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) 2011, Joyent, Inc. All rights reserved.
25 */
26
27 /*
28 * DTrace - Dynamic Tracing for Solaris
29 *
30 * This is the implementation of the Solaris Dynamic Tracing framework
31 * (DTrace). The user-visible interface to DTrace is described at length in
32 * the "Solaris Dynamic Tracing Guide". The interfaces between the libdtrace
33 * library, the in-kernel DTrace framework, and the DTrace providers are
34 * described in the block comments in the <sys/dtrace.h> header file. The
35 * internal architecture of DTrace is described in the block comments in the
36 * <sys/dtrace_impl.h> header file. The comments contained within the DTrace
37 * implementation very much assume mastery of all of these sources; if one has
38 * an unanswered question about the implementation, one should consult them
39 * first.
40 *
41 * The functions here are ordered roughly as follows:
42 *
43 * - Probe context functions
44 * - Probe hashing functions
45 * - Non-probe context utility functions
46 * - Matching functions
47 * - Provider-to-Framework API functions
48 * - Probe management functions
49 * - DIF object functions
50 * - Format functions
51 * - Predicate functions
52 * - ECB functions
53 * - Buffer functions
54 * - Enabling functions
55 * - DOF functions
56 * - Anonymous enabling functions
57 * - Consumer state functions
58 * - Helper functions
59 * - Hook functions
60 * - Driver cookbook functions
61 *
62 * Each group of functions begins with a block comment labelled the "DTrace
63 * [Group] Functions", allowing one to find each block by searching forward
64 * on capital-f functions.
65 */
66 #include <sys/errno.h>
67 #include <sys/stat.h>
68 #include <sys/modctl.h>
69 #include <sys/conf.h>
70 #include <sys/systm.h>
71 #include <sys/ddi.h>
72 #include <sys/sunddi.h>
73 #include <sys/cpuvar.h>
74 #include <sys/kmem.h>
75 #include <sys/strsubr.h>
76 #include <sys/sysmacros.h>
77 #include <sys/dtrace_impl.h>
78 #include <sys/atomic.h>
79 #include <sys/cmn_err.h>
80 #include <sys/mutex_impl.h>
81 #include <sys/rwlock_impl.h>
82 #include <sys/ctf_api.h>
83 #include <sys/panic.h>
84 #include <sys/priv_impl.h>
85 #include <sys/policy.h>
86 #include <sys/cred_impl.h>
87 #include <sys/procfs_isa.h>
88 #include <sys/taskq.h>
89 #include <sys/mkdev.h>
90 #include <sys/kdi.h>
91 #include <sys/zone.h>
92 #include <sys/socket.h>
93 #include <netinet/in.h>
94
95 /*
96 * DTrace Tunable Variables
97 *
98 * The following variables may be tuned by adding a line to /etc/system that
99 * includes both the name of the DTrace module ("dtrace") and the name of the
100 * variable. For example:
101 *
102 * set dtrace:dtrace_destructive_disallow = 1
103 *
104 * In general, the only variables that one should be tuning this way are those
105 * that affect system-wide DTrace behavior, and for which the default behavior
106 * is undesirable. Most of these variables are tunable on a per-consumer
107 * basis using DTrace options, and need not be tuned on a system-wide basis.
108 * When tuning these variables, avoid pathological values; while some attempt
109 * is made to verify the integrity of these variables, they are not considered
110 * part of the supported interface to DTrace, and they are therefore not
111 * checked comprehensively. Further, these variables should not be tuned
112 * dynamically via "mdb -kw" or other means; they should only be tuned via
113 * /etc/system.
114 */
115 int dtrace_destructive_disallow = 0;
116 dtrace_optval_t dtrace_nonroot_maxsize = (16 * 1024 * 1024);
117 size_t dtrace_difo_maxsize = (256 * 1024);
118 dtrace_optval_t dtrace_dof_maxsize = (256 * 1024);
119 size_t dtrace_global_maxsize = (16 * 1024);
120 size_t dtrace_actions_max = (16 * 1024);
121 size_t dtrace_retain_max = 1024;
122 dtrace_optval_t dtrace_helper_actions_max = 1024;
123 dtrace_optval_t dtrace_helper_providers_max = 32;
124 dtrace_optval_t dtrace_dstate_defsize = (1 * 1024 * 1024);
125 size_t dtrace_strsize_default = 256;
126 dtrace_optval_t dtrace_cleanrate_default = 9900990; /* 101 hz */
127 dtrace_optval_t dtrace_cleanrate_min = 200000; /* 5000 hz */
128 dtrace_optval_t dtrace_cleanrate_max = (uint64_t)60 * NANOSEC; /* 1/minute */
129 dtrace_optval_t dtrace_aggrate_default = NANOSEC; /* 1 hz */
130 dtrace_optval_t dtrace_statusrate_default = NANOSEC; /* 1 hz */
131 dtrace_optval_t dtrace_statusrate_max = (hrtime_t)10 * NANOSEC; /* 6/minute */
132 dtrace_optval_t dtrace_switchrate_default = NANOSEC; /* 1 hz */
133 dtrace_optval_t dtrace_nspec_default = 1;
134 dtrace_optval_t dtrace_specsize_default = 32 * 1024;
135 dtrace_optval_t dtrace_stackframes_default = 20;
136 dtrace_optval_t dtrace_ustackframes_default = 20;
137 dtrace_optval_t dtrace_jstackframes_default = 50;
138 dtrace_optval_t dtrace_jstackstrsize_default = 512;
139 int dtrace_msgdsize_max = 128;
140 hrtime_t dtrace_chill_max = 500 * (NANOSEC / MILLISEC); /* 500 ms */
141 hrtime_t dtrace_chill_interval = NANOSEC; /* 1000 ms */
142 int dtrace_devdepth_max = 32;
143 int dtrace_err_verbose;
144 hrtime_t dtrace_deadman_interval = NANOSEC;
145 hrtime_t dtrace_deadman_timeout = (hrtime_t)10 * NANOSEC;
146 hrtime_t dtrace_deadman_user = (hrtime_t)30 * NANOSEC;
147 hrtime_t dtrace_unregister_defunct_reap = (hrtime_t)60 * NANOSEC;
148
149 /*
150 * DTrace External Variables
151 *
152 * As dtrace(7D) is a kernel module, any DTrace variables are obviously
153 * available to DTrace consumers via the backtick (`) syntax. One of these,
154 * dtrace_zero, is made deliberately so: it is provided as a source of
155 * well-known, zero-filled memory. While this variable is not documented,
156 * it is used by some translators as an implementation detail.
157 */
158 const char dtrace_zero[256] = { 0 }; /* zero-filled memory */
159
160 /*
161 * DTrace Internal Variables
162 */
163 static dev_info_t *dtrace_devi; /* device info */
164 static vmem_t *dtrace_arena; /* probe ID arena */
165 static vmem_t *dtrace_minor; /* minor number arena */
166 static taskq_t *dtrace_taskq; /* task queue */
167 static dtrace_probe_t **dtrace_probes; /* array of all probes */
168 static int dtrace_nprobes; /* number of probes */
169 static dtrace_provider_t *dtrace_provider; /* provider list */
170 static dtrace_meta_t *dtrace_meta_pid; /* user-land meta provider */
171 static int dtrace_opens; /* number of opens */
172 static int dtrace_helpers; /* number of helpers */
173 static void *dtrace_softstate; /* softstate pointer */
174 static dtrace_hash_t *dtrace_bymod; /* probes hashed by module */
175 static dtrace_hash_t *dtrace_byfunc; /* probes hashed by function */
176 static dtrace_hash_t *dtrace_byname; /* probes hashed by name */
177 static dtrace_toxrange_t *dtrace_toxrange; /* toxic range array */
178 static int dtrace_toxranges; /* number of toxic ranges */
179 static int dtrace_toxranges_max; /* size of toxic range array */
180 static dtrace_anon_t dtrace_anon; /* anonymous enabling */
181 static kmem_cache_t *dtrace_state_cache; /* cache for dynamic state */
182 static uint64_t dtrace_vtime_references; /* number of vtimestamp refs */
183 static kthread_t *dtrace_panicked; /* panicking thread */
184 static dtrace_ecb_t *dtrace_ecb_create_cache; /* cached created ECB */
185 static dtrace_genid_t dtrace_probegen; /* current probe generation */
186 static dtrace_helpers_t *dtrace_deferred_pid; /* deferred helper list */
187 static dtrace_enabling_t *dtrace_retained; /* list of retained enablings */
188 static dtrace_genid_t dtrace_retained_gen; /* current retained enab gen */
189 static dtrace_dynvar_t dtrace_dynhash_sink; /* end of dynamic hash chains */
190 static int dtrace_dynvar_failclean; /* dynvars failed to clean */
191
192 /*
193 * DTrace Locking
194 * DTrace is protected by three (relatively coarse-grained) locks:
195 *
196 * (1) dtrace_lock is required to manipulate essentially any DTrace state,
197 * including enabling state, probes, ECBs, consumer state, helper state,
198 * etc. Importantly, dtrace_lock is _not_ required when in probe context;
199 * probe context is lock-free -- synchronization is handled via the
200 * dtrace_sync() cross call mechanism.
201 *
202 * (2) dtrace_provider_lock is required when manipulating provider state, or
203 * when provider state must be held constant.
204 *
205 * (3) dtrace_meta_lock is required when manipulating meta provider state, or
206 * when meta provider state must be held constant.
207 *
208 * The lock ordering between these three locks is dtrace_meta_lock before
209 * dtrace_provider_lock before dtrace_lock. (In particular, there are
210 * several places where dtrace_provider_lock is held by the framework as it
211 * calls into the providers -- which then call back into the framework,
212 * grabbing dtrace_lock.)
213 *
214 * There are two other locks in the mix: mod_lock and cpu_lock. With respect
215 * to dtrace_provider_lock and dtrace_lock, cpu_lock continues its historical
216 * role as a coarse-grained lock; it is acquired before both of these locks.
217 * With respect to dtrace_meta_lock, its behavior is stranger: cpu_lock must
218 * be acquired _between_ dtrace_meta_lock and any other DTrace locks.
219 * mod_lock is similar with respect to dtrace_provider_lock in that it must be
220 * acquired _between_ dtrace_provider_lock and dtrace_lock.
221 */
222 static kmutex_t dtrace_lock; /* probe state lock */
223 static kmutex_t dtrace_provider_lock; /* provider state lock */
224 static kmutex_t dtrace_meta_lock; /* meta-provider state lock */
225
226 /*
227 * DTrace Provider Variables
228 *
229 * These are the variables relating to DTrace as a provider (that is, the
230 * provider of the BEGIN, END, and ERROR probes).
231 */
232 static dtrace_pattr_t dtrace_provider_attr = {
233 { DTRACE_STABILITY_STABLE, DTRACE_STABILITY_STABLE, DTRACE_CLASS_COMMON },
234 { DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN },
235 { DTRACE_STABILITY_PRIVATE, DTRACE_STABILITY_PRIVATE, DTRACE_CLASS_UNKNOWN },
236 { DTRACE_STABILITY_STABLE, DTRACE_STABILITY_STABLE, DTRACE_CLASS_COMMON },
237 { DTRACE_STABILITY_STABLE, DTRACE_STABILITY_STABLE, DTRACE_CLASS_COMMON },
238 };
239
240 static void
241 dtrace_nullop(void)
242 {}
243
244 static int
245 dtrace_enable_nullop(void)
246 {
247 return (0);
248 }
249
250 static dtrace_pops_t dtrace_provider_ops = {
251 (void (*)(void *, const dtrace_probedesc_t *))dtrace_nullop,
252 (void (*)(void *, struct modctl *))dtrace_nullop,
253 (int (*)(void *, dtrace_id_t, void *))dtrace_enable_nullop,
254 (void (*)(void *, dtrace_id_t, void *))dtrace_nullop,
255 (void (*)(void *, dtrace_id_t, void *))dtrace_nullop,
256 (void (*)(void *, dtrace_id_t, void *))dtrace_nullop,
257 NULL,
258 NULL,
259 NULL,
260 (void (*)(void *, dtrace_id_t, void *))dtrace_nullop
261 };
262
263 static dtrace_id_t dtrace_probeid_begin; /* special BEGIN probe */
264 static dtrace_id_t dtrace_probeid_end; /* special END probe */
265 dtrace_id_t dtrace_probeid_error; /* special ERROR probe */
266
267 /*
268 * DTrace Helper Tracing Variables
269 */
270 uint32_t dtrace_helptrace_next = 0;
271 uint32_t dtrace_helptrace_nlocals;
272 char *dtrace_helptrace_buffer;
273 int dtrace_helptrace_bufsize = 512 * 1024;
274
275 #ifdef DEBUG
276 int dtrace_helptrace_enabled = 1;
277 #else
278 int dtrace_helptrace_enabled = 0;
279 #endif
280
281 /*
282 * DTrace Error Hashing
283 *
284 * On DEBUG kernels, DTrace will track the errors that has seen in a hash
285 * table. This is very useful for checking coverage of tests that are
286 * expected to induce DIF or DOF processing errors, and may be useful for
287 * debugging problems in the DIF code generator or in DOF generation . The
288 * error hash may be examined with the ::dtrace_errhash MDB dcmd.
289 */
290 #ifdef DEBUG
291 static dtrace_errhash_t dtrace_errhash[DTRACE_ERRHASHSZ];
292 static const char *dtrace_errlast;
293 static kthread_t *dtrace_errthread;
294 static kmutex_t dtrace_errlock;
295 #endif
296
297 /*
298 * DTrace Macros and Constants
299 *
300 * These are various macros that are useful in various spots in the
301 * implementation, along with a few random constants that have no meaning
302 * outside of the implementation. There is no real structure to this cpp
303 * mishmash -- but is there ever?
304 */
305 #define DTRACE_HASHSTR(hash, probe) \
306 dtrace_hash_str(*((char **)((uintptr_t)(probe) + (hash)->dth_stroffs)))
307
308 #define DTRACE_HASHNEXT(hash, probe) \
309 (dtrace_probe_t **)((uintptr_t)(probe) + (hash)->dth_nextoffs)
310
311 #define DTRACE_HASHPREV(hash, probe) \
312 (dtrace_probe_t **)((uintptr_t)(probe) + (hash)->dth_prevoffs)
313
314 #define DTRACE_HASHEQ(hash, lhs, rhs) \
315 (strcmp(*((char **)((uintptr_t)(lhs) + (hash)->dth_stroffs)), \
316 *((char **)((uintptr_t)(rhs) + (hash)->dth_stroffs))) == 0)
317
318 #define DTRACE_AGGHASHSIZE_SLEW 17
319
320 #define DTRACE_V4MAPPED_OFFSET (sizeof (uint32_t) * 3)
321
322 /*
323 * The key for a thread-local variable consists of the lower 61 bits of the
324 * t_did, plus the 3 bits of the highest active interrupt above LOCK_LEVEL.
325 * We add DIF_VARIABLE_MAX to t_did to assure that the thread key is never
326 * equal to a variable identifier. This is necessary (but not sufficient) to
327 * assure that global associative arrays never collide with thread-local
328 * variables. To guarantee that they cannot collide, we must also define the
329 * order for keying dynamic variables. That order is:
330 *
331 * [ key0 ] ... [ keyn ] [ variable-key ] [ tls-key ]
332 *
333 * Because the variable-key and the tls-key are in orthogonal spaces, there is
334 * no way for a global variable key signature to match a thread-local key
335 * signature.
336 */
337 #define DTRACE_TLS_THRKEY(where) { \
338 uint_t intr = 0; \
339 uint_t actv = CPU->cpu_intr_actv >> (LOCK_LEVEL + 1); \
340 for (; actv; actv >>= 1) \
341 intr++; \
342 ASSERT(intr < (1 << 3)); \
343 (where) = ((curthread->t_did + DIF_VARIABLE_MAX) & \
344 (((uint64_t)1 << 61) - 1)) | ((uint64_t)intr << 61); \
345 }
346
347 #define DT_BSWAP_8(x) ((x) & 0xff)
348 #define DT_BSWAP_16(x) ((DT_BSWAP_8(x) << 8) | DT_BSWAP_8((x) >> 8))
349 #define DT_BSWAP_32(x) ((DT_BSWAP_16(x) << 16) | DT_BSWAP_16((x) >> 16))
350 #define DT_BSWAP_64(x) ((DT_BSWAP_32(x) << 32) | DT_BSWAP_32((x) >> 32))
351
352 #define DT_MASK_LO 0x00000000FFFFFFFFULL
353
354 #define DTRACE_STORE(type, tomax, offset, what) \
355 *((type *)((uintptr_t)(tomax) + (uintptr_t)offset)) = (type)(what);
356
357 #ifndef __i386
358 #define DTRACE_ALIGNCHECK(addr, size, flags) \
359 if (addr & (size - 1)) { \
360 *flags |= CPU_DTRACE_BADALIGN; \
361 cpu_core[CPU->cpu_id].cpuc_dtrace_illval = addr; \
362 return (0); \
363 }
364 #else
365 #define DTRACE_ALIGNCHECK(addr, size, flags)
366 #endif
367
368 /*
369 * Test whether a range of memory starting at testaddr of size testsz falls
370 * within the range of memory described by addr, sz. We take care to avoid
371 * problems with overflow and underflow of the unsigned quantities, and
372 * disallow all negative sizes. Ranges of size 0 are allowed.
373 */
374 #define DTRACE_INRANGE(testaddr, testsz, baseaddr, basesz) \
375 ((testaddr) - (baseaddr) < (basesz) && \
376 (testaddr) + (testsz) - (baseaddr) <= (basesz) && \
377 (testaddr) + (testsz) >= (testaddr))
378
379 /*
380 * Test whether alloc_sz bytes will fit in the scratch region. We isolate
381 * alloc_sz on the righthand side of the comparison in order to avoid overflow
382 * or underflow in the comparison with it. This is simpler than the INRANGE
383 * check above, because we know that the dtms_scratch_ptr is valid in the
384 * range. Allocations of size zero are allowed.
385 */
386 #define DTRACE_INSCRATCH(mstate, alloc_sz) \
387 ((mstate)->dtms_scratch_base + (mstate)->dtms_scratch_size - \
388 (mstate)->dtms_scratch_ptr >= (alloc_sz))
389
390 #define DTRACE_LOADFUNC(bits) \
391 /*CSTYLED*/ \
392 uint##bits##_t \
393 dtrace_load##bits(uintptr_t addr) \
394 { \
395 size_t size = bits / NBBY; \
396 /*CSTYLED*/ \
397 uint##bits##_t rval; \
398 int i; \
399 volatile uint16_t *flags = (volatile uint16_t *) \
400 &cpu_core[CPU->cpu_id].cpuc_dtrace_flags; \
401 \
402 DTRACE_ALIGNCHECK(addr, size, flags); \
403 \
404 for (i = 0; i < dtrace_toxranges; i++) { \
405 if (addr >= dtrace_toxrange[i].dtt_limit) \
406 continue; \
407 \
408 if (addr + size <= dtrace_toxrange[i].dtt_base) \
409 continue; \
410 \
411 /* \
412 * This address falls within a toxic region; return 0. \
413 */ \
414 *flags |= CPU_DTRACE_BADADDR; \
415 cpu_core[CPU->cpu_id].cpuc_dtrace_illval = addr; \
416 return (0); \
417 } \
418 \
419 *flags |= CPU_DTRACE_NOFAULT; \
420 /*CSTYLED*/ \
421 rval = *((volatile uint##bits##_t *)addr); \
422 *flags &= ~CPU_DTRACE_NOFAULT; \
423 \
424 return (!(*flags & CPU_DTRACE_FAULT) ? rval : 0); \
425 }
426
427 #ifdef _LP64
428 #define dtrace_loadptr dtrace_load64
429 #else
430 #define dtrace_loadptr dtrace_load32
431 #endif
432
433 #define DTRACE_DYNHASH_FREE 0
434 #define DTRACE_DYNHASH_SINK 1
435 #define DTRACE_DYNHASH_VALID 2
436
437 #define DTRACE_MATCH_FAIL -1
438 #define DTRACE_MATCH_NEXT 0
439 #define DTRACE_MATCH_DONE 1
440 #define DTRACE_ANCHORED(probe) ((probe)->dtpr_func[0] != '\0')
441 #define DTRACE_STATE_ALIGN 64
442
443 #define DTRACE_FLAGS2FLT(flags) \
444 (((flags) & CPU_DTRACE_BADADDR) ? DTRACEFLT_BADADDR : \
445 ((flags) & CPU_DTRACE_ILLOP) ? DTRACEFLT_ILLOP : \
446 ((flags) & CPU_DTRACE_DIVZERO) ? DTRACEFLT_DIVZERO : \
447 ((flags) & CPU_DTRACE_KPRIV) ? DTRACEFLT_KPRIV : \
448 ((flags) & CPU_DTRACE_UPRIV) ? DTRACEFLT_UPRIV : \
449 ((flags) & CPU_DTRACE_TUPOFLOW) ? DTRACEFLT_TUPOFLOW : \
450 ((flags) & CPU_DTRACE_BADALIGN) ? DTRACEFLT_BADALIGN : \
451 ((flags) & CPU_DTRACE_NOSCRATCH) ? DTRACEFLT_NOSCRATCH : \
452 ((flags) & CPU_DTRACE_BADSTACK) ? DTRACEFLT_BADSTACK : \
453 DTRACEFLT_UNKNOWN)
454
455 #define DTRACEACT_ISSTRING(act) \
456 ((act)->dta_kind == DTRACEACT_DIFEXPR && \
457 (act)->dta_difo->dtdo_rtype.dtdt_kind == DIF_TYPE_STRING)
458
459 static size_t dtrace_strlen(const char *, size_t);
460 static dtrace_probe_t *dtrace_probe_lookup_id(dtrace_id_t id);
461 static void dtrace_enabling_provide(dtrace_provider_t *);
462 static int dtrace_enabling_match(dtrace_enabling_t *, int *);
463 static void dtrace_enabling_matchall(void);
464 static void dtrace_enabling_reap(void);
465 static dtrace_state_t *dtrace_anon_grab(void);
466 static uint64_t dtrace_helper(int, dtrace_mstate_t *,
467 dtrace_state_t *, uint64_t, uint64_t);
468 static dtrace_helpers_t *dtrace_helpers_create(proc_t *);
469 static void dtrace_buffer_drop(dtrace_buffer_t *);
470 static int dtrace_buffer_consumed(dtrace_buffer_t *, hrtime_t when);
471 static intptr_t dtrace_buffer_reserve(dtrace_buffer_t *, size_t, size_t,
472 dtrace_state_t *, dtrace_mstate_t *);
473 static int dtrace_state_option(dtrace_state_t *, dtrace_optid_t,
474 dtrace_optval_t);
475 static int dtrace_ecb_create_enable(dtrace_probe_t *, void *);
476 static void dtrace_helper_provider_destroy(dtrace_helper_provider_t *);
477
478 /*
479 * DTrace Probe Context Functions
480 *
481 * These functions are called from probe context. Because probe context is
482 * any context in which C may be called, arbitrarily locks may be held,
483 * interrupts may be disabled, we may be in arbitrary dispatched state, etc.
484 * As a result, functions called from probe context may only call other DTrace
485 * support functions -- they may not interact at all with the system at large.
486 * (Note that the ASSERT macro is made probe-context safe by redefining it in
487 * terms of dtrace_assfail(), a probe-context safe function.) If arbitrary
488 * loads are to be performed from probe context, they _must_ be in terms of
489 * the safe dtrace_load*() variants.
490 *
491 * Some functions in this block are not actually called from probe context;
492 * for these functions, there will be a comment above the function reading
493 * "Note: not called from probe context."
494 */
495 void
496 dtrace_panic(const char *format, ...)
497 {
498 va_list alist;
499
500 va_start(alist, format);
501 dtrace_vpanic(format, alist);
502 va_end(alist);
503 }
504
505 int
506 dtrace_assfail(const char *a, const char *f, int l)
507 {
508 dtrace_panic("assertion failed: %s, file: %s, line: %d", a, f, l);
509
510 /*
511 * We just need something here that even the most clever compiler
512 * cannot optimize away.
513 */
514 return (a[(uintptr_t)f]);
515 }
516
517 /*
518 * Atomically increment a specified error counter from probe context.
519 */
520 static void
521 dtrace_error(uint32_t *counter)
522 {
523 /*
524 * Most counters stored to in probe context are per-CPU counters.
525 * However, there are some error conditions that are sufficiently
526 * arcane that they don't merit per-CPU storage. If these counters
527 * are incremented concurrently on different CPUs, scalability will be
528 * adversely affected -- but we don't expect them to be white-hot in a
529 * correctly constructed enabling...
530 */
531 uint32_t oval, nval;
532
533 do {
534 oval = *counter;
535
536 if ((nval = oval + 1) == 0) {
537 /*
538 * If the counter would wrap, set it to 1 -- assuring
539 * that the counter is never zero when we have seen
540 * errors. (The counter must be 32-bits because we
541 * aren't guaranteed a 64-bit compare&swap operation.)
542 * To save this code both the infamy of being fingered
543 * by a priggish news story and the indignity of being
544 * the target of a neo-puritan witch trial, we're
545 * carefully avoiding any colorful description of the
546 * likelihood of this condition -- but suffice it to
547 * say that it is only slightly more likely than the
548 * overflow of predicate cache IDs, as discussed in
549 * dtrace_predicate_create().
550 */
551 nval = 1;
552 }
553 } while (dtrace_cas32(counter, oval, nval) != oval);
554 }
555
556 /*
557 * Use the DTRACE_LOADFUNC macro to define functions for each of loading a
558 * uint8_t, a uint16_t, a uint32_t and a uint64_t.
559 */
560 DTRACE_LOADFUNC(8)
561 DTRACE_LOADFUNC(16)
562 DTRACE_LOADFUNC(32)
563 DTRACE_LOADFUNC(64)
564
565 static int
566 dtrace_inscratch(uintptr_t dest, size_t size, dtrace_mstate_t *mstate)
567 {
568 if (dest < mstate->dtms_scratch_base)
569 return (0);
570
571 if (dest + size < dest)
572 return (0);
573
574 if (dest + size > mstate->dtms_scratch_ptr)
575 return (0);
576
577 return (1);
578 }
579
580 static int
581 dtrace_canstore_statvar(uint64_t addr, size_t sz,
582 dtrace_statvar_t **svars, int nsvars)
583 {
584 int i;
585
586 for (i = 0; i < nsvars; i++) {
587 dtrace_statvar_t *svar = svars[i];
588
589 if (svar == NULL || svar->dtsv_size == 0)
590 continue;
591
592 if (DTRACE_INRANGE(addr, sz, svar->dtsv_data, svar->dtsv_size))
593 return (1);
594 }
595
596 return (0);
597 }
598
599 /*
600 * Check to see if the address is within a memory region to which a store may
601 * be issued. This includes the DTrace scratch areas, and any DTrace variable
602 * region. The caller of dtrace_canstore() is responsible for performing any
603 * alignment checks that are needed before stores are actually executed.
604 */
605 static int
606 dtrace_canstore(uint64_t addr, size_t sz, dtrace_mstate_t *mstate,
607 dtrace_vstate_t *vstate)
608 {
609 /*
610 * First, check to see if the address is in scratch space...
611 */
612 if (DTRACE_INRANGE(addr, sz, mstate->dtms_scratch_base,
613 mstate->dtms_scratch_size))
614 return (1);
615
616 /*
617 * Now check to see if it's a dynamic variable. This check will pick
618 * up both thread-local variables and any global dynamically-allocated
619 * variables.
620 */
621 if (DTRACE_INRANGE(addr, sz, (uintptr_t)vstate->dtvs_dynvars.dtds_base,
622 vstate->dtvs_dynvars.dtds_size)) {
623 dtrace_dstate_t *dstate = &vstate->dtvs_dynvars;
624 uintptr_t base = (uintptr_t)dstate->dtds_base +
625 (dstate->dtds_hashsize * sizeof (dtrace_dynhash_t));
626 uintptr_t chunkoffs;
627
628 /*
629 * Before we assume that we can store here, we need to make
630 * sure that it isn't in our metadata -- storing to our
631 * dynamic variable metadata would corrupt our state. For
632 * the range to not include any dynamic variable metadata,
633 * it must:
634 *
635 * (1) Start above the hash table that is at the base of
636 * the dynamic variable space
637 *
638 * (2) Have a starting chunk offset that is beyond the
639 * dtrace_dynvar_t that is at the base of every chunk
640 *
641 * (3) Not span a chunk boundary
642 *
643 */
644 if (addr < base)
645 return (0);
646
647 chunkoffs = (addr - base) % dstate->dtds_chunksize;
648
649 if (chunkoffs < sizeof (dtrace_dynvar_t))
650 return (0);
651
652 if (chunkoffs + sz > dstate->dtds_chunksize)
653 return (0);
654
655 return (1);
656 }
657
658 /*
659 * Finally, check the static local and global variables. These checks
660 * take the longest, so we perform them last.
661 */
662 if (dtrace_canstore_statvar(addr, sz,
663 vstate->dtvs_locals, vstate->dtvs_nlocals))
664 return (1);
665
666 if (dtrace_canstore_statvar(addr, sz,
667 vstate->dtvs_globals, vstate->dtvs_nglobals))
668 return (1);
669
670 return (0);
671 }
672
673
674 /*
675 * Convenience routine to check to see if the address is within a memory
676 * region in which a load may be issued given the user's privilege level;
677 * if not, it sets the appropriate error flags and loads 'addr' into the
678 * illegal value slot.
679 *
680 * DTrace subroutines (DIF_SUBR_*) should use this helper to implement
681 * appropriate memory access protection.
682 */
683 static int
684 dtrace_canload(uint64_t addr, size_t sz, dtrace_mstate_t *mstate,
685 dtrace_vstate_t *vstate)
686 {
687 volatile uintptr_t *illval = &cpu_core[CPU->cpu_id].cpuc_dtrace_illval;
688
689 /*
690 * If we hold the privilege to read from kernel memory, then
691 * everything is readable.
692 */
693 if ((mstate->dtms_access & DTRACE_ACCESS_KERNEL) != 0)
694 return (1);
695
696 /*
697 * You can obviously read that which you can store.
698 */
699 if (dtrace_canstore(addr, sz, mstate, vstate))
700 return (1);
701
702 /*
703 * We're allowed to read from our own string table.
704 */
705 if (DTRACE_INRANGE(addr, sz, (uintptr_t)mstate->dtms_difo->dtdo_strtab,
706 mstate->dtms_difo->dtdo_strlen))
707 return (1);
708
709 DTRACE_CPUFLAG_SET(CPU_DTRACE_KPRIV);
710 *illval = addr;
711 return (0);
712 }
713
714 /*
715 * Convenience routine to check to see if a given string is within a memory
716 * region in which a load may be issued given the user's privilege level;
717 * this exists so that we don't need to issue unnecessary dtrace_strlen()
718 * calls in the event that the user has all privileges.
719 */
720 static int
721 dtrace_strcanload(uint64_t addr, size_t sz, dtrace_mstate_t *mstate,
722 dtrace_vstate_t *vstate)
723 {
724 size_t strsz;
725
726 /*
727 * If we hold the privilege to read from kernel memory, then
728 * everything is readable.
729 */
730 if ((mstate->dtms_access & DTRACE_ACCESS_KERNEL) != 0)
731 return (1);
732
733 strsz = 1 + dtrace_strlen((char *)(uintptr_t)addr, sz);
734 if (dtrace_canload(addr, strsz, mstate, vstate))
735 return (1);
736
737 return (0);
738 }
739
740 /*
741 * Convenience routine to check to see if a given variable is within a memory
742 * region in which a load may be issued given the user's privilege level.
743 */
744 static int
745 dtrace_vcanload(void *src, dtrace_diftype_t *type, dtrace_mstate_t *mstate,
746 dtrace_vstate_t *vstate)
747 {
748 size_t sz;
749 ASSERT(type->dtdt_flags & DIF_TF_BYREF);
750
751 /*
752 * If we hold the privilege to read from kernel memory, then
753 * everything is readable.
754 */
755 if ((mstate->dtms_access & DTRACE_ACCESS_KERNEL) != 0)
756 return (1);
757
758 if (type->dtdt_kind == DIF_TYPE_STRING)
759 sz = dtrace_strlen(src,
760 vstate->dtvs_state->dts_options[DTRACEOPT_STRSIZE]) + 1;
761 else
762 sz = type->dtdt_size;
763
764 return (dtrace_canload((uintptr_t)src, sz, mstate, vstate));
765 }
766
767 /*
768 * Compare two strings using safe loads.
769 */
770 static int
771 dtrace_strncmp(char *s1, char *s2, size_t limit)
772 {
773 uint8_t c1, c2;
774 volatile uint16_t *flags;
775
776 if (s1 == s2 || limit == 0)
777 return (0);
778
779 flags = (volatile uint16_t *)&cpu_core[CPU->cpu_id].cpuc_dtrace_flags;
780
781 do {
782 if (s1 == NULL) {
783 c1 = '\0';
784 } else {
785 c1 = dtrace_load8((uintptr_t)s1++);
786 }
787
788 if (s2 == NULL) {
789 c2 = '\0';
790 } else {
791 c2 = dtrace_load8((uintptr_t)s2++);
792 }
793
794 if (c1 != c2)
795 return (c1 - c2);
796 } while (--limit && c1 != '\0' && !(*flags & CPU_DTRACE_FAULT));
797
798 return (0);
799 }
800
801 /*
802 * Compute strlen(s) for a string using safe memory accesses. The additional
803 * len parameter is used to specify a maximum length to ensure completion.
804 */
805 static size_t
806 dtrace_strlen(const char *s, size_t lim)
807 {
808 uint_t len;
809
810 for (len = 0; len != lim; len++) {
811 if (dtrace_load8((uintptr_t)s++) == '\0')
812 break;
813 }
814
815 return (len);
816 }
817
818 /*
819 * Check if an address falls within a toxic region.
820 */
821 static int
822 dtrace_istoxic(uintptr_t kaddr, size_t size)
823 {
824 uintptr_t taddr, tsize;
825 int i;
826
827 for (i = 0; i < dtrace_toxranges; i++) {
828 taddr = dtrace_toxrange[i].dtt_base;
829 tsize = dtrace_toxrange[i].dtt_limit - taddr;
830
831 if (kaddr - taddr < tsize) {
832 DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR);
833 cpu_core[CPU->cpu_id].cpuc_dtrace_illval = kaddr;
834 return (1);
835 }
836
837 if (taddr - kaddr < size) {
838 DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR);
839 cpu_core[CPU->cpu_id].cpuc_dtrace_illval = taddr;
840 return (1);
841 }
842 }
843
844 return (0);
845 }
846
847 /*
848 * Copy src to dst using safe memory accesses. The src is assumed to be unsafe
849 * memory specified by the DIF program. The dst is assumed to be safe memory
850 * that we can store to directly because it is managed by DTrace. As with
851 * standard bcopy, overlapping copies are handled properly.
852 */
853 static void
854 dtrace_bcopy(const void *src, void *dst, size_t len)
855 {
856 if (len != 0) {
857 uint8_t *s1 = dst;
858 const uint8_t *s2 = src;
859
860 if (s1 <= s2) {
861 do {
862 *s1++ = dtrace_load8((uintptr_t)s2++);
863 } while (--len != 0);
864 } else {
865 s2 += len;
866 s1 += len;
867
868 do {
869 *--s1 = dtrace_load8((uintptr_t)--s2);
870 } while (--len != 0);
871 }
872 }
873 }
874
875 /*
876 * Copy src to dst using safe memory accesses, up to either the specified
877 * length, or the point that a nul byte is encountered. The src is assumed to
878 * be unsafe memory specified by the DIF program. The dst is assumed to be
879 * safe memory that we can store to directly because it is managed by DTrace.
880 * Unlike dtrace_bcopy(), overlapping regions are not handled.
881 */
882 static void
883 dtrace_strcpy(const void *src, void *dst, size_t len)
884 {
885 if (len != 0) {
886 uint8_t *s1 = dst, c;
887 const uint8_t *s2 = src;
888
889 do {
890 *s1++ = c = dtrace_load8((uintptr_t)s2++);
891 } while (--len != 0 && c != '\0');
892 }
893 }
894
895 /*
896 * Copy src to dst, deriving the size and type from the specified (BYREF)
897 * variable type. The src is assumed to be unsafe memory specified by the DIF
898 * program. The dst is assumed to be DTrace variable memory that is of the
899 * specified type; we assume that we can store to directly.
900 */
901 static void
902 dtrace_vcopy(void *src, void *dst, dtrace_diftype_t *type)
903 {
904 ASSERT(type->dtdt_flags & DIF_TF_BYREF);
905
906 if (type->dtdt_kind == DIF_TYPE_STRING) {
907 dtrace_strcpy(src, dst, type->dtdt_size);
908 } else {
909 dtrace_bcopy(src, dst, type->dtdt_size);
910 }
911 }
912
913 /*
914 * Compare s1 to s2 using safe memory accesses. The s1 data is assumed to be
915 * unsafe memory specified by the DIF program. The s2 data is assumed to be
916 * safe memory that we can access directly because it is managed by DTrace.
917 */
918 static int
919 dtrace_bcmp(const void *s1, const void *s2, size_t len)
920 {
921 volatile uint16_t *flags;
922
923 flags = (volatile uint16_t *)&cpu_core[CPU->cpu_id].cpuc_dtrace_flags;
924
925 if (s1 == s2)
926 return (0);
927
928 if (s1 == NULL || s2 == NULL)
929 return (1);
930
931 if (s1 != s2 && len != 0) {
932 const uint8_t *ps1 = s1;
933 const uint8_t *ps2 = s2;
934
935 do {
936 if (dtrace_load8((uintptr_t)ps1++) != *ps2++)
937 return (1);
938 } while (--len != 0 && !(*flags & CPU_DTRACE_FAULT));
939 }
940 return (0);
941 }
942
943 /*
944 * Zero the specified region using a simple byte-by-byte loop. Note that this
945 * is for safe DTrace-managed memory only.
946 */
947 static void
948 dtrace_bzero(void *dst, size_t len)
949 {
950 uchar_t *cp;
951
952 for (cp = dst; len != 0; len--)
953 *cp++ = 0;
954 }
955
956 static void
957 dtrace_add_128(uint64_t *addend1, uint64_t *addend2, uint64_t *sum)
958 {
959 uint64_t result[2];
960
961 result[0] = addend1[0] + addend2[0];
962 result[1] = addend1[1] + addend2[1] +
963 (result[0] < addend1[0] || result[0] < addend2[0] ? 1 : 0);
964
965 sum[0] = result[0];
966 sum[1] = result[1];
967 }
968
969 /*
970 * Shift the 128-bit value in a by b. If b is positive, shift left.
971 * If b is negative, shift right.
972 */
973 static void
974 dtrace_shift_128(uint64_t *a, int b)
975 {
976 uint64_t mask;
977
978 if (b == 0)
979 return;
980
981 if (b < 0) {
982 b = -b;
983 if (b >= 64) {
984 a[0] = a[1] >> (b - 64);
985 a[1] = 0;
986 } else {
987 a[0] >>= b;
988 mask = 1LL << (64 - b);
989 mask -= 1;
990 a[0] |= ((a[1] & mask) << (64 - b));
991 a[1] >>= b;
992 }
993 } else {
994 if (b >= 64) {
995 a[1] = a[0] << (b - 64);
996 a[0] = 0;
997 } else {
998 a[1] <<= b;
999 mask = a[0] >> (64 - b);
1000 a[1] |= mask;
1001 a[0] <<= b;
1002 }
1003 }
1004 }
1005
1006 /*
1007 * The basic idea is to break the 2 64-bit values into 4 32-bit values,
1008 * use native multiplication on those, and then re-combine into the
1009 * resulting 128-bit value.
1010 *
1011 * (hi1 << 32 + lo1) * (hi2 << 32 + lo2) =
1012 * hi1 * hi2 << 64 +
1013 * hi1 * lo2 << 32 +
1014 * hi2 * lo1 << 32 +
1015 * lo1 * lo2
1016 */
1017 static void
1018 dtrace_multiply_128(uint64_t factor1, uint64_t factor2, uint64_t *product)
1019 {
1020 uint64_t hi1, hi2, lo1, lo2;
1021 uint64_t tmp[2];
1022
1023 hi1 = factor1 >> 32;
1024 hi2 = factor2 >> 32;
1025
1026 lo1 = factor1 & DT_MASK_LO;
1027 lo2 = factor2 & DT_MASK_LO;
1028
1029 product[0] = lo1 * lo2;
1030 product[1] = hi1 * hi2;
1031
1032 tmp[0] = hi1 * lo2;
1033 tmp[1] = 0;
1034 dtrace_shift_128(tmp, 32);
1035 dtrace_add_128(product, tmp, product);
1036
1037 tmp[0] = hi2 * lo1;
1038 tmp[1] = 0;
1039 dtrace_shift_128(tmp, 32);
1040 dtrace_add_128(product, tmp, product);
1041 }
1042
1043 /*
1044 * This privilege check should be used by actions and subroutines to
1045 * verify that the user credentials of the process that enabled the
1046 * invoking ECB match the target credentials
1047 */
1048 static int
1049 dtrace_priv_proc_common_user(dtrace_state_t *state)
1050 {
1051 cred_t *cr, *s_cr = state->dts_cred.dcr_cred;
1052
1053 /*
1054 * We should always have a non-NULL state cred here, since if cred
1055 * is null (anonymous tracing), we fast-path bypass this routine.
1056 */
1057 ASSERT(s_cr != NULL);
1058
1059 if ((cr = CRED()) != NULL &&
1060 s_cr->cr_uid == cr->cr_uid &&
1061 s_cr->cr_uid == cr->cr_ruid &&
1062 s_cr->cr_uid == cr->cr_suid &&
1063 s_cr->cr_gid == cr->cr_gid &&
1064 s_cr->cr_gid == cr->cr_rgid &&
1065 s_cr->cr_gid == cr->cr_sgid)
1066 return (1);
1067
1068 return (0);
1069 }
1070
1071 /*
1072 * This privilege check should be used by actions and subroutines to
1073 * verify that the zone of the process that enabled the invoking ECB
1074 * matches the target credentials
1075 */
1076 static int
1077 dtrace_priv_proc_common_zone(dtrace_state_t *state)
1078 {
1079 cred_t *cr, *s_cr = state->dts_cred.dcr_cred;
1080
1081 /*
1082 * We should always have a non-NULL state cred here, since if cred
1083 * is null (anonymous tracing), we fast-path bypass this routine.
1084 */
1085 ASSERT(s_cr != NULL);
1086
1087 if ((cr = CRED()) != NULL &&
1088 s_cr->cr_zone == cr->cr_zone)
1089 return (1);
1090
1091 return (0);
1092 }
1093
1094 /*
1095 * This privilege check should be used by actions and subroutines to
1096 * verify that the process has not setuid or changed credentials.
1097 */
1098 static int
1099 dtrace_priv_proc_common_nocd()
1100 {
1101 proc_t *proc;
1102
1103 if ((proc = ttoproc(curthread)) != NULL &&
1104 !(proc->p_flag & SNOCD))
1105 return (1);
1106
1107 return (0);
1108 }
1109
1110 static int
1111 dtrace_priv_proc_destructive(dtrace_state_t *state, dtrace_mstate_t *mstate)
1112 {
1113 int action = state->dts_cred.dcr_action;
1114
1115 if (!(mstate->dtms_access & DTRACE_ACCESS_PROC))
1116 goto bad;
1117
1118 if (((action & DTRACE_CRA_PROC_DESTRUCTIVE_ALLZONE) == 0) &&
1119 dtrace_priv_proc_common_zone(state) == 0)
1120 goto bad;
1121
1122 if (((action & DTRACE_CRA_PROC_DESTRUCTIVE_ALLUSER) == 0) &&
1123 dtrace_priv_proc_common_user(state) == 0)
1124 goto bad;
1125
1126 if (((action & DTRACE_CRA_PROC_DESTRUCTIVE_CREDCHG) == 0) &&
1127 dtrace_priv_proc_common_nocd() == 0)
1128 goto bad;
1129
1130 return (1);
1131
1132 bad:
1133 cpu_core[CPU->cpu_id].cpuc_dtrace_flags |= CPU_DTRACE_UPRIV;
1134
1135 return (0);
1136 }
1137
1138 static int
1139 dtrace_priv_proc_control(dtrace_state_t *state, dtrace_mstate_t *mstate)
1140 {
1141 if (mstate->dtms_access & DTRACE_ACCESS_PROC) {
1142 if (state->dts_cred.dcr_action & DTRACE_CRA_PROC_CONTROL)
1143 return (1);
1144
1145 if (dtrace_priv_proc_common_zone(state) &&
1146 dtrace_priv_proc_common_user(state) &&
1147 dtrace_priv_proc_common_nocd())
1148 return (1);
1149 }
1150
1151 cpu_core[CPU->cpu_id].cpuc_dtrace_flags |= CPU_DTRACE_UPRIV;
1152
1153 return (0);
1154 }
1155
1156 static int
1157 dtrace_priv_proc(dtrace_state_t *state, dtrace_mstate_t *mstate)
1158 {
1159 if ((mstate->dtms_access & DTRACE_ACCESS_PROC) &&
1160 (state->dts_cred.dcr_action & DTRACE_CRA_PROC))
1161 return (1);
1162
1163 cpu_core[CPU->cpu_id].cpuc_dtrace_flags |= CPU_DTRACE_UPRIV;
1164
1165 return (0);
1166 }
1167
1168 static int
1169 dtrace_priv_kernel(dtrace_state_t *state)
1170 {
1171 if (state->dts_cred.dcr_action & DTRACE_CRA_KERNEL)
1172 return (1);
1173
1174 cpu_core[CPU->cpu_id].cpuc_dtrace_flags |= CPU_DTRACE_KPRIV;
1175
1176 return (0);
1177 }
1178
1179 static int
1180 dtrace_priv_kernel_destructive(dtrace_state_t *state)
1181 {
1182 if (state->dts_cred.dcr_action & DTRACE_CRA_KERNEL_DESTRUCTIVE)
1183 return (1);
1184
1185 cpu_core[CPU->cpu_id].cpuc_dtrace_flags |= CPU_DTRACE_KPRIV;
1186
1187 return (0);
1188 }
1189
1190 /*
1191 * Determine if the dte_cond of the specified ECB allows for processing of
1192 * the current probe to continue. Note that this routine may allow continued
1193 * processing, but with access(es) stripped from the mstate's dtms_access
1194 * field.
1195 */
1196 static int
1197 dtrace_priv_probe(dtrace_state_t *state, dtrace_mstate_t *mstate,
1198 dtrace_ecb_t *ecb)
1199 {
1200 dtrace_probe_t *probe = ecb->dte_probe;
1201 dtrace_provider_t *prov = probe->dtpr_provider;
1202 dtrace_pops_t *pops = &prov->dtpv_pops;
1203 int mode = DTRACE_MODE_NOPRIV_DROP;
1204
1205 ASSERT(ecb->dte_cond);
1206
1207 if (pops->dtps_mode != NULL) {
1208 mode = pops->dtps_mode(prov->dtpv_arg,
1209 probe->dtpr_id, probe->dtpr_arg);
1210
1211 ASSERT((mode & DTRACE_MODE_USER) ||
1212 (mode & DTRACE_MODE_KERNEL));
1213 ASSERT((mode & DTRACE_MODE_NOPRIV_RESTRICT) ||
1214 (mode & DTRACE_MODE_NOPRIV_DROP));
1215 }
1216
1217 /*
1218 * If the dte_cond bits indicate that this consumer is only allowed to
1219 * see user-mode firings of this probe, call the provider's dtps_mode()
1220 * entry point to check that the probe was fired while in a user
1221 * context. If that's not the case, use the policy specified by the
1222 * provider to determine if we drop the probe or merely restrict
1223 * operation.
1224 */
1225 if (ecb->dte_cond & DTRACE_COND_USERMODE) {
1226 ASSERT(mode != DTRACE_MODE_NOPRIV_DROP);
1227
1228 if (!(mode & DTRACE_MODE_USER)) {
1229 if (mode & DTRACE_MODE_NOPRIV_DROP)
1230 return (0);
1231
1232 mstate->dtms_access &= ~DTRACE_ACCESS_ARGS;
1233 }
1234 }
1235
1236 /*
1237 * This is more subtle than it looks. We have to be absolutely certain
1238 * that CRED() isn't going to change out from under us so it's only
1239 * legit to examine that structure if we're in constrained situations.
1240 * Currently, the only times we'll this check is if a non-super-user
1241 * has enabled the profile or syscall providers -- providers that
1242 * allow visibility of all processes. For the profile case, the check
1243 * above will ensure that we're examining a user context.
1244 */
1245 if (ecb->dte_cond & DTRACE_COND_OWNER) {
1246 cred_t *cr;
1247 cred_t *s_cr = state->dts_cred.dcr_cred;
1248 proc_t *proc;
1249
1250 ASSERT(s_cr != NULL);
1251
1252 if ((cr = CRED()) == NULL ||
1253 s_cr->cr_uid != cr->cr_uid ||
1254 s_cr->cr_uid != cr->cr_ruid ||
1255 s_cr->cr_uid != cr->cr_suid ||
1256 s_cr->cr_gid != cr->cr_gid ||
1257 s_cr->cr_gid != cr->cr_rgid ||
1258 s_cr->cr_gid != cr->cr_sgid ||
1259 (proc = ttoproc(curthread)) == NULL ||
1260 (proc->p_flag & SNOCD)) {
1261 if (mode & DTRACE_MODE_NOPRIV_DROP)
1262 return (0);
1263
1264 mstate->dtms_access &= ~DTRACE_ACCESS_PROC;
1265 }
1266 }
1267
1268 /*
1269 * If our dte_cond is set to DTRACE_COND_ZONEOWNER and we are not
1270 * in our zone, check to see if our mode policy is to restrict rather
1271 * than to drop; if to restrict, strip away both DTRACE_ACCESS_PROC
1272 * and DTRACE_ACCESS_ARGS
1273 */
1274 if (ecb->dte_cond & DTRACE_COND_ZONEOWNER) {
1275 cred_t *cr;
1276 cred_t *s_cr = state->dts_cred.dcr_cred;
1277
1278 ASSERT(s_cr != NULL);
1279
1280 if ((cr = CRED()) == NULL ||
1281 s_cr->cr_zone->zone_id != cr->cr_zone->zone_id) {
1282 if (mode & DTRACE_MODE_NOPRIV_DROP)
1283 return (0);
1284
1285 mstate->dtms_access &=
1286 ~(DTRACE_ACCESS_PROC | DTRACE_ACCESS_ARGS);
1287 }
1288 }
1289
1290 return (1);
1291 }
1292
1293 /*
1294 * Note: not called from probe context. This function is called
1295 * asynchronously (and at a regular interval) from outside of probe context to
1296 * clean the dirty dynamic variable lists on all CPUs. Dynamic variable
1297 * cleaning is explained in detail in <sys/dtrace_impl.h>.
1298 */
1299 void
1300 dtrace_dynvar_clean(dtrace_dstate_t *dstate)
1301 {
1302 dtrace_dynvar_t *dirty;
1303 dtrace_dstate_percpu_t *dcpu;
1304 dtrace_dynvar_t **rinsep;
1305 int i, j, work = 0;
1306
1307 for (i = 0; i < NCPU; i++) {
1308 dcpu = &dstate->dtds_percpu[i];
1309 rinsep = &dcpu->dtdsc_rinsing;
1310
1311 /*
1312 * If the dirty list is NULL, there is no dirty work to do.
1313 */
1314 if (dcpu->dtdsc_dirty == NULL)
1315 continue;
1316
1317 if (dcpu->dtdsc_rinsing != NULL) {
1318 /*
1319 * If the rinsing list is non-NULL, then it is because
1320 * this CPU was selected to accept another CPU's
1321 * dirty list -- and since that time, dirty buffers
1322 * have accumulated. This is a highly unlikely
1323 * condition, but we choose to ignore the dirty
1324 * buffers -- they'll be picked up a future cleanse.
1325 */
1326 continue;
1327 }
1328
1329 if (dcpu->dtdsc_clean != NULL) {
1330 /*
1331 * If the clean list is non-NULL, then we're in a
1332 * situation where a CPU has done deallocations (we
1333 * have a non-NULL dirty list) but no allocations (we
1334 * also have a non-NULL clean list). We can't simply
1335 * move the dirty list into the clean list on this
1336 * CPU, yet we also don't want to allow this condition
1337 * to persist, lest a short clean list prevent a
1338 * massive dirty list from being cleaned (which in
1339 * turn could lead to otherwise avoidable dynamic
1340 * drops). To deal with this, we look for some CPU
1341 * with a NULL clean list, NULL dirty list, and NULL
1342 * rinsing list -- and then we borrow this CPU to
1343 * rinse our dirty list.
1344 */
1345 for (j = 0; j < NCPU; j++) {
1346 dtrace_dstate_percpu_t *rinser;
1347
1348 rinser = &dstate->dtds_percpu[j];
1349
1350 if (rinser->dtdsc_rinsing != NULL)
1351 continue;
1352
1353 if (rinser->dtdsc_dirty != NULL)
1354 continue;
1355
1356 if (rinser->dtdsc_clean != NULL)
1357 continue;
1358
1359 rinsep = &rinser->dtdsc_rinsing;
1360 break;
1361 }
1362
1363 if (j == NCPU) {
1364 /*
1365 * We were unable to find another CPU that
1366 * could accept this dirty list -- we are
1367 * therefore unable to clean it now.
1368 */
1369 dtrace_dynvar_failclean++;
1370 continue;
1371 }
1372 }
1373
1374 work = 1;
1375
1376 /*
1377 * Atomically move the dirty list aside.
1378 */
1379 do {
1380 dirty = dcpu->dtdsc_dirty;
1381
1382 /*
1383 * Before we zap the dirty list, set the rinsing list.
1384 * (This allows for a potential assertion in
1385 * dtrace_dynvar(): if a free dynamic variable appears
1386 * on a hash chain, either the dirty list or the
1387 * rinsing list for some CPU must be non-NULL.)
1388 */
1389 *rinsep = dirty;
1390 dtrace_membar_producer();
1391 } while (dtrace_casptr(&dcpu->dtdsc_dirty,
1392 dirty, NULL) != dirty);
1393 }
1394
1395 if (!work) {
1396 /*
1397 * We have no work to do; we can simply return.
1398 */
1399 return;
1400 }
1401
1402 dtrace_sync();
1403
1404 for (i = 0; i < NCPU; i++) {
1405 dcpu = &dstate->dtds_percpu[i];
1406
1407 if (dcpu->dtdsc_rinsing == NULL)
1408 continue;
1409
1410 /*
1411 * We are now guaranteed that no hash chain contains a pointer
1412 * into this dirty list; we can make it clean.
1413 */
1414 ASSERT(dcpu->dtdsc_clean == NULL);
1415 dcpu->dtdsc_clean = dcpu->dtdsc_rinsing;
1416 dcpu->dtdsc_rinsing = NULL;
1417 }
1418
1419 /*
1420 * Before we actually set the state to be DTRACE_DSTATE_CLEAN, make
1421 * sure that all CPUs have seen all of the dtdsc_clean pointers.
1422 * This prevents a race whereby a CPU incorrectly decides that
1423 * the state should be something other than DTRACE_DSTATE_CLEAN
1424 * after dtrace_dynvar_clean() has completed.
1425 */
1426 dtrace_sync();
1427
1428 dstate->dtds_state = DTRACE_DSTATE_CLEAN;
1429 }
1430
1431 /*
1432 * Depending on the value of the op parameter, this function looks-up,
1433 * allocates or deallocates an arbitrarily-keyed dynamic variable. If an
1434 * allocation is requested, this function will return a pointer to a
1435 * dtrace_dynvar_t corresponding to the allocated variable -- or NULL if no
1436 * variable can be allocated. If NULL is returned, the appropriate counter
1437 * will be incremented.
1438 */
1439 dtrace_dynvar_t *
1440 dtrace_dynvar(dtrace_dstate_t *dstate, uint_t nkeys,
1441 dtrace_key_t *key, size_t dsize, dtrace_dynvar_op_t op,
1442 dtrace_mstate_t *mstate, dtrace_vstate_t *vstate)
1443 {
1444 uint64_t hashval = DTRACE_DYNHASH_VALID;
1445 dtrace_dynhash_t *hash = dstate->dtds_hash;
1446 dtrace_dynvar_t *free, *new_free, *next, *dvar, *start, *prev = NULL;
1447 processorid_t me = CPU->cpu_id, cpu = me;
1448 dtrace_dstate_percpu_t *dcpu = &dstate->dtds_percpu[me];
1449 size_t bucket, ksize;
1450 size_t chunksize = dstate->dtds_chunksize;
1451 uintptr_t kdata, lock, nstate;
1452 uint_t i;
1453
1454 ASSERT(nkeys != 0);
1455
1456 /*
1457 * Hash the key. As with aggregations, we use Jenkins' "One-at-a-time"
1458 * algorithm. For the by-value portions, we perform the algorithm in
1459 * 16-bit chunks (as opposed to 8-bit chunks). This speeds things up a
1460 * bit, and seems to have only a minute effect on distribution. For
1461 * the by-reference data, we perform "One-at-a-time" iterating (safely)
1462 * over each referenced byte. It's painful to do this, but it's much
1463 * better than pathological hash distribution. The efficacy of the
1464 * hashing algorithm (and a comparison with other algorithms) may be
1465 * found by running the ::dtrace_dynstat MDB dcmd.
1466 */
1467 for (i = 0; i < nkeys; i++) {
1468 if (key[i].dttk_size == 0) {
1469 uint64_t val = key[i].dttk_value;
1470
1471 hashval += (val >> 48) & 0xffff;
1472 hashval += (hashval << 10);
1473 hashval ^= (hashval >> 6);
1474
1475 hashval += (val >> 32) & 0xffff;
1476 hashval += (hashval << 10);
1477 hashval ^= (hashval >> 6);
1478
1479 hashval += (val >> 16) & 0xffff;
1480 hashval += (hashval << 10);
1481 hashval ^= (hashval >> 6);
1482
1483 hashval += val & 0xffff;
1484 hashval += (hashval << 10);
1485 hashval ^= (hashval >> 6);
1486 } else {
1487 /*
1488 * This is incredibly painful, but it beats the hell
1489 * out of the alternative.
1490 */
1491 uint64_t j, size = key[i].dttk_size;
1492 uintptr_t base = (uintptr_t)key[i].dttk_value;
1493
1494 if (!dtrace_canload(base, size, mstate, vstate))
1495 break;
1496
1497 for (j = 0; j < size; j++) {
1498 hashval += dtrace_load8(base + j);
1499 hashval += (hashval << 10);
1500 hashval ^= (hashval >> 6);
1501 }
1502 }
1503 }
1504
1505 if (DTRACE_CPUFLAG_ISSET(CPU_DTRACE_FAULT))
1506 return (NULL);
1507
1508 hashval += (hashval << 3);
1509 hashval ^= (hashval >> 11);
1510 hashval += (hashval << 15);
1511
1512 /*
1513 * There is a remote chance (ideally, 1 in 2^31) that our hashval
1514 * comes out to be one of our two sentinel hash values. If this
1515 * actually happens, we set the hashval to be a value known to be a
1516 * non-sentinel value.
1517 */
1518 if (hashval == DTRACE_DYNHASH_FREE || hashval == DTRACE_DYNHASH_SINK)
1519 hashval = DTRACE_DYNHASH_VALID;
1520
1521 /*
1522 * Yes, it's painful to do a divide here. If the cycle count becomes
1523 * important here, tricks can be pulled to reduce it. (However, it's
1524 * critical that hash collisions be kept to an absolute minimum;
1525 * they're much more painful than a divide.) It's better to have a
1526 * solution that generates few collisions and still keeps things
1527 * relatively simple.
1528 */
1529 bucket = hashval % dstate->dtds_hashsize;
1530
1531 if (op == DTRACE_DYNVAR_DEALLOC) {
1532 volatile uintptr_t *lockp = &hash[bucket].dtdh_lock;
1533
1534 for (;;) {
1535 while ((lock = *lockp) & 1)
1536 continue;
1537
1538 if (dtrace_casptr((void *)lockp,
1539 (void *)lock, (void *)(lock + 1)) == (void *)lock)
1540 break;
1541 }
1542
1543 dtrace_membar_producer();
1544 }
1545
1546 top:
1547 prev = NULL;
1548 lock = hash[bucket].dtdh_lock;
1549
1550 dtrace_membar_consumer();
1551
1552 start = hash[bucket].dtdh_chain;
1553 ASSERT(start != NULL && (start->dtdv_hashval == DTRACE_DYNHASH_SINK ||
1554 start->dtdv_hashval != DTRACE_DYNHASH_FREE ||
1555 op != DTRACE_DYNVAR_DEALLOC));
1556
1557 for (dvar = start; dvar != NULL; dvar = dvar->dtdv_next) {
1558 dtrace_tuple_t *dtuple = &dvar->dtdv_tuple;
1559 dtrace_key_t *dkey = &dtuple->dtt_key[0];
1560
1561 if (dvar->dtdv_hashval != hashval) {
1562 if (dvar->dtdv_hashval == DTRACE_DYNHASH_SINK) {
1563 /*
1564 * We've reached the sink, and therefore the
1565 * end of the hash chain; we can kick out of
1566 * the loop knowing that we have seen a valid
1567 * snapshot of state.
1568 */
1569 ASSERT(dvar->dtdv_next == NULL);
1570 ASSERT(dvar == &dtrace_dynhash_sink);
1571 break;
1572 }
1573
1574 if (dvar->dtdv_hashval == DTRACE_DYNHASH_FREE) {
1575 /*
1576 * We've gone off the rails: somewhere along
1577 * the line, one of the members of this hash
1578 * chain was deleted. Note that we could also
1579 * detect this by simply letting this loop run
1580 * to completion, as we would eventually hit
1581 * the end of the dirty list. However, we
1582 * want to avoid running the length of the
1583 * dirty list unnecessarily (it might be quite
1584 * long), so we catch this as early as
1585 * possible by detecting the hash marker. In
1586 * this case, we simply set dvar to NULL and
1587 * break; the conditional after the loop will
1588 * send us back to top.
1589 */
1590 dvar = NULL;
1591 break;
1592 }
1593
1594 goto next;
1595 }
1596
1597 if (dtuple->dtt_nkeys != nkeys)
1598 goto next;
1599
1600 for (i = 0; i < nkeys; i++, dkey++) {
1601 if (dkey->dttk_size != key[i].dttk_size)
1602 goto next; /* size or type mismatch */
1603
1604 if (dkey->dttk_size != 0) {
1605 if (dtrace_bcmp(
1606 (void *)(uintptr_t)key[i].dttk_value,
1607 (void *)(uintptr_t)dkey->dttk_value,
1608 dkey->dttk_size))
1609 goto next;
1610 } else {
1611 if (dkey->dttk_value != key[i].dttk_value)
1612 goto next;
1613 }
1614 }
1615
1616 if (op != DTRACE_DYNVAR_DEALLOC)
1617 return (dvar);
1618
1619 ASSERT(dvar->dtdv_next == NULL ||
1620 dvar->dtdv_next->dtdv_hashval != DTRACE_DYNHASH_FREE);
1621
1622 if (prev != NULL) {
1623 ASSERT(hash[bucket].dtdh_chain != dvar);
1624 ASSERT(start != dvar);
1625 ASSERT(prev->dtdv_next == dvar);
1626 prev->dtdv_next = dvar->dtdv_next;
1627 } else {
1628 if (dtrace_casptr(&hash[bucket].dtdh_chain,
1629 start, dvar->dtdv_next) != start) {
1630 /*
1631 * We have failed to atomically swing the
1632 * hash table head pointer, presumably because
1633 * of a conflicting allocation on another CPU.
1634 * We need to reread the hash chain and try
1635 * again.
1636 */
1637 goto top;
1638 }
1639 }
1640
1641 dtrace_membar_producer();
1642
1643 /*
1644 * Now set the hash value to indicate that it's free.
1645 */
1646 ASSERT(hash[bucket].dtdh_chain != dvar);
1647 dvar->dtdv_hashval = DTRACE_DYNHASH_FREE;
1648
1649 dtrace_membar_producer();
1650
1651 /*
1652 * Set the next pointer to point at the dirty list, and
1653 * atomically swing the dirty pointer to the newly freed dvar.
1654 */
1655 do {
1656 next = dcpu->dtdsc_dirty;
1657 dvar->dtdv_next = next;
1658 } while (dtrace_casptr(&dcpu->dtdsc_dirty, next, dvar) != next);
1659
1660 /*
1661 * Finally, unlock this hash bucket.
1662 */
1663 ASSERT(hash[bucket].dtdh_lock == lock);
1664 ASSERT(lock & 1);
1665 hash[bucket].dtdh_lock++;
1666
1667 return (NULL);
1668 next:
1669 prev = dvar;
1670 continue;
1671 }
1672
1673 if (dvar == NULL) {
1674 /*
1675 * If dvar is NULL, it is because we went off the rails:
1676 * one of the elements that we traversed in the hash chain
1677 * was deleted while we were traversing it. In this case,
1678 * we assert that we aren't doing a dealloc (deallocs lock
1679 * the hash bucket to prevent themselves from racing with
1680 * one another), and retry the hash chain traversal.
1681 */
1682 ASSERT(op != DTRACE_DYNVAR_DEALLOC);
1683 goto top;
1684 }
1685
1686 if (op != DTRACE_DYNVAR_ALLOC) {
1687 /*
1688 * If we are not to allocate a new variable, we want to
1689 * return NULL now. Before we return, check that the value
1690 * of the lock word hasn't changed. If it has, we may have
1691 * seen an inconsistent snapshot.
1692 */
1693 if (op == DTRACE_DYNVAR_NOALLOC) {
1694 if (hash[bucket].dtdh_lock != lock)
1695 goto top;
1696 } else {
1697 ASSERT(op == DTRACE_DYNVAR_DEALLOC);
1698 ASSERT(hash[bucket].dtdh_lock == lock);
1699 ASSERT(lock & 1);
1700 hash[bucket].dtdh_lock++;
1701 }
1702
1703 return (NULL);
1704 }
1705
1706 /*
1707 * We need to allocate a new dynamic variable. The size we need is the
1708 * size of dtrace_dynvar plus the size of nkeys dtrace_key_t's plus the
1709 * size of any auxiliary key data (rounded up to 8-byte alignment) plus
1710 * the size of any referred-to data (dsize). We then round the final
1711 * size up to the chunksize for allocation.
1712 */
1713 for (ksize = 0, i = 0; i < nkeys; i++)
1714 ksize += P2ROUNDUP(key[i].dttk_size, sizeof (uint64_t));
1715
1716 /*
1717 * This should be pretty much impossible, but could happen if, say,
1718 * strange DIF specified the tuple. Ideally, this should be an
1719 * assertion and not an error condition -- but that requires that the
1720 * chunksize calculation in dtrace_difo_chunksize() be absolutely
1721 * bullet-proof. (That is, it must not be able to be fooled by
1722 * malicious DIF.) Given the lack of backwards branches in DIF,
1723 * solving this would presumably not amount to solving the Halting
1724 * Problem -- but it still seems awfully hard.
1725 */
1726 if (sizeof (dtrace_dynvar_t) + sizeof (dtrace_key_t) * (nkeys - 1) +
1727 ksize + dsize > chunksize) {
1728 dcpu->dtdsc_drops++;
1729 return (NULL);
1730 }
1731
1732 nstate = DTRACE_DSTATE_EMPTY;
1733
1734 do {
1735 retry:
1736 free = dcpu->dtdsc_free;
1737
1738 if (free == NULL) {
1739 dtrace_dynvar_t *clean = dcpu->dtdsc_clean;
1740 void *rval;
1741
1742 if (clean == NULL) {
1743 /*
1744 * We're out of dynamic variable space on
1745 * this CPU. Unless we have tried all CPUs,
1746 * we'll try to allocate from a different
1747 * CPU.
1748 */
1749 switch (dstate->dtds_state) {
1750 case DTRACE_DSTATE_CLEAN: {
1751 void *sp = &dstate->dtds_state;
1752
1753 if (++cpu >= NCPU)
1754 cpu = 0;
1755
1756 if (dcpu->dtdsc_dirty != NULL &&
1757 nstate == DTRACE_DSTATE_EMPTY)
1758 nstate = DTRACE_DSTATE_DIRTY;
1759
1760 if (dcpu->dtdsc_rinsing != NULL)
1761 nstate = DTRACE_DSTATE_RINSING;
1762
1763 dcpu = &dstate->dtds_percpu[cpu];
1764
1765 if (cpu != me)
1766 goto retry;
1767
1768 (void) dtrace_cas32(sp,
1769 DTRACE_DSTATE_CLEAN, nstate);
1770
1771 /*
1772 * To increment the correct bean
1773 * counter, take another lap.
1774 */
1775 goto retry;
1776 }
1777
1778 case DTRACE_DSTATE_DIRTY:
1779 dcpu->dtdsc_dirty_drops++;
1780 break;
1781
1782 case DTRACE_DSTATE_RINSING:
1783 dcpu->dtdsc_rinsing_drops++;
1784 break;
1785
1786 case DTRACE_DSTATE_EMPTY:
1787 dcpu->dtdsc_drops++;
1788 break;
1789 }
1790
1791 DTRACE_CPUFLAG_SET(CPU_DTRACE_DROP);
1792 return (NULL);
1793 }
1794
1795 /*
1796 * The clean list appears to be non-empty. We want to
1797 * move the clean list to the free list; we start by
1798 * moving the clean pointer aside.
1799 */
1800 if (dtrace_casptr(&dcpu->dtdsc_clean,
1801 clean, NULL) != clean) {
1802 /*
1803 * We are in one of two situations:
1804 *
1805 * (a) The clean list was switched to the
1806 * free list by another CPU.
1807 *
1808 * (b) The clean list was added to by the
1809 * cleansing cyclic.
1810 *
1811 * In either of these situations, we can
1812 * just reattempt the free list allocation.
1813 */
1814 goto retry;
1815 }
1816
1817 ASSERT(clean->dtdv_hashval == DTRACE_DYNHASH_FREE);
1818
1819 /*
1820 * Now we'll move the clean list to our free list.
1821 * It's impossible for this to fail: the only way
1822 * the free list can be updated is through this
1823 * code path, and only one CPU can own the clean list.
1824 * Thus, it would only be possible for this to fail if
1825 * this code were racing with dtrace_dynvar_clean().
1826 * (That is, if dtrace_dynvar_clean() updated the clean
1827 * list, and we ended up racing to update the free
1828 * list.) This race is prevented by the dtrace_sync()
1829 * in dtrace_dynvar_clean() -- which flushes the
1830 * owners of the clean lists out before resetting
1831 * the clean lists.
1832 */
1833 dcpu = &dstate->dtds_percpu[me];
1834 rval = dtrace_casptr(&dcpu->dtdsc_free, NULL, clean);
1835 ASSERT(rval == NULL);
1836 goto retry;
1837 }
1838
1839 dvar = free;
1840 new_free = dvar->dtdv_next;
1841 } while (dtrace_casptr(&dcpu->dtdsc_free, free, new_free) != free);
1842
1843 /*
1844 * We have now allocated a new chunk. We copy the tuple keys into the
1845 * tuple array and copy any referenced key data into the data space
1846 * following the tuple array. As we do this, we relocate dttk_value
1847 * in the final tuple to point to the key data address in the chunk.
1848 */
1849 kdata = (uintptr_t)&dvar->dtdv_tuple.dtt_key[nkeys];
1850 dvar->dtdv_data = (void *)(kdata + ksize);
1851 dvar->dtdv_tuple.dtt_nkeys = nkeys;
1852
1853 for (i = 0; i < nkeys; i++) {
1854 dtrace_key_t *dkey = &dvar->dtdv_tuple.dtt_key[i];
1855 size_t kesize = key[i].dttk_size;
1856
1857 if (kesize != 0) {
1858 dtrace_bcopy(
1859 (const void *)(uintptr_t)key[i].dttk_value,
1860 (void *)kdata, kesize);
1861 dkey->dttk_value = kdata;
1862 kdata += P2ROUNDUP(kesize, sizeof (uint64_t));
1863 } else {
1864 dkey->dttk_value = key[i].dttk_value;
1865 }
1866
1867 dkey->dttk_size = kesize;
1868 }
1869
1870 ASSERT(dvar->dtdv_hashval == DTRACE_DYNHASH_FREE);
1871 dvar->dtdv_hashval = hashval;
1872 dvar->dtdv_next = start;
1873
1874 if (dtrace_casptr(&hash[bucket].dtdh_chain, start, dvar) == start)
1875 return (dvar);
1876
1877 /*
1878 * The cas has failed. Either another CPU is adding an element to
1879 * this hash chain, or another CPU is deleting an element from this
1880 * hash chain. The simplest way to deal with both of these cases
1881 * (though not necessarily the most efficient) is to free our
1882 * allocated block and tail-call ourselves. Note that the free is
1883 * to the dirty list and _not_ to the free list. This is to prevent
1884 * races with allocators, above.
1885 */
1886 dvar->dtdv_hashval = DTRACE_DYNHASH_FREE;
1887
1888 dtrace_membar_producer();
1889
1890 do {
1891 free = dcpu->dtdsc_dirty;
1892 dvar->dtdv_next = free;
1893 } while (dtrace_casptr(&dcpu->dtdsc_dirty, free, dvar) != free);
1894
1895 return (dtrace_dynvar(dstate, nkeys, key, dsize, op, mstate, vstate));
1896 }
1897
1898 /*ARGSUSED*/
1899 static void
1900 dtrace_aggregate_min(uint64_t *oval, uint64_t nval, uint64_t arg)
1901 {
1902 if ((int64_t)nval < (int64_t)*oval)
1903 *oval = nval;
1904 }
1905
1906 /*ARGSUSED*/
1907 static void
1908 dtrace_aggregate_max(uint64_t *oval, uint64_t nval, uint64_t arg)
1909 {
1910 if ((int64_t)nval > (int64_t)*oval)
1911 *oval = nval;
1912 }
1913
1914 static void
1915 dtrace_aggregate_quantize(uint64_t *quanta, uint64_t nval, uint64_t incr)
1916 {
1917 int i, zero = DTRACE_QUANTIZE_ZEROBUCKET;
1918 int64_t val = (int64_t)nval;
1919
1920 if (val < 0) {
1921 for (i = 0; i < zero; i++) {
1922 if (val <= DTRACE_QUANTIZE_BUCKETVAL(i)) {
1923 quanta[i] += incr;
1924 return;
1925 }
1926 }
1927 } else {
1928 for (i = zero + 1; i < DTRACE_QUANTIZE_NBUCKETS; i++) {
1929 if (val < DTRACE_QUANTIZE_BUCKETVAL(i)) {
1930 quanta[i - 1] += incr;
1931 return;
1932 }
1933 }
1934
1935 quanta[DTRACE_QUANTIZE_NBUCKETS - 1] += incr;
1936 return;
1937 }
1938
1939 ASSERT(0);
1940 }
1941
1942 static void
1943 dtrace_aggregate_lquantize(uint64_t *lquanta, uint64_t nval, uint64_t incr)
1944 {
1945 uint64_t arg = *lquanta++;
1946 int32_t base = DTRACE_LQUANTIZE_BASE(arg);
1947 uint16_t step = DTRACE_LQUANTIZE_STEP(arg);
1948 uint16_t levels = DTRACE_LQUANTIZE_LEVELS(arg);
1949 int32_t val = (int32_t)nval, level;
1950
1951 ASSERT(step != 0);
1952 ASSERT(levels != 0);
1953
1954 if (val < base) {
1955 /*
1956 * This is an underflow.
1957 */
1958 lquanta[0] += incr;
1959 return;
1960 }
1961
1962 level = (val - base) / step;
1963
1964 if (level < levels) {
1965 lquanta[level + 1] += incr;
1966 return;
1967 }
1968
1969 /*
1970 * This is an overflow.
1971 */
1972 lquanta[levels + 1] += incr;
1973 }
1974
1975 static int
1976 dtrace_aggregate_llquantize_bucket(uint16_t factor, uint16_t low,
1977 uint16_t high, uint16_t nsteps, int64_t value)
1978 {
1979 int64_t this = 1, last, next;
1980 int base = 1, order;
1981
1982 ASSERT(factor <= nsteps);
1983 ASSERT(nsteps % factor == 0);
1984
1985 for (order = 0; order < low; order++)
1986 this *= factor;
1987
1988 /*
1989 * If our value is less than our factor taken to the power of the
1990 * low order of magnitude, it goes into the zeroth bucket.
1991 */
1992 if (value < (last = this))
1993 return (0);
1994
1995 for (this *= factor; order <= high; order++) {
1996 int nbuckets = this > nsteps ? nsteps : this;
1997
1998 if ((next = this * factor) < this) {
1999 /*
2000 * We should not generally get log/linear quantizations
2001 * with a high magnitude that allows 64-bits to
2002 * overflow, but we nonetheless protect against this
2003 * by explicitly checking for overflow, and clamping
2004 * our value accordingly.
2005 */
2006 value = this - 1;
2007 }
2008
2009 if (value < this) {
2010 /*
2011 * If our value lies within this order of magnitude,
2012 * determine its position by taking the offset within
2013 * the order of magnitude, dividing by the bucket
2014 * width, and adding to our (accumulated) base.
2015 */
2016 return (base + (value - last) / (this / nbuckets));
2017 }
2018
2019 base += nbuckets - (nbuckets / factor);
2020 last = this;
2021 this = next;
2022 }
2023
2024 /*
2025 * Our value is greater than or equal to our factor taken to the
2026 * power of one plus the high magnitude -- return the top bucket.
2027 */
2028 return (base);
2029 }
2030
2031 static void
2032 dtrace_aggregate_llquantize(uint64_t *llquanta, uint64_t nval, uint64_t incr)
2033 {
2034 uint64_t arg = *llquanta++;
2035 uint16_t factor = DTRACE_LLQUANTIZE_FACTOR(arg);
2036 uint16_t low = DTRACE_LLQUANTIZE_LOW(arg);
2037 uint16_t high = DTRACE_LLQUANTIZE_HIGH(arg);
2038 uint16_t nsteps = DTRACE_LLQUANTIZE_NSTEP(arg);
2039
2040 llquanta[dtrace_aggregate_llquantize_bucket(factor,
2041 low, high, nsteps, nval)] += incr;
2042 }
2043
2044 /*ARGSUSED*/
2045 static void
2046 dtrace_aggregate_avg(uint64_t *data, uint64_t nval, uint64_t arg)
2047 {
2048 data[0]++;
2049 data[1] += nval;
2050 }
2051
2052 /*ARGSUSED*/
2053 static void
2054 dtrace_aggregate_stddev(uint64_t *data, uint64_t nval, uint64_t arg)
2055 {
2056 int64_t snval = (int64_t)nval;
2057 uint64_t tmp[2];
2058
2059 data[0]++;
2060 data[1] += nval;
2061
2062 /*
2063 * What we want to say here is:
2064 *
2065 * data[2] += nval * nval;
2066 *
2067 * But given that nval is 64-bit, we could easily overflow, so
2068 * we do this as 128-bit arithmetic.
2069 */
2070 if (snval < 0)
2071 snval = -snval;
2072
2073 dtrace_multiply_128((uint64_t)snval, (uint64_t)snval, tmp);
2074 dtrace_add_128(data + 2, tmp, data + 2);
2075 }
2076
2077 /*ARGSUSED*/
2078 static void
2079 dtrace_aggregate_count(uint64_t *oval, uint64_t nval, uint64_t arg)
2080 {
2081 *oval = *oval + 1;
2082 }
2083
2084 /*ARGSUSED*/
2085 static void
2086 dtrace_aggregate_sum(uint64_t *oval, uint64_t nval, uint64_t arg)
2087 {
2088 *oval += nval;
2089 }
2090
2091 /*
2092 * Aggregate given the tuple in the principal data buffer, and the aggregating
2093 * action denoted by the specified dtrace_aggregation_t. The aggregation
2094 * buffer is specified as the buf parameter. This routine does not return
2095 * failure; if there is no space in the aggregation buffer, the data will be
2096 * dropped, and a corresponding counter incremented.
2097 */
2098 static void
2099 dtrace_aggregate(dtrace_aggregation_t *agg, dtrace_buffer_t *dbuf,
2100 intptr_t offset, dtrace_buffer_t *buf, uint64_t expr, uint64_t arg)
2101 {
2102 dtrace_recdesc_t *rec = &agg->dtag_action.dta_rec;
2103 uint32_t i, ndx, size, fsize;
2104 uint32_t align = sizeof (uint64_t) - 1;
2105 dtrace_aggbuffer_t *agb;
2106 dtrace_aggkey_t *key;
2107 uint32_t hashval = 0, limit, isstr;
2108 caddr_t tomax, data, kdata;
2109 dtrace_actkind_t action;
2110 dtrace_action_t *act;
2111 uintptr_t offs;
2112
2113 if (buf == NULL)
2114 return;
2115
2116 if (!agg->dtag_hasarg) {
2117 /*
2118 * Currently, only quantize() and lquantize() take additional
2119 * arguments, and they have the same semantics: an increment
2120 * value that defaults to 1 when not present. If additional
2121 * aggregating actions take arguments, the setting of the
2122 * default argument value will presumably have to become more
2123 * sophisticated...
2124 */
2125 arg = 1;
2126 }
2127
2128 action = agg->dtag_action.dta_kind - DTRACEACT_AGGREGATION;
2129 size = rec->dtrd_offset - agg->dtag_base;
2130 fsize = size + rec->dtrd_size;
2131
2132 ASSERT(dbuf->dtb_tomax != NULL);
2133 data = dbuf->dtb_tomax + offset + agg->dtag_base;
2134
2135 if ((tomax = buf->dtb_tomax) == NULL) {
2136 dtrace_buffer_drop(buf);
2137 return;
2138 }
2139
2140 /*
2141 * The metastructure is always at the bottom of the buffer.
2142 */
2143 agb = (dtrace_aggbuffer_t *)(tomax + buf->dtb_size -
2144 sizeof (dtrace_aggbuffer_t));
2145
2146 if (buf->dtb_offset == 0) {
2147 /*
2148 * We just kludge up approximately 1/8th of the size to be
2149 * buckets. If this guess ends up being routinely
2150 * off-the-mark, we may need to dynamically readjust this
2151 * based on past performance.
2152 */
2153 uintptr_t hashsize = (buf->dtb_size >> 3) / sizeof (uintptr_t);
2154
2155 if ((uintptr_t)agb - hashsize * sizeof (dtrace_aggkey_t *) <
2156 (uintptr_t)tomax || hashsize == 0) {
2157 /*
2158 * We've been given a ludicrously small buffer;
2159 * increment our drop count and leave.
2160 */
2161 dtrace_buffer_drop(buf);
2162 return;
2163 }
2164
2165 /*
2166 * And now, a pathetic attempt to try to get a an odd (or
2167 * perchance, a prime) hash size for better hash distribution.
2168 */
2169 if (hashsize > (DTRACE_AGGHASHSIZE_SLEW << 3))
2170 hashsize -= DTRACE_AGGHASHSIZE_SLEW;
2171
2172 agb->dtagb_hashsize = hashsize;
2173 agb->dtagb_hash = (dtrace_aggkey_t **)((uintptr_t)agb -
2174 agb->dtagb_hashsize * sizeof (dtrace_aggkey_t *));
2175 agb->dtagb_free = (uintptr_t)agb->dtagb_hash;
2176
2177 for (i = 0; i < agb->dtagb_hashsize; i++)
2178 agb->dtagb_hash[i] = NULL;
2179 }
2180
2181 ASSERT(agg->dtag_first != NULL);
2182 ASSERT(agg->dtag_first->dta_intuple);
2183
2184 /*
2185 * Calculate the hash value based on the key. Note that we _don't_
2186 * include the aggid in the hashing (but we will store it as part of
2187 * the key). The hashing algorithm is Bob Jenkins' "One-at-a-time"
2188 * algorithm: a simple, quick algorithm that has no known funnels, and
2189 * gets good distribution in practice. The efficacy of the hashing
2190 * algorithm (and a comparison with other algorithms) may be found by
2191 * running the ::dtrace_aggstat MDB dcmd.
2192 */
2193 for (act = agg->dtag_first; act->dta_intuple; act = act->dta_next) {
2194 i = act->dta_rec.dtrd_offset - agg->dtag_base;
2195 limit = i + act->dta_rec.dtrd_size;
2196 ASSERT(limit <= size);
2197 isstr = DTRACEACT_ISSTRING(act);
2198
2199 for (; i < limit; i++) {
2200 hashval += data[i];
2201 hashval += (hashval << 10);
2202 hashval ^= (hashval >> 6);
2203
2204 if (isstr && data[i] == '\0')
2205 break;
2206 }
2207 }
2208
2209 hashval += (hashval << 3);
2210 hashval ^= (hashval >> 11);
2211 hashval += (hashval << 15);
2212
2213 /*
2214 * Yes, the divide here is expensive -- but it's generally the least
2215 * of the performance issues given the amount of data that we iterate
2216 * over to compute hash values, compare data, etc.
2217 */
2218 ndx = hashval % agb->dtagb_hashsize;
2219
2220 for (key = agb->dtagb_hash[ndx]; key != NULL; key = key->dtak_next) {
2221 ASSERT((caddr_t)key >= tomax);
2222 ASSERT((caddr_t)key < tomax + buf->dtb_size);
2223
2224 if (hashval != key->dtak_hashval || key->dtak_size != size)
2225 continue;
2226
2227 kdata = key->dtak_data;
2228 ASSERT(kdata >= tomax && kdata < tomax + buf->dtb_size);
2229
2230 for (act = agg->dtag_first; act->dta_intuple;
2231 act = act->dta_next) {
2232 i = act->dta_rec.dtrd_offset - agg->dtag_base;
2233 limit = i + act->dta_rec.dtrd_size;
2234 ASSERT(limit <= size);
2235 isstr = DTRACEACT_ISSTRING(act);
2236
2237 for (; i < limit; i++) {
2238 if (kdata[i] != data[i])
2239 goto next;
2240
2241 if (isstr && data[i] == '\0')
2242 break;
2243 }
2244 }
2245
2246 if (action != key->dtak_action) {
2247 /*
2248 * We are aggregating on the same value in the same
2249 * aggregation with two different aggregating actions.
2250 * (This should have been picked up in the compiler,
2251 * so we may be dealing with errant or devious DIF.)
2252 * This is an error condition; we indicate as much,
2253 * and return.
2254 */
2255 DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP);
2256 return;
2257 }
2258
2259 /*
2260 * This is a hit: we need to apply the aggregator to
2261 * the value at this key.
2262 */
2263 agg->dtag_aggregate((uint64_t *)(kdata + size), expr, arg);
2264 return;
2265 next:
2266 continue;
2267 }
2268
2269 /*
2270 * We didn't find it. We need to allocate some zero-filled space,
2271 * link it into the hash table appropriately, and apply the aggregator
2272 * to the (zero-filled) value.
2273 */
2274 offs = buf->dtb_offset;
2275 while (offs & (align - 1))
2276 offs += sizeof (uint32_t);
2277
2278 /*
2279 * If we don't have enough room to both allocate a new key _and_
2280 * its associated data, increment the drop count and return.
2281 */
2282 if ((uintptr_t)tomax + offs + fsize >
2283 agb->dtagb_free - sizeof (dtrace_aggkey_t)) {
2284 dtrace_buffer_drop(buf);
2285 return;
2286 }
2287
2288 /*CONSTCOND*/
2289 ASSERT(!(sizeof (dtrace_aggkey_t) & (sizeof (uintptr_t) - 1)));
2290 key = (dtrace_aggkey_t *)(agb->dtagb_free - sizeof (dtrace_aggkey_t));
2291 agb->dtagb_free -= sizeof (dtrace_aggkey_t);
2292
2293 key->dtak_data = kdata = tomax + offs;
2294 buf->dtb_offset = offs + fsize;
2295
2296 /*
2297 * Now copy the data across.
2298 */
2299 *((dtrace_aggid_t *)kdata) = agg->dtag_id;
2300
2301 for (i = sizeof (dtrace_aggid_t); i < size; i++)
2302 kdata[i] = data[i];
2303
2304 /*
2305 * Because strings are not zeroed out by default, we need to iterate
2306 * looking for actions that store strings, and we need to explicitly
2307 * pad these strings out with zeroes.
2308 */
2309 for (act = agg->dtag_first; act->dta_intuple; act = act->dta_next) {
2310 int nul;
2311
2312 if (!DTRACEACT_ISSTRING(act))
2313 continue;
2314
2315 i = act->dta_rec.dtrd_offset - agg->dtag_base;
2316 limit = i + act->dta_rec.dtrd_size;
2317 ASSERT(limit <= size);
2318
2319 for (nul = 0; i < limit; i++) {
2320 if (nul) {
2321 kdata[i] = '\0';
2322 continue;
2323 }
2324
2325 if (data[i] != '\0')
2326 continue;
2327
2328 nul = 1;
2329 }
2330 }
2331
2332 for (i = size; i < fsize; i++)
2333 kdata[i] = 0;
2334
2335 key->dtak_hashval = hashval;
2336 key->dtak_size = size;
2337 key->dtak_action = action;
2338 key->dtak_next = agb->dtagb_hash[ndx];
2339 agb->dtagb_hash[ndx] = key;
2340
2341 /*
2342 * Finally, apply the aggregator.
2343 */
2344 *((uint64_t *)(key->dtak_data + size)) = agg->dtag_initial;
2345 agg->dtag_aggregate((uint64_t *)(key->dtak_data + size), expr, arg);
2346 }
2347
2348 /*
2349 * Given consumer state, this routine finds a speculation in the INACTIVE
2350 * state and transitions it into the ACTIVE state. If there is no speculation
2351 * in the INACTIVE state, 0 is returned. In this case, no error counter is
2352 * incremented -- it is up to the caller to take appropriate action.
2353 */
2354 static int
2355 dtrace_speculation(dtrace_state_t *state)
2356 {
2357 int i = 0;
2358 dtrace_speculation_state_t current;
2359 uint32_t *stat = &state->dts_speculations_unavail, count;
2360
2361 while (i < state->dts_nspeculations) {
2362 dtrace_speculation_t *spec = &state->dts_speculations[i];
2363
2364 current = spec->dtsp_state;
2365
2366 if (current != DTRACESPEC_INACTIVE) {
2367 if (current == DTRACESPEC_COMMITTINGMANY ||
2368 current == DTRACESPEC_COMMITTING ||
2369 current == DTRACESPEC_DISCARDING)
2370 stat = &state->dts_speculations_busy;
2371 i++;
2372 continue;
2373 }
2374
2375 if (dtrace_cas32((uint32_t *)&spec->dtsp_state,
2376 current, DTRACESPEC_ACTIVE) == current)
2377 return (i + 1);
2378 }
2379
2380 /*
2381 * We couldn't find a speculation. If we found as much as a single
2382 * busy speculation buffer, we'll attribute this failure as "busy"
2383 * instead of "unavail".
2384 */
2385 do {
2386 count = *stat;
2387 } while (dtrace_cas32(stat, count, count + 1) != count);
2388
2389 return (0);
2390 }
2391
2392 /*
2393 * This routine commits an active speculation. If the specified speculation
2394 * is not in a valid state to perform a commit(), this routine will silently do
2395 * nothing. The state of the specified speculation is transitioned according
2396 * to the state transition diagram outlined in <sys/dtrace_impl.h>
2397 */
2398 static void
2399 dtrace_speculation_commit(dtrace_state_t *state, processorid_t cpu,
2400 dtrace_specid_t which)
2401 {
2402 dtrace_speculation_t *spec;
2403 dtrace_buffer_t *src, *dest;
2404 uintptr_t daddr, saddr, dlimit;
2405 dtrace_speculation_state_t current, new;
2406 intptr_t offs;
2407
2408 if (which == 0)
2409 return;
2410
2411 if (which > state->dts_nspeculations) {
2412 cpu_core[cpu].cpuc_dtrace_flags |= CPU_DTRACE_ILLOP;
2413 return;
2414 }
2415
2416 spec = &state->dts_speculations[which - 1];
2417 src = &spec->dtsp_buffer[cpu];
2418 dest = &state->dts_buffer[cpu];
2419
2420 do {
2421 current = spec->dtsp_state;
2422
2423 if (current == DTRACESPEC_COMMITTINGMANY)
2424 break;
2425
2426 switch (current) {
2427 case DTRACESPEC_INACTIVE:
2428 case DTRACESPEC_DISCARDING:
2429 return;
2430
2431 case DTRACESPEC_COMMITTING:
2432 /*
2433 * This is only possible if we are (a) commit()'ing
2434 * without having done a prior speculate() on this CPU
2435 * and (b) racing with another commit() on a different
2436 * CPU. There's nothing to do -- we just assert that
2437 * our offset is 0.
2438 */
2439 ASSERT(src->dtb_offset == 0);
2440 return;
2441
2442 case DTRACESPEC_ACTIVE:
2443 new = DTRACESPEC_COMMITTING;
2444 break;
2445
2446 case DTRACESPEC_ACTIVEONE:
2447 /*
2448 * This speculation is active on one CPU. If our
2449 * buffer offset is non-zero, we know that the one CPU
2450 * must be us. Otherwise, we are committing on a
2451 * different CPU from the speculate(), and we must
2452 * rely on being asynchronously cleaned.
2453 */
2454 if (src->dtb_offset != 0) {
2455 new = DTRACESPEC_COMMITTING;
2456 break;
2457 }
2458 /*FALLTHROUGH*/
2459
2460 case DTRACESPEC_ACTIVEMANY:
2461 new = DTRACESPEC_COMMITTINGMANY;
2462 break;
2463
2464 default:
2465 ASSERT(0);
2466 }
2467 } while (dtrace_cas32((uint32_t *)&spec->dtsp_state,
2468 current, new) != current);
2469
2470 /*
2471 * We have set the state to indicate that we are committing this
2472 * speculation. Now reserve the necessary space in the destination
2473 * buffer.
2474 */
2475 if ((offs = dtrace_buffer_reserve(dest, src->dtb_offset,
2476 sizeof (uint64_t), state, NULL)) < 0) {
2477 dtrace_buffer_drop(dest);
2478 goto out;
2479 }
2480
2481 /*
2482 * We have the space; copy the buffer across. (Note that this is a
2483 * highly subobtimal bcopy(); in the unlikely event that this becomes
2484 * a serious performance issue, a high-performance DTrace-specific
2485 * bcopy() should obviously be invented.)
2486 */
2487 daddr = (uintptr_t)dest->dtb_tomax + offs;
2488 dlimit = daddr + src->dtb_offset;
2489 saddr = (uintptr_t)src->dtb_tomax;
2490
2491 /*
2492 * First, the aligned portion.
2493 */
2494 while (dlimit - daddr >= sizeof (uint64_t)) {
2495 *((uint64_t *)daddr) = *((uint64_t *)saddr);
2496
2497 daddr += sizeof (uint64_t);
2498 saddr += sizeof (uint64_t);
2499 }
2500
2501 /*
2502 * Now any left-over bit...
2503 */
2504 while (dlimit - daddr)
2505 *((uint8_t *)daddr++) = *((uint8_t *)saddr++);
2506
2507 /*
2508 * Finally, commit the reserved space in the destination buffer.
2509 */
2510 dest->dtb_offset = offs + src->dtb_offset;
2511
2512 out:
2513 /*
2514 * If we're lucky enough to be the only active CPU on this speculation
2515 * buffer, we can just set the state back to DTRACESPEC_INACTIVE.
2516 */
2517 if (current == DTRACESPEC_ACTIVE ||
2518 (current == DTRACESPEC_ACTIVEONE && new == DTRACESPEC_COMMITTING)) {
2519 uint32_t rval = dtrace_cas32((uint32_t *)&spec->dtsp_state,
2520 DTRACESPEC_COMMITTING, DTRACESPEC_INACTIVE);
2521
2522 ASSERT(rval == DTRACESPEC_COMMITTING);
2523 }
2524
2525 src->dtb_offset = 0;
2526 src->dtb_xamot_drops += src->dtb_drops;
2527 src->dtb_drops = 0;
2528 }
2529
2530 /*
2531 * This routine discards an active speculation. If the specified speculation
2532 * is not in a valid state to perform a discard(), this routine will silently
2533 * do nothing. The state of the specified speculation is transitioned
2534 * according to the state transition diagram outlined in <sys/dtrace_impl.h>
2535 */
2536 static void
2537 dtrace_speculation_discard(dtrace_state_t *state, processorid_t cpu,
2538 dtrace_specid_t which)
2539 {
2540 dtrace_speculation_t *spec;
2541 dtrace_speculation_state_t current, new;
2542 dtrace_buffer_t *buf;
2543
2544 if (which == 0)
2545 return;
2546
2547 if (which > state->dts_nspeculations) {
2548 cpu_core[cpu].cpuc_dtrace_flags |= CPU_DTRACE_ILLOP;
2549 return;
2550 }
2551
2552 spec = &state->dts_speculations[which - 1];
2553 buf = &spec->dtsp_buffer[cpu];
2554
2555 do {
2556 current = spec->dtsp_state;
2557
2558 switch (current) {
2559 case DTRACESPEC_INACTIVE:
2560 case DTRACESPEC_COMMITTINGMANY:
2561 case DTRACESPEC_COMMITTING:
2562 case DTRACESPEC_DISCARDING:
2563 return;
2564
2565 case DTRACESPEC_ACTIVE:
2566 case DTRACESPEC_ACTIVEMANY:
2567 new = DTRACESPEC_DISCARDING;
2568 break;
2569
2570 case DTRACESPEC_ACTIVEONE:
2571 if (buf->dtb_offset != 0) {
2572 new = DTRACESPEC_INACTIVE;
2573 } else {
2574 new = DTRACESPEC_DISCARDING;
2575 }
2576 break;
2577
2578 default:
2579 ASSERT(0);
2580 }
2581 } while (dtrace_cas32((uint32_t *)&spec->dtsp_state,
2582 current, new) != current);
2583
2584 buf->dtb_offset = 0;
2585 buf->dtb_drops = 0;
2586 }
2587
2588 /*
2589 * Note: not called from probe context. This function is called
2590 * asynchronously from cross call context to clean any speculations that are
2591 * in the COMMITTINGMANY or DISCARDING states. These speculations may not be
2592 * transitioned back to the INACTIVE state until all CPUs have cleaned the
2593 * speculation.
2594 */
2595 static void
2596 dtrace_speculation_clean_here(dtrace_state_t *state)
2597 {
2598 dtrace_icookie_t cookie;
2599 processorid_t cpu = CPU->cpu_id;
2600 dtrace_buffer_t *dest = &state->dts_buffer[cpu];
2601 dtrace_specid_t i;
2602
2603 cookie = dtrace_interrupt_disable();
2604
2605 if (dest->dtb_tomax == NULL) {
2606 dtrace_interrupt_enable(cookie);
2607 return;
2608 }
2609
2610 for (i = 0; i < state->dts_nspeculations; i++) {
2611 dtrace_speculation_t *spec = &state->dts_speculations[i];
2612 dtrace_buffer_t *src = &spec->dtsp_buffer[cpu];
2613
2614 if (src->dtb_tomax == NULL)
2615 continue;
2616
2617 if (spec->dtsp_state == DTRACESPEC_DISCARDING) {
2618 src->dtb_offset = 0;
2619 continue;
2620 }
2621
2622 if (spec->dtsp_state != DTRACESPEC_COMMITTINGMANY)
2623 continue;
2624
2625 if (src->dtb_offset == 0)
2626 continue;
2627
2628 dtrace_speculation_commit(state, cpu, i + 1);
2629 }
2630
2631 dtrace_interrupt_enable(cookie);
2632 }
2633
2634 /*
2635 * Note: not called from probe context. This function is called
2636 * asynchronously (and at a regular interval) to clean any speculations that
2637 * are in the COMMITTINGMANY or DISCARDING states. If it discovers that there
2638 * is work to be done, it cross calls all CPUs to perform that work;
2639 * COMMITMANY and DISCARDING speculations may not be transitioned back to the
2640 * INACTIVE state until they have been cleaned by all CPUs.
2641 */
2642 static void
2643 dtrace_speculation_clean(dtrace_state_t *state)
2644 {
2645 int work = 0, rv;
2646 dtrace_specid_t i;
2647
2648 for (i = 0; i < state->dts_nspeculations; i++) {
2649 dtrace_speculation_t *spec = &state->dts_speculations[i];
2650
2651 ASSERT(!spec->dtsp_cleaning);
2652
2653 if (spec->dtsp_state != DTRACESPEC_DISCARDING &&
2654 spec->dtsp_state != DTRACESPEC_COMMITTINGMANY)
2655 continue;
2656
2657 work++;
2658 spec->dtsp_cleaning = 1;
2659 }
2660
2661 if (!work)
2662 return;
2663
2664 dtrace_xcall(DTRACE_CPUALL,
2665 (dtrace_xcall_t)dtrace_speculation_clean_here, state);
2666
2667 /*
2668 * We now know that all CPUs have committed or discarded their
2669 * speculation buffers, as appropriate. We can now set the state
2670 * to inactive.
2671 */
2672 for (i = 0; i < state->dts_nspeculations; i++) {
2673 dtrace_speculation_t *spec = &state->dts_speculations[i];
2674 dtrace_speculation_state_t current, new;
2675
2676 if (!spec->dtsp_cleaning)
2677 continue;
2678
2679 current = spec->dtsp_state;
2680 ASSERT(current == DTRACESPEC_DISCARDING ||
2681 current == DTRACESPEC_COMMITTINGMANY);
2682
2683 new = DTRACESPEC_INACTIVE;
2684
2685 rv = dtrace_cas32((uint32_t *)&spec->dtsp_state, current, new);
2686 ASSERT(rv == current);
2687 spec->dtsp_cleaning = 0;
2688 }
2689 }
2690
2691 /*
2692 * Called as part of a speculate() to get the speculative buffer associated
2693 * with a given speculation. Returns NULL if the specified speculation is not
2694 * in an ACTIVE state. If the speculation is in the ACTIVEONE state -- and
2695 * the active CPU is not the specified CPU -- the speculation will be
2696 * atomically transitioned into the ACTIVEMANY state.
2697 */
2698 static dtrace_buffer_t *
2699 dtrace_speculation_buffer(dtrace_state_t *state, processorid_t cpuid,
2700 dtrace_specid_t which)
2701 {
2702 dtrace_speculation_t *spec;
2703 dtrace_speculation_state_t current, new;
2704 dtrace_buffer_t *buf;
2705
2706 if (which == 0)
2707 return (NULL);
2708
2709 if (which > state->dts_nspeculations) {
2710 cpu_core[cpuid].cpuc_dtrace_flags |= CPU_DTRACE_ILLOP;
2711 return (NULL);
2712 }
2713
2714 spec = &state->dts_speculations[which - 1];
2715 buf = &spec->dtsp_buffer[cpuid];
2716
2717 do {
2718 current = spec->dtsp_state;
2719
2720 switch (current) {
2721 case DTRACESPEC_INACTIVE:
2722 case DTRACESPEC_COMMITTINGMANY:
2723 case DTRACESPEC_DISCARDING:
2724 return (NULL);
2725
2726 case DTRACESPEC_COMMITTING:
2727 ASSERT(buf->dtb_offset == 0);
2728 return (NULL);
2729
2730 case DTRACESPEC_ACTIVEONE:
2731 /*
2732 * This speculation is currently active on one CPU.
2733 * Check the offset in the buffer; if it's non-zero,
2734 * that CPU must be us (and we leave the state alone).
2735 * If it's zero, assume that we're starting on a new
2736 * CPU -- and change the state to indicate that the
2737 * speculation is active on more than one CPU.
2738 */
2739 if (buf->dtb_offset != 0)
2740 return (buf);
2741
2742 new = DTRACESPEC_ACTIVEMANY;
2743 break;
2744
2745 case DTRACESPEC_ACTIVEMANY:
2746 return (buf);
2747
2748 case DTRACESPEC_ACTIVE:
2749 new = DTRACESPEC_ACTIVEONE;
2750 break;
2751
2752 default:
2753 ASSERT(0);
2754 }
2755 } while (dtrace_cas32((uint32_t *)&spec->dtsp_state,
2756 current, new) != current);
2757
2758 ASSERT(new == DTRACESPEC_ACTIVEONE || new == DTRACESPEC_ACTIVEMANY);
2759 return (buf);
2760 }
2761
2762 /*
2763 * Return a string. In the event that the user lacks the privilege to access
2764 * arbitrary kernel memory, we copy the string out to scratch memory so that we
2765 * don't fail access checking.
2766 *
2767 * dtrace_dif_variable() uses this routine as a helper for various
2768 * builtin values such as 'execname' and 'probefunc.'
2769 */
2770 uintptr_t
2771 dtrace_dif_varstr(uintptr_t addr, dtrace_state_t *state,
2772 dtrace_mstate_t *mstate)
2773 {
2774 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
2775 uintptr_t ret;
2776 size_t strsz;
2777
2778 /*
2779 * The easy case: this probe is allowed to read all of memory, so
2780 * we can just return this as a vanilla pointer.
2781 */
2782 if ((mstate->dtms_access & DTRACE_ACCESS_KERNEL) != 0)
2783 return (addr);
2784
2785 /*
2786 * This is the tougher case: we copy the string in question from
2787 * kernel memory into scratch memory and return it that way: this
2788 * ensures that we won't trip up when access checking tests the
2789 * BYREF return value.
2790 */
2791 strsz = dtrace_strlen((char *)addr, size) + 1;
2792
2793 if (mstate->dtms_scratch_ptr + strsz >
2794 mstate->dtms_scratch_base + mstate->dtms_scratch_size) {
2795 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
2796 return (NULL);
2797 }
2798
2799 dtrace_strcpy((const void *)addr, (void *)mstate->dtms_scratch_ptr,
2800 strsz);
2801 ret = mstate->dtms_scratch_ptr;
2802 mstate->dtms_scratch_ptr += strsz;
2803 return (ret);
2804 }
2805
2806 /*
2807 * This function implements the DIF emulator's variable lookups. The emulator
2808 * passes a reserved variable identifier and optional built-in array index.
2809 */
2810 static uint64_t
2811 dtrace_dif_variable(dtrace_mstate_t *mstate, dtrace_state_t *state, uint64_t v,
2812 uint64_t ndx)
2813 {
2814 /*
2815 * If we're accessing one of the uncached arguments, we'll turn this
2816 * into a reference in the args array.
2817 */
2818 if (v >= DIF_VAR_ARG0 && v <= DIF_VAR_ARG9) {
2819 ndx = v - DIF_VAR_ARG0;
2820 v = DIF_VAR_ARGS;
2821 }
2822
2823 switch (v) {
2824 case DIF_VAR_ARGS:
2825 if (!(mstate->dtms_access & DTRACE_ACCESS_ARGS)) {
2826 cpu_core[CPU->cpu_id].cpuc_dtrace_flags |=
2827 CPU_DTRACE_KPRIV;
2828 return (0);
2829 }
2830
2831 ASSERT(mstate->dtms_present & DTRACE_MSTATE_ARGS);
2832 if (ndx >= sizeof (mstate->dtms_arg) /
2833 sizeof (mstate->dtms_arg[0])) {
2834 int aframes = mstate->dtms_probe->dtpr_aframes + 2;
2835 dtrace_provider_t *pv;
2836 uint64_t val;
2837
2838 pv = mstate->dtms_probe->dtpr_provider;
2839 if (pv->dtpv_pops.dtps_getargval != NULL)
2840 val = pv->dtpv_pops.dtps_getargval(pv->dtpv_arg,
2841 mstate->dtms_probe->dtpr_id,
2842 mstate->dtms_probe->dtpr_arg, ndx, aframes);
2843 else
2844 val = dtrace_getarg(ndx, aframes);
2845
2846 /*
2847 * This is regrettably required to keep the compiler
2848 * from tail-optimizing the call to dtrace_getarg().
2849 * The condition always evaluates to true, but the
2850 * compiler has no way of figuring that out a priori.
2851 * (None of this would be necessary if the compiler
2852 * could be relied upon to _always_ tail-optimize
2853 * the call to dtrace_getarg() -- but it can't.)
2854 */
2855 if (mstate->dtms_probe != NULL)
2856 return (val);
2857
2858 ASSERT(0);
2859 }
2860
2861 return (mstate->dtms_arg[ndx]);
2862
2863 case DIF_VAR_UREGS: {
2864 klwp_t *lwp;
2865
2866 if (!dtrace_priv_proc(state, mstate))
2867 return (0);
2868
2869 if ((lwp = curthread->t_lwp) == NULL) {
2870 DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR);
2871 cpu_core[CPU->cpu_id].cpuc_dtrace_illval = NULL;
2872 return (0);
2873 }
2874
2875 return (dtrace_getreg(lwp->lwp_regs, ndx));
2876 }
2877
2878 case DIF_VAR_VMREGS: {
2879 uint64_t rval;
2880
2881 if (!dtrace_priv_kernel(state))
2882 return (0);
2883
2884 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
2885
2886 rval = dtrace_getvmreg(ndx,
2887 &cpu_core[CPU->cpu_id].cpuc_dtrace_flags);
2888
2889 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
2890
2891 return (rval);
2892 }
2893
2894 case DIF_VAR_CURTHREAD:
2895 if (!dtrace_priv_kernel(state))
2896 return (0);
2897 return ((uint64_t)(uintptr_t)curthread);
2898
2899 case DIF_VAR_TIMESTAMP:
2900 if (!(mstate->dtms_present & DTRACE_MSTATE_TIMESTAMP)) {
2901 mstate->dtms_timestamp = dtrace_gethrtime();
2902 mstate->dtms_present |= DTRACE_MSTATE_TIMESTAMP;
2903 }
2904 return (mstate->dtms_timestamp);
2905
2906 case DIF_VAR_VTIMESTAMP:
2907 ASSERT(dtrace_vtime_references != 0);
2908 return (curthread->t_dtrace_vtime);
2909
2910 case DIF_VAR_WALLTIMESTAMP:
2911 if (!(mstate->dtms_present & DTRACE_MSTATE_WALLTIMESTAMP)) {
2912 mstate->dtms_walltimestamp = dtrace_gethrestime();
2913 mstate->dtms_present |= DTRACE_MSTATE_WALLTIMESTAMP;
2914 }
2915 return (mstate->dtms_walltimestamp);
2916
2917 case DIF_VAR_IPL:
2918 if (!dtrace_priv_kernel(state))
2919 return (0);
2920 if (!(mstate->dtms_present & DTRACE_MSTATE_IPL)) {
2921 mstate->dtms_ipl = dtrace_getipl();
2922 mstate->dtms_present |= DTRACE_MSTATE_IPL;
2923 }
2924 return (mstate->dtms_ipl);
2925
2926 case DIF_VAR_EPID:
2927 ASSERT(mstate->dtms_present & DTRACE_MSTATE_EPID);
2928 return (mstate->dtms_epid);
2929
2930 case DIF_VAR_ID:
2931 ASSERT(mstate->dtms_present & DTRACE_MSTATE_PROBE);
2932 return (mstate->dtms_probe->dtpr_id);
2933
2934 case DIF_VAR_STACKDEPTH:
2935 if (!dtrace_priv_kernel(state))
2936 return (0);
2937 if (!(mstate->dtms_present & DTRACE_MSTATE_STACKDEPTH)) {
2938 int aframes = mstate->dtms_probe->dtpr_aframes + 2;
2939
2940 mstate->dtms_stackdepth = dtrace_getstackdepth(aframes);
2941 mstate->dtms_present |= DTRACE_MSTATE_STACKDEPTH;
2942 }
2943 return (mstate->dtms_stackdepth);
2944
2945 case DIF_VAR_USTACKDEPTH:
2946 if (!dtrace_priv_proc(state, mstate))
2947 return (0);
2948 if (!(mstate->dtms_present & DTRACE_MSTATE_USTACKDEPTH)) {
2949 /*
2950 * See comment in DIF_VAR_PID.
2951 */
2952 if (DTRACE_ANCHORED(mstate->dtms_probe) &&
2953 CPU_ON_INTR(CPU)) {
2954 mstate->dtms_ustackdepth = 0;
2955 } else {
2956 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
2957 mstate->dtms_ustackdepth =
2958 dtrace_getustackdepth();
2959 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
2960 }
2961 mstate->dtms_present |= DTRACE_MSTATE_USTACKDEPTH;
2962 }
2963 return (mstate->dtms_ustackdepth);
2964
2965 case DIF_VAR_CALLER:
2966 if (!dtrace_priv_kernel(state))
2967 return (0);
2968 if (!(mstate->dtms_present & DTRACE_MSTATE_CALLER)) {
2969 int aframes = mstate->dtms_probe->dtpr_aframes + 2;
2970
2971 if (!DTRACE_ANCHORED(mstate->dtms_probe)) {
2972 /*
2973 * If this is an unanchored probe, we are
2974 * required to go through the slow path:
2975 * dtrace_caller() only guarantees correct
2976 * results for anchored probes.
2977 */
2978 pc_t caller[2];
2979
2980 dtrace_getpcstack(caller, 2, aframes,
2981 (uint32_t *)(uintptr_t)mstate->dtms_arg[0]);
2982 mstate->dtms_caller = caller[1];
2983 } else if ((mstate->dtms_caller =
2984 dtrace_caller(aframes)) == -1) {
2985 /*
2986 * We have failed to do this the quick way;
2987 * we must resort to the slower approach of
2988 * calling dtrace_getpcstack().
2989 */
2990 pc_t caller;
2991
2992 dtrace_getpcstack(&caller, 1, aframes, NULL);
2993 mstate->dtms_caller = caller;
2994 }
2995
2996 mstate->dtms_present |= DTRACE_MSTATE_CALLER;
2997 }
2998 return (mstate->dtms_caller);
2999
3000 case DIF_VAR_UCALLER:
3001 if (!dtrace_priv_proc(state, mstate))
3002 return (0);
3003
3004 if (!(mstate->dtms_present & DTRACE_MSTATE_UCALLER)) {
3005 uint64_t ustack[3];
3006
3007 /*
3008 * dtrace_getupcstack() fills in the first uint64_t
3009 * with the current PID. The second uint64_t will
3010 * be the program counter at user-level. The third
3011 * uint64_t will contain the caller, which is what
3012 * we're after.
3013 */
3014 ustack[2] = NULL;
3015 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
3016 dtrace_getupcstack(ustack, 3);
3017 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
3018 mstate->dtms_ucaller = ustack[2];
3019 mstate->dtms_present |= DTRACE_MSTATE_UCALLER;
3020 }
3021
3022 return (mstate->dtms_ucaller);
3023
3024 case DIF_VAR_PROBEPROV:
3025 ASSERT(mstate->dtms_present & DTRACE_MSTATE_PROBE);
3026 return (dtrace_dif_varstr(
3027 (uintptr_t)mstate->dtms_probe->dtpr_provider->dtpv_name,
3028 state, mstate));
3029
3030 case DIF_VAR_PROBEMOD:
3031 ASSERT(mstate->dtms_present & DTRACE_MSTATE_PROBE);
3032 return (dtrace_dif_varstr(
3033 (uintptr_t)mstate->dtms_probe->dtpr_mod,
3034 state, mstate));
3035
3036 case DIF_VAR_PROBEFUNC:
3037 ASSERT(mstate->dtms_present & DTRACE_MSTATE_PROBE);
3038 return (dtrace_dif_varstr(
3039 (uintptr_t)mstate->dtms_probe->dtpr_func,
3040 state, mstate));
3041
3042 case DIF_VAR_PROBENAME:
3043 ASSERT(mstate->dtms_present & DTRACE_MSTATE_PROBE);
3044 return (dtrace_dif_varstr(
3045 (uintptr_t)mstate->dtms_probe->dtpr_name,
3046 state, mstate));
3047
3048 case DIF_VAR_PID:
3049 if (!dtrace_priv_proc(state, mstate))
3050 return (0);
3051
3052 /*
3053 * Note that we are assuming that an unanchored probe is
3054 * always due to a high-level interrupt. (And we're assuming
3055 * that there is only a single high level interrupt.)
3056 */
3057 if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU))
3058 return (pid0.pid_id);
3059
3060 /*
3061 * It is always safe to dereference one's own t_procp pointer:
3062 * it always points to a valid, allocated proc structure.
3063 * Further, it is always safe to dereference the p_pidp member
3064 * of one's own proc structure. (These are truisms becuase
3065 * threads and processes don't clean up their own state --
3066 * they leave that task to whomever reaps them.)
3067 */
3068 return ((uint64_t)curthread->t_procp->p_pidp->pid_id);
3069
3070 case DIF_VAR_PPID:
3071 if (!dtrace_priv_proc(state, mstate))
3072 return (0);
3073
3074 /*
3075 * See comment in DIF_VAR_PID.
3076 */
3077 if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU))
3078 return (pid0.pid_id);
3079
3080 /*
3081 * It is always safe to dereference one's own t_procp pointer:
3082 * it always points to a valid, allocated proc structure.
3083 * (This is true because threads don't clean up their own
3084 * state -- they leave that task to whomever reaps them.)
3085 */
3086 return ((uint64_t)curthread->t_procp->p_ppid);
3087
3088 case DIF_VAR_TID:
3089 /*
3090 * See comment in DIF_VAR_PID.
3091 */
3092 if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU))
3093 return (0);
3094
3095 return ((uint64_t)curthread->t_tid);
3096
3097 case DIF_VAR_EXECNAME:
3098 if (!dtrace_priv_proc(state, mstate))
3099 return (0);
3100
3101 /*
3102 * See comment in DIF_VAR_PID.
3103 */
3104 if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU))
3105 return ((uint64_t)(uintptr_t)p0.p_user.u_comm);
3106
3107 /*
3108 * It is always safe to dereference one's own t_procp pointer:
3109 * it always points to a valid, allocated proc structure.
3110 * (This is true because threads don't clean up their own
3111 * state -- they leave that task to whomever reaps them.)
3112 */
3113 return (dtrace_dif_varstr(
3114 (uintptr_t)curthread->t_procp->p_user.u_comm,
3115 state, mstate));
3116
3117 case DIF_VAR_ZONENAME:
3118 if (!dtrace_priv_proc(state, mstate))
3119 return (0);
3120
3121 /*
3122 * See comment in DIF_VAR_PID.
3123 */
3124 if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU))
3125 return ((uint64_t)(uintptr_t)p0.p_zone->zone_name);
3126
3127 /*
3128 * It is always safe to dereference one's own t_procp pointer:
3129 * it always points to a valid, allocated proc structure.
3130 * (This is true because threads don't clean up their own
3131 * state -- they leave that task to whomever reaps them.)
3132 */
3133 return (dtrace_dif_varstr(
3134 (uintptr_t)curthread->t_procp->p_zone->zone_name,
3135 state, mstate));
3136
3137 case DIF_VAR_UID:
3138 if (!dtrace_priv_proc(state, mstate))
3139 return (0);
3140
3141 /*
3142 * See comment in DIF_VAR_PID.
3143 */
3144 if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU))
3145 return ((uint64_t)p0.p_cred->cr_uid);
3146
3147 /*
3148 * It is always safe to dereference one's own t_procp pointer:
3149 * it always points to a valid, allocated proc structure.
3150 * (This is true because threads don't clean up their own
3151 * state -- they leave that task to whomever reaps them.)
3152 *
3153 * Additionally, it is safe to dereference one's own process
3154 * credential, since this is never NULL after process birth.
3155 */
3156 return ((uint64_t)curthread->t_procp->p_cred->cr_uid);
3157
3158 case DIF_VAR_GID:
3159 if (!dtrace_priv_proc(state, mstate))
3160 return (0);
3161
3162 /*
3163 * See comment in DIF_VAR_PID.
3164 */
3165 if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU))
3166 return ((uint64_t)p0.p_cred->cr_gid);
3167
3168 /*
3169 * It is always safe to dereference one's own t_procp pointer:
3170 * it always points to a valid, allocated proc structure.
3171 * (This is true because threads don't clean up their own
3172 * state -- they leave that task to whomever reaps them.)
3173 *
3174 * Additionally, it is safe to dereference one's own process
3175 * credential, since this is never NULL after process birth.
3176 */
3177 return ((uint64_t)curthread->t_procp->p_cred->cr_gid);
3178
3179 case DIF_VAR_ERRNO: {
3180 klwp_t *lwp;
3181 if (!dtrace_priv_proc(state, mstate))
3182 return (0);
3183
3184 /*
3185 * See comment in DIF_VAR_PID.
3186 */
3187 if (DTRACE_ANCHORED(mstate->dtms_probe) && CPU_ON_INTR(CPU))
3188 return (0);
3189
3190 /*
3191 * It is always safe to dereference one's own t_lwp pointer in
3192 * the event that this pointer is non-NULL. (This is true
3193 * because threads and lwps don't clean up their own state --
3194 * they leave that task to whomever reaps them.)
3195 */
3196 if ((lwp = curthread->t_lwp) == NULL)
3197 return (0);
3198
3199 return ((uint64_t)lwp->lwp_errno);
3200 }
3201 default:
3202 DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP);
3203 return (0);
3204 }
3205 }
3206
3207 /*
3208 * Emulate the execution of DTrace ID subroutines invoked by the call opcode.
3209 * Notice that we don't bother validating the proper number of arguments or
3210 * their types in the tuple stack. This isn't needed because all argument
3211 * interpretation is safe because of our load safety -- the worst that can
3212 * happen is that a bogus program can obtain bogus results.
3213 */
3214 static void
3215 dtrace_dif_subr(uint_t subr, uint_t rd, uint64_t *regs,
3216 dtrace_key_t *tupregs, int nargs,
3217 dtrace_mstate_t *mstate, dtrace_state_t *state)
3218 {
3219 volatile uint16_t *flags = &cpu_core[CPU->cpu_id].cpuc_dtrace_flags;
3220 volatile uintptr_t *illval = &cpu_core[CPU->cpu_id].cpuc_dtrace_illval;
3221 dtrace_vstate_t *vstate = &state->dts_vstate;
3222
3223 union {
3224 mutex_impl_t mi;
3225 uint64_t mx;
3226 } m;
3227
3228 union {
3229 krwlock_t ri;
3230 uintptr_t rw;
3231 } r;
3232
3233 switch (subr) {
3234 case DIF_SUBR_RAND:
3235 regs[rd] = (dtrace_gethrtime() * 2416 + 374441) % 1771875;
3236 break;
3237
3238 case DIF_SUBR_MUTEX_OWNED:
3239 if (!dtrace_canload(tupregs[0].dttk_value, sizeof (kmutex_t),
3240 mstate, vstate)) {
3241 regs[rd] = NULL;
3242 break;
3243 }
3244
3245 m.mx = dtrace_load64(tupregs[0].dttk_value);
3246 if (MUTEX_TYPE_ADAPTIVE(&m.mi))
3247 regs[rd] = MUTEX_OWNER(&m.mi) != MUTEX_NO_OWNER;
3248 else
3249 regs[rd] = LOCK_HELD(&m.mi.m_spin.m_spinlock);
3250 break;
3251
3252 case DIF_SUBR_MUTEX_OWNER:
3253 if (!dtrace_canload(tupregs[0].dttk_value, sizeof (kmutex_t),
3254 mstate, vstate)) {
3255 regs[rd] = NULL;
3256 break;
3257 }
3258
3259 m.mx = dtrace_load64(tupregs[0].dttk_value);
3260 if (MUTEX_TYPE_ADAPTIVE(&m.mi) &&
3261 MUTEX_OWNER(&m.mi) != MUTEX_NO_OWNER)
3262 regs[rd] = (uintptr_t)MUTEX_OWNER(&m.mi);
3263 else
3264 regs[rd] = 0;
3265 break;
3266
3267 case DIF_SUBR_MUTEX_TYPE_ADAPTIVE:
3268 if (!dtrace_canload(tupregs[0].dttk_value, sizeof (kmutex_t),
3269 mstate, vstate)) {
3270 regs[rd] = NULL;
3271 break;
3272 }
3273
3274 m.mx = dtrace_load64(tupregs[0].dttk_value);
3275 regs[rd] = MUTEX_TYPE_ADAPTIVE(&m.mi);
3276 break;
3277
3278 case DIF_SUBR_MUTEX_TYPE_SPIN:
3279 if (!dtrace_canload(tupregs[0].dttk_value, sizeof (kmutex_t),
3280 mstate, vstate)) {
3281 regs[rd] = NULL;
3282 break;
3283 }
3284
3285 m.mx = dtrace_load64(tupregs[0].dttk_value);
3286 regs[rd] = MUTEX_TYPE_SPIN(&m.mi);
3287 break;
3288
3289 case DIF_SUBR_RW_READ_HELD: {
3290 uintptr_t tmp;
3291
3292 if (!dtrace_canload(tupregs[0].dttk_value, sizeof (uintptr_t),
3293 mstate, vstate)) {
3294 regs[rd] = NULL;
3295 break;
3296 }
3297
3298 r.rw = dtrace_loadptr(tupregs[0].dttk_value);
3299 regs[rd] = _RW_READ_HELD(&r.ri, tmp);
3300 break;
3301 }
3302
3303 case DIF_SUBR_RW_WRITE_HELD:
3304 if (!dtrace_canload(tupregs[0].dttk_value, sizeof (krwlock_t),
3305 mstate, vstate)) {
3306 regs[rd] = NULL;
3307 break;
3308 }
3309
3310 r.rw = dtrace_loadptr(tupregs[0].dttk_value);
3311 regs[rd] = _RW_WRITE_HELD(&r.ri);
3312 break;
3313
3314 case DIF_SUBR_RW_ISWRITER:
3315 if (!dtrace_canload(tupregs[0].dttk_value, sizeof (krwlock_t),
3316 mstate, vstate)) {
3317 regs[rd] = NULL;
3318 break;
3319 }
3320
3321 r.rw = dtrace_loadptr(tupregs[0].dttk_value);
3322 regs[rd] = _RW_ISWRITER(&r.ri);
3323 break;
3324
3325 case DIF_SUBR_BCOPY: {
3326 /*
3327 * We need to be sure that the destination is in the scratch
3328 * region -- no other region is allowed.
3329 */
3330 uintptr_t src = tupregs[0].dttk_value;
3331 uintptr_t dest = tupregs[1].dttk_value;
3332 size_t size = tupregs[2].dttk_value;
3333
3334 if (!dtrace_inscratch(dest, size, mstate)) {
3335 *flags |= CPU_DTRACE_BADADDR;
3336 *illval = regs[rd];
3337 break;
3338 }
3339
3340 if (!dtrace_canload(src, size, mstate, vstate)) {
3341 regs[rd] = NULL;
3342 break;
3343 }
3344
3345 dtrace_bcopy((void *)src, (void *)dest, size);
3346 break;
3347 }
3348
3349 case DIF_SUBR_ALLOCA:
3350 case DIF_SUBR_COPYIN: {
3351 uintptr_t dest = P2ROUNDUP(mstate->dtms_scratch_ptr, 8);
3352 uint64_t size =
3353 tupregs[subr == DIF_SUBR_ALLOCA ? 0 : 1].dttk_value;
3354 size_t scratch_size = (dest - mstate->dtms_scratch_ptr) + size;
3355
3356 /*
3357 * This action doesn't require any credential checks since
3358 * probes will not activate in user contexts to which the
3359 * enabling user does not have permissions.
3360 */
3361
3362 /*
3363 * Rounding up the user allocation size could have overflowed
3364 * a large, bogus allocation (like -1ULL) to 0.
3365 */
3366 if (scratch_size < size ||
3367 !DTRACE_INSCRATCH(mstate, scratch_size)) {
3368 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
3369 regs[rd] = NULL;
3370 break;
3371 }
3372
3373 if (subr == DIF_SUBR_COPYIN) {
3374 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
3375 dtrace_copyin(tupregs[0].dttk_value, dest, size, flags);
3376 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
3377 }
3378
3379 mstate->dtms_scratch_ptr += scratch_size;
3380 regs[rd] = dest;
3381 break;
3382 }
3383
3384 case DIF_SUBR_COPYINTO: {
3385 uint64_t size = tupregs[1].dttk_value;
3386 uintptr_t dest = tupregs[2].dttk_value;
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 if (!dtrace_inscratch(dest, size, mstate)) {
3394 *flags |= CPU_DTRACE_BADADDR;
3395 *illval = regs[rd];
3396 break;
3397 }
3398
3399 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
3400 dtrace_copyin(tupregs[0].dttk_value, dest, size, flags);
3401 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
3402 break;
3403 }
3404
3405 case DIF_SUBR_COPYINSTR: {
3406 uintptr_t dest = mstate->dtms_scratch_ptr;
3407 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
3408
3409 if (nargs > 1 && tupregs[1].dttk_value < size)
3410 size = tupregs[1].dttk_value + 1;
3411
3412 /*
3413 * This action doesn't require any credential checks since
3414 * probes will not activate in user contexts to which the
3415 * enabling user does not have permissions.
3416 */
3417 if (!DTRACE_INSCRATCH(mstate, size)) {
3418 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
3419 regs[rd] = NULL;
3420 break;
3421 }
3422
3423 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
3424 dtrace_copyinstr(tupregs[0].dttk_value, dest, size, flags);
3425 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
3426
3427 ((char *)dest)[size - 1] = '\0';
3428 mstate->dtms_scratch_ptr += size;
3429 regs[rd] = dest;
3430 break;
3431 }
3432
3433 case DIF_SUBR_MSGSIZE:
3434 case DIF_SUBR_MSGDSIZE: {
3435 uintptr_t baddr = tupregs[0].dttk_value, daddr;
3436 uintptr_t wptr, rptr;
3437 size_t count = 0;
3438 int cont = 0;
3439
3440 while (baddr != NULL && !(*flags & CPU_DTRACE_FAULT)) {
3441
3442 if (!dtrace_canload(baddr, sizeof (mblk_t), mstate,
3443 vstate)) {
3444 regs[rd] = NULL;
3445 break;
3446 }
3447
3448 wptr = dtrace_loadptr(baddr +
3449 offsetof(mblk_t, b_wptr));
3450
3451 rptr = dtrace_loadptr(baddr +
3452 offsetof(mblk_t, b_rptr));
3453
3454 if (wptr < rptr) {
3455 *flags |= CPU_DTRACE_BADADDR;
3456 *illval = tupregs[0].dttk_value;
3457 break;
3458 }
3459
3460 daddr = dtrace_loadptr(baddr +
3461 offsetof(mblk_t, b_datap));
3462
3463 baddr = dtrace_loadptr(baddr +
3464 offsetof(mblk_t, b_cont));
3465
3466 /*
3467 * We want to prevent against denial-of-service here,
3468 * so we're only going to search the list for
3469 * dtrace_msgdsize_max mblks.
3470 */
3471 if (cont++ > dtrace_msgdsize_max) {
3472 *flags |= CPU_DTRACE_ILLOP;
3473 break;
3474 }
3475
3476 if (subr == DIF_SUBR_MSGDSIZE) {
3477 if (dtrace_load8(daddr +
3478 offsetof(dblk_t, db_type)) != M_DATA)
3479 continue;
3480 }
3481
3482 count += wptr - rptr;
3483 }
3484
3485 if (!(*flags & CPU_DTRACE_FAULT))
3486 regs[rd] = count;
3487
3488 break;
3489 }
3490
3491 case DIF_SUBR_PROGENYOF: {
3492 pid_t pid = tupregs[0].dttk_value;
3493 proc_t *p;
3494 int rval = 0;
3495
3496 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
3497
3498 for (p = curthread->t_procp; p != NULL; p = p->p_parent) {
3499 if (p->p_pidp->pid_id == pid) {
3500 rval = 1;
3501 break;
3502 }
3503 }
3504
3505 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
3506
3507 regs[rd] = rval;
3508 break;
3509 }
3510
3511 case DIF_SUBR_SPECULATION:
3512 regs[rd] = dtrace_speculation(state);
3513 break;
3514
3515 case DIF_SUBR_COPYOUT: {
3516 uintptr_t kaddr = tupregs[0].dttk_value;
3517 uintptr_t uaddr = tupregs[1].dttk_value;
3518 uint64_t size = tupregs[2].dttk_value;
3519
3520 if (!dtrace_destructive_disallow &&
3521 dtrace_priv_proc_control(state, mstate) &&
3522 !dtrace_istoxic(kaddr, size)) {
3523 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
3524 dtrace_copyout(kaddr, uaddr, size, flags);
3525 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
3526 }
3527 break;
3528 }
3529
3530 case DIF_SUBR_COPYOUTSTR: {
3531 uintptr_t kaddr = tupregs[0].dttk_value;
3532 uintptr_t uaddr = tupregs[1].dttk_value;
3533 uint64_t size = tupregs[2].dttk_value;
3534
3535 if (!dtrace_destructive_disallow &&
3536 dtrace_priv_proc_control(state, mstate) &&
3537 !dtrace_istoxic(kaddr, size)) {
3538 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
3539 dtrace_copyoutstr(kaddr, uaddr, size, flags);
3540 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
3541 }
3542 break;
3543 }
3544
3545 case DIF_SUBR_STRLEN: {
3546 size_t sz;
3547 uintptr_t addr = (uintptr_t)tupregs[0].dttk_value;
3548 sz = dtrace_strlen((char *)addr,
3549 state->dts_options[DTRACEOPT_STRSIZE]);
3550
3551 if (!dtrace_canload(addr, sz + 1, mstate, vstate)) {
3552 regs[rd] = NULL;
3553 break;
3554 }
3555
3556 regs[rd] = sz;
3557
3558 break;
3559 }
3560
3561 case DIF_SUBR_STRCHR:
3562 case DIF_SUBR_STRRCHR: {
3563 /*
3564 * We're going to iterate over the string looking for the
3565 * specified character. We will iterate until we have reached
3566 * the string length or we have found the character. If this
3567 * is DIF_SUBR_STRRCHR, we will look for the last occurrence
3568 * of the specified character instead of the first.
3569 */
3570 uintptr_t saddr = tupregs[0].dttk_value;
3571 uintptr_t addr = tupregs[0].dttk_value;
3572 uintptr_t limit = addr + state->dts_options[DTRACEOPT_STRSIZE];
3573 char c, target = (char)tupregs[1].dttk_value;
3574
3575 for (regs[rd] = NULL; addr < limit; addr++) {
3576 if ((c = dtrace_load8(addr)) == target) {
3577 regs[rd] = addr;
3578
3579 if (subr == DIF_SUBR_STRCHR)
3580 break;
3581 }
3582
3583 if (c == '\0')
3584 break;
3585 }
3586
3587 if (!dtrace_canload(saddr, addr - saddr, mstate, vstate)) {
3588 regs[rd] = NULL;
3589 break;
3590 }
3591
3592 break;
3593 }
3594
3595 case DIF_SUBR_STRSTR:
3596 case DIF_SUBR_INDEX:
3597 case DIF_SUBR_RINDEX: {
3598 /*
3599 * We're going to iterate over the string looking for the
3600 * specified string. We will iterate until we have reached
3601 * the string length or we have found the string. (Yes, this
3602 * is done in the most naive way possible -- but considering
3603 * that the string we're searching for is likely to be
3604 * relatively short, the complexity of Rabin-Karp or similar
3605 * hardly seems merited.)
3606 */
3607 char *addr = (char *)(uintptr_t)tupregs[0].dttk_value;
3608 char *substr = (char *)(uintptr_t)tupregs[1].dttk_value;
3609 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
3610 size_t len = dtrace_strlen(addr, size);
3611 size_t sublen = dtrace_strlen(substr, size);
3612 char *limit = addr + len, *orig = addr;
3613 int notfound = subr == DIF_SUBR_STRSTR ? 0 : -1;
3614 int inc = 1;
3615
3616 regs[rd] = notfound;
3617
3618 if (!dtrace_canload((uintptr_t)addr, len + 1, mstate, vstate)) {
3619 regs[rd] = NULL;
3620 break;
3621 }
3622
3623 if (!dtrace_canload((uintptr_t)substr, sublen + 1, mstate,
3624 vstate)) {
3625 regs[rd] = NULL;
3626 break;
3627 }
3628
3629 /*
3630 * strstr() and index()/rindex() have similar semantics if
3631 * both strings are the empty string: strstr() returns a
3632 * pointer to the (empty) string, and index() and rindex()
3633 * both return index 0 (regardless of any position argument).
3634 */
3635 if (sublen == 0 && len == 0) {
3636 if (subr == DIF_SUBR_STRSTR)
3637 regs[rd] = (uintptr_t)addr;
3638 else
3639 regs[rd] = 0;
3640 break;
3641 }
3642
3643 if (subr != DIF_SUBR_STRSTR) {
3644 if (subr == DIF_SUBR_RINDEX) {
3645 limit = orig - 1;
3646 addr += len;
3647 inc = -1;
3648 }
3649
3650 /*
3651 * Both index() and rindex() take an optional position
3652 * argument that denotes the starting position.
3653 */
3654 if (nargs == 3) {
3655 int64_t pos = (int64_t)tupregs[2].dttk_value;
3656
3657 /*
3658 * If the position argument to index() is
3659 * negative, Perl implicitly clamps it at
3660 * zero. This semantic is a little surprising
3661 * given the special meaning of negative
3662 * positions to similar Perl functions like
3663 * substr(), but it appears to reflect a
3664 * notion that index() can start from a
3665 * negative index and increment its way up to
3666 * the string. Given this notion, Perl's
3667 * rindex() is at least self-consistent in
3668 * that it implicitly clamps positions greater
3669 * than the string length to be the string
3670 * length. Where Perl completely loses
3671 * coherence, however, is when the specified
3672 * substring is the empty string (""). In
3673 * this case, even if the position is
3674 * negative, rindex() returns 0 -- and even if
3675 * the position is greater than the length,
3676 * index() returns the string length. These
3677 * semantics violate the notion that index()
3678 * should never return a value less than the
3679 * specified position and that rindex() should
3680 * never return a value greater than the
3681 * specified position. (One assumes that
3682 * these semantics are artifacts of Perl's
3683 * implementation and not the results of
3684 * deliberate design -- it beggars belief that
3685 * even Larry Wall could desire such oddness.)
3686 * While in the abstract one would wish for
3687 * consistent position semantics across
3688 * substr(), index() and rindex() -- or at the
3689 * very least self-consistent position
3690 * semantics for index() and rindex() -- we
3691 * instead opt to keep with the extant Perl
3692 * semantics, in all their broken glory. (Do
3693 * we have more desire to maintain Perl's
3694 * semantics than Perl does? Probably.)
3695 */
3696 if (subr == DIF_SUBR_RINDEX) {
3697 if (pos < 0) {
3698 if (sublen == 0)
3699 regs[rd] = 0;
3700 break;
3701 }
3702
3703 if (pos > len)
3704 pos = len;
3705 } else {
3706 if (pos < 0)
3707 pos = 0;
3708
3709 if (pos >= len) {
3710 if (sublen == 0)
3711 regs[rd] = len;
3712 break;
3713 }
3714 }
3715
3716 addr = orig + pos;
3717 }
3718 }
3719
3720 for (regs[rd] = notfound; addr != limit; addr += inc) {
3721 if (dtrace_strncmp(addr, substr, sublen) == 0) {
3722 if (subr != DIF_SUBR_STRSTR) {
3723 /*
3724 * As D index() and rindex() are
3725 * modeled on Perl (and not on awk),
3726 * we return a zero-based (and not a
3727 * one-based) index. (For you Perl
3728 * weenies: no, we're not going to add
3729 * $[ -- and shouldn't you be at a con
3730 * or something?)
3731 */
3732 regs[rd] = (uintptr_t)(addr - orig);
3733 break;
3734 }
3735
3736 ASSERT(subr == DIF_SUBR_STRSTR);
3737 regs[rd] = (uintptr_t)addr;
3738 break;
3739 }
3740 }
3741
3742 break;
3743 }
3744
3745 case DIF_SUBR_STRTOK: {
3746 uintptr_t addr = tupregs[0].dttk_value;
3747 uintptr_t tokaddr = tupregs[1].dttk_value;
3748 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
3749 uintptr_t limit, toklimit = tokaddr + size;
3750 uint8_t c, tokmap[32]; /* 256 / 8 */
3751 char *dest = (char *)mstate->dtms_scratch_ptr;
3752 int i;
3753
3754 /*
3755 * Check both the token buffer and (later) the input buffer,
3756 * since both could be non-scratch addresses.
3757 */
3758 if (!dtrace_strcanload(tokaddr, size, mstate, vstate)) {
3759 regs[rd] = NULL;
3760 break;
3761 }
3762
3763 if (!DTRACE_INSCRATCH(mstate, size)) {
3764 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
3765 regs[rd] = NULL;
3766 break;
3767 }
3768
3769 if (addr == NULL) {
3770 /*
3771 * If the address specified is NULL, we use our saved
3772 * strtok pointer from the mstate. Note that this
3773 * means that the saved strtok pointer is _only_
3774 * valid within multiple enablings of the same probe --
3775 * it behaves like an implicit clause-local variable.
3776 */
3777 addr = mstate->dtms_strtok;
3778 } else {
3779 /*
3780 * If the user-specified address is non-NULL we must
3781 * access check it. This is the only time we have
3782 * a chance to do so, since this address may reside
3783 * in the string table of this clause-- future calls
3784 * (when we fetch addr from mstate->dtms_strtok)
3785 * would fail this access check.
3786 */
3787 if (!dtrace_strcanload(addr, size, mstate, vstate)) {
3788 regs[rd] = NULL;
3789 break;
3790 }
3791 }
3792
3793 /*
3794 * First, zero the token map, and then process the token
3795 * string -- setting a bit in the map for every character
3796 * found in the token string.
3797 */
3798 for (i = 0; i < sizeof (tokmap); i++)
3799 tokmap[i] = 0;
3800
3801 for (; tokaddr < toklimit; tokaddr++) {
3802 if ((c = dtrace_load8(tokaddr)) == '\0')
3803 break;
3804
3805 ASSERT((c >> 3) < sizeof (tokmap));
3806 tokmap[c >> 3] |= (1 << (c & 0x7));
3807 }
3808
3809 for (limit = addr + size; addr < limit; addr++) {
3810 /*
3811 * We're looking for a character that is _not_ contained
3812 * in the token string.
3813 */
3814 if ((c = dtrace_load8(addr)) == '\0')
3815 break;
3816
3817 if (!(tokmap[c >> 3] & (1 << (c & 0x7))))
3818 break;
3819 }
3820
3821 if (c == '\0') {
3822 /*
3823 * We reached the end of the string without finding
3824 * any character that was not in the token string.
3825 * We return NULL in this case, and we set the saved
3826 * address to NULL as well.
3827 */
3828 regs[rd] = NULL;
3829 mstate->dtms_strtok = NULL;
3830 break;
3831 }
3832
3833 /*
3834 * From here on, we're copying into the destination string.
3835 */
3836 for (i = 0; addr < limit && i < size - 1; addr++) {
3837 if ((c = dtrace_load8(addr)) == '\0')
3838 break;
3839
3840 if (tokmap[c >> 3] & (1 << (c & 0x7)))
3841 break;
3842
3843 ASSERT(i < size);
3844 dest[i++] = c;
3845 }
3846
3847 ASSERT(i < size);
3848 dest[i] = '\0';
3849 regs[rd] = (uintptr_t)dest;
3850 mstate->dtms_scratch_ptr += size;
3851 mstate->dtms_strtok = addr;
3852 break;
3853 }
3854
3855 case DIF_SUBR_SUBSTR: {
3856 uintptr_t s = tupregs[0].dttk_value;
3857 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
3858 char *d = (char *)mstate->dtms_scratch_ptr;
3859 int64_t index = (int64_t)tupregs[1].dttk_value;
3860 int64_t remaining = (int64_t)tupregs[2].dttk_value;
3861 size_t len = dtrace_strlen((char *)s, size);
3862 int64_t i;
3863
3864 if (!dtrace_canload(s, len + 1, mstate, vstate)) {
3865 regs[rd] = NULL;
3866 break;
3867 }
3868
3869 if (!DTRACE_INSCRATCH(mstate, size)) {
3870 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
3871 regs[rd] = NULL;
3872 break;
3873 }
3874
3875 if (nargs <= 2)
3876 remaining = (int64_t)size;
3877
3878 if (index < 0) {
3879 index += len;
3880
3881 if (index < 0 && index + remaining > 0) {
3882 remaining += index;
3883 index = 0;
3884 }
3885 }
3886
3887 if (index >= len || index < 0) {
3888 remaining = 0;
3889 } else if (remaining < 0) {
3890 remaining += len - index;
3891 } else if (index + remaining > size) {
3892 remaining = size - index;
3893 }
3894
3895 for (i = 0; i < remaining; i++) {
3896 if ((d[i] = dtrace_load8(s + index + i)) == '\0')
3897 break;
3898 }
3899
3900 d[i] = '\0';
3901
3902 mstate->dtms_scratch_ptr += size;
3903 regs[rd] = (uintptr_t)d;
3904 break;
3905 }
3906
3907 case DIF_SUBR_TOUPPER:
3908 case DIF_SUBR_TOLOWER: {
3909 uintptr_t s = tupregs[0].dttk_value;
3910 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
3911 char *dest = (char *)mstate->dtms_scratch_ptr, c;
3912 size_t len = dtrace_strlen((char *)s, size);
3913 char lower, upper, convert;
3914 int64_t i;
3915
3916 if (subr == DIF_SUBR_TOUPPER) {
3917 lower = 'a';
3918 upper = 'z';
3919 convert = 'A';
3920 } else {
3921 lower = 'A';
3922 upper = 'Z';
3923 convert = 'a';
3924 }
3925
3926 if (!dtrace_canload(s, len + 1, mstate, vstate)) {
3927 regs[rd] = NULL;
3928 break;
3929 }
3930
3931 if (!DTRACE_INSCRATCH(mstate, size)) {
3932 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
3933 regs[rd] = NULL;
3934 break;
3935 }
3936
3937 for (i = 0; i < size - 1; i++) {
3938 if ((c = dtrace_load8(s + i)) == '\0')
3939 break;
3940
3941 if (c >= lower && c <= upper)
3942 c = convert + (c - lower);
3943
3944 dest[i] = c;
3945 }
3946
3947 ASSERT(i < size);
3948 dest[i] = '\0';
3949 regs[rd] = (uintptr_t)dest;
3950 mstate->dtms_scratch_ptr += size;
3951 break;
3952 }
3953
3954 case DIF_SUBR_GETMAJOR:
3955 #ifdef _LP64
3956 regs[rd] = (tupregs[0].dttk_value >> NBITSMINOR64) & MAXMAJ64;
3957 #else
3958 regs[rd] = (tupregs[0].dttk_value >> NBITSMINOR) & MAXMAJ;
3959 #endif
3960 break;
3961
3962 case DIF_SUBR_GETMINOR:
3963 #ifdef _LP64
3964 regs[rd] = tupregs[0].dttk_value & MAXMIN64;
3965 #else
3966 regs[rd] = tupregs[0].dttk_value & MAXMIN;
3967 #endif
3968 break;
3969
3970 case DIF_SUBR_DDI_PATHNAME: {
3971 /*
3972 * This one is a galactic mess. We are going to roughly
3973 * emulate ddi_pathname(), but it's made more complicated
3974 * by the fact that we (a) want to include the minor name and
3975 * (b) must proceed iteratively instead of recursively.
3976 */
3977 uintptr_t dest = mstate->dtms_scratch_ptr;
3978 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
3979 char *start = (char *)dest, *end = start + size - 1;
3980 uintptr_t daddr = tupregs[0].dttk_value;
3981 int64_t minor = (int64_t)tupregs[1].dttk_value;
3982 char *s;
3983 int i, len, depth = 0;
3984
3985 /*
3986 * Due to all the pointer jumping we do and context we must
3987 * rely upon, we just mandate that the user must have kernel
3988 * read privileges to use this routine.
3989 */
3990 if ((mstate->dtms_access & DTRACE_ACCESS_KERNEL) == 0) {
3991 *flags |= CPU_DTRACE_KPRIV;
3992 *illval = daddr;
3993 regs[rd] = NULL;
3994 }
3995
3996 if (!DTRACE_INSCRATCH(mstate, size)) {
3997 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
3998 regs[rd] = NULL;
3999 break;
4000 }
4001
4002 *end = '\0';
4003
4004 /*
4005 * We want to have a name for the minor. In order to do this,
4006 * we need to walk the minor list from the devinfo. We want
4007 * to be sure that we don't infinitely walk a circular list,
4008 * so we check for circularity by sending a scout pointer
4009 * ahead two elements for every element that we iterate over;
4010 * if the list is circular, these will ultimately point to the
4011 * same element. You may recognize this little trick as the
4012 * answer to a stupid interview question -- one that always
4013 * seems to be asked by those who had to have it laboriously
4014 * explained to them, and who can't even concisely describe
4015 * the conditions under which one would be forced to resort to
4016 * this technique. Needless to say, those conditions are
4017 * found here -- and probably only here. Is this the only use
4018 * of this infamous trick in shipping, production code? If it
4019 * isn't, it probably should be...
4020 */
4021 if (minor != -1) {
4022 uintptr_t maddr = dtrace_loadptr(daddr +
4023 offsetof(struct dev_info, devi_minor));
4024
4025 uintptr_t next = offsetof(struct ddi_minor_data, next);
4026 uintptr_t name = offsetof(struct ddi_minor_data,
4027 d_minor) + offsetof(struct ddi_minor, name);
4028 uintptr_t dev = offsetof(struct ddi_minor_data,
4029 d_minor) + offsetof(struct ddi_minor, dev);
4030 uintptr_t scout;
4031
4032 if (maddr != NULL)
4033 scout = dtrace_loadptr(maddr + next);
4034
4035 while (maddr != NULL && !(*flags & CPU_DTRACE_FAULT)) {
4036 uint64_t m;
4037 #ifdef _LP64
4038 m = dtrace_load64(maddr + dev) & MAXMIN64;
4039 #else
4040 m = dtrace_load32(maddr + dev) & MAXMIN;
4041 #endif
4042 if (m != minor) {
4043 maddr = dtrace_loadptr(maddr + next);
4044
4045 if (scout == NULL)
4046 continue;
4047
4048 scout = dtrace_loadptr(scout + next);
4049
4050 if (scout == NULL)
4051 continue;
4052
4053 scout = dtrace_loadptr(scout + next);
4054
4055 if (scout == NULL)
4056 continue;
4057
4058 if (scout == maddr) {
4059 *flags |= CPU_DTRACE_ILLOP;
4060 break;
4061 }
4062
4063 continue;
4064 }
4065
4066 /*
4067 * We have the minor data. Now we need to
4068 * copy the minor's name into the end of the
4069 * pathname.
4070 */
4071 s = (char *)dtrace_loadptr(maddr + name);
4072 len = dtrace_strlen(s, size);
4073
4074 if (*flags & CPU_DTRACE_FAULT)
4075 break;
4076
4077 if (len != 0) {
4078 if ((end -= (len + 1)) < start)
4079 break;
4080
4081 *end = ':';
4082 }
4083
4084 for (i = 1; i <= len; i++)
4085 end[i] = dtrace_load8((uintptr_t)s++);
4086 break;
4087 }
4088 }
4089
4090 while (daddr != NULL && !(*flags & CPU_DTRACE_FAULT)) {
4091 ddi_node_state_t devi_state;
4092
4093 devi_state = dtrace_load32(daddr +
4094 offsetof(struct dev_info, devi_node_state));
4095
4096 if (*flags & CPU_DTRACE_FAULT)
4097 break;
4098
4099 if (devi_state >= DS_INITIALIZED) {
4100 s = (char *)dtrace_loadptr(daddr +
4101 offsetof(struct dev_info, devi_addr));
4102 len = dtrace_strlen(s, size);
4103
4104 if (*flags & CPU_DTRACE_FAULT)
4105 break;
4106
4107 if (len != 0) {
4108 if ((end -= (len + 1)) < start)
4109 break;
4110
4111 *end = '@';
4112 }
4113
4114 for (i = 1; i <= len; i++)
4115 end[i] = dtrace_load8((uintptr_t)s++);
4116 }
4117
4118 /*
4119 * Now for the node name...
4120 */
4121 s = (char *)dtrace_loadptr(daddr +
4122 offsetof(struct dev_info, devi_node_name));
4123
4124 daddr = dtrace_loadptr(daddr +
4125 offsetof(struct dev_info, devi_parent));
4126
4127 /*
4128 * If our parent is NULL (that is, if we're the root
4129 * node), we're going to use the special path
4130 * "devices".
4131 */
4132 if (daddr == NULL)
4133 s = "devices";
4134
4135 len = dtrace_strlen(s, size);
4136 if (*flags & CPU_DTRACE_FAULT)
4137 break;
4138
4139 if ((end -= (len + 1)) < start)
4140 break;
4141
4142 for (i = 1; i <= len; i++)
4143 end[i] = dtrace_load8((uintptr_t)s++);
4144 *end = '/';
4145
4146 if (depth++ > dtrace_devdepth_max) {
4147 *flags |= CPU_DTRACE_ILLOP;
4148 break;
4149 }
4150 }
4151
4152 if (end < start)
4153 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
4154
4155 if (daddr == NULL) {
4156 regs[rd] = (uintptr_t)end;
4157 mstate->dtms_scratch_ptr += size;
4158 }
4159
4160 break;
4161 }
4162
4163 case DIF_SUBR_STRJOIN: {
4164 char *d = (char *)mstate->dtms_scratch_ptr;
4165 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
4166 uintptr_t s1 = tupregs[0].dttk_value;
4167 uintptr_t s2 = tupregs[1].dttk_value;
4168 int i = 0;
4169
4170 if (!dtrace_strcanload(s1, size, mstate, vstate) ||
4171 !dtrace_strcanload(s2, size, mstate, vstate)) {
4172 regs[rd] = NULL;
4173 break;
4174 }
4175
4176 if (!DTRACE_INSCRATCH(mstate, size)) {
4177 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
4178 regs[rd] = NULL;
4179 break;
4180 }
4181
4182 for (;;) {
4183 if (i >= size) {
4184 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
4185 regs[rd] = NULL;
4186 break;
4187 }
4188
4189 if ((d[i++] = dtrace_load8(s1++)) == '\0') {
4190 i--;
4191 break;
4192 }
4193 }
4194
4195 for (;;) {
4196 if (i >= size) {
4197 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
4198 regs[rd] = NULL;
4199 break;
4200 }
4201
4202 if ((d[i++] = dtrace_load8(s2++)) == '\0')
4203 break;
4204 }
4205
4206 if (i < size) {
4207 mstate->dtms_scratch_ptr += i;
4208 regs[rd] = (uintptr_t)d;
4209 }
4210
4211 break;
4212 }
4213
4214 case DIF_SUBR_LLTOSTR: {
4215 int64_t i = (int64_t)tupregs[0].dttk_value;
4216 uint64_t val, digit;
4217 uint64_t size = 65; /* enough room for 2^64 in binary */
4218 char *end = (char *)mstate->dtms_scratch_ptr + size - 1;
4219 int base = 10;
4220
4221 if (nargs > 1) {
4222 if ((base = tupregs[1].dttk_value) <= 1 ||
4223 base > ('z' - 'a' + 1) + ('9' - '0' + 1)) {
4224 *flags |= CPU_DTRACE_ILLOP;
4225 break;
4226 }
4227 }
4228
4229 val = (base == 10 && i < 0) ? i * -1 : i;
4230
4231 if (!DTRACE_INSCRATCH(mstate, size)) {
4232 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
4233 regs[rd] = NULL;
4234 break;
4235 }
4236
4237 for (*end-- = '\0'; val; val /= base) {
4238 if ((digit = val % base) <= '9' - '0') {
4239 *end-- = '0' + digit;
4240 } else {
4241 *end-- = 'a' + (digit - ('9' - '0') - 1);
4242 }
4243 }
4244
4245 if (i == 0 && base == 16)
4246 *end-- = '0';
4247
4248 if (base == 16)
4249 *end-- = 'x';
4250
4251 if (i == 0 || base == 8 || base == 16)
4252 *end-- = '0';
4253
4254 if (i < 0 && base == 10)
4255 *end-- = '-';
4256
4257 regs[rd] = (uintptr_t)end + 1;
4258 mstate->dtms_scratch_ptr += size;
4259 break;
4260 }
4261
4262 case DIF_SUBR_HTONS:
4263 case DIF_SUBR_NTOHS:
4264 #ifdef _BIG_ENDIAN
4265 regs[rd] = (uint16_t)tupregs[0].dttk_value;
4266 #else
4267 regs[rd] = DT_BSWAP_16((uint16_t)tupregs[0].dttk_value);
4268 #endif
4269 break;
4270
4271
4272 case DIF_SUBR_HTONL:
4273 case DIF_SUBR_NTOHL:
4274 #ifdef _BIG_ENDIAN
4275 regs[rd] = (uint32_t)tupregs[0].dttk_value;
4276 #else
4277 regs[rd] = DT_BSWAP_32((uint32_t)tupregs[0].dttk_value);
4278 #endif
4279 break;
4280
4281
4282 case DIF_SUBR_HTONLL:
4283 case DIF_SUBR_NTOHLL:
4284 #ifdef _BIG_ENDIAN
4285 regs[rd] = (uint64_t)tupregs[0].dttk_value;
4286 #else
4287 regs[rd] = DT_BSWAP_64((uint64_t)tupregs[0].dttk_value);
4288 #endif
4289 break;
4290
4291
4292 case DIF_SUBR_DIRNAME:
4293 case DIF_SUBR_BASENAME: {
4294 char *dest = (char *)mstate->dtms_scratch_ptr;
4295 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
4296 uintptr_t src = tupregs[0].dttk_value;
4297 int i, j, len = dtrace_strlen((char *)src, size);
4298 int lastbase = -1, firstbase = -1, lastdir = -1;
4299 int start, end;
4300
4301 if (!dtrace_canload(src, len + 1, mstate, vstate)) {
4302 regs[rd] = NULL;
4303 break;
4304 }
4305
4306 if (!DTRACE_INSCRATCH(mstate, size)) {
4307 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
4308 regs[rd] = NULL;
4309 break;
4310 }
4311
4312 /*
4313 * The basename and dirname for a zero-length string is
4314 * defined to be "."
4315 */
4316 if (len == 0) {
4317 len = 1;
4318 src = (uintptr_t)".";
4319 }
4320
4321 /*
4322 * Start from the back of the string, moving back toward the
4323 * front until we see a character that isn't a slash. That
4324 * character is the last character in the basename.
4325 */
4326 for (i = len - 1; i >= 0; i--) {
4327 if (dtrace_load8(src + i) != '/')
4328 break;
4329 }
4330
4331 if (i >= 0)
4332 lastbase = i;
4333
4334 /*
4335 * Starting from the last character in the basename, move
4336 * towards the front until we find a slash. The character
4337 * that we processed immediately before that is the first
4338 * character in the basename.
4339 */
4340 for (; i >= 0; i--) {
4341 if (dtrace_load8(src + i) == '/')
4342 break;
4343 }
4344
4345 if (i >= 0)
4346 firstbase = i + 1;
4347
4348 /*
4349 * Now keep going until we find a non-slash character. That
4350 * character is the last character in the dirname.
4351 */
4352 for (; i >= 0; i--) {
4353 if (dtrace_load8(src + i) != '/')
4354 break;
4355 }
4356
4357 if (i >= 0)
4358 lastdir = i;
4359
4360 ASSERT(!(lastbase == -1 && firstbase != -1));
4361 ASSERT(!(firstbase == -1 && lastdir != -1));
4362
4363 if (lastbase == -1) {
4364 /*
4365 * We didn't find a non-slash character. We know that
4366 * the length is non-zero, so the whole string must be
4367 * slashes. In either the dirname or the basename
4368 * case, we return '/'.
4369 */
4370 ASSERT(firstbase == -1);
4371 firstbase = lastbase = lastdir = 0;
4372 }
4373
4374 if (firstbase == -1) {
4375 /*
4376 * The entire string consists only of a basename
4377 * component. If we're looking for dirname, we need
4378 * to change our string to be just "."; if we're
4379 * looking for a basename, we'll just set the first
4380 * character of the basename to be 0.
4381 */
4382 if (subr == DIF_SUBR_DIRNAME) {
4383 ASSERT(lastdir == -1);
4384 src = (uintptr_t)".";
4385 lastdir = 0;
4386 } else {
4387 firstbase = 0;
4388 }
4389 }
4390
4391 if (subr == DIF_SUBR_DIRNAME) {
4392 if (lastdir == -1) {
4393 /*
4394 * We know that we have a slash in the name --
4395 * or lastdir would be set to 0, above. And
4396 * because lastdir is -1, we know that this
4397 * slash must be the first character. (That
4398 * is, the full string must be of the form
4399 * "/basename".) In this case, the last
4400 * character of the directory name is 0.
4401 */
4402 lastdir = 0;
4403 }
4404
4405 start = 0;
4406 end = lastdir;
4407 } else {
4408 ASSERT(subr == DIF_SUBR_BASENAME);
4409 ASSERT(firstbase != -1 && lastbase != -1);
4410 start = firstbase;
4411 end = lastbase;
4412 }
4413
4414 for (i = start, j = 0; i <= end && j < size - 1; i++, j++)
4415 dest[j] = dtrace_load8(src + i);
4416
4417 dest[j] = '\0';
4418 regs[rd] = (uintptr_t)dest;
4419 mstate->dtms_scratch_ptr += size;
4420 break;
4421 }
4422
4423 case DIF_SUBR_CLEANPATH: {
4424 char *dest = (char *)mstate->dtms_scratch_ptr, c;
4425 uint64_t size = state->dts_options[DTRACEOPT_STRSIZE];
4426 uintptr_t src = tupregs[0].dttk_value;
4427 int i = 0, j = 0;
4428
4429 if (!dtrace_strcanload(src, size, mstate, vstate)) {
4430 regs[rd] = NULL;
4431 break;
4432 }
4433
4434 if (!DTRACE_INSCRATCH(mstate, size)) {
4435 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
4436 regs[rd] = NULL;
4437 break;
4438 }
4439
4440 /*
4441 * Move forward, loading each character.
4442 */
4443 do {
4444 c = dtrace_load8(src + i++);
4445 next:
4446 if (j + 5 >= size) /* 5 = strlen("/..c\0") */
4447 break;
4448
4449 if (c != '/') {
4450 dest[j++] = c;
4451 continue;
4452 }
4453
4454 c = dtrace_load8(src + i++);
4455
4456 if (c == '/') {
4457 /*
4458 * We have two slashes -- we can just advance
4459 * to the next character.
4460 */
4461 goto next;
4462 }
4463
4464 if (c != '.') {
4465 /*
4466 * This is not "." and it's not ".." -- we can
4467 * just store the "/" and this character and
4468 * drive on.
4469 */
4470 dest[j++] = '/';
4471 dest[j++] = c;
4472 continue;
4473 }
4474
4475 c = dtrace_load8(src + i++);
4476
4477 if (c == '/') {
4478 /*
4479 * This is a "/./" component. We're not going
4480 * to store anything in the destination buffer;
4481 * we're just going to go to the next component.
4482 */
4483 goto next;
4484 }
4485
4486 if (c != '.') {
4487 /*
4488 * This is not ".." -- we can just store the
4489 * "/." and this character and continue
4490 * processing.
4491 */
4492 dest[j++] = '/';
4493 dest[j++] = '.';
4494 dest[j++] = c;
4495 continue;
4496 }
4497
4498 c = dtrace_load8(src + i++);
4499
4500 if (c != '/' && c != '\0') {
4501 /*
4502 * This is not ".." -- it's "..[mumble]".
4503 * We'll store the "/.." and this character
4504 * and continue processing.
4505 */
4506 dest[j++] = '/';
4507 dest[j++] = '.';
4508 dest[j++] = '.';
4509 dest[j++] = c;
4510 continue;
4511 }
4512
4513 /*
4514 * This is "/../" or "/..\0". We need to back up
4515 * our destination pointer until we find a "/".
4516 */
4517 i--;
4518 while (j != 0 && dest[--j] != '/')
4519 continue;
4520
4521 if (c == '\0')
4522 dest[++j] = '/';
4523 } while (c != '\0');
4524
4525 dest[j] = '\0';
4526 regs[rd] = (uintptr_t)dest;
4527 mstate->dtms_scratch_ptr += size;
4528 break;
4529 }
4530
4531 case DIF_SUBR_INET_NTOA:
4532 case DIF_SUBR_INET_NTOA6:
4533 case DIF_SUBR_INET_NTOP: {
4534 size_t size;
4535 int af, argi, i;
4536 char *base, *end;
4537
4538 if (subr == DIF_SUBR_INET_NTOP) {
4539 af = (int)tupregs[0].dttk_value;
4540 argi = 1;
4541 } else {
4542 af = subr == DIF_SUBR_INET_NTOA ? AF_INET: AF_INET6;
4543 argi = 0;
4544 }
4545
4546 if (af == AF_INET) {
4547 ipaddr_t ip4;
4548 uint8_t *ptr8, val;
4549
4550 /*
4551 * Safely load the IPv4 address.
4552 */
4553 ip4 = dtrace_load32(tupregs[argi].dttk_value);
4554
4555 /*
4556 * Check an IPv4 string will fit in scratch.
4557 */
4558 size = INET_ADDRSTRLEN;
4559 if (!DTRACE_INSCRATCH(mstate, size)) {
4560 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
4561 regs[rd] = NULL;
4562 break;
4563 }
4564 base = (char *)mstate->dtms_scratch_ptr;
4565 end = (char *)mstate->dtms_scratch_ptr + size - 1;
4566
4567 /*
4568 * Stringify as a dotted decimal quad.
4569 */
4570 *end-- = '\0';
4571 ptr8 = (uint8_t *)&ip4;
4572 for (i = 3; i >= 0; i--) {
4573 val = ptr8[i];
4574
4575 if (val == 0) {
4576 *end-- = '0';
4577 } else {
4578 for (; val; val /= 10) {
4579 *end-- = '0' + (val % 10);
4580 }
4581 }
4582
4583 if (i > 0)
4584 *end-- = '.';
4585 }
4586 ASSERT(end + 1 >= base);
4587
4588 } else if (af == AF_INET6) {
4589 struct in6_addr ip6;
4590 int firstzero, tryzero, numzero, v6end;
4591 uint16_t val;
4592 const char digits[] = "0123456789abcdef";
4593
4594 /*
4595 * Stringify using RFC 1884 convention 2 - 16 bit
4596 * hexadecimal values with a zero-run compression.
4597 * Lower case hexadecimal digits are used.
4598 * eg, fe80::214:4fff:fe0b:76c8.
4599 * The IPv4 embedded form is returned for inet_ntop,
4600 * just the IPv4 string is returned for inet_ntoa6.
4601 */
4602
4603 /*
4604 * Safely load the IPv6 address.
4605 */
4606 dtrace_bcopy(
4607 (void *)(uintptr_t)tupregs[argi].dttk_value,
4608 (void *)(uintptr_t)&ip6, sizeof (struct in6_addr));
4609
4610 /*
4611 * Check an IPv6 string will fit in scratch.
4612 */
4613 size = INET6_ADDRSTRLEN;
4614 if (!DTRACE_INSCRATCH(mstate, size)) {
4615 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
4616 regs[rd] = NULL;
4617 break;
4618 }
4619 base = (char *)mstate->dtms_scratch_ptr;
4620 end = (char *)mstate->dtms_scratch_ptr + size - 1;
4621 *end-- = '\0';
4622
4623 /*
4624 * Find the longest run of 16 bit zero values
4625 * for the single allowed zero compression - "::".
4626 */
4627 firstzero = -1;
4628 tryzero = -1;
4629 numzero = 1;
4630 for (i = 0; i < sizeof (struct in6_addr); i++) {
4631 if (ip6._S6_un._S6_u8[i] == 0 &&
4632 tryzero == -1 && i % 2 == 0) {
4633 tryzero = i;
4634 continue;
4635 }
4636
4637 if (tryzero != -1 &&
4638 (ip6._S6_un._S6_u8[i] != 0 ||
4639 i == sizeof (struct in6_addr) - 1)) {
4640
4641 if (i - tryzero <= numzero) {
4642 tryzero = -1;
4643 continue;
4644 }
4645
4646 firstzero = tryzero;
4647 numzero = i - i % 2 - tryzero;
4648 tryzero = -1;
4649
4650 if (ip6._S6_un._S6_u8[i] == 0 &&
4651 i == sizeof (struct in6_addr) - 1)
4652 numzero += 2;
4653 }
4654 }
4655 ASSERT(firstzero + numzero <= sizeof (struct in6_addr));
4656
4657 /*
4658 * Check for an IPv4 embedded address.
4659 */
4660 v6end = sizeof (struct in6_addr) - 2;
4661 if (IN6_IS_ADDR_V4MAPPED(&ip6) ||
4662 IN6_IS_ADDR_V4COMPAT(&ip6)) {
4663 for (i = sizeof (struct in6_addr) - 1;
4664 i >= DTRACE_V4MAPPED_OFFSET; i--) {
4665 ASSERT(end >= base);
4666
4667 val = ip6._S6_un._S6_u8[i];
4668
4669 if (val == 0) {
4670 *end-- = '0';
4671 } else {
4672 for (; val; val /= 10) {
4673 *end-- = '0' + val % 10;
4674 }
4675 }
4676
4677 if (i > DTRACE_V4MAPPED_OFFSET)
4678 *end-- = '.';
4679 }
4680
4681 if (subr == DIF_SUBR_INET_NTOA6)
4682 goto inetout;
4683
4684 /*
4685 * Set v6end to skip the IPv4 address that
4686 * we have already stringified.
4687 */
4688 v6end = 10;
4689 }
4690
4691 /*
4692 * Build the IPv6 string by working through the
4693 * address in reverse.
4694 */
4695 for (i = v6end; i >= 0; i -= 2) {
4696 ASSERT(end >= base);
4697
4698 if (i == firstzero + numzero - 2) {
4699 *end-- = ':';
4700 *end-- = ':';
4701 i -= numzero - 2;
4702 continue;
4703 }
4704
4705 if (i < 14 && i != firstzero - 2)
4706 *end-- = ':';
4707
4708 val = (ip6._S6_un._S6_u8[i] << 8) +
4709 ip6._S6_un._S6_u8[i + 1];
4710
4711 if (val == 0) {
4712 *end-- = '0';
4713 } else {
4714 for (; val; val /= 16) {
4715 *end-- = digits[val % 16];
4716 }
4717 }
4718 }
4719 ASSERT(end + 1 >= base);
4720
4721 } else {
4722 /*
4723 * The user didn't use AH_INET or AH_INET6.
4724 */
4725 DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP);
4726 regs[rd] = NULL;
4727 break;
4728 }
4729
4730 inetout: regs[rd] = (uintptr_t)end + 1;
4731 mstate->dtms_scratch_ptr += size;
4732 break;
4733 }
4734
4735 }
4736 }
4737
4738 /*
4739 * Emulate the execution of DTrace IR instructions specified by the given
4740 * DIF object. This function is deliberately void of assertions as all of
4741 * the necessary checks are handled by a call to dtrace_difo_validate().
4742 */
4743 static uint64_t
4744 dtrace_dif_emulate(dtrace_difo_t *difo, dtrace_mstate_t *mstate,
4745 dtrace_vstate_t *vstate, dtrace_state_t *state)
4746 {
4747 const dif_instr_t *text = difo->dtdo_buf;
4748 const uint_t textlen = difo->dtdo_len;
4749 const char *strtab = difo->dtdo_strtab;
4750 const uint64_t *inttab = difo->dtdo_inttab;
4751
4752 uint64_t rval = 0;
4753 dtrace_statvar_t *svar;
4754 dtrace_dstate_t *dstate = &vstate->dtvs_dynvars;
4755 dtrace_difv_t *v;
4756 volatile uint16_t *flags = &cpu_core[CPU->cpu_id].cpuc_dtrace_flags;
4757 volatile uintptr_t *illval = &cpu_core[CPU->cpu_id].cpuc_dtrace_illval;
4758
4759 dtrace_key_t tupregs[DIF_DTR_NREGS + 2]; /* +2 for thread and id */
4760 uint64_t regs[DIF_DIR_NREGS];
4761 uint64_t *tmp;
4762
4763 uint8_t cc_n = 0, cc_z = 0, cc_v = 0, cc_c = 0;
4764 int64_t cc_r;
4765 uint_t pc = 0, id, opc;
4766 uint8_t ttop = 0;
4767 dif_instr_t instr;
4768 uint_t r1, r2, rd;
4769
4770 /*
4771 * We stash the current DIF object into the machine state: we need it
4772 * for subsequent access checking.
4773 */
4774 mstate->dtms_difo = difo;
4775
4776 regs[DIF_REG_R0] = 0; /* %r0 is fixed at zero */
4777
4778 while (pc < textlen && !(*flags & CPU_DTRACE_FAULT)) {
4779 opc = pc;
4780
4781 instr = text[pc++];
4782 r1 = DIF_INSTR_R1(instr);
4783 r2 = DIF_INSTR_R2(instr);
4784 rd = DIF_INSTR_RD(instr);
4785
4786 switch (DIF_INSTR_OP(instr)) {
4787 case DIF_OP_OR:
4788 regs[rd] = regs[r1] | regs[r2];
4789 break;
4790 case DIF_OP_XOR:
4791 regs[rd] = regs[r1] ^ regs[r2];
4792 break;
4793 case DIF_OP_AND:
4794 regs[rd] = regs[r1] & regs[r2];
4795 break;
4796 case DIF_OP_SLL:
4797 regs[rd] = regs[r1] << regs[r2];
4798 break;
4799 case DIF_OP_SRL:
4800 regs[rd] = regs[r1] >> regs[r2];
4801 break;
4802 case DIF_OP_SUB:
4803 regs[rd] = regs[r1] - regs[r2];
4804 break;
4805 case DIF_OP_ADD:
4806 regs[rd] = regs[r1] + regs[r2];
4807 break;
4808 case DIF_OP_MUL:
4809 regs[rd] = regs[r1] * regs[r2];
4810 break;
4811 case DIF_OP_SDIV:
4812 if (regs[r2] == 0) {
4813 regs[rd] = 0;
4814 *flags |= CPU_DTRACE_DIVZERO;
4815 } else {
4816 regs[rd] = (int64_t)regs[r1] /
4817 (int64_t)regs[r2];
4818 }
4819 break;
4820
4821 case DIF_OP_UDIV:
4822 if (regs[r2] == 0) {
4823 regs[rd] = 0;
4824 *flags |= CPU_DTRACE_DIVZERO;
4825 } else {
4826 regs[rd] = regs[r1] / regs[r2];
4827 }
4828 break;
4829
4830 case DIF_OP_SREM:
4831 if (regs[r2] == 0) {
4832 regs[rd] = 0;
4833 *flags |= CPU_DTRACE_DIVZERO;
4834 } else {
4835 regs[rd] = (int64_t)regs[r1] %
4836 (int64_t)regs[r2];
4837 }
4838 break;
4839
4840 case DIF_OP_UREM:
4841 if (regs[r2] == 0) {
4842 regs[rd] = 0;
4843 *flags |= CPU_DTRACE_DIVZERO;
4844 } else {
4845 regs[rd] = regs[r1] % regs[r2];
4846 }
4847 break;
4848
4849 case DIF_OP_NOT:
4850 regs[rd] = ~regs[r1];
4851 break;
4852 case DIF_OP_MOV:
4853 regs[rd] = regs[r1];
4854 break;
4855 case DIF_OP_CMP:
4856 cc_r = regs[r1] - regs[r2];
4857 cc_n = cc_r < 0;
4858 cc_z = cc_r == 0;
4859 cc_v = 0;
4860 cc_c = regs[r1] < regs[r2];
4861 break;
4862 case DIF_OP_TST:
4863 cc_n = cc_v = cc_c = 0;
4864 cc_z = regs[r1] == 0;
4865 break;
4866 case DIF_OP_BA:
4867 pc = DIF_INSTR_LABEL(instr);
4868 break;
4869 case DIF_OP_BE:
4870 if (cc_z)
4871 pc = DIF_INSTR_LABEL(instr);
4872 break;
4873 case DIF_OP_BNE:
4874 if (cc_z == 0)
4875 pc = DIF_INSTR_LABEL(instr);
4876 break;
4877 case DIF_OP_BG:
4878 if ((cc_z | (cc_n ^ cc_v)) == 0)
4879 pc = DIF_INSTR_LABEL(instr);
4880 break;
4881 case DIF_OP_BGU:
4882 if ((cc_c | cc_z) == 0)
4883 pc = DIF_INSTR_LABEL(instr);
4884 break;
4885 case DIF_OP_BGE:
4886 if ((cc_n ^ cc_v) == 0)
4887 pc = DIF_INSTR_LABEL(instr);
4888 break;
4889 case DIF_OP_BGEU:
4890 if (cc_c == 0)
4891 pc = DIF_INSTR_LABEL(instr);
4892 break;
4893 case DIF_OP_BL:
4894 if (cc_n ^ cc_v)
4895 pc = DIF_INSTR_LABEL(instr);
4896 break;
4897 case DIF_OP_BLU:
4898 if (cc_c)
4899 pc = DIF_INSTR_LABEL(instr);
4900 break;
4901 case DIF_OP_BLE:
4902 if (cc_z | (cc_n ^ cc_v))
4903 pc = DIF_INSTR_LABEL(instr);
4904 break;
4905 case DIF_OP_BLEU:
4906 if (cc_c | cc_z)
4907 pc = DIF_INSTR_LABEL(instr);
4908 break;
4909 case DIF_OP_RLDSB:
4910 if (!dtrace_canstore(regs[r1], 1, mstate, vstate)) {
4911 *flags |= CPU_DTRACE_KPRIV;
4912 *illval = regs[r1];
4913 break;
4914 }
4915 /*FALLTHROUGH*/
4916 case DIF_OP_LDSB:
4917 regs[rd] = (int8_t)dtrace_load8(regs[r1]);
4918 break;
4919 case DIF_OP_RLDSH:
4920 if (!dtrace_canstore(regs[r1], 2, mstate, vstate)) {
4921 *flags |= CPU_DTRACE_KPRIV;
4922 *illval = regs[r1];
4923 break;
4924 }
4925 /*FALLTHROUGH*/
4926 case DIF_OP_LDSH:
4927 regs[rd] = (int16_t)dtrace_load16(regs[r1]);
4928 break;
4929 case DIF_OP_RLDSW:
4930 if (!dtrace_canstore(regs[r1], 4, mstate, vstate)) {
4931 *flags |= CPU_DTRACE_KPRIV;
4932 *illval = regs[r1];
4933 break;
4934 }
4935 /*FALLTHROUGH*/
4936 case DIF_OP_LDSW:
4937 regs[rd] = (int32_t)dtrace_load32(regs[r1]);
4938 break;
4939 case DIF_OP_RLDUB:
4940 if (!dtrace_canstore(regs[r1], 1, mstate, vstate)) {
4941 *flags |= CPU_DTRACE_KPRIV;
4942 *illval = regs[r1];
4943 break;
4944 }
4945 /*FALLTHROUGH*/
4946 case DIF_OP_LDUB:
4947 regs[rd] = dtrace_load8(regs[r1]);
4948 break;
4949 case DIF_OP_RLDUH:
4950 if (!dtrace_canstore(regs[r1], 2, mstate, vstate)) {
4951 *flags |= CPU_DTRACE_KPRIV;
4952 *illval = regs[r1];
4953 break;
4954 }
4955 /*FALLTHROUGH*/
4956 case DIF_OP_LDUH:
4957 regs[rd] = dtrace_load16(regs[r1]);
4958 break;
4959 case DIF_OP_RLDUW:
4960 if (!dtrace_canstore(regs[r1], 4, mstate, vstate)) {
4961 *flags |= CPU_DTRACE_KPRIV;
4962 *illval = regs[r1];
4963 break;
4964 }
4965 /*FALLTHROUGH*/
4966 case DIF_OP_LDUW:
4967 regs[rd] = dtrace_load32(regs[r1]);
4968 break;
4969 case DIF_OP_RLDX:
4970 if (!dtrace_canstore(regs[r1], 8, mstate, vstate)) {
4971 *flags |= CPU_DTRACE_KPRIV;
4972 *illval = regs[r1];
4973 break;
4974 }
4975 /*FALLTHROUGH*/
4976 case DIF_OP_LDX:
4977 regs[rd] = dtrace_load64(regs[r1]);
4978 break;
4979 case DIF_OP_ULDSB:
4980 regs[rd] = (int8_t)
4981 dtrace_fuword8((void *)(uintptr_t)regs[r1]);
4982 break;
4983 case DIF_OP_ULDSH:
4984 regs[rd] = (int16_t)
4985 dtrace_fuword16((void *)(uintptr_t)regs[r1]);
4986 break;
4987 case DIF_OP_ULDSW:
4988 regs[rd] = (int32_t)
4989 dtrace_fuword32((void *)(uintptr_t)regs[r1]);
4990 break;
4991 case DIF_OP_ULDUB:
4992 regs[rd] =
4993 dtrace_fuword8((void *)(uintptr_t)regs[r1]);
4994 break;
4995 case DIF_OP_ULDUH:
4996 regs[rd] =
4997 dtrace_fuword16((void *)(uintptr_t)regs[r1]);
4998 break;
4999 case DIF_OP_ULDUW:
5000 regs[rd] =
5001 dtrace_fuword32((void *)(uintptr_t)regs[r1]);
5002 break;
5003 case DIF_OP_ULDX:
5004 regs[rd] =
5005 dtrace_fuword64((void *)(uintptr_t)regs[r1]);
5006 break;
5007 case DIF_OP_RET:
5008 rval = regs[rd];
5009 pc = textlen;
5010 break;
5011 case DIF_OP_NOP:
5012 break;
5013 case DIF_OP_SETX:
5014 regs[rd] = inttab[DIF_INSTR_INTEGER(instr)];
5015 break;
5016 case DIF_OP_SETS:
5017 regs[rd] = (uint64_t)(uintptr_t)
5018 (strtab + DIF_INSTR_STRING(instr));
5019 break;
5020 case DIF_OP_SCMP: {
5021 size_t sz = state->dts_options[DTRACEOPT_STRSIZE];
5022 uintptr_t s1 = regs[r1];
5023 uintptr_t s2 = regs[r2];
5024
5025 if (s1 != NULL &&
5026 !dtrace_strcanload(s1, sz, mstate, vstate))
5027 break;
5028 if (s2 != NULL &&
5029 !dtrace_strcanload(s2, sz, mstate, vstate))
5030 break;
5031
5032 cc_r = dtrace_strncmp((char *)s1, (char *)s2, sz);
5033
5034 cc_n = cc_r < 0;
5035 cc_z = cc_r == 0;
5036 cc_v = cc_c = 0;
5037 break;
5038 }
5039 case DIF_OP_LDGA:
5040 regs[rd] = dtrace_dif_variable(mstate, state,
5041 r1, regs[r2]);
5042 break;
5043 case DIF_OP_LDGS:
5044 id = DIF_INSTR_VAR(instr);
5045
5046 if (id >= DIF_VAR_OTHER_UBASE) {
5047 uintptr_t a;
5048
5049 id -= DIF_VAR_OTHER_UBASE;
5050 svar = vstate->dtvs_globals[id];
5051 ASSERT(svar != NULL);
5052 v = &svar->dtsv_var;
5053
5054 if (!(v->dtdv_type.dtdt_flags & DIF_TF_BYREF)) {
5055 regs[rd] = svar->dtsv_data;
5056 break;
5057 }
5058
5059 a = (uintptr_t)svar->dtsv_data;
5060
5061 if (*(uint8_t *)a == UINT8_MAX) {
5062 /*
5063 * If the 0th byte is set to UINT8_MAX
5064 * then this is to be treated as a
5065 * reference to a NULL variable.
5066 */
5067 regs[rd] = NULL;
5068 } else {
5069 regs[rd] = a + sizeof (uint64_t);
5070 }
5071
5072 break;
5073 }
5074
5075 regs[rd] = dtrace_dif_variable(mstate, state, id, 0);
5076 break;
5077
5078 case DIF_OP_STGS:
5079 id = DIF_INSTR_VAR(instr);
5080
5081 ASSERT(id >= DIF_VAR_OTHER_UBASE);
5082 id -= DIF_VAR_OTHER_UBASE;
5083
5084 svar = vstate->dtvs_globals[id];
5085 ASSERT(svar != NULL);
5086 v = &svar->dtsv_var;
5087
5088 if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) {
5089 uintptr_t a = (uintptr_t)svar->dtsv_data;
5090
5091 ASSERT(a != NULL);
5092 ASSERT(svar->dtsv_size != 0);
5093
5094 if (regs[rd] == NULL) {
5095 *(uint8_t *)a = UINT8_MAX;
5096 break;
5097 } else {
5098 *(uint8_t *)a = 0;
5099 a += sizeof (uint64_t);
5100 }
5101 if (!dtrace_vcanload(
5102 (void *)(uintptr_t)regs[rd], &v->dtdv_type,
5103 mstate, vstate))
5104 break;
5105
5106 dtrace_vcopy((void *)(uintptr_t)regs[rd],
5107 (void *)a, &v->dtdv_type);
5108 break;
5109 }
5110
5111 svar->dtsv_data = regs[rd];
5112 break;
5113
5114 case DIF_OP_LDTA:
5115 /*
5116 * There are no DTrace built-in thread-local arrays at
5117 * present. This opcode is saved for future work.
5118 */
5119 *flags |= CPU_DTRACE_ILLOP;
5120 regs[rd] = 0;
5121 break;
5122
5123 case DIF_OP_LDLS:
5124 id = DIF_INSTR_VAR(instr);
5125
5126 if (id < DIF_VAR_OTHER_UBASE) {
5127 /*
5128 * For now, this has no meaning.
5129 */
5130 regs[rd] = 0;
5131 break;
5132 }
5133
5134 id -= DIF_VAR_OTHER_UBASE;
5135
5136 ASSERT(id < vstate->dtvs_nlocals);
5137 ASSERT(vstate->dtvs_locals != NULL);
5138
5139 svar = vstate->dtvs_locals[id];
5140 ASSERT(svar != NULL);
5141 v = &svar->dtsv_var;
5142
5143 if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) {
5144 uintptr_t a = (uintptr_t)svar->dtsv_data;
5145 size_t sz = v->dtdv_type.dtdt_size;
5146
5147 sz += sizeof (uint64_t);
5148 ASSERT(svar->dtsv_size == NCPU * sz);
5149 a += CPU->cpu_id * sz;
5150
5151 if (*(uint8_t *)a == UINT8_MAX) {
5152 /*
5153 * If the 0th byte is set to UINT8_MAX
5154 * then this is to be treated as a
5155 * reference to a NULL variable.
5156 */
5157 regs[rd] = NULL;
5158 } else {
5159 regs[rd] = a + sizeof (uint64_t);
5160 }
5161
5162 break;
5163 }
5164
5165 ASSERT(svar->dtsv_size == NCPU * sizeof (uint64_t));
5166 tmp = (uint64_t *)(uintptr_t)svar->dtsv_data;
5167 regs[rd] = tmp[CPU->cpu_id];
5168 break;
5169
5170 case DIF_OP_STLS:
5171 id = DIF_INSTR_VAR(instr);
5172
5173 ASSERT(id >= DIF_VAR_OTHER_UBASE);
5174 id -= DIF_VAR_OTHER_UBASE;
5175 ASSERT(id < vstate->dtvs_nlocals);
5176
5177 ASSERT(vstate->dtvs_locals != NULL);
5178 svar = vstate->dtvs_locals[id];
5179 ASSERT(svar != NULL);
5180 v = &svar->dtsv_var;
5181
5182 if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) {
5183 uintptr_t a = (uintptr_t)svar->dtsv_data;
5184 size_t sz = v->dtdv_type.dtdt_size;
5185
5186 sz += sizeof (uint64_t);
5187 ASSERT(svar->dtsv_size == NCPU * sz);
5188 a += CPU->cpu_id * sz;
5189
5190 if (regs[rd] == NULL) {
5191 *(uint8_t *)a = UINT8_MAX;
5192 break;
5193 } else {
5194 *(uint8_t *)a = 0;
5195 a += sizeof (uint64_t);
5196 }
5197
5198 if (!dtrace_vcanload(
5199 (void *)(uintptr_t)regs[rd], &v->dtdv_type,
5200 mstate, vstate))
5201 break;
5202
5203 dtrace_vcopy((void *)(uintptr_t)regs[rd],
5204 (void *)a, &v->dtdv_type);
5205 break;
5206 }
5207
5208 ASSERT(svar->dtsv_size == NCPU * sizeof (uint64_t));
5209 tmp = (uint64_t *)(uintptr_t)svar->dtsv_data;
5210 tmp[CPU->cpu_id] = regs[rd];
5211 break;
5212
5213 case DIF_OP_LDTS: {
5214 dtrace_dynvar_t *dvar;
5215 dtrace_key_t *key;
5216
5217 id = DIF_INSTR_VAR(instr);
5218 ASSERT(id >= DIF_VAR_OTHER_UBASE);
5219 id -= DIF_VAR_OTHER_UBASE;
5220 v = &vstate->dtvs_tlocals[id];
5221
5222 key = &tupregs[DIF_DTR_NREGS];
5223 key[0].dttk_value = (uint64_t)id;
5224 key[0].dttk_size = 0;
5225 DTRACE_TLS_THRKEY(key[1].dttk_value);
5226 key[1].dttk_size = 0;
5227
5228 dvar = dtrace_dynvar(dstate, 2, key,
5229 sizeof (uint64_t), DTRACE_DYNVAR_NOALLOC,
5230 mstate, vstate);
5231
5232 if (dvar == NULL) {
5233 regs[rd] = 0;
5234 break;
5235 }
5236
5237 if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) {
5238 regs[rd] = (uint64_t)(uintptr_t)dvar->dtdv_data;
5239 } else {
5240 regs[rd] = *((uint64_t *)dvar->dtdv_data);
5241 }
5242
5243 break;
5244 }
5245
5246 case DIF_OP_STTS: {
5247 dtrace_dynvar_t *dvar;
5248 dtrace_key_t *key;
5249
5250 id = DIF_INSTR_VAR(instr);
5251 ASSERT(id >= DIF_VAR_OTHER_UBASE);
5252 id -= DIF_VAR_OTHER_UBASE;
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 v = &vstate->dtvs_tlocals[id];
5260
5261 dvar = dtrace_dynvar(dstate, 2, key,
5262 v->dtdv_type.dtdt_size > sizeof (uint64_t) ?
5263 v->dtdv_type.dtdt_size : sizeof (uint64_t),
5264 regs[rd] ? DTRACE_DYNVAR_ALLOC :
5265 DTRACE_DYNVAR_DEALLOC, mstate, vstate);
5266
5267 /*
5268 * Given that we're storing to thread-local data,
5269 * we need to flush our predicate cache.
5270 */
5271 curthread->t_predcache = NULL;
5272
5273 if (dvar == NULL)
5274 break;
5275
5276 if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) {
5277 if (!dtrace_vcanload(
5278 (void *)(uintptr_t)regs[rd],
5279 &v->dtdv_type, mstate, vstate))
5280 break;
5281
5282 dtrace_vcopy((void *)(uintptr_t)regs[rd],
5283 dvar->dtdv_data, &v->dtdv_type);
5284 } else {
5285 *((uint64_t *)dvar->dtdv_data) = regs[rd];
5286 }
5287
5288 break;
5289 }
5290
5291 case DIF_OP_SRA:
5292 regs[rd] = (int64_t)regs[r1] >> regs[r2];
5293 break;
5294
5295 case DIF_OP_CALL:
5296 dtrace_dif_subr(DIF_INSTR_SUBR(instr), rd,
5297 regs, tupregs, ttop, mstate, state);
5298 break;
5299
5300 case DIF_OP_PUSHTR:
5301 if (ttop == DIF_DTR_NREGS) {
5302 *flags |= CPU_DTRACE_TUPOFLOW;
5303 break;
5304 }
5305
5306 if (r1 == DIF_TYPE_STRING) {
5307 /*
5308 * If this is a string type and the size is 0,
5309 * we'll use the system-wide default string
5310 * size. Note that we are _not_ looking at
5311 * the value of the DTRACEOPT_STRSIZE option;
5312 * had this been set, we would expect to have
5313 * a non-zero size value in the "pushtr".
5314 */
5315 tupregs[ttop].dttk_size =
5316 dtrace_strlen((char *)(uintptr_t)regs[rd],
5317 regs[r2] ? regs[r2] :
5318 dtrace_strsize_default) + 1;
5319 } else {
5320 tupregs[ttop].dttk_size = regs[r2];
5321 }
5322
5323 tupregs[ttop++].dttk_value = regs[rd];
5324 break;
5325
5326 case DIF_OP_PUSHTV:
5327 if (ttop == DIF_DTR_NREGS) {
5328 *flags |= CPU_DTRACE_TUPOFLOW;
5329 break;
5330 }
5331
5332 tupregs[ttop].dttk_value = regs[rd];
5333 tupregs[ttop++].dttk_size = 0;
5334 break;
5335
5336 case DIF_OP_POPTS:
5337 if (ttop != 0)
5338 ttop--;
5339 break;
5340
5341 case DIF_OP_FLUSHTS:
5342 ttop = 0;
5343 break;
5344
5345 case DIF_OP_LDGAA:
5346 case DIF_OP_LDTAA: {
5347 dtrace_dynvar_t *dvar;
5348 dtrace_key_t *key = tupregs;
5349 uint_t nkeys = ttop;
5350
5351 id = DIF_INSTR_VAR(instr);
5352 ASSERT(id >= DIF_VAR_OTHER_UBASE);
5353 id -= DIF_VAR_OTHER_UBASE;
5354
5355 key[nkeys].dttk_value = (uint64_t)id;
5356 key[nkeys++].dttk_size = 0;
5357
5358 if (DIF_INSTR_OP(instr) == DIF_OP_LDTAA) {
5359 DTRACE_TLS_THRKEY(key[nkeys].dttk_value);
5360 key[nkeys++].dttk_size = 0;
5361 v = &vstate->dtvs_tlocals[id];
5362 } else {
5363 v = &vstate->dtvs_globals[id]->dtsv_var;
5364 }
5365
5366 dvar = dtrace_dynvar(dstate, nkeys, key,
5367 v->dtdv_type.dtdt_size > sizeof (uint64_t) ?
5368 v->dtdv_type.dtdt_size : sizeof (uint64_t),
5369 DTRACE_DYNVAR_NOALLOC, mstate, vstate);
5370
5371 if (dvar == NULL) {
5372 regs[rd] = 0;
5373 break;
5374 }
5375
5376 if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) {
5377 regs[rd] = (uint64_t)(uintptr_t)dvar->dtdv_data;
5378 } else {
5379 regs[rd] = *((uint64_t *)dvar->dtdv_data);
5380 }
5381
5382 break;
5383 }
5384
5385 case DIF_OP_STGAA:
5386 case DIF_OP_STTAA: {
5387 dtrace_dynvar_t *dvar;
5388 dtrace_key_t *key = tupregs;
5389 uint_t nkeys = ttop;
5390
5391 id = DIF_INSTR_VAR(instr);
5392 ASSERT(id >= DIF_VAR_OTHER_UBASE);
5393 id -= DIF_VAR_OTHER_UBASE;
5394
5395 key[nkeys].dttk_value = (uint64_t)id;
5396 key[nkeys++].dttk_size = 0;
5397
5398 if (DIF_INSTR_OP(instr) == DIF_OP_STTAA) {
5399 DTRACE_TLS_THRKEY(key[nkeys].dttk_value);
5400 key[nkeys++].dttk_size = 0;
5401 v = &vstate->dtvs_tlocals[id];
5402 } else {
5403 v = &vstate->dtvs_globals[id]->dtsv_var;
5404 }
5405
5406 dvar = dtrace_dynvar(dstate, nkeys, key,
5407 v->dtdv_type.dtdt_size > sizeof (uint64_t) ?
5408 v->dtdv_type.dtdt_size : sizeof (uint64_t),
5409 regs[rd] ? DTRACE_DYNVAR_ALLOC :
5410 DTRACE_DYNVAR_DEALLOC, mstate, vstate);
5411
5412 if (dvar == NULL)
5413 break;
5414
5415 if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF) {
5416 if (!dtrace_vcanload(
5417 (void *)(uintptr_t)regs[rd], &v->dtdv_type,
5418 mstate, vstate))
5419 break;
5420
5421 dtrace_vcopy((void *)(uintptr_t)regs[rd],
5422 dvar->dtdv_data, &v->dtdv_type);
5423 } else {
5424 *((uint64_t *)dvar->dtdv_data) = regs[rd];
5425 }
5426
5427 break;
5428 }
5429
5430 case DIF_OP_ALLOCS: {
5431 uintptr_t ptr = P2ROUNDUP(mstate->dtms_scratch_ptr, 8);
5432 size_t size = ptr - mstate->dtms_scratch_ptr + regs[r1];
5433
5434 /*
5435 * Rounding up the user allocation size could have
5436 * overflowed large, bogus allocations (like -1ULL) to
5437 * 0.
5438 */
5439 if (size < regs[r1] ||
5440 !DTRACE_INSCRATCH(mstate, size)) {
5441 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
5442 regs[rd] = NULL;
5443 break;
5444 }
5445
5446 dtrace_bzero((void *) mstate->dtms_scratch_ptr, size);
5447 mstate->dtms_scratch_ptr += size;
5448 regs[rd] = ptr;
5449 break;
5450 }
5451
5452 case DIF_OP_COPYS:
5453 if (!dtrace_canstore(regs[rd], regs[r2],
5454 mstate, vstate)) {
5455 *flags |= CPU_DTRACE_BADADDR;
5456 *illval = regs[rd];
5457 break;
5458 }
5459
5460 if (!dtrace_canload(regs[r1], regs[r2], mstate, vstate))
5461 break;
5462
5463 dtrace_bcopy((void *)(uintptr_t)regs[r1],
5464 (void *)(uintptr_t)regs[rd], (size_t)regs[r2]);
5465 break;
5466
5467 case DIF_OP_STB:
5468 if (!dtrace_canstore(regs[rd], 1, mstate, vstate)) {
5469 *flags |= CPU_DTRACE_BADADDR;
5470 *illval = regs[rd];
5471 break;
5472 }
5473 *((uint8_t *)(uintptr_t)regs[rd]) = (uint8_t)regs[r1];
5474 break;
5475
5476 case DIF_OP_STH:
5477 if (!dtrace_canstore(regs[rd], 2, mstate, vstate)) {
5478 *flags |= CPU_DTRACE_BADADDR;
5479 *illval = regs[rd];
5480 break;
5481 }
5482 if (regs[rd] & 1) {
5483 *flags |= CPU_DTRACE_BADALIGN;
5484 *illval = regs[rd];
5485 break;
5486 }
5487 *((uint16_t *)(uintptr_t)regs[rd]) = (uint16_t)regs[r1];
5488 break;
5489
5490 case DIF_OP_STW:
5491 if (!dtrace_canstore(regs[rd], 4, mstate, vstate)) {
5492 *flags |= CPU_DTRACE_BADADDR;
5493 *illval = regs[rd];
5494 break;
5495 }
5496 if (regs[rd] & 3) {
5497 *flags |= CPU_DTRACE_BADALIGN;
5498 *illval = regs[rd];
5499 break;
5500 }
5501 *((uint32_t *)(uintptr_t)regs[rd]) = (uint32_t)regs[r1];
5502 break;
5503
5504 case DIF_OP_STX:
5505 if (!dtrace_canstore(regs[rd], 8, mstate, vstate)) {
5506 *flags |= CPU_DTRACE_BADADDR;
5507 *illval = regs[rd];
5508 break;
5509 }
5510 if (regs[rd] & 7) {
5511 *flags |= CPU_DTRACE_BADALIGN;
5512 *illval = regs[rd];
5513 break;
5514 }
5515 *((uint64_t *)(uintptr_t)regs[rd]) = regs[r1];
5516 break;
5517 }
5518 }
5519
5520 if (!(*flags & CPU_DTRACE_FAULT))
5521 return (rval);
5522
5523 mstate->dtms_fltoffs = opc * sizeof (dif_instr_t);
5524 mstate->dtms_present |= DTRACE_MSTATE_FLTOFFS;
5525
5526 return (0);
5527 }
5528
5529 static void
5530 dtrace_action_breakpoint(dtrace_ecb_t *ecb)
5531 {
5532 dtrace_probe_t *probe = ecb->dte_probe;
5533 dtrace_provider_t *prov = probe->dtpr_provider;
5534 char c[DTRACE_FULLNAMELEN + 80], *str;
5535 char *msg = "dtrace: breakpoint action at probe ";
5536 char *ecbmsg = " (ecb ";
5537 uintptr_t mask = (0xf << (sizeof (uintptr_t) * NBBY / 4));
5538 uintptr_t val = (uintptr_t)ecb;
5539 int shift = (sizeof (uintptr_t) * NBBY) - 4, i = 0;
5540
5541 if (dtrace_destructive_disallow)
5542 return;
5543
5544 /*
5545 * It's impossible to be taking action on the NULL probe.
5546 */
5547 ASSERT(probe != NULL);
5548
5549 /*
5550 * This is a poor man's (destitute man's?) sprintf(): we want to
5551 * print the provider name, module name, function name and name of
5552 * the probe, along with the hex address of the ECB with the breakpoint
5553 * action -- all of which we must place in the character buffer by
5554 * hand.
5555 */
5556 while (*msg != '\0')
5557 c[i++] = *msg++;
5558
5559 for (str = prov->dtpv_name; *str != '\0'; str++)
5560 c[i++] = *str;
5561 c[i++] = ':';
5562
5563 for (str = probe->dtpr_mod; *str != '\0'; str++)
5564 c[i++] = *str;
5565 c[i++] = ':';
5566
5567 for (str = probe->dtpr_func; *str != '\0'; str++)
5568 c[i++] = *str;
5569 c[i++] = ':';
5570
5571 for (str = probe->dtpr_name; *str != '\0'; str++)
5572 c[i++] = *str;
5573
5574 while (*ecbmsg != '\0')
5575 c[i++] = *ecbmsg++;
5576
5577 while (shift >= 0) {
5578 mask = (uintptr_t)0xf << shift;
5579
5580 if (val >= ((uintptr_t)1 << shift))
5581 c[i++] = "0123456789abcdef"[(val & mask) >> shift];
5582 shift -= 4;
5583 }
5584
5585 c[i++] = ')';
5586 c[i] = '\0';
5587
5588 debug_enter(c);
5589 }
5590
5591 static void
5592 dtrace_action_panic(dtrace_ecb_t *ecb)
5593 {
5594 dtrace_probe_t *probe = ecb->dte_probe;
5595
5596 /*
5597 * It's impossible to be taking action on the NULL probe.
5598 */
5599 ASSERT(probe != NULL);
5600
5601 if (dtrace_destructive_disallow)
5602 return;
5603
5604 if (dtrace_panicked != NULL)
5605 return;
5606
5607 if (dtrace_casptr(&dtrace_panicked, NULL, curthread) != NULL)
5608 return;
5609
5610 /*
5611 * We won the right to panic. (We want to be sure that only one
5612 * thread calls panic() from dtrace_probe(), and that panic() is
5613 * called exactly once.)
5614 */
5615 dtrace_panic("dtrace: panic action at probe %s:%s:%s:%s (ecb %p)",
5616 probe->dtpr_provider->dtpv_name, probe->dtpr_mod,
5617 probe->dtpr_func, probe->dtpr_name, (void *)ecb);
5618 }
5619
5620 static void
5621 dtrace_action_raise(uint64_t sig)
5622 {
5623 if (dtrace_destructive_disallow)
5624 return;
5625
5626 if (sig >= NSIG) {
5627 DTRACE_CPUFLAG_SET(CPU_DTRACE_ILLOP);
5628 return;
5629 }
5630
5631 /*
5632 * raise() has a queue depth of 1 -- we ignore all subsequent
5633 * invocations of the raise() action.
5634 */
5635 if (curthread->t_dtrace_sig == 0)
5636 curthread->t_dtrace_sig = (uint8_t)sig;
5637
5638 curthread->t_sig_check = 1;
5639 aston(curthread);
5640 }
5641
5642 static void
5643 dtrace_action_stop(void)
5644 {
5645 if (dtrace_destructive_disallow)
5646 return;
5647
5648 if (!curthread->t_dtrace_stop) {
5649 curthread->t_dtrace_stop = 1;
5650 curthread->t_sig_check = 1;
5651 aston(curthread);
5652 }
5653 }
5654
5655 static void
5656 dtrace_action_chill(dtrace_mstate_t *mstate, hrtime_t val)
5657 {
5658 hrtime_t now;
5659 volatile uint16_t *flags;
5660 cpu_t *cpu = CPU;
5661
5662 if (dtrace_destructive_disallow)
5663 return;
5664
5665 flags = (volatile uint16_t *)&cpu_core[cpu->cpu_id].cpuc_dtrace_flags;
5666
5667 now = dtrace_gethrtime();
5668
5669 if (now - cpu->cpu_dtrace_chillmark > dtrace_chill_interval) {
5670 /*
5671 * We need to advance the mark to the current time.
5672 */
5673 cpu->cpu_dtrace_chillmark = now;
5674 cpu->cpu_dtrace_chilled = 0;
5675 }
5676
5677 /*
5678 * Now check to see if the requested chill time would take us over
5679 * the maximum amount of time allowed in the chill interval. (Or
5680 * worse, if the calculation itself induces overflow.)
5681 */
5682 if (cpu->cpu_dtrace_chilled + val > dtrace_chill_max ||
5683 cpu->cpu_dtrace_chilled + val < cpu->cpu_dtrace_chilled) {
5684 *flags |= CPU_DTRACE_ILLOP;
5685 return;
5686 }
5687
5688 while (dtrace_gethrtime() - now < val)
5689 continue;
5690
5691 /*
5692 * Normally, we assure that the value of the variable "timestamp" does
5693 * not change within an ECB. The presence of chill() represents an
5694 * exception to this rule, however.
5695 */
5696 mstate->dtms_present &= ~DTRACE_MSTATE_TIMESTAMP;
5697 cpu->cpu_dtrace_chilled += val;
5698 }
5699
5700 static void
5701 dtrace_action_ustack(dtrace_mstate_t *mstate, dtrace_state_t *state,
5702 uint64_t *buf, uint64_t arg)
5703 {
5704 int nframes = DTRACE_USTACK_NFRAMES(arg);
5705 int strsize = DTRACE_USTACK_STRSIZE(arg);
5706 uint64_t *pcs = &buf[1], *fps;
5707 char *str = (char *)&pcs[nframes];
5708 int size, offs = 0, i, j;
5709 uintptr_t old = mstate->dtms_scratch_ptr, saved;
5710 uint16_t *flags = &cpu_core[CPU->cpu_id].cpuc_dtrace_flags;
5711 char *sym;
5712
5713 /*
5714 * Should be taking a faster path if string space has not been
5715 * allocated.
5716 */
5717 ASSERT(strsize != 0);
5718
5719 /*
5720 * We will first allocate some temporary space for the frame pointers.
5721 */
5722 fps = (uint64_t *)P2ROUNDUP(mstate->dtms_scratch_ptr, 8);
5723 size = (uintptr_t)fps - mstate->dtms_scratch_ptr +
5724 (nframes * sizeof (uint64_t));
5725
5726 if (!DTRACE_INSCRATCH(mstate, size)) {
5727 /*
5728 * Not enough room for our frame pointers -- need to indicate
5729 * that we ran out of scratch space.
5730 */
5731 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOSCRATCH);
5732 return;
5733 }
5734
5735 mstate->dtms_scratch_ptr += size;
5736 saved = mstate->dtms_scratch_ptr;
5737
5738 /*
5739 * Now get a stack with both program counters and frame pointers.
5740 */
5741 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
5742 dtrace_getufpstack(buf, fps, nframes + 1);
5743 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
5744
5745 /*
5746 * If that faulted, we're cooked.
5747 */
5748 if (*flags & CPU_DTRACE_FAULT)
5749 goto out;
5750
5751 /*
5752 * Now we want to walk up the stack, calling the USTACK helper. For
5753 * each iteration, we restore the scratch pointer.
5754 */
5755 for (i = 0; i < nframes; i++) {
5756 mstate->dtms_scratch_ptr = saved;
5757
5758 if (offs >= strsize)
5759 break;
5760
5761 sym = (char *)(uintptr_t)dtrace_helper(
5762 DTRACE_HELPER_ACTION_USTACK,
5763 mstate, state, pcs[i], fps[i]);
5764
5765 /*
5766 * If we faulted while running the helper, we're going to
5767 * clear the fault and null out the corresponding string.
5768 */
5769 if (*flags & CPU_DTRACE_FAULT) {
5770 *flags &= ~CPU_DTRACE_FAULT;
5771 str[offs++] = '\0';
5772 continue;
5773 }
5774
5775 if (sym == NULL) {
5776 str[offs++] = '\0';
5777 continue;
5778 }
5779
5780 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
5781
5782 /*
5783 * Now copy in the string that the helper returned to us.
5784 */
5785 for (j = 0; offs + j < strsize; j++) {
5786 if ((str[offs + j] = sym[j]) == '\0')
5787 break;
5788 }
5789
5790 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
5791
5792 offs += j + 1;
5793 }
5794
5795 if (offs >= strsize) {
5796 /*
5797 * If we didn't have room for all of the strings, we don't
5798 * abort processing -- this needn't be a fatal error -- but we
5799 * still want to increment a counter (dts_stkstroverflows) to
5800 * allow this condition to be warned about. (If this is from
5801 * a jstack() action, it is easily tuned via jstackstrsize.)
5802 */
5803 dtrace_error(&state->dts_stkstroverflows);
5804 }
5805
5806 while (offs < strsize)
5807 str[offs++] = '\0';
5808
5809 out:
5810 mstate->dtms_scratch_ptr = old;
5811 }
5812
5813 /*
5814 * If you're looking for the epicenter of DTrace, you just found it. This
5815 * is the function called by the provider to fire a probe -- from which all
5816 * subsequent probe-context DTrace activity emanates.
5817 */
5818 void
5819 dtrace_probe(dtrace_id_t id, uintptr_t arg0, uintptr_t arg1,
5820 uintptr_t arg2, uintptr_t arg3, uintptr_t arg4)
5821 {
5822 processorid_t cpuid;
5823 dtrace_icookie_t cookie;
5824 dtrace_probe_t *probe;
5825 dtrace_mstate_t mstate;
5826 dtrace_ecb_t *ecb;
5827 dtrace_action_t *act;
5828 intptr_t offs;
5829 size_t size;
5830 int vtime, onintr;
5831 volatile uint16_t *flags;
5832 hrtime_t now;
5833
5834 /*
5835 * Kick out immediately if this CPU is still being born (in which case
5836 * curthread will be set to -1) or the current thread can't allow
5837 * probes in its current context.
5838 */
5839 if (((uintptr_t)curthread & 1) || (curthread->t_flag & T_DONTDTRACE))
5840 return;
5841
5842 cookie = dtrace_interrupt_disable();
5843 probe = dtrace_probes[id - 1];
5844 cpuid = CPU->cpu_id;
5845 onintr = CPU_ON_INTR(CPU);
5846
5847 if (!onintr && probe->dtpr_predcache != DTRACE_CACHEIDNONE &&
5848 probe->dtpr_predcache == curthread->t_predcache) {
5849 /*
5850 * We have hit in the predicate cache; we know that
5851 * this predicate would evaluate to be false.
5852 */
5853 dtrace_interrupt_enable(cookie);
5854 return;
5855 }
5856
5857 if (panic_quiesce) {
5858 /*
5859 * We don't trace anything if we're panicking.
5860 */
5861 dtrace_interrupt_enable(cookie);
5862 return;
5863 }
5864
5865 now = dtrace_gethrtime();
5866 vtime = dtrace_vtime_references != 0;
5867
5868 if (vtime && curthread->t_dtrace_start)
5869 curthread->t_dtrace_vtime += now - curthread->t_dtrace_start;
5870
5871 mstate.dtms_difo = NULL;
5872 mstate.dtms_probe = probe;
5873 mstate.dtms_strtok = NULL;
5874 mstate.dtms_arg[0] = arg0;
5875 mstate.dtms_arg[1] = arg1;
5876 mstate.dtms_arg[2] = arg2;
5877 mstate.dtms_arg[3] = arg3;
5878 mstate.dtms_arg[4] = arg4;
5879
5880 flags = (volatile uint16_t *)&cpu_core[cpuid].cpuc_dtrace_flags;
5881
5882 for (ecb = probe->dtpr_ecb; ecb != NULL; ecb = ecb->dte_next) {
5883 dtrace_predicate_t *pred = ecb->dte_predicate;
5884 dtrace_state_t *state = ecb->dte_state;
5885 dtrace_buffer_t *buf = &state->dts_buffer[cpuid];
5886 dtrace_buffer_t *aggbuf = &state->dts_aggbuffer[cpuid];
5887 dtrace_vstate_t *vstate = &state->dts_vstate;
5888 dtrace_provider_t *prov = probe->dtpr_provider;
5889 uint64_t tracememsize = 0;
5890 int committed = 0;
5891 caddr_t tomax;
5892
5893 /*
5894 * A little subtlety with the following (seemingly innocuous)
5895 * declaration of the automatic 'val': by looking at the
5896 * code, you might think that it could be declared in the
5897 * action processing loop, below. (That is, it's only used in
5898 * the action processing loop.) However, it must be declared
5899 * out of that scope because in the case of DIF expression
5900 * arguments to aggregating actions, one iteration of the
5901 * action loop will use the last iteration's value.
5902 */
5903 #ifdef lint
5904 uint64_t val = 0;
5905 #else
5906 uint64_t val;
5907 #endif
5908
5909 mstate.dtms_present = DTRACE_MSTATE_ARGS | DTRACE_MSTATE_PROBE;
5910 mstate.dtms_access = DTRACE_ACCESS_ARGS | DTRACE_ACCESS_PROC;
5911 *flags &= ~CPU_DTRACE_ERROR;
5912
5913 if (prov == dtrace_provider) {
5914 /*
5915 * If dtrace itself is the provider of this probe,
5916 * we're only going to continue processing the ECB if
5917 * arg0 (the dtrace_state_t) is equal to the ECB's
5918 * creating state. (This prevents disjoint consumers
5919 * from seeing one another's metaprobes.)
5920 */
5921 if (arg0 != (uint64_t)(uintptr_t)state)
5922 continue;
5923 }
5924
5925 if (state->dts_activity != DTRACE_ACTIVITY_ACTIVE) {
5926 /*
5927 * We're not currently active. If our provider isn't
5928 * the dtrace pseudo provider, we're not interested.
5929 */
5930 if (prov != dtrace_provider)
5931 continue;
5932
5933 /*
5934 * Now we must further check if we are in the BEGIN
5935 * probe. If we are, we will only continue processing
5936 * if we're still in WARMUP -- if one BEGIN enabling
5937 * has invoked the exit() action, we don't want to
5938 * evaluate subsequent BEGIN enablings.
5939 */
5940 if (probe->dtpr_id == dtrace_probeid_begin &&
5941 state->dts_activity != DTRACE_ACTIVITY_WARMUP) {
5942 ASSERT(state->dts_activity ==
5943 DTRACE_ACTIVITY_DRAINING);
5944 continue;
5945 }
5946 }
5947
5948 if (ecb->dte_cond && !dtrace_priv_probe(state, &mstate, ecb))
5949 continue;
5950
5951 if (now - state->dts_alive > dtrace_deadman_timeout) {
5952 /*
5953 * We seem to be dead. Unless we (a) have kernel
5954 * destructive permissions (b) have expicitly enabled
5955 * destructive actions and (c) destructive actions have
5956 * not been disabled, we're going to transition into
5957 * the KILLED state, from which no further processing
5958 * on this state will be performed.
5959 */
5960 if (!dtrace_priv_kernel_destructive(state) ||
5961 !state->dts_cred.dcr_destructive ||
5962 dtrace_destructive_disallow) {
5963 void *activity = &state->dts_activity;
5964 dtrace_activity_t current;
5965
5966 do {
5967 current = state->dts_activity;
5968 } while (dtrace_cas32(activity, current,
5969 DTRACE_ACTIVITY_KILLED) != current);
5970
5971 continue;
5972 }
5973 }
5974
5975 if ((offs = dtrace_buffer_reserve(buf, ecb->dte_needed,
5976 ecb->dte_alignment, state, &mstate)) < 0)
5977 continue;
5978
5979 tomax = buf->dtb_tomax;
5980 ASSERT(tomax != NULL);
5981
5982 if (ecb->dte_size != 0)
5983 DTRACE_STORE(uint32_t, tomax, offs, ecb->dte_epid);
5984
5985 mstate.dtms_epid = ecb->dte_epid;
5986 mstate.dtms_present |= DTRACE_MSTATE_EPID;
5987
5988 if (state->dts_cred.dcr_visible & DTRACE_CRV_KERNEL)
5989 mstate.dtms_access |= DTRACE_ACCESS_KERNEL;
5990
5991 if (pred != NULL) {
5992 dtrace_difo_t *dp = pred->dtp_difo;
5993 int rval;
5994
5995 rval = dtrace_dif_emulate(dp, &mstate, vstate, state);
5996
5997 if (!(*flags & CPU_DTRACE_ERROR) && !rval) {
5998 dtrace_cacheid_t cid = probe->dtpr_predcache;
5999
6000 if (cid != DTRACE_CACHEIDNONE && !onintr) {
6001 /*
6002 * Update the predicate cache...
6003 */
6004 ASSERT(cid == pred->dtp_cacheid);
6005 curthread->t_predcache = cid;
6006 }
6007
6008 continue;
6009 }
6010 }
6011
6012 for (act = ecb->dte_action; !(*flags & CPU_DTRACE_ERROR) &&
6013 act != NULL; act = act->dta_next) {
6014 size_t valoffs;
6015 dtrace_difo_t *dp;
6016 dtrace_recdesc_t *rec = &act->dta_rec;
6017
6018 size = rec->dtrd_size;
6019 valoffs = offs + rec->dtrd_offset;
6020
6021 if (DTRACEACT_ISAGG(act->dta_kind)) {
6022 uint64_t v = 0xbad;
6023 dtrace_aggregation_t *agg;
6024
6025 agg = (dtrace_aggregation_t *)act;
6026
6027 if ((dp = act->dta_difo) != NULL)
6028 v = dtrace_dif_emulate(dp,
6029 &mstate, vstate, state);
6030
6031 if (*flags & CPU_DTRACE_ERROR)
6032 continue;
6033
6034 /*
6035 * Note that we always pass the expression
6036 * value from the previous iteration of the
6037 * action loop. This value will only be used
6038 * if there is an expression argument to the
6039 * aggregating action, denoted by the
6040 * dtag_hasarg field.
6041 */
6042 dtrace_aggregate(agg, buf,
6043 offs, aggbuf, v, val);
6044 continue;
6045 }
6046
6047 switch (act->dta_kind) {
6048 case DTRACEACT_STOP:
6049 if (dtrace_priv_proc_destructive(state,
6050 &mstate))
6051 dtrace_action_stop();
6052 continue;
6053
6054 case DTRACEACT_BREAKPOINT:
6055 if (dtrace_priv_kernel_destructive(state))
6056 dtrace_action_breakpoint(ecb);
6057 continue;
6058
6059 case DTRACEACT_PANIC:
6060 if (dtrace_priv_kernel_destructive(state))
6061 dtrace_action_panic(ecb);
6062 continue;
6063
6064 case DTRACEACT_STACK:
6065 if (!dtrace_priv_kernel(state))
6066 continue;
6067
6068 dtrace_getpcstack((pc_t *)(tomax + valoffs),
6069 size / sizeof (pc_t), probe->dtpr_aframes,
6070 DTRACE_ANCHORED(probe) ? NULL :
6071 (uint32_t *)arg0);
6072
6073 continue;
6074
6075 case DTRACEACT_JSTACK:
6076 case DTRACEACT_USTACK:
6077 if (!dtrace_priv_proc(state, &mstate))
6078 continue;
6079
6080 /*
6081 * See comment in DIF_VAR_PID.
6082 */
6083 if (DTRACE_ANCHORED(mstate.dtms_probe) &&
6084 CPU_ON_INTR(CPU)) {
6085 int depth = DTRACE_USTACK_NFRAMES(
6086 rec->dtrd_arg) + 1;
6087
6088 dtrace_bzero((void *)(tomax + valoffs),
6089 DTRACE_USTACK_STRSIZE(rec->dtrd_arg)
6090 + depth * sizeof (uint64_t));
6091
6092 continue;
6093 }
6094
6095 if (DTRACE_USTACK_STRSIZE(rec->dtrd_arg) != 0 &&
6096 curproc->p_dtrace_helpers != NULL) {
6097 /*
6098 * This is the slow path -- we have
6099 * allocated string space, and we're
6100 * getting the stack of a process that
6101 * has helpers. Call into a separate
6102 * routine to perform this processing.
6103 */
6104 dtrace_action_ustack(&mstate, state,
6105 (uint64_t *)(tomax + valoffs),
6106 rec->dtrd_arg);
6107 continue;
6108 }
6109
6110 /*
6111 * Clear the string space, since there's no
6112 * helper to do it for us.
6113 */
6114 if (DTRACE_USTACK_STRSIZE(rec->dtrd_arg) != 0) {
6115 int depth = DTRACE_USTACK_NFRAMES(
6116 rec->dtrd_arg);
6117 size_t strsize = DTRACE_USTACK_STRSIZE(
6118 rec->dtrd_arg);
6119 uint64_t *buf = (uint64_t *)(tomax +
6120 valoffs);
6121 void *strspace = &buf[depth + 1];
6122
6123 dtrace_bzero(strspace,
6124 MIN(depth, strsize));
6125 }
6126
6127 DTRACE_CPUFLAG_SET(CPU_DTRACE_NOFAULT);
6128 dtrace_getupcstack((uint64_t *)
6129 (tomax + valoffs),
6130 DTRACE_USTACK_NFRAMES(rec->dtrd_arg) + 1);
6131 DTRACE_CPUFLAG_CLEAR(CPU_DTRACE_NOFAULT);
6132 continue;
6133
6134 default:
6135 break;
6136 }
6137
6138 dp = act->dta_difo;
6139 ASSERT(dp != NULL);
6140
6141 val = dtrace_dif_emulate(dp, &mstate, vstate, state);
6142
6143 if (*flags & CPU_DTRACE_ERROR)
6144 continue;
6145
6146 switch (act->dta_kind) {
6147 case DTRACEACT_SPECULATE:
6148 ASSERT(buf == &state->dts_buffer[cpuid]);
6149 buf = dtrace_speculation_buffer(state,
6150 cpuid, val);
6151
6152 if (buf == NULL) {
6153 *flags |= CPU_DTRACE_DROP;
6154 continue;
6155 }
6156
6157 offs = dtrace_buffer_reserve(buf,
6158 ecb->dte_needed, ecb->dte_alignment,
6159 state, NULL);
6160
6161 if (offs < 0) {
6162 *flags |= CPU_DTRACE_DROP;
6163 continue;
6164 }
6165
6166 tomax = buf->dtb_tomax;
6167 ASSERT(tomax != NULL);
6168
6169 if (ecb->dte_size != 0)
6170 DTRACE_STORE(uint32_t, tomax, offs,
6171 ecb->dte_epid);
6172 continue;
6173
6174 case DTRACEACT_CHILL:
6175 if (dtrace_priv_kernel_destructive(state))
6176 dtrace_action_chill(&mstate, val);
6177 continue;
6178
6179 case DTRACEACT_RAISE:
6180 if (dtrace_priv_proc_destructive(state,
6181 &mstate))
6182 dtrace_action_raise(val);
6183 continue;
6184
6185 case DTRACEACT_COMMIT:
6186 ASSERT(!committed);
6187
6188 /*
6189 * We need to commit our buffer state.
6190 */
6191 if (ecb->dte_size)
6192 buf->dtb_offset = offs + ecb->dte_size;
6193 buf = &state->dts_buffer[cpuid];
6194 dtrace_speculation_commit(state, cpuid, val);
6195 committed = 1;
6196 continue;
6197
6198 case DTRACEACT_DISCARD:
6199 dtrace_speculation_discard(state, cpuid, val);
6200 continue;
6201
6202 case DTRACEACT_DIFEXPR:
6203 case DTRACEACT_LIBACT:
6204 case DTRACEACT_PRINTF:
6205 case DTRACEACT_PRINTA:
6206 case DTRACEACT_SYSTEM:
6207 case DTRACEACT_FREOPEN:
6208 case DTRACEACT_TRACEMEM:
6209 break;
6210
6211 case DTRACEACT_TRACEMEM_DYNSIZE:
6212 tracememsize = val;
6213 break;
6214
6215 case DTRACEACT_SYM:
6216 case DTRACEACT_MOD:
6217 if (!dtrace_priv_kernel(state))
6218 continue;
6219 break;
6220
6221 case DTRACEACT_USYM:
6222 case DTRACEACT_UMOD:
6223 case DTRACEACT_UADDR: {
6224 struct pid *pid = curthread->t_procp->p_pidp;
6225
6226 if (!dtrace_priv_proc(state, &mstate))
6227 continue;
6228
6229 DTRACE_STORE(uint64_t, tomax,
6230 valoffs, (uint64_t)pid->pid_id);
6231 DTRACE_STORE(uint64_t, tomax,
6232 valoffs + sizeof (uint64_t), val);
6233
6234 continue;
6235 }
6236
6237 case DTRACEACT_EXIT: {
6238 /*
6239 * For the exit action, we are going to attempt
6240 * to atomically set our activity to be
6241 * draining. If this fails (either because
6242 * another CPU has beat us to the exit action,
6243 * or because our current activity is something
6244 * other than ACTIVE or WARMUP), we will
6245 * continue. This assures that the exit action
6246 * can be successfully recorded at most once
6247 * when we're in the ACTIVE state. If we're
6248 * encountering the exit() action while in
6249 * COOLDOWN, however, we want to honor the new
6250 * status code. (We know that we're the only
6251 * thread in COOLDOWN, so there is no race.)
6252 */
6253 void *activity = &state->dts_activity;
6254 dtrace_activity_t current = state->dts_activity;
6255
6256 if (current == DTRACE_ACTIVITY_COOLDOWN)
6257 break;
6258
6259 if (current != DTRACE_ACTIVITY_WARMUP)
6260 current = DTRACE_ACTIVITY_ACTIVE;
6261
6262 if (dtrace_cas32(activity, current,
6263 DTRACE_ACTIVITY_DRAINING) != current) {
6264 *flags |= CPU_DTRACE_DROP;
6265 continue;
6266 }
6267
6268 break;
6269 }
6270
6271 default:
6272 ASSERT(0);
6273 }
6274
6275 if (dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF) {
6276 uintptr_t end = valoffs + size;
6277
6278 if (tracememsize != 0 &&
6279 valoffs + tracememsize < end) {
6280 end = valoffs + tracememsize;
6281 tracememsize = 0;
6282 }
6283
6284 if (!dtrace_vcanload((void *)(uintptr_t)val,
6285 &dp->dtdo_rtype, &mstate, vstate))
6286 continue;
6287
6288 /*
6289 * If this is a string, we're going to only
6290 * load until we find the zero byte -- after
6291 * which we'll store zero bytes.
6292 */
6293 if (dp->dtdo_rtype.dtdt_kind ==
6294 DIF_TYPE_STRING) {
6295 char c = '\0' + 1;
6296 int intuple = act->dta_intuple;
6297 size_t s;
6298
6299 for (s = 0; s < size; s++) {
6300 if (c != '\0')
6301 c = dtrace_load8(val++);
6302
6303 DTRACE_STORE(uint8_t, tomax,
6304 valoffs++, c);
6305
6306 if (c == '\0' && intuple)
6307 break;
6308 }
6309
6310 continue;
6311 }
6312
6313 while (valoffs < end) {
6314 DTRACE_STORE(uint8_t, tomax, valoffs++,
6315 dtrace_load8(val++));
6316 }
6317
6318 continue;
6319 }
6320
6321 switch (size) {
6322 case 0:
6323 break;
6324
6325 case sizeof (uint8_t):
6326 DTRACE_STORE(uint8_t, tomax, valoffs, val);
6327 break;
6328 case sizeof (uint16_t):
6329 DTRACE_STORE(uint16_t, tomax, valoffs, val);
6330 break;
6331 case sizeof (uint32_t):
6332 DTRACE_STORE(uint32_t, tomax, valoffs, val);
6333 break;
6334 case sizeof (uint64_t):
6335 DTRACE_STORE(uint64_t, tomax, valoffs, val);
6336 break;
6337 default:
6338 /*
6339 * Any other size should have been returned by
6340 * reference, not by value.
6341 */
6342 ASSERT(0);
6343 break;
6344 }
6345 }
6346
6347 if (*flags & CPU_DTRACE_DROP)
6348 continue;
6349
6350 if (*flags & CPU_DTRACE_FAULT) {
6351 int ndx;
6352 dtrace_action_t *err;
6353
6354 buf->dtb_errors++;
6355
6356 if (probe->dtpr_id == dtrace_probeid_error) {
6357 /*
6358 * There's nothing we can do -- we had an
6359 * error on the error probe. We bump an
6360 * error counter to at least indicate that
6361 * this condition happened.
6362 */
6363 dtrace_error(&state->dts_dblerrors);
6364 continue;
6365 }
6366
6367 if (vtime) {
6368 /*
6369 * Before recursing on dtrace_probe(), we
6370 * need to explicitly clear out our start
6371 * time to prevent it from being accumulated
6372 * into t_dtrace_vtime.
6373 */
6374 curthread->t_dtrace_start = 0;
6375 }
6376
6377 /*
6378 * Iterate over the actions to figure out which action
6379 * we were processing when we experienced the error.
6380 * Note that act points _past_ the faulting action; if
6381 * act is ecb->dte_action, the fault was in the
6382 * predicate, if it's ecb->dte_action->dta_next it's
6383 * in action #1, and so on.
6384 */
6385 for (err = ecb->dte_action, ndx = 0;
6386 err != act; err = err->dta_next, ndx++)
6387 continue;
6388
6389 dtrace_probe_error(state, ecb->dte_epid, ndx,
6390 (mstate.dtms_present & DTRACE_MSTATE_FLTOFFS) ?
6391 mstate.dtms_fltoffs : -1, DTRACE_FLAGS2FLT(*flags),
6392 cpu_core[cpuid].cpuc_dtrace_illval);
6393
6394 continue;
6395 }
6396
6397 if (!committed)
6398 buf->dtb_offset = offs + ecb->dte_size;
6399 }
6400
6401 if (vtime)
6402 curthread->t_dtrace_start = dtrace_gethrtime();
6403
6404 dtrace_interrupt_enable(cookie);
6405 }
6406
6407 /*
6408 * DTrace Probe Hashing Functions
6409 *
6410 * The functions in this section (and indeed, the functions in remaining
6411 * sections) are not _called_ from probe context. (Any exceptions to this are
6412 * marked with a "Note:".) Rather, they are called from elsewhere in the
6413 * DTrace framework to look-up probes in, add probes to and remove probes from
6414 * the DTrace probe hashes. (Each probe is hashed by each element of the
6415 * probe tuple -- allowing for fast lookups, regardless of what was
6416 * specified.)
6417 */
6418 static uint_t
6419 dtrace_hash_str(char *p)
6420 {
6421 unsigned int g;
6422 uint_t hval = 0;
6423
6424 while (*p) {
6425 hval = (hval << 4) + *p++;
6426 if ((g = (hval & 0xf0000000)) != 0)
6427 hval ^= g >> 24;
6428 hval &= ~g;
6429 }
6430 return (hval);
6431 }
6432
6433 static dtrace_hash_t *
6434 dtrace_hash_create(uintptr_t stroffs, uintptr_t nextoffs, uintptr_t prevoffs)
6435 {
6436 dtrace_hash_t *hash = kmem_zalloc(sizeof (dtrace_hash_t), KM_SLEEP);
6437
6438 hash->dth_stroffs = stroffs;
6439 hash->dth_nextoffs = nextoffs;
6440 hash->dth_prevoffs = prevoffs;
6441
6442 hash->dth_size = 1;
6443 hash->dth_mask = hash->dth_size - 1;
6444
6445 hash->dth_tab = kmem_zalloc(hash->dth_size *
6446 sizeof (dtrace_hashbucket_t *), KM_SLEEP);
6447
6448 return (hash);
6449 }
6450
6451 static void
6452 dtrace_hash_destroy(dtrace_hash_t *hash)
6453 {
6454 #ifdef DEBUG
6455 int i;
6456
6457 for (i = 0; i < hash->dth_size; i++)
6458 ASSERT(hash->dth_tab[i] == NULL);
6459 #endif
6460
6461 kmem_free(hash->dth_tab,
6462 hash->dth_size * sizeof (dtrace_hashbucket_t *));
6463 kmem_free(hash, sizeof (dtrace_hash_t));
6464 }
6465
6466 static void
6467 dtrace_hash_resize(dtrace_hash_t *hash)
6468 {
6469 int size = hash->dth_size, i, ndx;
6470 int new_size = hash->dth_size << 1;
6471 int new_mask = new_size - 1;
6472 dtrace_hashbucket_t **new_tab, *bucket, *next;
6473
6474 ASSERT((new_size & new_mask) == 0);
6475
6476 new_tab = kmem_zalloc(new_size * sizeof (void *), KM_SLEEP);
6477
6478 for (i = 0; i < size; i++) {
6479 for (bucket = hash->dth_tab[i]; bucket != NULL; bucket = next) {
6480 dtrace_probe_t *probe = bucket->dthb_chain;
6481
6482 ASSERT(probe != NULL);
6483 ndx = DTRACE_HASHSTR(hash, probe) & new_mask;
6484
6485 next = bucket->dthb_next;
6486 bucket->dthb_next = new_tab[ndx];
6487 new_tab[ndx] = bucket;
6488 }
6489 }
6490
6491 kmem_free(hash->dth_tab, hash->dth_size * sizeof (void *));
6492 hash->dth_tab = new_tab;
6493 hash->dth_size = new_size;
6494 hash->dth_mask = new_mask;
6495 }
6496
6497 static void
6498 dtrace_hash_add(dtrace_hash_t *hash, dtrace_probe_t *new)
6499 {
6500 int hashval = DTRACE_HASHSTR(hash, new);
6501 int ndx = hashval & hash->dth_mask;
6502 dtrace_hashbucket_t *bucket = hash->dth_tab[ndx];
6503 dtrace_probe_t **nextp, **prevp;
6504
6505 for (; bucket != NULL; bucket = bucket->dthb_next) {
6506 if (DTRACE_HASHEQ(hash, bucket->dthb_chain, new))
6507 goto add;
6508 }
6509
6510 if ((hash->dth_nbuckets >> 1) > hash->dth_size) {
6511 dtrace_hash_resize(hash);
6512 dtrace_hash_add(hash, new);
6513 return;
6514 }
6515
6516 bucket = kmem_zalloc(sizeof (dtrace_hashbucket_t), KM_SLEEP);
6517 bucket->dthb_next = hash->dth_tab[ndx];
6518 hash->dth_tab[ndx] = bucket;
6519 hash->dth_nbuckets++;
6520
6521 add:
6522 nextp = DTRACE_HASHNEXT(hash, new);
6523 ASSERT(*nextp == NULL && *(DTRACE_HASHPREV(hash, new)) == NULL);
6524 *nextp = bucket->dthb_chain;
6525
6526 if (bucket->dthb_chain != NULL) {
6527 prevp = DTRACE_HASHPREV(hash, bucket->dthb_chain);
6528 ASSERT(*prevp == NULL);
6529 *prevp = new;
6530 }
6531
6532 bucket->dthb_chain = new;
6533 bucket->dthb_len++;
6534 }
6535
6536 static dtrace_probe_t *
6537 dtrace_hash_lookup(dtrace_hash_t *hash, dtrace_probe_t *template)
6538 {
6539 int hashval = DTRACE_HASHSTR(hash, template);
6540 int ndx = hashval & hash->dth_mask;
6541 dtrace_hashbucket_t *bucket = hash->dth_tab[ndx];
6542
6543 for (; bucket != NULL; bucket = bucket->dthb_next) {
6544 if (DTRACE_HASHEQ(hash, bucket->dthb_chain, template))
6545 return (bucket->dthb_chain);
6546 }
6547
6548 return (NULL);
6549 }
6550
6551 static int
6552 dtrace_hash_collisions(dtrace_hash_t *hash, dtrace_probe_t *template)
6553 {
6554 int hashval = DTRACE_HASHSTR(hash, template);
6555 int ndx = hashval & hash->dth_mask;
6556 dtrace_hashbucket_t *bucket = hash->dth_tab[ndx];
6557
6558 for (; bucket != NULL; bucket = bucket->dthb_next) {
6559 if (DTRACE_HASHEQ(hash, bucket->dthb_chain, template))
6560 return (bucket->dthb_len);
6561 }
6562
6563 return (NULL);
6564 }
6565
6566 static void
6567 dtrace_hash_remove(dtrace_hash_t *hash, dtrace_probe_t *probe)
6568 {
6569 int ndx = DTRACE_HASHSTR(hash, probe) & hash->dth_mask;
6570 dtrace_hashbucket_t *bucket = hash->dth_tab[ndx];
6571
6572 dtrace_probe_t **prevp = DTRACE_HASHPREV(hash, probe);
6573 dtrace_probe_t **nextp = DTRACE_HASHNEXT(hash, probe);
6574
6575 /*
6576 * Find the bucket that we're removing this probe from.
6577 */
6578 for (; bucket != NULL; bucket = bucket->dthb_next) {
6579 if (DTRACE_HASHEQ(hash, bucket->dthb_chain, probe))
6580 break;
6581 }
6582
6583 ASSERT(bucket != NULL);
6584
6585 if (*prevp == NULL) {
6586 if (*nextp == NULL) {
6587 /*
6588 * The removed probe was the only probe on this
6589 * bucket; we need to remove the bucket.
6590 */
6591 dtrace_hashbucket_t *b = hash->dth_tab[ndx];
6592
6593 ASSERT(bucket->dthb_chain == probe);
6594 ASSERT(b != NULL);
6595
6596 if (b == bucket) {
6597 hash->dth_tab[ndx] = bucket->dthb_next;
6598 } else {
6599 while (b->dthb_next != bucket)
6600 b = b->dthb_next;
6601 b->dthb_next = bucket->dthb_next;
6602 }
6603
6604 ASSERT(hash->dth_nbuckets > 0);
6605 hash->dth_nbuckets--;
6606 kmem_free(bucket, sizeof (dtrace_hashbucket_t));
6607 return;
6608 }
6609
6610 bucket->dthb_chain = *nextp;
6611 } else {
6612 *(DTRACE_HASHNEXT(hash, *prevp)) = *nextp;
6613 }
6614
6615 if (*nextp != NULL)
6616 *(DTRACE_HASHPREV(hash, *nextp)) = *prevp;
6617 }
6618
6619 /*
6620 * DTrace Utility Functions
6621 *
6622 * These are random utility functions that are _not_ called from probe context.
6623 */
6624 static int
6625 dtrace_badattr(const dtrace_attribute_t *a)
6626 {
6627 return (a->dtat_name > DTRACE_STABILITY_MAX ||
6628 a->dtat_data > DTRACE_STABILITY_MAX ||
6629 a->dtat_class > DTRACE_CLASS_MAX);
6630 }
6631
6632 /*
6633 * Return a duplicate copy of a string. If the specified string is NULL,
6634 * this function returns a zero-length string.
6635 */
6636 static char *
6637 dtrace_strdup(const char *str)
6638 {
6639 char *new = kmem_zalloc((str != NULL ? strlen(str) : 0) + 1, KM_SLEEP);
6640
6641 if (str != NULL)
6642 (void) strcpy(new, str);
6643
6644 return (new);
6645 }
6646
6647 #define DTRACE_ISALPHA(c) \
6648 (((c) >= 'a' && (c) <= 'z') || ((c) >= 'A' && (c) <= 'Z'))
6649
6650 static int
6651 dtrace_badname(const char *s)
6652 {
6653 char c;
6654
6655 if (s == NULL || (c = *s++) == '\0')
6656 return (0);
6657
6658 if (!DTRACE_ISALPHA(c) && c != '-' && c != '_' && c != '.')
6659 return (1);
6660
6661 while ((c = *s++) != '\0') {
6662 if (!DTRACE_ISALPHA(c) && (c < '0' || c > '9') &&
6663 c != '-' && c != '_' && c != '.' && c != '`')
6664 return (1);
6665 }
6666
6667 return (0);
6668 }
6669
6670 static void
6671 dtrace_cred2priv(cred_t *cr, uint32_t *privp, uid_t *uidp, zoneid_t *zoneidp)
6672 {
6673 uint32_t priv;
6674
6675 if (cr == NULL || PRIV_POLICY_ONLY(cr, PRIV_ALL, B_FALSE)) {
6676 /*
6677 * For DTRACE_PRIV_ALL, the uid and zoneid don't matter.
6678 */
6679 priv = DTRACE_PRIV_ALL;
6680 } else {
6681 *uidp = crgetuid(cr);
6682 *zoneidp = crgetzoneid(cr);
6683
6684 priv = 0;
6685 if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_KERNEL, B_FALSE))
6686 priv |= DTRACE_PRIV_KERNEL | DTRACE_PRIV_USER;
6687 else if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_USER, B_FALSE))
6688 priv |= DTRACE_PRIV_USER;
6689 if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_PROC, B_FALSE))
6690 priv |= DTRACE_PRIV_PROC;
6691 if (PRIV_POLICY_ONLY(cr, PRIV_PROC_OWNER, B_FALSE))
6692 priv |= DTRACE_PRIV_OWNER;
6693 if (PRIV_POLICY_ONLY(cr, PRIV_PROC_ZONE, B_FALSE))
6694 priv |= DTRACE_PRIV_ZONEOWNER;
6695 }
6696
6697 *privp = priv;
6698 }
6699
6700 #ifdef DTRACE_ERRDEBUG
6701 static void
6702 dtrace_errdebug(const char *str)
6703 {
6704 int hval = dtrace_hash_str((char *)str) % DTRACE_ERRHASHSZ;
6705 int occupied = 0;
6706
6707 mutex_enter(&dtrace_errlock);
6708 dtrace_errlast = str;
6709 dtrace_errthread = curthread;
6710
6711 while (occupied++ < DTRACE_ERRHASHSZ) {
6712 if (dtrace_errhash[hval].dter_msg == str) {
6713 dtrace_errhash[hval].dter_count++;
6714 goto out;
6715 }
6716
6717 if (dtrace_errhash[hval].dter_msg != NULL) {
6718 hval = (hval + 1) % DTRACE_ERRHASHSZ;
6719 continue;
6720 }
6721
6722 dtrace_errhash[hval].dter_msg = str;
6723 dtrace_errhash[hval].dter_count = 1;
6724 goto out;
6725 }
6726
6727 panic("dtrace: undersized error hash");
6728 out:
6729 mutex_exit(&dtrace_errlock);
6730 }
6731 #endif
6732
6733 /*
6734 * DTrace Matching Functions
6735 *
6736 * These functions are used to match groups of probes, given some elements of
6737 * a probe tuple, or some globbed expressions for elements of a probe tuple.
6738 */
6739 static int
6740 dtrace_match_priv(const dtrace_probe_t *prp, uint32_t priv, uid_t uid,
6741 zoneid_t zoneid)
6742 {
6743 if (priv != DTRACE_PRIV_ALL) {
6744 uint32_t ppriv = prp->dtpr_provider->dtpv_priv.dtpp_flags;
6745 uint32_t match = priv & ppriv;
6746
6747 /*
6748 * No PRIV_DTRACE_* privileges...
6749 */
6750 if ((priv & (DTRACE_PRIV_PROC | DTRACE_PRIV_USER |
6751 DTRACE_PRIV_KERNEL)) == 0)
6752 return (0);
6753
6754 /*
6755 * No matching bits, but there were bits to match...
6756 */
6757 if (match == 0 && ppriv != 0)
6758 return (0);
6759
6760 /*
6761 * Need to have permissions to the process, but don't...
6762 */
6763 if (((ppriv & ~match) & DTRACE_PRIV_OWNER) != 0 &&
6764 uid != prp->dtpr_provider->dtpv_priv.dtpp_uid) {
6765 return (0);
6766 }
6767
6768 /*
6769 * Need to be in the same zone unless we possess the
6770 * privilege to examine all zones.
6771 */
6772 if (((ppriv & ~match) & DTRACE_PRIV_ZONEOWNER) != 0 &&
6773 zoneid != prp->dtpr_provider->dtpv_priv.dtpp_zoneid) {
6774 return (0);
6775 }
6776 }
6777
6778 return (1);
6779 }
6780
6781 /*
6782 * dtrace_match_probe compares a dtrace_probe_t to a pre-compiled key, which
6783 * consists of input pattern strings and an ops-vector to evaluate them.
6784 * This function returns >0 for match, 0 for no match, and <0 for error.
6785 */
6786 static int
6787 dtrace_match_probe(const dtrace_probe_t *prp, const dtrace_probekey_t *pkp,
6788 uint32_t priv, uid_t uid, zoneid_t zoneid)
6789 {
6790 dtrace_provider_t *pvp = prp->dtpr_provider;
6791 int rv;
6792
6793 if (pvp->dtpv_defunct)
6794 return (0);
6795
6796 if ((rv = pkp->dtpk_pmatch(pvp->dtpv_name, pkp->dtpk_prov, 0)) <= 0)
6797 return (rv);
6798
6799 if ((rv = pkp->dtpk_mmatch(prp->dtpr_mod, pkp->dtpk_mod, 0)) <= 0)
6800 return (rv);
6801
6802 if ((rv = pkp->dtpk_fmatch(prp->dtpr_func, pkp->dtpk_func, 0)) <= 0)
6803 return (rv);
6804
6805 if ((rv = pkp->dtpk_nmatch(prp->dtpr_name, pkp->dtpk_name, 0)) <= 0)
6806 return (rv);
6807
6808 if (dtrace_match_priv(prp, priv, uid, zoneid) == 0)
6809 return (0);
6810
6811 return (rv);
6812 }
6813
6814 /*
6815 * dtrace_match_glob() is a safe kernel implementation of the gmatch(3GEN)
6816 * interface for matching a glob pattern 'p' to an input string 's'. Unlike
6817 * libc's version, the kernel version only applies to 8-bit ASCII strings.
6818 * In addition, all of the recursion cases except for '*' matching have been
6819 * unwound. For '*', we still implement recursive evaluation, but a depth
6820 * counter is maintained and matching is aborted if we recurse too deep.
6821 * The function returns 0 if no match, >0 if match, and <0 if recursion error.
6822 */
6823 static int
6824 dtrace_match_glob(const char *s, const char *p, int depth)
6825 {
6826 const char *olds;
6827 char s1, c;
6828 int gs;
6829
6830 if (depth > DTRACE_PROBEKEY_MAXDEPTH)
6831 return (-1);
6832
6833 if (s == NULL)
6834 s = ""; /* treat NULL as empty string */
6835
6836 top:
6837 olds = s;
6838 s1 = *s++;
6839
6840 if (p == NULL)
6841 return (0);
6842
6843 if ((c = *p++) == '\0')
6844 return (s1 == '\0');
6845
6846 switch (c) {
6847 case '[': {
6848 int ok = 0, notflag = 0;
6849 char lc = '\0';
6850
6851 if (s1 == '\0')
6852 return (0);
6853
6854 if (*p == '!') {
6855 notflag = 1;
6856 p++;
6857 }
6858
6859 if ((c = *p++) == '\0')
6860 return (0);
6861
6862 do {
6863 if (c == '-' && lc != '\0' && *p != ']') {
6864 if ((c = *p++) == '\0')
6865 return (0);
6866 if (c == '\\' && (c = *p++) == '\0')
6867 return (0);
6868
6869 if (notflag) {
6870 if (s1 < lc || s1 > c)
6871 ok++;
6872 else
6873 return (0);
6874 } else if (lc <= s1 && s1 <= c)
6875 ok++;
6876
6877 } else if (c == '\\' && (c = *p++) == '\0')
6878 return (0);
6879
6880 lc = c; /* save left-hand 'c' for next iteration */
6881
6882 if (notflag) {
6883 if (s1 != c)
6884 ok++;
6885 else
6886 return (0);
6887 } else if (s1 == c)
6888 ok++;
6889
6890 if ((c = *p++) == '\0')
6891 return (0);
6892
6893 } while (c != ']');
6894
6895 if (ok)
6896 goto top;
6897
6898 return (0);
6899 }
6900
6901 case '\\':
6902 if ((c = *p++) == '\0')
6903 return (0);
6904 /*FALLTHRU*/
6905
6906 default:
6907 if (c != s1)
6908 return (0);
6909 /*FALLTHRU*/
6910
6911 case '?':
6912 if (s1 != '\0')
6913 goto top;
6914 return (0);
6915
6916 case '*':
6917 while (*p == '*')
6918 p++; /* consecutive *'s are identical to a single one */
6919
6920 if (*p == '\0')
6921 return (1);
6922
6923 for (s = olds; *s != '\0'; s++) {
6924 if ((gs = dtrace_match_glob(s, p, depth + 1)) != 0)
6925 return (gs);
6926 }
6927
6928 return (0);
6929 }
6930 }
6931
6932 /*ARGSUSED*/
6933 static int
6934 dtrace_match_string(const char *s, const char *p, int depth)
6935 {
6936 return (s != NULL && strcmp(s, p) == 0);
6937 }
6938
6939 /*ARGSUSED*/
6940 static int
6941 dtrace_match_nul(const char *s, const char *p, int depth)
6942 {
6943 return (1); /* always match the empty pattern */
6944 }
6945
6946 /*ARGSUSED*/
6947 static int
6948 dtrace_match_nonzero(const char *s, const char *p, int depth)
6949 {
6950 return (s != NULL && s[0] != '\0');
6951 }
6952
6953 static int
6954 dtrace_match(const dtrace_probekey_t *pkp, uint32_t priv, uid_t uid,
6955 zoneid_t zoneid, int (*matched)(dtrace_probe_t *, void *), void *arg)
6956 {
6957 dtrace_probe_t template, *probe;
6958 dtrace_hash_t *hash = NULL;
6959 int len, rc, best = INT_MAX, nmatched = 0;
6960 dtrace_id_t i;
6961
6962 ASSERT(MUTEX_HELD(&dtrace_lock));
6963
6964 /*
6965 * If the probe ID is specified in the key, just lookup by ID and
6966 * invoke the match callback once if a matching probe is found.
6967 */
6968 if (pkp->dtpk_id != DTRACE_IDNONE) {
6969 if ((probe = dtrace_probe_lookup_id(pkp->dtpk_id)) != NULL &&
6970 dtrace_match_probe(probe, pkp, priv, uid, zoneid) > 0) {
6971 if ((*matched)(probe, arg) == DTRACE_MATCH_FAIL)
6972 return (DTRACE_MATCH_FAIL);
6973 nmatched++;
6974 }
6975 return (nmatched);
6976 }
6977
6978 template.dtpr_mod = (char *)pkp->dtpk_mod;
6979 template.dtpr_func = (char *)pkp->dtpk_func;
6980 template.dtpr_name = (char *)pkp->dtpk_name;
6981
6982 /*
6983 * We want to find the most distinct of the module name, function
6984 * name, and name. So for each one that is not a glob pattern or
6985 * empty string, we perform a lookup in the corresponding hash and
6986 * use the hash table with the fewest collisions to do our search.
6987 */
6988 if (pkp->dtpk_mmatch == &dtrace_match_string &&
6989 (len = dtrace_hash_collisions(dtrace_bymod, &template)) < best) {
6990 best = len;
6991 hash = dtrace_bymod;
6992 }
6993
6994 if (pkp->dtpk_fmatch == &dtrace_match_string &&
6995 (len = dtrace_hash_collisions(dtrace_byfunc, &template)) < best) {
6996 best = len;
6997 hash = dtrace_byfunc;
6998 }
6999
7000 if (pkp->dtpk_nmatch == &dtrace_match_string &&
7001 (len = dtrace_hash_collisions(dtrace_byname, &template)) < best) {
7002 best = len;
7003 hash = dtrace_byname;
7004 }
7005
7006 /*
7007 * If we did not select a hash table, iterate over every probe and
7008 * invoke our callback for each one that matches our input probe key.
7009 */
7010 if (hash == NULL) {
7011 for (i = 0; i < dtrace_nprobes; i++) {
7012 if ((probe = dtrace_probes[i]) == NULL ||
7013 dtrace_match_probe(probe, pkp, priv, uid,
7014 zoneid) <= 0)
7015 continue;
7016
7017 nmatched++;
7018
7019 if ((rc = (*matched)(probe, arg)) !=
7020 DTRACE_MATCH_NEXT) {
7021 if (rc == DTRACE_MATCH_FAIL)
7022 return (DTRACE_MATCH_FAIL);
7023 break;
7024 }
7025 }
7026
7027 return (nmatched);
7028 }
7029
7030 /*
7031 * If we selected a hash table, iterate over each probe of the same key
7032 * name and invoke the callback for every probe that matches the other
7033 * attributes of our input probe key.
7034 */
7035 for (probe = dtrace_hash_lookup(hash, &template); probe != NULL;
7036 probe = *(DTRACE_HASHNEXT(hash, probe))) {
7037
7038 if (dtrace_match_probe(probe, pkp, priv, uid, zoneid) <= 0)
7039 continue;
7040
7041 nmatched++;
7042
7043 if ((rc = (*matched)(probe, arg)) != DTRACE_MATCH_NEXT) {
7044 if (rc == DTRACE_MATCH_FAIL)
7045 return (DTRACE_MATCH_FAIL);
7046 break;
7047 }
7048 }
7049
7050 return (nmatched);
7051 }
7052
7053 /*
7054 * Return the function pointer dtrace_probecmp() should use to compare the
7055 * specified pattern with a string. For NULL or empty patterns, we select
7056 * dtrace_match_nul(). For glob pattern strings, we use dtrace_match_glob().
7057 * For non-empty non-glob strings, we use dtrace_match_string().
7058 */
7059 static dtrace_probekey_f *
7060 dtrace_probekey_func(const char *p)
7061 {
7062 char c;
7063
7064 if (p == NULL || *p == '\0')
7065 return (&dtrace_match_nul);
7066
7067 while ((c = *p++) != '\0') {
7068 if (c == '[' || c == '?' || c == '*' || c == '\\')
7069 return (&dtrace_match_glob);
7070 }
7071
7072 return (&dtrace_match_string);
7073 }
7074
7075 /*
7076 * Build a probe comparison key for use with dtrace_match_probe() from the
7077 * given probe description. By convention, a null key only matches anchored
7078 * probes: if each field is the empty string, reset dtpk_fmatch to
7079 * dtrace_match_nonzero().
7080 */
7081 static void
7082 dtrace_probekey(const dtrace_probedesc_t *pdp, dtrace_probekey_t *pkp)
7083 {
7084 pkp->dtpk_prov = pdp->dtpd_provider;
7085 pkp->dtpk_pmatch = dtrace_probekey_func(pdp->dtpd_provider);
7086
7087 pkp->dtpk_mod = pdp->dtpd_mod;
7088 pkp->dtpk_mmatch = dtrace_probekey_func(pdp->dtpd_mod);
7089
7090 pkp->dtpk_func = pdp->dtpd_func;
7091 pkp->dtpk_fmatch = dtrace_probekey_func(pdp->dtpd_func);
7092
7093 pkp->dtpk_name = pdp->dtpd_name;
7094 pkp->dtpk_nmatch = dtrace_probekey_func(pdp->dtpd_name);
7095
7096 pkp->dtpk_id = pdp->dtpd_id;
7097
7098 if (pkp->dtpk_id == DTRACE_IDNONE &&
7099 pkp->dtpk_pmatch == &dtrace_match_nul &&
7100 pkp->dtpk_mmatch == &dtrace_match_nul &&
7101 pkp->dtpk_fmatch == &dtrace_match_nul &&
7102 pkp->dtpk_nmatch == &dtrace_match_nul)
7103 pkp->dtpk_fmatch = &dtrace_match_nonzero;
7104 }
7105
7106 /*
7107 * DTrace Provider-to-Framework API Functions
7108 *
7109 * These functions implement much of the Provider-to-Framework API, as
7110 * described in <sys/dtrace.h>. The parts of the API not in this section are
7111 * the functions in the API for probe management (found below), and
7112 * dtrace_probe() itself (found above).
7113 */
7114
7115 /*
7116 * Register the calling provider with the DTrace framework. This should
7117 * generally be called by DTrace providers in their attach(9E) entry point.
7118 */
7119 int
7120 dtrace_register(const char *name, const dtrace_pattr_t *pap, uint32_t priv,
7121 cred_t *cr, const dtrace_pops_t *pops, void *arg, dtrace_provider_id_t *idp)
7122 {
7123 dtrace_provider_t *provider;
7124
7125 if (name == NULL || pap == NULL || pops == NULL || idp == NULL) {
7126 cmn_err(CE_WARN, "failed to register provider '%s': invalid "
7127 "arguments", name ? name : "<NULL>");
7128 return (EINVAL);
7129 }
7130
7131 if (name[0] == '\0' || dtrace_badname(name)) {
7132 cmn_err(CE_WARN, "failed to register provider '%s': invalid "
7133 "provider name", name);
7134 return (EINVAL);
7135 }
7136
7137 if ((pops->dtps_provide == NULL && pops->dtps_provide_module == NULL) ||
7138 pops->dtps_enable == NULL || pops->dtps_disable == NULL ||
7139 pops->dtps_destroy == NULL ||
7140 ((pops->dtps_resume == NULL) != (pops->dtps_suspend == NULL))) {
7141 cmn_err(CE_WARN, "failed to register provider '%s': invalid "
7142 "provider ops", name);
7143 return (EINVAL);
7144 }
7145
7146 if (dtrace_badattr(&pap->dtpa_provider) ||
7147 dtrace_badattr(&pap->dtpa_mod) ||
7148 dtrace_badattr(&pap->dtpa_func) ||
7149 dtrace_badattr(&pap->dtpa_name) ||
7150 dtrace_badattr(&pap->dtpa_args)) {
7151 cmn_err(CE_WARN, "failed to register provider '%s': invalid "
7152 "provider attributes", name);
7153 return (EINVAL);
7154 }
7155
7156 if (priv & ~DTRACE_PRIV_ALL) {
7157 cmn_err(CE_WARN, "failed to register provider '%s': invalid "
7158 "privilege attributes", name);
7159 return (EINVAL);
7160 }
7161
7162 if ((priv & DTRACE_PRIV_KERNEL) &&
7163 (priv & (DTRACE_PRIV_USER | DTRACE_PRIV_OWNER)) &&
7164 pops->dtps_mode == NULL) {
7165 cmn_err(CE_WARN, "failed to register provider '%s': need "
7166 "dtps_mode() op for given privilege attributes", name);
7167 return (EINVAL);
7168 }
7169
7170 provider = kmem_zalloc(sizeof (dtrace_provider_t), KM_SLEEP);
7171 provider->dtpv_name = kmem_alloc(strlen(name) + 1, KM_SLEEP);
7172 (void) strcpy(provider->dtpv_name, name);
7173
7174 provider->dtpv_attr = *pap;
7175 provider->dtpv_priv.dtpp_flags = priv;
7176 if (cr != NULL) {
7177 provider->dtpv_priv.dtpp_uid = crgetuid(cr);
7178 provider->dtpv_priv.dtpp_zoneid = crgetzoneid(cr);
7179 }
7180 provider->dtpv_pops = *pops;
7181
7182 if (pops->dtps_provide == NULL) {
7183 ASSERT(pops->dtps_provide_module != NULL);
7184 provider->dtpv_pops.dtps_provide =
7185 (void (*)(void *, const dtrace_probedesc_t *))dtrace_nullop;
7186 }
7187
7188 if (pops->dtps_provide_module == NULL) {
7189 ASSERT(pops->dtps_provide != NULL);
7190 provider->dtpv_pops.dtps_provide_module =
7191 (void (*)(void *, struct modctl *))dtrace_nullop;
7192 }
7193
7194 if (pops->dtps_suspend == NULL) {
7195 ASSERT(pops->dtps_resume == NULL);
7196 provider->dtpv_pops.dtps_suspend =
7197 (void (*)(void *, dtrace_id_t, void *))dtrace_nullop;
7198 provider->dtpv_pops.dtps_resume =
7199 (void (*)(void *, dtrace_id_t, void *))dtrace_nullop;
7200 }
7201
7202 provider->dtpv_arg = arg;
7203 *idp = (dtrace_provider_id_t)provider;
7204
7205 if (pops == &dtrace_provider_ops) {
7206 ASSERT(MUTEX_HELD(&dtrace_provider_lock));
7207 ASSERT(MUTEX_HELD(&dtrace_lock));
7208 ASSERT(dtrace_anon.dta_enabling == NULL);
7209
7210 /*
7211 * We make sure that the DTrace provider is at the head of
7212 * the provider chain.
7213 */
7214 provider->dtpv_next = dtrace_provider;
7215 dtrace_provider = provider;
7216 return (0);
7217 }
7218
7219 mutex_enter(&dtrace_provider_lock);
7220 mutex_enter(&dtrace_lock);
7221
7222 /*
7223 * If there is at least one provider registered, we'll add this
7224 * provider after the first provider.
7225 */
7226 if (dtrace_provider != NULL) {
7227 provider->dtpv_next = dtrace_provider->dtpv_next;
7228 dtrace_provider->dtpv_next = provider;
7229 } else {
7230 dtrace_provider = provider;
7231 }
7232
7233 if (dtrace_retained != NULL) {
7234 dtrace_enabling_provide(provider);
7235
7236 /*
7237 * Now we need to call dtrace_enabling_matchall() -- which
7238 * will acquire cpu_lock and dtrace_lock. We therefore need
7239 * to drop all of our locks before calling into it...
7240 */
7241 mutex_exit(&dtrace_lock);
7242 mutex_exit(&dtrace_provider_lock);
7243 dtrace_enabling_matchall();
7244
7245 return (0);
7246 }
7247
7248 mutex_exit(&dtrace_lock);
7249 mutex_exit(&dtrace_provider_lock);
7250
7251 return (0);
7252 }
7253
7254 /*
7255 * Unregister the specified provider from the DTrace framework. This should
7256 * generally be called by DTrace providers in their detach(9E) entry point.
7257 */
7258 int
7259 dtrace_unregister(dtrace_provider_id_t id)
7260 {
7261 dtrace_provider_t *old = (dtrace_provider_t *)id;
7262 dtrace_provider_t *prev = NULL;
7263 int i, self = 0, noreap = 0;
7264 dtrace_probe_t *probe, *first = NULL;
7265
7266 if (old->dtpv_pops.dtps_enable ==
7267 (int (*)(void *, dtrace_id_t, void *))dtrace_enable_nullop) {
7268 /*
7269 * If DTrace itself is the provider, we're called with locks
7270 * already held.
7271 */
7272 ASSERT(old == dtrace_provider);
7273 ASSERT(dtrace_devi != NULL);
7274 ASSERT(MUTEX_HELD(&dtrace_provider_lock));
7275 ASSERT(MUTEX_HELD(&dtrace_lock));
7276 self = 1;
7277
7278 if (dtrace_provider->dtpv_next != NULL) {
7279 /*
7280 * There's another provider here; return failure.
7281 */
7282 return (EBUSY);
7283 }
7284 } else {
7285 mutex_enter(&dtrace_provider_lock);
7286 mutex_enter(&mod_lock);
7287 mutex_enter(&dtrace_lock);
7288 }
7289
7290 /*
7291 * If anyone has /dev/dtrace open, or if there are anonymous enabled
7292 * probes, we refuse to let providers slither away, unless this
7293 * provider has already been explicitly invalidated.
7294 */
7295 if (!old->dtpv_defunct &&
7296 (dtrace_opens || (dtrace_anon.dta_state != NULL &&
7297 dtrace_anon.dta_state->dts_necbs > 0))) {
7298 if (!self) {
7299 mutex_exit(&dtrace_lock);
7300 mutex_exit(&mod_lock);
7301 mutex_exit(&dtrace_provider_lock);
7302 }
7303 return (EBUSY);
7304 }
7305
7306 /*
7307 * Attempt to destroy the probes associated with this provider.
7308 */
7309 for (i = 0; i < dtrace_nprobes; i++) {
7310 if ((probe = dtrace_probes[i]) == NULL)
7311 continue;
7312
7313 if (probe->dtpr_provider != old)
7314 continue;
7315
7316 if (probe->dtpr_ecb == NULL)
7317 continue;
7318
7319 /*
7320 * If we are trying to unregister a defunct provider, and the
7321 * provider was made defunct within the interval dictated by
7322 * dtrace_unregister_defunct_reap, we'll (asynchronously)
7323 * attempt to reap our enablings. To denote that the provider
7324 * should reattempt to unregister itself at some point in the
7325 * future, we will return a differentiable error code (EAGAIN
7326 * instead of EBUSY) in this case.
7327 */
7328 if (dtrace_gethrtime() - old->dtpv_defunct >
7329 dtrace_unregister_defunct_reap)
7330 noreap = 1;
7331
7332 if (!self) {
7333 mutex_exit(&dtrace_lock);
7334 mutex_exit(&mod_lock);
7335 mutex_exit(&dtrace_provider_lock);
7336 }
7337
7338 if (noreap)
7339 return (EBUSY);
7340
7341 (void) taskq_dispatch(dtrace_taskq,
7342 (task_func_t *)dtrace_enabling_reap, NULL, TQ_SLEEP);
7343
7344 return (EAGAIN);
7345 }
7346
7347 /*
7348 * All of the probes for this provider are disabled; we can safely
7349 * remove all of them from their hash chains and from the probe array.
7350 */
7351 for (i = 0; i < dtrace_nprobes; i++) {
7352 if ((probe = dtrace_probes[i]) == NULL)
7353 continue;
7354
7355 if (probe->dtpr_provider != old)
7356 continue;
7357
7358 dtrace_probes[i] = NULL;
7359
7360 dtrace_hash_remove(dtrace_bymod, probe);
7361 dtrace_hash_remove(dtrace_byfunc, probe);
7362 dtrace_hash_remove(dtrace_byname, probe);
7363
7364 if (first == NULL) {
7365 first = probe;
7366 probe->dtpr_nextmod = NULL;
7367 } else {
7368 probe->dtpr_nextmod = first;
7369 first = probe;
7370 }
7371 }
7372
7373 /*
7374 * The provider's probes have been removed from the hash chains and
7375 * from the probe array. Now issue a dtrace_sync() to be sure that
7376 * everyone has cleared out from any probe array processing.
7377 */
7378 dtrace_sync();
7379
7380 for (probe = first; probe != NULL; probe = first) {
7381 first = probe->dtpr_nextmod;
7382
7383 old->dtpv_pops.dtps_destroy(old->dtpv_arg, probe->dtpr_id,
7384 probe->dtpr_arg);
7385 kmem_free(probe->dtpr_mod, strlen(probe->dtpr_mod) + 1);
7386 kmem_free(probe->dtpr_func, strlen(probe->dtpr_func) + 1);
7387 kmem_free(probe->dtpr_name, strlen(probe->dtpr_name) + 1);
7388 vmem_free(dtrace_arena, (void *)(uintptr_t)(probe->dtpr_id), 1);
7389 kmem_free(probe, sizeof (dtrace_probe_t));
7390 }
7391
7392 if ((prev = dtrace_provider) == old) {
7393 ASSERT(self || dtrace_devi == NULL);
7394 ASSERT(old->dtpv_next == NULL || dtrace_devi == NULL);
7395 dtrace_provider = old->dtpv_next;
7396 } else {
7397 while (prev != NULL && prev->dtpv_next != old)
7398 prev = prev->dtpv_next;
7399
7400 if (prev == NULL) {
7401 panic("attempt to unregister non-existent "
7402 "dtrace provider %p\n", (void *)id);
7403 }
7404
7405 prev->dtpv_next = old->dtpv_next;
7406 }
7407
7408 if (!self) {
7409 mutex_exit(&dtrace_lock);
7410 mutex_exit(&mod_lock);
7411 mutex_exit(&dtrace_provider_lock);
7412 }
7413
7414 kmem_free(old->dtpv_name, strlen(old->dtpv_name) + 1);
7415 kmem_free(old, sizeof (dtrace_provider_t));
7416
7417 return (0);
7418 }
7419
7420 /*
7421 * Invalidate the specified provider. All subsequent probe lookups for the
7422 * specified provider will fail, but its probes will not be removed.
7423 */
7424 void
7425 dtrace_invalidate(dtrace_provider_id_t id)
7426 {
7427 dtrace_provider_t *pvp = (dtrace_provider_t *)id;
7428
7429 ASSERT(pvp->dtpv_pops.dtps_enable !=
7430 (int (*)(void *, dtrace_id_t, void *))dtrace_enable_nullop);
7431
7432 mutex_enter(&dtrace_provider_lock);
7433 mutex_enter(&dtrace_lock);
7434
7435 pvp->dtpv_defunct = dtrace_gethrtime();
7436
7437 mutex_exit(&dtrace_lock);
7438 mutex_exit(&dtrace_provider_lock);
7439 }
7440
7441 /*
7442 * Indicate whether or not DTrace has attached.
7443 */
7444 int
7445 dtrace_attached(void)
7446 {
7447 /*
7448 * dtrace_provider will be non-NULL iff the DTrace driver has
7449 * attached. (It's non-NULL because DTrace is always itself a
7450 * provider.)
7451 */
7452 return (dtrace_provider != NULL);
7453 }
7454
7455 /*
7456 * Remove all the unenabled probes for the given provider. This function is
7457 * not unlike dtrace_unregister(), except that it doesn't remove the provider
7458 * -- just as many of its associated probes as it can.
7459 */
7460 int
7461 dtrace_condense(dtrace_provider_id_t id)
7462 {
7463 dtrace_provider_t *prov = (dtrace_provider_t *)id;
7464 int i;
7465 dtrace_probe_t *probe;
7466
7467 /*
7468 * Make sure this isn't the dtrace provider itself.
7469 */
7470 ASSERT(prov->dtpv_pops.dtps_enable !=
7471 (int (*)(void *, dtrace_id_t, void *))dtrace_enable_nullop);
7472
7473 mutex_enter(&dtrace_provider_lock);
7474 mutex_enter(&dtrace_lock);
7475
7476 /*
7477 * Attempt to destroy the probes associated with this provider.
7478 */
7479 for (i = 0; i < dtrace_nprobes; i++) {
7480 if ((probe = dtrace_probes[i]) == NULL)
7481 continue;
7482
7483 if (probe->dtpr_provider != prov)
7484 continue;
7485
7486 if (probe->dtpr_ecb != NULL)
7487 continue;
7488
7489 dtrace_probes[i] = NULL;
7490
7491 dtrace_hash_remove(dtrace_bymod, probe);
7492 dtrace_hash_remove(dtrace_byfunc, probe);
7493 dtrace_hash_remove(dtrace_byname, probe);
7494
7495 prov->dtpv_pops.dtps_destroy(prov->dtpv_arg, i + 1,
7496 probe->dtpr_arg);
7497 kmem_free(probe->dtpr_mod, strlen(probe->dtpr_mod) + 1);
7498 kmem_free(probe->dtpr_func, strlen(probe->dtpr_func) + 1);
7499 kmem_free(probe->dtpr_name, strlen(probe->dtpr_name) + 1);
7500 kmem_free(probe, sizeof (dtrace_probe_t));
7501 vmem_free(dtrace_arena, (void *)((uintptr_t)i + 1), 1);
7502 }
7503
7504 mutex_exit(&dtrace_lock);
7505 mutex_exit(&dtrace_provider_lock);
7506
7507 return (0);
7508 }
7509
7510 /*
7511 * DTrace Probe Management Functions
7512 *
7513 * The functions in this section perform the DTrace probe management,
7514 * including functions to create probes, look-up probes, and call into the
7515 * providers to request that probes be provided. Some of these functions are
7516 * in the Provider-to-Framework API; these functions can be identified by the
7517 * fact that they are not declared "static".
7518 */
7519
7520 /*
7521 * Create a probe with the specified module name, function name, and name.
7522 */
7523 dtrace_id_t
7524 dtrace_probe_create(dtrace_provider_id_t prov, const char *mod,
7525 const char *func, const char *name, int aframes, void *arg)
7526 {
7527 dtrace_probe_t *probe, **probes;
7528 dtrace_provider_t *provider = (dtrace_provider_t *)prov;
7529 dtrace_id_t id;
7530
7531 if (provider == dtrace_provider) {
7532 ASSERT(MUTEX_HELD(&dtrace_lock));
7533 } else {
7534 mutex_enter(&dtrace_lock);
7535 }
7536
7537 id = (dtrace_id_t)(uintptr_t)vmem_alloc(dtrace_arena, 1,
7538 VM_BESTFIT | VM_SLEEP);
7539 probe = kmem_zalloc(sizeof (dtrace_probe_t), KM_SLEEP);
7540
7541 probe->dtpr_id = id;
7542 probe->dtpr_gen = dtrace_probegen++;
7543 probe->dtpr_mod = dtrace_strdup(mod);
7544 probe->dtpr_func = dtrace_strdup(func);
7545 probe->dtpr_name = dtrace_strdup(name);
7546 probe->dtpr_arg = arg;
7547 probe->dtpr_aframes = aframes;
7548 probe->dtpr_provider = provider;
7549
7550 dtrace_hash_add(dtrace_bymod, probe);
7551 dtrace_hash_add(dtrace_byfunc, probe);
7552 dtrace_hash_add(dtrace_byname, probe);
7553
7554 if (id - 1 >= dtrace_nprobes) {
7555 size_t osize = dtrace_nprobes * sizeof (dtrace_probe_t *);
7556 size_t nsize = osize << 1;
7557
7558 if (nsize == 0) {
7559 ASSERT(osize == 0);
7560 ASSERT(dtrace_probes == NULL);
7561 nsize = sizeof (dtrace_probe_t *);
7562 }
7563
7564 probes = kmem_zalloc(nsize, KM_SLEEP);
7565
7566 if (dtrace_probes == NULL) {
7567 ASSERT(osize == 0);
7568 dtrace_probes = probes;
7569 dtrace_nprobes = 1;
7570 } else {
7571 dtrace_probe_t **oprobes = dtrace_probes;
7572
7573 bcopy(oprobes, probes, osize);
7574 dtrace_membar_producer();
7575 dtrace_probes = probes;
7576
7577 dtrace_sync();
7578
7579 /*
7580 * All CPUs are now seeing the new probes array; we can
7581 * safely free the old array.
7582 */
7583 kmem_free(oprobes, osize);
7584 dtrace_nprobes <<= 1;
7585 }
7586
7587 ASSERT(id - 1 < dtrace_nprobes);
7588 }
7589
7590 ASSERT(dtrace_probes[id - 1] == NULL);
7591 dtrace_probes[id - 1] = probe;
7592
7593 if (provider != dtrace_provider)
7594 mutex_exit(&dtrace_lock);
7595
7596 return (id);
7597 }
7598
7599 static dtrace_probe_t *
7600 dtrace_probe_lookup_id(dtrace_id_t id)
7601 {
7602 ASSERT(MUTEX_HELD(&dtrace_lock));
7603
7604 if (id == 0 || id > dtrace_nprobes)
7605 return (NULL);
7606
7607 return (dtrace_probes[id - 1]);
7608 }
7609
7610 static int
7611 dtrace_probe_lookup_match(dtrace_probe_t *probe, void *arg)
7612 {
7613 *((dtrace_id_t *)arg) = probe->dtpr_id;
7614
7615 return (DTRACE_MATCH_DONE);
7616 }
7617
7618 /*
7619 * Look up a probe based on provider and one or more of module name, function
7620 * name and probe name.
7621 */
7622 dtrace_id_t
7623 dtrace_probe_lookup(dtrace_provider_id_t prid, const char *mod,
7624 const char *func, const char *name)
7625 {
7626 dtrace_probekey_t pkey;
7627 dtrace_id_t id;
7628 int match;
7629
7630 pkey.dtpk_prov = ((dtrace_provider_t *)prid)->dtpv_name;
7631 pkey.dtpk_pmatch = &dtrace_match_string;
7632 pkey.dtpk_mod = mod;
7633 pkey.dtpk_mmatch = mod ? &dtrace_match_string : &dtrace_match_nul;
7634 pkey.dtpk_func = func;
7635 pkey.dtpk_fmatch = func ? &dtrace_match_string : &dtrace_match_nul;
7636 pkey.dtpk_name = name;
7637 pkey.dtpk_nmatch = name ? &dtrace_match_string : &dtrace_match_nul;
7638 pkey.dtpk_id = DTRACE_IDNONE;
7639
7640 mutex_enter(&dtrace_lock);
7641 match = dtrace_match(&pkey, DTRACE_PRIV_ALL, 0, 0,
7642 dtrace_probe_lookup_match, &id);
7643 mutex_exit(&dtrace_lock);
7644
7645 ASSERT(match == 1 || match == 0);
7646 return (match ? id : 0);
7647 }
7648
7649 /*
7650 * Returns the probe argument associated with the specified probe.
7651 */
7652 void *
7653 dtrace_probe_arg(dtrace_provider_id_t id, dtrace_id_t pid)
7654 {
7655 dtrace_probe_t *probe;
7656 void *rval = NULL;
7657
7658 mutex_enter(&dtrace_lock);
7659
7660 if ((probe = dtrace_probe_lookup_id(pid)) != NULL &&
7661 probe->dtpr_provider == (dtrace_provider_t *)id)
7662 rval = probe->dtpr_arg;
7663
7664 mutex_exit(&dtrace_lock);
7665
7666 return (rval);
7667 }
7668
7669 /*
7670 * Copy a probe into a probe description.
7671 */
7672 static void
7673 dtrace_probe_description(const dtrace_probe_t *prp, dtrace_probedesc_t *pdp)
7674 {
7675 bzero(pdp, sizeof (dtrace_probedesc_t));
7676 pdp->dtpd_id = prp->dtpr_id;
7677
7678 (void) strncpy(pdp->dtpd_provider,
7679 prp->dtpr_provider->dtpv_name, DTRACE_PROVNAMELEN - 1);
7680
7681 (void) strncpy(pdp->dtpd_mod, prp->dtpr_mod, DTRACE_MODNAMELEN - 1);
7682 (void) strncpy(pdp->dtpd_func, prp->dtpr_func, DTRACE_FUNCNAMELEN - 1);
7683 (void) strncpy(pdp->dtpd_name, prp->dtpr_name, DTRACE_NAMELEN - 1);
7684 }
7685
7686 /*
7687 * Called to indicate that a probe -- or probes -- should be provided by a
7688 * specfied provider. If the specified description is NULL, the provider will
7689 * be told to provide all of its probes. (This is done whenever a new
7690 * consumer comes along, or whenever a retained enabling is to be matched.) If
7691 * the specified description is non-NULL, the provider is given the
7692 * opportunity to dynamically provide the specified probe, allowing providers
7693 * to support the creation of probes on-the-fly. (So-called _autocreated_
7694 * probes.) If the provider is NULL, the operations will be applied to all
7695 * providers; if the provider is non-NULL the operations will only be applied
7696 * to the specified provider. The dtrace_provider_lock must be held, and the
7697 * dtrace_lock must _not_ be held -- the provider's dtps_provide() operation
7698 * will need to grab the dtrace_lock when it reenters the framework through
7699 * dtrace_probe_lookup(), dtrace_probe_create(), etc.
7700 */
7701 static void
7702 dtrace_probe_provide(dtrace_probedesc_t *desc, dtrace_provider_t *prv)
7703 {
7704 struct modctl *ctl;
7705 int all = 0;
7706
7707 ASSERT(MUTEX_HELD(&dtrace_provider_lock));
7708
7709 if (prv == NULL) {
7710 all = 1;
7711 prv = dtrace_provider;
7712 }
7713
7714 do {
7715 /*
7716 * First, call the blanket provide operation.
7717 */
7718 prv->dtpv_pops.dtps_provide(prv->dtpv_arg, desc);
7719
7720 /*
7721 * Now call the per-module provide operation. We will grab
7722 * mod_lock to prevent the list from being modified. Note
7723 * that this also prevents the mod_busy bits from changing.
7724 * (mod_busy can only be changed with mod_lock held.)
7725 */
7726 mutex_enter(&mod_lock);
7727
7728 ctl = &modules;
7729 do {
7730 if (ctl->mod_busy || ctl->mod_mp == NULL)
7731 continue;
7732
7733 prv->dtpv_pops.dtps_provide_module(prv->dtpv_arg, ctl);
7734
7735 } while ((ctl = ctl->mod_next) != &modules);
7736
7737 mutex_exit(&mod_lock);
7738 } while (all && (prv = prv->dtpv_next) != NULL);
7739 }
7740
7741 /*
7742 * Iterate over each probe, and call the Framework-to-Provider API function
7743 * denoted by offs.
7744 */
7745 static void
7746 dtrace_probe_foreach(uintptr_t offs)
7747 {
7748 dtrace_provider_t *prov;
7749 void (*func)(void *, dtrace_id_t, void *);
7750 dtrace_probe_t *probe;
7751 dtrace_icookie_t cookie;
7752 int i;
7753
7754 /*
7755 * We disable interrupts to walk through the probe array. This is
7756 * safe -- the dtrace_sync() in dtrace_unregister() assures that we
7757 * won't see stale data.
7758 */
7759 cookie = dtrace_interrupt_disable();
7760
7761 for (i = 0; i < dtrace_nprobes; i++) {
7762 if ((probe = dtrace_probes[i]) == NULL)
7763 continue;
7764
7765 if (probe->dtpr_ecb == NULL) {
7766 /*
7767 * This probe isn't enabled -- don't call the function.
7768 */
7769 continue;
7770 }
7771
7772 prov = probe->dtpr_provider;
7773 func = *((void(**)(void *, dtrace_id_t, void *))
7774 ((uintptr_t)&prov->dtpv_pops + offs));
7775
7776 func(prov->dtpv_arg, i + 1, probe->dtpr_arg);
7777 }
7778
7779 dtrace_interrupt_enable(cookie);
7780 }
7781
7782 static int
7783 dtrace_probe_enable(const dtrace_probedesc_t *desc, dtrace_enabling_t *enab)
7784 {
7785 dtrace_probekey_t pkey;
7786 uint32_t priv;
7787 uid_t uid;
7788 zoneid_t zoneid;
7789
7790 ASSERT(MUTEX_HELD(&dtrace_lock));
7791 dtrace_ecb_create_cache = NULL;
7792
7793 if (desc == NULL) {
7794 /*
7795 * If we're passed a NULL description, we're being asked to
7796 * create an ECB with a NULL probe.
7797 */
7798 (void) dtrace_ecb_create_enable(NULL, enab);
7799 return (0);
7800 }
7801
7802 dtrace_probekey(desc, &pkey);
7803 dtrace_cred2priv(enab->dten_vstate->dtvs_state->dts_cred.dcr_cred,
7804 &priv, &uid, &zoneid);
7805
7806 return (dtrace_match(&pkey, priv, uid, zoneid, dtrace_ecb_create_enable,
7807 enab));
7808 }
7809
7810 /*
7811 * DTrace Helper Provider Functions
7812 */
7813 static void
7814 dtrace_dofattr2attr(dtrace_attribute_t *attr, const dof_attr_t dofattr)
7815 {
7816 attr->dtat_name = DOF_ATTR_NAME(dofattr);
7817 attr->dtat_data = DOF_ATTR_DATA(dofattr);
7818 attr->dtat_class = DOF_ATTR_CLASS(dofattr);
7819 }
7820
7821 static void
7822 dtrace_dofprov2hprov(dtrace_helper_provdesc_t *hprov,
7823 const dof_provider_t *dofprov, char *strtab)
7824 {
7825 hprov->dthpv_provname = strtab + dofprov->dofpv_name;
7826 dtrace_dofattr2attr(&hprov->dthpv_pattr.dtpa_provider,
7827 dofprov->dofpv_provattr);
7828 dtrace_dofattr2attr(&hprov->dthpv_pattr.dtpa_mod,
7829 dofprov->dofpv_modattr);
7830 dtrace_dofattr2attr(&hprov->dthpv_pattr.dtpa_func,
7831 dofprov->dofpv_funcattr);
7832 dtrace_dofattr2attr(&hprov->dthpv_pattr.dtpa_name,
7833 dofprov->dofpv_nameattr);
7834 dtrace_dofattr2attr(&hprov->dthpv_pattr.dtpa_args,
7835 dofprov->dofpv_argsattr);
7836 }
7837
7838 static void
7839 dtrace_helper_provide_one(dof_helper_t *dhp, dof_sec_t *sec, pid_t pid)
7840 {
7841 uintptr_t daddr = (uintptr_t)dhp->dofhp_dof;
7842 dof_hdr_t *dof = (dof_hdr_t *)daddr;
7843 dof_sec_t *str_sec, *prb_sec, *arg_sec, *off_sec, *enoff_sec;
7844 dof_provider_t *provider;
7845 dof_probe_t *probe;
7846 uint32_t *off, *enoff;
7847 uint8_t *arg;
7848 char *strtab;
7849 uint_t i, nprobes;
7850 dtrace_helper_provdesc_t dhpv;
7851 dtrace_helper_probedesc_t dhpb;
7852 dtrace_meta_t *meta = dtrace_meta_pid;
7853 dtrace_mops_t *mops = &meta->dtm_mops;
7854 void *parg;
7855
7856 provider = (dof_provider_t *)(uintptr_t)(daddr + sec->dofs_offset);
7857 str_sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff +
7858 provider->dofpv_strtab * dof->dofh_secsize);
7859 prb_sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff +
7860 provider->dofpv_probes * dof->dofh_secsize);
7861 arg_sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff +
7862 provider->dofpv_prargs * dof->dofh_secsize);
7863 off_sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff +
7864 provider->dofpv_proffs * dof->dofh_secsize);
7865
7866 strtab = (char *)(uintptr_t)(daddr + str_sec->dofs_offset);
7867 off = (uint32_t *)(uintptr_t)(daddr + off_sec->dofs_offset);
7868 arg = (uint8_t *)(uintptr_t)(daddr + arg_sec->dofs_offset);
7869 enoff = NULL;
7870
7871 /*
7872 * See dtrace_helper_provider_validate().
7873 */
7874 if (dof->dofh_ident[DOF_ID_VERSION] != DOF_VERSION_1 &&
7875 provider->dofpv_prenoffs != DOF_SECT_NONE) {
7876 enoff_sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff +
7877 provider->dofpv_prenoffs * dof->dofh_secsize);
7878 enoff = (uint32_t *)(uintptr_t)(daddr + enoff_sec->dofs_offset);
7879 }
7880
7881 nprobes = prb_sec->dofs_size / prb_sec->dofs_entsize;
7882
7883 /*
7884 * Create the provider.
7885 */
7886 dtrace_dofprov2hprov(&dhpv, provider, strtab);
7887
7888 if ((parg = mops->dtms_provide_pid(meta->dtm_arg, &dhpv, pid)) == NULL)
7889 return;
7890
7891 meta->dtm_count++;
7892
7893 /*
7894 * Create the probes.
7895 */
7896 for (i = 0; i < nprobes; i++) {
7897 probe = (dof_probe_t *)(uintptr_t)(daddr +
7898 prb_sec->dofs_offset + i * prb_sec->dofs_entsize);
7899
7900 dhpb.dthpb_mod = dhp->dofhp_mod;
7901 dhpb.dthpb_func = strtab + probe->dofpr_func;
7902 dhpb.dthpb_name = strtab + probe->dofpr_name;
7903 dhpb.dthpb_base = probe->dofpr_addr;
7904 dhpb.dthpb_offs = off + probe->dofpr_offidx;
7905 dhpb.dthpb_noffs = probe->dofpr_noffs;
7906 if (enoff != NULL) {
7907 dhpb.dthpb_enoffs = enoff + probe->dofpr_enoffidx;
7908 dhpb.dthpb_nenoffs = probe->dofpr_nenoffs;
7909 } else {
7910 dhpb.dthpb_enoffs = NULL;
7911 dhpb.dthpb_nenoffs = 0;
7912 }
7913 dhpb.dthpb_args = arg + probe->dofpr_argidx;
7914 dhpb.dthpb_nargc = probe->dofpr_nargc;
7915 dhpb.dthpb_xargc = probe->dofpr_xargc;
7916 dhpb.dthpb_ntypes = strtab + probe->dofpr_nargv;
7917 dhpb.dthpb_xtypes = strtab + probe->dofpr_xargv;
7918
7919 mops->dtms_create_probe(meta->dtm_arg, parg, &dhpb);
7920 }
7921 }
7922
7923 static void
7924 dtrace_helper_provide(dof_helper_t *dhp, pid_t pid)
7925 {
7926 uintptr_t daddr = (uintptr_t)dhp->dofhp_dof;
7927 dof_hdr_t *dof = (dof_hdr_t *)daddr;
7928 int i;
7929
7930 ASSERT(MUTEX_HELD(&dtrace_meta_lock));
7931
7932 for (i = 0; i < dof->dofh_secnum; i++) {
7933 dof_sec_t *sec = (dof_sec_t *)(uintptr_t)(daddr +
7934 dof->dofh_secoff + i * dof->dofh_secsize);
7935
7936 if (sec->dofs_type != DOF_SECT_PROVIDER)
7937 continue;
7938
7939 dtrace_helper_provide_one(dhp, sec, pid);
7940 }
7941
7942 /*
7943 * We may have just created probes, so we must now rematch against
7944 * any retained enablings. Note that this call will acquire both
7945 * cpu_lock and dtrace_lock; the fact that we are holding
7946 * dtrace_meta_lock now is what defines the ordering with respect to
7947 * these three locks.
7948 */
7949 dtrace_enabling_matchall();
7950 }
7951
7952 static void
7953 dtrace_helper_provider_remove_one(dof_helper_t *dhp, dof_sec_t *sec, pid_t pid)
7954 {
7955 uintptr_t daddr = (uintptr_t)dhp->dofhp_dof;
7956 dof_hdr_t *dof = (dof_hdr_t *)daddr;
7957 dof_sec_t *str_sec;
7958 dof_provider_t *provider;
7959 char *strtab;
7960 dtrace_helper_provdesc_t dhpv;
7961 dtrace_meta_t *meta = dtrace_meta_pid;
7962 dtrace_mops_t *mops = &meta->dtm_mops;
7963
7964 provider = (dof_provider_t *)(uintptr_t)(daddr + sec->dofs_offset);
7965 str_sec = (dof_sec_t *)(uintptr_t)(daddr + dof->dofh_secoff +
7966 provider->dofpv_strtab * dof->dofh_secsize);
7967
7968 strtab = (char *)(uintptr_t)(daddr + str_sec->dofs_offset);
7969
7970 /*
7971 * Create the provider.
7972 */
7973 dtrace_dofprov2hprov(&dhpv, provider, strtab);
7974
7975 mops->dtms_remove_pid(meta->dtm_arg, &dhpv, pid);
7976
7977 meta->dtm_count--;
7978 }
7979
7980 static void
7981 dtrace_helper_provider_remove(dof_helper_t *dhp, pid_t pid)
7982 {
7983 uintptr_t daddr = (uintptr_t)dhp->dofhp_dof;
7984 dof_hdr_t *dof = (dof_hdr_t *)daddr;
7985 int i;
7986
7987 ASSERT(MUTEX_HELD(&dtrace_meta_lock));
7988
7989 for (i = 0; i < dof->dofh_secnum; i++) {
7990 dof_sec_t *sec = (dof_sec_t *)(uintptr_t)(daddr +
7991 dof->dofh_secoff + i * dof->dofh_secsize);
7992
7993 if (sec->dofs_type != DOF_SECT_PROVIDER)
7994 continue;
7995
7996 dtrace_helper_provider_remove_one(dhp, sec, pid);
7997 }
7998 }
7999
8000 /*
8001 * DTrace Meta Provider-to-Framework API Functions
8002 *
8003 * These functions implement the Meta Provider-to-Framework API, as described
8004 * in <sys/dtrace.h>.
8005 */
8006 int
8007 dtrace_meta_register(const char *name, const dtrace_mops_t *mops, void *arg,
8008 dtrace_meta_provider_id_t *idp)
8009 {
8010 dtrace_meta_t *meta;
8011 dtrace_helpers_t *help, *next;
8012 int i;
8013
8014 *idp = DTRACE_METAPROVNONE;
8015
8016 /*
8017 * We strictly don't need the name, but we hold onto it for
8018 * debuggability. All hail error queues!
8019 */
8020 if (name == NULL) {
8021 cmn_err(CE_WARN, "failed to register meta-provider: "
8022 "invalid name");
8023 return (EINVAL);
8024 }
8025
8026 if (mops == NULL ||
8027 mops->dtms_create_probe == NULL ||
8028 mops->dtms_provide_pid == NULL ||
8029 mops->dtms_remove_pid == NULL) {
8030 cmn_err(CE_WARN, "failed to register meta-register %s: "
8031 "invalid ops", name);
8032 return (EINVAL);
8033 }
8034
8035 meta = kmem_zalloc(sizeof (dtrace_meta_t), KM_SLEEP);
8036 meta->dtm_mops = *mops;
8037 meta->dtm_name = kmem_alloc(strlen(name) + 1, KM_SLEEP);
8038 (void) strcpy(meta->dtm_name, name);
8039 meta->dtm_arg = arg;
8040
8041 mutex_enter(&dtrace_meta_lock);
8042 mutex_enter(&dtrace_lock);
8043
8044 if (dtrace_meta_pid != NULL) {
8045 mutex_exit(&dtrace_lock);
8046 mutex_exit(&dtrace_meta_lock);
8047 cmn_err(CE_WARN, "failed to register meta-register %s: "
8048 "user-land meta-provider exists", name);
8049 kmem_free(meta->dtm_name, strlen(meta->dtm_name) + 1);
8050 kmem_free(meta, sizeof (dtrace_meta_t));
8051 return (EINVAL);
8052 }
8053
8054 dtrace_meta_pid = meta;
8055 *idp = (dtrace_meta_provider_id_t)meta;
8056
8057 /*
8058 * If there are providers and probes ready to go, pass them
8059 * off to the new meta provider now.
8060 */
8061
8062 help = dtrace_deferred_pid;
8063 dtrace_deferred_pid = NULL;
8064
8065 mutex_exit(&dtrace_lock);
8066
8067 while (help != NULL) {
8068 for (i = 0; i < help->dthps_nprovs; i++) {
8069 dtrace_helper_provide(&help->dthps_provs[i]->dthp_prov,
8070 help->dthps_pid);
8071 }
8072
8073 next = help->dthps_next;
8074 help->dthps_next = NULL;
8075 help->dthps_prev = NULL;
8076 help->dthps_deferred = 0;
8077 help = next;
8078 }
8079
8080 mutex_exit(&dtrace_meta_lock);
8081
8082 return (0);
8083 }
8084
8085 int
8086 dtrace_meta_unregister(dtrace_meta_provider_id_t id)
8087 {
8088 dtrace_meta_t **pp, *old = (dtrace_meta_t *)id;
8089
8090 mutex_enter(&dtrace_meta_lock);
8091 mutex_enter(&dtrace_lock);
8092
8093 if (old == dtrace_meta_pid) {
8094 pp = &dtrace_meta_pid;
8095 } else {
8096 panic("attempt to unregister non-existent "
8097 "dtrace meta-provider %p\n", (void *)old);
8098 }
8099
8100 if (old->dtm_count != 0) {
8101 mutex_exit(&dtrace_lock);
8102 mutex_exit(&dtrace_meta_lock);
8103 return (EBUSY);
8104 }
8105
8106 *pp = NULL;
8107
8108 mutex_exit(&dtrace_lock);
8109 mutex_exit(&dtrace_meta_lock);
8110
8111 kmem_free(old->dtm_name, strlen(old->dtm_name) + 1);
8112 kmem_free(old, sizeof (dtrace_meta_t));
8113
8114 return (0);
8115 }
8116
8117
8118 /*
8119 * DTrace DIF Object Functions
8120 */
8121 static int
8122 dtrace_difo_err(uint_t pc, const char *format, ...)
8123 {
8124 if (dtrace_err_verbose) {
8125 va_list alist;
8126
8127 (void) uprintf("dtrace DIF object error: [%u]: ", pc);
8128 va_start(alist, format);
8129 (void) vuprintf(format, alist);
8130 va_end(alist);
8131 }
8132
8133 #ifdef DTRACE_ERRDEBUG
8134 dtrace_errdebug(format);
8135 #endif
8136 return (1);
8137 }
8138
8139 /*
8140 * Validate a DTrace DIF object by checking the IR instructions. The following
8141 * rules are currently enforced by dtrace_difo_validate():
8142 *
8143 * 1. Each instruction must have a valid opcode
8144 * 2. Each register, string, variable, or subroutine reference must be valid
8145 * 3. No instruction can modify register %r0 (must be zero)
8146 * 4. All instruction reserved bits must be set to zero
8147 * 5. The last instruction must be a "ret" instruction
8148 * 6. All branch targets must reference a valid instruction _after_ the branch
8149 */
8150 static int
8151 dtrace_difo_validate(dtrace_difo_t *dp, dtrace_vstate_t *vstate, uint_t nregs,
8152 cred_t *cr)
8153 {
8154 int err = 0, i;
8155 int (*efunc)(uint_t pc, const char *, ...) = dtrace_difo_err;
8156 int kcheckload;
8157 uint_t pc;
8158
8159 kcheckload = cr == NULL ||
8160 (vstate->dtvs_state->dts_cred.dcr_visible & DTRACE_CRV_KERNEL) == 0;
8161
8162 dp->dtdo_destructive = 0;
8163
8164 for (pc = 0; pc < dp->dtdo_len && err == 0; pc++) {
8165 dif_instr_t instr = dp->dtdo_buf[pc];
8166
8167 uint_t r1 = DIF_INSTR_R1(instr);
8168 uint_t r2 = DIF_INSTR_R2(instr);
8169 uint_t rd = DIF_INSTR_RD(instr);
8170 uint_t rs = DIF_INSTR_RS(instr);
8171 uint_t label = DIF_INSTR_LABEL(instr);
8172 uint_t v = DIF_INSTR_VAR(instr);
8173 uint_t subr = DIF_INSTR_SUBR(instr);
8174 uint_t type = DIF_INSTR_TYPE(instr);
8175 uint_t op = DIF_INSTR_OP(instr);
8176
8177 switch (op) {
8178 case DIF_OP_OR:
8179 case DIF_OP_XOR:
8180 case DIF_OP_AND:
8181 case DIF_OP_SLL:
8182 case DIF_OP_SRL:
8183 case DIF_OP_SRA:
8184 case DIF_OP_SUB:
8185 case DIF_OP_ADD:
8186 case DIF_OP_MUL:
8187 case DIF_OP_SDIV:
8188 case DIF_OP_UDIV:
8189 case DIF_OP_SREM:
8190 case DIF_OP_UREM:
8191 case DIF_OP_COPYS:
8192 if (r1 >= nregs)
8193 err += efunc(pc, "invalid register %u\n", r1);
8194 if (r2 >= nregs)
8195 err += efunc(pc, "invalid register %u\n", r2);
8196 if (rd >= nregs)
8197 err += efunc(pc, "invalid register %u\n", rd);
8198 if (rd == 0)
8199 err += efunc(pc, "cannot write to %r0\n");
8200 break;
8201 case DIF_OP_NOT:
8202 case DIF_OP_MOV:
8203 case DIF_OP_ALLOCS:
8204 if (r1 >= nregs)
8205 err += efunc(pc, "invalid register %u\n", r1);
8206 if (r2 != 0)
8207 err += efunc(pc, "non-zero reserved bits\n");
8208 if (rd >= nregs)
8209 err += efunc(pc, "invalid register %u\n", rd);
8210 if (rd == 0)
8211 err += efunc(pc, "cannot write to %r0\n");
8212 break;
8213 case DIF_OP_LDSB:
8214 case DIF_OP_LDSH:
8215 case DIF_OP_LDSW:
8216 case DIF_OP_LDUB:
8217 case DIF_OP_LDUH:
8218 case DIF_OP_LDUW:
8219 case DIF_OP_LDX:
8220 if (r1 >= nregs)
8221 err += efunc(pc, "invalid register %u\n", r1);
8222 if (r2 != 0)
8223 err += efunc(pc, "non-zero reserved bits\n");
8224 if (rd >= nregs)
8225 err += efunc(pc, "invalid register %u\n", rd);
8226 if (rd == 0)
8227 err += efunc(pc, "cannot write to %r0\n");
8228 if (kcheckload)
8229 dp->dtdo_buf[pc] = DIF_INSTR_LOAD(op +
8230 DIF_OP_RLDSB - DIF_OP_LDSB, r1, rd);
8231 break;
8232 case DIF_OP_RLDSB:
8233 case DIF_OP_RLDSH:
8234 case DIF_OP_RLDSW:
8235 case DIF_OP_RLDUB:
8236 case DIF_OP_RLDUH:
8237 case DIF_OP_RLDUW:
8238 case DIF_OP_RLDX:
8239 if (r1 >= nregs)
8240 err += efunc(pc, "invalid register %u\n", r1);
8241 if (r2 != 0)
8242 err += efunc(pc, "non-zero reserved bits\n");
8243 if (rd >= nregs)
8244 err += efunc(pc, "invalid register %u\n", rd);
8245 if (rd == 0)
8246 err += efunc(pc, "cannot write to %r0\n");
8247 break;
8248 case DIF_OP_ULDSB:
8249 case DIF_OP_ULDSH:
8250 case DIF_OP_ULDSW:
8251 case DIF_OP_ULDUB:
8252 case DIF_OP_ULDUH:
8253 case DIF_OP_ULDUW:
8254 case DIF_OP_ULDX:
8255 if (r1 >= nregs)
8256 err += efunc(pc, "invalid register %u\n", r1);
8257 if (r2 != 0)
8258 err += efunc(pc, "non-zero reserved bits\n");
8259 if (rd >= nregs)
8260 err += efunc(pc, "invalid register %u\n", rd);
8261 if (rd == 0)
8262 err += efunc(pc, "cannot write to %r0\n");
8263 break;
8264 case DIF_OP_STB:
8265 case DIF_OP_STH:
8266 case DIF_OP_STW:
8267 case DIF_OP_STX:
8268 if (r1 >= nregs)
8269 err += efunc(pc, "invalid register %u\n", r1);
8270 if (r2 != 0)
8271 err += efunc(pc, "non-zero reserved bits\n");
8272 if (rd >= nregs)
8273 err += efunc(pc, "invalid register %u\n", rd);
8274 if (rd == 0)
8275 err += efunc(pc, "cannot write to 0 address\n");
8276 break;
8277 case DIF_OP_CMP:
8278 case DIF_OP_SCMP:
8279 if (r1 >= nregs)
8280 err += efunc(pc, "invalid register %u\n", r1);
8281 if (r2 >= nregs)
8282 err += efunc(pc, "invalid register %u\n", r2);
8283 if (rd != 0)
8284 err += efunc(pc, "non-zero reserved bits\n");
8285 break;
8286 case DIF_OP_TST:
8287 if (r1 >= nregs)
8288 err += efunc(pc, "invalid register %u\n", r1);
8289 if (r2 != 0 || rd != 0)
8290 err += efunc(pc, "non-zero reserved bits\n");
8291 break;
8292 case DIF_OP_BA:
8293 case DIF_OP_BE:
8294 case DIF_OP_BNE:
8295 case DIF_OP_BG:
8296 case DIF_OP_BGU:
8297 case DIF_OP_BGE:
8298 case DIF_OP_BGEU:
8299 case DIF_OP_BL:
8300 case DIF_OP_BLU:
8301 case DIF_OP_BLE:
8302 case DIF_OP_BLEU:
8303 if (label >= dp->dtdo_len) {
8304 err += efunc(pc, "invalid branch target %u\n",
8305 label);
8306 }
8307 if (label <= pc) {
8308 err += efunc(pc, "backward branch to %u\n",
8309 label);
8310 }
8311 break;
8312 case DIF_OP_RET:
8313 if (r1 != 0 || r2 != 0)
8314 err += efunc(pc, "non-zero reserved bits\n");
8315 if (rd >= nregs)
8316 err += efunc(pc, "invalid register %u\n", rd);
8317 break;
8318 case DIF_OP_NOP:
8319 case DIF_OP_POPTS:
8320 case DIF_OP_FLUSHTS:
8321 if (r1 != 0 || r2 != 0 || rd != 0)
8322 err += efunc(pc, "non-zero reserved bits\n");
8323 break;
8324 case DIF_OP_SETX:
8325 if (DIF_INSTR_INTEGER(instr) >= dp->dtdo_intlen) {
8326 err += efunc(pc, "invalid integer ref %u\n",
8327 DIF_INSTR_INTEGER(instr));
8328 }
8329 if (rd >= nregs)
8330 err += efunc(pc, "invalid register %u\n", rd);
8331 if (rd == 0)
8332 err += efunc(pc, "cannot write to %r0\n");
8333 break;
8334 case DIF_OP_SETS:
8335 if (DIF_INSTR_STRING(instr) >= dp->dtdo_strlen) {
8336 err += efunc(pc, "invalid string ref %u\n",
8337 DIF_INSTR_STRING(instr));
8338 }
8339 if (rd >= nregs)
8340 err += efunc(pc, "invalid register %u\n", rd);
8341 if (rd == 0)
8342 err += efunc(pc, "cannot write to %r0\n");
8343 break;
8344 case DIF_OP_LDGA:
8345 case DIF_OP_LDTA:
8346 if (r1 > DIF_VAR_ARRAY_MAX)
8347 err += efunc(pc, "invalid array %u\n", r1);
8348 if (r2 >= nregs)
8349 err += efunc(pc, "invalid register %u\n", r2);
8350 if (rd >= nregs)
8351 err += efunc(pc, "invalid register %u\n", rd);
8352 if (rd == 0)
8353 err += efunc(pc, "cannot write to %r0\n");
8354 break;
8355 case DIF_OP_LDGS:
8356 case DIF_OP_LDTS:
8357 case DIF_OP_LDLS:
8358 case DIF_OP_LDGAA:
8359 case DIF_OP_LDTAA:
8360 if (v < DIF_VAR_OTHER_MIN || v > DIF_VAR_OTHER_MAX)
8361 err += efunc(pc, "invalid variable %u\n", v);
8362 if (rd >= nregs)
8363 err += efunc(pc, "invalid register %u\n", rd);
8364 if (rd == 0)
8365 err += efunc(pc, "cannot write to %r0\n");
8366 break;
8367 case DIF_OP_STGS:
8368 case DIF_OP_STTS:
8369 case DIF_OP_STLS:
8370 case DIF_OP_STGAA:
8371 case DIF_OP_STTAA:
8372 if (v < DIF_VAR_OTHER_UBASE || v > DIF_VAR_OTHER_MAX)
8373 err += efunc(pc, "invalid variable %u\n", v);
8374 if (rs >= nregs)
8375 err += efunc(pc, "invalid register %u\n", rd);
8376 break;
8377 case DIF_OP_CALL:
8378 if (subr > DIF_SUBR_MAX)
8379 err += efunc(pc, "invalid subr %u\n", subr);
8380 if (rd >= nregs)
8381 err += efunc(pc, "invalid register %u\n", rd);
8382 if (rd == 0)
8383 err += efunc(pc, "cannot write to %r0\n");
8384
8385 if (subr == DIF_SUBR_COPYOUT ||
8386 subr == DIF_SUBR_COPYOUTSTR) {
8387 dp->dtdo_destructive = 1;
8388 }
8389 break;
8390 case DIF_OP_PUSHTR:
8391 if (type != DIF_TYPE_STRING && type != DIF_TYPE_CTF)
8392 err += efunc(pc, "invalid ref type %u\n", type);
8393 if (r2 >= nregs)
8394 err += efunc(pc, "invalid register %u\n", r2);
8395 if (rs >= nregs)
8396 err += efunc(pc, "invalid register %u\n", rs);
8397 break;
8398 case DIF_OP_PUSHTV:
8399 if (type != DIF_TYPE_CTF)
8400 err += efunc(pc, "invalid val type %u\n", type);
8401 if (r2 >= nregs)
8402 err += efunc(pc, "invalid register %u\n", r2);
8403 if (rs >= nregs)
8404 err += efunc(pc, "invalid register %u\n", rs);
8405 break;
8406 default:
8407 err += efunc(pc, "invalid opcode %u\n",
8408 DIF_INSTR_OP(instr));
8409 }
8410 }
8411
8412 if (dp->dtdo_len != 0 &&
8413 DIF_INSTR_OP(dp->dtdo_buf[dp->dtdo_len - 1]) != DIF_OP_RET) {
8414 err += efunc(dp->dtdo_len - 1,
8415 "expected 'ret' as last DIF instruction\n");
8416 }
8417
8418 if (!(dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF)) {
8419 /*
8420 * If we're not returning by reference, the size must be either
8421 * 0 or the size of one of the base types.
8422 */
8423 switch (dp->dtdo_rtype.dtdt_size) {
8424 case 0:
8425 case sizeof (uint8_t):
8426 case sizeof (uint16_t):
8427 case sizeof (uint32_t):
8428 case sizeof (uint64_t):
8429 break;
8430
8431 default:
8432 err += efunc(dp->dtdo_len - 1, "bad return size\n");
8433 }
8434 }
8435
8436 for (i = 0; i < dp->dtdo_varlen && err == 0; i++) {
8437 dtrace_difv_t *v = &dp->dtdo_vartab[i], *existing = NULL;
8438 dtrace_diftype_t *vt, *et;
8439 uint_t id, ndx;
8440
8441 if (v->dtdv_scope != DIFV_SCOPE_GLOBAL &&
8442 v->dtdv_scope != DIFV_SCOPE_THREAD &&
8443 v->dtdv_scope != DIFV_SCOPE_LOCAL) {
8444 err += efunc(i, "unrecognized variable scope %d\n",
8445 v->dtdv_scope);
8446 break;
8447 }
8448
8449 if (v->dtdv_kind != DIFV_KIND_ARRAY &&
8450 v->dtdv_kind != DIFV_KIND_SCALAR) {
8451 err += efunc(i, "unrecognized variable type %d\n",
8452 v->dtdv_kind);
8453 break;
8454 }
8455
8456 if ((id = v->dtdv_id) > DIF_VARIABLE_MAX) {
8457 err += efunc(i, "%d exceeds variable id limit\n", id);
8458 break;
8459 }
8460
8461 if (id < DIF_VAR_OTHER_UBASE)
8462 continue;
8463
8464 /*
8465 * For user-defined variables, we need to check that this
8466 * definition is identical to any previous definition that we
8467 * encountered.
8468 */
8469 ndx = id - DIF_VAR_OTHER_UBASE;
8470
8471 switch (v->dtdv_scope) {
8472 case DIFV_SCOPE_GLOBAL:
8473 if (ndx < vstate->dtvs_nglobals) {
8474 dtrace_statvar_t *svar;
8475
8476 if ((svar = vstate->dtvs_globals[ndx]) != NULL)
8477 existing = &svar->dtsv_var;
8478 }
8479
8480 break;
8481
8482 case DIFV_SCOPE_THREAD:
8483 if (ndx < vstate->dtvs_ntlocals)
8484 existing = &vstate->dtvs_tlocals[ndx];
8485 break;
8486
8487 case DIFV_SCOPE_LOCAL:
8488 if (ndx < vstate->dtvs_nlocals) {
8489 dtrace_statvar_t *svar;
8490
8491 if ((svar = vstate->dtvs_locals[ndx]) != NULL)
8492 existing = &svar->dtsv_var;
8493 }
8494
8495 break;
8496 }
8497
8498 vt = &v->dtdv_type;
8499
8500 if (vt->dtdt_flags & DIF_TF_BYREF) {
8501 if (vt->dtdt_size == 0) {
8502 err += efunc(i, "zero-sized variable\n");
8503 break;
8504 }
8505
8506 if (v->dtdv_scope == DIFV_SCOPE_GLOBAL &&
8507 vt->dtdt_size > dtrace_global_maxsize) {
8508 err += efunc(i, "oversized by-ref global\n");
8509 break;
8510 }
8511 }
8512
8513 if (existing == NULL || existing->dtdv_id == 0)
8514 continue;
8515
8516 ASSERT(existing->dtdv_id == v->dtdv_id);
8517 ASSERT(existing->dtdv_scope == v->dtdv_scope);
8518
8519 if (existing->dtdv_kind != v->dtdv_kind)
8520 err += efunc(i, "%d changed variable kind\n", id);
8521
8522 et = &existing->dtdv_type;
8523
8524 if (vt->dtdt_flags != et->dtdt_flags) {
8525 err += efunc(i, "%d changed variable type flags\n", id);
8526 break;
8527 }
8528
8529 if (vt->dtdt_size != 0 && vt->dtdt_size != et->dtdt_size) {
8530 err += efunc(i, "%d changed variable type size\n", id);
8531 break;
8532 }
8533 }
8534
8535 return (err);
8536 }
8537
8538 /*
8539 * Validate a DTrace DIF object that it is to be used as a helper. Helpers
8540 * are much more constrained than normal DIFOs. Specifically, they may
8541 * not:
8542 *
8543 * 1. Make calls to subroutines other than copyin(), copyinstr() or
8544 * miscellaneous string routines
8545 * 2. Access DTrace variables other than the args[] array, and the
8546 * curthread, pid, ppid, tid, execname, zonename, uid and gid variables.
8547 * 3. Have thread-local variables.
8548 * 4. Have dynamic variables.
8549 */
8550 static int
8551 dtrace_difo_validate_helper(dtrace_difo_t *dp)
8552 {
8553 int (*efunc)(uint_t pc, const char *, ...) = dtrace_difo_err;
8554 int err = 0;
8555 uint_t pc;
8556
8557 for (pc = 0; pc < dp->dtdo_len; pc++) {
8558 dif_instr_t instr = dp->dtdo_buf[pc];
8559
8560 uint_t v = DIF_INSTR_VAR(instr);
8561 uint_t subr = DIF_INSTR_SUBR(instr);
8562 uint_t op = DIF_INSTR_OP(instr);
8563
8564 switch (op) {
8565 case DIF_OP_OR:
8566 case DIF_OP_XOR:
8567 case DIF_OP_AND:
8568 case DIF_OP_SLL:
8569 case DIF_OP_SRL:
8570 case DIF_OP_SRA:
8571 case DIF_OP_SUB:
8572 case DIF_OP_ADD:
8573 case DIF_OP_MUL:
8574 case DIF_OP_SDIV:
8575 case DIF_OP_UDIV:
8576 case DIF_OP_SREM:
8577 case DIF_OP_UREM:
8578 case DIF_OP_COPYS:
8579 case DIF_OP_NOT:
8580 case DIF_OP_MOV:
8581 case DIF_OP_RLDSB:
8582 case DIF_OP_RLDSH:
8583 case DIF_OP_RLDSW:
8584 case DIF_OP_RLDUB:
8585 case DIF_OP_RLDUH:
8586 case DIF_OP_RLDUW:
8587 case DIF_OP_RLDX:
8588 case DIF_OP_ULDSB:
8589 case DIF_OP_ULDSH:
8590 case DIF_OP_ULDSW:
8591 case DIF_OP_ULDUB:
8592 case DIF_OP_ULDUH:
8593 case DIF_OP_ULDUW:
8594 case DIF_OP_ULDX:
8595 case DIF_OP_STB:
8596 case DIF_OP_STH:
8597 case DIF_OP_STW:
8598 case DIF_OP_STX:
8599 case DIF_OP_ALLOCS:
8600 case DIF_OP_CMP:
8601 case DIF_OP_SCMP:
8602 case DIF_OP_TST:
8603 case DIF_OP_BA:
8604 case DIF_OP_BE:
8605 case DIF_OP_BNE:
8606 case DIF_OP_BG:
8607 case DIF_OP_BGU:
8608 case DIF_OP_BGE:
8609 case DIF_OP_BGEU:
8610 case DIF_OP_BL:
8611 case DIF_OP_BLU:
8612 case DIF_OP_BLE:
8613 case DIF_OP_BLEU:
8614 case DIF_OP_RET:
8615 case DIF_OP_NOP:
8616 case DIF_OP_POPTS:
8617 case DIF_OP_FLUSHTS:
8618 case DIF_OP_SETX:
8619 case DIF_OP_SETS:
8620 case DIF_OP_LDGA:
8621 case DIF_OP_LDLS:
8622 case DIF_OP_STGS:
8623 case DIF_OP_STLS:
8624 case DIF_OP_PUSHTR:
8625 case DIF_OP_PUSHTV:
8626 break;
8627
8628 case DIF_OP_LDGS:
8629 if (v >= DIF_VAR_OTHER_UBASE)
8630 break;
8631
8632 if (v >= DIF_VAR_ARG0 && v <= DIF_VAR_ARG9)
8633 break;
8634
8635 if (v == DIF_VAR_CURTHREAD || v == DIF_VAR_PID ||
8636 v == DIF_VAR_PPID || v == DIF_VAR_TID ||
8637 v == DIF_VAR_EXECNAME || v == DIF_VAR_ZONENAME ||
8638 v == DIF_VAR_UID || v == DIF_VAR_GID)
8639 break;
8640
8641 err += efunc(pc, "illegal variable %u\n", v);
8642 break;
8643
8644 case DIF_OP_LDTA:
8645 case DIF_OP_LDTS:
8646 case DIF_OP_LDGAA:
8647 case DIF_OP_LDTAA:
8648 err += efunc(pc, "illegal dynamic variable load\n");
8649 break;
8650
8651 case DIF_OP_STTS:
8652 case DIF_OP_STGAA:
8653 case DIF_OP_STTAA:
8654 err += efunc(pc, "illegal dynamic variable store\n");
8655 break;
8656
8657 case DIF_OP_CALL:
8658 if (subr == DIF_SUBR_ALLOCA ||
8659 subr == DIF_SUBR_BCOPY ||
8660 subr == DIF_SUBR_COPYIN ||
8661 subr == DIF_SUBR_COPYINTO ||
8662 subr == DIF_SUBR_COPYINSTR ||
8663 subr == DIF_SUBR_INDEX ||
8664 subr == DIF_SUBR_INET_NTOA ||
8665 subr == DIF_SUBR_INET_NTOA6 ||
8666 subr == DIF_SUBR_INET_NTOP ||
8667 subr == DIF_SUBR_LLTOSTR ||
8668 subr == DIF_SUBR_RINDEX ||
8669 subr == DIF_SUBR_STRCHR ||
8670 subr == DIF_SUBR_STRJOIN ||
8671 subr == DIF_SUBR_STRRCHR ||
8672 subr == DIF_SUBR_STRSTR ||
8673 subr == DIF_SUBR_HTONS ||
8674 subr == DIF_SUBR_HTONL ||
8675 subr == DIF_SUBR_HTONLL ||
8676 subr == DIF_SUBR_NTOHS ||
8677 subr == DIF_SUBR_NTOHL ||
8678 subr == DIF_SUBR_NTOHLL)
8679 break;
8680
8681 err += efunc(pc, "invalid subr %u\n", subr);
8682 break;
8683
8684 default:
8685 err += efunc(pc, "invalid opcode %u\n",
8686 DIF_INSTR_OP(instr));
8687 }
8688 }
8689
8690 return (err);
8691 }
8692
8693 /*
8694 * Returns 1 if the expression in the DIF object can be cached on a per-thread
8695 * basis; 0 if not.
8696 */
8697 static int
8698 dtrace_difo_cacheable(dtrace_difo_t *dp)
8699 {
8700 int i;
8701
8702 if (dp == NULL)
8703 return (0);
8704
8705 for (i = 0; i < dp->dtdo_varlen; i++) {
8706 dtrace_difv_t *v = &dp->dtdo_vartab[i];
8707
8708 if (v->dtdv_scope != DIFV_SCOPE_GLOBAL)
8709 continue;
8710
8711 switch (v->dtdv_id) {
8712 case DIF_VAR_CURTHREAD:
8713 case DIF_VAR_PID:
8714 case DIF_VAR_TID:
8715 case DIF_VAR_EXECNAME:
8716 case DIF_VAR_ZONENAME:
8717 break;
8718
8719 default:
8720 return (0);
8721 }
8722 }
8723
8724 /*
8725 * This DIF object may be cacheable. Now we need to look for any
8726 * array loading instructions, any memory loading instructions, or
8727 * any stores to thread-local variables.
8728 */
8729 for (i = 0; i < dp->dtdo_len; i++) {
8730 uint_t op = DIF_INSTR_OP(dp->dtdo_buf[i]);
8731
8732 if ((op >= DIF_OP_LDSB && op <= DIF_OP_LDX) ||
8733 (op >= DIF_OP_ULDSB && op <= DIF_OP_ULDX) ||
8734 (op >= DIF_OP_RLDSB && op <= DIF_OP_RLDX) ||
8735 op == DIF_OP_LDGA || op == DIF_OP_STTS)
8736 return (0);
8737 }
8738
8739 return (1);
8740 }
8741
8742 static void
8743 dtrace_difo_hold(dtrace_difo_t *dp)
8744 {
8745 int i;
8746
8747 ASSERT(MUTEX_HELD(&dtrace_lock));
8748
8749 dp->dtdo_refcnt++;
8750 ASSERT(dp->dtdo_refcnt != 0);
8751
8752 /*
8753 * We need to check this DIF object for references to the variable
8754 * DIF_VAR_VTIMESTAMP.
8755 */
8756 for (i = 0; i < dp->dtdo_varlen; i++) {
8757 dtrace_difv_t *v = &dp->dtdo_vartab[i];
8758
8759 if (v->dtdv_id != DIF_VAR_VTIMESTAMP)
8760 continue;
8761
8762 if (dtrace_vtime_references++ == 0)
8763 dtrace_vtime_enable();
8764 }
8765 }
8766
8767 /*
8768 * This routine calculates the dynamic variable chunksize for a given DIF
8769 * object. The calculation is not fool-proof, and can probably be tricked by
8770 * malicious DIF -- but it works for all compiler-generated DIF. Because this
8771 * calculation is likely imperfect, dtrace_dynvar() is able to gracefully fail
8772 * if a dynamic variable size exceeds the chunksize.
8773 */
8774 static void
8775 dtrace_difo_chunksize(dtrace_difo_t *dp, dtrace_vstate_t *vstate)
8776 {
8777 uint64_t sval;
8778 dtrace_key_t tupregs[DIF_DTR_NREGS + 2]; /* +2 for thread and id */
8779 const dif_instr_t *text = dp->dtdo_buf;
8780 uint_t pc, srd = 0;
8781 uint_t ttop = 0;
8782 size_t size, ksize;
8783 uint_t id, i;
8784
8785 for (pc = 0; pc < dp->dtdo_len; pc++) {
8786 dif_instr_t instr = text[pc];
8787 uint_t op = DIF_INSTR_OP(instr);
8788 uint_t rd = DIF_INSTR_RD(instr);
8789 uint_t r1 = DIF_INSTR_R1(instr);
8790 uint_t nkeys = 0;
8791 uchar_t scope;
8792
8793 dtrace_key_t *key = tupregs;
8794
8795 switch (op) {
8796 case DIF_OP_SETX:
8797 sval = dp->dtdo_inttab[DIF_INSTR_INTEGER(instr)];
8798 srd = rd;
8799 continue;
8800
8801 case DIF_OP_STTS:
8802 key = &tupregs[DIF_DTR_NREGS];
8803 key[0].dttk_size = 0;
8804 key[1].dttk_size = 0;
8805 nkeys = 2;
8806 scope = DIFV_SCOPE_THREAD;
8807 break;
8808
8809 case DIF_OP_STGAA:
8810 case DIF_OP_STTAA:
8811 nkeys = ttop;
8812
8813 if (DIF_INSTR_OP(instr) == DIF_OP_STTAA)
8814 key[nkeys++].dttk_size = 0;
8815
8816 key[nkeys++].dttk_size = 0;
8817
8818 if (op == DIF_OP_STTAA) {
8819 scope = DIFV_SCOPE_THREAD;
8820 } else {
8821 scope = DIFV_SCOPE_GLOBAL;
8822 }
8823
8824 break;
8825
8826 case DIF_OP_PUSHTR:
8827 if (ttop == DIF_DTR_NREGS)
8828 return;
8829
8830 if ((srd == 0 || sval == 0) && r1 == DIF_TYPE_STRING) {
8831 /*
8832 * If the register for the size of the "pushtr"
8833 * is %r0 (or the value is 0) and the type is
8834 * a string, we'll use the system-wide default
8835 * string size.
8836 */
8837 tupregs[ttop++].dttk_size =
8838 dtrace_strsize_default;
8839 } else {
8840 if (srd == 0)
8841 return;
8842
8843 tupregs[ttop++].dttk_size = sval;
8844 }
8845
8846 break;
8847
8848 case DIF_OP_PUSHTV:
8849 if (ttop == DIF_DTR_NREGS)
8850 return;
8851
8852 tupregs[ttop++].dttk_size = 0;
8853 break;
8854
8855 case DIF_OP_FLUSHTS:
8856 ttop = 0;
8857 break;
8858
8859 case DIF_OP_POPTS:
8860 if (ttop != 0)
8861 ttop--;
8862 break;
8863 }
8864
8865 sval = 0;
8866 srd = 0;
8867
8868 if (nkeys == 0)
8869 continue;
8870
8871 /*
8872 * We have a dynamic variable allocation; calculate its size.
8873 */
8874 for (ksize = 0, i = 0; i < nkeys; i++)
8875 ksize += P2ROUNDUP(key[i].dttk_size, sizeof (uint64_t));
8876
8877 size = sizeof (dtrace_dynvar_t);
8878 size += sizeof (dtrace_key_t) * (nkeys - 1);
8879 size += ksize;
8880
8881 /*
8882 * Now we need to determine the size of the stored data.
8883 */
8884 id = DIF_INSTR_VAR(instr);
8885
8886 for (i = 0; i < dp->dtdo_varlen; i++) {
8887 dtrace_difv_t *v = &dp->dtdo_vartab[i];
8888
8889 if (v->dtdv_id == id && v->dtdv_scope == scope) {
8890 size += v->dtdv_type.dtdt_size;
8891 break;
8892 }
8893 }
8894
8895 if (i == dp->dtdo_varlen)
8896 return;
8897
8898 /*
8899 * We have the size. If this is larger than the chunk size
8900 * for our dynamic variable state, reset the chunk size.
8901 */
8902 size = P2ROUNDUP(size, sizeof (uint64_t));
8903
8904 if (size > vstate->dtvs_dynvars.dtds_chunksize)
8905 vstate->dtvs_dynvars.dtds_chunksize = size;
8906 }
8907 }
8908
8909 static void
8910 dtrace_difo_init(dtrace_difo_t *dp, dtrace_vstate_t *vstate)
8911 {
8912 int i, oldsvars, osz, nsz, otlocals, ntlocals;
8913 uint_t id;
8914
8915 ASSERT(MUTEX_HELD(&dtrace_lock));
8916 ASSERT(dp->dtdo_buf != NULL && dp->dtdo_len != 0);
8917
8918 for (i = 0; i < dp->dtdo_varlen; i++) {
8919 dtrace_difv_t *v = &dp->dtdo_vartab[i];
8920 dtrace_statvar_t *svar, ***svarp;
8921 size_t dsize = 0;
8922 uint8_t scope = v->dtdv_scope;
8923 int *np;
8924
8925 if ((id = v->dtdv_id) < DIF_VAR_OTHER_UBASE)
8926 continue;
8927
8928 id -= DIF_VAR_OTHER_UBASE;
8929
8930 switch (scope) {
8931 case DIFV_SCOPE_THREAD:
8932 while (id >= (otlocals = vstate->dtvs_ntlocals)) {
8933 dtrace_difv_t *tlocals;
8934
8935 if ((ntlocals = (otlocals << 1)) == 0)
8936 ntlocals = 1;
8937
8938 osz = otlocals * sizeof (dtrace_difv_t);
8939 nsz = ntlocals * sizeof (dtrace_difv_t);
8940
8941 tlocals = kmem_zalloc(nsz, KM_SLEEP);
8942
8943 if (osz != 0) {
8944 bcopy(vstate->dtvs_tlocals,
8945 tlocals, osz);
8946 kmem_free(vstate->dtvs_tlocals, osz);
8947 }
8948
8949 vstate->dtvs_tlocals = tlocals;
8950 vstate->dtvs_ntlocals = ntlocals;
8951 }
8952
8953 vstate->dtvs_tlocals[id] = *v;
8954 continue;
8955
8956 case DIFV_SCOPE_LOCAL:
8957 np = &vstate->dtvs_nlocals;
8958 svarp = &vstate->dtvs_locals;
8959
8960 if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF)
8961 dsize = NCPU * (v->dtdv_type.dtdt_size +
8962 sizeof (uint64_t));
8963 else
8964 dsize = NCPU * sizeof (uint64_t);
8965
8966 break;
8967
8968 case DIFV_SCOPE_GLOBAL:
8969 np = &vstate->dtvs_nglobals;
8970 svarp = &vstate->dtvs_globals;
8971
8972 if (v->dtdv_type.dtdt_flags & DIF_TF_BYREF)
8973 dsize = v->dtdv_type.dtdt_size +
8974 sizeof (uint64_t);
8975
8976 break;
8977
8978 default:
8979 ASSERT(0);
8980 }
8981
8982 while (id >= (oldsvars = *np)) {
8983 dtrace_statvar_t **statics;
8984 int newsvars, oldsize, newsize;
8985
8986 if ((newsvars = (oldsvars << 1)) == 0)
8987 newsvars = 1;
8988
8989 oldsize = oldsvars * sizeof (dtrace_statvar_t *);
8990 newsize = newsvars * sizeof (dtrace_statvar_t *);
8991
8992 statics = kmem_zalloc(newsize, KM_SLEEP);
8993
8994 if (oldsize != 0) {
8995 bcopy(*svarp, statics, oldsize);
8996 kmem_free(*svarp, oldsize);
8997 }
8998
8999 *svarp = statics;
9000 *np = newsvars;
9001 }
9002
9003 if ((svar = (*svarp)[id]) == NULL) {
9004 svar = kmem_zalloc(sizeof (dtrace_statvar_t), KM_SLEEP);
9005 svar->dtsv_var = *v;
9006
9007 if ((svar->dtsv_size = dsize) != 0) {
9008 svar->dtsv_data = (uint64_t)(uintptr_t)
9009 kmem_zalloc(dsize, KM_SLEEP);
9010 }
9011
9012 (*svarp)[id] = svar;
9013 }
9014
9015 svar->dtsv_refcnt++;
9016 }
9017
9018 dtrace_difo_chunksize(dp, vstate);
9019 dtrace_difo_hold(dp);
9020 }
9021
9022 static dtrace_difo_t *
9023 dtrace_difo_duplicate(dtrace_difo_t *dp, dtrace_vstate_t *vstate)
9024 {
9025 dtrace_difo_t *new;
9026 size_t sz;
9027
9028 ASSERT(dp->dtdo_buf != NULL);
9029 ASSERT(dp->dtdo_refcnt != 0);
9030
9031 new = kmem_zalloc(sizeof (dtrace_difo_t), KM_SLEEP);
9032
9033 ASSERT(dp->dtdo_buf != NULL);
9034 sz = dp->dtdo_len * sizeof (dif_instr_t);
9035 new->dtdo_buf = kmem_alloc(sz, KM_SLEEP);
9036 bcopy(dp->dtdo_buf, new->dtdo_buf, sz);
9037 new->dtdo_len = dp->dtdo_len;
9038
9039 if (dp->dtdo_strtab != NULL) {
9040 ASSERT(dp->dtdo_strlen != 0);
9041 new->dtdo_strtab = kmem_alloc(dp->dtdo_strlen, KM_SLEEP);
9042 bcopy(dp->dtdo_strtab, new->dtdo_strtab, dp->dtdo_strlen);
9043 new->dtdo_strlen = dp->dtdo_strlen;
9044 }
9045
9046 if (dp->dtdo_inttab != NULL) {
9047 ASSERT(dp->dtdo_intlen != 0);
9048 sz = dp->dtdo_intlen * sizeof (uint64_t);
9049 new->dtdo_inttab = kmem_alloc(sz, KM_SLEEP);
9050 bcopy(dp->dtdo_inttab, new->dtdo_inttab, sz);
9051 new->dtdo_intlen = dp->dtdo_intlen;
9052 }
9053
9054 if (dp->dtdo_vartab != NULL) {
9055 ASSERT(dp->dtdo_varlen != 0);
9056 sz = dp->dtdo_varlen * sizeof (dtrace_difv_t);
9057 new->dtdo_vartab = kmem_alloc(sz, KM_SLEEP);
9058 bcopy(dp->dtdo_vartab, new->dtdo_vartab, sz);
9059 new->dtdo_varlen = dp->dtdo_varlen;
9060 }
9061
9062 dtrace_difo_init(new, vstate);
9063 return (new);
9064 }
9065
9066 static void
9067 dtrace_difo_destroy(dtrace_difo_t *dp, dtrace_vstate_t *vstate)
9068 {
9069 int i;
9070
9071 ASSERT(dp->dtdo_refcnt == 0);
9072
9073 for (i = 0; i < dp->dtdo_varlen; i++) {
9074 dtrace_difv_t *v = &dp->dtdo_vartab[i];
9075 dtrace_statvar_t *svar, **svarp;
9076 uint_t id;
9077 uint8_t scope = v->dtdv_scope;
9078 int *np;
9079
9080 switch (scope) {
9081 case DIFV_SCOPE_THREAD:
9082 continue;
9083
9084 case DIFV_SCOPE_LOCAL:
9085 np = &vstate->dtvs_nlocals;
9086 svarp = vstate->dtvs_locals;
9087 break;
9088
9089 case DIFV_SCOPE_GLOBAL:
9090 np = &vstate->dtvs_nglobals;
9091 svarp = vstate->dtvs_globals;
9092 break;
9093
9094 default:
9095 ASSERT(0);
9096 }
9097
9098 if ((id = v->dtdv_id) < DIF_VAR_OTHER_UBASE)
9099 continue;
9100
9101 id -= DIF_VAR_OTHER_UBASE;
9102 ASSERT(id < *np);
9103
9104 svar = svarp[id];
9105 ASSERT(svar != NULL);
9106 ASSERT(svar->dtsv_refcnt > 0);
9107
9108 if (--svar->dtsv_refcnt > 0)
9109 continue;
9110
9111 if (svar->dtsv_size != 0) {
9112 ASSERT(svar->dtsv_data != NULL);
9113 kmem_free((void *)(uintptr_t)svar->dtsv_data,
9114 svar->dtsv_size);
9115 }
9116
9117 kmem_free(svar, sizeof (dtrace_statvar_t));
9118 svarp[id] = NULL;
9119 }
9120
9121 kmem_free(dp->dtdo_buf, dp->dtdo_len * sizeof (dif_instr_t));
9122 kmem_free(dp->dtdo_inttab, dp->dtdo_intlen * sizeof (uint64_t));
9123 kmem_free(dp->dtdo_strtab, dp->dtdo_strlen);
9124 kmem_free(dp->dtdo_vartab, dp->dtdo_varlen * sizeof (dtrace_difv_t));
9125
9126 kmem_free(dp, sizeof (dtrace_difo_t));
9127 }
9128
9129 static void
9130 dtrace_difo_release(dtrace_difo_t *dp, dtrace_vstate_t *vstate)
9131 {
9132 int i;
9133
9134 ASSERT(MUTEX_HELD(&dtrace_lock));
9135 ASSERT(dp->dtdo_refcnt != 0);
9136
9137 for (i = 0; i < dp->dtdo_varlen; i++) {
9138 dtrace_difv_t *v = &dp->dtdo_vartab[i];
9139
9140 if (v->dtdv_id != DIF_VAR_VTIMESTAMP)
9141 continue;
9142
9143 ASSERT(dtrace_vtime_references > 0);
9144 if (--dtrace_vtime_references == 0)
9145 dtrace_vtime_disable();
9146 }
9147
9148 if (--dp->dtdo_refcnt == 0)
9149 dtrace_difo_destroy(dp, vstate);
9150 }
9151
9152 /*
9153 * DTrace Format Functions
9154 */
9155 static uint16_t
9156 dtrace_format_add(dtrace_state_t *state, char *str)
9157 {
9158 char *fmt, **new;
9159 uint16_t ndx, len = strlen(str) + 1;
9160
9161 fmt = kmem_zalloc(len, KM_SLEEP);
9162 bcopy(str, fmt, len);
9163
9164 for (ndx = 0; ndx < state->dts_nformats; ndx++) {
9165 if (state->dts_formats[ndx] == NULL) {
9166 state->dts_formats[ndx] = fmt;
9167 return (ndx + 1);
9168 }
9169 }
9170
9171 if (state->dts_nformats == USHRT_MAX) {
9172 /*
9173 * This is only likely if a denial-of-service attack is being
9174 * attempted. As such, it's okay to fail silently here.
9175 */
9176 kmem_free(fmt, len);
9177 return (0);
9178 }
9179
9180 /*
9181 * For simplicity, we always resize the formats array to be exactly the
9182 * number of formats.
9183 */
9184 ndx = state->dts_nformats++;
9185 new = kmem_alloc((ndx + 1) * sizeof (char *), KM_SLEEP);
9186
9187 if (state->dts_formats != NULL) {
9188 ASSERT(ndx != 0);
9189 bcopy(state->dts_formats, new, ndx * sizeof (char *));
9190 kmem_free(state->dts_formats, ndx * sizeof (char *));
9191 }
9192
9193 state->dts_formats = new;
9194 state->dts_formats[ndx] = fmt;
9195
9196 return (ndx + 1);
9197 }
9198
9199 static void
9200 dtrace_format_remove(dtrace_state_t *state, uint16_t format)
9201 {
9202 char *fmt;
9203
9204 ASSERT(state->dts_formats != NULL);
9205 ASSERT(format <= state->dts_nformats);
9206 ASSERT(state->dts_formats[format - 1] != NULL);
9207
9208 fmt = state->dts_formats[format - 1];
9209 kmem_free(fmt, strlen(fmt) + 1);
9210 state->dts_formats[format - 1] = NULL;
9211 }
9212
9213 static void
9214 dtrace_format_destroy(dtrace_state_t *state)
9215 {
9216 int i;
9217
9218 if (state->dts_nformats == 0) {
9219 ASSERT(state->dts_formats == NULL);
9220 return;
9221 }
9222
9223 ASSERT(state->dts_formats != NULL);
9224
9225 for (i = 0; i < state->dts_nformats; i++) {
9226 char *fmt = state->dts_formats[i];
9227
9228 if (fmt == NULL)
9229 continue;
9230
9231 kmem_free(fmt, strlen(fmt) + 1);
9232 }
9233
9234 kmem_free(state->dts_formats, state->dts_nformats * sizeof (char *));
9235 state->dts_nformats = 0;
9236 state->dts_formats = NULL;
9237 }
9238
9239 /*
9240 * DTrace Predicate Functions
9241 */
9242 static dtrace_predicate_t *
9243 dtrace_predicate_create(dtrace_difo_t *dp)
9244 {
9245 dtrace_predicate_t *pred;
9246
9247 ASSERT(MUTEX_HELD(&dtrace_lock));
9248 ASSERT(dp->dtdo_refcnt != 0);
9249
9250 pred = kmem_zalloc(sizeof (dtrace_predicate_t), KM_SLEEP);
9251 pred->dtp_difo = dp;
9252 pred->dtp_refcnt = 1;
9253
9254 if (!dtrace_difo_cacheable(dp))
9255 return (pred);
9256
9257 if (dtrace_predcache_id == DTRACE_CACHEIDNONE) {
9258 /*
9259 * This is only theoretically possible -- we have had 2^32
9260 * cacheable predicates on this machine. We cannot allow any
9261 * more predicates to become cacheable: as unlikely as it is,
9262 * there may be a thread caching a (now stale) predicate cache
9263 * ID. (N.B.: the temptation is being successfully resisted to
9264 * have this cmn_err() "Holy shit -- we executed this code!")
9265 */
9266 return (pred);
9267 }
9268
9269 pred->dtp_cacheid = dtrace_predcache_id++;
9270
9271 return (pred);
9272 }
9273
9274 static void
9275 dtrace_predicate_hold(dtrace_predicate_t *pred)
9276 {
9277 ASSERT(MUTEX_HELD(&dtrace_lock));
9278 ASSERT(pred->dtp_difo != NULL && pred->dtp_difo->dtdo_refcnt != 0);
9279 ASSERT(pred->dtp_refcnt > 0);
9280
9281 pred->dtp_refcnt++;
9282 }
9283
9284 static void
9285 dtrace_predicate_release(dtrace_predicate_t *pred, dtrace_vstate_t *vstate)
9286 {
9287 dtrace_difo_t *dp = pred->dtp_difo;
9288
9289 ASSERT(MUTEX_HELD(&dtrace_lock));
9290 ASSERT(dp != NULL && dp->dtdo_refcnt != 0);
9291 ASSERT(pred->dtp_refcnt > 0);
9292
9293 if (--pred->dtp_refcnt == 0) {
9294 dtrace_difo_release(pred->dtp_difo, vstate);
9295 kmem_free(pred, sizeof (dtrace_predicate_t));
9296 }
9297 }
9298
9299 /*
9300 * DTrace Action Description Functions
9301 */
9302 static dtrace_actdesc_t *
9303 dtrace_actdesc_create(dtrace_actkind_t kind, uint32_t ntuple,
9304 uint64_t uarg, uint64_t arg)
9305 {
9306 dtrace_actdesc_t *act;
9307
9308 ASSERT(!DTRACEACT_ISPRINTFLIKE(kind) || (arg != NULL &&
9309 arg >= KERNELBASE) || (arg == NULL && kind == DTRACEACT_PRINTA));
9310
9311 act = kmem_zalloc(sizeof (dtrace_actdesc_t), KM_SLEEP);
9312 act->dtad_kind = kind;
9313 act->dtad_ntuple = ntuple;
9314 act->dtad_uarg = uarg;
9315 act->dtad_arg = arg;
9316 act->dtad_refcnt = 1;
9317
9318 return (act);
9319 }
9320
9321 static void
9322 dtrace_actdesc_hold(dtrace_actdesc_t *act)
9323 {
9324 ASSERT(act->dtad_refcnt >= 1);
9325 act->dtad_refcnt++;
9326 }
9327
9328 static void
9329 dtrace_actdesc_release(dtrace_actdesc_t *act, dtrace_vstate_t *vstate)
9330 {
9331 dtrace_actkind_t kind = act->dtad_kind;
9332 dtrace_difo_t *dp;
9333
9334 ASSERT(act->dtad_refcnt >= 1);
9335
9336 if (--act->dtad_refcnt != 0)
9337 return;
9338
9339 if ((dp = act->dtad_difo) != NULL)
9340 dtrace_difo_release(dp, vstate);
9341
9342 if (DTRACEACT_ISPRINTFLIKE(kind)) {
9343 char *str = (char *)(uintptr_t)act->dtad_arg;
9344
9345 ASSERT((str != NULL && (uintptr_t)str >= KERNELBASE) ||
9346 (str == NULL && act->dtad_kind == DTRACEACT_PRINTA));
9347
9348 if (str != NULL)
9349 kmem_free(str, strlen(str) + 1);
9350 }
9351
9352 kmem_free(act, sizeof (dtrace_actdesc_t));
9353 }
9354
9355 /*
9356 * DTrace ECB Functions
9357 */
9358 static dtrace_ecb_t *
9359 dtrace_ecb_add(dtrace_state_t *state, dtrace_probe_t *probe)
9360 {
9361 dtrace_ecb_t *ecb;
9362 dtrace_epid_t epid;
9363
9364 ASSERT(MUTEX_HELD(&dtrace_lock));
9365
9366 ecb = kmem_zalloc(sizeof (dtrace_ecb_t), KM_SLEEP);
9367 ecb->dte_predicate = NULL;
9368 ecb->dte_probe = probe;
9369
9370 /*
9371 * The default size is the size of the default action: recording
9372 * the epid.
9373 */
9374 ecb->dte_size = ecb->dte_needed = sizeof (dtrace_epid_t);
9375 ecb->dte_alignment = sizeof (dtrace_epid_t);
9376
9377 epid = state->dts_epid++;
9378
9379 if (epid - 1 >= state->dts_necbs) {
9380 dtrace_ecb_t **oecbs = state->dts_ecbs, **ecbs;
9381 int necbs = state->dts_necbs << 1;
9382
9383 ASSERT(epid == state->dts_necbs + 1);
9384
9385 if (necbs == 0) {
9386 ASSERT(oecbs == NULL);
9387 necbs = 1;
9388 }
9389
9390 ecbs = kmem_zalloc(necbs * sizeof (*ecbs), KM_SLEEP);
9391
9392 if (oecbs != NULL)
9393 bcopy(oecbs, ecbs, state->dts_necbs * sizeof (*ecbs));
9394
9395 dtrace_membar_producer();
9396 state->dts_ecbs = ecbs;
9397
9398 if (oecbs != NULL) {
9399 /*
9400 * If this state is active, we must dtrace_sync()
9401 * before we can free the old dts_ecbs array: we're
9402 * coming in hot, and there may be active ring
9403 * buffer processing (which indexes into the dts_ecbs
9404 * array) on another CPU.
9405 */
9406 if (state->dts_activity != DTRACE_ACTIVITY_INACTIVE)
9407 dtrace_sync();
9408
9409 kmem_free(oecbs, state->dts_necbs * sizeof (*ecbs));
9410 }
9411
9412 dtrace_membar_producer();
9413 state->dts_necbs = necbs;
9414 }
9415
9416 ecb->dte_state = state;
9417
9418 ASSERT(state->dts_ecbs[epid - 1] == NULL);
9419 dtrace_membar_producer();
9420 state->dts_ecbs[(ecb->dte_epid = epid) - 1] = ecb;
9421
9422 return (ecb);
9423 }
9424
9425 static int
9426 dtrace_ecb_enable(dtrace_ecb_t *ecb)
9427 {
9428 dtrace_probe_t *probe = ecb->dte_probe;
9429
9430 ASSERT(MUTEX_HELD(&cpu_lock));
9431 ASSERT(MUTEX_HELD(&dtrace_lock));
9432 ASSERT(ecb->dte_next == NULL);
9433
9434 if (probe == NULL) {
9435 /*
9436 * This is the NULL probe -- there's nothing to do.
9437 */
9438 return (0);
9439 }
9440
9441 if (probe->dtpr_ecb == NULL) {
9442 dtrace_provider_t *prov = probe->dtpr_provider;
9443
9444 /*
9445 * We're the first ECB on this probe.
9446 */
9447 probe->dtpr_ecb = probe->dtpr_ecb_last = ecb;
9448
9449 if (ecb->dte_predicate != NULL)
9450 probe->dtpr_predcache = ecb->dte_predicate->dtp_cacheid;
9451
9452 return (prov->dtpv_pops.dtps_enable(prov->dtpv_arg,
9453 probe->dtpr_id, probe->dtpr_arg));
9454 } else {
9455 /*
9456 * This probe is already active. Swing the last pointer to
9457 * point to the new ECB, and issue a dtrace_sync() to assure
9458 * that all CPUs have seen the change.
9459 */
9460 ASSERT(probe->dtpr_ecb_last != NULL);
9461 probe->dtpr_ecb_last->dte_next = ecb;
9462 probe->dtpr_ecb_last = ecb;
9463 probe->dtpr_predcache = 0;
9464
9465 dtrace_sync();
9466 return (0);
9467 }
9468 }
9469
9470 static void
9471 dtrace_ecb_resize(dtrace_ecb_t *ecb)
9472 {
9473 uint32_t maxalign = sizeof (dtrace_epid_t);
9474 uint32_t align = sizeof (uint8_t), offs, diff;
9475 dtrace_action_t *act;
9476 int wastuple = 0;
9477 uint32_t aggbase = UINT32_MAX;
9478 dtrace_state_t *state = ecb->dte_state;
9479
9480 /*
9481 * If we record anything, we always record the epid. (And we always
9482 * record it first.)
9483 */
9484 offs = sizeof (dtrace_epid_t);
9485 ecb->dte_size = ecb->dte_needed = sizeof (dtrace_epid_t);
9486
9487 for (act = ecb->dte_action; act != NULL; act = act->dta_next) {
9488 dtrace_recdesc_t *rec = &act->dta_rec;
9489
9490 if ((align = rec->dtrd_alignment) > maxalign)
9491 maxalign = align;
9492
9493 if (!wastuple && act->dta_intuple) {
9494 /*
9495 * This is the first record in a tuple. Align the
9496 * offset to be at offset 4 in an 8-byte aligned
9497 * block.
9498 */
9499 diff = offs + sizeof (dtrace_aggid_t);
9500
9501 if (diff = (diff & (sizeof (uint64_t) - 1)))
9502 offs += sizeof (uint64_t) - diff;
9503
9504 aggbase = offs - sizeof (dtrace_aggid_t);
9505 ASSERT(!(aggbase & (sizeof (uint64_t) - 1)));
9506 }
9507
9508 /*LINTED*/
9509 if (rec->dtrd_size != 0 && (diff = (offs & (align - 1)))) {
9510 /*
9511 * The current offset is not properly aligned; align it.
9512 */
9513 offs += align - diff;
9514 }
9515
9516 rec->dtrd_offset = offs;
9517
9518 if (offs + rec->dtrd_size > ecb->dte_needed) {
9519 ecb->dte_needed = offs + rec->dtrd_size;
9520
9521 if (ecb->dte_needed > state->dts_needed)
9522 state->dts_needed = ecb->dte_needed;
9523 }
9524
9525 if (DTRACEACT_ISAGG(act->dta_kind)) {
9526 dtrace_aggregation_t *agg = (dtrace_aggregation_t *)act;
9527 dtrace_action_t *first = agg->dtag_first, *prev;
9528
9529 ASSERT(rec->dtrd_size != 0 && first != NULL);
9530 ASSERT(wastuple);
9531 ASSERT(aggbase != UINT32_MAX);
9532
9533 agg->dtag_base = aggbase;
9534
9535 while ((prev = first->dta_prev) != NULL &&
9536 DTRACEACT_ISAGG(prev->dta_kind)) {
9537 agg = (dtrace_aggregation_t *)prev;
9538 first = agg->dtag_first;
9539 }
9540
9541 if (prev != NULL) {
9542 offs = prev->dta_rec.dtrd_offset +
9543 prev->dta_rec.dtrd_size;
9544 } else {
9545 offs = sizeof (dtrace_epid_t);
9546 }
9547 wastuple = 0;
9548 } else {
9549 if (!act->dta_intuple)
9550 ecb->dte_size = offs + rec->dtrd_size;
9551
9552 offs += rec->dtrd_size;
9553 }
9554
9555 wastuple = act->dta_intuple;
9556 }
9557
9558 if ((act = ecb->dte_action) != NULL &&
9559 !(act->dta_kind == DTRACEACT_SPECULATE && act->dta_next == NULL) &&
9560 ecb->dte_size == sizeof (dtrace_epid_t)) {
9561 /*
9562 * If the size is still sizeof (dtrace_epid_t), then all
9563 * actions store no data; set the size to 0.
9564 */
9565 ecb->dte_alignment = maxalign;
9566 ecb->dte_size = 0;
9567
9568 /*
9569 * If the needed space is still sizeof (dtrace_epid_t), then
9570 * all actions need no additional space; set the needed
9571 * size to 0.
9572 */
9573 if (ecb->dte_needed == sizeof (dtrace_epid_t))
9574 ecb->dte_needed = 0;
9575
9576 return;
9577 }
9578
9579 /*
9580 * Set our alignment, and make sure that the dte_size and dte_needed
9581 * are aligned to the size of an EPID.
9582 */
9583 ecb->dte_alignment = maxalign;
9584 ecb->dte_size = (ecb->dte_size + (sizeof (dtrace_epid_t) - 1)) &
9585 ~(sizeof (dtrace_epid_t) - 1);
9586 ecb->dte_needed = (ecb->dte_needed + (sizeof (dtrace_epid_t) - 1)) &
9587 ~(sizeof (dtrace_epid_t) - 1);
9588 ASSERT(ecb->dte_size <= ecb->dte_needed);
9589 }
9590
9591 static dtrace_action_t *
9592 dtrace_ecb_aggregation_create(dtrace_ecb_t *ecb, dtrace_actdesc_t *desc)
9593 {
9594 dtrace_aggregation_t *agg;
9595 size_t size = sizeof (uint64_t);
9596 int ntuple = desc->dtad_ntuple;
9597 dtrace_action_t *act;
9598 dtrace_recdesc_t *frec;
9599 dtrace_aggid_t aggid;
9600 dtrace_state_t *state = ecb->dte_state;
9601
9602 agg = kmem_zalloc(sizeof (dtrace_aggregation_t), KM_SLEEP);
9603 agg->dtag_ecb = ecb;
9604
9605 ASSERT(DTRACEACT_ISAGG(desc->dtad_kind));
9606
9607 switch (desc->dtad_kind) {
9608 case DTRACEAGG_MIN:
9609 agg->dtag_initial = INT64_MAX;
9610 agg->dtag_aggregate = dtrace_aggregate_min;
9611 break;
9612
9613 case DTRACEAGG_MAX:
9614 agg->dtag_initial = INT64_MIN;
9615 agg->dtag_aggregate = dtrace_aggregate_max;
9616 break;
9617
9618 case DTRACEAGG_COUNT:
9619 agg->dtag_aggregate = dtrace_aggregate_count;
9620 break;
9621
9622 case DTRACEAGG_QUANTIZE:
9623 agg->dtag_aggregate = dtrace_aggregate_quantize;
9624 size = (((sizeof (uint64_t) * NBBY) - 1) * 2 + 1) *
9625 sizeof (uint64_t);
9626 break;
9627
9628 case DTRACEAGG_LQUANTIZE: {
9629 uint16_t step = DTRACE_LQUANTIZE_STEP(desc->dtad_arg);
9630 uint16_t levels = DTRACE_LQUANTIZE_LEVELS(desc->dtad_arg);
9631
9632 agg->dtag_initial = desc->dtad_arg;
9633 agg->dtag_aggregate = dtrace_aggregate_lquantize;
9634
9635 if (step == 0 || levels == 0)
9636 goto err;
9637
9638 size = levels * sizeof (uint64_t) + 3 * sizeof (uint64_t);
9639 break;
9640 }
9641
9642 case DTRACEAGG_LLQUANTIZE: {
9643 uint16_t factor = DTRACE_LLQUANTIZE_FACTOR(desc->dtad_arg);
9644 uint16_t low = DTRACE_LLQUANTIZE_LOW(desc->dtad_arg);
9645 uint16_t high = DTRACE_LLQUANTIZE_HIGH(desc->dtad_arg);
9646 uint16_t nsteps = DTRACE_LLQUANTIZE_NSTEP(desc->dtad_arg);
9647 int64_t v;
9648
9649 agg->dtag_initial = desc->dtad_arg;
9650 agg->dtag_aggregate = dtrace_aggregate_llquantize;
9651
9652 if (factor < 2 || low >= high || nsteps < factor)
9653 goto err;
9654
9655 /*
9656 * Now check that the number of steps evenly divides a power
9657 * of the factor. (This assures both integer bucket size and
9658 * linearity within each magnitude.)
9659 */
9660 for (v = factor; v < nsteps; v *= factor)
9661 continue;
9662
9663 if ((v % nsteps) || (nsteps % factor))
9664 goto err;
9665
9666 size = (dtrace_aggregate_llquantize_bucket(factor,
9667 low, high, nsteps, INT64_MAX) + 2) * sizeof (uint64_t);
9668 break;
9669 }
9670
9671 case DTRACEAGG_AVG:
9672 agg->dtag_aggregate = dtrace_aggregate_avg;
9673 size = sizeof (uint64_t) * 2;
9674 break;
9675
9676 case DTRACEAGG_STDDEV:
9677 agg->dtag_aggregate = dtrace_aggregate_stddev;
9678 size = sizeof (uint64_t) * 4;
9679 break;
9680
9681 case DTRACEAGG_SUM:
9682 agg->dtag_aggregate = dtrace_aggregate_sum;
9683 break;
9684
9685 default:
9686 goto err;
9687 }
9688
9689 agg->dtag_action.dta_rec.dtrd_size = size;
9690
9691 if (ntuple == 0)
9692 goto err;
9693
9694 /*
9695 * We must make sure that we have enough actions for the n-tuple.
9696 */
9697 for (act = ecb->dte_action_last; act != NULL; act = act->dta_prev) {
9698 if (DTRACEACT_ISAGG(act->dta_kind))
9699 break;
9700
9701 if (--ntuple == 0) {
9702 /*
9703 * This is the action with which our n-tuple begins.
9704 */
9705 agg->dtag_first = act;
9706 goto success;
9707 }
9708 }
9709
9710 /*
9711 * This n-tuple is short by ntuple elements. Return failure.
9712 */
9713 ASSERT(ntuple != 0);
9714 err:
9715 kmem_free(agg, sizeof (dtrace_aggregation_t));
9716 return (NULL);
9717
9718 success:
9719 /*
9720 * If the last action in the tuple has a size of zero, it's actually
9721 * an expression argument for the aggregating action.
9722 */
9723 ASSERT(ecb->dte_action_last != NULL);
9724 act = ecb->dte_action_last;
9725
9726 if (act->dta_kind == DTRACEACT_DIFEXPR) {
9727 ASSERT(act->dta_difo != NULL);
9728
9729 if (act->dta_difo->dtdo_rtype.dtdt_size == 0)
9730 agg->dtag_hasarg = 1;
9731 }
9732
9733 /*
9734 * We need to allocate an id for this aggregation.
9735 */
9736 aggid = (dtrace_aggid_t)(uintptr_t)vmem_alloc(state->dts_aggid_arena, 1,
9737 VM_BESTFIT | VM_SLEEP);
9738
9739 if (aggid - 1 >= state->dts_naggregations) {
9740 dtrace_aggregation_t **oaggs = state->dts_aggregations;
9741 dtrace_aggregation_t **aggs;
9742 int naggs = state->dts_naggregations << 1;
9743 int onaggs = state->dts_naggregations;
9744
9745 ASSERT(aggid == state->dts_naggregations + 1);
9746
9747 if (naggs == 0) {
9748 ASSERT(oaggs == NULL);
9749 naggs = 1;
9750 }
9751
9752 aggs = kmem_zalloc(naggs * sizeof (*aggs), KM_SLEEP);
9753
9754 if (oaggs != NULL) {
9755 bcopy(oaggs, aggs, onaggs * sizeof (*aggs));
9756 kmem_free(oaggs, onaggs * sizeof (*aggs));
9757 }
9758
9759 state->dts_aggregations = aggs;
9760 state->dts_naggregations = naggs;
9761 }
9762
9763 ASSERT(state->dts_aggregations[aggid - 1] == NULL);
9764 state->dts_aggregations[(agg->dtag_id = aggid) - 1] = agg;
9765
9766 frec = &agg->dtag_first->dta_rec;
9767 if (frec->dtrd_alignment < sizeof (dtrace_aggid_t))
9768 frec->dtrd_alignment = sizeof (dtrace_aggid_t);
9769
9770 for (act = agg->dtag_first; act != NULL; act = act->dta_next) {
9771 ASSERT(!act->dta_intuple);
9772 act->dta_intuple = 1;
9773 }
9774
9775 return (&agg->dtag_action);
9776 }
9777
9778 static void
9779 dtrace_ecb_aggregation_destroy(dtrace_ecb_t *ecb, dtrace_action_t *act)
9780 {
9781 dtrace_aggregation_t *agg = (dtrace_aggregation_t *)act;
9782 dtrace_state_t *state = ecb->dte_state;
9783 dtrace_aggid_t aggid = agg->dtag_id;
9784
9785 ASSERT(DTRACEACT_ISAGG(act->dta_kind));
9786 vmem_free(state->dts_aggid_arena, (void *)(uintptr_t)aggid, 1);
9787
9788 ASSERT(state->dts_aggregations[aggid - 1] == agg);
9789 state->dts_aggregations[aggid - 1] = NULL;
9790
9791 kmem_free(agg, sizeof (dtrace_aggregation_t));
9792 }
9793
9794 static int
9795 dtrace_ecb_action_add(dtrace_ecb_t *ecb, dtrace_actdesc_t *desc)
9796 {
9797 dtrace_action_t *action, *last;
9798 dtrace_difo_t *dp = desc->dtad_difo;
9799 uint32_t size = 0, align = sizeof (uint8_t), mask;
9800 uint16_t format = 0;
9801 dtrace_recdesc_t *rec;
9802 dtrace_state_t *state = ecb->dte_state;
9803 dtrace_optval_t *opt = state->dts_options, nframes, strsize;
9804 uint64_t arg = desc->dtad_arg;
9805
9806 ASSERT(MUTEX_HELD(&dtrace_lock));
9807 ASSERT(ecb->dte_action == NULL || ecb->dte_action->dta_refcnt == 1);
9808
9809 if (DTRACEACT_ISAGG(desc->dtad_kind)) {
9810 /*
9811 * If this is an aggregating action, there must be neither
9812 * a speculate nor a commit on the action chain.
9813 */
9814 dtrace_action_t *act;
9815
9816 for (act = ecb->dte_action; act != NULL; act = act->dta_next) {
9817 if (act->dta_kind == DTRACEACT_COMMIT)
9818 return (EINVAL);
9819
9820 if (act->dta_kind == DTRACEACT_SPECULATE)
9821 return (EINVAL);
9822 }
9823
9824 action = dtrace_ecb_aggregation_create(ecb, desc);
9825
9826 if (action == NULL)
9827 return (EINVAL);
9828 } else {
9829 if (DTRACEACT_ISDESTRUCTIVE(desc->dtad_kind) ||
9830 (desc->dtad_kind == DTRACEACT_DIFEXPR &&
9831 dp != NULL && dp->dtdo_destructive)) {
9832 state->dts_destructive = 1;
9833 }
9834
9835 switch (desc->dtad_kind) {
9836 case DTRACEACT_PRINTF:
9837 case DTRACEACT_PRINTA:
9838 case DTRACEACT_SYSTEM:
9839 case DTRACEACT_FREOPEN:
9840 case DTRACEACT_DIFEXPR:
9841 /*
9842 * We know that our arg is a string -- turn it into a
9843 * format.
9844 */
9845 if (arg == NULL) {
9846 ASSERT(desc->dtad_kind == DTRACEACT_PRINTA ||
9847 desc->dtad_kind == DTRACEACT_DIFEXPR);
9848 format = 0;
9849 } else {
9850 ASSERT(arg != NULL);
9851 ASSERT(arg > KERNELBASE);
9852 format = dtrace_format_add(state,
9853 (char *)(uintptr_t)arg);
9854 }
9855
9856 /*FALLTHROUGH*/
9857 case DTRACEACT_LIBACT:
9858 case DTRACEACT_TRACEMEM:
9859 case DTRACEACT_TRACEMEM_DYNSIZE:
9860 if (dp == NULL)
9861 return (EINVAL);
9862
9863 if ((size = dp->dtdo_rtype.dtdt_size) != 0)
9864 break;
9865
9866 if (dp->dtdo_rtype.dtdt_kind == DIF_TYPE_STRING) {
9867 if (!(dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF))
9868 return (EINVAL);
9869
9870 size = opt[DTRACEOPT_STRSIZE];
9871 }
9872
9873 break;
9874
9875 case DTRACEACT_STACK:
9876 if ((nframes = arg) == 0) {
9877 nframes = opt[DTRACEOPT_STACKFRAMES];
9878 ASSERT(nframes > 0);
9879 arg = nframes;
9880 }
9881
9882 size = nframes * sizeof (pc_t);
9883 break;
9884
9885 case DTRACEACT_JSTACK:
9886 if ((strsize = DTRACE_USTACK_STRSIZE(arg)) == 0)
9887 strsize = opt[DTRACEOPT_JSTACKSTRSIZE];
9888
9889 if ((nframes = DTRACE_USTACK_NFRAMES(arg)) == 0)
9890 nframes = opt[DTRACEOPT_JSTACKFRAMES];
9891
9892 arg = DTRACE_USTACK_ARG(nframes, strsize);
9893
9894 /*FALLTHROUGH*/
9895 case DTRACEACT_USTACK:
9896 if (desc->dtad_kind != DTRACEACT_JSTACK &&
9897 (nframes = DTRACE_USTACK_NFRAMES(arg)) == 0) {
9898 strsize = DTRACE_USTACK_STRSIZE(arg);
9899 nframes = opt[DTRACEOPT_USTACKFRAMES];
9900 ASSERT(nframes > 0);
9901 arg = DTRACE_USTACK_ARG(nframes, strsize);
9902 }
9903
9904 /*
9905 * Save a slot for the pid.
9906 */
9907 size = (nframes + 1) * sizeof (uint64_t);
9908 size += DTRACE_USTACK_STRSIZE(arg);
9909 size = P2ROUNDUP(size, (uint32_t)(sizeof (uintptr_t)));
9910
9911 break;
9912
9913 case DTRACEACT_SYM:
9914 case DTRACEACT_MOD:
9915 if (dp == NULL || ((size = dp->dtdo_rtype.dtdt_size) !=
9916 sizeof (uint64_t)) ||
9917 (dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF))
9918 return (EINVAL);
9919 break;
9920
9921 case DTRACEACT_USYM:
9922 case DTRACEACT_UMOD:
9923 case DTRACEACT_UADDR:
9924 if (dp == NULL ||
9925 (dp->dtdo_rtype.dtdt_size != sizeof (uint64_t)) ||
9926 (dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF))
9927 return (EINVAL);
9928
9929 /*
9930 * We have a slot for the pid, plus a slot for the
9931 * argument. To keep things simple (aligned with
9932 * bitness-neutral sizing), we store each as a 64-bit
9933 * quantity.
9934 */
9935 size = 2 * sizeof (uint64_t);
9936 break;
9937
9938 case DTRACEACT_STOP:
9939 case DTRACEACT_BREAKPOINT:
9940 case DTRACEACT_PANIC:
9941 break;
9942
9943 case DTRACEACT_CHILL:
9944 case DTRACEACT_DISCARD:
9945 case DTRACEACT_RAISE:
9946 if (dp == NULL)
9947 return (EINVAL);
9948 break;
9949
9950 case DTRACEACT_EXIT:
9951 if (dp == NULL ||
9952 (size = dp->dtdo_rtype.dtdt_size) != sizeof (int) ||
9953 (dp->dtdo_rtype.dtdt_flags & DIF_TF_BYREF))
9954 return (EINVAL);
9955 break;
9956
9957 case DTRACEACT_SPECULATE:
9958 if (ecb->dte_size > sizeof (dtrace_epid_t))
9959 return (EINVAL);
9960
9961 if (dp == NULL)
9962 return (EINVAL);
9963
9964 state->dts_speculates = 1;
9965 break;
9966
9967 case DTRACEACT_COMMIT: {
9968 dtrace_action_t *act = ecb->dte_action;
9969
9970 for (; act != NULL; act = act->dta_next) {
9971 if (act->dta_kind == DTRACEACT_COMMIT)
9972 return (EINVAL);
9973 }
9974
9975 if (dp == NULL)
9976 return (EINVAL);
9977 break;
9978 }
9979
9980 default:
9981 return (EINVAL);
9982 }
9983
9984 if (size != 0 || desc->dtad_kind == DTRACEACT_SPECULATE) {
9985 /*
9986 * If this is a data-storing action or a speculate,
9987 * we must be sure that there isn't a commit on the
9988 * action chain.
9989 */
9990 dtrace_action_t *act = ecb->dte_action;
9991
9992 for (; act != NULL; act = act->dta_next) {
9993 if (act->dta_kind == DTRACEACT_COMMIT)
9994 return (EINVAL);
9995 }
9996 }
9997
9998 action = kmem_zalloc(sizeof (dtrace_action_t), KM_SLEEP);
9999 action->dta_rec.dtrd_size = size;
10000 }
10001
10002 action->dta_refcnt = 1;
10003 rec = &action->dta_rec;
10004 size = rec->dtrd_size;
10005
10006 for (mask = sizeof (uint64_t) - 1; size != 0 && mask > 0; mask >>= 1) {
10007 if (!(size & mask)) {
10008 align = mask + 1;
10009 break;
10010 }
10011 }
10012
10013 action->dta_kind = desc->dtad_kind;
10014
10015 if ((action->dta_difo = dp) != NULL)
10016 dtrace_difo_hold(dp);
10017
10018 rec->dtrd_action = action->dta_kind;
10019 rec->dtrd_arg = arg;
10020 rec->dtrd_uarg = desc->dtad_uarg;
10021 rec->dtrd_alignment = (uint16_t)align;
10022 rec->dtrd_format = format;
10023
10024 if ((last = ecb->dte_action_last) != NULL) {
10025 ASSERT(ecb->dte_action != NULL);
10026 action->dta_prev = last;
10027 last->dta_next = action;
10028 } else {
10029 ASSERT(ecb->dte_action == NULL);
10030 ecb->dte_action = action;
10031 }
10032
10033 ecb->dte_action_last = action;
10034
10035 return (0);
10036 }
10037
10038 static void
10039 dtrace_ecb_action_remove(dtrace_ecb_t *ecb)
10040 {
10041 dtrace_action_t *act = ecb->dte_action, *next;
10042 dtrace_vstate_t *vstate = &ecb->dte_state->dts_vstate;
10043 dtrace_difo_t *dp;
10044 uint16_t format;
10045
10046 if (act != NULL && act->dta_refcnt > 1) {
10047 ASSERT(act->dta_next == NULL || act->dta_next->dta_refcnt == 1);
10048 act->dta_refcnt--;
10049 } else {
10050 for (; act != NULL; act = next) {
10051 next = act->dta_next;
10052 ASSERT(next != NULL || act == ecb->dte_action_last);
10053 ASSERT(act->dta_refcnt == 1);
10054
10055 if ((format = act->dta_rec.dtrd_format) != 0)
10056 dtrace_format_remove(ecb->dte_state, format);
10057
10058 if ((dp = act->dta_difo) != NULL)
10059 dtrace_difo_release(dp, vstate);
10060
10061 if (DTRACEACT_ISAGG(act->dta_kind)) {
10062 dtrace_ecb_aggregation_destroy(ecb, act);
10063 } else {
10064 kmem_free(act, sizeof (dtrace_action_t));
10065 }
10066 }
10067 }
10068
10069 ecb->dte_action = NULL;
10070 ecb->dte_action_last = NULL;
10071 ecb->dte_size = sizeof (dtrace_epid_t);
10072 }
10073
10074 static void
10075 dtrace_ecb_disable(dtrace_ecb_t *ecb)
10076 {
10077 /*
10078 * We disable the ECB by removing it from its probe.
10079 */
10080 dtrace_ecb_t *pecb, *prev = NULL;
10081 dtrace_probe_t *probe = ecb->dte_probe;
10082
10083 ASSERT(MUTEX_HELD(&dtrace_lock));
10084
10085 if (probe == NULL) {
10086 /*
10087 * This is the NULL probe; there is nothing to disable.
10088 */
10089 return;
10090 }
10091
10092 for (pecb = probe->dtpr_ecb; pecb != NULL; pecb = pecb->dte_next) {
10093 if (pecb == ecb)
10094 break;
10095 prev = pecb;
10096 }
10097
10098 ASSERT(pecb != NULL);
10099
10100 if (prev == NULL) {
10101 probe->dtpr_ecb = ecb->dte_next;
10102 } else {
10103 prev->dte_next = ecb->dte_next;
10104 }
10105
10106 if (ecb == probe->dtpr_ecb_last) {
10107 ASSERT(ecb->dte_next == NULL);
10108 probe->dtpr_ecb_last = prev;
10109 }
10110
10111 /*
10112 * The ECB has been disconnected from the probe; now sync to assure
10113 * that all CPUs have seen the change before returning.
10114 */
10115 dtrace_sync();
10116
10117 if (probe->dtpr_ecb == NULL) {
10118 /*
10119 * That was the last ECB on the probe; clear the predicate
10120 * cache ID for the probe, disable it and sync one more time
10121 * to assure that we'll never hit it again.
10122 */
10123 dtrace_provider_t *prov = probe->dtpr_provider;
10124
10125 ASSERT(ecb->dte_next == NULL);
10126 ASSERT(probe->dtpr_ecb_last == NULL);
10127 probe->dtpr_predcache = DTRACE_CACHEIDNONE;
10128 prov->dtpv_pops.dtps_disable(prov->dtpv_arg,
10129 probe->dtpr_id, probe->dtpr_arg);
10130 dtrace_sync();
10131 } else {
10132 /*
10133 * There is at least one ECB remaining on the probe. If there
10134 * is _exactly_ one, set the probe's predicate cache ID to be
10135 * the predicate cache ID of the remaining ECB.
10136 */
10137 ASSERT(probe->dtpr_ecb_last != NULL);
10138 ASSERT(probe->dtpr_predcache == DTRACE_CACHEIDNONE);
10139
10140 if (probe->dtpr_ecb == probe->dtpr_ecb_last) {
10141 dtrace_predicate_t *p = probe->dtpr_ecb->dte_predicate;
10142
10143 ASSERT(probe->dtpr_ecb->dte_next == NULL);
10144
10145 if (p != NULL)
10146 probe->dtpr_predcache = p->dtp_cacheid;
10147 }
10148
10149 ecb->dte_next = NULL;
10150 }
10151 }
10152
10153 static void
10154 dtrace_ecb_destroy(dtrace_ecb_t *ecb)
10155 {
10156 dtrace_state_t *state = ecb->dte_state;
10157 dtrace_vstate_t *vstate = &state->dts_vstate;
10158 dtrace_predicate_t *pred;
10159 dtrace_epid_t epid = ecb->dte_epid;
10160
10161 ASSERT(MUTEX_HELD(&dtrace_lock));
10162 ASSERT(ecb->dte_next == NULL);
10163 ASSERT(ecb->dte_probe == NULL || ecb->dte_probe->dtpr_ecb != ecb);
10164
10165 if ((pred = ecb->dte_predicate) != NULL)
10166 dtrace_predicate_release(pred, vstate);
10167
10168 dtrace_ecb_action_remove(ecb);
10169
10170 ASSERT(state->dts_ecbs[epid - 1] == ecb);
10171 state->dts_ecbs[epid - 1] = NULL;
10172
10173 kmem_free(ecb, sizeof (dtrace_ecb_t));
10174 }
10175
10176 static dtrace_ecb_t *
10177 dtrace_ecb_create(dtrace_state_t *state, dtrace_probe_t *probe,
10178 dtrace_enabling_t *enab)
10179 {
10180 dtrace_ecb_t *ecb;
10181 dtrace_predicate_t *pred;
10182 dtrace_actdesc_t *act;
10183 dtrace_provider_t *prov;
10184 dtrace_ecbdesc_t *desc = enab->dten_current;
10185
10186 ASSERT(MUTEX_HELD(&dtrace_lock));
10187 ASSERT(state != NULL);
10188
10189 ecb = dtrace_ecb_add(state, probe);
10190 ecb->dte_uarg = desc->dted_uarg;
10191
10192 if ((pred = desc->dted_pred.dtpdd_predicate) != NULL) {
10193 dtrace_predicate_hold(pred);
10194 ecb->dte_predicate = pred;
10195 }
10196
10197 if (probe != NULL) {
10198 /*
10199 * If the provider shows more leg than the consumer is old
10200 * enough to see, we need to enable the appropriate implicit
10201 * predicate bits to prevent the ecb from activating at
10202 * revealing times.
10203 *
10204 * Providers specifying DTRACE_PRIV_USER at register time
10205 * are stating that they need the /proc-style privilege
10206 * model to be enforced, and this is what DTRACE_COND_OWNER
10207 * and DTRACE_COND_ZONEOWNER will then do at probe time.
10208 */
10209 prov = probe->dtpr_provider;
10210 if (!(state->dts_cred.dcr_visible & DTRACE_CRV_ALLPROC) &&
10211 (prov->dtpv_priv.dtpp_flags & DTRACE_PRIV_USER))
10212 ecb->dte_cond |= DTRACE_COND_OWNER;
10213
10214 if (!(state->dts_cred.dcr_visible & DTRACE_CRV_ALLZONE) &&
10215 (prov->dtpv_priv.dtpp_flags & DTRACE_PRIV_USER))
10216 ecb->dte_cond |= DTRACE_COND_ZONEOWNER;
10217
10218 /*
10219 * If the provider shows us kernel innards and the user
10220 * is lacking sufficient privilege, enable the
10221 * DTRACE_COND_USERMODE implicit predicate.
10222 */
10223 if (!(state->dts_cred.dcr_visible & DTRACE_CRV_KERNEL) &&
10224 (prov->dtpv_priv.dtpp_flags & DTRACE_PRIV_KERNEL))
10225 ecb->dte_cond |= DTRACE_COND_USERMODE;
10226 }
10227
10228 if (dtrace_ecb_create_cache != NULL) {
10229 /*
10230 * If we have a cached ecb, we'll use its action list instead
10231 * of creating our own (saving both time and space).
10232 */
10233 dtrace_ecb_t *cached = dtrace_ecb_create_cache;
10234 dtrace_action_t *act = cached->dte_action;
10235
10236 if (act != NULL) {
10237 ASSERT(act->dta_refcnt > 0);
10238 act->dta_refcnt++;
10239 ecb->dte_action = act;
10240 ecb->dte_action_last = cached->dte_action_last;
10241 ecb->dte_needed = cached->dte_needed;
10242 ecb->dte_size = cached->dte_size;
10243 ecb->dte_alignment = cached->dte_alignment;
10244 }
10245
10246 return (ecb);
10247 }
10248
10249 for (act = desc->dted_action; act != NULL; act = act->dtad_next) {
10250 if ((enab->dten_error = dtrace_ecb_action_add(ecb, act)) != 0) {
10251 dtrace_ecb_destroy(ecb);
10252 return (NULL);
10253 }
10254 }
10255
10256 dtrace_ecb_resize(ecb);
10257
10258 return (dtrace_ecb_create_cache = ecb);
10259 }
10260
10261 static int
10262 dtrace_ecb_create_enable(dtrace_probe_t *probe, void *arg)
10263 {
10264 dtrace_ecb_t *ecb;
10265 dtrace_enabling_t *enab = arg;
10266 dtrace_state_t *state = enab->dten_vstate->dtvs_state;
10267
10268 ASSERT(state != NULL);
10269
10270 if (probe != NULL && probe->dtpr_gen < enab->dten_probegen) {
10271 /*
10272 * This probe was created in a generation for which this
10273 * enabling has previously created ECBs; we don't want to
10274 * enable it again, so just kick out.
10275 */
10276 return (DTRACE_MATCH_NEXT);
10277 }
10278
10279 if ((ecb = dtrace_ecb_create(state, probe, enab)) == NULL)
10280 return (DTRACE_MATCH_DONE);
10281
10282 if (dtrace_ecb_enable(ecb) < 0)
10283 return (DTRACE_MATCH_FAIL);
10284
10285 return (DTRACE_MATCH_NEXT);
10286 }
10287
10288 static dtrace_ecb_t *
10289 dtrace_epid2ecb(dtrace_state_t *state, dtrace_epid_t id)
10290 {
10291 dtrace_ecb_t *ecb;
10292
10293 ASSERT(MUTEX_HELD(&dtrace_lock));
10294
10295 if (id == 0 || id > state->dts_necbs)
10296 return (NULL);
10297
10298 ASSERT(state->dts_necbs > 0 && state->dts_ecbs != NULL);
10299 ASSERT((ecb = state->dts_ecbs[id - 1]) == NULL || ecb->dte_epid == id);
10300
10301 return (state->dts_ecbs[id - 1]);
10302 }
10303
10304 static dtrace_aggregation_t *
10305 dtrace_aggid2agg(dtrace_state_t *state, dtrace_aggid_t id)
10306 {
10307 dtrace_aggregation_t *agg;
10308
10309 ASSERT(MUTEX_HELD(&dtrace_lock));
10310
10311 if (id == 0 || id > state->dts_naggregations)
10312 return (NULL);
10313
10314 ASSERT(state->dts_naggregations > 0 && state->dts_aggregations != NULL);
10315 ASSERT((agg = state->dts_aggregations[id - 1]) == NULL ||
10316 agg->dtag_id == id);
10317
10318 return (state->dts_aggregations[id - 1]);
10319 }
10320
10321 /*
10322 * DTrace Buffer Functions
10323 *
10324 * The following functions manipulate DTrace buffers. Most of these functions
10325 * are called in the context of establishing or processing consumer state;
10326 * exceptions are explicitly noted.
10327 */
10328
10329 /*
10330 * Note: called from cross call context. This function switches the two
10331 * buffers on a given CPU. The atomicity of this operation is assured by
10332 * disabling interrupts while the actual switch takes place; the disabling of
10333 * interrupts serializes the execution with any execution of dtrace_probe() on
10334 * the same CPU.
10335 */
10336 static void
10337 dtrace_buffer_switch(dtrace_buffer_t *buf)
10338 {
10339 caddr_t tomax = buf->dtb_tomax;
10340 caddr_t xamot = buf->dtb_xamot;
10341 dtrace_icookie_t cookie;
10342 hrtime_t now = dtrace_gethrtime();
10343
10344 ASSERT(!(buf->dtb_flags & DTRACEBUF_NOSWITCH));
10345 ASSERT(!(buf->dtb_flags & DTRACEBUF_RING));
10346
10347 cookie = dtrace_interrupt_disable();
10348 buf->dtb_tomax = xamot;
10349 buf->dtb_xamot = tomax;
10350 buf->dtb_xamot_drops = buf->dtb_drops;
10351 buf->dtb_xamot_offset = buf->dtb_offset;
10352 buf->dtb_xamot_errors = buf->dtb_errors;
10353 buf->dtb_xamot_flags = buf->dtb_flags;
10354 buf->dtb_offset = 0;
10355 buf->dtb_drops = 0;
10356 buf->dtb_errors = 0;
10357 buf->dtb_flags &= ~(DTRACEBUF_ERROR | DTRACEBUF_DROPPED);
10358 buf->dtb_interval = now - buf->dtb_switched;
10359 buf->dtb_switched = now;
10360 dtrace_interrupt_enable(cookie);
10361 }
10362
10363 /*
10364 * Note: called from cross call context. This function activates a buffer
10365 * on a CPU. As with dtrace_buffer_switch(), the atomicity of the operation
10366 * is guaranteed by the disabling of interrupts.
10367 */
10368 static void
10369 dtrace_buffer_activate(dtrace_state_t *state)
10370 {
10371 dtrace_buffer_t *buf;
10372 dtrace_icookie_t cookie = dtrace_interrupt_disable();
10373
10374 buf = &state->dts_buffer[CPU->cpu_id];
10375
10376 if (buf->dtb_tomax != NULL) {
10377 /*
10378 * We might like to assert that the buffer is marked inactive,
10379 * but this isn't necessarily true: the buffer for the CPU
10380 * that processes the BEGIN probe has its buffer activated
10381 * manually. In this case, we take the (harmless) action
10382 * re-clearing the bit INACTIVE bit.
10383 */
10384 buf->dtb_flags &= ~DTRACEBUF_INACTIVE;
10385 }
10386
10387 dtrace_interrupt_enable(cookie);
10388 }
10389
10390 static int
10391 dtrace_buffer_alloc(dtrace_buffer_t *bufs, size_t size, int flags,
10392 processorid_t cpu, int *factor)
10393 {
10394 cpu_t *cp;
10395 dtrace_buffer_t *buf;
10396 int allocated = 0, desired = 0;
10397
10398 ASSERT(MUTEX_HELD(&cpu_lock));
10399 ASSERT(MUTEX_HELD(&dtrace_lock));
10400
10401 *factor = 1;
10402
10403 if (size > dtrace_nonroot_maxsize &&
10404 !PRIV_POLICY_CHOICE(CRED(), PRIV_ALL, B_FALSE))
10405 return (EFBIG);
10406
10407 cp = cpu_list;
10408
10409 do {
10410 if (cpu != DTRACE_CPUALL && cpu != cp->cpu_id)
10411 continue;
10412
10413 buf = &bufs[cp->cpu_id];
10414
10415 /*
10416 * If there is already a buffer allocated for this CPU, it
10417 * is only possible that this is a DR event. In this case,
10418 * the buffer size must match our specified size.
10419 */
10420 if (buf->dtb_tomax != NULL) {
10421 ASSERT(buf->dtb_size == size);
10422 continue;
10423 }
10424
10425 ASSERT(buf->dtb_xamot == NULL);
10426
10427 if ((buf->dtb_tomax = kmem_zalloc(size,
10428 KM_NOSLEEP | KM_NORMALPRI)) == NULL)
10429 goto err;
10430
10431 buf->dtb_size = size;
10432 buf->dtb_flags = flags;
10433 buf->dtb_offset = 0;
10434 buf->dtb_drops = 0;
10435
10436 if (flags & DTRACEBUF_NOSWITCH)
10437 continue;
10438
10439 if ((buf->dtb_xamot = kmem_zalloc(size,
10440 KM_NOSLEEP | KM_NORMALPRI)) == NULL)
10441 goto err;
10442 } while ((cp = cp->cpu_next) != cpu_list);
10443
10444 return (0);
10445
10446 err:
10447 cp = cpu_list;
10448
10449 do {
10450 if (cpu != DTRACE_CPUALL && cpu != cp->cpu_id)
10451 continue;
10452
10453 buf = &bufs[cp->cpu_id];
10454 desired += 2;
10455
10456 if (buf->dtb_xamot != NULL) {
10457 ASSERT(buf->dtb_tomax != NULL);
10458 ASSERT(buf->dtb_size == size);
10459 kmem_free(buf->dtb_xamot, size);
10460 allocated++;
10461 }
10462
10463 if (buf->dtb_tomax != NULL) {
10464 ASSERT(buf->dtb_size == size);
10465 kmem_free(buf->dtb_tomax, size);
10466 allocated++;
10467 }
10468
10469 buf->dtb_tomax = NULL;
10470 buf->dtb_xamot = NULL;
10471 buf->dtb_size = 0;
10472 } while ((cp = cp->cpu_next) != cpu_list);
10473
10474 *factor = desired / (allocated > 0 ? allocated : 1);
10475
10476 return (ENOMEM);
10477 }
10478
10479 /*
10480 * Note: called from probe context. This function just increments the drop
10481 * count on a buffer. It has been made a function to allow for the
10482 * possibility of understanding the source of mysterious drop counts. (A
10483 * problem for which one may be particularly disappointed that DTrace cannot
10484 * be used to understand DTrace.)
10485 */
10486 static void
10487 dtrace_buffer_drop(dtrace_buffer_t *buf)
10488 {
10489 buf->dtb_drops++;
10490 }
10491
10492 /*
10493 * Note: called from probe context. This function is called to reserve space
10494 * in a buffer. If mstate is non-NULL, sets the scratch base and size in the
10495 * mstate. Returns the new offset in the buffer, or a negative value if an
10496 * error has occurred.
10497 */
10498 static intptr_t
10499 dtrace_buffer_reserve(dtrace_buffer_t *buf, size_t needed, size_t align,
10500 dtrace_state_t *state, dtrace_mstate_t *mstate)
10501 {
10502 intptr_t offs = buf->dtb_offset, soffs;
10503 intptr_t woffs;
10504 caddr_t tomax;
10505 size_t total;
10506
10507 if (buf->dtb_flags & DTRACEBUF_INACTIVE)
10508 return (-1);
10509
10510 if ((tomax = buf->dtb_tomax) == NULL) {
10511 dtrace_buffer_drop(buf);
10512 return (-1);
10513 }
10514
10515 if (!(buf->dtb_flags & (DTRACEBUF_RING | DTRACEBUF_FILL))) {
10516 while (offs & (align - 1)) {
10517 /*
10518 * Assert that our alignment is off by a number which
10519 * is itself sizeof (uint32_t) aligned.
10520 */
10521 ASSERT(!((align - (offs & (align - 1))) &
10522 (sizeof (uint32_t) - 1)));
10523 DTRACE_STORE(uint32_t, tomax, offs, DTRACE_EPIDNONE);
10524 offs += sizeof (uint32_t);
10525 }
10526
10527 if ((soffs = offs + needed) > buf->dtb_size) {
10528 dtrace_buffer_drop(buf);
10529 return (-1);
10530 }
10531
10532 if (mstate == NULL)
10533 return (offs);
10534
10535 mstate->dtms_scratch_base = (uintptr_t)tomax + soffs;
10536 mstate->dtms_scratch_size = buf->dtb_size - soffs;
10537 mstate->dtms_scratch_ptr = mstate->dtms_scratch_base;
10538
10539 return (offs);
10540 }
10541
10542 if (buf->dtb_flags & DTRACEBUF_FILL) {
10543 if (state->dts_activity != DTRACE_ACTIVITY_COOLDOWN &&
10544 (buf->dtb_flags & DTRACEBUF_FULL))
10545 return (-1);
10546 goto out;
10547 }
10548
10549 total = needed + (offs & (align - 1));
10550
10551 /*
10552 * For a ring buffer, life is quite a bit more complicated. Before
10553 * we can store any padding, we need to adjust our wrapping offset.
10554 * (If we've never before wrapped or we're not about to, no adjustment
10555 * is required.)
10556 */
10557 if ((buf->dtb_flags & DTRACEBUF_WRAPPED) ||
10558 offs + total > buf->dtb_size) {
10559 woffs = buf->dtb_xamot_offset;
10560
10561 if (offs + total > buf->dtb_size) {
10562 /*
10563 * We can't fit in the end of the buffer. First, a
10564 * sanity check that we can fit in the buffer at all.
10565 */
10566 if (total > buf->dtb_size) {
10567 dtrace_buffer_drop(buf);
10568 return (-1);
10569 }
10570
10571 /*
10572 * We're going to be storing at the top of the buffer,
10573 * so now we need to deal with the wrapped offset. We
10574 * only reset our wrapped offset to 0 if it is
10575 * currently greater than the current offset. If it
10576 * is less than the current offset, it is because a
10577 * previous allocation induced a wrap -- but the
10578 * allocation didn't subsequently take the space due
10579 * to an error or false predicate evaluation. In this
10580 * case, we'll just leave the wrapped offset alone: if
10581 * the wrapped offset hasn't been advanced far enough
10582 * for this allocation, it will be adjusted in the
10583 * lower loop.
10584 */
10585 if (buf->dtb_flags & DTRACEBUF_WRAPPED) {
10586 if (woffs >= offs)
10587 woffs = 0;
10588 } else {
10589 woffs = 0;
10590 }
10591
10592 /*
10593 * Now we know that we're going to be storing to the
10594 * top of the buffer and that there is room for us
10595 * there. We need to clear the buffer from the current
10596 * offset to the end (there may be old gunk there).
10597 */
10598 while (offs < buf->dtb_size)
10599 tomax[offs++] = 0;
10600
10601 /*
10602 * We need to set our offset to zero. And because we
10603 * are wrapping, we need to set the bit indicating as
10604 * much. We can also adjust our needed space back
10605 * down to the space required by the ECB -- we know
10606 * that the top of the buffer is aligned.
10607 */
10608 offs = 0;
10609 total = needed;
10610 buf->dtb_flags |= DTRACEBUF_WRAPPED;
10611 } else {
10612 /*
10613 * There is room for us in the buffer, so we simply
10614 * need to check the wrapped offset.
10615 */
10616 if (woffs < offs) {
10617 /*
10618 * The wrapped offset is less than the offset.
10619 * This can happen if we allocated buffer space
10620 * that induced a wrap, but then we didn't
10621 * subsequently take the space due to an error
10622 * or false predicate evaluation. This is
10623 * okay; we know that _this_ allocation isn't
10624 * going to induce a wrap. We still can't
10625 * reset the wrapped offset to be zero,
10626 * however: the space may have been trashed in
10627 * the previous failed probe attempt. But at
10628 * least the wrapped offset doesn't need to
10629 * be adjusted at all...
10630 */
10631 goto out;
10632 }
10633 }
10634
10635 while (offs + total > woffs) {
10636 dtrace_epid_t epid = *(uint32_t *)(tomax + woffs);
10637 size_t size;
10638
10639 if (epid == DTRACE_EPIDNONE) {
10640 size = sizeof (uint32_t);
10641 } else {
10642 ASSERT(epid <= state->dts_necbs);
10643 ASSERT(state->dts_ecbs[epid - 1] != NULL);
10644
10645 size = state->dts_ecbs[epid - 1]->dte_size;
10646 }
10647
10648 ASSERT(woffs + size <= buf->dtb_size);
10649 ASSERT(size != 0);
10650
10651 if (woffs + size == buf->dtb_size) {
10652 /*
10653 * We've reached the end of the buffer; we want
10654 * to set the wrapped offset to 0 and break
10655 * out. However, if the offs is 0, then we're
10656 * in a strange edge-condition: the amount of
10657 * space that we want to reserve plus the size
10658 * of the record that we're overwriting is
10659 * greater than the size of the buffer. This
10660 * is problematic because if we reserve the
10661 * space but subsequently don't consume it (due
10662 * to a failed predicate or error) the wrapped
10663 * offset will be 0 -- yet the EPID at offset 0
10664 * will not be committed. This situation is
10665 * relatively easy to deal with: if we're in
10666 * this case, the buffer is indistinguishable
10667 * from one that hasn't wrapped; we need only
10668 * finish the job by clearing the wrapped bit,
10669 * explicitly setting the offset to be 0, and
10670 * zero'ing out the old data in the buffer.
10671 */
10672 if (offs == 0) {
10673 buf->dtb_flags &= ~DTRACEBUF_WRAPPED;
10674 buf->dtb_offset = 0;
10675 woffs = total;
10676
10677 while (woffs < buf->dtb_size)
10678 tomax[woffs++] = 0;
10679 }
10680
10681 woffs = 0;
10682 break;
10683 }
10684
10685 woffs += size;
10686 }
10687
10688 /*
10689 * We have a wrapped offset. It may be that the wrapped offset
10690 * has become zero -- that's okay.
10691 */
10692 buf->dtb_xamot_offset = woffs;
10693 }
10694
10695 out:
10696 /*
10697 * Now we can plow the buffer with any necessary padding.
10698 */
10699 while (offs & (align - 1)) {
10700 /*
10701 * Assert that our alignment is off by a number which
10702 * is itself sizeof (uint32_t) aligned.
10703 */
10704 ASSERT(!((align - (offs & (align - 1))) &
10705 (sizeof (uint32_t) - 1)));
10706 DTRACE_STORE(uint32_t, tomax, offs, DTRACE_EPIDNONE);
10707 offs += sizeof (uint32_t);
10708 }
10709
10710 if (buf->dtb_flags & DTRACEBUF_FILL) {
10711 if (offs + needed > buf->dtb_size - state->dts_reserve) {
10712 buf->dtb_flags |= DTRACEBUF_FULL;
10713 return (-1);
10714 }
10715 }
10716
10717 if (mstate == NULL)
10718 return (offs);
10719
10720 /*
10721 * For ring buffers and fill buffers, the scratch space is always
10722 * the inactive buffer.
10723 */
10724 mstate->dtms_scratch_base = (uintptr_t)buf->dtb_xamot;
10725 mstate->dtms_scratch_size = buf->dtb_size;
10726 mstate->dtms_scratch_ptr = mstate->dtms_scratch_base;
10727
10728 return (offs);
10729 }
10730
10731 static void
10732 dtrace_buffer_polish(dtrace_buffer_t *buf)
10733 {
10734 ASSERT(buf->dtb_flags & DTRACEBUF_RING);
10735 ASSERT(MUTEX_HELD(&dtrace_lock));
10736
10737 if (!(buf->dtb_flags & DTRACEBUF_WRAPPED))
10738 return;
10739
10740 /*
10741 * We need to polish the ring buffer. There are three cases:
10742 *
10743 * - The first (and presumably most common) is that there is no gap
10744 * between the buffer offset and the wrapped offset. In this case,
10745 * there is nothing in the buffer that isn't valid data; we can
10746 * mark the buffer as polished and return.
10747 *
10748 * - The second (less common than the first but still more common
10749 * than the third) is that there is a gap between the buffer offset
10750 * and the wrapped offset, and the wrapped offset is larger than the
10751 * buffer offset. This can happen because of an alignment issue, or
10752 * can happen because of a call to dtrace_buffer_reserve() that
10753 * didn't subsequently consume the buffer space. In this case,
10754 * we need to zero the data from the buffer offset to the wrapped
10755 * offset.
10756 *
10757 * - The third (and least common) is that there is a gap between the
10758 * buffer offset and the wrapped offset, but the wrapped offset is
10759 * _less_ than the buffer offset. This can only happen because a
10760 * call to dtrace_buffer_reserve() induced a wrap, but the space
10761 * was not subsequently consumed. In this case, we need to zero the
10762 * space from the offset to the end of the buffer _and_ from the
10763 * top of the buffer to the wrapped offset.
10764 */
10765 if (buf->dtb_offset < buf->dtb_xamot_offset) {
10766 bzero(buf->dtb_tomax + buf->dtb_offset,
10767 buf->dtb_xamot_offset - buf->dtb_offset);
10768 }
10769
10770 if (buf->dtb_offset > buf->dtb_xamot_offset) {
10771 bzero(buf->dtb_tomax + buf->dtb_offset,
10772 buf->dtb_size - buf->dtb_offset);
10773 bzero(buf->dtb_tomax, buf->dtb_xamot_offset);
10774 }
10775 }
10776
10777 /*
10778 * This routine determines if data generated at the specified time has likely
10779 * been entirely consumed at user-level. This routine is called to determine
10780 * if an ECB on a defunct probe (but for an active enabling) can be safely
10781 * disabled and destroyed.
10782 */
10783 static int
10784 dtrace_buffer_consumed(dtrace_buffer_t *bufs, hrtime_t when)
10785 {
10786 int i;
10787
10788 for (i = 0; i < NCPU; i++) {
10789 dtrace_buffer_t *buf = &bufs[i];
10790
10791 if (buf->dtb_size == 0)
10792 continue;
10793
10794 if (buf->dtb_flags & DTRACEBUF_RING)
10795 return (0);
10796
10797 if (!buf->dtb_switched && buf->dtb_offset != 0)
10798 return (0);
10799
10800 if (buf->dtb_switched - buf->dtb_interval < when)
10801 return (0);
10802 }
10803
10804 return (1);
10805 }
10806
10807 static void
10808 dtrace_buffer_free(dtrace_buffer_t *bufs)
10809 {
10810 int i;
10811
10812 for (i = 0; i < NCPU; i++) {
10813 dtrace_buffer_t *buf = &bufs[i];
10814
10815 if (buf->dtb_tomax == NULL) {
10816 ASSERT(buf->dtb_xamot == NULL);
10817 ASSERT(buf->dtb_size == 0);
10818 continue;
10819 }
10820
10821 if (buf->dtb_xamot != NULL) {
10822 ASSERT(!(buf->dtb_flags & DTRACEBUF_NOSWITCH));
10823 kmem_free(buf->dtb_xamot, buf->dtb_size);
10824 }
10825
10826 kmem_free(buf->dtb_tomax, buf->dtb_size);
10827 buf->dtb_size = 0;
10828 buf->dtb_tomax = NULL;
10829 buf->dtb_xamot = NULL;
10830 }
10831 }
10832
10833 /*
10834 * DTrace Enabling Functions
10835 */
10836 static dtrace_enabling_t *
10837 dtrace_enabling_create(dtrace_vstate_t *vstate)
10838 {
10839 dtrace_enabling_t *enab;
10840
10841 enab = kmem_zalloc(sizeof (dtrace_enabling_t), KM_SLEEP);
10842 enab->dten_vstate = vstate;
10843
10844 return (enab);
10845 }
10846
10847 static void
10848 dtrace_enabling_add(dtrace_enabling_t *enab, dtrace_ecbdesc_t *ecb)
10849 {
10850 dtrace_ecbdesc_t **ndesc;
10851 size_t osize, nsize;
10852
10853 /*
10854 * We can't add to enablings after we've enabled them, or after we've
10855 * retained them.
10856 */
10857 ASSERT(enab->dten_probegen == 0);
10858 ASSERT(enab->dten_next == NULL && enab->dten_prev == NULL);
10859
10860 if (enab->dten_ndesc < enab->dten_maxdesc) {
10861 enab->dten_desc[enab->dten_ndesc++] = ecb;
10862 return;
10863 }
10864
10865 osize = enab->dten_maxdesc * sizeof (dtrace_enabling_t *);
10866
10867 if (enab->dten_maxdesc == 0) {
10868 enab->dten_maxdesc = 1;
10869 } else {
10870 enab->dten_maxdesc <<= 1;
10871 }
10872
10873 ASSERT(enab->dten_ndesc < enab->dten_maxdesc);
10874
10875 nsize = enab->dten_maxdesc * sizeof (dtrace_enabling_t *);
10876 ndesc = kmem_zalloc(nsize, KM_SLEEP);
10877 bcopy(enab->dten_desc, ndesc, osize);
10878 kmem_free(enab->dten_desc, osize);
10879
10880 enab->dten_desc = ndesc;
10881 enab->dten_desc[enab->dten_ndesc++] = ecb;
10882 }
10883
10884 static void
10885 dtrace_enabling_addlike(dtrace_enabling_t *enab, dtrace_ecbdesc_t *ecb,
10886 dtrace_probedesc_t *pd)
10887 {
10888 dtrace_ecbdesc_t *new;
10889 dtrace_predicate_t *pred;
10890 dtrace_actdesc_t *act;
10891
10892 /*
10893 * We're going to create a new ECB description that matches the
10894 * specified ECB in every way, but has the specified probe description.
10895 */
10896 new = kmem_zalloc(sizeof (dtrace_ecbdesc_t), KM_SLEEP);
10897
10898 if ((pred = ecb->dted_pred.dtpdd_predicate) != NULL)
10899 dtrace_predicate_hold(pred);
10900
10901 for (act = ecb->dted_action; act != NULL; act = act->dtad_next)
10902 dtrace_actdesc_hold(act);
10903
10904 new->dted_action = ecb->dted_action;
10905 new->dted_pred = ecb->dted_pred;
10906 new->dted_probe = *pd;
10907 new->dted_uarg = ecb->dted_uarg;
10908
10909 dtrace_enabling_add(enab, new);
10910 }
10911
10912 static void
10913 dtrace_enabling_dump(dtrace_enabling_t *enab)
10914 {
10915 int i;
10916
10917 for (i = 0; i < enab->dten_ndesc; i++) {
10918 dtrace_probedesc_t *desc = &enab->dten_desc[i]->dted_probe;
10919
10920 cmn_err(CE_NOTE, "enabling probe %d (%s:%s:%s:%s)", i,
10921 desc->dtpd_provider, desc->dtpd_mod,
10922 desc->dtpd_func, desc->dtpd_name);
10923 }
10924 }
10925
10926 static void
10927 dtrace_enabling_destroy(dtrace_enabling_t *enab)
10928 {
10929 int i;
10930 dtrace_ecbdesc_t *ep;
10931 dtrace_vstate_t *vstate = enab->dten_vstate;
10932
10933 ASSERT(MUTEX_HELD(&dtrace_lock));
10934
10935 for (i = 0; i < enab->dten_ndesc; i++) {
10936 dtrace_actdesc_t *act, *next;
10937 dtrace_predicate_t *pred;
10938
10939 ep = enab->dten_desc[i];
10940
10941 if ((pred = ep->dted_pred.dtpdd_predicate) != NULL)
10942 dtrace_predicate_release(pred, vstate);
10943
10944 for (act = ep->dted_action; act != NULL; act = next) {
10945 next = act->dtad_next;
10946 dtrace_actdesc_release(act, vstate);
10947 }
10948
10949 kmem_free(ep, sizeof (dtrace_ecbdesc_t));
10950 }
10951
10952 kmem_free(enab->dten_desc,
10953 enab->dten_maxdesc * sizeof (dtrace_enabling_t *));
10954
10955 /*
10956 * If this was a retained enabling, decrement the dts_nretained count
10957 * and take it off of the dtrace_retained list.
10958 */
10959 if (enab->dten_prev != NULL || enab->dten_next != NULL ||
10960 dtrace_retained == enab) {
10961 ASSERT(enab->dten_vstate->dtvs_state != NULL);
10962 ASSERT(enab->dten_vstate->dtvs_state->dts_nretained > 0);
10963 enab->dten_vstate->dtvs_state->dts_nretained--;
10964 dtrace_retained_gen++;
10965 }
10966
10967 if (enab->dten_prev == NULL) {
10968 if (dtrace_retained == enab) {
10969 dtrace_retained = enab->dten_next;
10970
10971 if (dtrace_retained != NULL)
10972 dtrace_retained->dten_prev = NULL;
10973 }
10974 } else {
10975 ASSERT(enab != dtrace_retained);
10976 ASSERT(dtrace_retained != NULL);
10977 enab->dten_prev->dten_next = enab->dten_next;
10978 }
10979
10980 if (enab->dten_next != NULL) {
10981 ASSERT(dtrace_retained != NULL);
10982 enab->dten_next->dten_prev = enab->dten_prev;
10983 }
10984
10985 kmem_free(enab, sizeof (dtrace_enabling_t));
10986 }
10987
10988 static int
10989 dtrace_enabling_retain(dtrace_enabling_t *enab)
10990 {
10991 dtrace_state_t *state;
10992
10993 ASSERT(MUTEX_HELD(&dtrace_lock));
10994 ASSERT(enab->dten_next == NULL && enab->dten_prev == NULL);
10995 ASSERT(enab->dten_vstate != NULL);
10996
10997 state = enab->dten_vstate->dtvs_state;
10998 ASSERT(state != NULL);
10999
11000 /*
11001 * We only allow each state to retain dtrace_retain_max enablings.
11002 */
11003 if (state->dts_nretained >= dtrace_retain_max)
11004 return (ENOSPC);
11005
11006 state->dts_nretained++;
11007 dtrace_retained_gen++;
11008
11009 if (dtrace_retained == NULL) {
11010 dtrace_retained = enab;
11011 return (0);
11012 }
11013
11014 enab->dten_next = dtrace_retained;
11015 dtrace_retained->dten_prev = enab;
11016 dtrace_retained = enab;
11017
11018 return (0);
11019 }
11020
11021 static int
11022 dtrace_enabling_replicate(dtrace_state_t *state, dtrace_probedesc_t *match,
11023 dtrace_probedesc_t *create)
11024 {
11025 dtrace_enabling_t *new, *enab;
11026 int found = 0, err = ENOENT;
11027
11028 ASSERT(MUTEX_HELD(&dtrace_lock));
11029 ASSERT(strlen(match->dtpd_provider) < DTRACE_PROVNAMELEN);
11030 ASSERT(strlen(match->dtpd_mod) < DTRACE_MODNAMELEN);
11031 ASSERT(strlen(match->dtpd_func) < DTRACE_FUNCNAMELEN);
11032 ASSERT(strlen(match->dtpd_name) < DTRACE_NAMELEN);
11033
11034 new = dtrace_enabling_create(&state->dts_vstate);
11035
11036 /*
11037 * Iterate over all retained enablings, looking for enablings that
11038 * match the specified state.
11039 */
11040 for (enab = dtrace_retained; enab != NULL; enab = enab->dten_next) {
11041 int i;
11042
11043 /*
11044 * dtvs_state can only be NULL for helper enablings -- and
11045 * helper enablings can't be retained.
11046 */
11047 ASSERT(enab->dten_vstate->dtvs_state != NULL);
11048
11049 if (enab->dten_vstate->dtvs_state != state)
11050 continue;
11051
11052 /*
11053 * Now iterate over each probe description; we're looking for
11054 * an exact match to the specified probe description.
11055 */
11056 for (i = 0; i < enab->dten_ndesc; i++) {
11057 dtrace_ecbdesc_t *ep = enab->dten_desc[i];
11058 dtrace_probedesc_t *pd = &ep->dted_probe;
11059
11060 if (strcmp(pd->dtpd_provider, match->dtpd_provider))
11061 continue;
11062
11063 if (strcmp(pd->dtpd_mod, match->dtpd_mod))
11064 continue;
11065
11066 if (strcmp(pd->dtpd_func, match->dtpd_func))
11067 continue;
11068
11069 if (strcmp(pd->dtpd_name, match->dtpd_name))
11070 continue;
11071
11072 /*
11073 * We have a winning probe! Add it to our growing
11074 * enabling.
11075 */
11076 found = 1;
11077 dtrace_enabling_addlike(new, ep, create);
11078 }
11079 }
11080
11081 if (!found || (err = dtrace_enabling_retain(new)) != 0) {
11082 dtrace_enabling_destroy(new);
11083 return (err);
11084 }
11085
11086 return (0);
11087 }
11088
11089 static void
11090 dtrace_enabling_retract(dtrace_state_t *state)
11091 {
11092 dtrace_enabling_t *enab, *next;
11093
11094 ASSERT(MUTEX_HELD(&dtrace_lock));
11095
11096 /*
11097 * Iterate over all retained enablings, destroy the enablings retained
11098 * for the specified state.
11099 */
11100 for (enab = dtrace_retained; enab != NULL; enab = next) {
11101 next = enab->dten_next;
11102
11103 /*
11104 * dtvs_state can only be NULL for helper enablings -- and
11105 * helper enablings can't be retained.
11106 */
11107 ASSERT(enab->dten_vstate->dtvs_state != NULL);
11108
11109 if (enab->dten_vstate->dtvs_state == state) {
11110 ASSERT(state->dts_nretained > 0);
11111 dtrace_enabling_destroy(enab);
11112 }
11113 }
11114
11115 ASSERT(state->dts_nretained == 0);
11116 }
11117
11118 static int
11119 dtrace_enabling_match(dtrace_enabling_t *enab, int *nmatched)
11120 {
11121 int i = 0;
11122 int total_matched = 0, matched = 0;
11123
11124 ASSERT(MUTEX_HELD(&cpu_lock));
11125 ASSERT(MUTEX_HELD(&dtrace_lock));
11126
11127 for (i = 0; i < enab->dten_ndesc; i++) {
11128 dtrace_ecbdesc_t *ep = enab->dten_desc[i];
11129
11130 enab->dten_current = ep;
11131 enab->dten_error = 0;
11132
11133 /*
11134 * If a provider failed to enable a probe then get out and
11135 * let the consumer know we failed.
11136 */
11137 if ((matched = dtrace_probe_enable(&ep->dted_probe, enab)) < 0)
11138 return (EBUSY);
11139
11140 total_matched += matched;
11141
11142 if (enab->dten_error != 0) {
11143 /*
11144 * If we get an error half-way through enabling the
11145 * probes, we kick out -- perhaps with some number of
11146 * them enabled. Leaving enabled probes enabled may
11147 * be slightly confusing for user-level, but we expect
11148 * that no one will attempt to actually drive on in
11149 * the face of such errors. If this is an anonymous
11150 * enabling (indicated with a NULL nmatched pointer),
11151 * we cmn_err() a message. We aren't expecting to
11152 * get such an error -- such as it can exist at all,
11153 * it would be a result of corrupted DOF in the driver
11154 * properties.
11155 */
11156 if (nmatched == NULL) {
11157 cmn_err(CE_WARN, "dtrace_enabling_match() "
11158 "error on %p: %d", (void *)ep,
11159 enab->dten_error);
11160 }
11161
11162 return (enab->dten_error);
11163 }
11164 }
11165
11166 enab->dten_probegen = dtrace_probegen;
11167 if (nmatched != NULL)
11168 *nmatched = total_matched;
11169
11170 return (0);
11171 }
11172
11173 static void
11174 dtrace_enabling_matchall(void)
11175 {
11176 dtrace_enabling_t *enab;
11177
11178 mutex_enter(&cpu_lock);
11179 mutex_enter(&dtrace_lock);
11180
11181 /*
11182 * Iterate over all retained enablings to see if any probes match
11183 * against them. We only perform this operation on enablings for which
11184 * we have sufficient permissions by virtue of being in the global zone
11185 * or in the same zone as the DTrace client. Because we can be called
11186 * after dtrace_detach() has been called, we cannot assert that there
11187 * are retained enablings. We can safely load from dtrace_retained,
11188 * however: the taskq_destroy() at the end of dtrace_detach() will
11189 * block pending our completion.
11190 */
11191 for (enab = dtrace_retained; enab != NULL; enab = enab->dten_next) {
11192 dtrace_cred_t *dcr = &enab->dten_vstate->dtvs_state->dts_cred;
11193 cred_t *cr = dcr->dcr_cred;
11194 zoneid_t zone = cr != NULL ? crgetzoneid(cr) : 0;
11195
11196 if ((dcr->dcr_visible & DTRACE_CRV_ALLZONE) || (cr != NULL &&
11197 (zone == GLOBAL_ZONEID || getzoneid() == zone)))
11198 (void) dtrace_enabling_match(enab, NULL);
11199 }
11200
11201 mutex_exit(&dtrace_lock);
11202 mutex_exit(&cpu_lock);
11203 }
11204
11205 /*
11206 * If an enabling is to be enabled without having matched probes (that is, if
11207 * dtrace_state_go() is to be called on the underlying dtrace_state_t), the
11208 * enabling must be _primed_ by creating an ECB for every ECB description.
11209 * This must be done to assure that we know the number of speculations, the
11210 * number of aggregations, the minimum buffer size needed, etc. before we
11211 * transition out of DTRACE_ACTIVITY_INACTIVE. To do this without actually
11212 * enabling any probes, we create ECBs for every ECB decription, but with a
11213 * NULL probe -- which is exactly what this function does.
11214 */
11215 static void
11216 dtrace_enabling_prime(dtrace_state_t *state)
11217 {
11218 dtrace_enabling_t *enab;
11219 int i;
11220
11221 for (enab = dtrace_retained; enab != NULL; enab = enab->dten_next) {
11222 ASSERT(enab->dten_vstate->dtvs_state != NULL);
11223
11224 if (enab->dten_vstate->dtvs_state != state)
11225 continue;
11226
11227 /*
11228 * We don't want to prime an enabling more than once, lest
11229 * we allow a malicious user to induce resource exhaustion.
11230 * (The ECBs that result from priming an enabling aren't
11231 * leaked -- but they also aren't deallocated until the
11232 * consumer state is destroyed.)
11233 */
11234 if (enab->dten_primed)
11235 continue;
11236
11237 for (i = 0; i < enab->dten_ndesc; i++) {
11238 enab->dten_current = enab->dten_desc[i];
11239 (void) dtrace_probe_enable(NULL, enab);
11240 }
11241
11242 enab->dten_primed = 1;
11243 }
11244 }
11245
11246 /*
11247 * Called to indicate that probes should be provided due to retained
11248 * enablings. This is implemented in terms of dtrace_probe_provide(), but it
11249 * must take an initial lap through the enabling calling the dtps_provide()
11250 * entry point explicitly to allow for autocreated probes.
11251 */
11252 static void
11253 dtrace_enabling_provide(dtrace_provider_t *prv)
11254 {
11255 int i, all = 0;
11256 dtrace_probedesc_t desc;
11257 dtrace_genid_t gen;
11258
11259 ASSERT(MUTEX_HELD(&dtrace_lock));
11260 ASSERT(MUTEX_HELD(&dtrace_provider_lock));
11261
11262 if (prv == NULL) {
11263 all = 1;
11264 prv = dtrace_provider;
11265 }
11266
11267 do {
11268 dtrace_enabling_t *enab;
11269 void *parg = prv->dtpv_arg;
11270
11271 retry:
11272 gen = dtrace_retained_gen;
11273 for (enab = dtrace_retained; enab != NULL;
11274 enab = enab->dten_next) {
11275 for (i = 0; i < enab->dten_ndesc; i++) {
11276 desc = enab->dten_desc[i]->dted_probe;
11277 mutex_exit(&dtrace_lock);
11278 prv->dtpv_pops.dtps_provide(parg, &desc);
11279 mutex_enter(&dtrace_lock);
11280 /*
11281 * Process the retained enablings again if
11282 * they have changed while we weren't holding
11283 * dtrace_lock.
11284 */
11285 if (gen != dtrace_retained_gen)
11286 goto retry;
11287 }
11288 }
11289 } while (all && (prv = prv->dtpv_next) != NULL);
11290
11291 mutex_exit(&dtrace_lock);
11292 dtrace_probe_provide(NULL, all ? NULL : prv);
11293 mutex_enter(&dtrace_lock);
11294 }
11295
11296 /*
11297 * Called to reap ECBs that are attached to probes from defunct providers.
11298 */
11299 static void
11300 dtrace_enabling_reap(void)
11301 {
11302 dtrace_provider_t *prov;
11303 dtrace_probe_t *probe;
11304 dtrace_ecb_t *ecb;
11305 hrtime_t when;
11306 int i;
11307
11308 mutex_enter(&cpu_lock);
11309 mutex_enter(&dtrace_lock);
11310
11311 for (i = 0; i < dtrace_nprobes; i++) {
11312 if ((probe = dtrace_probes[i]) == NULL)
11313 continue;
11314
11315 if (probe->dtpr_ecb == NULL)
11316 continue;
11317
11318 prov = probe->dtpr_provider;
11319
11320 if ((when = prov->dtpv_defunct) == 0)
11321 continue;
11322
11323 /*
11324 * We have ECBs on a defunct provider: we want to reap these
11325 * ECBs to allow the provider to unregister. The destruction
11326 * of these ECBs must be done carefully: if we destroy the ECB
11327 * and the consumer later wishes to consume an EPID that
11328 * corresponds to the destroyed ECB (and if the EPID metadata
11329 * has not been previously consumed), the consumer will abort
11330 * processing on the unknown EPID. To reduce (but not, sadly,
11331 * eliminate) the possibility of this, we will only destroy an
11332 * ECB for a defunct provider if, for the state that
11333 * corresponds to the ECB:
11334 *
11335 * (a) There is no speculative tracing (which can effectively
11336 * cache an EPID for an arbitrary amount of time).
11337 *
11338 * (b) The principal buffers have been switched twice since the
11339 * provider became defunct.
11340 *
11341 * (c) The aggregation buffers are of zero size or have been
11342 * switched twice since the provider became defunct.
11343 *
11344 * We use dts_speculates to determine (a) and call a function
11345 * (dtrace_buffer_consumed()) to determine (b) and (c). Note
11346 * that as soon as we've been unable to destroy one of the ECBs
11347 * associated with the probe, we quit trying -- reaping is only
11348 * fruitful in as much as we can destroy all ECBs associated
11349 * with the defunct provider's probes.
11350 */
11351 while ((ecb = probe->dtpr_ecb) != NULL) {
11352 dtrace_state_t *state = ecb->dte_state;
11353 dtrace_buffer_t *buf = state->dts_buffer;
11354 dtrace_buffer_t *aggbuf = state->dts_aggbuffer;
11355
11356 if (state->dts_speculates)
11357 break;
11358
11359 if (!dtrace_buffer_consumed(buf, when))
11360 break;
11361
11362 if (!dtrace_buffer_consumed(aggbuf, when))
11363 break;
11364
11365 dtrace_ecb_disable(ecb);
11366 ASSERT(probe->dtpr_ecb != ecb);
11367 dtrace_ecb_destroy(ecb);
11368 }
11369 }
11370
11371 mutex_exit(&dtrace_lock);
11372 mutex_exit(&cpu_lock);
11373 }
11374
11375 /*
11376 * DTrace DOF Functions
11377 */
11378 /*ARGSUSED*/
11379 static void
11380 dtrace_dof_error(dof_hdr_t *dof, const char *str)
11381 {
11382 if (dtrace_err_verbose)
11383 cmn_err(CE_WARN, "failed to process DOF: %s", str);
11384
11385 #ifdef DTRACE_ERRDEBUG
11386 dtrace_errdebug(str);
11387 #endif
11388 }
11389
11390 /*
11391 * Create DOF out of a currently enabled state. Right now, we only create
11392 * DOF containing the run-time options -- but this could be expanded to create
11393 * complete DOF representing the enabled state.
11394 */
11395 static dof_hdr_t *
11396 dtrace_dof_create(dtrace_state_t *state)
11397 {
11398 dof_hdr_t *dof;
11399 dof_sec_t *sec;
11400 dof_optdesc_t *opt;
11401 int i, len = sizeof (dof_hdr_t) +
11402 roundup(sizeof (dof_sec_t), sizeof (uint64_t)) +
11403 sizeof (dof_optdesc_t) * DTRACEOPT_MAX;
11404
11405 ASSERT(MUTEX_HELD(&dtrace_lock));
11406
11407 dof = kmem_zalloc(len, KM_SLEEP);
11408 dof->dofh_ident[DOF_ID_MAG0] = DOF_MAG_MAG0;
11409 dof->dofh_ident[DOF_ID_MAG1] = DOF_MAG_MAG1;
11410 dof->dofh_ident[DOF_ID_MAG2] = DOF_MAG_MAG2;
11411 dof->dofh_ident[DOF_ID_MAG3] = DOF_MAG_MAG3;
11412
11413 dof->dofh_ident[DOF_ID_MODEL] = DOF_MODEL_NATIVE;
11414 dof->dofh_ident[DOF_ID_ENCODING] = DOF_ENCODE_NATIVE;
11415 dof->dofh_ident[DOF_ID_VERSION] = DOF_VERSION;
11416 dof->dofh_ident[DOF_ID_DIFVERS] = DIF_VERSION;
11417 dof->dofh_ident[DOF_ID_DIFIREG] = DIF_DIR_NREGS;
11418 dof->dofh_ident[DOF_ID_DIFTREG] = DIF_DTR_NREGS;
11419
11420 dof->dofh_flags = 0;
11421 dof->dofh_hdrsize = sizeof (dof_hdr_t);
11422 dof->dofh_secsize = sizeof (dof_sec_t);
11423 dof->dofh_secnum = 1; /* only DOF_SECT_OPTDESC */
11424 dof->dofh_secoff = sizeof (dof_hdr_t);
11425 dof->dofh_loadsz = len;
11426 dof->dofh_filesz = len;
11427 dof->dofh_pad = 0;
11428
11429 /*
11430 * Fill in the option section header...
11431 */
11432 sec = (dof_sec_t *)((uintptr_t)dof + sizeof (dof_hdr_t));
11433 sec->dofs_type = DOF_SECT_OPTDESC;
11434 sec->dofs_align = sizeof (uint64_t);
11435 sec->dofs_flags = DOF_SECF_LOAD;
11436 sec->dofs_entsize = sizeof (dof_optdesc_t);
11437
11438 opt = (dof_optdesc_t *)((uintptr_t)sec +
11439 roundup(sizeof (dof_sec_t), sizeof (uint64_t)));
11440
11441 sec->dofs_offset = (uintptr_t)opt - (uintptr_t)dof;
11442 sec->dofs_size = sizeof (dof_optdesc_t) * DTRACEOPT_MAX;
11443
11444 for (i = 0; i < DTRACEOPT_MAX; i++) {
11445 opt[i].dofo_option = i;
11446 opt[i].dofo_strtab = DOF_SECIDX_NONE;
11447 opt[i].dofo_value = state->dts_options[i];
11448 }
11449
11450 return (dof);
11451 }
11452
11453 static dof_hdr_t *
11454 dtrace_dof_copyin(uintptr_t uarg, int *errp)
11455 {
11456 dof_hdr_t hdr, *dof;
11457
11458 ASSERT(!MUTEX_HELD(&dtrace_lock));
11459
11460 /*
11461 * First, we're going to copyin() the sizeof (dof_hdr_t).
11462 */
11463 if (copyin((void *)uarg, &hdr, sizeof (hdr)) != 0) {
11464 dtrace_dof_error(NULL, "failed to copyin DOF header");
11465 *errp = EFAULT;
11466 return (NULL);
11467 }
11468
11469 /*
11470 * Now we'll allocate the entire DOF and copy it in -- provided
11471 * that the length isn't outrageous.
11472 */
11473 if (hdr.dofh_loadsz >= dtrace_dof_maxsize) {
11474 dtrace_dof_error(&hdr, "load size exceeds maximum");
11475 *errp = E2BIG;
11476 return (NULL);
11477 }
11478
11479 if (hdr.dofh_loadsz < sizeof (hdr)) {
11480 dtrace_dof_error(&hdr, "invalid load size");
11481 *errp = EINVAL;
11482 return (NULL);
11483 }
11484
11485 dof = kmem_alloc(hdr.dofh_loadsz, KM_SLEEP);
11486
11487 if (copyin((void *)uarg, dof, hdr.dofh_loadsz) != 0 ||
11488 dof->dofh_loadsz != hdr.dofh_loadsz) {
11489 kmem_free(dof, hdr.dofh_loadsz);
11490 *errp = EFAULT;
11491 return (NULL);
11492 }
11493
11494 return (dof);
11495 }
11496
11497 static dof_hdr_t *
11498 dtrace_dof_property(const char *name)
11499 {
11500 uchar_t *buf;
11501 uint64_t loadsz;
11502 unsigned int len, i;
11503 dof_hdr_t *dof;
11504
11505 /*
11506 * Unfortunately, array of values in .conf files are always (and
11507 * only) interpreted to be integer arrays. We must read our DOF
11508 * as an integer array, and then squeeze it into a byte array.
11509 */
11510 if (ddi_prop_lookup_int_array(DDI_DEV_T_ANY, dtrace_devi, 0,
11511 (char *)name, (int **)&buf, &len) != DDI_PROP_SUCCESS)
11512 return (NULL);
11513
11514 for (i = 0; i < len; i++)
11515 buf[i] = (uchar_t)(((int *)buf)[i]);
11516
11517 if (len < sizeof (dof_hdr_t)) {
11518 ddi_prop_free(buf);
11519 dtrace_dof_error(NULL, "truncated header");
11520 return (NULL);
11521 }
11522
11523 if (len < (loadsz = ((dof_hdr_t *)buf)->dofh_loadsz)) {
11524 ddi_prop_free(buf);
11525 dtrace_dof_error(NULL, "truncated DOF");
11526 return (NULL);
11527 }
11528
11529 if (loadsz >= dtrace_dof_maxsize) {
11530 ddi_prop_free(buf);
11531 dtrace_dof_error(NULL, "oversized DOF");
11532 return (NULL);
11533 }
11534
11535 dof = kmem_alloc(loadsz, KM_SLEEP);
11536 bcopy(buf, dof, loadsz);
11537 ddi_prop_free(buf);
11538
11539 return (dof);
11540 }
11541
11542 static void
11543 dtrace_dof_destroy(dof_hdr_t *dof)
11544 {
11545 kmem_free(dof, dof->dofh_loadsz);
11546 }
11547
11548 /*
11549 * Return the dof_sec_t pointer corresponding to a given section index. If the
11550 * index is not valid, dtrace_dof_error() is called and NULL is returned. If
11551 * a type other than DOF_SECT_NONE is specified, the header is checked against
11552 * this type and NULL is returned if the types do not match.
11553 */
11554 static dof_sec_t *
11555 dtrace_dof_sect(dof_hdr_t *dof, uint32_t type, dof_secidx_t i)
11556 {
11557 dof_sec_t *sec = (dof_sec_t *)(uintptr_t)
11558 ((uintptr_t)dof + dof->dofh_secoff + i * dof->dofh_secsize);
11559
11560 if (i >= dof->dofh_secnum) {
11561 dtrace_dof_error(dof, "referenced section index is invalid");
11562 return (NULL);
11563 }
11564
11565 if (!(sec->dofs_flags & DOF_SECF_LOAD)) {
11566 dtrace_dof_error(dof, "referenced section is not loadable");
11567 return (NULL);
11568 }
11569
11570 if (type != DOF_SECT_NONE && type != sec->dofs_type) {
11571 dtrace_dof_error(dof, "referenced section is the wrong type");
11572 return (NULL);
11573 }
11574
11575 return (sec);
11576 }
11577
11578 static dtrace_probedesc_t *
11579 dtrace_dof_probedesc(dof_hdr_t *dof, dof_sec_t *sec, dtrace_probedesc_t *desc)
11580 {
11581 dof_probedesc_t *probe;
11582 dof_sec_t *strtab;
11583 uintptr_t daddr = (uintptr_t)dof;
11584 uintptr_t str;
11585 size_t size;
11586
11587 if (sec->dofs_type != DOF_SECT_PROBEDESC) {
11588 dtrace_dof_error(dof, "invalid probe section");
11589 return (NULL);
11590 }
11591
11592 if (sec->dofs_align != sizeof (dof_secidx_t)) {
11593 dtrace_dof_error(dof, "bad alignment in probe description");
11594 return (NULL);
11595 }
11596
11597 if (sec->dofs_offset + sizeof (dof_probedesc_t) > dof->dofh_loadsz) {
11598 dtrace_dof_error(dof, "truncated probe description");
11599 return (NULL);
11600 }
11601
11602 probe = (dof_probedesc_t *)(uintptr_t)(daddr + sec->dofs_offset);
11603 strtab = dtrace_dof_sect(dof, DOF_SECT_STRTAB, probe->dofp_strtab);
11604
11605 if (strtab == NULL)
11606 return (NULL);
11607
11608 str = daddr + strtab->dofs_offset;
11609 size = strtab->dofs_size;
11610
11611 if (probe->dofp_provider >= strtab->dofs_size) {
11612 dtrace_dof_error(dof, "corrupt probe provider");
11613 return (NULL);
11614 }
11615
11616 (void) strncpy(desc->dtpd_provider,
11617 (char *)(str + probe->dofp_provider),
11618 MIN(DTRACE_PROVNAMELEN - 1, size - probe->dofp_provider));
11619
11620 if (probe->dofp_mod >= strtab->dofs_size) {
11621 dtrace_dof_error(dof, "corrupt probe module");
11622 return (NULL);
11623 }
11624
11625 (void) strncpy(desc->dtpd_mod, (char *)(str + probe->dofp_mod),
11626 MIN(DTRACE_MODNAMELEN - 1, size - probe->dofp_mod));
11627
11628 if (probe->dofp_func >= strtab->dofs_size) {
11629 dtrace_dof_error(dof, "corrupt probe function");
11630 return (NULL);
11631 }
11632
11633 (void) strncpy(desc->dtpd_func, (char *)(str + probe->dofp_func),
11634 MIN(DTRACE_FUNCNAMELEN - 1, size - probe->dofp_func));
11635
11636 if (probe->dofp_name >= strtab->dofs_size) {
11637 dtrace_dof_error(dof, "corrupt probe name");
11638 return (NULL);
11639 }
11640
11641 (void) strncpy(desc->dtpd_name, (char *)(str + probe->dofp_name),
11642 MIN(DTRACE_NAMELEN - 1, size - probe->dofp_name));
11643
11644 return (desc);
11645 }
11646
11647 static dtrace_difo_t *
11648 dtrace_dof_difo(dof_hdr_t *dof, dof_sec_t *sec, dtrace_vstate_t *vstate,
11649 cred_t *cr)
11650 {
11651 dtrace_difo_t *dp;
11652 size_t ttl = 0;
11653 dof_difohdr_t *dofd;
11654 uintptr_t daddr = (uintptr_t)dof;
11655 size_t max = dtrace_difo_maxsize;
11656 int i, l, n;
11657
11658 static const struct {
11659 int section;
11660 int bufoffs;
11661 int lenoffs;
11662 int entsize;
11663 int align;
11664 const char *msg;
11665 } difo[] = {
11666 { DOF_SECT_DIF, offsetof(dtrace_difo_t, dtdo_buf),
11667 offsetof(dtrace_difo_t, dtdo_len), sizeof (dif_instr_t),
11668 sizeof (dif_instr_t), "multiple DIF sections" },
11669
11670 { DOF_SECT_INTTAB, offsetof(dtrace_difo_t, dtdo_inttab),
11671 offsetof(dtrace_difo_t, dtdo_intlen), sizeof (uint64_t),
11672 sizeof (uint64_t), "multiple integer tables" },
11673
11674 { DOF_SECT_STRTAB, offsetof(dtrace_difo_t, dtdo_strtab),
11675 offsetof(dtrace_difo_t, dtdo_strlen), 0,
11676 sizeof (char), "multiple string tables" },
11677
11678 { DOF_SECT_VARTAB, offsetof(dtrace_difo_t, dtdo_vartab),
11679 offsetof(dtrace_difo_t, dtdo_varlen), sizeof (dtrace_difv_t),
11680 sizeof (uint_t), "multiple variable tables" },
11681
11682 { DOF_SECT_NONE, 0, 0, 0, NULL }
11683 };
11684
11685 if (sec->dofs_type != DOF_SECT_DIFOHDR) {
11686 dtrace_dof_error(dof, "invalid DIFO header section");
11687 return (NULL);
11688 }
11689
11690 if (sec->dofs_align != sizeof (dof_secidx_t)) {
11691 dtrace_dof_error(dof, "bad alignment in DIFO header");
11692 return (NULL);
11693 }
11694
11695 if (sec->dofs_size < sizeof (dof_difohdr_t) ||
11696 sec->dofs_size % sizeof (dof_secidx_t)) {
11697 dtrace_dof_error(dof, "bad size in DIFO header");
11698 return (NULL);
11699 }
11700
11701 dofd = (dof_difohdr_t *)(uintptr_t)(daddr + sec->dofs_offset);
11702 n = (sec->dofs_size - sizeof (*dofd)) / sizeof (dof_secidx_t) + 1;
11703
11704 dp = kmem_zalloc(sizeof (dtrace_difo_t), KM_SLEEP);
11705 dp->dtdo_rtype = dofd->dofd_rtype;
11706
11707 for (l = 0; l < n; l++) {
11708 dof_sec_t *subsec;
11709 void **bufp;
11710 uint32_t *lenp;
11711
11712 if ((subsec = dtrace_dof_sect(dof, DOF_SECT_NONE,
11713 dofd->dofd_links[l])) == NULL)
11714 goto err; /* invalid section link */
11715
11716 if (ttl + subsec->dofs_size > max) {
11717 dtrace_dof_error(dof, "exceeds maximum size");
11718 goto err;
11719 }
11720
11721 ttl += subsec->dofs_size;
11722
11723 for (i = 0; difo[i].section != DOF_SECT_NONE; i++) {
11724 if (subsec->dofs_type != difo[i].section)
11725 continue;
11726
11727 if (!(subsec->dofs_flags & DOF_SECF_LOAD)) {
11728 dtrace_dof_error(dof, "section not loaded");
11729 goto err;
11730 }
11731
11732 if (subsec->dofs_align != difo[i].align) {
11733 dtrace_dof_error(dof, "bad alignment");
11734 goto err;
11735 }
11736
11737 bufp = (void **)((uintptr_t)dp + difo[i].bufoffs);
11738 lenp = (uint32_t *)((uintptr_t)dp + difo[i].lenoffs);
11739
11740 if (*bufp != NULL) {
11741 dtrace_dof_error(dof, difo[i].msg);
11742 goto err;
11743 }
11744
11745 if (difo[i].entsize != subsec->dofs_entsize) {
11746 dtrace_dof_error(dof, "entry size mismatch");
11747 goto err;
11748 }
11749
11750 if (subsec->dofs_entsize != 0 &&
11751 (subsec->dofs_size % subsec->dofs_entsize) != 0) {
11752 dtrace_dof_error(dof, "corrupt entry size");
11753 goto err;
11754 }
11755
11756 *lenp = subsec->dofs_size;
11757 *bufp = kmem_alloc(subsec->dofs_size, KM_SLEEP);
11758 bcopy((char *)(uintptr_t)(daddr + subsec->dofs_offset),
11759 *bufp, subsec->dofs_size);
11760
11761 if (subsec->dofs_entsize != 0)
11762 *lenp /= subsec->dofs_entsize;
11763
11764 break;
11765 }
11766
11767 /*
11768 * If we encounter a loadable DIFO sub-section that is not
11769 * known to us, assume this is a broken program and fail.
11770 */
11771 if (difo[i].section == DOF_SECT_NONE &&
11772 (subsec->dofs_flags & DOF_SECF_LOAD)) {
11773 dtrace_dof_error(dof, "unrecognized DIFO subsection");
11774 goto err;
11775 }
11776 }
11777
11778 if (dp->dtdo_buf == NULL) {
11779 /*
11780 * We can't have a DIF object without DIF text.
11781 */
11782 dtrace_dof_error(dof, "missing DIF text");
11783 goto err;
11784 }
11785
11786 /*
11787 * Before we validate the DIF object, run through the variable table
11788 * looking for the strings -- if any of their size are under, we'll set
11789 * their size to be the system-wide default string size. Note that
11790 * this should _not_ happen if the "strsize" option has been set --
11791 * in this case, the compiler should have set the size to reflect the
11792 * setting of the option.
11793 */
11794 for (i = 0; i < dp->dtdo_varlen; i++) {
11795 dtrace_difv_t *v = &dp->dtdo_vartab[i];
11796 dtrace_diftype_t *t = &v->dtdv_type;
11797
11798 if (v->dtdv_id < DIF_VAR_OTHER_UBASE)
11799 continue;
11800
11801 if (t->dtdt_kind == DIF_TYPE_STRING && t->dtdt_size == 0)
11802 t->dtdt_size = dtrace_strsize_default;
11803 }
11804
11805 if (dtrace_difo_validate(dp, vstate, DIF_DIR_NREGS, cr) != 0)
11806 goto err;
11807
11808 dtrace_difo_init(dp, vstate);
11809 return (dp);
11810
11811 err:
11812 kmem_free(dp->dtdo_buf, dp->dtdo_len * sizeof (dif_instr_t));
11813 kmem_free(dp->dtdo_inttab, dp->dtdo_intlen * sizeof (uint64_t));
11814 kmem_free(dp->dtdo_strtab, dp->dtdo_strlen);
11815 kmem_free(dp->dtdo_vartab, dp->dtdo_varlen * sizeof (dtrace_difv_t));
11816
11817 kmem_free(dp, sizeof (dtrace_difo_t));
11818 return (NULL);
11819 }
11820
11821 static dtrace_predicate_t *
11822 dtrace_dof_predicate(dof_hdr_t *dof, dof_sec_t *sec, dtrace_vstate_t *vstate,
11823 cred_t *cr)
11824 {
11825 dtrace_difo_t *dp;
11826
11827 if ((dp = dtrace_dof_difo(dof, sec, vstate, cr)) == NULL)
11828 return (NULL);
11829
11830 return (dtrace_predicate_create(dp));
11831 }
11832
11833 static dtrace_actdesc_t *
11834 dtrace_dof_actdesc(dof_hdr_t *dof, dof_sec_t *sec, dtrace_vstate_t *vstate,
11835 cred_t *cr)
11836 {
11837 dtrace_actdesc_t *act, *first = NULL, *last = NULL, *next;
11838 dof_actdesc_t *desc;
11839 dof_sec_t *difosec;
11840 size_t offs;
11841 uintptr_t daddr = (uintptr_t)dof;
11842 uint64_t arg;
11843 dtrace_actkind_t kind;
11844
11845 if (sec->dofs_type != DOF_SECT_ACTDESC) {
11846 dtrace_dof_error(dof, "invalid action section");
11847 return (NULL);
11848 }
11849
11850 if (sec->dofs_offset + sizeof (dof_actdesc_t) > dof->dofh_loadsz) {
11851 dtrace_dof_error(dof, "truncated action description");
11852 return (NULL);
11853 }
11854
11855 if (sec->dofs_align != sizeof (uint64_t)) {
11856 dtrace_dof_error(dof, "bad alignment in action description");
11857 return (NULL);
11858 }
11859
11860 if (sec->dofs_size < sec->dofs_entsize) {
11861 dtrace_dof_error(dof, "section entry size exceeds total size");
11862 return (NULL);
11863 }
11864
11865 if (sec->dofs_entsize != sizeof (dof_actdesc_t)) {
11866 dtrace_dof_error(dof, "bad entry size in action description");
11867 return (NULL);
11868 }
11869
11870 if (sec->dofs_size / sec->dofs_entsize > dtrace_actions_max) {
11871 dtrace_dof_error(dof, "actions exceed dtrace_actions_max");
11872 return (NULL);
11873 }
11874
11875 for (offs = 0; offs < sec->dofs_size; offs += sec->dofs_entsize) {
11876 desc = (dof_actdesc_t *)(daddr +
11877 (uintptr_t)sec->dofs_offset + offs);
11878 kind = (dtrace_actkind_t)desc->dofa_kind;
11879
11880 if ((DTRACEACT_ISPRINTFLIKE(kind) &&
11881 (kind != DTRACEACT_PRINTA ||
11882 desc->dofa_strtab != DOF_SECIDX_NONE)) ||
11883 (kind == DTRACEACT_DIFEXPR &&
11884 desc->dofa_strtab != DOF_SECIDX_NONE)) {
11885 dof_sec_t *strtab;
11886 char *str, *fmt;
11887 uint64_t i;
11888
11889 /*
11890 * The argument to these actions is an index into the
11891 * DOF string table. For printf()-like actions, this
11892 * is the format string. For print(), this is the
11893 * CTF type of the expression result.
11894 */
11895 if ((strtab = dtrace_dof_sect(dof,
11896 DOF_SECT_STRTAB, desc->dofa_strtab)) == NULL)
11897 goto err;
11898
11899 str = (char *)((uintptr_t)dof +
11900 (uintptr_t)strtab->dofs_offset);
11901
11902 for (i = desc->dofa_arg; i < strtab->dofs_size; i++) {
11903 if (str[i] == '\0')
11904 break;
11905 }
11906
11907 if (i >= strtab->dofs_size) {
11908 dtrace_dof_error(dof, "bogus format string");
11909 goto err;
11910 }
11911
11912 if (i == desc->dofa_arg) {
11913 dtrace_dof_error(dof, "empty format string");
11914 goto err;
11915 }
11916
11917 i -= desc->dofa_arg;
11918 fmt = kmem_alloc(i + 1, KM_SLEEP);
11919 bcopy(&str[desc->dofa_arg], fmt, i + 1);
11920 arg = (uint64_t)(uintptr_t)fmt;
11921 } else {
11922 if (kind == DTRACEACT_PRINTA) {
11923 ASSERT(desc->dofa_strtab == DOF_SECIDX_NONE);
11924 arg = 0;
11925 } else {
11926 arg = desc->dofa_arg;
11927 }
11928 }
11929
11930 act = dtrace_actdesc_create(kind, desc->dofa_ntuple,
11931 desc->dofa_uarg, arg);
11932
11933 if (last != NULL) {
11934 last->dtad_next = act;
11935 } else {
11936 first = act;
11937 }
11938
11939 last = act;
11940
11941 if (desc->dofa_difo == DOF_SECIDX_NONE)
11942 continue;
11943
11944 if ((difosec = dtrace_dof_sect(dof,
11945 DOF_SECT_DIFOHDR, desc->dofa_difo)) == NULL)
11946 goto err;
11947
11948 act->dtad_difo = dtrace_dof_difo(dof, difosec, vstate, cr);
11949
11950 if (act->dtad_difo == NULL)
11951 goto err;
11952 }
11953
11954 ASSERT(first != NULL);
11955 return (first);
11956
11957 err:
11958 for (act = first; act != NULL; act = next) {
11959 next = act->dtad_next;
11960 dtrace_actdesc_release(act, vstate);
11961 }
11962
11963 return (NULL);
11964 }
11965
11966 static dtrace_ecbdesc_t *
11967 dtrace_dof_ecbdesc(dof_hdr_t *dof, dof_sec_t *sec, dtrace_vstate_t *vstate,
11968 cred_t *cr)
11969 {
11970 dtrace_ecbdesc_t *ep;
11971 dof_ecbdesc_t *ecb;
11972 dtrace_probedesc_t *desc;
11973 dtrace_predicate_t *pred = NULL;
11974
11975 if (sec->dofs_size < sizeof (dof_ecbdesc_t)) {
11976 dtrace_dof_error(dof, "truncated ECB description");
11977 return (NULL);
11978 }
11979
11980 if (sec->dofs_align != sizeof (uint64_t)) {
11981 dtrace_dof_error(dof, "bad alignment in ECB description");
11982 return (NULL);
11983 }
11984
11985 ecb = (dof_ecbdesc_t *)((uintptr_t)dof + (uintptr_t)sec->dofs_offset);
11986 sec = dtrace_dof_sect(dof, DOF_SECT_PROBEDESC, ecb->dofe_probes);
11987
11988 if (sec == NULL)
11989 return (NULL);
11990
11991 ep = kmem_zalloc(sizeof (dtrace_ecbdesc_t), KM_SLEEP);
11992 ep->dted_uarg = ecb->dofe_uarg;
11993 desc = &ep->dted_probe;
11994
11995 if (dtrace_dof_probedesc(dof, sec, desc) == NULL)
11996 goto err;
11997
11998 if (ecb->dofe_pred != DOF_SECIDX_NONE) {
11999 if ((sec = dtrace_dof_sect(dof,
12000 DOF_SECT_DIFOHDR, ecb->dofe_pred)) == NULL)
12001 goto err;
12002
12003 if ((pred = dtrace_dof_predicate(dof, sec, vstate, cr)) == NULL)
12004 goto err;
12005
12006 ep->dted_pred.dtpdd_predicate = pred;
12007 }
12008
12009 if (ecb->dofe_actions != DOF_SECIDX_NONE) {
12010 if ((sec = dtrace_dof_sect(dof,
12011 DOF_SECT_ACTDESC, ecb->dofe_actions)) == NULL)
12012 goto err;
12013
12014 ep->dted_action = dtrace_dof_actdesc(dof, sec, vstate, cr);
12015
12016 if (ep->dted_action == NULL)
12017 goto err;
12018 }
12019
12020 return (ep);
12021
12022 err:
12023 if (pred != NULL)
12024 dtrace_predicate_release(pred, vstate);
12025 kmem_free(ep, sizeof (dtrace_ecbdesc_t));
12026 return (NULL);
12027 }
12028
12029 /*
12030 * Apply the relocations from the specified 'sec' (a DOF_SECT_URELHDR) to the
12031 * specified DOF. At present, this amounts to simply adding 'ubase' to the
12032 * site of any user SETX relocations to account for load object base address.
12033 * In the future, if we need other relocations, this function can be extended.
12034 */
12035 static int
12036 dtrace_dof_relocate(dof_hdr_t *dof, dof_sec_t *sec, uint64_t ubase)
12037 {
12038 uintptr_t daddr = (uintptr_t)dof;
12039 dof_relohdr_t *dofr =
12040 (dof_relohdr_t *)(uintptr_t)(daddr + sec->dofs_offset);
12041 dof_sec_t *ss, *rs, *ts;
12042 dof_relodesc_t *r;
12043 uint_t i, n;
12044
12045 if (sec->dofs_size < sizeof (dof_relohdr_t) ||
12046 sec->dofs_align != sizeof (dof_secidx_t)) {
12047 dtrace_dof_error(dof, "invalid relocation header");
12048 return (-1);
12049 }
12050
12051 ss = dtrace_dof_sect(dof, DOF_SECT_STRTAB, dofr->dofr_strtab);
12052 rs = dtrace_dof_sect(dof, DOF_SECT_RELTAB, dofr->dofr_relsec);
12053 ts = dtrace_dof_sect(dof, DOF_SECT_NONE, dofr->dofr_tgtsec);
12054
12055 if (ss == NULL || rs == NULL || ts == NULL)
12056 return (-1); /* dtrace_dof_error() has been called already */
12057
12058 if (rs->dofs_entsize < sizeof (dof_relodesc_t) ||
12059 rs->dofs_align != sizeof (uint64_t)) {
12060 dtrace_dof_error(dof, "invalid relocation section");
12061 return (-1);
12062 }
12063
12064 r = (dof_relodesc_t *)(uintptr_t)(daddr + rs->dofs_offset);
12065 n = rs->dofs_size / rs->dofs_entsize;
12066
12067 for (i = 0; i < n; i++) {
12068 uintptr_t taddr = daddr + ts->dofs_offset + r->dofr_offset;
12069
12070 switch (r->dofr_type) {
12071 case DOF_RELO_NONE:
12072 break;
12073 case DOF_RELO_SETX:
12074 if (r->dofr_offset >= ts->dofs_size || r->dofr_offset +
12075 sizeof (uint64_t) > ts->dofs_size) {
12076 dtrace_dof_error(dof, "bad relocation offset");
12077 return (-1);
12078 }
12079
12080 if (!IS_P2ALIGNED(taddr, sizeof (uint64_t))) {
12081 dtrace_dof_error(dof, "misaligned setx relo");
12082 return (-1);
12083 }
12084
12085 *(uint64_t *)taddr += ubase;
12086 break;
12087 default:
12088 dtrace_dof_error(dof, "invalid relocation type");
12089 return (-1);
12090 }
12091
12092 r = (dof_relodesc_t *)((uintptr_t)r + rs->dofs_entsize);
12093 }
12094
12095 return (0);
12096 }
12097
12098 /*
12099 * The dof_hdr_t passed to dtrace_dof_slurp() should be a partially validated
12100 * header: it should be at the front of a memory region that is at least
12101 * sizeof (dof_hdr_t) in size -- and then at least dof_hdr.dofh_loadsz in
12102 * size. It need not be validated in any other way.
12103 */
12104 static int
12105 dtrace_dof_slurp(dof_hdr_t *dof, dtrace_vstate_t *vstate, cred_t *cr,
12106 dtrace_enabling_t **enabp, uint64_t ubase, int noprobes)
12107 {
12108 uint64_t len = dof->dofh_loadsz, seclen;
12109 uintptr_t daddr = (uintptr_t)dof;
12110 dtrace_ecbdesc_t *ep;
12111 dtrace_enabling_t *enab;
12112 uint_t i;
12113
12114 ASSERT(MUTEX_HELD(&dtrace_lock));
12115 ASSERT(dof->dofh_loadsz >= sizeof (dof_hdr_t));
12116
12117 /*
12118 * Check the DOF header identification bytes. In addition to checking
12119 * valid settings, we also verify that unused bits/bytes are zeroed so
12120 * we can use them later without fear of regressing existing binaries.
12121 */
12122 if (bcmp(&dof->dofh_ident[DOF_ID_MAG0],
12123 DOF_MAG_STRING, DOF_MAG_STRLEN) != 0) {
12124 dtrace_dof_error(dof, "DOF magic string mismatch");
12125 return (-1);
12126 }
12127
12128 if (dof->dofh_ident[DOF_ID_MODEL] != DOF_MODEL_ILP32 &&
12129 dof->dofh_ident[DOF_ID_MODEL] != DOF_MODEL_LP64) {
12130 dtrace_dof_error(dof, "DOF has invalid data model");
12131 return (-1);
12132 }
12133
12134 if (dof->dofh_ident[DOF_ID_ENCODING] != DOF_ENCODE_NATIVE) {
12135 dtrace_dof_error(dof, "DOF encoding mismatch");
12136 return (-1);
12137 }
12138
12139 if (dof->dofh_ident[DOF_ID_VERSION] != DOF_VERSION_1 &&
12140 dof->dofh_ident[DOF_ID_VERSION] != DOF_VERSION_2) {
12141 dtrace_dof_error(dof, "DOF version mismatch");
12142 return (-1);
12143 }
12144
12145 if (dof->dofh_ident[DOF_ID_DIFVERS] != DIF_VERSION_2) {
12146 dtrace_dof_error(dof, "DOF uses unsupported instruction set");
12147 return (-1);
12148 }
12149
12150 if (dof->dofh_ident[DOF_ID_DIFIREG] > DIF_DIR_NREGS) {
12151 dtrace_dof_error(dof, "DOF uses too many integer registers");
12152 return (-1);
12153 }
12154
12155 if (dof->dofh_ident[DOF_ID_DIFTREG] > DIF_DTR_NREGS) {
12156 dtrace_dof_error(dof, "DOF uses too many tuple registers");
12157 return (-1);
12158 }
12159
12160 for (i = DOF_ID_PAD; i < DOF_ID_SIZE; i++) {
12161 if (dof->dofh_ident[i] != 0) {
12162 dtrace_dof_error(dof, "DOF has invalid ident byte set");
12163 return (-1);
12164 }
12165 }
12166
12167 if (dof->dofh_flags & ~DOF_FL_VALID) {
12168 dtrace_dof_error(dof, "DOF has invalid flag bits set");
12169 return (-1);
12170 }
12171
12172 if (dof->dofh_secsize == 0) {
12173 dtrace_dof_error(dof, "zero section header size");
12174 return (-1);
12175 }
12176
12177 /*
12178 * Check that the section headers don't exceed the amount of DOF
12179 * data. Note that we cast the section size and number of sections
12180 * to uint64_t's to prevent possible overflow in the multiplication.
12181 */
12182 seclen = (uint64_t)dof->dofh_secnum * (uint64_t)dof->dofh_secsize;
12183
12184 if (dof->dofh_secoff > len || seclen > len ||
12185 dof->dofh_secoff + seclen > len) {
12186 dtrace_dof_error(dof, "truncated section headers");
12187 return (-1);
12188 }
12189
12190 if (!IS_P2ALIGNED(dof->dofh_secoff, sizeof (uint64_t))) {
12191 dtrace_dof_error(dof, "misaligned section headers");
12192 return (-1);
12193 }
12194
12195 if (!IS_P2ALIGNED(dof->dofh_secsize, sizeof (uint64_t))) {
12196 dtrace_dof_error(dof, "misaligned section size");
12197 return (-1);
12198 }
12199
12200 /*
12201 * Take an initial pass through the section headers to be sure that
12202 * the headers don't have stray offsets. If the 'noprobes' flag is
12203 * set, do not permit sections relating to providers, probes, or args.
12204 */
12205 for (i = 0; i < dof->dofh_secnum; i++) {
12206 dof_sec_t *sec = (dof_sec_t *)(daddr +
12207 (uintptr_t)dof->dofh_secoff + i * dof->dofh_secsize);
12208
12209 if (noprobes) {
12210 switch (sec->dofs_type) {
12211 case DOF_SECT_PROVIDER:
12212 case DOF_SECT_PROBES:
12213 case DOF_SECT_PRARGS:
12214 case DOF_SECT_PROFFS:
12215 dtrace_dof_error(dof, "illegal sections "
12216 "for enabling");
12217 return (-1);
12218 }
12219 }
12220
12221 if (DOF_SEC_ISLOADABLE(sec->dofs_type) &&
12222 !(sec->dofs_flags & DOF_SECF_LOAD)) {
12223 dtrace_dof_error(dof, "loadable section with load "
12224 "flag unset");
12225 return (-1);
12226 }
12227
12228 if (!(sec->dofs_flags & DOF_SECF_LOAD))
12229 continue; /* just ignore non-loadable sections */
12230
12231 if (sec->dofs_align & (sec->dofs_align - 1)) {
12232 dtrace_dof_error(dof, "bad section alignment");
12233 return (-1);
12234 }
12235
12236 if (sec->dofs_offset & (sec->dofs_align - 1)) {
12237 dtrace_dof_error(dof, "misaligned section");
12238 return (-1);
12239 }
12240
12241 if (sec->dofs_offset > len || sec->dofs_size > len ||
12242 sec->dofs_offset + sec->dofs_size > len) {
12243 dtrace_dof_error(dof, "corrupt section header");
12244 return (-1);
12245 }
12246
12247 if (sec->dofs_type == DOF_SECT_STRTAB && *((char *)daddr +
12248 sec->dofs_offset + sec->dofs_size - 1) != '\0') {
12249 dtrace_dof_error(dof, "non-terminating string table");
12250 return (-1);
12251 }
12252 }
12253
12254 /*
12255 * Take a second pass through the sections and locate and perform any
12256 * relocations that are present. We do this after the first pass to
12257 * be sure that all sections have had their headers validated.
12258 */
12259 for (i = 0; i < dof->dofh_secnum; i++) {
12260 dof_sec_t *sec = (dof_sec_t *)(daddr +
12261 (uintptr_t)dof->dofh_secoff + i * dof->dofh_secsize);
12262
12263 if (!(sec->dofs_flags & DOF_SECF_LOAD))
12264 continue; /* skip sections that are not loadable */
12265
12266 switch (sec->dofs_type) {
12267 case DOF_SECT_URELHDR:
12268 if (dtrace_dof_relocate(dof, sec, ubase) != 0)
12269 return (-1);
12270 break;
12271 }
12272 }
12273
12274 if ((enab = *enabp) == NULL)
12275 enab = *enabp = dtrace_enabling_create(vstate);
12276
12277 for (i = 0; i < dof->dofh_secnum; i++) {
12278 dof_sec_t *sec = (dof_sec_t *)(daddr +
12279 (uintptr_t)dof->dofh_secoff + i * dof->dofh_secsize);
12280
12281 if (sec->dofs_type != DOF_SECT_ECBDESC)
12282 continue;
12283
12284 if ((ep = dtrace_dof_ecbdesc(dof, sec, vstate, cr)) == NULL) {
12285 dtrace_enabling_destroy(enab);
12286 *enabp = NULL;
12287 return (-1);
12288 }
12289
12290 dtrace_enabling_add(enab, ep);
12291 }
12292
12293 return (0);
12294 }
12295
12296 /*
12297 * Process DOF for any options. This routine assumes that the DOF has been
12298 * at least processed by dtrace_dof_slurp().
12299 */
12300 static int
12301 dtrace_dof_options(dof_hdr_t *dof, dtrace_state_t *state)
12302 {
12303 int i, rval;
12304 uint32_t entsize;
12305 size_t offs;
12306 dof_optdesc_t *desc;
12307
12308 for (i = 0; i < dof->dofh_secnum; i++) {
12309 dof_sec_t *sec = (dof_sec_t *)((uintptr_t)dof +
12310 (uintptr_t)dof->dofh_secoff + i * dof->dofh_secsize);
12311
12312 if (sec->dofs_type != DOF_SECT_OPTDESC)
12313 continue;
12314
12315 if (sec->dofs_align != sizeof (uint64_t)) {
12316 dtrace_dof_error(dof, "bad alignment in "
12317 "option description");
12318 return (EINVAL);
12319 }
12320
12321 if ((entsize = sec->dofs_entsize) == 0) {
12322 dtrace_dof_error(dof, "zeroed option entry size");
12323 return (EINVAL);
12324 }
12325
12326 if (entsize < sizeof (dof_optdesc_t)) {
12327 dtrace_dof_error(dof, "bad option entry size");
12328 return (EINVAL);
12329 }
12330
12331 for (offs = 0; offs < sec->dofs_size; offs += entsize) {
12332 desc = (dof_optdesc_t *)((uintptr_t)dof +
12333 (uintptr_t)sec->dofs_offset + offs);
12334
12335 if (desc->dofo_strtab != DOF_SECIDX_NONE) {
12336 dtrace_dof_error(dof, "non-zero option string");
12337 return (EINVAL);
12338 }
12339
12340 if (desc->dofo_value == DTRACEOPT_UNSET) {
12341 dtrace_dof_error(dof, "unset option");
12342 return (EINVAL);
12343 }
12344
12345 if ((rval = dtrace_state_option(state,
12346 desc->dofo_option, desc->dofo_value)) != 0) {
12347 dtrace_dof_error(dof, "rejected option");
12348 return (rval);
12349 }
12350 }
12351 }
12352
12353 return (0);
12354 }
12355
12356 /*
12357 * DTrace Consumer State Functions
12358 */
12359 int
12360 dtrace_dstate_init(dtrace_dstate_t *dstate, size_t size)
12361 {
12362 size_t hashsize, maxper, min, chunksize = dstate->dtds_chunksize;
12363 void *base;
12364 uintptr_t limit;
12365 dtrace_dynvar_t *dvar, *next, *start;
12366 int i;
12367
12368 ASSERT(MUTEX_HELD(&dtrace_lock));
12369 ASSERT(dstate->dtds_base == NULL && dstate->dtds_percpu == NULL);
12370
12371 bzero(dstate, sizeof (dtrace_dstate_t));
12372
12373 if ((dstate->dtds_chunksize = chunksize) == 0)
12374 dstate->dtds_chunksize = DTRACE_DYNVAR_CHUNKSIZE;
12375
12376 if (size < (min = dstate->dtds_chunksize + sizeof (dtrace_dynhash_t)))
12377 size = min;
12378
12379 if ((base = kmem_zalloc(size, KM_NOSLEEP | KM_NORMALPRI)) == NULL)
12380 return (ENOMEM);
12381
12382 dstate->dtds_size = size;
12383 dstate->dtds_base = base;
12384 dstate->dtds_percpu = kmem_cache_alloc(dtrace_state_cache, KM_SLEEP);
12385 bzero(dstate->dtds_percpu, NCPU * sizeof (dtrace_dstate_percpu_t));
12386
12387 hashsize = size / (dstate->dtds_chunksize + sizeof (dtrace_dynhash_t));
12388
12389 if (hashsize != 1 && (hashsize & 1))
12390 hashsize--;
12391
12392 dstate->dtds_hashsize = hashsize;
12393 dstate->dtds_hash = dstate->dtds_base;
12394
12395 /*
12396 * Set all of our hash buckets to point to the single sink, and (if
12397 * it hasn't already been set), set the sink's hash value to be the
12398 * sink sentinel value. The sink is needed for dynamic variable
12399 * lookups to know that they have iterated over an entire, valid hash
12400 * chain.
12401 */
12402 for (i = 0; i < hashsize; i++)
12403 dstate->dtds_hash[i].dtdh_chain = &dtrace_dynhash_sink;
12404
12405 if (dtrace_dynhash_sink.dtdv_hashval != DTRACE_DYNHASH_SINK)
12406 dtrace_dynhash_sink.dtdv_hashval = DTRACE_DYNHASH_SINK;
12407
12408 /*
12409 * Determine number of active CPUs. Divide free list evenly among
12410 * active CPUs.
12411 */
12412 start = (dtrace_dynvar_t *)
12413 ((uintptr_t)base + hashsize * sizeof (dtrace_dynhash_t));
12414 limit = (uintptr_t)base + size;
12415
12416 maxper = (limit - (uintptr_t)start) / NCPU;
12417 maxper = (maxper / dstate->dtds_chunksize) * dstate->dtds_chunksize;
12418
12419 for (i = 0; i < NCPU; i++) {
12420 dstate->dtds_percpu[i].dtdsc_free = dvar = start;
12421
12422 /*
12423 * If we don't even have enough chunks to make it once through
12424 * NCPUs, we're just going to allocate everything to the first
12425 * CPU. And if we're on the last CPU, we're going to allocate
12426 * whatever is left over. In either case, we set the limit to
12427 * be the limit of the dynamic variable space.
12428 */
12429 if (maxper == 0 || i == NCPU - 1) {
12430 limit = (uintptr_t)base + size;
12431 start = NULL;
12432 } else {
12433 limit = (uintptr_t)start + maxper;
12434 start = (dtrace_dynvar_t *)limit;
12435 }
12436
12437 ASSERT(limit <= (uintptr_t)base + size);
12438
12439 for (;;) {
12440 next = (dtrace_dynvar_t *)((uintptr_t)dvar +
12441 dstate->dtds_chunksize);
12442
12443 if ((uintptr_t)next + dstate->dtds_chunksize >= limit)
12444 break;
12445
12446 dvar->dtdv_next = next;
12447 dvar = next;
12448 }
12449
12450 if (maxper == 0)
12451 break;
12452 }
12453
12454 return (0);
12455 }
12456
12457 void
12458 dtrace_dstate_fini(dtrace_dstate_t *dstate)
12459 {
12460 ASSERT(MUTEX_HELD(&cpu_lock));
12461
12462 if (dstate->dtds_base == NULL)
12463 return;
12464
12465 kmem_free(dstate->dtds_base, dstate->dtds_size);
12466 kmem_cache_free(dtrace_state_cache, dstate->dtds_percpu);
12467 }
12468
12469 static void
12470 dtrace_vstate_fini(dtrace_vstate_t *vstate)
12471 {
12472 /*
12473 * Logical XOR, where are you?
12474 */
12475 ASSERT((vstate->dtvs_nglobals == 0) ^ (vstate->dtvs_globals != NULL));
12476
12477 if (vstate->dtvs_nglobals > 0) {
12478 kmem_free(vstate->dtvs_globals, vstate->dtvs_nglobals *
12479 sizeof (dtrace_statvar_t *));
12480 }
12481
12482 if (vstate->dtvs_ntlocals > 0) {
12483 kmem_free(vstate->dtvs_tlocals, vstate->dtvs_ntlocals *
12484 sizeof (dtrace_difv_t));
12485 }
12486
12487 ASSERT((vstate->dtvs_nlocals == 0) ^ (vstate->dtvs_locals != NULL));
12488
12489 if (vstate->dtvs_nlocals > 0) {
12490 kmem_free(vstate->dtvs_locals, vstate->dtvs_nlocals *
12491 sizeof (dtrace_statvar_t *));
12492 }
12493 }
12494
12495 static void
12496 dtrace_state_clean(dtrace_state_t *state)
12497 {
12498 if (state->dts_activity == DTRACE_ACTIVITY_INACTIVE)
12499 return;
12500
12501 dtrace_dynvar_clean(&state->dts_vstate.dtvs_dynvars);
12502 dtrace_speculation_clean(state);
12503 }
12504
12505 static void
12506 dtrace_state_deadman(dtrace_state_t *state)
12507 {
12508 hrtime_t now;
12509
12510 dtrace_sync();
12511
12512 now = dtrace_gethrtime();
12513
12514 if (state != dtrace_anon.dta_state &&
12515 now - state->dts_laststatus >= dtrace_deadman_user)
12516 return;
12517
12518 /*
12519 * We must be sure that dts_alive never appears to be less than the
12520 * value upon entry to dtrace_state_deadman(), and because we lack a
12521 * dtrace_cas64(), we cannot store to it atomically. We thus instead
12522 * store INT64_MAX to it, followed by a memory barrier, followed by
12523 * the new value. This assures that dts_alive never appears to be
12524 * less than its true value, regardless of the order in which the
12525 * stores to the underlying storage are issued.
12526 */
12527 state->dts_alive = INT64_MAX;
12528 dtrace_membar_producer();
12529 state->dts_alive = now;
12530 }
12531
12532 dtrace_state_t *
12533 dtrace_state_create(dev_t *devp, cred_t *cr)
12534 {
12535 minor_t minor;
12536 major_t major;
12537 char c[30];
12538 dtrace_state_t *state;
12539 dtrace_optval_t *opt;
12540 int bufsize = NCPU * sizeof (dtrace_buffer_t), i;
12541
12542 ASSERT(MUTEX_HELD(&dtrace_lock));
12543 ASSERT(MUTEX_HELD(&cpu_lock));
12544
12545 minor = (minor_t)(uintptr_t)vmem_alloc(dtrace_minor, 1,
12546 VM_BESTFIT | VM_SLEEP);
12547
12548 if (ddi_soft_state_zalloc(dtrace_softstate, minor) != DDI_SUCCESS) {
12549 vmem_free(dtrace_minor, (void *)(uintptr_t)minor, 1);
12550 return (NULL);
12551 }
12552
12553 state = ddi_get_soft_state(dtrace_softstate, minor);
12554 state->dts_epid = DTRACE_EPIDNONE + 1;
12555
12556 (void) snprintf(c, sizeof (c), "dtrace_aggid_%d", minor);
12557 state->dts_aggid_arena = vmem_create(c, (void *)1, UINT32_MAX, 1,
12558 NULL, NULL, NULL, 0, VM_SLEEP | VMC_IDENTIFIER);
12559
12560 if (devp != NULL) {
12561 major = getemajor(*devp);
12562 } else {
12563 major = ddi_driver_major(dtrace_devi);
12564 }
12565
12566 state->dts_dev = makedevice(major, minor);
12567
12568 if (devp != NULL)
12569 *devp = state->dts_dev;
12570
12571 /*
12572 * We allocate NCPU buffers. On the one hand, this can be quite
12573 * a bit of memory per instance (nearly 36K on a Starcat). On the
12574 * other hand, it saves an additional memory reference in the probe
12575 * path.
12576 */
12577 state->dts_buffer = kmem_zalloc(bufsize, KM_SLEEP);
12578 state->dts_aggbuffer = kmem_zalloc(bufsize, KM_SLEEP);
12579 state->dts_cleaner = CYCLIC_NONE;
12580 state->dts_deadman = CYCLIC_NONE;
12581 state->dts_vstate.dtvs_state = state;
12582
12583 for (i = 0; i < DTRACEOPT_MAX; i++)
12584 state->dts_options[i] = DTRACEOPT_UNSET;
12585
12586 /*
12587 * Set the default options.
12588 */
12589 opt = state->dts_options;
12590 opt[DTRACEOPT_BUFPOLICY] = DTRACEOPT_BUFPOLICY_SWITCH;
12591 opt[DTRACEOPT_BUFRESIZE] = DTRACEOPT_BUFRESIZE_AUTO;
12592 opt[DTRACEOPT_NSPEC] = dtrace_nspec_default;
12593 opt[DTRACEOPT_SPECSIZE] = dtrace_specsize_default;
12594 opt[DTRACEOPT_CPU] = (dtrace_optval_t)DTRACE_CPUALL;
12595 opt[DTRACEOPT_STRSIZE] = dtrace_strsize_default;
12596 opt[DTRACEOPT_STACKFRAMES] = dtrace_stackframes_default;
12597 opt[DTRACEOPT_USTACKFRAMES] = dtrace_ustackframes_default;
12598 opt[DTRACEOPT_CLEANRATE] = dtrace_cleanrate_default;
12599 opt[DTRACEOPT_AGGRATE] = dtrace_aggrate_default;
12600 opt[DTRACEOPT_SWITCHRATE] = dtrace_switchrate_default;
12601 opt[DTRACEOPT_STATUSRATE] = dtrace_statusrate_default;
12602 opt[DTRACEOPT_JSTACKFRAMES] = dtrace_jstackframes_default;
12603 opt[DTRACEOPT_JSTACKSTRSIZE] = dtrace_jstackstrsize_default;
12604
12605 state->dts_activity = DTRACE_ACTIVITY_INACTIVE;
12606
12607 /*
12608 * Depending on the user credentials, we set flag bits which alter probe
12609 * visibility or the amount of destructiveness allowed. In the case of
12610 * actual anonymous tracing, or the possession of all privileges, all of
12611 * the normal checks are bypassed.
12612 */
12613 if (cr == NULL || PRIV_POLICY_ONLY(cr, PRIV_ALL, B_FALSE)) {
12614 state->dts_cred.dcr_visible = DTRACE_CRV_ALL;
12615 state->dts_cred.dcr_action = DTRACE_CRA_ALL;
12616 } else {
12617 /*
12618 * Set up the credentials for this instantiation. We take a
12619 * hold on the credential to prevent it from disappearing on
12620 * us; this in turn prevents the zone_t referenced by this
12621 * credential from disappearing. This means that we can
12622 * examine the credential and the zone from probe context.
12623 */
12624 crhold(cr);
12625 state->dts_cred.dcr_cred = cr;
12626
12627 /*
12628 * CRA_PROC means "we have *some* privilege for dtrace" and
12629 * unlocks the use of variables like pid, zonename, etc.
12630 */
12631 if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_USER, B_FALSE) ||
12632 PRIV_POLICY_ONLY(cr, PRIV_DTRACE_PROC, B_FALSE)) {
12633 state->dts_cred.dcr_action |= DTRACE_CRA_PROC;
12634 }
12635
12636 /*
12637 * dtrace_user allows use of syscall and profile providers.
12638 * If the user also has proc_owner and/or proc_zone, we
12639 * extend the scope to include additional visibility and
12640 * destructive power.
12641 */
12642 if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_USER, B_FALSE)) {
12643 if (PRIV_POLICY_ONLY(cr, PRIV_PROC_OWNER, B_FALSE)) {
12644 state->dts_cred.dcr_visible |=
12645 DTRACE_CRV_ALLPROC;
12646
12647 state->dts_cred.dcr_action |=
12648 DTRACE_CRA_PROC_DESTRUCTIVE_ALLUSER;
12649 }
12650
12651 if (PRIV_POLICY_ONLY(cr, PRIV_PROC_ZONE, B_FALSE)) {
12652 state->dts_cred.dcr_visible |=
12653 DTRACE_CRV_ALLZONE;
12654
12655 state->dts_cred.dcr_action |=
12656 DTRACE_CRA_PROC_DESTRUCTIVE_ALLZONE;
12657 }
12658
12659 /*
12660 * If we have all privs in whatever zone this is,
12661 * we can do destructive things to processes which
12662 * have altered credentials.
12663 */
12664 if (priv_isequalset(priv_getset(cr, PRIV_EFFECTIVE),
12665 cr->cr_zone->zone_privset)) {
12666 state->dts_cred.dcr_action |=
12667 DTRACE_CRA_PROC_DESTRUCTIVE_CREDCHG;
12668 }
12669 }
12670
12671 /*
12672 * Holding the dtrace_kernel privilege also implies that
12673 * the user has the dtrace_user privilege from a visibility
12674 * perspective. But without further privileges, some
12675 * destructive actions are not available.
12676 */
12677 if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_KERNEL, B_FALSE)) {
12678 /*
12679 * Make all probes in all zones visible. However,
12680 * this doesn't mean that all actions become available
12681 * to all zones.
12682 */
12683 state->dts_cred.dcr_visible |= DTRACE_CRV_KERNEL |
12684 DTRACE_CRV_ALLPROC | DTRACE_CRV_ALLZONE;
12685
12686 state->dts_cred.dcr_action |= DTRACE_CRA_KERNEL |
12687 DTRACE_CRA_PROC;
12688 /*
12689 * Holding proc_owner means that destructive actions
12690 * for *this* zone are allowed.
12691 */
12692 if (PRIV_POLICY_ONLY(cr, PRIV_PROC_OWNER, B_FALSE))
12693 state->dts_cred.dcr_action |=
12694 DTRACE_CRA_PROC_DESTRUCTIVE_ALLUSER;
12695
12696 /*
12697 * Holding proc_zone means that destructive actions
12698 * for this user/group ID in all zones is allowed.
12699 */
12700 if (PRIV_POLICY_ONLY(cr, PRIV_PROC_ZONE, B_FALSE))
12701 state->dts_cred.dcr_action |=
12702 DTRACE_CRA_PROC_DESTRUCTIVE_ALLZONE;
12703
12704 /*
12705 * If we have all privs in whatever zone this is,
12706 * we can do destructive things to processes which
12707 * have altered credentials.
12708 */
12709 if (priv_isequalset(priv_getset(cr, PRIV_EFFECTIVE),
12710 cr->cr_zone->zone_privset)) {
12711 state->dts_cred.dcr_action |=
12712 DTRACE_CRA_PROC_DESTRUCTIVE_CREDCHG;
12713 }
12714 }
12715
12716 /*
12717 * Holding the dtrace_proc privilege gives control over fasttrap
12718 * and pid providers. We need to grant wider destructive
12719 * privileges in the event that the user has proc_owner and/or
12720 * proc_zone.
12721 */
12722 if (PRIV_POLICY_ONLY(cr, PRIV_DTRACE_PROC, B_FALSE)) {
12723 if (PRIV_POLICY_ONLY(cr, PRIV_PROC_OWNER, B_FALSE))
12724 state->dts_cred.dcr_action |=
12725 DTRACE_CRA_PROC_DESTRUCTIVE_ALLUSER;
12726
12727 if (PRIV_POLICY_ONLY(cr, PRIV_PROC_ZONE, B_FALSE))
12728 state->dts_cred.dcr_action |=
12729 DTRACE_CRA_PROC_DESTRUCTIVE_ALLZONE;
12730 }
12731 }
12732
12733 return (state);
12734 }
12735
12736 static int
12737 dtrace_state_buffer(dtrace_state_t *state, dtrace_buffer_t *buf, int which)
12738 {
12739 dtrace_optval_t *opt = state->dts_options, size;
12740 processorid_t cpu;
12741 int flags = 0, rval, factor, divisor = 1;
12742
12743 ASSERT(MUTEX_HELD(&dtrace_lock));
12744 ASSERT(MUTEX_HELD(&cpu_lock));
12745 ASSERT(which < DTRACEOPT_MAX);
12746 ASSERT(state->dts_activity == DTRACE_ACTIVITY_INACTIVE ||
12747 (state == dtrace_anon.dta_state &&
12748 state->dts_activity == DTRACE_ACTIVITY_ACTIVE));
12749
12750 if (opt[which] == DTRACEOPT_UNSET || opt[which] == 0)
12751 return (0);
12752
12753 if (opt[DTRACEOPT_CPU] != DTRACEOPT_UNSET)
12754 cpu = opt[DTRACEOPT_CPU];
12755
12756 if (which == DTRACEOPT_SPECSIZE)
12757 flags |= DTRACEBUF_NOSWITCH;
12758
12759 if (which == DTRACEOPT_BUFSIZE) {
12760 if (opt[DTRACEOPT_BUFPOLICY] == DTRACEOPT_BUFPOLICY_RING)
12761 flags |= DTRACEBUF_RING;
12762
12763 if (opt[DTRACEOPT_BUFPOLICY] == DTRACEOPT_BUFPOLICY_FILL)
12764 flags |= DTRACEBUF_FILL;
12765
12766 if (state != dtrace_anon.dta_state ||
12767 state->dts_activity != DTRACE_ACTIVITY_ACTIVE)
12768 flags |= DTRACEBUF_INACTIVE;
12769 }
12770
12771 for (size = opt[which]; size >= sizeof (uint64_t); size /= divisor) {
12772 /*
12773 * The size must be 8-byte aligned. If the size is not 8-byte
12774 * aligned, drop it down by the difference.
12775 */
12776 if (size & (sizeof (uint64_t) - 1))
12777 size -= size & (sizeof (uint64_t) - 1);
12778
12779 if (size < state->dts_reserve) {
12780 /*
12781 * Buffers always must be large enough to accommodate
12782 * their prereserved space. We return E2BIG instead
12783 * of ENOMEM in this case to allow for user-level
12784 * software to differentiate the cases.
12785 */
12786 return (E2BIG);
12787 }
12788
12789 rval = dtrace_buffer_alloc(buf, size, flags, cpu, &factor);
12790
12791 if (rval != ENOMEM) {
12792 opt[which] = size;
12793 return (rval);
12794 }
12795
12796 if (opt[DTRACEOPT_BUFRESIZE] == DTRACEOPT_BUFRESIZE_MANUAL)
12797 return (rval);
12798
12799 for (divisor = 2; divisor < factor; divisor <<= 1)
12800 continue;
12801 }
12802
12803 return (ENOMEM);
12804 }
12805
12806 static int
12807 dtrace_state_buffers(dtrace_state_t *state)
12808 {
12809 dtrace_speculation_t *spec = state->dts_speculations;
12810 int rval, i;
12811
12812 if ((rval = dtrace_state_buffer(state, state->dts_buffer,
12813 DTRACEOPT_BUFSIZE)) != 0)
12814 return (rval);
12815
12816 if ((rval = dtrace_state_buffer(state, state->dts_aggbuffer,
12817 DTRACEOPT_AGGSIZE)) != 0)
12818 return (rval);
12819
12820 for (i = 0; i < state->dts_nspeculations; i++) {
12821 if ((rval = dtrace_state_buffer(state,
12822 spec[i].dtsp_buffer, DTRACEOPT_SPECSIZE)) != 0)
12823 return (rval);
12824 }
12825
12826 return (0);
12827 }
12828
12829 static void
12830 dtrace_state_prereserve(dtrace_state_t *state)
12831 {
12832 dtrace_ecb_t *ecb;
12833 dtrace_probe_t *probe;
12834
12835 state->dts_reserve = 0;
12836
12837 if (state->dts_options[DTRACEOPT_BUFPOLICY] != DTRACEOPT_BUFPOLICY_FILL)
12838 return;
12839
12840 /*
12841 * If our buffer policy is a "fill" buffer policy, we need to set the
12842 * prereserved space to be the space required by the END probes.
12843 */
12844 probe = dtrace_probes[dtrace_probeid_end - 1];
12845 ASSERT(probe != NULL);
12846
12847 for (ecb = probe->dtpr_ecb; ecb != NULL; ecb = ecb->dte_next) {
12848 if (ecb->dte_state != state)
12849 continue;
12850
12851 state->dts_reserve += ecb->dte_needed + ecb->dte_alignment;
12852 }
12853 }
12854
12855 static int
12856 dtrace_state_go(dtrace_state_t *state, processorid_t *cpu)
12857 {
12858 dtrace_optval_t *opt = state->dts_options, sz, nspec;
12859 dtrace_speculation_t *spec;
12860 dtrace_buffer_t *buf;
12861 cyc_handler_t hdlr;
12862 cyc_time_t when;
12863 int rval = 0, i, bufsize = NCPU * sizeof (dtrace_buffer_t);
12864 dtrace_icookie_t cookie;
12865
12866 mutex_enter(&cpu_lock);
12867 mutex_enter(&dtrace_lock);
12868
12869 if (state->dts_activity != DTRACE_ACTIVITY_INACTIVE) {
12870 rval = EBUSY;
12871 goto out;
12872 }
12873
12874 /*
12875 * Before we can perform any checks, we must prime all of the
12876 * retained enablings that correspond to this state.
12877 */
12878 dtrace_enabling_prime(state);
12879
12880 if (state->dts_destructive && !state->dts_cred.dcr_destructive) {
12881 rval = EACCES;
12882 goto out;
12883 }
12884
12885 dtrace_state_prereserve(state);
12886
12887 /*
12888 * Now we want to do is try to allocate our speculations.
12889 * We do not automatically resize the number of speculations; if
12890 * this fails, we will fail the operation.
12891 */
12892 nspec = opt[DTRACEOPT_NSPEC];
12893 ASSERT(nspec != DTRACEOPT_UNSET);
12894
12895 if (nspec > INT_MAX) {
12896 rval = ENOMEM;
12897 goto out;
12898 }
12899
12900 spec = kmem_zalloc(nspec * sizeof (dtrace_speculation_t),
12901 KM_NOSLEEP | KM_NORMALPRI);
12902
12903 if (spec == NULL) {
12904 rval = ENOMEM;
12905 goto out;
12906 }
12907
12908 state->dts_speculations = spec;
12909 state->dts_nspeculations = (int)nspec;
12910
12911 for (i = 0; i < nspec; i++) {
12912 if ((buf = kmem_zalloc(bufsize,
12913 KM_NOSLEEP | KM_NORMALPRI)) == NULL) {
12914 rval = ENOMEM;
12915 goto err;
12916 }
12917
12918 spec[i].dtsp_buffer = buf;
12919 }
12920
12921 if (opt[DTRACEOPT_GRABANON] != DTRACEOPT_UNSET) {
12922 if (dtrace_anon.dta_state == NULL) {
12923 rval = ENOENT;
12924 goto out;
12925 }
12926
12927 if (state->dts_necbs != 0) {
12928 rval = EALREADY;
12929 goto out;
12930 }
12931
12932 state->dts_anon = dtrace_anon_grab();
12933 ASSERT(state->dts_anon != NULL);
12934 state = state->dts_anon;
12935
12936 /*
12937 * We want "grabanon" to be set in the grabbed state, so we'll
12938 * copy that option value from the grabbing state into the
12939 * grabbed state.
12940 */
12941 state->dts_options[DTRACEOPT_GRABANON] =
12942 opt[DTRACEOPT_GRABANON];
12943
12944 *cpu = dtrace_anon.dta_beganon;
12945
12946 /*
12947 * If the anonymous state is active (as it almost certainly
12948 * is if the anonymous enabling ultimately matched anything),
12949 * we don't allow any further option processing -- but we
12950 * don't return failure.
12951 */
12952 if (state->dts_activity != DTRACE_ACTIVITY_INACTIVE)
12953 goto out;
12954 }
12955
12956 if (opt[DTRACEOPT_AGGSIZE] != DTRACEOPT_UNSET &&
12957 opt[DTRACEOPT_AGGSIZE] != 0) {
12958 if (state->dts_aggregations == NULL) {
12959 /*
12960 * We're not going to create an aggregation buffer
12961 * because we don't have any ECBs that contain
12962 * aggregations -- set this option to 0.
12963 */
12964 opt[DTRACEOPT_AGGSIZE] = 0;
12965 } else {
12966 /*
12967 * If we have an aggregation buffer, we must also have
12968 * a buffer to use as scratch.
12969 */
12970 if (opt[DTRACEOPT_BUFSIZE] == DTRACEOPT_UNSET ||
12971 opt[DTRACEOPT_BUFSIZE] < state->dts_needed) {
12972 opt[DTRACEOPT_BUFSIZE] = state->dts_needed;
12973 }
12974 }
12975 }
12976
12977 if (opt[DTRACEOPT_SPECSIZE] != DTRACEOPT_UNSET &&
12978 opt[DTRACEOPT_SPECSIZE] != 0) {
12979 if (!state->dts_speculates) {
12980 /*
12981 * We're not going to create speculation buffers
12982 * because we don't have any ECBs that actually
12983 * speculate -- set the speculation size to 0.
12984 */
12985 opt[DTRACEOPT_SPECSIZE] = 0;
12986 }
12987 }
12988
12989 /*
12990 * The bare minimum size for any buffer that we're actually going to
12991 * do anything to is sizeof (uint64_t).
12992 */
12993 sz = sizeof (uint64_t);
12994
12995 if ((state->dts_needed != 0 && opt[DTRACEOPT_BUFSIZE] < sz) ||
12996 (state->dts_speculates && opt[DTRACEOPT_SPECSIZE] < sz) ||
12997 (state->dts_aggregations != NULL && opt[DTRACEOPT_AGGSIZE] < sz)) {
12998 /*
12999 * A buffer size has been explicitly set to 0 (or to a size
13000 * that will be adjusted to 0) and we need the space -- we
13001 * need to return failure. We return ENOSPC to differentiate
13002 * it from failing to allocate a buffer due to failure to meet
13003 * the reserve (for which we return E2BIG).
13004 */
13005 rval = ENOSPC;
13006 goto out;
13007 }
13008
13009 if ((rval = dtrace_state_buffers(state)) != 0)
13010 goto err;
13011
13012 if ((sz = opt[DTRACEOPT_DYNVARSIZE]) == DTRACEOPT_UNSET)
13013 sz = dtrace_dstate_defsize;
13014
13015 do {
13016 rval = dtrace_dstate_init(&state->dts_vstate.dtvs_dynvars, sz);
13017
13018 if (rval == 0)
13019 break;
13020
13021 if (opt[DTRACEOPT_BUFRESIZE] == DTRACEOPT_BUFRESIZE_MANUAL)
13022 goto err;
13023 } while (sz >>= 1);
13024
13025 opt[DTRACEOPT_DYNVARSIZE] = sz;
13026
13027 if (rval != 0)
13028 goto err;
13029
13030 if (opt[DTRACEOPT_STATUSRATE] > dtrace_statusrate_max)
13031 opt[DTRACEOPT_STATUSRATE] = dtrace_statusrate_max;
13032
13033 if (opt[DTRACEOPT_CLEANRATE] == 0)
13034 opt[DTRACEOPT_CLEANRATE] = dtrace_cleanrate_max;
13035
13036 if (opt[DTRACEOPT_CLEANRATE] < dtrace_cleanrate_min)
13037 opt[DTRACEOPT_CLEANRATE] = dtrace_cleanrate_min;
13038
13039 if (opt[DTRACEOPT_CLEANRATE] > dtrace_cleanrate_max)
13040 opt[DTRACEOPT_CLEANRATE] = dtrace_cleanrate_max;
13041
13042 hdlr.cyh_func = (cyc_func_t)dtrace_state_clean;
13043 hdlr.cyh_arg = state;
13044 hdlr.cyh_level = CY_LOW_LEVEL;
13045
13046 when.cyt_when = 0;
13047 when.cyt_interval = opt[DTRACEOPT_CLEANRATE];
13048
13049 state->dts_cleaner = cyclic_add(&hdlr, &when);
13050
13051 hdlr.cyh_func = (cyc_func_t)dtrace_state_deadman;
13052 hdlr.cyh_arg = state;
13053 hdlr.cyh_level = CY_LOW_LEVEL;
13054
13055 when.cyt_when = 0;
13056 when.cyt_interval = dtrace_deadman_interval;
13057
13058 state->dts_alive = state->dts_laststatus = dtrace_gethrtime();
13059 state->dts_deadman = cyclic_add(&hdlr, &when);
13060
13061 state->dts_activity = DTRACE_ACTIVITY_WARMUP;
13062
13063 /*
13064 * Now it's time to actually fire the BEGIN probe. We need to disable
13065 * interrupts here both to record the CPU on which we fired the BEGIN
13066 * probe (the data from this CPU will be processed first at user
13067 * level) and to manually activate the buffer for this CPU.
13068 */
13069 cookie = dtrace_interrupt_disable();
13070 *cpu = CPU->cpu_id;
13071 ASSERT(state->dts_buffer[*cpu].dtb_flags & DTRACEBUF_INACTIVE);
13072 state->dts_buffer[*cpu].dtb_flags &= ~DTRACEBUF_INACTIVE;
13073
13074 dtrace_probe(dtrace_probeid_begin,
13075 (uint64_t)(uintptr_t)state, 0, 0, 0, 0);
13076 dtrace_interrupt_enable(cookie);
13077 /*
13078 * We may have had an exit action from a BEGIN probe; only change our
13079 * state to ACTIVE if we're still in WARMUP.
13080 */
13081 ASSERT(state->dts_activity == DTRACE_ACTIVITY_WARMUP ||
13082 state->dts_activity == DTRACE_ACTIVITY_DRAINING);
13083
13084 if (state->dts_activity == DTRACE_ACTIVITY_WARMUP)
13085 state->dts_activity = DTRACE_ACTIVITY_ACTIVE;
13086
13087 /*
13088 * Regardless of whether or not now we're in ACTIVE or DRAINING, we
13089 * want each CPU to transition its principal buffer out of the
13090 * INACTIVE state. Doing this assures that no CPU will suddenly begin
13091 * processing an ECB halfway down a probe's ECB chain; all CPUs will
13092 * atomically transition from processing none of a state's ECBs to
13093 * processing all of them.
13094 */
13095 dtrace_xcall(DTRACE_CPUALL,
13096 (dtrace_xcall_t)dtrace_buffer_activate, state);
13097 goto out;
13098
13099 err:
13100 dtrace_buffer_free(state->dts_buffer);
13101 dtrace_buffer_free(state->dts_aggbuffer);
13102
13103 if ((nspec = state->dts_nspeculations) == 0) {
13104 ASSERT(state->dts_speculations == NULL);
13105 goto out;
13106 }
13107
13108 spec = state->dts_speculations;
13109 ASSERT(spec != NULL);
13110
13111 for (i = 0; i < state->dts_nspeculations; i++) {
13112 if ((buf = spec[i].dtsp_buffer) == NULL)
13113 break;
13114
13115 dtrace_buffer_free(buf);
13116 kmem_free(buf, bufsize);
13117 }
13118
13119 kmem_free(spec, nspec * sizeof (dtrace_speculation_t));
13120 state->dts_nspeculations = 0;
13121 state->dts_speculations = NULL;
13122
13123 out:
13124 mutex_exit(&dtrace_lock);
13125 mutex_exit(&cpu_lock);
13126
13127 return (rval);
13128 }
13129
13130 static int
13131 dtrace_state_stop(dtrace_state_t *state, processorid_t *cpu)
13132 {
13133 dtrace_icookie_t cookie;
13134
13135 ASSERT(MUTEX_HELD(&dtrace_lock));
13136
13137 if (state->dts_activity != DTRACE_ACTIVITY_ACTIVE &&
13138 state->dts_activity != DTRACE_ACTIVITY_DRAINING)
13139 return (EINVAL);
13140
13141 /*
13142 * We'll set the activity to DTRACE_ACTIVITY_DRAINING, and issue a sync
13143 * to be sure that every CPU has seen it. See below for the details
13144 * on why this is done.
13145 */
13146 state->dts_activity = DTRACE_ACTIVITY_DRAINING;
13147 dtrace_sync();
13148
13149 /*
13150 * By this point, it is impossible for any CPU to be still processing
13151 * with DTRACE_ACTIVITY_ACTIVE. We can thus set our activity to
13152 * DTRACE_ACTIVITY_COOLDOWN and know that we're not racing with any
13153 * other CPU in dtrace_buffer_reserve(). This allows dtrace_probe()
13154 * and callees to know that the activity is DTRACE_ACTIVITY_COOLDOWN
13155 * iff we're in the END probe.
13156 */
13157 state->dts_activity = DTRACE_ACTIVITY_COOLDOWN;
13158 dtrace_sync();
13159 ASSERT(state->dts_activity == DTRACE_ACTIVITY_COOLDOWN);
13160
13161 /*
13162 * Finally, we can release the reserve and call the END probe. We
13163 * disable interrupts across calling the END probe to allow us to
13164 * return the CPU on which we actually called the END probe. This
13165 * allows user-land to be sure that this CPU's principal buffer is
13166 * processed last.
13167 */
13168 state->dts_reserve = 0;
13169
13170 cookie = dtrace_interrupt_disable();
13171 *cpu = CPU->cpu_id;
13172 dtrace_probe(dtrace_probeid_end,
13173 (uint64_t)(uintptr_t)state, 0, 0, 0, 0);
13174 dtrace_interrupt_enable(cookie);
13175
13176 state->dts_activity = DTRACE_ACTIVITY_STOPPED;
13177 dtrace_sync();
13178
13179 return (0);
13180 }
13181
13182 static int
13183 dtrace_state_option(dtrace_state_t *state, dtrace_optid_t option,
13184 dtrace_optval_t val)
13185 {
13186 ASSERT(MUTEX_HELD(&dtrace_lock));
13187
13188 if (state->dts_activity != DTRACE_ACTIVITY_INACTIVE)
13189 return (EBUSY);
13190
13191 if (option >= DTRACEOPT_MAX)
13192 return (EINVAL);
13193
13194 if (option != DTRACEOPT_CPU && val < 0)
13195 return (EINVAL);
13196
13197 switch (option) {
13198 case DTRACEOPT_DESTRUCTIVE:
13199 if (dtrace_destructive_disallow)
13200 return (EACCES);
13201
13202 state->dts_cred.dcr_destructive = 1;
13203 break;
13204
13205 case DTRACEOPT_BUFSIZE:
13206 case DTRACEOPT_DYNVARSIZE:
13207 case DTRACEOPT_AGGSIZE:
13208 case DTRACEOPT_SPECSIZE:
13209 case DTRACEOPT_STRSIZE:
13210 if (val < 0)
13211 return (EINVAL);
13212
13213 if (val >= LONG_MAX) {
13214 /*
13215 * If this is an otherwise negative value, set it to
13216 * the highest multiple of 128m less than LONG_MAX.
13217 * Technically, we're adjusting the size without
13218 * regard to the buffer resizing policy, but in fact,
13219 * this has no effect -- if we set the buffer size to
13220 * ~LONG_MAX and the buffer policy is ultimately set to
13221 * be "manual", the buffer allocation is guaranteed to
13222 * fail, if only because the allocation requires two
13223 * buffers. (We set the the size to the highest
13224 * multiple of 128m because it ensures that the size
13225 * will remain a multiple of a megabyte when
13226 * repeatedly halved -- all the way down to 15m.)
13227 */
13228 val = LONG_MAX - (1 << 27) + 1;
13229 }
13230 }
13231
13232 state->dts_options[option] = val;
13233
13234 return (0);
13235 }
13236
13237 static void
13238 dtrace_state_destroy(dtrace_state_t *state)
13239 {
13240 dtrace_ecb_t *ecb;
13241 dtrace_vstate_t *vstate = &state->dts_vstate;
13242 minor_t minor = getminor(state->dts_dev);
13243 int i, bufsize = NCPU * sizeof (dtrace_buffer_t);
13244 dtrace_speculation_t *spec = state->dts_speculations;
13245 int nspec = state->dts_nspeculations;
13246 uint32_t match;
13247
13248 ASSERT(MUTEX_HELD(&dtrace_lock));
13249 ASSERT(MUTEX_HELD(&cpu_lock));
13250
13251 /*
13252 * First, retract any retained enablings for this state.
13253 */
13254 dtrace_enabling_retract(state);
13255 ASSERT(state->dts_nretained == 0);
13256
13257 if (state->dts_activity == DTRACE_ACTIVITY_ACTIVE ||
13258 state->dts_activity == DTRACE_ACTIVITY_DRAINING) {
13259 /*
13260 * We have managed to come into dtrace_state_destroy() on a
13261 * hot enabling -- almost certainly because of a disorderly
13262 * shutdown of a consumer. (That is, a consumer that is
13263 * exiting without having called dtrace_stop().) In this case,
13264 * we're going to set our activity to be KILLED, and then
13265 * issue a sync to be sure that everyone is out of probe
13266 * context before we start blowing away ECBs.
13267 */
13268 state->dts_activity = DTRACE_ACTIVITY_KILLED;
13269 dtrace_sync();
13270 }
13271
13272 /*
13273 * Release the credential hold we took in dtrace_state_create().
13274 */
13275 if (state->dts_cred.dcr_cred != NULL)
13276 crfree(state->dts_cred.dcr_cred);
13277
13278 /*
13279 * Now we can safely disable and destroy any enabled probes. Because
13280 * any DTRACE_PRIV_KERNEL probes may actually be slowing our progress
13281 * (especially if they're all enabled), we take two passes through the
13282 * ECBs: in the first, we disable just DTRACE_PRIV_KERNEL probes, and
13283 * in the second we disable whatever is left over.
13284 */
13285 for (match = DTRACE_PRIV_KERNEL; ; match = 0) {
13286 for (i = 0; i < state->dts_necbs; i++) {
13287 if ((ecb = state->dts_ecbs[i]) == NULL)
13288 continue;
13289
13290 if (match && ecb->dte_probe != NULL) {
13291 dtrace_probe_t *probe = ecb->dte_probe;
13292 dtrace_provider_t *prov = probe->dtpr_provider;
13293
13294 if (!(prov->dtpv_priv.dtpp_flags & match))
13295 continue;
13296 }
13297
13298 dtrace_ecb_disable(ecb);
13299 dtrace_ecb_destroy(ecb);
13300 }
13301
13302 if (!match)
13303 break;
13304 }
13305
13306 /*
13307 * Before we free the buffers, perform one more sync to assure that
13308 * every CPU is out of probe context.
13309 */
13310 dtrace_sync();
13311
13312 dtrace_buffer_free(state->dts_buffer);
13313 dtrace_buffer_free(state->dts_aggbuffer);
13314
13315 for (i = 0; i < nspec; i++)
13316 dtrace_buffer_free(spec[i].dtsp_buffer);
13317
13318 if (state->dts_cleaner != CYCLIC_NONE)
13319 cyclic_remove(state->dts_cleaner);
13320
13321 if (state->dts_deadman != CYCLIC_NONE)
13322 cyclic_remove(state->dts_deadman);
13323
13324 dtrace_dstate_fini(&vstate->dtvs_dynvars);
13325 dtrace_vstate_fini(vstate);
13326 kmem_free(state->dts_ecbs, state->dts_necbs * sizeof (dtrace_ecb_t *));
13327
13328 if (state->dts_aggregations != NULL) {
13329 #ifdef DEBUG
13330 for (i = 0; i < state->dts_naggregations; i++)
13331 ASSERT(state->dts_aggregations[i] == NULL);
13332 #endif
13333 ASSERT(state->dts_naggregations > 0);
13334 kmem_free(state->dts_aggregations,
13335 state->dts_naggregations * sizeof (dtrace_aggregation_t *));
13336 }
13337
13338 kmem_free(state->dts_buffer, bufsize);
13339 kmem_free(state->dts_aggbuffer, bufsize);
13340
13341 for (i = 0; i < nspec; i++)
13342 kmem_free(spec[i].dtsp_buffer, bufsize);
13343
13344 kmem_free(spec, nspec * sizeof (dtrace_speculation_t));
13345
13346 dtrace_format_destroy(state);
13347
13348 vmem_destroy(state->dts_aggid_arena);
13349 ddi_soft_state_free(dtrace_softstate, minor);
13350 vmem_free(dtrace_minor, (void *)(uintptr_t)minor, 1);
13351 }
13352
13353 /*
13354 * DTrace Anonymous Enabling Functions
13355 */
13356 static dtrace_state_t *
13357 dtrace_anon_grab(void)
13358 {
13359 dtrace_state_t *state;
13360
13361 ASSERT(MUTEX_HELD(&dtrace_lock));
13362
13363 if ((state = dtrace_anon.dta_state) == NULL) {
13364 ASSERT(dtrace_anon.dta_enabling == NULL);
13365 return (NULL);
13366 }
13367
13368 ASSERT(dtrace_anon.dta_enabling != NULL);
13369 ASSERT(dtrace_retained != NULL);
13370
13371 dtrace_enabling_destroy(dtrace_anon.dta_enabling);
13372 dtrace_anon.dta_enabling = NULL;
13373 dtrace_anon.dta_state = NULL;
13374
13375 return (state);
13376 }
13377
13378 static void
13379 dtrace_anon_property(void)
13380 {
13381 int i, rv;
13382 dtrace_state_t *state;
13383 dof_hdr_t *dof;
13384 char c[32]; /* enough for "dof-data-" + digits */
13385
13386 ASSERT(MUTEX_HELD(&dtrace_lock));
13387 ASSERT(MUTEX_HELD(&cpu_lock));
13388
13389 for (i = 0; ; i++) {
13390 (void) snprintf(c, sizeof (c), "dof-data-%d", i);
13391
13392 dtrace_err_verbose = 1;
13393
13394 if ((dof = dtrace_dof_property(c)) == NULL) {
13395 dtrace_err_verbose = 0;
13396 break;
13397 }
13398
13399 /*
13400 * We want to create anonymous state, so we need to transition
13401 * the kernel debugger to indicate that DTrace is active. If
13402 * this fails (e.g. because the debugger has modified text in
13403 * some way), we won't continue with the processing.
13404 */
13405 if (kdi_dtrace_set(KDI_DTSET_DTRACE_ACTIVATE) != 0) {
13406 cmn_err(CE_NOTE, "kernel debugger active; anonymous "
13407 "enabling ignored.");
13408 dtrace_dof_destroy(dof);
13409 break;
13410 }
13411
13412 /*
13413 * If we haven't allocated an anonymous state, we'll do so now.
13414 */
13415 if ((state = dtrace_anon.dta_state) == NULL) {
13416 state = dtrace_state_create(NULL, NULL);
13417 dtrace_anon.dta_state = state;
13418
13419 if (state == NULL) {
13420 /*
13421 * This basically shouldn't happen: the only
13422 * failure mode from dtrace_state_create() is a
13423 * failure of ddi_soft_state_zalloc() that
13424 * itself should never happen. Still, the
13425 * interface allows for a failure mode, and
13426 * we want to fail as gracefully as possible:
13427 * we'll emit an error message and cease
13428 * processing anonymous state in this case.
13429 */
13430 cmn_err(CE_WARN, "failed to create "
13431 "anonymous state");
13432 dtrace_dof_destroy(dof);
13433 break;
13434 }
13435 }
13436
13437 rv = dtrace_dof_slurp(dof, &state->dts_vstate, CRED(),
13438 &dtrace_anon.dta_enabling, 0, B_TRUE);
13439
13440 if (rv == 0)
13441 rv = dtrace_dof_options(dof, state);
13442
13443 dtrace_err_verbose = 0;
13444 dtrace_dof_destroy(dof);
13445
13446 if (rv != 0) {
13447 /*
13448 * This is malformed DOF; chuck any anonymous state
13449 * that we created.
13450 */
13451 ASSERT(dtrace_anon.dta_enabling == NULL);
13452 dtrace_state_destroy(state);
13453 dtrace_anon.dta_state = NULL;
13454 break;
13455 }
13456
13457 ASSERT(dtrace_anon.dta_enabling != NULL);
13458 }
13459
13460 if (dtrace_anon.dta_enabling != NULL) {
13461 int rval;
13462
13463 /*
13464 * dtrace_enabling_retain() can only fail because we are
13465 * trying to retain more enablings than are allowed -- but
13466 * we only have one anonymous enabling, and we are guaranteed
13467 * to be allowed at least one retained enabling; we assert
13468 * that dtrace_enabling_retain() returns success.
13469 */
13470 rval = dtrace_enabling_retain(dtrace_anon.dta_enabling);
13471 ASSERT(rval == 0);
13472
13473 dtrace_enabling_dump(dtrace_anon.dta_enabling);
13474 }
13475 }
13476
13477 /*
13478 * DTrace Helper Functions
13479 */
13480 static void
13481 dtrace_helper_trace(dtrace_helper_action_t *helper,
13482 dtrace_mstate_t *mstate, dtrace_vstate_t *vstate, int where)
13483 {
13484 uint32_t size, next, nnext, i;
13485 dtrace_helptrace_t *ent;
13486 uint16_t flags = cpu_core[CPU->cpu_id].cpuc_dtrace_flags;
13487
13488 if (!dtrace_helptrace_enabled)
13489 return;
13490
13491 ASSERT(vstate->dtvs_nlocals <= dtrace_helptrace_nlocals);
13492
13493 /*
13494 * What would a tracing framework be without its own tracing
13495 * framework? (Well, a hell of a lot simpler, for starters...)
13496 */
13497 size = sizeof (dtrace_helptrace_t) + dtrace_helptrace_nlocals *
13498 sizeof (uint64_t) - sizeof (uint64_t);
13499
13500 /*
13501 * Iterate until we can allocate a slot in the trace buffer.
13502 */
13503 do {
13504 next = dtrace_helptrace_next;
13505
13506 if (next + size < dtrace_helptrace_bufsize) {
13507 nnext = next + size;
13508 } else {
13509 nnext = size;
13510 }
13511 } while (dtrace_cas32(&dtrace_helptrace_next, next, nnext) != next);
13512
13513 /*
13514 * We have our slot; fill it in.
13515 */
13516 if (nnext == size)
13517 next = 0;
13518
13519 ent = (dtrace_helptrace_t *)&dtrace_helptrace_buffer[next];
13520 ent->dtht_helper = helper;
13521 ent->dtht_where = where;
13522 ent->dtht_nlocals = vstate->dtvs_nlocals;
13523
13524 ent->dtht_fltoffs = (mstate->dtms_present & DTRACE_MSTATE_FLTOFFS) ?
13525 mstate->dtms_fltoffs : -1;
13526 ent->dtht_fault = DTRACE_FLAGS2FLT(flags);
13527 ent->dtht_illval = cpu_core[CPU->cpu_id].cpuc_dtrace_illval;
13528
13529 for (i = 0; i < vstate->dtvs_nlocals; i++) {
13530 dtrace_statvar_t *svar;
13531
13532 if ((svar = vstate->dtvs_locals[i]) == NULL)
13533 continue;
13534
13535 ASSERT(svar->dtsv_size >= NCPU * sizeof (uint64_t));
13536 ent->dtht_locals[i] =
13537 ((uint64_t *)(uintptr_t)svar->dtsv_data)[CPU->cpu_id];
13538 }
13539 }
13540
13541 static uint64_t
13542 dtrace_helper(int which, dtrace_mstate_t *mstate,
13543 dtrace_state_t *state, uint64_t arg0, uint64_t arg1)
13544 {
13545 uint16_t *flags = &cpu_core[CPU->cpu_id].cpuc_dtrace_flags;
13546 uint64_t sarg0 = mstate->dtms_arg[0];
13547 uint64_t sarg1 = mstate->dtms_arg[1];
13548 uint64_t rval;
13549 dtrace_helpers_t *helpers = curproc->p_dtrace_helpers;
13550 dtrace_helper_action_t *helper;
13551 dtrace_vstate_t *vstate;
13552 dtrace_difo_t *pred;
13553 int i, trace = dtrace_helptrace_enabled;
13554
13555 ASSERT(which >= 0 && which < DTRACE_NHELPER_ACTIONS);
13556
13557 if (helpers == NULL)
13558 return (0);
13559
13560 if ((helper = helpers->dthps_actions[which]) == NULL)
13561 return (0);
13562
13563 vstate = &helpers->dthps_vstate;
13564 mstate->dtms_arg[0] = arg0;
13565 mstate->dtms_arg[1] = arg1;
13566
13567 /*
13568 * Now iterate over each helper. If its predicate evaluates to 'true',
13569 * we'll call the corresponding actions. Note that the below calls
13570 * to dtrace_dif_emulate() may set faults in machine state. This is
13571 * okay: our caller (the outer dtrace_dif_emulate()) will simply plow
13572 * the stored DIF offset with its own (which is the desired behavior).
13573 * Also, note the calls to dtrace_dif_emulate() may allocate scratch
13574 * from machine state; this is okay, too.
13575 */
13576 for (; helper != NULL; helper = helper->dtha_next) {
13577 if ((pred = helper->dtha_predicate) != NULL) {
13578 if (trace)
13579 dtrace_helper_trace(helper, mstate, vstate, 0);
13580
13581 if (!dtrace_dif_emulate(pred, mstate, vstate, state))
13582 goto next;
13583
13584 if (*flags & CPU_DTRACE_FAULT)
13585 goto err;
13586 }
13587
13588 for (i = 0; i < helper->dtha_nactions; i++) {
13589 if (trace)
13590 dtrace_helper_trace(helper,
13591 mstate, vstate, i + 1);
13592
13593 rval = dtrace_dif_emulate(helper->dtha_actions[i],
13594 mstate, vstate, state);
13595
13596 if (*flags & CPU_DTRACE_FAULT)
13597 goto err;
13598 }
13599
13600 next:
13601 if (trace)
13602 dtrace_helper_trace(helper, mstate, vstate,
13603 DTRACE_HELPTRACE_NEXT);
13604 }
13605
13606 if (trace)
13607 dtrace_helper_trace(helper, mstate, vstate,
13608 DTRACE_HELPTRACE_DONE);
13609
13610 /*
13611 * Restore the arg0 that we saved upon entry.
13612 */
13613 mstate->dtms_arg[0] = sarg0;
13614 mstate->dtms_arg[1] = sarg1;
13615
13616 return (rval);
13617
13618 err:
13619 if (trace)
13620 dtrace_helper_trace(helper, mstate, vstate,
13621 DTRACE_HELPTRACE_ERR);
13622
13623 /*
13624 * Restore the arg0 that we saved upon entry.
13625 */
13626 mstate->dtms_arg[0] = sarg0;
13627 mstate->dtms_arg[1] = sarg1;
13628
13629 return (NULL);
13630 }
13631
13632 static void
13633 dtrace_helper_action_destroy(dtrace_helper_action_t *helper,
13634 dtrace_vstate_t *vstate)
13635 {
13636 int i;
13637
13638 if (helper->dtha_predicate != NULL)
13639 dtrace_difo_release(helper->dtha_predicate, vstate);
13640
13641 for (i = 0; i < helper->dtha_nactions; i++) {
13642 ASSERT(helper->dtha_actions[i] != NULL);
13643 dtrace_difo_release(helper->dtha_actions[i], vstate);
13644 }
13645
13646 kmem_free(helper->dtha_actions,
13647 helper->dtha_nactions * sizeof (dtrace_difo_t *));
13648 kmem_free(helper, sizeof (dtrace_helper_action_t));
13649 }
13650
13651 static int
13652 dtrace_helper_destroygen(int gen)
13653 {
13654 proc_t *p = curproc;
13655 dtrace_helpers_t *help = p->p_dtrace_helpers;
13656 dtrace_vstate_t *vstate;
13657 int i;
13658
13659 ASSERT(MUTEX_HELD(&dtrace_lock));
13660
13661 if (help == NULL || gen > help->dthps_generation)
13662 return (EINVAL);
13663
13664 vstate = &help->dthps_vstate;
13665
13666 for (i = 0; i < DTRACE_NHELPER_ACTIONS; i++) {
13667 dtrace_helper_action_t *last = NULL, *h, *next;
13668
13669 for (h = help->dthps_actions[i]; h != NULL; h = next) {
13670 next = h->dtha_next;
13671
13672 if (h->dtha_generation == gen) {
13673 if (last != NULL) {
13674 last->dtha_next = next;
13675 } else {
13676 help->dthps_actions[i] = next;
13677 }
13678
13679 dtrace_helper_action_destroy(h, vstate);
13680 } else {
13681 last = h;
13682 }
13683 }
13684 }
13685
13686 /*
13687 * Interate until we've cleared out all helper providers with the
13688 * given generation number.
13689 */
13690 for (;;) {
13691 dtrace_helper_provider_t *prov;
13692
13693 /*
13694 * Look for a helper provider with the right generation. We
13695 * have to start back at the beginning of the list each time
13696 * because we drop dtrace_lock. It's unlikely that we'll make
13697 * more than two passes.
13698 */
13699 for (i = 0; i < help->dthps_nprovs; i++) {
13700 prov = help->dthps_provs[i];
13701
13702 if (prov->dthp_generation == gen)
13703 break;
13704 }
13705
13706 /*
13707 * If there were no matches, we're done.
13708 */
13709 if (i == help->dthps_nprovs)
13710 break;
13711
13712 /*
13713 * Move the last helper provider into this slot.
13714 */
13715 help->dthps_nprovs--;
13716 help->dthps_provs[i] = help->dthps_provs[help->dthps_nprovs];
13717 help->dthps_provs[help->dthps_nprovs] = NULL;
13718
13719 mutex_exit(&dtrace_lock);
13720
13721 /*
13722 * If we have a meta provider, remove this helper provider.
13723 */
13724 mutex_enter(&dtrace_meta_lock);
13725 if (dtrace_meta_pid != NULL) {
13726 ASSERT(dtrace_deferred_pid == NULL);
13727 dtrace_helper_provider_remove(&prov->dthp_prov,
13728 p->p_pid);
13729 }
13730 mutex_exit(&dtrace_meta_lock);
13731
13732 dtrace_helper_provider_destroy(prov);
13733
13734 mutex_enter(&dtrace_lock);
13735 }
13736
13737 return (0);
13738 }
13739
13740 static int
13741 dtrace_helper_validate(dtrace_helper_action_t *helper)
13742 {
13743 int err = 0, i;
13744 dtrace_difo_t *dp;
13745
13746 if ((dp = helper->dtha_predicate) != NULL)
13747 err += dtrace_difo_validate_helper(dp);
13748
13749 for (i = 0; i < helper->dtha_nactions; i++)
13750 err += dtrace_difo_validate_helper(helper->dtha_actions[i]);
13751
13752 return (err == 0);
13753 }
13754
13755 static int
13756 dtrace_helper_action_add(int which, dtrace_ecbdesc_t *ep)
13757 {
13758 dtrace_helpers_t *help;
13759 dtrace_helper_action_t *helper, *last;
13760 dtrace_actdesc_t *act;
13761 dtrace_vstate_t *vstate;
13762 dtrace_predicate_t *pred;
13763 int count = 0, nactions = 0, i;
13764
13765 if (which < 0 || which >= DTRACE_NHELPER_ACTIONS)
13766 return (EINVAL);
13767
13768 help = curproc->p_dtrace_helpers;
13769 last = help->dthps_actions[which];
13770 vstate = &help->dthps_vstate;
13771
13772 for (count = 0; last != NULL; last = last->dtha_next) {
13773 count++;
13774 if (last->dtha_next == NULL)
13775 break;
13776 }
13777
13778 /*
13779 * If we already have dtrace_helper_actions_max helper actions for this
13780 * helper action type, we'll refuse to add a new one.
13781 */
13782 if (count >= dtrace_helper_actions_max)
13783 return (ENOSPC);
13784
13785 helper = kmem_zalloc(sizeof (dtrace_helper_action_t), KM_SLEEP);
13786 helper->dtha_generation = help->dthps_generation;
13787
13788 if ((pred = ep->dted_pred.dtpdd_predicate) != NULL) {
13789 ASSERT(pred->dtp_difo != NULL);
13790 dtrace_difo_hold(pred->dtp_difo);
13791 helper->dtha_predicate = pred->dtp_difo;
13792 }
13793
13794 for (act = ep->dted_action; act != NULL; act = act->dtad_next) {
13795 if (act->dtad_kind != DTRACEACT_DIFEXPR)
13796 goto err;
13797
13798 if (act->dtad_difo == NULL)
13799 goto err;
13800
13801 nactions++;
13802 }
13803
13804 helper->dtha_actions = kmem_zalloc(sizeof (dtrace_difo_t *) *
13805 (helper->dtha_nactions = nactions), KM_SLEEP);
13806
13807 for (act = ep->dted_action, i = 0; act != NULL; act = act->dtad_next) {
13808 dtrace_difo_hold(act->dtad_difo);
13809 helper->dtha_actions[i++] = act->dtad_difo;
13810 }
13811
13812 if (!dtrace_helper_validate(helper))
13813 goto err;
13814
13815 if (last == NULL) {
13816 help->dthps_actions[which] = helper;
13817 } else {
13818 last->dtha_next = helper;
13819 }
13820
13821 if (vstate->dtvs_nlocals > dtrace_helptrace_nlocals) {
13822 dtrace_helptrace_nlocals = vstate->dtvs_nlocals;
13823 dtrace_helptrace_next = 0;
13824 }
13825
13826 return (0);
13827 err:
13828 dtrace_helper_action_destroy(helper, vstate);
13829 return (EINVAL);
13830 }
13831
13832 static void
13833 dtrace_helper_provider_register(proc_t *p, dtrace_helpers_t *help,
13834 dof_helper_t *dofhp)
13835 {
13836 ASSERT(MUTEX_NOT_HELD(&dtrace_lock));
13837
13838 mutex_enter(&dtrace_meta_lock);
13839 mutex_enter(&dtrace_lock);
13840
13841 if (!dtrace_attached() || dtrace_meta_pid == NULL) {
13842 /*
13843 * If the dtrace module is loaded but not attached, or if
13844 * there aren't isn't a meta provider registered to deal with
13845 * these provider descriptions, we need to postpone creating
13846 * the actual providers until later.
13847 */
13848
13849 if (help->dthps_next == NULL && help->dthps_prev == NULL &&
13850 dtrace_deferred_pid != help) {
13851 help->dthps_deferred = 1;
13852 help->dthps_pid = p->p_pid;
13853 help->dthps_next = dtrace_deferred_pid;
13854 help->dthps_prev = NULL;
13855 if (dtrace_deferred_pid != NULL)
13856 dtrace_deferred_pid->dthps_prev = help;
13857 dtrace_deferred_pid = help;
13858 }
13859
13860 mutex_exit(&dtrace_lock);
13861
13862 } else if (dofhp != NULL) {
13863 /*
13864 * If the dtrace module is loaded and we have a particular
13865 * helper provider description, pass that off to the
13866 * meta provider.
13867 */
13868
13869 mutex_exit(&dtrace_lock);
13870
13871 dtrace_helper_provide(dofhp, p->p_pid);
13872
13873 } else {
13874 /*
13875 * Otherwise, just pass all the helper provider descriptions
13876 * off to the meta provider.
13877 */
13878
13879 int i;
13880 mutex_exit(&dtrace_lock);
13881
13882 for (i = 0; i < help->dthps_nprovs; i++) {
13883 dtrace_helper_provide(&help->dthps_provs[i]->dthp_prov,
13884 p->p_pid);
13885 }
13886 }
13887
13888 mutex_exit(&dtrace_meta_lock);
13889 }
13890
13891 static int
13892 dtrace_helper_provider_add(dof_helper_t *dofhp, int gen)
13893 {
13894 dtrace_helpers_t *help;
13895 dtrace_helper_provider_t *hprov, **tmp_provs;
13896 uint_t tmp_maxprovs, i;
13897
13898 ASSERT(MUTEX_HELD(&dtrace_lock));
13899
13900 help = curproc->p_dtrace_helpers;
13901 ASSERT(help != NULL);
13902
13903 /*
13904 * If we already have dtrace_helper_providers_max helper providers,
13905 * we're refuse to add a new one.
13906 */
13907 if (help->dthps_nprovs >= dtrace_helper_providers_max)
13908 return (ENOSPC);
13909
13910 /*
13911 * Check to make sure this isn't a duplicate.
13912 */
13913 for (i = 0; i < help->dthps_nprovs; i++) {
13914 if (dofhp->dofhp_addr ==
13915 help->dthps_provs[i]->dthp_prov.dofhp_addr)
13916 return (EALREADY);
13917 }
13918
13919 hprov = kmem_zalloc(sizeof (dtrace_helper_provider_t), KM_SLEEP);
13920 hprov->dthp_prov = *dofhp;
13921 hprov->dthp_ref = 1;
13922 hprov->dthp_generation = gen;
13923
13924 /*
13925 * Allocate a bigger table for helper providers if it's already full.
13926 */
13927 if (help->dthps_maxprovs == help->dthps_nprovs) {
13928 tmp_maxprovs = help->dthps_maxprovs;
13929 tmp_provs = help->dthps_provs;
13930
13931 if (help->dthps_maxprovs == 0)
13932 help->dthps_maxprovs = 2;
13933 else
13934 help->dthps_maxprovs *= 2;
13935 if (help->dthps_maxprovs > dtrace_helper_providers_max)
13936 help->dthps_maxprovs = dtrace_helper_providers_max;
13937
13938 ASSERT(tmp_maxprovs < help->dthps_maxprovs);
13939
13940 help->dthps_provs = kmem_zalloc(help->dthps_maxprovs *
13941 sizeof (dtrace_helper_provider_t *), KM_SLEEP);
13942
13943 if (tmp_provs != NULL) {
13944 bcopy(tmp_provs, help->dthps_provs, tmp_maxprovs *
13945 sizeof (dtrace_helper_provider_t *));
13946 kmem_free(tmp_provs, tmp_maxprovs *
13947 sizeof (dtrace_helper_provider_t *));
13948 }
13949 }
13950
13951 help->dthps_provs[help->dthps_nprovs] = hprov;
13952 help->dthps_nprovs++;
13953
13954 return (0);
13955 }
13956
13957 static void
13958 dtrace_helper_provider_destroy(dtrace_helper_provider_t *hprov)
13959 {
13960 mutex_enter(&dtrace_lock);
13961
13962 if (--hprov->dthp_ref == 0) {
13963 dof_hdr_t *dof;
13964 mutex_exit(&dtrace_lock);
13965 dof = (dof_hdr_t *)(uintptr_t)hprov->dthp_prov.dofhp_dof;
13966 dtrace_dof_destroy(dof);
13967 kmem_free(hprov, sizeof (dtrace_helper_provider_t));
13968 } else {
13969 mutex_exit(&dtrace_lock);
13970 }
13971 }
13972
13973 static int
13974 dtrace_helper_provider_validate(dof_hdr_t *dof, dof_sec_t *sec)
13975 {
13976 uintptr_t daddr = (uintptr_t)dof;
13977 dof_sec_t *str_sec, *prb_sec, *arg_sec, *off_sec, *enoff_sec;
13978 dof_provider_t *provider;
13979 dof_probe_t *probe;
13980 uint8_t *arg;
13981 char *strtab, *typestr;
13982 dof_stridx_t typeidx;
13983 size_t typesz;
13984 uint_t nprobes, j, k;
13985
13986 ASSERT(sec->dofs_type == DOF_SECT_PROVIDER);
13987
13988 if (sec->dofs_offset & (sizeof (uint_t) - 1)) {
13989 dtrace_dof_error(dof, "misaligned section offset");
13990 return (-1);
13991 }
13992
13993 /*
13994 * The section needs to be large enough to contain the DOF provider
13995 * structure appropriate for the given version.
13996 */
13997 if (sec->dofs_size <
13998 ((dof->dofh_ident[DOF_ID_VERSION] == DOF_VERSION_1) ?
13999 offsetof(dof_provider_t, dofpv_prenoffs) :
14000 sizeof (dof_provider_t))) {
14001 dtrace_dof_error(dof, "provider section too small");
14002 return (-1);
14003 }
14004
14005 provider = (dof_provider_t *)(uintptr_t)(daddr + sec->dofs_offset);
14006 str_sec = dtrace_dof_sect(dof, DOF_SECT_STRTAB, provider->dofpv_strtab);
14007 prb_sec = dtrace_dof_sect(dof, DOF_SECT_PROBES, provider->dofpv_probes);
14008 arg_sec = dtrace_dof_sect(dof, DOF_SECT_PRARGS, provider->dofpv_prargs);
14009 off_sec = dtrace_dof_sect(dof, DOF_SECT_PROFFS, provider->dofpv_proffs);
14010
14011 if (str_sec == NULL || prb_sec == NULL ||
14012 arg_sec == NULL || off_sec == NULL)
14013 return (-1);
14014
14015 enoff_sec = NULL;
14016
14017 if (dof->dofh_ident[DOF_ID_VERSION] != DOF_VERSION_1 &&
14018 provider->dofpv_prenoffs != DOF_SECT_NONE &&
14019 (enoff_sec = dtrace_dof_sect(dof, DOF_SECT_PRENOFFS,
14020 provider->dofpv_prenoffs)) == NULL)
14021 return (-1);
14022
14023 strtab = (char *)(uintptr_t)(daddr + str_sec->dofs_offset);
14024
14025 if (provider->dofpv_name >= str_sec->dofs_size ||
14026 strlen(strtab + provider->dofpv_name) >= DTRACE_PROVNAMELEN) {
14027 dtrace_dof_error(dof, "invalid provider name");
14028 return (-1);
14029 }
14030
14031 if (prb_sec->dofs_entsize == 0 ||
14032 prb_sec->dofs_entsize > prb_sec->dofs_size) {
14033 dtrace_dof_error(dof, "invalid entry size");
14034 return (-1);
14035 }
14036
14037 if (prb_sec->dofs_entsize & (sizeof (uintptr_t) - 1)) {
14038 dtrace_dof_error(dof, "misaligned entry size");
14039 return (-1);
14040 }
14041
14042 if (off_sec->dofs_entsize != sizeof (uint32_t)) {
14043 dtrace_dof_error(dof, "invalid entry size");
14044 return (-1);
14045 }
14046
14047 if (off_sec->dofs_offset & (sizeof (uint32_t) - 1)) {
14048 dtrace_dof_error(dof, "misaligned section offset");
14049 return (-1);
14050 }
14051
14052 if (arg_sec->dofs_entsize != sizeof (uint8_t)) {
14053 dtrace_dof_error(dof, "invalid entry size");
14054 return (-1);
14055 }
14056
14057 arg = (uint8_t *)(uintptr_t)(daddr + arg_sec->dofs_offset);
14058
14059 nprobes = prb_sec->dofs_size / prb_sec->dofs_entsize;
14060
14061 /*
14062 * Take a pass through the probes to check for errors.
14063 */
14064 for (j = 0; j < nprobes; j++) {
14065 probe = (dof_probe_t *)(uintptr_t)(daddr +
14066 prb_sec->dofs_offset + j * prb_sec->dofs_entsize);
14067
14068 if (probe->dofpr_func >= str_sec->dofs_size) {
14069 dtrace_dof_error(dof, "invalid function name");
14070 return (-1);
14071 }
14072
14073 if (strlen(strtab + probe->dofpr_func) >= DTRACE_FUNCNAMELEN) {
14074 dtrace_dof_error(dof, "function name too long");
14075 return (-1);
14076 }
14077
14078 if (probe->dofpr_name >= str_sec->dofs_size ||
14079 strlen(strtab + probe->dofpr_name) >= DTRACE_NAMELEN) {
14080 dtrace_dof_error(dof, "invalid probe name");
14081 return (-1);
14082 }
14083
14084 /*
14085 * The offset count must not wrap the index, and the offsets
14086 * must also not overflow the section's data.
14087 */
14088 if (probe->dofpr_offidx + probe->dofpr_noffs <
14089 probe->dofpr_offidx ||
14090 (probe->dofpr_offidx + probe->dofpr_noffs) *
14091 off_sec->dofs_entsize > off_sec->dofs_size) {
14092 dtrace_dof_error(dof, "invalid probe offset");
14093 return (-1);
14094 }
14095
14096 if (dof->dofh_ident[DOF_ID_VERSION] != DOF_VERSION_1) {
14097 /*
14098 * If there's no is-enabled offset section, make sure
14099 * there aren't any is-enabled offsets. Otherwise
14100 * perform the same checks as for probe offsets
14101 * (immediately above).
14102 */
14103 if (enoff_sec == NULL) {
14104 if (probe->dofpr_enoffidx != 0 ||
14105 probe->dofpr_nenoffs != 0) {
14106 dtrace_dof_error(dof, "is-enabled "
14107 "offsets with null section");
14108 return (-1);
14109 }
14110 } else if (probe->dofpr_enoffidx +
14111 probe->dofpr_nenoffs < probe->dofpr_enoffidx ||
14112 (probe->dofpr_enoffidx + probe->dofpr_nenoffs) *
14113 enoff_sec->dofs_entsize > enoff_sec->dofs_size) {
14114 dtrace_dof_error(dof, "invalid is-enabled "
14115 "offset");
14116 return (-1);
14117 }
14118
14119 if (probe->dofpr_noffs + probe->dofpr_nenoffs == 0) {
14120 dtrace_dof_error(dof, "zero probe and "
14121 "is-enabled offsets");
14122 return (-1);
14123 }
14124 } else if (probe->dofpr_noffs == 0) {
14125 dtrace_dof_error(dof, "zero probe offsets");
14126 return (-1);
14127 }
14128
14129 if (probe->dofpr_argidx + probe->dofpr_xargc <
14130 probe->dofpr_argidx ||
14131 (probe->dofpr_argidx + probe->dofpr_xargc) *
14132 arg_sec->dofs_entsize > arg_sec->dofs_size) {
14133 dtrace_dof_error(dof, "invalid args");
14134 return (-1);
14135 }
14136
14137 typeidx = probe->dofpr_nargv;
14138 typestr = strtab + probe->dofpr_nargv;
14139 for (k = 0; k < probe->dofpr_nargc; k++) {
14140 if (typeidx >= str_sec->dofs_size) {
14141 dtrace_dof_error(dof, "bad "
14142 "native argument type");
14143 return (-1);
14144 }
14145
14146 typesz = strlen(typestr) + 1;
14147 if (typesz > DTRACE_ARGTYPELEN) {
14148 dtrace_dof_error(dof, "native "
14149 "argument type too long");
14150 return (-1);
14151 }
14152 typeidx += typesz;
14153 typestr += typesz;
14154 }
14155
14156 typeidx = probe->dofpr_xargv;
14157 typestr = strtab + probe->dofpr_xargv;
14158 for (k = 0; k < probe->dofpr_xargc; k++) {
14159 if (arg[probe->dofpr_argidx + k] > probe->dofpr_nargc) {
14160 dtrace_dof_error(dof, "bad "
14161 "native argument index");
14162 return (-1);
14163 }
14164
14165 if (typeidx >= str_sec->dofs_size) {
14166 dtrace_dof_error(dof, "bad "
14167 "translated argument type");
14168 return (-1);
14169 }
14170
14171 typesz = strlen(typestr) + 1;
14172 if (typesz > DTRACE_ARGTYPELEN) {
14173 dtrace_dof_error(dof, "translated argument "
14174 "type too long");
14175 return (-1);
14176 }
14177
14178 typeidx += typesz;
14179 typestr += typesz;
14180 }
14181 }
14182
14183 return (0);
14184 }
14185
14186 static int
14187 dtrace_helper_slurp(dof_hdr_t *dof, dof_helper_t *dhp)
14188 {
14189 dtrace_helpers_t *help;
14190 dtrace_vstate_t *vstate;
14191 dtrace_enabling_t *enab = NULL;
14192 int i, gen, rv, nhelpers = 0, nprovs = 0, destroy = 1;
14193 uintptr_t daddr = (uintptr_t)dof;
14194
14195 ASSERT(MUTEX_HELD(&dtrace_lock));
14196
14197 if ((help = curproc->p_dtrace_helpers) == NULL)
14198 help = dtrace_helpers_create(curproc);
14199
14200 vstate = &help->dthps_vstate;
14201
14202 if ((rv = dtrace_dof_slurp(dof, vstate, NULL, &enab,
14203 dhp != NULL ? dhp->dofhp_addr : 0, B_FALSE)) != 0) {
14204 dtrace_dof_destroy(dof);
14205 return (rv);
14206 }
14207
14208 /*
14209 * Look for helper providers and validate their descriptions.
14210 */
14211 if (dhp != NULL) {
14212 for (i = 0; i < dof->dofh_secnum; i++) {
14213 dof_sec_t *sec = (dof_sec_t *)(uintptr_t)(daddr +
14214 dof->dofh_secoff + i * dof->dofh_secsize);
14215
14216 if (sec->dofs_type != DOF_SECT_PROVIDER)
14217 continue;
14218
14219 if (dtrace_helper_provider_validate(dof, sec) != 0) {
14220 dtrace_enabling_destroy(enab);
14221 dtrace_dof_destroy(dof);
14222 return (-1);
14223 }
14224
14225 nprovs++;
14226 }
14227 }
14228
14229 /*
14230 * Now we need to walk through the ECB descriptions in the enabling.
14231 */
14232 for (i = 0; i < enab->dten_ndesc; i++) {
14233 dtrace_ecbdesc_t *ep = enab->dten_desc[i];
14234 dtrace_probedesc_t *desc = &ep->dted_probe;
14235
14236 if (strcmp(desc->dtpd_provider, "dtrace") != 0)
14237 continue;
14238
14239 if (strcmp(desc->dtpd_mod, "helper") != 0)
14240 continue;
14241
14242 if (strcmp(desc->dtpd_func, "ustack") != 0)
14243 continue;
14244
14245 if ((rv = dtrace_helper_action_add(DTRACE_HELPER_ACTION_USTACK,
14246 ep)) != 0) {
14247 /*
14248 * Adding this helper action failed -- we are now going
14249 * to rip out the entire generation and return failure.
14250 */
14251 (void) dtrace_helper_destroygen(help->dthps_generation);
14252 dtrace_enabling_destroy(enab);
14253 dtrace_dof_destroy(dof);
14254 return (-1);
14255 }
14256
14257 nhelpers++;
14258 }
14259
14260 if (nhelpers < enab->dten_ndesc)
14261 dtrace_dof_error(dof, "unmatched helpers");
14262
14263 gen = help->dthps_generation++;
14264 dtrace_enabling_destroy(enab);
14265
14266 if (dhp != NULL && nprovs > 0) {
14267 dhp->dofhp_dof = (uint64_t)(uintptr_t)dof;
14268 if (dtrace_helper_provider_add(dhp, gen) == 0) {
14269 mutex_exit(&dtrace_lock);
14270 dtrace_helper_provider_register(curproc, help, dhp);
14271 mutex_enter(&dtrace_lock);
14272
14273 destroy = 0;
14274 }
14275 }
14276
14277 if (destroy)
14278 dtrace_dof_destroy(dof);
14279
14280 return (gen);
14281 }
14282
14283 static dtrace_helpers_t *
14284 dtrace_helpers_create(proc_t *p)
14285 {
14286 dtrace_helpers_t *help;
14287
14288 ASSERT(MUTEX_HELD(&dtrace_lock));
14289 ASSERT(p->p_dtrace_helpers == NULL);
14290
14291 help = kmem_zalloc(sizeof (dtrace_helpers_t), KM_SLEEP);
14292 help->dthps_actions = kmem_zalloc(sizeof (dtrace_helper_action_t *) *
14293 DTRACE_NHELPER_ACTIONS, KM_SLEEP);
14294
14295 p->p_dtrace_helpers = help;
14296 dtrace_helpers++;
14297
14298 return (help);
14299 }
14300
14301 static void
14302 dtrace_helpers_destroy(void)
14303 {
14304 dtrace_helpers_t *help;
14305 dtrace_vstate_t *vstate;
14306 proc_t *p = curproc;
14307 int i;
14308
14309 mutex_enter(&dtrace_lock);
14310
14311 ASSERT(p->p_dtrace_helpers != NULL);
14312 ASSERT(dtrace_helpers > 0);
14313
14314 help = p->p_dtrace_helpers;
14315 vstate = &help->dthps_vstate;
14316
14317 /*
14318 * We're now going to lose the help from this process.
14319 */
14320 p->p_dtrace_helpers = NULL;
14321 dtrace_sync();
14322
14323 /*
14324 * Destory the helper actions.
14325 */
14326 for (i = 0; i < DTRACE_NHELPER_ACTIONS; i++) {
14327 dtrace_helper_action_t *h, *next;
14328
14329 for (h = help->dthps_actions[i]; h != NULL; h = next) {
14330 next = h->dtha_next;
14331 dtrace_helper_action_destroy(h, vstate);
14332 h = next;
14333 }
14334 }
14335
14336 mutex_exit(&dtrace_lock);
14337
14338 /*
14339 * Destroy the helper providers.
14340 */
14341 if (help->dthps_maxprovs > 0) {
14342 mutex_enter(&dtrace_meta_lock);
14343 if (dtrace_meta_pid != NULL) {
14344 ASSERT(dtrace_deferred_pid == NULL);
14345
14346 for (i = 0; i < help->dthps_nprovs; i++) {
14347 dtrace_helper_provider_remove(
14348 &help->dthps_provs[i]->dthp_prov, p->p_pid);
14349 }
14350 } else {
14351 mutex_enter(&dtrace_lock);
14352 ASSERT(help->dthps_deferred == 0 ||
14353 help->dthps_next != NULL ||
14354 help->dthps_prev != NULL ||
14355 help == dtrace_deferred_pid);
14356
14357 /*
14358 * Remove the helper from the deferred list.
14359 */
14360 if (help->dthps_next != NULL)
14361 help->dthps_next->dthps_prev = help->dthps_prev;
14362 if (help->dthps_prev != NULL)
14363 help->dthps_prev->dthps_next = help->dthps_next;
14364 if (dtrace_deferred_pid == help) {
14365 dtrace_deferred_pid = help->dthps_next;
14366 ASSERT(help->dthps_prev == NULL);
14367 }
14368
14369 mutex_exit(&dtrace_lock);
14370 }
14371
14372 mutex_exit(&dtrace_meta_lock);
14373
14374 for (i = 0; i < help->dthps_nprovs; i++) {
14375 dtrace_helper_provider_destroy(help->dthps_provs[i]);
14376 }
14377
14378 kmem_free(help->dthps_provs, help->dthps_maxprovs *
14379 sizeof (dtrace_helper_provider_t *));
14380 }
14381
14382 mutex_enter(&dtrace_lock);
14383
14384 dtrace_vstate_fini(&help->dthps_vstate);
14385 kmem_free(help->dthps_actions,
14386 sizeof (dtrace_helper_action_t *) * DTRACE_NHELPER_ACTIONS);
14387 kmem_free(help, sizeof (dtrace_helpers_t));
14388
14389 --dtrace_helpers;
14390 mutex_exit(&dtrace_lock);
14391 }
14392
14393 static void
14394 dtrace_helpers_duplicate(proc_t *from, proc_t *to)
14395 {
14396 dtrace_helpers_t *help, *newhelp;
14397 dtrace_helper_action_t *helper, *new, *last;
14398 dtrace_difo_t *dp;
14399 dtrace_vstate_t *vstate;
14400 int i, j, sz, hasprovs = 0;
14401
14402 mutex_enter(&dtrace_lock);
14403 ASSERT(from->p_dtrace_helpers != NULL);
14404 ASSERT(dtrace_helpers > 0);
14405
14406 help = from->p_dtrace_helpers;
14407 newhelp = dtrace_helpers_create(to);
14408 ASSERT(to->p_dtrace_helpers != NULL);
14409
14410 newhelp->dthps_generation = help->dthps_generation;
14411 vstate = &newhelp->dthps_vstate;
14412
14413 /*
14414 * Duplicate the helper actions.
14415 */
14416 for (i = 0; i < DTRACE_NHELPER_ACTIONS; i++) {
14417 if ((helper = help->dthps_actions[i]) == NULL)
14418 continue;
14419
14420 for (last = NULL; helper != NULL; helper = helper->dtha_next) {
14421 new = kmem_zalloc(sizeof (dtrace_helper_action_t),
14422 KM_SLEEP);
14423 new->dtha_generation = helper->dtha_generation;
14424
14425 if ((dp = helper->dtha_predicate) != NULL) {
14426 dp = dtrace_difo_duplicate(dp, vstate);
14427 new->dtha_predicate = dp;
14428 }
14429
14430 new->dtha_nactions = helper->dtha_nactions;
14431 sz = sizeof (dtrace_difo_t *) * new->dtha_nactions;
14432 new->dtha_actions = kmem_alloc(sz, KM_SLEEP);
14433
14434 for (j = 0; j < new->dtha_nactions; j++) {
14435 dtrace_difo_t *dp = helper->dtha_actions[j];
14436
14437 ASSERT(dp != NULL);
14438 dp = dtrace_difo_duplicate(dp, vstate);
14439 new->dtha_actions[j] = dp;
14440 }
14441
14442 if (last != NULL) {
14443 last->dtha_next = new;
14444 } else {
14445 newhelp->dthps_actions[i] = new;
14446 }
14447
14448 last = new;
14449 }
14450 }
14451
14452 /*
14453 * Duplicate the helper providers and register them with the
14454 * DTrace framework.
14455 */
14456 if (help->dthps_nprovs > 0) {
14457 newhelp->dthps_nprovs = help->dthps_nprovs;
14458 newhelp->dthps_maxprovs = help->dthps_nprovs;
14459 newhelp->dthps_provs = kmem_alloc(newhelp->dthps_nprovs *
14460 sizeof (dtrace_helper_provider_t *), KM_SLEEP);
14461 for (i = 0; i < newhelp->dthps_nprovs; i++) {
14462 newhelp->dthps_provs[i] = help->dthps_provs[i];
14463 newhelp->dthps_provs[i]->dthp_ref++;
14464 }
14465
14466 hasprovs = 1;
14467 }
14468
14469 mutex_exit(&dtrace_lock);
14470
14471 if (hasprovs)
14472 dtrace_helper_provider_register(to, newhelp, NULL);
14473 }
14474
14475 /*
14476 * DTrace Hook Functions
14477 */
14478 static void
14479 dtrace_module_loaded(struct modctl *ctl)
14480 {
14481 dtrace_provider_t *prv;
14482
14483 mutex_enter(&dtrace_provider_lock);
14484 mutex_enter(&mod_lock);
14485
14486 ASSERT(ctl->mod_busy);
14487
14488 /*
14489 * We're going to call each providers per-module provide operation
14490 * specifying only this module.
14491 */
14492 for (prv = dtrace_provider; prv != NULL; prv = prv->dtpv_next)
14493 prv->dtpv_pops.dtps_provide_module(prv->dtpv_arg, ctl);
14494
14495 mutex_exit(&mod_lock);
14496 mutex_exit(&dtrace_provider_lock);
14497
14498 /*
14499 * If we have any retained enablings, we need to match against them.
14500 * Enabling probes requires that cpu_lock be held, and we cannot hold
14501 * cpu_lock here -- it is legal for cpu_lock to be held when loading a
14502 * module. (In particular, this happens when loading scheduling
14503 * classes.) So if we have any retained enablings, we need to dispatch
14504 * our task queue to do the match for us.
14505 */
14506 mutex_enter(&dtrace_lock);
14507
14508 if (dtrace_retained == NULL) {
14509 mutex_exit(&dtrace_lock);
14510 return;
14511 }
14512
14513 (void) taskq_dispatch(dtrace_taskq,
14514 (task_func_t *)dtrace_enabling_matchall, NULL, TQ_SLEEP);
14515
14516 mutex_exit(&dtrace_lock);
14517
14518 /*
14519 * And now, for a little heuristic sleaze: in general, we want to
14520 * match modules as soon as they load. However, we cannot guarantee
14521 * this, because it would lead us to the lock ordering violation
14522 * outlined above. The common case, of course, is that cpu_lock is
14523 * _not_ held -- so we delay here for a clock tick, hoping that that's
14524 * long enough for the task queue to do its work. If it's not, it's
14525 * not a serious problem -- it just means that the module that we
14526 * just loaded may not be immediately instrumentable.
14527 */
14528 delay(1);
14529 }
14530
14531 static void
14532 dtrace_module_unloaded(struct modctl *ctl)
14533 {
14534 dtrace_probe_t template, *probe, *first, *next;
14535 dtrace_provider_t *prov;
14536
14537 template.dtpr_mod = ctl->mod_modname;
14538
14539 mutex_enter(&dtrace_provider_lock);
14540 mutex_enter(&mod_lock);
14541 mutex_enter(&dtrace_lock);
14542
14543 if (dtrace_bymod == NULL) {
14544 /*
14545 * The DTrace module is loaded (obviously) but not attached;
14546 * we don't have any work to do.
14547 */
14548 mutex_exit(&dtrace_provider_lock);
14549 mutex_exit(&mod_lock);
14550 mutex_exit(&dtrace_lock);
14551 return;
14552 }
14553
14554 for (probe = first = dtrace_hash_lookup(dtrace_bymod, &template);
14555 probe != NULL; probe = probe->dtpr_nextmod) {
14556 if (probe->dtpr_ecb != NULL) {
14557 mutex_exit(&dtrace_provider_lock);
14558 mutex_exit(&mod_lock);
14559 mutex_exit(&dtrace_lock);
14560
14561 /*
14562 * This shouldn't _actually_ be possible -- we're
14563 * unloading a module that has an enabled probe in it.
14564 * (It's normally up to the provider to make sure that
14565 * this can't happen.) However, because dtps_enable()
14566 * doesn't have a failure mode, there can be an
14567 * enable/unload race. Upshot: we don't want to
14568 * assert, but we're not going to disable the
14569 * probe, either.
14570 */
14571 if (dtrace_err_verbose) {
14572 cmn_err(CE_WARN, "unloaded module '%s' had "
14573 "enabled probes", ctl->mod_modname);
14574 }
14575
14576 return;
14577 }
14578 }
14579
14580 probe = first;
14581
14582 for (first = NULL; probe != NULL; probe = next) {
14583 ASSERT(dtrace_probes[probe->dtpr_id - 1] == probe);
14584
14585 dtrace_probes[probe->dtpr_id - 1] = NULL;
14586
14587 next = probe->dtpr_nextmod;
14588 dtrace_hash_remove(dtrace_bymod, probe);
14589 dtrace_hash_remove(dtrace_byfunc, probe);
14590 dtrace_hash_remove(dtrace_byname, probe);
14591
14592 if (first == NULL) {
14593 first = probe;
14594 probe->dtpr_nextmod = NULL;
14595 } else {
14596 probe->dtpr_nextmod = first;
14597 first = probe;
14598 }
14599 }
14600
14601 /*
14602 * We've removed all of the module's probes from the hash chains and
14603 * from the probe array. Now issue a dtrace_sync() to be sure that
14604 * everyone has cleared out from any probe array processing.
14605 */
14606 dtrace_sync();
14607
14608 for (probe = first; probe != NULL; probe = first) {
14609 first = probe->dtpr_nextmod;
14610 prov = probe->dtpr_provider;
14611 prov->dtpv_pops.dtps_destroy(prov->dtpv_arg, probe->dtpr_id,
14612 probe->dtpr_arg);
14613 kmem_free(probe->dtpr_mod, strlen(probe->dtpr_mod) + 1);
14614 kmem_free(probe->dtpr_func, strlen(probe->dtpr_func) + 1);
14615 kmem_free(probe->dtpr_name, strlen(probe->dtpr_name) + 1);
14616 vmem_free(dtrace_arena, (void *)(uintptr_t)probe->dtpr_id, 1);
14617 kmem_free(probe, sizeof (dtrace_probe_t));
14618 }
14619
14620 mutex_exit(&dtrace_lock);
14621 mutex_exit(&mod_lock);
14622 mutex_exit(&dtrace_provider_lock);
14623 }
14624
14625 void
14626 dtrace_suspend(void)
14627 {
14628 dtrace_probe_foreach(offsetof(dtrace_pops_t, dtps_suspend));
14629 }
14630
14631 void
14632 dtrace_resume(void)
14633 {
14634 dtrace_probe_foreach(offsetof(dtrace_pops_t, dtps_resume));
14635 }
14636
14637 static int
14638 dtrace_cpu_setup(cpu_setup_t what, processorid_t cpu)
14639 {
14640 ASSERT(MUTEX_HELD(&cpu_lock));
14641 mutex_enter(&dtrace_lock);
14642
14643 switch (what) {
14644 case CPU_CONFIG: {
14645 dtrace_state_t *state;
14646 dtrace_optval_t *opt, rs, c;
14647
14648 /*
14649 * For now, we only allocate a new buffer for anonymous state.
14650 */
14651 if ((state = dtrace_anon.dta_state) == NULL)
14652 break;
14653
14654 if (state->dts_activity != DTRACE_ACTIVITY_ACTIVE)
14655 break;
14656
14657 opt = state->dts_options;
14658 c = opt[DTRACEOPT_CPU];
14659
14660 if (c != DTRACE_CPUALL && c != DTRACEOPT_UNSET && c != cpu)
14661 break;
14662
14663 /*
14664 * Regardless of what the actual policy is, we're going to
14665 * temporarily set our resize policy to be manual. We're
14666 * also going to temporarily set our CPU option to denote
14667 * the newly configured CPU.
14668 */
14669 rs = opt[DTRACEOPT_BUFRESIZE];
14670 opt[DTRACEOPT_BUFRESIZE] = DTRACEOPT_BUFRESIZE_MANUAL;
14671 opt[DTRACEOPT_CPU] = (dtrace_optval_t)cpu;
14672
14673 (void) dtrace_state_buffers(state);
14674
14675 opt[DTRACEOPT_BUFRESIZE] = rs;
14676 opt[DTRACEOPT_CPU] = c;
14677
14678 break;
14679 }
14680
14681 case CPU_UNCONFIG:
14682 /*
14683 * We don't free the buffer in the CPU_UNCONFIG case. (The
14684 * buffer will be freed when the consumer exits.)
14685 */
14686 break;
14687
14688 default:
14689 break;
14690 }
14691
14692 mutex_exit(&dtrace_lock);
14693 return (0);
14694 }
14695
14696 static void
14697 dtrace_cpu_setup_initial(processorid_t cpu)
14698 {
14699 (void) dtrace_cpu_setup(CPU_CONFIG, cpu);
14700 }
14701
14702 static void
14703 dtrace_toxrange_add(uintptr_t base, uintptr_t limit)
14704 {
14705 if (dtrace_toxranges >= dtrace_toxranges_max) {
14706 int osize, nsize;
14707 dtrace_toxrange_t *range;
14708
14709 osize = dtrace_toxranges_max * sizeof (dtrace_toxrange_t);
14710
14711 if (osize == 0) {
14712 ASSERT(dtrace_toxrange == NULL);
14713 ASSERT(dtrace_toxranges_max == 0);
14714 dtrace_toxranges_max = 1;
14715 } else {
14716 dtrace_toxranges_max <<= 1;
14717 }
14718
14719 nsize = dtrace_toxranges_max * sizeof (dtrace_toxrange_t);
14720 range = kmem_zalloc(nsize, KM_SLEEP);
14721
14722 if (dtrace_toxrange != NULL) {
14723 ASSERT(osize != 0);
14724 bcopy(dtrace_toxrange, range, osize);
14725 kmem_free(dtrace_toxrange, osize);
14726 }
14727
14728 dtrace_toxrange = range;
14729 }
14730
14731 ASSERT(dtrace_toxrange[dtrace_toxranges].dtt_base == NULL);
14732 ASSERT(dtrace_toxrange[dtrace_toxranges].dtt_limit == NULL);
14733
14734 dtrace_toxrange[dtrace_toxranges].dtt_base = base;
14735 dtrace_toxrange[dtrace_toxranges].dtt_limit = limit;
14736 dtrace_toxranges++;
14737 }
14738
14739 /*
14740 * DTrace Driver Cookbook Functions
14741 */
14742 /*ARGSUSED*/
14743 static int
14744 dtrace_attach(dev_info_t *devi, ddi_attach_cmd_t cmd)
14745 {
14746 dtrace_provider_id_t id;
14747 dtrace_state_t *state = NULL;
14748 dtrace_enabling_t *enab;
14749
14750 mutex_enter(&cpu_lock);
14751 mutex_enter(&dtrace_provider_lock);
14752 mutex_enter(&dtrace_lock);
14753
14754 if (ddi_soft_state_init(&dtrace_softstate,
14755 sizeof (dtrace_state_t), 0) != 0) {
14756 cmn_err(CE_NOTE, "/dev/dtrace failed to initialize soft state");
14757 mutex_exit(&cpu_lock);
14758 mutex_exit(&dtrace_provider_lock);
14759 mutex_exit(&dtrace_lock);
14760 return (DDI_FAILURE);
14761 }
14762
14763 if (ddi_create_minor_node(devi, DTRACEMNR_DTRACE, S_IFCHR,
14764 DTRACEMNRN_DTRACE, DDI_PSEUDO, NULL) == DDI_FAILURE ||
14765 ddi_create_minor_node(devi, DTRACEMNR_HELPER, S_IFCHR,
14766 DTRACEMNRN_HELPER, DDI_PSEUDO, NULL) == DDI_FAILURE) {
14767 cmn_err(CE_NOTE, "/dev/dtrace couldn't create minor nodes");
14768 ddi_remove_minor_node(devi, NULL);
14769 ddi_soft_state_fini(&dtrace_softstate);
14770 mutex_exit(&cpu_lock);
14771 mutex_exit(&dtrace_provider_lock);
14772 mutex_exit(&dtrace_lock);
14773 return (DDI_FAILURE);
14774 }
14775
14776 ddi_report_dev(devi);
14777 dtrace_devi = devi;
14778
14779 dtrace_modload = dtrace_module_loaded;
14780 dtrace_modunload = dtrace_module_unloaded;
14781 dtrace_cpu_init = dtrace_cpu_setup_initial;
14782 dtrace_helpers_cleanup = dtrace_helpers_destroy;
14783 dtrace_helpers_fork = dtrace_helpers_duplicate;
14784 dtrace_cpustart_init = dtrace_suspend;
14785 dtrace_cpustart_fini = dtrace_resume;
14786 dtrace_debugger_init = dtrace_suspend;
14787 dtrace_debugger_fini = dtrace_resume;
14788
14789 register_cpu_setup_func((cpu_setup_func_t *)dtrace_cpu_setup, NULL);
14790
14791 ASSERT(MUTEX_HELD(&cpu_lock));
14792
14793 dtrace_arena = vmem_create("dtrace", (void *)1, UINT32_MAX, 1,
14794 NULL, NULL, NULL, 0, VM_SLEEP | VMC_IDENTIFIER);
14795 dtrace_minor = vmem_create("dtrace_minor", (void *)DTRACEMNRN_CLONE,
14796 UINT32_MAX - DTRACEMNRN_CLONE, 1, NULL, NULL, NULL, 0,
14797 VM_SLEEP | VMC_IDENTIFIER);
14798 dtrace_taskq = taskq_create("dtrace_taskq", 1, maxclsyspri,
14799 1, INT_MAX, 0);
14800
14801 dtrace_state_cache = kmem_cache_create("dtrace_state_cache",
14802 sizeof (dtrace_dstate_percpu_t) * NCPU, DTRACE_STATE_ALIGN,
14803 NULL, NULL, NULL, NULL, NULL, 0);
14804
14805 ASSERT(MUTEX_HELD(&cpu_lock));
14806 dtrace_bymod = dtrace_hash_create(offsetof(dtrace_probe_t, dtpr_mod),
14807 offsetof(dtrace_probe_t, dtpr_nextmod),
14808 offsetof(dtrace_probe_t, dtpr_prevmod));
14809
14810 dtrace_byfunc = dtrace_hash_create(offsetof(dtrace_probe_t, dtpr_func),
14811 offsetof(dtrace_probe_t, dtpr_nextfunc),
14812 offsetof(dtrace_probe_t, dtpr_prevfunc));
14813
14814 dtrace_byname = dtrace_hash_create(offsetof(dtrace_probe_t, dtpr_name),
14815 offsetof(dtrace_probe_t, dtpr_nextname),
14816 offsetof(dtrace_probe_t, dtpr_prevname));
14817
14818 if (dtrace_retain_max < 1) {
14819 cmn_err(CE_WARN, "illegal value (%lu) for dtrace_retain_max; "
14820 "setting to 1", dtrace_retain_max);
14821 dtrace_retain_max = 1;
14822 }
14823
14824 /*
14825 * Now discover our toxic ranges.
14826 */
14827 dtrace_toxic_ranges(dtrace_toxrange_add);
14828
14829 /*
14830 * Before we register ourselves as a provider to our own framework,
14831 * we would like to assert that dtrace_provider is NULL -- but that's
14832 * not true if we were loaded as a dependency of a DTrace provider.
14833 * Once we've registered, we can assert that dtrace_provider is our
14834 * pseudo provider.
14835 */
14836 (void) dtrace_register("dtrace", &dtrace_provider_attr,
14837 DTRACE_PRIV_NONE, 0, &dtrace_provider_ops, NULL, &id);
14838
14839 ASSERT(dtrace_provider != NULL);
14840 ASSERT((dtrace_provider_id_t)dtrace_provider == id);
14841
14842 dtrace_probeid_begin = dtrace_probe_create((dtrace_provider_id_t)
14843 dtrace_provider, NULL, NULL, "BEGIN", 0, NULL);
14844 dtrace_probeid_end = dtrace_probe_create((dtrace_provider_id_t)
14845 dtrace_provider, NULL, NULL, "END", 0, NULL);
14846 dtrace_probeid_error = dtrace_probe_create((dtrace_provider_id_t)
14847 dtrace_provider, NULL, NULL, "ERROR", 1, NULL);
14848
14849 dtrace_anon_property();
14850 mutex_exit(&cpu_lock);
14851
14852 /*
14853 * If DTrace helper tracing is enabled, we need to allocate the
14854 * trace buffer and initialize the values.
14855 */
14856 if (dtrace_helptrace_enabled) {
14857 ASSERT(dtrace_helptrace_buffer == NULL);
14858 dtrace_helptrace_buffer =
14859 kmem_zalloc(dtrace_helptrace_bufsize, KM_SLEEP);
14860 dtrace_helptrace_next = 0;
14861 }
14862
14863 /*
14864 * If there are already providers, we must ask them to provide their
14865 * probes, and then match any anonymous enabling against them. Note
14866 * that there should be no other retained enablings at this time:
14867 * the only retained enablings at this time should be the anonymous
14868 * enabling.
14869 */
14870 if (dtrace_anon.dta_enabling != NULL) {
14871 ASSERT(dtrace_retained == dtrace_anon.dta_enabling);
14872
14873 dtrace_enabling_provide(NULL);
14874 state = dtrace_anon.dta_state;
14875
14876 /*
14877 * We couldn't hold cpu_lock across the above call to
14878 * dtrace_enabling_provide(), but we must hold it to actually
14879 * enable the probes. We have to drop all of our locks, pick
14880 * up cpu_lock, and regain our locks before matching the
14881 * retained anonymous enabling.
14882 */
14883 mutex_exit(&dtrace_lock);
14884 mutex_exit(&dtrace_provider_lock);
14885
14886 mutex_enter(&cpu_lock);
14887 mutex_enter(&dtrace_provider_lock);
14888 mutex_enter(&dtrace_lock);
14889
14890 if ((enab = dtrace_anon.dta_enabling) != NULL)
14891 (void) dtrace_enabling_match(enab, NULL);
14892
14893 mutex_exit(&cpu_lock);
14894 }
14895
14896 mutex_exit(&dtrace_lock);
14897 mutex_exit(&dtrace_provider_lock);
14898
14899 if (state != NULL) {
14900 /*
14901 * If we created any anonymous state, set it going now.
14902 */
14903 (void) dtrace_state_go(state, &dtrace_anon.dta_beganon);
14904 }
14905
14906 return (DDI_SUCCESS);
14907 }
14908
14909 /*ARGSUSED*/
14910 static int
14911 dtrace_open(dev_t *devp, int flag, int otyp, cred_t *cred_p)
14912 {
14913 dtrace_state_t *state;
14914 uint32_t priv;
14915 uid_t uid;
14916 zoneid_t zoneid;
14917
14918 if (getminor(*devp) == DTRACEMNRN_HELPER)
14919 return (0);
14920
14921 /*
14922 * If this wasn't an open with the "helper" minor, then it must be
14923 * the "dtrace" minor.
14924 */
14925 if (getminor(*devp) != DTRACEMNRN_DTRACE)
14926 return (ENXIO);
14927
14928 /*
14929 * If no DTRACE_PRIV_* bits are set in the credential, then the
14930 * caller lacks sufficient permission to do anything with DTrace.
14931 */
14932 dtrace_cred2priv(cred_p, &priv, &uid, &zoneid);
14933 if (priv == DTRACE_PRIV_NONE)
14934 return (EACCES);
14935
14936 /*
14937 * Ask all providers to provide all their probes.
14938 */
14939 mutex_enter(&dtrace_provider_lock);
14940 dtrace_probe_provide(NULL, NULL);
14941 mutex_exit(&dtrace_provider_lock);
14942
14943 mutex_enter(&cpu_lock);
14944 mutex_enter(&dtrace_lock);
14945 dtrace_opens++;
14946 dtrace_membar_producer();
14947
14948 /*
14949 * If the kernel debugger is active (that is, if the kernel debugger
14950 * modified text in some way), we won't allow the open.
14951 */
14952 if (kdi_dtrace_set(KDI_DTSET_DTRACE_ACTIVATE) != 0) {
14953 dtrace_opens--;
14954 mutex_exit(&cpu_lock);
14955 mutex_exit(&dtrace_lock);
14956 return (EBUSY);
14957 }
14958
14959 state = dtrace_state_create(devp, cred_p);
14960 mutex_exit(&cpu_lock);
14961
14962 if (state == NULL) {
14963 if (--dtrace_opens == 0 && dtrace_anon.dta_enabling == NULL)
14964 (void) kdi_dtrace_set(KDI_DTSET_DTRACE_DEACTIVATE);
14965 mutex_exit(&dtrace_lock);
14966 return (EAGAIN);
14967 }
14968
14969 mutex_exit(&dtrace_lock);
14970
14971 return (0);
14972 }
14973
14974 /*ARGSUSED*/
14975 static int
14976 dtrace_close(dev_t dev, int flag, int otyp, cred_t *cred_p)
14977 {
14978 minor_t minor = getminor(dev);
14979 dtrace_state_t *state;
14980
14981 if (minor == DTRACEMNRN_HELPER)
14982 return (0);
14983
14984 state = ddi_get_soft_state(dtrace_softstate, minor);
14985
14986 mutex_enter(&cpu_lock);
14987 mutex_enter(&dtrace_lock);
14988
14989 if (state->dts_anon) {
14990 /*
14991 * There is anonymous state. Destroy that first.
14992 */
14993 ASSERT(dtrace_anon.dta_state == NULL);
14994 dtrace_state_destroy(state->dts_anon);
14995 }
14996
14997 dtrace_state_destroy(state);
14998 ASSERT(dtrace_opens > 0);
14999
15000 /*
15001 * Only relinquish control of the kernel debugger interface when there
15002 * are no consumers and no anonymous enablings.
15003 */
15004 if (--dtrace_opens == 0 && dtrace_anon.dta_enabling == NULL)
15005 (void) kdi_dtrace_set(KDI_DTSET_DTRACE_DEACTIVATE);
15006
15007 mutex_exit(&dtrace_lock);
15008 mutex_exit(&cpu_lock);
15009
15010 return (0);
15011 }
15012
15013 /*ARGSUSED*/
15014 static int
15015 dtrace_ioctl_helper(int cmd, intptr_t arg, int *rv)
15016 {
15017 int rval;
15018 dof_helper_t help, *dhp = NULL;
15019
15020 switch (cmd) {
15021 case DTRACEHIOC_ADDDOF:
15022 if (copyin((void *)arg, &help, sizeof (help)) != 0) {
15023 dtrace_dof_error(NULL, "failed to copyin DOF helper");
15024 return (EFAULT);
15025 }
15026
15027 dhp = &help;
15028 arg = (intptr_t)help.dofhp_dof;
15029 /*FALLTHROUGH*/
15030
15031 case DTRACEHIOC_ADD: {
15032 dof_hdr_t *dof = dtrace_dof_copyin(arg, &rval);
15033
15034 if (dof == NULL)
15035 return (rval);
15036
15037 mutex_enter(&dtrace_lock);
15038
15039 /*
15040 * dtrace_helper_slurp() takes responsibility for the dof --
15041 * it may free it now or it may save it and free it later.
15042 */
15043 if ((rval = dtrace_helper_slurp(dof, dhp)) != -1) {
15044 *rv = rval;
15045 rval = 0;
15046 } else {
15047 rval = EINVAL;
15048 }
15049
15050 mutex_exit(&dtrace_lock);
15051 return (rval);
15052 }
15053
15054 case DTRACEHIOC_REMOVE: {
15055 mutex_enter(&dtrace_lock);
15056 rval = dtrace_helper_destroygen(arg);
15057 mutex_exit(&dtrace_lock);
15058
15059 return (rval);
15060 }
15061
15062 default:
15063 break;
15064 }
15065
15066 return (ENOTTY);
15067 }
15068
15069 /*ARGSUSED*/
15070 static int
15071 dtrace_ioctl(dev_t dev, int cmd, intptr_t arg, int md, cred_t *cr, int *rv)
15072 {
15073 minor_t minor = getminor(dev);
15074 dtrace_state_t *state;
15075 int rval;
15076
15077 if (minor == DTRACEMNRN_HELPER)
15078 return (dtrace_ioctl_helper(cmd, arg, rv));
15079
15080 state = ddi_get_soft_state(dtrace_softstate, minor);
15081
15082 if (state->dts_anon) {
15083 ASSERT(dtrace_anon.dta_state == NULL);
15084 state = state->dts_anon;
15085 }
15086
15087 switch (cmd) {
15088 case DTRACEIOC_PROVIDER: {
15089 dtrace_providerdesc_t pvd;
15090 dtrace_provider_t *pvp;
15091
15092 if (copyin((void *)arg, &pvd, sizeof (pvd)) != 0)
15093 return (EFAULT);
15094
15095 pvd.dtvd_name[DTRACE_PROVNAMELEN - 1] = '\0';
15096 mutex_enter(&dtrace_provider_lock);
15097
15098 for (pvp = dtrace_provider; pvp != NULL; pvp = pvp->dtpv_next) {
15099 if (strcmp(pvp->dtpv_name, pvd.dtvd_name) == 0)
15100 break;
15101 }
15102
15103 mutex_exit(&dtrace_provider_lock);
15104
15105 if (pvp == NULL)
15106 return (ESRCH);
15107
15108 bcopy(&pvp->dtpv_priv, &pvd.dtvd_priv, sizeof (dtrace_ppriv_t));
15109 bcopy(&pvp->dtpv_attr, &pvd.dtvd_attr, sizeof (dtrace_pattr_t));
15110 if (copyout(&pvd, (void *)arg, sizeof (pvd)) != 0)
15111 return (EFAULT);
15112
15113 return (0);
15114 }
15115
15116 case DTRACEIOC_EPROBE: {
15117 dtrace_eprobedesc_t epdesc;
15118 dtrace_ecb_t *ecb;
15119 dtrace_action_t *act;
15120 void *buf;
15121 size_t size;
15122 uintptr_t dest;
15123 int nrecs;
15124
15125 if (copyin((void *)arg, &epdesc, sizeof (epdesc)) != 0)
15126 return (EFAULT);
15127
15128 mutex_enter(&dtrace_lock);
15129
15130 if ((ecb = dtrace_epid2ecb(state, epdesc.dtepd_epid)) == NULL) {
15131 mutex_exit(&dtrace_lock);
15132 return (EINVAL);
15133 }
15134
15135 if (ecb->dte_probe == NULL) {
15136 mutex_exit(&dtrace_lock);
15137 return (EINVAL);
15138 }
15139
15140 epdesc.dtepd_probeid = ecb->dte_probe->dtpr_id;
15141 epdesc.dtepd_uarg = ecb->dte_uarg;
15142 epdesc.dtepd_size = ecb->dte_size;
15143
15144 nrecs = epdesc.dtepd_nrecs;
15145 epdesc.dtepd_nrecs = 0;
15146 for (act = ecb->dte_action; act != NULL; act = act->dta_next) {
15147 if (DTRACEACT_ISAGG(act->dta_kind) || act->dta_intuple)
15148 continue;
15149
15150 epdesc.dtepd_nrecs++;
15151 }
15152
15153 /*
15154 * Now that we have the size, we need to allocate a temporary
15155 * buffer in which to store the complete description. We need
15156 * the temporary buffer to be able to drop dtrace_lock()
15157 * across the copyout(), below.
15158 */
15159 size = sizeof (dtrace_eprobedesc_t) +
15160 (epdesc.dtepd_nrecs * sizeof (dtrace_recdesc_t));
15161
15162 buf = kmem_alloc(size, KM_SLEEP);
15163 dest = (uintptr_t)buf;
15164
15165 bcopy(&epdesc, (void *)dest, sizeof (epdesc));
15166 dest += offsetof(dtrace_eprobedesc_t, dtepd_rec[0]);
15167
15168 for (act = ecb->dte_action; act != NULL; act = act->dta_next) {
15169 if (DTRACEACT_ISAGG(act->dta_kind) || act->dta_intuple)
15170 continue;
15171
15172 if (nrecs-- == 0)
15173 break;
15174
15175 bcopy(&act->dta_rec, (void *)dest,
15176 sizeof (dtrace_recdesc_t));
15177 dest += sizeof (dtrace_recdesc_t);
15178 }
15179
15180 mutex_exit(&dtrace_lock);
15181
15182 if (copyout(buf, (void *)arg, dest - (uintptr_t)buf) != 0) {
15183 kmem_free(buf, size);
15184 return (EFAULT);
15185 }
15186
15187 kmem_free(buf, size);
15188 return (0);
15189 }
15190
15191 case DTRACEIOC_AGGDESC: {
15192 dtrace_aggdesc_t aggdesc;
15193 dtrace_action_t *act;
15194 dtrace_aggregation_t *agg;
15195 int nrecs;
15196 uint32_t offs;
15197 dtrace_recdesc_t *lrec;
15198 void *buf;
15199 size_t size;
15200 uintptr_t dest;
15201
15202 if (copyin((void *)arg, &aggdesc, sizeof (aggdesc)) != 0)
15203 return (EFAULT);
15204
15205 mutex_enter(&dtrace_lock);
15206
15207 if ((agg = dtrace_aggid2agg(state, aggdesc.dtagd_id)) == NULL) {
15208 mutex_exit(&dtrace_lock);
15209 return (EINVAL);
15210 }
15211
15212 aggdesc.dtagd_epid = agg->dtag_ecb->dte_epid;
15213
15214 nrecs = aggdesc.dtagd_nrecs;
15215 aggdesc.dtagd_nrecs = 0;
15216
15217 offs = agg->dtag_base;
15218 lrec = &agg->dtag_action.dta_rec;
15219 aggdesc.dtagd_size = lrec->dtrd_offset + lrec->dtrd_size - offs;
15220
15221 for (act = agg->dtag_first; ; act = act->dta_next) {
15222 ASSERT(act->dta_intuple ||
15223 DTRACEACT_ISAGG(act->dta_kind));
15224
15225 /*
15226 * If this action has a record size of zero, it
15227 * denotes an argument to the aggregating action.
15228 * Because the presence of this record doesn't (or
15229 * shouldn't) affect the way the data is interpreted,
15230 * we don't copy it out to save user-level the
15231 * confusion of dealing with a zero-length record.
15232 */
15233 if (act->dta_rec.dtrd_size == 0) {
15234 ASSERT(agg->dtag_hasarg);
15235 continue;
15236 }
15237
15238 aggdesc.dtagd_nrecs++;
15239
15240 if (act == &agg->dtag_action)
15241 break;
15242 }
15243
15244 /*
15245 * Now that we have the size, we need to allocate a temporary
15246 * buffer in which to store the complete description. We need
15247 * the temporary buffer to be able to drop dtrace_lock()
15248 * across the copyout(), below.
15249 */
15250 size = sizeof (dtrace_aggdesc_t) +
15251 (aggdesc.dtagd_nrecs * sizeof (dtrace_recdesc_t));
15252
15253 buf = kmem_alloc(size, KM_SLEEP);
15254 dest = (uintptr_t)buf;
15255
15256 bcopy(&aggdesc, (void *)dest, sizeof (aggdesc));
15257 dest += offsetof(dtrace_aggdesc_t, dtagd_rec[0]);
15258
15259 for (act = agg->dtag_first; ; act = act->dta_next) {
15260 dtrace_recdesc_t rec = act->dta_rec;
15261
15262 /*
15263 * See the comment in the above loop for why we pass
15264 * over zero-length records.
15265 */
15266 if (rec.dtrd_size == 0) {
15267 ASSERT(agg->dtag_hasarg);
15268 continue;
15269 }
15270
15271 if (nrecs-- == 0)
15272 break;
15273
15274 rec.dtrd_offset -= offs;
15275 bcopy(&rec, (void *)dest, sizeof (rec));
15276 dest += sizeof (dtrace_recdesc_t);
15277
15278 if (act == &agg->dtag_action)
15279 break;
15280 }
15281
15282 mutex_exit(&dtrace_lock);
15283
15284 if (copyout(buf, (void *)arg, dest - (uintptr_t)buf) != 0) {
15285 kmem_free(buf, size);
15286 return (EFAULT);
15287 }
15288
15289 kmem_free(buf, size);
15290 return (0);
15291 }
15292
15293 case DTRACEIOC_ENABLE: {
15294 dof_hdr_t *dof;
15295 dtrace_enabling_t *enab = NULL;
15296 dtrace_vstate_t *vstate;
15297 int err = 0;
15298
15299 *rv = 0;
15300
15301 /*
15302 * If a NULL argument has been passed, we take this as our
15303 * cue to reevaluate our enablings.
15304 */
15305 if (arg == NULL) {
15306 dtrace_enabling_matchall();
15307
15308 return (0);
15309 }
15310
15311 if ((dof = dtrace_dof_copyin(arg, &rval)) == NULL)
15312 return (rval);
15313
15314 mutex_enter(&cpu_lock);
15315 mutex_enter(&dtrace_lock);
15316 vstate = &state->dts_vstate;
15317
15318 if (state->dts_activity != DTRACE_ACTIVITY_INACTIVE) {
15319 mutex_exit(&dtrace_lock);
15320 mutex_exit(&cpu_lock);
15321 dtrace_dof_destroy(dof);
15322 return (EBUSY);
15323 }
15324
15325 if (dtrace_dof_slurp(dof, vstate, cr, &enab, 0, B_TRUE) != 0) {
15326 mutex_exit(&dtrace_lock);
15327 mutex_exit(&cpu_lock);
15328 dtrace_dof_destroy(dof);
15329 return (EINVAL);
15330 }
15331
15332 if ((rval = dtrace_dof_options(dof, state)) != 0) {
15333 dtrace_enabling_destroy(enab);
15334 mutex_exit(&dtrace_lock);
15335 mutex_exit(&cpu_lock);
15336 dtrace_dof_destroy(dof);
15337 return (rval);
15338 }
15339
15340 if ((err = dtrace_enabling_match(enab, rv)) == 0) {
15341 err = dtrace_enabling_retain(enab);
15342 } else {
15343 dtrace_enabling_destroy(enab);
15344 }
15345
15346 mutex_exit(&cpu_lock);
15347 mutex_exit(&dtrace_lock);
15348 dtrace_dof_destroy(dof);
15349
15350 return (err);
15351 }
15352
15353 case DTRACEIOC_REPLICATE: {
15354 dtrace_repldesc_t desc;
15355 dtrace_probedesc_t *match = &desc.dtrpd_match;
15356 dtrace_probedesc_t *create = &desc.dtrpd_create;
15357 int err;
15358
15359 if (copyin((void *)arg, &desc, sizeof (desc)) != 0)
15360 return (EFAULT);
15361
15362 match->dtpd_provider[DTRACE_PROVNAMELEN - 1] = '\0';
15363 match->dtpd_mod[DTRACE_MODNAMELEN - 1] = '\0';
15364 match->dtpd_func[DTRACE_FUNCNAMELEN - 1] = '\0';
15365 match->dtpd_name[DTRACE_NAMELEN - 1] = '\0';
15366
15367 create->dtpd_provider[DTRACE_PROVNAMELEN - 1] = '\0';
15368 create->dtpd_mod[DTRACE_MODNAMELEN - 1] = '\0';
15369 create->dtpd_func[DTRACE_FUNCNAMELEN - 1] = '\0';
15370 create->dtpd_name[DTRACE_NAMELEN - 1] = '\0';
15371
15372 mutex_enter(&dtrace_lock);
15373 err = dtrace_enabling_replicate(state, match, create);
15374 mutex_exit(&dtrace_lock);
15375
15376 return (err);
15377 }
15378
15379 case DTRACEIOC_PROBEMATCH:
15380 case DTRACEIOC_PROBES: {
15381 dtrace_probe_t *probe = NULL;
15382 dtrace_probedesc_t desc;
15383 dtrace_probekey_t pkey;
15384 dtrace_id_t i;
15385 int m = 0;
15386 uint32_t priv;
15387 uid_t uid;
15388 zoneid_t zoneid;
15389
15390 if (copyin((void *)arg, &desc, sizeof (desc)) != 0)
15391 return (EFAULT);
15392
15393 desc.dtpd_provider[DTRACE_PROVNAMELEN - 1] = '\0';
15394 desc.dtpd_mod[DTRACE_MODNAMELEN - 1] = '\0';
15395 desc.dtpd_func[DTRACE_FUNCNAMELEN - 1] = '\0';
15396 desc.dtpd_name[DTRACE_NAMELEN - 1] = '\0';
15397
15398 /*
15399 * Before we attempt to match this probe, we want to give
15400 * all providers the opportunity to provide it.
15401 */
15402 if (desc.dtpd_id == DTRACE_IDNONE) {
15403 mutex_enter(&dtrace_provider_lock);
15404 dtrace_probe_provide(&desc, NULL);
15405 mutex_exit(&dtrace_provider_lock);
15406 desc.dtpd_id++;
15407 }
15408
15409 if (cmd == DTRACEIOC_PROBEMATCH) {
15410 dtrace_probekey(&desc, &pkey);
15411 pkey.dtpk_id = DTRACE_IDNONE;
15412 }
15413
15414 dtrace_cred2priv(cr, &priv, &uid, &zoneid);
15415
15416 mutex_enter(&dtrace_lock);
15417
15418 if (cmd == DTRACEIOC_PROBEMATCH) {
15419 for (i = desc.dtpd_id; i <= dtrace_nprobes; i++) {
15420 if ((probe = dtrace_probes[i - 1]) != NULL &&
15421 (m = dtrace_match_probe(probe, &pkey,
15422 priv, uid, zoneid)) != 0)
15423 break;
15424 }
15425
15426 if (m < 0) {
15427 mutex_exit(&dtrace_lock);
15428 return (EINVAL);
15429 }
15430
15431 } else {
15432 for (i = desc.dtpd_id; i <= dtrace_nprobes; i++) {
15433 if ((probe = dtrace_probes[i - 1]) != NULL &&
15434 dtrace_match_priv(probe, priv, uid, zoneid))
15435 break;
15436 }
15437 }
15438
15439 if (probe == NULL) {
15440 mutex_exit(&dtrace_lock);
15441 return (ESRCH);
15442 }
15443
15444 dtrace_probe_description(probe, &desc);
15445 mutex_exit(&dtrace_lock);
15446
15447 if (copyout(&desc, (void *)arg, sizeof (desc)) != 0)
15448 return (EFAULT);
15449
15450 return (0);
15451 }
15452
15453 case DTRACEIOC_PROBEARG: {
15454 dtrace_argdesc_t desc;
15455 dtrace_probe_t *probe;
15456 dtrace_provider_t *prov;
15457
15458 if (copyin((void *)arg, &desc, sizeof (desc)) != 0)
15459 return (EFAULT);
15460
15461 if (desc.dtargd_id == DTRACE_IDNONE)
15462 return (EINVAL);
15463
15464 if (desc.dtargd_ndx == DTRACE_ARGNONE)
15465 return (EINVAL);
15466
15467 mutex_enter(&dtrace_provider_lock);
15468 mutex_enter(&mod_lock);
15469 mutex_enter(&dtrace_lock);
15470
15471 if (desc.dtargd_id > dtrace_nprobes) {
15472 mutex_exit(&dtrace_lock);
15473 mutex_exit(&mod_lock);
15474 mutex_exit(&dtrace_provider_lock);
15475 return (EINVAL);
15476 }
15477
15478 if ((probe = dtrace_probes[desc.dtargd_id - 1]) == NULL) {
15479 mutex_exit(&dtrace_lock);
15480 mutex_exit(&mod_lock);
15481 mutex_exit(&dtrace_provider_lock);
15482 return (EINVAL);
15483 }
15484
15485 mutex_exit(&dtrace_lock);
15486
15487 prov = probe->dtpr_provider;
15488
15489 if (prov->dtpv_pops.dtps_getargdesc == NULL) {
15490 /*
15491 * There isn't any typed information for this probe.
15492 * Set the argument number to DTRACE_ARGNONE.
15493 */
15494 desc.dtargd_ndx = DTRACE_ARGNONE;
15495 } else {
15496 desc.dtargd_native[0] = '\0';
15497 desc.dtargd_xlate[0] = '\0';
15498 desc.dtargd_mapping = desc.dtargd_ndx;
15499
15500 prov->dtpv_pops.dtps_getargdesc(prov->dtpv_arg,
15501 probe->dtpr_id, probe->dtpr_arg, &desc);
15502 }
15503
15504 mutex_exit(&mod_lock);
15505 mutex_exit(&dtrace_provider_lock);
15506
15507 if (copyout(&desc, (void *)arg, sizeof (desc)) != 0)
15508 return (EFAULT);
15509
15510 return (0);
15511 }
15512
15513 case DTRACEIOC_GO: {
15514 processorid_t cpuid;
15515 rval = dtrace_state_go(state, &cpuid);
15516
15517 if (rval != 0)
15518 return (rval);
15519
15520 if (copyout(&cpuid, (void *)arg, sizeof (cpuid)) != 0)
15521 return (EFAULT);
15522
15523 return (0);
15524 }
15525
15526 case DTRACEIOC_STOP: {
15527 processorid_t cpuid;
15528
15529 mutex_enter(&dtrace_lock);
15530 rval = dtrace_state_stop(state, &cpuid);
15531 mutex_exit(&dtrace_lock);
15532
15533 if (rval != 0)
15534 return (rval);
15535
15536 if (copyout(&cpuid, (void *)arg, sizeof (cpuid)) != 0)
15537 return (EFAULT);
15538
15539 return (0);
15540 }
15541
15542 case DTRACEIOC_DOFGET: {
15543 dof_hdr_t hdr, *dof;
15544 uint64_t len;
15545
15546 if (copyin((void *)arg, &hdr, sizeof (hdr)) != 0)
15547 return (EFAULT);
15548
15549 mutex_enter(&dtrace_lock);
15550 dof = dtrace_dof_create(state);
15551 mutex_exit(&dtrace_lock);
15552
15553 len = MIN(hdr.dofh_loadsz, dof->dofh_loadsz);
15554 rval = copyout(dof, (void *)arg, len);
15555 dtrace_dof_destroy(dof);
15556
15557 return (rval == 0 ? 0 : EFAULT);
15558 }
15559
15560 case DTRACEIOC_AGGSNAP:
15561 case DTRACEIOC_BUFSNAP: {
15562 dtrace_bufdesc_t desc;
15563 caddr_t cached;
15564 dtrace_buffer_t *buf;
15565
15566 if (copyin((void *)arg, &desc, sizeof (desc)) != 0)
15567 return (EFAULT);
15568
15569 if (desc.dtbd_cpu < 0 || desc.dtbd_cpu >= NCPU)
15570 return (EINVAL);
15571
15572 mutex_enter(&dtrace_lock);
15573
15574 if (cmd == DTRACEIOC_BUFSNAP) {
15575 buf = &state->dts_buffer[desc.dtbd_cpu];
15576 } else {
15577 buf = &state->dts_aggbuffer[desc.dtbd_cpu];
15578 }
15579
15580 if (buf->dtb_flags & (DTRACEBUF_RING | DTRACEBUF_FILL)) {
15581 size_t sz = buf->dtb_offset;
15582
15583 if (state->dts_activity != DTRACE_ACTIVITY_STOPPED) {
15584 mutex_exit(&dtrace_lock);
15585 return (EBUSY);
15586 }
15587
15588 /*
15589 * If this buffer has already been consumed, we're
15590 * going to indicate that there's nothing left here
15591 * to consume.
15592 */
15593 if (buf->dtb_flags & DTRACEBUF_CONSUMED) {
15594 mutex_exit(&dtrace_lock);
15595
15596 desc.dtbd_size = 0;
15597 desc.dtbd_drops = 0;
15598 desc.dtbd_errors = 0;
15599 desc.dtbd_oldest = 0;
15600 sz = sizeof (desc);
15601
15602 if (copyout(&desc, (void *)arg, sz) != 0)
15603 return (EFAULT);
15604
15605 return (0);
15606 }
15607
15608 /*
15609 * If this is a ring buffer that has wrapped, we want
15610 * to copy the whole thing out.
15611 */
15612 if (buf->dtb_flags & DTRACEBUF_WRAPPED) {
15613 dtrace_buffer_polish(buf);
15614 sz = buf->dtb_size;
15615 }
15616
15617 if (copyout(buf->dtb_tomax, desc.dtbd_data, sz) != 0) {
15618 mutex_exit(&dtrace_lock);
15619 return (EFAULT);
15620 }
15621
15622 desc.dtbd_size = sz;
15623 desc.dtbd_drops = buf->dtb_drops;
15624 desc.dtbd_errors = buf->dtb_errors;
15625 desc.dtbd_oldest = buf->dtb_xamot_offset;
15626
15627 mutex_exit(&dtrace_lock);
15628
15629 if (copyout(&desc, (void *)arg, sizeof (desc)) != 0)
15630 return (EFAULT);
15631
15632 buf->dtb_flags |= DTRACEBUF_CONSUMED;
15633
15634 return (0);
15635 }
15636
15637 if (buf->dtb_tomax == NULL) {
15638 ASSERT(buf->dtb_xamot == NULL);
15639 mutex_exit(&dtrace_lock);
15640 return (ENOENT);
15641 }
15642
15643 cached = buf->dtb_tomax;
15644 ASSERT(!(buf->dtb_flags & DTRACEBUF_NOSWITCH));
15645
15646 dtrace_xcall(desc.dtbd_cpu,
15647 (dtrace_xcall_t)dtrace_buffer_switch, buf);
15648
15649 state->dts_errors += buf->dtb_xamot_errors;
15650
15651 /*
15652 * If the buffers did not actually switch, then the cross call
15653 * did not take place -- presumably because the given CPU is
15654 * not in the ready set. If this is the case, we'll return
15655 * ENOENT.
15656 */
15657 if (buf->dtb_tomax == cached) {
15658 ASSERT(buf->dtb_xamot != cached);
15659 mutex_exit(&dtrace_lock);
15660 return (ENOENT);
15661 }
15662
15663 ASSERT(cached == buf->dtb_xamot);
15664
15665 /*
15666 * We have our snapshot; now copy it out.
15667 */
15668 if (copyout(buf->dtb_xamot, desc.dtbd_data,
15669 buf->dtb_xamot_offset) != 0) {
15670 mutex_exit(&dtrace_lock);
15671 return (EFAULT);
15672 }
15673
15674 desc.dtbd_size = buf->dtb_xamot_offset;
15675 desc.dtbd_drops = buf->dtb_xamot_drops;
15676 desc.dtbd_errors = buf->dtb_xamot_errors;
15677 desc.dtbd_oldest = 0;
15678
15679 mutex_exit(&dtrace_lock);
15680
15681 /*
15682 * Finally, copy out the buffer description.
15683 */
15684 if (copyout(&desc, (void *)arg, sizeof (desc)) != 0)
15685 return (EFAULT);
15686
15687 return (0);
15688 }
15689
15690 case DTRACEIOC_CONF: {
15691 dtrace_conf_t conf;
15692
15693 bzero(&conf, sizeof (conf));
15694 conf.dtc_difversion = DIF_VERSION;
15695 conf.dtc_difintregs = DIF_DIR_NREGS;
15696 conf.dtc_diftupregs = DIF_DTR_NREGS;
15697 conf.dtc_ctfmodel = CTF_MODEL_NATIVE;
15698
15699 if (copyout(&conf, (void *)arg, sizeof (conf)) != 0)
15700 return (EFAULT);
15701
15702 return (0);
15703 }
15704
15705 case DTRACEIOC_STATUS: {
15706 dtrace_status_t stat;
15707 dtrace_dstate_t *dstate;
15708 int i, j;
15709 uint64_t nerrs;
15710
15711 /*
15712 * See the comment in dtrace_state_deadman() for the reason
15713 * for setting dts_laststatus to INT64_MAX before setting
15714 * it to the correct value.
15715 */
15716 state->dts_laststatus = INT64_MAX;
15717 dtrace_membar_producer();
15718 state->dts_laststatus = dtrace_gethrtime();
15719
15720 bzero(&stat, sizeof (stat));
15721
15722 mutex_enter(&dtrace_lock);
15723
15724 if (state->dts_activity == DTRACE_ACTIVITY_INACTIVE) {
15725 mutex_exit(&dtrace_lock);
15726 return (ENOENT);
15727 }
15728
15729 if (state->dts_activity == DTRACE_ACTIVITY_DRAINING)
15730 stat.dtst_exiting = 1;
15731
15732 nerrs = state->dts_errors;
15733 dstate = &state->dts_vstate.dtvs_dynvars;
15734
15735 for (i = 0; i < NCPU; i++) {
15736 dtrace_dstate_percpu_t *dcpu = &dstate->dtds_percpu[i];
15737
15738 stat.dtst_dyndrops += dcpu->dtdsc_drops;
15739 stat.dtst_dyndrops_dirty += dcpu->dtdsc_dirty_drops;
15740 stat.dtst_dyndrops_rinsing += dcpu->dtdsc_rinsing_drops;
15741
15742 if (state->dts_buffer[i].dtb_flags & DTRACEBUF_FULL)
15743 stat.dtst_filled++;
15744
15745 nerrs += state->dts_buffer[i].dtb_errors;
15746
15747 for (j = 0; j < state->dts_nspeculations; j++) {
15748 dtrace_speculation_t *spec;
15749 dtrace_buffer_t *buf;
15750
15751 spec = &state->dts_speculations[j];
15752 buf = &spec->dtsp_buffer[i];
15753 stat.dtst_specdrops += buf->dtb_xamot_drops;
15754 }
15755 }
15756
15757 stat.dtst_specdrops_busy = state->dts_speculations_busy;
15758 stat.dtst_specdrops_unavail = state->dts_speculations_unavail;
15759 stat.dtst_stkstroverflows = state->dts_stkstroverflows;
15760 stat.dtst_dblerrors = state->dts_dblerrors;
15761 stat.dtst_killed =
15762 (state->dts_activity == DTRACE_ACTIVITY_KILLED);
15763 stat.dtst_errors = nerrs;
15764
15765 mutex_exit(&dtrace_lock);
15766
15767 if (copyout(&stat, (void *)arg, sizeof (stat)) != 0)
15768 return (EFAULT);
15769
15770 return (0);
15771 }
15772
15773 case DTRACEIOC_FORMAT: {
15774 dtrace_fmtdesc_t fmt;
15775 char *str;
15776 int len;
15777
15778 if (copyin((void *)arg, &fmt, sizeof (fmt)) != 0)
15779 return (EFAULT);
15780
15781 mutex_enter(&dtrace_lock);
15782
15783 if (fmt.dtfd_format == 0 ||
15784 fmt.dtfd_format > state->dts_nformats) {
15785 mutex_exit(&dtrace_lock);
15786 return (EINVAL);
15787 }
15788
15789 /*
15790 * Format strings are allocated contiguously and they are
15791 * never freed; if a format index is less than the number
15792 * of formats, we can assert that the format map is non-NULL
15793 * and that the format for the specified index is non-NULL.
15794 */
15795 ASSERT(state->dts_formats != NULL);
15796 str = state->dts_formats[fmt.dtfd_format - 1];
15797 ASSERT(str != NULL);
15798
15799 len = strlen(str) + 1;
15800
15801 if (len > fmt.dtfd_length) {
15802 fmt.dtfd_length = len;
15803
15804 if (copyout(&fmt, (void *)arg, sizeof (fmt)) != 0) {
15805 mutex_exit(&dtrace_lock);
15806 return (EINVAL);
15807 }
15808 } else {
15809 if (copyout(str, fmt.dtfd_string, len) != 0) {
15810 mutex_exit(&dtrace_lock);
15811 return (EINVAL);
15812 }
15813 }
15814
15815 mutex_exit(&dtrace_lock);
15816 return (0);
15817 }
15818
15819 default:
15820 break;
15821 }
15822
15823 return (ENOTTY);
15824 }
15825
15826 /*ARGSUSED*/
15827 static int
15828 dtrace_detach(dev_info_t *dip, ddi_detach_cmd_t cmd)
15829 {
15830 dtrace_state_t *state;
15831
15832 switch (cmd) {
15833 case DDI_DETACH:
15834 break;
15835
15836 case DDI_SUSPEND:
15837 return (DDI_SUCCESS);
15838
15839 default:
15840 return (DDI_FAILURE);
15841 }
15842
15843 mutex_enter(&cpu_lock);
15844 mutex_enter(&dtrace_provider_lock);
15845 mutex_enter(&dtrace_lock);
15846
15847 ASSERT(dtrace_opens == 0);
15848
15849 if (dtrace_helpers > 0) {
15850 mutex_exit(&dtrace_provider_lock);
15851 mutex_exit(&dtrace_lock);
15852 mutex_exit(&cpu_lock);
15853 return (DDI_FAILURE);
15854 }
15855
15856 if (dtrace_unregister((dtrace_provider_id_t)dtrace_provider) != 0) {
15857 mutex_exit(&dtrace_provider_lock);
15858 mutex_exit(&dtrace_lock);
15859 mutex_exit(&cpu_lock);
15860 return (DDI_FAILURE);
15861 }
15862
15863 dtrace_provider = NULL;
15864
15865 if ((state = dtrace_anon_grab()) != NULL) {
15866 /*
15867 * If there were ECBs on this state, the provider should
15868 * have not been allowed to detach; assert that there is
15869 * none.
15870 */
15871 ASSERT(state->dts_necbs == 0);
15872 dtrace_state_destroy(state);
15873
15874 /*
15875 * If we're being detached with anonymous state, we need to
15876 * indicate to the kernel debugger that DTrace is now inactive.
15877 */
15878 (void) kdi_dtrace_set(KDI_DTSET_DTRACE_DEACTIVATE);
15879 }
15880
15881 bzero(&dtrace_anon, sizeof (dtrace_anon_t));
15882 unregister_cpu_setup_func((cpu_setup_func_t *)dtrace_cpu_setup, NULL);
15883 dtrace_cpu_init = NULL;
15884 dtrace_helpers_cleanup = NULL;
15885 dtrace_helpers_fork = NULL;
15886 dtrace_cpustart_init = NULL;
15887 dtrace_cpustart_fini = NULL;
15888 dtrace_debugger_init = NULL;
15889 dtrace_debugger_fini = NULL;
15890 dtrace_modload = NULL;
15891 dtrace_modunload = NULL;
15892
15893 mutex_exit(&cpu_lock);
15894
15895 if (dtrace_helptrace_enabled) {
15896 kmem_free(dtrace_helptrace_buffer, dtrace_helptrace_bufsize);
15897 dtrace_helptrace_buffer = NULL;
15898 }
15899
15900 kmem_free(dtrace_probes, dtrace_nprobes * sizeof (dtrace_probe_t *));
15901 dtrace_probes = NULL;
15902 dtrace_nprobes = 0;
15903
15904 dtrace_hash_destroy(dtrace_bymod);
15905 dtrace_hash_destroy(dtrace_byfunc);
15906 dtrace_hash_destroy(dtrace_byname);
15907 dtrace_bymod = NULL;
15908 dtrace_byfunc = NULL;
15909 dtrace_byname = NULL;
15910
15911 kmem_cache_destroy(dtrace_state_cache);
15912 vmem_destroy(dtrace_minor);
15913 vmem_destroy(dtrace_arena);
15914
15915 if (dtrace_toxrange != NULL) {
15916 kmem_free(dtrace_toxrange,
15917 dtrace_toxranges_max * sizeof (dtrace_toxrange_t));
15918 dtrace_toxrange = NULL;
15919 dtrace_toxranges = 0;
15920 dtrace_toxranges_max = 0;
15921 }
15922
15923 ddi_remove_minor_node(dtrace_devi, NULL);
15924 dtrace_devi = NULL;
15925
15926 ddi_soft_state_fini(&dtrace_softstate);
15927
15928 ASSERT(dtrace_vtime_references == 0);
15929 ASSERT(dtrace_opens == 0);
15930 ASSERT(dtrace_retained == NULL);
15931
15932 mutex_exit(&dtrace_lock);
15933 mutex_exit(&dtrace_provider_lock);
15934
15935 /*
15936 * We don't destroy the task queue until after we have dropped our
15937 * locks (taskq_destroy() may block on running tasks). To prevent
15938 * attempting to do work after we have effectively detached but before
15939 * the task queue has been destroyed, all tasks dispatched via the
15940 * task queue must check that DTrace is still attached before
15941 * performing any operation.
15942 */
15943 taskq_destroy(dtrace_taskq);
15944 dtrace_taskq = NULL;
15945
15946 return (DDI_SUCCESS);
15947 }
15948
15949 /*ARGSUSED*/
15950 static int
15951 dtrace_info(dev_info_t *dip, ddi_info_cmd_t infocmd, void *arg, void **result)
15952 {
15953 int error;
15954
15955 switch (infocmd) {
15956 case DDI_INFO_DEVT2DEVINFO:
15957 *result = (void *)dtrace_devi;
15958 error = DDI_SUCCESS;
15959 break;
15960 case DDI_INFO_DEVT2INSTANCE:
15961 *result = (void *)0;
15962 error = DDI_SUCCESS;
15963 break;
15964 default:
15965 error = DDI_FAILURE;
15966 }
15967 return (error);
15968 }
15969
15970 static struct cb_ops dtrace_cb_ops = {
15971 dtrace_open, /* open */
15972 dtrace_close, /* close */
15973 nulldev, /* strategy */
15974 nulldev, /* print */
15975 nodev, /* dump */
15976 nodev, /* read */
15977 nodev, /* write */
15978 dtrace_ioctl, /* ioctl */
15979 nodev, /* devmap */
15980 nodev, /* mmap */
15981 nodev, /* segmap */
15982 nochpoll, /* poll */
15983 ddi_prop_op, /* cb_prop_op */
15984 0, /* streamtab */
15985 D_NEW | D_MP /* Driver compatibility flag */
15986 };
15987
15988 static struct dev_ops dtrace_ops = {
15989 DEVO_REV, /* devo_rev */
15990 0, /* refcnt */
15991 dtrace_info, /* get_dev_info */
15992 nulldev, /* identify */
15993 nulldev, /* probe */
15994 dtrace_attach, /* attach */
15995 dtrace_detach, /* detach */
15996 nodev, /* reset */
15997 &dtrace_cb_ops, /* driver operations */
15998 NULL, /* bus operations */
15999 nodev, /* dev power */
16000 ddi_quiesce_not_needed, /* quiesce */
16001 };
16002
16003 static struct modldrv modldrv = {
16004 &mod_driverops, /* module type (this is a pseudo driver) */
16005 "Dynamic Tracing", /* name of module */
16006 &dtrace_ops, /* driver ops */
16007 };
16008
16009 static struct modlinkage modlinkage = {
16010 MODREV_1,
16011 (void *)&modldrv,
16012 NULL
16013 };
16014
16015 int
16016 _init(void)
16017 {
16018 return (mod_install(&modlinkage));
16019 }
16020
16021 int
16022 _info(struct modinfo *modinfop)
16023 {
16024 return (mod_info(&modlinkage, modinfop));
16025 }
16026
16027 int
16028 _fini(void)
16029 {
16030 return (mod_remove(&modlinkage));
16031 }