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 NEXT_NORMALIO_DISTANCE (3 * RESYNC_WINDOW_SECTORS)
95 static void * r1buf_pool_alloc(gfp_t gfp_flags
, void *data
)
97 struct pool_info
*pi
= data
;
103 r1_bio
= r1bio_pool_alloc(gfp_flags
, pi
);
108 * Allocate bios : 1 for reading, n-1 for writing
110 for (j
= pi
->raid_disks
; j
-- ; ) {
111 bio
= bio_kmalloc(gfp_flags
, RESYNC_PAGES
);
114 r1_bio
->bios
[j
] = bio
;
117 * Allocate RESYNC_PAGES data pages and attach them to
119 * If this is a user-requested check/repair, allocate
120 * RESYNC_PAGES for each bio.
122 if (test_bit(MD_RECOVERY_REQUESTED
, &pi
->mddev
->recovery
))
123 need_pages
= pi
->raid_disks
;
126 for (j
= 0; j
< need_pages
; j
++) {
127 bio
= r1_bio
->bios
[j
];
128 bio
->bi_vcnt
= RESYNC_PAGES
;
130 if (bio_alloc_pages(bio
, gfp_flags
))
133 /* If not user-requests, copy the page pointers to all bios */
134 if (!test_bit(MD_RECOVERY_REQUESTED
, &pi
->mddev
->recovery
)) {
135 for (i
=0; i
<RESYNC_PAGES
; i
++)
136 for (j
=1; j
<pi
->raid_disks
; j
++)
137 r1_bio
->bios
[j
]->bi_io_vec
[i
].bv_page
=
138 r1_bio
->bios
[0]->bi_io_vec
[i
].bv_page
;
141 r1_bio
->master_bio
= NULL
;
149 bio_for_each_segment_all(bv
, r1_bio
->bios
[j
], i
)
150 __free_page(bv
->bv_page
);
154 while (++j
< pi
->raid_disks
)
155 bio_put(r1_bio
->bios
[j
]);
156 r1bio_pool_free(r1_bio
, data
);
160 static void r1buf_pool_free(void *__r1_bio
, void *data
)
162 struct pool_info
*pi
= data
;
164 struct r1bio
*r1bio
= __r1_bio
;
166 for (i
= 0; i
< RESYNC_PAGES
; i
++)
167 for (j
= pi
->raid_disks
; j
-- ;) {
169 r1bio
->bios
[j
]->bi_io_vec
[i
].bv_page
!=
170 r1bio
->bios
[0]->bi_io_vec
[i
].bv_page
)
171 safe_put_page(r1bio
->bios
[j
]->bi_io_vec
[i
].bv_page
);
173 for (i
=0 ; i
< pi
->raid_disks
; i
++)
174 bio_put(r1bio
->bios
[i
]);
176 r1bio_pool_free(r1bio
, data
);
179 static void put_all_bios(struct r1conf
*conf
, struct r1bio
*r1_bio
)
183 for (i
= 0; i
< conf
->raid_disks
* 2; i
++) {
184 struct bio
**bio
= r1_bio
->bios
+ i
;
185 if (!BIO_SPECIAL(*bio
))
191 static void free_r1bio(struct r1bio
*r1_bio
)
193 struct r1conf
*conf
= r1_bio
->mddev
->private;
195 put_all_bios(conf
, r1_bio
);
196 mempool_free(r1_bio
, conf
->r1bio_pool
);
199 static void put_buf(struct r1bio
*r1_bio
)
201 struct r1conf
*conf
= r1_bio
->mddev
->private;
204 for (i
= 0; i
< conf
->raid_disks
* 2; i
++) {
205 struct bio
*bio
= r1_bio
->bios
[i
];
207 rdev_dec_pending(conf
->mirrors
[i
].rdev
, r1_bio
->mddev
);
210 mempool_free(r1_bio
, conf
->r1buf_pool
);
215 static void reschedule_retry(struct r1bio
*r1_bio
)
218 struct mddev
*mddev
= r1_bio
->mddev
;
219 struct r1conf
*conf
= mddev
->private;
221 spin_lock_irqsave(&conf
->device_lock
, flags
);
222 list_add(&r1_bio
->retry_list
, &conf
->retry_list
);
224 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
226 wake_up(&conf
->wait_barrier
);
227 md_wakeup_thread(mddev
->thread
);
231 * raid_end_bio_io() is called when we have finished servicing a mirrored
232 * operation and are ready to return a success/failure code to the buffer
235 static void call_bio_endio(struct r1bio
*r1_bio
)
237 struct bio
*bio
= r1_bio
->master_bio
;
239 struct r1conf
*conf
= r1_bio
->mddev
->private;
240 sector_t start_next_window
= r1_bio
->start_next_window
;
241 sector_t bi_sector
= bio
->bi_iter
.bi_sector
;
243 if (bio
->bi_phys_segments
) {
245 spin_lock_irqsave(&conf
->device_lock
, flags
);
246 bio
->bi_phys_segments
--;
247 done
= (bio
->bi_phys_segments
== 0);
248 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
250 * make_request() might be waiting for
251 * bi_phys_segments to decrease
253 wake_up(&conf
->wait_barrier
);
257 if (!test_bit(R1BIO_Uptodate
, &r1_bio
->state
))
258 clear_bit(BIO_UPTODATE
, &bio
->bi_flags
);
262 * Wake up any possible resync thread that waits for the device
265 allow_barrier(conf
, start_next_window
, bi_sector
);
269 static void raid_end_bio_io(struct r1bio
*r1_bio
)
271 struct bio
*bio
= r1_bio
->master_bio
;
273 /* if nobody has done the final endio yet, do it now */
274 if (!test_and_set_bit(R1BIO_Returned
, &r1_bio
->state
)) {
275 pr_debug("raid1: sync end %s on sectors %llu-%llu\n",
276 (bio_data_dir(bio
) == WRITE
) ? "write" : "read",
277 (unsigned long long) bio
->bi_iter
.bi_sector
,
278 (unsigned long long) bio_end_sector(bio
) - 1);
280 call_bio_endio(r1_bio
);
286 * Update disk head position estimator based on IRQ completion info.
288 static inline void update_head_pos(int disk
, struct r1bio
*r1_bio
)
290 struct r1conf
*conf
= r1_bio
->mddev
->private;
292 conf
->mirrors
[disk
].head_position
=
293 r1_bio
->sector
+ (r1_bio
->sectors
);
297 * Find the disk number which triggered given bio
299 static int find_bio_disk(struct r1bio
*r1_bio
, struct bio
*bio
)
302 struct r1conf
*conf
= r1_bio
->mddev
->private;
303 int raid_disks
= conf
->raid_disks
;
305 for (mirror
= 0; mirror
< raid_disks
* 2; mirror
++)
306 if (r1_bio
->bios
[mirror
] == bio
)
309 BUG_ON(mirror
== raid_disks
* 2);
310 update_head_pos(mirror
, r1_bio
);
315 static void raid1_end_read_request(struct bio
*bio
, int error
)
317 int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
318 struct r1bio
*r1_bio
= bio
->bi_private
;
320 struct r1conf
*conf
= r1_bio
->mddev
->private;
322 mirror
= r1_bio
->read_disk
;
324 * this branch is our 'one mirror IO has finished' event handler:
326 update_head_pos(mirror
, r1_bio
);
329 set_bit(R1BIO_Uptodate
, &r1_bio
->state
);
331 /* If all other devices have failed, we want to return
332 * the error upwards rather than fail the last device.
333 * Here we redefine "uptodate" to mean "Don't want to retry"
336 spin_lock_irqsave(&conf
->device_lock
, flags
);
337 if (r1_bio
->mddev
->degraded
== conf
->raid_disks
||
338 (r1_bio
->mddev
->degraded
== conf
->raid_disks
-1 &&
339 !test_bit(Faulty
, &conf
->mirrors
[mirror
].rdev
->flags
)))
341 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
345 raid_end_bio_io(r1_bio
);
346 rdev_dec_pending(conf
->mirrors
[mirror
].rdev
, conf
->mddev
);
351 char b
[BDEVNAME_SIZE
];
353 KERN_ERR
"md/raid1:%s: %s: "
354 "rescheduling sector %llu\n",
356 bdevname(conf
->mirrors
[mirror
].rdev
->bdev
,
358 (unsigned long long)r1_bio
->sector
);
359 set_bit(R1BIO_ReadError
, &r1_bio
->state
);
360 reschedule_retry(r1_bio
);
361 /* don't drop the reference on read_disk yet */
365 static void close_write(struct r1bio
*r1_bio
)
367 /* it really is the end of this request */
368 if (test_bit(R1BIO_BehindIO
, &r1_bio
->state
)) {
369 /* free extra copy of the data pages */
370 int i
= r1_bio
->behind_page_count
;
372 safe_put_page(r1_bio
->behind_bvecs
[i
].bv_page
);
373 kfree(r1_bio
->behind_bvecs
);
374 r1_bio
->behind_bvecs
= NULL
;
376 /* clear the bitmap if all writes complete successfully */
377 bitmap_endwrite(r1_bio
->mddev
->bitmap
, r1_bio
->sector
,
379 !test_bit(R1BIO_Degraded
, &r1_bio
->state
),
380 test_bit(R1BIO_BehindIO
, &r1_bio
->state
));
381 md_write_end(r1_bio
->mddev
);
384 static void r1_bio_write_done(struct r1bio
*r1_bio
)
386 if (!atomic_dec_and_test(&r1_bio
->remaining
))
389 if (test_bit(R1BIO_WriteError
, &r1_bio
->state
))
390 reschedule_retry(r1_bio
);
393 if (test_bit(R1BIO_MadeGood
, &r1_bio
->state
))
394 reschedule_retry(r1_bio
);
396 raid_end_bio_io(r1_bio
);
400 static void raid1_end_write_request(struct bio
*bio
, int error
)
402 int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
403 struct r1bio
*r1_bio
= bio
->bi_private
;
404 int mirror
, behind
= test_bit(R1BIO_BehindIO
, &r1_bio
->state
);
405 struct r1conf
*conf
= r1_bio
->mddev
->private;
406 struct bio
*to_put
= NULL
;
408 mirror
= find_bio_disk(r1_bio
, bio
);
411 * 'one mirror IO has finished' event handler:
414 set_bit(WriteErrorSeen
,
415 &conf
->mirrors
[mirror
].rdev
->flags
);
416 if (!test_and_set_bit(WantReplacement
,
417 &conf
->mirrors
[mirror
].rdev
->flags
))
418 set_bit(MD_RECOVERY_NEEDED
, &
419 conf
->mddev
->recovery
);
421 set_bit(R1BIO_WriteError
, &r1_bio
->state
);
424 * Set R1BIO_Uptodate in our master bio, so that we
425 * will return a good error code for to the higher
426 * levels even if IO on some other mirrored buffer
429 * The 'master' represents the composite IO operation
430 * to user-side. So if something waits for IO, then it
431 * will wait for the 'master' bio.
436 r1_bio
->bios
[mirror
] = NULL
;
439 * Do not set R1BIO_Uptodate if the current device is
440 * rebuilding or Faulty. This is because we cannot use
441 * such device for properly reading the data back (we could
442 * potentially use it, if the current write would have felt
443 * before rdev->recovery_offset, but for simplicity we don't
446 if (test_bit(In_sync
, &conf
->mirrors
[mirror
].rdev
->flags
) &&
447 !test_bit(Faulty
, &conf
->mirrors
[mirror
].rdev
->flags
))
448 set_bit(R1BIO_Uptodate
, &r1_bio
->state
);
450 /* Maybe we can clear some bad blocks. */
451 if (is_badblock(conf
->mirrors
[mirror
].rdev
,
452 r1_bio
->sector
, r1_bio
->sectors
,
453 &first_bad
, &bad_sectors
)) {
454 r1_bio
->bios
[mirror
] = IO_MADE_GOOD
;
455 set_bit(R1BIO_MadeGood
, &r1_bio
->state
);
460 if (test_bit(WriteMostly
, &conf
->mirrors
[mirror
].rdev
->flags
))
461 atomic_dec(&r1_bio
->behind_remaining
);
464 * In behind mode, we ACK the master bio once the I/O
465 * has safely reached all non-writemostly
466 * disks. Setting the Returned bit ensures that this
467 * gets done only once -- we don't ever want to return
468 * -EIO here, instead we'll wait
470 if (atomic_read(&r1_bio
->behind_remaining
) >= (atomic_read(&r1_bio
->remaining
)-1) &&
471 test_bit(R1BIO_Uptodate
, &r1_bio
->state
)) {
472 /* Maybe we can return now */
473 if (!test_and_set_bit(R1BIO_Returned
, &r1_bio
->state
)) {
474 struct bio
*mbio
= r1_bio
->master_bio
;
475 pr_debug("raid1: behind end write sectors"
477 (unsigned long long) mbio
->bi_iter
.bi_sector
,
478 (unsigned long long) bio_end_sector(mbio
) - 1);
479 call_bio_endio(r1_bio
);
483 if (r1_bio
->bios
[mirror
] == NULL
)
484 rdev_dec_pending(conf
->mirrors
[mirror
].rdev
,
488 * Let's see if all mirrored write operations have finished
491 r1_bio_write_done(r1_bio
);
498 * This routine returns the disk from which the requested read should
499 * be done. There is a per-array 'next expected sequential IO' sector
500 * number - if this matches on the next IO then we use the last disk.
501 * There is also a per-disk 'last know head position' sector that is
502 * maintained from IRQ contexts, both the normal and the resync IO
503 * completion handlers update this position correctly. If there is no
504 * perfect sequential match then we pick the disk whose head is closest.
506 * If there are 2 mirrors in the same 2 devices, performance degrades
507 * because position is mirror, not device based.
509 * The rdev for the device selected will have nr_pending incremented.
511 static int read_balance(struct r1conf
*conf
, struct r1bio
*r1_bio
, int *max_sectors
)
513 const sector_t this_sector
= r1_bio
->sector
;
515 int best_good_sectors
;
516 int best_disk
, best_dist_disk
, best_pending_disk
;
520 unsigned int min_pending
;
521 struct md_rdev
*rdev
;
523 int choose_next_idle
;
527 * Check if we can balance. We can balance on the whole
528 * device if no resync is going on, or below the resync window.
529 * We take the first readable disk when above the resync window.
532 sectors
= r1_bio
->sectors
;
535 best_dist
= MaxSector
;
536 best_pending_disk
= -1;
537 min_pending
= UINT_MAX
;
538 best_good_sectors
= 0;
540 choose_next_idle
= 0;
542 choose_first
= (conf
->mddev
->recovery_cp
< this_sector
+ sectors
);
544 for (disk
= 0 ; disk
< conf
->raid_disks
* 2 ; disk
++) {
548 unsigned int pending
;
551 rdev
= rcu_dereference(conf
->mirrors
[disk
].rdev
);
552 if (r1_bio
->bios
[disk
] == IO_BLOCKED
554 || test_bit(Unmerged
, &rdev
->flags
)
555 || test_bit(Faulty
, &rdev
->flags
))
557 if (!test_bit(In_sync
, &rdev
->flags
) &&
558 rdev
->recovery_offset
< this_sector
+ sectors
)
560 if (test_bit(WriteMostly
, &rdev
->flags
)) {
561 /* Don't balance among write-mostly, just
562 * use the first as a last resort */
564 if (is_badblock(rdev
, this_sector
, sectors
,
565 &first_bad
, &bad_sectors
)) {
566 if (first_bad
< this_sector
)
567 /* Cannot use this */
569 best_good_sectors
= first_bad
- this_sector
;
571 best_good_sectors
= sectors
;
576 /* This is a reasonable device to use. It might
579 if (is_badblock(rdev
, this_sector
, sectors
,
580 &first_bad
, &bad_sectors
)) {
581 if (best_dist
< MaxSector
)
582 /* already have a better device */
584 if (first_bad
<= this_sector
) {
585 /* cannot read here. If this is the 'primary'
586 * device, then we must not read beyond
587 * bad_sectors from another device..
589 bad_sectors
-= (this_sector
- first_bad
);
590 if (choose_first
&& sectors
> bad_sectors
)
591 sectors
= bad_sectors
;
592 if (best_good_sectors
> sectors
)
593 best_good_sectors
= sectors
;
596 sector_t good_sectors
= first_bad
- this_sector
;
597 if (good_sectors
> best_good_sectors
) {
598 best_good_sectors
= good_sectors
;
606 best_good_sectors
= sectors
;
608 nonrot
= blk_queue_nonrot(bdev_get_queue(rdev
->bdev
));
609 has_nonrot_disk
|= nonrot
;
610 pending
= atomic_read(&rdev
->nr_pending
);
611 dist
= abs(this_sector
- conf
->mirrors
[disk
].head_position
);
616 /* Don't change to another disk for sequential reads */
617 if (conf
->mirrors
[disk
].next_seq_sect
== this_sector
619 int opt_iosize
= bdev_io_opt(rdev
->bdev
) >> 9;
620 struct raid1_info
*mirror
= &conf
->mirrors
[disk
];
624 * If buffered sequential IO size exceeds optimal
625 * iosize, check if there is idle disk. If yes, choose
626 * the idle disk. read_balance could already choose an
627 * idle disk before noticing it's a sequential IO in
628 * this disk. This doesn't matter because this disk
629 * will idle, next time it will be utilized after the
630 * first disk has IO size exceeds optimal iosize. In
631 * this way, iosize of the first disk will be optimal
632 * iosize at least. iosize of the second disk might be
633 * small, but not a big deal since when the second disk
634 * starts IO, the first disk is likely still busy.
636 if (nonrot
&& opt_iosize
> 0 &&
637 mirror
->seq_start
!= MaxSector
&&
638 mirror
->next_seq_sect
> opt_iosize
&&
639 mirror
->next_seq_sect
- opt_iosize
>=
641 choose_next_idle
= 1;
646 /* If device is idle, use it */
652 if (choose_next_idle
)
655 if (min_pending
> pending
) {
656 min_pending
= pending
;
657 best_pending_disk
= disk
;
660 if (dist
< best_dist
) {
662 best_dist_disk
= disk
;
667 * If all disks are rotational, choose the closest disk. If any disk is
668 * non-rotational, choose the disk with less pending request even the
669 * disk is rotational, which might/might not be optimal for raids with
670 * mixed ratation/non-rotational disks depending on workload.
672 if (best_disk
== -1) {
674 best_disk
= best_pending_disk
;
676 best_disk
= best_dist_disk
;
679 if (best_disk
>= 0) {
680 rdev
= rcu_dereference(conf
->mirrors
[best_disk
].rdev
);
683 atomic_inc(&rdev
->nr_pending
);
684 if (test_bit(Faulty
, &rdev
->flags
)) {
685 /* cannot risk returning a device that failed
686 * before we inc'ed nr_pending
688 rdev_dec_pending(rdev
, conf
->mddev
);
691 sectors
= best_good_sectors
;
693 if (conf
->mirrors
[best_disk
].next_seq_sect
!= this_sector
)
694 conf
->mirrors
[best_disk
].seq_start
= this_sector
;
696 conf
->mirrors
[best_disk
].next_seq_sect
= this_sector
+ sectors
;
699 *max_sectors
= sectors
;
704 static int raid1_mergeable_bvec(struct request_queue
*q
,
705 struct bvec_merge_data
*bvm
,
706 struct bio_vec
*biovec
)
708 struct mddev
*mddev
= q
->queuedata
;
709 struct r1conf
*conf
= mddev
->private;
710 sector_t sector
= bvm
->bi_sector
+ get_start_sect(bvm
->bi_bdev
);
711 int max
= biovec
->bv_len
;
713 if (mddev
->merge_check_needed
) {
716 for (disk
= 0; disk
< conf
->raid_disks
* 2; disk
++) {
717 struct md_rdev
*rdev
= rcu_dereference(
718 conf
->mirrors
[disk
].rdev
);
719 if (rdev
&& !test_bit(Faulty
, &rdev
->flags
)) {
720 struct request_queue
*q
=
721 bdev_get_queue(rdev
->bdev
);
722 if (q
->merge_bvec_fn
) {
723 bvm
->bi_sector
= sector
+
725 bvm
->bi_bdev
= rdev
->bdev
;
726 max
= min(max
, q
->merge_bvec_fn(
737 int md_raid1_congested(struct mddev
*mddev
, int bits
)
739 struct r1conf
*conf
= mddev
->private;
742 if ((bits
& (1 << BDI_async_congested
)) &&
743 conf
->pending_count
>= max_queued_requests
)
747 for (i
= 0; i
< conf
->raid_disks
* 2; i
++) {
748 struct md_rdev
*rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
749 if (rdev
&& !test_bit(Faulty
, &rdev
->flags
)) {
750 struct request_queue
*q
= bdev_get_queue(rdev
->bdev
);
754 /* Note the '|| 1' - when read_balance prefers
755 * non-congested targets, it can be removed
757 if ((bits
& (1<<BDI_async_congested
)) || 1)
758 ret
|= bdi_congested(&q
->backing_dev_info
, bits
);
760 ret
&= bdi_congested(&q
->backing_dev_info
, bits
);
766 EXPORT_SYMBOL_GPL(md_raid1_congested
);
768 static int raid1_congested(void *data
, int bits
)
770 struct mddev
*mddev
= data
;
772 return mddev_congested(mddev
, bits
) ||
773 md_raid1_congested(mddev
, bits
);
776 static void flush_pending_writes(struct r1conf
*conf
)
778 /* Any writes that have been queued but are awaiting
779 * bitmap updates get flushed here.
781 spin_lock_irq(&conf
->device_lock
);
783 if (conf
->pending_bio_list
.head
) {
785 bio
= bio_list_get(&conf
->pending_bio_list
);
786 conf
->pending_count
= 0;
787 spin_unlock_irq(&conf
->device_lock
);
788 /* flush any pending bitmap writes to
789 * disk before proceeding w/ I/O */
790 bitmap_unplug(conf
->mddev
->bitmap
);
791 wake_up(&conf
->wait_barrier
);
793 while (bio
) { /* submit pending writes */
794 struct bio
*next
= bio
->bi_next
;
796 if (unlikely((bio
->bi_rw
& REQ_DISCARD
) &&
797 !blk_queue_discard(bdev_get_queue(bio
->bi_bdev
))))
801 generic_make_request(bio
);
805 spin_unlock_irq(&conf
->device_lock
);
809 * Sometimes we need to suspend IO while we do something else,
810 * either some resync/recovery, or reconfigure the array.
811 * To do this we raise a 'barrier'.
812 * The 'barrier' is a counter that can be raised multiple times
813 * to count how many activities are happening which preclude
815 * We can only raise the barrier if there is no pending IO.
816 * i.e. if nr_pending == 0.
817 * We choose only to raise the barrier if no-one is waiting for the
818 * barrier to go down. This means that as soon as an IO request
819 * is ready, no other operations which require a barrier will start
820 * until the IO request has had a chance.
822 * So: regular IO calls 'wait_barrier'. When that returns there
823 * is no backgroup IO happening, It must arrange to call
824 * allow_barrier when it has finished its IO.
825 * backgroup IO calls must call raise_barrier. Once that returns
826 * there is no normal IO happeing. It must arrange to call
827 * lower_barrier when the particular background IO completes.
829 static void raise_barrier(struct r1conf
*conf
, sector_t sector_nr
)
831 spin_lock_irq(&conf
->resync_lock
);
833 /* Wait until no block IO is waiting */
834 wait_event_lock_irq(conf
->wait_barrier
, !conf
->nr_waiting
,
837 /* block any new IO from starting */
839 conf
->next_resync
= sector_nr
;
841 /* For these conditions we must wait:
842 * A: while the array is in frozen state
843 * B: while barrier >= RESYNC_DEPTH, meaning resync reach
844 * the max count which allowed.
845 * C: next_resync + RESYNC_SECTORS > start_next_window, meaning
846 * next resync will reach to the window which normal bios are
848 * D: while there are any active requests in the current window.
850 wait_event_lock_irq(conf
->wait_barrier
,
851 !conf
->array_frozen
&&
852 conf
->barrier
< RESYNC_DEPTH
&&
853 conf
->current_window_requests
== 0 &&
854 (conf
->start_next_window
>=
855 conf
->next_resync
+ RESYNC_SECTORS
),
859 spin_unlock_irq(&conf
->resync_lock
);
862 static void lower_barrier(struct r1conf
*conf
)
865 BUG_ON(conf
->barrier
<= 0);
866 spin_lock_irqsave(&conf
->resync_lock
, flags
);
869 spin_unlock_irqrestore(&conf
->resync_lock
, flags
);
870 wake_up(&conf
->wait_barrier
);
873 static bool need_to_wait_for_sync(struct r1conf
*conf
, struct bio
*bio
)
877 if (conf
->array_frozen
|| !bio
)
879 else if (conf
->barrier
&& bio_data_dir(bio
) == WRITE
) {
880 if ((conf
->mddev
->curr_resync_completed
881 >= bio_end_sector(bio
)) ||
882 (conf
->next_resync
+ NEXT_NORMALIO_DISTANCE
883 <= bio
->bi_iter
.bi_sector
))
892 static sector_t
wait_barrier(struct r1conf
*conf
, struct bio
*bio
)
896 spin_lock_irq(&conf
->resync_lock
);
897 if (need_to_wait_for_sync(conf
, bio
)) {
899 /* Wait for the barrier to drop.
900 * However if there are already pending
901 * requests (preventing the barrier from
902 * rising completely), and the
903 * per-process bio queue isn't empty,
904 * then don't wait, as we need to empty
905 * that queue to allow conf->start_next_window
908 wait_event_lock_irq(conf
->wait_barrier
,
909 !conf
->array_frozen
&&
911 ((conf
->start_next_window
<
912 conf
->next_resync
+ RESYNC_SECTORS
) &&
914 !bio_list_empty(current
->bio_list
))),
919 if (bio
&& bio_data_dir(bio
) == WRITE
) {
920 if (bio
->bi_iter
.bi_sector
>=
921 conf
->mddev
->curr_resync_completed
) {
922 if (conf
->start_next_window
== MaxSector
)
923 conf
->start_next_window
=
925 NEXT_NORMALIO_DISTANCE
;
927 if ((conf
->start_next_window
+ NEXT_NORMALIO_DISTANCE
)
928 <= bio
->bi_iter
.bi_sector
)
929 conf
->next_window_requests
++;
931 conf
->current_window_requests
++;
932 sector
= conf
->start_next_window
;
937 spin_unlock_irq(&conf
->resync_lock
);
941 static void allow_barrier(struct r1conf
*conf
, sector_t start_next_window
,
946 spin_lock_irqsave(&conf
->resync_lock
, flags
);
948 if (start_next_window
) {
949 if (start_next_window
== conf
->start_next_window
) {
950 if (conf
->start_next_window
+ NEXT_NORMALIO_DISTANCE
952 conf
->next_window_requests
--;
954 conf
->current_window_requests
--;
956 conf
->current_window_requests
--;
958 if (!conf
->current_window_requests
) {
959 if (conf
->next_window_requests
) {
960 conf
->current_window_requests
=
961 conf
->next_window_requests
;
962 conf
->next_window_requests
= 0;
963 conf
->start_next_window
+=
964 NEXT_NORMALIO_DISTANCE
;
966 conf
->start_next_window
= MaxSector
;
969 spin_unlock_irqrestore(&conf
->resync_lock
, flags
);
970 wake_up(&conf
->wait_barrier
);
973 static void freeze_array(struct r1conf
*conf
, int extra
)
975 /* stop syncio and normal IO and wait for everything to
977 * We wait until nr_pending match nr_queued+extra
978 * This is called in the context of one normal IO request
979 * that has failed. Thus any sync request that might be pending
980 * will be blocked by nr_pending, and we need to wait for
981 * pending IO requests to complete or be queued for re-try.
982 * Thus the number queued (nr_queued) plus this request (extra)
983 * must match the number of pending IOs (nr_pending) before
986 spin_lock_irq(&conf
->resync_lock
);
987 conf
->array_frozen
= 1;
988 wait_event_lock_irq_cmd(conf
->wait_barrier
,
989 conf
->nr_pending
== conf
->nr_queued
+extra
,
991 flush_pending_writes(conf
));
992 spin_unlock_irq(&conf
->resync_lock
);
994 static void unfreeze_array(struct r1conf
*conf
)
996 /* reverse the effect of the freeze */
997 spin_lock_irq(&conf
->resync_lock
);
998 conf
->array_frozen
= 0;
999 wake_up(&conf
->wait_barrier
);
1000 spin_unlock_irq(&conf
->resync_lock
);
1003 /* duplicate the data pages for behind I/O
1005 static void alloc_behind_pages(struct bio
*bio
, struct r1bio
*r1_bio
)
1008 struct bio_vec
*bvec
;
1009 struct bio_vec
*bvecs
= kzalloc(bio
->bi_vcnt
* sizeof(struct bio_vec
),
1011 if (unlikely(!bvecs
))
1014 bio_for_each_segment_all(bvec
, bio
, i
) {
1016 bvecs
[i
].bv_page
= alloc_page(GFP_NOIO
);
1017 if (unlikely(!bvecs
[i
].bv_page
))
1019 memcpy(kmap(bvecs
[i
].bv_page
) + bvec
->bv_offset
,
1020 kmap(bvec
->bv_page
) + bvec
->bv_offset
, bvec
->bv_len
);
1021 kunmap(bvecs
[i
].bv_page
);
1022 kunmap(bvec
->bv_page
);
1024 r1_bio
->behind_bvecs
= bvecs
;
1025 r1_bio
->behind_page_count
= bio
->bi_vcnt
;
1026 set_bit(R1BIO_BehindIO
, &r1_bio
->state
);
1030 for (i
= 0; i
< bio
->bi_vcnt
; i
++)
1031 if (bvecs
[i
].bv_page
)
1032 put_page(bvecs
[i
].bv_page
);
1034 pr_debug("%dB behind alloc failed, doing sync I/O\n",
1035 bio
->bi_iter
.bi_size
);
1038 struct raid1_plug_cb
{
1039 struct blk_plug_cb cb
;
1040 struct bio_list pending
;
1044 static void raid1_unplug(struct blk_plug_cb
*cb
, bool from_schedule
)
1046 struct raid1_plug_cb
*plug
= container_of(cb
, struct raid1_plug_cb
,
1048 struct mddev
*mddev
= plug
->cb
.data
;
1049 struct r1conf
*conf
= mddev
->private;
1052 if (from_schedule
|| current
->bio_list
) {
1053 spin_lock_irq(&conf
->device_lock
);
1054 bio_list_merge(&conf
->pending_bio_list
, &plug
->pending
);
1055 conf
->pending_count
+= plug
->pending_cnt
;
1056 spin_unlock_irq(&conf
->device_lock
);
1057 wake_up(&conf
->wait_barrier
);
1058 md_wakeup_thread(mddev
->thread
);
1063 /* we aren't scheduling, so we can do the write-out directly. */
1064 bio
= bio_list_get(&plug
->pending
);
1065 bitmap_unplug(mddev
->bitmap
);
1066 wake_up(&conf
->wait_barrier
);
1068 while (bio
) { /* submit pending writes */
1069 struct bio
*next
= bio
->bi_next
;
1070 bio
->bi_next
= NULL
;
1071 if (unlikely((bio
->bi_rw
& REQ_DISCARD
) &&
1072 !blk_queue_discard(bdev_get_queue(bio
->bi_bdev
))))
1073 /* Just ignore it */
1076 generic_make_request(bio
);
1082 static void make_request(struct mddev
*mddev
, struct bio
* bio
)
1084 struct r1conf
*conf
= mddev
->private;
1085 struct raid1_info
*mirror
;
1086 struct r1bio
*r1_bio
;
1087 struct bio
*read_bio
;
1089 struct bitmap
*bitmap
;
1090 unsigned long flags
;
1091 const int rw
= bio_data_dir(bio
);
1092 const unsigned long do_sync
= (bio
->bi_rw
& REQ_SYNC
);
1093 const unsigned long do_flush_fua
= (bio
->bi_rw
& (REQ_FLUSH
| REQ_FUA
));
1094 const unsigned long do_discard
= (bio
->bi_rw
1095 & (REQ_DISCARD
| REQ_SECURE
));
1096 const unsigned long do_same
= (bio
->bi_rw
& REQ_WRITE_SAME
);
1097 struct md_rdev
*blocked_rdev
;
1098 struct blk_plug_cb
*cb
;
1099 struct raid1_plug_cb
*plug
= NULL
;
1101 int sectors_handled
;
1103 sector_t start_next_window
;
1106 * Register the new request and wait if the reconstruction
1107 * thread has put up a bar for new requests.
1108 * Continue immediately if no resync is active currently.
1111 md_write_start(mddev
, bio
); /* wait on superblock update early */
1113 if (bio_data_dir(bio
) == WRITE
&&
1114 bio_end_sector(bio
) > mddev
->suspend_lo
&&
1115 bio
->bi_iter
.bi_sector
< mddev
->suspend_hi
) {
1116 /* As the suspend_* range is controlled by
1117 * userspace, we want an interruptible
1122 flush_signals(current
);
1123 prepare_to_wait(&conf
->wait_barrier
,
1124 &w
, TASK_INTERRUPTIBLE
);
1125 if (bio_end_sector(bio
) <= mddev
->suspend_lo
||
1126 bio
->bi_iter
.bi_sector
>= mddev
->suspend_hi
)
1130 finish_wait(&conf
->wait_barrier
, &w
);
1133 start_next_window
= wait_barrier(conf
, bio
);
1135 bitmap
= mddev
->bitmap
;
1138 * make_request() can abort the operation when READA is being
1139 * used and no empty request is available.
1142 r1_bio
= mempool_alloc(conf
->r1bio_pool
, GFP_NOIO
);
1144 r1_bio
->master_bio
= bio
;
1145 r1_bio
->sectors
= bio_sectors(bio
);
1147 r1_bio
->mddev
= mddev
;
1148 r1_bio
->sector
= bio
->bi_iter
.bi_sector
;
1150 /* We might need to issue multiple reads to different
1151 * devices if there are bad blocks around, so we keep
1152 * track of the number of reads in bio->bi_phys_segments.
1153 * If this is 0, there is only one r1_bio and no locking
1154 * will be needed when requests complete. If it is
1155 * non-zero, then it is the number of not-completed requests.
1157 bio
->bi_phys_segments
= 0;
1158 clear_bit(BIO_SEG_VALID
, &bio
->bi_flags
);
1162 * read balancing logic:
1167 rdisk
= read_balance(conf
, r1_bio
, &max_sectors
);
1170 /* couldn't find anywhere to read from */
1171 raid_end_bio_io(r1_bio
);
1174 mirror
= conf
->mirrors
+ rdisk
;
1176 if (test_bit(WriteMostly
, &mirror
->rdev
->flags
) &&
1178 /* Reading from a write-mostly device must
1179 * take care not to over-take any writes
1182 wait_event(bitmap
->behind_wait
,
1183 atomic_read(&bitmap
->behind_writes
) == 0);
1185 r1_bio
->read_disk
= rdisk
;
1186 r1_bio
->start_next_window
= 0;
1188 read_bio
= bio_clone_mddev(bio
, GFP_NOIO
, mddev
);
1189 bio_trim(read_bio
, r1_bio
->sector
- bio
->bi_iter
.bi_sector
,
1192 r1_bio
->bios
[rdisk
] = read_bio
;
1194 read_bio
->bi_iter
.bi_sector
= r1_bio
->sector
+
1195 mirror
->rdev
->data_offset
;
1196 read_bio
->bi_bdev
= mirror
->rdev
->bdev
;
1197 read_bio
->bi_end_io
= raid1_end_read_request
;
1198 read_bio
->bi_rw
= READ
| do_sync
;
1199 read_bio
->bi_private
= r1_bio
;
1201 if (max_sectors
< r1_bio
->sectors
) {
1202 /* could not read all from this device, so we will
1203 * need another r1_bio.
1206 sectors_handled
= (r1_bio
->sector
+ max_sectors
1207 - bio
->bi_iter
.bi_sector
);
1208 r1_bio
->sectors
= max_sectors
;
1209 spin_lock_irq(&conf
->device_lock
);
1210 if (bio
->bi_phys_segments
== 0)
1211 bio
->bi_phys_segments
= 2;
1213 bio
->bi_phys_segments
++;
1214 spin_unlock_irq(&conf
->device_lock
);
1215 /* Cannot call generic_make_request directly
1216 * as that will be queued in __make_request
1217 * and subsequent mempool_alloc might block waiting
1218 * for it. So hand bio over to raid1d.
1220 reschedule_retry(r1_bio
);
1222 r1_bio
= mempool_alloc(conf
->r1bio_pool
, GFP_NOIO
);
1224 r1_bio
->master_bio
= bio
;
1225 r1_bio
->sectors
= bio_sectors(bio
) - sectors_handled
;
1227 r1_bio
->mddev
= mddev
;
1228 r1_bio
->sector
= bio
->bi_iter
.bi_sector
+
1232 generic_make_request(read_bio
);
1239 if (conf
->pending_count
>= max_queued_requests
) {
1240 md_wakeup_thread(mddev
->thread
);
1241 wait_event(conf
->wait_barrier
,
1242 conf
->pending_count
< max_queued_requests
);
1244 /* first select target devices under rcu_lock and
1245 * inc refcount on their rdev. Record them by setting
1247 * If there are known/acknowledged bad blocks on any device on
1248 * which we have seen a write error, we want to avoid writing those
1250 * This potentially requires several writes to write around
1251 * the bad blocks. Each set of writes gets it's own r1bio
1252 * with a set of bios attached.
1255 disks
= conf
->raid_disks
* 2;
1257 r1_bio
->start_next_window
= start_next_window
;
1258 blocked_rdev
= NULL
;
1260 max_sectors
= r1_bio
->sectors
;
1261 for (i
= 0; i
< disks
; i
++) {
1262 struct md_rdev
*rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
1263 if (rdev
&& unlikely(test_bit(Blocked
, &rdev
->flags
))) {
1264 atomic_inc(&rdev
->nr_pending
);
1265 blocked_rdev
= rdev
;
1268 r1_bio
->bios
[i
] = NULL
;
1269 if (!rdev
|| test_bit(Faulty
, &rdev
->flags
)
1270 || test_bit(Unmerged
, &rdev
->flags
)) {
1271 if (i
< conf
->raid_disks
)
1272 set_bit(R1BIO_Degraded
, &r1_bio
->state
);
1276 atomic_inc(&rdev
->nr_pending
);
1277 if (test_bit(WriteErrorSeen
, &rdev
->flags
)) {
1282 is_bad
= is_badblock(rdev
, r1_bio
->sector
,
1284 &first_bad
, &bad_sectors
);
1286 /* mustn't write here until the bad block is
1288 set_bit(BlockedBadBlocks
, &rdev
->flags
);
1289 blocked_rdev
= rdev
;
1292 if (is_bad
&& first_bad
<= r1_bio
->sector
) {
1293 /* Cannot write here at all */
1294 bad_sectors
-= (r1_bio
->sector
- first_bad
);
1295 if (bad_sectors
< max_sectors
)
1296 /* mustn't write more than bad_sectors
1297 * to other devices yet
1299 max_sectors
= bad_sectors
;
1300 rdev_dec_pending(rdev
, mddev
);
1301 /* We don't set R1BIO_Degraded as that
1302 * only applies if the disk is
1303 * missing, so it might be re-added,
1304 * and we want to know to recover this
1306 * In this case the device is here,
1307 * and the fact that this chunk is not
1308 * in-sync is recorded in the bad
1314 int good_sectors
= first_bad
- r1_bio
->sector
;
1315 if (good_sectors
< max_sectors
)
1316 max_sectors
= good_sectors
;
1319 r1_bio
->bios
[i
] = bio
;
1323 if (unlikely(blocked_rdev
)) {
1324 /* Wait for this device to become unblocked */
1326 sector_t old
= start_next_window
;
1328 for (j
= 0; j
< i
; j
++)
1329 if (r1_bio
->bios
[j
])
1330 rdev_dec_pending(conf
->mirrors
[j
].rdev
, mddev
);
1332 allow_barrier(conf
, start_next_window
, bio
->bi_iter
.bi_sector
);
1333 md_wait_for_blocked_rdev(blocked_rdev
, mddev
);
1334 start_next_window
= wait_barrier(conf
, bio
);
1336 * We must make sure the multi r1bios of bio have
1337 * the same value of bi_phys_segments
1339 if (bio
->bi_phys_segments
&& old
&&
1340 old
!= start_next_window
)
1341 /* Wait for the former r1bio(s) to complete */
1342 wait_event(conf
->wait_barrier
,
1343 bio
->bi_phys_segments
== 1);
1347 if (max_sectors
< r1_bio
->sectors
) {
1348 /* We are splitting this write into multiple parts, so
1349 * we need to prepare for allocating another r1_bio.
1351 r1_bio
->sectors
= max_sectors
;
1352 spin_lock_irq(&conf
->device_lock
);
1353 if (bio
->bi_phys_segments
== 0)
1354 bio
->bi_phys_segments
= 2;
1356 bio
->bi_phys_segments
++;
1357 spin_unlock_irq(&conf
->device_lock
);
1359 sectors_handled
= r1_bio
->sector
+ max_sectors
- bio
->bi_iter
.bi_sector
;
1361 atomic_set(&r1_bio
->remaining
, 1);
1362 atomic_set(&r1_bio
->behind_remaining
, 0);
1365 for (i
= 0; i
< disks
; i
++) {
1367 if (!r1_bio
->bios
[i
])
1370 mbio
= bio_clone_mddev(bio
, GFP_NOIO
, mddev
);
1371 bio_trim(mbio
, r1_bio
->sector
- bio
->bi_iter
.bi_sector
, max_sectors
);
1375 * Not if there are too many, or cannot
1376 * allocate memory, or a reader on WriteMostly
1377 * is waiting for behind writes to flush */
1379 (atomic_read(&bitmap
->behind_writes
)
1380 < mddev
->bitmap_info
.max_write_behind
) &&
1381 !waitqueue_active(&bitmap
->behind_wait
))
1382 alloc_behind_pages(mbio
, r1_bio
);
1384 bitmap_startwrite(bitmap
, r1_bio
->sector
,
1386 test_bit(R1BIO_BehindIO
,
1390 if (r1_bio
->behind_bvecs
) {
1391 struct bio_vec
*bvec
;
1395 * We trimmed the bio, so _all is legit
1397 bio_for_each_segment_all(bvec
, mbio
, j
)
1398 bvec
->bv_page
= r1_bio
->behind_bvecs
[j
].bv_page
;
1399 if (test_bit(WriteMostly
, &conf
->mirrors
[i
].rdev
->flags
))
1400 atomic_inc(&r1_bio
->behind_remaining
);
1403 r1_bio
->bios
[i
] = mbio
;
1405 mbio
->bi_iter
.bi_sector
= (r1_bio
->sector
+
1406 conf
->mirrors
[i
].rdev
->data_offset
);
1407 mbio
->bi_bdev
= conf
->mirrors
[i
].rdev
->bdev
;
1408 mbio
->bi_end_io
= raid1_end_write_request
;
1410 WRITE
| do_flush_fua
| do_sync
| do_discard
| do_same
;
1411 mbio
->bi_private
= r1_bio
;
1413 atomic_inc(&r1_bio
->remaining
);
1415 cb
= blk_check_plugged(raid1_unplug
, mddev
, sizeof(*plug
));
1417 plug
= container_of(cb
, struct raid1_plug_cb
, cb
);
1420 spin_lock_irqsave(&conf
->device_lock
, flags
);
1422 bio_list_add(&plug
->pending
, mbio
);
1423 plug
->pending_cnt
++;
1425 bio_list_add(&conf
->pending_bio_list
, mbio
);
1426 conf
->pending_count
++;
1428 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
1430 md_wakeup_thread(mddev
->thread
);
1432 /* Mustn't call r1_bio_write_done before this next test,
1433 * as it could result in the bio being freed.
1435 if (sectors_handled
< bio_sectors(bio
)) {
1436 r1_bio_write_done(r1_bio
);
1437 /* We need another r1_bio. It has already been counted
1438 * in bio->bi_phys_segments
1440 r1_bio
= mempool_alloc(conf
->r1bio_pool
, GFP_NOIO
);
1441 r1_bio
->master_bio
= bio
;
1442 r1_bio
->sectors
= bio_sectors(bio
) - sectors_handled
;
1444 r1_bio
->mddev
= mddev
;
1445 r1_bio
->sector
= bio
->bi_iter
.bi_sector
+ sectors_handled
;
1449 r1_bio_write_done(r1_bio
);
1451 /* In case raid1d snuck in to freeze_array */
1452 wake_up(&conf
->wait_barrier
);
1455 static void status(struct seq_file
*seq
, struct mddev
*mddev
)
1457 struct r1conf
*conf
= mddev
->private;
1460 seq_printf(seq
, " [%d/%d] [", conf
->raid_disks
,
1461 conf
->raid_disks
- mddev
->degraded
);
1463 for (i
= 0; i
< conf
->raid_disks
; i
++) {
1464 struct md_rdev
*rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
1465 seq_printf(seq
, "%s",
1466 rdev
&& test_bit(In_sync
, &rdev
->flags
) ? "U" : "_");
1469 seq_printf(seq
, "]");
1472 static void error(struct mddev
*mddev
, struct md_rdev
*rdev
)
1474 char b
[BDEVNAME_SIZE
];
1475 struct r1conf
*conf
= mddev
->private;
1478 * If it is not operational, then we have already marked it as dead
1479 * else if it is the last working disks, ignore the error, let the
1480 * next level up know.
1481 * else mark the drive as failed
1483 if (test_bit(In_sync
, &rdev
->flags
)
1484 && (conf
->raid_disks
- mddev
->degraded
) == 1) {
1486 * Don't fail the drive, act as though we were just a
1487 * normal single drive.
1488 * However don't try a recovery from this drive as
1489 * it is very likely to fail.
1491 conf
->recovery_disabled
= mddev
->recovery_disabled
;
1494 set_bit(Blocked
, &rdev
->flags
);
1495 if (test_and_clear_bit(In_sync
, &rdev
->flags
)) {
1496 unsigned long flags
;
1497 spin_lock_irqsave(&conf
->device_lock
, flags
);
1499 set_bit(Faulty
, &rdev
->flags
);
1500 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
1502 set_bit(Faulty
, &rdev
->flags
);
1504 * if recovery is running, make sure it aborts.
1506 set_bit(MD_RECOVERY_INTR
, &mddev
->recovery
);
1507 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
1509 "md/raid1:%s: Disk failure on %s, disabling device.\n"
1510 "md/raid1:%s: Operation continuing on %d devices.\n",
1511 mdname(mddev
), bdevname(rdev
->bdev
, b
),
1512 mdname(mddev
), conf
->raid_disks
- mddev
->degraded
);
1515 static void print_conf(struct r1conf
*conf
)
1519 printk(KERN_DEBUG
"RAID1 conf printout:\n");
1521 printk(KERN_DEBUG
"(!conf)\n");
1524 printk(KERN_DEBUG
" --- wd:%d rd:%d\n", conf
->raid_disks
- conf
->mddev
->degraded
,
1528 for (i
= 0; i
< conf
->raid_disks
; i
++) {
1529 char b
[BDEVNAME_SIZE
];
1530 struct md_rdev
*rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
1532 printk(KERN_DEBUG
" disk %d, wo:%d, o:%d, dev:%s\n",
1533 i
, !test_bit(In_sync
, &rdev
->flags
),
1534 !test_bit(Faulty
, &rdev
->flags
),
1535 bdevname(rdev
->bdev
,b
));
1540 static void close_sync(struct r1conf
*conf
)
1542 wait_barrier(conf
, NULL
);
1543 allow_barrier(conf
, 0, 0);
1545 mempool_destroy(conf
->r1buf_pool
);
1546 conf
->r1buf_pool
= NULL
;
1548 spin_lock_irq(&conf
->resync_lock
);
1549 conf
->next_resync
= 0;
1550 conf
->start_next_window
= MaxSector
;
1551 conf
->current_window_requests
+=
1552 conf
->next_window_requests
;
1553 conf
->next_window_requests
= 0;
1554 spin_unlock_irq(&conf
->resync_lock
);
1557 static int raid1_spare_active(struct mddev
*mddev
)
1560 struct r1conf
*conf
= mddev
->private;
1562 unsigned long flags
;
1565 * Find all failed disks within the RAID1 configuration
1566 * and mark them readable.
1567 * Called under mddev lock, so rcu protection not needed.
1569 for (i
= 0; i
< conf
->raid_disks
; i
++) {
1570 struct md_rdev
*rdev
= conf
->mirrors
[i
].rdev
;
1571 struct md_rdev
*repl
= conf
->mirrors
[conf
->raid_disks
+ i
].rdev
;
1573 && repl
->recovery_offset
== MaxSector
1574 && !test_bit(Faulty
, &repl
->flags
)
1575 && !test_and_set_bit(In_sync
, &repl
->flags
)) {
1576 /* replacement has just become active */
1578 !test_and_clear_bit(In_sync
, &rdev
->flags
))
1581 /* Replaced device not technically
1582 * faulty, but we need to be sure
1583 * it gets removed and never re-added
1585 set_bit(Faulty
, &rdev
->flags
);
1586 sysfs_notify_dirent_safe(
1591 && rdev
->recovery_offset
== MaxSector
1592 && !test_bit(Faulty
, &rdev
->flags
)
1593 && !test_and_set_bit(In_sync
, &rdev
->flags
)) {
1595 sysfs_notify_dirent_safe(rdev
->sysfs_state
);
1598 spin_lock_irqsave(&conf
->device_lock
, flags
);
1599 mddev
->degraded
-= count
;
1600 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
1606 static int raid1_add_disk(struct mddev
*mddev
, struct md_rdev
*rdev
)
1608 struct r1conf
*conf
= mddev
->private;
1611 struct raid1_info
*p
;
1613 int last
= conf
->raid_disks
- 1;
1614 struct request_queue
*q
= bdev_get_queue(rdev
->bdev
);
1616 if (mddev
->recovery_disabled
== conf
->recovery_disabled
)
1619 if (rdev
->raid_disk
>= 0)
1620 first
= last
= rdev
->raid_disk
;
1622 if (q
->merge_bvec_fn
) {
1623 set_bit(Unmerged
, &rdev
->flags
);
1624 mddev
->merge_check_needed
= 1;
1627 for (mirror
= first
; mirror
<= last
; mirror
++) {
1628 p
= conf
->mirrors
+mirror
;
1632 disk_stack_limits(mddev
->gendisk
, rdev
->bdev
,
1633 rdev
->data_offset
<< 9);
1635 p
->head_position
= 0;
1636 rdev
->raid_disk
= mirror
;
1638 /* As all devices are equivalent, we don't need a full recovery
1639 * if this was recently any drive of the array
1641 if (rdev
->saved_raid_disk
< 0)
1643 rcu_assign_pointer(p
->rdev
, rdev
);
1646 if (test_bit(WantReplacement
, &p
->rdev
->flags
) &&
1647 p
[conf
->raid_disks
].rdev
== NULL
) {
1648 /* Add this device as a replacement */
1649 clear_bit(In_sync
, &rdev
->flags
);
1650 set_bit(Replacement
, &rdev
->flags
);
1651 rdev
->raid_disk
= mirror
;
1654 rcu_assign_pointer(p
[conf
->raid_disks
].rdev
, rdev
);
1658 if (err
== 0 && test_bit(Unmerged
, &rdev
->flags
)) {
1659 /* Some requests might not have seen this new
1660 * merge_bvec_fn. We must wait for them to complete
1661 * before merging the device fully.
1662 * First we make sure any code which has tested
1663 * our function has submitted the request, then
1664 * we wait for all outstanding requests to complete.
1666 synchronize_sched();
1667 freeze_array(conf
, 0);
1668 unfreeze_array(conf
);
1669 clear_bit(Unmerged
, &rdev
->flags
);
1671 md_integrity_add_rdev(rdev
, mddev
);
1672 if (mddev
->queue
&& blk_queue_discard(bdev_get_queue(rdev
->bdev
)))
1673 queue_flag_set_unlocked(QUEUE_FLAG_DISCARD
, mddev
->queue
);
1678 static int raid1_remove_disk(struct mddev
*mddev
, struct md_rdev
*rdev
)
1680 struct r1conf
*conf
= mddev
->private;
1682 int number
= rdev
->raid_disk
;
1683 struct raid1_info
*p
= conf
->mirrors
+ number
;
1685 if (rdev
!= p
->rdev
)
1686 p
= conf
->mirrors
+ conf
->raid_disks
+ number
;
1689 if (rdev
== p
->rdev
) {
1690 if (test_bit(In_sync
, &rdev
->flags
) ||
1691 atomic_read(&rdev
->nr_pending
)) {
1695 /* Only remove non-faulty devices if recovery
1698 if (!test_bit(Faulty
, &rdev
->flags
) &&
1699 mddev
->recovery_disabled
!= conf
->recovery_disabled
&&
1700 mddev
->degraded
< conf
->raid_disks
) {
1706 if (atomic_read(&rdev
->nr_pending
)) {
1707 /* lost the race, try later */
1711 } else if (conf
->mirrors
[conf
->raid_disks
+ number
].rdev
) {
1712 /* We just removed a device that is being replaced.
1713 * Move down the replacement. We drain all IO before
1714 * doing this to avoid confusion.
1716 struct md_rdev
*repl
=
1717 conf
->mirrors
[conf
->raid_disks
+ number
].rdev
;
1718 freeze_array(conf
, 0);
1719 clear_bit(Replacement
, &repl
->flags
);
1721 conf
->mirrors
[conf
->raid_disks
+ number
].rdev
= NULL
;
1722 unfreeze_array(conf
);
1723 clear_bit(WantReplacement
, &rdev
->flags
);
1725 clear_bit(WantReplacement
, &rdev
->flags
);
1726 err
= md_integrity_register(mddev
);
1734 static void end_sync_read(struct bio
*bio
, int error
)
1736 struct r1bio
*r1_bio
= bio
->bi_private
;
1738 update_head_pos(r1_bio
->read_disk
, r1_bio
);
1741 * we have read a block, now it needs to be re-written,
1742 * or re-read if the read failed.
1743 * We don't do much here, just schedule handling by raid1d
1745 if (test_bit(BIO_UPTODATE
, &bio
->bi_flags
))
1746 set_bit(R1BIO_Uptodate
, &r1_bio
->state
);
1748 if (atomic_dec_and_test(&r1_bio
->remaining
))
1749 reschedule_retry(r1_bio
);
1752 static void end_sync_write(struct bio
*bio
, int error
)
1754 int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
1755 struct r1bio
*r1_bio
= bio
->bi_private
;
1756 struct mddev
*mddev
= r1_bio
->mddev
;
1757 struct r1conf
*conf
= mddev
->private;
1762 mirror
= find_bio_disk(r1_bio
, bio
);
1765 sector_t sync_blocks
= 0;
1766 sector_t s
= r1_bio
->sector
;
1767 long sectors_to_go
= r1_bio
->sectors
;
1768 /* make sure these bits doesn't get cleared. */
1770 bitmap_end_sync(mddev
->bitmap
, s
,
1773 sectors_to_go
-= sync_blocks
;
1774 } while (sectors_to_go
> 0);
1775 set_bit(WriteErrorSeen
,
1776 &conf
->mirrors
[mirror
].rdev
->flags
);
1777 if (!test_and_set_bit(WantReplacement
,
1778 &conf
->mirrors
[mirror
].rdev
->flags
))
1779 set_bit(MD_RECOVERY_NEEDED
, &
1781 set_bit(R1BIO_WriteError
, &r1_bio
->state
);
1782 } else if (is_badblock(conf
->mirrors
[mirror
].rdev
,
1785 &first_bad
, &bad_sectors
) &&
1786 !is_badblock(conf
->mirrors
[r1_bio
->read_disk
].rdev
,
1789 &first_bad
, &bad_sectors
)
1791 set_bit(R1BIO_MadeGood
, &r1_bio
->state
);
1793 if (atomic_dec_and_test(&r1_bio
->remaining
)) {
1794 int s
= r1_bio
->sectors
;
1795 if (test_bit(R1BIO_MadeGood
, &r1_bio
->state
) ||
1796 test_bit(R1BIO_WriteError
, &r1_bio
->state
))
1797 reschedule_retry(r1_bio
);
1800 md_done_sync(mddev
, s
, uptodate
);
1805 static int r1_sync_page_io(struct md_rdev
*rdev
, sector_t sector
,
1806 int sectors
, struct page
*page
, int rw
)
1808 if (sync_page_io(rdev
, sector
, sectors
<< 9, page
, rw
, false))
1812 set_bit(WriteErrorSeen
, &rdev
->flags
);
1813 if (!test_and_set_bit(WantReplacement
,
1815 set_bit(MD_RECOVERY_NEEDED
, &
1816 rdev
->mddev
->recovery
);
1818 /* need to record an error - either for the block or the device */
1819 if (!rdev_set_badblocks(rdev
, sector
, sectors
, 0))
1820 md_error(rdev
->mddev
, rdev
);
1824 static int fix_sync_read_error(struct r1bio
*r1_bio
)
1826 /* Try some synchronous reads of other devices to get
1827 * good data, much like with normal read errors. Only
1828 * read into the pages we already have so we don't
1829 * need to re-issue the read request.
1830 * We don't need to freeze the array, because being in an
1831 * active sync request, there is no normal IO, and
1832 * no overlapping syncs.
1833 * We don't need to check is_badblock() again as we
1834 * made sure that anything with a bad block in range
1835 * will have bi_end_io clear.
1837 struct mddev
*mddev
= r1_bio
->mddev
;
1838 struct r1conf
*conf
= mddev
->private;
1839 struct bio
*bio
= r1_bio
->bios
[r1_bio
->read_disk
];
1840 sector_t sect
= r1_bio
->sector
;
1841 int sectors
= r1_bio
->sectors
;
1846 int d
= r1_bio
->read_disk
;
1848 struct md_rdev
*rdev
;
1851 if (s
> (PAGE_SIZE
>>9))
1854 if (r1_bio
->bios
[d
]->bi_end_io
== end_sync_read
) {
1855 /* No rcu protection needed here devices
1856 * can only be removed when no resync is
1857 * active, and resync is currently active
1859 rdev
= conf
->mirrors
[d
].rdev
;
1860 if (sync_page_io(rdev
, sect
, s
<<9,
1861 bio
->bi_io_vec
[idx
].bv_page
,
1868 if (d
== conf
->raid_disks
* 2)
1870 } while (!success
&& d
!= r1_bio
->read_disk
);
1873 char b
[BDEVNAME_SIZE
];
1875 /* Cannot read from anywhere, this block is lost.
1876 * Record a bad block on each device. If that doesn't
1877 * work just disable and interrupt the recovery.
1878 * Don't fail devices as that won't really help.
1880 printk(KERN_ALERT
"md/raid1:%s: %s: unrecoverable I/O read error"
1881 " for block %llu\n",
1883 bdevname(bio
->bi_bdev
, b
),
1884 (unsigned long long)r1_bio
->sector
);
1885 for (d
= 0; d
< conf
->raid_disks
* 2; d
++) {
1886 rdev
= conf
->mirrors
[d
].rdev
;
1887 if (!rdev
|| test_bit(Faulty
, &rdev
->flags
))
1889 if (!rdev_set_badblocks(rdev
, sect
, s
, 0))
1893 conf
->recovery_disabled
=
1894 mddev
->recovery_disabled
;
1895 set_bit(MD_RECOVERY_INTR
, &mddev
->recovery
);
1896 md_done_sync(mddev
, r1_bio
->sectors
, 0);
1908 /* write it back and re-read */
1909 while (d
!= r1_bio
->read_disk
) {
1911 d
= conf
->raid_disks
* 2;
1913 if (r1_bio
->bios
[d
]->bi_end_io
!= end_sync_read
)
1915 rdev
= conf
->mirrors
[d
].rdev
;
1916 if (r1_sync_page_io(rdev
, sect
, s
,
1917 bio
->bi_io_vec
[idx
].bv_page
,
1919 r1_bio
->bios
[d
]->bi_end_io
= NULL
;
1920 rdev_dec_pending(rdev
, mddev
);
1924 while (d
!= r1_bio
->read_disk
) {
1926 d
= conf
->raid_disks
* 2;
1928 if (r1_bio
->bios
[d
]->bi_end_io
!= end_sync_read
)
1930 rdev
= conf
->mirrors
[d
].rdev
;
1931 if (r1_sync_page_io(rdev
, sect
, s
,
1932 bio
->bi_io_vec
[idx
].bv_page
,
1934 atomic_add(s
, &rdev
->corrected_errors
);
1940 set_bit(R1BIO_Uptodate
, &r1_bio
->state
);
1941 set_bit(BIO_UPTODATE
, &bio
->bi_flags
);
1945 static void process_checks(struct r1bio
*r1_bio
)
1947 /* We have read all readable devices. If we haven't
1948 * got the block, then there is no hope left.
1949 * If we have, then we want to do a comparison
1950 * and skip the write if everything is the same.
1951 * If any blocks failed to read, then we need to
1952 * attempt an over-write
1954 struct mddev
*mddev
= r1_bio
->mddev
;
1955 struct r1conf
*conf
= mddev
->private;
1960 /* Fix variable parts of all bios */
1961 vcnt
= (r1_bio
->sectors
+ PAGE_SIZE
/ 512 - 1) >> (PAGE_SHIFT
- 9);
1962 for (i
= 0; i
< conf
->raid_disks
* 2; i
++) {
1966 struct bio
*b
= r1_bio
->bios
[i
];
1967 if (b
->bi_end_io
!= end_sync_read
)
1969 /* fixup the bio for reuse, but preserve BIO_UPTODATE */
1970 uptodate
= test_bit(BIO_UPTODATE
, &b
->bi_flags
);
1973 clear_bit(BIO_UPTODATE
, &b
->bi_flags
);
1975 b
->bi_iter
.bi_size
= r1_bio
->sectors
<< 9;
1976 b
->bi_iter
.bi_sector
= r1_bio
->sector
+
1977 conf
->mirrors
[i
].rdev
->data_offset
;
1978 b
->bi_bdev
= conf
->mirrors
[i
].rdev
->bdev
;
1979 b
->bi_end_io
= end_sync_read
;
1980 b
->bi_private
= r1_bio
;
1982 size
= b
->bi_iter
.bi_size
;
1983 for (j
= 0; j
< vcnt
; j
++) {
1985 bi
= &b
->bi_io_vec
[j
];
1987 if (size
> PAGE_SIZE
)
1988 bi
->bv_len
= PAGE_SIZE
;
1994 for (primary
= 0; primary
< conf
->raid_disks
* 2; primary
++)
1995 if (r1_bio
->bios
[primary
]->bi_end_io
== end_sync_read
&&
1996 test_bit(BIO_UPTODATE
, &r1_bio
->bios
[primary
]->bi_flags
)) {
1997 r1_bio
->bios
[primary
]->bi_end_io
= NULL
;
1998 rdev_dec_pending(conf
->mirrors
[primary
].rdev
, mddev
);
2001 r1_bio
->read_disk
= primary
;
2002 for (i
= 0; i
< conf
->raid_disks
* 2; i
++) {
2004 struct bio
*pbio
= r1_bio
->bios
[primary
];
2005 struct bio
*sbio
= r1_bio
->bios
[i
];
2006 int uptodate
= test_bit(BIO_UPTODATE
, &sbio
->bi_flags
);
2008 if (sbio
->bi_end_io
!= end_sync_read
)
2010 /* Now we can 'fixup' the BIO_UPTODATE flag */
2011 set_bit(BIO_UPTODATE
, &sbio
->bi_flags
);
2014 for (j
= vcnt
; j
-- ; ) {
2016 p
= pbio
->bi_io_vec
[j
].bv_page
;
2017 s
= sbio
->bi_io_vec
[j
].bv_page
;
2018 if (memcmp(page_address(p
),
2020 sbio
->bi_io_vec
[j
].bv_len
))
2026 atomic64_add(r1_bio
->sectors
, &mddev
->resync_mismatches
);
2027 if (j
< 0 || (test_bit(MD_RECOVERY_CHECK
, &mddev
->recovery
)
2029 /* No need to write to this device. */
2030 sbio
->bi_end_io
= NULL
;
2031 rdev_dec_pending(conf
->mirrors
[i
].rdev
, mddev
);
2035 bio_copy_data(sbio
, pbio
);
2039 static void sync_request_write(struct mddev
*mddev
, struct r1bio
*r1_bio
)
2041 struct r1conf
*conf
= mddev
->private;
2043 int disks
= conf
->raid_disks
* 2;
2044 struct bio
*bio
, *wbio
;
2046 bio
= r1_bio
->bios
[r1_bio
->read_disk
];
2048 if (!test_bit(R1BIO_Uptodate
, &r1_bio
->state
))
2049 /* ouch - failed to read all of that. */
2050 if (!fix_sync_read_error(r1_bio
))
2053 if (test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
))
2054 process_checks(r1_bio
);
2059 atomic_set(&r1_bio
->remaining
, 1);
2060 for (i
= 0; i
< disks
; i
++) {
2061 wbio
= r1_bio
->bios
[i
];
2062 if (wbio
->bi_end_io
== NULL
||
2063 (wbio
->bi_end_io
== end_sync_read
&&
2064 (i
== r1_bio
->read_disk
||
2065 !test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
))))
2068 wbio
->bi_rw
= WRITE
;
2069 wbio
->bi_end_io
= end_sync_write
;
2070 atomic_inc(&r1_bio
->remaining
);
2071 md_sync_acct(conf
->mirrors
[i
].rdev
->bdev
, bio_sectors(wbio
));
2073 generic_make_request(wbio
);
2076 if (atomic_dec_and_test(&r1_bio
->remaining
)) {
2077 /* if we're here, all write(s) have completed, so clean up */
2078 int s
= r1_bio
->sectors
;
2079 if (test_bit(R1BIO_MadeGood
, &r1_bio
->state
) ||
2080 test_bit(R1BIO_WriteError
, &r1_bio
->state
))
2081 reschedule_retry(r1_bio
);
2084 md_done_sync(mddev
, s
, 1);
2090 * This is a kernel thread which:
2092 * 1. Retries failed read operations on working mirrors.
2093 * 2. Updates the raid superblock when problems encounter.
2094 * 3. Performs writes following reads for array synchronising.
2097 static void fix_read_error(struct r1conf
*conf
, int read_disk
,
2098 sector_t sect
, int sectors
)
2100 struct mddev
*mddev
= conf
->mddev
;
2106 struct md_rdev
*rdev
;
2108 if (s
> (PAGE_SIZE
>>9))
2112 /* Note: no rcu protection needed here
2113 * as this is synchronous in the raid1d thread
2114 * which is the thread that might remove
2115 * a device. If raid1d ever becomes multi-threaded....
2120 rdev
= conf
->mirrors
[d
].rdev
;
2122 (test_bit(In_sync
, &rdev
->flags
) ||
2123 (!test_bit(Faulty
, &rdev
->flags
) &&
2124 rdev
->recovery_offset
>= sect
+ s
)) &&
2125 is_badblock(rdev
, sect
, s
,
2126 &first_bad
, &bad_sectors
) == 0 &&
2127 sync_page_io(rdev
, sect
, s
<<9,
2128 conf
->tmppage
, READ
, false))
2132 if (d
== conf
->raid_disks
* 2)
2135 } while (!success
&& d
!= read_disk
);
2138 /* Cannot read from anywhere - mark it bad */
2139 struct md_rdev
*rdev
= conf
->mirrors
[read_disk
].rdev
;
2140 if (!rdev_set_badblocks(rdev
, sect
, s
, 0))
2141 md_error(mddev
, rdev
);
2144 /* write it back and re-read */
2146 while (d
!= read_disk
) {
2148 d
= conf
->raid_disks
* 2;
2150 rdev
= conf
->mirrors
[d
].rdev
;
2152 !test_bit(Faulty
, &rdev
->flags
))
2153 r1_sync_page_io(rdev
, sect
, s
,
2154 conf
->tmppage
, WRITE
);
2157 while (d
!= read_disk
) {
2158 char b
[BDEVNAME_SIZE
];
2160 d
= conf
->raid_disks
* 2;
2162 rdev
= conf
->mirrors
[d
].rdev
;
2164 !test_bit(Faulty
, &rdev
->flags
)) {
2165 if (r1_sync_page_io(rdev
, sect
, s
,
2166 conf
->tmppage
, READ
)) {
2167 atomic_add(s
, &rdev
->corrected_errors
);
2169 "md/raid1:%s: read error corrected "
2170 "(%d sectors at %llu on %s)\n",
2172 (unsigned long long)(sect
+
2174 bdevname(rdev
->bdev
, b
));
2183 static int narrow_write_error(struct r1bio
*r1_bio
, int i
)
2185 struct mddev
*mddev
= r1_bio
->mddev
;
2186 struct r1conf
*conf
= mddev
->private;
2187 struct md_rdev
*rdev
= conf
->mirrors
[i
].rdev
;
2189 /* bio has the data to be written to device 'i' where
2190 * we just recently had a write error.
2191 * We repeatedly clone the bio and trim down to one block,
2192 * then try the write. Where the write fails we record
2194 * It is conceivable that the bio doesn't exactly align with
2195 * blocks. We must handle this somehow.
2197 * We currently own a reference on the rdev.
2203 int sect_to_write
= r1_bio
->sectors
;
2206 if (rdev
->badblocks
.shift
< 0)
2209 block_sectors
= 1 << rdev
->badblocks
.shift
;
2210 sector
= r1_bio
->sector
;
2211 sectors
= ((sector
+ block_sectors
)
2212 & ~(sector_t
)(block_sectors
- 1))
2215 while (sect_to_write
) {
2217 if (sectors
> sect_to_write
)
2218 sectors
= sect_to_write
;
2219 /* Write at 'sector' for 'sectors'*/
2221 if (test_bit(R1BIO_BehindIO
, &r1_bio
->state
)) {
2222 unsigned vcnt
= r1_bio
->behind_page_count
;
2223 struct bio_vec
*vec
= r1_bio
->behind_bvecs
;
2225 while (!vec
->bv_page
) {
2230 wbio
= bio_alloc_mddev(GFP_NOIO
, vcnt
, mddev
);
2231 memcpy(wbio
->bi_io_vec
, vec
, vcnt
* sizeof(struct bio_vec
));
2233 wbio
->bi_vcnt
= vcnt
;
2235 wbio
= bio_clone_mddev(r1_bio
->master_bio
, GFP_NOIO
, mddev
);
2238 wbio
->bi_rw
= WRITE
;
2239 wbio
->bi_iter
.bi_sector
= r1_bio
->sector
;
2240 wbio
->bi_iter
.bi_size
= r1_bio
->sectors
<< 9;
2242 bio_trim(wbio
, sector
- r1_bio
->sector
, sectors
);
2243 wbio
->bi_iter
.bi_sector
+= rdev
->data_offset
;
2244 wbio
->bi_bdev
= rdev
->bdev
;
2245 if (submit_bio_wait(WRITE
, wbio
) == 0)
2247 ok
= rdev_set_badblocks(rdev
, sector
,
2252 sect_to_write
-= sectors
;
2254 sectors
= block_sectors
;
2259 static void handle_sync_write_finished(struct r1conf
*conf
, struct r1bio
*r1_bio
)
2262 int s
= r1_bio
->sectors
;
2263 for (m
= 0; m
< conf
->raid_disks
* 2 ; m
++) {
2264 struct md_rdev
*rdev
= conf
->mirrors
[m
].rdev
;
2265 struct bio
*bio
= r1_bio
->bios
[m
];
2266 if (bio
->bi_end_io
== NULL
)
2268 if (test_bit(BIO_UPTODATE
, &bio
->bi_flags
) &&
2269 test_bit(R1BIO_MadeGood
, &r1_bio
->state
)) {
2270 rdev_clear_badblocks(rdev
, r1_bio
->sector
, s
, 0);
2272 if (!test_bit(BIO_UPTODATE
, &bio
->bi_flags
) &&
2273 test_bit(R1BIO_WriteError
, &r1_bio
->state
)) {
2274 if (!rdev_set_badblocks(rdev
, r1_bio
->sector
, s
, 0))
2275 md_error(conf
->mddev
, rdev
);
2279 md_done_sync(conf
->mddev
, s
, 1);
2282 static void handle_write_finished(struct r1conf
*conf
, struct r1bio
*r1_bio
)
2285 for (m
= 0; m
< conf
->raid_disks
* 2 ; m
++)
2286 if (r1_bio
->bios
[m
] == IO_MADE_GOOD
) {
2287 struct md_rdev
*rdev
= conf
->mirrors
[m
].rdev
;
2288 rdev_clear_badblocks(rdev
,
2290 r1_bio
->sectors
, 0);
2291 rdev_dec_pending(rdev
, conf
->mddev
);
2292 } else if (r1_bio
->bios
[m
] != NULL
) {
2293 /* This drive got a write error. We need to
2294 * narrow down and record precise write
2297 if (!narrow_write_error(r1_bio
, m
)) {
2298 md_error(conf
->mddev
,
2299 conf
->mirrors
[m
].rdev
);
2300 /* an I/O failed, we can't clear the bitmap */
2301 set_bit(R1BIO_Degraded
, &r1_bio
->state
);
2303 rdev_dec_pending(conf
->mirrors
[m
].rdev
,
2306 if (test_bit(R1BIO_WriteError
, &r1_bio
->state
))
2307 close_write(r1_bio
);
2308 raid_end_bio_io(r1_bio
);
2311 static void handle_read_error(struct r1conf
*conf
, struct r1bio
*r1_bio
)
2315 struct mddev
*mddev
= conf
->mddev
;
2317 char b
[BDEVNAME_SIZE
];
2318 struct md_rdev
*rdev
;
2320 clear_bit(R1BIO_ReadError
, &r1_bio
->state
);
2321 /* we got a read error. Maybe the drive is bad. Maybe just
2322 * the block and we can fix it.
2323 * We freeze all other IO, and try reading the block from
2324 * other devices. When we find one, we re-write
2325 * and check it that fixes the read error.
2326 * This is all done synchronously while the array is
2329 if (mddev
->ro
== 0) {
2330 freeze_array(conf
, 1);
2331 fix_read_error(conf
, r1_bio
->read_disk
,
2332 r1_bio
->sector
, r1_bio
->sectors
);
2333 unfreeze_array(conf
);
2335 md_error(mddev
, conf
->mirrors
[r1_bio
->read_disk
].rdev
);
2336 rdev_dec_pending(conf
->mirrors
[r1_bio
->read_disk
].rdev
, conf
->mddev
);
2338 bio
= r1_bio
->bios
[r1_bio
->read_disk
];
2339 bdevname(bio
->bi_bdev
, b
);
2341 disk
= read_balance(conf
, r1_bio
, &max_sectors
);
2343 printk(KERN_ALERT
"md/raid1:%s: %s: unrecoverable I/O"
2344 " read error for block %llu\n",
2345 mdname(mddev
), b
, (unsigned long long)r1_bio
->sector
);
2346 raid_end_bio_io(r1_bio
);
2348 const unsigned long do_sync
2349 = r1_bio
->master_bio
->bi_rw
& REQ_SYNC
;
2351 r1_bio
->bios
[r1_bio
->read_disk
] =
2352 mddev
->ro
? IO_BLOCKED
: NULL
;
2355 r1_bio
->read_disk
= disk
;
2356 bio
= bio_clone_mddev(r1_bio
->master_bio
, GFP_NOIO
, mddev
);
2357 bio_trim(bio
, r1_bio
->sector
- bio
->bi_iter
.bi_sector
,
2359 r1_bio
->bios
[r1_bio
->read_disk
] = bio
;
2360 rdev
= conf
->mirrors
[disk
].rdev
;
2361 printk_ratelimited(KERN_ERR
2362 "md/raid1:%s: redirecting sector %llu"
2363 " to other mirror: %s\n",
2365 (unsigned long long)r1_bio
->sector
,
2366 bdevname(rdev
->bdev
, b
));
2367 bio
->bi_iter
.bi_sector
= r1_bio
->sector
+ rdev
->data_offset
;
2368 bio
->bi_bdev
= rdev
->bdev
;
2369 bio
->bi_end_io
= raid1_end_read_request
;
2370 bio
->bi_rw
= READ
| do_sync
;
2371 bio
->bi_private
= r1_bio
;
2372 if (max_sectors
< r1_bio
->sectors
) {
2373 /* Drat - have to split this up more */
2374 struct bio
*mbio
= r1_bio
->master_bio
;
2375 int sectors_handled
= (r1_bio
->sector
+ max_sectors
2376 - mbio
->bi_iter
.bi_sector
);
2377 r1_bio
->sectors
= max_sectors
;
2378 spin_lock_irq(&conf
->device_lock
);
2379 if (mbio
->bi_phys_segments
== 0)
2380 mbio
->bi_phys_segments
= 2;
2382 mbio
->bi_phys_segments
++;
2383 spin_unlock_irq(&conf
->device_lock
);
2384 generic_make_request(bio
);
2387 r1_bio
= mempool_alloc(conf
->r1bio_pool
, GFP_NOIO
);
2389 r1_bio
->master_bio
= mbio
;
2390 r1_bio
->sectors
= bio_sectors(mbio
) - sectors_handled
;
2392 set_bit(R1BIO_ReadError
, &r1_bio
->state
);
2393 r1_bio
->mddev
= mddev
;
2394 r1_bio
->sector
= mbio
->bi_iter
.bi_sector
+
2399 generic_make_request(bio
);
2403 static void raid1d(struct md_thread
*thread
)
2405 struct mddev
*mddev
= thread
->mddev
;
2406 struct r1bio
*r1_bio
;
2407 unsigned long flags
;
2408 struct r1conf
*conf
= mddev
->private;
2409 struct list_head
*head
= &conf
->retry_list
;
2410 struct blk_plug plug
;
2412 md_check_recovery(mddev
);
2414 blk_start_plug(&plug
);
2417 flush_pending_writes(conf
);
2419 spin_lock_irqsave(&conf
->device_lock
, flags
);
2420 if (list_empty(head
)) {
2421 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
2424 r1_bio
= list_entry(head
->prev
, struct r1bio
, retry_list
);
2425 list_del(head
->prev
);
2427 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
2429 mddev
= r1_bio
->mddev
;
2430 conf
= mddev
->private;
2431 if (test_bit(R1BIO_IsSync
, &r1_bio
->state
)) {
2432 if (test_bit(R1BIO_MadeGood
, &r1_bio
->state
) ||
2433 test_bit(R1BIO_WriteError
, &r1_bio
->state
))
2434 handle_sync_write_finished(conf
, r1_bio
);
2436 sync_request_write(mddev
, r1_bio
);
2437 } else if (test_bit(R1BIO_MadeGood
, &r1_bio
->state
) ||
2438 test_bit(R1BIO_WriteError
, &r1_bio
->state
))
2439 handle_write_finished(conf
, r1_bio
);
2440 else if (test_bit(R1BIO_ReadError
, &r1_bio
->state
))
2441 handle_read_error(conf
, r1_bio
);
2443 /* just a partial read to be scheduled from separate
2446 generic_make_request(r1_bio
->bios
[r1_bio
->read_disk
]);
2449 if (mddev
->flags
& ~(1<<MD_CHANGE_PENDING
))
2450 md_check_recovery(mddev
);
2452 blk_finish_plug(&plug
);
2455 static int init_resync(struct r1conf
*conf
)
2459 buffs
= RESYNC_WINDOW
/ RESYNC_BLOCK_SIZE
;
2460 BUG_ON(conf
->r1buf_pool
);
2461 conf
->r1buf_pool
= mempool_create(buffs
, r1buf_pool_alloc
, r1buf_pool_free
,
2463 if (!conf
->r1buf_pool
)
2465 conf
->next_resync
= 0;
2470 * perform a "sync" on one "block"
2472 * We need to make sure that no normal I/O request - particularly write
2473 * requests - conflict with active sync requests.
2475 * This is achieved by tracking pending requests and a 'barrier' concept
2476 * that can be installed to exclude normal IO requests.
2479 static sector_t
sync_request(struct mddev
*mddev
, sector_t sector_nr
, int *skipped
, int go_faster
)
2481 struct r1conf
*conf
= mddev
->private;
2482 struct r1bio
*r1_bio
;
2484 sector_t max_sector
, nr_sectors
;
2488 int write_targets
= 0, read_targets
= 0;
2489 sector_t sync_blocks
;
2490 int still_degraded
= 0;
2491 int good_sectors
= RESYNC_SECTORS
;
2492 int min_bad
= 0; /* number of sectors that are bad in all devices */
2494 if (!conf
->r1buf_pool
)
2495 if (init_resync(conf
))
2498 max_sector
= mddev
->dev_sectors
;
2499 if (sector_nr
>= max_sector
) {
2500 /* If we aborted, we need to abort the
2501 * sync on the 'current' bitmap chunk (there will
2502 * only be one in raid1 resync.
2503 * We can find the current addess in mddev->curr_resync
2505 if (mddev
->curr_resync
< max_sector
) /* aborted */
2506 bitmap_end_sync(mddev
->bitmap
, mddev
->curr_resync
,
2508 else /* completed sync */
2511 bitmap_close_sync(mddev
->bitmap
);
2516 if (mddev
->bitmap
== NULL
&&
2517 mddev
->recovery_cp
== MaxSector
&&
2518 !test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
) &&
2519 conf
->fullsync
== 0) {
2521 return max_sector
- sector_nr
;
2523 /* before building a request, check if we can skip these blocks..
2524 * This call the bitmap_start_sync doesn't actually record anything
2526 if (!bitmap_start_sync(mddev
->bitmap
, sector_nr
, &sync_blocks
, 1) &&
2527 !conf
->fullsync
&& !test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
)) {
2528 /* We can skip this block, and probably several more */
2533 * If there is non-resync activity waiting for a turn,
2534 * and resync is going fast enough,
2535 * then let it though before starting on this new sync request.
2537 if (!go_faster
&& conf
->nr_waiting
)
2538 msleep_interruptible(1000);
2540 bitmap_cond_end_sync(mddev
->bitmap
, sector_nr
);
2541 r1_bio
= mempool_alloc(conf
->r1buf_pool
, GFP_NOIO
);
2543 raise_barrier(conf
, sector_nr
);
2547 * If we get a correctably read error during resync or recovery,
2548 * we might want to read from a different device. So we
2549 * flag all drives that could conceivably be read from for READ,
2550 * and any others (which will be non-In_sync devices) for WRITE.
2551 * If a read fails, we try reading from something else for which READ
2555 r1_bio
->mddev
= mddev
;
2556 r1_bio
->sector
= sector_nr
;
2558 set_bit(R1BIO_IsSync
, &r1_bio
->state
);
2560 for (i
= 0; i
< conf
->raid_disks
* 2; i
++) {
2561 struct md_rdev
*rdev
;
2562 bio
= r1_bio
->bios
[i
];
2565 rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
2567 test_bit(Faulty
, &rdev
->flags
)) {
2568 if (i
< conf
->raid_disks
)
2570 } else if (!test_bit(In_sync
, &rdev
->flags
)) {
2572 bio
->bi_end_io
= end_sync_write
;
2575 /* may need to read from here */
2576 sector_t first_bad
= MaxSector
;
2579 if (is_badblock(rdev
, sector_nr
, good_sectors
,
2580 &first_bad
, &bad_sectors
)) {
2581 if (first_bad
> sector_nr
)
2582 good_sectors
= first_bad
- sector_nr
;
2584 bad_sectors
-= (sector_nr
- first_bad
);
2586 min_bad
> bad_sectors
)
2587 min_bad
= bad_sectors
;
2590 if (sector_nr
< first_bad
) {
2591 if (test_bit(WriteMostly
, &rdev
->flags
)) {
2599 bio
->bi_end_io
= end_sync_read
;
2601 } else if (!test_bit(WriteErrorSeen
, &rdev
->flags
) &&
2602 test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
) &&
2603 !test_bit(MD_RECOVERY_CHECK
, &mddev
->recovery
)) {
2605 * The device is suitable for reading (InSync),
2606 * but has bad block(s) here. Let's try to correct them,
2607 * if we are doing resync or repair. Otherwise, leave
2608 * this device alone for this sync request.
2611 bio
->bi_end_io
= end_sync_write
;
2615 if (bio
->bi_end_io
) {
2616 atomic_inc(&rdev
->nr_pending
);
2617 bio
->bi_iter
.bi_sector
= sector_nr
+ rdev
->data_offset
;
2618 bio
->bi_bdev
= rdev
->bdev
;
2619 bio
->bi_private
= r1_bio
;
2625 r1_bio
->read_disk
= disk
;
2627 if (read_targets
== 0 && min_bad
> 0) {
2628 /* These sectors are bad on all InSync devices, so we
2629 * need to mark them bad on all write targets
2632 for (i
= 0 ; i
< conf
->raid_disks
* 2 ; i
++)
2633 if (r1_bio
->bios
[i
]->bi_end_io
== end_sync_write
) {
2634 struct md_rdev
*rdev
= conf
->mirrors
[i
].rdev
;
2635 ok
= rdev_set_badblocks(rdev
, sector_nr
,
2639 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
2644 /* Cannot record the badblocks, so need to
2646 * If there are multiple read targets, could just
2647 * fail the really bad ones ???
2649 conf
->recovery_disabled
= mddev
->recovery_disabled
;
2650 set_bit(MD_RECOVERY_INTR
, &mddev
->recovery
);
2656 if (min_bad
> 0 && min_bad
< good_sectors
) {
2657 /* only resync enough to reach the next bad->good
2659 good_sectors
= min_bad
;
2662 if (test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
) && read_targets
> 0)
2663 /* extra read targets are also write targets */
2664 write_targets
+= read_targets
-1;
2666 if (write_targets
== 0 || read_targets
== 0) {
2667 /* There is nowhere to write, so all non-sync
2668 * drives must be failed - so we are finished
2672 max_sector
= sector_nr
+ min_bad
;
2673 rv
= max_sector
- sector_nr
;
2679 if (max_sector
> mddev
->resync_max
)
2680 max_sector
= mddev
->resync_max
; /* Don't do IO beyond here */
2681 if (max_sector
> sector_nr
+ good_sectors
)
2682 max_sector
= sector_nr
+ good_sectors
;
2687 int len
= PAGE_SIZE
;
2688 if (sector_nr
+ (len
>>9) > max_sector
)
2689 len
= (max_sector
- sector_nr
) << 9;
2692 if (sync_blocks
== 0) {
2693 if (!bitmap_start_sync(mddev
->bitmap
, sector_nr
,
2694 &sync_blocks
, still_degraded
) &&
2696 !test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
))
2698 BUG_ON(sync_blocks
< (PAGE_SIZE
>>9));
2699 if ((len
>> 9) > sync_blocks
)
2700 len
= sync_blocks
<<9;
2703 for (i
= 0 ; i
< conf
->raid_disks
* 2; i
++) {
2704 bio
= r1_bio
->bios
[i
];
2705 if (bio
->bi_end_io
) {
2706 page
= bio
->bi_io_vec
[bio
->bi_vcnt
].bv_page
;
2707 if (bio_add_page(bio
, page
, len
, 0) == 0) {
2709 bio
->bi_io_vec
[bio
->bi_vcnt
].bv_page
= page
;
2712 bio
= r1_bio
->bios
[i
];
2713 if (bio
->bi_end_io
==NULL
)
2715 /* remove last page from this bio */
2717 bio
->bi_iter
.bi_size
-= len
;
2718 __clear_bit(BIO_SEG_VALID
, &bio
->bi_flags
);
2724 nr_sectors
+= len
>>9;
2725 sector_nr
+= len
>>9;
2726 sync_blocks
-= (len
>>9);
2727 } while (r1_bio
->bios
[disk
]->bi_vcnt
< RESYNC_PAGES
);
2729 r1_bio
->sectors
= nr_sectors
;
2731 /* For a user-requested sync, we read all readable devices and do a
2734 if (test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
)) {
2735 atomic_set(&r1_bio
->remaining
, read_targets
);
2736 for (i
= 0; i
< conf
->raid_disks
* 2 && read_targets
; i
++) {
2737 bio
= r1_bio
->bios
[i
];
2738 if (bio
->bi_end_io
== end_sync_read
) {
2740 md_sync_acct(bio
->bi_bdev
, nr_sectors
);
2741 generic_make_request(bio
);
2745 atomic_set(&r1_bio
->remaining
, 1);
2746 bio
= r1_bio
->bios
[r1_bio
->read_disk
];
2747 md_sync_acct(bio
->bi_bdev
, nr_sectors
);
2748 generic_make_request(bio
);
2754 static sector_t
raid1_size(struct mddev
*mddev
, sector_t sectors
, int raid_disks
)
2759 return mddev
->dev_sectors
;
2762 static struct r1conf
*setup_conf(struct mddev
*mddev
)
2764 struct r1conf
*conf
;
2766 struct raid1_info
*disk
;
2767 struct md_rdev
*rdev
;
2770 conf
= kzalloc(sizeof(struct r1conf
), GFP_KERNEL
);
2774 conf
->mirrors
= kzalloc(sizeof(struct raid1_info
)
2775 * mddev
->raid_disks
* 2,
2780 conf
->tmppage
= alloc_page(GFP_KERNEL
);
2784 conf
->poolinfo
= kzalloc(sizeof(*conf
->poolinfo
), GFP_KERNEL
);
2785 if (!conf
->poolinfo
)
2787 conf
->poolinfo
->raid_disks
= mddev
->raid_disks
* 2;
2788 conf
->r1bio_pool
= mempool_create(NR_RAID1_BIOS
, r1bio_pool_alloc
,
2791 if (!conf
->r1bio_pool
)
2794 conf
->poolinfo
->mddev
= mddev
;
2797 spin_lock_init(&conf
->device_lock
);
2798 rdev_for_each(rdev
, mddev
) {
2799 struct request_queue
*q
;
2800 int disk_idx
= rdev
->raid_disk
;
2801 if (disk_idx
>= mddev
->raid_disks
2804 if (test_bit(Replacement
, &rdev
->flags
))
2805 disk
= conf
->mirrors
+ mddev
->raid_disks
+ disk_idx
;
2807 disk
= conf
->mirrors
+ disk_idx
;
2812 q
= bdev_get_queue(rdev
->bdev
);
2813 if (q
->merge_bvec_fn
)
2814 mddev
->merge_check_needed
= 1;
2816 disk
->head_position
= 0;
2817 disk
->seq_start
= MaxSector
;
2819 conf
->raid_disks
= mddev
->raid_disks
;
2820 conf
->mddev
= mddev
;
2821 INIT_LIST_HEAD(&conf
->retry_list
);
2823 spin_lock_init(&conf
->resync_lock
);
2824 init_waitqueue_head(&conf
->wait_barrier
);
2826 bio_list_init(&conf
->pending_bio_list
);
2827 conf
->pending_count
= 0;
2828 conf
->recovery_disabled
= mddev
->recovery_disabled
- 1;
2830 conf
->start_next_window
= MaxSector
;
2831 conf
->current_window_requests
= conf
->next_window_requests
= 0;
2834 for (i
= 0; i
< conf
->raid_disks
* 2; i
++) {
2836 disk
= conf
->mirrors
+ i
;
2838 if (i
< conf
->raid_disks
&&
2839 disk
[conf
->raid_disks
].rdev
) {
2840 /* This slot has a replacement. */
2842 /* No original, just make the replacement
2843 * a recovering spare
2846 disk
[conf
->raid_disks
].rdev
;
2847 disk
[conf
->raid_disks
].rdev
= NULL
;
2848 } else if (!test_bit(In_sync
, &disk
->rdev
->flags
))
2849 /* Original is not in_sync - bad */
2854 !test_bit(In_sync
, &disk
->rdev
->flags
)) {
2855 disk
->head_position
= 0;
2857 (disk
->rdev
->saved_raid_disk
< 0))
2863 conf
->thread
= md_register_thread(raid1d
, mddev
, "raid1");
2864 if (!conf
->thread
) {
2866 "md/raid1:%s: couldn't allocate thread\n",
2875 if (conf
->r1bio_pool
)
2876 mempool_destroy(conf
->r1bio_pool
);
2877 kfree(conf
->mirrors
);
2878 safe_put_page(conf
->tmppage
);
2879 kfree(conf
->poolinfo
);
2882 return ERR_PTR(err
);
2885 static int stop(struct mddev
*mddev
);
2886 static int run(struct mddev
*mddev
)
2888 struct r1conf
*conf
;
2890 struct md_rdev
*rdev
;
2892 bool discard_supported
= false;
2894 if (mddev
->level
!= 1) {
2895 printk(KERN_ERR
"md/raid1:%s: raid level not set to mirroring (%d)\n",
2896 mdname(mddev
), mddev
->level
);
2899 if (mddev
->reshape_position
!= MaxSector
) {
2900 printk(KERN_ERR
"md/raid1:%s: reshape_position set but not supported\n",
2905 * copy the already verified devices into our private RAID1
2906 * bookkeeping area. [whatever we allocate in run(),
2907 * should be freed in stop()]
2909 if (mddev
->private == NULL
)
2910 conf
= setup_conf(mddev
);
2912 conf
= mddev
->private;
2915 return PTR_ERR(conf
);
2918 blk_queue_max_write_same_sectors(mddev
->queue
, 0);
2920 rdev_for_each(rdev
, mddev
) {
2921 if (!mddev
->gendisk
)
2923 disk_stack_limits(mddev
->gendisk
, rdev
->bdev
,
2924 rdev
->data_offset
<< 9);
2925 if (blk_queue_discard(bdev_get_queue(rdev
->bdev
)))
2926 discard_supported
= true;
2929 mddev
->degraded
= 0;
2930 for (i
=0; i
< conf
->raid_disks
; i
++)
2931 if (conf
->mirrors
[i
].rdev
== NULL
||
2932 !test_bit(In_sync
, &conf
->mirrors
[i
].rdev
->flags
) ||
2933 test_bit(Faulty
, &conf
->mirrors
[i
].rdev
->flags
))
2936 if (conf
->raid_disks
- mddev
->degraded
== 1)
2937 mddev
->recovery_cp
= MaxSector
;
2939 if (mddev
->recovery_cp
!= MaxSector
)
2940 printk(KERN_NOTICE
"md/raid1:%s: not clean"
2941 " -- starting background reconstruction\n",
2944 "md/raid1:%s: active with %d out of %d mirrors\n",
2945 mdname(mddev
), mddev
->raid_disks
- mddev
->degraded
,
2949 * Ok, everything is just fine now
2951 mddev
->thread
= conf
->thread
;
2952 conf
->thread
= NULL
;
2953 mddev
->private = conf
;
2955 md_set_array_sectors(mddev
, raid1_size(mddev
, 0, 0));
2958 mddev
->queue
->backing_dev_info
.congested_fn
= raid1_congested
;
2959 mddev
->queue
->backing_dev_info
.congested_data
= mddev
;
2960 blk_queue_merge_bvec(mddev
->queue
, raid1_mergeable_bvec
);
2962 if (discard_supported
)
2963 queue_flag_set_unlocked(QUEUE_FLAG_DISCARD
,
2966 queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD
,
2970 ret
= md_integrity_register(mddev
);
2976 static int stop(struct mddev
*mddev
)
2978 struct r1conf
*conf
= mddev
->private;
2979 struct bitmap
*bitmap
= mddev
->bitmap
;
2981 /* wait for behind writes to complete */
2982 if (bitmap
&& atomic_read(&bitmap
->behind_writes
) > 0) {
2983 printk(KERN_INFO
"md/raid1:%s: behind writes in progress - waiting to stop.\n",
2985 /* need to kick something here to make sure I/O goes? */
2986 wait_event(bitmap
->behind_wait
,
2987 atomic_read(&bitmap
->behind_writes
) == 0);
2990 freeze_array(conf
, 0);
2991 unfreeze_array(conf
);
2993 md_unregister_thread(&mddev
->thread
);
2994 if (conf
->r1bio_pool
)
2995 mempool_destroy(conf
->r1bio_pool
);
2996 kfree(conf
->mirrors
);
2997 safe_put_page(conf
->tmppage
);
2998 kfree(conf
->poolinfo
);
3000 mddev
->private = NULL
;
3004 static int raid1_resize(struct mddev
*mddev
, sector_t sectors
)
3006 /* no resync is happening, and there is enough space
3007 * on all devices, so we can resize.
3008 * We need to make sure resync covers any new space.
3009 * If the array is shrinking we should possibly wait until
3010 * any io in the removed space completes, but it hardly seems
3013 sector_t newsize
= raid1_size(mddev
, sectors
, 0);
3014 if (mddev
->external_size
&&
3015 mddev
->array_sectors
> newsize
)
3017 if (mddev
->bitmap
) {
3018 int ret
= bitmap_resize(mddev
->bitmap
, newsize
, 0, 0);
3022 md_set_array_sectors(mddev
, newsize
);
3023 set_capacity(mddev
->gendisk
, mddev
->array_sectors
);
3024 revalidate_disk(mddev
->gendisk
);
3025 if (sectors
> mddev
->dev_sectors
&&
3026 mddev
->recovery_cp
> mddev
->dev_sectors
) {
3027 mddev
->recovery_cp
= mddev
->dev_sectors
;
3028 set_bit(MD_RECOVERY_NEEDED
, &mddev
->recovery
);
3030 mddev
->dev_sectors
= sectors
;
3031 mddev
->resync_max_sectors
= sectors
;
3035 static int raid1_reshape(struct mddev
*mddev
)
3038 * 1/ resize the r1bio_pool
3039 * 2/ resize conf->mirrors
3041 * We allocate a new r1bio_pool if we can.
3042 * Then raise a device barrier and wait until all IO stops.
3043 * Then resize conf->mirrors and swap in the new r1bio pool.
3045 * At the same time, we "pack" the devices so that all the missing
3046 * devices have the higher raid_disk numbers.
3048 mempool_t
*newpool
, *oldpool
;
3049 struct pool_info
*newpoolinfo
;
3050 struct raid1_info
*newmirrors
;
3051 struct r1conf
*conf
= mddev
->private;
3052 int cnt
, raid_disks
;
3053 unsigned long flags
;
3056 /* Cannot change chunk_size, layout, or level */
3057 if (mddev
->chunk_sectors
!= mddev
->new_chunk_sectors
||
3058 mddev
->layout
!= mddev
->new_layout
||
3059 mddev
->level
!= mddev
->new_level
) {
3060 mddev
->new_chunk_sectors
= mddev
->chunk_sectors
;
3061 mddev
->new_layout
= mddev
->layout
;
3062 mddev
->new_level
= mddev
->level
;
3066 err
= md_allow_write(mddev
);
3070 raid_disks
= mddev
->raid_disks
+ mddev
->delta_disks
;
3072 if (raid_disks
< conf
->raid_disks
) {
3074 for (d
= 0; d
< conf
->raid_disks
; d
++)
3075 if (conf
->mirrors
[d
].rdev
)
3077 if (cnt
> raid_disks
)
3081 newpoolinfo
= kmalloc(sizeof(*newpoolinfo
), GFP_KERNEL
);
3084 newpoolinfo
->mddev
= mddev
;
3085 newpoolinfo
->raid_disks
= raid_disks
* 2;
3087 newpool
= mempool_create(NR_RAID1_BIOS
, r1bio_pool_alloc
,
3088 r1bio_pool_free
, newpoolinfo
);
3093 newmirrors
= kzalloc(sizeof(struct raid1_info
) * raid_disks
* 2,
3097 mempool_destroy(newpool
);
3101 freeze_array(conf
, 0);
3103 /* ok, everything is stopped */
3104 oldpool
= conf
->r1bio_pool
;
3105 conf
->r1bio_pool
= newpool
;
3107 for (d
= d2
= 0; d
< conf
->raid_disks
; d
++) {
3108 struct md_rdev
*rdev
= conf
->mirrors
[d
].rdev
;
3109 if (rdev
&& rdev
->raid_disk
!= d2
) {
3110 sysfs_unlink_rdev(mddev
, rdev
);
3111 rdev
->raid_disk
= d2
;
3112 sysfs_unlink_rdev(mddev
, rdev
);
3113 if (sysfs_link_rdev(mddev
, rdev
))
3115 "md/raid1:%s: cannot register rd%d\n",
3116 mdname(mddev
), rdev
->raid_disk
);
3119 newmirrors
[d2
++].rdev
= rdev
;
3121 kfree(conf
->mirrors
);
3122 conf
->mirrors
= newmirrors
;
3123 kfree(conf
->poolinfo
);
3124 conf
->poolinfo
= newpoolinfo
;
3126 spin_lock_irqsave(&conf
->device_lock
, flags
);
3127 mddev
->degraded
+= (raid_disks
- conf
->raid_disks
);
3128 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
3129 conf
->raid_disks
= mddev
->raid_disks
= raid_disks
;
3130 mddev
->delta_disks
= 0;
3132 unfreeze_array(conf
);
3134 set_bit(MD_RECOVERY_NEEDED
, &mddev
->recovery
);
3135 md_wakeup_thread(mddev
->thread
);
3137 mempool_destroy(oldpool
);
3141 static void raid1_quiesce(struct mddev
*mddev
, int state
)
3143 struct r1conf
*conf
= mddev
->private;
3146 case 2: /* wake for suspend */
3147 wake_up(&conf
->wait_barrier
);
3150 freeze_array(conf
, 0);
3153 unfreeze_array(conf
);
3158 static void *raid1_takeover(struct mddev
*mddev
)
3160 /* raid1 can take over:
3161 * raid5 with 2 devices, any layout or chunk size
3163 if (mddev
->level
== 5 && mddev
->raid_disks
== 2) {
3164 struct r1conf
*conf
;
3165 mddev
->new_level
= 1;
3166 mddev
->new_layout
= 0;
3167 mddev
->new_chunk_sectors
= 0;
3168 conf
= setup_conf(mddev
);
3170 /* Array must appear to be quiesced */
3171 conf
->array_frozen
= 1;
3174 return ERR_PTR(-EINVAL
);
3177 static struct md_personality raid1_personality
=
3181 .owner
= THIS_MODULE
,
3182 .make_request
= make_request
,
3186 .error_handler
= error
,
3187 .hot_add_disk
= raid1_add_disk
,
3188 .hot_remove_disk
= raid1_remove_disk
,
3189 .spare_active
= raid1_spare_active
,
3190 .sync_request
= sync_request
,
3191 .resize
= raid1_resize
,
3193 .check_reshape
= raid1_reshape
,
3194 .quiesce
= raid1_quiesce
,
3195 .takeover
= raid1_takeover
,
3198 static int __init
raid_init(void)
3200 return register_md_personality(&raid1_personality
);
3203 static void raid_exit(void)
3205 unregister_md_personality(&raid1_personality
);
3208 module_init(raid_init
);
3209 module_exit(raid_exit
);
3210 MODULE_LICENSE("GPL");
3211 MODULE_DESCRIPTION("RAID1 (mirroring) personality for MD");
3212 MODULE_ALIAS("md-personality-3"); /* RAID1 */
3213 MODULE_ALIAS("md-raid1");
3214 MODULE_ALIAS("md-level-1");
3216 module_param(max_queued_requests
, int, S_IRUGO
|S_IWUSR
);