1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22 /*
23 * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
24 * Copyright (c) 2017, Joyent, Inc.
25 * Copyright (c) 2012, 2014 by Delphix. All rights reserved.
26 */
27
28 /*
29 * DTrace - Dynamic Tracing for Solaris
30 *
31 * This is the implementation of the Solaris Dynamic Tracing framework
32 * (DTrace). The user-visible interface to DTrace is described at length in
33 * the "Solaris Dynamic Tracing Guide". The interfaces between the libdtrace
34 * library, the in-kernel DTrace framework, and the DTrace providers are
35 * described in the block comments in the <sys/dtrace.h> header file. The
36 * internal architecture of DTrace is described in the block comments in the
37 * <sys/dtrace_impl.h> header file. The comments contained within the DTrace
38 * implementation very much assume mastery of all of these sources; if one has
39 * an unanswered question about the implementation, one should consult them
40 * first.
41 *
42 * The functions here are ordered roughly as follows:
43 *
44 * - Probe context functions
45 * - Probe hashing functions
46 * - Non-probe context utility functions
47 * - Matching functions
48 * - Provider-to-Framework API functions
49 * - Probe management functions
50 * - DIF object functions
51 * - Format functions
52 * - Predicate functions
53 * - ECB functions
54 * - Buffer functions
55 * - Enabling functions
56 * - DOF functions
57 * - Anonymous enabling functions
58 * - Consumer state functions
59 * - Helper functions
60 * - Hook functions
61 * - Driver cookbook functions
62 *
63 * Each group of functions begins with a block comment labelled the "DTrace
64 * [Group] Functions", allowing one to find each block by searching forward
65 * on capital-f functions.
66 */
67 #include <sys/errno.h>
68 #include <sys/stat.h>
69 #include <sys/modctl.h>
70 #include <sys/conf.h>
71 #include <sys/systm.h>
72 #include <sys/ddi.h>
73 #include <sys/sunddi.h>
74 #include <sys/cpuvar.h>
75 #include <sys/kmem.h>
76 #include <sys/strsubr.h>
77 #include <sys/sysmacros.h>
78 #include <sys/dtrace_impl.h>
79 #include <sys/atomic.h>
80 #include <sys/cmn_err.h>
81 #include <sys/mutex_impl.h>
82 #include <sys/rwlock_impl.h>
83 #include <sys/ctf_api.h>
84 #include <sys/panic.h>
85 #include <sys/priv_impl.h>
86 #include <sys/policy.h>
87 #include <sys/cred_impl.h>
88 #include <sys/procfs_isa.h>
89 #include <sys/taskq.h>
90 #include <sys/mkdev.h>
91 #include <sys/kdi.h>
92 #include <sys/zone.h>
93 #include <sys/socket.h>
94 #include <netinet/in.h>
95 #include "strtolctype.h"
96
97 /*
98 * DTrace Tunable Variables
99 *
100 * The following variables may be tuned by adding a line to /etc/system that
101 * includes both the name of the DTrace module ("dtrace") and the name of the
102 * variable. For example:
103 *
104 * set dtrace:dtrace_destructive_disallow = 1
105 *
106 * In general, the only variables that one should be tuning this way are those
107 * that affect system-wide DTrace behavior, and for which the default behavior
108 * is undesirable. Most of these variables are tunable on a per-consumer
109 * basis using DTrace options, and need not be tuned on a system-wide basis.
110 * When tuning these variables, avoid pathological values; while some attempt
111 * is made to verify the integrity of these variables, they are not considered
112 * part of the supported interface to DTrace, and they are therefore not
113 * checked comprehensively. Further, these variables should not be tuned
114 * dynamically via "mdb -kw" or other means; they should only be tuned via
115 * /etc/system.
116 */
117 int dtrace_destructive_disallow = 0;
118 dtrace_optval_t dtrace_nonroot_maxsize = (16 * 1024 * 1024);
119 size_t dtrace_difo_maxsize = (256 * 1024);
120 dtrace_optval_t dtrace_dof_maxsize = (8 * 1024 * 1024);
121 size_t dtrace_statvar_maxsize = (16 * 1024);
122 size_t dtrace_actions_max = (16 * 1024);
123 size_t dtrace_retain_max = 1024;
124 dtrace_optval_t dtrace_helper_actions_max = 1024;
125 dtrace_optval_t dtrace_helper_providers_max = 32;
126 dtrace_optval_t dtrace_dstate_defsize = (1 * 1024 * 1024);
127 size_t dtrace_strsize_default = 256;
128 dtrace_optval_t dtrace_cleanrate_default = 9900990; /* 101 hz */
129 dtrace_optval_t dtrace_cleanrate_min = 200000; /* 5000 hz */
130 dtrace_optval_t dtrace_cleanrate_max = (uint64_t)60 * NANOSEC; /* 1/minute */
131 dtrace_optval_t dtrace_aggrate_default = NANOSEC; /* 1 hz */
132 dtrace_optval_t dtrace_statusrate_default = NANOSEC; /* 1 hz */
133 dtrace_optval_t dtrace_statusrate_max = (hrtime_t)10 * NANOSEC; /* 6/minute */
134 dtrace_optval_t dtrace_switchrate_default = NANOSEC; /* 1 hz */
135 dtrace_optval_t dtrace_nspec_default = 1;
136 dtrace_optval_t dtrace_specsize_default = 32 * 1024;
137 dtrace_optval_t dtrace_stackframes_default = 20;
138 dtrace_optval_t dtrace_ustackframes_default = 20;
139 dtrace_optval_t dtrace_jstackframes_default = 50;
140 dtrace_optval_t dtrace_jstackstrsize_default = 512;
141 int dtrace_msgdsize_max = 128;
142 hrtime_t dtrace_chill_max = MSEC2NSEC(500); /* 500 ms */
143 hrtime_t dtrace_chill_interval = NANOSEC; /* 1000 ms */
144 int dtrace_devdepth_max = 32;
145 int dtrace_err_verbose;
146 hrtime_t dtrace_deadman_interval = NANOSEC;
147 hrtime_t dtrace_deadman_timeout = (hrtime_t)10 * NANOSEC;
148 hrtime_t dtrace_deadman_user = (hrtime_t)30 * NANOSEC;
149 hrtime_t dtrace_unregister_defunct_reap = (hrtime_t)60 * NANOSEC;
150
151 /*
152 * DTrace External Variables
153 *
154 * As dtrace(7D) is a kernel module, any DTrace variables are obviously
155 * available to DTrace consumers via the backtick (`) syntax. One of these,
156 * dtrace_zero, is made deliberately so: it is provided as a source of
157 * well-known, zero-filled memory. While this variable is not documented,
158 * it is used by some translators as an implementation detail.
159 */
160 const char dtrace_zero[256] = { 0 }; /* zero-filled memory */
161
162 /*
163 * DTrace Internal Variables
164 */
165 static dev_info_t *dtrace_devi; /* device info */
166 static vmem_t *dtrace_arena; /* probe ID arena */
167 static vmem_t *dtrace_minor; /* minor number arena */
168 static taskq_t *dtrace_taskq; /* task queue */
169 static dtrace_probe_t **dtrace_probes; /* array of all probes */
170 static int dtrace_nprobes; /* number of probes */
171 static dtrace_provider_t *dtrace_provider; /* provider list */
172 static dtrace_meta_t *dtrace_meta_pid; /* user-land meta provider */
173 static int dtrace_opens; /* number of opens */
174 static int dtrace_helpers; /* number of helpers */
175 static int dtrace_getf; /* number of unpriv getf()s */
176 static void *dtrace_softstate; /* softstate pointer */
177 static dtrace_hash_t *dtrace_bymod; /* probes hashed by module */
178 static dtrace_hash_t *dtrace_byfunc; /* probes hashed by function */
179 static dtrace_hash_t *dtrace_byname; /* probes hashed by name */
180 static dtrace_toxrange_t *dtrace_toxrange; /* toxic range array */
181 static int dtrace_toxranges; /* number of toxic ranges */
182 static int dtrace_toxranges_max; /* size of toxic range array */
183 static dtrace_anon_t dtrace_anon; /* anonymous enabling */
184 static kmem_cache_t *dtrace_state_cache; /* cache for dynamic state */
185 static uint64_t dtrace_vtime_references; /* number of vtimestamp refs */
186 static kthread_t *dtrace_panicked; /* panicking thread */
187 static dtrace_ecb_t *dtrace_ecb_create_cache; /* cached created ECB */
188 static dtrace_genid_t dtrace_probegen; /* current probe generation */
189 static dtrace_helpers_t *dtrace_deferred_pid; /* deferred helper list */
190 static dtrace_enabling_t *dtrace_retained; /* list of retained enablings */
191 static dtrace_genid_t dtrace_retained_gen; /* current retained enab gen */
192 static dtrace_dynvar_t dtrace_dynhash_sink; /* end of dynamic hash chains */
193 static int dtrace_dynvar_failclean; /* dynvars failed to clean */
194
195 /*
196 * DTrace Locking
197 * DTrace is protected by three (relatively coarse-grained) locks:
198 *
199 * (1) dtrace_lock is required to manipulate essentially any DTrace state,
200 * including enabling state, probes, ECBs, consumer state, helper state,
201 * etc. Importantly, dtrace_lock is _not_ required when in probe context;
202 * probe context is lock-free -- synchronization is handled via the
203 * dtrace_sync() cross call mechanism.
204 *
205 * (2) dtrace_provider_lock is required when manipulating provider state, or
206 * when provider state must be held constant.
207 *
208 * (3) dtrace_meta_lock is required when manipulating meta provider state, or
209 * when meta provider state must be held constant.
210 *
211 * The lock ordering between these three locks is dtrace_meta_lock before
212 * dtrace_provider_lock before dtrace_lock. (In particular, there are
213 * several places where dtrace_provider_lock is held by the framework as it
214 * calls into the providers -- which then call back into the framework,
215 * grabbing dtrace_lock.)
216 *
217 * There are two other locks in the mix: mod_lock and cpu_lock. With respect
218 * to dtrace_provider_lock and dtrace_lock, cpu_lock continues its historical
219 * role as a coarse-grained lock; it is acquired before both of these locks.
220 * With respect to dtrace_meta_lock, its behavior is stranger: cpu_lock must
221 * be acquired _between_ dtrace_meta_lock and any other DTrace locks.
222 * mod_lock is similar with respect to dtrace_provider_lock in that it must be
223 * acquired _between_ dtrace_provider_lock and dtrace_lock.
224 */
225 static kmutex_t dtrace_lock; /* probe state lock */
226 static kmutex_t dtrace_provider_lock; /* provider state lock */
227 static kmutex_t dtrace_meta_lock; /* meta-provider state lock */
228
229 /*
230 * DTrace Provider Variables
231 *
232 * These are the variables relating to DTrace as a provider (that is, the
233 * provider of the BEGIN, END, and ERROR probes).
234 */
235 static dtrace_pattr_t dtrace_provider_attr = {
236 { DTRACE_STABILITY_STABLE, DTRACE_STABILITY_STABLE, DTRACE_CLASS_COMMON },
237 { DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN },
238 { DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN },
239 { DTRACE_STABILITY_STABLE, DTRACE_STABILITY_STABLE, DTRACE_CLASS_COMMON },
240 { DTRACE_STABILITY_STABLE, DTRACE_STABILITY_STABLE, DTRACE_CLASS_COMMON },
241 };
242
243 static void
244 dtrace_nullop(void)
245 {}
246
247 static int
248 dtrace_enable_nullop(void)
249 {
250 return (0);
251 }
252
253 static dtrace_pops_t dtrace_provider_ops = {
254 (void (*)(void *, const dtrace_probedesc_t *))dtrace_nullop,
255 (void (*)(void *, struct modctl *))dtrace_nullop,
256 (int (*)(void *, dtrace_id_t, void *))dtrace_enable_nullop,
257 (void (*)(void *, dtrace_id_t, void *))dtrace_nullop,
258 (void (*)(void *, dtrace_id_t, void *))dtrace_nullop,
259 (void (*)(void *, dtrace_id_t, void *))dtrace_nullop,
260 NULL,
261 NULL,
262 NULL,
263 (void (*)(void *, dtrace_id_t, void *))dtrace_nullop
264 };
265
266 static dtrace_id_t dtrace_probeid_begin; /* special BEGIN probe */
267 static dtrace_id_t dtrace_probeid_end; /* special END probe */
268 dtrace_id_t dtrace_probeid_error; /* special ERROR probe */
269
270 /*
271 * DTrace Helper Tracing Variables
272 *
273 * These variables should be set dynamically to enable helper tracing. The
274 * only variables that should be set are dtrace_helptrace_enable (which should
275 * be set to a non-zero value to allocate helper tracing buffers on the next
276 * open of /dev/dtrace) and dtrace_helptrace_disable (which should be set to a
277 * non-zero value to deallocate helper tracing buffers on the next close of
278 * /dev/dtrace). When (and only when) helper tracing is disabled, the
279 * buffer size may also be set via dtrace_helptrace_bufsize.
280 */
281 int dtrace_helptrace_enable = 0;
282 int dtrace_helptrace_disable = 0;
283 int dtrace_helptrace_bufsize = 16 * 1024 * 1024;
284 uint32_t dtrace_helptrace_nlocals;
285 static dtrace_helptrace_t *dtrace_helptrace_buffer;
286 static uint32_t dtrace_helptrace_next = 0;
287 static int dtrace_helptrace_wrapped = 0;
288
289 /*
290 * DTrace Error Hashing
291 *
292 * On DEBUG kernels, DTrace will track the errors that has seen in a hash
293 * table. This is very useful for checking coverage of tests that are
294 * expected to induce DIF or DOF processing errors, and may be useful for
295 * debugging problems in the DIF code generator or in DOF generation . The
296 * error hash may be examined with the ::dtrace_errhash MDB dcmd.
297 */
298 #ifdef DEBUG
299 static dtrace_errhash_t dtrace_errhash[DTRACE_ERRHASHSZ];
300 static const char *dtrace_errlast;
301 static kthread_t *dtrace_errthread;
302 static kmutex_t dtrace_errlock;
303 #endif
304
305 /*
306 * DTrace Macros and Constants
307 *
308 * These are various macros that are useful in various spots in the
309 * implementation, along with a few random constants that have no meaning
310 * outside of the implementation. There is no real structure to this cpp
311 * mishmash -- but is there ever?
312 */
313 #define DTRACE_HASHSTR(hash, probe) \
314 dtrace_hash_str(*((char **)((uintptr_t)(probe) + (hash)->dth_stroffs)))
315
316 #define DTRACE_HASHNEXT(hash, probe) \
317 (dtrace_probe_t **)((uintptr_t)(probe) + (hash)->dth_nextoffs)
318
319 #define DTRACE_HASHPREV(hash, probe) \
320 (dtrace_probe_t **)((uintptr_t)(probe) + (hash)->dth_prevoffs)
321
322 #define DTRACE_HASHEQ(hash, lhs, rhs) \
323 (strcmp(*((char **)((uintptr_t)(lhs) + (hash)->dth_stroffs)), \
324 *((char **)((uintptr_t)(rhs) + (hash)->dth_stroffs))) == 0)
325
326 #define DTRACE_AGGHASHSIZE_SLEW 17
327
328 #define DTRACE_V4MAPPED_OFFSET (sizeof (uint32_t) * 3)
329
330 /*
331 * The key for a thread-local variable consists of the lower 61 bits of the
332 * t_did, plus the 3 bits of the highest active interrupt above LOCK_LEVEL.
333 * We add DIF_VARIABLE_MAX to t_did to assure that the thread key is never
334 * equal to a variable identifier. This is necessary (but not sufficient) to
335 * assure that global associative arrays never collide with thread-local
336 * variables. To guarantee that they cannot collide, we must also define the
337 * order for keying dynamic variables. That order is:
338 *
339 * [ key0 ] ... [ keyn ] [ variable-key ] [ tls-key ]
340 *
341 * Because the variable-key and the tls-key are in orthogonal spaces, there is
342 * no way for a global variable key signature to match a thread-local key
343 * signature.
344 */
345 #define DTRACE_TLS_THRKEY(where) { \
346 uint_t intr = 0; \
347 uint_t actv = CPU->cpu_intr_actv >> (LOCK_LEVEL + 1); \
348 for (; actv; actv >>= 1) \
349 intr++; \
350 ASSERT(intr < (1 << 3)); \
351 (where) = ((curthread->t_did + DIF_VARIABLE_MAX) & \
352 (((uint64_t)1 << 61) - 1)) | ((uint64_t)intr << 61); \
353 }
354
355 #define DT_BSWAP_8(x) ((x) & 0xff)
356 #define DT_BSWAP_16(x) ((DT_BSWAP_8(x) << 8) | DT_BSWAP_8((x) >> 8))
357 #define DT_BSWAP_32(x) ((DT_BSWAP_16(x) << 16) | DT_BSWAP_16((x) >> 16))
358 #define DT_BSWAP_64(x) ((DT_BSWAP_32(x) << 32) | DT_BSWAP_32((x) >> 32))
359
360 #define DT_MASK_LO 0x00000000FFFFFFFFULL
361
362 #define DTRACE_STORE(type, tomax, offset, what) \
363 *((type *)((uintptr_t)(tomax) + (uintptr_t)offset)) = (type)(what);
364
365 #ifndef __x86
366 #define DTRACE_ALIGNCHECK(addr, size, flags) \
367 if (addr & (size - 1)) { \
368 *flags |= CPU_DTRACE_BADALIGN; \
369 cpu_core[CPU->cpu_id].cpuc_dtrace_illval = addr; \
370 return (0); \
371 }
372 #else
373 #define DTRACE_ALIGNCHECK(addr, size, flags)
374 #endif
375
376 /*
377 * Test whether a range of memory starting at testaddr of size testsz falls
378 * within the range of memory described by addr, sz. We take care to avoid
379 * problems with overflow and underflow of the unsigned quantities, and
380 * disallow all negative sizes. Ranges of size 0 are allowed.
381 */
382 #define DTRACE_INRANGE(testaddr, testsz, baseaddr, basesz) \
383 ((testaddr) - (uintptr_t)(baseaddr) < (basesz) && \
384 (testaddr) + (testsz) - (uintptr_t)(baseaddr) <= (basesz) && \
385 (testaddr) + (testsz) >= (testaddr))
386
387 #define DTRACE_RANGE_REMAIN(remp, addr, baseaddr, basesz) \
388 do { \
389 if ((remp) != NULL) { \
390 *(remp) = (uintptr_t)(baseaddr) + (basesz) - (addr); \
391 } \
392 _NOTE(CONSTCOND) } while (0)
393
394
395 /*
396 * Test whether alloc_sz bytes will fit in the scratch region. We isolate
397 * alloc_sz on the righthand side of the comparison in order to avoid overflow
398 * or underflow in the comparison with it. This is simpler than the INRANGE
399 * check above, because we know that the dtms_scratch_ptr is valid in the
400 * range. Allocations of size zero are allowed.
401 */
402 #define DTRACE_INSCRATCH(mstate, alloc_sz) \
403 ((mstate)->dtms_scratch_base + (mstate)->dtms_scratch_size - \
404 (mstate)->dtms_scratch_ptr >= (alloc_sz))
405
406 #define DTRACE_LOADFUNC(bits) \
407 /*CSTYLED*/ \
408 uint##bits##_t \
409 dtrace_load##bits(uintptr_t addr) \
410 { \
411 size_t size = bits / NBBY; \
412 /*CSTYLED*/ \
413 uint##bits##_t rval; \
414 int i; \
415 volatile uint16_t *flags = (volatile uint16_t *) \
416 &cpu_core[CPU->cpu_id].cpuc_dtrace_flags; \
417 \
418 DTRACE_ALIGNCHECK(addr, size, flags); \
419 \
420 for (i = 0; i < dtrace_toxranges; i++) { \
421 if (addr >= dtrace_toxrange[i].dtt_limit) \
422 continue; \
423 \
424 if (addr + size <= dtrace_toxrange[i].dtt_base) \
425 continue; \
426 \
427 /* \
428 * This address falls within a toxic region; return 0. \
429 */ \
430 *flags |= CPU_DTRACE_BADADDR; \
431 cpu_core[CPU->cpu_id].cpuc_dtrace_illval = addr; \
432 return (0); \
433 } \
434 \
435 *flags |= CPU_DTRACE_NOFAULT; \
436 /*CSTYLED*/ \
437 rval = *((volatile uint##bits##_t *)addr); \
438 *flags &= ~CPU_DTRACE_NOFAULT; \
439 \
440 return (!(*flags & CPU_DTRACE_FAULT) ? rval : 0); \
441 }
442
443 #ifdef _LP64
444 #define dtrace_loadptr dtrace_load64
445 #else
446 #define dtrace_loadptr dtrace_load32
447 #endif
448
449 #define DTRACE_DYNHASH_FREE 0
450 #define DTRACE_DYNHASH_SINK 1
451 #define DTRACE_DYNHASH_VALID 2
452
453 #define DTRACE_MATCH_FAIL -1
454 #define DTRACE_MATCH_NEXT 0
455 #define DTRACE_MATCH_DONE 1
456 #define DTRACE_ANCHORED(probe) ((probe)->dtpr_func[0] != '\0')
457 #define DTRACE_STATE_ALIGN 64
458
459 #define DTRACE_FLAGS2FLT(flags) \
460 (((flags) & CPU_DTRACE_BADADDR) ? DTRACEFLT_BADADDR : \
461 ((flags) & CPU_DTRACE_ILLOP) ? DTRACEFLT_ILLOP : \
462 ((flags) & CPU_DTRACE_DIVZERO) ? DTRACEFLT_DIVZERO : \
463 ((flags) & CPU_DTRACE_KPRIV) ? DTRACEFLT_KPRIV : \
464 ((flags) & CPU_DTRACE_UPRIV) ? DTRACEFLT_UPRIV : \
465 ((flags) & CPU_DTRACE_TUPOFLOW) ? DTRACEFLT_TUPOFLOW : \
466 ((flags) & CPU_DTRACE_BADALIGN) ? DTRACEFLT_BADALIGN : \
467 ((flags) & CPU_DTRACE_NOSCRATCH) ? DTRACEFLT_NOSCRATCH : \
468 ((flags) & CPU_DTRACE_BADSTACK) ? DTRACEFLT_BADSTACK : \
469 DTRACEFLT_UNKNOWN)
470
471 #define DTRACEACT_ISSTRING(act) \
472 ((act)->dta_kind == DTRACEACT_DIFEXPR && \
473 (act)->dta_difo->dtdo_rtype.dtdt_kind == DIF_TYPE_STRING)
474
475 static size_t dtrace_strlen(const char *, size_t);
476 static dtrace_probe_t *dtrace_probe_lookup_id(dtrace_id_t id);
477 static void dtrace_enabling_provide(dtrace_provider_t *);
478 static int dtrace_enabling_match(dtrace_enabling_t *, int *);
479 static void dtrace_enabling_matchall(void);
480 static void dtrace_enabling_reap(void);
481 static dtrace_state_t *dtrace_anon_grab(void);
482 static uint64_t dtrace_helper(int, dtrace_mstate_t *,
483 dtrace_state_t *, uint64_t, uint64_t);
484 static dtrace_helpers_t *dtrace_helpers_create(proc_t *);
485 static void dtrace_buffer_drop(dtrace_buffer_t *);
486 static int dtrace_buffer_consumed(dtrace_buffer_t *, hrtime_t when);
487 static intptr_t dtrace_buffer_reserve(dtrace_buffer_t *, size_t, size_t,
488 dtrace_state_t *, dtrace_mstate_t *);
489 static int dtrace_state_option(dtrace_state_t *, dtrace_optid_t,
490 dtrace_optval_t);
491 static int dtrace_ecb_create_enable(dtrace_probe_t *, void *);
492 static void dtrace_helper_provider_destroy(dtrace_helper_provider_t *);
493 static int dtrace_priv_proc(dtrace_state_t *, dtrace_mstate_t *);
494 static void dtrace_getf_barrier(void);
495 static int dtrace_canload_remains(uint64_t, size_t, size_t *,
496 dtrace_mstate_t *, dtrace_vstate_t *);
497 static int dtrace_canstore_remains(uint64_t, size_t, size_t *,
498 dtrace_mstate_t *, dtrace_vstate_t *);
499
500 /*
501 * DTrace Probe Context Functions
502 *
503 * These functions are called from probe context. Because probe context is
504 * any context in which C may be called, arbitrarily locks may be held,
505 * interrupts may be disabled, we may be in arbitrary dispatched state, etc.
506 * As a result, functions called from probe context may only call other DTrace
507 * support functions -- they may not interact at all with the system at large.
508 * (Note that the ASSERT macro is made probe-context safe by redefining it in
509 * terms of dtrace_assfail(), a probe-context safe function.) If arbitrary
510 * loads are to be performed from probe context, they _must_ be in terms of
511 * the safe dtrace_load*() variants.
512 *
513 * Some functions in this block are not actually called from probe context;
514 * for these functions, there will be a comment above the function reading
515 * "Note: not called from probe context."
516 */
517 void
518 dtrace_panic(const char *format, ...)
519 {
520 va_list alist;
521
522 va_start(alist, format);
523 dtrace_vpanic(format, alist);
524 va_end(alist);
525 }
526
527 int
528 dtrace_assfail(const char *a, const char *f, int l)
529 {
530 dtrace_panic("assertion failed: %s, file: %s, line: %d", a, f, l);
531
532 /*
533 * We just need something here that even the most clever compiler
534 * cannot optimize away.
535 */
536 return (a[(uintptr_t)f]);
537 }
538
539 /*
540 * Atomically increment a specified error counter from probe context.
541 */
542 static void
543 dtrace_error(uint32_t *counter)
544 {
545 /*
546 * Most counters stored to in probe context are per-CPU counters.
547 * However, there are some error conditions that are sufficiently
548 * arcane that they don't merit per-CPU storage. If these counters
549 * are incremented concurrently on different CPUs, scalability will be
550 * adversely affected -- but we don't expect them to be white-hot in a
551 * correctly constructed enabling...
552 */
553 uint32_t oval, nval;
554
555 do {
556 oval = *counter;
557
558 if ((nval = oval + 1) == 0) {
559 /*
560 * If the counter would wrap, set it to 1 -- assuring
561 * that the counter is never zero when we have seen
562 * errors. (The counter must be 32-bits because we
563 * aren't guaranteed a 64-bit compare&swap operation.)
564 * To save this code both the infamy of being fingered
565 * by a priggish news story and the indignity of being
566 * the target of a neo-puritan witch trial, we're
567 * carefully avoiding any colorful description of the
568 * likelihood of this condition -- but suffice it to
569 * say that it is only slightly more likely than the
570 * overflow of predicate cache IDs, as discussed in
571 * dtrace_predicate_create().
572 */
573 nval = 1;
574 }
575 } while (dtrace_cas32(counter, oval, nval) != oval);
576 }
577
578 /*
579 * Use the DTRACE_LOADFUNC macro to define functions for each of loading a
580 * uint8_t, a uint16_t, a uint32_t and a uint64_t.
581 */
582 /* BEGIN CSTYLED */
583 DTRACE_LOADFUNC(8)
584 DTRACE_LOADFUNC(16)
585 DTRACE_LOADFUNC(32)
586 DTRACE_LOADFUNC(64)
587 /* END CSTYLED */
588
589 static int
590 dtrace_inscratch(uintptr_t dest, size_t size, dtrace_mstate_t *mstate)
591 {
592 if (dest < mstate->dtms_scratch_base)
593 return (0);
594
595 if (dest + size < dest)
596 return (0);
597
598 if (dest + size > mstate->dtms_scratch_ptr)
599 return (0);
600
601 return (1);
602 }
603
604 static int
605 dtrace_canstore_statvar(uint64_t addr, size_t sz, size_t *remain,
606 dtrace_statvar_t **svars, int nsvars)
607 {
608 int i;
609 size_t maxglobalsize, maxlocalsize;
610
611 if (nsvars == 0)
612 return (0);
613
614 maxglobalsize = dtrace_statvar_maxsize + sizeof (uint64_t);
615 maxlocalsize = maxglobalsize * NCPU;
616
617 for (i = 0; i < nsvars; i++) {
618 dtrace_statvar_t *svar = svars[i];
619 uint8_t scope;
620 size_t size;
621
622 if (svar == NULL || (size = svar->dtsv_size) == 0)
623 continue;
624
625 scope = svar->dtsv_var.dtdv_scope;
626
627 /*
628 * We verify that our size is valid in the spirit of providing
629 * defense in depth: we want to prevent attackers from using
630 * DTrace to escalate an orthogonal kernel heap corruption bug
631 * into the ability to store to arbitrary locations in memory.
632 */
633 VERIFY((scope == DIFV_SCOPE_GLOBAL && size <= maxglobalsize) ||
634 (scope == DIFV_SCOPE_LOCAL && size <= maxlocalsize));
635
636 if (DTRACE_INRANGE(addr, sz, svar->dtsv_data,
637 svar->dtsv_size)) {
638 DTRACE_RANGE_REMAIN(remain, addr, svar->dtsv_data,
639 svar->dtsv_size);
640 return (1);
641 }
642 }
643
644 return (0);
645 }
646
647 /*
648 * Check to see if the address is within a memory region to which a store may
649 * be issued. This includes the DTrace scratch areas, and any DTrace variable
650 * region. The caller of dtrace_canstore() is responsible for performing any
651 * alignment checks that are needed before stores are actually executed.
652 */
653 static int
654 dtrace_canstore(uint64_t addr, size_t sz, dtrace_mstate_t *mstate,
655 dtrace_vstate_t *vstate)
656 {
657 return (dtrace_canstore_remains(addr, sz, NULL, mstate, vstate));
658 }
659
660 /*
661 * Implementation of dtrace_canstore which communicates the upper bound of the
662 * allowed memory region.
663 */
664 static int
665 dtrace_canstore_remains(uint64_t addr, size_t sz, size_t *remain,
666 dtrace_mstate_t *mstate, dtrace_vstate_t *vstate)
667 {
668 /*
669 * First, check to see if the address is in scratch space...
670 */
671 if (DTRACE_INRANGE(addr, sz, mstate->dtms_scratch_base,
672 mstate->dtms_scratch_size)) {
673 DTRACE_RANGE_REMAIN(remain, addr, mstate->dtms_scratch_base,
674 mstate->dtms_scratch_size);
675 return (1);
676 }
677
678 /*
679 * Now check to see if it's a dynamic variable. This check will pick
680 * up both thread-local variables and any global dynamically-allocated
681 * variables.
682 */
683 if (DTRACE_INRANGE(addr, sz, vstate->dtvs_dynvars.dtds_base,
684 vstate->dtvs_dynvars.dtds_size)) {
685 dtrace_dstate_t *dstate = &vstate->dtvs_dynvars;
686 uintptr_t base = (uintptr_t)dstate->dtds_base +
687 (dstate->dtds_hashsize * sizeof (dtrace_dynhash_t));
688 uintptr_t chunkoffs;
689 dtrace_dynvar_t *dvar;
690
691 /*
692 * Before we assume that we can store here, we need to make
693 * sure that it isn't in our metadata -- storing to our
694 * dynamic variable metadata would corrupt our state. For
695 * the range to not include any dynamic variable metadata,
696 * it must:
697 *
698 * (1) Start above the hash table that is at the base of
699 * the dynamic variable space
700 *
701 * (2) Have a starting chunk offset that is beyond the
702 * dtrace_dynvar_t that is at the base of every chunk
703 *
704 * (3) Not span a chunk boundary
705 *
706 * (4) Not be in the tuple space of a dynamic variable
707 *
708 */
709 if (addr < base)
710 return (0);
711
712 chunkoffs = (addr - base) % dstate->dtds_chunksize;
713
714 if (chunkoffs < sizeof (dtrace_dynvar_t))
715 return (0);
716
717 if (chunkoffs + sz > dstate->dtds_chunksize)
718 return (0);
719
720 dvar = (dtrace_dynvar_t *)((uintptr_t)addr - chunkoffs);
721
722 if (dvar->dtdv_hashval == DTRACE_DYNHASH_FREE)
723 return (0);
724
725 if (chunkoffs < sizeof (dtrace_dynvar_t) +
726 ((dvar->dtdv_tuple.dtt_nkeys - 1) * sizeof (dtrace_key_t)))
727 return (0);
728
729 DTRACE_RANGE_REMAIN(remain, addr, dvar, dstate->dtds_chunksize);
730 return (1);
731 }
732
733 /*
734 * Finally, check the static local and global variables. These checks
735 * take the longest, so we perform them last.
736 */
737 if (dtrace_canstore_statvar(addr, sz, remain,
738 vstate->dtvs_locals, vstate->dtvs_nlocals))
739 return (1);
740
741 if (dtrace_canstore_statvar(addr, sz, remain,
742 vstate->dtvs_globals, vstate->dtvs_nglobals))
743 return (1);
744
745 return (0);
746 }
747
748
749 /*
750 * Convenience routine to check to see if the address is within a memory
751 * region in which a load may be issued given the user's privilege level;
752 * if not, it sets the appropriate error flags and loads 'addr' into the
753 * illegal value slot.
754 *
755 * DTrace subroutines (DIF_SUBR_*) should use this helper to implement
756 * appropriate memory access protection.
757 */
758 static int
759 dtrace_canload(uint64_t addr, size_t sz, dtrace_mstate_t *mstate,
760 dtrace_vstate_t *vstate)
761 {
762 return (dtrace_canload_remains(addr, sz, NULL, mstate, vstate));
763 }
764
765 /*
766 * Implementation of dtrace_canload which communicates the upper bound of the
767 * allowed memory region.
768 */
769 static int
770 dtrace_canload_remains(uint64_t addr, size_t sz, size_t *remain,
771 dtrace_mstate_t *mstate, dtrace_vstate_t *vstate)
772 {
773 volatile uintptr_t *illval = &cpu_core[CPU->cpu_id].cpuc_dtrace_illval;
774 file_t *fp;
775
776 /*
777 * If we hold the privilege to read from kernel memory, then
778 * everything is readable.
779 */
780 if ((mstate->dtms_access & DTRACE_ACCESS_KERNEL) != 0) {
781 DTRACE_RANGE_REMAIN(remain, addr, addr, sz);
782 return (1);
783 }
784
785 /*
786 * You can obviously read that which you can store.
787 */
788 if (dtrace_canstore_remains(addr, sz, remain, mstate, vstate))
789 return (1);
790
791 /*
792 * We're allowed to read from our own string table.
793 */
794 if (DTRACE_INRANGE(addr, sz, mstate->dtms_difo->dtdo_strtab,
795 mstate->dtms_difo->dtdo_strlen)) {
796 DTRACE_RANGE_REMAIN(remain, addr,
797 mstate->dtms_difo->dtdo_strtab,
798 mstate->dtms_difo->dtdo_strlen);
799 return (1);
800 }
801
802 if (vstate->dtvs_state != NULL &&
803 dtrace_priv_proc(vstate->dtvs_state, mstate)) {
804 proc_t *p;
805
806 /*
807 * When we have privileges to the current process, there are
808 * several context-related kernel structures that are safe to
809 * read, even absent the privilege to read from kernel memory.
810 * These reads are safe because these structures contain only
811 * state that (1) we're permitted to read, (2) is harmless or
812 * (3) contains pointers to additional kernel state that we're
813 * not permitted to read (and as such, do not present an
814 * opportunity for privilege escalation). Finally (and
815 * critically), because of the nature of their relation with
816 * the current thread context, the memory associated with these
817 * structures cannot change over the duration of probe context,
818 * and it is therefore impossible for this memory to be
819 * deallocated and reallocated as something else while it's
820 * being operated upon.
821 */
822 if (DTRACE_INRANGE(addr, sz, curthread, sizeof (kthread_t))) {
823 DTRACE_RANGE_REMAIN(remain, addr, curthread,
824 sizeof (kthread_t));
825 return (1);
826 }
827
828 if ((p = curthread->t_procp) != NULL && DTRACE_INRANGE(addr,
829 sz, curthread->t_procp, sizeof (proc_t))) {
830 DTRACE_RANGE_REMAIN(remain, addr, curthread->t_procp,
831 sizeof (proc_t));
832 return (1);
833 }
834
835 if (curthread->t_cred != NULL && DTRACE_INRANGE(addr, sz,
836 curthread->t_cred, sizeof (cred_t))) {
837 DTRACE_RANGE_REMAIN(remain, addr, curthread->t_cred,
838 sizeof (cred_t));
839 return (1);
840 }
841
842 if (p != NULL && p->p_pidp != NULL && DTRACE_INRANGE(addr, sz,
843 &(p->p_pidp->pid_id), sizeof (pid_t))) {
844 DTRACE_RANGE_REMAIN(remain, addr, &(p->p_pidp->pid_id),
845 sizeof (pid_t));
846 return (1);
847 }
848
849 if (curthread->t_cpu != NULL && DTRACE_INRANGE(addr, sz,
850 curthread->t_cpu, offsetof(cpu_t, cpu_pause_thread))) {
851 DTRACE_RANGE_REMAIN(remain, addr, curthread->t_cpu,
852 offsetof(cpu_t, cpu_pause_thread));
853 return (1);
854 }
855 }
856
857 if ((fp = mstate->dtms_getf) != NULL) {
858 uintptr_t psz = sizeof (void *);
859 vnode_t *vp;
860 vnodeops_t *op;
861
862 /*
863 * When getf() returns a file_t, the enabling is implicitly
864 * granted the (transient) right to read the returned file_t
865 * as well as the v_path and v_op->vnop_name of the underlying
866 * vnode. These accesses are allowed after a successful
867 * getf() because the members that they refer to cannot change
868 * once set -- and the barrier logic in the kernel's closef()
869 * path assures that the file_t and its referenced vode_t
870 * cannot themselves be stale (that is, it impossible for
871 * either dtms_getf itself or its f_vnode member to reference
872 * freed memory).
873 */
874 if (DTRACE_INRANGE(addr, sz, fp, sizeof (file_t))) {
875 DTRACE_RANGE_REMAIN(remain, addr, fp, sizeof (file_t));
876 return (1);
877 }
878
879 if ((vp = fp->f_vnode) != NULL) {
880 size_t slen;
881
882 if (DTRACE_INRANGE(addr, sz, &vp->v_path, psz)) {
883 DTRACE_RANGE_REMAIN(remain, addr, &vp->v_path,
884 psz);
885 return (1);
886 }
887
888 slen = strlen(vp->v_path) + 1;
889 if (DTRACE_INRANGE(addr, sz, vp->v_path, slen)) {
890 DTRACE_RANGE_REMAIN(remain, addr, vp->v_path,
891 slen);
892 return (1);
893 }
894
895 if (DTRACE_INRANGE(addr, sz, &vp->v_op, psz)) {
896 DTRACE_RANGE_REMAIN(remain, addr, &vp->v_op,
897 psz);
898 return (1);
899 }
900
901 if ((op = vp->v_op) != NULL &&
902 DTRACE_INRANGE(addr, sz, &op->vnop_name, psz)) {
903 DTRACE_RANGE_REMAIN(remain, addr,
904 &op->vnop_name, psz);
905 return (1);
906 }
907
908 if (op != NULL && op->vnop_name != NULL &&
909 DTRACE_INRANGE(addr, sz, op->vnop_name,
910 (slen = strlen(op->vnop_name) + 1))) {
911 DTRACE_RANGE_REMAIN(remain, addr,
912 op->vnop_name, slen);
913 return (1);
914 }
915 }
916 }
917
918 DTRACE_CPUFLAG_SET(CPU_DTRACE_KPRIV);
919 *illval = addr;
920 return (0);
921 }
922
923 /*
924 * Convenience routine to check to see if a given string is within a memory
925 * region in which a load may be issued given the user's privilege level;
926 * this exists so that we don't need to issue unnecessary dtrace_strlen()
927 * calls in the event that the user has all privileges.
928 */
929 static int
930 dtrace_strcanload(uint64_t addr, size_t sz, size_t *remain,
931 dtrace_mstate_t *mstate, dtrace_vstate_t *vstate)
932 {
933 size_t rsize;
934
935 /*
936 * If we hold the privilege to read from kernel memory, then
937 * everything is readable.
938 */
939 if ((mstate->dtms_access & DTRACE_ACCESS_KERNEL) != 0) {
940 DTRACE_RANGE_REMAIN(remain, addr, addr, sz);
941 return (1);
942 }
943
944 /*
945 * Even if the caller is uninterested in querying the remaining valid
946 * range, it is required to ensure that the access is allowed.
947 */
948 if (remain == NULL) {
949 remain = &rsize;
950 }
951 if (dtrace_canload_remains(addr, 0, remain, mstate, vstate)) {
952 size_t strsz;
953 /*
954 * Perform the strlen after determining the length of the
955 * memory region which is accessible. This prevents timing
956 * information from being used to find NULs in memory which is
957 * not accessible to the caller.
958 */
959 strsz = 1 + dtrace_strlen((char *)(uintptr_t)addr,
960 MIN(sz, *remain));
961 if (strsz <= *remain) {
962 return (1);
963 }
964 }
965
966 return (0);
967 }
968
969 /*
970 * Convenience routine to check to see if a given variable is within a memory
971 * region in which a load may be issued given the user's privilege level.
972 */
973 static int
974 dtrace_vcanload(void *src, dtrace_diftype_t *type, size_t *remain,
975 dtrace_mstate_t *mstate, dtrace_vstate_t *vstate)
976 {
977 size_t sz;
978 ASSERT(type->dtdt_flags & DIF_TF_BYREF);
979
980 /*
981 * Calculate the max size before performing any checks since even
982 * DTRACE_ACCESS_KERNEL-credentialed callers expect that this function
983 * return the max length via 'remain'.
984 */
985 if (type->dtdt_kind == DIF_TYPE_STRING) {
986 dtrace_state_t *state = vstate->dtvs_state;
987
988 if (state != NULL) {
989 sz = state->dts_options[DTRACEOPT_STRSIZE];
990 } else {
991 /*
992 * In helper context, we have a NULL state; fall back
993 * to using the system-wide default for the string size
994 * in this case.
995 */
996 sz = dtrace_strsize_default;
997 }
998 } else {
999 sz = type->dtdt_size;
1000 }
1001
1002 /*
1003 * If we hold the privilege to read from kernel memory, then
1004 * everything is readable.
1005 */
1006 if ((mstate->dtms_access & DTRACE_ACCESS_KERNEL) != 0) {
1007 DTRACE_RANGE_REMAIN(remain, (uintptr_t)src, src, sz);
1008 return (1);
1009 }
1010
1011 if (type->dtdt_kind == DIF_TYPE_STRING) {
1012 return (dtrace_strcanload((uintptr_t)src, sz, remain, mstate,
1013 vstate));
1014 }
1015 return (dtrace_canload_remains((uintptr_t)src, sz, remain, mstate,
1016 vstate));
1017 }
1018
1019 /*
1020 * Convert a string to a signed integer using safe loads.
1021 *
1022 * NOTE: This function uses various macros from strtolctype.h to manipulate
1023 * digit values, etc -- these have all been checked to ensure they make
1024 * no additional function calls.
1025 */
1026 static int64_t
1027 dtrace_strtoll(char *input, int base, size_t limit)
1028 {
1029 uintptr_t pos = (uintptr_t)input;
1030 int64_t val = 0;
1031 int x;
1032 boolean_t neg = B_FALSE;
1033 char c, cc, ccc;
1034 uintptr_t end = pos + limit;
1035
1036 /*
1037 * Consume any whitespace preceding digits.
1038 */
1039 while ((c = dtrace_load8(pos)) == ' ' || c == '\t')
1040 pos++;
1041
1042 /*
1043 * Handle an explicit sign if one is present.
1044 */
1045 if (c == '-' || c == '+') {
1046 if (c == '-')
1047 neg = B_TRUE;
1048 c = dtrace_load8(++pos);
1049 }
1050
1051 /*
1052 * Check for an explicit hexadecimal prefix ("0x" or "0X") and skip it
1053 * if present.
1054 */
1055 if (base == 16 && c == '0' && ((cc = dtrace_load8(pos + 1)) == 'x' ||
1056 cc == 'X') && isxdigit(ccc = dtrace_load8(pos + 2))) {
1057 pos += 2;
1058 c = ccc;
1059 }
1060
1061 /*
1062 * Read in contiguous digits until the first non-digit character.
1063 */
1064 for (; pos < end && c != '\0' && lisalnum(c) && (x = DIGIT(c)) < base;
1065 c = dtrace_load8(++pos))
1066 val = val * base + x;
1067
1068 return (neg ? -val : val);
1069 }
1070
1071 /*
1072 * Compare two strings using safe loads.
1073 */
1074 static int
1075 dtrace_strncmp(char *s1, char *s2, size_t limit)
1076 {
1077 uint8_t c1, c2;
1078 volatile uint16_t *flags;
1079
1080 if (s1 == s2 || limit == 0)
1081 return (0);
1082
1083 flags = (volatile uint16_t *)&cpu_core[CPU->cpu_id].cpuc_dtrace_flags;
1084
1085 do {
1086 if (s1 == NULL) {
1087 c1 = '\0';
1088 } else {
1089 c1 = dtrace_load8((uintptr_t)s1++);
1090 }
1091
1092 if (s2 == NULL) {
1093 c2 = '\0';
1094 } else {
1095 c2 = dtrace_load8((uintptr_t)s2++);
1096 }
1097
1098 if (c1 != c2)
1099 return (c1 - c2);
1100 } while (--limit && c1 != '\0' && !(*flags & CPU_DTRACE_FAULT));
1101
1102 return (0);
1103 }
1104
1105 /*
1106 * Compute strlen(s) for a string using safe memory accesses. The additional
1107 * len parameter is used to specify a maximum length to ensure completion.
1108 */
1109 static size_t
1110 dtrace_strlen(const char *s, size_t lim)
1111 {
1112 uint_t len;
1113
1114 for (len = 0; len != lim; len++) {
1115 if (dtrace_load8((uintptr_t)s++) == '\0')
1116 break;
1117 }
1118
1119 return (len);
1120 }
1121
1122 /*
1123 * Check if an address falls within a toxic region.
1124 */
1125 static int
1126 dtrace_istoxic(uintptr_t kaddr, size_t size)
1127 {
1128 uintptr_t taddr, tsize;
1129 int i;
1130
1131 for (i = 0; i < dtrace_toxranges; i++) {
1132 taddr = dtrace_toxrange[i].dtt_base;
1133 tsize = dtrace_toxrange[i].dtt_limit - taddr;
1134
1135 if (kaddr - taddr < tsize) {
1136 DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR);
1137 cpu_core[CPU->cpu_id].cpuc_dtrace_illval = kaddr;
1138 return (1);
1139 }
1140
1141 if (taddr - kaddr < size) {
1142 DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR);
1143 cpu_core[CPU->cpu_id].cpuc_dtrace_illval = taddr;
1144 return (1);
1145 }
1146 }
1147
1148 return (0);
1149 }
1150
1151 /*
1152 * Copy src to dst using safe memory accesses. The src is assumed to be unsafe
1153 * memory specified by the DIF program. The dst is assumed to be safe memory
1154 * that we can store to directly because it is managed by DTrace. As with
1155 * standard bcopy, overlapping copies are handled properly.
1156 */
1157 static void
1158 dtrace_bcopy(const void *src, void *dst, size_t len)
1159 {
1160 if (len != 0) {
1161 uint8_t *s1 = dst;
1162 const uint8_t *s2 = src;
1163
1164 if (s1 <= s2) {
1165 do {
1166 *s1++ = dtrace_load8((uintptr_t)s2++);
1167 } while (--len != 0);
1168 } else {
1169 s2 += len;
1170 s1 += len;
1171
1172 do {
1173 *--s1 = dtrace_load8((uintptr_t)--s2);
1174 } while (--len != 0);
1175 }
1176 }
1177 }
1178
1179 /*
1180 * Copy src to dst using safe memory accesses, up to either the specified
1181 * length, or the point that a nul byte is encountered. The src is assumed to
1182 * be unsafe memory specified by the DIF program. The dst is assumed to be
1183 * safe memory that we can store to directly because it is managed by DTrace.
1184 * Unlike dtrace_bcopy(), overlapping regions are not handled.
1185 */
1186 static void
1187 dtrace_strcpy(const void *src, void *dst, size_t len)
1188 {
1189 if (len != 0) {
1190 uint8_t *s1 = dst, c;
1191 const uint8_t *s2 = src;
1192
1193 do {
1194 *s1++ = c = dtrace_load8((uintptr_t)s2++);
1195 } while (--len != 0 && c != '\0');
1196 }
1197 }
1198
1199 /*
1200 * Copy src to dst, deriving the size and type from the specified (BYREF)
1201 * variable type. The src is assumed to be unsafe memory specified by the DIF
1202 * program. The dst is assumed to be DTrace variable memory that is of the
1203 * specified type; we assume that we can store to directly.
1204 */
1205 static void
1206 dtrace_vcopy(void *src, void *dst, dtrace_diftype_t *type, size_t limit)
1207 {
1208 ASSERT(type->dtdt_flags & DIF_TF_BYREF);
1209
1210 if (type->dtdt_kind == DIF_TYPE_STRING) {
1211 dtrace_strcpy(src, dst, MIN(type->dtdt_size, limit));
1212 } else {
1213 dtrace_bcopy(src, dst, MIN(type->dtdt_size, limit));
1214 }
1215 }
1216
1217 /*
1218 * Compare s1 to s2 using safe memory accesses. The s1 data is assumed to be
1219 * unsafe memory specified by the DIF program. The s2 data is assumed to be
1220 * safe memory that we can access directly because it is managed by DTrace.
1221 */
1222 static int
1223 dtrace_bcmp(const void *s1, const void *s2, size_t len)
1224 {
1225 volatile uint16_t *flags;
1226
1227 flags = (volatile uint16_t *)&cpu_core[CPU->cpu_id].cpuc_dtrace_flags;
1228
1229 if (s1 == s2)
1230 return (0);
1231
1232 if (s1 == NULL || s2 == NULL)
1233 return (1);
1234
1235 if (s1 != s2 && len != 0) {
1236 const uint8_t *ps1 = s1;
1237 const uint8_t *ps2 = s2;
1238
1239 do {
1240 if (dtrace_load8((uintptr_t)ps1++) != *ps2++)
1241 return (1);
1242 } while (--len != 0 && !(*flags & CPU_DTRACE_FAULT));
1243 }
1244 return (0);
1245 }
1246
1247 /*
1248 * Zero the specified region using a simple byte-by-byte loop. Note that this
1249 * is for safe DTrace-managed memory only.
1250 */
1251 static void
1252 dtrace_bzero(void *dst, size_t len)
1253 {
1254 uchar_t *cp;
1255
1256 for (cp = dst; len != 0; len--)
1257 *cp++ = 0;
1258 }
1259
1260 static void
1261 dtrace_add_128(uint64_t *addend1, uint64_t *addend2, uint64_t *sum)
1262 {
1263 uint64_t result[2];
1264
1265 result[0] = addend1[0] + addend2[0];
1266 result[1] = addend1[1] + addend2[1] +
1267 (result[0] < addend1[0] || result[0] < addend2[0] ? 1 : 0);
1268
1269 sum[0] = result[0];
1270 sum[1] = result[1];
1271 }
1272
1273 /*
1274 * Shift the 128-bit value in a by b. If b is positive, shift left.
1275 * If b is negative, shift right.
1276 */
1277 static void
1278 dtrace_shift_128(uint64_t *a, int b)
1279 {
1280 uint64_t mask;
1281
1282 if (b == 0)
1283 return;
1284
1285 if (b < 0) {
1286 b = -b;
1287 if (b >= 64) {
1288 a[0] = a[1] >> (b - 64);
1289 a[1] = 0;
1290 } else {
1291 a[0] >>= b;
1292 mask = 1LL << (64 - b);
1293 mask -= 1;
1294 a[0] |= ((a[1] & mask) << (64 - b));
1295 a[1] >>= b;
1296 }
1297 } else {
1298 if (b >= 64) {
1299 a[1] = a[0] << (b - 64);
1300 a[0] = 0;
1301 } else {
1302 a[1] <<= b;
1303 mask = a[0] >> (64 - b);
1304 a[1] |= mask;
1305 a[0] <<= b;
1306 }
1307 }
1308 }
1309
1310 /*
1311 * The basic idea is to break the 2 64-bit values into 4 32-bit values,
1312 * use native multiplication on those, and then re-combine into the
1313 * resulting 128-bit value.
1314 *
1315 * (hi1 << 32 + lo1) * (hi2 << 32 + lo2) =
1316 * hi1 * hi2 << 64 +
1317 * hi1 * lo2 << 32 +
1318 * hi2 * lo1 << 32 +
1319 * lo1 * lo2
1320 */
1321 static void
1322 dtrace_multiply_128(uint64_t factor1, uint64_t factor2, uint64_t *product)
1323 {
1324 uint64_t hi1, hi2, lo1, lo2;
1325 uint64_t tmp[2];
1326
1327 hi1 = factor1 >> 32;
1328 hi2 = factor2 >> 32;
1329
1330 lo1 = factor1 & DT_MASK_LO;
1331 lo2 = factor2 & DT_MASK_LO;
1332
1333 product[0] = lo1 * lo2;
1334 product[1] = hi1 * hi2;
1335
1336 tmp[0] = hi1 * lo2;
1337 tmp[1] = 0;
1338 dtrace_shift_128(tmp, 32);
1339 dtrace_add_128(product, tmp, product);
1340
1341 tmp[0] = hi2 * lo1;
1342 tmp[1] = 0;
1343 dtrace_shift_128(tmp, 32);
1344 dtrace_add_128(product, tmp, product);
1345 }
1346
1347 /*
1348 * This privilege check should be used by actions and subroutines to
1349 * verify that the user credentials of the process that enabled the
1350 * invoking ECB match the target credentials
1351 */
1352 static int
1353 dtrace_priv_proc_common_user(dtrace_state_t *state)
1354 {
1355 cred_t *cr, *s_cr = state->dts_cred.dcr_cred;
1356
1357 /*
1358 * We should always have a non-NULL state cred here, since if cred
1359 * is null (anonymous tracing), we fast-path bypass this routine.
1360 */
1361 ASSERT(s_cr != NULL);
1362
1363 if ((cr = CRED()) != NULL &&
1364 s_cr->cr_uid == cr->cr_uid &&
1365 s_cr->cr_uid == cr->cr_ruid &&
1366 s_cr->cr_uid == cr->cr_suid &&
1367 s_cr->cr_gid == cr->cr_gid &&
1368 s_cr->cr_gid == cr->cr_rgid &&
1369 s_cr->cr_gid == cr->cr_sgid)
1370 return (1);
1371
1372 return (0);
1373 }
1374
1375 /*
1376 * This privilege check should be used by actions and subroutines to
1377 * verify that the zone of the process that enabled the invoking ECB
1378 * matches the target credentials
1379 */
1380 static int
1381 dtrace_priv_proc_common_zone(dtrace_state_t *state)
1382 {
1383 cred_t *cr, *s_cr = state->dts_cred.dcr_cred;
1384
1385 /*
1386 * We should always have a non-NULL state cred here, since if cred
1387 * is null (anonymous tracing), we fast-path bypass this routine.
1388 */
1389 ASSERT(s_cr != NULL);
1390
1391 if ((cr = CRED()) != NULL && s_cr->cr_zone == cr->cr_zone)
1392 return (1);
1393
1394 return (0);
1395 }
1396
1397 /*
1398 * This privilege check should be used by actions and subroutines to
1399 * verify that the process has not setuid or changed credentials.
1400 */
1401 static int
1402 dtrace_priv_proc_common_nocd()
1403 {
1404 proc_t *proc;
1405
1406 if ((proc = ttoproc(curthread)) != NULL &&
1407 !(proc->p_flag & SNOCD))
1408 return (1);
1409
1410 return (0);
1411 }
1412
1413 static int
1414 dtrace_priv_proc_destructive(dtrace_state_t *state, dtrace_mstate_t *mstate)
1415 {
1416 int action = state->dts_cred.dcr_action;
1417
1418 if (!(mstate->dtms_access & DTRACE_ACCESS_PROC))
1419 goto bad;
1420
1421 if (((action & DTRACE_CRA_PROC_DESTRUCTIVE_ALLZONE) == 0) &&
1422 dtrace_priv_proc_common_zone(state) == 0)
1423 goto bad;
1424
1425 if (((action & DTRACE_CRA_PROC_DESTRUCTIVE_ALLUSER) == 0) &&
1426 dtrace_priv_proc_common_user(state) == 0)
1427 goto bad;
1428
1429 if (((action & DTRACE_CRA_PROC_DESTRUCTIVE_CREDCHG) == 0) &&
1430 dtrace_priv_proc_common_nocd() == 0)
1431 goto bad;
1432
1433 return (1);
1434
1435 bad:
1436 cpu_core[CPU->cpu_id].cpuc_dtrace_flags |= CPU_DTRACE_UPRIV;
1437
1438 return (0);
1439 }
1440
1441 static int
1442 dtrace_priv_proc_control(dtrace_state_t *state, dtrace_mstate_t *mstate)
1443 {
1444 if (mstate->dtms_access & DTRACE_ACCESS_PROC) {
1445 if (state->dts_cred.dcr_action & DTRACE_CRA_PROC_CONTROL)
1446 return (1);
1447
1448 if (dtrace_priv_proc_common_zone(state) &&
1449 dtrace_priv_proc_common_user(state) &&
1450 dtrace_priv_proc_common_nocd())
1451 return (1);
1452 }
1453
1454 cpu_core[CPU->cpu_id].cpuc_dtrace_flags |= CPU_DTRACE_UPRIV;
1455
1456 return (0);
1457 }
1458
1459 static int
1460 dtrace_priv_proc(dtrace_state_t *state, dtrace_mstate_t *mstate)
1461 {
1462 if ((mstate->dtms_access & DTRACE_ACCESS_PROC) &&
1463 (state->dts_cred.dcr_action & DTRACE_CRA_PROC))
1464 return (1);
1465
1466 cpu_core[CPU->cpu_id].cpuc_dtrace_flags |= CPU_DTRACE_UPRIV;
1467
1468 return (0);
1469 }
1470
1471 static int
1472 dtrace_priv_kernel(dtrace_state_t *state)
1473 {
1474 if (state->dts_cred.dcr_action & DTRACE_CRA_KERNEL)
1475 return (1);
1476
1477 cpu_core[CPU->cpu_id].cpuc_dtrace_flags |= CPU_DTRACE_KPRIV;
1478
1479 return (0);
1480 }
1481
1482 static int
1483 dtrace_priv_kernel_destructive(dtrace_state_t *state)
1484 {
1485 if (state->dts_cred.dcr_action & DTRACE_CRA_KERNEL_DESTRUCTIVE)
1486 return (1);
1487
1488 cpu_core[CPU->cpu_id].cpuc_dtrace_flags |= CPU_DTRACE_KPRIV;
1489
1490 return (0);
1491 }
1492
1493 /*
1494 * Determine if the dte_cond of the specified ECB allows for processing of
1495 * the current probe to continue. Note that this routine may allow continued
1496 * processing, but with access(es) stripped from the mstate's dtms_access
1497 * field.
1498 */
1499 static int
1500 dtrace_priv_probe(dtrace_state_t *state, dtrace_mstate_t *mstate,
1501 dtrace_ecb_t *ecb)
1502 {
1503 dtrace_probe_t *probe = ecb->dte_probe;
1504 dtrace_provider_t *prov = probe->dtpr_provider;
1505 dtrace_pops_t *pops = &prov->dtpv_pops;
1506 int mode = DTRACE_MODE_NOPRIV_DROP;
1507
1508 ASSERT(ecb->dte_cond);
1509
1510 if (pops->dtps_mode != NULL) {
1511 mode = pops->dtps_mode(prov->dtpv_arg,
1512 probe->dtpr_id, probe->dtpr_arg);
1513
1514 ASSERT(mode & (DTRACE_MODE_USER | DTRACE_MODE_KERNEL));
1515 ASSERT(mode & (DTRACE_MODE_NOPRIV_RESTRICT |
1516 DTRACE_MODE_NOPRIV_DROP));
1517 }
1518
1519 /*
1520 * If the dte_cond bits indicate that this consumer is only allowed to
1521 * see user-mode firings of this probe, check that the probe was fired
1522 * while in a user context. If that's not the case, use the policy
1523 * specified by the provider to determine if we drop the probe or
1524 * merely restrict operation.
1525 */
1526 if (ecb->dte_cond & DTRACE_COND_USERMODE) {
1527 ASSERT(mode != DTRACE_MODE_NOPRIV_DROP);
1528
1529 if (!(mode & DTRACE_MODE_USER)) {
1530 if (mode & DTRACE_MODE_NOPRIV_DROP)
1531 return (0);
1532
1533 mstate->dtms_access &= ~DTRACE_ACCESS_ARGS;
1534 }
1535 }
1536
1537 /*
1538 * This is more subtle than it looks. We have to be absolutely certain
1539 * that CRED() isn't going to change out from under us so it's only
1540 * legit to examine that structure if we're in constrained situations.
1541 * Currently, the only times we'll this check is if a non-super-user
1542 * has enabled the profile or syscall providers -- providers that
1543 * allow visibility of all processes. For the profile case, the check
1544 * above will ensure that we're examining a user context.
1545 */
1546 if (ecb->dte_cond & DTRACE_COND_OWNER) {
1547 cred_t *cr;
1548 cred_t *s_cr = state->dts_cred.dcr_cred;
1549 proc_t *proc;
1550
1551 ASSERT(s_cr != NULL);
1552
1553 if ((cr = CRED()) == NULL ||
1554 s_cr->cr_uid != cr->cr_uid ||
1555 s_cr->cr_uid != cr->cr_ruid ||
1556 s_cr->cr_uid != cr->cr_suid ||
1557 s_cr->cr_gid != cr->cr_gid ||
1558 s_cr->cr_gid != cr->cr_rgid ||
1559 s_cr->cr_gid != cr->cr_sgid ||
1560 (proc = ttoproc(curthread)) == NULL ||
1561 (proc->p_flag & SNOCD)) {
1562 if (mode & DTRACE_MODE_NOPRIV_DROP)
1563 return (0);
1564
1565 mstate->dtms_access &= ~DTRACE_ACCESS_PROC;
1566 }
1567 }
1568
1569 /*
1570 * If our dte_cond is set to DTRACE_COND_ZONEOWNER and we are not
1571 * in our zone, check to see if our mode policy is to restrict rather
1572 * than to drop; if to restrict, strip away both DTRACE_ACCESS_PROC
1573 * and DTRACE_ACCESS_ARGS
1574 */
1575 if (ecb->dte_cond & DTRACE_COND_ZONEOWNER) {
1576 cred_t *cr;
1577 cred_t *s_cr = state->dts_cred.dcr_cred;
1578
1579 ASSERT(s_cr != NULL);
1580
1581 if ((cr = CRED()) == NULL ||
1582 s_cr->cr_zone->zone_id != cr->cr_zone->zone_id) {
1583 if (mode & DTRACE_MODE_NOPRIV_DROP)
1584 return (0);
1585
1586 mstate->dtms_access &=
1587 ~(DTRACE_ACCESS_PROC | DTRACE_ACCESS_ARGS);
1588 }
1589 }
1590
1591 /*
1592 * By merits of being in this code path at all, we have limited
1593 * privileges. If the provider has indicated that limited privileges
1594 * are to denote restricted operation, strip off the ability to access
1595 * arguments.
1596 */
1597 if (mode & DTRACE_MODE_LIMITEDPRIV_RESTRICT)
1598 mstate->dtms_access &= ~DTRACE_ACCESS_ARGS;
1599
1600 return (1);
1601 }
1602
1603 /*
1604 * Note: not called from probe context. This function is called
1605 * asynchronously (and at a regular interval) from outside of probe context to
1606 * clean the dirty dynamic variable lists on all CPUs. Dynamic variable
1607 * cleaning is explained in detail in <sys/dtrace_impl.h>.
1608 */
1609 void
1610 dtrace_dynvar_clean(dtrace_dstate_t *dstate)
1611 {
1612 dtrace_dynvar_t *dirty;
1613 dtrace_dstate_percpu_t *dcpu;
1614 dtrace_dynvar_t **rinsep;
1615 int i, j, work = 0;
1616
1617 for (i = 0; i < NCPU; i++) {
1618 dcpu = &dstate->dtds_percpu[i];
1619 rinsep = &dcpu->dtdsc_rinsing;
1620
1621 /*
1622 * If the dirty list is NULL, there is no dirty work to do.
1623 */
1624 if (dcpu->dtdsc_dirty == NULL)
1625 continue;
1626
1627 if (dcpu->dtdsc_rinsing != NULL) {
1628 /*
1629 * If the rinsing list is non-NULL, then it is because
1630 * this CPU was selected to accept another CPU's
1631 * dirty list -- and since that time, dirty buffers
1632 * have accumulated. This is a highly unlikely
1633 * condition, but we choose to ignore the dirty
1634 * buffers -- they'll be picked up a future cleanse.
1635 */
1636 continue;
1637 }
1638
1639 if (dcpu->dtdsc_clean != NULL) {
1640 /*
1641 * If the clean list is non-NULL, then we're in a
1642 * situation where a CPU has done deallocations (we
1643 * have a non-NULL dirty list) but no allocations (we
1644 * also have a non-NULL clean list). We can't simply
1645 * move the dirty list into the clean list on this
1646 * CPU, yet we also don't want to allow this condition
1647 * to persist, lest a short clean list prevent a
1648 * massive dirty list from being cleaned (which in
1649 * turn could lead to otherwise avoidable dynamic
1650 * drops). To deal with this, we look for some CPU
1651 * with a NULL clean list, NULL dirty list, and NULL
1652 * rinsing list -- and then we borrow this CPU to
1653 * rinse our dirty list.
1654 */
1655 for (j = 0; j < NCPU; j++) {
1656 dtrace_dstate_percpu_t *rinser;
1657
1658 rinser = &dstate->dtds_percpu[j];
1659
1660 if (rinser->dtdsc_rinsing != NULL)
1661 continue;
1662
1663 if (rinser->dtdsc_dirty != NULL)
1664 continue;
1665
1666 if (rinser->dtdsc_clean != NULL)
1667 continue;
1668
1669 rinsep = &rinser->dtdsc_rinsing;
1670 break;
1671 }
1672
1673 if (j == NCPU) {
1674 /*
1675 * We were unable to find another CPU that
1676 * could accept this dirty list -- we are
1677 * therefore unable to clean it now.
1678 */
1679 dtrace_dynvar_failclean++;
1680 continue;
1681 }
1682 }
1683
1684 work = 1;
1685
1686 /*
1687 * Atomically move the dirty list aside.
1688 */
1689 do {
1690 dirty = dcpu->dtdsc_dirty;
1691
1692 /*
1693 * Before we zap the dirty list, set the rinsing list.
1694 * (This allows for a potential assertion in
1695 * dtrace_dynvar(): if a free dynamic variable appears
1696 * on a hash chain, either the dirty list or the
1697 * rinsing list for some CPU must be non-NULL.)
1698 */
1699 *rinsep = dirty;
1700 dtrace_membar_producer();
1701 } while (dtrace_casptr(&dcpu->dtdsc_dirty,
1702 dirty, NULL) != dirty);
1703 }
1704
1705 if (!work) {
1706 /*
1707 * We have no work to do; we can simply return.
1708 */
1709 return;
1710 }
1711
1712 dtrace_sync();
1713
1714 for (i = 0; i < NCPU; i++) {
1715 dcpu = &dstate->dtds_percpu[i];
1716
1717 if (dcpu->dtdsc_rinsing == NULL)
1718 continue;
1719
1720 /*
1721 * We are now guaranteed that no hash chain contains a pointer
1722 * into this dirty list; we can make it clean.
1723 */
1724 ASSERT(dcpu->dtdsc_clean == NULL);
1725 dcpu->dtdsc_clean = dcpu->dtdsc_rinsing;
1726 dcpu->dtdsc_rinsing = NULL;
1727 }
1728
1729 /*
1730 * Before we actually set the state to be DTRACE_DSTATE_CLEAN, make
1731 * sure that all CPUs have seen all of the dtdsc_clean pointers.
1732 * This prevents a race whereby a CPU incorrectly decides that
1733 * the state should be something other than DTRACE_DSTATE_CLEAN
1734 * after dtrace_dynvar_clean() has completed.
1735 */
1736 dtrace_sync();
1737
1738 dstate->dtds_state = DTRACE_DSTATE_CLEAN;
1739 }
1740
1741 /*
1742 * Depending on the value of the op parameter, this function looks-up,
1743 * allocates or deallocates an arbitrarily-keyed dynamic variable. If an
1744 * allocation is requested, this function will return a pointer to a
1745 * dtrace_dynvar_t corresponding to the allocated variable -- or NULL if no
1746 * variable can be allocated. If NULL is returned, the appropriate counter
1747 * will be incremented.
1748 */
1749 dtrace_dynvar_t *
1750 dtrace_dynvar(dtrace_dstate_t *dstate, uint_t nkeys,
1751 dtrace_key_t *key, size_t dsize, dtrace_dynvar_op_t op,
1752 dtrace_mstate_t *mstate, dtrace_vstate_t *vstate)
1753 {
1754 uint64_t hashval = DTRACE_DYNHASH_VALID;
1755 dtrace_dynhash_t *hash = dstate->dtds_hash;
1756 dtrace_dynvar_t *free, *new_free, *next, *dvar, *start, *prev = NULL;
1757 processorid_t me = CPU->cpu_id, cpu = me;
1758 dtrace_dstate_percpu_t *dcpu = &dstate->dtds_percpu[me];
1759 size_t bucket, ksize;
1760 size_t chunksize = dstate->dtds_chunksize;
1761 uintptr_t kdata, lock, nstate;
1762 uint_t i;
1763
1764 ASSERT(nkeys != 0);
1765
1766 /*
1767 * Hash the key. As with aggregations, we use Jenkins' "One-at-a-time"
1768 * algorithm. For the by-value portions, we perform the algorithm in
1769 * 16-bit chunks (as opposed to 8-bit chunks). This speeds things up a
1770 * bit, and seems to have only a minute effect on distribution. For
1771 * the by-reference data, we perform "One-at-a-time" iterating (safely)
1772 * over each referenced byte. It's painful to do this, but it's much
1773 * better than pathological hash distribution. The efficacy of the
1774 * hashing algorithm (and a comparison with other algorithms) may be
1775 * found by running the ::dtrace_dynstat MDB dcmd.
1776 */
1777 for (i = 0; i < nkeys; i++) {
1778 if (key[i].dttk_size == 0) {
1779 uint64_t val = key[i].dttk_value;
1780
1781 hashval += (val >> 48) & 0xffff;
1782 hashval += (hashval << 10);
1783 hashval ^= (hashval >> 6);
1784
1785 hashval += (val >> 32) & 0xffff;
1786 hashval += (hashval << 10);
1787 hashval ^= (hashval >> 6);
1788
1789 hashval += (val >> 16) & 0xffff;
1790 hashval += (hashval << 10);
1791 hashval ^= (hashval >> 6);
1792
1793 hashval += val & 0xffff;
1794 hashval += (hashval << 10);
1795 hashval ^= (hashval >> 6);
1796 } else {
1797 /*
1798 * This is incredibly painful, but it beats the hell
1799 * out of the alternative.
1800 */
1801 uint64_t j, size = key[i].dttk_size;
1802 uintptr_t base = (uintptr_t)key[i].dttk_value;
1803
1804 if (!dtrace_canload(base, size, mstate, vstate))
1805 break;
1806
1807 for (j = 0; j < size; j++) {
1808 hashval += dtrace_load8(base + j);
1809 hashval += (hashval << 10);
1810 hashval ^= (hashval >> 6);
1811 }
1812 }
1813 }
1814
1815 if (DTRACE_CPUFLAG_ISSET(CPU_DTRACE_FAULT))
1816 return (NULL);
1817
1818 hashval += (hashval << 3);
1819 hashval ^= (hashval >> 11);
1820 hashval += (hashval << 15);
1821
1822 /*
1823 * There is a remote chance (ideally, 1 in 2^31) that our hashval
1824 * comes out to be one of our two sentinel hash values. If this
1825 * actually happens, we set the hashval to be a value known to be a
1826 * non-sentinel value.
1827 */
1828 if (hashval == DTRACE_DYNHASH_FREE || hashval == DTRACE_DYNHASH_SINK)
1829 hashval = DTRACE_DYNHASH_VALID;
1830
1831 /*
1832 * Yes, it's painful to do a divide here. If the cycle count becomes
1833 * important here, tricks can be pulled to reduce it. (However, it's
1834 * critical that hash collisions be kept to an absolute minimum;
1835 * they're much more painful than a divide.) It's better to have a
1836 * solution that generates few collisions and still keeps things
1837 * relatively simple.
1838 */
1839 bucket = hashval % dstate->dtds_hashsize;
1840
1841 if (op == DTRACE_DYNVAR_DEALLOC) {
1842 volatile uintptr_t *lockp = &hash[bucket].dtdh_lock;
1843
1844 for (;;) {
1845 while ((lock = *lockp) & 1)
1846 continue;
1847
1848 if (dtrace_casptr((void *)lockp,
1849 (void *)lock, (void *)(lock + 1)) == (void *)lock)
1850 break;
1851 }
1852
1853 dtrace_membar_producer();
1854 }
1855
1856 top:
1857 prev = NULL;
1858 lock = hash[bucket].dtdh_lock;
1859
1860 dtrace_membar_consumer();
1861
1862 start = hash[bucket].dtdh_chain;
1863 ASSERT(start != NULL && (start->dtdv_hashval == DTRACE_DYNHASH_SINK ||
1864 start->dtdv_hashval != DTRACE_DYNHASH_FREE ||
1865 op != DTRACE_DYNVAR_DEALLOC));
1866
1867 for (dvar = start; dvar != NULL; dvar = dvar->dtdv_next) {
1868 dtrace_tuple_t *dtuple = &dvar->dtdv_tuple;
1869 dtrace_key_t *dkey = &dtuple->dtt_key[0];
1870
1871 if (dvar->dtdv_hashval != hashval) {
1872 if (dvar->dtdv_hashval == DTRACE_DYNHASH_SINK) {
1873 /*
1874 * We've reached the sink, and therefore the
1875 * end of the hash chain; we can kick out of
1876 * the loop knowing that we have seen a valid
1877 * snapshot of state.
1878 */
1879 ASSERT(dvar->dtdv_next == NULL);
1880 ASSERT(dvar == &dtrace_dynhash_sink);
1881 break;
1882 }
1883
1884 if (dvar->dtdv_hashval == DTRACE_DYNHASH_FREE) {
1885 /*
1886 * We've gone off the rails: somewhere along
1887 * the line, one of the members of this hash
1888 * chain was deleted. Note that we could also
1889 * detect this by simply letting this loop run
1890 * to completion, as we would eventually hit
1891 * the end of the dirty list. However, we
1892 * want to avoid running the length of the
1893 * dirty list unnecessarily (it might be quite
1894 * long), so we catch this as early as
1895 * possible by detecting the hash marker. In
1896 * this case, we simply set dvar to NULL and
1897 * break; the conditional after the loop will
1898 * send us back to top.
1899 */
1900 dvar = NULL;
1901 break;
1902 }
1903
1904 goto next;
1905 }
1906
1907 if (dtuple->dtt_nkeys != nkeys)
1908 goto next;
1909
1910 for (i = 0; i < nkeys; i++, dkey++) {
1911 if (dkey->dttk_size != key[i].dttk_size)
1912 goto next; /* size or type mismatch */
1913
1914 if (dkey->dttk_size != 0) {
1915 if (dtrace_bcmp(
1916 (void *)(uintptr_t)key[i].dttk_value,
1917 (void *)(uintptr_t)dkey->dttk_value,
1918 dkey->dttk_size))
1919 goto next;
1920 } else {
1921 if (dkey->dttk_value != key[i].dttk_value)
1922 goto next;
1923 }
1924 }
1925
1926 if (op != DTRACE_DYNVAR_DEALLOC)
1927 return (dvar);
1928
1929 ASSERT(dvar->dtdv_next == NULL ||
1930 dvar->dtdv_next->dtdv_hashval != DTRACE_DYNHASH_FREE);
1931
1932 if (prev != NULL) {
1933 ASSERT(hash[bucket].dtdh_chain != dvar);
1934 ASSERT(start != dvar);
1935 ASSERT(prev->dtdv_next == dvar);
1936 prev->dtdv_next = dvar->dtdv_next;
1937 } else {
1938 if (dtrace_casptr(&hash[bucket].dtdh_chain,
1939 start, dvar->dtdv_next) != start) {
1940 /*
1941 * We have failed to atomically swing the
1942 * hash table head pointer, presumably because
1943 * of a conflicting allocation on another CPU.
1944 * We need to reread the hash chain and try
1945 * again.
1946 */
1947 goto top;
1948 }
1949 }
1950
1951 dtrace_membar_producer();
1952
1953 /*
1954 * Now set the hash value to indicate that it's free.
1955 */
1956 ASSERT(hash[bucket].dtdh_chain != dvar);
1957 dvar->dtdv_hashval = DTRACE_DYNHASH_FREE;
1958
1959 dtrace_membar_producer();
1960
1961 /*
1962 * Set the next pointer to point at the dirty list, and
1963 * atomically swing the dirty pointer to the newly freed dvar.
1964 */
1965 do {
1966 next = dcpu->dtdsc_dirty;
1967 dvar->dtdv_next = next;
1968 } while (dtrace_casptr(&dcpu->dtdsc_dirty, next, dvar) != next);
1969
1970 /*
1971 * Finally, unlock this hash bucket.
1972 */
1973 ASSERT(hash[bucket].dtdh_lock == lock);
1974 ASSERT(lock & 1);
1975 hash[bucket].dtdh_lock++;
1976
1977 return (NULL);
1978 next:
1979 prev = dvar;
1980 continue;
1981 }
1982
1983 if (dvar == NULL) {
1984 /*
1985 * If dvar is NULL, it is because we went off the rails:
1986 * one of the elements that we traversed in the hash chain
1987 * was deleted while we were traversing it. In this case,
1988 * we assert that we aren't doing a dealloc (deallocs lock
1989 * the hash bucket to prevent themselves from racing with
1990 * one another), and retry the hash chain traversal.
1991 */
1992 ASSERT(op != DTRACE_DYNVAR_DEALLOC);
1993 goto top;
1994 }
1995
1996 if (op != DTRACE_DYNVAR_ALLOC) {
1997 /*
1998 * If we are not to allocate a new variable, we want to
1999 * return NULL now. Before we return, check that the value
2000 * of the lock word hasn't changed. If it has, we may have
2001 * seen an inconsistent snapshot.
2002 */
2003 if (op == DTRACE_DYNVAR_NOALLOC) {
2004 if (hash[bucket].dtdh_lock != lock)
2005 goto top;
2006 } else {
2007 ASSERT(op == DTRACE_DYNVAR_DEALLOC);
2008 ASSERT(hash[bucket].dtdh_lock == lock);
2009 ASSERT(lock & 1);
2010 hash[bucket].dtdh_lock++;
2011 }
2012
2013 return (NULL);
2014 }
2015
2016 /*
2017 * We need to allocate a new dynamic variable. The size we need is the
2018 * size of dtrace_dynvar plus the size of nkeys dtrace_key_t's plus the
2019 * size of any auxiliary key data (rounded up to 8-byte alignment) plus
2020 * the size of any referred-to data (dsize). We then round the final
2021 * size up to the chunksize for allocation.
2022 */
2023 for (ksize = 0, i = 0; i < nkeys; i++)
2024 ksize += P2ROUNDUP(key[i].dttk_size, sizeof (uint64_t));
2025
2026 /*
2027 * This should be pretty much impossible, but could happen if, say,
2028 * strange DIF specified the tuple. Ideally, this should be an
2029 * assertion and not an error condition -- but that requires that the
2030 * chunksize calculation in dtrace_difo_chunksize() be absolutely
2031 * bullet-proof. (That is, it must not be able to be fooled by
2032 * malicious DIF.) Given the lack of backwards branches in DIF,
2033 * solving this would presumably not amount to solving the Halting
2034 * Problem -- but it still seems awfully hard.
2035 */
2036 if (sizeof (dtrace_dynvar_t) + sizeof (dtrace_key_t) * (nkeys - 1) +
2037 ksize + dsize > chunksize) {
2038 dcpu->dtdsc_drops++;
2039 return (NULL);
2040 }
2041
2042 nstate = DTRACE_DSTATE_EMPTY;
2043
2044 do {
2045 retry:
2046 free = dcpu->dtdsc_free;
2047
2048 if (free == NULL) {
2049 dtrace_dynvar_t *clean = dcpu->dtdsc_clean;
2050 void *rval;
2051
2052 if (clean == NULL) {
2053 /*
2054 * We're out of dynamic variable space on
2055 * this CPU. Unless we have tried all CPUs,
2056 * we'll try to allocate from a different
2057 * CPU.
2058 */
2059 switch (dstate->dtds_state) {
2060 case DTRACE_DSTATE_CLEAN: {
2061 void *sp = &dstate->dtds_state;
2062
2063 if (++cpu >= NCPU)
2064 cpu = 0;
2065
2066 if (dcpu->dtdsc_dirty != NULL &&
2067 nstate == DTRACE_DSTATE_EMPTY)
2068 nstate = DTRACE_DSTATE_DIRTY;
2069
2070 if (dcpu->dtdsc_rinsing != NULL)
2071 nstate = DTRACE_DSTATE_RINSING;
2072
2073 dcpu = &dstate->dtds_percpu[cpu];
2074
2075 if (cpu != me)
2076 goto retry;
2077
2078 (void) dtrace_cas32(sp,
2079 DTRACE_DSTATE_CLEAN, nstate);
2080
2081 /*
2082 * To increment the correct bean
2083 * counter, take another lap.
2084 */
2085 goto retry;
2086 }
2087
2088 case DTRACE_DSTATE_DIRTY:
2089 dcpu->dtdsc_dirty_drops++;
2090 break;
2091
2092 case DTRACE_DSTATE_RINSING:
2093 dcpu->dtdsc_rinsing_drops++;
2094 break;
2095
2096 case DTRACE_DSTATE_EMPTY:
2097 dcpu->dtdsc_drops++;
2098 break;
2099 }
2100
2101 DTRACE_CPUFLAG_SET(CPU_DTRACE_DROP);
2102 return (NULL);
2103 }
2104
2105 /*
2106 * The clean list appears to be non-empty. We want to
2107 * move the clean list to the free list; we start by
2108 * moving the clean pointer aside.
2109 */
2110 if (dtrace_casptr(&dcpu->dtdsc_clean,
2111 clean, NULL) != clean) {
2112 /*
2113 * We are in one of two situations:
2114 *
2115 * (a) The clean list was switched to the
2116 * free list by another CPU.
2117 *
2118 * (b) The clean list was added to by the
2119 * cleansing cyclic.
2120 *
2121 * In either of these situations, we can
2122 * just reattempt the free list allocation.
2123 */
2124 goto retry;
2125 }
2126
2127 ASSERT(clean->dtdv_hashval == DTRACE_DYNHASH_FREE);
2128
2129 /*
2130 * Now we'll move the clean list to our free list.
2131 * It's impossible for this to fail: the only way
2132 * the free list can be updated is through this
2133 * code path, and only one CPU can own the clean list.
2134 * Thus, it would only be possible for this to fail if
2135 * this code were racing with dtrace_dynvar_clean().
2136 * (That is, if dtrace_dynvar_clean() updated the clean
2137 * list, and we ended up racing to update the free
2138 * list.) This race is prevented by the dtrace_sync()
2139 * in dtrace_dynvar_clean() -- which flushes the
2140 * owners of the clean lists out before resetting
2141 * the clean lists.
2142 */
2143 dcpu = &dstate->dtds_percpu[me];
2144 rval = dtrace_casptr(&dcpu->dtdsc_free, NULL, clean);
2145 ASSERT(rval == NULL);
2146 goto retry;
2147 }
2148
2149 dvar = free;
2150 new_free = dvar->dtdv_next;
2151 } while (dtrace_casptr(&dcpu->dtdsc_free, free, new_free) != free);
2152
2153 /*
2154 * We have now allocated a new chunk. We copy the tuple keys into the
2155 * tuple array and copy any referenced key data into the data space
2156 * following the tuple array. As we do this, we relocate dttk_value
2157 * in the final tuple to point to the key data address in the chunk.
2158 */
2159 kdata = (uintptr_t)&dvar->dtdv_tuple.dtt_key[nkeys];
2160 dvar->dtdv_data = (void *)(kdata + ksize);
2161 dvar->dtdv_tuple.dtt_nkeys = nkeys;
2162
2163 for (i = 0; i < nkeys; i++) {
2164 dtrace_key_t *dkey = &dvar->dtdv_tuple.dtt_key[i];
2165 size_t kesize = key[i].dttk_size;
2166
2167 if (kesize != 0) {
2168 dtrace_bcopy(
2169 (const void *)(uintptr_t)key[i].dttk_value,
2170 (void *)kdata, kesize);
2171 dkey->dttk_value = kdata;
2172 kdata += P2ROUNDUP(kesize, sizeof (uint64_t));
2173 } else {
2174 dkey->dttk_value = key[i].dttk_value;
2175 }
2176
2177 dkey->dttk_size = kesize;
2178 }
2179
2180 ASSERT(dvar->dtdv_hashval == DTRACE_DYNHASH_FREE);
2181 dvar->dtdv_hashval = hashval;
2182 dvar->dtdv_next = start;
2183
2184 if (dtrace_casptr(&hash[bucket].dtdh_chain, start, dvar) == start)
2185 return (dvar);
2186
2187 /*
2188 * The cas has failed. Either another CPU is adding an element to
2189 * this hash chain, or another CPU is deleting an element from this
2190 * hash chain. The simplest way to deal with both of these cases
2191 * (though not necessarily the most efficient) is to free our
2192 * allocated block and re-attempt it all. Note that the free is
2193 * to the dirty list and _not_ to the free list. This is to prevent
2194 * races with allocators, above.
2195 */
2196 dvar->dtdv_hashval = DTRACE_DYNHASH_FREE;
2197
2198 dtrace_membar_producer();
2199
2200 do {
2201 free = dcpu->dtdsc_dirty;
2202 dvar->dtdv_next = free;
2203 } while (dtrace_casptr(&dcpu->dtdsc_dirty, free, dvar) != free);
2204
2205 goto top;
2206 }
2207
2208 /*ARGSUSED*/
2209 static void
2210 dtrace_aggregate_min(uint64_t *oval, uint64_t nval, uint64_t arg)
2211 {
2212 if ((int64_t)nval < (int64_t)*oval)
2213 *oval = nval;
2214 }
2215
2216 /*ARGSUSED*/
2217 static void
2218 dtrace_aggregate_max(uint64_t *oval, uint64_t nval, uint64_t arg)
2219 {
2220 if ((int64_t)nval > (int64_t)*oval)
2221 *oval = nval;
2222 }
2223
2224 static void
2225 dtrace_aggregate_quantize(uint64_t *quanta, uint64_t nval, uint64_t incr)
2226 {
2227 int i, zero = DTRACE_QUANTIZE_ZEROBUCKET;
2228 int64_t val = (int64_t)nval;
2229
2230 if (val < 0) {
2231 for (i = 0; i < zero; i++) {
2232 if (val <= DTRACE_QUANTIZE_BUCKETVAL(i)) {
2233 quanta[i] += incr;
2234 return;
2235 }
2236 }
2237 } else {
2238 for (i = zero + 1; i < DTRACE_QUANTIZE_NBUCKETS; i++) {
2239 if (val < DTRACE_QUANTIZE_BUCKETVAL(i)) {
2240 quanta[i - 1] += incr;
2241 return;
2242 }
2243 }
2244
2245 quanta[DTRACE_QUANTIZE_NBUCKETS - 1] += incr;
2246 return;
2247 }
2248
2249 ASSERT(0);
2250 }
2251
2252 static void
2253 dtrace_aggregate_lquantize(uint64_t *lquanta, uint64_t nval, uint64_t incr)
2254 {
2255 uint64_t arg = *lquanta++;
2256 int32_t base = DTRACE_LQUANTIZE_BASE(arg);
2257 uint16_t step = DTRACE_LQUANTIZE_STEP(arg);
2258 uint16_t levels = DTRACE_LQUANTIZE_LEVELS(arg);
2259 int32_t val = (int32_t)nval, level;
2260
2261 ASSERT(step != 0);
2262 ASSERT(levels != 0);
2263
2264 if (val < base) {
2265 /*
2266 * This is an underflow.
2267 */
2268 lquanta[0] += incr;
2269 return;
2270 }
2271
2272 level = (val - base) / step;
2273
2274 if (level < levels) {
2275 lquanta[level + 1] += incr;
2276 return;
2277 }
2278
2279 /*
2280 * This is an overflow.
2281 */
2282 lquanta[levels + 1] += incr;
2283 }
2284
2285 static int
2286 dtrace_aggregate_llquantize_bucket(uint16_t factor, uint16_t low,
2287 uint16_t high, uint16_t nsteps, int64_t value)
2288 {
2289 int64_t this = 1, last, next;
2290 int base = 1, order;
2291
2292 ASSERT(factor <= nsteps);
2293 ASSERT(nsteps % factor == 0);
2294
2295 for (order = 0; order < low; order++)
2296 this *= factor;
2297
2298 /*
2299 * If our value is less than our factor taken to the power of the
2300 * low order of magnitude, it goes into the zeroth bucket.
2301 */
2302 if (value < (last = this))
2303 return (0);
2304
2305 for (this *= factor; order <= high; order++) {
2306 int nbuckets = this > nsteps ? nsteps : this;
2307
2308 if ((next = this * factor) < this) {
2309 /*
2310 * We should not generally get log/linear quantizations
2311 * with a high magnitude that allows 64-bits to
2312 * overflow, but we nonetheless protect against this
2313 * by explicitly checking for overflow, and clamping
2314 * our value accordingly.
2315 */
2316 value = this - 1;
2317 }
2318
2319 if (value < this) {
2320 /*
2321 * If our value lies within this order of magnitude,
2322 * determine its position by taking the offset within
2323 * the order of magnitude, dividing by the bucket
2324 * width, and adding to our (accumulated) base.
2325 */
2326 return (base + (value - last) / (this / nbuckets));
2327 }
2328
2329 base += nbuckets - (nbuckets / factor);
2330 last = this;
2331 this = next;
2332 }
2333
2334 /*
2335 * Our value is greater than or equal to our factor taken to the
2336 * power of one plus the high magnitude -- return the top bucket.
2337 */
2338 return (base);
2339 }
2340
2341 static void
2342 dtrace_aggregate_llquantize(uint64_t *llquanta, uint64_t nval, uint64_t incr)
2343 {
2344 uint64_t arg = *llquanta++;
2345 uint16_t factor = DTRACE_LLQUANTIZE_FACTOR(arg);
2346 uint16_t low = DTRACE_LLQUANTIZE_LOW(arg);
2347 uint16_t high = DTRACE_LLQUANTIZE_HIGH(arg);
2348 uint16_t nsteps = DTRACE_LLQUANTIZE_NSTEP(arg);
2349
2350 llquanta[dtrace_aggregate_llquantize_bucket(factor,
2351 low, high, nsteps, nval)] += incr;
2352 }
2353
2354 /*ARGSUSED*/
2355 static void
2356 dtrace_aggregate_avg(uint64_t *data, uint64_t nval, uint64_t arg)
2357 {
2358 data[0]++;
2359 data[1] += nval;
2360 }
2361
2362 /*ARGSUSED*/
2363 static void
2364 dtrace_aggregate_stddev(uint64_t *data, uint64_t nval, uint64_t arg)
2365 {
2366 int64_t snval = (int64_t)nval;
2367 uint64_t tmp[2];
2368
2369 data[0]++;
2370 data[1] += nval;
2371
2372 /*
2373 * What we want to say here is:
2374 *
2375 * data[2] += nval * nval;
2376 *
2377 * But given that nval is 64-bit, we could easily overflow, so
2378 * we do this as 128-bit arithmetic.
2379 */
2380 if (snval < 0)
2381 snval = -snval;
2382
2383 dtrace_multiply_128((uint64_t)snval, (uint64_t)snval, tmp);
2384 dtrace_add_128(data + 2, tmp, data + 2);
2385 }
2386
2387 /*ARGSUSED*/
2388 static void
2389 dtrace_aggregate_count(uint64_t *oval, uint64_t nval, uint64_t arg)
2390 {
2391 *oval = *oval + 1;
2392 }
2393
2394 /*ARGSUSED*/
2395 static void
2396 dtrace_aggregate_sum(uint64_t *oval, uint64_t nval, uint64_t arg)
2397 {
2398 *oval += nval;
2399 }
2400
2401 /*
2402 * Aggregate given the tuple in the principal data buffer, and the aggregating
2403 * action denoted by the specified dtrace_aggregation_t. The aggregation
2404 * buffer is specified as the buf parameter. This routine does not return
2405 * failure; if there is no space in the aggregation buffer, the data will be
2406 * dropped, and a corresponding counter incremented.
2407 */
2408 static void
2409 dtrace_aggregate(dtrace_aggregation_t *agg, dtrace_buffer_t *dbuf,
2410 intptr_t offset, dtrace_buffer_t *buf, uint64_t expr, uint64_t arg)
2411 {
2412 dtrace_recdesc_t *rec = &agg->dtag_action.dta_rec;
2413 uint32_t i, ndx, size, fsize;
2414 uint32_t align = sizeof (uint64_t) - 1;
2415 dtrace_aggbuffer_t *agb;
2416 dtrace_aggkey_t *key;
2417 uint32_t hashval = 0, limit, isstr;
2418 caddr_t tomax, data, kdata;
2419 dtrace_actkind_t action;
2420 dtrace_action_t *act;
2421 uintptr_t offs;
2422
2423 if (buf == NULL)
2424 return;
2425
2426 if (!agg->dtag_hasarg) {
2427 /*
2428 * Currently, only quantize() and lquantize() take additional
2429 * arguments, and they have the same semantics: an increment
2430 * value that defaults to 1 when not present. If additional
2431 * aggregating actions take arguments, the setting of the
2432 * default argument value will presumably have to become more
2433 * sophisticated...
2434 */
2435 arg = 1;
2436 }
2437
2438 action = agg->dtag_action.dta_kind - DTRACEACT_AGGREGATION;
2439 size = rec->dtrd_offset - agg->dtag_base;
2440 fsize = size + rec->dtrd_size;
2441
2442 ASSERT(dbuf->dtb_tomax != NULL);
2443 data = dbuf->dtb_tomax + offset + agg->dtag_base;
2444
2445 if ((tomax = buf->dtb_tomax) == NULL) {
2446 dtrace_buffer_drop(buf);
2447 return;
2448 }
2449
2450 /*
2451 * The metastructure is always at the bottom of the buffer.
2452 */
2453 agb = (dtrace_aggbuffer_t *)(tomax + buf->dtb_size -
2454 sizeof (dtrace_aggbuffer_t));
2455
2456 if (buf->dtb_offset == 0) {
2457 /*
2458 * We just kludge up approximately 1/8th of the size to be
2459 * buckets. If this guess ends up being routinely
2460 * off-the-mark, we may need to dynamically readjust this
2461 * based on past performance.
2462 */
2463 uintptr_t hashsize = (buf->dtb_size >> 3) / sizeof (uintptr_t);
2464
2465 if ((uintptr_t)agb - hashsize * sizeof (dtrace_aggkey_t *) <
2466 (uintptr_t)tomax || hashsize == 0) {
2467 /*
2468 * We've been given a ludicrously small buffer;
2469 * increment our drop count and leave.
2470 */
2471 dtrace_buffer_drop(buf);
2472 return;
2473 }
2474
2475 /*
2476 * And now, a pathetic attempt to try to get a an odd (or
2477 * perchance, a prime) hash size for better hash distribution.
2478 */
2479 if (hashsize > (DTRACE_AGGHASHSIZE_SLEW << 3))
2480 hashsize -= DTRACE_AGGHASHSIZE_SLEW;
2481
2482 agb->dtagb_hashsize = hashsize;
2483 agb->dtagb_hash = (dtrace_aggkey_t **)((uintptr_t)agb -
2484 agb->dtagb_hashsize * sizeof (dtrace_aggkey_t *));
2485 agb->dtagb_free = (uintptr_t)agb->dtagb_hash;
2486
2487 for (i = 0; i < agb->dtagb_hashsize; i++)
2488 agb->dtagb_hash[i] = NULL;
2489 }
2490
2491 ASSERT(agg->dtag_first != NULL);
2492 ASSERT(agg->dtag_first->dta_intuple);
2493
2494 /*
2495 * Calculate the hash value based on the key. Note that we _don't_
2496 * include the aggid in the hashing (but we will store it as part of
2497 * the key). The hashing algorithm is Bob Jenkins' "One-at-a-time"
2498 * algorithm: a simple, quick algorithm that has no known funnels, and
2499 * gets good distribution in practice. The efficacy of the hashing
2500 * algorithm (and a comparison with other algorithms) may be found by
2501 * running the ::dtrace_aggstat MDB dcmd.
2502 */
2503 for (act = agg->dtag_first; act->dta_intuple; act = act->dta_next) {
2504 i = act->dta_rec.dtrd_offset - agg->dtag_base;
2505 limit = i + act->dta_rec.dtrd_size;
2506 ASSERT(limit <= size);
2507 isstr = DTRACEACT_ISSTRING(act);
2508
2509 for (; i < limit; i++) {
2510 hashval += data[i];
2511 hashval += (hashval << 10);
2512 hashval ^= (hashval >> 6);
2513
2514 if (isstr && data[i] == '\0')
2515 break;
2516 }
2517 }
2518
2519 hashval += (hashval << 3);
2520 hashval ^= (hashval >> 11);
2521 hashval += (hashval << 15);
2522
2523 /*
2524 * Yes, the divide here is expensive -- but it's generally the least
2525 * of the performance issues given the amount of data that we iterate
2526 * over to compute hash values, compare data, etc.
2527 */
2528 ndx = hashval % agb->dtagb_hashsize;
2529
2530 for (key = agb->dtagb_hash[ndx]; key != NULL; key = key->dtak_next) {
2531 ASSERT((caddr_t)key >= tomax);
2532 ASSERT((caddr_t)key < tomax + buf->dtb_size);
2533
2534 if (hashval != key->dtak_hashval || key->dtak_size != size)
2535 continue;
2536
2537 kdata = key->dtak_data;
2538 ASSERT(kdata >= tomax && kdata < tomax + buf->dtb_size);
2539
2540 for (act = agg->dtag_first; act->dta_intuple;
2541 act = act->dta_next) {
2542 i = act->dta_rec.dtrd_offset - agg->dtag_base;
2543 limit = i + act->dta_rec.dtrd_size;
2544 ASSERT(limit <= size);
2545 isstr = DTRACEACT_ISSTRING(act);
2546
2547 for (; i < limit; i++) {
2548 if (kdata[i] != data[i])
2549 goto next;
2550
2551 if (isstr && data[i] == '\0')
2552 break;
2553 }
2554 }
2555
2556 if (action != key->dtak_action) {
2557 /*
2558 * We are aggregating on the same value in the same
2559 * aggregation with two different aggregating actions.
2560 * (This should have been picked up in the compiler,
2561 * so we may be dealing with errant or devious DIF.)
2562 * This is an error condition; we indicate as much,
2563 * and return.
2564 */
2565 DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP);
2566 return;
2567 }
2568
2569 /*
2570 * This is a hit: we need to apply the aggregator to
2571 * the value at this key.
2572 */
2573 agg->dtag_aggregate((uint64_t *)(kdata + size), expr, arg);
2574 return;
2575 next:
2576 continue;
2577 }
2578
2579 /*
2580 * We didn't find it. We need to allocate some zero-filled space,
2581 * link it into the hash table appropriately, and apply the aggregator
2582 * to the (zero-filled) value.
2583 */
2584 offs = buf->dtb_offset;
2585 while (offs & (align - 1))
2586 offs += sizeof (uint32_t);
2587
2588 /*
2589 * If we don't have enough room to both allocate a new key _and_
2590 * its associated data, increment the drop count and return.
2591 */
2592 if ((uintptr_t)tomax + offs + fsize >
2593 agb->dtagb_free - sizeof (dtrace_aggkey_t)) {
2594 dtrace_buffer_drop(buf);
2595 return;
2596 }
2597
2598 /*CONSTCOND*/
2599 ASSERT(!(sizeof (dtrace_aggkey_t) & (sizeof (uintptr_t) - 1)));
2600 key = (dtrace_aggkey_t *)(agb->dtagb_free - sizeof (dtrace_aggkey_t));
2601 agb->dtagb_free -= sizeof (dtrace_aggkey_t);
2602
2603 key->dtak_data = kdata = tomax + offs;
2604 buf->dtb_offset = offs + fsize;
2605
2606 /*
2607 * Now copy the data across.
2608 */
2609 *((dtrace_aggid_t *)kdata) = agg->dtag_id;
2610
2611 for (i = sizeof (dtrace_aggid_t); i < size; i++)
2612 kdata[i] = data[i];
2613
2614 /*
2615 * Because strings are not zeroed out by default, we need to iterate
2616 * looking for actions that store strings, and we need to explicitly
2617 * pad these strings out with zeroes.
2618 */
2619 for (act = agg->dtag_first; act->dta_intuple; act = act->dta_next) {
2620 int nul;
2621
2622 if (!DTRACEACT_ISSTRING(act))
2623 continue;
2624
2625 i = act->dta_rec.dtrd_offset - agg->dtag_base;
2626 limit = i + act->dta_rec.dtrd_size;
2627 ASSERT(limit <= size);
2628
2629 for (nul = 0; i < limit; i++) {
2630 if (nul) {
2631 kdata[i] = '\0';
2632 continue;
2633 }
2634
2635 if (data[i] != '\0')
2636 continue;
2637
2638 nul = 1;
2639 }
2640 }
2641
2642 for (i = size; i < fsize; i++)
2643 kdata[i] = 0;
2644
2645 key->dtak_hashval = hashval;
2646 key->dtak_size = size;
2647 key->dtak_action = action;
2648 key->dtak_next = agb->dtagb_hash[ndx];
2649 agb->dtagb_hash[ndx] = key;
2650
2651 /*
2652 * Finally, apply the aggregator.
2653 */
2654 *((uint64_t *)(key->dtak_data + size)) = agg->dtag_initial;
2655 agg->dtag_aggregate((uint64_t *)(key->dtak_data + size), expr, arg);
2656 }
2657
2658 /*
2659 * Given consumer state, this routine finds a speculation in the INACTIVE
2660 * state and transitions it into the ACTIVE state. If there is no speculation
2661 * in the INACTIVE state, 0 is returned. In this case, no error counter is
2662 * incremented -- it is up to the caller to take appropriate action.
2663 */
2664 static int
2665 dtrace_speculation(dtrace_state_t *state)
2666 {
2667 int i = 0;
2668 dtrace_speculation_state_t current;
2669 uint32_t *stat = &state->dts_speculations_unavail, count;
2670
2671 while (i < state->dts_nspeculations) {
2672 dtrace_speculation_t *spec = &state->dts_speculations[i];
2673
2674 current = spec->dtsp_state;
2675
2676 if (current != DTRACESPEC_INACTIVE) {
2677 if (current == DTRACESPEC_COMMITTINGMANY ||
2678 current == DTRACESPEC_COMMITTING ||
2679 current == DTRACESPEC_DISCARDING)
2680 stat = &state->dts_speculations_busy;
2681 i++;
2682 continue;
2683 }
2684
2685 if (dtrace_cas32((uint32_t *)&spec->dtsp_state,
2686 current, DTRACESPEC_ACTIVE) == current)
2687 return (i + 1);
2688 }
2689
2690 /*
2691 * We couldn't find a speculation. If we found as much as a single
2692 * busy speculation buffer, we'll attribute this failure as "busy"
2693 * instead of "unavail".
2694 */
2695 do {
2696 count = *stat;
2697 } while (dtrace_cas32(stat, count, count + 1) != count);
2698
2699 return (0);
2700 }
2701
2702 /*
2703 * This routine commits an active speculation. If the specified speculation
2704 * is not in a valid state to perform a commit(), this routine will silently do
2705 * nothing. The state of the specified speculation is transitioned according
2706 * to the state transition diagram outlined in <sys/dtrace_impl.h>
2707 */
2708 static void
2709 dtrace_speculation_commit(dtrace_state_t *state, processorid_t cpu,
2710 dtrace_specid_t which)
2711 {
2712 dtrace_speculation_t *spec;
2713 dtrace_buffer_t *src, *dest;
2714 uintptr_t daddr, saddr, dlimit, slimit;
2715 dtrace_speculation_state_t current, new;
2716 intptr_t offs;
2717 uint64_t timestamp;
2718
2719 if (which == 0)
2720 return;
2721
2722 if (which > state->dts_nspeculations) {
2723 cpu_core[cpu].cpuc_dtrace_flags |= CPU_DTRACE_ILLOP;
2724 return;
2725 }
2726
2727 spec = &state->dts_speculations[which - 1];
2728 src = &spec->dtsp_buffer[cpu];
2729 dest = &state->dts_buffer[cpu];
2730
2731 do {
2732 current = spec->dtsp_state;
2733
2734 if (current == DTRACESPEC_COMMITTINGMANY)
2735 break;
2736
2737 switch (current) {
2738 case DTRACESPEC_INACTIVE:
2739 case DTRACESPEC_DISCARDING:
2740 return;
2741
2742 case DTRACESPEC_COMMITTING:
2743 /*
2744 * This is only possible if we are (a) commit()'ing
2745 * without having done a prior speculate() on this CPU
2746 * and (b) racing with another commit() on a different
2747 * CPU. There's nothing to do -- we just assert that
2748 * our offset is 0.
2749 */
2750 ASSERT(src->dtb_offset == 0);
2751 return;
2752
2753 case DTRACESPEC_ACTIVE:
2754 new = DTRACESPEC_COMMITTING;
2755 break;
2756
2757 case DTRACESPEC_ACTIVEONE:
2758 /*
2759 * This speculation is active on one CPU. If our
2760 * buffer offset is non-zero, we know that the one CPU
2761 * must be us. Otherwise, we are committing on a
2762 * different CPU from the speculate(), and we must
2763 * rely on being asynchronously cleaned.
2764 */
2765 if (src->dtb_offset != 0) {
2766 new = DTRACESPEC_COMMITTING;
2767 break;
2768 }
2769 /*FALLTHROUGH*/
2770
2771 case DTRACESPEC_ACTIVEMANY:
2772 new = DTRACESPEC_COMMITTINGMANY;
2773 break;
2774
2775 default:
2776 ASSERT(0);
2777 }
2778 } while (dtrace_cas32((uint32_t *)&spec->dtsp_state,
2779 current, new) != current);
2780
2781 /*
2782 * We have set the state to indicate that we are committing this
2783 * speculation. Now reserve the necessary space in the destination
2784 * buffer.
2785 */
2786 if ((offs = dtrace_buffer_reserve(dest, src->dtb_offset,
2787 sizeof (uint64_t), state, NULL)) < 0) {
2788 dtrace_buffer_drop(dest);
2789 goto out;
2790 }
2791
2792 /*
2793 * We have sufficient space to copy the speculative buffer into the
2794 * primary buffer. First, modify the speculative buffer, filling
2795 * in the timestamp of all entries with the current time. The data
2796 * must have the commit() time rather than the time it was traced,
2797 * so that all entries in the primary buffer are in timestamp order.
2798 */
2799 timestamp = dtrace_gethrtime();
2800 saddr = (uintptr_t)src->dtb_tomax;
2801 slimit = saddr + src->dtb_offset;
2802 while (saddr < slimit) {
2803 size_t size;
2804 dtrace_rechdr_t *dtrh = (dtrace_rechdr_t *)saddr;
2805
2806 if (dtrh->dtrh_epid == DTRACE_EPIDNONE) {
2807 saddr += sizeof (dtrace_epid_t);
2808 continue;
2809 }
2810 ASSERT3U(dtrh->dtrh_epid, <=, state->dts_necbs);
2811 size = state->dts_ecbs[dtrh->dtrh_epid - 1]->dte_size;
2812
2813 ASSERT3U(saddr + size, <=, slimit);
2814 ASSERT3U(size, >=, sizeof (dtrace_rechdr_t));
2815 ASSERT3U(DTRACE_RECORD_LOAD_TIMESTAMP(dtrh), ==, UINT64_MAX);
2816
2817 DTRACE_RECORD_STORE_TIMESTAMP(dtrh, timestamp);
2818
2819 saddr += size;
2820 }
2821
2822 /*
2823 * Copy the buffer across. (Note that this is a
2824 * highly subobtimal bcopy(); in the unlikely event that this becomes
2825 * a serious performance issue, a high-performance DTrace-specific
2826 * bcopy() should obviously be invented.)
2827 */
2828 daddr = (uintptr_t)dest->dtb_tomax + offs;
2829 dlimit = daddr + src->dtb_offset;
2830 saddr = (uintptr_t)src->dtb_tomax;
2831
2832 /*
2833 * First, the aligned portion.
2834 */
2835 while (dlimit - daddr >= sizeof (uint64_t)) {
2836 *((uint64_t *)daddr) = *((uint64_t *)saddr);
2837
2838 daddr += sizeof (uint64_t);
2839 saddr += sizeof (uint64_t);
2840 }
2841
2842 /*
2843 * Now any left-over bit...
2844 */
2845 while (dlimit - daddr)
2846 *((uint8_t *)daddr++) = *((uint8_t *)saddr++);
2847
2848 /*
2849 * Finally, commit the reserved space in the destination buffer.
2850 */
2851 dest->dtb_offset = offs + src->dtb_offset;
2852
2853 out:
2854 /*
2855 * If we're lucky enough to be the only active CPU on this speculation
2856 * buffer, we can just set the state back to DTRACESPEC_INACTIVE.
2857 */
2858 if (current == DTRACESPEC_ACTIVE ||
2859 (current == DTRACESPEC_ACTIVEONE && new == DTRACESPEC_COMMITTING)) {
2860 uint32_t rval = dtrace_cas32((uint32_t *)&spec->dtsp_state,
2861 DTRACESPEC_COMMITTING, DTRACESPEC_INACTIVE);
2862
2863 ASSERT(rval == DTRACESPEC_COMMITTING);
2864 }
2865
2866 src->dtb_offset = 0;
2867 src->dtb_xamot_drops += src->dtb_drops;
2868 src->dtb_drops = 0;
2869 }
2870
2871 /*
2872 * This routine discards an active speculation. If the specified speculation
2873 * is not in a valid state to perform a discard(), this routine will silently
2874 * do nothing. The state of the specified speculation is transitioned
2875 * according to the state transition diagram outlined in <sys/dtrace_impl.h>
2876 */
2877 static void
2878 dtrace_speculation_discard(dtrace_state_t *state, processorid_t cpu,
2879 dtrace_specid_t which)
2880 {
2881 dtrace_speculation_t *spec;
2882 dtrace_speculation_state_t current, new;
2883 dtrace_buffer_t *buf;
2884
2885 if (which == 0)
2886 return;
2887
2888 if (which > state->dts_nspeculations) {
2889 cpu_core[cpu].cpuc_dtrace_flags |= CPU_DTRACE_ILLOP;
2890 return;
2891 }
2892
2893 spec = &state->dts_speculations[which - 1];
2894 buf = &spec->dtsp_buffer[cpu];
2895
2896 do {
2897 current = spec->dtsp_state;
2898
2899 switch (current) {
2900 case DTRACESPEC_INACTIVE:
2901 case DTRACESPEC_COMMITTINGMANY:
2902 case DTRACESPEC_COMMITTING:
2903 case DTRACESPEC_DISCARDING:
2904 return;
2905
2906 case DTRACESPEC_ACTIVE:
2907 case DTRACESPEC_ACTIVEMANY:
2908 new = DTRACESPEC_DISCARDING;
2909 break;
2910
2911 case DTRACESPEC_ACTIVEONE:
2912 if (buf->dtb_offset != 0) {
2913 new = DTRACESPEC_INACTIVE;
2914 } else {
2915 new = DTRACESPEC_DISCARDING;
2916 }
2917 break;
2918
2919 default:
2920 ASSERT(0);
2921 }
2922 } while (dtrace_cas32((uint32_t *)&spec->dtsp_state,
2923 current, new) != current);
2924
2925 buf->dtb_offset = 0;
2926 buf->dtb_drops = 0;
2927 }
2928
2929 /*
2930 * Note: not called from probe context. This function is called
2931 * asynchronously from cross call context to clean any speculations that are
2932 * in the COMMITTINGMANY or DISCARDING states. These speculations may not be
2933 * transitioned back to the INACTIVE state until all CPUs have cleaned the
2934 * speculation.
2935 */
2936 static void
2937 dtrace_speculation_clean_here(dtrace_state_t *state)
2938 {
2939 dtrace_icookie_t cookie;
2940 processorid_t cpu = CPU->cpu_id;
2941 dtrace_buffer_t *dest = &state->dts_buffer[cpu];
2942 dtrace_specid_t i;
2943
2944 cookie = dtrace_interrupt_disable();
2945
2946 if (dest->dtb_tomax == NULL) {
2947 dtrace_interrupt_enable(cookie);
2948 return;
2949 }
2950
2951 for (i = 0; i < state->dts_nspeculations; i++) {
2952 dtrace_speculation_t *spec = &state->dts_speculations[i];
2953 dtrace_buffer_t *src = &spec->dtsp_buffer[cpu];
2954
2955 if (src->dtb_tomax == NULL)
2956 continue;
2957
2958 if (spec->dtsp_state == DTRACESPEC_DISCARDING) {
2959 src->dtb_offset = 0;
2960 continue;
2961 }
2962
2963 if (spec->dtsp_state != DTRACESPEC_COMMITTINGMANY)
2964 continue;
2965
2966 if (src->dtb_offset == 0)
2967 continue;
2968
2969 dtrace_speculation_commit(state, cpu, i + 1);
2970 }
2971
2972 dtrace_interrupt_enable(cookie);
2973 }
2974
2975 /*
2976 * Note: not called from probe context. This function is called
2977 * asynchronously (and at a regular interval) to clean any speculations that
2978 * are in the COMMITTINGMANY or DISCARDING states. If it discovers that there
2979 * is work to be done, it cross calls all CPUs to perform that work;
2980 * COMMITMANY and DISCARDING speculations may not be transitioned back to the
2981 * INACTIVE state until they have been cleaned by all CPUs.
2982 */
2983 static void
2984 dtrace_speculation_clean(dtrace_state_t *state)
2985 {
2986 int work = 0, rv;
2987 dtrace_specid_t i;
2988
2989 for (i = 0; i < state->dts_nspeculations; i++) {
2990 dtrace_speculation_t *spec = &state->dts_speculations[i];
2991
2992 ASSERT(!spec->dtsp_cleaning);
2993
2994 if (spec->dtsp_state != DTRACESPEC_DISCARDING &&
2995 spec->dtsp_state != DTRACESPEC_COMMITTINGMANY)
2996 continue;
2997
2998 work++;
2999 spec->dtsp_cleaning = 1;
3000 }
3001
3002 if (!work)
3003 return;
3004
3005 dtrace_xcall(DTRACE_CPUALL,
3006 (dtrace_xcall_t)dtrace_speculation_clean_here, state);
3007
3008 /*
3009 * We now know that all CPUs have committed or discarded their
3010 * speculation buffers, as appropriate. We can now set the state
3011 * to inactive.
3012 */
3013 for (i = 0; i < state->dts_nspeculations; i++) {
3014 dtrace_speculation_t *spec = &state->dts_speculations[i];
3015 dtrace_speculation_state_t current, new;
3016
3017 if (!spec->dtsp_cleaning)
3018 continue;
3019
3020 current = spec->dtsp_state;
3021 ASSERT(current == DTRACESPEC_DISCARDING ||
3022 current == DTRACESPEC_COMMITTINGMANY);
3023
3024 new = DTRACESPEC_INACTIVE;
3025
3026 rv = dtrace_cas32((uint32_t *)&spec->dtsp_state, current, new);
3027 ASSERT(rv == current);
3028 spec->dtsp_cleaning = 0;
3029 }
3030 }
3031
3032 /*
3033 * Called as part of a speculate() to get the speculative buffer associated
3034 * with a given speculation. Returns NULL if the specified speculation is not
3035 * in an ACTIVE state. If the speculation is in the ACTIVEONE state -- and
3036 * the active CPU is not the specified CPU -- the speculation will be
3037 * atomically transitioned into the ACTIVEMANY state.
3038 */
3039 static dtrace_buffer_t *
3040 dtrace_speculation_buffer(dtrace_state_t *state, processorid_t cpuid,
3041 dtrace_specid_t which)
3042 {
3043 dtrace_speculation_t *spec;
3044 dtrace_speculation_state_t current, new;
3045 dtrace_buffer_t *buf;
3046
3047 if (which == 0)
3048 return (NULL);
3049
3050 if (which > state->dts_nspeculations) {
3051 cpu_core[cpuid].cpuc_dtrace_flags |= CPU_DTRACE_ILLOP;
3052 return (NULL);
3053 }
3054
3055 spec = &state->dts_speculations[which - 1];
3056 buf = &spec->dtsp_buffer[cpuid];
3057
3058 do {
3059 current = spec->dtsp_state;
3060
3061 switch (current) {
3062 case DTRACESPEC_INACTIVE:
3063 case DTRACESPEC_COMMITTINGMANY:
3064 case DTRACESPEC_DISCARDING:
3065 return (NULL);
3066
3067 case DTRACESPEC_COMMITTING:
3068 ASSERT(buf->dtb_offset == 0);
3069 return (NULL);
3070
3071 case DTRACESPEC_ACTIVEONE:
3072 /*
3073 * This speculation is currently active on one CPU.
3074 * Check the offset in the buffer; if it's non-zero,
3075 * that CPU must be us (and we leave the state alone).
3076 * If it's zero, assume that we're starting on a new
3077 * CPU -- and change the state to indicate that the
3078 * speculation is active on more than one CPU.
3079 */
3080 if (buf->dtb_offset != 0)
3081 return (buf);
3082
3083 new = DTRACESPEC_ACTIVEMANY;
3084 break;
3085
3086 case DTRACESPEC_ACTIVEMANY:
3087 return (buf);
3088
3089 case DTRACESPEC_ACTIVE:
3090 new = DTRACESPEC_ACTIVEONE;
3091 break;
3092
3093 default:
3094 ASSERT(0);
3095 }
3096 } while (dtrace_cas32((uint32_t *)&spec->dtsp_state,
3097 current, new) != current);
3098
3099 ASSERT(new == DTRACESPEC_ACTIVEONE || new == DTRACESPEC_ACTIVEMANY);
3100 return (buf);
3101 }
3102
3103 /*
3104 * Return a string. In the event that the user lacks the privilege to access
3105 * arbitrary kernel memory, we copy the string out to scratch memory so that we
3106 * don't fail access checking.
3107 *
3108 * dtrace_dif_variable() uses this routine as a helper for various
3109 * builtin values such as 'execname' and 'probefunc.'
3110 */
3111 uintptr_t
3112 dtrace_dif_varstr(uintptr_t addr, dtrace_state_t *state,
3113 dtrace_mstate_t *mstate)
3114 {
3115 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
3116 uintptr_t ret;
3117 size_t strsz;
3118
3119 /*
3120 * The easy case: this probe is allowed to read all of memory, so
3121 * we can just return this as a vanilla pointer.
3122 */
3123 if ((mstate->dtms_access & DTRACE_ACCESS_KERNEL) != 0)
3124 return (addr);
3125
3126 /*
3127 * This is the tougher case: we copy the string in question from
3128 * kernel memory into scratch memory and return it that way: this
3129 * ensures that we won't trip up when access checking tests the
3130 * BYREF return value.
3131 */
3132 strsz = dtrace_strlen((char *)addr, size) + 1;
3133
3134 if (mstate->dtms_scratch_ptr + strsz >
3135 mstate->dtms_scratch_base + mstate->dtms_scratch_size) {
3136 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
3137 return (NULL);
3138 }
3139
3140 dtrace_strcpy((const void *)addr, (void *)mstate->dtms_scratch_ptr,
3141 strsz);
3142 ret = mstate->dtms_scratch_ptr;
3143 mstate->dtms_scratch_ptr += strsz;
3144 return (ret);
3145 }
3146
3147 /*
3148 * This function implements the DIF emulator's variable lookups. The emulator
3149 * passes a reserved variable identifier and optional built-in array index.
3150 */
3151 static uint64_t
3152 dtrace_dif_variable(dtrace_mstate_t *mstate, dtrace_state_t *state, uint64_t v,
3153 uint64_t ndx)
3154 {
3155 /*
3156 * If we're accessing one of the uncached arguments, we'll turn this
3157 * into a reference in the args array.
3158 */
3159 if (v >= DIF_VAR_ARG0 && v <= DIF_VAR_ARG9) {
3160 ndx = v - DIF_VAR_ARG0;
3161 v = DIF_VAR_ARGS;
3162 }
3163
3164 switch (v) {
3165 case DIF_VAR_ARGS:
3166 if (!(mstate->dtms_access & DTRACE_ACCESS_ARGS)) {
3167 cpu_core[CPU->cpu_id].cpuc_dtrace_flags |=
3168 CPU_DTRACE_KPRIV;
3169 return (0);
3170 }
3171
3172 ASSERT(mstate->dtms_present & DTRACE_MSTATE_ARGS);
3173 if (ndx >= sizeof (mstate->dtms_arg) /
3174 sizeof (mstate->dtms_arg[0])) {
3175 int aframes = mstate->dtms_probe->dtpr_aframes + 2;
3176 dtrace_provider_t *pv;
3177 uint64_t val;
3178
3179 pv = mstate->dtms_probe->dtpr_provider;
3180 if (pv->dtpv_pops.dtps_getargval != NULL)
3181 val = pv->dtpv_pops.dtps_getargval(pv->dtpv_arg,
3182 mstate->dtms_probe->dtpr_id,
3183 mstate->dtms_probe->dtpr_arg, ndx, aframes);
3184 else
3185 val = dtrace_getarg(ndx, aframes);
3186
3187 /*
3188 * This is regrettably required to keep the compiler
3189 * from tail-optimizing the call to dtrace_getarg().
3190 * The condition always evaluates to true, but the
3191 * compiler has no way of figuring that out a priori.
3192 * (None of this would be necessary if the compiler
3193 * could be relied upon to _always_ tail-optimize
3194 * the call to dtrace_getarg() -- but it can't.)
3195 */
3196 if (mstate->dtms_probe != NULL)
3197 return (val);
3198
3199 ASSERT(0);
3200 }
3201
3202 return (mstate->dtms_arg[ndx]);
3203
3204 case DIF_VAR_UREGS: {
3205 klwp_t *lwp;
3206
3207 if (!dtrace_priv_proc(state, mstate))
3208 return (0);
3209
3210 if ((lwp = curthread->t_lwp) == NULL) {
3211 DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR);
3212 cpu_core[CPU->cpu_id].cpuc_dtrace_illval = NULL;
3213 return (0);
3214 }
3215
3216 return (dtrace_getreg(lwp->lwp_regs, ndx));
3217 }
3218
3219 case DIF_VAR_VMREGS: {
3220 uint64_t rval;
3221
3222 if (!dtrace_priv_kernel(state))
3223 return (0);
3224
3225 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
3226
3227 rval = dtrace_getvmreg(ndx,
3228 &cpu_core[CPU->cpu_id].cpuc_dtrace_flags);
3229
3230 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
3231
3232 return (rval);
3233 }
3234
3235 case DIF_VAR_CURTHREAD:
3236 if (!dtrace_priv_proc(state, mstate))
3237 return (0);
3238 return ((uint64_t)(uintptr_t)curthread);
3239
3240 case DIF_VAR_TIMESTAMP:
3241 if (!(mstate->dtms_present & DTRACE_MSTATE_TIMESTAMP)) {
3242 mstate->dtms_timestamp = dtrace_gethrtime();
3243 mstate->dtms_present |= DTRACE_MSTATE_TIMESTAMP;
3244 }
3245 return (mstate->dtms_timestamp);
3246
3247 case DIF_VAR_VTIMESTAMP:
3248 ASSERT(dtrace_vtime_references != 0);
3249 return (curthread->t_dtrace_vtime);
3250
3251 case DIF_VAR_WALLTIMESTAMP:
3252 if (!(mstate->dtms_present & DTRACE_MSTATE_WALLTIMESTAMP)) {
3253 mstate->dtms_walltimestamp = dtrace_gethrestime();
3254 mstate->dtms_present |= DTRACE_MSTATE_WALLTIMESTAMP;
3255 }
3256 return (mstate->dtms_walltimestamp);
3257
3258 case DIF_VAR_IPL:
3259 if (!dtrace_priv_kernel(state))
3260 return (0);
3261 if (!(mstate->dtms_present & DTRACE_MSTATE_IPL)) {
3262 mstate->dtms_ipl = dtrace_getipl();
3263 mstate->dtms_present |= DTRACE_MSTATE_IPL;
3264 }
3265 return (mstate->dtms_ipl);
3266
3267 case DIF_VAR_EPID:
3268 ASSERT(mstate->dtms_present & DTRACE_MSTATE_EPID);
3269 return (mstate->dtms_epid);
3270
3271 case DIF_VAR_ID:
3272 ASSERT(mstate->dtms_present & DTRACE_MSTATE_PROBE);
3273 return (mstate->dtms_probe->dtpr_id);
3274
3275 case DIF_VAR_STACKDEPTH:
3276 if (!dtrace_priv_kernel(state))
3277 return (0);
3278 if (!(mstate->dtms_present & DTRACE_MSTATE_STACKDEPTH)) {
3279 int aframes = mstate->dtms_probe->dtpr_aframes + 2;
3280
3281 mstate->dtms_stackdepth = dtrace_getstackdepth(aframes);
3282 mstate->dtms_present |= DTRACE_MSTATE_STACKDEPTH;
3283 }
3284 return (mstate->dtms_stackdepth);
3285
3286 case DIF_VAR_USTACKDEPTH:
3287 if (!dtrace_priv_proc(state, mstate))
3288 return (0);
3289 if (!(mstate->dtms_present & DTRACE_MSTATE_USTACKDEPTH)) {
3290 /*
3291 * See comment in DIF_VAR_PID.
3292 */
3293 if (DTRACE_ANCHORED(mstate->dtms_probe) &&
3294 CPU_ON_INTR(CPU)) {
3295 mstate->dtms_ustackdepth = 0;
3296 } else {
3297 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
3298 mstate->dtms_ustackdepth =
3299 dtrace_getustackdepth();
3300 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
3301 }
3302 mstate->dtms_present |= DTRACE_MSTATE_USTACKDEPTH;
3303 }
3304 return (mstate->dtms_ustackdepth);
3305
3306 case DIF_VAR_CALLER:
3307 if (!dtrace_priv_kernel(state))
3308 return (0);
3309 if (!(mstate->dtms_present & DTRACE_MSTATE_CALLER)) {
3310 int aframes = mstate->dtms_probe->dtpr_aframes + 2;
3311
3312 if (!DTRACE_ANCHORED(mstate->dtms_probe)) {
3313 /*
3314 * If this is an unanchored probe, we are
3315 * required to go through the slow path:
3316 * dtrace_caller() only guarantees correct
3317 * results for anchored probes.
3318 */
3319 pc_t caller[2];
3320
3321 dtrace_getpcstack(caller, 2, aframes,
3322 (uint32_t *)(uintptr_t)mstate->dtms_arg[0]);
3323 mstate->dtms_caller = caller[1];
3324 } else if ((mstate->dtms_caller =
3325 dtrace_caller(aframes)) == -1) {
3326 /*
3327 * We have failed to do this the quick way;
3328 * we must resort to the slower approach of
3329 * calling dtrace_getpcstack().
3330 */
3331 pc_t caller;
3332
3333 dtrace_getpcstack(&caller, 1, aframes, NULL);
3334 mstate->dtms_caller = caller;
3335 }
3336
3337 mstate->dtms_present |= DTRACE_MSTATE_CALLER;
3338 }
3339 return (mstate->dtms_caller);
3340
3341 case DIF_VAR_UCALLER:
3342 if (!dtrace_priv_proc(state, mstate))
3343 return (0);
3344
3345 if (!(mstate->dtms_present & DTRACE_MSTATE_UCALLER)) {
3346 uint64_t ustack[3];
3347
3348 /*
3349 * dtrace_getupcstack() fills in the first uint64_t
3350 * with the current PID. The second uint64_t will
3351 * be the program counter at user-level. The third
3352 * uint64_t will contain the caller, which is what
3353 * we're after.
3354 */
3355 ustack[2] = NULL;
3356 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
3357 dtrace_getupcstack(ustack, 3);
3358 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
3359 mstate->dtms_ucaller = ustack[2];
3360 mstate->dtms_present |= DTRACE_MSTATE_UCALLER;
3361 }
3362
3363 return (mstate->dtms_ucaller);
3364
3365 case DIF_VAR_PROBEPROV:
3366 ASSERT(mstate->dtms_present & DTRACE_MSTATE_PROBE);
3367 return (dtrace_dif_varstr(
3368 (uintptr_t)mstate->dtms_probe->dtpr_provider->dtpv_name,
3369 state, mstate));
3370
3371 case DIF_VAR_PROBEMOD:
3372 ASSERT(mstate->dtms_present & DTRACE_MSTATE_PROBE);
3373 return (dtrace_dif_varstr(
3374 (uintptr_t)mstate->dtms_probe->dtpr_mod,
3375 state, mstate));
3376
3377 case DIF_VAR_PROBEFUNC:
3378 ASSERT(mstate->dtms_present & DTRACE_MSTATE_PROBE);
3379 return (dtrace_dif_varstr(
3380 (uintptr_t)mstate->dtms_probe->dtpr_func,
3381 state, mstate));
3382
3383 case DIF_VAR_PROBENAME:
3384 ASSERT(mstate->dtms_present & DTRACE_MSTATE_PROBE);
3385 return (dtrace_dif_varstr(
3386 (uintptr_t)mstate->dtms_probe->dtpr_name,
3387 state, mstate));
3388
3389 case DIF_VAR_PID:
3390 if (!dtrace_priv_proc(state, mstate))
3391 return (0);
3392
3393 /*
3394 * Note that we are assuming that an unanchored probe is
3395 * always due to a high-level interrupt. (And we're assuming
3396 * that there is only a single high level interrupt.)
3397 */
3398 if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU))
3399 return (pid0.pid_id);
3400
3401 /*
3402 * It is always safe to dereference one's own t_procp pointer:
3403 * it always points to a valid, allocated proc structure.
3404 * Further, it is always safe to dereference the p_pidp member
3405 * of one's own proc structure. (These are truisms becuase
3406 * threads and processes don't clean up their own state --
3407 * they leave that task to whomever reaps them.)
3408 */
3409 return ((uint64_t)curthread->t_procp->p_pidp->pid_id);
3410
3411 case DIF_VAR_PPID:
3412 if (!dtrace_priv_proc(state, mstate))
3413 return (0);
3414
3415 /*
3416 * See comment in DIF_VAR_PID.
3417 */
3418 if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU))
3419 return (pid0.pid_id);
3420
3421 /*
3422 * It is always safe to dereference one's own t_procp pointer:
3423 * it always points to a valid, allocated proc structure.
3424 * (This is true because threads don't clean up their own
3425 * state -- they leave that task to whomever reaps them.)
3426 */
3427 return ((uint64_t)curthread->t_procp->p_ppid);
3428
3429 case DIF_VAR_TID:
3430 /*
3431 * See comment in DIF_VAR_PID.
3432 */
3433 if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU))
3434 return (0);
3435
3436 return ((uint64_t)curthread->t_tid);
3437
3438 case DIF_VAR_EXECNAME:
3439 if (!dtrace_priv_proc(state, mstate))
3440 return (0);
3441
3442 /*
3443 * See comment in DIF_VAR_PID.
3444 */
3445 if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU))
3446 return ((uint64_t)(uintptr_t)p0.p_user.u_comm);
3447
3448 /*
3449 * It is always safe to dereference one's own t_procp pointer:
3450 * it always points to a valid, allocated proc structure.
3451 * (This is true because threads don't clean up their own
3452 * state -- they leave that task to whomever reaps them.)
3453 */
3454 return (dtrace_dif_varstr(
3455 (uintptr_t)curthread->t_procp->p_user.u_comm,
3456 state, mstate));
3457
3458 case DIF_VAR_ZONENAME:
3459 if (!dtrace_priv_proc(state, mstate))
3460 return (0);
3461
3462 /*
3463 * See comment in DIF_VAR_PID.
3464 */
3465 if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU))
3466 return ((uint64_t)(uintptr_t)p0.p_zone->zone_name);
3467
3468 /*
3469 * It is always safe to dereference one's own t_procp pointer:
3470 * it always points to a valid, allocated proc structure.
3471 * (This is true because threads don't clean up their own
3472 * state -- they leave that task to whomever reaps them.)
3473 */
3474 return (dtrace_dif_varstr(
3475 (uintptr_t)curthread->t_procp->p_zone->zone_name,
3476 state, mstate));
3477
3478 case DIF_VAR_UID:
3479 if (!dtrace_priv_proc(state, mstate))
3480 return (0);
3481
3482 /*
3483 * See comment in DIF_VAR_PID.
3484 */
3485 if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU))
3486 return ((uint64_t)p0.p_cred->cr_uid);
3487
3488 /*
3489 * It is always safe to dereference one's own t_procp pointer:
3490 * it always points to a valid, allocated proc structure.
3491 * (This is true because threads don't clean up their own
3492 * state -- they leave that task to whomever reaps them.)
3493 *
3494 * Additionally, it is safe to dereference one's own process
3495 * credential, since this is never NULL after process birth.
3496 */
3497 return ((uint64_t)curthread->t_procp->p_cred->cr_uid);
3498
3499 case DIF_VAR_GID:
3500 if (!dtrace_priv_proc(state, mstate))
3501 return (0);
3502
3503 /*
3504 * See comment in DIF_VAR_PID.
3505 */
3506 if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU))
3507 return ((uint64_t)p0.p_cred->cr_gid);
3508
3509 /*
3510 * It is always safe to dereference one's own t_procp pointer:
3511 * it always points to a valid, allocated proc structure.
3512 * (This is true because threads don't clean up their own
3513 * state -- they leave that task to whomever reaps them.)
3514 *
3515 * Additionally, it is safe to dereference one's own process
3516 * credential, since this is never NULL after process birth.
3517 */
3518 return ((uint64_t)curthread->t_procp->p_cred->cr_gid);
3519
3520 case DIF_VAR_ERRNO: {
3521 klwp_t *lwp;
3522 if (!dtrace_priv_proc(state, mstate))
3523 return (0);
3524
3525 /*
3526 * See comment in DIF_VAR_PID.
3527 */
3528 if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU))
3529 return (0);
3530
3531 /*
3532 * It is always safe to dereference one's own t_lwp pointer in
3533 * the event that this pointer is non-NULL. (This is true
3534 * because threads and lwps don't clean up their own state --
3535 * they leave that task to whomever reaps them.)
3536 */
3537 if ((lwp = curthread->t_lwp) == NULL)
3538 return (0);
3539
3540 return ((uint64_t)lwp->lwp_errno);
3541 }
3542 default:
3543 DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP);
3544 return (0);
3545 }
3546 }
3547
3548 static void
3549 dtrace_dif_variable_write(dtrace_mstate_t *mstate, dtrace_state_t *state,
3550 uint64_t v, uint64_t ndx, uint64_t data)
3551 {
3552 switch (v) {
3553 case DIF_VAR_UREGS: {
3554 klwp_t *lwp;
3555
3556 if (dtrace_destructive_disallow ||
3557 !dtrace_priv_proc_control(state, mstate)) {
3558 return;
3559 }
3560
3561 if ((lwp = curthread->t_lwp) == NULL) {
3562 DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR);
3563 cpu_core[CPU->cpu_id].cpuc_dtrace_illval = NULL;
3564 return;
3565 }
3566
3567 dtrace_setreg(lwp->lwp_regs, ndx, data);
3568 return;
3569 }
3570
3571 default:
3572 DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP);
3573 return;
3574 }
3575 }
3576
3577 typedef enum dtrace_json_state {
3578 DTRACE_JSON_REST = 1,
3579 DTRACE_JSON_OBJECT,
3580 DTRACE_JSON_STRING,
3581 DTRACE_JSON_STRING_ESCAPE,
3582 DTRACE_JSON_STRING_ESCAPE_UNICODE,
3583 DTRACE_JSON_COLON,
3584 DTRACE_JSON_COMMA,
3585 DTRACE_JSON_VALUE,
3586 DTRACE_JSON_IDENTIFIER,
3587 DTRACE_JSON_NUMBER,
3588 DTRACE_JSON_NUMBER_FRAC,
3589 DTRACE_JSON_NUMBER_EXP,
3590 DTRACE_JSON_COLLECT_OBJECT
3591 } dtrace_json_state_t;
3592
3593 /*
3594 * This function possesses just enough knowledge about JSON to extract a single
3595 * value from a JSON string and store it in the scratch buffer. It is able
3596 * to extract nested object values, and members of arrays by index.
3597 *
3598 * elemlist is a list of JSON keys, stored as packed NUL-terminated strings, to
3599 * be looked up as we descend into the object tree. e.g.
3600 *
3601 * foo[0].bar.baz[32] --> "foo" NUL "0" NUL "bar" NUL "baz" NUL "32" NUL
3602 * with nelems = 5.
3603 *
3604 * The run time of this function must be bounded above by strsize to limit the
3605 * amount of work done in probe context. As such, it is implemented as a
3606 * simple state machine, reading one character at a time using safe loads
3607 * until we find the requested element, hit a parsing error or run off the
3608 * end of the object or string.
3609 *
3610 * As there is no way for a subroutine to return an error without interrupting
3611 * clause execution, we simply return NULL in the event of a missing key or any
3612 * other error condition. Each NULL return in this function is commented with
3613 * the error condition it represents -- parsing or otherwise.
3614 *
3615 * The set of states for the state machine closely matches the JSON
3616 * specification (http://json.org/). Briefly:
3617 *
3618 * DTRACE_JSON_REST:
3619 * Skip whitespace until we find either a top-level Object, moving
3620 * to DTRACE_JSON_OBJECT; or an Array, moving to DTRACE_JSON_VALUE.
3621 *
3622 * DTRACE_JSON_OBJECT:
3623 * Locate the next key String in an Object. Sets a flag to denote
3624 * the next String as a key string and moves to DTRACE_JSON_STRING.
3625 *
3626 * DTRACE_JSON_COLON:
3627 * Skip whitespace until we find the colon that separates key Strings
3628 * from their values. Once found, move to DTRACE_JSON_VALUE.
3629 *
3630 * DTRACE_JSON_VALUE:
3631 * Detects the type of the next value (String, Number, Identifier, Object
3632 * or Array) and routes to the states that process that type. Here we also
3633 * deal with the element selector list if we are requested to traverse down
3634 * into the object tree.
3635 *
3636 * DTRACE_JSON_COMMA:
3637 * Skip whitespace until we find the comma that separates key-value pairs
3638 * in Objects (returning to DTRACE_JSON_OBJECT) or values in Arrays
3639 * (similarly DTRACE_JSON_VALUE). All following literal value processing
3640 * states return to this state at the end of their value, unless otherwise
3641 * noted.
3642 *
3643 * DTRACE_JSON_NUMBER, DTRACE_JSON_NUMBER_FRAC, DTRACE_JSON_NUMBER_EXP:
3644 * Processes a Number literal from the JSON, including any exponent
3645 * component that may be present. Numbers are returned as strings, which
3646 * may be passed to strtoll() if an integer is required.
3647 *
3648 * DTRACE_JSON_IDENTIFIER:
3649 * Processes a "true", "false" or "null" literal in the JSON.
3650 *
3651 * DTRACE_JSON_STRING, DTRACE_JSON_STRING_ESCAPE,
3652 * DTRACE_JSON_STRING_ESCAPE_UNICODE:
3653 * Processes a String literal from the JSON, whether the String denotes
3654 * a key, a value or part of a larger Object. Handles all escape sequences
3655 * present in the specification, including four-digit unicode characters,
3656 * but merely includes the escape sequence without converting it to the
3657 * actual escaped character. If the String is flagged as a key, we
3658 * move to DTRACE_JSON_COLON rather than DTRACE_JSON_COMMA.
3659 *
3660 * DTRACE_JSON_COLLECT_OBJECT:
3661 * This state collects an entire Object (or Array), correctly handling
3662 * embedded strings. If the full element selector list matches this nested
3663 * object, we return the Object in full as a string. If not, we use this
3664 * state to skip to the next value at this level and continue processing.
3665 *
3666 * NOTE: This function uses various macros from strtolctype.h to manipulate
3667 * digit values, etc -- these have all been checked to ensure they make
3668 * no additional function calls.
3669 */
3670 static char *
3671 dtrace_json(uint64_t size, uintptr_t json, char *elemlist, int nelems,
3672 char *dest)
3673 {
3674 dtrace_json_state_t state = DTRACE_JSON_REST;
3675 int64_t array_elem = INT64_MIN;
3676 int64_t array_pos = 0;
3677 uint8_t escape_unicount = 0;
3678 boolean_t string_is_key = B_FALSE;
3679 boolean_t collect_object = B_FALSE;
3680 boolean_t found_key = B_FALSE;
3681 boolean_t in_array = B_FALSE;
3682 uint32_t braces = 0, brackets = 0;
3683 char *elem = elemlist;
3684 char *dd = dest;
3685 uintptr_t cur;
3686
3687 for (cur = json; cur < json + size; cur++) {
3688 char cc = dtrace_load8(cur);
3689 if (cc == '\0')
3690 return (NULL);
3691
3692 switch (state) {
3693 case DTRACE_JSON_REST:
3694 if (isspace(cc))
3695 break;
3696
3697 if (cc == '{') {
3698 state = DTRACE_JSON_OBJECT;
3699 break;
3700 }
3701
3702 if (cc == '[') {
3703 in_array = B_TRUE;
3704 array_pos = 0;
3705 array_elem = dtrace_strtoll(elem, 10, size);
3706 found_key = array_elem == 0 ? B_TRUE : B_FALSE;
3707 state = DTRACE_JSON_VALUE;
3708 break;
3709 }
3710
3711 /*
3712 * ERROR: expected to find a top-level object or array.
3713 */
3714 return (NULL);
3715 case DTRACE_JSON_OBJECT:
3716 if (isspace(cc))
3717 break;
3718
3719 if (cc == '"') {
3720 state = DTRACE_JSON_STRING;
3721 string_is_key = B_TRUE;
3722 break;
3723 }
3724
3725 /*
3726 * ERROR: either the object did not start with a key
3727 * string, or we've run off the end of the object
3728 * without finding the requested key.
3729 */
3730 return (NULL);
3731 case DTRACE_JSON_STRING:
3732 if (cc == '\\') {
3733 *dd++ = '\\';
3734 state = DTRACE_JSON_STRING_ESCAPE;
3735 break;
3736 }
3737
3738 if (cc == '"') {
3739 if (collect_object) {
3740 /*
3741 * We don't reset the dest here, as
3742 * the string is part of a larger
3743 * object being collected.
3744 */
3745 *dd++ = cc;
3746 collect_object = B_FALSE;
3747 state = DTRACE_JSON_COLLECT_OBJECT;
3748 break;
3749 }
3750 *dd = '\0';
3751 dd = dest; /* reset string buffer */
3752 if (string_is_key) {
3753 if (dtrace_strncmp(dest, elem,
3754 size) == 0)
3755 found_key = B_TRUE;
3756 } else if (found_key) {
3757 if (nelems > 1) {
3758 /*
3759 * We expected an object, not
3760 * this string.
3761 */
3762 return (NULL);
3763 }
3764 return (dest);
3765 }
3766 state = string_is_key ? DTRACE_JSON_COLON :
3767 DTRACE_JSON_COMMA;
3768 string_is_key = B_FALSE;
3769 break;
3770 }
3771
3772 *dd++ = cc;
3773 break;
3774 case DTRACE_JSON_STRING_ESCAPE:
3775 *dd++ = cc;
3776 if (cc == 'u') {
3777 escape_unicount = 0;
3778 state = DTRACE_JSON_STRING_ESCAPE_UNICODE;
3779 } else {
3780 state = DTRACE_JSON_STRING;
3781 }
3782 break;
3783 case DTRACE_JSON_STRING_ESCAPE_UNICODE:
3784 if (!isxdigit(cc)) {
3785 /*
3786 * ERROR: invalid unicode escape, expected
3787 * four valid hexidecimal digits.
3788 */
3789 return (NULL);
3790 }
3791
3792 *dd++ = cc;
3793 if (++escape_unicount == 4)
3794 state = DTRACE_JSON_STRING;
3795 break;
3796 case DTRACE_JSON_COLON:
3797 if (isspace(cc))
3798 break;
3799
3800 if (cc == ':') {
3801 state = DTRACE_JSON_VALUE;
3802 break;
3803 }
3804
3805 /*
3806 * ERROR: expected a colon.
3807 */
3808 return (NULL);
3809 case DTRACE_JSON_COMMA:
3810 if (isspace(cc))
3811 break;
3812
3813 if (cc == ',') {
3814 if (in_array) {
3815 state = DTRACE_JSON_VALUE;
3816 if (++array_pos == array_elem)
3817 found_key = B_TRUE;
3818 } else {
3819 state = DTRACE_JSON_OBJECT;
3820 }
3821 break;
3822 }
3823
3824 /*
3825 * ERROR: either we hit an unexpected character, or
3826 * we reached the end of the object or array without
3827 * finding the requested key.
3828 */
3829 return (NULL);
3830 case DTRACE_JSON_IDENTIFIER:
3831 if (islower(cc)) {
3832 *dd++ = cc;
3833 break;
3834 }
3835
3836 *dd = '\0';
3837 dd = dest; /* reset string buffer */
3838
3839 if (dtrace_strncmp(dest, "true", 5) == 0 ||
3840 dtrace_strncmp(dest, "false", 6) == 0 ||
3841 dtrace_strncmp(dest, "null", 5) == 0) {
3842 if (found_key) {
3843 if (nelems > 1) {
3844 /*
3845 * ERROR: We expected an object,
3846 * not this identifier.
3847 */
3848 return (NULL);
3849 }
3850 return (dest);
3851 } else {
3852 cur--;
3853 state = DTRACE_JSON_COMMA;
3854 break;
3855 }
3856 }
3857
3858 /*
3859 * ERROR: we did not recognise the identifier as one
3860 * of those in the JSON specification.
3861 */
3862 return (NULL);
3863 case DTRACE_JSON_NUMBER:
3864 if (cc == '.') {
3865 *dd++ = cc;
3866 state = DTRACE_JSON_NUMBER_FRAC;
3867 break;
3868 }
3869
3870 if (cc == 'x' || cc == 'X') {
3871 /*
3872 * ERROR: specification explicitly excludes
3873 * hexidecimal or octal numbers.
3874 */
3875 return (NULL);
3876 }
3877
3878 /* FALLTHRU */
3879 case DTRACE_JSON_NUMBER_FRAC:
3880 if (cc == 'e' || cc == 'E') {
3881 *dd++ = cc;
3882 state = DTRACE_JSON_NUMBER_EXP;
3883 break;
3884 }
3885
3886 if (cc == '+' || cc == '-') {
3887 /*
3888 * ERROR: expect sign as part of exponent only.
3889 */
3890 return (NULL);
3891 }
3892 /* FALLTHRU */
3893 case DTRACE_JSON_NUMBER_EXP:
3894 if (isdigit(cc) || cc == '+' || cc == '-') {
3895 *dd++ = cc;
3896 break;
3897 }
3898
3899 *dd = '\0';
3900 dd = dest; /* reset string buffer */
3901 if (found_key) {
3902 if (nelems > 1) {
3903 /*
3904 * ERROR: We expected an object, not
3905 * this number.
3906 */
3907 return (NULL);
3908 }
3909 return (dest);
3910 }
3911
3912 cur--;
3913 state = DTRACE_JSON_COMMA;
3914 break;
3915 case DTRACE_JSON_VALUE:
3916 if (isspace(cc))
3917 break;
3918
3919 if (cc == '{' || cc == '[') {
3920 if (nelems > 1 && found_key) {
3921 in_array = cc == '[' ? B_TRUE : B_FALSE;
3922 /*
3923 * If our element selector directs us
3924 * to descend into this nested object,
3925 * then move to the next selector
3926 * element in the list and restart the
3927 * state machine.
3928 */
3929 while (*elem != '\0')
3930 elem++;
3931 elem++; /* skip the inter-element NUL */
3932 nelems--;
3933 dd = dest;
3934 if (in_array) {
3935 state = DTRACE_JSON_VALUE;
3936 array_pos = 0;
3937 array_elem = dtrace_strtoll(
3938 elem, 10, size);
3939 found_key = array_elem == 0 ?
3940 B_TRUE : B_FALSE;
3941 } else {
3942 found_key = B_FALSE;
3943 state = DTRACE_JSON_OBJECT;
3944 }
3945 break;
3946 }
3947
3948 /*
3949 * Otherwise, we wish to either skip this
3950 * nested object or return it in full.
3951 */
3952 if (cc == '[')
3953 brackets = 1;
3954 else
3955 braces = 1;
3956 *dd++ = cc;
3957 state = DTRACE_JSON_COLLECT_OBJECT;
3958 break;
3959 }
3960
3961 if (cc == '"') {
3962 state = DTRACE_JSON_STRING;
3963 break;
3964 }
3965
3966 if (islower(cc)) {
3967 /*
3968 * Here we deal with true, false and null.
3969 */
3970 *dd++ = cc;
3971 state = DTRACE_JSON_IDENTIFIER;
3972 break;
3973 }
3974
3975 if (cc == '-' || isdigit(cc)) {
3976 *dd++ = cc;
3977 state = DTRACE_JSON_NUMBER;
3978 break;
3979 }
3980
3981 /*
3982 * ERROR: unexpected character at start of value.
3983 */
3984 return (NULL);
3985 case DTRACE_JSON_COLLECT_OBJECT:
3986 if (cc == '\0')
3987 /*
3988 * ERROR: unexpected end of input.
3989 */
3990 return (NULL);
3991
3992 *dd++ = cc;
3993 if (cc == '"') {
3994 collect_object = B_TRUE;
3995 state = DTRACE_JSON_STRING;
3996 break;
3997 }
3998
3999 if (cc == ']') {
4000 if (brackets-- == 0) {
4001 /*
4002 * ERROR: unbalanced brackets.
4003 */
4004 return (NULL);
4005 }
4006 } else if (cc == '}') {
4007 if (braces-- == 0) {
4008 /*
4009 * ERROR: unbalanced braces.
4010 */
4011 return (NULL);
4012 }
4013 } else if (cc == '{') {
4014 braces++;
4015 } else if (cc == '[') {
4016 brackets++;
4017 }
4018
4019 if (brackets == 0 && braces == 0) {
4020 if (found_key) {
4021 *dd = '\0';
4022 return (dest);
4023 }
4024 dd = dest; /* reset string buffer */
4025 state = DTRACE_JSON_COMMA;
4026 }
4027 break;
4028 }
4029 }
4030 return (NULL);
4031 }
4032
4033 /*
4034 * Emulate the execution of DTrace ID subroutines invoked by the call opcode.
4035 * Notice that we don't bother validating the proper number of arguments or
4036 * their types in the tuple stack. This isn't needed because all argument
4037 * interpretation is safe because of our load safety -- the worst that can
4038 * happen is that a bogus program can obtain bogus results.
4039 */
4040 static void
4041 dtrace_dif_subr(uint_t subr, uint_t rd, uint64_t *regs,
4042 dtrace_key_t *tupregs, int nargs,
4043 dtrace_mstate_t *mstate, dtrace_state_t *state)
4044 {
4045 volatile uint16_t *flags = &cpu_core[CPU->cpu_id].cpuc_dtrace_flags;
4046 volatile uintptr_t *illval = &cpu_core[CPU->cpu_id].cpuc_dtrace_illval;
4047 dtrace_vstate_t *vstate = &state->dts_vstate;
4048
4049 union {
4050 mutex_impl_t mi;
4051 uint64_t mx;
4052 } m;
4053
4054 union {
4055 krwlock_t ri;
4056 uintptr_t rw;
4057 } r;
4058
4059 switch (subr) {
4060 case DIF_SUBR_RAND:
4061 regs[rd] = (dtrace_gethrtime() * 2416 + 374441) % 1771875;
4062 break;
4063
4064 case DIF_SUBR_MUTEX_OWNED:
4065 if (!dtrace_canload(tupregs[0].dttk_value, sizeof (kmutex_t),
4066 mstate, vstate)) {
4067 regs[rd] = NULL;
4068 break;
4069 }
4070
4071 m.mx = dtrace_load64(tupregs[0].dttk_value);
4072 if (MUTEX_TYPE_ADAPTIVE(&m.mi))
4073 regs[rd] = MUTEX_OWNER(&m.mi) != MUTEX_NO_OWNER;
4074 else
4075 regs[rd] = LOCK_HELD(&m.mi.m_spin.m_spinlock);
4076 break;
4077
4078 case DIF_SUBR_MUTEX_OWNER:
4079 if (!dtrace_canload(tupregs[0].dttk_value, sizeof (kmutex_t),
4080 mstate, vstate)) {
4081 regs[rd] = NULL;
4082 break;
4083 }
4084
4085 m.mx = dtrace_load64(tupregs[0].dttk_value);
4086 if (MUTEX_TYPE_ADAPTIVE(&m.mi) &&
4087 MUTEX_OWNER(&m.mi) != MUTEX_NO_OWNER)
4088 regs[rd] = (uintptr_t)MUTEX_OWNER(&m.mi);
4089 else
4090 regs[rd] = 0;
4091 break;
4092
4093 case DIF_SUBR_MUTEX_TYPE_ADAPTIVE:
4094 if (!dtrace_canload(tupregs[0].dttk_value, sizeof (kmutex_t),
4095 mstate, vstate)) {
4096 regs[rd] = NULL;
4097 break;
4098 }
4099
4100 m.mx = dtrace_load64(tupregs[0].dttk_value);
4101 regs[rd] = MUTEX_TYPE_ADAPTIVE(&m.mi);
4102 break;
4103
4104 case DIF_SUBR_MUTEX_TYPE_SPIN:
4105 if (!dtrace_canload(tupregs[0].dttk_value, sizeof (kmutex_t),
4106 mstate, vstate)) {
4107 regs[rd] = NULL;
4108 break;
4109 }
4110
4111 m.mx = dtrace_load64(tupregs[0].dttk_value);
4112 regs[rd] = MUTEX_TYPE_SPIN(&m.mi);
4113 break;
4114
4115 case DIF_SUBR_RW_READ_HELD: {
4116 uintptr_t tmp;
4117
4118 if (!dtrace_canload(tupregs[0].dttk_value, sizeof (uintptr_t),
4119 mstate, vstate)) {
4120 regs[rd] = NULL;
4121 break;
4122 }
4123
4124 r.rw = dtrace_loadptr(tupregs[0].dttk_value);
4125 regs[rd] = _RW_READ_HELD(&r.ri, tmp);
4126 break;
4127 }
4128
4129 case DIF_SUBR_RW_WRITE_HELD:
4130 if (!dtrace_canload(tupregs[0].dttk_value, sizeof (krwlock_t),
4131 mstate, vstate)) {
4132 regs[rd] = NULL;
4133 break;
4134 }
4135
4136 r.rw = dtrace_loadptr(tupregs[0].dttk_value);
4137 regs[rd] = _RW_WRITE_HELD(&r.ri);
4138 break;
4139
4140 case DIF_SUBR_RW_ISWRITER:
4141 if (!dtrace_canload(tupregs[0].dttk_value, sizeof (krwlock_t),
4142 mstate, vstate)) {
4143 regs[rd] = NULL;
4144 break;
4145 }
4146
4147 r.rw = dtrace_loadptr(tupregs[0].dttk_value);
4148 regs[rd] = _RW_ISWRITER(&r.ri);
4149 break;
4150
4151 case DIF_SUBR_BCOPY: {
4152 /*
4153 * We need to be sure that the destination is in the scratch
4154 * region -- no other region is allowed.
4155 */
4156 uintptr_t src = tupregs[0].dttk_value;
4157 uintptr_t dest = tupregs[1].dttk_value;
4158 size_t size = tupregs[2].dttk_value;
4159
4160 if (!dtrace_inscratch(dest, size, mstate)) {
4161 *flags |= CPU_DTRACE_BADADDR;
4162 *illval = regs[rd];
4163 break;
4164 }
4165
4166 if (!dtrace_canload(src, size, mstate, vstate)) {
4167 regs[rd] = NULL;
4168 break;
4169 }
4170
4171 dtrace_bcopy((void *)src, (void *)dest, size);
4172 break;
4173 }
4174
4175 case DIF_SUBR_ALLOCA:
4176 case DIF_SUBR_COPYIN: {
4177 uintptr_t dest = P2ROUNDUP(mstate->dtms_scratch_ptr, 8);
4178 uint64_t size =
4179 tupregs[subr == DIF_SUBR_ALLOCA ? 0 : 1].dttk_value;
4180 size_t scratch_size = (dest - mstate->dtms_scratch_ptr) + size;
4181
4182 /*
4183 * This action doesn't require any credential checks since
4184 * probes will not activate in user contexts to which the
4185 * enabling user does not have permissions.
4186 */
4187
4188 /*
4189 * Rounding up the user allocation size could have overflowed
4190 * a large, bogus allocation (like -1ULL) to 0.
4191 */
4192 if (scratch_size < size ||
4193 !DTRACE_INSCRATCH(mstate, scratch_size)) {
4194 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
4195 regs[rd] = NULL;
4196 break;
4197 }
4198
4199 if (subr == DIF_SUBR_COPYIN) {
4200 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
4201 dtrace_copyin(tupregs[0].dttk_value, dest, size, flags);
4202 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
4203 }
4204
4205 mstate->dtms_scratch_ptr += scratch_size;
4206 regs[rd] = dest;
4207 break;
4208 }
4209
4210 case DIF_SUBR_COPYINTO: {
4211 uint64_t size = tupregs[1].dttk_value;
4212 uintptr_t dest = tupregs[2].dttk_value;
4213
4214 /*
4215 * This action doesn't require any credential checks since
4216 * probes will not activate in user contexts to which the
4217 * enabling user does not have permissions.
4218 */
4219 if (!dtrace_inscratch(dest, size, mstate)) {
4220 *flags |= CPU_DTRACE_BADADDR;
4221 *illval = regs[rd];
4222 break;
4223 }
4224
4225 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
4226 dtrace_copyin(tupregs[0].dttk_value, dest, size, flags);
4227 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
4228 break;
4229 }
4230
4231 case DIF_SUBR_COPYINSTR: {
4232 uintptr_t dest = mstate->dtms_scratch_ptr;
4233 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
4234
4235 if (nargs > 1 && tupregs[1].dttk_value < size)
4236 size = tupregs[1].dttk_value + 1;
4237
4238 /*
4239 * This action doesn't require any credential checks since
4240 * probes will not activate in user contexts to which the
4241 * enabling user does not have permissions.
4242 */
4243 if (!DTRACE_INSCRATCH(mstate, size)) {
4244 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
4245 regs[rd] = NULL;
4246 break;
4247 }
4248
4249 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
4250 dtrace_copyinstr(tupregs[0].dttk_value, dest, size, flags);
4251 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
4252
4253 ((char *)dest)[size - 1] = '\0';
4254 mstate->dtms_scratch_ptr += size;
4255 regs[rd] = dest;
4256 break;
4257 }
4258
4259 case DIF_SUBR_MSGSIZE:
4260 case DIF_SUBR_MSGDSIZE: {
4261 uintptr_t baddr = tupregs[0].dttk_value, daddr;
4262 uintptr_t wptr, rptr;
4263 size_t count = 0;
4264 int cont = 0;
4265
4266 while (baddr != NULL && !(*flags & CPU_DTRACE_FAULT)) {
4267
4268 if (!dtrace_canload(baddr, sizeof (mblk_t), mstate,
4269 vstate)) {
4270 regs[rd] = NULL;
4271 break;
4272 }
4273
4274 wptr = dtrace_loadptr(baddr +
4275 offsetof(mblk_t, b_wptr));
4276
4277 rptr = dtrace_loadptr(baddr +
4278 offsetof(mblk_t, b_rptr));
4279
4280 if (wptr < rptr) {
4281 *flags |= CPU_DTRACE_BADADDR;
4282 *illval = tupregs[0].dttk_value;
4283 break;
4284 }
4285
4286 daddr = dtrace_loadptr(baddr +
4287 offsetof(mblk_t, b_datap));
4288
4289 baddr = dtrace_loadptr(baddr +
4290 offsetof(mblk_t, b_cont));
4291
4292 /*
4293 * We want to prevent against denial-of-service here,
4294 * so we're only going to search the list for
4295 * dtrace_msgdsize_max mblks.
4296 */
4297 if (cont++ > dtrace_msgdsize_max) {
4298 *flags |= CPU_DTRACE_ILLOP;
4299 break;
4300 }
4301
4302 if (subr == DIF_SUBR_MSGDSIZE) {
4303 if (dtrace_load8(daddr +
4304 offsetof(dblk_t, db_type)) != M_DATA)
4305 continue;
4306 }
4307
4308 count += wptr - rptr;
4309 }
4310
4311 if (!(*flags & CPU_DTRACE_FAULT))
4312 regs[rd] = count;
4313
4314 break;
4315 }
4316
4317 case DIF_SUBR_PROGENYOF: {
4318 pid_t pid = tupregs[0].dttk_value;
4319 proc_t *p;
4320 int rval = 0;
4321
4322 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
4323
4324 for (p = curthread->t_procp; p != NULL; p = p->p_parent) {
4325 if (p->p_pidp->pid_id == pid) {
4326 rval = 1;
4327 break;
4328 }
4329 }
4330
4331 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
4332
4333 regs[rd] = rval;
4334 break;
4335 }
4336
4337 case DIF_SUBR_SPECULATION:
4338 regs[rd] = dtrace_speculation(state);
4339 break;
4340
4341 case DIF_SUBR_COPYOUT: {
4342 uintptr_t kaddr = tupregs[0].dttk_value;
4343 uintptr_t uaddr = tupregs[1].dttk_value;
4344 uint64_t size = tupregs[2].dttk_value;
4345
4346 if (!dtrace_destructive_disallow &&
4347 dtrace_priv_proc_control(state, mstate) &&
4348 !dtrace_istoxic(kaddr, size) &&
4349 dtrace_canload(kaddr, size, mstate, vstate)) {
4350 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
4351 dtrace_copyout(kaddr, uaddr, size, flags);
4352 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
4353 }
4354 break;
4355 }
4356
4357 case DIF_SUBR_COPYOUTSTR: {
4358 uintptr_t kaddr = tupregs[0].dttk_value;
4359 uintptr_t uaddr = tupregs[1].dttk_value;
4360 uint64_t size = tupregs[2].dttk_value;
4361 size_t lim;
4362
4363 if (!dtrace_destructive_disallow &&
4364 dtrace_priv_proc_control(state, mstate) &&
4365 !dtrace_istoxic(kaddr, size) &&
4366 dtrace_strcanload(kaddr, size, &lim, mstate, vstate)) {
4367 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
4368 dtrace_copyoutstr(kaddr, uaddr, lim, flags);
4369 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
4370 }
4371 break;
4372 }
4373
4374 case DIF_SUBR_STRLEN: {
4375 size_t size = state->dts_options[DTRACEOPT_STRSIZE];
4376 uintptr_t addr = (uintptr_t)tupregs[0].dttk_value;
4377 size_t lim;
4378
4379 if (!dtrace_strcanload(addr, size, &lim, mstate, vstate)) {
4380 regs[rd] = NULL;
4381 break;
4382 }
4383 regs[rd] = dtrace_strlen((char *)addr, lim);
4384
4385 break;
4386 }
4387
4388 case DIF_SUBR_STRCHR:
4389 case DIF_SUBR_STRRCHR: {
4390 /*
4391 * We're going to iterate over the string looking for the
4392 * specified character. We will iterate until we have reached
4393 * the string length or we have found the character. If this
4394 * is DIF_SUBR_STRRCHR, we will look for the last occurrence
4395 * of the specified character instead of the first.
4396 */
4397 uintptr_t addr = tupregs[0].dttk_value;
4398 uintptr_t addr_limit;
4399 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
4400 size_t lim;
4401 char c, target = (char)tupregs[1].dttk_value;
4402
4403 if (!dtrace_strcanload(addr, size, &lim, mstate, vstate)) {
4404 regs[rd] = NULL;
4405 break;
4406 }
4407 addr_limit = addr + lim;
4408
4409 for (regs[rd] = NULL; addr < addr_limit; addr++) {
4410 if ((c = dtrace_load8(addr)) == target) {
4411 regs[rd] = addr;
4412
4413 if (subr == DIF_SUBR_STRCHR)
4414 break;
4415 }
4416 if (c == '\0')
4417 break;
4418 }
4419
4420 break;
4421 }
4422
4423 case DIF_SUBR_STRSTR:
4424 case DIF_SUBR_INDEX:
4425 case DIF_SUBR_RINDEX: {
4426 /*
4427 * We're going to iterate over the string looking for the
4428 * specified string. We will iterate until we have reached
4429 * the string length or we have found the string. (Yes, this
4430 * is done in the most naive way possible -- but considering
4431 * that the string we're searching for is likely to be
4432 * relatively short, the complexity of Rabin-Karp or similar
4433 * hardly seems merited.)
4434 */
4435 char *addr = (char *)(uintptr_t)tupregs[0].dttk_value;
4436 char *substr = (char *)(uintptr_t)tupregs[1].dttk_value;
4437 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
4438 size_t len = dtrace_strlen(addr, size);
4439 size_t sublen = dtrace_strlen(substr, size);
4440 char *limit = addr + len, *orig = addr;
4441 int notfound = subr == DIF_SUBR_STRSTR ? 0 : -1;
4442 int inc = 1;
4443
4444 regs[rd] = notfound;
4445
4446 if (!dtrace_canload((uintptr_t)addr, len + 1, mstate, vstate)) {
4447 regs[rd] = NULL;
4448 break;
4449 }
4450
4451 if (!dtrace_canload((uintptr_t)substr, sublen + 1, mstate,
4452 vstate)) {
4453 regs[rd] = NULL;
4454 break;
4455 }
4456
4457 /*
4458 * strstr() and index()/rindex() have similar semantics if
4459 * both strings are the empty string: strstr() returns a
4460 * pointer to the (empty) string, and index() and rindex()
4461 * both return index 0 (regardless of any position argument).
4462 */
4463 if (sublen == 0 && len == 0) {
4464 if (subr == DIF_SUBR_STRSTR)
4465 regs[rd] = (uintptr_t)addr;
4466 else
4467 regs[rd] = 0;
4468 break;
4469 }
4470
4471 if (subr != DIF_SUBR_STRSTR) {
4472 if (subr == DIF_SUBR_RINDEX) {
4473 limit = orig - 1;
4474 addr += len;
4475 inc = -1;
4476 }
4477
4478 /*
4479 * Both index() and rindex() take an optional position
4480 * argument that denotes the starting position.
4481 */
4482 if (nargs == 3) {
4483 int64_t pos = (int64_t)tupregs[2].dttk_value;
4484
4485 /*
4486 * If the position argument to index() is
4487 * negative, Perl implicitly clamps it at
4488 * zero. This semantic is a little surprising
4489 * given the special meaning of negative
4490 * positions to similar Perl functions like
4491 * substr(), but it appears to reflect a
4492 * notion that index() can start from a
4493 * negative index and increment its way up to
4494 * the string. Given this notion, Perl's
4495 * rindex() is at least self-consistent in
4496 * that it implicitly clamps positions greater
4497 * than the string length to be the string
4498 * length. Where Perl completely loses
4499 * coherence, however, is when the specified
4500 * substring is the empty string (""). In
4501 * this case, even if the position is
4502 * negative, rindex() returns 0 -- and even if
4503 * the position is greater than the length,
4504 * index() returns the string length. These
4505 * semantics violate the notion that index()
4506 * should never return a value less than the
4507 * specified position and that rindex() should
4508 * never return a value greater than the
4509 * specified position. (One assumes that
4510 * these semantics are artifacts of Perl's
4511 * implementation and not the results of
4512 * deliberate design -- it beggars belief that
4513 * even Larry Wall could desire such oddness.)
4514 * While in the abstract one would wish for
4515 * consistent position semantics across
4516 * substr(), index() and rindex() -- or at the
4517 * very least self-consistent position
4518 * semantics for index() and rindex() -- we
4519 * instead opt to keep with the extant Perl
4520 * semantics, in all their broken glory. (Do
4521 * we have more desire to maintain Perl's
4522 * semantics than Perl does? Probably.)
4523 */
4524 if (subr == DIF_SUBR_RINDEX) {
4525 if (pos < 0) {
4526 if (sublen == 0)
4527 regs[rd] = 0;
4528 break;
4529 }
4530
4531 if (pos > len)
4532 pos = len;
4533 } else {
4534 if (pos < 0)
4535 pos = 0;
4536
4537 if (pos >= len) {
4538 if (sublen == 0)
4539 regs[rd] = len;
4540 break;
4541 }
4542 }
4543
4544 addr = orig + pos;
4545 }
4546 }
4547
4548 for (regs[rd] = notfound; addr != limit; addr += inc) {
4549 if (dtrace_strncmp(addr, substr, sublen) == 0) {
4550 if (subr != DIF_SUBR_STRSTR) {
4551 /*
4552 * As D index() and rindex() are
4553 * modeled on Perl (and not on awk),
4554 * we return a zero-based (and not a
4555 * one-based) index. (For you Perl
4556 * weenies: no, we're not going to add
4557 * $[ -- and shouldn't you be at a con
4558 * or something?)
4559 */
4560 regs[rd] = (uintptr_t)(addr - orig);
4561 break;
4562 }
4563
4564 ASSERT(subr == DIF_SUBR_STRSTR);
4565 regs[rd] = (uintptr_t)addr;
4566 break;
4567 }
4568 }
4569
4570 break;
4571 }
4572
4573 case DIF_SUBR_STRTOK: {
4574 uintptr_t addr = tupregs[0].dttk_value;
4575 uintptr_t tokaddr = tupregs[1].dttk_value;
4576 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
4577 uintptr_t limit, toklimit;
4578 size_t clim;
4579 uint8_t c, tokmap[32]; /* 256 / 8 */
4580 char *dest = (char *)mstate->dtms_scratch_ptr;
4581 int i;
4582
4583 /*
4584 * Check both the token buffer and (later) the input buffer,
4585 * since both could be non-scratch addresses.
4586 */
4587 if (!dtrace_strcanload(tokaddr, size, &clim, mstate, vstate)) {
4588 regs[rd] = NULL;
4589 break;
4590 }
4591 toklimit = tokaddr + clim;
4592
4593 if (!DTRACE_INSCRATCH(mstate, size)) {
4594 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
4595 regs[rd] = NULL;
4596 break;
4597 }
4598
4599 if (addr == NULL) {
4600 /*
4601 * If the address specified is NULL, we use our saved
4602 * strtok pointer from the mstate. Note that this
4603 * means that the saved strtok pointer is _only_
4604 * valid within multiple enablings of the same probe --
4605 * it behaves like an implicit clause-local variable.
4606 */
4607 addr = mstate->dtms_strtok;
4608 limit = mstate->dtms_strtok_limit;
4609 } else {
4610 /*
4611 * If the user-specified address is non-NULL we must
4612 * access check it. This is the only time we have
4613 * a chance to do so, since this address may reside
4614 * in the string table of this clause-- future calls
4615 * (when we fetch addr from mstate->dtms_strtok)
4616 * would fail this access check.
4617 */
4618 if (!dtrace_strcanload(addr, size, &clim, mstate,
4619 vstate)) {
4620 regs[rd] = NULL;
4621 break;
4622 }
4623 limit = addr + clim;
4624 }
4625
4626 /*
4627 * First, zero the token map, and then process the token
4628 * string -- setting a bit in the map for every character
4629 * found in the token string.
4630 */
4631 for (i = 0; i < sizeof (tokmap); i++)
4632 tokmap[i] = 0;
4633
4634 for (; tokaddr < toklimit; tokaddr++) {
4635 if ((c = dtrace_load8(tokaddr)) == '\0')
4636 break;
4637
4638 ASSERT((c >> 3) < sizeof (tokmap));
4639 tokmap[c >> 3] |= (1 << (c & 0x7));
4640 }
4641
4642 for (; addr < limit; addr++) {
4643 /*
4644 * We're looking for a character that is _not_
4645 * contained in the token string.
4646 */
4647 if ((c = dtrace_load8(addr)) == '\0')
4648 break;
4649
4650 if (!(tokmap[c >> 3] & (1 << (c & 0x7))))
4651 break;
4652 }
4653
4654 if (c == '\0') {
4655 /*
4656 * We reached the end of the string without finding
4657 * any character that was not in the token string.
4658 * We return NULL in this case, and we set the saved
4659 * address to NULL as well.
4660 */
4661 regs[rd] = NULL;
4662 mstate->dtms_strtok = NULL;
4663 mstate->dtms_strtok_limit = NULL;
4664 break;
4665 }
4666
4667 /*
4668 * From here on, we're copying into the destination string.
4669 */
4670 for (i = 0; addr < limit && i < size - 1; addr++) {
4671 if ((c = dtrace_load8(addr)) == '\0')
4672 break;
4673
4674 if (tokmap[c >> 3] & (1 << (c & 0x7)))
4675 break;
4676
4677 ASSERT(i < size);
4678 dest[i++] = c;
4679 }
4680
4681 ASSERT(i < size);
4682 dest[i] = '\0';
4683 regs[rd] = (uintptr_t)dest;
4684 mstate->dtms_scratch_ptr += size;
4685 mstate->dtms_strtok = addr;
4686 mstate->dtms_strtok_limit = limit;
4687 break;
4688 }
4689
4690 case DIF_SUBR_SUBSTR: {
4691 uintptr_t s = tupregs[0].dttk_value;
4692 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
4693 char *d = (char *)mstate->dtms_scratch_ptr;
4694 int64_t index = (int64_t)tupregs[1].dttk_value;
4695 int64_t remaining = (int64_t)tupregs[2].dttk_value;
4696 size_t len = dtrace_strlen((char *)s, size);
4697 int64_t i;
4698
4699 if (!dtrace_canload(s, len + 1, mstate, vstate)) {
4700 regs[rd] = NULL;
4701 break;
4702 }
4703
4704 if (!DTRACE_INSCRATCH(mstate, size)) {
4705 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
4706 regs[rd] = NULL;
4707 break;
4708 }
4709
4710 if (nargs <= 2)
4711 remaining = (int64_t)size;
4712
4713 if (index < 0) {
4714 index += len;
4715
4716 if (index < 0 && index + remaining > 0) {
4717 remaining += index;
4718 index = 0;
4719 }
4720 }
4721
4722 if (index >= len || index < 0) {
4723 remaining = 0;
4724 } else if (remaining < 0) {
4725 remaining += len - index;
4726 } else if (index + remaining > size) {
4727 remaining = size - index;
4728 }
4729
4730 for (i = 0; i < remaining; i++) {
4731 if ((d[i] = dtrace_load8(s + index + i)) == '\0')
4732 break;
4733 }
4734
4735 d[i] = '\0';
4736
4737 mstate->dtms_scratch_ptr += size;
4738 regs[rd] = (uintptr_t)d;
4739 break;
4740 }
4741
4742 case DIF_SUBR_JSON: {
4743 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
4744 uintptr_t json = tupregs[0].dttk_value;
4745 size_t jsonlen = dtrace_strlen((char *)json, size);
4746 uintptr_t elem = tupregs[1].dttk_value;
4747 size_t elemlen = dtrace_strlen((char *)elem, size);
4748
4749 char *dest = (char *)mstate->dtms_scratch_ptr;
4750 char *elemlist = (char *)mstate->dtms_scratch_ptr + jsonlen + 1;
4751 char *ee = elemlist;
4752 int nelems = 1;
4753 uintptr_t cur;
4754
4755 if (!dtrace_canload(json, jsonlen + 1, mstate, vstate) ||
4756 !dtrace_canload(elem, elemlen + 1, mstate, vstate)) {
4757 regs[rd] = NULL;
4758 break;
4759 }
4760
4761 if (!DTRACE_INSCRATCH(mstate, jsonlen + 1 + elemlen + 1)) {
4762 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
4763 regs[rd] = NULL;
4764 break;
4765 }
4766
4767 /*
4768 * Read the element selector and split it up into a packed list
4769 * of strings.
4770 */
4771 for (cur = elem; cur < elem + elemlen; cur++) {
4772 char cc = dtrace_load8(cur);
4773
4774 if (cur == elem && cc == '[') {
4775 /*
4776 * If the first element selector key is
4777 * actually an array index then ignore the
4778 * bracket.
4779 */
4780 continue;
4781 }
4782
4783 if (cc == ']')
4784 continue;
4785
4786 if (cc == '.' || cc == '[') {
4787 nelems++;
4788 cc = '\0';
4789 }
4790
4791 *ee++ = cc;
4792 }
4793 *ee++ = '\0';
4794
4795 if ((regs[rd] = (uintptr_t)dtrace_json(size, json, elemlist,
4796 nelems, dest)) != NULL)
4797 mstate->dtms_scratch_ptr += jsonlen + 1;
4798 break;
4799 }
4800
4801 case DIF_SUBR_TOUPPER:
4802 case DIF_SUBR_TOLOWER: {
4803 uintptr_t s = tupregs[0].dttk_value;
4804 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
4805 char *dest = (char *)mstate->dtms_scratch_ptr, c;
4806 size_t len = dtrace_strlen((char *)s, size);
4807 char lower, upper, convert;
4808 int64_t i;
4809
4810 if (subr == DIF_SUBR_TOUPPER) {
4811 lower = 'a';
4812 upper = 'z';
4813 convert = 'A';
4814 } else {
4815 lower = 'A';
4816 upper = 'Z';
4817 convert = 'a';
4818 }
4819
4820 if (!dtrace_canload(s, len + 1, mstate, vstate)) {
4821 regs[rd] = NULL;
4822 break;
4823 }
4824
4825 if (!DTRACE_INSCRATCH(mstate, size)) {
4826 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
4827 regs[rd] = NULL;
4828 break;
4829 }
4830
4831 for (i = 0; i < size - 1; i++) {
4832 if ((c = dtrace_load8(s + i)) == '\0')
4833 break;
4834
4835 if (c >= lower && c <= upper)
4836 c = convert + (c - lower);
4837
4838 dest[i] = c;
4839 }
4840
4841 ASSERT(i < size);
4842 dest[i] = '\0';
4843 regs[rd] = (uintptr_t)dest;
4844 mstate->dtms_scratch_ptr += size;
4845 break;
4846 }
4847
4848 case DIF_SUBR_GETMAJOR:
4849 #ifdef _LP64
4850 regs[rd] = (tupregs[0].dttk_value >> NBITSMINOR64) & MAXMAJ64;
4851 #else
4852 regs[rd] = (tupregs[0].dttk_value >> NBITSMINOR) & MAXMAJ;
4853 #endif
4854 break;
4855
4856 case DIF_SUBR_GETMINOR:
4857 #ifdef _LP64
4858 regs[rd] = tupregs[0].dttk_value & MAXMIN64;
4859 #else
4860 regs[rd] = tupregs[0].dttk_value & MAXMIN;
4861 #endif
4862 break;
4863
4864 case DIF_SUBR_DDI_PATHNAME: {
4865 /*
4866 * This one is a galactic mess. We are going to roughly
4867 * emulate ddi_pathname(), but it's made more complicated
4868 * by the fact that we (a) want to include the minor name and
4869 * (b) must proceed iteratively instead of recursively.
4870 */
4871 uintptr_t dest = mstate->dtms_scratch_ptr;
4872 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
4873 char *start = (char *)dest, *end = start + size - 1;
4874 uintptr_t daddr = tupregs[0].dttk_value;
4875 int64_t minor = (int64_t)tupregs[1].dttk_value;
4876 char *s;
4877 int i, len, depth = 0;
4878
4879 /*
4880 * Due to all the pointer jumping we do and context we must
4881 * rely upon, we just mandate that the user must have kernel
4882 * read privileges to use this routine.
4883 */
4884 if ((mstate->dtms_access & DTRACE_ACCESS_KERNEL) == 0) {
4885 *flags |= CPU_DTRACE_KPRIV;
4886 *illval = daddr;
4887 regs[rd] = NULL;
4888 }
4889
4890 if (!DTRACE_INSCRATCH(mstate, size)) {
4891 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
4892 regs[rd] = NULL;
4893 break;
4894 }
4895
4896 *end = '\0';
4897
4898 /*
4899 * We want to have a name for the minor. In order to do this,
4900 * we need to walk the minor list from the devinfo. We want
4901 * to be sure that we don't infinitely walk a circular list,
4902 * so we check for circularity by sending a scout pointer
4903 * ahead two elements for every element that we iterate over;
4904 * if the list is circular, these will ultimately point to the
4905 * same element. You may recognize this little trick as the
4906 * answer to a stupid interview question -- one that always
4907 * seems to be asked by those who had to have it laboriously
4908 * explained to them, and who can't even concisely describe
4909 * the conditions under which one would be forced to resort to
4910 * this technique. Needless to say, those conditions are
4911 * found here -- and probably only here. Is this the only use
4912 * of this infamous trick in shipping, production code? If it
4913 * isn't, it probably should be...
4914 */
4915 if (minor != -1) {
4916 uintptr_t maddr = dtrace_loadptr(daddr +
4917 offsetof(struct dev_info, devi_minor));
4918
4919 uintptr_t next = offsetof(struct ddi_minor_data, next);
4920 uintptr_t name = offsetof(struct ddi_minor_data,
4921 d_minor) + offsetof(struct ddi_minor, name);
4922 uintptr_t dev = offsetof(struct ddi_minor_data,
4923 d_minor) + offsetof(struct ddi_minor, dev);
4924 uintptr_t scout;
4925
4926 if (maddr != NULL)
4927 scout = dtrace_loadptr(maddr + next);
4928
4929 while (maddr != NULL && !(*flags & CPU_DTRACE_FAULT)) {
4930 uint64_t m;
4931 #ifdef _LP64
4932 m = dtrace_load64(maddr + dev) & MAXMIN64;
4933 #else
4934 m = dtrace_load32(maddr + dev) & MAXMIN;
4935 #endif
4936 if (m != minor) {
4937 maddr = dtrace_loadptr(maddr + next);
4938
4939 if (scout == NULL)
4940 continue;
4941
4942 scout = dtrace_loadptr(scout + next);
4943
4944 if (scout == NULL)
4945 continue;
4946
4947 scout = dtrace_loadptr(scout + next);
4948
4949 if (scout == NULL)
4950 continue;
4951
4952 if (scout == maddr) {
4953 *flags |= CPU_DTRACE_ILLOP;
4954 break;
4955 }
4956
4957 continue;
4958 }
4959
4960 /*
4961 * We have the minor data. Now we need to
4962 * copy the minor's name into the end of the
4963 * pathname.
4964 */
4965 s = (char *)dtrace_loadptr(maddr + name);
4966 len = dtrace_strlen(s, size);
4967
4968 if (*flags & CPU_DTRACE_FAULT)
4969 break;
4970
4971 if (len != 0) {
4972 if ((end -= (len + 1)) < start)
4973 break;
4974
4975 *end = ':';
4976 }
4977
4978 for (i = 1; i <= len; i++)
4979 end[i] = dtrace_load8((uintptr_t)s++);
4980 break;
4981 }
4982 }
4983
4984 while (daddr != NULL && !(*flags & CPU_DTRACE_FAULT)) {
4985 ddi_node_state_t devi_state;
4986
4987 devi_state = dtrace_load32(daddr +
4988 offsetof(struct dev_info, devi_node_state));
4989
4990 if (*flags & CPU_DTRACE_FAULT)
4991 break;
4992
4993 if (devi_state >= DS_INITIALIZED) {
4994 s = (char *)dtrace_loadptr(daddr +
4995 offsetof(struct dev_info, devi_addr));
4996 len = dtrace_strlen(s, size);
4997
4998 if (*flags & CPU_DTRACE_FAULT)
4999 break;
5000
5001 if (len != 0) {
5002 if ((end -= (len + 1)) < start)
5003 break;
5004
5005 *end = '@';
5006 }
5007
5008 for (i = 1; i <= len; i++)
5009 end[i] = dtrace_load8((uintptr_t)s++);
5010 }
5011
5012 /*
5013 * Now for the node name...
5014 */
5015 s = (char *)dtrace_loadptr(daddr +
5016 offsetof(struct dev_info, devi_node_name));
5017
5018 daddr = dtrace_loadptr(daddr +
5019 offsetof(struct dev_info, devi_parent));
5020
5021 /*
5022 * If our parent is NULL (that is, if we're the root
5023 * node), we're going to use the special path
5024 * "devices".
5025 */
5026 if (daddr == NULL)
5027 s = "devices";
5028
5029 len = dtrace_strlen(s, size);
5030 if (*flags & CPU_DTRACE_FAULT)
5031 break;
5032
5033 if ((end -= (len + 1)) < start)
5034 break;
5035
5036 for (i = 1; i <= len; i++)
5037 end[i] = dtrace_load8((uintptr_t)s++);
5038 *end = '/';
5039
5040 if (depth++ > dtrace_devdepth_max) {
5041 *flags |= CPU_DTRACE_ILLOP;
5042 break;
5043 }
5044 }
5045
5046 if (end < start)
5047 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
5048
5049 if (daddr == NULL) {
5050 regs[rd] = (uintptr_t)end;
5051 mstate->dtms_scratch_ptr += size;
5052 }
5053
5054 break;
5055 }
5056
5057 case DIF_SUBR_STRJOIN: {
5058 char *d = (char *)mstate->dtms_scratch_ptr;
5059 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
5060 uintptr_t s1 = tupregs[0].dttk_value;
5061 uintptr_t s2 = tupregs[1].dttk_value;
5062 int i = 0, j = 0;
5063 size_t lim1, lim2;
5064 char c;
5065
5066 if (!dtrace_strcanload(s1, size, &lim1, mstate, vstate) ||
5067 !dtrace_strcanload(s2, size, &lim2, mstate, vstate)) {
5068 regs[rd] = NULL;
5069 break;
5070 }
5071
5072 if (!DTRACE_INSCRATCH(mstate, size)) {
5073 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
5074 regs[rd] = NULL;
5075 break;
5076 }
5077
5078 for (;;) {
5079 if (i >= size) {
5080 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
5081 regs[rd] = NULL;
5082 break;
5083 }
5084 c = (i >= lim1) ? '\0' : dtrace_load8(s1++);
5085 if ((d[i++] = c) == '\0') {
5086 i--;
5087 break;
5088 }
5089 }
5090
5091 for (;;) {
5092 if (i >= size) {
5093 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
5094 regs[rd] = NULL;
5095 break;
5096 }
5097
5098 c = (j++ >= lim2) ? '\0' : dtrace_load8(s2++);
5099 if ((d[i++] = c) == '\0')
5100 break;
5101 }
5102
5103 if (i < size) {
5104 mstate->dtms_scratch_ptr += i;
5105 regs[rd] = (uintptr_t)d;
5106 }
5107
5108 break;
5109 }
5110
5111 case DIF_SUBR_STRTOLL: {
5112 uintptr_t s = tupregs[0].dttk_value;
5113 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
5114 size_t lim;
5115 int base = 10;
5116
5117 if (nargs > 1) {
5118 if ((base = tupregs[1].dttk_value) <= 1 ||
5119 base > ('z' - 'a' + 1) + ('9' - '0' + 1)) {
5120 *flags |= CPU_DTRACE_ILLOP;
5121 break;
5122 }
5123 }
5124
5125 if (!dtrace_strcanload(s, size, &lim, mstate, vstate)) {
5126 regs[rd] = INT64_MIN;
5127 break;
5128 }
5129
5130 regs[rd] = dtrace_strtoll((char *)s, base, lim);
5131 break;
5132 }
5133
5134 case DIF_SUBR_LLTOSTR: {
5135 int64_t i = (int64_t)tupregs[0].dttk_value;
5136 uint64_t val, digit;
5137 uint64_t size = 65; /* enough room for 2^64 in binary */
5138 char *end = (char *)mstate->dtms_scratch_ptr + size - 1;
5139 int base = 10;
5140
5141 if (nargs > 1) {
5142 if ((base = tupregs[1].dttk_value) <= 1 ||
5143 base > ('z' - 'a' + 1) + ('9' - '0' + 1)) {
5144 *flags |= CPU_DTRACE_ILLOP;
5145 break;
5146 }
5147 }
5148
5149 val = (base == 10 && i < 0) ? i * -1 : i;
5150
5151 if (!DTRACE_INSCRATCH(mstate, size)) {
5152 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
5153 regs[rd] = NULL;
5154 break;
5155 }
5156
5157 for (*end-- = '\0'; val; val /= base) {
5158 if ((digit = val % base) <= '9' - '0') {
5159 *end-- = '0' + digit;
5160 } else {
5161 *end-- = 'a' + (digit - ('9' - '0') - 1);
5162 }
5163 }
5164
5165 if (i == 0 && base == 16)
5166 *end-- = '0';
5167
5168 if (base == 16)
5169 *end-- = 'x';
5170
5171 if (i == 0 || base == 8 || base == 16)
5172 *end-- = '0';
5173
5174 if (i < 0 && base == 10)
5175 *end-- = '-';
5176
5177 regs[rd] = (uintptr_t)end + 1;
5178 mstate->dtms_scratch_ptr += size;
5179 break;
5180 }
5181
5182 case DIF_SUBR_HTONS:
5183 case DIF_SUBR_NTOHS:
5184 #ifdef _BIG_ENDIAN
5185 regs[rd] = (uint16_t)tupregs[0].dttk_value;
5186 #else
5187 regs[rd] = DT_BSWAP_16((uint16_t)tupregs[0].dttk_value);
5188 #endif
5189 break;
5190
5191
5192 case DIF_SUBR_HTONL:
5193 case DIF_SUBR_NTOHL:
5194 #ifdef _BIG_ENDIAN
5195 regs[rd] = (uint32_t)tupregs[0].dttk_value;
5196 #else
5197 regs[rd] = DT_BSWAP_32((uint32_t)tupregs[0].dttk_value);
5198 #endif
5199 break;
5200
5201
5202 case DIF_SUBR_HTONLL:
5203 case DIF_SUBR_NTOHLL:
5204 #ifdef _BIG_ENDIAN
5205 regs[rd] = (uint64_t)tupregs[0].dttk_value;
5206 #else
5207 regs[rd] = DT_BSWAP_64((uint64_t)tupregs[0].dttk_value);
5208 #endif
5209 break;
5210
5211
5212 case DIF_SUBR_DIRNAME:
5213 case DIF_SUBR_BASENAME: {
5214 char *dest = (char *)mstate->dtms_scratch_ptr;
5215 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
5216 uintptr_t src = tupregs[0].dttk_value;
5217 int i, j, len = dtrace_strlen((char *)src, size);
5218 int lastbase = -1, firstbase = -1, lastdir = -1;
5219 int start, end;
5220
5221 if (!dtrace_canload(src, len + 1, mstate, vstate)) {
5222 regs[rd] = NULL;
5223 break;
5224 }
5225
5226 if (!DTRACE_INSCRATCH(mstate, size)) {
5227 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
5228 regs[rd] = NULL;
5229 break;
5230 }
5231
5232 /*
5233 * The basename and dirname for a zero-length string is
5234 * defined to be "."
5235 */
5236 if (len == 0) {
5237 len = 1;
5238 src = (uintptr_t)".";
5239 }
5240
5241 /*
5242 * Start from the back of the string, moving back toward the
5243 * front until we see a character that isn't a slash. That
5244 * character is the last character in the basename.
5245 */
5246 for (i = len - 1; i >= 0; i--) {
5247 if (dtrace_load8(src + i) != '/')
5248 break;
5249 }
5250
5251 if (i >= 0)
5252 lastbase = i;
5253
5254 /*
5255 * Starting from the last character in the basename, move
5256 * towards the front until we find a slash. The character
5257 * that we processed immediately before that is the first
5258 * character in the basename.
5259 */
5260 for (; i >= 0; i--) {
5261 if (dtrace_load8(src + i) == '/')
5262 break;
5263 }
5264
5265 if (i >= 0)
5266 firstbase = i + 1;
5267
5268 /*
5269 * Now keep going until we find a non-slash character. That
5270 * character is the last character in the dirname.
5271 */
5272 for (; i >= 0; i--) {
5273 if (dtrace_load8(src + i) != '/')
5274 break;
5275 }
5276
5277 if (i >= 0)
5278 lastdir = i;
5279
5280 ASSERT(!(lastbase == -1 && firstbase != -1));
5281 ASSERT(!(firstbase == -1 && lastdir != -1));
5282
5283 if (lastbase == -1) {
5284 /*
5285 * We didn't find a non-slash character. We know that
5286 * the length is non-zero, so the whole string must be
5287 * slashes. In either the dirname or the basename
5288 * case, we return '/'.
5289 */
5290 ASSERT(firstbase == -1);
5291 firstbase = lastbase = lastdir = 0;
5292 }
5293
5294 if (firstbase == -1) {
5295 /*
5296 * The entire string consists only of a basename
5297 * component. If we're looking for dirname, we need
5298 * to change our string to be just "."; if we're
5299 * looking for a basename, we'll just set the first
5300 * character of the basename to be 0.
5301 */
5302 if (subr == DIF_SUBR_DIRNAME) {
5303 ASSERT(lastdir == -1);
5304 src = (uintptr_t)".";
5305 lastdir = 0;
5306 } else {
5307 firstbase = 0;
5308 }
5309 }
5310
5311 if (subr == DIF_SUBR_DIRNAME) {
5312 if (lastdir == -1) {
5313 /*
5314 * We know that we have a slash in the name --
5315 * or lastdir would be set to 0, above. And
5316 * because lastdir is -1, we know that this
5317 * slash must be the first character. (That
5318 * is, the full string must be of the form
5319 * "/basename".) In this case, the last
5320 * character of the directory name is 0.
5321 */
5322 lastdir = 0;
5323 }
5324
5325 start = 0;
5326 end = lastdir;
5327 } else {
5328 ASSERT(subr == DIF_SUBR_BASENAME);
5329 ASSERT(firstbase != -1 && lastbase != -1);
5330 start = firstbase;
5331 end = lastbase;
5332 }
5333
5334 for (i = start, j = 0; i <= end && j < size - 1; i++, j++)
5335 dest[j] = dtrace_load8(src + i);
5336
5337 dest[j] = '\0';
5338 regs[rd] = (uintptr_t)dest;
5339 mstate->dtms_scratch_ptr += size;
5340 break;
5341 }
5342
5343 case DIF_SUBR_GETF: {
5344 uintptr_t fd = tupregs[0].dttk_value;
5345 uf_info_t *finfo = &curthread->t_procp->p_user.u_finfo;
5346 file_t *fp;
5347
5348 if (!dtrace_priv_proc(state, mstate)) {
5349 regs[rd] = NULL;
5350 break;
5351 }
5352
5353 /*
5354 * This is safe because fi_nfiles only increases, and the
5355 * fi_list array is not freed when the array size doubles.
5356 * (See the comment in flist_grow() for details on the
5357 * management of the u_finfo structure.)
5358 */
5359 fp = fd < finfo->fi_nfiles ? finfo->fi_list[fd].uf_file : NULL;
5360
5361 mstate->dtms_getf = fp;
5362 regs[rd] = (uintptr_t)fp;
5363 break;
5364 }
5365
5366 case DIF_SUBR_CLEANPATH: {
5367 char *dest = (char *)mstate->dtms_scratch_ptr, c;
5368 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
5369 uintptr_t src = tupregs[0].dttk_value;
5370 size_t lim;
5371 int i = 0, j = 0;
5372 zone_t *z;
5373
5374 if (!dtrace_strcanload(src, size, &lim, mstate, vstate)) {
5375 regs[rd] = NULL;
5376 break;
5377 }
5378
5379 if (!DTRACE_INSCRATCH(mstate, size)) {
5380 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
5381 regs[rd] = NULL;
5382 break;
5383 }
5384
5385 /*
5386 * Move forward, loading each character.
5387 */
5388 do {
5389 c = (i >= lim) ? '\0' : dtrace_load8(src + i++);
5390 next:
5391 if (j + 5 >= size) /* 5 = strlen("/..c\0") */
5392 break;
5393
5394 if (c != '/') {
5395 dest[j++] = c;
5396 continue;
5397 }
5398
5399 c = (i >= lim) ? '\0' : dtrace_load8(src + i++);
5400
5401 if (c == '/') {
5402 /*
5403 * We have two slashes -- we can just advance
5404 * to the next character.
5405 */
5406 goto next;
5407 }
5408
5409 if (c != '.') {
5410 /*
5411 * This is not "." and it's not ".." -- we can
5412 * just store the "/" and this character and
5413 * drive on.
5414 */
5415 dest[j++] = '/';
5416 dest[j++] = c;
5417 continue;
5418 }
5419
5420 c = (i >= lim) ? '\0' : dtrace_load8(src + i++);
5421
5422 if (c == '/') {
5423 /*
5424 * This is a "/./" component. We're not going
5425 * to store anything in the destination buffer;
5426 * we're just going to go to the next component.
5427 */
5428 goto next;
5429 }
5430
5431 if (c != '.') {
5432 /*
5433 * This is not ".." -- we can just store the
5434 * "/." and this character and continue
5435 * processing.
5436 */
5437 dest[j++] = '/';
5438 dest[j++] = '.';
5439 dest[j++] = c;
5440 continue;
5441 }
5442
5443 c = (i >= lim) ? '\0' : dtrace_load8(src + i++);
5444
5445 if (c != '/' && c != '\0') {
5446 /*
5447 * This is not ".." -- it's "..[mumble]".
5448 * We'll store the "/.." and this character
5449 * and continue processing.
5450 */
5451 dest[j++] = '/';
5452 dest[j++] = '.';
5453 dest[j++] = '.';
5454 dest[j++] = c;
5455 continue;
5456 }
5457
5458 /*
5459 * This is "/../" or "/..\0". We need to back up
5460 * our destination pointer until we find a "/".
5461 */
5462 i--;
5463 while (j != 0 && dest[--j] != '/')
5464 continue;
5465
5466 if (c == '\0')
5467 dest[++j] = '/';
5468 } while (c != '\0');
5469
5470 dest[j] = '\0';
5471
5472 if (mstate->dtms_getf != NULL &&
5473 !(mstate->dtms_access & DTRACE_ACCESS_KERNEL) &&
5474 (z = state->dts_cred.dcr_cred->cr_zone) != kcred->cr_zone) {
5475 /*
5476 * If we've done a getf() as a part of this ECB and we
5477 * don't have kernel access (and we're not in the global
5478 * zone), check if the path we cleaned up begins with
5479 * the zone's root path, and trim it off if so. Note
5480 * that this is an output cleanliness issue, not a
5481 * security issue: knowing one's zone root path does
5482 * not enable privilege escalation.
5483 */
5484 if (strstr(dest, z->zone_rootpath) == dest)
5485 dest += strlen(z->zone_rootpath) - 1;
5486 }
5487
5488 regs[rd] = (uintptr_t)dest;
5489 mstate->dtms_scratch_ptr += size;
5490 break;
5491 }
5492
5493 case DIF_SUBR_INET_NTOA:
5494 case DIF_SUBR_INET_NTOA6:
5495 case DIF_SUBR_INET_NTOP: {
5496 size_t size;
5497 int af, argi, i;
5498 char *base, *end;
5499
5500 if (subr == DIF_SUBR_INET_NTOP) {
5501 af = (int)tupregs[0].dttk_value;
5502 argi = 1;
5503 } else {
5504 af = subr == DIF_SUBR_INET_NTOA ? AF_INET: AF_INET6;
5505 argi = 0;
5506 }
5507
5508 if (af == AF_INET) {
5509 ipaddr_t ip4;
5510 uint8_t *ptr8, val;
5511
5512 if (!dtrace_canload(tupregs[argi].dttk_value,
5513 sizeof (ipaddr_t), mstate, vstate)) {
5514 regs[rd] = NULL;
5515 break;
5516 }
5517
5518 /*
5519 * Safely load the IPv4 address.
5520 */
5521 ip4 = dtrace_load32(tupregs[argi].dttk_value);
5522
5523 /*
5524 * Check an IPv4 string will fit in scratch.
5525 */
5526 size = INET_ADDRSTRLEN;
5527 if (!DTRACE_INSCRATCH(mstate, size)) {
5528 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
5529 regs[rd] = NULL;
5530 break;
5531 }
5532 base = (char *)mstate->dtms_scratch_ptr;
5533 end = (char *)mstate->dtms_scratch_ptr + size - 1;
5534
5535 /*
5536 * Stringify as a dotted decimal quad.
5537 */
5538 *end-- = '\0';
5539 ptr8 = (uint8_t *)&ip4;
5540 for (i = 3; i >= 0; i--) {
5541 val = ptr8[i];
5542
5543 if (val == 0) {
5544 *end-- = '0';
5545 } else {
5546 for (; val; val /= 10) {
5547 *end-- = '0' + (val % 10);
5548 }
5549 }
5550
5551 if (i > 0)
5552 *end-- = '.';
5553 }
5554 ASSERT(end + 1 >= base);
5555
5556 } else if (af == AF_INET6) {
5557 struct in6_addr ip6;
5558 int firstzero, tryzero, numzero, v6end;
5559 uint16_t val;
5560 const char digits[] = "0123456789abcdef";
5561
5562 /*
5563 * Stringify using RFC 1884 convention 2 - 16 bit
5564 * hexadecimal values with a zero-run compression.
5565 * Lower case hexadecimal digits are used.
5566 * eg, fe80::214:4fff:fe0b:76c8.
5567 * The IPv4 embedded form is returned for inet_ntop,
5568 * just the IPv4 string is returned for inet_ntoa6.
5569 */
5570
5571 if (!dtrace_canload(tupregs[argi].dttk_value,
5572 sizeof (struct in6_addr), mstate, vstate)) {
5573 regs[rd] = NULL;
5574 break;
5575 }
5576
5577 /*
5578 * Safely load the IPv6 address.
5579 */
5580 dtrace_bcopy(
5581 (void *)(uintptr_t)tupregs[argi].dttk_value,
5582 (void *)(uintptr_t)&ip6, sizeof (struct in6_addr));
5583
5584 /*
5585 * Check an IPv6 string will fit in scratch.
5586 */
5587 size = INET6_ADDRSTRLEN;
5588 if (!DTRACE_INSCRATCH(mstate, size)) {
5589 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
5590 regs[rd] = NULL;
5591 break;
5592 }
5593 base = (char *)mstate->dtms_scratch_ptr;
5594 end = (char *)mstate->dtms_scratch_ptr + size - 1;
5595 *end-- = '\0';
5596
5597 /*
5598 * Find the longest run of 16 bit zero values
5599 * for the single allowed zero compression - "::".
5600 */
5601 firstzero = -1;
5602 tryzero = -1;
5603 numzero = 1;
5604 for (i = 0; i < sizeof (struct in6_addr); i++) {
5605 if (ip6._S6_un._S6_u8[i] == 0 &&
5606 tryzero == -1 && i % 2 == 0) {
5607 tryzero = i;
5608 continue;
5609 }
5610
5611 if (tryzero != -1 &&
5612 (ip6._S6_un._S6_u8[i] != 0 ||
5613 i == sizeof (struct in6_addr) - 1)) {
5614
5615 if (i - tryzero <= numzero) {
5616 tryzero = -1;
5617 continue;
5618 }
5619
5620 firstzero = tryzero;
5621 numzero = i - i % 2 - tryzero;
5622 tryzero = -1;
5623
5624 if (ip6._S6_un._S6_u8[i] == 0 &&
5625 i == sizeof (struct in6_addr) - 1)
5626 numzero += 2;
5627 }
5628 }
5629 ASSERT(firstzero + numzero <= sizeof (struct in6_addr));
5630
5631 /*
5632 * Check for an IPv4 embedded address.
5633 */
5634 v6end = sizeof (struct in6_addr) - 2;
5635 if (IN6_IS_ADDR_V4MAPPED(&ip6) ||
5636 IN6_IS_ADDR_V4COMPAT(&ip6)) {
5637 for (i = sizeof (struct in6_addr) - 1;
5638 i >= DTRACE_V4MAPPED_OFFSET; i--) {
5639 ASSERT(end >= base);
5640
5641 val = ip6._S6_un._S6_u8[i];
5642
5643 if (val == 0) {
5644 *end-- = '0';
5645 } else {
5646 for (; val; val /= 10) {
5647 *end-- = '0' + val % 10;
5648 }
5649 }
5650
5651 if (i > DTRACE_V4MAPPED_OFFSET)
5652 *end-- = '.';
5653 }
5654
5655 if (subr == DIF_SUBR_INET_NTOA6)
5656 goto inetout;
5657
5658 /*
5659 * Set v6end to skip the IPv4 address that
5660 * we have already stringified.
5661 */
5662 v6end = 10;
5663 }
5664
5665 /*
5666 * Build the IPv6 string by working through the
5667 * address in reverse.
5668 */
5669 for (i = v6end; i >= 0; i -= 2) {
5670 ASSERT(end >= base);
5671
5672 if (i == firstzero + numzero - 2) {
5673 *end-- = ':';
5674 *end-- = ':';
5675 i -= numzero - 2;
5676 continue;
5677 }
5678
5679 if (i < 14 && i != firstzero - 2)
5680 *end-- = ':';
5681
5682 val = (ip6._S6_un._S6_u8[i] << 8) +
5683 ip6._S6_un._S6_u8[i + 1];
5684
5685 if (val == 0) {
5686 *end-- = '0';
5687 } else {
5688 for (; val; val /= 16) {
5689 *end-- = digits[val % 16];
5690 }
5691 }
5692 }
5693 ASSERT(end + 1 >= base);
5694
5695 } else {
5696 /*
5697 * The user didn't use AH_INET or AH_INET6.
5698 */
5699 DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP);
5700 regs[rd] = NULL;
5701 break;
5702 }
5703
5704 inetout: regs[rd] = (uintptr_t)end + 1;
5705 mstate->dtms_scratch_ptr += size;
5706 break;
5707 }
5708
5709 }
5710 }
5711
5712 /*
5713 * Emulate the execution of DTrace IR instructions specified by the given
5714 * DIF object. This function is deliberately void of assertions as all of
5715 * the necessary checks are handled by a call to dtrace_difo_validate().
5716 */
5717 static uint64_t
5718 dtrace_dif_emulate(dtrace_difo_t *difo, dtrace_mstate_t *mstate,
5719 dtrace_vstate_t *vstate, dtrace_state_t *state)
5720 {
5721 const dif_instr_t *text = difo->dtdo_buf;
5722 const uint_t textlen = difo->dtdo_len;
5723 const char *strtab = difo->dtdo_strtab;
5724 const uint64_t *inttab = difo->dtdo_inttab;
5725
5726 uint64_t rval = 0;
5727 dtrace_statvar_t *svar;
5728 dtrace_dstate_t *dstate = &vstate->dtvs_dynvars;
5729 dtrace_difv_t *v;
5730 volatile uint16_t *flags = &cpu_core[CPU->cpu_id].cpuc_dtrace_flags;
5731 volatile uintptr_t *illval = &cpu_core[CPU->cpu_id].cpuc_dtrace_illval;
5732
5733 dtrace_key_t tupregs[DIF_DTR_NREGS + 2]; /* +2 for thread and id */
5734 uint64_t regs[DIF_DIR_NREGS];
5735 uint64_t *tmp;
5736
5737 uint8_t cc_n = 0, cc_z = 0, cc_v = 0, cc_c = 0;
5738 int64_t cc_r;
5739 uint_t pc = 0, id, opc;
5740 uint8_t ttop = 0;
5741 dif_instr_t instr;
5742 uint_t r1, r2, rd;
5743
5744 /*
5745 * We stash the current DIF object into the machine state: we need it
5746 * for subsequent access checking.
5747 */
5748 mstate->dtms_difo = difo;
5749
5750 regs[DIF_REG_R0] = 0; /* %r0 is fixed at zero */
5751
5752 while (pc < textlen && !(*flags & CPU_DTRACE_FAULT)) {
5753 opc = pc;
5754
5755 instr = text[pc++];
5756 r1 = DIF_INSTR_R1(instr);
5757 r2 = DIF_INSTR_R2(instr);
5758 rd = DIF_INSTR_RD(instr);
5759
5760 switch (DIF_INSTR_OP(instr)) {
5761 case DIF_OP_OR:
5762 regs[rd] = regs[r1] | regs[r2];
5763 break;
5764 case DIF_OP_XOR:
5765 regs[rd] = regs[r1] ^ regs[r2];
5766 break;
5767 case DIF_OP_AND:
5768 regs[rd] = regs[r1] & regs[r2];
5769 break;
5770 case DIF_OP_SLL:
5771 regs[rd] = regs[r1] << regs[r2];
5772 break;
5773 case DIF_OP_SRL:
5774 regs[rd] = regs[r1] >> regs[r2];
5775 break;
5776 case DIF_OP_SUB:
5777 regs[rd] = regs[r1] - regs[r2];
5778 break;
5779 case DIF_OP_ADD:
5780 regs[rd] = regs[r1] + regs[r2];
5781 break;
5782 case DIF_OP_MUL:
5783 regs[rd] = regs[r1] * regs[r2];
5784 break;
5785 case DIF_OP_SDIV:
5786 if (regs[r2] == 0) {
5787 regs[rd] = 0;
5788 *flags |= CPU_DTRACE_DIVZERO;
5789 } else {
5790 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
5791 regs[rd] = (int64_t)regs[r1] /
5792 (int64_t)regs[r2];
5793 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
5794 }
5795 break;
5796
5797 case DIF_OP_UDIV:
5798 if (regs[r2] == 0) {
5799 regs[rd] = 0;
5800 *flags |= CPU_DTRACE_DIVZERO;
5801 } else {
5802 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
5803 regs[rd] = regs[r1] / regs[r2];
5804 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
5805 }
5806 break;
5807
5808 case DIF_OP_SREM:
5809 if (regs[r2] == 0) {
5810 regs[rd] = 0;
5811 *flags |= CPU_DTRACE_DIVZERO;
5812 } else {
5813 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
5814 regs[rd] = (int64_t)regs[r1] %
5815 (int64_t)regs[r2];
5816 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
5817 }
5818 break;
5819
5820 case DIF_OP_UREM:
5821 if (regs[r2] == 0) {
5822 regs[rd] = 0;
5823 *flags |= CPU_DTRACE_DIVZERO;
5824 } else {
5825 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
5826 regs[rd] = regs[r1] % regs[r2];
5827 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
5828 }
5829 break;
5830
5831 case DIF_OP_NOT:
5832 regs[rd] = ~regs[r1];
5833 break;
5834 case DIF_OP_MOV:
5835 regs[rd] = regs[r1];
5836 break;
5837 case DIF_OP_CMP:
5838 cc_r = regs[r1] - regs[r2];
5839 cc_n = cc_r < 0;
5840 cc_z = cc_r == 0;
5841 cc_v = 0;
5842 cc_c = regs[r1] < regs[r2];
5843 break;
5844 case DIF_OP_TST:
5845 cc_n = cc_v = cc_c = 0;
5846 cc_z = regs[r1] == 0;
5847 break;
5848 case DIF_OP_BA:
5849 pc = DIF_INSTR_LABEL(instr);
5850 break;
5851 case DIF_OP_BE:
5852 if (cc_z)
5853 pc = DIF_INSTR_LABEL(instr);
5854 break;
5855 case DIF_OP_BNE:
5856 if (cc_z == 0)
5857 pc = DIF_INSTR_LABEL(instr);
5858 break;
5859 case DIF_OP_BG:
5860 if ((cc_z | (cc_n ^ cc_v)) == 0)
5861 pc = DIF_INSTR_LABEL(instr);
5862 break;
5863 case DIF_OP_BGU:
5864 if ((cc_c | cc_z) == 0)
5865 pc = DIF_INSTR_LABEL(instr);
5866 break;
5867 case DIF_OP_BGE:
5868 if ((cc_n ^ cc_v) == 0)
5869 pc = DIF_INSTR_LABEL(instr);
5870 break;
5871 case DIF_OP_BGEU:
5872 if (cc_c == 0)
5873 pc = DIF_INSTR_LABEL(instr);
5874 break;
5875 case DIF_OP_BL:
5876 if (cc_n ^ cc_v)
5877 pc = DIF_INSTR_LABEL(instr);
5878 break;
5879 case DIF_OP_BLU:
5880 if (cc_c)
5881 pc = DIF_INSTR_LABEL(instr);
5882 break;
5883 case DIF_OP_BLE:
5884 if (cc_z | (cc_n ^ cc_v))
5885 pc = DIF_INSTR_LABEL(instr);
5886 break;
5887 case DIF_OP_BLEU:
5888 if (cc_c | cc_z)
5889 pc = DIF_INSTR_LABEL(instr);
5890 break;
5891 case DIF_OP_RLDSB:
5892 if (!dtrace_canload(regs[r1], 1, mstate, vstate))
5893 break;
5894 /*FALLTHROUGH*/
5895 case DIF_OP_LDSB:
5896 regs[rd] = (int8_t)dtrace_load8(regs[r1]);
5897 break;
5898 case DIF_OP_RLDSH:
5899 if (!dtrace_canload(regs[r1], 2, mstate, vstate))
5900 break;
5901 /*FALLTHROUGH*/
5902 case DIF_OP_LDSH:
5903 regs[rd] = (int16_t)dtrace_load16(regs[r1]);
5904 break;
5905 case DIF_OP_RLDSW:
5906 if (!dtrace_canload(regs[r1], 4, mstate, vstate))
5907 break;
5908 /*FALLTHROUGH*/
5909 case DIF_OP_LDSW:
5910 regs[rd] = (int32_t)dtrace_load32(regs[r1]);
5911 break;
5912 case DIF_OP_RLDUB:
5913 if (!dtrace_canload(regs[r1], 1, mstate, vstate))
5914 break;
5915 /*FALLTHROUGH*/
5916 case DIF_OP_LDUB:
5917 regs[rd] = dtrace_load8(regs[r1]);
5918 break;
5919 case DIF_OP_RLDUH:
5920 if (!dtrace_canload(regs[r1], 2, mstate, vstate))
5921 break;
5922 /*FALLTHROUGH*/
5923 case DIF_OP_LDUH:
5924 regs[rd] = dtrace_load16(regs[r1]);
5925 break;
5926 case DIF_OP_RLDUW:
5927 if (!dtrace_canload(regs[r1], 4, mstate, vstate))
5928 break;
5929 /*FALLTHROUGH*/
5930 case DIF_OP_LDUW:
5931 regs[rd] = dtrace_load32(regs[r1]);
5932 break;
5933 case DIF_OP_RLDX:
5934 if (!dtrace_canload(regs[r1], 8, mstate, vstate))
5935 break;
5936 /*FALLTHROUGH*/
5937 case DIF_OP_LDX:
5938 regs[rd] = dtrace_load64(regs[r1]);
5939 break;
5940 case DIF_OP_ULDSB:
5941 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
5942 regs[rd] = (int8_t)
5943 dtrace_fuword8((void *)(uintptr_t)regs[r1]);
5944 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
5945 break;
5946 case DIF_OP_ULDSH:
5947 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
5948 regs[rd] = (int16_t)
5949 dtrace_fuword16((void *)(uintptr_t)regs[r1]);
5950 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
5951 break;
5952 case DIF_OP_ULDSW:
5953 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
5954 regs[rd] = (int32_t)
5955 dtrace_fuword32((void *)(uintptr_t)regs[r1]);
5956 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
5957 break;
5958 case DIF_OP_ULDUB:
5959 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
5960 regs[rd] =
5961 dtrace_fuword8((void *)(uintptr_t)regs[r1]);
5962 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
5963 break;
5964 case DIF_OP_ULDUH:
5965 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
5966 regs[rd] =
5967 dtrace_fuword16((void *)(uintptr_t)regs[r1]);
5968 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
5969 break;
5970 case DIF_OP_ULDUW:
5971 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
5972 regs[rd] =
5973 dtrace_fuword32((void *)(uintptr_t)regs[r1]);
5974 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
5975 break;
5976 case DIF_OP_ULDX:
5977 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
5978 regs[rd] =
5979 dtrace_fuword64((void *)(uintptr_t)regs[r1]);
5980 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
5981 break;
5982 case DIF_OP_RET:
5983 rval = regs[rd];
5984 pc = textlen;
5985 break;
5986 case DIF_OP_NOP:
5987 break;
5988 case DIF_OP_SETX:
5989 regs[rd] = inttab[DIF_INSTR_INTEGER(instr)];
5990 break;
5991 case DIF_OP_SETS:
5992 regs[rd] = (uint64_t)(uintptr_t)
5993 (strtab + DIF_INSTR_STRING(instr));
5994 break;
5995 case DIF_OP_SCMP: {
5996 size_t sz = state->dts_options[DTRACEOPT_STRSIZE];
5997 uintptr_t s1 = regs[r1];
5998 uintptr_t s2 = regs[r2];
5999 size_t lim1, lim2;
6000
6001 if (s1 != NULL &&
6002 !dtrace_strcanload(s1, sz, &lim1, mstate, vstate))
6003 break;
6004 if (s2 != NULL &&
6005 !dtrace_strcanload(s2, sz, &lim2, mstate, vstate))
6006 break;
6007
6008 cc_r = dtrace_strncmp((char *)s1, (char *)s2,
6009 MIN(lim1, lim2));
6010
6011 cc_n = cc_r < 0;
6012 cc_z = cc_r == 0;
6013 cc_v = cc_c = 0;
6014 break;
6015 }
6016 case DIF_OP_LDGA:
6017 regs[rd] = dtrace_dif_variable(mstate, state,
6018 r1, regs[r2]);
6019 break;
6020 case DIF_OP_LDGS:
6021 id = DIF_INSTR_VAR(instr);
6022
6023 if (id >= DIF_VAR_OTHER_UBASE) {
6024 uintptr_t a;
6025
6026 id -= DIF_VAR_OTHER_UBASE;
6027 svar = vstate->dtvs_globals[id];
6028 ASSERT(svar != NULL);
6029 v = &svar->dtsv_var;
6030
6031 if (!(v->dtdv_type.dtdt_flags & DIF_TF_BYREF)) {
6032 regs[rd] = svar->dtsv_data;
6033 break;
6034 }
6035
6036 a = (uintptr_t)svar->dtsv_data;
6037
6038 if (*(uint8_t *)a == UINT8_MAX) {
6039 /*
6040 * If the 0th byte is set to UINT8_MAX
6041 * then this is to be treated as a
6042 * reference to a NULL variable.
6043 */
6044 regs[rd] = NULL;
6045 } else {
6046 regs[rd] = a + sizeof (uint64_t);
6047 }
6048
6049 break;
6050 }
6051
6052 regs[rd] = dtrace_dif_variable(mstate, state, id, 0);
6053 break;
6054
6055 case DIF_OP_STGA:
6056 dtrace_dif_variable_write(mstate, state, r1, regs[r2],
6057 regs[rd]);
6058 break;
6059
6060 case DIF_OP_STGS:
6061 id = DIF_INSTR_VAR(instr);
6062
6063 ASSERT(id >= DIF_VAR_OTHER_UBASE);
6064 id -= DIF_VAR_OTHER_UBASE;
6065
6066 VERIFY(id < vstate->dtvs_nglobals);
6067 svar = vstate->dtvs_globals[id];
6068 ASSERT(svar != NULL);
6069 v = &svar->dtsv_var;
6070
6071 if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) {
6072 uintptr_t a = (uintptr_t)svar->dtsv_data;
6073 size_t lim;
6074
6075 ASSERT(a != NULL);
6076 ASSERT(svar->dtsv_size != 0);
6077
6078 if (regs[rd] == NULL) {
6079 *(uint8_t *)a = UINT8_MAX;
6080 break;
6081 } else {
6082 *(uint8_t *)a = 0;
6083 a += sizeof (uint64_t);
6084 }
6085 if (!dtrace_vcanload(
6086 (void *)(uintptr_t)regs[rd], &v->dtdv_type,
6087 &lim, mstate, vstate))
6088 break;
6089
6090 dtrace_vcopy((void *)(uintptr_t)regs[rd],
6091 (void *)a, &v->dtdv_type, lim);
6092 break;
6093 }
6094
6095 svar->dtsv_data = regs[rd];
6096 break;
6097
6098 case DIF_OP_LDTA:
6099 /*
6100 * There are no DTrace built-in thread-local arrays at
6101 * present. This opcode is saved for future work.
6102 */
6103 *flags |= CPU_DTRACE_ILLOP;
6104 regs[rd] = 0;
6105 break;
6106
6107 case DIF_OP_LDLS:
6108 id = DIF_INSTR_VAR(instr);
6109
6110 if (id < DIF_VAR_OTHER_UBASE) {
6111 /*
6112 * For now, this has no meaning.
6113 */
6114 regs[rd] = 0;
6115 break;
6116 }
6117
6118 id -= DIF_VAR_OTHER_UBASE;
6119
6120 ASSERT(id < vstate->dtvs_nlocals);
6121 ASSERT(vstate->dtvs_locals != NULL);
6122
6123 svar = vstate->dtvs_locals[id];
6124 ASSERT(svar != NULL);
6125 v = &svar->dtsv_var;
6126
6127 if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) {
6128 uintptr_t a = (uintptr_t)svar->dtsv_data;
6129 size_t sz = v->dtdv_type.dtdt_size;
6130
6131 sz += sizeof (uint64_t);
6132 ASSERT(svar->dtsv_size == NCPU * sz);
6133 a += CPU->cpu_id * sz;
6134
6135 if (*(uint8_t *)a == UINT8_MAX) {
6136 /*
6137 * If the 0th byte is set to UINT8_MAX
6138 * then this is to be treated as a
6139 * reference to a NULL variable.
6140 */
6141 regs[rd] = NULL;
6142 } else {
6143 regs[rd] = a + sizeof (uint64_t);
6144 }
6145
6146 break;
6147 }
6148
6149 ASSERT(svar->dtsv_size == NCPU * sizeof (uint64_t));
6150 tmp = (uint64_t *)(uintptr_t)svar->dtsv_data;
6151 regs[rd] = tmp[CPU->cpu_id];
6152 break;
6153
6154 case DIF_OP_STLS:
6155 id = DIF_INSTR_VAR(instr);
6156
6157 ASSERT(id >= DIF_VAR_OTHER_UBASE);
6158 id -= DIF_VAR_OTHER_UBASE;
6159 VERIFY(id < vstate->dtvs_nlocals);
6160
6161 ASSERT(vstate->dtvs_locals != NULL);
6162 svar = vstate->dtvs_locals[id];
6163 ASSERT(svar != NULL);
6164 v = &svar->dtsv_var;
6165
6166 if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) {
6167 uintptr_t a = (uintptr_t)svar->dtsv_data;
6168 size_t sz = v->dtdv_type.dtdt_size;
6169 size_t lim;
6170
6171 sz += sizeof (uint64_t);
6172 ASSERT(svar->dtsv_size == NCPU * sz);
6173 a += CPU->cpu_id * sz;
6174
6175 if (regs[rd] == NULL) {
6176 *(uint8_t *)a = UINT8_MAX;
6177 break;
6178 } else {
6179 *(uint8_t *)a = 0;
6180 a += sizeof (uint64_t);
6181 }
6182
6183 if (!dtrace_vcanload(
6184 (void *)(uintptr_t)regs[rd], &v->dtdv_type,
6185 &lim, mstate, vstate))
6186 break;
6187
6188 dtrace_vcopy((void *)(uintptr_t)regs[rd],
6189 (void *)a, &v->dtdv_type, lim);
6190 break;
6191 }
6192
6193 ASSERT(svar->dtsv_size == NCPU * sizeof (uint64_t));
6194 tmp = (uint64_t *)(uintptr_t)svar->dtsv_data;
6195 tmp[CPU->cpu_id] = regs[rd];
6196 break;
6197
6198 case DIF_OP_LDTS: {
6199 dtrace_dynvar_t *dvar;
6200 dtrace_key_t *key;
6201
6202 id = DIF_INSTR_VAR(instr);
6203 ASSERT(id >= DIF_VAR_OTHER_UBASE);
6204 id -= DIF_VAR_OTHER_UBASE;
6205 v = &vstate->dtvs_tlocals[id];
6206
6207 key = &tupregs[DIF_DTR_NREGS];
6208 key[0].dttk_value = (uint64_t)id;
6209 key[0].dttk_size = 0;
6210 DTRACE_TLS_THRKEY(key[1].dttk_value);
6211 key[1].dttk_size = 0;
6212
6213 dvar = dtrace_dynvar(dstate, 2, key,
6214 sizeof (uint64_t), DTRACE_DYNVAR_NOALLOC,
6215 mstate, vstate);
6216
6217 if (dvar == NULL) {
6218 regs[rd] = 0;
6219 break;
6220 }
6221
6222 if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) {
6223 regs[rd] = (uint64_t)(uintptr_t)dvar->dtdv_data;
6224 } else {
6225 regs[rd] = *((uint64_t *)dvar->dtdv_data);
6226 }
6227
6228 break;
6229 }
6230
6231 case DIF_OP_STTS: {
6232 dtrace_dynvar_t *dvar;
6233 dtrace_key_t *key;
6234
6235 id = DIF_INSTR_VAR(instr);
6236 ASSERT(id >= DIF_VAR_OTHER_UBASE);
6237 id -= DIF_VAR_OTHER_UBASE;
6238 VERIFY(id < vstate->dtvs_ntlocals);
6239
6240 key = &tupregs[DIF_DTR_NREGS];
6241 key[0].dttk_value = (uint64_t)id;
6242 key[0].dttk_size = 0;
6243 DTRACE_TLS_THRKEY(key[1].dttk_value);
6244 key[1].dttk_size = 0;
6245 v = &vstate->dtvs_tlocals[id];
6246
6247 dvar = dtrace_dynvar(dstate, 2, key,
6248 v->dtdv_type.dtdt_size > sizeof (uint64_t) ?
6249 v->dtdv_type.dtdt_size : sizeof (uint64_t),
6250 regs[rd] ? DTRACE_DYNVAR_ALLOC :
6251 DTRACE_DYNVAR_DEALLOC, mstate, vstate);
6252
6253 /*
6254 * Given that we're storing to thread-local data,
6255 * we need to flush our predicate cache.
6256 */
6257 curthread->t_predcache = NULL;
6258
6259 if (dvar == NULL)
6260 break;
6261
6262 if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) {
6263 size_t lim;
6264
6265 if (!dtrace_vcanload(
6266 (void *)(uintptr_t)regs[rd],
6267 &v->dtdv_type, &lim, mstate, vstate))
6268 break;
6269
6270 dtrace_vcopy((void *)(uintptr_t)regs[rd],
6271 dvar->dtdv_data, &v->dtdv_type, lim);
6272 } else {
6273 *((uint64_t *)dvar->dtdv_data) = regs[rd];
6274 }
6275
6276 break;
6277 }
6278
6279 case DIF_OP_SRA:
6280 regs[rd] = (int64_t)regs[r1] >> regs[r2];
6281 break;
6282
6283 case DIF_OP_CALL:
6284 dtrace_dif_subr(DIF_INSTR_SUBR(instr), rd,
6285 regs, tupregs, ttop, mstate, state);
6286 break;
6287
6288 case DIF_OP_PUSHTR:
6289 if (ttop == DIF_DTR_NREGS) {
6290 *flags |= CPU_DTRACE_TUPOFLOW;
6291 break;
6292 }
6293
6294 if (r1 == DIF_TYPE_STRING) {
6295 /*
6296 * If this is a string type and the size is 0,
6297 * we'll use the system-wide default string
6298 * size. Note that we are _not_ looking at
6299 * the value of the DTRACEOPT_STRSIZE option;
6300 * had this been set, we would expect to have
6301 * a non-zero size value in the "pushtr".
6302 */
6303 tupregs[ttop].dttk_size =
6304 dtrace_strlen((char *)(uintptr_t)regs[rd],
6305 regs[r2] ? regs[r2] :
6306 dtrace_strsize_default) + 1;
6307 } else {
6308 if (regs[r2] > LONG_MAX) {
6309 *flags |= CPU_DTRACE_ILLOP;
6310 break;
6311 }
6312
6313 tupregs[ttop].dttk_size = regs[r2];
6314 }
6315
6316 tupregs[ttop++].dttk_value = regs[rd];
6317 break;
6318
6319 case DIF_OP_PUSHTV:
6320 if (ttop == DIF_DTR_NREGS) {
6321 *flags |= CPU_DTRACE_TUPOFLOW;
6322 break;
6323 }
6324
6325 tupregs[ttop].dttk_value = regs[rd];
6326 tupregs[ttop++].dttk_size = 0;
6327 break;
6328
6329 case DIF_OP_POPTS:
6330 if (ttop != 0)
6331 ttop--;
6332 break;
6333
6334 case DIF_OP_FLUSHTS:
6335 ttop = 0;
6336 break;
6337
6338 case DIF_OP_LDGAA:
6339 case DIF_OP_LDTAA: {
6340 dtrace_dynvar_t *dvar;
6341 dtrace_key_t *key = tupregs;
6342 uint_t nkeys = ttop;
6343
6344 id = DIF_INSTR_VAR(instr);
6345 ASSERT(id >= DIF_VAR_OTHER_UBASE);
6346 id -= DIF_VAR_OTHER_UBASE;
6347
6348 key[nkeys].dttk_value = (uint64_t)id;
6349 key[nkeys++].dttk_size = 0;
6350
6351 if (DIF_INSTR_OP(instr) == DIF_OP_LDTAA) {
6352 DTRACE_TLS_THRKEY(key[nkeys].dttk_value);
6353 key[nkeys++].dttk_size = 0;
6354 VERIFY(id < vstate->dtvs_ntlocals);
6355 v = &vstate->dtvs_tlocals[id];
6356 } else {
6357 VERIFY(id < vstate->dtvs_nglobals);
6358 v = &vstate->dtvs_globals[id]->dtsv_var;
6359 }
6360
6361 dvar = dtrace_dynvar(dstate, nkeys, key,
6362 v->dtdv_type.dtdt_size > sizeof (uint64_t) ?
6363 v->dtdv_type.dtdt_size : sizeof (uint64_t),
6364 DTRACE_DYNVAR_NOALLOC, mstate, vstate);
6365
6366 if (dvar == NULL) {
6367 regs[rd] = 0;
6368 break;
6369 }
6370
6371 if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) {
6372 regs[rd] = (uint64_t)(uintptr_t)dvar->dtdv_data;
6373 } else {
6374 regs[rd] = *((uint64_t *)dvar->dtdv_data);
6375 }
6376
6377 break;
6378 }
6379
6380 case DIF_OP_STGAA:
6381 case DIF_OP_STTAA: {
6382 dtrace_dynvar_t *dvar;
6383 dtrace_key_t *key = tupregs;
6384 uint_t nkeys = ttop;
6385
6386 id = DIF_INSTR_VAR(instr);
6387 ASSERT(id >= DIF_VAR_OTHER_UBASE);
6388 id -= DIF_VAR_OTHER_UBASE;
6389
6390 key[nkeys].dttk_value = (uint64_t)id;
6391 key[nkeys++].dttk_size = 0;
6392
6393 if (DIF_INSTR_OP(instr) == DIF_OP_STTAA) {
6394 DTRACE_TLS_THRKEY(key[nkeys].dttk_value);
6395 key[nkeys++].dttk_size = 0;
6396 VERIFY(id < vstate->dtvs_ntlocals);
6397 v = &vstate->dtvs_tlocals[id];
6398 } else {
6399 VERIFY(id < vstate->dtvs_nglobals);
6400 v = &vstate->dtvs_globals[id]->dtsv_var;
6401 }
6402
6403 dvar = dtrace_dynvar(dstate, nkeys, key,
6404 v->dtdv_type.dtdt_size > sizeof (uint64_t) ?
6405 v->dtdv_type.dtdt_size : sizeof (uint64_t),
6406 regs[rd] ? DTRACE_DYNVAR_ALLOC :
6407 DTRACE_DYNVAR_DEALLOC, mstate, vstate);
6408
6409 if (dvar == NULL)
6410 break;
6411
6412 if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) {
6413 size_t lim;
6414
6415 if (!dtrace_vcanload(
6416 (void *)(uintptr_t)regs[rd], &v->dtdv_type,
6417 &lim, mstate, vstate))
6418 break;
6419
6420 dtrace_vcopy((void *)(uintptr_t)regs[rd],
6421 dvar->dtdv_data, &v->dtdv_type, lim);
6422 } else {
6423 *((uint64_t *)dvar->dtdv_data) = regs[rd];
6424 }
6425
6426 break;
6427 }
6428
6429 case DIF_OP_ALLOCS: {
6430 uintptr_t ptr = P2ROUNDUP(mstate->dtms_scratch_ptr, 8);
6431 size_t size = ptr - mstate->dtms_scratch_ptr + regs[r1];
6432
6433 /*
6434 * Rounding up the user allocation size could have
6435 * overflowed large, bogus allocations (like -1ULL) to
6436 * 0.
6437 */
6438 if (size < regs[r1] ||
6439 !DTRACE_INSCRATCH(mstate, size)) {
6440 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
6441 regs[rd] = NULL;
6442 break;
6443 }
6444
6445 dtrace_bzero((void *) mstate->dtms_scratch_ptr, size);
6446 mstate->dtms_scratch_ptr += size;
6447 regs[rd] = ptr;
6448 break;
6449 }
6450
6451 case DIF_OP_COPYS:
6452 if (!dtrace_canstore(regs[rd], regs[r2],
6453 mstate, vstate)) {
6454 *flags |= CPU_DTRACE_BADADDR;
6455 *illval = regs[rd];
6456 break;
6457 }
6458
6459 if (!dtrace_canload(regs[r1], regs[r2], mstate, vstate))
6460 break;
6461
6462 dtrace_bcopy((void *)(uintptr_t)regs[r1],
6463 (void *)(uintptr_t)regs[rd], (size_t)regs[r2]);
6464 break;
6465
6466 case DIF_OP_STB:
6467 if (!dtrace_canstore(regs[rd], 1, mstate, vstate)) {
6468 *flags |= CPU_DTRACE_BADADDR;
6469 *illval = regs[rd];
6470 break;
6471 }
6472 *((uint8_t *)(uintptr_t)regs[rd]) = (uint8_t)regs[r1];
6473 break;
6474
6475 case DIF_OP_STH:
6476 if (!dtrace_canstore(regs[rd], 2, mstate, vstate)) {
6477 *flags |= CPU_DTRACE_BADADDR;
6478 *illval = regs[rd];
6479 break;
6480 }
6481 if (regs[rd] & 1) {
6482 *flags |= CPU_DTRACE_BADALIGN;
6483 *illval = regs[rd];
6484 break;
6485 }
6486 *((uint16_t *)(uintptr_t)regs[rd]) = (uint16_t)regs[r1];
6487 break;
6488
6489 case DIF_OP_STW:
6490 if (!dtrace_canstore(regs[rd], 4, mstate, vstate)) {
6491 *flags |= CPU_DTRACE_BADADDR;
6492 *illval = regs[rd];
6493 break;
6494 }
6495 if (regs[rd] & 3) {
6496 *flags |= CPU_DTRACE_BADALIGN;
6497 *illval = regs[rd];
6498 break;
6499 }
6500 *((uint32_t *)(uintptr_t)regs[rd]) = (uint32_t)regs[r1];
6501 break;
6502
6503 case DIF_OP_STX:
6504 if (!dtrace_canstore(regs[rd], 8, mstate, vstate)) {
6505 *flags |= CPU_DTRACE_BADADDR;
6506 *illval = regs[rd];
6507 break;
6508 }
6509 if (regs[rd] & 7) {
6510 *flags |= CPU_DTRACE_BADALIGN;
6511 *illval = regs[rd];
6512 break;
6513 }
6514 *((uint64_t *)(uintptr_t)regs[rd]) = regs[r1];
6515 break;
6516 }
6517 }
6518
6519 if (!(*flags & CPU_DTRACE_FAULT))
6520 return (rval);
6521
6522 mstate->dtms_fltoffs = opc * sizeof (dif_instr_t);
6523 mstate->dtms_present |= DTRACE_MSTATE_FLTOFFS;
6524
6525 return (0);
6526 }
6527
6528 static void
6529 dtrace_action_breakpoint(dtrace_ecb_t *ecb)
6530 {
6531 dtrace_probe_t *probe = ecb->dte_probe;
6532 dtrace_provider_t *prov = probe->dtpr_provider;
6533 char c[DTRACE_FULLNAMELEN + 80], *str;
6534 char *msg = "dtrace: breakpoint action at probe ";
6535 char *ecbmsg = " (ecb ";
6536 uintptr_t mask = (0xf << (sizeof (uintptr_t) * NBBY / 4));
6537 uintptr_t val = (uintptr_t)ecb;
6538 int shift = (sizeof (uintptr_t) * NBBY) - 4, i = 0;
6539
6540 if (dtrace_destructive_disallow)
6541 return;
6542
6543 /*
6544 * It's impossible to be taking action on the NULL probe.
6545 */
6546 ASSERT(probe != NULL);
6547
6548 /*
6549 * This is a poor man's (destitute man's?) sprintf(): we want to
6550 * print the provider name, module name, function name and name of
6551 * the probe, along with the hex address of the ECB with the breakpoint
6552 * action -- all of which we must place in the character buffer by
6553 * hand.
6554 */
6555 while (*msg != '\0')
6556 c[i++] = *msg++;
6557
6558 for (str = prov->dtpv_name; *str != '\0'; str++)
6559 c[i++] = *str;
6560 c[i++] = ':';
6561
6562 for (str = probe->dtpr_mod; *str != '\0'; str++)
6563 c[i++] = *str;
6564 c[i++] = ':';
6565
6566 for (str = probe->dtpr_func; *str != '\0'; str++)
6567 c[i++] = *str;
6568 c[i++] = ':';
6569
6570 for (str = probe->dtpr_name; *str != '\0'; str++)
6571 c[i++] = *str;
6572
6573 while (*ecbmsg != '\0')
6574 c[i++] = *ecbmsg++;
6575
6576 while (shift >= 0) {
6577 mask = (uintptr_t)0xf << shift;
6578
6579 if (val >= ((uintptr_t)1 << shift))
6580 c[i++] = "0123456789abcdef"[(val & mask) >> shift];
6581 shift -= 4;
6582 }
6583
6584 c[i++] = ')';
6585 c[i] = '\0';
6586
6587 debug_enter(c);
6588 }
6589
6590 static void
6591 dtrace_action_panic(dtrace_ecb_t *ecb)
6592 {
6593 dtrace_probe_t *probe = ecb->dte_probe;
6594
6595 /*
6596 * It's impossible to be taking action on the NULL probe.
6597 */
6598 ASSERT(probe != NULL);
6599
6600 if (dtrace_destructive_disallow)
6601 return;
6602
6603 if (dtrace_panicked != NULL)
6604 return;
6605
6606 if (dtrace_casptr(&dtrace_panicked, NULL, curthread) != NULL)
6607 return;
6608
6609 /*
6610 * We won the right to panic. (We want to be sure that only one
6611 * thread calls panic() from dtrace_probe(), and that panic() is
6612 * called exactly once.)
6613 */
6614 dtrace_panic("dtrace: panic action at probe %s:%s:%s:%s (ecb %p)",
6615 probe->dtpr_provider->dtpv_name, probe->dtpr_mod,
6616 probe->dtpr_func, probe->dtpr_name, (void *)ecb);
6617 }
6618
6619 static void
6620 dtrace_action_raise(uint64_t sig)
6621 {
6622 if (dtrace_destructive_disallow)
6623 return;
6624
6625 if (sig >= NSIG) {
6626 DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP);
6627 return;
6628 }
6629
6630 /*
6631 * raise() has a queue depth of 1 -- we ignore all subsequent
6632 * invocations of the raise() action.
6633 */
6634 if (curthread->t_dtrace_sig == 0)
6635 curthread->t_dtrace_sig = (uint8_t)sig;
6636
6637 curthread->t_sig_check = 1;
6638 aston(curthread);
6639 }
6640
6641 static void
6642 dtrace_action_stop(void)
6643 {
6644 if (dtrace_destructive_disallow)
6645 return;
6646
6647 if (!curthread->t_dtrace_stop) {
6648 curthread->t_dtrace_stop = 1;
6649 curthread->t_sig_check = 1;
6650 aston(curthread);
6651 }
6652 }
6653
6654 static void
6655 dtrace_action_chill(dtrace_mstate_t *mstate, hrtime_t val)
6656 {
6657 hrtime_t now;
6658 volatile uint16_t *flags;
6659 cpu_t *cpu = CPU;
6660
6661 if (dtrace_destructive_disallow)
6662 return;
6663
6664 flags = (volatile uint16_t *)&cpu_core[cpu->cpu_id].cpuc_dtrace_flags;
6665
6666 now = dtrace_gethrtime();
6667
6668 if (now - cpu->cpu_dtrace_chillmark > dtrace_chill_interval) {
6669 /*
6670 * We need to advance the mark to the current time.
6671 */
6672 cpu->cpu_dtrace_chillmark = now;
6673 cpu->cpu_dtrace_chilled = 0;
6674 }
6675
6676 /*
6677 * Now check to see if the requested chill time would take us over
6678 * the maximum amount of time allowed in the chill interval. (Or
6679 * worse, if the calculation itself induces overflow.)
6680 */
6681 if (cpu->cpu_dtrace_chilled + val > dtrace_chill_max ||
6682 cpu->cpu_dtrace_chilled + val < cpu->cpu_dtrace_chilled) {
6683 *flags |= CPU_DTRACE_ILLOP;
6684 return;
6685 }
6686
6687 while (dtrace_gethrtime() - now < val)
6688 continue;
6689
6690 /*
6691 * Normally, we assure that the value of the variable "timestamp" does
6692 * not change within an ECB. The presence of chill() represents an
6693 * exception to this rule, however.
6694 */
6695 mstate->dtms_present &= ~DTRACE_MSTATE_TIMESTAMP;
6696 cpu->cpu_dtrace_chilled += val;
6697 }
6698
6699 static void
6700 dtrace_action_ustack(dtrace_mstate_t *mstate, dtrace_state_t *state,
6701 uint64_t *buf, uint64_t arg)
6702 {
6703 int nframes = DTRACE_USTACK_NFRAMES(arg);
6704 int strsize = DTRACE_USTACK_STRSIZE(arg);
6705 uint64_t *pcs = &buf[1], *fps;
6706 char *str = (char *)&pcs[nframes];
6707 int size, offs = 0, i, j;
6708 size_t rem;
6709 uintptr_t old = mstate->dtms_scratch_ptr, saved;
6710 uint16_t *flags = &cpu_core[CPU->cpu_id].cpuc_dtrace_flags;
6711 char *sym;
6712
6713 /*
6714 * Should be taking a faster path if string space has not been
6715 * allocated.
6716 */
6717 ASSERT(strsize != 0);
6718
6719 /*
6720 * We will first allocate some temporary space for the frame pointers.
6721 */
6722 fps = (uint64_t *)P2ROUNDUP(mstate->dtms_scratch_ptr, 8);
6723 size = (uintptr_t)fps - mstate->dtms_scratch_ptr +
6724 (nframes * sizeof (uint64_t));
6725
6726 if (!DTRACE_INSCRATCH(mstate, size)) {
6727 /*
6728 * Not enough room for our frame pointers -- need to indicate
6729 * that we ran out of scratch space.
6730 */
6731 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
6732 return;
6733 }
6734
6735 mstate->dtms_scratch_ptr += size;
6736 saved = mstate->dtms_scratch_ptr;
6737
6738 /*
6739 * Now get a stack with both program counters and frame pointers.
6740 */
6741 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
6742 dtrace_getufpstack(buf, fps, nframes + 1);
6743 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
6744
6745 /*
6746 * If that faulted, we're cooked.
6747 */
6748 if (*flags & CPU_DTRACE_FAULT)
6749 goto out;
6750
6751 /*
6752 * Now we want to walk up the stack, calling the USTACK helper. For
6753 * each iteration, we restore the scratch pointer.
6754 */
6755 for (i = 0; i < nframes; i++) {
6756 mstate->dtms_scratch_ptr = saved;
6757
6758 if (offs >= strsize)
6759 break;
6760
6761 sym = (char *)(uintptr_t)dtrace_helper(
6762 DTRACE_HELPER_ACTION_USTACK,
6763 mstate, state, pcs[i], fps[i]);
6764
6765 /*
6766 * If we faulted while running the helper, we're going to
6767 * clear the fault and null out the corresponding string.
6768 */
6769 if (*flags & CPU_DTRACE_FAULT) {
6770 *flags &= ~CPU_DTRACE_FAULT;
6771 str[offs++] = '\0';
6772 continue;
6773 }
6774
6775 if (sym == NULL) {
6776 str[offs++] = '\0';
6777 continue;
6778 }
6779
6780 if (!dtrace_strcanload((uintptr_t)sym, strsize, &rem, mstate,
6781 &(state->dts_vstate))) {
6782 str[offs++] = '\0';
6783 continue;
6784 }
6785
6786 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
6787
6788 /*
6789 * Now copy in the string that the helper returned to us.
6790 */
6791 for (j = 0; offs + j < strsize && j < rem; j++) {
6792 if ((str[offs + j] = sym[j]) == '\0')
6793 break;
6794 }
6795
6796 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
6797
6798 offs += j + 1;
6799 }
6800
6801 if (offs >= strsize) {
6802 /*
6803 * If we didn't have room for all of the strings, we don't
6804 * abort processing -- this needn't be a fatal error -- but we
6805 * still want to increment a counter (dts_stkstroverflows) to
6806 * allow this condition to be warned about. (If this is from
6807 * a jstack() action, it is easily tuned via jstackstrsize.)
6808 */
6809 dtrace_error(&state->dts_stkstroverflows);
6810 }
6811
6812 while (offs < strsize)
6813 str[offs++] = '\0';
6814
6815 out:
6816 mstate->dtms_scratch_ptr = old;
6817 }
6818
6819 static void
6820 dtrace_store_by_ref(dtrace_difo_t *dp, caddr_t tomax, size_t size,
6821 size_t *valoffsp, uint64_t *valp, uint64_t end, int intuple, int dtkind)
6822 {
6823 volatile uint16_t *flags;
6824 uint64_t val = *valp;
6825 size_t valoffs = *valoffsp;
6826
6827 flags = (volatile uint16_t *)&cpu_core[CPU->cpu_id].cpuc_dtrace_flags;
6828 ASSERT(dtkind == DIF_TF_BYREF || dtkind == DIF_TF_BYUREF);
6829
6830 /*
6831 * If this is a string, we're going to only load until we find the zero
6832 * byte -- after which we'll store zero bytes.
6833 */
6834 if (dp->dtdo_rtype.dtdt_kind == DIF_TYPE_STRING) {
6835 char c = '\0' + 1;
6836 size_t s;
6837
6838 for (s = 0; s < size; s++) {
6839 if (c != '\0' && dtkind == DIF_TF_BYREF) {
6840 c = dtrace_load8(val++);
6841 } else if (c != '\0' && dtkind == DIF_TF_BYUREF) {
6842 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
6843 c = dtrace_fuword8((void *)(uintptr_t)val++);
6844 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
6845 if (*flags & CPU_DTRACE_FAULT)
6846 break;
6847 }
6848
6849 DTRACE_STORE(uint8_t, tomax, valoffs++, c);
6850
6851 if (c == '\0' && intuple)
6852 break;
6853 }
6854 } else {
6855 uint8_t c;
6856 while (valoffs < end) {
6857 if (dtkind == DIF_TF_BYREF) {
6858 c = dtrace_load8(val++);
6859 } else if (dtkind == DIF_TF_BYUREF) {
6860 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
6861 c = dtrace_fuword8((void *)(uintptr_t)val++);
6862 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
6863 if (*flags & CPU_DTRACE_FAULT)
6864 break;
6865 }
6866
6867 DTRACE_STORE(uint8_t, tomax,
6868 valoffs++, c);
6869 }
6870 }
6871
6872 *valp = val;
6873 *valoffsp = valoffs;
6874 }
6875
6876 /*
6877 * If you're looking for the epicenter of DTrace, you just found it. This
6878 * is the function called by the provider to fire a probe -- from which all
6879 * subsequent probe-context DTrace activity emanates.
6880 */
6881 void
6882 dtrace_probe(dtrace_id_t id, uintptr_t arg0, uintptr_t arg1,
6883 uintptr_t arg2, uintptr_t arg3, uintptr_t arg4)
6884 {
6885 processorid_t cpuid;
6886 dtrace_icookie_t cookie;
6887 dtrace_probe_t *probe;
6888 dtrace_mstate_t mstate;
6889 dtrace_ecb_t *ecb;
6890 dtrace_action_t *act;
6891 intptr_t offs;
6892 size_t size;
6893 int vtime, onintr;
6894 volatile uint16_t *flags;
6895 hrtime_t now, end;
6896
6897 /*
6898 * Kick out immediately if this CPU is still being born (in which case
6899 * curthread will be set to -1) or the current thread can't allow
6900 * probes in its current context.
6901 */
6902 if (((uintptr_t)curthread & 1) || (curthread->t_flag & T_DONTDTRACE))
6903 return;
6904
6905 cookie = dtrace_interrupt_disable();
6906 probe = dtrace_probes[id - 1];
6907 cpuid = CPU->cpu_id;
6908 onintr = CPU_ON_INTR(CPU);
6909
6910 CPU->cpu_dtrace_probes++;
6911
6912 if (!onintr && probe->dtpr_predcache != DTRACE_CACHEIDNONE &&
6913 probe->dtpr_predcache == curthread->t_predcache) {
6914 /*
6915 * We have hit in the predicate cache; we know that
6916 * this predicate would evaluate to be false.
6917 */
6918 dtrace_interrupt_enable(cookie);
6919 return;
6920 }
6921
6922 if (panic_quiesce) {
6923 /*
6924 * We don't trace anything if we're panicking.
6925 */
6926 dtrace_interrupt_enable(cookie);
6927 return;
6928 }
6929
6930 now = mstate.dtms_timestamp = dtrace_gethrtime();
6931 mstate.dtms_present |= DTRACE_MSTATE_TIMESTAMP;
6932 vtime = dtrace_vtime_references != 0;
6933
6934 if (vtime && curthread->t_dtrace_start)
6935 curthread->t_dtrace_vtime += now - curthread->t_dtrace_start;
6936
6937 mstate.dtms_difo = NULL;
6938 mstate.dtms_probe = probe;
6939 mstate.dtms_strtok = NULL;
6940 mstate.dtms_arg[0] = arg0;
6941 mstate.dtms_arg[1] = arg1;
6942 mstate.dtms_arg[2] = arg2;
6943 mstate.dtms_arg[3] = arg3;
6944 mstate.dtms_arg[4] = arg4;
6945
6946 flags = (volatile uint16_t *)&cpu_core[cpuid].cpuc_dtrace_flags;
6947
6948 for (ecb = probe->dtpr_ecb; ecb != NULL; ecb = ecb->dte_next) {
6949 dtrace_predicate_t *pred = ecb->dte_predicate;
6950 dtrace_state_t *state = ecb->dte_state;
6951 dtrace_buffer_t *buf = &state->dts_buffer[cpuid];
6952 dtrace_buffer_t *aggbuf = &state->dts_aggbuffer[cpuid];
6953 dtrace_vstate_t *vstate = &state->dts_vstate;
6954 dtrace_provider_t *prov = probe->dtpr_provider;
6955 uint64_t tracememsize = 0;
6956 int committed = 0;
6957 caddr_t tomax;
6958
6959 /*
6960 * A little subtlety with the following (seemingly innocuous)
6961 * declaration of the automatic 'val': by looking at the
6962 * code, you might think that it could be declared in the
6963 * action processing loop, below. (That is, it's only used in
6964 * the action processing loop.) However, it must be declared
6965 * out of that scope because in the case of DIF expression
6966 * arguments to aggregating actions, one iteration of the
6967 * action loop will use the last iteration's value.
6968 */
6969 #ifdef lint
6970 uint64_t val = 0;
6971 #else
6972 uint64_t val;
6973 #endif
6974
6975 mstate.dtms_present = DTRACE_MSTATE_ARGS | DTRACE_MSTATE_PROBE;
6976 mstate.dtms_access = DTRACE_ACCESS_ARGS | DTRACE_ACCESS_PROC;
6977 mstate.dtms_getf = NULL;
6978
6979 *flags &= ~CPU_DTRACE_ERROR;
6980
6981 if (prov == dtrace_provider) {
6982 /*
6983 * If dtrace itself is the provider of this probe,
6984 * we're only going to continue processing the ECB if
6985 * arg0 (the dtrace_state_t) is equal to the ECB's
6986 * creating state. (This prevents disjoint consumers
6987 * from seeing one another's metaprobes.)
6988 */
6989 if (arg0 != (uint64_t)(uintptr_t)state)
6990 continue;
6991 }
6992
6993 if (state->dts_activity != DTRACE_ACTIVITY_ACTIVE) {
6994 /*
6995 * We're not currently active. If our provider isn't
6996 * the dtrace pseudo provider, we're not interested.
6997 */
6998 if (prov != dtrace_provider)
6999 continue;
7000
7001 /*
7002 * Now we must further check if we are in the BEGIN
7003 * probe. If we are, we will only continue processing
7004 * if we're still in WARMUP -- if one BEGIN enabling
7005 * has invoked the exit() action, we don't want to
7006 * evaluate subsequent BEGIN enablings.
7007 */
7008 if (probe->dtpr_id == dtrace_probeid_begin &&
7009 state->dts_activity != DTRACE_ACTIVITY_WARMUP) {
7010 ASSERT(state->dts_activity ==
7011 DTRACE_ACTIVITY_DRAINING);
7012 continue;
7013 }
7014 }
7015
7016 if (ecb->dte_cond && !dtrace_priv_probe(state, &mstate, ecb))
7017 continue;
7018
7019 if (now - state->dts_alive > dtrace_deadman_timeout) {
7020 /*
7021 * We seem to be dead. Unless we (a) have kernel
7022 * destructive permissions (b) have explicitly enabled
7023 * destructive actions and (c) destructive actions have
7024 * not been disabled, we're going to transition into
7025 * the KILLED state, from which no further processing
7026 * on this state will be performed.
7027 */
7028 if (!dtrace_priv_kernel_destructive(state) ||
7029 !state->dts_cred.dcr_destructive ||
7030 dtrace_destructive_disallow) {
7031 void *activity = &state->dts_activity;
7032 dtrace_activity_t current;
7033
7034 do {
7035 current = state->dts_activity;
7036 } while (dtrace_cas32(activity, current,
7037 DTRACE_ACTIVITY_KILLED) != current);
7038
7039 continue;
7040 }
7041 }
7042
7043 if ((offs = dtrace_buffer_reserve(buf, ecb->dte_needed,
7044 ecb->dte_alignment, state, &mstate)) < 0)
7045 continue;
7046
7047 tomax = buf->dtb_tomax;
7048 ASSERT(tomax != NULL);
7049
7050 if (ecb->dte_size != 0) {
7051 dtrace_rechdr_t dtrh;
7052 if (!(mstate.dtms_present & DTRACE_MSTATE_TIMESTAMP)) {
7053 mstate.dtms_timestamp = dtrace_gethrtime();
7054 mstate.dtms_present |= DTRACE_MSTATE_TIMESTAMP;
7055 }
7056 ASSERT3U(ecb->dte_size, >=, sizeof (dtrace_rechdr_t));
7057 dtrh.dtrh_epid = ecb->dte_epid;
7058 DTRACE_RECORD_STORE_TIMESTAMP(&dtrh,
7059 mstate.dtms_timestamp);
7060 *((dtrace_rechdr_t *)(tomax + offs)) = dtrh;
7061 }
7062
7063 mstate.dtms_epid = ecb->dte_epid;
7064 mstate.dtms_present |= DTRACE_MSTATE_EPID;
7065
7066 if (state->dts_cred.dcr_visible & DTRACE_CRV_KERNEL)
7067 mstate.dtms_access |= DTRACE_ACCESS_KERNEL;
7068
7069 if (pred != NULL) {
7070 dtrace_difo_t *dp = pred->dtp_difo;
7071 int rval;
7072
7073 rval = dtrace_dif_emulate(dp, &mstate, vstate, state);
7074
7075 if (!(*flags & CPU_DTRACE_ERROR) && !rval) {
7076 dtrace_cacheid_t cid = probe->dtpr_predcache;
7077
7078 if (cid != DTRACE_CACHEIDNONE && !onintr) {
7079 /*
7080 * Update the predicate cache...
7081 */
7082 ASSERT(cid == pred->dtp_cacheid);
7083 curthread->t_predcache = cid;
7084 }
7085
7086 continue;
7087 }
7088 }
7089
7090 for (act = ecb->dte_action; !(*flags & CPU_DTRACE_ERROR) &&
7091 act != NULL; act = act->dta_next) {
7092 size_t valoffs;
7093 dtrace_difo_t *dp;
7094 dtrace_recdesc_t *rec = &act->dta_rec;
7095
7096 size = rec->dtrd_size;
7097 valoffs = offs + rec->dtrd_offset;
7098
7099 if (DTRACEACT_ISAGG(act->dta_kind)) {
7100 uint64_t v = 0xbad;
7101 dtrace_aggregation_t *agg;
7102
7103 agg = (dtrace_aggregation_t *)act;
7104
7105 if ((dp = act->dta_difo) != NULL)
7106 v = dtrace_dif_emulate(dp,
7107 &mstate, vstate, state);
7108
7109 if (*flags & CPU_DTRACE_ERROR)
7110 continue;
7111
7112 /*
7113 * Note that we always pass the expression
7114 * value from the previous iteration of the
7115 * action loop. This value will only be used
7116 * if there is an expression argument to the
7117 * aggregating action, denoted by the
7118 * dtag_hasarg field.
7119 */
7120 dtrace_aggregate(agg, buf,
7121 offs, aggbuf, v, val);
7122 continue;
7123 }
7124
7125 switch (act->dta_kind) {
7126 case DTRACEACT_STOP:
7127 if (dtrace_priv_proc_destructive(state,
7128 &mstate))
7129 dtrace_action_stop();
7130 continue;
7131
7132 case DTRACEACT_BREAKPOINT:
7133 if (dtrace_priv_kernel_destructive(state))
7134 dtrace_action_breakpoint(ecb);
7135 continue;
7136
7137 case DTRACEACT_PANIC:
7138 if (dtrace_priv_kernel_destructive(state))
7139 dtrace_action_panic(ecb);
7140 continue;
7141
7142 case DTRACEACT_STACK:
7143 if (!dtrace_priv_kernel(state))
7144 continue;
7145
7146 dtrace_getpcstack((pc_t *)(tomax + valoffs),
7147 size / sizeof (pc_t), probe->dtpr_aframes,
7148 DTRACE_ANCHORED(probe) ? NULL :
7149 (uint32_t *)arg0);
7150
7151 continue;
7152
7153 case DTRACEACT_JSTACK:
7154 case DTRACEACT_USTACK:
7155 if (!dtrace_priv_proc(state, &mstate))
7156 continue;
7157
7158 /*
7159 * See comment in DIF_VAR_PID.
7160 */
7161 if (DTRACE_ANCHORED(mstate.dtms_probe) &&
7162 CPU_ON_INTR(CPU)) {
7163 int depth = DTRACE_USTACK_NFRAMES(
7164 rec->dtrd_arg) + 1;
7165
7166 dtrace_bzero((void *)(tomax + valoffs),
7167 DTRACE_USTACK_STRSIZE(rec->dtrd_arg)
7168 + depth * sizeof (uint64_t));
7169
7170 continue;
7171 }
7172
7173 if (DTRACE_USTACK_STRSIZE(rec->dtrd_arg) != 0 &&
7174 curproc->p_dtrace_helpers != NULL) {
7175 /*
7176 * This is the slow path -- we have
7177 * allocated string space, and we're
7178 * getting the stack of a process that
7179 * has helpers. Call into a separate
7180 * routine to perform this processing.
7181 */
7182 dtrace_action_ustack(&mstate, state,
7183 (uint64_t *)(tomax + valoffs),
7184 rec->dtrd_arg);
7185 continue;
7186 }
7187
7188 /*
7189 * Clear the string space, since there's no
7190 * helper to do it for us.
7191 */
7192 if (DTRACE_USTACK_STRSIZE(rec->dtrd_arg) != 0) {
7193 int depth = DTRACE_USTACK_NFRAMES(
7194 rec->dtrd_arg);
7195 size_t strsize = DTRACE_USTACK_STRSIZE(
7196 rec->dtrd_arg);
7197 uint64_t *buf = (uint64_t *)(tomax +
7198 valoffs);
7199 void *strspace = &buf[depth + 1];
7200
7201 dtrace_bzero(strspace,
7202 MIN(depth, strsize));
7203 }
7204
7205 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
7206 dtrace_getupcstack((uint64_t *)
7207 (tomax + valoffs),
7208 DTRACE_USTACK_NFRAMES(rec->dtrd_arg) + 1);
7209 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
7210 continue;
7211
7212 default:
7213 break;
7214 }
7215
7216 dp = act->dta_difo;
7217 ASSERT(dp != NULL);
7218
7219 val = dtrace_dif_emulate(dp, &mstate, vstate, state);
7220
7221 if (*flags & CPU_DTRACE_ERROR)
7222 continue;
7223
7224 switch (act->dta_kind) {
7225 case DTRACEACT_SPECULATE: {
7226 dtrace_rechdr_t *dtrh;
7227
7228 ASSERT(buf == &state->dts_buffer[cpuid]);
7229 buf = dtrace_speculation_buffer(state,
7230 cpuid, val);
7231
7232 if (buf == NULL) {
7233 *flags |= CPU_DTRACE_DROP;
7234 continue;
7235 }
7236
7237 offs = dtrace_buffer_reserve(buf,
7238 ecb->dte_needed, ecb->dte_alignment,
7239 state, NULL);
7240
7241 if (offs < 0) {
7242 *flags |= CPU_DTRACE_DROP;
7243 continue;
7244 }
7245
7246 tomax = buf->dtb_tomax;
7247 ASSERT(tomax != NULL);
7248
7249 if (ecb->dte_size == 0)
7250 continue;
7251
7252 ASSERT3U(ecb->dte_size, >=,
7253 sizeof (dtrace_rechdr_t));
7254 dtrh = ((void *)(tomax + offs));
7255 dtrh->dtrh_epid = ecb->dte_epid;
7256 /*
7257 * When the speculation is committed, all of
7258 * the records in the speculative buffer will
7259 * have their timestamps set to the commit
7260 * time. Until then, it is set to a sentinel
7261 * value, for debugability.
7262 */
7263 DTRACE_RECORD_STORE_TIMESTAMP(dtrh, UINT64_MAX);
7264 continue;
7265 }
7266
7267 case DTRACEACT_CHILL:
7268 if (dtrace_priv_kernel_destructive(state))
7269 dtrace_action_chill(&mstate, val);
7270 continue;
7271
7272 case DTRACEACT_RAISE:
7273 if (dtrace_priv_proc_destructive(state,
7274 &mstate))
7275 dtrace_action_raise(val);
7276 continue;
7277
7278 case DTRACEACT_COMMIT:
7279 ASSERT(!committed);
7280
7281 /*
7282 * We need to commit our buffer state.
7283 */
7284 if (ecb->dte_size)
7285 buf->dtb_offset = offs + ecb->dte_size;
7286 buf = &state->dts_buffer[cpuid];
7287 dtrace_speculation_commit(state, cpuid, val);
7288 committed = 1;
7289 continue;
7290
7291 case DTRACEACT_DISCARD:
7292 dtrace_speculation_discard(state, cpuid, val);
7293 continue;
7294
7295 case DTRACEACT_DIFEXPR:
7296 case DTRACEACT_LIBACT:
7297 case DTRACEACT_PRINTF:
7298 case DTRACEACT_PRINTA:
7299 case DTRACEACT_SYSTEM:
7300 case DTRACEACT_FREOPEN:
7301 case DTRACEACT_TRACEMEM:
7302 break;
7303
7304 case DTRACEACT_TRACEMEM_DYNSIZE:
7305 tracememsize = val;
7306 break;
7307
7308 case DTRACEACT_SYM:
7309 case DTRACEACT_MOD:
7310 if (!dtrace_priv_kernel(state))
7311 continue;
7312 break;
7313
7314 case DTRACEACT_USYM:
7315 case DTRACEACT_UMOD:
7316 case DTRACEACT_UADDR: {
7317 struct pid *pid = curthread->t_procp->p_pidp;
7318
7319 if (!dtrace_priv_proc(state, &mstate))
7320 continue;
7321
7322 DTRACE_STORE(uint64_t, tomax,
7323 valoffs, (uint64_t)pid->pid_id);
7324 DTRACE_STORE(uint64_t, tomax,
7325 valoffs + sizeof (uint64_t), val);
7326
7327 continue;
7328 }
7329
7330 case DTRACEACT_EXIT: {
7331 /*
7332 * For the exit action, we are going to attempt
7333 * to atomically set our activity to be
7334 * draining. If this fails (either because
7335 * another CPU has beat us to the exit action,
7336 * or because our current activity is something
7337 * other than ACTIVE or WARMUP), we will
7338 * continue. This assures that the exit action
7339 * can be successfully recorded at most once
7340 * when we're in the ACTIVE state. If we're
7341 * encountering the exit() action while in
7342 * COOLDOWN, however, we want to honor the new
7343 * status code. (We know that we're the only
7344 * thread in COOLDOWN, so there is no race.)
7345 */
7346 void *activity = &state->dts_activity;
7347 dtrace_activity_t current = state->dts_activity;
7348
7349 if (current == DTRACE_ACTIVITY_COOLDOWN)
7350 break;
7351
7352 if (current != DTRACE_ACTIVITY_WARMUP)
7353 current = DTRACE_ACTIVITY_ACTIVE;
7354
7355 if (dtrace_cas32(activity, current,
7356 DTRACE_ACTIVITY_DRAINING) != current) {
7357 *flags |= CPU_DTRACE_DROP;
7358 continue;
7359 }
7360
7361 break;
7362 }
7363
7364 default:
7365 ASSERT(0);
7366 }
7367
7368 if (dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF ||
7369 dp->dtdo_rtype.dtdt_flags & DIF_TF_BYUREF) {
7370 uintptr_t end = valoffs + size;
7371
7372 if (tracememsize != 0 &&
7373 valoffs + tracememsize < end) {
7374 end = valoffs + tracememsize;
7375 tracememsize = 0;
7376 }
7377
7378 if (dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF &&
7379 !dtrace_vcanload((void *)(uintptr_t)val,
7380 &dp->dtdo_rtype, NULL, &mstate, vstate))
7381 continue;
7382
7383 dtrace_store_by_ref(dp, tomax, size, &valoffs,
7384 &val, end, act->dta_intuple,
7385 dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF ?
7386 DIF_TF_BYREF: DIF_TF_BYUREF);
7387 continue;
7388 }
7389
7390 switch (size) {
7391 case 0:
7392 break;
7393
7394 case sizeof (uint8_t):
7395 DTRACE_STORE(uint8_t, tomax, valoffs, val);
7396 break;
7397 case sizeof (uint16_t):
7398 DTRACE_STORE(uint16_t, tomax, valoffs, val);
7399 break;
7400 case sizeof (uint32_t):
7401 DTRACE_STORE(uint32_t, tomax, valoffs, val);
7402 break;
7403 case sizeof (uint64_t):
7404 DTRACE_STORE(uint64_t, tomax, valoffs, val);
7405 break;
7406 default:
7407 /*
7408 * Any other size should have been returned by
7409 * reference, not by value.
7410 */
7411 ASSERT(0);
7412 break;
7413 }
7414 }
7415
7416 if (*flags & CPU_DTRACE_DROP)
7417 continue;
7418
7419 if (*flags & CPU_DTRACE_FAULT) {
7420 int ndx;
7421 dtrace_action_t *err;
7422
7423 buf->dtb_errors++;
7424
7425 if (probe->dtpr_id == dtrace_probeid_error) {
7426 /*
7427 * There's nothing we can do -- we had an
7428 * error on the error probe. We bump an
7429 * error counter to at least indicate that
7430 * this condition happened.
7431 */
7432 dtrace_error(&state->dts_dblerrors);
7433 continue;
7434 }
7435
7436 if (vtime) {
7437 /*
7438 * Before recursing on dtrace_probe(), we
7439 * need to explicitly clear out our start
7440 * time to prevent it from being accumulated
7441 * into t_dtrace_vtime.
7442 */
7443 curthread->t_dtrace_start = 0;
7444 }
7445
7446 /*
7447 * Iterate over the actions to figure out which action
7448 * we were processing when we experienced the error.
7449 * Note that act points _past_ the faulting action; if
7450 * act is ecb->dte_action, the fault was in the
7451 * predicate, if it's ecb->dte_action->dta_next it's
7452 * in action #1, and so on.
7453 */
7454 for (err = ecb->dte_action, ndx = 0;
7455 err != act; err = err->dta_next, ndx++)
7456 continue;
7457
7458 dtrace_probe_error(state, ecb->dte_epid, ndx,
7459 (mstate.dtms_present & DTRACE_MSTATE_FLTOFFS) ?
7460 mstate.dtms_fltoffs : -1, DTRACE_FLAGS2FLT(*flags),
7461 cpu_core[cpuid].cpuc_dtrace_illval);
7462
7463 continue;
7464 }
7465
7466 if (!committed)
7467 buf->dtb_offset = offs + ecb->dte_size;
7468 }
7469
7470 end = dtrace_gethrtime();
7471 if (vtime)
7472 curthread->t_dtrace_start = end;
7473
7474 CPU->cpu_dtrace_nsec += end - now;
7475
7476 dtrace_interrupt_enable(cookie);
7477 }
7478
7479 /*
7480 * DTrace Probe Hashing Functions
7481 *
7482 * The functions in this section (and indeed, the functions in remaining
7483 * sections) are not _called_ from probe context. (Any exceptions to this are
7484 * marked with a "Note:".) Rather, they are called from elsewhere in the
7485 * DTrace framework to look-up probes in, add probes to and remove probes from
7486 * the DTrace probe hashes. (Each probe is hashed by each element of the
7487 * probe tuple -- allowing for fast lookups, regardless of what was
7488 * specified.)
7489 */
7490 static uint_t
7491 dtrace_hash_str(char *p)
7492 {
7493 unsigned int g;
7494 uint_t hval = 0;
7495
7496 while (*p) {
7497 hval = (hval << 4) + *p++;
7498 if ((g = (hval & 0xf0000000)) != 0)
7499 hval ^= g >> 24;
7500 hval &= ~g;
7501 }
7502 return (hval);
7503 }
7504
7505 static dtrace_hash_t *
7506 dtrace_hash_create(uintptr_t stroffs, uintptr_t nextoffs, uintptr_t prevoffs)
7507 {
7508 dtrace_hash_t *hash = kmem_zalloc(sizeof (dtrace_hash_t), KM_SLEEP);
7509
7510 hash->dth_stroffs = stroffs;
7511 hash->dth_nextoffs = nextoffs;
7512 hash->dth_prevoffs = prevoffs;
7513
7514 hash->dth_size = 1;
7515 hash->dth_mask = hash->dth_size - 1;
7516
7517 hash->dth_tab = kmem_zalloc(hash->dth_size *
7518 sizeof (dtrace_hashbucket_t *), KM_SLEEP);
7519
7520 return (hash);
7521 }
7522
7523 static void
7524 dtrace_hash_destroy(dtrace_hash_t *hash)
7525 {
7526 #ifdef DEBUG
7527 int i;
7528
7529 for (i = 0; i < hash->dth_size; i++)
7530 ASSERT(hash->dth_tab[i] == NULL);
7531 #endif
7532
7533 kmem_free(hash->dth_tab,
7534 hash->dth_size * sizeof (dtrace_hashbucket_t *));
7535 kmem_free(hash, sizeof (dtrace_hash_t));
7536 }
7537
7538 static void
7539 dtrace_hash_resize(dtrace_hash_t *hash)
7540 {
7541 int size = hash->dth_size, i, ndx;
7542 int new_size = hash->dth_size << 1;
7543 int new_mask = new_size - 1;
7544 dtrace_hashbucket_t **new_tab, *bucket, *next;
7545
7546 ASSERT((new_size & new_mask) == 0);
7547
7548 new_tab = kmem_zalloc(new_size * sizeof (void *), KM_SLEEP);
7549
7550 for (i = 0; i < size; i++) {
7551 for (bucket = hash->dth_tab[i]; bucket != NULL; bucket = next) {
7552 dtrace_probe_t *probe = bucket->dthb_chain;
7553
7554 ASSERT(probe != NULL);
7555 ndx = DTRACE_HASHSTR(hash, probe) & new_mask;
7556
7557 next = bucket->dthb_next;
7558 bucket->dthb_next = new_tab[ndx];
7559 new_tab[ndx] = bucket;
7560 }
7561 }
7562
7563 kmem_free(hash->dth_tab, hash->dth_size * sizeof (void *));
7564 hash->dth_tab = new_tab;
7565 hash->dth_size = new_size;
7566 hash->dth_mask = new_mask;
7567 }
7568
7569 static void
7570 dtrace_hash_add(dtrace_hash_t *hash, dtrace_probe_t *new)
7571 {
7572 int hashval = DTRACE_HASHSTR(hash, new);
7573 int ndx = hashval & hash->dth_mask;
7574 dtrace_hashbucket_t *bucket = hash->dth_tab[ndx];
7575 dtrace_probe_t **nextp, **prevp;
7576
7577 for (; bucket != NULL; bucket = bucket->dthb_next) {
7578 if (DTRACE_HASHEQ(hash, bucket->dthb_chain, new))
7579 goto add;
7580 }
7581
7582 if ((hash->dth_nbuckets >> 1) > hash->dth_size) {
7583 dtrace_hash_resize(hash);
7584 dtrace_hash_add(hash, new);
7585 return;
7586 }
7587
7588 bucket = kmem_zalloc(sizeof (dtrace_hashbucket_t), KM_SLEEP);
7589 bucket->dthb_next = hash->dth_tab[ndx];
7590 hash->dth_tab[ndx] = bucket;
7591 hash->dth_nbuckets++;
7592
7593 add:
7594 nextp = DTRACE_HASHNEXT(hash, new);
7595 ASSERT(*nextp == NULL && *(DTRACE_HASHPREV(hash, new)) == NULL);
7596 *nextp = bucket->dthb_chain;
7597
7598 if (bucket->dthb_chain != NULL) {
7599 prevp = DTRACE_HASHPREV(hash, bucket->dthb_chain);
7600 ASSERT(*prevp == NULL);
7601 *prevp = new;
7602 }
7603
7604 bucket->dthb_chain = new;
7605 bucket->dthb_len++;
7606 }
7607
7608 static dtrace_probe_t *
7609 dtrace_hash_lookup(dtrace_hash_t *hash, dtrace_probe_t *template)
7610 {
7611 int hashval = DTRACE_HASHSTR(hash, template);
7612 int ndx = hashval & hash->dth_mask;
7613 dtrace_hashbucket_t *bucket = hash->dth_tab[ndx];
7614
7615 for (; bucket != NULL; bucket = bucket->dthb_next) {
7616 if (DTRACE_HASHEQ(hash, bucket->dthb_chain, template))
7617 return (bucket->dthb_chain);
7618 }
7619
7620 return (NULL);
7621 }
7622
7623 static int
7624 dtrace_hash_collisions(dtrace_hash_t *hash, dtrace_probe_t *template)
7625 {
7626 int hashval = DTRACE_HASHSTR(hash, template);
7627 int ndx = hashval & hash->dth_mask;
7628 dtrace_hashbucket_t *bucket = hash->dth_tab[ndx];
7629
7630 for (; bucket != NULL; bucket = bucket->dthb_next) {
7631 if (DTRACE_HASHEQ(hash, bucket->dthb_chain, template))
7632 return (bucket->dthb_len);
7633 }
7634
7635 return (NULL);
7636 }
7637
7638 static void
7639 dtrace_hash_remove(dtrace_hash_t *hash, dtrace_probe_t *probe)
7640 {
7641 int ndx = DTRACE_HASHSTR(hash, probe) & hash->dth_mask;
7642 dtrace_hashbucket_t *bucket = hash->dth_tab[ndx];
7643
7644 dtrace_probe_t **prevp = DTRACE_HASHPREV(hash, probe);
7645 dtrace_probe_t **nextp = DTRACE_HASHNEXT(hash, probe);
7646
7647 /*
7648 * Find the bucket that we're removing this probe from.
7649 */
7650 for (; bucket != NULL; bucket = bucket->dthb_next) {
7651 if (DTRACE_HASHEQ(hash, bucket->dthb_chain, probe))
7652 break;
7653 }
7654
7655 ASSERT(bucket != NULL);
7656
7657 if (*prevp == NULL) {
7658 if (*nextp == NULL) {
7659 /*
7660 * The removed probe was the only probe on this
7661 * bucket; we need to remove the bucket.
7662 */
7663 dtrace_hashbucket_t *b = hash->dth_tab[ndx];
7664
7665 ASSERT(bucket->dthb_chain == probe);
7666 ASSERT(b != NULL);
7667
7668 if (b == bucket) {
7669 hash->dth_tab[ndx] = bucket->dthb_next;
7670 } else {
7671 while (b->dthb_next != bucket)
7672 b = b->dthb_next;
7673 b->dthb_next = bucket->dthb_next;
7674 }
7675
7676 ASSERT(hash->dth_nbuckets > 0);
7677 hash->dth_nbuckets--;
7678 kmem_free(bucket, sizeof (dtrace_hashbucket_t));
7679 return;
7680 }
7681
7682 bucket->dthb_chain = *nextp;
7683 } else {
7684 *(DTRACE_HASHNEXT(hash, *prevp)) = *nextp;
7685 }
7686
7687 if (*nextp != NULL)
7688 *(DTRACE_HASHPREV(hash, *nextp)) = *prevp;
7689 }
7690
7691 /*
7692 * DTrace Utility Functions
7693 *
7694 * These are random utility functions that are _not_ called from probe context.
7695 */
7696 static int
7697 dtrace_badattr(const dtrace_attribute_t *a)
7698 {
7699 return (a->dtat_name > DTRACE_STABILITY_MAX ||
7700 a->dtat_data > DTRACE_STABILITY_MAX ||
7701 a->dtat_class > DTRACE_CLASS_MAX);
7702 }
7703
7704 /*
7705 * Return a duplicate copy of a string. If the specified string is NULL,
7706 * this function returns a zero-length string.
7707 */
7708 static char *
7709 dtrace_strdup(const char *str)
7710 {
7711 char *new = kmem_zalloc((str != NULL ? strlen(str) : 0) + 1, KM_SLEEP);
7712
7713 if (str != NULL)
7714 (void) strcpy(new, str);
7715
7716 return (new);
7717 }
7718
7719 #define DTRACE_ISALPHA(c) \
7720 (((c) >= 'a' && (c) <= 'z') || ((c) >= 'A' && (c) <= 'Z'))
7721
7722 static int
7723 dtrace_badname(const char *s)
7724 {
7725 char c;
7726
7727 if (s == NULL || (c = *s++) == '\0')
7728 return (0);
7729
7730 if (!DTRACE_ISALPHA(c) && c != '-' && c != '_' && c != '.')
7731 return (1);
7732
7733 while ((c = *s++) != '\0') {
7734 if (!DTRACE_ISALPHA(c) && (c < '0' || c > '9') &&
7735 c != '-' && c != '_' && c != '.' && c != '`')
7736 return (1);
7737 }
7738
7739 return (0);
7740 }
7741
7742 static void
7743 dtrace_cred2priv(cred_t *cr, uint32_t *privp, uid_t *uidp, zoneid_t *zoneidp)
7744 {
7745 uint32_t priv;
7746
7747 if (cr == NULL || PRIV_POLICY_ONLY(cr, PRIV_ALL, B_FALSE)) {
7748 /*
7749 * For DTRACE_PRIV_ALL, the uid and zoneid don't matter.
7750 */
7751 priv = DTRACE_PRIV_ALL;
7752 } else {
7753 *uidp = crgetuid(cr);
7754 *zoneidp = crgetzoneid(cr);
7755
7756 priv = 0;
7757 if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_KERNEL, B_FALSE))
7758 priv |= DTRACE_PRIV_KERNEL | DTRACE_PRIV_USER;
7759 else if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_USER, B_FALSE))
7760 priv |= DTRACE_PRIV_USER;
7761 if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_PROC, B_FALSE))
7762 priv |= DTRACE_PRIV_PROC;
7763 if (PRIV_POLICY_ONLY(cr, PRIV_PROC_OWNER, B_FALSE))
7764 priv |= DTRACE_PRIV_OWNER;
7765 if (PRIV_POLICY_ONLY(cr, PRIV_PROC_ZONE, B_FALSE))
7766 priv |= DTRACE_PRIV_ZONEOWNER;
7767 }
7768
7769 *privp = priv;
7770 }
7771
7772 #ifdef DTRACE_ERRDEBUG
7773 static void
7774 dtrace_errdebug(const char *str)
7775 {
7776 int hval = dtrace_hash_str((char *)str) % DTRACE_ERRHASHSZ;
7777 int occupied = 0;
7778
7779 mutex_enter(&dtrace_errlock);
7780 dtrace_errlast = str;
7781 dtrace_errthread = curthread;
7782
7783 while (occupied++ < DTRACE_ERRHASHSZ) {
7784 if (dtrace_errhash[hval].dter_msg == str) {
7785 dtrace_errhash[hval].dter_count++;
7786 goto out;
7787 }
7788
7789 if (dtrace_errhash[hval].dter_msg != NULL) {
7790 hval = (hval + 1) % DTRACE_ERRHASHSZ;
7791 continue;
7792 }
7793
7794 dtrace_errhash[hval].dter_msg = str;
7795 dtrace_errhash[hval].dter_count = 1;
7796 goto out;
7797 }
7798
7799 panic("dtrace: undersized error hash");
7800 out:
7801 mutex_exit(&dtrace_errlock);
7802 }
7803 #endif
7804
7805 /*
7806 * DTrace Matching Functions
7807 *
7808 * These functions are used to match groups of probes, given some elements of
7809 * a probe tuple, or some globbed expressions for elements of a probe tuple.
7810 */
7811 static int
7812 dtrace_match_priv(const dtrace_probe_t *prp, uint32_t priv, uid_t uid,
7813 zoneid_t zoneid)
7814 {
7815 if (priv != DTRACE_PRIV_ALL) {
7816 uint32_t ppriv = prp->dtpr_provider->dtpv_priv.dtpp_flags;
7817 uint32_t match = priv & ppriv;
7818
7819 /*
7820 * No PRIV_DTRACE_* privileges...
7821 */
7822 if ((priv & (DTRACE_PRIV_PROC | DTRACE_PRIV_USER |
7823 DTRACE_PRIV_KERNEL)) == 0)
7824 return (0);
7825
7826 /*
7827 * No matching bits, but there were bits to match...
7828 */
7829 if (match == 0 && ppriv != 0)
7830 return (0);
7831
7832 /*
7833 * Need to have permissions to the process, but don't...
7834 */
7835 if (((ppriv & ~match) & DTRACE_PRIV_OWNER) != 0 &&
7836 uid != prp->dtpr_provider->dtpv_priv.dtpp_uid) {
7837 return (0);
7838 }
7839
7840 /*
7841 * Need to be in the same zone unless we possess the
7842 * privilege to examine all zones.
7843 */
7844 if (((ppriv & ~match) & DTRACE_PRIV_ZONEOWNER) != 0 &&
7845 zoneid != prp->dtpr_provider->dtpv_priv.dtpp_zoneid) {
7846 return (0);
7847 }
7848 }
7849
7850 return (1);
7851 }
7852
7853 /*
7854 * dtrace_match_probe compares a dtrace_probe_t to a pre-compiled key, which
7855 * consists of input pattern strings and an ops-vector to evaluate them.
7856 * This function returns >0 for match, 0 for no match, and <0 for error.
7857 */
7858 static int
7859 dtrace_match_probe(const dtrace_probe_t *prp, const dtrace_probekey_t *pkp,
7860 uint32_t priv, uid_t uid, zoneid_t zoneid)
7861 {
7862 dtrace_provider_t *pvp = prp->dtpr_provider;
7863 int rv;
7864
7865 if (pvp->dtpv_defunct)
7866 return (0);
7867
7868 if ((rv = pkp->dtpk_pmatch(pvp->dtpv_name, pkp->dtpk_prov, 0)) <= 0)
7869 return (rv);
7870
7871 if ((rv = pkp->dtpk_mmatch(prp->dtpr_mod, pkp->dtpk_mod, 0)) <= 0)
7872 return (rv);
7873
7874 if ((rv = pkp->dtpk_fmatch(prp->dtpr_func, pkp->dtpk_func, 0)) <= 0)
7875 return (rv);
7876
7877 if ((rv = pkp->dtpk_nmatch(prp->dtpr_name, pkp->dtpk_name, 0)) <= 0)
7878 return (rv);
7879
7880 if (dtrace_match_priv(prp, priv, uid, zoneid) == 0)
7881 return (0);
7882
7883 return (rv);
7884 }
7885
7886 /*
7887 * dtrace_match_glob() is a safe kernel implementation of the gmatch(3GEN)
7888 * interface for matching a glob pattern 'p' to an input string 's'. Unlike
7889 * libc's version, the kernel version only applies to 8-bit ASCII strings.
7890 * In addition, all of the recursion cases except for '*' matching have been
7891 * unwound. For '*', we still implement recursive evaluation, but a depth
7892 * counter is maintained and matching is aborted if we recurse too deep.
7893 * The function returns 0 if no match, >0 if match, and <0 if recursion error.
7894 */
7895 static int
7896 dtrace_match_glob(const char *s, const char *p, int depth)
7897 {
7898 const char *olds;
7899 char s1, c;
7900 int gs;
7901
7902 if (depth > DTRACE_PROBEKEY_MAXDEPTH)
7903 return (-1);
7904
7905 if (s == NULL)
7906 s = ""; /* treat NULL as empty string */
7907
7908 top:
7909 olds = s;
7910 s1 = *s++;
7911
7912 if (p == NULL)
7913 return (0);
7914
7915 if ((c = *p++) == '\0')
7916 return (s1 == '\0');
7917
7918 switch (c) {
7919 case '[': {
7920 int ok = 0, notflag = 0;
7921 char lc = '\0';
7922
7923 if (s1 == '\0')
7924 return (0);
7925
7926 if (*p == '!') {
7927 notflag = 1;
7928 p++;
7929 }
7930
7931 if ((c = *p++) == '\0')
7932 return (0);
7933
7934 do {
7935 if (c == '-' && lc != '\0' && *p != ']') {
7936 if ((c = *p++) == '\0')
7937 return (0);
7938 if (c == '\\' && (c = *p++) == '\0')
7939 return (0);
7940
7941 if (notflag) {
7942 if (s1 < lc || s1 > c)
7943 ok++;
7944 else
7945 return (0);
7946 } else if (lc <= s1 && s1 <= c)
7947 ok++;
7948
7949 } else if (c == '\\' && (c = *p++) == '\0')
7950 return (0);
7951
7952 lc = c; /* save left-hand 'c' for next iteration */
7953
7954 if (notflag) {
7955 if (s1 != c)
7956 ok++;
7957 else
7958 return (0);
7959 } else if (s1 == c)
7960 ok++;
7961
7962 if ((c = *p++) == '\0')
7963 return (0);
7964
7965 } while (c != ']');
7966
7967 if (ok)
7968 goto top;
7969
7970 return (0);
7971 }
7972
7973 case '\\':
7974 if ((c = *p++) == '\0')
7975 return (0);
7976 /*FALLTHRU*/
7977
7978 default:
7979 if (c != s1)
7980 return (0);
7981 /*FALLTHRU*/
7982
7983 case '?':
7984 if (s1 != '\0')
7985 goto top;
7986 return (0);
7987
7988 case '*':
7989 while (*p == '*')
7990 p++; /* consecutive *'s are identical to a single one */
7991
7992 if (*p == '\0')
7993 return (1);
7994
7995 for (s = olds; *s != '\0'; s++) {
7996 if ((gs = dtrace_match_glob(s, p, depth + 1)) != 0)
7997 return (gs);
7998 }
7999
8000 return (0);
8001 }
8002 }
8003
8004 /*ARGSUSED*/
8005 static int
8006 dtrace_match_string(const char *s, const char *p, int depth)
8007 {
8008 return (s != NULL && strcmp(s, p) == 0);
8009 }
8010
8011 /*ARGSUSED*/
8012 static int
8013 dtrace_match_nul(const char *s, const char *p, int depth)
8014 {
8015 return (1); /* always match the empty pattern */
8016 }
8017
8018 /*ARGSUSED*/
8019 static int
8020 dtrace_match_nonzero(const char *s, const char *p, int depth)
8021 {
8022 return (s != NULL && s[0] != '\0');
8023 }
8024
8025 static int
8026 dtrace_match(const dtrace_probekey_t *pkp, uint32_t priv, uid_t uid,
8027 zoneid_t zoneid, int (*matched)(dtrace_probe_t *, void *), void *arg)
8028 {
8029 dtrace_probe_t template, *probe;
8030 dtrace_hash_t *hash = NULL;
8031 int len, rc, best = INT_MAX, nmatched = 0;
8032 dtrace_id_t i;
8033
8034 ASSERT(MUTEX_HELD(&dtrace_lock));
8035
8036 /*
8037 * If the probe ID is specified in the key, just lookup by ID and
8038 * invoke the match callback once if a matching probe is found.
8039 */
8040 if (pkp->dtpk_id != DTRACE_IDNONE) {
8041 if ((probe = dtrace_probe_lookup_id(pkp->dtpk_id)) != NULL &&
8042 dtrace_match_probe(probe, pkp, priv, uid, zoneid) > 0) {
8043 if ((*matched)(probe, arg) == DTRACE_MATCH_FAIL)
8044 return (DTRACE_MATCH_FAIL);
8045 nmatched++;
8046 }
8047 return (nmatched);
8048 }
8049
8050 template.dtpr_mod = (char *)pkp->dtpk_mod;
8051 template.dtpr_func = (char *)pkp->dtpk_func;
8052 template.dtpr_name = (char *)pkp->dtpk_name;
8053
8054 /*
8055 * We want to find the most distinct of the module name, function
8056 * name, and name. So for each one that is not a glob pattern or
8057 * empty string, we perform a lookup in the corresponding hash and
8058 * use the hash table with the fewest collisions to do our search.
8059 */
8060 if (pkp->dtpk_mmatch == &dtrace_match_string &&
8061 (len = dtrace_hash_collisions(dtrace_bymod, &template)) < best) {
8062 best = len;
8063 hash = dtrace_bymod;
8064 }
8065
8066 if (pkp->dtpk_fmatch == &dtrace_match_string &&
8067 (len = dtrace_hash_collisions(dtrace_byfunc, &template)) < best) {
8068 best = len;
8069 hash = dtrace_byfunc;
8070 }
8071
8072 if (pkp->dtpk_nmatch == &dtrace_match_string &&
8073 (len = dtrace_hash_collisions(dtrace_byname, &template)) < best) {
8074 best = len;
8075 hash = dtrace_byname;
8076 }
8077
8078 /*
8079 * If we did not select a hash table, iterate over every probe and
8080 * invoke our callback for each one that matches our input probe key.
8081 */
8082 if (hash == NULL) {
8083 for (i = 0; i < dtrace_nprobes; i++) {
8084 if ((probe = dtrace_probes[i]) == NULL ||
8085 dtrace_match_probe(probe, pkp, priv, uid,
8086 zoneid) <= 0)
8087 continue;
8088
8089 nmatched++;
8090
8091 if ((rc = (*matched)(probe, arg)) !=
8092 DTRACE_MATCH_NEXT) {
8093 if (rc == DTRACE_MATCH_FAIL)
8094 return (DTRACE_MATCH_FAIL);
8095 break;
8096 }
8097 }
8098
8099 return (nmatched);
8100 }
8101
8102 /*
8103 * If we selected a hash table, iterate over each probe of the same key
8104 * name and invoke the callback for every probe that matches the other
8105 * attributes of our input probe key.
8106 */
8107 for (probe = dtrace_hash_lookup(hash, &template); probe != NULL;
8108 probe = *(DTRACE_HASHNEXT(hash, probe))) {
8109
8110 if (dtrace_match_probe(probe, pkp, priv, uid, zoneid) <= 0)
8111 continue;
8112
8113 nmatched++;
8114
8115 if ((rc = (*matched)(probe, arg)) != DTRACE_MATCH_NEXT) {
8116 if (rc == DTRACE_MATCH_FAIL)
8117 return (DTRACE_MATCH_FAIL);
8118 break;
8119 }
8120 }
8121
8122 return (nmatched);
8123 }
8124
8125 /*
8126 * Return the function pointer dtrace_probecmp() should use to compare the
8127 * specified pattern with a string. For NULL or empty patterns, we select
8128 * dtrace_match_nul(). For glob pattern strings, we use dtrace_match_glob().
8129 * For non-empty non-glob strings, we use dtrace_match_string().
8130 */
8131 static dtrace_probekey_f *
8132 dtrace_probekey_func(const char *p)
8133 {
8134 char c;
8135
8136 if (p == NULL || *p == '\0')
8137 return (&dtrace_match_nul);
8138
8139 while ((c = *p++) != '\0') {
8140 if (c == '[' || c == '?' || c == '*' || c == '\\')
8141 return (&dtrace_match_glob);
8142 }
8143
8144 return (&dtrace_match_string);
8145 }
8146
8147 /*
8148 * Build a probe comparison key for use with dtrace_match_probe() from the
8149 * given probe description. By convention, a null key only matches anchored
8150 * probes: if each field is the empty string, reset dtpk_fmatch to
8151 * dtrace_match_nonzero().
8152 */
8153 static void
8154 dtrace_probekey(const dtrace_probedesc_t *pdp, dtrace_probekey_t *pkp)
8155 {
8156 pkp->dtpk_prov = pdp->dtpd_provider;
8157 pkp->dtpk_pmatch = dtrace_probekey_func(pdp->dtpd_provider);
8158
8159 pkp->dtpk_mod = pdp->dtpd_mod;
8160 pkp->dtpk_mmatch = dtrace_probekey_func(pdp->dtpd_mod);
8161
8162 pkp->dtpk_func = pdp->dtpd_func;
8163 pkp->dtpk_fmatch = dtrace_probekey_func(pdp->dtpd_func);
8164
8165 pkp->dtpk_name = pdp->dtpd_name;
8166 pkp->dtpk_nmatch = dtrace_probekey_func(pdp->dtpd_name);
8167
8168 pkp->dtpk_id = pdp->dtpd_id;
8169
8170 if (pkp->dtpk_id == DTRACE_IDNONE &&
8171 pkp->dtpk_pmatch == &dtrace_match_nul &&
8172 pkp->dtpk_mmatch == &dtrace_match_nul &&
8173 pkp->dtpk_fmatch == &dtrace_match_nul &&
8174 pkp->dtpk_nmatch == &dtrace_match_nul)
8175 pkp->dtpk_fmatch = &dtrace_match_nonzero;
8176 }
8177
8178 /*
8179 * DTrace Provider-to-Framework API Functions
8180 *
8181 * These functions implement much of the Provider-to-Framework API, as
8182 * described in <sys/dtrace.h>. The parts of the API not in this section are
8183 * the functions in the API for probe management (found below), and
8184 * dtrace_probe() itself (found above).
8185 */
8186
8187 /*
8188 * Register the calling provider with the DTrace framework. This should
8189 * generally be called by DTrace providers in their attach(9E) entry point.
8190 */
8191 int
8192 dtrace_register(const char *name, const dtrace_pattr_t *pap, uint32_t priv,
8193 cred_t *cr, const dtrace_pops_t *pops, void *arg, dtrace_provider_id_t *idp)
8194 {
8195 dtrace_provider_t *provider;
8196
8197 if (name == NULL || pap == NULL || pops == NULL || idp == NULL) {
8198 cmn_err(CE_WARN, "failed to register provider '%s': invalid "
8199 "arguments", name ? name : "<NULL>");
8200 return (EINVAL);
8201 }
8202
8203 if (name[0] == '\0' || dtrace_badname(name)) {
8204 cmn_err(CE_WARN, "failed to register provider '%s': invalid "
8205 "provider name", name);
8206 return (EINVAL);
8207 }
8208
8209 if ((pops->dtps_provide == NULL && pops->dtps_provide_module == NULL) ||
8210 pops->dtps_enable == NULL || pops->dtps_disable == NULL ||
8211 pops->dtps_destroy == NULL ||
8212 ((pops->dtps_resume == NULL) != (pops->dtps_suspend == NULL))) {
8213 cmn_err(CE_WARN, "failed to register provider '%s': invalid "
8214 "provider ops", name);
8215 return (EINVAL);
8216 }
8217
8218 if (dtrace_badattr(&pap->dtpa_provider) ||
8219 dtrace_badattr(&pap->dtpa_mod) ||
8220 dtrace_badattr(&pap->dtpa_func) ||
8221 dtrace_badattr(&pap->dtpa_name) ||
8222 dtrace_badattr(&pap->dtpa_args)) {
8223 cmn_err(CE_WARN, "failed to register provider '%s': invalid "
8224 "provider attributes", name);
8225 return (EINVAL);
8226 }
8227
8228 if (priv & ~DTRACE_PRIV_ALL) {
8229 cmn_err(CE_WARN, "failed to register provider '%s': invalid "
8230 "privilege attributes", name);
8231 return (EINVAL);
8232 }
8233
8234 if ((priv & DTRACE_PRIV_KERNEL) &&
8235 (priv & (DTRACE_PRIV_USER | DTRACE_PRIV_OWNER)) &&
8236 pops->dtps_mode == NULL) {
8237 cmn_err(CE_WARN, "failed to register provider '%s': need "
8238 "dtps_mode() op for given privilege attributes", name);
8239 return (EINVAL);
8240 }
8241
8242 provider = kmem_zalloc(sizeof (dtrace_provider_t), KM_SLEEP);
8243 provider->dtpv_name = kmem_alloc(strlen(name) + 1, KM_SLEEP);
8244 (void) strcpy(provider->dtpv_name, name);
8245
8246 provider->dtpv_attr = *pap;
8247 provider->dtpv_priv.dtpp_flags = priv;
8248 if (cr != NULL) {
8249 provider->dtpv_priv.dtpp_uid = crgetuid(cr);
8250 provider->dtpv_priv.dtpp_zoneid = crgetzoneid(cr);
8251 }
8252 provider->dtpv_pops = *pops;
8253
8254 if (pops->dtps_provide == NULL) {
8255 ASSERT(pops->dtps_provide_module != NULL);
8256 provider->dtpv_pops.dtps_provide =
8257 (void (*)(void *, const dtrace_probedesc_t *))dtrace_nullop;
8258 }
8259
8260 if (pops->dtps_provide_module == NULL) {
8261 ASSERT(pops->dtps_provide != NULL);
8262 provider->dtpv_pops.dtps_provide_module =
8263 (void (*)(void *, struct modctl *))dtrace_nullop;
8264 }
8265
8266 if (pops->dtps_suspend == NULL) {
8267 ASSERT(pops->dtps_resume == NULL);
8268 provider->dtpv_pops.dtps_suspend =
8269 (void (*)(void *, dtrace_id_t, void *))dtrace_nullop;
8270 provider->dtpv_pops.dtps_resume =
8271 (void (*)(void *, dtrace_id_t, void *))dtrace_nullop;
8272 }
8273
8274 provider->dtpv_arg = arg;
8275 *idp = (dtrace_provider_id_t)provider;
8276
8277 if (pops == &dtrace_provider_ops) {
8278 ASSERT(MUTEX_HELD(&dtrace_provider_lock));
8279 ASSERT(MUTEX_HELD(&dtrace_lock));
8280 ASSERT(dtrace_anon.dta_enabling == NULL);
8281
8282 /*
8283 * We make sure that the DTrace provider is at the head of
8284 * the provider chain.
8285 */
8286 provider->dtpv_next = dtrace_provider;
8287 dtrace_provider = provider;
8288 return (0);
8289 }
8290
8291 mutex_enter(&dtrace_provider_lock);
8292 mutex_enter(&dtrace_lock);
8293
8294 /*
8295 * If there is at least one provider registered, we'll add this
8296 * provider after the first provider.
8297 */
8298 if (dtrace_provider != NULL) {
8299 provider->dtpv_next = dtrace_provider->dtpv_next;
8300 dtrace_provider->dtpv_next = provider;
8301 } else {
8302 dtrace_provider = provider;
8303 }
8304
8305 if (dtrace_retained != NULL) {
8306 dtrace_enabling_provide(provider);
8307
8308 /*
8309 * Now we need to call dtrace_enabling_matchall() -- which
8310 * will acquire cpu_lock and dtrace_lock. We therefore need
8311 * to drop all of our locks before calling into it...
8312 */
8313 mutex_exit(&dtrace_lock);
8314 mutex_exit(&dtrace_provider_lock);
8315 dtrace_enabling_matchall();
8316
8317 return (0);
8318 }
8319
8320 mutex_exit(&dtrace_lock);
8321 mutex_exit(&dtrace_provider_lock);
8322
8323 return (0);
8324 }
8325
8326 /*
8327 * Unregister the specified provider from the DTrace framework. This should
8328 * generally be called by DTrace providers in their detach(9E) entry point.
8329 */
8330 int
8331 dtrace_unregister(dtrace_provider_id_t id)
8332 {
8333 dtrace_provider_t *old = (dtrace_provider_t *)id;
8334 dtrace_provider_t *prev = NULL;
8335 int i, self = 0, noreap = 0;
8336 dtrace_probe_t *probe, *first = NULL;
8337
8338 if (old->dtpv_pops.dtps_enable ==
8339 (int (*)(void *, dtrace_id_t, void *))dtrace_enable_nullop) {
8340 /*
8341 * If DTrace itself is the provider, we're called with locks
8342 * already held.
8343 */
8344 ASSERT(old == dtrace_provider);
8345 ASSERT(dtrace_devi != NULL);
8346 ASSERT(MUTEX_HELD(&dtrace_provider_lock));
8347 ASSERT(MUTEX_HELD(&dtrace_lock));
8348 self = 1;
8349
8350 if (dtrace_provider->dtpv_next != NULL) {
8351 /*
8352 * There's another provider here; return failure.
8353 */
8354 return (EBUSY);
8355 }
8356 } else {
8357 mutex_enter(&dtrace_provider_lock);
8358 mutex_enter(&mod_lock);
8359 mutex_enter(&dtrace_lock);
8360 }
8361
8362 /*
8363 * If anyone has /dev/dtrace open, or if there are anonymous enabled
8364 * probes, we refuse to let providers slither away, unless this
8365 * provider has already been explicitly invalidated.
8366 */
8367 if (!old->dtpv_defunct &&
8368 (dtrace_opens || (dtrace_anon.dta_state != NULL &&
8369 dtrace_anon.dta_state->dts_necbs > 0))) {
8370 if (!self) {
8371 mutex_exit(&dtrace_lock);
8372 mutex_exit(&mod_lock);
8373 mutex_exit(&dtrace_provider_lock);
8374 }
8375 return (EBUSY);
8376 }
8377
8378 /*
8379 * Attempt to destroy the probes associated with this provider.
8380 */
8381 for (i = 0; i < dtrace_nprobes; i++) {
8382 if ((probe = dtrace_probes[i]) == NULL)
8383 continue;
8384
8385 if (probe->dtpr_provider != old)
8386 continue;
8387
8388 if (probe->dtpr_ecb == NULL)
8389 continue;
8390
8391 /*
8392 * If we are trying to unregister a defunct provider, and the
8393 * provider was made defunct within the interval dictated by
8394 * dtrace_unregister_defunct_reap, we'll (asynchronously)
8395 * attempt to reap our enablings. To denote that the provider
8396 * should reattempt to unregister itself at some point in the
8397 * future, we will return a differentiable error code (EAGAIN
8398 * instead of EBUSY) in this case.
8399 */
8400 if (dtrace_gethrtime() - old->dtpv_defunct >
8401 dtrace_unregister_defunct_reap)
8402 noreap = 1;
8403
8404 if (!self) {
8405 mutex_exit(&dtrace_lock);
8406 mutex_exit(&mod_lock);
8407 mutex_exit(&dtrace_provider_lock);
8408 }
8409
8410 if (noreap)
8411 return (EBUSY);
8412
8413 (void) taskq_dispatch(dtrace_taskq,
8414 (task_func_t *)dtrace_enabling_reap, NULL, TQ_SLEEP);
8415
8416 return (EAGAIN);
8417 }
8418
8419 /*
8420 * All of the probes for this provider are disabled; we can safely
8421 * remove all of them from their hash chains and from the probe array.
8422 */
8423 for (i = 0; i < dtrace_nprobes; i++) {
8424 if ((probe = dtrace_probes[i]) == NULL)
8425 continue;
8426
8427 if (probe->dtpr_provider != old)
8428 continue;
8429
8430 dtrace_probes[i] = NULL;
8431
8432 dtrace_hash_remove(dtrace_bymod, probe);
8433 dtrace_hash_remove(dtrace_byfunc, probe);
8434 dtrace_hash_remove(dtrace_byname, probe);
8435
8436 if (first == NULL) {
8437 first = probe;
8438 probe->dtpr_nextmod = NULL;
8439 } else {
8440 probe->dtpr_nextmod = first;
8441 first = probe;
8442 }
8443 }
8444
8445 /*
8446 * The provider's probes have been removed from the hash chains and
8447 * from the probe array. Now issue a dtrace_sync() to be sure that
8448 * everyone has cleared out from any probe array processing.
8449 */
8450 dtrace_sync();
8451
8452 for (probe = first; probe != NULL; probe = first) {
8453 first = probe->dtpr_nextmod;
8454
8455 old->dtpv_pops.dtps_destroy(old->dtpv_arg, probe->dtpr_id,
8456 probe->dtpr_arg);
8457 kmem_free(probe->dtpr_mod, strlen(probe->dtpr_mod) + 1);
8458 kmem_free(probe->dtpr_func, strlen(probe->dtpr_func) + 1);
8459 kmem_free(probe->dtpr_name, strlen(probe->dtpr_name) + 1);
8460 vmem_free(dtrace_arena, (void *)(uintptr_t)(probe->dtpr_id), 1);
8461 kmem_free(probe, sizeof (dtrace_probe_t));
8462 }
8463
8464 if ((prev = dtrace_provider) == old) {
8465 ASSERT(self || dtrace_devi == NULL);
8466 ASSERT(old->dtpv_next == NULL || dtrace_devi == NULL);
8467 dtrace_provider = old->dtpv_next;
8468 } else {
8469 while (prev != NULL && prev->dtpv_next != old)
8470 prev = prev->dtpv_next;
8471
8472 if (prev == NULL) {
8473 panic("attempt to unregister non-existent "
8474 "dtrace provider %p\n", (void *)id);
8475 }
8476
8477 prev->dtpv_next = old->dtpv_next;
8478 }
8479
8480 if (!self) {
8481 mutex_exit(&dtrace_lock);
8482 mutex_exit(&mod_lock);
8483 mutex_exit(&dtrace_provider_lock);
8484 }
8485
8486 kmem_free(old->dtpv_name, strlen(old->dtpv_name) + 1);
8487 kmem_free(old, sizeof (dtrace_provider_t));
8488
8489 return (0);
8490 }
8491
8492 /*
8493 * Invalidate the specified provider. All subsequent probe lookups for the
8494 * specified provider will fail, but its probes will not be removed.
8495 */
8496 void
8497 dtrace_invalidate(dtrace_provider_id_t id)
8498 {
8499 dtrace_provider_t *pvp = (dtrace_provider_t *)id;
8500
8501 ASSERT(pvp->dtpv_pops.dtps_enable !=
8502 (int (*)(void *, dtrace_id_t, void *))dtrace_enable_nullop);
8503
8504 mutex_enter(&dtrace_provider_lock);
8505 mutex_enter(&dtrace_lock);
8506
8507 pvp->dtpv_defunct = dtrace_gethrtime();
8508
8509 mutex_exit(&dtrace_lock);
8510 mutex_exit(&dtrace_provider_lock);
8511 }
8512
8513 /*
8514 * Indicate whether or not DTrace has attached.
8515 */
8516 int
8517 dtrace_attached(void)
8518 {
8519 /*
8520 * dtrace_provider will be non-NULL iff the DTrace driver has
8521 * attached. (It's non-NULL because DTrace is always itself a
8522 * provider.)
8523 */
8524 return (dtrace_provider != NULL);
8525 }
8526
8527 /*
8528 * Remove all the unenabled probes for the given provider. This function is
8529 * not unlike dtrace_unregister(), except that it doesn't remove the provider
8530 * -- just as many of its associated probes as it can.
8531 */
8532 int
8533 dtrace_condense(dtrace_provider_id_t id)
8534 {
8535 dtrace_provider_t *prov = (dtrace_provider_t *)id;
8536 int i;
8537 dtrace_probe_t *probe;
8538
8539 /*
8540 * Make sure this isn't the dtrace provider itself.
8541 */
8542 ASSERT(prov->dtpv_pops.dtps_enable !=
8543 (int (*)(void *, dtrace_id_t, void *))dtrace_enable_nullop);
8544
8545 mutex_enter(&dtrace_provider_lock);
8546 mutex_enter(&dtrace_lock);
8547
8548 /*
8549 * Attempt to destroy the probes associated with this provider.
8550 */
8551 for (i = 0; i < dtrace_nprobes; i++) {
8552 if ((probe = dtrace_probes[i]) == NULL)
8553 continue;
8554
8555 if (probe->dtpr_provider != prov)
8556 continue;
8557
8558 if (probe->dtpr_ecb != NULL)
8559 continue;
8560
8561 dtrace_probes[i] = NULL;
8562
8563 dtrace_hash_remove(dtrace_bymod, probe);
8564 dtrace_hash_remove(dtrace_byfunc, probe);
8565 dtrace_hash_remove(dtrace_byname, probe);
8566
8567 prov->dtpv_pops.dtps_destroy(prov->dtpv_arg, i + 1,
8568 probe->dtpr_arg);
8569 kmem_free(probe->dtpr_mod, strlen(probe->dtpr_mod) + 1);
8570 kmem_free(probe->dtpr_func, strlen(probe->dtpr_func) + 1);
8571 kmem_free(probe->dtpr_name, strlen(probe->dtpr_name) + 1);
8572 kmem_free(probe, sizeof (dtrace_probe_t));
8573 vmem_free(dtrace_arena, (void *)((uintptr_t)i + 1), 1);
8574 }
8575
8576 mutex_exit(&dtrace_lock);
8577 mutex_exit(&dtrace_provider_lock);
8578
8579 return (0);
8580 }
8581
8582 /*
8583 * DTrace Probe Management Functions
8584 *
8585 * The functions in this section perform the DTrace probe management,
8586 * including functions to create probes, look-up probes, and call into the
8587 * providers to request that probes be provided. Some of these functions are
8588 * in the Provider-to-Framework API; these functions can be identified by the
8589 * fact that they are not declared "static".
8590 */
8591
8592 /*
8593 * Create a probe with the specified module name, function name, and name.
8594 */
8595 dtrace_id_t
8596 dtrace_probe_create(dtrace_provider_id_t prov, const char *mod,
8597 const char *func, const char *name, int aframes, void *arg)
8598 {
8599 dtrace_probe_t *probe, **probes;
8600 dtrace_provider_t *provider = (dtrace_provider_t *)prov;
8601 dtrace_id_t id;
8602
8603 if (provider == dtrace_provider) {
8604 ASSERT(MUTEX_HELD(&dtrace_lock));
8605 } else {
8606 mutex_enter(&dtrace_lock);
8607 }
8608
8609 id = (dtrace_id_t)(uintptr_t)vmem_alloc(dtrace_arena, 1,
8610 VM_BESTFIT | VM_SLEEP);
8611 probe = kmem_zalloc(sizeof (dtrace_probe_t), KM_SLEEP);
8612
8613 probe->dtpr_id = id;
8614 probe->dtpr_gen = dtrace_probegen++;
8615 probe->dtpr_mod = dtrace_strdup(mod);
8616 probe->dtpr_func = dtrace_strdup(func);
8617 probe->dtpr_name = dtrace_strdup(name);
8618 probe->dtpr_arg = arg;
8619 probe->dtpr_aframes = aframes;
8620 probe->dtpr_provider = provider;
8621
8622 dtrace_hash_add(dtrace_bymod, probe);
8623 dtrace_hash_add(dtrace_byfunc, probe);
8624 dtrace_hash_add(dtrace_byname, probe);
8625
8626 if (id - 1 >= dtrace_nprobes) {
8627 size_t osize = dtrace_nprobes * sizeof (dtrace_probe_t *);
8628 size_t nsize = osize << 1;
8629
8630 if (nsize == 0) {
8631 ASSERT(osize == 0);
8632 ASSERT(dtrace_probes == NULL);
8633 nsize = sizeof (dtrace_probe_t *);
8634 }
8635
8636 probes = kmem_zalloc(nsize, KM_SLEEP);
8637
8638 if (dtrace_probes == NULL) {
8639 ASSERT(osize == 0);
8640 dtrace_probes = probes;
8641 dtrace_nprobes = 1;
8642 } else {
8643 dtrace_probe_t **oprobes = dtrace_probes;
8644
8645 bcopy(oprobes, probes, osize);
8646 dtrace_membar_producer();
8647 dtrace_probes = probes;
8648
8649 dtrace_sync();
8650
8651 /*
8652 * All CPUs are now seeing the new probes array; we can
8653 * safely free the old array.
8654 */
8655 kmem_free(oprobes, osize);
8656 dtrace_nprobes <<= 1;
8657 }
8658
8659 ASSERT(id - 1 < dtrace_nprobes);
8660 }
8661
8662 ASSERT(dtrace_probes[id - 1] == NULL);
8663 dtrace_probes[id - 1] = probe;
8664
8665 if (provider != dtrace_provider)
8666 mutex_exit(&dtrace_lock);
8667
8668 return (id);
8669 }
8670
8671 static dtrace_probe_t *
8672 dtrace_probe_lookup_id(dtrace_id_t id)
8673 {
8674 ASSERT(MUTEX_HELD(&dtrace_lock));
8675
8676 if (id == 0 || id > dtrace_nprobes)
8677 return (NULL);
8678
8679 return (dtrace_probes[id - 1]);
8680 }
8681
8682 static int
8683 dtrace_probe_lookup_match(dtrace_probe_t *probe, void *arg)
8684 {
8685 *((dtrace_id_t *)arg) = probe->dtpr_id;
8686
8687 return (DTRACE_MATCH_DONE);
8688 }
8689
8690 /*
8691 * Look up a probe based on provider and one or more of module name, function
8692 * name and probe name.
8693 */
8694 dtrace_id_t
8695 dtrace_probe_lookup(dtrace_provider_id_t prid, const char *mod,
8696 const char *func, const char *name)
8697 {
8698 dtrace_probekey_t pkey;
8699 dtrace_id_t id;
8700 int match;
8701
8702 pkey.dtpk_prov = ((dtrace_provider_t *)prid)->dtpv_name;
8703 pkey.dtpk_pmatch = &dtrace_match_string;
8704 pkey.dtpk_mod = mod;
8705 pkey.dtpk_mmatch = mod ? &dtrace_match_string : &dtrace_match_nul;
8706 pkey.dtpk_func = func;
8707 pkey.dtpk_fmatch = func ? &dtrace_match_string : &dtrace_match_nul;
8708 pkey.dtpk_name = name;
8709 pkey.dtpk_nmatch = name ? &dtrace_match_string : &dtrace_match_nul;
8710 pkey.dtpk_id = DTRACE_IDNONE;
8711
8712 mutex_enter(&dtrace_lock);
8713 match = dtrace_match(&pkey, DTRACE_PRIV_ALL, 0, 0,
8714 dtrace_probe_lookup_match, &id);
8715 mutex_exit(&dtrace_lock);
8716
8717 ASSERT(match == 1 || match == 0);
8718 return (match ? id : 0);
8719 }
8720
8721 /*
8722 * Returns the probe argument associated with the specified probe.
8723 */
8724 void *
8725 dtrace_probe_arg(dtrace_provider_id_t id, dtrace_id_t pid)
8726 {
8727 dtrace_probe_t *probe;
8728 void *rval = NULL;
8729
8730 mutex_enter(&dtrace_lock);
8731
8732 if ((probe = dtrace_probe_lookup_id(pid)) != NULL &&
8733 probe->dtpr_provider == (dtrace_provider_t *)id)
8734 rval = probe->dtpr_arg;
8735
8736 mutex_exit(&dtrace_lock);
8737
8738 return (rval);
8739 }
8740
8741 /*
8742 * Copy a probe into a probe description.
8743 */
8744 static void
8745 dtrace_probe_description(const dtrace_probe_t *prp, dtrace_probedesc_t *pdp)
8746 {
8747 bzero(pdp, sizeof (dtrace_probedesc_t));
8748 pdp->dtpd_id = prp->dtpr_id;
8749
8750 (void) strncpy(pdp->dtpd_provider,
8751 prp->dtpr_provider->dtpv_name, DTRACE_PROVNAMELEN - 1);
8752
8753 (void) strncpy(pdp->dtpd_mod, prp->dtpr_mod, DTRACE_MODNAMELEN - 1);
8754 (void) strncpy(pdp->dtpd_func, prp->dtpr_func, DTRACE_FUNCNAMELEN - 1);
8755 (void) strncpy(pdp->dtpd_name, prp->dtpr_name, DTRACE_NAMELEN - 1);
8756 }
8757
8758 /*
8759 * Called to indicate that a probe -- or probes -- should be provided by a
8760 * specfied provider. If the specified description is NULL, the provider will
8761 * be told to provide all of its probes. (This is done whenever a new
8762 * consumer comes along, or whenever a retained enabling is to be matched.) If
8763 * the specified description is non-NULL, the provider is given the
8764 * opportunity to dynamically provide the specified probe, allowing providers
8765 * to support the creation of probes on-the-fly. (So-called _autocreated_
8766 * probes.) If the provider is NULL, the operations will be applied to all
8767 * providers; if the provider is non-NULL the operations will only be applied
8768 * to the specified provider. The dtrace_provider_lock must be held, and the
8769 * dtrace_lock must _not_ be held -- the provider's dtps_provide() operation
8770 * will need to grab the dtrace_lock when it reenters the framework through
8771 * dtrace_probe_lookup(), dtrace_probe_create(), etc.
8772 */
8773 static void
8774 dtrace_probe_provide(dtrace_probedesc_t *desc, dtrace_provider_t *prv)
8775 {
8776 struct modctl *ctl;
8777 int all = 0;
8778
8779 ASSERT(MUTEX_HELD(&dtrace_provider_lock));
8780
8781 if (prv == NULL) {
8782 all = 1;
8783 prv = dtrace_provider;
8784 }
8785
8786 do {
8787 /*
8788 * First, call the blanket provide operation.
8789 */
8790 prv->dtpv_pops.dtps_provide(prv->dtpv_arg, desc);
8791
8792 /*
8793 * Now call the per-module provide operation. We will grab
8794 * mod_lock to prevent the list from being modified. Note
8795 * that this also prevents the mod_busy bits from changing.
8796 * (mod_busy can only be changed with mod_lock held.)
8797 */
8798 mutex_enter(&mod_lock);
8799
8800 ctl = &modules;
8801 do {
8802 if (ctl->mod_busy || ctl->mod_mp == NULL)
8803 continue;
8804
8805 prv->dtpv_pops.dtps_provide_module(prv->dtpv_arg, ctl);
8806
8807 } while ((ctl = ctl->mod_next) != &modules);
8808
8809 mutex_exit(&mod_lock);
8810 } while (all && (prv = prv->dtpv_next) != NULL);
8811 }
8812
8813 /*
8814 * Iterate over each probe, and call the Framework-to-Provider API function
8815 * denoted by offs.
8816 */
8817 static void
8818 dtrace_probe_foreach(uintptr_t offs)
8819 {
8820 dtrace_provider_t *prov;
8821 void (*func)(void *, dtrace_id_t, void *);
8822 dtrace_probe_t *probe;
8823 dtrace_icookie_t cookie;
8824 int i;
8825
8826 /*
8827 * We disable interrupts to walk through the probe array. This is
8828 * safe -- the dtrace_sync() in dtrace_unregister() assures that we
8829 * won't see stale data.
8830 */
8831 cookie = dtrace_interrupt_disable();
8832
8833 for (i = 0; i < dtrace_nprobes; i++) {
8834 if ((probe = dtrace_probes[i]) == NULL)
8835 continue;
8836
8837 if (probe->dtpr_ecb == NULL) {
8838 /*
8839 * This probe isn't enabled -- don't call the function.
8840 */
8841 continue;
8842 }
8843
8844 prov = probe->dtpr_provider;
8845 func = *((void(**)(void *, dtrace_id_t, void *))
8846 ((uintptr_t)&prov->dtpv_pops + offs));
8847
8848 func(prov->dtpv_arg, i + 1, probe->dtpr_arg);
8849 }
8850
8851 dtrace_interrupt_enable(cookie);
8852 }
8853
8854 static int
8855 dtrace_probe_enable(const dtrace_probedesc_t *desc, dtrace_enabling_t *enab)
8856 {
8857 dtrace_probekey_t pkey;
8858 uint32_t priv;
8859 uid_t uid;
8860 zoneid_t zoneid;
8861
8862 ASSERT(MUTEX_HELD(&dtrace_lock));
8863 dtrace_ecb_create_cache = NULL;
8864
8865 if (desc == NULL) {
8866 /*
8867 * If we're passed a NULL description, we're being asked to
8868 * create an ECB with a NULL probe.
8869 */
8870 (void) dtrace_ecb_create_enable(NULL, enab);
8871 return (0);
8872 }
8873
8874 dtrace_probekey(desc, &pkey);
8875 dtrace_cred2priv(enab->dten_vstate->dtvs_state->dts_cred.dcr_cred,
8876 &priv, &uid, &zoneid);
8877
8878 return (dtrace_match(&pkey, priv, uid, zoneid, dtrace_ecb_create_enable,
8879 enab));
8880 }
8881
8882 /*
8883 * DTrace Helper Provider Functions
8884 */
8885 static void
8886 dtrace_dofattr2attr(dtrace_attribute_t *attr, const dof_attr_t dofattr)
8887 {
8888 attr->dtat_name = DOF_ATTR_NAME(dofattr);
8889 attr->dtat_data = DOF_ATTR_DATA(dofattr);
8890 attr->dtat_class = DOF_ATTR_CLASS(dofattr);
8891 }
8892
8893 static void
8894 dtrace_dofprov2hprov(dtrace_helper_provdesc_t *hprov,
8895 const dof_provider_t *dofprov, char *strtab)
8896 {
8897 hprov->dthpv_provname = strtab + dofprov->dofpv_name;
8898 dtrace_dofattr2attr(&hprov->dthpv_pattr.dtpa_provider,
8899 dofprov->dofpv_provattr);
8900 dtrace_dofattr2attr(&hprov->dthpv_pattr.dtpa_mod,
8901 dofprov->dofpv_modattr);
8902 dtrace_dofattr2attr(&hprov->dthpv_pattr.dtpa_func,
8903 dofprov->dofpv_funcattr);
8904 dtrace_dofattr2attr(&hprov->dthpv_pattr.dtpa_name,
8905 dofprov->dofpv_nameattr);
8906 dtrace_dofattr2attr(&hprov->dthpv_pattr.dtpa_args,
8907 dofprov->dofpv_argsattr);
8908 }
8909
8910 static void
8911 dtrace_helper_provide_one(dof_helper_t *dhp, dof_sec_t *sec, pid_t pid)
8912 {
8913 uintptr_t daddr = (uintptr_t)dhp->dofhp_dof;
8914 dof_hdr_t *dof = (dof_hdr_t *)daddr;
8915 dof_sec_t *str_sec, *prb_sec, *arg_sec, *off_sec, *enoff_sec;
8916 dof_provider_t *provider;
8917 dof_probe_t *probe;
8918 uint32_t *off, *enoff;
8919 uint8_t *arg;
8920 char *strtab;
8921 uint_t i, nprobes;
8922 dtrace_helper_provdesc_t dhpv;
8923 dtrace_helper_probedesc_t dhpb;
8924 dtrace_meta_t *meta = dtrace_meta_pid;
8925 dtrace_mops_t *mops = &meta->dtm_mops;
8926 void *parg;
8927
8928 provider = (dof_provider_t *)(uintptr_t)(daddr + sec->dofs_offset);
8929 str_sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff +
8930 provider->dofpv_strtab * dof->dofh_secsize);
8931 prb_sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff +
8932 provider->dofpv_probes * dof->dofh_secsize);
8933 arg_sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff +
8934 provider->dofpv_prargs * dof->dofh_secsize);
8935 off_sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff +
8936 provider->dofpv_proffs * dof->dofh_secsize);
8937
8938 strtab = (char *)(uintptr_t)(daddr + str_sec->dofs_offset);
8939 off = (uint32_t *)(uintptr_t)(daddr + off_sec->dofs_offset);
8940 arg = (uint8_t *)(uintptr_t)(daddr + arg_sec->dofs_offset);
8941 enoff = NULL;
8942
8943 /*
8944 * See dtrace_helper_provider_validate().
8945 */
8946 if (dof->dofh_ident[DOF_ID_VERSION] != DOF_VERSION_1 &&
8947 provider->dofpv_prenoffs != DOF_SECT_NONE) {
8948 enoff_sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff +
8949 provider->dofpv_prenoffs * dof->dofh_secsize);
8950 enoff = (uint32_t *)(uintptr_t)(daddr + enoff_sec->dofs_offset);
8951 }
8952
8953 nprobes = prb_sec->dofs_size / prb_sec->dofs_entsize;
8954
8955 /*
8956 * Create the provider.
8957 */
8958 dtrace_dofprov2hprov(&dhpv, provider, strtab);
8959
8960 if ((parg = mops->dtms_provide_pid(meta->dtm_arg, &dhpv, pid)) == NULL)
8961 return;
8962
8963 meta->dtm_count++;
8964
8965 /*
8966 * Create the probes.
8967 */
8968 for (i = 0; i < nprobes; i++) {
8969 probe = (dof_probe_t *)(uintptr_t)(daddr +
8970 prb_sec->dofs_offset + i * prb_sec->dofs_entsize);
8971
8972 dhpb.dthpb_mod = dhp->dofhp_mod;
8973 dhpb.dthpb_func = strtab + probe->dofpr_func;
8974 dhpb.dthpb_name = strtab + probe->dofpr_name;
8975 dhpb.dthpb_base = probe->dofpr_addr;
8976 dhpb.dthpb_offs = off + probe->dofpr_offidx;
8977 dhpb.dthpb_noffs = probe->dofpr_noffs;
8978 if (enoff != NULL) {
8979 dhpb.dthpb_enoffs = enoff + probe->dofpr_enoffidx;
8980 dhpb.dthpb_nenoffs = probe->dofpr_nenoffs;
8981 } else {
8982 dhpb.dthpb_enoffs = NULL;
8983 dhpb.dthpb_nenoffs = 0;
8984 }
8985 dhpb.dthpb_args = arg + probe->dofpr_argidx;
8986 dhpb.dthpb_nargc = probe->dofpr_nargc;
8987 dhpb.dthpb_xargc = probe->dofpr_xargc;
8988 dhpb.dthpb_ntypes = strtab + probe->dofpr_nargv;
8989 dhpb.dthpb_xtypes = strtab + probe->dofpr_xargv;
8990
8991 mops->dtms_create_probe(meta->dtm_arg, parg, &dhpb);
8992 }
8993 }
8994
8995 static void
8996 dtrace_helper_provide(dof_helper_t *dhp, pid_t pid)
8997 {
8998 uintptr_t daddr = (uintptr_t)dhp->dofhp_dof;
8999 dof_hdr_t *dof = (dof_hdr_t *)daddr;
9000 int i;
9001
9002 ASSERT(MUTEX_HELD(&dtrace_meta_lock));
9003
9004 for (i = 0; i < dof->dofh_secnum; i++) {
9005 dof_sec_t *sec = (dof_sec_t *)(uintptr_t)(daddr +
9006 dof->dofh_secoff + i * dof->dofh_secsize);
9007
9008 if (sec->dofs_type != DOF_SECT_PROVIDER)
9009 continue;
9010
9011 dtrace_helper_provide_one(dhp, sec, pid);
9012 }
9013
9014 /*
9015 * We may have just created probes, so we must now rematch against
9016 * any retained enablings. Note that this call will acquire both
9017 * cpu_lock and dtrace_lock; the fact that we are holding
9018 * dtrace_meta_lock now is what defines the ordering with respect to
9019 * these three locks.
9020 */
9021 dtrace_enabling_matchall();
9022 }
9023
9024 static void
9025 dtrace_helper_provider_remove_one(dof_helper_t *dhp, dof_sec_t *sec, pid_t pid)
9026 {
9027 uintptr_t daddr = (uintptr_t)dhp->dofhp_dof;
9028 dof_hdr_t *dof = (dof_hdr_t *)daddr;
9029 dof_sec_t *str_sec;
9030 dof_provider_t *provider;
9031 char *strtab;
9032 dtrace_helper_provdesc_t dhpv;
9033 dtrace_meta_t *meta = dtrace_meta_pid;
9034 dtrace_mops_t *mops = &meta->dtm_mops;
9035
9036 provider = (dof_provider_t *)(uintptr_t)(daddr + sec->dofs_offset);
9037 str_sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff +
9038 provider->dofpv_strtab * dof->dofh_secsize);
9039
9040 strtab = (char *)(uintptr_t)(daddr + str_sec->dofs_offset);
9041
9042 /*
9043 * Create the provider.
9044 */
9045 dtrace_dofprov2hprov(&dhpv, provider, strtab);
9046
9047 mops->dtms_remove_pid(meta->dtm_arg, &dhpv, pid);
9048
9049 meta->dtm_count--;
9050 }
9051
9052 static void
9053 dtrace_helper_provider_remove(dof_helper_t *dhp, pid_t pid)
9054 {
9055 uintptr_t daddr = (uintptr_t)dhp->dofhp_dof;
9056 dof_hdr_t *dof = (dof_hdr_t *)daddr;
9057 int i;
9058
9059 ASSERT(MUTEX_HELD(&dtrace_meta_lock));
9060
9061 for (i = 0; i < dof->dofh_secnum; i++) {
9062 dof_sec_t *sec = (dof_sec_t *)(uintptr_t)(daddr +
9063 dof->dofh_secoff + i * dof->dofh_secsize);
9064
9065 if (sec->dofs_type != DOF_SECT_PROVIDER)
9066 continue;
9067
9068 dtrace_helper_provider_remove_one(dhp, sec, pid);
9069 }
9070 }
9071
9072 /*
9073 * DTrace Meta Provider-to-Framework API Functions
9074 *
9075 * These functions implement the Meta Provider-to-Framework API, as described
9076 * in <sys/dtrace.h>.
9077 */
9078 int
9079 dtrace_meta_register(const char *name, const dtrace_mops_t *mops, void *arg,
9080 dtrace_meta_provider_id_t *idp)
9081 {
9082 dtrace_meta_t *meta;
9083 dtrace_helpers_t *help, *next;
9084 int i;
9085
9086 *idp = DTRACE_METAPROVNONE;
9087
9088 /*
9089 * We strictly don't need the name, but we hold onto it for
9090 * debuggability. All hail error queues!
9091 */
9092 if (name == NULL) {
9093 cmn_err(CE_WARN, "failed to register meta-provider: "
9094 "invalid name");
9095 return (EINVAL);
9096 }
9097
9098 if (mops == NULL ||
9099 mops->dtms_create_probe == NULL ||
9100 mops->dtms_provide_pid == NULL ||
9101 mops->dtms_remove_pid == NULL) {
9102 cmn_err(CE_WARN, "failed to register meta-register %s: "
9103 "invalid ops", name);
9104 return (EINVAL);
9105 }
9106
9107 meta = kmem_zalloc(sizeof (dtrace_meta_t), KM_SLEEP);
9108 meta->dtm_mops = *mops;
9109 meta->dtm_name = kmem_alloc(strlen(name) + 1, KM_SLEEP);
9110 (void) strcpy(meta->dtm_name, name);
9111 meta->dtm_arg = arg;
9112
9113 mutex_enter(&dtrace_meta_lock);
9114 mutex_enter(&dtrace_lock);
9115
9116 if (dtrace_meta_pid != NULL) {
9117 mutex_exit(&dtrace_lock);
9118 mutex_exit(&dtrace_meta_lock);
9119 cmn_err(CE_WARN, "failed to register meta-register %s: "
9120 "user-land meta-provider exists", name);
9121 kmem_free(meta->dtm_name, strlen(meta->dtm_name) + 1);
9122 kmem_free(meta, sizeof (dtrace_meta_t));
9123 return (EINVAL);
9124 }
9125
9126 dtrace_meta_pid = meta;
9127 *idp = (dtrace_meta_provider_id_t)meta;
9128
9129 /*
9130 * If there are providers and probes ready to go, pass them
9131 * off to the new meta provider now.
9132 */
9133
9134 help = dtrace_deferred_pid;
9135 dtrace_deferred_pid = NULL;
9136
9137 mutex_exit(&dtrace_lock);
9138
9139 while (help != NULL) {
9140 for (i = 0; i < help->dthps_nprovs; i++) {
9141 dtrace_helper_provide(&help->dthps_provs[i]->dthp_prov,
9142 help->dthps_pid);
9143 }
9144
9145 next = help->dthps_next;
9146 help->dthps_next = NULL;
9147 help->dthps_prev = NULL;
9148 help->dthps_deferred = 0;
9149 help = next;
9150 }
9151
9152 mutex_exit(&dtrace_meta_lock);
9153
9154 return (0);
9155 }
9156
9157 int
9158 dtrace_meta_unregister(dtrace_meta_provider_id_t id)
9159 {
9160 dtrace_meta_t **pp, *old = (dtrace_meta_t *)id;
9161
9162 mutex_enter(&dtrace_meta_lock);
9163 mutex_enter(&dtrace_lock);
9164
9165 if (old == dtrace_meta_pid) {
9166 pp = &dtrace_meta_pid;
9167 } else {
9168 panic("attempt to unregister non-existent "
9169 "dtrace meta-provider %p\n", (void *)old);
9170 }
9171
9172 if (old->dtm_count != 0) {
9173 mutex_exit(&dtrace_lock);
9174 mutex_exit(&dtrace_meta_lock);
9175 return (EBUSY);
9176 }
9177
9178 *pp = NULL;
9179
9180 mutex_exit(&dtrace_lock);
9181 mutex_exit(&dtrace_meta_lock);
9182
9183 kmem_free(old->dtm_name, strlen(old->dtm_name) + 1);
9184 kmem_free(old, sizeof (dtrace_meta_t));
9185
9186 return (0);
9187 }
9188
9189
9190 /*
9191 * DTrace DIF Object Functions
9192 */
9193 static int
9194 dtrace_difo_err(uint_t pc, const char *format, ...)
9195 {
9196 if (dtrace_err_verbose) {
9197 va_list alist;
9198
9199 (void) uprintf("dtrace DIF object error: [%u]: ", pc);
9200 va_start(alist, format);
9201 (void) vuprintf(format, alist);
9202 va_end(alist);
9203 }
9204
9205 #ifdef DTRACE_ERRDEBUG
9206 dtrace_errdebug(format);
9207 #endif
9208 return (1);
9209 }
9210
9211 /*
9212 * Validate a DTrace DIF object by checking the IR instructions. The following
9213 * rules are currently enforced by dtrace_difo_validate():
9214 *
9215 * 1. Each instruction must have a valid opcode
9216 * 2. Each register, string, variable, or subroutine reference must be valid
9217 * 3. No instruction can modify register %r0 (must be zero)
9218 * 4. All instruction reserved bits must be set to zero
9219 * 5. The last instruction must be a "ret" instruction
9220 * 6. All branch targets must reference a valid instruction _after_ the branch
9221 */
9222 static int
9223 dtrace_difo_validate(dtrace_difo_t *dp, dtrace_vstate_t *vstate, uint_t nregs,
9224 cred_t *cr)
9225 {
9226 int err = 0, i;
9227 int (*efunc)(uint_t pc, const char *, ...) = dtrace_difo_err;
9228 int kcheckload;
9229 uint_t pc;
9230 int maxglobal = -1, maxlocal = -1, maxtlocal = -1;
9231
9232 kcheckload = cr == NULL ||
9233 (vstate->dtvs_state->dts_cred.dcr_visible & DTRACE_CRV_KERNEL) == 0;
9234
9235 dp->dtdo_destructive = 0;
9236
9237 for (pc = 0; pc < dp->dtdo_len && err == 0; pc++) {
9238 dif_instr_t instr = dp->dtdo_buf[pc];
9239
9240 uint_t r1 = DIF_INSTR_R1(instr);
9241 uint_t r2 = DIF_INSTR_R2(instr);
9242 uint_t rd = DIF_INSTR_RD(instr);
9243 uint_t rs = DIF_INSTR_RS(instr);
9244 uint_t label = DIF_INSTR_LABEL(instr);
9245 uint_t v = DIF_INSTR_VAR(instr);
9246 uint_t subr = DIF_INSTR_SUBR(instr);
9247 uint_t type = DIF_INSTR_TYPE(instr);
9248 uint_t op = DIF_INSTR_OP(instr);
9249
9250 switch (op) {
9251 case DIF_OP_OR:
9252 case DIF_OP_XOR:
9253 case DIF_OP_AND:
9254 case DIF_OP_SLL:
9255 case DIF_OP_SRL:
9256 case DIF_OP_SRA:
9257 case DIF_OP_SUB:
9258 case DIF_OP_ADD:
9259 case DIF_OP_MUL:
9260 case DIF_OP_SDIV:
9261 case DIF_OP_UDIV:
9262 case DIF_OP_SREM:
9263 case DIF_OP_UREM:
9264 case DIF_OP_COPYS:
9265 if (r1 >= nregs)
9266 err += efunc(pc, "invalid register %u\n", r1);
9267 if (r2 >= nregs)
9268 err += efunc(pc, "invalid register %u\n", r2);
9269 if (rd >= nregs)
9270 err += efunc(pc, "invalid register %u\n", rd);
9271 if (rd == 0)
9272 err += efunc(pc, "cannot write to %r0\n");
9273 break;
9274 case DIF_OP_NOT:
9275 case DIF_OP_MOV:
9276 case DIF_OP_ALLOCS:
9277 if (r1 >= nregs)
9278 err += efunc(pc, "invalid register %u\n", r1);
9279 if (r2 != 0)
9280 err += efunc(pc, "non-zero reserved bits\n");
9281 if (rd >= nregs)
9282 err += efunc(pc, "invalid register %u\n", rd);
9283 if (rd == 0)
9284 err += efunc(pc, "cannot write to %r0\n");
9285 break;
9286 case DIF_OP_LDSB:
9287 case DIF_OP_LDSH:
9288 case DIF_OP_LDSW:
9289 case DIF_OP_LDUB:
9290 case DIF_OP_LDUH:
9291 case DIF_OP_LDUW:
9292 case DIF_OP_LDX:
9293 if (r1 >= nregs)
9294 err += efunc(pc, "invalid register %u\n", r1);
9295 if (r2 != 0)
9296 err += efunc(pc, "non-zero reserved bits\n");
9297 if (rd >= nregs)
9298 err += efunc(pc, "invalid register %u\n", rd);
9299 if (rd == 0)
9300 err += efunc(pc, "cannot write to %r0\n");
9301 if (kcheckload)
9302 dp->dtdo_buf[pc] = DIF_INSTR_LOAD(op +
9303 DIF_OP_RLDSB - DIF_OP_LDSB, r1, rd);
9304 break;
9305 case DIF_OP_RLDSB:
9306 case DIF_OP_RLDSH:
9307 case DIF_OP_RLDSW:
9308 case DIF_OP_RLDUB:
9309 case DIF_OP_RLDUH:
9310 case DIF_OP_RLDUW:
9311 case DIF_OP_RLDX:
9312 if (r1 >= nregs)
9313 err += efunc(pc, "invalid register %u\n", r1);
9314 if (r2 != 0)
9315 err += efunc(pc, "non-zero reserved bits\n");
9316 if (rd >= nregs)
9317 err += efunc(pc, "invalid register %u\n", rd);
9318 if (rd == 0)
9319 err += efunc(pc, "cannot write to %r0\n");
9320 break;
9321 case DIF_OP_ULDSB:
9322 case DIF_OP_ULDSH:
9323 case DIF_OP_ULDSW:
9324 case DIF_OP_ULDUB:
9325 case DIF_OP_ULDUH:
9326 case DIF_OP_ULDUW:
9327 case DIF_OP_ULDX:
9328 if (r1 >= nregs)
9329 err += efunc(pc, "invalid register %u\n", r1);
9330 if (r2 != 0)
9331 err += efunc(pc, "non-zero reserved bits\n");
9332 if (rd >= nregs)
9333 err += efunc(pc, "invalid register %u\n", rd);
9334 if (rd == 0)
9335 err += efunc(pc, "cannot write to %r0\n");
9336 break;
9337 case DIF_OP_STB:
9338 case DIF_OP_STH:
9339 case DIF_OP_STW:
9340 case DIF_OP_STX:
9341 if (r1 >= nregs)
9342 err += efunc(pc, "invalid register %u\n", r1);
9343 if (r2 != 0)
9344 err += efunc(pc, "non-zero reserved bits\n");
9345 if (rd >= nregs)
9346 err += efunc(pc, "invalid register %u\n", rd);
9347 if (rd == 0)
9348 err += efunc(pc, "cannot write to 0 address\n");
9349 break;
9350 case DIF_OP_CMP:
9351 case DIF_OP_SCMP:
9352 if (r1 >= nregs)
9353 err += efunc(pc, "invalid register %u\n", r1);
9354 if (r2 >= nregs)
9355 err += efunc(pc, "invalid register %u\n", r2);
9356 if (rd != 0)
9357 err += efunc(pc, "non-zero reserved bits\n");
9358 break;
9359 case DIF_OP_TST:
9360 if (r1 >= nregs)
9361 err += efunc(pc, "invalid register %u\n", r1);
9362 if (r2 != 0 || rd != 0)
9363 err += efunc(pc, "non-zero reserved bits\n");
9364 break;
9365 case DIF_OP_BA:
9366 case DIF_OP_BE:
9367 case DIF_OP_BNE:
9368 case DIF_OP_BG:
9369 case DIF_OP_BGU:
9370 case DIF_OP_BGE:
9371 case DIF_OP_BGEU:
9372 case DIF_OP_BL:
9373 case DIF_OP_BLU:
9374 case DIF_OP_BLE:
9375 case DIF_OP_BLEU:
9376 if (label >= dp->dtdo_len) {
9377 err += efunc(pc, "invalid branch target %u\n",
9378 label);
9379 }
9380 if (label <= pc) {
9381 err += efunc(pc, "backward branch to %u\n",
9382 label);
9383 }
9384 break;
9385 case DIF_OP_RET:
9386 if (r1 != 0 || r2 != 0)
9387 err += efunc(pc, "non-zero reserved bits\n");
9388 if (rd >= nregs)
9389 err += efunc(pc, "invalid register %u\n", rd);
9390 break;
9391 case DIF_OP_NOP:
9392 case DIF_OP_POPTS:
9393 case DIF_OP_FLUSHTS:
9394 if (r1 != 0 || r2 != 0 || rd != 0)
9395 err += efunc(pc, "non-zero reserved bits\n");
9396 break;
9397 case DIF_OP_SETX:
9398 if (DIF_INSTR_INTEGER(instr) >= dp->dtdo_intlen) {
9399 err += efunc(pc, "invalid integer ref %u\n",
9400 DIF_INSTR_INTEGER(instr));
9401 }
9402 if (rd >= nregs)
9403 err += efunc(pc, "invalid register %u\n", rd);
9404 if (rd == 0)
9405 err += efunc(pc, "cannot write to %r0\n");
9406 break;
9407 case DIF_OP_SETS:
9408 if (DIF_INSTR_STRING(instr) >= dp->dtdo_strlen) {
9409 err += efunc(pc, "invalid string ref %u\n",
9410 DIF_INSTR_STRING(instr));
9411 }
9412 if (rd >= nregs)
9413 err += efunc(pc, "invalid register %u\n", rd);
9414 if (rd == 0)
9415 err += efunc(pc, "cannot write to %r0\n");
9416 break;
9417 case DIF_OP_LDGA:
9418 case DIF_OP_LDTA:
9419 if (r1 > DIF_VAR_ARRAY_MAX)
9420 err += efunc(pc, "invalid array %u\n", r1);
9421 if (r2 >= nregs)
9422 err += efunc(pc, "invalid register %u\n", r2);
9423 if (rd >= nregs)
9424 err += efunc(pc, "invalid register %u\n", rd);
9425 if (rd == 0)
9426 err += efunc(pc, "cannot write to %r0\n");
9427 break;
9428 case DIF_OP_STGA:
9429 if (r1 > DIF_VAR_ARRAY_MAX)
9430 err += efunc(pc, "invalid array %u\n", r1);
9431 if (r2 >= nregs)
9432 err += efunc(pc, "invalid register %u\n", r2);
9433 if (rd >= nregs)
9434 err += efunc(pc, "invalid register %u\n", rd);
9435 dp->dtdo_destructive = 1;
9436 break;
9437 case DIF_OP_LDGS:
9438 case DIF_OP_LDTS:
9439 case DIF_OP_LDLS:
9440 case DIF_OP_LDGAA:
9441 case DIF_OP_LDTAA:
9442 if (v < DIF_VAR_OTHER_MIN || v > DIF_VAR_OTHER_MAX)
9443 err += efunc(pc, "invalid variable %u\n", v);
9444 if (rd >= nregs)
9445 err += efunc(pc, "invalid register %u\n", rd);
9446 if (rd == 0)
9447 err += efunc(pc, "cannot write to %r0\n");
9448 break;
9449 case DIF_OP_STGS:
9450 case DIF_OP_STTS:
9451 case DIF_OP_STLS:
9452 case DIF_OP_STGAA:
9453 case DIF_OP_STTAA:
9454 if (v < DIF_VAR_OTHER_UBASE || v > DIF_VAR_OTHER_MAX)
9455 err += efunc(pc, "invalid variable %u\n", v);
9456 if (rs >= nregs)
9457 err += efunc(pc, "invalid register %u\n", rd);
9458 break;
9459 case DIF_OP_CALL:
9460 if (subr > DIF_SUBR_MAX)
9461 err += efunc(pc, "invalid subr %u\n", subr);
9462 if (rd >= nregs)
9463 err += efunc(pc, "invalid register %u\n", rd);
9464 if (rd == 0)
9465 err += efunc(pc, "cannot write to %r0\n");
9466
9467 if (subr == DIF_SUBR_COPYOUT ||
9468 subr == DIF_SUBR_COPYOUTSTR) {
9469 dp->dtdo_destructive = 1;
9470 }
9471
9472 if (subr == DIF_SUBR_GETF) {
9473 /*
9474 * If we have a getf() we need to record that
9475 * in our state. Note that our state can be
9476 * NULL if this is a helper -- but in that
9477 * case, the call to getf() is itself illegal,
9478 * and will be caught (slightly later) when
9479 * the helper is validated.
9480 */
9481 if (vstate->dtvs_state != NULL)
9482 vstate->dtvs_state->dts_getf++;
9483 }
9484
9485 break;
9486 case DIF_OP_PUSHTR:
9487 if (type != DIF_TYPE_STRING && type != DIF_TYPE_CTF)
9488 err += efunc(pc, "invalid ref type %u\n", type);
9489 if (r2 >= nregs)
9490 err += efunc(pc, "invalid register %u\n", r2);
9491 if (rs >= nregs)
9492 err += efunc(pc, "invalid register %u\n", rs);
9493 break;
9494 case DIF_OP_PUSHTV:
9495 if (type != DIF_TYPE_CTF)
9496 err += efunc(pc, "invalid val type %u\n", type);
9497 if (r2 >= nregs)
9498 err += efunc(pc, "invalid register %u\n", r2);
9499 if (rs >= nregs)
9500 err += efunc(pc, "invalid register %u\n", rs);
9501 break;
9502 default:
9503 err += efunc(pc, "invalid opcode %u\n",
9504 DIF_INSTR_OP(instr));
9505 }
9506 }
9507
9508 if (dp->dtdo_len != 0 &&
9509 DIF_INSTR_OP(dp->dtdo_buf[dp->dtdo_len - 1]) != DIF_OP_RET) {
9510 err += efunc(dp->dtdo_len - 1,
9511 "expected 'ret' as last DIF instruction\n");
9512 }
9513
9514 if (!(dp->dtdo_rtype.dtdt_flags & (DIF_TF_BYREF | DIF_TF_BYUREF))) {
9515 /*
9516 * If we're not returning by reference, the size must be either
9517 * 0 or the size of one of the base types.
9518 */
9519 switch (dp->dtdo_rtype.dtdt_size) {
9520 case 0:
9521 case sizeof (uint8_t):
9522 case sizeof (uint16_t):
9523 case sizeof (uint32_t):
9524 case sizeof (uint64_t):
9525 break;
9526
9527 default:
9528 err += efunc(dp->dtdo_len - 1, "bad return size\n");
9529 }
9530 }
9531
9532 for (i = 0; i < dp->dtdo_varlen && err == 0; i++) {
9533 dtrace_difv_t *v = &dp->dtdo_vartab[i], *existing = NULL;
9534 dtrace_diftype_t *vt, *et;
9535 uint_t id, ndx;
9536
9537 if (v->dtdv_scope != DIFV_SCOPE_GLOBAL &&
9538 v->dtdv_scope != DIFV_SCOPE_THREAD &&
9539 v->dtdv_scope != DIFV_SCOPE_LOCAL) {
9540 err += efunc(i, "unrecognized variable scope %d\n",
9541 v->dtdv_scope);
9542 break;
9543 }
9544
9545 if (v->dtdv_kind != DIFV_KIND_ARRAY &&
9546 v->dtdv_kind != DIFV_KIND_SCALAR) {
9547 err += efunc(i, "unrecognized variable type %d\n",
9548 v->dtdv_kind);
9549 break;
9550 }
9551
9552 if ((id = v->dtdv_id) > DIF_VARIABLE_MAX) {
9553 err += efunc(i, "%d exceeds variable id limit\n", id);
9554 break;
9555 }
9556
9557 if (id < DIF_VAR_OTHER_UBASE)
9558 continue;
9559
9560 /*
9561 * For user-defined variables, we need to check that this
9562 * definition is identical to any previous definition that we
9563 * encountered.
9564 */
9565 ndx = id - DIF_VAR_OTHER_UBASE;
9566
9567 switch (v->dtdv_scope) {
9568 case DIFV_SCOPE_GLOBAL:
9569 if (maxglobal == -1 || ndx > maxglobal)
9570 maxglobal = ndx;
9571
9572 if (ndx < vstate->dtvs_nglobals) {
9573 dtrace_statvar_t *svar;
9574
9575 if ((svar = vstate->dtvs_globals[ndx]) != NULL)
9576 existing = &svar->dtsv_var;
9577 }
9578
9579 break;
9580
9581 case DIFV_SCOPE_THREAD:
9582 if (maxtlocal == -1 || ndx > maxtlocal)
9583 maxtlocal = ndx;
9584
9585 if (ndx < vstate->dtvs_ntlocals)
9586 existing = &vstate->dtvs_tlocals[ndx];
9587 break;
9588
9589 case DIFV_SCOPE_LOCAL:
9590 if (maxlocal == -1 || ndx > maxlocal)
9591 maxlocal = ndx;
9592
9593 if (ndx < vstate->dtvs_nlocals) {
9594 dtrace_statvar_t *svar;
9595
9596 if ((svar = vstate->dtvs_locals[ndx]) != NULL)
9597 existing = &svar->dtsv_var;
9598 }
9599
9600 break;
9601 }
9602
9603 vt = &v->dtdv_type;
9604
9605 if (vt->dtdt_flags & DIF_TF_BYREF) {
9606 if (vt->dtdt_size == 0) {
9607 err += efunc(i, "zero-sized variable\n");
9608 break;
9609 }
9610
9611 if ((v->dtdv_scope == DIFV_SCOPE_GLOBAL ||
9612 v->dtdv_scope == DIFV_SCOPE_LOCAL) &&
9613 vt->dtdt_size > dtrace_statvar_maxsize) {
9614 err += efunc(i, "oversized by-ref static\n");
9615 break;
9616 }
9617 }
9618
9619 if (existing == NULL || existing->dtdv_id == 0)
9620 continue;
9621
9622 ASSERT(existing->dtdv_id == v->dtdv_id);
9623 ASSERT(existing->dtdv_scope == v->dtdv_scope);
9624
9625 if (existing->dtdv_kind != v->dtdv_kind)
9626 err += efunc(i, "%d changed variable kind\n", id);
9627
9628 et = &existing->dtdv_type;
9629
9630 if (vt->dtdt_flags != et->dtdt_flags) {
9631 err += efunc(i, "%d changed variable type flags\n", id);
9632 break;
9633 }
9634
9635 if (vt->dtdt_size != 0 && vt->dtdt_size != et->dtdt_size) {
9636 err += efunc(i, "%d changed variable type size\n", id);
9637 break;
9638 }
9639 }
9640
9641 for (pc = 0; pc < dp->dtdo_len && err == 0; pc++) {
9642 dif_instr_t instr = dp->dtdo_buf[pc];
9643
9644 uint_t v = DIF_INSTR_VAR(instr);
9645 uint_t op = DIF_INSTR_OP(instr);
9646
9647 switch (op) {
9648 case DIF_OP_LDGS:
9649 case DIF_OP_LDGAA:
9650 case DIF_OP_STGS:
9651 case DIF_OP_STGAA:
9652 if (v > DIF_VAR_OTHER_UBASE + maxglobal)
9653 err += efunc(pc, "invalid variable %u\n", v);
9654 break;
9655 case DIF_OP_LDTS:
9656 case DIF_OP_LDTAA:
9657 case DIF_OP_STTS:
9658 case DIF_OP_STTAA:
9659 if (v > DIF_VAR_OTHER_UBASE + maxtlocal)
9660 err += efunc(pc, "invalid variable %u\n", v);
9661 break;
9662 case DIF_OP_LDLS:
9663 case DIF_OP_STLS:
9664 if (v > DIF_VAR_OTHER_UBASE + maxlocal)
9665 err += efunc(pc, "invalid variable %u\n", v);
9666 break;
9667 default:
9668 break;
9669 }
9670 }
9671
9672 return (err);
9673 }
9674
9675 /*
9676 * Validate a DTrace DIF object that it is to be used as a helper. Helpers
9677 * are much more constrained than normal DIFOs. Specifically, they may
9678 * not:
9679 *
9680 * 1. Make calls to subroutines other than copyin(), copyinstr() or
9681 * miscellaneous string routines
9682 * 2. Access DTrace variables other than the args[] array, and the
9683 * curthread, pid, ppid, tid, execname, zonename, uid and gid variables.
9684 * 3. Have thread-local variables.
9685 * 4. Have dynamic variables.
9686 */
9687 static int
9688 dtrace_difo_validate_helper(dtrace_difo_t *dp)
9689 {
9690 int (*efunc)(uint_t pc, const char *, ...) = dtrace_difo_err;
9691 int err = 0;
9692 uint_t pc;
9693
9694 for (pc = 0; pc < dp->dtdo_len; pc++) {
9695 dif_instr_t instr = dp->dtdo_buf[pc];
9696
9697 uint_t v = DIF_INSTR_VAR(instr);
9698 uint_t subr = DIF_INSTR_SUBR(instr);
9699 uint_t op = DIF_INSTR_OP(instr);
9700
9701 switch (op) {
9702 case DIF_OP_OR:
9703 case DIF_OP_XOR:
9704 case DIF_OP_AND:
9705 case DIF_OP_SLL:
9706 case DIF_OP_SRL:
9707 case DIF_OP_SRA:
9708 case DIF_OP_SUB:
9709 case DIF_OP_ADD:
9710 case DIF_OP_MUL:
9711 case DIF_OP_SDIV:
9712 case DIF_OP_UDIV:
9713 case DIF_OP_SREM:
9714 case DIF_OP_UREM:
9715 case DIF_OP_COPYS:
9716 case DIF_OP_NOT:
9717 case DIF_OP_MOV:
9718 case DIF_OP_RLDSB:
9719 case DIF_OP_RLDSH:
9720 case DIF_OP_RLDSW:
9721 case DIF_OP_RLDUB:
9722 case DIF_OP_RLDUH:
9723 case DIF_OP_RLDUW:
9724 case DIF_OP_RLDX:
9725 case DIF_OP_ULDSB:
9726 case DIF_OP_ULDSH:
9727 case DIF_OP_ULDSW:
9728 case DIF_OP_ULDUB:
9729 case DIF_OP_ULDUH:
9730 case DIF_OP_ULDUW:
9731 case DIF_OP_ULDX:
9732 case DIF_OP_STB:
9733 case DIF_OP_STH:
9734 case DIF_OP_STW:
9735 case DIF_OP_STX:
9736 case DIF_OP_ALLOCS:
9737 case DIF_OP_CMP:
9738 case DIF_OP_SCMP:
9739 case DIF_OP_TST:
9740 case DIF_OP_BA:
9741 case DIF_OP_BE:
9742 case DIF_OP_BNE:
9743 case DIF_OP_BG:
9744 case DIF_OP_BGU:
9745 case DIF_OP_BGE:
9746 case DIF_OP_BGEU:
9747 case DIF_OP_BL:
9748 case DIF_OP_BLU:
9749 case DIF_OP_BLE:
9750 case DIF_OP_BLEU:
9751 case DIF_OP_RET:
9752 case DIF_OP_NOP:
9753 case DIF_OP_POPTS:
9754 case DIF_OP_FLUSHTS:
9755 case DIF_OP_SETX:
9756 case DIF_OP_SETS:
9757 case DIF_OP_LDGA:
9758 case DIF_OP_LDLS:
9759 case DIF_OP_STGS:
9760 case DIF_OP_STLS:
9761 case DIF_OP_PUSHTR:
9762 case DIF_OP_PUSHTV:
9763 break;
9764
9765 case DIF_OP_LDGS:
9766 if (v >= DIF_VAR_OTHER_UBASE)
9767 break;
9768
9769 if (v >= DIF_VAR_ARG0 && v <= DIF_VAR_ARG9)
9770 break;
9771
9772 if (v == DIF_VAR_CURTHREAD || v == DIF_VAR_PID ||
9773 v == DIF_VAR_PPID || v == DIF_VAR_TID ||
9774 v == DIF_VAR_EXECNAME || v == DIF_VAR_ZONENAME ||
9775 v == DIF_VAR_UID || v == DIF_VAR_GID)
9776 break;
9777
9778 err += efunc(pc, "illegal variable %u\n", v);
9779 break;
9780
9781 case DIF_OP_LDTA:
9782 if (v < DIF_VAR_OTHER_UBASE) {
9783 err += efunc(pc, "illegal variable load\n");
9784 break;
9785 }
9786 /* FALLTHROUGH */
9787 case DIF_OP_LDTS:
9788 case DIF_OP_LDGAA:
9789 case DIF_OP_LDTAA:
9790 err += efunc(pc, "illegal dynamic variable load\n");
9791 break;
9792
9793 case DIF_OP_STGA:
9794 if (v < DIF_VAR_OTHER_UBASE) {
9795 err += efunc(pc, "illegal variable store\n");
9796 break;
9797 }
9798 /* FALLTHROUGH */
9799 case DIF_OP_STTS:
9800 case DIF_OP_STGAA:
9801 case DIF_OP_STTAA:
9802 err += efunc(pc, "illegal dynamic variable store\n");
9803 break;
9804
9805 case DIF_OP_CALL:
9806 if (subr == DIF_SUBR_ALLOCA ||
9807 subr == DIF_SUBR_BCOPY ||
9808 subr == DIF_SUBR_COPYIN ||
9809 subr == DIF_SUBR_COPYINTO ||
9810 subr == DIF_SUBR_COPYINSTR ||
9811 subr == DIF_SUBR_INDEX ||
9812 subr == DIF_SUBR_INET_NTOA ||
9813 subr == DIF_SUBR_INET_NTOA6 ||
9814 subr == DIF_SUBR_INET_NTOP ||
9815 subr == DIF_SUBR_JSON ||
9816 subr == DIF_SUBR_LLTOSTR ||
9817 subr == DIF_SUBR_STRTOLL ||
9818 subr == DIF_SUBR_RINDEX ||
9819 subr == DIF_SUBR_STRCHR ||
9820 subr == DIF_SUBR_STRJOIN ||
9821 subr == DIF_SUBR_STRRCHR ||
9822 subr == DIF_SUBR_STRSTR ||
9823 subr == DIF_SUBR_HTONS ||
9824 subr == DIF_SUBR_HTONL ||
9825 subr == DIF_SUBR_HTONLL ||
9826 subr == DIF_SUBR_NTOHS ||
9827 subr == DIF_SUBR_NTOHL ||
9828 subr == DIF_SUBR_NTOHLL)
9829 break;
9830
9831 err += efunc(pc, "invalid subr %u\n", subr);
9832 break;
9833
9834 default:
9835 err += efunc(pc, "invalid opcode %u\n",
9836 DIF_INSTR_OP(instr));
9837 }
9838 }
9839
9840 return (err);
9841 }
9842
9843 /*
9844 * Returns 1 if the expression in the DIF object can be cached on a per-thread
9845 * basis; 0 if not.
9846 */
9847 static int
9848 dtrace_difo_cacheable(dtrace_difo_t *dp)
9849 {
9850 int i;
9851
9852 if (dp == NULL)
9853 return (0);
9854
9855 for (i = 0; i < dp->dtdo_varlen; i++) {
9856 dtrace_difv_t *v = &dp->dtdo_vartab[i];
9857
9858 if (v->dtdv_scope != DIFV_SCOPE_GLOBAL)
9859 continue;
9860
9861 switch (v->dtdv_id) {
9862 case DIF_VAR_CURTHREAD:
9863 case DIF_VAR_PID:
9864 case DIF_VAR_TID:
9865 case DIF_VAR_EXECNAME:
9866 case DIF_VAR_ZONENAME:
9867 break;
9868
9869 default:
9870 return (0);
9871 }
9872 }
9873
9874 /*
9875 * This DIF object may be cacheable. Now we need to look for any
9876 * array loading instructions, any memory loading instructions, or
9877 * any stores to thread-local variables.
9878 */
9879 for (i = 0; i < dp->dtdo_len; i++) {
9880 uint_t op = DIF_INSTR_OP(dp->dtdo_buf[i]);
9881
9882 if ((op >= DIF_OP_LDSB && op <= DIF_OP_LDX) ||
9883 (op >= DIF_OP_ULDSB && op <= DIF_OP_ULDX) ||
9884 (op >= DIF_OP_RLDSB && op <= DIF_OP_RLDX) ||
9885 op == DIF_OP_LDGA || op == DIF_OP_STTS)
9886 return (0);
9887 }
9888
9889 return (1);
9890 }
9891
9892 static void
9893 dtrace_difo_hold(dtrace_difo_t *dp)
9894 {
9895 int i;
9896
9897 ASSERT(MUTEX_HELD(&dtrace_lock));
9898
9899 dp->dtdo_refcnt++;
9900 ASSERT(dp->dtdo_refcnt != 0);
9901
9902 /*
9903 * We need to check this DIF object for references to the variable
9904 * DIF_VAR_VTIMESTAMP.
9905 */
9906 for (i = 0; i < dp->dtdo_varlen; i++) {
9907 dtrace_difv_t *v = &dp->dtdo_vartab[i];
9908
9909 if (v->dtdv_id != DIF_VAR_VTIMESTAMP)
9910 continue;
9911
9912 if (dtrace_vtime_references++ == 0)
9913 dtrace_vtime_enable();
9914 }
9915 }
9916
9917 /*
9918 * This routine calculates the dynamic variable chunksize for a given DIF
9919 * object. The calculation is not fool-proof, and can probably be tricked by
9920 * malicious DIF -- but it works for all compiler-generated DIF. Because this
9921 * calculation is likely imperfect, dtrace_dynvar() is able to gracefully fail
9922 * if a dynamic variable size exceeds the chunksize.
9923 */
9924 static void
9925 dtrace_difo_chunksize(dtrace_difo_t *dp, dtrace_vstate_t *vstate)
9926 {
9927 uint64_t sval;
9928 dtrace_key_t tupregs[DIF_DTR_NREGS + 2]; /* +2 for thread and id */
9929 const dif_instr_t *text = dp->dtdo_buf;
9930 uint_t pc, srd = 0;
9931 uint_t ttop = 0;
9932 size_t size, ksize;
9933 uint_t id, i;
9934
9935 for (pc = 0; pc < dp->dtdo_len; pc++) {
9936 dif_instr_t instr = text[pc];
9937 uint_t op = DIF_INSTR_OP(instr);
9938 uint_t rd = DIF_INSTR_RD(instr);
9939 uint_t r1 = DIF_INSTR_R1(instr);
9940 uint_t nkeys = 0;
9941 uchar_t scope;
9942
9943 dtrace_key_t *key = tupregs;
9944
9945 switch (op) {
9946 case DIF_OP_SETX:
9947 sval = dp->dtdo_inttab[DIF_INSTR_INTEGER(instr)];
9948 srd = rd;
9949 continue;
9950
9951 case DIF_OP_STTS:
9952 key = &tupregs[DIF_DTR_NREGS];
9953 key[0].dttk_size = 0;
9954 key[1].dttk_size = 0;
9955 nkeys = 2;
9956 scope = DIFV_SCOPE_THREAD;
9957 break;
9958
9959 case DIF_OP_STGAA:
9960 case DIF_OP_STTAA:
9961 nkeys = ttop;
9962
9963 if (DIF_INSTR_OP(instr) == DIF_OP_STTAA)
9964 key[nkeys++].dttk_size = 0;
9965
9966 key[nkeys++].dttk_size = 0;
9967
9968 if (op == DIF_OP_STTAA) {
9969 scope = DIFV_SCOPE_THREAD;
9970 } else {
9971 scope = DIFV_SCOPE_GLOBAL;
9972 }
9973
9974 break;
9975
9976 case DIF_OP_PUSHTR:
9977 if (ttop == DIF_DTR_NREGS)
9978 return;
9979
9980 if ((srd == 0 || sval == 0) && r1 == DIF_TYPE_STRING) {
9981 /*
9982 * If the register for the size of the "pushtr"
9983 * is %r0 (or the value is 0) and the type is
9984 * a string, we'll use the system-wide default
9985 * string size.
9986 */
9987 tupregs[ttop++].dttk_size =
9988 dtrace_strsize_default;
9989 } else {
9990 if (srd == 0)
9991 return;
9992
9993 if (sval > LONG_MAX)
9994 return;
9995
9996 tupregs[ttop++].dttk_size = sval;
9997 }
9998
9999 break;
10000
10001 case DIF_OP_PUSHTV:
10002 if (ttop == DIF_DTR_NREGS)
10003 return;
10004
10005 tupregs[ttop++].dttk_size = 0;
10006 break;
10007
10008 case DIF_OP_FLUSHTS:
10009 ttop = 0;
10010 break;
10011
10012 case DIF_OP_POPTS:
10013 if (ttop != 0)
10014 ttop--;
10015 break;
10016 }
10017
10018 sval = 0;
10019 srd = 0;
10020
10021 if (nkeys == 0)
10022 continue;
10023
10024 /*
10025 * We have a dynamic variable allocation; calculate its size.
10026 */
10027 for (ksize = 0, i = 0; i < nkeys; i++)
10028 ksize += P2ROUNDUP(key[i].dttk_size, sizeof (uint64_t));
10029
10030 size = sizeof (dtrace_dynvar_t);
10031 size += sizeof (dtrace_key_t) * (nkeys - 1);
10032 size += ksize;
10033
10034 /*
10035 * Now we need to determine the size of the stored data.
10036 */
10037 id = DIF_INSTR_VAR(instr);
10038
10039 for (i = 0; i < dp->dtdo_varlen; i++) {
10040 dtrace_difv_t *v = &dp->dtdo_vartab[i];
10041
10042 if (v->dtdv_id == id && v->dtdv_scope == scope) {
10043 size += v->dtdv_type.dtdt_size;
10044 break;
10045 }
10046 }
10047
10048 if (i == dp->dtdo_varlen)
10049 return;
10050
10051 /*
10052 * We have the size. If this is larger than the chunk size
10053 * for our dynamic variable state, reset the chunk size.
10054 */
10055 size = P2ROUNDUP(size, sizeof (uint64_t));
10056
10057 /*
10058 * Before setting the chunk size, check that we're not going
10059 * to set it to a negative value...
10060 */
10061 if (size > LONG_MAX)
10062 return;
10063
10064 /*
10065 * ...and make certain that we didn't badly overflow.
10066 */
10067 if (size < ksize || size < sizeof (dtrace_dynvar_t))
10068 return;
10069
10070 if (size > vstate->dtvs_dynvars.dtds_chunksize)
10071 vstate->dtvs_dynvars.dtds_chunksize = size;
10072 }
10073 }
10074
10075 static void
10076 dtrace_difo_init(dtrace_difo_t *dp, dtrace_vstate_t *vstate)
10077 {
10078 int i, oldsvars, osz, nsz, otlocals, ntlocals;
10079 uint_t id;
10080
10081 ASSERT(MUTEX_HELD(&dtrace_lock));
10082 ASSERT(dp->dtdo_buf != NULL && dp->dtdo_len != 0);
10083
10084 for (i = 0; i < dp->dtdo_varlen; i++) {
10085 dtrace_difv_t *v = &dp->dtdo_vartab[i];
10086 dtrace_statvar_t *svar, ***svarp;
10087 size_t dsize = 0;
10088 uint8_t scope = v->dtdv_scope;
10089 int *np;
10090
10091 if ((id = v->dtdv_id) < DIF_VAR_OTHER_UBASE)
10092 continue;
10093
10094 id -= DIF_VAR_OTHER_UBASE;
10095
10096 switch (scope) {
10097 case DIFV_SCOPE_THREAD:
10098 while (id >= (otlocals = vstate->dtvs_ntlocals)) {
10099 dtrace_difv_t *tlocals;
10100
10101 if ((ntlocals = (otlocals << 1)) == 0)
10102 ntlocals = 1;
10103
10104 osz = otlocals * sizeof (dtrace_difv_t);
10105 nsz = ntlocals * sizeof (dtrace_difv_t);
10106
10107 tlocals = kmem_zalloc(nsz, KM_SLEEP);
10108
10109 if (osz != 0) {
10110 bcopy(vstate->dtvs_tlocals,
10111 tlocals, osz);
10112 kmem_free(vstate->dtvs_tlocals, osz);
10113 }
10114
10115 vstate->dtvs_tlocals = tlocals;
10116 vstate->dtvs_ntlocals = ntlocals;
10117 }
10118
10119 vstate->dtvs_tlocals[id] = *v;
10120 continue;
10121
10122 case DIFV_SCOPE_LOCAL:
10123 np = &vstate->dtvs_nlocals;
10124 svarp = &vstate->dtvs_locals;
10125
10126 if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF)
10127 dsize = NCPU * (v->dtdv_type.dtdt_size +
10128 sizeof (uint64_t));
10129 else
10130 dsize = NCPU * sizeof (uint64_t);
10131
10132 break;
10133
10134 case DIFV_SCOPE_GLOBAL:
10135 np = &vstate->dtvs_nglobals;
10136 svarp = &vstate->dtvs_globals;
10137
10138 if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF)
10139 dsize = v->dtdv_type.dtdt_size +
10140 sizeof (uint64_t);
10141
10142 break;
10143
10144 default:
10145 ASSERT(0);
10146 }
10147
10148 while (id >= (oldsvars = *np)) {
10149 dtrace_statvar_t **statics;
10150 int newsvars, oldsize, newsize;
10151
10152 if ((newsvars = (oldsvars << 1)) == 0)
10153 newsvars = 1;
10154
10155 oldsize = oldsvars * sizeof (dtrace_statvar_t *);
10156 newsize = newsvars * sizeof (dtrace_statvar_t *);
10157
10158 statics = kmem_zalloc(newsize, KM_SLEEP);
10159
10160 if (oldsize != 0) {
10161 bcopy(*svarp, statics, oldsize);
10162 kmem_free(*svarp, oldsize);
10163 }
10164
10165 *svarp = statics;
10166 *np = newsvars;
10167 }
10168
10169 if ((svar = (*svarp)[id]) == NULL) {
10170 svar = kmem_zalloc(sizeof (dtrace_statvar_t), KM_SLEEP);
10171 svar->dtsv_var = *v;
10172
10173 if ((svar->dtsv_size = dsize) != 0) {
10174 svar->dtsv_data = (uint64_t)(uintptr_t)
10175 kmem_zalloc(dsize, KM_SLEEP);
10176 }
10177
10178 (*svarp)[id] = svar;
10179 }
10180
10181 svar->dtsv_refcnt++;
10182 }
10183
10184 dtrace_difo_chunksize(dp, vstate);
10185 dtrace_difo_hold(dp);
10186 }
10187
10188 static dtrace_difo_t *
10189 dtrace_difo_duplicate(dtrace_difo_t *dp, dtrace_vstate_t *vstate)
10190 {
10191 dtrace_difo_t *new;
10192 size_t sz;
10193
10194 ASSERT(dp->dtdo_buf != NULL);
10195 ASSERT(dp->dtdo_refcnt != 0);
10196
10197 new = kmem_zalloc(sizeof (dtrace_difo_t), KM_SLEEP);
10198
10199 ASSERT(dp->dtdo_buf != NULL);
10200 sz = dp->dtdo_len * sizeof (dif_instr_t);
10201 new->dtdo_buf = kmem_alloc(sz, KM_SLEEP);
10202 bcopy(dp->dtdo_buf, new->dtdo_buf, sz);
10203 new->dtdo_len = dp->dtdo_len;
10204
10205 if (dp->dtdo_strtab != NULL) {
10206 ASSERT(dp->dtdo_strlen != 0);
10207 new->dtdo_strtab = kmem_alloc(dp->dtdo_strlen, KM_SLEEP);
10208 bcopy(dp->dtdo_strtab, new->dtdo_strtab, dp->dtdo_strlen);
10209 new->dtdo_strlen = dp->dtdo_strlen;
10210 }
10211
10212 if (dp->dtdo_inttab != NULL) {
10213 ASSERT(dp->dtdo_intlen != 0);
10214 sz = dp->dtdo_intlen * sizeof (uint64_t);
10215 new->dtdo_inttab = kmem_alloc(sz, KM_SLEEP);
10216 bcopy(dp->dtdo_inttab, new->dtdo_inttab, sz);
10217 new->dtdo_intlen = dp->dtdo_intlen;
10218 }
10219
10220 if (dp->dtdo_vartab != NULL) {
10221 ASSERT(dp->dtdo_varlen != 0);
10222 sz = dp->dtdo_varlen * sizeof (dtrace_difv_t);
10223 new->dtdo_vartab = kmem_alloc(sz, KM_SLEEP);
10224 bcopy(dp->dtdo_vartab, new->dtdo_vartab, sz);
10225 new->dtdo_varlen = dp->dtdo_varlen;
10226 }
10227
10228 dtrace_difo_init(new, vstate);
10229 return (new);
10230 }
10231
10232 static void
10233 dtrace_difo_destroy(dtrace_difo_t *dp, dtrace_vstate_t *vstate)
10234 {
10235 int i;
10236
10237 ASSERT(dp->dtdo_refcnt == 0);
10238
10239 for (i = 0; i < dp->dtdo_varlen; i++) {
10240 dtrace_difv_t *v = &dp->dtdo_vartab[i];
10241 dtrace_statvar_t *svar, **svarp;
10242 uint_t id;
10243 uint8_t scope = v->dtdv_scope;
10244 int *np;
10245
10246 switch (scope) {
10247 case DIFV_SCOPE_THREAD:
10248 continue;
10249
10250 case DIFV_SCOPE_LOCAL:
10251 np = &vstate->dtvs_nlocals;
10252 svarp = vstate->dtvs_locals;
10253 break;
10254
10255 case DIFV_SCOPE_GLOBAL:
10256 np = &vstate->dtvs_nglobals;
10257 svarp = vstate->dtvs_globals;
10258 break;
10259
10260 default:
10261 ASSERT(0);
10262 }
10263
10264 if ((id = v->dtdv_id) < DIF_VAR_OTHER_UBASE)
10265 continue;
10266
10267 id -= DIF_VAR_OTHER_UBASE;
10268 ASSERT(id < *np);
10269
10270 svar = svarp[id];
10271 ASSERT(svar != NULL);
10272 ASSERT(svar->dtsv_refcnt > 0);
10273
10274 if (--svar->dtsv_refcnt > 0)
10275 continue;
10276
10277 if (svar->dtsv_size != 0) {
10278 ASSERT(svar->dtsv_data != NULL);
10279 kmem_free((void *)(uintptr_t)svar->dtsv_data,
10280 svar->dtsv_size);
10281 }
10282
10283 kmem_free(svar, sizeof (dtrace_statvar_t));
10284 svarp[id] = NULL;
10285 }
10286
10287 kmem_free(dp->dtdo_buf, dp->dtdo_len * sizeof (dif_instr_t));
10288 kmem_free(dp->dtdo_inttab, dp->dtdo_intlen * sizeof (uint64_t));
10289 kmem_free(dp->dtdo_strtab, dp->dtdo_strlen);
10290 kmem_free(dp->dtdo_vartab, dp->dtdo_varlen * sizeof (dtrace_difv_t));
10291
10292 kmem_free(dp, sizeof (dtrace_difo_t));
10293 }
10294
10295 static void
10296 dtrace_difo_release(dtrace_difo_t *dp, dtrace_vstate_t *vstate)
10297 {
10298 int i;
10299
10300 ASSERT(MUTEX_HELD(&dtrace_lock));
10301 ASSERT(dp->dtdo_refcnt != 0);
10302
10303 for (i = 0; i < dp->dtdo_varlen; i++) {
10304 dtrace_difv_t *v = &dp->dtdo_vartab[i];
10305
10306 if (v->dtdv_id != DIF_VAR_VTIMESTAMP)
10307 continue;
10308
10309 ASSERT(dtrace_vtime_references > 0);
10310 if (--dtrace_vtime_references == 0)
10311 dtrace_vtime_disable();
10312 }
10313
10314 if (--dp->dtdo_refcnt == 0)
10315 dtrace_difo_destroy(dp, vstate);
10316 }
10317
10318 /*
10319 * DTrace Format Functions
10320 */
10321 static uint16_t
10322 dtrace_format_add(dtrace_state_t *state, char *str)
10323 {
10324 char *fmt, **new;
10325 uint16_t ndx, len = strlen(str) + 1;
10326
10327 fmt = kmem_zalloc(len, KM_SLEEP);
10328 bcopy(str, fmt, len);
10329
10330 for (ndx = 0; ndx < state->dts_nformats; ndx++) {
10331 if (state->dts_formats[ndx] == NULL) {
10332 state->dts_formats[ndx] = fmt;
10333 return (ndx + 1);
10334 }
10335 }
10336
10337 if (state->dts_nformats == USHRT_MAX) {
10338 /*
10339 * This is only likely if a denial-of-service attack is being
10340 * attempted. As such, it's okay to fail silently here.
10341 */
10342 kmem_free(fmt, len);
10343 return (0);
10344 }
10345
10346 /*
10347 * For simplicity, we always resize the formats array to be exactly the
10348 * number of formats.
10349 */
10350 ndx = state->dts_nformats++;
10351 new = kmem_alloc((ndx + 1) * sizeof (char *), KM_SLEEP);
10352
10353 if (state->dts_formats != NULL) {
10354 ASSERT(ndx != 0);
10355 bcopy(state->dts_formats, new, ndx * sizeof (char *));
10356 kmem_free(state->dts_formats, ndx * sizeof (char *));
10357 }
10358
10359 state->dts_formats = new;
10360 state->dts_formats[ndx] = fmt;
10361
10362 return (ndx + 1);
10363 }
10364
10365 static void
10366 dtrace_format_remove(dtrace_state_t *state, uint16_t format)
10367 {
10368 char *fmt;
10369
10370 ASSERT(state->dts_formats != NULL);
10371 ASSERT(format <= state->dts_nformats);
10372 ASSERT(state->dts_formats[format - 1] != NULL);
10373
10374 fmt = state->dts_formats[format - 1];
10375 kmem_free(fmt, strlen(fmt) + 1);
10376 state->dts_formats[format - 1] = NULL;
10377 }
10378
10379 static void
10380 dtrace_format_destroy(dtrace_state_t *state)
10381 {
10382 int i;
10383
10384 if (state->dts_nformats == 0) {
10385 ASSERT(state->dts_formats == NULL);
10386 return;
10387 }
10388
10389 ASSERT(state->dts_formats != NULL);
10390
10391 for (i = 0; i < state->dts_nformats; i++) {
10392 char *fmt = state->dts_formats[i];
10393
10394 if (fmt == NULL)
10395 continue;
10396
10397 kmem_free(fmt, strlen(fmt) + 1);
10398 }
10399
10400 kmem_free(state->dts_formats, state->dts_nformats * sizeof (char *));
10401 state->dts_nformats = 0;
10402 state->dts_formats = NULL;
10403 }
10404
10405 /*
10406 * DTrace Predicate Functions
10407 */
10408 static dtrace_predicate_t *
10409 dtrace_predicate_create(dtrace_difo_t *dp)
10410 {
10411 dtrace_predicate_t *pred;
10412
10413 ASSERT(MUTEX_HELD(&dtrace_lock));
10414 ASSERT(dp->dtdo_refcnt != 0);
10415
10416 pred = kmem_zalloc(sizeof (dtrace_predicate_t), KM_SLEEP);
10417 pred->dtp_difo = dp;
10418 pred->dtp_refcnt = 1;
10419
10420 if (!dtrace_difo_cacheable(dp))
10421 return (pred);
10422
10423 if (dtrace_predcache_id == DTRACE_CACHEIDNONE) {
10424 /*
10425 * This is only theoretically possible -- we have had 2^32
10426 * cacheable predicates on this machine. We cannot allow any
10427 * more predicates to become cacheable: as unlikely as it is,
10428 * there may be a thread caching a (now stale) predicate cache
10429 * ID. (N.B.: the temptation is being successfully resisted to
10430 * have this cmn_err() "Holy shit -- we executed this code!")
10431 */
10432 return (pred);
10433 }
10434
10435 pred->dtp_cacheid = dtrace_predcache_id++;
10436
10437 return (pred);
10438 }
10439
10440 static void
10441 dtrace_predicate_hold(dtrace_predicate_t *pred)
10442 {
10443 ASSERT(MUTEX_HELD(&dtrace_lock));
10444 ASSERT(pred->dtp_difo != NULL && pred->dtp_difo->dtdo_refcnt != 0);
10445 ASSERT(pred->dtp_refcnt > 0);
10446
10447 pred->dtp_refcnt++;
10448 }
10449
10450 static void
10451 dtrace_predicate_release(dtrace_predicate_t *pred, dtrace_vstate_t *vstate)
10452 {
10453 dtrace_difo_t *dp = pred->dtp_difo;
10454
10455 ASSERT(MUTEX_HELD(&dtrace_lock));
10456 ASSERT(dp != NULL && dp->dtdo_refcnt != 0);
10457 ASSERT(pred->dtp_refcnt > 0);
10458
10459 if (--pred->dtp_refcnt == 0) {
10460 dtrace_difo_release(pred->dtp_difo, vstate);
10461 kmem_free(pred, sizeof (dtrace_predicate_t));
10462 }
10463 }
10464
10465 /*
10466 * DTrace Action Description Functions
10467 */
10468 static dtrace_actdesc_t *
10469 dtrace_actdesc_create(dtrace_actkind_t kind, uint32_t ntuple,
10470 uint64_t uarg, uint64_t arg)
10471 {
10472 dtrace_actdesc_t *act;
10473
10474 ASSERT(!DTRACEACT_ISPRINTFLIKE(kind) || (arg != NULL &&
10475 arg >= KERNELBASE) || (arg == NULL && kind == DTRACEACT_PRINTA));
10476
10477 act = kmem_zalloc(sizeof (dtrace_actdesc_t), KM_SLEEP);
10478 act->dtad_kind = kind;
10479 act->dtad_ntuple = ntuple;
10480 act->dtad_uarg = uarg;
10481 act->dtad_arg = arg;
10482 act->dtad_refcnt = 1;
10483
10484 return (act);
10485 }
10486
10487 static void
10488 dtrace_actdesc_hold(dtrace_actdesc_t *act)
10489 {
10490 ASSERT(act->dtad_refcnt >= 1);
10491 act->dtad_refcnt++;
10492 }
10493
10494 static void
10495 dtrace_actdesc_release(dtrace_actdesc_t *act, dtrace_vstate_t *vstate)
10496 {
10497 dtrace_actkind_t kind = act->dtad_kind;
10498 dtrace_difo_t *dp;
10499
10500 ASSERT(act->dtad_refcnt >= 1);
10501
10502 if (--act->dtad_refcnt != 0)
10503 return;
10504
10505 if ((dp = act->dtad_difo) != NULL)
10506 dtrace_difo_release(dp, vstate);
10507
10508 if (DTRACEACT_ISPRINTFLIKE(kind)) {
10509 char *str = (char *)(uintptr_t)act->dtad_arg;
10510
10511 ASSERT((str != NULL && (uintptr_t)str >= KERNELBASE) ||
10512 (str == NULL && act->dtad_kind == DTRACEACT_PRINTA));
10513
10514 if (str != NULL)
10515 kmem_free(str, strlen(str) + 1);
10516 }
10517
10518 kmem_free(act, sizeof (dtrace_actdesc_t));
10519 }
10520
10521 /*
10522 * DTrace ECB Functions
10523 */
10524 static dtrace_ecb_t *
10525 dtrace_ecb_add(dtrace_state_t *state, dtrace_probe_t *probe)
10526 {
10527 dtrace_ecb_t *ecb;
10528 dtrace_epid_t epid;
10529
10530 ASSERT(MUTEX_HELD(&dtrace_lock));
10531
10532 ecb = kmem_zalloc(sizeof (dtrace_ecb_t), KM_SLEEP);
10533 ecb->dte_predicate = NULL;
10534 ecb->dte_probe = probe;
10535
10536 /*
10537 * The default size is the size of the default action: recording
10538 * the header.
10539 */
10540 ecb->dte_size = ecb->dte_needed = sizeof (dtrace_rechdr_t);
10541 ecb->dte_alignment = sizeof (dtrace_epid_t);
10542
10543 epid = state->dts_epid++;
10544
10545 if (epid - 1 >= state->dts_necbs) {
10546 dtrace_ecb_t **oecbs = state->dts_ecbs, **ecbs;
10547 int necbs = state->dts_necbs << 1;
10548
10549 ASSERT(epid == state->dts_necbs + 1);
10550
10551 if (necbs == 0) {
10552 ASSERT(oecbs == NULL);
10553 necbs = 1;
10554 }
10555
10556 ecbs = kmem_zalloc(necbs * sizeof (*ecbs), KM_SLEEP);
10557
10558 if (oecbs != NULL)
10559 bcopy(oecbs, ecbs, state->dts_necbs * sizeof (*ecbs));
10560
10561 dtrace_membar_producer();
10562 state->dts_ecbs = ecbs;
10563
10564 if (oecbs != NULL) {
10565 /*
10566 * If this state is active, we must dtrace_sync()
10567 * before we can free the old dts_ecbs array: we're
10568 * coming in hot, and there may be active ring
10569 * buffer processing (which indexes into the dts_ecbs
10570 * array) on another CPU.
10571 */
10572 if (state->dts_activity != DTRACE_ACTIVITY_INACTIVE)
10573 dtrace_sync();
10574
10575 kmem_free(oecbs, state->dts_necbs * sizeof (*ecbs));
10576 }
10577
10578 dtrace_membar_producer();
10579 state->dts_necbs = necbs;
10580 }
10581
10582 ecb->dte_state = state;
10583
10584 ASSERT(state->dts_ecbs[epid - 1] == NULL);
10585 dtrace_membar_producer();
10586 state->dts_ecbs[(ecb->dte_epid = epid) - 1] = ecb;
10587
10588 return (ecb);
10589 }
10590
10591 static int
10592 dtrace_ecb_enable(dtrace_ecb_t *ecb)
10593 {
10594 dtrace_probe_t *probe = ecb->dte_probe;
10595
10596 ASSERT(MUTEX_HELD(&cpu_lock));
10597 ASSERT(MUTEX_HELD(&dtrace_lock));
10598 ASSERT(ecb->dte_next == NULL);
10599
10600 if (probe == NULL) {
10601 /*
10602 * This is the NULL probe -- there's nothing to do.
10603 */
10604 return (0);
10605 }
10606
10607 if (probe->dtpr_ecb == NULL) {
10608 dtrace_provider_t *prov = probe->dtpr_provider;
10609
10610 /*
10611 * We're the first ECB on this probe.
10612 */
10613 probe->dtpr_ecb = probe->dtpr_ecb_last = ecb;
10614
10615 if (ecb->dte_predicate != NULL)
10616 probe->dtpr_predcache = ecb->dte_predicate->dtp_cacheid;
10617
10618 return (prov->dtpv_pops.dtps_enable(prov->dtpv_arg,
10619 probe->dtpr_id, probe->dtpr_arg));
10620 } else {
10621 /*
10622 * This probe is already active. Swing the last pointer to
10623 * point to the new ECB, and issue a dtrace_sync() to assure
10624 * that all CPUs have seen the change.
10625 */
10626 ASSERT(probe->dtpr_ecb_last != NULL);
10627 probe->dtpr_ecb_last->dte_next = ecb;
10628 probe->dtpr_ecb_last = ecb;
10629 probe->dtpr_predcache = 0;
10630
10631 dtrace_sync();
10632 return (0);
10633 }
10634 }
10635
10636 static int
10637 dtrace_ecb_resize(dtrace_ecb_t *ecb)
10638 {
10639 dtrace_action_t *act;
10640 uint32_t curneeded = UINT32_MAX;
10641 uint32_t aggbase = UINT32_MAX;
10642
10643 /*
10644 * If we record anything, we always record the dtrace_rechdr_t. (And
10645 * we always record it first.)
10646 */
10647 ecb->dte_size = sizeof (dtrace_rechdr_t);
10648 ecb->dte_alignment = sizeof (dtrace_epid_t);
10649
10650 for (act = ecb->dte_action; act != NULL; act = act->dta_next) {
10651 dtrace_recdesc_t *rec = &act->dta_rec;
10652 ASSERT(rec->dtrd_size > 0 || rec->dtrd_alignment == 1);
10653
10654 ecb->dte_alignment = MAX(ecb->dte_alignment,
10655 rec->dtrd_alignment);
10656
10657 if (DTRACEACT_ISAGG(act->dta_kind)) {
10658 dtrace_aggregation_t *agg = (dtrace_aggregation_t *)act;
10659
10660 ASSERT(rec->dtrd_size != 0);
10661 ASSERT(agg->dtag_first != NULL);
10662 ASSERT(act->dta_prev->dta_intuple);
10663 ASSERT(aggbase != UINT32_MAX);
10664 ASSERT(curneeded != UINT32_MAX);
10665
10666 agg->dtag_base = aggbase;
10667
10668 curneeded = P2ROUNDUP(curneeded, rec->dtrd_alignment);
10669 rec->dtrd_offset = curneeded;
10670 if (curneeded + rec->dtrd_size < curneeded)
10671 return (EINVAL);
10672 curneeded += rec->dtrd_size;
10673 ecb->dte_needed = MAX(ecb->dte_needed, curneeded);
10674
10675 aggbase = UINT32_MAX;
10676 curneeded = UINT32_MAX;
10677 } else if (act->dta_intuple) {
10678 if (curneeded == UINT32_MAX) {
10679 /*
10680 * This is the first record in a tuple. Align
10681 * curneeded to be at offset 4 in an 8-byte
10682 * aligned block.
10683 */
10684 ASSERT(act->dta_prev == NULL ||
10685 !act->dta_prev->dta_intuple);
10686 ASSERT3U(aggbase, ==, UINT32_MAX);
10687 curneeded = P2PHASEUP(ecb->dte_size,
10688 sizeof (uint64_t), sizeof (dtrace_aggid_t));
10689
10690 aggbase = curneeded - sizeof (dtrace_aggid_t);
10691 ASSERT(IS_P2ALIGNED(aggbase,
10692 sizeof (uint64_t)));
10693 }
10694 curneeded = P2ROUNDUP(curneeded, rec->dtrd_alignment);
10695 rec->dtrd_offset = curneeded;
10696 if (curneeded + rec->dtrd_size < curneeded)
10697 return (EINVAL);
10698 curneeded += rec->dtrd_size;
10699 } else {
10700 /* tuples must be followed by an aggregation */
10701 ASSERT(act->dta_prev == NULL ||
10702 !act->dta_prev->dta_intuple);
10703
10704 ecb->dte_size = P2ROUNDUP(ecb->dte_size,
10705 rec->dtrd_alignment);
10706 rec->dtrd_offset = ecb->dte_size;
10707 if (ecb->dte_size + rec->dtrd_size < ecb->dte_size)
10708 return (EINVAL);
10709 ecb->dte_size += rec->dtrd_size;
10710 ecb->dte_needed = MAX(ecb->dte_needed, ecb->dte_size);
10711 }
10712 }
10713
10714 if ((act = ecb->dte_action) != NULL &&
10715 !(act->dta_kind == DTRACEACT_SPECULATE && act->dta_next == NULL) &&
10716 ecb->dte_size == sizeof (dtrace_rechdr_t)) {
10717 /*
10718 * If the size is still sizeof (dtrace_rechdr_t), then all
10719 * actions store no data; set the size to 0.
10720 */
10721 ecb->dte_size = 0;
10722 }
10723
10724 ecb->dte_size = P2ROUNDUP(ecb->dte_size, sizeof (dtrace_epid_t));
10725 ecb->dte_needed = P2ROUNDUP(ecb->dte_needed, (sizeof (dtrace_epid_t)));
10726 ecb->dte_state->dts_needed = MAX(ecb->dte_state->dts_needed,
10727 ecb->dte_needed);
10728 return (0);
10729 }
10730
10731 static dtrace_action_t *
10732 dtrace_ecb_aggregation_create(dtrace_ecb_t *ecb, dtrace_actdesc_t *desc)
10733 {
10734 dtrace_aggregation_t *agg;
10735 size_t size = sizeof (uint64_t);
10736 int ntuple = desc->dtad_ntuple;
10737 dtrace_action_t *act;
10738 dtrace_recdesc_t *frec;
10739 dtrace_aggid_t aggid;
10740 dtrace_state_t *state = ecb->dte_state;
10741
10742 agg = kmem_zalloc(sizeof (dtrace_aggregation_t), KM_SLEEP);
10743 agg->dtag_ecb = ecb;
10744
10745 ASSERT(DTRACEACT_ISAGG(desc->dtad_kind));
10746
10747 switch (desc->dtad_kind) {
10748 case DTRACEAGG_MIN:
10749 agg->dtag_initial = INT64_MAX;
10750 agg->dtag_aggregate = dtrace_aggregate_min;
10751 break;
10752
10753 case DTRACEAGG_MAX:
10754 agg->dtag_initial = INT64_MIN;
10755 agg->dtag_aggregate = dtrace_aggregate_max;
10756 break;
10757
10758 case DTRACEAGG_COUNT:
10759 agg->dtag_aggregate = dtrace_aggregate_count;
10760 break;
10761
10762 case DTRACEAGG_QUANTIZE:
10763 agg->dtag_aggregate = dtrace_aggregate_quantize;
10764 size = (((sizeof (uint64_t) * NBBY) - 1) * 2 + 1) *
10765 sizeof (uint64_t);
10766 break;
10767
10768 case DTRACEAGG_LQUANTIZE: {
10769 uint16_t step = DTRACE_LQUANTIZE_STEP(desc->dtad_arg);
10770 uint16_t levels = DTRACE_LQUANTIZE_LEVELS(desc->dtad_arg);
10771
10772 agg->dtag_initial = desc->dtad_arg;
10773 agg->dtag_aggregate = dtrace_aggregate_lquantize;
10774
10775 if (step == 0 || levels == 0)
10776 goto err;
10777
10778 size = levels * sizeof (uint64_t) + 3 * sizeof (uint64_t);
10779 break;
10780 }
10781
10782 case DTRACEAGG_LLQUANTIZE: {
10783 uint16_t factor = DTRACE_LLQUANTIZE_FACTOR(desc->dtad_arg);
10784 uint16_t low = DTRACE_LLQUANTIZE_LOW(desc->dtad_arg);
10785 uint16_t high = DTRACE_LLQUANTIZE_HIGH(desc->dtad_arg);
10786 uint16_t nsteps = DTRACE_LLQUANTIZE_NSTEP(desc->dtad_arg);
10787 int64_t v;
10788
10789 agg->dtag_initial = desc->dtad_arg;
10790 agg->dtag_aggregate = dtrace_aggregate_llquantize;
10791
10792 if (factor < 2 || low >= high || nsteps < factor)
10793 goto err;
10794
10795 /*
10796 * Now check that the number of steps evenly divides a power
10797 * of the factor. (This assures both integer bucket size and
10798 * linearity within each magnitude.)
10799 */
10800 for (v = factor; v < nsteps; v *= factor)
10801 continue;
10802
10803 if ((v % nsteps) || (nsteps % factor))
10804 goto err;
10805
10806 size = (dtrace_aggregate_llquantize_bucket(factor,
10807 low, high, nsteps, INT64_MAX) + 2) * sizeof (uint64_t);
10808 break;
10809 }
10810
10811 case DTRACEAGG_AVG:
10812 agg->dtag_aggregate = dtrace_aggregate_avg;
10813 size = sizeof (uint64_t) * 2;
10814 break;
10815
10816 case DTRACEAGG_STDDEV:
10817 agg->dtag_aggregate = dtrace_aggregate_stddev;
10818 size = sizeof (uint64_t) * 4;
10819 break;
10820
10821 case DTRACEAGG_SUM:
10822 agg->dtag_aggregate = dtrace_aggregate_sum;
10823 break;
10824
10825 default:
10826 goto err;
10827 }
10828
10829 agg->dtag_action.dta_rec.dtrd_size = size;
10830
10831 if (ntuple == 0)
10832 goto err;
10833
10834 /*
10835 * We must make sure that we have enough actions for the n-tuple.
10836 */
10837 for (act = ecb->dte_action_last; act != NULL; act = act->dta_prev) {
10838 if (DTRACEACT_ISAGG(act->dta_kind))
10839 break;
10840
10841 if (--ntuple == 0) {
10842 /*
10843 * This is the action with which our n-tuple begins.
10844 */
10845 agg->dtag_first = act;
10846 goto success;
10847 }
10848 }
10849
10850 /*
10851 * This n-tuple is short by ntuple elements. Return failure.
10852 */
10853 ASSERT(ntuple != 0);
10854 err:
10855 kmem_free(agg, sizeof (dtrace_aggregation_t));
10856 return (NULL);
10857
10858 success:
10859 /*
10860 * If the last action in the tuple has a size of zero, it's actually
10861 * an expression argument for the aggregating action.
10862 */
10863 ASSERT(ecb->dte_action_last != NULL);
10864 act = ecb->dte_action_last;
10865
10866 if (act->dta_kind == DTRACEACT_DIFEXPR) {
10867 ASSERT(act->dta_difo != NULL);
10868
10869 if (act->dta_difo->dtdo_rtype.dtdt_size == 0)
10870 agg->dtag_hasarg = 1;
10871 }
10872
10873 /*
10874 * We need to allocate an id for this aggregation.
10875 */
10876 aggid = (dtrace_aggid_t)(uintptr_t)vmem_alloc(state->dts_aggid_arena, 1,
10877 VM_BESTFIT | VM_SLEEP);
10878
10879 if (aggid - 1 >= state->dts_naggregations) {
10880 dtrace_aggregation_t **oaggs = state->dts_aggregations;
10881 dtrace_aggregation_t **aggs;
10882 int naggs = state->dts_naggregations << 1;
10883 int onaggs = state->dts_naggregations;
10884
10885 ASSERT(aggid == state->dts_naggregations + 1);
10886
10887 if (naggs == 0) {
10888 ASSERT(oaggs == NULL);
10889 naggs = 1;
10890 }
10891
10892 aggs = kmem_zalloc(naggs * sizeof (*aggs), KM_SLEEP);
10893
10894 if (oaggs != NULL) {
10895 bcopy(oaggs, aggs, onaggs * sizeof (*aggs));
10896 kmem_free(oaggs, onaggs * sizeof (*aggs));
10897 }
10898
10899 state->dts_aggregations = aggs;
10900 state->dts_naggregations = naggs;
10901 }
10902
10903 ASSERT(state->dts_aggregations[aggid - 1] == NULL);
10904 state->dts_aggregations[(agg->dtag_id = aggid) - 1] = agg;
10905
10906 frec = &agg->dtag_first->dta_rec;
10907 if (frec->dtrd_alignment < sizeof (dtrace_aggid_t))
10908 frec->dtrd_alignment = sizeof (dtrace_aggid_t);
10909
10910 for (act = agg->dtag_first; act != NULL; act = act->dta_next) {
10911 ASSERT(!act->dta_intuple);
10912 act->dta_intuple = 1;
10913 }
10914
10915 return (&agg->dtag_action);
10916 }
10917
10918 static void
10919 dtrace_ecb_aggregation_destroy(dtrace_ecb_t *ecb, dtrace_action_t *act)
10920 {
10921 dtrace_aggregation_t *agg = (dtrace_aggregation_t *)act;
10922 dtrace_state_t *state = ecb->dte_state;
10923 dtrace_aggid_t aggid = agg->dtag_id;
10924
10925 ASSERT(DTRACEACT_ISAGG(act->dta_kind));
10926 vmem_free(state->dts_aggid_arena, (void *)(uintptr_t)aggid, 1);
10927
10928 ASSERT(state->dts_aggregations[aggid - 1] == agg);
10929 state->dts_aggregations[aggid - 1] = NULL;
10930
10931 kmem_free(agg, sizeof (dtrace_aggregation_t));
10932 }
10933
10934 static int
10935 dtrace_ecb_action_add(dtrace_ecb_t *ecb, dtrace_actdesc_t *desc)
10936 {
10937 dtrace_action_t *action, *last;
10938 dtrace_difo_t *dp = desc->dtad_difo;
10939 uint32_t size = 0, align = sizeof (uint8_t), mask;
10940 uint16_t format = 0;
10941 dtrace_recdesc_t *rec;
10942 dtrace_state_t *state = ecb->dte_state;
10943 dtrace_optval_t *opt = state->dts_options, nframes, strsize;
10944 uint64_t arg = desc->dtad_arg;
10945
10946 ASSERT(MUTEX_HELD(&dtrace_lock));
10947 ASSERT(ecb->dte_action == NULL || ecb->dte_action->dta_refcnt == 1);
10948
10949 if (DTRACEACT_ISAGG(desc->dtad_kind)) {
10950 /*
10951 * If this is an aggregating action, there must be neither
10952 * a speculate nor a commit on the action chain.
10953 */
10954 dtrace_action_t *act;
10955
10956 for (act = ecb->dte_action; act != NULL; act = act->dta_next) {
10957 if (act->dta_kind == DTRACEACT_COMMIT)
10958 return (EINVAL);
10959
10960 if (act->dta_kind == DTRACEACT_SPECULATE)
10961 return (EINVAL);
10962 }
10963
10964 action = dtrace_ecb_aggregation_create(ecb, desc);
10965
10966 if (action == NULL)
10967 return (EINVAL);
10968 } else {
10969 if (DTRACEACT_ISDESTRUCTIVE(desc->dtad_kind) ||
10970 (desc->dtad_kind == DTRACEACT_DIFEXPR &&
10971 dp != NULL && dp->dtdo_destructive)) {
10972 state->dts_destructive = 1;
10973 }
10974
10975 switch (desc->dtad_kind) {
10976 case DTRACEACT_PRINTF:
10977 case DTRACEACT_PRINTA:
10978 case DTRACEACT_SYSTEM:
10979 case DTRACEACT_FREOPEN:
10980 case DTRACEACT_DIFEXPR:
10981 /*
10982 * We know that our arg is a string -- turn it into a
10983 * format.
10984 */
10985 if (arg == NULL) {
10986 ASSERT(desc->dtad_kind == DTRACEACT_PRINTA ||
10987 desc->dtad_kind == DTRACEACT_DIFEXPR);
10988 format = 0;
10989 } else {
10990 ASSERT(arg != NULL);
10991 ASSERT(arg > KERNELBASE);
10992 format = dtrace_format_add(state,
10993 (char *)(uintptr_t)arg);
10994 }
10995
10996 /*FALLTHROUGH*/
10997 case DTRACEACT_LIBACT:
10998 case DTRACEACT_TRACEMEM:
10999 case DTRACEACT_TRACEMEM_DYNSIZE:
11000 if (dp == NULL)
11001 return (EINVAL);
11002
11003 if ((size = dp->dtdo_rtype.dtdt_size) != 0)
11004 break;
11005
11006 if (dp->dtdo_rtype.dtdt_kind == DIF_TYPE_STRING) {
11007 if (!(dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF))
11008 return (EINVAL);
11009
11010 size = opt[DTRACEOPT_STRSIZE];
11011 }
11012
11013 break;
11014
11015 case DTRACEACT_STACK:
11016 if ((nframes = arg) == 0) {
11017 nframes = opt[DTRACEOPT_STACKFRAMES];
11018 ASSERT(nframes > 0);
11019 arg = nframes;
11020 }
11021
11022 size = nframes * sizeof (pc_t);
11023 break;
11024
11025 case DTRACEACT_JSTACK:
11026 if ((strsize = DTRACE_USTACK_STRSIZE(arg)) == 0)
11027 strsize = opt[DTRACEOPT_JSTACKSTRSIZE];
11028
11029 if ((nframes = DTRACE_USTACK_NFRAMES(arg)) == 0)
11030 nframes = opt[DTRACEOPT_JSTACKFRAMES];
11031
11032 arg = DTRACE_USTACK_ARG(nframes, strsize);
11033
11034 /*FALLTHROUGH*/
11035 case DTRACEACT_USTACK:
11036 if (desc->dtad_kind != DTRACEACT_JSTACK &&
11037 (nframes = DTRACE_USTACK_NFRAMES(arg)) == 0) {
11038 strsize = DTRACE_USTACK_STRSIZE(arg);
11039 nframes = opt[DTRACEOPT_USTACKFRAMES];
11040 ASSERT(nframes > 0);
11041 arg = DTRACE_USTACK_ARG(nframes, strsize);
11042 }
11043
11044 /*
11045 * Save a slot for the pid.
11046 */
11047 size = (nframes + 1) * sizeof (uint64_t);
11048 size += DTRACE_USTACK_STRSIZE(arg);
11049 size = P2ROUNDUP(size, (uint32_t)(sizeof (uintptr_t)));
11050
11051 break;
11052
11053 case DTRACEACT_SYM:
11054 case DTRACEACT_MOD:
11055 if (dp == NULL || ((size = dp->dtdo_rtype.dtdt_size) !=
11056 sizeof (uint64_t)) ||
11057 (dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF))
11058 return (EINVAL);
11059 break;
11060
11061 case DTRACEACT_USYM:
11062 case DTRACEACT_UMOD:
11063 case DTRACEACT_UADDR:
11064 if (dp == NULL ||
11065 (dp->dtdo_rtype.dtdt_size != sizeof (uint64_t)) ||
11066 (dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF))
11067 return (EINVAL);
11068
11069 /*
11070 * We have a slot for the pid, plus a slot for the
11071 * argument. To keep things simple (aligned with
11072 * bitness-neutral sizing), we store each as a 64-bit
11073 * quantity.
11074 */
11075 size = 2 * sizeof (uint64_t);
11076 break;
11077
11078 case DTRACEACT_STOP:
11079 case DTRACEACT_BREAKPOINT:
11080 case DTRACEACT_PANIC:
11081 break;
11082
11083 case DTRACEACT_CHILL:
11084 case DTRACEACT_DISCARD:
11085 case DTRACEACT_RAISE:
11086 if (dp == NULL)
11087 return (EINVAL);
11088 break;
11089
11090 case DTRACEACT_EXIT:
11091 if (dp == NULL ||
11092 (size = dp->dtdo_rtype.dtdt_size) != sizeof (int) ||
11093 (dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF))
11094 return (EINVAL);
11095 break;
11096
11097 case DTRACEACT_SPECULATE:
11098 if (ecb->dte_size > sizeof (dtrace_rechdr_t))
11099 return (EINVAL);
11100
11101 if (dp == NULL)
11102 return (EINVAL);
11103
11104 state->dts_speculates = 1;
11105 break;
11106
11107 case DTRACEACT_COMMIT: {
11108 dtrace_action_t *act = ecb->dte_action;
11109
11110 for (; act != NULL; act = act->dta_next) {
11111 if (act->dta_kind == DTRACEACT_COMMIT)
11112 return (EINVAL);
11113 }
11114
11115 if (dp == NULL)
11116 return (EINVAL);
11117 break;
11118 }
11119
11120 default:
11121 return (EINVAL);
11122 }
11123
11124 if (size != 0 || desc->dtad_kind == DTRACEACT_SPECULATE) {
11125 /*
11126 * If this is a data-storing action or a speculate,
11127 * we must be sure that there isn't a commit on the
11128 * action chain.
11129 */
11130 dtrace_action_t *act = ecb->dte_action;
11131
11132 for (; act != NULL; act = act->dta_next) {
11133 if (act->dta_kind == DTRACEACT_COMMIT)
11134 return (EINVAL);
11135 }
11136 }
11137
11138 action = kmem_zalloc(sizeof (dtrace_action_t), KM_SLEEP);
11139 action->dta_rec.dtrd_size = size;
11140 }
11141
11142 action->dta_refcnt = 1;
11143 rec = &action->dta_rec;
11144 size = rec->dtrd_size;
11145
11146 for (mask = sizeof (uint64_t) - 1; size != 0 && mask > 0; mask >>= 1) {
11147 if (!(size & mask)) {
11148 align = mask + 1;
11149 break;
11150 }
11151 }
11152
11153 action->dta_kind = desc->dtad_kind;
11154
11155 if ((action->dta_difo = dp) != NULL)
11156 dtrace_difo_hold(dp);
11157
11158 rec->dtrd_action = action->dta_kind;
11159 rec->dtrd_arg = arg;
11160 rec->dtrd_uarg = desc->dtad_uarg;
11161 rec->dtrd_alignment = (uint16_t)align;
11162 rec->dtrd_format = format;
11163
11164 if ((last = ecb->dte_action_last) != NULL) {
11165 ASSERT(ecb->dte_action != NULL);
11166 action->dta_prev = last;
11167 last->dta_next = action;
11168 } else {
11169 ASSERT(ecb->dte_action == NULL);
11170 ecb->dte_action = action;
11171 }
11172
11173 ecb->dte_action_last = action;
11174
11175 return (0);
11176 }
11177
11178 static void
11179 dtrace_ecb_action_remove(dtrace_ecb_t *ecb)
11180 {
11181 dtrace_action_t *act = ecb->dte_action, *next;
11182 dtrace_vstate_t *vstate = &ecb->dte_state->dts_vstate;
11183 dtrace_difo_t *dp;
11184 uint16_t format;
11185
11186 if (act != NULL && act->dta_refcnt > 1) {
11187 ASSERT(act->dta_next == NULL || act->dta_next->dta_refcnt == 1);
11188 act->dta_refcnt--;
11189 } else {
11190 for (; act != NULL; act = next) {
11191 next = act->dta_next;
11192 ASSERT(next != NULL || act == ecb->dte_action_last);
11193 ASSERT(act->dta_refcnt == 1);
11194
11195 if ((format = act->dta_rec.dtrd_format) != 0)
11196 dtrace_format_remove(ecb->dte_state, format);
11197
11198 if ((dp = act->dta_difo) != NULL)
11199 dtrace_difo_release(dp, vstate);
11200
11201 if (DTRACEACT_ISAGG(act->dta_kind)) {
11202 dtrace_ecb_aggregation_destroy(ecb, act);
11203 } else {
11204 kmem_free(act, sizeof (dtrace_action_t));
11205 }
11206 }
11207 }
11208
11209 ecb->dte_action = NULL;
11210 ecb->dte_action_last = NULL;
11211 ecb->dte_size = 0;
11212 }
11213
11214 static void
11215 dtrace_ecb_disable(dtrace_ecb_t *ecb)
11216 {
11217 /*
11218 * We disable the ECB by removing it from its probe.
11219 */
11220 dtrace_ecb_t *pecb, *prev = NULL;
11221 dtrace_probe_t *probe = ecb->dte_probe;
11222
11223 ASSERT(MUTEX_HELD(&dtrace_lock));
11224
11225 if (probe == NULL) {
11226 /*
11227 * This is the NULL probe; there is nothing to disable.
11228 */
11229 return;
11230 }
11231
11232 for (pecb = probe->dtpr_ecb; pecb != NULL; pecb = pecb->dte_next) {
11233 if (pecb == ecb)
11234 break;
11235 prev = pecb;
11236 }
11237
11238 ASSERT(pecb != NULL);
11239
11240 if (prev == NULL) {
11241 probe->dtpr_ecb = ecb->dte_next;
11242 } else {
11243 prev->dte_next = ecb->dte_next;
11244 }
11245
11246 if (ecb == probe->dtpr_ecb_last) {
11247 ASSERT(ecb->dte_next == NULL);
11248 probe->dtpr_ecb_last = prev;
11249 }
11250
11251 /*
11252 * The ECB has been disconnected from the probe; now sync to assure
11253 * that all CPUs have seen the change before returning.
11254 */
11255 dtrace_sync();
11256
11257 if (probe->dtpr_ecb == NULL) {
11258 /*
11259 * That was the last ECB on the probe; clear the predicate
11260 * cache ID for the probe, disable it and sync one more time
11261 * to assure that we'll never hit it again.
11262 */
11263 dtrace_provider_t *prov = probe->dtpr_provider;
11264
11265 ASSERT(ecb->dte_next == NULL);
11266 ASSERT(probe->dtpr_ecb_last == NULL);
11267 probe->dtpr_predcache = DTRACE_CACHEIDNONE;
11268 prov->dtpv_pops.dtps_disable(prov->dtpv_arg,
11269 probe->dtpr_id, probe->dtpr_arg);
11270 dtrace_sync();
11271 } else {
11272 /*
11273 * There is at least one ECB remaining on the probe. If there
11274 * is _exactly_ one, set the probe's predicate cache ID to be
11275 * the predicate cache ID of the remaining ECB.
11276 */
11277 ASSERT(probe->dtpr_ecb_last != NULL);
11278 ASSERT(probe->dtpr_predcache == DTRACE_CACHEIDNONE);
11279
11280 if (probe->dtpr_ecb == probe->dtpr_ecb_last) {
11281 dtrace_predicate_t *p = probe->dtpr_ecb->dte_predicate;
11282
11283 ASSERT(probe->dtpr_ecb->dte_next == NULL);
11284
11285 if (p != NULL)
11286 probe->dtpr_predcache = p->dtp_cacheid;
11287 }
11288
11289 ecb->dte_next = NULL;
11290 }
11291 }
11292
11293 static void
11294 dtrace_ecb_destroy(dtrace_ecb_t *ecb)
11295 {
11296 dtrace_state_t *state = ecb->dte_state;
11297 dtrace_vstate_t *vstate = &state->dts_vstate;
11298 dtrace_predicate_t *pred;
11299 dtrace_epid_t epid = ecb->dte_epid;
11300
11301 ASSERT(MUTEX_HELD(&dtrace_lock));
11302 ASSERT(ecb->dte_next == NULL);
11303 ASSERT(ecb->dte_probe == NULL || ecb->dte_probe->dtpr_ecb != ecb);
11304
11305 if ((pred = ecb->dte_predicate) != NULL)
11306 dtrace_predicate_release(pred, vstate);
11307
11308 dtrace_ecb_action_remove(ecb);
11309
11310 ASSERT(state->dts_ecbs[epid - 1] == ecb);
11311 state->dts_ecbs[epid - 1] = NULL;
11312
11313 kmem_free(ecb, sizeof (dtrace_ecb_t));
11314 }
11315
11316 static dtrace_ecb_t *
11317 dtrace_ecb_create(dtrace_state_t *state, dtrace_probe_t *probe,
11318 dtrace_enabling_t *enab)
11319 {
11320 dtrace_ecb_t *ecb;
11321 dtrace_predicate_t *pred;
11322 dtrace_actdesc_t *act;
11323 dtrace_provider_t *prov;
11324 dtrace_ecbdesc_t *desc = enab->dten_current;
11325
11326 ASSERT(MUTEX_HELD(&dtrace_lock));
11327 ASSERT(state != NULL);
11328
11329 ecb = dtrace_ecb_add(state, probe);
11330 ecb->dte_uarg = desc->dted_uarg;
11331
11332 if ((pred = desc->dted_pred.dtpdd_predicate) != NULL) {
11333 dtrace_predicate_hold(pred);
11334 ecb->dte_predicate = pred;
11335 }
11336
11337 if (probe != NULL) {
11338 /*
11339 * If the provider shows more leg than the consumer is old
11340 * enough to see, we need to enable the appropriate implicit
11341 * predicate bits to prevent the ecb from activating at
11342 * revealing times.
11343 *
11344 * Providers specifying DTRACE_PRIV_USER at register time
11345 * are stating that they need the /proc-style privilege
11346 * model to be enforced, and this is what DTRACE_COND_OWNER
11347 * and DTRACE_COND_ZONEOWNER will then do at probe time.
11348 */
11349 prov = probe->dtpr_provider;
11350 if (!(state->dts_cred.dcr_visible & DTRACE_CRV_ALLPROC) &&
11351 (prov->dtpv_priv.dtpp_flags & DTRACE_PRIV_USER))
11352 ecb->dte_cond |= DTRACE_COND_OWNER;
11353
11354 if (!(state->dts_cred.dcr_visible & DTRACE_CRV_ALLZONE) &&
11355 (prov->dtpv_priv.dtpp_flags & DTRACE_PRIV_USER))
11356 ecb->dte_cond |= DTRACE_COND_ZONEOWNER;
11357
11358 /*
11359 * If the provider shows us kernel innards and the user
11360 * is lacking sufficient privilege, enable the
11361 * DTRACE_COND_USERMODE implicit predicate.
11362 */
11363 if (!(state->dts_cred.dcr_visible & DTRACE_CRV_KERNEL) &&
11364 (prov->dtpv_priv.dtpp_flags & DTRACE_PRIV_KERNEL))
11365 ecb->dte_cond |= DTRACE_COND_USERMODE;
11366 }
11367
11368 if (dtrace_ecb_create_cache != NULL) {
11369 /*
11370 * If we have a cached ecb, we'll use its action list instead
11371 * of creating our own (saving both time and space).
11372 */
11373 dtrace_ecb_t *cached = dtrace_ecb_create_cache;
11374 dtrace_action_t *act = cached->dte_action;
11375
11376 if (act != NULL) {
11377 ASSERT(act->dta_refcnt > 0);
11378 act->dta_refcnt++;
11379 ecb->dte_action = act;
11380 ecb->dte_action_last = cached->dte_action_last;
11381 ecb->dte_needed = cached->dte_needed;
11382 ecb->dte_size = cached->dte_size;
11383 ecb->dte_alignment = cached->dte_alignment;
11384 }
11385
11386 return (ecb);
11387 }
11388
11389 for (act = desc->dted_action; act != NULL; act = act->dtad_next) {
11390 if ((enab->dten_error = dtrace_ecb_action_add(ecb, act)) != 0) {
11391 dtrace_ecb_destroy(ecb);
11392 return (NULL);
11393 }
11394 }
11395
11396 if ((enab->dten_error = dtrace_ecb_resize(ecb)) != 0) {
11397 dtrace_ecb_destroy(ecb);
11398 return (NULL);
11399 }
11400
11401 return (dtrace_ecb_create_cache = ecb);
11402 }
11403
11404 static int
11405 dtrace_ecb_create_enable(dtrace_probe_t *probe, void *arg)
11406 {
11407 dtrace_ecb_t *ecb;
11408 dtrace_enabling_t *enab = arg;
11409 dtrace_state_t *state = enab->dten_vstate->dtvs_state;
11410
11411 ASSERT(state != NULL);
11412
11413 if (probe != NULL && probe->dtpr_gen < enab->dten_probegen) {
11414 /*
11415 * This probe was created in a generation for which this
11416 * enabling has previously created ECBs; we don't want to
11417 * enable it again, so just kick out.
11418 */
11419 return (DTRACE_MATCH_NEXT);
11420 }
11421
11422 if ((ecb = dtrace_ecb_create(state, probe, enab)) == NULL)
11423 return (DTRACE_MATCH_DONE);
11424
11425 if (dtrace_ecb_enable(ecb) < 0)
11426 return (DTRACE_MATCH_FAIL);
11427
11428 return (DTRACE_MATCH_NEXT);
11429 }
11430
11431 static dtrace_ecb_t *
11432 dtrace_epid2ecb(dtrace_state_t *state, dtrace_epid_t id)
11433 {
11434 dtrace_ecb_t *ecb;
11435
11436 ASSERT(MUTEX_HELD(&dtrace_lock));
11437
11438 if (id == 0 || id > state->dts_necbs)
11439 return (NULL);
11440
11441 ASSERT(state->dts_necbs > 0 && state->dts_ecbs != NULL);
11442 ASSERT((ecb = state->dts_ecbs[id - 1]) == NULL || ecb->dte_epid == id);
11443
11444 return (state->dts_ecbs[id - 1]);
11445 }
11446
11447 static dtrace_aggregation_t *
11448 dtrace_aggid2agg(dtrace_state_t *state, dtrace_aggid_t id)
11449 {
11450 dtrace_aggregation_t *agg;
11451
11452 ASSERT(MUTEX_HELD(&dtrace_lock));
11453
11454 if (id == 0 || id > state->dts_naggregations)
11455 return (NULL);
11456
11457 ASSERT(state->dts_naggregations > 0 && state->dts_aggregations != NULL);
11458 ASSERT((agg = state->dts_aggregations[id - 1]) == NULL ||
11459 agg->dtag_id == id);
11460
11461 return (state->dts_aggregations[id - 1]);
11462 }
11463
11464 /*
11465 * DTrace Buffer Functions
11466 *
11467 * The following functions manipulate DTrace buffers. Most of these functions
11468 * are called in the context of establishing or processing consumer state;
11469 * exceptions are explicitly noted.
11470 */
11471
11472 /*
11473 * Note: called from cross call context. This function switches the two
11474 * buffers on a given CPU. The atomicity of this operation is assured by
11475 * disabling interrupts while the actual switch takes place; the disabling of
11476 * interrupts serializes the execution with any execution of dtrace_probe() on
11477 * the same CPU.
11478 */
11479 static void
11480 dtrace_buffer_switch(dtrace_buffer_t *buf)
11481 {
11482 caddr_t tomax = buf->dtb_tomax;
11483 caddr_t xamot = buf->dtb_xamot;
11484 dtrace_icookie_t cookie;
11485 hrtime_t now;
11486
11487 ASSERT(!(buf->dtb_flags & DTRACEBUF_NOSWITCH));
11488 ASSERT(!(buf->dtb_flags & DTRACEBUF_RING));
11489
11490 cookie = dtrace_interrupt_disable();
11491 now = dtrace_gethrtime();
11492 buf->dtb_tomax = xamot;
11493 buf->dtb_xamot = tomax;
11494 buf->dtb_xamot_drops = buf->dtb_drops;
11495 buf->dtb_xamot_offset = buf->dtb_offset;
11496 buf->dtb_xamot_errors = buf->dtb_errors;
11497 buf->dtb_xamot_flags = buf->dtb_flags;
11498 buf->dtb_offset = 0;
11499 buf->dtb_drops = 0;
11500 buf->dtb_errors = 0;
11501 buf->dtb_flags &= ~(DTRACEBUF_ERROR | DTRACEBUF_DROPPED);
11502 buf->dtb_interval = now - buf->dtb_switched;
11503 buf->dtb_switched = now;
11504 dtrace_interrupt_enable(cookie);
11505 }
11506
11507 /*
11508 * Note: called from cross call context. This function activates a buffer
11509 * on a CPU. As with dtrace_buffer_switch(), the atomicity of the operation
11510 * is guaranteed by the disabling of interrupts.
11511 */
11512 static void
11513 dtrace_buffer_activate(dtrace_state_t *state)
11514 {
11515 dtrace_buffer_t *buf;
11516 dtrace_icookie_t cookie = dtrace_interrupt_disable();
11517
11518 buf = &state->dts_buffer[CPU->cpu_id];
11519
11520 if (buf->dtb_tomax != NULL) {
11521 /*
11522 * We might like to assert that the buffer is marked inactive,
11523 * but this isn't necessarily true: the buffer for the CPU
11524 * that processes the BEGIN probe has its buffer activated
11525 * manually. In this case, we take the (harmless) action
11526 * re-clearing the bit INACTIVE bit.
11527 */
11528 buf->dtb_flags &= ~DTRACEBUF_INACTIVE;
11529 }
11530
11531 dtrace_interrupt_enable(cookie);
11532 }
11533
11534 static int
11535 dtrace_buffer_alloc(dtrace_buffer_t *bufs, size_t size, int flags,
11536 processorid_t cpu, int *factor)
11537 {
11538 cpu_t *cp;
11539 dtrace_buffer_t *buf;
11540 int allocated = 0, desired = 0;
11541
11542 ASSERT(MUTEX_HELD(&cpu_lock));
11543 ASSERT(MUTEX_HELD(&dtrace_lock));
11544
11545 *factor = 1;
11546
11547 if (size > dtrace_nonroot_maxsize &&
11548 !PRIV_POLICY_CHOICE(CRED(), PRIV_ALL, B_FALSE))
11549 return (EFBIG);
11550
11551 cp = cpu_list;
11552
11553 do {
11554 if (cpu != DTRACE_CPUALL && cpu != cp->cpu_id)
11555 continue;
11556
11557 buf = &bufs[cp->cpu_id];
11558
11559 /*
11560 * If there is already a buffer allocated for this CPU, it
11561 * is only possible that this is a DR event. In this case,
11562 * the buffer size must match our specified size.
11563 */
11564 if (buf->dtb_tomax != NULL) {
11565 ASSERT(buf->dtb_size == size);
11566 continue;
11567 }
11568
11569 ASSERT(buf->dtb_xamot == NULL);
11570
11571 if ((buf->dtb_tomax = kmem_zalloc(size,
11572 KM_NOSLEEP | KM_NORMALPRI)) == NULL)
11573 goto err;
11574
11575 buf->dtb_size = size;
11576 buf->dtb_flags = flags;
11577 buf->dtb_offset = 0;
11578 buf->dtb_drops = 0;
11579
11580 if (flags & DTRACEBUF_NOSWITCH)
11581 continue;
11582
11583 if ((buf->dtb_xamot = kmem_zalloc(size,
11584 KM_NOSLEEP | KM_NORMALPRI)) == NULL)
11585 goto err;
11586 } while ((cp = cp->cpu_next) != cpu_list);
11587
11588 return (0);
11589
11590 err:
11591 cp = cpu_list;
11592
11593 do {
11594 if (cpu != DTRACE_CPUALL && cpu != cp->cpu_id)
11595 continue;
11596
11597 buf = &bufs[cp->cpu_id];
11598 desired += 2;
11599
11600 if (buf->dtb_xamot != NULL) {
11601 ASSERT(buf->dtb_tomax != NULL);
11602 ASSERT(buf->dtb_size == size);
11603 kmem_free(buf->dtb_xamot, size);
11604 allocated++;
11605 }
11606
11607 if (buf->dtb_tomax != NULL) {
11608 ASSERT(buf->dtb_size == size);
11609 kmem_free(buf->dtb_tomax, size);
11610 allocated++;
11611 }
11612
11613 buf->dtb_tomax = NULL;
11614 buf->dtb_xamot = NULL;
11615 buf->dtb_size = 0;
11616 } while ((cp = cp->cpu_next) != cpu_list);
11617
11618 *factor = desired / (allocated > 0 ? allocated : 1);
11619
11620 return (ENOMEM);
11621 }
11622
11623 /*
11624 * Note: called from probe context. This function just increments the drop
11625 * count on a buffer. It has been made a function to allow for the
11626 * possibility of understanding the source of mysterious drop counts. (A
11627 * problem for which one may be particularly disappointed that DTrace cannot
11628 * be used to understand DTrace.)
11629 */
11630 static void
11631 dtrace_buffer_drop(dtrace_buffer_t *buf)
11632 {
11633 buf->dtb_drops++;
11634 }
11635
11636 /*
11637 * Note: called from probe context. This function is called to reserve space
11638 * in a buffer. If mstate is non-NULL, sets the scratch base and size in the
11639 * mstate. Returns the new offset in the buffer, or a negative value if an
11640 * error has occurred.
11641 */
11642 static intptr_t
11643 dtrace_buffer_reserve(dtrace_buffer_t *buf, size_t needed, size_t align,
11644 dtrace_state_t *state, dtrace_mstate_t *mstate)
11645 {
11646 intptr_t offs = buf->dtb_offset, soffs;
11647 intptr_t woffs;
11648 caddr_t tomax;
11649 size_t total;
11650
11651 if (buf->dtb_flags & DTRACEBUF_INACTIVE)
11652 return (-1);
11653
11654 if ((tomax = buf->dtb_tomax) == NULL) {
11655 dtrace_buffer_drop(buf);
11656 return (-1);
11657 }
11658
11659 if (!(buf->dtb_flags & (DTRACEBUF_RING | DTRACEBUF_FILL))) {
11660 while (offs & (align - 1)) {
11661 /*
11662 * Assert that our alignment is off by a number which
11663 * is itself sizeof (uint32_t) aligned.
11664 */
11665 ASSERT(!((align - (offs & (align - 1))) &
11666 (sizeof (uint32_t) - 1)));
11667 DTRACE_STORE(uint32_t, tomax, offs, DTRACE_EPIDNONE);
11668 offs += sizeof (uint32_t);
11669 }
11670
11671 if ((soffs = offs + needed) > buf->dtb_size) {
11672 dtrace_buffer_drop(buf);
11673 return (-1);
11674 }
11675
11676 if (mstate == NULL)
11677 return (offs);
11678
11679 mstate->dtms_scratch_base = (uintptr_t)tomax + soffs;
11680 mstate->dtms_scratch_size = buf->dtb_size - soffs;
11681 mstate->dtms_scratch_ptr = mstate->dtms_scratch_base;
11682
11683 return (offs);
11684 }
11685
11686 if (buf->dtb_flags & DTRACEBUF_FILL) {
11687 if (state->dts_activity != DTRACE_ACTIVITY_COOLDOWN &&
11688 (buf->dtb_flags & DTRACEBUF_FULL))
11689 return (-1);
11690 goto out;
11691 }
11692
11693 total = needed + (offs & (align - 1));
11694
11695 /*
11696 * For a ring buffer, life is quite a bit more complicated. Before
11697 * we can store any padding, we need to adjust our wrapping offset.
11698 * (If we've never before wrapped or we're not about to, no adjustment
11699 * is required.)
11700 */
11701 if ((buf->dtb_flags & DTRACEBUF_WRAPPED) ||
11702 offs + total > buf->dtb_size) {
11703 woffs = buf->dtb_xamot_offset;
11704
11705 if (offs + total > buf->dtb_size) {
11706 /*
11707 * We can't fit in the end of the buffer. First, a
11708 * sanity check that we can fit in the buffer at all.
11709 */
11710 if (total > buf->dtb_size) {
11711 dtrace_buffer_drop(buf);
11712 return (-1);
11713 }
11714
11715 /*
11716 * We're going to be storing at the top of the buffer,
11717 * so now we need to deal with the wrapped offset. We
11718 * only reset our wrapped offset to 0 if it is
11719 * currently greater than the current offset. If it
11720 * is less than the current offset, it is because a
11721 * previous allocation induced a wrap -- but the
11722 * allocation didn't subsequently take the space due
11723 * to an error or false predicate evaluation. In this
11724 * case, we'll just leave the wrapped offset alone: if
11725 * the wrapped offset hasn't been advanced far enough
11726 * for this allocation, it will be adjusted in the
11727 * lower loop.
11728 */
11729 if (buf->dtb_flags & DTRACEBUF_WRAPPED) {
11730 if (woffs >= offs)
11731 woffs = 0;
11732 } else {
11733 woffs = 0;
11734 }
11735
11736 /*
11737 * Now we know that we're going to be storing to the
11738 * top of the buffer and that there is room for us
11739 * there. We need to clear the buffer from the current
11740 * offset to the end (there may be old gunk there).
11741 */
11742 while (offs < buf->dtb_size)
11743 tomax[offs++] = 0;
11744
11745 /*
11746 * We need to set our offset to zero. And because we
11747 * are wrapping, we need to set the bit indicating as
11748 * much. We can also adjust our needed space back
11749 * down to the space required by the ECB -- we know
11750 * that the top of the buffer is aligned.
11751 */
11752 offs = 0;
11753 total = needed;
11754 buf->dtb_flags |= DTRACEBUF_WRAPPED;
11755 } else {
11756 /*
11757 * There is room for us in the buffer, so we simply
11758 * need to check the wrapped offset.
11759 */
11760 if (woffs < offs) {
11761 /*
11762 * The wrapped offset is less than the offset.
11763 * This can happen if we allocated buffer space
11764 * that induced a wrap, but then we didn't
11765 * subsequently take the space due to an error
11766 * or false predicate evaluation. This is
11767 * okay; we know that _this_ allocation isn't
11768 * going to induce a wrap. We still can't
11769 * reset the wrapped offset to be zero,
11770 * however: the space may have been trashed in
11771 * the previous failed probe attempt. But at
11772 * least the wrapped offset doesn't need to
11773 * be adjusted at all...
11774 */
11775 goto out;
11776 }
11777 }
11778
11779 while (offs + total > woffs) {
11780 dtrace_epid_t epid = *(uint32_t *)(tomax + woffs);
11781 size_t size;
11782
11783 if (epid == DTRACE_EPIDNONE) {
11784 size = sizeof (uint32_t);
11785 } else {
11786 ASSERT3U(epid, <=, state->dts_necbs);
11787 ASSERT(state->dts_ecbs[epid - 1] != NULL);
11788
11789 size = state->dts_ecbs[epid - 1]->dte_size;
11790 }
11791
11792 ASSERT(woffs + size <= buf->dtb_size);
11793 ASSERT(size != 0);
11794
11795 if (woffs + size == buf->dtb_size) {
11796 /*
11797 * We've reached the end of the buffer; we want
11798 * to set the wrapped offset to 0 and break
11799 * out. However, if the offs is 0, then we're
11800 * in a strange edge-condition: the amount of
11801 * space that we want to reserve plus the size
11802 * of the record that we're overwriting is
11803 * greater than the size of the buffer. This
11804 * is problematic because if we reserve the
11805 * space but subsequently don't consume it (due
11806 * to a failed predicate or error) the wrapped
11807 * offset will be 0 -- yet the EPID at offset 0
11808 * will not be committed. This situation is
11809 * relatively easy to deal with: if we're in
11810 * this case, the buffer is indistinguishable
11811 * from one that hasn't wrapped; we need only
11812 * finish the job by clearing the wrapped bit,
11813 * explicitly setting the offset to be 0, and
11814 * zero'ing out the old data in the buffer.
11815 */
11816 if (offs == 0) {
11817 buf->dtb_flags &= ~DTRACEBUF_WRAPPED;
11818 buf->dtb_offset = 0;
11819 woffs = total;
11820
11821 while (woffs < buf->dtb_size)
11822 tomax[woffs++] = 0;
11823 }
11824
11825 woffs = 0;
11826 break;
11827 }
11828
11829 woffs += size;
11830 }
11831
11832 /*
11833 * We have a wrapped offset. It may be that the wrapped offset
11834 * has become zero -- that's okay.
11835 */
11836 buf->dtb_xamot_offset = woffs;
11837 }
11838
11839 out:
11840 /*
11841 * Now we can plow the buffer with any necessary padding.
11842 */
11843 while (offs & (align - 1)) {
11844 /*
11845 * Assert that our alignment is off by a number which
11846 * is itself sizeof (uint32_t) aligned.
11847 */
11848 ASSERT(!((align - (offs & (align - 1))) &
11849 (sizeof (uint32_t) - 1)));
11850 DTRACE_STORE(uint32_t, tomax, offs, DTRACE_EPIDNONE);
11851 offs += sizeof (uint32_t);
11852 }
11853
11854 if (buf->dtb_flags & DTRACEBUF_FILL) {
11855 if (offs + needed > buf->dtb_size - state->dts_reserve) {
11856 buf->dtb_flags |= DTRACEBUF_FULL;
11857 return (-1);
11858 }
11859 }
11860
11861 if (mstate == NULL)
11862 return (offs);
11863
11864 /*
11865 * For ring buffers and fill buffers, the scratch space is always
11866 * the inactive buffer.
11867 */
11868 mstate->dtms_scratch_base = (uintptr_t)buf->dtb_xamot;
11869 mstate->dtms_scratch_size = buf->dtb_size;
11870 mstate->dtms_scratch_ptr = mstate->dtms_scratch_base;
11871
11872 return (offs);
11873 }
11874
11875 static void
11876 dtrace_buffer_polish(dtrace_buffer_t *buf)
11877 {
11878 ASSERT(buf->dtb_flags & DTRACEBUF_RING);
11879 ASSERT(MUTEX_HELD(&dtrace_lock));
11880
11881 if (!(buf->dtb_flags & DTRACEBUF_WRAPPED))
11882 return;
11883
11884 /*
11885 * We need to polish the ring buffer. There are three cases:
11886 *
11887 * - The first (and presumably most common) is that there is no gap
11888 * between the buffer offset and the wrapped offset. In this case,
11889 * there is nothing in the buffer that isn't valid data; we can
11890 * mark the buffer as polished and return.
11891 *
11892 * - The second (less common than the first but still more common
11893 * than the third) is that there is a gap between the buffer offset
11894 * and the wrapped offset, and the wrapped offset is larger than the
11895 * buffer offset. This can happen because of an alignment issue, or
11896 * can happen because of a call to dtrace_buffer_reserve() that
11897 * didn't subsequently consume the buffer space. In this case,
11898 * we need to zero the data from the buffer offset to the wrapped
11899 * offset.
11900 *
11901 * - The third (and least common) is that there is a gap between the
11902 * buffer offset and the wrapped offset, but the wrapped offset is
11903 * _less_ than the buffer offset. This can only happen because a
11904 * call to dtrace_buffer_reserve() induced a wrap, but the space
11905 * was not subsequently consumed. In this case, we need to zero the
11906 * space from the offset to the end of the buffer _and_ from the
11907 * top of the buffer to the wrapped offset.
11908 */
11909 if (buf->dtb_offset < buf->dtb_xamot_offset) {
11910 bzero(buf->dtb_tomax + buf->dtb_offset,
11911 buf->dtb_xamot_offset - buf->dtb_offset);
11912 }
11913
11914 if (buf->dtb_offset > buf->dtb_xamot_offset) {
11915 bzero(buf->dtb_tomax + buf->dtb_offset,
11916 buf->dtb_size - buf->dtb_offset);
11917 bzero(buf->dtb_tomax, buf->dtb_xamot_offset);
11918 }
11919 }
11920
11921 /*
11922 * This routine determines if data generated at the specified time has likely
11923 * been entirely consumed at user-level. This routine is called to determine
11924 * if an ECB on a defunct probe (but for an active enabling) can be safely
11925 * disabled and destroyed.
11926 */
11927 static int
11928 dtrace_buffer_consumed(dtrace_buffer_t *bufs, hrtime_t when)
11929 {
11930 int i;
11931
11932 for (i = 0; i < NCPU; i++) {
11933 dtrace_buffer_t *buf = &bufs[i];
11934
11935 if (buf->dtb_size == 0)
11936 continue;
11937
11938 if (buf->dtb_flags & DTRACEBUF_RING)
11939 return (0);
11940
11941 if (!buf->dtb_switched && buf->dtb_offset != 0)
11942 return (0);
11943
11944 if (buf->dtb_switched - buf->dtb_interval < when)
11945 return (0);
11946 }
11947
11948 return (1);
11949 }
11950
11951 static void
11952 dtrace_buffer_free(dtrace_buffer_t *bufs)
11953 {
11954 int i;
11955
11956 for (i = 0; i < NCPU; i++) {
11957 dtrace_buffer_t *buf = &bufs[i];
11958
11959 if (buf->dtb_tomax == NULL) {
11960 ASSERT(buf->dtb_xamot == NULL);
11961 ASSERT(buf->dtb_size == 0);
11962 continue;
11963 }
11964
11965 if (buf->dtb_xamot != NULL) {
11966 ASSERT(!(buf->dtb_flags & DTRACEBUF_NOSWITCH));
11967 kmem_free(buf->dtb_xamot, buf->dtb_size);
11968 }
11969
11970 kmem_free(buf->dtb_tomax, buf->dtb_size);
11971 buf->dtb_size = 0;
11972 buf->dtb_tomax = NULL;
11973 buf->dtb_xamot = NULL;
11974 }
11975 }
11976
11977 /*
11978 * DTrace Enabling Functions
11979 */
11980 static dtrace_enabling_t *
11981 dtrace_enabling_create(dtrace_vstate_t *vstate)
11982 {
11983 dtrace_enabling_t *enab;
11984
11985 enab = kmem_zalloc(sizeof (dtrace_enabling_t), KM_SLEEP);
11986 enab->dten_vstate = vstate;
11987
11988 return (enab);
11989 }
11990
11991 static void
11992 dtrace_enabling_add(dtrace_enabling_t *enab, dtrace_ecbdesc_t *ecb)
11993 {
11994 dtrace_ecbdesc_t **ndesc;
11995 size_t osize, nsize;
11996
11997 /*
11998 * We can't add to enablings after we've enabled them, or after we've
11999 * retained them.
12000 */
12001 ASSERT(enab->dten_probegen == 0);
12002 ASSERT(enab->dten_next == NULL && enab->dten_prev == NULL);
12003
12004 if (enab->dten_ndesc < enab->dten_maxdesc) {
12005 enab->dten_desc[enab->dten_ndesc++] = ecb;
12006 return;
12007 }
12008
12009 osize = enab->dten_maxdesc * sizeof (dtrace_enabling_t *);
12010
12011 if (enab->dten_maxdesc == 0) {
12012 enab->dten_maxdesc = 1;
12013 } else {
12014 enab->dten_maxdesc <<= 1;
12015 }
12016
12017 ASSERT(enab->dten_ndesc < enab->dten_maxdesc);
12018
12019 nsize = enab->dten_maxdesc * sizeof (dtrace_enabling_t *);
12020 ndesc = kmem_zalloc(nsize, KM_SLEEP);
12021 bcopy(enab->dten_desc, ndesc, osize);
12022 kmem_free(enab->dten_desc, osize);
12023
12024 enab->dten_desc = ndesc;
12025 enab->dten_desc[enab->dten_ndesc++] = ecb;
12026 }
12027
12028 static void
12029 dtrace_enabling_addlike(dtrace_enabling_t *enab, dtrace_ecbdesc_t *ecb,
12030 dtrace_probedesc_t *pd)
12031 {
12032 dtrace_ecbdesc_t *new;
12033 dtrace_predicate_t *pred;
12034 dtrace_actdesc_t *act;
12035
12036 /*
12037 * We're going to create a new ECB description that matches the
12038 * specified ECB in every way, but has the specified probe description.
12039 */
12040 new = kmem_zalloc(sizeof (dtrace_ecbdesc_t), KM_SLEEP);
12041
12042 if ((pred = ecb->dted_pred.dtpdd_predicate) != NULL)
12043 dtrace_predicate_hold(pred);
12044
12045 for (act = ecb->dted_action; act != NULL; act = act->dtad_next)
12046 dtrace_actdesc_hold(act);
12047
12048 new->dted_action = ecb->dted_action;
12049 new->dted_pred = ecb->dted_pred;
12050 new->dted_probe = *pd;
12051 new->dted_uarg = ecb->dted_uarg;
12052
12053 dtrace_enabling_add(enab, new);
12054 }
12055
12056 static void
12057 dtrace_enabling_dump(dtrace_enabling_t *enab)
12058 {
12059 int i;
12060
12061 for (i = 0; i < enab->dten_ndesc; i++) {
12062 dtrace_probedesc_t *desc = &enab->dten_desc[i]->dted_probe;
12063
12064 cmn_err(CE_NOTE, "enabling probe %d (%s:%s:%s:%s)", i,
12065 desc->dtpd_provider, desc->dtpd_mod,
12066 desc->dtpd_func, desc->dtpd_name);
12067 }
12068 }
12069
12070 static void
12071 dtrace_enabling_destroy(dtrace_enabling_t *enab)
12072 {
12073 int i;
12074 dtrace_ecbdesc_t *ep;
12075 dtrace_vstate_t *vstate = enab->dten_vstate;
12076
12077 ASSERT(MUTEX_HELD(&dtrace_lock));
12078
12079 for (i = 0; i < enab->dten_ndesc; i++) {
12080 dtrace_actdesc_t *act, *next;
12081 dtrace_predicate_t *pred;
12082
12083 ep = enab->dten_desc[i];
12084
12085 if ((pred = ep->dted_pred.dtpdd_predicate) != NULL)
12086 dtrace_predicate_release(pred, vstate);
12087
12088 for (act = ep->dted_action; act != NULL; act = next) {
12089 next = act->dtad_next;
12090 dtrace_actdesc_release(act, vstate);
12091 }
12092
12093 kmem_free(ep, sizeof (dtrace_ecbdesc_t));
12094 }
12095
12096 kmem_free(enab->dten_desc,
12097 enab->dten_maxdesc * sizeof (dtrace_enabling_t *));
12098
12099 /*
12100 * If this was a retained enabling, decrement the dts_nretained count
12101 * and take it off of the dtrace_retained list.
12102 */
12103 if (enab->dten_prev != NULL || enab->dten_next != NULL ||
12104 dtrace_retained == enab) {
12105 ASSERT(enab->dten_vstate->dtvs_state != NULL);
12106 ASSERT(enab->dten_vstate->dtvs_state->dts_nretained > 0);
12107 enab->dten_vstate->dtvs_state->dts_nretained--;
12108 dtrace_retained_gen++;
12109 }
12110
12111 if (enab->dten_prev == NULL) {
12112 if (dtrace_retained == enab) {
12113 dtrace_retained = enab->dten_next;
12114
12115 if (dtrace_retained != NULL)
12116 dtrace_retained->dten_prev = NULL;
12117 }
12118 } else {
12119 ASSERT(enab != dtrace_retained);
12120 ASSERT(dtrace_retained != NULL);
12121 enab->dten_prev->dten_next = enab->dten_next;
12122 }
12123
12124 if (enab->dten_next != NULL) {
12125 ASSERT(dtrace_retained != NULL);
12126 enab->dten_next->dten_prev = enab->dten_prev;
12127 }
12128
12129 kmem_free(enab, sizeof (dtrace_enabling_t));
12130 }
12131
12132 static int
12133 dtrace_enabling_retain(dtrace_enabling_t *enab)
12134 {
12135 dtrace_state_t *state;
12136
12137 ASSERT(MUTEX_HELD(&dtrace_lock));
12138 ASSERT(enab->dten_next == NULL && enab->dten_prev == NULL);
12139 ASSERT(enab->dten_vstate != NULL);
12140
12141 state = enab->dten_vstate->dtvs_state;
12142 ASSERT(state != NULL);
12143
12144 /*
12145 * We only allow each state to retain dtrace_retain_max enablings.
12146 */
12147 if (state->dts_nretained >= dtrace_retain_max)
12148 return (ENOSPC);
12149
12150 state->dts_nretained++;
12151 dtrace_retained_gen++;
12152
12153 if (dtrace_retained == NULL) {
12154 dtrace_retained = enab;
12155 return (0);
12156 }
12157
12158 enab->dten_next = dtrace_retained;
12159 dtrace_retained->dten_prev = enab;
12160 dtrace_retained = enab;
12161
12162 return (0);
12163 }
12164
12165 static int
12166 dtrace_enabling_replicate(dtrace_state_t *state, dtrace_probedesc_t *match,
12167 dtrace_probedesc_t *create)
12168 {
12169 dtrace_enabling_t *new, *enab;
12170 int found = 0, err = ENOENT;
12171
12172 ASSERT(MUTEX_HELD(&dtrace_lock));
12173 ASSERT(strlen(match->dtpd_provider) < DTRACE_PROVNAMELEN);
12174 ASSERT(strlen(match->dtpd_mod) < DTRACE_MODNAMELEN);
12175 ASSERT(strlen(match->dtpd_func) < DTRACE_FUNCNAMELEN);
12176 ASSERT(strlen(match->dtpd_name) < DTRACE_NAMELEN);
12177
12178 new = dtrace_enabling_create(&state->dts_vstate);
12179
12180 /*
12181 * Iterate over all retained enablings, looking for enablings that
12182 * match the specified state.
12183 */
12184 for (enab = dtrace_retained; enab != NULL; enab = enab->dten_next) {
12185 int i;
12186
12187 /*
12188 * dtvs_state can only be NULL for helper enablings -- and
12189 * helper enablings can't be retained.
12190 */
12191 ASSERT(enab->dten_vstate->dtvs_state != NULL);
12192
12193 if (enab->dten_vstate->dtvs_state != state)
12194 continue;
12195
12196 /*
12197 * Now iterate over each probe description; we're looking for
12198 * an exact match to the specified probe description.
12199 */
12200 for (i = 0; i < enab->dten_ndesc; i++) {
12201 dtrace_ecbdesc_t *ep = enab->dten_desc[i];
12202 dtrace_probedesc_t *pd = &ep->dted_probe;
12203
12204 if (strcmp(pd->dtpd_provider, match->dtpd_provider))
12205 continue;
12206
12207 if (strcmp(pd->dtpd_mod, match->dtpd_mod))
12208 continue;
12209
12210 if (strcmp(pd->dtpd_func, match->dtpd_func))
12211 continue;
12212
12213 if (strcmp(pd->dtpd_name, match->dtpd_name))
12214 continue;
12215
12216 /*
12217 * We have a winning probe! Add it to our growing
12218 * enabling.
12219 */
12220 found = 1;
12221 dtrace_enabling_addlike(new, ep, create);
12222 }
12223 }
12224
12225 if (!found || (err = dtrace_enabling_retain(new)) != 0) {
12226 dtrace_enabling_destroy(new);
12227 return (err);
12228 }
12229
12230 return (0);
12231 }
12232
12233 static void
12234 dtrace_enabling_retract(dtrace_state_t *state)
12235 {
12236 dtrace_enabling_t *enab, *next;
12237
12238 ASSERT(MUTEX_HELD(&dtrace_lock));
12239
12240 /*
12241 * Iterate over all retained enablings, destroy the enablings retained
12242 * for the specified state.
12243 */
12244 for (enab = dtrace_retained; enab != NULL; enab = next) {
12245 next = enab->dten_next;
12246
12247 /*
12248 * dtvs_state can only be NULL for helper enablings -- and
12249 * helper enablings can't be retained.
12250 */
12251 ASSERT(enab->dten_vstate->dtvs_state != NULL);
12252
12253 if (enab->dten_vstate->dtvs_state == state) {
12254 ASSERT(state->dts_nretained > 0);
12255 dtrace_enabling_destroy(enab);
12256 }
12257 }
12258
12259 ASSERT(state->dts_nretained == 0);
12260 }
12261
12262 static int
12263 dtrace_enabling_match(dtrace_enabling_t *enab, int *nmatched)
12264 {
12265 int i = 0;
12266 int total_matched = 0, matched = 0;
12267
12268 ASSERT(MUTEX_HELD(&cpu_lock));
12269 ASSERT(MUTEX_HELD(&dtrace_lock));
12270
12271 for (i = 0; i < enab->dten_ndesc; i++) {
12272 dtrace_ecbdesc_t *ep = enab->dten_desc[i];
12273
12274 enab->dten_current = ep;
12275 enab->dten_error = 0;
12276
12277 /*
12278 * If a provider failed to enable a probe then get out and
12279 * let the consumer know we failed.
12280 */
12281 if ((matched = dtrace_probe_enable(&ep->dted_probe, enab)) < 0)
12282 return (EBUSY);
12283
12284 total_matched += matched;
12285
12286 if (enab->dten_error != 0) {
12287 /*
12288 * If we get an error half-way through enabling the
12289 * probes, we kick out -- perhaps with some number of
12290 * them enabled. Leaving enabled probes enabled may
12291 * be slightly confusing for user-level, but we expect
12292 * that no one will attempt to actually drive on in
12293 * the face of such errors. If this is an anonymous
12294 * enabling (indicated with a NULL nmatched pointer),
12295 * we cmn_err() a message. We aren't expecting to
12296 * get such an error -- such as it can exist at all,
12297 * it would be a result of corrupted DOF in the driver
12298 * properties.
12299 */
12300 if (nmatched == NULL) {
12301 cmn_err(CE_WARN, "dtrace_enabling_match() "
12302 "error on %p: %d", (void *)ep,
12303 enab->dten_error);
12304 }
12305
12306 return (enab->dten_error);
12307 }
12308 }
12309
12310 enab->dten_probegen = dtrace_probegen;
12311 if (nmatched != NULL)
12312 *nmatched = total_matched;
12313
12314 return (0);
12315 }
12316
12317 static void
12318 dtrace_enabling_matchall(void)
12319 {
12320 dtrace_enabling_t *enab;
12321
12322 mutex_enter(&cpu_lock);
12323 mutex_enter(&dtrace_lock);
12324
12325 /*
12326 * Iterate over all retained enablings to see if any probes match
12327 * against them. We only perform this operation on enablings for which
12328 * we have sufficient permissions by virtue of being in the global zone
12329 * or in the same zone as the DTrace client. Because we can be called
12330 * after dtrace_detach() has been called, we cannot assert that there
12331 * are retained enablings. We can safely load from dtrace_retained,
12332 * however: the taskq_destroy() at the end of dtrace_detach() will
12333 * block pending our completion.
12334 */
12335 for (enab = dtrace_retained; enab != NULL; enab = enab->dten_next) {
12336 dtrace_cred_t *dcr = &enab->dten_vstate->dtvs_state->dts_cred;
12337 cred_t *cr = dcr->dcr_cred;
12338 zoneid_t zone = cr != NULL ? crgetzoneid(cr) : 0;
12339
12340 if ((dcr->dcr_visible & DTRACE_CRV_ALLZONE) || (cr != NULL &&
12341 (zone == GLOBAL_ZONEID || getzoneid() == zone)))
12342 (void) dtrace_enabling_match(enab, NULL);
12343 }
12344
12345 mutex_exit(&dtrace_lock);
12346 mutex_exit(&cpu_lock);
12347 }
12348
12349 /*
12350 * If an enabling is to be enabled without having matched probes (that is, if
12351 * dtrace_state_go() is to be called on the underlying dtrace_state_t), the
12352 * enabling must be _primed_ by creating an ECB for every ECB description.
12353 * This must be done to assure that we know the number of speculations, the
12354 * number of aggregations, the minimum buffer size needed, etc. before we
12355 * transition out of DTRACE_ACTIVITY_INACTIVE. To do this without actually
12356 * enabling any probes, we create ECBs for every ECB decription, but with a
12357 * NULL probe -- which is exactly what this function does.
12358 */
12359 static void
12360 dtrace_enabling_prime(dtrace_state_t *state)
12361 {
12362 dtrace_enabling_t *enab;
12363 int i;
12364
12365 for (enab = dtrace_retained; enab != NULL; enab = enab->dten_next) {
12366 ASSERT(enab->dten_vstate->dtvs_state != NULL);
12367
12368 if (enab->dten_vstate->dtvs_state != state)
12369 continue;
12370
12371 /*
12372 * We don't want to prime an enabling more than once, lest
12373 * we allow a malicious user to induce resource exhaustion.
12374 * (The ECBs that result from priming an enabling aren't
12375 * leaked -- but they also aren't deallocated until the
12376 * consumer state is destroyed.)
12377 */
12378 if (enab->dten_primed)
12379 continue;
12380
12381 for (i = 0; i < enab->dten_ndesc; i++) {
12382 enab->dten_current = enab->dten_desc[i];
12383 (void) dtrace_probe_enable(NULL, enab);
12384 }
12385
12386 enab->dten_primed = 1;
12387 }
12388 }
12389
12390 /*
12391 * Called to indicate that probes should be provided due to retained
12392 * enablings. This is implemented in terms of dtrace_probe_provide(), but it
12393 * must take an initial lap through the enabling calling the dtps_provide()
12394 * entry point explicitly to allow for autocreated probes.
12395 */
12396 static void
12397 dtrace_enabling_provide(dtrace_provider_t *prv)
12398 {
12399 int i, all = 0;
12400 dtrace_probedesc_t desc;
12401 dtrace_genid_t gen;
12402
12403 ASSERT(MUTEX_HELD(&dtrace_lock));
12404 ASSERT(MUTEX_HELD(&dtrace_provider_lock));
12405
12406 if (prv == NULL) {
12407 all = 1;
12408 prv = dtrace_provider;
12409 }
12410
12411 do {
12412 dtrace_enabling_t *enab;
12413 void *parg = prv->dtpv_arg;
12414
12415 retry:
12416 gen = dtrace_retained_gen;
12417 for (enab = dtrace_retained; enab != NULL;
12418 enab = enab->dten_next) {
12419 for (i = 0; i < enab->dten_ndesc; i++) {
12420 desc = enab->dten_desc[i]->dted_probe;
12421 mutex_exit(&dtrace_lock);
12422 prv->dtpv_pops.dtps_provide(parg, &desc);
12423 mutex_enter(&dtrace_lock);
12424 /*
12425 * Process the retained enablings again if
12426 * they have changed while we weren't holding
12427 * dtrace_lock.
12428 */
12429 if (gen != dtrace_retained_gen)
12430 goto retry;
12431 }
12432 }
12433 } while (all && (prv = prv->dtpv_next) != NULL);
12434
12435 mutex_exit(&dtrace_lock);
12436 dtrace_probe_provide(NULL, all ? NULL : prv);
12437 mutex_enter(&dtrace_lock);
12438 }
12439
12440 /*
12441 * Called to reap ECBs that are attached to probes from defunct providers.
12442 */
12443 static void
12444 dtrace_enabling_reap(void)
12445 {
12446 dtrace_provider_t *prov;
12447 dtrace_probe_t *probe;
12448 dtrace_ecb_t *ecb;
12449 hrtime_t when;
12450 int i;
12451
12452 mutex_enter(&cpu_lock);
12453 mutex_enter(&dtrace_lock);
12454
12455 for (i = 0; i < dtrace_nprobes; i++) {
12456 if ((probe = dtrace_probes[i]) == NULL)
12457 continue;
12458
12459 if (probe->dtpr_ecb == NULL)
12460 continue;
12461
12462 prov = probe->dtpr_provider;
12463
12464 if ((when = prov->dtpv_defunct) == 0)
12465 continue;
12466
12467 /*
12468 * We have ECBs on a defunct provider: we want to reap these
12469 * ECBs to allow the provider to unregister. The destruction
12470 * of these ECBs must be done carefully: if we destroy the ECB
12471 * and the consumer later wishes to consume an EPID that
12472 * corresponds to the destroyed ECB (and if the EPID metadata
12473 * has not been previously consumed), the consumer will abort
12474 * processing on the unknown EPID. To reduce (but not, sadly,
12475 * eliminate) the possibility of this, we will only destroy an
12476 * ECB for a defunct provider if, for the state that
12477 * corresponds to the ECB:
12478 *
12479 * (a) There is no speculative tracing (which can effectively
12480 * cache an EPID for an arbitrary amount of time).
12481 *
12482 * (b) The principal buffers have been switched twice since the
12483 * provider became defunct.
12484 *
12485 * (c) The aggregation buffers are of zero size or have been
12486 * switched twice since the provider became defunct.
12487 *
12488 * We use dts_speculates to determine (a) and call a function
12489 * (dtrace_buffer_consumed()) to determine (b) and (c). Note
12490 * that as soon as we've been unable to destroy one of the ECBs
12491 * associated with the probe, we quit trying -- reaping is only
12492 * fruitful in as much as we can destroy all ECBs associated
12493 * with the defunct provider's probes.
12494 */
12495 while ((ecb = probe->dtpr_ecb) != NULL) {
12496 dtrace_state_t *state = ecb->dte_state;
12497 dtrace_buffer_t *buf = state->dts_buffer;
12498 dtrace_buffer_t *aggbuf = state->dts_aggbuffer;
12499
12500 if (state->dts_speculates)
12501 break;
12502
12503 if (!dtrace_buffer_consumed(buf, when))
12504 break;
12505
12506 if (!dtrace_buffer_consumed(aggbuf, when))
12507 break;
12508
12509 dtrace_ecb_disable(ecb);
12510 ASSERT(probe->dtpr_ecb != ecb);
12511 dtrace_ecb_destroy(ecb);
12512 }
12513 }
12514
12515 mutex_exit(&dtrace_lock);
12516 mutex_exit(&cpu_lock);
12517 }
12518
12519 /*
12520 * DTrace DOF Functions
12521 */
12522 /*ARGSUSED*/
12523 static void
12524 dtrace_dof_error(dof_hdr_t *dof, const char *str)
12525 {
12526 if (dtrace_err_verbose)
12527 cmn_err(CE_WARN, "failed to process DOF: %s", str);
12528
12529 #ifdef DTRACE_ERRDEBUG
12530 dtrace_errdebug(str);
12531 #endif
12532 }
12533
12534 /*
12535 * Create DOF out of a currently enabled state. Right now, we only create
12536 * DOF containing the run-time options -- but this could be expanded to create
12537 * complete DOF representing the enabled state.
12538 */
12539 static dof_hdr_t *
12540 dtrace_dof_create(dtrace_state_t *state)
12541 {
12542 dof_hdr_t *dof;
12543 dof_sec_t *sec;
12544 dof_optdesc_t *opt;
12545 int i, len = sizeof (dof_hdr_t) +
12546 roundup(sizeof (dof_sec_t), sizeof (uint64_t)) +
12547 sizeof (dof_optdesc_t) * DTRACEOPT_MAX;
12548
12549 ASSERT(MUTEX_HELD(&dtrace_lock));
12550
12551 dof = kmem_zalloc(len, KM_SLEEP);
12552 dof->dofh_ident[DOF_ID_MAG0] = DOF_MAG_MAG0;
12553 dof->dofh_ident[DOF_ID_MAG1] = DOF_MAG_MAG1;
12554 dof->dofh_ident[DOF_ID_MAG2] = DOF_MAG_MAG2;
12555 dof->dofh_ident[DOF_ID_MAG3] = DOF_MAG_MAG3;
12556
12557 dof->dofh_ident[DOF_ID_MODEL] = DOF_MODEL_NATIVE;
12558 dof->dofh_ident[DOF_ID_ENCODING] = DOF_ENCODE_NATIVE;
12559 dof->dofh_ident[DOF_ID_VERSION] = DOF_VERSION;
12560 dof->dofh_ident[DOF_ID_DIFVERS] = DIF_VERSION;
12561 dof->dofh_ident[DOF_ID_DIFIREG] = DIF_DIR_NREGS;
12562 dof->dofh_ident[DOF_ID_DIFTREG] = DIF_DTR_NREGS;
12563
12564 dof->dofh_flags = 0;
12565 dof->dofh_hdrsize = sizeof (dof_hdr_t);
12566 dof->dofh_secsize = sizeof (dof_sec_t);
12567 dof->dofh_secnum = 1; /* only DOF_SECT_OPTDESC */
12568 dof->dofh_secoff = sizeof (dof_hdr_t);
12569 dof->dofh_loadsz = len;
12570 dof->dofh_filesz = len;
12571 dof->dofh_pad = 0;
12572
12573 /*
12574 * Fill in the option section header...
12575 */
12576 sec = (dof_sec_t *)((uintptr_t)dof + sizeof (dof_hdr_t));
12577 sec->dofs_type = DOF_SECT_OPTDESC;
12578 sec->dofs_align = sizeof (uint64_t);
12579 sec->dofs_flags = DOF_SECF_LOAD;
12580 sec->dofs_entsize = sizeof (dof_optdesc_t);
12581
12582 opt = (dof_optdesc_t *)((uintptr_t)sec +
12583 roundup(sizeof (dof_sec_t), sizeof (uint64_t)));
12584
12585 sec->dofs_offset = (uintptr_t)opt - (uintptr_t)dof;
12586 sec->dofs_size = sizeof (dof_optdesc_t) * DTRACEOPT_MAX;
12587
12588 for (i = 0; i < DTRACEOPT_MAX; i++) {
12589 opt[i].dofo_option = i;
12590 opt[i].dofo_strtab = DOF_SECIDX_NONE;
12591 opt[i].dofo_value = state->dts_options[i];
12592 }
12593
12594 return (dof);
12595 }
12596
12597 static dof_hdr_t *
12598 dtrace_dof_copyin(uintptr_t uarg, int *errp)
12599 {
12600 dof_hdr_t hdr, *dof;
12601
12602 ASSERT(!MUTEX_HELD(&dtrace_lock));
12603
12604 /*
12605 * First, we're going to copyin() the sizeof (dof_hdr_t).
12606 */
12607 if (copyin((void *)uarg, &hdr, sizeof (hdr)) != 0) {
12608 dtrace_dof_error(NULL, "failed to copyin DOF header");
12609 *errp = EFAULT;
12610 return (NULL);
12611 }
12612
12613 /*
12614 * Now we'll allocate the entire DOF and copy it in -- provided
12615 * that the length isn't outrageous.
12616 */
12617 if (hdr.dofh_loadsz >= dtrace_dof_maxsize) {
12618 dtrace_dof_error(&hdr, "load size exceeds maximum");
12619 *errp = E2BIG;
12620 return (NULL);
12621 }
12622
12623 if (hdr.dofh_loadsz < sizeof (hdr)) {
12624 dtrace_dof_error(&hdr, "invalid load size");
12625 *errp = EINVAL;
12626 return (NULL);
12627 }
12628
12629 dof = kmem_alloc(hdr.dofh_loadsz, KM_SLEEP);
12630
12631 if (copyin((void *)uarg, dof, hdr.dofh_loadsz) != 0 ||
12632 dof->dofh_loadsz != hdr.dofh_loadsz) {
12633 kmem_free(dof, hdr.dofh_loadsz);
12634 *errp = EFAULT;
12635 return (NULL);
12636 }
12637
12638 return (dof);
12639 }
12640
12641 static dof_hdr_t *
12642 dtrace_dof_property(const char *name)
12643 {
12644 uchar_t *buf;
12645 uint64_t loadsz;
12646 unsigned int len, i;
12647 dof_hdr_t *dof;
12648
12649 /*
12650 * Unfortunately, array of values in .conf files are always (and
12651 * only) interpreted to be integer arrays. We must read our DOF
12652 * as an integer array, and then squeeze it into a byte array.
12653 */
12654 if (ddi_prop_lookup_int_array(DDI_DEV_T_ANY, dtrace_devi, 0,
12655 (char *)name, (int **)&buf, &len) != DDI_PROP_SUCCESS)
12656 return (NULL);
12657
12658 for (i = 0; i < len; i++)
12659 buf[i] = (uchar_t)(((int *)buf)[i]);
12660
12661 if (len < sizeof (dof_hdr_t)) {
12662 ddi_prop_free(buf);
12663 dtrace_dof_error(NULL, "truncated header");
12664 return (NULL);
12665 }
12666
12667 if (len < (loadsz = ((dof_hdr_t *)buf)->dofh_loadsz)) {
12668 ddi_prop_free(buf);
12669 dtrace_dof_error(NULL, "truncated DOF");
12670 return (NULL);
12671 }
12672
12673 if (loadsz >= dtrace_dof_maxsize) {
12674 ddi_prop_free(buf);
12675 dtrace_dof_error(NULL, "oversized DOF");
12676 return (NULL);
12677 }
12678
12679 dof = kmem_alloc(loadsz, KM_SLEEP);
12680 bcopy(buf, dof, loadsz);
12681 ddi_prop_free(buf);
12682
12683 return (dof);
12684 }
12685
12686 static void
12687 dtrace_dof_destroy(dof_hdr_t *dof)
12688 {
12689 kmem_free(dof, dof->dofh_loadsz);
12690 }
12691
12692 /*
12693 * Return the dof_sec_t pointer corresponding to a given section index. If the
12694 * index is not valid, dtrace_dof_error() is called and NULL is returned. If
12695 * a type other than DOF_SECT_NONE is specified, the header is checked against
12696 * this type and NULL is returned if the types do not match.
12697 */
12698 static dof_sec_t *
12699 dtrace_dof_sect(dof_hdr_t *dof, uint32_t type, dof_secidx_t i)
12700 {
12701 dof_sec_t *sec = (dof_sec_t *)(uintptr_t)
12702 ((uintptr_t)dof + dof->dofh_secoff + i * dof->dofh_secsize);
12703
12704 if (i >= dof->dofh_secnum) {
12705 dtrace_dof_error(dof, "referenced section index is invalid");
12706 return (NULL);
12707 }
12708
12709 if (!(sec->dofs_flags & DOF_SECF_LOAD)) {
12710 dtrace_dof_error(dof, "referenced section is not loadable");
12711 return (NULL);
12712 }
12713
12714 if (type != DOF_SECT_NONE && type != sec->dofs_type) {
12715 dtrace_dof_error(dof, "referenced section is the wrong type");
12716 return (NULL);
12717 }
12718
12719 return (sec);
12720 }
12721
12722 static dtrace_probedesc_t *
12723 dtrace_dof_probedesc(dof_hdr_t *dof, dof_sec_t *sec, dtrace_probedesc_t *desc)
12724 {
12725 dof_probedesc_t *probe;
12726 dof_sec_t *strtab;
12727 uintptr_t daddr = (uintptr_t)dof;
12728 uintptr_t str;
12729 size_t size;
12730
12731 if (sec->dofs_type != DOF_SECT_PROBEDESC) {
12732 dtrace_dof_error(dof, "invalid probe section");
12733 return (NULL);
12734 }
12735
12736 if (sec->dofs_align != sizeof (dof_secidx_t)) {
12737 dtrace_dof_error(dof, "bad alignment in probe description");
12738 return (NULL);
12739 }
12740
12741 if (sec->dofs_offset + sizeof (dof_probedesc_t) > dof->dofh_loadsz) {
12742 dtrace_dof_error(dof, "truncated probe description");
12743 return (NULL);
12744 }
12745
12746 probe = (dof_probedesc_t *)(uintptr_t)(daddr + sec->dofs_offset);
12747 strtab = dtrace_dof_sect(dof, DOF_SECT_STRTAB, probe->dofp_strtab);
12748
12749 if (strtab == NULL)
12750 return (NULL);
12751
12752 str = daddr + strtab->dofs_offset;
12753 size = strtab->dofs_size;
12754
12755 if (probe->dofp_provider >= strtab->dofs_size) {
12756 dtrace_dof_error(dof, "corrupt probe provider");
12757 return (NULL);
12758 }
12759
12760 (void) strncpy(desc->dtpd_provider,
12761 (char *)(str + probe->dofp_provider),
12762 MIN(DTRACE_PROVNAMELEN - 1, size - probe->dofp_provider));
12763
12764 if (probe->dofp_mod >= strtab->dofs_size) {
12765 dtrace_dof_error(dof, "corrupt probe module");
12766 return (NULL);
12767 }
12768
12769 (void) strncpy(desc->dtpd_mod, (char *)(str + probe->dofp_mod),
12770 MIN(DTRACE_MODNAMELEN - 1, size - probe->dofp_mod));
12771
12772 if (probe->dofp_func >= strtab->dofs_size) {
12773 dtrace_dof_error(dof, "corrupt probe function");
12774 return (NULL);
12775 }
12776
12777 (void) strncpy(desc->dtpd_func, (char *)(str + probe->dofp_func),
12778 MIN(DTRACE_FUNCNAMELEN - 1, size - probe->dofp_func));
12779
12780 if (probe->dofp_name >= strtab->dofs_size) {
12781 dtrace_dof_error(dof, "corrupt probe name");
12782 return (NULL);
12783 }
12784
12785 (void) strncpy(desc->dtpd_name, (char *)(str + probe->dofp_name),
12786 MIN(DTRACE_NAMELEN - 1, size - probe->dofp_name));
12787
12788 return (desc);
12789 }
12790
12791 static dtrace_difo_t *
12792 dtrace_dof_difo(dof_hdr_t *dof, dof_sec_t *sec, dtrace_vstate_t *vstate,
12793 cred_t *cr)
12794 {
12795 dtrace_difo_t *dp;
12796 size_t ttl = 0;
12797 dof_difohdr_t *dofd;
12798 uintptr_t daddr = (uintptr_t)dof;
12799 size_t max = dtrace_difo_maxsize;
12800 int i, l, n;
12801
12802 static const struct {
12803 int section;
12804 int bufoffs;
12805 int lenoffs;
12806 int entsize;
12807 int align;
12808 const char *msg;
12809 } difo[] = {
12810 { DOF_SECT_DIF, offsetof(dtrace_difo_t, dtdo_buf),
12811 offsetof(dtrace_difo_t, dtdo_len), sizeof (dif_instr_t),
12812 sizeof (dif_instr_t), "multiple DIF sections" },
12813
12814 { DOF_SECT_INTTAB, offsetof(dtrace_difo_t, dtdo_inttab),
12815 offsetof(dtrace_difo_t, dtdo_intlen), sizeof (uint64_t),
12816 sizeof (uint64_t), "multiple integer tables" },
12817
12818 { DOF_SECT_STRTAB, offsetof(dtrace_difo_t, dtdo_strtab),
12819 offsetof(dtrace_difo_t, dtdo_strlen), 0,
12820 sizeof (char), "multiple string tables" },
12821
12822 { DOF_SECT_VARTAB, offsetof(dtrace_difo_t, dtdo_vartab),
12823 offsetof(dtrace_difo_t, dtdo_varlen), sizeof (dtrace_difv_t),
12824 sizeof (uint_t), "multiple variable tables" },
12825
12826 { DOF_SECT_NONE, 0, 0, 0, NULL }
12827 };
12828
12829 if (sec->dofs_type != DOF_SECT_DIFOHDR) {
12830 dtrace_dof_error(dof, "invalid DIFO header section");
12831 return (NULL);
12832 }
12833
12834 if (sec->dofs_align != sizeof (dof_secidx_t)) {
12835 dtrace_dof_error(dof, "bad alignment in DIFO header");
12836 return (NULL);
12837 }
12838
12839 if (sec->dofs_size < sizeof (dof_difohdr_t) ||
12840 sec->dofs_size % sizeof (dof_secidx_t)) {
12841 dtrace_dof_error(dof, "bad size in DIFO header");
12842 return (NULL);
12843 }
12844
12845 dofd = (dof_difohdr_t *)(uintptr_t)(daddr + sec->dofs_offset);
12846 n = (sec->dofs_size - sizeof (*dofd)) / sizeof (dof_secidx_t) + 1;
12847
12848 dp = kmem_zalloc(sizeof (dtrace_difo_t), KM_SLEEP);
12849 dp->dtdo_rtype = dofd->dofd_rtype;
12850
12851 for (l = 0; l < n; l++) {
12852 dof_sec_t *subsec;
12853 void **bufp;
12854 uint32_t *lenp;
12855
12856 if ((subsec = dtrace_dof_sect(dof, DOF_SECT_NONE,
12857 dofd->dofd_links[l])) == NULL)
12858 goto err; /* invalid section link */
12859
12860 if (ttl + subsec->dofs_size > max) {
12861 dtrace_dof_error(dof, "exceeds maximum size");
12862 goto err;
12863 }
12864
12865 ttl += subsec->dofs_size;
12866
12867 for (i = 0; difo[i].section != DOF_SECT_NONE; i++) {
12868 if (subsec->dofs_type != difo[i].section)
12869 continue;
12870
12871 if (!(subsec->dofs_flags & DOF_SECF_LOAD)) {
12872 dtrace_dof_error(dof, "section not loaded");
12873 goto err;
12874 }
12875
12876 if (subsec->dofs_align != difo[i].align) {
12877 dtrace_dof_error(dof, "bad alignment");
12878 goto err;
12879 }
12880
12881 bufp = (void **)((uintptr_t)dp + difo[i].bufoffs);
12882 lenp = (uint32_t *)((uintptr_t)dp + difo[i].lenoffs);
12883
12884 if (*bufp != NULL) {
12885 dtrace_dof_error(dof, difo[i].msg);
12886 goto err;
12887 }
12888
12889 if (difo[i].entsize != subsec->dofs_entsize) {
12890 dtrace_dof_error(dof, "entry size mismatch");
12891 goto err;
12892 }
12893
12894 if (subsec->dofs_entsize != 0 &&
12895 (subsec->dofs_size % subsec->dofs_entsize) != 0) {
12896 dtrace_dof_error(dof, "corrupt entry size");
12897 goto err;
12898 }
12899
12900 *lenp = subsec->dofs_size;
12901 *bufp = kmem_alloc(subsec->dofs_size, KM_SLEEP);
12902 bcopy((char *)(uintptr_t)(daddr + subsec->dofs_offset),
12903 *bufp, subsec->dofs_size);
12904
12905 if (subsec->dofs_entsize != 0)
12906 *lenp /= subsec->dofs_entsize;
12907
12908 break;
12909 }
12910
12911 /*
12912 * If we encounter a loadable DIFO sub-section that is not
12913 * known to us, assume this is a broken program and fail.
12914 */
12915 if (difo[i].section == DOF_SECT_NONE &&
12916 (subsec->dofs_flags & DOF_SECF_LOAD)) {
12917 dtrace_dof_error(dof, "unrecognized DIFO subsection");
12918 goto err;
12919 }
12920 }
12921
12922 if (dp->dtdo_buf == NULL) {
12923 /*
12924 * We can't have a DIF object without DIF text.
12925 */
12926 dtrace_dof_error(dof, "missing DIF text");
12927 goto err;
12928 }
12929
12930 /*
12931 * Before we validate the DIF object, run through the variable table
12932 * looking for the strings -- if any of their size are under, we'll set
12933 * their size to be the system-wide default string size. Note that
12934 * this should _not_ happen if the "strsize" option has been set --
12935 * in this case, the compiler should have set the size to reflect the
12936 * setting of the option.
12937 */
12938 for (i = 0; i < dp->dtdo_varlen; i++) {
12939 dtrace_difv_t *v = &dp->dtdo_vartab[i];
12940 dtrace_diftype_t *t = &v->dtdv_type;
12941
12942 if (v->dtdv_id < DIF_VAR_OTHER_UBASE)
12943 continue;
12944
12945 if (t->dtdt_kind == DIF_TYPE_STRING && t->dtdt_size == 0)
12946 t->dtdt_size = dtrace_strsize_default;
12947 }
12948
12949 if (dtrace_difo_validate(dp, vstate, DIF_DIR_NREGS, cr) != 0)
12950 goto err;
12951
12952 dtrace_difo_init(dp, vstate);
12953 return (dp);
12954
12955 err:
12956 kmem_free(dp->dtdo_buf, dp->dtdo_len * sizeof (dif_instr_t));
12957 kmem_free(dp->dtdo_inttab, dp->dtdo_intlen * sizeof (uint64_t));
12958 kmem_free(dp->dtdo_strtab, dp->dtdo_strlen);
12959 kmem_free(dp->dtdo_vartab, dp->dtdo_varlen * sizeof (dtrace_difv_t));
12960
12961 kmem_free(dp, sizeof (dtrace_difo_t));
12962 return (NULL);
12963 }
12964
12965 static dtrace_predicate_t *
12966 dtrace_dof_predicate(dof_hdr_t *dof, dof_sec_t *sec, dtrace_vstate_t *vstate,
12967 cred_t *cr)
12968 {
12969 dtrace_difo_t *dp;
12970
12971 if ((dp = dtrace_dof_difo(dof, sec, vstate, cr)) == NULL)
12972 return (NULL);
12973
12974 return (dtrace_predicate_create(dp));
12975 }
12976
12977 static dtrace_actdesc_t *
12978 dtrace_dof_actdesc(dof_hdr_t *dof, dof_sec_t *sec, dtrace_vstate_t *vstate,
12979 cred_t *cr)
12980 {
12981 dtrace_actdesc_t *act, *first = NULL, *last = NULL, *next;
12982 dof_actdesc_t *desc;
12983 dof_sec_t *difosec;
12984 size_t offs;
12985 uintptr_t daddr = (uintptr_t)dof;
12986 uint64_t arg;
12987 dtrace_actkind_t kind;
12988
12989 if (sec->dofs_type != DOF_SECT_ACTDESC) {
12990 dtrace_dof_error(dof, "invalid action section");
12991 return (NULL);
12992 }
12993
12994 if (sec->dofs_offset + sizeof (dof_actdesc_t) > dof->dofh_loadsz) {
12995 dtrace_dof_error(dof, "truncated action description");
12996 return (NULL);
12997 }
12998
12999 if (sec->dofs_align != sizeof (uint64_t)) {
13000 dtrace_dof_error(dof, "bad alignment in action description");
13001 return (NULL);
13002 }
13003
13004 if (sec->dofs_size < sec->dofs_entsize) {
13005 dtrace_dof_error(dof, "section entry size exceeds total size");
13006 return (NULL);
13007 }
13008
13009 if (sec->dofs_entsize != sizeof (dof_actdesc_t)) {
13010 dtrace_dof_error(dof, "bad entry size in action description");
13011 return (NULL);
13012 }
13013
13014 if (sec->dofs_size / sec->dofs_entsize > dtrace_actions_max) {
13015 dtrace_dof_error(dof, "actions exceed dtrace_actions_max");
13016 return (NULL);
13017 }
13018
13019 for (offs = 0; offs < sec->dofs_size; offs += sec->dofs_entsize) {
13020 desc = (dof_actdesc_t *)(daddr +
13021 (uintptr_t)sec->dofs_offset + offs);
13022 kind = (dtrace_actkind_t)desc->dofa_kind;
13023
13024 if ((DTRACEACT_ISPRINTFLIKE(kind) &&
13025 (kind != DTRACEACT_PRINTA ||
13026 desc->dofa_strtab != DOF_SECIDX_NONE)) ||
13027 (kind == DTRACEACT_DIFEXPR &&
13028 desc->dofa_strtab != DOF_SECIDX_NONE)) {
13029 dof_sec_t *strtab;
13030 char *str, *fmt;
13031 uint64_t i;
13032
13033 /*
13034 * The argument to these actions is an index into the
13035 * DOF string table. For printf()-like actions, this
13036 * is the format string. For print(), this is the
13037 * CTF type of the expression result.
13038 */
13039 if ((strtab = dtrace_dof_sect(dof,
13040 DOF_SECT_STRTAB, desc->dofa_strtab)) == NULL)
13041 goto err;
13042
13043 str = (char *)((uintptr_t)dof +
13044 (uintptr_t)strtab->dofs_offset);
13045
13046 for (i = desc->dofa_arg; i < strtab->dofs_size; i++) {
13047 if (str[i] == '\0')
13048 break;
13049 }
13050
13051 if (i >= strtab->dofs_size) {
13052 dtrace_dof_error(dof, "bogus format string");
13053 goto err;
13054 }
13055
13056 if (i == desc->dofa_arg) {
13057 dtrace_dof_error(dof, "empty format string");
13058 goto err;
13059 }
13060
13061 i -= desc->dofa_arg;
13062 fmt = kmem_alloc(i + 1, KM_SLEEP);
13063 bcopy(&str[desc->dofa_arg], fmt, i + 1);
13064 arg = (uint64_t)(uintptr_t)fmt;
13065 } else {
13066 if (kind == DTRACEACT_PRINTA) {
13067 ASSERT(desc->dofa_strtab == DOF_SECIDX_NONE);
13068 arg = 0;
13069 } else {
13070 arg = desc->dofa_arg;
13071 }
13072 }
13073
13074 act = dtrace_actdesc_create(kind, desc->dofa_ntuple,
13075 desc->dofa_uarg, arg);
13076
13077 if (last != NULL) {
13078 last->dtad_next = act;
13079 } else {
13080 first = act;
13081 }
13082
13083 last = act;
13084
13085 if (desc->dofa_difo == DOF_SECIDX_NONE)
13086 continue;
13087
13088 if ((difosec = dtrace_dof_sect(dof,
13089 DOF_SECT_DIFOHDR, desc->dofa_difo)) == NULL)
13090 goto err;
13091
13092 act->dtad_difo = dtrace_dof_difo(dof, difosec, vstate, cr);
13093
13094 if (act->dtad_difo == NULL)
13095 goto err;
13096 }
13097
13098 ASSERT(first != NULL);
13099 return (first);
13100
13101 err:
13102 for (act = first; act != NULL; act = next) {
13103 next = act->dtad_next;
13104 dtrace_actdesc_release(act, vstate);
13105 }
13106
13107 return (NULL);
13108 }
13109
13110 static dtrace_ecbdesc_t *
13111 dtrace_dof_ecbdesc(dof_hdr_t *dof, dof_sec_t *sec, dtrace_vstate_t *vstate,
13112 cred_t *cr)
13113 {
13114 dtrace_ecbdesc_t *ep;
13115 dof_ecbdesc_t *ecb;
13116 dtrace_probedesc_t *desc;
13117 dtrace_predicate_t *pred = NULL;
13118
13119 if (sec->dofs_size < sizeof (dof_ecbdesc_t)) {
13120 dtrace_dof_error(dof, "truncated ECB description");
13121 return (NULL);
13122 }
13123
13124 if (sec->dofs_align != sizeof (uint64_t)) {
13125 dtrace_dof_error(dof, "bad alignment in ECB description");
13126 return (NULL);
13127 }
13128
13129 ecb = (dof_ecbdesc_t *)((uintptr_t)dof + (uintptr_t)sec->dofs_offset);
13130 sec = dtrace_dof_sect(dof, DOF_SECT_PROBEDESC, ecb->dofe_probes);
13131
13132 if (sec == NULL)
13133 return (NULL);
13134
13135 ep = kmem_zalloc(sizeof (dtrace_ecbdesc_t), KM_SLEEP);
13136 ep->dted_uarg = ecb->dofe_uarg;
13137 desc = &ep->dted_probe;
13138
13139 if (dtrace_dof_probedesc(dof, sec, desc) == NULL)
13140 goto err;
13141
13142 if (ecb->dofe_pred != DOF_SECIDX_NONE) {
13143 if ((sec = dtrace_dof_sect(dof,
13144 DOF_SECT_DIFOHDR, ecb->dofe_pred)) == NULL)
13145 goto err;
13146
13147 if ((pred = dtrace_dof_predicate(dof, sec, vstate, cr)) == NULL)
13148 goto err;
13149
13150 ep->dted_pred.dtpdd_predicate = pred;
13151 }
13152
13153 if (ecb->dofe_actions != DOF_SECIDX_NONE) {
13154 if ((sec = dtrace_dof_sect(dof,
13155 DOF_SECT_ACTDESC, ecb->dofe_actions)) == NULL)
13156 goto err;
13157
13158 ep->dted_action = dtrace_dof_actdesc(dof, sec, vstate, cr);
13159
13160 if (ep->dted_action == NULL)
13161 goto err;
13162 }
13163
13164 return (ep);
13165
13166 err:
13167 if (pred != NULL)
13168 dtrace_predicate_release(pred, vstate);
13169 kmem_free(ep, sizeof (dtrace_ecbdesc_t));
13170 return (NULL);
13171 }
13172
13173 /*
13174 * Apply the relocations from the specified 'sec' (a DOF_SECT_URELHDR) to the
13175 * specified DOF. At present, this amounts to simply adding 'ubase' to the
13176 * site of any user SETX relocations to account for load object base address.
13177 * In the future, if we need other relocations, this function can be extended.
13178 */
13179 static int
13180 dtrace_dof_relocate(dof_hdr_t *dof, dof_sec_t *sec, uint64_t ubase)
13181 {
13182 uintptr_t daddr = (uintptr_t)dof;
13183 uintptr_t ts_end;
13184 dof_relohdr_t *dofr =
13185 (dof_relohdr_t *)(uintptr_t)(daddr + sec->dofs_offset);
13186 dof_sec_t *ss, *rs, *ts;
13187 dof_relodesc_t *r;
13188 uint_t i, n;
13189
13190 if (sec->dofs_size < sizeof (dof_relohdr_t) ||
13191 sec->dofs_align != sizeof (dof_secidx_t)) {
13192 dtrace_dof_error(dof, "invalid relocation header");
13193 return (-1);
13194 }
13195
13196 ss = dtrace_dof_sect(dof, DOF_SECT_STRTAB, dofr->dofr_strtab);
13197 rs = dtrace_dof_sect(dof, DOF_SECT_RELTAB, dofr->dofr_relsec);
13198 ts = dtrace_dof_sect(dof, DOF_SECT_NONE, dofr->dofr_tgtsec);
13199 ts_end = (uintptr_t)ts + sizeof (dof_sec_t);
13200
13201 if (ss == NULL || rs == NULL || ts == NULL)
13202 return (-1); /* dtrace_dof_error() has been called already */
13203
13204 if (rs->dofs_entsize < sizeof (dof_relodesc_t) ||
13205 rs->dofs_align != sizeof (uint64_t)) {
13206 dtrace_dof_error(dof, "invalid relocation section");
13207 return (-1);
13208 }
13209
13210 r = (dof_relodesc_t *)(uintptr_t)(daddr + rs->dofs_offset);
13211 n = rs->dofs_size / rs->dofs_entsize;
13212
13213 for (i = 0; i < n; i++) {
13214 uintptr_t taddr = daddr + ts->dofs_offset + r->dofr_offset;
13215
13216 switch (r->dofr_type) {
13217 case DOF_RELO_NONE:
13218 break;
13219 case DOF_RELO_SETX:
13220 if (r->dofr_offset >= ts->dofs_size || r->dofr_offset +
13221 sizeof (uint64_t) > ts->dofs_size) {
13222 dtrace_dof_error(dof, "bad relocation offset");
13223 return (-1);
13224 }
13225
13226 if (taddr >= (uintptr_t)ts && taddr < ts_end) {
13227 dtrace_dof_error(dof, "bad relocation offset");
13228 return (-1);
13229 }
13230
13231 if (!IS_P2ALIGNED(taddr, sizeof (uint64_t))) {
13232 dtrace_dof_error(dof, "misaligned setx relo");
13233 return (-1);
13234 }
13235
13236 *(uint64_t *)taddr += ubase;
13237 break;
13238 default:
13239 dtrace_dof_error(dof, "invalid relocation type");
13240 return (-1);
13241 }
13242
13243 r = (dof_relodesc_t *)((uintptr_t)r + rs->dofs_entsize);
13244 }
13245
13246 return (0);
13247 }
13248
13249 /*
13250 * The dof_hdr_t passed to dtrace_dof_slurp() should be a partially validated
13251 * header: it should be at the front of a memory region that is at least
13252 * sizeof (dof_hdr_t) in size -- and then at least dof_hdr.dofh_loadsz in
13253 * size. It need not be validated in any other way.
13254 */
13255 static int
13256 dtrace_dof_slurp(dof_hdr_t *dof, dtrace_vstate_t *vstate, cred_t *cr,
13257 dtrace_enabling_t **enabp, uint64_t ubase, int noprobes)
13258 {
13259 uint64_t len = dof->dofh_loadsz, seclen;
13260 uintptr_t daddr = (uintptr_t)dof;
13261 dtrace_ecbdesc_t *ep;
13262 dtrace_enabling_t *enab;
13263 uint_t i;
13264
13265 ASSERT(MUTEX_HELD(&dtrace_lock));
13266 ASSERT(dof->dofh_loadsz >= sizeof (dof_hdr_t));
13267
13268 /*
13269 * Check the DOF header identification bytes. In addition to checking
13270 * valid settings, we also verify that unused bits/bytes are zeroed so
13271 * we can use them later without fear of regressing existing binaries.
13272 */
13273 if (bcmp(&dof->dofh_ident[DOF_ID_MAG0],
13274 DOF_MAG_STRING, DOF_MAG_STRLEN) != 0) {
13275 dtrace_dof_error(dof, "DOF magic string mismatch");
13276 return (-1);
13277 }
13278
13279 if (dof->dofh_ident[DOF_ID_MODEL] != DOF_MODEL_ILP32 &&
13280 dof->dofh_ident[DOF_ID_MODEL] != DOF_MODEL_LP64) {
13281 dtrace_dof_error(dof, "DOF has invalid data model");
13282 return (-1);
13283 }
13284
13285 if (dof->dofh_ident[DOF_ID_ENCODING] != DOF_ENCODE_NATIVE) {
13286 dtrace_dof_error(dof, "DOF encoding mismatch");
13287 return (-1);
13288 }
13289
13290 if (dof->dofh_ident[DOF_ID_VERSION] != DOF_VERSION_1 &&
13291 dof->dofh_ident[DOF_ID_VERSION] != DOF_VERSION_2) {
13292 dtrace_dof_error(dof, "DOF version mismatch");
13293 return (-1);
13294 }
13295
13296 if (dof->dofh_ident[DOF_ID_DIFVERS] != DIF_VERSION_2) {
13297 dtrace_dof_error(dof, "DOF uses unsupported instruction set");
13298 return (-1);
13299 }
13300
13301 if (dof->dofh_ident[DOF_ID_DIFIREG] > DIF_DIR_NREGS) {
13302 dtrace_dof_error(dof, "DOF uses too many integer registers");
13303 return (-1);
13304 }
13305
13306 if (dof->dofh_ident[DOF_ID_DIFTREG] > DIF_DTR_NREGS) {
13307 dtrace_dof_error(dof, "DOF uses too many tuple registers");
13308 return (-1);
13309 }
13310
13311 for (i = DOF_ID_PAD; i < DOF_ID_SIZE; i++) {
13312 if (dof->dofh_ident[i] != 0) {
13313 dtrace_dof_error(dof, "DOF has invalid ident byte set");
13314 return (-1);
13315 }
13316 }
13317
13318 if (dof->dofh_flags & ~DOF_FL_VALID) {
13319 dtrace_dof_error(dof, "DOF has invalid flag bits set");
13320 return (-1);
13321 }
13322
13323 if (dof->dofh_secsize == 0) {
13324 dtrace_dof_error(dof, "zero section header size");
13325 return (-1);
13326 }
13327
13328 /*
13329 * Check that the section headers don't exceed the amount of DOF
13330 * data. Note that we cast the section size and number of sections
13331 * to uint64_t's to prevent possible overflow in the multiplication.
13332 */
13333 seclen = (uint64_t)dof->dofh_secnum * (uint64_t)dof->dofh_secsize;
13334
13335 if (dof->dofh_secoff > len || seclen > len ||
13336 dof->dofh_secoff + seclen > len) {
13337 dtrace_dof_error(dof, "truncated section headers");
13338 return (-1);
13339 }
13340
13341 if (!IS_P2ALIGNED(dof->dofh_secoff, sizeof (uint64_t))) {
13342 dtrace_dof_error(dof, "misaligned section headers");
13343 return (-1);
13344 }
13345
13346 if (!IS_P2ALIGNED(dof->dofh_secsize, sizeof (uint64_t))) {
13347 dtrace_dof_error(dof, "misaligned section size");
13348 return (-1);
13349 }
13350
13351 /*
13352 * Take an initial pass through the section headers to be sure that
13353 * the headers don't have stray offsets. If the 'noprobes' flag is
13354 * set, do not permit sections relating to providers, probes, or args.
13355 */
13356 for (i = 0; i < dof->dofh_secnum; i++) {
13357 dof_sec_t *sec = (dof_sec_t *)(daddr +
13358 (uintptr_t)dof->dofh_secoff + i * dof->dofh_secsize);
13359
13360 if (noprobes) {
13361 switch (sec->dofs_type) {
13362 case DOF_SECT_PROVIDER:
13363 case DOF_SECT_PROBES:
13364 case DOF_SECT_PRARGS:
13365 case DOF_SECT_PROFFS:
13366 dtrace_dof_error(dof, "illegal sections "
13367 "for enabling");
13368 return (-1);
13369 }
13370 }
13371
13372 if (DOF_SEC_ISLOADABLE(sec->dofs_type) &&
13373 !(sec->dofs_flags & DOF_SECF_LOAD)) {
13374 dtrace_dof_error(dof, "loadable section with load "
13375 "flag unset");
13376 return (-1);
13377 }
13378
13379 if (!(sec->dofs_flags & DOF_SECF_LOAD))
13380 continue; /* just ignore non-loadable sections */
13381
13382 if (!ISP2(sec->dofs_align)) {
13383 dtrace_dof_error(dof, "bad section alignment");
13384 return (-1);
13385 }
13386
13387 if (sec->dofs_offset & (sec->dofs_align - 1)) {
13388 dtrace_dof_error(dof, "misaligned section");
13389 return (-1);
13390 }
13391
13392 if (sec->dofs_offset > len || sec->dofs_size > len ||
13393 sec->dofs_offset + sec->dofs_size > len) {
13394 dtrace_dof_error(dof, "corrupt section header");
13395 return (-1);
13396 }
13397
13398 if (sec->dofs_type == DOF_SECT_STRTAB && *((char *)daddr +
13399 sec->dofs_offset + sec->dofs_size - 1) != '\0') {
13400 dtrace_dof_error(dof, "non-terminating string table");
13401 return (-1);
13402 }
13403 }
13404
13405 /*
13406 * Take a second pass through the sections and locate and perform any
13407 * relocations that are present. We do this after the first pass to
13408 * be sure that all sections have had their headers validated.
13409 */
13410 for (i = 0; i < dof->dofh_secnum; i++) {
13411 dof_sec_t *sec = (dof_sec_t *)(daddr +
13412 (uintptr_t)dof->dofh_secoff + i * dof->dofh_secsize);
13413
13414 if (!(sec->dofs_flags & DOF_SECF_LOAD))
13415 continue; /* skip sections that are not loadable */
13416
13417 switch (sec->dofs_type) {
13418 case DOF_SECT_URELHDR:
13419 if (dtrace_dof_relocate(dof, sec, ubase) != 0)
13420 return (-1);
13421 break;
13422 }
13423 }
13424
13425 if ((enab = *enabp) == NULL)
13426 enab = *enabp = dtrace_enabling_create(vstate);
13427
13428 for (i = 0; i < dof->dofh_secnum; i++) {
13429 dof_sec_t *sec = (dof_sec_t *)(daddr +
13430 (uintptr_t)dof->dofh_secoff + i * dof->dofh_secsize);
13431
13432 if (sec->dofs_type != DOF_SECT_ECBDESC)
13433 continue;
13434
13435 if ((ep = dtrace_dof_ecbdesc(dof, sec, vstate, cr)) == NULL) {
13436 dtrace_enabling_destroy(enab);
13437 *enabp = NULL;
13438 return (-1);
13439 }
13440
13441 dtrace_enabling_add(enab, ep);
13442 }
13443
13444 return (0);
13445 }
13446
13447 /*
13448 * Process DOF for any options. This routine assumes that the DOF has been
13449 * at least processed by dtrace_dof_slurp().
13450 */
13451 static int
13452 dtrace_dof_options(dof_hdr_t *dof, dtrace_state_t *state)
13453 {
13454 int i, rval;
13455 uint32_t entsize;
13456 size_t offs;
13457 dof_optdesc_t *desc;
13458
13459 for (i = 0; i < dof->dofh_secnum; i++) {
13460 dof_sec_t *sec = (dof_sec_t *)((uintptr_t)dof +
13461 (uintptr_t)dof->dofh_secoff + i * dof->dofh_secsize);
13462
13463 if (sec->dofs_type != DOF_SECT_OPTDESC)
13464 continue;
13465
13466 if (sec->dofs_align != sizeof (uint64_t)) {
13467 dtrace_dof_error(dof, "bad alignment in "
13468 "option description");
13469 return (EINVAL);
13470 }
13471
13472 if ((entsize = sec->dofs_entsize) == 0) {
13473 dtrace_dof_error(dof, "zeroed option entry size");
13474 return (EINVAL);
13475 }
13476
13477 if (entsize < sizeof (dof_optdesc_t)) {
13478 dtrace_dof_error(dof, "bad option entry size");
13479 return (EINVAL);
13480 }
13481
13482 for (offs = 0; offs < sec->dofs_size; offs += entsize) {
13483 desc = (dof_optdesc_t *)((uintptr_t)dof +
13484 (uintptr_t)sec->dofs_offset + offs);
13485
13486 if (desc->dofo_strtab != DOF_SECIDX_NONE) {
13487 dtrace_dof_error(dof, "non-zero option string");
13488 return (EINVAL);
13489 }
13490
13491 if (desc->dofo_value == DTRACEOPT_UNSET) {
13492 dtrace_dof_error(dof, "unset option");
13493 return (EINVAL);
13494 }
13495
13496 if ((rval = dtrace_state_option(state,
13497 desc->dofo_option, desc->dofo_value)) != 0) {
13498 dtrace_dof_error(dof, "rejected option");
13499 return (rval);
13500 }
13501 }
13502 }
13503
13504 return (0);
13505 }
13506
13507 /*
13508 * DTrace Consumer State Functions
13509 */
13510 int
13511 dtrace_dstate_init(dtrace_dstate_t *dstate, size_t size)
13512 {
13513 size_t hashsize, maxper, min, chunksize = dstate->dtds_chunksize;
13514 void *base;
13515 uintptr_t limit;
13516 dtrace_dynvar_t *dvar, *next, *start;
13517 int i;
13518
13519 ASSERT(MUTEX_HELD(&dtrace_lock));
13520 ASSERT(dstate->dtds_base == NULL && dstate->dtds_percpu == NULL);
13521
13522 bzero(dstate, sizeof (dtrace_dstate_t));
13523
13524 if ((dstate->dtds_chunksize = chunksize) == 0)
13525 dstate->dtds_chunksize = DTRACE_DYNVAR_CHUNKSIZE;
13526
13527 VERIFY(dstate->dtds_chunksize < LONG_MAX);
13528
13529 if (size < (min = dstate->dtds_chunksize + sizeof (dtrace_dynhash_t)))
13530 size = min;
13531
13532 if ((base = kmem_zalloc(size, KM_NOSLEEP | KM_NORMALPRI)) == NULL)
13533 return (ENOMEM);
13534
13535 dstate->dtds_size = size;
13536 dstate->dtds_base = base;
13537 dstate->dtds_percpu = kmem_cache_alloc(dtrace_state_cache, KM_SLEEP);
13538 bzero(dstate->dtds_percpu, NCPU * sizeof (dtrace_dstate_percpu_t));
13539
13540 hashsize = size / (dstate->dtds_chunksize + sizeof (dtrace_dynhash_t));
13541
13542 if (hashsize != 1 && (hashsize & 1))
13543 hashsize--;
13544
13545 dstate->dtds_hashsize = hashsize;
13546 dstate->dtds_hash = dstate->dtds_base;
13547
13548 /*
13549 * Set all of our hash buckets to point to the single sink, and (if
13550 * it hasn't already been set), set the sink's hash value to be the
13551 * sink sentinel value. The sink is needed for dynamic variable
13552 * lookups to know that they have iterated over an entire, valid hash
13553 * chain.
13554 */
13555 for (i = 0; i < hashsize; i++)
13556 dstate->dtds_hash[i].dtdh_chain = &dtrace_dynhash_sink;
13557
13558 if (dtrace_dynhash_sink.dtdv_hashval != DTRACE_DYNHASH_SINK)
13559 dtrace_dynhash_sink.dtdv_hashval = DTRACE_DYNHASH_SINK;
13560
13561 /*
13562 * Determine number of active CPUs. Divide free list evenly among
13563 * active CPUs.
13564 */
13565 start = (dtrace_dynvar_t *)
13566 ((uintptr_t)base + hashsize * sizeof (dtrace_dynhash_t));
13567 limit = (uintptr_t)base + size;
13568
13569 VERIFY((uintptr_t)start < limit);
13570 VERIFY((uintptr_t)start >= (uintptr_t)base);
13571
13572 maxper = (limit - (uintptr_t)start) / NCPU;
13573 maxper = (maxper / dstate->dtds_chunksize) * dstate->dtds_chunksize;
13574
13575 for (i = 0; i < NCPU; i++) {
13576 dstate->dtds_percpu[i].dtdsc_free = dvar = start;
13577
13578 /*
13579 * If we don't even have enough chunks to make it once through
13580 * NCPUs, we're just going to allocate everything to the first
13581 * CPU. And if we're on the last CPU, we're going to allocate
13582 * whatever is left over. In either case, we set the limit to
13583 * be the limit of the dynamic variable space.
13584 */
13585 if (maxper == 0 || i == NCPU - 1) {
13586 limit = (uintptr_t)base + size;
13587 start = NULL;
13588 } else {
13589 limit = (uintptr_t)start + maxper;
13590 start = (dtrace_dynvar_t *)limit;
13591 }
13592
13593 VERIFY(limit <= (uintptr_t)base + size);
13594
13595 for (;;) {
13596 next = (dtrace_dynvar_t *)((uintptr_t)dvar +
13597 dstate->dtds_chunksize);
13598
13599 if ((uintptr_t)next + dstate->dtds_chunksize >= limit)
13600 break;
13601
13602 VERIFY((uintptr_t)dvar >= (uintptr_t)base &&
13603 (uintptr_t)dvar <= (uintptr_t)base + size);
13604 dvar->dtdv_next = next;
13605 dvar = next;
13606 }
13607
13608 if (maxper == 0)
13609 break;
13610 }
13611
13612 return (0);
13613 }
13614
13615 void
13616 dtrace_dstate_fini(dtrace_dstate_t *dstate)
13617 {
13618 ASSERT(MUTEX_HELD(&cpu_lock));
13619
13620 if (dstate->dtds_base == NULL)
13621 return;
13622
13623 kmem_free(dstate->dtds_base, dstate->dtds_size);
13624 kmem_cache_free(dtrace_state_cache, dstate->dtds_percpu);
13625 }
13626
13627 static void
13628 dtrace_vstate_fini(dtrace_vstate_t *vstate)
13629 {
13630 /*
13631 * Logical XOR, where are you?
13632 */
13633 ASSERT((vstate->dtvs_nglobals == 0) ^ (vstate->dtvs_globals != NULL));
13634
13635 if (vstate->dtvs_nglobals > 0) {
13636 kmem_free(vstate->dtvs_globals, vstate->dtvs_nglobals *
13637 sizeof (dtrace_statvar_t *));
13638 }
13639
13640 if (vstate->dtvs_ntlocals > 0) {
13641 kmem_free(vstate->dtvs_tlocals, vstate->dtvs_ntlocals *
13642 sizeof (dtrace_difv_t));
13643 }
13644
13645 ASSERT((vstate->dtvs_nlocals == 0) ^ (vstate->dtvs_locals != NULL));
13646
13647 if (vstate->dtvs_nlocals > 0) {
13648 kmem_free(vstate->dtvs_locals, vstate->dtvs_nlocals *
13649 sizeof (dtrace_statvar_t *));
13650 }
13651 }
13652
13653 static void
13654 dtrace_state_clean(dtrace_state_t *state)
13655 {
13656 if (state->dts_activity == DTRACE_ACTIVITY_INACTIVE)
13657 return;
13658
13659 dtrace_dynvar_clean(&state->dts_vstate.dtvs_dynvars);
13660 dtrace_speculation_clean(state);
13661 }
13662
13663 static void
13664 dtrace_state_deadman(dtrace_state_t *state)
13665 {
13666 hrtime_t now;
13667
13668 dtrace_sync();
13669
13670 now = dtrace_gethrtime();
13671
13672 if (state != dtrace_anon.dta_state &&
13673 now - state->dts_laststatus >= dtrace_deadman_user)
13674 return;
13675
13676 /*
13677 * We must be sure that dts_alive never appears to be less than the
13678 * value upon entry to dtrace_state_deadman(), and because we lack a
13679 * dtrace_cas64(), we cannot store to it atomically. We thus instead
13680 * store INT64_MAX to it, followed by a memory barrier, followed by
13681 * the new value. This assures that dts_alive never appears to be
13682 * less than its true value, regardless of the order in which the
13683 * stores to the underlying storage are issued.
13684 */
13685 state->dts_alive = INT64_MAX;
13686 dtrace_membar_producer();
13687 state->dts_alive = now;
13688 }
13689
13690 dtrace_state_t *
13691 dtrace_state_create(dev_t *devp, cred_t *cr)
13692 {
13693 minor_t minor;
13694 major_t major;
13695 char c[30];
13696 dtrace_state_t *state;
13697 dtrace_optval_t *opt;
13698 int bufsize = NCPU * sizeof (dtrace_buffer_t), i;
13699
13700 ASSERT(MUTEX_HELD(&dtrace_lock));
13701 ASSERT(MUTEX_HELD(&cpu_lock));
13702
13703 minor = (minor_t)(uintptr_t)vmem_alloc(dtrace_minor, 1,
13704 VM_BESTFIT | VM_SLEEP);
13705
13706 if (ddi_soft_state_zalloc(dtrace_softstate, minor) != DDI_SUCCESS) {
13707 vmem_free(dtrace_minor, (void *)(uintptr_t)minor, 1);
13708 return (NULL);
13709 }
13710
13711 state = ddi_get_soft_state(dtrace_softstate, minor);
13712 state->dts_epid = DTRACE_EPIDNONE + 1;
13713
13714 (void) snprintf(c, sizeof (c), "dtrace_aggid_%d", minor);
13715 state->dts_aggid_arena = vmem_create(c, (void *)1, UINT32_MAX, 1,
13716 NULL, NULL, NULL, 0, VM_SLEEP | VMC_IDENTIFIER);
13717
13718 if (devp != NULL) {
13719 major = getemajor(*devp);
13720 } else {
13721 major = ddi_driver_major(dtrace_devi);
13722 }
13723
13724 state->dts_dev = makedevice(major, minor);
13725
13726 if (devp != NULL)
13727 *devp = state->dts_dev;
13728
13729 /*
13730 * We allocate NCPU buffers. On the one hand, this can be quite
13731 * a bit of memory per instance (nearly 36K on a Starcat). On the
13732 * other hand, it saves an additional memory reference in the probe
13733 * path.
13734 */
13735 state->dts_buffer = kmem_zalloc(bufsize, KM_SLEEP);
13736 state->dts_aggbuffer = kmem_zalloc(bufsize, KM_SLEEP);
13737 state->dts_cleaner = CYCLIC_NONE;
13738 state->dts_deadman = CYCLIC_NONE;
13739 state->dts_vstate.dtvs_state = state;
13740
13741 for (i = 0; i < DTRACEOPT_MAX; i++)
13742 state->dts_options[i] = DTRACEOPT_UNSET;
13743
13744 /*
13745 * Set the default options.
13746 */
13747 opt = state->dts_options;
13748 opt[DTRACEOPT_BUFPOLICY] = DTRACEOPT_BUFPOLICY_SWITCH;
13749 opt[DTRACEOPT_BUFRESIZE] = DTRACEOPT_BUFRESIZE_AUTO;
13750 opt[DTRACEOPT_NSPEC] = dtrace_nspec_default;
13751 opt[DTRACEOPT_SPECSIZE] = dtrace_specsize_default;
13752 opt[DTRACEOPT_CPU] = (dtrace_optval_t)DTRACE_CPUALL;
13753 opt[DTRACEOPT_STRSIZE] = dtrace_strsize_default;
13754 opt[DTRACEOPT_STACKFRAMES] = dtrace_stackframes_default;
13755 opt[DTRACEOPT_USTACKFRAMES] = dtrace_ustackframes_default;
13756 opt[DTRACEOPT_CLEANRATE] = dtrace_cleanrate_default;
13757 opt[DTRACEOPT_AGGRATE] = dtrace_aggrate_default;
13758 opt[DTRACEOPT_SWITCHRATE] = dtrace_switchrate_default;
13759 opt[DTRACEOPT_STATUSRATE] = dtrace_statusrate_default;
13760 opt[DTRACEOPT_JSTACKFRAMES] = dtrace_jstackframes_default;
13761 opt[DTRACEOPT_JSTACKSTRSIZE] = dtrace_jstackstrsize_default;
13762
13763 state->dts_activity = DTRACE_ACTIVITY_INACTIVE;
13764
13765 /*
13766 * Depending on the user credentials, we set flag bits which alter probe
13767 * visibility or the amount of destructiveness allowed. In the case of
13768 * actual anonymous tracing, or the possession of all privileges, all of
13769 * the normal checks are bypassed.
13770 */
13771 if (cr == NULL || PRIV_POLICY_ONLY(cr, PRIV_ALL, B_FALSE)) {
13772 state->dts_cred.dcr_visible = DTRACE_CRV_ALL;
13773 state->dts_cred.dcr_action = DTRACE_CRA_ALL;
13774 } else {
13775 /*
13776 * Set up the credentials for this instantiation. We take a
13777 * hold on the credential to prevent it from disappearing on
13778 * us; this in turn prevents the zone_t referenced by this
13779 * credential from disappearing. This means that we can
13780 * examine the credential and the zone from probe context.
13781 */
13782 crhold(cr);
13783 state->dts_cred.dcr_cred = cr;
13784
13785 /*
13786 * CRA_PROC means "we have *some* privilege for dtrace" and
13787 * unlocks the use of variables like pid, zonename, etc.
13788 */
13789 if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_USER, B_FALSE) ||
13790 PRIV_POLICY_ONLY(cr, PRIV_DTRACE_PROC, B_FALSE)) {
13791 state->dts_cred.dcr_action |= DTRACE_CRA_PROC;
13792 }
13793
13794 /*
13795 * dtrace_user allows use of syscall and profile providers.
13796 * If the user also has proc_owner and/or proc_zone, we
13797 * extend the scope to include additional visibility and
13798 * destructive power.
13799 */
13800 if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_USER, B_FALSE)) {
13801 if (PRIV_POLICY_ONLY(cr, PRIV_PROC_OWNER, B_FALSE)) {
13802 state->dts_cred.dcr_visible |=
13803 DTRACE_CRV_ALLPROC;
13804
13805 state->dts_cred.dcr_action |=
13806 DTRACE_CRA_PROC_DESTRUCTIVE_ALLUSER;
13807 }
13808
13809 if (PRIV_POLICY_ONLY(cr, PRIV_PROC_ZONE, B_FALSE)) {
13810 state->dts_cred.dcr_visible |=
13811 DTRACE_CRV_ALLZONE;
13812
13813 state->dts_cred.dcr_action |=
13814 DTRACE_CRA_PROC_DESTRUCTIVE_ALLZONE;
13815 }
13816
13817 /*
13818 * If we have all privs in whatever zone this is,
13819 * we can do destructive things to processes which
13820 * have altered credentials.
13821 */
13822 if (priv_isequalset(priv_getset(cr, PRIV_EFFECTIVE),
13823 cr->cr_zone->zone_privset)) {
13824 state->dts_cred.dcr_action |=
13825 DTRACE_CRA_PROC_DESTRUCTIVE_CREDCHG;
13826 }
13827 }
13828
13829 /*
13830 * Holding the dtrace_kernel privilege also implies that
13831 * the user has the dtrace_user privilege from a visibility
13832 * perspective. But without further privileges, some
13833 * destructive actions are not available.
13834 */
13835 if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_KERNEL, B_FALSE)) {
13836 /*
13837 * Make all probes in all zones visible. However,
13838 * this doesn't mean that all actions become available
13839 * to all zones.
13840 */
13841 state->dts_cred.dcr_visible |= DTRACE_CRV_KERNEL |
13842 DTRACE_CRV_ALLPROC | DTRACE_CRV_ALLZONE;
13843
13844 state->dts_cred.dcr_action |= DTRACE_CRA_KERNEL |
13845 DTRACE_CRA_PROC;
13846 /*
13847 * Holding proc_owner means that destructive actions
13848 * for *this* zone are allowed.
13849 */
13850 if (PRIV_POLICY_ONLY(cr, PRIV_PROC_OWNER, B_FALSE))
13851 state->dts_cred.dcr_action |=
13852 DTRACE_CRA_PROC_DESTRUCTIVE_ALLUSER;
13853
13854 /*
13855 * Holding proc_zone means that destructive actions
13856 * for this user/group ID in all zones is allowed.
13857 */
13858 if (PRIV_POLICY_ONLY(cr, PRIV_PROC_ZONE, B_FALSE))
13859 state->dts_cred.dcr_action |=
13860 DTRACE_CRA_PROC_DESTRUCTIVE_ALLZONE;
13861
13862 /*
13863 * If we have all privs in whatever zone this is,
13864 * we can do destructive things to processes which
13865 * have altered credentials.
13866 */
13867 if (priv_isequalset(priv_getset(cr, PRIV_EFFECTIVE),
13868 cr->cr_zone->zone_privset)) {
13869 state->dts_cred.dcr_action |=
13870 DTRACE_CRA_PROC_DESTRUCTIVE_CREDCHG;
13871 }
13872 }
13873
13874 /*
13875 * Holding the dtrace_proc privilege gives control over fasttrap
13876 * and pid providers. We need to grant wider destructive
13877 * privileges in the event that the user has proc_owner and/or
13878 * proc_zone.
13879 */
13880 if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_PROC, B_FALSE)) {
13881 if (PRIV_POLICY_ONLY(cr, PRIV_PROC_OWNER, B_FALSE))
13882 state->dts_cred.dcr_action |=
13883 DTRACE_CRA_PROC_DESTRUCTIVE_ALLUSER;
13884
13885 if (PRIV_POLICY_ONLY(cr, PRIV_PROC_ZONE, B_FALSE))
13886 state->dts_cred.dcr_action |=
13887 DTRACE_CRA_PROC_DESTRUCTIVE_ALLZONE;
13888 }
13889 }
13890
13891 return (state);
13892 }
13893
13894 static int
13895 dtrace_state_buffer(dtrace_state_t *state, dtrace_buffer_t *buf, int which)
13896 {
13897 dtrace_optval_t *opt = state->dts_options, size;
13898 processorid_t cpu;
13899 int flags = 0, rval, factor, divisor = 1;
13900
13901 ASSERT(MUTEX_HELD(&dtrace_lock));
13902 ASSERT(MUTEX_HELD(&cpu_lock));
13903 ASSERT(which < DTRACEOPT_MAX);
13904 ASSERT(state->dts_activity == DTRACE_ACTIVITY_INACTIVE ||
13905 (state == dtrace_anon.dta_state &&
13906 state->dts_activity == DTRACE_ACTIVITY_ACTIVE));
13907
13908 if (opt[which] == DTRACEOPT_UNSET || opt[which] == 0)
13909 return (0);
13910
13911 if (opt[DTRACEOPT_CPU] != DTRACEOPT_UNSET)
13912 cpu = opt[DTRACEOPT_CPU];
13913
13914 if (which == DTRACEOPT_SPECSIZE)
13915 flags |= DTRACEBUF_NOSWITCH;
13916
13917 if (which == DTRACEOPT_BUFSIZE) {
13918 if (opt[DTRACEOPT_BUFPOLICY] == DTRACEOPT_BUFPOLICY_RING)
13919 flags |= DTRACEBUF_RING;
13920
13921 if (opt[DTRACEOPT_BUFPOLICY] == DTRACEOPT_BUFPOLICY_FILL)
13922 flags |= DTRACEBUF_FILL;
13923
13924 if (state != dtrace_anon.dta_state ||
13925 state->dts_activity != DTRACE_ACTIVITY_ACTIVE)
13926 flags |= DTRACEBUF_INACTIVE;
13927 }
13928
13929 for (size = opt[which]; size >= sizeof (uint64_t); size /= divisor) {
13930 /*
13931 * The size must be 8-byte aligned. If the size is not 8-byte
13932 * aligned, drop it down by the difference.
13933 */
13934 if (size & (sizeof (uint64_t) - 1))
13935 size -= size & (sizeof (uint64_t) - 1);
13936
13937 if (size < state->dts_reserve) {
13938 /*
13939 * Buffers always must be large enough to accommodate
13940 * their prereserved space. We return E2BIG instead
13941 * of ENOMEM in this case to allow for user-level
13942 * software to differentiate the cases.
13943 */
13944 return (E2BIG);
13945 }
13946
13947 rval = dtrace_buffer_alloc(buf, size, flags, cpu, &factor);
13948
13949 if (rval != ENOMEM) {
13950 opt[which] = size;
13951 return (rval);
13952 }
13953
13954 if (opt[DTRACEOPT_BUFRESIZE] == DTRACEOPT_BUFRESIZE_MANUAL)
13955 return (rval);
13956
13957 for (divisor = 2; divisor < factor; divisor <<= 1)
13958 continue;
13959 }
13960
13961 return (ENOMEM);
13962 }
13963
13964 static int
13965 dtrace_state_buffers(dtrace_state_t *state)
13966 {
13967 dtrace_speculation_t *spec = state->dts_speculations;
13968 int rval, i;
13969
13970 if ((rval = dtrace_state_buffer(state, state->dts_buffer,
13971 DTRACEOPT_BUFSIZE)) != 0)
13972 return (rval);
13973
13974 if ((rval = dtrace_state_buffer(state, state->dts_aggbuffer,
13975 DTRACEOPT_AGGSIZE)) != 0)
13976 return (rval);
13977
13978 for (i = 0; i < state->dts_nspeculations; i++) {
13979 if ((rval = dtrace_state_buffer(state,
13980 spec[i].dtsp_buffer, DTRACEOPT_SPECSIZE)) != 0)
13981 return (rval);
13982 }
13983
13984 return (0);
13985 }
13986
13987 static void
13988 dtrace_state_prereserve(dtrace_state_t *state)
13989 {
13990 dtrace_ecb_t *ecb;
13991 dtrace_probe_t *probe;
13992
13993 state->dts_reserve = 0;
13994
13995 if (state->dts_options[DTRACEOPT_BUFPOLICY] != DTRACEOPT_BUFPOLICY_FILL)
13996 return;
13997
13998 /*
13999 * If our buffer policy is a "fill" buffer policy, we need to set the
14000 * prereserved space to be the space required by the END probes.
14001 */
14002 probe = dtrace_probes[dtrace_probeid_end - 1];
14003 ASSERT(probe != NULL);
14004
14005 for (ecb = probe->dtpr_ecb; ecb != NULL; ecb = ecb->dte_next) {
14006 if (ecb->dte_state != state)
14007 continue;
14008
14009 state->dts_reserve += ecb->dte_needed + ecb->dte_alignment;
14010 }
14011 }
14012
14013 static int
14014 dtrace_state_go(dtrace_state_t *state, processorid_t *cpu)
14015 {
14016 dtrace_optval_t *opt = state->dts_options, sz, nspec;
14017 dtrace_speculation_t *spec;
14018 dtrace_buffer_t *buf;
14019 cyc_handler_t hdlr;
14020 cyc_time_t when;
14021 int rval = 0, i, bufsize = NCPU * sizeof (dtrace_buffer_t);
14022 dtrace_icookie_t cookie;
14023
14024 mutex_enter(&cpu_lock);
14025 mutex_enter(&dtrace_lock);
14026
14027 if (state->dts_activity != DTRACE_ACTIVITY_INACTIVE) {
14028 rval = EBUSY;
14029 goto out;
14030 }
14031
14032 /*
14033 * Before we can perform any checks, we must prime all of the
14034 * retained enablings that correspond to this state.
14035 */
14036 dtrace_enabling_prime(state);
14037
14038 if (state->dts_destructive && !state->dts_cred.dcr_destructive) {
14039 rval = EACCES;
14040 goto out;
14041 }
14042
14043 dtrace_state_prereserve(state);
14044
14045 /*
14046 * Now we want to do is try to allocate our speculations.
14047 * We do not automatically resize the number of speculations; if
14048 * this fails, we will fail the operation.
14049 */
14050 nspec = opt[DTRACEOPT_NSPEC];
14051 ASSERT(nspec != DTRACEOPT_UNSET);
14052
14053 if (nspec > INT_MAX) {
14054 rval = ENOMEM;
14055 goto out;
14056 }
14057
14058 spec = kmem_zalloc(nspec * sizeof (dtrace_speculation_t),
14059 KM_NOSLEEP | KM_NORMALPRI);
14060
14061 if (spec == NULL) {
14062 rval = ENOMEM;
14063 goto out;
14064 }
14065
14066 state->dts_speculations = spec;
14067 state->dts_nspeculations = (int)nspec;
14068
14069 for (i = 0; i < nspec; i++) {
14070 if ((buf = kmem_zalloc(bufsize,
14071 KM_NOSLEEP | KM_NORMALPRI)) == NULL) {
14072 rval = ENOMEM;
14073 goto err;
14074 }
14075
14076 spec[i].dtsp_buffer = buf;
14077 }
14078
14079 if (opt[DTRACEOPT_GRABANON] != DTRACEOPT_UNSET) {
14080 if (dtrace_anon.dta_state == NULL) {
14081 rval = ENOENT;
14082 goto out;
14083 }
14084
14085 if (state->dts_necbs != 0) {
14086 rval = EALREADY;
14087 goto out;
14088 }
14089
14090 state->dts_anon = dtrace_anon_grab();
14091 ASSERT(state->dts_anon != NULL);
14092 state = state->dts_anon;
14093
14094 /*
14095 * We want "grabanon" to be set in the grabbed state, so we'll
14096 * copy that option value from the grabbing state into the
14097 * grabbed state.
14098 */
14099 state->dts_options[DTRACEOPT_GRABANON] =
14100 opt[DTRACEOPT_GRABANON];
14101
14102 *cpu = dtrace_anon.dta_beganon;
14103
14104 /*
14105 * If the anonymous state is active (as it almost certainly
14106 * is if the anonymous enabling ultimately matched anything),
14107 * we don't allow any further option processing -- but we
14108 * don't return failure.
14109 */
14110 if (state->dts_activity != DTRACE_ACTIVITY_INACTIVE)
14111 goto out;
14112 }
14113
14114 if (opt[DTRACEOPT_AGGSIZE] != DTRACEOPT_UNSET &&
14115 opt[DTRACEOPT_AGGSIZE] != 0) {
14116 if (state->dts_aggregations == NULL) {
14117 /*
14118 * We're not going to create an aggregation buffer
14119 * because we don't have any ECBs that contain
14120 * aggregations -- set this option to 0.
14121 */
14122 opt[DTRACEOPT_AGGSIZE] = 0;
14123 } else {
14124 /*
14125 * If we have an aggregation buffer, we must also have
14126 * a buffer to use as scratch.
14127 */
14128 if (opt[DTRACEOPT_BUFSIZE] == DTRACEOPT_UNSET ||
14129 opt[DTRACEOPT_BUFSIZE] < state->dts_needed) {
14130 opt[DTRACEOPT_BUFSIZE] = state->dts_needed;
14131 }
14132 }
14133 }
14134
14135 if (opt[DTRACEOPT_SPECSIZE] != DTRACEOPT_UNSET &&
14136 opt[DTRACEOPT_SPECSIZE] != 0) {
14137 if (!state->dts_speculates) {
14138 /*
14139 * We're not going to create speculation buffers
14140 * because we don't have any ECBs that actually
14141 * speculate -- set the speculation size to 0.
14142 */
14143 opt[DTRACEOPT_SPECSIZE] = 0;
14144 }
14145 }
14146
14147 /*
14148 * The bare minimum size for any buffer that we're actually going to
14149 * do anything to is sizeof (uint64_t).
14150 */
14151 sz = sizeof (uint64_t);
14152
14153 if ((state->dts_needed != 0 && opt[DTRACEOPT_BUFSIZE] < sz) ||
14154 (state->dts_speculates && opt[DTRACEOPT_SPECSIZE] < sz) ||
14155 (state->dts_aggregations != NULL && opt[DTRACEOPT_AGGSIZE] < sz)) {
14156 /*
14157 * A buffer size has been explicitly set to 0 (or to a size
14158 * that will be adjusted to 0) and we need the space -- we
14159 * need to return failure. We return ENOSPC to differentiate
14160 * it from failing to allocate a buffer due to failure to meet
14161 * the reserve (for which we return E2BIG).
14162 */
14163 rval = ENOSPC;
14164 goto out;
14165 }
14166
14167 if ((rval = dtrace_state_buffers(state)) != 0)
14168 goto err;
14169
14170 if ((sz = opt[DTRACEOPT_DYNVARSIZE]) == DTRACEOPT_UNSET)
14171 sz = dtrace_dstate_defsize;
14172
14173 do {
14174 rval = dtrace_dstate_init(&state->dts_vstate.dtvs_dynvars, sz);
14175
14176 if (rval == 0)
14177 break;
14178
14179 if (opt[DTRACEOPT_BUFRESIZE] == DTRACEOPT_BUFRESIZE_MANUAL)
14180 goto err;
14181 } while (sz >>= 1);
14182
14183 opt[DTRACEOPT_DYNVARSIZE] = sz;
14184
14185 if (rval != 0)
14186 goto err;
14187
14188 if (opt[DTRACEOPT_STATUSRATE] > dtrace_statusrate_max)
14189 opt[DTRACEOPT_STATUSRATE] = dtrace_statusrate_max;
14190
14191 if (opt[DTRACEOPT_CLEANRATE] == 0)
14192 opt[DTRACEOPT_CLEANRATE] = dtrace_cleanrate_max;
14193
14194 if (opt[DTRACEOPT_CLEANRATE] < dtrace_cleanrate_min)
14195 opt[DTRACEOPT_CLEANRATE] = dtrace_cleanrate_min;
14196
14197 if (opt[DTRACEOPT_CLEANRATE] > dtrace_cleanrate_max)
14198 opt[DTRACEOPT_CLEANRATE] = dtrace_cleanrate_max;
14199
14200 hdlr.cyh_func = (cyc_func_t)dtrace_state_clean;
14201 hdlr.cyh_arg = state;
14202 hdlr.cyh_level = CY_LOW_LEVEL;
14203
14204 when.cyt_when = 0;
14205 when.cyt_interval = opt[DTRACEOPT_CLEANRATE];
14206
14207 state->dts_cleaner = cyclic_add(&hdlr, &when);
14208
14209 hdlr.cyh_func = (cyc_func_t)dtrace_state_deadman;
14210 hdlr.cyh_arg = state;
14211 hdlr.cyh_level = CY_LOW_LEVEL;
14212
14213 when.cyt_when = 0;
14214 when.cyt_interval = dtrace_deadman_interval;
14215
14216 state->dts_alive = state->dts_laststatus = dtrace_gethrtime();
14217 state->dts_deadman = cyclic_add(&hdlr, &when);
14218
14219 state->dts_activity = DTRACE_ACTIVITY_WARMUP;
14220
14221 if (state->dts_getf != 0 &&
14222 !(state->dts_cred.dcr_visible & DTRACE_CRV_KERNEL)) {
14223 /*
14224 * We don't have kernel privs but we have at least one call
14225 * to getf(); we need to bump our zone's count, and (if
14226 * this is the first enabling to have an unprivileged call
14227 * to getf()) we need to hook into closef().
14228 */
14229 state->dts_cred.dcr_cred->cr_zone->zone_dtrace_getf++;
14230
14231 if (dtrace_getf++ == 0) {
14232 ASSERT(dtrace_closef == NULL);
14233 dtrace_closef = dtrace_getf_barrier;
14234 }
14235 }
14236
14237 /*
14238 * Now it's time to actually fire the BEGIN probe. We need to disable
14239 * interrupts here both to record the CPU on which we fired the BEGIN
14240 * probe (the data from this CPU will be processed first at user
14241 * level) and to manually activate the buffer for this CPU.
14242 */
14243 cookie = dtrace_interrupt_disable();
14244 *cpu = CPU->cpu_id;
14245 ASSERT(state->dts_buffer[*cpu].dtb_flags & DTRACEBUF_INACTIVE);
14246 state->dts_buffer[*cpu].dtb_flags &= ~DTRACEBUF_INACTIVE;
14247
14248 dtrace_probe(dtrace_probeid_begin,
14249 (uint64_t)(uintptr_t)state, 0, 0, 0, 0);
14250 dtrace_interrupt_enable(cookie);
14251 /*
14252 * We may have had an exit action from a BEGIN probe; only change our
14253 * state to ACTIVE if we're still in WARMUP.
14254 */
14255 ASSERT(state->dts_activity == DTRACE_ACTIVITY_WARMUP ||
14256 state->dts_activity == DTRACE_ACTIVITY_DRAINING);
14257
14258 if (state->dts_activity == DTRACE_ACTIVITY_WARMUP)
14259 state->dts_activity = DTRACE_ACTIVITY_ACTIVE;
14260
14261 /*
14262 * Regardless of whether or not now we're in ACTIVE or DRAINING, we
14263 * want each CPU to transition its principal buffer out of the
14264 * INACTIVE state. Doing this assures that no CPU will suddenly begin
14265 * processing an ECB halfway down a probe's ECB chain; all CPUs will
14266 * atomically transition from processing none of a state's ECBs to
14267 * processing all of them.
14268 */
14269 dtrace_xcall(DTRACE_CPUALL,
14270 (dtrace_xcall_t)dtrace_buffer_activate, state);
14271 goto out;
14272
14273 err:
14274 dtrace_buffer_free(state->dts_buffer);
14275 dtrace_buffer_free(state->dts_aggbuffer);
14276
14277 if ((nspec = state->dts_nspeculations) == 0) {
14278 ASSERT(state->dts_speculations == NULL);
14279 goto out;
14280 }
14281
14282 spec = state->dts_speculations;
14283 ASSERT(spec != NULL);
14284
14285 for (i = 0; i < state->dts_nspeculations; i++) {
14286 if ((buf = spec[i].dtsp_buffer) == NULL)
14287 break;
14288
14289 dtrace_buffer_free(buf);
14290 kmem_free(buf, bufsize);
14291 }
14292
14293 kmem_free(spec, nspec * sizeof (dtrace_speculation_t));
14294 state->dts_nspeculations = 0;
14295 state->dts_speculations = NULL;
14296
14297 out:
14298 mutex_exit(&dtrace_lock);
14299 mutex_exit(&cpu_lock);
14300
14301 return (rval);
14302 }
14303
14304 static int
14305 dtrace_state_stop(dtrace_state_t *state, processorid_t *cpu)
14306 {
14307 dtrace_icookie_t cookie;
14308
14309 ASSERT(MUTEX_HELD(&dtrace_lock));
14310
14311 if (state->dts_activity != DTRACE_ACTIVITY_ACTIVE &&
14312 state->dts_activity != DTRACE_ACTIVITY_DRAINING)
14313 return (EINVAL);
14314
14315 /*
14316 * We'll set the activity to DTRACE_ACTIVITY_DRAINING, and issue a sync
14317 * to be sure that every CPU has seen it. See below for the details
14318 * on why this is done.
14319 */
14320 state->dts_activity = DTRACE_ACTIVITY_DRAINING;
14321 dtrace_sync();
14322
14323 /*
14324 * By this point, it is impossible for any CPU to be still processing
14325 * with DTRACE_ACTIVITY_ACTIVE. We can thus set our activity to
14326 * DTRACE_ACTIVITY_COOLDOWN and know that we're not racing with any
14327 * other CPU in dtrace_buffer_reserve(). This allows dtrace_probe()
14328 * and callees to know that the activity is DTRACE_ACTIVITY_COOLDOWN
14329 * iff we're in the END probe.
14330 */
14331 state->dts_activity = DTRACE_ACTIVITY_COOLDOWN;
14332 dtrace_sync();
14333 ASSERT(state->dts_activity == DTRACE_ACTIVITY_COOLDOWN);
14334
14335 /*
14336 * Finally, we can release the reserve and call the END probe. We
14337 * disable interrupts across calling the END probe to allow us to
14338 * return the CPU on which we actually called the END probe. This
14339 * allows user-land to be sure that this CPU's principal buffer is
14340 * processed last.
14341 */
14342 state->dts_reserve = 0;
14343
14344 cookie = dtrace_interrupt_disable();
14345 *cpu = CPU->cpu_id;
14346 dtrace_probe(dtrace_probeid_end,
14347 (uint64_t)(uintptr_t)state, 0, 0, 0, 0);
14348 dtrace_interrupt_enable(cookie);
14349
14350 state->dts_activity = DTRACE_ACTIVITY_STOPPED;
14351 dtrace_sync();
14352
14353 if (state->dts_getf != 0 &&
14354 !(state->dts_cred.dcr_visible & DTRACE_CRV_KERNEL)) {
14355 /*
14356 * We don't have kernel privs but we have at least one call
14357 * to getf(); we need to lower our zone's count, and (if
14358 * this is the last enabling to have an unprivileged call
14359 * to getf()) we need to clear the closef() hook.
14360 */
14361 ASSERT(state->dts_cred.dcr_cred->cr_zone->zone_dtrace_getf > 0);
14362 ASSERT(dtrace_closef == dtrace_getf_barrier);
14363 ASSERT(dtrace_getf > 0);
14364
14365 state->dts_cred.dcr_cred->cr_zone->zone_dtrace_getf--;
14366
14367 if (--dtrace_getf == 0)
14368 dtrace_closef = NULL;
14369 }
14370
14371 return (0);
14372 }
14373
14374 static int
14375 dtrace_state_option(dtrace_state_t *state, dtrace_optid_t option,
14376 dtrace_optval_t val)
14377 {
14378 ASSERT(MUTEX_HELD(&dtrace_lock));
14379
14380 if (state->dts_activity != DTRACE_ACTIVITY_INACTIVE)
14381 return (EBUSY);
14382
14383 if (option >= DTRACEOPT_MAX)
14384 return (EINVAL);
14385
14386 if (option != DTRACEOPT_CPU && val < 0)
14387 return (EINVAL);
14388
14389 switch (option) {
14390 case DTRACEOPT_DESTRUCTIVE:
14391 if (dtrace_destructive_disallow)
14392 return (EACCES);
14393
14394 state->dts_cred.dcr_destructive = 1;
14395 break;
14396
14397 case DTRACEOPT_BUFSIZE:
14398 case DTRACEOPT_DYNVARSIZE:
14399 case DTRACEOPT_AGGSIZE:
14400 case DTRACEOPT_SPECSIZE:
14401 case DTRACEOPT_STRSIZE:
14402 if (val < 0)
14403 return (EINVAL);
14404
14405 if (val >= LONG_MAX) {
14406 /*
14407 * If this is an otherwise negative value, set it to
14408 * the highest multiple of 128m less than LONG_MAX.
14409 * Technically, we're adjusting the size without
14410 * regard to the buffer resizing policy, but in fact,
14411 * this has no effect -- if we set the buffer size to
14412 * ~LONG_MAX and the buffer policy is ultimately set to
14413 * be "manual", the buffer allocation is guaranteed to
14414 * fail, if only because the allocation requires two
14415 * buffers. (We set the the size to the highest
14416 * multiple of 128m because it ensures that the size
14417 * will remain a multiple of a megabyte when
14418 * repeatedly halved -- all the way down to 15m.)
14419 */
14420 val = LONG_MAX - (1 << 27) + 1;
14421 }
14422 }
14423
14424 state->dts_options[option] = val;
14425
14426 return (0);
14427 }
14428
14429 static void
14430 dtrace_state_destroy(dtrace_state_t *state)
14431 {
14432 dtrace_ecb_t *ecb;
14433 dtrace_vstate_t *vstate = &state->dts_vstate;
14434 minor_t minor = getminor(state->dts_dev);
14435 int i, bufsize = NCPU * sizeof (dtrace_buffer_t);
14436 dtrace_speculation_t *spec = state->dts_speculations;
14437 int nspec = state->dts_nspeculations;
14438 uint32_t match;
14439
14440 ASSERT(MUTEX_HELD(&dtrace_lock));
14441 ASSERT(MUTEX_HELD(&cpu_lock));
14442
14443 /*
14444 * First, retract any retained enablings for this state.
14445 */
14446 dtrace_enabling_retract(state);
14447 ASSERT(state->dts_nretained == 0);
14448
14449 if (state->dts_activity == DTRACE_ACTIVITY_ACTIVE ||
14450 state->dts_activity == DTRACE_ACTIVITY_DRAINING) {
14451 /*
14452 * We have managed to come into dtrace_state_destroy() on a
14453 * hot enabling -- almost certainly because of a disorderly
14454 * shutdown of a consumer. (That is, a consumer that is
14455 * exiting without having called dtrace_stop().) In this case,
14456 * we're going to set our activity to be KILLED, and then
14457 * issue a sync to be sure that everyone is out of probe
14458 * context before we start blowing away ECBs.
14459 */
14460 state->dts_activity = DTRACE_ACTIVITY_KILLED;
14461 dtrace_sync();
14462 }
14463
14464 /*
14465 * Release the credential hold we took in dtrace_state_create().
14466 */
14467 if (state->dts_cred.dcr_cred != NULL)
14468 crfree(state->dts_cred.dcr_cred);
14469
14470 /*
14471 * Now we can safely disable and destroy any enabled probes. Because
14472 * any DTRACE_PRIV_KERNEL probes may actually be slowing our progress
14473 * (especially if they're all enabled), we take two passes through the
14474 * ECBs: in the first, we disable just DTRACE_PRIV_KERNEL probes, and
14475 * in the second we disable whatever is left over.
14476 */
14477 for (match = DTRACE_PRIV_KERNEL; ; match = 0) {
14478 for (i = 0; i < state->dts_necbs; i++) {
14479 if ((ecb = state->dts_ecbs[i]) == NULL)
14480 continue;
14481
14482 if (match && ecb->dte_probe != NULL) {
14483 dtrace_probe_t *probe = ecb->dte_probe;
14484 dtrace_provider_t *prov = probe->dtpr_provider;
14485
14486 if (!(prov->dtpv_priv.dtpp_flags & match))
14487 continue;
14488 }
14489
14490 dtrace_ecb_disable(ecb);
14491 dtrace_ecb_destroy(ecb);
14492 }
14493
14494 if (!match)
14495 break;
14496 }
14497
14498 /*
14499 * Before we free the buffers, perform one more sync to assure that
14500 * every CPU is out of probe context.
14501 */
14502 dtrace_sync();
14503
14504 dtrace_buffer_free(state->dts_buffer);
14505 dtrace_buffer_free(state->dts_aggbuffer);
14506
14507 for (i = 0; i < nspec; i++)
14508 dtrace_buffer_free(spec[i].dtsp_buffer);
14509
14510 if (state->dts_cleaner != CYCLIC_NONE)
14511 cyclic_remove(state->dts_cleaner);
14512
14513 if (state->dts_deadman != CYCLIC_NONE)
14514 cyclic_remove(state->dts_deadman);
14515
14516 dtrace_dstate_fini(&vstate->dtvs_dynvars);
14517 dtrace_vstate_fini(vstate);
14518 kmem_free(state->dts_ecbs, state->dts_necbs * sizeof (dtrace_ecb_t *));
14519
14520 if (state->dts_aggregations != NULL) {
14521 #ifdef DEBUG
14522 for (i = 0; i < state->dts_naggregations; i++)
14523 ASSERT(state->dts_aggregations[i] == NULL);
14524 #endif
14525 ASSERT(state->dts_naggregations > 0);
14526 kmem_free(state->dts_aggregations,
14527 state->dts_naggregations * sizeof (dtrace_aggregation_t *));
14528 }
14529
14530 kmem_free(state->dts_buffer, bufsize);
14531 kmem_free(state->dts_aggbuffer, bufsize);
14532
14533 for (i = 0; i < nspec; i++)
14534 kmem_free(spec[i].dtsp_buffer, bufsize);
14535
14536 kmem_free(spec, nspec * sizeof (dtrace_speculation_t));
14537
14538 dtrace_format_destroy(state);
14539
14540 vmem_destroy(state->dts_aggid_arena);
14541 ddi_soft_state_free(dtrace_softstate, minor);
14542 vmem_free(dtrace_minor, (void *)(uintptr_t)minor, 1);
14543 }
14544
14545 /*
14546 * DTrace Anonymous Enabling Functions
14547 */
14548 static dtrace_state_t *
14549 dtrace_anon_grab(void)
14550 {
14551 dtrace_state_t *state;
14552
14553 ASSERT(MUTEX_HELD(&dtrace_lock));
14554
14555 if ((state = dtrace_anon.dta_state) == NULL) {
14556 ASSERT(dtrace_anon.dta_enabling == NULL);
14557 return (NULL);
14558 }
14559
14560 ASSERT(dtrace_anon.dta_enabling != NULL);
14561 ASSERT(dtrace_retained != NULL);
14562
14563 dtrace_enabling_destroy(dtrace_anon.dta_enabling);
14564 dtrace_anon.dta_enabling = NULL;
14565 dtrace_anon.dta_state = NULL;
14566
14567 return (state);
14568 }
14569
14570 static void
14571 dtrace_anon_property(void)
14572 {
14573 int i, rv;
14574 dtrace_state_t *state;
14575 dof_hdr_t *dof;
14576 char c[32]; /* enough for "dof-data-" + digits */
14577
14578 ASSERT(MUTEX_HELD(&dtrace_lock));
14579 ASSERT(MUTEX_HELD(&cpu_lock));
14580
14581 for (i = 0; ; i++) {
14582 (void) snprintf(c, sizeof (c), "dof-data-%d", i);
14583
14584 dtrace_err_verbose = 1;
14585
14586 if ((dof = dtrace_dof_property(c)) == NULL) {
14587 dtrace_err_verbose = 0;
14588 break;
14589 }
14590
14591 /*
14592 * We want to create anonymous state, so we need to transition
14593 * the kernel debugger to indicate that DTrace is active. If
14594 * this fails (e.g. because the debugger has modified text in
14595 * some way), we won't continue with the processing.
14596 */
14597 if (kdi_dtrace_set(KDI_DTSET_DTRACE_ACTIVATE) != 0) {
14598 cmn_err(CE_NOTE, "kernel debugger active; anonymous "
14599 "enabling ignored.");
14600 dtrace_dof_destroy(dof);
14601 break;
14602 }
14603
14604 /*
14605 * If we haven't allocated an anonymous state, we'll do so now.
14606 */
14607 if ((state = dtrace_anon.dta_state) == NULL) {
14608 state = dtrace_state_create(NULL, NULL);
14609 dtrace_anon.dta_state = state;
14610
14611 if (state == NULL) {
14612 /*
14613 * This basically shouldn't happen: the only
14614 * failure mode from dtrace_state_create() is a
14615 * failure of ddi_soft_state_zalloc() that
14616 * itself should never happen. Still, the
14617 * interface allows for a failure mode, and
14618 * we want to fail as gracefully as possible:
14619 * we'll emit an error message and cease
14620 * processing anonymous state in this case.
14621 */
14622 cmn_err(CE_WARN, "failed to create "
14623 "anonymous state");
14624 dtrace_dof_destroy(dof);
14625 break;
14626 }
14627 }
14628
14629 rv = dtrace_dof_slurp(dof, &state->dts_vstate, CRED(),
14630 &dtrace_anon.dta_enabling, 0, B_TRUE);
14631
14632 if (rv == 0)
14633 rv = dtrace_dof_options(dof, state);
14634
14635 dtrace_err_verbose = 0;
14636 dtrace_dof_destroy(dof);
14637
14638 if (rv != 0) {
14639 /*
14640 * This is malformed DOF; chuck any anonymous state
14641 * that we created.
14642 */
14643 ASSERT(dtrace_anon.dta_enabling == NULL);
14644 dtrace_state_destroy(state);
14645 dtrace_anon.dta_state = NULL;
14646 break;
14647 }
14648
14649 ASSERT(dtrace_anon.dta_enabling != NULL);
14650 }
14651
14652 if (dtrace_anon.dta_enabling != NULL) {
14653 int rval;
14654
14655 /*
14656 * dtrace_enabling_retain() can only fail because we are
14657 * trying to retain more enablings than are allowed -- but
14658 * we only have one anonymous enabling, and we are guaranteed
14659 * to be allowed at least one retained enabling; we assert
14660 * that dtrace_enabling_retain() returns success.
14661 */
14662 rval = dtrace_enabling_retain(dtrace_anon.dta_enabling);
14663 ASSERT(rval == 0);
14664
14665 dtrace_enabling_dump(dtrace_anon.dta_enabling);
14666 }
14667 }
14668
14669 /*
14670 * DTrace Helper Functions
14671 */
14672 static void
14673 dtrace_helper_trace(dtrace_helper_action_t *helper,
14674 dtrace_mstate_t *mstate, dtrace_vstate_t *vstate, int where)
14675 {
14676 uint32_t size, next, nnext, i;
14677 dtrace_helptrace_t *ent, *buffer;
14678 uint16_t flags = cpu_core[CPU->cpu_id].cpuc_dtrace_flags;
14679
14680 if ((buffer = dtrace_helptrace_buffer) == NULL)
14681 return;
14682
14683 ASSERT(vstate->dtvs_nlocals <= dtrace_helptrace_nlocals);
14684
14685 /*
14686 * What would a tracing framework be without its own tracing
14687 * framework? (Well, a hell of a lot simpler, for starters...)
14688 */
14689 size = sizeof (dtrace_helptrace_t) + dtrace_helptrace_nlocals *
14690 sizeof (uint64_t) - sizeof (uint64_t);
14691
14692 /*
14693 * Iterate until we can allocate a slot in the trace buffer.
14694 */
14695 do {
14696 next = dtrace_helptrace_next;
14697
14698 if (next + size < dtrace_helptrace_bufsize) {
14699 nnext = next + size;
14700 } else {
14701 nnext = size;
14702 }
14703 } while (dtrace_cas32(&dtrace_helptrace_next, next, nnext) != next);
14704
14705 /*
14706 * We have our slot; fill it in.
14707 */
14708 if (nnext == size) {
14709 dtrace_helptrace_wrapped++;
14710 next = 0;
14711 }
14712
14713 ent = (dtrace_helptrace_t *)((uintptr_t)buffer + next);
14714 ent->dtht_helper = helper;
14715 ent->dtht_where = where;
14716 ent->dtht_nlocals = vstate->dtvs_nlocals;
14717
14718 ent->dtht_fltoffs = (mstate->dtms_present & DTRACE_MSTATE_FLTOFFS) ?
14719 mstate->dtms_fltoffs : -1;
14720 ent->dtht_fault = DTRACE_FLAGS2FLT(flags);
14721 ent->dtht_illval = cpu_core[CPU->cpu_id].cpuc_dtrace_illval;
14722
14723 for (i = 0; i < vstate->dtvs_nlocals; i++) {
14724 dtrace_statvar_t *svar;
14725
14726 if ((svar = vstate->dtvs_locals[i]) == NULL)
14727 continue;
14728
14729 ASSERT(svar->dtsv_size >= NCPU * sizeof (uint64_t));
14730 ent->dtht_locals[i] =
14731 ((uint64_t *)(uintptr_t)svar->dtsv_data)[CPU->cpu_id];
14732 }
14733 }
14734
14735 static uint64_t
14736 dtrace_helper(int which, dtrace_mstate_t *mstate,
14737 dtrace_state_t *state, uint64_t arg0, uint64_t arg1)
14738 {
14739 uint16_t *flags = &cpu_core[CPU->cpu_id].cpuc_dtrace_flags;
14740 uint64_t sarg0 = mstate->dtms_arg[0];
14741 uint64_t sarg1 = mstate->dtms_arg[1];
14742 uint64_t rval;
14743 dtrace_helpers_t *helpers = curproc->p_dtrace_helpers;
14744 dtrace_helper_action_t *helper;
14745 dtrace_vstate_t *vstate;
14746 dtrace_difo_t *pred;
14747 int i, trace = dtrace_helptrace_buffer != NULL;
14748
14749 ASSERT(which >= 0 && which < DTRACE_NHELPER_ACTIONS);
14750
14751 if (helpers == NULL)
14752 return (0);
14753
14754 if ((helper = helpers->dthps_actions[which]) == NULL)
14755 return (0);
14756
14757 vstate = &helpers->dthps_vstate;
14758 mstate->dtms_arg[0] = arg0;
14759 mstate->dtms_arg[1] = arg1;
14760
14761 /*
14762 * Now iterate over each helper. If its predicate evaluates to 'true',
14763 * we'll call the corresponding actions. Note that the below calls
14764 * to dtrace_dif_emulate() may set faults in machine state. This is
14765 * okay: our caller (the outer dtrace_dif_emulate()) will simply plow
14766 * the stored DIF offset with its own (which is the desired behavior).
14767 * Also, note the calls to dtrace_dif_emulate() may allocate scratch
14768 * from machine state; this is okay, too.
14769 */
14770 for (; helper != NULL; helper = helper->dtha_next) {
14771 if ((pred = helper->dtha_predicate) != NULL) {
14772 if (trace)
14773 dtrace_helper_trace(helper, mstate, vstate, 0);
14774
14775 if (!dtrace_dif_emulate(pred, mstate, vstate, state))
14776 goto next;
14777
14778 if (*flags & CPU_DTRACE_FAULT)
14779 goto err;
14780 }
14781
14782 for (i = 0; i < helper->dtha_nactions; i++) {
14783 if (trace)
14784 dtrace_helper_trace(helper,
14785 mstate, vstate, i + 1);
14786
14787 rval = dtrace_dif_emulate(helper->dtha_actions[i],
14788 mstate, vstate, state);
14789
14790 if (*flags & CPU_DTRACE_FAULT)
14791 goto err;
14792 }
14793
14794 next:
14795 if (trace)
14796 dtrace_helper_trace(helper, mstate, vstate,
14797 DTRACE_HELPTRACE_NEXT);
14798 }
14799
14800 if (trace)
14801 dtrace_helper_trace(helper, mstate, vstate,
14802 DTRACE_HELPTRACE_DONE);
14803
14804 /*
14805 * Restore the arg0 that we saved upon entry.
14806 */
14807 mstate->dtms_arg[0] = sarg0;
14808 mstate->dtms_arg[1] = sarg1;
14809
14810 return (rval);
14811
14812 err:
14813 if (trace)
14814 dtrace_helper_trace(helper, mstate, vstate,
14815 DTRACE_HELPTRACE_ERR);
14816
14817 /*
14818 * Restore the arg0 that we saved upon entry.
14819 */
14820 mstate->dtms_arg[0] = sarg0;
14821 mstate->dtms_arg[1] = sarg1;
14822
14823 return (NULL);
14824 }
14825
14826 static void
14827 dtrace_helper_action_destroy(dtrace_helper_action_t *helper,
14828 dtrace_vstate_t *vstate)
14829 {
14830 int i;
14831
14832 if (helper->dtha_predicate != NULL)
14833 dtrace_difo_release(helper->dtha_predicate, vstate);
14834
14835 for (i = 0; i < helper->dtha_nactions; i++) {
14836 ASSERT(helper->dtha_actions[i] != NULL);
14837 dtrace_difo_release(helper->dtha_actions[i], vstate);
14838 }
14839
14840 kmem_free(helper->dtha_actions,
14841 helper->dtha_nactions * sizeof (dtrace_difo_t *));
14842 kmem_free(helper, sizeof (dtrace_helper_action_t));
14843 }
14844
14845 static int
14846 dtrace_helper_destroygen(int gen)
14847 {
14848 proc_t *p = curproc;
14849 dtrace_helpers_t *help = p->p_dtrace_helpers;
14850 dtrace_vstate_t *vstate;
14851 int i;
14852
14853 ASSERT(MUTEX_HELD(&dtrace_lock));
14854
14855 if (help == NULL || gen > help->dthps_generation)
14856 return (EINVAL);
14857
14858 vstate = &help->dthps_vstate;
14859
14860 for (i = 0; i < DTRACE_NHELPER_ACTIONS; i++) {
14861 dtrace_helper_action_t *last = NULL, *h, *next;
14862
14863 for (h = help->dthps_actions[i]; h != NULL; h = next) {
14864 next = h->dtha_next;
14865
14866 if (h->dtha_generation == gen) {
14867 if (last != NULL) {
14868 last->dtha_next = next;
14869 } else {
14870 help->dthps_actions[i] = next;
14871 }
14872
14873 dtrace_helper_action_destroy(h, vstate);
14874 } else {
14875 last = h;
14876 }
14877 }
14878 }
14879
14880 /*
14881 * Interate until we've cleared out all helper providers with the
14882 * given generation number.
14883 */
14884 for (;;) {
14885 dtrace_helper_provider_t *prov;
14886
14887 /*
14888 * Look for a helper provider with the right generation. We
14889 * have to start back at the beginning of the list each time
14890 * because we drop dtrace_lock. It's unlikely that we'll make
14891 * more than two passes.
14892 */
14893 for (i = 0; i < help->dthps_nprovs; i++) {
14894 prov = help->dthps_provs[i];
14895
14896 if (prov->dthp_generation == gen)
14897 break;
14898 }
14899
14900 /*
14901 * If there were no matches, we're done.
14902 */
14903 if (i == help->dthps_nprovs)
14904 break;
14905
14906 /*
14907 * Move the last helper provider into this slot.
14908 */
14909 help->dthps_nprovs--;
14910 help->dthps_provs[i] = help->dthps_provs[help->dthps_nprovs];
14911 help->dthps_provs[help->dthps_nprovs] = NULL;
14912
14913 mutex_exit(&dtrace_lock);
14914
14915 /*
14916 * If we have a meta provider, remove this helper provider.
14917 */
14918 mutex_enter(&dtrace_meta_lock);
14919 if (dtrace_meta_pid != NULL) {
14920 ASSERT(dtrace_deferred_pid == NULL);
14921 dtrace_helper_provider_remove(&prov->dthp_prov,
14922 p->p_pid);
14923 }
14924 mutex_exit(&dtrace_meta_lock);
14925
14926 dtrace_helper_provider_destroy(prov);
14927
14928 mutex_enter(&dtrace_lock);
14929 }
14930
14931 return (0);
14932 }
14933
14934 static int
14935 dtrace_helper_validate(dtrace_helper_action_t *helper)
14936 {
14937 int err = 0, i;
14938 dtrace_difo_t *dp;
14939
14940 if ((dp = helper->dtha_predicate) != NULL)
14941 err += dtrace_difo_validate_helper(dp);
14942
14943 for (i = 0; i < helper->dtha_nactions; i++)
14944 err += dtrace_difo_validate_helper(helper->dtha_actions[i]);
14945
14946 return (err == 0);
14947 }
14948
14949 static int
14950 dtrace_helper_action_add(int which, dtrace_ecbdesc_t *ep)
14951 {
14952 dtrace_helpers_t *help;
14953 dtrace_helper_action_t *helper, *last;
14954 dtrace_actdesc_t *act;
14955 dtrace_vstate_t *vstate;
14956 dtrace_predicate_t *pred;
14957 int count = 0, nactions = 0, i;
14958
14959 if (which < 0 || which >= DTRACE_NHELPER_ACTIONS)
14960 return (EINVAL);
14961
14962 help = curproc->p_dtrace_helpers;
14963 last = help->dthps_actions[which];
14964 vstate = &help->dthps_vstate;
14965
14966 for (count = 0; last != NULL; last = last->dtha_next) {
14967 count++;
14968 if (last->dtha_next == NULL)
14969 break;
14970 }
14971
14972 /*
14973 * If we already have dtrace_helper_actions_max helper actions for this
14974 * helper action type, we'll refuse to add a new one.
14975 */
14976 if (count >= dtrace_helper_actions_max)
14977 return (ENOSPC);
14978
14979 helper = kmem_zalloc(sizeof (dtrace_helper_action_t), KM_SLEEP);
14980 helper->dtha_generation = help->dthps_generation;
14981
14982 if ((pred = ep->dted_pred.dtpdd_predicate) != NULL) {
14983 ASSERT(pred->dtp_difo != NULL);
14984 dtrace_difo_hold(pred->dtp_difo);
14985 helper->dtha_predicate = pred->dtp_difo;
14986 }
14987
14988 for (act = ep->dted_action; act != NULL; act = act->dtad_next) {
14989 if (act->dtad_kind != DTRACEACT_DIFEXPR)
14990 goto err;
14991
14992 if (act->dtad_difo == NULL)
14993 goto err;
14994
14995 nactions++;
14996 }
14997
14998 helper->dtha_actions = kmem_zalloc(sizeof (dtrace_difo_t *) *
14999 (helper->dtha_nactions = nactions), KM_SLEEP);
15000
15001 for (act = ep->dted_action, i = 0; act != NULL; act = act->dtad_next) {
15002 dtrace_difo_hold(act->dtad_difo);
15003 helper->dtha_actions[i++] = act->dtad_difo;
15004 }
15005
15006 if (!dtrace_helper_validate(helper))
15007 goto err;
15008
15009 if (last == NULL) {
15010 help->dthps_actions[which] = helper;
15011 } else {
15012 last->dtha_next = helper;
15013 }
15014
15015 if (vstate->dtvs_nlocals > dtrace_helptrace_nlocals) {
15016 dtrace_helptrace_nlocals = vstate->dtvs_nlocals;
15017 dtrace_helptrace_next = 0;
15018 }
15019
15020 return (0);
15021 err:
15022 dtrace_helper_action_destroy(helper, vstate);
15023 return (EINVAL);
15024 }
15025
15026 static void
15027 dtrace_helper_provider_register(proc_t *p, dtrace_helpers_t *help,
15028 dof_helper_t *dofhp)
15029 {
15030 ASSERT(MUTEX_NOT_HELD(&dtrace_lock));
15031
15032 mutex_enter(&dtrace_meta_lock);
15033 mutex_enter(&dtrace_lock);
15034
15035 if (!dtrace_attached() || dtrace_meta_pid == NULL) {
15036 /*
15037 * If the dtrace module is loaded but not attached, or if
15038 * there aren't isn't a meta provider registered to deal with
15039 * these provider descriptions, we need to postpone creating
15040 * the actual providers until later.
15041 */
15042
15043 if (help->dthps_next == NULL && help->dthps_prev == NULL &&
15044 dtrace_deferred_pid != help) {
15045 help->dthps_deferred = 1;
15046 help->dthps_pid = p->p_pid;
15047 help->dthps_next = dtrace_deferred_pid;
15048 help->dthps_prev = NULL;
15049 if (dtrace_deferred_pid != NULL)
15050 dtrace_deferred_pid->dthps_prev = help;
15051 dtrace_deferred_pid = help;
15052 }
15053
15054 mutex_exit(&dtrace_lock);
15055
15056 } else if (dofhp != NULL) {
15057 /*
15058 * If the dtrace module is loaded and we have a particular
15059 * helper provider description, pass that off to the
15060 * meta provider.
15061 */
15062
15063 mutex_exit(&dtrace_lock);
15064
15065 dtrace_helper_provide(dofhp, p->p_pid);
15066
15067 } else {
15068 /*
15069 * Otherwise, just pass all the helper provider descriptions
15070 * off to the meta provider.
15071 */
15072
15073 int i;
15074 mutex_exit(&dtrace_lock);
15075
15076 for (i = 0; i < help->dthps_nprovs; i++) {
15077 dtrace_helper_provide(&help->dthps_provs[i]->dthp_prov,
15078 p->p_pid);
15079 }
15080 }
15081
15082 mutex_exit(&dtrace_meta_lock);
15083 }
15084
15085 static int
15086 dtrace_helper_provider_add(dof_helper_t *dofhp, int gen)
15087 {
15088 dtrace_helpers_t *help;
15089 dtrace_helper_provider_t *hprov, **tmp_provs;
15090 uint_t tmp_maxprovs, i;
15091
15092 ASSERT(MUTEX_HELD(&dtrace_lock));
15093
15094 help = curproc->p_dtrace_helpers;
15095 ASSERT(help != NULL);
15096
15097 /*
15098 * If we already have dtrace_helper_providers_max helper providers,
15099 * we're refuse to add a new one.
15100 */
15101 if (help->dthps_nprovs >= dtrace_helper_providers_max)
15102 return (ENOSPC);
15103
15104 /*
15105 * Check to make sure this isn't a duplicate.
15106 */
15107 for (i = 0; i < help->dthps_nprovs; i++) {
15108 if (dofhp->dofhp_addr ==
15109 help->dthps_provs[i]->dthp_prov.dofhp_addr)
15110 return (EALREADY);
15111 }
15112
15113 hprov = kmem_zalloc(sizeof (dtrace_helper_provider_t), KM_SLEEP);
15114 hprov->dthp_prov = *dofhp;
15115 hprov->dthp_ref = 1;
15116 hprov->dthp_generation = gen;
15117
15118 /*
15119 * Allocate a bigger table for helper providers if it's already full.
15120 */
15121 if (help->dthps_maxprovs == help->dthps_nprovs) {
15122 tmp_maxprovs = help->dthps_maxprovs;
15123 tmp_provs = help->dthps_provs;
15124
15125 if (help->dthps_maxprovs == 0)
15126 help->dthps_maxprovs = 2;
15127 else
15128 help->dthps_maxprovs *= 2;
15129 if (help->dthps_maxprovs > dtrace_helper_providers_max)
15130 help->dthps_maxprovs = dtrace_helper_providers_max;
15131
15132 ASSERT(tmp_maxprovs < help->dthps_maxprovs);
15133
15134 help->dthps_provs = kmem_zalloc(help->dthps_maxprovs *
15135 sizeof (dtrace_helper_provider_t *), KM_SLEEP);
15136
15137 if (tmp_provs != NULL) {
15138 bcopy(tmp_provs, help->dthps_provs, tmp_maxprovs *
15139 sizeof (dtrace_helper_provider_t *));
15140 kmem_free(tmp_provs, tmp_maxprovs *
15141 sizeof (dtrace_helper_provider_t *));
15142 }
15143 }
15144
15145 help->dthps_provs[help->dthps_nprovs] = hprov;
15146 help->dthps_nprovs++;
15147
15148 return (0);
15149 }
15150
15151 static void
15152 dtrace_helper_provider_destroy(dtrace_helper_provider_t *hprov)
15153 {
15154 mutex_enter(&dtrace_lock);
15155
15156 if (--hprov->dthp_ref == 0) {
15157 dof_hdr_t *dof;
15158 mutex_exit(&dtrace_lock);
15159 dof = (dof_hdr_t *)(uintptr_t)hprov->dthp_prov.dofhp_dof;
15160 dtrace_dof_destroy(dof);
15161 kmem_free(hprov, sizeof (dtrace_helper_provider_t));
15162 } else {
15163 mutex_exit(&dtrace_lock);
15164 }
15165 }
15166
15167 static int
15168 dtrace_helper_provider_validate(dof_hdr_t *dof, dof_sec_t *sec)
15169 {
15170 uintptr_t daddr = (uintptr_t)dof;
15171 dof_sec_t *str_sec, *prb_sec, *arg_sec, *off_sec, *enoff_sec;
15172 dof_provider_t *provider;
15173 dof_probe_t *probe;
15174 uint8_t *arg;
15175 char *strtab, *typestr;
15176 dof_stridx_t typeidx;
15177 size_t typesz;
15178 uint_t nprobes, j, k;
15179
15180 ASSERT(sec->dofs_type == DOF_SECT_PROVIDER);
15181
15182 if (sec->dofs_offset & (sizeof (uint_t) - 1)) {
15183 dtrace_dof_error(dof, "misaligned section offset");
15184 return (-1);
15185 }
15186
15187 /*
15188 * The section needs to be large enough to contain the DOF provider
15189 * structure appropriate for the given version.
15190 */
15191 if (sec->dofs_size <
15192 ((dof->dofh_ident[DOF_ID_VERSION] == DOF_VERSION_1) ?
15193 offsetof(dof_provider_t, dofpv_prenoffs) :
15194 sizeof (dof_provider_t))) {
15195 dtrace_dof_error(dof, "provider section too small");
15196 return (-1);
15197 }
15198
15199 provider = (dof_provider_t *)(uintptr_t)(daddr + sec->dofs_offset);
15200 str_sec = dtrace_dof_sect(dof, DOF_SECT_STRTAB, provider->dofpv_strtab);
15201 prb_sec = dtrace_dof_sect(dof, DOF_SECT_PROBES, provider->dofpv_probes);
15202 arg_sec = dtrace_dof_sect(dof, DOF_SECT_PRARGS, provider->dofpv_prargs);
15203 off_sec = dtrace_dof_sect(dof, DOF_SECT_PROFFS, provider->dofpv_proffs);
15204
15205 if (str_sec == NULL || prb_sec == NULL ||
15206 arg_sec == NULL || off_sec == NULL)
15207 return (-1);
15208
15209 enoff_sec = NULL;
15210
15211 if (dof->dofh_ident[DOF_ID_VERSION] != DOF_VERSION_1 &&
15212 provider->dofpv_prenoffs != DOF_SECT_NONE &&
15213 (enoff_sec = dtrace_dof_sect(dof, DOF_SECT_PRENOFFS,
15214 provider->dofpv_prenoffs)) == NULL)
15215 return (-1);
15216
15217 strtab = (char *)(uintptr_t)(daddr + str_sec->dofs_offset);
15218
15219 if (provider->dofpv_name >= str_sec->dofs_size ||
15220 strlen(strtab + provider->dofpv_name) >= DTRACE_PROVNAMELEN) {
15221 dtrace_dof_error(dof, "invalid provider name");
15222 return (-1);
15223 }
15224
15225 if (prb_sec->dofs_entsize == 0 ||
15226 prb_sec->dofs_entsize > prb_sec->dofs_size) {
15227 dtrace_dof_error(dof, "invalid entry size");
15228 return (-1);
15229 }
15230
15231 if (prb_sec->dofs_entsize & (sizeof (uintptr_t) - 1)) {
15232 dtrace_dof_error(dof, "misaligned entry size");
15233 return (-1);
15234 }
15235
15236 if (off_sec->dofs_entsize != sizeof (uint32_t)) {
15237 dtrace_dof_error(dof, "invalid entry size");
15238 return (-1);
15239 }
15240
15241 if (off_sec->dofs_offset & (sizeof (uint32_t) - 1)) {
15242 dtrace_dof_error(dof, "misaligned section offset");
15243 return (-1);
15244 }
15245
15246 if (arg_sec->dofs_entsize != sizeof (uint8_t)) {
15247 dtrace_dof_error(dof, "invalid entry size");
15248 return (-1);
15249 }
15250
15251 arg = (uint8_t *)(uintptr_t)(daddr + arg_sec->dofs_offset);
15252
15253 nprobes = prb_sec->dofs_size / prb_sec->dofs_entsize;
15254
15255 /*
15256 * Take a pass through the probes to check for errors.
15257 */
15258 for (j = 0; j < nprobes; j++) {
15259 probe = (dof_probe_t *)(uintptr_t)(daddr +
15260 prb_sec->dofs_offset + j * prb_sec->dofs_entsize);
15261
15262 if (probe->dofpr_func >= str_sec->dofs_size) {
15263 dtrace_dof_error(dof, "invalid function name");
15264 return (-1);
15265 }
15266
15267 if (strlen(strtab + probe->dofpr_func) >= DTRACE_FUNCNAMELEN) {
15268 dtrace_dof_error(dof, "function name too long");
15269 return (-1);
15270 }
15271
15272 if (probe->dofpr_name >= str_sec->dofs_size ||
15273 strlen(strtab + probe->dofpr_name) >= DTRACE_NAMELEN) {
15274 dtrace_dof_error(dof, "invalid probe name");
15275 return (-1);
15276 }
15277
15278 /*
15279 * The offset count must not wrap the index, and the offsets
15280 * must also not overflow the section's data.
15281 */
15282 if (probe->dofpr_offidx + probe->dofpr_noffs <
15283 probe->dofpr_offidx ||
15284 (probe->dofpr_offidx + probe->dofpr_noffs) *
15285 off_sec->dofs_entsize > off_sec->dofs_size) {
15286 dtrace_dof_error(dof, "invalid probe offset");
15287 return (-1);
15288 }
15289
15290 if (dof->dofh_ident[DOF_ID_VERSION] != DOF_VERSION_1) {
15291 /*
15292 * If there's no is-enabled offset section, make sure
15293 * there aren't any is-enabled offsets. Otherwise
15294 * perform the same checks as for probe offsets
15295 * (immediately above).
15296 */
15297 if (enoff_sec == NULL) {
15298 if (probe->dofpr_enoffidx != 0 ||
15299 probe->dofpr_nenoffs != 0) {
15300 dtrace_dof_error(dof, "is-enabled "
15301 "offsets with null section");
15302 return (-1);
15303 }
15304 } else if (probe->dofpr_enoffidx +
15305 probe->dofpr_nenoffs < probe->dofpr_enoffidx ||
15306 (probe->dofpr_enoffidx + probe->dofpr_nenoffs) *
15307 enoff_sec->dofs_entsize > enoff_sec->dofs_size) {
15308 dtrace_dof_error(dof, "invalid is-enabled "
15309 "offset");
15310 return (-1);
15311 }
15312
15313 if (probe->dofpr_noffs + probe->dofpr_nenoffs == 0) {
15314 dtrace_dof_error(dof, "zero probe and "
15315 "is-enabled offsets");
15316 return (-1);
15317 }
15318 } else if (probe->dofpr_noffs == 0) {
15319 dtrace_dof_error(dof, "zero probe offsets");
15320 return (-1);
15321 }
15322
15323 if (probe->dofpr_argidx + probe->dofpr_xargc <
15324 probe->dofpr_argidx ||
15325 (probe->dofpr_argidx + probe->dofpr_xargc) *
15326 arg_sec->dofs_entsize > arg_sec->dofs_size) {
15327 dtrace_dof_error(dof, "invalid args");
15328 return (-1);
15329 }
15330
15331 typeidx = probe->dofpr_nargv;
15332 typestr = strtab + probe->dofpr_nargv;
15333 for (k = 0; k < probe->dofpr_nargc; k++) {
15334 if (typeidx >= str_sec->dofs_size) {
15335 dtrace_dof_error(dof, "bad "
15336 "native argument type");
15337 return (-1);
15338 }
15339
15340 typesz = strlen(typestr) + 1;
15341 if (typesz > DTRACE_ARGTYPELEN) {
15342 dtrace_dof_error(dof, "native "
15343 "argument type too long");
15344 return (-1);
15345 }
15346 typeidx += typesz;
15347 typestr += typesz;
15348 }
15349
15350 typeidx = probe->dofpr_xargv;
15351 typestr = strtab + probe->dofpr_xargv;
15352 for (k = 0; k < probe->dofpr_xargc; k++) {
15353 if (arg[probe->dofpr_argidx + k] > probe->dofpr_nargc) {
15354 dtrace_dof_error(dof, "bad "
15355 "native argument index");
15356 return (-1);
15357 }
15358
15359 if (typeidx >= str_sec->dofs_size) {
15360 dtrace_dof_error(dof, "bad "
15361 "translated argument type");
15362 return (-1);
15363 }
15364
15365 typesz = strlen(typestr) + 1;
15366 if (typesz > DTRACE_ARGTYPELEN) {
15367 dtrace_dof_error(dof, "translated argument "
15368 "type too long");
15369 return (-1);
15370 }
15371
15372 typeidx += typesz;
15373 typestr += typesz;
15374 }
15375 }
15376
15377 return (0);
15378 }
15379
15380 static int
15381 dtrace_helper_slurp(dof_hdr_t *dof, dof_helper_t *dhp)
15382 {
15383 dtrace_helpers_t *help;
15384 dtrace_vstate_t *vstate;
15385 dtrace_enabling_t *enab = NULL;
15386 int i, gen, rv, nhelpers = 0, nprovs = 0, destroy = 1;
15387 uintptr_t daddr = (uintptr_t)dof;
15388
15389 ASSERT(MUTEX_HELD(&dtrace_lock));
15390
15391 if ((help = curproc->p_dtrace_helpers) == NULL)
15392 help = dtrace_helpers_create(curproc);
15393
15394 vstate = &help->dthps_vstate;
15395
15396 if ((rv = dtrace_dof_slurp(dof, vstate, NULL, &enab,
15397 dhp != NULL ? dhp->dofhp_addr : 0, B_FALSE)) != 0) {
15398 dtrace_dof_destroy(dof);
15399 return (rv);
15400 }
15401
15402 /*
15403 * Look for helper providers and validate their descriptions.
15404 */
15405 if (dhp != NULL) {
15406 for (i = 0; i < dof->dofh_secnum; i++) {
15407 dof_sec_t *sec = (dof_sec_t *)(uintptr_t)(daddr +
15408 dof->dofh_secoff + i * dof->dofh_secsize);
15409
15410 if (sec->dofs_type != DOF_SECT_PROVIDER)
15411 continue;
15412
15413 if (dtrace_helper_provider_validate(dof, sec) != 0) {
15414 dtrace_enabling_destroy(enab);
15415 dtrace_dof_destroy(dof);
15416 return (-1);
15417 }
15418
15419 nprovs++;
15420 }
15421 }
15422
15423 /*
15424 * Now we need to walk through the ECB descriptions in the enabling.
15425 */
15426 for (i = 0; i < enab->dten_ndesc; i++) {
15427 dtrace_ecbdesc_t *ep = enab->dten_desc[i];
15428 dtrace_probedesc_t *desc = &ep->dted_probe;
15429
15430 if (strcmp(desc->dtpd_provider, "dtrace") != 0)
15431 continue;
15432
15433 if (strcmp(desc->dtpd_mod, "helper") != 0)
15434 continue;
15435
15436 if (strcmp(desc->dtpd_func, "ustack") != 0)
15437 continue;
15438
15439 if ((rv = dtrace_helper_action_add(DTRACE_HELPER_ACTION_USTACK,
15440 ep)) != 0) {
15441 /*
15442 * Adding this helper action failed -- we are now going
15443 * to rip out the entire generation and return failure.
15444 */
15445 (void) dtrace_helper_destroygen(help->dthps_generation);
15446 dtrace_enabling_destroy(enab);
15447 dtrace_dof_destroy(dof);
15448 return (-1);
15449 }
15450
15451 nhelpers++;
15452 }
15453
15454 if (nhelpers < enab->dten_ndesc)
15455 dtrace_dof_error(dof, "unmatched helpers");
15456
15457 gen = help->dthps_generation++;
15458 dtrace_enabling_destroy(enab);
15459
15460 if (dhp != NULL && nprovs > 0) {
15461 /*
15462 * Now that this is in-kernel, we change the sense of the
15463 * members: dofhp_dof denotes the in-kernel copy of the DOF
15464 * and dofhp_addr denotes the address at user-level.
15465 */
15466 dhp->dofhp_addr = dhp->dofhp_dof;
15467 dhp->dofhp_dof = (uint64_t)(uintptr_t)dof;
15468
15469 if (dtrace_helper_provider_add(dhp, gen) == 0) {
15470 mutex_exit(&dtrace_lock);
15471 dtrace_helper_provider_register(curproc, help, dhp);
15472 mutex_enter(&dtrace_lock);
15473
15474 destroy = 0;
15475 }
15476 }
15477
15478 if (destroy)
15479 dtrace_dof_destroy(dof);
15480
15481 return (gen);
15482 }
15483
15484 static dtrace_helpers_t *
15485 dtrace_helpers_create(proc_t *p)
15486 {
15487 dtrace_helpers_t *help;
15488
15489 ASSERT(MUTEX_HELD(&dtrace_lock));
15490 ASSERT(p->p_dtrace_helpers == NULL);
15491
15492 help = kmem_zalloc(sizeof (dtrace_helpers_t), KM_SLEEP);
15493 help->dthps_actions = kmem_zalloc(sizeof (dtrace_helper_action_t *) *
15494 DTRACE_NHELPER_ACTIONS, KM_SLEEP);
15495
15496 p->p_dtrace_helpers = help;
15497 dtrace_helpers++;
15498
15499 return (help);
15500 }
15501
15502 static void
15503 dtrace_helpers_destroy(proc_t *p)
15504 {
15505 dtrace_helpers_t *help;
15506 dtrace_vstate_t *vstate;
15507 int i;
15508
15509 mutex_enter(&dtrace_lock);
15510
15511 ASSERT(p->p_dtrace_helpers != NULL);
15512 ASSERT(dtrace_helpers > 0);
15513
15514 help = p->p_dtrace_helpers;
15515 vstate = &help->dthps_vstate;
15516
15517 /*
15518 * We're now going to lose the help from this process.
15519 */
15520 p->p_dtrace_helpers = NULL;
15521 if (p == curproc) {
15522 dtrace_sync();
15523 } else {
15524 /*
15525 * It is sometimes necessary to clean up dtrace helpers from a
15526 * an incomplete child process as part of a failed fork
15527 * operation. In such situations, a dtrace_sync() call should
15528 * be unnecessary as the process should be devoid of threads,
15529 * much less any in probe context.
15530 */
15531 VERIFY(p->p_stat == SIDL);
15532 }
15533
15534 /*
15535 * Destroy the helper actions.
15536 */
15537 for (i = 0; i < DTRACE_NHELPER_ACTIONS; i++) {
15538 dtrace_helper_action_t *h, *next;
15539
15540 for (h = help->dthps_actions[i]; h != NULL; h = next) {
15541 next = h->dtha_next;
15542 dtrace_helper_action_destroy(h, vstate);
15543 h = next;
15544 }
15545 }
15546
15547 mutex_exit(&dtrace_lock);
15548
15549 /*
15550 * Destroy the helper providers.
15551 */
15552 if (help->dthps_maxprovs > 0) {
15553 mutex_enter(&dtrace_meta_lock);
15554 if (dtrace_meta_pid != NULL) {
15555 ASSERT(dtrace_deferred_pid == NULL);
15556
15557 for (i = 0; i < help->dthps_nprovs; i++) {
15558 dtrace_helper_provider_remove(
15559 &help->dthps_provs[i]->dthp_prov, p->p_pid);
15560 }
15561 } else {
15562 mutex_enter(&dtrace_lock);
15563 ASSERT(help->dthps_deferred == 0 ||
15564 help->dthps_next != NULL ||
15565 help->dthps_prev != NULL ||
15566 help == dtrace_deferred_pid);
15567
15568 /*
15569 * Remove the helper from the deferred list.
15570 */
15571 if (help->dthps_next != NULL)
15572 help->dthps_next->dthps_prev = help->dthps_prev;
15573 if (help->dthps_prev != NULL)
15574 help->dthps_prev->dthps_next = help->dthps_next;
15575 if (dtrace_deferred_pid == help) {
15576 dtrace_deferred_pid = help->dthps_next;
15577 ASSERT(help->dthps_prev == NULL);
15578 }
15579
15580 mutex_exit(&dtrace_lock);
15581 }
15582
15583 mutex_exit(&dtrace_meta_lock);
15584
15585 for (i = 0; i < help->dthps_nprovs; i++) {
15586 dtrace_helper_provider_destroy(help->dthps_provs[i]);
15587 }
15588
15589 kmem_free(help->dthps_provs, help->dthps_maxprovs *
15590 sizeof (dtrace_helper_provider_t *));
15591 }
15592
15593 mutex_enter(&dtrace_lock);
15594
15595 dtrace_vstate_fini(&help->dthps_vstate);
15596 kmem_free(help->dthps_actions,
15597 sizeof (dtrace_helper_action_t *) * DTRACE_NHELPER_ACTIONS);
15598 kmem_free(help, sizeof (dtrace_helpers_t));
15599
15600 --dtrace_helpers;
15601 mutex_exit(&dtrace_lock);
15602 }
15603
15604 static void
15605 dtrace_helpers_duplicate(proc_t *from, proc_t *to)
15606 {
15607 dtrace_helpers_t *help, *newhelp;
15608 dtrace_helper_action_t *helper, *new, *last;
15609 dtrace_difo_t *dp;
15610 dtrace_vstate_t *vstate;
15611 int i, j, sz, hasprovs = 0;
15612
15613 mutex_enter(&dtrace_lock);
15614 ASSERT(from->p_dtrace_helpers != NULL);
15615 ASSERT(dtrace_helpers > 0);
15616
15617 help = from->p_dtrace_helpers;
15618 newhelp = dtrace_helpers_create(to);
15619 ASSERT(to->p_dtrace_helpers != NULL);
15620
15621 newhelp->dthps_generation = help->dthps_generation;
15622 vstate = &newhelp->dthps_vstate;
15623
15624 /*
15625 * Duplicate the helper actions.
15626 */
15627 for (i = 0; i < DTRACE_NHELPER_ACTIONS; i++) {
15628 if ((helper = help->dthps_actions[i]) == NULL)
15629 continue;
15630
15631 for (last = NULL; helper != NULL; helper = helper->dtha_next) {
15632 new = kmem_zalloc(sizeof (dtrace_helper_action_t),
15633 KM_SLEEP);
15634 new->dtha_generation = helper->dtha_generation;
15635
15636 if ((dp = helper->dtha_predicate) != NULL) {
15637 dp = dtrace_difo_duplicate(dp, vstate);
15638 new->dtha_predicate = dp;
15639 }
15640
15641 new->dtha_nactions = helper->dtha_nactions;
15642 sz = sizeof (dtrace_difo_t *) * new->dtha_nactions;
15643 new->dtha_actions = kmem_alloc(sz, KM_SLEEP);
15644
15645 for (j = 0; j < new->dtha_nactions; j++) {
15646 dtrace_difo_t *dp = helper->dtha_actions[j];
15647
15648 ASSERT(dp != NULL);
15649 dp = dtrace_difo_duplicate(dp, vstate);
15650 new->dtha_actions[j] = dp;
15651 }
15652
15653 if (last != NULL) {
15654 last->dtha_next = new;
15655 } else {
15656 newhelp->dthps_actions[i] = new;
15657 }
15658
15659 last = new;
15660 }
15661 }
15662
15663 /*
15664 * Duplicate the helper providers and register them with the
15665 * DTrace framework.
15666 */
15667 if (help->dthps_nprovs > 0) {
15668 newhelp->dthps_nprovs = help->dthps_nprovs;
15669 newhelp->dthps_maxprovs = help->dthps_nprovs;
15670 newhelp->dthps_provs = kmem_alloc(newhelp->dthps_nprovs *
15671 sizeof (dtrace_helper_provider_t *), KM_SLEEP);
15672 for (i = 0; i < newhelp->dthps_nprovs; i++) {
15673 newhelp->dthps_provs[i] = help->dthps_provs[i];
15674 newhelp->dthps_provs[i]->dthp_ref++;
15675 }
15676
15677 hasprovs = 1;
15678 }
15679
15680 mutex_exit(&dtrace_lock);
15681
15682 if (hasprovs)
15683 dtrace_helper_provider_register(to, newhelp, NULL);
15684 }
15685
15686 /*
15687 * DTrace Hook Functions
15688 */
15689 static void
15690 dtrace_module_loaded(struct modctl *ctl)
15691 {
15692 dtrace_provider_t *prv;
15693
15694 mutex_enter(&dtrace_provider_lock);
15695 mutex_enter(&mod_lock);
15696
15697 ASSERT(ctl->mod_busy);
15698
15699 /*
15700 * We're going to call each providers per-module provide operation
15701 * specifying only this module.
15702 */
15703 for (prv = dtrace_provider; prv != NULL; prv = prv->dtpv_next)
15704 prv->dtpv_pops.dtps_provide_module(prv->dtpv_arg, ctl);
15705
15706 mutex_exit(&mod_lock);
15707 mutex_exit(&dtrace_provider_lock);
15708
15709 /*
15710 * If we have any retained enablings, we need to match against them.
15711 * Enabling probes requires that cpu_lock be held, and we cannot hold
15712 * cpu_lock here -- it is legal for cpu_lock to be held when loading a
15713 * module. (In particular, this happens when loading scheduling
15714 * classes.) So if we have any retained enablings, we need to dispatch
15715 * our task queue to do the match for us.
15716 */
15717 mutex_enter(&dtrace_lock);
15718
15719 if (dtrace_retained == NULL) {
15720 mutex_exit(&dtrace_lock);
15721 return;
15722 }
15723
15724 (void) taskq_dispatch(dtrace_taskq,
15725 (task_func_t *)dtrace_enabling_matchall, NULL, TQ_SLEEP);
15726
15727 mutex_exit(&dtrace_lock);
15728
15729 /*
15730 * And now, for a little heuristic sleaze: in general, we want to
15731 * match modules as soon as they load. However, we cannot guarantee
15732 * this, because it would lead us to the lock ordering violation
15733 * outlined above. The common case, of course, is that cpu_lock is
15734 * _not_ held -- so we delay here for a clock tick, hoping that that's
15735 * long enough for the task queue to do its work. If it's not, it's
15736 * not a serious problem -- it just means that the module that we
15737 * just loaded may not be immediately instrumentable.
15738 */
15739 delay(1);
15740 }
15741
15742 static void
15743 dtrace_module_unloaded(struct modctl *ctl)
15744 {
15745 dtrace_probe_t template, *probe, *first, *next;
15746 dtrace_provider_t *prov;
15747
15748 template.dtpr_mod = ctl->mod_modname;
15749
15750 mutex_enter(&dtrace_provider_lock);
15751 mutex_enter(&mod_lock);
15752 mutex_enter(&dtrace_lock);
15753
15754 if (dtrace_bymod == NULL) {
15755 /*
15756 * The DTrace module is loaded (obviously) but not attached;
15757 * we don't have any work to do.
15758 */
15759 mutex_exit(&dtrace_provider_lock);
15760 mutex_exit(&mod_lock);
15761 mutex_exit(&dtrace_lock);
15762 return;
15763 }
15764
15765 for (probe = first = dtrace_hash_lookup(dtrace_bymod, &template);
15766 probe != NULL; probe = probe->dtpr_nextmod) {
15767 if (probe->dtpr_ecb != NULL) {
15768 mutex_exit(&dtrace_provider_lock);
15769 mutex_exit(&mod_lock);
15770 mutex_exit(&dtrace_lock);
15771
15772 /*
15773 * This shouldn't _actually_ be possible -- we're
15774 * unloading a module that has an enabled probe in it.
15775 * (It's normally up to the provider to make sure that
15776 * this can't happen.) However, because dtps_enable()
15777 * doesn't have a failure mode, there can be an
15778 * enable/unload race. Upshot: we don't want to
15779 * assert, but we're not going to disable the
15780 * probe, either.
15781 */
15782 if (dtrace_err_verbose) {
15783 cmn_err(CE_WARN, "unloaded module '%s' had "
15784 "enabled probes", ctl->mod_modname);
15785 }
15786
15787 return;
15788 }
15789 }
15790
15791 probe = first;
15792
15793 for (first = NULL; probe != NULL; probe = next) {
15794 ASSERT(dtrace_probes[probe->dtpr_id - 1] == probe);
15795
15796 dtrace_probes[probe->dtpr_id - 1] = NULL;
15797
15798 next = probe->dtpr_nextmod;
15799 dtrace_hash_remove(dtrace_bymod, probe);
15800 dtrace_hash_remove(dtrace_byfunc, probe);
15801 dtrace_hash_remove(dtrace_byname, probe);
15802
15803 if (first == NULL) {
15804 first = probe;
15805 probe->dtpr_nextmod = NULL;
15806 } else {
15807 probe->dtpr_nextmod = first;
15808 first = probe;
15809 }
15810 }
15811
15812 /*
15813 * We've removed all of the module's probes from the hash chains and
15814 * from the probe array. Now issue a dtrace_sync() to be sure that
15815 * everyone has cleared out from any probe array processing.
15816 */
15817 dtrace_sync();
15818
15819 for (probe = first; probe != NULL; probe = first) {
15820 first = probe->dtpr_nextmod;
15821 prov = probe->dtpr_provider;
15822 prov->dtpv_pops.dtps_destroy(prov->dtpv_arg, probe->dtpr_id,
15823 probe->dtpr_arg);
15824 kmem_free(probe->dtpr_mod, strlen(probe->dtpr_mod) + 1);
15825 kmem_free(probe->dtpr_func, strlen(probe->dtpr_func) + 1);
15826 kmem_free(probe->dtpr_name, strlen(probe->dtpr_name) + 1);
15827 vmem_free(dtrace_arena, (void *)(uintptr_t)probe->dtpr_id, 1);
15828 kmem_free(probe, sizeof (dtrace_probe_t));
15829 }
15830
15831 mutex_exit(&dtrace_lock);
15832 mutex_exit(&mod_lock);
15833 mutex_exit(&dtrace_provider_lock);
15834 }
15835
15836 void
15837 dtrace_suspend(void)
15838 {
15839 dtrace_probe_foreach(offsetof(dtrace_pops_t, dtps_suspend));
15840 }
15841
15842 void
15843 dtrace_resume(void)
15844 {
15845 dtrace_probe_foreach(offsetof(dtrace_pops_t, dtps_resume));
15846 }
15847
15848 static int
15849 dtrace_cpu_setup(cpu_setup_t what, processorid_t cpu)
15850 {
15851 ASSERT(MUTEX_HELD(&cpu_lock));
15852 mutex_enter(&dtrace_lock);
15853
15854 switch (what) {
15855 case CPU_CONFIG: {
15856 dtrace_state_t *state;
15857 dtrace_optval_t *opt, rs, c;
15858
15859 /*
15860 * For now, we only allocate a new buffer for anonymous state.
15861 */
15862 if ((state = dtrace_anon.dta_state) == NULL)
15863 break;
15864
15865 if (state->dts_activity != DTRACE_ACTIVITY_ACTIVE)
15866 break;
15867
15868 opt = state->dts_options;
15869 c = opt[DTRACEOPT_CPU];
15870
15871 if (c != DTRACE_CPUALL && c != DTRACEOPT_UNSET && c != cpu)
15872 break;
15873
15874 /*
15875 * Regardless of what the actual policy is, we're going to
15876 * temporarily set our resize policy to be manual. We're
15877 * also going to temporarily set our CPU option to denote
15878 * the newly configured CPU.
15879 */
15880 rs = opt[DTRACEOPT_BUFRESIZE];
15881 opt[DTRACEOPT_BUFRESIZE] = DTRACEOPT_BUFRESIZE_MANUAL;
15882 opt[DTRACEOPT_CPU] = (dtrace_optval_t)cpu;
15883
15884 (void) dtrace_state_buffers(state);
15885
15886 opt[DTRACEOPT_BUFRESIZE] = rs;
15887 opt[DTRACEOPT_CPU] = c;
15888
15889 break;
15890 }
15891
15892 case CPU_UNCONFIG:
15893 /*
15894 * We don't free the buffer in the CPU_UNCONFIG case. (The
15895 * buffer will be freed when the consumer exits.)
15896 */
15897 break;
15898
15899 default:
15900 break;
15901 }
15902
15903 mutex_exit(&dtrace_lock);
15904 return (0);
15905 }
15906
15907 static void
15908 dtrace_cpu_setup_initial(processorid_t cpu)
15909 {
15910 (void) dtrace_cpu_setup(CPU_CONFIG, cpu);
15911 }
15912
15913 static void
15914 dtrace_toxrange_add(uintptr_t base, uintptr_t limit)
15915 {
15916 if (dtrace_toxranges >= dtrace_toxranges_max) {
15917 int osize, nsize;
15918 dtrace_toxrange_t *range;
15919
15920 osize = dtrace_toxranges_max * sizeof (dtrace_toxrange_t);
15921
15922 if (osize == 0) {
15923 ASSERT(dtrace_toxrange == NULL);
15924 ASSERT(dtrace_toxranges_max == 0);
15925 dtrace_toxranges_max = 1;
15926 } else {
15927 dtrace_toxranges_max <<= 1;
15928 }
15929
15930 nsize = dtrace_toxranges_max * sizeof (dtrace_toxrange_t);
15931 range = kmem_zalloc(nsize, KM_SLEEP);
15932
15933 if (dtrace_toxrange != NULL) {
15934 ASSERT(osize != 0);
15935 bcopy(dtrace_toxrange, range, osize);
15936 kmem_free(dtrace_toxrange, osize);
15937 }
15938
15939 dtrace_toxrange = range;
15940 }
15941
15942 ASSERT(dtrace_toxrange[dtrace_toxranges].dtt_base == NULL);
15943 ASSERT(dtrace_toxrange[dtrace_toxranges].dtt_limit == NULL);
15944
15945 dtrace_toxrange[dtrace_toxranges].dtt_base = base;
15946 dtrace_toxrange[dtrace_toxranges].dtt_limit = limit;
15947 dtrace_toxranges++;
15948 }
15949
15950 static void
15951 dtrace_getf_barrier()
15952 {
15953 /*
15954 * When we have unprivileged (that is, non-DTRACE_CRV_KERNEL) enablings
15955 * that contain calls to getf(), this routine will be called on every
15956 * closef() before either the underlying vnode is released or the
15957 * file_t itself is freed. By the time we are here, it is essential
15958 * that the file_t can no longer be accessed from a call to getf()
15959 * in probe context -- that assures that a dtrace_sync() can be used
15960 * to clear out any enablings referring to the old structures.
15961 */
15962 if (curthread->t_procp->p_zone->zone_dtrace_getf != 0 ||
15963 kcred->cr_zone->zone_dtrace_getf != 0)
15964 dtrace_sync();
15965 }
15966
15967 /*
15968 * DTrace Driver Cookbook Functions
15969 */
15970 /*ARGSUSED*/
15971 static int
15972 dtrace_attach(dev_info_t *devi, ddi_attach_cmd_t cmd)
15973 {
15974 dtrace_provider_id_t id;
15975 dtrace_state_t *state = NULL;
15976 dtrace_enabling_t *enab;
15977
15978 mutex_enter(&cpu_lock);
15979 mutex_enter(&dtrace_provider_lock);
15980 mutex_enter(&dtrace_lock);
15981
15982 if (ddi_soft_state_init(&dtrace_softstate,
15983 sizeof (dtrace_state_t), 0) != 0) {
15984 cmn_err(CE_NOTE, "/dev/dtrace failed to initialize soft state");
15985 mutex_exit(&cpu_lock);
15986 mutex_exit(&dtrace_provider_lock);
15987 mutex_exit(&dtrace_lock);
15988 return (DDI_FAILURE);
15989 }
15990
15991 if (ddi_create_minor_node(devi, DTRACEMNR_DTRACE, S_IFCHR,
15992 DTRACEMNRN_DTRACE, DDI_PSEUDO, NULL) == DDI_FAILURE ||
15993 ddi_create_minor_node(devi, DTRACEMNR_HELPER, S_IFCHR,
15994 DTRACEMNRN_HELPER, DDI_PSEUDO, NULL) == DDI_FAILURE) {
15995 cmn_err(CE_NOTE, "/dev/dtrace couldn't create minor nodes");
15996 ddi_remove_minor_node(devi, NULL);
15997 ddi_soft_state_fini(&dtrace_softstate);
15998 mutex_exit(&cpu_lock);
15999 mutex_exit(&dtrace_provider_lock);
16000 mutex_exit(&dtrace_lock);
16001 return (DDI_FAILURE);
16002 }
16003
16004 ddi_report_dev(devi);
16005 dtrace_devi = devi;
16006
16007 dtrace_modload = dtrace_module_loaded;
16008 dtrace_modunload = dtrace_module_unloaded;
16009 dtrace_cpu_init = dtrace_cpu_setup_initial;
16010 dtrace_helpers_cleanup = dtrace_helpers_destroy;
16011 dtrace_helpers_fork = dtrace_helpers_duplicate;
16012 dtrace_cpustart_init = dtrace_suspend;
16013 dtrace_cpustart_fini = dtrace_resume;
16014 dtrace_debugger_init = dtrace_suspend;
16015 dtrace_debugger_fini = dtrace_resume;
16016
16017 register_cpu_setup_func((cpu_setup_func_t *)dtrace_cpu_setup, NULL);
16018
16019 ASSERT(MUTEX_HELD(&cpu_lock));
16020
16021 dtrace_arena = vmem_create("dtrace", (void *)1, UINT32_MAX, 1,
16022 NULL, NULL, NULL, 0, VM_SLEEP | VMC_IDENTIFIER);
16023 dtrace_minor = vmem_create("dtrace_minor", (void *)DTRACEMNRN_CLONE,
16024 UINT32_MAX - DTRACEMNRN_CLONE, 1, NULL, NULL, NULL, 0,
16025 VM_SLEEP | VMC_IDENTIFIER);
16026 dtrace_taskq = taskq_create("dtrace_taskq", 1, maxclsyspri,
16027 1, INT_MAX, 0);
16028
16029 dtrace_state_cache = kmem_cache_create("dtrace_state_cache",
16030 sizeof (dtrace_dstate_percpu_t) * NCPU, DTRACE_STATE_ALIGN,
16031 NULL, NULL, NULL, NULL, NULL, 0);
16032
16033 ASSERT(MUTEX_HELD(&cpu_lock));
16034 dtrace_bymod = dtrace_hash_create(offsetof(dtrace_probe_t, dtpr_mod),
16035 offsetof(dtrace_probe_t, dtpr_nextmod),
16036 offsetof(dtrace_probe_t, dtpr_prevmod));
16037
16038 dtrace_byfunc = dtrace_hash_create(offsetof(dtrace_probe_t, dtpr_func),
16039 offsetof(dtrace_probe_t, dtpr_nextfunc),
16040 offsetof(dtrace_probe_t, dtpr_prevfunc));
16041
16042 dtrace_byname = dtrace_hash_create(offsetof(dtrace_probe_t, dtpr_name),
16043 offsetof(dtrace_probe_t, dtpr_nextname),
16044 offsetof(dtrace_probe_t, dtpr_prevname));
16045
16046 if (dtrace_retain_max < 1) {
16047 cmn_err(CE_WARN, "illegal value (%lu) for dtrace_retain_max; "
16048 "setting to 1", dtrace_retain_max);
16049 dtrace_retain_max = 1;
16050 }
16051
16052 /*
16053 * Now discover our toxic ranges.
16054 */
16055 dtrace_toxic_ranges(dtrace_toxrange_add);
16056
16057 /*
16058 * Before we register ourselves as a provider to our own framework,
16059 * we would like to assert that dtrace_provider is NULL -- but that's
16060 * not true if we were loaded as a dependency of a DTrace provider.
16061 * Once we've registered, we can assert that dtrace_provider is our
16062 * pseudo provider.
16063 */
16064 (void) dtrace_register("dtrace", &dtrace_provider_attr,
16065 DTRACE_PRIV_NONE, 0, &dtrace_provider_ops, NULL, &id);
16066
16067 ASSERT(dtrace_provider != NULL);
16068 ASSERT((dtrace_provider_id_t)dtrace_provider == id);
16069
16070 dtrace_probeid_begin = dtrace_probe_create((dtrace_provider_id_t)
16071 dtrace_provider, NULL, NULL, "BEGIN", 0, NULL);
16072 dtrace_probeid_end = dtrace_probe_create((dtrace_provider_id_t)
16073 dtrace_provider, NULL, NULL, "END", 0, NULL);
16074 dtrace_probeid_error = dtrace_probe_create((dtrace_provider_id_t)
16075 dtrace_provider, NULL, NULL, "ERROR", 1, NULL);
16076
16077 dtrace_anon_property();
16078 mutex_exit(&cpu_lock);
16079
16080 /*
16081 * If there are already providers, we must ask them to provide their
16082 * probes, and then match any anonymous enabling against them. Note
16083 * that there should be no other retained enablings at this time:
16084 * the only retained enablings at this time should be the anonymous
16085 * enabling.
16086 */
16087 if (dtrace_anon.dta_enabling != NULL) {
16088 ASSERT(dtrace_retained == dtrace_anon.dta_enabling);
16089
16090 dtrace_enabling_provide(NULL);
16091 state = dtrace_anon.dta_state;
16092
16093 /*
16094 * We couldn't hold cpu_lock across the above call to
16095 * dtrace_enabling_provide(), but we must hold it to actually
16096 * enable the probes. We have to drop all of our locks, pick
16097 * up cpu_lock, and regain our locks before matching the
16098 * retained anonymous enabling.
16099 */
16100 mutex_exit(&dtrace_lock);
16101 mutex_exit(&dtrace_provider_lock);
16102
16103 mutex_enter(&cpu_lock);
16104 mutex_enter(&dtrace_provider_lock);
16105 mutex_enter(&dtrace_lock);
16106
16107 if ((enab = dtrace_anon.dta_enabling) != NULL)
16108 (void) dtrace_enabling_match(enab, NULL);
16109
16110 mutex_exit(&cpu_lock);
16111 }
16112
16113 mutex_exit(&dtrace_lock);
16114 mutex_exit(&dtrace_provider_lock);
16115
16116 if (state != NULL) {
16117 /*
16118 * If we created any anonymous state, set it going now.
16119 */
16120 (void) dtrace_state_go(state, &dtrace_anon.dta_beganon);
16121 }
16122
16123 return (DDI_SUCCESS);
16124 }
16125
16126 /*ARGSUSED*/
16127 static int
16128 dtrace_open(dev_t *devp, int flag, int otyp, cred_t *cred_p)
16129 {
16130 dtrace_state_t *state;
16131 uint32_t priv;
16132 uid_t uid;
16133 zoneid_t zoneid;
16134
16135 if (getminor(*devp) == DTRACEMNRN_HELPER)
16136 return (0);
16137
16138 /*
16139 * If this wasn't an open with the "helper" minor, then it must be
16140 * the "dtrace" minor.
16141 */
16142 if (getminor(*devp) != DTRACEMNRN_DTRACE)
16143 return (ENXIO);
16144
16145 /*
16146 * If no DTRACE_PRIV_* bits are set in the credential, then the
16147 * caller lacks sufficient permission to do anything with DTrace.
16148 */
16149 dtrace_cred2priv(cred_p, &priv, &uid, &zoneid);
16150 if (priv == DTRACE_PRIV_NONE)
16151 return (EACCES);
16152
16153 /*
16154 * Ask all providers to provide all their probes.
16155 */
16156 mutex_enter(&dtrace_provider_lock);
16157 dtrace_probe_provide(NULL, NULL);
16158 mutex_exit(&dtrace_provider_lock);
16159
16160 mutex_enter(&cpu_lock);
16161 mutex_enter(&dtrace_lock);
16162 dtrace_opens++;
16163 dtrace_membar_producer();
16164
16165 /*
16166 * If the kernel debugger is active (that is, if the kernel debugger
16167 * modified text in some way), we won't allow the open.
16168 */
16169 if (kdi_dtrace_set(KDI_DTSET_DTRACE_ACTIVATE) != 0) {
16170 dtrace_opens--;
16171 mutex_exit(&cpu_lock);
16172 mutex_exit(&dtrace_lock);
16173 return (EBUSY);
16174 }
16175
16176 if (dtrace_helptrace_enable && dtrace_helptrace_buffer == NULL) {
16177 /*
16178 * If DTrace helper tracing is enabled, we need to allocate the
16179 * trace buffer and initialize the values.
16180 */
16181 dtrace_helptrace_buffer =
16182 kmem_zalloc(dtrace_helptrace_bufsize, KM_SLEEP);
16183 dtrace_helptrace_next = 0;
16184 dtrace_helptrace_wrapped = 0;
16185 dtrace_helptrace_enable = 0;
16186 }
16187
16188 state = dtrace_state_create(devp, cred_p);
16189 mutex_exit(&cpu_lock);
16190
16191 if (state == NULL) {
16192 if (--dtrace_opens == 0 && dtrace_anon.dta_enabling == NULL)
16193 (void) kdi_dtrace_set(KDI_DTSET_DTRACE_DEACTIVATE);
16194 mutex_exit(&dtrace_lock);
16195 return (EAGAIN);
16196 }
16197
16198 mutex_exit(&dtrace_lock);
16199
16200 return (0);
16201 }
16202
16203 /*ARGSUSED*/
16204 static int
16205 dtrace_close(dev_t dev, int flag, int otyp, cred_t *cred_p)
16206 {
16207 minor_t minor = getminor(dev);
16208 dtrace_state_t *state;
16209 dtrace_helptrace_t *buf = NULL;
16210
16211 if (minor == DTRACEMNRN_HELPER)
16212 return (0);
16213
16214 state = ddi_get_soft_state(dtrace_softstate, minor);
16215
16216 mutex_enter(&cpu_lock);
16217 mutex_enter(&dtrace_lock);
16218
16219 if (state->dts_anon) {
16220 /*
16221 * There is anonymous state. Destroy that first.
16222 */
16223 ASSERT(dtrace_anon.dta_state == NULL);
16224 dtrace_state_destroy(state->dts_anon);
16225 }
16226
16227 if (dtrace_helptrace_disable) {
16228 /*
16229 * If we have been told to disable helper tracing, set the
16230 * buffer to NULL before calling into dtrace_state_destroy();
16231 * we take advantage of its dtrace_sync() to know that no
16232 * CPU is in probe context with enabled helper tracing
16233 * after it returns.
16234 */
16235 buf = dtrace_helptrace_buffer;
16236 dtrace_helptrace_buffer = NULL;
16237 }
16238
16239 dtrace_state_destroy(state);
16240 ASSERT(dtrace_opens > 0);
16241
16242 /*
16243 * Only relinquish control of the kernel debugger interface when there
16244 * are no consumers and no anonymous enablings.
16245 */
16246 if (--dtrace_opens == 0 && dtrace_anon.dta_enabling == NULL)
16247 (void) kdi_dtrace_set(KDI_DTSET_DTRACE_DEACTIVATE);
16248
16249 if (buf != NULL) {
16250 kmem_free(buf, dtrace_helptrace_bufsize);
16251 dtrace_helptrace_disable = 0;
16252 }
16253
16254 mutex_exit(&dtrace_lock);
16255 mutex_exit(&cpu_lock);
16256
16257 return (0);
16258 }
16259
16260 /*ARGSUSED*/
16261 static int
16262 dtrace_ioctl_helper(int cmd, intptr_t arg, int *rv)
16263 {
16264 int rval;
16265 dof_helper_t help, *dhp = NULL;
16266
16267 switch (cmd) {
16268 case DTRACEHIOC_ADDDOF:
16269 if (copyin((void *)arg, &help, sizeof (help)) != 0) {
16270 dtrace_dof_error(NULL, "failed to copyin DOF helper");
16271 return (EFAULT);
16272 }
16273
16274 dhp = &help;
16275 arg = (intptr_t)help.dofhp_dof;
16276 /*FALLTHROUGH*/
16277
16278 case DTRACEHIOC_ADD: {
16279 dof_hdr_t *dof = dtrace_dof_copyin(arg, &rval);
16280
16281 if (dof == NULL)
16282 return (rval);
16283
16284 mutex_enter(&dtrace_lock);
16285
16286 /*
16287 * dtrace_helper_slurp() takes responsibility for the dof --
16288 * it may free it now or it may save it and free it later.
16289 */
16290 if ((rval = dtrace_helper_slurp(dof, dhp)) != -1) {
16291 *rv = rval;
16292 rval = 0;
16293 } else {
16294 rval = EINVAL;
16295 }
16296
16297 mutex_exit(&dtrace_lock);
16298 return (rval);
16299 }
16300
16301 case DTRACEHIOC_REMOVE: {
16302 mutex_enter(&dtrace_lock);
16303 rval = dtrace_helper_destroygen(arg);
16304 mutex_exit(&dtrace_lock);
16305
16306 return (rval);
16307 }
16308
16309 default:
16310 break;
16311 }
16312
16313 return (ENOTTY);
16314 }
16315
16316 /*ARGSUSED*/
16317 static int
16318 dtrace_ioctl(dev_t dev, int cmd, intptr_t arg, int md, cred_t *cr, int *rv)
16319 {
16320 minor_t minor = getminor(dev);
16321 dtrace_state_t *state;
16322 int rval;
16323
16324 if (minor == DTRACEMNRN_HELPER)
16325 return (dtrace_ioctl_helper(cmd, arg, rv));
16326
16327 state = ddi_get_soft_state(dtrace_softstate, minor);
16328
16329 if (state->dts_anon) {
16330 ASSERT(dtrace_anon.dta_state == NULL);
16331 state = state->dts_anon;
16332 }
16333
16334 switch (cmd) {
16335 case DTRACEIOC_PROVIDER: {
16336 dtrace_providerdesc_t pvd;
16337 dtrace_provider_t *pvp;
16338
16339 if (copyin((void *)arg, &pvd, sizeof (pvd)) != 0)
16340 return (EFAULT);
16341
16342 pvd.dtvd_name[DTRACE_PROVNAMELEN - 1] = '\0';
16343 mutex_enter(&dtrace_provider_lock);
16344
16345 for (pvp = dtrace_provider; pvp != NULL; pvp = pvp->dtpv_next) {
16346 if (strcmp(pvp->dtpv_name, pvd.dtvd_name) == 0)
16347 break;
16348 }
16349
16350 mutex_exit(&dtrace_provider_lock);
16351
16352 if (pvp == NULL)
16353 return (ESRCH);
16354
16355 bcopy(&pvp->dtpv_priv, &pvd.dtvd_priv, sizeof (dtrace_ppriv_t));
16356 bcopy(&pvp->dtpv_attr, &pvd.dtvd_attr, sizeof (dtrace_pattr_t));
16357 if (copyout(&pvd, (void *)arg, sizeof (pvd)) != 0)
16358 return (EFAULT);
16359
16360 return (0);
16361 }
16362
16363 case DTRACEIOC_EPROBE: {
16364 dtrace_eprobedesc_t epdesc;
16365 dtrace_ecb_t *ecb;
16366 dtrace_action_t *act;
16367 void *buf;
16368 size_t size;
16369 uintptr_t dest;
16370 int nrecs;
16371
16372 if (copyin((void *)arg, &epdesc, sizeof (epdesc)) != 0)
16373 return (EFAULT);
16374
16375 mutex_enter(&dtrace_lock);
16376
16377 if ((ecb = dtrace_epid2ecb(state, epdesc.dtepd_epid)) == NULL) {
16378 mutex_exit(&dtrace_lock);
16379 return (EINVAL);
16380 }
16381
16382 if (ecb->dte_probe == NULL) {
16383 mutex_exit(&dtrace_lock);
16384 return (EINVAL);
16385 }
16386
16387 epdesc.dtepd_probeid = ecb->dte_probe->dtpr_id;
16388 epdesc.dtepd_uarg = ecb->dte_uarg;
16389 epdesc.dtepd_size = ecb->dte_size;
16390
16391 nrecs = epdesc.dtepd_nrecs;
16392 epdesc.dtepd_nrecs = 0;
16393 for (act = ecb->dte_action; act != NULL; act = act->dta_next) {
16394 if (DTRACEACT_ISAGG(act->dta_kind) || act->dta_intuple)
16395 continue;
16396
16397 epdesc.dtepd_nrecs++;
16398 }
16399
16400 /*
16401 * Now that we have the size, we need to allocate a temporary
16402 * buffer in which to store the complete description. We need
16403 * the temporary buffer to be able to drop dtrace_lock()
16404 * across the copyout(), below.
16405 */
16406 size = sizeof (dtrace_eprobedesc_t) +
16407 (epdesc.dtepd_nrecs * sizeof (dtrace_recdesc_t));
16408
16409 buf = kmem_alloc(size, KM_SLEEP);
16410 dest = (uintptr_t)buf;
16411
16412 bcopy(&epdesc, (void *)dest, sizeof (epdesc));
16413 dest += offsetof(dtrace_eprobedesc_t, dtepd_rec[0]);
16414
16415 for (act = ecb->dte_action; act != NULL; act = act->dta_next) {
16416 if (DTRACEACT_ISAGG(act->dta_kind) || act->dta_intuple)
16417 continue;
16418
16419 if (nrecs-- == 0)
16420 break;
16421
16422 bcopy(&act->dta_rec, (void *)dest,
16423 sizeof (dtrace_recdesc_t));
16424 dest += sizeof (dtrace_recdesc_t);
16425 }
16426
16427 mutex_exit(&dtrace_lock);
16428
16429 if (copyout(buf, (void *)arg, dest - (uintptr_t)buf) != 0) {
16430 kmem_free(buf, size);
16431 return (EFAULT);
16432 }
16433
16434 kmem_free(buf, size);
16435 return (0);
16436 }
16437
16438 case DTRACEIOC_AGGDESC: {
16439 dtrace_aggdesc_t aggdesc;
16440 dtrace_action_t *act;
16441 dtrace_aggregation_t *agg;
16442 int nrecs;
16443 uint32_t offs;
16444 dtrace_recdesc_t *lrec;
16445 void *buf;
16446 size_t size;
16447 uintptr_t dest;
16448
16449 if (copyin((void *)arg, &aggdesc, sizeof (aggdesc)) != 0)
16450 return (EFAULT);
16451
16452 mutex_enter(&dtrace_lock);
16453
16454 if ((agg = dtrace_aggid2agg(state, aggdesc.dtagd_id)) == NULL) {
16455 mutex_exit(&dtrace_lock);
16456 return (EINVAL);
16457 }
16458
16459 aggdesc.dtagd_epid = agg->dtag_ecb->dte_epid;
16460
16461 nrecs = aggdesc.dtagd_nrecs;
16462 aggdesc.dtagd_nrecs = 0;
16463
16464 offs = agg->dtag_base;
16465 lrec = &agg->dtag_action.dta_rec;
16466 aggdesc.dtagd_size = lrec->dtrd_offset + lrec->dtrd_size - offs;
16467
16468 for (act = agg->dtag_first; ; act = act->dta_next) {
16469 ASSERT(act->dta_intuple ||
16470 DTRACEACT_ISAGG(act->dta_kind));
16471
16472 /*
16473 * If this action has a record size of zero, it
16474 * denotes an argument to the aggregating action.
16475 * Because the presence of this record doesn't (or
16476 * shouldn't) affect the way the data is interpreted,
16477 * we don't copy it out to save user-level the
16478 * confusion of dealing with a zero-length record.
16479 */
16480 if (act->dta_rec.dtrd_size == 0) {
16481 ASSERT(agg->dtag_hasarg);
16482 continue;
16483 }
16484
16485 aggdesc.dtagd_nrecs++;
16486
16487 if (act == &agg->dtag_action)
16488 break;
16489 }
16490
16491 /*
16492 * Now that we have the size, we need to allocate a temporary
16493 * buffer in which to store the complete description. We need
16494 * the temporary buffer to be able to drop dtrace_lock()
16495 * across the copyout(), below.
16496 */
16497 size = sizeof (dtrace_aggdesc_t) +
16498 (aggdesc.dtagd_nrecs * sizeof (dtrace_recdesc_t));
16499
16500 buf = kmem_alloc(size, KM_SLEEP);
16501 dest = (uintptr_t)buf;
16502
16503 bcopy(&aggdesc, (void *)dest, sizeof (aggdesc));
16504 dest += offsetof(dtrace_aggdesc_t, dtagd_rec[0]);
16505
16506 for (act = agg->dtag_first; ; act = act->dta_next) {
16507 dtrace_recdesc_t rec = act->dta_rec;
16508
16509 /*
16510 * See the comment in the above loop for why we pass
16511 * over zero-length records.
16512 */
16513 if (rec.dtrd_size == 0) {
16514 ASSERT(agg->dtag_hasarg);
16515 continue;
16516 }
16517
16518 if (nrecs-- == 0)
16519 break;
16520
16521 rec.dtrd_offset -= offs;
16522 bcopy(&rec, (void *)dest, sizeof (rec));
16523 dest += sizeof (dtrace_recdesc_t);
16524
16525 if (act == &agg->dtag_action)
16526 break;
16527 }
16528
16529 mutex_exit(&dtrace_lock);
16530
16531 if (copyout(buf, (void *)arg, dest - (uintptr_t)buf) != 0) {
16532 kmem_free(buf, size);
16533 return (EFAULT);
16534 }
16535
16536 kmem_free(buf, size);
16537 return (0);
16538 }
16539
16540 case DTRACEIOC_ENABLE: {
16541 dof_hdr_t *dof;
16542 dtrace_enabling_t *enab = NULL;
16543 dtrace_vstate_t *vstate;
16544 int err = 0;
16545
16546 *rv = 0;
16547
16548 /*
16549 * If a NULL argument has been passed, we take this as our
16550 * cue to reevaluate our enablings.
16551 */
16552 if (arg == NULL) {
16553 dtrace_enabling_matchall();
16554
16555 return (0);
16556 }
16557
16558 if ((dof = dtrace_dof_copyin(arg, &rval)) == NULL)
16559 return (rval);
16560
16561 mutex_enter(&cpu_lock);
16562 mutex_enter(&dtrace_lock);
16563 vstate = &state->dts_vstate;
16564
16565 if (state->dts_activity != DTRACE_ACTIVITY_INACTIVE) {
16566 mutex_exit(&dtrace_lock);
16567 mutex_exit(&cpu_lock);
16568 dtrace_dof_destroy(dof);
16569 return (EBUSY);
16570 }
16571
16572 if (dtrace_dof_slurp(dof, vstate, cr, &enab, 0, B_TRUE) != 0) {
16573 mutex_exit(&dtrace_lock);
16574 mutex_exit(&cpu_lock);
16575 dtrace_dof_destroy(dof);
16576 return (EINVAL);
16577 }
16578
16579 if ((rval = dtrace_dof_options(dof, state)) != 0) {
16580 dtrace_enabling_destroy(enab);
16581 mutex_exit(&dtrace_lock);
16582 mutex_exit(&cpu_lock);
16583 dtrace_dof_destroy(dof);
16584 return (rval);
16585 }
16586
16587 if ((err = dtrace_enabling_match(enab, rv)) == 0) {
16588 err = dtrace_enabling_retain(enab);
16589 } else {
16590 dtrace_enabling_destroy(enab);
16591 }
16592
16593 mutex_exit(&cpu_lock);
16594 mutex_exit(&dtrace_lock);
16595 dtrace_dof_destroy(dof);
16596
16597 return (err);
16598 }
16599
16600 case DTRACEIOC_REPLICATE: {
16601 dtrace_repldesc_t desc;
16602 dtrace_probedesc_t *match = &desc.dtrpd_match;
16603 dtrace_probedesc_t *create = &desc.dtrpd_create;
16604 int err;
16605
16606 if (copyin((void *)arg, &desc, sizeof (desc)) != 0)
16607 return (EFAULT);
16608
16609 match->dtpd_provider[DTRACE_PROVNAMELEN - 1] = '\0';
16610 match->dtpd_mod[DTRACE_MODNAMELEN - 1] = '\0';
16611 match->dtpd_func[DTRACE_FUNCNAMELEN - 1] = '\0';
16612 match->dtpd_name[DTRACE_NAMELEN - 1] = '\0';
16613
16614 create->dtpd_provider[DTRACE_PROVNAMELEN - 1] = '\0';
16615 create->dtpd_mod[DTRACE_MODNAMELEN - 1] = '\0';
16616 create->dtpd_func[DTRACE_FUNCNAMELEN - 1] = '\0';
16617 create->dtpd_name[DTRACE_NAMELEN - 1] = '\0';
16618
16619 mutex_enter(&dtrace_lock);
16620 err = dtrace_enabling_replicate(state, match, create);
16621 mutex_exit(&dtrace_lock);
16622
16623 return (err);
16624 }
16625
16626 case DTRACEIOC_PROBEMATCH:
16627 case DTRACEIOC_PROBES: {
16628 dtrace_probe_t *probe = NULL;
16629 dtrace_probedesc_t desc;
16630 dtrace_probekey_t pkey;
16631 dtrace_id_t i;
16632 int m = 0;
16633 uint32_t priv;
16634 uid_t uid;
16635 zoneid_t zoneid;
16636
16637 if (copyin((void *)arg, &desc, sizeof (desc)) != 0)
16638 return (EFAULT);
16639
16640 desc.dtpd_provider[DTRACE_PROVNAMELEN - 1] = '\0';
16641 desc.dtpd_mod[DTRACE_MODNAMELEN - 1] = '\0';
16642 desc.dtpd_func[DTRACE_FUNCNAMELEN - 1] = '\0';
16643 desc.dtpd_name[DTRACE_NAMELEN - 1] = '\0';
16644
16645 /*
16646 * Before we attempt to match this probe, we want to give
16647 * all providers the opportunity to provide it.
16648 */
16649 if (desc.dtpd_id == DTRACE_IDNONE) {
16650 mutex_enter(&dtrace_provider_lock);
16651 dtrace_probe_provide(&desc, NULL);
16652 mutex_exit(&dtrace_provider_lock);
16653 desc.dtpd_id++;
16654 }
16655
16656 if (cmd == DTRACEIOC_PROBEMATCH) {
16657 dtrace_probekey(&desc, &pkey);
16658 pkey.dtpk_id = DTRACE_IDNONE;
16659 }
16660
16661 dtrace_cred2priv(cr, &priv, &uid, &zoneid);
16662
16663 mutex_enter(&dtrace_lock);
16664
16665 if (cmd == DTRACEIOC_PROBEMATCH) {
16666 for (i = desc.dtpd_id; i <= dtrace_nprobes; i++) {
16667 if ((probe = dtrace_probes[i - 1]) != NULL &&
16668 (m = dtrace_match_probe(probe, &pkey,
16669 priv, uid, zoneid)) != 0)
16670 break;
16671 }
16672
16673 if (m < 0) {
16674 mutex_exit(&dtrace_lock);
16675 return (EINVAL);
16676 }
16677
16678 } else {
16679 for (i = desc.dtpd_id; i <= dtrace_nprobes; i++) {
16680 if ((probe = dtrace_probes[i - 1]) != NULL &&
16681 dtrace_match_priv(probe, priv, uid, zoneid))
16682 break;
16683 }
16684 }
16685
16686 if (probe == NULL) {
16687 mutex_exit(&dtrace_lock);
16688 return (ESRCH);
16689 }
16690
16691 dtrace_probe_description(probe, &desc);
16692 mutex_exit(&dtrace_lock);
16693
16694 if (copyout(&desc, (void *)arg, sizeof (desc)) != 0)
16695 return (EFAULT);
16696
16697 return (0);
16698 }
16699
16700 case DTRACEIOC_PROBEARG: {
16701 dtrace_argdesc_t desc;
16702 dtrace_probe_t *probe;
16703 dtrace_provider_t *prov;
16704
16705 if (copyin((void *)arg, &desc, sizeof (desc)) != 0)
16706 return (EFAULT);
16707
16708 if (desc.dtargd_id == DTRACE_IDNONE)
16709 return (EINVAL);
16710
16711 if (desc.dtargd_ndx == DTRACE_ARGNONE)
16712 return (EINVAL);
16713
16714 mutex_enter(&dtrace_provider_lock);
16715 mutex_enter(&mod_lock);
16716 mutex_enter(&dtrace_lock);
16717
16718 if (desc.dtargd_id > dtrace_nprobes) {
16719 mutex_exit(&dtrace_lock);
16720 mutex_exit(&mod_lock);
16721 mutex_exit(&dtrace_provider_lock);
16722 return (EINVAL);
16723 }
16724
16725 if ((probe = dtrace_probes[desc.dtargd_id - 1]) == NULL) {
16726 mutex_exit(&dtrace_lock);
16727 mutex_exit(&mod_lock);
16728 mutex_exit(&dtrace_provider_lock);
16729 return (EINVAL);
16730 }
16731
16732 mutex_exit(&dtrace_lock);
16733
16734 prov = probe->dtpr_provider;
16735
16736 if (prov->dtpv_pops.dtps_getargdesc == NULL) {
16737 /*
16738 * There isn't any typed information for this probe.
16739 * Set the argument number to DTRACE_ARGNONE.
16740 */
16741 desc.dtargd_ndx = DTRACE_ARGNONE;
16742 } else {
16743 desc.dtargd_native[0] = '\0';
16744 desc.dtargd_xlate[0] = '\0';
16745 desc.dtargd_mapping = desc.dtargd_ndx;
16746
16747 prov->dtpv_pops.dtps_getargdesc(prov->dtpv_arg,
16748 probe->dtpr_id, probe->dtpr_arg, &desc);
16749 }
16750
16751 mutex_exit(&mod_lock);
16752 mutex_exit(&dtrace_provider_lock);
16753
16754 if (copyout(&desc, (void *)arg, sizeof (desc)) != 0)
16755 return (EFAULT);
16756
16757 return (0);
16758 }
16759
16760 case DTRACEIOC_GO: {
16761 processorid_t cpuid;
16762 rval = dtrace_state_go(state, &cpuid);
16763
16764 if (rval != 0)
16765 return (rval);
16766
16767 if (copyout(&cpuid, (void *)arg, sizeof (cpuid)) != 0)
16768 return (EFAULT);
16769
16770 return (0);
16771 }
16772
16773 case DTRACEIOC_STOP: {
16774 processorid_t cpuid;
16775
16776 mutex_enter(&dtrace_lock);
16777 rval = dtrace_state_stop(state, &cpuid);
16778 mutex_exit(&dtrace_lock);
16779
16780 if (rval != 0)
16781 return (rval);
16782
16783 if (copyout(&cpuid, (void *)arg, sizeof (cpuid)) != 0)
16784 return (EFAULT);
16785
16786 return (0);
16787 }
16788
16789 case DTRACEIOC_DOFGET: {
16790 dof_hdr_t hdr, *dof;
16791 uint64_t len;
16792
16793 if (copyin((void *)arg, &hdr, sizeof (hdr)) != 0)
16794 return (EFAULT);
16795
16796 mutex_enter(&dtrace_lock);
16797 dof = dtrace_dof_create(state);
16798 mutex_exit(&dtrace_lock);
16799
16800 len = MIN(hdr.dofh_loadsz, dof->dofh_loadsz);
16801 rval = copyout(dof, (void *)arg, len);
16802 dtrace_dof_destroy(dof);
16803
16804 return (rval == 0 ? 0 : EFAULT);
16805 }
16806
16807 case DTRACEIOC_AGGSNAP:
16808 case DTRACEIOC_BUFSNAP: {
16809 dtrace_bufdesc_t desc;
16810 caddr_t cached;
16811 dtrace_buffer_t *buf;
16812
16813 if (copyin((void *)arg, &desc, sizeof (desc)) != 0)
16814 return (EFAULT);
16815
16816 if (desc.dtbd_cpu < 0 || desc.dtbd_cpu >= NCPU)
16817 return (EINVAL);
16818
16819 mutex_enter(&dtrace_lock);
16820
16821 if (cmd == DTRACEIOC_BUFSNAP) {
16822 buf = &state->dts_buffer[desc.dtbd_cpu];
16823 } else {
16824 buf = &state->dts_aggbuffer[desc.dtbd_cpu];
16825 }
16826
16827 if (buf->dtb_flags & (DTRACEBUF_RING | DTRACEBUF_FILL)) {
16828 size_t sz = buf->dtb_offset;
16829
16830 if (state->dts_activity != DTRACE_ACTIVITY_STOPPED) {
16831 mutex_exit(&dtrace_lock);
16832 return (EBUSY);
16833 }
16834
16835 /*
16836 * If this buffer has already been consumed, we're
16837 * going to indicate that there's nothing left here
16838 * to consume.
16839 */
16840 if (buf->dtb_flags & DTRACEBUF_CONSUMED) {
16841 mutex_exit(&dtrace_lock);
16842
16843 desc.dtbd_size = 0;
16844 desc.dtbd_drops = 0;
16845 desc.dtbd_errors = 0;
16846 desc.dtbd_oldest = 0;
16847 sz = sizeof (desc);
16848
16849 if (copyout(&desc, (void *)arg, sz) != 0)
16850 return (EFAULT);
16851
16852 return (0);
16853 }
16854
16855 /*
16856 * If this is a ring buffer that has wrapped, we want
16857 * to copy the whole thing out.
16858 */
16859 if (buf->dtb_flags & DTRACEBUF_WRAPPED) {
16860 dtrace_buffer_polish(buf);
16861 sz = buf->dtb_size;
16862 }
16863
16864 if (copyout(buf->dtb_tomax, desc.dtbd_data, sz) != 0) {
16865 mutex_exit(&dtrace_lock);
16866 return (EFAULT);
16867 }
16868
16869 desc.dtbd_size = sz;
16870 desc.dtbd_drops = buf->dtb_drops;
16871 desc.dtbd_errors = buf->dtb_errors;
16872 desc.dtbd_oldest = buf->dtb_xamot_offset;
16873 desc.dtbd_timestamp = dtrace_gethrtime();
16874
16875 mutex_exit(&dtrace_lock);
16876
16877 if (copyout(&desc, (void *)arg, sizeof (desc)) != 0)
16878 return (EFAULT);
16879
16880 buf->dtb_flags |= DTRACEBUF_CONSUMED;
16881
16882 return (0);
16883 }
16884
16885 if (buf->dtb_tomax == NULL) {
16886 ASSERT(buf->dtb_xamot == NULL);
16887 mutex_exit(&dtrace_lock);
16888 return (ENOENT);
16889 }
16890
16891 cached = buf->dtb_tomax;
16892 ASSERT(!(buf->dtb_flags & DTRACEBUF_NOSWITCH));
16893
16894 dtrace_xcall(desc.dtbd_cpu,
16895 (dtrace_xcall_t)dtrace_buffer_switch, buf);
16896
16897 state->dts_errors += buf->dtb_xamot_errors;
16898
16899 /*
16900 * If the buffers did not actually switch, then the cross call
16901 * did not take place -- presumably because the given CPU is
16902 * not in the ready set. If this is the case, we'll return
16903 * ENOENT.
16904 */
16905 if (buf->dtb_tomax == cached) {
16906 ASSERT(buf->dtb_xamot != cached);
16907 mutex_exit(&dtrace_lock);
16908 return (ENOENT);
16909 }
16910
16911 ASSERT(cached == buf->dtb_xamot);
16912
16913 /*
16914 * We have our snapshot; now copy it out.
16915 */
16916 if (copyout(buf->dtb_xamot, desc.dtbd_data,
16917 buf->dtb_xamot_offset) != 0) {
16918 mutex_exit(&dtrace_lock);
16919 return (EFAULT);
16920 }
16921
16922 desc.dtbd_size = buf->dtb_xamot_offset;
16923 desc.dtbd_drops = buf->dtb_xamot_drops;
16924 desc.dtbd_errors = buf->dtb_xamot_errors;
16925 desc.dtbd_oldest = 0;
16926 desc.dtbd_timestamp = buf->dtb_switched;
16927
16928 mutex_exit(&dtrace_lock);
16929
16930 /*
16931 * Finally, copy out the buffer description.
16932 */
16933 if (copyout(&desc, (void *)arg, sizeof (desc)) != 0)
16934 return (EFAULT);
16935
16936 return (0);
16937 }
16938
16939 case DTRACEIOC_CONF: {
16940 dtrace_conf_t conf;
16941
16942 bzero(&conf, sizeof (conf));
16943 conf.dtc_difversion = DIF_VERSION;
16944 conf.dtc_difintregs = DIF_DIR_NREGS;
16945 conf.dtc_diftupregs = DIF_DTR_NREGS;
16946 conf.dtc_ctfmodel = CTF_MODEL_NATIVE;
16947
16948 if (copyout(&conf, (void *)arg, sizeof (conf)) != 0)
16949 return (EFAULT);
16950
16951 return (0);
16952 }
16953
16954 case DTRACEIOC_STATUS: {
16955 dtrace_status_t stat;
16956 dtrace_dstate_t *dstate;
16957 int i, j;
16958 uint64_t nerrs;
16959
16960 /*
16961 * See the comment in dtrace_state_deadman() for the reason
16962 * for setting dts_laststatus to INT64_MAX before setting
16963 * it to the correct value.
16964 */
16965 state->dts_laststatus = INT64_MAX;
16966 dtrace_membar_producer();
16967 state->dts_laststatus = dtrace_gethrtime();
16968
16969 bzero(&stat, sizeof (stat));
16970
16971 mutex_enter(&dtrace_lock);
16972
16973 if (state->dts_activity == DTRACE_ACTIVITY_INACTIVE) {
16974 mutex_exit(&dtrace_lock);
16975 return (ENOENT);
16976 }
16977
16978 if (state->dts_activity == DTRACE_ACTIVITY_DRAINING)
16979 stat.dtst_exiting = 1;
16980
16981 nerrs = state->dts_errors;
16982 dstate = &state->dts_vstate.dtvs_dynvars;
16983
16984 for (i = 0; i < NCPU; i++) {
16985 dtrace_dstate_percpu_t *dcpu = &dstate->dtds_percpu[i];
16986
16987 stat.dtst_dyndrops += dcpu->dtdsc_drops;
16988 stat.dtst_dyndrops_dirty += dcpu->dtdsc_dirty_drops;
16989 stat.dtst_dyndrops_rinsing += dcpu->dtdsc_rinsing_drops;
16990
16991 if (state->dts_buffer[i].dtb_flags & DTRACEBUF_FULL)
16992 stat.dtst_filled++;
16993
16994 nerrs += state->dts_buffer[i].dtb_errors;
16995
16996 for (j = 0; j < state->dts_nspeculations; j++) {
16997 dtrace_speculation_t *spec;
16998 dtrace_buffer_t *buf;
16999
17000 spec = &state->dts_speculations[j];
17001 buf = &spec->dtsp_buffer[i];
17002 stat.dtst_specdrops += buf->dtb_xamot_drops;
17003 }
17004 }
17005
17006 stat.dtst_specdrops_busy = state->dts_speculations_busy;
17007 stat.dtst_specdrops_unavail = state->dts_speculations_unavail;
17008 stat.dtst_stkstroverflows = state->dts_stkstroverflows;
17009 stat.dtst_dblerrors = state->dts_dblerrors;
17010 stat.dtst_killed =
17011 (state->dts_activity == DTRACE_ACTIVITY_KILLED);
17012 stat.dtst_errors = nerrs;
17013
17014 mutex_exit(&dtrace_lock);
17015
17016 if (copyout(&stat, (void *)arg, sizeof (stat)) != 0)
17017 return (EFAULT);
17018
17019 return (0);
17020 }
17021
17022 case DTRACEIOC_FORMAT: {
17023 dtrace_fmtdesc_t fmt;
17024 char *str;
17025 int len;
17026
17027 if (copyin((void *)arg, &fmt, sizeof (fmt)) != 0)
17028 return (EFAULT);
17029
17030 mutex_enter(&dtrace_lock);
17031
17032 if (fmt.dtfd_format == 0 ||
17033 fmt.dtfd_format > state->dts_nformats) {
17034 mutex_exit(&dtrace_lock);
17035 return (EINVAL);
17036 }
17037
17038 /*
17039 * Format strings are allocated contiguously and they are
17040 * never freed; if a format index is less than the number
17041 * of formats, we can assert that the format map is non-NULL
17042 * and that the format for the specified index is non-NULL.
17043 */
17044 ASSERT(state->dts_formats != NULL);
17045 str = state->dts_formats[fmt.dtfd_format - 1];
17046 ASSERT(str != NULL);
17047
17048 len = strlen(str) + 1;
17049
17050 if (len > fmt.dtfd_length) {
17051 fmt.dtfd_length = len;
17052
17053 if (copyout(&fmt, (void *)arg, sizeof (fmt)) != 0) {
17054 mutex_exit(&dtrace_lock);
17055 return (EINVAL);
17056 }
17057 } else {
17058 if (copyout(str, fmt.dtfd_string, len) != 0) {
17059 mutex_exit(&dtrace_lock);
17060 return (EINVAL);
17061 }
17062 }
17063
17064 mutex_exit(&dtrace_lock);
17065 return (0);
17066 }
17067
17068 default:
17069 break;
17070 }
17071
17072 return (ENOTTY);
17073 }
17074
17075 /*ARGSUSED*/
17076 static int
17077 dtrace_detach(dev_info_t *dip, ddi_detach_cmd_t cmd)
17078 {
17079 dtrace_state_t *state;
17080
17081 switch (cmd) {
17082 case DDI_DETACH:
17083 break;
17084
17085 case DDI_SUSPEND:
17086 return (DDI_SUCCESS);
17087
17088 default:
17089 return (DDI_FAILURE);
17090 }
17091
17092 mutex_enter(&cpu_lock);
17093 mutex_enter(&dtrace_provider_lock);
17094 mutex_enter(&dtrace_lock);
17095
17096 ASSERT(dtrace_opens == 0);
17097
17098 if (dtrace_helpers > 0) {
17099 mutex_exit(&dtrace_provider_lock);
17100 mutex_exit(&dtrace_lock);
17101 mutex_exit(&cpu_lock);
17102 return (DDI_FAILURE);
17103 }
17104
17105 if (dtrace_unregister((dtrace_provider_id_t)dtrace_provider) != 0) {
17106 mutex_exit(&dtrace_provider_lock);
17107 mutex_exit(&dtrace_lock);
17108 mutex_exit(&cpu_lock);
17109 return (DDI_FAILURE);
17110 }
17111
17112 dtrace_provider = NULL;
17113
17114 if ((state = dtrace_anon_grab()) != NULL) {
17115 /*
17116 * If there were ECBs on this state, the provider should
17117 * have not been allowed to detach; assert that there is
17118 * none.
17119 */
17120 ASSERT(state->dts_necbs == 0);
17121 dtrace_state_destroy(state);
17122
17123 /*
17124 * If we're being detached with anonymous state, we need to
17125 * indicate to the kernel debugger that DTrace is now inactive.
17126 */
17127 (void) kdi_dtrace_set(KDI_DTSET_DTRACE_DEACTIVATE);
17128 }
17129
17130 bzero(&dtrace_anon, sizeof (dtrace_anon_t));
17131 unregister_cpu_setup_func((cpu_setup_func_t *)dtrace_cpu_setup, NULL);
17132 dtrace_cpu_init = NULL;
17133 dtrace_helpers_cleanup = NULL;
17134 dtrace_helpers_fork = NULL;
17135 dtrace_cpustart_init = NULL;
17136 dtrace_cpustart_fini = NULL;
17137 dtrace_debugger_init = NULL;
17138 dtrace_debugger_fini = NULL;
17139 dtrace_modload = NULL;
17140 dtrace_modunload = NULL;
17141
17142 ASSERT(dtrace_getf == 0);
17143 ASSERT(dtrace_closef == NULL);
17144
17145 mutex_exit(&cpu_lock);
17146
17147 kmem_free(dtrace_probes, dtrace_nprobes * sizeof (dtrace_probe_t *));
17148 dtrace_probes = NULL;
17149 dtrace_nprobes = 0;
17150
17151 dtrace_hash_destroy(dtrace_bymod);
17152 dtrace_hash_destroy(dtrace_byfunc);
17153 dtrace_hash_destroy(dtrace_byname);
17154 dtrace_bymod = NULL;
17155 dtrace_byfunc = NULL;
17156 dtrace_byname = NULL;
17157
17158 kmem_cache_destroy(dtrace_state_cache);
17159 vmem_destroy(dtrace_minor);
17160 vmem_destroy(dtrace_arena);
17161
17162 if (dtrace_toxrange != NULL) {
17163 kmem_free(dtrace_toxrange,
17164 dtrace_toxranges_max * sizeof (dtrace_toxrange_t));
17165 dtrace_toxrange = NULL;
17166 dtrace_toxranges = 0;
17167 dtrace_toxranges_max = 0;
17168 }
17169
17170 ddi_remove_minor_node(dtrace_devi, NULL);
17171 dtrace_devi = NULL;
17172
17173 ddi_soft_state_fini(&dtrace_softstate);
17174
17175 ASSERT(dtrace_vtime_references == 0);
17176 ASSERT(dtrace_opens == 0);
17177 ASSERT(dtrace_retained == NULL);
17178
17179 mutex_exit(&dtrace_lock);
17180 mutex_exit(&dtrace_provider_lock);
17181
17182 /*
17183 * We don't destroy the task queue until after we have dropped our
17184 * locks (taskq_destroy() may block on running tasks). To prevent
17185 * attempting to do work after we have effectively detached but before
17186 * the task queue has been destroyed, all tasks dispatched via the
17187 * task queue must check that DTrace is still attached before
17188 * performing any operation.
17189 */
17190 taskq_destroy(dtrace_taskq);
17191 dtrace_taskq = NULL;
17192
17193 return (DDI_SUCCESS);
17194 }
17195
17196 /*ARGSUSED*/
17197 static int
17198 dtrace_info(dev_info_t *dip, ddi_info_cmd_t infocmd, void *arg, void **result)
17199 {
17200 int error;
17201
17202 switch (infocmd) {
17203 case DDI_INFO_DEVT2DEVINFO:
17204 *result = (void *)dtrace_devi;
17205 error = DDI_SUCCESS;
17206 break;
17207 case DDI_INFO_DEVT2INSTANCE:
17208 *result = (void *)0;
17209 error = DDI_SUCCESS;
17210 break;
17211 default:
17212 error = DDI_FAILURE;
17213 }
17214 return (error);
17215 }
17216
17217 static struct cb_ops dtrace_cb_ops = {
17218 dtrace_open, /* open */
17219 dtrace_close, /* close */
17220 nulldev, /* strategy */
17221 nulldev, /* print */
17222 nodev, /* dump */
17223 nodev, /* read */
17224 nodev, /* write */
17225 dtrace_ioctl, /* ioctl */
17226 nodev, /* devmap */
17227 nodev, /* mmap */
17228 nodev, /* segmap */
17229 nochpoll, /* poll */
17230 ddi_prop_op, /* cb_prop_op */
17231 0, /* streamtab */
17232 D_NEW | D_MP /* Driver compatibility flag */
17233 };
17234
17235 static struct dev_ops dtrace_ops = {
17236 DEVO_REV, /* devo_rev */
17237 0, /* refcnt */
17238 dtrace_info, /* get_dev_info */
17239 nulldev, /* identify */
17240 nulldev, /* probe */
17241 dtrace_attach, /* attach */
17242 dtrace_detach, /* detach */
17243 nodev, /* reset */
17244 &dtrace_cb_ops, /* driver operations */
17245 NULL, /* bus operations */
17246 nodev, /* dev power */
17247 ddi_quiesce_not_needed, /* quiesce */
17248 };
17249
17250 static struct modldrv modldrv = {
17251 &mod_driverops, /* module type (this is a pseudo driver) */
17252 "Dynamic Tracing", /* name of module */
17253 &dtrace_ops, /* driver ops */
17254 };
17255
17256 static struct modlinkage modlinkage = {
17257 MODREV_1,
17258 (void *)&modldrv,
17259 NULL
17260 };
17261
17262 int
17263 _init(void)
17264 {
17265 return (mod_install(&modlinkage));
17266 }
17267
17268 int
17269 _info(struct modinfo *modinfop)
17270 {
17271 return (mod_info(&modlinkage, modinfop));
17272 }
17273
17274 int
17275 _fini(void)
17276 {
17277 return (mod_remove(&modlinkage));
17278 }