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
;
102 r1_bio
= r1bio_pool_alloc(gfp_flags
, pi
);
107 * Allocate bios : 1 for reading, n-1 for writing
109 for (j
= pi
->raid_disks
; j
-- ; ) {
110 bio
= bio_kmalloc(gfp_flags
, RESYNC_PAGES
);
113 r1_bio
->bios
[j
] = bio
;
116 * Allocate RESYNC_PAGES data pages and attach them to
118 * If this is a user-requested check/repair, allocate
119 * RESYNC_PAGES for each bio.
121 if (test_bit(MD_RECOVERY_REQUESTED
, &pi
->mddev
->recovery
))
126 bio
= r1_bio
->bios
[j
];
127 bio
->bi_vcnt
= RESYNC_PAGES
;
129 if (bio_alloc_pages(bio
, gfp_flags
))
132 /* If not user-requests, copy the page pointers to all bios */
133 if (!test_bit(MD_RECOVERY_REQUESTED
, &pi
->mddev
->recovery
)) {
134 for (i
=0; i
<RESYNC_PAGES
; i
++)
135 for (j
=1; j
<pi
->raid_disks
; j
++)
136 r1_bio
->bios
[j
]->bi_io_vec
[i
].bv_page
=
137 r1_bio
->bios
[0]->bi_io_vec
[i
].bv_page
;
140 r1_bio
->master_bio
= NULL
;
145 while (++j
< pi
->raid_disks
)
146 bio_put(r1_bio
->bios
[j
]);
147 r1bio_pool_free(r1_bio
, data
);
151 static void r1buf_pool_free(void *__r1_bio
, void *data
)
153 struct pool_info
*pi
= data
;
155 struct r1bio
*r1bio
= __r1_bio
;
157 for (i
= 0; i
< RESYNC_PAGES
; i
++)
158 for (j
= pi
->raid_disks
; j
-- ;) {
160 r1bio
->bios
[j
]->bi_io_vec
[i
].bv_page
!=
161 r1bio
->bios
[0]->bi_io_vec
[i
].bv_page
)
162 safe_put_page(r1bio
->bios
[j
]->bi_io_vec
[i
].bv_page
);
164 for (i
=0 ; i
< pi
->raid_disks
; i
++)
165 bio_put(r1bio
->bios
[i
]);
167 r1bio_pool_free(r1bio
, data
);
170 static void put_all_bios(struct r1conf
*conf
, struct r1bio
*r1_bio
)
174 for (i
= 0; i
< conf
->raid_disks
* 2; i
++) {
175 struct bio
**bio
= r1_bio
->bios
+ i
;
176 if (!BIO_SPECIAL(*bio
))
182 static void free_r1bio(struct r1bio
*r1_bio
)
184 struct r1conf
*conf
= r1_bio
->mddev
->private;
186 put_all_bios(conf
, r1_bio
);
187 mempool_free(r1_bio
, conf
->r1bio_pool
);
190 static void put_buf(struct r1bio
*r1_bio
)
192 struct r1conf
*conf
= r1_bio
->mddev
->private;
195 for (i
= 0; i
< conf
->raid_disks
* 2; i
++) {
196 struct bio
*bio
= r1_bio
->bios
[i
];
198 rdev_dec_pending(conf
->mirrors
[i
].rdev
, r1_bio
->mddev
);
201 mempool_free(r1_bio
, conf
->r1buf_pool
);
206 static void reschedule_retry(struct r1bio
*r1_bio
)
209 struct mddev
*mddev
= r1_bio
->mddev
;
210 struct r1conf
*conf
= mddev
->private;
212 spin_lock_irqsave(&conf
->device_lock
, flags
);
213 list_add(&r1_bio
->retry_list
, &conf
->retry_list
);
215 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
217 wake_up(&conf
->wait_barrier
);
218 md_wakeup_thread(mddev
->thread
);
222 * raid_end_bio_io() is called when we have finished servicing a mirrored
223 * operation and are ready to return a success/failure code to the buffer
226 static void call_bio_endio(struct r1bio
*r1_bio
)
228 struct bio
*bio
= r1_bio
->master_bio
;
230 struct r1conf
*conf
= r1_bio
->mddev
->private;
231 sector_t start_next_window
= r1_bio
->start_next_window
;
232 sector_t bi_sector
= bio
->bi_sector
;
234 if (bio
->bi_phys_segments
) {
236 spin_lock_irqsave(&conf
->device_lock
, flags
);
237 bio
->bi_phys_segments
--;
238 done
= (bio
->bi_phys_segments
== 0);
239 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
241 * make_request() might be waiting for
242 * bi_phys_segments to decrease
244 wake_up(&conf
->wait_barrier
);
248 if (!test_bit(R1BIO_Uptodate
, &r1_bio
->state
))
249 clear_bit(BIO_UPTODATE
, &bio
->bi_flags
);
253 * Wake up any possible resync thread that waits for the device
256 allow_barrier(conf
, start_next_window
, bi_sector
);
260 static void raid_end_bio_io(struct r1bio
*r1_bio
)
262 struct bio
*bio
= r1_bio
->master_bio
;
264 /* if nobody has done the final endio yet, do it now */
265 if (!test_and_set_bit(R1BIO_Returned
, &r1_bio
->state
)) {
266 pr_debug("raid1: sync end %s on sectors %llu-%llu\n",
267 (bio_data_dir(bio
) == WRITE
) ? "write" : "read",
268 (unsigned long long) bio
->bi_sector
,
269 (unsigned long long) bio
->bi_sector
+
270 bio_sectors(bio
) - 1);
272 call_bio_endio(r1_bio
);
278 * Update disk head position estimator based on IRQ completion info.
280 static inline void update_head_pos(int disk
, struct r1bio
*r1_bio
)
282 struct r1conf
*conf
= r1_bio
->mddev
->private;
284 conf
->mirrors
[disk
].head_position
=
285 r1_bio
->sector
+ (r1_bio
->sectors
);
289 * Find the disk number which triggered given bio
291 static int find_bio_disk(struct r1bio
*r1_bio
, struct bio
*bio
)
294 struct r1conf
*conf
= r1_bio
->mddev
->private;
295 int raid_disks
= conf
->raid_disks
;
297 for (mirror
= 0; mirror
< raid_disks
* 2; mirror
++)
298 if (r1_bio
->bios
[mirror
] == bio
)
301 BUG_ON(mirror
== raid_disks
* 2);
302 update_head_pos(mirror
, r1_bio
);
307 static void raid1_end_read_request(struct bio
*bio
, int error
)
309 int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
310 struct r1bio
*r1_bio
= bio
->bi_private
;
312 struct r1conf
*conf
= r1_bio
->mddev
->private;
314 mirror
= r1_bio
->read_disk
;
316 * this branch is our 'one mirror IO has finished' event handler:
318 update_head_pos(mirror
, r1_bio
);
321 set_bit(R1BIO_Uptodate
, &r1_bio
->state
);
323 /* If all other devices have failed, we want to return
324 * the error upwards rather than fail the last device.
325 * Here we redefine "uptodate" to mean "Don't want to retry"
328 spin_lock_irqsave(&conf
->device_lock
, flags
);
329 if (r1_bio
->mddev
->degraded
== conf
->raid_disks
||
330 (r1_bio
->mddev
->degraded
== conf
->raid_disks
-1 &&
331 !test_bit(Faulty
, &conf
->mirrors
[mirror
].rdev
->flags
)))
333 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
337 raid_end_bio_io(r1_bio
);
338 rdev_dec_pending(conf
->mirrors
[mirror
].rdev
, conf
->mddev
);
343 char b
[BDEVNAME_SIZE
];
345 KERN_ERR
"md/raid1:%s: %s: "
346 "rescheduling sector %llu\n",
348 bdevname(conf
->mirrors
[mirror
].rdev
->bdev
,
350 (unsigned long long)r1_bio
->sector
);
351 set_bit(R1BIO_ReadError
, &r1_bio
->state
);
352 reschedule_retry(r1_bio
);
353 /* don't drop the reference on read_disk yet */
357 static void close_write(struct r1bio
*r1_bio
)
359 /* it really is the end of this request */
360 if (test_bit(R1BIO_BehindIO
, &r1_bio
->state
)) {
361 /* free extra copy of the data pages */
362 int i
= r1_bio
->behind_page_count
;
364 safe_put_page(r1_bio
->behind_bvecs
[i
].bv_page
);
365 kfree(r1_bio
->behind_bvecs
);
366 r1_bio
->behind_bvecs
= NULL
;
368 /* clear the bitmap if all writes complete successfully */
369 bitmap_endwrite(r1_bio
->mddev
->bitmap
, r1_bio
->sector
,
371 !test_bit(R1BIO_Degraded
, &r1_bio
->state
),
372 test_bit(R1BIO_BehindIO
, &r1_bio
->state
));
373 md_write_end(r1_bio
->mddev
);
376 static void r1_bio_write_done(struct r1bio
*r1_bio
)
378 if (!atomic_dec_and_test(&r1_bio
->remaining
))
381 if (test_bit(R1BIO_WriteError
, &r1_bio
->state
))
382 reschedule_retry(r1_bio
);
385 if (test_bit(R1BIO_MadeGood
, &r1_bio
->state
))
386 reschedule_retry(r1_bio
);
388 raid_end_bio_io(r1_bio
);
392 static void raid1_end_write_request(struct bio
*bio
, int error
)
394 int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
395 struct r1bio
*r1_bio
= bio
->bi_private
;
396 int mirror
, behind
= test_bit(R1BIO_BehindIO
, &r1_bio
->state
);
397 struct r1conf
*conf
= r1_bio
->mddev
->private;
398 struct bio
*to_put
= NULL
;
400 mirror
= find_bio_disk(r1_bio
, bio
);
403 * 'one mirror IO has finished' event handler:
406 set_bit(WriteErrorSeen
,
407 &conf
->mirrors
[mirror
].rdev
->flags
);
408 if (!test_and_set_bit(WantReplacement
,
409 &conf
->mirrors
[mirror
].rdev
->flags
))
410 set_bit(MD_RECOVERY_NEEDED
, &
411 conf
->mddev
->recovery
);
413 set_bit(R1BIO_WriteError
, &r1_bio
->state
);
416 * Set R1BIO_Uptodate in our master bio, so that we
417 * will return a good error code for to the higher
418 * levels even if IO on some other mirrored buffer
421 * The 'master' represents the composite IO operation
422 * to user-side. So if something waits for IO, then it
423 * will wait for the 'master' bio.
428 r1_bio
->bios
[mirror
] = NULL
;
431 * Do not set R1BIO_Uptodate if the current device is
432 * rebuilding or Faulty. This is because we cannot use
433 * such device for properly reading the data back (we could
434 * potentially use it, if the current write would have felt
435 * before rdev->recovery_offset, but for simplicity we don't
438 if (test_bit(In_sync
, &conf
->mirrors
[mirror
].rdev
->flags
) &&
439 !test_bit(Faulty
, &conf
->mirrors
[mirror
].rdev
->flags
))
440 set_bit(R1BIO_Uptodate
, &r1_bio
->state
);
442 /* Maybe we can clear some bad blocks. */
443 if (is_badblock(conf
->mirrors
[mirror
].rdev
,
444 r1_bio
->sector
, r1_bio
->sectors
,
445 &first_bad
, &bad_sectors
)) {
446 r1_bio
->bios
[mirror
] = IO_MADE_GOOD
;
447 set_bit(R1BIO_MadeGood
, &r1_bio
->state
);
452 if (test_bit(WriteMostly
, &conf
->mirrors
[mirror
].rdev
->flags
))
453 atomic_dec(&r1_bio
->behind_remaining
);
456 * In behind mode, we ACK the master bio once the I/O
457 * has safely reached all non-writemostly
458 * disks. Setting the Returned bit ensures that this
459 * gets done only once -- we don't ever want to return
460 * -EIO here, instead we'll wait
462 if (atomic_read(&r1_bio
->behind_remaining
) >= (atomic_read(&r1_bio
->remaining
)-1) &&
463 test_bit(R1BIO_Uptodate
, &r1_bio
->state
)) {
464 /* Maybe we can return now */
465 if (!test_and_set_bit(R1BIO_Returned
, &r1_bio
->state
)) {
466 struct bio
*mbio
= r1_bio
->master_bio
;
467 pr_debug("raid1: behind end write sectors"
469 (unsigned long long) mbio
->bi_sector
,
470 (unsigned long long) mbio
->bi_sector
+
471 bio_sectors(mbio
) - 1);
472 call_bio_endio(r1_bio
);
476 if (r1_bio
->bios
[mirror
] == NULL
)
477 rdev_dec_pending(conf
->mirrors
[mirror
].rdev
,
481 * Let's see if all mirrored write operations have finished
484 r1_bio_write_done(r1_bio
);
492 * This routine returns the disk from which the requested read should
493 * be done. There is a per-array 'next expected sequential IO' sector
494 * number - if this matches on the next IO then we use the last disk.
495 * There is also a per-disk 'last know head position' sector that is
496 * maintained from IRQ contexts, both the normal and the resync IO
497 * completion handlers update this position correctly. If there is no
498 * perfect sequential match then we pick the disk whose head is closest.
500 * If there are 2 mirrors in the same 2 devices, performance degrades
501 * because position is mirror, not device based.
503 * The rdev for the device selected will have nr_pending incremented.
505 static int read_balance(struct r1conf
*conf
, struct r1bio
*r1_bio
, int *max_sectors
)
507 const sector_t this_sector
= r1_bio
->sector
;
509 int best_good_sectors
;
510 int best_disk
, best_dist_disk
, best_pending_disk
;
514 unsigned int min_pending
;
515 struct md_rdev
*rdev
;
517 int choose_next_idle
;
521 * Check if we can balance. We can balance on the whole
522 * device if no resync is going on, or below the resync window.
523 * We take the first readable disk when above the resync window.
526 sectors
= r1_bio
->sectors
;
529 best_dist
= MaxSector
;
530 best_pending_disk
= -1;
531 min_pending
= UINT_MAX
;
532 best_good_sectors
= 0;
534 choose_next_idle
= 0;
536 if (conf
->mddev
->recovery_cp
< MaxSector
&&
537 (this_sector
+ sectors
>= conf
->next_resync
))
542 for (disk
= 0 ; disk
< conf
->raid_disks
* 2 ; disk
++) {
546 unsigned int pending
;
549 rdev
= rcu_dereference(conf
->mirrors
[disk
].rdev
);
550 if (r1_bio
->bios
[disk
] == IO_BLOCKED
552 || test_bit(Unmerged
, &rdev
->flags
)
553 || test_bit(Faulty
, &rdev
->flags
))
555 if (!test_bit(In_sync
, &rdev
->flags
) &&
556 rdev
->recovery_offset
< this_sector
+ sectors
)
558 if (test_bit(WriteMostly
, &rdev
->flags
)) {
559 /* Don't balance among write-mostly, just
560 * use the first as a last resort */
562 if (is_badblock(rdev
, this_sector
, sectors
,
563 &first_bad
, &bad_sectors
)) {
564 if (first_bad
< this_sector
)
565 /* Cannot use this */
567 best_good_sectors
= first_bad
- this_sector
;
569 best_good_sectors
= sectors
;
574 /* This is a reasonable device to use. It might
577 if (is_badblock(rdev
, this_sector
, sectors
,
578 &first_bad
, &bad_sectors
)) {
579 if (best_dist
< MaxSector
)
580 /* already have a better device */
582 if (first_bad
<= this_sector
) {
583 /* cannot read here. If this is the 'primary'
584 * device, then we must not read beyond
585 * bad_sectors from another device..
587 bad_sectors
-= (this_sector
- first_bad
);
588 if (choose_first
&& sectors
> bad_sectors
)
589 sectors
= bad_sectors
;
590 if (best_good_sectors
> sectors
)
591 best_good_sectors
= sectors
;
594 sector_t good_sectors
= first_bad
- this_sector
;
595 if (good_sectors
> best_good_sectors
) {
596 best_good_sectors
= good_sectors
;
604 best_good_sectors
= sectors
;
606 nonrot
= blk_queue_nonrot(bdev_get_queue(rdev
->bdev
));
607 has_nonrot_disk
|= nonrot
;
608 pending
= atomic_read(&rdev
->nr_pending
);
609 dist
= abs(this_sector
- conf
->mirrors
[disk
].head_position
);
614 /* Don't change to another disk for sequential reads */
615 if (conf
->mirrors
[disk
].next_seq_sect
== this_sector
617 int opt_iosize
= bdev_io_opt(rdev
->bdev
) >> 9;
618 struct raid1_info
*mirror
= &conf
->mirrors
[disk
];
622 * If buffered sequential IO size exceeds optimal
623 * iosize, check if there is idle disk. If yes, choose
624 * the idle disk. read_balance could already choose an
625 * idle disk before noticing it's a sequential IO in
626 * this disk. This doesn't matter because this disk
627 * will idle, next time it will be utilized after the
628 * first disk has IO size exceeds optimal iosize. In
629 * this way, iosize of the first disk will be optimal
630 * iosize at least. iosize of the second disk might be
631 * small, but not a big deal since when the second disk
632 * starts IO, the first disk is likely still busy.
634 if (nonrot
&& opt_iosize
> 0 &&
635 mirror
->seq_start
!= MaxSector
&&
636 mirror
->next_seq_sect
> opt_iosize
&&
637 mirror
->next_seq_sect
- opt_iosize
>=
639 choose_next_idle
= 1;
644 /* If device is idle, use it */
650 if (choose_next_idle
)
653 if (min_pending
> pending
) {
654 min_pending
= pending
;
655 best_pending_disk
= disk
;
658 if (dist
< best_dist
) {
660 best_dist_disk
= disk
;
665 * If all disks are rotational, choose the closest disk. If any disk is
666 * non-rotational, choose the disk with less pending request even the
667 * disk is rotational, which might/might not be optimal for raids with
668 * mixed ratation/non-rotational disks depending on workload.
670 if (best_disk
== -1) {
672 best_disk
= best_pending_disk
;
674 best_disk
= best_dist_disk
;
677 if (best_disk
>= 0) {
678 rdev
= rcu_dereference(conf
->mirrors
[best_disk
].rdev
);
681 atomic_inc(&rdev
->nr_pending
);
682 if (test_bit(Faulty
, &rdev
->flags
)) {
683 /* cannot risk returning a device that failed
684 * before we inc'ed nr_pending
686 rdev_dec_pending(rdev
, conf
->mddev
);
689 sectors
= best_good_sectors
;
691 if (conf
->mirrors
[best_disk
].next_seq_sect
!= this_sector
)
692 conf
->mirrors
[best_disk
].seq_start
= this_sector
;
694 conf
->mirrors
[best_disk
].next_seq_sect
= this_sector
+ sectors
;
697 *max_sectors
= sectors
;
702 static int raid1_mergeable_bvec(struct request_queue
*q
,
703 struct bvec_merge_data
*bvm
,
704 struct bio_vec
*biovec
)
706 struct mddev
*mddev
= q
->queuedata
;
707 struct r1conf
*conf
= mddev
->private;
708 sector_t sector
= bvm
->bi_sector
+ get_start_sect(bvm
->bi_bdev
);
709 int max
= biovec
->bv_len
;
711 if (mddev
->merge_check_needed
) {
714 for (disk
= 0; disk
< conf
->raid_disks
* 2; disk
++) {
715 struct md_rdev
*rdev
= rcu_dereference(
716 conf
->mirrors
[disk
].rdev
);
717 if (rdev
&& !test_bit(Faulty
, &rdev
->flags
)) {
718 struct request_queue
*q
=
719 bdev_get_queue(rdev
->bdev
);
720 if (q
->merge_bvec_fn
) {
721 bvm
->bi_sector
= sector
+
723 bvm
->bi_bdev
= rdev
->bdev
;
724 max
= min(max
, q
->merge_bvec_fn(
735 int md_raid1_congested(struct mddev
*mddev
, int bits
)
737 struct r1conf
*conf
= mddev
->private;
740 if ((bits
& (1 << BDI_async_congested
)) &&
741 conf
->pending_count
>= max_queued_requests
)
745 for (i
= 0; i
< conf
->raid_disks
* 2; i
++) {
746 struct md_rdev
*rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
747 if (rdev
&& !test_bit(Faulty
, &rdev
->flags
)) {
748 struct request_queue
*q
= bdev_get_queue(rdev
->bdev
);
752 /* Note the '|| 1' - when read_balance prefers
753 * non-congested targets, it can be removed
755 if ((bits
& (1<<BDI_async_congested
)) || 1)
756 ret
|= bdi_congested(&q
->backing_dev_info
, bits
);
758 ret
&= bdi_congested(&q
->backing_dev_info
, bits
);
764 EXPORT_SYMBOL_GPL(md_raid1_congested
);
766 static int raid1_congested(void *data
, int bits
)
768 struct mddev
*mddev
= data
;
770 return mddev_congested(mddev
, bits
) ||
771 md_raid1_congested(mddev
, bits
);
774 static void flush_pending_writes(struct r1conf
*conf
)
776 /* Any writes that have been queued but are awaiting
777 * bitmap updates get flushed here.
779 spin_lock_irq(&conf
->device_lock
);
781 if (conf
->pending_bio_list
.head
) {
783 bio
= bio_list_get(&conf
->pending_bio_list
);
784 conf
->pending_count
= 0;
785 spin_unlock_irq(&conf
->device_lock
);
786 /* flush any pending bitmap writes to
787 * disk before proceeding w/ I/O */
788 bitmap_unplug(conf
->mddev
->bitmap
);
789 wake_up(&conf
->wait_barrier
);
791 while (bio
) { /* submit pending writes */
792 struct bio
*next
= bio
->bi_next
;
794 if (unlikely((bio
->bi_rw
& REQ_DISCARD
) &&
795 !blk_queue_discard(bdev_get_queue(bio
->bi_bdev
))))
799 generic_make_request(bio
);
803 spin_unlock_irq(&conf
->device_lock
);
807 * Sometimes we need to suspend IO while we do something else,
808 * either some resync/recovery, or reconfigure the array.
809 * To do this we raise a 'barrier'.
810 * The 'barrier' is a counter that can be raised multiple times
811 * to count how many activities are happening which preclude
813 * We can only raise the barrier if there is no pending IO.
814 * i.e. if nr_pending == 0.
815 * We choose only to raise the barrier if no-one is waiting for the
816 * barrier to go down. This means that as soon as an IO request
817 * is ready, no other operations which require a barrier will start
818 * until the IO request has had a chance.
820 * So: regular IO calls 'wait_barrier'. When that returns there
821 * is no backgroup IO happening, It must arrange to call
822 * allow_barrier when it has finished its IO.
823 * backgroup IO calls must call raise_barrier. Once that returns
824 * there is no normal IO happeing. It must arrange to call
825 * lower_barrier when the particular background IO completes.
827 static void raise_barrier(struct r1conf
*conf
)
829 spin_lock_irq(&conf
->resync_lock
);
831 /* Wait until no block IO is waiting */
832 wait_event_lock_irq(conf
->wait_barrier
, !conf
->nr_waiting
,
835 /* block any new IO from starting */
838 /* For these conditions we must wait:
839 * A: while the array is in frozen state
840 * B: while barrier >= RESYNC_DEPTH, meaning resync reach
841 * the max count which allowed.
842 * C: next_resync + RESYNC_SECTORS > start_next_window, meaning
843 * next resync will reach to the window which normal bios are
846 wait_event_lock_irq(conf
->wait_barrier
,
847 !conf
->array_frozen
&&
848 conf
->barrier
< RESYNC_DEPTH
&&
849 (conf
->start_next_window
>=
850 conf
->next_resync
+ RESYNC_SECTORS
),
853 spin_unlock_irq(&conf
->resync_lock
);
856 static void lower_barrier(struct r1conf
*conf
)
859 BUG_ON(conf
->barrier
<= 0);
860 spin_lock_irqsave(&conf
->resync_lock
, flags
);
862 spin_unlock_irqrestore(&conf
->resync_lock
, flags
);
863 wake_up(&conf
->wait_barrier
);
866 static bool need_to_wait_for_sync(struct r1conf
*conf
, struct bio
*bio
)
870 if (conf
->array_frozen
|| !bio
)
872 else if (conf
->barrier
&& bio_data_dir(bio
) == WRITE
) {
873 if (conf
->next_resync
< RESYNC_WINDOW_SECTORS
)
875 else if ((conf
->next_resync
- RESYNC_WINDOW_SECTORS
876 >= bio_end_sector(bio
)) ||
877 (conf
->next_resync
+ NEXT_NORMALIO_DISTANCE
887 static sector_t
wait_barrier(struct r1conf
*conf
, struct bio
*bio
)
891 spin_lock_irq(&conf
->resync_lock
);
892 if (need_to_wait_for_sync(conf
, bio
)) {
894 /* Wait for the barrier to drop.
895 * However if there are already pending
896 * requests (preventing the barrier from
897 * rising completely), and the
898 * pre-process bio queue isn't empty,
899 * then don't wait, as we need to empty
900 * that queue to get the nr_pending
903 wait_event_lock_irq(conf
->wait_barrier
,
904 !conf
->array_frozen
&&
906 ((conf
->start_next_window
<
907 conf
->next_resync
+ RESYNC_SECTORS
) &&
909 !bio_list_empty(current
->bio_list
))),
914 if (bio
&& bio_data_dir(bio
) == WRITE
) {
915 if (conf
->next_resync
+ NEXT_NORMALIO_DISTANCE
917 if (conf
->start_next_window
== MaxSector
)
918 conf
->start_next_window
=
920 NEXT_NORMALIO_DISTANCE
;
922 if ((conf
->start_next_window
+ NEXT_NORMALIO_DISTANCE
)
924 conf
->next_window_requests
++;
926 conf
->current_window_requests
++;
927 sector
= conf
->start_next_window
;
932 spin_unlock_irq(&conf
->resync_lock
);
936 static void allow_barrier(struct r1conf
*conf
, sector_t start_next_window
,
941 spin_lock_irqsave(&conf
->resync_lock
, flags
);
943 if (start_next_window
) {
944 if (start_next_window
== conf
->start_next_window
) {
945 if (conf
->start_next_window
+ NEXT_NORMALIO_DISTANCE
947 conf
->next_window_requests
--;
949 conf
->current_window_requests
--;
951 conf
->current_window_requests
--;
953 if (!conf
->current_window_requests
) {
954 if (conf
->next_window_requests
) {
955 conf
->current_window_requests
=
956 conf
->next_window_requests
;
957 conf
->next_window_requests
= 0;
958 conf
->start_next_window
+=
959 NEXT_NORMALIO_DISTANCE
;
961 conf
->start_next_window
= MaxSector
;
964 spin_unlock_irqrestore(&conf
->resync_lock
, flags
);
965 wake_up(&conf
->wait_barrier
);
968 static void freeze_array(struct r1conf
*conf
, int extra
)
970 /* stop syncio and normal IO and wait for everything to
972 * We wait until nr_pending match nr_queued+extra
973 * This is called in the context of one normal IO request
974 * that has failed. Thus any sync request that might be pending
975 * will be blocked by nr_pending, and we need to wait for
976 * pending IO requests to complete or be queued for re-try.
977 * Thus the number queued (nr_queued) plus this request (extra)
978 * must match the number of pending IOs (nr_pending) before
981 spin_lock_irq(&conf
->resync_lock
);
982 conf
->array_frozen
= 1;
983 wait_event_lock_irq_cmd(conf
->wait_barrier
,
984 conf
->nr_pending
== conf
->nr_queued
+extra
,
986 flush_pending_writes(conf
));
987 spin_unlock_irq(&conf
->resync_lock
);
989 static void unfreeze_array(struct r1conf
*conf
)
991 /* reverse the effect of the freeze */
992 spin_lock_irq(&conf
->resync_lock
);
993 conf
->array_frozen
= 0;
994 wake_up(&conf
->wait_barrier
);
995 spin_unlock_irq(&conf
->resync_lock
);
999 /* duplicate the data pages for behind I/O
1001 static void alloc_behind_pages(struct bio
*bio
, struct r1bio
*r1_bio
)
1004 struct bio_vec
*bvec
;
1005 struct bio_vec
*bvecs
= kzalloc(bio
->bi_vcnt
* sizeof(struct bio_vec
),
1007 if (unlikely(!bvecs
))
1010 bio_for_each_segment_all(bvec
, bio
, i
) {
1012 bvecs
[i
].bv_page
= alloc_page(GFP_NOIO
);
1013 if (unlikely(!bvecs
[i
].bv_page
))
1015 memcpy(kmap(bvecs
[i
].bv_page
) + bvec
->bv_offset
,
1016 kmap(bvec
->bv_page
) + bvec
->bv_offset
, bvec
->bv_len
);
1017 kunmap(bvecs
[i
].bv_page
);
1018 kunmap(bvec
->bv_page
);
1020 r1_bio
->behind_bvecs
= bvecs
;
1021 r1_bio
->behind_page_count
= bio
->bi_vcnt
;
1022 set_bit(R1BIO_BehindIO
, &r1_bio
->state
);
1026 for (i
= 0; i
< bio
->bi_vcnt
; i
++)
1027 if (bvecs
[i
].bv_page
)
1028 put_page(bvecs
[i
].bv_page
);
1030 pr_debug("%dB behind alloc failed, doing sync I/O\n", bio
->bi_size
);
1033 struct raid1_plug_cb
{
1034 struct blk_plug_cb cb
;
1035 struct bio_list pending
;
1039 static void raid1_unplug(struct blk_plug_cb
*cb
, bool from_schedule
)
1041 struct raid1_plug_cb
*plug
= container_of(cb
, struct raid1_plug_cb
,
1043 struct mddev
*mddev
= plug
->cb
.data
;
1044 struct r1conf
*conf
= mddev
->private;
1047 if (from_schedule
|| current
->bio_list
) {
1048 spin_lock_irq(&conf
->device_lock
);
1049 bio_list_merge(&conf
->pending_bio_list
, &plug
->pending
);
1050 conf
->pending_count
+= plug
->pending_cnt
;
1051 spin_unlock_irq(&conf
->device_lock
);
1052 wake_up(&conf
->wait_barrier
);
1053 md_wakeup_thread(mddev
->thread
);
1058 /* we aren't scheduling, so we can do the write-out directly. */
1059 bio
= bio_list_get(&plug
->pending
);
1060 bitmap_unplug(mddev
->bitmap
);
1061 wake_up(&conf
->wait_barrier
);
1063 while (bio
) { /* submit pending writes */
1064 struct bio
*next
= bio
->bi_next
;
1065 bio
->bi_next
= NULL
;
1066 if (unlikely((bio
->bi_rw
& REQ_DISCARD
) &&
1067 !blk_queue_discard(bdev_get_queue(bio
->bi_bdev
))))
1068 /* Just ignore it */
1071 generic_make_request(bio
);
1077 static void make_request(struct mddev
*mddev
, struct bio
* bio
)
1079 struct r1conf
*conf
= mddev
->private;
1080 struct raid1_info
*mirror
;
1081 struct r1bio
*r1_bio
;
1082 struct bio
*read_bio
;
1084 struct bitmap
*bitmap
;
1085 unsigned long flags
;
1086 const int rw
= bio_data_dir(bio
);
1087 const unsigned long do_sync
= (bio
->bi_rw
& REQ_SYNC
);
1088 const unsigned long do_flush_fua
= (bio
->bi_rw
& (REQ_FLUSH
| REQ_FUA
));
1089 const unsigned long do_discard
= (bio
->bi_rw
1090 & (REQ_DISCARD
| REQ_SECURE
));
1091 const unsigned long do_same
= (bio
->bi_rw
& REQ_WRITE_SAME
);
1092 struct md_rdev
*blocked_rdev
;
1093 struct blk_plug_cb
*cb
;
1094 struct raid1_plug_cb
*plug
= NULL
;
1096 int sectors_handled
;
1098 sector_t start_next_window
;
1101 * Register the new request and wait if the reconstruction
1102 * thread has put up a bar for new requests.
1103 * Continue immediately if no resync is active currently.
1106 md_write_start(mddev
, bio
); /* wait on superblock update early */
1108 if (bio_data_dir(bio
) == WRITE
&&
1109 bio_end_sector(bio
) > mddev
->suspend_lo
&&
1110 bio
->bi_sector
< mddev
->suspend_hi
) {
1111 /* As the suspend_* range is controlled by
1112 * userspace, we want an interruptible
1117 flush_signals(current
);
1118 prepare_to_wait(&conf
->wait_barrier
,
1119 &w
, TASK_INTERRUPTIBLE
);
1120 if (bio_end_sector(bio
) <= mddev
->suspend_lo
||
1121 bio
->bi_sector
>= mddev
->suspend_hi
)
1125 finish_wait(&conf
->wait_barrier
, &w
);
1128 start_next_window
= wait_barrier(conf
, bio
);
1130 bitmap
= mddev
->bitmap
;
1133 * make_request() can abort the operation when READA is being
1134 * used and no empty request is available.
1137 r1_bio
= mempool_alloc(conf
->r1bio_pool
, GFP_NOIO
);
1139 r1_bio
->master_bio
= bio
;
1140 r1_bio
->sectors
= bio_sectors(bio
);
1142 r1_bio
->mddev
= mddev
;
1143 r1_bio
->sector
= bio
->bi_sector
;
1145 /* We might need to issue multiple reads to different
1146 * devices if there are bad blocks around, so we keep
1147 * track of the number of reads in bio->bi_phys_segments.
1148 * If this is 0, there is only one r1_bio and no locking
1149 * will be needed when requests complete. If it is
1150 * non-zero, then it is the number of not-completed requests.
1152 bio
->bi_phys_segments
= 0;
1153 clear_bit(BIO_SEG_VALID
, &bio
->bi_flags
);
1157 * read balancing logic:
1162 rdisk
= read_balance(conf
, r1_bio
, &max_sectors
);
1165 /* couldn't find anywhere to read from */
1166 raid_end_bio_io(r1_bio
);
1169 mirror
= conf
->mirrors
+ rdisk
;
1171 if (test_bit(WriteMostly
, &mirror
->rdev
->flags
) &&
1173 /* Reading from a write-mostly device must
1174 * take care not to over-take any writes
1177 wait_event(bitmap
->behind_wait
,
1178 atomic_read(&bitmap
->behind_writes
) == 0);
1180 r1_bio
->read_disk
= rdisk
;
1182 read_bio
= bio_clone_mddev(bio
, GFP_NOIO
, mddev
);
1183 bio_trim(read_bio
, r1_bio
->sector
- bio
->bi_sector
,
1186 r1_bio
->bios
[rdisk
] = read_bio
;
1188 read_bio
->bi_sector
= r1_bio
->sector
+ mirror
->rdev
->data_offset
;
1189 read_bio
->bi_bdev
= mirror
->rdev
->bdev
;
1190 read_bio
->bi_end_io
= raid1_end_read_request
;
1191 read_bio
->bi_rw
= READ
| do_sync
;
1192 read_bio
->bi_private
= r1_bio
;
1194 if (max_sectors
< r1_bio
->sectors
) {
1195 /* could not read all from this device, so we will
1196 * need another r1_bio.
1199 sectors_handled
= (r1_bio
->sector
+ max_sectors
1201 r1_bio
->sectors
= max_sectors
;
1202 spin_lock_irq(&conf
->device_lock
);
1203 if (bio
->bi_phys_segments
== 0)
1204 bio
->bi_phys_segments
= 2;
1206 bio
->bi_phys_segments
++;
1207 spin_unlock_irq(&conf
->device_lock
);
1208 /* Cannot call generic_make_request directly
1209 * as that will be queued in __make_request
1210 * and subsequent mempool_alloc might block waiting
1211 * for it. So hand bio over to raid1d.
1213 reschedule_retry(r1_bio
);
1215 r1_bio
= mempool_alloc(conf
->r1bio_pool
, GFP_NOIO
);
1217 r1_bio
->master_bio
= bio
;
1218 r1_bio
->sectors
= bio_sectors(bio
) - sectors_handled
;
1220 r1_bio
->mddev
= mddev
;
1221 r1_bio
->sector
= bio
->bi_sector
+ sectors_handled
;
1224 generic_make_request(read_bio
);
1231 if (conf
->pending_count
>= max_queued_requests
) {
1232 md_wakeup_thread(mddev
->thread
);
1233 wait_event(conf
->wait_barrier
,
1234 conf
->pending_count
< max_queued_requests
);
1236 /* first select target devices under rcu_lock and
1237 * inc refcount on their rdev. Record them by setting
1239 * If there are known/acknowledged bad blocks on any device on
1240 * which we have seen a write error, we want to avoid writing those
1242 * This potentially requires several writes to write around
1243 * the bad blocks. Each set of writes gets it's own r1bio
1244 * with a set of bios attached.
1247 disks
= conf
->raid_disks
* 2;
1249 r1_bio
->start_next_window
= start_next_window
;
1250 blocked_rdev
= NULL
;
1252 max_sectors
= r1_bio
->sectors
;
1253 for (i
= 0; i
< disks
; i
++) {
1254 struct md_rdev
*rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
1255 if (rdev
&& unlikely(test_bit(Blocked
, &rdev
->flags
))) {
1256 atomic_inc(&rdev
->nr_pending
);
1257 blocked_rdev
= rdev
;
1260 r1_bio
->bios
[i
] = NULL
;
1261 if (!rdev
|| test_bit(Faulty
, &rdev
->flags
)
1262 || test_bit(Unmerged
, &rdev
->flags
)) {
1263 if (i
< conf
->raid_disks
)
1264 set_bit(R1BIO_Degraded
, &r1_bio
->state
);
1268 atomic_inc(&rdev
->nr_pending
);
1269 if (test_bit(WriteErrorSeen
, &rdev
->flags
)) {
1274 is_bad
= is_badblock(rdev
, r1_bio
->sector
,
1276 &first_bad
, &bad_sectors
);
1278 /* mustn't write here until the bad block is
1280 set_bit(BlockedBadBlocks
, &rdev
->flags
);
1281 blocked_rdev
= rdev
;
1284 if (is_bad
&& first_bad
<= r1_bio
->sector
) {
1285 /* Cannot write here at all */
1286 bad_sectors
-= (r1_bio
->sector
- first_bad
);
1287 if (bad_sectors
< max_sectors
)
1288 /* mustn't write more than bad_sectors
1289 * to other devices yet
1291 max_sectors
= bad_sectors
;
1292 rdev_dec_pending(rdev
, mddev
);
1293 /* We don't set R1BIO_Degraded as that
1294 * only applies if the disk is
1295 * missing, so it might be re-added,
1296 * and we want to know to recover this
1298 * In this case the device is here,
1299 * and the fact that this chunk is not
1300 * in-sync is recorded in the bad
1306 int good_sectors
= first_bad
- r1_bio
->sector
;
1307 if (good_sectors
< max_sectors
)
1308 max_sectors
= good_sectors
;
1311 r1_bio
->bios
[i
] = bio
;
1315 if (unlikely(blocked_rdev
)) {
1316 /* Wait for this device to become unblocked */
1318 sector_t old
= start_next_window
;
1320 for (j
= 0; j
< i
; j
++)
1321 if (r1_bio
->bios
[j
])
1322 rdev_dec_pending(conf
->mirrors
[j
].rdev
, mddev
);
1324 allow_barrier(conf
, start_next_window
, bio
->bi_sector
);
1325 md_wait_for_blocked_rdev(blocked_rdev
, mddev
);
1326 start_next_window
= wait_barrier(conf
, bio
);
1328 * We must make sure the multi r1bios of bio have
1329 * the same value of bi_phys_segments
1331 if (bio
->bi_phys_segments
&& old
&&
1332 old
!= start_next_window
)
1333 /* Wait for the former r1bio(s) to complete */
1334 wait_event(conf
->wait_barrier
,
1335 bio
->bi_phys_segments
== 1);
1339 if (max_sectors
< r1_bio
->sectors
) {
1340 /* We are splitting this write into multiple parts, so
1341 * we need to prepare for allocating another r1_bio.
1343 r1_bio
->sectors
= max_sectors
;
1344 spin_lock_irq(&conf
->device_lock
);
1345 if (bio
->bi_phys_segments
== 0)
1346 bio
->bi_phys_segments
= 2;
1348 bio
->bi_phys_segments
++;
1349 spin_unlock_irq(&conf
->device_lock
);
1351 sectors_handled
= r1_bio
->sector
+ max_sectors
- bio
->bi_sector
;
1353 atomic_set(&r1_bio
->remaining
, 1);
1354 atomic_set(&r1_bio
->behind_remaining
, 0);
1357 for (i
= 0; i
< disks
; i
++) {
1359 if (!r1_bio
->bios
[i
])
1362 mbio
= bio_clone_mddev(bio
, GFP_NOIO
, mddev
);
1363 bio_trim(mbio
, r1_bio
->sector
- bio
->bi_sector
, max_sectors
);
1367 * Not if there are too many, or cannot
1368 * allocate memory, or a reader on WriteMostly
1369 * is waiting for behind writes to flush */
1371 (atomic_read(&bitmap
->behind_writes
)
1372 < mddev
->bitmap_info
.max_write_behind
) &&
1373 !waitqueue_active(&bitmap
->behind_wait
))
1374 alloc_behind_pages(mbio
, r1_bio
);
1376 bitmap_startwrite(bitmap
, r1_bio
->sector
,
1378 test_bit(R1BIO_BehindIO
,
1382 if (r1_bio
->behind_bvecs
) {
1383 struct bio_vec
*bvec
;
1387 * We trimmed the bio, so _all is legit
1389 bio_for_each_segment_all(bvec
, mbio
, j
)
1390 bvec
->bv_page
= r1_bio
->behind_bvecs
[j
].bv_page
;
1391 if (test_bit(WriteMostly
, &conf
->mirrors
[i
].rdev
->flags
))
1392 atomic_inc(&r1_bio
->behind_remaining
);
1395 r1_bio
->bios
[i
] = mbio
;
1397 mbio
->bi_sector
= (r1_bio
->sector
+
1398 conf
->mirrors
[i
].rdev
->data_offset
);
1399 mbio
->bi_bdev
= conf
->mirrors
[i
].rdev
->bdev
;
1400 mbio
->bi_end_io
= raid1_end_write_request
;
1402 WRITE
| do_flush_fua
| do_sync
| do_discard
| do_same
;
1403 mbio
->bi_private
= r1_bio
;
1405 atomic_inc(&r1_bio
->remaining
);
1407 cb
= blk_check_plugged(raid1_unplug
, mddev
, sizeof(*plug
));
1409 plug
= container_of(cb
, struct raid1_plug_cb
, cb
);
1412 spin_lock_irqsave(&conf
->device_lock
, flags
);
1414 bio_list_add(&plug
->pending
, mbio
);
1415 plug
->pending_cnt
++;
1417 bio_list_add(&conf
->pending_bio_list
, mbio
);
1418 conf
->pending_count
++;
1420 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
1422 md_wakeup_thread(mddev
->thread
);
1424 /* Mustn't call r1_bio_write_done before this next test,
1425 * as it could result in the bio being freed.
1427 if (sectors_handled
< bio_sectors(bio
)) {
1428 r1_bio_write_done(r1_bio
);
1429 /* We need another r1_bio. It has already been counted
1430 * in bio->bi_phys_segments
1432 r1_bio
= mempool_alloc(conf
->r1bio_pool
, GFP_NOIO
);
1433 r1_bio
->master_bio
= bio
;
1434 r1_bio
->sectors
= bio_sectors(bio
) - sectors_handled
;
1436 r1_bio
->mddev
= mddev
;
1437 r1_bio
->sector
= bio
->bi_sector
+ sectors_handled
;
1441 r1_bio_write_done(r1_bio
);
1443 /* In case raid1d snuck in to freeze_array */
1444 wake_up(&conf
->wait_barrier
);
1447 static void status(struct seq_file
*seq
, struct mddev
*mddev
)
1449 struct r1conf
*conf
= mddev
->private;
1452 seq_printf(seq
, " [%d/%d] [", conf
->raid_disks
,
1453 conf
->raid_disks
- mddev
->degraded
);
1455 for (i
= 0; i
< conf
->raid_disks
; i
++) {
1456 struct md_rdev
*rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
1457 seq_printf(seq
, "%s",
1458 rdev
&& test_bit(In_sync
, &rdev
->flags
) ? "U" : "_");
1461 seq_printf(seq
, "]");
1465 static void error(struct mddev
*mddev
, struct md_rdev
*rdev
)
1467 char b
[BDEVNAME_SIZE
];
1468 struct r1conf
*conf
= mddev
->private;
1471 * If it is not operational, then we have already marked it as dead
1472 * else if it is the last working disks, ignore the error, let the
1473 * next level up know.
1474 * else mark the drive as failed
1476 if (test_bit(In_sync
, &rdev
->flags
)
1477 && (conf
->raid_disks
- mddev
->degraded
) == 1) {
1479 * Don't fail the drive, act as though we were just a
1480 * normal single drive.
1481 * However don't try a recovery from this drive as
1482 * it is very likely to fail.
1484 conf
->recovery_disabled
= mddev
->recovery_disabled
;
1487 set_bit(Blocked
, &rdev
->flags
);
1488 if (test_and_clear_bit(In_sync
, &rdev
->flags
)) {
1489 unsigned long flags
;
1490 spin_lock_irqsave(&conf
->device_lock
, flags
);
1492 set_bit(Faulty
, &rdev
->flags
);
1493 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
1495 * if recovery is running, make sure it aborts.
1497 set_bit(MD_RECOVERY_INTR
, &mddev
->recovery
);
1499 set_bit(Faulty
, &rdev
->flags
);
1500 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
1502 "md/raid1:%s: Disk failure on %s, disabling device.\n"
1503 "md/raid1:%s: Operation continuing on %d devices.\n",
1504 mdname(mddev
), bdevname(rdev
->bdev
, b
),
1505 mdname(mddev
), conf
->raid_disks
- mddev
->degraded
);
1508 static void print_conf(struct r1conf
*conf
)
1512 printk(KERN_DEBUG
"RAID1 conf printout:\n");
1514 printk(KERN_DEBUG
"(!conf)\n");
1517 printk(KERN_DEBUG
" --- wd:%d rd:%d\n", conf
->raid_disks
- conf
->mddev
->degraded
,
1521 for (i
= 0; i
< conf
->raid_disks
; i
++) {
1522 char b
[BDEVNAME_SIZE
];
1523 struct md_rdev
*rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
1525 printk(KERN_DEBUG
" disk %d, wo:%d, o:%d, dev:%s\n",
1526 i
, !test_bit(In_sync
, &rdev
->flags
),
1527 !test_bit(Faulty
, &rdev
->flags
),
1528 bdevname(rdev
->bdev
,b
));
1533 static void close_sync(struct r1conf
*conf
)
1535 wait_barrier(conf
, NULL
);
1536 allow_barrier(conf
, 0, 0);
1538 mempool_destroy(conf
->r1buf_pool
);
1539 conf
->r1buf_pool
= NULL
;
1541 conf
->next_resync
= 0;
1542 conf
->start_next_window
= MaxSector
;
1545 static int raid1_spare_active(struct mddev
*mddev
)
1548 struct r1conf
*conf
= mddev
->private;
1550 unsigned long flags
;
1553 * Find all failed disks within the RAID1 configuration
1554 * and mark them readable.
1555 * Called under mddev lock, so rcu protection not needed.
1557 for (i
= 0; i
< conf
->raid_disks
; i
++) {
1558 struct md_rdev
*rdev
= conf
->mirrors
[i
].rdev
;
1559 struct md_rdev
*repl
= conf
->mirrors
[conf
->raid_disks
+ i
].rdev
;
1561 && repl
->recovery_offset
== MaxSector
1562 && !test_bit(Faulty
, &repl
->flags
)
1563 && !test_and_set_bit(In_sync
, &repl
->flags
)) {
1564 /* replacement has just become active */
1566 !test_and_clear_bit(In_sync
, &rdev
->flags
))
1569 /* Replaced device not technically
1570 * faulty, but we need to be sure
1571 * it gets removed and never re-added
1573 set_bit(Faulty
, &rdev
->flags
);
1574 sysfs_notify_dirent_safe(
1579 && rdev
->recovery_offset
== MaxSector
1580 && !test_bit(Faulty
, &rdev
->flags
)
1581 && !test_and_set_bit(In_sync
, &rdev
->flags
)) {
1583 sysfs_notify_dirent_safe(rdev
->sysfs_state
);
1586 spin_lock_irqsave(&conf
->device_lock
, flags
);
1587 mddev
->degraded
-= count
;
1588 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
1595 static int raid1_add_disk(struct mddev
*mddev
, struct md_rdev
*rdev
)
1597 struct r1conf
*conf
= mddev
->private;
1600 struct raid1_info
*p
;
1602 int last
= conf
->raid_disks
- 1;
1603 struct request_queue
*q
= bdev_get_queue(rdev
->bdev
);
1605 if (mddev
->recovery_disabled
== conf
->recovery_disabled
)
1608 if (rdev
->raid_disk
>= 0)
1609 first
= last
= rdev
->raid_disk
;
1611 if (q
->merge_bvec_fn
) {
1612 set_bit(Unmerged
, &rdev
->flags
);
1613 mddev
->merge_check_needed
= 1;
1616 for (mirror
= first
; mirror
<= last
; mirror
++) {
1617 p
= conf
->mirrors
+mirror
;
1621 disk_stack_limits(mddev
->gendisk
, rdev
->bdev
,
1622 rdev
->data_offset
<< 9);
1624 p
->head_position
= 0;
1625 rdev
->raid_disk
= mirror
;
1627 /* As all devices are equivalent, we don't need a full recovery
1628 * if this was recently any drive of the array
1630 if (rdev
->saved_raid_disk
< 0)
1632 rcu_assign_pointer(p
->rdev
, rdev
);
1635 if (test_bit(WantReplacement
, &p
->rdev
->flags
) &&
1636 p
[conf
->raid_disks
].rdev
== NULL
) {
1637 /* Add this device as a replacement */
1638 clear_bit(In_sync
, &rdev
->flags
);
1639 set_bit(Replacement
, &rdev
->flags
);
1640 rdev
->raid_disk
= mirror
;
1643 rcu_assign_pointer(p
[conf
->raid_disks
].rdev
, rdev
);
1647 if (err
== 0 && test_bit(Unmerged
, &rdev
->flags
)) {
1648 /* Some requests might not have seen this new
1649 * merge_bvec_fn. We must wait for them to complete
1650 * before merging the device fully.
1651 * First we make sure any code which has tested
1652 * our function has submitted the request, then
1653 * we wait for all outstanding requests to complete.
1655 synchronize_sched();
1656 freeze_array(conf
, 0);
1657 unfreeze_array(conf
);
1658 clear_bit(Unmerged
, &rdev
->flags
);
1660 md_integrity_add_rdev(rdev
, mddev
);
1661 if (mddev
->queue
&& blk_queue_discard(bdev_get_queue(rdev
->bdev
)))
1662 queue_flag_set_unlocked(QUEUE_FLAG_DISCARD
, mddev
->queue
);
1667 static int raid1_remove_disk(struct mddev
*mddev
, struct md_rdev
*rdev
)
1669 struct r1conf
*conf
= mddev
->private;
1671 int number
= rdev
->raid_disk
;
1672 struct raid1_info
*p
= conf
->mirrors
+ number
;
1674 if (rdev
!= p
->rdev
)
1675 p
= conf
->mirrors
+ conf
->raid_disks
+ number
;
1678 if (rdev
== p
->rdev
) {
1679 if (test_bit(In_sync
, &rdev
->flags
) ||
1680 atomic_read(&rdev
->nr_pending
)) {
1684 /* Only remove non-faulty devices if recovery
1687 if (!test_bit(Faulty
, &rdev
->flags
) &&
1688 mddev
->recovery_disabled
!= conf
->recovery_disabled
&&
1689 mddev
->degraded
< conf
->raid_disks
) {
1695 if (atomic_read(&rdev
->nr_pending
)) {
1696 /* lost the race, try later */
1700 } else if (conf
->mirrors
[conf
->raid_disks
+ number
].rdev
) {
1701 /* We just removed a device that is being replaced.
1702 * Move down the replacement. We drain all IO before
1703 * doing this to avoid confusion.
1705 struct md_rdev
*repl
=
1706 conf
->mirrors
[conf
->raid_disks
+ number
].rdev
;
1707 freeze_array(conf
, 0);
1708 clear_bit(Replacement
, &repl
->flags
);
1710 conf
->mirrors
[conf
->raid_disks
+ number
].rdev
= NULL
;
1711 unfreeze_array(conf
);
1712 clear_bit(WantReplacement
, &rdev
->flags
);
1714 clear_bit(WantReplacement
, &rdev
->flags
);
1715 err
= md_integrity_register(mddev
);
1724 static void end_sync_read(struct bio
*bio
, int error
)
1726 struct r1bio
*r1_bio
= bio
->bi_private
;
1728 update_head_pos(r1_bio
->read_disk
, r1_bio
);
1731 * we have read a block, now it needs to be re-written,
1732 * or re-read if the read failed.
1733 * We don't do much here, just schedule handling by raid1d
1735 if (test_bit(BIO_UPTODATE
, &bio
->bi_flags
))
1736 set_bit(R1BIO_Uptodate
, &r1_bio
->state
);
1738 if (atomic_dec_and_test(&r1_bio
->remaining
))
1739 reschedule_retry(r1_bio
);
1742 static void end_sync_write(struct bio
*bio
, int error
)
1744 int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
1745 struct r1bio
*r1_bio
= bio
->bi_private
;
1746 struct mddev
*mddev
= r1_bio
->mddev
;
1747 struct r1conf
*conf
= mddev
->private;
1752 mirror
= find_bio_disk(r1_bio
, bio
);
1755 sector_t sync_blocks
= 0;
1756 sector_t s
= r1_bio
->sector
;
1757 long sectors_to_go
= r1_bio
->sectors
;
1758 /* make sure these bits doesn't get cleared. */
1760 bitmap_end_sync(mddev
->bitmap
, s
,
1763 sectors_to_go
-= sync_blocks
;
1764 } while (sectors_to_go
> 0);
1765 set_bit(WriteErrorSeen
,
1766 &conf
->mirrors
[mirror
].rdev
->flags
);
1767 if (!test_and_set_bit(WantReplacement
,
1768 &conf
->mirrors
[mirror
].rdev
->flags
))
1769 set_bit(MD_RECOVERY_NEEDED
, &
1771 set_bit(R1BIO_WriteError
, &r1_bio
->state
);
1772 } else if (is_badblock(conf
->mirrors
[mirror
].rdev
,
1775 &first_bad
, &bad_sectors
) &&
1776 !is_badblock(conf
->mirrors
[r1_bio
->read_disk
].rdev
,
1779 &first_bad
, &bad_sectors
)
1781 set_bit(R1BIO_MadeGood
, &r1_bio
->state
);
1783 if (atomic_dec_and_test(&r1_bio
->remaining
)) {
1784 int s
= r1_bio
->sectors
;
1785 if (test_bit(R1BIO_MadeGood
, &r1_bio
->state
) ||
1786 test_bit(R1BIO_WriteError
, &r1_bio
->state
))
1787 reschedule_retry(r1_bio
);
1790 md_done_sync(mddev
, s
, uptodate
);
1795 static int r1_sync_page_io(struct md_rdev
*rdev
, sector_t sector
,
1796 int sectors
, struct page
*page
, int rw
)
1798 if (sync_page_io(rdev
, sector
, sectors
<< 9, page
, rw
, false))
1802 set_bit(WriteErrorSeen
, &rdev
->flags
);
1803 if (!test_and_set_bit(WantReplacement
,
1805 set_bit(MD_RECOVERY_NEEDED
, &
1806 rdev
->mddev
->recovery
);
1808 /* need to record an error - either for the block or the device */
1809 if (!rdev_set_badblocks(rdev
, sector
, sectors
, 0))
1810 md_error(rdev
->mddev
, rdev
);
1814 static int fix_sync_read_error(struct r1bio
*r1_bio
)
1816 /* Try some synchronous reads of other devices to get
1817 * good data, much like with normal read errors. Only
1818 * read into the pages we already have so we don't
1819 * need to re-issue the read request.
1820 * We don't need to freeze the array, because being in an
1821 * active sync request, there is no normal IO, and
1822 * no overlapping syncs.
1823 * We don't need to check is_badblock() again as we
1824 * made sure that anything with a bad block in range
1825 * will have bi_end_io clear.
1827 struct mddev
*mddev
= r1_bio
->mddev
;
1828 struct r1conf
*conf
= mddev
->private;
1829 struct bio
*bio
= r1_bio
->bios
[r1_bio
->read_disk
];
1830 sector_t sect
= r1_bio
->sector
;
1831 int sectors
= r1_bio
->sectors
;
1836 int d
= r1_bio
->read_disk
;
1838 struct md_rdev
*rdev
;
1841 if (s
> (PAGE_SIZE
>>9))
1844 if (r1_bio
->bios
[d
]->bi_end_io
== end_sync_read
) {
1845 /* No rcu protection needed here devices
1846 * can only be removed when no resync is
1847 * active, and resync is currently active
1849 rdev
= conf
->mirrors
[d
].rdev
;
1850 if (sync_page_io(rdev
, sect
, s
<<9,
1851 bio
->bi_io_vec
[idx
].bv_page
,
1858 if (d
== conf
->raid_disks
* 2)
1860 } while (!success
&& d
!= r1_bio
->read_disk
);
1863 char b
[BDEVNAME_SIZE
];
1865 /* Cannot read from anywhere, this block is lost.
1866 * Record a bad block on each device. If that doesn't
1867 * work just disable and interrupt the recovery.
1868 * Don't fail devices as that won't really help.
1870 printk(KERN_ALERT
"md/raid1:%s: %s: unrecoverable I/O read error"
1871 " for block %llu\n",
1873 bdevname(bio
->bi_bdev
, b
),
1874 (unsigned long long)r1_bio
->sector
);
1875 for (d
= 0; d
< conf
->raid_disks
* 2; d
++) {
1876 rdev
= conf
->mirrors
[d
].rdev
;
1877 if (!rdev
|| test_bit(Faulty
, &rdev
->flags
))
1879 if (!rdev_set_badblocks(rdev
, sect
, s
, 0))
1883 conf
->recovery_disabled
=
1884 mddev
->recovery_disabled
;
1885 set_bit(MD_RECOVERY_INTR
, &mddev
->recovery
);
1886 md_done_sync(mddev
, r1_bio
->sectors
, 0);
1898 /* write it back and re-read */
1899 while (d
!= r1_bio
->read_disk
) {
1901 d
= conf
->raid_disks
* 2;
1903 if (r1_bio
->bios
[d
]->bi_end_io
!= end_sync_read
)
1905 rdev
= conf
->mirrors
[d
].rdev
;
1906 if (r1_sync_page_io(rdev
, sect
, s
,
1907 bio
->bi_io_vec
[idx
].bv_page
,
1909 r1_bio
->bios
[d
]->bi_end_io
= NULL
;
1910 rdev_dec_pending(rdev
, mddev
);
1914 while (d
!= r1_bio
->read_disk
) {
1916 d
= conf
->raid_disks
* 2;
1918 if (r1_bio
->bios
[d
]->bi_end_io
!= end_sync_read
)
1920 rdev
= conf
->mirrors
[d
].rdev
;
1921 if (r1_sync_page_io(rdev
, sect
, s
,
1922 bio
->bi_io_vec
[idx
].bv_page
,
1924 atomic_add(s
, &rdev
->corrected_errors
);
1930 set_bit(R1BIO_Uptodate
, &r1_bio
->state
);
1931 set_bit(BIO_UPTODATE
, &bio
->bi_flags
);
1935 static int process_checks(struct r1bio
*r1_bio
)
1937 /* We have read all readable devices. If we haven't
1938 * got the block, then there is no hope left.
1939 * If we have, then we want to do a comparison
1940 * and skip the write if everything is the same.
1941 * If any blocks failed to read, then we need to
1942 * attempt an over-write
1944 struct mddev
*mddev
= r1_bio
->mddev
;
1945 struct r1conf
*conf
= mddev
->private;
1950 /* Fix variable parts of all bios */
1951 vcnt
= (r1_bio
->sectors
+ PAGE_SIZE
/ 512 - 1) >> (PAGE_SHIFT
- 9);
1952 for (i
= 0; i
< conf
->raid_disks
* 2; i
++) {
1955 struct bio
*b
= r1_bio
->bios
[i
];
1956 if (b
->bi_end_io
!= end_sync_read
)
1958 /* fixup the bio for reuse */
1961 b
->bi_size
= r1_bio
->sectors
<< 9;
1962 b
->bi_sector
= r1_bio
->sector
+
1963 conf
->mirrors
[i
].rdev
->data_offset
;
1964 b
->bi_bdev
= conf
->mirrors
[i
].rdev
->bdev
;
1965 b
->bi_end_io
= end_sync_read
;
1966 b
->bi_private
= r1_bio
;
1969 for (j
= 0; j
< vcnt
; j
++) {
1971 bi
= &b
->bi_io_vec
[j
];
1973 if (size
> PAGE_SIZE
)
1974 bi
->bv_len
= PAGE_SIZE
;
1980 for (primary
= 0; primary
< conf
->raid_disks
* 2; primary
++)
1981 if (r1_bio
->bios
[primary
]->bi_end_io
== end_sync_read
&&
1982 test_bit(BIO_UPTODATE
, &r1_bio
->bios
[primary
]->bi_flags
)) {
1983 r1_bio
->bios
[primary
]->bi_end_io
= NULL
;
1984 rdev_dec_pending(conf
->mirrors
[primary
].rdev
, mddev
);
1987 r1_bio
->read_disk
= primary
;
1988 for (i
= 0; i
< conf
->raid_disks
* 2; i
++) {
1990 struct bio
*pbio
= r1_bio
->bios
[primary
];
1991 struct bio
*sbio
= r1_bio
->bios
[i
];
1993 if (sbio
->bi_end_io
!= end_sync_read
)
1996 if (test_bit(BIO_UPTODATE
, &sbio
->bi_flags
)) {
1997 for (j
= vcnt
; j
-- ; ) {
1999 p
= pbio
->bi_io_vec
[j
].bv_page
;
2000 s
= sbio
->bi_io_vec
[j
].bv_page
;
2001 if (memcmp(page_address(p
),
2003 sbio
->bi_io_vec
[j
].bv_len
))
2009 atomic64_add(r1_bio
->sectors
, &mddev
->resync_mismatches
);
2010 if (j
< 0 || (test_bit(MD_RECOVERY_CHECK
, &mddev
->recovery
)
2011 && test_bit(BIO_UPTODATE
, &sbio
->bi_flags
))) {
2012 /* No need to write to this device. */
2013 sbio
->bi_end_io
= NULL
;
2014 rdev_dec_pending(conf
->mirrors
[i
].rdev
, mddev
);
2018 bio_copy_data(sbio
, pbio
);
2023 static void sync_request_write(struct mddev
*mddev
, struct r1bio
*r1_bio
)
2025 struct r1conf
*conf
= mddev
->private;
2027 int disks
= conf
->raid_disks
* 2;
2028 struct bio
*bio
, *wbio
;
2030 bio
= r1_bio
->bios
[r1_bio
->read_disk
];
2032 if (!test_bit(R1BIO_Uptodate
, &r1_bio
->state
))
2033 /* ouch - failed to read all of that. */
2034 if (!fix_sync_read_error(r1_bio
))
2037 if (test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
))
2038 if (process_checks(r1_bio
) < 0)
2043 atomic_set(&r1_bio
->remaining
, 1);
2044 for (i
= 0; i
< disks
; i
++) {
2045 wbio
= r1_bio
->bios
[i
];
2046 if (wbio
->bi_end_io
== NULL
||
2047 (wbio
->bi_end_io
== end_sync_read
&&
2048 (i
== r1_bio
->read_disk
||
2049 !test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
))))
2052 wbio
->bi_rw
= WRITE
;
2053 wbio
->bi_end_io
= end_sync_write
;
2054 atomic_inc(&r1_bio
->remaining
);
2055 md_sync_acct(conf
->mirrors
[i
].rdev
->bdev
, bio_sectors(wbio
));
2057 generic_make_request(wbio
);
2060 if (atomic_dec_and_test(&r1_bio
->remaining
)) {
2061 /* if we're here, all write(s) have completed, so clean up */
2062 int s
= r1_bio
->sectors
;
2063 if (test_bit(R1BIO_MadeGood
, &r1_bio
->state
) ||
2064 test_bit(R1BIO_WriteError
, &r1_bio
->state
))
2065 reschedule_retry(r1_bio
);
2068 md_done_sync(mddev
, s
, 1);
2074 * This is a kernel thread which:
2076 * 1. Retries failed read operations on working mirrors.
2077 * 2. Updates the raid superblock when problems encounter.
2078 * 3. Performs writes following reads for array synchronising.
2081 static void fix_read_error(struct r1conf
*conf
, int read_disk
,
2082 sector_t sect
, int sectors
)
2084 struct mddev
*mddev
= conf
->mddev
;
2090 struct md_rdev
*rdev
;
2092 if (s
> (PAGE_SIZE
>>9))
2096 /* Note: no rcu protection needed here
2097 * as this is synchronous in the raid1d thread
2098 * which is the thread that might remove
2099 * a device. If raid1d ever becomes multi-threaded....
2104 rdev
= conf
->mirrors
[d
].rdev
;
2106 (test_bit(In_sync
, &rdev
->flags
) ||
2107 (!test_bit(Faulty
, &rdev
->flags
) &&
2108 rdev
->recovery_offset
>= sect
+ s
)) &&
2109 is_badblock(rdev
, sect
, s
,
2110 &first_bad
, &bad_sectors
) == 0 &&
2111 sync_page_io(rdev
, sect
, s
<<9,
2112 conf
->tmppage
, READ
, false))
2116 if (d
== conf
->raid_disks
* 2)
2119 } while (!success
&& d
!= read_disk
);
2122 /* Cannot read from anywhere - mark it bad */
2123 struct md_rdev
*rdev
= conf
->mirrors
[read_disk
].rdev
;
2124 if (!rdev_set_badblocks(rdev
, sect
, s
, 0))
2125 md_error(mddev
, rdev
);
2128 /* write it back and re-read */
2130 while (d
!= read_disk
) {
2132 d
= conf
->raid_disks
* 2;
2134 rdev
= conf
->mirrors
[d
].rdev
;
2136 test_bit(In_sync
, &rdev
->flags
))
2137 r1_sync_page_io(rdev
, sect
, s
,
2138 conf
->tmppage
, WRITE
);
2141 while (d
!= read_disk
) {
2142 char b
[BDEVNAME_SIZE
];
2144 d
= conf
->raid_disks
* 2;
2146 rdev
= conf
->mirrors
[d
].rdev
;
2148 test_bit(In_sync
, &rdev
->flags
)) {
2149 if (r1_sync_page_io(rdev
, sect
, s
,
2150 conf
->tmppage
, READ
)) {
2151 atomic_add(s
, &rdev
->corrected_errors
);
2153 "md/raid1:%s: read error corrected "
2154 "(%d sectors at %llu on %s)\n",
2156 (unsigned long long)(sect
+
2158 bdevname(rdev
->bdev
, b
));
2167 static int narrow_write_error(struct r1bio
*r1_bio
, int i
)
2169 struct mddev
*mddev
= r1_bio
->mddev
;
2170 struct r1conf
*conf
= mddev
->private;
2171 struct md_rdev
*rdev
= conf
->mirrors
[i
].rdev
;
2173 /* bio has the data to be written to device 'i' where
2174 * we just recently had a write error.
2175 * We repeatedly clone the bio and trim down to one block,
2176 * then try the write. Where the write fails we record
2178 * It is conceivable that the bio doesn't exactly align with
2179 * blocks. We must handle this somehow.
2181 * We currently own a reference on the rdev.
2187 int sect_to_write
= r1_bio
->sectors
;
2190 if (rdev
->badblocks
.shift
< 0)
2193 block_sectors
= 1 << rdev
->badblocks
.shift
;
2194 sector
= r1_bio
->sector
;
2195 sectors
= ((sector
+ block_sectors
)
2196 & ~(sector_t
)(block_sectors
- 1))
2199 while (sect_to_write
) {
2201 if (sectors
> sect_to_write
)
2202 sectors
= sect_to_write
;
2203 /* Write at 'sector' for 'sectors'*/
2205 if (test_bit(R1BIO_BehindIO
, &r1_bio
->state
)) {
2206 unsigned vcnt
= r1_bio
->behind_page_count
;
2207 struct bio_vec
*vec
= r1_bio
->behind_bvecs
;
2209 while (!vec
->bv_page
) {
2214 wbio
= bio_alloc_mddev(GFP_NOIO
, vcnt
, mddev
);
2215 memcpy(wbio
->bi_io_vec
, vec
, vcnt
* sizeof(struct bio_vec
));
2217 wbio
->bi_vcnt
= vcnt
;
2219 wbio
= bio_clone_mddev(r1_bio
->master_bio
, GFP_NOIO
, mddev
);
2222 wbio
->bi_rw
= WRITE
;
2223 wbio
->bi_sector
= r1_bio
->sector
;
2224 wbio
->bi_size
= r1_bio
->sectors
<< 9;
2226 bio_trim(wbio
, sector
- r1_bio
->sector
, sectors
);
2227 wbio
->bi_sector
+= rdev
->data_offset
;
2228 wbio
->bi_bdev
= rdev
->bdev
;
2229 if (submit_bio_wait(WRITE
, wbio
) == 0)
2231 ok
= rdev_set_badblocks(rdev
, sector
,
2236 sect_to_write
-= sectors
;
2238 sectors
= block_sectors
;
2243 static void handle_sync_write_finished(struct r1conf
*conf
, struct r1bio
*r1_bio
)
2246 int s
= r1_bio
->sectors
;
2247 for (m
= 0; m
< conf
->raid_disks
* 2 ; m
++) {
2248 struct md_rdev
*rdev
= conf
->mirrors
[m
].rdev
;
2249 struct bio
*bio
= r1_bio
->bios
[m
];
2250 if (bio
->bi_end_io
== NULL
)
2252 if (test_bit(BIO_UPTODATE
, &bio
->bi_flags
) &&
2253 test_bit(R1BIO_MadeGood
, &r1_bio
->state
)) {
2254 rdev_clear_badblocks(rdev
, r1_bio
->sector
, s
, 0);
2256 if (!test_bit(BIO_UPTODATE
, &bio
->bi_flags
) &&
2257 test_bit(R1BIO_WriteError
, &r1_bio
->state
)) {
2258 if (!rdev_set_badblocks(rdev
, r1_bio
->sector
, s
, 0))
2259 md_error(conf
->mddev
, rdev
);
2263 md_done_sync(conf
->mddev
, s
, 1);
2266 static void handle_write_finished(struct r1conf
*conf
, struct r1bio
*r1_bio
)
2269 for (m
= 0; m
< conf
->raid_disks
* 2 ; m
++)
2270 if (r1_bio
->bios
[m
] == IO_MADE_GOOD
) {
2271 struct md_rdev
*rdev
= conf
->mirrors
[m
].rdev
;
2272 rdev_clear_badblocks(rdev
,
2274 r1_bio
->sectors
, 0);
2275 rdev_dec_pending(rdev
, conf
->mddev
);
2276 } else if (r1_bio
->bios
[m
] != NULL
) {
2277 /* This drive got a write error. We need to
2278 * narrow down and record precise write
2281 if (!narrow_write_error(r1_bio
, m
)) {
2282 md_error(conf
->mddev
,
2283 conf
->mirrors
[m
].rdev
);
2284 /* an I/O failed, we can't clear the bitmap */
2285 set_bit(R1BIO_Degraded
, &r1_bio
->state
);
2287 rdev_dec_pending(conf
->mirrors
[m
].rdev
,
2290 if (test_bit(R1BIO_WriteError
, &r1_bio
->state
))
2291 close_write(r1_bio
);
2292 raid_end_bio_io(r1_bio
);
2295 static void handle_read_error(struct r1conf
*conf
, struct r1bio
*r1_bio
)
2299 struct mddev
*mddev
= conf
->mddev
;
2301 char b
[BDEVNAME_SIZE
];
2302 struct md_rdev
*rdev
;
2304 clear_bit(R1BIO_ReadError
, &r1_bio
->state
);
2305 /* we got a read error. Maybe the drive is bad. Maybe just
2306 * the block and we can fix it.
2307 * We freeze all other IO, and try reading the block from
2308 * other devices. When we find one, we re-write
2309 * and check it that fixes the read error.
2310 * This is all done synchronously while the array is
2313 if (mddev
->ro
== 0) {
2314 freeze_array(conf
, 1);
2315 fix_read_error(conf
, r1_bio
->read_disk
,
2316 r1_bio
->sector
, r1_bio
->sectors
);
2317 unfreeze_array(conf
);
2319 md_error(mddev
, conf
->mirrors
[r1_bio
->read_disk
].rdev
);
2320 rdev_dec_pending(conf
->mirrors
[r1_bio
->read_disk
].rdev
, conf
->mddev
);
2322 bio
= r1_bio
->bios
[r1_bio
->read_disk
];
2323 bdevname(bio
->bi_bdev
, b
);
2325 disk
= read_balance(conf
, r1_bio
, &max_sectors
);
2327 printk(KERN_ALERT
"md/raid1:%s: %s: unrecoverable I/O"
2328 " read error for block %llu\n",
2329 mdname(mddev
), b
, (unsigned long long)r1_bio
->sector
);
2330 raid_end_bio_io(r1_bio
);
2332 const unsigned long do_sync
2333 = r1_bio
->master_bio
->bi_rw
& REQ_SYNC
;
2335 r1_bio
->bios
[r1_bio
->read_disk
] =
2336 mddev
->ro
? IO_BLOCKED
: NULL
;
2339 r1_bio
->read_disk
= disk
;
2340 bio
= bio_clone_mddev(r1_bio
->master_bio
, GFP_NOIO
, mddev
);
2341 bio_trim(bio
, r1_bio
->sector
- bio
->bi_sector
, max_sectors
);
2342 r1_bio
->bios
[r1_bio
->read_disk
] = bio
;
2343 rdev
= conf
->mirrors
[disk
].rdev
;
2344 printk_ratelimited(KERN_ERR
2345 "md/raid1:%s: redirecting sector %llu"
2346 " to other mirror: %s\n",
2348 (unsigned long long)r1_bio
->sector
,
2349 bdevname(rdev
->bdev
, b
));
2350 bio
->bi_sector
= r1_bio
->sector
+ rdev
->data_offset
;
2351 bio
->bi_bdev
= rdev
->bdev
;
2352 bio
->bi_end_io
= raid1_end_read_request
;
2353 bio
->bi_rw
= READ
| do_sync
;
2354 bio
->bi_private
= r1_bio
;
2355 if (max_sectors
< r1_bio
->sectors
) {
2356 /* Drat - have to split this up more */
2357 struct bio
*mbio
= r1_bio
->master_bio
;
2358 int sectors_handled
= (r1_bio
->sector
+ max_sectors
2360 r1_bio
->sectors
= max_sectors
;
2361 spin_lock_irq(&conf
->device_lock
);
2362 if (mbio
->bi_phys_segments
== 0)
2363 mbio
->bi_phys_segments
= 2;
2365 mbio
->bi_phys_segments
++;
2366 spin_unlock_irq(&conf
->device_lock
);
2367 generic_make_request(bio
);
2370 r1_bio
= mempool_alloc(conf
->r1bio_pool
, GFP_NOIO
);
2372 r1_bio
->master_bio
= mbio
;
2373 r1_bio
->sectors
= bio_sectors(mbio
) - sectors_handled
;
2375 set_bit(R1BIO_ReadError
, &r1_bio
->state
);
2376 r1_bio
->mddev
= mddev
;
2377 r1_bio
->sector
= mbio
->bi_sector
+ sectors_handled
;
2381 generic_make_request(bio
);
2385 static void raid1d(struct md_thread
*thread
)
2387 struct mddev
*mddev
= thread
->mddev
;
2388 struct r1bio
*r1_bio
;
2389 unsigned long flags
;
2390 struct r1conf
*conf
= mddev
->private;
2391 struct list_head
*head
= &conf
->retry_list
;
2392 struct blk_plug plug
;
2394 md_check_recovery(mddev
);
2396 blk_start_plug(&plug
);
2399 flush_pending_writes(conf
);
2401 spin_lock_irqsave(&conf
->device_lock
, flags
);
2402 if (list_empty(head
)) {
2403 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
2406 r1_bio
= list_entry(head
->prev
, struct r1bio
, retry_list
);
2407 list_del(head
->prev
);
2409 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
2411 mddev
= r1_bio
->mddev
;
2412 conf
= mddev
->private;
2413 if (test_bit(R1BIO_IsSync
, &r1_bio
->state
)) {
2414 if (test_bit(R1BIO_MadeGood
, &r1_bio
->state
) ||
2415 test_bit(R1BIO_WriteError
, &r1_bio
->state
))
2416 handle_sync_write_finished(conf
, r1_bio
);
2418 sync_request_write(mddev
, r1_bio
);
2419 } else if (test_bit(R1BIO_MadeGood
, &r1_bio
->state
) ||
2420 test_bit(R1BIO_WriteError
, &r1_bio
->state
))
2421 handle_write_finished(conf
, r1_bio
);
2422 else if (test_bit(R1BIO_ReadError
, &r1_bio
->state
))
2423 handle_read_error(conf
, r1_bio
);
2425 /* just a partial read to be scheduled from separate
2428 generic_make_request(r1_bio
->bios
[r1_bio
->read_disk
]);
2431 if (mddev
->flags
& ~(1<<MD_CHANGE_PENDING
))
2432 md_check_recovery(mddev
);
2434 blk_finish_plug(&plug
);
2438 static int init_resync(struct r1conf
*conf
)
2442 buffs
= RESYNC_WINDOW
/ RESYNC_BLOCK_SIZE
;
2443 BUG_ON(conf
->r1buf_pool
);
2444 conf
->r1buf_pool
= mempool_create(buffs
, r1buf_pool_alloc
, r1buf_pool_free
,
2446 if (!conf
->r1buf_pool
)
2448 conf
->next_resync
= 0;
2453 * perform a "sync" on one "block"
2455 * We need to make sure that no normal I/O request - particularly write
2456 * requests - conflict with active sync requests.
2458 * This is achieved by tracking pending requests and a 'barrier' concept
2459 * that can be installed to exclude normal IO requests.
2462 static sector_t
sync_request(struct mddev
*mddev
, sector_t sector_nr
, int *skipped
, int go_faster
)
2464 struct r1conf
*conf
= mddev
->private;
2465 struct r1bio
*r1_bio
;
2467 sector_t max_sector
, nr_sectors
;
2471 int write_targets
= 0, read_targets
= 0;
2472 sector_t sync_blocks
;
2473 int still_degraded
= 0;
2474 int good_sectors
= RESYNC_SECTORS
;
2475 int min_bad
= 0; /* number of sectors that are bad in all devices */
2477 if (!conf
->r1buf_pool
)
2478 if (init_resync(conf
))
2481 max_sector
= mddev
->dev_sectors
;
2482 if (sector_nr
>= max_sector
) {
2483 /* If we aborted, we need to abort the
2484 * sync on the 'current' bitmap chunk (there will
2485 * only be one in raid1 resync.
2486 * We can find the current addess in mddev->curr_resync
2488 if (mddev
->curr_resync
< max_sector
) /* aborted */
2489 bitmap_end_sync(mddev
->bitmap
, mddev
->curr_resync
,
2491 else /* completed sync */
2494 bitmap_close_sync(mddev
->bitmap
);
2499 if (mddev
->bitmap
== NULL
&&
2500 mddev
->recovery_cp
== MaxSector
&&
2501 !test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
) &&
2502 conf
->fullsync
== 0) {
2504 return max_sector
- sector_nr
;
2506 /* before building a request, check if we can skip these blocks..
2507 * This call the bitmap_start_sync doesn't actually record anything
2509 if (!bitmap_start_sync(mddev
->bitmap
, sector_nr
, &sync_blocks
, 1) &&
2510 !conf
->fullsync
&& !test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
)) {
2511 /* We can skip this block, and probably several more */
2516 * If there is non-resync activity waiting for a turn,
2517 * and resync is going fast enough,
2518 * then let it though before starting on this new sync request.
2520 if (!go_faster
&& conf
->nr_waiting
)
2521 msleep_interruptible(1000);
2523 bitmap_cond_end_sync(mddev
->bitmap
, sector_nr
);
2524 r1_bio
= mempool_alloc(conf
->r1buf_pool
, GFP_NOIO
);
2525 raise_barrier(conf
);
2527 conf
->next_resync
= sector_nr
;
2531 * If we get a correctably read error during resync or recovery,
2532 * we might want to read from a different device. So we
2533 * flag all drives that could conceivably be read from for READ,
2534 * and any others (which will be non-In_sync devices) for WRITE.
2535 * If a read fails, we try reading from something else for which READ
2539 r1_bio
->mddev
= mddev
;
2540 r1_bio
->sector
= sector_nr
;
2542 set_bit(R1BIO_IsSync
, &r1_bio
->state
);
2544 for (i
= 0; i
< conf
->raid_disks
* 2; i
++) {
2545 struct md_rdev
*rdev
;
2546 bio
= r1_bio
->bios
[i
];
2549 rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
2551 test_bit(Faulty
, &rdev
->flags
)) {
2552 if (i
< conf
->raid_disks
)
2554 } else if (!test_bit(In_sync
, &rdev
->flags
)) {
2556 bio
->bi_end_io
= end_sync_write
;
2559 /* may need to read from here */
2560 sector_t first_bad
= MaxSector
;
2563 if (is_badblock(rdev
, sector_nr
, good_sectors
,
2564 &first_bad
, &bad_sectors
)) {
2565 if (first_bad
> sector_nr
)
2566 good_sectors
= first_bad
- sector_nr
;
2568 bad_sectors
-= (sector_nr
- first_bad
);
2570 min_bad
> bad_sectors
)
2571 min_bad
= bad_sectors
;
2574 if (sector_nr
< first_bad
) {
2575 if (test_bit(WriteMostly
, &rdev
->flags
)) {
2583 bio
->bi_end_io
= end_sync_read
;
2585 } else if (!test_bit(WriteErrorSeen
, &rdev
->flags
) &&
2586 test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
) &&
2587 !test_bit(MD_RECOVERY_CHECK
, &mddev
->recovery
)) {
2589 * The device is suitable for reading (InSync),
2590 * but has bad block(s) here. Let's try to correct them,
2591 * if we are doing resync or repair. Otherwise, leave
2592 * this device alone for this sync request.
2595 bio
->bi_end_io
= end_sync_write
;
2599 if (bio
->bi_end_io
) {
2600 atomic_inc(&rdev
->nr_pending
);
2601 bio
->bi_sector
= sector_nr
+ rdev
->data_offset
;
2602 bio
->bi_bdev
= rdev
->bdev
;
2603 bio
->bi_private
= r1_bio
;
2609 r1_bio
->read_disk
= disk
;
2611 if (read_targets
== 0 && min_bad
> 0) {
2612 /* These sectors are bad on all InSync devices, so we
2613 * need to mark them bad on all write targets
2616 for (i
= 0 ; i
< conf
->raid_disks
* 2 ; i
++)
2617 if (r1_bio
->bios
[i
]->bi_end_io
== end_sync_write
) {
2618 struct md_rdev
*rdev
= conf
->mirrors
[i
].rdev
;
2619 ok
= rdev_set_badblocks(rdev
, sector_nr
,
2623 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
2628 /* Cannot record the badblocks, so need to
2630 * If there are multiple read targets, could just
2631 * fail the really bad ones ???
2633 conf
->recovery_disabled
= mddev
->recovery_disabled
;
2634 set_bit(MD_RECOVERY_INTR
, &mddev
->recovery
);
2640 if (min_bad
> 0 && min_bad
< good_sectors
) {
2641 /* only resync enough to reach the next bad->good
2643 good_sectors
= min_bad
;
2646 if (test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
) && read_targets
> 0)
2647 /* extra read targets are also write targets */
2648 write_targets
+= read_targets
-1;
2650 if (write_targets
== 0 || read_targets
== 0) {
2651 /* There is nowhere to write, so all non-sync
2652 * drives must be failed - so we are finished
2656 max_sector
= sector_nr
+ min_bad
;
2657 rv
= max_sector
- sector_nr
;
2663 if (max_sector
> mddev
->resync_max
)
2664 max_sector
= mddev
->resync_max
; /* Don't do IO beyond here */
2665 if (max_sector
> sector_nr
+ good_sectors
)
2666 max_sector
= sector_nr
+ good_sectors
;
2671 int len
= PAGE_SIZE
;
2672 if (sector_nr
+ (len
>>9) > max_sector
)
2673 len
= (max_sector
- sector_nr
) << 9;
2676 if (sync_blocks
== 0) {
2677 if (!bitmap_start_sync(mddev
->bitmap
, sector_nr
,
2678 &sync_blocks
, still_degraded
) &&
2680 !test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
))
2682 BUG_ON(sync_blocks
< (PAGE_SIZE
>>9));
2683 if ((len
>> 9) > sync_blocks
)
2684 len
= sync_blocks
<<9;
2687 for (i
= 0 ; i
< conf
->raid_disks
* 2; i
++) {
2688 bio
= r1_bio
->bios
[i
];
2689 if (bio
->bi_end_io
) {
2690 page
= bio
->bi_io_vec
[bio
->bi_vcnt
].bv_page
;
2691 if (bio_add_page(bio
, page
, len
, 0) == 0) {
2693 bio
->bi_io_vec
[bio
->bi_vcnt
].bv_page
= page
;
2696 bio
= r1_bio
->bios
[i
];
2697 if (bio
->bi_end_io
==NULL
)
2699 /* remove last page from this bio */
2701 bio
->bi_size
-= len
;
2702 bio
->bi_flags
&= ~(1<< BIO_SEG_VALID
);
2708 nr_sectors
+= len
>>9;
2709 sector_nr
+= len
>>9;
2710 sync_blocks
-= (len
>>9);
2711 } while (r1_bio
->bios
[disk
]->bi_vcnt
< RESYNC_PAGES
);
2713 r1_bio
->sectors
= nr_sectors
;
2715 /* For a user-requested sync, we read all readable devices and do a
2718 if (test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
)) {
2719 atomic_set(&r1_bio
->remaining
, read_targets
);
2720 for (i
= 0; i
< conf
->raid_disks
* 2 && read_targets
; i
++) {
2721 bio
= r1_bio
->bios
[i
];
2722 if (bio
->bi_end_io
== end_sync_read
) {
2724 md_sync_acct(bio
->bi_bdev
, nr_sectors
);
2725 generic_make_request(bio
);
2729 atomic_set(&r1_bio
->remaining
, 1);
2730 bio
= r1_bio
->bios
[r1_bio
->read_disk
];
2731 md_sync_acct(bio
->bi_bdev
, nr_sectors
);
2732 generic_make_request(bio
);
2738 static sector_t
raid1_size(struct mddev
*mddev
, sector_t sectors
, int raid_disks
)
2743 return mddev
->dev_sectors
;
2746 static struct r1conf
*setup_conf(struct mddev
*mddev
)
2748 struct r1conf
*conf
;
2750 struct raid1_info
*disk
;
2751 struct md_rdev
*rdev
;
2754 conf
= kzalloc(sizeof(struct r1conf
), GFP_KERNEL
);
2758 conf
->mirrors
= kzalloc(sizeof(struct raid1_info
)
2759 * mddev
->raid_disks
* 2,
2764 conf
->tmppage
= alloc_page(GFP_KERNEL
);
2768 conf
->poolinfo
= kzalloc(sizeof(*conf
->poolinfo
), GFP_KERNEL
);
2769 if (!conf
->poolinfo
)
2771 conf
->poolinfo
->raid_disks
= mddev
->raid_disks
* 2;
2772 conf
->r1bio_pool
= mempool_create(NR_RAID1_BIOS
, r1bio_pool_alloc
,
2775 if (!conf
->r1bio_pool
)
2778 conf
->poolinfo
->mddev
= mddev
;
2781 spin_lock_init(&conf
->device_lock
);
2782 rdev_for_each(rdev
, mddev
) {
2783 struct request_queue
*q
;
2784 int disk_idx
= rdev
->raid_disk
;
2785 if (disk_idx
>= mddev
->raid_disks
2788 if (test_bit(Replacement
, &rdev
->flags
))
2789 disk
= conf
->mirrors
+ mddev
->raid_disks
+ disk_idx
;
2791 disk
= conf
->mirrors
+ disk_idx
;
2796 q
= bdev_get_queue(rdev
->bdev
);
2797 if (q
->merge_bvec_fn
)
2798 mddev
->merge_check_needed
= 1;
2800 disk
->head_position
= 0;
2801 disk
->seq_start
= MaxSector
;
2803 conf
->raid_disks
= mddev
->raid_disks
;
2804 conf
->mddev
= mddev
;
2805 INIT_LIST_HEAD(&conf
->retry_list
);
2807 spin_lock_init(&conf
->resync_lock
);
2808 init_waitqueue_head(&conf
->wait_barrier
);
2810 bio_list_init(&conf
->pending_bio_list
);
2811 conf
->pending_count
= 0;
2812 conf
->recovery_disabled
= mddev
->recovery_disabled
- 1;
2814 conf
->start_next_window
= MaxSector
;
2815 conf
->current_window_requests
= conf
->next_window_requests
= 0;
2818 for (i
= 0; i
< conf
->raid_disks
* 2; i
++) {
2820 disk
= conf
->mirrors
+ i
;
2822 if (i
< conf
->raid_disks
&&
2823 disk
[conf
->raid_disks
].rdev
) {
2824 /* This slot has a replacement. */
2826 /* No original, just make the replacement
2827 * a recovering spare
2830 disk
[conf
->raid_disks
].rdev
;
2831 disk
[conf
->raid_disks
].rdev
= NULL
;
2832 } else if (!test_bit(In_sync
, &disk
->rdev
->flags
))
2833 /* Original is not in_sync - bad */
2838 !test_bit(In_sync
, &disk
->rdev
->flags
)) {
2839 disk
->head_position
= 0;
2841 (disk
->rdev
->saved_raid_disk
< 0))
2847 conf
->thread
= md_register_thread(raid1d
, mddev
, "raid1");
2848 if (!conf
->thread
) {
2850 "md/raid1:%s: couldn't allocate thread\n",
2859 if (conf
->r1bio_pool
)
2860 mempool_destroy(conf
->r1bio_pool
);
2861 kfree(conf
->mirrors
);
2862 safe_put_page(conf
->tmppage
);
2863 kfree(conf
->poolinfo
);
2866 return ERR_PTR(err
);
2869 static int stop(struct mddev
*mddev
);
2870 static int run(struct mddev
*mddev
)
2872 struct r1conf
*conf
;
2874 struct md_rdev
*rdev
;
2876 bool discard_supported
= false;
2878 if (mddev
->level
!= 1) {
2879 printk(KERN_ERR
"md/raid1:%s: raid level not set to mirroring (%d)\n",
2880 mdname(mddev
), mddev
->level
);
2883 if (mddev
->reshape_position
!= MaxSector
) {
2884 printk(KERN_ERR
"md/raid1:%s: reshape_position set but not supported\n",
2889 * copy the already verified devices into our private RAID1
2890 * bookkeeping area. [whatever we allocate in run(),
2891 * should be freed in stop()]
2893 if (mddev
->private == NULL
)
2894 conf
= setup_conf(mddev
);
2896 conf
= mddev
->private;
2899 return PTR_ERR(conf
);
2902 blk_queue_max_write_same_sectors(mddev
->queue
, 0);
2904 rdev_for_each(rdev
, mddev
) {
2905 if (!mddev
->gendisk
)
2907 disk_stack_limits(mddev
->gendisk
, rdev
->bdev
,
2908 rdev
->data_offset
<< 9);
2909 if (blk_queue_discard(bdev_get_queue(rdev
->bdev
)))
2910 discard_supported
= true;
2913 mddev
->degraded
= 0;
2914 for (i
=0; i
< conf
->raid_disks
; i
++)
2915 if (conf
->mirrors
[i
].rdev
== NULL
||
2916 !test_bit(In_sync
, &conf
->mirrors
[i
].rdev
->flags
) ||
2917 test_bit(Faulty
, &conf
->mirrors
[i
].rdev
->flags
))
2920 if (conf
->raid_disks
- mddev
->degraded
== 1)
2921 mddev
->recovery_cp
= MaxSector
;
2923 if (mddev
->recovery_cp
!= MaxSector
)
2924 printk(KERN_NOTICE
"md/raid1:%s: not clean"
2925 " -- starting background reconstruction\n",
2928 "md/raid1:%s: active with %d out of %d mirrors\n",
2929 mdname(mddev
), mddev
->raid_disks
- mddev
->degraded
,
2933 * Ok, everything is just fine now
2935 mddev
->thread
= conf
->thread
;
2936 conf
->thread
= NULL
;
2937 mddev
->private = conf
;
2939 md_set_array_sectors(mddev
, raid1_size(mddev
, 0, 0));
2942 mddev
->queue
->backing_dev_info
.congested_fn
= raid1_congested
;
2943 mddev
->queue
->backing_dev_info
.congested_data
= mddev
;
2944 blk_queue_merge_bvec(mddev
->queue
, raid1_mergeable_bvec
);
2946 if (discard_supported
)
2947 queue_flag_set_unlocked(QUEUE_FLAG_DISCARD
,
2950 queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD
,
2954 ret
= md_integrity_register(mddev
);
2960 static int stop(struct mddev
*mddev
)
2962 struct r1conf
*conf
= mddev
->private;
2963 struct bitmap
*bitmap
= mddev
->bitmap
;
2965 /* wait for behind writes to complete */
2966 if (bitmap
&& atomic_read(&bitmap
->behind_writes
) > 0) {
2967 printk(KERN_INFO
"md/raid1:%s: behind writes in progress - waiting to stop.\n",
2969 /* need to kick something here to make sure I/O goes? */
2970 wait_event(bitmap
->behind_wait
,
2971 atomic_read(&bitmap
->behind_writes
) == 0);
2974 freeze_array(conf
, 0);
2975 unfreeze_array(conf
);
2977 md_unregister_thread(&mddev
->thread
);
2978 if (conf
->r1bio_pool
)
2979 mempool_destroy(conf
->r1bio_pool
);
2980 kfree(conf
->mirrors
);
2981 safe_put_page(conf
->tmppage
);
2982 kfree(conf
->poolinfo
);
2984 mddev
->private = NULL
;
2988 static int raid1_resize(struct mddev
*mddev
, sector_t sectors
)
2990 /* no resync is happening, and there is enough space
2991 * on all devices, so we can resize.
2992 * We need to make sure resync covers any new space.
2993 * If the array is shrinking we should possibly wait until
2994 * any io in the removed space completes, but it hardly seems
2997 sector_t newsize
= raid1_size(mddev
, sectors
, 0);
2998 if (mddev
->external_size
&&
2999 mddev
->array_sectors
> newsize
)
3001 if (mddev
->bitmap
) {
3002 int ret
= bitmap_resize(mddev
->bitmap
, newsize
, 0, 0);
3006 md_set_array_sectors(mddev
, newsize
);
3007 set_capacity(mddev
->gendisk
, mddev
->array_sectors
);
3008 revalidate_disk(mddev
->gendisk
);
3009 if (sectors
> mddev
->dev_sectors
&&
3010 mddev
->recovery_cp
> mddev
->dev_sectors
) {
3011 mddev
->recovery_cp
= mddev
->dev_sectors
;
3012 set_bit(MD_RECOVERY_NEEDED
, &mddev
->recovery
);
3014 mddev
->dev_sectors
= sectors
;
3015 mddev
->resync_max_sectors
= sectors
;
3019 static int raid1_reshape(struct mddev
*mddev
)
3022 * 1/ resize the r1bio_pool
3023 * 2/ resize conf->mirrors
3025 * We allocate a new r1bio_pool if we can.
3026 * Then raise a device barrier and wait until all IO stops.
3027 * Then resize conf->mirrors and swap in the new r1bio pool.
3029 * At the same time, we "pack" the devices so that all the missing
3030 * devices have the higher raid_disk numbers.
3032 mempool_t
*newpool
, *oldpool
;
3033 struct pool_info
*newpoolinfo
;
3034 struct raid1_info
*newmirrors
;
3035 struct r1conf
*conf
= mddev
->private;
3036 int cnt
, raid_disks
;
3037 unsigned long flags
;
3040 /* Cannot change chunk_size, layout, or level */
3041 if (mddev
->chunk_sectors
!= mddev
->new_chunk_sectors
||
3042 mddev
->layout
!= mddev
->new_layout
||
3043 mddev
->level
!= mddev
->new_level
) {
3044 mddev
->new_chunk_sectors
= mddev
->chunk_sectors
;
3045 mddev
->new_layout
= mddev
->layout
;
3046 mddev
->new_level
= mddev
->level
;
3050 err
= md_allow_write(mddev
);
3054 raid_disks
= mddev
->raid_disks
+ mddev
->delta_disks
;
3056 if (raid_disks
< conf
->raid_disks
) {
3058 for (d
= 0; d
< conf
->raid_disks
; d
++)
3059 if (conf
->mirrors
[d
].rdev
)
3061 if (cnt
> raid_disks
)
3065 newpoolinfo
= kmalloc(sizeof(*newpoolinfo
), GFP_KERNEL
);
3068 newpoolinfo
->mddev
= mddev
;
3069 newpoolinfo
->raid_disks
= raid_disks
* 2;
3071 newpool
= mempool_create(NR_RAID1_BIOS
, r1bio_pool_alloc
,
3072 r1bio_pool_free
, newpoolinfo
);
3077 newmirrors
= kzalloc(sizeof(struct raid1_info
) * raid_disks
* 2,
3081 mempool_destroy(newpool
);
3085 freeze_array(conf
, 0);
3087 /* ok, everything is stopped */
3088 oldpool
= conf
->r1bio_pool
;
3089 conf
->r1bio_pool
= newpool
;
3091 for (d
= d2
= 0; d
< conf
->raid_disks
; d
++) {
3092 struct md_rdev
*rdev
= conf
->mirrors
[d
].rdev
;
3093 if (rdev
&& rdev
->raid_disk
!= d2
) {
3094 sysfs_unlink_rdev(mddev
, rdev
);
3095 rdev
->raid_disk
= d2
;
3096 sysfs_unlink_rdev(mddev
, rdev
);
3097 if (sysfs_link_rdev(mddev
, rdev
))
3099 "md/raid1:%s: cannot register rd%d\n",
3100 mdname(mddev
), rdev
->raid_disk
);
3103 newmirrors
[d2
++].rdev
= rdev
;
3105 kfree(conf
->mirrors
);
3106 conf
->mirrors
= newmirrors
;
3107 kfree(conf
->poolinfo
);
3108 conf
->poolinfo
= newpoolinfo
;
3110 spin_lock_irqsave(&conf
->device_lock
, flags
);
3111 mddev
->degraded
+= (raid_disks
- conf
->raid_disks
);
3112 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
3113 conf
->raid_disks
= mddev
->raid_disks
= raid_disks
;
3114 mddev
->delta_disks
= 0;
3116 unfreeze_array(conf
);
3118 set_bit(MD_RECOVERY_NEEDED
, &mddev
->recovery
);
3119 md_wakeup_thread(mddev
->thread
);
3121 mempool_destroy(oldpool
);
3125 static void raid1_quiesce(struct mddev
*mddev
, int state
)
3127 struct r1conf
*conf
= mddev
->private;
3130 case 2: /* wake for suspend */
3131 wake_up(&conf
->wait_barrier
);
3134 freeze_array(conf
, 0);
3137 unfreeze_array(conf
);
3142 static void *raid1_takeover(struct mddev
*mddev
)
3144 /* raid1 can take over:
3145 * raid5 with 2 devices, any layout or chunk size
3147 if (mddev
->level
== 5 && mddev
->raid_disks
== 2) {
3148 struct r1conf
*conf
;
3149 mddev
->new_level
= 1;
3150 mddev
->new_layout
= 0;
3151 mddev
->new_chunk_sectors
= 0;
3152 conf
= setup_conf(mddev
);
3154 /* Array must appear to be quiesced */
3155 conf
->array_frozen
= 1;
3158 return ERR_PTR(-EINVAL
);
3161 static struct md_personality raid1_personality
=
3165 .owner
= THIS_MODULE
,
3166 .make_request
= make_request
,
3170 .error_handler
= error
,
3171 .hot_add_disk
= raid1_add_disk
,
3172 .hot_remove_disk
= raid1_remove_disk
,
3173 .spare_active
= raid1_spare_active
,
3174 .sync_request
= sync_request
,
3175 .resize
= raid1_resize
,
3177 .check_reshape
= raid1_reshape
,
3178 .quiesce
= raid1_quiesce
,
3179 .takeover
= raid1_takeover
,
3182 static int __init
raid_init(void)
3184 return register_md_personality(&raid1_personality
);
3187 static void raid_exit(void)
3189 unregister_md_personality(&raid1_personality
);
3192 module_init(raid_init
);
3193 module_exit(raid_exit
);
3194 MODULE_LICENSE("GPL");
3195 MODULE_DESCRIPTION("RAID1 (mirroring) personality for MD");
3196 MODULE_ALIAS("md-personality-3"); /* RAID1 */
3197 MODULE_ALIAS("md-raid1");
3198 MODULE_ALIAS("md-level-1");
3200 module_param(max_queued_requests
, int, S_IRUGO
|S_IWUSR
);