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_iter
.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_iter
.bi_sector
,
269 (unsigned long long) bio_end_sector(bio
) - 1);
271 call_bio_endio(r1_bio
);
277 * Update disk head position estimator based on IRQ completion info.
279 static inline void update_head_pos(int disk
, struct r1bio
*r1_bio
)
281 struct r1conf
*conf
= r1_bio
->mddev
->private;
283 conf
->mirrors
[disk
].head_position
=
284 r1_bio
->sector
+ (r1_bio
->sectors
);
288 * Find the disk number which triggered given bio
290 static int find_bio_disk(struct r1bio
*r1_bio
, struct bio
*bio
)
293 struct r1conf
*conf
= r1_bio
->mddev
->private;
294 int raid_disks
= conf
->raid_disks
;
296 for (mirror
= 0; mirror
< raid_disks
* 2; mirror
++)
297 if (r1_bio
->bios
[mirror
] == bio
)
300 BUG_ON(mirror
== raid_disks
* 2);
301 update_head_pos(mirror
, r1_bio
);
306 static void raid1_end_read_request(struct bio
*bio
, int error
)
308 int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
309 struct r1bio
*r1_bio
= bio
->bi_private
;
311 struct r1conf
*conf
= r1_bio
->mddev
->private;
313 mirror
= r1_bio
->read_disk
;
315 * this branch is our 'one mirror IO has finished' event handler:
317 update_head_pos(mirror
, r1_bio
);
320 set_bit(R1BIO_Uptodate
, &r1_bio
->state
);
322 /* If all other devices have failed, we want to return
323 * the error upwards rather than fail the last device.
324 * Here we redefine "uptodate" to mean "Don't want to retry"
327 spin_lock_irqsave(&conf
->device_lock
, flags
);
328 if (r1_bio
->mddev
->degraded
== conf
->raid_disks
||
329 (r1_bio
->mddev
->degraded
== conf
->raid_disks
-1 &&
330 !test_bit(Faulty
, &conf
->mirrors
[mirror
].rdev
->flags
)))
332 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
336 raid_end_bio_io(r1_bio
);
337 rdev_dec_pending(conf
->mirrors
[mirror
].rdev
, conf
->mddev
);
342 char b
[BDEVNAME_SIZE
];
344 KERN_ERR
"md/raid1:%s: %s: "
345 "rescheduling sector %llu\n",
347 bdevname(conf
->mirrors
[mirror
].rdev
->bdev
,
349 (unsigned long long)r1_bio
->sector
);
350 set_bit(R1BIO_ReadError
, &r1_bio
->state
);
351 reschedule_retry(r1_bio
);
352 /* don't drop the reference on read_disk yet */
356 static void close_write(struct r1bio
*r1_bio
)
358 /* it really is the end of this request */
359 if (test_bit(R1BIO_BehindIO
, &r1_bio
->state
)) {
360 /* free extra copy of the data pages */
361 int i
= r1_bio
->behind_page_count
;
363 safe_put_page(r1_bio
->behind_bvecs
[i
].bv_page
);
364 kfree(r1_bio
->behind_bvecs
);
365 r1_bio
->behind_bvecs
= NULL
;
367 /* clear the bitmap if all writes complete successfully */
368 bitmap_endwrite(r1_bio
->mddev
->bitmap
, r1_bio
->sector
,
370 !test_bit(R1BIO_Degraded
, &r1_bio
->state
),
371 test_bit(R1BIO_BehindIO
, &r1_bio
->state
));
372 md_write_end(r1_bio
->mddev
);
375 static void r1_bio_write_done(struct r1bio
*r1_bio
)
377 if (!atomic_dec_and_test(&r1_bio
->remaining
))
380 if (test_bit(R1BIO_WriteError
, &r1_bio
->state
))
381 reschedule_retry(r1_bio
);
384 if (test_bit(R1BIO_MadeGood
, &r1_bio
->state
))
385 reschedule_retry(r1_bio
);
387 raid_end_bio_io(r1_bio
);
391 static void raid1_end_write_request(struct bio
*bio
, int error
)
393 int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
394 struct r1bio
*r1_bio
= bio
->bi_private
;
395 int mirror
, behind
= test_bit(R1BIO_BehindIO
, &r1_bio
->state
);
396 struct r1conf
*conf
= r1_bio
->mddev
->private;
397 struct bio
*to_put
= NULL
;
399 mirror
= find_bio_disk(r1_bio
, bio
);
402 * 'one mirror IO has finished' event handler:
405 set_bit(WriteErrorSeen
,
406 &conf
->mirrors
[mirror
].rdev
->flags
);
407 if (!test_and_set_bit(WantReplacement
,
408 &conf
->mirrors
[mirror
].rdev
->flags
))
409 set_bit(MD_RECOVERY_NEEDED
, &
410 conf
->mddev
->recovery
);
412 set_bit(R1BIO_WriteError
, &r1_bio
->state
);
415 * Set R1BIO_Uptodate in our master bio, so that we
416 * will return a good error code for to the higher
417 * levels even if IO on some other mirrored buffer
420 * The 'master' represents the composite IO operation
421 * to user-side. So if something waits for IO, then it
422 * will wait for the 'master' bio.
427 r1_bio
->bios
[mirror
] = NULL
;
430 * Do not set R1BIO_Uptodate if the current device is
431 * rebuilding or Faulty. This is because we cannot use
432 * such device for properly reading the data back (we could
433 * potentially use it, if the current write would have felt
434 * before rdev->recovery_offset, but for simplicity we don't
437 if (test_bit(In_sync
, &conf
->mirrors
[mirror
].rdev
->flags
) &&
438 !test_bit(Faulty
, &conf
->mirrors
[mirror
].rdev
->flags
))
439 set_bit(R1BIO_Uptodate
, &r1_bio
->state
);
441 /* Maybe we can clear some bad blocks. */
442 if (is_badblock(conf
->mirrors
[mirror
].rdev
,
443 r1_bio
->sector
, r1_bio
->sectors
,
444 &first_bad
, &bad_sectors
)) {
445 r1_bio
->bios
[mirror
] = IO_MADE_GOOD
;
446 set_bit(R1BIO_MadeGood
, &r1_bio
->state
);
451 if (test_bit(WriteMostly
, &conf
->mirrors
[mirror
].rdev
->flags
))
452 atomic_dec(&r1_bio
->behind_remaining
);
455 * In behind mode, we ACK the master bio once the I/O
456 * has safely reached all non-writemostly
457 * disks. Setting the Returned bit ensures that this
458 * gets done only once -- we don't ever want to return
459 * -EIO here, instead we'll wait
461 if (atomic_read(&r1_bio
->behind_remaining
) >= (atomic_read(&r1_bio
->remaining
)-1) &&
462 test_bit(R1BIO_Uptodate
, &r1_bio
->state
)) {
463 /* Maybe we can return now */
464 if (!test_and_set_bit(R1BIO_Returned
, &r1_bio
->state
)) {
465 struct bio
*mbio
= r1_bio
->master_bio
;
466 pr_debug("raid1: behind end write sectors"
468 (unsigned long long) mbio
->bi_iter
.bi_sector
,
469 (unsigned long long) bio_end_sector(mbio
) - 1);
470 call_bio_endio(r1_bio
);
474 if (r1_bio
->bios
[mirror
] == NULL
)
475 rdev_dec_pending(conf
->mirrors
[mirror
].rdev
,
479 * Let's see if all mirrored write operations have finished
482 r1_bio_write_done(r1_bio
);
490 * This routine returns the disk from which the requested read should
491 * be done. There is a per-array 'next expected sequential IO' sector
492 * number - if this matches on the next IO then we use the last disk.
493 * There is also a per-disk 'last know head position' sector that is
494 * maintained from IRQ contexts, both the normal and the resync IO
495 * completion handlers update this position correctly. If there is no
496 * perfect sequential match then we pick the disk whose head is closest.
498 * If there are 2 mirrors in the same 2 devices, performance degrades
499 * because position is mirror, not device based.
501 * The rdev for the device selected will have nr_pending incremented.
503 static int read_balance(struct r1conf
*conf
, struct r1bio
*r1_bio
, int *max_sectors
)
505 const sector_t this_sector
= r1_bio
->sector
;
507 int best_good_sectors
;
508 int best_disk
, best_dist_disk
, best_pending_disk
;
512 unsigned int min_pending
;
513 struct md_rdev
*rdev
;
515 int choose_next_idle
;
519 * Check if we can balance. We can balance on the whole
520 * device if no resync is going on, or below the resync window.
521 * We take the first readable disk when above the resync window.
524 sectors
= r1_bio
->sectors
;
527 best_dist
= MaxSector
;
528 best_pending_disk
= -1;
529 min_pending
= UINT_MAX
;
530 best_good_sectors
= 0;
532 choose_next_idle
= 0;
534 if (conf
->mddev
->recovery_cp
< MaxSector
&&
535 (this_sector
+ sectors
>= conf
->next_resync
))
540 for (disk
= 0 ; disk
< conf
->raid_disks
* 2 ; disk
++) {
544 unsigned int pending
;
547 rdev
= rcu_dereference(conf
->mirrors
[disk
].rdev
);
548 if (r1_bio
->bios
[disk
] == IO_BLOCKED
550 || test_bit(Unmerged
, &rdev
->flags
)
551 || test_bit(Faulty
, &rdev
->flags
))
553 if (!test_bit(In_sync
, &rdev
->flags
) &&
554 rdev
->recovery_offset
< this_sector
+ sectors
)
556 if (test_bit(WriteMostly
, &rdev
->flags
)) {
557 /* Don't balance among write-mostly, just
558 * use the first as a last resort */
560 if (is_badblock(rdev
, this_sector
, sectors
,
561 &first_bad
, &bad_sectors
)) {
562 if (first_bad
< this_sector
)
563 /* Cannot use this */
565 best_good_sectors
= first_bad
- this_sector
;
567 best_good_sectors
= sectors
;
572 /* This is a reasonable device to use. It might
575 if (is_badblock(rdev
, this_sector
, sectors
,
576 &first_bad
, &bad_sectors
)) {
577 if (best_dist
< MaxSector
)
578 /* already have a better device */
580 if (first_bad
<= this_sector
) {
581 /* cannot read here. If this is the 'primary'
582 * device, then we must not read beyond
583 * bad_sectors from another device..
585 bad_sectors
-= (this_sector
- first_bad
);
586 if (choose_first
&& sectors
> bad_sectors
)
587 sectors
= bad_sectors
;
588 if (best_good_sectors
> sectors
)
589 best_good_sectors
= sectors
;
592 sector_t good_sectors
= first_bad
- this_sector
;
593 if (good_sectors
> best_good_sectors
) {
594 best_good_sectors
= good_sectors
;
602 best_good_sectors
= sectors
;
604 nonrot
= blk_queue_nonrot(bdev_get_queue(rdev
->bdev
));
605 has_nonrot_disk
|= nonrot
;
606 pending
= atomic_read(&rdev
->nr_pending
);
607 dist
= abs(this_sector
- conf
->mirrors
[disk
].head_position
);
612 /* Don't change to another disk for sequential reads */
613 if (conf
->mirrors
[disk
].next_seq_sect
== this_sector
615 int opt_iosize
= bdev_io_opt(rdev
->bdev
) >> 9;
616 struct raid1_info
*mirror
= &conf
->mirrors
[disk
];
620 * If buffered sequential IO size exceeds optimal
621 * iosize, check if there is idle disk. If yes, choose
622 * the idle disk. read_balance could already choose an
623 * idle disk before noticing it's a sequential IO in
624 * this disk. This doesn't matter because this disk
625 * will idle, next time it will be utilized after the
626 * first disk has IO size exceeds optimal iosize. In
627 * this way, iosize of the first disk will be optimal
628 * iosize at least. iosize of the second disk might be
629 * small, but not a big deal since when the second disk
630 * starts IO, the first disk is likely still busy.
632 if (nonrot
&& opt_iosize
> 0 &&
633 mirror
->seq_start
!= MaxSector
&&
634 mirror
->next_seq_sect
> opt_iosize
&&
635 mirror
->next_seq_sect
- opt_iosize
>=
637 choose_next_idle
= 1;
642 /* If device is idle, use it */
648 if (choose_next_idle
)
651 if (min_pending
> pending
) {
652 min_pending
= pending
;
653 best_pending_disk
= disk
;
656 if (dist
< best_dist
) {
658 best_dist_disk
= disk
;
663 * If all disks are rotational, choose the closest disk. If any disk is
664 * non-rotational, choose the disk with less pending request even the
665 * disk is rotational, which might/might not be optimal for raids with
666 * mixed ratation/non-rotational disks depending on workload.
668 if (best_disk
== -1) {
670 best_disk
= best_pending_disk
;
672 best_disk
= best_dist_disk
;
675 if (best_disk
>= 0) {
676 rdev
= rcu_dereference(conf
->mirrors
[best_disk
].rdev
);
679 atomic_inc(&rdev
->nr_pending
);
680 if (test_bit(Faulty
, &rdev
->flags
)) {
681 /* cannot risk returning a device that failed
682 * before we inc'ed nr_pending
684 rdev_dec_pending(rdev
, conf
->mddev
);
687 sectors
= best_good_sectors
;
689 if (conf
->mirrors
[best_disk
].next_seq_sect
!= this_sector
)
690 conf
->mirrors
[best_disk
].seq_start
= this_sector
;
692 conf
->mirrors
[best_disk
].next_seq_sect
= this_sector
+ sectors
;
695 *max_sectors
= sectors
;
700 static int raid1_mergeable_bvec(struct request_queue
*q
,
701 struct bvec_merge_data
*bvm
,
702 struct bio_vec
*biovec
)
704 struct mddev
*mddev
= q
->queuedata
;
705 struct r1conf
*conf
= mddev
->private;
706 sector_t sector
= bvm
->bi_sector
+ get_start_sect(bvm
->bi_bdev
);
707 int max
= biovec
->bv_len
;
709 if (mddev
->merge_check_needed
) {
712 for (disk
= 0; disk
< conf
->raid_disks
* 2; disk
++) {
713 struct md_rdev
*rdev
= rcu_dereference(
714 conf
->mirrors
[disk
].rdev
);
715 if (rdev
&& !test_bit(Faulty
, &rdev
->flags
)) {
716 struct request_queue
*q
=
717 bdev_get_queue(rdev
->bdev
);
718 if (q
->merge_bvec_fn
) {
719 bvm
->bi_sector
= sector
+
721 bvm
->bi_bdev
= rdev
->bdev
;
722 max
= min(max
, q
->merge_bvec_fn(
733 int md_raid1_congested(struct mddev
*mddev
, int bits
)
735 struct r1conf
*conf
= mddev
->private;
738 if ((bits
& (1 << BDI_async_congested
)) &&
739 conf
->pending_count
>= max_queued_requests
)
743 for (i
= 0; i
< conf
->raid_disks
* 2; i
++) {
744 struct md_rdev
*rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
745 if (rdev
&& !test_bit(Faulty
, &rdev
->flags
)) {
746 struct request_queue
*q
= bdev_get_queue(rdev
->bdev
);
750 /* Note the '|| 1' - when read_balance prefers
751 * non-congested targets, it can be removed
753 if ((bits
& (1<<BDI_async_congested
)) || 1)
754 ret
|= bdi_congested(&q
->backing_dev_info
, bits
);
756 ret
&= bdi_congested(&q
->backing_dev_info
, bits
);
762 EXPORT_SYMBOL_GPL(md_raid1_congested
);
764 static int raid1_congested(void *data
, int bits
)
766 struct mddev
*mddev
= data
;
768 return mddev_congested(mddev
, bits
) ||
769 md_raid1_congested(mddev
, bits
);
772 static void flush_pending_writes(struct r1conf
*conf
)
774 /* Any writes that have been queued but are awaiting
775 * bitmap updates get flushed here.
777 spin_lock_irq(&conf
->device_lock
);
779 if (conf
->pending_bio_list
.head
) {
781 bio
= bio_list_get(&conf
->pending_bio_list
);
782 conf
->pending_count
= 0;
783 spin_unlock_irq(&conf
->device_lock
);
784 /* flush any pending bitmap writes to
785 * disk before proceeding w/ I/O */
786 bitmap_unplug(conf
->mddev
->bitmap
);
787 wake_up(&conf
->wait_barrier
);
789 while (bio
) { /* submit pending writes */
790 struct bio
*next
= bio
->bi_next
;
792 if (unlikely((bio
->bi_rw
& REQ_DISCARD
) &&
793 !blk_queue_discard(bdev_get_queue(bio
->bi_bdev
))))
797 generic_make_request(bio
);
801 spin_unlock_irq(&conf
->device_lock
);
805 * Sometimes we need to suspend IO while we do something else,
806 * either some resync/recovery, or reconfigure the array.
807 * To do this we raise a 'barrier'.
808 * The 'barrier' is a counter that can be raised multiple times
809 * to count how many activities are happening which preclude
811 * We can only raise the barrier if there is no pending IO.
812 * i.e. if nr_pending == 0.
813 * We choose only to raise the barrier if no-one is waiting for the
814 * barrier to go down. This means that as soon as an IO request
815 * is ready, no other operations which require a barrier will start
816 * until the IO request has had a chance.
818 * So: regular IO calls 'wait_barrier'. When that returns there
819 * is no backgroup IO happening, It must arrange to call
820 * allow_barrier when it has finished its IO.
821 * backgroup IO calls must call raise_barrier. Once that returns
822 * there is no normal IO happeing. It must arrange to call
823 * lower_barrier when the particular background IO completes.
825 static void raise_barrier(struct r1conf
*conf
)
827 spin_lock_irq(&conf
->resync_lock
);
829 /* Wait until no block IO is waiting */
830 wait_event_lock_irq(conf
->wait_barrier
, !conf
->nr_waiting
,
833 /* block any new IO from starting */
836 /* For these conditions we must wait:
837 * A: while the array is in frozen state
838 * B: while barrier >= RESYNC_DEPTH, meaning resync reach
839 * the max count which allowed.
840 * C: next_resync + RESYNC_SECTORS > start_next_window, meaning
841 * next resync will reach to the window which normal bios are
844 wait_event_lock_irq(conf
->wait_barrier
,
845 !conf
->array_frozen
&&
846 conf
->barrier
< RESYNC_DEPTH
&&
847 (conf
->start_next_window
>=
848 conf
->next_resync
+ RESYNC_SECTORS
),
851 spin_unlock_irq(&conf
->resync_lock
);
854 static void lower_barrier(struct r1conf
*conf
)
857 BUG_ON(conf
->barrier
<= 0);
858 spin_lock_irqsave(&conf
->resync_lock
, flags
);
860 spin_unlock_irqrestore(&conf
->resync_lock
, flags
);
861 wake_up(&conf
->wait_barrier
);
864 static bool need_to_wait_for_sync(struct r1conf
*conf
, struct bio
*bio
)
868 if (conf
->array_frozen
|| !bio
)
870 else if (conf
->barrier
&& bio_data_dir(bio
) == WRITE
) {
871 if (conf
->next_resync
< RESYNC_WINDOW_SECTORS
)
873 else if ((conf
->next_resync
- RESYNC_WINDOW_SECTORS
874 >= bio_end_sector(bio
)) ||
875 (conf
->next_resync
+ NEXT_NORMALIO_DISTANCE
876 <= bio
->bi_iter
.bi_sector
))
885 static sector_t
wait_barrier(struct r1conf
*conf
, struct bio
*bio
)
889 spin_lock_irq(&conf
->resync_lock
);
890 if (need_to_wait_for_sync(conf
, bio
)) {
892 /* Wait for the barrier to drop.
893 * However if there are already pending
894 * requests (preventing the barrier from
895 * rising completely), and the
896 * pre-process bio queue isn't empty,
897 * then don't wait, as we need to empty
898 * that queue to get the nr_pending
901 wait_event_lock_irq(conf
->wait_barrier
,
902 !conf
->array_frozen
&&
904 ((conf
->start_next_window
<
905 conf
->next_resync
+ RESYNC_SECTORS
) &&
907 !bio_list_empty(current
->bio_list
))),
912 if (bio
&& bio_data_dir(bio
) == WRITE
) {
913 if (conf
->next_resync
+ NEXT_NORMALIO_DISTANCE
914 <= bio
->bi_iter
.bi_sector
) {
915 if (conf
->start_next_window
== MaxSector
)
916 conf
->start_next_window
=
918 NEXT_NORMALIO_DISTANCE
;
920 if ((conf
->start_next_window
+ NEXT_NORMALIO_DISTANCE
)
921 <= bio
->bi_iter
.bi_sector
)
922 conf
->next_window_requests
++;
924 conf
->current_window_requests
++;
926 if (bio
->bi_iter
.bi_sector
>= conf
->start_next_window
)
927 sector
= conf
->start_next_window
;
931 spin_unlock_irq(&conf
->resync_lock
);
935 static void allow_barrier(struct r1conf
*conf
, sector_t start_next_window
,
940 spin_lock_irqsave(&conf
->resync_lock
, flags
);
942 if (start_next_window
) {
943 if (start_next_window
== conf
->start_next_window
) {
944 if (conf
->start_next_window
+ NEXT_NORMALIO_DISTANCE
946 conf
->next_window_requests
--;
948 conf
->current_window_requests
--;
950 conf
->current_window_requests
--;
952 if (!conf
->current_window_requests
) {
953 if (conf
->next_window_requests
) {
954 conf
->current_window_requests
=
955 conf
->next_window_requests
;
956 conf
->next_window_requests
= 0;
957 conf
->start_next_window
+=
958 NEXT_NORMALIO_DISTANCE
;
960 conf
->start_next_window
= MaxSector
;
963 spin_unlock_irqrestore(&conf
->resync_lock
, flags
);
964 wake_up(&conf
->wait_barrier
);
967 static void freeze_array(struct r1conf
*conf
, int extra
)
969 /* stop syncio and normal IO and wait for everything to
971 * We wait until nr_pending match nr_queued+extra
972 * This is called in the context of one normal IO request
973 * that has failed. Thus any sync request that might be pending
974 * will be blocked by nr_pending, and we need to wait for
975 * pending IO requests to complete or be queued for re-try.
976 * Thus the number queued (nr_queued) plus this request (extra)
977 * must match the number of pending IOs (nr_pending) before
980 spin_lock_irq(&conf
->resync_lock
);
981 conf
->array_frozen
= 1;
982 wait_event_lock_irq_cmd(conf
->wait_barrier
,
983 conf
->nr_pending
== conf
->nr_queued
+extra
,
985 flush_pending_writes(conf
));
986 spin_unlock_irq(&conf
->resync_lock
);
988 static void unfreeze_array(struct r1conf
*conf
)
990 /* reverse the effect of the freeze */
991 spin_lock_irq(&conf
->resync_lock
);
992 conf
->array_frozen
= 0;
993 wake_up(&conf
->wait_barrier
);
994 spin_unlock_irq(&conf
->resync_lock
);
998 /* duplicate the data pages for behind I/O
1000 static void alloc_behind_pages(struct bio
*bio
, struct r1bio
*r1_bio
)
1003 struct bio_vec
*bvec
;
1004 struct bio_vec
*bvecs
= kzalloc(bio
->bi_vcnt
* sizeof(struct bio_vec
),
1006 if (unlikely(!bvecs
))
1009 bio_for_each_segment_all(bvec
, bio
, i
) {
1011 bvecs
[i
].bv_page
= alloc_page(GFP_NOIO
);
1012 if (unlikely(!bvecs
[i
].bv_page
))
1014 memcpy(kmap(bvecs
[i
].bv_page
) + bvec
->bv_offset
,
1015 kmap(bvec
->bv_page
) + bvec
->bv_offset
, bvec
->bv_len
);
1016 kunmap(bvecs
[i
].bv_page
);
1017 kunmap(bvec
->bv_page
);
1019 r1_bio
->behind_bvecs
= bvecs
;
1020 r1_bio
->behind_page_count
= bio
->bi_vcnt
;
1021 set_bit(R1BIO_BehindIO
, &r1_bio
->state
);
1025 for (i
= 0; i
< bio
->bi_vcnt
; i
++)
1026 if (bvecs
[i
].bv_page
)
1027 put_page(bvecs
[i
].bv_page
);
1029 pr_debug("%dB behind alloc failed, doing sync I/O\n",
1030 bio
->bi_iter
.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_iter
.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_iter
.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_iter
.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_iter
.bi_sector
,
1186 r1_bio
->bios
[rdisk
] = read_bio
;
1188 read_bio
->bi_iter
.bi_sector
= r1_bio
->sector
+
1189 mirror
->rdev
->data_offset
;
1190 read_bio
->bi_bdev
= mirror
->rdev
->bdev
;
1191 read_bio
->bi_end_io
= raid1_end_read_request
;
1192 read_bio
->bi_rw
= READ
| do_sync
;
1193 read_bio
->bi_private
= r1_bio
;
1195 if (max_sectors
< r1_bio
->sectors
) {
1196 /* could not read all from this device, so we will
1197 * need another r1_bio.
1200 sectors_handled
= (r1_bio
->sector
+ max_sectors
1201 - bio
->bi_iter
.bi_sector
);
1202 r1_bio
->sectors
= max_sectors
;
1203 spin_lock_irq(&conf
->device_lock
);
1204 if (bio
->bi_phys_segments
== 0)
1205 bio
->bi_phys_segments
= 2;
1207 bio
->bi_phys_segments
++;
1208 spin_unlock_irq(&conf
->device_lock
);
1209 /* Cannot call generic_make_request directly
1210 * as that will be queued in __make_request
1211 * and subsequent mempool_alloc might block waiting
1212 * for it. So hand bio over to raid1d.
1214 reschedule_retry(r1_bio
);
1216 r1_bio
= mempool_alloc(conf
->r1bio_pool
, GFP_NOIO
);
1218 r1_bio
->master_bio
= bio
;
1219 r1_bio
->sectors
= bio_sectors(bio
) - sectors_handled
;
1221 r1_bio
->mddev
= mddev
;
1222 r1_bio
->sector
= bio
->bi_iter
.bi_sector
+
1226 generic_make_request(read_bio
);
1233 if (conf
->pending_count
>= max_queued_requests
) {
1234 md_wakeup_thread(mddev
->thread
);
1235 wait_event(conf
->wait_barrier
,
1236 conf
->pending_count
< max_queued_requests
);
1238 /* first select target devices under rcu_lock and
1239 * inc refcount on their rdev. Record them by setting
1241 * If there are known/acknowledged bad blocks on any device on
1242 * which we have seen a write error, we want to avoid writing those
1244 * This potentially requires several writes to write around
1245 * the bad blocks. Each set of writes gets it's own r1bio
1246 * with a set of bios attached.
1249 disks
= conf
->raid_disks
* 2;
1251 r1_bio
->start_next_window
= start_next_window
;
1252 blocked_rdev
= NULL
;
1254 max_sectors
= r1_bio
->sectors
;
1255 for (i
= 0; i
< disks
; i
++) {
1256 struct md_rdev
*rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
1257 if (rdev
&& unlikely(test_bit(Blocked
, &rdev
->flags
))) {
1258 atomic_inc(&rdev
->nr_pending
);
1259 blocked_rdev
= rdev
;
1262 r1_bio
->bios
[i
] = NULL
;
1263 if (!rdev
|| test_bit(Faulty
, &rdev
->flags
)
1264 || test_bit(Unmerged
, &rdev
->flags
)) {
1265 if (i
< conf
->raid_disks
)
1266 set_bit(R1BIO_Degraded
, &r1_bio
->state
);
1270 atomic_inc(&rdev
->nr_pending
);
1271 if (test_bit(WriteErrorSeen
, &rdev
->flags
)) {
1276 is_bad
= is_badblock(rdev
, r1_bio
->sector
,
1278 &first_bad
, &bad_sectors
);
1280 /* mustn't write here until the bad block is
1282 set_bit(BlockedBadBlocks
, &rdev
->flags
);
1283 blocked_rdev
= rdev
;
1286 if (is_bad
&& first_bad
<= r1_bio
->sector
) {
1287 /* Cannot write here at all */
1288 bad_sectors
-= (r1_bio
->sector
- first_bad
);
1289 if (bad_sectors
< max_sectors
)
1290 /* mustn't write more than bad_sectors
1291 * to other devices yet
1293 max_sectors
= bad_sectors
;
1294 rdev_dec_pending(rdev
, mddev
);
1295 /* We don't set R1BIO_Degraded as that
1296 * only applies if the disk is
1297 * missing, so it might be re-added,
1298 * and we want to know to recover this
1300 * In this case the device is here,
1301 * and the fact that this chunk is not
1302 * in-sync is recorded in the bad
1308 int good_sectors
= first_bad
- r1_bio
->sector
;
1309 if (good_sectors
< max_sectors
)
1310 max_sectors
= good_sectors
;
1313 r1_bio
->bios
[i
] = bio
;
1317 if (unlikely(blocked_rdev
)) {
1318 /* Wait for this device to become unblocked */
1320 sector_t old
= start_next_window
;
1322 for (j
= 0; j
< i
; j
++)
1323 if (r1_bio
->bios
[j
])
1324 rdev_dec_pending(conf
->mirrors
[j
].rdev
, mddev
);
1326 allow_barrier(conf
, start_next_window
, bio
->bi_iter
.bi_sector
);
1327 md_wait_for_blocked_rdev(blocked_rdev
, mddev
);
1328 start_next_window
= wait_barrier(conf
, bio
);
1330 * We must make sure the multi r1bios of bio have
1331 * the same value of bi_phys_segments
1333 if (bio
->bi_phys_segments
&& old
&&
1334 old
!= start_next_window
)
1335 /* Wait for the former r1bio(s) to complete */
1336 wait_event(conf
->wait_barrier
,
1337 bio
->bi_phys_segments
== 1);
1341 if (max_sectors
< r1_bio
->sectors
) {
1342 /* We are splitting this write into multiple parts, so
1343 * we need to prepare for allocating another r1_bio.
1345 r1_bio
->sectors
= max_sectors
;
1346 spin_lock_irq(&conf
->device_lock
);
1347 if (bio
->bi_phys_segments
== 0)
1348 bio
->bi_phys_segments
= 2;
1350 bio
->bi_phys_segments
++;
1351 spin_unlock_irq(&conf
->device_lock
);
1353 sectors_handled
= r1_bio
->sector
+ max_sectors
- bio
->bi_iter
.bi_sector
;
1355 atomic_set(&r1_bio
->remaining
, 1);
1356 atomic_set(&r1_bio
->behind_remaining
, 0);
1359 for (i
= 0; i
< disks
; i
++) {
1361 if (!r1_bio
->bios
[i
])
1364 mbio
= bio_clone_mddev(bio
, GFP_NOIO
, mddev
);
1365 bio_trim(mbio
, r1_bio
->sector
- bio
->bi_iter
.bi_sector
, max_sectors
);
1369 * Not if there are too many, or cannot
1370 * allocate memory, or a reader on WriteMostly
1371 * is waiting for behind writes to flush */
1373 (atomic_read(&bitmap
->behind_writes
)
1374 < mddev
->bitmap_info
.max_write_behind
) &&
1375 !waitqueue_active(&bitmap
->behind_wait
))
1376 alloc_behind_pages(mbio
, r1_bio
);
1378 bitmap_startwrite(bitmap
, r1_bio
->sector
,
1380 test_bit(R1BIO_BehindIO
,
1384 if (r1_bio
->behind_bvecs
) {
1385 struct bio_vec
*bvec
;
1389 * We trimmed the bio, so _all is legit
1391 bio_for_each_segment_all(bvec
, mbio
, j
)
1392 bvec
->bv_page
= r1_bio
->behind_bvecs
[j
].bv_page
;
1393 if (test_bit(WriteMostly
, &conf
->mirrors
[i
].rdev
->flags
))
1394 atomic_inc(&r1_bio
->behind_remaining
);
1397 r1_bio
->bios
[i
] = mbio
;
1399 mbio
->bi_iter
.bi_sector
= (r1_bio
->sector
+
1400 conf
->mirrors
[i
].rdev
->data_offset
);
1401 mbio
->bi_bdev
= conf
->mirrors
[i
].rdev
->bdev
;
1402 mbio
->bi_end_io
= raid1_end_write_request
;
1404 WRITE
| do_flush_fua
| do_sync
| do_discard
| do_same
;
1405 mbio
->bi_private
= r1_bio
;
1407 atomic_inc(&r1_bio
->remaining
);
1409 cb
= blk_check_plugged(raid1_unplug
, mddev
, sizeof(*plug
));
1411 plug
= container_of(cb
, struct raid1_plug_cb
, cb
);
1414 spin_lock_irqsave(&conf
->device_lock
, flags
);
1416 bio_list_add(&plug
->pending
, mbio
);
1417 plug
->pending_cnt
++;
1419 bio_list_add(&conf
->pending_bio_list
, mbio
);
1420 conf
->pending_count
++;
1422 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
1424 md_wakeup_thread(mddev
->thread
);
1426 /* Mustn't call r1_bio_write_done before this next test,
1427 * as it could result in the bio being freed.
1429 if (sectors_handled
< bio_sectors(bio
)) {
1430 r1_bio_write_done(r1_bio
);
1431 /* We need another r1_bio. It has already been counted
1432 * in bio->bi_phys_segments
1434 r1_bio
= mempool_alloc(conf
->r1bio_pool
, GFP_NOIO
);
1435 r1_bio
->master_bio
= bio
;
1436 r1_bio
->sectors
= bio_sectors(bio
) - sectors_handled
;
1438 r1_bio
->mddev
= mddev
;
1439 r1_bio
->sector
= bio
->bi_iter
.bi_sector
+ sectors_handled
;
1443 r1_bio_write_done(r1_bio
);
1445 /* In case raid1d snuck in to freeze_array */
1446 wake_up(&conf
->wait_barrier
);
1449 static void status(struct seq_file
*seq
, struct mddev
*mddev
)
1451 struct r1conf
*conf
= mddev
->private;
1454 seq_printf(seq
, " [%d/%d] [", conf
->raid_disks
,
1455 conf
->raid_disks
- mddev
->degraded
);
1457 for (i
= 0; i
< conf
->raid_disks
; i
++) {
1458 struct md_rdev
*rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
1459 seq_printf(seq
, "%s",
1460 rdev
&& test_bit(In_sync
, &rdev
->flags
) ? "U" : "_");
1463 seq_printf(seq
, "]");
1467 static void error(struct mddev
*mddev
, struct md_rdev
*rdev
)
1469 char b
[BDEVNAME_SIZE
];
1470 struct r1conf
*conf
= mddev
->private;
1473 * If it is not operational, then we have already marked it as dead
1474 * else if it is the last working disks, ignore the error, let the
1475 * next level up know.
1476 * else mark the drive as failed
1478 if (test_bit(In_sync
, &rdev
->flags
)
1479 && (conf
->raid_disks
- mddev
->degraded
) == 1) {
1481 * Don't fail the drive, act as though we were just a
1482 * normal single drive.
1483 * However don't try a recovery from this drive as
1484 * it is very likely to fail.
1486 conf
->recovery_disabled
= mddev
->recovery_disabled
;
1489 set_bit(Blocked
, &rdev
->flags
);
1490 if (test_and_clear_bit(In_sync
, &rdev
->flags
)) {
1491 unsigned long flags
;
1492 spin_lock_irqsave(&conf
->device_lock
, flags
);
1494 set_bit(Faulty
, &rdev
->flags
);
1495 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
1497 * if recovery is running, make sure it aborts.
1499 set_bit(MD_RECOVERY_INTR
, &mddev
->recovery
);
1501 set_bit(Faulty
, &rdev
->flags
);
1502 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
1504 "md/raid1:%s: Disk failure on %s, disabling device.\n"
1505 "md/raid1:%s: Operation continuing on %d devices.\n",
1506 mdname(mddev
), bdevname(rdev
->bdev
, b
),
1507 mdname(mddev
), conf
->raid_disks
- mddev
->degraded
);
1510 static void print_conf(struct r1conf
*conf
)
1514 printk(KERN_DEBUG
"RAID1 conf printout:\n");
1516 printk(KERN_DEBUG
"(!conf)\n");
1519 printk(KERN_DEBUG
" --- wd:%d rd:%d\n", conf
->raid_disks
- conf
->mddev
->degraded
,
1523 for (i
= 0; i
< conf
->raid_disks
; i
++) {
1524 char b
[BDEVNAME_SIZE
];
1525 struct md_rdev
*rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
1527 printk(KERN_DEBUG
" disk %d, wo:%d, o:%d, dev:%s\n",
1528 i
, !test_bit(In_sync
, &rdev
->flags
),
1529 !test_bit(Faulty
, &rdev
->flags
),
1530 bdevname(rdev
->bdev
,b
));
1535 static void close_sync(struct r1conf
*conf
)
1537 wait_barrier(conf
, NULL
);
1538 allow_barrier(conf
, 0, 0);
1540 mempool_destroy(conf
->r1buf_pool
);
1541 conf
->r1buf_pool
= NULL
;
1543 conf
->next_resync
= 0;
1544 conf
->start_next_window
= MaxSector
;
1547 static int raid1_spare_active(struct mddev
*mddev
)
1550 struct r1conf
*conf
= mddev
->private;
1552 unsigned long flags
;
1555 * Find all failed disks within the RAID1 configuration
1556 * and mark them readable.
1557 * Called under mddev lock, so rcu protection not needed.
1559 for (i
= 0; i
< conf
->raid_disks
; i
++) {
1560 struct md_rdev
*rdev
= conf
->mirrors
[i
].rdev
;
1561 struct md_rdev
*repl
= conf
->mirrors
[conf
->raid_disks
+ i
].rdev
;
1563 && repl
->recovery_offset
== MaxSector
1564 && !test_bit(Faulty
, &repl
->flags
)
1565 && !test_and_set_bit(In_sync
, &repl
->flags
)) {
1566 /* replacement has just become active */
1568 !test_and_clear_bit(In_sync
, &rdev
->flags
))
1571 /* Replaced device not technically
1572 * faulty, but we need to be sure
1573 * it gets removed and never re-added
1575 set_bit(Faulty
, &rdev
->flags
);
1576 sysfs_notify_dirent_safe(
1581 && rdev
->recovery_offset
== MaxSector
1582 && !test_bit(Faulty
, &rdev
->flags
)
1583 && !test_and_set_bit(In_sync
, &rdev
->flags
)) {
1585 sysfs_notify_dirent_safe(rdev
->sysfs_state
);
1588 spin_lock_irqsave(&conf
->device_lock
, flags
);
1589 mddev
->degraded
-= count
;
1590 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
1597 static int raid1_add_disk(struct mddev
*mddev
, struct md_rdev
*rdev
)
1599 struct r1conf
*conf
= mddev
->private;
1602 struct raid1_info
*p
;
1604 int last
= conf
->raid_disks
- 1;
1605 struct request_queue
*q
= bdev_get_queue(rdev
->bdev
);
1607 if (mddev
->recovery_disabled
== conf
->recovery_disabled
)
1610 if (rdev
->raid_disk
>= 0)
1611 first
= last
= rdev
->raid_disk
;
1613 if (q
->merge_bvec_fn
) {
1614 set_bit(Unmerged
, &rdev
->flags
);
1615 mddev
->merge_check_needed
= 1;
1618 for (mirror
= first
; mirror
<= last
; mirror
++) {
1619 p
= conf
->mirrors
+mirror
;
1623 disk_stack_limits(mddev
->gendisk
, rdev
->bdev
,
1624 rdev
->data_offset
<< 9);
1626 p
->head_position
= 0;
1627 rdev
->raid_disk
= mirror
;
1629 /* As all devices are equivalent, we don't need a full recovery
1630 * if this was recently any drive of the array
1632 if (rdev
->saved_raid_disk
< 0)
1634 rcu_assign_pointer(p
->rdev
, rdev
);
1637 if (test_bit(WantReplacement
, &p
->rdev
->flags
) &&
1638 p
[conf
->raid_disks
].rdev
== NULL
) {
1639 /* Add this device as a replacement */
1640 clear_bit(In_sync
, &rdev
->flags
);
1641 set_bit(Replacement
, &rdev
->flags
);
1642 rdev
->raid_disk
= mirror
;
1645 rcu_assign_pointer(p
[conf
->raid_disks
].rdev
, rdev
);
1649 if (err
== 0 && test_bit(Unmerged
, &rdev
->flags
)) {
1650 /* Some requests might not have seen this new
1651 * merge_bvec_fn. We must wait for them to complete
1652 * before merging the device fully.
1653 * First we make sure any code which has tested
1654 * our function has submitted the request, then
1655 * we wait for all outstanding requests to complete.
1657 synchronize_sched();
1658 freeze_array(conf
, 0);
1659 unfreeze_array(conf
);
1660 clear_bit(Unmerged
, &rdev
->flags
);
1662 md_integrity_add_rdev(rdev
, mddev
);
1663 if (mddev
->queue
&& blk_queue_discard(bdev_get_queue(rdev
->bdev
)))
1664 queue_flag_set_unlocked(QUEUE_FLAG_DISCARD
, mddev
->queue
);
1669 static int raid1_remove_disk(struct mddev
*mddev
, struct md_rdev
*rdev
)
1671 struct r1conf
*conf
= mddev
->private;
1673 int number
= rdev
->raid_disk
;
1674 struct raid1_info
*p
= conf
->mirrors
+ number
;
1676 if (rdev
!= p
->rdev
)
1677 p
= conf
->mirrors
+ conf
->raid_disks
+ number
;
1680 if (rdev
== p
->rdev
) {
1681 if (test_bit(In_sync
, &rdev
->flags
) ||
1682 atomic_read(&rdev
->nr_pending
)) {
1686 /* Only remove non-faulty devices if recovery
1689 if (!test_bit(Faulty
, &rdev
->flags
) &&
1690 mddev
->recovery_disabled
!= conf
->recovery_disabled
&&
1691 mddev
->degraded
< conf
->raid_disks
) {
1697 if (atomic_read(&rdev
->nr_pending
)) {
1698 /* lost the race, try later */
1702 } else if (conf
->mirrors
[conf
->raid_disks
+ number
].rdev
) {
1703 /* We just removed a device that is being replaced.
1704 * Move down the replacement. We drain all IO before
1705 * doing this to avoid confusion.
1707 struct md_rdev
*repl
=
1708 conf
->mirrors
[conf
->raid_disks
+ number
].rdev
;
1709 freeze_array(conf
, 0);
1710 clear_bit(Replacement
, &repl
->flags
);
1712 conf
->mirrors
[conf
->raid_disks
+ number
].rdev
= NULL
;
1713 unfreeze_array(conf
);
1714 clear_bit(WantReplacement
, &rdev
->flags
);
1716 clear_bit(WantReplacement
, &rdev
->flags
);
1717 err
= md_integrity_register(mddev
);
1726 static void end_sync_read(struct bio
*bio
, int error
)
1728 struct r1bio
*r1_bio
= bio
->bi_private
;
1730 update_head_pos(r1_bio
->read_disk
, r1_bio
);
1733 * we have read a block, now it needs to be re-written,
1734 * or re-read if the read failed.
1735 * We don't do much here, just schedule handling by raid1d
1737 if (test_bit(BIO_UPTODATE
, &bio
->bi_flags
))
1738 set_bit(R1BIO_Uptodate
, &r1_bio
->state
);
1740 if (atomic_dec_and_test(&r1_bio
->remaining
))
1741 reschedule_retry(r1_bio
);
1744 static void end_sync_write(struct bio
*bio
, int error
)
1746 int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
1747 struct r1bio
*r1_bio
= bio
->bi_private
;
1748 struct mddev
*mddev
= r1_bio
->mddev
;
1749 struct r1conf
*conf
= mddev
->private;
1754 mirror
= find_bio_disk(r1_bio
, bio
);
1757 sector_t sync_blocks
= 0;
1758 sector_t s
= r1_bio
->sector
;
1759 long sectors_to_go
= r1_bio
->sectors
;
1760 /* make sure these bits doesn't get cleared. */
1762 bitmap_end_sync(mddev
->bitmap
, s
,
1765 sectors_to_go
-= sync_blocks
;
1766 } while (sectors_to_go
> 0);
1767 set_bit(WriteErrorSeen
,
1768 &conf
->mirrors
[mirror
].rdev
->flags
);
1769 if (!test_and_set_bit(WantReplacement
,
1770 &conf
->mirrors
[mirror
].rdev
->flags
))
1771 set_bit(MD_RECOVERY_NEEDED
, &
1773 set_bit(R1BIO_WriteError
, &r1_bio
->state
);
1774 } else if (is_badblock(conf
->mirrors
[mirror
].rdev
,
1777 &first_bad
, &bad_sectors
) &&
1778 !is_badblock(conf
->mirrors
[r1_bio
->read_disk
].rdev
,
1781 &first_bad
, &bad_sectors
)
1783 set_bit(R1BIO_MadeGood
, &r1_bio
->state
);
1785 if (atomic_dec_and_test(&r1_bio
->remaining
)) {
1786 int s
= r1_bio
->sectors
;
1787 if (test_bit(R1BIO_MadeGood
, &r1_bio
->state
) ||
1788 test_bit(R1BIO_WriteError
, &r1_bio
->state
))
1789 reschedule_retry(r1_bio
);
1792 md_done_sync(mddev
, s
, uptodate
);
1797 static int r1_sync_page_io(struct md_rdev
*rdev
, sector_t sector
,
1798 int sectors
, struct page
*page
, int rw
)
1800 if (sync_page_io(rdev
, sector
, sectors
<< 9, page
, rw
, false))
1804 set_bit(WriteErrorSeen
, &rdev
->flags
);
1805 if (!test_and_set_bit(WantReplacement
,
1807 set_bit(MD_RECOVERY_NEEDED
, &
1808 rdev
->mddev
->recovery
);
1810 /* need to record an error - either for the block or the device */
1811 if (!rdev_set_badblocks(rdev
, sector
, sectors
, 0))
1812 md_error(rdev
->mddev
, rdev
);
1816 static int fix_sync_read_error(struct r1bio
*r1_bio
)
1818 /* Try some synchronous reads of other devices to get
1819 * good data, much like with normal read errors. Only
1820 * read into the pages we already have so we don't
1821 * need to re-issue the read request.
1822 * We don't need to freeze the array, because being in an
1823 * active sync request, there is no normal IO, and
1824 * no overlapping syncs.
1825 * We don't need to check is_badblock() again as we
1826 * made sure that anything with a bad block in range
1827 * will have bi_end_io clear.
1829 struct mddev
*mddev
= r1_bio
->mddev
;
1830 struct r1conf
*conf
= mddev
->private;
1831 struct bio
*bio
= r1_bio
->bios
[r1_bio
->read_disk
];
1832 sector_t sect
= r1_bio
->sector
;
1833 int sectors
= r1_bio
->sectors
;
1838 int d
= r1_bio
->read_disk
;
1840 struct md_rdev
*rdev
;
1843 if (s
> (PAGE_SIZE
>>9))
1846 if (r1_bio
->bios
[d
]->bi_end_io
== end_sync_read
) {
1847 /* No rcu protection needed here devices
1848 * can only be removed when no resync is
1849 * active, and resync is currently active
1851 rdev
= conf
->mirrors
[d
].rdev
;
1852 if (sync_page_io(rdev
, sect
, s
<<9,
1853 bio
->bi_io_vec
[idx
].bv_page
,
1860 if (d
== conf
->raid_disks
* 2)
1862 } while (!success
&& d
!= r1_bio
->read_disk
);
1865 char b
[BDEVNAME_SIZE
];
1867 /* Cannot read from anywhere, this block is lost.
1868 * Record a bad block on each device. If that doesn't
1869 * work just disable and interrupt the recovery.
1870 * Don't fail devices as that won't really help.
1872 printk(KERN_ALERT
"md/raid1:%s: %s: unrecoverable I/O read error"
1873 " for block %llu\n",
1875 bdevname(bio
->bi_bdev
, b
),
1876 (unsigned long long)r1_bio
->sector
);
1877 for (d
= 0; d
< conf
->raid_disks
* 2; d
++) {
1878 rdev
= conf
->mirrors
[d
].rdev
;
1879 if (!rdev
|| test_bit(Faulty
, &rdev
->flags
))
1881 if (!rdev_set_badblocks(rdev
, sect
, s
, 0))
1885 conf
->recovery_disabled
=
1886 mddev
->recovery_disabled
;
1887 set_bit(MD_RECOVERY_INTR
, &mddev
->recovery
);
1888 md_done_sync(mddev
, r1_bio
->sectors
, 0);
1900 /* write it back and re-read */
1901 while (d
!= r1_bio
->read_disk
) {
1903 d
= conf
->raid_disks
* 2;
1905 if (r1_bio
->bios
[d
]->bi_end_io
!= end_sync_read
)
1907 rdev
= conf
->mirrors
[d
].rdev
;
1908 if (r1_sync_page_io(rdev
, sect
, s
,
1909 bio
->bi_io_vec
[idx
].bv_page
,
1911 r1_bio
->bios
[d
]->bi_end_io
= NULL
;
1912 rdev_dec_pending(rdev
, mddev
);
1916 while (d
!= r1_bio
->read_disk
) {
1918 d
= conf
->raid_disks
* 2;
1920 if (r1_bio
->bios
[d
]->bi_end_io
!= end_sync_read
)
1922 rdev
= conf
->mirrors
[d
].rdev
;
1923 if (r1_sync_page_io(rdev
, sect
, s
,
1924 bio
->bi_io_vec
[idx
].bv_page
,
1926 atomic_add(s
, &rdev
->corrected_errors
);
1932 set_bit(R1BIO_Uptodate
, &r1_bio
->state
);
1933 set_bit(BIO_UPTODATE
, &bio
->bi_flags
);
1937 static int process_checks(struct r1bio
*r1_bio
)
1939 /* We have read all readable devices. If we haven't
1940 * got the block, then there is no hope left.
1941 * If we have, then we want to do a comparison
1942 * and skip the write if everything is the same.
1943 * If any blocks failed to read, then we need to
1944 * attempt an over-write
1946 struct mddev
*mddev
= r1_bio
->mddev
;
1947 struct r1conf
*conf
= mddev
->private;
1952 /* Fix variable parts of all bios */
1953 vcnt
= (r1_bio
->sectors
+ PAGE_SIZE
/ 512 - 1) >> (PAGE_SHIFT
- 9);
1954 for (i
= 0; i
< conf
->raid_disks
* 2; i
++) {
1957 struct bio
*b
= r1_bio
->bios
[i
];
1958 if (b
->bi_end_io
!= end_sync_read
)
1960 /* fixup the bio for reuse */
1963 b
->bi_iter
.bi_size
= r1_bio
->sectors
<< 9;
1964 b
->bi_iter
.bi_sector
= r1_bio
->sector
+
1965 conf
->mirrors
[i
].rdev
->data_offset
;
1966 b
->bi_bdev
= conf
->mirrors
[i
].rdev
->bdev
;
1967 b
->bi_end_io
= end_sync_read
;
1968 b
->bi_private
= r1_bio
;
1970 size
= b
->bi_iter
.bi_size
;
1971 for (j
= 0; j
< vcnt
; j
++) {
1973 bi
= &b
->bi_io_vec
[j
];
1975 if (size
> PAGE_SIZE
)
1976 bi
->bv_len
= PAGE_SIZE
;
1982 for (primary
= 0; primary
< conf
->raid_disks
* 2; primary
++)
1983 if (r1_bio
->bios
[primary
]->bi_end_io
== end_sync_read
&&
1984 test_bit(BIO_UPTODATE
, &r1_bio
->bios
[primary
]->bi_flags
)) {
1985 r1_bio
->bios
[primary
]->bi_end_io
= NULL
;
1986 rdev_dec_pending(conf
->mirrors
[primary
].rdev
, mddev
);
1989 r1_bio
->read_disk
= primary
;
1990 for (i
= 0; i
< conf
->raid_disks
* 2; i
++) {
1992 struct bio
*pbio
= r1_bio
->bios
[primary
];
1993 struct bio
*sbio
= r1_bio
->bios
[i
];
1995 if (sbio
->bi_end_io
!= end_sync_read
)
1998 if (test_bit(BIO_UPTODATE
, &sbio
->bi_flags
)) {
1999 for (j
= vcnt
; j
-- ; ) {
2001 p
= pbio
->bi_io_vec
[j
].bv_page
;
2002 s
= sbio
->bi_io_vec
[j
].bv_page
;
2003 if (memcmp(page_address(p
),
2005 sbio
->bi_io_vec
[j
].bv_len
))
2011 atomic64_add(r1_bio
->sectors
, &mddev
->resync_mismatches
);
2012 if (j
< 0 || (test_bit(MD_RECOVERY_CHECK
, &mddev
->recovery
)
2013 && test_bit(BIO_UPTODATE
, &sbio
->bi_flags
))) {
2014 /* No need to write to this device. */
2015 sbio
->bi_end_io
= NULL
;
2016 rdev_dec_pending(conf
->mirrors
[i
].rdev
, mddev
);
2020 bio_copy_data(sbio
, pbio
);
2025 static void sync_request_write(struct mddev
*mddev
, struct r1bio
*r1_bio
)
2027 struct r1conf
*conf
= mddev
->private;
2029 int disks
= conf
->raid_disks
* 2;
2030 struct bio
*bio
, *wbio
;
2032 bio
= r1_bio
->bios
[r1_bio
->read_disk
];
2034 if (!test_bit(R1BIO_Uptodate
, &r1_bio
->state
))
2035 /* ouch - failed to read all of that. */
2036 if (!fix_sync_read_error(r1_bio
))
2039 if (test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
))
2040 if (process_checks(r1_bio
) < 0)
2045 atomic_set(&r1_bio
->remaining
, 1);
2046 for (i
= 0; i
< disks
; i
++) {
2047 wbio
= r1_bio
->bios
[i
];
2048 if (wbio
->bi_end_io
== NULL
||
2049 (wbio
->bi_end_io
== end_sync_read
&&
2050 (i
== r1_bio
->read_disk
||
2051 !test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
))))
2054 wbio
->bi_rw
= WRITE
;
2055 wbio
->bi_end_io
= end_sync_write
;
2056 atomic_inc(&r1_bio
->remaining
);
2057 md_sync_acct(conf
->mirrors
[i
].rdev
->bdev
, bio_sectors(wbio
));
2059 generic_make_request(wbio
);
2062 if (atomic_dec_and_test(&r1_bio
->remaining
)) {
2063 /* if we're here, all write(s) have completed, so clean up */
2064 int s
= r1_bio
->sectors
;
2065 if (test_bit(R1BIO_MadeGood
, &r1_bio
->state
) ||
2066 test_bit(R1BIO_WriteError
, &r1_bio
->state
))
2067 reschedule_retry(r1_bio
);
2070 md_done_sync(mddev
, s
, 1);
2076 * This is a kernel thread which:
2078 * 1. Retries failed read operations on working mirrors.
2079 * 2. Updates the raid superblock when problems encounter.
2080 * 3. Performs writes following reads for array synchronising.
2083 static void fix_read_error(struct r1conf
*conf
, int read_disk
,
2084 sector_t sect
, int sectors
)
2086 struct mddev
*mddev
= conf
->mddev
;
2092 struct md_rdev
*rdev
;
2094 if (s
> (PAGE_SIZE
>>9))
2098 /* Note: no rcu protection needed here
2099 * as this is synchronous in the raid1d thread
2100 * which is the thread that might remove
2101 * a device. If raid1d ever becomes multi-threaded....
2106 rdev
= conf
->mirrors
[d
].rdev
;
2108 (test_bit(In_sync
, &rdev
->flags
) ||
2109 (!test_bit(Faulty
, &rdev
->flags
) &&
2110 rdev
->recovery_offset
>= sect
+ s
)) &&
2111 is_badblock(rdev
, sect
, s
,
2112 &first_bad
, &bad_sectors
) == 0 &&
2113 sync_page_io(rdev
, sect
, s
<<9,
2114 conf
->tmppage
, READ
, false))
2118 if (d
== conf
->raid_disks
* 2)
2121 } while (!success
&& d
!= read_disk
);
2124 /* Cannot read from anywhere - mark it bad */
2125 struct md_rdev
*rdev
= conf
->mirrors
[read_disk
].rdev
;
2126 if (!rdev_set_badblocks(rdev
, sect
, s
, 0))
2127 md_error(mddev
, rdev
);
2130 /* write it back and re-read */
2132 while (d
!= read_disk
) {
2134 d
= conf
->raid_disks
* 2;
2136 rdev
= conf
->mirrors
[d
].rdev
;
2138 test_bit(In_sync
, &rdev
->flags
))
2139 r1_sync_page_io(rdev
, sect
, s
,
2140 conf
->tmppage
, WRITE
);
2143 while (d
!= read_disk
) {
2144 char b
[BDEVNAME_SIZE
];
2146 d
= conf
->raid_disks
* 2;
2148 rdev
= conf
->mirrors
[d
].rdev
;
2150 test_bit(In_sync
, &rdev
->flags
)) {
2151 if (r1_sync_page_io(rdev
, sect
, s
,
2152 conf
->tmppage
, READ
)) {
2153 atomic_add(s
, &rdev
->corrected_errors
);
2155 "md/raid1:%s: read error corrected "
2156 "(%d sectors at %llu on %s)\n",
2158 (unsigned long long)(sect
+
2160 bdevname(rdev
->bdev
, b
));
2169 static int narrow_write_error(struct r1bio
*r1_bio
, int i
)
2171 struct mddev
*mddev
= r1_bio
->mddev
;
2172 struct r1conf
*conf
= mddev
->private;
2173 struct md_rdev
*rdev
= conf
->mirrors
[i
].rdev
;
2175 /* bio has the data to be written to device 'i' where
2176 * we just recently had a write error.
2177 * We repeatedly clone the bio and trim down to one block,
2178 * then try the write. Where the write fails we record
2180 * It is conceivable that the bio doesn't exactly align with
2181 * blocks. We must handle this somehow.
2183 * We currently own a reference on the rdev.
2189 int sect_to_write
= r1_bio
->sectors
;
2192 if (rdev
->badblocks
.shift
< 0)
2195 block_sectors
= 1 << rdev
->badblocks
.shift
;
2196 sector
= r1_bio
->sector
;
2197 sectors
= ((sector
+ block_sectors
)
2198 & ~(sector_t
)(block_sectors
- 1))
2201 while (sect_to_write
) {
2203 if (sectors
> sect_to_write
)
2204 sectors
= sect_to_write
;
2205 /* Write at 'sector' for 'sectors'*/
2207 if (test_bit(R1BIO_BehindIO
, &r1_bio
->state
)) {
2208 unsigned vcnt
= r1_bio
->behind_page_count
;
2209 struct bio_vec
*vec
= r1_bio
->behind_bvecs
;
2211 while (!vec
->bv_page
) {
2216 wbio
= bio_alloc_mddev(GFP_NOIO
, vcnt
, mddev
);
2217 memcpy(wbio
->bi_io_vec
, vec
, vcnt
* sizeof(struct bio_vec
));
2219 wbio
->bi_vcnt
= vcnt
;
2221 wbio
= bio_clone_mddev(r1_bio
->master_bio
, GFP_NOIO
, mddev
);
2224 wbio
->bi_rw
= WRITE
;
2225 wbio
->bi_iter
.bi_sector
= r1_bio
->sector
;
2226 wbio
->bi_iter
.bi_size
= r1_bio
->sectors
<< 9;
2228 bio_trim(wbio
, sector
- r1_bio
->sector
, sectors
);
2229 wbio
->bi_iter
.bi_sector
+= rdev
->data_offset
;
2230 wbio
->bi_bdev
= rdev
->bdev
;
2231 if (submit_bio_wait(WRITE
, wbio
) == 0)
2233 ok
= rdev_set_badblocks(rdev
, sector
,
2238 sect_to_write
-= sectors
;
2240 sectors
= block_sectors
;
2245 static void handle_sync_write_finished(struct r1conf
*conf
, struct r1bio
*r1_bio
)
2248 int s
= r1_bio
->sectors
;
2249 for (m
= 0; m
< conf
->raid_disks
* 2 ; m
++) {
2250 struct md_rdev
*rdev
= conf
->mirrors
[m
].rdev
;
2251 struct bio
*bio
= r1_bio
->bios
[m
];
2252 if (bio
->bi_end_io
== NULL
)
2254 if (test_bit(BIO_UPTODATE
, &bio
->bi_flags
) &&
2255 test_bit(R1BIO_MadeGood
, &r1_bio
->state
)) {
2256 rdev_clear_badblocks(rdev
, r1_bio
->sector
, s
, 0);
2258 if (!test_bit(BIO_UPTODATE
, &bio
->bi_flags
) &&
2259 test_bit(R1BIO_WriteError
, &r1_bio
->state
)) {
2260 if (!rdev_set_badblocks(rdev
, r1_bio
->sector
, s
, 0))
2261 md_error(conf
->mddev
, rdev
);
2265 md_done_sync(conf
->mddev
, s
, 1);
2268 static void handle_write_finished(struct r1conf
*conf
, struct r1bio
*r1_bio
)
2271 for (m
= 0; m
< conf
->raid_disks
* 2 ; m
++)
2272 if (r1_bio
->bios
[m
] == IO_MADE_GOOD
) {
2273 struct md_rdev
*rdev
= conf
->mirrors
[m
].rdev
;
2274 rdev_clear_badblocks(rdev
,
2276 r1_bio
->sectors
, 0);
2277 rdev_dec_pending(rdev
, conf
->mddev
);
2278 } else if (r1_bio
->bios
[m
] != NULL
) {
2279 /* This drive got a write error. We need to
2280 * narrow down and record precise write
2283 if (!narrow_write_error(r1_bio
, m
)) {
2284 md_error(conf
->mddev
,
2285 conf
->mirrors
[m
].rdev
);
2286 /* an I/O failed, we can't clear the bitmap */
2287 set_bit(R1BIO_Degraded
, &r1_bio
->state
);
2289 rdev_dec_pending(conf
->mirrors
[m
].rdev
,
2292 if (test_bit(R1BIO_WriteError
, &r1_bio
->state
))
2293 close_write(r1_bio
);
2294 raid_end_bio_io(r1_bio
);
2297 static void handle_read_error(struct r1conf
*conf
, struct r1bio
*r1_bio
)
2301 struct mddev
*mddev
= conf
->mddev
;
2303 char b
[BDEVNAME_SIZE
];
2304 struct md_rdev
*rdev
;
2306 clear_bit(R1BIO_ReadError
, &r1_bio
->state
);
2307 /* we got a read error. Maybe the drive is bad. Maybe just
2308 * the block and we can fix it.
2309 * We freeze all other IO, and try reading the block from
2310 * other devices. When we find one, we re-write
2311 * and check it that fixes the read error.
2312 * This is all done synchronously while the array is
2315 if (mddev
->ro
== 0) {
2316 freeze_array(conf
, 1);
2317 fix_read_error(conf
, r1_bio
->read_disk
,
2318 r1_bio
->sector
, r1_bio
->sectors
);
2319 unfreeze_array(conf
);
2321 md_error(mddev
, conf
->mirrors
[r1_bio
->read_disk
].rdev
);
2322 rdev_dec_pending(conf
->mirrors
[r1_bio
->read_disk
].rdev
, conf
->mddev
);
2324 bio
= r1_bio
->bios
[r1_bio
->read_disk
];
2325 bdevname(bio
->bi_bdev
, b
);
2327 disk
= read_balance(conf
, r1_bio
, &max_sectors
);
2329 printk(KERN_ALERT
"md/raid1:%s: %s: unrecoverable I/O"
2330 " read error for block %llu\n",
2331 mdname(mddev
), b
, (unsigned long long)r1_bio
->sector
);
2332 raid_end_bio_io(r1_bio
);
2334 const unsigned long do_sync
2335 = r1_bio
->master_bio
->bi_rw
& REQ_SYNC
;
2337 r1_bio
->bios
[r1_bio
->read_disk
] =
2338 mddev
->ro
? IO_BLOCKED
: NULL
;
2341 r1_bio
->read_disk
= disk
;
2342 bio
= bio_clone_mddev(r1_bio
->master_bio
, GFP_NOIO
, mddev
);
2343 bio_trim(bio
, r1_bio
->sector
- bio
->bi_iter
.bi_sector
,
2345 r1_bio
->bios
[r1_bio
->read_disk
] = bio
;
2346 rdev
= conf
->mirrors
[disk
].rdev
;
2347 printk_ratelimited(KERN_ERR
2348 "md/raid1:%s: redirecting sector %llu"
2349 " to other mirror: %s\n",
2351 (unsigned long long)r1_bio
->sector
,
2352 bdevname(rdev
->bdev
, b
));
2353 bio
->bi_iter
.bi_sector
= r1_bio
->sector
+ rdev
->data_offset
;
2354 bio
->bi_bdev
= rdev
->bdev
;
2355 bio
->bi_end_io
= raid1_end_read_request
;
2356 bio
->bi_rw
= READ
| do_sync
;
2357 bio
->bi_private
= r1_bio
;
2358 if (max_sectors
< r1_bio
->sectors
) {
2359 /* Drat - have to split this up more */
2360 struct bio
*mbio
= r1_bio
->master_bio
;
2361 int sectors_handled
= (r1_bio
->sector
+ max_sectors
2362 - mbio
->bi_iter
.bi_sector
);
2363 r1_bio
->sectors
= max_sectors
;
2364 spin_lock_irq(&conf
->device_lock
);
2365 if (mbio
->bi_phys_segments
== 0)
2366 mbio
->bi_phys_segments
= 2;
2368 mbio
->bi_phys_segments
++;
2369 spin_unlock_irq(&conf
->device_lock
);
2370 generic_make_request(bio
);
2373 r1_bio
= mempool_alloc(conf
->r1bio_pool
, GFP_NOIO
);
2375 r1_bio
->master_bio
= mbio
;
2376 r1_bio
->sectors
= bio_sectors(mbio
) - sectors_handled
;
2378 set_bit(R1BIO_ReadError
, &r1_bio
->state
);
2379 r1_bio
->mddev
= mddev
;
2380 r1_bio
->sector
= mbio
->bi_iter
.bi_sector
+
2385 generic_make_request(bio
);
2389 static void raid1d(struct md_thread
*thread
)
2391 struct mddev
*mddev
= thread
->mddev
;
2392 struct r1bio
*r1_bio
;
2393 unsigned long flags
;
2394 struct r1conf
*conf
= mddev
->private;
2395 struct list_head
*head
= &conf
->retry_list
;
2396 struct blk_plug plug
;
2398 md_check_recovery(mddev
);
2400 blk_start_plug(&plug
);
2403 flush_pending_writes(conf
);
2405 spin_lock_irqsave(&conf
->device_lock
, flags
);
2406 if (list_empty(head
)) {
2407 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
2410 r1_bio
= list_entry(head
->prev
, struct r1bio
, retry_list
);
2411 list_del(head
->prev
);
2413 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
2415 mddev
= r1_bio
->mddev
;
2416 conf
= mddev
->private;
2417 if (test_bit(R1BIO_IsSync
, &r1_bio
->state
)) {
2418 if (test_bit(R1BIO_MadeGood
, &r1_bio
->state
) ||
2419 test_bit(R1BIO_WriteError
, &r1_bio
->state
))
2420 handle_sync_write_finished(conf
, r1_bio
);
2422 sync_request_write(mddev
, r1_bio
);
2423 } else if (test_bit(R1BIO_MadeGood
, &r1_bio
->state
) ||
2424 test_bit(R1BIO_WriteError
, &r1_bio
->state
))
2425 handle_write_finished(conf
, r1_bio
);
2426 else if (test_bit(R1BIO_ReadError
, &r1_bio
->state
))
2427 handle_read_error(conf
, r1_bio
);
2429 /* just a partial read to be scheduled from separate
2432 generic_make_request(r1_bio
->bios
[r1_bio
->read_disk
]);
2435 if (mddev
->flags
& ~(1<<MD_CHANGE_PENDING
))
2436 md_check_recovery(mddev
);
2438 blk_finish_plug(&plug
);
2442 static int init_resync(struct r1conf
*conf
)
2446 buffs
= RESYNC_WINDOW
/ RESYNC_BLOCK_SIZE
;
2447 BUG_ON(conf
->r1buf_pool
);
2448 conf
->r1buf_pool
= mempool_create(buffs
, r1buf_pool_alloc
, r1buf_pool_free
,
2450 if (!conf
->r1buf_pool
)
2452 conf
->next_resync
= 0;
2457 * perform a "sync" on one "block"
2459 * We need to make sure that no normal I/O request - particularly write
2460 * requests - conflict with active sync requests.
2462 * This is achieved by tracking pending requests and a 'barrier' concept
2463 * that can be installed to exclude normal IO requests.
2466 static sector_t
sync_request(struct mddev
*mddev
, sector_t sector_nr
, int *skipped
, int go_faster
)
2468 struct r1conf
*conf
= mddev
->private;
2469 struct r1bio
*r1_bio
;
2471 sector_t max_sector
, nr_sectors
;
2475 int write_targets
= 0, read_targets
= 0;
2476 sector_t sync_blocks
;
2477 int still_degraded
= 0;
2478 int good_sectors
= RESYNC_SECTORS
;
2479 int min_bad
= 0; /* number of sectors that are bad in all devices */
2481 if (!conf
->r1buf_pool
)
2482 if (init_resync(conf
))
2485 max_sector
= mddev
->dev_sectors
;
2486 if (sector_nr
>= max_sector
) {
2487 /* If we aborted, we need to abort the
2488 * sync on the 'current' bitmap chunk (there will
2489 * only be one in raid1 resync.
2490 * We can find the current addess in mddev->curr_resync
2492 if (mddev
->curr_resync
< max_sector
) /* aborted */
2493 bitmap_end_sync(mddev
->bitmap
, mddev
->curr_resync
,
2495 else /* completed sync */
2498 bitmap_close_sync(mddev
->bitmap
);
2503 if (mddev
->bitmap
== NULL
&&
2504 mddev
->recovery_cp
== MaxSector
&&
2505 !test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
) &&
2506 conf
->fullsync
== 0) {
2508 return max_sector
- sector_nr
;
2510 /* before building a request, check if we can skip these blocks..
2511 * This call the bitmap_start_sync doesn't actually record anything
2513 if (!bitmap_start_sync(mddev
->bitmap
, sector_nr
, &sync_blocks
, 1) &&
2514 !conf
->fullsync
&& !test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
)) {
2515 /* We can skip this block, and probably several more */
2520 * If there is non-resync activity waiting for a turn,
2521 * and resync is going fast enough,
2522 * then let it though before starting on this new sync request.
2524 if (!go_faster
&& conf
->nr_waiting
)
2525 msleep_interruptible(1000);
2527 bitmap_cond_end_sync(mddev
->bitmap
, sector_nr
);
2528 r1_bio
= mempool_alloc(conf
->r1buf_pool
, GFP_NOIO
);
2529 raise_barrier(conf
);
2531 conf
->next_resync
= sector_nr
;
2535 * If we get a correctably read error during resync or recovery,
2536 * we might want to read from a different device. So we
2537 * flag all drives that could conceivably be read from for READ,
2538 * and any others (which will be non-In_sync devices) for WRITE.
2539 * If a read fails, we try reading from something else for which READ
2543 r1_bio
->mddev
= mddev
;
2544 r1_bio
->sector
= sector_nr
;
2546 set_bit(R1BIO_IsSync
, &r1_bio
->state
);
2548 for (i
= 0; i
< conf
->raid_disks
* 2; i
++) {
2549 struct md_rdev
*rdev
;
2550 bio
= r1_bio
->bios
[i
];
2553 rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
2555 test_bit(Faulty
, &rdev
->flags
)) {
2556 if (i
< conf
->raid_disks
)
2558 } else if (!test_bit(In_sync
, &rdev
->flags
)) {
2560 bio
->bi_end_io
= end_sync_write
;
2563 /* may need to read from here */
2564 sector_t first_bad
= MaxSector
;
2567 if (is_badblock(rdev
, sector_nr
, good_sectors
,
2568 &first_bad
, &bad_sectors
)) {
2569 if (first_bad
> sector_nr
)
2570 good_sectors
= first_bad
- sector_nr
;
2572 bad_sectors
-= (sector_nr
- first_bad
);
2574 min_bad
> bad_sectors
)
2575 min_bad
= bad_sectors
;
2578 if (sector_nr
< first_bad
) {
2579 if (test_bit(WriteMostly
, &rdev
->flags
)) {
2587 bio
->bi_end_io
= end_sync_read
;
2589 } else if (!test_bit(WriteErrorSeen
, &rdev
->flags
) &&
2590 test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
) &&
2591 !test_bit(MD_RECOVERY_CHECK
, &mddev
->recovery
)) {
2593 * The device is suitable for reading (InSync),
2594 * but has bad block(s) here. Let's try to correct them,
2595 * if we are doing resync or repair. Otherwise, leave
2596 * this device alone for this sync request.
2599 bio
->bi_end_io
= end_sync_write
;
2603 if (bio
->bi_end_io
) {
2604 atomic_inc(&rdev
->nr_pending
);
2605 bio
->bi_iter
.bi_sector
= sector_nr
+ rdev
->data_offset
;
2606 bio
->bi_bdev
= rdev
->bdev
;
2607 bio
->bi_private
= r1_bio
;
2613 r1_bio
->read_disk
= disk
;
2615 if (read_targets
== 0 && min_bad
> 0) {
2616 /* These sectors are bad on all InSync devices, so we
2617 * need to mark them bad on all write targets
2620 for (i
= 0 ; i
< conf
->raid_disks
* 2 ; i
++)
2621 if (r1_bio
->bios
[i
]->bi_end_io
== end_sync_write
) {
2622 struct md_rdev
*rdev
= conf
->mirrors
[i
].rdev
;
2623 ok
= rdev_set_badblocks(rdev
, sector_nr
,
2627 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
2632 /* Cannot record the badblocks, so need to
2634 * If there are multiple read targets, could just
2635 * fail the really bad ones ???
2637 conf
->recovery_disabled
= mddev
->recovery_disabled
;
2638 set_bit(MD_RECOVERY_INTR
, &mddev
->recovery
);
2644 if (min_bad
> 0 && min_bad
< good_sectors
) {
2645 /* only resync enough to reach the next bad->good
2647 good_sectors
= min_bad
;
2650 if (test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
) && read_targets
> 0)
2651 /* extra read targets are also write targets */
2652 write_targets
+= read_targets
-1;
2654 if (write_targets
== 0 || read_targets
== 0) {
2655 /* There is nowhere to write, so all non-sync
2656 * drives must be failed - so we are finished
2660 max_sector
= sector_nr
+ min_bad
;
2661 rv
= max_sector
- sector_nr
;
2667 if (max_sector
> mddev
->resync_max
)
2668 max_sector
= mddev
->resync_max
; /* Don't do IO beyond here */
2669 if (max_sector
> sector_nr
+ good_sectors
)
2670 max_sector
= sector_nr
+ good_sectors
;
2675 int len
= PAGE_SIZE
;
2676 if (sector_nr
+ (len
>>9) > max_sector
)
2677 len
= (max_sector
- sector_nr
) << 9;
2680 if (sync_blocks
== 0) {
2681 if (!bitmap_start_sync(mddev
->bitmap
, sector_nr
,
2682 &sync_blocks
, still_degraded
) &&
2684 !test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
))
2686 BUG_ON(sync_blocks
< (PAGE_SIZE
>>9));
2687 if ((len
>> 9) > sync_blocks
)
2688 len
= sync_blocks
<<9;
2691 for (i
= 0 ; i
< conf
->raid_disks
* 2; i
++) {
2692 bio
= r1_bio
->bios
[i
];
2693 if (bio
->bi_end_io
) {
2694 page
= bio
->bi_io_vec
[bio
->bi_vcnt
].bv_page
;
2695 if (bio_add_page(bio
, page
, len
, 0) == 0) {
2697 bio
->bi_io_vec
[bio
->bi_vcnt
].bv_page
= page
;
2700 bio
= r1_bio
->bios
[i
];
2701 if (bio
->bi_end_io
==NULL
)
2703 /* remove last page from this bio */
2705 bio
->bi_iter
.bi_size
-= len
;
2706 bio
->bi_flags
&= ~(1<< BIO_SEG_VALID
);
2712 nr_sectors
+= len
>>9;
2713 sector_nr
+= len
>>9;
2714 sync_blocks
-= (len
>>9);
2715 } while (r1_bio
->bios
[disk
]->bi_vcnt
< RESYNC_PAGES
);
2717 r1_bio
->sectors
= nr_sectors
;
2719 /* For a user-requested sync, we read all readable devices and do a
2722 if (test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
)) {
2723 atomic_set(&r1_bio
->remaining
, read_targets
);
2724 for (i
= 0; i
< conf
->raid_disks
* 2 && read_targets
; i
++) {
2725 bio
= r1_bio
->bios
[i
];
2726 if (bio
->bi_end_io
== end_sync_read
) {
2728 md_sync_acct(bio
->bi_bdev
, nr_sectors
);
2729 generic_make_request(bio
);
2733 atomic_set(&r1_bio
->remaining
, 1);
2734 bio
= r1_bio
->bios
[r1_bio
->read_disk
];
2735 md_sync_acct(bio
->bi_bdev
, nr_sectors
);
2736 generic_make_request(bio
);
2742 static sector_t
raid1_size(struct mddev
*mddev
, sector_t sectors
, int raid_disks
)
2747 return mddev
->dev_sectors
;
2750 static struct r1conf
*setup_conf(struct mddev
*mddev
)
2752 struct r1conf
*conf
;
2754 struct raid1_info
*disk
;
2755 struct md_rdev
*rdev
;
2758 conf
= kzalloc(sizeof(struct r1conf
), GFP_KERNEL
);
2762 conf
->mirrors
= kzalloc(sizeof(struct raid1_info
)
2763 * mddev
->raid_disks
* 2,
2768 conf
->tmppage
= alloc_page(GFP_KERNEL
);
2772 conf
->poolinfo
= kzalloc(sizeof(*conf
->poolinfo
), GFP_KERNEL
);
2773 if (!conf
->poolinfo
)
2775 conf
->poolinfo
->raid_disks
= mddev
->raid_disks
* 2;
2776 conf
->r1bio_pool
= mempool_create(NR_RAID1_BIOS
, r1bio_pool_alloc
,
2779 if (!conf
->r1bio_pool
)
2782 conf
->poolinfo
->mddev
= mddev
;
2785 spin_lock_init(&conf
->device_lock
);
2786 rdev_for_each(rdev
, mddev
) {
2787 struct request_queue
*q
;
2788 int disk_idx
= rdev
->raid_disk
;
2789 if (disk_idx
>= mddev
->raid_disks
2792 if (test_bit(Replacement
, &rdev
->flags
))
2793 disk
= conf
->mirrors
+ mddev
->raid_disks
+ disk_idx
;
2795 disk
= conf
->mirrors
+ disk_idx
;
2800 q
= bdev_get_queue(rdev
->bdev
);
2801 if (q
->merge_bvec_fn
)
2802 mddev
->merge_check_needed
= 1;
2804 disk
->head_position
= 0;
2805 disk
->seq_start
= MaxSector
;
2807 conf
->raid_disks
= mddev
->raid_disks
;
2808 conf
->mddev
= mddev
;
2809 INIT_LIST_HEAD(&conf
->retry_list
);
2811 spin_lock_init(&conf
->resync_lock
);
2812 init_waitqueue_head(&conf
->wait_barrier
);
2814 bio_list_init(&conf
->pending_bio_list
);
2815 conf
->pending_count
= 0;
2816 conf
->recovery_disabled
= mddev
->recovery_disabled
- 1;
2818 conf
->start_next_window
= MaxSector
;
2819 conf
->current_window_requests
= conf
->next_window_requests
= 0;
2822 for (i
= 0; i
< conf
->raid_disks
* 2; i
++) {
2824 disk
= conf
->mirrors
+ i
;
2826 if (i
< conf
->raid_disks
&&
2827 disk
[conf
->raid_disks
].rdev
) {
2828 /* This slot has a replacement. */
2830 /* No original, just make the replacement
2831 * a recovering spare
2834 disk
[conf
->raid_disks
].rdev
;
2835 disk
[conf
->raid_disks
].rdev
= NULL
;
2836 } else if (!test_bit(In_sync
, &disk
->rdev
->flags
))
2837 /* Original is not in_sync - bad */
2842 !test_bit(In_sync
, &disk
->rdev
->flags
)) {
2843 disk
->head_position
= 0;
2845 (disk
->rdev
->saved_raid_disk
< 0))
2851 conf
->thread
= md_register_thread(raid1d
, mddev
, "raid1");
2852 if (!conf
->thread
) {
2854 "md/raid1:%s: couldn't allocate thread\n",
2863 if (conf
->r1bio_pool
)
2864 mempool_destroy(conf
->r1bio_pool
);
2865 kfree(conf
->mirrors
);
2866 safe_put_page(conf
->tmppage
);
2867 kfree(conf
->poolinfo
);
2870 return ERR_PTR(err
);
2873 static int stop(struct mddev
*mddev
);
2874 static int run(struct mddev
*mddev
)
2876 struct r1conf
*conf
;
2878 struct md_rdev
*rdev
;
2880 bool discard_supported
= false;
2882 if (mddev
->level
!= 1) {
2883 printk(KERN_ERR
"md/raid1:%s: raid level not set to mirroring (%d)\n",
2884 mdname(mddev
), mddev
->level
);
2887 if (mddev
->reshape_position
!= MaxSector
) {
2888 printk(KERN_ERR
"md/raid1:%s: reshape_position set but not supported\n",
2893 * copy the already verified devices into our private RAID1
2894 * bookkeeping area. [whatever we allocate in run(),
2895 * should be freed in stop()]
2897 if (mddev
->private == NULL
)
2898 conf
= setup_conf(mddev
);
2900 conf
= mddev
->private;
2903 return PTR_ERR(conf
);
2906 blk_queue_max_write_same_sectors(mddev
->queue
, 0);
2908 rdev_for_each(rdev
, mddev
) {
2909 if (!mddev
->gendisk
)
2911 disk_stack_limits(mddev
->gendisk
, rdev
->bdev
,
2912 rdev
->data_offset
<< 9);
2913 if (blk_queue_discard(bdev_get_queue(rdev
->bdev
)))
2914 discard_supported
= true;
2917 mddev
->degraded
= 0;
2918 for (i
=0; i
< conf
->raid_disks
; i
++)
2919 if (conf
->mirrors
[i
].rdev
== NULL
||
2920 !test_bit(In_sync
, &conf
->mirrors
[i
].rdev
->flags
) ||
2921 test_bit(Faulty
, &conf
->mirrors
[i
].rdev
->flags
))
2924 if (conf
->raid_disks
- mddev
->degraded
== 1)
2925 mddev
->recovery_cp
= MaxSector
;
2927 if (mddev
->recovery_cp
!= MaxSector
)
2928 printk(KERN_NOTICE
"md/raid1:%s: not clean"
2929 " -- starting background reconstruction\n",
2932 "md/raid1:%s: active with %d out of %d mirrors\n",
2933 mdname(mddev
), mddev
->raid_disks
- mddev
->degraded
,
2937 * Ok, everything is just fine now
2939 mddev
->thread
= conf
->thread
;
2940 conf
->thread
= NULL
;
2941 mddev
->private = conf
;
2943 md_set_array_sectors(mddev
, raid1_size(mddev
, 0, 0));
2946 mddev
->queue
->backing_dev_info
.congested_fn
= raid1_congested
;
2947 mddev
->queue
->backing_dev_info
.congested_data
= mddev
;
2948 blk_queue_merge_bvec(mddev
->queue
, raid1_mergeable_bvec
);
2950 if (discard_supported
)
2951 queue_flag_set_unlocked(QUEUE_FLAG_DISCARD
,
2954 queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD
,
2958 ret
= md_integrity_register(mddev
);
2964 static int stop(struct mddev
*mddev
)
2966 struct r1conf
*conf
= mddev
->private;
2967 struct bitmap
*bitmap
= mddev
->bitmap
;
2969 /* wait for behind writes to complete */
2970 if (bitmap
&& atomic_read(&bitmap
->behind_writes
) > 0) {
2971 printk(KERN_INFO
"md/raid1:%s: behind writes in progress - waiting to stop.\n",
2973 /* need to kick something here to make sure I/O goes? */
2974 wait_event(bitmap
->behind_wait
,
2975 atomic_read(&bitmap
->behind_writes
) == 0);
2978 freeze_array(conf
, 0);
2979 unfreeze_array(conf
);
2981 md_unregister_thread(&mddev
->thread
);
2982 if (conf
->r1bio_pool
)
2983 mempool_destroy(conf
->r1bio_pool
);
2984 kfree(conf
->mirrors
);
2985 safe_put_page(conf
->tmppage
);
2986 kfree(conf
->poolinfo
);
2988 mddev
->private = NULL
;
2992 static int raid1_resize(struct mddev
*mddev
, sector_t sectors
)
2994 /* no resync is happening, and there is enough space
2995 * on all devices, so we can resize.
2996 * We need to make sure resync covers any new space.
2997 * If the array is shrinking we should possibly wait until
2998 * any io in the removed space completes, but it hardly seems
3001 sector_t newsize
= raid1_size(mddev
, sectors
, 0);
3002 if (mddev
->external_size
&&
3003 mddev
->array_sectors
> newsize
)
3005 if (mddev
->bitmap
) {
3006 int ret
= bitmap_resize(mddev
->bitmap
, newsize
, 0, 0);
3010 md_set_array_sectors(mddev
, newsize
);
3011 set_capacity(mddev
->gendisk
, mddev
->array_sectors
);
3012 revalidate_disk(mddev
->gendisk
);
3013 if (sectors
> mddev
->dev_sectors
&&
3014 mddev
->recovery_cp
> mddev
->dev_sectors
) {
3015 mddev
->recovery_cp
= mddev
->dev_sectors
;
3016 set_bit(MD_RECOVERY_NEEDED
, &mddev
->recovery
);
3018 mddev
->dev_sectors
= sectors
;
3019 mddev
->resync_max_sectors
= sectors
;
3023 static int raid1_reshape(struct mddev
*mddev
)
3026 * 1/ resize the r1bio_pool
3027 * 2/ resize conf->mirrors
3029 * We allocate a new r1bio_pool if we can.
3030 * Then raise a device barrier and wait until all IO stops.
3031 * Then resize conf->mirrors and swap in the new r1bio pool.
3033 * At the same time, we "pack" the devices so that all the missing
3034 * devices have the higher raid_disk numbers.
3036 mempool_t
*newpool
, *oldpool
;
3037 struct pool_info
*newpoolinfo
;
3038 struct raid1_info
*newmirrors
;
3039 struct r1conf
*conf
= mddev
->private;
3040 int cnt
, raid_disks
;
3041 unsigned long flags
;
3044 /* Cannot change chunk_size, layout, or level */
3045 if (mddev
->chunk_sectors
!= mddev
->new_chunk_sectors
||
3046 mddev
->layout
!= mddev
->new_layout
||
3047 mddev
->level
!= mddev
->new_level
) {
3048 mddev
->new_chunk_sectors
= mddev
->chunk_sectors
;
3049 mddev
->new_layout
= mddev
->layout
;
3050 mddev
->new_level
= mddev
->level
;
3054 err
= md_allow_write(mddev
);
3058 raid_disks
= mddev
->raid_disks
+ mddev
->delta_disks
;
3060 if (raid_disks
< conf
->raid_disks
) {
3062 for (d
= 0; d
< conf
->raid_disks
; d
++)
3063 if (conf
->mirrors
[d
].rdev
)
3065 if (cnt
> raid_disks
)
3069 newpoolinfo
= kmalloc(sizeof(*newpoolinfo
), GFP_KERNEL
);
3072 newpoolinfo
->mddev
= mddev
;
3073 newpoolinfo
->raid_disks
= raid_disks
* 2;
3075 newpool
= mempool_create(NR_RAID1_BIOS
, r1bio_pool_alloc
,
3076 r1bio_pool_free
, newpoolinfo
);
3081 newmirrors
= kzalloc(sizeof(struct raid1_info
) * raid_disks
* 2,
3085 mempool_destroy(newpool
);
3089 freeze_array(conf
, 0);
3091 /* ok, everything is stopped */
3092 oldpool
= conf
->r1bio_pool
;
3093 conf
->r1bio_pool
= newpool
;
3095 for (d
= d2
= 0; d
< conf
->raid_disks
; d
++) {
3096 struct md_rdev
*rdev
= conf
->mirrors
[d
].rdev
;
3097 if (rdev
&& rdev
->raid_disk
!= d2
) {
3098 sysfs_unlink_rdev(mddev
, rdev
);
3099 rdev
->raid_disk
= d2
;
3100 sysfs_unlink_rdev(mddev
, rdev
);
3101 if (sysfs_link_rdev(mddev
, rdev
))
3103 "md/raid1:%s: cannot register rd%d\n",
3104 mdname(mddev
), rdev
->raid_disk
);
3107 newmirrors
[d2
++].rdev
= rdev
;
3109 kfree(conf
->mirrors
);
3110 conf
->mirrors
= newmirrors
;
3111 kfree(conf
->poolinfo
);
3112 conf
->poolinfo
= newpoolinfo
;
3114 spin_lock_irqsave(&conf
->device_lock
, flags
);
3115 mddev
->degraded
+= (raid_disks
- conf
->raid_disks
);
3116 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
3117 conf
->raid_disks
= mddev
->raid_disks
= raid_disks
;
3118 mddev
->delta_disks
= 0;
3120 unfreeze_array(conf
);
3122 set_bit(MD_RECOVERY_NEEDED
, &mddev
->recovery
);
3123 md_wakeup_thread(mddev
->thread
);
3125 mempool_destroy(oldpool
);
3129 static void raid1_quiesce(struct mddev
*mddev
, int state
)
3131 struct r1conf
*conf
= mddev
->private;
3134 case 2: /* wake for suspend */
3135 wake_up(&conf
->wait_barrier
);
3138 freeze_array(conf
, 0);
3141 unfreeze_array(conf
);
3146 static void *raid1_takeover(struct mddev
*mddev
)
3148 /* raid1 can take over:
3149 * raid5 with 2 devices, any layout or chunk size
3151 if (mddev
->level
== 5 && mddev
->raid_disks
== 2) {
3152 struct r1conf
*conf
;
3153 mddev
->new_level
= 1;
3154 mddev
->new_layout
= 0;
3155 mddev
->new_chunk_sectors
= 0;
3156 conf
= setup_conf(mddev
);
3158 /* Array must appear to be quiesced */
3159 conf
->array_frozen
= 1;
3162 return ERR_PTR(-EINVAL
);
3165 static struct md_personality raid1_personality
=
3169 .owner
= THIS_MODULE
,
3170 .make_request
= make_request
,
3174 .error_handler
= error
,
3175 .hot_add_disk
= raid1_add_disk
,
3176 .hot_remove_disk
= raid1_remove_disk
,
3177 .spare_active
= raid1_spare_active
,
3178 .sync_request
= sync_request
,
3179 .resize
= raid1_resize
,
3181 .check_reshape
= raid1_reshape
,
3182 .quiesce
= raid1_quiesce
,
3183 .takeover
= raid1_takeover
,
3186 static int __init
raid_init(void)
3188 return register_md_personality(&raid1_personality
);
3191 static void raid_exit(void)
3193 unregister_md_personality(&raid1_personality
);
3196 module_init(raid_init
);
3197 module_exit(raid_exit
);
3198 MODULE_LICENSE("GPL");
3199 MODULE_DESCRIPTION("RAID1 (mirroring) personality for MD");
3200 MODULE_ALIAS("md-personality-3"); /* RAID1 */
3201 MODULE_ALIAS("md-raid1");
3202 MODULE_ALIAS("md-level-1");
3204 module_param(max_queued_requests
, int, S_IRUGO
|S_IWUSR
);