xref: /titanic_41/usr/src/lib/libdtrace/common/dt_provider.c (revision 8eea8e29cc4374d1ee24c25a07f45af132db3499)
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, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 #include <sys/types.h>
30 #include <sys/sysmacros.h>
31 
32 #include <assert.h>
33 #include <limits.h>
34 #include <strings.h>
35 #include <stdlib.h>
36 #include <alloca.h>
37 #include <unistd.h>
38 #include <errno.h>
39 
40 #include <dt_provider.h>
41 #include <dt_module.h>
42 #include <dt_string.h>
43 #include <dt_list.h>
44 
45 static dt_provider_t *
46 dt_provider_insert(dtrace_hdl_t *dtp, dt_provider_t *pvp, uint_t h)
47 {
48 	dt_list_append(&dtp->dt_provlist, pvp);
49 
50 	pvp->pv_next = dtp->dt_provs[h];
51 	dtp->dt_provs[h] = pvp;
52 	dtp->dt_nprovs++;
53 
54 	return (pvp);
55 }
56 
57 dt_provider_t *
58 dt_provider_lookup(dtrace_hdl_t *dtp, const char *name)
59 {
60 	uint_t h = dt_strtab_hash(name, NULL) % dtp->dt_provbuckets;
61 	dt_provider_t *pvp;
62 
63 	for (pvp = dtp->dt_provs[h]; pvp != NULL; pvp = pvp->pv_next) {
64 		if (strcmp(pvp->pv_desc.dtvd_name, name) == 0)
65 			return (pvp);
66 	}
67 
68 	if (strisglob(name) || name[0] == '\0') {
69 		(void) dt_set_errno(dtp, EDT_NOPROV);
70 		return (NULL);
71 	}
72 
73 	if ((pvp = dt_provider_create(dtp, name)) == NULL)
74 		return (NULL); /* dt_errno is set for us */
75 
76 	if (dt_ioctl(dtp, DTRACEIOC_PROVIDER, &pvp->pv_desc) == -1) {
77 		(void) dt_set_errno(dtp, errno == ESRCH ? EDT_NOPROV : errno);
78 		dt_provider_destroy(dtp, pvp);
79 		return (NULL);
80 	}
81 
82 	pvp->pv_flags |= DT_PROVIDER_IMPL;
83 	return (pvp);
84 }
85 
86 dt_provider_t *
87 dt_provider_create(dtrace_hdl_t *dtp, const char *name)
88 {
89 	dt_provider_t *pvp;
90 
91 	if ((pvp = dt_zalloc(dtp, sizeof (dt_provider_t))) == NULL)
92 		return (NULL);
93 
94 	(void) strlcpy(pvp->pv_desc.dtvd_name, name, DTRACE_PROVNAMELEN);
95 	pvp->pv_probes = dt_idhash_create(pvp->pv_desc.dtvd_name, NULL, 0, 0);
96 	pvp->pv_gen = dtp->dt_gen;
97 	pvp->pv_hdl = dtp;
98 
99 	if (pvp->pv_probes == NULL) {
100 		dt_free(dtp, pvp);
101 		(void) dt_set_errno(dtp, EDT_NOMEM);
102 		return (NULL);
103 	}
104 
105 	pvp->pv_desc.dtvd_attr.dtpa_provider = _dtrace_prvattr;
106 	pvp->pv_desc.dtvd_attr.dtpa_mod = _dtrace_prvattr;
107 	pvp->pv_desc.dtvd_attr.dtpa_func = _dtrace_prvattr;
108 	pvp->pv_desc.dtvd_attr.dtpa_name = _dtrace_prvattr;
109 	pvp->pv_desc.dtvd_attr.dtpa_args = _dtrace_prvattr;
110 
111 	return (dt_provider_insert(dtp, pvp,
112 	    dt_strtab_hash(name, NULL) % dtp->dt_provbuckets));
113 }
114 
115 void
116 dt_provider_destroy(dtrace_hdl_t *dtp, dt_provider_t *pvp)
117 {
118 	dt_provider_t **pp;
119 	uint_t h;
120 
121 	assert(pvp->pv_hdl == dtp);
122 
123 	h = dt_strtab_hash(pvp->pv_desc.dtvd_name, NULL) % dtp->dt_provbuckets;
124 	pp = &dtp->dt_provs[h];
125 
126 	while (*pp != NULL && *pp != pvp)
127 		pp = &(*pp)->pv_next;
128 
129 	assert(*pp != NULL && *pp == pvp);
130 	*pp = pvp->pv_next;
131 
132 	dt_list_delete(&dtp->dt_provlist, pvp);
133 	dtp->dt_nprovs--;
134 
135 	if (pvp->pv_probes != NULL)
136 		dt_idhash_destroy(pvp->pv_probes);
137 
138 	dt_node_link_free(&pvp->pv_nodes);
139 	dt_free(dtp, pvp);
140 }
141 
142 static uint8_t
143 dt_probe_argmap(dt_node_t *xnp, dt_node_t *nnp)
144 {
145 	uint8_t i;
146 
147 	for (i = 0; nnp != NULL; i++) {
148 		if (nnp->dn_string != NULL &&
149 		    strcmp(nnp->dn_string, xnp->dn_string) == 0)
150 			break;
151 		else
152 			nnp = nnp->dn_list;
153 	}
154 
155 	return (i);
156 }
157 
158 static dt_node_t *
159 dt_probe_alloc_args(dt_provider_t *pvp, int argc)
160 {
161 	dt_node_t *args = NULL, *pnp = NULL, *dnp;
162 	int i;
163 
164 	for (i = 0; i < argc; i++, pnp = dnp) {
165 		if ((dnp = dt_node_xalloc(pvp->pv_hdl, DT_NODE_TYPE)) == NULL)
166 			return (NULL);
167 
168 		dnp->dn_link = pvp->pv_nodes;
169 		pvp->pv_nodes = dnp;
170 
171 		if (args == NULL)
172 			args = dnp;
173 		else
174 			pnp->dn_list = dnp;
175 	}
176 
177 	return (args);
178 }
179 
180 static size_t
181 dt_probe_keylen(const dtrace_probedesc_t *pdp)
182 {
183 	return (strlen(pdp->dtpd_mod) + 1 +
184 	    strlen(pdp->dtpd_func) + 1 + strlen(pdp->dtpd_name) + 1);
185 }
186 
187 static char *
188 dt_probe_key(const dtrace_probedesc_t *pdp, char *s)
189 {
190 	(void) snprintf(s, INT_MAX, "%s:%s:%s",
191 	    pdp->dtpd_mod, pdp->dtpd_func, pdp->dtpd_name);
192 	return (s);
193 }
194 
195 /*
196  * If a probe was discovered from the kernel, ask dtrace(7D) for a description
197  * of each of its arguments, including native and translated types.
198  */
199 static dt_probe_t *
200 dt_probe_discover(dt_provider_t *pvp, const dtrace_probedesc_t *pdp)
201 {
202 	dtrace_hdl_t *dtp = pvp->pv_hdl;
203 	char *name = dt_probe_key(pdp, alloca(dt_probe_keylen(pdp)));
204 
205 	dt_node_t *xargs, *nargs;
206 	dt_ident_t *idp;
207 	dt_probe_t *prp;
208 
209 	dtrace_typeinfo_t dtt;
210 	int i, nc, xc;
211 
212 	int adc = _dtrace_argmax;
213 	dtrace_argdesc_t *adv = alloca(sizeof (dtrace_argdesc_t) * adc);
214 	dtrace_argdesc_t *adp = adv;
215 
216 	assert(strcmp(pvp->pv_desc.dtvd_name, pdp->dtpd_provider) == 0);
217 	assert(pdp->dtpd_id != DTRACE_IDNONE);
218 
219 	dt_dprintf("discovering probe %s:%s id=%d\n",
220 	    pvp->pv_desc.dtvd_name, name, pdp->dtpd_id);
221 
222 	for (nc = -1, i = 0; i < adc; i++, adp++) {
223 		bzero(adp, sizeof (dtrace_argdesc_t));
224 		adp->dtargd_ndx = i;
225 		adp->dtargd_id = pdp->dtpd_id;
226 
227 		if (dt_ioctl(dtp, DTRACEIOC_PROBEARG, adp) != 0) {
228 			(void) dt_set_errno(dtp, errno);
229 			return (NULL);
230 		}
231 
232 		if (adp->dtargd_ndx == DTRACE_ARGNONE)
233 			break; /* all argument descs have been retrieved */
234 
235 		nc = MAX(nc, adp->dtargd_mapping);
236 	}
237 
238 	xc = i;
239 	nc++;
240 
241 	/*
242 	 * Now that we have discovered the number of native and translated
243 	 * arguments from the argument descriptions, allocate a new probe ident
244 	 * and corresponding dt_probe_t and hash it into the provider.
245 	 */
246 	xargs = dt_probe_alloc_args(pvp, xc);
247 	nargs = dt_probe_alloc_args(pvp, nc);
248 
249 	if ((xc != 0 && xargs == NULL) || (nc != 0 && nargs == NULL))
250 		return (NULL); /* dt_errno is set for us */
251 
252 	idp = dt_ident_create(name, DT_IDENT_PROBE,
253 	    DT_IDFLG_ORPHAN, pdp->dtpd_id, _dtrace_defattr, 0,
254 	    &dt_idops_probe, NULL, dtp->dt_gen);
255 
256 	if (idp == NULL) {
257 		(void) dt_set_errno(dtp, EDT_NOMEM);
258 		return (NULL);
259 	}
260 
261 	if ((prp = dt_probe_create(dtp, idp, nargs, nc, xargs, xc)) == NULL) {
262 		dt_ident_destroy(idp);
263 		return (NULL);
264 	}
265 
266 	dt_probe_declare(pvp, prp);
267 
268 	/*
269 	 * Once our new dt_probe_t is fully constructed, iterate over the
270 	 * cached argument descriptions and assign types to prp->pr_nargv[]
271 	 * and prp->pr_xargv[] and assign mappings to prp->pr_mapping[].
272 	 */
273 	for (adp = adv, i = 0; i < xc; i++, adp++) {
274 		if (dtrace_type_strcompile(dtp,
275 		    adp->dtargd_native, &dtt) != 0) {
276 			dt_dprintf("failed to resolve input type %s "
277 			    "for %s:%s arg #%d: %s\n", adp->dtargd_native,
278 			    pvp->pv_desc.dtvd_name, name, i + 1,
279 			    dtrace_errmsg(dtp, dtrace_errno(dtp)));
280 
281 			dtt.dtt_object = NULL;
282 			dtt.dtt_ctfp = NULL;
283 			dtt.dtt_type = CTF_ERR;
284 		} else {
285 			dt_node_type_assign(prp->pr_nargv[adp->dtargd_mapping],
286 			    dtt.dtt_ctfp, dtt.dtt_type);
287 		}
288 
289 		if (dtt.dtt_type != CTF_ERR && (adp->dtargd_xlate[0] == '\0' ||
290 		    strcmp(adp->dtargd_native, adp->dtargd_xlate) == 0)) {
291 			dt_node_type_propagate(prp->pr_nargv[
292 			    adp->dtargd_mapping], prp->pr_xargv[i]);
293 		} else if (dtrace_type_strcompile(dtp,
294 		    adp->dtargd_xlate, &dtt) != 0) {
295 			dt_dprintf("failed to resolve output type %s "
296 			    "for %s:%s arg #%d: %s\n", adp->dtargd_xlate,
297 			    pvp->pv_desc.dtvd_name, name, i + 1,
298 			    dtrace_errmsg(dtp, dtrace_errno(dtp)));
299 
300 			dtt.dtt_object = NULL;
301 			dtt.dtt_ctfp = NULL;
302 			dtt.dtt_type = CTF_ERR;
303 		} else {
304 			dt_node_type_assign(prp->pr_xargv[i],
305 			    dtt.dtt_ctfp, dtt.dtt_type);
306 		}
307 
308 		prp->pr_mapping[i] = adp->dtargd_mapping;
309 		prp->pr_argv[i] = dtt;
310 	}
311 
312 	return (prp);
313 }
314 
315 /*
316  * Lookup a probe declaration based on a known provider and full or partially
317  * specified module, function, and name.  If the probe is not known to us yet,
318  * ask dtrace(7D) to match the description and then cache any useful results.
319  */
320 dt_probe_t *
321 dt_probe_lookup(dt_provider_t *pvp, const char *s)
322 {
323 	dtrace_hdl_t *dtp = pvp->pv_hdl;
324 	dtrace_probedesc_t pd;
325 	dt_ident_t *idp;
326 	size_t keylen;
327 	char *key;
328 
329 	if (dtrace_str2desc(dtp, DTRACE_PROBESPEC_NAME, s, &pd) != 0)
330 		return (NULL); /* dt_errno is set for us */
331 
332 	keylen = dt_probe_keylen(&pd);
333 	key = dt_probe_key(&pd, alloca(keylen));
334 
335 	/*
336 	 * If the probe is already declared, then return the dt_probe_t from
337 	 * the existing identifier.  This could come from a static declaration
338 	 * or it could have been cached from an earlier call to this function.
339 	 */
340 	if ((idp = dt_idhash_lookup(pvp->pv_probes, key)) != NULL)
341 		return (idp->di_data);
342 
343 	/*
344 	 * If the probe isn't known, use the probe description computed above
345 	 * to ask dtrace(7D) to find the first matching probe.
346 	 */
347 	if (dt_ioctl(dtp, DTRACEIOC_PROBEMATCH, &pd) == 0)
348 		return (dt_probe_discover(pvp, &pd));
349 
350 	if (errno == ESRCH || errno == EBADF)
351 		(void) dt_set_errno(dtp, EDT_NOPROBE);
352 	else
353 		(void) dt_set_errno(dtp, errno);
354 
355 	return (NULL);
356 }
357 
358 dt_probe_t *
359 dt_probe_create(dtrace_hdl_t *dtp, dt_ident_t *idp,
360     dt_node_t *nargs, uint_t nargc, dt_node_t *xargs, uint_t xargc)
361 {
362 	dt_module_t *dmp;
363 	dt_probe_t *prp;
364 	const char *p;
365 	uint_t i;
366 
367 	assert(idp->di_kind == DT_IDENT_PROBE);
368 	assert(idp->di_data == NULL);
369 
370 	if (xargs == NULL) {
371 		xargs = nargs;
372 		xargc = nargc;
373 	}
374 
375 	if ((prp = dt_alloc(dtp, sizeof (dt_probe_t))) == NULL)
376 		return (NULL);
377 
378 	prp->pr_pvp = NULL;
379 	prp->pr_ident = idp;
380 
381 	p = strrchr(idp->di_name, ':');
382 	assert(p != NULL);
383 	prp->pr_name = p + 1;
384 
385 	prp->pr_nargs = nargs;
386 	prp->pr_nargv = dt_alloc(dtp, sizeof (dt_node_t *) * nargc);
387 	prp->pr_nargc = nargc;
388 	prp->pr_xargs = xargs;
389 	prp->pr_xargv = dt_alloc(dtp, sizeof (dt_node_t *) * xargc);
390 	prp->pr_xargc = xargc;
391 	prp->pr_mapping = dt_alloc(dtp, sizeof (uint8_t) * xargc);
392 	prp->pr_inst = NULL;
393 	prp->pr_argv = dt_alloc(dtp, sizeof (dtrace_typeinfo_t) * xargc);
394 	prp->pr_argc = xargc;
395 
396 	if ((prp->pr_nargc != 0 && prp->pr_nargv == NULL) ||
397 	    (prp->pr_xargc != 0 && prp->pr_xargv == NULL) ||
398 	    (prp->pr_xargc != 0 && prp->pr_mapping == NULL) ||
399 	    (prp->pr_argc != 0 && prp->pr_argv == NULL)) {
400 		dt_probe_destroy(prp);
401 		return (NULL);
402 	}
403 
404 	for (i = 0; i < xargc; i++, xargs = xargs->dn_list) {
405 		if (xargs->dn_string != NULL)
406 			prp->pr_mapping[i] = dt_probe_argmap(xargs, nargs);
407 		else
408 			prp->pr_mapping[i] = i;
409 
410 		prp->pr_xargv[i] = xargs;
411 
412 		if ((dmp = dt_module_lookup_by_ctf(dtp,
413 		    xargs->dn_ctfp)) != NULL)
414 			prp->pr_argv[i].dtt_object = dmp->dm_name;
415 		else
416 			prp->pr_argv[i].dtt_object = NULL;
417 
418 		prp->pr_argv[i].dtt_ctfp = xargs->dn_ctfp;
419 		prp->pr_argv[i].dtt_type = xargs->dn_type;
420 	}
421 
422 	for (i = 0; i < nargc; i++, nargs = nargs->dn_list)
423 		prp->pr_nargv[i] = nargs;
424 
425 	idp->di_data = prp;
426 	return (prp);
427 }
428 
429 void
430 dt_probe_declare(dt_provider_t *pvp, dt_probe_t *prp)
431 {
432 	assert(prp->pr_ident->di_kind == DT_IDENT_PROBE);
433 	assert(prp->pr_ident->di_data == prp);
434 	assert(prp->pr_pvp == NULL);
435 
436 	if (prp->pr_xargs != prp->pr_nargs)
437 		pvp->pv_flags &= ~DT_PROVIDER_INTF;
438 
439 	prp->pr_pvp = pvp;
440 	dt_idhash_xinsert(pvp->pv_probes, prp->pr_ident);
441 }
442 
443 void
444 dt_probe_destroy(dt_probe_t *prp)
445 {
446 	dt_probe_instance_t *pip, *pip_next;
447 	dtrace_hdl_t *dtp;
448 
449 	if (prp->pr_pvp != NULL)
450 		dtp = prp->pr_pvp->pv_hdl;
451 	else
452 		dtp = yypcb->pcb_hdl;
453 
454 	dt_node_list_free(&prp->pr_nargs);
455 	dt_node_list_free(&prp->pr_xargs);
456 
457 	dt_free(dtp, prp->pr_nargv);
458 	dt_free(dtp, prp->pr_xargv);
459 
460 	for (pip = prp->pr_inst; pip != NULL; pip = pip_next) {
461 		pip_next = pip->pi_next;
462 		dt_free(dtp, pip->pi_offs);
463 		dt_free(dtp, pip);
464 	}
465 
466 	dt_free(dtp, prp->pr_mapping);
467 	dt_free(dtp, prp->pr_argv);
468 	dt_free(dtp, prp);
469 }
470 
471 int
472 dt_probe_define(dt_provider_t *pvp, dt_probe_t *prp,
473     const char *fname, uint32_t offset)
474 {
475 	dtrace_hdl_t *dtp = pvp->pv_hdl;
476 	dt_probe_instance_t *pip;
477 
478 	for (pip = prp->pr_inst; pip != NULL; pip = pip->pi_next) {
479 		if (strcmp(pip->pi_fname, fname) == 0)
480 			break;
481 	}
482 
483 	if (pip == NULL) {
484 		if ((pip = dt_alloc(dtp, sizeof (*pip))) == NULL ||
485 		    (pip->pi_offs = dt_alloc(dtp, sizeof (uint32_t))) == NULL) {
486 			dt_free(dtp, pip);
487 			return (-1);
488 		}
489 
490 		(void) strlcpy(pip->pi_fname, fname, sizeof (pip->pi_fname));
491 		pip->pi_noffs = 0;
492 		pip->pi_maxoffs = 1;
493 		pip->pi_next = prp->pr_inst;
494 
495 		prp->pr_inst = pip;
496 	}
497 
498 	if (pip->pi_noffs == pip->pi_maxoffs) {
499 		uint_t new_max = pip->pi_maxoffs * 2;
500 		uint32_t *new_offs = dt_alloc(dtp, sizeof (uint32_t) * new_max);
501 
502 		if (new_offs == NULL)
503 			return (-1);
504 
505 		bcopy(pip->pi_offs, new_offs,
506 		    sizeof (uint32_t) * pip->pi_maxoffs);
507 
508 		dt_free(dtp, pip->pi_offs);
509 		pip->pi_maxoffs = new_max;
510 		pip->pi_offs = new_offs;
511 	}
512 
513 	dt_dprintf("defined probe %s:%s %s() +0x%x\n",
514 	    pvp->pv_desc.dtvd_name, prp->pr_ident->di_name, fname, offset);
515 
516 	assert(pip->pi_noffs < pip->pi_maxoffs);
517 	pip->pi_offs[pip->pi_noffs++] = offset;
518 
519 	return (0);
520 }
521 
522 /*ARGSUSED*/
523 static int
524 dt_probe_desc(dtrace_hdl_t *dtp, const dtrace_probedesc_t *pdp, void *arg)
525 {
526 	if (((dtrace_probedesc_t *)arg)->dtpd_id == DTRACE_IDNONE) {
527 		bcopy(pdp, arg, sizeof (dtrace_probedesc_t));
528 		return (0);
529 	}
530 
531 	return (1);
532 }
533 
534 dt_probe_t *
535 dt_probe_info(dtrace_hdl_t *dtp,
536     const dtrace_probedesc_t *pdp, dtrace_probeinfo_t *pip)
537 {
538 	int m_is_glob = pdp->dtpd_mod[0] == '\0' || strisglob(pdp->dtpd_mod);
539 	int f_is_glob = pdp->dtpd_func[0] == '\0' || strisglob(pdp->dtpd_func);
540 	int n_is_glob = pdp->dtpd_name[0] == '\0' || strisglob(pdp->dtpd_name);
541 
542 	dt_probe_t *prp = NULL;
543 	const dtrace_pattr_t *pap;
544 	dt_provider_t *pvp;
545 	dt_ident_t *idp;
546 
547 	/*
548 	 * Attempt to lookup the probe in our existing cache for this provider.
549 	 * If none is found and an explicit probe ID was specified, discover
550 	 * that specific probe and cache its description and arguments.
551 	 */
552 	if ((pvp = dt_provider_lookup(dtp, pdp->dtpd_provider)) != NULL) {
553 		size_t keylen = dt_probe_keylen(pdp);
554 		char *key = dt_probe_key(pdp, alloca(keylen));
555 
556 		if ((idp = dt_idhash_lookup(pvp->pv_probes, key)) != NULL)
557 			prp = idp->di_data;
558 		else if (pdp->dtpd_id != DTRACE_IDNONE)
559 			prp = dt_probe_discover(pvp, pdp);
560 	}
561 
562 	/*
563 	 * If no probe was found in our cache, convert the caller's partial
564 	 * probe description into a fully-formed matching probe description by
565 	 * iterating over up to at most two probes that match 'pdp'.  We then
566 	 * call dt_probe_discover() on the resulting probe identifier.
567 	 */
568 	if (prp == NULL) {
569 		dtrace_probedesc_t pd;
570 		int m;
571 
572 		bzero(&pd, sizeof (pd));
573 		pd.dtpd_id = DTRACE_IDNONE;
574 
575 		/*
576 		 * Call dtrace_probe_iter() to find matching probes.  Our
577 		 * dt_probe_desc() callback will produce the following results:
578 		 *
579 		 * m < 0 dtrace_probe_iter() found zero matches (or failed).
580 		 * m > 0 dtrace_probe_iter() found more than one match.
581 		 * m = 0 dtrace_probe_iter() found exactly one match.
582 		 */
583 		if ((m = dtrace_probe_iter(dtp, pdp, dt_probe_desc, &pd)) < 0)
584 			return (NULL); /* dt_errno is set for us */
585 
586 		if ((pvp = dt_provider_lookup(dtp, pd.dtpd_provider)) == NULL)
587 			return (NULL); /* dt_errno is set for us */
588 
589 		/*
590 		 * If more than one probe was matched, then do not report probe
591 		 * information if either of the following conditions is true:
592 		 *
593 		 * (a) The Arguments Data stability of the matched provider is
594 		 *	less than Evolving.
595 		 *
596 		 * (b) Any description component that is at least Evolving is
597 		 *	empty or is specified using a globbing expression.
598 		 *
599 		 * These conditions imply that providers that provide Evolving
600 		 * or better Arguments Data stability must guarantee that all
601 		 * probes with identical field names in a field of Evolving or
602 		 * better Name stability have identical argument signatures.
603 		 */
604 		if (m > 0) {
605 			if (pvp->pv_desc.dtvd_attr.dtpa_args.dtat_data <
606 			    DTRACE_STABILITY_EVOLVING) {
607 				(void) dt_set_errno(dtp, EDT_UNSTABLE);
608 				return (NULL);
609 			}
610 
611 
612 			if (pvp->pv_desc.dtvd_attr.dtpa_mod.dtat_name >=
613 			    DTRACE_STABILITY_EVOLVING && m_is_glob) {
614 				(void) dt_set_errno(dtp, EDT_UNSTABLE);
615 				return (NULL);
616 			}
617 
618 			if (pvp->pv_desc.dtvd_attr.dtpa_func.dtat_name >=
619 			    DTRACE_STABILITY_EVOLVING && f_is_glob) {
620 				(void) dt_set_errno(dtp, EDT_UNSTABLE);
621 				return (NULL);
622 			}
623 
624 			if (pvp->pv_desc.dtvd_attr.dtpa_name.dtat_name >=
625 			    DTRACE_STABILITY_EVOLVING && n_is_glob) {
626 				(void) dt_set_errno(dtp, EDT_UNSTABLE);
627 				return (NULL);
628 			}
629 		}
630 
631 		if ((prp = dt_probe_discover(pvp, &pd)) == NULL)
632 			return (NULL); /* dt_errno is set for us */
633 	}
634 
635 	assert(pvp != NULL && prp != NULL);
636 
637 	/*
638 	 * Compute the probe description attributes by taking the minimum of
639 	 * the attributes of the specified fields.  If no provider is specified
640 	 * or a glob pattern is used for the provider, use Unstable attributes.
641 	 */
642 	if (pdp->dtpd_provider[0] == '\0' || strisglob(pdp->dtpd_provider))
643 		pap = &_dtrace_prvdesc;
644 	else
645 		pap = &pvp->pv_desc.dtvd_attr;
646 
647 	pip->dtp_attr = pap->dtpa_provider;
648 
649 	if (!m_is_glob)
650 		pip->dtp_attr = dt_attr_min(pip->dtp_attr, pap->dtpa_mod);
651 	if (!f_is_glob)
652 		pip->dtp_attr = dt_attr_min(pip->dtp_attr, pap->dtpa_func);
653 	if (!n_is_glob)
654 		pip->dtp_attr = dt_attr_min(pip->dtp_attr, pap->dtpa_name);
655 
656 	pip->dtp_arga = pap->dtpa_args;
657 	pip->dtp_argv = prp->pr_argv;
658 	pip->dtp_argc = prp->pr_argc;
659 
660 	return (prp);
661 }
662 
663 int
664 dtrace_probe_info(dtrace_hdl_t *dtp,
665     const dtrace_probedesc_t *pdp, dtrace_probeinfo_t *pip)
666 {
667 	return (dt_probe_info(dtp, pdp, pip) != NULL ? 0 : -1);
668 }
669 
670 /*ARGSUSED*/
671 static int
672 dt_probe_iter(dt_idhash_t *ihp, dt_ident_t *idp, dt_probe_iter_t *pit)
673 {
674 	const dt_probe_t *prp = idp->di_data;
675 
676 	if (!dt_gmatch(prp->pr_name, pit->pit_pat))
677 		return (0); /* continue on and examine next probe in hash */
678 
679 	(void) strlcpy(pit->pit_desc.dtpd_name, prp->pr_name, DTRACE_NAMELEN);
680 	pit->pit_desc.dtpd_id = idp->di_id;
681 	pit->pit_matches++;
682 
683 	return (pit->pit_func(pit->pit_hdl, &pit->pit_desc, pit->pit_arg));
684 }
685 
686 int
687 dtrace_probe_iter(dtrace_hdl_t *dtp,
688     const dtrace_probedesc_t *pdp, dtrace_probe_f *func, void *arg)
689 {
690 	const char *provider = pdp ? pdp->dtpd_provider : NULL;
691 	dtrace_id_t id = DTRACE_IDNONE;
692 
693 	dtrace_probedesc_t pd;
694 	dt_probe_iter_t pit;
695 	int cmd, rv;
696 
697 	bzero(&pit, sizeof (pit));
698 	pit.pit_hdl = dtp;
699 	pit.pit_func = func;
700 	pit.pit_arg = arg;
701 	pit.pit_pat = pdp ? pdp->dtpd_name : NULL;
702 
703 	for (pit.pit_pvp = dt_list_next(&dtp->dt_provlist);
704 	    pit.pit_pvp != NULL; pit.pit_pvp = dt_list_next(pit.pit_pvp)) {
705 
706 		if (pit.pit_pvp->pv_flags & DT_PROVIDER_IMPL)
707 			continue; /* we'll get these later using dt_ioctl() */
708 
709 		if (!dt_gmatch(pit.pit_pvp->pv_desc.dtvd_name, provider))
710 			continue;
711 
712 		(void) strlcpy(pit.pit_desc.dtpd_provider,
713 		    pit.pit_pvp->pv_desc.dtvd_name, DTRACE_PROVNAMELEN);
714 
715 		if ((rv = dt_idhash_iter(pit.pit_pvp->pv_probes,
716 		    (dt_idhash_f *)dt_probe_iter, &pit)) != 0)
717 			return (rv);
718 	}
719 
720 	if (pdp != NULL)
721 		cmd = DTRACEIOC_PROBEMATCH;
722 	else
723 		cmd = DTRACEIOC_PROBES;
724 
725 	for (;;) {
726 		if (pdp != NULL)
727 			bcopy(pdp, &pd, sizeof (pd));
728 
729 		pd.dtpd_id = id;
730 
731 		if (dt_ioctl(dtp, cmd, &pd) != 0)
732 			break;
733 		else if ((rv = func(dtp, &pd, arg)) != 0)
734 			return (rv);
735 
736 		pit.pit_matches++;
737 		id = pd.dtpd_id + 1;
738 	}
739 
740 	switch (errno) {
741 	case ESRCH:
742 	case EBADF:
743 		return (pit.pit_matches ? 0 : dt_set_errno(dtp, EDT_NOPROBE));
744 	case EINVAL:
745 		return (dt_set_errno(dtp, EDT_BADPGLOB));
746 	default:
747 		return (dt_set_errno(dtp, errno));
748 	}
749 }
750