2 * raid1.c : Multiple Devices driver for Linux
4 * Copyright (C) 1999, 2000, 2001 Ingo Molnar, Red Hat
6 * Copyright (C) 1996, 1997, 1998 Ingo Molnar, Miguel de Icaza, Gadi Oxman
8 * RAID-1 management functions.
10 * Better read-balancing code written by Mika Kuoppala <miku@iki.fi>, 2000
12 * Fixes to reconstruction by Jakob Østergaard" <jakob@ostenfeld.dk>
13 * Various fixes by Neil Brown <neilb@cse.unsw.edu.au>
15 * Changes by Peter T. Breuer <ptb@it.uc3m.es> 31/1/2003 to support
16 * bitmapped intelligence in resync:
18 * - bitmap marked during normal i/o
19 * - bitmap used to skip nondirty blocks during sync
21 * Additions to bitmap code, (C) 2003-2004 Paul Clements, SteelEye Technology:
22 * - persistent bitmap code
24 * This program is free software; you can redistribute it and/or modify
25 * it under the terms of the GNU General Public License as published by
26 * the Free Software Foundation; either version 2, or (at your option)
29 * You should have received a copy of the GNU General Public License
30 * (for example /usr/src/linux/COPYING); if not, write to the Free
31 * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
34 #include <linux/slab.h>
35 #include <linux/delay.h>
36 #include <linux/blkdev.h>
37 #include <linux/module.h>
38 #include <linux/seq_file.h>
39 #include <linux/ratelimit.h>
45 * Number of guaranteed r1bios in case of extreme VM load:
47 #define NR_RAID1_BIOS 256
49 /* when we get a read error on a read-only array, we redirect to another
50 * device without failing the first device, or trying to over-write to
51 * correct the read error. To keep track of bad blocks on a per-bio
52 * level, we store IO_BLOCKED in the appropriate 'bios' pointer
54 #define IO_BLOCKED ((struct bio *)1)
55 /* When we successfully write to a known bad-block, we need to remove the
56 * bad-block marking which must be done from process context. So we record
57 * the success by setting devs[n].bio to IO_MADE_GOOD
59 #define IO_MADE_GOOD ((struct bio *)2)
61 #define BIO_SPECIAL(bio) ((unsigned long)bio <= 2)
63 /* When there are this many requests queue to be written by
64 * the raid1 thread, we become 'congested' to provide back-pressure
67 static int max_queued_requests
= 1024;
69 static void allow_barrier(struct r1conf
*conf
, sector_t start_next_window
,
71 static void lower_barrier(struct r1conf
*conf
);
73 static void * r1bio_pool_alloc(gfp_t gfp_flags
, void *data
)
75 struct pool_info
*pi
= data
;
76 int size
= offsetof(struct r1bio
, bios
[pi
->raid_disks
]);
78 /* allocate a r1bio with room for raid_disks entries in the bios array */
79 return kzalloc(size
, gfp_flags
);
82 static void r1bio_pool_free(void *r1_bio
, void *data
)
87 #define RESYNC_BLOCK_SIZE (64*1024)
88 #define RESYNC_DEPTH 32
89 #define RESYNC_SECTORS (RESYNC_BLOCK_SIZE >> 9)
90 #define RESYNC_PAGES ((RESYNC_BLOCK_SIZE + PAGE_SIZE-1) / PAGE_SIZE)
91 #define RESYNC_WINDOW (RESYNC_BLOCK_SIZE * RESYNC_DEPTH)
92 #define RESYNC_WINDOW_SECTORS (RESYNC_WINDOW >> 9)
93 #define CLUSTER_RESYNC_WINDOW (16 * RESYNC_WINDOW)
94 #define CLUSTER_RESYNC_WINDOW_SECTORS (CLUSTER_RESYNC_WINDOW >> 9)
95 #define NEXT_NORMALIO_DISTANCE (3 * RESYNC_WINDOW_SECTORS)
97 static void * r1buf_pool_alloc(gfp_t gfp_flags
, void *data
)
99 struct pool_info
*pi
= data
;
100 struct r1bio
*r1_bio
;
105 r1_bio
= r1bio_pool_alloc(gfp_flags
, pi
);
110 * Allocate bios : 1 for reading, n-1 for writing
112 for (j
= pi
->raid_disks
; j
-- ; ) {
113 bio
= bio_kmalloc(gfp_flags
, RESYNC_PAGES
);
116 r1_bio
->bios
[j
] = bio
;
119 * Allocate RESYNC_PAGES data pages and attach them to
121 * If this is a user-requested check/repair, allocate
122 * RESYNC_PAGES for each bio.
124 if (test_bit(MD_RECOVERY_REQUESTED
, &pi
->mddev
->recovery
))
125 need_pages
= pi
->raid_disks
;
128 for (j
= 0; j
< need_pages
; j
++) {
129 bio
= r1_bio
->bios
[j
];
130 bio
->bi_vcnt
= RESYNC_PAGES
;
132 if (bio_alloc_pages(bio
, gfp_flags
))
135 /* If not user-requests, copy the page pointers to all bios */
136 if (!test_bit(MD_RECOVERY_REQUESTED
, &pi
->mddev
->recovery
)) {
137 for (i
=0; i
<RESYNC_PAGES
; i
++)
138 for (j
=1; j
<pi
->raid_disks
; j
++)
139 r1_bio
->bios
[j
]->bi_io_vec
[i
].bv_page
=
140 r1_bio
->bios
[0]->bi_io_vec
[i
].bv_page
;
143 r1_bio
->master_bio
= NULL
;
151 bio_for_each_segment_all(bv
, r1_bio
->bios
[j
], i
)
152 __free_page(bv
->bv_page
);
156 while (++j
< pi
->raid_disks
)
157 bio_put(r1_bio
->bios
[j
]);
158 r1bio_pool_free(r1_bio
, data
);
162 static void r1buf_pool_free(void *__r1_bio
, void *data
)
164 struct pool_info
*pi
= data
;
166 struct r1bio
*r1bio
= __r1_bio
;
168 for (i
= 0; i
< RESYNC_PAGES
; i
++)
169 for (j
= pi
->raid_disks
; j
-- ;) {
171 r1bio
->bios
[j
]->bi_io_vec
[i
].bv_page
!=
172 r1bio
->bios
[0]->bi_io_vec
[i
].bv_page
)
173 safe_put_page(r1bio
->bios
[j
]->bi_io_vec
[i
].bv_page
);
175 for (i
=0 ; i
< pi
->raid_disks
; i
++)
176 bio_put(r1bio
->bios
[i
]);
178 r1bio_pool_free(r1bio
, data
);
181 static void put_all_bios(struct r1conf
*conf
, struct r1bio
*r1_bio
)
185 for (i
= 0; i
< conf
->raid_disks
* 2; i
++) {
186 struct bio
**bio
= r1_bio
->bios
+ i
;
187 if (!BIO_SPECIAL(*bio
))
193 static void free_r1bio(struct r1bio
*r1_bio
)
195 struct r1conf
*conf
= r1_bio
->mddev
->private;
197 put_all_bios(conf
, r1_bio
);
198 mempool_free(r1_bio
, conf
->r1bio_pool
);
201 static void put_buf(struct r1bio
*r1_bio
)
203 struct r1conf
*conf
= r1_bio
->mddev
->private;
206 for (i
= 0; i
< conf
->raid_disks
* 2; i
++) {
207 struct bio
*bio
= r1_bio
->bios
[i
];
209 rdev_dec_pending(conf
->mirrors
[i
].rdev
, r1_bio
->mddev
);
212 mempool_free(r1_bio
, conf
->r1buf_pool
);
217 static void reschedule_retry(struct r1bio
*r1_bio
)
220 struct mddev
*mddev
= r1_bio
->mddev
;
221 struct r1conf
*conf
= mddev
->private;
223 spin_lock_irqsave(&conf
->device_lock
, flags
);
224 list_add(&r1_bio
->retry_list
, &conf
->retry_list
);
226 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
228 wake_up(&conf
->wait_barrier
);
229 md_wakeup_thread(mddev
->thread
);
233 * raid_end_bio_io() is called when we have finished servicing a mirrored
234 * operation and are ready to return a success/failure code to the buffer
237 static void call_bio_endio(struct r1bio
*r1_bio
)
239 struct bio
*bio
= r1_bio
->master_bio
;
241 struct r1conf
*conf
= r1_bio
->mddev
->private;
242 sector_t start_next_window
= r1_bio
->start_next_window
;
243 sector_t bi_sector
= bio
->bi_iter
.bi_sector
;
245 if (bio
->bi_phys_segments
) {
247 spin_lock_irqsave(&conf
->device_lock
, flags
);
248 bio
->bi_phys_segments
--;
249 done
= (bio
->bi_phys_segments
== 0);
250 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
252 * make_request() might be waiting for
253 * bi_phys_segments to decrease
255 wake_up(&conf
->wait_barrier
);
259 if (!test_bit(R1BIO_Uptodate
, &r1_bio
->state
))
260 bio
->bi_error
= -EIO
;
265 * Wake up any possible resync thread that waits for the device
268 allow_barrier(conf
, start_next_window
, bi_sector
);
272 static void raid_end_bio_io(struct r1bio
*r1_bio
)
274 struct bio
*bio
= r1_bio
->master_bio
;
276 /* if nobody has done the final endio yet, do it now */
277 if (!test_and_set_bit(R1BIO_Returned
, &r1_bio
->state
)) {
278 pr_debug("raid1: sync end %s on sectors %llu-%llu\n",
279 (bio_data_dir(bio
) == WRITE
) ? "write" : "read",
280 (unsigned long long) bio
->bi_iter
.bi_sector
,
281 (unsigned long long) bio_end_sector(bio
) - 1);
283 call_bio_endio(r1_bio
);
289 * Update disk head position estimator based on IRQ completion info.
291 static inline void update_head_pos(int disk
, struct r1bio
*r1_bio
)
293 struct r1conf
*conf
= r1_bio
->mddev
->private;
295 conf
->mirrors
[disk
].head_position
=
296 r1_bio
->sector
+ (r1_bio
->sectors
);
300 * Find the disk number which triggered given bio
302 static int find_bio_disk(struct r1bio
*r1_bio
, struct bio
*bio
)
305 struct r1conf
*conf
= r1_bio
->mddev
->private;
306 int raid_disks
= conf
->raid_disks
;
308 for (mirror
= 0; mirror
< raid_disks
* 2; mirror
++)
309 if (r1_bio
->bios
[mirror
] == bio
)
312 BUG_ON(mirror
== raid_disks
* 2);
313 update_head_pos(mirror
, r1_bio
);
318 static void raid1_end_read_request(struct bio
*bio
)
320 int uptodate
= !bio
->bi_error
;
321 struct r1bio
*r1_bio
= bio
->bi_private
;
322 struct r1conf
*conf
= r1_bio
->mddev
->private;
323 struct md_rdev
*rdev
= conf
->mirrors
[r1_bio
->read_disk
].rdev
;
326 * this branch is our 'one mirror IO has finished' event handler:
328 update_head_pos(r1_bio
->read_disk
, r1_bio
);
331 set_bit(R1BIO_Uptodate
, &r1_bio
->state
);
333 /* If all other devices have failed, we want to return
334 * the error upwards rather than fail the last device.
335 * Here we redefine "uptodate" to mean "Don't want to retry"
338 spin_lock_irqsave(&conf
->device_lock
, flags
);
339 if (r1_bio
->mddev
->degraded
== conf
->raid_disks
||
340 (r1_bio
->mddev
->degraded
== conf
->raid_disks
-1 &&
341 test_bit(In_sync
, &rdev
->flags
)))
343 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
347 raid_end_bio_io(r1_bio
);
348 rdev_dec_pending(rdev
, conf
->mddev
);
353 char b
[BDEVNAME_SIZE
];
355 KERN_ERR
"md/raid1:%s: %s: "
356 "rescheduling sector %llu\n",
360 (unsigned long long)r1_bio
->sector
);
361 set_bit(R1BIO_ReadError
, &r1_bio
->state
);
362 reschedule_retry(r1_bio
);
363 /* don't drop the reference on read_disk yet */
367 static void close_write(struct r1bio
*r1_bio
)
369 /* it really is the end of this request */
370 if (test_bit(R1BIO_BehindIO
, &r1_bio
->state
)) {
371 /* free extra copy of the data pages */
372 int i
= r1_bio
->behind_page_count
;
374 safe_put_page(r1_bio
->behind_bvecs
[i
].bv_page
);
375 kfree(r1_bio
->behind_bvecs
);
376 r1_bio
->behind_bvecs
= NULL
;
378 /* clear the bitmap if all writes complete successfully */
379 bitmap_endwrite(r1_bio
->mddev
->bitmap
, r1_bio
->sector
,
381 !test_bit(R1BIO_Degraded
, &r1_bio
->state
),
382 test_bit(R1BIO_BehindIO
, &r1_bio
->state
));
383 md_write_end(r1_bio
->mddev
);
386 static void r1_bio_write_done(struct r1bio
*r1_bio
)
388 if (!atomic_dec_and_test(&r1_bio
->remaining
))
391 if (test_bit(R1BIO_WriteError
, &r1_bio
->state
))
392 reschedule_retry(r1_bio
);
395 if (test_bit(R1BIO_MadeGood
, &r1_bio
->state
))
396 reschedule_retry(r1_bio
);
398 raid_end_bio_io(r1_bio
);
402 static void raid1_end_write_request(struct bio
*bio
)
404 struct r1bio
*r1_bio
= bio
->bi_private
;
405 int behind
= test_bit(R1BIO_BehindIO
, &r1_bio
->state
);
406 struct r1conf
*conf
= r1_bio
->mddev
->private;
407 struct bio
*to_put
= NULL
;
408 int mirror
= find_bio_disk(r1_bio
, bio
);
409 struct md_rdev
*rdev
= conf
->mirrors
[mirror
].rdev
;
412 * 'one mirror IO has finished' event handler:
415 set_bit(WriteErrorSeen
, &rdev
->flags
);
416 if (!test_and_set_bit(WantReplacement
, &rdev
->flags
))
417 set_bit(MD_RECOVERY_NEEDED
, &
418 conf
->mddev
->recovery
);
420 set_bit(R1BIO_WriteError
, &r1_bio
->state
);
423 * Set R1BIO_Uptodate in our master bio, so that we
424 * will return a good error code for to the higher
425 * levels even if IO on some other mirrored buffer
428 * The 'master' represents the composite IO operation
429 * to user-side. So if something waits for IO, then it
430 * will wait for the 'master' bio.
435 r1_bio
->bios
[mirror
] = NULL
;
438 * Do not set R1BIO_Uptodate if the current device is
439 * rebuilding or Faulty. This is because we cannot use
440 * such device for properly reading the data back (we could
441 * potentially use it, if the current write would have felt
442 * before rdev->recovery_offset, but for simplicity we don't
445 if (test_bit(In_sync
, &rdev
->flags
) &&
446 !test_bit(Faulty
, &rdev
->flags
))
447 set_bit(R1BIO_Uptodate
, &r1_bio
->state
);
449 /* Maybe we can clear some bad blocks. */
450 if (is_badblock(rdev
, r1_bio
->sector
, r1_bio
->sectors
,
451 &first_bad
, &bad_sectors
)) {
452 r1_bio
->bios
[mirror
] = IO_MADE_GOOD
;
453 set_bit(R1BIO_MadeGood
, &r1_bio
->state
);
458 if (test_bit(WriteMostly
, &rdev
->flags
))
459 atomic_dec(&r1_bio
->behind_remaining
);
462 * In behind mode, we ACK the master bio once the I/O
463 * has safely reached all non-writemostly
464 * disks. Setting the Returned bit ensures that this
465 * gets done only once -- we don't ever want to return
466 * -EIO here, instead we'll wait
468 if (atomic_read(&r1_bio
->behind_remaining
) >= (atomic_read(&r1_bio
->remaining
)-1) &&
469 test_bit(R1BIO_Uptodate
, &r1_bio
->state
)) {
470 /* Maybe we can return now */
471 if (!test_and_set_bit(R1BIO_Returned
, &r1_bio
->state
)) {
472 struct bio
*mbio
= r1_bio
->master_bio
;
473 pr_debug("raid1: behind end write sectors"
475 (unsigned long long) mbio
->bi_iter
.bi_sector
,
476 (unsigned long long) bio_end_sector(mbio
) - 1);
477 call_bio_endio(r1_bio
);
481 if (r1_bio
->bios
[mirror
] == NULL
)
482 rdev_dec_pending(rdev
, conf
->mddev
);
485 * Let's see if all mirrored write operations have finished
488 r1_bio_write_done(r1_bio
);
495 * This routine returns the disk from which the requested read should
496 * be done. There is a per-array 'next expected sequential IO' sector
497 * number - if this matches on the next IO then we use the last disk.
498 * There is also a per-disk 'last know head position' sector that is
499 * maintained from IRQ contexts, both the normal and the resync IO
500 * completion handlers update this position correctly. If there is no
501 * perfect sequential match then we pick the disk whose head is closest.
503 * If there are 2 mirrors in the same 2 devices, performance degrades
504 * because position is mirror, not device based.
506 * The rdev for the device selected will have nr_pending incremented.
508 static int read_balance(struct r1conf
*conf
, struct r1bio
*r1_bio
, int *max_sectors
)
510 const sector_t this_sector
= r1_bio
->sector
;
512 int best_good_sectors
;
513 int best_disk
, best_dist_disk
, best_pending_disk
;
517 unsigned int min_pending
;
518 struct md_rdev
*rdev
;
520 int choose_next_idle
;
524 * Check if we can balance. We can balance on the whole
525 * device if no resync is going on, or below the resync window.
526 * We take the first readable disk when above the resync window.
529 sectors
= r1_bio
->sectors
;
532 best_dist
= MaxSector
;
533 best_pending_disk
= -1;
534 min_pending
= UINT_MAX
;
535 best_good_sectors
= 0;
537 choose_next_idle
= 0;
539 if ((conf
->mddev
->recovery_cp
< this_sector
+ sectors
) ||
540 (mddev_is_clustered(conf
->mddev
) &&
541 md_cluster_ops
->area_resyncing(conf
->mddev
, READ
, this_sector
,
542 this_sector
+ sectors
)))
547 for (disk
= 0 ; disk
< conf
->raid_disks
* 2 ; disk
++) {
551 unsigned int pending
;
554 rdev
= rcu_dereference(conf
->mirrors
[disk
].rdev
);
555 if (r1_bio
->bios
[disk
] == IO_BLOCKED
557 || test_bit(Faulty
, &rdev
->flags
))
559 if (!test_bit(In_sync
, &rdev
->flags
) &&
560 rdev
->recovery_offset
< this_sector
+ sectors
)
562 if (test_bit(WriteMostly
, &rdev
->flags
)) {
563 /* Don't balance among write-mostly, just
564 * use the first as a last resort */
565 if (best_dist_disk
< 0) {
566 if (is_badblock(rdev
, this_sector
, sectors
,
567 &first_bad
, &bad_sectors
)) {
568 if (first_bad
<= this_sector
)
569 /* Cannot use this */
571 best_good_sectors
= first_bad
- this_sector
;
573 best_good_sectors
= sectors
;
574 best_dist_disk
= disk
;
575 best_pending_disk
= disk
;
579 /* This is a reasonable device to use. It might
582 if (is_badblock(rdev
, this_sector
, sectors
,
583 &first_bad
, &bad_sectors
)) {
584 if (best_dist
< MaxSector
)
585 /* already have a better device */
587 if (first_bad
<= this_sector
) {
588 /* cannot read here. If this is the 'primary'
589 * device, then we must not read beyond
590 * bad_sectors from another device..
592 bad_sectors
-= (this_sector
- first_bad
);
593 if (choose_first
&& sectors
> bad_sectors
)
594 sectors
= bad_sectors
;
595 if (best_good_sectors
> sectors
)
596 best_good_sectors
= sectors
;
599 sector_t good_sectors
= first_bad
- this_sector
;
600 if (good_sectors
> best_good_sectors
) {
601 best_good_sectors
= good_sectors
;
609 best_good_sectors
= sectors
;
611 nonrot
= blk_queue_nonrot(bdev_get_queue(rdev
->bdev
));
612 has_nonrot_disk
|= nonrot
;
613 pending
= atomic_read(&rdev
->nr_pending
);
614 dist
= abs(this_sector
- conf
->mirrors
[disk
].head_position
);
619 /* Don't change to another disk for sequential reads */
620 if (conf
->mirrors
[disk
].next_seq_sect
== this_sector
622 int opt_iosize
= bdev_io_opt(rdev
->bdev
) >> 9;
623 struct raid1_info
*mirror
= &conf
->mirrors
[disk
];
627 * If buffered sequential IO size exceeds optimal
628 * iosize, check if there is idle disk. If yes, choose
629 * the idle disk. read_balance could already choose an
630 * idle disk before noticing it's a sequential IO in
631 * this disk. This doesn't matter because this disk
632 * will idle, next time it will be utilized after the
633 * first disk has IO size exceeds optimal iosize. In
634 * this way, iosize of the first disk will be optimal
635 * iosize at least. iosize of the second disk might be
636 * small, but not a big deal since when the second disk
637 * starts IO, the first disk is likely still busy.
639 if (nonrot
&& opt_iosize
> 0 &&
640 mirror
->seq_start
!= MaxSector
&&
641 mirror
->next_seq_sect
> opt_iosize
&&
642 mirror
->next_seq_sect
- opt_iosize
>=
644 choose_next_idle
= 1;
649 /* If device is idle, use it */
655 if (choose_next_idle
)
658 if (min_pending
> pending
) {
659 min_pending
= pending
;
660 best_pending_disk
= disk
;
663 if (dist
< best_dist
) {
665 best_dist_disk
= disk
;
670 * If all disks are rotational, choose the closest disk. If any disk is
671 * non-rotational, choose the disk with less pending request even the
672 * disk is rotational, which might/might not be optimal for raids with
673 * mixed ratation/non-rotational disks depending on workload.
675 if (best_disk
== -1) {
677 best_disk
= best_pending_disk
;
679 best_disk
= best_dist_disk
;
682 if (best_disk
>= 0) {
683 rdev
= rcu_dereference(conf
->mirrors
[best_disk
].rdev
);
686 atomic_inc(&rdev
->nr_pending
);
687 sectors
= best_good_sectors
;
689 if (conf
->mirrors
[best_disk
].next_seq_sect
!= this_sector
)
690 conf
->mirrors
[best_disk
].seq_start
= this_sector
;
692 conf
->mirrors
[best_disk
].next_seq_sect
= this_sector
+ sectors
;
695 *max_sectors
= sectors
;
700 static int raid1_congested(struct mddev
*mddev
, int bits
)
702 struct r1conf
*conf
= mddev
->private;
705 if ((bits
& (1 << WB_async_congested
)) &&
706 conf
->pending_count
>= max_queued_requests
)
710 for (i
= 0; i
< conf
->raid_disks
* 2; i
++) {
711 struct md_rdev
*rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
712 if (rdev
&& !test_bit(Faulty
, &rdev
->flags
)) {
713 struct request_queue
*q
= bdev_get_queue(rdev
->bdev
);
717 /* Note the '|| 1' - when read_balance prefers
718 * non-congested targets, it can be removed
720 if ((bits
& (1 << WB_async_congested
)) || 1)
721 ret
|= bdi_congested(&q
->backing_dev_info
, bits
);
723 ret
&= bdi_congested(&q
->backing_dev_info
, bits
);
730 static void flush_pending_writes(struct r1conf
*conf
)
732 /* Any writes that have been queued but are awaiting
733 * bitmap updates get flushed here.
735 spin_lock_irq(&conf
->device_lock
);
737 if (conf
->pending_bio_list
.head
) {
739 bio
= bio_list_get(&conf
->pending_bio_list
);
740 conf
->pending_count
= 0;
741 spin_unlock_irq(&conf
->device_lock
);
742 /* flush any pending bitmap writes to
743 * disk before proceeding w/ I/O */
744 bitmap_unplug(conf
->mddev
->bitmap
);
745 wake_up(&conf
->wait_barrier
);
747 while (bio
) { /* submit pending writes */
748 struct bio
*next
= bio
->bi_next
;
750 if (unlikely((bio
->bi_rw
& REQ_DISCARD
) &&
751 !blk_queue_discard(bdev_get_queue(bio
->bi_bdev
))))
755 generic_make_request(bio
);
759 spin_unlock_irq(&conf
->device_lock
);
763 * Sometimes we need to suspend IO while we do something else,
764 * either some resync/recovery, or reconfigure the array.
765 * To do this we raise a 'barrier'.
766 * The 'barrier' is a counter that can be raised multiple times
767 * to count how many activities are happening which preclude
769 * We can only raise the barrier if there is no pending IO.
770 * i.e. if nr_pending == 0.
771 * We choose only to raise the barrier if no-one is waiting for the
772 * barrier to go down. This means that as soon as an IO request
773 * is ready, no other operations which require a barrier will start
774 * until the IO request has had a chance.
776 * So: regular IO calls 'wait_barrier'. When that returns there
777 * is no backgroup IO happening, It must arrange to call
778 * allow_barrier when it has finished its IO.
779 * backgroup IO calls must call raise_barrier. Once that returns
780 * there is no normal IO happeing. It must arrange to call
781 * lower_barrier when the particular background IO completes.
783 static void raise_barrier(struct r1conf
*conf
, sector_t sector_nr
)
785 spin_lock_irq(&conf
->resync_lock
);
787 /* Wait until no block IO is waiting */
788 wait_event_lock_irq(conf
->wait_barrier
, !conf
->nr_waiting
,
791 /* block any new IO from starting */
793 conf
->next_resync
= sector_nr
;
795 /* For these conditions we must wait:
796 * A: while the array is in frozen state
797 * B: while barrier >= RESYNC_DEPTH, meaning resync reach
798 * the max count which allowed.
799 * C: next_resync + RESYNC_SECTORS > start_next_window, meaning
800 * next resync will reach to the window which normal bios are
802 * D: while there are any active requests in the current window.
804 wait_event_lock_irq(conf
->wait_barrier
,
805 !conf
->array_frozen
&&
806 conf
->barrier
< RESYNC_DEPTH
&&
807 conf
->current_window_requests
== 0 &&
808 (conf
->start_next_window
>=
809 conf
->next_resync
+ RESYNC_SECTORS
),
813 spin_unlock_irq(&conf
->resync_lock
);
816 static void lower_barrier(struct r1conf
*conf
)
819 BUG_ON(conf
->barrier
<= 0);
820 spin_lock_irqsave(&conf
->resync_lock
, flags
);
823 spin_unlock_irqrestore(&conf
->resync_lock
, flags
);
824 wake_up(&conf
->wait_barrier
);
827 static bool need_to_wait_for_sync(struct r1conf
*conf
, struct bio
*bio
)
831 if (conf
->array_frozen
|| !bio
)
833 else if (conf
->barrier
&& bio_data_dir(bio
) == WRITE
) {
834 if ((conf
->mddev
->curr_resync_completed
835 >= bio_end_sector(bio
)) ||
836 (conf
->next_resync
+ NEXT_NORMALIO_DISTANCE
837 <= bio
->bi_iter
.bi_sector
))
846 static sector_t
wait_barrier(struct r1conf
*conf
, struct bio
*bio
)
850 spin_lock_irq(&conf
->resync_lock
);
851 if (need_to_wait_for_sync(conf
, bio
)) {
853 /* Wait for the barrier to drop.
854 * However if there are already pending
855 * requests (preventing the barrier from
856 * rising completely), and the
857 * per-process bio queue isn't empty,
858 * then don't wait, as we need to empty
859 * that queue to allow conf->start_next_window
862 wait_event_lock_irq(conf
->wait_barrier
,
863 !conf
->array_frozen
&&
865 ((conf
->start_next_window
<
866 conf
->next_resync
+ RESYNC_SECTORS
) &&
868 !bio_list_empty(current
->bio_list
))),
873 if (bio
&& bio_data_dir(bio
) == WRITE
) {
874 if (bio
->bi_iter
.bi_sector
>= conf
->next_resync
) {
875 if (conf
->start_next_window
== MaxSector
)
876 conf
->start_next_window
=
878 NEXT_NORMALIO_DISTANCE
;
880 if ((conf
->start_next_window
+ NEXT_NORMALIO_DISTANCE
)
881 <= bio
->bi_iter
.bi_sector
)
882 conf
->next_window_requests
++;
884 conf
->current_window_requests
++;
885 sector
= conf
->start_next_window
;
890 spin_unlock_irq(&conf
->resync_lock
);
894 static void allow_barrier(struct r1conf
*conf
, sector_t start_next_window
,
899 spin_lock_irqsave(&conf
->resync_lock
, flags
);
901 if (start_next_window
) {
902 if (start_next_window
== conf
->start_next_window
) {
903 if (conf
->start_next_window
+ NEXT_NORMALIO_DISTANCE
905 conf
->next_window_requests
--;
907 conf
->current_window_requests
--;
909 conf
->current_window_requests
--;
911 if (!conf
->current_window_requests
) {
912 if (conf
->next_window_requests
) {
913 conf
->current_window_requests
=
914 conf
->next_window_requests
;
915 conf
->next_window_requests
= 0;
916 conf
->start_next_window
+=
917 NEXT_NORMALIO_DISTANCE
;
919 conf
->start_next_window
= MaxSector
;
922 spin_unlock_irqrestore(&conf
->resync_lock
, flags
);
923 wake_up(&conf
->wait_barrier
);
926 static void freeze_array(struct r1conf
*conf
, int extra
)
928 /* stop syncio and normal IO and wait for everything to
930 * We wait until nr_pending match nr_queued+extra
931 * This is called in the context of one normal IO request
932 * that has failed. Thus any sync request that might be pending
933 * will be blocked by nr_pending, and we need to wait for
934 * pending IO requests to complete or be queued for re-try.
935 * Thus the number queued (nr_queued) plus this request (extra)
936 * must match the number of pending IOs (nr_pending) before
939 spin_lock_irq(&conf
->resync_lock
);
940 conf
->array_frozen
= 1;
941 wait_event_lock_irq_cmd(conf
->wait_barrier
,
942 conf
->nr_pending
== conf
->nr_queued
+extra
,
944 flush_pending_writes(conf
));
945 spin_unlock_irq(&conf
->resync_lock
);
947 static void unfreeze_array(struct r1conf
*conf
)
949 /* reverse the effect of the freeze */
950 spin_lock_irq(&conf
->resync_lock
);
951 conf
->array_frozen
= 0;
952 wake_up(&conf
->wait_barrier
);
953 spin_unlock_irq(&conf
->resync_lock
);
956 /* duplicate the data pages for behind I/O
958 static void alloc_behind_pages(struct bio
*bio
, struct r1bio
*r1_bio
)
961 struct bio_vec
*bvec
;
962 struct bio_vec
*bvecs
= kzalloc(bio
->bi_vcnt
* sizeof(struct bio_vec
),
964 if (unlikely(!bvecs
))
967 bio_for_each_segment_all(bvec
, bio
, i
) {
969 bvecs
[i
].bv_page
= alloc_page(GFP_NOIO
);
970 if (unlikely(!bvecs
[i
].bv_page
))
972 memcpy(kmap(bvecs
[i
].bv_page
) + bvec
->bv_offset
,
973 kmap(bvec
->bv_page
) + bvec
->bv_offset
, bvec
->bv_len
);
974 kunmap(bvecs
[i
].bv_page
);
975 kunmap(bvec
->bv_page
);
977 r1_bio
->behind_bvecs
= bvecs
;
978 r1_bio
->behind_page_count
= bio
->bi_vcnt
;
979 set_bit(R1BIO_BehindIO
, &r1_bio
->state
);
983 for (i
= 0; i
< bio
->bi_vcnt
; i
++)
984 if (bvecs
[i
].bv_page
)
985 put_page(bvecs
[i
].bv_page
);
987 pr_debug("%dB behind alloc failed, doing sync I/O\n",
988 bio
->bi_iter
.bi_size
);
991 struct raid1_plug_cb
{
992 struct blk_plug_cb cb
;
993 struct bio_list pending
;
997 static void raid1_unplug(struct blk_plug_cb
*cb
, bool from_schedule
)
999 struct raid1_plug_cb
*plug
= container_of(cb
, struct raid1_plug_cb
,
1001 struct mddev
*mddev
= plug
->cb
.data
;
1002 struct r1conf
*conf
= mddev
->private;
1005 if (from_schedule
|| current
->bio_list
) {
1006 spin_lock_irq(&conf
->device_lock
);
1007 bio_list_merge(&conf
->pending_bio_list
, &plug
->pending
);
1008 conf
->pending_count
+= plug
->pending_cnt
;
1009 spin_unlock_irq(&conf
->device_lock
);
1010 wake_up(&conf
->wait_barrier
);
1011 md_wakeup_thread(mddev
->thread
);
1016 /* we aren't scheduling, so we can do the write-out directly. */
1017 bio
= bio_list_get(&plug
->pending
);
1018 bitmap_unplug(mddev
->bitmap
);
1019 wake_up(&conf
->wait_barrier
);
1021 while (bio
) { /* submit pending writes */
1022 struct bio
*next
= bio
->bi_next
;
1023 bio
->bi_next
= NULL
;
1024 if (unlikely((bio
->bi_rw
& REQ_DISCARD
) &&
1025 !blk_queue_discard(bdev_get_queue(bio
->bi_bdev
))))
1026 /* Just ignore it */
1029 generic_make_request(bio
);
1035 static void raid1_make_request(struct mddev
*mddev
, struct bio
* bio
)
1037 struct r1conf
*conf
= mddev
->private;
1038 struct raid1_info
*mirror
;
1039 struct r1bio
*r1_bio
;
1040 struct bio
*read_bio
;
1042 struct bitmap
*bitmap
;
1043 unsigned long flags
;
1044 const int rw
= bio_data_dir(bio
);
1045 const unsigned long do_sync
= (bio
->bi_rw
& REQ_SYNC
);
1046 const unsigned long do_flush_fua
= (bio
->bi_rw
& (REQ_FLUSH
| REQ_FUA
));
1047 const unsigned long do_discard
= (bio
->bi_rw
1048 & (REQ_DISCARD
| REQ_SECURE
));
1049 const unsigned long do_same
= (bio
->bi_rw
& REQ_WRITE_SAME
);
1050 struct md_rdev
*blocked_rdev
;
1051 struct blk_plug_cb
*cb
;
1052 struct raid1_plug_cb
*plug
= NULL
;
1054 int sectors_handled
;
1056 sector_t start_next_window
;
1059 * Register the new request and wait if the reconstruction
1060 * thread has put up a bar for new requests.
1061 * Continue immediately if no resync is active currently.
1064 md_write_start(mddev
, bio
); /* wait on superblock update early */
1066 if (bio_data_dir(bio
) == WRITE
&&
1067 ((bio_end_sector(bio
) > mddev
->suspend_lo
&&
1068 bio
->bi_iter
.bi_sector
< mddev
->suspend_hi
) ||
1069 (mddev_is_clustered(mddev
) &&
1070 md_cluster_ops
->area_resyncing(mddev
, WRITE
,
1071 bio
->bi_iter
.bi_sector
, bio_end_sector(bio
))))) {
1072 /* As the suspend_* range is controlled by
1073 * userspace, we want an interruptible
1078 flush_signals(current
);
1079 prepare_to_wait(&conf
->wait_barrier
,
1080 &w
, TASK_INTERRUPTIBLE
);
1081 if (bio_end_sector(bio
) <= mddev
->suspend_lo
||
1082 bio
->bi_iter
.bi_sector
>= mddev
->suspend_hi
||
1083 (mddev_is_clustered(mddev
) &&
1084 !md_cluster_ops
->area_resyncing(mddev
, WRITE
,
1085 bio
->bi_iter
.bi_sector
, bio_end_sector(bio
))))
1089 finish_wait(&conf
->wait_barrier
, &w
);
1092 start_next_window
= wait_barrier(conf
, bio
);
1094 bitmap
= mddev
->bitmap
;
1097 * make_request() can abort the operation when READA is being
1098 * used and no empty request is available.
1101 r1_bio
= mempool_alloc(conf
->r1bio_pool
, GFP_NOIO
);
1103 r1_bio
->master_bio
= bio
;
1104 r1_bio
->sectors
= bio_sectors(bio
);
1106 r1_bio
->mddev
= mddev
;
1107 r1_bio
->sector
= bio
->bi_iter
.bi_sector
;
1109 /* We might need to issue multiple reads to different
1110 * devices if there are bad blocks around, so we keep
1111 * track of the number of reads in bio->bi_phys_segments.
1112 * If this is 0, there is only one r1_bio and no locking
1113 * will be needed when requests complete. If it is
1114 * non-zero, then it is the number of not-completed requests.
1116 bio
->bi_phys_segments
= 0;
1117 bio_clear_flag(bio
, BIO_SEG_VALID
);
1121 * read balancing logic:
1126 rdisk
= read_balance(conf
, r1_bio
, &max_sectors
);
1129 /* couldn't find anywhere to read from */
1130 raid_end_bio_io(r1_bio
);
1133 mirror
= conf
->mirrors
+ rdisk
;
1135 if (test_bit(WriteMostly
, &mirror
->rdev
->flags
) &&
1137 /* Reading from a write-mostly device must
1138 * take care not to over-take any writes
1141 wait_event(bitmap
->behind_wait
,
1142 atomic_read(&bitmap
->behind_writes
) == 0);
1144 r1_bio
->read_disk
= rdisk
;
1145 r1_bio
->start_next_window
= 0;
1147 read_bio
= bio_clone_mddev(bio
, GFP_NOIO
, mddev
);
1148 bio_trim(read_bio
, r1_bio
->sector
- bio
->bi_iter
.bi_sector
,
1151 r1_bio
->bios
[rdisk
] = read_bio
;
1153 read_bio
->bi_iter
.bi_sector
= r1_bio
->sector
+
1154 mirror
->rdev
->data_offset
;
1155 read_bio
->bi_bdev
= mirror
->rdev
->bdev
;
1156 read_bio
->bi_end_io
= raid1_end_read_request
;
1157 read_bio
->bi_rw
= READ
| do_sync
;
1158 read_bio
->bi_private
= r1_bio
;
1160 if (max_sectors
< r1_bio
->sectors
) {
1161 /* could not read all from this device, so we will
1162 * need another r1_bio.
1165 sectors_handled
= (r1_bio
->sector
+ max_sectors
1166 - bio
->bi_iter
.bi_sector
);
1167 r1_bio
->sectors
= max_sectors
;
1168 spin_lock_irq(&conf
->device_lock
);
1169 if (bio
->bi_phys_segments
== 0)
1170 bio
->bi_phys_segments
= 2;
1172 bio
->bi_phys_segments
++;
1173 spin_unlock_irq(&conf
->device_lock
);
1174 /* Cannot call generic_make_request directly
1175 * as that will be queued in __make_request
1176 * and subsequent mempool_alloc might block waiting
1177 * for it. So hand bio over to raid1d.
1179 reschedule_retry(r1_bio
);
1181 r1_bio
= mempool_alloc(conf
->r1bio_pool
, GFP_NOIO
);
1183 r1_bio
->master_bio
= bio
;
1184 r1_bio
->sectors
= bio_sectors(bio
) - sectors_handled
;
1186 r1_bio
->mddev
= mddev
;
1187 r1_bio
->sector
= bio
->bi_iter
.bi_sector
+
1191 generic_make_request(read_bio
);
1198 if (conf
->pending_count
>= max_queued_requests
) {
1199 md_wakeup_thread(mddev
->thread
);
1200 wait_event(conf
->wait_barrier
,
1201 conf
->pending_count
< max_queued_requests
);
1203 /* first select target devices under rcu_lock and
1204 * inc refcount on their rdev. Record them by setting
1206 * If there are known/acknowledged bad blocks on any device on
1207 * which we have seen a write error, we want to avoid writing those
1209 * This potentially requires several writes to write around
1210 * the bad blocks. Each set of writes gets it's own r1bio
1211 * with a set of bios attached.
1214 disks
= conf
->raid_disks
* 2;
1216 r1_bio
->start_next_window
= start_next_window
;
1217 blocked_rdev
= NULL
;
1219 max_sectors
= r1_bio
->sectors
;
1220 for (i
= 0; i
< disks
; i
++) {
1221 struct md_rdev
*rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
1222 if (rdev
&& unlikely(test_bit(Blocked
, &rdev
->flags
))) {
1223 atomic_inc(&rdev
->nr_pending
);
1224 blocked_rdev
= rdev
;
1227 r1_bio
->bios
[i
] = NULL
;
1228 if (!rdev
|| test_bit(Faulty
, &rdev
->flags
)) {
1229 if (i
< conf
->raid_disks
)
1230 set_bit(R1BIO_Degraded
, &r1_bio
->state
);
1234 atomic_inc(&rdev
->nr_pending
);
1235 if (test_bit(WriteErrorSeen
, &rdev
->flags
)) {
1240 is_bad
= is_badblock(rdev
, r1_bio
->sector
,
1242 &first_bad
, &bad_sectors
);
1244 /* mustn't write here until the bad block is
1246 set_bit(BlockedBadBlocks
, &rdev
->flags
);
1247 blocked_rdev
= rdev
;
1250 if (is_bad
&& first_bad
<= r1_bio
->sector
) {
1251 /* Cannot write here at all */
1252 bad_sectors
-= (r1_bio
->sector
- first_bad
);
1253 if (bad_sectors
< max_sectors
)
1254 /* mustn't write more than bad_sectors
1255 * to other devices yet
1257 max_sectors
= bad_sectors
;
1258 rdev_dec_pending(rdev
, mddev
);
1259 /* We don't set R1BIO_Degraded as that
1260 * only applies if the disk is
1261 * missing, so it might be re-added,
1262 * and we want to know to recover this
1264 * In this case the device is here,
1265 * and the fact that this chunk is not
1266 * in-sync is recorded in the bad
1272 int good_sectors
= first_bad
- r1_bio
->sector
;
1273 if (good_sectors
< max_sectors
)
1274 max_sectors
= good_sectors
;
1277 r1_bio
->bios
[i
] = bio
;
1281 if (unlikely(blocked_rdev
)) {
1282 /* Wait for this device to become unblocked */
1284 sector_t old
= start_next_window
;
1286 for (j
= 0; j
< i
; j
++)
1287 if (r1_bio
->bios
[j
])
1288 rdev_dec_pending(conf
->mirrors
[j
].rdev
, mddev
);
1290 allow_barrier(conf
, start_next_window
, bio
->bi_iter
.bi_sector
);
1291 md_wait_for_blocked_rdev(blocked_rdev
, mddev
);
1292 start_next_window
= wait_barrier(conf
, bio
);
1294 * We must make sure the multi r1bios of bio have
1295 * the same value of bi_phys_segments
1297 if (bio
->bi_phys_segments
&& old
&&
1298 old
!= start_next_window
)
1299 /* Wait for the former r1bio(s) to complete */
1300 wait_event(conf
->wait_barrier
,
1301 bio
->bi_phys_segments
== 1);
1305 if (max_sectors
< r1_bio
->sectors
) {
1306 /* We are splitting this write into multiple parts, so
1307 * we need to prepare for allocating another r1_bio.
1309 r1_bio
->sectors
= max_sectors
;
1310 spin_lock_irq(&conf
->device_lock
);
1311 if (bio
->bi_phys_segments
== 0)
1312 bio
->bi_phys_segments
= 2;
1314 bio
->bi_phys_segments
++;
1315 spin_unlock_irq(&conf
->device_lock
);
1317 sectors_handled
= r1_bio
->sector
+ max_sectors
- bio
->bi_iter
.bi_sector
;
1319 atomic_set(&r1_bio
->remaining
, 1);
1320 atomic_set(&r1_bio
->behind_remaining
, 0);
1323 for (i
= 0; i
< disks
; i
++) {
1325 if (!r1_bio
->bios
[i
])
1328 mbio
= bio_clone_mddev(bio
, GFP_NOIO
, mddev
);
1329 bio_trim(mbio
, r1_bio
->sector
- bio
->bi_iter
.bi_sector
, max_sectors
);
1333 * Not if there are too many, or cannot
1334 * allocate memory, or a reader on WriteMostly
1335 * is waiting for behind writes to flush */
1337 (atomic_read(&bitmap
->behind_writes
)
1338 < mddev
->bitmap_info
.max_write_behind
) &&
1339 !waitqueue_active(&bitmap
->behind_wait
))
1340 alloc_behind_pages(mbio
, r1_bio
);
1342 bitmap_startwrite(bitmap
, r1_bio
->sector
,
1344 test_bit(R1BIO_BehindIO
,
1348 if (r1_bio
->behind_bvecs
) {
1349 struct bio_vec
*bvec
;
1353 * We trimmed the bio, so _all is legit
1355 bio_for_each_segment_all(bvec
, mbio
, j
)
1356 bvec
->bv_page
= r1_bio
->behind_bvecs
[j
].bv_page
;
1357 if (test_bit(WriteMostly
, &conf
->mirrors
[i
].rdev
->flags
))
1358 atomic_inc(&r1_bio
->behind_remaining
);
1361 r1_bio
->bios
[i
] = mbio
;
1363 mbio
->bi_iter
.bi_sector
= (r1_bio
->sector
+
1364 conf
->mirrors
[i
].rdev
->data_offset
);
1365 mbio
->bi_bdev
= conf
->mirrors
[i
].rdev
->bdev
;
1366 mbio
->bi_end_io
= raid1_end_write_request
;
1368 WRITE
| do_flush_fua
| do_sync
| do_discard
| do_same
;
1369 mbio
->bi_private
= r1_bio
;
1371 atomic_inc(&r1_bio
->remaining
);
1373 cb
= blk_check_plugged(raid1_unplug
, mddev
, sizeof(*plug
));
1375 plug
= container_of(cb
, struct raid1_plug_cb
, cb
);
1378 spin_lock_irqsave(&conf
->device_lock
, flags
);
1380 bio_list_add(&plug
->pending
, mbio
);
1381 plug
->pending_cnt
++;
1383 bio_list_add(&conf
->pending_bio_list
, mbio
);
1384 conf
->pending_count
++;
1386 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
1388 md_wakeup_thread(mddev
->thread
);
1390 /* Mustn't call r1_bio_write_done before this next test,
1391 * as it could result in the bio being freed.
1393 if (sectors_handled
< bio_sectors(bio
)) {
1394 r1_bio_write_done(r1_bio
);
1395 /* We need another r1_bio. It has already been counted
1396 * in bio->bi_phys_segments
1398 r1_bio
= mempool_alloc(conf
->r1bio_pool
, GFP_NOIO
);
1399 r1_bio
->master_bio
= bio
;
1400 r1_bio
->sectors
= bio_sectors(bio
) - sectors_handled
;
1402 r1_bio
->mddev
= mddev
;
1403 r1_bio
->sector
= bio
->bi_iter
.bi_sector
+ sectors_handled
;
1407 r1_bio_write_done(r1_bio
);
1409 /* In case raid1d snuck in to freeze_array */
1410 wake_up(&conf
->wait_barrier
);
1413 static void raid1_status(struct seq_file
*seq
, struct mddev
*mddev
)
1415 struct r1conf
*conf
= mddev
->private;
1418 seq_printf(seq
, " [%d/%d] [", conf
->raid_disks
,
1419 conf
->raid_disks
- mddev
->degraded
);
1421 for (i
= 0; i
< conf
->raid_disks
; i
++) {
1422 struct md_rdev
*rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
1423 seq_printf(seq
, "%s",
1424 rdev
&& test_bit(In_sync
, &rdev
->flags
) ? "U" : "_");
1427 seq_printf(seq
, "]");
1430 static void raid1_error(struct mddev
*mddev
, struct md_rdev
*rdev
)
1432 char b
[BDEVNAME_SIZE
];
1433 struct r1conf
*conf
= mddev
->private;
1434 unsigned long flags
;
1437 * If it is not operational, then we have already marked it as dead
1438 * else if it is the last working disks, ignore the error, let the
1439 * next level up know.
1440 * else mark the drive as failed
1442 if (test_bit(In_sync
, &rdev
->flags
)
1443 && (conf
->raid_disks
- mddev
->degraded
) == 1) {
1445 * Don't fail the drive, act as though we were just a
1446 * normal single drive.
1447 * However don't try a recovery from this drive as
1448 * it is very likely to fail.
1450 conf
->recovery_disabled
= mddev
->recovery_disabled
;
1453 set_bit(Blocked
, &rdev
->flags
);
1454 spin_lock_irqsave(&conf
->device_lock
, flags
);
1455 if (test_and_clear_bit(In_sync
, &rdev
->flags
)) {
1457 set_bit(Faulty
, &rdev
->flags
);
1459 set_bit(Faulty
, &rdev
->flags
);
1460 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
1462 * if recovery is running, make sure it aborts.
1464 set_bit(MD_RECOVERY_INTR
, &mddev
->recovery
);
1465 set_mask_bits(&mddev
->flags
, 0,
1466 BIT(MD_CHANGE_DEVS
) | BIT(MD_CHANGE_PENDING
));
1468 "md/raid1:%s: Disk failure on %s, disabling device.\n"
1469 "md/raid1:%s: Operation continuing on %d devices.\n",
1470 mdname(mddev
), bdevname(rdev
->bdev
, b
),
1471 mdname(mddev
), conf
->raid_disks
- mddev
->degraded
);
1474 static void print_conf(struct r1conf
*conf
)
1478 printk(KERN_DEBUG
"RAID1 conf printout:\n");
1480 printk(KERN_DEBUG
"(!conf)\n");
1483 printk(KERN_DEBUG
" --- wd:%d rd:%d\n", conf
->raid_disks
- conf
->mddev
->degraded
,
1487 for (i
= 0; i
< conf
->raid_disks
; i
++) {
1488 char b
[BDEVNAME_SIZE
];
1489 struct md_rdev
*rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
1491 printk(KERN_DEBUG
" disk %d, wo:%d, o:%d, dev:%s\n",
1492 i
, !test_bit(In_sync
, &rdev
->flags
),
1493 !test_bit(Faulty
, &rdev
->flags
),
1494 bdevname(rdev
->bdev
,b
));
1499 static void close_sync(struct r1conf
*conf
)
1501 wait_barrier(conf
, NULL
);
1502 allow_barrier(conf
, 0, 0);
1504 mempool_destroy(conf
->r1buf_pool
);
1505 conf
->r1buf_pool
= NULL
;
1507 spin_lock_irq(&conf
->resync_lock
);
1508 conf
->next_resync
= MaxSector
- 2 * NEXT_NORMALIO_DISTANCE
;
1509 conf
->start_next_window
= MaxSector
;
1510 conf
->current_window_requests
+=
1511 conf
->next_window_requests
;
1512 conf
->next_window_requests
= 0;
1513 spin_unlock_irq(&conf
->resync_lock
);
1516 static int raid1_spare_active(struct mddev
*mddev
)
1519 struct r1conf
*conf
= mddev
->private;
1521 unsigned long flags
;
1524 * Find all failed disks within the RAID1 configuration
1525 * and mark them readable.
1526 * Called under mddev lock, so rcu protection not needed.
1527 * device_lock used to avoid races with raid1_end_read_request
1528 * which expects 'In_sync' flags and ->degraded to be consistent.
1530 spin_lock_irqsave(&conf
->device_lock
, flags
);
1531 for (i
= 0; i
< conf
->raid_disks
; i
++) {
1532 struct md_rdev
*rdev
= conf
->mirrors
[i
].rdev
;
1533 struct md_rdev
*repl
= conf
->mirrors
[conf
->raid_disks
+ i
].rdev
;
1535 && !test_bit(Candidate
, &repl
->flags
)
1536 && repl
->recovery_offset
== MaxSector
1537 && !test_bit(Faulty
, &repl
->flags
)
1538 && !test_and_set_bit(In_sync
, &repl
->flags
)) {
1539 /* replacement has just become active */
1541 !test_and_clear_bit(In_sync
, &rdev
->flags
))
1544 /* Replaced device not technically
1545 * faulty, but we need to be sure
1546 * it gets removed and never re-added
1548 set_bit(Faulty
, &rdev
->flags
);
1549 sysfs_notify_dirent_safe(
1554 && rdev
->recovery_offset
== MaxSector
1555 && !test_bit(Faulty
, &rdev
->flags
)
1556 && !test_and_set_bit(In_sync
, &rdev
->flags
)) {
1558 sysfs_notify_dirent_safe(rdev
->sysfs_state
);
1561 mddev
->degraded
-= count
;
1562 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
1568 static int raid1_add_disk(struct mddev
*mddev
, struct md_rdev
*rdev
)
1570 struct r1conf
*conf
= mddev
->private;
1573 struct raid1_info
*p
;
1575 int last
= conf
->raid_disks
- 1;
1577 if (mddev
->recovery_disabled
== conf
->recovery_disabled
)
1580 if (md_integrity_add_rdev(rdev
, mddev
))
1583 if (rdev
->raid_disk
>= 0)
1584 first
= last
= rdev
->raid_disk
;
1587 * find the disk ... but prefer rdev->saved_raid_disk
1590 if (rdev
->saved_raid_disk
>= 0 &&
1591 rdev
->saved_raid_disk
>= first
&&
1592 conf
->mirrors
[rdev
->saved_raid_disk
].rdev
== NULL
)
1593 first
= last
= rdev
->saved_raid_disk
;
1595 for (mirror
= first
; mirror
<= last
; mirror
++) {
1596 p
= conf
->mirrors
+mirror
;
1600 disk_stack_limits(mddev
->gendisk
, rdev
->bdev
,
1601 rdev
->data_offset
<< 9);
1603 p
->head_position
= 0;
1604 rdev
->raid_disk
= mirror
;
1606 /* As all devices are equivalent, we don't need a full recovery
1607 * if this was recently any drive of the array
1609 if (rdev
->saved_raid_disk
< 0)
1611 rcu_assign_pointer(p
->rdev
, rdev
);
1614 if (test_bit(WantReplacement
, &p
->rdev
->flags
) &&
1615 p
[conf
->raid_disks
].rdev
== NULL
) {
1616 /* Add this device as a replacement */
1617 clear_bit(In_sync
, &rdev
->flags
);
1618 set_bit(Replacement
, &rdev
->flags
);
1619 rdev
->raid_disk
= mirror
;
1622 rcu_assign_pointer(p
[conf
->raid_disks
].rdev
, rdev
);
1626 if (mddev
->queue
&& blk_queue_discard(bdev_get_queue(rdev
->bdev
)))
1627 queue_flag_set_unlocked(QUEUE_FLAG_DISCARD
, mddev
->queue
);
1632 static int raid1_remove_disk(struct mddev
*mddev
, struct md_rdev
*rdev
)
1634 struct r1conf
*conf
= mddev
->private;
1636 int number
= rdev
->raid_disk
;
1637 struct raid1_info
*p
= conf
->mirrors
+ number
;
1639 if (rdev
!= p
->rdev
)
1640 p
= conf
->mirrors
+ conf
->raid_disks
+ number
;
1643 if (rdev
== p
->rdev
) {
1644 if (test_bit(In_sync
, &rdev
->flags
) ||
1645 atomic_read(&rdev
->nr_pending
)) {
1649 /* Only remove non-faulty devices if recovery
1652 if (!test_bit(Faulty
, &rdev
->flags
) &&
1653 mddev
->recovery_disabled
!= conf
->recovery_disabled
&&
1654 mddev
->degraded
< conf
->raid_disks
) {
1659 if (!test_bit(RemoveSynchronized
, &rdev
->flags
)) {
1661 if (atomic_read(&rdev
->nr_pending
)) {
1662 /* lost the race, try later */
1668 if (conf
->mirrors
[conf
->raid_disks
+ number
].rdev
) {
1669 /* We just removed a device that is being replaced.
1670 * Move down the replacement. We drain all IO before
1671 * doing this to avoid confusion.
1673 struct md_rdev
*repl
=
1674 conf
->mirrors
[conf
->raid_disks
+ number
].rdev
;
1675 freeze_array(conf
, 0);
1676 clear_bit(Replacement
, &repl
->flags
);
1678 conf
->mirrors
[conf
->raid_disks
+ number
].rdev
= NULL
;
1679 unfreeze_array(conf
);
1680 clear_bit(WantReplacement
, &rdev
->flags
);
1682 clear_bit(WantReplacement
, &rdev
->flags
);
1683 err
= md_integrity_register(mddev
);
1691 static void end_sync_read(struct bio
*bio
)
1693 struct r1bio
*r1_bio
= bio
->bi_private
;
1695 update_head_pos(r1_bio
->read_disk
, r1_bio
);
1698 * we have read a block, now it needs to be re-written,
1699 * or re-read if the read failed.
1700 * We don't do much here, just schedule handling by raid1d
1703 set_bit(R1BIO_Uptodate
, &r1_bio
->state
);
1705 if (atomic_dec_and_test(&r1_bio
->remaining
))
1706 reschedule_retry(r1_bio
);
1709 static void end_sync_write(struct bio
*bio
)
1711 int uptodate
= !bio
->bi_error
;
1712 struct r1bio
*r1_bio
= bio
->bi_private
;
1713 struct mddev
*mddev
= r1_bio
->mddev
;
1714 struct r1conf
*conf
= mddev
->private;
1717 struct md_rdev
*rdev
= conf
->mirrors
[find_bio_disk(r1_bio
, bio
)].rdev
;
1720 sector_t sync_blocks
= 0;
1721 sector_t s
= r1_bio
->sector
;
1722 long sectors_to_go
= r1_bio
->sectors
;
1723 /* make sure these bits doesn't get cleared. */
1725 bitmap_end_sync(mddev
->bitmap
, s
,
1728 sectors_to_go
-= sync_blocks
;
1729 } while (sectors_to_go
> 0);
1730 set_bit(WriteErrorSeen
, &rdev
->flags
);
1731 if (!test_and_set_bit(WantReplacement
, &rdev
->flags
))
1732 set_bit(MD_RECOVERY_NEEDED
, &
1734 set_bit(R1BIO_WriteError
, &r1_bio
->state
);
1735 } else if (is_badblock(rdev
, r1_bio
->sector
, r1_bio
->sectors
,
1736 &first_bad
, &bad_sectors
) &&
1737 !is_badblock(conf
->mirrors
[r1_bio
->read_disk
].rdev
,
1740 &first_bad
, &bad_sectors
)
1742 set_bit(R1BIO_MadeGood
, &r1_bio
->state
);
1744 if (atomic_dec_and_test(&r1_bio
->remaining
)) {
1745 int s
= r1_bio
->sectors
;
1746 if (test_bit(R1BIO_MadeGood
, &r1_bio
->state
) ||
1747 test_bit(R1BIO_WriteError
, &r1_bio
->state
))
1748 reschedule_retry(r1_bio
);
1751 md_done_sync(mddev
, s
, uptodate
);
1756 static int r1_sync_page_io(struct md_rdev
*rdev
, sector_t sector
,
1757 int sectors
, struct page
*page
, int rw
)
1759 if (sync_page_io(rdev
, sector
, sectors
<< 9, page
, rw
, false))
1763 set_bit(WriteErrorSeen
, &rdev
->flags
);
1764 if (!test_and_set_bit(WantReplacement
,
1766 set_bit(MD_RECOVERY_NEEDED
, &
1767 rdev
->mddev
->recovery
);
1769 /* need to record an error - either for the block or the device */
1770 if (!rdev_set_badblocks(rdev
, sector
, sectors
, 0))
1771 md_error(rdev
->mddev
, rdev
);
1775 static int fix_sync_read_error(struct r1bio
*r1_bio
)
1777 /* Try some synchronous reads of other devices to get
1778 * good data, much like with normal read errors. Only
1779 * read into the pages we already have so we don't
1780 * need to re-issue the read request.
1781 * We don't need to freeze the array, because being in an
1782 * active sync request, there is no normal IO, and
1783 * no overlapping syncs.
1784 * We don't need to check is_badblock() again as we
1785 * made sure that anything with a bad block in range
1786 * will have bi_end_io clear.
1788 struct mddev
*mddev
= r1_bio
->mddev
;
1789 struct r1conf
*conf
= mddev
->private;
1790 struct bio
*bio
= r1_bio
->bios
[r1_bio
->read_disk
];
1791 sector_t sect
= r1_bio
->sector
;
1792 int sectors
= r1_bio
->sectors
;
1797 int d
= r1_bio
->read_disk
;
1799 struct md_rdev
*rdev
;
1802 if (s
> (PAGE_SIZE
>>9))
1805 if (r1_bio
->bios
[d
]->bi_end_io
== end_sync_read
) {
1806 /* No rcu protection needed here devices
1807 * can only be removed when no resync is
1808 * active, and resync is currently active
1810 rdev
= conf
->mirrors
[d
].rdev
;
1811 if (sync_page_io(rdev
, sect
, s
<<9,
1812 bio
->bi_io_vec
[idx
].bv_page
,
1819 if (d
== conf
->raid_disks
* 2)
1821 } while (!success
&& d
!= r1_bio
->read_disk
);
1824 char b
[BDEVNAME_SIZE
];
1826 /* Cannot read from anywhere, this block is lost.
1827 * Record a bad block on each device. If that doesn't
1828 * work just disable and interrupt the recovery.
1829 * Don't fail devices as that won't really help.
1831 printk(KERN_ALERT
"md/raid1:%s: %s: unrecoverable I/O read error"
1832 " for block %llu\n",
1834 bdevname(bio
->bi_bdev
, b
),
1835 (unsigned long long)r1_bio
->sector
);
1836 for (d
= 0; d
< conf
->raid_disks
* 2; d
++) {
1837 rdev
= conf
->mirrors
[d
].rdev
;
1838 if (!rdev
|| test_bit(Faulty
, &rdev
->flags
))
1840 if (!rdev_set_badblocks(rdev
, sect
, s
, 0))
1844 conf
->recovery_disabled
=
1845 mddev
->recovery_disabled
;
1846 set_bit(MD_RECOVERY_INTR
, &mddev
->recovery
);
1847 md_done_sync(mddev
, r1_bio
->sectors
, 0);
1859 /* write it back and re-read */
1860 while (d
!= r1_bio
->read_disk
) {
1862 d
= conf
->raid_disks
* 2;
1864 if (r1_bio
->bios
[d
]->bi_end_io
!= end_sync_read
)
1866 rdev
= conf
->mirrors
[d
].rdev
;
1867 if (r1_sync_page_io(rdev
, sect
, s
,
1868 bio
->bi_io_vec
[idx
].bv_page
,
1870 r1_bio
->bios
[d
]->bi_end_io
= NULL
;
1871 rdev_dec_pending(rdev
, mddev
);
1875 while (d
!= r1_bio
->read_disk
) {
1877 d
= conf
->raid_disks
* 2;
1879 if (r1_bio
->bios
[d
]->bi_end_io
!= end_sync_read
)
1881 rdev
= conf
->mirrors
[d
].rdev
;
1882 if (r1_sync_page_io(rdev
, sect
, s
,
1883 bio
->bi_io_vec
[idx
].bv_page
,
1885 atomic_add(s
, &rdev
->corrected_errors
);
1891 set_bit(R1BIO_Uptodate
, &r1_bio
->state
);
1896 static void process_checks(struct r1bio
*r1_bio
)
1898 /* We have read all readable devices. If we haven't
1899 * got the block, then there is no hope left.
1900 * If we have, then we want to do a comparison
1901 * and skip the write if everything is the same.
1902 * If any blocks failed to read, then we need to
1903 * attempt an over-write
1905 struct mddev
*mddev
= r1_bio
->mddev
;
1906 struct r1conf
*conf
= mddev
->private;
1911 /* Fix variable parts of all bios */
1912 vcnt
= (r1_bio
->sectors
+ PAGE_SIZE
/ 512 - 1) >> (PAGE_SHIFT
- 9);
1913 for (i
= 0; i
< conf
->raid_disks
* 2; i
++) {
1917 struct bio
*b
= r1_bio
->bios
[i
];
1918 if (b
->bi_end_io
!= end_sync_read
)
1920 /* fixup the bio for reuse, but preserve errno */
1921 error
= b
->bi_error
;
1923 b
->bi_error
= error
;
1925 b
->bi_iter
.bi_size
= r1_bio
->sectors
<< 9;
1926 b
->bi_iter
.bi_sector
= r1_bio
->sector
+
1927 conf
->mirrors
[i
].rdev
->data_offset
;
1928 b
->bi_bdev
= conf
->mirrors
[i
].rdev
->bdev
;
1929 b
->bi_end_io
= end_sync_read
;
1930 b
->bi_private
= r1_bio
;
1932 size
= b
->bi_iter
.bi_size
;
1933 for (j
= 0; j
< vcnt
; j
++) {
1935 bi
= &b
->bi_io_vec
[j
];
1937 if (size
> PAGE_SIZE
)
1938 bi
->bv_len
= PAGE_SIZE
;
1944 for (primary
= 0; primary
< conf
->raid_disks
* 2; primary
++)
1945 if (r1_bio
->bios
[primary
]->bi_end_io
== end_sync_read
&&
1946 !r1_bio
->bios
[primary
]->bi_error
) {
1947 r1_bio
->bios
[primary
]->bi_end_io
= NULL
;
1948 rdev_dec_pending(conf
->mirrors
[primary
].rdev
, mddev
);
1951 r1_bio
->read_disk
= primary
;
1952 for (i
= 0; i
< conf
->raid_disks
* 2; i
++) {
1954 struct bio
*pbio
= r1_bio
->bios
[primary
];
1955 struct bio
*sbio
= r1_bio
->bios
[i
];
1956 int error
= sbio
->bi_error
;
1958 if (sbio
->bi_end_io
!= end_sync_read
)
1960 /* Now we can 'fixup' the error value */
1964 for (j
= vcnt
; j
-- ; ) {
1966 p
= pbio
->bi_io_vec
[j
].bv_page
;
1967 s
= sbio
->bi_io_vec
[j
].bv_page
;
1968 if (memcmp(page_address(p
),
1970 sbio
->bi_io_vec
[j
].bv_len
))
1976 atomic64_add(r1_bio
->sectors
, &mddev
->resync_mismatches
);
1977 if (j
< 0 || (test_bit(MD_RECOVERY_CHECK
, &mddev
->recovery
)
1979 /* No need to write to this device. */
1980 sbio
->bi_end_io
= NULL
;
1981 rdev_dec_pending(conf
->mirrors
[i
].rdev
, mddev
);
1985 bio_copy_data(sbio
, pbio
);
1989 static void sync_request_write(struct mddev
*mddev
, struct r1bio
*r1_bio
)
1991 struct r1conf
*conf
= mddev
->private;
1993 int disks
= conf
->raid_disks
* 2;
1994 struct bio
*bio
, *wbio
;
1996 bio
= r1_bio
->bios
[r1_bio
->read_disk
];
1998 if (!test_bit(R1BIO_Uptodate
, &r1_bio
->state
))
1999 /* ouch - failed to read all of that. */
2000 if (!fix_sync_read_error(r1_bio
))
2003 if (test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
))
2004 process_checks(r1_bio
);
2009 atomic_set(&r1_bio
->remaining
, 1);
2010 for (i
= 0; i
< disks
; i
++) {
2011 wbio
= r1_bio
->bios
[i
];
2012 if (wbio
->bi_end_io
== NULL
||
2013 (wbio
->bi_end_io
== end_sync_read
&&
2014 (i
== r1_bio
->read_disk
||
2015 !test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
))))
2018 wbio
->bi_rw
= WRITE
;
2019 wbio
->bi_end_io
= end_sync_write
;
2020 atomic_inc(&r1_bio
->remaining
);
2021 md_sync_acct(conf
->mirrors
[i
].rdev
->bdev
, bio_sectors(wbio
));
2023 generic_make_request(wbio
);
2026 if (atomic_dec_and_test(&r1_bio
->remaining
)) {
2027 /* if we're here, all write(s) have completed, so clean up */
2028 int s
= r1_bio
->sectors
;
2029 if (test_bit(R1BIO_MadeGood
, &r1_bio
->state
) ||
2030 test_bit(R1BIO_WriteError
, &r1_bio
->state
))
2031 reschedule_retry(r1_bio
);
2034 md_done_sync(mddev
, s
, 1);
2040 * This is a kernel thread which:
2042 * 1. Retries failed read operations on working mirrors.
2043 * 2. Updates the raid superblock when problems encounter.
2044 * 3. Performs writes following reads for array synchronising.
2047 static void fix_read_error(struct r1conf
*conf
, int read_disk
,
2048 sector_t sect
, int sectors
)
2050 struct mddev
*mddev
= conf
->mddev
;
2056 struct md_rdev
*rdev
;
2058 if (s
> (PAGE_SIZE
>>9))
2066 rdev
= rcu_dereference(conf
->mirrors
[d
].rdev
);
2068 (test_bit(In_sync
, &rdev
->flags
) ||
2069 (!test_bit(Faulty
, &rdev
->flags
) &&
2070 rdev
->recovery_offset
>= sect
+ s
)) &&
2071 is_badblock(rdev
, sect
, s
,
2072 &first_bad
, &bad_sectors
) == 0) {
2073 atomic_inc(&rdev
->nr_pending
);
2075 if (sync_page_io(rdev
, sect
, s
<<9,
2076 conf
->tmppage
, READ
, false))
2078 rdev_dec_pending(rdev
, mddev
);
2084 if (d
== conf
->raid_disks
* 2)
2086 } while (!success
&& d
!= read_disk
);
2089 /* Cannot read from anywhere - mark it bad */
2090 struct md_rdev
*rdev
= conf
->mirrors
[read_disk
].rdev
;
2091 if (!rdev_set_badblocks(rdev
, sect
, s
, 0))
2092 md_error(mddev
, rdev
);
2095 /* write it back and re-read */
2097 while (d
!= read_disk
) {
2099 d
= conf
->raid_disks
* 2;
2102 rdev
= rcu_dereference(conf
->mirrors
[d
].rdev
);
2104 !test_bit(Faulty
, &rdev
->flags
)) {
2105 atomic_inc(&rdev
->nr_pending
);
2107 r1_sync_page_io(rdev
, sect
, s
,
2108 conf
->tmppage
, WRITE
);
2109 rdev_dec_pending(rdev
, mddev
);
2114 while (d
!= read_disk
) {
2115 char b
[BDEVNAME_SIZE
];
2117 d
= conf
->raid_disks
* 2;
2120 rdev
= rcu_dereference(conf
->mirrors
[d
].rdev
);
2122 !test_bit(Faulty
, &rdev
->flags
)) {
2123 atomic_inc(&rdev
->nr_pending
);
2125 if (r1_sync_page_io(rdev
, sect
, s
,
2126 conf
->tmppage
, READ
)) {
2127 atomic_add(s
, &rdev
->corrected_errors
);
2129 "md/raid1:%s: read error corrected "
2130 "(%d sectors at %llu on %s)\n",
2132 (unsigned long long)(sect
+
2134 bdevname(rdev
->bdev
, b
));
2136 rdev_dec_pending(rdev
, mddev
);
2145 static int narrow_write_error(struct r1bio
*r1_bio
, int i
)
2147 struct mddev
*mddev
= r1_bio
->mddev
;
2148 struct r1conf
*conf
= mddev
->private;
2149 struct md_rdev
*rdev
= conf
->mirrors
[i
].rdev
;
2151 /* bio has the data to be written to device 'i' where
2152 * we just recently had a write error.
2153 * We repeatedly clone the bio and trim down to one block,
2154 * then try the write. Where the write fails we record
2156 * It is conceivable that the bio doesn't exactly align with
2157 * blocks. We must handle this somehow.
2159 * We currently own a reference on the rdev.
2165 int sect_to_write
= r1_bio
->sectors
;
2168 if (rdev
->badblocks
.shift
< 0)
2171 block_sectors
= roundup(1 << rdev
->badblocks
.shift
,
2172 bdev_logical_block_size(rdev
->bdev
) >> 9);
2173 sector
= r1_bio
->sector
;
2174 sectors
= ((sector
+ block_sectors
)
2175 & ~(sector_t
)(block_sectors
- 1))
2178 while (sect_to_write
) {
2180 if (sectors
> sect_to_write
)
2181 sectors
= sect_to_write
;
2182 /* Write at 'sector' for 'sectors'*/
2184 if (test_bit(R1BIO_BehindIO
, &r1_bio
->state
)) {
2185 unsigned vcnt
= r1_bio
->behind_page_count
;
2186 struct bio_vec
*vec
= r1_bio
->behind_bvecs
;
2188 while (!vec
->bv_page
) {
2193 wbio
= bio_alloc_mddev(GFP_NOIO
, vcnt
, mddev
);
2194 memcpy(wbio
->bi_io_vec
, vec
, vcnt
* sizeof(struct bio_vec
));
2196 wbio
->bi_vcnt
= vcnt
;
2198 wbio
= bio_clone_mddev(r1_bio
->master_bio
, GFP_NOIO
, mddev
);
2201 wbio
->bi_rw
= WRITE
;
2202 wbio
->bi_iter
.bi_sector
= r1_bio
->sector
;
2203 wbio
->bi_iter
.bi_size
= r1_bio
->sectors
<< 9;
2205 bio_trim(wbio
, sector
- r1_bio
->sector
, sectors
);
2206 wbio
->bi_iter
.bi_sector
+= rdev
->data_offset
;
2207 wbio
->bi_bdev
= rdev
->bdev
;
2208 if (submit_bio_wait(WRITE
, wbio
) < 0)
2210 ok
= rdev_set_badblocks(rdev
, sector
,
2215 sect_to_write
-= sectors
;
2217 sectors
= block_sectors
;
2222 static void handle_sync_write_finished(struct r1conf
*conf
, struct r1bio
*r1_bio
)
2225 int s
= r1_bio
->sectors
;
2226 for (m
= 0; m
< conf
->raid_disks
* 2 ; m
++) {
2227 struct md_rdev
*rdev
= conf
->mirrors
[m
].rdev
;
2228 struct bio
*bio
= r1_bio
->bios
[m
];
2229 if (bio
->bi_end_io
== NULL
)
2231 if (!bio
->bi_error
&&
2232 test_bit(R1BIO_MadeGood
, &r1_bio
->state
)) {
2233 rdev_clear_badblocks(rdev
, r1_bio
->sector
, s
, 0);
2235 if (bio
->bi_error
&&
2236 test_bit(R1BIO_WriteError
, &r1_bio
->state
)) {
2237 if (!rdev_set_badblocks(rdev
, r1_bio
->sector
, s
, 0))
2238 md_error(conf
->mddev
, rdev
);
2242 md_done_sync(conf
->mddev
, s
, 1);
2245 static void handle_write_finished(struct r1conf
*conf
, struct r1bio
*r1_bio
)
2249 for (m
= 0; m
< conf
->raid_disks
* 2 ; m
++)
2250 if (r1_bio
->bios
[m
] == IO_MADE_GOOD
) {
2251 struct md_rdev
*rdev
= conf
->mirrors
[m
].rdev
;
2252 rdev_clear_badblocks(rdev
,
2254 r1_bio
->sectors
, 0);
2255 rdev_dec_pending(rdev
, conf
->mddev
);
2256 } else if (r1_bio
->bios
[m
] != NULL
) {
2257 /* This drive got a write error. We need to
2258 * narrow down and record precise write
2262 if (!narrow_write_error(r1_bio
, m
)) {
2263 md_error(conf
->mddev
,
2264 conf
->mirrors
[m
].rdev
);
2265 /* an I/O failed, we can't clear the bitmap */
2266 set_bit(R1BIO_Degraded
, &r1_bio
->state
);
2268 rdev_dec_pending(conf
->mirrors
[m
].rdev
,
2272 spin_lock_irq(&conf
->device_lock
);
2273 list_add(&r1_bio
->retry_list
, &conf
->bio_end_io_list
);
2275 spin_unlock_irq(&conf
->device_lock
);
2276 md_wakeup_thread(conf
->mddev
->thread
);
2278 if (test_bit(R1BIO_WriteError
, &r1_bio
->state
))
2279 close_write(r1_bio
);
2280 raid_end_bio_io(r1_bio
);
2284 static void handle_read_error(struct r1conf
*conf
, struct r1bio
*r1_bio
)
2288 struct mddev
*mddev
= conf
->mddev
;
2290 char b
[BDEVNAME_SIZE
];
2291 struct md_rdev
*rdev
;
2293 clear_bit(R1BIO_ReadError
, &r1_bio
->state
);
2294 /* we got a read error. Maybe the drive is bad. Maybe just
2295 * the block and we can fix it.
2296 * We freeze all other IO, and try reading the block from
2297 * other devices. When we find one, we re-write
2298 * and check it that fixes the read error.
2299 * This is all done synchronously while the array is
2302 if (mddev
->ro
== 0) {
2303 freeze_array(conf
, 1);
2304 fix_read_error(conf
, r1_bio
->read_disk
,
2305 r1_bio
->sector
, r1_bio
->sectors
);
2306 unfreeze_array(conf
);
2308 md_error(mddev
, conf
->mirrors
[r1_bio
->read_disk
].rdev
);
2309 rdev_dec_pending(conf
->mirrors
[r1_bio
->read_disk
].rdev
, conf
->mddev
);
2311 bio
= r1_bio
->bios
[r1_bio
->read_disk
];
2312 bdevname(bio
->bi_bdev
, b
);
2314 disk
= read_balance(conf
, r1_bio
, &max_sectors
);
2316 printk(KERN_ALERT
"md/raid1:%s: %s: unrecoverable I/O"
2317 " read error for block %llu\n",
2318 mdname(mddev
), b
, (unsigned long long)r1_bio
->sector
);
2319 raid_end_bio_io(r1_bio
);
2321 const unsigned long do_sync
2322 = r1_bio
->master_bio
->bi_rw
& REQ_SYNC
;
2324 r1_bio
->bios
[r1_bio
->read_disk
] =
2325 mddev
->ro
? IO_BLOCKED
: NULL
;
2328 r1_bio
->read_disk
= disk
;
2329 bio
= bio_clone_mddev(r1_bio
->master_bio
, GFP_NOIO
, mddev
);
2330 bio_trim(bio
, r1_bio
->sector
- bio
->bi_iter
.bi_sector
,
2332 r1_bio
->bios
[r1_bio
->read_disk
] = bio
;
2333 rdev
= conf
->mirrors
[disk
].rdev
;
2334 printk_ratelimited(KERN_ERR
2335 "md/raid1:%s: redirecting sector %llu"
2336 " to other mirror: %s\n",
2338 (unsigned long long)r1_bio
->sector
,
2339 bdevname(rdev
->bdev
, b
));
2340 bio
->bi_iter
.bi_sector
= r1_bio
->sector
+ rdev
->data_offset
;
2341 bio
->bi_bdev
= rdev
->bdev
;
2342 bio
->bi_end_io
= raid1_end_read_request
;
2343 bio
->bi_rw
= READ
| do_sync
;
2344 bio
->bi_private
= r1_bio
;
2345 if (max_sectors
< r1_bio
->sectors
) {
2346 /* Drat - have to split this up more */
2347 struct bio
*mbio
= r1_bio
->master_bio
;
2348 int sectors_handled
= (r1_bio
->sector
+ max_sectors
2349 - mbio
->bi_iter
.bi_sector
);
2350 r1_bio
->sectors
= max_sectors
;
2351 spin_lock_irq(&conf
->device_lock
);
2352 if (mbio
->bi_phys_segments
== 0)
2353 mbio
->bi_phys_segments
= 2;
2355 mbio
->bi_phys_segments
++;
2356 spin_unlock_irq(&conf
->device_lock
);
2357 generic_make_request(bio
);
2360 r1_bio
= mempool_alloc(conf
->r1bio_pool
, GFP_NOIO
);
2362 r1_bio
->master_bio
= mbio
;
2363 r1_bio
->sectors
= bio_sectors(mbio
) - sectors_handled
;
2365 set_bit(R1BIO_ReadError
, &r1_bio
->state
);
2366 r1_bio
->mddev
= mddev
;
2367 r1_bio
->sector
= mbio
->bi_iter
.bi_sector
+
2372 generic_make_request(bio
);
2376 static void raid1d(struct md_thread
*thread
)
2378 struct mddev
*mddev
= thread
->mddev
;
2379 struct r1bio
*r1_bio
;
2380 unsigned long flags
;
2381 struct r1conf
*conf
= mddev
->private;
2382 struct list_head
*head
= &conf
->retry_list
;
2383 struct blk_plug plug
;
2385 md_check_recovery(mddev
);
2387 if (!list_empty_careful(&conf
->bio_end_io_list
) &&
2388 !test_bit(MD_CHANGE_PENDING
, &mddev
->flags
)) {
2390 spin_lock_irqsave(&conf
->device_lock
, flags
);
2391 if (!test_bit(MD_CHANGE_PENDING
, &mddev
->flags
)) {
2392 while (!list_empty(&conf
->bio_end_io_list
)) {
2393 list_move(conf
->bio_end_io_list
.prev
, &tmp
);
2397 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
2398 while (!list_empty(&tmp
)) {
2399 r1_bio
= list_first_entry(&tmp
, struct r1bio
,
2401 list_del(&r1_bio
->retry_list
);
2402 if (mddev
->degraded
)
2403 set_bit(R1BIO_Degraded
, &r1_bio
->state
);
2404 if (test_bit(R1BIO_WriteError
, &r1_bio
->state
))
2405 close_write(r1_bio
);
2406 raid_end_bio_io(r1_bio
);
2410 blk_start_plug(&plug
);
2413 flush_pending_writes(conf
);
2415 spin_lock_irqsave(&conf
->device_lock
, flags
);
2416 if (list_empty(head
)) {
2417 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
2420 r1_bio
= list_entry(head
->prev
, struct r1bio
, retry_list
);
2421 list_del(head
->prev
);
2423 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
2425 mddev
= r1_bio
->mddev
;
2426 conf
= mddev
->private;
2427 if (test_bit(R1BIO_IsSync
, &r1_bio
->state
)) {
2428 if (test_bit(R1BIO_MadeGood
, &r1_bio
->state
) ||
2429 test_bit(R1BIO_WriteError
, &r1_bio
->state
))
2430 handle_sync_write_finished(conf
, r1_bio
);
2432 sync_request_write(mddev
, r1_bio
);
2433 } else if (test_bit(R1BIO_MadeGood
, &r1_bio
->state
) ||
2434 test_bit(R1BIO_WriteError
, &r1_bio
->state
))
2435 handle_write_finished(conf
, r1_bio
);
2436 else if (test_bit(R1BIO_ReadError
, &r1_bio
->state
))
2437 handle_read_error(conf
, r1_bio
);
2439 /* just a partial read to be scheduled from separate
2442 generic_make_request(r1_bio
->bios
[r1_bio
->read_disk
]);
2445 if (mddev
->flags
& ~(1<<MD_CHANGE_PENDING
))
2446 md_check_recovery(mddev
);
2448 blk_finish_plug(&plug
);
2451 static int init_resync(struct r1conf
*conf
)
2455 buffs
= RESYNC_WINDOW
/ RESYNC_BLOCK_SIZE
;
2456 BUG_ON(conf
->r1buf_pool
);
2457 conf
->r1buf_pool
= mempool_create(buffs
, r1buf_pool_alloc
, r1buf_pool_free
,
2459 if (!conf
->r1buf_pool
)
2461 conf
->next_resync
= 0;
2466 * perform a "sync" on one "block"
2468 * We need to make sure that no normal I/O request - particularly write
2469 * requests - conflict with active sync requests.
2471 * This is achieved by tracking pending requests and a 'barrier' concept
2472 * that can be installed to exclude normal IO requests.
2475 static sector_t
raid1_sync_request(struct mddev
*mddev
, sector_t sector_nr
,
2478 struct r1conf
*conf
= mddev
->private;
2479 struct r1bio
*r1_bio
;
2481 sector_t max_sector
, nr_sectors
;
2485 int write_targets
= 0, read_targets
= 0;
2486 sector_t sync_blocks
;
2487 int still_degraded
= 0;
2488 int good_sectors
= RESYNC_SECTORS
;
2489 int min_bad
= 0; /* number of sectors that are bad in all devices */
2491 if (!conf
->r1buf_pool
)
2492 if (init_resync(conf
))
2495 max_sector
= mddev
->dev_sectors
;
2496 if (sector_nr
>= max_sector
) {
2497 /* If we aborted, we need to abort the
2498 * sync on the 'current' bitmap chunk (there will
2499 * only be one in raid1 resync.
2500 * We can find the current addess in mddev->curr_resync
2502 if (mddev
->curr_resync
< max_sector
) /* aborted */
2503 bitmap_end_sync(mddev
->bitmap
, mddev
->curr_resync
,
2505 else /* completed sync */
2508 bitmap_close_sync(mddev
->bitmap
);
2511 if (mddev_is_clustered(mddev
)) {
2512 conf
->cluster_sync_low
= 0;
2513 conf
->cluster_sync_high
= 0;
2518 if (mddev
->bitmap
== NULL
&&
2519 mddev
->recovery_cp
== MaxSector
&&
2520 !test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
) &&
2521 conf
->fullsync
== 0) {
2523 return max_sector
- sector_nr
;
2525 /* before building a request, check if we can skip these blocks..
2526 * This call the bitmap_start_sync doesn't actually record anything
2528 if (!bitmap_start_sync(mddev
->bitmap
, sector_nr
, &sync_blocks
, 1) &&
2529 !conf
->fullsync
&& !test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
)) {
2530 /* We can skip this block, and probably several more */
2536 * If there is non-resync activity waiting for a turn, then let it
2537 * though before starting on this new sync request.
2539 if (conf
->nr_waiting
)
2540 schedule_timeout_uninterruptible(1);
2542 /* we are incrementing sector_nr below. To be safe, we check against
2543 * sector_nr + two times RESYNC_SECTORS
2546 bitmap_cond_end_sync(mddev
->bitmap
, sector_nr
,
2547 mddev_is_clustered(mddev
) && (sector_nr
+ 2 * RESYNC_SECTORS
> conf
->cluster_sync_high
));
2548 r1_bio
= mempool_alloc(conf
->r1buf_pool
, GFP_NOIO
);
2550 raise_barrier(conf
, sector_nr
);
2554 * If we get a correctably read error during resync or recovery,
2555 * we might want to read from a different device. So we
2556 * flag all drives that could conceivably be read from for READ,
2557 * and any others (which will be non-In_sync devices) for WRITE.
2558 * If a read fails, we try reading from something else for which READ
2562 r1_bio
->mddev
= mddev
;
2563 r1_bio
->sector
= sector_nr
;
2565 set_bit(R1BIO_IsSync
, &r1_bio
->state
);
2567 for (i
= 0; i
< conf
->raid_disks
* 2; i
++) {
2568 struct md_rdev
*rdev
;
2569 bio
= r1_bio
->bios
[i
];
2572 rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
2574 test_bit(Faulty
, &rdev
->flags
)) {
2575 if (i
< conf
->raid_disks
)
2577 } else if (!test_bit(In_sync
, &rdev
->flags
)) {
2579 bio
->bi_end_io
= end_sync_write
;
2582 /* may need to read from here */
2583 sector_t first_bad
= MaxSector
;
2586 if (is_badblock(rdev
, sector_nr
, good_sectors
,
2587 &first_bad
, &bad_sectors
)) {
2588 if (first_bad
> sector_nr
)
2589 good_sectors
= first_bad
- sector_nr
;
2591 bad_sectors
-= (sector_nr
- first_bad
);
2593 min_bad
> bad_sectors
)
2594 min_bad
= bad_sectors
;
2597 if (sector_nr
< first_bad
) {
2598 if (test_bit(WriteMostly
, &rdev
->flags
)) {
2606 bio
->bi_end_io
= end_sync_read
;
2608 } else if (!test_bit(WriteErrorSeen
, &rdev
->flags
) &&
2609 test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
) &&
2610 !test_bit(MD_RECOVERY_CHECK
, &mddev
->recovery
)) {
2612 * The device is suitable for reading (InSync),
2613 * but has bad block(s) here. Let's try to correct them,
2614 * if we are doing resync or repair. Otherwise, leave
2615 * this device alone for this sync request.
2618 bio
->bi_end_io
= end_sync_write
;
2622 if (bio
->bi_end_io
) {
2623 atomic_inc(&rdev
->nr_pending
);
2624 bio
->bi_iter
.bi_sector
= sector_nr
+ rdev
->data_offset
;
2625 bio
->bi_bdev
= rdev
->bdev
;
2626 bio
->bi_private
= r1_bio
;
2632 r1_bio
->read_disk
= disk
;
2634 if (read_targets
== 0 && min_bad
> 0) {
2635 /* These sectors are bad on all InSync devices, so we
2636 * need to mark them bad on all write targets
2639 for (i
= 0 ; i
< conf
->raid_disks
* 2 ; i
++)
2640 if (r1_bio
->bios
[i
]->bi_end_io
== end_sync_write
) {
2641 struct md_rdev
*rdev
= conf
->mirrors
[i
].rdev
;
2642 ok
= rdev_set_badblocks(rdev
, sector_nr
,
2646 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
2651 /* Cannot record the badblocks, so need to
2653 * If there are multiple read targets, could just
2654 * fail the really bad ones ???
2656 conf
->recovery_disabled
= mddev
->recovery_disabled
;
2657 set_bit(MD_RECOVERY_INTR
, &mddev
->recovery
);
2663 if (min_bad
> 0 && min_bad
< good_sectors
) {
2664 /* only resync enough to reach the next bad->good
2666 good_sectors
= min_bad
;
2669 if (test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
) && read_targets
> 0)
2670 /* extra read targets are also write targets */
2671 write_targets
+= read_targets
-1;
2673 if (write_targets
== 0 || read_targets
== 0) {
2674 /* There is nowhere to write, so all non-sync
2675 * drives must be failed - so we are finished
2679 max_sector
= sector_nr
+ min_bad
;
2680 rv
= max_sector
- sector_nr
;
2686 if (max_sector
> mddev
->resync_max
)
2687 max_sector
= mddev
->resync_max
; /* Don't do IO beyond here */
2688 if (max_sector
> sector_nr
+ good_sectors
)
2689 max_sector
= sector_nr
+ good_sectors
;
2694 int len
= PAGE_SIZE
;
2695 if (sector_nr
+ (len
>>9) > max_sector
)
2696 len
= (max_sector
- sector_nr
) << 9;
2699 if (sync_blocks
== 0) {
2700 if (!bitmap_start_sync(mddev
->bitmap
, sector_nr
,
2701 &sync_blocks
, still_degraded
) &&
2703 !test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
))
2705 if ((len
>> 9) > sync_blocks
)
2706 len
= sync_blocks
<<9;
2709 for (i
= 0 ; i
< conf
->raid_disks
* 2; i
++) {
2710 bio
= r1_bio
->bios
[i
];
2711 if (bio
->bi_end_io
) {
2712 page
= bio
->bi_io_vec
[bio
->bi_vcnt
].bv_page
;
2713 if (bio_add_page(bio
, page
, len
, 0) == 0) {
2715 bio
->bi_io_vec
[bio
->bi_vcnt
].bv_page
= page
;
2718 bio
= r1_bio
->bios
[i
];
2719 if (bio
->bi_end_io
==NULL
)
2721 /* remove last page from this bio */
2723 bio
->bi_iter
.bi_size
-= len
;
2724 bio_clear_flag(bio
, BIO_SEG_VALID
);
2730 nr_sectors
+= len
>>9;
2731 sector_nr
+= len
>>9;
2732 sync_blocks
-= (len
>>9);
2733 } while (r1_bio
->bios
[disk
]->bi_vcnt
< RESYNC_PAGES
);
2735 r1_bio
->sectors
= nr_sectors
;
2737 if (mddev_is_clustered(mddev
) &&
2738 conf
->cluster_sync_high
< sector_nr
+ nr_sectors
) {
2739 conf
->cluster_sync_low
= mddev
->curr_resync_completed
;
2740 conf
->cluster_sync_high
= conf
->cluster_sync_low
+ CLUSTER_RESYNC_WINDOW_SECTORS
;
2741 /* Send resync message */
2742 md_cluster_ops
->resync_info_update(mddev
,
2743 conf
->cluster_sync_low
,
2744 conf
->cluster_sync_high
);
2747 /* For a user-requested sync, we read all readable devices and do a
2750 if (test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
)) {
2751 atomic_set(&r1_bio
->remaining
, read_targets
);
2752 for (i
= 0; i
< conf
->raid_disks
* 2 && read_targets
; i
++) {
2753 bio
= r1_bio
->bios
[i
];
2754 if (bio
->bi_end_io
== end_sync_read
) {
2756 md_sync_acct(bio
->bi_bdev
, nr_sectors
);
2757 generic_make_request(bio
);
2761 atomic_set(&r1_bio
->remaining
, 1);
2762 bio
= r1_bio
->bios
[r1_bio
->read_disk
];
2763 md_sync_acct(bio
->bi_bdev
, nr_sectors
);
2764 generic_make_request(bio
);
2770 static sector_t
raid1_size(struct mddev
*mddev
, sector_t sectors
, int raid_disks
)
2775 return mddev
->dev_sectors
;
2778 static struct r1conf
*setup_conf(struct mddev
*mddev
)
2780 struct r1conf
*conf
;
2782 struct raid1_info
*disk
;
2783 struct md_rdev
*rdev
;
2786 conf
= kzalloc(sizeof(struct r1conf
), GFP_KERNEL
);
2790 conf
->mirrors
= kzalloc(sizeof(struct raid1_info
)
2791 * mddev
->raid_disks
* 2,
2796 conf
->tmppage
= alloc_page(GFP_KERNEL
);
2800 conf
->poolinfo
= kzalloc(sizeof(*conf
->poolinfo
), GFP_KERNEL
);
2801 if (!conf
->poolinfo
)
2803 conf
->poolinfo
->raid_disks
= mddev
->raid_disks
* 2;
2804 conf
->r1bio_pool
= mempool_create(NR_RAID1_BIOS
, r1bio_pool_alloc
,
2807 if (!conf
->r1bio_pool
)
2810 conf
->poolinfo
->mddev
= mddev
;
2813 spin_lock_init(&conf
->device_lock
);
2814 rdev_for_each(rdev
, mddev
) {
2815 struct request_queue
*q
;
2816 int disk_idx
= rdev
->raid_disk
;
2817 if (disk_idx
>= mddev
->raid_disks
2820 if (test_bit(Replacement
, &rdev
->flags
))
2821 disk
= conf
->mirrors
+ mddev
->raid_disks
+ disk_idx
;
2823 disk
= conf
->mirrors
+ disk_idx
;
2828 q
= bdev_get_queue(rdev
->bdev
);
2830 disk
->head_position
= 0;
2831 disk
->seq_start
= MaxSector
;
2833 conf
->raid_disks
= mddev
->raid_disks
;
2834 conf
->mddev
= mddev
;
2835 INIT_LIST_HEAD(&conf
->retry_list
);
2836 INIT_LIST_HEAD(&conf
->bio_end_io_list
);
2838 spin_lock_init(&conf
->resync_lock
);
2839 init_waitqueue_head(&conf
->wait_barrier
);
2841 bio_list_init(&conf
->pending_bio_list
);
2842 conf
->pending_count
= 0;
2843 conf
->recovery_disabled
= mddev
->recovery_disabled
- 1;
2845 conf
->start_next_window
= MaxSector
;
2846 conf
->current_window_requests
= conf
->next_window_requests
= 0;
2849 for (i
= 0; i
< conf
->raid_disks
* 2; i
++) {
2851 disk
= conf
->mirrors
+ i
;
2853 if (i
< conf
->raid_disks
&&
2854 disk
[conf
->raid_disks
].rdev
) {
2855 /* This slot has a replacement. */
2857 /* No original, just make the replacement
2858 * a recovering spare
2861 disk
[conf
->raid_disks
].rdev
;
2862 disk
[conf
->raid_disks
].rdev
= NULL
;
2863 } else if (!test_bit(In_sync
, &disk
->rdev
->flags
))
2864 /* Original is not in_sync - bad */
2869 !test_bit(In_sync
, &disk
->rdev
->flags
)) {
2870 disk
->head_position
= 0;
2872 (disk
->rdev
->saved_raid_disk
< 0))
2878 conf
->thread
= md_register_thread(raid1d
, mddev
, "raid1");
2879 if (!conf
->thread
) {
2881 "md/raid1:%s: couldn't allocate thread\n",
2890 mempool_destroy(conf
->r1bio_pool
);
2891 kfree(conf
->mirrors
);
2892 safe_put_page(conf
->tmppage
);
2893 kfree(conf
->poolinfo
);
2896 return ERR_PTR(err
);
2899 static void raid1_free(struct mddev
*mddev
, void *priv
);
2900 static int raid1_run(struct mddev
*mddev
)
2902 struct r1conf
*conf
;
2904 struct md_rdev
*rdev
;
2906 bool discard_supported
= false;
2908 if (mddev
->level
!= 1) {
2909 printk(KERN_ERR
"md/raid1:%s: raid level not set to mirroring (%d)\n",
2910 mdname(mddev
), mddev
->level
);
2913 if (mddev
->reshape_position
!= MaxSector
) {
2914 printk(KERN_ERR
"md/raid1:%s: reshape_position set but not supported\n",
2919 * copy the already verified devices into our private RAID1
2920 * bookkeeping area. [whatever we allocate in run(),
2921 * should be freed in raid1_free()]
2923 if (mddev
->private == NULL
)
2924 conf
= setup_conf(mddev
);
2926 conf
= mddev
->private;
2929 return PTR_ERR(conf
);
2932 blk_queue_max_write_same_sectors(mddev
->queue
, 0);
2934 rdev_for_each(rdev
, mddev
) {
2935 if (!mddev
->gendisk
)
2937 disk_stack_limits(mddev
->gendisk
, rdev
->bdev
,
2938 rdev
->data_offset
<< 9);
2939 if (blk_queue_discard(bdev_get_queue(rdev
->bdev
)))
2940 discard_supported
= true;
2943 mddev
->degraded
= 0;
2944 for (i
=0; i
< conf
->raid_disks
; i
++)
2945 if (conf
->mirrors
[i
].rdev
== NULL
||
2946 !test_bit(In_sync
, &conf
->mirrors
[i
].rdev
->flags
) ||
2947 test_bit(Faulty
, &conf
->mirrors
[i
].rdev
->flags
))
2950 if (conf
->raid_disks
- mddev
->degraded
== 1)
2951 mddev
->recovery_cp
= MaxSector
;
2953 if (mddev
->recovery_cp
!= MaxSector
)
2954 printk(KERN_NOTICE
"md/raid1:%s: not clean"
2955 " -- starting background reconstruction\n",
2958 "md/raid1:%s: active with %d out of %d mirrors\n",
2959 mdname(mddev
), mddev
->raid_disks
- mddev
->degraded
,
2963 * Ok, everything is just fine now
2965 mddev
->thread
= conf
->thread
;
2966 conf
->thread
= NULL
;
2967 mddev
->private = conf
;
2969 md_set_array_sectors(mddev
, raid1_size(mddev
, 0, 0));
2972 if (discard_supported
)
2973 queue_flag_set_unlocked(QUEUE_FLAG_DISCARD
,
2976 queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD
,
2980 ret
= md_integrity_register(mddev
);
2982 md_unregister_thread(&mddev
->thread
);
2983 raid1_free(mddev
, conf
);
2988 static void raid1_free(struct mddev
*mddev
, void *priv
)
2990 struct r1conf
*conf
= priv
;
2992 mempool_destroy(conf
->r1bio_pool
);
2993 kfree(conf
->mirrors
);
2994 safe_put_page(conf
->tmppage
);
2995 kfree(conf
->poolinfo
);
2999 static int raid1_resize(struct mddev
*mddev
, sector_t sectors
)
3001 /* no resync is happening, and there is enough space
3002 * on all devices, so we can resize.
3003 * We need to make sure resync covers any new space.
3004 * If the array is shrinking we should possibly wait until
3005 * any io in the removed space completes, but it hardly seems
3008 sector_t newsize
= raid1_size(mddev
, sectors
, 0);
3009 if (mddev
->external_size
&&
3010 mddev
->array_sectors
> newsize
)
3012 if (mddev
->bitmap
) {
3013 int ret
= bitmap_resize(mddev
->bitmap
, newsize
, 0, 0);
3017 md_set_array_sectors(mddev
, newsize
);
3018 set_capacity(mddev
->gendisk
, mddev
->array_sectors
);
3019 revalidate_disk(mddev
->gendisk
);
3020 if (sectors
> mddev
->dev_sectors
&&
3021 mddev
->recovery_cp
> mddev
->dev_sectors
) {
3022 mddev
->recovery_cp
= mddev
->dev_sectors
;
3023 set_bit(MD_RECOVERY_NEEDED
, &mddev
->recovery
);
3025 mddev
->dev_sectors
= sectors
;
3026 mddev
->resync_max_sectors
= sectors
;
3030 static int raid1_reshape(struct mddev
*mddev
)
3033 * 1/ resize the r1bio_pool
3034 * 2/ resize conf->mirrors
3036 * We allocate a new r1bio_pool if we can.
3037 * Then raise a device barrier and wait until all IO stops.
3038 * Then resize conf->mirrors and swap in the new r1bio pool.
3040 * At the same time, we "pack" the devices so that all the missing
3041 * devices have the higher raid_disk numbers.
3043 mempool_t
*newpool
, *oldpool
;
3044 struct pool_info
*newpoolinfo
;
3045 struct raid1_info
*newmirrors
;
3046 struct r1conf
*conf
= mddev
->private;
3047 int cnt
, raid_disks
;
3048 unsigned long flags
;
3051 /* Cannot change chunk_size, layout, or level */
3052 if (mddev
->chunk_sectors
!= mddev
->new_chunk_sectors
||
3053 mddev
->layout
!= mddev
->new_layout
||
3054 mddev
->level
!= mddev
->new_level
) {
3055 mddev
->new_chunk_sectors
= mddev
->chunk_sectors
;
3056 mddev
->new_layout
= mddev
->layout
;
3057 mddev
->new_level
= mddev
->level
;
3061 if (!mddev_is_clustered(mddev
)) {
3062 err
= md_allow_write(mddev
);
3067 raid_disks
= mddev
->raid_disks
+ mddev
->delta_disks
;
3069 if (raid_disks
< conf
->raid_disks
) {
3071 for (d
= 0; d
< conf
->raid_disks
; d
++)
3072 if (conf
->mirrors
[d
].rdev
)
3074 if (cnt
> raid_disks
)
3078 newpoolinfo
= kmalloc(sizeof(*newpoolinfo
), GFP_KERNEL
);
3081 newpoolinfo
->mddev
= mddev
;
3082 newpoolinfo
->raid_disks
= raid_disks
* 2;
3084 newpool
= mempool_create(NR_RAID1_BIOS
, r1bio_pool_alloc
,
3085 r1bio_pool_free
, newpoolinfo
);
3090 newmirrors
= kzalloc(sizeof(struct raid1_info
) * raid_disks
* 2,
3094 mempool_destroy(newpool
);
3098 freeze_array(conf
, 0);
3100 /* ok, everything is stopped */
3101 oldpool
= conf
->r1bio_pool
;
3102 conf
->r1bio_pool
= newpool
;
3104 for (d
= d2
= 0; d
< conf
->raid_disks
; d
++) {
3105 struct md_rdev
*rdev
= conf
->mirrors
[d
].rdev
;
3106 if (rdev
&& rdev
->raid_disk
!= d2
) {
3107 sysfs_unlink_rdev(mddev
, rdev
);
3108 rdev
->raid_disk
= d2
;
3109 sysfs_unlink_rdev(mddev
, rdev
);
3110 if (sysfs_link_rdev(mddev
, rdev
))
3112 "md/raid1:%s: cannot register rd%d\n",
3113 mdname(mddev
), rdev
->raid_disk
);
3116 newmirrors
[d2
++].rdev
= rdev
;
3118 kfree(conf
->mirrors
);
3119 conf
->mirrors
= newmirrors
;
3120 kfree(conf
->poolinfo
);
3121 conf
->poolinfo
= newpoolinfo
;
3123 spin_lock_irqsave(&conf
->device_lock
, flags
);
3124 mddev
->degraded
+= (raid_disks
- conf
->raid_disks
);
3125 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
3126 conf
->raid_disks
= mddev
->raid_disks
= raid_disks
;
3127 mddev
->delta_disks
= 0;
3129 unfreeze_array(conf
);
3131 set_bit(MD_RECOVERY_RECOVER
, &mddev
->recovery
);
3132 set_bit(MD_RECOVERY_NEEDED
, &mddev
->recovery
);
3133 md_wakeup_thread(mddev
->thread
);
3135 mempool_destroy(oldpool
);
3139 static void raid1_quiesce(struct mddev
*mddev
, int state
)
3141 struct r1conf
*conf
= mddev
->private;
3144 case 2: /* wake for suspend */
3145 wake_up(&conf
->wait_barrier
);
3148 freeze_array(conf
, 0);
3151 unfreeze_array(conf
);
3156 static void *raid1_takeover(struct mddev
*mddev
)
3158 /* raid1 can take over:
3159 * raid5 with 2 devices, any layout or chunk size
3161 if (mddev
->level
== 5 && mddev
->raid_disks
== 2) {
3162 struct r1conf
*conf
;
3163 mddev
->new_level
= 1;
3164 mddev
->new_layout
= 0;
3165 mddev
->new_chunk_sectors
= 0;
3166 conf
= setup_conf(mddev
);
3168 /* Array must appear to be quiesced */
3169 conf
->array_frozen
= 1;
3172 return ERR_PTR(-EINVAL
);
3175 static struct md_personality raid1_personality
=
3179 .owner
= THIS_MODULE
,
3180 .make_request
= raid1_make_request
,
3183 .status
= raid1_status
,
3184 .error_handler
= raid1_error
,
3185 .hot_add_disk
= raid1_add_disk
,
3186 .hot_remove_disk
= raid1_remove_disk
,
3187 .spare_active
= raid1_spare_active
,
3188 .sync_request
= raid1_sync_request
,
3189 .resize
= raid1_resize
,
3191 .check_reshape
= raid1_reshape
,
3192 .quiesce
= raid1_quiesce
,
3193 .takeover
= raid1_takeover
,
3194 .congested
= raid1_congested
,
3197 static int __init
raid_init(void)
3199 return register_md_personality(&raid1_personality
);
3202 static void raid_exit(void)
3204 unregister_md_personality(&raid1_personality
);
3207 module_init(raid_init
);
3208 module_exit(raid_exit
);
3209 MODULE_LICENSE("GPL");
3210 MODULE_DESCRIPTION("RAID1 (mirroring) personality for MD");
3211 MODULE_ALIAS("md-personality-3"); /* RAID1 */
3212 MODULE_ALIAS("md-raid1");
3213 MODULE_ALIAS("md-level-1");
3215 module_param(max_queued_requests
, int, S_IRUGO
|S_IWUSR
);