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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * raid1.c : Multiple Devices driver for Linux
4 *
5 * Copyright (C) 1999, 2000, 2001 Ingo Molnar, Red Hat
6 *
7 * Copyright (C) 1996, 1997, 1998 Ingo Molnar, Miguel de Icaza, Gadi Oxman
8 *
9 * RAID-1 management functions.
10 *
11 * Better read-balancing code written by Mika Kuoppala <miku@iki.fi>, 2000
12 *
13 * Fixes to reconstruction by Jakob Østergaard" <jakob@ostenfeld.dk>
14 * Various fixes by Neil Brown <neilb@cse.unsw.edu.au>
15 *
16 * Changes by Peter T. Breuer <ptb@it.uc3m.es> 31/1/2003 to support
17 * bitmapped intelligence in resync:
18 *
19 * - bitmap marked during normal i/o
20 * - bitmap used to skip nondirty blocks during sync
21 *
22 * Additions to bitmap code, (C) 2003-2004 Paul Clements, SteelEye Technology:
23 * - persistent bitmap code
24 */
25
26#include <linux/slab.h>
27#include <linux/delay.h>
28#include <linux/blkdev.h>
29#include <linux/module.h>
30#include <linux/seq_file.h>
31#include <linux/ratelimit.h>
32
33#include <trace/events/block.h>
34
35#include "md.h"
36#include "raid1.h"
37#include "md-bitmap.h"
38
39#define UNSUPPORTED_MDDEV_FLAGS \
40 ((1L << MD_HAS_JOURNAL) | \
41 (1L << MD_JOURNAL_CLEAN) | \
42 (1L << MD_HAS_PPL) | \
43 (1L << MD_HAS_MULTIPLE_PPLS))
44
45static void allow_barrier(struct r1conf *conf, sector_t sector_nr);
46static void lower_barrier(struct r1conf *conf, sector_t sector_nr);
47
48#define raid1_log(md, fmt, args...) \
49 do { if ((md)->queue) blk_add_trace_msg((md)->queue, "raid1 " fmt, ##args); } while (0)
50
51#include "raid1-10.c"
52
53static int check_and_add_wb(struct md_rdev *rdev, sector_t lo, sector_t hi)
54{
55 struct wb_info *wi, *temp_wi;
56 unsigned long flags;
57 int ret = 0;
58 struct mddev *mddev = rdev->mddev;
59
60 wi = mempool_alloc(mddev->wb_info_pool, GFP_NOIO);
61
62 spin_lock_irqsave(&rdev->wb_list_lock, flags);
63 list_for_each_entry(temp_wi, &rdev->wb_list, list) {
64 /* collision happened */
65 if (hi > temp_wi->lo && lo < temp_wi->hi) {
66 ret = -EBUSY;
67 break;
68 }
69 }
70
71 if (!ret) {
72 wi->lo = lo;
73 wi->hi = hi;
74 list_add(&wi->list, &rdev->wb_list);
75 } else
76 mempool_free(wi, mddev->wb_info_pool);
77 spin_unlock_irqrestore(&rdev->wb_list_lock, flags);
78
79 return ret;
80}
81
82static void remove_wb(struct md_rdev *rdev, sector_t lo, sector_t hi)
83{
84 struct wb_info *wi;
85 unsigned long flags;
86 int found = 0;
87 struct mddev *mddev = rdev->mddev;
88
89 spin_lock_irqsave(&rdev->wb_list_lock, flags);
90 list_for_each_entry(wi, &rdev->wb_list, list)
91 if (hi == wi->hi && lo == wi->lo) {
92 list_del(&wi->list);
93 mempool_free(wi, mddev->wb_info_pool);
94 found = 1;
95 break;
96 }
97
98 if (!found)
99 WARN(1, "The write behind IO is not recorded\n");
100 spin_unlock_irqrestore(&rdev->wb_list_lock, flags);
101 wake_up(&rdev->wb_io_wait);
102}
103
104/*
105 * for resync bio, r1bio pointer can be retrieved from the per-bio
106 * 'struct resync_pages'.
107 */
108static inline struct r1bio *get_resync_r1bio(struct bio *bio)
109{
110 return get_resync_pages(bio)->raid_bio;
111}
112
113static void * r1bio_pool_alloc(gfp_t gfp_flags, void *data)
114{
115 struct pool_info *pi = data;
116 int size = offsetof(struct r1bio, bios[pi->raid_disks]);
117
118 /* allocate a r1bio with room for raid_disks entries in the bios array */
119 return kzalloc(size, gfp_flags);
120}
121
122#define RESYNC_DEPTH 32
123#define RESYNC_SECTORS (RESYNC_BLOCK_SIZE >> 9)
124#define RESYNC_WINDOW (RESYNC_BLOCK_SIZE * RESYNC_DEPTH)
125#define RESYNC_WINDOW_SECTORS (RESYNC_WINDOW >> 9)
126#define CLUSTER_RESYNC_WINDOW (16 * RESYNC_WINDOW)
127#define CLUSTER_RESYNC_WINDOW_SECTORS (CLUSTER_RESYNC_WINDOW >> 9)
128
129static void * r1buf_pool_alloc(gfp_t gfp_flags, void *data)
130{
131 struct pool_info *pi = data;
132 struct r1bio *r1_bio;
133 struct bio *bio;
134 int need_pages;
135 int j;
136 struct resync_pages *rps;
137
138 r1_bio = r1bio_pool_alloc(gfp_flags, pi);
139 if (!r1_bio)
140 return NULL;
141
142 rps = kmalloc_array(pi->raid_disks, sizeof(struct resync_pages),
143 gfp_flags);
144 if (!rps)
145 goto out_free_r1bio;
146
147 /*
148 * Allocate bios : 1 for reading, n-1 for writing
149 */
150 for (j = pi->raid_disks ; j-- ; ) {
151 bio = bio_kmalloc(gfp_flags, RESYNC_PAGES);
152 if (!bio)
153 goto out_free_bio;
154 r1_bio->bios[j] = bio;
155 }
156 /*
157 * Allocate RESYNC_PAGES data pages and attach them to
158 * the first bio.
159 * If this is a user-requested check/repair, allocate
160 * RESYNC_PAGES for each bio.
161 */
162 if (test_bit(MD_RECOVERY_REQUESTED, &pi->mddev->recovery))
163 need_pages = pi->raid_disks;
164 else
165 need_pages = 1;
166 for (j = 0; j < pi->raid_disks; j++) {
167 struct resync_pages *rp = &rps[j];
168
169 bio = r1_bio->bios[j];
170
171 if (j < need_pages) {
172 if (resync_alloc_pages(rp, gfp_flags))
173 goto out_free_pages;
174 } else {
175 memcpy(rp, &rps[0], sizeof(*rp));
176 resync_get_all_pages(rp);
177 }
178
179 rp->raid_bio = r1_bio;
180 bio->bi_private = rp;
181 }
182
183 r1_bio->master_bio = NULL;
184
185 return r1_bio;
186
187out_free_pages:
188 while (--j >= 0)
189 resync_free_pages(&rps[j]);
190
191out_free_bio:
192 while (++j < pi->raid_disks)
193 bio_put(r1_bio->bios[j]);
194 kfree(rps);
195
196out_free_r1bio:
197 rbio_pool_free(r1_bio, data);
198 return NULL;
199}
200
201static void r1buf_pool_free(void *__r1_bio, void *data)
202{
203 struct pool_info *pi = data;
204 int i;
205 struct r1bio *r1bio = __r1_bio;
206 struct resync_pages *rp = NULL;
207
208 for (i = pi->raid_disks; i--; ) {
209 rp = get_resync_pages(r1bio->bios[i]);
210 resync_free_pages(rp);
211 bio_put(r1bio->bios[i]);
212 }
213
214 /* resync pages array stored in the 1st bio's .bi_private */
215 kfree(rp);
216
217 rbio_pool_free(r1bio, data);
218}
219
220static void put_all_bios(struct r1conf *conf, struct r1bio *r1_bio)
221{
222 int i;
223
224 for (i = 0; i < conf->raid_disks * 2; i++) {
225 struct bio **bio = r1_bio->bios + i;
226 if (!BIO_SPECIAL(*bio))
227 bio_put(*bio);
228 *bio = NULL;
229 }
230}
231
232static void free_r1bio(struct r1bio *r1_bio)
233{
234 struct r1conf *conf = r1_bio->mddev->private;
235
236 put_all_bios(conf, r1_bio);
237 mempool_free(r1_bio, &conf->r1bio_pool);
238}
239
240static void put_buf(struct r1bio *r1_bio)
241{
242 struct r1conf *conf = r1_bio->mddev->private;
243 sector_t sect = r1_bio->sector;
244 int i;
245
246 for (i = 0; i < conf->raid_disks * 2; i++) {
247 struct bio *bio = r1_bio->bios[i];
248 if (bio->bi_end_io)
249 rdev_dec_pending(conf->mirrors[i].rdev, r1_bio->mddev);
250 }
251
252 mempool_free(r1_bio, &conf->r1buf_pool);
253
254 lower_barrier(conf, sect);
255}
256
257static void reschedule_retry(struct r1bio *r1_bio)
258{
259 unsigned long flags;
260 struct mddev *mddev = r1_bio->mddev;
261 struct r1conf *conf = mddev->private;
262 int idx;
263
264 idx = sector_to_idx(r1_bio->sector);
265 spin_lock_irqsave(&conf->device_lock, flags);
266 list_add(&r1_bio->retry_list, &conf->retry_list);
267 atomic_inc(&conf->nr_queued[idx]);
268 spin_unlock_irqrestore(&conf->device_lock, flags);
269
270 wake_up(&conf->wait_barrier);
271 md_wakeup_thread(mddev->thread);
272}
273
274/*
275 * raid_end_bio_io() is called when we have finished servicing a mirrored
276 * operation and are ready to return a success/failure code to the buffer
277 * cache layer.
278 */
279static void call_bio_endio(struct r1bio *r1_bio)
280{
281 struct bio *bio = r1_bio->master_bio;
282 struct r1conf *conf = r1_bio->mddev->private;
283
284 if (!test_bit(R1BIO_Uptodate, &r1_bio->state))
285 bio->bi_status = BLK_STS_IOERR;
286
287 bio_endio(bio);
288 /*
289 * Wake up any possible resync thread that waits for the device
290 * to go idle.
291 */
292 allow_barrier(conf, r1_bio->sector);
293}
294
295static void raid_end_bio_io(struct r1bio *r1_bio)
296{
297 struct bio *bio = r1_bio->master_bio;
298
299 /* if nobody has done the final endio yet, do it now */
300 if (!test_and_set_bit(R1BIO_Returned, &r1_bio->state)) {
301 pr_debug("raid1: sync end %s on sectors %llu-%llu\n",
302 (bio_data_dir(bio) == WRITE) ? "write" : "read",
303 (unsigned long long) bio->bi_iter.bi_sector,
304 (unsigned long long) bio_end_sector(bio) - 1);
305
306 call_bio_endio(r1_bio);
307 }
308 free_r1bio(r1_bio);
309}
310
311/*
312 * Update disk head position estimator based on IRQ completion info.
313 */
314static inline void update_head_pos(int disk, struct r1bio *r1_bio)
315{
316 struct r1conf *conf = r1_bio->mddev->private;
317
318 conf->mirrors[disk].head_position =
319 r1_bio->sector + (r1_bio->sectors);
320}
321
322/*
323 * Find the disk number which triggered given bio
324 */
325static int find_bio_disk(struct r1bio *r1_bio, struct bio *bio)
326{
327 int mirror;
328 struct r1conf *conf = r1_bio->mddev->private;
329 int raid_disks = conf->raid_disks;
330
331 for (mirror = 0; mirror < raid_disks * 2; mirror++)
332 if (r1_bio->bios[mirror] == bio)
333 break;
334
335 BUG_ON(mirror == raid_disks * 2);
336 update_head_pos(mirror, r1_bio);
337
338 return mirror;
339}
340
341static void raid1_end_read_request(struct bio *bio)
342{
343 int uptodate = !bio->bi_status;
344 struct r1bio *r1_bio = bio->bi_private;
345 struct r1conf *conf = r1_bio->mddev->private;
346 struct md_rdev *rdev = conf->mirrors[r1_bio->read_disk].rdev;
347
348 /*
349 * this branch is our 'one mirror IO has finished' event handler:
350 */
351 update_head_pos(r1_bio->read_disk, r1_bio);
352
353 if (uptodate)
354 set_bit(R1BIO_Uptodate, &r1_bio->state);
355 else if (test_bit(FailFast, &rdev->flags) &&
356 test_bit(R1BIO_FailFast, &r1_bio->state))
357 /* This was a fail-fast read so we definitely
358 * want to retry */
359 ;
360 else {
361 /* If all other devices have failed, we want to return
362 * the error upwards rather than fail the last device.
363 * Here we redefine "uptodate" to mean "Don't want to retry"
364 */
365 unsigned long flags;
366 spin_lock_irqsave(&conf->device_lock, flags);
367 if (r1_bio->mddev->degraded == conf->raid_disks ||
368 (r1_bio->mddev->degraded == conf->raid_disks-1 &&
369 test_bit(In_sync, &rdev->flags)))
370 uptodate = 1;
371 spin_unlock_irqrestore(&conf->device_lock, flags);
372 }
373
374 if (uptodate) {
375 raid_end_bio_io(r1_bio);
376 rdev_dec_pending(rdev, conf->mddev);
377 } else {
378 /*
379 * oops, read error:
380 */
381 char b[BDEVNAME_SIZE];
382 pr_err_ratelimited("md/raid1:%s: %s: rescheduling sector %llu\n",
383 mdname(conf->mddev),
384 bdevname(rdev->bdev, b),
385 (unsigned long long)r1_bio->sector);
386 set_bit(R1BIO_ReadError, &r1_bio->state);
387 reschedule_retry(r1_bio);
388 /* don't drop the reference on read_disk yet */
389 }
390}
391
392static void close_write(struct r1bio *r1_bio)
393{
394 /* it really is the end of this request */
395 if (test_bit(R1BIO_BehindIO, &r1_bio->state)) {
396 bio_free_pages(r1_bio->behind_master_bio);
397 bio_put(r1_bio->behind_master_bio);
398 r1_bio->behind_master_bio = NULL;
399 }
400 /* clear the bitmap if all writes complete successfully */
401 md_bitmap_endwrite(r1_bio->mddev->bitmap, r1_bio->sector,
402 r1_bio->sectors,
403 !test_bit(R1BIO_Degraded, &r1_bio->state),
404 test_bit(R1BIO_BehindIO, &r1_bio->state));
405 md_write_end(r1_bio->mddev);
406}
407
408static void r1_bio_write_done(struct r1bio *r1_bio)
409{
410 if (!atomic_dec_and_test(&r1_bio->remaining))
411 return;
412
413 if (test_bit(R1BIO_WriteError, &r1_bio->state))
414 reschedule_retry(r1_bio);
415 else {
416 close_write(r1_bio);
417 if (test_bit(R1BIO_MadeGood, &r1_bio->state))
418 reschedule_retry(r1_bio);
419 else
420 raid_end_bio_io(r1_bio);
421 }
422}
423
424static void raid1_end_write_request(struct bio *bio)
425{
426 struct r1bio *r1_bio = bio->bi_private;
427 int behind = test_bit(R1BIO_BehindIO, &r1_bio->state);
428 struct r1conf *conf = r1_bio->mddev->private;
429 struct bio *to_put = NULL;
430 int mirror = find_bio_disk(r1_bio, bio);
431 struct md_rdev *rdev = conf->mirrors[mirror].rdev;
432 bool discard_error;
433
434 discard_error = bio->bi_status && bio_op(bio) == REQ_OP_DISCARD;
435
436 /*
437 * 'one mirror IO has finished' event handler:
438 */
439 if (bio->bi_status && !discard_error) {
440 set_bit(WriteErrorSeen, &rdev->flags);
441 if (!test_and_set_bit(WantReplacement, &rdev->flags))
442 set_bit(MD_RECOVERY_NEEDED, &
443 conf->mddev->recovery);
444
445 if (test_bit(FailFast, &rdev->flags) &&
446 (bio->bi_opf & MD_FAILFAST) &&
447 /* We never try FailFast to WriteMostly devices */
448 !test_bit(WriteMostly, &rdev->flags)) {
449 md_error(r1_bio->mddev, rdev);
450 }
451
452 /*
453 * When the device is faulty, it is not necessary to
454 * handle write error.
455 * For failfast, this is the only remaining device,
456 * We need to retry the write without FailFast.
457 */
458 if (!test_bit(Faulty, &rdev->flags))
459 set_bit(R1BIO_WriteError, &r1_bio->state);
460 else {
461 /* Finished with this branch */
462 r1_bio->bios[mirror] = NULL;
463 to_put = bio;
464 }
465 } else {
466 /*
467 * Set R1BIO_Uptodate in our master bio, so that we
468 * will return a good error code for to the higher
469 * levels even if IO on some other mirrored buffer
470 * fails.
471 *
472 * The 'master' represents the composite IO operation
473 * to user-side. So if something waits for IO, then it
474 * will wait for the 'master' bio.
475 */
476 sector_t first_bad;
477 int bad_sectors;
478
479 r1_bio->bios[mirror] = NULL;
480 to_put = bio;
481 /*
482 * Do not set R1BIO_Uptodate if the current device is
483 * rebuilding or Faulty. This is because we cannot use
484 * such device for properly reading the data back (we could
485 * potentially use it, if the current write would have felt
486 * before rdev->recovery_offset, but for simplicity we don't
487 * check this here.
488 */
489 if (test_bit(In_sync, &rdev->flags) &&
490 !test_bit(Faulty, &rdev->flags))
491 set_bit(R1BIO_Uptodate, &r1_bio->state);
492
493 /* Maybe we can clear some bad blocks. */
494 if (is_badblock(rdev, r1_bio->sector, r1_bio->sectors,
495 &first_bad, &bad_sectors) && !discard_error) {
496 r1_bio->bios[mirror] = IO_MADE_GOOD;
497 set_bit(R1BIO_MadeGood, &r1_bio->state);
498 }
499 }
500
501 if (behind) {
502 if (test_bit(WBCollisionCheck, &rdev->flags)) {
503 sector_t lo = r1_bio->sector;
504 sector_t hi = r1_bio->sector + r1_bio->sectors;
505
506 remove_wb(rdev, lo, hi);
507 }
508 if (test_bit(WriteMostly, &rdev->flags))
509 atomic_dec(&r1_bio->behind_remaining);
510
511 /*
512 * In behind mode, we ACK the master bio once the I/O
513 * has safely reached all non-writemostly
514 * disks. Setting the Returned bit ensures that this
515 * gets done only once -- we don't ever want to return
516 * -EIO here, instead we'll wait
517 */
518 if (atomic_read(&r1_bio->behind_remaining) >= (atomic_read(&r1_bio->remaining)-1) &&
519 test_bit(R1BIO_Uptodate, &r1_bio->state)) {
520 /* Maybe we can return now */
521 if (!test_and_set_bit(R1BIO_Returned, &r1_bio->state)) {
522 struct bio *mbio = r1_bio->master_bio;
523 pr_debug("raid1: behind end write sectors"
524 " %llu-%llu\n",
525 (unsigned long long) mbio->bi_iter.bi_sector,
526 (unsigned long long) bio_end_sector(mbio) - 1);
527 call_bio_endio(r1_bio);
528 }
529 }
530 }
531 if (r1_bio->bios[mirror] == NULL)
532 rdev_dec_pending(rdev, conf->mddev);
533
534 /*
535 * Let's see if all mirrored write operations have finished
536 * already.
537 */
538 r1_bio_write_done(r1_bio);
539
540 if (to_put)
541 bio_put(to_put);
542}
543
544static sector_t align_to_barrier_unit_end(sector_t start_sector,
545 sector_t sectors)
546{
547 sector_t len;
548
549 WARN_ON(sectors == 0);
550 /*
551 * len is the number of sectors from start_sector to end of the
552 * barrier unit which start_sector belongs to.
553 */
554 len = round_up(start_sector + 1, BARRIER_UNIT_SECTOR_SIZE) -
555 start_sector;
556
557 if (len > sectors)
558 len = sectors;
559
560 return len;
561}
562
563/*
564 * This routine returns the disk from which the requested read should
565 * be done. There is a per-array 'next expected sequential IO' sector
566 * number - if this matches on the next IO then we use the last disk.
567 * There is also a per-disk 'last know head position' sector that is
568 * maintained from IRQ contexts, both the normal and the resync IO
569 * completion handlers update this position correctly. If there is no
570 * perfect sequential match then we pick the disk whose head is closest.
571 *
572 * If there are 2 mirrors in the same 2 devices, performance degrades
573 * because position is mirror, not device based.
574 *
575 * The rdev for the device selected will have nr_pending incremented.
576 */
577static int read_balance(struct r1conf *conf, struct r1bio *r1_bio, int *max_sectors)
578{
579 const sector_t this_sector = r1_bio->sector;
580 int sectors;
581 int best_good_sectors;
582 int best_disk, best_dist_disk, best_pending_disk;
583 int has_nonrot_disk;
584 int disk;
585 sector_t best_dist;
586 unsigned int min_pending;
587 struct md_rdev *rdev;
588 int choose_first;
589 int choose_next_idle;
590
591 rcu_read_lock();
592 /*
593 * Check if we can balance. We can balance on the whole
594 * device if no resync is going on, or below the resync window.
595 * We take the first readable disk when above the resync window.
596 */
597 retry:
598 sectors = r1_bio->sectors;
599 best_disk = -1;
600 best_dist_disk = -1;
601 best_dist = MaxSector;
602 best_pending_disk = -1;
603 min_pending = UINT_MAX;
604 best_good_sectors = 0;
605 has_nonrot_disk = 0;
606 choose_next_idle = 0;
607 clear_bit(R1BIO_FailFast, &r1_bio->state);
608
609 if ((conf->mddev->recovery_cp < this_sector + sectors) ||
610 (mddev_is_clustered(conf->mddev) &&
611 md_cluster_ops->area_resyncing(conf->mddev, READ, this_sector,
612 this_sector + sectors)))
613 choose_first = 1;
614 else
615 choose_first = 0;
616
617 for (disk = 0 ; disk < conf->raid_disks * 2 ; disk++) {
618 sector_t dist;
619 sector_t first_bad;
620 int bad_sectors;
621 unsigned int pending;
622 bool nonrot;
623
624 rdev = rcu_dereference(conf->mirrors[disk].rdev);
625 if (r1_bio->bios[disk] == IO_BLOCKED
626 || rdev == NULL
627 || test_bit(Faulty, &rdev->flags))
628 continue;
629 if (!test_bit(In_sync, &rdev->flags) &&
630 rdev->recovery_offset < this_sector + sectors)
631 continue;
632 if (test_bit(WriteMostly, &rdev->flags)) {
633 /* Don't balance among write-mostly, just
634 * use the first as a last resort */
635 if (best_dist_disk < 0) {
636 if (is_badblock(rdev, this_sector, sectors,
637 &first_bad, &bad_sectors)) {
638 if (first_bad <= this_sector)
639 /* Cannot use this */
640 continue;
641 best_good_sectors = first_bad - this_sector;
642 } else
643 best_good_sectors = sectors;
644 best_dist_disk = disk;
645 best_pending_disk = disk;
646 }
647 continue;
648 }
649 /* This is a reasonable device to use. It might
650 * even be best.
651 */
652 if (is_badblock(rdev, this_sector, sectors,
653 &first_bad, &bad_sectors)) {
654 if (best_dist < MaxSector)
655 /* already have a better device */
656 continue;
657 if (first_bad <= this_sector) {
658 /* cannot read here. If this is the 'primary'
659 * device, then we must not read beyond
660 * bad_sectors from another device..
661 */
662 bad_sectors -= (this_sector - first_bad);
663 if (choose_first && sectors > bad_sectors)
664 sectors = bad_sectors;
665 if (best_good_sectors > sectors)
666 best_good_sectors = sectors;
667
668 } else {
669 sector_t good_sectors = first_bad - this_sector;
670 if (good_sectors > best_good_sectors) {
671 best_good_sectors = good_sectors;
672 best_disk = disk;
673 }
674 if (choose_first)
675 break;
676 }
677 continue;
678 } else {
679 if ((sectors > best_good_sectors) && (best_disk >= 0))
680 best_disk = -1;
681 best_good_sectors = sectors;
682 }
683
684 if (best_disk >= 0)
685 /* At least two disks to choose from so failfast is OK */
686 set_bit(R1BIO_FailFast, &r1_bio->state);
687
688 nonrot = blk_queue_nonrot(bdev_get_queue(rdev->bdev));
689 has_nonrot_disk |= nonrot;
690 pending = atomic_read(&rdev->nr_pending);
691 dist = abs(this_sector - conf->mirrors[disk].head_position);
692 if (choose_first) {
693 best_disk = disk;
694 break;
695 }
696 /* Don't change to another disk for sequential reads */
697 if (conf->mirrors[disk].next_seq_sect == this_sector
698 || dist == 0) {
699 int opt_iosize = bdev_io_opt(rdev->bdev) >> 9;
700 struct raid1_info *mirror = &conf->mirrors[disk];
701
702 best_disk = disk;
703 /*
704 * If buffered sequential IO size exceeds optimal
705 * iosize, check if there is idle disk. If yes, choose
706 * the idle disk. read_balance could already choose an
707 * idle disk before noticing it's a sequential IO in
708 * this disk. This doesn't matter because this disk
709 * will idle, next time it will be utilized after the
710 * first disk has IO size exceeds optimal iosize. In
711 * this way, iosize of the first disk will be optimal
712 * iosize at least. iosize of the second disk might be
713 * small, but not a big deal since when the second disk
714 * starts IO, the first disk is likely still busy.
715 */
716 if (nonrot && opt_iosize > 0 &&
717 mirror->seq_start != MaxSector &&
718 mirror->next_seq_sect > opt_iosize &&
719 mirror->next_seq_sect - opt_iosize >=
720 mirror->seq_start) {
721 choose_next_idle = 1;
722 continue;
723 }
724 break;
725 }
726
727 if (choose_next_idle)
728 continue;
729
730 if (min_pending > pending) {
731 min_pending = pending;
732 best_pending_disk = disk;
733 }
734
735 if (dist < best_dist) {
736 best_dist = dist;
737 best_dist_disk = disk;
738 }
739 }
740
741 /*
742 * If all disks are rotational, choose the closest disk. If any disk is
743 * non-rotational, choose the disk with less pending request even the
744 * disk is rotational, which might/might not be optimal for raids with
745 * mixed ratation/non-rotational disks depending on workload.
746 */
747 if (best_disk == -1) {
748 if (has_nonrot_disk || min_pending == 0)
749 best_disk = best_pending_disk;
750 else
751 best_disk = best_dist_disk;
752 }
753
754 if (best_disk >= 0) {
755 rdev = rcu_dereference(conf->mirrors[best_disk].rdev);
756 if (!rdev)
757 goto retry;
758 atomic_inc(&rdev->nr_pending);
759 sectors = best_good_sectors;
760
761 if (conf->mirrors[best_disk].next_seq_sect != this_sector)
762 conf->mirrors[best_disk].seq_start = this_sector;
763
764 conf->mirrors[best_disk].next_seq_sect = this_sector + sectors;
765 }
766 rcu_read_unlock();
767 *max_sectors = sectors;
768
769 return best_disk;
770}
771
772static int raid1_congested(struct mddev *mddev, int bits)
773{
774 struct r1conf *conf = mddev->private;
775 int i, ret = 0;
776
777 if ((bits & (1 << WB_async_congested)) &&
778 conf->pending_count >= max_queued_requests)
779 return 1;
780
781 rcu_read_lock();
782 for (i = 0; i < conf->raid_disks * 2; i++) {
783 struct md_rdev *rdev = rcu_dereference(conf->mirrors[i].rdev);
784 if (rdev && !test_bit(Faulty, &rdev->flags)) {
785 struct request_queue *q = bdev_get_queue(rdev->bdev);
786
787 BUG_ON(!q);
788
789 /* Note the '|| 1' - when read_balance prefers
790 * non-congested targets, it can be removed
791 */
792 if ((bits & (1 << WB_async_congested)) || 1)
793 ret |= bdi_congested(q->backing_dev_info, bits);
794 else
795 ret &= bdi_congested(q->backing_dev_info, bits);
796 }
797 }
798 rcu_read_unlock();
799 return ret;
800}
801
802static void flush_bio_list(struct r1conf *conf, struct bio *bio)
803{
804 /* flush any pending bitmap writes to disk before proceeding w/ I/O */
805 md_bitmap_unplug(conf->mddev->bitmap);
806 wake_up(&conf->wait_barrier);
807
808 while (bio) { /* submit pending writes */
809 struct bio *next = bio->bi_next;
810 struct md_rdev *rdev = (void *)bio->bi_disk;
811 bio->bi_next = NULL;
812 bio_set_dev(bio, rdev->bdev);
813 if (test_bit(Faulty, &rdev->flags)) {
814 bio_io_error(bio);
815 } else if (unlikely((bio_op(bio) == REQ_OP_DISCARD) &&
816 !blk_queue_discard(bio->bi_disk->queue)))
817 /* Just ignore it */
818 bio_endio(bio);
819 else
820 generic_make_request(bio);
821 bio = next;
822 }
823}
824
825static void flush_pending_writes(struct r1conf *conf)
826{
827 /* Any writes that have been queued but are awaiting
828 * bitmap updates get flushed here.
829 */
830 spin_lock_irq(&conf->device_lock);
831
832 if (conf->pending_bio_list.head) {
833 struct blk_plug plug;
834 struct bio *bio;
835
836 bio = bio_list_get(&conf->pending_bio_list);
837 conf->pending_count = 0;
838 spin_unlock_irq(&conf->device_lock);
839
840 /*
841 * As this is called in a wait_event() loop (see freeze_array),
842 * current->state might be TASK_UNINTERRUPTIBLE which will
843 * cause a warning when we prepare to wait again. As it is
844 * rare that this path is taken, it is perfectly safe to force
845 * us to go around the wait_event() loop again, so the warning
846 * is a false-positive. Silence the warning by resetting
847 * thread state
848 */
849 __set_current_state(TASK_RUNNING);
850 blk_start_plug(&plug);
851 flush_bio_list(conf, bio);
852 blk_finish_plug(&plug);
853 } else
854 spin_unlock_irq(&conf->device_lock);
855}
856
857/* Barriers....
858 * Sometimes we need to suspend IO while we do something else,
859 * either some resync/recovery, or reconfigure the array.
860 * To do this we raise a 'barrier'.
861 * The 'barrier' is a counter that can be raised multiple times
862 * to count how many activities are happening which preclude
863 * normal IO.
864 * We can only raise the barrier if there is no pending IO.
865 * i.e. if nr_pending == 0.
866 * We choose only to raise the barrier if no-one is waiting for the
867 * barrier to go down. This means that as soon as an IO request
868 * is ready, no other operations which require a barrier will start
869 * until the IO request has had a chance.
870 *
871 * So: regular IO calls 'wait_barrier'. When that returns there
872 * is no backgroup IO happening, It must arrange to call
873 * allow_barrier when it has finished its IO.
874 * backgroup IO calls must call raise_barrier. Once that returns
875 * there is no normal IO happeing. It must arrange to call
876 * lower_barrier when the particular background IO completes.
877 *
878 * If resync/recovery is interrupted, returns -EINTR;
879 * Otherwise, returns 0.
880 */
881static int raise_barrier(struct r1conf *conf, sector_t sector_nr)
882{
883 int idx = sector_to_idx(sector_nr);
884
885 spin_lock_irq(&conf->resync_lock);
886
887 /* Wait until no block IO is waiting */
888 wait_event_lock_irq(conf->wait_barrier,
889 !atomic_read(&conf->nr_waiting[idx]),
890 conf->resync_lock);
891
892 /* block any new IO from starting */
893 atomic_inc(&conf->barrier[idx]);
894 /*
895 * In raise_barrier() we firstly increase conf->barrier[idx] then
896 * check conf->nr_pending[idx]. In _wait_barrier() we firstly
897 * increase conf->nr_pending[idx] then check conf->barrier[idx].
898 * A memory barrier here to make sure conf->nr_pending[idx] won't
899 * be fetched before conf->barrier[idx] is increased. Otherwise
900 * there will be a race between raise_barrier() and _wait_barrier().
901 */
902 smp_mb__after_atomic();
903
904 /* For these conditions we must wait:
905 * A: while the array is in frozen state
906 * B: while conf->nr_pending[idx] is not 0, meaning regular I/O
907 * existing in corresponding I/O barrier bucket.
908 * C: while conf->barrier[idx] >= RESYNC_DEPTH, meaning reaches
909 * max resync count which allowed on current I/O barrier bucket.
910 */
911 wait_event_lock_irq(conf->wait_barrier,
912 (!conf->array_frozen &&
913 !atomic_read(&conf->nr_pending[idx]) &&
914 atomic_read(&conf->barrier[idx]) < RESYNC_DEPTH) ||
915 test_bit(MD_RECOVERY_INTR, &conf->mddev->recovery),
916 conf->resync_lock);
917
918 if (test_bit(MD_RECOVERY_INTR, &conf->mddev->recovery)) {
919 atomic_dec(&conf->barrier[idx]);
920 spin_unlock_irq(&conf->resync_lock);
921 wake_up(&conf->wait_barrier);
922 return -EINTR;
923 }
924
925 atomic_inc(&conf->nr_sync_pending);
926 spin_unlock_irq(&conf->resync_lock);
927
928 return 0;
929}
930
931static void lower_barrier(struct r1conf *conf, sector_t sector_nr)
932{
933 int idx = sector_to_idx(sector_nr);
934
935 BUG_ON(atomic_read(&conf->barrier[idx]) <= 0);
936
937 atomic_dec(&conf->barrier[idx]);
938 atomic_dec(&conf->nr_sync_pending);
939 wake_up(&conf->wait_barrier);
940}
941
942static void _wait_barrier(struct r1conf *conf, int idx)
943{
944 /*
945 * We need to increase conf->nr_pending[idx] very early here,
946 * then raise_barrier() can be blocked when it waits for
947 * conf->nr_pending[idx] to be 0. Then we can avoid holding
948 * conf->resync_lock when there is no barrier raised in same
949 * barrier unit bucket. Also if the array is frozen, I/O
950 * should be blocked until array is unfrozen.
951 */
952 atomic_inc(&conf->nr_pending[idx]);
953 /*
954 * In _wait_barrier() we firstly increase conf->nr_pending[idx], then
955 * check conf->barrier[idx]. In raise_barrier() we firstly increase
956 * conf->barrier[idx], then check conf->nr_pending[idx]. A memory
957 * barrier is necessary here to make sure conf->barrier[idx] won't be
958 * fetched before conf->nr_pending[idx] is increased. Otherwise there
959 * will be a race between _wait_barrier() and raise_barrier().
960 */
961 smp_mb__after_atomic();
962
963 /*
964 * Don't worry about checking two atomic_t variables at same time
965 * here. If during we check conf->barrier[idx], the array is
966 * frozen (conf->array_frozen is 1), and chonf->barrier[idx] is
967 * 0, it is safe to return and make the I/O continue. Because the
968 * array is frozen, all I/O returned here will eventually complete
969 * or be queued, no race will happen. See code comment in
970 * frozen_array().
971 */
972 if (!READ_ONCE(conf->array_frozen) &&
973 !atomic_read(&conf->barrier[idx]))
974 return;
975
976 /*
977 * After holding conf->resync_lock, conf->nr_pending[idx]
978 * should be decreased before waiting for barrier to drop.
979 * Otherwise, we may encounter a race condition because
980 * raise_barrer() might be waiting for conf->nr_pending[idx]
981 * to be 0 at same time.
982 */
983 spin_lock_irq(&conf->resync_lock);
984 atomic_inc(&conf->nr_waiting[idx]);
985 atomic_dec(&conf->nr_pending[idx]);
986 /*
987 * In case freeze_array() is waiting for
988 * get_unqueued_pending() == extra
989 */
990 wake_up(&conf->wait_barrier);
991 /* Wait for the barrier in same barrier unit bucket to drop. */
992 wait_event_lock_irq(conf->wait_barrier,
993 !conf->array_frozen &&
994 !atomic_read(&conf->barrier[idx]),
995 conf->resync_lock);
996 atomic_inc(&conf->nr_pending[idx]);
997 atomic_dec(&conf->nr_waiting[idx]);
998 spin_unlock_irq(&conf->resync_lock);
999}
1000
1001static void wait_read_barrier(struct r1conf *conf, sector_t sector_nr)
1002{
1003 int idx = sector_to_idx(sector_nr);
1004
1005 /*
1006 * Very similar to _wait_barrier(). The difference is, for read
1007 * I/O we don't need wait for sync I/O, but if the whole array
1008 * is frozen, the read I/O still has to wait until the array is
1009 * unfrozen. Since there is no ordering requirement with
1010 * conf->barrier[idx] here, memory barrier is unnecessary as well.
1011 */
1012 atomic_inc(&conf->nr_pending[idx]);
1013
1014 if (!READ_ONCE(conf->array_frozen))
1015 return;
1016
1017 spin_lock_irq(&conf->resync_lock);
1018 atomic_inc(&conf->nr_waiting[idx]);
1019 atomic_dec(&conf->nr_pending[idx]);
1020 /*
1021 * In case freeze_array() is waiting for
1022 * get_unqueued_pending() == extra
1023 */
1024 wake_up(&conf->wait_barrier);
1025 /* Wait for array to be unfrozen */
1026 wait_event_lock_irq(conf->wait_barrier,
1027 !conf->array_frozen,
1028 conf->resync_lock);
1029 atomic_inc(&conf->nr_pending[idx]);
1030 atomic_dec(&conf->nr_waiting[idx]);
1031 spin_unlock_irq(&conf->resync_lock);
1032}
1033
1034static void wait_barrier(struct r1conf *conf, sector_t sector_nr)
1035{
1036 int idx = sector_to_idx(sector_nr);
1037
1038 _wait_barrier(conf, idx);
1039}
1040
1041static void _allow_barrier(struct r1conf *conf, int idx)
1042{
1043 atomic_dec(&conf->nr_pending[idx]);
1044 wake_up(&conf->wait_barrier);
1045}
1046
1047static void allow_barrier(struct r1conf *conf, sector_t sector_nr)
1048{
1049 int idx = sector_to_idx(sector_nr);
1050
1051 _allow_barrier(conf, idx);
1052}
1053
1054/* conf->resync_lock should be held */
1055static int get_unqueued_pending(struct r1conf *conf)
1056{
1057 int idx, ret;
1058
1059 ret = atomic_read(&conf->nr_sync_pending);
1060 for (idx = 0; idx < BARRIER_BUCKETS_NR; idx++)
1061 ret += atomic_read(&conf->nr_pending[idx]) -
1062 atomic_read(&conf->nr_queued[idx]);
1063
1064 return ret;
1065}
1066
1067static void freeze_array(struct r1conf *conf, int extra)
1068{
1069 /* Stop sync I/O and normal I/O and wait for everything to
1070 * go quiet.
1071 * This is called in two situations:
1072 * 1) management command handlers (reshape, remove disk, quiesce).
1073 * 2) one normal I/O request failed.
1074
1075 * After array_frozen is set to 1, new sync IO will be blocked at
1076 * raise_barrier(), and new normal I/O will blocked at _wait_barrier()
1077 * or wait_read_barrier(). The flying I/Os will either complete or be
1078 * queued. When everything goes quite, there are only queued I/Os left.
1079
1080 * Every flying I/O contributes to a conf->nr_pending[idx], idx is the
1081 * barrier bucket index which this I/O request hits. When all sync and
1082 * normal I/O are queued, sum of all conf->nr_pending[] will match sum
1083 * of all conf->nr_queued[]. But normal I/O failure is an exception,
1084 * in handle_read_error(), we may call freeze_array() before trying to
1085 * fix the read error. In this case, the error read I/O is not queued,
1086 * so get_unqueued_pending() == 1.
1087 *
1088 * Therefore before this function returns, we need to wait until
1089 * get_unqueued_pendings(conf) gets equal to extra. For
1090 * normal I/O context, extra is 1, in rested situations extra is 0.
1091 */
1092 spin_lock_irq(&conf->resync_lock);
1093 conf->array_frozen = 1;
1094 raid1_log(conf->mddev, "wait freeze");
1095 wait_event_lock_irq_cmd(
1096 conf->wait_barrier,
1097 get_unqueued_pending(conf) == extra,
1098 conf->resync_lock,
1099 flush_pending_writes(conf));
1100 spin_unlock_irq(&conf->resync_lock);
1101}
1102static void unfreeze_array(struct r1conf *conf)
1103{
1104 /* reverse the effect of the freeze */
1105 spin_lock_irq(&conf->resync_lock);
1106 conf->array_frozen = 0;
1107 spin_unlock_irq(&conf->resync_lock);
1108 wake_up(&conf->wait_barrier);
1109}
1110
1111static void alloc_behind_master_bio(struct r1bio *r1_bio,
1112 struct bio *bio)
1113{
1114 int size = bio->bi_iter.bi_size;
1115 unsigned vcnt = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
1116 int i = 0;
1117 struct bio *behind_bio = NULL;
1118
1119 behind_bio = bio_alloc_mddev(GFP_NOIO, vcnt, r1_bio->mddev);
1120 if (!behind_bio)
1121 return;
1122
1123 /* discard op, we don't support writezero/writesame yet */
1124 if (!bio_has_data(bio)) {
1125 behind_bio->bi_iter.bi_size = size;
1126 goto skip_copy;
1127 }
1128
1129 behind_bio->bi_write_hint = bio->bi_write_hint;
1130
1131 while (i < vcnt && size) {
1132 struct page *page;
1133 int len = min_t(int, PAGE_SIZE, size);
1134
1135 page = alloc_page(GFP_NOIO);
1136 if (unlikely(!page))
1137 goto free_pages;
1138
1139 bio_add_page(behind_bio, page, len, 0);
1140
1141 size -= len;
1142 i++;
1143 }
1144
1145 bio_copy_data(behind_bio, bio);
1146skip_copy:
1147 r1_bio->behind_master_bio = behind_bio;
1148 set_bit(R1BIO_BehindIO, &r1_bio->state);
1149
1150 return;
1151
1152free_pages:
1153 pr_debug("%dB behind alloc failed, doing sync I/O\n",
1154 bio->bi_iter.bi_size);
1155 bio_free_pages(behind_bio);
1156 bio_put(behind_bio);
1157}
1158
1159struct raid1_plug_cb {
1160 struct blk_plug_cb cb;
1161 struct bio_list pending;
1162 int pending_cnt;
1163};
1164
1165static void raid1_unplug(struct blk_plug_cb *cb, bool from_schedule)
1166{
1167 struct raid1_plug_cb *plug = container_of(cb, struct raid1_plug_cb,
1168 cb);
1169 struct mddev *mddev = plug->cb.data;
1170 struct r1conf *conf = mddev->private;
1171 struct bio *bio;
1172
1173 if (from_schedule || current->bio_list) {
1174 spin_lock_irq(&conf->device_lock);
1175 bio_list_merge(&conf->pending_bio_list, &plug->pending);
1176 conf->pending_count += plug->pending_cnt;
1177 spin_unlock_irq(&conf->device_lock);
1178 wake_up(&conf->wait_barrier);
1179 md_wakeup_thread(mddev->thread);
1180 kfree(plug);
1181 return;
1182 }
1183
1184 /* we aren't scheduling, so we can do the write-out directly. */
1185 bio = bio_list_get(&plug->pending);
1186 flush_bio_list(conf, bio);
1187 kfree(plug);
1188}
1189
1190static void init_r1bio(struct r1bio *r1_bio, struct mddev *mddev, struct bio *bio)
1191{
1192 r1_bio->master_bio = bio;
1193 r1_bio->sectors = bio_sectors(bio);
1194 r1_bio->state = 0;
1195 r1_bio->mddev = mddev;
1196 r1_bio->sector = bio->bi_iter.bi_sector;
1197}
1198
1199static inline struct r1bio *
1200alloc_r1bio(struct mddev *mddev, struct bio *bio)
1201{
1202 struct r1conf *conf = mddev->private;
1203 struct r1bio *r1_bio;
1204
1205 r1_bio = mempool_alloc(&conf->r1bio_pool, GFP_NOIO);
1206 /* Ensure no bio records IO_BLOCKED */
1207 memset(r1_bio->bios, 0, conf->raid_disks * sizeof(r1_bio->bios[0]));
1208 init_r1bio(r1_bio, mddev, bio);
1209 return r1_bio;
1210}
1211
1212static void raid1_read_request(struct mddev *mddev, struct bio *bio,
1213 int max_read_sectors, struct r1bio *r1_bio)
1214{
1215 struct r1conf *conf = mddev->private;
1216 struct raid1_info *mirror;
1217 struct bio *read_bio;
1218 struct bitmap *bitmap = mddev->bitmap;
1219 const int op = bio_op(bio);
1220 const unsigned long do_sync = (bio->bi_opf & REQ_SYNC);
1221 int max_sectors;
1222 int rdisk;
1223 bool print_msg = !!r1_bio;
1224 char b[BDEVNAME_SIZE];
1225
1226 /*
1227 * If r1_bio is set, we are blocking the raid1d thread
1228 * so there is a tiny risk of deadlock. So ask for
1229 * emergency memory if needed.
1230 */
1231 gfp_t gfp = r1_bio ? (GFP_NOIO | __GFP_HIGH) : GFP_NOIO;
1232
1233 if (print_msg) {
1234 /* Need to get the block device name carefully */
1235 struct md_rdev *rdev;
1236 rcu_read_lock();
1237 rdev = rcu_dereference(conf->mirrors[r1_bio->read_disk].rdev);
1238 if (rdev)
1239 bdevname(rdev->bdev, b);
1240 else
1241 strcpy(b, "???");
1242 rcu_read_unlock();
1243 }
1244
1245 /*
1246 * Still need barrier for READ in case that whole
1247 * array is frozen.
1248 */
1249 wait_read_barrier(conf, bio->bi_iter.bi_sector);
1250
1251 if (!r1_bio)
1252 r1_bio = alloc_r1bio(mddev, bio);
1253 else
1254 init_r1bio(r1_bio, mddev, bio);
1255 r1_bio->sectors = max_read_sectors;
1256
1257 /*
1258 * make_request() can abort the operation when read-ahead is being
1259 * used and no empty request is available.
1260 */
1261 rdisk = read_balance(conf, r1_bio, &max_sectors);
1262
1263 if (rdisk < 0) {
1264 /* couldn't find anywhere to read from */
1265 if (print_msg) {
1266 pr_crit_ratelimited("md/raid1:%s: %s: unrecoverable I/O read error for block %llu\n",
1267 mdname(mddev),
1268 b,
1269 (unsigned long long)r1_bio->sector);
1270 }
1271 raid_end_bio_io(r1_bio);
1272 return;
1273 }
1274 mirror = conf->mirrors + rdisk;
1275
1276 if (print_msg)
1277 pr_info_ratelimited("md/raid1:%s: redirecting sector %llu to other mirror: %s\n",
1278 mdname(mddev),
1279 (unsigned long long)r1_bio->sector,
1280 bdevname(mirror->rdev->bdev, b));
1281
1282 if (test_bit(WriteMostly, &mirror->rdev->flags) &&
1283 bitmap) {
1284 /*
1285 * Reading from a write-mostly device must take care not to
1286 * over-take any writes that are 'behind'
1287 */
1288 raid1_log(mddev, "wait behind writes");
1289 wait_event(bitmap->behind_wait,
1290 atomic_read(&bitmap->behind_writes) == 0);
1291 }
1292
1293 if (max_sectors < bio_sectors(bio)) {
1294 struct bio *split = bio_split(bio, max_sectors,
1295 gfp, &conf->bio_split);
1296 bio_chain(split, bio);
1297 generic_make_request(bio);
1298 bio = split;
1299 r1_bio->master_bio = bio;
1300 r1_bio->sectors = max_sectors;
1301 }
1302
1303 r1_bio->read_disk = rdisk;
1304
1305 read_bio = bio_clone_fast(bio, gfp, &mddev->bio_set);
1306
1307 r1_bio->bios[rdisk] = read_bio;
1308
1309 read_bio->bi_iter.bi_sector = r1_bio->sector +
1310 mirror->rdev->data_offset;
1311 bio_set_dev(read_bio, mirror->rdev->bdev);
1312 read_bio->bi_end_io = raid1_end_read_request;
1313 bio_set_op_attrs(read_bio, op, do_sync);
1314 if (test_bit(FailFast, &mirror->rdev->flags) &&
1315 test_bit(R1BIO_FailFast, &r1_bio->state))
1316 read_bio->bi_opf |= MD_FAILFAST;
1317 read_bio->bi_private = r1_bio;
1318
1319 if (mddev->gendisk)
1320 trace_block_bio_remap(read_bio->bi_disk->queue, read_bio,
1321 disk_devt(mddev->gendisk), r1_bio->sector);
1322
1323 generic_make_request(read_bio);
1324}
1325
1326static void raid1_write_request(struct mddev *mddev, struct bio *bio,
1327 int max_write_sectors)
1328{
1329 struct r1conf *conf = mddev->private;
1330 struct r1bio *r1_bio;
1331 int i, disks;
1332 struct bitmap *bitmap = mddev->bitmap;
1333 unsigned long flags;
1334 struct md_rdev *blocked_rdev;
1335 struct blk_plug_cb *cb;
1336 struct raid1_plug_cb *plug = NULL;
1337 int first_clone;
1338 int max_sectors;
1339
1340 if (mddev_is_clustered(mddev) &&
1341 md_cluster_ops->area_resyncing(mddev, WRITE,
1342 bio->bi_iter.bi_sector, bio_end_sector(bio))) {
1343
1344 DEFINE_WAIT(w);
1345 for (;;) {
1346 prepare_to_wait(&conf->wait_barrier,
1347 &w, TASK_IDLE);
1348 if (!md_cluster_ops->area_resyncing(mddev, WRITE,
1349 bio->bi_iter.bi_sector,
1350 bio_end_sector(bio)))
1351 break;
1352 schedule();
1353 }
1354 finish_wait(&conf->wait_barrier, &w);
1355 }
1356
1357 /*
1358 * Register the new request and wait if the reconstruction
1359 * thread has put up a bar for new requests.
1360 * Continue immediately if no resync is active currently.
1361 */
1362 wait_barrier(conf, bio->bi_iter.bi_sector);
1363
1364 r1_bio = alloc_r1bio(mddev, bio);
1365 r1_bio->sectors = max_write_sectors;
1366
1367 if (conf->pending_count >= max_queued_requests) {
1368 md_wakeup_thread(mddev->thread);
1369 raid1_log(mddev, "wait queued");
1370 wait_event(conf->wait_barrier,
1371 conf->pending_count < max_queued_requests);
1372 }
1373 /* first select target devices under rcu_lock and
1374 * inc refcount on their rdev. Record them by setting
1375 * bios[x] to bio
1376 * If there are known/acknowledged bad blocks on any device on
1377 * which we have seen a write error, we want to avoid writing those
1378 * blocks.
1379 * This potentially requires several writes to write around
1380 * the bad blocks. Each set of writes gets it's own r1bio
1381 * with a set of bios attached.
1382 */
1383
1384 disks = conf->raid_disks * 2;
1385 retry_write:
1386 blocked_rdev = NULL;
1387 rcu_read_lock();
1388 max_sectors = r1_bio->sectors;
1389 for (i = 0; i < disks; i++) {
1390 struct md_rdev *rdev = rcu_dereference(conf->mirrors[i].rdev);
1391 if (rdev && unlikely(test_bit(Blocked, &rdev->flags))) {
1392 atomic_inc(&rdev->nr_pending);
1393 blocked_rdev = rdev;
1394 break;
1395 }
1396 r1_bio->bios[i] = NULL;
1397 if (!rdev || test_bit(Faulty, &rdev->flags)) {
1398 if (i < conf->raid_disks)
1399 set_bit(R1BIO_Degraded, &r1_bio->state);
1400 continue;
1401 }
1402
1403 atomic_inc(&rdev->nr_pending);
1404 if (test_bit(WriteErrorSeen, &rdev->flags)) {
1405 sector_t first_bad;
1406 int bad_sectors;
1407 int is_bad;
1408
1409 is_bad = is_badblock(rdev, r1_bio->sector, max_sectors,
1410 &first_bad, &bad_sectors);
1411 if (is_bad < 0) {
1412 /* mustn't write here until the bad block is
1413 * acknowledged*/
1414 set_bit(BlockedBadBlocks, &rdev->flags);
1415 blocked_rdev = rdev;
1416 break;
1417 }
1418 if (is_bad && first_bad <= r1_bio->sector) {
1419 /* Cannot write here at all */
1420 bad_sectors -= (r1_bio->sector - first_bad);
1421 if (bad_sectors < max_sectors)
1422 /* mustn't write more than bad_sectors
1423 * to other devices yet
1424 */
1425 max_sectors = bad_sectors;
1426 rdev_dec_pending(rdev, mddev);
1427 /* We don't set R1BIO_Degraded as that
1428 * only applies if the disk is
1429 * missing, so it might be re-added,
1430 * and we want to know to recover this
1431 * chunk.
1432 * In this case the device is here,
1433 * and the fact that this chunk is not
1434 * in-sync is recorded in the bad
1435 * block log
1436 */
1437 continue;
1438 }
1439 if (is_bad) {
1440 int good_sectors = first_bad - r1_bio->sector;
1441 if (good_sectors < max_sectors)
1442 max_sectors = good_sectors;
1443 }
1444 }
1445 r1_bio->bios[i] = bio;
1446 }
1447 rcu_read_unlock();
1448
1449 if (unlikely(blocked_rdev)) {
1450 /* Wait for this device to become unblocked */
1451 int j;
1452
1453 for (j = 0; j < i; j++)
1454 if (r1_bio->bios[j])
1455 rdev_dec_pending(conf->mirrors[j].rdev, mddev);
1456 r1_bio->state = 0;
1457 allow_barrier(conf, bio->bi_iter.bi_sector);
1458 raid1_log(mddev, "wait rdev %d blocked", blocked_rdev->raid_disk);
1459 md_wait_for_blocked_rdev(blocked_rdev, mddev);
1460 wait_barrier(conf, bio->bi_iter.bi_sector);
1461 goto retry_write;
1462 }
1463
1464 if (max_sectors < bio_sectors(bio)) {
1465 struct bio *split = bio_split(bio, max_sectors,
1466 GFP_NOIO, &conf->bio_split);
1467 bio_chain(split, bio);
1468 generic_make_request(bio);
1469 bio = split;
1470 r1_bio->master_bio = bio;
1471 r1_bio->sectors = max_sectors;
1472 }
1473
1474 atomic_set(&r1_bio->remaining, 1);
1475 atomic_set(&r1_bio->behind_remaining, 0);
1476
1477 first_clone = 1;
1478
1479 for (i = 0; i < disks; i++) {
1480 struct bio *mbio = NULL;
1481 if (!r1_bio->bios[i])
1482 continue;
1483
1484 if (first_clone) {
1485 /* do behind I/O ?
1486 * Not if there are too many, or cannot
1487 * allocate memory, or a reader on WriteMostly
1488 * is waiting for behind writes to flush */
1489 if (bitmap &&
1490 (atomic_read(&bitmap->behind_writes)
1491 < mddev->bitmap_info.max_write_behind) &&
1492 !waitqueue_active(&bitmap->behind_wait)) {
1493 alloc_behind_master_bio(r1_bio, bio);
1494 }
1495
1496 md_bitmap_startwrite(bitmap, r1_bio->sector, r1_bio->sectors,
1497 test_bit(R1BIO_BehindIO, &r1_bio->state));
1498 first_clone = 0;
1499 }
1500
1501 if (r1_bio->behind_master_bio)
1502 mbio = bio_clone_fast(r1_bio->behind_master_bio,
1503 GFP_NOIO, &mddev->bio_set);
1504 else
1505 mbio = bio_clone_fast(bio, GFP_NOIO, &mddev->bio_set);
1506
1507 if (r1_bio->behind_master_bio) {
1508 struct md_rdev *rdev = conf->mirrors[i].rdev;
1509
1510 if (test_bit(WBCollisionCheck, &rdev->flags)) {
1511 sector_t lo = r1_bio->sector;
1512 sector_t hi = r1_bio->sector + r1_bio->sectors;
1513
1514 wait_event(rdev->wb_io_wait,
1515 check_and_add_wb(rdev, lo, hi) == 0);
1516 }
1517 if (test_bit(WriteMostly, &rdev->flags))
1518 atomic_inc(&r1_bio->behind_remaining);
1519 }
1520
1521 r1_bio->bios[i] = mbio;
1522
1523 mbio->bi_iter.bi_sector = (r1_bio->sector +
1524 conf->mirrors[i].rdev->data_offset);
1525 bio_set_dev(mbio, conf->mirrors[i].rdev->bdev);
1526 mbio->bi_end_io = raid1_end_write_request;
1527 mbio->bi_opf = bio_op(bio) | (bio->bi_opf & (REQ_SYNC | REQ_FUA));
1528 if (test_bit(FailFast, &conf->mirrors[i].rdev->flags) &&
1529 !test_bit(WriteMostly, &conf->mirrors[i].rdev->flags) &&
1530 conf->raid_disks - mddev->degraded > 1)
1531 mbio->bi_opf |= MD_FAILFAST;
1532 mbio->bi_private = r1_bio;
1533
1534 atomic_inc(&r1_bio->remaining);
1535
1536 if (mddev->gendisk)
1537 trace_block_bio_remap(mbio->bi_disk->queue,
1538 mbio, disk_devt(mddev->gendisk),
1539 r1_bio->sector);
1540 /* flush_pending_writes() needs access to the rdev so...*/
1541 mbio->bi_disk = (void *)conf->mirrors[i].rdev;
1542
1543 cb = blk_check_plugged(raid1_unplug, mddev, sizeof(*plug));
1544 if (cb)
1545 plug = container_of(cb, struct raid1_plug_cb, cb);
1546 else
1547 plug = NULL;
1548 if (plug) {
1549 bio_list_add(&plug->pending, mbio);
1550 plug->pending_cnt++;
1551 } else {
1552 spin_lock_irqsave(&conf->device_lock, flags);
1553 bio_list_add(&conf->pending_bio_list, mbio);
1554 conf->pending_count++;
1555 spin_unlock_irqrestore(&conf->device_lock, flags);
1556 md_wakeup_thread(mddev->thread);
1557 }
1558 }
1559
1560 r1_bio_write_done(r1_bio);
1561
1562 /* In case raid1d snuck in to freeze_array */
1563 wake_up(&conf->wait_barrier);
1564}
1565
1566static bool raid1_make_request(struct mddev *mddev, struct bio *bio)
1567{
1568 sector_t sectors;
1569
1570 if (unlikely(bio->bi_opf & REQ_PREFLUSH)) {
1571 md_flush_request(mddev, bio);
1572 return true;
1573 }
1574
1575 /*
1576 * There is a limit to the maximum size, but
1577 * the read/write handler might find a lower limit
1578 * due to bad blocks. To avoid multiple splits,
1579 * we pass the maximum number of sectors down
1580 * and let the lower level perform the split.
1581 */
1582 sectors = align_to_barrier_unit_end(
1583 bio->bi_iter.bi_sector, bio_sectors(bio));
1584
1585 if (bio_data_dir(bio) == READ)
1586 raid1_read_request(mddev, bio, sectors, NULL);
1587 else {
1588 if (!md_write_start(mddev,bio))
1589 return false;
1590 raid1_write_request(mddev, bio, sectors);
1591 }
1592 return true;
1593}
1594
1595static void raid1_status(struct seq_file *seq, struct mddev *mddev)
1596{
1597 struct r1conf *conf = mddev->private;
1598 int i;
1599
1600 seq_printf(seq, " [%d/%d] [", conf->raid_disks,
1601 conf->raid_disks - mddev->degraded);
1602 rcu_read_lock();
1603 for (i = 0; i < conf->raid_disks; i++) {
1604 struct md_rdev *rdev = rcu_dereference(conf->mirrors[i].rdev);
1605 seq_printf(seq, "%s",
1606 rdev && test_bit(In_sync, &rdev->flags) ? "U" : "_");
1607 }
1608 rcu_read_unlock();
1609 seq_printf(seq, "]");
1610}
1611
1612static void raid1_error(struct mddev *mddev, struct md_rdev *rdev)
1613{
1614 char b[BDEVNAME_SIZE];
1615 struct r1conf *conf = mddev->private;
1616 unsigned long flags;
1617
1618 /*
1619 * If it is not operational, then we have already marked it as dead
1620 * else if it is the last working disks with "fail_last_dev == false",
1621 * ignore the error, let the next level up know.
1622 * else mark the drive as failed
1623 */
1624 spin_lock_irqsave(&conf->device_lock, flags);
1625 if (test_bit(In_sync, &rdev->flags) && !mddev->fail_last_dev
1626 && (conf->raid_disks - mddev->degraded) == 1) {
1627 /*
1628 * Don't fail the drive, act as though we were just a
1629 * normal single drive.
1630 * However don't try a recovery from this drive as
1631 * it is very likely to fail.
1632 */
1633 conf->recovery_disabled = mddev->recovery_disabled;
1634 spin_unlock_irqrestore(&conf->device_lock, flags);
1635 return;
1636 }
1637 set_bit(Blocked, &rdev->flags);
1638 if (test_and_clear_bit(In_sync, &rdev->flags))
1639 mddev->degraded++;
1640 set_bit(Faulty, &rdev->flags);
1641 spin_unlock_irqrestore(&conf->device_lock, flags);
1642 /*
1643 * if recovery is running, make sure it aborts.
1644 */
1645 set_bit(MD_RECOVERY_INTR, &mddev->recovery);
1646 set_mask_bits(&mddev->sb_flags, 0,
1647 BIT(MD_SB_CHANGE_DEVS) | BIT(MD_SB_CHANGE_PENDING));
1648 pr_crit("md/raid1:%s: Disk failure on %s, disabling device.\n"
1649 "md/raid1:%s: Operation continuing on %d devices.\n",
1650 mdname(mddev), bdevname(rdev->bdev, b),
1651 mdname(mddev), conf->raid_disks - mddev->degraded);
1652}
1653
1654static void print_conf(struct r1conf *conf)
1655{
1656 int i;
1657
1658 pr_debug("RAID1 conf printout:\n");
1659 if (!conf) {
1660 pr_debug("(!conf)\n");
1661 return;
1662 }
1663 pr_debug(" --- wd:%d rd:%d\n", conf->raid_disks - conf->mddev->degraded,
1664 conf->raid_disks);
1665
1666 rcu_read_lock();
1667 for (i = 0; i < conf->raid_disks; i++) {
1668 char b[BDEVNAME_SIZE];
1669 struct md_rdev *rdev = rcu_dereference(conf->mirrors[i].rdev);
1670 if (rdev)
1671 pr_debug(" disk %d, wo:%d, o:%d, dev:%s\n",
1672 i, !test_bit(In_sync, &rdev->flags),
1673 !test_bit(Faulty, &rdev->flags),
1674 bdevname(rdev->bdev,b));
1675 }
1676 rcu_read_unlock();
1677}
1678
1679static void close_sync(struct r1conf *conf)
1680{
1681 int idx;
1682
1683 for (idx = 0; idx < BARRIER_BUCKETS_NR; idx++) {
1684 _wait_barrier(conf, idx);
1685 _allow_barrier(conf, idx);
1686 }
1687
1688 mempool_exit(&conf->r1buf_pool);
1689}
1690
1691static int raid1_spare_active(struct mddev *mddev)
1692{
1693 int i;
1694 struct r1conf *conf = mddev->private;
1695 int count = 0;
1696 unsigned long flags;
1697
1698 /*
1699 * Find all failed disks within the RAID1 configuration
1700 * and mark them readable.
1701 * Called under mddev lock, so rcu protection not needed.
1702 * device_lock used to avoid races with raid1_end_read_request
1703 * which expects 'In_sync' flags and ->degraded to be consistent.
1704 */
1705 spin_lock_irqsave(&conf->device_lock, flags);
1706 for (i = 0; i < conf->raid_disks; i++) {
1707 struct md_rdev *rdev = conf->mirrors[i].rdev;
1708 struct md_rdev *repl = conf->mirrors[conf->raid_disks + i].rdev;
1709 if (repl
1710 && !test_bit(Candidate, &repl->flags)
1711 && repl->recovery_offset == MaxSector
1712 && !test_bit(Faulty, &repl->flags)
1713 && !test_and_set_bit(In_sync, &repl->flags)) {
1714 /* replacement has just become active */
1715 if (!rdev ||
1716 !test_and_clear_bit(In_sync, &rdev->flags))
1717 count++;
1718 if (rdev) {
1719 /* Replaced device not technically
1720 * faulty, but we need to be sure
1721 * it gets removed and never re-added
1722 */
1723 set_bit(Faulty, &rdev->flags);
1724 sysfs_notify_dirent_safe(
1725 rdev->sysfs_state);
1726 }
1727 }
1728 if (rdev
1729 && rdev->recovery_offset == MaxSector
1730 && !test_bit(Faulty, &rdev->flags)
1731 && !test_and_set_bit(In_sync, &rdev->flags)) {
1732 count++;
1733 sysfs_notify_dirent_safe(rdev->sysfs_state);
1734 }
1735 }
1736 mddev->degraded -= count;
1737 spin_unlock_irqrestore(&conf->device_lock, flags);
1738
1739 print_conf(conf);
1740 return count;
1741}
1742
1743static int raid1_add_disk(struct mddev *mddev, struct md_rdev *rdev)
1744{
1745 struct r1conf *conf = mddev->private;
1746 int err = -EEXIST;
1747 int mirror = 0;
1748 struct raid1_info *p;
1749 int first = 0;
1750 int last = conf->raid_disks - 1;
1751
1752 if (mddev->recovery_disabled == conf->recovery_disabled)
1753 return -EBUSY;
1754
1755 if (md_integrity_add_rdev(rdev, mddev))
1756 return -ENXIO;
1757
1758 if (rdev->raid_disk >= 0)
1759 first = last = rdev->raid_disk;
1760
1761 /*
1762 * find the disk ... but prefer rdev->saved_raid_disk
1763 * if possible.
1764 */
1765 if (rdev->saved_raid_disk >= 0 &&
1766 rdev->saved_raid_disk >= first &&
1767 rdev->saved_raid_disk < conf->raid_disks &&
1768 conf->mirrors[rdev->saved_raid_disk].rdev == NULL)
1769 first = last = rdev->saved_raid_disk;
1770
1771 for (mirror = first; mirror <= last; mirror++) {
1772 p = conf->mirrors + mirror;
1773 if (!p->rdev) {
1774 if (mddev->gendisk)
1775 disk_stack_limits(mddev->gendisk, rdev->bdev,
1776 rdev->data_offset << 9);
1777
1778 p->head_position = 0;
1779 rdev->raid_disk = mirror;
1780 err = 0;
1781 /* As all devices are equivalent, we don't need a full recovery
1782 * if this was recently any drive of the array
1783 */
1784 if (rdev->saved_raid_disk < 0)
1785 conf->fullsync = 1;
1786 rcu_assign_pointer(p->rdev, rdev);
1787 break;
1788 }
1789 if (test_bit(WantReplacement, &p->rdev->flags) &&
1790 p[conf->raid_disks].rdev == NULL) {
1791 /* Add this device as a replacement */
1792 clear_bit(In_sync, &rdev->flags);
1793 set_bit(Replacement, &rdev->flags);
1794 rdev->raid_disk = mirror;
1795 err = 0;
1796 conf->fullsync = 1;
1797 rcu_assign_pointer(p[conf->raid_disks].rdev, rdev);
1798 break;
1799 }
1800 }
1801 if (mddev->queue && blk_queue_discard(bdev_get_queue(rdev->bdev)))
1802 blk_queue_flag_set(QUEUE_FLAG_DISCARD, mddev->queue);
1803 print_conf(conf);
1804 return err;
1805}
1806
1807static int raid1_remove_disk(struct mddev *mddev, struct md_rdev *rdev)
1808{
1809 struct r1conf *conf = mddev->private;
1810 int err = 0;
1811 int number = rdev->raid_disk;
1812 struct raid1_info *p = conf->mirrors + number;
1813
1814 if (rdev != p->rdev)
1815 p = conf->mirrors + conf->raid_disks + number;
1816
1817 print_conf(conf);
1818 if (rdev == p->rdev) {
1819 if (test_bit(In_sync, &rdev->flags) ||
1820 atomic_read(&rdev->nr_pending)) {
1821 err = -EBUSY;
1822 goto abort;
1823 }
1824 /* Only remove non-faulty devices if recovery
1825 * is not possible.
1826 */
1827 if (!test_bit(Faulty, &rdev->flags) &&
1828 mddev->recovery_disabled != conf->recovery_disabled &&
1829 mddev->degraded < conf->raid_disks) {
1830 err = -EBUSY;
1831 goto abort;
1832 }
1833 p->rdev = NULL;
1834 if (!test_bit(RemoveSynchronized, &rdev->flags)) {
1835 synchronize_rcu();
1836 if (atomic_read(&rdev->nr_pending)) {
1837 /* lost the race, try later */
1838 err = -EBUSY;
1839 p->rdev = rdev;
1840 goto abort;
1841 }
1842 }
1843 if (conf->mirrors[conf->raid_disks + number].rdev) {
1844 /* We just removed a device that is being replaced.
1845 * Move down the replacement. We drain all IO before
1846 * doing this to avoid confusion.
1847 */
1848 struct md_rdev *repl =
1849 conf->mirrors[conf->raid_disks + number].rdev;
1850 freeze_array(conf, 0);
1851 if (atomic_read(&repl->nr_pending)) {
1852 /* It means that some queued IO of retry_list
1853 * hold repl. Thus, we cannot set replacement
1854 * as NULL, avoiding rdev NULL pointer
1855 * dereference in sync_request_write and
1856 * handle_write_finished.
1857 */
1858 err = -EBUSY;
1859 unfreeze_array(conf);
1860 goto abort;
1861 }
1862 clear_bit(Replacement, &repl->flags);
1863 p->rdev = repl;
1864 conf->mirrors[conf->raid_disks + number].rdev = NULL;
1865 unfreeze_array(conf);
1866 }
1867
1868 clear_bit(WantReplacement, &rdev->flags);
1869 err = md_integrity_register(mddev);
1870 }
1871abort:
1872
1873 print_conf(conf);
1874 return err;
1875}
1876
1877static void end_sync_read(struct bio *bio)
1878{
1879 struct r1bio *r1_bio = get_resync_r1bio(bio);
1880
1881 update_head_pos(r1_bio->read_disk, r1_bio);
1882
1883 /*
1884 * we have read a block, now it needs to be re-written,
1885 * or re-read if the read failed.
1886 * We don't do much here, just schedule handling by raid1d
1887 */
1888 if (!bio->bi_status)
1889 set_bit(R1BIO_Uptodate, &r1_bio->state);
1890
1891 if (atomic_dec_and_test(&r1_bio->remaining))
1892 reschedule_retry(r1_bio);
1893}
1894
1895static void abort_sync_write(struct mddev *mddev, struct r1bio *r1_bio)
1896{
1897 sector_t sync_blocks = 0;
1898 sector_t s = r1_bio->sector;
1899 long sectors_to_go = r1_bio->sectors;
1900
1901 /* make sure these bits don't get cleared. */
1902 do {
1903 md_bitmap_end_sync(mddev->bitmap, s, &sync_blocks, 1);
1904 s += sync_blocks;
1905 sectors_to_go -= sync_blocks;
1906 } while (sectors_to_go > 0);
1907}
1908
1909static void put_sync_write_buf(struct r1bio *r1_bio, int uptodate)
1910{
1911 if (atomic_dec_and_test(&r1_bio->remaining)) {
1912 struct mddev *mddev = r1_bio->mddev;
1913 int s = r1_bio->sectors;
1914
1915 if (test_bit(R1BIO_MadeGood, &r1_bio->state) ||
1916 test_bit(R1BIO_WriteError, &r1_bio->state))
1917 reschedule_retry(r1_bio);
1918 else {
1919 put_buf(r1_bio);
1920 md_done_sync(mddev, s, uptodate);
1921 }
1922 }
1923}
1924
1925static void end_sync_write(struct bio *bio)
1926{
1927 int uptodate = !bio->bi_status;
1928 struct r1bio *r1_bio = get_resync_r1bio(bio);
1929 struct mddev *mddev = r1_bio->mddev;
1930 struct r1conf *conf = mddev->private;
1931 sector_t first_bad;
1932 int bad_sectors;
1933 struct md_rdev *rdev = conf->mirrors[find_bio_disk(r1_bio, bio)].rdev;
1934
1935 if (!uptodate) {
1936 abort_sync_write(mddev, r1_bio);
1937 set_bit(WriteErrorSeen, &rdev->flags);
1938 if (!test_and_set_bit(WantReplacement, &rdev->flags))
1939 set_bit(MD_RECOVERY_NEEDED, &
1940 mddev->recovery);
1941 set_bit(R1BIO_WriteError, &r1_bio->state);
1942 } else if (is_badblock(rdev, r1_bio->sector, r1_bio->sectors,
1943 &first_bad, &bad_sectors) &&
1944 !is_badblock(conf->mirrors[r1_bio->read_disk].rdev,
1945 r1_bio->sector,
1946 r1_bio->sectors,
1947 &first_bad, &bad_sectors)
1948 )
1949 set_bit(R1BIO_MadeGood, &r1_bio->state);
1950
1951 put_sync_write_buf(r1_bio, uptodate);
1952}
1953
1954static int r1_sync_page_io(struct md_rdev *rdev, sector_t sector,
1955 int sectors, struct page *page, int rw)
1956{
1957 if (sync_page_io(rdev, sector, sectors << 9, page, rw, 0, false))
1958 /* success */
1959 return 1;
1960 if (rw == WRITE) {
1961 set_bit(WriteErrorSeen, &rdev->flags);
1962 if (!test_and_set_bit(WantReplacement,
1963 &rdev->flags))
1964 set_bit(MD_RECOVERY_NEEDED, &
1965 rdev->mddev->recovery);
1966 }
1967 /* need to record an error - either for the block or the device */
1968 if (!rdev_set_badblocks(rdev, sector, sectors, 0))
1969 md_error(rdev->mddev, rdev);
1970 return 0;
1971}
1972
1973static int fix_sync_read_error(struct r1bio *r1_bio)
1974{
1975 /* Try some synchronous reads of other devices to get
1976 * good data, much like with normal read errors. Only
1977 * read into the pages we already have so we don't
1978 * need to re-issue the read request.
1979 * We don't need to freeze the array, because being in an
1980 * active sync request, there is no normal IO, and
1981 * no overlapping syncs.
1982 * We don't need to check is_badblock() again as we
1983 * made sure that anything with a bad block in range
1984 * will have bi_end_io clear.
1985 */
1986 struct mddev *mddev = r1_bio->mddev;
1987 struct r1conf *conf = mddev->private;
1988 struct bio *bio = r1_bio->bios[r1_bio->read_disk];
1989 struct page **pages = get_resync_pages(bio)->pages;
1990 sector_t sect = r1_bio->sector;
1991 int sectors = r1_bio->sectors;
1992 int idx = 0;
1993 struct md_rdev *rdev;
1994
1995 rdev = conf->mirrors[r1_bio->read_disk].rdev;
1996 if (test_bit(FailFast, &rdev->flags)) {
1997 /* Don't try recovering from here - just fail it
1998 * ... unless it is the last working device of course */
1999 md_error(mddev, rdev);
2000 if (test_bit(Faulty, &rdev->flags))
2001 /* Don't try to read from here, but make sure
2002 * put_buf does it's thing
2003 */
2004 bio->bi_end_io = end_sync_write;
2005 }
2006
2007 while(sectors) {
2008 int s = sectors;
2009 int d = r1_bio->read_disk;
2010 int success = 0;
2011 int start;
2012
2013 if (s > (PAGE_SIZE>>9))
2014 s = PAGE_SIZE >> 9;
2015 do {
2016 if (r1_bio->bios[d]->bi_end_io == end_sync_read) {
2017 /* No rcu protection needed here devices
2018 * can only be removed when no resync is
2019 * active, and resync is currently active
2020 */
2021 rdev = conf->mirrors[d].rdev;
2022 if (sync_page_io(rdev, sect, s<<9,
2023 pages[idx],
2024 REQ_OP_READ, 0, false)) {
2025 success = 1;
2026 break;
2027 }
2028 }
2029 d++;
2030 if (d == conf->raid_disks * 2)
2031 d = 0;
2032 } while (!success && d != r1_bio->read_disk);
2033
2034 if (!success) {
2035 char b[BDEVNAME_SIZE];
2036 int abort = 0;
2037 /* Cannot read from anywhere, this block is lost.
2038 * Record a bad block on each device. If that doesn't
2039 * work just disable and interrupt the recovery.
2040 * Don't fail devices as that won't really help.
2041 */
2042 pr_crit_ratelimited("md/raid1:%s: %s: unrecoverable I/O read error for block %llu\n",
2043 mdname(mddev), bio_devname(bio, b),
2044 (unsigned long long)r1_bio->sector);
2045 for (d = 0; d < conf->raid_disks * 2; d++) {
2046 rdev = conf->mirrors[d].rdev;
2047 if (!rdev || test_bit(Faulty, &rdev->flags))
2048 continue;
2049 if (!rdev_set_badblocks(rdev, sect, s, 0))
2050 abort = 1;
2051 }
2052 if (abort) {
2053 conf->recovery_disabled =
2054 mddev->recovery_disabled;
2055 set_bit(MD_RECOVERY_INTR, &mddev->recovery);
2056 md_done_sync(mddev, r1_bio->sectors, 0);
2057 put_buf(r1_bio);
2058 return 0;
2059 }
2060 /* Try next page */
2061 sectors -= s;
2062 sect += s;
2063 idx++;
2064 continue;
2065 }
2066
2067 start = d;
2068 /* write it back and re-read */
2069 while (d != r1_bio->read_disk) {
2070 if (d == 0)
2071 d = conf->raid_disks * 2;
2072 d--;
2073 if (r1_bio->bios[d]->bi_end_io != end_sync_read)
2074 continue;
2075 rdev = conf->mirrors[d].rdev;
2076 if (r1_sync_page_io(rdev, sect, s,
2077 pages[idx],
2078 WRITE) == 0) {
2079 r1_bio->bios[d]->bi_end_io = NULL;
2080 rdev_dec_pending(rdev, mddev);
2081 }
2082 }
2083 d = start;
2084 while (d != r1_bio->read_disk) {
2085 if (d == 0)
2086 d = conf->raid_disks * 2;
2087 d--;
2088 if (r1_bio->bios[d]->bi_end_io != end_sync_read)
2089 continue;
2090 rdev = conf->mirrors[d].rdev;
2091 if (r1_sync_page_io(rdev, sect, s,
2092 pages[idx],
2093 READ) != 0)
2094 atomic_add(s, &rdev->corrected_errors);
2095 }
2096 sectors -= s;
2097 sect += s;
2098 idx ++;
2099 }
2100 set_bit(R1BIO_Uptodate, &r1_bio->state);
2101 bio->bi_status = 0;
2102 return 1;
2103}
2104
2105static void process_checks(struct r1bio *r1_bio)
2106{
2107 /* We have read all readable devices. If we haven't
2108 * got the block, then there is no hope left.
2109 * If we have, then we want to do a comparison
2110 * and skip the write if everything is the same.
2111 * If any blocks failed to read, then we need to
2112 * attempt an over-write
2113 */
2114 struct mddev *mddev = r1_bio->mddev;
2115 struct r1conf *conf = mddev->private;
2116 int primary;
2117 int i;
2118 int vcnt;
2119
2120 /* Fix variable parts of all bios */
2121 vcnt = (r1_bio->sectors + PAGE_SIZE / 512 - 1) >> (PAGE_SHIFT - 9);
2122 for (i = 0; i < conf->raid_disks * 2; i++) {
2123 blk_status_t status;
2124 struct bio *b = r1_bio->bios[i];
2125 struct resync_pages *rp = get_resync_pages(b);
2126 if (b->bi_end_io != end_sync_read)
2127 continue;
2128 /* fixup the bio for reuse, but preserve errno */
2129 status = b->bi_status;
2130 bio_reset(b);
2131 b->bi_status = status;
2132 b->bi_iter.bi_sector = r1_bio->sector +
2133 conf->mirrors[i].rdev->data_offset;
2134 bio_set_dev(b, conf->mirrors[i].rdev->bdev);
2135 b->bi_end_io = end_sync_read;
2136 rp->raid_bio = r1_bio;
2137 b->bi_private = rp;
2138
2139 /* initialize bvec table again */
2140 md_bio_reset_resync_pages(b, rp, r1_bio->sectors << 9);
2141 }
2142 for (primary = 0; primary < conf->raid_disks * 2; primary++)
2143 if (r1_bio->bios[primary]->bi_end_io == end_sync_read &&
2144 !r1_bio->bios[primary]->bi_status) {
2145 r1_bio->bios[primary]->bi_end_io = NULL;
2146 rdev_dec_pending(conf->mirrors[primary].rdev, mddev);
2147 break;
2148 }
2149 r1_bio->read_disk = primary;
2150 for (i = 0; i < conf->raid_disks * 2; i++) {
2151 int j = 0;
2152 struct bio *pbio = r1_bio->bios[primary];
2153 struct bio *sbio = r1_bio->bios[i];
2154 blk_status_t status = sbio->bi_status;
2155 struct page **ppages = get_resync_pages(pbio)->pages;
2156 struct page **spages = get_resync_pages(sbio)->pages;
2157 struct bio_vec *bi;
2158 int page_len[RESYNC_PAGES] = { 0 };
2159 struct bvec_iter_all iter_all;
2160
2161 if (sbio->bi_end_io != end_sync_read)
2162 continue;
2163 /* Now we can 'fixup' the error value */
2164 sbio->bi_status = 0;
2165
2166 bio_for_each_segment_all(bi, sbio, iter_all)
2167 page_len[j++] = bi->bv_len;
2168
2169 if (!status) {
2170 for (j = vcnt; j-- ; ) {
2171 if (memcmp(page_address(ppages[j]),
2172 page_address(spages[j]),
2173 page_len[j]))
2174 break;
2175 }
2176 } else
2177 j = 0;
2178 if (j >= 0)
2179 atomic64_add(r1_bio->sectors, &mddev->resync_mismatches);
2180 if (j < 0 || (test_bit(MD_RECOVERY_CHECK, &mddev->recovery)
2181 && !status)) {
2182 /* No need to write to this device. */
2183 sbio->bi_end_io = NULL;
2184 rdev_dec_pending(conf->mirrors[i].rdev, mddev);
2185 continue;
2186 }
2187
2188 bio_copy_data(sbio, pbio);
2189 }
2190}
2191
2192static void sync_request_write(struct mddev *mddev, struct r1bio *r1_bio)
2193{
2194 struct r1conf *conf = mddev->private;
2195 int i;
2196 int disks = conf->raid_disks * 2;
2197 struct bio *wbio;
2198
2199 if (!test_bit(R1BIO_Uptodate, &r1_bio->state))
2200 /* ouch - failed to read all of that. */
2201 if (!fix_sync_read_error(r1_bio))
2202 return;
2203
2204 if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
2205 process_checks(r1_bio);
2206
2207 /*
2208 * schedule writes
2209 */
2210 atomic_set(&r1_bio->remaining, 1);
2211 for (i = 0; i < disks ; i++) {
2212 wbio = r1_bio->bios[i];
2213 if (wbio->bi_end_io == NULL ||
2214 (wbio->bi_end_io == end_sync_read &&
2215 (i == r1_bio->read_disk ||
2216 !test_bit(MD_RECOVERY_SYNC, &mddev->recovery))))
2217 continue;
2218 if (test_bit(Faulty, &conf->mirrors[i].rdev->flags)) {
2219 abort_sync_write(mddev, r1_bio);
2220 continue;
2221 }
2222
2223 bio_set_op_attrs(wbio, REQ_OP_WRITE, 0);
2224 if (test_bit(FailFast, &conf->mirrors[i].rdev->flags))
2225 wbio->bi_opf |= MD_FAILFAST;
2226
2227 wbio->bi_end_io = end_sync_write;
2228 atomic_inc(&r1_bio->remaining);
2229 md_sync_acct(conf->mirrors[i].rdev->bdev, bio_sectors(wbio));
2230
2231 generic_make_request(wbio);
2232 }
2233
2234 put_sync_write_buf(r1_bio, 1);
2235}
2236
2237/*
2238 * This is a kernel thread which:
2239 *
2240 * 1. Retries failed read operations on working mirrors.
2241 * 2. Updates the raid superblock when problems encounter.
2242 * 3. Performs writes following reads for array synchronising.
2243 */
2244
2245static void fix_read_error(struct r1conf *conf, int read_disk,
2246 sector_t sect, int sectors)
2247{
2248 struct mddev *mddev = conf->mddev;
2249 while(sectors) {
2250 int s = sectors;
2251 int d = read_disk;
2252 int success = 0;
2253 int start;
2254 struct md_rdev *rdev;
2255
2256 if (s > (PAGE_SIZE>>9))
2257 s = PAGE_SIZE >> 9;
2258
2259 do {
2260 sector_t first_bad;
2261 int bad_sectors;
2262
2263 rcu_read_lock();
2264 rdev = rcu_dereference(conf->mirrors[d].rdev);
2265 if (rdev &&
2266 (test_bit(In_sync, &rdev->flags) ||
2267 (!test_bit(Faulty, &rdev->flags) &&
2268 rdev->recovery_offset >= sect + s)) &&
2269 is_badblock(rdev, sect, s,
2270 &first_bad, &bad_sectors) == 0) {
2271 atomic_inc(&rdev->nr_pending);
2272 rcu_read_unlock();
2273 if (sync_page_io(rdev, sect, s<<9,
2274 conf->tmppage, REQ_OP_READ, 0, false))
2275 success = 1;
2276 rdev_dec_pending(rdev, mddev);
2277 if (success)
2278 break;
2279 } else
2280 rcu_read_unlock();
2281 d++;
2282 if (d == conf->raid_disks * 2)
2283 d = 0;
2284 } while (!success && d != read_disk);
2285
2286 if (!success) {
2287 /* Cannot read from anywhere - mark it bad */
2288 struct md_rdev *rdev = conf->mirrors[read_disk].rdev;
2289 if (!rdev_set_badblocks(rdev, sect, s, 0))
2290 md_error(mddev, rdev);
2291 break;
2292 }
2293 /* write it back and re-read */
2294 start = d;
2295 while (d != read_disk) {
2296 if (d==0)
2297 d = conf->raid_disks * 2;
2298 d--;
2299 rcu_read_lock();
2300 rdev = rcu_dereference(conf->mirrors[d].rdev);
2301 if (rdev &&
2302 !test_bit(Faulty, &rdev->flags)) {
2303 atomic_inc(&rdev->nr_pending);
2304 rcu_read_unlock();
2305 r1_sync_page_io(rdev, sect, s,
2306 conf->tmppage, WRITE);
2307 rdev_dec_pending(rdev, mddev);
2308 } else
2309 rcu_read_unlock();
2310 }
2311 d = start;
2312 while (d != read_disk) {
2313 char b[BDEVNAME_SIZE];
2314 if (d==0)
2315 d = conf->raid_disks * 2;
2316 d--;
2317 rcu_read_lock();
2318 rdev = rcu_dereference(conf->mirrors[d].rdev);
2319 if (rdev &&
2320 !test_bit(Faulty, &rdev->flags)) {
2321 atomic_inc(&rdev->nr_pending);
2322 rcu_read_unlock();
2323 if (r1_sync_page_io(rdev, sect, s,
2324 conf->tmppage, READ)) {
2325 atomic_add(s, &rdev->corrected_errors);
2326 pr_info("md/raid1:%s: read error corrected (%d sectors at %llu on %s)\n",
2327 mdname(mddev), s,
2328 (unsigned long long)(sect +
2329 rdev->data_offset),
2330 bdevname(rdev->bdev, b));
2331 }
2332 rdev_dec_pending(rdev, mddev);
2333 } else
2334 rcu_read_unlock();
2335 }
2336 sectors -= s;
2337 sect += s;
2338 }
2339}
2340
2341static int narrow_write_error(struct r1bio *r1_bio, int i)
2342{
2343 struct mddev *mddev = r1_bio->mddev;
2344 struct r1conf *conf = mddev->private;
2345 struct md_rdev *rdev = conf->mirrors[i].rdev;
2346
2347 /* bio has the data to be written to device 'i' where
2348 * we just recently had a write error.
2349 * We repeatedly clone the bio and trim down to one block,
2350 * then try the write. Where the write fails we record
2351 * a bad block.
2352 * It is conceivable that the bio doesn't exactly align with
2353 * blocks. We must handle this somehow.
2354 *
2355 * We currently own a reference on the rdev.
2356 */
2357
2358 int block_sectors;
2359 sector_t sector;
2360 int sectors;
2361 int sect_to_write = r1_bio->sectors;
2362 int ok = 1;
2363
2364 if (rdev->badblocks.shift < 0)
2365 return 0;
2366
2367 block_sectors = roundup(1 << rdev->badblocks.shift,
2368 bdev_logical_block_size(rdev->bdev) >> 9);
2369 sector = r1_bio->sector;
2370 sectors = ((sector + block_sectors)
2371 & ~(sector_t)(block_sectors - 1))
2372 - sector;
2373
2374 while (sect_to_write) {
2375 struct bio *wbio;
2376 if (sectors > sect_to_write)
2377 sectors = sect_to_write;
2378 /* Write at 'sector' for 'sectors'*/
2379
2380 if (test_bit(R1BIO_BehindIO, &r1_bio->state)) {
2381 wbio = bio_clone_fast(r1_bio->behind_master_bio,
2382 GFP_NOIO,
2383 &mddev->bio_set);
2384 } else {
2385 wbio = bio_clone_fast(r1_bio->master_bio, GFP_NOIO,
2386 &mddev->bio_set);
2387 }
2388
2389 bio_set_op_attrs(wbio, REQ_OP_WRITE, 0);
2390 wbio->bi_iter.bi_sector = r1_bio->sector;
2391 wbio->bi_iter.bi_size = r1_bio->sectors << 9;
2392
2393 bio_trim(wbio, sector - r1_bio->sector, sectors);
2394 wbio->bi_iter.bi_sector += rdev->data_offset;
2395 bio_set_dev(wbio, rdev->bdev);
2396
2397 if (submit_bio_wait(wbio) < 0)
2398 /* failure! */
2399 ok = rdev_set_badblocks(rdev, sector,
2400 sectors, 0)
2401 && ok;
2402
2403 bio_put(wbio);
2404 sect_to_write -= sectors;
2405 sector += sectors;
2406 sectors = block_sectors;
2407 }
2408 return ok;
2409}
2410
2411static void handle_sync_write_finished(struct r1conf *conf, struct r1bio *r1_bio)
2412{
2413 int m;
2414 int s = r1_bio->sectors;
2415 for (m = 0; m < conf->raid_disks * 2 ; m++) {
2416 struct md_rdev *rdev = conf->mirrors[m].rdev;
2417 struct bio *bio = r1_bio->bios[m];
2418 if (bio->bi_end_io == NULL)
2419 continue;
2420 if (!bio->bi_status &&
2421 test_bit(R1BIO_MadeGood, &r1_bio->state)) {
2422 rdev_clear_badblocks(rdev, r1_bio->sector, s, 0);
2423 }
2424 if (bio->bi_status &&
2425 test_bit(R1BIO_WriteError, &r1_bio->state)) {
2426 if (!rdev_set_badblocks(rdev, r1_bio->sector, s, 0))
2427 md_error(conf->mddev, rdev);
2428 }
2429 }
2430 put_buf(r1_bio);
2431 md_done_sync(conf->mddev, s, 1);
2432}
2433
2434static void handle_write_finished(struct r1conf *conf, struct r1bio *r1_bio)
2435{
2436 int m, idx;
2437 bool fail = false;
2438
2439 for (m = 0; m < conf->raid_disks * 2 ; m++)
2440 if (r1_bio->bios[m] == IO_MADE_GOOD) {
2441 struct md_rdev *rdev = conf->mirrors[m].rdev;
2442 rdev_clear_badblocks(rdev,
2443 r1_bio->sector,
2444 r1_bio->sectors, 0);
2445 rdev_dec_pending(rdev, conf->mddev);
2446 } else if (r1_bio->bios[m] != NULL) {
2447 /* This drive got a write error. We need to
2448 * narrow down and record precise write
2449 * errors.
2450 */
2451 fail = true;
2452 if (!narrow_write_error(r1_bio, m)) {
2453 md_error(conf->mddev,
2454 conf->mirrors[m].rdev);
2455 /* an I/O failed, we can't clear the bitmap */
2456 set_bit(R1BIO_Degraded, &r1_bio->state);
2457 }
2458 rdev_dec_pending(conf->mirrors[m].rdev,
2459 conf->mddev);
2460 }
2461 if (fail) {
2462 spin_lock_irq(&conf->device_lock);
2463 list_add(&r1_bio->retry_list, &conf->bio_end_io_list);
2464 idx = sector_to_idx(r1_bio->sector);
2465 atomic_inc(&conf->nr_queued[idx]);
2466 spin_unlock_irq(&conf->device_lock);
2467 /*
2468 * In case freeze_array() is waiting for condition
2469 * get_unqueued_pending() == extra to be true.
2470 */
2471 wake_up(&conf->wait_barrier);
2472 md_wakeup_thread(conf->mddev->thread);
2473 } else {
2474 if (test_bit(R1BIO_WriteError, &r1_bio->state))
2475 close_write(r1_bio);
2476 raid_end_bio_io(r1_bio);
2477 }
2478}
2479
2480static void handle_read_error(struct r1conf *conf, struct r1bio *r1_bio)
2481{
2482 struct mddev *mddev = conf->mddev;
2483 struct bio *bio;
2484 struct md_rdev *rdev;
2485
2486 clear_bit(R1BIO_ReadError, &r1_bio->state);
2487 /* we got a read error. Maybe the drive is bad. Maybe just
2488 * the block and we can fix it.
2489 * We freeze all other IO, and try reading the block from
2490 * other devices. When we find one, we re-write
2491 * and check it that fixes the read error.
2492 * This is all done synchronously while the array is
2493 * frozen
2494 */
2495
2496 bio = r1_bio->bios[r1_bio->read_disk];
2497 bio_put(bio);
2498 r1_bio->bios[r1_bio->read_disk] = NULL;
2499
2500 rdev = conf->mirrors[r1_bio->read_disk].rdev;
2501 if (mddev->ro == 0
2502 && !test_bit(FailFast, &rdev->flags)) {
2503 freeze_array(conf, 1);
2504 fix_read_error(conf, r1_bio->read_disk,
2505 r1_bio->sector, r1_bio->sectors);
2506 unfreeze_array(conf);
2507 } else if (mddev->ro == 0 && test_bit(FailFast, &rdev->flags)) {
2508 md_error(mddev, rdev);
2509 } else {
2510 r1_bio->bios[r1_bio->read_disk] = IO_BLOCKED;
2511 }
2512
2513 rdev_dec_pending(rdev, conf->mddev);
2514 allow_barrier(conf, r1_bio->sector);
2515 bio = r1_bio->master_bio;
2516
2517 /* Reuse the old r1_bio so that the IO_BLOCKED settings are preserved */
2518 r1_bio->state = 0;
2519 raid1_read_request(mddev, bio, r1_bio->sectors, r1_bio);
2520}
2521
2522static void raid1d(struct md_thread *thread)
2523{
2524 struct mddev *mddev = thread->mddev;
2525 struct r1bio *r1_bio;
2526 unsigned long flags;
2527 struct r1conf *conf = mddev->private;
2528 struct list_head *head = &conf->retry_list;
2529 struct blk_plug plug;
2530 int idx;
2531
2532 md_check_recovery(mddev);
2533
2534 if (!list_empty_careful(&conf->bio_end_io_list) &&
2535 !test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags)) {
2536 LIST_HEAD(tmp);
2537 spin_lock_irqsave(&conf->device_lock, flags);
2538 if (!test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags))
2539 list_splice_init(&conf->bio_end_io_list, &tmp);
2540 spin_unlock_irqrestore(&conf->device_lock, flags);
2541 while (!list_empty(&tmp)) {
2542 r1_bio = list_first_entry(&tmp, struct r1bio,
2543 retry_list);
2544 list_del(&r1_bio->retry_list);
2545 idx = sector_to_idx(r1_bio->sector);
2546 atomic_dec(&conf->nr_queued[idx]);
2547 if (mddev->degraded)
2548 set_bit(R1BIO_Degraded, &r1_bio->state);
2549 if (test_bit(R1BIO_WriteError, &r1_bio->state))
2550 close_write(r1_bio);
2551 raid_end_bio_io(r1_bio);
2552 }
2553 }
2554
2555 blk_start_plug(&plug);
2556 for (;;) {
2557
2558 flush_pending_writes(conf);
2559
2560 spin_lock_irqsave(&conf->device_lock, flags);
2561 if (list_empty(head)) {
2562 spin_unlock_irqrestore(&conf->device_lock, flags);
2563 break;
2564 }
2565 r1_bio = list_entry(head->prev, struct r1bio, retry_list);
2566 list_del(head->prev);
2567 idx = sector_to_idx(r1_bio->sector);
2568 atomic_dec(&conf->nr_queued[idx]);
2569 spin_unlock_irqrestore(&conf->device_lock, flags);
2570
2571 mddev = r1_bio->mddev;
2572 conf = mddev->private;
2573 if (test_bit(R1BIO_IsSync, &r1_bio->state)) {
2574 if (test_bit(R1BIO_MadeGood, &r1_bio->state) ||
2575 test_bit(R1BIO_WriteError, &r1_bio->state))
2576 handle_sync_write_finished(conf, r1_bio);
2577 else
2578 sync_request_write(mddev, r1_bio);
2579 } else if (test_bit(R1BIO_MadeGood, &r1_bio->state) ||
2580 test_bit(R1BIO_WriteError, &r1_bio->state))
2581 handle_write_finished(conf, r1_bio);
2582 else if (test_bit(R1BIO_ReadError, &r1_bio->state))
2583 handle_read_error(conf, r1_bio);
2584 else
2585 WARN_ON_ONCE(1);
2586
2587 cond_resched();
2588 if (mddev->sb_flags & ~(1<<MD_SB_CHANGE_PENDING))
2589 md_check_recovery(mddev);
2590 }
2591 blk_finish_plug(&plug);
2592}
2593
2594static int init_resync(struct r1conf *conf)
2595{
2596 int buffs;
2597
2598 buffs = RESYNC_WINDOW / RESYNC_BLOCK_SIZE;
2599 BUG_ON(mempool_initialized(&conf->r1buf_pool));
2600
2601 return mempool_init(&conf->r1buf_pool, buffs, r1buf_pool_alloc,
2602 r1buf_pool_free, conf->poolinfo);
2603}
2604
2605static struct r1bio *raid1_alloc_init_r1buf(struct r1conf *conf)
2606{
2607 struct r1bio *r1bio = mempool_alloc(&conf->r1buf_pool, GFP_NOIO);
2608 struct resync_pages *rps;
2609 struct bio *bio;
2610 int i;
2611
2612 for (i = conf->poolinfo->raid_disks; i--; ) {
2613 bio = r1bio->bios[i];
2614 rps = bio->bi_private;
2615 bio_reset(bio);
2616 bio->bi_private = rps;
2617 }
2618 r1bio->master_bio = NULL;
2619 return r1bio;
2620}
2621
2622/*
2623 * perform a "sync" on one "block"
2624 *
2625 * We need to make sure that no normal I/O request - particularly write
2626 * requests - conflict with active sync requests.
2627 *
2628 * This is achieved by tracking pending requests and a 'barrier' concept
2629 * that can be installed to exclude normal IO requests.
2630 */
2631
2632static sector_t raid1_sync_request(struct mddev *mddev, sector_t sector_nr,
2633 int *skipped)
2634{
2635 struct r1conf *conf = mddev->private;
2636 struct r1bio *r1_bio;
2637 struct bio *bio;
2638 sector_t max_sector, nr_sectors;
2639 int disk = -1;
2640 int i;
2641 int wonly = -1;
2642 int write_targets = 0, read_targets = 0;
2643 sector_t sync_blocks;
2644 int still_degraded = 0;
2645 int good_sectors = RESYNC_SECTORS;
2646 int min_bad = 0; /* number of sectors that are bad in all devices */
2647 int idx = sector_to_idx(sector_nr);
2648 int page_idx = 0;
2649
2650 if (!mempool_initialized(&conf->r1buf_pool))
2651 if (init_resync(conf))
2652 return 0;
2653
2654 max_sector = mddev->dev_sectors;
2655 if (sector_nr >= max_sector) {
2656 /* If we aborted, we need to abort the
2657 * sync on the 'current' bitmap chunk (there will
2658 * only be one in raid1 resync.
2659 * We can find the current addess in mddev->curr_resync
2660 */
2661 if (mddev->curr_resync < max_sector) /* aborted */
2662 md_bitmap_end_sync(mddev->bitmap, mddev->curr_resync,
2663 &sync_blocks, 1);
2664 else /* completed sync */
2665 conf->fullsync = 0;
2666
2667 md_bitmap_close_sync(mddev->bitmap);
2668 close_sync(conf);
2669
2670 if (mddev_is_clustered(mddev)) {
2671 conf->cluster_sync_low = 0;
2672 conf->cluster_sync_high = 0;
2673 }
2674 return 0;
2675 }
2676
2677 if (mddev->bitmap == NULL &&
2678 mddev->recovery_cp == MaxSector &&
2679 !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery) &&
2680 conf->fullsync == 0) {
2681 *skipped = 1;
2682 return max_sector - sector_nr;
2683 }
2684 /* before building a request, check if we can skip these blocks..
2685 * This call the bitmap_start_sync doesn't actually record anything
2686 */
2687 if (!md_bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, 1) &&
2688 !conf->fullsync && !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) {
2689 /* We can skip this block, and probably several more */
2690 *skipped = 1;
2691 return sync_blocks;
2692 }
2693
2694 /*
2695 * If there is non-resync activity waiting for a turn, then let it
2696 * though before starting on this new sync request.
2697 */
2698 if (atomic_read(&conf->nr_waiting[idx]))
2699 schedule_timeout_uninterruptible(1);
2700
2701 /* we are incrementing sector_nr below. To be safe, we check against
2702 * sector_nr + two times RESYNC_SECTORS
2703 */
2704
2705 md_bitmap_cond_end_sync(mddev->bitmap, sector_nr,
2706 mddev_is_clustered(mddev) && (sector_nr + 2 * RESYNC_SECTORS > conf->cluster_sync_high));
2707
2708
2709 if (raise_barrier(conf, sector_nr))
2710 return 0;
2711
2712 r1_bio = raid1_alloc_init_r1buf(conf);
2713
2714 rcu_read_lock();
2715 /*
2716 * If we get a correctably read error during resync or recovery,
2717 * we might want to read from a different device. So we
2718 * flag all drives that could conceivably be read from for READ,
2719 * and any others (which will be non-In_sync devices) for WRITE.
2720 * If a read fails, we try reading from something else for which READ
2721 * is OK.
2722 */
2723
2724 r1_bio->mddev = mddev;
2725 r1_bio->sector = sector_nr;
2726 r1_bio->state = 0;
2727 set_bit(R1BIO_IsSync, &r1_bio->state);
2728 /* make sure good_sectors won't go across barrier unit boundary */
2729 good_sectors = align_to_barrier_unit_end(sector_nr, good_sectors);
2730
2731 for (i = 0; i < conf->raid_disks * 2; i++) {
2732 struct md_rdev *rdev;
2733 bio = r1_bio->bios[i];
2734
2735 rdev = rcu_dereference(conf->mirrors[i].rdev);
2736 if (rdev == NULL ||
2737 test_bit(Faulty, &rdev->flags)) {
2738 if (i < conf->raid_disks)
2739 still_degraded = 1;
2740 } else if (!test_bit(In_sync, &rdev->flags)) {
2741 bio_set_op_attrs(bio, REQ_OP_WRITE, 0);
2742 bio->bi_end_io = end_sync_write;
2743 write_targets ++;
2744 } else {
2745 /* may need to read from here */
2746 sector_t first_bad = MaxSector;
2747 int bad_sectors;
2748
2749 if (is_badblock(rdev, sector_nr, good_sectors,
2750 &first_bad, &bad_sectors)) {
2751 if (first_bad > sector_nr)
2752 good_sectors = first_bad - sector_nr;
2753 else {
2754 bad_sectors -= (sector_nr - first_bad);
2755 if (min_bad == 0 ||
2756 min_bad > bad_sectors)
2757 min_bad = bad_sectors;
2758 }
2759 }
2760 if (sector_nr < first_bad) {
2761 if (test_bit(WriteMostly, &rdev->flags)) {
2762 if (wonly < 0)
2763 wonly = i;
2764 } else {
2765 if (disk < 0)
2766 disk = i;
2767 }
2768 bio_set_op_attrs(bio, REQ_OP_READ, 0);
2769 bio->bi_end_io = end_sync_read;
2770 read_targets++;
2771 } else if (!test_bit(WriteErrorSeen, &rdev->flags) &&
2772 test_bit(MD_RECOVERY_SYNC, &mddev->recovery) &&
2773 !test_bit(MD_RECOVERY_CHECK, &mddev->recovery)) {
2774 /*
2775 * The device is suitable for reading (InSync),
2776 * but has bad block(s) here. Let's try to correct them,
2777 * if we are doing resync or repair. Otherwise, leave
2778 * this device alone for this sync request.
2779 */
2780 bio_set_op_attrs(bio, REQ_OP_WRITE, 0);
2781 bio->bi_end_io = end_sync_write;
2782 write_targets++;
2783 }
2784 }
2785 if (bio->bi_end_io) {
2786 atomic_inc(&rdev->nr_pending);
2787 bio->bi_iter.bi_sector = sector_nr + rdev->data_offset;
2788 bio_set_dev(bio, rdev->bdev);
2789 if (test_bit(FailFast, &rdev->flags))
2790 bio->bi_opf |= MD_FAILFAST;
2791 }
2792 }
2793 rcu_read_unlock();
2794 if (disk < 0)
2795 disk = wonly;
2796 r1_bio->read_disk = disk;
2797
2798 if (read_targets == 0 && min_bad > 0) {
2799 /* These sectors are bad on all InSync devices, so we
2800 * need to mark them bad on all write targets
2801 */
2802 int ok = 1;
2803 for (i = 0 ; i < conf->raid_disks * 2 ; i++)
2804 if (r1_bio->bios[i]->bi_end_io == end_sync_write) {
2805 struct md_rdev *rdev = conf->mirrors[i].rdev;
2806 ok = rdev_set_badblocks(rdev, sector_nr,
2807 min_bad, 0
2808 ) && ok;
2809 }
2810 set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
2811 *skipped = 1;
2812 put_buf(r1_bio);
2813
2814 if (!ok) {
2815 /* Cannot record the badblocks, so need to
2816 * abort the resync.
2817 * If there are multiple read targets, could just
2818 * fail the really bad ones ???
2819 */
2820 conf->recovery_disabled = mddev->recovery_disabled;
2821 set_bit(MD_RECOVERY_INTR, &mddev->recovery);
2822 return 0;
2823 } else
2824 return min_bad;
2825
2826 }
2827 if (min_bad > 0 && min_bad < good_sectors) {
2828 /* only resync enough to reach the next bad->good
2829 * transition */
2830 good_sectors = min_bad;
2831 }
2832
2833 if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) && read_targets > 0)
2834 /* extra read targets are also write targets */
2835 write_targets += read_targets-1;
2836
2837 if (write_targets == 0 || read_targets == 0) {
2838 /* There is nowhere to write, so all non-sync
2839 * drives must be failed - so we are finished
2840 */
2841 sector_t rv;
2842 if (min_bad > 0)
2843 max_sector = sector_nr + min_bad;
2844 rv = max_sector - sector_nr;
2845 *skipped = 1;
2846 put_buf(r1_bio);
2847 return rv;
2848 }
2849
2850 if (max_sector > mddev->resync_max)
2851 max_sector = mddev->resync_max; /* Don't do IO beyond here */
2852 if (max_sector > sector_nr + good_sectors)
2853 max_sector = sector_nr + good_sectors;
2854 nr_sectors = 0;
2855 sync_blocks = 0;
2856 do {
2857 struct page *page;
2858 int len = PAGE_SIZE;
2859 if (sector_nr + (len>>9) > max_sector)
2860 len = (max_sector - sector_nr) << 9;
2861 if (len == 0)
2862 break;
2863 if (sync_blocks == 0) {
2864 if (!md_bitmap_start_sync(mddev->bitmap, sector_nr,
2865 &sync_blocks, still_degraded) &&
2866 !conf->fullsync &&
2867 !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
2868 break;
2869 if ((len >> 9) > sync_blocks)
2870 len = sync_blocks<<9;
2871 }
2872
2873 for (i = 0 ; i < conf->raid_disks * 2; i++) {
2874 struct resync_pages *rp;
2875
2876 bio = r1_bio->bios[i];
2877 rp = get_resync_pages(bio);
2878 if (bio->bi_end_io) {
2879 page = resync_fetch_page(rp, page_idx);
2880
2881 /*
2882 * won't fail because the vec table is big
2883 * enough to hold all these pages
2884 */
2885 bio_add_page(bio, page, len, 0);
2886 }
2887 }
2888 nr_sectors += len>>9;
2889 sector_nr += len>>9;
2890 sync_blocks -= (len>>9);
2891 } while (++page_idx < RESYNC_PAGES);
2892
2893 r1_bio->sectors = nr_sectors;
2894
2895 if (mddev_is_clustered(mddev) &&
2896 conf->cluster_sync_high < sector_nr + nr_sectors) {
2897 conf->cluster_sync_low = mddev->curr_resync_completed;
2898 conf->cluster_sync_high = conf->cluster_sync_low + CLUSTER_RESYNC_WINDOW_SECTORS;
2899 /* Send resync message */
2900 md_cluster_ops->resync_info_update(mddev,
2901 conf->cluster_sync_low,
2902 conf->cluster_sync_high);
2903 }
2904
2905 /* For a user-requested sync, we read all readable devices and do a
2906 * compare
2907 */
2908 if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) {
2909 atomic_set(&r1_bio->remaining, read_targets);
2910 for (i = 0; i < conf->raid_disks * 2 && read_targets; i++) {
2911 bio = r1_bio->bios[i];
2912 if (bio->bi_end_io == end_sync_read) {
2913 read_targets--;
2914 md_sync_acct_bio(bio, nr_sectors);
2915 if (read_targets == 1)
2916 bio->bi_opf &= ~MD_FAILFAST;
2917 generic_make_request(bio);
2918 }
2919 }
2920 } else {
2921 atomic_set(&r1_bio->remaining, 1);
2922 bio = r1_bio->bios[r1_bio->read_disk];
2923 md_sync_acct_bio(bio, nr_sectors);
2924 if (read_targets == 1)
2925 bio->bi_opf &= ~MD_FAILFAST;
2926 generic_make_request(bio);
2927 }
2928 return nr_sectors;
2929}
2930
2931static sector_t raid1_size(struct mddev *mddev, sector_t sectors, int raid_disks)
2932{
2933 if (sectors)
2934 return sectors;
2935
2936 return mddev->dev_sectors;
2937}
2938
2939static struct r1conf *setup_conf(struct mddev *mddev)
2940{
2941 struct r1conf *conf;
2942 int i;
2943 struct raid1_info *disk;
2944 struct md_rdev *rdev;
2945 int err = -ENOMEM;
2946
2947 conf = kzalloc(sizeof(struct r1conf), GFP_KERNEL);
2948 if (!conf)
2949 goto abort;
2950
2951 conf->nr_pending = kcalloc(BARRIER_BUCKETS_NR,
2952 sizeof(atomic_t), GFP_KERNEL);
2953 if (!conf->nr_pending)
2954 goto abort;
2955
2956 conf->nr_waiting = kcalloc(BARRIER_BUCKETS_NR,
2957 sizeof(atomic_t), GFP_KERNEL);
2958 if (!conf->nr_waiting)
2959 goto abort;
2960
2961 conf->nr_queued = kcalloc(BARRIER_BUCKETS_NR,
2962 sizeof(atomic_t), GFP_KERNEL);
2963 if (!conf->nr_queued)
2964 goto abort;
2965
2966 conf->barrier = kcalloc(BARRIER_BUCKETS_NR,
2967 sizeof(atomic_t), GFP_KERNEL);
2968 if (!conf->barrier)
2969 goto abort;
2970
2971 conf->mirrors = kzalloc(array3_size(sizeof(struct raid1_info),
2972 mddev->raid_disks, 2),
2973 GFP_KERNEL);
2974 if (!conf->mirrors)
2975 goto abort;
2976
2977 conf->tmppage = alloc_page(GFP_KERNEL);
2978 if (!conf->tmppage)
2979 goto abort;
2980
2981 conf->poolinfo = kzalloc(sizeof(*conf->poolinfo), GFP_KERNEL);
2982 if (!conf->poolinfo)
2983 goto abort;
2984 conf->poolinfo->raid_disks = mddev->raid_disks * 2;
2985 err = mempool_init(&conf->r1bio_pool, NR_RAID_BIOS, r1bio_pool_alloc,
2986 rbio_pool_free, conf->poolinfo);
2987 if (err)
2988 goto abort;
2989
2990 err = bioset_init(&conf->bio_split, BIO_POOL_SIZE, 0, 0);
2991 if (err)
2992 goto abort;
2993
2994 conf->poolinfo->mddev = mddev;
2995
2996 err = -EINVAL;
2997 spin_lock_init(&conf->device_lock);
2998 rdev_for_each(rdev, mddev) {
2999 int disk_idx = rdev->raid_disk;
3000 if (disk_idx >= mddev->raid_disks
3001 || disk_idx < 0)
3002 continue;
3003 if (test_bit(Replacement, &rdev->flags))
3004 disk = conf->mirrors + mddev->raid_disks + disk_idx;
3005 else
3006 disk = conf->mirrors + disk_idx;
3007
3008 if (disk->rdev)
3009 goto abort;
3010 disk->rdev = rdev;
3011 disk->head_position = 0;
3012 disk->seq_start = MaxSector;
3013 }
3014 conf->raid_disks = mddev->raid_disks;
3015 conf->mddev = mddev;
3016 INIT_LIST_HEAD(&conf->retry_list);
3017 INIT_LIST_HEAD(&conf->bio_end_io_list);
3018
3019 spin_lock_init(&conf->resync_lock);
3020 init_waitqueue_head(&conf->wait_barrier);
3021
3022 bio_list_init(&conf->pending_bio_list);
3023 conf->pending_count = 0;
3024 conf->recovery_disabled = mddev->recovery_disabled - 1;
3025
3026 err = -EIO;
3027 for (i = 0; i < conf->raid_disks * 2; i++) {
3028
3029 disk = conf->mirrors + i;
3030
3031 if (i < conf->raid_disks &&
3032 disk[conf->raid_disks].rdev) {
3033 /* This slot has a replacement. */
3034 if (!disk->rdev) {
3035 /* No original, just make the replacement
3036 * a recovering spare
3037 */
3038 disk->rdev =
3039 disk[conf->raid_disks].rdev;
3040 disk[conf->raid_disks].rdev = NULL;
3041 } else if (!test_bit(In_sync, &disk->rdev->flags))
3042 /* Original is not in_sync - bad */
3043 goto abort;
3044 }
3045
3046 if (!disk->rdev ||
3047 !test_bit(In_sync, &disk->rdev->flags)) {
3048 disk->head_position = 0;
3049 if (disk->rdev &&
3050 (disk->rdev->saved_raid_disk < 0))
3051 conf->fullsync = 1;
3052 }
3053 }
3054
3055 err = -ENOMEM;
3056 conf->thread = md_register_thread(raid1d, mddev, "raid1");
3057 if (!conf->thread)
3058 goto abort;
3059
3060 return conf;
3061
3062 abort:
3063 if (conf) {
3064 mempool_exit(&conf->r1bio_pool);
3065 kfree(conf->mirrors);
3066 safe_put_page(conf->tmppage);
3067 kfree(conf->poolinfo);
3068 kfree(conf->nr_pending);
3069 kfree(conf->nr_waiting);
3070 kfree(conf->nr_queued);
3071 kfree(conf->barrier);
3072 bioset_exit(&conf->bio_split);
3073 kfree(conf);
3074 }
3075 return ERR_PTR(err);
3076}
3077
3078static void raid1_free(struct mddev *mddev, void *priv);
3079static int raid1_run(struct mddev *mddev)
3080{
3081 struct r1conf *conf;
3082 int i;
3083 struct md_rdev *rdev;
3084 int ret;
3085 bool discard_supported = false;
3086
3087 if (mddev->level != 1) {
3088 pr_warn("md/raid1:%s: raid level not set to mirroring (%d)\n",
3089 mdname(mddev), mddev->level);
3090 return -EIO;
3091 }
3092 if (mddev->reshape_position != MaxSector) {
3093 pr_warn("md/raid1:%s: reshape_position set but not supported\n",
3094 mdname(mddev));
3095 return -EIO;
3096 }
3097 if (mddev_init_writes_pending(mddev) < 0)
3098 return -ENOMEM;
3099 /*
3100 * copy the already verified devices into our private RAID1
3101 * bookkeeping area. [whatever we allocate in run(),
3102 * should be freed in raid1_free()]
3103 */
3104 if (mddev->private == NULL)
3105 conf = setup_conf(mddev);
3106 else
3107 conf = mddev->private;
3108
3109 if (IS_ERR(conf))
3110 return PTR_ERR(conf);
3111
3112 if (mddev->queue) {
3113 blk_queue_max_write_same_sectors(mddev->queue, 0);
3114 blk_queue_max_write_zeroes_sectors(mddev->queue, 0);
3115 }
3116
3117 rdev_for_each(rdev, mddev) {
3118 if (!mddev->gendisk)
3119 continue;
3120 disk_stack_limits(mddev->gendisk, rdev->bdev,
3121 rdev->data_offset << 9);
3122 if (blk_queue_discard(bdev_get_queue(rdev->bdev)))
3123 discard_supported = true;
3124 }
3125
3126 mddev->degraded = 0;
3127 for (i = 0; i < conf->raid_disks; i++)
3128 if (conf->mirrors[i].rdev == NULL ||
3129 !test_bit(In_sync, &conf->mirrors[i].rdev->flags) ||
3130 test_bit(Faulty, &conf->mirrors[i].rdev->flags))
3131 mddev->degraded++;
3132 /*
3133 * RAID1 needs at least one disk in active
3134 */
3135 if (conf->raid_disks - mddev->degraded < 1) {
3136 ret = -EINVAL;
3137 goto abort;
3138 }
3139
3140 if (conf->raid_disks - mddev->degraded == 1)
3141 mddev->recovery_cp = MaxSector;
3142
3143 if (mddev->recovery_cp != MaxSector)
3144 pr_info("md/raid1:%s: not clean -- starting background reconstruction\n",
3145 mdname(mddev));
3146 pr_info("md/raid1:%s: active with %d out of %d mirrors\n",
3147 mdname(mddev), mddev->raid_disks - mddev->degraded,
3148 mddev->raid_disks);
3149
3150 /*
3151 * Ok, everything is just fine now
3152 */
3153 mddev->thread = conf->thread;
3154 conf->thread = NULL;
3155 mddev->private = conf;
3156 set_bit(MD_FAILFAST_SUPPORTED, &mddev->flags);
3157
3158 md_set_array_sectors(mddev, raid1_size(mddev, 0, 0));
3159
3160 if (mddev->queue) {
3161 if (discard_supported)
3162 blk_queue_flag_set(QUEUE_FLAG_DISCARD,
3163 mddev->queue);
3164 else
3165 blk_queue_flag_clear(QUEUE_FLAG_DISCARD,
3166 mddev->queue);
3167 }
3168
3169 ret = md_integrity_register(mddev);
3170 if (ret) {
3171 md_unregister_thread(&mddev->thread);
3172 goto abort;
3173 }
3174 return 0;
3175
3176abort:
3177 raid1_free(mddev, conf);
3178 return ret;
3179}
3180
3181static void raid1_free(struct mddev *mddev, void *priv)
3182{
3183 struct r1conf *conf = priv;
3184
3185 mempool_exit(&conf->r1bio_pool);
3186 kfree(conf->mirrors);
3187 safe_put_page(conf->tmppage);
3188 kfree(conf->poolinfo);
3189 kfree(conf->nr_pending);
3190 kfree(conf->nr_waiting);
3191 kfree(conf->nr_queued);
3192 kfree(conf->barrier);
3193 bioset_exit(&conf->bio_split);
3194 kfree(conf);
3195}
3196
3197static int raid1_resize(struct mddev *mddev, sector_t sectors)
3198{
3199 /* no resync is happening, and there is enough space
3200 * on all devices, so we can resize.
3201 * We need to make sure resync covers any new space.
3202 * If the array is shrinking we should possibly wait until
3203 * any io in the removed space completes, but it hardly seems
3204 * worth it.
3205 */
3206 sector_t newsize = raid1_size(mddev, sectors, 0);
3207 if (mddev->external_size &&
3208 mddev->array_sectors > newsize)
3209 return -EINVAL;
3210 if (mddev->bitmap) {
3211 int ret = md_bitmap_resize(mddev->bitmap, newsize, 0, 0);
3212 if (ret)
3213 return ret;
3214 }
3215 md_set_array_sectors(mddev, newsize);
3216 if (sectors > mddev->dev_sectors &&
3217 mddev->recovery_cp > mddev->dev_sectors) {
3218 mddev->recovery_cp = mddev->dev_sectors;
3219 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3220 }
3221 mddev->dev_sectors = sectors;
3222 mddev->resync_max_sectors = sectors;
3223 return 0;
3224}
3225
3226static int raid1_reshape(struct mddev *mddev)
3227{
3228 /* We need to:
3229 * 1/ resize the r1bio_pool
3230 * 2/ resize conf->mirrors
3231 *
3232 * We allocate a new r1bio_pool if we can.
3233 * Then raise a device barrier and wait until all IO stops.
3234 * Then resize conf->mirrors and swap in the new r1bio pool.
3235 *
3236 * At the same time, we "pack" the devices so that all the missing
3237 * devices have the higher raid_disk numbers.
3238 */
3239 mempool_t newpool, oldpool;
3240 struct pool_info *newpoolinfo;
3241 struct raid1_info *newmirrors;
3242 struct r1conf *conf = mddev->private;
3243 int cnt, raid_disks;
3244 unsigned long flags;
3245 int d, d2;
3246 int ret;
3247
3248 memset(&newpool, 0, sizeof(newpool));
3249 memset(&oldpool, 0, sizeof(oldpool));
3250
3251 /* Cannot change chunk_size, layout, or level */
3252 if (mddev->chunk_sectors != mddev->new_chunk_sectors ||
3253 mddev->layout != mddev->new_layout ||
3254 mddev->level != mddev->new_level) {
3255 mddev->new_chunk_sectors = mddev->chunk_sectors;
3256 mddev->new_layout = mddev->layout;
3257 mddev->new_level = mddev->level;
3258 return -EINVAL;
3259 }
3260
3261 if (!mddev_is_clustered(mddev))
3262 md_allow_write(mddev);
3263
3264 raid_disks = mddev->raid_disks + mddev->delta_disks;
3265
3266 if (raid_disks < conf->raid_disks) {
3267 cnt=0;
3268 for (d= 0; d < conf->raid_disks; d++)
3269 if (conf->mirrors[d].rdev)
3270 cnt++;
3271 if (cnt > raid_disks)
3272 return -EBUSY;
3273 }
3274
3275 newpoolinfo = kmalloc(sizeof(*newpoolinfo), GFP_KERNEL);
3276 if (!newpoolinfo)
3277 return -ENOMEM;
3278 newpoolinfo->mddev = mddev;
3279 newpoolinfo->raid_disks = raid_disks * 2;
3280
3281 ret = mempool_init(&newpool, NR_RAID_BIOS, r1bio_pool_alloc,
3282 rbio_pool_free, newpoolinfo);
3283 if (ret) {
3284 kfree(newpoolinfo);
3285 return ret;
3286 }
3287 newmirrors = kzalloc(array3_size(sizeof(struct raid1_info),
3288 raid_disks, 2),
3289 GFP_KERNEL);
3290 if (!newmirrors) {
3291 kfree(newpoolinfo);
3292 mempool_exit(&newpool);
3293 return -ENOMEM;
3294 }
3295
3296 freeze_array(conf, 0);
3297
3298 /* ok, everything is stopped */
3299 oldpool = conf->r1bio_pool;
3300 conf->r1bio_pool = newpool;
3301
3302 for (d = d2 = 0; d < conf->raid_disks; d++) {
3303 struct md_rdev *rdev = conf->mirrors[d].rdev;
3304 if (rdev && rdev->raid_disk != d2) {
3305 sysfs_unlink_rdev(mddev, rdev);
3306 rdev->raid_disk = d2;
3307 sysfs_unlink_rdev(mddev, rdev);
3308 if (sysfs_link_rdev(mddev, rdev))
3309 pr_warn("md/raid1:%s: cannot register rd%d\n",
3310 mdname(mddev), rdev->raid_disk);
3311 }
3312 if (rdev)
3313 newmirrors[d2++].rdev = rdev;
3314 }
3315 kfree(conf->mirrors);
3316 conf->mirrors = newmirrors;
3317 kfree(conf->poolinfo);
3318 conf->poolinfo = newpoolinfo;
3319
3320 spin_lock_irqsave(&conf->device_lock, flags);
3321 mddev->degraded += (raid_disks - conf->raid_disks);
3322 spin_unlock_irqrestore(&conf->device_lock, flags);
3323 conf->raid_disks = mddev->raid_disks = raid_disks;
3324 mddev->delta_disks = 0;
3325
3326 unfreeze_array(conf);
3327
3328 set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
3329 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3330 md_wakeup_thread(mddev->thread);
3331
3332 mempool_exit(&oldpool);
3333 return 0;
3334}
3335
3336static void raid1_quiesce(struct mddev *mddev, int quiesce)
3337{
3338 struct r1conf *conf = mddev->private;
3339
3340 if (quiesce)
3341 freeze_array(conf, 0);
3342 else
3343 unfreeze_array(conf);
3344}
3345
3346static void *raid1_takeover(struct mddev *mddev)
3347{
3348 /* raid1 can take over:
3349 * raid5 with 2 devices, any layout or chunk size
3350 */
3351 if (mddev->level == 5 && mddev->raid_disks == 2) {
3352 struct r1conf *conf;
3353 mddev->new_level = 1;
3354 mddev->new_layout = 0;
3355 mddev->new_chunk_sectors = 0;
3356 conf = setup_conf(mddev);
3357 if (!IS_ERR(conf)) {
3358 /* Array must appear to be quiesced */
3359 conf->array_frozen = 1;
3360 mddev_clear_unsupported_flags(mddev,
3361 UNSUPPORTED_MDDEV_FLAGS);
3362 }
3363 return conf;
3364 }
3365 return ERR_PTR(-EINVAL);
3366}
3367
3368static struct md_personality raid1_personality =
3369{
3370 .name = "raid1",
3371 .level = 1,
3372 .owner = THIS_MODULE,
3373 .make_request = raid1_make_request,
3374 .run = raid1_run,
3375 .free = raid1_free,
3376 .status = raid1_status,
3377 .error_handler = raid1_error,
3378 .hot_add_disk = raid1_add_disk,
3379 .hot_remove_disk= raid1_remove_disk,
3380 .spare_active = raid1_spare_active,
3381 .sync_request = raid1_sync_request,
3382 .resize = raid1_resize,
3383 .size = raid1_size,
3384 .check_reshape = raid1_reshape,
3385 .quiesce = raid1_quiesce,
3386 .takeover = raid1_takeover,
3387 .congested = raid1_congested,
3388};
3389
3390static int __init raid_init(void)
3391{
3392 return register_md_personality(&raid1_personality);
3393}
3394
3395static void raid_exit(void)
3396{
3397 unregister_md_personality(&raid1_personality);
3398}
3399
3400module_init(raid_init);
3401module_exit(raid_exit);
3402MODULE_LICENSE("GPL");
3403MODULE_DESCRIPTION("RAID1 (mirroring) personality for MD");
3404MODULE_ALIAS("md-personality-3"); /* RAID1 */
3405MODULE_ALIAS("md-raid1");
3406MODULE_ALIAS("md-level-1");
3407
3408module_param(max_queued_requests, int, S_IRUGO|S_IWUSR);
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * raid1.c : Multiple Devices driver for Linux
4 *
5 * Copyright (C) 1999, 2000, 2001 Ingo Molnar, Red Hat
6 *
7 * Copyright (C) 1996, 1997, 1998 Ingo Molnar, Miguel de Icaza, Gadi Oxman
8 *
9 * RAID-1 management functions.
10 *
11 * Better read-balancing code written by Mika Kuoppala <miku@iki.fi>, 2000
12 *
13 * Fixes to reconstruction by Jakob Østergaard" <jakob@ostenfeld.dk>
14 * Various fixes by Neil Brown <neilb@cse.unsw.edu.au>
15 *
16 * Changes by Peter T. Breuer <ptb@it.uc3m.es> 31/1/2003 to support
17 * bitmapped intelligence in resync:
18 *
19 * - bitmap marked during normal i/o
20 * - bitmap used to skip nondirty blocks during sync
21 *
22 * Additions to bitmap code, (C) 2003-2004 Paul Clements, SteelEye Technology:
23 * - persistent bitmap code
24 */
25
26#include <linux/slab.h>
27#include <linux/delay.h>
28#include <linux/blkdev.h>
29#include <linux/module.h>
30#include <linux/seq_file.h>
31#include <linux/ratelimit.h>
32#include <linux/interval_tree_generic.h>
33
34#include <trace/events/block.h>
35
36#include "md.h"
37#include "raid1.h"
38#include "md-bitmap.h"
39
40#define UNSUPPORTED_MDDEV_FLAGS \
41 ((1L << MD_HAS_JOURNAL) | \
42 (1L << MD_JOURNAL_CLEAN) | \
43 (1L << MD_HAS_PPL) | \
44 (1L << MD_HAS_MULTIPLE_PPLS))
45
46static void allow_barrier(struct r1conf *conf, sector_t sector_nr);
47static void lower_barrier(struct r1conf *conf, sector_t sector_nr);
48
49#define raid1_log(md, fmt, args...) \
50 do { if ((md)->queue) blk_add_trace_msg((md)->queue, "raid1 " fmt, ##args); } while (0)
51
52#include "raid1-10.c"
53
54#define START(node) ((node)->start)
55#define LAST(node) ((node)->last)
56INTERVAL_TREE_DEFINE(struct serial_info, node, sector_t, _subtree_last,
57 START, LAST, static inline, raid1_rb);
58
59static int check_and_add_serial(struct md_rdev *rdev, struct r1bio *r1_bio,
60 struct serial_info *si, int idx)
61{
62 unsigned long flags;
63 int ret = 0;
64 sector_t lo = r1_bio->sector;
65 sector_t hi = lo + r1_bio->sectors;
66 struct serial_in_rdev *serial = &rdev->serial[idx];
67
68 spin_lock_irqsave(&serial->serial_lock, flags);
69 /* collision happened */
70 if (raid1_rb_iter_first(&serial->serial_rb, lo, hi))
71 ret = -EBUSY;
72 else {
73 si->start = lo;
74 si->last = hi;
75 raid1_rb_insert(si, &serial->serial_rb);
76 }
77 spin_unlock_irqrestore(&serial->serial_lock, flags);
78
79 return ret;
80}
81
82static void wait_for_serialization(struct md_rdev *rdev, struct r1bio *r1_bio)
83{
84 struct mddev *mddev = rdev->mddev;
85 struct serial_info *si;
86 int idx = sector_to_idx(r1_bio->sector);
87 struct serial_in_rdev *serial = &rdev->serial[idx];
88
89 if (WARN_ON(!mddev->serial_info_pool))
90 return;
91 si = mempool_alloc(mddev->serial_info_pool, GFP_NOIO);
92 wait_event(serial->serial_io_wait,
93 check_and_add_serial(rdev, r1_bio, si, idx) == 0);
94}
95
96static void remove_serial(struct md_rdev *rdev, sector_t lo, sector_t hi)
97{
98 struct serial_info *si;
99 unsigned long flags;
100 int found = 0;
101 struct mddev *mddev = rdev->mddev;
102 int idx = sector_to_idx(lo);
103 struct serial_in_rdev *serial = &rdev->serial[idx];
104
105 spin_lock_irqsave(&serial->serial_lock, flags);
106 for (si = raid1_rb_iter_first(&serial->serial_rb, lo, hi);
107 si; si = raid1_rb_iter_next(si, lo, hi)) {
108 if (si->start == lo && si->last == hi) {
109 raid1_rb_remove(si, &serial->serial_rb);
110 mempool_free(si, mddev->serial_info_pool);
111 found = 1;
112 break;
113 }
114 }
115 if (!found)
116 WARN(1, "The write IO is not recorded for serialization\n");
117 spin_unlock_irqrestore(&serial->serial_lock, flags);
118 wake_up(&serial->serial_io_wait);
119}
120
121/*
122 * for resync bio, r1bio pointer can be retrieved from the per-bio
123 * 'struct resync_pages'.
124 */
125static inline struct r1bio *get_resync_r1bio(struct bio *bio)
126{
127 return get_resync_pages(bio)->raid_bio;
128}
129
130static void * r1bio_pool_alloc(gfp_t gfp_flags, void *data)
131{
132 struct pool_info *pi = data;
133 int size = offsetof(struct r1bio, bios[pi->raid_disks]);
134
135 /* allocate a r1bio with room for raid_disks entries in the bios array */
136 return kzalloc(size, gfp_flags);
137}
138
139#define RESYNC_DEPTH 32
140#define RESYNC_SECTORS (RESYNC_BLOCK_SIZE >> 9)
141#define RESYNC_WINDOW (RESYNC_BLOCK_SIZE * RESYNC_DEPTH)
142#define RESYNC_WINDOW_SECTORS (RESYNC_WINDOW >> 9)
143#define CLUSTER_RESYNC_WINDOW (16 * RESYNC_WINDOW)
144#define CLUSTER_RESYNC_WINDOW_SECTORS (CLUSTER_RESYNC_WINDOW >> 9)
145
146static void * r1buf_pool_alloc(gfp_t gfp_flags, void *data)
147{
148 struct pool_info *pi = data;
149 struct r1bio *r1_bio;
150 struct bio *bio;
151 int need_pages;
152 int j;
153 struct resync_pages *rps;
154
155 r1_bio = r1bio_pool_alloc(gfp_flags, pi);
156 if (!r1_bio)
157 return NULL;
158
159 rps = kmalloc_array(pi->raid_disks, sizeof(struct resync_pages),
160 gfp_flags);
161 if (!rps)
162 goto out_free_r1bio;
163
164 /*
165 * Allocate bios : 1 for reading, n-1 for writing
166 */
167 for (j = pi->raid_disks ; j-- ; ) {
168 bio = bio_kmalloc(gfp_flags, RESYNC_PAGES);
169 if (!bio)
170 goto out_free_bio;
171 r1_bio->bios[j] = bio;
172 }
173 /*
174 * Allocate RESYNC_PAGES data pages and attach them to
175 * the first bio.
176 * If this is a user-requested check/repair, allocate
177 * RESYNC_PAGES for each bio.
178 */
179 if (test_bit(MD_RECOVERY_REQUESTED, &pi->mddev->recovery))
180 need_pages = pi->raid_disks;
181 else
182 need_pages = 1;
183 for (j = 0; j < pi->raid_disks; j++) {
184 struct resync_pages *rp = &rps[j];
185
186 bio = r1_bio->bios[j];
187
188 if (j < need_pages) {
189 if (resync_alloc_pages(rp, gfp_flags))
190 goto out_free_pages;
191 } else {
192 memcpy(rp, &rps[0], sizeof(*rp));
193 resync_get_all_pages(rp);
194 }
195
196 rp->raid_bio = r1_bio;
197 bio->bi_private = rp;
198 }
199
200 r1_bio->master_bio = NULL;
201
202 return r1_bio;
203
204out_free_pages:
205 while (--j >= 0)
206 resync_free_pages(&rps[j]);
207
208out_free_bio:
209 while (++j < pi->raid_disks)
210 bio_put(r1_bio->bios[j]);
211 kfree(rps);
212
213out_free_r1bio:
214 rbio_pool_free(r1_bio, data);
215 return NULL;
216}
217
218static void r1buf_pool_free(void *__r1_bio, void *data)
219{
220 struct pool_info *pi = data;
221 int i;
222 struct r1bio *r1bio = __r1_bio;
223 struct resync_pages *rp = NULL;
224
225 for (i = pi->raid_disks; i--; ) {
226 rp = get_resync_pages(r1bio->bios[i]);
227 resync_free_pages(rp);
228 bio_put(r1bio->bios[i]);
229 }
230
231 /* resync pages array stored in the 1st bio's .bi_private */
232 kfree(rp);
233
234 rbio_pool_free(r1bio, data);
235}
236
237static void put_all_bios(struct r1conf *conf, struct r1bio *r1_bio)
238{
239 int i;
240
241 for (i = 0; i < conf->raid_disks * 2; i++) {
242 struct bio **bio = r1_bio->bios + i;
243 if (!BIO_SPECIAL(*bio))
244 bio_put(*bio);
245 *bio = NULL;
246 }
247}
248
249static void free_r1bio(struct r1bio *r1_bio)
250{
251 struct r1conf *conf = r1_bio->mddev->private;
252
253 put_all_bios(conf, r1_bio);
254 mempool_free(r1_bio, &conf->r1bio_pool);
255}
256
257static void put_buf(struct r1bio *r1_bio)
258{
259 struct r1conf *conf = r1_bio->mddev->private;
260 sector_t sect = r1_bio->sector;
261 int i;
262
263 for (i = 0; i < conf->raid_disks * 2; i++) {
264 struct bio *bio = r1_bio->bios[i];
265 if (bio->bi_end_io)
266 rdev_dec_pending(conf->mirrors[i].rdev, r1_bio->mddev);
267 }
268
269 mempool_free(r1_bio, &conf->r1buf_pool);
270
271 lower_barrier(conf, sect);
272}
273
274static void reschedule_retry(struct r1bio *r1_bio)
275{
276 unsigned long flags;
277 struct mddev *mddev = r1_bio->mddev;
278 struct r1conf *conf = mddev->private;
279 int idx;
280
281 idx = sector_to_idx(r1_bio->sector);
282 spin_lock_irqsave(&conf->device_lock, flags);
283 list_add(&r1_bio->retry_list, &conf->retry_list);
284 atomic_inc(&conf->nr_queued[idx]);
285 spin_unlock_irqrestore(&conf->device_lock, flags);
286
287 wake_up(&conf->wait_barrier);
288 md_wakeup_thread(mddev->thread);
289}
290
291/*
292 * raid_end_bio_io() is called when we have finished servicing a mirrored
293 * operation and are ready to return a success/failure code to the buffer
294 * cache layer.
295 */
296static void call_bio_endio(struct r1bio *r1_bio)
297{
298 struct bio *bio = r1_bio->master_bio;
299
300 if (!test_bit(R1BIO_Uptodate, &r1_bio->state))
301 bio->bi_status = BLK_STS_IOERR;
302
303 if (blk_queue_io_stat(bio->bi_bdev->bd_disk->queue))
304 bio_end_io_acct(bio, r1_bio->start_time);
305 bio_endio(bio);
306}
307
308static void raid_end_bio_io(struct r1bio *r1_bio)
309{
310 struct bio *bio = r1_bio->master_bio;
311 struct r1conf *conf = r1_bio->mddev->private;
312
313 /* if nobody has done the final endio yet, do it now */
314 if (!test_and_set_bit(R1BIO_Returned, &r1_bio->state)) {
315 pr_debug("raid1: sync end %s on sectors %llu-%llu\n",
316 (bio_data_dir(bio) == WRITE) ? "write" : "read",
317 (unsigned long long) bio->bi_iter.bi_sector,
318 (unsigned long long) bio_end_sector(bio) - 1);
319
320 call_bio_endio(r1_bio);
321 }
322 /*
323 * Wake up any possible resync thread that waits for the device
324 * to go idle. All I/Os, even write-behind writes, are done.
325 */
326 allow_barrier(conf, r1_bio->sector);
327
328 free_r1bio(r1_bio);
329}
330
331/*
332 * Update disk head position estimator based on IRQ completion info.
333 */
334static inline void update_head_pos(int disk, struct r1bio *r1_bio)
335{
336 struct r1conf *conf = r1_bio->mddev->private;
337
338 conf->mirrors[disk].head_position =
339 r1_bio->sector + (r1_bio->sectors);
340}
341
342/*
343 * Find the disk number which triggered given bio
344 */
345static int find_bio_disk(struct r1bio *r1_bio, struct bio *bio)
346{
347 int mirror;
348 struct r1conf *conf = r1_bio->mddev->private;
349 int raid_disks = conf->raid_disks;
350
351 for (mirror = 0; mirror < raid_disks * 2; mirror++)
352 if (r1_bio->bios[mirror] == bio)
353 break;
354
355 BUG_ON(mirror == raid_disks * 2);
356 update_head_pos(mirror, r1_bio);
357
358 return mirror;
359}
360
361static void raid1_end_read_request(struct bio *bio)
362{
363 int uptodate = !bio->bi_status;
364 struct r1bio *r1_bio = bio->bi_private;
365 struct r1conf *conf = r1_bio->mddev->private;
366 struct md_rdev *rdev = conf->mirrors[r1_bio->read_disk].rdev;
367
368 /*
369 * this branch is our 'one mirror IO has finished' event handler:
370 */
371 update_head_pos(r1_bio->read_disk, r1_bio);
372
373 if (uptodate)
374 set_bit(R1BIO_Uptodate, &r1_bio->state);
375 else if (test_bit(FailFast, &rdev->flags) &&
376 test_bit(R1BIO_FailFast, &r1_bio->state))
377 /* This was a fail-fast read so we definitely
378 * want to retry */
379 ;
380 else {
381 /* If all other devices have failed, we want to return
382 * the error upwards rather than fail the last device.
383 * Here we redefine "uptodate" to mean "Don't want to retry"
384 */
385 unsigned long flags;
386 spin_lock_irqsave(&conf->device_lock, flags);
387 if (r1_bio->mddev->degraded == conf->raid_disks ||
388 (r1_bio->mddev->degraded == conf->raid_disks-1 &&
389 test_bit(In_sync, &rdev->flags)))
390 uptodate = 1;
391 spin_unlock_irqrestore(&conf->device_lock, flags);
392 }
393
394 if (uptodate) {
395 raid_end_bio_io(r1_bio);
396 rdev_dec_pending(rdev, conf->mddev);
397 } else {
398 /*
399 * oops, read error:
400 */
401 char b[BDEVNAME_SIZE];
402 pr_err_ratelimited("md/raid1:%s: %s: rescheduling sector %llu\n",
403 mdname(conf->mddev),
404 bdevname(rdev->bdev, b),
405 (unsigned long long)r1_bio->sector);
406 set_bit(R1BIO_ReadError, &r1_bio->state);
407 reschedule_retry(r1_bio);
408 /* don't drop the reference on read_disk yet */
409 }
410}
411
412static void close_write(struct r1bio *r1_bio)
413{
414 /* it really is the end of this request */
415 if (test_bit(R1BIO_BehindIO, &r1_bio->state)) {
416 bio_free_pages(r1_bio->behind_master_bio);
417 bio_put(r1_bio->behind_master_bio);
418 r1_bio->behind_master_bio = NULL;
419 }
420 /* clear the bitmap if all writes complete successfully */
421 md_bitmap_endwrite(r1_bio->mddev->bitmap, r1_bio->sector,
422 r1_bio->sectors,
423 !test_bit(R1BIO_Degraded, &r1_bio->state),
424 test_bit(R1BIO_BehindIO, &r1_bio->state));
425 md_write_end(r1_bio->mddev);
426}
427
428static void r1_bio_write_done(struct r1bio *r1_bio)
429{
430 if (!atomic_dec_and_test(&r1_bio->remaining))
431 return;
432
433 if (test_bit(R1BIO_WriteError, &r1_bio->state))
434 reschedule_retry(r1_bio);
435 else {
436 close_write(r1_bio);
437 if (test_bit(R1BIO_MadeGood, &r1_bio->state))
438 reschedule_retry(r1_bio);
439 else
440 raid_end_bio_io(r1_bio);
441 }
442}
443
444static void raid1_end_write_request(struct bio *bio)
445{
446 struct r1bio *r1_bio = bio->bi_private;
447 int behind = test_bit(R1BIO_BehindIO, &r1_bio->state);
448 struct r1conf *conf = r1_bio->mddev->private;
449 struct bio *to_put = NULL;
450 int mirror = find_bio_disk(r1_bio, bio);
451 struct md_rdev *rdev = conf->mirrors[mirror].rdev;
452 bool discard_error;
453 sector_t lo = r1_bio->sector;
454 sector_t hi = r1_bio->sector + r1_bio->sectors;
455
456 discard_error = bio->bi_status && bio_op(bio) == REQ_OP_DISCARD;
457
458 /*
459 * 'one mirror IO has finished' event handler:
460 */
461 if (bio->bi_status && !discard_error) {
462 set_bit(WriteErrorSeen, &rdev->flags);
463 if (!test_and_set_bit(WantReplacement, &rdev->flags))
464 set_bit(MD_RECOVERY_NEEDED, &
465 conf->mddev->recovery);
466
467 if (test_bit(FailFast, &rdev->flags) &&
468 (bio->bi_opf & MD_FAILFAST) &&
469 /* We never try FailFast to WriteMostly devices */
470 !test_bit(WriteMostly, &rdev->flags)) {
471 md_error(r1_bio->mddev, rdev);
472 }
473
474 /*
475 * When the device is faulty, it is not necessary to
476 * handle write error.
477 */
478 if (!test_bit(Faulty, &rdev->flags))
479 set_bit(R1BIO_WriteError, &r1_bio->state);
480 else {
481 /* Fail the request */
482 set_bit(R1BIO_Degraded, &r1_bio->state);
483 /* Finished with this branch */
484 r1_bio->bios[mirror] = NULL;
485 to_put = bio;
486 }
487 } else {
488 /*
489 * Set R1BIO_Uptodate in our master bio, so that we
490 * will return a good error code for to the higher
491 * levels even if IO on some other mirrored buffer
492 * fails.
493 *
494 * The 'master' represents the composite IO operation
495 * to user-side. So if something waits for IO, then it
496 * will wait for the 'master' bio.
497 */
498 sector_t first_bad;
499 int bad_sectors;
500
501 r1_bio->bios[mirror] = NULL;
502 to_put = bio;
503 /*
504 * Do not set R1BIO_Uptodate if the current device is
505 * rebuilding or Faulty. This is because we cannot use
506 * such device for properly reading the data back (we could
507 * potentially use it, if the current write would have felt
508 * before rdev->recovery_offset, but for simplicity we don't
509 * check this here.
510 */
511 if (test_bit(In_sync, &rdev->flags) &&
512 !test_bit(Faulty, &rdev->flags))
513 set_bit(R1BIO_Uptodate, &r1_bio->state);
514
515 /* Maybe we can clear some bad blocks. */
516 if (is_badblock(rdev, r1_bio->sector, r1_bio->sectors,
517 &first_bad, &bad_sectors) && !discard_error) {
518 r1_bio->bios[mirror] = IO_MADE_GOOD;
519 set_bit(R1BIO_MadeGood, &r1_bio->state);
520 }
521 }
522
523 if (behind) {
524 if (test_bit(CollisionCheck, &rdev->flags))
525 remove_serial(rdev, lo, hi);
526 if (test_bit(WriteMostly, &rdev->flags))
527 atomic_dec(&r1_bio->behind_remaining);
528
529 /*
530 * In behind mode, we ACK the master bio once the I/O
531 * has safely reached all non-writemostly
532 * disks. Setting the Returned bit ensures that this
533 * gets done only once -- we don't ever want to return
534 * -EIO here, instead we'll wait
535 */
536 if (atomic_read(&r1_bio->behind_remaining) >= (atomic_read(&r1_bio->remaining)-1) &&
537 test_bit(R1BIO_Uptodate, &r1_bio->state)) {
538 /* Maybe we can return now */
539 if (!test_and_set_bit(R1BIO_Returned, &r1_bio->state)) {
540 struct bio *mbio = r1_bio->master_bio;
541 pr_debug("raid1: behind end write sectors"
542 " %llu-%llu\n",
543 (unsigned long long) mbio->bi_iter.bi_sector,
544 (unsigned long long) bio_end_sector(mbio) - 1);
545 call_bio_endio(r1_bio);
546 }
547 }
548 } else if (rdev->mddev->serialize_policy)
549 remove_serial(rdev, lo, hi);
550 if (r1_bio->bios[mirror] == NULL)
551 rdev_dec_pending(rdev, conf->mddev);
552
553 /*
554 * Let's see if all mirrored write operations have finished
555 * already.
556 */
557 r1_bio_write_done(r1_bio);
558
559 if (to_put)
560 bio_put(to_put);
561}
562
563static sector_t align_to_barrier_unit_end(sector_t start_sector,
564 sector_t sectors)
565{
566 sector_t len;
567
568 WARN_ON(sectors == 0);
569 /*
570 * len is the number of sectors from start_sector to end of the
571 * barrier unit which start_sector belongs to.
572 */
573 len = round_up(start_sector + 1, BARRIER_UNIT_SECTOR_SIZE) -
574 start_sector;
575
576 if (len > sectors)
577 len = sectors;
578
579 return len;
580}
581
582/*
583 * This routine returns the disk from which the requested read should
584 * be done. There is a per-array 'next expected sequential IO' sector
585 * number - if this matches on the next IO then we use the last disk.
586 * There is also a per-disk 'last know head position' sector that is
587 * maintained from IRQ contexts, both the normal and the resync IO
588 * completion handlers update this position correctly. If there is no
589 * perfect sequential match then we pick the disk whose head is closest.
590 *
591 * If there are 2 mirrors in the same 2 devices, performance degrades
592 * because position is mirror, not device based.
593 *
594 * The rdev for the device selected will have nr_pending incremented.
595 */
596static int read_balance(struct r1conf *conf, struct r1bio *r1_bio, int *max_sectors)
597{
598 const sector_t this_sector = r1_bio->sector;
599 int sectors;
600 int best_good_sectors;
601 int best_disk, best_dist_disk, best_pending_disk;
602 int has_nonrot_disk;
603 int disk;
604 sector_t best_dist;
605 unsigned int min_pending;
606 struct md_rdev *rdev;
607 int choose_first;
608 int choose_next_idle;
609
610 rcu_read_lock();
611 /*
612 * Check if we can balance. We can balance on the whole
613 * device if no resync is going on, or below the resync window.
614 * We take the first readable disk when above the resync window.
615 */
616 retry:
617 sectors = r1_bio->sectors;
618 best_disk = -1;
619 best_dist_disk = -1;
620 best_dist = MaxSector;
621 best_pending_disk = -1;
622 min_pending = UINT_MAX;
623 best_good_sectors = 0;
624 has_nonrot_disk = 0;
625 choose_next_idle = 0;
626 clear_bit(R1BIO_FailFast, &r1_bio->state);
627
628 if ((conf->mddev->recovery_cp < this_sector + sectors) ||
629 (mddev_is_clustered(conf->mddev) &&
630 md_cluster_ops->area_resyncing(conf->mddev, READ, this_sector,
631 this_sector + sectors)))
632 choose_first = 1;
633 else
634 choose_first = 0;
635
636 for (disk = 0 ; disk < conf->raid_disks * 2 ; disk++) {
637 sector_t dist;
638 sector_t first_bad;
639 int bad_sectors;
640 unsigned int pending;
641 bool nonrot;
642
643 rdev = rcu_dereference(conf->mirrors[disk].rdev);
644 if (r1_bio->bios[disk] == IO_BLOCKED
645 || rdev == NULL
646 || test_bit(Faulty, &rdev->flags))
647 continue;
648 if (!test_bit(In_sync, &rdev->flags) &&
649 rdev->recovery_offset < this_sector + sectors)
650 continue;
651 if (test_bit(WriteMostly, &rdev->flags)) {
652 /* Don't balance among write-mostly, just
653 * use the first as a last resort */
654 if (best_dist_disk < 0) {
655 if (is_badblock(rdev, this_sector, sectors,
656 &first_bad, &bad_sectors)) {
657 if (first_bad <= this_sector)
658 /* Cannot use this */
659 continue;
660 best_good_sectors = first_bad - this_sector;
661 } else
662 best_good_sectors = sectors;
663 best_dist_disk = disk;
664 best_pending_disk = disk;
665 }
666 continue;
667 }
668 /* This is a reasonable device to use. It might
669 * even be best.
670 */
671 if (is_badblock(rdev, this_sector, sectors,
672 &first_bad, &bad_sectors)) {
673 if (best_dist < MaxSector)
674 /* already have a better device */
675 continue;
676 if (first_bad <= this_sector) {
677 /* cannot read here. If this is the 'primary'
678 * device, then we must not read beyond
679 * bad_sectors from another device..
680 */
681 bad_sectors -= (this_sector - first_bad);
682 if (choose_first && sectors > bad_sectors)
683 sectors = bad_sectors;
684 if (best_good_sectors > sectors)
685 best_good_sectors = sectors;
686
687 } else {
688 sector_t good_sectors = first_bad - this_sector;
689 if (good_sectors > best_good_sectors) {
690 best_good_sectors = good_sectors;
691 best_disk = disk;
692 }
693 if (choose_first)
694 break;
695 }
696 continue;
697 } else {
698 if ((sectors > best_good_sectors) && (best_disk >= 0))
699 best_disk = -1;
700 best_good_sectors = sectors;
701 }
702
703 if (best_disk >= 0)
704 /* At least two disks to choose from so failfast is OK */
705 set_bit(R1BIO_FailFast, &r1_bio->state);
706
707 nonrot = blk_queue_nonrot(bdev_get_queue(rdev->bdev));
708 has_nonrot_disk |= nonrot;
709 pending = atomic_read(&rdev->nr_pending);
710 dist = abs(this_sector - conf->mirrors[disk].head_position);
711 if (choose_first) {
712 best_disk = disk;
713 break;
714 }
715 /* Don't change to another disk for sequential reads */
716 if (conf->mirrors[disk].next_seq_sect == this_sector
717 || dist == 0) {
718 int opt_iosize = bdev_io_opt(rdev->bdev) >> 9;
719 struct raid1_info *mirror = &conf->mirrors[disk];
720
721 best_disk = disk;
722 /*
723 * If buffered sequential IO size exceeds optimal
724 * iosize, check if there is idle disk. If yes, choose
725 * the idle disk. read_balance could already choose an
726 * idle disk before noticing it's a sequential IO in
727 * this disk. This doesn't matter because this disk
728 * will idle, next time it will be utilized after the
729 * first disk has IO size exceeds optimal iosize. In
730 * this way, iosize of the first disk will be optimal
731 * iosize at least. iosize of the second disk might be
732 * small, but not a big deal since when the second disk
733 * starts IO, the first disk is likely still busy.
734 */
735 if (nonrot && opt_iosize > 0 &&
736 mirror->seq_start != MaxSector &&
737 mirror->next_seq_sect > opt_iosize &&
738 mirror->next_seq_sect - opt_iosize >=
739 mirror->seq_start) {
740 choose_next_idle = 1;
741 continue;
742 }
743 break;
744 }
745
746 if (choose_next_idle)
747 continue;
748
749 if (min_pending > pending) {
750 min_pending = pending;
751 best_pending_disk = disk;
752 }
753
754 if (dist < best_dist) {
755 best_dist = dist;
756 best_dist_disk = disk;
757 }
758 }
759
760 /*
761 * If all disks are rotational, choose the closest disk. If any disk is
762 * non-rotational, choose the disk with less pending request even the
763 * disk is rotational, which might/might not be optimal for raids with
764 * mixed ratation/non-rotational disks depending on workload.
765 */
766 if (best_disk == -1) {
767 if (has_nonrot_disk || min_pending == 0)
768 best_disk = best_pending_disk;
769 else
770 best_disk = best_dist_disk;
771 }
772
773 if (best_disk >= 0) {
774 rdev = rcu_dereference(conf->mirrors[best_disk].rdev);
775 if (!rdev)
776 goto retry;
777 atomic_inc(&rdev->nr_pending);
778 sectors = best_good_sectors;
779
780 if (conf->mirrors[best_disk].next_seq_sect != this_sector)
781 conf->mirrors[best_disk].seq_start = this_sector;
782
783 conf->mirrors[best_disk].next_seq_sect = this_sector + sectors;
784 }
785 rcu_read_unlock();
786 *max_sectors = sectors;
787
788 return best_disk;
789}
790
791static void flush_bio_list(struct r1conf *conf, struct bio *bio)
792{
793 /* flush any pending bitmap writes to disk before proceeding w/ I/O */
794 md_bitmap_unplug(conf->mddev->bitmap);
795 wake_up(&conf->wait_barrier);
796
797 while (bio) { /* submit pending writes */
798 struct bio *next = bio->bi_next;
799 struct md_rdev *rdev = (void *)bio->bi_bdev;
800 bio->bi_next = NULL;
801 bio_set_dev(bio, rdev->bdev);
802 if (test_bit(Faulty, &rdev->flags)) {
803 bio_io_error(bio);
804 } else if (unlikely((bio_op(bio) == REQ_OP_DISCARD) &&
805 !blk_queue_discard(bio->bi_bdev->bd_disk->queue)))
806 /* Just ignore it */
807 bio_endio(bio);
808 else
809 submit_bio_noacct(bio);
810 bio = next;
811 cond_resched();
812 }
813}
814
815static void flush_pending_writes(struct r1conf *conf)
816{
817 /* Any writes that have been queued but are awaiting
818 * bitmap updates get flushed here.
819 */
820 spin_lock_irq(&conf->device_lock);
821
822 if (conf->pending_bio_list.head) {
823 struct blk_plug plug;
824 struct bio *bio;
825
826 bio = bio_list_get(&conf->pending_bio_list);
827 conf->pending_count = 0;
828 spin_unlock_irq(&conf->device_lock);
829
830 /*
831 * As this is called in a wait_event() loop (see freeze_array),
832 * current->state might be TASK_UNINTERRUPTIBLE which will
833 * cause a warning when we prepare to wait again. As it is
834 * rare that this path is taken, it is perfectly safe to force
835 * us to go around the wait_event() loop again, so the warning
836 * is a false-positive. Silence the warning by resetting
837 * thread state
838 */
839 __set_current_state(TASK_RUNNING);
840 blk_start_plug(&plug);
841 flush_bio_list(conf, bio);
842 blk_finish_plug(&plug);
843 } else
844 spin_unlock_irq(&conf->device_lock);
845}
846
847/* Barriers....
848 * Sometimes we need to suspend IO while we do something else,
849 * either some resync/recovery, or reconfigure the array.
850 * To do this we raise a 'barrier'.
851 * The 'barrier' is a counter that can be raised multiple times
852 * to count how many activities are happening which preclude
853 * normal IO.
854 * We can only raise the barrier if there is no pending IO.
855 * i.e. if nr_pending == 0.
856 * We choose only to raise the barrier if no-one is waiting for the
857 * barrier to go down. This means that as soon as an IO request
858 * is ready, no other operations which require a barrier will start
859 * until the IO request has had a chance.
860 *
861 * So: regular IO calls 'wait_barrier'. When that returns there
862 * is no backgroup IO happening, It must arrange to call
863 * allow_barrier when it has finished its IO.
864 * backgroup IO calls must call raise_barrier. Once that returns
865 * there is no normal IO happeing. It must arrange to call
866 * lower_barrier when the particular background IO completes.
867 *
868 * If resync/recovery is interrupted, returns -EINTR;
869 * Otherwise, returns 0.
870 */
871static int raise_barrier(struct r1conf *conf, sector_t sector_nr)
872{
873 int idx = sector_to_idx(sector_nr);
874
875 spin_lock_irq(&conf->resync_lock);
876
877 /* Wait until no block IO is waiting */
878 wait_event_lock_irq(conf->wait_barrier,
879 !atomic_read(&conf->nr_waiting[idx]),
880 conf->resync_lock);
881
882 /* block any new IO from starting */
883 atomic_inc(&conf->barrier[idx]);
884 /*
885 * In raise_barrier() we firstly increase conf->barrier[idx] then
886 * check conf->nr_pending[idx]. In _wait_barrier() we firstly
887 * increase conf->nr_pending[idx] then check conf->barrier[idx].
888 * A memory barrier here to make sure conf->nr_pending[idx] won't
889 * be fetched before conf->barrier[idx] is increased. Otherwise
890 * there will be a race between raise_barrier() and _wait_barrier().
891 */
892 smp_mb__after_atomic();
893
894 /* For these conditions we must wait:
895 * A: while the array is in frozen state
896 * B: while conf->nr_pending[idx] is not 0, meaning regular I/O
897 * existing in corresponding I/O barrier bucket.
898 * C: while conf->barrier[idx] >= RESYNC_DEPTH, meaning reaches
899 * max resync count which allowed on current I/O barrier bucket.
900 */
901 wait_event_lock_irq(conf->wait_barrier,
902 (!conf->array_frozen &&
903 !atomic_read(&conf->nr_pending[idx]) &&
904 atomic_read(&conf->barrier[idx]) < RESYNC_DEPTH) ||
905 test_bit(MD_RECOVERY_INTR, &conf->mddev->recovery),
906 conf->resync_lock);
907
908 if (test_bit(MD_RECOVERY_INTR, &conf->mddev->recovery)) {
909 atomic_dec(&conf->barrier[idx]);
910 spin_unlock_irq(&conf->resync_lock);
911 wake_up(&conf->wait_barrier);
912 return -EINTR;
913 }
914
915 atomic_inc(&conf->nr_sync_pending);
916 spin_unlock_irq(&conf->resync_lock);
917
918 return 0;
919}
920
921static void lower_barrier(struct r1conf *conf, sector_t sector_nr)
922{
923 int idx = sector_to_idx(sector_nr);
924
925 BUG_ON(atomic_read(&conf->barrier[idx]) <= 0);
926
927 atomic_dec(&conf->barrier[idx]);
928 atomic_dec(&conf->nr_sync_pending);
929 wake_up(&conf->wait_barrier);
930}
931
932static void _wait_barrier(struct r1conf *conf, int idx)
933{
934 /*
935 * We need to increase conf->nr_pending[idx] very early here,
936 * then raise_barrier() can be blocked when it waits for
937 * conf->nr_pending[idx] to be 0. Then we can avoid holding
938 * conf->resync_lock when there is no barrier raised in same
939 * barrier unit bucket. Also if the array is frozen, I/O
940 * should be blocked until array is unfrozen.
941 */
942 atomic_inc(&conf->nr_pending[idx]);
943 /*
944 * In _wait_barrier() we firstly increase conf->nr_pending[idx], then
945 * check conf->barrier[idx]. In raise_barrier() we firstly increase
946 * conf->barrier[idx], then check conf->nr_pending[idx]. A memory
947 * barrier is necessary here to make sure conf->barrier[idx] won't be
948 * fetched before conf->nr_pending[idx] is increased. Otherwise there
949 * will be a race between _wait_barrier() and raise_barrier().
950 */
951 smp_mb__after_atomic();
952
953 /*
954 * Don't worry about checking two atomic_t variables at same time
955 * here. If during we check conf->barrier[idx], the array is
956 * frozen (conf->array_frozen is 1), and chonf->barrier[idx] is
957 * 0, it is safe to return and make the I/O continue. Because the
958 * array is frozen, all I/O returned here will eventually complete
959 * or be queued, no race will happen. See code comment in
960 * frozen_array().
961 */
962 if (!READ_ONCE(conf->array_frozen) &&
963 !atomic_read(&conf->barrier[idx]))
964 return;
965
966 /*
967 * After holding conf->resync_lock, conf->nr_pending[idx]
968 * should be decreased before waiting for barrier to drop.
969 * Otherwise, we may encounter a race condition because
970 * raise_barrer() might be waiting for conf->nr_pending[idx]
971 * to be 0 at same time.
972 */
973 spin_lock_irq(&conf->resync_lock);
974 atomic_inc(&conf->nr_waiting[idx]);
975 atomic_dec(&conf->nr_pending[idx]);
976 /*
977 * In case freeze_array() is waiting for
978 * get_unqueued_pending() == extra
979 */
980 wake_up(&conf->wait_barrier);
981 /* Wait for the barrier in same barrier unit bucket to drop. */
982 wait_event_lock_irq(conf->wait_barrier,
983 !conf->array_frozen &&
984 !atomic_read(&conf->barrier[idx]),
985 conf->resync_lock);
986 atomic_inc(&conf->nr_pending[idx]);
987 atomic_dec(&conf->nr_waiting[idx]);
988 spin_unlock_irq(&conf->resync_lock);
989}
990
991static void wait_read_barrier(struct r1conf *conf, sector_t sector_nr)
992{
993 int idx = sector_to_idx(sector_nr);
994
995 /*
996 * Very similar to _wait_barrier(). The difference is, for read
997 * I/O we don't need wait for sync I/O, but if the whole array
998 * is frozen, the read I/O still has to wait until the array is
999 * unfrozen. Since there is no ordering requirement with
1000 * conf->barrier[idx] here, memory barrier is unnecessary as well.
1001 */
1002 atomic_inc(&conf->nr_pending[idx]);
1003
1004 if (!READ_ONCE(conf->array_frozen))
1005 return;
1006
1007 spin_lock_irq(&conf->resync_lock);
1008 atomic_inc(&conf->nr_waiting[idx]);
1009 atomic_dec(&conf->nr_pending[idx]);
1010 /*
1011 * In case freeze_array() is waiting for
1012 * get_unqueued_pending() == extra
1013 */
1014 wake_up(&conf->wait_barrier);
1015 /* Wait for array to be unfrozen */
1016 wait_event_lock_irq(conf->wait_barrier,
1017 !conf->array_frozen,
1018 conf->resync_lock);
1019 atomic_inc(&conf->nr_pending[idx]);
1020 atomic_dec(&conf->nr_waiting[idx]);
1021 spin_unlock_irq(&conf->resync_lock);
1022}
1023
1024static void wait_barrier(struct r1conf *conf, sector_t sector_nr)
1025{
1026 int idx = sector_to_idx(sector_nr);
1027
1028 _wait_barrier(conf, idx);
1029}
1030
1031static void _allow_barrier(struct r1conf *conf, int idx)
1032{
1033 atomic_dec(&conf->nr_pending[idx]);
1034 wake_up(&conf->wait_barrier);
1035}
1036
1037static void allow_barrier(struct r1conf *conf, sector_t sector_nr)
1038{
1039 int idx = sector_to_idx(sector_nr);
1040
1041 _allow_barrier(conf, idx);
1042}
1043
1044/* conf->resync_lock should be held */
1045static int get_unqueued_pending(struct r1conf *conf)
1046{
1047 int idx, ret;
1048
1049 ret = atomic_read(&conf->nr_sync_pending);
1050 for (idx = 0; idx < BARRIER_BUCKETS_NR; idx++)
1051 ret += atomic_read(&conf->nr_pending[idx]) -
1052 atomic_read(&conf->nr_queued[idx]);
1053
1054 return ret;
1055}
1056
1057static void freeze_array(struct r1conf *conf, int extra)
1058{
1059 /* Stop sync I/O and normal I/O and wait for everything to
1060 * go quiet.
1061 * This is called in two situations:
1062 * 1) management command handlers (reshape, remove disk, quiesce).
1063 * 2) one normal I/O request failed.
1064
1065 * After array_frozen is set to 1, new sync IO will be blocked at
1066 * raise_barrier(), and new normal I/O will blocked at _wait_barrier()
1067 * or wait_read_barrier(). The flying I/Os will either complete or be
1068 * queued. When everything goes quite, there are only queued I/Os left.
1069
1070 * Every flying I/O contributes to a conf->nr_pending[idx], idx is the
1071 * barrier bucket index which this I/O request hits. When all sync and
1072 * normal I/O are queued, sum of all conf->nr_pending[] will match sum
1073 * of all conf->nr_queued[]. But normal I/O failure is an exception,
1074 * in handle_read_error(), we may call freeze_array() before trying to
1075 * fix the read error. In this case, the error read I/O is not queued,
1076 * so get_unqueued_pending() == 1.
1077 *
1078 * Therefore before this function returns, we need to wait until
1079 * get_unqueued_pendings(conf) gets equal to extra. For
1080 * normal I/O context, extra is 1, in rested situations extra is 0.
1081 */
1082 spin_lock_irq(&conf->resync_lock);
1083 conf->array_frozen = 1;
1084 raid1_log(conf->mddev, "wait freeze");
1085 wait_event_lock_irq_cmd(
1086 conf->wait_barrier,
1087 get_unqueued_pending(conf) == extra,
1088 conf->resync_lock,
1089 flush_pending_writes(conf));
1090 spin_unlock_irq(&conf->resync_lock);
1091}
1092static void unfreeze_array(struct r1conf *conf)
1093{
1094 /* reverse the effect of the freeze */
1095 spin_lock_irq(&conf->resync_lock);
1096 conf->array_frozen = 0;
1097 spin_unlock_irq(&conf->resync_lock);
1098 wake_up(&conf->wait_barrier);
1099}
1100
1101static void alloc_behind_master_bio(struct r1bio *r1_bio,
1102 struct bio *bio)
1103{
1104 int size = bio->bi_iter.bi_size;
1105 unsigned vcnt = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
1106 int i = 0;
1107 struct bio *behind_bio = NULL;
1108
1109 behind_bio = bio_alloc_bioset(GFP_NOIO, vcnt, &r1_bio->mddev->bio_set);
1110 if (!behind_bio)
1111 return;
1112
1113 /* discard op, we don't support writezero/writesame yet */
1114 if (!bio_has_data(bio)) {
1115 behind_bio->bi_iter.bi_size = size;
1116 goto skip_copy;
1117 }
1118
1119 behind_bio->bi_write_hint = bio->bi_write_hint;
1120
1121 while (i < vcnt && size) {
1122 struct page *page;
1123 int len = min_t(int, PAGE_SIZE, size);
1124
1125 page = alloc_page(GFP_NOIO);
1126 if (unlikely(!page))
1127 goto free_pages;
1128
1129 bio_add_page(behind_bio, page, len, 0);
1130
1131 size -= len;
1132 i++;
1133 }
1134
1135 bio_copy_data(behind_bio, bio);
1136skip_copy:
1137 r1_bio->behind_master_bio = behind_bio;
1138 set_bit(R1BIO_BehindIO, &r1_bio->state);
1139
1140 return;
1141
1142free_pages:
1143 pr_debug("%dB behind alloc failed, doing sync I/O\n",
1144 bio->bi_iter.bi_size);
1145 bio_free_pages(behind_bio);
1146 bio_put(behind_bio);
1147}
1148
1149struct raid1_plug_cb {
1150 struct blk_plug_cb cb;
1151 struct bio_list pending;
1152 int pending_cnt;
1153};
1154
1155static void raid1_unplug(struct blk_plug_cb *cb, bool from_schedule)
1156{
1157 struct raid1_plug_cb *plug = container_of(cb, struct raid1_plug_cb,
1158 cb);
1159 struct mddev *mddev = plug->cb.data;
1160 struct r1conf *conf = mddev->private;
1161 struct bio *bio;
1162
1163 if (from_schedule || current->bio_list) {
1164 spin_lock_irq(&conf->device_lock);
1165 bio_list_merge(&conf->pending_bio_list, &plug->pending);
1166 conf->pending_count += plug->pending_cnt;
1167 spin_unlock_irq(&conf->device_lock);
1168 wake_up(&conf->wait_barrier);
1169 md_wakeup_thread(mddev->thread);
1170 kfree(plug);
1171 return;
1172 }
1173
1174 /* we aren't scheduling, so we can do the write-out directly. */
1175 bio = bio_list_get(&plug->pending);
1176 flush_bio_list(conf, bio);
1177 kfree(plug);
1178}
1179
1180static void init_r1bio(struct r1bio *r1_bio, struct mddev *mddev, struct bio *bio)
1181{
1182 r1_bio->master_bio = bio;
1183 r1_bio->sectors = bio_sectors(bio);
1184 r1_bio->state = 0;
1185 r1_bio->mddev = mddev;
1186 r1_bio->sector = bio->bi_iter.bi_sector;
1187}
1188
1189static inline struct r1bio *
1190alloc_r1bio(struct mddev *mddev, struct bio *bio)
1191{
1192 struct r1conf *conf = mddev->private;
1193 struct r1bio *r1_bio;
1194
1195 r1_bio = mempool_alloc(&conf->r1bio_pool, GFP_NOIO);
1196 /* Ensure no bio records IO_BLOCKED */
1197 memset(r1_bio->bios, 0, conf->raid_disks * sizeof(r1_bio->bios[0]));
1198 init_r1bio(r1_bio, mddev, bio);
1199 return r1_bio;
1200}
1201
1202static void raid1_read_request(struct mddev *mddev, struct bio *bio,
1203 int max_read_sectors, struct r1bio *r1_bio)
1204{
1205 struct r1conf *conf = mddev->private;
1206 struct raid1_info *mirror;
1207 struct bio *read_bio;
1208 struct bitmap *bitmap = mddev->bitmap;
1209 const int op = bio_op(bio);
1210 const unsigned long do_sync = (bio->bi_opf & REQ_SYNC);
1211 int max_sectors;
1212 int rdisk;
1213 bool r1bio_existed = !!r1_bio;
1214 char b[BDEVNAME_SIZE];
1215
1216 /*
1217 * If r1_bio is set, we are blocking the raid1d thread
1218 * so there is a tiny risk of deadlock. So ask for
1219 * emergency memory if needed.
1220 */
1221 gfp_t gfp = r1_bio ? (GFP_NOIO | __GFP_HIGH) : GFP_NOIO;
1222
1223 if (r1bio_existed) {
1224 /* Need to get the block device name carefully */
1225 struct md_rdev *rdev;
1226 rcu_read_lock();
1227 rdev = rcu_dereference(conf->mirrors[r1_bio->read_disk].rdev);
1228 if (rdev)
1229 bdevname(rdev->bdev, b);
1230 else
1231 strcpy(b, "???");
1232 rcu_read_unlock();
1233 }
1234
1235 /*
1236 * Still need barrier for READ in case that whole
1237 * array is frozen.
1238 */
1239 wait_read_barrier(conf, bio->bi_iter.bi_sector);
1240
1241 if (!r1_bio)
1242 r1_bio = alloc_r1bio(mddev, bio);
1243 else
1244 init_r1bio(r1_bio, mddev, bio);
1245 r1_bio->sectors = max_read_sectors;
1246
1247 /*
1248 * make_request() can abort the operation when read-ahead is being
1249 * used and no empty request is available.
1250 */
1251 rdisk = read_balance(conf, r1_bio, &max_sectors);
1252
1253 if (rdisk < 0) {
1254 /* couldn't find anywhere to read from */
1255 if (r1bio_existed) {
1256 pr_crit_ratelimited("md/raid1:%s: %s: unrecoverable I/O read error for block %llu\n",
1257 mdname(mddev),
1258 b,
1259 (unsigned long long)r1_bio->sector);
1260 }
1261 raid_end_bio_io(r1_bio);
1262 return;
1263 }
1264 mirror = conf->mirrors + rdisk;
1265
1266 if (r1bio_existed)
1267 pr_info_ratelimited("md/raid1:%s: redirecting sector %llu to other mirror: %s\n",
1268 mdname(mddev),
1269 (unsigned long long)r1_bio->sector,
1270 bdevname(mirror->rdev->bdev, b));
1271
1272 if (test_bit(WriteMostly, &mirror->rdev->flags) &&
1273 bitmap) {
1274 /*
1275 * Reading from a write-mostly device must take care not to
1276 * over-take any writes that are 'behind'
1277 */
1278 raid1_log(mddev, "wait behind writes");
1279 wait_event(bitmap->behind_wait,
1280 atomic_read(&bitmap->behind_writes) == 0);
1281 }
1282
1283 if (max_sectors < bio_sectors(bio)) {
1284 struct bio *split = bio_split(bio, max_sectors,
1285 gfp, &conf->bio_split);
1286 bio_chain(split, bio);
1287 submit_bio_noacct(bio);
1288 bio = split;
1289 r1_bio->master_bio = bio;
1290 r1_bio->sectors = max_sectors;
1291 }
1292
1293 r1_bio->read_disk = rdisk;
1294
1295 if (!r1bio_existed && blk_queue_io_stat(bio->bi_bdev->bd_disk->queue))
1296 r1_bio->start_time = bio_start_io_acct(bio);
1297
1298 read_bio = bio_clone_fast(bio, gfp, &mddev->bio_set);
1299
1300 r1_bio->bios[rdisk] = read_bio;
1301
1302 read_bio->bi_iter.bi_sector = r1_bio->sector +
1303 mirror->rdev->data_offset;
1304 bio_set_dev(read_bio, mirror->rdev->bdev);
1305 read_bio->bi_end_io = raid1_end_read_request;
1306 bio_set_op_attrs(read_bio, op, do_sync);
1307 if (test_bit(FailFast, &mirror->rdev->flags) &&
1308 test_bit(R1BIO_FailFast, &r1_bio->state))
1309 read_bio->bi_opf |= MD_FAILFAST;
1310 read_bio->bi_private = r1_bio;
1311
1312 if (mddev->gendisk)
1313 trace_block_bio_remap(read_bio, disk_devt(mddev->gendisk),
1314 r1_bio->sector);
1315
1316 submit_bio_noacct(read_bio);
1317}
1318
1319static void raid1_write_request(struct mddev *mddev, struct bio *bio,
1320 int max_write_sectors)
1321{
1322 struct r1conf *conf = mddev->private;
1323 struct r1bio *r1_bio;
1324 int i, disks;
1325 struct bitmap *bitmap = mddev->bitmap;
1326 unsigned long flags;
1327 struct md_rdev *blocked_rdev;
1328 struct blk_plug_cb *cb;
1329 struct raid1_plug_cb *plug = NULL;
1330 int first_clone;
1331 int max_sectors;
1332 bool write_behind = false;
1333
1334 if (mddev_is_clustered(mddev) &&
1335 md_cluster_ops->area_resyncing(mddev, WRITE,
1336 bio->bi_iter.bi_sector, bio_end_sector(bio))) {
1337
1338 DEFINE_WAIT(w);
1339 for (;;) {
1340 prepare_to_wait(&conf->wait_barrier,
1341 &w, TASK_IDLE);
1342 if (!md_cluster_ops->area_resyncing(mddev, WRITE,
1343 bio->bi_iter.bi_sector,
1344 bio_end_sector(bio)))
1345 break;
1346 schedule();
1347 }
1348 finish_wait(&conf->wait_barrier, &w);
1349 }
1350
1351 /*
1352 * Register the new request and wait if the reconstruction
1353 * thread has put up a bar for new requests.
1354 * Continue immediately if no resync is active currently.
1355 */
1356 wait_barrier(conf, bio->bi_iter.bi_sector);
1357
1358 r1_bio = alloc_r1bio(mddev, bio);
1359 r1_bio->sectors = max_write_sectors;
1360
1361 if (conf->pending_count >= max_queued_requests) {
1362 md_wakeup_thread(mddev->thread);
1363 raid1_log(mddev, "wait queued");
1364 wait_event(conf->wait_barrier,
1365 conf->pending_count < max_queued_requests);
1366 }
1367 /* first select target devices under rcu_lock and
1368 * inc refcount on their rdev. Record them by setting
1369 * bios[x] to bio
1370 * If there are known/acknowledged bad blocks on any device on
1371 * which we have seen a write error, we want to avoid writing those
1372 * blocks.
1373 * This potentially requires several writes to write around
1374 * the bad blocks. Each set of writes gets it's own r1bio
1375 * with a set of bios attached.
1376 */
1377
1378 disks = conf->raid_disks * 2;
1379 retry_write:
1380 blocked_rdev = NULL;
1381 rcu_read_lock();
1382 max_sectors = r1_bio->sectors;
1383 for (i = 0; i < disks; i++) {
1384 struct md_rdev *rdev = rcu_dereference(conf->mirrors[i].rdev);
1385
1386 /*
1387 * The write-behind io is only attempted on drives marked as
1388 * write-mostly, which means we could allocate write behind
1389 * bio later.
1390 */
1391 if (rdev && test_bit(WriteMostly, &rdev->flags))
1392 write_behind = true;
1393
1394 if (rdev && unlikely(test_bit(Blocked, &rdev->flags))) {
1395 atomic_inc(&rdev->nr_pending);
1396 blocked_rdev = rdev;
1397 break;
1398 }
1399 r1_bio->bios[i] = NULL;
1400 if (!rdev || test_bit(Faulty, &rdev->flags)) {
1401 if (i < conf->raid_disks)
1402 set_bit(R1BIO_Degraded, &r1_bio->state);
1403 continue;
1404 }
1405
1406 atomic_inc(&rdev->nr_pending);
1407 if (test_bit(WriteErrorSeen, &rdev->flags)) {
1408 sector_t first_bad;
1409 int bad_sectors;
1410 int is_bad;
1411
1412 is_bad = is_badblock(rdev, r1_bio->sector, max_sectors,
1413 &first_bad, &bad_sectors);
1414 if (is_bad < 0) {
1415 /* mustn't write here until the bad block is
1416 * acknowledged*/
1417 set_bit(BlockedBadBlocks, &rdev->flags);
1418 blocked_rdev = rdev;
1419 break;
1420 }
1421 if (is_bad && first_bad <= r1_bio->sector) {
1422 /* Cannot write here at all */
1423 bad_sectors -= (r1_bio->sector - first_bad);
1424 if (bad_sectors < max_sectors)
1425 /* mustn't write more than bad_sectors
1426 * to other devices yet
1427 */
1428 max_sectors = bad_sectors;
1429 rdev_dec_pending(rdev, mddev);
1430 /* We don't set R1BIO_Degraded as that
1431 * only applies if the disk is
1432 * missing, so it might be re-added,
1433 * and we want to know to recover this
1434 * chunk.
1435 * In this case the device is here,
1436 * and the fact that this chunk is not
1437 * in-sync is recorded in the bad
1438 * block log
1439 */
1440 continue;
1441 }
1442 if (is_bad) {
1443 int good_sectors = first_bad - r1_bio->sector;
1444 if (good_sectors < max_sectors)
1445 max_sectors = good_sectors;
1446 }
1447 }
1448 r1_bio->bios[i] = bio;
1449 }
1450 rcu_read_unlock();
1451
1452 if (unlikely(blocked_rdev)) {
1453 /* Wait for this device to become unblocked */
1454 int j;
1455
1456 for (j = 0; j < i; j++)
1457 if (r1_bio->bios[j])
1458 rdev_dec_pending(conf->mirrors[j].rdev, mddev);
1459 r1_bio->state = 0;
1460 allow_barrier(conf, bio->bi_iter.bi_sector);
1461 raid1_log(mddev, "wait rdev %d blocked", blocked_rdev->raid_disk);
1462 md_wait_for_blocked_rdev(blocked_rdev, mddev);
1463 wait_barrier(conf, bio->bi_iter.bi_sector);
1464 goto retry_write;
1465 }
1466
1467 /*
1468 * When using a bitmap, we may call alloc_behind_master_bio below.
1469 * alloc_behind_master_bio allocates a copy of the data payload a page
1470 * at a time and thus needs a new bio that can fit the whole payload
1471 * this bio in page sized chunks.
1472 */
1473 if (write_behind && bitmap)
1474 max_sectors = min_t(int, max_sectors,
1475 BIO_MAX_VECS * (PAGE_SIZE >> 9));
1476 if (max_sectors < bio_sectors(bio)) {
1477 struct bio *split = bio_split(bio, max_sectors,
1478 GFP_NOIO, &conf->bio_split);
1479 bio_chain(split, bio);
1480 submit_bio_noacct(bio);
1481 bio = split;
1482 r1_bio->master_bio = bio;
1483 r1_bio->sectors = max_sectors;
1484 }
1485
1486 if (blk_queue_io_stat(bio->bi_bdev->bd_disk->queue))
1487 r1_bio->start_time = bio_start_io_acct(bio);
1488 atomic_set(&r1_bio->remaining, 1);
1489 atomic_set(&r1_bio->behind_remaining, 0);
1490
1491 first_clone = 1;
1492
1493 for (i = 0; i < disks; i++) {
1494 struct bio *mbio = NULL;
1495 struct md_rdev *rdev = conf->mirrors[i].rdev;
1496 if (!r1_bio->bios[i])
1497 continue;
1498
1499 if (first_clone) {
1500 /* do behind I/O ?
1501 * Not if there are too many, or cannot
1502 * allocate memory, or a reader on WriteMostly
1503 * is waiting for behind writes to flush */
1504 if (bitmap &&
1505 (atomic_read(&bitmap->behind_writes)
1506 < mddev->bitmap_info.max_write_behind) &&
1507 !waitqueue_active(&bitmap->behind_wait)) {
1508 alloc_behind_master_bio(r1_bio, bio);
1509 }
1510
1511 md_bitmap_startwrite(bitmap, r1_bio->sector, r1_bio->sectors,
1512 test_bit(R1BIO_BehindIO, &r1_bio->state));
1513 first_clone = 0;
1514 }
1515
1516 if (r1_bio->behind_master_bio)
1517 mbio = bio_clone_fast(r1_bio->behind_master_bio,
1518 GFP_NOIO, &mddev->bio_set);
1519 else
1520 mbio = bio_clone_fast(bio, GFP_NOIO, &mddev->bio_set);
1521
1522 if (r1_bio->behind_master_bio) {
1523 if (test_bit(CollisionCheck, &rdev->flags))
1524 wait_for_serialization(rdev, r1_bio);
1525 if (test_bit(WriteMostly, &rdev->flags))
1526 atomic_inc(&r1_bio->behind_remaining);
1527 } else if (mddev->serialize_policy)
1528 wait_for_serialization(rdev, r1_bio);
1529
1530 r1_bio->bios[i] = mbio;
1531
1532 mbio->bi_iter.bi_sector = (r1_bio->sector +
1533 conf->mirrors[i].rdev->data_offset);
1534 bio_set_dev(mbio, conf->mirrors[i].rdev->bdev);
1535 mbio->bi_end_io = raid1_end_write_request;
1536 mbio->bi_opf = bio_op(bio) | (bio->bi_opf & (REQ_SYNC | REQ_FUA));
1537 if (test_bit(FailFast, &conf->mirrors[i].rdev->flags) &&
1538 !test_bit(WriteMostly, &conf->mirrors[i].rdev->flags) &&
1539 conf->raid_disks - mddev->degraded > 1)
1540 mbio->bi_opf |= MD_FAILFAST;
1541 mbio->bi_private = r1_bio;
1542
1543 atomic_inc(&r1_bio->remaining);
1544
1545 if (mddev->gendisk)
1546 trace_block_bio_remap(mbio, disk_devt(mddev->gendisk),
1547 r1_bio->sector);
1548 /* flush_pending_writes() needs access to the rdev so...*/
1549 mbio->bi_bdev = (void *)conf->mirrors[i].rdev;
1550
1551 cb = blk_check_plugged(raid1_unplug, mddev, sizeof(*plug));
1552 if (cb)
1553 plug = container_of(cb, struct raid1_plug_cb, cb);
1554 else
1555 plug = NULL;
1556 if (plug) {
1557 bio_list_add(&plug->pending, mbio);
1558 plug->pending_cnt++;
1559 } else {
1560 spin_lock_irqsave(&conf->device_lock, flags);
1561 bio_list_add(&conf->pending_bio_list, mbio);
1562 conf->pending_count++;
1563 spin_unlock_irqrestore(&conf->device_lock, flags);
1564 md_wakeup_thread(mddev->thread);
1565 }
1566 }
1567
1568 r1_bio_write_done(r1_bio);
1569
1570 /* In case raid1d snuck in to freeze_array */
1571 wake_up(&conf->wait_barrier);
1572}
1573
1574static bool raid1_make_request(struct mddev *mddev, struct bio *bio)
1575{
1576 sector_t sectors;
1577
1578 if (unlikely(bio->bi_opf & REQ_PREFLUSH)
1579 && md_flush_request(mddev, bio))
1580 return true;
1581
1582 /*
1583 * There is a limit to the maximum size, but
1584 * the read/write handler might find a lower limit
1585 * due to bad blocks. To avoid multiple splits,
1586 * we pass the maximum number of sectors down
1587 * and let the lower level perform the split.
1588 */
1589 sectors = align_to_barrier_unit_end(
1590 bio->bi_iter.bi_sector, bio_sectors(bio));
1591
1592 if (bio_data_dir(bio) == READ)
1593 raid1_read_request(mddev, bio, sectors, NULL);
1594 else {
1595 if (!md_write_start(mddev,bio))
1596 return false;
1597 raid1_write_request(mddev, bio, sectors);
1598 }
1599 return true;
1600}
1601
1602static void raid1_status(struct seq_file *seq, struct mddev *mddev)
1603{
1604 struct r1conf *conf = mddev->private;
1605 int i;
1606
1607 seq_printf(seq, " [%d/%d] [", conf->raid_disks,
1608 conf->raid_disks - mddev->degraded);
1609 rcu_read_lock();
1610 for (i = 0; i < conf->raid_disks; i++) {
1611 struct md_rdev *rdev = rcu_dereference(conf->mirrors[i].rdev);
1612 seq_printf(seq, "%s",
1613 rdev && test_bit(In_sync, &rdev->flags) ? "U" : "_");
1614 }
1615 rcu_read_unlock();
1616 seq_printf(seq, "]");
1617}
1618
1619static void raid1_error(struct mddev *mddev, struct md_rdev *rdev)
1620{
1621 char b[BDEVNAME_SIZE];
1622 struct r1conf *conf = mddev->private;
1623 unsigned long flags;
1624
1625 /*
1626 * If it is not operational, then we have already marked it as dead
1627 * else if it is the last working disks with "fail_last_dev == false",
1628 * ignore the error, let the next level up know.
1629 * else mark the drive as failed
1630 */
1631 spin_lock_irqsave(&conf->device_lock, flags);
1632 if (test_bit(In_sync, &rdev->flags) && !mddev->fail_last_dev
1633 && (conf->raid_disks - mddev->degraded) == 1) {
1634 /*
1635 * Don't fail the drive, act as though we were just a
1636 * normal single drive.
1637 * However don't try a recovery from this drive as
1638 * it is very likely to fail.
1639 */
1640 conf->recovery_disabled = mddev->recovery_disabled;
1641 spin_unlock_irqrestore(&conf->device_lock, flags);
1642 return;
1643 }
1644 set_bit(Blocked, &rdev->flags);
1645 if (test_and_clear_bit(In_sync, &rdev->flags))
1646 mddev->degraded++;
1647 set_bit(Faulty, &rdev->flags);
1648 spin_unlock_irqrestore(&conf->device_lock, flags);
1649 /*
1650 * if recovery is running, make sure it aborts.
1651 */
1652 set_bit(MD_RECOVERY_INTR, &mddev->recovery);
1653 set_mask_bits(&mddev->sb_flags, 0,
1654 BIT(MD_SB_CHANGE_DEVS) | BIT(MD_SB_CHANGE_PENDING));
1655 pr_crit("md/raid1:%s: Disk failure on %s, disabling device.\n"
1656 "md/raid1:%s: Operation continuing on %d devices.\n",
1657 mdname(mddev), bdevname(rdev->bdev, b),
1658 mdname(mddev), conf->raid_disks - mddev->degraded);
1659}
1660
1661static void print_conf(struct r1conf *conf)
1662{
1663 int i;
1664
1665 pr_debug("RAID1 conf printout:\n");
1666 if (!conf) {
1667 pr_debug("(!conf)\n");
1668 return;
1669 }
1670 pr_debug(" --- wd:%d rd:%d\n", conf->raid_disks - conf->mddev->degraded,
1671 conf->raid_disks);
1672
1673 rcu_read_lock();
1674 for (i = 0; i < conf->raid_disks; i++) {
1675 char b[BDEVNAME_SIZE];
1676 struct md_rdev *rdev = rcu_dereference(conf->mirrors[i].rdev);
1677 if (rdev)
1678 pr_debug(" disk %d, wo:%d, o:%d, dev:%s\n",
1679 i, !test_bit(In_sync, &rdev->flags),
1680 !test_bit(Faulty, &rdev->flags),
1681 bdevname(rdev->bdev,b));
1682 }
1683 rcu_read_unlock();
1684}
1685
1686static void close_sync(struct r1conf *conf)
1687{
1688 int idx;
1689
1690 for (idx = 0; idx < BARRIER_BUCKETS_NR; idx++) {
1691 _wait_barrier(conf, idx);
1692 _allow_barrier(conf, idx);
1693 }
1694
1695 mempool_exit(&conf->r1buf_pool);
1696}
1697
1698static int raid1_spare_active(struct mddev *mddev)
1699{
1700 int i;
1701 struct r1conf *conf = mddev->private;
1702 int count = 0;
1703 unsigned long flags;
1704
1705 /*
1706 * Find all failed disks within the RAID1 configuration
1707 * and mark them readable.
1708 * Called under mddev lock, so rcu protection not needed.
1709 * device_lock used to avoid races with raid1_end_read_request
1710 * which expects 'In_sync' flags and ->degraded to be consistent.
1711 */
1712 spin_lock_irqsave(&conf->device_lock, flags);
1713 for (i = 0; i < conf->raid_disks; i++) {
1714 struct md_rdev *rdev = conf->mirrors[i].rdev;
1715 struct md_rdev *repl = conf->mirrors[conf->raid_disks + i].rdev;
1716 if (repl
1717 && !test_bit(Candidate, &repl->flags)
1718 && repl->recovery_offset == MaxSector
1719 && !test_bit(Faulty, &repl->flags)
1720 && !test_and_set_bit(In_sync, &repl->flags)) {
1721 /* replacement has just become active */
1722 if (!rdev ||
1723 !test_and_clear_bit(In_sync, &rdev->flags))
1724 count++;
1725 if (rdev) {
1726 /* Replaced device not technically
1727 * faulty, but we need to be sure
1728 * it gets removed and never re-added
1729 */
1730 set_bit(Faulty, &rdev->flags);
1731 sysfs_notify_dirent_safe(
1732 rdev->sysfs_state);
1733 }
1734 }
1735 if (rdev
1736 && rdev->recovery_offset == MaxSector
1737 && !test_bit(Faulty, &rdev->flags)
1738 && !test_and_set_bit(In_sync, &rdev->flags)) {
1739 count++;
1740 sysfs_notify_dirent_safe(rdev->sysfs_state);
1741 }
1742 }
1743 mddev->degraded -= count;
1744 spin_unlock_irqrestore(&conf->device_lock, flags);
1745
1746 print_conf(conf);
1747 return count;
1748}
1749
1750static int raid1_add_disk(struct mddev *mddev, struct md_rdev *rdev)
1751{
1752 struct r1conf *conf = mddev->private;
1753 int err = -EEXIST;
1754 int mirror = 0;
1755 struct raid1_info *p;
1756 int first = 0;
1757 int last = conf->raid_disks - 1;
1758
1759 if (mddev->recovery_disabled == conf->recovery_disabled)
1760 return -EBUSY;
1761
1762 if (md_integrity_add_rdev(rdev, mddev))
1763 return -ENXIO;
1764
1765 if (rdev->raid_disk >= 0)
1766 first = last = rdev->raid_disk;
1767
1768 /*
1769 * find the disk ... but prefer rdev->saved_raid_disk
1770 * if possible.
1771 */
1772 if (rdev->saved_raid_disk >= 0 &&
1773 rdev->saved_raid_disk >= first &&
1774 rdev->saved_raid_disk < conf->raid_disks &&
1775 conf->mirrors[rdev->saved_raid_disk].rdev == NULL)
1776 first = last = rdev->saved_raid_disk;
1777
1778 for (mirror = first; mirror <= last; mirror++) {
1779 p = conf->mirrors + mirror;
1780 if (!p->rdev) {
1781 if (mddev->gendisk)
1782 disk_stack_limits(mddev->gendisk, rdev->bdev,
1783 rdev->data_offset << 9);
1784
1785 p->head_position = 0;
1786 rdev->raid_disk = mirror;
1787 err = 0;
1788 /* As all devices are equivalent, we don't need a full recovery
1789 * if this was recently any drive of the array
1790 */
1791 if (rdev->saved_raid_disk < 0)
1792 conf->fullsync = 1;
1793 rcu_assign_pointer(p->rdev, rdev);
1794 break;
1795 }
1796 if (test_bit(WantReplacement, &p->rdev->flags) &&
1797 p[conf->raid_disks].rdev == NULL) {
1798 /* Add this device as a replacement */
1799 clear_bit(In_sync, &rdev->flags);
1800 set_bit(Replacement, &rdev->flags);
1801 rdev->raid_disk = mirror;
1802 err = 0;
1803 conf->fullsync = 1;
1804 rcu_assign_pointer(p[conf->raid_disks].rdev, rdev);
1805 break;
1806 }
1807 }
1808 if (mddev->queue && blk_queue_discard(bdev_get_queue(rdev->bdev)))
1809 blk_queue_flag_set(QUEUE_FLAG_DISCARD, mddev->queue);
1810 print_conf(conf);
1811 return err;
1812}
1813
1814static int raid1_remove_disk(struct mddev *mddev, struct md_rdev *rdev)
1815{
1816 struct r1conf *conf = mddev->private;
1817 int err = 0;
1818 int number = rdev->raid_disk;
1819 struct raid1_info *p = conf->mirrors + number;
1820
1821 if (rdev != p->rdev)
1822 p = conf->mirrors + conf->raid_disks + number;
1823
1824 print_conf(conf);
1825 if (rdev == p->rdev) {
1826 if (test_bit(In_sync, &rdev->flags) ||
1827 atomic_read(&rdev->nr_pending)) {
1828 err = -EBUSY;
1829 goto abort;
1830 }
1831 /* Only remove non-faulty devices if recovery
1832 * is not possible.
1833 */
1834 if (!test_bit(Faulty, &rdev->flags) &&
1835 mddev->recovery_disabled != conf->recovery_disabled &&
1836 mddev->degraded < conf->raid_disks) {
1837 err = -EBUSY;
1838 goto abort;
1839 }
1840 p->rdev = NULL;
1841 if (!test_bit(RemoveSynchronized, &rdev->flags)) {
1842 synchronize_rcu();
1843 if (atomic_read(&rdev->nr_pending)) {
1844 /* lost the race, try later */
1845 err = -EBUSY;
1846 p->rdev = rdev;
1847 goto abort;
1848 }
1849 }
1850 if (conf->mirrors[conf->raid_disks + number].rdev) {
1851 /* We just removed a device that is being replaced.
1852 * Move down the replacement. We drain all IO before
1853 * doing this to avoid confusion.
1854 */
1855 struct md_rdev *repl =
1856 conf->mirrors[conf->raid_disks + number].rdev;
1857 freeze_array(conf, 0);
1858 if (atomic_read(&repl->nr_pending)) {
1859 /* It means that some queued IO of retry_list
1860 * hold repl. Thus, we cannot set replacement
1861 * as NULL, avoiding rdev NULL pointer
1862 * dereference in sync_request_write and
1863 * handle_write_finished.
1864 */
1865 err = -EBUSY;
1866 unfreeze_array(conf);
1867 goto abort;
1868 }
1869 clear_bit(Replacement, &repl->flags);
1870 p->rdev = repl;
1871 conf->mirrors[conf->raid_disks + number].rdev = NULL;
1872 unfreeze_array(conf);
1873 }
1874
1875 clear_bit(WantReplacement, &rdev->flags);
1876 err = md_integrity_register(mddev);
1877 }
1878abort:
1879
1880 print_conf(conf);
1881 return err;
1882}
1883
1884static void end_sync_read(struct bio *bio)
1885{
1886 struct r1bio *r1_bio = get_resync_r1bio(bio);
1887
1888 update_head_pos(r1_bio->read_disk, r1_bio);
1889
1890 /*
1891 * we have read a block, now it needs to be re-written,
1892 * or re-read if the read failed.
1893 * We don't do much here, just schedule handling by raid1d
1894 */
1895 if (!bio->bi_status)
1896 set_bit(R1BIO_Uptodate, &r1_bio->state);
1897
1898 if (atomic_dec_and_test(&r1_bio->remaining))
1899 reschedule_retry(r1_bio);
1900}
1901
1902static void abort_sync_write(struct mddev *mddev, struct r1bio *r1_bio)
1903{
1904 sector_t sync_blocks = 0;
1905 sector_t s = r1_bio->sector;
1906 long sectors_to_go = r1_bio->sectors;
1907
1908 /* make sure these bits don't get cleared. */
1909 do {
1910 md_bitmap_end_sync(mddev->bitmap, s, &sync_blocks, 1);
1911 s += sync_blocks;
1912 sectors_to_go -= sync_blocks;
1913 } while (sectors_to_go > 0);
1914}
1915
1916static void put_sync_write_buf(struct r1bio *r1_bio, int uptodate)
1917{
1918 if (atomic_dec_and_test(&r1_bio->remaining)) {
1919 struct mddev *mddev = r1_bio->mddev;
1920 int s = r1_bio->sectors;
1921
1922 if (test_bit(R1BIO_MadeGood, &r1_bio->state) ||
1923 test_bit(R1BIO_WriteError, &r1_bio->state))
1924 reschedule_retry(r1_bio);
1925 else {
1926 put_buf(r1_bio);
1927 md_done_sync(mddev, s, uptodate);
1928 }
1929 }
1930}
1931
1932static void end_sync_write(struct bio *bio)
1933{
1934 int uptodate = !bio->bi_status;
1935 struct r1bio *r1_bio = get_resync_r1bio(bio);
1936 struct mddev *mddev = r1_bio->mddev;
1937 struct r1conf *conf = mddev->private;
1938 sector_t first_bad;
1939 int bad_sectors;
1940 struct md_rdev *rdev = conf->mirrors[find_bio_disk(r1_bio, bio)].rdev;
1941
1942 if (!uptodate) {
1943 abort_sync_write(mddev, r1_bio);
1944 set_bit(WriteErrorSeen, &rdev->flags);
1945 if (!test_and_set_bit(WantReplacement, &rdev->flags))
1946 set_bit(MD_RECOVERY_NEEDED, &
1947 mddev->recovery);
1948 set_bit(R1BIO_WriteError, &r1_bio->state);
1949 } else if (is_badblock(rdev, r1_bio->sector, r1_bio->sectors,
1950 &first_bad, &bad_sectors) &&
1951 !is_badblock(conf->mirrors[r1_bio->read_disk].rdev,
1952 r1_bio->sector,
1953 r1_bio->sectors,
1954 &first_bad, &bad_sectors)
1955 )
1956 set_bit(R1BIO_MadeGood, &r1_bio->state);
1957
1958 put_sync_write_buf(r1_bio, uptodate);
1959}
1960
1961static int r1_sync_page_io(struct md_rdev *rdev, sector_t sector,
1962 int sectors, struct page *page, int rw)
1963{
1964 if (sync_page_io(rdev, sector, sectors << 9, page, rw, 0, false))
1965 /* success */
1966 return 1;
1967 if (rw == WRITE) {
1968 set_bit(WriteErrorSeen, &rdev->flags);
1969 if (!test_and_set_bit(WantReplacement,
1970 &rdev->flags))
1971 set_bit(MD_RECOVERY_NEEDED, &
1972 rdev->mddev->recovery);
1973 }
1974 /* need to record an error - either for the block or the device */
1975 if (!rdev_set_badblocks(rdev, sector, sectors, 0))
1976 md_error(rdev->mddev, rdev);
1977 return 0;
1978}
1979
1980static int fix_sync_read_error(struct r1bio *r1_bio)
1981{
1982 /* Try some synchronous reads of other devices to get
1983 * good data, much like with normal read errors. Only
1984 * read into the pages we already have so we don't
1985 * need to re-issue the read request.
1986 * We don't need to freeze the array, because being in an
1987 * active sync request, there is no normal IO, and
1988 * no overlapping syncs.
1989 * We don't need to check is_badblock() again as we
1990 * made sure that anything with a bad block in range
1991 * will have bi_end_io clear.
1992 */
1993 struct mddev *mddev = r1_bio->mddev;
1994 struct r1conf *conf = mddev->private;
1995 struct bio *bio = r1_bio->bios[r1_bio->read_disk];
1996 struct page **pages = get_resync_pages(bio)->pages;
1997 sector_t sect = r1_bio->sector;
1998 int sectors = r1_bio->sectors;
1999 int idx = 0;
2000 struct md_rdev *rdev;
2001
2002 rdev = conf->mirrors[r1_bio->read_disk].rdev;
2003 if (test_bit(FailFast, &rdev->flags)) {
2004 /* Don't try recovering from here - just fail it
2005 * ... unless it is the last working device of course */
2006 md_error(mddev, rdev);
2007 if (test_bit(Faulty, &rdev->flags))
2008 /* Don't try to read from here, but make sure
2009 * put_buf does it's thing
2010 */
2011 bio->bi_end_io = end_sync_write;
2012 }
2013
2014 while(sectors) {
2015 int s = sectors;
2016 int d = r1_bio->read_disk;
2017 int success = 0;
2018 int start;
2019
2020 if (s > (PAGE_SIZE>>9))
2021 s = PAGE_SIZE >> 9;
2022 do {
2023 if (r1_bio->bios[d]->bi_end_io == end_sync_read) {
2024 /* No rcu protection needed here devices
2025 * can only be removed when no resync is
2026 * active, and resync is currently active
2027 */
2028 rdev = conf->mirrors[d].rdev;
2029 if (sync_page_io(rdev, sect, s<<9,
2030 pages[idx],
2031 REQ_OP_READ, 0, false)) {
2032 success = 1;
2033 break;
2034 }
2035 }
2036 d++;
2037 if (d == conf->raid_disks * 2)
2038 d = 0;
2039 } while (!success && d != r1_bio->read_disk);
2040
2041 if (!success) {
2042 char b[BDEVNAME_SIZE];
2043 int abort = 0;
2044 /* Cannot read from anywhere, this block is lost.
2045 * Record a bad block on each device. If that doesn't
2046 * work just disable and interrupt the recovery.
2047 * Don't fail devices as that won't really help.
2048 */
2049 pr_crit_ratelimited("md/raid1:%s: %s: unrecoverable I/O read error for block %llu\n",
2050 mdname(mddev), bio_devname(bio, b),
2051 (unsigned long long)r1_bio->sector);
2052 for (d = 0; d < conf->raid_disks * 2; d++) {
2053 rdev = conf->mirrors[d].rdev;
2054 if (!rdev || test_bit(Faulty, &rdev->flags))
2055 continue;
2056 if (!rdev_set_badblocks(rdev, sect, s, 0))
2057 abort = 1;
2058 }
2059 if (abort) {
2060 conf->recovery_disabled =
2061 mddev->recovery_disabled;
2062 set_bit(MD_RECOVERY_INTR, &mddev->recovery);
2063 md_done_sync(mddev, r1_bio->sectors, 0);
2064 put_buf(r1_bio);
2065 return 0;
2066 }
2067 /* Try next page */
2068 sectors -= s;
2069 sect += s;
2070 idx++;
2071 continue;
2072 }
2073
2074 start = d;
2075 /* write it back and re-read */
2076 while (d != r1_bio->read_disk) {
2077 if (d == 0)
2078 d = conf->raid_disks * 2;
2079 d--;
2080 if (r1_bio->bios[d]->bi_end_io != end_sync_read)
2081 continue;
2082 rdev = conf->mirrors[d].rdev;
2083 if (r1_sync_page_io(rdev, sect, s,
2084 pages[idx],
2085 WRITE) == 0) {
2086 r1_bio->bios[d]->bi_end_io = NULL;
2087 rdev_dec_pending(rdev, mddev);
2088 }
2089 }
2090 d = start;
2091 while (d != r1_bio->read_disk) {
2092 if (d == 0)
2093 d = conf->raid_disks * 2;
2094 d--;
2095 if (r1_bio->bios[d]->bi_end_io != end_sync_read)
2096 continue;
2097 rdev = conf->mirrors[d].rdev;
2098 if (r1_sync_page_io(rdev, sect, s,
2099 pages[idx],
2100 READ) != 0)
2101 atomic_add(s, &rdev->corrected_errors);
2102 }
2103 sectors -= s;
2104 sect += s;
2105 idx ++;
2106 }
2107 set_bit(R1BIO_Uptodate, &r1_bio->state);
2108 bio->bi_status = 0;
2109 return 1;
2110}
2111
2112static void process_checks(struct r1bio *r1_bio)
2113{
2114 /* We have read all readable devices. If we haven't
2115 * got the block, then there is no hope left.
2116 * If we have, then we want to do a comparison
2117 * and skip the write if everything is the same.
2118 * If any blocks failed to read, then we need to
2119 * attempt an over-write
2120 */
2121 struct mddev *mddev = r1_bio->mddev;
2122 struct r1conf *conf = mddev->private;
2123 int primary;
2124 int i;
2125 int vcnt;
2126
2127 /* Fix variable parts of all bios */
2128 vcnt = (r1_bio->sectors + PAGE_SIZE / 512 - 1) >> (PAGE_SHIFT - 9);
2129 for (i = 0; i < conf->raid_disks * 2; i++) {
2130 blk_status_t status;
2131 struct bio *b = r1_bio->bios[i];
2132 struct resync_pages *rp = get_resync_pages(b);
2133 if (b->bi_end_io != end_sync_read)
2134 continue;
2135 /* fixup the bio for reuse, but preserve errno */
2136 status = b->bi_status;
2137 bio_reset(b);
2138 b->bi_status = status;
2139 b->bi_iter.bi_sector = r1_bio->sector +
2140 conf->mirrors[i].rdev->data_offset;
2141 bio_set_dev(b, conf->mirrors[i].rdev->bdev);
2142 b->bi_end_io = end_sync_read;
2143 rp->raid_bio = r1_bio;
2144 b->bi_private = rp;
2145
2146 /* initialize bvec table again */
2147 md_bio_reset_resync_pages(b, rp, r1_bio->sectors << 9);
2148 }
2149 for (primary = 0; primary < conf->raid_disks * 2; primary++)
2150 if (r1_bio->bios[primary]->bi_end_io == end_sync_read &&
2151 !r1_bio->bios[primary]->bi_status) {
2152 r1_bio->bios[primary]->bi_end_io = NULL;
2153 rdev_dec_pending(conf->mirrors[primary].rdev, mddev);
2154 break;
2155 }
2156 r1_bio->read_disk = primary;
2157 for (i = 0; i < conf->raid_disks * 2; i++) {
2158 int j = 0;
2159 struct bio *pbio = r1_bio->bios[primary];
2160 struct bio *sbio = r1_bio->bios[i];
2161 blk_status_t status = sbio->bi_status;
2162 struct page **ppages = get_resync_pages(pbio)->pages;
2163 struct page **spages = get_resync_pages(sbio)->pages;
2164 struct bio_vec *bi;
2165 int page_len[RESYNC_PAGES] = { 0 };
2166 struct bvec_iter_all iter_all;
2167
2168 if (sbio->bi_end_io != end_sync_read)
2169 continue;
2170 /* Now we can 'fixup' the error value */
2171 sbio->bi_status = 0;
2172
2173 bio_for_each_segment_all(bi, sbio, iter_all)
2174 page_len[j++] = bi->bv_len;
2175
2176 if (!status) {
2177 for (j = vcnt; j-- ; ) {
2178 if (memcmp(page_address(ppages[j]),
2179 page_address(spages[j]),
2180 page_len[j]))
2181 break;
2182 }
2183 } else
2184 j = 0;
2185 if (j >= 0)
2186 atomic64_add(r1_bio->sectors, &mddev->resync_mismatches);
2187 if (j < 0 || (test_bit(MD_RECOVERY_CHECK, &mddev->recovery)
2188 && !status)) {
2189 /* No need to write to this device. */
2190 sbio->bi_end_io = NULL;
2191 rdev_dec_pending(conf->mirrors[i].rdev, mddev);
2192 continue;
2193 }
2194
2195 bio_copy_data(sbio, pbio);
2196 }
2197}
2198
2199static void sync_request_write(struct mddev *mddev, struct r1bio *r1_bio)
2200{
2201 struct r1conf *conf = mddev->private;
2202 int i;
2203 int disks = conf->raid_disks * 2;
2204 struct bio *wbio;
2205
2206 if (!test_bit(R1BIO_Uptodate, &r1_bio->state))
2207 /* ouch - failed to read all of that. */
2208 if (!fix_sync_read_error(r1_bio))
2209 return;
2210
2211 if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
2212 process_checks(r1_bio);
2213
2214 /*
2215 * schedule writes
2216 */
2217 atomic_set(&r1_bio->remaining, 1);
2218 for (i = 0; i < disks ; i++) {
2219 wbio = r1_bio->bios[i];
2220 if (wbio->bi_end_io == NULL ||
2221 (wbio->bi_end_io == end_sync_read &&
2222 (i == r1_bio->read_disk ||
2223 !test_bit(MD_RECOVERY_SYNC, &mddev->recovery))))
2224 continue;
2225 if (test_bit(Faulty, &conf->mirrors[i].rdev->flags)) {
2226 abort_sync_write(mddev, r1_bio);
2227 continue;
2228 }
2229
2230 bio_set_op_attrs(wbio, REQ_OP_WRITE, 0);
2231 if (test_bit(FailFast, &conf->mirrors[i].rdev->flags))
2232 wbio->bi_opf |= MD_FAILFAST;
2233
2234 wbio->bi_end_io = end_sync_write;
2235 atomic_inc(&r1_bio->remaining);
2236 md_sync_acct(conf->mirrors[i].rdev->bdev, bio_sectors(wbio));
2237
2238 submit_bio_noacct(wbio);
2239 }
2240
2241 put_sync_write_buf(r1_bio, 1);
2242}
2243
2244/*
2245 * This is a kernel thread which:
2246 *
2247 * 1. Retries failed read operations on working mirrors.
2248 * 2. Updates the raid superblock when problems encounter.
2249 * 3. Performs writes following reads for array synchronising.
2250 */
2251
2252static void fix_read_error(struct r1conf *conf, int read_disk,
2253 sector_t sect, int sectors)
2254{
2255 struct mddev *mddev = conf->mddev;
2256 while(sectors) {
2257 int s = sectors;
2258 int d = read_disk;
2259 int success = 0;
2260 int start;
2261 struct md_rdev *rdev;
2262
2263 if (s > (PAGE_SIZE>>9))
2264 s = PAGE_SIZE >> 9;
2265
2266 do {
2267 sector_t first_bad;
2268 int bad_sectors;
2269
2270 rcu_read_lock();
2271 rdev = rcu_dereference(conf->mirrors[d].rdev);
2272 if (rdev &&
2273 (test_bit(In_sync, &rdev->flags) ||
2274 (!test_bit(Faulty, &rdev->flags) &&
2275 rdev->recovery_offset >= sect + s)) &&
2276 is_badblock(rdev, sect, s,
2277 &first_bad, &bad_sectors) == 0) {
2278 atomic_inc(&rdev->nr_pending);
2279 rcu_read_unlock();
2280 if (sync_page_io(rdev, sect, s<<9,
2281 conf->tmppage, REQ_OP_READ, 0, false))
2282 success = 1;
2283 rdev_dec_pending(rdev, mddev);
2284 if (success)
2285 break;
2286 } else
2287 rcu_read_unlock();
2288 d++;
2289 if (d == conf->raid_disks * 2)
2290 d = 0;
2291 } while (!success && d != read_disk);
2292
2293 if (!success) {
2294 /* Cannot read from anywhere - mark it bad */
2295 struct md_rdev *rdev = conf->mirrors[read_disk].rdev;
2296 if (!rdev_set_badblocks(rdev, sect, s, 0))
2297 md_error(mddev, rdev);
2298 break;
2299 }
2300 /* write it back and re-read */
2301 start = d;
2302 while (d != read_disk) {
2303 if (d==0)
2304 d = conf->raid_disks * 2;
2305 d--;
2306 rcu_read_lock();
2307 rdev = rcu_dereference(conf->mirrors[d].rdev);
2308 if (rdev &&
2309 !test_bit(Faulty, &rdev->flags)) {
2310 atomic_inc(&rdev->nr_pending);
2311 rcu_read_unlock();
2312 r1_sync_page_io(rdev, sect, s,
2313 conf->tmppage, WRITE);
2314 rdev_dec_pending(rdev, mddev);
2315 } else
2316 rcu_read_unlock();
2317 }
2318 d = start;
2319 while (d != read_disk) {
2320 char b[BDEVNAME_SIZE];
2321 if (d==0)
2322 d = conf->raid_disks * 2;
2323 d--;
2324 rcu_read_lock();
2325 rdev = rcu_dereference(conf->mirrors[d].rdev);
2326 if (rdev &&
2327 !test_bit(Faulty, &rdev->flags)) {
2328 atomic_inc(&rdev->nr_pending);
2329 rcu_read_unlock();
2330 if (r1_sync_page_io(rdev, sect, s,
2331 conf->tmppage, READ)) {
2332 atomic_add(s, &rdev->corrected_errors);
2333 pr_info("md/raid1:%s: read error corrected (%d sectors at %llu on %s)\n",
2334 mdname(mddev), s,
2335 (unsigned long long)(sect +
2336 rdev->data_offset),
2337 bdevname(rdev->bdev, b));
2338 }
2339 rdev_dec_pending(rdev, mddev);
2340 } else
2341 rcu_read_unlock();
2342 }
2343 sectors -= s;
2344 sect += s;
2345 }
2346}
2347
2348static int narrow_write_error(struct r1bio *r1_bio, int i)
2349{
2350 struct mddev *mddev = r1_bio->mddev;
2351 struct r1conf *conf = mddev->private;
2352 struct md_rdev *rdev = conf->mirrors[i].rdev;
2353
2354 /* bio has the data to be written to device 'i' where
2355 * we just recently had a write error.
2356 * We repeatedly clone the bio and trim down to one block,
2357 * then try the write. Where the write fails we record
2358 * a bad block.
2359 * It is conceivable that the bio doesn't exactly align with
2360 * blocks. We must handle this somehow.
2361 *
2362 * We currently own a reference on the rdev.
2363 */
2364
2365 int block_sectors;
2366 sector_t sector;
2367 int sectors;
2368 int sect_to_write = r1_bio->sectors;
2369 int ok = 1;
2370
2371 if (rdev->badblocks.shift < 0)
2372 return 0;
2373
2374 block_sectors = roundup(1 << rdev->badblocks.shift,
2375 bdev_logical_block_size(rdev->bdev) >> 9);
2376 sector = r1_bio->sector;
2377 sectors = ((sector + block_sectors)
2378 & ~(sector_t)(block_sectors - 1))
2379 - sector;
2380
2381 while (sect_to_write) {
2382 struct bio *wbio;
2383 if (sectors > sect_to_write)
2384 sectors = sect_to_write;
2385 /* Write at 'sector' for 'sectors'*/
2386
2387 if (test_bit(R1BIO_BehindIO, &r1_bio->state)) {
2388 wbio = bio_clone_fast(r1_bio->behind_master_bio,
2389 GFP_NOIO,
2390 &mddev->bio_set);
2391 } else {
2392 wbio = bio_clone_fast(r1_bio->master_bio, GFP_NOIO,
2393 &mddev->bio_set);
2394 }
2395
2396 bio_set_op_attrs(wbio, REQ_OP_WRITE, 0);
2397 wbio->bi_iter.bi_sector = r1_bio->sector;
2398 wbio->bi_iter.bi_size = r1_bio->sectors << 9;
2399
2400 bio_trim(wbio, sector - r1_bio->sector, sectors);
2401 wbio->bi_iter.bi_sector += rdev->data_offset;
2402 bio_set_dev(wbio, rdev->bdev);
2403
2404 if (submit_bio_wait(wbio) < 0)
2405 /* failure! */
2406 ok = rdev_set_badblocks(rdev, sector,
2407 sectors, 0)
2408 && ok;
2409
2410 bio_put(wbio);
2411 sect_to_write -= sectors;
2412 sector += sectors;
2413 sectors = block_sectors;
2414 }
2415 return ok;
2416}
2417
2418static void handle_sync_write_finished(struct r1conf *conf, struct r1bio *r1_bio)
2419{
2420 int m;
2421 int s = r1_bio->sectors;
2422 for (m = 0; m < conf->raid_disks * 2 ; m++) {
2423 struct md_rdev *rdev = conf->mirrors[m].rdev;
2424 struct bio *bio = r1_bio->bios[m];
2425 if (bio->bi_end_io == NULL)
2426 continue;
2427 if (!bio->bi_status &&
2428 test_bit(R1BIO_MadeGood, &r1_bio->state)) {
2429 rdev_clear_badblocks(rdev, r1_bio->sector, s, 0);
2430 }
2431 if (bio->bi_status &&
2432 test_bit(R1BIO_WriteError, &r1_bio->state)) {
2433 if (!rdev_set_badblocks(rdev, r1_bio->sector, s, 0))
2434 md_error(conf->mddev, rdev);
2435 }
2436 }
2437 put_buf(r1_bio);
2438 md_done_sync(conf->mddev, s, 1);
2439}
2440
2441static void handle_write_finished(struct r1conf *conf, struct r1bio *r1_bio)
2442{
2443 int m, idx;
2444 bool fail = false;
2445
2446 for (m = 0; m < conf->raid_disks * 2 ; m++)
2447 if (r1_bio->bios[m] == IO_MADE_GOOD) {
2448 struct md_rdev *rdev = conf->mirrors[m].rdev;
2449 rdev_clear_badblocks(rdev,
2450 r1_bio->sector,
2451 r1_bio->sectors, 0);
2452 rdev_dec_pending(rdev, conf->mddev);
2453 } else if (r1_bio->bios[m] != NULL) {
2454 /* This drive got a write error. We need to
2455 * narrow down and record precise write
2456 * errors.
2457 */
2458 fail = true;
2459 if (!narrow_write_error(r1_bio, m)) {
2460 md_error(conf->mddev,
2461 conf->mirrors[m].rdev);
2462 /* an I/O failed, we can't clear the bitmap */
2463 set_bit(R1BIO_Degraded, &r1_bio->state);
2464 }
2465 rdev_dec_pending(conf->mirrors[m].rdev,
2466 conf->mddev);
2467 }
2468 if (fail) {
2469 spin_lock_irq(&conf->device_lock);
2470 list_add(&r1_bio->retry_list, &conf->bio_end_io_list);
2471 idx = sector_to_idx(r1_bio->sector);
2472 atomic_inc(&conf->nr_queued[idx]);
2473 spin_unlock_irq(&conf->device_lock);
2474 /*
2475 * In case freeze_array() is waiting for condition
2476 * get_unqueued_pending() == extra to be true.
2477 */
2478 wake_up(&conf->wait_barrier);
2479 md_wakeup_thread(conf->mddev->thread);
2480 } else {
2481 if (test_bit(R1BIO_WriteError, &r1_bio->state))
2482 close_write(r1_bio);
2483 raid_end_bio_io(r1_bio);
2484 }
2485}
2486
2487static void handle_read_error(struct r1conf *conf, struct r1bio *r1_bio)
2488{
2489 struct mddev *mddev = conf->mddev;
2490 struct bio *bio;
2491 struct md_rdev *rdev;
2492
2493 clear_bit(R1BIO_ReadError, &r1_bio->state);
2494 /* we got a read error. Maybe the drive is bad. Maybe just
2495 * the block and we can fix it.
2496 * We freeze all other IO, and try reading the block from
2497 * other devices. When we find one, we re-write
2498 * and check it that fixes the read error.
2499 * This is all done synchronously while the array is
2500 * frozen
2501 */
2502
2503 bio = r1_bio->bios[r1_bio->read_disk];
2504 bio_put(bio);
2505 r1_bio->bios[r1_bio->read_disk] = NULL;
2506
2507 rdev = conf->mirrors[r1_bio->read_disk].rdev;
2508 if (mddev->ro == 0
2509 && !test_bit(FailFast, &rdev->flags)) {
2510 freeze_array(conf, 1);
2511 fix_read_error(conf, r1_bio->read_disk,
2512 r1_bio->sector, r1_bio->sectors);
2513 unfreeze_array(conf);
2514 } else if (mddev->ro == 0 && test_bit(FailFast, &rdev->flags)) {
2515 md_error(mddev, rdev);
2516 } else {
2517 r1_bio->bios[r1_bio->read_disk] = IO_BLOCKED;
2518 }
2519
2520 rdev_dec_pending(rdev, conf->mddev);
2521 allow_barrier(conf, r1_bio->sector);
2522 bio = r1_bio->master_bio;
2523
2524 /* Reuse the old r1_bio so that the IO_BLOCKED settings are preserved */
2525 r1_bio->state = 0;
2526 raid1_read_request(mddev, bio, r1_bio->sectors, r1_bio);
2527}
2528
2529static void raid1d(struct md_thread *thread)
2530{
2531 struct mddev *mddev = thread->mddev;
2532 struct r1bio *r1_bio;
2533 unsigned long flags;
2534 struct r1conf *conf = mddev->private;
2535 struct list_head *head = &conf->retry_list;
2536 struct blk_plug plug;
2537 int idx;
2538
2539 md_check_recovery(mddev);
2540
2541 if (!list_empty_careful(&conf->bio_end_io_list) &&
2542 !test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags)) {
2543 LIST_HEAD(tmp);
2544 spin_lock_irqsave(&conf->device_lock, flags);
2545 if (!test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags))
2546 list_splice_init(&conf->bio_end_io_list, &tmp);
2547 spin_unlock_irqrestore(&conf->device_lock, flags);
2548 while (!list_empty(&tmp)) {
2549 r1_bio = list_first_entry(&tmp, struct r1bio,
2550 retry_list);
2551 list_del(&r1_bio->retry_list);
2552 idx = sector_to_idx(r1_bio->sector);
2553 atomic_dec(&conf->nr_queued[idx]);
2554 if (mddev->degraded)
2555 set_bit(R1BIO_Degraded, &r1_bio->state);
2556 if (test_bit(R1BIO_WriteError, &r1_bio->state))
2557 close_write(r1_bio);
2558 raid_end_bio_io(r1_bio);
2559 }
2560 }
2561
2562 blk_start_plug(&plug);
2563 for (;;) {
2564
2565 flush_pending_writes(conf);
2566
2567 spin_lock_irqsave(&conf->device_lock, flags);
2568 if (list_empty(head)) {
2569 spin_unlock_irqrestore(&conf->device_lock, flags);
2570 break;
2571 }
2572 r1_bio = list_entry(head->prev, struct r1bio, retry_list);
2573 list_del(head->prev);
2574 idx = sector_to_idx(r1_bio->sector);
2575 atomic_dec(&conf->nr_queued[idx]);
2576 spin_unlock_irqrestore(&conf->device_lock, flags);
2577
2578 mddev = r1_bio->mddev;
2579 conf = mddev->private;
2580 if (test_bit(R1BIO_IsSync, &r1_bio->state)) {
2581 if (test_bit(R1BIO_MadeGood, &r1_bio->state) ||
2582 test_bit(R1BIO_WriteError, &r1_bio->state))
2583 handle_sync_write_finished(conf, r1_bio);
2584 else
2585 sync_request_write(mddev, r1_bio);
2586 } else if (test_bit(R1BIO_MadeGood, &r1_bio->state) ||
2587 test_bit(R1BIO_WriteError, &r1_bio->state))
2588 handle_write_finished(conf, r1_bio);
2589 else if (test_bit(R1BIO_ReadError, &r1_bio->state))
2590 handle_read_error(conf, r1_bio);
2591 else
2592 WARN_ON_ONCE(1);
2593
2594 cond_resched();
2595 if (mddev->sb_flags & ~(1<<MD_SB_CHANGE_PENDING))
2596 md_check_recovery(mddev);
2597 }
2598 blk_finish_plug(&plug);
2599}
2600
2601static int init_resync(struct r1conf *conf)
2602{
2603 int buffs;
2604
2605 buffs = RESYNC_WINDOW / RESYNC_BLOCK_SIZE;
2606 BUG_ON(mempool_initialized(&conf->r1buf_pool));
2607
2608 return mempool_init(&conf->r1buf_pool, buffs, r1buf_pool_alloc,
2609 r1buf_pool_free, conf->poolinfo);
2610}
2611
2612static struct r1bio *raid1_alloc_init_r1buf(struct r1conf *conf)
2613{
2614 struct r1bio *r1bio = mempool_alloc(&conf->r1buf_pool, GFP_NOIO);
2615 struct resync_pages *rps;
2616 struct bio *bio;
2617 int i;
2618
2619 for (i = conf->poolinfo->raid_disks; i--; ) {
2620 bio = r1bio->bios[i];
2621 rps = bio->bi_private;
2622 bio_reset(bio);
2623 bio->bi_private = rps;
2624 }
2625 r1bio->master_bio = NULL;
2626 return r1bio;
2627}
2628
2629/*
2630 * perform a "sync" on one "block"
2631 *
2632 * We need to make sure that no normal I/O request - particularly write
2633 * requests - conflict with active sync requests.
2634 *
2635 * This is achieved by tracking pending requests and a 'barrier' concept
2636 * that can be installed to exclude normal IO requests.
2637 */
2638
2639static sector_t raid1_sync_request(struct mddev *mddev, sector_t sector_nr,
2640 int *skipped)
2641{
2642 struct r1conf *conf = mddev->private;
2643 struct r1bio *r1_bio;
2644 struct bio *bio;
2645 sector_t max_sector, nr_sectors;
2646 int disk = -1;
2647 int i;
2648 int wonly = -1;
2649 int write_targets = 0, read_targets = 0;
2650 sector_t sync_blocks;
2651 int still_degraded = 0;
2652 int good_sectors = RESYNC_SECTORS;
2653 int min_bad = 0; /* number of sectors that are bad in all devices */
2654 int idx = sector_to_idx(sector_nr);
2655 int page_idx = 0;
2656
2657 if (!mempool_initialized(&conf->r1buf_pool))
2658 if (init_resync(conf))
2659 return 0;
2660
2661 max_sector = mddev->dev_sectors;
2662 if (sector_nr >= max_sector) {
2663 /* If we aborted, we need to abort the
2664 * sync on the 'current' bitmap chunk (there will
2665 * only be one in raid1 resync.
2666 * We can find the current addess in mddev->curr_resync
2667 */
2668 if (mddev->curr_resync < max_sector) /* aborted */
2669 md_bitmap_end_sync(mddev->bitmap, mddev->curr_resync,
2670 &sync_blocks, 1);
2671 else /* completed sync */
2672 conf->fullsync = 0;
2673
2674 md_bitmap_close_sync(mddev->bitmap);
2675 close_sync(conf);
2676
2677 if (mddev_is_clustered(mddev)) {
2678 conf->cluster_sync_low = 0;
2679 conf->cluster_sync_high = 0;
2680 }
2681 return 0;
2682 }
2683
2684 if (mddev->bitmap == NULL &&
2685 mddev->recovery_cp == MaxSector &&
2686 !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery) &&
2687 conf->fullsync == 0) {
2688 *skipped = 1;
2689 return max_sector - sector_nr;
2690 }
2691 /* before building a request, check if we can skip these blocks..
2692 * This call the bitmap_start_sync doesn't actually record anything
2693 */
2694 if (!md_bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, 1) &&
2695 !conf->fullsync && !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) {
2696 /* We can skip this block, and probably several more */
2697 *skipped = 1;
2698 return sync_blocks;
2699 }
2700
2701 /*
2702 * If there is non-resync activity waiting for a turn, then let it
2703 * though before starting on this new sync request.
2704 */
2705 if (atomic_read(&conf->nr_waiting[idx]))
2706 schedule_timeout_uninterruptible(1);
2707
2708 /* we are incrementing sector_nr below. To be safe, we check against
2709 * sector_nr + two times RESYNC_SECTORS
2710 */
2711
2712 md_bitmap_cond_end_sync(mddev->bitmap, sector_nr,
2713 mddev_is_clustered(mddev) && (sector_nr + 2 * RESYNC_SECTORS > conf->cluster_sync_high));
2714
2715
2716 if (raise_barrier(conf, sector_nr))
2717 return 0;
2718
2719 r1_bio = raid1_alloc_init_r1buf(conf);
2720
2721 rcu_read_lock();
2722 /*
2723 * If we get a correctably read error during resync or recovery,
2724 * we might want to read from a different device. So we
2725 * flag all drives that could conceivably be read from for READ,
2726 * and any others (which will be non-In_sync devices) for WRITE.
2727 * If a read fails, we try reading from something else for which READ
2728 * is OK.
2729 */
2730
2731 r1_bio->mddev = mddev;
2732 r1_bio->sector = sector_nr;
2733 r1_bio->state = 0;
2734 set_bit(R1BIO_IsSync, &r1_bio->state);
2735 /* make sure good_sectors won't go across barrier unit boundary */
2736 good_sectors = align_to_barrier_unit_end(sector_nr, good_sectors);
2737
2738 for (i = 0; i < conf->raid_disks * 2; i++) {
2739 struct md_rdev *rdev;
2740 bio = r1_bio->bios[i];
2741
2742 rdev = rcu_dereference(conf->mirrors[i].rdev);
2743 if (rdev == NULL ||
2744 test_bit(Faulty, &rdev->flags)) {
2745 if (i < conf->raid_disks)
2746 still_degraded = 1;
2747 } else if (!test_bit(In_sync, &rdev->flags)) {
2748 bio_set_op_attrs(bio, REQ_OP_WRITE, 0);
2749 bio->bi_end_io = end_sync_write;
2750 write_targets ++;
2751 } else {
2752 /* may need to read from here */
2753 sector_t first_bad = MaxSector;
2754 int bad_sectors;
2755
2756 if (is_badblock(rdev, sector_nr, good_sectors,
2757 &first_bad, &bad_sectors)) {
2758 if (first_bad > sector_nr)
2759 good_sectors = first_bad - sector_nr;
2760 else {
2761 bad_sectors -= (sector_nr - first_bad);
2762 if (min_bad == 0 ||
2763 min_bad > bad_sectors)
2764 min_bad = bad_sectors;
2765 }
2766 }
2767 if (sector_nr < first_bad) {
2768 if (test_bit(WriteMostly, &rdev->flags)) {
2769 if (wonly < 0)
2770 wonly = i;
2771 } else {
2772 if (disk < 0)
2773 disk = i;
2774 }
2775 bio_set_op_attrs(bio, REQ_OP_READ, 0);
2776 bio->bi_end_io = end_sync_read;
2777 read_targets++;
2778 } else if (!test_bit(WriteErrorSeen, &rdev->flags) &&
2779 test_bit(MD_RECOVERY_SYNC, &mddev->recovery) &&
2780 !test_bit(MD_RECOVERY_CHECK, &mddev->recovery)) {
2781 /*
2782 * The device is suitable for reading (InSync),
2783 * but has bad block(s) here. Let's try to correct them,
2784 * if we are doing resync or repair. Otherwise, leave
2785 * this device alone for this sync request.
2786 */
2787 bio_set_op_attrs(bio, REQ_OP_WRITE, 0);
2788 bio->bi_end_io = end_sync_write;
2789 write_targets++;
2790 }
2791 }
2792 if (rdev && bio->bi_end_io) {
2793 atomic_inc(&rdev->nr_pending);
2794 bio->bi_iter.bi_sector = sector_nr + rdev->data_offset;
2795 bio_set_dev(bio, rdev->bdev);
2796 if (test_bit(FailFast, &rdev->flags))
2797 bio->bi_opf |= MD_FAILFAST;
2798 }
2799 }
2800 rcu_read_unlock();
2801 if (disk < 0)
2802 disk = wonly;
2803 r1_bio->read_disk = disk;
2804
2805 if (read_targets == 0 && min_bad > 0) {
2806 /* These sectors are bad on all InSync devices, so we
2807 * need to mark them bad on all write targets
2808 */
2809 int ok = 1;
2810 for (i = 0 ; i < conf->raid_disks * 2 ; i++)
2811 if (r1_bio->bios[i]->bi_end_io == end_sync_write) {
2812 struct md_rdev *rdev = conf->mirrors[i].rdev;
2813 ok = rdev_set_badblocks(rdev, sector_nr,
2814 min_bad, 0
2815 ) && ok;
2816 }
2817 set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
2818 *skipped = 1;
2819 put_buf(r1_bio);
2820
2821 if (!ok) {
2822 /* Cannot record the badblocks, so need to
2823 * abort the resync.
2824 * If there are multiple read targets, could just
2825 * fail the really bad ones ???
2826 */
2827 conf->recovery_disabled = mddev->recovery_disabled;
2828 set_bit(MD_RECOVERY_INTR, &mddev->recovery);
2829 return 0;
2830 } else
2831 return min_bad;
2832
2833 }
2834 if (min_bad > 0 && min_bad < good_sectors) {
2835 /* only resync enough to reach the next bad->good
2836 * transition */
2837 good_sectors = min_bad;
2838 }
2839
2840 if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) && read_targets > 0)
2841 /* extra read targets are also write targets */
2842 write_targets += read_targets-1;
2843
2844 if (write_targets == 0 || read_targets == 0) {
2845 /* There is nowhere to write, so all non-sync
2846 * drives must be failed - so we are finished
2847 */
2848 sector_t rv;
2849 if (min_bad > 0)
2850 max_sector = sector_nr + min_bad;
2851 rv = max_sector - sector_nr;
2852 *skipped = 1;
2853 put_buf(r1_bio);
2854 return rv;
2855 }
2856
2857 if (max_sector > mddev->resync_max)
2858 max_sector = mddev->resync_max; /* Don't do IO beyond here */
2859 if (max_sector > sector_nr + good_sectors)
2860 max_sector = sector_nr + good_sectors;
2861 nr_sectors = 0;
2862 sync_blocks = 0;
2863 do {
2864 struct page *page;
2865 int len = PAGE_SIZE;
2866 if (sector_nr + (len>>9) > max_sector)
2867 len = (max_sector - sector_nr) << 9;
2868 if (len == 0)
2869 break;
2870 if (sync_blocks == 0) {
2871 if (!md_bitmap_start_sync(mddev->bitmap, sector_nr,
2872 &sync_blocks, still_degraded) &&
2873 !conf->fullsync &&
2874 !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
2875 break;
2876 if ((len >> 9) > sync_blocks)
2877 len = sync_blocks<<9;
2878 }
2879
2880 for (i = 0 ; i < conf->raid_disks * 2; i++) {
2881 struct resync_pages *rp;
2882
2883 bio = r1_bio->bios[i];
2884 rp = get_resync_pages(bio);
2885 if (bio->bi_end_io) {
2886 page = resync_fetch_page(rp, page_idx);
2887
2888 /*
2889 * won't fail because the vec table is big
2890 * enough to hold all these pages
2891 */
2892 bio_add_page(bio, page, len, 0);
2893 }
2894 }
2895 nr_sectors += len>>9;
2896 sector_nr += len>>9;
2897 sync_blocks -= (len>>9);
2898 } while (++page_idx < RESYNC_PAGES);
2899
2900 r1_bio->sectors = nr_sectors;
2901
2902 if (mddev_is_clustered(mddev) &&
2903 conf->cluster_sync_high < sector_nr + nr_sectors) {
2904 conf->cluster_sync_low = mddev->curr_resync_completed;
2905 conf->cluster_sync_high = conf->cluster_sync_low + CLUSTER_RESYNC_WINDOW_SECTORS;
2906 /* Send resync message */
2907 md_cluster_ops->resync_info_update(mddev,
2908 conf->cluster_sync_low,
2909 conf->cluster_sync_high);
2910 }
2911
2912 /* For a user-requested sync, we read all readable devices and do a
2913 * compare
2914 */
2915 if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) {
2916 atomic_set(&r1_bio->remaining, read_targets);
2917 for (i = 0; i < conf->raid_disks * 2 && read_targets; i++) {
2918 bio = r1_bio->bios[i];
2919 if (bio->bi_end_io == end_sync_read) {
2920 read_targets--;
2921 md_sync_acct_bio(bio, nr_sectors);
2922 if (read_targets == 1)
2923 bio->bi_opf &= ~MD_FAILFAST;
2924 submit_bio_noacct(bio);
2925 }
2926 }
2927 } else {
2928 atomic_set(&r1_bio->remaining, 1);
2929 bio = r1_bio->bios[r1_bio->read_disk];
2930 md_sync_acct_bio(bio, nr_sectors);
2931 if (read_targets == 1)
2932 bio->bi_opf &= ~MD_FAILFAST;
2933 submit_bio_noacct(bio);
2934 }
2935 return nr_sectors;
2936}
2937
2938static sector_t raid1_size(struct mddev *mddev, sector_t sectors, int raid_disks)
2939{
2940 if (sectors)
2941 return sectors;
2942
2943 return mddev->dev_sectors;
2944}
2945
2946static struct r1conf *setup_conf(struct mddev *mddev)
2947{
2948 struct r1conf *conf;
2949 int i;
2950 struct raid1_info *disk;
2951 struct md_rdev *rdev;
2952 int err = -ENOMEM;
2953
2954 conf = kzalloc(sizeof(struct r1conf), GFP_KERNEL);
2955 if (!conf)
2956 goto abort;
2957
2958 conf->nr_pending = kcalloc(BARRIER_BUCKETS_NR,
2959 sizeof(atomic_t), GFP_KERNEL);
2960 if (!conf->nr_pending)
2961 goto abort;
2962
2963 conf->nr_waiting = kcalloc(BARRIER_BUCKETS_NR,
2964 sizeof(atomic_t), GFP_KERNEL);
2965 if (!conf->nr_waiting)
2966 goto abort;
2967
2968 conf->nr_queued = kcalloc(BARRIER_BUCKETS_NR,
2969 sizeof(atomic_t), GFP_KERNEL);
2970 if (!conf->nr_queued)
2971 goto abort;
2972
2973 conf->barrier = kcalloc(BARRIER_BUCKETS_NR,
2974 sizeof(atomic_t), GFP_KERNEL);
2975 if (!conf->barrier)
2976 goto abort;
2977
2978 conf->mirrors = kzalloc(array3_size(sizeof(struct raid1_info),
2979 mddev->raid_disks, 2),
2980 GFP_KERNEL);
2981 if (!conf->mirrors)
2982 goto abort;
2983
2984 conf->tmppage = alloc_page(GFP_KERNEL);
2985 if (!conf->tmppage)
2986 goto abort;
2987
2988 conf->poolinfo = kzalloc(sizeof(*conf->poolinfo), GFP_KERNEL);
2989 if (!conf->poolinfo)
2990 goto abort;
2991 conf->poolinfo->raid_disks = mddev->raid_disks * 2;
2992 err = mempool_init(&conf->r1bio_pool, NR_RAID_BIOS, r1bio_pool_alloc,
2993 rbio_pool_free, conf->poolinfo);
2994 if (err)
2995 goto abort;
2996
2997 err = bioset_init(&conf->bio_split, BIO_POOL_SIZE, 0, 0);
2998 if (err)
2999 goto abort;
3000
3001 conf->poolinfo->mddev = mddev;
3002
3003 err = -EINVAL;
3004 spin_lock_init(&conf->device_lock);
3005 rdev_for_each(rdev, mddev) {
3006 int disk_idx = rdev->raid_disk;
3007 if (disk_idx >= mddev->raid_disks
3008 || disk_idx < 0)
3009 continue;
3010 if (test_bit(Replacement, &rdev->flags))
3011 disk = conf->mirrors + mddev->raid_disks + disk_idx;
3012 else
3013 disk = conf->mirrors + disk_idx;
3014
3015 if (disk->rdev)
3016 goto abort;
3017 disk->rdev = rdev;
3018 disk->head_position = 0;
3019 disk->seq_start = MaxSector;
3020 }
3021 conf->raid_disks = mddev->raid_disks;
3022 conf->mddev = mddev;
3023 INIT_LIST_HEAD(&conf->retry_list);
3024 INIT_LIST_HEAD(&conf->bio_end_io_list);
3025
3026 spin_lock_init(&conf->resync_lock);
3027 init_waitqueue_head(&conf->wait_barrier);
3028
3029 bio_list_init(&conf->pending_bio_list);
3030 conf->pending_count = 0;
3031 conf->recovery_disabled = mddev->recovery_disabled - 1;
3032
3033 err = -EIO;
3034 for (i = 0; i < conf->raid_disks * 2; i++) {
3035
3036 disk = conf->mirrors + i;
3037
3038 if (i < conf->raid_disks &&
3039 disk[conf->raid_disks].rdev) {
3040 /* This slot has a replacement. */
3041 if (!disk->rdev) {
3042 /* No original, just make the replacement
3043 * a recovering spare
3044 */
3045 disk->rdev =
3046 disk[conf->raid_disks].rdev;
3047 disk[conf->raid_disks].rdev = NULL;
3048 } else if (!test_bit(In_sync, &disk->rdev->flags))
3049 /* Original is not in_sync - bad */
3050 goto abort;
3051 }
3052
3053 if (!disk->rdev ||
3054 !test_bit(In_sync, &disk->rdev->flags)) {
3055 disk->head_position = 0;
3056 if (disk->rdev &&
3057 (disk->rdev->saved_raid_disk < 0))
3058 conf->fullsync = 1;
3059 }
3060 }
3061
3062 err = -ENOMEM;
3063 conf->thread = md_register_thread(raid1d, mddev, "raid1");
3064 if (!conf->thread)
3065 goto abort;
3066
3067 return conf;
3068
3069 abort:
3070 if (conf) {
3071 mempool_exit(&conf->r1bio_pool);
3072 kfree(conf->mirrors);
3073 safe_put_page(conf->tmppage);
3074 kfree(conf->poolinfo);
3075 kfree(conf->nr_pending);
3076 kfree(conf->nr_waiting);
3077 kfree(conf->nr_queued);
3078 kfree(conf->barrier);
3079 bioset_exit(&conf->bio_split);
3080 kfree(conf);
3081 }
3082 return ERR_PTR(err);
3083}
3084
3085static void raid1_free(struct mddev *mddev, void *priv);
3086static int raid1_run(struct mddev *mddev)
3087{
3088 struct r1conf *conf;
3089 int i;
3090 struct md_rdev *rdev;
3091 int ret;
3092 bool discard_supported = false;
3093
3094 if (mddev->level != 1) {
3095 pr_warn("md/raid1:%s: raid level not set to mirroring (%d)\n",
3096 mdname(mddev), mddev->level);
3097 return -EIO;
3098 }
3099 if (mddev->reshape_position != MaxSector) {
3100 pr_warn("md/raid1:%s: reshape_position set but not supported\n",
3101 mdname(mddev));
3102 return -EIO;
3103 }
3104 if (mddev_init_writes_pending(mddev) < 0)
3105 return -ENOMEM;
3106 /*
3107 * copy the already verified devices into our private RAID1
3108 * bookkeeping area. [whatever we allocate in run(),
3109 * should be freed in raid1_free()]
3110 */
3111 if (mddev->private == NULL)
3112 conf = setup_conf(mddev);
3113 else
3114 conf = mddev->private;
3115
3116 if (IS_ERR(conf))
3117 return PTR_ERR(conf);
3118
3119 if (mddev->queue) {
3120 blk_queue_max_write_same_sectors(mddev->queue, 0);
3121 blk_queue_max_write_zeroes_sectors(mddev->queue, 0);
3122 }
3123
3124 rdev_for_each(rdev, mddev) {
3125 if (!mddev->gendisk)
3126 continue;
3127 disk_stack_limits(mddev->gendisk, rdev->bdev,
3128 rdev->data_offset << 9);
3129 if (blk_queue_discard(bdev_get_queue(rdev->bdev)))
3130 discard_supported = true;
3131 }
3132
3133 mddev->degraded = 0;
3134 for (i = 0; i < conf->raid_disks; i++)
3135 if (conf->mirrors[i].rdev == NULL ||
3136 !test_bit(In_sync, &conf->mirrors[i].rdev->flags) ||
3137 test_bit(Faulty, &conf->mirrors[i].rdev->flags))
3138 mddev->degraded++;
3139 /*
3140 * RAID1 needs at least one disk in active
3141 */
3142 if (conf->raid_disks - mddev->degraded < 1) {
3143 ret = -EINVAL;
3144 goto abort;
3145 }
3146
3147 if (conf->raid_disks - mddev->degraded == 1)
3148 mddev->recovery_cp = MaxSector;
3149
3150 if (mddev->recovery_cp != MaxSector)
3151 pr_info("md/raid1:%s: not clean -- starting background reconstruction\n",
3152 mdname(mddev));
3153 pr_info("md/raid1:%s: active with %d out of %d mirrors\n",
3154 mdname(mddev), mddev->raid_disks - mddev->degraded,
3155 mddev->raid_disks);
3156
3157 /*
3158 * Ok, everything is just fine now
3159 */
3160 mddev->thread = conf->thread;
3161 conf->thread = NULL;
3162 mddev->private = conf;
3163 set_bit(MD_FAILFAST_SUPPORTED, &mddev->flags);
3164
3165 md_set_array_sectors(mddev, raid1_size(mddev, 0, 0));
3166
3167 if (mddev->queue) {
3168 if (discard_supported)
3169 blk_queue_flag_set(QUEUE_FLAG_DISCARD,
3170 mddev->queue);
3171 else
3172 blk_queue_flag_clear(QUEUE_FLAG_DISCARD,
3173 mddev->queue);
3174 }
3175
3176 ret = md_integrity_register(mddev);
3177 if (ret) {
3178 md_unregister_thread(&mddev->thread);
3179 goto abort;
3180 }
3181 return 0;
3182
3183abort:
3184 raid1_free(mddev, conf);
3185 return ret;
3186}
3187
3188static void raid1_free(struct mddev *mddev, void *priv)
3189{
3190 struct r1conf *conf = priv;
3191
3192 mempool_exit(&conf->r1bio_pool);
3193 kfree(conf->mirrors);
3194 safe_put_page(conf->tmppage);
3195 kfree(conf->poolinfo);
3196 kfree(conf->nr_pending);
3197 kfree(conf->nr_waiting);
3198 kfree(conf->nr_queued);
3199 kfree(conf->barrier);
3200 bioset_exit(&conf->bio_split);
3201 kfree(conf);
3202}
3203
3204static int raid1_resize(struct mddev *mddev, sector_t sectors)
3205{
3206 /* no resync is happening, and there is enough space
3207 * on all devices, so we can resize.
3208 * We need to make sure resync covers any new space.
3209 * If the array is shrinking we should possibly wait until
3210 * any io in the removed space completes, but it hardly seems
3211 * worth it.
3212 */
3213 sector_t newsize = raid1_size(mddev, sectors, 0);
3214 if (mddev->external_size &&
3215 mddev->array_sectors > newsize)
3216 return -EINVAL;
3217 if (mddev->bitmap) {
3218 int ret = md_bitmap_resize(mddev->bitmap, newsize, 0, 0);
3219 if (ret)
3220 return ret;
3221 }
3222 md_set_array_sectors(mddev, newsize);
3223 if (sectors > mddev->dev_sectors &&
3224 mddev->recovery_cp > mddev->dev_sectors) {
3225 mddev->recovery_cp = mddev->dev_sectors;
3226 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3227 }
3228 mddev->dev_sectors = sectors;
3229 mddev->resync_max_sectors = sectors;
3230 return 0;
3231}
3232
3233static int raid1_reshape(struct mddev *mddev)
3234{
3235 /* We need to:
3236 * 1/ resize the r1bio_pool
3237 * 2/ resize conf->mirrors
3238 *
3239 * We allocate a new r1bio_pool if we can.
3240 * Then raise a device barrier and wait until all IO stops.
3241 * Then resize conf->mirrors and swap in the new r1bio pool.
3242 *
3243 * At the same time, we "pack" the devices so that all the missing
3244 * devices have the higher raid_disk numbers.
3245 */
3246 mempool_t newpool, oldpool;
3247 struct pool_info *newpoolinfo;
3248 struct raid1_info *newmirrors;
3249 struct r1conf *conf = mddev->private;
3250 int cnt, raid_disks;
3251 unsigned long flags;
3252 int d, d2;
3253 int ret;
3254
3255 memset(&newpool, 0, sizeof(newpool));
3256 memset(&oldpool, 0, sizeof(oldpool));
3257
3258 /* Cannot change chunk_size, layout, or level */
3259 if (mddev->chunk_sectors != mddev->new_chunk_sectors ||
3260 mddev->layout != mddev->new_layout ||
3261 mddev->level != mddev->new_level) {
3262 mddev->new_chunk_sectors = mddev->chunk_sectors;
3263 mddev->new_layout = mddev->layout;
3264 mddev->new_level = mddev->level;
3265 return -EINVAL;
3266 }
3267
3268 if (!mddev_is_clustered(mddev))
3269 md_allow_write(mddev);
3270
3271 raid_disks = mddev->raid_disks + mddev->delta_disks;
3272
3273 if (raid_disks < conf->raid_disks) {
3274 cnt=0;
3275 for (d= 0; d < conf->raid_disks; d++)
3276 if (conf->mirrors[d].rdev)
3277 cnt++;
3278 if (cnt > raid_disks)
3279 return -EBUSY;
3280 }
3281
3282 newpoolinfo = kmalloc(sizeof(*newpoolinfo), GFP_KERNEL);
3283 if (!newpoolinfo)
3284 return -ENOMEM;
3285 newpoolinfo->mddev = mddev;
3286 newpoolinfo->raid_disks = raid_disks * 2;
3287
3288 ret = mempool_init(&newpool, NR_RAID_BIOS, r1bio_pool_alloc,
3289 rbio_pool_free, newpoolinfo);
3290 if (ret) {
3291 kfree(newpoolinfo);
3292 return ret;
3293 }
3294 newmirrors = kzalloc(array3_size(sizeof(struct raid1_info),
3295 raid_disks, 2),
3296 GFP_KERNEL);
3297 if (!newmirrors) {
3298 kfree(newpoolinfo);
3299 mempool_exit(&newpool);
3300 return -ENOMEM;
3301 }
3302
3303 freeze_array(conf, 0);
3304
3305 /* ok, everything is stopped */
3306 oldpool = conf->r1bio_pool;
3307 conf->r1bio_pool = newpool;
3308
3309 for (d = d2 = 0; d < conf->raid_disks; d++) {
3310 struct md_rdev *rdev = conf->mirrors[d].rdev;
3311 if (rdev && rdev->raid_disk != d2) {
3312 sysfs_unlink_rdev(mddev, rdev);
3313 rdev->raid_disk = d2;
3314 sysfs_unlink_rdev(mddev, rdev);
3315 if (sysfs_link_rdev(mddev, rdev))
3316 pr_warn("md/raid1:%s: cannot register rd%d\n",
3317 mdname(mddev), rdev->raid_disk);
3318 }
3319 if (rdev)
3320 newmirrors[d2++].rdev = rdev;
3321 }
3322 kfree(conf->mirrors);
3323 conf->mirrors = newmirrors;
3324 kfree(conf->poolinfo);
3325 conf->poolinfo = newpoolinfo;
3326
3327 spin_lock_irqsave(&conf->device_lock, flags);
3328 mddev->degraded += (raid_disks - conf->raid_disks);
3329 spin_unlock_irqrestore(&conf->device_lock, flags);
3330 conf->raid_disks = mddev->raid_disks = raid_disks;
3331 mddev->delta_disks = 0;
3332
3333 unfreeze_array(conf);
3334
3335 set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
3336 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3337 md_wakeup_thread(mddev->thread);
3338
3339 mempool_exit(&oldpool);
3340 return 0;
3341}
3342
3343static void raid1_quiesce(struct mddev *mddev, int quiesce)
3344{
3345 struct r1conf *conf = mddev->private;
3346
3347 if (quiesce)
3348 freeze_array(conf, 0);
3349 else
3350 unfreeze_array(conf);
3351}
3352
3353static void *raid1_takeover(struct mddev *mddev)
3354{
3355 /* raid1 can take over:
3356 * raid5 with 2 devices, any layout or chunk size
3357 */
3358 if (mddev->level == 5 && mddev->raid_disks == 2) {
3359 struct r1conf *conf;
3360 mddev->new_level = 1;
3361 mddev->new_layout = 0;
3362 mddev->new_chunk_sectors = 0;
3363 conf = setup_conf(mddev);
3364 if (!IS_ERR(conf)) {
3365 /* Array must appear to be quiesced */
3366 conf->array_frozen = 1;
3367 mddev_clear_unsupported_flags(mddev,
3368 UNSUPPORTED_MDDEV_FLAGS);
3369 }
3370 return conf;
3371 }
3372 return ERR_PTR(-EINVAL);
3373}
3374
3375static struct md_personality raid1_personality =
3376{
3377 .name = "raid1",
3378 .level = 1,
3379 .owner = THIS_MODULE,
3380 .make_request = raid1_make_request,
3381 .run = raid1_run,
3382 .free = raid1_free,
3383 .status = raid1_status,
3384 .error_handler = raid1_error,
3385 .hot_add_disk = raid1_add_disk,
3386 .hot_remove_disk= raid1_remove_disk,
3387 .spare_active = raid1_spare_active,
3388 .sync_request = raid1_sync_request,
3389 .resize = raid1_resize,
3390 .size = raid1_size,
3391 .check_reshape = raid1_reshape,
3392 .quiesce = raid1_quiesce,
3393 .takeover = raid1_takeover,
3394};
3395
3396static int __init raid_init(void)
3397{
3398 return register_md_personality(&raid1_personality);
3399}
3400
3401static void raid_exit(void)
3402{
3403 unregister_md_personality(&raid1_personality);
3404}
3405
3406module_init(raid_init);
3407module_exit(raid_exit);
3408MODULE_LICENSE("GPL");
3409MODULE_DESCRIPTION("RAID1 (mirroring) personality for MD");
3410MODULE_ALIAS("md-personality-3"); /* RAID1 */
3411MODULE_ALIAS("md-raid1");
3412MODULE_ALIAS("md-level-1");
3413
3414module_param(max_queued_requests, int, S_IRUGO|S_IWUSR);