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 * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
23 * Copyright (c) 2012, 2015 by Delphix. All rights reserved.
24 */
25
26 /*
27 * ZFS fault injection
28 *
29 * To handle fault injection, we keep track of a series of zinject_record_t
30 * structures which describe which logical block(s) should be injected with a
31 * fault. These are kept in a global list. Each record corresponds to a given
32 * spa_t and maintains a special hold on the spa_t so that it cannot be deleted
33 * or exported while the injection record exists.
34 *
35 * Device level injection is done using the 'zi_guid' field. If this is set, it
36 * means that the error is destined for a particular device, not a piece of
37 * data.
38 *
39 * This is a rather poor data structure and algorithm, but we don't expect more
40 * than a few faults at any one time, so it should be sufficient for our needs.
41 */
42
43 #include <sys/arc.h>
44 #include <sys/zio_impl.h>
45 #include <sys/zfs_ioctl.h>
46 #include <sys/vdev_impl.h>
47 #include <sys/dmu_objset.h>
48 #include <sys/fs/zfs.h>
49
50 uint32_t zio_injection_enabled;
51
52 /*
53 * Data describing each zinject handler registered on the system, and
54 * contains the list node linking the handler in the global zinject
55 * handler list.
56 */
57 typedef struct inject_handler {
58 int zi_id;
59 spa_t *zi_spa;
60 zinject_record_t zi_record;
61 uint64_t *zi_lanes;
62 int zi_next_lane;
63 list_node_t zi_link;
64 } inject_handler_t;
65
66 /*
67 * List of all zinject handlers registered on the system, protected by
68 * the inject_lock defined below.
69 */
70 static list_t inject_handlers;
71
72 /*
73 * This protects insertion into, and traversal of, the inject handler
74 * list defined above; as well as the inject_delay_count. Any time a
75 * handler is inserted or removed from the list, this lock should be
76 * taken as a RW_WRITER; and any time traversal is done over the list
77 * (without modification to it) this lock should be taken as a RW_READER.
78 */
79 static krwlock_t inject_lock;
80
81 /*
82 * This holds the number of zinject delay handlers that have been
83 * registered on the system. It is protected by the inject_lock defined
84 * above. Thus modifications to this count must be a RW_WRITER of the
85 * inject_lock, and reads of this count must be (at least) a RW_READER
86 * of the lock.
87 */
88 static int inject_delay_count = 0;
89
90 /*
91 * This lock is used only in zio_handle_io_delay(), refer to the comment
92 * in that function for more details.
93 */
94 static kmutex_t inject_delay_mtx;
95
96 /*
97 * Used to assign unique identifying numbers to each new zinject handler.
98 */
99 static int inject_next_id = 1;
100
101 /*
102 * Returns true if the given record matches the I/O in progress.
103 */
104 static boolean_t
105 zio_match_handler(zbookmark_phys_t *zb, uint64_t type,
106 zinject_record_t *record, int error)
107 {
108 /*
109 * Check for a match against the MOS, which is based on type
110 */
111 if (zb->zb_objset == DMU_META_OBJSET &&
112 record->zi_objset == DMU_META_OBJSET &&
113 record->zi_object == DMU_META_DNODE_OBJECT) {
114 if (record->zi_type == DMU_OT_NONE ||
115 type == record->zi_type)
116 return (record->zi_freq == 0 ||
117 spa_get_random(100) < record->zi_freq);
118 else
119 return (B_FALSE);
120 }
121
122 /*
123 * Check for an exact match.
124 */
125 if (zb->zb_objset == record->zi_objset &&
126 zb->zb_object == record->zi_object &&
127 zb->zb_level == record->zi_level &&
128 zb->zb_blkid >= record->zi_start &&
129 zb->zb_blkid <= record->zi_end &&
130 error == record->zi_error)
131 return (record->zi_freq == 0 ||
132 spa_get_random(100) < record->zi_freq);
133
134 return (B_FALSE);
135 }
136
137 /*
138 * Panic the system when a config change happens in the function
139 * specified by tag.
140 */
141 void
142 zio_handle_panic_injection(spa_t *spa, char *tag, uint64_t type)
143 {
144 inject_handler_t *handler;
145
146 rw_enter(&inject_lock, RW_READER);
147
148 for (handler = list_head(&inject_handlers); handler != NULL;
149 handler = list_next(&inject_handlers, handler)) {
150
151 if (spa != handler->zi_spa)
152 continue;
153
154 if (handler->zi_record.zi_type == type &&
155 strcmp(tag, handler->zi_record.zi_func) == 0)
156 panic("Panic requested in function %s\n", tag);
157 }
158
159 rw_exit(&inject_lock);
160 }
161
162 /*
163 * Determine if the I/O in question should return failure. Returns the errno
164 * to be returned to the caller.
165 */
166 int
167 zio_handle_fault_injection(zio_t *zio, int error)
168 {
169 int ret = 0;
170 inject_handler_t *handler;
171
172 /*
173 * Ignore I/O not associated with any logical data.
174 */
175 if (zio->io_logical == NULL)
176 return (0);
177
178 /*
179 * Currently, we only support fault injection on reads.
180 */
181 if (zio->io_type != ZIO_TYPE_READ)
182 return (0);
183
184 rw_enter(&inject_lock, RW_READER);
185
186 for (handler = list_head(&inject_handlers); handler != NULL;
187 handler = list_next(&inject_handlers, handler)) {
188
189 if (zio->io_spa != handler->zi_spa ||
190 handler->zi_record.zi_cmd != ZINJECT_DATA_FAULT)
191 continue;
192
193 /* If this handler matches, return EIO */
194 if (zio_match_handler(&zio->io_logical->io_bookmark,
195 zio->io_bp ? BP_GET_TYPE(zio->io_bp) : DMU_OT_NONE,
196 &handler->zi_record, error)) {
197 ret = error;
198 break;
199 }
200 }
201
202 rw_exit(&inject_lock);
203
204 return (ret);
205 }
206
207 /*
208 * Determine if the zio is part of a label update and has an injection
209 * handler associated with that portion of the label. Currently, we
210 * allow error injection in either the nvlist or the uberblock region of
211 * of the vdev label.
212 */
213 int
214 zio_handle_label_injection(zio_t *zio, int error)
215 {
216 inject_handler_t *handler;
217 vdev_t *vd = zio->io_vd;
218 uint64_t offset = zio->io_offset;
219 int label;
220 int ret = 0;
221
222 if (offset >= VDEV_LABEL_START_SIZE &&
223 offset < vd->vdev_psize - VDEV_LABEL_END_SIZE)
224 return (0);
225
226 rw_enter(&inject_lock, RW_READER);
227
228 for (handler = list_head(&inject_handlers); handler != NULL;
229 handler = list_next(&inject_handlers, handler)) {
230 uint64_t start = handler->zi_record.zi_start;
231 uint64_t end = handler->zi_record.zi_end;
232
233 if (handler->zi_record.zi_cmd != ZINJECT_LABEL_FAULT)
234 continue;
235
236 /*
237 * The injection region is the relative offsets within a
238 * vdev label. We must determine the label which is being
239 * updated and adjust our region accordingly.
240 */
241 label = vdev_label_number(vd->vdev_psize, offset);
242 start = vdev_label_offset(vd->vdev_psize, label, start);
243 end = vdev_label_offset(vd->vdev_psize, label, end);
244
245 if (zio->io_vd->vdev_guid == handler->zi_record.zi_guid &&
246 (offset >= start && offset <= end)) {
247 ret = error;
248 break;
249 }
250 }
251 rw_exit(&inject_lock);
252 return (ret);
253 }
254
255
256 int
257 zio_handle_device_injection(vdev_t *vd, zio_t *zio, int error)
258 {
259 inject_handler_t *handler;
260 int ret = 0;
261
262 /*
263 * We skip over faults in the labels unless it's during
264 * device open (i.e. zio == NULL).
265 */
266 if (zio != NULL) {
267 uint64_t offset = zio->io_offset;
268
269 if (offset < VDEV_LABEL_START_SIZE ||
270 offset >= vd->vdev_psize - VDEV_LABEL_END_SIZE)
271 return (0);
272 }
273
274 rw_enter(&inject_lock, RW_READER);
275
276 for (handler = list_head(&inject_handlers); handler != NULL;
277 handler = list_next(&inject_handlers, handler)) {
278
279 if (handler->zi_record.zi_cmd != ZINJECT_DEVICE_FAULT)
280 continue;
281
282 if (vd->vdev_guid == handler->zi_record.zi_guid) {
283 if (handler->zi_record.zi_failfast &&
284 (zio == NULL || (zio->io_flags &
285 (ZIO_FLAG_IO_RETRY | ZIO_FLAG_TRYHARD)))) {
286 continue;
287 }
288
289 /* Handle type specific I/O failures */
290 if (zio != NULL &&
291 handler->zi_record.zi_iotype != ZIO_TYPES &&
292 handler->zi_record.zi_iotype != zio->io_type)
293 continue;
294
295 if (handler->zi_record.zi_error == error) {
296 /*
297 * For a failed open, pretend like the device
298 * has gone away.
299 */
300 if (error == ENXIO)
301 vd->vdev_stat.vs_aux =
302 VDEV_AUX_OPEN_FAILED;
303
304 /*
305 * Treat these errors as if they had been
306 * retried so that all the appropriate stats
307 * and FMA events are generated.
308 */
309 if (!handler->zi_record.zi_failfast &&
310 zio != NULL)
311 zio->io_flags |= ZIO_FLAG_IO_RETRY;
312
313 ret = error;
314 break;
315 }
316 if (handler->zi_record.zi_error == ENXIO) {
317 ret = SET_ERROR(EIO);
318 break;
319 }
320 }
321 }
322
323 rw_exit(&inject_lock);
324
325 return (ret);
326 }
327
328 /*
329 * Simulate hardware that ignores cache flushes. For requested number
330 * of seconds nix the actual writing to disk.
331 */
332 void
333 zio_handle_ignored_writes(zio_t *zio)
334 {
335 inject_handler_t *handler;
336
337 rw_enter(&inject_lock, RW_READER);
338
339 for (handler = list_head(&inject_handlers); handler != NULL;
340 handler = list_next(&inject_handlers, handler)) {
341
342 /* Ignore errors not destined for this pool */
343 if (zio->io_spa != handler->zi_spa ||
344 handler->zi_record.zi_cmd != ZINJECT_IGNORED_WRITES)
345 continue;
346
347 /*
348 * Positive duration implies # of seconds, negative
349 * a number of txgs
350 */
351 if (handler->zi_record.zi_timer == 0) {
352 if (handler->zi_record.zi_duration > 0)
353 handler->zi_record.zi_timer = ddi_get_lbolt64();
354 else
355 handler->zi_record.zi_timer = zio->io_txg;
356 }
357
358 /* Have a "problem" writing 60% of the time */
359 if (spa_get_random(100) < 60)
360 zio->io_pipeline &= ~ZIO_VDEV_IO_STAGES;
361 break;
362 }
363
364 rw_exit(&inject_lock);
365 }
366
367 void
368 spa_handle_ignored_writes(spa_t *spa)
369 {
370 inject_handler_t *handler;
371
372 if (zio_injection_enabled == 0)
373 return;
374
375 rw_enter(&inject_lock, RW_READER);
376
377 for (handler = list_head(&inject_handlers); handler != NULL;
378 handler = list_next(&inject_handlers, handler)) {
379
380 if (spa != handler->zi_spa ||
381 handler->zi_record.zi_cmd != ZINJECT_IGNORED_WRITES)
382 continue;
383
384 if (handler->zi_record.zi_duration > 0) {
385 VERIFY(handler->zi_record.zi_timer == 0 ||
386 handler->zi_record.zi_timer +
387 handler->zi_record.zi_duration * hz >
388 ddi_get_lbolt64());
389 } else {
390 /* duration is negative so the subtraction here adds */
391 VERIFY(handler->zi_record.zi_timer == 0 ||
392 handler->zi_record.zi_timer -
393 handler->zi_record.zi_duration >=
394 spa_syncing_txg(spa));
395 }
396 }
397
398 rw_exit(&inject_lock);
399 }
400
401 hrtime_t
402 zio_handle_io_delay(zio_t *zio)
403 {
404 vdev_t *vd = zio->io_vd;
405 inject_handler_t *min_handler = NULL;
406 hrtime_t min_target = 0;
407
408 rw_enter(&inject_lock, RW_READER);
409
410 /*
411 * inject_delay_count is a subset of zio_injection_enabled that
412 * is only incremented for delay handlers. These checks are
413 * mainly added to remind the reader why we're not explicitly
414 * checking zio_injection_enabled like the other functions.
415 */
416 IMPLY(inject_delay_count > 0, zio_injection_enabled > 0);
417 IMPLY(zio_injection_enabled == 0, inject_delay_count == 0);
418
419 /*
420 * If there aren't any inject delay handlers registered, then we
421 * can short circuit and simply return 0 here. A value of zero
422 * informs zio_delay_interrupt() that this request should not be
423 * delayed. This short circuit keeps us from acquiring the
424 * inject_delay_mutex unnecessarily.
425 */
426 if (inject_delay_count == 0) {
427 rw_exit(&inject_lock);
428 return (0);
429 }
430
431 /*
432 * Each inject handler has a number of "lanes" associated with
433 * it. Each lane is able to handle requests independently of one
434 * another, and at a latency defined by the inject handler
435 * record's zi_timer field. Thus if a handler in configured with
436 * a single lane with a 10ms latency, it will delay requests
437 * such that only a single request is completed every 10ms. So,
438 * if more than one request is attempted per each 10ms interval,
439 * the average latency of the requests will be greater than
440 * 10ms; but if only a single request is submitted each 10ms
441 * interval the average latency will be 10ms.
442 *
443 * We need to acquire this mutex to prevent multiple concurrent
444 * threads being assigned to the same lane of a given inject
445 * handler. The mutex allows us to perform the following two
446 * operations atomically:
447 *
448 * 1. determine the minimum handler and minimum target
449 * value of all the possible handlers
450 * 2. update that minimum handler's lane array
451 *
452 * Without atomicity, two (or more) threads could pick the same
453 * lane in step (1), and then conflict with each other in step
454 * (2). This could allow a single lane handler to process
455 * multiple requests simultaneously, which shouldn't be possible.
456 */
457 mutex_enter(&inject_delay_mtx);
458
459 for (inject_handler_t *handler = list_head(&inject_handlers);
460 handler != NULL; handler = list_next(&inject_handlers, handler)) {
461 if (handler->zi_record.zi_cmd != ZINJECT_DELAY_IO)
462 continue;
463
464 if (vd->vdev_guid != handler->zi_record.zi_guid)
465 continue;
466
467 /*
468 * Defensive; should never happen as the array allocation
469 * occurs prior to inserting this handler on the list.
470 */
471 ASSERT3P(handler->zi_lanes, !=, NULL);
472
473 /*
474 * This should never happen, the zinject command should
475 * prevent a user from setting an IO delay with zero lanes.
476 */
477 ASSERT3U(handler->zi_record.zi_nlanes, !=, 0);
478
479 ASSERT3U(handler->zi_record.zi_nlanes, >,
480 handler->zi_next_lane);
481
482 /*
483 * We want to issue this IO to the lane that will become
484 * idle the soonest, so we compare the soonest this
485 * specific handler can complete the IO with all other
486 * handlers, to find the lowest value of all possible
487 * lanes. We then use this lane to submit the request.
488 *
489 * Since each handler has a constant value for its
490 * delay, we can just use the "next" lane for that
491 * handler; as it will always be the lane with the
492 * lowest value for that particular handler (i.e. the
493 * lane that will become idle the soonest). This saves a
494 * scan of each handler's lanes array.
495 *
496 * There's two cases to consider when determining when
497 * this specific IO request should complete. If this
498 * lane is idle, we want to "submit" the request now so
499 * it will complete after zi_timer milliseconds. Thus,
500 * we set the target to now + zi_timer.
501 *
502 * If the lane is busy, we want this request to complete
503 * zi_timer milliseconds after the lane becomes idle.
504 * Since the 'zi_lanes' array holds the time at which
505 * each lane will become idle, we use that value to
506 * determine when this request should complete.
507 */
508 hrtime_t idle = handler->zi_record.zi_timer + gethrtime();
509 hrtime_t busy = handler->zi_record.zi_timer +
510 handler->zi_lanes[handler->zi_next_lane];
511 hrtime_t target = MAX(idle, busy);
512
513 if (min_handler == NULL) {
514 min_handler = handler;
515 min_target = target;
516 continue;
517 }
518
519 ASSERT3P(min_handler, !=, NULL);
520 ASSERT3U(min_target, !=, 0);
521
522 /*
523 * We don't yet increment the "next lane" variable since
524 * we still might find a lower value lane in another
525 * handler during any remaining iterations. Once we're
526 * sure we've selected the absolute minimum, we'll claim
527 * the lane and increment the handler's "next lane"
528 * field below.
529 */
530
531 if (target < min_target) {
532 min_handler = handler;
533 min_target = target;
534 }
535 }
536
537 /*
538 * 'min_handler' will be NULL if no IO delays are registered for
539 * this vdev, otherwise it will point to the handler containing
540 * the lane that will become idle the soonest.
541 */
542 if (min_handler != NULL) {
543 ASSERT3U(min_target, !=, 0);
544 min_handler->zi_lanes[min_handler->zi_next_lane] = min_target;
545
546 /*
547 * If we've used all possible lanes for this handler,
548 * loop back and start using the first lane again;
549 * otherwise, just increment the lane index.
550 */
551 min_handler->zi_next_lane = (min_handler->zi_next_lane + 1) %
552 min_handler->zi_record.zi_nlanes;
553 }
554
555 mutex_exit(&inject_delay_mtx);
556 rw_exit(&inject_lock);
557
558 return (min_target);
559 }
560
561 /*
562 * Create a new handler for the given record. We add it to the list, adding
563 * a reference to the spa_t in the process. We increment zio_injection_enabled,
564 * which is the switch to trigger all fault injection.
565 */
566 int
567 zio_inject_fault(char *name, int flags, int *id, zinject_record_t *record)
568 {
569 inject_handler_t *handler;
570 int error;
571 spa_t *spa;
572
573 /*
574 * If this is pool-wide metadata, make sure we unload the corresponding
575 * spa_t, so that the next attempt to load it will trigger the fault.
576 * We call spa_reset() to unload the pool appropriately.
577 */
578 if (flags & ZINJECT_UNLOAD_SPA)
579 if ((error = spa_reset(name)) != 0)
580 return (error);
581
582 if (record->zi_cmd == ZINJECT_DELAY_IO) {
583 /*
584 * A value of zero for the number of lanes or for the
585 * delay time doesn't make sense.
586 */
587 if (record->zi_timer == 0 || record->zi_nlanes == 0)
588 return (SET_ERROR(EINVAL));
589
590 /*
591 * The number of lanes is directly mapped to the size of
592 * an array used by the handler. Thus, to ensure the
593 * user doesn't trigger an allocation that's "too large"
594 * we cap the number of lanes here.
595 */
596 if (record->zi_nlanes >= UINT16_MAX)
597 return (SET_ERROR(EINVAL));
598 }
599
600 if (!(flags & ZINJECT_NULL)) {
601 /*
602 * spa_inject_ref() will add an injection reference, which will
603 * prevent the pool from being removed from the namespace while
604 * still allowing it to be unloaded.
605 */
606 if ((spa = spa_inject_addref(name)) == NULL)
607 return (SET_ERROR(ENOENT));
608
609 handler = kmem_alloc(sizeof (inject_handler_t), KM_SLEEP);
610
611 handler->zi_spa = spa;
612 handler->zi_record = *record;
613
614 if (handler->zi_record.zi_cmd == ZINJECT_DELAY_IO) {
615 handler->zi_lanes = kmem_zalloc(
616 sizeof (*handler->zi_lanes) *
617 handler->zi_record.zi_nlanes, KM_SLEEP);
618 handler->zi_next_lane = 0;
619 } else {
620 handler->zi_lanes = NULL;
621 handler->zi_next_lane = 0;
622 }
623
624 rw_enter(&inject_lock, RW_WRITER);
625
626 /*
627 * We can't move this increment into the conditional
628 * above because we need to hold the RW_WRITER lock of
629 * inject_lock, and we don't want to hold that while
630 * allocating the handler's zi_lanes array.
631 */
632 if (handler->zi_record.zi_cmd == ZINJECT_DELAY_IO) {
633 ASSERT3S(inject_delay_count, >=, 0);
634 inject_delay_count++;
635 ASSERT3S(inject_delay_count, >, 0);
636 }
637
638 *id = handler->zi_id = inject_next_id++;
639 list_insert_tail(&inject_handlers, handler);
640 atomic_inc_32(&zio_injection_enabled);
641
642 rw_exit(&inject_lock);
643 }
644
645 /*
646 * Flush the ARC, so that any attempts to read this data will end up
647 * going to the ZIO layer. Note that this is a little overkill, but
648 * we don't have the necessary ARC interfaces to do anything else, and
649 * fault injection isn't a performance critical path.
650 */
651 if (flags & ZINJECT_FLUSH_ARC)
652 /*
653 * We must use FALSE to ensure arc_flush returns, since
654 * we're not preventing concurrent ARC insertions.
655 */
656 arc_flush(NULL, FALSE);
657
658 return (0);
659 }
660
661 /*
662 * Returns the next record with an ID greater than that supplied to the
663 * function. Used to iterate over all handlers in the system.
664 */
665 int
666 zio_inject_list_next(int *id, char *name, size_t buflen,
667 zinject_record_t *record)
668 {
669 inject_handler_t *handler;
670 int ret;
671
672 mutex_enter(&spa_namespace_lock);
673 rw_enter(&inject_lock, RW_READER);
674
675 for (handler = list_head(&inject_handlers); handler != NULL;
676 handler = list_next(&inject_handlers, handler))
677 if (handler->zi_id > *id)
678 break;
679
680 if (handler) {
681 *record = handler->zi_record;
682 *id = handler->zi_id;
683 (void) strncpy(name, spa_name(handler->zi_spa), buflen);
684 ret = 0;
685 } else {
686 ret = SET_ERROR(ENOENT);
687 }
688
689 rw_exit(&inject_lock);
690 mutex_exit(&spa_namespace_lock);
691
692 return (ret);
693 }
694
695 /*
696 * Clear the fault handler with the given identifier, or return ENOENT if none
697 * exists.
698 */
699 int
700 zio_clear_fault(int id)
701 {
702 inject_handler_t *handler;
703
704 rw_enter(&inject_lock, RW_WRITER);
705
706 for (handler = list_head(&inject_handlers); handler != NULL;
707 handler = list_next(&inject_handlers, handler))
708 if (handler->zi_id == id)
709 break;
710
711 if (handler == NULL) {
712 rw_exit(&inject_lock);
713 return (SET_ERROR(ENOENT));
714 }
715
716 if (handler->zi_record.zi_cmd == ZINJECT_DELAY_IO) {
717 ASSERT3S(inject_delay_count, >, 0);
718 inject_delay_count--;
719 ASSERT3S(inject_delay_count, >=, 0);
720 }
721
722 list_remove(&inject_handlers, handler);
723 rw_exit(&inject_lock);
724
725 if (handler->zi_record.zi_cmd == ZINJECT_DELAY_IO) {
726 ASSERT3P(handler->zi_lanes, !=, NULL);
727 kmem_free(handler->zi_lanes, sizeof (*handler->zi_lanes) *
728 handler->zi_record.zi_nlanes);
729 } else {
730 ASSERT3P(handler->zi_lanes, ==, NULL);
731 }
732
733 spa_inject_delref(handler->zi_spa);
734 kmem_free(handler, sizeof (inject_handler_t));
735 atomic_dec_32(&zio_injection_enabled);
736
737 return (0);
738 }
739
740 void
741 zio_inject_init(void)
742 {
743 rw_init(&inject_lock, NULL, RW_DEFAULT, NULL);
744 mutex_init(&inject_delay_mtx, NULL, MUTEX_DEFAULT, NULL);
745 list_create(&inject_handlers, sizeof (inject_handler_t),
746 offsetof(inject_handler_t, zi_link));
747 }
748
749 void
750 zio_inject_fini(void)
751 {
752 list_destroy(&inject_handlers);
753 mutex_destroy(&inject_delay_mtx);
754 rw_destroy(&inject_lock);
755 }