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) 2013, Joyent, Inc. All rights reserved.
25 * Copyright (c) 2012 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
96 /*
97 * DTrace Tunable Variables
98 *
99 * The following variables may be tuned by adding a line to /etc/system that
100 * includes both the name of the DTrace module ("dtrace") and the name of the
101 * variable. For example:
102 *
103 * set dtrace:dtrace_destructive_disallow = 1
104 *
105 * In general, the only variables that one should be tuning this way are those
106 * that affect system-wide DTrace behavior, and for which the default behavior
107 * is undesirable. Most of these variables are tunable on a per-consumer
108 * basis using DTrace options, and need not be tuned on a system-wide basis.
109 * When tuning these variables, avoid pathological values; while some attempt
110 * is made to verify the integrity of these variables, they are not considered
111 * part of the supported interface to DTrace, and they are therefore not
112 * checked comprehensively. Further, these variables should not be tuned
113 * dynamically via "mdb -kw" or other means; they should only be tuned via
114 * /etc/system.
115 */
116 int dtrace_destructive_disallow = 0;
117 dtrace_optval_t dtrace_nonroot_maxsize = (16 * 1024 * 1024);
118 size_t dtrace_difo_maxsize = (256 * 1024);
119 dtrace_optval_t dtrace_dof_maxsize = (256 * 1024);
120 size_t dtrace_global_maxsize = (16 * 1024);
121 size_t dtrace_actions_max = (16 * 1024);
122 size_t dtrace_retain_max = 1024;
123 dtrace_optval_t dtrace_helper_actions_max = 1024;
124 dtrace_optval_t dtrace_helper_providers_max = 32;
125 dtrace_optval_t dtrace_dstate_defsize = (1 * 1024 * 1024);
126 size_t dtrace_strsize_default = 256;
127 dtrace_optval_t dtrace_cleanrate_default = 9900990; /* 101 hz */
128 dtrace_optval_t dtrace_cleanrate_min = 200000; /* 5000 hz */
129 dtrace_optval_t dtrace_cleanrate_max = (uint64_t)60 * NANOSEC; /* 1/minute */
130 dtrace_optval_t dtrace_aggrate_default = NANOSEC; /* 1 hz */
131 dtrace_optval_t dtrace_statusrate_default = NANOSEC; /* 1 hz */
132 dtrace_optval_t dtrace_statusrate_max = (hrtime_t)10 * NANOSEC; /* 6/minute */
133 dtrace_optval_t dtrace_switchrate_default = NANOSEC; /* 1 hz */
134 dtrace_optval_t dtrace_nspec_default = 1;
135 dtrace_optval_t dtrace_specsize_default = 32 * 1024;
136 dtrace_optval_t dtrace_stackframes_default = 20;
137 dtrace_optval_t dtrace_ustackframes_default = 20;
138 dtrace_optval_t dtrace_jstackframes_default = 50;
139 dtrace_optval_t dtrace_jstackstrsize_default = 512;
140 int dtrace_msgdsize_max = 128;
141 hrtime_t dtrace_chill_max = 500 * (NANOSEC / MILLISEC); /* 500 ms */
142 hrtime_t dtrace_chill_interval = NANOSEC; /* 1000 ms */
143 int dtrace_devdepth_max = 32;
144 int dtrace_err_verbose;
145 hrtime_t dtrace_deadman_interval = NANOSEC;
146 hrtime_t dtrace_deadman_timeout = (hrtime_t)10 * NANOSEC;
147 hrtime_t dtrace_deadman_user = (hrtime_t)30 * NANOSEC;
148 hrtime_t dtrace_unregister_defunct_reap = (hrtime_t)60 * NANOSEC;
149
150 /*
151 * DTrace External Variables
152 *
153 * As dtrace(7D) is a kernel module, any DTrace variables are obviously
154 * available to DTrace consumers via the backtick (`) syntax. One of these,
155 * dtrace_zero, is made deliberately so: it is provided as a source of
156 * well-known, zero-filled memory. While this variable is not documented,
157 * it is used by some translators as an implementation detail.
158 */
159 const char dtrace_zero[256] = { 0 }; /* zero-filled memory */
160
161 /*
162 * DTrace Internal Variables
163 */
164 static dev_info_t *dtrace_devi; /* device info */
165 static vmem_t *dtrace_arena; /* probe ID arena */
166 static vmem_t *dtrace_minor; /* minor number arena */
167 static taskq_t *dtrace_taskq; /* task queue */
168 static dtrace_probe_t **dtrace_probes; /* array of all probes */
169 static int dtrace_nprobes; /* number of probes */
170 static dtrace_provider_t *dtrace_provider; /* provider list */
171 static dtrace_meta_t *dtrace_meta_pid; /* user-land meta provider */
172 static int dtrace_opens; /* number of opens */
173 static int dtrace_helpers; /* number of helpers */
174 static void *dtrace_softstate; /* softstate pointer */
175 static dtrace_hash_t *dtrace_bymod; /* probes hashed by module */
176 static dtrace_hash_t *dtrace_byfunc; /* probes hashed by function */
177 static dtrace_hash_t *dtrace_byname; /* probes hashed by name */
178 static dtrace_toxrange_t *dtrace_toxrange; /* toxic range array */
179 static int dtrace_toxranges; /* number of toxic ranges */
180 static int dtrace_toxranges_max; /* size of toxic range array */
181 static dtrace_anon_t dtrace_anon; /* anonymous enabling */
182 static kmem_cache_t *dtrace_state_cache; /* cache for dynamic state */
183 static uint64_t dtrace_vtime_references; /* number of vtimestamp refs */
184 static kthread_t *dtrace_panicked; /* panicking thread */
185 static dtrace_ecb_t *dtrace_ecb_create_cache; /* cached created ECB */
186 static dtrace_genid_t dtrace_probegen; /* current probe generation */
187 static dtrace_helpers_t *dtrace_deferred_pid; /* deferred helper list */
188 static dtrace_enabling_t *dtrace_retained; /* list of retained enablings */
189 static dtrace_genid_t dtrace_retained_gen; /* current retained enab gen */
190 static dtrace_dynvar_t dtrace_dynhash_sink; /* end of dynamic hash chains */
191 static int dtrace_dynvar_failclean; /* dynvars failed to clean */
192
193 /*
194 * DTrace Locking
195 * DTrace is protected by three (relatively coarse-grained) locks:
196 *
197 * (1) dtrace_lock is required to manipulate essentially any DTrace state,
198 * including enabling state, probes, ECBs, consumer state, helper state,
199 * etc. Importantly, dtrace_lock is _not_ required when in probe context;
200 * probe context is lock-free -- synchronization is handled via the
201 * dtrace_sync() cross call mechanism.
202 *
203 * (2) dtrace_provider_lock is required when manipulating provider state, or
204 * when provider state must be held constant.
205 *
206 * (3) dtrace_meta_lock is required when manipulating meta provider state, or
207 * when meta provider state must be held constant.
208 *
209 * The lock ordering between these three locks is dtrace_meta_lock before
210 * dtrace_provider_lock before dtrace_lock. (In particular, there are
211 * several places where dtrace_provider_lock is held by the framework as it
212 * calls into the providers -- which then call back into the framework,
213 * grabbing dtrace_lock.)
214 *
215 * There are two other locks in the mix: mod_lock and cpu_lock. With respect
216 * to dtrace_provider_lock and dtrace_lock, cpu_lock continues its historical
217 * role as a coarse-grained lock; it is acquired before both of these locks.
218 * With respect to dtrace_meta_lock, its behavior is stranger: cpu_lock must
219 * be acquired _between_ dtrace_meta_lock and any other DTrace locks.
220 * mod_lock is similar with respect to dtrace_provider_lock in that it must be
221 * acquired _between_ dtrace_provider_lock and dtrace_lock.
222 */
223 static kmutex_t dtrace_lock; /* probe state lock */
224 static kmutex_t dtrace_provider_lock; /* provider state lock */
225 static kmutex_t dtrace_meta_lock; /* meta-provider state lock */
226
227 /*
228 * DTrace Provider Variables
229 *
230 * These are the variables relating to DTrace as a provider (that is, the
231 * provider of the BEGIN, END, and ERROR probes).
232 */
233 static dtrace_pattr_t dtrace_provider_attr = {
234 { DTRACE_STABILITY_STABLE, DTRACE_STABILITY_STABLE, DTRACE_CLASS_COMMON },
235 { DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN },
236 { DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN },
237 { DTRACE_STABILITY_STABLE, DTRACE_STABILITY_STABLE, DTRACE_CLASS_COMMON },
238 { DTRACE_STABILITY_STABLE, DTRACE_STABILITY_STABLE, DTRACE_CLASS_COMMON },
239 };
240
241 static void
242 dtrace_nullop(void)
243 {}
244
245 static int
246 dtrace_enable_nullop(void)
247 {
248 return (0);
249 }
250
251 static dtrace_pops_t dtrace_provider_ops = {
252 (void (*)(void *, const dtrace_probedesc_t *))dtrace_nullop,
253 (void (*)(void *, struct modctl *))dtrace_nullop,
254 (int (*)(void *, dtrace_id_t, void *))dtrace_enable_nullop,
255 (void (*)(void *, dtrace_id_t, void *))dtrace_nullop,
256 (void (*)(void *, dtrace_id_t, void *))dtrace_nullop,
257 (void (*)(void *, dtrace_id_t, void *))dtrace_nullop,
258 NULL,
259 NULL,
260 NULL,
261 (void (*)(void *, dtrace_id_t, void *))dtrace_nullop
262 };
263
264 static dtrace_id_t dtrace_probeid_begin; /* special BEGIN probe */
265 static dtrace_id_t dtrace_probeid_end; /* special END probe */
266 dtrace_id_t dtrace_probeid_error; /* special ERROR probe */
267
268 /*
269 * DTrace Helper Tracing Variables
270 */
271 uint32_t dtrace_helptrace_next = 0;
272 uint32_t dtrace_helptrace_nlocals;
273 char *dtrace_helptrace_buffer;
274 int dtrace_helptrace_bufsize = 512 * 1024;
275
276 #ifdef DEBUG
277 int dtrace_helptrace_enabled = 1;
278 #else
279 int dtrace_helptrace_enabled = 0;
280 #endif
281
282 /*
283 * DTrace Error Hashing
284 *
285 * On DEBUG kernels, DTrace will track the errors that has seen in a hash
286 * table. This is very useful for checking coverage of tests that are
287 * expected to induce DIF or DOF processing errors, and may be useful for
288 * debugging problems in the DIF code generator or in DOF generation . The
289 * error hash may be examined with the ::dtrace_errhash MDB dcmd.
290 */
291 #ifdef DEBUG
292 static dtrace_errhash_t dtrace_errhash[DTRACE_ERRHASHSZ];
293 static const char *dtrace_errlast;
294 static kthread_t *dtrace_errthread;
295 static kmutex_t dtrace_errlock;
296 #endif
297
298 /*
299 * DTrace Macros and Constants
300 *
301 * These are various macros that are useful in various spots in the
302 * implementation, along with a few random constants that have no meaning
303 * outside of the implementation. There is no real structure to this cpp
304 * mishmash -- but is there ever?
305 */
306 #define DTRACE_HASHSTR(hash, probe) \
307 dtrace_hash_str(*((char **)((uintptr_t)(probe) + (hash)->dth_stroffs)))
308
309 #define DTRACE_HASHNEXT(hash, probe) \
310 (dtrace_probe_t **)((uintptr_t)(probe) + (hash)->dth_nextoffs)
311
312 #define DTRACE_HASHPREV(hash, probe) \
313 (dtrace_probe_t **)((uintptr_t)(probe) + (hash)->dth_prevoffs)
314
315 #define DTRACE_HASHEQ(hash, lhs, rhs) \
316 (strcmp(*((char **)((uintptr_t)(lhs) + (hash)->dth_stroffs)), \
317 *((char **)((uintptr_t)(rhs) + (hash)->dth_stroffs))) == 0)
318
319 #define DTRACE_AGGHASHSIZE_SLEW 17
320
321 #define DTRACE_V4MAPPED_OFFSET (sizeof (uint32_t) * 3)
322
323 /*
324 * The key for a thread-local variable consists of the lower 61 bits of the
325 * t_did, plus the 3 bits of the highest active interrupt above LOCK_LEVEL.
326 * We add DIF_VARIABLE_MAX to t_did to assure that the thread key is never
327 * equal to a variable identifier. This is necessary (but not sufficient) to
328 * assure that global associative arrays never collide with thread-local
329 * variables. To guarantee that they cannot collide, we must also define the
330 * order for keying dynamic variables. That order is:
331 *
332 * [ key0 ] ... [ keyn ] [ variable-key ] [ tls-key ]
333 *
334 * Because the variable-key and the tls-key are in orthogonal spaces, there is
335 * no way for a global variable key signature to match a thread-local key
336 * signature.
337 */
338 #define DTRACE_TLS_THRKEY(where) { \
339 uint_t intr = 0; \
340 uint_t actv = CPU->cpu_intr_actv >> (LOCK_LEVEL + 1); \
341 for (; actv; actv >>= 1) \
342 intr++; \
343 ASSERT(intr < (1 << 3)); \
344 (where) = ((curthread->t_did + DIF_VARIABLE_MAX) & \
345 (((uint64_t)1 << 61) - 1)) | ((uint64_t)intr << 61); \
346 }
347
348 #define DT_BSWAP_8(x) ((x) & 0xff)
349 #define DT_BSWAP_16(x) ((DT_BSWAP_8(x) << 8) | DT_BSWAP_8((x) >> 8))
350 #define DT_BSWAP_32(x) ((DT_BSWAP_16(x) << 16) | DT_BSWAP_16((x) >> 16))
351 #define DT_BSWAP_64(x) ((DT_BSWAP_32(x) << 32) | DT_BSWAP_32((x) >> 32))
352
353 #define DT_MASK_LO 0x00000000FFFFFFFFULL
354
355 #define DTRACE_STORE(type, tomax, offset, what) \
356 *((type *)((uintptr_t)(tomax) + (uintptr_t)offset)) = (type)(what);
357
358 #ifndef __x86
359 #define DTRACE_ALIGNCHECK(addr, size, flags) \
360 if (addr & (size - 1)) { \
361 *flags |= CPU_DTRACE_BADALIGN; \
362 cpu_core[CPU->cpu_id].cpuc_dtrace_illval = addr; \
363 return (0); \
364 }
365 #else
366 #define DTRACE_ALIGNCHECK(addr, size, flags)
367 #endif
368
369 /*
370 * Test whether a range of memory starting at testaddr of size testsz falls
371 * within the range of memory described by addr, sz. We take care to avoid
372 * problems with overflow and underflow of the unsigned quantities, and
373 * disallow all negative sizes. Ranges of size 0 are allowed.
374 */
375 #define DTRACE_INRANGE(testaddr, testsz, baseaddr, basesz) \
376 ((testaddr) - (baseaddr) < (basesz) && \
377 (testaddr) + (testsz) - (baseaddr) <= (basesz) && \
378 (testaddr) + (testsz) >= (testaddr))
379
380 /*
381 * Test whether alloc_sz bytes will fit in the scratch region. We isolate
382 * alloc_sz on the righthand side of the comparison in order to avoid overflow
383 * or underflow in the comparison with it. This is simpler than the INRANGE
384 * check above, because we know that the dtms_scratch_ptr is valid in the
385 * range. Allocations of size zero are allowed.
386 */
387 #define DTRACE_INSCRATCH(mstate, alloc_sz) \
388 ((mstate)->dtms_scratch_base + (mstate)->dtms_scratch_size - \
389 (mstate)->dtms_scratch_ptr >= (alloc_sz))
390
391 #define DTRACE_LOADFUNC(bits) \
392 /*CSTYLED*/ \
393 uint##bits##_t \
394 dtrace_load##bits(uintptr_t addr) \
395 { \
396 size_t size = bits / NBBY; \
397 /*CSTYLED*/ \
398 uint##bits##_t rval; \
399 int i; \
400 volatile uint16_t *flags = (volatile uint16_t *) \
401 &cpu_core[CPU->cpu_id].cpuc_dtrace_flags; \
402 \
403 DTRACE_ALIGNCHECK(addr, size, flags); \
404 \
405 for (i = 0; i < dtrace_toxranges; i++) { \
406 if (addr >= dtrace_toxrange[i].dtt_limit) \
407 continue; \
408 \
409 if (addr + size <= dtrace_toxrange[i].dtt_base) \
410 continue; \
411 \
412 /* \
413 * This address falls within a toxic region; return 0. \
414 */ \
415 *flags |= CPU_DTRACE_BADADDR; \
416 cpu_core[CPU->cpu_id].cpuc_dtrace_illval = addr; \
417 return (0); \
418 } \
419 \
420 *flags |= CPU_DTRACE_NOFAULT; \
421 /*CSTYLED*/ \
422 rval = *((volatile uint##bits##_t *)addr); \
423 *flags &= ~CPU_DTRACE_NOFAULT; \
424 \
425 return (!(*flags & CPU_DTRACE_FAULT) ? rval : 0); \
426 }
427
428 #ifdef _LP64
429 #define dtrace_loadptr dtrace_load64
430 #else
431 #define dtrace_loadptr dtrace_load32
432 #endif
433
434 #define DTRACE_DYNHASH_FREE 0
435 #define DTRACE_DYNHASH_SINK 1
436 #define DTRACE_DYNHASH_VALID 2
437
438 #define DTRACE_MATCH_FAIL -1
439 #define DTRACE_MATCH_NEXT 0
440 #define DTRACE_MATCH_DONE 1
441 #define DTRACE_ANCHORED(probe) ((probe)->dtpr_func[0] != '\0')
442 #define DTRACE_STATE_ALIGN 64
443
444 #define DTRACE_FLAGS2FLT(flags) \
445 (((flags) & CPU_DTRACE_BADADDR) ? DTRACEFLT_BADADDR : \
446 ((flags) & CPU_DTRACE_ILLOP) ? DTRACEFLT_ILLOP : \
447 ((flags) & CPU_DTRACE_DIVZERO) ? DTRACEFLT_DIVZERO : \
448 ((flags) & CPU_DTRACE_KPRIV) ? DTRACEFLT_KPRIV : \
449 ((flags) & CPU_DTRACE_UPRIV) ? DTRACEFLT_UPRIV : \
450 ((flags) & CPU_DTRACE_TUPOFLOW) ? DTRACEFLT_TUPOFLOW : \
451 ((flags) & CPU_DTRACE_BADALIGN) ? DTRACEFLT_BADALIGN : \
452 ((flags) & CPU_DTRACE_NOSCRATCH) ? DTRACEFLT_NOSCRATCH : \
453 ((flags) & CPU_DTRACE_BADSTACK) ? DTRACEFLT_BADSTACK : \
454 DTRACEFLT_UNKNOWN)
455
456 #define DTRACEACT_ISSTRING(act) \
457 ((act)->dta_kind == DTRACEACT_DIFEXPR && \
458 (act)->dta_difo->dtdo_rtype.dtdt_kind == DIF_TYPE_STRING)
459
460 static size_t dtrace_strlen(const char *, size_t);
461 static dtrace_probe_t *dtrace_probe_lookup_id(dtrace_id_t id);
462 static void dtrace_enabling_provide(dtrace_provider_t *);
463 static int dtrace_enabling_match(dtrace_enabling_t *, int *);
464 static void dtrace_enabling_matchall(void);
465 static void dtrace_enabling_reap(void);
466 static dtrace_state_t *dtrace_anon_grab(void);
467 static uint64_t dtrace_helper(int, dtrace_mstate_t *,
468 dtrace_state_t *, uint64_t, uint64_t);
469 static dtrace_helpers_t *dtrace_helpers_create(proc_t *);
470 static void dtrace_buffer_drop(dtrace_buffer_t *);
471 static int dtrace_buffer_consumed(dtrace_buffer_t *, hrtime_t when);
472 static intptr_t dtrace_buffer_reserve(dtrace_buffer_t *, size_t, size_t,
473 dtrace_state_t *, dtrace_mstate_t *);
474 static int dtrace_state_option(dtrace_state_t *, dtrace_optid_t,
475 dtrace_optval_t);
476 static int dtrace_ecb_create_enable(dtrace_probe_t *, void *);
477 static void dtrace_helper_provider_destroy(dtrace_helper_provider_t *);
478
479 /*
480 * DTrace Probe Context Functions
481 *
482 * These functions are called from probe context. Because probe context is
483 * any context in which C may be called, arbitrarily locks may be held,
484 * interrupts may be disabled, we may be in arbitrary dispatched state, etc.
485 * As a result, functions called from probe context may only call other DTrace
486 * support functions -- they may not interact at all with the system at large.
487 * (Note that the ASSERT macro is made probe-context safe by redefining it in
488 * terms of dtrace_assfail(), a probe-context safe function.) If arbitrary
489 * loads are to be performed from probe context, they _must_ be in terms of
490 * the safe dtrace_load*() variants.
491 *
492 * Some functions in this block are not actually called from probe context;
493 * for these functions, there will be a comment above the function reading
494 * "Note: not called from probe context."
495 */
496 void
497 dtrace_panic(const char *format, ...)
498 {
499 va_list alist;
500
501 va_start(alist, format);
502 dtrace_vpanic(format, alist);
503 va_end(alist);
504 }
505
506 int
507 dtrace_assfail(const char *a, const char *f, int l)
508 {
509 dtrace_panic("assertion failed: %s, file: %s, line: %d", a, f, l);
510
511 /*
512 * We just need something here that even the most clever compiler
513 * cannot optimize away.
514 */
515 return (a[(uintptr_t)f]);
516 }
517
518 /*
519 * Atomically increment a specified error counter from probe context.
520 */
521 static void
522 dtrace_error(uint32_t *counter)
523 {
524 /*
525 * Most counters stored to in probe context are per-CPU counters.
526 * However, there are some error conditions that are sufficiently
527 * arcane that they don't merit per-CPU storage. If these counters
528 * are incremented concurrently on different CPUs, scalability will be
529 * adversely affected -- but we don't expect them to be white-hot in a
530 * correctly constructed enabling...
531 */
532 uint32_t oval, nval;
533
534 do {
535 oval = *counter;
536
537 if ((nval = oval + 1) == 0) {
538 /*
539 * If the counter would wrap, set it to 1 -- assuring
540 * that the counter is never zero when we have seen
541 * errors. (The counter must be 32-bits because we
542 * aren't guaranteed a 64-bit compare&swap operation.)
543 * To save this code both the infamy of being fingered
544 * by a priggish news story and the indignity of being
545 * the target of a neo-puritan witch trial, we're
546 * carefully avoiding any colorful description of the
547 * likelihood of this condition -- but suffice it to
548 * say that it is only slightly more likely than the
549 * overflow of predicate cache IDs, as discussed in
550 * dtrace_predicate_create().
551 */
552 nval = 1;
553 }
554 } while (dtrace_cas32(counter, oval, nval) != oval);
555 }
556
557 /*
558 * Use the DTRACE_LOADFUNC macro to define functions for each of loading a
559 * uint8_t, a uint16_t, a uint32_t and a uint64_t.
560 */
561 DTRACE_LOADFUNC(8)
562 DTRACE_LOADFUNC(16)
563 DTRACE_LOADFUNC(32)
564 DTRACE_LOADFUNC(64)
565
566 static int
567 dtrace_inscratch(uintptr_t dest, size_t size, dtrace_mstate_t *mstate)
568 {
569 if (dest < mstate->dtms_scratch_base)
570 return (0);
571
572 if (dest + size < dest)
573 return (0);
574
575 if (dest + size > mstate->dtms_scratch_ptr)
576 return (0);
577
578 return (1);
579 }
580
581 static int
582 dtrace_canstore_statvar(uint64_t addr, size_t sz,
583 dtrace_statvar_t **svars, int nsvars)
584 {
585 int i;
586
587 for (i = 0; i < nsvars; i++) {
588 dtrace_statvar_t *svar = svars[i];
589
590 if (svar == NULL || svar->dtsv_size == 0)
591 continue;
592
593 if (DTRACE_INRANGE(addr, sz, svar->dtsv_data, svar->dtsv_size))
594 return (1);
595 }
596
597 return (0);
598 }
599
600 /*
601 * Check to see if the address is within a memory region to which a store may
602 * be issued. This includes the DTrace scratch areas, and any DTrace variable
603 * region. The caller of dtrace_canstore() is responsible for performing any
604 * alignment checks that are needed before stores are actually executed.
605 */
606 static int
607 dtrace_canstore(uint64_t addr, size_t sz, dtrace_mstate_t *mstate,
608 dtrace_vstate_t *vstate)
609 {
610 /*
611 * First, check to see if the address is in scratch space...
612 */
613 if (DTRACE_INRANGE(addr, sz, mstate->dtms_scratch_base,
614 mstate->dtms_scratch_size))
615 return (1);
616
617 /*
618 * Now check to see if it's a dynamic variable. This check will pick
619 * up both thread-local variables and any global dynamically-allocated
620 * variables.
621 */
622 if (DTRACE_INRANGE(addr, sz, (uintptr_t)vstate->dtvs_dynvars.dtds_base,
623 vstate->dtvs_dynvars.dtds_size)) {
624 dtrace_dstate_t *dstate = &vstate->dtvs_dynvars;
625 uintptr_t base = (uintptr_t)dstate->dtds_base +
626 (dstate->dtds_hashsize * sizeof (dtrace_dynhash_t));
627 uintptr_t chunkoffs;
628
629 /*
630 * Before we assume that we can store here, we need to make
631 * sure that it isn't in our metadata -- storing to our
632 * dynamic variable metadata would corrupt our state. For
633 * the range to not include any dynamic variable metadata,
634 * it must:
635 *
636 * (1) Start above the hash table that is at the base of
637 * the dynamic variable space
638 *
639 * (2) Have a starting chunk offset that is beyond the
640 * dtrace_dynvar_t that is at the base of every chunk
641 *
642 * (3) Not span a chunk boundary
643 *
644 */
645 if (addr < base)
646 return (0);
647
648 chunkoffs = (addr - base) % dstate->dtds_chunksize;
649
650 if (chunkoffs < sizeof (dtrace_dynvar_t))
651 return (0);
652
653 if (chunkoffs + sz > dstate->dtds_chunksize)
654 return (0);
655
656 return (1);
657 }
658
659 /*
660 * Finally, check the static local and global variables. These checks
661 * take the longest, so we perform them last.
662 */
663 if (dtrace_canstore_statvar(addr, sz,
664 vstate->dtvs_locals, vstate->dtvs_nlocals))
665 return (1);
666
667 if (dtrace_canstore_statvar(addr, sz,
668 vstate->dtvs_globals, vstate->dtvs_nglobals))
669 return (1);
670
671 return (0);
672 }
673
674
675 /*
676 * Convenience routine to check to see if the address is within a memory
677 * region in which a load may be issued given the user's privilege level;
678 * if not, it sets the appropriate error flags and loads 'addr' into the
679 * illegal value slot.
680 *
681 * DTrace subroutines (DIF_SUBR_*) should use this helper to implement
682 * appropriate memory access protection.
683 */
684 static int
685 dtrace_canload(uint64_t addr, size_t sz, dtrace_mstate_t *mstate,
686 dtrace_vstate_t *vstate)
687 {
688 volatile uintptr_t *illval = &cpu_core[CPU->cpu_id].cpuc_dtrace_illval;
689
690 /*
691 * If we hold the privilege to read from kernel memory, then
692 * everything is readable.
693 */
694 if ((mstate->dtms_access & DTRACE_ACCESS_KERNEL) != 0)
695 return (1);
696
697 /*
698 * You can obviously read that which you can store.
699 */
700 if (dtrace_canstore(addr, sz, mstate, vstate))
701 return (1);
702
703 /*
704 * We're allowed to read from our own string table.
705 */
706 if (DTRACE_INRANGE(addr, sz, (uintptr_t)mstate->dtms_difo->dtdo_strtab,
707 mstate->dtms_difo->dtdo_strlen))
708 return (1);
709
710 DTRACE_CPUFLAG_SET(CPU_DTRACE_KPRIV);
711 *illval = addr;
712 return (0);
713 }
714
715 /*
716 * Convenience routine to check to see if a given string is within a memory
717 * region in which a load may be issued given the user's privilege level;
718 * this exists so that we don't need to issue unnecessary dtrace_strlen()
719 * calls in the event that the user has all privileges.
720 */
721 static int
722 dtrace_strcanload(uint64_t addr, size_t sz, dtrace_mstate_t *mstate,
723 dtrace_vstate_t *vstate)
724 {
725 size_t strsz;
726
727 /*
728 * If we hold the privilege to read from kernel memory, then
729 * everything is readable.
730 */
731 if ((mstate->dtms_access & DTRACE_ACCESS_KERNEL) != 0)
732 return (1);
733
734 strsz = 1 + dtrace_strlen((char *)(uintptr_t)addr, sz);
735 if (dtrace_canload(addr, strsz, mstate, vstate))
736 return (1);
737
738 return (0);
739 }
740
741 /*
742 * Convenience routine to check to see if a given variable is within a memory
743 * region in which a load may be issued given the user's privilege level.
744 */
745 static int
746 dtrace_vcanload(void *src, dtrace_diftype_t *type, dtrace_mstate_t *mstate,
747 dtrace_vstate_t *vstate)
748 {
749 size_t sz;
750 ASSERT(type->dtdt_flags & DIF_TF_BYREF);
751
752 /*
753 * If we hold the privilege to read from kernel memory, then
754 * everything is readable.
755 */
756 if ((mstate->dtms_access & DTRACE_ACCESS_KERNEL) != 0)
757 return (1);
758
759 if (type->dtdt_kind == DIF_TYPE_STRING)
760 sz = dtrace_strlen(src,
761 vstate->dtvs_state->dts_options[DTRACEOPT_STRSIZE]) + 1;
762 else
763 sz = type->dtdt_size;
764
765 return (dtrace_canload((uintptr_t)src, sz, mstate, vstate));
766 }
767
768 /*
769 * Compare two strings using safe loads.
770 */
771 static int
772 dtrace_strncmp(char *s1, char *s2, size_t limit)
773 {
774 uint8_t c1, c2;
775 volatile uint16_t *flags;
776
777 if (s1 == s2 || limit == 0)
778 return (0);
779
780 flags = (volatile uint16_t *)&cpu_core[CPU->cpu_id].cpuc_dtrace_flags;
781
782 do {
783 if (s1 == NULL) {
784 c1 = '\0';
785 } else {
786 c1 = dtrace_load8((uintptr_t)s1++);
787 }
788
789 if (s2 == NULL) {
790 c2 = '\0';
791 } else {
792 c2 = dtrace_load8((uintptr_t)s2++);
793 }
794
795 if (c1 != c2)
796 return (c1 - c2);
797 } while (--limit && c1 != '\0' && !(*flags & CPU_DTRACE_FAULT));
798
799 return (0);
800 }
801
802 /*
803 * Compute strlen(s) for a string using safe memory accesses. The additional
804 * len parameter is used to specify a maximum length to ensure completion.
805 */
806 static size_t
807 dtrace_strlen(const char *s, size_t lim)
808 {
809 uint_t len;
810
811 for (len = 0; len != lim; len++) {
812 if (dtrace_load8((uintptr_t)s++) == '\0')
813 break;
814 }
815
816 return (len);
817 }
818
819 /*
820 * Check if an address falls within a toxic region.
821 */
822 static int
823 dtrace_istoxic(uintptr_t kaddr, size_t size)
824 {
825 uintptr_t taddr, tsize;
826 int i;
827
828 for (i = 0; i < dtrace_toxranges; i++) {
829 taddr = dtrace_toxrange[i].dtt_base;
830 tsize = dtrace_toxrange[i].dtt_limit - taddr;
831
832 if (kaddr - taddr < tsize) {
833 DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR);
834 cpu_core[CPU->cpu_id].cpuc_dtrace_illval = kaddr;
835 return (1);
836 }
837
838 if (taddr - kaddr < size) {
839 DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR);
840 cpu_core[CPU->cpu_id].cpuc_dtrace_illval = taddr;
841 return (1);
842 }
843 }
844
845 return (0);
846 }
847
848 /*
849 * Copy src to dst using safe memory accesses. The src is assumed to be unsafe
850 * memory specified by the DIF program. The dst is assumed to be safe memory
851 * that we can store to directly because it is managed by DTrace. As with
852 * standard bcopy, overlapping copies are handled properly.
853 */
854 static void
855 dtrace_bcopy(const void *src, void *dst, size_t len)
856 {
857 if (len != 0) {
858 uint8_t *s1 = dst;
859 const uint8_t *s2 = src;
860
861 if (s1 <= s2) {
862 do {
863 *s1++ = dtrace_load8((uintptr_t)s2++);
864 } while (--len != 0);
865 } else {
866 s2 += len;
867 s1 += len;
868
869 do {
870 *--s1 = dtrace_load8((uintptr_t)--s2);
871 } while (--len != 0);
872 }
873 }
874 }
875
876 /*
877 * Copy src to dst using safe memory accesses, up to either the specified
878 * length, or the point that a nul byte is encountered. The src is assumed to
879 * be unsafe memory specified by the DIF program. The dst is assumed to be
880 * safe memory that we can store to directly because it is managed by DTrace.
881 * Unlike dtrace_bcopy(), overlapping regions are not handled.
882 */
883 static void
884 dtrace_strcpy(const void *src, void *dst, size_t len)
885 {
886 if (len != 0) {
887 uint8_t *s1 = dst, c;
888 const uint8_t *s2 = src;
889
890 do {
891 *s1++ = c = dtrace_load8((uintptr_t)s2++);
892 } while (--len != 0 && c != '\0');
893 }
894 }
895
896 /*
897 * Copy src to dst, deriving the size and type from the specified (BYREF)
898 * variable type. The src is assumed to be unsafe memory specified by the DIF
899 * program. The dst is assumed to be DTrace variable memory that is of the
900 * specified type; we assume that we can store to directly.
901 */
902 static void
903 dtrace_vcopy(void *src, void *dst, dtrace_diftype_t *type)
904 {
905 ASSERT(type->dtdt_flags & DIF_TF_BYREF);
906
907 if (type->dtdt_kind == DIF_TYPE_STRING) {
908 dtrace_strcpy(src, dst, type->dtdt_size);
909 } else {
910 dtrace_bcopy(src, dst, type->dtdt_size);
911 }
912 }
913
914 /*
915 * Compare s1 to s2 using safe memory accesses. The s1 data is assumed to be
916 * unsafe memory specified by the DIF program. The s2 data is assumed to be
917 * safe memory that we can access directly because it is managed by DTrace.
918 */
919 static int
920 dtrace_bcmp(const void *s1, const void *s2, size_t len)
921 {
922 volatile uint16_t *flags;
923
924 flags = (volatile uint16_t *)&cpu_core[CPU->cpu_id].cpuc_dtrace_flags;
925
926 if (s1 == s2)
927 return (0);
928
929 if (s1 == NULL || s2 == NULL)
930 return (1);
931
932 if (s1 != s2 && len != 0) {
933 const uint8_t *ps1 = s1;
934 const uint8_t *ps2 = s2;
935
936 do {
937 if (dtrace_load8((uintptr_t)ps1++) != *ps2++)
938 return (1);
939 } while (--len != 0 && !(*flags & CPU_DTRACE_FAULT));
940 }
941 return (0);
942 }
943
944 /*
945 * Zero the specified region using a simple byte-by-byte loop. Note that this
946 * is for safe DTrace-managed memory only.
947 */
948 static void
949 dtrace_bzero(void *dst, size_t len)
950 {
951 uchar_t *cp;
952
953 for (cp = dst; len != 0; len--)
954 *cp++ = 0;
955 }
956
957 static void
958 dtrace_add_128(uint64_t *addend1, uint64_t *addend2, uint64_t *sum)
959 {
960 uint64_t result[2];
961
962 result[0] = addend1[0] + addend2[0];
963 result[1] = addend1[1] + addend2[1] +
964 (result[0] < addend1[0] || result[0] < addend2[0] ? 1 : 0);
965
966 sum[0] = result[0];
967 sum[1] = result[1];
968 }
969
970 /*
971 * Shift the 128-bit value in a by b. If b is positive, shift left.
972 * If b is negative, shift right.
973 */
974 static void
975 dtrace_shift_128(uint64_t *a, int b)
976 {
977 uint64_t mask;
978
979 if (b == 0)
980 return;
981
982 if (b < 0) {
983 b = -b;
984 if (b >= 64) {
985 a[0] = a[1] >> (b - 64);
986 a[1] = 0;
987 } else {
988 a[0] >>= b;
989 mask = 1LL << (64 - b);
990 mask -= 1;
991 a[0] |= ((a[1] & mask) << (64 - b));
992 a[1] >>= b;
993 }
994 } else {
995 if (b >= 64) {
996 a[1] = a[0] << (b - 64);
997 a[0] = 0;
998 } else {
999 a[1] <<= b;
1000 mask = a[0] >> (64 - b);
1001 a[1] |= mask;
1002 a[0] <<= b;
1003 }
1004 }
1005 }
1006
1007 /*
1008 * The basic idea is to break the 2 64-bit values into 4 32-bit values,
1009 * use native multiplication on those, and then re-combine into the
1010 * resulting 128-bit value.
1011 *
1012 * (hi1 << 32 + lo1) * (hi2 << 32 + lo2) =
1013 * hi1 * hi2 << 64 +
1014 * hi1 * lo2 << 32 +
1015 * hi2 * lo1 << 32 +
1016 * lo1 * lo2
1017 */
1018 static void
1019 dtrace_multiply_128(uint64_t factor1, uint64_t factor2, uint64_t *product)
1020 {
1021 uint64_t hi1, hi2, lo1, lo2;
1022 uint64_t tmp[2];
1023
1024 hi1 = factor1 >> 32;
1025 hi2 = factor2 >> 32;
1026
1027 lo1 = factor1 & DT_MASK_LO;
1028 lo2 = factor2 & DT_MASK_LO;
1029
1030 product[0] = lo1 * lo2;
1031 product[1] = hi1 * hi2;
1032
1033 tmp[0] = hi1 * lo2;
1034 tmp[1] = 0;
1035 dtrace_shift_128(tmp, 32);
1036 dtrace_add_128(product, tmp, product);
1037
1038 tmp[0] = hi2 * lo1;
1039 tmp[1] = 0;
1040 dtrace_shift_128(tmp, 32);
1041 dtrace_add_128(product, tmp, product);
1042 }
1043
1044 /*
1045 * This privilege check should be used by actions and subroutines to
1046 * verify that the user credentials of the process that enabled the
1047 * invoking ECB match the target credentials
1048 */
1049 static int
1050 dtrace_priv_proc_common_user(dtrace_state_t *state)
1051 {
1052 cred_t *cr, *s_cr = state->dts_cred.dcr_cred;
1053
1054 /*
1055 * We should always have a non-NULL state cred here, since if cred
1056 * is null (anonymous tracing), we fast-path bypass this routine.
1057 */
1058 ASSERT(s_cr != NULL);
1059
1060 if ((cr = CRED()) != NULL &&
1061 s_cr->cr_uid == cr->cr_uid &&
1062 s_cr->cr_uid == cr->cr_ruid &&
1063 s_cr->cr_uid == cr->cr_suid &&
1064 s_cr->cr_gid == cr->cr_gid &&
1065 s_cr->cr_gid == cr->cr_rgid &&
1066 s_cr->cr_gid == cr->cr_sgid)
1067 return (1);
1068
1069 return (0);
1070 }
1071
1072 /*
1073 * This privilege check should be used by actions and subroutines to
1074 * verify that the zone of the process that enabled the invoking ECB
1075 * matches the target credentials
1076 */
1077 static int
1078 dtrace_priv_proc_common_zone(dtrace_state_t *state)
1079 {
1080 cred_t *cr, *s_cr = state->dts_cred.dcr_cred;
1081
1082 /*
1083 * We should always have a non-NULL state cred here, since if cred
1084 * is null (anonymous tracing), we fast-path bypass this routine.
1085 */
1086 ASSERT(s_cr != NULL);
1087
1088 if ((cr = CRED()) != NULL &&
1089 s_cr->cr_zone == cr->cr_zone)
1090 return (1);
1091
1092 return (0);
1093 }
1094
1095 /*
1096 * This privilege check should be used by actions and subroutines to
1097 * verify that the process has not setuid or changed credentials.
1098 */
1099 static int
1100 dtrace_priv_proc_common_nocd()
1101 {
1102 proc_t *proc;
1103
1104 if ((proc = ttoproc(curthread)) != NULL &&
1105 !(proc->p_flag & SNOCD))
1106 return (1);
1107
1108 return (0);
1109 }
1110
1111 static int
1112 dtrace_priv_proc_destructive(dtrace_state_t *state, dtrace_mstate_t *mstate)
1113 {
1114 int action = state->dts_cred.dcr_action;
1115
1116 if (!(mstate->dtms_access & DTRACE_ACCESS_PROC))
1117 goto bad;
1118
1119 if (((action & DTRACE_CRA_PROC_DESTRUCTIVE_ALLZONE) == 0) &&
1120 dtrace_priv_proc_common_zone(state) == 0)
1121 goto bad;
1122
1123 if (((action & DTRACE_CRA_PROC_DESTRUCTIVE_ALLUSER) == 0) &&
1124 dtrace_priv_proc_common_user(state) == 0)
1125 goto bad;
1126
1127 if (((action & DTRACE_CRA_PROC_DESTRUCTIVE_CREDCHG) == 0) &&
1128 dtrace_priv_proc_common_nocd() == 0)
1129 goto bad;
1130
1131 return (1);
1132
1133 bad:
1134 cpu_core[CPU->cpu_id].cpuc_dtrace_flags |= CPU_DTRACE_UPRIV;
1135
1136 return (0);
1137 }
1138
1139 static int
1140 dtrace_priv_proc_control(dtrace_state_t *state, dtrace_mstate_t *mstate)
1141 {
1142 if (mstate->dtms_access & DTRACE_ACCESS_PROC) {
1143 if (state->dts_cred.dcr_action & DTRACE_CRA_PROC_CONTROL)
1144 return (1);
1145
1146 if (dtrace_priv_proc_common_zone(state) &&
1147 dtrace_priv_proc_common_user(state) &&
1148 dtrace_priv_proc_common_nocd())
1149 return (1);
1150 }
1151
1152 cpu_core[CPU->cpu_id].cpuc_dtrace_flags |= CPU_DTRACE_UPRIV;
1153
1154 return (0);
1155 }
1156
1157 static int
1158 dtrace_priv_proc(dtrace_state_t *state, dtrace_mstate_t *mstate)
1159 {
1160 if ((mstate->dtms_access & DTRACE_ACCESS_PROC) &&
1161 (state->dts_cred.dcr_action & DTRACE_CRA_PROC))
1162 return (1);
1163
1164 cpu_core[CPU->cpu_id].cpuc_dtrace_flags |= CPU_DTRACE_UPRIV;
1165
1166 return (0);
1167 }
1168
1169 static int
1170 dtrace_priv_kernel(dtrace_state_t *state)
1171 {
1172 if (state->dts_cred.dcr_action & DTRACE_CRA_KERNEL)
1173 return (1);
1174
1175 cpu_core[CPU->cpu_id].cpuc_dtrace_flags |= CPU_DTRACE_KPRIV;
1176
1177 return (0);
1178 }
1179
1180 static int
1181 dtrace_priv_kernel_destructive(dtrace_state_t *state)
1182 {
1183 if (state->dts_cred.dcr_action & DTRACE_CRA_KERNEL_DESTRUCTIVE)
1184 return (1);
1185
1186 cpu_core[CPU->cpu_id].cpuc_dtrace_flags |= CPU_DTRACE_KPRIV;
1187
1188 return (0);
1189 }
1190
1191 /*
1192 * Determine if the dte_cond of the specified ECB allows for processing of
1193 * the current probe to continue. Note that this routine may allow continued
1194 * processing, but with access(es) stripped from the mstate's dtms_access
1195 * field.
1196 */
1197 static int
1198 dtrace_priv_probe(dtrace_state_t *state, dtrace_mstate_t *mstate,
1199 dtrace_ecb_t *ecb)
1200 {
1201 dtrace_probe_t *probe = ecb->dte_probe;
1202 dtrace_provider_t *prov = probe->dtpr_provider;
1203 dtrace_pops_t *pops = &prov->dtpv_pops;
1204 int mode = DTRACE_MODE_NOPRIV_DROP;
1205
1206 ASSERT(ecb->dte_cond);
1207
1208 if (pops->dtps_mode != NULL) {
1209 mode = pops->dtps_mode(prov->dtpv_arg,
1210 probe->dtpr_id, probe->dtpr_arg);
1211
1212 ASSERT((mode & DTRACE_MODE_USER) ||
1213 (mode & DTRACE_MODE_KERNEL));
1214 ASSERT((mode & DTRACE_MODE_NOPRIV_RESTRICT) ||
1215 (mode & DTRACE_MODE_NOPRIV_DROP));
1216 }
1217
1218 /*
1219 * If the dte_cond bits indicate that this consumer is only allowed to
1220 * see user-mode firings of this probe, call the provider's dtps_mode()
1221 * entry point to check that the probe was fired while in a user
1222 * context. If that's not the case, use the policy specified by the
1223 * provider to determine if we drop the probe or merely restrict
1224 * operation.
1225 */
1226 if (ecb->dte_cond & DTRACE_COND_USERMODE) {
1227 ASSERT(mode != DTRACE_MODE_NOPRIV_DROP);
1228
1229 if (!(mode & DTRACE_MODE_USER)) {
1230 if (mode & DTRACE_MODE_NOPRIV_DROP)
1231 return (0);
1232
1233 mstate->dtms_access &= ~DTRACE_ACCESS_ARGS;
1234 }
1235 }
1236
1237 /*
1238 * This is more subtle than it looks. We have to be absolutely certain
1239 * that CRED() isn't going to change out from under us so it's only
1240 * legit to examine that structure if we're in constrained situations.
1241 * Currently, the only times we'll this check is if a non-super-user
1242 * has enabled the profile or syscall providers -- providers that
1243 * allow visibility of all processes. For the profile case, the check
1244 * above will ensure that we're examining a user context.
1245 */
1246 if (ecb->dte_cond & DTRACE_COND_OWNER) {
1247 cred_t *cr;
1248 cred_t *s_cr = state->dts_cred.dcr_cred;
1249 proc_t *proc;
1250
1251 ASSERT(s_cr != NULL);
1252
1253 if ((cr = CRED()) == NULL ||
1254 s_cr->cr_uid != cr->cr_uid ||
1255 s_cr->cr_uid != cr->cr_ruid ||
1256 s_cr->cr_uid != cr->cr_suid ||
1257 s_cr->cr_gid != cr->cr_gid ||
1258 s_cr->cr_gid != cr->cr_rgid ||
1259 s_cr->cr_gid != cr->cr_sgid ||
1260 (proc = ttoproc(curthread)) == NULL ||
1261 (proc->p_flag & SNOCD)) {
1262 if (mode & DTRACE_MODE_NOPRIV_DROP)
1263 return (0);
1264
1265 mstate->dtms_access &= ~DTRACE_ACCESS_PROC;
1266 }
1267 }
1268
1269 /*
1270 * If our dte_cond is set to DTRACE_COND_ZONEOWNER and we are not
1271 * in our zone, check to see if our mode policy is to restrict rather
1272 * than to drop; if to restrict, strip away both DTRACE_ACCESS_PROC
1273 * and DTRACE_ACCESS_ARGS
1274 */
1275 if (ecb->dte_cond & DTRACE_COND_ZONEOWNER) {
1276 cred_t *cr;
1277 cred_t *s_cr = state->dts_cred.dcr_cred;
1278
1279 ASSERT(s_cr != NULL);
1280
1281 if ((cr = CRED()) == NULL ||
1282 s_cr->cr_zone->zone_id != cr->cr_zone->zone_id) {
1283 if (mode & DTRACE_MODE_NOPRIV_DROP)
1284 return (0);
1285
1286 mstate->dtms_access &=
1287 ~(DTRACE_ACCESS_PROC | DTRACE_ACCESS_ARGS);
1288 }
1289 }
1290
1291 return (1);
1292 }
1293
1294 /*
1295 * Note: not called from probe context. This function is called
1296 * asynchronously (and at a regular interval) from outside of probe context to
1297 * clean the dirty dynamic variable lists on all CPUs. Dynamic variable
1298 * cleaning is explained in detail in <sys/dtrace_impl.h>.
1299 */
1300 void
1301 dtrace_dynvar_clean(dtrace_dstate_t *dstate)
1302 {
1303 dtrace_dynvar_t *dirty;
1304 dtrace_dstate_percpu_t *dcpu;
1305 dtrace_dynvar_t **rinsep;
1306 int i, j, work = 0;
1307
1308 for (i = 0; i < NCPU; i++) {
1309 dcpu = &dstate->dtds_percpu[i];
1310 rinsep = &dcpu->dtdsc_rinsing;
1311
1312 /*
1313 * If the dirty list is NULL, there is no dirty work to do.
1314 */
1315 if (dcpu->dtdsc_dirty == NULL)
1316 continue;
1317
1318 if (dcpu->dtdsc_rinsing != NULL) {
1319 /*
1320 * If the rinsing list is non-NULL, then it is because
1321 * this CPU was selected to accept another CPU's
1322 * dirty list -- and since that time, dirty buffers
1323 * have accumulated. This is a highly unlikely
1324 * condition, but we choose to ignore the dirty
1325 * buffers -- they'll be picked up a future cleanse.
1326 */
1327 continue;
1328 }
1329
1330 if (dcpu->dtdsc_clean != NULL) {
1331 /*
1332 * If the clean list is non-NULL, then we're in a
1333 * situation where a CPU has done deallocations (we
1334 * have a non-NULL dirty list) but no allocations (we
1335 * also have a non-NULL clean list). We can't simply
1336 * move the dirty list into the clean list on this
1337 * CPU, yet we also don't want to allow this condition
1338 * to persist, lest a short clean list prevent a
1339 * massive dirty list from being cleaned (which in
1340 * turn could lead to otherwise avoidable dynamic
1341 * drops). To deal with this, we look for some CPU
1342 * with a NULL clean list, NULL dirty list, and NULL
1343 * rinsing list -- and then we borrow this CPU to
1344 * rinse our dirty list.
1345 */
1346 for (j = 0; j < NCPU; j++) {
1347 dtrace_dstate_percpu_t *rinser;
1348
1349 rinser = &dstate->dtds_percpu[j];
1350
1351 if (rinser->dtdsc_rinsing != NULL)
1352 continue;
1353
1354 if (rinser->dtdsc_dirty != NULL)
1355 continue;
1356
1357 if (rinser->dtdsc_clean != NULL)
1358 continue;
1359
1360 rinsep = &rinser->dtdsc_rinsing;
1361 break;
1362 }
1363
1364 if (j == NCPU) {
1365 /*
1366 * We were unable to find another CPU that
1367 * could accept this dirty list -- we are
1368 * therefore unable to clean it now.
1369 */
1370 dtrace_dynvar_failclean++;
1371 continue;
1372 }
1373 }
1374
1375 work = 1;
1376
1377 /*
1378 * Atomically move the dirty list aside.
1379 */
1380 do {
1381 dirty = dcpu->dtdsc_dirty;
1382
1383 /*
1384 * Before we zap the dirty list, set the rinsing list.
1385 * (This allows for a potential assertion in
1386 * dtrace_dynvar(): if a free dynamic variable appears
1387 * on a hash chain, either the dirty list or the
1388 * rinsing list for some CPU must be non-NULL.)
1389 */
1390 *rinsep = dirty;
1391 dtrace_membar_producer();
1392 } while (dtrace_casptr(&dcpu->dtdsc_dirty,
1393 dirty, NULL) != dirty);
1394 }
1395
1396 if (!work) {
1397 /*
1398 * We have no work to do; we can simply return.
1399 */
1400 return;
1401 }
1402
1403 dtrace_sync();
1404
1405 for (i = 0; i < NCPU; i++) {
1406 dcpu = &dstate->dtds_percpu[i];
1407
1408 if (dcpu->dtdsc_rinsing == NULL)
1409 continue;
1410
1411 /*
1412 * We are now guaranteed that no hash chain contains a pointer
1413 * into this dirty list; we can make it clean.
1414 */
1415 ASSERT(dcpu->dtdsc_clean == NULL);
1416 dcpu->dtdsc_clean = dcpu->dtdsc_rinsing;
1417 dcpu->dtdsc_rinsing = NULL;
1418 }
1419
1420 /*
1421 * Before we actually set the state to be DTRACE_DSTATE_CLEAN, make
1422 * sure that all CPUs have seen all of the dtdsc_clean pointers.
1423 * This prevents a race whereby a CPU incorrectly decides that
1424 * the state should be something other than DTRACE_DSTATE_CLEAN
1425 * after dtrace_dynvar_clean() has completed.
1426 */
1427 dtrace_sync();
1428
1429 dstate->dtds_state = DTRACE_DSTATE_CLEAN;
1430 }
1431
1432 /*
1433 * Depending on the value of the op parameter, this function looks-up,
1434 * allocates or deallocates an arbitrarily-keyed dynamic variable. If an
1435 * allocation is requested, this function will return a pointer to a
1436 * dtrace_dynvar_t corresponding to the allocated variable -- or NULL if no
1437 * variable can be allocated. If NULL is returned, the appropriate counter
1438 * will be incremented.
1439 */
1440 dtrace_dynvar_t *
1441 dtrace_dynvar(dtrace_dstate_t *dstate, uint_t nkeys,
1442 dtrace_key_t *key, size_t dsize, dtrace_dynvar_op_t op,
1443 dtrace_mstate_t *mstate, dtrace_vstate_t *vstate)
1444 {
1445 uint64_t hashval = DTRACE_DYNHASH_VALID;
1446 dtrace_dynhash_t *hash = dstate->dtds_hash;
1447 dtrace_dynvar_t *free, *new_free, *next, *dvar, *start, *prev = NULL;
1448 processorid_t me = CPU->cpu_id, cpu = me;
1449 dtrace_dstate_percpu_t *dcpu = &dstate->dtds_percpu[me];
1450 size_t bucket, ksize;
1451 size_t chunksize = dstate->dtds_chunksize;
1452 uintptr_t kdata, lock, nstate;
1453 uint_t i;
1454
1455 ASSERT(nkeys != 0);
1456
1457 /*
1458 * Hash the key. As with aggregations, we use Jenkins' "One-at-a-time"
1459 * algorithm. For the by-value portions, we perform the algorithm in
1460 * 16-bit chunks (as opposed to 8-bit chunks). This speeds things up a
1461 * bit, and seems to have only a minute effect on distribution. For
1462 * the by-reference data, we perform "One-at-a-time" iterating (safely)
1463 * over each referenced byte. It's painful to do this, but it's much
1464 * better than pathological hash distribution. The efficacy of the
1465 * hashing algorithm (and a comparison with other algorithms) may be
1466 * found by running the ::dtrace_dynstat MDB dcmd.
1467 */
1468 for (i = 0; i < nkeys; i++) {
1469 if (key[i].dttk_size == 0) {
1470 uint64_t val = key[i].dttk_value;
1471
1472 hashval += (val >> 48) & 0xffff;
1473 hashval += (hashval << 10);
1474 hashval ^= (hashval >> 6);
1475
1476 hashval += (val >> 32) & 0xffff;
1477 hashval += (hashval << 10);
1478 hashval ^= (hashval >> 6);
1479
1480 hashval += (val >> 16) & 0xffff;
1481 hashval += (hashval << 10);
1482 hashval ^= (hashval >> 6);
1483
1484 hashval += val & 0xffff;
1485 hashval += (hashval << 10);
1486 hashval ^= (hashval >> 6);
1487 } else {
1488 /*
1489 * This is incredibly painful, but it beats the hell
1490 * out of the alternative.
1491 */
1492 uint64_t j, size = key[i].dttk_size;
1493 uintptr_t base = (uintptr_t)key[i].dttk_value;
1494
1495 if (!dtrace_canload(base, size, mstate, vstate))
1496 break;
1497
1498 for (j = 0; j < size; j++) {
1499 hashval += dtrace_load8(base + j);
1500 hashval += (hashval << 10);
1501 hashval ^= (hashval >> 6);
1502 }
1503 }
1504 }
1505
1506 if (DTRACE_CPUFLAG_ISSET(CPU_DTRACE_FAULT))
1507 return (NULL);
1508
1509 hashval += (hashval << 3);
1510 hashval ^= (hashval >> 11);
1511 hashval += (hashval << 15);
1512
1513 /*
1514 * There is a remote chance (ideally, 1 in 2^31) that our hashval
1515 * comes out to be one of our two sentinel hash values. If this
1516 * actually happens, we set the hashval to be a value known to be a
1517 * non-sentinel value.
1518 */
1519 if (hashval == DTRACE_DYNHASH_FREE || hashval == DTRACE_DYNHASH_SINK)
1520 hashval = DTRACE_DYNHASH_VALID;
1521
1522 /*
1523 * Yes, it's painful to do a divide here. If the cycle count becomes
1524 * important here, tricks can be pulled to reduce it. (However, it's
1525 * critical that hash collisions be kept to an absolute minimum;
1526 * they're much more painful than a divide.) It's better to have a
1527 * solution that generates few collisions and still keeps things
1528 * relatively simple.
1529 */
1530 bucket = hashval % dstate->dtds_hashsize;
1531
1532 if (op == DTRACE_DYNVAR_DEALLOC) {
1533 volatile uintptr_t *lockp = &hash[bucket].dtdh_lock;
1534
1535 for (;;) {
1536 while ((lock = *lockp) & 1)
1537 continue;
1538
1539 if (dtrace_casptr((void *)lockp,
1540 (void *)lock, (void *)(lock + 1)) == (void *)lock)
1541 break;
1542 }
1543
1544 dtrace_membar_producer();
1545 }
1546
1547 top:
1548 prev = NULL;
1549 lock = hash[bucket].dtdh_lock;
1550
1551 dtrace_membar_consumer();
1552
1553 start = hash[bucket].dtdh_chain;
1554 ASSERT(start != NULL && (start->dtdv_hashval == DTRACE_DYNHASH_SINK ||
1555 start->dtdv_hashval != DTRACE_DYNHASH_FREE ||
1556 op != DTRACE_DYNVAR_DEALLOC));
1557
1558 for (dvar = start; dvar != NULL; dvar = dvar->dtdv_next) {
1559 dtrace_tuple_t *dtuple = &dvar->dtdv_tuple;
1560 dtrace_key_t *dkey = &dtuple->dtt_key[0];
1561
1562 if (dvar->dtdv_hashval != hashval) {
1563 if (dvar->dtdv_hashval == DTRACE_DYNHASH_SINK) {
1564 /*
1565 * We've reached the sink, and therefore the
1566 * end of the hash chain; we can kick out of
1567 * the loop knowing that we have seen a valid
1568 * snapshot of state.
1569 */
1570 ASSERT(dvar->dtdv_next == NULL);
1571 ASSERT(dvar == &dtrace_dynhash_sink);
1572 break;
1573 }
1574
1575 if (dvar->dtdv_hashval == DTRACE_DYNHASH_FREE) {
1576 /*
1577 * We've gone off the rails: somewhere along
1578 * the line, one of the members of this hash
1579 * chain was deleted. Note that we could also
1580 * detect this by simply letting this loop run
1581 * to completion, as we would eventually hit
1582 * the end of the dirty list. However, we
1583 * want to avoid running the length of the
1584 * dirty list unnecessarily (it might be quite
1585 * long), so we catch this as early as
1586 * possible by detecting the hash marker. In
1587 * this case, we simply set dvar to NULL and
1588 * break; the conditional after the loop will
1589 * send us back to top.
1590 */
1591 dvar = NULL;
1592 break;
1593 }
1594
1595 goto next;
1596 }
1597
1598 if (dtuple->dtt_nkeys != nkeys)
1599 goto next;
1600
1601 for (i = 0; i < nkeys; i++, dkey++) {
1602 if (dkey->dttk_size != key[i].dttk_size)
1603 goto next; /* size or type mismatch */
1604
1605 if (dkey->dttk_size != 0) {
1606 if (dtrace_bcmp(
1607 (void *)(uintptr_t)key[i].dttk_value,
1608 (void *)(uintptr_t)dkey->dttk_value,
1609 dkey->dttk_size))
1610 goto next;
1611 } else {
1612 if (dkey->dttk_value != key[i].dttk_value)
1613 goto next;
1614 }
1615 }
1616
1617 if (op != DTRACE_DYNVAR_DEALLOC)
1618 return (dvar);
1619
1620 ASSERT(dvar->dtdv_next == NULL ||
1621 dvar->dtdv_next->dtdv_hashval != DTRACE_DYNHASH_FREE);
1622
1623 if (prev != NULL) {
1624 ASSERT(hash[bucket].dtdh_chain != dvar);
1625 ASSERT(start != dvar);
1626 ASSERT(prev->dtdv_next == dvar);
1627 prev->dtdv_next = dvar->dtdv_next;
1628 } else {
1629 if (dtrace_casptr(&hash[bucket].dtdh_chain,
1630 start, dvar->dtdv_next) != start) {
1631 /*
1632 * We have failed to atomically swing the
1633 * hash table head pointer, presumably because
1634 * of a conflicting allocation on another CPU.
1635 * We need to reread the hash chain and try
1636 * again.
1637 */
1638 goto top;
1639 }
1640 }
1641
1642 dtrace_membar_producer();
1643
1644 /*
1645 * Now set the hash value to indicate that it's free.
1646 */
1647 ASSERT(hash[bucket].dtdh_chain != dvar);
1648 dvar->dtdv_hashval = DTRACE_DYNHASH_FREE;
1649
1650 dtrace_membar_producer();
1651
1652 /*
1653 * Set the next pointer to point at the dirty list, and
1654 * atomically swing the dirty pointer to the newly freed dvar.
1655 */
1656 do {
1657 next = dcpu->dtdsc_dirty;
1658 dvar->dtdv_next = next;
1659 } while (dtrace_casptr(&dcpu->dtdsc_dirty, next, dvar) != next);
1660
1661 /*
1662 * Finally, unlock this hash bucket.
1663 */
1664 ASSERT(hash[bucket].dtdh_lock == lock);
1665 ASSERT(lock & 1);
1666 hash[bucket].dtdh_lock++;
1667
1668 return (NULL);
1669 next:
1670 prev = dvar;
1671 continue;
1672 }
1673
1674 if (dvar == NULL) {
1675 /*
1676 * If dvar is NULL, it is because we went off the rails:
1677 * one of the elements that we traversed in the hash chain
1678 * was deleted while we were traversing it. In this case,
1679 * we assert that we aren't doing a dealloc (deallocs lock
1680 * the hash bucket to prevent themselves from racing with
1681 * one another), and retry the hash chain traversal.
1682 */
1683 ASSERT(op != DTRACE_DYNVAR_DEALLOC);
1684 goto top;
1685 }
1686
1687 if (op != DTRACE_DYNVAR_ALLOC) {
1688 /*
1689 * If we are not to allocate a new variable, we want to
1690 * return NULL now. Before we return, check that the value
1691 * of the lock word hasn't changed. If it has, we may have
1692 * seen an inconsistent snapshot.
1693 */
1694 if (op == DTRACE_DYNVAR_NOALLOC) {
1695 if (hash[bucket].dtdh_lock != lock)
1696 goto top;
1697 } else {
1698 ASSERT(op == DTRACE_DYNVAR_DEALLOC);
1699 ASSERT(hash[bucket].dtdh_lock == lock);
1700 ASSERT(lock & 1);
1701 hash[bucket].dtdh_lock++;
1702 }
1703
1704 return (NULL);
1705 }
1706
1707 /*
1708 * We need to allocate a new dynamic variable. The size we need is the
1709 * size of dtrace_dynvar plus the size of nkeys dtrace_key_t's plus the
1710 * size of any auxiliary key data (rounded up to 8-byte alignment) plus
1711 * the size of any referred-to data (dsize). We then round the final
1712 * size up to the chunksize for allocation.
1713 */
1714 for (ksize = 0, i = 0; i < nkeys; i++)
1715 ksize += P2ROUNDUP(key[i].dttk_size, sizeof (uint64_t));
1716
1717 /*
1718 * This should be pretty much impossible, but could happen if, say,
1719 * strange DIF specified the tuple. Ideally, this should be an
1720 * assertion and not an error condition -- but that requires that the
1721 * chunksize calculation in dtrace_difo_chunksize() be absolutely
1722 * bullet-proof. (That is, it must not be able to be fooled by
1723 * malicious DIF.) Given the lack of backwards branches in DIF,
1724 * solving this would presumably not amount to solving the Halting
1725 * Problem -- but it still seems awfully hard.
1726 */
1727 if (sizeof (dtrace_dynvar_t) + sizeof (dtrace_key_t) * (nkeys - 1) +
1728 ksize + dsize > chunksize) {
1729 dcpu->dtdsc_drops++;
1730 return (NULL);
1731 }
1732
1733 nstate = DTRACE_DSTATE_EMPTY;
1734
1735 do {
1736 retry:
1737 free = dcpu->dtdsc_free;
1738
1739 if (free == NULL) {
1740 dtrace_dynvar_t *clean = dcpu->dtdsc_clean;
1741 void *rval;
1742
1743 if (clean == NULL) {
1744 /*
1745 * We're out of dynamic variable space on
1746 * this CPU. Unless we have tried all CPUs,
1747 * we'll try to allocate from a different
1748 * CPU.
1749 */
1750 switch (dstate->dtds_state) {
1751 case DTRACE_DSTATE_CLEAN: {
1752 void *sp = &dstate->dtds_state;
1753
1754 if (++cpu >= NCPU)
1755 cpu = 0;
1756
1757 if (dcpu->dtdsc_dirty != NULL &&
1758 nstate == DTRACE_DSTATE_EMPTY)
1759 nstate = DTRACE_DSTATE_DIRTY;
1760
1761 if (dcpu->dtdsc_rinsing != NULL)
1762 nstate = DTRACE_DSTATE_RINSING;
1763
1764 dcpu = &dstate->dtds_percpu[cpu];
1765
1766 if (cpu != me)
1767 goto retry;
1768
1769 (void) dtrace_cas32(sp,
1770 DTRACE_DSTATE_CLEAN, nstate);
1771
1772 /*
1773 * To increment the correct bean
1774 * counter, take another lap.
1775 */
1776 goto retry;
1777 }
1778
1779 case DTRACE_DSTATE_DIRTY:
1780 dcpu->dtdsc_dirty_drops++;
1781 break;
1782
1783 case DTRACE_DSTATE_RINSING:
1784 dcpu->dtdsc_rinsing_drops++;
1785 break;
1786
1787 case DTRACE_DSTATE_EMPTY:
1788 dcpu->dtdsc_drops++;
1789 break;
1790 }
1791
1792 DTRACE_CPUFLAG_SET(CPU_DTRACE_DROP);
1793 return (NULL);
1794 }
1795
1796 /*
1797 * The clean list appears to be non-empty. We want to
1798 * move the clean list to the free list; we start by
1799 * moving the clean pointer aside.
1800 */
1801 if (dtrace_casptr(&dcpu->dtdsc_clean,
1802 clean, NULL) != clean) {
1803 /*
1804 * We are in one of two situations:
1805 *
1806 * (a) The clean list was switched to the
1807 * free list by another CPU.
1808 *
1809 * (b) The clean list was added to by the
1810 * cleansing cyclic.
1811 *
1812 * In either of these situations, we can
1813 * just reattempt the free list allocation.
1814 */
1815 goto retry;
1816 }
1817
1818 ASSERT(clean->dtdv_hashval == DTRACE_DYNHASH_FREE);
1819
1820 /*
1821 * Now we'll move the clean list to our free list.
1822 * It's impossible for this to fail: the only way
1823 * the free list can be updated is through this
1824 * code path, and only one CPU can own the clean list.
1825 * Thus, it would only be possible for this to fail if
1826 * this code were racing with dtrace_dynvar_clean().
1827 * (That is, if dtrace_dynvar_clean() updated the clean
1828 * list, and we ended up racing to update the free
1829 * list.) This race is prevented by the dtrace_sync()
1830 * in dtrace_dynvar_clean() -- which flushes the
1831 * owners of the clean lists out before resetting
1832 * the clean lists.
1833 */
1834 dcpu = &dstate->dtds_percpu[me];
1835 rval = dtrace_casptr(&dcpu->dtdsc_free, NULL, clean);
1836 ASSERT(rval == NULL);
1837 goto retry;
1838 }
1839
1840 dvar = free;
1841 new_free = dvar->dtdv_next;
1842 } while (dtrace_casptr(&dcpu->dtdsc_free, free, new_free) != free);
1843
1844 /*
1845 * We have now allocated a new chunk. We copy the tuple keys into the
1846 * tuple array and copy any referenced key data into the data space
1847 * following the tuple array. As we do this, we relocate dttk_value
1848 * in the final tuple to point to the key data address in the chunk.
1849 */
1850 kdata = (uintptr_t)&dvar->dtdv_tuple.dtt_key[nkeys];
1851 dvar->dtdv_data = (void *)(kdata + ksize);
1852 dvar->dtdv_tuple.dtt_nkeys = nkeys;
1853
1854 for (i = 0; i < nkeys; i++) {
1855 dtrace_key_t *dkey = &dvar->dtdv_tuple.dtt_key[i];
1856 size_t kesize = key[i].dttk_size;
1857
1858 if (kesize != 0) {
1859 dtrace_bcopy(
1860 (const void *)(uintptr_t)key[i].dttk_value,
1861 (void *)kdata, kesize);
1862 dkey->dttk_value = kdata;
1863 kdata += P2ROUNDUP(kesize, sizeof (uint64_t));
1864 } else {
1865 dkey->dttk_value = key[i].dttk_value;
1866 }
1867
1868 dkey->dttk_size = kesize;
1869 }
1870
1871 ASSERT(dvar->dtdv_hashval == DTRACE_DYNHASH_FREE);
1872 dvar->dtdv_hashval = hashval;
1873 dvar->dtdv_next = start;
1874
1875 if (dtrace_casptr(&hash[bucket].dtdh_chain, start, dvar) == start)
1876 return (dvar);
1877
1878 /*
1879 * The cas has failed. Either another CPU is adding an element to
1880 * this hash chain, or another CPU is deleting an element from this
1881 * hash chain. The simplest way to deal with both of these cases
1882 * (though not necessarily the most efficient) is to free our
1883 * allocated block and tail-call ourselves. Note that the free is
1884 * to the dirty list and _not_ to the free list. This is to prevent
1885 * races with allocators, above.
1886 */
1887 dvar->dtdv_hashval = DTRACE_DYNHASH_FREE;
1888
1889 dtrace_membar_producer();
1890
1891 do {
1892 free = dcpu->dtdsc_dirty;
1893 dvar->dtdv_next = free;
1894 } while (dtrace_casptr(&dcpu->dtdsc_dirty, free, dvar) != free);
1895
1896 return (dtrace_dynvar(dstate, nkeys, key, dsize, op, mstate, vstate));
1897 }
1898
1899 /*ARGSUSED*/
1900 static void
1901 dtrace_aggregate_min(uint64_t *oval, uint64_t nval, uint64_t arg)
1902 {
1903 if ((int64_t)nval < (int64_t)*oval)
1904 *oval = nval;
1905 }
1906
1907 /*ARGSUSED*/
1908 static void
1909 dtrace_aggregate_max(uint64_t *oval, uint64_t nval, uint64_t arg)
1910 {
1911 if ((int64_t)nval > (int64_t)*oval)
1912 *oval = nval;
1913 }
1914
1915 static void
1916 dtrace_aggregate_quantize(uint64_t *quanta, uint64_t nval, uint64_t incr)
1917 {
1918 int i, zero = DTRACE_QUANTIZE_ZEROBUCKET;
1919 int64_t val = (int64_t)nval;
1920
1921 if (val < 0) {
1922 for (i = 0; i < zero; i++) {
1923 if (val <= DTRACE_QUANTIZE_BUCKETVAL(i)) {
1924 quanta[i] += incr;
1925 return;
1926 }
1927 }
1928 } else {
1929 for (i = zero + 1; i < DTRACE_QUANTIZE_NBUCKETS; i++) {
1930 if (val < DTRACE_QUANTIZE_BUCKETVAL(i)) {
1931 quanta[i - 1] += incr;
1932 return;
1933 }
1934 }
1935
1936 quanta[DTRACE_QUANTIZE_NBUCKETS - 1] += incr;
1937 return;
1938 }
1939
1940 ASSERT(0);
1941 }
1942
1943 static void
1944 dtrace_aggregate_lquantize(uint64_t *lquanta, uint64_t nval, uint64_t incr)
1945 {
1946 uint64_t arg = *lquanta++;
1947 int32_t base = DTRACE_LQUANTIZE_BASE(arg);
1948 uint16_t step = DTRACE_LQUANTIZE_STEP(arg);
1949 uint16_t levels = DTRACE_LQUANTIZE_LEVELS(arg);
1950 int32_t val = (int32_t)nval, level;
1951
1952 ASSERT(step != 0);
1953 ASSERT(levels != 0);
1954
1955 if (val < base) {
1956 /*
1957 * This is an underflow.
1958 */
1959 lquanta[0] += incr;
1960 return;
1961 }
1962
1963 level = (val - base) / step;
1964
1965 if (level < levels) {
1966 lquanta[level + 1] += incr;
1967 return;
1968 }
1969
1970 /*
1971 * This is an overflow.
1972 */
1973 lquanta[levels + 1] += incr;
1974 }
1975
1976 static int
1977 dtrace_aggregate_llquantize_bucket(uint16_t factor, uint16_t low,
1978 uint16_t high, uint16_t nsteps, int64_t value)
1979 {
1980 int64_t this = 1, last, next;
1981 int base = 1, order;
1982
1983 ASSERT(factor <= nsteps);
1984 ASSERT(nsteps % factor == 0);
1985
1986 for (order = 0; order < low; order++)
1987 this *= factor;
1988
1989 /*
1990 * If our value is less than our factor taken to the power of the
1991 * low order of magnitude, it goes into the zeroth bucket.
1992 */
1993 if (value < (last = this))
1994 return (0);
1995
1996 for (this *= factor; order <= high; order++) {
1997 int nbuckets = this > nsteps ? nsteps : this;
1998
1999 if ((next = this * factor) < this) {
2000 /*
2001 * We should not generally get log/linear quantizations
2002 * with a high magnitude that allows 64-bits to
2003 * overflow, but we nonetheless protect against this
2004 * by explicitly checking for overflow, and clamping
2005 * our value accordingly.
2006 */
2007 value = this - 1;
2008 }
2009
2010 if (value < this) {
2011 /*
2012 * If our value lies within this order of magnitude,
2013 * determine its position by taking the offset within
2014 * the order of magnitude, dividing by the bucket
2015 * width, and adding to our (accumulated) base.
2016 */
2017 return (base + (value - last) / (this / nbuckets));
2018 }
2019
2020 base += nbuckets - (nbuckets / factor);
2021 last = this;
2022 this = next;
2023 }
2024
2025 /*
2026 * Our value is greater than or equal to our factor taken to the
2027 * power of one plus the high magnitude -- return the top bucket.
2028 */
2029 return (base);
2030 }
2031
2032 static void
2033 dtrace_aggregate_llquantize(uint64_t *llquanta, uint64_t nval, uint64_t incr)
2034 {
2035 uint64_t arg = *llquanta++;
2036 uint16_t factor = DTRACE_LLQUANTIZE_FACTOR(arg);
2037 uint16_t low = DTRACE_LLQUANTIZE_LOW(arg);
2038 uint16_t high = DTRACE_LLQUANTIZE_HIGH(arg);
2039 uint16_t nsteps = DTRACE_LLQUANTIZE_NSTEP(arg);
2040
2041 llquanta[dtrace_aggregate_llquantize_bucket(factor,
2042 low, high, nsteps, nval)] += incr;
2043 }
2044
2045 /*ARGSUSED*/
2046 static void
2047 dtrace_aggregate_avg(uint64_t *data, uint64_t nval, uint64_t arg)
2048 {
2049 data[0]++;
2050 data[1] += nval;
2051 }
2052
2053 /*ARGSUSED*/
2054 static void
2055 dtrace_aggregate_stddev(uint64_t *data, uint64_t nval, uint64_t arg)
2056 {
2057 int64_t snval = (int64_t)nval;
2058 uint64_t tmp[2];
2059
2060 data[0]++;
2061 data[1] += nval;
2062
2063 /*
2064 * What we want to say here is:
2065 *
2066 * data[2] += nval * nval;
2067 *
2068 * But given that nval is 64-bit, we could easily overflow, so
2069 * we do this as 128-bit arithmetic.
2070 */
2071 if (snval < 0)
2072 snval = -snval;
2073
2074 dtrace_multiply_128((uint64_t)snval, (uint64_t)snval, tmp);
2075 dtrace_add_128(data + 2, tmp, data + 2);
2076 }
2077
2078 /*ARGSUSED*/
2079 static void
2080 dtrace_aggregate_count(uint64_t *oval, uint64_t nval, uint64_t arg)
2081 {
2082 *oval = *oval + 1;
2083 }
2084
2085 /*ARGSUSED*/
2086 static void
2087 dtrace_aggregate_sum(uint64_t *oval, uint64_t nval, uint64_t arg)
2088 {
2089 *oval += nval;
2090 }
2091
2092 /*
2093 * Aggregate given the tuple in the principal data buffer, and the aggregating
2094 * action denoted by the specified dtrace_aggregation_t. The aggregation
2095 * buffer is specified as the buf parameter. This routine does not return
2096 * failure; if there is no space in the aggregation buffer, the data will be
2097 * dropped, and a corresponding counter incremented.
2098 */
2099 static void
2100 dtrace_aggregate(dtrace_aggregation_t *agg, dtrace_buffer_t *dbuf,
2101 intptr_t offset, dtrace_buffer_t *buf, uint64_t expr, uint64_t arg)
2102 {
2103 dtrace_recdesc_t *rec = &agg->dtag_action.dta_rec;
2104 uint32_t i, ndx, size, fsize;
2105 uint32_t align = sizeof (uint64_t) - 1;
2106 dtrace_aggbuffer_t *agb;
2107 dtrace_aggkey_t *key;
2108 uint32_t hashval = 0, limit, isstr;
2109 caddr_t tomax, data, kdata;
2110 dtrace_actkind_t action;
2111 dtrace_action_t *act;
2112 uintptr_t offs;
2113
2114 if (buf == NULL)
2115 return;
2116
2117 if (!agg->dtag_hasarg) {
2118 /*
2119 * Currently, only quantize() and lquantize() take additional
2120 * arguments, and they have the same semantics: an increment
2121 * value that defaults to 1 when not present. If additional
2122 * aggregating actions take arguments, the setting of the
2123 * default argument value will presumably have to become more
2124 * sophisticated...
2125 */
2126 arg = 1;
2127 }
2128
2129 action = agg->dtag_action.dta_kind - DTRACEACT_AGGREGATION;
2130 size = rec->dtrd_offset - agg->dtag_base;
2131 fsize = size + rec->dtrd_size;
2132
2133 ASSERT(dbuf->dtb_tomax != NULL);
2134 data = dbuf->dtb_tomax + offset + agg->dtag_base;
2135
2136 if ((tomax = buf->dtb_tomax) == NULL) {
2137 dtrace_buffer_drop(buf);
2138 return;
2139 }
2140
2141 /*
2142 * The metastructure is always at the bottom of the buffer.
2143 */
2144 agb = (dtrace_aggbuffer_t *)(tomax + buf->dtb_size -
2145 sizeof (dtrace_aggbuffer_t));
2146
2147 if (buf->dtb_offset == 0) {
2148 /*
2149 * We just kludge up approximately 1/8th of the size to be
2150 * buckets. If this guess ends up being routinely
2151 * off-the-mark, we may need to dynamically readjust this
2152 * based on past performance.
2153 */
2154 uintptr_t hashsize = (buf->dtb_size >> 3) / sizeof (uintptr_t);
2155
2156 if ((uintptr_t)agb - hashsize * sizeof (dtrace_aggkey_t *) <
2157 (uintptr_t)tomax || hashsize == 0) {
2158 /*
2159 * We've been given a ludicrously small buffer;
2160 * increment our drop count and leave.
2161 */
2162 dtrace_buffer_drop(buf);
2163 return;
2164 }
2165
2166 /*
2167 * And now, a pathetic attempt to try to get a an odd (or
2168 * perchance, a prime) hash size for better hash distribution.
2169 */
2170 if (hashsize > (DTRACE_AGGHASHSIZE_SLEW << 3))
2171 hashsize -= DTRACE_AGGHASHSIZE_SLEW;
2172
2173 agb->dtagb_hashsize = hashsize;
2174 agb->dtagb_hash = (dtrace_aggkey_t **)((uintptr_t)agb -
2175 agb->dtagb_hashsize * sizeof (dtrace_aggkey_t *));
2176 agb->dtagb_free = (uintptr_t)agb->dtagb_hash;
2177
2178 for (i = 0; i < agb->dtagb_hashsize; i++)
2179 agb->dtagb_hash[i] = NULL;
2180 }
2181
2182 ASSERT(agg->dtag_first != NULL);
2183 ASSERT(agg->dtag_first->dta_intuple);
2184
2185 /*
2186 * Calculate the hash value based on the key. Note that we _don't_
2187 * include the aggid in the hashing (but we will store it as part of
2188 * the key). The hashing algorithm is Bob Jenkins' "One-at-a-time"
2189 * algorithm: a simple, quick algorithm that has no known funnels, and
2190 * gets good distribution in practice. The efficacy of the hashing
2191 * algorithm (and a comparison with other algorithms) may be found by
2192 * running the ::dtrace_aggstat MDB dcmd.
2193 */
2194 for (act = agg->dtag_first; act->dta_intuple; act = act->dta_next) {
2195 i = act->dta_rec.dtrd_offset - agg->dtag_base;
2196 limit = i + act->dta_rec.dtrd_size;
2197 ASSERT(limit <= size);
2198 isstr = DTRACEACT_ISSTRING(act);
2199
2200 for (; i < limit; i++) {
2201 hashval += data[i];
2202 hashval += (hashval << 10);
2203 hashval ^= (hashval >> 6);
2204
2205 if (isstr && data[i] == '\0')
2206 break;
2207 }
2208 }
2209
2210 hashval += (hashval << 3);
2211 hashval ^= (hashval >> 11);
2212 hashval += (hashval << 15);
2213
2214 /*
2215 * Yes, the divide here is expensive -- but it's generally the least
2216 * of the performance issues given the amount of data that we iterate
2217 * over to compute hash values, compare data, etc.
2218 */
2219 ndx = hashval % agb->dtagb_hashsize;
2220
2221 for (key = agb->dtagb_hash[ndx]; key != NULL; key = key->dtak_next) {
2222 ASSERT((caddr_t)key >= tomax);
2223 ASSERT((caddr_t)key < tomax + buf->dtb_size);
2224
2225 if (hashval != key->dtak_hashval || key->dtak_size != size)
2226 continue;
2227
2228 kdata = key->dtak_data;
2229 ASSERT(kdata >= tomax && kdata < tomax + buf->dtb_size);
2230
2231 for (act = agg->dtag_first; act->dta_intuple;
2232 act = act->dta_next) {
2233 i = act->dta_rec.dtrd_offset - agg->dtag_base;
2234 limit = i + act->dta_rec.dtrd_size;
2235 ASSERT(limit <= size);
2236 isstr = DTRACEACT_ISSTRING(act);
2237
2238 for (; i < limit; i++) {
2239 if (kdata[i] != data[i])
2240 goto next;
2241
2242 if (isstr && data[i] == '\0')
2243 break;
2244 }
2245 }
2246
2247 if (action != key->dtak_action) {
2248 /*
2249 * We are aggregating on the same value in the same
2250 * aggregation with two different aggregating actions.
2251 * (This should have been picked up in the compiler,
2252 * so we may be dealing with errant or devious DIF.)
2253 * This is an error condition; we indicate as much,
2254 * and return.
2255 */
2256 DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP);
2257 return;
2258 }
2259
2260 /*
2261 * This is a hit: we need to apply the aggregator to
2262 * the value at this key.
2263 */
2264 agg->dtag_aggregate((uint64_t *)(kdata + size), expr, arg);
2265 return;
2266 next:
2267 continue;
2268 }
2269
2270 /*
2271 * We didn't find it. We need to allocate some zero-filled space,
2272 * link it into the hash table appropriately, and apply the aggregator
2273 * to the (zero-filled) value.
2274 */
2275 offs = buf->dtb_offset;
2276 while (offs & (align - 1))
2277 offs += sizeof (uint32_t);
2278
2279 /*
2280 * If we don't have enough room to both allocate a new key _and_
2281 * its associated data, increment the drop count and return.
2282 */
2283 if ((uintptr_t)tomax + offs + fsize >
2284 agb->dtagb_free - sizeof (dtrace_aggkey_t)) {
2285 dtrace_buffer_drop(buf);
2286 return;
2287 }
2288
2289 /*CONSTCOND*/
2290 ASSERT(!(sizeof (dtrace_aggkey_t) & (sizeof (uintptr_t) - 1)));
2291 key = (dtrace_aggkey_t *)(agb->dtagb_free - sizeof (dtrace_aggkey_t));
2292 agb->dtagb_free -= sizeof (dtrace_aggkey_t);
2293
2294 key->dtak_data = kdata = tomax + offs;
2295 buf->dtb_offset = offs + fsize;
2296
2297 /*
2298 * Now copy the data across.
2299 */
2300 *((dtrace_aggid_t *)kdata) = agg->dtag_id;
2301
2302 for (i = sizeof (dtrace_aggid_t); i < size; i++)
2303 kdata[i] = data[i];
2304
2305 /*
2306 * Because strings are not zeroed out by default, we need to iterate
2307 * looking for actions that store strings, and we need to explicitly
2308 * pad these strings out with zeroes.
2309 */
2310 for (act = agg->dtag_first; act->dta_intuple; act = act->dta_next) {
2311 int nul;
2312
2313 if (!DTRACEACT_ISSTRING(act))
2314 continue;
2315
2316 i = act->dta_rec.dtrd_offset - agg->dtag_base;
2317 limit = i + act->dta_rec.dtrd_size;
2318 ASSERT(limit <= size);
2319
2320 for (nul = 0; i < limit; i++) {
2321 if (nul) {
2322 kdata[i] = '\0';
2323 continue;
2324 }
2325
2326 if (data[i] != '\0')
2327 continue;
2328
2329 nul = 1;
2330 }
2331 }
2332
2333 for (i = size; i < fsize; i++)
2334 kdata[i] = 0;
2335
2336 key->dtak_hashval = hashval;
2337 key->dtak_size = size;
2338 key->dtak_action = action;
2339 key->dtak_next = agb->dtagb_hash[ndx];
2340 agb->dtagb_hash[ndx] = key;
2341
2342 /*
2343 * Finally, apply the aggregator.
2344 */
2345 *((uint64_t *)(key->dtak_data + size)) = agg->dtag_initial;
2346 agg->dtag_aggregate((uint64_t *)(key->dtak_data + size), expr, arg);
2347 }
2348
2349 /*
2350 * Given consumer state, this routine finds a speculation in the INACTIVE
2351 * state and transitions it into the ACTIVE state. If there is no speculation
2352 * in the INACTIVE state, 0 is returned. In this case, no error counter is
2353 * incremented -- it is up to the caller to take appropriate action.
2354 */
2355 static int
2356 dtrace_speculation(dtrace_state_t *state)
2357 {
2358 int i = 0;
2359 dtrace_speculation_state_t current;
2360 uint32_t *stat = &state->dts_speculations_unavail, count;
2361
2362 while (i < state->dts_nspeculations) {
2363 dtrace_speculation_t *spec = &state->dts_speculations[i];
2364
2365 current = spec->dtsp_state;
2366
2367 if (current != DTRACESPEC_INACTIVE) {
2368 if (current == DTRACESPEC_COMMITTINGMANY ||
2369 current == DTRACESPEC_COMMITTING ||
2370 current == DTRACESPEC_DISCARDING)
2371 stat = &state->dts_speculations_busy;
2372 i++;
2373 continue;
2374 }
2375
2376 if (dtrace_cas32((uint32_t *)&spec->dtsp_state,
2377 current, DTRACESPEC_ACTIVE) == current)
2378 return (i + 1);
2379 }
2380
2381 /*
2382 * We couldn't find a speculation. If we found as much as a single
2383 * busy speculation buffer, we'll attribute this failure as "busy"
2384 * instead of "unavail".
2385 */
2386 do {
2387 count = *stat;
2388 } while (dtrace_cas32(stat, count, count + 1) != count);
2389
2390 return (0);
2391 }
2392
2393 /*
2394 * This routine commits an active speculation. If the specified speculation
2395 * is not in a valid state to perform a commit(), this routine will silently do
2396 * nothing. The state of the specified speculation is transitioned according
2397 * to the state transition diagram outlined in <sys/dtrace_impl.h>
2398 */
2399 static void
2400 dtrace_speculation_commit(dtrace_state_t *state, processorid_t cpu,
2401 dtrace_specid_t which)
2402 {
2403 dtrace_speculation_t *spec;
2404 dtrace_buffer_t *src, *dest;
2405 uintptr_t daddr, saddr, dlimit, slimit;
2406 dtrace_speculation_state_t current, new;
2407 intptr_t offs;
2408 uint64_t timestamp;
2409
2410 if (which == 0)
2411 return;
2412
2413 if (which > state->dts_nspeculations) {
2414 cpu_core[cpu].cpuc_dtrace_flags |= CPU_DTRACE_ILLOP;
2415 return;
2416 }
2417
2418 spec = &state->dts_speculations[which - 1];
2419 src = &spec->dtsp_buffer[cpu];
2420 dest = &state->dts_buffer[cpu];
2421
2422 do {
2423 current = spec->dtsp_state;
2424
2425 if (current == DTRACESPEC_COMMITTINGMANY)
2426 break;
2427
2428 switch (current) {
2429 case DTRACESPEC_INACTIVE:
2430 case DTRACESPEC_DISCARDING:
2431 return;
2432
2433 case DTRACESPEC_COMMITTING:
2434 /*
2435 * This is only possible if we are (a) commit()'ing
2436 * without having done a prior speculate() on this CPU
2437 * and (b) racing with another commit() on a different
2438 * CPU. There's nothing to do -- we just assert that
2439 * our offset is 0.
2440 */
2441 ASSERT(src->dtb_offset == 0);
2442 return;
2443
2444 case DTRACESPEC_ACTIVE:
2445 new = DTRACESPEC_COMMITTING;
2446 break;
2447
2448 case DTRACESPEC_ACTIVEONE:
2449 /*
2450 * This speculation is active on one CPU. If our
2451 * buffer offset is non-zero, we know that the one CPU
2452 * must be us. Otherwise, we are committing on a
2453 * different CPU from the speculate(), and we must
2454 * rely on being asynchronously cleaned.
2455 */
2456 if (src->dtb_offset != 0) {
2457 new = DTRACESPEC_COMMITTING;
2458 break;
2459 }
2460 /*FALLTHROUGH*/
2461
2462 case DTRACESPEC_ACTIVEMANY:
2463 new = DTRACESPEC_COMMITTINGMANY;
2464 break;
2465
2466 default:
2467 ASSERT(0);
2468 }
2469 } while (dtrace_cas32((uint32_t *)&spec->dtsp_state,
2470 current, new) != current);
2471
2472 /*
2473 * We have set the state to indicate that we are committing this
2474 * speculation. Now reserve the necessary space in the destination
2475 * buffer.
2476 */
2477 if ((offs = dtrace_buffer_reserve(dest, src->dtb_offset,
2478 sizeof (uint64_t), state, NULL)) < 0) {
2479 dtrace_buffer_drop(dest);
2480 goto out;
2481 }
2482
2483 /*
2484 * We have sufficient space to copy the speculative buffer into the
2485 * primary buffer. First, modify the speculative buffer, filling
2486 * in the timestamp of all entries with the current time. The data
2487 * must have the commit() time rather than the time it was traced,
2488 * so that all entries in the primary buffer are in timestamp order.
2489 */
2490 timestamp = dtrace_gethrtime();
2491 saddr = (uintptr_t)src->dtb_tomax;
2492 slimit = saddr + src->dtb_offset;
2493 while (saddr < slimit) {
2494 size_t size;
2495 dtrace_rechdr_t *dtrh = (dtrace_rechdr_t *)saddr;
2496
2497 if (dtrh->dtrh_epid == DTRACE_EPIDNONE) {
2498 saddr += sizeof (dtrace_epid_t);
2499 continue;
2500 }
2501 ASSERT3U(dtrh->dtrh_epid, <=, state->dts_necbs);
2502 size = state->dts_ecbs[dtrh->dtrh_epid - 1]->dte_size;
2503
2504 ASSERT3U(saddr + size, <=, slimit);
2505 ASSERT3U(size, >=, sizeof (dtrace_rechdr_t));
2506 ASSERT3U(DTRACE_RECORD_LOAD_TIMESTAMP(dtrh), ==, UINT64_MAX);
2507
2508 DTRACE_RECORD_STORE_TIMESTAMP(dtrh, timestamp);
2509
2510 saddr += size;
2511 }
2512
2513 /*
2514 * Copy the buffer across. (Note that this is a
2515 * highly subobtimal bcopy(); in the unlikely event that this becomes
2516 * a serious performance issue, a high-performance DTrace-specific
2517 * bcopy() should obviously be invented.)
2518 */
2519 daddr = (uintptr_t)dest->dtb_tomax + offs;
2520 dlimit = daddr + src->dtb_offset;
2521 saddr = (uintptr_t)src->dtb_tomax;
2522
2523 /*
2524 * First, the aligned portion.
2525 */
2526 while (dlimit - daddr >= sizeof (uint64_t)) {
2527 *((uint64_t *)daddr) = *((uint64_t *)saddr);
2528
2529 daddr += sizeof (uint64_t);
2530 saddr += sizeof (uint64_t);
2531 }
2532
2533 /*
2534 * Now any left-over bit...
2535 */
2536 while (dlimit - daddr)
2537 *((uint8_t *)daddr++) = *((uint8_t *)saddr++);
2538
2539 /*
2540 * Finally, commit the reserved space in the destination buffer.
2541 */
2542 dest->dtb_offset = offs + src->dtb_offset;
2543
2544 out:
2545 /*
2546 * If we're lucky enough to be the only active CPU on this speculation
2547 * buffer, we can just set the state back to DTRACESPEC_INACTIVE.
2548 */
2549 if (current == DTRACESPEC_ACTIVE ||
2550 (current == DTRACESPEC_ACTIVEONE && new == DTRACESPEC_COMMITTING)) {
2551 uint32_t rval = dtrace_cas32((uint32_t *)&spec->dtsp_state,
2552 DTRACESPEC_COMMITTING, DTRACESPEC_INACTIVE);
2553
2554 ASSERT(rval == DTRACESPEC_COMMITTING);
2555 }
2556
2557 src->dtb_offset = 0;
2558 src->dtb_xamot_drops += src->dtb_drops;
2559 src->dtb_drops = 0;
2560 }
2561
2562 /*
2563 * This routine discards an active speculation. If the specified speculation
2564 * is not in a valid state to perform a discard(), this routine will silently
2565 * do nothing. The state of the specified speculation is transitioned
2566 * according to the state transition diagram outlined in <sys/dtrace_impl.h>
2567 */
2568 static void
2569 dtrace_speculation_discard(dtrace_state_t *state, processorid_t cpu,
2570 dtrace_specid_t which)
2571 {
2572 dtrace_speculation_t *spec;
2573 dtrace_speculation_state_t current, new;
2574 dtrace_buffer_t *buf;
2575
2576 if (which == 0)
2577 return;
2578
2579 if (which > state->dts_nspeculations) {
2580 cpu_core[cpu].cpuc_dtrace_flags |= CPU_DTRACE_ILLOP;
2581 return;
2582 }
2583
2584 spec = &state->dts_speculations[which - 1];
2585 buf = &spec->dtsp_buffer[cpu];
2586
2587 do {
2588 current = spec->dtsp_state;
2589
2590 switch (current) {
2591 case DTRACESPEC_INACTIVE:
2592 case DTRACESPEC_COMMITTINGMANY:
2593 case DTRACESPEC_COMMITTING:
2594 case DTRACESPEC_DISCARDING:
2595 return;
2596
2597 case DTRACESPEC_ACTIVE:
2598 case DTRACESPEC_ACTIVEMANY:
2599 new = DTRACESPEC_DISCARDING;
2600 break;
2601
2602 case DTRACESPEC_ACTIVEONE:
2603 if (buf->dtb_offset != 0) {
2604 new = DTRACESPEC_INACTIVE;
2605 } else {
2606 new = DTRACESPEC_DISCARDING;
2607 }
2608 break;
2609
2610 default:
2611 ASSERT(0);
2612 }
2613 } while (dtrace_cas32((uint32_t *)&spec->dtsp_state,
2614 current, new) != current);
2615
2616 buf->dtb_offset = 0;
2617 buf->dtb_drops = 0;
2618 }
2619
2620 /*
2621 * Note: not called from probe context. This function is called
2622 * asynchronously from cross call context to clean any speculations that are
2623 * in the COMMITTINGMANY or DISCARDING states. These speculations may not be
2624 * transitioned back to the INACTIVE state until all CPUs have cleaned the
2625 * speculation.
2626 */
2627 static void
2628 dtrace_speculation_clean_here(dtrace_state_t *state)
2629 {
2630 dtrace_icookie_t cookie;
2631 processorid_t cpu = CPU->cpu_id;
2632 dtrace_buffer_t *dest = &state->dts_buffer[cpu];
2633 dtrace_specid_t i;
2634
2635 cookie = dtrace_interrupt_disable();
2636
2637 if (dest->dtb_tomax == NULL) {
2638 dtrace_interrupt_enable(cookie);
2639 return;
2640 }
2641
2642 for (i = 0; i < state->dts_nspeculations; i++) {
2643 dtrace_speculation_t *spec = &state->dts_speculations[i];
2644 dtrace_buffer_t *src = &spec->dtsp_buffer[cpu];
2645
2646 if (src->dtb_tomax == NULL)
2647 continue;
2648
2649 if (spec->dtsp_state == DTRACESPEC_DISCARDING) {
2650 src->dtb_offset = 0;
2651 continue;
2652 }
2653
2654 if (spec->dtsp_state != DTRACESPEC_COMMITTINGMANY)
2655 continue;
2656
2657 if (src->dtb_offset == 0)
2658 continue;
2659
2660 dtrace_speculation_commit(state, cpu, i + 1);
2661 }
2662
2663 dtrace_interrupt_enable(cookie);
2664 }
2665
2666 /*
2667 * Note: not called from probe context. This function is called
2668 * asynchronously (and at a regular interval) to clean any speculations that
2669 * are in the COMMITTINGMANY or DISCARDING states. If it discovers that there
2670 * is work to be done, it cross calls all CPUs to perform that work;
2671 * COMMITMANY and DISCARDING speculations may not be transitioned back to the
2672 * INACTIVE state until they have been cleaned by all CPUs.
2673 */
2674 static void
2675 dtrace_speculation_clean(dtrace_state_t *state)
2676 {
2677 int work = 0, rv;
2678 dtrace_specid_t i;
2679
2680 for (i = 0; i < state->dts_nspeculations; i++) {
2681 dtrace_speculation_t *spec = &state->dts_speculations[i];
2682
2683 ASSERT(!spec->dtsp_cleaning);
2684
2685 if (spec->dtsp_state != DTRACESPEC_DISCARDING &&
2686 spec->dtsp_state != DTRACESPEC_COMMITTINGMANY)
2687 continue;
2688
2689 work++;
2690 spec->dtsp_cleaning = 1;
2691 }
2692
2693 if (!work)
2694 return;
2695
2696 dtrace_xcall(DTRACE_CPUALL,
2697 (dtrace_xcall_t)dtrace_speculation_clean_here, state);
2698
2699 /*
2700 * We now know that all CPUs have committed or discarded their
2701 * speculation buffers, as appropriate. We can now set the state
2702 * to inactive.
2703 */
2704 for (i = 0; i < state->dts_nspeculations; i++) {
2705 dtrace_speculation_t *spec = &state->dts_speculations[i];
2706 dtrace_speculation_state_t current, new;
2707
2708 if (!spec->dtsp_cleaning)
2709 continue;
2710
2711 current = spec->dtsp_state;
2712 ASSERT(current == DTRACESPEC_DISCARDING ||
2713 current == DTRACESPEC_COMMITTINGMANY);
2714
2715 new = DTRACESPEC_INACTIVE;
2716
2717 rv = dtrace_cas32((uint32_t *)&spec->dtsp_state, current, new);
2718 ASSERT(rv == current);
2719 spec->dtsp_cleaning = 0;
2720 }
2721 }
2722
2723 /*
2724 * Called as part of a speculate() to get the speculative buffer associated
2725 * with a given speculation. Returns NULL if the specified speculation is not
2726 * in an ACTIVE state. If the speculation is in the ACTIVEONE state -- and
2727 * the active CPU is not the specified CPU -- the speculation will be
2728 * atomically transitioned into the ACTIVEMANY state.
2729 */
2730 static dtrace_buffer_t *
2731 dtrace_speculation_buffer(dtrace_state_t *state, processorid_t cpuid,
2732 dtrace_specid_t which)
2733 {
2734 dtrace_speculation_t *spec;
2735 dtrace_speculation_state_t current, new;
2736 dtrace_buffer_t *buf;
2737
2738 if (which == 0)
2739 return (NULL);
2740
2741 if (which > state->dts_nspeculations) {
2742 cpu_core[cpuid].cpuc_dtrace_flags |= CPU_DTRACE_ILLOP;
2743 return (NULL);
2744 }
2745
2746 spec = &state->dts_speculations[which - 1];
2747 buf = &spec->dtsp_buffer[cpuid];
2748
2749 do {
2750 current = spec->dtsp_state;
2751
2752 switch (current) {
2753 case DTRACESPEC_INACTIVE:
2754 case DTRACESPEC_COMMITTINGMANY:
2755 case DTRACESPEC_DISCARDING:
2756 return (NULL);
2757
2758 case DTRACESPEC_COMMITTING:
2759 ASSERT(buf->dtb_offset == 0);
2760 return (NULL);
2761
2762 case DTRACESPEC_ACTIVEONE:
2763 /*
2764 * This speculation is currently active on one CPU.
2765 * Check the offset in the buffer; if it's non-zero,
2766 * that CPU must be us (and we leave the state alone).
2767 * If it's zero, assume that we're starting on a new
2768 * CPU -- and change the state to indicate that the
2769 * speculation is active on more than one CPU.
2770 */
2771 if (buf->dtb_offset != 0)
2772 return (buf);
2773
2774 new = DTRACESPEC_ACTIVEMANY;
2775 break;
2776
2777 case DTRACESPEC_ACTIVEMANY:
2778 return (buf);
2779
2780 case DTRACESPEC_ACTIVE:
2781 new = DTRACESPEC_ACTIVEONE;
2782 break;
2783
2784 default:
2785 ASSERT(0);
2786 }
2787 } while (dtrace_cas32((uint32_t *)&spec->dtsp_state,
2788 current, new) != current);
2789
2790 ASSERT(new == DTRACESPEC_ACTIVEONE || new == DTRACESPEC_ACTIVEMANY);
2791 return (buf);
2792 }
2793
2794 /*
2795 * Return a string. In the event that the user lacks the privilege to access
2796 * arbitrary kernel memory, we copy the string out to scratch memory so that we
2797 * don't fail access checking.
2798 *
2799 * dtrace_dif_variable() uses this routine as a helper for various
2800 * builtin values such as 'execname' and 'probefunc.'
2801 */
2802 uintptr_t
2803 dtrace_dif_varstr(uintptr_t addr, dtrace_state_t *state,
2804 dtrace_mstate_t *mstate)
2805 {
2806 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
2807 uintptr_t ret;
2808 size_t strsz;
2809
2810 /*
2811 * The easy case: this probe is allowed to read all of memory, so
2812 * we can just return this as a vanilla pointer.
2813 */
2814 if ((mstate->dtms_access & DTRACE_ACCESS_KERNEL) != 0)
2815 return (addr);
2816
2817 /*
2818 * This is the tougher case: we copy the string in question from
2819 * kernel memory into scratch memory and return it that way: this
2820 * ensures that we won't trip up when access checking tests the
2821 * BYREF return value.
2822 */
2823 strsz = dtrace_strlen((char *)addr, size) + 1;
2824
2825 if (mstate->dtms_scratch_ptr + strsz >
2826 mstate->dtms_scratch_base + mstate->dtms_scratch_size) {
2827 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
2828 return (NULL);
2829 }
2830
2831 dtrace_strcpy((const void *)addr, (void *)mstate->dtms_scratch_ptr,
2832 strsz);
2833 ret = mstate->dtms_scratch_ptr;
2834 mstate->dtms_scratch_ptr += strsz;
2835 return (ret);
2836 }
2837
2838 /*
2839 * This function implements the DIF emulator's variable lookups. The emulator
2840 * passes a reserved variable identifier and optional built-in array index.
2841 */
2842 static uint64_t
2843 dtrace_dif_variable(dtrace_mstate_t *mstate, dtrace_state_t *state, uint64_t v,
2844 uint64_t ndx)
2845 {
2846 /*
2847 * If we're accessing one of the uncached arguments, we'll turn this
2848 * into a reference in the args array.
2849 */
2850 if (v >= DIF_VAR_ARG0 && v <= DIF_VAR_ARG9) {
2851 ndx = v - DIF_VAR_ARG0;
2852 v = DIF_VAR_ARGS;
2853 }
2854
2855 switch (v) {
2856 case DIF_VAR_ARGS:
2857 if (!(mstate->dtms_access & DTRACE_ACCESS_ARGS)) {
2858 cpu_core[CPU->cpu_id].cpuc_dtrace_flags |=
2859 CPU_DTRACE_KPRIV;
2860 return (0);
2861 }
2862
2863 ASSERT(mstate->dtms_present & DTRACE_MSTATE_ARGS);
2864 if (ndx >= sizeof (mstate->dtms_arg) /
2865 sizeof (mstate->dtms_arg[0])) {
2866 int aframes = mstate->dtms_probe->dtpr_aframes + 2;
2867 dtrace_provider_t *pv;
2868 uint64_t val;
2869
2870 pv = mstate->dtms_probe->dtpr_provider;
2871 if (pv->dtpv_pops.dtps_getargval != NULL)
2872 val = pv->dtpv_pops.dtps_getargval(pv->dtpv_arg,
2873 mstate->dtms_probe->dtpr_id,
2874 mstate->dtms_probe->dtpr_arg, ndx, aframes);
2875 else
2876 val = dtrace_getarg(ndx, aframes);
2877
2878 /*
2879 * This is regrettably required to keep the compiler
2880 * from tail-optimizing the call to dtrace_getarg().
2881 * The condition always evaluates to true, but the
2882 * compiler has no way of figuring that out a priori.
2883 * (None of this would be necessary if the compiler
2884 * could be relied upon to _always_ tail-optimize
2885 * the call to dtrace_getarg() -- but it can't.)
2886 */
2887 if (mstate->dtms_probe != NULL)
2888 return (val);
2889
2890 ASSERT(0);
2891 }
2892
2893 return (mstate->dtms_arg[ndx]);
2894
2895 case DIF_VAR_UREGS: {
2896 klwp_t *lwp;
2897
2898 if (!dtrace_priv_proc(state, mstate))
2899 return (0);
2900
2901 if ((lwp = curthread->t_lwp) == NULL) {
2902 DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR);
2903 cpu_core[CPU->cpu_id].cpuc_dtrace_illval = NULL;
2904 return (0);
2905 }
2906
2907 return (dtrace_getreg(lwp->lwp_regs, ndx));
2908 }
2909
2910 case DIF_VAR_VMREGS: {
2911 uint64_t rval;
2912
2913 if (!dtrace_priv_kernel(state))
2914 return (0);
2915
2916 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
2917
2918 rval = dtrace_getvmreg(ndx,
2919 &cpu_core[CPU->cpu_id].cpuc_dtrace_flags);
2920
2921 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
2922
2923 return (rval);
2924 }
2925
2926 case DIF_VAR_CURTHREAD:
2927 if (!dtrace_priv_kernel(state))
2928 return (0);
2929 return ((uint64_t)(uintptr_t)curthread);
2930
2931 case DIF_VAR_TIMESTAMP:
2932 if (!(mstate->dtms_present & DTRACE_MSTATE_TIMESTAMP)) {
2933 mstate->dtms_timestamp = dtrace_gethrtime();
2934 mstate->dtms_present |= DTRACE_MSTATE_TIMESTAMP;
2935 }
2936 return (mstate->dtms_timestamp);
2937
2938 case DIF_VAR_VTIMESTAMP:
2939 ASSERT(dtrace_vtime_references != 0);
2940 return (curthread->t_dtrace_vtime);
2941
2942 case DIF_VAR_WALLTIMESTAMP:
2943 if (!(mstate->dtms_present & DTRACE_MSTATE_WALLTIMESTAMP)) {
2944 mstate->dtms_walltimestamp = dtrace_gethrestime();
2945 mstate->dtms_present |= DTRACE_MSTATE_WALLTIMESTAMP;
2946 }
2947 return (mstate->dtms_walltimestamp);
2948
2949 case DIF_VAR_IPL:
2950 if (!dtrace_priv_kernel(state))
2951 return (0);
2952 if (!(mstate->dtms_present & DTRACE_MSTATE_IPL)) {
2953 mstate->dtms_ipl = dtrace_getipl();
2954 mstate->dtms_present |= DTRACE_MSTATE_IPL;
2955 }
2956 return (mstate->dtms_ipl);
2957
2958 case DIF_VAR_EPID:
2959 ASSERT(mstate->dtms_present & DTRACE_MSTATE_EPID);
2960 return (mstate->dtms_epid);
2961
2962 case DIF_VAR_ID:
2963 ASSERT(mstate->dtms_present & DTRACE_MSTATE_PROBE);
2964 return (mstate->dtms_probe->dtpr_id);
2965
2966 case DIF_VAR_STACKDEPTH:
2967 if (!dtrace_priv_kernel(state))
2968 return (0);
2969 if (!(mstate->dtms_present & DTRACE_MSTATE_STACKDEPTH)) {
2970 int aframes = mstate->dtms_probe->dtpr_aframes + 2;
2971
2972 mstate->dtms_stackdepth = dtrace_getstackdepth(aframes);
2973 mstate->dtms_present |= DTRACE_MSTATE_STACKDEPTH;
2974 }
2975 return (mstate->dtms_stackdepth);
2976
2977 case DIF_VAR_USTACKDEPTH:
2978 if (!dtrace_priv_proc(state, mstate))
2979 return (0);
2980 if (!(mstate->dtms_present & DTRACE_MSTATE_USTACKDEPTH)) {
2981 /*
2982 * See comment in DIF_VAR_PID.
2983 */
2984 if (DTRACE_ANCHORED(mstate->dtms_probe) &&
2985 CPU_ON_INTR(CPU)) {
2986 mstate->dtms_ustackdepth = 0;
2987 } else {
2988 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
2989 mstate->dtms_ustackdepth =
2990 dtrace_getustackdepth();
2991 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
2992 }
2993 mstate->dtms_present |= DTRACE_MSTATE_USTACKDEPTH;
2994 }
2995 return (mstate->dtms_ustackdepth);
2996
2997 case DIF_VAR_CALLER:
2998 if (!dtrace_priv_kernel(state))
2999 return (0);
3000 if (!(mstate->dtms_present & DTRACE_MSTATE_CALLER)) {
3001 int aframes = mstate->dtms_probe->dtpr_aframes + 2;
3002
3003 if (!DTRACE_ANCHORED(mstate->dtms_probe)) {
3004 /*
3005 * If this is an unanchored probe, we are
3006 * required to go through the slow path:
3007 * dtrace_caller() only guarantees correct
3008 * results for anchored probes.
3009 */
3010 pc_t caller[2];
3011
3012 dtrace_getpcstack(caller, 2, aframes,
3013 (uint32_t *)(uintptr_t)mstate->dtms_arg[0]);
3014 mstate->dtms_caller = caller[1];
3015 } else if ((mstate->dtms_caller =
3016 dtrace_caller(aframes)) == -1) {
3017 /*
3018 * We have failed to do this the quick way;
3019 * we must resort to the slower approach of
3020 * calling dtrace_getpcstack().
3021 */
3022 pc_t caller;
3023
3024 dtrace_getpcstack(&caller, 1, aframes, NULL);
3025 mstate->dtms_caller = caller;
3026 }
3027
3028 mstate->dtms_present |= DTRACE_MSTATE_CALLER;
3029 }
3030 return (mstate->dtms_caller);
3031
3032 case DIF_VAR_UCALLER:
3033 if (!dtrace_priv_proc(state, mstate))
3034 return (0);
3035
3036 if (!(mstate->dtms_present & DTRACE_MSTATE_UCALLER)) {
3037 uint64_t ustack[3];
3038
3039 /*
3040 * dtrace_getupcstack() fills in the first uint64_t
3041 * with the current PID. The second uint64_t will
3042 * be the program counter at user-level. The third
3043 * uint64_t will contain the caller, which is what
3044 * we're after.
3045 */
3046 ustack[2] = NULL;
3047 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
3048 dtrace_getupcstack(ustack, 3);
3049 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
3050 mstate->dtms_ucaller = ustack[2];
3051 mstate->dtms_present |= DTRACE_MSTATE_UCALLER;
3052 }
3053
3054 return (mstate->dtms_ucaller);
3055
3056 case DIF_VAR_PROBEPROV:
3057 ASSERT(mstate->dtms_present & DTRACE_MSTATE_PROBE);
3058 return (dtrace_dif_varstr(
3059 (uintptr_t)mstate->dtms_probe->dtpr_provider->dtpv_name,
3060 state, mstate));
3061
3062 case DIF_VAR_PROBEMOD:
3063 ASSERT(mstate->dtms_present & DTRACE_MSTATE_PROBE);
3064 return (dtrace_dif_varstr(
3065 (uintptr_t)mstate->dtms_probe->dtpr_mod,
3066 state, mstate));
3067
3068 case DIF_VAR_PROBEFUNC:
3069 ASSERT(mstate->dtms_present & DTRACE_MSTATE_PROBE);
3070 return (dtrace_dif_varstr(
3071 (uintptr_t)mstate->dtms_probe->dtpr_func,
3072 state, mstate));
3073
3074 case DIF_VAR_PROBENAME:
3075 ASSERT(mstate->dtms_present & DTRACE_MSTATE_PROBE);
3076 return (dtrace_dif_varstr(
3077 (uintptr_t)mstate->dtms_probe->dtpr_name,
3078 state, mstate));
3079
3080 case DIF_VAR_PID:
3081 if (!dtrace_priv_proc(state, mstate))
3082 return (0);
3083
3084 /*
3085 * Note that we are assuming that an unanchored probe is
3086 * always due to a high-level interrupt. (And we're assuming
3087 * that there is only a single high level interrupt.)
3088 */
3089 if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU))
3090 return (pid0.pid_id);
3091
3092 /*
3093 * It is always safe to dereference one's own t_procp pointer:
3094 * it always points to a valid, allocated proc structure.
3095 * Further, it is always safe to dereference the p_pidp member
3096 * of one's own proc structure. (These are truisms becuase
3097 * threads and processes don't clean up their own state --
3098 * they leave that task to whomever reaps them.)
3099 */
3100 return ((uint64_t)curthread->t_procp->p_pidp->pid_id);
3101
3102 case DIF_VAR_PPID:
3103 if (!dtrace_priv_proc(state, mstate))
3104 return (0);
3105
3106 /*
3107 * See comment in DIF_VAR_PID.
3108 */
3109 if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU))
3110 return (pid0.pid_id);
3111
3112 /*
3113 * It is always safe to dereference one's own t_procp pointer:
3114 * it always points to a valid, allocated proc structure.
3115 * (This is true because threads don't clean up their own
3116 * state -- they leave that task to whomever reaps them.)
3117 */
3118 return ((uint64_t)curthread->t_procp->p_ppid);
3119
3120 case DIF_VAR_TID:
3121 /*
3122 * See comment in DIF_VAR_PID.
3123 */
3124 if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU))
3125 return (0);
3126
3127 return ((uint64_t)curthread->t_tid);
3128
3129 case DIF_VAR_EXECNAME:
3130 if (!dtrace_priv_proc(state, mstate))
3131 return (0);
3132
3133 /*
3134 * See comment in DIF_VAR_PID.
3135 */
3136 if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU))
3137 return ((uint64_t)(uintptr_t)p0.p_user.u_comm);
3138
3139 /*
3140 * It is always safe to dereference one's own t_procp pointer:
3141 * it always points to a valid, allocated proc structure.
3142 * (This is true because threads don't clean up their own
3143 * state -- they leave that task to whomever reaps them.)
3144 */
3145 return (dtrace_dif_varstr(
3146 (uintptr_t)curthread->t_procp->p_user.u_comm,
3147 state, mstate));
3148
3149 case DIF_VAR_ZONENAME:
3150 if (!dtrace_priv_proc(state, mstate))
3151 return (0);
3152
3153 /*
3154 * See comment in DIF_VAR_PID.
3155 */
3156 if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU))
3157 return ((uint64_t)(uintptr_t)p0.p_zone->zone_name);
3158
3159 /*
3160 * It is always safe to dereference one's own t_procp pointer:
3161 * it always points to a valid, allocated proc structure.
3162 * (This is true because threads don't clean up their own
3163 * state -- they leave that task to whomever reaps them.)
3164 */
3165 return (dtrace_dif_varstr(
3166 (uintptr_t)curthread->t_procp->p_zone->zone_name,
3167 state, mstate));
3168
3169 case DIF_VAR_UID:
3170 if (!dtrace_priv_proc(state, mstate))
3171 return (0);
3172
3173 /*
3174 * See comment in DIF_VAR_PID.
3175 */
3176 if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU))
3177 return ((uint64_t)p0.p_cred->cr_uid);
3178
3179 /*
3180 * It is always safe to dereference one's own t_procp pointer:
3181 * it always points to a valid, allocated proc structure.
3182 * (This is true because threads don't clean up their own
3183 * state -- they leave that task to whomever reaps them.)
3184 *
3185 * Additionally, it is safe to dereference one's own process
3186 * credential, since this is never NULL after process birth.
3187 */
3188 return ((uint64_t)curthread->t_procp->p_cred->cr_uid);
3189
3190 case DIF_VAR_GID:
3191 if (!dtrace_priv_proc(state, mstate))
3192 return (0);
3193
3194 /*
3195 * See comment in DIF_VAR_PID.
3196 */
3197 if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU))
3198 return ((uint64_t)p0.p_cred->cr_gid);
3199
3200 /*
3201 * It is always safe to dereference one's own t_procp pointer:
3202 * it always points to a valid, allocated proc structure.
3203 * (This is true because threads don't clean up their own
3204 * state -- they leave that task to whomever reaps them.)
3205 *
3206 * Additionally, it is safe to dereference one's own process
3207 * credential, since this is never NULL after process birth.
3208 */
3209 return ((uint64_t)curthread->t_procp->p_cred->cr_gid);
3210
3211 case DIF_VAR_ERRNO: {
3212 klwp_t *lwp;
3213 if (!dtrace_priv_proc(state, mstate))
3214 return (0);
3215
3216 /*
3217 * See comment in DIF_VAR_PID.
3218 */
3219 if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU))
3220 return (0);
3221
3222 /*
3223 * It is always safe to dereference one's own t_lwp pointer in
3224 * the event that this pointer is non-NULL. (This is true
3225 * because threads and lwps don't clean up their own state --
3226 * they leave that task to whomever reaps them.)
3227 */
3228 if ((lwp = curthread->t_lwp) == NULL)
3229 return (0);
3230
3231 return ((uint64_t)lwp->lwp_errno);
3232 }
3233 default:
3234 DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP);
3235 return (0);
3236 }
3237 }
3238
3239 /*
3240 * Emulate the execution of DTrace ID subroutines invoked by the call opcode.
3241 * Notice that we don't bother validating the proper number of arguments or
3242 * their types in the tuple stack. This isn't needed because all argument
3243 * interpretation is safe because of our load safety -- the worst that can
3244 * happen is that a bogus program can obtain bogus results.
3245 */
3246 static void
3247 dtrace_dif_subr(uint_t subr, uint_t rd, uint64_t *regs,
3248 dtrace_key_t *tupregs, int nargs,
3249 dtrace_mstate_t *mstate, dtrace_state_t *state)
3250 {
3251 volatile uint16_t *flags = &cpu_core[CPU->cpu_id].cpuc_dtrace_flags;
3252 volatile uintptr_t *illval = &cpu_core[CPU->cpu_id].cpuc_dtrace_illval;
3253 dtrace_vstate_t *vstate = &state->dts_vstate;
3254
3255 union {
3256 mutex_impl_t mi;
3257 uint64_t mx;
3258 } m;
3259
3260 union {
3261 krwlock_t ri;
3262 uintptr_t rw;
3263 } r;
3264
3265 switch (subr) {
3266 case DIF_SUBR_RAND:
3267 regs[rd] = (dtrace_gethrtime() * 2416 + 374441) % 1771875;
3268 break;
3269
3270 case DIF_SUBR_MUTEX_OWNED:
3271 if (!dtrace_canload(tupregs[0].dttk_value, sizeof (kmutex_t),
3272 mstate, vstate)) {
3273 regs[rd] = NULL;
3274 break;
3275 }
3276
3277 m.mx = dtrace_load64(tupregs[0].dttk_value);
3278 if (MUTEX_TYPE_ADAPTIVE(&m.mi))
3279 regs[rd] = MUTEX_OWNER(&m.mi) != MUTEX_NO_OWNER;
3280 else
3281 regs[rd] = LOCK_HELD(&m.mi.m_spin.m_spinlock);
3282 break;
3283
3284 case DIF_SUBR_MUTEX_OWNER:
3285 if (!dtrace_canload(tupregs[0].dttk_value, sizeof (kmutex_t),
3286 mstate, vstate)) {
3287 regs[rd] = NULL;
3288 break;
3289 }
3290
3291 m.mx = dtrace_load64(tupregs[0].dttk_value);
3292 if (MUTEX_TYPE_ADAPTIVE(&m.mi) &&
3293 MUTEX_OWNER(&m.mi) != MUTEX_NO_OWNER)
3294 regs[rd] = (uintptr_t)MUTEX_OWNER(&m.mi);
3295 else
3296 regs[rd] = 0;
3297 break;
3298
3299 case DIF_SUBR_MUTEX_TYPE_ADAPTIVE:
3300 if (!dtrace_canload(tupregs[0].dttk_value, sizeof (kmutex_t),
3301 mstate, vstate)) {
3302 regs[rd] = NULL;
3303 break;
3304 }
3305
3306 m.mx = dtrace_load64(tupregs[0].dttk_value);
3307 regs[rd] = MUTEX_TYPE_ADAPTIVE(&m.mi);
3308 break;
3309
3310 case DIF_SUBR_MUTEX_TYPE_SPIN:
3311 if (!dtrace_canload(tupregs[0].dttk_value, sizeof (kmutex_t),
3312 mstate, vstate)) {
3313 regs[rd] = NULL;
3314 break;
3315 }
3316
3317 m.mx = dtrace_load64(tupregs[0].dttk_value);
3318 regs[rd] = MUTEX_TYPE_SPIN(&m.mi);
3319 break;
3320
3321 case DIF_SUBR_RW_READ_HELD: {
3322 uintptr_t tmp;
3323
3324 if (!dtrace_canload(tupregs[0].dttk_value, sizeof (uintptr_t),
3325 mstate, vstate)) {
3326 regs[rd] = NULL;
3327 break;
3328 }
3329
3330 r.rw = dtrace_loadptr(tupregs[0].dttk_value);
3331 regs[rd] = _RW_READ_HELD(&r.ri, tmp);
3332 break;
3333 }
3334
3335 case DIF_SUBR_RW_WRITE_HELD:
3336 if (!dtrace_canload(tupregs[0].dttk_value, sizeof (krwlock_t),
3337 mstate, vstate)) {
3338 regs[rd] = NULL;
3339 break;
3340 }
3341
3342 r.rw = dtrace_loadptr(tupregs[0].dttk_value);
3343 regs[rd] = _RW_WRITE_HELD(&r.ri);
3344 break;
3345
3346 case DIF_SUBR_RW_ISWRITER:
3347 if (!dtrace_canload(tupregs[0].dttk_value, sizeof (krwlock_t),
3348 mstate, vstate)) {
3349 regs[rd] = NULL;
3350 break;
3351 }
3352
3353 r.rw = dtrace_loadptr(tupregs[0].dttk_value);
3354 regs[rd] = _RW_ISWRITER(&r.ri);
3355 break;
3356
3357 case DIF_SUBR_BCOPY: {
3358 /*
3359 * We need to be sure that the destination is in the scratch
3360 * region -- no other region is allowed.
3361 */
3362 uintptr_t src = tupregs[0].dttk_value;
3363 uintptr_t dest = tupregs[1].dttk_value;
3364 size_t size = tupregs[2].dttk_value;
3365
3366 if (!dtrace_inscratch(dest, size, mstate)) {
3367 *flags |= CPU_DTRACE_BADADDR;
3368 *illval = regs[rd];
3369 break;
3370 }
3371
3372 if (!dtrace_canload(src, size, mstate, vstate)) {
3373 regs[rd] = NULL;
3374 break;
3375 }
3376
3377 dtrace_bcopy((void *)src, (void *)dest, size);
3378 break;
3379 }
3380
3381 case DIF_SUBR_ALLOCA:
3382 case DIF_SUBR_COPYIN: {
3383 uintptr_t dest = P2ROUNDUP(mstate->dtms_scratch_ptr, 8);
3384 uint64_t size =
3385 tupregs[subr == DIF_SUBR_ALLOCA ? 0 : 1].dttk_value;
3386 size_t scratch_size = (dest - mstate->dtms_scratch_ptr) + size;
3387
3388 /*
3389 * This action doesn't require any credential checks since
3390 * probes will not activate in user contexts to which the
3391 * enabling user does not have permissions.
3392 */
3393
3394 /*
3395 * Rounding up the user allocation size could have overflowed
3396 * a large, bogus allocation (like -1ULL) to 0.
3397 */
3398 if (scratch_size < size ||
3399 !DTRACE_INSCRATCH(mstate, scratch_size)) {
3400 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
3401 regs[rd] = NULL;
3402 break;
3403 }
3404
3405 if (subr == DIF_SUBR_COPYIN) {
3406 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
3407 dtrace_copyin(tupregs[0].dttk_value, dest, size, flags);
3408 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
3409 }
3410
3411 mstate->dtms_scratch_ptr += scratch_size;
3412 regs[rd] = dest;
3413 break;
3414 }
3415
3416 case DIF_SUBR_COPYINTO: {
3417 uint64_t size = tupregs[1].dttk_value;
3418 uintptr_t dest = tupregs[2].dttk_value;
3419
3420 /*
3421 * This action doesn't require any credential checks since
3422 * probes will not activate in user contexts to which the
3423 * enabling user does not have permissions.
3424 */
3425 if (!dtrace_inscratch(dest, size, mstate)) {
3426 *flags |= CPU_DTRACE_BADADDR;
3427 *illval = regs[rd];
3428 break;
3429 }
3430
3431 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
3432 dtrace_copyin(tupregs[0].dttk_value, dest, size, flags);
3433 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
3434 break;
3435 }
3436
3437 case DIF_SUBR_COPYINSTR: {
3438 uintptr_t dest = mstate->dtms_scratch_ptr;
3439 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
3440
3441 if (nargs > 1 && tupregs[1].dttk_value < size)
3442 size = tupregs[1].dttk_value + 1;
3443
3444 /*
3445 * This action doesn't require any credential checks since
3446 * probes will not activate in user contexts to which the
3447 * enabling user does not have permissions.
3448 */
3449 if (!DTRACE_INSCRATCH(mstate, size)) {
3450 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
3451 regs[rd] = NULL;
3452 break;
3453 }
3454
3455 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
3456 dtrace_copyinstr(tupregs[0].dttk_value, dest, size, flags);
3457 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
3458
3459 ((char *)dest)[size - 1] = '\0';
3460 mstate->dtms_scratch_ptr += size;
3461 regs[rd] = dest;
3462 break;
3463 }
3464
3465 case DIF_SUBR_MSGSIZE:
3466 case DIF_SUBR_MSGDSIZE: {
3467 uintptr_t baddr = tupregs[0].dttk_value, daddr;
3468 uintptr_t wptr, rptr;
3469 size_t count = 0;
3470 int cont = 0;
3471
3472 while (baddr != NULL && !(*flags & CPU_DTRACE_FAULT)) {
3473
3474 if (!dtrace_canload(baddr, sizeof (mblk_t), mstate,
3475 vstate)) {
3476 regs[rd] = NULL;
3477 break;
3478 }
3479
3480 wptr = dtrace_loadptr(baddr +
3481 offsetof(mblk_t, b_wptr));
3482
3483 rptr = dtrace_loadptr(baddr +
3484 offsetof(mblk_t, b_rptr));
3485
3486 if (wptr < rptr) {
3487 *flags |= CPU_DTRACE_BADADDR;
3488 *illval = tupregs[0].dttk_value;
3489 break;
3490 }
3491
3492 daddr = dtrace_loadptr(baddr +
3493 offsetof(mblk_t, b_datap));
3494
3495 baddr = dtrace_loadptr(baddr +
3496 offsetof(mblk_t, b_cont));
3497
3498 /*
3499 * We want to prevent against denial-of-service here,
3500 * so we're only going to search the list for
3501 * dtrace_msgdsize_max mblks.
3502 */
3503 if (cont++ > dtrace_msgdsize_max) {
3504 *flags |= CPU_DTRACE_ILLOP;
3505 break;
3506 }
3507
3508 if (subr == DIF_SUBR_MSGDSIZE) {
3509 if (dtrace_load8(daddr +
3510 offsetof(dblk_t, db_type)) != M_DATA)
3511 continue;
3512 }
3513
3514 count += wptr - rptr;
3515 }
3516
3517 if (!(*flags & CPU_DTRACE_FAULT))
3518 regs[rd] = count;
3519
3520 break;
3521 }
3522
3523 case DIF_SUBR_PROGENYOF: {
3524 pid_t pid = tupregs[0].dttk_value;
3525 proc_t *p;
3526 int rval = 0;
3527
3528 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
3529
3530 for (p = curthread->t_procp; p != NULL; p = p->p_parent) {
3531 if (p->p_pidp->pid_id == pid) {
3532 rval = 1;
3533 break;
3534 }
3535 }
3536
3537 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
3538
3539 regs[rd] = rval;
3540 break;
3541 }
3542
3543 case DIF_SUBR_SPECULATION:
3544 regs[rd] = dtrace_speculation(state);
3545 break;
3546
3547 case DIF_SUBR_COPYOUT: {
3548 uintptr_t kaddr = tupregs[0].dttk_value;
3549 uintptr_t uaddr = tupregs[1].dttk_value;
3550 uint64_t size = tupregs[2].dttk_value;
3551
3552 if (!dtrace_destructive_disallow &&
3553 dtrace_priv_proc_control(state, mstate) &&
3554 !dtrace_istoxic(kaddr, size)) {
3555 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
3556 dtrace_copyout(kaddr, uaddr, size, flags);
3557 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
3558 }
3559 break;
3560 }
3561
3562 case DIF_SUBR_COPYOUTSTR: {
3563 uintptr_t kaddr = tupregs[0].dttk_value;
3564 uintptr_t uaddr = tupregs[1].dttk_value;
3565 uint64_t size = tupregs[2].dttk_value;
3566
3567 if (!dtrace_destructive_disallow &&
3568 dtrace_priv_proc_control(state, mstate) &&
3569 !dtrace_istoxic(kaddr, size)) {
3570 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
3571 dtrace_copyoutstr(kaddr, uaddr, size, flags);
3572 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
3573 }
3574 break;
3575 }
3576
3577 case DIF_SUBR_STRLEN: {
3578 size_t sz;
3579 uintptr_t addr = (uintptr_t)tupregs[0].dttk_value;
3580 sz = dtrace_strlen((char *)addr,
3581 state->dts_options[DTRACEOPT_STRSIZE]);
3582
3583 if (!dtrace_canload(addr, sz + 1, mstate, vstate)) {
3584 regs[rd] = NULL;
3585 break;
3586 }
3587
3588 regs[rd] = sz;
3589
3590 break;
3591 }
3592
3593 case DIF_SUBR_STRCHR:
3594 case DIF_SUBR_STRRCHR: {
3595 /*
3596 * We're going to iterate over the string looking for the
3597 * specified character. We will iterate until we have reached
3598 * the string length or we have found the character. If this
3599 * is DIF_SUBR_STRRCHR, we will look for the last occurrence
3600 * of the specified character instead of the first.
3601 */
3602 uintptr_t saddr = tupregs[0].dttk_value;
3603 uintptr_t addr = tupregs[0].dttk_value;
3604 uintptr_t limit = addr + state->dts_options[DTRACEOPT_STRSIZE];
3605 char c, target = (char)tupregs[1].dttk_value;
3606
3607 for (regs[rd] = NULL; addr < limit; addr++) {
3608 if ((c = dtrace_load8(addr)) == target) {
3609 regs[rd] = addr;
3610
3611 if (subr == DIF_SUBR_STRCHR)
3612 break;
3613 }
3614
3615 if (c == '\0')
3616 break;
3617 }
3618
3619 if (!dtrace_canload(saddr, addr - saddr, mstate, vstate)) {
3620 regs[rd] = NULL;
3621 break;
3622 }
3623
3624 break;
3625 }
3626
3627 case DIF_SUBR_STRSTR:
3628 case DIF_SUBR_INDEX:
3629 case DIF_SUBR_RINDEX: {
3630 /*
3631 * We're going to iterate over the string looking for the
3632 * specified string. We will iterate until we have reached
3633 * the string length or we have found the string. (Yes, this
3634 * is done in the most naive way possible -- but considering
3635 * that the string we're searching for is likely to be
3636 * relatively short, the complexity of Rabin-Karp or similar
3637 * hardly seems merited.)
3638 */
3639 char *addr = (char *)(uintptr_t)tupregs[0].dttk_value;
3640 char *substr = (char *)(uintptr_t)tupregs[1].dttk_value;
3641 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
3642 size_t len = dtrace_strlen(addr, size);
3643 size_t sublen = dtrace_strlen(substr, size);
3644 char *limit = addr + len, *orig = addr;
3645 int notfound = subr == DIF_SUBR_STRSTR ? 0 : -1;
3646 int inc = 1;
3647
3648 regs[rd] = notfound;
3649
3650 if (!dtrace_canload((uintptr_t)addr, len + 1, mstate, vstate)) {
3651 regs[rd] = NULL;
3652 break;
3653 }
3654
3655 if (!dtrace_canload((uintptr_t)substr, sublen + 1, mstate,
3656 vstate)) {
3657 regs[rd] = NULL;
3658 break;
3659 }
3660
3661 /*
3662 * strstr() and index()/rindex() have similar semantics if
3663 * both strings are the empty string: strstr() returns a
3664 * pointer to the (empty) string, and index() and rindex()
3665 * both return index 0 (regardless of any position argument).
3666 */
3667 if (sublen == 0 && len == 0) {
3668 if (subr == DIF_SUBR_STRSTR)
3669 regs[rd] = (uintptr_t)addr;
3670 else
3671 regs[rd] = 0;
3672 break;
3673 }
3674
3675 if (subr != DIF_SUBR_STRSTR) {
3676 if (subr == DIF_SUBR_RINDEX) {
3677 limit = orig - 1;
3678 addr += len;
3679 inc = -1;
3680 }
3681
3682 /*
3683 * Both index() and rindex() take an optional position
3684 * argument that denotes the starting position.
3685 */
3686 if (nargs == 3) {
3687 int64_t pos = (int64_t)tupregs[2].dttk_value;
3688
3689 /*
3690 * If the position argument to index() is
3691 * negative, Perl implicitly clamps it at
3692 * zero. This semantic is a little surprising
3693 * given the special meaning of negative
3694 * positions to similar Perl functions like
3695 * substr(), but it appears to reflect a
3696 * notion that index() can start from a
3697 * negative index and increment its way up to
3698 * the string. Given this notion, Perl's
3699 * rindex() is at least self-consistent in
3700 * that it implicitly clamps positions greater
3701 * than the string length to be the string
3702 * length. Where Perl completely loses
3703 * coherence, however, is when the specified
3704 * substring is the empty string (""). In
3705 * this case, even if the position is
3706 * negative, rindex() returns 0 -- and even if
3707 * the position is greater than the length,
3708 * index() returns the string length. These
3709 * semantics violate the notion that index()
3710 * should never return a value less than the
3711 * specified position and that rindex() should
3712 * never return a value greater than the
3713 * specified position. (One assumes that
3714 * these semantics are artifacts of Perl's
3715 * implementation and not the results of
3716 * deliberate design -- it beggars belief that
3717 * even Larry Wall could desire such oddness.)
3718 * While in the abstract one would wish for
3719 * consistent position semantics across
3720 * substr(), index() and rindex() -- or at the
3721 * very least self-consistent position
3722 * semantics for index() and rindex() -- we
3723 * instead opt to keep with the extant Perl
3724 * semantics, in all their broken glory. (Do
3725 * we have more desire to maintain Perl's
3726 * semantics than Perl does? Probably.)
3727 */
3728 if (subr == DIF_SUBR_RINDEX) {
3729 if (pos < 0) {
3730 if (sublen == 0)
3731 regs[rd] = 0;
3732 break;
3733 }
3734
3735 if (pos > len)
3736 pos = len;
3737 } else {
3738 if (pos < 0)
3739 pos = 0;
3740
3741 if (pos >= len) {
3742 if (sublen == 0)
3743 regs[rd] = len;
3744 break;
3745 }
3746 }
3747
3748 addr = orig + pos;
3749 }
3750 }
3751
3752 for (regs[rd] = notfound; addr != limit; addr += inc) {
3753 if (dtrace_strncmp(addr, substr, sublen) == 0) {
3754 if (subr != DIF_SUBR_STRSTR) {
3755 /*
3756 * As D index() and rindex() are
3757 * modeled on Perl (and not on awk),
3758 * we return a zero-based (and not a
3759 * one-based) index. (For you Perl
3760 * weenies: no, we're not going to add
3761 * $[ -- and shouldn't you be at a con
3762 * or something?)
3763 */
3764 regs[rd] = (uintptr_t)(addr - orig);
3765 break;
3766 }
3767
3768 ASSERT(subr == DIF_SUBR_STRSTR);
3769 regs[rd] = (uintptr_t)addr;
3770 break;
3771 }
3772 }
3773
3774 break;
3775 }
3776
3777 case DIF_SUBR_STRTOK: {
3778 uintptr_t addr = tupregs[0].dttk_value;
3779 uintptr_t tokaddr = tupregs[1].dttk_value;
3780 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
3781 uintptr_t limit, toklimit = tokaddr + size;
3782 uint8_t c, tokmap[32]; /* 256 / 8 */
3783 char *dest = (char *)mstate->dtms_scratch_ptr;
3784 int i;
3785
3786 /*
3787 * Check both the token buffer and (later) the input buffer,
3788 * since both could be non-scratch addresses.
3789 */
3790 if (!dtrace_strcanload(tokaddr, size, mstate, vstate)) {
3791 regs[rd] = NULL;
3792 break;
3793 }
3794
3795 if (!DTRACE_INSCRATCH(mstate, size)) {
3796 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
3797 regs[rd] = NULL;
3798 break;
3799 }
3800
3801 if (addr == NULL) {
3802 /*
3803 * If the address specified is NULL, we use our saved
3804 * strtok pointer from the mstate. Note that this
3805 * means that the saved strtok pointer is _only_
3806 * valid within multiple enablings of the same probe --
3807 * it behaves like an implicit clause-local variable.
3808 */
3809 addr = mstate->dtms_strtok;
3810 } else {
3811 /*
3812 * If the user-specified address is non-NULL we must
3813 * access check it. This is the only time we have
3814 * a chance to do so, since this address may reside
3815 * in the string table of this clause-- future calls
3816 * (when we fetch addr from mstate->dtms_strtok)
3817 * would fail this access check.
3818 */
3819 if (!dtrace_strcanload(addr, size, mstate, vstate)) {
3820 regs[rd] = NULL;
3821 break;
3822 }
3823 }
3824
3825 /*
3826 * First, zero the token map, and then process the token
3827 * string -- setting a bit in the map for every character
3828 * found in the token string.
3829 */
3830 for (i = 0; i < sizeof (tokmap); i++)
3831 tokmap[i] = 0;
3832
3833 for (; tokaddr < toklimit; tokaddr++) {
3834 if ((c = dtrace_load8(tokaddr)) == '\0')
3835 break;
3836
3837 ASSERT((c >> 3) < sizeof (tokmap));
3838 tokmap[c >> 3] |= (1 << (c & 0x7));
3839 }
3840
3841 for (limit = addr + size; addr < limit; addr++) {
3842 /*
3843 * We're looking for a character that is _not_ contained
3844 * in the token string.
3845 */
3846 if ((c = dtrace_load8(addr)) == '\0')
3847 break;
3848
3849 if (!(tokmap[c >> 3] & (1 << (c & 0x7))))
3850 break;
3851 }
3852
3853 if (c == '\0') {
3854 /*
3855 * We reached the end of the string without finding
3856 * any character that was not in the token string.
3857 * We return NULL in this case, and we set the saved
3858 * address to NULL as well.
3859 */
3860 regs[rd] = NULL;
3861 mstate->dtms_strtok = NULL;
3862 break;
3863 }
3864
3865 /*
3866 * From here on, we're copying into the destination string.
3867 */
3868 for (i = 0; addr < limit && i < size - 1; addr++) {
3869 if ((c = dtrace_load8(addr)) == '\0')
3870 break;
3871
3872 if (tokmap[c >> 3] & (1 << (c & 0x7)))
3873 break;
3874
3875 ASSERT(i < size);
3876 dest[i++] = c;
3877 }
3878
3879 ASSERT(i < size);
3880 dest[i] = '\0';
3881 regs[rd] = (uintptr_t)dest;
3882 mstate->dtms_scratch_ptr += size;
3883 mstate->dtms_strtok = addr;
3884 break;
3885 }
3886
3887 case DIF_SUBR_SUBSTR: {
3888 uintptr_t s = tupregs[0].dttk_value;
3889 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
3890 char *d = (char *)mstate->dtms_scratch_ptr;
3891 int64_t index = (int64_t)tupregs[1].dttk_value;
3892 int64_t remaining = (int64_t)tupregs[2].dttk_value;
3893 size_t len = dtrace_strlen((char *)s, size);
3894 int64_t i;
3895
3896 if (!dtrace_canload(s, len + 1, mstate, vstate)) {
3897 regs[rd] = NULL;
3898 break;
3899 }
3900
3901 if (!DTRACE_INSCRATCH(mstate, size)) {
3902 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
3903 regs[rd] = NULL;
3904 break;
3905 }
3906
3907 if (nargs <= 2)
3908 remaining = (int64_t)size;
3909
3910 if (index < 0) {
3911 index += len;
3912
3913 if (index < 0 && index + remaining > 0) {
3914 remaining += index;
3915 index = 0;
3916 }
3917 }
3918
3919 if (index >= len || index < 0) {
3920 remaining = 0;
3921 } else if (remaining < 0) {
3922 remaining += len - index;
3923 } else if (index + remaining > size) {
3924 remaining = size - index;
3925 }
3926
3927 for (i = 0; i < remaining; i++) {
3928 if ((d[i] = dtrace_load8(s + index + i)) == '\0')
3929 break;
3930 }
3931
3932 d[i] = '\0';
3933
3934 mstate->dtms_scratch_ptr += size;
3935 regs[rd] = (uintptr_t)d;
3936 break;
3937 }
3938
3939 case DIF_SUBR_TOUPPER:
3940 case DIF_SUBR_TOLOWER: {
3941 uintptr_t s = tupregs[0].dttk_value;
3942 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
3943 char *dest = (char *)mstate->dtms_scratch_ptr, c;
3944 size_t len = dtrace_strlen((char *)s, size);
3945 char lower, upper, convert;
3946 int64_t i;
3947
3948 if (subr == DIF_SUBR_TOUPPER) {
3949 lower = 'a';
3950 upper = 'z';
3951 convert = 'A';
3952 } else {
3953 lower = 'A';
3954 upper = 'Z';
3955 convert = 'a';
3956 }
3957
3958 if (!dtrace_canload(s, len + 1, mstate, vstate)) {
3959 regs[rd] = NULL;
3960 break;
3961 }
3962
3963 if (!DTRACE_INSCRATCH(mstate, size)) {
3964 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
3965 regs[rd] = NULL;
3966 break;
3967 }
3968
3969 for (i = 0; i < size - 1; i++) {
3970 if ((c = dtrace_load8(s + i)) == '\0')
3971 break;
3972
3973 if (c >= lower && c <= upper)
3974 c = convert + (c - lower);
3975
3976 dest[i] = c;
3977 }
3978
3979 ASSERT(i < size);
3980 dest[i] = '\0';
3981 regs[rd] = (uintptr_t)dest;
3982 mstate->dtms_scratch_ptr += size;
3983 break;
3984 }
3985
3986 case DIF_SUBR_GETMAJOR:
3987 #ifdef _LP64
3988 regs[rd] = (tupregs[0].dttk_value >> NBITSMINOR64) & MAXMAJ64;
3989 #else
3990 regs[rd] = (tupregs[0].dttk_value >> NBITSMINOR) & MAXMAJ;
3991 #endif
3992 break;
3993
3994 case DIF_SUBR_GETMINOR:
3995 #ifdef _LP64
3996 regs[rd] = tupregs[0].dttk_value & MAXMIN64;
3997 #else
3998 regs[rd] = tupregs[0].dttk_value & MAXMIN;
3999 #endif
4000 break;
4001
4002 case DIF_SUBR_DDI_PATHNAME: {
4003 /*
4004 * This one is a galactic mess. We are going to roughly
4005 * emulate ddi_pathname(), but it's made more complicated
4006 * by the fact that we (a) want to include the minor name and
4007 * (b) must proceed iteratively instead of recursively.
4008 */
4009 uintptr_t dest = mstate->dtms_scratch_ptr;
4010 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
4011 char *start = (char *)dest, *end = start + size - 1;
4012 uintptr_t daddr = tupregs[0].dttk_value;
4013 int64_t minor = (int64_t)tupregs[1].dttk_value;
4014 char *s;
4015 int i, len, depth = 0;
4016
4017 /*
4018 * Due to all the pointer jumping we do and context we must
4019 * rely upon, we just mandate that the user must have kernel
4020 * read privileges to use this routine.
4021 */
4022 if ((mstate->dtms_access & DTRACE_ACCESS_KERNEL) == 0) {
4023 *flags |= CPU_DTRACE_KPRIV;
4024 *illval = daddr;
4025 regs[rd] = NULL;
4026 }
4027
4028 if (!DTRACE_INSCRATCH(mstate, size)) {
4029 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
4030 regs[rd] = NULL;
4031 break;
4032 }
4033
4034 *end = '\0';
4035
4036 /*
4037 * We want to have a name for the minor. In order to do this,
4038 * we need to walk the minor list from the devinfo. We want
4039 * to be sure that we don't infinitely walk a circular list,
4040 * so we check for circularity by sending a scout pointer
4041 * ahead two elements for every element that we iterate over;
4042 * if the list is circular, these will ultimately point to the
4043 * same element. You may recognize this little trick as the
4044 * answer to a stupid interview question -- one that always
4045 * seems to be asked by those who had to have it laboriously
4046 * explained to them, and who can't even concisely describe
4047 * the conditions under which one would be forced to resort to
4048 * this technique. Needless to say, those conditions are
4049 * found here -- and probably only here. Is this the only use
4050 * of this infamous trick in shipping, production code? If it
4051 * isn't, it probably should be...
4052 */
4053 if (minor != -1) {
4054 uintptr_t maddr = dtrace_loadptr(daddr +
4055 offsetof(struct dev_info, devi_minor));
4056
4057 uintptr_t next = offsetof(struct ddi_minor_data, next);
4058 uintptr_t name = offsetof(struct ddi_minor_data,
4059 d_minor) + offsetof(struct ddi_minor, name);
4060 uintptr_t dev = offsetof(struct ddi_minor_data,
4061 d_minor) + offsetof(struct ddi_minor, dev);
4062 uintptr_t scout;
4063
4064 if (maddr != NULL)
4065 scout = dtrace_loadptr(maddr + next);
4066
4067 while (maddr != NULL && !(*flags & CPU_DTRACE_FAULT)) {
4068 uint64_t m;
4069 #ifdef _LP64
4070 m = dtrace_load64(maddr + dev) & MAXMIN64;
4071 #else
4072 m = dtrace_load32(maddr + dev) & MAXMIN;
4073 #endif
4074 if (m != minor) {
4075 maddr = dtrace_loadptr(maddr + next);
4076
4077 if (scout == NULL)
4078 continue;
4079
4080 scout = dtrace_loadptr(scout + next);
4081
4082 if (scout == NULL)
4083 continue;
4084
4085 scout = dtrace_loadptr(scout + next);
4086
4087 if (scout == NULL)
4088 continue;
4089
4090 if (scout == maddr) {
4091 *flags |= CPU_DTRACE_ILLOP;
4092 break;
4093 }
4094
4095 continue;
4096 }
4097
4098 /*
4099 * We have the minor data. Now we need to
4100 * copy the minor's name into the end of the
4101 * pathname.
4102 */
4103 s = (char *)dtrace_loadptr(maddr + name);
4104 len = dtrace_strlen(s, size);
4105
4106 if (*flags & CPU_DTRACE_FAULT)
4107 break;
4108
4109 if (len != 0) {
4110 if ((end -= (len + 1)) < start)
4111 break;
4112
4113 *end = ':';
4114 }
4115
4116 for (i = 1; i <= len; i++)
4117 end[i] = dtrace_load8((uintptr_t)s++);
4118 break;
4119 }
4120 }
4121
4122 while (daddr != NULL && !(*flags & CPU_DTRACE_FAULT)) {
4123 ddi_node_state_t devi_state;
4124
4125 devi_state = dtrace_load32(daddr +
4126 offsetof(struct dev_info, devi_node_state));
4127
4128 if (*flags & CPU_DTRACE_FAULT)
4129 break;
4130
4131 if (devi_state >= DS_INITIALIZED) {
4132 s = (char *)dtrace_loadptr(daddr +
4133 offsetof(struct dev_info, devi_addr));
4134 len = dtrace_strlen(s, size);
4135
4136 if (*flags & CPU_DTRACE_FAULT)
4137 break;
4138
4139 if (len != 0) {
4140 if ((end -= (len + 1)) < start)
4141 break;
4142
4143 *end = '@';
4144 }
4145
4146 for (i = 1; i <= len; i++)
4147 end[i] = dtrace_load8((uintptr_t)s++);
4148 }
4149
4150 /*
4151 * Now for the node name...
4152 */
4153 s = (char *)dtrace_loadptr(daddr +
4154 offsetof(struct dev_info, devi_node_name));
4155
4156 daddr = dtrace_loadptr(daddr +
4157 offsetof(struct dev_info, devi_parent));
4158
4159 /*
4160 * If our parent is NULL (that is, if we're the root
4161 * node), we're going to use the special path
4162 * "devices".
4163 */
4164 if (daddr == NULL)
4165 s = "devices";
4166
4167 len = dtrace_strlen(s, size);
4168 if (*flags & CPU_DTRACE_FAULT)
4169 break;
4170
4171 if ((end -= (len + 1)) < start)
4172 break;
4173
4174 for (i = 1; i <= len; i++)
4175 end[i] = dtrace_load8((uintptr_t)s++);
4176 *end = '/';
4177
4178 if (depth++ > dtrace_devdepth_max) {
4179 *flags |= CPU_DTRACE_ILLOP;
4180 break;
4181 }
4182 }
4183
4184 if (end < start)
4185 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
4186
4187 if (daddr == NULL) {
4188 regs[rd] = (uintptr_t)end;
4189 mstate->dtms_scratch_ptr += size;
4190 }
4191
4192 break;
4193 }
4194
4195 case DIF_SUBR_STRJOIN: {
4196 char *d = (char *)mstate->dtms_scratch_ptr;
4197 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
4198 uintptr_t s1 = tupregs[0].dttk_value;
4199 uintptr_t s2 = tupregs[1].dttk_value;
4200 int i = 0;
4201
4202 if (!dtrace_strcanload(s1, size, mstate, vstate) ||
4203 !dtrace_strcanload(s2, size, mstate, vstate)) {
4204 regs[rd] = NULL;
4205 break;
4206 }
4207
4208 if (!DTRACE_INSCRATCH(mstate, size)) {
4209 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
4210 regs[rd] = NULL;
4211 break;
4212 }
4213
4214 for (;;) {
4215 if (i >= size) {
4216 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
4217 regs[rd] = NULL;
4218 break;
4219 }
4220
4221 if ((d[i++] = dtrace_load8(s1++)) == '\0') {
4222 i--;
4223 break;
4224 }
4225 }
4226
4227 for (;;) {
4228 if (i >= size) {
4229 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
4230 regs[rd] = NULL;
4231 break;
4232 }
4233
4234 if ((d[i++] = dtrace_load8(s2++)) == '\0')
4235 break;
4236 }
4237
4238 if (i < size) {
4239 mstate->dtms_scratch_ptr += i;
4240 regs[rd] = (uintptr_t)d;
4241 }
4242
4243 break;
4244 }
4245
4246 case DIF_SUBR_LLTOSTR: {
4247 int64_t i = (int64_t)tupregs[0].dttk_value;
4248 uint64_t val, digit;
4249 uint64_t size = 65; /* enough room for 2^64 in binary */
4250 char *end = (char *)mstate->dtms_scratch_ptr + size - 1;
4251 int base = 10;
4252
4253 if (nargs > 1) {
4254 if ((base = tupregs[1].dttk_value) <= 1 ||
4255 base > ('z' - 'a' + 1) + ('9' - '0' + 1)) {
4256 *flags |= CPU_DTRACE_ILLOP;
4257 break;
4258 }
4259 }
4260
4261 val = (base == 10 && i < 0) ? i * -1 : i;
4262
4263 if (!DTRACE_INSCRATCH(mstate, size)) {
4264 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
4265 regs[rd] = NULL;
4266 break;
4267 }
4268
4269 for (*end-- = '\0'; val; val /= base) {
4270 if ((digit = val % base) <= '9' - '0') {
4271 *end-- = '0' + digit;
4272 } else {
4273 *end-- = 'a' + (digit - ('9' - '0') - 1);
4274 }
4275 }
4276
4277 if (i == 0 && base == 16)
4278 *end-- = '0';
4279
4280 if (base == 16)
4281 *end-- = 'x';
4282
4283 if (i == 0 || base == 8 || base == 16)
4284 *end-- = '0';
4285
4286 if (i < 0 && base == 10)
4287 *end-- = '-';
4288
4289 regs[rd] = (uintptr_t)end + 1;
4290 mstate->dtms_scratch_ptr += size;
4291 break;
4292 }
4293
4294 case DIF_SUBR_HTONS:
4295 case DIF_SUBR_NTOHS:
4296 #ifdef _BIG_ENDIAN
4297 regs[rd] = (uint16_t)tupregs[0].dttk_value;
4298 #else
4299 regs[rd] = DT_BSWAP_16((uint16_t)tupregs[0].dttk_value);
4300 #endif
4301 break;
4302
4303
4304 case DIF_SUBR_HTONL:
4305 case DIF_SUBR_NTOHL:
4306 #ifdef _BIG_ENDIAN
4307 regs[rd] = (uint32_t)tupregs[0].dttk_value;
4308 #else
4309 regs[rd] = DT_BSWAP_32((uint32_t)tupregs[0].dttk_value);
4310 #endif
4311 break;
4312
4313
4314 case DIF_SUBR_HTONLL:
4315 case DIF_SUBR_NTOHLL:
4316 #ifdef _BIG_ENDIAN
4317 regs[rd] = (uint64_t)tupregs[0].dttk_value;
4318 #else
4319 regs[rd] = DT_BSWAP_64((uint64_t)tupregs[0].dttk_value);
4320 #endif
4321 break;
4322
4323
4324 case DIF_SUBR_DIRNAME:
4325 case DIF_SUBR_BASENAME: {
4326 char *dest = (char *)mstate->dtms_scratch_ptr;
4327 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
4328 uintptr_t src = tupregs[0].dttk_value;
4329 int i, j, len = dtrace_strlen((char *)src, size);
4330 int lastbase = -1, firstbase = -1, lastdir = -1;
4331 int start, end;
4332
4333 if (!dtrace_canload(src, len + 1, mstate, vstate)) {
4334 regs[rd] = NULL;
4335 break;
4336 }
4337
4338 if (!DTRACE_INSCRATCH(mstate, size)) {
4339 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
4340 regs[rd] = NULL;
4341 break;
4342 }
4343
4344 /*
4345 * The basename and dirname for a zero-length string is
4346 * defined to be "."
4347 */
4348 if (len == 0) {
4349 len = 1;
4350 src = (uintptr_t)".";
4351 }
4352
4353 /*
4354 * Start from the back of the string, moving back toward the
4355 * front until we see a character that isn't a slash. That
4356 * character is the last character in the basename.
4357 */
4358 for (i = len - 1; i >= 0; i--) {
4359 if (dtrace_load8(src + i) != '/')
4360 break;
4361 }
4362
4363 if (i >= 0)
4364 lastbase = i;
4365
4366 /*
4367 * Starting from the last character in the basename, move
4368 * towards the front until we find a slash. The character
4369 * that we processed immediately before that is the first
4370 * character in the basename.
4371 */
4372 for (; i >= 0; i--) {
4373 if (dtrace_load8(src + i) == '/')
4374 break;
4375 }
4376
4377 if (i >= 0)
4378 firstbase = i + 1;
4379
4380 /*
4381 * Now keep going until we find a non-slash character. That
4382 * character is the last character in the dirname.
4383 */
4384 for (; i >= 0; i--) {
4385 if (dtrace_load8(src + i) != '/')
4386 break;
4387 }
4388
4389 if (i >= 0)
4390 lastdir = i;
4391
4392 ASSERT(!(lastbase == -1 && firstbase != -1));
4393 ASSERT(!(firstbase == -1 && lastdir != -1));
4394
4395 if (lastbase == -1) {
4396 /*
4397 * We didn't find a non-slash character. We know that
4398 * the length is non-zero, so the whole string must be
4399 * slashes. In either the dirname or the basename
4400 * case, we return '/'.
4401 */
4402 ASSERT(firstbase == -1);
4403 firstbase = lastbase = lastdir = 0;
4404 }
4405
4406 if (firstbase == -1) {
4407 /*
4408 * The entire string consists only of a basename
4409 * component. If we're looking for dirname, we need
4410 * to change our string to be just "."; if we're
4411 * looking for a basename, we'll just set the first
4412 * character of the basename to be 0.
4413 */
4414 if (subr == DIF_SUBR_DIRNAME) {
4415 ASSERT(lastdir == -1);
4416 src = (uintptr_t)".";
4417 lastdir = 0;
4418 } else {
4419 firstbase = 0;
4420 }
4421 }
4422
4423 if (subr == DIF_SUBR_DIRNAME) {
4424 if (lastdir == -1) {
4425 /*
4426 * We know that we have a slash in the name --
4427 * or lastdir would be set to 0, above. And
4428 * because lastdir is -1, we know that this
4429 * slash must be the first character. (That
4430 * is, the full string must be of the form
4431 * "/basename".) In this case, the last
4432 * character of the directory name is 0.
4433 */
4434 lastdir = 0;
4435 }
4436
4437 start = 0;
4438 end = lastdir;
4439 } else {
4440 ASSERT(subr == DIF_SUBR_BASENAME);
4441 ASSERT(firstbase != -1 && lastbase != -1);
4442 start = firstbase;
4443 end = lastbase;
4444 }
4445
4446 for (i = start, j = 0; i <= end && j < size - 1; i++, j++)
4447 dest[j] = dtrace_load8(src + i);
4448
4449 dest[j] = '\0';
4450 regs[rd] = (uintptr_t)dest;
4451 mstate->dtms_scratch_ptr += size;
4452 break;
4453 }
4454
4455 case DIF_SUBR_CLEANPATH: {
4456 char *dest = (char *)mstate->dtms_scratch_ptr, c;
4457 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
4458 uintptr_t src = tupregs[0].dttk_value;
4459 int i = 0, j = 0;
4460
4461 if (!dtrace_strcanload(src, size, mstate, vstate)) {
4462 regs[rd] = NULL;
4463 break;
4464 }
4465
4466 if (!DTRACE_INSCRATCH(mstate, size)) {
4467 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
4468 regs[rd] = NULL;
4469 break;
4470 }
4471
4472 /*
4473 * Move forward, loading each character.
4474 */
4475 do {
4476 c = dtrace_load8(src + i++);
4477 next:
4478 if (j + 5 >= size) /* 5 = strlen("/..c\0") */
4479 break;
4480
4481 if (c != '/') {
4482 dest[j++] = c;
4483 continue;
4484 }
4485
4486 c = dtrace_load8(src + i++);
4487
4488 if (c == '/') {
4489 /*
4490 * We have two slashes -- we can just advance
4491 * to the next character.
4492 */
4493 goto next;
4494 }
4495
4496 if (c != '.') {
4497 /*
4498 * This is not "." and it's not ".." -- we can
4499 * just store the "/" and this character and
4500 * drive on.
4501 */
4502 dest[j++] = '/';
4503 dest[j++] = c;
4504 continue;
4505 }
4506
4507 c = dtrace_load8(src + i++);
4508
4509 if (c == '/') {
4510 /*
4511 * This is a "/./" component. We're not going
4512 * to store anything in the destination buffer;
4513 * we're just going to go to the next component.
4514 */
4515 goto next;
4516 }
4517
4518 if (c != '.') {
4519 /*
4520 * This is not ".." -- we can just store the
4521 * "/." and this character and continue
4522 * processing.
4523 */
4524 dest[j++] = '/';
4525 dest[j++] = '.';
4526 dest[j++] = c;
4527 continue;
4528 }
4529
4530 c = dtrace_load8(src + i++);
4531
4532 if (c != '/' && c != '\0') {
4533 /*
4534 * This is not ".." -- it's "..[mumble]".
4535 * We'll store the "/.." and this character
4536 * and continue processing.
4537 */
4538 dest[j++] = '/';
4539 dest[j++] = '.';
4540 dest[j++] = '.';
4541 dest[j++] = c;
4542 continue;
4543 }
4544
4545 /*
4546 * This is "/../" or "/..\0". We need to back up
4547 * our destination pointer until we find a "/".
4548 */
4549 i--;
4550 while (j != 0 && dest[--j] != '/')
4551 continue;
4552
4553 if (c == '\0')
4554 dest[++j] = '/';
4555 } while (c != '\0');
4556
4557 dest[j] = '\0';
4558 regs[rd] = (uintptr_t)dest;
4559 mstate->dtms_scratch_ptr += size;
4560 break;
4561 }
4562
4563 case DIF_SUBR_INET_NTOA:
4564 case DIF_SUBR_INET_NTOA6:
4565 case DIF_SUBR_INET_NTOP: {
4566 size_t size;
4567 int af, argi, i;
4568 char *base, *end;
4569
4570 if (subr == DIF_SUBR_INET_NTOP) {
4571 af = (int)tupregs[0].dttk_value;
4572 argi = 1;
4573 } else {
4574 af = subr == DIF_SUBR_INET_NTOA ? AF_INET: AF_INET6;
4575 argi = 0;
4576 }
4577
4578 if (af == AF_INET) {
4579 ipaddr_t ip4;
4580 uint8_t *ptr8, val;
4581
4582 /*
4583 * Safely load the IPv4 address.
4584 */
4585 ip4 = dtrace_load32(tupregs[argi].dttk_value);
4586
4587 /*
4588 * Check an IPv4 string will fit in scratch.
4589 */
4590 size = INET_ADDRSTRLEN;
4591 if (!DTRACE_INSCRATCH(mstate, size)) {
4592 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
4593 regs[rd] = NULL;
4594 break;
4595 }
4596 base = (char *)mstate->dtms_scratch_ptr;
4597 end = (char *)mstate->dtms_scratch_ptr + size - 1;
4598
4599 /*
4600 * Stringify as a dotted decimal quad.
4601 */
4602 *end-- = '\0';
4603 ptr8 = (uint8_t *)&ip4;
4604 for (i = 3; i >= 0; i--) {
4605 val = ptr8[i];
4606
4607 if (val == 0) {
4608 *end-- = '0';
4609 } else {
4610 for (; val; val /= 10) {
4611 *end-- = '0' + (val % 10);
4612 }
4613 }
4614
4615 if (i > 0)
4616 *end-- = '.';
4617 }
4618 ASSERT(end + 1 >= base);
4619
4620 } else if (af == AF_INET6) {
4621 struct in6_addr ip6;
4622 int firstzero, tryzero, numzero, v6end;
4623 uint16_t val;
4624 const char digits[] = "0123456789abcdef";
4625
4626 /*
4627 * Stringify using RFC 1884 convention 2 - 16 bit
4628 * hexadecimal values with a zero-run compression.
4629 * Lower case hexadecimal digits are used.
4630 * eg, fe80::214:4fff:fe0b:76c8.
4631 * The IPv4 embedded form is returned for inet_ntop,
4632 * just the IPv4 string is returned for inet_ntoa6.
4633 */
4634
4635 /*
4636 * Safely load the IPv6 address.
4637 */
4638 dtrace_bcopy(
4639 (void *)(uintptr_t)tupregs[argi].dttk_value,
4640 (void *)(uintptr_t)&ip6, sizeof (struct in6_addr));
4641
4642 /*
4643 * Check an IPv6 string will fit in scratch.
4644 */
4645 size = INET6_ADDRSTRLEN;
4646 if (!DTRACE_INSCRATCH(mstate, size)) {
4647 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
4648 regs[rd] = NULL;
4649 break;
4650 }
4651 base = (char *)mstate->dtms_scratch_ptr;
4652 end = (char *)mstate->dtms_scratch_ptr + size - 1;
4653 *end-- = '\0';
4654
4655 /*
4656 * Find the longest run of 16 bit zero values
4657 * for the single allowed zero compression - "::".
4658 */
4659 firstzero = -1;
4660 tryzero = -1;
4661 numzero = 1;
4662 for (i = 0; i < sizeof (struct in6_addr); i++) {
4663 if (ip6._S6_un._S6_u8[i] == 0 &&
4664 tryzero == -1 && i % 2 == 0) {
4665 tryzero = i;
4666 continue;
4667 }
4668
4669 if (tryzero != -1 &&
4670 (ip6._S6_un._S6_u8[i] != 0 ||
4671 i == sizeof (struct in6_addr) - 1)) {
4672
4673 if (i - tryzero <= numzero) {
4674 tryzero = -1;
4675 continue;
4676 }
4677
4678 firstzero = tryzero;
4679 numzero = i - i % 2 - tryzero;
4680 tryzero = -1;
4681
4682 if (ip6._S6_un._S6_u8[i] == 0 &&
4683 i == sizeof (struct in6_addr) - 1)
4684 numzero += 2;
4685 }
4686 }
4687 ASSERT(firstzero + numzero <= sizeof (struct in6_addr));
4688
4689 /*
4690 * Check for an IPv4 embedded address.
4691 */
4692 v6end = sizeof (struct in6_addr) - 2;
4693 if (IN6_IS_ADDR_V4MAPPED(&ip6) ||
4694 IN6_IS_ADDR_V4COMPAT(&ip6)) {
4695 for (i = sizeof (struct in6_addr) - 1;
4696 i >= DTRACE_V4MAPPED_OFFSET; i--) {
4697 ASSERT(end >= base);
4698
4699 val = ip6._S6_un._S6_u8[i];
4700
4701 if (val == 0) {
4702 *end-- = '0';
4703 } else {
4704 for (; val; val /= 10) {
4705 *end-- = '0' + val % 10;
4706 }
4707 }
4708
4709 if (i > DTRACE_V4MAPPED_OFFSET)
4710 *end-- = '.';
4711 }
4712
4713 if (subr == DIF_SUBR_INET_NTOA6)
4714 goto inetout;
4715
4716 /*
4717 * Set v6end to skip the IPv4 address that
4718 * we have already stringified.
4719 */
4720 v6end = 10;
4721 }
4722
4723 /*
4724 * Build the IPv6 string by working through the
4725 * address in reverse.
4726 */
4727 for (i = v6end; i >= 0; i -= 2) {
4728 ASSERT(end >= base);
4729
4730 if (i == firstzero + numzero - 2) {
4731 *end-- = ':';
4732 *end-- = ':';
4733 i -= numzero - 2;
4734 continue;
4735 }
4736
4737 if (i < 14 && i != firstzero - 2)
4738 *end-- = ':';
4739
4740 val = (ip6._S6_un._S6_u8[i] << 8) +
4741 ip6._S6_un._S6_u8[i + 1];
4742
4743 if (val == 0) {
4744 *end-- = '0';
4745 } else {
4746 for (; val; val /= 16) {
4747 *end-- = digits[val % 16];
4748 }
4749 }
4750 }
4751 ASSERT(end + 1 >= base);
4752
4753 } else {
4754 /*
4755 * The user didn't use AH_INET or AH_INET6.
4756 */
4757 DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP);
4758 regs[rd] = NULL;
4759 break;
4760 }
4761
4762 inetout: regs[rd] = (uintptr_t)end + 1;
4763 mstate->dtms_scratch_ptr += size;
4764 break;
4765 }
4766
4767 }
4768 }
4769
4770 /*
4771 * Emulate the execution of DTrace IR instructions specified by the given
4772 * DIF object. This function is deliberately void of assertions as all of
4773 * the necessary checks are handled by a call to dtrace_difo_validate().
4774 */
4775 static uint64_t
4776 dtrace_dif_emulate(dtrace_difo_t *difo, dtrace_mstate_t *mstate,
4777 dtrace_vstate_t *vstate, dtrace_state_t *state)
4778 {
4779 const dif_instr_t *text = difo->dtdo_buf;
4780 const uint_t textlen = difo->dtdo_len;
4781 const char *strtab = difo->dtdo_strtab;
4782 const uint64_t *inttab = difo->dtdo_inttab;
4783
4784 uint64_t rval = 0;
4785 dtrace_statvar_t *svar;
4786 dtrace_dstate_t *dstate = &vstate->dtvs_dynvars;
4787 dtrace_difv_t *v;
4788 volatile uint16_t *flags = &cpu_core[CPU->cpu_id].cpuc_dtrace_flags;
4789 volatile uintptr_t *illval = &cpu_core[CPU->cpu_id].cpuc_dtrace_illval;
4790
4791 dtrace_key_t tupregs[DIF_DTR_NREGS + 2]; /* +2 for thread and id */
4792 uint64_t regs[DIF_DIR_NREGS];
4793 uint64_t *tmp;
4794
4795 uint8_t cc_n = 0, cc_z = 0, cc_v = 0, cc_c = 0;
4796 int64_t cc_r;
4797 uint_t pc = 0, id, opc;
4798 uint8_t ttop = 0;
4799 dif_instr_t instr;
4800 uint_t r1, r2, rd;
4801
4802 /*
4803 * We stash the current DIF object into the machine state: we need it
4804 * for subsequent access checking.
4805 */
4806 mstate->dtms_difo = difo;
4807
4808 regs[DIF_REG_R0] = 0; /* %r0 is fixed at zero */
4809
4810 while (pc < textlen && !(*flags & CPU_DTRACE_FAULT)) {
4811 opc = pc;
4812
4813 instr = text[pc++];
4814 r1 = DIF_INSTR_R1(instr);
4815 r2 = DIF_INSTR_R2(instr);
4816 rd = DIF_INSTR_RD(instr);
4817
4818 switch (DIF_INSTR_OP(instr)) {
4819 case DIF_OP_OR:
4820 regs[rd] = regs[r1] | regs[r2];
4821 break;
4822 case DIF_OP_XOR:
4823 regs[rd] = regs[r1] ^ regs[r2];
4824 break;
4825 case DIF_OP_AND:
4826 regs[rd] = regs[r1] & regs[r2];
4827 break;
4828 case DIF_OP_SLL:
4829 regs[rd] = regs[r1] << regs[r2];
4830 break;
4831 case DIF_OP_SRL:
4832 regs[rd] = regs[r1] >> regs[r2];
4833 break;
4834 case DIF_OP_SUB:
4835 regs[rd] = regs[r1] - regs[r2];
4836 break;
4837 case DIF_OP_ADD:
4838 regs[rd] = regs[r1] + regs[r2];
4839 break;
4840 case DIF_OP_MUL:
4841 regs[rd] = regs[r1] * regs[r2];
4842 break;
4843 case DIF_OP_SDIV:
4844 if (regs[r2] == 0) {
4845 regs[rd] = 0;
4846 *flags |= CPU_DTRACE_DIVZERO;
4847 } else {
4848 regs[rd] = (int64_t)regs[r1] /
4849 (int64_t)regs[r2];
4850 }
4851 break;
4852
4853 case DIF_OP_UDIV:
4854 if (regs[r2] == 0) {
4855 regs[rd] = 0;
4856 *flags |= CPU_DTRACE_DIVZERO;
4857 } else {
4858 regs[rd] = regs[r1] / regs[r2];
4859 }
4860 break;
4861
4862 case DIF_OP_SREM:
4863 if (regs[r2] == 0) {
4864 regs[rd] = 0;
4865 *flags |= CPU_DTRACE_DIVZERO;
4866 } else {
4867 regs[rd] = (int64_t)regs[r1] %
4868 (int64_t)regs[r2];
4869 }
4870 break;
4871
4872 case DIF_OP_UREM:
4873 if (regs[r2] == 0) {
4874 regs[rd] = 0;
4875 *flags |= CPU_DTRACE_DIVZERO;
4876 } else {
4877 regs[rd] = regs[r1] % regs[r2];
4878 }
4879 break;
4880
4881 case DIF_OP_NOT:
4882 regs[rd] = ~regs[r1];
4883 break;
4884 case DIF_OP_MOV:
4885 regs[rd] = regs[r1];
4886 break;
4887 case DIF_OP_CMP:
4888 cc_r = regs[r1] - regs[r2];
4889 cc_n = cc_r < 0;
4890 cc_z = cc_r == 0;
4891 cc_v = 0;
4892 cc_c = regs[r1] < regs[r2];
4893 break;
4894 case DIF_OP_TST:
4895 cc_n = cc_v = cc_c = 0;
4896 cc_z = regs[r1] == 0;
4897 break;
4898 case DIF_OP_BA:
4899 pc = DIF_INSTR_LABEL(instr);
4900 break;
4901 case DIF_OP_BE:
4902 if (cc_z)
4903 pc = DIF_INSTR_LABEL(instr);
4904 break;
4905 case DIF_OP_BNE:
4906 if (cc_z == 0)
4907 pc = DIF_INSTR_LABEL(instr);
4908 break;
4909 case DIF_OP_BG:
4910 if ((cc_z | (cc_n ^ cc_v)) == 0)
4911 pc = DIF_INSTR_LABEL(instr);
4912 break;
4913 case DIF_OP_BGU:
4914 if ((cc_c | cc_z) == 0)
4915 pc = DIF_INSTR_LABEL(instr);
4916 break;
4917 case DIF_OP_BGE:
4918 if ((cc_n ^ cc_v) == 0)
4919 pc = DIF_INSTR_LABEL(instr);
4920 break;
4921 case DIF_OP_BGEU:
4922 if (cc_c == 0)
4923 pc = DIF_INSTR_LABEL(instr);
4924 break;
4925 case DIF_OP_BL:
4926 if (cc_n ^ cc_v)
4927 pc = DIF_INSTR_LABEL(instr);
4928 break;
4929 case DIF_OP_BLU:
4930 if (cc_c)
4931 pc = DIF_INSTR_LABEL(instr);
4932 break;
4933 case DIF_OP_BLE:
4934 if (cc_z | (cc_n ^ cc_v))
4935 pc = DIF_INSTR_LABEL(instr);
4936 break;
4937 case DIF_OP_BLEU:
4938 if (cc_c | cc_z)
4939 pc = DIF_INSTR_LABEL(instr);
4940 break;
4941 case DIF_OP_RLDSB:
4942 if (!dtrace_canstore(regs[r1], 1, mstate, vstate)) {
4943 *flags |= CPU_DTRACE_KPRIV;
4944 *illval = regs[r1];
4945 break;
4946 }
4947 /*FALLTHROUGH*/
4948 case DIF_OP_LDSB:
4949 regs[rd] = (int8_t)dtrace_load8(regs[r1]);
4950 break;
4951 case DIF_OP_RLDSH:
4952 if (!dtrace_canstore(regs[r1], 2, mstate, vstate)) {
4953 *flags |= CPU_DTRACE_KPRIV;
4954 *illval = regs[r1];
4955 break;
4956 }
4957 /*FALLTHROUGH*/
4958 case DIF_OP_LDSH:
4959 regs[rd] = (int16_t)dtrace_load16(regs[r1]);
4960 break;
4961 case DIF_OP_RLDSW:
4962 if (!dtrace_canstore(regs[r1], 4, mstate, vstate)) {
4963 *flags |= CPU_DTRACE_KPRIV;
4964 *illval = regs[r1];
4965 break;
4966 }
4967 /*FALLTHROUGH*/
4968 case DIF_OP_LDSW:
4969 regs[rd] = (int32_t)dtrace_load32(regs[r1]);
4970 break;
4971 case DIF_OP_RLDUB:
4972 if (!dtrace_canstore(regs[r1], 1, mstate, vstate)) {
4973 *flags |= CPU_DTRACE_KPRIV;
4974 *illval = regs[r1];
4975 break;
4976 }
4977 /*FALLTHROUGH*/
4978 case DIF_OP_LDUB:
4979 regs[rd] = dtrace_load8(regs[r1]);
4980 break;
4981 case DIF_OP_RLDUH:
4982 if (!dtrace_canstore(regs[r1], 2, mstate, vstate)) {
4983 *flags |= CPU_DTRACE_KPRIV;
4984 *illval = regs[r1];
4985 break;
4986 }
4987 /*FALLTHROUGH*/
4988 case DIF_OP_LDUH:
4989 regs[rd] = dtrace_load16(regs[r1]);
4990 break;
4991 case DIF_OP_RLDUW:
4992 if (!dtrace_canstore(regs[r1], 4, mstate, vstate)) {
4993 *flags |= CPU_DTRACE_KPRIV;
4994 *illval = regs[r1];
4995 break;
4996 }
4997 /*FALLTHROUGH*/
4998 case DIF_OP_LDUW:
4999 regs[rd] = dtrace_load32(regs[r1]);
5000 break;
5001 case DIF_OP_RLDX:
5002 if (!dtrace_canstore(regs[r1], 8, mstate, vstate)) {
5003 *flags |= CPU_DTRACE_KPRIV;
5004 *illval = regs[r1];
5005 break;
5006 }
5007 /*FALLTHROUGH*/
5008 case DIF_OP_LDX:
5009 regs[rd] = dtrace_load64(regs[r1]);
5010 break;
5011 case DIF_OP_ULDSB:
5012 regs[rd] = (int8_t)
5013 dtrace_fuword8((void *)(uintptr_t)regs[r1]);
5014 break;
5015 case DIF_OP_ULDSH:
5016 regs[rd] = (int16_t)
5017 dtrace_fuword16((void *)(uintptr_t)regs[r1]);
5018 break;
5019 case DIF_OP_ULDSW:
5020 regs[rd] = (int32_t)
5021 dtrace_fuword32((void *)(uintptr_t)regs[r1]);
5022 break;
5023 case DIF_OP_ULDUB:
5024 regs[rd] =
5025 dtrace_fuword8((void *)(uintptr_t)regs[r1]);
5026 break;
5027 case DIF_OP_ULDUH:
5028 regs[rd] =
5029 dtrace_fuword16((void *)(uintptr_t)regs[r1]);
5030 break;
5031 case DIF_OP_ULDUW:
5032 regs[rd] =
5033 dtrace_fuword32((void *)(uintptr_t)regs[r1]);
5034 break;
5035 case DIF_OP_ULDX:
5036 regs[rd] =
5037 dtrace_fuword64((void *)(uintptr_t)regs[r1]);
5038 break;
5039 case DIF_OP_RET:
5040 rval = regs[rd];
5041 pc = textlen;
5042 break;
5043 case DIF_OP_NOP:
5044 break;
5045 case DIF_OP_SETX:
5046 regs[rd] = inttab[DIF_INSTR_INTEGER(instr)];
5047 break;
5048 case DIF_OP_SETS:
5049 regs[rd] = (uint64_t)(uintptr_t)
5050 (strtab + DIF_INSTR_STRING(instr));
5051 break;
5052 case DIF_OP_SCMP: {
5053 size_t sz = state->dts_options[DTRACEOPT_STRSIZE];
5054 uintptr_t s1 = regs[r1];
5055 uintptr_t s2 = regs[r2];
5056
5057 if (s1 != NULL &&
5058 !dtrace_strcanload(s1, sz, mstate, vstate))
5059 break;
5060 if (s2 != NULL &&
5061 !dtrace_strcanload(s2, sz, mstate, vstate))
5062 break;
5063
5064 cc_r = dtrace_strncmp((char *)s1, (char *)s2, sz);
5065
5066 cc_n = cc_r < 0;
5067 cc_z = cc_r == 0;
5068 cc_v = cc_c = 0;
5069 break;
5070 }
5071 case DIF_OP_LDGA:
5072 regs[rd] = dtrace_dif_variable(mstate, state,
5073 r1, regs[r2]);
5074 break;
5075 case DIF_OP_LDGS:
5076 id = DIF_INSTR_VAR(instr);
5077
5078 if (id >= DIF_VAR_OTHER_UBASE) {
5079 uintptr_t a;
5080
5081 id -= DIF_VAR_OTHER_UBASE;
5082 svar = vstate->dtvs_globals[id];
5083 ASSERT(svar != NULL);
5084 v = &svar->dtsv_var;
5085
5086 if (!(v->dtdv_type.dtdt_flags & DIF_TF_BYREF)) {
5087 regs[rd] = svar->dtsv_data;
5088 break;
5089 }
5090
5091 a = (uintptr_t)svar->dtsv_data;
5092
5093 if (*(uint8_t *)a == UINT8_MAX) {
5094 /*
5095 * If the 0th byte is set to UINT8_MAX
5096 * then this is to be treated as a
5097 * reference to a NULL variable.
5098 */
5099 regs[rd] = NULL;
5100 } else {
5101 regs[rd] = a + sizeof (uint64_t);
5102 }
5103
5104 break;
5105 }
5106
5107 regs[rd] = dtrace_dif_variable(mstate, state, id, 0);
5108 break;
5109
5110 case DIF_OP_STGS:
5111 id = DIF_INSTR_VAR(instr);
5112
5113 ASSERT(id >= DIF_VAR_OTHER_UBASE);
5114 id -= DIF_VAR_OTHER_UBASE;
5115
5116 svar = vstate->dtvs_globals[id];
5117 ASSERT(svar != NULL);
5118 v = &svar->dtsv_var;
5119
5120 if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) {
5121 uintptr_t a = (uintptr_t)svar->dtsv_data;
5122
5123 ASSERT(a != NULL);
5124 ASSERT(svar->dtsv_size != 0);
5125
5126 if (regs[rd] == NULL) {
5127 *(uint8_t *)a = UINT8_MAX;
5128 break;
5129 } else {
5130 *(uint8_t *)a = 0;
5131 a += sizeof (uint64_t);
5132 }
5133 if (!dtrace_vcanload(
5134 (void *)(uintptr_t)regs[rd], &v->dtdv_type,
5135 mstate, vstate))
5136 break;
5137
5138 dtrace_vcopy((void *)(uintptr_t)regs[rd],
5139 (void *)a, &v->dtdv_type);
5140 break;
5141 }
5142
5143 svar->dtsv_data = regs[rd];
5144 break;
5145
5146 case DIF_OP_LDTA:
5147 /*
5148 * There are no DTrace built-in thread-local arrays at
5149 * present. This opcode is saved for future work.
5150 */
5151 *flags |= CPU_DTRACE_ILLOP;
5152 regs[rd] = 0;
5153 break;
5154
5155 case DIF_OP_LDLS:
5156 id = DIF_INSTR_VAR(instr);
5157
5158 if (id < DIF_VAR_OTHER_UBASE) {
5159 /*
5160 * For now, this has no meaning.
5161 */
5162 regs[rd] = 0;
5163 break;
5164 }
5165
5166 id -= DIF_VAR_OTHER_UBASE;
5167
5168 ASSERT(id < vstate->dtvs_nlocals);
5169 ASSERT(vstate->dtvs_locals != NULL);
5170
5171 svar = vstate->dtvs_locals[id];
5172 ASSERT(svar != NULL);
5173 v = &svar->dtsv_var;
5174
5175 if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) {
5176 uintptr_t a = (uintptr_t)svar->dtsv_data;
5177 size_t sz = v->dtdv_type.dtdt_size;
5178
5179 sz += sizeof (uint64_t);
5180 ASSERT(svar->dtsv_size == NCPU * sz);
5181 a += CPU->cpu_id * sz;
5182
5183 if (*(uint8_t *)a == UINT8_MAX) {
5184 /*
5185 * If the 0th byte is set to UINT8_MAX
5186 * then this is to be treated as a
5187 * reference to a NULL variable.
5188 */
5189 regs[rd] = NULL;
5190 } else {
5191 regs[rd] = a + sizeof (uint64_t);
5192 }
5193
5194 break;
5195 }
5196
5197 ASSERT(svar->dtsv_size == NCPU * sizeof (uint64_t));
5198 tmp = (uint64_t *)(uintptr_t)svar->dtsv_data;
5199 regs[rd] = tmp[CPU->cpu_id];
5200 break;
5201
5202 case DIF_OP_STLS:
5203 id = DIF_INSTR_VAR(instr);
5204
5205 ASSERT(id >= DIF_VAR_OTHER_UBASE);
5206 id -= DIF_VAR_OTHER_UBASE;
5207 ASSERT(id < vstate->dtvs_nlocals);
5208
5209 ASSERT(vstate->dtvs_locals != NULL);
5210 svar = vstate->dtvs_locals[id];
5211 ASSERT(svar != NULL);
5212 v = &svar->dtsv_var;
5213
5214 if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) {
5215 uintptr_t a = (uintptr_t)svar->dtsv_data;
5216 size_t sz = v->dtdv_type.dtdt_size;
5217
5218 sz += sizeof (uint64_t);
5219 ASSERT(svar->dtsv_size == NCPU * sz);
5220 a += CPU->cpu_id * sz;
5221
5222 if (regs[rd] == NULL) {
5223 *(uint8_t *)a = UINT8_MAX;
5224 break;
5225 } else {
5226 *(uint8_t *)a = 0;
5227 a += sizeof (uint64_t);
5228 }
5229
5230 if (!dtrace_vcanload(
5231 (void *)(uintptr_t)regs[rd], &v->dtdv_type,
5232 mstate, vstate))
5233 break;
5234
5235 dtrace_vcopy((void *)(uintptr_t)regs[rd],
5236 (void *)a, &v->dtdv_type);
5237 break;
5238 }
5239
5240 ASSERT(svar->dtsv_size == NCPU * sizeof (uint64_t));
5241 tmp = (uint64_t *)(uintptr_t)svar->dtsv_data;
5242 tmp[CPU->cpu_id] = regs[rd];
5243 break;
5244
5245 case DIF_OP_LDTS: {
5246 dtrace_dynvar_t *dvar;
5247 dtrace_key_t *key;
5248
5249 id = DIF_INSTR_VAR(instr);
5250 ASSERT(id >= DIF_VAR_OTHER_UBASE);
5251 id -= DIF_VAR_OTHER_UBASE;
5252 v = &vstate->dtvs_tlocals[id];
5253
5254 key = &tupregs[DIF_DTR_NREGS];
5255 key[0].dttk_value = (uint64_t)id;
5256 key[0].dttk_size = 0;
5257 DTRACE_TLS_THRKEY(key[1].dttk_value);
5258 key[1].dttk_size = 0;
5259
5260 dvar = dtrace_dynvar(dstate, 2, key,
5261 sizeof (uint64_t), DTRACE_DYNVAR_NOALLOC,
5262 mstate, vstate);
5263
5264 if (dvar == NULL) {
5265 regs[rd] = 0;
5266 break;
5267 }
5268
5269 if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) {
5270 regs[rd] = (uint64_t)(uintptr_t)dvar->dtdv_data;
5271 } else {
5272 regs[rd] = *((uint64_t *)dvar->dtdv_data);
5273 }
5274
5275 break;
5276 }
5277
5278 case DIF_OP_STTS: {
5279 dtrace_dynvar_t *dvar;
5280 dtrace_key_t *key;
5281
5282 id = DIF_INSTR_VAR(instr);
5283 ASSERT(id >= DIF_VAR_OTHER_UBASE);
5284 id -= DIF_VAR_OTHER_UBASE;
5285
5286 key = &tupregs[DIF_DTR_NREGS];
5287 key[0].dttk_value = (uint64_t)id;
5288 key[0].dttk_size = 0;
5289 DTRACE_TLS_THRKEY(key[1].dttk_value);
5290 key[1].dttk_size = 0;
5291 v = &vstate->dtvs_tlocals[id];
5292
5293 dvar = dtrace_dynvar(dstate, 2, key,
5294 v->dtdv_type.dtdt_size > sizeof (uint64_t) ?
5295 v->dtdv_type.dtdt_size : sizeof (uint64_t),
5296 regs[rd] ? DTRACE_DYNVAR_ALLOC :
5297 DTRACE_DYNVAR_DEALLOC, mstate, vstate);
5298
5299 /*
5300 * Given that we're storing to thread-local data,
5301 * we need to flush our predicate cache.
5302 */
5303 curthread->t_predcache = NULL;
5304
5305 if (dvar == NULL)
5306 break;
5307
5308 if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) {
5309 if (!dtrace_vcanload(
5310 (void *)(uintptr_t)regs[rd],
5311 &v->dtdv_type, mstate, vstate))
5312 break;
5313
5314 dtrace_vcopy((void *)(uintptr_t)regs[rd],
5315 dvar->dtdv_data, &v->dtdv_type);
5316 } else {
5317 *((uint64_t *)dvar->dtdv_data) = regs[rd];
5318 }
5319
5320 break;
5321 }
5322
5323 case DIF_OP_SRA:
5324 regs[rd] = (int64_t)regs[r1] >> regs[r2];
5325 break;
5326
5327 case DIF_OP_CALL:
5328 dtrace_dif_subr(DIF_INSTR_SUBR(instr), rd,
5329 regs, tupregs, ttop, mstate, state);
5330 break;
5331
5332 case DIF_OP_PUSHTR:
5333 if (ttop == DIF_DTR_NREGS) {
5334 *flags |= CPU_DTRACE_TUPOFLOW;
5335 break;
5336 }
5337
5338 if (r1 == DIF_TYPE_STRING) {
5339 /*
5340 * If this is a string type and the size is 0,
5341 * we'll use the system-wide default string
5342 * size. Note that we are _not_ looking at
5343 * the value of the DTRACEOPT_STRSIZE option;
5344 * had this been set, we would expect to have
5345 * a non-zero size value in the "pushtr".
5346 */
5347 tupregs[ttop].dttk_size =
5348 dtrace_strlen((char *)(uintptr_t)regs[rd],
5349 regs[r2] ? regs[r2] :
5350 dtrace_strsize_default) + 1;
5351 } else {
5352 tupregs[ttop].dttk_size = regs[r2];
5353 }
5354
5355 tupregs[ttop++].dttk_value = regs[rd];
5356 break;
5357
5358 case DIF_OP_PUSHTV:
5359 if (ttop == DIF_DTR_NREGS) {
5360 *flags |= CPU_DTRACE_TUPOFLOW;
5361 break;
5362 }
5363
5364 tupregs[ttop].dttk_value = regs[rd];
5365 tupregs[ttop++].dttk_size = 0;
5366 break;
5367
5368 case DIF_OP_POPTS:
5369 if (ttop != 0)
5370 ttop--;
5371 break;
5372
5373 case DIF_OP_FLUSHTS:
5374 ttop = 0;
5375 break;
5376
5377 case DIF_OP_LDGAA:
5378 case DIF_OP_LDTAA: {
5379 dtrace_dynvar_t *dvar;
5380 dtrace_key_t *key = tupregs;
5381 uint_t nkeys = ttop;
5382
5383 id = DIF_INSTR_VAR(instr);
5384 ASSERT(id >= DIF_VAR_OTHER_UBASE);
5385 id -= DIF_VAR_OTHER_UBASE;
5386
5387 key[nkeys].dttk_value = (uint64_t)id;
5388 key[nkeys++].dttk_size = 0;
5389
5390 if (DIF_INSTR_OP(instr) == DIF_OP_LDTAA) {
5391 DTRACE_TLS_THRKEY(key[nkeys].dttk_value);
5392 key[nkeys++].dttk_size = 0;
5393 v = &vstate->dtvs_tlocals[id];
5394 } else {
5395 v = &vstate->dtvs_globals[id]->dtsv_var;
5396 }
5397
5398 dvar = dtrace_dynvar(dstate, nkeys, key,
5399 v->dtdv_type.dtdt_size > sizeof (uint64_t) ?
5400 v->dtdv_type.dtdt_size : sizeof (uint64_t),
5401 DTRACE_DYNVAR_NOALLOC, mstate, vstate);
5402
5403 if (dvar == NULL) {
5404 regs[rd] = 0;
5405 break;
5406 }
5407
5408 if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) {
5409 regs[rd] = (uint64_t)(uintptr_t)dvar->dtdv_data;
5410 } else {
5411 regs[rd] = *((uint64_t *)dvar->dtdv_data);
5412 }
5413
5414 break;
5415 }
5416
5417 case DIF_OP_STGAA:
5418 case DIF_OP_STTAA: {
5419 dtrace_dynvar_t *dvar;
5420 dtrace_key_t *key = tupregs;
5421 uint_t nkeys = ttop;
5422
5423 id = DIF_INSTR_VAR(instr);
5424 ASSERT(id >= DIF_VAR_OTHER_UBASE);
5425 id -= DIF_VAR_OTHER_UBASE;
5426
5427 key[nkeys].dttk_value = (uint64_t)id;
5428 key[nkeys++].dttk_size = 0;
5429
5430 if (DIF_INSTR_OP(instr) == DIF_OP_STTAA) {
5431 DTRACE_TLS_THRKEY(key[nkeys].dttk_value);
5432 key[nkeys++].dttk_size = 0;
5433 v = &vstate->dtvs_tlocals[id];
5434 } else {
5435 v = &vstate->dtvs_globals[id]->dtsv_var;
5436 }
5437
5438 dvar = dtrace_dynvar(dstate, nkeys, key,
5439 v->dtdv_type.dtdt_size > sizeof (uint64_t) ?
5440 v->dtdv_type.dtdt_size : sizeof (uint64_t),
5441 regs[rd] ? DTRACE_DYNVAR_ALLOC :
5442 DTRACE_DYNVAR_DEALLOC, mstate, vstate);
5443
5444 if (dvar == NULL)
5445 break;
5446
5447 if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) {
5448 if (!dtrace_vcanload(
5449 (void *)(uintptr_t)regs[rd], &v->dtdv_type,
5450 mstate, vstate))
5451 break;
5452
5453 dtrace_vcopy((void *)(uintptr_t)regs[rd],
5454 dvar->dtdv_data, &v->dtdv_type);
5455 } else {
5456 *((uint64_t *)dvar->dtdv_data) = regs[rd];
5457 }
5458
5459 break;
5460 }
5461
5462 case DIF_OP_ALLOCS: {
5463 uintptr_t ptr = P2ROUNDUP(mstate->dtms_scratch_ptr, 8);
5464 size_t size = ptr - mstate->dtms_scratch_ptr + regs[r1];
5465
5466 /*
5467 * Rounding up the user allocation size could have
5468 * overflowed large, bogus allocations (like -1ULL) to
5469 * 0.
5470 */
5471 if (size < regs[r1] ||
5472 !DTRACE_INSCRATCH(mstate, size)) {
5473 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
5474 regs[rd] = NULL;
5475 break;
5476 }
5477
5478 dtrace_bzero((void *) mstate->dtms_scratch_ptr, size);
5479 mstate->dtms_scratch_ptr += size;
5480 regs[rd] = ptr;
5481 break;
5482 }
5483
5484 case DIF_OP_COPYS:
5485 if (!dtrace_canstore(regs[rd], regs[r2],
5486 mstate, vstate)) {
5487 *flags |= CPU_DTRACE_BADADDR;
5488 *illval = regs[rd];
5489 break;
5490 }
5491
5492 if (!dtrace_canload(regs[r1], regs[r2], mstate, vstate))
5493 break;
5494
5495 dtrace_bcopy((void *)(uintptr_t)regs[r1],
5496 (void *)(uintptr_t)regs[rd], (size_t)regs[r2]);
5497 break;
5498
5499 case DIF_OP_STB:
5500 if (!dtrace_canstore(regs[rd], 1, mstate, vstate)) {
5501 *flags |= CPU_DTRACE_BADADDR;
5502 *illval = regs[rd];
5503 break;
5504 }
5505 *((uint8_t *)(uintptr_t)regs[rd]) = (uint8_t)regs[r1];
5506 break;
5507
5508 case DIF_OP_STH:
5509 if (!dtrace_canstore(regs[rd], 2, mstate, vstate)) {
5510 *flags |= CPU_DTRACE_BADADDR;
5511 *illval = regs[rd];
5512 break;
5513 }
5514 if (regs[rd] & 1) {
5515 *flags |= CPU_DTRACE_BADALIGN;
5516 *illval = regs[rd];
5517 break;
5518 }
5519 *((uint16_t *)(uintptr_t)regs[rd]) = (uint16_t)regs[r1];
5520 break;
5521
5522 case DIF_OP_STW:
5523 if (!dtrace_canstore(regs[rd], 4, mstate, vstate)) {
5524 *flags |= CPU_DTRACE_BADADDR;
5525 *illval = regs[rd];
5526 break;
5527 }
5528 if (regs[rd] & 3) {
5529 *flags |= CPU_DTRACE_BADALIGN;
5530 *illval = regs[rd];
5531 break;
5532 }
5533 *((uint32_t *)(uintptr_t)regs[rd]) = (uint32_t)regs[r1];
5534 break;
5535
5536 case DIF_OP_STX:
5537 if (!dtrace_canstore(regs[rd], 8, mstate, vstate)) {
5538 *flags |= CPU_DTRACE_BADADDR;
5539 *illval = regs[rd];
5540 break;
5541 }
5542 if (regs[rd] & 7) {
5543 *flags |= CPU_DTRACE_BADALIGN;
5544 *illval = regs[rd];
5545 break;
5546 }
5547 *((uint64_t *)(uintptr_t)regs[rd]) = regs[r1];
5548 break;
5549 }
5550 }
5551
5552 if (!(*flags & CPU_DTRACE_FAULT))
5553 return (rval);
5554
5555 mstate->dtms_fltoffs = opc * sizeof (dif_instr_t);
5556 mstate->dtms_present |= DTRACE_MSTATE_FLTOFFS;
5557
5558 return (0);
5559 }
5560
5561 static void
5562 dtrace_action_breakpoint(dtrace_ecb_t *ecb)
5563 {
5564 dtrace_probe_t *probe = ecb->dte_probe;
5565 dtrace_provider_t *prov = probe->dtpr_provider;
5566 char c[DTRACE_FULLNAMELEN + 80], *str;
5567 char *msg = "dtrace: breakpoint action at probe ";
5568 char *ecbmsg = " (ecb ";
5569 uintptr_t mask = (0xf << (sizeof (uintptr_t) * NBBY / 4));
5570 uintptr_t val = (uintptr_t)ecb;
5571 int shift = (sizeof (uintptr_t) * NBBY) - 4, i = 0;
5572
5573 if (dtrace_destructive_disallow)
5574 return;
5575
5576 /*
5577 * It's impossible to be taking action on the NULL probe.
5578 */
5579 ASSERT(probe != NULL);
5580
5581 /*
5582 * This is a poor man's (destitute man's?) sprintf(): we want to
5583 * print the provider name, module name, function name and name of
5584 * the probe, along with the hex address of the ECB with the breakpoint
5585 * action -- all of which we must place in the character buffer by
5586 * hand.
5587 */
5588 while (*msg != '\0')
5589 c[i++] = *msg++;
5590
5591 for (str = prov->dtpv_name; *str != '\0'; str++)
5592 c[i++] = *str;
5593 c[i++] = ':';
5594
5595 for (str = probe->dtpr_mod; *str != '\0'; str++)
5596 c[i++] = *str;
5597 c[i++] = ':';
5598
5599 for (str = probe->dtpr_func; *str != '\0'; str++)
5600 c[i++] = *str;
5601 c[i++] = ':';
5602
5603 for (str = probe->dtpr_name; *str != '\0'; str++)
5604 c[i++] = *str;
5605
5606 while (*ecbmsg != '\0')
5607 c[i++] = *ecbmsg++;
5608
5609 while (shift >= 0) {
5610 mask = (uintptr_t)0xf << shift;
5611
5612 if (val >= ((uintptr_t)1 << shift))
5613 c[i++] = "0123456789abcdef"[(val & mask) >> shift];
5614 shift -= 4;
5615 }
5616
5617 c[i++] = ')';
5618 c[i] = '\0';
5619
5620 debug_enter(c);
5621 }
5622
5623 static void
5624 dtrace_action_panic(dtrace_ecb_t *ecb)
5625 {
5626 dtrace_probe_t *probe = ecb->dte_probe;
5627
5628 /*
5629 * It's impossible to be taking action on the NULL probe.
5630 */
5631 ASSERT(probe != NULL);
5632
5633 if (dtrace_destructive_disallow)
5634 return;
5635
5636 if (dtrace_panicked != NULL)
5637 return;
5638
5639 if (dtrace_casptr(&dtrace_panicked, NULL, curthread) != NULL)
5640 return;
5641
5642 /*
5643 * We won the right to panic. (We want to be sure that only one
5644 * thread calls panic() from dtrace_probe(), and that panic() is
5645 * called exactly once.)
5646 */
5647 dtrace_panic("dtrace: panic action at probe %s:%s:%s:%s (ecb %p)",
5648 probe->dtpr_provider->dtpv_name, probe->dtpr_mod,
5649 probe->dtpr_func, probe->dtpr_name, (void *)ecb);
5650 }
5651
5652 static void
5653 dtrace_action_raise(uint64_t sig)
5654 {
5655 if (dtrace_destructive_disallow)
5656 return;
5657
5658 if (sig >= NSIG) {
5659 DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP);
5660 return;
5661 }
5662
5663 /*
5664 * raise() has a queue depth of 1 -- we ignore all subsequent
5665 * invocations of the raise() action.
5666 */
5667 if (curthread->t_dtrace_sig == 0)
5668 curthread->t_dtrace_sig = (uint8_t)sig;
5669
5670 curthread->t_sig_check = 1;
5671 aston(curthread);
5672 }
5673
5674 static void
5675 dtrace_action_stop(void)
5676 {
5677 if (dtrace_destructive_disallow)
5678 return;
5679
5680 if (!curthread->t_dtrace_stop) {
5681 curthread->t_dtrace_stop = 1;
5682 curthread->t_sig_check = 1;
5683 aston(curthread);
5684 }
5685 }
5686
5687 static void
5688 dtrace_action_chill(dtrace_mstate_t *mstate, hrtime_t val)
5689 {
5690 hrtime_t now;
5691 volatile uint16_t *flags;
5692 cpu_t *cpu = CPU;
5693
5694 if (dtrace_destructive_disallow)
5695 return;
5696
5697 flags = (volatile uint16_t *)&cpu_core[cpu->cpu_id].cpuc_dtrace_flags;
5698
5699 now = dtrace_gethrtime();
5700
5701 if (now - cpu->cpu_dtrace_chillmark > dtrace_chill_interval) {
5702 /*
5703 * We need to advance the mark to the current time.
5704 */
5705 cpu->cpu_dtrace_chillmark = now;
5706 cpu->cpu_dtrace_chilled = 0;
5707 }
5708
5709 /*
5710 * Now check to see if the requested chill time would take us over
5711 * the maximum amount of time allowed in the chill interval. (Or
5712 * worse, if the calculation itself induces overflow.)
5713 */
5714 if (cpu->cpu_dtrace_chilled + val > dtrace_chill_max ||
5715 cpu->cpu_dtrace_chilled + val < cpu->cpu_dtrace_chilled) {
5716 *flags |= CPU_DTRACE_ILLOP;
5717 return;
5718 }
5719
5720 while (dtrace_gethrtime() - now < val)
5721 continue;
5722
5723 /*
5724 * Normally, we assure that the value of the variable "timestamp" does
5725 * not change within an ECB. The presence of chill() represents an
5726 * exception to this rule, however.
5727 */
5728 mstate->dtms_present &= ~DTRACE_MSTATE_TIMESTAMP;
5729 cpu->cpu_dtrace_chilled += val;
5730 }
5731
5732 static void
5733 dtrace_action_ustack(dtrace_mstate_t *mstate, dtrace_state_t *state,
5734 uint64_t *buf, uint64_t arg)
5735 {
5736 int nframes = DTRACE_USTACK_NFRAMES(arg);
5737 int strsize = DTRACE_USTACK_STRSIZE(arg);
5738 uint64_t *pcs = &buf[1], *fps;
5739 char *str = (char *)&pcs[nframes];
5740 int size, offs = 0, i, j;
5741 uintptr_t old = mstate->dtms_scratch_ptr, saved;
5742 uint16_t *flags = &cpu_core[CPU->cpu_id].cpuc_dtrace_flags;
5743 char *sym;
5744
5745 /*
5746 * Should be taking a faster path if string space has not been
5747 * allocated.
5748 */
5749 ASSERT(strsize != 0);
5750
5751 /*
5752 * We will first allocate some temporary space for the frame pointers.
5753 */
5754 fps = (uint64_t *)P2ROUNDUP(mstate->dtms_scratch_ptr, 8);
5755 size = (uintptr_t)fps - mstate->dtms_scratch_ptr +
5756 (nframes * sizeof (uint64_t));
5757
5758 if (!DTRACE_INSCRATCH(mstate, size)) {
5759 /*
5760 * Not enough room for our frame pointers -- need to indicate
5761 * that we ran out of scratch space.
5762 */
5763 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
5764 return;
5765 }
5766
5767 mstate->dtms_scratch_ptr += size;
5768 saved = mstate->dtms_scratch_ptr;
5769
5770 /*
5771 * Now get a stack with both program counters and frame pointers.
5772 */
5773 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
5774 dtrace_getufpstack(buf, fps, nframes + 1);
5775 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
5776
5777 /*
5778 * If that faulted, we're cooked.
5779 */
5780 if (*flags & CPU_DTRACE_FAULT)
5781 goto out;
5782
5783 /*
5784 * Now we want to walk up the stack, calling the USTACK helper. For
5785 * each iteration, we restore the scratch pointer.
5786 */
5787 for (i = 0; i < nframes; i++) {
5788 mstate->dtms_scratch_ptr = saved;
5789
5790 if (offs >= strsize)
5791 break;
5792
5793 sym = (char *)(uintptr_t)dtrace_helper(
5794 DTRACE_HELPER_ACTION_USTACK,
5795 mstate, state, pcs[i], fps[i]);
5796
5797 /*
5798 * If we faulted while running the helper, we're going to
5799 * clear the fault and null out the corresponding string.
5800 */
5801 if (*flags & CPU_DTRACE_FAULT) {
5802 *flags &= ~CPU_DTRACE_FAULT;
5803 str[offs++] = '\0';
5804 continue;
5805 }
5806
5807 if (sym == NULL) {
5808 str[offs++] = '\0';
5809 continue;
5810 }
5811
5812 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
5813
5814 /*
5815 * Now copy in the string that the helper returned to us.
5816 */
5817 for (j = 0; offs + j < strsize; j++) {
5818 if ((str[offs + j] = sym[j]) == '\0')
5819 break;
5820 }
5821
5822 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
5823
5824 offs += j + 1;
5825 }
5826
5827 if (offs >= strsize) {
5828 /*
5829 * If we didn't have room for all of the strings, we don't
5830 * abort processing -- this needn't be a fatal error -- but we
5831 * still want to increment a counter (dts_stkstroverflows) to
5832 * allow this condition to be warned about. (If this is from
5833 * a jstack() action, it is easily tuned via jstackstrsize.)
5834 */
5835 dtrace_error(&state->dts_stkstroverflows);
5836 }
5837
5838 while (offs < strsize)
5839 str[offs++] = '\0';
5840
5841 out:
5842 mstate->dtms_scratch_ptr = old;
5843 }
5844
5845 /*
5846 * If you're looking for the epicenter of DTrace, you just found it. This
5847 * is the function called by the provider to fire a probe -- from which all
5848 * subsequent probe-context DTrace activity emanates.
5849 */
5850 void
5851 dtrace_probe(dtrace_id_t id, uintptr_t arg0, uintptr_t arg1,
5852 uintptr_t arg2, uintptr_t arg3, uintptr_t arg4)
5853 {
5854 processorid_t cpuid;
5855 dtrace_icookie_t cookie;
5856 dtrace_probe_t *probe;
5857 dtrace_mstate_t mstate;
5858 dtrace_ecb_t *ecb;
5859 dtrace_action_t *act;
5860 intptr_t offs;
5861 size_t size;
5862 int vtime, onintr;
5863 volatile uint16_t *flags;
5864 hrtime_t now, end;
5865
5866 /*
5867 * Kick out immediately if this CPU is still being born (in which case
5868 * curthread will be set to -1) or the current thread can't allow
5869 * probes in its current context.
5870 */
5871 if (((uintptr_t)curthread & 1) || (curthread->t_flag & T_DONTDTRACE))
5872 return;
5873
5874 cookie = dtrace_interrupt_disable();
5875 probe = dtrace_probes[id - 1];
5876 cpuid = CPU->cpu_id;
5877 onintr = CPU_ON_INTR(CPU);
5878
5879 CPU->cpu_dtrace_probes++;
5880
5881 if (!onintr && probe->dtpr_predcache != DTRACE_CACHEIDNONE &&
5882 probe->dtpr_predcache == curthread->t_predcache) {
5883 /*
5884 * We have hit in the predicate cache; we know that
5885 * this predicate would evaluate to be false.
5886 */
5887 dtrace_interrupt_enable(cookie);
5888 return;
5889 }
5890
5891 if (panic_quiesce) {
5892 /*
5893 * We don't trace anything if we're panicking.
5894 */
5895 dtrace_interrupt_enable(cookie);
5896 return;
5897 }
5898
5899 now = dtrace_gethrtime();
5900 vtime = dtrace_vtime_references != 0;
5901
5902 if (vtime && curthread->t_dtrace_start)
5903 curthread->t_dtrace_vtime += now - curthread->t_dtrace_start;
5904
5905 mstate.dtms_difo = NULL;
5906 mstate.dtms_probe = probe;
5907 mstate.dtms_strtok = NULL;
5908 mstate.dtms_arg[0] = arg0;
5909 mstate.dtms_arg[1] = arg1;
5910 mstate.dtms_arg[2] = arg2;
5911 mstate.dtms_arg[3] = arg3;
5912 mstate.dtms_arg[4] = arg4;
5913
5914 flags = (volatile uint16_t *)&cpu_core[cpuid].cpuc_dtrace_flags;
5915
5916 for (ecb = probe->dtpr_ecb; ecb != NULL; ecb = ecb->dte_next) {
5917 dtrace_predicate_t *pred = ecb->dte_predicate;
5918 dtrace_state_t *state = ecb->dte_state;
5919 dtrace_buffer_t *buf = &state->dts_buffer[cpuid];
5920 dtrace_buffer_t *aggbuf = &state->dts_aggbuffer[cpuid];
5921 dtrace_vstate_t *vstate = &state->dts_vstate;
5922 dtrace_provider_t *prov = probe->dtpr_provider;
5923 uint64_t tracememsize = 0;
5924 int committed = 0;
5925 caddr_t tomax;
5926
5927 /*
5928 * A little subtlety with the following (seemingly innocuous)
5929 * declaration of the automatic 'val': by looking at the
5930 * code, you might think that it could be declared in the
5931 * action processing loop, below. (That is, it's only used in
5932 * the action processing loop.) However, it must be declared
5933 * out of that scope because in the case of DIF expression
5934 * arguments to aggregating actions, one iteration of the
5935 * action loop will use the last iteration's value.
5936 */
5937 #ifdef lint
5938 uint64_t val = 0;
5939 #else
5940 uint64_t val;
5941 #endif
5942
5943 mstate.dtms_present = DTRACE_MSTATE_ARGS | DTRACE_MSTATE_PROBE;
5944 mstate.dtms_access = DTRACE_ACCESS_ARGS | DTRACE_ACCESS_PROC;
5945 *flags &= ~CPU_DTRACE_ERROR;
5946
5947 if (prov == dtrace_provider) {
5948 /*
5949 * If dtrace itself is the provider of this probe,
5950 * we're only going to continue processing the ECB if
5951 * arg0 (the dtrace_state_t) is equal to the ECB's
5952 * creating state. (This prevents disjoint consumers
5953 * from seeing one another's metaprobes.)
5954 */
5955 if (arg0 != (uint64_t)(uintptr_t)state)
5956 continue;
5957 }
5958
5959 if (state->dts_activity != DTRACE_ACTIVITY_ACTIVE) {
5960 /*
5961 * We're not currently active. If our provider isn't
5962 * the dtrace pseudo provider, we're not interested.
5963 */
5964 if (prov != dtrace_provider)
5965 continue;
5966
5967 /*
5968 * Now we must further check if we are in the BEGIN
5969 * probe. If we are, we will only continue processing
5970 * if we're still in WARMUP -- if one BEGIN enabling
5971 * has invoked the exit() action, we don't want to
5972 * evaluate subsequent BEGIN enablings.
5973 */
5974 if (probe->dtpr_id == dtrace_probeid_begin &&
5975 state->dts_activity != DTRACE_ACTIVITY_WARMUP) {
5976 ASSERT(state->dts_activity ==
5977 DTRACE_ACTIVITY_DRAINING);
5978 continue;
5979 }
5980 }
5981
5982 if (ecb->dte_cond && !dtrace_priv_probe(state, &mstate, ecb))
5983 continue;
5984
5985 if (now - state->dts_alive > dtrace_deadman_timeout) {
5986 /*
5987 * We seem to be dead. Unless we (a) have kernel
5988 * destructive permissions (b) have explicitly enabled
5989 * destructive actions and (c) destructive actions have
5990 * not been disabled, we're going to transition into
5991 * the KILLED state, from which no further processing
5992 * on this state will be performed.
5993 */
5994 if (!dtrace_priv_kernel_destructive(state) ||
5995 !state->dts_cred.dcr_destructive ||
5996 dtrace_destructive_disallow) {
5997 void *activity = &state->dts_activity;
5998 dtrace_activity_t current;
5999
6000 do {
6001 current = state->dts_activity;
6002 } while (dtrace_cas32(activity, current,
6003 DTRACE_ACTIVITY_KILLED) != current);
6004
6005 continue;
6006 }
6007 }
6008
6009 if ((offs = dtrace_buffer_reserve(buf, ecb->dte_needed,
6010 ecb->dte_alignment, state, &mstate)) < 0)
6011 continue;
6012
6013 tomax = buf->dtb_tomax;
6014 ASSERT(tomax != NULL);
6015
6016 if (ecb->dte_size != 0) {
6017 dtrace_rechdr_t dtrh;
6018 if (!(mstate.dtms_present & DTRACE_MSTATE_TIMESTAMP)) {
6019 mstate.dtms_timestamp = dtrace_gethrtime();
6020 mstate.dtms_present |= DTRACE_MSTATE_TIMESTAMP;
6021 }
6022 ASSERT3U(ecb->dte_size, >=, sizeof (dtrace_rechdr_t));
6023 dtrh.dtrh_epid = ecb->dte_epid;
6024 DTRACE_RECORD_STORE_TIMESTAMP(&dtrh,
6025 mstate.dtms_timestamp);
6026 *((dtrace_rechdr_t *)(tomax + offs)) = dtrh;
6027 }
6028
6029 mstate.dtms_epid = ecb->dte_epid;
6030 mstate.dtms_present |= DTRACE_MSTATE_EPID;
6031
6032 if (state->dts_cred.dcr_visible & DTRACE_CRV_KERNEL)
6033 mstate.dtms_access |= DTRACE_ACCESS_KERNEL;
6034
6035 if (pred != NULL) {
6036 dtrace_difo_t *dp = pred->dtp_difo;
6037 int rval;
6038
6039 rval = dtrace_dif_emulate(dp, &mstate, vstate, state);
6040
6041 if (!(*flags & CPU_DTRACE_ERROR) && !rval) {
6042 dtrace_cacheid_t cid = probe->dtpr_predcache;
6043
6044 if (cid != DTRACE_CACHEIDNONE && !onintr) {
6045 /*
6046 * Update the predicate cache...
6047 */
6048 ASSERT(cid == pred->dtp_cacheid);
6049 curthread->t_predcache = cid;
6050 }
6051
6052 continue;
6053 }
6054 }
6055
6056 for (act = ecb->dte_action; !(*flags & CPU_DTRACE_ERROR) &&
6057 act != NULL; act = act->dta_next) {
6058 size_t valoffs;
6059 dtrace_difo_t *dp;
6060 dtrace_recdesc_t *rec = &act->dta_rec;
6061
6062 size = rec->dtrd_size;
6063 valoffs = offs + rec->dtrd_offset;
6064
6065 if (DTRACEACT_ISAGG(act->dta_kind)) {
6066 uint64_t v = 0xbad;
6067 dtrace_aggregation_t *agg;
6068
6069 agg = (dtrace_aggregation_t *)act;
6070
6071 if ((dp = act->dta_difo) != NULL)
6072 v = dtrace_dif_emulate(dp,
6073 &mstate, vstate, state);
6074
6075 if (*flags & CPU_DTRACE_ERROR)
6076 continue;
6077
6078 /*
6079 * Note that we always pass the expression
6080 * value from the previous iteration of the
6081 * action loop. This value will only be used
6082 * if there is an expression argument to the
6083 * aggregating action, denoted by the
6084 * dtag_hasarg field.
6085 */
6086 dtrace_aggregate(agg, buf,
6087 offs, aggbuf, v, val);
6088 continue;
6089 }
6090
6091 switch (act->dta_kind) {
6092 case DTRACEACT_STOP:
6093 if (dtrace_priv_proc_destructive(state,
6094 &mstate))
6095 dtrace_action_stop();
6096 continue;
6097
6098 case DTRACEACT_BREAKPOINT:
6099 if (dtrace_priv_kernel_destructive(state))
6100 dtrace_action_breakpoint(ecb);
6101 continue;
6102
6103 case DTRACEACT_PANIC:
6104 if (dtrace_priv_kernel_destructive(state))
6105 dtrace_action_panic(ecb);
6106 continue;
6107
6108 case DTRACEACT_STACK:
6109 if (!dtrace_priv_kernel(state))
6110 continue;
6111
6112 dtrace_getpcstack((pc_t *)(tomax + valoffs),
6113 size / sizeof (pc_t), probe->dtpr_aframes,
6114 DTRACE_ANCHORED(probe) ? NULL :
6115 (uint32_t *)arg0);
6116
6117 continue;
6118
6119 case DTRACEACT_JSTACK:
6120 case DTRACEACT_USTACK:
6121 if (!dtrace_priv_proc(state, &mstate))
6122 continue;
6123
6124 /*
6125 * See comment in DIF_VAR_PID.
6126 */
6127 if (DTRACE_ANCHORED(mstate.dtms_probe) &&
6128 CPU_ON_INTR(CPU)) {
6129 int depth = DTRACE_USTACK_NFRAMES(
6130 rec->dtrd_arg) + 1;
6131
6132 dtrace_bzero((void *)(tomax + valoffs),
6133 DTRACE_USTACK_STRSIZE(rec->dtrd_arg)
6134 + depth * sizeof (uint64_t));
6135
6136 continue;
6137 }
6138
6139 if (DTRACE_USTACK_STRSIZE(rec->dtrd_arg) != 0 &&
6140 curproc->p_dtrace_helpers != NULL) {
6141 /*
6142 * This is the slow path -- we have
6143 * allocated string space, and we're
6144 * getting the stack of a process that
6145 * has helpers. Call into a separate
6146 * routine to perform this processing.
6147 */
6148 dtrace_action_ustack(&mstate, state,
6149 (uint64_t *)(tomax + valoffs),
6150 rec->dtrd_arg);
6151 continue;
6152 }
6153
6154 /*
6155 * Clear the string space, since there's no
6156 * helper to do it for us.
6157 */
6158 if (DTRACE_USTACK_STRSIZE(rec->dtrd_arg) != 0) {
6159 int depth = DTRACE_USTACK_NFRAMES(
6160 rec->dtrd_arg);
6161 size_t strsize = DTRACE_USTACK_STRSIZE(
6162 rec->dtrd_arg);
6163 uint64_t *buf = (uint64_t *)(tomax +
6164 valoffs);
6165 void *strspace = &buf[depth + 1];
6166
6167 dtrace_bzero(strspace,
6168 MIN(depth, strsize));
6169 }
6170
6171 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
6172 dtrace_getupcstack((uint64_t *)
6173 (tomax + valoffs),
6174 DTRACE_USTACK_NFRAMES(rec->dtrd_arg) + 1);
6175 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
6176 continue;
6177
6178 default:
6179 break;
6180 }
6181
6182 dp = act->dta_difo;
6183 ASSERT(dp != NULL);
6184
6185 val = dtrace_dif_emulate(dp, &mstate, vstate, state);
6186
6187 if (*flags & CPU_DTRACE_ERROR)
6188 continue;
6189
6190 switch (act->dta_kind) {
6191 case DTRACEACT_SPECULATE: {
6192 dtrace_rechdr_t *dtrh;
6193
6194 ASSERT(buf == &state->dts_buffer[cpuid]);
6195 buf = dtrace_speculation_buffer(state,
6196 cpuid, val);
6197
6198 if (buf == NULL) {
6199 *flags |= CPU_DTRACE_DROP;
6200 continue;
6201 }
6202
6203 offs = dtrace_buffer_reserve(buf,
6204 ecb->dte_needed, ecb->dte_alignment,
6205 state, NULL);
6206
6207 if (offs < 0) {
6208 *flags |= CPU_DTRACE_DROP;
6209 continue;
6210 }
6211
6212 tomax = buf->dtb_tomax;
6213 ASSERT(tomax != NULL);
6214
6215 if (ecb->dte_size == 0)
6216 continue;
6217
6218 ASSERT3U(ecb->dte_size, >=,
6219 sizeof (dtrace_rechdr_t));
6220 dtrh = ((void *)(tomax + offs));
6221 dtrh->dtrh_epid = ecb->dte_epid;
6222 /*
6223 * When the speculation is committed, all of
6224 * the records in the speculative buffer will
6225 * have their timestamps set to the commit
6226 * time. Until then, it is set to a sentinel
6227 * value, for debugability.
6228 */
6229 DTRACE_RECORD_STORE_TIMESTAMP(dtrh, UINT64_MAX);
6230 continue;
6231 }
6232
6233 case DTRACEACT_CHILL:
6234 if (dtrace_priv_kernel_destructive(state))
6235 dtrace_action_chill(&mstate, val);
6236 continue;
6237
6238 case DTRACEACT_RAISE:
6239 if (dtrace_priv_proc_destructive(state,
6240 &mstate))
6241 dtrace_action_raise(val);
6242 continue;
6243
6244 case DTRACEACT_COMMIT:
6245 ASSERT(!committed);
6246
6247 /*
6248 * We need to commit our buffer state.
6249 */
6250 if (ecb->dte_size)
6251 buf->dtb_offset = offs + ecb->dte_size;
6252 buf = &state->dts_buffer[cpuid];
6253 dtrace_speculation_commit(state, cpuid, val);
6254 committed = 1;
6255 continue;
6256
6257 case DTRACEACT_DISCARD:
6258 dtrace_speculation_discard(state, cpuid, val);
6259 continue;
6260
6261 case DTRACEACT_DIFEXPR:
6262 case DTRACEACT_LIBACT:
6263 case DTRACEACT_PRINTF:
6264 case DTRACEACT_PRINTA:
6265 case DTRACEACT_SYSTEM:
6266 case DTRACEACT_FREOPEN:
6267 case DTRACEACT_TRACEMEM:
6268 break;
6269
6270 case DTRACEACT_TRACEMEM_DYNSIZE:
6271 tracememsize = val;
6272 break;
6273
6274 case DTRACEACT_SYM:
6275 case DTRACEACT_MOD:
6276 if (!dtrace_priv_kernel(state))
6277 continue;
6278 break;
6279
6280 case DTRACEACT_USYM:
6281 case DTRACEACT_UMOD:
6282 case DTRACEACT_UADDR: {
6283 struct pid *pid = curthread->t_procp->p_pidp;
6284
6285 if (!dtrace_priv_proc(state, &mstate))
6286 continue;
6287
6288 DTRACE_STORE(uint64_t, tomax,
6289 valoffs, (uint64_t)pid->pid_id);
6290 DTRACE_STORE(uint64_t, tomax,
6291 valoffs + sizeof (uint64_t), val);
6292
6293 continue;
6294 }
6295
6296 case DTRACEACT_EXIT: {
6297 /*
6298 * For the exit action, we are going to attempt
6299 * to atomically set our activity to be
6300 * draining. If this fails (either because
6301 * another CPU has beat us to the exit action,
6302 * or because our current activity is something
6303 * other than ACTIVE or WARMUP), we will
6304 * continue. This assures that the exit action
6305 * can be successfully recorded at most once
6306 * when we're in the ACTIVE state. If we're
6307 * encountering the exit() action while in
6308 * COOLDOWN, however, we want to honor the new
6309 * status code. (We know that we're the only
6310 * thread in COOLDOWN, so there is no race.)
6311 */
6312 void *activity = &state->dts_activity;
6313 dtrace_activity_t current = state->dts_activity;
6314
6315 if (current == DTRACE_ACTIVITY_COOLDOWN)
6316 break;
6317
6318 if (current != DTRACE_ACTIVITY_WARMUP)
6319 current = DTRACE_ACTIVITY_ACTIVE;
6320
6321 if (dtrace_cas32(activity, current,
6322 DTRACE_ACTIVITY_DRAINING) != current) {
6323 *flags |= CPU_DTRACE_DROP;
6324 continue;
6325 }
6326
6327 break;
6328 }
6329
6330 default:
6331 ASSERT(0);
6332 }
6333
6334 if (dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF) {
6335 uintptr_t end = valoffs + size;
6336
6337 if (tracememsize != 0 &&
6338 valoffs + tracememsize < end) {
6339 end = valoffs + tracememsize;
6340 tracememsize = 0;
6341 }
6342
6343 if (!dtrace_vcanload((void *)(uintptr_t)val,
6344 &dp->dtdo_rtype, &mstate, vstate))
6345 continue;
6346
6347 /*
6348 * If this is a string, we're going to only
6349 * load until we find the zero byte -- after
6350 * which we'll store zero bytes.
6351 */
6352 if (dp->dtdo_rtype.dtdt_kind ==
6353 DIF_TYPE_STRING) {
6354 char c = '\0' + 1;
6355 int intuple = act->dta_intuple;
6356 size_t s;
6357
6358 for (s = 0; s < size; s++) {
6359 if (c != '\0')
6360 c = dtrace_load8(val++);
6361
6362 DTRACE_STORE(uint8_t, tomax,
6363 valoffs++, c);
6364
6365 if (c == '\0' && intuple)
6366 break;
6367 }
6368
6369 continue;
6370 }
6371
6372 while (valoffs < end) {
6373 DTRACE_STORE(uint8_t, tomax, valoffs++,
6374 dtrace_load8(val++));
6375 }
6376
6377 continue;
6378 }
6379
6380 switch (size) {
6381 case 0:
6382 break;
6383
6384 case sizeof (uint8_t):
6385 DTRACE_STORE(uint8_t, tomax, valoffs, val);
6386 break;
6387 case sizeof (uint16_t):
6388 DTRACE_STORE(uint16_t, tomax, valoffs, val);
6389 break;
6390 case sizeof (uint32_t):
6391 DTRACE_STORE(uint32_t, tomax, valoffs, val);
6392 break;
6393 case sizeof (uint64_t):
6394 DTRACE_STORE(uint64_t, tomax, valoffs, val);
6395 break;
6396 default:
6397 /*
6398 * Any other size should have been returned by
6399 * reference, not by value.
6400 */
6401 ASSERT(0);
6402 break;
6403 }
6404 }
6405
6406 if (*flags & CPU_DTRACE_DROP)
6407 continue;
6408
6409 if (*flags & CPU_DTRACE_FAULT) {
6410 int ndx;
6411 dtrace_action_t *err;
6412
6413 buf->dtb_errors++;
6414
6415 if (probe->dtpr_id == dtrace_probeid_error) {
6416 /*
6417 * There's nothing we can do -- we had an
6418 * error on the error probe. We bump an
6419 * error counter to at least indicate that
6420 * this condition happened.
6421 */
6422 dtrace_error(&state->dts_dblerrors);
6423 continue;
6424 }
6425
6426 if (vtime) {
6427 /*
6428 * Before recursing on dtrace_probe(), we
6429 * need to explicitly clear out our start
6430 * time to prevent it from being accumulated
6431 * into t_dtrace_vtime.
6432 */
6433 curthread->t_dtrace_start = 0;
6434 }
6435
6436 /*
6437 * Iterate over the actions to figure out which action
6438 * we were processing when we experienced the error.
6439 * Note that act points _past_ the faulting action; if
6440 * act is ecb->dte_action, the fault was in the
6441 * predicate, if it's ecb->dte_action->dta_next it's
6442 * in action #1, and so on.
6443 */
6444 for (err = ecb->dte_action, ndx = 0;
6445 err != act; err = err->dta_next, ndx++)
6446 continue;
6447
6448 dtrace_probe_error(state, ecb->dte_epid, ndx,
6449 (mstate.dtms_present & DTRACE_MSTATE_FLTOFFS) ?
6450 mstate.dtms_fltoffs : -1, DTRACE_FLAGS2FLT(*flags),
6451 cpu_core[cpuid].cpuc_dtrace_illval);
6452
6453 continue;
6454 }
6455
6456 if (!committed)
6457 buf->dtb_offset = offs + ecb->dte_size;
6458 }
6459
6460 end = dtrace_gethrtime();
6461 if (vtime)
6462 curthread->t_dtrace_start = end;
6463
6464 CPU->cpu_dtrace_nsec += end - now;
6465
6466 dtrace_interrupt_enable(cookie);
6467 }
6468
6469 /*
6470 * DTrace Probe Hashing Functions
6471 *
6472 * The functions in this section (and indeed, the functions in remaining
6473 * sections) are not _called_ from probe context. (Any exceptions to this are
6474 * marked with a "Note:".) Rather, they are called from elsewhere in the
6475 * DTrace framework to look-up probes in, add probes to and remove probes from
6476 * the DTrace probe hashes. (Each probe is hashed by each element of the
6477 * probe tuple -- allowing for fast lookups, regardless of what was
6478 * specified.)
6479 */
6480 static uint_t
6481 dtrace_hash_str(char *p)
6482 {
6483 unsigned int g;
6484 uint_t hval = 0;
6485
6486 while (*p) {
6487 hval = (hval << 4) + *p++;
6488 if ((g = (hval & 0xf0000000)) != 0)
6489 hval ^= g >> 24;
6490 hval &= ~g;
6491 }
6492 return (hval);
6493 }
6494
6495 static dtrace_hash_t *
6496 dtrace_hash_create(uintptr_t stroffs, uintptr_t nextoffs, uintptr_t prevoffs)
6497 {
6498 dtrace_hash_t *hash = kmem_zalloc(sizeof (dtrace_hash_t), KM_SLEEP);
6499
6500 hash->dth_stroffs = stroffs;
6501 hash->dth_nextoffs = nextoffs;
6502 hash->dth_prevoffs = prevoffs;
6503
6504 hash->dth_size = 1;
6505 hash->dth_mask = hash->dth_size - 1;
6506
6507 hash->dth_tab = kmem_zalloc(hash->dth_size *
6508 sizeof (dtrace_hashbucket_t *), KM_SLEEP);
6509
6510 return (hash);
6511 }
6512
6513 static void
6514 dtrace_hash_destroy(dtrace_hash_t *hash)
6515 {
6516 #ifdef DEBUG
6517 int i;
6518
6519 for (i = 0; i < hash->dth_size; i++)
6520 ASSERT(hash->dth_tab[i] == NULL);
6521 #endif
6522
6523 kmem_free(hash->dth_tab,
6524 hash->dth_size * sizeof (dtrace_hashbucket_t *));
6525 kmem_free(hash, sizeof (dtrace_hash_t));
6526 }
6527
6528 static void
6529 dtrace_hash_resize(dtrace_hash_t *hash)
6530 {
6531 int size = hash->dth_size, i, ndx;
6532 int new_size = hash->dth_size << 1;
6533 int new_mask = new_size - 1;
6534 dtrace_hashbucket_t **new_tab, *bucket, *next;
6535
6536 ASSERT((new_size & new_mask) == 0);
6537
6538 new_tab = kmem_zalloc(new_size * sizeof (void *), KM_SLEEP);
6539
6540 for (i = 0; i < size; i++) {
6541 for (bucket = hash->dth_tab[i]; bucket != NULL; bucket = next) {
6542 dtrace_probe_t *probe = bucket->dthb_chain;
6543
6544 ASSERT(probe != NULL);
6545 ndx = DTRACE_HASHSTR(hash, probe) & new_mask;
6546
6547 next = bucket->dthb_next;
6548 bucket->dthb_next = new_tab[ndx];
6549 new_tab[ndx] = bucket;
6550 }
6551 }
6552
6553 kmem_free(hash->dth_tab, hash->dth_size * sizeof (void *));
6554 hash->dth_tab = new_tab;
6555 hash->dth_size = new_size;
6556 hash->dth_mask = new_mask;
6557 }
6558
6559 static void
6560 dtrace_hash_add(dtrace_hash_t *hash, dtrace_probe_t *new)
6561 {
6562 int hashval = DTRACE_HASHSTR(hash, new);
6563 int ndx = hashval & hash->dth_mask;
6564 dtrace_hashbucket_t *bucket = hash->dth_tab[ndx];
6565 dtrace_probe_t **nextp, **prevp;
6566
6567 for (; bucket != NULL; bucket = bucket->dthb_next) {
6568 if (DTRACE_HASHEQ(hash, bucket->dthb_chain, new))
6569 goto add;
6570 }
6571
6572 if ((hash->dth_nbuckets >> 1) > hash->dth_size) {
6573 dtrace_hash_resize(hash);
6574 dtrace_hash_add(hash, new);
6575 return;
6576 }
6577
6578 bucket = kmem_zalloc(sizeof (dtrace_hashbucket_t), KM_SLEEP);
6579 bucket->dthb_next = hash->dth_tab[ndx];
6580 hash->dth_tab[ndx] = bucket;
6581 hash->dth_nbuckets++;
6582
6583 add:
6584 nextp = DTRACE_HASHNEXT(hash, new);
6585 ASSERT(*nextp == NULL && *(DTRACE_HASHPREV(hash, new)) == NULL);
6586 *nextp = bucket->dthb_chain;
6587
6588 if (bucket->dthb_chain != NULL) {
6589 prevp = DTRACE_HASHPREV(hash, bucket->dthb_chain);
6590 ASSERT(*prevp == NULL);
6591 *prevp = new;
6592 }
6593
6594 bucket->dthb_chain = new;
6595 bucket->dthb_len++;
6596 }
6597
6598 static dtrace_probe_t *
6599 dtrace_hash_lookup(dtrace_hash_t *hash, dtrace_probe_t *template)
6600 {
6601 int hashval = DTRACE_HASHSTR(hash, template);
6602 int ndx = hashval & hash->dth_mask;
6603 dtrace_hashbucket_t *bucket = hash->dth_tab[ndx];
6604
6605 for (; bucket != NULL; bucket = bucket->dthb_next) {
6606 if (DTRACE_HASHEQ(hash, bucket->dthb_chain, template))
6607 return (bucket->dthb_chain);
6608 }
6609
6610 return (NULL);
6611 }
6612
6613 static int
6614 dtrace_hash_collisions(dtrace_hash_t *hash, dtrace_probe_t *template)
6615 {
6616 int hashval = DTRACE_HASHSTR(hash, template);
6617 int ndx = hashval & hash->dth_mask;
6618 dtrace_hashbucket_t *bucket = hash->dth_tab[ndx];
6619
6620 for (; bucket != NULL; bucket = bucket->dthb_next) {
6621 if (DTRACE_HASHEQ(hash, bucket->dthb_chain, template))
6622 return (bucket->dthb_len);
6623 }
6624
6625 return (NULL);
6626 }
6627
6628 static void
6629 dtrace_hash_remove(dtrace_hash_t *hash, dtrace_probe_t *probe)
6630 {
6631 int ndx = DTRACE_HASHSTR(hash, probe) & hash->dth_mask;
6632 dtrace_hashbucket_t *bucket = hash->dth_tab[ndx];
6633
6634 dtrace_probe_t **prevp = DTRACE_HASHPREV(hash, probe);
6635 dtrace_probe_t **nextp = DTRACE_HASHNEXT(hash, probe);
6636
6637 /*
6638 * Find the bucket that we're removing this probe from.
6639 */
6640 for (; bucket != NULL; bucket = bucket->dthb_next) {
6641 if (DTRACE_HASHEQ(hash, bucket->dthb_chain, probe))
6642 break;
6643 }
6644
6645 ASSERT(bucket != NULL);
6646
6647 if (*prevp == NULL) {
6648 if (*nextp == NULL) {
6649 /*
6650 * The removed probe was the only probe on this
6651 * bucket; we need to remove the bucket.
6652 */
6653 dtrace_hashbucket_t *b = hash->dth_tab[ndx];
6654
6655 ASSERT(bucket->dthb_chain == probe);
6656 ASSERT(b != NULL);
6657
6658 if (b == bucket) {
6659 hash->dth_tab[ndx] = bucket->dthb_next;
6660 } else {
6661 while (b->dthb_next != bucket)
6662 b = b->dthb_next;
6663 b->dthb_next = bucket->dthb_next;
6664 }
6665
6666 ASSERT(hash->dth_nbuckets > 0);
6667 hash->dth_nbuckets--;
6668 kmem_free(bucket, sizeof (dtrace_hashbucket_t));
6669 return;
6670 }
6671
6672 bucket->dthb_chain = *nextp;
6673 } else {
6674 *(DTRACE_HASHNEXT(hash, *prevp)) = *nextp;
6675 }
6676
6677 if (*nextp != NULL)
6678 *(DTRACE_HASHPREV(hash, *nextp)) = *prevp;
6679 }
6680
6681 /*
6682 * DTrace Utility Functions
6683 *
6684 * These are random utility functions that are _not_ called from probe context.
6685 */
6686 static int
6687 dtrace_badattr(const dtrace_attribute_t *a)
6688 {
6689 return (a->dtat_name > DTRACE_STABILITY_MAX ||
6690 a->dtat_data > DTRACE_STABILITY_MAX ||
6691 a->dtat_class > DTRACE_CLASS_MAX);
6692 }
6693
6694 /*
6695 * Return a duplicate copy of a string. If the specified string is NULL,
6696 * this function returns a zero-length string.
6697 */
6698 static char *
6699 dtrace_strdup(const char *str)
6700 {
6701 char *new = kmem_zalloc((str != NULL ? strlen(str) : 0) + 1, KM_SLEEP);
6702
6703 if (str != NULL)
6704 (void) strcpy(new, str);
6705
6706 return (new);
6707 }
6708
6709 #define DTRACE_ISALPHA(c) \
6710 (((c) >= 'a' && (c) <= 'z') || ((c) >= 'A' && (c) <= 'Z'))
6711
6712 static int
6713 dtrace_badname(const char *s)
6714 {
6715 char c;
6716
6717 if (s == NULL || (c = *s++) == '\0')
6718 return (0);
6719
6720 if (!DTRACE_ISALPHA(c) && c != '-' && c != '_' && c != '.')
6721 return (1);
6722
6723 while ((c = *s++) != '\0') {
6724 if (!DTRACE_ISALPHA(c) && (c < '0' || c > '9') &&
6725 c != '-' && c != '_' && c != '.' && c != '`')
6726 return (1);
6727 }
6728
6729 return (0);
6730 }
6731
6732 static void
6733 dtrace_cred2priv(cred_t *cr, uint32_t *privp, uid_t *uidp, zoneid_t *zoneidp)
6734 {
6735 uint32_t priv;
6736
6737 if (cr == NULL || PRIV_POLICY_ONLY(cr, PRIV_ALL, B_FALSE)) {
6738 /*
6739 * For DTRACE_PRIV_ALL, the uid and zoneid don't matter.
6740 */
6741 priv = DTRACE_PRIV_ALL;
6742 } else {
6743 *uidp = crgetuid(cr);
6744 *zoneidp = crgetzoneid(cr);
6745
6746 priv = 0;
6747 if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_KERNEL, B_FALSE))
6748 priv |= DTRACE_PRIV_KERNEL | DTRACE_PRIV_USER;
6749 else if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_USER, B_FALSE))
6750 priv |= DTRACE_PRIV_USER;
6751 if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_PROC, B_FALSE))
6752 priv |= DTRACE_PRIV_PROC;
6753 if (PRIV_POLICY_ONLY(cr, PRIV_PROC_OWNER, B_FALSE))
6754 priv |= DTRACE_PRIV_OWNER;
6755 if (PRIV_POLICY_ONLY(cr, PRIV_PROC_ZONE, B_FALSE))
6756 priv |= DTRACE_PRIV_ZONEOWNER;
6757 }
6758
6759 *privp = priv;
6760 }
6761
6762 #ifdef DTRACE_ERRDEBUG
6763 static void
6764 dtrace_errdebug(const char *str)
6765 {
6766 int hval = dtrace_hash_str((char *)str) % DTRACE_ERRHASHSZ;
6767 int occupied = 0;
6768
6769 mutex_enter(&dtrace_errlock);
6770 dtrace_errlast = str;
6771 dtrace_errthread = curthread;
6772
6773 while (occupied++ < DTRACE_ERRHASHSZ) {
6774 if (dtrace_errhash[hval].dter_msg == str) {
6775 dtrace_errhash[hval].dter_count++;
6776 goto out;
6777 }
6778
6779 if (dtrace_errhash[hval].dter_msg != NULL) {
6780 hval = (hval + 1) % DTRACE_ERRHASHSZ;
6781 continue;
6782 }
6783
6784 dtrace_errhash[hval].dter_msg = str;
6785 dtrace_errhash[hval].dter_count = 1;
6786 goto out;
6787 }
6788
6789 panic("dtrace: undersized error hash");
6790 out:
6791 mutex_exit(&dtrace_errlock);
6792 }
6793 #endif
6794
6795 /*
6796 * DTrace Matching Functions
6797 *
6798 * These functions are used to match groups of probes, given some elements of
6799 * a probe tuple, or some globbed expressions for elements of a probe tuple.
6800 */
6801 static int
6802 dtrace_match_priv(const dtrace_probe_t *prp, uint32_t priv, uid_t uid,
6803 zoneid_t zoneid)
6804 {
6805 if (priv != DTRACE_PRIV_ALL) {
6806 uint32_t ppriv = prp->dtpr_provider->dtpv_priv.dtpp_flags;
6807 uint32_t match = priv & ppriv;
6808
6809 /*
6810 * No PRIV_DTRACE_* privileges...
6811 */
6812 if ((priv & (DTRACE_PRIV_PROC | DTRACE_PRIV_USER |
6813 DTRACE_PRIV_KERNEL)) == 0)
6814 return (0);
6815
6816 /*
6817 * No matching bits, but there were bits to match...
6818 */
6819 if (match == 0 && ppriv != 0)
6820 return (0);
6821
6822 /*
6823 * Need to have permissions to the process, but don't...
6824 */
6825 if (((ppriv & ~match) & DTRACE_PRIV_OWNER) != 0 &&
6826 uid != prp->dtpr_provider->dtpv_priv.dtpp_uid) {
6827 return (0);
6828 }
6829
6830 /*
6831 * Need to be in the same zone unless we possess the
6832 * privilege to examine all zones.
6833 */
6834 if (((ppriv & ~match) & DTRACE_PRIV_ZONEOWNER) != 0 &&
6835 zoneid != prp->dtpr_provider->dtpv_priv.dtpp_zoneid) {
6836 return (0);
6837 }
6838 }
6839
6840 return (1);
6841 }
6842
6843 /*
6844 * dtrace_match_probe compares a dtrace_probe_t to a pre-compiled key, which
6845 * consists of input pattern strings and an ops-vector to evaluate them.
6846 * This function returns >0 for match, 0 for no match, and <0 for error.
6847 */
6848 static int
6849 dtrace_match_probe(const dtrace_probe_t *prp, const dtrace_probekey_t *pkp,
6850 uint32_t priv, uid_t uid, zoneid_t zoneid)
6851 {
6852 dtrace_provider_t *pvp = prp->dtpr_provider;
6853 int rv;
6854
6855 if (pvp->dtpv_defunct)
6856 return (0);
6857
6858 if ((rv = pkp->dtpk_pmatch(pvp->dtpv_name, pkp->dtpk_prov, 0)) <= 0)
6859 return (rv);
6860
6861 if ((rv = pkp->dtpk_mmatch(prp->dtpr_mod, pkp->dtpk_mod, 0)) <= 0)
6862 return (rv);
6863
6864 if ((rv = pkp->dtpk_fmatch(prp->dtpr_func, pkp->dtpk_func, 0)) <= 0)
6865 return (rv);
6866
6867 if ((rv = pkp->dtpk_nmatch(prp->dtpr_name, pkp->dtpk_name, 0)) <= 0)
6868 return (rv);
6869
6870 if (dtrace_match_priv(prp, priv, uid, zoneid) == 0)
6871 return (0);
6872
6873 return (rv);
6874 }
6875
6876 /*
6877 * dtrace_match_glob() is a safe kernel implementation of the gmatch(3GEN)
6878 * interface for matching a glob pattern 'p' to an input string 's'. Unlike
6879 * libc's version, the kernel version only applies to 8-bit ASCII strings.
6880 * In addition, all of the recursion cases except for '*' matching have been
6881 * unwound. For '*', we still implement recursive evaluation, but a depth
6882 * counter is maintained and matching is aborted if we recurse too deep.
6883 * The function returns 0 if no match, >0 if match, and <0 if recursion error.
6884 */
6885 static int
6886 dtrace_match_glob(const char *s, const char *p, int depth)
6887 {
6888 const char *olds;
6889 char s1, c;
6890 int gs;
6891
6892 if (depth > DTRACE_PROBEKEY_MAXDEPTH)
6893 return (-1);
6894
6895 if (s == NULL)
6896 s = ""; /* treat NULL as empty string */
6897
6898 top:
6899 olds = s;
6900 s1 = *s++;
6901
6902 if (p == NULL)
6903 return (0);
6904
6905 if ((c = *p++) == '\0')
6906 return (s1 == '\0');
6907
6908 switch (c) {
6909 case '[': {
6910 int ok = 0, notflag = 0;
6911 char lc = '\0';
6912
6913 if (s1 == '\0')
6914 return (0);
6915
6916 if (*p == '!') {
6917 notflag = 1;
6918 p++;
6919 }
6920
6921 if ((c = *p++) == '\0')
6922 return (0);
6923
6924 do {
6925 if (c == '-' && lc != '\0' && *p != ']') {
6926 if ((c = *p++) == '\0')
6927 return (0);
6928 if (c == '\\' && (c = *p++) == '\0')
6929 return (0);
6930
6931 if (notflag) {
6932 if (s1 < lc || s1 > c)
6933 ok++;
6934 else
6935 return (0);
6936 } else if (lc <= s1 && s1 <= c)
6937 ok++;
6938
6939 } else if (c == '\\' && (c = *p++) == '\0')
6940 return (0);
6941
6942 lc = c; /* save left-hand 'c' for next iteration */
6943
6944 if (notflag) {
6945 if (s1 != c)
6946 ok++;
6947 else
6948 return (0);
6949 } else if (s1 == c)
6950 ok++;
6951
6952 if ((c = *p++) == '\0')
6953 return (0);
6954
6955 } while (c != ']');
6956
6957 if (ok)
6958 goto top;
6959
6960 return (0);
6961 }
6962
6963 case '\\':
6964 if ((c = *p++) == '\0')
6965 return (0);
6966 /*FALLTHRU*/
6967
6968 default:
6969 if (c != s1)
6970 return (0);
6971 /*FALLTHRU*/
6972
6973 case '?':
6974 if (s1 != '\0')
6975 goto top;
6976 return (0);
6977
6978 case '*':
6979 while (*p == '*')
6980 p++; /* consecutive *'s are identical to a single one */
6981
6982 if (*p == '\0')
6983 return (1);
6984
6985 for (s = olds; *s != '\0'; s++) {
6986 if ((gs = dtrace_match_glob(s, p, depth + 1)) != 0)
6987 return (gs);
6988 }
6989
6990 return (0);
6991 }
6992 }
6993
6994 /*ARGSUSED*/
6995 static int
6996 dtrace_match_string(const char *s, const char *p, int depth)
6997 {
6998 return (s != NULL && strcmp(s, p) == 0);
6999 }
7000
7001 /*ARGSUSED*/
7002 static int
7003 dtrace_match_nul(const char *s, const char *p, int depth)
7004 {
7005 return (1); /* always match the empty pattern */
7006 }
7007
7008 /*ARGSUSED*/
7009 static int
7010 dtrace_match_nonzero(const char *s, const char *p, int depth)
7011 {
7012 return (s != NULL && s[0] != '\0');
7013 }
7014
7015 static int
7016 dtrace_match(const dtrace_probekey_t *pkp, uint32_t priv, uid_t uid,
7017 zoneid_t zoneid, int (*matched)(dtrace_probe_t *, void *), void *arg)
7018 {
7019 dtrace_probe_t template, *probe;
7020 dtrace_hash_t *hash = NULL;
7021 int len, rc, best = INT_MAX, nmatched = 0;
7022 dtrace_id_t i;
7023
7024 ASSERT(MUTEX_HELD(&dtrace_lock));
7025
7026 /*
7027 * If the probe ID is specified in the key, just lookup by ID and
7028 * invoke the match callback once if a matching probe is found.
7029 */
7030 if (pkp->dtpk_id != DTRACE_IDNONE) {
7031 if ((probe = dtrace_probe_lookup_id(pkp->dtpk_id)) != NULL &&
7032 dtrace_match_probe(probe, pkp, priv, uid, zoneid) > 0) {
7033 if ((*matched)(probe, arg) == DTRACE_MATCH_FAIL)
7034 return (DTRACE_MATCH_FAIL);
7035 nmatched++;
7036 }
7037 return (nmatched);
7038 }
7039
7040 template.dtpr_mod = (char *)pkp->dtpk_mod;
7041 template.dtpr_func = (char *)pkp->dtpk_func;
7042 template.dtpr_name = (char *)pkp->dtpk_name;
7043
7044 /*
7045 * We want to find the most distinct of the module name, function
7046 * name, and name. So for each one that is not a glob pattern or
7047 * empty string, we perform a lookup in the corresponding hash and
7048 * use the hash table with the fewest collisions to do our search.
7049 */
7050 if (pkp->dtpk_mmatch == &dtrace_match_string &&
7051 (len = dtrace_hash_collisions(dtrace_bymod, &template)) < best) {
7052 best = len;
7053 hash = dtrace_bymod;
7054 }
7055
7056 if (pkp->dtpk_fmatch == &dtrace_match_string &&
7057 (len = dtrace_hash_collisions(dtrace_byfunc, &template)) < best) {
7058 best = len;
7059 hash = dtrace_byfunc;
7060 }
7061
7062 if (pkp->dtpk_nmatch == &dtrace_match_string &&
7063 (len = dtrace_hash_collisions(dtrace_byname, &template)) < best) {
7064 best = len;
7065 hash = dtrace_byname;
7066 }
7067
7068 /*
7069 * If we did not select a hash table, iterate over every probe and
7070 * invoke our callback for each one that matches our input probe key.
7071 */
7072 if (hash == NULL) {
7073 for (i = 0; i < dtrace_nprobes; i++) {
7074 if ((probe = dtrace_probes[i]) == NULL ||
7075 dtrace_match_probe(probe, pkp, priv, uid,
7076 zoneid) <= 0)
7077 continue;
7078
7079 nmatched++;
7080
7081 if ((rc = (*matched)(probe, arg)) !=
7082 DTRACE_MATCH_NEXT) {
7083 if (rc == DTRACE_MATCH_FAIL)
7084 return (DTRACE_MATCH_FAIL);
7085 break;
7086 }
7087 }
7088
7089 return (nmatched);
7090 }
7091
7092 /*
7093 * If we selected a hash table, iterate over each probe of the same key
7094 * name and invoke the callback for every probe that matches the other
7095 * attributes of our input probe key.
7096 */
7097 for (probe = dtrace_hash_lookup(hash, &template); probe != NULL;
7098 probe = *(DTRACE_HASHNEXT(hash, probe))) {
7099
7100 if (dtrace_match_probe(probe, pkp, priv, uid, zoneid) <= 0)
7101 continue;
7102
7103 nmatched++;
7104
7105 if ((rc = (*matched)(probe, arg)) != DTRACE_MATCH_NEXT) {
7106 if (rc == DTRACE_MATCH_FAIL)
7107 return (DTRACE_MATCH_FAIL);
7108 break;
7109 }
7110 }
7111
7112 return (nmatched);
7113 }
7114
7115 /*
7116 * Return the function pointer dtrace_probecmp() should use to compare the
7117 * specified pattern with a string. For NULL or empty patterns, we select
7118 * dtrace_match_nul(). For glob pattern strings, we use dtrace_match_glob().
7119 * For non-empty non-glob strings, we use dtrace_match_string().
7120 */
7121 static dtrace_probekey_f *
7122 dtrace_probekey_func(const char *p)
7123 {
7124 char c;
7125
7126 if (p == NULL || *p == '\0')
7127 return (&dtrace_match_nul);
7128
7129 while ((c = *p++) != '\0') {
7130 if (c == '[' || c == '?' || c == '*' || c == '\\')
7131 return (&dtrace_match_glob);
7132 }
7133
7134 return (&dtrace_match_string);
7135 }
7136
7137 /*
7138 * Build a probe comparison key for use with dtrace_match_probe() from the
7139 * given probe description. By convention, a null key only matches anchored
7140 * probes: if each field is the empty string, reset dtpk_fmatch to
7141 * dtrace_match_nonzero().
7142 */
7143 static void
7144 dtrace_probekey(const dtrace_probedesc_t *pdp, dtrace_probekey_t *pkp)
7145 {
7146 pkp->dtpk_prov = pdp->dtpd_provider;
7147 pkp->dtpk_pmatch = dtrace_probekey_func(pdp->dtpd_provider);
7148
7149 pkp->dtpk_mod = pdp->dtpd_mod;
7150 pkp->dtpk_mmatch = dtrace_probekey_func(pdp->dtpd_mod);
7151
7152 pkp->dtpk_func = pdp->dtpd_func;
7153 pkp->dtpk_fmatch = dtrace_probekey_func(pdp->dtpd_func);
7154
7155 pkp->dtpk_name = pdp->dtpd_name;
7156 pkp->dtpk_nmatch = dtrace_probekey_func(pdp->dtpd_name);
7157
7158 pkp->dtpk_id = pdp->dtpd_id;
7159
7160 if (pkp->dtpk_id == DTRACE_IDNONE &&
7161 pkp->dtpk_pmatch == &dtrace_match_nul &&
7162 pkp->dtpk_mmatch == &dtrace_match_nul &&
7163 pkp->dtpk_fmatch == &dtrace_match_nul &&
7164 pkp->dtpk_nmatch == &dtrace_match_nul)
7165 pkp->dtpk_fmatch = &dtrace_match_nonzero;
7166 }
7167
7168 /*
7169 * DTrace Provider-to-Framework API Functions
7170 *
7171 * These functions implement much of the Provider-to-Framework API, as
7172 * described in <sys/dtrace.h>. The parts of the API not in this section are
7173 * the functions in the API for probe management (found below), and
7174 * dtrace_probe() itself (found above).
7175 */
7176
7177 /*
7178 * Register the calling provider with the DTrace framework. This should
7179 * generally be called by DTrace providers in their attach(9E) entry point.
7180 */
7181 int
7182 dtrace_register(const char *name, const dtrace_pattr_t *pap, uint32_t priv,
7183 cred_t *cr, const dtrace_pops_t *pops, void *arg, dtrace_provider_id_t *idp)
7184 {
7185 dtrace_provider_t *provider;
7186
7187 if (name == NULL || pap == NULL || pops == NULL || idp == NULL) {
7188 cmn_err(CE_WARN, "failed to register provider '%s': invalid "
7189 "arguments", name ? name : "<NULL>");
7190 return (EINVAL);
7191 }
7192
7193 if (name[0] == '\0' || dtrace_badname(name)) {
7194 cmn_err(CE_WARN, "failed to register provider '%s': invalid "
7195 "provider name", name);
7196 return (EINVAL);
7197 }
7198
7199 if ((pops->dtps_provide == NULL && pops->dtps_provide_module == NULL) ||
7200 pops->dtps_enable == NULL || pops->dtps_disable == NULL ||
7201 pops->dtps_destroy == NULL ||
7202 ((pops->dtps_resume == NULL) != (pops->dtps_suspend == NULL))) {
7203 cmn_err(CE_WARN, "failed to register provider '%s': invalid "
7204 "provider ops", name);
7205 return (EINVAL);
7206 }
7207
7208 if (dtrace_badattr(&pap->dtpa_provider) ||
7209 dtrace_badattr(&pap->dtpa_mod) ||
7210 dtrace_badattr(&pap->dtpa_func) ||
7211 dtrace_badattr(&pap->dtpa_name) ||
7212 dtrace_badattr(&pap->dtpa_args)) {
7213 cmn_err(CE_WARN, "failed to register provider '%s': invalid "
7214 "provider attributes", name);
7215 return (EINVAL);
7216 }
7217
7218 if (priv & ~DTRACE_PRIV_ALL) {
7219 cmn_err(CE_WARN, "failed to register provider '%s': invalid "
7220 "privilege attributes", name);
7221 return (EINVAL);
7222 }
7223
7224 if ((priv & DTRACE_PRIV_KERNEL) &&
7225 (priv & (DTRACE_PRIV_USER | DTRACE_PRIV_OWNER)) &&
7226 pops->dtps_mode == NULL) {
7227 cmn_err(CE_WARN, "failed to register provider '%s': need "
7228 "dtps_mode() op for given privilege attributes", name);
7229 return (EINVAL);
7230 }
7231
7232 provider = kmem_zalloc(sizeof (dtrace_provider_t), KM_SLEEP);
7233 provider->dtpv_name = kmem_alloc(strlen(name) + 1, KM_SLEEP);
7234 (void) strcpy(provider->dtpv_name, name);
7235
7236 provider->dtpv_attr = *pap;
7237 provider->dtpv_priv.dtpp_flags = priv;
7238 if (cr != NULL) {
7239 provider->dtpv_priv.dtpp_uid = crgetuid(cr);
7240 provider->dtpv_priv.dtpp_zoneid = crgetzoneid(cr);
7241 }
7242 provider->dtpv_pops = *pops;
7243
7244 if (pops->dtps_provide == NULL) {
7245 ASSERT(pops->dtps_provide_module != NULL);
7246 provider->dtpv_pops.dtps_provide =
7247 (void (*)(void *, const dtrace_probedesc_t *))dtrace_nullop;
7248 }
7249
7250 if (pops->dtps_provide_module == NULL) {
7251 ASSERT(pops->dtps_provide != NULL);
7252 provider->dtpv_pops.dtps_provide_module =
7253 (void (*)(void *, struct modctl *))dtrace_nullop;
7254 }
7255
7256 if (pops->dtps_suspend == NULL) {
7257 ASSERT(pops->dtps_resume == NULL);
7258 provider->dtpv_pops.dtps_suspend =
7259 (void (*)(void *, dtrace_id_t, void *))dtrace_nullop;
7260 provider->dtpv_pops.dtps_resume =
7261 (void (*)(void *, dtrace_id_t, void *))dtrace_nullop;
7262 }
7263
7264 provider->dtpv_arg = arg;
7265 *idp = (dtrace_provider_id_t)provider;
7266
7267 if (pops == &dtrace_provider_ops) {
7268 ASSERT(MUTEX_HELD(&dtrace_provider_lock));
7269 ASSERT(MUTEX_HELD(&dtrace_lock));
7270 ASSERT(dtrace_anon.dta_enabling == NULL);
7271
7272 /*
7273 * We make sure that the DTrace provider is at the head of
7274 * the provider chain.
7275 */
7276 provider->dtpv_next = dtrace_provider;
7277 dtrace_provider = provider;
7278 return (0);
7279 }
7280
7281 mutex_enter(&dtrace_provider_lock);
7282 mutex_enter(&dtrace_lock);
7283
7284 /*
7285 * If there is at least one provider registered, we'll add this
7286 * provider after the first provider.
7287 */
7288 if (dtrace_provider != NULL) {
7289 provider->dtpv_next = dtrace_provider->dtpv_next;
7290 dtrace_provider->dtpv_next = provider;
7291 } else {
7292 dtrace_provider = provider;
7293 }
7294
7295 if (dtrace_retained != NULL) {
7296 dtrace_enabling_provide(provider);
7297
7298 /*
7299 * Now we need to call dtrace_enabling_matchall() -- which
7300 * will acquire cpu_lock and dtrace_lock. We therefore need
7301 * to drop all of our locks before calling into it...
7302 */
7303 mutex_exit(&dtrace_lock);
7304 mutex_exit(&dtrace_provider_lock);
7305 dtrace_enabling_matchall();
7306
7307 return (0);
7308 }
7309
7310 mutex_exit(&dtrace_lock);
7311 mutex_exit(&dtrace_provider_lock);
7312
7313 return (0);
7314 }
7315
7316 /*
7317 * Unregister the specified provider from the DTrace framework. This should
7318 * generally be called by DTrace providers in their detach(9E) entry point.
7319 */
7320 int
7321 dtrace_unregister(dtrace_provider_id_t id)
7322 {
7323 dtrace_provider_t *old = (dtrace_provider_t *)id;
7324 dtrace_provider_t *prev = NULL;
7325 int i, self = 0, noreap = 0;
7326 dtrace_probe_t *probe, *first = NULL;
7327
7328 if (old->dtpv_pops.dtps_enable ==
7329 (int (*)(void *, dtrace_id_t, void *))dtrace_enable_nullop) {
7330 /*
7331 * If DTrace itself is the provider, we're called with locks
7332 * already held.
7333 */
7334 ASSERT(old == dtrace_provider);
7335 ASSERT(dtrace_devi != NULL);
7336 ASSERT(MUTEX_HELD(&dtrace_provider_lock));
7337 ASSERT(MUTEX_HELD(&dtrace_lock));
7338 self = 1;
7339
7340 if (dtrace_provider->dtpv_next != NULL) {
7341 /*
7342 * There's another provider here; return failure.
7343 */
7344 return (EBUSY);
7345 }
7346 } else {
7347 mutex_enter(&dtrace_provider_lock);
7348 mutex_enter(&mod_lock);
7349 mutex_enter(&dtrace_lock);
7350 }
7351
7352 /*
7353 * If anyone has /dev/dtrace open, or if there are anonymous enabled
7354 * probes, we refuse to let providers slither away, unless this
7355 * provider has already been explicitly invalidated.
7356 */
7357 if (!old->dtpv_defunct &&
7358 (dtrace_opens || (dtrace_anon.dta_state != NULL &&
7359 dtrace_anon.dta_state->dts_necbs > 0))) {
7360 if (!self) {
7361 mutex_exit(&dtrace_lock);
7362 mutex_exit(&mod_lock);
7363 mutex_exit(&dtrace_provider_lock);
7364 }
7365 return (EBUSY);
7366 }
7367
7368 /*
7369 * Attempt to destroy the probes associated with this provider.
7370 */
7371 for (i = 0; i < dtrace_nprobes; i++) {
7372 if ((probe = dtrace_probes[i]) == NULL)
7373 continue;
7374
7375 if (probe->dtpr_provider != old)
7376 continue;
7377
7378 if (probe->dtpr_ecb == NULL)
7379 continue;
7380
7381 /*
7382 * If we are trying to unregister a defunct provider, and the
7383 * provider was made defunct within the interval dictated by
7384 * dtrace_unregister_defunct_reap, we'll (asynchronously)
7385 * attempt to reap our enablings. To denote that the provider
7386 * should reattempt to unregister itself at some point in the
7387 * future, we will return a differentiable error code (EAGAIN
7388 * instead of EBUSY) in this case.
7389 */
7390 if (dtrace_gethrtime() - old->dtpv_defunct >
7391 dtrace_unregister_defunct_reap)
7392 noreap = 1;
7393
7394 if (!self) {
7395 mutex_exit(&dtrace_lock);
7396 mutex_exit(&mod_lock);
7397 mutex_exit(&dtrace_provider_lock);
7398 }
7399
7400 if (noreap)
7401 return (EBUSY);
7402
7403 (void) taskq_dispatch(dtrace_taskq,
7404 (task_func_t *)dtrace_enabling_reap, NULL, TQ_SLEEP);
7405
7406 return (EAGAIN);
7407 }
7408
7409 /*
7410 * All of the probes for this provider are disabled; we can safely
7411 * remove all of them from their hash chains and from the probe array.
7412 */
7413 for (i = 0; i < dtrace_nprobes; i++) {
7414 if ((probe = dtrace_probes[i]) == NULL)
7415 continue;
7416
7417 if (probe->dtpr_provider != old)
7418 continue;
7419
7420 dtrace_probes[i] = NULL;
7421
7422 dtrace_hash_remove(dtrace_bymod, probe);
7423 dtrace_hash_remove(dtrace_byfunc, probe);
7424 dtrace_hash_remove(dtrace_byname, probe);
7425
7426 if (first == NULL) {
7427 first = probe;
7428 probe->dtpr_nextmod = NULL;
7429 } else {
7430 probe->dtpr_nextmod = first;
7431 first = probe;
7432 }
7433 }
7434
7435 /*
7436 * The provider's probes have been removed from the hash chains and
7437 * from the probe array. Now issue a dtrace_sync() to be sure that
7438 * everyone has cleared out from any probe array processing.
7439 */
7440 dtrace_sync();
7441
7442 for (probe = first; probe != NULL; probe = first) {
7443 first = probe->dtpr_nextmod;
7444
7445 old->dtpv_pops.dtps_destroy(old->dtpv_arg, probe->dtpr_id,
7446 probe->dtpr_arg);
7447 kmem_free(probe->dtpr_mod, strlen(probe->dtpr_mod) + 1);
7448 kmem_free(probe->dtpr_func, strlen(probe->dtpr_func) + 1);
7449 kmem_free(probe->dtpr_name, strlen(probe->dtpr_name) + 1);
7450 vmem_free(dtrace_arena, (void *)(uintptr_t)(probe->dtpr_id), 1);
7451 kmem_free(probe, sizeof (dtrace_probe_t));
7452 }
7453
7454 if ((prev = dtrace_provider) == old) {
7455 ASSERT(self || dtrace_devi == NULL);
7456 ASSERT(old->dtpv_next == NULL || dtrace_devi == NULL);
7457 dtrace_provider = old->dtpv_next;
7458 } else {
7459 while (prev != NULL && prev->dtpv_next != old)
7460 prev = prev->dtpv_next;
7461
7462 if (prev == NULL) {
7463 panic("attempt to unregister non-existent "
7464 "dtrace provider %p\n", (void *)id);
7465 }
7466
7467 prev->dtpv_next = old->dtpv_next;
7468 }
7469
7470 if (!self) {
7471 mutex_exit(&dtrace_lock);
7472 mutex_exit(&mod_lock);
7473 mutex_exit(&dtrace_provider_lock);
7474 }
7475
7476 kmem_free(old->dtpv_name, strlen(old->dtpv_name) + 1);
7477 kmem_free(old, sizeof (dtrace_provider_t));
7478
7479 return (0);
7480 }
7481
7482 /*
7483 * Invalidate the specified provider. All subsequent probe lookups for the
7484 * specified provider will fail, but its probes will not be removed.
7485 */
7486 void
7487 dtrace_invalidate(dtrace_provider_id_t id)
7488 {
7489 dtrace_provider_t *pvp = (dtrace_provider_t *)id;
7490
7491 ASSERT(pvp->dtpv_pops.dtps_enable !=
7492 (int (*)(void *, dtrace_id_t, void *))dtrace_enable_nullop);
7493
7494 mutex_enter(&dtrace_provider_lock);
7495 mutex_enter(&dtrace_lock);
7496
7497 pvp->dtpv_defunct = dtrace_gethrtime();
7498
7499 mutex_exit(&dtrace_lock);
7500 mutex_exit(&dtrace_provider_lock);
7501 }
7502
7503 /*
7504 * Indicate whether or not DTrace has attached.
7505 */
7506 int
7507 dtrace_attached(void)
7508 {
7509 /*
7510 * dtrace_provider will be non-NULL iff the DTrace driver has
7511 * attached. (It's non-NULL because DTrace is always itself a
7512 * provider.)
7513 */
7514 return (dtrace_provider != NULL);
7515 }
7516
7517 /*
7518 * Remove all the unenabled probes for the given provider. This function is
7519 * not unlike dtrace_unregister(), except that it doesn't remove the provider
7520 * -- just as many of its associated probes as it can.
7521 */
7522 int
7523 dtrace_condense(dtrace_provider_id_t id)
7524 {
7525 dtrace_provider_t *prov = (dtrace_provider_t *)id;
7526 int i;
7527 dtrace_probe_t *probe;
7528
7529 /*
7530 * Make sure this isn't the dtrace provider itself.
7531 */
7532 ASSERT(prov->dtpv_pops.dtps_enable !=
7533 (int (*)(void *, dtrace_id_t, void *))dtrace_enable_nullop);
7534
7535 mutex_enter(&dtrace_provider_lock);
7536 mutex_enter(&dtrace_lock);
7537
7538 /*
7539 * Attempt to destroy the probes associated with this provider.
7540 */
7541 for (i = 0; i < dtrace_nprobes; i++) {
7542 if ((probe = dtrace_probes[i]) == NULL)
7543 continue;
7544
7545 if (probe->dtpr_provider != prov)
7546 continue;
7547
7548 if (probe->dtpr_ecb != NULL)
7549 continue;
7550
7551 dtrace_probes[i] = NULL;
7552
7553 dtrace_hash_remove(dtrace_bymod, probe);
7554 dtrace_hash_remove(dtrace_byfunc, probe);
7555 dtrace_hash_remove(dtrace_byname, probe);
7556
7557 prov->dtpv_pops.dtps_destroy(prov->dtpv_arg, i + 1,
7558 probe->dtpr_arg);
7559 kmem_free(probe->dtpr_mod, strlen(probe->dtpr_mod) + 1);
7560 kmem_free(probe->dtpr_func, strlen(probe->dtpr_func) + 1);
7561 kmem_free(probe->dtpr_name, strlen(probe->dtpr_name) + 1);
7562 kmem_free(probe, sizeof (dtrace_probe_t));
7563 vmem_free(dtrace_arena, (void *)((uintptr_t)i + 1), 1);
7564 }
7565
7566 mutex_exit(&dtrace_lock);
7567 mutex_exit(&dtrace_provider_lock);
7568
7569 return (0);
7570 }
7571
7572 /*
7573 * DTrace Probe Management Functions
7574 *
7575 * The functions in this section perform the DTrace probe management,
7576 * including functions to create probes, look-up probes, and call into the
7577 * providers to request that probes be provided. Some of these functions are
7578 * in the Provider-to-Framework API; these functions can be identified by the
7579 * fact that they are not declared "static".
7580 */
7581
7582 /*
7583 * Create a probe with the specified module name, function name, and name.
7584 */
7585 dtrace_id_t
7586 dtrace_probe_create(dtrace_provider_id_t prov, const char *mod,
7587 const char *func, const char *name, int aframes, void *arg)
7588 {
7589 dtrace_probe_t *probe, **probes;
7590 dtrace_provider_t *provider = (dtrace_provider_t *)prov;
7591 dtrace_id_t id;
7592
7593 if (provider == dtrace_provider) {
7594 ASSERT(MUTEX_HELD(&dtrace_lock));
7595 } else {
7596 mutex_enter(&dtrace_lock);
7597 }
7598
7599 id = (dtrace_id_t)(uintptr_t)vmem_alloc(dtrace_arena, 1,
7600 VM_BESTFIT | VM_SLEEP);
7601 probe = kmem_zalloc(sizeof (dtrace_probe_t), KM_SLEEP);
7602
7603 probe->dtpr_id = id;
7604 probe->dtpr_gen = dtrace_probegen++;
7605 probe->dtpr_mod = dtrace_strdup(mod);
7606 probe->dtpr_func = dtrace_strdup(func);
7607 probe->dtpr_name = dtrace_strdup(name);
7608 probe->dtpr_arg = arg;
7609 probe->dtpr_aframes = aframes;
7610 probe->dtpr_provider = provider;
7611
7612 dtrace_hash_add(dtrace_bymod, probe);
7613 dtrace_hash_add(dtrace_byfunc, probe);
7614 dtrace_hash_add(dtrace_byname, probe);
7615
7616 if (id - 1 >= dtrace_nprobes) {
7617 size_t osize = dtrace_nprobes * sizeof (dtrace_probe_t *);
7618 size_t nsize = osize << 1;
7619
7620 if (nsize == 0) {
7621 ASSERT(osize == 0);
7622 ASSERT(dtrace_probes == NULL);
7623 nsize = sizeof (dtrace_probe_t *);
7624 }
7625
7626 probes = kmem_zalloc(nsize, KM_SLEEP);
7627
7628 if (dtrace_probes == NULL) {
7629 ASSERT(osize == 0);
7630 dtrace_probes = probes;
7631 dtrace_nprobes = 1;
7632 } else {
7633 dtrace_probe_t **oprobes = dtrace_probes;
7634
7635 bcopy(oprobes, probes, osize);
7636 dtrace_membar_producer();
7637 dtrace_probes = probes;
7638
7639 dtrace_sync();
7640
7641 /*
7642 * All CPUs are now seeing the new probes array; we can
7643 * safely free the old array.
7644 */
7645 kmem_free(oprobes, osize);
7646 dtrace_nprobes <<= 1;
7647 }
7648
7649 ASSERT(id - 1 < dtrace_nprobes);
7650 }
7651
7652 ASSERT(dtrace_probes[id - 1] == NULL);
7653 dtrace_probes[id - 1] = probe;
7654
7655 if (provider != dtrace_provider)
7656 mutex_exit(&dtrace_lock);
7657
7658 return (id);
7659 }
7660
7661 static dtrace_probe_t *
7662 dtrace_probe_lookup_id(dtrace_id_t id)
7663 {
7664 ASSERT(MUTEX_HELD(&dtrace_lock));
7665
7666 if (id == 0 || id > dtrace_nprobes)
7667 return (NULL);
7668
7669 return (dtrace_probes[id - 1]);
7670 }
7671
7672 static int
7673 dtrace_probe_lookup_match(dtrace_probe_t *probe, void *arg)
7674 {
7675 *((dtrace_id_t *)arg) = probe->dtpr_id;
7676
7677 return (DTRACE_MATCH_DONE);
7678 }
7679
7680 /*
7681 * Look up a probe based on provider and one or more of module name, function
7682 * name and probe name.
7683 */
7684 dtrace_id_t
7685 dtrace_probe_lookup(dtrace_provider_id_t prid, const char *mod,
7686 const char *func, const char *name)
7687 {
7688 dtrace_probekey_t pkey;
7689 dtrace_id_t id;
7690 int match;
7691
7692 pkey.dtpk_prov = ((dtrace_provider_t *)prid)->dtpv_name;
7693 pkey.dtpk_pmatch = &dtrace_match_string;
7694 pkey.dtpk_mod = mod;
7695 pkey.dtpk_mmatch = mod ? &dtrace_match_string : &dtrace_match_nul;
7696 pkey.dtpk_func = func;
7697 pkey.dtpk_fmatch = func ? &dtrace_match_string : &dtrace_match_nul;
7698 pkey.dtpk_name = name;
7699 pkey.dtpk_nmatch = name ? &dtrace_match_string : &dtrace_match_nul;
7700 pkey.dtpk_id = DTRACE_IDNONE;
7701
7702 mutex_enter(&dtrace_lock);
7703 match = dtrace_match(&pkey, DTRACE_PRIV_ALL, 0, 0,
7704 dtrace_probe_lookup_match, &id);
7705 mutex_exit(&dtrace_lock);
7706
7707 ASSERT(match == 1 || match == 0);
7708 return (match ? id : 0);
7709 }
7710
7711 /*
7712 * Returns the probe argument associated with the specified probe.
7713 */
7714 void *
7715 dtrace_probe_arg(dtrace_provider_id_t id, dtrace_id_t pid)
7716 {
7717 dtrace_probe_t *probe;
7718 void *rval = NULL;
7719
7720 mutex_enter(&dtrace_lock);
7721
7722 if ((probe = dtrace_probe_lookup_id(pid)) != NULL &&
7723 probe->dtpr_provider == (dtrace_provider_t *)id)
7724 rval = probe->dtpr_arg;
7725
7726 mutex_exit(&dtrace_lock);
7727
7728 return (rval);
7729 }
7730
7731 /*
7732 * Copy a probe into a probe description.
7733 */
7734 static void
7735 dtrace_probe_description(const dtrace_probe_t *prp, dtrace_probedesc_t *pdp)
7736 {
7737 bzero(pdp, sizeof (dtrace_probedesc_t));
7738 pdp->dtpd_id = prp->dtpr_id;
7739
7740 (void) strncpy(pdp->dtpd_provider,
7741 prp->dtpr_provider->dtpv_name, DTRACE_PROVNAMELEN - 1);
7742
7743 (void) strncpy(pdp->dtpd_mod, prp->dtpr_mod, DTRACE_MODNAMELEN - 1);
7744 (void) strncpy(pdp->dtpd_func, prp->dtpr_func, DTRACE_FUNCNAMELEN - 1);
7745 (void) strncpy(pdp->dtpd_name, prp->dtpr_name, DTRACE_NAMELEN - 1);
7746 }
7747
7748 /*
7749 * Called to indicate that a probe -- or probes -- should be provided by a
7750 * specfied provider. If the specified description is NULL, the provider will
7751 * be told to provide all of its probes. (This is done whenever a new
7752 * consumer comes along, or whenever a retained enabling is to be matched.) If
7753 * the specified description is non-NULL, the provider is given the
7754 * opportunity to dynamically provide the specified probe, allowing providers
7755 * to support the creation of probes on-the-fly. (So-called _autocreated_
7756 * probes.) If the provider is NULL, the operations will be applied to all
7757 * providers; if the provider is non-NULL the operations will only be applied
7758 * to the specified provider. The dtrace_provider_lock must be held, and the
7759 * dtrace_lock must _not_ be held -- the provider's dtps_provide() operation
7760 * will need to grab the dtrace_lock when it reenters the framework through
7761 * dtrace_probe_lookup(), dtrace_probe_create(), etc.
7762 */
7763 static void
7764 dtrace_probe_provide(dtrace_probedesc_t *desc, dtrace_provider_t *prv)
7765 {
7766 struct modctl *ctl;
7767 int all = 0;
7768
7769 ASSERT(MUTEX_HELD(&dtrace_provider_lock));
7770
7771 if (prv == NULL) {
7772 all = 1;
7773 prv = dtrace_provider;
7774 }
7775
7776 do {
7777 /*
7778 * First, call the blanket provide operation.
7779 */
7780 prv->dtpv_pops.dtps_provide(prv->dtpv_arg, desc);
7781
7782 /*
7783 * Now call the per-module provide operation. We will grab
7784 * mod_lock to prevent the list from being modified. Note
7785 * that this also prevents the mod_busy bits from changing.
7786 * (mod_busy can only be changed with mod_lock held.)
7787 */
7788 mutex_enter(&mod_lock);
7789
7790 ctl = &modules;
7791 do {
7792 if (ctl->mod_busy || ctl->mod_mp == NULL)
7793 continue;
7794
7795 prv->dtpv_pops.dtps_provide_module(prv->dtpv_arg, ctl);
7796
7797 } while ((ctl = ctl->mod_next) != &modules);
7798
7799 mutex_exit(&mod_lock);
7800 } while (all && (prv = prv->dtpv_next) != NULL);
7801 }
7802
7803 /*
7804 * Iterate over each probe, and call the Framework-to-Provider API function
7805 * denoted by offs.
7806 */
7807 static void
7808 dtrace_probe_foreach(uintptr_t offs)
7809 {
7810 dtrace_provider_t *prov;
7811 void (*func)(void *, dtrace_id_t, void *);
7812 dtrace_probe_t *probe;
7813 dtrace_icookie_t cookie;
7814 int i;
7815
7816 /*
7817 * We disable interrupts to walk through the probe array. This is
7818 * safe -- the dtrace_sync() in dtrace_unregister() assures that we
7819 * won't see stale data.
7820 */
7821 cookie = dtrace_interrupt_disable();
7822
7823 for (i = 0; i < dtrace_nprobes; i++) {
7824 if ((probe = dtrace_probes[i]) == NULL)
7825 continue;
7826
7827 if (probe->dtpr_ecb == NULL) {
7828 /*
7829 * This probe isn't enabled -- don't call the function.
7830 */
7831 continue;
7832 }
7833
7834 prov = probe->dtpr_provider;
7835 func = *((void(**)(void *, dtrace_id_t, void *))
7836 ((uintptr_t)&prov->dtpv_pops + offs));
7837
7838 func(prov->dtpv_arg, i + 1, probe->dtpr_arg);
7839 }
7840
7841 dtrace_interrupt_enable(cookie);
7842 }
7843
7844 static int
7845 dtrace_probe_enable(const dtrace_probedesc_t *desc, dtrace_enabling_t *enab)
7846 {
7847 dtrace_probekey_t pkey;
7848 uint32_t priv;
7849 uid_t uid;
7850 zoneid_t zoneid;
7851
7852 ASSERT(MUTEX_HELD(&dtrace_lock));
7853 dtrace_ecb_create_cache = NULL;
7854
7855 if (desc == NULL) {
7856 /*
7857 * If we're passed a NULL description, we're being asked to
7858 * create an ECB with a NULL probe.
7859 */
7860 (void) dtrace_ecb_create_enable(NULL, enab);
7861 return (0);
7862 }
7863
7864 dtrace_probekey(desc, &pkey);
7865 dtrace_cred2priv(enab->dten_vstate->dtvs_state->dts_cred.dcr_cred,
7866 &priv, &uid, &zoneid);
7867
7868 return (dtrace_match(&pkey, priv, uid, zoneid, dtrace_ecb_create_enable,
7869 enab));
7870 }
7871
7872 /*
7873 * DTrace Helper Provider Functions
7874 */
7875 static void
7876 dtrace_dofattr2attr(dtrace_attribute_t *attr, const dof_attr_t dofattr)
7877 {
7878 attr->dtat_name = DOF_ATTR_NAME(dofattr);
7879 attr->dtat_data = DOF_ATTR_DATA(dofattr);
7880 attr->dtat_class = DOF_ATTR_CLASS(dofattr);
7881 }
7882
7883 static void
7884 dtrace_dofprov2hprov(dtrace_helper_provdesc_t *hprov,
7885 const dof_provider_t *dofprov, char *strtab)
7886 {
7887 hprov->dthpv_provname = strtab + dofprov->dofpv_name;
7888 dtrace_dofattr2attr(&hprov->dthpv_pattr.dtpa_provider,
7889 dofprov->dofpv_provattr);
7890 dtrace_dofattr2attr(&hprov->dthpv_pattr.dtpa_mod,
7891 dofprov->dofpv_modattr);
7892 dtrace_dofattr2attr(&hprov->dthpv_pattr.dtpa_func,
7893 dofprov->dofpv_funcattr);
7894 dtrace_dofattr2attr(&hprov->dthpv_pattr.dtpa_name,
7895 dofprov->dofpv_nameattr);
7896 dtrace_dofattr2attr(&hprov->dthpv_pattr.dtpa_args,
7897 dofprov->dofpv_argsattr);
7898 }
7899
7900 static void
7901 dtrace_helper_provide_one(dof_helper_t *dhp, dof_sec_t *sec, pid_t pid)
7902 {
7903 uintptr_t daddr = (uintptr_t)dhp->dofhp_dof;
7904 dof_hdr_t *dof = (dof_hdr_t *)daddr;
7905 dof_sec_t *str_sec, *prb_sec, *arg_sec, *off_sec, *enoff_sec;
7906 dof_provider_t *provider;
7907 dof_probe_t *probe;
7908 uint32_t *off, *enoff;
7909 uint8_t *arg;
7910 char *strtab;
7911 uint_t i, nprobes;
7912 dtrace_helper_provdesc_t dhpv;
7913 dtrace_helper_probedesc_t dhpb;
7914 dtrace_meta_t *meta = dtrace_meta_pid;
7915 dtrace_mops_t *mops = &meta->dtm_mops;
7916 void *parg;
7917
7918 provider = (dof_provider_t *)(uintptr_t)(daddr + sec->dofs_offset);
7919 str_sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff +
7920 provider->dofpv_strtab * dof->dofh_secsize);
7921 prb_sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff +
7922 provider->dofpv_probes * dof->dofh_secsize);
7923 arg_sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff +
7924 provider->dofpv_prargs * dof->dofh_secsize);
7925 off_sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff +
7926 provider->dofpv_proffs * dof->dofh_secsize);
7927
7928 strtab = (char *)(uintptr_t)(daddr + str_sec->dofs_offset);
7929 off = (uint32_t *)(uintptr_t)(daddr + off_sec->dofs_offset);
7930 arg = (uint8_t *)(uintptr_t)(daddr + arg_sec->dofs_offset);
7931 enoff = NULL;
7932
7933 /*
7934 * See dtrace_helper_provider_validate().
7935 */
7936 if (dof->dofh_ident[DOF_ID_VERSION] != DOF_VERSION_1 &&
7937 provider->dofpv_prenoffs != DOF_SECT_NONE) {
7938 enoff_sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff +
7939 provider->dofpv_prenoffs * dof->dofh_secsize);
7940 enoff = (uint32_t *)(uintptr_t)(daddr + enoff_sec->dofs_offset);
7941 }
7942
7943 nprobes = prb_sec->dofs_size / prb_sec->dofs_entsize;
7944
7945 /*
7946 * Create the provider.
7947 */
7948 dtrace_dofprov2hprov(&dhpv, provider, strtab);
7949
7950 if ((parg = mops->dtms_provide_pid(meta->dtm_arg, &dhpv, pid)) == NULL)
7951 return;
7952
7953 meta->dtm_count++;
7954
7955 /*
7956 * Create the probes.
7957 */
7958 for (i = 0; i < nprobes; i++) {
7959 probe = (dof_probe_t *)(uintptr_t)(daddr +
7960 prb_sec->dofs_offset + i * prb_sec->dofs_entsize);
7961
7962 dhpb.dthpb_mod = dhp->dofhp_mod;
7963 dhpb.dthpb_func = strtab + probe->dofpr_func;
7964 dhpb.dthpb_name = strtab + probe->dofpr_name;
7965 dhpb.dthpb_base = probe->dofpr_addr;
7966 dhpb.dthpb_offs = off + probe->dofpr_offidx;
7967 dhpb.dthpb_noffs = probe->dofpr_noffs;
7968 if (enoff != NULL) {
7969 dhpb.dthpb_enoffs = enoff + probe->dofpr_enoffidx;
7970 dhpb.dthpb_nenoffs = probe->dofpr_nenoffs;
7971 } else {
7972 dhpb.dthpb_enoffs = NULL;
7973 dhpb.dthpb_nenoffs = 0;
7974 }
7975 dhpb.dthpb_args = arg + probe->dofpr_argidx;
7976 dhpb.dthpb_nargc = probe->dofpr_nargc;
7977 dhpb.dthpb_xargc = probe->dofpr_xargc;
7978 dhpb.dthpb_ntypes = strtab + probe->dofpr_nargv;
7979 dhpb.dthpb_xtypes = strtab + probe->dofpr_xargv;
7980
7981 mops->dtms_create_probe(meta->dtm_arg, parg, &dhpb);
7982 }
7983 }
7984
7985 static void
7986 dtrace_helper_provide(dof_helper_t *dhp, pid_t pid)
7987 {
7988 uintptr_t daddr = (uintptr_t)dhp->dofhp_dof;
7989 dof_hdr_t *dof = (dof_hdr_t *)daddr;
7990 int i;
7991
7992 ASSERT(MUTEX_HELD(&dtrace_meta_lock));
7993
7994 for (i = 0; i < dof->dofh_secnum; i++) {
7995 dof_sec_t *sec = (dof_sec_t *)(uintptr_t)(daddr +
7996 dof->dofh_secoff + i * dof->dofh_secsize);
7997
7998 if (sec->dofs_type != DOF_SECT_PROVIDER)
7999 continue;
8000
8001 dtrace_helper_provide_one(dhp, sec, pid);
8002 }
8003
8004 /*
8005 * We may have just created probes, so we must now rematch against
8006 * any retained enablings. Note that this call will acquire both
8007 * cpu_lock and dtrace_lock; the fact that we are holding
8008 * dtrace_meta_lock now is what defines the ordering with respect to
8009 * these three locks.
8010 */
8011 dtrace_enabling_matchall();
8012 }
8013
8014 static void
8015 dtrace_helper_provider_remove_one(dof_helper_t *dhp, dof_sec_t *sec, pid_t pid)
8016 {
8017 uintptr_t daddr = (uintptr_t)dhp->dofhp_dof;
8018 dof_hdr_t *dof = (dof_hdr_t *)daddr;
8019 dof_sec_t *str_sec;
8020 dof_provider_t *provider;
8021 char *strtab;
8022 dtrace_helper_provdesc_t dhpv;
8023 dtrace_meta_t *meta = dtrace_meta_pid;
8024 dtrace_mops_t *mops = &meta->dtm_mops;
8025
8026 provider = (dof_provider_t *)(uintptr_t)(daddr + sec->dofs_offset);
8027 str_sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff +
8028 provider->dofpv_strtab * dof->dofh_secsize);
8029
8030 strtab = (char *)(uintptr_t)(daddr + str_sec->dofs_offset);
8031
8032 /*
8033 * Create the provider.
8034 */
8035 dtrace_dofprov2hprov(&dhpv, provider, strtab);
8036
8037 mops->dtms_remove_pid(meta->dtm_arg, &dhpv, pid);
8038
8039 meta->dtm_count--;
8040 }
8041
8042 static void
8043 dtrace_helper_provider_remove(dof_helper_t *dhp, pid_t pid)
8044 {
8045 uintptr_t daddr = (uintptr_t)dhp->dofhp_dof;
8046 dof_hdr_t *dof = (dof_hdr_t *)daddr;
8047 int i;
8048
8049 ASSERT(MUTEX_HELD(&dtrace_meta_lock));
8050
8051 for (i = 0; i < dof->dofh_secnum; i++) {
8052 dof_sec_t *sec = (dof_sec_t *)(uintptr_t)(daddr +
8053 dof->dofh_secoff + i * dof->dofh_secsize);
8054
8055 if (sec->dofs_type != DOF_SECT_PROVIDER)
8056 continue;
8057
8058 dtrace_helper_provider_remove_one(dhp, sec, pid);
8059 }
8060 }
8061
8062 /*
8063 * DTrace Meta Provider-to-Framework API Functions
8064 *
8065 * These functions implement the Meta Provider-to-Framework API, as described
8066 * in <sys/dtrace.h>.
8067 */
8068 int
8069 dtrace_meta_register(const char *name, const dtrace_mops_t *mops, void *arg,
8070 dtrace_meta_provider_id_t *idp)
8071 {
8072 dtrace_meta_t *meta;
8073 dtrace_helpers_t *help, *next;
8074 int i;
8075
8076 *idp = DTRACE_METAPROVNONE;
8077
8078 /*
8079 * We strictly don't need the name, but we hold onto it for
8080 * debuggability. All hail error queues!
8081 */
8082 if (name == NULL) {
8083 cmn_err(CE_WARN, "failed to register meta-provider: "
8084 "invalid name");
8085 return (EINVAL);
8086 }
8087
8088 if (mops == NULL ||
8089 mops->dtms_create_probe == NULL ||
8090 mops->dtms_provide_pid == NULL ||
8091 mops->dtms_remove_pid == NULL) {
8092 cmn_err(CE_WARN, "failed to register meta-register %s: "
8093 "invalid ops", name);
8094 return (EINVAL);
8095 }
8096
8097 meta = kmem_zalloc(sizeof (dtrace_meta_t), KM_SLEEP);
8098 meta->dtm_mops = *mops;
8099 meta->dtm_name = kmem_alloc(strlen(name) + 1, KM_SLEEP);
8100 (void) strcpy(meta->dtm_name, name);
8101 meta->dtm_arg = arg;
8102
8103 mutex_enter(&dtrace_meta_lock);
8104 mutex_enter(&dtrace_lock);
8105
8106 if (dtrace_meta_pid != NULL) {
8107 mutex_exit(&dtrace_lock);
8108 mutex_exit(&dtrace_meta_lock);
8109 cmn_err(CE_WARN, "failed to register meta-register %s: "
8110 "user-land meta-provider exists", name);
8111 kmem_free(meta->dtm_name, strlen(meta->dtm_name) + 1);
8112 kmem_free(meta, sizeof (dtrace_meta_t));
8113 return (EINVAL);
8114 }
8115
8116 dtrace_meta_pid = meta;
8117 *idp = (dtrace_meta_provider_id_t)meta;
8118
8119 /*
8120 * If there are providers and probes ready to go, pass them
8121 * off to the new meta provider now.
8122 */
8123
8124 help = dtrace_deferred_pid;
8125 dtrace_deferred_pid = NULL;
8126
8127 mutex_exit(&dtrace_lock);
8128
8129 while (help != NULL) {
8130 for (i = 0; i < help->dthps_nprovs; i++) {
8131 dtrace_helper_provide(&help->dthps_provs[i]->dthp_prov,
8132 help->dthps_pid);
8133 }
8134
8135 next = help->dthps_next;
8136 help->dthps_next = NULL;
8137 help->dthps_prev = NULL;
8138 help->dthps_deferred = 0;
8139 help = next;
8140 }
8141
8142 mutex_exit(&dtrace_meta_lock);
8143
8144 return (0);
8145 }
8146
8147 int
8148 dtrace_meta_unregister(dtrace_meta_provider_id_t id)
8149 {
8150 dtrace_meta_t **pp, *old = (dtrace_meta_t *)id;
8151
8152 mutex_enter(&dtrace_meta_lock);
8153 mutex_enter(&dtrace_lock);
8154
8155 if (old == dtrace_meta_pid) {
8156 pp = &dtrace_meta_pid;
8157 } else {
8158 panic("attempt to unregister non-existent "
8159 "dtrace meta-provider %p\n", (void *)old);
8160 }
8161
8162 if (old->dtm_count != 0) {
8163 mutex_exit(&dtrace_lock);
8164 mutex_exit(&dtrace_meta_lock);
8165 return (EBUSY);
8166 }
8167
8168 *pp = NULL;
8169
8170 mutex_exit(&dtrace_lock);
8171 mutex_exit(&dtrace_meta_lock);
8172
8173 kmem_free(old->dtm_name, strlen(old->dtm_name) + 1);
8174 kmem_free(old, sizeof (dtrace_meta_t));
8175
8176 return (0);
8177 }
8178
8179
8180 /*
8181 * DTrace DIF Object Functions
8182 */
8183 static int
8184 dtrace_difo_err(uint_t pc, const char *format, ...)
8185 {
8186 if (dtrace_err_verbose) {
8187 va_list alist;
8188
8189 (void) uprintf("dtrace DIF object error: [%u]: ", pc);
8190 va_start(alist, format);
8191 (void) vuprintf(format, alist);
8192 va_end(alist);
8193 }
8194
8195 #ifdef DTRACE_ERRDEBUG
8196 dtrace_errdebug(format);
8197 #endif
8198 return (1);
8199 }
8200
8201 /*
8202 * Validate a DTrace DIF object by checking the IR instructions. The following
8203 * rules are currently enforced by dtrace_difo_validate():
8204 *
8205 * 1. Each instruction must have a valid opcode
8206 * 2. Each register, string, variable, or subroutine reference must be valid
8207 * 3. No instruction can modify register %r0 (must be zero)
8208 * 4. All instruction reserved bits must be set to zero
8209 * 5. The last instruction must be a "ret" instruction
8210 * 6. All branch targets must reference a valid instruction _after_ the branch
8211 */
8212 static int
8213 dtrace_difo_validate(dtrace_difo_t *dp, dtrace_vstate_t *vstate, uint_t nregs,
8214 cred_t *cr)
8215 {
8216 int err = 0, i;
8217 int (*efunc)(uint_t pc, const char *, ...) = dtrace_difo_err;
8218 int kcheckload;
8219 uint_t pc;
8220
8221 kcheckload = cr == NULL ||
8222 (vstate->dtvs_state->dts_cred.dcr_visible & DTRACE_CRV_KERNEL) == 0;
8223
8224 dp->dtdo_destructive = 0;
8225
8226 for (pc = 0; pc < dp->dtdo_len && err == 0; pc++) {
8227 dif_instr_t instr = dp->dtdo_buf[pc];
8228
8229 uint_t r1 = DIF_INSTR_R1(instr);
8230 uint_t r2 = DIF_INSTR_R2(instr);
8231 uint_t rd = DIF_INSTR_RD(instr);
8232 uint_t rs = DIF_INSTR_RS(instr);
8233 uint_t label = DIF_INSTR_LABEL(instr);
8234 uint_t v = DIF_INSTR_VAR(instr);
8235 uint_t subr = DIF_INSTR_SUBR(instr);
8236 uint_t type = DIF_INSTR_TYPE(instr);
8237 uint_t op = DIF_INSTR_OP(instr);
8238
8239 switch (op) {
8240 case DIF_OP_OR:
8241 case DIF_OP_XOR:
8242 case DIF_OP_AND:
8243 case DIF_OP_SLL:
8244 case DIF_OP_SRL:
8245 case DIF_OP_SRA:
8246 case DIF_OP_SUB:
8247 case DIF_OP_ADD:
8248 case DIF_OP_MUL:
8249 case DIF_OP_SDIV:
8250 case DIF_OP_UDIV:
8251 case DIF_OP_SREM:
8252 case DIF_OP_UREM:
8253 case DIF_OP_COPYS:
8254 if (r1 >= nregs)
8255 err += efunc(pc, "invalid register %u\n", r1);
8256 if (r2 >= nregs)
8257 err += efunc(pc, "invalid register %u\n", r2);
8258 if (rd >= nregs)
8259 err += efunc(pc, "invalid register %u\n", rd);
8260 if (rd == 0)
8261 err += efunc(pc, "cannot write to %r0\n");
8262 break;
8263 case DIF_OP_NOT:
8264 case DIF_OP_MOV:
8265 case DIF_OP_ALLOCS:
8266 if (r1 >= nregs)
8267 err += efunc(pc, "invalid register %u\n", r1);
8268 if (r2 != 0)
8269 err += efunc(pc, "non-zero reserved bits\n");
8270 if (rd >= nregs)
8271 err += efunc(pc, "invalid register %u\n", rd);
8272 if (rd == 0)
8273 err += efunc(pc, "cannot write to %r0\n");
8274 break;
8275 case DIF_OP_LDSB:
8276 case DIF_OP_LDSH:
8277 case DIF_OP_LDSW:
8278 case DIF_OP_LDUB:
8279 case DIF_OP_LDUH:
8280 case DIF_OP_LDUW:
8281 case DIF_OP_LDX:
8282 if (r1 >= nregs)
8283 err += efunc(pc, "invalid register %u\n", r1);
8284 if (r2 != 0)
8285 err += efunc(pc, "non-zero reserved bits\n");
8286 if (rd >= nregs)
8287 err += efunc(pc, "invalid register %u\n", rd);
8288 if (rd == 0)
8289 err += efunc(pc, "cannot write to %r0\n");
8290 if (kcheckload)
8291 dp->dtdo_buf[pc] = DIF_INSTR_LOAD(op +
8292 DIF_OP_RLDSB - DIF_OP_LDSB, r1, rd);
8293 break;
8294 case DIF_OP_RLDSB:
8295 case DIF_OP_RLDSH:
8296 case DIF_OP_RLDSW:
8297 case DIF_OP_RLDUB:
8298 case DIF_OP_RLDUH:
8299 case DIF_OP_RLDUW:
8300 case DIF_OP_RLDX:
8301 if (r1 >= nregs)
8302 err += efunc(pc, "invalid register %u\n", r1);
8303 if (r2 != 0)
8304 err += efunc(pc, "non-zero reserved bits\n");
8305 if (rd >= nregs)
8306 err += efunc(pc, "invalid register %u\n", rd);
8307 if (rd == 0)
8308 err += efunc(pc, "cannot write to %r0\n");
8309 break;
8310 case DIF_OP_ULDSB:
8311 case DIF_OP_ULDSH:
8312 case DIF_OP_ULDSW:
8313 case DIF_OP_ULDUB:
8314 case DIF_OP_ULDUH:
8315 case DIF_OP_ULDUW:
8316 case DIF_OP_ULDX:
8317 if (r1 >= nregs)
8318 err += efunc(pc, "invalid register %u\n", r1);
8319 if (r2 != 0)
8320 err += efunc(pc, "non-zero reserved bits\n");
8321 if (rd >= nregs)
8322 err += efunc(pc, "invalid register %u\n", rd);
8323 if (rd == 0)
8324 err += efunc(pc, "cannot write to %r0\n");
8325 break;
8326 case DIF_OP_STB:
8327 case DIF_OP_STH:
8328 case DIF_OP_STW:
8329 case DIF_OP_STX:
8330 if (r1 >= nregs)
8331 err += efunc(pc, "invalid register %u\n", r1);
8332 if (r2 != 0)
8333 err += efunc(pc, "non-zero reserved bits\n");
8334 if (rd >= nregs)
8335 err += efunc(pc, "invalid register %u\n", rd);
8336 if (rd == 0)
8337 err += efunc(pc, "cannot write to 0 address\n");
8338 break;
8339 case DIF_OP_CMP:
8340 case DIF_OP_SCMP:
8341 if (r1 >= nregs)
8342 err += efunc(pc, "invalid register %u\n", r1);
8343 if (r2 >= nregs)
8344 err += efunc(pc, "invalid register %u\n", r2);
8345 if (rd != 0)
8346 err += efunc(pc, "non-zero reserved bits\n");
8347 break;
8348 case DIF_OP_TST:
8349 if (r1 >= nregs)
8350 err += efunc(pc, "invalid register %u\n", r1);
8351 if (r2 != 0 || rd != 0)
8352 err += efunc(pc, "non-zero reserved bits\n");
8353 break;
8354 case DIF_OP_BA:
8355 case DIF_OP_BE:
8356 case DIF_OP_BNE:
8357 case DIF_OP_BG:
8358 case DIF_OP_BGU:
8359 case DIF_OP_BGE:
8360 case DIF_OP_BGEU:
8361 case DIF_OP_BL:
8362 case DIF_OP_BLU:
8363 case DIF_OP_BLE:
8364 case DIF_OP_BLEU:
8365 if (label >= dp->dtdo_len) {
8366 err += efunc(pc, "invalid branch target %u\n",
8367 label);
8368 }
8369 if (label <= pc) {
8370 err += efunc(pc, "backward branch to %u\n",
8371 label);
8372 }
8373 break;
8374 case DIF_OP_RET:
8375 if (r1 != 0 || r2 != 0)
8376 err += efunc(pc, "non-zero reserved bits\n");
8377 if (rd >= nregs)
8378 err += efunc(pc, "invalid register %u\n", rd);
8379 break;
8380 case DIF_OP_NOP:
8381 case DIF_OP_POPTS:
8382 case DIF_OP_FLUSHTS:
8383 if (r1 != 0 || r2 != 0 || rd != 0)
8384 err += efunc(pc, "non-zero reserved bits\n");
8385 break;
8386 case DIF_OP_SETX:
8387 if (DIF_INSTR_INTEGER(instr) >= dp->dtdo_intlen) {
8388 err += efunc(pc, "invalid integer ref %u\n",
8389 DIF_INSTR_INTEGER(instr));
8390 }
8391 if (rd >= nregs)
8392 err += efunc(pc, "invalid register %u\n", rd);
8393 if (rd == 0)
8394 err += efunc(pc, "cannot write to %r0\n");
8395 break;
8396 case DIF_OP_SETS:
8397 if (DIF_INSTR_STRING(instr) >= dp->dtdo_strlen) {
8398 err += efunc(pc, "invalid string ref %u\n",
8399 DIF_INSTR_STRING(instr));
8400 }
8401 if (rd >= nregs)
8402 err += efunc(pc, "invalid register %u\n", rd);
8403 if (rd == 0)
8404 err += efunc(pc, "cannot write to %r0\n");
8405 break;
8406 case DIF_OP_LDGA:
8407 case DIF_OP_LDTA:
8408 if (r1 > DIF_VAR_ARRAY_MAX)
8409 err += efunc(pc, "invalid array %u\n", r1);
8410 if (r2 >= nregs)
8411 err += efunc(pc, "invalid register %u\n", r2);
8412 if (rd >= nregs)
8413 err += efunc(pc, "invalid register %u\n", rd);
8414 if (rd == 0)
8415 err += efunc(pc, "cannot write to %r0\n");
8416 break;
8417 case DIF_OP_LDGS:
8418 case DIF_OP_LDTS:
8419 case DIF_OP_LDLS:
8420 case DIF_OP_LDGAA:
8421 case DIF_OP_LDTAA:
8422 if (v < DIF_VAR_OTHER_MIN || v > DIF_VAR_OTHER_MAX)
8423 err += efunc(pc, "invalid variable %u\n", v);
8424 if (rd >= nregs)
8425 err += efunc(pc, "invalid register %u\n", rd);
8426 if (rd == 0)
8427 err += efunc(pc, "cannot write to %r0\n");
8428 break;
8429 case DIF_OP_STGS:
8430 case DIF_OP_STTS:
8431 case DIF_OP_STLS:
8432 case DIF_OP_STGAA:
8433 case DIF_OP_STTAA:
8434 if (v < DIF_VAR_OTHER_UBASE || v > DIF_VAR_OTHER_MAX)
8435 err += efunc(pc, "invalid variable %u\n", v);
8436 if (rs >= nregs)
8437 err += efunc(pc, "invalid register %u\n", rd);
8438 break;
8439 case DIF_OP_CALL:
8440 if (subr > DIF_SUBR_MAX)
8441 err += efunc(pc, "invalid subr %u\n", subr);
8442 if (rd >= nregs)
8443 err += efunc(pc, "invalid register %u\n", rd);
8444 if (rd == 0)
8445 err += efunc(pc, "cannot write to %r0\n");
8446
8447 if (subr == DIF_SUBR_COPYOUT ||
8448 subr == DIF_SUBR_COPYOUTSTR) {
8449 dp->dtdo_destructive = 1;
8450 }
8451 break;
8452 case DIF_OP_PUSHTR:
8453 if (type != DIF_TYPE_STRING && type != DIF_TYPE_CTF)
8454 err += efunc(pc, "invalid ref type %u\n", type);
8455 if (r2 >= nregs)
8456 err += efunc(pc, "invalid register %u\n", r2);
8457 if (rs >= nregs)
8458 err += efunc(pc, "invalid register %u\n", rs);
8459 break;
8460 case DIF_OP_PUSHTV:
8461 if (type != DIF_TYPE_CTF)
8462 err += efunc(pc, "invalid val type %u\n", type);
8463 if (r2 >= nregs)
8464 err += efunc(pc, "invalid register %u\n", r2);
8465 if (rs >= nregs)
8466 err += efunc(pc, "invalid register %u\n", rs);
8467 break;
8468 default:
8469 err += efunc(pc, "invalid opcode %u\n",
8470 DIF_INSTR_OP(instr));
8471 }
8472 }
8473
8474 if (dp->dtdo_len != 0 &&
8475 DIF_INSTR_OP(dp->dtdo_buf[dp->dtdo_len - 1]) != DIF_OP_RET) {
8476 err += efunc(dp->dtdo_len - 1,
8477 "expected 'ret' as last DIF instruction\n");
8478 }
8479
8480 if (!(dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF)) {
8481 /*
8482 * If we're not returning by reference, the size must be either
8483 * 0 or the size of one of the base types.
8484 */
8485 switch (dp->dtdo_rtype.dtdt_size) {
8486 case 0:
8487 case sizeof (uint8_t):
8488 case sizeof (uint16_t):
8489 case sizeof (uint32_t):
8490 case sizeof (uint64_t):
8491 break;
8492
8493 default:
8494 err += efunc(dp->dtdo_len - 1, "bad return size\n");
8495 }
8496 }
8497
8498 for (i = 0; i < dp->dtdo_varlen && err == 0; i++) {
8499 dtrace_difv_t *v = &dp->dtdo_vartab[i], *existing = NULL;
8500 dtrace_diftype_t *vt, *et;
8501 uint_t id, ndx;
8502
8503 if (v->dtdv_scope != DIFV_SCOPE_GLOBAL &&
8504 v->dtdv_scope != DIFV_SCOPE_THREAD &&
8505 v->dtdv_scope != DIFV_SCOPE_LOCAL) {
8506 err += efunc(i, "unrecognized variable scope %d\n",
8507 v->dtdv_scope);
8508 break;
8509 }
8510
8511 if (v->dtdv_kind != DIFV_KIND_ARRAY &&
8512 v->dtdv_kind != DIFV_KIND_SCALAR) {
8513 err += efunc(i, "unrecognized variable type %d\n",
8514 v->dtdv_kind);
8515 break;
8516 }
8517
8518 if ((id = v->dtdv_id) > DIF_VARIABLE_MAX) {
8519 err += efunc(i, "%d exceeds variable id limit\n", id);
8520 break;
8521 }
8522
8523 if (id < DIF_VAR_OTHER_UBASE)
8524 continue;
8525
8526 /*
8527 * For user-defined variables, we need to check that this
8528 * definition is identical to any previous definition that we
8529 * encountered.
8530 */
8531 ndx = id - DIF_VAR_OTHER_UBASE;
8532
8533 switch (v->dtdv_scope) {
8534 case DIFV_SCOPE_GLOBAL:
8535 if (ndx < vstate->dtvs_nglobals) {
8536 dtrace_statvar_t *svar;
8537
8538 if ((svar = vstate->dtvs_globals[ndx]) != NULL)
8539 existing = &svar->dtsv_var;
8540 }
8541
8542 break;
8543
8544 case DIFV_SCOPE_THREAD:
8545 if (ndx < vstate->dtvs_ntlocals)
8546 existing = &vstate->dtvs_tlocals[ndx];
8547 break;
8548
8549 case DIFV_SCOPE_LOCAL:
8550 if (ndx < vstate->dtvs_nlocals) {
8551 dtrace_statvar_t *svar;
8552
8553 if ((svar = vstate->dtvs_locals[ndx]) != NULL)
8554 existing = &svar->dtsv_var;
8555 }
8556
8557 break;
8558 }
8559
8560 vt = &v->dtdv_type;
8561
8562 if (vt->dtdt_flags & DIF_TF_BYREF) {
8563 if (vt->dtdt_size == 0) {
8564 err += efunc(i, "zero-sized variable\n");
8565 break;
8566 }
8567
8568 if (v->dtdv_scope == DIFV_SCOPE_GLOBAL &&
8569 vt->dtdt_size > dtrace_global_maxsize) {
8570 err += efunc(i, "oversized by-ref global\n");
8571 break;
8572 }
8573 }
8574
8575 if (existing == NULL || existing->dtdv_id == 0)
8576 continue;
8577
8578 ASSERT(existing->dtdv_id == v->dtdv_id);
8579 ASSERT(existing->dtdv_scope == v->dtdv_scope);
8580
8581 if (existing->dtdv_kind != v->dtdv_kind)
8582 err += efunc(i, "%d changed variable kind\n", id);
8583
8584 et = &existing->dtdv_type;
8585
8586 if (vt->dtdt_flags != et->dtdt_flags) {
8587 err += efunc(i, "%d changed variable type flags\n", id);
8588 break;
8589 }
8590
8591 if (vt->dtdt_size != 0 && vt->dtdt_size != et->dtdt_size) {
8592 err += efunc(i, "%d changed variable type size\n", id);
8593 break;
8594 }
8595 }
8596
8597 return (err);
8598 }
8599
8600 /*
8601 * Validate a DTrace DIF object that it is to be used as a helper. Helpers
8602 * are much more constrained than normal DIFOs. Specifically, they may
8603 * not:
8604 *
8605 * 1. Make calls to subroutines other than copyin(), copyinstr() or
8606 * miscellaneous string routines
8607 * 2. Access DTrace variables other than the args[] array, and the
8608 * curthread, pid, ppid, tid, execname, zonename, uid and gid variables.
8609 * 3. Have thread-local variables.
8610 * 4. Have dynamic variables.
8611 */
8612 static int
8613 dtrace_difo_validate_helper(dtrace_difo_t *dp)
8614 {
8615 int (*efunc)(uint_t pc, const char *, ...) = dtrace_difo_err;
8616 int err = 0;
8617 uint_t pc;
8618
8619 for (pc = 0; pc < dp->dtdo_len; pc++) {
8620 dif_instr_t instr = dp->dtdo_buf[pc];
8621
8622 uint_t v = DIF_INSTR_VAR(instr);
8623 uint_t subr = DIF_INSTR_SUBR(instr);
8624 uint_t op = DIF_INSTR_OP(instr);
8625
8626 switch (op) {
8627 case DIF_OP_OR:
8628 case DIF_OP_XOR:
8629 case DIF_OP_AND:
8630 case DIF_OP_SLL:
8631 case DIF_OP_SRL:
8632 case DIF_OP_SRA:
8633 case DIF_OP_SUB:
8634 case DIF_OP_ADD:
8635 case DIF_OP_MUL:
8636 case DIF_OP_SDIV:
8637 case DIF_OP_UDIV:
8638 case DIF_OP_SREM:
8639 case DIF_OP_UREM:
8640 case DIF_OP_COPYS:
8641 case DIF_OP_NOT:
8642 case DIF_OP_MOV:
8643 case DIF_OP_RLDSB:
8644 case DIF_OP_RLDSH:
8645 case DIF_OP_RLDSW:
8646 case DIF_OP_RLDUB:
8647 case DIF_OP_RLDUH:
8648 case DIF_OP_RLDUW:
8649 case DIF_OP_RLDX:
8650 case DIF_OP_ULDSB:
8651 case DIF_OP_ULDSH:
8652 case DIF_OP_ULDSW:
8653 case DIF_OP_ULDUB:
8654 case DIF_OP_ULDUH:
8655 case DIF_OP_ULDUW:
8656 case DIF_OP_ULDX:
8657 case DIF_OP_STB:
8658 case DIF_OP_STH:
8659 case DIF_OP_STW:
8660 case DIF_OP_STX:
8661 case DIF_OP_ALLOCS:
8662 case DIF_OP_CMP:
8663 case DIF_OP_SCMP:
8664 case DIF_OP_TST:
8665 case DIF_OP_BA:
8666 case DIF_OP_BE:
8667 case DIF_OP_BNE:
8668 case DIF_OP_BG:
8669 case DIF_OP_BGU:
8670 case DIF_OP_BGE:
8671 case DIF_OP_BGEU:
8672 case DIF_OP_BL:
8673 case DIF_OP_BLU:
8674 case DIF_OP_BLE:
8675 case DIF_OP_BLEU:
8676 case DIF_OP_RET:
8677 case DIF_OP_NOP:
8678 case DIF_OP_POPTS:
8679 case DIF_OP_FLUSHTS:
8680 case DIF_OP_SETX:
8681 case DIF_OP_SETS:
8682 case DIF_OP_LDGA:
8683 case DIF_OP_LDLS:
8684 case DIF_OP_STGS:
8685 case DIF_OP_STLS:
8686 case DIF_OP_PUSHTR:
8687 case DIF_OP_PUSHTV:
8688 break;
8689
8690 case DIF_OP_LDGS:
8691 if (v >= DIF_VAR_OTHER_UBASE)
8692 break;
8693
8694 if (v >= DIF_VAR_ARG0 && v <= DIF_VAR_ARG9)
8695 break;
8696
8697 if (v == DIF_VAR_CURTHREAD || v == DIF_VAR_PID ||
8698 v == DIF_VAR_PPID || v == DIF_VAR_TID ||
8699 v == DIF_VAR_EXECNAME || v == DIF_VAR_ZONENAME ||
8700 v == DIF_VAR_UID || v == DIF_VAR_GID)
8701 break;
8702
8703 err += efunc(pc, "illegal variable %u\n", v);
8704 break;
8705
8706 case DIF_OP_LDTA:
8707 case DIF_OP_LDTS:
8708 case DIF_OP_LDGAA:
8709 case DIF_OP_LDTAA:
8710 err += efunc(pc, "illegal dynamic variable load\n");
8711 break;
8712
8713 case DIF_OP_STTS:
8714 case DIF_OP_STGAA:
8715 case DIF_OP_STTAA:
8716 err += efunc(pc, "illegal dynamic variable store\n");
8717 break;
8718
8719 case DIF_OP_CALL:
8720 if (subr == DIF_SUBR_ALLOCA ||
8721 subr == DIF_SUBR_BCOPY ||
8722 subr == DIF_SUBR_COPYIN ||
8723 subr == DIF_SUBR_COPYINTO ||
8724 subr == DIF_SUBR_COPYINSTR ||
8725 subr == DIF_SUBR_INDEX ||
8726 subr == DIF_SUBR_INET_NTOA ||
8727 subr == DIF_SUBR_INET_NTOA6 ||
8728 subr == DIF_SUBR_INET_NTOP ||
8729 subr == DIF_SUBR_LLTOSTR ||
8730 subr == DIF_SUBR_RINDEX ||
8731 subr == DIF_SUBR_STRCHR ||
8732 subr == DIF_SUBR_STRJOIN ||
8733 subr == DIF_SUBR_STRRCHR ||
8734 subr == DIF_SUBR_STRSTR ||
8735 subr == DIF_SUBR_HTONS ||
8736 subr == DIF_SUBR_HTONL ||
8737 subr == DIF_SUBR_HTONLL ||
8738 subr == DIF_SUBR_NTOHS ||
8739 subr == DIF_SUBR_NTOHL ||
8740 subr == DIF_SUBR_NTOHLL)
8741 break;
8742
8743 err += efunc(pc, "invalid subr %u\n", subr);
8744 break;
8745
8746 default:
8747 err += efunc(pc, "invalid opcode %u\n",
8748 DIF_INSTR_OP(instr));
8749 }
8750 }
8751
8752 return (err);
8753 }
8754
8755 /*
8756 * Returns 1 if the expression in the DIF object can be cached on a per-thread
8757 * basis; 0 if not.
8758 */
8759 static int
8760 dtrace_difo_cacheable(dtrace_difo_t *dp)
8761 {
8762 int i;
8763
8764 if (dp == NULL)
8765 return (0);
8766
8767 for (i = 0; i < dp->dtdo_varlen; i++) {
8768 dtrace_difv_t *v = &dp->dtdo_vartab[i];
8769
8770 if (v->dtdv_scope != DIFV_SCOPE_GLOBAL)
8771 continue;
8772
8773 switch (v->dtdv_id) {
8774 case DIF_VAR_CURTHREAD:
8775 case DIF_VAR_PID:
8776 case DIF_VAR_TID:
8777 case DIF_VAR_EXECNAME:
8778 case DIF_VAR_ZONENAME:
8779 break;
8780
8781 default:
8782 return (0);
8783 }
8784 }
8785
8786 /*
8787 * This DIF object may be cacheable. Now we need to look for any
8788 * array loading instructions, any memory loading instructions, or
8789 * any stores to thread-local variables.
8790 */
8791 for (i = 0; i < dp->dtdo_len; i++) {
8792 uint_t op = DIF_INSTR_OP(dp->dtdo_buf[i]);
8793
8794 if ((op >= DIF_OP_LDSB && op <= DIF_OP_LDX) ||
8795 (op >= DIF_OP_ULDSB && op <= DIF_OP_ULDX) ||
8796 (op >= DIF_OP_RLDSB && op <= DIF_OP_RLDX) ||
8797 op == DIF_OP_LDGA || op == DIF_OP_STTS)
8798 return (0);
8799 }
8800
8801 return (1);
8802 }
8803
8804 static void
8805 dtrace_difo_hold(dtrace_difo_t *dp)
8806 {
8807 int i;
8808
8809 ASSERT(MUTEX_HELD(&dtrace_lock));
8810
8811 dp->dtdo_refcnt++;
8812 ASSERT(dp->dtdo_refcnt != 0);
8813
8814 /*
8815 * We need to check this DIF object for references to the variable
8816 * DIF_VAR_VTIMESTAMP.
8817 */
8818 for (i = 0; i < dp->dtdo_varlen; i++) {
8819 dtrace_difv_t *v = &dp->dtdo_vartab[i];
8820
8821 if (v->dtdv_id != DIF_VAR_VTIMESTAMP)
8822 continue;
8823
8824 if (dtrace_vtime_references++ == 0)
8825 dtrace_vtime_enable();
8826 }
8827 }
8828
8829 /*
8830 * This routine calculates the dynamic variable chunksize for a given DIF
8831 * object. The calculation is not fool-proof, and can probably be tricked by
8832 * malicious DIF -- but it works for all compiler-generated DIF. Because this
8833 * calculation is likely imperfect, dtrace_dynvar() is able to gracefully fail
8834 * if a dynamic variable size exceeds the chunksize.
8835 */
8836 static void
8837 dtrace_difo_chunksize(dtrace_difo_t *dp, dtrace_vstate_t *vstate)
8838 {
8839 uint64_t sval;
8840 dtrace_key_t tupregs[DIF_DTR_NREGS + 2]; /* +2 for thread and id */
8841 const dif_instr_t *text = dp->dtdo_buf;
8842 uint_t pc, srd = 0;
8843 uint_t ttop = 0;
8844 size_t size, ksize;
8845 uint_t id, i;
8846
8847 for (pc = 0; pc < dp->dtdo_len; pc++) {
8848 dif_instr_t instr = text[pc];
8849 uint_t op = DIF_INSTR_OP(instr);
8850 uint_t rd = DIF_INSTR_RD(instr);
8851 uint_t r1 = DIF_INSTR_R1(instr);
8852 uint_t nkeys = 0;
8853 uchar_t scope;
8854
8855 dtrace_key_t *key = tupregs;
8856
8857 switch (op) {
8858 case DIF_OP_SETX:
8859 sval = dp->dtdo_inttab[DIF_INSTR_INTEGER(instr)];
8860 srd = rd;
8861 continue;
8862
8863 case DIF_OP_STTS:
8864 key = &tupregs[DIF_DTR_NREGS];
8865 key[0].dttk_size = 0;
8866 key[1].dttk_size = 0;
8867 nkeys = 2;
8868 scope = DIFV_SCOPE_THREAD;
8869 break;
8870
8871 case DIF_OP_STGAA:
8872 case DIF_OP_STTAA:
8873 nkeys = ttop;
8874
8875 if (DIF_INSTR_OP(instr) == DIF_OP_STTAA)
8876 key[nkeys++].dttk_size = 0;
8877
8878 key[nkeys++].dttk_size = 0;
8879
8880 if (op == DIF_OP_STTAA) {
8881 scope = DIFV_SCOPE_THREAD;
8882 } else {
8883 scope = DIFV_SCOPE_GLOBAL;
8884 }
8885
8886 break;
8887
8888 case DIF_OP_PUSHTR:
8889 if (ttop == DIF_DTR_NREGS)
8890 return;
8891
8892 if ((srd == 0 || sval == 0) && r1 == DIF_TYPE_STRING) {
8893 /*
8894 * If the register for the size of the "pushtr"
8895 * is %r0 (or the value is 0) and the type is
8896 * a string, we'll use the system-wide default
8897 * string size.
8898 */
8899 tupregs[ttop++].dttk_size =
8900 dtrace_strsize_default;
8901 } else {
8902 if (srd == 0)
8903 return;
8904
8905 tupregs[ttop++].dttk_size = sval;
8906 }
8907
8908 break;
8909
8910 case DIF_OP_PUSHTV:
8911 if (ttop == DIF_DTR_NREGS)
8912 return;
8913
8914 tupregs[ttop++].dttk_size = 0;
8915 break;
8916
8917 case DIF_OP_FLUSHTS:
8918 ttop = 0;
8919 break;
8920
8921 case DIF_OP_POPTS:
8922 if (ttop != 0)
8923 ttop--;
8924 break;
8925 }
8926
8927 sval = 0;
8928 srd = 0;
8929
8930 if (nkeys == 0)
8931 continue;
8932
8933 /*
8934 * We have a dynamic variable allocation; calculate its size.
8935 */
8936 for (ksize = 0, i = 0; i < nkeys; i++)
8937 ksize += P2ROUNDUP(key[i].dttk_size, sizeof (uint64_t));
8938
8939 size = sizeof (dtrace_dynvar_t);
8940 size += sizeof (dtrace_key_t) * (nkeys - 1);
8941 size += ksize;
8942
8943 /*
8944 * Now we need to determine the size of the stored data.
8945 */
8946 id = DIF_INSTR_VAR(instr);
8947
8948 for (i = 0; i < dp->dtdo_varlen; i++) {
8949 dtrace_difv_t *v = &dp->dtdo_vartab[i];
8950
8951 if (v->dtdv_id == id && v->dtdv_scope == scope) {
8952 size += v->dtdv_type.dtdt_size;
8953 break;
8954 }
8955 }
8956
8957 if (i == dp->dtdo_varlen)
8958 return;
8959
8960 /*
8961 * We have the size. If this is larger than the chunk size
8962 * for our dynamic variable state, reset the chunk size.
8963 */
8964 size = P2ROUNDUP(size, sizeof (uint64_t));
8965
8966 if (size > vstate->dtvs_dynvars.dtds_chunksize)
8967 vstate->dtvs_dynvars.dtds_chunksize = size;
8968 }
8969 }
8970
8971 static void
8972 dtrace_difo_init(dtrace_difo_t *dp, dtrace_vstate_t *vstate)
8973 {
8974 int i, oldsvars, osz, nsz, otlocals, ntlocals;
8975 uint_t id;
8976
8977 ASSERT(MUTEX_HELD(&dtrace_lock));
8978 ASSERT(dp->dtdo_buf != NULL && dp->dtdo_len != 0);
8979
8980 for (i = 0; i < dp->dtdo_varlen; i++) {
8981 dtrace_difv_t *v = &dp->dtdo_vartab[i];
8982 dtrace_statvar_t *svar, ***svarp;
8983 size_t dsize = 0;
8984 uint8_t scope = v->dtdv_scope;
8985 int *np;
8986
8987 if ((id = v->dtdv_id) < DIF_VAR_OTHER_UBASE)
8988 continue;
8989
8990 id -= DIF_VAR_OTHER_UBASE;
8991
8992 switch (scope) {
8993 case DIFV_SCOPE_THREAD:
8994 while (id >= (otlocals = vstate->dtvs_ntlocals)) {
8995 dtrace_difv_t *tlocals;
8996
8997 if ((ntlocals = (otlocals << 1)) == 0)
8998 ntlocals = 1;
8999
9000 osz = otlocals * sizeof (dtrace_difv_t);
9001 nsz = ntlocals * sizeof (dtrace_difv_t);
9002
9003 tlocals = kmem_zalloc(nsz, KM_SLEEP);
9004
9005 if (osz != 0) {
9006 bcopy(vstate->dtvs_tlocals,
9007 tlocals, osz);
9008 kmem_free(vstate->dtvs_tlocals, osz);
9009 }
9010
9011 vstate->dtvs_tlocals = tlocals;
9012 vstate->dtvs_ntlocals = ntlocals;
9013 }
9014
9015 vstate->dtvs_tlocals[id] = *v;
9016 continue;
9017
9018 case DIFV_SCOPE_LOCAL:
9019 np = &vstate->dtvs_nlocals;
9020 svarp = &vstate->dtvs_locals;
9021
9022 if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF)
9023 dsize = NCPU * (v->dtdv_type.dtdt_size +
9024 sizeof (uint64_t));
9025 else
9026 dsize = NCPU * sizeof (uint64_t);
9027
9028 break;
9029
9030 case DIFV_SCOPE_GLOBAL:
9031 np = &vstate->dtvs_nglobals;
9032 svarp = &vstate->dtvs_globals;
9033
9034 if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF)
9035 dsize = v->dtdv_type.dtdt_size +
9036 sizeof (uint64_t);
9037
9038 break;
9039
9040 default:
9041 ASSERT(0);
9042 }
9043
9044 while (id >= (oldsvars = *np)) {
9045 dtrace_statvar_t **statics;
9046 int newsvars, oldsize, newsize;
9047
9048 if ((newsvars = (oldsvars << 1)) == 0)
9049 newsvars = 1;
9050
9051 oldsize = oldsvars * sizeof (dtrace_statvar_t *);
9052 newsize = newsvars * sizeof (dtrace_statvar_t *);
9053
9054 statics = kmem_zalloc(newsize, KM_SLEEP);
9055
9056 if (oldsize != 0) {
9057 bcopy(*svarp, statics, oldsize);
9058 kmem_free(*svarp, oldsize);
9059 }
9060
9061 *svarp = statics;
9062 *np = newsvars;
9063 }
9064
9065 if ((svar = (*svarp)[id]) == NULL) {
9066 svar = kmem_zalloc(sizeof (dtrace_statvar_t), KM_SLEEP);
9067 svar->dtsv_var = *v;
9068
9069 if ((svar->dtsv_size = dsize) != 0) {
9070 svar->dtsv_data = (uint64_t)(uintptr_t)
9071 kmem_zalloc(dsize, KM_SLEEP);
9072 }
9073
9074 (*svarp)[id] = svar;
9075 }
9076
9077 svar->dtsv_refcnt++;
9078 }
9079
9080 dtrace_difo_chunksize(dp, vstate);
9081 dtrace_difo_hold(dp);
9082 }
9083
9084 static dtrace_difo_t *
9085 dtrace_difo_duplicate(dtrace_difo_t *dp, dtrace_vstate_t *vstate)
9086 {
9087 dtrace_difo_t *new;
9088 size_t sz;
9089
9090 ASSERT(dp->dtdo_buf != NULL);
9091 ASSERT(dp->dtdo_refcnt != 0);
9092
9093 new = kmem_zalloc(sizeof (dtrace_difo_t), KM_SLEEP);
9094
9095 ASSERT(dp->dtdo_buf != NULL);
9096 sz = dp->dtdo_len * sizeof (dif_instr_t);
9097 new->dtdo_buf = kmem_alloc(sz, KM_SLEEP);
9098 bcopy(dp->dtdo_buf, new->dtdo_buf, sz);
9099 new->dtdo_len = dp->dtdo_len;
9100
9101 if (dp->dtdo_strtab != NULL) {
9102 ASSERT(dp->dtdo_strlen != 0);
9103 new->dtdo_strtab = kmem_alloc(dp->dtdo_strlen, KM_SLEEP);
9104 bcopy(dp->dtdo_strtab, new->dtdo_strtab, dp->dtdo_strlen);
9105 new->dtdo_strlen = dp->dtdo_strlen;
9106 }
9107
9108 if (dp->dtdo_inttab != NULL) {
9109 ASSERT(dp->dtdo_intlen != 0);
9110 sz = dp->dtdo_intlen * sizeof (uint64_t);
9111 new->dtdo_inttab = kmem_alloc(sz, KM_SLEEP);
9112 bcopy(dp->dtdo_inttab, new->dtdo_inttab, sz);
9113 new->dtdo_intlen = dp->dtdo_intlen;
9114 }
9115
9116 if (dp->dtdo_vartab != NULL) {
9117 ASSERT(dp->dtdo_varlen != 0);
9118 sz = dp->dtdo_varlen * sizeof (dtrace_difv_t);
9119 new->dtdo_vartab = kmem_alloc(sz, KM_SLEEP);
9120 bcopy(dp->dtdo_vartab, new->dtdo_vartab, sz);
9121 new->dtdo_varlen = dp->dtdo_varlen;
9122 }
9123
9124 dtrace_difo_init(new, vstate);
9125 return (new);
9126 }
9127
9128 static void
9129 dtrace_difo_destroy(dtrace_difo_t *dp, dtrace_vstate_t *vstate)
9130 {
9131 int i;
9132
9133 ASSERT(dp->dtdo_refcnt == 0);
9134
9135 for (i = 0; i < dp->dtdo_varlen; i++) {
9136 dtrace_difv_t *v = &dp->dtdo_vartab[i];
9137 dtrace_statvar_t *svar, **svarp;
9138 uint_t id;
9139 uint8_t scope = v->dtdv_scope;
9140 int *np;
9141
9142 switch (scope) {
9143 case DIFV_SCOPE_THREAD:
9144 continue;
9145
9146 case DIFV_SCOPE_LOCAL:
9147 np = &vstate->dtvs_nlocals;
9148 svarp = vstate->dtvs_locals;
9149 break;
9150
9151 case DIFV_SCOPE_GLOBAL:
9152 np = &vstate->dtvs_nglobals;
9153 svarp = vstate->dtvs_globals;
9154 break;
9155
9156 default:
9157 ASSERT(0);
9158 }
9159
9160 if ((id = v->dtdv_id) < DIF_VAR_OTHER_UBASE)
9161 continue;
9162
9163 id -= DIF_VAR_OTHER_UBASE;
9164 ASSERT(id < *np);
9165
9166 svar = svarp[id];
9167 ASSERT(svar != NULL);
9168 ASSERT(svar->dtsv_refcnt > 0);
9169
9170 if (--svar->dtsv_refcnt > 0)
9171 continue;
9172
9173 if (svar->dtsv_size != 0) {
9174 ASSERT(svar->dtsv_data != NULL);
9175 kmem_free((void *)(uintptr_t)svar->dtsv_data,
9176 svar->dtsv_size);
9177 }
9178
9179 kmem_free(svar, sizeof (dtrace_statvar_t));
9180 svarp[id] = NULL;
9181 }
9182
9183 kmem_free(dp->dtdo_buf, dp->dtdo_len * sizeof (dif_instr_t));
9184 kmem_free(dp->dtdo_inttab, dp->dtdo_intlen * sizeof (uint64_t));
9185 kmem_free(dp->dtdo_strtab, dp->dtdo_strlen);
9186 kmem_free(dp->dtdo_vartab, dp->dtdo_varlen * sizeof (dtrace_difv_t));
9187
9188 kmem_free(dp, sizeof (dtrace_difo_t));
9189 }
9190
9191 static void
9192 dtrace_difo_release(dtrace_difo_t *dp, dtrace_vstate_t *vstate)
9193 {
9194 int i;
9195
9196 ASSERT(MUTEX_HELD(&dtrace_lock));
9197 ASSERT(dp->dtdo_refcnt != 0);
9198
9199 for (i = 0; i < dp->dtdo_varlen; i++) {
9200 dtrace_difv_t *v = &dp->dtdo_vartab[i];
9201
9202 if (v->dtdv_id != DIF_VAR_VTIMESTAMP)
9203 continue;
9204
9205 ASSERT(dtrace_vtime_references > 0);
9206 if (--dtrace_vtime_references == 0)
9207 dtrace_vtime_disable();
9208 }
9209
9210 if (--dp->dtdo_refcnt == 0)
9211 dtrace_difo_destroy(dp, vstate);
9212 }
9213
9214 /*
9215 * DTrace Format Functions
9216 */
9217 static uint16_t
9218 dtrace_format_add(dtrace_state_t *state, char *str)
9219 {
9220 char *fmt, **new;
9221 uint16_t ndx, len = strlen(str) + 1;
9222
9223 fmt = kmem_zalloc(len, KM_SLEEP);
9224 bcopy(str, fmt, len);
9225
9226 for (ndx = 0; ndx < state->dts_nformats; ndx++) {
9227 if (state->dts_formats[ndx] == NULL) {
9228 state->dts_formats[ndx] = fmt;
9229 return (ndx + 1);
9230 }
9231 }
9232
9233 if (state->dts_nformats == USHRT_MAX) {
9234 /*
9235 * This is only likely if a denial-of-service attack is being
9236 * attempted. As such, it's okay to fail silently here.
9237 */
9238 kmem_free(fmt, len);
9239 return (0);
9240 }
9241
9242 /*
9243 * For simplicity, we always resize the formats array to be exactly the
9244 * number of formats.
9245 */
9246 ndx = state->dts_nformats++;
9247 new = kmem_alloc((ndx + 1) * sizeof (char *), KM_SLEEP);
9248
9249 if (state->dts_formats != NULL) {
9250 ASSERT(ndx != 0);
9251 bcopy(state->dts_formats, new, ndx * sizeof (char *));
9252 kmem_free(state->dts_formats, ndx * sizeof (char *));
9253 }
9254
9255 state->dts_formats = new;
9256 state->dts_formats[ndx] = fmt;
9257
9258 return (ndx + 1);
9259 }
9260
9261 static void
9262 dtrace_format_remove(dtrace_state_t *state, uint16_t format)
9263 {
9264 char *fmt;
9265
9266 ASSERT(state->dts_formats != NULL);
9267 ASSERT(format <= state->dts_nformats);
9268 ASSERT(state->dts_formats[format - 1] != NULL);
9269
9270 fmt = state->dts_formats[format - 1];
9271 kmem_free(fmt, strlen(fmt) + 1);
9272 state->dts_formats[format - 1] = NULL;
9273 }
9274
9275 static void
9276 dtrace_format_destroy(dtrace_state_t *state)
9277 {
9278 int i;
9279
9280 if (state->dts_nformats == 0) {
9281 ASSERT(state->dts_formats == NULL);
9282 return;
9283 }
9284
9285 ASSERT(state->dts_formats != NULL);
9286
9287 for (i = 0; i < state->dts_nformats; i++) {
9288 char *fmt = state->dts_formats[i];
9289
9290 if (fmt == NULL)
9291 continue;
9292
9293 kmem_free(fmt, strlen(fmt) + 1);
9294 }
9295
9296 kmem_free(state->dts_formats, state->dts_nformats * sizeof (char *));
9297 state->dts_nformats = 0;
9298 state->dts_formats = NULL;
9299 }
9300
9301 /*
9302 * DTrace Predicate Functions
9303 */
9304 static dtrace_predicate_t *
9305 dtrace_predicate_create(dtrace_difo_t *dp)
9306 {
9307 dtrace_predicate_t *pred;
9308
9309 ASSERT(MUTEX_HELD(&dtrace_lock));
9310 ASSERT(dp->dtdo_refcnt != 0);
9311
9312 pred = kmem_zalloc(sizeof (dtrace_predicate_t), KM_SLEEP);
9313 pred->dtp_difo = dp;
9314 pred->dtp_refcnt = 1;
9315
9316 if (!dtrace_difo_cacheable(dp))
9317 return (pred);
9318
9319 if (dtrace_predcache_id == DTRACE_CACHEIDNONE) {
9320 /*
9321 * This is only theoretically possible -- we have had 2^32
9322 * cacheable predicates on this machine. We cannot allow any
9323 * more predicates to become cacheable: as unlikely as it is,
9324 * there may be a thread caching a (now stale) predicate cache
9325 * ID. (N.B.: the temptation is being successfully resisted to
9326 * have this cmn_err() "Holy shit -- we executed this code!")
9327 */
9328 return (pred);
9329 }
9330
9331 pred->dtp_cacheid = dtrace_predcache_id++;
9332
9333 return (pred);
9334 }
9335
9336 static void
9337 dtrace_predicate_hold(dtrace_predicate_t *pred)
9338 {
9339 ASSERT(MUTEX_HELD(&dtrace_lock));
9340 ASSERT(pred->dtp_difo != NULL && pred->dtp_difo->dtdo_refcnt != 0);
9341 ASSERT(pred->dtp_refcnt > 0);
9342
9343 pred->dtp_refcnt++;
9344 }
9345
9346 static void
9347 dtrace_predicate_release(dtrace_predicate_t *pred, dtrace_vstate_t *vstate)
9348 {
9349 dtrace_difo_t *dp = pred->dtp_difo;
9350
9351 ASSERT(MUTEX_HELD(&dtrace_lock));
9352 ASSERT(dp != NULL && dp->dtdo_refcnt != 0);
9353 ASSERT(pred->dtp_refcnt > 0);
9354
9355 if (--pred->dtp_refcnt == 0) {
9356 dtrace_difo_release(pred->dtp_difo, vstate);
9357 kmem_free(pred, sizeof (dtrace_predicate_t));
9358 }
9359 }
9360
9361 /*
9362 * DTrace Action Description Functions
9363 */
9364 static dtrace_actdesc_t *
9365 dtrace_actdesc_create(dtrace_actkind_t kind, uint32_t ntuple,
9366 uint64_t uarg, uint64_t arg)
9367 {
9368 dtrace_actdesc_t *act;
9369
9370 ASSERT(!DTRACEACT_ISPRINTFLIKE(kind) || (arg != NULL &&
9371 arg >= KERNELBASE) || (arg == NULL && kind == DTRACEACT_PRINTA));
9372
9373 act = kmem_zalloc(sizeof (dtrace_actdesc_t), KM_SLEEP);
9374 act->dtad_kind = kind;
9375 act->dtad_ntuple = ntuple;
9376 act->dtad_uarg = uarg;
9377 act->dtad_arg = arg;
9378 act->dtad_refcnt = 1;
9379
9380 return (act);
9381 }
9382
9383 static void
9384 dtrace_actdesc_hold(dtrace_actdesc_t *act)
9385 {
9386 ASSERT(act->dtad_refcnt >= 1);
9387 act->dtad_refcnt++;
9388 }
9389
9390 static void
9391 dtrace_actdesc_release(dtrace_actdesc_t *act, dtrace_vstate_t *vstate)
9392 {
9393 dtrace_actkind_t kind = act->dtad_kind;
9394 dtrace_difo_t *dp;
9395
9396 ASSERT(act->dtad_refcnt >= 1);
9397
9398 if (--act->dtad_refcnt != 0)
9399 return;
9400
9401 if ((dp = act->dtad_difo) != NULL)
9402 dtrace_difo_release(dp, vstate);
9403
9404 if (DTRACEACT_ISPRINTFLIKE(kind)) {
9405 char *str = (char *)(uintptr_t)act->dtad_arg;
9406
9407 ASSERT((str != NULL && (uintptr_t)str >= KERNELBASE) ||
9408 (str == NULL && act->dtad_kind == DTRACEACT_PRINTA));
9409
9410 if (str != NULL)
9411 kmem_free(str, strlen(str) + 1);
9412 }
9413
9414 kmem_free(act, sizeof (dtrace_actdesc_t));
9415 }
9416
9417 /*
9418 * DTrace ECB Functions
9419 */
9420 static dtrace_ecb_t *
9421 dtrace_ecb_add(dtrace_state_t *state, dtrace_probe_t *probe)
9422 {
9423 dtrace_ecb_t *ecb;
9424 dtrace_epid_t epid;
9425
9426 ASSERT(MUTEX_HELD(&dtrace_lock));
9427
9428 ecb = kmem_zalloc(sizeof (dtrace_ecb_t), KM_SLEEP);
9429 ecb->dte_predicate = NULL;
9430 ecb->dte_probe = probe;
9431
9432 /*
9433 * The default size is the size of the default action: recording
9434 * the header.
9435 */
9436 ecb->dte_size = ecb->dte_needed = sizeof (dtrace_rechdr_t);
9437 ecb->dte_alignment = sizeof (dtrace_epid_t);
9438
9439 epid = state->dts_epid++;
9440
9441 if (epid - 1 >= state->dts_necbs) {
9442 dtrace_ecb_t **oecbs = state->dts_ecbs, **ecbs;
9443 int necbs = state->dts_necbs << 1;
9444
9445 ASSERT(epid == state->dts_necbs + 1);
9446
9447 if (necbs == 0) {
9448 ASSERT(oecbs == NULL);
9449 necbs = 1;
9450 }
9451
9452 ecbs = kmem_zalloc(necbs * sizeof (*ecbs), KM_SLEEP);
9453
9454 if (oecbs != NULL)
9455 bcopy(oecbs, ecbs, state->dts_necbs * sizeof (*ecbs));
9456
9457 dtrace_membar_producer();
9458 state->dts_ecbs = ecbs;
9459
9460 if (oecbs != NULL) {
9461 /*
9462 * If this state is active, we must dtrace_sync()
9463 * before we can free the old dts_ecbs array: we're
9464 * coming in hot, and there may be active ring
9465 * buffer processing (which indexes into the dts_ecbs
9466 * array) on another CPU.
9467 */
9468 if (state->dts_activity != DTRACE_ACTIVITY_INACTIVE)
9469 dtrace_sync();
9470
9471 kmem_free(oecbs, state->dts_necbs * sizeof (*ecbs));
9472 }
9473
9474 dtrace_membar_producer();
9475 state->dts_necbs = necbs;
9476 }
9477
9478 ecb->dte_state = state;
9479
9480 ASSERT(state->dts_ecbs[epid - 1] == NULL);
9481 dtrace_membar_producer();
9482 state->dts_ecbs[(ecb->dte_epid = epid) - 1] = ecb;
9483
9484 return (ecb);
9485 }
9486
9487 static int
9488 dtrace_ecb_enable(dtrace_ecb_t *ecb)
9489 {
9490 dtrace_probe_t *probe = ecb->dte_probe;
9491
9492 ASSERT(MUTEX_HELD(&cpu_lock));
9493 ASSERT(MUTEX_HELD(&dtrace_lock));
9494 ASSERT(ecb->dte_next == NULL);
9495
9496 if (probe == NULL) {
9497 /*
9498 * This is the NULL probe -- there's nothing to do.
9499 */
9500 return (0);
9501 }
9502
9503 if (probe->dtpr_ecb == NULL) {
9504 dtrace_provider_t *prov = probe->dtpr_provider;
9505
9506 /*
9507 * We're the first ECB on this probe.
9508 */
9509 probe->dtpr_ecb = probe->dtpr_ecb_last = ecb;
9510
9511 if (ecb->dte_predicate != NULL)
9512 probe->dtpr_predcache = ecb->dte_predicate->dtp_cacheid;
9513
9514 return (prov->dtpv_pops.dtps_enable(prov->dtpv_arg,
9515 probe->dtpr_id, probe->dtpr_arg));
9516 } else {
9517 /*
9518 * This probe is already active. Swing the last pointer to
9519 * point to the new ECB, and issue a dtrace_sync() to assure
9520 * that all CPUs have seen the change.
9521 */
9522 ASSERT(probe->dtpr_ecb_last != NULL);
9523 probe->dtpr_ecb_last->dte_next = ecb;
9524 probe->dtpr_ecb_last = ecb;
9525 probe->dtpr_predcache = 0;
9526
9527 dtrace_sync();
9528 return (0);
9529 }
9530 }
9531
9532 static void
9533 dtrace_ecb_resize(dtrace_ecb_t *ecb)
9534 {
9535 dtrace_action_t *act;
9536 uint32_t curneeded = UINT32_MAX;
9537 uint32_t aggbase = UINT32_MAX;
9538
9539 /*
9540 * If we record anything, we always record the dtrace_rechdr_t. (And
9541 * we always record it first.)
9542 */
9543 ecb->dte_size = sizeof (dtrace_rechdr_t);
9544 ecb->dte_alignment = sizeof (dtrace_epid_t);
9545
9546 for (act = ecb->dte_action; act != NULL; act = act->dta_next) {
9547 dtrace_recdesc_t *rec = &act->dta_rec;
9548 ASSERT(rec->dtrd_size > 0 || rec->dtrd_alignment == 1);
9549
9550 ecb->dte_alignment = MAX(ecb->dte_alignment,
9551 rec->dtrd_alignment);
9552
9553 if (DTRACEACT_ISAGG(act->dta_kind)) {
9554 dtrace_aggregation_t *agg = (dtrace_aggregation_t *)act;
9555
9556 ASSERT(rec->dtrd_size != 0);
9557 ASSERT(agg->dtag_first != NULL);
9558 ASSERT(act->dta_prev->dta_intuple);
9559 ASSERT(aggbase != UINT32_MAX);
9560 ASSERT(curneeded != UINT32_MAX);
9561
9562 agg->dtag_base = aggbase;
9563
9564 curneeded = P2ROUNDUP(curneeded, rec->dtrd_alignment);
9565 rec->dtrd_offset = curneeded;
9566 curneeded += rec->dtrd_size;
9567 ecb->dte_needed = MAX(ecb->dte_needed, curneeded);
9568
9569 aggbase = UINT32_MAX;
9570 curneeded = UINT32_MAX;
9571 } else if (act->dta_intuple) {
9572 if (curneeded == UINT32_MAX) {
9573 /*
9574 * This is the first record in a tuple. Align
9575 * curneeded to be at offset 4 in an 8-byte
9576 * aligned block.
9577 */
9578 ASSERT(act->dta_prev == NULL ||
9579 !act->dta_prev->dta_intuple);
9580 ASSERT3U(aggbase, ==, UINT32_MAX);
9581 curneeded = P2PHASEUP(ecb->dte_size,
9582 sizeof (uint64_t), sizeof (dtrace_aggid_t));
9583
9584 aggbase = curneeded - sizeof (dtrace_aggid_t);
9585 ASSERT(IS_P2ALIGNED(aggbase,
9586 sizeof (uint64_t)));
9587 }
9588 curneeded = P2ROUNDUP(curneeded, rec->dtrd_alignment);
9589 rec->dtrd_offset = curneeded;
9590 curneeded += rec->dtrd_size;
9591 } else {
9592 /* tuples must be followed by an aggregation */
9593 ASSERT(act->dta_prev == NULL ||
9594 !act->dta_prev->dta_intuple);
9595
9596 ecb->dte_size = P2ROUNDUP(ecb->dte_size,
9597 rec->dtrd_alignment);
9598 rec->dtrd_offset = ecb->dte_size;
9599 ecb->dte_size += rec->dtrd_size;
9600 ecb->dte_needed = MAX(ecb->dte_needed, ecb->dte_size);
9601 }
9602 }
9603
9604 if ((act = ecb->dte_action) != NULL &&
9605 !(act->dta_kind == DTRACEACT_SPECULATE && act->dta_next == NULL) &&
9606 ecb->dte_size == sizeof (dtrace_rechdr_t)) {
9607 /*
9608 * If the size is still sizeof (dtrace_rechdr_t), then all
9609 * actions store no data; set the size to 0.
9610 */
9611 ecb->dte_size = 0;
9612 }
9613
9614 ecb->dte_size = P2ROUNDUP(ecb->dte_size, sizeof (dtrace_epid_t));
9615 ecb->dte_needed = P2ROUNDUP(ecb->dte_needed, (sizeof (dtrace_epid_t)));
9616 ecb->dte_state->dts_needed = MAX(ecb->dte_state->dts_needed,
9617 ecb->dte_needed);
9618 }
9619
9620 static dtrace_action_t *
9621 dtrace_ecb_aggregation_create(dtrace_ecb_t *ecb, dtrace_actdesc_t *desc)
9622 {
9623 dtrace_aggregation_t *agg;
9624 size_t size = sizeof (uint64_t);
9625 int ntuple = desc->dtad_ntuple;
9626 dtrace_action_t *act;
9627 dtrace_recdesc_t *frec;
9628 dtrace_aggid_t aggid;
9629 dtrace_state_t *state = ecb->dte_state;
9630
9631 agg = kmem_zalloc(sizeof (dtrace_aggregation_t), KM_SLEEP);
9632 agg->dtag_ecb = ecb;
9633
9634 ASSERT(DTRACEACT_ISAGG(desc->dtad_kind));
9635
9636 switch (desc->dtad_kind) {
9637 case DTRACEAGG_MIN:
9638 agg->dtag_initial = INT64_MAX;
9639 agg->dtag_aggregate = dtrace_aggregate_min;
9640 break;
9641
9642 case DTRACEAGG_MAX:
9643 agg->dtag_initial = INT64_MIN;
9644 agg->dtag_aggregate = dtrace_aggregate_max;
9645 break;
9646
9647 case DTRACEAGG_COUNT:
9648 agg->dtag_aggregate = dtrace_aggregate_count;
9649 break;
9650
9651 case DTRACEAGG_QUANTIZE:
9652 agg->dtag_aggregate = dtrace_aggregate_quantize;
9653 size = (((sizeof (uint64_t) * NBBY) - 1) * 2 + 1) *
9654 sizeof (uint64_t);
9655 break;
9656
9657 case DTRACEAGG_LQUANTIZE: {
9658 uint16_t step = DTRACE_LQUANTIZE_STEP(desc->dtad_arg);
9659 uint16_t levels = DTRACE_LQUANTIZE_LEVELS(desc->dtad_arg);
9660
9661 agg->dtag_initial = desc->dtad_arg;
9662 agg->dtag_aggregate = dtrace_aggregate_lquantize;
9663
9664 if (step == 0 || levels == 0)
9665 goto err;
9666
9667 size = levels * sizeof (uint64_t) + 3 * sizeof (uint64_t);
9668 break;
9669 }
9670
9671 case DTRACEAGG_LLQUANTIZE: {
9672 uint16_t factor = DTRACE_LLQUANTIZE_FACTOR(desc->dtad_arg);
9673 uint16_t low = DTRACE_LLQUANTIZE_LOW(desc->dtad_arg);
9674 uint16_t high = DTRACE_LLQUANTIZE_HIGH(desc->dtad_arg);
9675 uint16_t nsteps = DTRACE_LLQUANTIZE_NSTEP(desc->dtad_arg);
9676 int64_t v;
9677
9678 agg->dtag_initial = desc->dtad_arg;
9679 agg->dtag_aggregate = dtrace_aggregate_llquantize;
9680
9681 if (factor < 2 || low >= high || nsteps < factor)
9682 goto err;
9683
9684 /*
9685 * Now check that the number of steps evenly divides a power
9686 * of the factor. (This assures both integer bucket size and
9687 * linearity within each magnitude.)
9688 */
9689 for (v = factor; v < nsteps; v *= factor)
9690 continue;
9691
9692 if ((v % nsteps) || (nsteps % factor))
9693 goto err;
9694
9695 size = (dtrace_aggregate_llquantize_bucket(factor,
9696 low, high, nsteps, INT64_MAX) + 2) * sizeof (uint64_t);
9697 break;
9698 }
9699
9700 case DTRACEAGG_AVG:
9701 agg->dtag_aggregate = dtrace_aggregate_avg;
9702 size = sizeof (uint64_t) * 2;
9703 break;
9704
9705 case DTRACEAGG_STDDEV:
9706 agg->dtag_aggregate = dtrace_aggregate_stddev;
9707 size = sizeof (uint64_t) * 4;
9708 break;
9709
9710 case DTRACEAGG_SUM:
9711 agg->dtag_aggregate = dtrace_aggregate_sum;
9712 break;
9713
9714 default:
9715 goto err;
9716 }
9717
9718 agg->dtag_action.dta_rec.dtrd_size = size;
9719
9720 if (ntuple == 0)
9721 goto err;
9722
9723 /*
9724 * We must make sure that we have enough actions for the n-tuple.
9725 */
9726 for (act = ecb->dte_action_last; act != NULL; act = act->dta_prev) {
9727 if (DTRACEACT_ISAGG(act->dta_kind))
9728 break;
9729
9730 if (--ntuple == 0) {
9731 /*
9732 * This is the action with which our n-tuple begins.
9733 */
9734 agg->dtag_first = act;
9735 goto success;
9736 }
9737 }
9738
9739 /*
9740 * This n-tuple is short by ntuple elements. Return failure.
9741 */
9742 ASSERT(ntuple != 0);
9743 err:
9744 kmem_free(agg, sizeof (dtrace_aggregation_t));
9745 return (NULL);
9746
9747 success:
9748 /*
9749 * If the last action in the tuple has a size of zero, it's actually
9750 * an expression argument for the aggregating action.
9751 */
9752 ASSERT(ecb->dte_action_last != NULL);
9753 act = ecb->dte_action_last;
9754
9755 if (act->dta_kind == DTRACEACT_DIFEXPR) {
9756 ASSERT(act->dta_difo != NULL);
9757
9758 if (act->dta_difo->dtdo_rtype.dtdt_size == 0)
9759 agg->dtag_hasarg = 1;
9760 }
9761
9762 /*
9763 * We need to allocate an id for this aggregation.
9764 */
9765 aggid = (dtrace_aggid_t)(uintptr_t)vmem_alloc(state->dts_aggid_arena, 1,
9766 VM_BESTFIT | VM_SLEEP);
9767
9768 if (aggid - 1 >= state->dts_naggregations) {
9769 dtrace_aggregation_t **oaggs = state->dts_aggregations;
9770 dtrace_aggregation_t **aggs;
9771 int naggs = state->dts_naggregations << 1;
9772 int onaggs = state->dts_naggregations;
9773
9774 ASSERT(aggid == state->dts_naggregations + 1);
9775
9776 if (naggs == 0) {
9777 ASSERT(oaggs == NULL);
9778 naggs = 1;
9779 }
9780
9781 aggs = kmem_zalloc(naggs * sizeof (*aggs), KM_SLEEP);
9782
9783 if (oaggs != NULL) {
9784 bcopy(oaggs, aggs, onaggs * sizeof (*aggs));
9785 kmem_free(oaggs, onaggs * sizeof (*aggs));
9786 }
9787
9788 state->dts_aggregations = aggs;
9789 state->dts_naggregations = naggs;
9790 }
9791
9792 ASSERT(state->dts_aggregations[aggid - 1] == NULL);
9793 state->dts_aggregations[(agg->dtag_id = aggid) - 1] = agg;
9794
9795 frec = &agg->dtag_first->dta_rec;
9796 if (frec->dtrd_alignment < sizeof (dtrace_aggid_t))
9797 frec->dtrd_alignment = sizeof (dtrace_aggid_t);
9798
9799 for (act = agg->dtag_first; act != NULL; act = act->dta_next) {
9800 ASSERT(!act->dta_intuple);
9801 act->dta_intuple = 1;
9802 }
9803
9804 return (&agg->dtag_action);
9805 }
9806
9807 static void
9808 dtrace_ecb_aggregation_destroy(dtrace_ecb_t *ecb, dtrace_action_t *act)
9809 {
9810 dtrace_aggregation_t *agg = (dtrace_aggregation_t *)act;
9811 dtrace_state_t *state = ecb->dte_state;
9812 dtrace_aggid_t aggid = agg->dtag_id;
9813
9814 ASSERT(DTRACEACT_ISAGG(act->dta_kind));
9815 vmem_free(state->dts_aggid_arena, (void *)(uintptr_t)aggid, 1);
9816
9817 ASSERT(state->dts_aggregations[aggid - 1] == agg);
9818 state->dts_aggregations[aggid - 1] = NULL;
9819
9820 kmem_free(agg, sizeof (dtrace_aggregation_t));
9821 }
9822
9823 static int
9824 dtrace_ecb_action_add(dtrace_ecb_t *ecb, dtrace_actdesc_t *desc)
9825 {
9826 dtrace_action_t *action, *last;
9827 dtrace_difo_t *dp = desc->dtad_difo;
9828 uint32_t size = 0, align = sizeof (uint8_t), mask;
9829 uint16_t format = 0;
9830 dtrace_recdesc_t *rec;
9831 dtrace_state_t *state = ecb->dte_state;
9832 dtrace_optval_t *opt = state->dts_options, nframes, strsize;
9833 uint64_t arg = desc->dtad_arg;
9834
9835 ASSERT(MUTEX_HELD(&dtrace_lock));
9836 ASSERT(ecb->dte_action == NULL || ecb->dte_action->dta_refcnt == 1);
9837
9838 if (DTRACEACT_ISAGG(desc->dtad_kind)) {
9839 /*
9840 * If this is an aggregating action, there must be neither
9841 * a speculate nor a commit on the action chain.
9842 */
9843 dtrace_action_t *act;
9844
9845 for (act = ecb->dte_action; act != NULL; act = act->dta_next) {
9846 if (act->dta_kind == DTRACEACT_COMMIT)
9847 return (EINVAL);
9848
9849 if (act->dta_kind == DTRACEACT_SPECULATE)
9850 return (EINVAL);
9851 }
9852
9853 action = dtrace_ecb_aggregation_create(ecb, desc);
9854
9855 if (action == NULL)
9856 return (EINVAL);
9857 } else {
9858 if (DTRACEACT_ISDESTRUCTIVE(desc->dtad_kind) ||
9859 (desc->dtad_kind == DTRACEACT_DIFEXPR &&
9860 dp != NULL && dp->dtdo_destructive)) {
9861 state->dts_destructive = 1;
9862 }
9863
9864 switch (desc->dtad_kind) {
9865 case DTRACEACT_PRINTF:
9866 case DTRACEACT_PRINTA:
9867 case DTRACEACT_SYSTEM:
9868 case DTRACEACT_FREOPEN:
9869 case DTRACEACT_DIFEXPR:
9870 /*
9871 * We know that our arg is a string -- turn it into a
9872 * format.
9873 */
9874 if (arg == NULL) {
9875 ASSERT(desc->dtad_kind == DTRACEACT_PRINTA ||
9876 desc->dtad_kind == DTRACEACT_DIFEXPR);
9877 format = 0;
9878 } else {
9879 ASSERT(arg != NULL);
9880 ASSERT(arg > KERNELBASE);
9881 format = dtrace_format_add(state,
9882 (char *)(uintptr_t)arg);
9883 }
9884
9885 /*FALLTHROUGH*/
9886 case DTRACEACT_LIBACT:
9887 case DTRACEACT_TRACEMEM:
9888 case DTRACEACT_TRACEMEM_DYNSIZE:
9889 if (dp == NULL)
9890 return (EINVAL);
9891
9892 if ((size = dp->dtdo_rtype.dtdt_size) != 0)
9893 break;
9894
9895 if (dp->dtdo_rtype.dtdt_kind == DIF_TYPE_STRING) {
9896 if (!(dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF))
9897 return (EINVAL);
9898
9899 size = opt[DTRACEOPT_STRSIZE];
9900 }
9901
9902 break;
9903
9904 case DTRACEACT_STACK:
9905 if ((nframes = arg) == 0) {
9906 nframes = opt[DTRACEOPT_STACKFRAMES];
9907 ASSERT(nframes > 0);
9908 arg = nframes;
9909 }
9910
9911 size = nframes * sizeof (pc_t);
9912 break;
9913
9914 case DTRACEACT_JSTACK:
9915 if ((strsize = DTRACE_USTACK_STRSIZE(arg)) == 0)
9916 strsize = opt[DTRACEOPT_JSTACKSTRSIZE];
9917
9918 if ((nframes = DTRACE_USTACK_NFRAMES(arg)) == 0)
9919 nframes = opt[DTRACEOPT_JSTACKFRAMES];
9920
9921 arg = DTRACE_USTACK_ARG(nframes, strsize);
9922
9923 /*FALLTHROUGH*/
9924 case DTRACEACT_USTACK:
9925 if (desc->dtad_kind != DTRACEACT_JSTACK &&
9926 (nframes = DTRACE_USTACK_NFRAMES(arg)) == 0) {
9927 strsize = DTRACE_USTACK_STRSIZE(arg);
9928 nframes = opt[DTRACEOPT_USTACKFRAMES];
9929 ASSERT(nframes > 0);
9930 arg = DTRACE_USTACK_ARG(nframes, strsize);
9931 }
9932
9933 /*
9934 * Save a slot for the pid.
9935 */
9936 size = (nframes + 1) * sizeof (uint64_t);
9937 size += DTRACE_USTACK_STRSIZE(arg);
9938 size = P2ROUNDUP(size, (uint32_t)(sizeof (uintptr_t)));
9939
9940 break;
9941
9942 case DTRACEACT_SYM:
9943 case DTRACEACT_MOD:
9944 if (dp == NULL || ((size = dp->dtdo_rtype.dtdt_size) !=
9945 sizeof (uint64_t)) ||
9946 (dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF))
9947 return (EINVAL);
9948 break;
9949
9950 case DTRACEACT_USYM:
9951 case DTRACEACT_UMOD:
9952 case DTRACEACT_UADDR:
9953 if (dp == NULL ||
9954 (dp->dtdo_rtype.dtdt_size != sizeof (uint64_t)) ||
9955 (dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF))
9956 return (EINVAL);
9957
9958 /*
9959 * We have a slot for the pid, plus a slot for the
9960 * argument. To keep things simple (aligned with
9961 * bitness-neutral sizing), we store each as a 64-bit
9962 * quantity.
9963 */
9964 size = 2 * sizeof (uint64_t);
9965 break;
9966
9967 case DTRACEACT_STOP:
9968 case DTRACEACT_BREAKPOINT:
9969 case DTRACEACT_PANIC:
9970 break;
9971
9972 case DTRACEACT_CHILL:
9973 case DTRACEACT_DISCARD:
9974 case DTRACEACT_RAISE:
9975 if (dp == NULL)
9976 return (EINVAL);
9977 break;
9978
9979 case DTRACEACT_EXIT:
9980 if (dp == NULL ||
9981 (size = dp->dtdo_rtype.dtdt_size) != sizeof (int) ||
9982 (dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF))
9983 return (EINVAL);
9984 break;
9985
9986 case DTRACEACT_SPECULATE:
9987 if (ecb->dte_size > sizeof (dtrace_rechdr_t))
9988 return (EINVAL);
9989
9990 if (dp == NULL)
9991 return (EINVAL);
9992
9993 state->dts_speculates = 1;
9994 break;
9995
9996 case DTRACEACT_COMMIT: {
9997 dtrace_action_t *act = ecb->dte_action;
9998
9999 for (; act != NULL; act = act->dta_next) {
10000 if (act->dta_kind == DTRACEACT_COMMIT)
10001 return (EINVAL);
10002 }
10003
10004 if (dp == NULL)
10005 return (EINVAL);
10006 break;
10007 }
10008
10009 default:
10010 return (EINVAL);
10011 }
10012
10013 if (size != 0 || desc->dtad_kind == DTRACEACT_SPECULATE) {
10014 /*
10015 * If this is a data-storing action or a speculate,
10016 * we must be sure that there isn't a commit on the
10017 * action chain.
10018 */
10019 dtrace_action_t *act = ecb->dte_action;
10020
10021 for (; act != NULL; act = act->dta_next) {
10022 if (act->dta_kind == DTRACEACT_COMMIT)
10023 return (EINVAL);
10024 }
10025 }
10026
10027 action = kmem_zalloc(sizeof (dtrace_action_t), KM_SLEEP);
10028 action->dta_rec.dtrd_size = size;
10029 }
10030
10031 action->dta_refcnt = 1;
10032 rec = &action->dta_rec;
10033 size = rec->dtrd_size;
10034
10035 for (mask = sizeof (uint64_t) - 1; size != 0 && mask > 0; mask >>= 1) {
10036 if (!(size & mask)) {
10037 align = mask + 1;
10038 break;
10039 }
10040 }
10041
10042 action->dta_kind = desc->dtad_kind;
10043
10044 if ((action->dta_difo = dp) != NULL)
10045 dtrace_difo_hold(dp);
10046
10047 rec->dtrd_action = action->dta_kind;
10048 rec->dtrd_arg = arg;
10049 rec->dtrd_uarg = desc->dtad_uarg;
10050 rec->dtrd_alignment = (uint16_t)align;
10051 rec->dtrd_format = format;
10052
10053 if ((last = ecb->dte_action_last) != NULL) {
10054 ASSERT(ecb->dte_action != NULL);
10055 action->dta_prev = last;
10056 last->dta_next = action;
10057 } else {
10058 ASSERT(ecb->dte_action == NULL);
10059 ecb->dte_action = action;
10060 }
10061
10062 ecb->dte_action_last = action;
10063
10064 return (0);
10065 }
10066
10067 static void
10068 dtrace_ecb_action_remove(dtrace_ecb_t *ecb)
10069 {
10070 dtrace_action_t *act = ecb->dte_action, *next;
10071 dtrace_vstate_t *vstate = &ecb->dte_state->dts_vstate;
10072 dtrace_difo_t *dp;
10073 uint16_t format;
10074
10075 if (act != NULL && act->dta_refcnt > 1) {
10076 ASSERT(act->dta_next == NULL || act->dta_next->dta_refcnt == 1);
10077 act->dta_refcnt--;
10078 } else {
10079 for (; act != NULL; act = next) {
10080 next = act->dta_next;
10081 ASSERT(next != NULL || act == ecb->dte_action_last);
10082 ASSERT(act->dta_refcnt == 1);
10083
10084 if ((format = act->dta_rec.dtrd_format) != 0)
10085 dtrace_format_remove(ecb->dte_state, format);
10086
10087 if ((dp = act->dta_difo) != NULL)
10088 dtrace_difo_release(dp, vstate);
10089
10090 if (DTRACEACT_ISAGG(act->dta_kind)) {
10091 dtrace_ecb_aggregation_destroy(ecb, act);
10092 } else {
10093 kmem_free(act, sizeof (dtrace_action_t));
10094 }
10095 }
10096 }
10097
10098 ecb->dte_action = NULL;
10099 ecb->dte_action_last = NULL;
10100 ecb->dte_size = 0;
10101 }
10102
10103 static void
10104 dtrace_ecb_disable(dtrace_ecb_t *ecb)
10105 {
10106 /*
10107 * We disable the ECB by removing it from its probe.
10108 */
10109 dtrace_ecb_t *pecb, *prev = NULL;
10110 dtrace_probe_t *probe = ecb->dte_probe;
10111
10112 ASSERT(MUTEX_HELD(&dtrace_lock));
10113
10114 if (probe == NULL) {
10115 /*
10116 * This is the NULL probe; there is nothing to disable.
10117 */
10118 return;
10119 }
10120
10121 for (pecb = probe->dtpr_ecb; pecb != NULL; pecb = pecb->dte_next) {
10122 if (pecb == ecb)
10123 break;
10124 prev = pecb;
10125 }
10126
10127 ASSERT(pecb != NULL);
10128
10129 if (prev == NULL) {
10130 probe->dtpr_ecb = ecb->dte_next;
10131 } else {
10132 prev->dte_next = ecb->dte_next;
10133 }
10134
10135 if (ecb == probe->dtpr_ecb_last) {
10136 ASSERT(ecb->dte_next == NULL);
10137 probe->dtpr_ecb_last = prev;
10138 }
10139
10140 /*
10141 * The ECB has been disconnected from the probe; now sync to assure
10142 * that all CPUs have seen the change before returning.
10143 */
10144 dtrace_sync();
10145
10146 if (probe->dtpr_ecb == NULL) {
10147 /*
10148 * That was the last ECB on the probe; clear the predicate
10149 * cache ID for the probe, disable it and sync one more time
10150 * to assure that we'll never hit it again.
10151 */
10152 dtrace_provider_t *prov = probe->dtpr_provider;
10153
10154 ASSERT(ecb->dte_next == NULL);
10155 ASSERT(probe->dtpr_ecb_last == NULL);
10156 probe->dtpr_predcache = DTRACE_CACHEIDNONE;
10157 prov->dtpv_pops.dtps_disable(prov->dtpv_arg,
10158 probe->dtpr_id, probe->dtpr_arg);
10159 dtrace_sync();
10160 } else {
10161 /*
10162 * There is at least one ECB remaining on the probe. If there
10163 * is _exactly_ one, set the probe's predicate cache ID to be
10164 * the predicate cache ID of the remaining ECB.
10165 */
10166 ASSERT(probe->dtpr_ecb_last != NULL);
10167 ASSERT(probe->dtpr_predcache == DTRACE_CACHEIDNONE);
10168
10169 if (probe->dtpr_ecb == probe->dtpr_ecb_last) {
10170 dtrace_predicate_t *p = probe->dtpr_ecb->dte_predicate;
10171
10172 ASSERT(probe->dtpr_ecb->dte_next == NULL);
10173
10174 if (p != NULL)
10175 probe->dtpr_predcache = p->dtp_cacheid;
10176 }
10177
10178 ecb->dte_next = NULL;
10179 }
10180 }
10181
10182 static void
10183 dtrace_ecb_destroy(dtrace_ecb_t *ecb)
10184 {
10185 dtrace_state_t *state = ecb->dte_state;
10186 dtrace_vstate_t *vstate = &state->dts_vstate;
10187 dtrace_predicate_t *pred;
10188 dtrace_epid_t epid = ecb->dte_epid;
10189
10190 ASSERT(MUTEX_HELD(&dtrace_lock));
10191 ASSERT(ecb->dte_next == NULL);
10192 ASSERT(ecb->dte_probe == NULL || ecb->dte_probe->dtpr_ecb != ecb);
10193
10194 if ((pred = ecb->dte_predicate) != NULL)
10195 dtrace_predicate_release(pred, vstate);
10196
10197 dtrace_ecb_action_remove(ecb);
10198
10199 ASSERT(state->dts_ecbs[epid - 1] == ecb);
10200 state->dts_ecbs[epid - 1] = NULL;
10201
10202 kmem_free(ecb, sizeof (dtrace_ecb_t));
10203 }
10204
10205 static dtrace_ecb_t *
10206 dtrace_ecb_create(dtrace_state_t *state, dtrace_probe_t *probe,
10207 dtrace_enabling_t *enab)
10208 {
10209 dtrace_ecb_t *ecb;
10210 dtrace_predicate_t *pred;
10211 dtrace_actdesc_t *act;
10212 dtrace_provider_t *prov;
10213 dtrace_ecbdesc_t *desc = enab->dten_current;
10214
10215 ASSERT(MUTEX_HELD(&dtrace_lock));
10216 ASSERT(state != NULL);
10217
10218 ecb = dtrace_ecb_add(state, probe);
10219 ecb->dte_uarg = desc->dted_uarg;
10220
10221 if ((pred = desc->dted_pred.dtpdd_predicate) != NULL) {
10222 dtrace_predicate_hold(pred);
10223 ecb->dte_predicate = pred;
10224 }
10225
10226 if (probe != NULL) {
10227 /*
10228 * If the provider shows more leg than the consumer is old
10229 * enough to see, we need to enable the appropriate implicit
10230 * predicate bits to prevent the ecb from activating at
10231 * revealing times.
10232 *
10233 * Providers specifying DTRACE_PRIV_USER at register time
10234 * are stating that they need the /proc-style privilege
10235 * model to be enforced, and this is what DTRACE_COND_OWNER
10236 * and DTRACE_COND_ZONEOWNER will then do at probe time.
10237 */
10238 prov = probe->dtpr_provider;
10239 if (!(state->dts_cred.dcr_visible & DTRACE_CRV_ALLPROC) &&
10240 (prov->dtpv_priv.dtpp_flags & DTRACE_PRIV_USER))
10241 ecb->dte_cond |= DTRACE_COND_OWNER;
10242
10243 if (!(state->dts_cred.dcr_visible & DTRACE_CRV_ALLZONE) &&
10244 (prov->dtpv_priv.dtpp_flags & DTRACE_PRIV_USER))
10245 ecb->dte_cond |= DTRACE_COND_ZONEOWNER;
10246
10247 /*
10248 * If the provider shows us kernel innards and the user
10249 * is lacking sufficient privilege, enable the
10250 * DTRACE_COND_USERMODE implicit predicate.
10251 */
10252 if (!(state->dts_cred.dcr_visible & DTRACE_CRV_KERNEL) &&
10253 (prov->dtpv_priv.dtpp_flags & DTRACE_PRIV_KERNEL))
10254 ecb->dte_cond |= DTRACE_COND_USERMODE;
10255 }
10256
10257 if (dtrace_ecb_create_cache != NULL) {
10258 /*
10259 * If we have a cached ecb, we'll use its action list instead
10260 * of creating our own (saving both time and space).
10261 */
10262 dtrace_ecb_t *cached = dtrace_ecb_create_cache;
10263 dtrace_action_t *act = cached->dte_action;
10264
10265 if (act != NULL) {
10266 ASSERT(act->dta_refcnt > 0);
10267 act->dta_refcnt++;
10268 ecb->dte_action = act;
10269 ecb->dte_action_last = cached->dte_action_last;
10270 ecb->dte_needed = cached->dte_needed;
10271 ecb->dte_size = cached->dte_size;
10272 ecb->dte_alignment = cached->dte_alignment;
10273 }
10274
10275 return (ecb);
10276 }
10277
10278 for (act = desc->dted_action; act != NULL; act = act->dtad_next) {
10279 if ((enab->dten_error = dtrace_ecb_action_add(ecb, act)) != 0) {
10280 dtrace_ecb_destroy(ecb);
10281 return (NULL);
10282 }
10283 }
10284
10285 dtrace_ecb_resize(ecb);
10286
10287 return (dtrace_ecb_create_cache = ecb);
10288 }
10289
10290 static int
10291 dtrace_ecb_create_enable(dtrace_probe_t *probe, void *arg)
10292 {
10293 dtrace_ecb_t *ecb;
10294 dtrace_enabling_t *enab = arg;
10295 dtrace_state_t *state = enab->dten_vstate->dtvs_state;
10296
10297 ASSERT(state != NULL);
10298
10299 if (probe != NULL && probe->dtpr_gen < enab->dten_probegen) {
10300 /*
10301 * This probe was created in a generation for which this
10302 * enabling has previously created ECBs; we don't want to
10303 * enable it again, so just kick out.
10304 */
10305 return (DTRACE_MATCH_NEXT);
10306 }
10307
10308 if ((ecb = dtrace_ecb_create(state, probe, enab)) == NULL)
10309 return (DTRACE_MATCH_DONE);
10310
10311 if (dtrace_ecb_enable(ecb) < 0)
10312 return (DTRACE_MATCH_FAIL);
10313
10314 return (DTRACE_MATCH_NEXT);
10315 }
10316
10317 static dtrace_ecb_t *
10318 dtrace_epid2ecb(dtrace_state_t *state, dtrace_epid_t id)
10319 {
10320 dtrace_ecb_t *ecb;
10321
10322 ASSERT(MUTEX_HELD(&dtrace_lock));
10323
10324 if (id == 0 || id > state->dts_necbs)
10325 return (NULL);
10326
10327 ASSERT(state->dts_necbs > 0 && state->dts_ecbs != NULL);
10328 ASSERT((ecb = state->dts_ecbs[id - 1]) == NULL || ecb->dte_epid == id);
10329
10330 return (state->dts_ecbs[id - 1]);
10331 }
10332
10333 static dtrace_aggregation_t *
10334 dtrace_aggid2agg(dtrace_state_t *state, dtrace_aggid_t id)
10335 {
10336 dtrace_aggregation_t *agg;
10337
10338 ASSERT(MUTEX_HELD(&dtrace_lock));
10339
10340 if (id == 0 || id > state->dts_naggregations)
10341 return (NULL);
10342
10343 ASSERT(state->dts_naggregations > 0 && state->dts_aggregations != NULL);
10344 ASSERT((agg = state->dts_aggregations[id - 1]) == NULL ||
10345 agg->dtag_id == id);
10346
10347 return (state->dts_aggregations[id - 1]);
10348 }
10349
10350 /*
10351 * DTrace Buffer Functions
10352 *
10353 * The following functions manipulate DTrace buffers. Most of these functions
10354 * are called in the context of establishing or processing consumer state;
10355 * exceptions are explicitly noted.
10356 */
10357
10358 /*
10359 * Note: called from cross call context. This function switches the two
10360 * buffers on a given CPU. The atomicity of this operation is assured by
10361 * disabling interrupts while the actual switch takes place; the disabling of
10362 * interrupts serializes the execution with any execution of dtrace_probe() on
10363 * the same CPU.
10364 */
10365 static void
10366 dtrace_buffer_switch(dtrace_buffer_t *buf)
10367 {
10368 caddr_t tomax = buf->dtb_tomax;
10369 caddr_t xamot = buf->dtb_xamot;
10370 dtrace_icookie_t cookie;
10371 hrtime_t now;
10372
10373 ASSERT(!(buf->dtb_flags & DTRACEBUF_NOSWITCH));
10374 ASSERT(!(buf->dtb_flags & DTRACEBUF_RING));
10375
10376 cookie = dtrace_interrupt_disable();
10377 now = dtrace_gethrtime();
10378 buf->dtb_tomax = xamot;
10379 buf->dtb_xamot = tomax;
10380 buf->dtb_xamot_drops = buf->dtb_drops;
10381 buf->dtb_xamot_offset = buf->dtb_offset;
10382 buf->dtb_xamot_errors = buf->dtb_errors;
10383 buf->dtb_xamot_flags = buf->dtb_flags;
10384 buf->dtb_offset = 0;
10385 buf->dtb_drops = 0;
10386 buf->dtb_errors = 0;
10387 buf->dtb_flags &= ~(DTRACEBUF_ERROR | DTRACEBUF_DROPPED);
10388 buf->dtb_interval = now - buf->dtb_switched;
10389 buf->dtb_switched = now;
10390 dtrace_interrupt_enable(cookie);
10391 }
10392
10393 /*
10394 * Note: called from cross call context. This function activates a buffer
10395 * on a CPU. As with dtrace_buffer_switch(), the atomicity of the operation
10396 * is guaranteed by the disabling of interrupts.
10397 */
10398 static void
10399 dtrace_buffer_activate(dtrace_state_t *state)
10400 {
10401 dtrace_buffer_t *buf;
10402 dtrace_icookie_t cookie = dtrace_interrupt_disable();
10403
10404 buf = &state->dts_buffer[CPU->cpu_id];
10405
10406 if (buf->dtb_tomax != NULL) {
10407 /*
10408 * We might like to assert that the buffer is marked inactive,
10409 * but this isn't necessarily true: the buffer for the CPU
10410 * that processes the BEGIN probe has its buffer activated
10411 * manually. In this case, we take the (harmless) action
10412 * re-clearing the bit INACTIVE bit.
10413 */
10414 buf->dtb_flags &= ~DTRACEBUF_INACTIVE;
10415 }
10416
10417 dtrace_interrupt_enable(cookie);
10418 }
10419
10420 static int
10421 dtrace_buffer_alloc(dtrace_buffer_t *bufs, size_t size, int flags,
10422 processorid_t cpu, int *factor)
10423 {
10424 cpu_t *cp;
10425 dtrace_buffer_t *buf;
10426 int allocated = 0, desired = 0;
10427
10428 ASSERT(MUTEX_HELD(&cpu_lock));
10429 ASSERT(MUTEX_HELD(&dtrace_lock));
10430
10431 *factor = 1;
10432
10433 if (size > dtrace_nonroot_maxsize &&
10434 !PRIV_POLICY_CHOICE(CRED(), PRIV_ALL, B_FALSE))
10435 return (EFBIG);
10436
10437 cp = cpu_list;
10438
10439 do {
10440 if (cpu != DTRACE_CPUALL && cpu != cp->cpu_id)
10441 continue;
10442
10443 buf = &bufs[cp->cpu_id];
10444
10445 /*
10446 * If there is already a buffer allocated for this CPU, it
10447 * is only possible that this is a DR event. In this case,
10448 * the buffer size must match our specified size.
10449 */
10450 if (buf->dtb_tomax != NULL) {
10451 ASSERT(buf->dtb_size == size);
10452 continue;
10453 }
10454
10455 ASSERT(buf->dtb_xamot == NULL);
10456
10457 if ((buf->dtb_tomax = kmem_zalloc(size,
10458 KM_NOSLEEP | KM_NORMALPRI)) == NULL)
10459 goto err;
10460
10461 buf->dtb_size = size;
10462 buf->dtb_flags = flags;
10463 buf->dtb_offset = 0;
10464 buf->dtb_drops = 0;
10465
10466 if (flags & DTRACEBUF_NOSWITCH)
10467 continue;
10468
10469 if ((buf->dtb_xamot = kmem_zalloc(size,
10470 KM_NOSLEEP | KM_NORMALPRI)) == NULL)
10471 goto err;
10472 } while ((cp = cp->cpu_next) != cpu_list);
10473
10474 return (0);
10475
10476 err:
10477 cp = cpu_list;
10478
10479 do {
10480 if (cpu != DTRACE_CPUALL && cpu != cp->cpu_id)
10481 continue;
10482
10483 buf = &bufs[cp->cpu_id];
10484 desired += 2;
10485
10486 if (buf->dtb_xamot != NULL) {
10487 ASSERT(buf->dtb_tomax != NULL);
10488 ASSERT(buf->dtb_size == size);
10489 kmem_free(buf->dtb_xamot, size);
10490 allocated++;
10491 }
10492
10493 if (buf->dtb_tomax != NULL) {
10494 ASSERT(buf->dtb_size == size);
10495 kmem_free(buf->dtb_tomax, size);
10496 allocated++;
10497 }
10498
10499 buf->dtb_tomax = NULL;
10500 buf->dtb_xamot = NULL;
10501 buf->dtb_size = 0;
10502 } while ((cp = cp->cpu_next) != cpu_list);
10503
10504 *factor = desired / (allocated > 0 ? allocated : 1);
10505
10506 return (ENOMEM);
10507 }
10508
10509 /*
10510 * Note: called from probe context. This function just increments the drop
10511 * count on a buffer. It has been made a function to allow for the
10512 * possibility of understanding the source of mysterious drop counts. (A
10513 * problem for which one may be particularly disappointed that DTrace cannot
10514 * be used to understand DTrace.)
10515 */
10516 static void
10517 dtrace_buffer_drop(dtrace_buffer_t *buf)
10518 {
10519 buf->dtb_drops++;
10520 }
10521
10522 /*
10523 * Note: called from probe context. This function is called to reserve space
10524 * in a buffer. If mstate is non-NULL, sets the scratch base and size in the
10525 * mstate. Returns the new offset in the buffer, or a negative value if an
10526 * error has occurred.
10527 */
10528 static intptr_t
10529 dtrace_buffer_reserve(dtrace_buffer_t *buf, size_t needed, size_t align,
10530 dtrace_state_t *state, dtrace_mstate_t *mstate)
10531 {
10532 intptr_t offs = buf->dtb_offset, soffs;
10533 intptr_t woffs;
10534 caddr_t tomax;
10535 size_t total;
10536
10537 if (buf->dtb_flags & DTRACEBUF_INACTIVE)
10538 return (-1);
10539
10540 if ((tomax = buf->dtb_tomax) == NULL) {
10541 dtrace_buffer_drop(buf);
10542 return (-1);
10543 }
10544
10545 if (!(buf->dtb_flags & (DTRACEBUF_RING | DTRACEBUF_FILL))) {
10546 while (offs & (align - 1)) {
10547 /*
10548 * Assert that our alignment is off by a number which
10549 * is itself sizeof (uint32_t) aligned.
10550 */
10551 ASSERT(!((align - (offs & (align - 1))) &
10552 (sizeof (uint32_t) - 1)));
10553 DTRACE_STORE(uint32_t, tomax, offs, DTRACE_EPIDNONE);
10554 offs += sizeof (uint32_t);
10555 }
10556
10557 if ((soffs = offs + needed) > buf->dtb_size) {
10558 dtrace_buffer_drop(buf);
10559 return (-1);
10560 }
10561
10562 if (mstate == NULL)
10563 return (offs);
10564
10565 mstate->dtms_scratch_base = (uintptr_t)tomax + soffs;
10566 mstate->dtms_scratch_size = buf->dtb_size - soffs;
10567 mstate->dtms_scratch_ptr = mstate->dtms_scratch_base;
10568
10569 return (offs);
10570 }
10571
10572 if (buf->dtb_flags & DTRACEBUF_FILL) {
10573 if (state->dts_activity != DTRACE_ACTIVITY_COOLDOWN &&
10574 (buf->dtb_flags & DTRACEBUF_FULL))
10575 return (-1);
10576 goto out;
10577 }
10578
10579 total = needed + (offs & (align - 1));
10580
10581 /*
10582 * For a ring buffer, life is quite a bit more complicated. Before
10583 * we can store any padding, we need to adjust our wrapping offset.
10584 * (If we've never before wrapped or we're not about to, no adjustment
10585 * is required.)
10586 */
10587 if ((buf->dtb_flags & DTRACEBUF_WRAPPED) ||
10588 offs + total > buf->dtb_size) {
10589 woffs = buf->dtb_xamot_offset;
10590
10591 if (offs + total > buf->dtb_size) {
10592 /*
10593 * We can't fit in the end of the buffer. First, a
10594 * sanity check that we can fit in the buffer at all.
10595 */
10596 if (total > buf->dtb_size) {
10597 dtrace_buffer_drop(buf);
10598 return (-1);
10599 }
10600
10601 /*
10602 * We're going to be storing at the top of the buffer,
10603 * so now we need to deal with the wrapped offset. We
10604 * only reset our wrapped offset to 0 if it is
10605 * currently greater than the current offset. If it
10606 * is less than the current offset, it is because a
10607 * previous allocation induced a wrap -- but the
10608 * allocation didn't subsequently take the space due
10609 * to an error or false predicate evaluation. In this
10610 * case, we'll just leave the wrapped offset alone: if
10611 * the wrapped offset hasn't been advanced far enough
10612 * for this allocation, it will be adjusted in the
10613 * lower loop.
10614 */
10615 if (buf->dtb_flags & DTRACEBUF_WRAPPED) {
10616 if (woffs >= offs)
10617 woffs = 0;
10618 } else {
10619 woffs = 0;
10620 }
10621
10622 /*
10623 * Now we know that we're going to be storing to the
10624 * top of the buffer and that there is room for us
10625 * there. We need to clear the buffer from the current
10626 * offset to the end (there may be old gunk there).
10627 */
10628 while (offs < buf->dtb_size)
10629 tomax[offs++] = 0;
10630
10631 /*
10632 * We need to set our offset to zero. And because we
10633 * are wrapping, we need to set the bit indicating as
10634 * much. We can also adjust our needed space back
10635 * down to the space required by the ECB -- we know
10636 * that the top of the buffer is aligned.
10637 */
10638 offs = 0;
10639 total = needed;
10640 buf->dtb_flags |= DTRACEBUF_WRAPPED;
10641 } else {
10642 /*
10643 * There is room for us in the buffer, so we simply
10644 * need to check the wrapped offset.
10645 */
10646 if (woffs < offs) {
10647 /*
10648 * The wrapped offset is less than the offset.
10649 * This can happen if we allocated buffer space
10650 * that induced a wrap, but then we didn't
10651 * subsequently take the space due to an error
10652 * or false predicate evaluation. This is
10653 * okay; we know that _this_ allocation isn't
10654 * going to induce a wrap. We still can't
10655 * reset the wrapped offset to be zero,
10656 * however: the space may have been trashed in
10657 * the previous failed probe attempt. But at
10658 * least the wrapped offset doesn't need to
10659 * be adjusted at all...
10660 */
10661 goto out;
10662 }
10663 }
10664
10665 while (offs + total > woffs) {
10666 dtrace_epid_t epid = *(uint32_t *)(tomax + woffs);
10667 size_t size;
10668
10669 if (epid == DTRACE_EPIDNONE) {
10670 size = sizeof (uint32_t);
10671 } else {
10672 ASSERT3U(epid, <=, state->dts_necbs);
10673 ASSERT(state->dts_ecbs[epid - 1] != NULL);
10674
10675 size = state->dts_ecbs[epid - 1]->dte_size;
10676 }
10677
10678 ASSERT(woffs + size <= buf->dtb_size);
10679 ASSERT(size != 0);
10680
10681 if (woffs + size == buf->dtb_size) {
10682 /*
10683 * We've reached the end of the buffer; we want
10684 * to set the wrapped offset to 0 and break
10685 * out. However, if the offs is 0, then we're
10686 * in a strange edge-condition: the amount of
10687 * space that we want to reserve plus the size
10688 * of the record that we're overwriting is
10689 * greater than the size of the buffer. This
10690 * is problematic because if we reserve the
10691 * space but subsequently don't consume it (due
10692 * to a failed predicate or error) the wrapped
10693 * offset will be 0 -- yet the EPID at offset 0
10694 * will not be committed. This situation is
10695 * relatively easy to deal with: if we're in
10696 * this case, the buffer is indistinguishable
10697 * from one that hasn't wrapped; we need only
10698 * finish the job by clearing the wrapped bit,
10699 * explicitly setting the offset to be 0, and
10700 * zero'ing out the old data in the buffer.
10701 */
10702 if (offs == 0) {
10703 buf->dtb_flags &= ~DTRACEBUF_WRAPPED;
10704 buf->dtb_offset = 0;
10705 woffs = total;
10706
10707 while (woffs < buf->dtb_size)
10708 tomax[woffs++] = 0;
10709 }
10710
10711 woffs = 0;
10712 break;
10713 }
10714
10715 woffs += size;
10716 }
10717
10718 /*
10719 * We have a wrapped offset. It may be that the wrapped offset
10720 * has become zero -- that's okay.
10721 */
10722 buf->dtb_xamot_offset = woffs;
10723 }
10724
10725 out:
10726 /*
10727 * Now we can plow the buffer with any necessary padding.
10728 */
10729 while (offs & (align - 1)) {
10730 /*
10731 * Assert that our alignment is off by a number which
10732 * is itself sizeof (uint32_t) aligned.
10733 */
10734 ASSERT(!((align - (offs & (align - 1))) &
10735 (sizeof (uint32_t) - 1)));
10736 DTRACE_STORE(uint32_t, tomax, offs, DTRACE_EPIDNONE);
10737 offs += sizeof (uint32_t);
10738 }
10739
10740 if (buf->dtb_flags & DTRACEBUF_FILL) {
10741 if (offs + needed > buf->dtb_size - state->dts_reserve) {
10742 buf->dtb_flags |= DTRACEBUF_FULL;
10743 return (-1);
10744 }
10745 }
10746
10747 if (mstate == NULL)
10748 return (offs);
10749
10750 /*
10751 * For ring buffers and fill buffers, the scratch space is always
10752 * the inactive buffer.
10753 */
10754 mstate->dtms_scratch_base = (uintptr_t)buf->dtb_xamot;
10755 mstate->dtms_scratch_size = buf->dtb_size;
10756 mstate->dtms_scratch_ptr = mstate->dtms_scratch_base;
10757
10758 return (offs);
10759 }
10760
10761 static void
10762 dtrace_buffer_polish(dtrace_buffer_t *buf)
10763 {
10764 ASSERT(buf->dtb_flags & DTRACEBUF_RING);
10765 ASSERT(MUTEX_HELD(&dtrace_lock));
10766
10767 if (!(buf->dtb_flags & DTRACEBUF_WRAPPED))
10768 return;
10769
10770 /*
10771 * We need to polish the ring buffer. There are three cases:
10772 *
10773 * - The first (and presumably most common) is that there is no gap
10774 * between the buffer offset and the wrapped offset. In this case,
10775 * there is nothing in the buffer that isn't valid data; we can
10776 * mark the buffer as polished and return.
10777 *
10778 * - The second (less common than the first but still more common
10779 * than the third) is that there is a gap between the buffer offset
10780 * and the wrapped offset, and the wrapped offset is larger than the
10781 * buffer offset. This can happen because of an alignment issue, or
10782 * can happen because of a call to dtrace_buffer_reserve() that
10783 * didn't subsequently consume the buffer space. In this case,
10784 * we need to zero the data from the buffer offset to the wrapped
10785 * offset.
10786 *
10787 * - The third (and least common) is that there is a gap between the
10788 * buffer offset and the wrapped offset, but the wrapped offset is
10789 * _less_ than the buffer offset. This can only happen because a
10790 * call to dtrace_buffer_reserve() induced a wrap, but the space
10791 * was not subsequently consumed. In this case, we need to zero the
10792 * space from the offset to the end of the buffer _and_ from the
10793 * top of the buffer to the wrapped offset.
10794 */
10795 if (buf->dtb_offset < buf->dtb_xamot_offset) {
10796 bzero(buf->dtb_tomax + buf->dtb_offset,
10797 buf->dtb_xamot_offset - buf->dtb_offset);
10798 }
10799
10800 if (buf->dtb_offset > buf->dtb_xamot_offset) {
10801 bzero(buf->dtb_tomax + buf->dtb_offset,
10802 buf->dtb_size - buf->dtb_offset);
10803 bzero(buf->dtb_tomax, buf->dtb_xamot_offset);
10804 }
10805 }
10806
10807 /*
10808 * This routine determines if data generated at the specified time has likely
10809 * been entirely consumed at user-level. This routine is called to determine
10810 * if an ECB on a defunct probe (but for an active enabling) can be safely
10811 * disabled and destroyed.
10812 */
10813 static int
10814 dtrace_buffer_consumed(dtrace_buffer_t *bufs, hrtime_t when)
10815 {
10816 int i;
10817
10818 for (i = 0; i < NCPU; i++) {
10819 dtrace_buffer_t *buf = &bufs[i];
10820
10821 if (buf->dtb_size == 0)
10822 continue;
10823
10824 if (buf->dtb_flags & DTRACEBUF_RING)
10825 return (0);
10826
10827 if (!buf->dtb_switched && buf->dtb_offset != 0)
10828 return (0);
10829
10830 if (buf->dtb_switched - buf->dtb_interval < when)
10831 return (0);
10832 }
10833
10834 return (1);
10835 }
10836
10837 static void
10838 dtrace_buffer_free(dtrace_buffer_t *bufs)
10839 {
10840 int i;
10841
10842 for (i = 0; i < NCPU; i++) {
10843 dtrace_buffer_t *buf = &bufs[i];
10844
10845 if (buf->dtb_tomax == NULL) {
10846 ASSERT(buf->dtb_xamot == NULL);
10847 ASSERT(buf->dtb_size == 0);
10848 continue;
10849 }
10850
10851 if (buf->dtb_xamot != NULL) {
10852 ASSERT(!(buf->dtb_flags & DTRACEBUF_NOSWITCH));
10853 kmem_free(buf->dtb_xamot, buf->dtb_size);
10854 }
10855
10856 kmem_free(buf->dtb_tomax, buf->dtb_size);
10857 buf->dtb_size = 0;
10858 buf->dtb_tomax = NULL;
10859 buf->dtb_xamot = NULL;
10860 }
10861 }
10862
10863 /*
10864 * DTrace Enabling Functions
10865 */
10866 static dtrace_enabling_t *
10867 dtrace_enabling_create(dtrace_vstate_t *vstate)
10868 {
10869 dtrace_enabling_t *enab;
10870
10871 enab = kmem_zalloc(sizeof (dtrace_enabling_t), KM_SLEEP);
10872 enab->dten_vstate = vstate;
10873
10874 return (enab);
10875 }
10876
10877 static void
10878 dtrace_enabling_add(dtrace_enabling_t *enab, dtrace_ecbdesc_t *ecb)
10879 {
10880 dtrace_ecbdesc_t **ndesc;
10881 size_t osize, nsize;
10882
10883 /*
10884 * We can't add to enablings after we've enabled them, or after we've
10885 * retained them.
10886 */
10887 ASSERT(enab->dten_probegen == 0);
10888 ASSERT(enab->dten_next == NULL && enab->dten_prev == NULL);
10889
10890 if (enab->dten_ndesc < enab->dten_maxdesc) {
10891 enab->dten_desc[enab->dten_ndesc++] = ecb;
10892 return;
10893 }
10894
10895 osize = enab->dten_maxdesc * sizeof (dtrace_enabling_t *);
10896
10897 if (enab->dten_maxdesc == 0) {
10898 enab->dten_maxdesc = 1;
10899 } else {
10900 enab->dten_maxdesc <<= 1;
10901 }
10902
10903 ASSERT(enab->dten_ndesc < enab->dten_maxdesc);
10904
10905 nsize = enab->dten_maxdesc * sizeof (dtrace_enabling_t *);
10906 ndesc = kmem_zalloc(nsize, KM_SLEEP);
10907 bcopy(enab->dten_desc, ndesc, osize);
10908 kmem_free(enab->dten_desc, osize);
10909
10910 enab->dten_desc = ndesc;
10911 enab->dten_desc[enab->dten_ndesc++] = ecb;
10912 }
10913
10914 static void
10915 dtrace_enabling_addlike(dtrace_enabling_t *enab, dtrace_ecbdesc_t *ecb,
10916 dtrace_probedesc_t *pd)
10917 {
10918 dtrace_ecbdesc_t *new;
10919 dtrace_predicate_t *pred;
10920 dtrace_actdesc_t *act;
10921
10922 /*
10923 * We're going to create a new ECB description that matches the
10924 * specified ECB in every way, but has the specified probe description.
10925 */
10926 new = kmem_zalloc(sizeof (dtrace_ecbdesc_t), KM_SLEEP);
10927
10928 if ((pred = ecb->dted_pred.dtpdd_predicate) != NULL)
10929 dtrace_predicate_hold(pred);
10930
10931 for (act = ecb->dted_action; act != NULL; act = act->dtad_next)
10932 dtrace_actdesc_hold(act);
10933
10934 new->dted_action = ecb->dted_action;
10935 new->dted_pred = ecb->dted_pred;
10936 new->dted_probe = *pd;
10937 new->dted_uarg = ecb->dted_uarg;
10938
10939 dtrace_enabling_add(enab, new);
10940 }
10941
10942 static void
10943 dtrace_enabling_dump(dtrace_enabling_t *enab)
10944 {
10945 int i;
10946
10947 for (i = 0; i < enab->dten_ndesc; i++) {
10948 dtrace_probedesc_t *desc = &enab->dten_desc[i]->dted_probe;
10949
10950 cmn_err(CE_NOTE, "enabling probe %d (%s:%s:%s:%s)", i,
10951 desc->dtpd_provider, desc->dtpd_mod,
10952 desc->dtpd_func, desc->dtpd_name);
10953 }
10954 }
10955
10956 static void
10957 dtrace_enabling_destroy(dtrace_enabling_t *enab)
10958 {
10959 int i;
10960 dtrace_ecbdesc_t *ep;
10961 dtrace_vstate_t *vstate = enab->dten_vstate;
10962
10963 ASSERT(MUTEX_HELD(&dtrace_lock));
10964
10965 for (i = 0; i < enab->dten_ndesc; i++) {
10966 dtrace_actdesc_t *act, *next;
10967 dtrace_predicate_t *pred;
10968
10969 ep = enab->dten_desc[i];
10970
10971 if ((pred = ep->dted_pred.dtpdd_predicate) != NULL)
10972 dtrace_predicate_release(pred, vstate);
10973
10974 for (act = ep->dted_action; act != NULL; act = next) {
10975 next = act->dtad_next;
10976 dtrace_actdesc_release(act, vstate);
10977 }
10978
10979 kmem_free(ep, sizeof (dtrace_ecbdesc_t));
10980 }
10981
10982 kmem_free(enab->dten_desc,
10983 enab->dten_maxdesc * sizeof (dtrace_enabling_t *));
10984
10985 /*
10986 * If this was a retained enabling, decrement the dts_nretained count
10987 * and take it off of the dtrace_retained list.
10988 */
10989 if (enab->dten_prev != NULL || enab->dten_next != NULL ||
10990 dtrace_retained == enab) {
10991 ASSERT(enab->dten_vstate->dtvs_state != NULL);
10992 ASSERT(enab->dten_vstate->dtvs_state->dts_nretained > 0);
10993 enab->dten_vstate->dtvs_state->dts_nretained--;
10994 dtrace_retained_gen++;
10995 }
10996
10997 if (enab->dten_prev == NULL) {
10998 if (dtrace_retained == enab) {
10999 dtrace_retained = enab->dten_next;
11000
11001 if (dtrace_retained != NULL)
11002 dtrace_retained->dten_prev = NULL;
11003 }
11004 } else {
11005 ASSERT(enab != dtrace_retained);
11006 ASSERT(dtrace_retained != NULL);
11007 enab->dten_prev->dten_next = enab->dten_next;
11008 }
11009
11010 if (enab->dten_next != NULL) {
11011 ASSERT(dtrace_retained != NULL);
11012 enab->dten_next->dten_prev = enab->dten_prev;
11013 }
11014
11015 kmem_free(enab, sizeof (dtrace_enabling_t));
11016 }
11017
11018 static int
11019 dtrace_enabling_retain(dtrace_enabling_t *enab)
11020 {
11021 dtrace_state_t *state;
11022
11023 ASSERT(MUTEX_HELD(&dtrace_lock));
11024 ASSERT(enab->dten_next == NULL && enab->dten_prev == NULL);
11025 ASSERT(enab->dten_vstate != NULL);
11026
11027 state = enab->dten_vstate->dtvs_state;
11028 ASSERT(state != NULL);
11029
11030 /*
11031 * We only allow each state to retain dtrace_retain_max enablings.
11032 */
11033 if (state->dts_nretained >= dtrace_retain_max)
11034 return (ENOSPC);
11035
11036 state->dts_nretained++;
11037 dtrace_retained_gen++;
11038
11039 if (dtrace_retained == NULL) {
11040 dtrace_retained = enab;
11041 return (0);
11042 }
11043
11044 enab->dten_next = dtrace_retained;
11045 dtrace_retained->dten_prev = enab;
11046 dtrace_retained = enab;
11047
11048 return (0);
11049 }
11050
11051 static int
11052 dtrace_enabling_replicate(dtrace_state_t *state, dtrace_probedesc_t *match,
11053 dtrace_probedesc_t *create)
11054 {
11055 dtrace_enabling_t *new, *enab;
11056 int found = 0, err = ENOENT;
11057
11058 ASSERT(MUTEX_HELD(&dtrace_lock));
11059 ASSERT(strlen(match->dtpd_provider) < DTRACE_PROVNAMELEN);
11060 ASSERT(strlen(match->dtpd_mod) < DTRACE_MODNAMELEN);
11061 ASSERT(strlen(match->dtpd_func) < DTRACE_FUNCNAMELEN);
11062 ASSERT(strlen(match->dtpd_name) < DTRACE_NAMELEN);
11063
11064 new = dtrace_enabling_create(&state->dts_vstate);
11065
11066 /*
11067 * Iterate over all retained enablings, looking for enablings that
11068 * match the specified state.
11069 */
11070 for (enab = dtrace_retained; enab != NULL; enab = enab->dten_next) {
11071 int i;
11072
11073 /*
11074 * dtvs_state can only be NULL for helper enablings -- and
11075 * helper enablings can't be retained.
11076 */
11077 ASSERT(enab->dten_vstate->dtvs_state != NULL);
11078
11079 if (enab->dten_vstate->dtvs_state != state)
11080 continue;
11081
11082 /*
11083 * Now iterate over each probe description; we're looking for
11084 * an exact match to the specified probe description.
11085 */
11086 for (i = 0; i < enab->dten_ndesc; i++) {
11087 dtrace_ecbdesc_t *ep = enab->dten_desc[i];
11088 dtrace_probedesc_t *pd = &ep->dted_probe;
11089
11090 if (strcmp(pd->dtpd_provider, match->dtpd_provider))
11091 continue;
11092
11093 if (strcmp(pd->dtpd_mod, match->dtpd_mod))
11094 continue;
11095
11096 if (strcmp(pd->dtpd_func, match->dtpd_func))
11097 continue;
11098
11099 if (strcmp(pd->dtpd_name, match->dtpd_name))
11100 continue;
11101
11102 /*
11103 * We have a winning probe! Add it to our growing
11104 * enabling.
11105 */
11106 found = 1;
11107 dtrace_enabling_addlike(new, ep, create);
11108 }
11109 }
11110
11111 if (!found || (err = dtrace_enabling_retain(new)) != 0) {
11112 dtrace_enabling_destroy(new);
11113 return (err);
11114 }
11115
11116 return (0);
11117 }
11118
11119 static void
11120 dtrace_enabling_retract(dtrace_state_t *state)
11121 {
11122 dtrace_enabling_t *enab, *next;
11123
11124 ASSERT(MUTEX_HELD(&dtrace_lock));
11125
11126 /*
11127 * Iterate over all retained enablings, destroy the enablings retained
11128 * for the specified state.
11129 */
11130 for (enab = dtrace_retained; enab != NULL; enab = next) {
11131 next = enab->dten_next;
11132
11133 /*
11134 * dtvs_state can only be NULL for helper enablings -- and
11135 * helper enablings can't be retained.
11136 */
11137 ASSERT(enab->dten_vstate->dtvs_state != NULL);
11138
11139 if (enab->dten_vstate->dtvs_state == state) {
11140 ASSERT(state->dts_nretained > 0);
11141 dtrace_enabling_destroy(enab);
11142 }
11143 }
11144
11145 ASSERT(state->dts_nretained == 0);
11146 }
11147
11148 static int
11149 dtrace_enabling_match(dtrace_enabling_t *enab, int *nmatched)
11150 {
11151 int i = 0;
11152 int total_matched = 0, matched = 0;
11153
11154 ASSERT(MUTEX_HELD(&cpu_lock));
11155 ASSERT(MUTEX_HELD(&dtrace_lock));
11156
11157 for (i = 0; i < enab->dten_ndesc; i++) {
11158 dtrace_ecbdesc_t *ep = enab->dten_desc[i];
11159
11160 enab->dten_current = ep;
11161 enab->dten_error = 0;
11162
11163 /*
11164 * If a provider failed to enable a probe then get out and
11165 * let the consumer know we failed.
11166 */
11167 if ((matched = dtrace_probe_enable(&ep->dted_probe, enab)) < 0)
11168 return (EBUSY);
11169
11170 total_matched += matched;
11171
11172 if (enab->dten_error != 0) {
11173 /*
11174 * If we get an error half-way through enabling the
11175 * probes, we kick out -- perhaps with some number of
11176 * them enabled. Leaving enabled probes enabled may
11177 * be slightly confusing for user-level, but we expect
11178 * that no one will attempt to actually drive on in
11179 * the face of such errors. If this is an anonymous
11180 * enabling (indicated with a NULL nmatched pointer),
11181 * we cmn_err() a message. We aren't expecting to
11182 * get such an error -- such as it can exist at all,
11183 * it would be a result of corrupted DOF in the driver
11184 * properties.
11185 */
11186 if (nmatched == NULL) {
11187 cmn_err(CE_WARN, "dtrace_enabling_match() "
11188 "error on %p: %d", (void *)ep,
11189 enab->dten_error);
11190 }
11191
11192 return (enab->dten_error);
11193 }
11194 }
11195
11196 enab->dten_probegen = dtrace_probegen;
11197 if (nmatched != NULL)
11198 *nmatched = total_matched;
11199
11200 return (0);
11201 }
11202
11203 static void
11204 dtrace_enabling_matchall(void)
11205 {
11206 dtrace_enabling_t *enab;
11207
11208 mutex_enter(&cpu_lock);
11209 mutex_enter(&dtrace_lock);
11210
11211 /*
11212 * Iterate over all retained enablings to see if any probes match
11213 * against them. We only perform this operation on enablings for which
11214 * we have sufficient permissions by virtue of being in the global zone
11215 * or in the same zone as the DTrace client. Because we can be called
11216 * after dtrace_detach() has been called, we cannot assert that there
11217 * are retained enablings. We can safely load from dtrace_retained,
11218 * however: the taskq_destroy() at the end of dtrace_detach() will
11219 * block pending our completion.
11220 */
11221 for (enab = dtrace_retained; enab != NULL; enab = enab->dten_next) {
11222 dtrace_cred_t *dcr = &enab->dten_vstate->dtvs_state->dts_cred;
11223 cred_t *cr = dcr->dcr_cred;
11224 zoneid_t zone = cr != NULL ? crgetzoneid(cr) : 0;
11225
11226 if ((dcr->dcr_visible & DTRACE_CRV_ALLZONE) || (cr != NULL &&
11227 (zone == GLOBAL_ZONEID || getzoneid() == zone)))
11228 (void) dtrace_enabling_match(enab, NULL);
11229 }
11230
11231 mutex_exit(&dtrace_lock);
11232 mutex_exit(&cpu_lock);
11233 }
11234
11235 /*
11236 * If an enabling is to be enabled without having matched probes (that is, if
11237 * dtrace_state_go() is to be called on the underlying dtrace_state_t), the
11238 * enabling must be _primed_ by creating an ECB for every ECB description.
11239 * This must be done to assure that we know the number of speculations, the
11240 * number of aggregations, the minimum buffer size needed, etc. before we
11241 * transition out of DTRACE_ACTIVITY_INACTIVE. To do this without actually
11242 * enabling any probes, we create ECBs for every ECB decription, but with a
11243 * NULL probe -- which is exactly what this function does.
11244 */
11245 static void
11246 dtrace_enabling_prime(dtrace_state_t *state)
11247 {
11248 dtrace_enabling_t *enab;
11249 int i;
11250
11251 for (enab = dtrace_retained; enab != NULL; enab = enab->dten_next) {
11252 ASSERT(enab->dten_vstate->dtvs_state != NULL);
11253
11254 if (enab->dten_vstate->dtvs_state != state)
11255 continue;
11256
11257 /*
11258 * We don't want to prime an enabling more than once, lest
11259 * we allow a malicious user to induce resource exhaustion.
11260 * (The ECBs that result from priming an enabling aren't
11261 * leaked -- but they also aren't deallocated until the
11262 * consumer state is destroyed.)
11263 */
11264 if (enab->dten_primed)
11265 continue;
11266
11267 for (i = 0; i < enab->dten_ndesc; i++) {
11268 enab->dten_current = enab->dten_desc[i];
11269 (void) dtrace_probe_enable(NULL, enab);
11270 }
11271
11272 enab->dten_primed = 1;
11273 }
11274 }
11275
11276 /*
11277 * Called to indicate that probes should be provided due to retained
11278 * enablings. This is implemented in terms of dtrace_probe_provide(), but it
11279 * must take an initial lap through the enabling calling the dtps_provide()
11280 * entry point explicitly to allow for autocreated probes.
11281 */
11282 static void
11283 dtrace_enabling_provide(dtrace_provider_t *prv)
11284 {
11285 int i, all = 0;
11286 dtrace_probedesc_t desc;
11287 dtrace_genid_t gen;
11288
11289 ASSERT(MUTEX_HELD(&dtrace_lock));
11290 ASSERT(MUTEX_HELD(&dtrace_provider_lock));
11291
11292 if (prv == NULL) {
11293 all = 1;
11294 prv = dtrace_provider;
11295 }
11296
11297 do {
11298 dtrace_enabling_t *enab;
11299 void *parg = prv->dtpv_arg;
11300
11301 retry:
11302 gen = dtrace_retained_gen;
11303 for (enab = dtrace_retained; enab != NULL;
11304 enab = enab->dten_next) {
11305 for (i = 0; i < enab->dten_ndesc; i++) {
11306 desc = enab->dten_desc[i]->dted_probe;
11307 mutex_exit(&dtrace_lock);
11308 prv->dtpv_pops.dtps_provide(parg, &desc);
11309 mutex_enter(&dtrace_lock);
11310 /*
11311 * Process the retained enablings again if
11312 * they have changed while we weren't holding
11313 * dtrace_lock.
11314 */
11315 if (gen != dtrace_retained_gen)
11316 goto retry;
11317 }
11318 }
11319 } while (all && (prv = prv->dtpv_next) != NULL);
11320
11321 mutex_exit(&dtrace_lock);
11322 dtrace_probe_provide(NULL, all ? NULL : prv);
11323 mutex_enter(&dtrace_lock);
11324 }
11325
11326 /*
11327 * Called to reap ECBs that are attached to probes from defunct providers.
11328 */
11329 static void
11330 dtrace_enabling_reap(void)
11331 {
11332 dtrace_provider_t *prov;
11333 dtrace_probe_t *probe;
11334 dtrace_ecb_t *ecb;
11335 hrtime_t when;
11336 int i;
11337
11338 mutex_enter(&cpu_lock);
11339 mutex_enter(&dtrace_lock);
11340
11341 for (i = 0; i < dtrace_nprobes; i++) {
11342 if ((probe = dtrace_probes[i]) == NULL)
11343 continue;
11344
11345 if (probe->dtpr_ecb == NULL)
11346 continue;
11347
11348 prov = probe->dtpr_provider;
11349
11350 if ((when = prov->dtpv_defunct) == 0)
11351 continue;
11352
11353 /*
11354 * We have ECBs on a defunct provider: we want to reap these
11355 * ECBs to allow the provider to unregister. The destruction
11356 * of these ECBs must be done carefully: if we destroy the ECB
11357 * and the consumer later wishes to consume an EPID that
11358 * corresponds to the destroyed ECB (and if the EPID metadata
11359 * has not been previously consumed), the consumer will abort
11360 * processing on the unknown EPID. To reduce (but not, sadly,
11361 * eliminate) the possibility of this, we will only destroy an
11362 * ECB for a defunct provider if, for the state that
11363 * corresponds to the ECB:
11364 *
11365 * (a) There is no speculative tracing (which can effectively
11366 * cache an EPID for an arbitrary amount of time).
11367 *
11368 * (b) The principal buffers have been switched twice since the
11369 * provider became defunct.
11370 *
11371 * (c) The aggregation buffers are of zero size or have been
11372 * switched twice since the provider became defunct.
11373 *
11374 * We use dts_speculates to determine (a) and call a function
11375 * (dtrace_buffer_consumed()) to determine (b) and (c). Note
11376 * that as soon as we've been unable to destroy one of the ECBs
11377 * associated with the probe, we quit trying -- reaping is only
11378 * fruitful in as much as we can destroy all ECBs associated
11379 * with the defunct provider's probes.
11380 */
11381 while ((ecb = probe->dtpr_ecb) != NULL) {
11382 dtrace_state_t *state = ecb->dte_state;
11383 dtrace_buffer_t *buf = state->dts_buffer;
11384 dtrace_buffer_t *aggbuf = state->dts_aggbuffer;
11385
11386 if (state->dts_speculates)
11387 break;
11388
11389 if (!dtrace_buffer_consumed(buf, when))
11390 break;
11391
11392 if (!dtrace_buffer_consumed(aggbuf, when))
11393 break;
11394
11395 dtrace_ecb_disable(ecb);
11396 ASSERT(probe->dtpr_ecb != ecb);
11397 dtrace_ecb_destroy(ecb);
11398 }
11399 }
11400
11401 mutex_exit(&dtrace_lock);
11402 mutex_exit(&cpu_lock);
11403 }
11404
11405 /*
11406 * DTrace DOF Functions
11407 */
11408 /*ARGSUSED*/
11409 static void
11410 dtrace_dof_error(dof_hdr_t *dof, const char *str)
11411 {
11412 if (dtrace_err_verbose)
11413 cmn_err(CE_WARN, "failed to process DOF: %s", str);
11414
11415 #ifdef DTRACE_ERRDEBUG
11416 dtrace_errdebug(str);
11417 #endif
11418 }
11419
11420 /*
11421 * Create DOF out of a currently enabled state. Right now, we only create
11422 * DOF containing the run-time options -- but this could be expanded to create
11423 * complete DOF representing the enabled state.
11424 */
11425 static dof_hdr_t *
11426 dtrace_dof_create(dtrace_state_t *state)
11427 {
11428 dof_hdr_t *dof;
11429 dof_sec_t *sec;
11430 dof_optdesc_t *opt;
11431 int i, len = sizeof (dof_hdr_t) +
11432 roundup(sizeof (dof_sec_t), sizeof (uint64_t)) +
11433 sizeof (dof_optdesc_t) * DTRACEOPT_MAX;
11434
11435 ASSERT(MUTEX_HELD(&dtrace_lock));
11436
11437 dof = kmem_zalloc(len, KM_SLEEP);
11438 dof->dofh_ident[DOF_ID_MAG0] = DOF_MAG_MAG0;
11439 dof->dofh_ident[DOF_ID_MAG1] = DOF_MAG_MAG1;
11440 dof->dofh_ident[DOF_ID_MAG2] = DOF_MAG_MAG2;
11441 dof->dofh_ident[DOF_ID_MAG3] = DOF_MAG_MAG3;
11442
11443 dof->dofh_ident[DOF_ID_MODEL] = DOF_MODEL_NATIVE;
11444 dof->dofh_ident[DOF_ID_ENCODING] = DOF_ENCODE_NATIVE;
11445 dof->dofh_ident[DOF_ID_VERSION] = DOF_VERSION;
11446 dof->dofh_ident[DOF_ID_DIFVERS] = DIF_VERSION;
11447 dof->dofh_ident[DOF_ID_DIFIREG] = DIF_DIR_NREGS;
11448 dof->dofh_ident[DOF_ID_DIFTREG] = DIF_DTR_NREGS;
11449
11450 dof->dofh_flags = 0;
11451 dof->dofh_hdrsize = sizeof (dof_hdr_t);
11452 dof->dofh_secsize = sizeof (dof_sec_t);
11453 dof->dofh_secnum = 1; /* only DOF_SECT_OPTDESC */
11454 dof->dofh_secoff = sizeof (dof_hdr_t);
11455 dof->dofh_loadsz = len;
11456 dof->dofh_filesz = len;
11457 dof->dofh_pad = 0;
11458
11459 /*
11460 * Fill in the option section header...
11461 */
11462 sec = (dof_sec_t *)((uintptr_t)dof + sizeof (dof_hdr_t));
11463 sec->dofs_type = DOF_SECT_OPTDESC;
11464 sec->dofs_align = sizeof (uint64_t);
11465 sec->dofs_flags = DOF_SECF_LOAD;
11466 sec->dofs_entsize = sizeof (dof_optdesc_t);
11467
11468 opt = (dof_optdesc_t *)((uintptr_t)sec +
11469 roundup(sizeof (dof_sec_t), sizeof (uint64_t)));
11470
11471 sec->dofs_offset = (uintptr_t)opt - (uintptr_t)dof;
11472 sec->dofs_size = sizeof (dof_optdesc_t) * DTRACEOPT_MAX;
11473
11474 for (i = 0; i < DTRACEOPT_MAX; i++) {
11475 opt[i].dofo_option = i;
11476 opt[i].dofo_strtab = DOF_SECIDX_NONE;
11477 opt[i].dofo_value = state->dts_options[i];
11478 }
11479
11480 return (dof);
11481 }
11482
11483 static dof_hdr_t *
11484 dtrace_dof_copyin(uintptr_t uarg, int *errp)
11485 {
11486 dof_hdr_t hdr, *dof;
11487
11488 ASSERT(!MUTEX_HELD(&dtrace_lock));
11489
11490 /*
11491 * First, we're going to copyin() the sizeof (dof_hdr_t).
11492 */
11493 if (copyin((void *)uarg, &hdr, sizeof (hdr)) != 0) {
11494 dtrace_dof_error(NULL, "failed to copyin DOF header");
11495 *errp = EFAULT;
11496 return (NULL);
11497 }
11498
11499 /*
11500 * Now we'll allocate the entire DOF and copy it in -- provided
11501 * that the length isn't outrageous.
11502 */
11503 if (hdr.dofh_loadsz >= dtrace_dof_maxsize) {
11504 dtrace_dof_error(&hdr, "load size exceeds maximum");
11505 *errp = E2BIG;
11506 return (NULL);
11507 }
11508
11509 if (hdr.dofh_loadsz < sizeof (hdr)) {
11510 dtrace_dof_error(&hdr, "invalid load size");
11511 *errp = EINVAL;
11512 return (NULL);
11513 }
11514
11515 dof = kmem_alloc(hdr.dofh_loadsz, KM_SLEEP);
11516
11517 if (copyin((void *)uarg, dof, hdr.dofh_loadsz) != 0 ||
11518 dof->dofh_loadsz != hdr.dofh_loadsz) {
11519 kmem_free(dof, hdr.dofh_loadsz);
11520 *errp = EFAULT;
11521 return (NULL);
11522 }
11523
11524 return (dof);
11525 }
11526
11527 static dof_hdr_t *
11528 dtrace_dof_property(const char *name)
11529 {
11530 uchar_t *buf;
11531 uint64_t loadsz;
11532 unsigned int len, i;
11533 dof_hdr_t *dof;
11534
11535 /*
11536 * Unfortunately, array of values in .conf files are always (and
11537 * only) interpreted to be integer arrays. We must read our DOF
11538 * as an integer array, and then squeeze it into a byte array.
11539 */
11540 if (ddi_prop_lookup_int_array(DDI_DEV_T_ANY, dtrace_devi, 0,
11541 (char *)name, (int **)&buf, &len) != DDI_PROP_SUCCESS)
11542 return (NULL);
11543
11544 for (i = 0; i < len; i++)
11545 buf[i] = (uchar_t)(((int *)buf)[i]);
11546
11547 if (len < sizeof (dof_hdr_t)) {
11548 ddi_prop_free(buf);
11549 dtrace_dof_error(NULL, "truncated header");
11550 return (NULL);
11551 }
11552
11553 if (len < (loadsz = ((dof_hdr_t *)buf)->dofh_loadsz)) {
11554 ddi_prop_free(buf);
11555 dtrace_dof_error(NULL, "truncated DOF");
11556 return (NULL);
11557 }
11558
11559 if (loadsz >= dtrace_dof_maxsize) {
11560 ddi_prop_free(buf);
11561 dtrace_dof_error(NULL, "oversized DOF");
11562 return (NULL);
11563 }
11564
11565 dof = kmem_alloc(loadsz, KM_SLEEP);
11566 bcopy(buf, dof, loadsz);
11567 ddi_prop_free(buf);
11568
11569 return (dof);
11570 }
11571
11572 static void
11573 dtrace_dof_destroy(dof_hdr_t *dof)
11574 {
11575 kmem_free(dof, dof->dofh_loadsz);
11576 }
11577
11578 /*
11579 * Return the dof_sec_t pointer corresponding to a given section index. If the
11580 * index is not valid, dtrace_dof_error() is called and NULL is returned. If
11581 * a type other than DOF_SECT_NONE is specified, the header is checked against
11582 * this type and NULL is returned if the types do not match.
11583 */
11584 static dof_sec_t *
11585 dtrace_dof_sect(dof_hdr_t *dof, uint32_t type, dof_secidx_t i)
11586 {
11587 dof_sec_t *sec = (dof_sec_t *)(uintptr_t)
11588 ((uintptr_t)dof + dof->dofh_secoff + i * dof->dofh_secsize);
11589
11590 if (i >= dof->dofh_secnum) {
11591 dtrace_dof_error(dof, "referenced section index is invalid");
11592 return (NULL);
11593 }
11594
11595 if (!(sec->dofs_flags & DOF_SECF_LOAD)) {
11596 dtrace_dof_error(dof, "referenced section is not loadable");
11597 return (NULL);
11598 }
11599
11600 if (type != DOF_SECT_NONE && type != sec->dofs_type) {
11601 dtrace_dof_error(dof, "referenced section is the wrong type");
11602 return (NULL);
11603 }
11604
11605 return (sec);
11606 }
11607
11608 static dtrace_probedesc_t *
11609 dtrace_dof_probedesc(dof_hdr_t *dof, dof_sec_t *sec, dtrace_probedesc_t *desc)
11610 {
11611 dof_probedesc_t *probe;
11612 dof_sec_t *strtab;
11613 uintptr_t daddr = (uintptr_t)dof;
11614 uintptr_t str;
11615 size_t size;
11616
11617 if (sec->dofs_type != DOF_SECT_PROBEDESC) {
11618 dtrace_dof_error(dof, "invalid probe section");
11619 return (NULL);
11620 }
11621
11622 if (sec->dofs_align != sizeof (dof_secidx_t)) {
11623 dtrace_dof_error(dof, "bad alignment in probe description");
11624 return (NULL);
11625 }
11626
11627 if (sec->dofs_offset + sizeof (dof_probedesc_t) > dof->dofh_loadsz) {
11628 dtrace_dof_error(dof, "truncated probe description");
11629 return (NULL);
11630 }
11631
11632 probe = (dof_probedesc_t *)(uintptr_t)(daddr + sec->dofs_offset);
11633 strtab = dtrace_dof_sect(dof, DOF_SECT_STRTAB, probe->dofp_strtab);
11634
11635 if (strtab == NULL)
11636 return (NULL);
11637
11638 str = daddr + strtab->dofs_offset;
11639 size = strtab->dofs_size;
11640
11641 if (probe->dofp_provider >= strtab->dofs_size) {
11642 dtrace_dof_error(dof, "corrupt probe provider");
11643 return (NULL);
11644 }
11645
11646 (void) strncpy(desc->dtpd_provider,
11647 (char *)(str + probe->dofp_provider),
11648 MIN(DTRACE_PROVNAMELEN - 1, size - probe->dofp_provider));
11649
11650 if (probe->dofp_mod >= strtab->dofs_size) {
11651 dtrace_dof_error(dof, "corrupt probe module");
11652 return (NULL);
11653 }
11654
11655 (void) strncpy(desc->dtpd_mod, (char *)(str + probe->dofp_mod),
11656 MIN(DTRACE_MODNAMELEN - 1, size - probe->dofp_mod));
11657
11658 if (probe->dofp_func >= strtab->dofs_size) {
11659 dtrace_dof_error(dof, "corrupt probe function");
11660 return (NULL);
11661 }
11662
11663 (void) strncpy(desc->dtpd_func, (char *)(str + probe->dofp_func),
11664 MIN(DTRACE_FUNCNAMELEN - 1, size - probe->dofp_func));
11665
11666 if (probe->dofp_name >= strtab->dofs_size) {
11667 dtrace_dof_error(dof, "corrupt probe name");
11668 return (NULL);
11669 }
11670
11671 (void) strncpy(desc->dtpd_name, (char *)(str + probe->dofp_name),
11672 MIN(DTRACE_NAMELEN - 1, size - probe->dofp_name));
11673
11674 return (desc);
11675 }
11676
11677 static dtrace_difo_t *
11678 dtrace_dof_difo(dof_hdr_t *dof, dof_sec_t *sec, dtrace_vstate_t *vstate,
11679 cred_t *cr)
11680 {
11681 dtrace_difo_t *dp;
11682 size_t ttl = 0;
11683 dof_difohdr_t *dofd;
11684 uintptr_t daddr = (uintptr_t)dof;
11685 size_t max = dtrace_difo_maxsize;
11686 int i, l, n;
11687
11688 static const struct {
11689 int section;
11690 int bufoffs;
11691 int lenoffs;
11692 int entsize;
11693 int align;
11694 const char *msg;
11695 } difo[] = {
11696 { DOF_SECT_DIF, offsetof(dtrace_difo_t, dtdo_buf),
11697 offsetof(dtrace_difo_t, dtdo_len), sizeof (dif_instr_t),
11698 sizeof (dif_instr_t), "multiple DIF sections" },
11699
11700 { DOF_SECT_INTTAB, offsetof(dtrace_difo_t, dtdo_inttab),
11701 offsetof(dtrace_difo_t, dtdo_intlen), sizeof (uint64_t),
11702 sizeof (uint64_t), "multiple integer tables" },
11703
11704 { DOF_SECT_STRTAB, offsetof(dtrace_difo_t, dtdo_strtab),
11705 offsetof(dtrace_difo_t, dtdo_strlen), 0,
11706 sizeof (char), "multiple string tables" },
11707
11708 { DOF_SECT_VARTAB, offsetof(dtrace_difo_t, dtdo_vartab),
11709 offsetof(dtrace_difo_t, dtdo_varlen), sizeof (dtrace_difv_t),
11710 sizeof (uint_t), "multiple variable tables" },
11711
11712 { DOF_SECT_NONE, 0, 0, 0, NULL }
11713 };
11714
11715 if (sec->dofs_type != DOF_SECT_DIFOHDR) {
11716 dtrace_dof_error(dof, "invalid DIFO header section");
11717 return (NULL);
11718 }
11719
11720 if (sec->dofs_align != sizeof (dof_secidx_t)) {
11721 dtrace_dof_error(dof, "bad alignment in DIFO header");
11722 return (NULL);
11723 }
11724
11725 if (sec->dofs_size < sizeof (dof_difohdr_t) ||
11726 sec->dofs_size % sizeof (dof_secidx_t)) {
11727 dtrace_dof_error(dof, "bad size in DIFO header");
11728 return (NULL);
11729 }
11730
11731 dofd = (dof_difohdr_t *)(uintptr_t)(daddr + sec->dofs_offset);
11732 n = (sec->dofs_size - sizeof (*dofd)) / sizeof (dof_secidx_t) + 1;
11733
11734 dp = kmem_zalloc(sizeof (dtrace_difo_t), KM_SLEEP);
11735 dp->dtdo_rtype = dofd->dofd_rtype;
11736
11737 for (l = 0; l < n; l++) {
11738 dof_sec_t *subsec;
11739 void **bufp;
11740 uint32_t *lenp;
11741
11742 if ((subsec = dtrace_dof_sect(dof, DOF_SECT_NONE,
11743 dofd->dofd_links[l])) == NULL)
11744 goto err; /* invalid section link */
11745
11746 if (ttl + subsec->dofs_size > max) {
11747 dtrace_dof_error(dof, "exceeds maximum size");
11748 goto err;
11749 }
11750
11751 ttl += subsec->dofs_size;
11752
11753 for (i = 0; difo[i].section != DOF_SECT_NONE; i++) {
11754 if (subsec->dofs_type != difo[i].section)
11755 continue;
11756
11757 if (!(subsec->dofs_flags & DOF_SECF_LOAD)) {
11758 dtrace_dof_error(dof, "section not loaded");
11759 goto err;
11760 }
11761
11762 if (subsec->dofs_align != difo[i].align) {
11763 dtrace_dof_error(dof, "bad alignment");
11764 goto err;
11765 }
11766
11767 bufp = (void **)((uintptr_t)dp + difo[i].bufoffs);
11768 lenp = (uint32_t *)((uintptr_t)dp + difo[i].lenoffs);
11769
11770 if (*bufp != NULL) {
11771 dtrace_dof_error(dof, difo[i].msg);
11772 goto err;
11773 }
11774
11775 if (difo[i].entsize != subsec->dofs_entsize) {
11776 dtrace_dof_error(dof, "entry size mismatch");
11777 goto err;
11778 }
11779
11780 if (subsec->dofs_entsize != 0 &&
11781 (subsec->dofs_size % subsec->dofs_entsize) != 0) {
11782 dtrace_dof_error(dof, "corrupt entry size");
11783 goto err;
11784 }
11785
11786 *lenp = subsec->dofs_size;
11787 *bufp = kmem_alloc(subsec->dofs_size, KM_SLEEP);
11788 bcopy((char *)(uintptr_t)(daddr + subsec->dofs_offset),
11789 *bufp, subsec->dofs_size);
11790
11791 if (subsec->dofs_entsize != 0)
11792 *lenp /= subsec->dofs_entsize;
11793
11794 break;
11795 }
11796
11797 /*
11798 * If we encounter a loadable DIFO sub-section that is not
11799 * known to us, assume this is a broken program and fail.
11800 */
11801 if (difo[i].section == DOF_SECT_NONE &&
11802 (subsec->dofs_flags & DOF_SECF_LOAD)) {
11803 dtrace_dof_error(dof, "unrecognized DIFO subsection");
11804 goto err;
11805 }
11806 }
11807
11808 if (dp->dtdo_buf == NULL) {
11809 /*
11810 * We can't have a DIF object without DIF text.
11811 */
11812 dtrace_dof_error(dof, "missing DIF text");
11813 goto err;
11814 }
11815
11816 /*
11817 * Before we validate the DIF object, run through the variable table
11818 * looking for the strings -- if any of their size are under, we'll set
11819 * their size to be the system-wide default string size. Note that
11820 * this should _not_ happen if the "strsize" option has been set --
11821 * in this case, the compiler should have set the size to reflect the
11822 * setting of the option.
11823 */
11824 for (i = 0; i < dp->dtdo_varlen; i++) {
11825 dtrace_difv_t *v = &dp->dtdo_vartab[i];
11826 dtrace_diftype_t *t = &v->dtdv_type;
11827
11828 if (v->dtdv_id < DIF_VAR_OTHER_UBASE)
11829 continue;
11830
11831 if (t->dtdt_kind == DIF_TYPE_STRING && t->dtdt_size == 0)
11832 t->dtdt_size = dtrace_strsize_default;
11833 }
11834
11835 if (dtrace_difo_validate(dp, vstate, DIF_DIR_NREGS, cr) != 0)
11836 goto err;
11837
11838 dtrace_difo_init(dp, vstate);
11839 return (dp);
11840
11841 err:
11842 kmem_free(dp->dtdo_buf, dp->dtdo_len * sizeof (dif_instr_t));
11843 kmem_free(dp->dtdo_inttab, dp->dtdo_intlen * sizeof (uint64_t));
11844 kmem_free(dp->dtdo_strtab, dp->dtdo_strlen);
11845 kmem_free(dp->dtdo_vartab, dp->dtdo_varlen * sizeof (dtrace_difv_t));
11846
11847 kmem_free(dp, sizeof (dtrace_difo_t));
11848 return (NULL);
11849 }
11850
11851 static dtrace_predicate_t *
11852 dtrace_dof_predicate(dof_hdr_t *dof, dof_sec_t *sec, dtrace_vstate_t *vstate,
11853 cred_t *cr)
11854 {
11855 dtrace_difo_t *dp;
11856
11857 if ((dp = dtrace_dof_difo(dof, sec, vstate, cr)) == NULL)
11858 return (NULL);
11859
11860 return (dtrace_predicate_create(dp));
11861 }
11862
11863 static dtrace_actdesc_t *
11864 dtrace_dof_actdesc(dof_hdr_t *dof, dof_sec_t *sec, dtrace_vstate_t *vstate,
11865 cred_t *cr)
11866 {
11867 dtrace_actdesc_t *act, *first = NULL, *last = NULL, *next;
11868 dof_actdesc_t *desc;
11869 dof_sec_t *difosec;
11870 size_t offs;
11871 uintptr_t daddr = (uintptr_t)dof;
11872 uint64_t arg;
11873 dtrace_actkind_t kind;
11874
11875 if (sec->dofs_type != DOF_SECT_ACTDESC) {
11876 dtrace_dof_error(dof, "invalid action section");
11877 return (NULL);
11878 }
11879
11880 if (sec->dofs_offset + sizeof (dof_actdesc_t) > dof->dofh_loadsz) {
11881 dtrace_dof_error(dof, "truncated action description");
11882 return (NULL);
11883 }
11884
11885 if (sec->dofs_align != sizeof (uint64_t)) {
11886 dtrace_dof_error(dof, "bad alignment in action description");
11887 return (NULL);
11888 }
11889
11890 if (sec->dofs_size < sec->dofs_entsize) {
11891 dtrace_dof_error(dof, "section entry size exceeds total size");
11892 return (NULL);
11893 }
11894
11895 if (sec->dofs_entsize != sizeof (dof_actdesc_t)) {
11896 dtrace_dof_error(dof, "bad entry size in action description");
11897 return (NULL);
11898 }
11899
11900 if (sec->dofs_size / sec->dofs_entsize > dtrace_actions_max) {
11901 dtrace_dof_error(dof, "actions exceed dtrace_actions_max");
11902 return (NULL);
11903 }
11904
11905 for (offs = 0; offs < sec->dofs_size; offs += sec->dofs_entsize) {
11906 desc = (dof_actdesc_t *)(daddr +
11907 (uintptr_t)sec->dofs_offset + offs);
11908 kind = (dtrace_actkind_t)desc->dofa_kind;
11909
11910 if ((DTRACEACT_ISPRINTFLIKE(kind) &&
11911 (kind != DTRACEACT_PRINTA ||
11912 desc->dofa_strtab != DOF_SECIDX_NONE)) ||
11913 (kind == DTRACEACT_DIFEXPR &&
11914 desc->dofa_strtab != DOF_SECIDX_NONE)) {
11915 dof_sec_t *strtab;
11916 char *str, *fmt;
11917 uint64_t i;
11918
11919 /*
11920 * The argument to these actions is an index into the
11921 * DOF string table. For printf()-like actions, this
11922 * is the format string. For print(), this is the
11923 * CTF type of the expression result.
11924 */
11925 if ((strtab = dtrace_dof_sect(dof,
11926 DOF_SECT_STRTAB, desc->dofa_strtab)) == NULL)
11927 goto err;
11928
11929 str = (char *)((uintptr_t)dof +
11930 (uintptr_t)strtab->dofs_offset);
11931
11932 for (i = desc->dofa_arg; i < strtab->dofs_size; i++) {
11933 if (str[i] == '\0')
11934 break;
11935 }
11936
11937 if (i >= strtab->dofs_size) {
11938 dtrace_dof_error(dof, "bogus format string");
11939 goto err;
11940 }
11941
11942 if (i == desc->dofa_arg) {
11943 dtrace_dof_error(dof, "empty format string");
11944 goto err;
11945 }
11946
11947 i -= desc->dofa_arg;
11948 fmt = kmem_alloc(i + 1, KM_SLEEP);
11949 bcopy(&str[desc->dofa_arg], fmt, i + 1);
11950 arg = (uint64_t)(uintptr_t)fmt;
11951 } else {
11952 if (kind == DTRACEACT_PRINTA) {
11953 ASSERT(desc->dofa_strtab == DOF_SECIDX_NONE);
11954 arg = 0;
11955 } else {
11956 arg = desc->dofa_arg;
11957 }
11958 }
11959
11960 act = dtrace_actdesc_create(kind, desc->dofa_ntuple,
11961 desc->dofa_uarg, arg);
11962
11963 if (last != NULL) {
11964 last->dtad_next = act;
11965 } else {
11966 first = act;
11967 }
11968
11969 last = act;
11970
11971 if (desc->dofa_difo == DOF_SECIDX_NONE)
11972 continue;
11973
11974 if ((difosec = dtrace_dof_sect(dof,
11975 DOF_SECT_DIFOHDR, desc->dofa_difo)) == NULL)
11976 goto err;
11977
11978 act->dtad_difo = dtrace_dof_difo(dof, difosec, vstate, cr);
11979
11980 if (act->dtad_difo == NULL)
11981 goto err;
11982 }
11983
11984 ASSERT(first != NULL);
11985 return (first);
11986
11987 err:
11988 for (act = first; act != NULL; act = next) {
11989 next = act->dtad_next;
11990 dtrace_actdesc_release(act, vstate);
11991 }
11992
11993 return (NULL);
11994 }
11995
11996 static dtrace_ecbdesc_t *
11997 dtrace_dof_ecbdesc(dof_hdr_t *dof, dof_sec_t *sec, dtrace_vstate_t *vstate,
11998 cred_t *cr)
11999 {
12000 dtrace_ecbdesc_t *ep;
12001 dof_ecbdesc_t *ecb;
12002 dtrace_probedesc_t *desc;
12003 dtrace_predicate_t *pred = NULL;
12004
12005 if (sec->dofs_size < sizeof (dof_ecbdesc_t)) {
12006 dtrace_dof_error(dof, "truncated ECB description");
12007 return (NULL);
12008 }
12009
12010 if (sec->dofs_align != sizeof (uint64_t)) {
12011 dtrace_dof_error(dof, "bad alignment in ECB description");
12012 return (NULL);
12013 }
12014
12015 ecb = (dof_ecbdesc_t *)((uintptr_t)dof + (uintptr_t)sec->dofs_offset);
12016 sec = dtrace_dof_sect(dof, DOF_SECT_PROBEDESC, ecb->dofe_probes);
12017
12018 if (sec == NULL)
12019 return (NULL);
12020
12021 ep = kmem_zalloc(sizeof (dtrace_ecbdesc_t), KM_SLEEP);
12022 ep->dted_uarg = ecb->dofe_uarg;
12023 desc = &ep->dted_probe;
12024
12025 if (dtrace_dof_probedesc(dof, sec, desc) == NULL)
12026 goto err;
12027
12028 if (ecb->dofe_pred != DOF_SECIDX_NONE) {
12029 if ((sec = dtrace_dof_sect(dof,
12030 DOF_SECT_DIFOHDR, ecb->dofe_pred)) == NULL)
12031 goto err;
12032
12033 if ((pred = dtrace_dof_predicate(dof, sec, vstate, cr)) == NULL)
12034 goto err;
12035
12036 ep->dted_pred.dtpdd_predicate = pred;
12037 }
12038
12039 if (ecb->dofe_actions != DOF_SECIDX_NONE) {
12040 if ((sec = dtrace_dof_sect(dof,
12041 DOF_SECT_ACTDESC, ecb->dofe_actions)) == NULL)
12042 goto err;
12043
12044 ep->dted_action = dtrace_dof_actdesc(dof, sec, vstate, cr);
12045
12046 if (ep->dted_action == NULL)
12047 goto err;
12048 }
12049
12050 return (ep);
12051
12052 err:
12053 if (pred != NULL)
12054 dtrace_predicate_release(pred, vstate);
12055 kmem_free(ep, sizeof (dtrace_ecbdesc_t));
12056 return (NULL);
12057 }
12058
12059 /*
12060 * Apply the relocations from the specified 'sec' (a DOF_SECT_URELHDR) to the
12061 * specified DOF. At present, this amounts to simply adding 'ubase' to the
12062 * site of any user SETX relocations to account for load object base address.
12063 * In the future, if we need other relocations, this function can be extended.
12064 */
12065 static int
12066 dtrace_dof_relocate(dof_hdr_t *dof, dof_sec_t *sec, uint64_t ubase)
12067 {
12068 uintptr_t daddr = (uintptr_t)dof;
12069 dof_relohdr_t *dofr =
12070 (dof_relohdr_t *)(uintptr_t)(daddr + sec->dofs_offset);
12071 dof_sec_t *ss, *rs, *ts;
12072 dof_relodesc_t *r;
12073 uint_t i, n;
12074
12075 if (sec->dofs_size < sizeof (dof_relohdr_t) ||
12076 sec->dofs_align != sizeof (dof_secidx_t)) {
12077 dtrace_dof_error(dof, "invalid relocation header");
12078 return (-1);
12079 }
12080
12081 ss = dtrace_dof_sect(dof, DOF_SECT_STRTAB, dofr->dofr_strtab);
12082 rs = dtrace_dof_sect(dof, DOF_SECT_RELTAB, dofr->dofr_relsec);
12083 ts = dtrace_dof_sect(dof, DOF_SECT_NONE, dofr->dofr_tgtsec);
12084
12085 if (ss == NULL || rs == NULL || ts == NULL)
12086 return (-1); /* dtrace_dof_error() has been called already */
12087
12088 if (rs->dofs_entsize < sizeof (dof_relodesc_t) ||
12089 rs->dofs_align != sizeof (uint64_t)) {
12090 dtrace_dof_error(dof, "invalid relocation section");
12091 return (-1);
12092 }
12093
12094 r = (dof_relodesc_t *)(uintptr_t)(daddr + rs->dofs_offset);
12095 n = rs->dofs_size / rs->dofs_entsize;
12096
12097 for (i = 0; i < n; i++) {
12098 uintptr_t taddr = daddr + ts->dofs_offset + r->dofr_offset;
12099
12100 switch (r->dofr_type) {
12101 case DOF_RELO_NONE:
12102 break;
12103 case DOF_RELO_SETX:
12104 if (r->dofr_offset >= ts->dofs_size || r->dofr_offset +
12105 sizeof (uint64_t) > ts->dofs_size) {
12106 dtrace_dof_error(dof, "bad relocation offset");
12107 return (-1);
12108 }
12109
12110 if (!IS_P2ALIGNED(taddr, sizeof (uint64_t))) {
12111 dtrace_dof_error(dof, "misaligned setx relo");
12112 return (-1);
12113 }
12114
12115 *(uint64_t *)taddr += ubase;
12116 break;
12117 default:
12118 dtrace_dof_error(dof, "invalid relocation type");
12119 return (-1);
12120 }
12121
12122 r = (dof_relodesc_t *)((uintptr_t)r + rs->dofs_entsize);
12123 }
12124
12125 return (0);
12126 }
12127
12128 /*
12129 * The dof_hdr_t passed to dtrace_dof_slurp() should be a partially validated
12130 * header: it should be at the front of a memory region that is at least
12131 * sizeof (dof_hdr_t) in size -- and then at least dof_hdr.dofh_loadsz in
12132 * size. It need not be validated in any other way.
12133 */
12134 static int
12135 dtrace_dof_slurp(dof_hdr_t *dof, dtrace_vstate_t *vstate, cred_t *cr,
12136 dtrace_enabling_t **enabp, uint64_t ubase, int noprobes)
12137 {
12138 uint64_t len = dof->dofh_loadsz, seclen;
12139 uintptr_t daddr = (uintptr_t)dof;
12140 dtrace_ecbdesc_t *ep;
12141 dtrace_enabling_t *enab;
12142 uint_t i;
12143
12144 ASSERT(MUTEX_HELD(&dtrace_lock));
12145 ASSERT(dof->dofh_loadsz >= sizeof (dof_hdr_t));
12146
12147 /*
12148 * Check the DOF header identification bytes. In addition to checking
12149 * valid settings, we also verify that unused bits/bytes are zeroed so
12150 * we can use them later without fear of regressing existing binaries.
12151 */
12152 if (bcmp(&dof->dofh_ident[DOF_ID_MAG0],
12153 DOF_MAG_STRING, DOF_MAG_STRLEN) != 0) {
12154 dtrace_dof_error(dof, "DOF magic string mismatch");
12155 return (-1);
12156 }
12157
12158 if (dof->dofh_ident[DOF_ID_MODEL] != DOF_MODEL_ILP32 &&
12159 dof->dofh_ident[DOF_ID_MODEL] != DOF_MODEL_LP64) {
12160 dtrace_dof_error(dof, "DOF has invalid data model");
12161 return (-1);
12162 }
12163
12164 if (dof->dofh_ident[DOF_ID_ENCODING] != DOF_ENCODE_NATIVE) {
12165 dtrace_dof_error(dof, "DOF encoding mismatch");
12166 return (-1);
12167 }
12168
12169 if (dof->dofh_ident[DOF_ID_VERSION] != DOF_VERSION_1 &&
12170 dof->dofh_ident[DOF_ID_VERSION] != DOF_VERSION_2) {
12171 dtrace_dof_error(dof, "DOF version mismatch");
12172 return (-1);
12173 }
12174
12175 if (dof->dofh_ident[DOF_ID_DIFVERS] != DIF_VERSION_2) {
12176 dtrace_dof_error(dof, "DOF uses unsupported instruction set");
12177 return (-1);
12178 }
12179
12180 if (dof->dofh_ident[DOF_ID_DIFIREG] > DIF_DIR_NREGS) {
12181 dtrace_dof_error(dof, "DOF uses too many integer registers");
12182 return (-1);
12183 }
12184
12185 if (dof->dofh_ident[DOF_ID_DIFTREG] > DIF_DTR_NREGS) {
12186 dtrace_dof_error(dof, "DOF uses too many tuple registers");
12187 return (-1);
12188 }
12189
12190 for (i = DOF_ID_PAD; i < DOF_ID_SIZE; i++) {
12191 if (dof->dofh_ident[i] != 0) {
12192 dtrace_dof_error(dof, "DOF has invalid ident byte set");
12193 return (-1);
12194 }
12195 }
12196
12197 if (dof->dofh_flags & ~DOF_FL_VALID) {
12198 dtrace_dof_error(dof, "DOF has invalid flag bits set");
12199 return (-1);
12200 }
12201
12202 if (dof->dofh_secsize == 0) {
12203 dtrace_dof_error(dof, "zero section header size");
12204 return (-1);
12205 }
12206
12207 /*
12208 * Check that the section headers don't exceed the amount of DOF
12209 * data. Note that we cast the section size and number of sections
12210 * to uint64_t's to prevent possible overflow in the multiplication.
12211 */
12212 seclen = (uint64_t)dof->dofh_secnum * (uint64_t)dof->dofh_secsize;
12213
12214 if (dof->dofh_secoff > len || seclen > len ||
12215 dof->dofh_secoff + seclen > len) {
12216 dtrace_dof_error(dof, "truncated section headers");
12217 return (-1);
12218 }
12219
12220 if (!IS_P2ALIGNED(dof->dofh_secoff, sizeof (uint64_t))) {
12221 dtrace_dof_error(dof, "misaligned section headers");
12222 return (-1);
12223 }
12224
12225 if (!IS_P2ALIGNED(dof->dofh_secsize, sizeof (uint64_t))) {
12226 dtrace_dof_error(dof, "misaligned section size");
12227 return (-1);
12228 }
12229
12230 /*
12231 * Take an initial pass through the section headers to be sure that
12232 * the headers don't have stray offsets. If the 'noprobes' flag is
12233 * set, do not permit sections relating to providers, probes, or args.
12234 */
12235 for (i = 0; i < dof->dofh_secnum; i++) {
12236 dof_sec_t *sec = (dof_sec_t *)(daddr +
12237 (uintptr_t)dof->dofh_secoff + i * dof->dofh_secsize);
12238
12239 if (noprobes) {
12240 switch (sec->dofs_type) {
12241 case DOF_SECT_PROVIDER:
12242 case DOF_SECT_PROBES:
12243 case DOF_SECT_PRARGS:
12244 case DOF_SECT_PROFFS:
12245 dtrace_dof_error(dof, "illegal sections "
12246 "for enabling");
12247 return (-1);
12248 }
12249 }
12250
12251 if (DOF_SEC_ISLOADABLE(sec->dofs_type) &&
12252 !(sec->dofs_flags & DOF_SECF_LOAD)) {
12253 dtrace_dof_error(dof, "loadable section with load "
12254 "flag unset");
12255 return (-1);
12256 }
12257
12258 if (!(sec->dofs_flags & DOF_SECF_LOAD))
12259 continue; /* just ignore non-loadable sections */
12260
12261 if (sec->dofs_align & (sec->dofs_align - 1)) {
12262 dtrace_dof_error(dof, "bad section alignment");
12263 return (-1);
12264 }
12265
12266 if (sec->dofs_offset & (sec->dofs_align - 1)) {
12267 dtrace_dof_error(dof, "misaligned section");
12268 return (-1);
12269 }
12270
12271 if (sec->dofs_offset > len || sec->dofs_size > len ||
12272 sec->dofs_offset + sec->dofs_size > len) {
12273 dtrace_dof_error(dof, "corrupt section header");
12274 return (-1);
12275 }
12276
12277 if (sec->dofs_type == DOF_SECT_STRTAB && *((char *)daddr +
12278 sec->dofs_offset + sec->dofs_size - 1) != '\0') {
12279 dtrace_dof_error(dof, "non-terminating string table");
12280 return (-1);
12281 }
12282 }
12283
12284 /*
12285 * Take a second pass through the sections and locate and perform any
12286 * relocations that are present. We do this after the first pass to
12287 * be sure that all sections have had their headers validated.
12288 */
12289 for (i = 0; i < dof->dofh_secnum; i++) {
12290 dof_sec_t *sec = (dof_sec_t *)(daddr +
12291 (uintptr_t)dof->dofh_secoff + i * dof->dofh_secsize);
12292
12293 if (!(sec->dofs_flags & DOF_SECF_LOAD))
12294 continue; /* skip sections that are not loadable */
12295
12296 switch (sec->dofs_type) {
12297 case DOF_SECT_URELHDR:
12298 if (dtrace_dof_relocate(dof, sec, ubase) != 0)
12299 return (-1);
12300 break;
12301 }
12302 }
12303
12304 if ((enab = *enabp) == NULL)
12305 enab = *enabp = dtrace_enabling_create(vstate);
12306
12307 for (i = 0; i < dof->dofh_secnum; i++) {
12308 dof_sec_t *sec = (dof_sec_t *)(daddr +
12309 (uintptr_t)dof->dofh_secoff + i * dof->dofh_secsize);
12310
12311 if (sec->dofs_type != DOF_SECT_ECBDESC)
12312 continue;
12313
12314 if ((ep = dtrace_dof_ecbdesc(dof, sec, vstate, cr)) == NULL) {
12315 dtrace_enabling_destroy(enab);
12316 *enabp = NULL;
12317 return (-1);
12318 }
12319
12320 dtrace_enabling_add(enab, ep);
12321 }
12322
12323 return (0);
12324 }
12325
12326 /*
12327 * Process DOF for any options. This routine assumes that the DOF has been
12328 * at least processed by dtrace_dof_slurp().
12329 */
12330 static int
12331 dtrace_dof_options(dof_hdr_t *dof, dtrace_state_t *state)
12332 {
12333 int i, rval;
12334 uint32_t entsize;
12335 size_t offs;
12336 dof_optdesc_t *desc;
12337
12338 for (i = 0; i < dof->dofh_secnum; i++) {
12339 dof_sec_t *sec = (dof_sec_t *)((uintptr_t)dof +
12340 (uintptr_t)dof->dofh_secoff + i * dof->dofh_secsize);
12341
12342 if (sec->dofs_type != DOF_SECT_OPTDESC)
12343 continue;
12344
12345 if (sec->dofs_align != sizeof (uint64_t)) {
12346 dtrace_dof_error(dof, "bad alignment in "
12347 "option description");
12348 return (EINVAL);
12349 }
12350
12351 if ((entsize = sec->dofs_entsize) == 0) {
12352 dtrace_dof_error(dof, "zeroed option entry size");
12353 return (EINVAL);
12354 }
12355
12356 if (entsize < sizeof (dof_optdesc_t)) {
12357 dtrace_dof_error(dof, "bad option entry size");
12358 return (EINVAL);
12359 }
12360
12361 for (offs = 0; offs < sec->dofs_size; offs += entsize) {
12362 desc = (dof_optdesc_t *)((uintptr_t)dof +
12363 (uintptr_t)sec->dofs_offset + offs);
12364
12365 if (desc->dofo_strtab != DOF_SECIDX_NONE) {
12366 dtrace_dof_error(dof, "non-zero option string");
12367 return (EINVAL);
12368 }
12369
12370 if (desc->dofo_value == DTRACEOPT_UNSET) {
12371 dtrace_dof_error(dof, "unset option");
12372 return (EINVAL);
12373 }
12374
12375 if ((rval = dtrace_state_option(state,
12376 desc->dofo_option, desc->dofo_value)) != 0) {
12377 dtrace_dof_error(dof, "rejected option");
12378 return (rval);
12379 }
12380 }
12381 }
12382
12383 return (0);
12384 }
12385
12386 /*
12387 * DTrace Consumer State Functions
12388 */
12389 int
12390 dtrace_dstate_init(dtrace_dstate_t *dstate, size_t size)
12391 {
12392 size_t hashsize, maxper, min, chunksize = dstate->dtds_chunksize;
12393 void *base;
12394 uintptr_t limit;
12395 dtrace_dynvar_t *dvar, *next, *start;
12396 int i;
12397
12398 ASSERT(MUTEX_HELD(&dtrace_lock));
12399 ASSERT(dstate->dtds_base == NULL && dstate->dtds_percpu == NULL);
12400
12401 bzero(dstate, sizeof (dtrace_dstate_t));
12402
12403 if ((dstate->dtds_chunksize = chunksize) == 0)
12404 dstate->dtds_chunksize = DTRACE_DYNVAR_CHUNKSIZE;
12405
12406 if (size < (min = dstate->dtds_chunksize + sizeof (dtrace_dynhash_t)))
12407 size = min;
12408
12409 if ((base = kmem_zalloc(size, KM_NOSLEEP | KM_NORMALPRI)) == NULL)
12410 return (ENOMEM);
12411
12412 dstate->dtds_size = size;
12413 dstate->dtds_base = base;
12414 dstate->dtds_percpu = kmem_cache_alloc(dtrace_state_cache, KM_SLEEP);
12415 bzero(dstate->dtds_percpu, NCPU * sizeof (dtrace_dstate_percpu_t));
12416
12417 hashsize = size / (dstate->dtds_chunksize + sizeof (dtrace_dynhash_t));
12418
12419 if (hashsize != 1 && (hashsize & 1))
12420 hashsize--;
12421
12422 dstate->dtds_hashsize = hashsize;
12423 dstate->dtds_hash = dstate->dtds_base;
12424
12425 /*
12426 * Set all of our hash buckets to point to the single sink, and (if
12427 * it hasn't already been set), set the sink's hash value to be the
12428 * sink sentinel value. The sink is needed for dynamic variable
12429 * lookups to know that they have iterated over an entire, valid hash
12430 * chain.
12431 */
12432 for (i = 0; i < hashsize; i++)
12433 dstate->dtds_hash[i].dtdh_chain = &dtrace_dynhash_sink;
12434
12435 if (dtrace_dynhash_sink.dtdv_hashval != DTRACE_DYNHASH_SINK)
12436 dtrace_dynhash_sink.dtdv_hashval = DTRACE_DYNHASH_SINK;
12437
12438 /*
12439 * Determine number of active CPUs. Divide free list evenly among
12440 * active CPUs.
12441 */
12442 start = (dtrace_dynvar_t *)
12443 ((uintptr_t)base + hashsize * sizeof (dtrace_dynhash_t));
12444 limit = (uintptr_t)base + size;
12445
12446 maxper = (limit - (uintptr_t)start) / NCPU;
12447 maxper = (maxper / dstate->dtds_chunksize) * dstate->dtds_chunksize;
12448
12449 for (i = 0; i < NCPU; i++) {
12450 dstate->dtds_percpu[i].dtdsc_free = dvar = start;
12451
12452 /*
12453 * If we don't even have enough chunks to make it once through
12454 * NCPUs, we're just going to allocate everything to the first
12455 * CPU. And if we're on the last CPU, we're going to allocate
12456 * whatever is left over. In either case, we set the limit to
12457 * be the limit of the dynamic variable space.
12458 */
12459 if (maxper == 0 || i == NCPU - 1) {
12460 limit = (uintptr_t)base + size;
12461 start = NULL;
12462 } else {
12463 limit = (uintptr_t)start + maxper;
12464 start = (dtrace_dynvar_t *)limit;
12465 }
12466
12467 ASSERT(limit <= (uintptr_t)base + size);
12468
12469 for (;;) {
12470 next = (dtrace_dynvar_t *)((uintptr_t)dvar +
12471 dstate->dtds_chunksize);
12472
12473 if ((uintptr_t)next + dstate->dtds_chunksize >= limit)
12474 break;
12475
12476 dvar->dtdv_next = next;
12477 dvar = next;
12478 }
12479
12480 if (maxper == 0)
12481 break;
12482 }
12483
12484 return (0);
12485 }
12486
12487 void
12488 dtrace_dstate_fini(dtrace_dstate_t *dstate)
12489 {
12490 ASSERT(MUTEX_HELD(&cpu_lock));
12491
12492 if (dstate->dtds_base == NULL)
12493 return;
12494
12495 kmem_free(dstate->dtds_base, dstate->dtds_size);
12496 kmem_cache_free(dtrace_state_cache, dstate->dtds_percpu);
12497 }
12498
12499 static void
12500 dtrace_vstate_fini(dtrace_vstate_t *vstate)
12501 {
12502 /*
12503 * Logical XOR, where are you?
12504 */
12505 ASSERT((vstate->dtvs_nglobals == 0) ^ (vstate->dtvs_globals != NULL));
12506
12507 if (vstate->dtvs_nglobals > 0) {
12508 kmem_free(vstate->dtvs_globals, vstate->dtvs_nglobals *
12509 sizeof (dtrace_statvar_t *));
12510 }
12511
12512 if (vstate->dtvs_ntlocals > 0) {
12513 kmem_free(vstate->dtvs_tlocals, vstate->dtvs_ntlocals *
12514 sizeof (dtrace_difv_t));
12515 }
12516
12517 ASSERT((vstate->dtvs_nlocals == 0) ^ (vstate->dtvs_locals != NULL));
12518
12519 if (vstate->dtvs_nlocals > 0) {
12520 kmem_free(vstate->dtvs_locals, vstate->dtvs_nlocals *
12521 sizeof (dtrace_statvar_t *));
12522 }
12523 }
12524
12525 static void
12526 dtrace_state_clean(dtrace_state_t *state)
12527 {
12528 if (state->dts_activity == DTRACE_ACTIVITY_INACTIVE)
12529 return;
12530
12531 dtrace_dynvar_clean(&state->dts_vstate.dtvs_dynvars);
12532 dtrace_speculation_clean(state);
12533 }
12534
12535 static void
12536 dtrace_state_deadman(dtrace_state_t *state)
12537 {
12538 hrtime_t now;
12539
12540 dtrace_sync();
12541
12542 now = dtrace_gethrtime();
12543
12544 if (state != dtrace_anon.dta_state &&
12545 now - state->dts_laststatus >= dtrace_deadman_user)
12546 return;
12547
12548 /*
12549 * We must be sure that dts_alive never appears to be less than the
12550 * value upon entry to dtrace_state_deadman(), and because we lack a
12551 * dtrace_cas64(), we cannot store to it atomically. We thus instead
12552 * store INT64_MAX to it, followed by a memory barrier, followed by
12553 * the new value. This assures that dts_alive never appears to be
12554 * less than its true value, regardless of the order in which the
12555 * stores to the underlying storage are issued.
12556 */
12557 state->dts_alive = INT64_MAX;
12558 dtrace_membar_producer();
12559 state->dts_alive = now;
12560 }
12561
12562 dtrace_state_t *
12563 dtrace_state_create(dev_t *devp, cred_t *cr)
12564 {
12565 minor_t minor;
12566 major_t major;
12567 char c[30];
12568 dtrace_state_t *state;
12569 dtrace_optval_t *opt;
12570 int bufsize = NCPU * sizeof (dtrace_buffer_t), i;
12571
12572 ASSERT(MUTEX_HELD(&dtrace_lock));
12573 ASSERT(MUTEX_HELD(&cpu_lock));
12574
12575 minor = (minor_t)(uintptr_t)vmem_alloc(dtrace_minor, 1,
12576 VM_BESTFIT | VM_SLEEP);
12577
12578 if (ddi_soft_state_zalloc(dtrace_softstate, minor) != DDI_SUCCESS) {
12579 vmem_free(dtrace_minor, (void *)(uintptr_t)minor, 1);
12580 return (NULL);
12581 }
12582
12583 state = ddi_get_soft_state(dtrace_softstate, minor);
12584 state->dts_epid = DTRACE_EPIDNONE + 1;
12585
12586 (void) snprintf(c, sizeof (c), "dtrace_aggid_%d", minor);
12587 state->dts_aggid_arena = vmem_create(c, (void *)1, UINT32_MAX, 1,
12588 NULL, NULL, NULL, 0, VM_SLEEP | VMC_IDENTIFIER);
12589
12590 if (devp != NULL) {
12591 major = getemajor(*devp);
12592 } else {
12593 major = ddi_driver_major(dtrace_devi);
12594 }
12595
12596 state->dts_dev = makedevice(major, minor);
12597
12598 if (devp != NULL)
12599 *devp = state->dts_dev;
12600
12601 /*
12602 * We allocate NCPU buffers. On the one hand, this can be quite
12603 * a bit of memory per instance (nearly 36K on a Starcat). On the
12604 * other hand, it saves an additional memory reference in the probe
12605 * path.
12606 */
12607 state->dts_buffer = kmem_zalloc(bufsize, KM_SLEEP);
12608 state->dts_aggbuffer = kmem_zalloc(bufsize, KM_SLEEP);
12609 state->dts_cleaner = CYCLIC_NONE;
12610 state->dts_deadman = CYCLIC_NONE;
12611 state->dts_vstate.dtvs_state = state;
12612
12613 for (i = 0; i < DTRACEOPT_MAX; i++)
12614 state->dts_options[i] = DTRACEOPT_UNSET;
12615
12616 /*
12617 * Set the default options.
12618 */
12619 opt = state->dts_options;
12620 opt[DTRACEOPT_BUFPOLICY] = DTRACEOPT_BUFPOLICY_SWITCH;
12621 opt[DTRACEOPT_BUFRESIZE] = DTRACEOPT_BUFRESIZE_AUTO;
12622 opt[DTRACEOPT_NSPEC] = dtrace_nspec_default;
12623 opt[DTRACEOPT_SPECSIZE] = dtrace_specsize_default;
12624 opt[DTRACEOPT_CPU] = (dtrace_optval_t)DTRACE_CPUALL;
12625 opt[DTRACEOPT_STRSIZE] = dtrace_strsize_default;
12626 opt[DTRACEOPT_STACKFRAMES] = dtrace_stackframes_default;
12627 opt[DTRACEOPT_USTACKFRAMES] = dtrace_ustackframes_default;
12628 opt[DTRACEOPT_CLEANRATE] = dtrace_cleanrate_default;
12629 opt[DTRACEOPT_AGGRATE] = dtrace_aggrate_default;
12630 opt[DTRACEOPT_SWITCHRATE] = dtrace_switchrate_default;
12631 opt[DTRACEOPT_STATUSRATE] = dtrace_statusrate_default;
12632 opt[DTRACEOPT_JSTACKFRAMES] = dtrace_jstackframes_default;
12633 opt[DTRACEOPT_JSTACKSTRSIZE] = dtrace_jstackstrsize_default;
12634
12635 state->dts_activity = DTRACE_ACTIVITY_INACTIVE;
12636
12637 /*
12638 * Depending on the user credentials, we set flag bits which alter probe
12639 * visibility or the amount of destructiveness allowed. In the case of
12640 * actual anonymous tracing, or the possession of all privileges, all of
12641 * the normal checks are bypassed.
12642 */
12643 if (cr == NULL || PRIV_POLICY_ONLY(cr, PRIV_ALL, B_FALSE)) {
12644 state->dts_cred.dcr_visible = DTRACE_CRV_ALL;
12645 state->dts_cred.dcr_action = DTRACE_CRA_ALL;
12646 } else {
12647 /*
12648 * Set up the credentials for this instantiation. We take a
12649 * hold on the credential to prevent it from disappearing on
12650 * us; this in turn prevents the zone_t referenced by this
12651 * credential from disappearing. This means that we can
12652 * examine the credential and the zone from probe context.
12653 */
12654 crhold(cr);
12655 state->dts_cred.dcr_cred = cr;
12656
12657 /*
12658 * CRA_PROC means "we have *some* privilege for dtrace" and
12659 * unlocks the use of variables like pid, zonename, etc.
12660 */
12661 if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_USER, B_FALSE) ||
12662 PRIV_POLICY_ONLY(cr, PRIV_DTRACE_PROC, B_FALSE)) {
12663 state->dts_cred.dcr_action |= DTRACE_CRA_PROC;
12664 }
12665
12666 /*
12667 * dtrace_user allows use of syscall and profile providers.
12668 * If the user also has proc_owner and/or proc_zone, we
12669 * extend the scope to include additional visibility and
12670 * destructive power.
12671 */
12672 if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_USER, B_FALSE)) {
12673 if (PRIV_POLICY_ONLY(cr, PRIV_PROC_OWNER, B_FALSE)) {
12674 state->dts_cred.dcr_visible |=
12675 DTRACE_CRV_ALLPROC;
12676
12677 state->dts_cred.dcr_action |=
12678 DTRACE_CRA_PROC_DESTRUCTIVE_ALLUSER;
12679 }
12680
12681 if (PRIV_POLICY_ONLY(cr, PRIV_PROC_ZONE, B_FALSE)) {
12682 state->dts_cred.dcr_visible |=
12683 DTRACE_CRV_ALLZONE;
12684
12685 state->dts_cred.dcr_action |=
12686 DTRACE_CRA_PROC_DESTRUCTIVE_ALLZONE;
12687 }
12688
12689 /*
12690 * If we have all privs in whatever zone this is,
12691 * we can do destructive things to processes which
12692 * have altered credentials.
12693 */
12694 if (priv_isequalset(priv_getset(cr, PRIV_EFFECTIVE),
12695 cr->cr_zone->zone_privset)) {
12696 state->dts_cred.dcr_action |=
12697 DTRACE_CRA_PROC_DESTRUCTIVE_CREDCHG;
12698 }
12699 }
12700
12701 /*
12702 * Holding the dtrace_kernel privilege also implies that
12703 * the user has the dtrace_user privilege from a visibility
12704 * perspective. But without further privileges, some
12705 * destructive actions are not available.
12706 */
12707 if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_KERNEL, B_FALSE)) {
12708 /*
12709 * Make all probes in all zones visible. However,
12710 * this doesn't mean that all actions become available
12711 * to all zones.
12712 */
12713 state->dts_cred.dcr_visible |= DTRACE_CRV_KERNEL |
12714 DTRACE_CRV_ALLPROC | DTRACE_CRV_ALLZONE;
12715
12716 state->dts_cred.dcr_action |= DTRACE_CRA_KERNEL |
12717 DTRACE_CRA_PROC;
12718 /*
12719 * Holding proc_owner means that destructive actions
12720 * for *this* zone are allowed.
12721 */
12722 if (PRIV_POLICY_ONLY(cr, PRIV_PROC_OWNER, B_FALSE))
12723 state->dts_cred.dcr_action |=
12724 DTRACE_CRA_PROC_DESTRUCTIVE_ALLUSER;
12725
12726 /*
12727 * Holding proc_zone means that destructive actions
12728 * for this user/group ID in all zones is allowed.
12729 */
12730 if (PRIV_POLICY_ONLY(cr, PRIV_PROC_ZONE, B_FALSE))
12731 state->dts_cred.dcr_action |=
12732 DTRACE_CRA_PROC_DESTRUCTIVE_ALLZONE;
12733
12734 /*
12735 * If we have all privs in whatever zone this is,
12736 * we can do destructive things to processes which
12737 * have altered credentials.
12738 */
12739 if (priv_isequalset(priv_getset(cr, PRIV_EFFECTIVE),
12740 cr->cr_zone->zone_privset)) {
12741 state->dts_cred.dcr_action |=
12742 DTRACE_CRA_PROC_DESTRUCTIVE_CREDCHG;
12743 }
12744 }
12745
12746 /*
12747 * Holding the dtrace_proc privilege gives control over fasttrap
12748 * and pid providers. We need to grant wider destructive
12749 * privileges in the event that the user has proc_owner and/or
12750 * proc_zone.
12751 */
12752 if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_PROC, B_FALSE)) {
12753 if (PRIV_POLICY_ONLY(cr, PRIV_PROC_OWNER, B_FALSE))
12754 state->dts_cred.dcr_action |=
12755 DTRACE_CRA_PROC_DESTRUCTIVE_ALLUSER;
12756
12757 if (PRIV_POLICY_ONLY(cr, PRIV_PROC_ZONE, B_FALSE))
12758 state->dts_cred.dcr_action |=
12759 DTRACE_CRA_PROC_DESTRUCTIVE_ALLZONE;
12760 }
12761 }
12762
12763 return (state);
12764 }
12765
12766 static int
12767 dtrace_state_buffer(dtrace_state_t *state, dtrace_buffer_t *buf, int which)
12768 {
12769 dtrace_optval_t *opt = state->dts_options, size;
12770 processorid_t cpu;
12771 int flags = 0, rval, factor, divisor = 1;
12772
12773 ASSERT(MUTEX_HELD(&dtrace_lock));
12774 ASSERT(MUTEX_HELD(&cpu_lock));
12775 ASSERT(which < DTRACEOPT_MAX);
12776 ASSERT(state->dts_activity == DTRACE_ACTIVITY_INACTIVE ||
12777 (state == dtrace_anon.dta_state &&
12778 state->dts_activity == DTRACE_ACTIVITY_ACTIVE));
12779
12780 if (opt[which] == DTRACEOPT_UNSET || opt[which] == 0)
12781 return (0);
12782
12783 if (opt[DTRACEOPT_CPU] != DTRACEOPT_UNSET)
12784 cpu = opt[DTRACEOPT_CPU];
12785
12786 if (which == DTRACEOPT_SPECSIZE)
12787 flags |= DTRACEBUF_NOSWITCH;
12788
12789 if (which == DTRACEOPT_BUFSIZE) {
12790 if (opt[DTRACEOPT_BUFPOLICY] == DTRACEOPT_BUFPOLICY_RING)
12791 flags |= DTRACEBUF_RING;
12792
12793 if (opt[DTRACEOPT_BUFPOLICY] == DTRACEOPT_BUFPOLICY_FILL)
12794 flags |= DTRACEBUF_FILL;
12795
12796 if (state != dtrace_anon.dta_state ||
12797 state->dts_activity != DTRACE_ACTIVITY_ACTIVE)
12798 flags |= DTRACEBUF_INACTIVE;
12799 }
12800
12801 for (size = opt[which]; size >= sizeof (uint64_t); size /= divisor) {
12802 /*
12803 * The size must be 8-byte aligned. If the size is not 8-byte
12804 * aligned, drop it down by the difference.
12805 */
12806 if (size & (sizeof (uint64_t) - 1))
12807 size -= size & (sizeof (uint64_t) - 1);
12808
12809 if (size < state->dts_reserve) {
12810 /*
12811 * Buffers always must be large enough to accommodate
12812 * their prereserved space. We return E2BIG instead
12813 * of ENOMEM in this case to allow for user-level
12814 * software to differentiate the cases.
12815 */
12816 return (E2BIG);
12817 }
12818
12819 rval = dtrace_buffer_alloc(buf, size, flags, cpu, &factor);
12820
12821 if (rval != ENOMEM) {
12822 opt[which] = size;
12823 return (rval);
12824 }
12825
12826 if (opt[DTRACEOPT_BUFRESIZE] == DTRACEOPT_BUFRESIZE_MANUAL)
12827 return (rval);
12828
12829 for (divisor = 2; divisor < factor; divisor <<= 1)
12830 continue;
12831 }
12832
12833 return (ENOMEM);
12834 }
12835
12836 static int
12837 dtrace_state_buffers(dtrace_state_t *state)
12838 {
12839 dtrace_speculation_t *spec = state->dts_speculations;
12840 int rval, i;
12841
12842 if ((rval = dtrace_state_buffer(state, state->dts_buffer,
12843 DTRACEOPT_BUFSIZE)) != 0)
12844 return (rval);
12845
12846 if ((rval = dtrace_state_buffer(state, state->dts_aggbuffer,
12847 DTRACEOPT_AGGSIZE)) != 0)
12848 return (rval);
12849
12850 for (i = 0; i < state->dts_nspeculations; i++) {
12851 if ((rval = dtrace_state_buffer(state,
12852 spec[i].dtsp_buffer, DTRACEOPT_SPECSIZE)) != 0)
12853 return (rval);
12854 }
12855
12856 return (0);
12857 }
12858
12859 static void
12860 dtrace_state_prereserve(dtrace_state_t *state)
12861 {
12862 dtrace_ecb_t *ecb;
12863 dtrace_probe_t *probe;
12864
12865 state->dts_reserve = 0;
12866
12867 if (state->dts_options[DTRACEOPT_BUFPOLICY] != DTRACEOPT_BUFPOLICY_FILL)
12868 return;
12869
12870 /*
12871 * If our buffer policy is a "fill" buffer policy, we need to set the
12872 * prereserved space to be the space required by the END probes.
12873 */
12874 probe = dtrace_probes[dtrace_probeid_end - 1];
12875 ASSERT(probe != NULL);
12876
12877 for (ecb = probe->dtpr_ecb; ecb != NULL; ecb = ecb->dte_next) {
12878 if (ecb->dte_state != state)
12879 continue;
12880
12881 state->dts_reserve += ecb->dte_needed + ecb->dte_alignment;
12882 }
12883 }
12884
12885 static int
12886 dtrace_state_go(dtrace_state_t *state, processorid_t *cpu)
12887 {
12888 dtrace_optval_t *opt = state->dts_options, sz, nspec;
12889 dtrace_speculation_t *spec;
12890 dtrace_buffer_t *buf;
12891 cyc_handler_t hdlr;
12892 cyc_time_t when;
12893 int rval = 0, i, bufsize = NCPU * sizeof (dtrace_buffer_t);
12894 dtrace_icookie_t cookie;
12895
12896 mutex_enter(&cpu_lock);
12897 mutex_enter(&dtrace_lock);
12898
12899 if (state->dts_activity != DTRACE_ACTIVITY_INACTIVE) {
12900 rval = EBUSY;
12901 goto out;
12902 }
12903
12904 /*
12905 * Before we can perform any checks, we must prime all of the
12906 * retained enablings that correspond to this state.
12907 */
12908 dtrace_enabling_prime(state);
12909
12910 if (state->dts_destructive && !state->dts_cred.dcr_destructive) {
12911 rval = EACCES;
12912 goto out;
12913 }
12914
12915 dtrace_state_prereserve(state);
12916
12917 /*
12918 * Now we want to do is try to allocate our speculations.
12919 * We do not automatically resize the number of speculations; if
12920 * this fails, we will fail the operation.
12921 */
12922 nspec = opt[DTRACEOPT_NSPEC];
12923 ASSERT(nspec != DTRACEOPT_UNSET);
12924
12925 if (nspec > INT_MAX) {
12926 rval = ENOMEM;
12927 goto out;
12928 }
12929
12930 spec = kmem_zalloc(nspec * sizeof (dtrace_speculation_t),
12931 KM_NOSLEEP | KM_NORMALPRI);
12932
12933 if (spec == NULL) {
12934 rval = ENOMEM;
12935 goto out;
12936 }
12937
12938 state->dts_speculations = spec;
12939 state->dts_nspeculations = (int)nspec;
12940
12941 for (i = 0; i < nspec; i++) {
12942 if ((buf = kmem_zalloc(bufsize,
12943 KM_NOSLEEP | KM_NORMALPRI)) == NULL) {
12944 rval = ENOMEM;
12945 goto err;
12946 }
12947
12948 spec[i].dtsp_buffer = buf;
12949 }
12950
12951 if (opt[DTRACEOPT_GRABANON] != DTRACEOPT_UNSET) {
12952 if (dtrace_anon.dta_state == NULL) {
12953 rval = ENOENT;
12954 goto out;
12955 }
12956
12957 if (state->dts_necbs != 0) {
12958 rval = EALREADY;
12959 goto out;
12960 }
12961
12962 state->dts_anon = dtrace_anon_grab();
12963 ASSERT(state->dts_anon != NULL);
12964 state = state->dts_anon;
12965
12966 /*
12967 * We want "grabanon" to be set in the grabbed state, so we'll
12968 * copy that option value from the grabbing state into the
12969 * grabbed state.
12970 */
12971 state->dts_options[DTRACEOPT_GRABANON] =
12972 opt[DTRACEOPT_GRABANON];
12973
12974 *cpu = dtrace_anon.dta_beganon;
12975
12976 /*
12977 * If the anonymous state is active (as it almost certainly
12978 * is if the anonymous enabling ultimately matched anything),
12979 * we don't allow any further option processing -- but we
12980 * don't return failure.
12981 */
12982 if (state->dts_activity != DTRACE_ACTIVITY_INACTIVE)
12983 goto out;
12984 }
12985
12986 if (opt[DTRACEOPT_AGGSIZE] != DTRACEOPT_UNSET &&
12987 opt[DTRACEOPT_AGGSIZE] != 0) {
12988 if (state->dts_aggregations == NULL) {
12989 /*
12990 * We're not going to create an aggregation buffer
12991 * because we don't have any ECBs that contain
12992 * aggregations -- set this option to 0.
12993 */
12994 opt[DTRACEOPT_AGGSIZE] = 0;
12995 } else {
12996 /*
12997 * If we have an aggregation buffer, we must also have
12998 * a buffer to use as scratch.
12999 */
13000 if (opt[DTRACEOPT_BUFSIZE] == DTRACEOPT_UNSET ||
13001 opt[DTRACEOPT_BUFSIZE] < state->dts_needed) {
13002 opt[DTRACEOPT_BUFSIZE] = state->dts_needed;
13003 }
13004 }
13005 }
13006
13007 if (opt[DTRACEOPT_SPECSIZE] != DTRACEOPT_UNSET &&
13008 opt[DTRACEOPT_SPECSIZE] != 0) {
13009 if (!state->dts_speculates) {
13010 /*
13011 * We're not going to create speculation buffers
13012 * because we don't have any ECBs that actually
13013 * speculate -- set the speculation size to 0.
13014 */
13015 opt[DTRACEOPT_SPECSIZE] = 0;
13016 }
13017 }
13018
13019 /*
13020 * The bare minimum size for any buffer that we're actually going to
13021 * do anything to is sizeof (uint64_t).
13022 */
13023 sz = sizeof (uint64_t);
13024
13025 if ((state->dts_needed != 0 && opt[DTRACEOPT_BUFSIZE] < sz) ||
13026 (state->dts_speculates && opt[DTRACEOPT_SPECSIZE] < sz) ||
13027 (state->dts_aggregations != NULL && opt[DTRACEOPT_AGGSIZE] < sz)) {
13028 /*
13029 * A buffer size has been explicitly set to 0 (or to a size
13030 * that will be adjusted to 0) and we need the space -- we
13031 * need to return failure. We return ENOSPC to differentiate
13032 * it from failing to allocate a buffer due to failure to meet
13033 * the reserve (for which we return E2BIG).
13034 */
13035 rval = ENOSPC;
13036 goto out;
13037 }
13038
13039 if ((rval = dtrace_state_buffers(state)) != 0)
13040 goto err;
13041
13042 if ((sz = opt[DTRACEOPT_DYNVARSIZE]) == DTRACEOPT_UNSET)
13043 sz = dtrace_dstate_defsize;
13044
13045 do {
13046 rval = dtrace_dstate_init(&state->dts_vstate.dtvs_dynvars, sz);
13047
13048 if (rval == 0)
13049 break;
13050
13051 if (opt[DTRACEOPT_BUFRESIZE] == DTRACEOPT_BUFRESIZE_MANUAL)
13052 goto err;
13053 } while (sz >>= 1);
13054
13055 opt[DTRACEOPT_DYNVARSIZE] = sz;
13056
13057 if (rval != 0)
13058 goto err;
13059
13060 if (opt[DTRACEOPT_STATUSRATE] > dtrace_statusrate_max)
13061 opt[DTRACEOPT_STATUSRATE] = dtrace_statusrate_max;
13062
13063 if (opt[DTRACEOPT_CLEANRATE] == 0)
13064 opt[DTRACEOPT_CLEANRATE] = dtrace_cleanrate_max;
13065
13066 if (opt[DTRACEOPT_CLEANRATE] < dtrace_cleanrate_min)
13067 opt[DTRACEOPT_CLEANRATE] = dtrace_cleanrate_min;
13068
13069 if (opt[DTRACEOPT_CLEANRATE] > dtrace_cleanrate_max)
13070 opt[DTRACEOPT_CLEANRATE] = dtrace_cleanrate_max;
13071
13072 hdlr.cyh_func = (cyc_func_t)dtrace_state_clean;
13073 hdlr.cyh_arg = state;
13074 hdlr.cyh_level = CY_LOW_LEVEL;
13075
13076 when.cyt_when = 0;
13077 when.cyt_interval = opt[DTRACEOPT_CLEANRATE];
13078
13079 state->dts_cleaner = cyclic_add(&hdlr, &when);
13080
13081 hdlr.cyh_func = (cyc_func_t)dtrace_state_deadman;
13082 hdlr.cyh_arg = state;
13083 hdlr.cyh_level = CY_LOW_LEVEL;
13084
13085 when.cyt_when = 0;
13086 when.cyt_interval = dtrace_deadman_interval;
13087
13088 state->dts_alive = state->dts_laststatus = dtrace_gethrtime();
13089 state->dts_deadman = cyclic_add(&hdlr, &when);
13090
13091 state->dts_activity = DTRACE_ACTIVITY_WARMUP;
13092
13093 /*
13094 * Now it's time to actually fire the BEGIN probe. We need to disable
13095 * interrupts here both to record the CPU on which we fired the BEGIN
13096 * probe (the data from this CPU will be processed first at user
13097 * level) and to manually activate the buffer for this CPU.
13098 */
13099 cookie = dtrace_interrupt_disable();
13100 *cpu = CPU->cpu_id;
13101 ASSERT(state->dts_buffer[*cpu].dtb_flags & DTRACEBUF_INACTIVE);
13102 state->dts_buffer[*cpu].dtb_flags &= ~DTRACEBUF_INACTIVE;
13103
13104 dtrace_probe(dtrace_probeid_begin,
13105 (uint64_t)(uintptr_t)state, 0, 0, 0, 0);
13106 dtrace_interrupt_enable(cookie);
13107 /*
13108 * We may have had an exit action from a BEGIN probe; only change our
13109 * state to ACTIVE if we're still in WARMUP.
13110 */
13111 ASSERT(state->dts_activity == DTRACE_ACTIVITY_WARMUP ||
13112 state->dts_activity == DTRACE_ACTIVITY_DRAINING);
13113
13114 if (state->dts_activity == DTRACE_ACTIVITY_WARMUP)
13115 state->dts_activity = DTRACE_ACTIVITY_ACTIVE;
13116
13117 /*
13118 * Regardless of whether or not now we're in ACTIVE or DRAINING, we
13119 * want each CPU to transition its principal buffer out of the
13120 * INACTIVE state. Doing this assures that no CPU will suddenly begin
13121 * processing an ECB halfway down a probe's ECB chain; all CPUs will
13122 * atomically transition from processing none of a state's ECBs to
13123 * processing all of them.
13124 */
13125 dtrace_xcall(DTRACE_CPUALL,
13126 (dtrace_xcall_t)dtrace_buffer_activate, state);
13127 goto out;
13128
13129 err:
13130 dtrace_buffer_free(state->dts_buffer);
13131 dtrace_buffer_free(state->dts_aggbuffer);
13132
13133 if ((nspec = state->dts_nspeculations) == 0) {
13134 ASSERT(state->dts_speculations == NULL);
13135 goto out;
13136 }
13137
13138 spec = state->dts_speculations;
13139 ASSERT(spec != NULL);
13140
13141 for (i = 0; i < state->dts_nspeculations; i++) {
13142 if ((buf = spec[i].dtsp_buffer) == NULL)
13143 break;
13144
13145 dtrace_buffer_free(buf);
13146 kmem_free(buf, bufsize);
13147 }
13148
13149 kmem_free(spec, nspec * sizeof (dtrace_speculation_t));
13150 state->dts_nspeculations = 0;
13151 state->dts_speculations = NULL;
13152
13153 out:
13154 mutex_exit(&dtrace_lock);
13155 mutex_exit(&cpu_lock);
13156
13157 return (rval);
13158 }
13159
13160 static int
13161 dtrace_state_stop(dtrace_state_t *state, processorid_t *cpu)
13162 {
13163 dtrace_icookie_t cookie;
13164
13165 ASSERT(MUTEX_HELD(&dtrace_lock));
13166
13167 if (state->dts_activity != DTRACE_ACTIVITY_ACTIVE &&
13168 state->dts_activity != DTRACE_ACTIVITY_DRAINING)
13169 return (EINVAL);
13170
13171 /*
13172 * We'll set the activity to DTRACE_ACTIVITY_DRAINING, and issue a sync
13173 * to be sure that every CPU has seen it. See below for the details
13174 * on why this is done.
13175 */
13176 state->dts_activity = DTRACE_ACTIVITY_DRAINING;
13177 dtrace_sync();
13178
13179 /*
13180 * By this point, it is impossible for any CPU to be still processing
13181 * with DTRACE_ACTIVITY_ACTIVE. We can thus set our activity to
13182 * DTRACE_ACTIVITY_COOLDOWN and know that we're not racing with any
13183 * other CPU in dtrace_buffer_reserve(). This allows dtrace_probe()
13184 * and callees to know that the activity is DTRACE_ACTIVITY_COOLDOWN
13185 * iff we're in the END probe.
13186 */
13187 state->dts_activity = DTRACE_ACTIVITY_COOLDOWN;
13188 dtrace_sync();
13189 ASSERT(state->dts_activity == DTRACE_ACTIVITY_COOLDOWN);
13190
13191 /*
13192 * Finally, we can release the reserve and call the END probe. We
13193 * disable interrupts across calling the END probe to allow us to
13194 * return the CPU on which we actually called the END probe. This
13195 * allows user-land to be sure that this CPU's principal buffer is
13196 * processed last.
13197 */
13198 state->dts_reserve = 0;
13199
13200 cookie = dtrace_interrupt_disable();
13201 *cpu = CPU->cpu_id;
13202 dtrace_probe(dtrace_probeid_end,
13203 (uint64_t)(uintptr_t)state, 0, 0, 0, 0);
13204 dtrace_interrupt_enable(cookie);
13205
13206 state->dts_activity = DTRACE_ACTIVITY_STOPPED;
13207 dtrace_sync();
13208
13209 return (0);
13210 }
13211
13212 static int
13213 dtrace_state_option(dtrace_state_t *state, dtrace_optid_t option,
13214 dtrace_optval_t val)
13215 {
13216 ASSERT(MUTEX_HELD(&dtrace_lock));
13217
13218 if (state->dts_activity != DTRACE_ACTIVITY_INACTIVE)
13219 return (EBUSY);
13220
13221 if (option >= DTRACEOPT_MAX)
13222 return (EINVAL);
13223
13224 if (option != DTRACEOPT_CPU && val < 0)
13225 return (EINVAL);
13226
13227 switch (option) {
13228 case DTRACEOPT_DESTRUCTIVE:
13229 if (dtrace_destructive_disallow)
13230 return (EACCES);
13231
13232 state->dts_cred.dcr_destructive = 1;
13233 break;
13234
13235 case DTRACEOPT_BUFSIZE:
13236 case DTRACEOPT_DYNVARSIZE:
13237 case DTRACEOPT_AGGSIZE:
13238 case DTRACEOPT_SPECSIZE:
13239 case DTRACEOPT_STRSIZE:
13240 if (val < 0)
13241 return (EINVAL);
13242
13243 if (val >= LONG_MAX) {
13244 /*
13245 * If this is an otherwise negative value, set it to
13246 * the highest multiple of 128m less than LONG_MAX.
13247 * Technically, we're adjusting the size without
13248 * regard to the buffer resizing policy, but in fact,
13249 * this has no effect -- if we set the buffer size to
13250 * ~LONG_MAX and the buffer policy is ultimately set to
13251 * be "manual", the buffer allocation is guaranteed to
13252 * fail, if only because the allocation requires two
13253 * buffers. (We set the the size to the highest
13254 * multiple of 128m because it ensures that the size
13255 * will remain a multiple of a megabyte when
13256 * repeatedly halved -- all the way down to 15m.)
13257 */
13258 val = LONG_MAX - (1 << 27) + 1;
13259 }
13260 }
13261
13262 state->dts_options[option] = val;
13263
13264 return (0);
13265 }
13266
13267 static void
13268 dtrace_state_destroy(dtrace_state_t *state)
13269 {
13270 dtrace_ecb_t *ecb;
13271 dtrace_vstate_t *vstate = &state->dts_vstate;
13272 minor_t minor = getminor(state->dts_dev);
13273 int i, bufsize = NCPU * sizeof (dtrace_buffer_t);
13274 dtrace_speculation_t *spec = state->dts_speculations;
13275 int nspec = state->dts_nspeculations;
13276 uint32_t match;
13277
13278 ASSERT(MUTEX_HELD(&dtrace_lock));
13279 ASSERT(MUTEX_HELD(&cpu_lock));
13280
13281 /*
13282 * First, retract any retained enablings for this state.
13283 */
13284 dtrace_enabling_retract(state);
13285 ASSERT(state->dts_nretained == 0);
13286
13287 if (state->dts_activity == DTRACE_ACTIVITY_ACTIVE ||
13288 state->dts_activity == DTRACE_ACTIVITY_DRAINING) {
13289 /*
13290 * We have managed to come into dtrace_state_destroy() on a
13291 * hot enabling -- almost certainly because of a disorderly
13292 * shutdown of a consumer. (That is, a consumer that is
13293 * exiting without having called dtrace_stop().) In this case,
13294 * we're going to set our activity to be KILLED, and then
13295 * issue a sync to be sure that everyone is out of probe
13296 * context before we start blowing away ECBs.
13297 */
13298 state->dts_activity = DTRACE_ACTIVITY_KILLED;
13299 dtrace_sync();
13300 }
13301
13302 /*
13303 * Release the credential hold we took in dtrace_state_create().
13304 */
13305 if (state->dts_cred.dcr_cred != NULL)
13306 crfree(state->dts_cred.dcr_cred);
13307
13308 /*
13309 * Now we can safely disable and destroy any enabled probes. Because
13310 * any DTRACE_PRIV_KERNEL probes may actually be slowing our progress
13311 * (especially if they're all enabled), we take two passes through the
13312 * ECBs: in the first, we disable just DTRACE_PRIV_KERNEL probes, and
13313 * in the second we disable whatever is left over.
13314 */
13315 for (match = DTRACE_PRIV_KERNEL; ; match = 0) {
13316 for (i = 0; i < state->dts_necbs; i++) {
13317 if ((ecb = state->dts_ecbs[i]) == NULL)
13318 continue;
13319
13320 if (match && ecb->dte_probe != NULL) {
13321 dtrace_probe_t *probe = ecb->dte_probe;
13322 dtrace_provider_t *prov = probe->dtpr_provider;
13323
13324 if (!(prov->dtpv_priv.dtpp_flags & match))
13325 continue;
13326 }
13327
13328 dtrace_ecb_disable(ecb);
13329 dtrace_ecb_destroy(ecb);
13330 }
13331
13332 if (!match)
13333 break;
13334 }
13335
13336 /*
13337 * Before we free the buffers, perform one more sync to assure that
13338 * every CPU is out of probe context.
13339 */
13340 dtrace_sync();
13341
13342 dtrace_buffer_free(state->dts_buffer);
13343 dtrace_buffer_free(state->dts_aggbuffer);
13344
13345 for (i = 0; i < nspec; i++)
13346 dtrace_buffer_free(spec[i].dtsp_buffer);
13347
13348 if (state->dts_cleaner != CYCLIC_NONE)
13349 cyclic_remove(state->dts_cleaner);
13350
13351 if (state->dts_deadman != CYCLIC_NONE)
13352 cyclic_remove(state->dts_deadman);
13353
13354 dtrace_dstate_fini(&vstate->dtvs_dynvars);
13355 dtrace_vstate_fini(vstate);
13356 kmem_free(state->dts_ecbs, state->dts_necbs * sizeof (dtrace_ecb_t *));
13357
13358 if (state->dts_aggregations != NULL) {
13359 #ifdef DEBUG
13360 for (i = 0; i < state->dts_naggregations; i++)
13361 ASSERT(state->dts_aggregations[i] == NULL);
13362 #endif
13363 ASSERT(state->dts_naggregations > 0);
13364 kmem_free(state->dts_aggregations,
13365 state->dts_naggregations * sizeof (dtrace_aggregation_t *));
13366 }
13367
13368 kmem_free(state->dts_buffer, bufsize);
13369 kmem_free(state->dts_aggbuffer, bufsize);
13370
13371 for (i = 0; i < nspec; i++)
13372 kmem_free(spec[i].dtsp_buffer, bufsize);
13373
13374 kmem_free(spec, nspec * sizeof (dtrace_speculation_t));
13375
13376 dtrace_format_destroy(state);
13377
13378 vmem_destroy(state->dts_aggid_arena);
13379 ddi_soft_state_free(dtrace_softstate, minor);
13380 vmem_free(dtrace_minor, (void *)(uintptr_t)minor, 1);
13381 }
13382
13383 /*
13384 * DTrace Anonymous Enabling Functions
13385 */
13386 static dtrace_state_t *
13387 dtrace_anon_grab(void)
13388 {
13389 dtrace_state_t *state;
13390
13391 ASSERT(MUTEX_HELD(&dtrace_lock));
13392
13393 if ((state = dtrace_anon.dta_state) == NULL) {
13394 ASSERT(dtrace_anon.dta_enabling == NULL);
13395 return (NULL);
13396 }
13397
13398 ASSERT(dtrace_anon.dta_enabling != NULL);
13399 ASSERT(dtrace_retained != NULL);
13400
13401 dtrace_enabling_destroy(dtrace_anon.dta_enabling);
13402 dtrace_anon.dta_enabling = NULL;
13403 dtrace_anon.dta_state = NULL;
13404
13405 return (state);
13406 }
13407
13408 static void
13409 dtrace_anon_property(void)
13410 {
13411 int i, rv;
13412 dtrace_state_t *state;
13413 dof_hdr_t *dof;
13414 char c[32]; /* enough for "dof-data-" + digits */
13415
13416 ASSERT(MUTEX_HELD(&dtrace_lock));
13417 ASSERT(MUTEX_HELD(&cpu_lock));
13418
13419 for (i = 0; ; i++) {
13420 (void) snprintf(c, sizeof (c), "dof-data-%d", i);
13421
13422 dtrace_err_verbose = 1;
13423
13424 if ((dof = dtrace_dof_property(c)) == NULL) {
13425 dtrace_err_verbose = 0;
13426 break;
13427 }
13428
13429 /*
13430 * We want to create anonymous state, so we need to transition
13431 * the kernel debugger to indicate that DTrace is active. If
13432 * this fails (e.g. because the debugger has modified text in
13433 * some way), we won't continue with the processing.
13434 */
13435 if (kdi_dtrace_set(KDI_DTSET_DTRACE_ACTIVATE) != 0) {
13436 cmn_err(CE_NOTE, "kernel debugger active; anonymous "
13437 "enabling ignored.");
13438 dtrace_dof_destroy(dof);
13439 break;
13440 }
13441
13442 /*
13443 * If we haven't allocated an anonymous state, we'll do so now.
13444 */
13445 if ((state = dtrace_anon.dta_state) == NULL) {
13446 state = dtrace_state_create(NULL, NULL);
13447 dtrace_anon.dta_state = state;
13448
13449 if (state == NULL) {
13450 /*
13451 * This basically shouldn't happen: the only
13452 * failure mode from dtrace_state_create() is a
13453 * failure of ddi_soft_state_zalloc() that
13454 * itself should never happen. Still, the
13455 * interface allows for a failure mode, and
13456 * we want to fail as gracefully as possible:
13457 * we'll emit an error message and cease
13458 * processing anonymous state in this case.
13459 */
13460 cmn_err(CE_WARN, "failed to create "
13461 "anonymous state");
13462 dtrace_dof_destroy(dof);
13463 break;
13464 }
13465 }
13466
13467 rv = dtrace_dof_slurp(dof, &state->dts_vstate, CRED(),
13468 &dtrace_anon.dta_enabling, 0, B_TRUE);
13469
13470 if (rv == 0)
13471 rv = dtrace_dof_options(dof, state);
13472
13473 dtrace_err_verbose = 0;
13474 dtrace_dof_destroy(dof);
13475
13476 if (rv != 0) {
13477 /*
13478 * This is malformed DOF; chuck any anonymous state
13479 * that we created.
13480 */
13481 ASSERT(dtrace_anon.dta_enabling == NULL);
13482 dtrace_state_destroy(state);
13483 dtrace_anon.dta_state = NULL;
13484 break;
13485 }
13486
13487 ASSERT(dtrace_anon.dta_enabling != NULL);
13488 }
13489
13490 if (dtrace_anon.dta_enabling != NULL) {
13491 int rval;
13492
13493 /*
13494 * dtrace_enabling_retain() can only fail because we are
13495 * trying to retain more enablings than are allowed -- but
13496 * we only have one anonymous enabling, and we are guaranteed
13497 * to be allowed at least one retained enabling; we assert
13498 * that dtrace_enabling_retain() returns success.
13499 */
13500 rval = dtrace_enabling_retain(dtrace_anon.dta_enabling);
13501 ASSERT(rval == 0);
13502
13503 dtrace_enabling_dump(dtrace_anon.dta_enabling);
13504 }
13505 }
13506
13507 /*
13508 * DTrace Helper Functions
13509 */
13510 static void
13511 dtrace_helper_trace(dtrace_helper_action_t *helper,
13512 dtrace_mstate_t *mstate, dtrace_vstate_t *vstate, int where)
13513 {
13514 uint32_t size, next, nnext, i;
13515 dtrace_helptrace_t *ent;
13516 uint16_t flags = cpu_core[CPU->cpu_id].cpuc_dtrace_flags;
13517
13518 if (!dtrace_helptrace_enabled)
13519 return;
13520
13521 ASSERT(vstate->dtvs_nlocals <= dtrace_helptrace_nlocals);
13522
13523 /*
13524 * What would a tracing framework be without its own tracing
13525 * framework? (Well, a hell of a lot simpler, for starters...)
13526 */
13527 size = sizeof (dtrace_helptrace_t) + dtrace_helptrace_nlocals *
13528 sizeof (uint64_t) - sizeof (uint64_t);
13529
13530 /*
13531 * Iterate until we can allocate a slot in the trace buffer.
13532 */
13533 do {
13534 next = dtrace_helptrace_next;
13535
13536 if (next + size < dtrace_helptrace_bufsize) {
13537 nnext = next + size;
13538 } else {
13539 nnext = size;
13540 }
13541 } while (dtrace_cas32(&dtrace_helptrace_next, next, nnext) != next);
13542
13543 /*
13544 * We have our slot; fill it in.
13545 */
13546 if (nnext == size)
13547 next = 0;
13548
13549 ent = (dtrace_helptrace_t *)&dtrace_helptrace_buffer[next];
13550 ent->dtht_helper = helper;
13551 ent->dtht_where = where;
13552 ent->dtht_nlocals = vstate->dtvs_nlocals;
13553
13554 ent->dtht_fltoffs = (mstate->dtms_present & DTRACE_MSTATE_FLTOFFS) ?
13555 mstate->dtms_fltoffs : -1;
13556 ent->dtht_fault = DTRACE_FLAGS2FLT(flags);
13557 ent->dtht_illval = cpu_core[CPU->cpu_id].cpuc_dtrace_illval;
13558
13559 for (i = 0; i < vstate->dtvs_nlocals; i++) {
13560 dtrace_statvar_t *svar;
13561
13562 if ((svar = vstate->dtvs_locals[i]) == NULL)
13563 continue;
13564
13565 ASSERT(svar->dtsv_size >= NCPU * sizeof (uint64_t));
13566 ent->dtht_locals[i] =
13567 ((uint64_t *)(uintptr_t)svar->dtsv_data)[CPU->cpu_id];
13568 }
13569 }
13570
13571 static uint64_t
13572 dtrace_helper(int which, dtrace_mstate_t *mstate,
13573 dtrace_state_t *state, uint64_t arg0, uint64_t arg1)
13574 {
13575 uint16_t *flags = &cpu_core[CPU->cpu_id].cpuc_dtrace_flags;
13576 uint64_t sarg0 = mstate->dtms_arg[0];
13577 uint64_t sarg1 = mstate->dtms_arg[1];
13578 uint64_t rval;
13579 dtrace_helpers_t *helpers = curproc->p_dtrace_helpers;
13580 dtrace_helper_action_t *helper;
13581 dtrace_vstate_t *vstate;
13582 dtrace_difo_t *pred;
13583 int i, trace = dtrace_helptrace_enabled;
13584
13585 ASSERT(which >= 0 && which < DTRACE_NHELPER_ACTIONS);
13586
13587 if (helpers == NULL)
13588 return (0);
13589
13590 if ((helper = helpers->dthps_actions[which]) == NULL)
13591 return (0);
13592
13593 vstate = &helpers->dthps_vstate;
13594 mstate->dtms_arg[0] = arg0;
13595 mstate->dtms_arg[1] = arg1;
13596
13597 /*
13598 * Now iterate over each helper. If its predicate evaluates to 'true',
13599 * we'll call the corresponding actions. Note that the below calls
13600 * to dtrace_dif_emulate() may set faults in machine state. This is
13601 * okay: our caller (the outer dtrace_dif_emulate()) will simply plow
13602 * the stored DIF offset with its own (which is the desired behavior).
13603 * Also, note the calls to dtrace_dif_emulate() may allocate scratch
13604 * from machine state; this is okay, too.
13605 */
13606 for (; helper != NULL; helper = helper->dtha_next) {
13607 if ((pred = helper->dtha_predicate) != NULL) {
13608 if (trace)
13609 dtrace_helper_trace(helper, mstate, vstate, 0);
13610
13611 if (!dtrace_dif_emulate(pred, mstate, vstate, state))
13612 goto next;
13613
13614 if (*flags & CPU_DTRACE_FAULT)
13615 goto err;
13616 }
13617
13618 for (i = 0; i < helper->dtha_nactions; i++) {
13619 if (trace)
13620 dtrace_helper_trace(helper,
13621 mstate, vstate, i + 1);
13622
13623 rval = dtrace_dif_emulate(helper->dtha_actions[i],
13624 mstate, vstate, state);
13625
13626 if (*flags & CPU_DTRACE_FAULT)
13627 goto err;
13628 }
13629
13630 next:
13631 if (trace)
13632 dtrace_helper_trace(helper, mstate, vstate,
13633 DTRACE_HELPTRACE_NEXT);
13634 }
13635
13636 if (trace)
13637 dtrace_helper_trace(helper, mstate, vstate,
13638 DTRACE_HELPTRACE_DONE);
13639
13640 /*
13641 * Restore the arg0 that we saved upon entry.
13642 */
13643 mstate->dtms_arg[0] = sarg0;
13644 mstate->dtms_arg[1] = sarg1;
13645
13646 return (rval);
13647
13648 err:
13649 if (trace)
13650 dtrace_helper_trace(helper, mstate, vstate,
13651 DTRACE_HELPTRACE_ERR);
13652
13653 /*
13654 * Restore the arg0 that we saved upon entry.
13655 */
13656 mstate->dtms_arg[0] = sarg0;
13657 mstate->dtms_arg[1] = sarg1;
13658
13659 return (NULL);
13660 }
13661
13662 static void
13663 dtrace_helper_action_destroy(dtrace_helper_action_t *helper,
13664 dtrace_vstate_t *vstate)
13665 {
13666 int i;
13667
13668 if (helper->dtha_predicate != NULL)
13669 dtrace_difo_release(helper->dtha_predicate, vstate);
13670
13671 for (i = 0; i < helper->dtha_nactions; i++) {
13672 ASSERT(helper->dtha_actions[i] != NULL);
13673 dtrace_difo_release(helper->dtha_actions[i], vstate);
13674 }
13675
13676 kmem_free(helper->dtha_actions,
13677 helper->dtha_nactions * sizeof (dtrace_difo_t *));
13678 kmem_free(helper, sizeof (dtrace_helper_action_t));
13679 }
13680
13681 static int
13682 dtrace_helper_destroygen(int gen)
13683 {
13684 proc_t *p = curproc;
13685 dtrace_helpers_t *help = p->p_dtrace_helpers;
13686 dtrace_vstate_t *vstate;
13687 int i;
13688
13689 ASSERT(MUTEX_HELD(&dtrace_lock));
13690
13691 if (help == NULL || gen > help->dthps_generation)
13692 return (EINVAL);
13693
13694 vstate = &help->dthps_vstate;
13695
13696 for (i = 0; i < DTRACE_NHELPER_ACTIONS; i++) {
13697 dtrace_helper_action_t *last = NULL, *h, *next;
13698
13699 for (h = help->dthps_actions[i]; h != NULL; h = next) {
13700 next = h->dtha_next;
13701
13702 if (h->dtha_generation == gen) {
13703 if (last != NULL) {
13704 last->dtha_next = next;
13705 } else {
13706 help->dthps_actions[i] = next;
13707 }
13708
13709 dtrace_helper_action_destroy(h, vstate);
13710 } else {
13711 last = h;
13712 }
13713 }
13714 }
13715
13716 /*
13717 * Interate until we've cleared out all helper providers with the
13718 * given generation number.
13719 */
13720 for (;;) {
13721 dtrace_helper_provider_t *prov;
13722
13723 /*
13724 * Look for a helper provider with the right generation. We
13725 * have to start back at the beginning of the list each time
13726 * because we drop dtrace_lock. It's unlikely that we'll make
13727 * more than two passes.
13728 */
13729 for (i = 0; i < help->dthps_nprovs; i++) {
13730 prov = help->dthps_provs[i];
13731
13732 if (prov->dthp_generation == gen)
13733 break;
13734 }
13735
13736 /*
13737 * If there were no matches, we're done.
13738 */
13739 if (i == help->dthps_nprovs)
13740 break;
13741
13742 /*
13743 * Move the last helper provider into this slot.
13744 */
13745 help->dthps_nprovs--;
13746 help->dthps_provs[i] = help->dthps_provs[help->dthps_nprovs];
13747 help->dthps_provs[help->dthps_nprovs] = NULL;
13748
13749 mutex_exit(&dtrace_lock);
13750
13751 /*
13752 * If we have a meta provider, remove this helper provider.
13753 */
13754 mutex_enter(&dtrace_meta_lock);
13755 if (dtrace_meta_pid != NULL) {
13756 ASSERT(dtrace_deferred_pid == NULL);
13757 dtrace_helper_provider_remove(&prov->dthp_prov,
13758 p->p_pid);
13759 }
13760 mutex_exit(&dtrace_meta_lock);
13761
13762 dtrace_helper_provider_destroy(prov);
13763
13764 mutex_enter(&dtrace_lock);
13765 }
13766
13767 return (0);
13768 }
13769
13770 static int
13771 dtrace_helper_validate(dtrace_helper_action_t *helper)
13772 {
13773 int err = 0, i;
13774 dtrace_difo_t *dp;
13775
13776 if ((dp = helper->dtha_predicate) != NULL)
13777 err += dtrace_difo_validate_helper(dp);
13778
13779 for (i = 0; i < helper->dtha_nactions; i++)
13780 err += dtrace_difo_validate_helper(helper->dtha_actions[i]);
13781
13782 return (err == 0);
13783 }
13784
13785 static int
13786 dtrace_helper_action_add(int which, dtrace_ecbdesc_t *ep)
13787 {
13788 dtrace_helpers_t *help;
13789 dtrace_helper_action_t *helper, *last;
13790 dtrace_actdesc_t *act;
13791 dtrace_vstate_t *vstate;
13792 dtrace_predicate_t *pred;
13793 int count = 0, nactions = 0, i;
13794
13795 if (which < 0 || which >= DTRACE_NHELPER_ACTIONS)
13796 return (EINVAL);
13797
13798 help = curproc->p_dtrace_helpers;
13799 last = help->dthps_actions[which];
13800 vstate = &help->dthps_vstate;
13801
13802 for (count = 0; last != NULL; last = last->dtha_next) {
13803 count++;
13804 if (last->dtha_next == NULL)
13805 break;
13806 }
13807
13808 /*
13809 * If we already have dtrace_helper_actions_max helper actions for this
13810 * helper action type, we'll refuse to add a new one.
13811 */
13812 if (count >= dtrace_helper_actions_max)
13813 return (ENOSPC);
13814
13815 helper = kmem_zalloc(sizeof (dtrace_helper_action_t), KM_SLEEP);
13816 helper->dtha_generation = help->dthps_generation;
13817
13818 if ((pred = ep->dted_pred.dtpdd_predicate) != NULL) {
13819 ASSERT(pred->dtp_difo != NULL);
13820 dtrace_difo_hold(pred->dtp_difo);
13821 helper->dtha_predicate = pred->dtp_difo;
13822 }
13823
13824 for (act = ep->dted_action; act != NULL; act = act->dtad_next) {
13825 if (act->dtad_kind != DTRACEACT_DIFEXPR)
13826 goto err;
13827
13828 if (act->dtad_difo == NULL)
13829 goto err;
13830
13831 nactions++;
13832 }
13833
13834 helper->dtha_actions = kmem_zalloc(sizeof (dtrace_difo_t *) *
13835 (helper->dtha_nactions = nactions), KM_SLEEP);
13836
13837 for (act = ep->dted_action, i = 0; act != NULL; act = act->dtad_next) {
13838 dtrace_difo_hold(act->dtad_difo);
13839 helper->dtha_actions[i++] = act->dtad_difo;
13840 }
13841
13842 if (!dtrace_helper_validate(helper))
13843 goto err;
13844
13845 if (last == NULL) {
13846 help->dthps_actions[which] = helper;
13847 } else {
13848 last->dtha_next = helper;
13849 }
13850
13851 if (vstate->dtvs_nlocals > dtrace_helptrace_nlocals) {
13852 dtrace_helptrace_nlocals = vstate->dtvs_nlocals;
13853 dtrace_helptrace_next = 0;
13854 }
13855
13856 return (0);
13857 err:
13858 dtrace_helper_action_destroy(helper, vstate);
13859 return (EINVAL);
13860 }
13861
13862 static void
13863 dtrace_helper_provider_register(proc_t *p, dtrace_helpers_t *help,
13864 dof_helper_t *dofhp)
13865 {
13866 ASSERT(MUTEX_NOT_HELD(&dtrace_lock));
13867
13868 mutex_enter(&dtrace_meta_lock);
13869 mutex_enter(&dtrace_lock);
13870
13871 if (!dtrace_attached() || dtrace_meta_pid == NULL) {
13872 /*
13873 * If the dtrace module is loaded but not attached, or if
13874 * there aren't isn't a meta provider registered to deal with
13875 * these provider descriptions, we need to postpone creating
13876 * the actual providers until later.
13877 */
13878
13879 if (help->dthps_next == NULL && help->dthps_prev == NULL &&
13880 dtrace_deferred_pid != help) {
13881 help->dthps_deferred = 1;
13882 help->dthps_pid = p->p_pid;
13883 help->dthps_next = dtrace_deferred_pid;
13884 help->dthps_prev = NULL;
13885 if (dtrace_deferred_pid != NULL)
13886 dtrace_deferred_pid->dthps_prev = help;
13887 dtrace_deferred_pid = help;
13888 }
13889
13890 mutex_exit(&dtrace_lock);
13891
13892 } else if (dofhp != NULL) {
13893 /*
13894 * If the dtrace module is loaded and we have a particular
13895 * helper provider description, pass that off to the
13896 * meta provider.
13897 */
13898
13899 mutex_exit(&dtrace_lock);
13900
13901 dtrace_helper_provide(dofhp, p->p_pid);
13902
13903 } else {
13904 /*
13905 * Otherwise, just pass all the helper provider descriptions
13906 * off to the meta provider.
13907 */
13908
13909 int i;
13910 mutex_exit(&dtrace_lock);
13911
13912 for (i = 0; i < help->dthps_nprovs; i++) {
13913 dtrace_helper_provide(&help->dthps_provs[i]->dthp_prov,
13914 p->p_pid);
13915 }
13916 }
13917
13918 mutex_exit(&dtrace_meta_lock);
13919 }
13920
13921 static int
13922 dtrace_helper_provider_add(dof_helper_t *dofhp, int gen)
13923 {
13924 dtrace_helpers_t *help;
13925 dtrace_helper_provider_t *hprov, **tmp_provs;
13926 uint_t tmp_maxprovs, i;
13927
13928 ASSERT(MUTEX_HELD(&dtrace_lock));
13929
13930 help = curproc->p_dtrace_helpers;
13931 ASSERT(help != NULL);
13932
13933 /*
13934 * If we already have dtrace_helper_providers_max helper providers,
13935 * we're refuse to add a new one.
13936 */
13937 if (help->dthps_nprovs >= dtrace_helper_providers_max)
13938 return (ENOSPC);
13939
13940 /*
13941 * Check to make sure this isn't a duplicate.
13942 */
13943 for (i = 0; i < help->dthps_nprovs; i++) {
13944 if (dofhp->dofhp_dof ==
13945 help->dthps_provs[i]->dthp_prov.dofhp_dof)
13946 return (EALREADY);
13947 }
13948
13949 hprov = kmem_zalloc(sizeof (dtrace_helper_provider_t), KM_SLEEP);
13950 hprov->dthp_prov = *dofhp;
13951 hprov->dthp_ref = 1;
13952 hprov->dthp_generation = gen;
13953
13954 /*
13955 * Allocate a bigger table for helper providers if it's already full.
13956 */
13957 if (help->dthps_maxprovs == help->dthps_nprovs) {
13958 tmp_maxprovs = help->dthps_maxprovs;
13959 tmp_provs = help->dthps_provs;
13960
13961 if (help->dthps_maxprovs == 0)
13962 help->dthps_maxprovs = 2;
13963 else
13964 help->dthps_maxprovs *= 2;
13965 if (help->dthps_maxprovs > dtrace_helper_providers_max)
13966 help->dthps_maxprovs = dtrace_helper_providers_max;
13967
13968 ASSERT(tmp_maxprovs < help->dthps_maxprovs);
13969
13970 help->dthps_provs = kmem_zalloc(help->dthps_maxprovs *
13971 sizeof (dtrace_helper_provider_t *), KM_SLEEP);
13972
13973 if (tmp_provs != NULL) {
13974 bcopy(tmp_provs, help->dthps_provs, tmp_maxprovs *
13975 sizeof (dtrace_helper_provider_t *));
13976 kmem_free(tmp_provs, tmp_maxprovs *
13977 sizeof (dtrace_helper_provider_t *));
13978 }
13979 }
13980
13981 help->dthps_provs[help->dthps_nprovs] = hprov;
13982 help->dthps_nprovs++;
13983
13984 return (0);
13985 }
13986
13987 static void
13988 dtrace_helper_provider_destroy(dtrace_helper_provider_t *hprov)
13989 {
13990 mutex_enter(&dtrace_lock);
13991
13992 if (--hprov->dthp_ref == 0) {
13993 dof_hdr_t *dof;
13994 mutex_exit(&dtrace_lock);
13995 dof = (dof_hdr_t *)(uintptr_t)hprov->dthp_prov.dofhp_dof;
13996 dtrace_dof_destroy(dof);
13997 kmem_free(hprov, sizeof (dtrace_helper_provider_t));
13998 } else {
13999 mutex_exit(&dtrace_lock);
14000 }
14001 }
14002
14003 static int
14004 dtrace_helper_provider_validate(dof_hdr_t *dof, dof_sec_t *sec)
14005 {
14006 uintptr_t daddr = (uintptr_t)dof;
14007 dof_sec_t *str_sec, *prb_sec, *arg_sec, *off_sec, *enoff_sec;
14008 dof_provider_t *provider;
14009 dof_probe_t *probe;
14010 uint8_t *arg;
14011 char *strtab, *typestr;
14012 dof_stridx_t typeidx;
14013 size_t typesz;
14014 uint_t nprobes, j, k;
14015
14016 ASSERT(sec->dofs_type == DOF_SECT_PROVIDER);
14017
14018 if (sec->dofs_offset & (sizeof (uint_t) - 1)) {
14019 dtrace_dof_error(dof, "misaligned section offset");
14020 return (-1);
14021 }
14022
14023 /*
14024 * The section needs to be large enough to contain the DOF provider
14025 * structure appropriate for the given version.
14026 */
14027 if (sec->dofs_size <
14028 ((dof->dofh_ident[DOF_ID_VERSION] == DOF_VERSION_1) ?
14029 offsetof(dof_provider_t, dofpv_prenoffs) :
14030 sizeof (dof_provider_t))) {
14031 dtrace_dof_error(dof, "provider section too small");
14032 return (-1);
14033 }
14034
14035 provider = (dof_provider_t *)(uintptr_t)(daddr + sec->dofs_offset);
14036 str_sec = dtrace_dof_sect(dof, DOF_SECT_STRTAB, provider->dofpv_strtab);
14037 prb_sec = dtrace_dof_sect(dof, DOF_SECT_PROBES, provider->dofpv_probes);
14038 arg_sec = dtrace_dof_sect(dof, DOF_SECT_PRARGS, provider->dofpv_prargs);
14039 off_sec = dtrace_dof_sect(dof, DOF_SECT_PROFFS, provider->dofpv_proffs);
14040
14041 if (str_sec == NULL || prb_sec == NULL ||
14042 arg_sec == NULL || off_sec == NULL)
14043 return (-1);
14044
14045 enoff_sec = NULL;
14046
14047 if (dof->dofh_ident[DOF_ID_VERSION] != DOF_VERSION_1 &&
14048 provider->dofpv_prenoffs != DOF_SECT_NONE &&
14049 (enoff_sec = dtrace_dof_sect(dof, DOF_SECT_PRENOFFS,
14050 provider->dofpv_prenoffs)) == NULL)
14051 return (-1);
14052
14053 strtab = (char *)(uintptr_t)(daddr + str_sec->dofs_offset);
14054
14055 if (provider->dofpv_name >= str_sec->dofs_size ||
14056 strlen(strtab + provider->dofpv_name) >= DTRACE_PROVNAMELEN) {
14057 dtrace_dof_error(dof, "invalid provider name");
14058 return (-1);
14059 }
14060
14061 if (prb_sec->dofs_entsize == 0 ||
14062 prb_sec->dofs_entsize > prb_sec->dofs_size) {
14063 dtrace_dof_error(dof, "invalid entry size");
14064 return (-1);
14065 }
14066
14067 if (prb_sec->dofs_entsize & (sizeof (uintptr_t) - 1)) {
14068 dtrace_dof_error(dof, "misaligned entry size");
14069 return (-1);
14070 }
14071
14072 if (off_sec->dofs_entsize != sizeof (uint32_t)) {
14073 dtrace_dof_error(dof, "invalid entry size");
14074 return (-1);
14075 }
14076
14077 if (off_sec->dofs_offset & (sizeof (uint32_t) - 1)) {
14078 dtrace_dof_error(dof, "misaligned section offset");
14079 return (-1);
14080 }
14081
14082 if (arg_sec->dofs_entsize != sizeof (uint8_t)) {
14083 dtrace_dof_error(dof, "invalid entry size");
14084 return (-1);
14085 }
14086
14087 arg = (uint8_t *)(uintptr_t)(daddr + arg_sec->dofs_offset);
14088
14089 nprobes = prb_sec->dofs_size / prb_sec->dofs_entsize;
14090
14091 /*
14092 * Take a pass through the probes to check for errors.
14093 */
14094 for (j = 0; j < nprobes; j++) {
14095 probe = (dof_probe_t *)(uintptr_t)(daddr +
14096 prb_sec->dofs_offset + j * prb_sec->dofs_entsize);
14097
14098 if (probe->dofpr_func >= str_sec->dofs_size) {
14099 dtrace_dof_error(dof, "invalid function name");
14100 return (-1);
14101 }
14102
14103 if (strlen(strtab + probe->dofpr_func) >= DTRACE_FUNCNAMELEN) {
14104 dtrace_dof_error(dof, "function name too long");
14105 return (-1);
14106 }
14107
14108 if (probe->dofpr_name >= str_sec->dofs_size ||
14109 strlen(strtab + probe->dofpr_name) >= DTRACE_NAMELEN) {
14110 dtrace_dof_error(dof, "invalid probe name");
14111 return (-1);
14112 }
14113
14114 /*
14115 * The offset count must not wrap the index, and the offsets
14116 * must also not overflow the section's data.
14117 */
14118 if (probe->dofpr_offidx + probe->dofpr_noffs <
14119 probe->dofpr_offidx ||
14120 (probe->dofpr_offidx + probe->dofpr_noffs) *
14121 off_sec->dofs_entsize > off_sec->dofs_size) {
14122 dtrace_dof_error(dof, "invalid probe offset");
14123 return (-1);
14124 }
14125
14126 if (dof->dofh_ident[DOF_ID_VERSION] != DOF_VERSION_1) {
14127 /*
14128 * If there's no is-enabled offset section, make sure
14129 * there aren't any is-enabled offsets. Otherwise
14130 * perform the same checks as for probe offsets
14131 * (immediately above).
14132 */
14133 if (enoff_sec == NULL) {
14134 if (probe->dofpr_enoffidx != 0 ||
14135 probe->dofpr_nenoffs != 0) {
14136 dtrace_dof_error(dof, "is-enabled "
14137 "offsets with null section");
14138 return (-1);
14139 }
14140 } else if (probe->dofpr_enoffidx +
14141 probe->dofpr_nenoffs < probe->dofpr_enoffidx ||
14142 (probe->dofpr_enoffidx + probe->dofpr_nenoffs) *
14143 enoff_sec->dofs_entsize > enoff_sec->dofs_size) {
14144 dtrace_dof_error(dof, "invalid is-enabled "
14145 "offset");
14146 return (-1);
14147 }
14148
14149 if (probe->dofpr_noffs + probe->dofpr_nenoffs == 0) {
14150 dtrace_dof_error(dof, "zero probe and "
14151 "is-enabled offsets");
14152 return (-1);
14153 }
14154 } else if (probe->dofpr_noffs == 0) {
14155 dtrace_dof_error(dof, "zero probe offsets");
14156 return (-1);
14157 }
14158
14159 if (probe->dofpr_argidx + probe->dofpr_xargc <
14160 probe->dofpr_argidx ||
14161 (probe->dofpr_argidx + probe->dofpr_xargc) *
14162 arg_sec->dofs_entsize > arg_sec->dofs_size) {
14163 dtrace_dof_error(dof, "invalid args");
14164 return (-1);
14165 }
14166
14167 typeidx = probe->dofpr_nargv;
14168 typestr = strtab + probe->dofpr_nargv;
14169 for (k = 0; k < probe->dofpr_nargc; k++) {
14170 if (typeidx >= str_sec->dofs_size) {
14171 dtrace_dof_error(dof, "bad "
14172 "native argument type");
14173 return (-1);
14174 }
14175
14176 typesz = strlen(typestr) + 1;
14177 if (typesz > DTRACE_ARGTYPELEN) {
14178 dtrace_dof_error(dof, "native "
14179 "argument type too long");
14180 return (-1);
14181 }
14182 typeidx += typesz;
14183 typestr += typesz;
14184 }
14185
14186 typeidx = probe->dofpr_xargv;
14187 typestr = strtab + probe->dofpr_xargv;
14188 for (k = 0; k < probe->dofpr_xargc; k++) {
14189 if (arg[probe->dofpr_argidx + k] > probe->dofpr_nargc) {
14190 dtrace_dof_error(dof, "bad "
14191 "native argument index");
14192 return (-1);
14193 }
14194
14195 if (typeidx >= str_sec->dofs_size) {
14196 dtrace_dof_error(dof, "bad "
14197 "translated argument type");
14198 return (-1);
14199 }
14200
14201 typesz = strlen(typestr) + 1;
14202 if (typesz > DTRACE_ARGTYPELEN) {
14203 dtrace_dof_error(dof, "translated argument "
14204 "type too long");
14205 return (-1);
14206 }
14207
14208 typeidx += typesz;
14209 typestr += typesz;
14210 }
14211 }
14212
14213 return (0);
14214 }
14215
14216 static int
14217 dtrace_helper_slurp(dof_hdr_t *dof, dof_helper_t *dhp)
14218 {
14219 dtrace_helpers_t *help;
14220 dtrace_vstate_t *vstate;
14221 dtrace_enabling_t *enab = NULL;
14222 int i, gen, rv, nhelpers = 0, nprovs = 0, destroy = 1;
14223 uintptr_t daddr = (uintptr_t)dof;
14224
14225 ASSERT(MUTEX_HELD(&dtrace_lock));
14226
14227 if ((help = curproc->p_dtrace_helpers) == NULL)
14228 help = dtrace_helpers_create(curproc);
14229
14230 vstate = &help->dthps_vstate;
14231
14232 if ((rv = dtrace_dof_slurp(dof, vstate, NULL, &enab,
14233 dhp != NULL ? dhp->dofhp_addr : 0, B_FALSE)) != 0) {
14234 dtrace_dof_destroy(dof);
14235 return (rv);
14236 }
14237
14238 /*
14239 * Look for helper providers and validate their descriptions.
14240 */
14241 if (dhp != NULL) {
14242 for (i = 0; i < dof->dofh_secnum; i++) {
14243 dof_sec_t *sec = (dof_sec_t *)(uintptr_t)(daddr +
14244 dof->dofh_secoff + i * dof->dofh_secsize);
14245
14246 if (sec->dofs_type != DOF_SECT_PROVIDER)
14247 continue;
14248
14249 if (dtrace_helper_provider_validate(dof, sec) != 0) {
14250 dtrace_enabling_destroy(enab);
14251 dtrace_dof_destroy(dof);
14252 return (-1);
14253 }
14254
14255 nprovs++;
14256 }
14257 }
14258
14259 /*
14260 * Now we need to walk through the ECB descriptions in the enabling.
14261 */
14262 for (i = 0; i < enab->dten_ndesc; i++) {
14263 dtrace_ecbdesc_t *ep = enab->dten_desc[i];
14264 dtrace_probedesc_t *desc = &ep->dted_probe;
14265
14266 if (strcmp(desc->dtpd_provider, "dtrace") != 0)
14267 continue;
14268
14269 if (strcmp(desc->dtpd_mod, "helper") != 0)
14270 continue;
14271
14272 if (strcmp(desc->dtpd_func, "ustack") != 0)
14273 continue;
14274
14275 if ((rv = dtrace_helper_action_add(DTRACE_HELPER_ACTION_USTACK,
14276 ep)) != 0) {
14277 /*
14278 * Adding this helper action failed -- we are now going
14279 * to rip out the entire generation and return failure.
14280 */
14281 (void) dtrace_helper_destroygen(help->dthps_generation);
14282 dtrace_enabling_destroy(enab);
14283 dtrace_dof_destroy(dof);
14284 return (-1);
14285 }
14286
14287 nhelpers++;
14288 }
14289
14290 if (nhelpers < enab->dten_ndesc)
14291 dtrace_dof_error(dof, "unmatched helpers");
14292
14293 gen = help->dthps_generation++;
14294 dtrace_enabling_destroy(enab);
14295
14296 if (dhp != NULL && nprovs > 0) {
14297 dhp->dofhp_dof = (uint64_t)(uintptr_t)dof;
14298 if (dtrace_helper_provider_add(dhp, gen) == 0) {
14299 mutex_exit(&dtrace_lock);
14300 dtrace_helper_provider_register(curproc, help, dhp);
14301 mutex_enter(&dtrace_lock);
14302
14303 destroy = 0;
14304 }
14305 }
14306
14307 if (destroy)
14308 dtrace_dof_destroy(dof);
14309
14310 return (gen);
14311 }
14312
14313 static dtrace_helpers_t *
14314 dtrace_helpers_create(proc_t *p)
14315 {
14316 dtrace_helpers_t *help;
14317
14318 ASSERT(MUTEX_HELD(&dtrace_lock));
14319 ASSERT(p->p_dtrace_helpers == NULL);
14320
14321 help = kmem_zalloc(sizeof (dtrace_helpers_t), KM_SLEEP);
14322 help->dthps_actions = kmem_zalloc(sizeof (dtrace_helper_action_t *) *
14323 DTRACE_NHELPER_ACTIONS, KM_SLEEP);
14324
14325 p->p_dtrace_helpers = help;
14326 dtrace_helpers++;
14327
14328 return (help);
14329 }
14330
14331 static void
14332 dtrace_helpers_destroy(void)
14333 {
14334 dtrace_helpers_t *help;
14335 dtrace_vstate_t *vstate;
14336 proc_t *p = curproc;
14337 int i;
14338
14339 mutex_enter(&dtrace_lock);
14340
14341 ASSERT(p->p_dtrace_helpers != NULL);
14342 ASSERT(dtrace_helpers > 0);
14343
14344 help = p->p_dtrace_helpers;
14345 vstate = &help->dthps_vstate;
14346
14347 /*
14348 * We're now going to lose the help from this process.
14349 */
14350 p->p_dtrace_helpers = NULL;
14351 dtrace_sync();
14352
14353 /*
14354 * Destory the helper actions.
14355 */
14356 for (i = 0; i < DTRACE_NHELPER_ACTIONS; i++) {
14357 dtrace_helper_action_t *h, *next;
14358
14359 for (h = help->dthps_actions[i]; h != NULL; h = next) {
14360 next = h->dtha_next;
14361 dtrace_helper_action_destroy(h, vstate);
14362 h = next;
14363 }
14364 }
14365
14366 mutex_exit(&dtrace_lock);
14367
14368 /*
14369 * Destroy the helper providers.
14370 */
14371 if (help->dthps_maxprovs > 0) {
14372 mutex_enter(&dtrace_meta_lock);
14373 if (dtrace_meta_pid != NULL) {
14374 ASSERT(dtrace_deferred_pid == NULL);
14375
14376 for (i = 0; i < help->dthps_nprovs; i++) {
14377 dtrace_helper_provider_remove(
14378 &help->dthps_provs[i]->dthp_prov, p->p_pid);
14379 }
14380 } else {
14381 mutex_enter(&dtrace_lock);
14382 ASSERT(help->dthps_deferred == 0 ||
14383 help->dthps_next != NULL ||
14384 help->dthps_prev != NULL ||
14385 help == dtrace_deferred_pid);
14386
14387 /*
14388 * Remove the helper from the deferred list.
14389 */
14390 if (help->dthps_next != NULL)
14391 help->dthps_next->dthps_prev = help->dthps_prev;
14392 if (help->dthps_prev != NULL)
14393 help->dthps_prev->dthps_next = help->dthps_next;
14394 if (dtrace_deferred_pid == help) {
14395 dtrace_deferred_pid = help->dthps_next;
14396 ASSERT(help->dthps_prev == NULL);
14397 }
14398
14399 mutex_exit(&dtrace_lock);
14400 }
14401
14402 mutex_exit(&dtrace_meta_lock);
14403
14404 for (i = 0; i < help->dthps_nprovs; i++) {
14405 dtrace_helper_provider_destroy(help->dthps_provs[i]);
14406 }
14407
14408 kmem_free(help->dthps_provs, help->dthps_maxprovs *
14409 sizeof (dtrace_helper_provider_t *));
14410 }
14411
14412 mutex_enter(&dtrace_lock);
14413
14414 dtrace_vstate_fini(&help->dthps_vstate);
14415 kmem_free(help->dthps_actions,
14416 sizeof (dtrace_helper_action_t *) * DTRACE_NHELPER_ACTIONS);
14417 kmem_free(help, sizeof (dtrace_helpers_t));
14418
14419 --dtrace_helpers;
14420 mutex_exit(&dtrace_lock);
14421 }
14422
14423 static void
14424 dtrace_helpers_duplicate(proc_t *from, proc_t *to)
14425 {
14426 dtrace_helpers_t *help, *newhelp;
14427 dtrace_helper_action_t *helper, *new, *last;
14428 dtrace_difo_t *dp;
14429 dtrace_vstate_t *vstate;
14430 int i, j, sz, hasprovs = 0;
14431
14432 mutex_enter(&dtrace_lock);
14433 ASSERT(from->p_dtrace_helpers != NULL);
14434 ASSERT(dtrace_helpers > 0);
14435
14436 help = from->p_dtrace_helpers;
14437 newhelp = dtrace_helpers_create(to);
14438 ASSERT(to->p_dtrace_helpers != NULL);
14439
14440 newhelp->dthps_generation = help->dthps_generation;
14441 vstate = &newhelp->dthps_vstate;
14442
14443 /*
14444 * Duplicate the helper actions.
14445 */
14446 for (i = 0; i < DTRACE_NHELPER_ACTIONS; i++) {
14447 if ((helper = help->dthps_actions[i]) == NULL)
14448 continue;
14449
14450 for (last = NULL; helper != NULL; helper = helper->dtha_next) {
14451 new = kmem_zalloc(sizeof (dtrace_helper_action_t),
14452 KM_SLEEP);
14453 new->dtha_generation = helper->dtha_generation;
14454
14455 if ((dp = helper->dtha_predicate) != NULL) {
14456 dp = dtrace_difo_duplicate(dp, vstate);
14457 new->dtha_predicate = dp;
14458 }
14459
14460 new->dtha_nactions = helper->dtha_nactions;
14461 sz = sizeof (dtrace_difo_t *) * new->dtha_nactions;
14462 new->dtha_actions = kmem_alloc(sz, KM_SLEEP);
14463
14464 for (j = 0; j < new->dtha_nactions; j++) {
14465 dtrace_difo_t *dp = helper->dtha_actions[j];
14466
14467 ASSERT(dp != NULL);
14468 dp = dtrace_difo_duplicate(dp, vstate);
14469 new->dtha_actions[j] = dp;
14470 }
14471
14472 if (last != NULL) {
14473 last->dtha_next = new;
14474 } else {
14475 newhelp->dthps_actions[i] = new;
14476 }
14477
14478 last = new;
14479 }
14480 }
14481
14482 /*
14483 * Duplicate the helper providers and register them with the
14484 * DTrace framework.
14485 */
14486 if (help->dthps_nprovs > 0) {
14487 newhelp->dthps_nprovs = help->dthps_nprovs;
14488 newhelp->dthps_maxprovs = help->dthps_nprovs;
14489 newhelp->dthps_provs = kmem_alloc(newhelp->dthps_nprovs *
14490 sizeof (dtrace_helper_provider_t *), KM_SLEEP);
14491 for (i = 0; i < newhelp->dthps_nprovs; i++) {
14492 newhelp->dthps_provs[i] = help->dthps_provs[i];
14493 newhelp->dthps_provs[i]->dthp_ref++;
14494 }
14495
14496 hasprovs = 1;
14497 }
14498
14499 mutex_exit(&dtrace_lock);
14500
14501 if (hasprovs)
14502 dtrace_helper_provider_register(to, newhelp, NULL);
14503 }
14504
14505 /*
14506 * DTrace Hook Functions
14507 */
14508 static void
14509 dtrace_module_loaded(struct modctl *ctl)
14510 {
14511 dtrace_provider_t *prv;
14512
14513 mutex_enter(&dtrace_provider_lock);
14514 mutex_enter(&mod_lock);
14515
14516 ASSERT(ctl->mod_busy);
14517
14518 /*
14519 * We're going to call each providers per-module provide operation
14520 * specifying only this module.
14521 */
14522 for (prv = dtrace_provider; prv != NULL; prv = prv->dtpv_next)
14523 prv->dtpv_pops.dtps_provide_module(prv->dtpv_arg, ctl);
14524
14525 mutex_exit(&mod_lock);
14526 mutex_exit(&dtrace_provider_lock);
14527
14528 /*
14529 * If we have any retained enablings, we need to match against them.
14530 * Enabling probes requires that cpu_lock be held, and we cannot hold
14531 * cpu_lock here -- it is legal for cpu_lock to be held when loading a
14532 * module. (In particular, this happens when loading scheduling
14533 * classes.) So if we have any retained enablings, we need to dispatch
14534 * our task queue to do the match for us.
14535 */
14536 mutex_enter(&dtrace_lock);
14537
14538 if (dtrace_retained == NULL) {
14539 mutex_exit(&dtrace_lock);
14540 return;
14541 }
14542
14543 (void) taskq_dispatch(dtrace_taskq,
14544 (task_func_t *)dtrace_enabling_matchall, NULL, TQ_SLEEP);
14545
14546 mutex_exit(&dtrace_lock);
14547
14548 /*
14549 * And now, for a little heuristic sleaze: in general, we want to
14550 * match modules as soon as they load. However, we cannot guarantee
14551 * this, because it would lead us to the lock ordering violation
14552 * outlined above. The common case, of course, is that cpu_lock is
14553 * _not_ held -- so we delay here for a clock tick, hoping that that's
14554 * long enough for the task queue to do its work. If it's not, it's
14555 * not a serious problem -- it just means that the module that we
14556 * just loaded may not be immediately instrumentable.
14557 */
14558 delay(1);
14559 }
14560
14561 static void
14562 dtrace_module_unloaded(struct modctl *ctl)
14563 {
14564 dtrace_probe_t template, *probe, *first, *next;
14565 dtrace_provider_t *prov;
14566
14567 template.dtpr_mod = ctl->mod_modname;
14568
14569 mutex_enter(&dtrace_provider_lock);
14570 mutex_enter(&mod_lock);
14571 mutex_enter(&dtrace_lock);
14572
14573 if (dtrace_bymod == NULL) {
14574 /*
14575 * The DTrace module is loaded (obviously) but not attached;
14576 * we don't have any work to do.
14577 */
14578 mutex_exit(&dtrace_provider_lock);
14579 mutex_exit(&mod_lock);
14580 mutex_exit(&dtrace_lock);
14581 return;
14582 }
14583
14584 for (probe = first = dtrace_hash_lookup(dtrace_bymod, &template);
14585 probe != NULL; probe = probe->dtpr_nextmod) {
14586 if (probe->dtpr_ecb != NULL) {
14587 mutex_exit(&dtrace_provider_lock);
14588 mutex_exit(&mod_lock);
14589 mutex_exit(&dtrace_lock);
14590
14591 /*
14592 * This shouldn't _actually_ be possible -- we're
14593 * unloading a module that has an enabled probe in it.
14594 * (It's normally up to the provider to make sure that
14595 * this can't happen.) However, because dtps_enable()
14596 * doesn't have a failure mode, there can be an
14597 * enable/unload race. Upshot: we don't want to
14598 * assert, but we're not going to disable the
14599 * probe, either.
14600 */
14601 if (dtrace_err_verbose) {
14602 cmn_err(CE_WARN, "unloaded module '%s' had "
14603 "enabled probes", ctl->mod_modname);
14604 }
14605
14606 return;
14607 }
14608 }
14609
14610 probe = first;
14611
14612 for (first = NULL; probe != NULL; probe = next) {
14613 ASSERT(dtrace_probes[probe->dtpr_id - 1] == probe);
14614
14615 dtrace_probes[probe->dtpr_id - 1] = NULL;
14616
14617 next = probe->dtpr_nextmod;
14618 dtrace_hash_remove(dtrace_bymod, probe);
14619 dtrace_hash_remove(dtrace_byfunc, probe);
14620 dtrace_hash_remove(dtrace_byname, probe);
14621
14622 if (first == NULL) {
14623 first = probe;
14624 probe->dtpr_nextmod = NULL;
14625 } else {
14626 probe->dtpr_nextmod = first;
14627 first = probe;
14628 }
14629 }
14630
14631 /*
14632 * We've removed all of the module's probes from the hash chains and
14633 * from the probe array. Now issue a dtrace_sync() to be sure that
14634 * everyone has cleared out from any probe array processing.
14635 */
14636 dtrace_sync();
14637
14638 for (probe = first; probe != NULL; probe = first) {
14639 first = probe->dtpr_nextmod;
14640 prov = probe->dtpr_provider;
14641 prov->dtpv_pops.dtps_destroy(prov->dtpv_arg, probe->dtpr_id,
14642 probe->dtpr_arg);
14643 kmem_free(probe->dtpr_mod, strlen(probe->dtpr_mod) + 1);
14644 kmem_free(probe->dtpr_func, strlen(probe->dtpr_func) + 1);
14645 kmem_free(probe->dtpr_name, strlen(probe->dtpr_name) + 1);
14646 vmem_free(dtrace_arena, (void *)(uintptr_t)probe->dtpr_id, 1);
14647 kmem_free(probe, sizeof (dtrace_probe_t));
14648 }
14649
14650 mutex_exit(&dtrace_lock);
14651 mutex_exit(&mod_lock);
14652 mutex_exit(&dtrace_provider_lock);
14653 }
14654
14655 void
14656 dtrace_suspend(void)
14657 {
14658 dtrace_probe_foreach(offsetof(dtrace_pops_t, dtps_suspend));
14659 }
14660
14661 void
14662 dtrace_resume(void)
14663 {
14664 dtrace_probe_foreach(offsetof(dtrace_pops_t, dtps_resume));
14665 }
14666
14667 static int
14668 dtrace_cpu_setup(cpu_setup_t what, processorid_t cpu)
14669 {
14670 ASSERT(MUTEX_HELD(&cpu_lock));
14671 mutex_enter(&dtrace_lock);
14672
14673 switch (what) {
14674 case CPU_CONFIG: {
14675 dtrace_state_t *state;
14676 dtrace_optval_t *opt, rs, c;
14677
14678 /*
14679 * For now, we only allocate a new buffer for anonymous state.
14680 */
14681 if ((state = dtrace_anon.dta_state) == NULL)
14682 break;
14683
14684 if (state->dts_activity != DTRACE_ACTIVITY_ACTIVE)
14685 break;
14686
14687 opt = state->dts_options;
14688 c = opt[DTRACEOPT_CPU];
14689
14690 if (c != DTRACE_CPUALL && c != DTRACEOPT_UNSET && c != cpu)
14691 break;
14692
14693 /*
14694 * Regardless of what the actual policy is, we're going to
14695 * temporarily set our resize policy to be manual. We're
14696 * also going to temporarily set our CPU option to denote
14697 * the newly configured CPU.
14698 */
14699 rs = opt[DTRACEOPT_BUFRESIZE];
14700 opt[DTRACEOPT_BUFRESIZE] = DTRACEOPT_BUFRESIZE_MANUAL;
14701 opt[DTRACEOPT_CPU] = (dtrace_optval_t)cpu;
14702
14703 (void) dtrace_state_buffers(state);
14704
14705 opt[DTRACEOPT_BUFRESIZE] = rs;
14706 opt[DTRACEOPT_CPU] = c;
14707
14708 break;
14709 }
14710
14711 case CPU_UNCONFIG:
14712 /*
14713 * We don't free the buffer in the CPU_UNCONFIG case. (The
14714 * buffer will be freed when the consumer exits.)
14715 */
14716 break;
14717
14718 default:
14719 break;
14720 }
14721
14722 mutex_exit(&dtrace_lock);
14723 return (0);
14724 }
14725
14726 static void
14727 dtrace_cpu_setup_initial(processorid_t cpu)
14728 {
14729 (void) dtrace_cpu_setup(CPU_CONFIG, cpu);
14730 }
14731
14732 static void
14733 dtrace_toxrange_add(uintptr_t base, uintptr_t limit)
14734 {
14735 if (dtrace_toxranges >= dtrace_toxranges_max) {
14736 int osize, nsize;
14737 dtrace_toxrange_t *range;
14738
14739 osize = dtrace_toxranges_max * sizeof (dtrace_toxrange_t);
14740
14741 if (osize == 0) {
14742 ASSERT(dtrace_toxrange == NULL);
14743 ASSERT(dtrace_toxranges_max == 0);
14744 dtrace_toxranges_max = 1;
14745 } else {
14746 dtrace_toxranges_max <<= 1;
14747 }
14748
14749 nsize = dtrace_toxranges_max * sizeof (dtrace_toxrange_t);
14750 range = kmem_zalloc(nsize, KM_SLEEP);
14751
14752 if (dtrace_toxrange != NULL) {
14753 ASSERT(osize != 0);
14754 bcopy(dtrace_toxrange, range, osize);
14755 kmem_free(dtrace_toxrange, osize);
14756 }
14757
14758 dtrace_toxrange = range;
14759 }
14760
14761 ASSERT(dtrace_toxrange[dtrace_toxranges].dtt_base == NULL);
14762 ASSERT(dtrace_toxrange[dtrace_toxranges].dtt_limit == NULL);
14763
14764 dtrace_toxrange[dtrace_toxranges].dtt_base = base;
14765 dtrace_toxrange[dtrace_toxranges].dtt_limit = limit;
14766 dtrace_toxranges++;
14767 }
14768
14769 /*
14770 * DTrace Driver Cookbook Functions
14771 */
14772 /*ARGSUSED*/
14773 static int
14774 dtrace_attach(dev_info_t *devi, ddi_attach_cmd_t cmd)
14775 {
14776 dtrace_provider_id_t id;
14777 dtrace_state_t *state = NULL;
14778 dtrace_enabling_t *enab;
14779
14780 mutex_enter(&cpu_lock);
14781 mutex_enter(&dtrace_provider_lock);
14782 mutex_enter(&dtrace_lock);
14783
14784 if (ddi_soft_state_init(&dtrace_softstate,
14785 sizeof (dtrace_state_t), 0) != 0) {
14786 cmn_err(CE_NOTE, "/dev/dtrace failed to initialize soft state");
14787 mutex_exit(&cpu_lock);
14788 mutex_exit(&dtrace_provider_lock);
14789 mutex_exit(&dtrace_lock);
14790 return (DDI_FAILURE);
14791 }
14792
14793 if (ddi_create_minor_node(devi, DTRACEMNR_DTRACE, S_IFCHR,
14794 DTRACEMNRN_DTRACE, DDI_PSEUDO, NULL) == DDI_FAILURE ||
14795 ddi_create_minor_node(devi, DTRACEMNR_HELPER, S_IFCHR,
14796 DTRACEMNRN_HELPER, DDI_PSEUDO, NULL) == DDI_FAILURE) {
14797 cmn_err(CE_NOTE, "/dev/dtrace couldn't create minor nodes");
14798 ddi_remove_minor_node(devi, NULL);
14799 ddi_soft_state_fini(&dtrace_softstate);
14800 mutex_exit(&cpu_lock);
14801 mutex_exit(&dtrace_provider_lock);
14802 mutex_exit(&dtrace_lock);
14803 return (DDI_FAILURE);
14804 }
14805
14806 ddi_report_dev(devi);
14807 dtrace_devi = devi;
14808
14809 dtrace_modload = dtrace_module_loaded;
14810 dtrace_modunload = dtrace_module_unloaded;
14811 dtrace_cpu_init = dtrace_cpu_setup_initial;
14812 dtrace_helpers_cleanup = dtrace_helpers_destroy;
14813 dtrace_helpers_fork = dtrace_helpers_duplicate;
14814 dtrace_cpustart_init = dtrace_suspend;
14815 dtrace_cpustart_fini = dtrace_resume;
14816 dtrace_debugger_init = dtrace_suspend;
14817 dtrace_debugger_fini = dtrace_resume;
14818
14819 register_cpu_setup_func((cpu_setup_func_t *)dtrace_cpu_setup, NULL);
14820
14821 ASSERT(MUTEX_HELD(&cpu_lock));
14822
14823 dtrace_arena = vmem_create("dtrace", (void *)1, UINT32_MAX, 1,
14824 NULL, NULL, NULL, 0, VM_SLEEP | VMC_IDENTIFIER);
14825 dtrace_minor = vmem_create("dtrace_minor", (void *)DTRACEMNRN_CLONE,
14826 UINT32_MAX - DTRACEMNRN_CLONE, 1, NULL, NULL, NULL, 0,
14827 VM_SLEEP | VMC_IDENTIFIER);
14828 dtrace_taskq = taskq_create("dtrace_taskq", 1, maxclsyspri,
14829 1, INT_MAX, 0);
14830
14831 dtrace_state_cache = kmem_cache_create("dtrace_state_cache",
14832 sizeof (dtrace_dstate_percpu_t) * NCPU, DTRACE_STATE_ALIGN,
14833 NULL, NULL, NULL, NULL, NULL, 0);
14834
14835 ASSERT(MUTEX_HELD(&cpu_lock));
14836 dtrace_bymod = dtrace_hash_create(offsetof(dtrace_probe_t, dtpr_mod),
14837 offsetof(dtrace_probe_t, dtpr_nextmod),
14838 offsetof(dtrace_probe_t, dtpr_prevmod));
14839
14840 dtrace_byfunc = dtrace_hash_create(offsetof(dtrace_probe_t, dtpr_func),
14841 offsetof(dtrace_probe_t, dtpr_nextfunc),
14842 offsetof(dtrace_probe_t, dtpr_prevfunc));
14843
14844 dtrace_byname = dtrace_hash_create(offsetof(dtrace_probe_t, dtpr_name),
14845 offsetof(dtrace_probe_t, dtpr_nextname),
14846 offsetof(dtrace_probe_t, dtpr_prevname));
14847
14848 if (dtrace_retain_max < 1) {
14849 cmn_err(CE_WARN, "illegal value (%lu) for dtrace_retain_max; "
14850 "setting to 1", dtrace_retain_max);
14851 dtrace_retain_max = 1;
14852 }
14853
14854 /*
14855 * Now discover our toxic ranges.
14856 */
14857 dtrace_toxic_ranges(dtrace_toxrange_add);
14858
14859 /*
14860 * Before we register ourselves as a provider to our own framework,
14861 * we would like to assert that dtrace_provider is NULL -- but that's
14862 * not true if we were loaded as a dependency of a DTrace provider.
14863 * Once we've registered, we can assert that dtrace_provider is our
14864 * pseudo provider.
14865 */
14866 (void) dtrace_register("dtrace", &dtrace_provider_attr,
14867 DTRACE_PRIV_NONE, 0, &dtrace_provider_ops, NULL, &id);
14868
14869 ASSERT(dtrace_provider != NULL);
14870 ASSERT((dtrace_provider_id_t)dtrace_provider == id);
14871
14872 dtrace_probeid_begin = dtrace_probe_create((dtrace_provider_id_t)
14873 dtrace_provider, NULL, NULL, "BEGIN", 0, NULL);
14874 dtrace_probeid_end = dtrace_probe_create((dtrace_provider_id_t)
14875 dtrace_provider, NULL, NULL, "END", 0, NULL);
14876 dtrace_probeid_error = dtrace_probe_create((dtrace_provider_id_t)
14877 dtrace_provider, NULL, NULL, "ERROR", 1, NULL);
14878
14879 dtrace_anon_property();
14880 mutex_exit(&cpu_lock);
14881
14882 /*
14883 * If DTrace helper tracing is enabled, we need to allocate the
14884 * trace buffer and initialize the values.
14885 */
14886 if (dtrace_helptrace_enabled) {
14887 ASSERT(dtrace_helptrace_buffer == NULL);
14888 dtrace_helptrace_buffer =
14889 kmem_zalloc(dtrace_helptrace_bufsize, KM_SLEEP);
14890 dtrace_helptrace_next = 0;
14891 }
14892
14893 /*
14894 * If there are already providers, we must ask them to provide their
14895 * probes, and then match any anonymous enabling against them. Note
14896 * that there should be no other retained enablings at this time:
14897 * the only retained enablings at this time should be the anonymous
14898 * enabling.
14899 */
14900 if (dtrace_anon.dta_enabling != NULL) {
14901 ASSERT(dtrace_retained == dtrace_anon.dta_enabling);
14902
14903 dtrace_enabling_provide(NULL);
14904 state = dtrace_anon.dta_state;
14905
14906 /*
14907 * We couldn't hold cpu_lock across the above call to
14908 * dtrace_enabling_provide(), but we must hold it to actually
14909 * enable the probes. We have to drop all of our locks, pick
14910 * up cpu_lock, and regain our locks before matching the
14911 * retained anonymous enabling.
14912 */
14913 mutex_exit(&dtrace_lock);
14914 mutex_exit(&dtrace_provider_lock);
14915
14916 mutex_enter(&cpu_lock);
14917 mutex_enter(&dtrace_provider_lock);
14918 mutex_enter(&dtrace_lock);
14919
14920 if ((enab = dtrace_anon.dta_enabling) != NULL)
14921 (void) dtrace_enabling_match(enab, NULL);
14922
14923 mutex_exit(&cpu_lock);
14924 }
14925
14926 mutex_exit(&dtrace_lock);
14927 mutex_exit(&dtrace_provider_lock);
14928
14929 if (state != NULL) {
14930 /*
14931 * If we created any anonymous state, set it going now.
14932 */
14933 (void) dtrace_state_go(state, &dtrace_anon.dta_beganon);
14934 }
14935
14936 return (DDI_SUCCESS);
14937 }
14938
14939 /*ARGSUSED*/
14940 static int
14941 dtrace_open(dev_t *devp, int flag, int otyp, cred_t *cred_p)
14942 {
14943 dtrace_state_t *state;
14944 uint32_t priv;
14945 uid_t uid;
14946 zoneid_t zoneid;
14947
14948 if (getminor(*devp) == DTRACEMNRN_HELPER)
14949 return (0);
14950
14951 /*
14952 * If this wasn't an open with the "helper" minor, then it must be
14953 * the "dtrace" minor.
14954 */
14955 if (getminor(*devp) != DTRACEMNRN_DTRACE)
14956 return (ENXIO);
14957
14958 /*
14959 * If no DTRACE_PRIV_* bits are set in the credential, then the
14960 * caller lacks sufficient permission to do anything with DTrace.
14961 */
14962 dtrace_cred2priv(cred_p, &priv, &uid, &zoneid);
14963 if (priv == DTRACE_PRIV_NONE)
14964 return (EACCES);
14965
14966 /*
14967 * Ask all providers to provide all their probes.
14968 */
14969 mutex_enter(&dtrace_provider_lock);
14970 dtrace_probe_provide(NULL, NULL);
14971 mutex_exit(&dtrace_provider_lock);
14972
14973 mutex_enter(&cpu_lock);
14974 mutex_enter(&dtrace_lock);
14975 dtrace_opens++;
14976 dtrace_membar_producer();
14977
14978 /*
14979 * If the kernel debugger is active (that is, if the kernel debugger
14980 * modified text in some way), we won't allow the open.
14981 */
14982 if (kdi_dtrace_set(KDI_DTSET_DTRACE_ACTIVATE) != 0) {
14983 dtrace_opens--;
14984 mutex_exit(&cpu_lock);
14985 mutex_exit(&dtrace_lock);
14986 return (EBUSY);
14987 }
14988
14989 state = dtrace_state_create(devp, cred_p);
14990 mutex_exit(&cpu_lock);
14991
14992 if (state == NULL) {
14993 if (--dtrace_opens == 0 && dtrace_anon.dta_enabling == NULL)
14994 (void) kdi_dtrace_set(KDI_DTSET_DTRACE_DEACTIVATE);
14995 mutex_exit(&dtrace_lock);
14996 return (EAGAIN);
14997 }
14998
14999 mutex_exit(&dtrace_lock);
15000
15001 return (0);
15002 }
15003
15004 /*ARGSUSED*/
15005 static int
15006 dtrace_close(dev_t dev, int flag, int otyp, cred_t *cred_p)
15007 {
15008 minor_t minor = getminor(dev);
15009 dtrace_state_t *state;
15010
15011 if (minor == DTRACEMNRN_HELPER)
15012 return (0);
15013
15014 state = ddi_get_soft_state(dtrace_softstate, minor);
15015
15016 mutex_enter(&cpu_lock);
15017 mutex_enter(&dtrace_lock);
15018
15019 if (state->dts_anon) {
15020 /*
15021 * There is anonymous state. Destroy that first.
15022 */
15023 ASSERT(dtrace_anon.dta_state == NULL);
15024 dtrace_state_destroy(state->dts_anon);
15025 }
15026
15027 dtrace_state_destroy(state);
15028 ASSERT(dtrace_opens > 0);
15029
15030 /*
15031 * Only relinquish control of the kernel debugger interface when there
15032 * are no consumers and no anonymous enablings.
15033 */
15034 if (--dtrace_opens == 0 && dtrace_anon.dta_enabling == NULL)
15035 (void) kdi_dtrace_set(KDI_DTSET_DTRACE_DEACTIVATE);
15036
15037 mutex_exit(&dtrace_lock);
15038 mutex_exit(&cpu_lock);
15039
15040 return (0);
15041 }
15042
15043 /*ARGSUSED*/
15044 static int
15045 dtrace_ioctl_helper(int cmd, intptr_t arg, int *rv)
15046 {
15047 int rval;
15048 dof_helper_t help, *dhp = NULL;
15049
15050 switch (cmd) {
15051 case DTRACEHIOC_ADDDOF:
15052 if (copyin((void *)arg, &help, sizeof (help)) != 0) {
15053 dtrace_dof_error(NULL, "failed to copyin DOF helper");
15054 return (EFAULT);
15055 }
15056
15057 dhp = &help;
15058 arg = (intptr_t)help.dofhp_dof;
15059 /*FALLTHROUGH*/
15060
15061 case DTRACEHIOC_ADD: {
15062 dof_hdr_t *dof = dtrace_dof_copyin(arg, &rval);
15063
15064 if (dof == NULL)
15065 return (rval);
15066
15067 mutex_enter(&dtrace_lock);
15068
15069 /*
15070 * dtrace_helper_slurp() takes responsibility for the dof --
15071 * it may free it now or it may save it and free it later.
15072 */
15073 if ((rval = dtrace_helper_slurp(dof, dhp)) != -1) {
15074 *rv = rval;
15075 rval = 0;
15076 } else {
15077 rval = EINVAL;
15078 }
15079
15080 mutex_exit(&dtrace_lock);
15081 return (rval);
15082 }
15083
15084 case DTRACEHIOC_REMOVE: {
15085 mutex_enter(&dtrace_lock);
15086 rval = dtrace_helper_destroygen(arg);
15087 mutex_exit(&dtrace_lock);
15088
15089 return (rval);
15090 }
15091
15092 default:
15093 break;
15094 }
15095
15096 return (ENOTTY);
15097 }
15098
15099 /*ARGSUSED*/
15100 static int
15101 dtrace_ioctl(dev_t dev, int cmd, intptr_t arg, int md, cred_t *cr, int *rv)
15102 {
15103 minor_t minor = getminor(dev);
15104 dtrace_state_t *state;
15105 int rval;
15106
15107 if (minor == DTRACEMNRN_HELPER)
15108 return (dtrace_ioctl_helper(cmd, arg, rv));
15109
15110 state = ddi_get_soft_state(dtrace_softstate, minor);
15111
15112 if (state->dts_anon) {
15113 ASSERT(dtrace_anon.dta_state == NULL);
15114 state = state->dts_anon;
15115 }
15116
15117 switch (cmd) {
15118 case DTRACEIOC_PROVIDER: {
15119 dtrace_providerdesc_t pvd;
15120 dtrace_provider_t *pvp;
15121
15122 if (copyin((void *)arg, &pvd, sizeof (pvd)) != 0)
15123 return (EFAULT);
15124
15125 pvd.dtvd_name[DTRACE_PROVNAMELEN - 1] = '\0';
15126 mutex_enter(&dtrace_provider_lock);
15127
15128 for (pvp = dtrace_provider; pvp != NULL; pvp = pvp->dtpv_next) {
15129 if (strcmp(pvp->dtpv_name, pvd.dtvd_name) == 0)
15130 break;
15131 }
15132
15133 mutex_exit(&dtrace_provider_lock);
15134
15135 if (pvp == NULL)
15136 return (ESRCH);
15137
15138 bcopy(&pvp->dtpv_priv, &pvd.dtvd_priv, sizeof (dtrace_ppriv_t));
15139 bcopy(&pvp->dtpv_attr, &pvd.dtvd_attr, sizeof (dtrace_pattr_t));
15140 if (copyout(&pvd, (void *)arg, sizeof (pvd)) != 0)
15141 return (EFAULT);
15142
15143 return (0);
15144 }
15145
15146 case DTRACEIOC_EPROBE: {
15147 dtrace_eprobedesc_t epdesc;
15148 dtrace_ecb_t *ecb;
15149 dtrace_action_t *act;
15150 void *buf;
15151 size_t size;
15152 uintptr_t dest;
15153 int nrecs;
15154
15155 if (copyin((void *)arg, &epdesc, sizeof (epdesc)) != 0)
15156 return (EFAULT);
15157
15158 mutex_enter(&dtrace_lock);
15159
15160 if ((ecb = dtrace_epid2ecb(state, epdesc.dtepd_epid)) == NULL) {
15161 mutex_exit(&dtrace_lock);
15162 return (EINVAL);
15163 }
15164
15165 if (ecb->dte_probe == NULL) {
15166 mutex_exit(&dtrace_lock);
15167 return (EINVAL);
15168 }
15169
15170 epdesc.dtepd_probeid = ecb->dte_probe->dtpr_id;
15171 epdesc.dtepd_uarg = ecb->dte_uarg;
15172 epdesc.dtepd_size = ecb->dte_size;
15173
15174 nrecs = epdesc.dtepd_nrecs;
15175 epdesc.dtepd_nrecs = 0;
15176 for (act = ecb->dte_action; act != NULL; act = act->dta_next) {
15177 if (DTRACEACT_ISAGG(act->dta_kind) || act->dta_intuple)
15178 continue;
15179
15180 epdesc.dtepd_nrecs++;
15181 }
15182
15183 /*
15184 * Now that we have the size, we need to allocate a temporary
15185 * buffer in which to store the complete description. We need
15186 * the temporary buffer to be able to drop dtrace_lock()
15187 * across the copyout(), below.
15188 */
15189 size = sizeof (dtrace_eprobedesc_t) +
15190 (epdesc.dtepd_nrecs * sizeof (dtrace_recdesc_t));
15191
15192 buf = kmem_alloc(size, KM_SLEEP);
15193 dest = (uintptr_t)buf;
15194
15195 bcopy(&epdesc, (void *)dest, sizeof (epdesc));
15196 dest += offsetof(dtrace_eprobedesc_t, dtepd_rec[0]);
15197
15198 for (act = ecb->dte_action; act != NULL; act = act->dta_next) {
15199 if (DTRACEACT_ISAGG(act->dta_kind) || act->dta_intuple)
15200 continue;
15201
15202 if (nrecs-- == 0)
15203 break;
15204
15205 bcopy(&act->dta_rec, (void *)dest,
15206 sizeof (dtrace_recdesc_t));
15207 dest += sizeof (dtrace_recdesc_t);
15208 }
15209
15210 mutex_exit(&dtrace_lock);
15211
15212 if (copyout(buf, (void *)arg, dest - (uintptr_t)buf) != 0) {
15213 kmem_free(buf, size);
15214 return (EFAULT);
15215 }
15216
15217 kmem_free(buf, size);
15218 return (0);
15219 }
15220
15221 case DTRACEIOC_AGGDESC: {
15222 dtrace_aggdesc_t aggdesc;
15223 dtrace_action_t *act;
15224 dtrace_aggregation_t *agg;
15225 int nrecs;
15226 uint32_t offs;
15227 dtrace_recdesc_t *lrec;
15228 void *buf;
15229 size_t size;
15230 uintptr_t dest;
15231
15232 if (copyin((void *)arg, &aggdesc, sizeof (aggdesc)) != 0)
15233 return (EFAULT);
15234
15235 mutex_enter(&dtrace_lock);
15236
15237 if ((agg = dtrace_aggid2agg(state, aggdesc.dtagd_id)) == NULL) {
15238 mutex_exit(&dtrace_lock);
15239 return (EINVAL);
15240 }
15241
15242 aggdesc.dtagd_epid = agg->dtag_ecb->dte_epid;
15243
15244 nrecs = aggdesc.dtagd_nrecs;
15245 aggdesc.dtagd_nrecs = 0;
15246
15247 offs = agg->dtag_base;
15248 lrec = &agg->dtag_action.dta_rec;
15249 aggdesc.dtagd_size = lrec->dtrd_offset + lrec->dtrd_size - offs;
15250
15251 for (act = agg->dtag_first; ; act = act->dta_next) {
15252 ASSERT(act->dta_intuple ||
15253 DTRACEACT_ISAGG(act->dta_kind));
15254
15255 /*
15256 * If this action has a record size of zero, it
15257 * denotes an argument to the aggregating action.
15258 * Because the presence of this record doesn't (or
15259 * shouldn't) affect the way the data is interpreted,
15260 * we don't copy it out to save user-level the
15261 * confusion of dealing with a zero-length record.
15262 */
15263 if (act->dta_rec.dtrd_size == 0) {
15264 ASSERT(agg->dtag_hasarg);
15265 continue;
15266 }
15267
15268 aggdesc.dtagd_nrecs++;
15269
15270 if (act == &agg->dtag_action)
15271 break;
15272 }
15273
15274 /*
15275 * Now that we have the size, we need to allocate a temporary
15276 * buffer in which to store the complete description. We need
15277 * the temporary buffer to be able to drop dtrace_lock()
15278 * across the copyout(), below.
15279 */
15280 size = sizeof (dtrace_aggdesc_t) +
15281 (aggdesc.dtagd_nrecs * sizeof (dtrace_recdesc_t));
15282
15283 buf = kmem_alloc(size, KM_SLEEP);
15284 dest = (uintptr_t)buf;
15285
15286 bcopy(&aggdesc, (void *)dest, sizeof (aggdesc));
15287 dest += offsetof(dtrace_aggdesc_t, dtagd_rec[0]);
15288
15289 for (act = agg->dtag_first; ; act = act->dta_next) {
15290 dtrace_recdesc_t rec = act->dta_rec;
15291
15292 /*
15293 * See the comment in the above loop for why we pass
15294 * over zero-length records.
15295 */
15296 if (rec.dtrd_size == 0) {
15297 ASSERT(agg->dtag_hasarg);
15298 continue;
15299 }
15300
15301 if (nrecs-- == 0)
15302 break;
15303
15304 rec.dtrd_offset -= offs;
15305 bcopy(&rec, (void *)dest, sizeof (rec));
15306 dest += sizeof (dtrace_recdesc_t);
15307
15308 if (act == &agg->dtag_action)
15309 break;
15310 }
15311
15312 mutex_exit(&dtrace_lock);
15313
15314 if (copyout(buf, (void *)arg, dest - (uintptr_t)buf) != 0) {
15315 kmem_free(buf, size);
15316 return (EFAULT);
15317 }
15318
15319 kmem_free(buf, size);
15320 return (0);
15321 }
15322
15323 case DTRACEIOC_ENABLE: {
15324 dof_hdr_t *dof;
15325 dtrace_enabling_t *enab = NULL;
15326 dtrace_vstate_t *vstate;
15327 int err = 0;
15328
15329 *rv = 0;
15330
15331 /*
15332 * If a NULL argument has been passed, we take this as our
15333 * cue to reevaluate our enablings.
15334 */
15335 if (arg == NULL) {
15336 dtrace_enabling_matchall();
15337
15338 return (0);
15339 }
15340
15341 if ((dof = dtrace_dof_copyin(arg, &rval)) == NULL)
15342 return (rval);
15343
15344 mutex_enter(&cpu_lock);
15345 mutex_enter(&dtrace_lock);
15346 vstate = &state->dts_vstate;
15347
15348 if (state->dts_activity != DTRACE_ACTIVITY_INACTIVE) {
15349 mutex_exit(&dtrace_lock);
15350 mutex_exit(&cpu_lock);
15351 dtrace_dof_destroy(dof);
15352 return (EBUSY);
15353 }
15354
15355 if (dtrace_dof_slurp(dof, vstate, cr, &enab, 0, B_TRUE) != 0) {
15356 mutex_exit(&dtrace_lock);
15357 mutex_exit(&cpu_lock);
15358 dtrace_dof_destroy(dof);
15359 return (EINVAL);
15360 }
15361
15362 if ((rval = dtrace_dof_options(dof, state)) != 0) {
15363 dtrace_enabling_destroy(enab);
15364 mutex_exit(&dtrace_lock);
15365 mutex_exit(&cpu_lock);
15366 dtrace_dof_destroy(dof);
15367 return (rval);
15368 }
15369
15370 if ((err = dtrace_enabling_match(enab, rv)) == 0) {
15371 err = dtrace_enabling_retain(enab);
15372 } else {
15373 dtrace_enabling_destroy(enab);
15374 }
15375
15376 mutex_exit(&cpu_lock);
15377 mutex_exit(&dtrace_lock);
15378 dtrace_dof_destroy(dof);
15379
15380 return (err);
15381 }
15382
15383 case DTRACEIOC_REPLICATE: {
15384 dtrace_repldesc_t desc;
15385 dtrace_probedesc_t *match = &desc.dtrpd_match;
15386 dtrace_probedesc_t *create = &desc.dtrpd_create;
15387 int err;
15388
15389 if (copyin((void *)arg, &desc, sizeof (desc)) != 0)
15390 return (EFAULT);
15391
15392 match->dtpd_provider[DTRACE_PROVNAMELEN - 1] = '\0';
15393 match->dtpd_mod[DTRACE_MODNAMELEN - 1] = '\0';
15394 match->dtpd_func[DTRACE_FUNCNAMELEN - 1] = '\0';
15395 match->dtpd_name[DTRACE_NAMELEN - 1] = '\0';
15396
15397 create->dtpd_provider[DTRACE_PROVNAMELEN - 1] = '\0';
15398 create->dtpd_mod[DTRACE_MODNAMELEN - 1] = '\0';
15399 create->dtpd_func[DTRACE_FUNCNAMELEN - 1] = '\0';
15400 create->dtpd_name[DTRACE_NAMELEN - 1] = '\0';
15401
15402 mutex_enter(&dtrace_lock);
15403 err = dtrace_enabling_replicate(state, match, create);
15404 mutex_exit(&dtrace_lock);
15405
15406 return (err);
15407 }
15408
15409 case DTRACEIOC_PROBEMATCH:
15410 case DTRACEIOC_PROBES: {
15411 dtrace_probe_t *probe = NULL;
15412 dtrace_probedesc_t desc;
15413 dtrace_probekey_t pkey;
15414 dtrace_id_t i;
15415 int m = 0;
15416 uint32_t priv;
15417 uid_t uid;
15418 zoneid_t zoneid;
15419
15420 if (copyin((void *)arg, &desc, sizeof (desc)) != 0)
15421 return (EFAULT);
15422
15423 desc.dtpd_provider[DTRACE_PROVNAMELEN - 1] = '\0';
15424 desc.dtpd_mod[DTRACE_MODNAMELEN - 1] = '\0';
15425 desc.dtpd_func[DTRACE_FUNCNAMELEN - 1] = '\0';
15426 desc.dtpd_name[DTRACE_NAMELEN - 1] = '\0';
15427
15428 /*
15429 * Before we attempt to match this probe, we want to give
15430 * all providers the opportunity to provide it.
15431 */
15432 if (desc.dtpd_id == DTRACE_IDNONE) {
15433 mutex_enter(&dtrace_provider_lock);
15434 dtrace_probe_provide(&desc, NULL);
15435 mutex_exit(&dtrace_provider_lock);
15436 desc.dtpd_id++;
15437 }
15438
15439 if (cmd == DTRACEIOC_PROBEMATCH) {
15440 dtrace_probekey(&desc, &pkey);
15441 pkey.dtpk_id = DTRACE_IDNONE;
15442 }
15443
15444 dtrace_cred2priv(cr, &priv, &uid, &zoneid);
15445
15446 mutex_enter(&dtrace_lock);
15447
15448 if (cmd == DTRACEIOC_PROBEMATCH) {
15449 for (i = desc.dtpd_id; i <= dtrace_nprobes; i++) {
15450 if ((probe = dtrace_probes[i - 1]) != NULL &&
15451 (m = dtrace_match_probe(probe, &pkey,
15452 priv, uid, zoneid)) != 0)
15453 break;
15454 }
15455
15456 if (m < 0) {
15457 mutex_exit(&dtrace_lock);
15458 return (EINVAL);
15459 }
15460
15461 } else {
15462 for (i = desc.dtpd_id; i <= dtrace_nprobes; i++) {
15463 if ((probe = dtrace_probes[i - 1]) != NULL &&
15464 dtrace_match_priv(probe, priv, uid, zoneid))
15465 break;
15466 }
15467 }
15468
15469 if (probe == NULL) {
15470 mutex_exit(&dtrace_lock);
15471 return (ESRCH);
15472 }
15473
15474 dtrace_probe_description(probe, &desc);
15475 mutex_exit(&dtrace_lock);
15476
15477 if (copyout(&desc, (void *)arg, sizeof (desc)) != 0)
15478 return (EFAULT);
15479
15480 return (0);
15481 }
15482
15483 case DTRACEIOC_PROBEARG: {
15484 dtrace_argdesc_t desc;
15485 dtrace_probe_t *probe;
15486 dtrace_provider_t *prov;
15487
15488 if (copyin((void *)arg, &desc, sizeof (desc)) != 0)
15489 return (EFAULT);
15490
15491 if (desc.dtargd_id == DTRACE_IDNONE)
15492 return (EINVAL);
15493
15494 if (desc.dtargd_ndx == DTRACE_ARGNONE)
15495 return (EINVAL);
15496
15497 mutex_enter(&dtrace_provider_lock);
15498 mutex_enter(&mod_lock);
15499 mutex_enter(&dtrace_lock);
15500
15501 if (desc.dtargd_id > dtrace_nprobes) {
15502 mutex_exit(&dtrace_lock);
15503 mutex_exit(&mod_lock);
15504 mutex_exit(&dtrace_provider_lock);
15505 return (EINVAL);
15506 }
15507
15508 if ((probe = dtrace_probes[desc.dtargd_id - 1]) == NULL) {
15509 mutex_exit(&dtrace_lock);
15510 mutex_exit(&mod_lock);
15511 mutex_exit(&dtrace_provider_lock);
15512 return (EINVAL);
15513 }
15514
15515 mutex_exit(&dtrace_lock);
15516
15517 prov = probe->dtpr_provider;
15518
15519 if (prov->dtpv_pops.dtps_getargdesc == NULL) {
15520 /*
15521 * There isn't any typed information for this probe.
15522 * Set the argument number to DTRACE_ARGNONE.
15523 */
15524 desc.dtargd_ndx = DTRACE_ARGNONE;
15525 } else {
15526 desc.dtargd_native[0] = '\0';
15527 desc.dtargd_xlate[0] = '\0';
15528 desc.dtargd_mapping = desc.dtargd_ndx;
15529
15530 prov->dtpv_pops.dtps_getargdesc(prov->dtpv_arg,
15531 probe->dtpr_id, probe->dtpr_arg, &desc);
15532 }
15533
15534 mutex_exit(&mod_lock);
15535 mutex_exit(&dtrace_provider_lock);
15536
15537 if (copyout(&desc, (void *)arg, sizeof (desc)) != 0)
15538 return (EFAULT);
15539
15540 return (0);
15541 }
15542
15543 case DTRACEIOC_GO: {
15544 processorid_t cpuid;
15545 rval = dtrace_state_go(state, &cpuid);
15546
15547 if (rval != 0)
15548 return (rval);
15549
15550 if (copyout(&cpuid, (void *)arg, sizeof (cpuid)) != 0)
15551 return (EFAULT);
15552
15553 return (0);
15554 }
15555
15556 case DTRACEIOC_STOP: {
15557 processorid_t cpuid;
15558
15559 mutex_enter(&dtrace_lock);
15560 rval = dtrace_state_stop(state, &cpuid);
15561 mutex_exit(&dtrace_lock);
15562
15563 if (rval != 0)
15564 return (rval);
15565
15566 if (copyout(&cpuid, (void *)arg, sizeof (cpuid)) != 0)
15567 return (EFAULT);
15568
15569 return (0);
15570 }
15571
15572 case DTRACEIOC_DOFGET: {
15573 dof_hdr_t hdr, *dof;
15574 uint64_t len;
15575
15576 if (copyin((void *)arg, &hdr, sizeof (hdr)) != 0)
15577 return (EFAULT);
15578
15579 mutex_enter(&dtrace_lock);
15580 dof = dtrace_dof_create(state);
15581 mutex_exit(&dtrace_lock);
15582
15583 len = MIN(hdr.dofh_loadsz, dof->dofh_loadsz);
15584 rval = copyout(dof, (void *)arg, len);
15585 dtrace_dof_destroy(dof);
15586
15587 return (rval == 0 ? 0 : EFAULT);
15588 }
15589
15590 case DTRACEIOC_AGGSNAP:
15591 case DTRACEIOC_BUFSNAP: {
15592 dtrace_bufdesc_t desc;
15593 caddr_t cached;
15594 dtrace_buffer_t *buf;
15595
15596 if (copyin((void *)arg, &desc, sizeof (desc)) != 0)
15597 return (EFAULT);
15598
15599 if (desc.dtbd_cpu < 0 || desc.dtbd_cpu >= NCPU)
15600 return (EINVAL);
15601
15602 mutex_enter(&dtrace_lock);
15603
15604 if (cmd == DTRACEIOC_BUFSNAP) {
15605 buf = &state->dts_buffer[desc.dtbd_cpu];
15606 } else {
15607 buf = &state->dts_aggbuffer[desc.dtbd_cpu];
15608 }
15609
15610 if (buf->dtb_flags & (DTRACEBUF_RING | DTRACEBUF_FILL)) {
15611 size_t sz = buf->dtb_offset;
15612
15613 if (state->dts_activity != DTRACE_ACTIVITY_STOPPED) {
15614 mutex_exit(&dtrace_lock);
15615 return (EBUSY);
15616 }
15617
15618 /*
15619 * If this buffer has already been consumed, we're
15620 * going to indicate that there's nothing left here
15621 * to consume.
15622 */
15623 if (buf->dtb_flags & DTRACEBUF_CONSUMED) {
15624 mutex_exit(&dtrace_lock);
15625
15626 desc.dtbd_size = 0;
15627 desc.dtbd_drops = 0;
15628 desc.dtbd_errors = 0;
15629 desc.dtbd_oldest = 0;
15630 sz = sizeof (desc);
15631
15632 if (copyout(&desc, (void *)arg, sz) != 0)
15633 return (EFAULT);
15634
15635 return (0);
15636 }
15637
15638 /*
15639 * If this is a ring buffer that has wrapped, we want
15640 * to copy the whole thing out.
15641 */
15642 if (buf->dtb_flags & DTRACEBUF_WRAPPED) {
15643 dtrace_buffer_polish(buf);
15644 sz = buf->dtb_size;
15645 }
15646
15647 if (copyout(buf->dtb_tomax, desc.dtbd_data, sz) != 0) {
15648 mutex_exit(&dtrace_lock);
15649 return (EFAULT);
15650 }
15651
15652 desc.dtbd_size = sz;
15653 desc.dtbd_drops = buf->dtb_drops;
15654 desc.dtbd_errors = buf->dtb_errors;
15655 desc.dtbd_oldest = buf->dtb_xamot_offset;
15656 desc.dtbd_timestamp = dtrace_gethrtime();
15657
15658 mutex_exit(&dtrace_lock);
15659
15660 if (copyout(&desc, (void *)arg, sizeof (desc)) != 0)
15661 return (EFAULT);
15662
15663 buf->dtb_flags |= DTRACEBUF_CONSUMED;
15664
15665 return (0);
15666 }
15667
15668 if (buf->dtb_tomax == NULL) {
15669 ASSERT(buf->dtb_xamot == NULL);
15670 mutex_exit(&dtrace_lock);
15671 return (ENOENT);
15672 }
15673
15674 cached = buf->dtb_tomax;
15675 ASSERT(!(buf->dtb_flags & DTRACEBUF_NOSWITCH));
15676
15677 dtrace_xcall(desc.dtbd_cpu,
15678 (dtrace_xcall_t)dtrace_buffer_switch, buf);
15679
15680 state->dts_errors += buf->dtb_xamot_errors;
15681
15682 /*
15683 * If the buffers did not actually switch, then the cross call
15684 * did not take place -- presumably because the given CPU is
15685 * not in the ready set. If this is the case, we'll return
15686 * ENOENT.
15687 */
15688 if (buf->dtb_tomax == cached) {
15689 ASSERT(buf->dtb_xamot != cached);
15690 mutex_exit(&dtrace_lock);
15691 return (ENOENT);
15692 }
15693
15694 ASSERT(cached == buf->dtb_xamot);
15695
15696 /*
15697 * We have our snapshot; now copy it out.
15698 */
15699 if (copyout(buf->dtb_xamot, desc.dtbd_data,
15700 buf->dtb_xamot_offset) != 0) {
15701 mutex_exit(&dtrace_lock);
15702 return (EFAULT);
15703 }
15704
15705 desc.dtbd_size = buf->dtb_xamot_offset;
15706 desc.dtbd_drops = buf->dtb_xamot_drops;
15707 desc.dtbd_errors = buf->dtb_xamot_errors;
15708 desc.dtbd_oldest = 0;
15709 desc.dtbd_timestamp = buf->dtb_switched;
15710
15711 mutex_exit(&dtrace_lock);
15712
15713 /*
15714 * Finally, copy out the buffer description.
15715 */
15716 if (copyout(&desc, (void *)arg, sizeof (desc)) != 0)
15717 return (EFAULT);
15718
15719 return (0);
15720 }
15721
15722 case DTRACEIOC_CONF: {
15723 dtrace_conf_t conf;
15724
15725 bzero(&conf, sizeof (conf));
15726 conf.dtc_difversion = DIF_VERSION;
15727 conf.dtc_difintregs = DIF_DIR_NREGS;
15728 conf.dtc_diftupregs = DIF_DTR_NREGS;
15729 conf.dtc_ctfmodel = CTF_MODEL_NATIVE;
15730
15731 if (copyout(&conf, (void *)arg, sizeof (conf)) != 0)
15732 return (EFAULT);
15733
15734 return (0);
15735 }
15736
15737 case DTRACEIOC_STATUS: {
15738 dtrace_status_t stat;
15739 dtrace_dstate_t *dstate;
15740 int i, j;
15741 uint64_t nerrs;
15742
15743 /*
15744 * See the comment in dtrace_state_deadman() for the reason
15745 * for setting dts_laststatus to INT64_MAX before setting
15746 * it to the correct value.
15747 */
15748 state->dts_laststatus = INT64_MAX;
15749 dtrace_membar_producer();
15750 state->dts_laststatus = dtrace_gethrtime();
15751
15752 bzero(&stat, sizeof (stat));
15753
15754 mutex_enter(&dtrace_lock);
15755
15756 if (state->dts_activity == DTRACE_ACTIVITY_INACTIVE) {
15757 mutex_exit(&dtrace_lock);
15758 return (ENOENT);
15759 }
15760
15761 if (state->dts_activity == DTRACE_ACTIVITY_DRAINING)
15762 stat.dtst_exiting = 1;
15763
15764 nerrs = state->dts_errors;
15765 dstate = &state->dts_vstate.dtvs_dynvars;
15766
15767 for (i = 0; i < NCPU; i++) {
15768 dtrace_dstate_percpu_t *dcpu = &dstate->dtds_percpu[i];
15769
15770 stat.dtst_dyndrops += dcpu->dtdsc_drops;
15771 stat.dtst_dyndrops_dirty += dcpu->dtdsc_dirty_drops;
15772 stat.dtst_dyndrops_rinsing += dcpu->dtdsc_rinsing_drops;
15773
15774 if (state->dts_buffer[i].dtb_flags & DTRACEBUF_FULL)
15775 stat.dtst_filled++;
15776
15777 nerrs += state->dts_buffer[i].dtb_errors;
15778
15779 for (j = 0; j < state->dts_nspeculations; j++) {
15780 dtrace_speculation_t *spec;
15781 dtrace_buffer_t *buf;
15782
15783 spec = &state->dts_speculations[j];
15784 buf = &spec->dtsp_buffer[i];
15785 stat.dtst_specdrops += buf->dtb_xamot_drops;
15786 }
15787 }
15788
15789 stat.dtst_specdrops_busy = state->dts_speculations_busy;
15790 stat.dtst_specdrops_unavail = state->dts_speculations_unavail;
15791 stat.dtst_stkstroverflows = state->dts_stkstroverflows;
15792 stat.dtst_dblerrors = state->dts_dblerrors;
15793 stat.dtst_killed =
15794 (state->dts_activity == DTRACE_ACTIVITY_KILLED);
15795 stat.dtst_errors = nerrs;
15796
15797 mutex_exit(&dtrace_lock);
15798
15799 if (copyout(&stat, (void *)arg, sizeof (stat)) != 0)
15800 return (EFAULT);
15801
15802 return (0);
15803 }
15804
15805 case DTRACEIOC_FORMAT: {
15806 dtrace_fmtdesc_t fmt;
15807 char *str;
15808 int len;
15809
15810 if (copyin((void *)arg, &fmt, sizeof (fmt)) != 0)
15811 return (EFAULT);
15812
15813 mutex_enter(&dtrace_lock);
15814
15815 if (fmt.dtfd_format == 0 ||
15816 fmt.dtfd_format > state->dts_nformats) {
15817 mutex_exit(&dtrace_lock);
15818 return (EINVAL);
15819 }
15820
15821 /*
15822 * Format strings are allocated contiguously and they are
15823 * never freed; if a format index is less than the number
15824 * of formats, we can assert that the format map is non-NULL
15825 * and that the format for the specified index is non-NULL.
15826 */
15827 ASSERT(state->dts_formats != NULL);
15828 str = state->dts_formats[fmt.dtfd_format - 1];
15829 ASSERT(str != NULL);
15830
15831 len = strlen(str) + 1;
15832
15833 if (len > fmt.dtfd_length) {
15834 fmt.dtfd_length = len;
15835
15836 if (copyout(&fmt, (void *)arg, sizeof (fmt)) != 0) {
15837 mutex_exit(&dtrace_lock);
15838 return (EINVAL);
15839 }
15840 } else {
15841 if (copyout(str, fmt.dtfd_string, len) != 0) {
15842 mutex_exit(&dtrace_lock);
15843 return (EINVAL);
15844 }
15845 }
15846
15847 mutex_exit(&dtrace_lock);
15848 return (0);
15849 }
15850
15851 default:
15852 break;
15853 }
15854
15855 return (ENOTTY);
15856 }
15857
15858 /*ARGSUSED*/
15859 static int
15860 dtrace_detach(dev_info_t *dip, ddi_detach_cmd_t cmd)
15861 {
15862 dtrace_state_t *state;
15863
15864 switch (cmd) {
15865 case DDI_DETACH:
15866 break;
15867
15868 case DDI_SUSPEND:
15869 return (DDI_SUCCESS);
15870
15871 default:
15872 return (DDI_FAILURE);
15873 }
15874
15875 mutex_enter(&cpu_lock);
15876 mutex_enter(&dtrace_provider_lock);
15877 mutex_enter(&dtrace_lock);
15878
15879 ASSERT(dtrace_opens == 0);
15880
15881 if (dtrace_helpers > 0) {
15882 mutex_exit(&dtrace_provider_lock);
15883 mutex_exit(&dtrace_lock);
15884 mutex_exit(&cpu_lock);
15885 return (DDI_FAILURE);
15886 }
15887
15888 if (dtrace_unregister((dtrace_provider_id_t)dtrace_provider) != 0) {
15889 mutex_exit(&dtrace_provider_lock);
15890 mutex_exit(&dtrace_lock);
15891 mutex_exit(&cpu_lock);
15892 return (DDI_FAILURE);
15893 }
15894
15895 dtrace_provider = NULL;
15896
15897 if ((state = dtrace_anon_grab()) != NULL) {
15898 /*
15899 * If there were ECBs on this state, the provider should
15900 * have not been allowed to detach; assert that there is
15901 * none.
15902 */
15903 ASSERT(state->dts_necbs == 0);
15904 dtrace_state_destroy(state);
15905
15906 /*
15907 * If we're being detached with anonymous state, we need to
15908 * indicate to the kernel debugger that DTrace is now inactive.
15909 */
15910 (void) kdi_dtrace_set(KDI_DTSET_DTRACE_DEACTIVATE);
15911 }
15912
15913 bzero(&dtrace_anon, sizeof (dtrace_anon_t));
15914 unregister_cpu_setup_func((cpu_setup_func_t *)dtrace_cpu_setup, NULL);
15915 dtrace_cpu_init = NULL;
15916 dtrace_helpers_cleanup = NULL;
15917 dtrace_helpers_fork = NULL;
15918 dtrace_cpustart_init = NULL;
15919 dtrace_cpustart_fini = NULL;
15920 dtrace_debugger_init = NULL;
15921 dtrace_debugger_fini = NULL;
15922 dtrace_modload = NULL;
15923 dtrace_modunload = NULL;
15924
15925 mutex_exit(&cpu_lock);
15926
15927 if (dtrace_helptrace_enabled) {
15928 kmem_free(dtrace_helptrace_buffer, dtrace_helptrace_bufsize);
15929 dtrace_helptrace_buffer = NULL;
15930 }
15931
15932 kmem_free(dtrace_probes, dtrace_nprobes * sizeof (dtrace_probe_t *));
15933 dtrace_probes = NULL;
15934 dtrace_nprobes = 0;
15935
15936 dtrace_hash_destroy(dtrace_bymod);
15937 dtrace_hash_destroy(dtrace_byfunc);
15938 dtrace_hash_destroy(dtrace_byname);
15939 dtrace_bymod = NULL;
15940 dtrace_byfunc = NULL;
15941 dtrace_byname = NULL;
15942
15943 kmem_cache_destroy(dtrace_state_cache);
15944 vmem_destroy(dtrace_minor);
15945 vmem_destroy(dtrace_arena);
15946
15947 if (dtrace_toxrange != NULL) {
15948 kmem_free(dtrace_toxrange,
15949 dtrace_toxranges_max * sizeof (dtrace_toxrange_t));
15950 dtrace_toxrange = NULL;
15951 dtrace_toxranges = 0;
15952 dtrace_toxranges_max = 0;
15953 }
15954
15955 ddi_remove_minor_node(dtrace_devi, NULL);
15956 dtrace_devi = NULL;
15957
15958 ddi_soft_state_fini(&dtrace_softstate);
15959
15960 ASSERT(dtrace_vtime_references == 0);
15961 ASSERT(dtrace_opens == 0);
15962 ASSERT(dtrace_retained == NULL);
15963
15964 mutex_exit(&dtrace_lock);
15965 mutex_exit(&dtrace_provider_lock);
15966
15967 /*
15968 * We don't destroy the task queue until after we have dropped our
15969 * locks (taskq_destroy() may block on running tasks). To prevent
15970 * attempting to do work after we have effectively detached but before
15971 * the task queue has been destroyed, all tasks dispatched via the
15972 * task queue must check that DTrace is still attached before
15973 * performing any operation.
15974 */
15975 taskq_destroy(dtrace_taskq);
15976 dtrace_taskq = NULL;
15977
15978 return (DDI_SUCCESS);
15979 }
15980
15981 /*ARGSUSED*/
15982 static int
15983 dtrace_info(dev_info_t *dip, ddi_info_cmd_t infocmd, void *arg, void **result)
15984 {
15985 int error;
15986
15987 switch (infocmd) {
15988 case DDI_INFO_DEVT2DEVINFO:
15989 *result = (void *)dtrace_devi;
15990 error = DDI_SUCCESS;
15991 break;
15992 case DDI_INFO_DEVT2INSTANCE:
15993 *result = (void *)0;
15994 error = DDI_SUCCESS;
15995 break;
15996 default:
15997 error = DDI_FAILURE;
15998 }
15999 return (error);
16000 }
16001
16002 static struct cb_ops dtrace_cb_ops = {
16003 dtrace_open, /* open */
16004 dtrace_close, /* close */
16005 nulldev, /* strategy */
16006 nulldev, /* print */
16007 nodev, /* dump */
16008 nodev, /* read */
16009 nodev, /* write */
16010 dtrace_ioctl, /* ioctl */
16011 nodev, /* devmap */
16012 nodev, /* mmap */
16013 nodev, /* segmap */
16014 nochpoll, /* poll */
16015 ddi_prop_op, /* cb_prop_op */
16016 0, /* streamtab */
16017 D_NEW | D_MP /* Driver compatibility flag */
16018 };
16019
16020 static struct dev_ops dtrace_ops = {
16021 DEVO_REV, /* devo_rev */
16022 0, /* refcnt */
16023 dtrace_info, /* get_dev_info */
16024 nulldev, /* identify */
16025 nulldev, /* probe */
16026 dtrace_attach, /* attach */
16027 dtrace_detach, /* detach */
16028 nodev, /* reset */
16029 &dtrace_cb_ops, /* driver operations */
16030 NULL, /* bus operations */
16031 nodev, /* dev power */
16032 ddi_quiesce_not_needed, /* quiesce */
16033 };
16034
16035 static struct modldrv modldrv = {
16036 &mod_driverops, /* module type (this is a pseudo driver) */
16037 "Dynamic Tracing", /* name of module */
16038 &dtrace_ops, /* driver ops */
16039 };
16040
16041 static struct modlinkage modlinkage = {
16042 MODREV_1,
16043 (void *)&modldrv,
16044 NULL
16045 };
16046
16047 int
16048 _init(void)
16049 {
16050 return (mod_install(&modlinkage));
16051 }
16052
16053 int
16054 _info(struct modinfo *modinfop)
16055 {
16056 return (mod_info(&modlinkage, modinfop));
16057 }
16058
16059 int
16060 _fini(void)
16061 {
16062 return (mod_remove(&modlinkage));
16063 }