1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * raid1.c : Multiple Devices driver for Linux
5 * Copyright (C) 1999, 2000, 2001 Ingo Molnar, Red Hat
7 * Copyright (C) 1996, 1997, 1998 Ingo Molnar, Miguel de Icaza, Gadi Oxman
9 * RAID-1 management functions.
11 * Better read-balancing code written by Mika Kuoppala <miku@iki.fi>, 2000
13 * Fixes to reconstruction by Jakob Østergaard" <jakob@ostenfeld.dk>
14 * Various fixes by Neil Brown <neilb@cse.unsw.edu.au>
16 * Changes by Peter T. Breuer <ptb@it.uc3m.es> 31/1/2003 to support
17 * bitmapped intelligence in resync:
19 * - bitmap marked during normal i/o
20 * - bitmap used to skip nondirty blocks during sync
22 * Additions to bitmap code, (C) 2003-2004 Paul Clements, SteelEye Technology:
23 * - persistent bitmap code
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>
33 #include <trace/events/block.h>
37 #include "md-bitmap.h"
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))
45 static void allow_barrier(struct r1conf *conf, sector_t sector_nr);
46 static void lower_barrier(struct r1conf *conf, sector_t sector_nr);
48 #define raid1_log(md, fmt, args...) \
49 do { if ((md)->queue) blk_add_trace_msg((md)->queue, "raid1 " fmt, ##args); } while (0)
53 static int check_and_add_wb(struct md_rdev *rdev, sector_t lo, sector_t hi)
55 struct wb_info *wi, *temp_wi;
58 struct mddev *mddev = rdev->mddev;
60 wi = mempool_alloc(mddev->wb_info_pool, GFP_NOIO);
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) {
74 list_add(&wi->list, &rdev->wb_list);
76 mempool_free(wi, mddev->wb_info_pool);
77 spin_unlock_irqrestore(&rdev->wb_list_lock, flags);
82 static void remove_wb(struct md_rdev *rdev, sector_t lo, sector_t hi)
87 struct mddev *mddev = rdev->mddev;
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) {
93 mempool_free(wi, mddev->wb_info_pool);
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);
105 * for resync bio, r1bio pointer can be retrieved from the per-bio
106 * 'struct resync_pages'.
108 static inline struct r1bio *get_resync_r1bio(struct bio *bio)
110 return get_resync_pages(bio)->raid_bio;
113 static void * r1bio_pool_alloc(gfp_t gfp_flags, void *data)
115 struct pool_info *pi = data;
116 int size = offsetof(struct r1bio, bios[pi->raid_disks]);
118 /* allocate a r1bio with room for raid_disks entries in the bios array */
119 return kzalloc(size, gfp_flags);
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)
129 static void * r1buf_pool_alloc(gfp_t gfp_flags, void *data)
131 struct pool_info *pi = data;
132 struct r1bio *r1_bio;
136 struct resync_pages *rps;
138 r1_bio = r1bio_pool_alloc(gfp_flags, pi);
142 rps = kmalloc_array(pi->raid_disks, sizeof(struct resync_pages),
148 * Allocate bios : 1 for reading, n-1 for writing
150 for (j = pi->raid_disks ; j-- ; ) {
151 bio = bio_kmalloc(gfp_flags, RESYNC_PAGES);
154 r1_bio->bios[j] = bio;
157 * Allocate RESYNC_PAGES data pages and attach them to
159 * If this is a user-requested check/repair, allocate
160 * RESYNC_PAGES for each bio.
162 if (test_bit(MD_RECOVERY_REQUESTED, &pi->mddev->recovery))
163 need_pages = pi->raid_disks;
166 for (j = 0; j < pi->raid_disks; j++) {
167 struct resync_pages *rp = &rps[j];
169 bio = r1_bio->bios[j];
171 if (j < need_pages) {
172 if (resync_alloc_pages(rp, gfp_flags))
175 memcpy(rp, &rps[0], sizeof(*rp));
176 resync_get_all_pages(rp);
179 rp->raid_bio = r1_bio;
180 bio->bi_private = rp;
183 r1_bio->master_bio = NULL;
189 resync_free_pages(&rps[j]);
192 while (++j < pi->raid_disks)
193 bio_put(r1_bio->bios[j]);
197 rbio_pool_free(r1_bio, data);
201 static void r1buf_pool_free(void *__r1_bio, void *data)
203 struct pool_info *pi = data;
205 struct r1bio *r1bio = __r1_bio;
206 struct resync_pages *rp = NULL;
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]);
214 /* resync pages array stored in the 1st bio's .bi_private */
217 rbio_pool_free(r1bio, data);
220 static void put_all_bios(struct r1conf *conf, struct r1bio *r1_bio)
224 for (i = 0; i < conf->raid_disks * 2; i++) {
225 struct bio **bio = r1_bio->bios + i;
226 if (!BIO_SPECIAL(*bio))
232 static void free_r1bio(struct r1bio *r1_bio)
234 struct r1conf *conf = r1_bio->mddev->private;
236 put_all_bios(conf, r1_bio);
237 mempool_free(r1_bio, &conf->r1bio_pool);
240 static void put_buf(struct r1bio *r1_bio)
242 struct r1conf *conf = r1_bio->mddev->private;
243 sector_t sect = r1_bio->sector;
246 for (i = 0; i < conf->raid_disks * 2; i++) {
247 struct bio *bio = r1_bio->bios[i];
249 rdev_dec_pending(conf->mirrors[i].rdev, r1_bio->mddev);
252 mempool_free(r1_bio, &conf->r1buf_pool);
254 lower_barrier(conf, sect);
257 static void reschedule_retry(struct r1bio *r1_bio)
260 struct mddev *mddev = r1_bio->mddev;
261 struct r1conf *conf = mddev->private;
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);
270 wake_up(&conf->wait_barrier);
271 md_wakeup_thread(mddev->thread);
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
279 static void call_bio_endio(struct r1bio *r1_bio)
281 struct bio *bio = r1_bio->master_bio;
282 struct r1conf *conf = r1_bio->mddev->private;
284 if (!test_bit(R1BIO_Uptodate, &r1_bio->state))
285 bio->bi_status = BLK_STS_IOERR;
289 * Wake up any possible resync thread that waits for the device
292 allow_barrier(conf, r1_bio->sector);
295 static void raid_end_bio_io(struct r1bio *r1_bio)
297 struct bio *bio = r1_bio->master_bio;
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);
306 call_bio_endio(r1_bio);
312 * Update disk head position estimator based on IRQ completion info.
314 static inline void update_head_pos(int disk, struct r1bio *r1_bio)
316 struct r1conf *conf = r1_bio->mddev->private;
318 conf->mirrors[disk].head_position =
319 r1_bio->sector + (r1_bio->sectors);
323 * Find the disk number which triggered given bio
325 static int find_bio_disk(struct r1bio *r1_bio, struct bio *bio)
328 struct r1conf *conf = r1_bio->mddev->private;
329 int raid_disks = conf->raid_disks;
331 for (mirror = 0; mirror < raid_disks * 2; mirror++)
332 if (r1_bio->bios[mirror] == bio)
335 BUG_ON(mirror == raid_disks * 2);
336 update_head_pos(mirror, r1_bio);
341 static void raid1_end_read_request(struct bio *bio)
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;
349 * this branch is our 'one mirror IO has finished' event handler:
351 update_head_pos(r1_bio->read_disk, r1_bio);
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
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"
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)))
371 spin_unlock_irqrestore(&conf->device_lock, flags);
375 raid_end_bio_io(r1_bio);
376 rdev_dec_pending(rdev, conf->mddev);
381 char b[BDEVNAME_SIZE];
382 pr_err_ratelimited("md/raid1:%s: %s: rescheduling sector %llu\n",
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 */
392 static void close_write(struct r1bio *r1_bio)
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;
400 /* clear the bitmap if all writes complete successfully */
401 md_bitmap_endwrite(r1_bio->mddev->bitmap, r1_bio->sector,
403 !test_bit(R1BIO_Degraded, &r1_bio->state),
404 test_bit(R1BIO_BehindIO, &r1_bio->state));
405 md_write_end(r1_bio->mddev);
408 static void r1_bio_write_done(struct r1bio *r1_bio)
410 if (!atomic_dec_and_test(&r1_bio->remaining))
413 if (test_bit(R1BIO_WriteError, &r1_bio->state))
414 reschedule_retry(r1_bio);
417 if (test_bit(R1BIO_MadeGood, &r1_bio->state))
418 reschedule_retry(r1_bio);
420 raid_end_bio_io(r1_bio);
424 static void raid1_end_write_request(struct bio *bio)
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;
434 discard_error = bio->bi_status && bio_op(bio) == REQ_OP_DISCARD;
437 * 'one mirror IO has finished' event handler:
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);
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);
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.
458 if (!test_bit(Faulty, &rdev->flags))
459 set_bit(R1BIO_WriteError, &r1_bio->state);
461 /* Finished with this branch */
462 r1_bio->bios[mirror] = NULL;
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
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.
479 r1_bio->bios[mirror] = NULL;
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
489 if (test_bit(In_sync, &rdev->flags) &&
490 !test_bit(Faulty, &rdev->flags))
491 set_bit(R1BIO_Uptodate, &r1_bio->state);
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);
502 if (test_bit(WBCollisionCheck, &rdev->flags)) {
503 sector_t lo = r1_bio->sector;
504 sector_t hi = r1_bio->sector + r1_bio->sectors;
506 remove_wb(rdev, lo, hi);
508 if (test_bit(WriteMostly, &rdev->flags))
509 atomic_dec(&r1_bio->behind_remaining);
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
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"
525 (unsigned long long) mbio->bi_iter.bi_sector,
526 (unsigned long long) bio_end_sector(mbio) - 1);
527 call_bio_endio(r1_bio);
531 if (r1_bio->bios[mirror] == NULL)
532 rdev_dec_pending(rdev, conf->mddev);
535 * Let's see if all mirrored write operations have finished
538 r1_bio_write_done(r1_bio);
544 static sector_t align_to_barrier_unit_end(sector_t start_sector,
549 WARN_ON(sectors == 0);
551 * len is the number of sectors from start_sector to end of the
552 * barrier unit which start_sector belongs to.
554 len = round_up(start_sector + 1, BARRIER_UNIT_SECTOR_SIZE) -
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.
572 * If there are 2 mirrors in the same 2 devices, performance degrades
573 * because position is mirror, not device based.
575 * The rdev for the device selected will have nr_pending incremented.
577 static int read_balance(struct r1conf *conf, struct r1bio *r1_bio, int *max_sectors)
579 const sector_t this_sector = r1_bio->sector;
581 int best_good_sectors;
582 int best_disk, best_dist_disk, best_pending_disk;
586 unsigned int min_pending;
587 struct md_rdev *rdev;
589 int choose_next_idle;
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.
598 sectors = r1_bio->sectors;
601 best_dist = MaxSector;
602 best_pending_disk = -1;
603 min_pending = UINT_MAX;
604 best_good_sectors = 0;
606 choose_next_idle = 0;
607 clear_bit(R1BIO_FailFast, &r1_bio->state);
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)))
617 for (disk = 0 ; disk < conf->raid_disks * 2 ; disk++) {
621 unsigned int pending;
624 rdev = rcu_dereference(conf->mirrors[disk].rdev);
625 if (r1_bio->bios[disk] == IO_BLOCKED
627 || test_bit(Faulty, &rdev->flags))
629 if (!test_bit(In_sync, &rdev->flags) &&
630 rdev->recovery_offset < this_sector + sectors)
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 */
641 best_good_sectors = first_bad - this_sector;
643 best_good_sectors = sectors;
644 best_dist_disk = disk;
645 best_pending_disk = disk;
649 /* This is a reasonable device to use. It might
652 if (is_badblock(rdev, this_sector, sectors,
653 &first_bad, &bad_sectors)) {
654 if (best_dist < MaxSector)
655 /* already have a better device */
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..
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;
669 sector_t good_sectors = first_bad - this_sector;
670 if (good_sectors > best_good_sectors) {
671 best_good_sectors = good_sectors;
679 if ((sectors > best_good_sectors) && (best_disk >= 0))
681 best_good_sectors = sectors;
685 /* At least two disks to choose from so failfast is OK */
686 set_bit(R1BIO_FailFast, &r1_bio->state);
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);
696 /* Don't change to another disk for sequential reads */
697 if (conf->mirrors[disk].next_seq_sect == this_sector
699 int opt_iosize = bdev_io_opt(rdev->bdev) >> 9;
700 struct raid1_info *mirror = &conf->mirrors[disk];
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.
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 >=
721 choose_next_idle = 1;
727 if (choose_next_idle)
730 if (min_pending > pending) {
731 min_pending = pending;
732 best_pending_disk = disk;
735 if (dist < best_dist) {
737 best_dist_disk = disk;
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.
747 if (best_disk == -1) {
748 if (has_nonrot_disk || min_pending == 0)
749 best_disk = best_pending_disk;
751 best_disk = best_dist_disk;
754 if (best_disk >= 0) {
755 rdev = rcu_dereference(conf->mirrors[best_disk].rdev);
758 atomic_inc(&rdev->nr_pending);
759 sectors = best_good_sectors;
761 if (conf->mirrors[best_disk].next_seq_sect != this_sector)
762 conf->mirrors[best_disk].seq_start = this_sector;
764 conf->mirrors[best_disk].next_seq_sect = this_sector + sectors;
767 *max_sectors = sectors;
772 static int raid1_congested(struct mddev *mddev, int bits)
774 struct r1conf *conf = mddev->private;
777 if ((bits & (1 << WB_async_congested)) &&
778 conf->pending_count >= max_queued_requests)
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);
789 /* Note the '|| 1' - when read_balance prefers
790 * non-congested targets, it can be removed
792 if ((bits & (1 << WB_async_congested)) || 1)
793 ret |= bdi_congested(q->backing_dev_info, bits);
795 ret &= bdi_congested(q->backing_dev_info, bits);
802 static void flush_bio_list(struct r1conf *conf, struct bio *bio)
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);
808 while (bio) { /* submit pending writes */
809 struct bio *next = bio->bi_next;
810 struct md_rdev *rdev = (void *)bio->bi_disk;
812 bio_set_dev(bio, rdev->bdev);
813 if (test_bit(Faulty, &rdev->flags)) {
815 } else if (unlikely((bio_op(bio) == REQ_OP_DISCARD) &&
816 !blk_queue_discard(bio->bi_disk->queue)))
820 generic_make_request(bio);
825 static void flush_pending_writes(struct r1conf *conf)
827 /* Any writes that have been queued but are awaiting
828 * bitmap updates get flushed here.
830 spin_lock_irq(&conf->device_lock);
832 if (conf->pending_bio_list.head) {
833 struct blk_plug plug;
836 bio = bio_list_get(&conf->pending_bio_list);
837 conf->pending_count = 0;
838 spin_unlock_irq(&conf->device_lock);
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
849 __set_current_state(TASK_RUNNING);
850 blk_start_plug(&plug);
851 flush_bio_list(conf, bio);
852 blk_finish_plug(&plug);
854 spin_unlock_irq(&conf->device_lock);
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
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.
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.
878 * If resync/recovery is interrupted, returns -EINTR;
879 * Otherwise, returns 0.
881 static int raise_barrier(struct r1conf *conf, sector_t sector_nr)
883 int idx = sector_to_idx(sector_nr);
885 spin_lock_irq(&conf->resync_lock);
887 /* Wait until no block IO is waiting */
888 wait_event_lock_irq(conf->wait_barrier,
889 !atomic_read(&conf->nr_waiting[idx]),
892 /* block any new IO from starting */
893 atomic_inc(&conf->barrier[idx]);
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().
902 smp_mb__after_atomic();
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.
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),
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);
925 atomic_inc(&conf->nr_sync_pending);
926 spin_unlock_irq(&conf->resync_lock);
931 static void lower_barrier(struct r1conf *conf, sector_t sector_nr)
933 int idx = sector_to_idx(sector_nr);
935 BUG_ON(atomic_read(&conf->barrier[idx]) <= 0);
937 atomic_dec(&conf->barrier[idx]);
938 atomic_dec(&conf->nr_sync_pending);
939 wake_up(&conf->wait_barrier);
942 static void _wait_barrier(struct r1conf *conf, int idx)
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.
952 atomic_inc(&conf->nr_pending[idx]);
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().
961 smp_mb__after_atomic();
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
972 if (!READ_ONCE(conf->array_frozen) &&
973 !atomic_read(&conf->barrier[idx]))
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.
983 spin_lock_irq(&conf->resync_lock);
984 atomic_inc(&conf->nr_waiting[idx]);
985 atomic_dec(&conf->nr_pending[idx]);
987 * In case freeze_array() is waiting for
988 * get_unqueued_pending() == extra
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]),
996 atomic_inc(&conf->nr_pending[idx]);
997 atomic_dec(&conf->nr_waiting[idx]);
998 spin_unlock_irq(&conf->resync_lock);
1001 static void wait_read_barrier(struct r1conf *conf, sector_t sector_nr)
1003 int idx = sector_to_idx(sector_nr);
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.
1012 atomic_inc(&conf->nr_pending[idx]);
1014 if (!READ_ONCE(conf->array_frozen))
1017 spin_lock_irq(&conf->resync_lock);
1018 atomic_inc(&conf->nr_waiting[idx]);
1019 atomic_dec(&conf->nr_pending[idx]);
1021 * In case freeze_array() is waiting for
1022 * get_unqueued_pending() == extra
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,
1029 atomic_inc(&conf->nr_pending[idx]);
1030 atomic_dec(&conf->nr_waiting[idx]);
1031 spin_unlock_irq(&conf->resync_lock);
1034 static void wait_barrier(struct r1conf *conf, sector_t sector_nr)
1036 int idx = sector_to_idx(sector_nr);
1038 _wait_barrier(conf, idx);
1041 static void _allow_barrier(struct r1conf *conf, int idx)
1043 atomic_dec(&conf->nr_pending[idx]);
1044 wake_up(&conf->wait_barrier);
1047 static void allow_barrier(struct r1conf *conf, sector_t sector_nr)
1049 int idx = sector_to_idx(sector_nr);
1051 _allow_barrier(conf, idx);
1054 /* conf->resync_lock should be held */
1055 static int get_unqueued_pending(struct r1conf *conf)
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]);
1067 static void freeze_array(struct r1conf *conf, int extra)
1069 /* Stop sync I/O and normal I/O and wait for everything to
1071 * This is called in two situations:
1072 * 1) management command handlers (reshape, remove disk, quiesce).
1073 * 2) one normal I/O request failed.
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.
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.
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.
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(
1097 get_unqueued_pending(conf) == extra,
1099 flush_pending_writes(conf));
1100 spin_unlock_irq(&conf->resync_lock);
1102 static void unfreeze_array(struct r1conf *conf)
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);
1111 static void alloc_behind_master_bio(struct r1bio *r1_bio,
1114 int size = bio->bi_iter.bi_size;
1115 unsigned vcnt = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
1117 struct bio *behind_bio = NULL;
1119 behind_bio = bio_alloc_mddev(GFP_NOIO, vcnt, r1_bio->mddev);
1123 /* discard op, we don't support writezero/writesame yet */
1124 if (!bio_has_data(bio)) {
1125 behind_bio->bi_iter.bi_size = size;
1129 behind_bio->bi_write_hint = bio->bi_write_hint;
1131 while (i < vcnt && size) {
1133 int len = min_t(int, PAGE_SIZE, size);
1135 page = alloc_page(GFP_NOIO);
1136 if (unlikely(!page))
1139 bio_add_page(behind_bio, page, len, 0);
1145 bio_copy_data(behind_bio, bio);
1147 r1_bio->behind_master_bio = behind_bio;
1148 set_bit(R1BIO_BehindIO, &r1_bio->state);
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);
1159 struct raid1_plug_cb {
1160 struct blk_plug_cb cb;
1161 struct bio_list pending;
1165 static void raid1_unplug(struct blk_plug_cb *cb, bool from_schedule)
1167 struct raid1_plug_cb *plug = container_of(cb, struct raid1_plug_cb,
1169 struct mddev *mddev = plug->cb.data;
1170 struct r1conf *conf = mddev->private;
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);
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);
1190 static void init_r1bio(struct r1bio *r1_bio, struct mddev *mddev, struct bio *bio)
1192 r1_bio->master_bio = bio;
1193 r1_bio->sectors = bio_sectors(bio);
1195 r1_bio->mddev = mddev;
1196 r1_bio->sector = bio->bi_iter.bi_sector;
1199 static inline struct r1bio *
1200 alloc_r1bio(struct mddev *mddev, struct bio *bio)
1202 struct r1conf *conf = mddev->private;
1203 struct r1bio *r1_bio;
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);
1212 static void raid1_read_request(struct mddev *mddev, struct bio *bio,
1213 int max_read_sectors, struct r1bio *r1_bio)
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);
1223 bool print_msg = !!r1_bio;
1224 char b[BDEVNAME_SIZE];
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.
1231 gfp_t gfp = r1_bio ? (GFP_NOIO | __GFP_HIGH) : GFP_NOIO;
1234 /* Need to get the block device name carefully */
1235 struct md_rdev *rdev;
1237 rdev = rcu_dereference(conf->mirrors[r1_bio->read_disk].rdev);
1239 bdevname(rdev->bdev, b);
1246 * Still need barrier for READ in case that whole
1249 wait_read_barrier(conf, bio->bi_iter.bi_sector);
1252 r1_bio = alloc_r1bio(mddev, bio);
1254 init_r1bio(r1_bio, mddev, bio);
1255 r1_bio->sectors = max_read_sectors;
1258 * make_request() can abort the operation when read-ahead is being
1259 * used and no empty request is available.
1261 rdisk = read_balance(conf, r1_bio, &max_sectors);
1264 /* couldn't find anywhere to read from */
1266 pr_crit_ratelimited("md/raid1:%s: %s: unrecoverable I/O read error for block %llu\n",
1269 (unsigned long long)r1_bio->sector);
1271 raid_end_bio_io(r1_bio);
1274 mirror = conf->mirrors + rdisk;
1277 pr_info_ratelimited("md/raid1:%s: redirecting sector %llu to other mirror: %s\n",
1279 (unsigned long long)r1_bio->sector,
1280 bdevname(mirror->rdev->bdev, b));
1282 if (test_bit(WriteMostly, &mirror->rdev->flags) &&
1285 * Reading from a write-mostly device must take care not to
1286 * over-take any writes that are 'behind'
1288 raid1_log(mddev, "wait behind writes");
1289 wait_event(bitmap->behind_wait,
1290 atomic_read(&bitmap->behind_writes) == 0);
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);
1299 r1_bio->master_bio = bio;
1300 r1_bio->sectors = max_sectors;
1303 r1_bio->read_disk = rdisk;
1305 read_bio = bio_clone_fast(bio, gfp, &mddev->bio_set);
1307 r1_bio->bios[rdisk] = read_bio;
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;
1320 trace_block_bio_remap(read_bio->bi_disk->queue, read_bio,
1321 disk_devt(mddev->gendisk), r1_bio->sector);
1323 generic_make_request(read_bio);
1326 static void raid1_write_request(struct mddev *mddev, struct bio *bio,
1327 int max_write_sectors)
1329 struct r1conf *conf = mddev->private;
1330 struct r1bio *r1_bio;
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;
1340 if (mddev_is_clustered(mddev) &&
1341 md_cluster_ops->area_resyncing(mddev, WRITE,
1342 bio->bi_iter.bi_sector, bio_end_sector(bio))) {
1346 prepare_to_wait(&conf->wait_barrier,
1348 if (!md_cluster_ops->area_resyncing(mddev, WRITE,
1349 bio->bi_iter.bi_sector,
1350 bio_end_sector(bio)))
1354 finish_wait(&conf->wait_barrier, &w);
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.
1362 wait_barrier(conf, bio->bi_iter.bi_sector);
1364 r1_bio = alloc_r1bio(mddev, bio);
1365 r1_bio->sectors = max_write_sectors;
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);
1373 /* first select target devices under rcu_lock and
1374 * inc refcount on their rdev. Record them by setting
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
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.
1384 disks = conf->raid_disks * 2;
1386 blocked_rdev = NULL;
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;
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);
1403 atomic_inc(&rdev->nr_pending);
1404 if (test_bit(WriteErrorSeen, &rdev->flags)) {
1409 is_bad = is_badblock(rdev, r1_bio->sector, max_sectors,
1410 &first_bad, &bad_sectors);
1412 /* mustn't write here until the bad block is
1414 set_bit(BlockedBadBlocks, &rdev->flags);
1415 blocked_rdev = rdev;
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
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
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
1440 int good_sectors = first_bad - r1_bio->sector;
1441 if (good_sectors < max_sectors)
1442 max_sectors = good_sectors;
1445 r1_bio->bios[i] = bio;
1449 if (unlikely(blocked_rdev)) {
1450 /* Wait for this device to become unblocked */
1453 for (j = 0; j < i; j++)
1454 if (r1_bio->bios[j])
1455 rdev_dec_pending(conf->mirrors[j].rdev, mddev);
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);
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);
1470 r1_bio->master_bio = bio;
1471 r1_bio->sectors = max_sectors;
1474 atomic_set(&r1_bio->remaining, 1);
1475 atomic_set(&r1_bio->behind_remaining, 0);
1479 for (i = 0; i < disks; i++) {
1480 struct bio *mbio = NULL;
1481 if (!r1_bio->bios[i])
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 */
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);
1496 md_bitmap_startwrite(bitmap, r1_bio->sector, r1_bio->sectors,
1497 test_bit(R1BIO_BehindIO, &r1_bio->state));
1501 if (r1_bio->behind_master_bio)
1502 mbio = bio_clone_fast(r1_bio->behind_master_bio,
1503 GFP_NOIO, &mddev->bio_set);
1505 mbio = bio_clone_fast(bio, GFP_NOIO, &mddev->bio_set);
1507 if (r1_bio->behind_master_bio) {
1508 struct md_rdev *rdev = conf->mirrors[i].rdev;
1510 if (test_bit(WBCollisionCheck, &rdev->flags)) {
1511 sector_t lo = r1_bio->sector;
1512 sector_t hi = r1_bio->sector + r1_bio->sectors;
1514 wait_event(rdev->wb_io_wait,
1515 check_and_add_wb(rdev, lo, hi) == 0);
1517 if (test_bit(WriteMostly, &rdev->flags))
1518 atomic_inc(&r1_bio->behind_remaining);
1521 r1_bio->bios[i] = mbio;
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;
1534 atomic_inc(&r1_bio->remaining);
1537 trace_block_bio_remap(mbio->bi_disk->queue,
1538 mbio, disk_devt(mddev->gendisk),
1540 /* flush_pending_writes() needs access to the rdev so...*/
1541 mbio->bi_disk = (void *)conf->mirrors[i].rdev;
1543 cb = blk_check_plugged(raid1_unplug, mddev, sizeof(*plug));
1545 plug = container_of(cb, struct raid1_plug_cb, cb);
1549 bio_list_add(&plug->pending, mbio);
1550 plug->pending_cnt++;
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);
1560 r1_bio_write_done(r1_bio);
1562 /* In case raid1d snuck in to freeze_array */
1563 wake_up(&conf->wait_barrier);
1566 static bool raid1_make_request(struct mddev *mddev, struct bio *bio)
1570 if (unlikely(bio->bi_opf & REQ_PREFLUSH)
1571 && md_flush_request(mddev, bio))
1575 * There is a limit to the maximum size, but
1576 * the read/write handler might find a lower limit
1577 * due to bad blocks. To avoid multiple splits,
1578 * we pass the maximum number of sectors down
1579 * and let the lower level perform the split.
1581 sectors = align_to_barrier_unit_end(
1582 bio->bi_iter.bi_sector, bio_sectors(bio));
1584 if (bio_data_dir(bio) == READ)
1585 raid1_read_request(mddev, bio, sectors, NULL);
1587 if (!md_write_start(mddev,bio))
1589 raid1_write_request(mddev, bio, sectors);
1594 static void raid1_status(struct seq_file *seq, struct mddev *mddev)
1596 struct r1conf *conf = mddev->private;
1599 seq_printf(seq, " [%d/%d] [", conf->raid_disks,
1600 conf->raid_disks - mddev->degraded);
1602 for (i = 0; i < conf->raid_disks; i++) {
1603 struct md_rdev *rdev = rcu_dereference(conf->mirrors[i].rdev);
1604 seq_printf(seq, "%s",
1605 rdev && test_bit(In_sync, &rdev->flags) ? "U" : "_");
1608 seq_printf(seq, "]");
1611 static void raid1_error(struct mddev *mddev, struct md_rdev *rdev)
1613 char b[BDEVNAME_SIZE];
1614 struct r1conf *conf = mddev->private;
1615 unsigned long flags;
1618 * If it is not operational, then we have already marked it as dead
1619 * else if it is the last working disks with "fail_last_dev == false",
1620 * ignore the error, let the next level up know.
1621 * else mark the drive as failed
1623 spin_lock_irqsave(&conf->device_lock, flags);
1624 if (test_bit(In_sync, &rdev->flags) && !mddev->fail_last_dev
1625 && (conf->raid_disks - mddev->degraded) == 1) {
1627 * Don't fail the drive, act as though we were just a
1628 * normal single drive.
1629 * However don't try a recovery from this drive as
1630 * it is very likely to fail.
1632 conf->recovery_disabled = mddev->recovery_disabled;
1633 spin_unlock_irqrestore(&conf->device_lock, flags);
1636 set_bit(Blocked, &rdev->flags);
1637 if (test_and_clear_bit(In_sync, &rdev->flags))
1639 set_bit(Faulty, &rdev->flags);
1640 spin_unlock_irqrestore(&conf->device_lock, flags);
1642 * if recovery is running, make sure it aborts.
1644 set_bit(MD_RECOVERY_INTR, &mddev->recovery);
1645 set_mask_bits(&mddev->sb_flags, 0,
1646 BIT(MD_SB_CHANGE_DEVS) | BIT(MD_SB_CHANGE_PENDING));
1647 pr_crit("md/raid1:%s: Disk failure on %s, disabling device.\n"
1648 "md/raid1:%s: Operation continuing on %d devices.\n",
1649 mdname(mddev), bdevname(rdev->bdev, b),
1650 mdname(mddev), conf->raid_disks - mddev->degraded);
1653 static void print_conf(struct r1conf *conf)
1657 pr_debug("RAID1 conf printout:\n");
1659 pr_debug("(!conf)\n");
1662 pr_debug(" --- wd:%d rd:%d\n", conf->raid_disks - conf->mddev->degraded,
1666 for (i = 0; i < conf->raid_disks; i++) {
1667 char b[BDEVNAME_SIZE];
1668 struct md_rdev *rdev = rcu_dereference(conf->mirrors[i].rdev);
1670 pr_debug(" disk %d, wo:%d, o:%d, dev:%s\n",
1671 i, !test_bit(In_sync, &rdev->flags),
1672 !test_bit(Faulty, &rdev->flags),
1673 bdevname(rdev->bdev,b));
1678 static void close_sync(struct r1conf *conf)
1682 for (idx = 0; idx < BARRIER_BUCKETS_NR; idx++) {
1683 _wait_barrier(conf, idx);
1684 _allow_barrier(conf, idx);
1687 mempool_exit(&conf->r1buf_pool);
1690 static int raid1_spare_active(struct mddev *mddev)
1693 struct r1conf *conf = mddev->private;
1695 unsigned long flags;
1698 * Find all failed disks within the RAID1 configuration
1699 * and mark them readable.
1700 * Called under mddev lock, so rcu protection not needed.
1701 * device_lock used to avoid races with raid1_end_read_request
1702 * which expects 'In_sync' flags and ->degraded to be consistent.
1704 spin_lock_irqsave(&conf->device_lock, flags);
1705 for (i = 0; i < conf->raid_disks; i++) {
1706 struct md_rdev *rdev = conf->mirrors[i].rdev;
1707 struct md_rdev *repl = conf->mirrors[conf->raid_disks + i].rdev;
1709 && !test_bit(Candidate, &repl->flags)
1710 && repl->recovery_offset == MaxSector
1711 && !test_bit(Faulty, &repl->flags)
1712 && !test_and_set_bit(In_sync, &repl->flags)) {
1713 /* replacement has just become active */
1715 !test_and_clear_bit(In_sync, &rdev->flags))
1718 /* Replaced device not technically
1719 * faulty, but we need to be sure
1720 * it gets removed and never re-added
1722 set_bit(Faulty, &rdev->flags);
1723 sysfs_notify_dirent_safe(
1728 && rdev->recovery_offset == MaxSector
1729 && !test_bit(Faulty, &rdev->flags)
1730 && !test_and_set_bit(In_sync, &rdev->flags)) {
1732 sysfs_notify_dirent_safe(rdev->sysfs_state);
1735 mddev->degraded -= count;
1736 spin_unlock_irqrestore(&conf->device_lock, flags);
1742 static int raid1_add_disk(struct mddev *mddev, struct md_rdev *rdev)
1744 struct r1conf *conf = mddev->private;
1747 struct raid1_info *p;
1749 int last = conf->raid_disks - 1;
1751 if (mddev->recovery_disabled == conf->recovery_disabled)
1754 if (md_integrity_add_rdev(rdev, mddev))
1757 if (rdev->raid_disk >= 0)
1758 first = last = rdev->raid_disk;
1761 * find the disk ... but prefer rdev->saved_raid_disk
1764 if (rdev->saved_raid_disk >= 0 &&
1765 rdev->saved_raid_disk >= first &&
1766 rdev->saved_raid_disk < conf->raid_disks &&
1767 conf->mirrors[rdev->saved_raid_disk].rdev == NULL)
1768 first = last = rdev->saved_raid_disk;
1770 for (mirror = first; mirror <= last; mirror++) {
1771 p = conf->mirrors + mirror;
1774 disk_stack_limits(mddev->gendisk, rdev->bdev,
1775 rdev->data_offset << 9);
1777 p->head_position = 0;
1778 rdev->raid_disk = mirror;
1780 /* As all devices are equivalent, we don't need a full recovery
1781 * if this was recently any drive of the array
1783 if (rdev->saved_raid_disk < 0)
1785 rcu_assign_pointer(p->rdev, rdev);
1788 if (test_bit(WantReplacement, &p->rdev->flags) &&
1789 p[conf->raid_disks].rdev == NULL) {
1790 /* Add this device as a replacement */
1791 clear_bit(In_sync, &rdev->flags);
1792 set_bit(Replacement, &rdev->flags);
1793 rdev->raid_disk = mirror;
1796 rcu_assign_pointer(p[conf->raid_disks].rdev, rdev);
1800 if (mddev->queue && blk_queue_discard(bdev_get_queue(rdev->bdev)))
1801 blk_queue_flag_set(QUEUE_FLAG_DISCARD, mddev->queue);
1806 static int raid1_remove_disk(struct mddev *mddev, struct md_rdev *rdev)
1808 struct r1conf *conf = mddev->private;
1810 int number = rdev->raid_disk;
1811 struct raid1_info *p = conf->mirrors + number;
1813 if (rdev != p->rdev)
1814 p = conf->mirrors + conf->raid_disks + number;
1817 if (rdev == p->rdev) {
1818 if (test_bit(In_sync, &rdev->flags) ||
1819 atomic_read(&rdev->nr_pending)) {
1823 /* Only remove non-faulty devices if recovery
1826 if (!test_bit(Faulty, &rdev->flags) &&
1827 mddev->recovery_disabled != conf->recovery_disabled &&
1828 mddev->degraded < conf->raid_disks) {
1833 if (!test_bit(RemoveSynchronized, &rdev->flags)) {
1835 if (atomic_read(&rdev->nr_pending)) {
1836 /* lost the race, try later */
1842 if (conf->mirrors[conf->raid_disks + number].rdev) {
1843 /* We just removed a device that is being replaced.
1844 * Move down the replacement. We drain all IO before
1845 * doing this to avoid confusion.
1847 struct md_rdev *repl =
1848 conf->mirrors[conf->raid_disks + number].rdev;
1849 freeze_array(conf, 0);
1850 if (atomic_read(&repl->nr_pending)) {
1851 /* It means that some queued IO of retry_list
1852 * hold repl. Thus, we cannot set replacement
1853 * as NULL, avoiding rdev NULL pointer
1854 * dereference in sync_request_write and
1855 * handle_write_finished.
1858 unfreeze_array(conf);
1861 clear_bit(Replacement, &repl->flags);
1863 conf->mirrors[conf->raid_disks + number].rdev = NULL;
1864 unfreeze_array(conf);
1867 clear_bit(WantReplacement, &rdev->flags);
1868 err = md_integrity_register(mddev);
1876 static void end_sync_read(struct bio *bio)
1878 struct r1bio *r1_bio = get_resync_r1bio(bio);
1880 update_head_pos(r1_bio->read_disk, r1_bio);
1883 * we have read a block, now it needs to be re-written,
1884 * or re-read if the read failed.
1885 * We don't do much here, just schedule handling by raid1d
1887 if (!bio->bi_status)
1888 set_bit(R1BIO_Uptodate, &r1_bio->state);
1890 if (atomic_dec_and_test(&r1_bio->remaining))
1891 reschedule_retry(r1_bio);
1894 static void abort_sync_write(struct mddev *mddev, struct r1bio *r1_bio)
1896 sector_t sync_blocks = 0;
1897 sector_t s = r1_bio->sector;
1898 long sectors_to_go = r1_bio->sectors;
1900 /* make sure these bits don't get cleared. */
1902 md_bitmap_end_sync(mddev->bitmap, s, &sync_blocks, 1);
1904 sectors_to_go -= sync_blocks;
1905 } while (sectors_to_go > 0);
1908 static void put_sync_write_buf(struct r1bio *r1_bio, int uptodate)
1910 if (atomic_dec_and_test(&r1_bio->remaining)) {
1911 struct mddev *mddev = r1_bio->mddev;
1912 int s = r1_bio->sectors;
1914 if (test_bit(R1BIO_MadeGood, &r1_bio->state) ||
1915 test_bit(R1BIO_WriteError, &r1_bio->state))
1916 reschedule_retry(r1_bio);
1919 md_done_sync(mddev, s, uptodate);
1924 static void end_sync_write(struct bio *bio)
1926 int uptodate = !bio->bi_status;
1927 struct r1bio *r1_bio = get_resync_r1bio(bio);
1928 struct mddev *mddev = r1_bio->mddev;
1929 struct r1conf *conf = mddev->private;
1932 struct md_rdev *rdev = conf->mirrors[find_bio_disk(r1_bio, bio)].rdev;
1935 abort_sync_write(mddev, r1_bio);
1936 set_bit(WriteErrorSeen, &rdev->flags);
1937 if (!test_and_set_bit(WantReplacement, &rdev->flags))
1938 set_bit(MD_RECOVERY_NEEDED, &
1940 set_bit(R1BIO_WriteError, &r1_bio->state);
1941 } else if (is_badblock(rdev, r1_bio->sector, r1_bio->sectors,
1942 &first_bad, &bad_sectors) &&
1943 !is_badblock(conf->mirrors[r1_bio->read_disk].rdev,
1946 &first_bad, &bad_sectors)
1948 set_bit(R1BIO_MadeGood, &r1_bio->state);
1950 put_sync_write_buf(r1_bio, uptodate);
1953 static int r1_sync_page_io(struct md_rdev *rdev, sector_t sector,
1954 int sectors, struct page *page, int rw)
1956 if (sync_page_io(rdev, sector, sectors << 9, page, rw, 0, false))
1960 set_bit(WriteErrorSeen, &rdev->flags);
1961 if (!test_and_set_bit(WantReplacement,
1963 set_bit(MD_RECOVERY_NEEDED, &
1964 rdev->mddev->recovery);
1966 /* need to record an error - either for the block or the device */
1967 if (!rdev_set_badblocks(rdev, sector, sectors, 0))
1968 md_error(rdev->mddev, rdev);
1972 static int fix_sync_read_error(struct r1bio *r1_bio)
1974 /* Try some synchronous reads of other devices to get
1975 * good data, much like with normal read errors. Only
1976 * read into the pages we already have so we don't
1977 * need to re-issue the read request.
1978 * We don't need to freeze the array, because being in an
1979 * active sync request, there is no normal IO, and
1980 * no overlapping syncs.
1981 * We don't need to check is_badblock() again as we
1982 * made sure that anything with a bad block in range
1983 * will have bi_end_io clear.
1985 struct mddev *mddev = r1_bio->mddev;
1986 struct r1conf *conf = mddev->private;
1987 struct bio *bio = r1_bio->bios[r1_bio->read_disk];
1988 struct page **pages = get_resync_pages(bio)->pages;
1989 sector_t sect = r1_bio->sector;
1990 int sectors = r1_bio->sectors;
1992 struct md_rdev *rdev;
1994 rdev = conf->mirrors[r1_bio->read_disk].rdev;
1995 if (test_bit(FailFast, &rdev->flags)) {
1996 /* Don't try recovering from here - just fail it
1997 * ... unless it is the last working device of course */
1998 md_error(mddev, rdev);
1999 if (test_bit(Faulty, &rdev->flags))
2000 /* Don't try to read from here, but make sure
2001 * put_buf does it's thing
2003 bio->bi_end_io = end_sync_write;
2008 int d = r1_bio->read_disk;
2012 if (s > (PAGE_SIZE>>9))
2015 if (r1_bio->bios[d]->bi_end_io == end_sync_read) {
2016 /* No rcu protection needed here devices
2017 * can only be removed when no resync is
2018 * active, and resync is currently active
2020 rdev = conf->mirrors[d].rdev;
2021 if (sync_page_io(rdev, sect, s<<9,
2023 REQ_OP_READ, 0, false)) {
2029 if (d == conf->raid_disks * 2)
2031 } while (!success && d != r1_bio->read_disk);
2034 char b[BDEVNAME_SIZE];
2036 /* Cannot read from anywhere, this block is lost.
2037 * Record a bad block on each device. If that doesn't
2038 * work just disable and interrupt the recovery.
2039 * Don't fail devices as that won't really help.
2041 pr_crit_ratelimited("md/raid1:%s: %s: unrecoverable I/O read error for block %llu\n",
2042 mdname(mddev), bio_devname(bio, b),
2043 (unsigned long long)r1_bio->sector);
2044 for (d = 0; d < conf->raid_disks * 2; d++) {
2045 rdev = conf->mirrors[d].rdev;
2046 if (!rdev || test_bit(Faulty, &rdev->flags))
2048 if (!rdev_set_badblocks(rdev, sect, s, 0))
2052 conf->recovery_disabled =
2053 mddev->recovery_disabled;
2054 set_bit(MD_RECOVERY_INTR, &mddev->recovery);
2055 md_done_sync(mddev, r1_bio->sectors, 0);
2067 /* write it back and re-read */
2068 while (d != r1_bio->read_disk) {
2070 d = conf->raid_disks * 2;
2072 if (r1_bio->bios[d]->bi_end_io != end_sync_read)
2074 rdev = conf->mirrors[d].rdev;
2075 if (r1_sync_page_io(rdev, sect, s,
2078 r1_bio->bios[d]->bi_end_io = NULL;
2079 rdev_dec_pending(rdev, mddev);
2083 while (d != r1_bio->read_disk) {
2085 d = conf->raid_disks * 2;
2087 if (r1_bio->bios[d]->bi_end_io != end_sync_read)
2089 rdev = conf->mirrors[d].rdev;
2090 if (r1_sync_page_io(rdev, sect, s,
2093 atomic_add(s, &rdev->corrected_errors);
2099 set_bit(R1BIO_Uptodate, &r1_bio->state);
2104 static void process_checks(struct r1bio *r1_bio)
2106 /* We have read all readable devices. If we haven't
2107 * got the block, then there is no hope left.
2108 * If we have, then we want to do a comparison
2109 * and skip the write if everything is the same.
2110 * If any blocks failed to read, then we need to
2111 * attempt an over-write
2113 struct mddev *mddev = r1_bio->mddev;
2114 struct r1conf *conf = mddev->private;
2119 /* Fix variable parts of all bios */
2120 vcnt = (r1_bio->sectors + PAGE_SIZE / 512 - 1) >> (PAGE_SHIFT - 9);
2121 for (i = 0; i < conf->raid_disks * 2; i++) {
2122 blk_status_t status;
2123 struct bio *b = r1_bio->bios[i];
2124 struct resync_pages *rp = get_resync_pages(b);
2125 if (b->bi_end_io != end_sync_read)
2127 /* fixup the bio for reuse, but preserve errno */
2128 status = b->bi_status;
2130 b->bi_status = status;
2131 b->bi_iter.bi_sector = r1_bio->sector +
2132 conf->mirrors[i].rdev->data_offset;
2133 bio_set_dev(b, conf->mirrors[i].rdev->bdev);
2134 b->bi_end_io = end_sync_read;
2135 rp->raid_bio = r1_bio;
2138 /* initialize bvec table again */
2139 md_bio_reset_resync_pages(b, rp, r1_bio->sectors << 9);
2141 for (primary = 0; primary < conf->raid_disks * 2; primary++)
2142 if (r1_bio->bios[primary]->bi_end_io == end_sync_read &&
2143 !r1_bio->bios[primary]->bi_status) {
2144 r1_bio->bios[primary]->bi_end_io = NULL;
2145 rdev_dec_pending(conf->mirrors[primary].rdev, mddev);
2148 r1_bio->read_disk = primary;
2149 for (i = 0; i < conf->raid_disks * 2; i++) {
2151 struct bio *pbio = r1_bio->bios[primary];
2152 struct bio *sbio = r1_bio->bios[i];
2153 blk_status_t status = sbio->bi_status;
2154 struct page **ppages = get_resync_pages(pbio)->pages;
2155 struct page **spages = get_resync_pages(sbio)->pages;
2157 int page_len[RESYNC_PAGES] = { 0 };
2158 struct bvec_iter_all iter_all;
2160 if (sbio->bi_end_io != end_sync_read)
2162 /* Now we can 'fixup' the error value */
2163 sbio->bi_status = 0;
2165 bio_for_each_segment_all(bi, sbio, iter_all)
2166 page_len[j++] = bi->bv_len;
2169 for (j = vcnt; j-- ; ) {
2170 if (memcmp(page_address(ppages[j]),
2171 page_address(spages[j]),
2178 atomic64_add(r1_bio->sectors, &mddev->resync_mismatches);
2179 if (j < 0 || (test_bit(MD_RECOVERY_CHECK, &mddev->recovery)
2181 /* No need to write to this device. */
2182 sbio->bi_end_io = NULL;
2183 rdev_dec_pending(conf->mirrors[i].rdev, mddev);
2187 bio_copy_data(sbio, pbio);
2191 static void sync_request_write(struct mddev *mddev, struct r1bio *r1_bio)
2193 struct r1conf *conf = mddev->private;
2195 int disks = conf->raid_disks * 2;
2198 if (!test_bit(R1BIO_Uptodate, &r1_bio->state))
2199 /* ouch - failed to read all of that. */
2200 if (!fix_sync_read_error(r1_bio))
2203 if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
2204 process_checks(r1_bio);
2209 atomic_set(&r1_bio->remaining, 1);
2210 for (i = 0; i < disks ; i++) {
2211 wbio = r1_bio->bios[i];
2212 if (wbio->bi_end_io == NULL ||
2213 (wbio->bi_end_io == end_sync_read &&
2214 (i == r1_bio->read_disk ||
2215 !test_bit(MD_RECOVERY_SYNC, &mddev->recovery))))
2217 if (test_bit(Faulty, &conf->mirrors[i].rdev->flags)) {
2218 abort_sync_write(mddev, r1_bio);
2222 bio_set_op_attrs(wbio, REQ_OP_WRITE, 0);
2223 if (test_bit(FailFast, &conf->mirrors[i].rdev->flags))
2224 wbio->bi_opf |= MD_FAILFAST;
2226 wbio->bi_end_io = end_sync_write;
2227 atomic_inc(&r1_bio->remaining);
2228 md_sync_acct(conf->mirrors[i].rdev->bdev, bio_sectors(wbio));
2230 generic_make_request(wbio);
2233 put_sync_write_buf(r1_bio, 1);
2237 * This is a kernel thread which:
2239 * 1. Retries failed read operations on working mirrors.
2240 * 2. Updates the raid superblock when problems encounter.
2241 * 3. Performs writes following reads for array synchronising.
2244 static void fix_read_error(struct r1conf *conf, int read_disk,
2245 sector_t sect, int sectors)
2247 struct mddev *mddev = conf->mddev;
2253 struct md_rdev *rdev;
2255 if (s > (PAGE_SIZE>>9))
2263 rdev = rcu_dereference(conf->mirrors[d].rdev);
2265 (test_bit(In_sync, &rdev->flags) ||
2266 (!test_bit(Faulty, &rdev->flags) &&
2267 rdev->recovery_offset >= sect + s)) &&
2268 is_badblock(rdev, sect, s,
2269 &first_bad, &bad_sectors) == 0) {
2270 atomic_inc(&rdev->nr_pending);
2272 if (sync_page_io(rdev, sect, s<<9,
2273 conf->tmppage, REQ_OP_READ, 0, false))
2275 rdev_dec_pending(rdev, mddev);
2281 if (d == conf->raid_disks * 2)
2283 } while (!success && d != read_disk);
2286 /* Cannot read from anywhere - mark it bad */
2287 struct md_rdev *rdev = conf->mirrors[read_disk].rdev;
2288 if (!rdev_set_badblocks(rdev, sect, s, 0))
2289 md_error(mddev, rdev);
2292 /* write it back and re-read */
2294 while (d != read_disk) {
2296 d = conf->raid_disks * 2;
2299 rdev = rcu_dereference(conf->mirrors[d].rdev);
2301 !test_bit(Faulty, &rdev->flags)) {
2302 atomic_inc(&rdev->nr_pending);
2304 r1_sync_page_io(rdev, sect, s,
2305 conf->tmppage, WRITE);
2306 rdev_dec_pending(rdev, mddev);
2311 while (d != read_disk) {
2312 char b[BDEVNAME_SIZE];
2314 d = conf->raid_disks * 2;
2317 rdev = rcu_dereference(conf->mirrors[d].rdev);
2319 !test_bit(Faulty, &rdev->flags)) {
2320 atomic_inc(&rdev->nr_pending);
2322 if (r1_sync_page_io(rdev, sect, s,
2323 conf->tmppage, READ)) {
2324 atomic_add(s, &rdev->corrected_errors);
2325 pr_info("md/raid1:%s: read error corrected (%d sectors at %llu on %s)\n",
2327 (unsigned long long)(sect +
2329 bdevname(rdev->bdev, b));
2331 rdev_dec_pending(rdev, mddev);
2340 static int narrow_write_error(struct r1bio *r1_bio, int i)
2342 struct mddev *mddev = r1_bio->mddev;
2343 struct r1conf *conf = mddev->private;
2344 struct md_rdev *rdev = conf->mirrors[i].rdev;
2346 /* bio has the data to be written to device 'i' where
2347 * we just recently had a write error.
2348 * We repeatedly clone the bio and trim down to one block,
2349 * then try the write. Where the write fails we record
2351 * It is conceivable that the bio doesn't exactly align with
2352 * blocks. We must handle this somehow.
2354 * We currently own a reference on the rdev.
2360 int sect_to_write = r1_bio->sectors;
2363 if (rdev->badblocks.shift < 0)
2366 block_sectors = roundup(1 << rdev->badblocks.shift,
2367 bdev_logical_block_size(rdev->bdev) >> 9);
2368 sector = r1_bio->sector;
2369 sectors = ((sector + block_sectors)
2370 & ~(sector_t)(block_sectors - 1))
2373 while (sect_to_write) {
2375 if (sectors > sect_to_write)
2376 sectors = sect_to_write;
2377 /* Write at 'sector' for 'sectors'*/
2379 if (test_bit(R1BIO_BehindIO, &r1_bio->state)) {
2380 wbio = bio_clone_fast(r1_bio->behind_master_bio,
2384 wbio = bio_clone_fast(r1_bio->master_bio, GFP_NOIO,
2388 bio_set_op_attrs(wbio, REQ_OP_WRITE, 0);
2389 wbio->bi_iter.bi_sector = r1_bio->sector;
2390 wbio->bi_iter.bi_size = r1_bio->sectors << 9;
2392 bio_trim(wbio, sector - r1_bio->sector, sectors);
2393 wbio->bi_iter.bi_sector += rdev->data_offset;
2394 bio_set_dev(wbio, rdev->bdev);
2396 if (submit_bio_wait(wbio) < 0)
2398 ok = rdev_set_badblocks(rdev, sector,
2403 sect_to_write -= sectors;
2405 sectors = block_sectors;
2410 static void handle_sync_write_finished(struct r1conf *conf, struct r1bio *r1_bio)
2413 int s = r1_bio->sectors;
2414 for (m = 0; m < conf->raid_disks * 2 ; m++) {
2415 struct md_rdev *rdev = conf->mirrors[m].rdev;
2416 struct bio *bio = r1_bio->bios[m];
2417 if (bio->bi_end_io == NULL)
2419 if (!bio->bi_status &&
2420 test_bit(R1BIO_MadeGood, &r1_bio->state)) {
2421 rdev_clear_badblocks(rdev, r1_bio->sector, s, 0);
2423 if (bio->bi_status &&
2424 test_bit(R1BIO_WriteError, &r1_bio->state)) {
2425 if (!rdev_set_badblocks(rdev, r1_bio->sector, s, 0))
2426 md_error(conf->mddev, rdev);
2430 md_done_sync(conf->mddev, s, 1);
2433 static void handle_write_finished(struct r1conf *conf, struct r1bio *r1_bio)
2438 for (m = 0; m < conf->raid_disks * 2 ; m++)
2439 if (r1_bio->bios[m] == IO_MADE_GOOD) {
2440 struct md_rdev *rdev = conf->mirrors[m].rdev;
2441 rdev_clear_badblocks(rdev,
2443 r1_bio->sectors, 0);
2444 rdev_dec_pending(rdev, conf->mddev);
2445 } else if (r1_bio->bios[m] != NULL) {
2446 /* This drive got a write error. We need to
2447 * narrow down and record precise write
2451 if (!narrow_write_error(r1_bio, m)) {
2452 md_error(conf->mddev,
2453 conf->mirrors[m].rdev);
2454 /* an I/O failed, we can't clear the bitmap */
2455 set_bit(R1BIO_Degraded, &r1_bio->state);
2457 rdev_dec_pending(conf->mirrors[m].rdev,
2461 spin_lock_irq(&conf->device_lock);
2462 list_add(&r1_bio->retry_list, &conf->bio_end_io_list);
2463 idx = sector_to_idx(r1_bio->sector);
2464 atomic_inc(&conf->nr_queued[idx]);
2465 spin_unlock_irq(&conf->device_lock);
2467 * In case freeze_array() is waiting for condition
2468 * get_unqueued_pending() == extra to be true.
2470 wake_up(&conf->wait_barrier);
2471 md_wakeup_thread(conf->mddev->thread);
2473 if (test_bit(R1BIO_WriteError, &r1_bio->state))
2474 close_write(r1_bio);
2475 raid_end_bio_io(r1_bio);
2479 static void handle_read_error(struct r1conf *conf, struct r1bio *r1_bio)
2481 struct mddev *mddev = conf->mddev;
2483 struct md_rdev *rdev;
2485 clear_bit(R1BIO_ReadError, &r1_bio->state);
2486 /* we got a read error. Maybe the drive is bad. Maybe just
2487 * the block and we can fix it.
2488 * We freeze all other IO, and try reading the block from
2489 * other devices. When we find one, we re-write
2490 * and check it that fixes the read error.
2491 * This is all done synchronously while the array is
2495 bio = r1_bio->bios[r1_bio->read_disk];
2497 r1_bio->bios[r1_bio->read_disk] = NULL;
2499 rdev = conf->mirrors[r1_bio->read_disk].rdev;
2501 && !test_bit(FailFast, &rdev->flags)) {
2502 freeze_array(conf, 1);
2503 fix_read_error(conf, r1_bio->read_disk,
2504 r1_bio->sector, r1_bio->sectors);
2505 unfreeze_array(conf);
2506 } else if (mddev->ro == 0 && test_bit(FailFast, &rdev->flags)) {
2507 md_error(mddev, rdev);
2509 r1_bio->bios[r1_bio->read_disk] = IO_BLOCKED;
2512 rdev_dec_pending(rdev, conf->mddev);
2513 allow_barrier(conf, r1_bio->sector);
2514 bio = r1_bio->master_bio;
2516 /* Reuse the old r1_bio so that the IO_BLOCKED settings are preserved */
2518 raid1_read_request(mddev, bio, r1_bio->sectors, r1_bio);
2521 static void raid1d(struct md_thread *thread)
2523 struct mddev *mddev = thread->mddev;
2524 struct r1bio *r1_bio;
2525 unsigned long flags;
2526 struct r1conf *conf = mddev->private;
2527 struct list_head *head = &conf->retry_list;
2528 struct blk_plug plug;
2531 md_check_recovery(mddev);
2533 if (!list_empty_careful(&conf->bio_end_io_list) &&
2534 !test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags)) {
2536 spin_lock_irqsave(&conf->device_lock, flags);
2537 if (!test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags))
2538 list_splice_init(&conf->bio_end_io_list, &tmp);
2539 spin_unlock_irqrestore(&conf->device_lock, flags);
2540 while (!list_empty(&tmp)) {
2541 r1_bio = list_first_entry(&tmp, struct r1bio,
2543 list_del(&r1_bio->retry_list);
2544 idx = sector_to_idx(r1_bio->sector);
2545 atomic_dec(&conf->nr_queued[idx]);
2546 if (mddev->degraded)
2547 set_bit(R1BIO_Degraded, &r1_bio->state);
2548 if (test_bit(R1BIO_WriteError, &r1_bio->state))
2549 close_write(r1_bio);
2550 raid_end_bio_io(r1_bio);
2554 blk_start_plug(&plug);
2557 flush_pending_writes(conf);
2559 spin_lock_irqsave(&conf->device_lock, flags);
2560 if (list_empty(head)) {
2561 spin_unlock_irqrestore(&conf->device_lock, flags);
2564 r1_bio = list_entry(head->prev, struct r1bio, retry_list);
2565 list_del(head->prev);
2566 idx = sector_to_idx(r1_bio->sector);
2567 atomic_dec(&conf->nr_queued[idx]);
2568 spin_unlock_irqrestore(&conf->device_lock, flags);
2570 mddev = r1_bio->mddev;
2571 conf = mddev->private;
2572 if (test_bit(R1BIO_IsSync, &r1_bio->state)) {
2573 if (test_bit(R1BIO_MadeGood, &r1_bio->state) ||
2574 test_bit(R1BIO_WriteError, &r1_bio->state))
2575 handle_sync_write_finished(conf, r1_bio);
2577 sync_request_write(mddev, r1_bio);
2578 } else if (test_bit(R1BIO_MadeGood, &r1_bio->state) ||
2579 test_bit(R1BIO_WriteError, &r1_bio->state))
2580 handle_write_finished(conf, r1_bio);
2581 else if (test_bit(R1BIO_ReadError, &r1_bio->state))
2582 handle_read_error(conf, r1_bio);
2587 if (mddev->sb_flags & ~(1<<MD_SB_CHANGE_PENDING))
2588 md_check_recovery(mddev);
2590 blk_finish_plug(&plug);
2593 static int init_resync(struct r1conf *conf)
2597 buffs = RESYNC_WINDOW / RESYNC_BLOCK_SIZE;
2598 BUG_ON(mempool_initialized(&conf->r1buf_pool));
2600 return mempool_init(&conf->r1buf_pool, buffs, r1buf_pool_alloc,
2601 r1buf_pool_free, conf->poolinfo);
2604 static struct r1bio *raid1_alloc_init_r1buf(struct r1conf *conf)
2606 struct r1bio *r1bio = mempool_alloc(&conf->r1buf_pool, GFP_NOIO);
2607 struct resync_pages *rps;
2611 for (i = conf->poolinfo->raid_disks; i--; ) {
2612 bio = r1bio->bios[i];
2613 rps = bio->bi_private;
2615 bio->bi_private = rps;
2617 r1bio->master_bio = NULL;
2622 * perform a "sync" on one "block"
2624 * We need to make sure that no normal I/O request - particularly write
2625 * requests - conflict with active sync requests.
2627 * This is achieved by tracking pending requests and a 'barrier' concept
2628 * that can be installed to exclude normal IO requests.
2631 static sector_t raid1_sync_request(struct mddev *mddev, sector_t sector_nr,
2634 struct r1conf *conf = mddev->private;
2635 struct r1bio *r1_bio;
2637 sector_t max_sector, nr_sectors;
2641 int write_targets = 0, read_targets = 0;
2642 sector_t sync_blocks;
2643 int still_degraded = 0;
2644 int good_sectors = RESYNC_SECTORS;
2645 int min_bad = 0; /* number of sectors that are bad in all devices */
2646 int idx = sector_to_idx(sector_nr);
2649 if (!mempool_initialized(&conf->r1buf_pool))
2650 if (init_resync(conf))
2653 max_sector = mddev->dev_sectors;
2654 if (sector_nr >= max_sector) {
2655 /* If we aborted, we need to abort the
2656 * sync on the 'current' bitmap chunk (there will
2657 * only be one in raid1 resync.
2658 * We can find the current addess in mddev->curr_resync
2660 if (mddev->curr_resync < max_sector) /* aborted */
2661 md_bitmap_end_sync(mddev->bitmap, mddev->curr_resync,
2663 else /* completed sync */
2666 md_bitmap_close_sync(mddev->bitmap);
2669 if (mddev_is_clustered(mddev)) {
2670 conf->cluster_sync_low = 0;
2671 conf->cluster_sync_high = 0;
2676 if (mddev->bitmap == NULL &&
2677 mddev->recovery_cp == MaxSector &&
2678 !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery) &&
2679 conf->fullsync == 0) {
2681 return max_sector - sector_nr;
2683 /* before building a request, check if we can skip these blocks..
2684 * This call the bitmap_start_sync doesn't actually record anything
2686 if (!md_bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, 1) &&
2687 !conf->fullsync && !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) {
2688 /* We can skip this block, and probably several more */
2694 * If there is non-resync activity waiting for a turn, then let it
2695 * though before starting on this new sync request.
2697 if (atomic_read(&conf->nr_waiting[idx]))
2698 schedule_timeout_uninterruptible(1);
2700 /* we are incrementing sector_nr below. To be safe, we check against
2701 * sector_nr + two times RESYNC_SECTORS
2704 md_bitmap_cond_end_sync(mddev->bitmap, sector_nr,
2705 mddev_is_clustered(mddev) && (sector_nr + 2 * RESYNC_SECTORS > conf->cluster_sync_high));
2708 if (raise_barrier(conf, sector_nr))
2711 r1_bio = raid1_alloc_init_r1buf(conf);
2715 * If we get a correctably read error during resync or recovery,
2716 * we might want to read from a different device. So we
2717 * flag all drives that could conceivably be read from for READ,
2718 * and any others (which will be non-In_sync devices) for WRITE.
2719 * If a read fails, we try reading from something else for which READ
2723 r1_bio->mddev = mddev;
2724 r1_bio->sector = sector_nr;
2726 set_bit(R1BIO_IsSync, &r1_bio->state);
2727 /* make sure good_sectors won't go across barrier unit boundary */
2728 good_sectors = align_to_barrier_unit_end(sector_nr, good_sectors);
2730 for (i = 0; i < conf->raid_disks * 2; i++) {
2731 struct md_rdev *rdev;
2732 bio = r1_bio->bios[i];
2734 rdev = rcu_dereference(conf->mirrors[i].rdev);
2736 test_bit(Faulty, &rdev->flags)) {
2737 if (i < conf->raid_disks)
2739 } else if (!test_bit(In_sync, &rdev->flags)) {
2740 bio_set_op_attrs(bio, REQ_OP_WRITE, 0);
2741 bio->bi_end_io = end_sync_write;
2744 /* may need to read from here */
2745 sector_t first_bad = MaxSector;
2748 if (is_badblock(rdev, sector_nr, good_sectors,
2749 &first_bad, &bad_sectors)) {
2750 if (first_bad > sector_nr)
2751 good_sectors = first_bad - sector_nr;
2753 bad_sectors -= (sector_nr - first_bad);
2755 min_bad > bad_sectors)
2756 min_bad = bad_sectors;
2759 if (sector_nr < first_bad) {
2760 if (test_bit(WriteMostly, &rdev->flags)) {
2767 bio_set_op_attrs(bio, REQ_OP_READ, 0);
2768 bio->bi_end_io = end_sync_read;
2770 } else if (!test_bit(WriteErrorSeen, &rdev->flags) &&
2771 test_bit(MD_RECOVERY_SYNC, &mddev->recovery) &&
2772 !test_bit(MD_RECOVERY_CHECK, &mddev->recovery)) {
2774 * The device is suitable for reading (InSync),
2775 * but has bad block(s) here. Let's try to correct them,
2776 * if we are doing resync or repair. Otherwise, leave
2777 * this device alone for this sync request.
2779 bio_set_op_attrs(bio, REQ_OP_WRITE, 0);
2780 bio->bi_end_io = end_sync_write;
2784 if (rdev && bio->bi_end_io) {
2785 atomic_inc(&rdev->nr_pending);
2786 bio->bi_iter.bi_sector = sector_nr + rdev->data_offset;
2787 bio_set_dev(bio, rdev->bdev);
2788 if (test_bit(FailFast, &rdev->flags))
2789 bio->bi_opf |= MD_FAILFAST;
2795 r1_bio->read_disk = disk;
2797 if (read_targets == 0 && min_bad > 0) {
2798 /* These sectors are bad on all InSync devices, so we
2799 * need to mark them bad on all write targets
2802 for (i = 0 ; i < conf->raid_disks * 2 ; i++)
2803 if (r1_bio->bios[i]->bi_end_io == end_sync_write) {
2804 struct md_rdev *rdev = conf->mirrors[i].rdev;
2805 ok = rdev_set_badblocks(rdev, sector_nr,
2809 set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
2814 /* Cannot record the badblocks, so need to
2816 * If there are multiple read targets, could just
2817 * fail the really bad ones ???
2819 conf->recovery_disabled = mddev->recovery_disabled;
2820 set_bit(MD_RECOVERY_INTR, &mddev->recovery);
2826 if (min_bad > 0 && min_bad < good_sectors) {
2827 /* only resync enough to reach the next bad->good
2829 good_sectors = min_bad;
2832 if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) && read_targets > 0)
2833 /* extra read targets are also write targets */
2834 write_targets += read_targets-1;
2836 if (write_targets == 0 || read_targets == 0) {
2837 /* There is nowhere to write, so all non-sync
2838 * drives must be failed - so we are finished
2842 max_sector = sector_nr + min_bad;
2843 rv = max_sector - sector_nr;
2849 if (max_sector > mddev->resync_max)
2850 max_sector = mddev->resync_max; /* Don't do IO beyond here */
2851 if (max_sector > sector_nr + good_sectors)
2852 max_sector = sector_nr + good_sectors;
2857 int len = PAGE_SIZE;
2858 if (sector_nr + (len>>9) > max_sector)
2859 len = (max_sector - sector_nr) << 9;
2862 if (sync_blocks == 0) {
2863 if (!md_bitmap_start_sync(mddev->bitmap, sector_nr,
2864 &sync_blocks, still_degraded) &&
2866 !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
2868 if ((len >> 9) > sync_blocks)
2869 len = sync_blocks<<9;
2872 for (i = 0 ; i < conf->raid_disks * 2; i++) {
2873 struct resync_pages *rp;
2875 bio = r1_bio->bios[i];
2876 rp = get_resync_pages(bio);
2877 if (bio->bi_end_io) {
2878 page = resync_fetch_page(rp, page_idx);
2881 * won't fail because the vec table is big
2882 * enough to hold all these pages
2884 bio_add_page(bio, page, len, 0);
2887 nr_sectors += len>>9;
2888 sector_nr += len>>9;
2889 sync_blocks -= (len>>9);
2890 } while (++page_idx < RESYNC_PAGES);
2892 r1_bio->sectors = nr_sectors;
2894 if (mddev_is_clustered(mddev) &&
2895 conf->cluster_sync_high < sector_nr + nr_sectors) {
2896 conf->cluster_sync_low = mddev->curr_resync_completed;
2897 conf->cluster_sync_high = conf->cluster_sync_low + CLUSTER_RESYNC_WINDOW_SECTORS;
2898 /* Send resync message */
2899 md_cluster_ops->resync_info_update(mddev,
2900 conf->cluster_sync_low,
2901 conf->cluster_sync_high);
2904 /* For a user-requested sync, we read all readable devices and do a
2907 if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) {
2908 atomic_set(&r1_bio->remaining, read_targets);
2909 for (i = 0; i < conf->raid_disks * 2 && read_targets; i++) {
2910 bio = r1_bio->bios[i];
2911 if (bio->bi_end_io == end_sync_read) {
2913 md_sync_acct_bio(bio, nr_sectors);
2914 if (read_targets == 1)
2915 bio->bi_opf &= ~MD_FAILFAST;
2916 generic_make_request(bio);
2920 atomic_set(&r1_bio->remaining, 1);
2921 bio = r1_bio->bios[r1_bio->read_disk];
2922 md_sync_acct_bio(bio, nr_sectors);
2923 if (read_targets == 1)
2924 bio->bi_opf &= ~MD_FAILFAST;
2925 generic_make_request(bio);
2930 static sector_t raid1_size(struct mddev *mddev, sector_t sectors, int raid_disks)
2935 return mddev->dev_sectors;
2938 static struct r1conf *setup_conf(struct mddev *mddev)
2940 struct r1conf *conf;
2942 struct raid1_info *disk;
2943 struct md_rdev *rdev;
2946 conf = kzalloc(sizeof(struct r1conf), GFP_KERNEL);
2950 conf->nr_pending = kcalloc(BARRIER_BUCKETS_NR,
2951 sizeof(atomic_t), GFP_KERNEL);
2952 if (!conf->nr_pending)
2955 conf->nr_waiting = kcalloc(BARRIER_BUCKETS_NR,
2956 sizeof(atomic_t), GFP_KERNEL);
2957 if (!conf->nr_waiting)
2960 conf->nr_queued = kcalloc(BARRIER_BUCKETS_NR,
2961 sizeof(atomic_t), GFP_KERNEL);
2962 if (!conf->nr_queued)
2965 conf->barrier = kcalloc(BARRIER_BUCKETS_NR,
2966 sizeof(atomic_t), GFP_KERNEL);
2970 conf->mirrors = kzalloc(array3_size(sizeof(struct raid1_info),
2971 mddev->raid_disks, 2),
2976 conf->tmppage = alloc_page(GFP_KERNEL);
2980 conf->poolinfo = kzalloc(sizeof(*conf->poolinfo), GFP_KERNEL);
2981 if (!conf->poolinfo)
2983 conf->poolinfo->raid_disks = mddev->raid_disks * 2;
2984 err = mempool_init(&conf->r1bio_pool, NR_RAID_BIOS, r1bio_pool_alloc,
2985 rbio_pool_free, conf->poolinfo);
2989 err = bioset_init(&conf->bio_split, BIO_POOL_SIZE, 0, 0);
2993 conf->poolinfo->mddev = mddev;
2996 spin_lock_init(&conf->device_lock);
2997 rdev_for_each(rdev, mddev) {
2998 int disk_idx = rdev->raid_disk;
2999 if (disk_idx >= mddev->raid_disks
3002 if (test_bit(Replacement, &rdev->flags))
3003 disk = conf->mirrors + mddev->raid_disks + disk_idx;
3005 disk = conf->mirrors + disk_idx;
3010 disk->head_position = 0;
3011 disk->seq_start = MaxSector;
3013 conf->raid_disks = mddev->raid_disks;
3014 conf->mddev = mddev;
3015 INIT_LIST_HEAD(&conf->retry_list);
3016 INIT_LIST_HEAD(&conf->bio_end_io_list);
3018 spin_lock_init(&conf->resync_lock);
3019 init_waitqueue_head(&conf->wait_barrier);
3021 bio_list_init(&conf->pending_bio_list);
3022 conf->pending_count = 0;
3023 conf->recovery_disabled = mddev->recovery_disabled - 1;
3026 for (i = 0; i < conf->raid_disks * 2; i++) {
3028 disk = conf->mirrors + i;
3030 if (i < conf->raid_disks &&
3031 disk[conf->raid_disks].rdev) {
3032 /* This slot has a replacement. */
3034 /* No original, just make the replacement
3035 * a recovering spare
3038 disk[conf->raid_disks].rdev;
3039 disk[conf->raid_disks].rdev = NULL;
3040 } else if (!test_bit(In_sync, &disk->rdev->flags))
3041 /* Original is not in_sync - bad */
3046 !test_bit(In_sync, &disk->rdev->flags)) {
3047 disk->head_position = 0;
3049 (disk->rdev->saved_raid_disk < 0))
3055 conf->thread = md_register_thread(raid1d, mddev, "raid1");
3063 mempool_exit(&conf->r1bio_pool);
3064 kfree(conf->mirrors);
3065 safe_put_page(conf->tmppage);
3066 kfree(conf->poolinfo);
3067 kfree(conf->nr_pending);
3068 kfree(conf->nr_waiting);
3069 kfree(conf->nr_queued);
3070 kfree(conf->barrier);
3071 bioset_exit(&conf->bio_split);
3074 return ERR_PTR(err);
3077 static void raid1_free(struct mddev *mddev, void *priv);
3078 static int raid1_run(struct mddev *mddev)
3080 struct r1conf *conf;
3082 struct md_rdev *rdev;
3084 bool discard_supported = false;
3086 if (mddev->level != 1) {
3087 pr_warn("md/raid1:%s: raid level not set to mirroring (%d)\n",
3088 mdname(mddev), mddev->level);
3091 if (mddev->reshape_position != MaxSector) {
3092 pr_warn("md/raid1:%s: reshape_position set but not supported\n",
3096 if (mddev_init_writes_pending(mddev) < 0)
3099 * copy the already verified devices into our private RAID1
3100 * bookkeeping area. [whatever we allocate in run(),
3101 * should be freed in raid1_free()]
3103 if (mddev->private == NULL)
3104 conf = setup_conf(mddev);
3106 conf = mddev->private;
3109 return PTR_ERR(conf);
3112 blk_queue_max_write_same_sectors(mddev->queue, 0);
3113 blk_queue_max_write_zeroes_sectors(mddev->queue, 0);
3116 rdev_for_each(rdev, mddev) {
3117 if (!mddev->gendisk)
3119 disk_stack_limits(mddev->gendisk, rdev->bdev,
3120 rdev->data_offset << 9);
3121 if (blk_queue_discard(bdev_get_queue(rdev->bdev)))
3122 discard_supported = true;
3125 mddev->degraded = 0;
3126 for (i = 0; i < conf->raid_disks; i++)
3127 if (conf->mirrors[i].rdev == NULL ||
3128 !test_bit(In_sync, &conf->mirrors[i].rdev->flags) ||
3129 test_bit(Faulty, &conf->mirrors[i].rdev->flags))
3132 * RAID1 needs at least one disk in active
3134 if (conf->raid_disks - mddev->degraded < 1) {
3139 if (conf->raid_disks - mddev->degraded == 1)
3140 mddev->recovery_cp = MaxSector;
3142 if (mddev->recovery_cp != MaxSector)
3143 pr_info("md/raid1:%s: not clean -- starting background reconstruction\n",
3145 pr_info("md/raid1:%s: active with %d out of %d mirrors\n",
3146 mdname(mddev), mddev->raid_disks - mddev->degraded,
3150 * Ok, everything is just fine now
3152 mddev->thread = conf->thread;
3153 conf->thread = NULL;
3154 mddev->private = conf;
3155 set_bit(MD_FAILFAST_SUPPORTED, &mddev->flags);
3157 md_set_array_sectors(mddev, raid1_size(mddev, 0, 0));
3160 if (discard_supported)
3161 blk_queue_flag_set(QUEUE_FLAG_DISCARD,
3164 blk_queue_flag_clear(QUEUE_FLAG_DISCARD,
3168 ret = md_integrity_register(mddev);
3170 md_unregister_thread(&mddev->thread);
3176 raid1_free(mddev, conf);
3180 static void raid1_free(struct mddev *mddev, void *priv)
3182 struct r1conf *conf = priv;
3184 mempool_exit(&conf->r1bio_pool);
3185 kfree(conf->mirrors);
3186 safe_put_page(conf->tmppage);
3187 kfree(conf->poolinfo);
3188 kfree(conf->nr_pending);
3189 kfree(conf->nr_waiting);
3190 kfree(conf->nr_queued);
3191 kfree(conf->barrier);
3192 bioset_exit(&conf->bio_split);
3196 static int raid1_resize(struct mddev *mddev, sector_t sectors)
3198 /* no resync is happening, and there is enough space
3199 * on all devices, so we can resize.
3200 * We need to make sure resync covers any new space.
3201 * If the array is shrinking we should possibly wait until
3202 * any io in the removed space completes, but it hardly seems
3205 sector_t newsize = raid1_size(mddev, sectors, 0);
3206 if (mddev->external_size &&
3207 mddev->array_sectors > newsize)
3209 if (mddev->bitmap) {
3210 int ret = md_bitmap_resize(mddev->bitmap, newsize, 0, 0);
3214 md_set_array_sectors(mddev, newsize);
3215 if (sectors > mddev->dev_sectors &&
3216 mddev->recovery_cp > mddev->dev_sectors) {
3217 mddev->recovery_cp = mddev->dev_sectors;
3218 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3220 mddev->dev_sectors = sectors;
3221 mddev->resync_max_sectors = sectors;
3225 static int raid1_reshape(struct mddev *mddev)
3228 * 1/ resize the r1bio_pool
3229 * 2/ resize conf->mirrors
3231 * We allocate a new r1bio_pool if we can.
3232 * Then raise a device barrier and wait until all IO stops.
3233 * Then resize conf->mirrors and swap in the new r1bio pool.
3235 * At the same time, we "pack" the devices so that all the missing
3236 * devices have the higher raid_disk numbers.
3238 mempool_t newpool, oldpool;
3239 struct pool_info *newpoolinfo;
3240 struct raid1_info *newmirrors;
3241 struct r1conf *conf = mddev->private;
3242 int cnt, raid_disks;
3243 unsigned long flags;
3247 memset(&newpool, 0, sizeof(newpool));
3248 memset(&oldpool, 0, sizeof(oldpool));
3250 /* Cannot change chunk_size, layout, or level */
3251 if (mddev->chunk_sectors != mddev->new_chunk_sectors ||
3252 mddev->layout != mddev->new_layout ||
3253 mddev->level != mddev->new_level) {
3254 mddev->new_chunk_sectors = mddev->chunk_sectors;
3255 mddev->new_layout = mddev->layout;
3256 mddev->new_level = mddev->level;
3260 if (!mddev_is_clustered(mddev))
3261 md_allow_write(mddev);
3263 raid_disks = mddev->raid_disks + mddev->delta_disks;
3265 if (raid_disks < conf->raid_disks) {
3267 for (d= 0; d < conf->raid_disks; d++)
3268 if (conf->mirrors[d].rdev)
3270 if (cnt > raid_disks)
3274 newpoolinfo = kmalloc(sizeof(*newpoolinfo), GFP_KERNEL);
3277 newpoolinfo->mddev = mddev;
3278 newpoolinfo->raid_disks = raid_disks * 2;
3280 ret = mempool_init(&newpool, NR_RAID_BIOS, r1bio_pool_alloc,
3281 rbio_pool_free, newpoolinfo);
3286 newmirrors = kzalloc(array3_size(sizeof(struct raid1_info),
3291 mempool_exit(&newpool);
3295 freeze_array(conf, 0);
3297 /* ok, everything is stopped */
3298 oldpool = conf->r1bio_pool;
3299 conf->r1bio_pool = newpool;
3301 for (d = d2 = 0; d < conf->raid_disks; d++) {
3302 struct md_rdev *rdev = conf->mirrors[d].rdev;
3303 if (rdev && rdev->raid_disk != d2) {
3304 sysfs_unlink_rdev(mddev, rdev);
3305 rdev->raid_disk = d2;
3306 sysfs_unlink_rdev(mddev, rdev);
3307 if (sysfs_link_rdev(mddev, rdev))
3308 pr_warn("md/raid1:%s: cannot register rd%d\n",
3309 mdname(mddev), rdev->raid_disk);
3312 newmirrors[d2++].rdev = rdev;
3314 kfree(conf->mirrors);
3315 conf->mirrors = newmirrors;
3316 kfree(conf->poolinfo);
3317 conf->poolinfo = newpoolinfo;
3319 spin_lock_irqsave(&conf->device_lock, flags);
3320 mddev->degraded += (raid_disks - conf->raid_disks);
3321 spin_unlock_irqrestore(&conf->device_lock, flags);
3322 conf->raid_disks = mddev->raid_disks = raid_disks;
3323 mddev->delta_disks = 0;
3325 unfreeze_array(conf);
3327 set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
3328 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3329 md_wakeup_thread(mddev->thread);
3331 mempool_exit(&oldpool);
3335 static void raid1_quiesce(struct mddev *mddev, int quiesce)
3337 struct r1conf *conf = mddev->private;
3340 freeze_array(conf, 0);
3342 unfreeze_array(conf);
3345 static void *raid1_takeover(struct mddev *mddev)
3347 /* raid1 can take over:
3348 * raid5 with 2 devices, any layout or chunk size
3350 if (mddev->level == 5 && mddev->raid_disks == 2) {
3351 struct r1conf *conf;
3352 mddev->new_level = 1;
3353 mddev->new_layout = 0;
3354 mddev->new_chunk_sectors = 0;
3355 conf = setup_conf(mddev);
3356 if (!IS_ERR(conf)) {
3357 /* Array must appear to be quiesced */
3358 conf->array_frozen = 1;
3359 mddev_clear_unsupported_flags(mddev,
3360 UNSUPPORTED_MDDEV_FLAGS);
3364 return ERR_PTR(-EINVAL);
3367 static struct md_personality raid1_personality =
3371 .owner = THIS_MODULE,
3372 .make_request = raid1_make_request,
3375 .status = raid1_status,
3376 .error_handler = raid1_error,
3377 .hot_add_disk = raid1_add_disk,
3378 .hot_remove_disk= raid1_remove_disk,
3379 .spare_active = raid1_spare_active,
3380 .sync_request = raid1_sync_request,
3381 .resize = raid1_resize,
3383 .check_reshape = raid1_reshape,
3384 .quiesce = raid1_quiesce,
3385 .takeover = raid1_takeover,
3386 .congested = raid1_congested,
3389 static int __init raid_init(void)
3391 return register_md_personality(&raid1_personality);
3394 static void raid_exit(void)
3396 unregister_md_personality(&raid1_personality);
3399 module_init(raid_init);
3400 module_exit(raid_exit);
3401 MODULE_LICENSE("GPL");
3402 MODULE_DESCRIPTION("RAID1 (mirroring) personality for MD");
3403 MODULE_ALIAS("md-personality-3"); /* RAID1 */
3404 MODULE_ALIAS("md-raid1");
3405 MODULE_ALIAS("md-level-1");
3407 module_param(max_queued_requests, int, S_IRUGO|S_IWUSR);