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 2010 Sun Microsystems, Inc. All rights reserved.
23 * Use is subject to license terms.
24 */
25
26 /*
27 * Copyright (c) 2012, 2018 by Delphix. All rights reserved.
28 */
29
30 #include <sys/zfs_context.h>
31 #include <sys/spa.h>
32 #include <sys/spa_impl.h>
33 #include <sys/dsl_pool.h>
34 #include <sys/dsl_scan.h>
35 #include <sys/vdev_impl.h>
36 #include <sys/zio.h>
37 #include <sys/abd.h>
38 #include <sys/fs/zfs.h>
39
40 /*
41 * Virtual device vector for mirroring.
42 */
43
44 typedef struct mirror_child {
45 vdev_t *mc_vd;
46 uint64_t mc_offset;
47 int mc_error;
48 int mc_load;
49 uint8_t mc_tried;
50 uint8_t mc_skipped;
51 uint8_t mc_speculative;
52 } mirror_child_t;
53
54 typedef struct mirror_map {
55 int *mm_preferred;
56 int mm_preferred_cnt;
57 int mm_children;
58 boolean_t mm_resilvering;
59 boolean_t mm_root;
60 mirror_child_t mm_child[];
61 } mirror_map_t;
62
63 static int vdev_mirror_shift = 21;
64
65 #ifdef _KERNEL
66 SYSCTL_DECL(_vfs_zfs_vdev);
67 static SYSCTL_NODE(_vfs_zfs_vdev, OID_AUTO, mirror, CTLFLAG_RD, 0,
68 "ZFS VDEV Mirror");
69 #endif
70
71 /*
72 * The load configuration settings below are tuned by default for
73 * the case where all devices are of the same rotational type.
74 *
75 * If there is a mixture of rotating and non-rotating media, setting
76 * non_rotating_seek_inc to 0 may well provide better results as it
77 * will direct more reads to the non-rotating vdevs which are more
78 * likely to have a higher performance.
79 */
80
81 /* Rotating media load calculation configuration. */
82 static int rotating_inc = 0;
83 #ifdef _KERNEL
84 SYSCTL_INT(_vfs_zfs_vdev_mirror, OID_AUTO, rotating_inc, CTLFLAG_RWTUN,
85 &rotating_inc, 0, "Rotating media load increment for non-seeking I/O's");
86 #endif
87
88 static int rotating_seek_inc = 5;
89 #ifdef _KERNEL
90 SYSCTL_INT(_vfs_zfs_vdev_mirror, OID_AUTO, rotating_seek_inc, CTLFLAG_RWTUN,
91 &rotating_seek_inc, 0, "Rotating media load increment for seeking I/O's");
92 #endif
93
94 static int rotating_seek_offset = 1 * 1024 * 1024;
95 #ifdef _KERNEL
96 SYSCTL_INT(_vfs_zfs_vdev_mirror, OID_AUTO, rotating_seek_offset, CTLFLAG_RWTUN,
97 &rotating_seek_offset, 0, "Offset in bytes from the last I/O which "
98 "triggers a reduced rotating media seek increment");
99 #endif
100
101 /* Non-rotating media load calculation configuration. */
102 static int non_rotating_inc = 0;
103 #ifdef _KERNEL
104 SYSCTL_INT(_vfs_zfs_vdev_mirror, OID_AUTO, non_rotating_inc, CTLFLAG_RWTUN,
105 &non_rotating_inc, 0,
106 "Non-rotating media load increment for non-seeking I/O's");
107 #endif
108
109 static int non_rotating_seek_inc = 1;
110 #ifdef _KERNEL
111 SYSCTL_INT(_vfs_zfs_vdev_mirror, OID_AUTO, non_rotating_seek_inc, CTLFLAG_RWTUN,
112 &non_rotating_seek_inc, 0,
113 "Non-rotating media load increment for seeking I/O's");
114 #endif
115
116
117 static inline size_t
vdev_mirror_map_size(int children)118 vdev_mirror_map_size(int children)
119 {
120 return (offsetof(mirror_map_t, mm_child[children]) +
121 sizeof(int) * children);
122 }
123
124 static inline mirror_map_t *
vdev_mirror_map_alloc(int children,boolean_t resilvering,boolean_t root)125 vdev_mirror_map_alloc(int children, boolean_t resilvering, boolean_t root)
126 {
127 mirror_map_t *mm;
128
129 mm = kmem_zalloc(vdev_mirror_map_size(children), KM_SLEEP);
130 mm->mm_children = children;
131 mm->mm_resilvering = resilvering;
132 mm->mm_root = root;
133 mm->mm_preferred = (int *)((uintptr_t)mm +
134 offsetof(mirror_map_t, mm_child[children]));
135
136 return mm;
137 }
138
139 static void
vdev_mirror_map_free(zio_t * zio)140 vdev_mirror_map_free(zio_t *zio)
141 {
142 mirror_map_t *mm = zio->io_vsd;
143
144 kmem_free(mm, vdev_mirror_map_size(mm->mm_children));
145 }
146
147 static const zio_vsd_ops_t vdev_mirror_vsd_ops = {
148 vdev_mirror_map_free,
149 zio_vsd_default_cksum_report
150 };
151
152 static int
vdev_mirror_load(mirror_map_t * mm,vdev_t * vd,uint64_t zio_offset)153 vdev_mirror_load(mirror_map_t *mm, vdev_t *vd, uint64_t zio_offset)
154 {
155 uint64_t lastoffset;
156 int load;
157
158 /* All DVAs have equal weight at the root. */
159 if (mm->mm_root)
160 return (INT_MAX);
161
162 /*
163 * We don't return INT_MAX if the device is resilvering i.e.
164 * vdev_resilver_txg != 0 as when tested performance was slightly
165 * worse overall when resilvering with compared to without.
166 */
167
168 /* Standard load based on pending queue length. */
169 load = vdev_queue_length(vd);
170 lastoffset = vdev_queue_lastoffset(vd);
171
172 if (vd->vdev_nonrot) {
173 /* Non-rotating media. */
174 if (lastoffset == zio_offset)
175 return (load + non_rotating_inc);
176
177 /*
178 * Apply a seek penalty even for non-rotating devices as
179 * sequential I/O'a can be aggregated into fewer operations
180 * on the device, thus avoiding unnecessary per-command
181 * overhead and boosting performance.
182 */
183 return (load + non_rotating_seek_inc);
184 }
185
186 /* Rotating media I/O's which directly follow the last I/O. */
187 if (lastoffset == zio_offset)
188 return (load + rotating_inc);
189
190 /*
191 * Apply half the seek increment to I/O's within seek offset
192 * of the last I/O queued to this vdev as they should incure less
193 * of a seek increment.
194 */
195 if (ABS(lastoffset - zio_offset) < rotating_seek_offset)
196 return (load + (rotating_seek_inc / 2));
197
198 /* Apply the full seek increment to all other I/O's. */
199 return (load + rotating_seek_inc);
200 }
201
202
203 static mirror_map_t *
vdev_mirror_map_init(zio_t * zio)204 vdev_mirror_map_init(zio_t *zio)
205 {
206 mirror_map_t *mm = NULL;
207 mirror_child_t *mc;
208 vdev_t *vd = zio->io_vd;
209 int c;
210
211 if (vd == NULL) {
212 dva_t *dva = zio->io_bp->blk_dva;
213 spa_t *spa = zio->io_spa;
214 dva_t dva_copy[SPA_DVAS_PER_BP];
215
216 c = BP_GET_NDVAS(zio->io_bp);
217
218 /*
219 * If we do not trust the pool config, some DVAs might be
220 * invalid or point to vdevs that do not exist. We skip them.
221 */
222 if (!spa_trust_config(spa)) {
223 ASSERT3U(zio->io_type, ==, ZIO_TYPE_READ);
224 int j = 0;
225 for (int i = 0; i < c; i++) {
226 if (zfs_dva_valid(spa, &dva[i], zio->io_bp))
227 dva_copy[j++] = dva[i];
228 }
229 if (j == 0) {
230 zio->io_vsd = NULL;
231 zio->io_error = ENXIO;
232 return (NULL);
233 }
234 if (j < c) {
235 dva = dva_copy;
236 c = j;
237 }
238 }
239
240 mm = vdev_mirror_map_alloc(c, B_FALSE, B_TRUE);
241
242 for (c = 0; c < mm->mm_children; c++) {
243 mc = &mm->mm_child[c];
244 mc->mc_vd = vdev_lookup_top(spa, DVA_GET_VDEV(&dva[c]));
245 mc->mc_offset = DVA_GET_OFFSET(&dva[c]);
246 }
247 } else {
248 /*
249 * If we are resilvering, then we should handle scrub reads
250 * differently; we shouldn't issue them to the resilvering
251 * device because it might not have those blocks.
252 *
253 * We are resilvering iff:
254 * 1) We are a replacing vdev (ie our name is "replacing-1" or
255 * "spare-1" or something like that), and
256 * 2) The pool is currently being resilvered.
257 *
258 * We cannot simply check vd->vdev_resilver_txg, because it's
259 * not set in this path.
260 *
261 * Nor can we just check our vdev_ops; there are cases (such as
262 * when a user types "zpool replace pool odev spare_dev" and
263 * spare_dev is in the spare list, or when a spare device is
264 * automatically used to replace a DEGRADED device) when
265 * resilvering is complete but both the original vdev and the
266 * spare vdev remain in the pool. That behavior is intentional.
267 * It helps implement the policy that a spare should be
268 * automatically removed from the pool after the user replaces
269 * the device that originally failed.
270 *
271 * If a spa load is in progress, then spa_dsl_pool may be
272 * uninitialized. But we shouldn't be resilvering during a spa
273 * load anyway.
274 */
275 boolean_t replacing = (vd->vdev_ops == &vdev_replacing_ops ||
276 vd->vdev_ops == &vdev_spare_ops) &&
277 spa_load_state(vd->vdev_spa) == SPA_LOAD_NONE &&
278 dsl_scan_resilvering(vd->vdev_spa->spa_dsl_pool);
279 mm = vdev_mirror_map_alloc(vd->vdev_children, replacing,
280 B_FALSE);
281 for (c = 0; c < mm->mm_children; c++) {
282 mc = &mm->mm_child[c];
283 mc->mc_vd = vd->vdev_child[c];
284 mc->mc_offset = zio->io_offset;
285 }
286 }
287
288 zio->io_vsd = mm;
289 zio->io_vsd_ops = &vdev_mirror_vsd_ops;
290 return (mm);
291 }
292
293 static int
vdev_mirror_open(vdev_t * vd,uint64_t * asize,uint64_t * max_asize,uint64_t * logical_ashift,uint64_t * physical_ashift)294 vdev_mirror_open(vdev_t *vd, uint64_t *asize, uint64_t *max_asize,
295 uint64_t *logical_ashift, uint64_t *physical_ashift)
296 {
297 int numerrors = 0;
298 int lasterror = 0;
299
300 if (vd->vdev_children == 0) {
301 vd->vdev_stat.vs_aux = VDEV_AUX_BAD_LABEL;
302 return (SET_ERROR(EINVAL));
303 }
304
305 vdev_open_children(vd);
306
307 for (int c = 0; c < vd->vdev_children; c++) {
308 vdev_t *cvd = vd->vdev_child[c];
309
310 if (cvd->vdev_open_error) {
311 lasterror = cvd->vdev_open_error;
312 numerrors++;
313 continue;
314 }
315
316 *asize = MIN(*asize - 1, cvd->vdev_asize - 1) + 1;
317 *max_asize = MIN(*max_asize - 1, cvd->vdev_max_asize - 1) + 1;
318 *logical_ashift = MAX(*logical_ashift, cvd->vdev_ashift);
319 *physical_ashift = MAX(*physical_ashift,
320 cvd->vdev_physical_ashift);
321 }
322
323 if (numerrors == vd->vdev_children) {
324 if (vdev_children_are_offline(vd))
325 vd->vdev_stat.vs_aux = VDEV_AUX_CHILDREN_OFFLINE;
326 else
327 vd->vdev_stat.vs_aux = VDEV_AUX_NO_REPLICAS;
328 return (lasterror);
329 }
330
331 return (0);
332 }
333
334 static void
vdev_mirror_close(vdev_t * vd)335 vdev_mirror_close(vdev_t *vd)
336 {
337 for (int c = 0; c < vd->vdev_children; c++)
338 vdev_close(vd->vdev_child[c]);
339 }
340
341 static void
vdev_mirror_child_done(zio_t * zio)342 vdev_mirror_child_done(zio_t *zio)
343 {
344 mirror_child_t *mc = zio->io_private;
345
346 mc->mc_error = zio->io_error;
347 mc->mc_tried = 1;
348 mc->mc_skipped = 0;
349 }
350
351 static void
vdev_mirror_scrub_done(zio_t * zio)352 vdev_mirror_scrub_done(zio_t *zio)
353 {
354 mirror_child_t *mc = zio->io_private;
355
356 if (zio->io_error == 0) {
357 zio_t *pio;
358 zio_link_t *zl = NULL;
359
360 mutex_enter(&zio->io_lock);
361 while ((pio = zio_walk_parents(zio, &zl)) != NULL) {
362 mutex_enter(&pio->io_lock);
363 ASSERT3U(zio->io_size, >=, pio->io_size);
364 abd_copy(pio->io_abd, zio->io_abd, pio->io_size);
365 mutex_exit(&pio->io_lock);
366 }
367 mutex_exit(&zio->io_lock);
368 }
369 abd_free(zio->io_abd);
370
371 mc->mc_error = zio->io_error;
372 mc->mc_tried = 1;
373 mc->mc_skipped = 0;
374 }
375
376 /*
377 * Check the other, lower-index DVAs to see if they're on the same
378 * vdev as the child we picked. If they are, use them since they
379 * are likely to have been allocated from the primary metaslab in
380 * use at the time, and hence are more likely to have locality with
381 * single-copy data.
382 */
383 static int
vdev_mirror_dva_select(zio_t * zio,int p)384 vdev_mirror_dva_select(zio_t *zio, int p)
385 {
386 dva_t *dva = zio->io_bp->blk_dva;
387 mirror_map_t *mm = zio->io_vsd;
388 int preferred;
389 int c;
390
391 preferred = mm->mm_preferred[p];
392 for (p-- ; p >= 0; p--) {
393 c = mm->mm_preferred[p];
394 if (DVA_GET_VDEV(&dva[c]) == DVA_GET_VDEV(&dva[preferred]))
395 preferred = c;
396 }
397 return (preferred);
398 }
399
400 static int
vdev_mirror_preferred_child_randomize(zio_t * zio)401 vdev_mirror_preferred_child_randomize(zio_t *zio)
402 {
403 mirror_map_t *mm = zio->io_vsd;
404 int p;
405
406 if (mm->mm_root) {
407 p = spa_get_random(mm->mm_preferred_cnt);
408 return (vdev_mirror_dva_select(zio, p));
409 }
410
411 /*
412 * To ensure we don't always favour the first matching vdev,
413 * which could lead to wear leveling issues on SSD's, we
414 * use the I/O offset as a pseudo random seed into the vdevs
415 * which have the lowest load.
416 */
417 p = (zio->io_offset >> vdev_mirror_shift) % mm->mm_preferred_cnt;
418 return (mm->mm_preferred[p]);
419 }
420
421 /*
422 * Try to find a vdev whose DTL doesn't contain the block we want to read
423 * prefering vdevs based on determined load.
424 *
425 * If we can't, try the read on any vdev we haven't already tried.
426 */
427 static int
vdev_mirror_child_select(zio_t * zio)428 vdev_mirror_child_select(zio_t *zio)
429 {
430 mirror_map_t *mm = zio->io_vsd;
431 uint64_t txg = zio->io_txg;
432 int c, lowest_load;
433
434 ASSERT(zio->io_bp == NULL || BP_PHYSICAL_BIRTH(zio->io_bp) == txg);
435
436 lowest_load = INT_MAX;
437 mm->mm_preferred_cnt = 0;
438 for (c = 0; c < mm->mm_children; c++) {
439 mirror_child_t *mc;
440
441 mc = &mm->mm_child[c];
442 if (mc->mc_tried || mc->mc_skipped)
443 continue;
444
445 if (!vdev_readable(mc->mc_vd)) {
446 mc->mc_error = SET_ERROR(ENXIO);
447 mc->mc_tried = 1; /* don't even try */
448 mc->mc_skipped = 1;
449 continue;
450 }
451
452 if (vdev_dtl_contains(mc->mc_vd, DTL_MISSING, txg, 1)) {
453 mc->mc_error = SET_ERROR(ESTALE);
454 mc->mc_skipped = 1;
455 mc->mc_speculative = 1;
456 continue;
457 }
458
459 mc->mc_load = vdev_mirror_load(mm, mc->mc_vd, mc->mc_offset);
460 if (mc->mc_load > lowest_load)
461 continue;
462
463 if (mc->mc_load < lowest_load) {
464 lowest_load = mc->mc_load;
465 mm->mm_preferred_cnt = 0;
466 }
467 mm->mm_preferred[mm->mm_preferred_cnt] = c;
468 mm->mm_preferred_cnt++;
469 }
470
471 if (mm->mm_preferred_cnt == 1) {
472 vdev_queue_register_lastoffset(
473 mm->mm_child[mm->mm_preferred[0]].mc_vd, zio);
474 return (mm->mm_preferred[0]);
475 }
476
477 if (mm->mm_preferred_cnt > 1) {
478 int c = vdev_mirror_preferred_child_randomize(zio);
479
480 vdev_queue_register_lastoffset(mm->mm_child[c].mc_vd, zio);
481 return (c);
482 }
483
484 /*
485 * Every device is either missing or has this txg in its DTL.
486 * Look for any child we haven't already tried before giving up.
487 */
488 for (c = 0; c < mm->mm_children; c++) {
489 if (!mm->mm_child[c].mc_tried) {
490 vdev_queue_register_lastoffset(mm->mm_child[c].mc_vd,
491 zio);
492 return (c);
493 }
494 }
495
496 /*
497 * Every child failed. There's no place left to look.
498 */
499 return (-1);
500 }
501
502 static void
vdev_mirror_io_start(zio_t * zio)503 vdev_mirror_io_start(zio_t *zio)
504 {
505 mirror_map_t *mm;
506 mirror_child_t *mc;
507 int c, children;
508
509 mm = vdev_mirror_map_init(zio);
510
511 if (mm == NULL) {
512 ASSERT(!spa_trust_config(zio->io_spa));
513 ASSERT(zio->io_type == ZIO_TYPE_READ);
514 zio_execute(zio);
515 return;
516 }
517
518 if (zio->io_type == ZIO_TYPE_READ) {
519 if (zio->io_bp != NULL &&
520 (zio->io_flags & ZIO_FLAG_SCRUB) && !mm->mm_resilvering &&
521 mm->mm_children > 1) {
522 /*
523 * For scrubbing reads (if we can verify the
524 * checksum here, as indicated by io_bp being
525 * non-NULL) we need to allocate a read buffer for
526 * each child and issue reads to all children. If
527 * any child succeeds, it will copy its data into
528 * zio->io_data in vdev_mirror_scrub_done.
529 */
530 for (c = 0; c < mm->mm_children; c++) {
531 mc = &mm->mm_child[c];
532 zio_nowait(zio_vdev_child_io(zio, zio->io_bp,
533 mc->mc_vd, mc->mc_offset,
534 abd_alloc_sametype(zio->io_abd,
535 zio->io_size), zio->io_size,
536 zio->io_type, zio->io_priority, 0,
537 vdev_mirror_scrub_done, mc));
538 }
539 zio_execute(zio);
540 return;
541 }
542 /*
543 * For normal reads just pick one child.
544 */
545 c = vdev_mirror_child_select(zio);
546 children = (c >= 0);
547 } else {
548 ASSERT(zio->io_type == ZIO_TYPE_WRITE ||
549 zio->io_type == ZIO_TYPE_FREE);
550
551 /*
552 * Writes and frees go to all children.
553 */
554 c = 0;
555 children = mm->mm_children;
556 }
557
558 while (children--) {
559 mc = &mm->mm_child[c];
560 zio_nowait(zio_vdev_child_io(zio, zio->io_bp,
561 mc->mc_vd, mc->mc_offset, zio->io_abd, zio->io_size,
562 zio->io_type, zio->io_priority, 0,
563 vdev_mirror_child_done, mc));
564 c++;
565 }
566
567 zio_execute(zio);
568 }
569
570 static int
vdev_mirror_worst_error(mirror_map_t * mm)571 vdev_mirror_worst_error(mirror_map_t *mm)
572 {
573 int error[2] = { 0, 0 };
574
575 for (int c = 0; c < mm->mm_children; c++) {
576 mirror_child_t *mc = &mm->mm_child[c];
577 int s = mc->mc_speculative;
578 error[s] = zio_worst_error(error[s], mc->mc_error);
579 }
580
581 return (error[0] ? error[0] : error[1]);
582 }
583
584 static void
vdev_mirror_io_done(zio_t * zio)585 vdev_mirror_io_done(zio_t *zio)
586 {
587 mirror_map_t *mm = zio->io_vsd;
588 mirror_child_t *mc;
589 int c;
590 int good_copies = 0;
591 int unexpected_errors = 0;
592
593 if (mm == NULL)
594 return;
595
596 for (c = 0; c < mm->mm_children; c++) {
597 mc = &mm->mm_child[c];
598
599 if (mc->mc_error) {
600 if (!mc->mc_skipped)
601 unexpected_errors++;
602 } else if (mc->mc_tried) {
603 good_copies++;
604 }
605 }
606
607 if (zio->io_type == ZIO_TYPE_WRITE) {
608 /*
609 * XXX -- for now, treat partial writes as success.
610 *
611 * Now that we support write reallocation, it would be better
612 * to treat partial failure as real failure unless there are
613 * no non-degraded top-level vdevs left, and not update DTLs
614 * if we intend to reallocate.
615 */
616 /* XXPOLICY */
617 if (good_copies != mm->mm_children) {
618 /*
619 * Always require at least one good copy.
620 *
621 * For ditto blocks (io_vd == NULL), require
622 * all copies to be good.
623 *
624 * XXX -- for replacing vdevs, there's no great answer.
625 * If the old device is really dead, we may not even
626 * be able to access it -- so we only want to
627 * require good writes to the new device. But if
628 * the new device turns out to be flaky, we want
629 * to be able to detach it -- which requires all
630 * writes to the old device to have succeeded.
631 */
632 if (good_copies == 0 || zio->io_vd == NULL)
633 zio->io_error = vdev_mirror_worst_error(mm);
634 }
635 return;
636 } else if (zio->io_type == ZIO_TYPE_FREE) {
637 return;
638 }
639
640 ASSERT(zio->io_type == ZIO_TYPE_READ);
641
642 /*
643 * If we don't have a good copy yet, keep trying other children.
644 */
645 /* XXPOLICY */
646 if (good_copies == 0 && (c = vdev_mirror_child_select(zio)) != -1) {
647 ASSERT(c >= 0 && c < mm->mm_children);
648 mc = &mm->mm_child[c];
649 zio_vdev_io_redone(zio);
650 zio_nowait(zio_vdev_child_io(zio, zio->io_bp,
651 mc->mc_vd, mc->mc_offset, zio->io_abd, zio->io_size,
652 ZIO_TYPE_READ, zio->io_priority, 0,
653 vdev_mirror_child_done, mc));
654 return;
655 }
656
657 /* XXPOLICY */
658 if (good_copies == 0) {
659 zio->io_error = vdev_mirror_worst_error(mm);
660 ASSERT(zio->io_error != 0);
661 }
662
663 if (good_copies && spa_writeable(zio->io_spa) &&
664 (unexpected_errors ||
665 (zio->io_flags & ZIO_FLAG_RESILVER) ||
666 ((zio->io_flags & ZIO_FLAG_SCRUB) && mm->mm_resilvering))) {
667 /*
668 * Use the good data we have in hand to repair damaged children.
669 */
670 for (c = 0; c < mm->mm_children; c++) {
671 /*
672 * Don't rewrite known good children.
673 * Not only is it unnecessary, it could
674 * actually be harmful: if the system lost
675 * power while rewriting the only good copy,
676 * there would be no good copies left!
677 */
678 mc = &mm->mm_child[c];
679
680 if (mc->mc_error == 0) {
681 if (mc->mc_tried)
682 continue;
683 /*
684 * We didn't try this child. We need to
685 * repair it if:
686 * 1. it's a scrub (in which case we have
687 * tried everything that was healthy)
688 * - or -
689 * 2. it's an indirect vdev (in which case
690 * it could point to any other vdev, which
691 * might have a bad DTL)
692 * - or -
693 * 3. the DTL indicates that this data is
694 * missing from this vdev
695 */
696 if (!(zio->io_flags & ZIO_FLAG_SCRUB) &&
697 mc->mc_vd->vdev_ops != &vdev_indirect_ops &&
698 !vdev_dtl_contains(mc->mc_vd, DTL_PARTIAL,
699 zio->io_txg, 1))
700 continue;
701 mc->mc_error = SET_ERROR(ESTALE);
702 }
703
704 zio_nowait(zio_vdev_child_io(zio, zio->io_bp,
705 mc->mc_vd, mc->mc_offset,
706 zio->io_abd, zio->io_size,
707 ZIO_TYPE_WRITE, ZIO_PRIORITY_ASYNC_WRITE,
708 ZIO_FLAG_IO_REPAIR | (unexpected_errors ?
709 ZIO_FLAG_SELF_HEAL : 0), NULL, NULL));
710 }
711 }
712 }
713
714 static void
vdev_mirror_state_change(vdev_t * vd,int faulted,int degraded)715 vdev_mirror_state_change(vdev_t *vd, int faulted, int degraded)
716 {
717 if (faulted == vd->vdev_children) {
718 if (vdev_children_are_offline(vd)) {
719 vdev_set_state(vd, B_FALSE, VDEV_STATE_OFFLINE,
720 VDEV_AUX_CHILDREN_OFFLINE);
721 } else {
722 vdev_set_state(vd, B_FALSE, VDEV_STATE_CANT_OPEN,
723 VDEV_AUX_NO_REPLICAS);
724 }
725 } else if (degraded + faulted != 0) {
726 vdev_set_state(vd, B_FALSE, VDEV_STATE_DEGRADED, VDEV_AUX_NONE);
727 } else {
728 vdev_set_state(vd, B_FALSE, VDEV_STATE_HEALTHY, VDEV_AUX_NONE);
729 }
730 }
731
732 vdev_ops_t vdev_mirror_ops = {
733 vdev_mirror_open,
734 vdev_mirror_close,
735 vdev_default_asize,
736 vdev_mirror_io_start,
737 vdev_mirror_io_done,
738 vdev_mirror_state_change,
739 NULL,
740 NULL,
741 NULL,
742 NULL,
743 vdev_default_xlate,
744 VDEV_TYPE_MIRROR, /* name of this vdev type */
745 B_FALSE /* not a leaf vdev */
746 };
747
748 vdev_ops_t vdev_replacing_ops = {
749 vdev_mirror_open,
750 vdev_mirror_close,
751 vdev_default_asize,
752 vdev_mirror_io_start,
753 vdev_mirror_io_done,
754 vdev_mirror_state_change,
755 NULL,
756 NULL,
757 NULL,
758 NULL,
759 vdev_default_xlate,
760 VDEV_TYPE_REPLACING, /* name of this vdev type */
761 B_FALSE /* not a leaf vdev */
762 };
763
764 vdev_ops_t vdev_spare_ops = {
765 vdev_mirror_open,
766 vdev_mirror_close,
767 vdev_default_asize,
768 vdev_mirror_io_start,
769 vdev_mirror_io_done,
770 vdev_mirror_state_change,
771 NULL,
772 NULL,
773 NULL,
774 NULL,
775 vdev_default_xlate,
776 VDEV_TYPE_SPARE, /* name of this vdev type */
777 B_FALSE /* not a leaf vdev */
778 };
779