xref: /freebsd/sys/cddl/dev/dtrace/dtrace_ioctl.c (revision 907b59d76938e654f0d040a888e8dfca3de1e222)
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  * $FreeBSD$
22  *
23  */
24 
25 static int dtrace_verbose_ioctl;
26 SYSCTL_INT(_debug_dtrace, OID_AUTO, verbose_ioctl, CTLFLAG_RW,
27     &dtrace_verbose_ioctl, 0, "log DTrace ioctls");
28 
29 #define DTRACE_IOCTL_PRINTF(fmt, ...)	if (dtrace_verbose_ioctl) printf(fmt, ## __VA_ARGS__ )
30 
31 static int
32 dtrace_ioctl_helper(struct cdev *dev, u_long cmd, caddr_t addr, int flags,
33     struct thread *td)
34 {
35 	struct proc *p;
36 	dof_helper_t *dhp;
37 	dof_hdr_t *dof;
38 	int rval;
39 
40 	dhp = NULL;
41 	dof = NULL;
42 	rval = 0;
43 	switch (cmd) {
44 	case DTRACEHIOC_ADDDOF:
45 		dhp = (dof_helper_t *)addr;
46 		addr = (caddr_t)(uintptr_t)dhp->dofhp_dof;
47 		/* FALLTHROUGH */
48 	case DTRACEHIOC_ADD:
49 		p = curproc;
50 		if (dhp == NULL || p->p_pid == dhp->dofhp_pid) {
51 			dof = dtrace_dof_copyin((uintptr_t)addr, &rval);
52 		} else {
53 			p = pfind(dhp->dofhp_pid);
54 			if (p == NULL)
55 				return (EINVAL);
56 			if (!P_SHOULDSTOP(p) ||
57 			    (p->p_flag & (P_TRACED | P_WEXIT)) != P_TRACED ||
58 			    p->p_pptr != curproc) {
59 				PROC_UNLOCK(p);
60 				return (EINVAL);
61 			}
62 			_PHOLD(p);
63 			PROC_UNLOCK(p);
64 			dof = dtrace_dof_copyin_proc(p, (uintptr_t)addr, &rval);
65 		}
66 
67 		if (dof == NULL) {
68 			if (p != curproc)
69 				PRELE(p);
70 			break;
71 		}
72 
73 		mutex_enter(&dtrace_lock);
74 		if ((rval = dtrace_helper_slurp(dof, dhp, p)) != -1) {
75 			if (dhp != NULL) {
76 				dhp->dofhp_gen = rval;
77 				copyout(dhp, addr, sizeof(*dhp));
78 			}
79 			rval = 0;
80 		} else {
81 			rval = EINVAL;
82 		}
83 		mutex_exit(&dtrace_lock);
84 		if (p != curproc)
85 			PRELE(p);
86 		break;
87 	case DTRACEHIOC_REMOVE:
88 		mutex_enter(&dtrace_lock);
89 		rval = dtrace_helper_destroygen(NULL, *(int *)(uintptr_t)addr);
90 		mutex_exit(&dtrace_lock);
91 		break;
92 	default:
93 		rval = ENOTTY;
94 		break;
95 	}
96 	return (rval);
97 }
98 
99 /* ARGSUSED */
100 static int
101 dtrace_ioctl(struct cdev *dev, u_long cmd, caddr_t addr,
102     int flags __unused, struct thread *td)
103 {
104 	dtrace_state_t *state;
105 	devfs_get_cdevpriv((void **) &state);
106 
107 	int error = 0;
108 	if (state == NULL)
109 		return (EINVAL);
110 
111 	if (state->dts_anon) {
112 		ASSERT(dtrace_anon.dta_state == NULL);
113 		state = state->dts_anon;
114 	}
115 
116 	switch (cmd) {
117 	case DTRACEIOC_AGGDESC: {
118 		dtrace_aggdesc_t **paggdesc = (dtrace_aggdesc_t **) addr;
119 		dtrace_aggdesc_t aggdesc;
120 		dtrace_action_t *act;
121 		dtrace_aggregation_t *agg;
122 		int nrecs;
123 		uint32_t offs;
124 		dtrace_recdesc_t *lrec;
125 		void *buf;
126 		size_t size;
127 		uintptr_t dest;
128 
129 		DTRACE_IOCTL_PRINTF("%s(%d): DTRACEIOC_AGGDESC\n",__func__,__LINE__);
130 
131 		if (copyin((void *) *paggdesc, &aggdesc, sizeof (aggdesc)) != 0)
132 			return (EFAULT);
133 
134 		mutex_enter(&dtrace_lock);
135 
136 		if ((agg = dtrace_aggid2agg(state, aggdesc.dtagd_id)) == NULL) {
137 			mutex_exit(&dtrace_lock);
138 			return (EINVAL);
139 		}
140 
141 		aggdesc.dtagd_epid = agg->dtag_ecb->dte_epid;
142 
143 		nrecs = aggdesc.dtagd_nrecs;
144 		aggdesc.dtagd_nrecs = 0;
145 
146 		offs = agg->dtag_base;
147 		lrec = &agg->dtag_action.dta_rec;
148 		aggdesc.dtagd_size = lrec->dtrd_offset + lrec->dtrd_size - offs;
149 
150 		for (act = agg->dtag_first; ; act = act->dta_next) {
151 			ASSERT(act->dta_intuple ||
152 			    DTRACEACT_ISAGG(act->dta_kind));
153 
154 			/*
155 			 * If this action has a record size of zero, it
156 			 * denotes an argument to the aggregating action.
157 			 * Because the presence of this record doesn't (or
158 			 * shouldn't) affect the way the data is interpreted,
159 			 * we don't copy it out to save user-level the
160 			 * confusion of dealing with a zero-length record.
161 			 */
162 			if (act->dta_rec.dtrd_size == 0) {
163 				ASSERT(agg->dtag_hasarg);
164 				continue;
165 			}
166 
167 			aggdesc.dtagd_nrecs++;
168 
169 			if (act == &agg->dtag_action)
170 				break;
171 		}
172 
173 		/*
174 		 * Now that we have the size, we need to allocate a temporary
175 		 * buffer in which to store the complete description.  We need
176 		 * the temporary buffer to be able to drop dtrace_lock()
177 		 * across the copyout(), below.
178 		 */
179 		size = sizeof (dtrace_aggdesc_t) +
180 		    (aggdesc.dtagd_nrecs * sizeof (dtrace_recdesc_t));
181 
182 		buf = kmem_alloc(size, KM_SLEEP);
183 		dest = (uintptr_t)buf;
184 
185 		bcopy(&aggdesc, (void *)dest, sizeof (aggdesc));
186 		dest += offsetof(dtrace_aggdesc_t, dtagd_rec[0]);
187 
188 		for (act = agg->dtag_first; ; act = act->dta_next) {
189 			dtrace_recdesc_t rec = act->dta_rec;
190 
191 			/*
192 			 * See the comment in the above loop for why we pass
193 			 * over zero-length records.
194 			 */
195 			if (rec.dtrd_size == 0) {
196 				ASSERT(agg->dtag_hasarg);
197 				continue;
198 			}
199 
200 			if (nrecs-- == 0)
201 				break;
202 
203 			rec.dtrd_offset -= offs;
204 			bcopy(&rec, (void *)dest, sizeof (rec));
205 			dest += sizeof (dtrace_recdesc_t);
206 
207 			if (act == &agg->dtag_action)
208 				break;
209 		}
210 
211 		mutex_exit(&dtrace_lock);
212 
213 		if (copyout(buf, (void *) *paggdesc, dest - (uintptr_t)buf) != 0) {
214 			kmem_free(buf, size);
215 			return (EFAULT);
216 		}
217 
218 		kmem_free(buf, size);
219 		return (0);
220 	}
221 	case DTRACEIOC_AGGSNAP:
222 	case DTRACEIOC_BUFSNAP: {
223 		dtrace_bufdesc_t **pdesc = (dtrace_bufdesc_t **) addr;
224 		dtrace_bufdesc_t desc;
225 		caddr_t cached;
226 		dtrace_buffer_t *buf;
227 
228 		dtrace_debug_output();
229 
230 		if (copyin((void *) *pdesc, &desc, sizeof (desc)) != 0)
231 			return (EFAULT);
232 
233 		DTRACE_IOCTL_PRINTF("%s(%d): %s curcpu %d cpu %d\n",
234 		    __func__,__LINE__,
235 		    cmd == DTRACEIOC_AGGSNAP ?
236 		    "DTRACEIOC_AGGSNAP":"DTRACEIOC_BUFSNAP",
237 		    curcpu, desc.dtbd_cpu);
238 
239 		if (desc.dtbd_cpu >= NCPU)
240 			return (ENOENT);
241 		if (pcpu_find(desc.dtbd_cpu) == NULL)
242 			return (ENOENT);
243 
244 		mutex_enter(&dtrace_lock);
245 
246 		if (cmd == DTRACEIOC_BUFSNAP) {
247 			buf = &state->dts_buffer[desc.dtbd_cpu];
248 		} else {
249 			buf = &state->dts_aggbuffer[desc.dtbd_cpu];
250 		}
251 
252 		if (buf->dtb_flags & (DTRACEBUF_RING | DTRACEBUF_FILL)) {
253 			size_t sz = buf->dtb_offset;
254 
255 			if (state->dts_activity != DTRACE_ACTIVITY_STOPPED) {
256 				mutex_exit(&dtrace_lock);
257 				return (EBUSY);
258 			}
259 
260 			/*
261 			 * If this buffer has already been consumed, we're
262 			 * going to indicate that there's nothing left here
263 			 * to consume.
264 			 */
265 			if (buf->dtb_flags & DTRACEBUF_CONSUMED) {
266 				mutex_exit(&dtrace_lock);
267 
268 				desc.dtbd_size = 0;
269 				desc.dtbd_drops = 0;
270 				desc.dtbd_errors = 0;
271 				desc.dtbd_oldest = 0;
272 				sz = sizeof (desc);
273 
274 				if (copyout(&desc, (void *) *pdesc, sz) != 0)
275 					return (EFAULT);
276 
277 				return (0);
278 			}
279 
280 			/*
281 			 * If this is a ring buffer that has wrapped, we want
282 			 * to copy the whole thing out.
283 			 */
284 			if (buf->dtb_flags & DTRACEBUF_WRAPPED) {
285 				dtrace_buffer_polish(buf);
286 				sz = buf->dtb_size;
287 			}
288 
289 			if (copyout(buf->dtb_tomax, desc.dtbd_data, sz) != 0) {
290 				mutex_exit(&dtrace_lock);
291 				return (EFAULT);
292 			}
293 
294 			desc.dtbd_size = sz;
295 			desc.dtbd_drops = buf->dtb_drops;
296 			desc.dtbd_errors = buf->dtb_errors;
297 			desc.dtbd_oldest = buf->dtb_xamot_offset;
298 			desc.dtbd_timestamp = dtrace_gethrtime();
299 
300 			mutex_exit(&dtrace_lock);
301 
302 			if (copyout(&desc, (void *) *pdesc, sizeof (desc)) != 0)
303 				return (EFAULT);
304 
305 			buf->dtb_flags |= DTRACEBUF_CONSUMED;
306 
307 			return (0);
308 		}
309 
310 		if (buf->dtb_tomax == NULL) {
311 			ASSERT(buf->dtb_xamot == NULL);
312 			mutex_exit(&dtrace_lock);
313 			return (ENOENT);
314 		}
315 
316 		cached = buf->dtb_tomax;
317 		ASSERT(!(buf->dtb_flags & DTRACEBUF_NOSWITCH));
318 
319 		dtrace_xcall(desc.dtbd_cpu,
320 		    (dtrace_xcall_t)dtrace_buffer_switch, buf);
321 
322 		state->dts_errors += buf->dtb_xamot_errors;
323 
324 		/*
325 		 * If the buffers did not actually switch, then the cross call
326 		 * did not take place -- presumably because the given CPU is
327 		 * not in the ready set.  If this is the case, we'll return
328 		 * ENOENT.
329 		 */
330 		if (buf->dtb_tomax == cached) {
331 			ASSERT(buf->dtb_xamot != cached);
332 			mutex_exit(&dtrace_lock);
333 			return (ENOENT);
334 		}
335 
336 		ASSERT(cached == buf->dtb_xamot);
337 
338 		DTRACE_IOCTL_PRINTF("%s(%d): copyout the buffer snapshot\n",__func__,__LINE__);
339 
340 		/*
341 		 * We have our snapshot; now copy it out.
342 		 */
343 		if (copyout(buf->dtb_xamot, desc.dtbd_data,
344 		    buf->dtb_xamot_offset) != 0) {
345 			mutex_exit(&dtrace_lock);
346 			return (EFAULT);
347 		}
348 
349 		desc.dtbd_size = buf->dtb_xamot_offset;
350 		desc.dtbd_drops = buf->dtb_xamot_drops;
351 		desc.dtbd_errors = buf->dtb_xamot_errors;
352 		desc.dtbd_oldest = 0;
353 		desc.dtbd_timestamp = buf->dtb_switched;
354 
355 		mutex_exit(&dtrace_lock);
356 
357 		DTRACE_IOCTL_PRINTF("%s(%d): copyout buffer desc: size %zd drops %lu errors %lu\n",__func__,__LINE__,(size_t) desc.dtbd_size,(u_long) desc.dtbd_drops,(u_long) desc.dtbd_errors);
358 
359 		/*
360 		 * Finally, copy out the buffer description.
361 		 */
362 		if (copyout(&desc, (void *) *pdesc, sizeof (desc)) != 0)
363 			return (EFAULT);
364 
365 		return (0);
366 	}
367 	case DTRACEIOC_CONF: {
368 		dtrace_conf_t conf;
369 
370 		DTRACE_IOCTL_PRINTF("%s(%d): DTRACEIOC_CONF\n",__func__,__LINE__);
371 
372 		bzero(&conf, sizeof (conf));
373 		conf.dtc_difversion = DIF_VERSION;
374 		conf.dtc_difintregs = DIF_DIR_NREGS;
375 		conf.dtc_diftupregs = DIF_DTR_NREGS;
376 		conf.dtc_ctfmodel = CTF_MODEL_NATIVE;
377 
378 		*((dtrace_conf_t *) addr) = conf;
379 
380 		return (0);
381 	}
382 	case DTRACEIOC_DOFGET: {
383 		dof_hdr_t **pdof = (dof_hdr_t **) addr;
384 		dof_hdr_t hdr, *dof = *pdof;
385 		int rval;
386 		uint64_t len;
387 
388 		DTRACE_IOCTL_PRINTF("%s(%d): DTRACEIOC_DOFGET\n",__func__,__LINE__);
389 
390 		if (copyin((void *)dof, &hdr, sizeof (hdr)) != 0)
391 			return (EFAULT);
392 
393 		mutex_enter(&dtrace_lock);
394 		dof = dtrace_dof_create(state);
395 		mutex_exit(&dtrace_lock);
396 
397 		len = MIN(hdr.dofh_loadsz, dof->dofh_loadsz);
398 		rval = copyout(dof, (void *) *pdof, len);
399 		dtrace_dof_destroy(dof);
400 
401 		return (rval == 0 ? 0 : EFAULT);
402 	}
403 	case DTRACEIOC_ENABLE: {
404 		dof_hdr_t *dof = NULL;
405 		dtrace_enabling_t *enab = NULL;
406 		dtrace_vstate_t *vstate;
407 		int err = 0;
408 		int rval;
409 		dtrace_enable_io_t *p = (dtrace_enable_io_t *) addr;
410 
411 		DTRACE_IOCTL_PRINTF("%s(%d): DTRACEIOC_ENABLE\n",__func__,__LINE__);
412 
413 		/*
414 		 * If a NULL argument has been passed, we take this as our
415 		 * cue to reevaluate our enablings.
416 		 */
417 		if (p->dof == NULL) {
418 			dtrace_enabling_matchall();
419 
420 			return (0);
421 		}
422 
423 		if ((dof = dtrace_dof_copyin((uintptr_t) p->dof, &rval)) == NULL)
424 			return (EINVAL);
425 
426 		mutex_enter(&cpu_lock);
427 		mutex_enter(&dtrace_lock);
428 		vstate = &state->dts_vstate;
429 
430 		if (state->dts_activity != DTRACE_ACTIVITY_INACTIVE) {
431 			mutex_exit(&dtrace_lock);
432 			mutex_exit(&cpu_lock);
433 			dtrace_dof_destroy(dof);
434 			return (EBUSY);
435 		}
436 
437 		if (dtrace_dof_slurp(dof, vstate, td->td_ucred, &enab, 0, B_TRUE) != 0) {
438 			mutex_exit(&dtrace_lock);
439 			mutex_exit(&cpu_lock);
440 			dtrace_dof_destroy(dof);
441 			return (EINVAL);
442 		}
443 
444 		if ((rval = dtrace_dof_options(dof, state)) != 0) {
445 			dtrace_enabling_destroy(enab);
446 			mutex_exit(&dtrace_lock);
447 			mutex_exit(&cpu_lock);
448 			dtrace_dof_destroy(dof);
449 			return (rval);
450 		}
451 
452 		if ((err = dtrace_enabling_match(enab, &p->n_matched)) == 0) {
453 			err = dtrace_enabling_retain(enab);
454 		} else {
455 			dtrace_enabling_destroy(enab);
456 		}
457 
458 		mutex_exit(&cpu_lock);
459 		mutex_exit(&dtrace_lock);
460 		dtrace_dof_destroy(dof);
461 
462 		return (err);
463 	}
464 	case DTRACEIOC_EPROBE: {
465 		dtrace_eprobedesc_t **pepdesc = (dtrace_eprobedesc_t **) addr;
466 		dtrace_eprobedesc_t epdesc;
467 		dtrace_ecb_t *ecb;
468 		dtrace_action_t *act;
469 		void *buf;
470 		size_t size;
471 		uintptr_t dest;
472 		int nrecs;
473 
474 		DTRACE_IOCTL_PRINTF("%s(%d): DTRACEIOC_EPROBE\n",__func__,__LINE__);
475 
476 		if (copyin((void *)*pepdesc, &epdesc, sizeof (epdesc)) != 0)
477 			return (EFAULT);
478 
479 		mutex_enter(&dtrace_lock);
480 
481 		if ((ecb = dtrace_epid2ecb(state, epdesc.dtepd_epid)) == NULL) {
482 			mutex_exit(&dtrace_lock);
483 			return (EINVAL);
484 		}
485 
486 		if (ecb->dte_probe == NULL) {
487 			mutex_exit(&dtrace_lock);
488 			return (EINVAL);
489 		}
490 
491 		epdesc.dtepd_probeid = ecb->dte_probe->dtpr_id;
492 		epdesc.dtepd_uarg = ecb->dte_uarg;
493 		epdesc.dtepd_size = ecb->dte_size;
494 
495 		nrecs = epdesc.dtepd_nrecs;
496 		epdesc.dtepd_nrecs = 0;
497 		for (act = ecb->dte_action; act != NULL; act = act->dta_next) {
498 			if (DTRACEACT_ISAGG(act->dta_kind) || act->dta_intuple)
499 				continue;
500 
501 			epdesc.dtepd_nrecs++;
502 		}
503 
504 		/*
505 		 * Now that we have the size, we need to allocate a temporary
506 		 * buffer in which to store the complete description.  We need
507 		 * the temporary buffer to be able to drop dtrace_lock()
508 		 * across the copyout(), below.
509 		 */
510 		size = sizeof (dtrace_eprobedesc_t) +
511 		    (epdesc.dtepd_nrecs * sizeof (dtrace_recdesc_t));
512 
513 		buf = kmem_alloc(size, KM_SLEEP);
514 		dest = (uintptr_t)buf;
515 
516 		bcopy(&epdesc, (void *)dest, sizeof (epdesc));
517 		dest += offsetof(dtrace_eprobedesc_t, dtepd_rec[0]);
518 
519 		for (act = ecb->dte_action; act != NULL; act = act->dta_next) {
520 			if (DTRACEACT_ISAGG(act->dta_kind) || act->dta_intuple)
521 				continue;
522 
523 			if (nrecs-- == 0)
524 				break;
525 
526 			bcopy(&act->dta_rec, (void *)dest,
527 			    sizeof (dtrace_recdesc_t));
528 			dest += sizeof (dtrace_recdesc_t);
529 		}
530 
531 		mutex_exit(&dtrace_lock);
532 
533 		if (copyout(buf, (void *) *pepdesc, dest - (uintptr_t)buf) != 0) {
534 			kmem_free(buf, size);
535 			return (EFAULT);
536 		}
537 
538 		kmem_free(buf, size);
539 		return (0);
540 	}
541 	case DTRACEIOC_FORMAT: {
542 		dtrace_fmtdesc_t *fmt = (dtrace_fmtdesc_t *) addr;
543 		char *str;
544 		int len;
545 
546 		DTRACE_IOCTL_PRINTF("%s(%d): DTRACEIOC_FORMAT\n",__func__,__LINE__);
547 
548 		mutex_enter(&dtrace_lock);
549 
550 		if (fmt->dtfd_format == 0 ||
551 		    fmt->dtfd_format > state->dts_nformats) {
552 			mutex_exit(&dtrace_lock);
553 			return (EINVAL);
554 		}
555 
556 		/*
557 		 * Format strings are allocated contiguously and they are
558 		 * never freed; if a format index is less than the number
559 		 * of formats, we can assert that the format map is non-NULL
560 		 * and that the format for the specified index is non-NULL.
561 		 */
562 		ASSERT(state->dts_formats != NULL);
563 		str = state->dts_formats[fmt->dtfd_format - 1];
564 		ASSERT(str != NULL);
565 
566 		len = strlen(str) + 1;
567 
568 		if (len > fmt->dtfd_length) {
569 			fmt->dtfd_length = len;
570 		} else {
571 			if (copyout(str, fmt->dtfd_string, len) != 0) {
572 				mutex_exit(&dtrace_lock);
573 				return (EINVAL);
574 			}
575 		}
576 
577 		mutex_exit(&dtrace_lock);
578 		return (0);
579 	}
580 	case DTRACEIOC_GO: {
581 		int rval;
582 		processorid_t *cpuid = (processorid_t *) addr;
583 
584 		DTRACE_IOCTL_PRINTF("%s(%d): DTRACEIOC_GO\n",__func__,__LINE__);
585 
586 		rval = dtrace_state_go(state, cpuid);
587 
588 		return (rval);
589 	}
590 	case DTRACEIOC_PROBEARG: {
591 		dtrace_argdesc_t *desc = (dtrace_argdesc_t *) addr;
592 		dtrace_probe_t *probe;
593 		dtrace_provider_t *prov;
594 
595 		DTRACE_IOCTL_PRINTF("%s(%d): DTRACEIOC_PROBEARG\n",__func__,__LINE__);
596 
597 		if (desc->dtargd_id == DTRACE_IDNONE)
598 			return (EINVAL);
599 
600 		if (desc->dtargd_ndx == DTRACE_ARGNONE)
601 			return (EINVAL);
602 
603 		mutex_enter(&dtrace_provider_lock);
604 #ifdef illumos
605 		mutex_enter(&mod_lock);
606 #endif
607 		mutex_enter(&dtrace_lock);
608 
609 		if (desc->dtargd_id > dtrace_nprobes) {
610 			mutex_exit(&dtrace_lock);
611 #ifdef illumos
612 			mutex_exit(&mod_lock);
613 #endif
614 			mutex_exit(&dtrace_provider_lock);
615 			return (EINVAL);
616 		}
617 
618 		if ((probe = dtrace_probes[desc->dtargd_id - 1]) == NULL) {
619 			mutex_exit(&dtrace_lock);
620 #ifdef illumos
621 			mutex_exit(&mod_lock);
622 #endif
623 			mutex_exit(&dtrace_provider_lock);
624 			return (EINVAL);
625 		}
626 
627 		mutex_exit(&dtrace_lock);
628 
629 		prov = probe->dtpr_provider;
630 
631 		if (prov->dtpv_pops.dtps_getargdesc == NULL) {
632 			/*
633 			 * There isn't any typed information for this probe.
634 			 * Set the argument number to DTRACE_ARGNONE.
635 			 */
636 			desc->dtargd_ndx = DTRACE_ARGNONE;
637 		} else {
638 			desc->dtargd_native[0] = '\0';
639 			desc->dtargd_xlate[0] = '\0';
640 			desc->dtargd_mapping = desc->dtargd_ndx;
641 
642 			prov->dtpv_pops.dtps_getargdesc(prov->dtpv_arg,
643 			    probe->dtpr_id, probe->dtpr_arg, desc);
644 		}
645 
646 #ifdef illumos
647 		mutex_exit(&mod_lock);
648 #endif
649 		mutex_exit(&dtrace_provider_lock);
650 
651 		return (0);
652 	}
653 	case DTRACEIOC_PROBEMATCH:
654 	case DTRACEIOC_PROBES: {
655 		dtrace_probedesc_t *p_desc = (dtrace_probedesc_t *) addr;
656 		dtrace_probe_t *probe = NULL;
657 		dtrace_probekey_t pkey;
658 		dtrace_id_t i;
659 		int m = 0;
660 		uint32_t priv = 0;
661 		uid_t uid = 0;
662 		zoneid_t zoneid = 0;
663 
664 		DTRACE_IOCTL_PRINTF("%s(%d): %s\n",__func__,__LINE__,
665 		    cmd == DTRACEIOC_PROBEMATCH ?
666 		    "DTRACEIOC_PROBEMATCH":"DTRACEIOC_PROBES");
667 
668 		p_desc->dtpd_provider[DTRACE_PROVNAMELEN - 1] = '\0';
669 		p_desc->dtpd_mod[DTRACE_MODNAMELEN - 1] = '\0';
670 		p_desc->dtpd_func[DTRACE_FUNCNAMELEN - 1] = '\0';
671 		p_desc->dtpd_name[DTRACE_NAMELEN - 1] = '\0';
672 
673 		/*
674 		 * Before we attempt to match this probe, we want to give
675 		 * all providers the opportunity to provide it.
676 		 */
677 		if (p_desc->dtpd_id == DTRACE_IDNONE) {
678 			mutex_enter(&dtrace_provider_lock);
679 			dtrace_probe_provide(p_desc, NULL);
680 			mutex_exit(&dtrace_provider_lock);
681 			p_desc->dtpd_id++;
682 		}
683 
684 		if (cmd == DTRACEIOC_PROBEMATCH)  {
685 			dtrace_probekey(p_desc, &pkey);
686 			pkey.dtpk_id = DTRACE_IDNONE;
687 		}
688 
689 		dtrace_cred2priv(td->td_ucred, &priv, &uid, &zoneid);
690 
691 		mutex_enter(&dtrace_lock);
692 
693 		if (cmd == DTRACEIOC_PROBEMATCH) {
694 			for (i = p_desc->dtpd_id; i <= dtrace_nprobes; i++) {
695 				if ((probe = dtrace_probes[i - 1]) != NULL &&
696 				    (m = dtrace_match_probe(probe, &pkey,
697 				    priv, uid, zoneid)) != 0)
698 					break;
699 			}
700 
701 			if (m < 0) {
702 				mutex_exit(&dtrace_lock);
703 				return (EINVAL);
704 			}
705 
706 		} else {
707 			for (i = p_desc->dtpd_id; i <= dtrace_nprobes; i++) {
708 				if ((probe = dtrace_probes[i - 1]) != NULL &&
709 				    dtrace_match_priv(probe, priv, uid, zoneid))
710 					break;
711 			}
712 		}
713 
714 		if (probe == NULL) {
715 			mutex_exit(&dtrace_lock);
716 			return (ESRCH);
717 		}
718 
719 		dtrace_probe_description(probe, p_desc);
720 		mutex_exit(&dtrace_lock);
721 
722 		return (0);
723 	}
724 	case DTRACEIOC_PROVIDER: {
725 		dtrace_providerdesc_t *pvd = (dtrace_providerdesc_t *) addr;
726 		dtrace_provider_t *pvp;
727 
728 		DTRACE_IOCTL_PRINTF("%s(%d): DTRACEIOC_PROVIDER\n",__func__,__LINE__);
729 
730 		pvd->dtvd_name[DTRACE_PROVNAMELEN - 1] = '\0';
731 		mutex_enter(&dtrace_provider_lock);
732 
733 		for (pvp = dtrace_provider; pvp != NULL; pvp = pvp->dtpv_next) {
734 			if (strcmp(pvp->dtpv_name, pvd->dtvd_name) == 0)
735 				break;
736 		}
737 
738 		mutex_exit(&dtrace_provider_lock);
739 
740 		if (pvp == NULL)
741 			return (ESRCH);
742 
743 		bcopy(&pvp->dtpv_priv, &pvd->dtvd_priv, sizeof (dtrace_ppriv_t));
744 		bcopy(&pvp->dtpv_attr, &pvd->dtvd_attr, sizeof (dtrace_pattr_t));
745 
746 		return (0);
747 	}
748 	case DTRACEIOC_REPLICATE: {
749 		dtrace_repldesc_t *desc = (dtrace_repldesc_t *) addr;
750 		dtrace_probedesc_t *match = &desc->dtrpd_match;
751 		dtrace_probedesc_t *create = &desc->dtrpd_create;
752 		int err;
753 
754 		DTRACE_IOCTL_PRINTF("%s(%d): DTRACEIOC_REPLICATE\n",__func__,__LINE__);
755 
756 		match->dtpd_provider[DTRACE_PROVNAMELEN - 1] = '\0';
757 		match->dtpd_mod[DTRACE_MODNAMELEN - 1] = '\0';
758 		match->dtpd_func[DTRACE_FUNCNAMELEN - 1] = '\0';
759 		match->dtpd_name[DTRACE_NAMELEN - 1] = '\0';
760 
761 		create->dtpd_provider[DTRACE_PROVNAMELEN - 1] = '\0';
762 		create->dtpd_mod[DTRACE_MODNAMELEN - 1] = '\0';
763 		create->dtpd_func[DTRACE_FUNCNAMELEN - 1] = '\0';
764 		create->dtpd_name[DTRACE_NAMELEN - 1] = '\0';
765 
766 		mutex_enter(&dtrace_lock);
767 		err = dtrace_enabling_replicate(state, match, create);
768 		mutex_exit(&dtrace_lock);
769 
770 		return (err);
771 	}
772 	case DTRACEIOC_STATUS: {
773 		dtrace_status_t *stat = (dtrace_status_t *) addr;
774 		dtrace_dstate_t *dstate;
775 		int i, j;
776 		uint64_t nerrs;
777 
778 		DTRACE_IOCTL_PRINTF("%s(%d): DTRACEIOC_STATUS\n",__func__,__LINE__);
779 
780 		/*
781 		 * See the comment in dtrace_state_deadman() for the reason
782 		 * for setting dts_laststatus to INT64_MAX before setting
783 		 * it to the correct value.
784 		 */
785 		state->dts_laststatus = INT64_MAX;
786 		dtrace_membar_producer();
787 		state->dts_laststatus = dtrace_gethrtime();
788 
789 		bzero(stat, sizeof (*stat));
790 
791 		mutex_enter(&dtrace_lock);
792 
793 		if (state->dts_activity == DTRACE_ACTIVITY_INACTIVE) {
794 			mutex_exit(&dtrace_lock);
795 			return (ENOENT);
796 		}
797 
798 		if (state->dts_activity == DTRACE_ACTIVITY_DRAINING)
799 			stat->dtst_exiting = 1;
800 
801 		nerrs = state->dts_errors;
802 		dstate = &state->dts_vstate.dtvs_dynvars;
803 
804 		for (i = 0; i < NCPU; i++) {
805 #ifndef illumos
806 			if (pcpu_find(i) == NULL)
807 				continue;
808 #endif
809 			dtrace_dstate_percpu_t *dcpu = &dstate->dtds_percpu[i];
810 
811 			stat->dtst_dyndrops += dcpu->dtdsc_drops;
812 			stat->dtst_dyndrops_dirty += dcpu->dtdsc_dirty_drops;
813 			stat->dtst_dyndrops_rinsing += dcpu->dtdsc_rinsing_drops;
814 
815 			if (state->dts_buffer[i].dtb_flags & DTRACEBUF_FULL)
816 				stat->dtst_filled++;
817 
818 			nerrs += state->dts_buffer[i].dtb_errors;
819 
820 			for (j = 0; j < state->dts_nspeculations; j++) {
821 				dtrace_speculation_t *spec;
822 				dtrace_buffer_t *buf;
823 
824 				spec = &state->dts_speculations[j];
825 				buf = &spec->dtsp_buffer[i];
826 				stat->dtst_specdrops += buf->dtb_xamot_drops;
827 			}
828 		}
829 
830 		stat->dtst_specdrops_busy = state->dts_speculations_busy;
831 		stat->dtst_specdrops_unavail = state->dts_speculations_unavail;
832 		stat->dtst_stkstroverflows = state->dts_stkstroverflows;
833 		stat->dtst_dblerrors = state->dts_dblerrors;
834 		stat->dtst_killed =
835 		    (state->dts_activity == DTRACE_ACTIVITY_KILLED);
836 		stat->dtst_errors = nerrs;
837 
838 		mutex_exit(&dtrace_lock);
839 
840 		return (0);
841 	}
842 	case DTRACEIOC_STOP: {
843 		int rval;
844 		processorid_t *cpuid = (processorid_t *) addr;
845 
846 		DTRACE_IOCTL_PRINTF("%s(%d): DTRACEIOC_STOP\n",__func__,__LINE__);
847 
848 		mutex_enter(&dtrace_lock);
849 		rval = dtrace_state_stop(state, cpuid);
850 		mutex_exit(&dtrace_lock);
851 
852 		return (rval);
853 	}
854 	default:
855 		error = ENOTTY;
856 	}
857 	return (error);
858 }
859