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
);
70 static void lower_barrier(struct r1conf
*conf
);
72 static void * r1bio_pool_alloc(gfp_t gfp_flags
, void *data
)
74 struct pool_info
*pi
= data
;
75 int size
= offsetof(struct r1bio
, bios
[pi
->raid_disks
]);
77 /* allocate a r1bio with room for raid_disks entries in the bios array */
78 return kzalloc(size
, gfp_flags
);
81 static void r1bio_pool_free(void *r1_bio
, void *data
)
86 #define RESYNC_BLOCK_SIZE (64*1024)
87 //#define RESYNC_BLOCK_SIZE PAGE_SIZE
88 #define RESYNC_SECTORS (RESYNC_BLOCK_SIZE >> 9)
89 #define RESYNC_PAGES ((RESYNC_BLOCK_SIZE + PAGE_SIZE-1) / PAGE_SIZE)
90 #define RESYNC_WINDOW (2048*1024)
92 static void * r1buf_pool_alloc(gfp_t gfp_flags
, void *data
)
94 struct pool_info
*pi
= data
;
100 r1_bio
= r1bio_pool_alloc(gfp_flags
, pi
);
105 * Allocate bios : 1 for reading, n-1 for writing
107 for (j
= pi
->raid_disks
; j
-- ; ) {
108 bio
= bio_kmalloc(gfp_flags
, RESYNC_PAGES
);
111 r1_bio
->bios
[j
] = bio
;
114 * Allocate RESYNC_PAGES data pages and attach them to
116 * If this is a user-requested check/repair, allocate
117 * RESYNC_PAGES for each bio.
119 if (test_bit(MD_RECOVERY_REQUESTED
, &pi
->mddev
->recovery
))
124 bio
= r1_bio
->bios
[j
];
125 for (i
= 0; i
< RESYNC_PAGES
; i
++) {
126 page
= alloc_page(gfp_flags
);
130 bio
->bi_io_vec
[i
].bv_page
= page
;
134 /* If not user-requests, copy the page pointers to all bios */
135 if (!test_bit(MD_RECOVERY_REQUESTED
, &pi
->mddev
->recovery
)) {
136 for (i
=0; i
<RESYNC_PAGES
; i
++)
137 for (j
=1; j
<pi
->raid_disks
; j
++)
138 r1_bio
->bios
[j
]->bi_io_vec
[i
].bv_page
=
139 r1_bio
->bios
[0]->bi_io_vec
[i
].bv_page
;
142 r1_bio
->master_bio
= NULL
;
147 for (j
=0 ; j
< pi
->raid_disks
; j
++)
148 for (i
=0; i
< r1_bio
->bios
[j
]->bi_vcnt
; i
++)
149 put_page(r1_bio
->bios
[j
]->bi_io_vec
[i
].bv_page
);
152 while (++j
< pi
->raid_disks
)
153 bio_put(r1_bio
->bios
[j
]);
154 r1bio_pool_free(r1_bio
, data
);
158 static void r1buf_pool_free(void *__r1_bio
, void *data
)
160 struct pool_info
*pi
= data
;
162 struct r1bio
*r1bio
= __r1_bio
;
164 for (i
= 0; i
< RESYNC_PAGES
; i
++)
165 for (j
= pi
->raid_disks
; j
-- ;) {
167 r1bio
->bios
[j
]->bi_io_vec
[i
].bv_page
!=
168 r1bio
->bios
[0]->bi_io_vec
[i
].bv_page
)
169 safe_put_page(r1bio
->bios
[j
]->bi_io_vec
[i
].bv_page
);
171 for (i
=0 ; i
< pi
->raid_disks
; i
++)
172 bio_put(r1bio
->bios
[i
]);
174 r1bio_pool_free(r1bio
, data
);
177 static void put_all_bios(struct r1conf
*conf
, struct r1bio
*r1_bio
)
181 for (i
= 0; i
< conf
->raid_disks
* 2; i
++) {
182 struct bio
**bio
= r1_bio
->bios
+ i
;
183 if (!BIO_SPECIAL(*bio
))
189 static void free_r1bio(struct r1bio
*r1_bio
)
191 struct r1conf
*conf
= r1_bio
->mddev
->private;
193 put_all_bios(conf
, r1_bio
);
194 mempool_free(r1_bio
, conf
->r1bio_pool
);
197 static void put_buf(struct r1bio
*r1_bio
)
199 struct r1conf
*conf
= r1_bio
->mddev
->private;
202 for (i
= 0; i
< conf
->raid_disks
* 2; i
++) {
203 struct bio
*bio
= r1_bio
->bios
[i
];
205 rdev_dec_pending(conf
->mirrors
[i
].rdev
, r1_bio
->mddev
);
208 mempool_free(r1_bio
, conf
->r1buf_pool
);
213 static void reschedule_retry(struct r1bio
*r1_bio
)
216 struct mddev
*mddev
= r1_bio
->mddev
;
217 struct r1conf
*conf
= mddev
->private;
219 spin_lock_irqsave(&conf
->device_lock
, flags
);
220 list_add(&r1_bio
->retry_list
, &conf
->retry_list
);
222 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
224 wake_up(&conf
->wait_barrier
);
225 md_wakeup_thread(mddev
->thread
);
229 * raid_end_bio_io() is called when we have finished servicing a mirrored
230 * operation and are ready to return a success/failure code to the buffer
233 static void call_bio_endio(struct r1bio
*r1_bio
)
235 struct bio
*bio
= r1_bio
->master_bio
;
237 struct r1conf
*conf
= r1_bio
->mddev
->private;
239 if (bio
->bi_phys_segments
) {
241 spin_lock_irqsave(&conf
->device_lock
, flags
);
242 bio
->bi_phys_segments
--;
243 done
= (bio
->bi_phys_segments
== 0);
244 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
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
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
->bi_size
>> 9) - 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
;
430 set_bit(R1BIO_Uptodate
, &r1_bio
->state
);
432 /* Maybe we can clear some bad blocks. */
433 if (is_badblock(conf
->mirrors
[mirror
].rdev
,
434 r1_bio
->sector
, r1_bio
->sectors
,
435 &first_bad
, &bad_sectors
)) {
436 r1_bio
->bios
[mirror
] = IO_MADE_GOOD
;
437 set_bit(R1BIO_MadeGood
, &r1_bio
->state
);
442 if (test_bit(WriteMostly
, &conf
->mirrors
[mirror
].rdev
->flags
))
443 atomic_dec(&r1_bio
->behind_remaining
);
446 * In behind mode, we ACK the master bio once the I/O
447 * has safely reached all non-writemostly
448 * disks. Setting the Returned bit ensures that this
449 * gets done only once -- we don't ever want to return
450 * -EIO here, instead we'll wait
452 if (atomic_read(&r1_bio
->behind_remaining
) >= (atomic_read(&r1_bio
->remaining
)-1) &&
453 test_bit(R1BIO_Uptodate
, &r1_bio
->state
)) {
454 /* Maybe we can return now */
455 if (!test_and_set_bit(R1BIO_Returned
, &r1_bio
->state
)) {
456 struct bio
*mbio
= r1_bio
->master_bio
;
457 pr_debug("raid1: behind end write sectors"
459 (unsigned long long) mbio
->bi_sector
,
460 (unsigned long long) mbio
->bi_sector
+
461 (mbio
->bi_size
>> 9) - 1);
462 call_bio_endio(r1_bio
);
466 if (r1_bio
->bios
[mirror
] == NULL
)
467 rdev_dec_pending(conf
->mirrors
[mirror
].rdev
,
471 * Let's see if all mirrored write operations have finished
474 r1_bio_write_done(r1_bio
);
482 * This routine returns the disk from which the requested read should
483 * be done. There is a per-array 'next expected sequential IO' sector
484 * number - if this matches on the next IO then we use the last disk.
485 * There is also a per-disk 'last know head position' sector that is
486 * maintained from IRQ contexts, both the normal and the resync IO
487 * completion handlers update this position correctly. If there is no
488 * perfect sequential match then we pick the disk whose head is closest.
490 * If there are 2 mirrors in the same 2 devices, performance degrades
491 * because position is mirror, not device based.
493 * The rdev for the device selected will have nr_pending incremented.
495 static int read_balance(struct r1conf
*conf
, struct r1bio
*r1_bio
, int *max_sectors
)
497 const sector_t this_sector
= r1_bio
->sector
;
499 int best_good_sectors
;
500 int best_disk
, best_dist_disk
, best_pending_disk
;
504 unsigned int min_pending
;
505 struct md_rdev
*rdev
;
507 int choose_next_idle
;
511 * Check if we can balance. We can balance on the whole
512 * device if no resync is going on, or below the resync window.
513 * We take the first readable disk when above the resync window.
516 sectors
= r1_bio
->sectors
;
519 best_dist
= MaxSector
;
520 best_pending_disk
= -1;
521 min_pending
= UINT_MAX
;
522 best_good_sectors
= 0;
524 choose_next_idle
= 0;
526 if (conf
->mddev
->recovery_cp
< MaxSector
&&
527 (this_sector
+ sectors
>= conf
->next_resync
))
532 for (disk
= 0 ; disk
< conf
->raid_disks
* 2 ; disk
++) {
536 unsigned int pending
;
539 rdev
= rcu_dereference(conf
->mirrors
[disk
].rdev
);
540 if (r1_bio
->bios
[disk
] == IO_BLOCKED
542 || test_bit(Unmerged
, &rdev
->flags
)
543 || test_bit(Faulty
, &rdev
->flags
))
545 if (!test_bit(In_sync
, &rdev
->flags
) &&
546 rdev
->recovery_offset
< this_sector
+ sectors
)
548 if (test_bit(WriteMostly
, &rdev
->flags
)) {
549 /* Don't balance among write-mostly, just
550 * use the first as a last resort */
552 if (is_badblock(rdev
, this_sector
, sectors
,
553 &first_bad
, &bad_sectors
)) {
554 if (first_bad
< this_sector
)
555 /* Cannot use this */
557 best_good_sectors
= first_bad
- this_sector
;
559 best_good_sectors
= sectors
;
564 /* This is a reasonable device to use. It might
567 if (is_badblock(rdev
, this_sector
, sectors
,
568 &first_bad
, &bad_sectors
)) {
569 if (best_dist
< MaxSector
)
570 /* already have a better device */
572 if (first_bad
<= this_sector
) {
573 /* cannot read here. If this is the 'primary'
574 * device, then we must not read beyond
575 * bad_sectors from another device..
577 bad_sectors
-= (this_sector
- first_bad
);
578 if (choose_first
&& sectors
> bad_sectors
)
579 sectors
= bad_sectors
;
580 if (best_good_sectors
> sectors
)
581 best_good_sectors
= sectors
;
584 sector_t good_sectors
= first_bad
- this_sector
;
585 if (good_sectors
> best_good_sectors
) {
586 best_good_sectors
= good_sectors
;
594 best_good_sectors
= sectors
;
596 nonrot
= blk_queue_nonrot(bdev_get_queue(rdev
->bdev
));
597 has_nonrot_disk
|= nonrot
;
598 pending
= atomic_read(&rdev
->nr_pending
);
599 dist
= abs(this_sector
- conf
->mirrors
[disk
].head_position
);
604 /* Don't change to another disk for sequential reads */
605 if (conf
->mirrors
[disk
].next_seq_sect
== this_sector
607 int opt_iosize
= bdev_io_opt(rdev
->bdev
) >> 9;
608 struct raid1_info
*mirror
= &conf
->mirrors
[disk
];
612 * If buffered sequential IO size exceeds optimal
613 * iosize, check if there is idle disk. If yes, choose
614 * the idle disk. read_balance could already choose an
615 * idle disk before noticing it's a sequential IO in
616 * this disk. This doesn't matter because this disk
617 * will idle, next time it will be utilized after the
618 * first disk has IO size exceeds optimal iosize. In
619 * this way, iosize of the first disk will be optimal
620 * iosize at least. iosize of the second disk might be
621 * small, but not a big deal since when the second disk
622 * starts IO, the first disk is likely still busy.
624 if (nonrot
&& opt_iosize
> 0 &&
625 mirror
->seq_start
!= MaxSector
&&
626 mirror
->next_seq_sect
> opt_iosize
&&
627 mirror
->next_seq_sect
- opt_iosize
>=
629 choose_next_idle
= 1;
634 /* If device is idle, use it */
640 if (choose_next_idle
)
643 if (min_pending
> pending
) {
644 min_pending
= pending
;
645 best_pending_disk
= disk
;
648 if (dist
< best_dist
) {
650 best_dist_disk
= disk
;
655 * If all disks are rotational, choose the closest disk. If any disk is
656 * non-rotational, choose the disk with less pending request even the
657 * disk is rotational, which might/might not be optimal for raids with
658 * mixed ratation/non-rotational disks depending on workload.
660 if (best_disk
== -1) {
662 best_disk
= best_pending_disk
;
664 best_disk
= best_dist_disk
;
667 if (best_disk
>= 0) {
668 rdev
= rcu_dereference(conf
->mirrors
[best_disk
].rdev
);
671 atomic_inc(&rdev
->nr_pending
);
672 if (test_bit(Faulty
, &rdev
->flags
)) {
673 /* cannot risk returning a device that failed
674 * before we inc'ed nr_pending
676 rdev_dec_pending(rdev
, conf
->mddev
);
679 sectors
= best_good_sectors
;
681 if (conf
->mirrors
[best_disk
].next_seq_sect
!= this_sector
)
682 conf
->mirrors
[best_disk
].seq_start
= this_sector
;
684 conf
->mirrors
[best_disk
].next_seq_sect
= this_sector
+ sectors
;
687 *max_sectors
= sectors
;
692 static int raid1_mergeable_bvec(struct request_queue
*q
,
693 struct bvec_merge_data
*bvm
,
694 struct bio_vec
*biovec
)
696 struct mddev
*mddev
= q
->queuedata
;
697 struct r1conf
*conf
= mddev
->private;
698 sector_t sector
= bvm
->bi_sector
+ get_start_sect(bvm
->bi_bdev
);
699 int max
= biovec
->bv_len
;
701 if (mddev
->merge_check_needed
) {
704 for (disk
= 0; disk
< conf
->raid_disks
* 2; disk
++) {
705 struct md_rdev
*rdev
= rcu_dereference(
706 conf
->mirrors
[disk
].rdev
);
707 if (rdev
&& !test_bit(Faulty
, &rdev
->flags
)) {
708 struct request_queue
*q
=
709 bdev_get_queue(rdev
->bdev
);
710 if (q
->merge_bvec_fn
) {
711 bvm
->bi_sector
= sector
+
713 bvm
->bi_bdev
= rdev
->bdev
;
714 max
= min(max
, q
->merge_bvec_fn(
725 int md_raid1_congested(struct mddev
*mddev
, int bits
)
727 struct r1conf
*conf
= mddev
->private;
730 if ((bits
& (1 << BDI_async_congested
)) &&
731 conf
->pending_count
>= max_queued_requests
)
735 for (i
= 0; i
< conf
->raid_disks
* 2; i
++) {
736 struct md_rdev
*rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
737 if (rdev
&& !test_bit(Faulty
, &rdev
->flags
)) {
738 struct request_queue
*q
= bdev_get_queue(rdev
->bdev
);
742 /* Note the '|| 1' - when read_balance prefers
743 * non-congested targets, it can be removed
745 if ((bits
& (1<<BDI_async_congested
)) || 1)
746 ret
|= bdi_congested(&q
->backing_dev_info
, bits
);
748 ret
&= bdi_congested(&q
->backing_dev_info
, bits
);
754 EXPORT_SYMBOL_GPL(md_raid1_congested
);
756 static int raid1_congested(void *data
, int bits
)
758 struct mddev
*mddev
= data
;
760 return mddev_congested(mddev
, bits
) ||
761 md_raid1_congested(mddev
, bits
);
764 static void flush_pending_writes(struct r1conf
*conf
)
766 /* Any writes that have been queued but are awaiting
767 * bitmap updates get flushed here.
769 spin_lock_irq(&conf
->device_lock
);
771 if (conf
->pending_bio_list
.head
) {
773 bio
= bio_list_get(&conf
->pending_bio_list
);
774 conf
->pending_count
= 0;
775 spin_unlock_irq(&conf
->device_lock
);
776 /* flush any pending bitmap writes to
777 * disk before proceeding w/ I/O */
778 bitmap_unplug(conf
->mddev
->bitmap
);
779 wake_up(&conf
->wait_barrier
);
781 while (bio
) { /* submit pending writes */
782 struct bio
*next
= bio
->bi_next
;
784 if (unlikely((bio
->bi_rw
& REQ_DISCARD
) &&
785 !blk_queue_discard(bdev_get_queue(bio
->bi_bdev
))))
789 generic_make_request(bio
);
793 spin_unlock_irq(&conf
->device_lock
);
797 * Sometimes we need to suspend IO while we do something else,
798 * either some resync/recovery, or reconfigure the array.
799 * To do this we raise a 'barrier'.
800 * The 'barrier' is a counter that can be raised multiple times
801 * to count how many activities are happening which preclude
803 * We can only raise the barrier if there is no pending IO.
804 * i.e. if nr_pending == 0.
805 * We choose only to raise the barrier if no-one is waiting for the
806 * barrier to go down. This means that as soon as an IO request
807 * is ready, no other operations which require a barrier will start
808 * until the IO request has had a chance.
810 * So: regular IO calls 'wait_barrier'. When that returns there
811 * is no backgroup IO happening, It must arrange to call
812 * allow_barrier when it has finished its IO.
813 * backgroup IO calls must call raise_barrier. Once that returns
814 * there is no normal IO happeing. It must arrange to call
815 * lower_barrier when the particular background IO completes.
817 #define RESYNC_DEPTH 32
819 static void raise_barrier(struct r1conf
*conf
)
821 spin_lock_irq(&conf
->resync_lock
);
823 /* Wait until no block IO is waiting */
824 wait_event_lock_irq(conf
->wait_barrier
, !conf
->nr_waiting
,
827 /* block any new IO from starting */
830 /* Now wait for all pending IO to complete */
831 wait_event_lock_irq(conf
->wait_barrier
,
832 !conf
->nr_pending
&& conf
->barrier
< RESYNC_DEPTH
,
835 spin_unlock_irq(&conf
->resync_lock
);
838 static void lower_barrier(struct r1conf
*conf
)
841 BUG_ON(conf
->barrier
<= 0);
842 spin_lock_irqsave(&conf
->resync_lock
, flags
);
844 spin_unlock_irqrestore(&conf
->resync_lock
, flags
);
845 wake_up(&conf
->wait_barrier
);
848 static void wait_barrier(struct r1conf
*conf
)
850 spin_lock_irq(&conf
->resync_lock
);
853 /* Wait for the barrier to drop.
854 * However if there are already pending
855 * requests (preventing the barrier from
856 * rising completely), and the
857 * pre-process bio queue isn't empty,
858 * then don't wait, as we need to empty
859 * that queue to get the nr_pending
862 wait_event_lock_irq(conf
->wait_barrier
,
866 !bio_list_empty(current
->bio_list
)),
871 spin_unlock_irq(&conf
->resync_lock
);
874 static void allow_barrier(struct r1conf
*conf
)
877 spin_lock_irqsave(&conf
->resync_lock
, flags
);
879 spin_unlock_irqrestore(&conf
->resync_lock
, flags
);
880 wake_up(&conf
->wait_barrier
);
883 static void freeze_array(struct r1conf
*conf
)
885 /* stop syncio and normal IO and wait for everything to
887 * We increment barrier and nr_waiting, and then
888 * wait until nr_pending match nr_queued+1
889 * This is called in the context of one normal IO request
890 * that has failed. Thus any sync request that might be pending
891 * will be blocked by nr_pending, and we need to wait for
892 * pending IO requests to complete or be queued for re-try.
893 * Thus the number queued (nr_queued) plus this request (1)
894 * must match the number of pending IOs (nr_pending) before
897 spin_lock_irq(&conf
->resync_lock
);
900 wait_event_lock_irq_cmd(conf
->wait_barrier
,
901 conf
->nr_pending
== conf
->nr_queued
+1,
903 flush_pending_writes(conf
));
904 spin_unlock_irq(&conf
->resync_lock
);
906 static void unfreeze_array(struct r1conf
*conf
)
908 /* reverse the effect of the freeze */
909 spin_lock_irq(&conf
->resync_lock
);
912 wake_up(&conf
->wait_barrier
);
913 spin_unlock_irq(&conf
->resync_lock
);
917 /* duplicate the data pages for behind I/O
919 static void alloc_behind_pages(struct bio
*bio
, struct r1bio
*r1_bio
)
922 struct bio_vec
*bvec
;
923 struct bio_vec
*bvecs
= kzalloc(bio
->bi_vcnt
* sizeof(struct bio_vec
),
925 if (unlikely(!bvecs
))
928 bio_for_each_segment(bvec
, bio
, i
) {
930 bvecs
[i
].bv_page
= alloc_page(GFP_NOIO
);
931 if (unlikely(!bvecs
[i
].bv_page
))
933 memcpy(kmap(bvecs
[i
].bv_page
) + bvec
->bv_offset
,
934 kmap(bvec
->bv_page
) + bvec
->bv_offset
, bvec
->bv_len
);
935 kunmap(bvecs
[i
].bv_page
);
936 kunmap(bvec
->bv_page
);
938 r1_bio
->behind_bvecs
= bvecs
;
939 r1_bio
->behind_page_count
= bio
->bi_vcnt
;
940 set_bit(R1BIO_BehindIO
, &r1_bio
->state
);
944 for (i
= 0; i
< bio
->bi_vcnt
; i
++)
945 if (bvecs
[i
].bv_page
)
946 put_page(bvecs
[i
].bv_page
);
948 pr_debug("%dB behind alloc failed, doing sync I/O\n", bio
->bi_size
);
951 struct raid1_plug_cb
{
952 struct blk_plug_cb cb
;
953 struct bio_list pending
;
957 static void raid1_unplug(struct blk_plug_cb
*cb
, bool from_schedule
)
959 struct raid1_plug_cb
*plug
= container_of(cb
, struct raid1_plug_cb
,
961 struct mddev
*mddev
= plug
->cb
.data
;
962 struct r1conf
*conf
= mddev
->private;
965 if (from_schedule
|| current
->bio_list
) {
966 spin_lock_irq(&conf
->device_lock
);
967 bio_list_merge(&conf
->pending_bio_list
, &plug
->pending
);
968 conf
->pending_count
+= plug
->pending_cnt
;
969 spin_unlock_irq(&conf
->device_lock
);
970 wake_up(&conf
->wait_barrier
);
971 md_wakeup_thread(mddev
->thread
);
976 /* we aren't scheduling, so we can do the write-out directly. */
977 bio
= bio_list_get(&plug
->pending
);
978 bitmap_unplug(mddev
->bitmap
);
979 wake_up(&conf
->wait_barrier
);
981 while (bio
) { /* submit pending writes */
982 struct bio
*next
= bio
->bi_next
;
984 if (unlikely((bio
->bi_rw
& REQ_DISCARD
) &&
985 !blk_queue_discard(bdev_get_queue(bio
->bi_bdev
))))
989 generic_make_request(bio
);
995 static void make_request(struct mddev
*mddev
, struct bio
* bio
)
997 struct r1conf
*conf
= mddev
->private;
998 struct raid1_info
*mirror
;
999 struct r1bio
*r1_bio
;
1000 struct bio
*read_bio
;
1002 struct bitmap
*bitmap
;
1003 unsigned long flags
;
1004 const int rw
= bio_data_dir(bio
);
1005 const unsigned long do_sync
= (bio
->bi_rw
& REQ_SYNC
);
1006 const unsigned long do_flush_fua
= (bio
->bi_rw
& (REQ_FLUSH
| REQ_FUA
));
1007 const unsigned long do_discard
= (bio
->bi_rw
1008 & (REQ_DISCARD
| REQ_SECURE
));
1009 const unsigned long do_same
= (bio
->bi_rw
& REQ_WRITE_SAME
);
1010 struct md_rdev
*blocked_rdev
;
1011 struct blk_plug_cb
*cb
;
1012 struct raid1_plug_cb
*plug
= NULL
;
1014 int sectors_handled
;
1018 * Register the new request and wait if the reconstruction
1019 * thread has put up a bar for new requests.
1020 * Continue immediately if no resync is active currently.
1023 md_write_start(mddev
, bio
); /* wait on superblock update early */
1025 if (bio_data_dir(bio
) == WRITE
&&
1026 bio
->bi_sector
+ bio
->bi_size
/512 > mddev
->suspend_lo
&&
1027 bio
->bi_sector
< mddev
->suspend_hi
) {
1028 /* As the suspend_* range is controlled by
1029 * userspace, we want an interruptible
1034 flush_signals(current
);
1035 prepare_to_wait(&conf
->wait_barrier
,
1036 &w
, TASK_INTERRUPTIBLE
);
1037 if (bio
->bi_sector
+ bio
->bi_size
/512 <= mddev
->suspend_lo
||
1038 bio
->bi_sector
>= mddev
->suspend_hi
)
1042 finish_wait(&conf
->wait_barrier
, &w
);
1047 bitmap
= mddev
->bitmap
;
1050 * make_request() can abort the operation when READA is being
1051 * used and no empty request is available.
1054 r1_bio
= mempool_alloc(conf
->r1bio_pool
, GFP_NOIO
);
1056 r1_bio
->master_bio
= bio
;
1057 r1_bio
->sectors
= bio
->bi_size
>> 9;
1059 r1_bio
->mddev
= mddev
;
1060 r1_bio
->sector
= bio
->bi_sector
;
1062 /* We might need to issue multiple reads to different
1063 * devices if there are bad blocks around, so we keep
1064 * track of the number of reads in bio->bi_phys_segments.
1065 * If this is 0, there is only one r1_bio and no locking
1066 * will be needed when requests complete. If it is
1067 * non-zero, then it is the number of not-completed requests.
1069 bio
->bi_phys_segments
= 0;
1070 clear_bit(BIO_SEG_VALID
, &bio
->bi_flags
);
1074 * read balancing logic:
1079 rdisk
= read_balance(conf
, r1_bio
, &max_sectors
);
1082 /* couldn't find anywhere to read from */
1083 raid_end_bio_io(r1_bio
);
1086 mirror
= conf
->mirrors
+ rdisk
;
1088 if (test_bit(WriteMostly
, &mirror
->rdev
->flags
) &&
1090 /* Reading from a write-mostly device must
1091 * take care not to over-take any writes
1094 wait_event(bitmap
->behind_wait
,
1095 atomic_read(&bitmap
->behind_writes
) == 0);
1097 r1_bio
->read_disk
= rdisk
;
1099 read_bio
= bio_clone_mddev(bio
, GFP_NOIO
, mddev
);
1100 md_trim_bio(read_bio
, r1_bio
->sector
- bio
->bi_sector
,
1103 r1_bio
->bios
[rdisk
] = read_bio
;
1105 read_bio
->bi_sector
= r1_bio
->sector
+ mirror
->rdev
->data_offset
;
1106 read_bio
->bi_bdev
= mirror
->rdev
->bdev
;
1107 read_bio
->bi_end_io
= raid1_end_read_request
;
1108 read_bio
->bi_rw
= READ
| do_sync
;
1109 read_bio
->bi_private
= r1_bio
;
1111 if (max_sectors
< r1_bio
->sectors
) {
1112 /* could not read all from this device, so we will
1113 * need another r1_bio.
1116 sectors_handled
= (r1_bio
->sector
+ max_sectors
1118 r1_bio
->sectors
= max_sectors
;
1119 spin_lock_irq(&conf
->device_lock
);
1120 if (bio
->bi_phys_segments
== 0)
1121 bio
->bi_phys_segments
= 2;
1123 bio
->bi_phys_segments
++;
1124 spin_unlock_irq(&conf
->device_lock
);
1125 /* Cannot call generic_make_request directly
1126 * as that will be queued in __make_request
1127 * and subsequent mempool_alloc might block waiting
1128 * for it. So hand bio over to raid1d.
1130 reschedule_retry(r1_bio
);
1132 r1_bio
= mempool_alloc(conf
->r1bio_pool
, GFP_NOIO
);
1134 r1_bio
->master_bio
= bio
;
1135 r1_bio
->sectors
= (bio
->bi_size
>> 9) - sectors_handled
;
1137 r1_bio
->mddev
= mddev
;
1138 r1_bio
->sector
= bio
->bi_sector
+ sectors_handled
;
1141 generic_make_request(read_bio
);
1148 if (conf
->pending_count
>= max_queued_requests
) {
1149 md_wakeup_thread(mddev
->thread
);
1150 wait_event(conf
->wait_barrier
,
1151 conf
->pending_count
< max_queued_requests
);
1153 /* first select target devices under rcu_lock and
1154 * inc refcount on their rdev. Record them by setting
1156 * If there are known/acknowledged bad blocks on any device on
1157 * which we have seen a write error, we want to avoid writing those
1159 * This potentially requires several writes to write around
1160 * the bad blocks. Each set of writes gets it's own r1bio
1161 * with a set of bios attached.
1164 disks
= conf
->raid_disks
* 2;
1166 blocked_rdev
= NULL
;
1168 max_sectors
= r1_bio
->sectors
;
1169 for (i
= 0; i
< disks
; i
++) {
1170 struct md_rdev
*rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
1171 if (rdev
&& unlikely(test_bit(Blocked
, &rdev
->flags
))) {
1172 atomic_inc(&rdev
->nr_pending
);
1173 blocked_rdev
= rdev
;
1176 r1_bio
->bios
[i
] = NULL
;
1177 if (!rdev
|| test_bit(Faulty
, &rdev
->flags
)
1178 || test_bit(Unmerged
, &rdev
->flags
)) {
1179 if (i
< conf
->raid_disks
)
1180 set_bit(R1BIO_Degraded
, &r1_bio
->state
);
1184 atomic_inc(&rdev
->nr_pending
);
1185 if (test_bit(WriteErrorSeen
, &rdev
->flags
)) {
1190 is_bad
= is_badblock(rdev
, r1_bio
->sector
,
1192 &first_bad
, &bad_sectors
);
1194 /* mustn't write here until the bad block is
1196 set_bit(BlockedBadBlocks
, &rdev
->flags
);
1197 blocked_rdev
= rdev
;
1200 if (is_bad
&& first_bad
<= r1_bio
->sector
) {
1201 /* Cannot write here at all */
1202 bad_sectors
-= (r1_bio
->sector
- first_bad
);
1203 if (bad_sectors
< max_sectors
)
1204 /* mustn't write more than bad_sectors
1205 * to other devices yet
1207 max_sectors
= bad_sectors
;
1208 rdev_dec_pending(rdev
, mddev
);
1209 /* We don't set R1BIO_Degraded as that
1210 * only applies if the disk is
1211 * missing, so it might be re-added,
1212 * and we want to know to recover this
1214 * In this case the device is here,
1215 * and the fact that this chunk is not
1216 * in-sync is recorded in the bad
1222 int good_sectors
= first_bad
- r1_bio
->sector
;
1223 if (good_sectors
< max_sectors
)
1224 max_sectors
= good_sectors
;
1227 r1_bio
->bios
[i
] = bio
;
1231 if (unlikely(blocked_rdev
)) {
1232 /* Wait for this device to become unblocked */
1235 for (j
= 0; j
< i
; j
++)
1236 if (r1_bio
->bios
[j
])
1237 rdev_dec_pending(conf
->mirrors
[j
].rdev
, mddev
);
1239 allow_barrier(conf
);
1240 md_wait_for_blocked_rdev(blocked_rdev
, mddev
);
1245 if (max_sectors
< r1_bio
->sectors
) {
1246 /* We are splitting this write into multiple parts, so
1247 * we need to prepare for allocating another r1_bio.
1249 r1_bio
->sectors
= max_sectors
;
1250 spin_lock_irq(&conf
->device_lock
);
1251 if (bio
->bi_phys_segments
== 0)
1252 bio
->bi_phys_segments
= 2;
1254 bio
->bi_phys_segments
++;
1255 spin_unlock_irq(&conf
->device_lock
);
1257 sectors_handled
= r1_bio
->sector
+ max_sectors
- bio
->bi_sector
;
1259 atomic_set(&r1_bio
->remaining
, 1);
1260 atomic_set(&r1_bio
->behind_remaining
, 0);
1263 for (i
= 0; i
< disks
; i
++) {
1265 if (!r1_bio
->bios
[i
])
1268 mbio
= bio_clone_mddev(bio
, GFP_NOIO
, mddev
);
1269 md_trim_bio(mbio
, r1_bio
->sector
- bio
->bi_sector
, max_sectors
);
1273 * Not if there are too many, or cannot
1274 * allocate memory, or a reader on WriteMostly
1275 * is waiting for behind writes to flush */
1277 (atomic_read(&bitmap
->behind_writes
)
1278 < mddev
->bitmap_info
.max_write_behind
) &&
1279 !waitqueue_active(&bitmap
->behind_wait
))
1280 alloc_behind_pages(mbio
, r1_bio
);
1282 bitmap_startwrite(bitmap
, r1_bio
->sector
,
1284 test_bit(R1BIO_BehindIO
,
1288 if (r1_bio
->behind_bvecs
) {
1289 struct bio_vec
*bvec
;
1292 /* Yes, I really want the '__' version so that
1293 * we clear any unused pointer in the io_vec, rather
1294 * than leave them unchanged. This is important
1295 * because when we come to free the pages, we won't
1296 * know the original bi_idx, so we just free
1299 __bio_for_each_segment(bvec
, mbio
, j
, 0)
1300 bvec
->bv_page
= r1_bio
->behind_bvecs
[j
].bv_page
;
1301 if (test_bit(WriteMostly
, &conf
->mirrors
[i
].rdev
->flags
))
1302 atomic_inc(&r1_bio
->behind_remaining
);
1305 r1_bio
->bios
[i
] = mbio
;
1307 mbio
->bi_sector
= (r1_bio
->sector
+
1308 conf
->mirrors
[i
].rdev
->data_offset
);
1309 mbio
->bi_bdev
= conf
->mirrors
[i
].rdev
->bdev
;
1310 mbio
->bi_end_io
= raid1_end_write_request
;
1312 WRITE
| do_flush_fua
| do_sync
| do_discard
| do_same
;
1313 mbio
->bi_private
= r1_bio
;
1315 atomic_inc(&r1_bio
->remaining
);
1317 cb
= blk_check_plugged(raid1_unplug
, mddev
, sizeof(*plug
));
1319 plug
= container_of(cb
, struct raid1_plug_cb
, cb
);
1322 spin_lock_irqsave(&conf
->device_lock
, flags
);
1324 bio_list_add(&plug
->pending
, mbio
);
1325 plug
->pending_cnt
++;
1327 bio_list_add(&conf
->pending_bio_list
, mbio
);
1328 conf
->pending_count
++;
1330 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
1332 md_wakeup_thread(mddev
->thread
);
1334 /* Mustn't call r1_bio_write_done before this next test,
1335 * as it could result in the bio being freed.
1337 if (sectors_handled
< (bio
->bi_size
>> 9)) {
1338 r1_bio_write_done(r1_bio
);
1339 /* We need another r1_bio. It has already been counted
1340 * in bio->bi_phys_segments
1342 r1_bio
= mempool_alloc(conf
->r1bio_pool
, GFP_NOIO
);
1343 r1_bio
->master_bio
= bio
;
1344 r1_bio
->sectors
= (bio
->bi_size
>> 9) - sectors_handled
;
1346 r1_bio
->mddev
= mddev
;
1347 r1_bio
->sector
= bio
->bi_sector
+ sectors_handled
;
1351 r1_bio_write_done(r1_bio
);
1353 /* In case raid1d snuck in to freeze_array */
1354 wake_up(&conf
->wait_barrier
);
1357 static void status(struct seq_file
*seq
, struct mddev
*mddev
)
1359 struct r1conf
*conf
= mddev
->private;
1362 seq_printf(seq
, " [%d/%d] [", conf
->raid_disks
,
1363 conf
->raid_disks
- mddev
->degraded
);
1365 for (i
= 0; i
< conf
->raid_disks
; i
++) {
1366 struct md_rdev
*rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
1367 seq_printf(seq
, "%s",
1368 rdev
&& test_bit(In_sync
, &rdev
->flags
) ? "U" : "_");
1371 seq_printf(seq
, "]");
1375 static void error(struct mddev
*mddev
, struct md_rdev
*rdev
)
1377 char b
[BDEVNAME_SIZE
];
1378 struct r1conf
*conf
= mddev
->private;
1381 * If it is not operational, then we have already marked it as dead
1382 * else if it is the last working disks, ignore the error, let the
1383 * next level up know.
1384 * else mark the drive as failed
1386 if (test_bit(In_sync
, &rdev
->flags
)
1387 && (conf
->raid_disks
- mddev
->degraded
) == 1) {
1389 * Don't fail the drive, act as though we were just a
1390 * normal single drive.
1391 * However don't try a recovery from this drive as
1392 * it is very likely to fail.
1394 conf
->recovery_disabled
= mddev
->recovery_disabled
;
1397 set_bit(Blocked
, &rdev
->flags
);
1398 if (test_and_clear_bit(In_sync
, &rdev
->flags
)) {
1399 unsigned long flags
;
1400 spin_lock_irqsave(&conf
->device_lock
, flags
);
1402 set_bit(Faulty
, &rdev
->flags
);
1403 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
1405 * if recovery is running, make sure it aborts.
1407 set_bit(MD_RECOVERY_INTR
, &mddev
->recovery
);
1409 set_bit(Faulty
, &rdev
->flags
);
1410 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
1412 "md/raid1:%s: Disk failure on %s, disabling device.\n"
1413 "md/raid1:%s: Operation continuing on %d devices.\n",
1414 mdname(mddev
), bdevname(rdev
->bdev
, b
),
1415 mdname(mddev
), conf
->raid_disks
- mddev
->degraded
);
1418 static void print_conf(struct r1conf
*conf
)
1422 printk(KERN_DEBUG
"RAID1 conf printout:\n");
1424 printk(KERN_DEBUG
"(!conf)\n");
1427 printk(KERN_DEBUG
" --- wd:%d rd:%d\n", conf
->raid_disks
- conf
->mddev
->degraded
,
1431 for (i
= 0; i
< conf
->raid_disks
; i
++) {
1432 char b
[BDEVNAME_SIZE
];
1433 struct md_rdev
*rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
1435 printk(KERN_DEBUG
" disk %d, wo:%d, o:%d, dev:%s\n",
1436 i
, !test_bit(In_sync
, &rdev
->flags
),
1437 !test_bit(Faulty
, &rdev
->flags
),
1438 bdevname(rdev
->bdev
,b
));
1443 static void close_sync(struct r1conf
*conf
)
1446 allow_barrier(conf
);
1448 mempool_destroy(conf
->r1buf_pool
);
1449 conf
->r1buf_pool
= NULL
;
1452 static int raid1_spare_active(struct mddev
*mddev
)
1455 struct r1conf
*conf
= mddev
->private;
1457 unsigned long flags
;
1460 * Find all failed disks within the RAID1 configuration
1461 * and mark them readable.
1462 * Called under mddev lock, so rcu protection not needed.
1464 for (i
= 0; i
< conf
->raid_disks
; i
++) {
1465 struct md_rdev
*rdev
= conf
->mirrors
[i
].rdev
;
1466 struct md_rdev
*repl
= conf
->mirrors
[conf
->raid_disks
+ i
].rdev
;
1468 && repl
->recovery_offset
== MaxSector
1469 && !test_bit(Faulty
, &repl
->flags
)
1470 && !test_and_set_bit(In_sync
, &repl
->flags
)) {
1471 /* replacement has just become active */
1473 !test_and_clear_bit(In_sync
, &rdev
->flags
))
1476 /* Replaced device not technically
1477 * faulty, but we need to be sure
1478 * it gets removed and never re-added
1480 set_bit(Faulty
, &rdev
->flags
);
1481 sysfs_notify_dirent_safe(
1486 && !test_bit(Faulty
, &rdev
->flags
)
1487 && !test_and_set_bit(In_sync
, &rdev
->flags
)) {
1489 sysfs_notify_dirent_safe(rdev
->sysfs_state
);
1492 spin_lock_irqsave(&conf
->device_lock
, flags
);
1493 mddev
->degraded
-= count
;
1494 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
1501 static int raid1_add_disk(struct mddev
*mddev
, struct md_rdev
*rdev
)
1503 struct r1conf
*conf
= mddev
->private;
1506 struct raid1_info
*p
;
1508 int last
= conf
->raid_disks
- 1;
1509 struct request_queue
*q
= bdev_get_queue(rdev
->bdev
);
1511 if (mddev
->recovery_disabled
== conf
->recovery_disabled
)
1514 if (rdev
->raid_disk
>= 0)
1515 first
= last
= rdev
->raid_disk
;
1517 if (q
->merge_bvec_fn
) {
1518 set_bit(Unmerged
, &rdev
->flags
);
1519 mddev
->merge_check_needed
= 1;
1522 for (mirror
= first
; mirror
<= last
; mirror
++) {
1523 p
= conf
->mirrors
+mirror
;
1526 disk_stack_limits(mddev
->gendisk
, rdev
->bdev
,
1527 rdev
->data_offset
<< 9);
1529 p
->head_position
= 0;
1530 rdev
->raid_disk
= mirror
;
1532 /* As all devices are equivalent, we don't need a full recovery
1533 * if this was recently any drive of the array
1535 if (rdev
->saved_raid_disk
< 0)
1537 rcu_assign_pointer(p
->rdev
, rdev
);
1540 if (test_bit(WantReplacement
, &p
->rdev
->flags
) &&
1541 p
[conf
->raid_disks
].rdev
== NULL
) {
1542 /* Add this device as a replacement */
1543 clear_bit(In_sync
, &rdev
->flags
);
1544 set_bit(Replacement
, &rdev
->flags
);
1545 rdev
->raid_disk
= mirror
;
1548 rcu_assign_pointer(p
[conf
->raid_disks
].rdev
, rdev
);
1552 if (err
== 0 && test_bit(Unmerged
, &rdev
->flags
)) {
1553 /* Some requests might not have seen this new
1554 * merge_bvec_fn. We must wait for them to complete
1555 * before merging the device fully.
1556 * First we make sure any code which has tested
1557 * our function has submitted the request, then
1558 * we wait for all outstanding requests to complete.
1560 synchronize_sched();
1561 raise_barrier(conf
);
1562 lower_barrier(conf
);
1563 clear_bit(Unmerged
, &rdev
->flags
);
1565 md_integrity_add_rdev(rdev
, mddev
);
1566 if (blk_queue_discard(bdev_get_queue(rdev
->bdev
)))
1567 queue_flag_set_unlocked(QUEUE_FLAG_DISCARD
, mddev
->queue
);
1572 static int raid1_remove_disk(struct mddev
*mddev
, struct md_rdev
*rdev
)
1574 struct r1conf
*conf
= mddev
->private;
1576 int number
= rdev
->raid_disk
;
1577 struct raid1_info
*p
= conf
->mirrors
+ number
;
1579 if (rdev
!= p
->rdev
)
1580 p
= conf
->mirrors
+ conf
->raid_disks
+ number
;
1583 if (rdev
== p
->rdev
) {
1584 if (test_bit(In_sync
, &rdev
->flags
) ||
1585 atomic_read(&rdev
->nr_pending
)) {
1589 /* Only remove non-faulty devices if recovery
1592 if (!test_bit(Faulty
, &rdev
->flags
) &&
1593 mddev
->recovery_disabled
!= conf
->recovery_disabled
&&
1594 mddev
->degraded
< conf
->raid_disks
) {
1600 if (atomic_read(&rdev
->nr_pending
)) {
1601 /* lost the race, try later */
1605 } else if (conf
->mirrors
[conf
->raid_disks
+ number
].rdev
) {
1606 /* We just removed a device that is being replaced.
1607 * Move down the replacement. We drain all IO before
1608 * doing this to avoid confusion.
1610 struct md_rdev
*repl
=
1611 conf
->mirrors
[conf
->raid_disks
+ number
].rdev
;
1612 raise_barrier(conf
);
1613 clear_bit(Replacement
, &repl
->flags
);
1615 conf
->mirrors
[conf
->raid_disks
+ number
].rdev
= NULL
;
1616 lower_barrier(conf
);
1617 clear_bit(WantReplacement
, &rdev
->flags
);
1619 clear_bit(WantReplacement
, &rdev
->flags
);
1620 err
= md_integrity_register(mddev
);
1629 static void end_sync_read(struct bio
*bio
, int error
)
1631 struct r1bio
*r1_bio
= bio
->bi_private
;
1633 update_head_pos(r1_bio
->read_disk
, r1_bio
);
1636 * we have read a block, now it needs to be re-written,
1637 * or re-read if the read failed.
1638 * We don't do much here, just schedule handling by raid1d
1640 if (test_bit(BIO_UPTODATE
, &bio
->bi_flags
))
1641 set_bit(R1BIO_Uptodate
, &r1_bio
->state
);
1643 if (atomic_dec_and_test(&r1_bio
->remaining
))
1644 reschedule_retry(r1_bio
);
1647 static void end_sync_write(struct bio
*bio
, int error
)
1649 int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
1650 struct r1bio
*r1_bio
= bio
->bi_private
;
1651 struct mddev
*mddev
= r1_bio
->mddev
;
1652 struct r1conf
*conf
= mddev
->private;
1657 mirror
= find_bio_disk(r1_bio
, bio
);
1660 sector_t sync_blocks
= 0;
1661 sector_t s
= r1_bio
->sector
;
1662 long sectors_to_go
= r1_bio
->sectors
;
1663 /* make sure these bits doesn't get cleared. */
1665 bitmap_end_sync(mddev
->bitmap
, s
,
1668 sectors_to_go
-= sync_blocks
;
1669 } while (sectors_to_go
> 0);
1670 set_bit(WriteErrorSeen
,
1671 &conf
->mirrors
[mirror
].rdev
->flags
);
1672 if (!test_and_set_bit(WantReplacement
,
1673 &conf
->mirrors
[mirror
].rdev
->flags
))
1674 set_bit(MD_RECOVERY_NEEDED
, &
1676 set_bit(R1BIO_WriteError
, &r1_bio
->state
);
1677 } else if (is_badblock(conf
->mirrors
[mirror
].rdev
,
1680 &first_bad
, &bad_sectors
) &&
1681 !is_badblock(conf
->mirrors
[r1_bio
->read_disk
].rdev
,
1684 &first_bad
, &bad_sectors
)
1686 set_bit(R1BIO_MadeGood
, &r1_bio
->state
);
1688 if (atomic_dec_and_test(&r1_bio
->remaining
)) {
1689 int s
= r1_bio
->sectors
;
1690 if (test_bit(R1BIO_MadeGood
, &r1_bio
->state
) ||
1691 test_bit(R1BIO_WriteError
, &r1_bio
->state
))
1692 reschedule_retry(r1_bio
);
1695 md_done_sync(mddev
, s
, uptodate
);
1700 static int r1_sync_page_io(struct md_rdev
*rdev
, sector_t sector
,
1701 int sectors
, struct page
*page
, int rw
)
1703 if (sync_page_io(rdev
, sector
, sectors
<< 9, page
, rw
, false))
1707 set_bit(WriteErrorSeen
, &rdev
->flags
);
1708 if (!test_and_set_bit(WantReplacement
,
1710 set_bit(MD_RECOVERY_NEEDED
, &
1711 rdev
->mddev
->recovery
);
1713 /* need to record an error - either for the block or the device */
1714 if (!rdev_set_badblocks(rdev
, sector
, sectors
, 0))
1715 md_error(rdev
->mddev
, rdev
);
1719 static int fix_sync_read_error(struct r1bio
*r1_bio
)
1721 /* Try some synchronous reads of other devices to get
1722 * good data, much like with normal read errors. Only
1723 * read into the pages we already have so we don't
1724 * need to re-issue the read request.
1725 * We don't need to freeze the array, because being in an
1726 * active sync request, there is no normal IO, and
1727 * no overlapping syncs.
1728 * We don't need to check is_badblock() again as we
1729 * made sure that anything with a bad block in range
1730 * will have bi_end_io clear.
1732 struct mddev
*mddev
= r1_bio
->mddev
;
1733 struct r1conf
*conf
= mddev
->private;
1734 struct bio
*bio
= r1_bio
->bios
[r1_bio
->read_disk
];
1735 sector_t sect
= r1_bio
->sector
;
1736 int sectors
= r1_bio
->sectors
;
1741 int d
= r1_bio
->read_disk
;
1743 struct md_rdev
*rdev
;
1746 if (s
> (PAGE_SIZE
>>9))
1749 if (r1_bio
->bios
[d
]->bi_end_io
== end_sync_read
) {
1750 /* No rcu protection needed here devices
1751 * can only be removed when no resync is
1752 * active, and resync is currently active
1754 rdev
= conf
->mirrors
[d
].rdev
;
1755 if (sync_page_io(rdev
, sect
, s
<<9,
1756 bio
->bi_io_vec
[idx
].bv_page
,
1763 if (d
== conf
->raid_disks
* 2)
1765 } while (!success
&& d
!= r1_bio
->read_disk
);
1768 char b
[BDEVNAME_SIZE
];
1770 /* Cannot read from anywhere, this block is lost.
1771 * Record a bad block on each device. If that doesn't
1772 * work just disable and interrupt the recovery.
1773 * Don't fail devices as that won't really help.
1775 printk(KERN_ALERT
"md/raid1:%s: %s: unrecoverable I/O read error"
1776 " for block %llu\n",
1778 bdevname(bio
->bi_bdev
, b
),
1779 (unsigned long long)r1_bio
->sector
);
1780 for (d
= 0; d
< conf
->raid_disks
* 2; d
++) {
1781 rdev
= conf
->mirrors
[d
].rdev
;
1782 if (!rdev
|| test_bit(Faulty
, &rdev
->flags
))
1784 if (!rdev_set_badblocks(rdev
, sect
, s
, 0))
1788 conf
->recovery_disabled
=
1789 mddev
->recovery_disabled
;
1790 set_bit(MD_RECOVERY_INTR
, &mddev
->recovery
);
1791 md_done_sync(mddev
, r1_bio
->sectors
, 0);
1803 /* write it back and re-read */
1804 while (d
!= r1_bio
->read_disk
) {
1806 d
= conf
->raid_disks
* 2;
1808 if (r1_bio
->bios
[d
]->bi_end_io
!= end_sync_read
)
1810 rdev
= conf
->mirrors
[d
].rdev
;
1811 if (r1_sync_page_io(rdev
, sect
, s
,
1812 bio
->bi_io_vec
[idx
].bv_page
,
1814 r1_bio
->bios
[d
]->bi_end_io
= NULL
;
1815 rdev_dec_pending(rdev
, mddev
);
1819 while (d
!= r1_bio
->read_disk
) {
1821 d
= conf
->raid_disks
* 2;
1823 if (r1_bio
->bios
[d
]->bi_end_io
!= end_sync_read
)
1825 rdev
= conf
->mirrors
[d
].rdev
;
1826 if (r1_sync_page_io(rdev
, sect
, s
,
1827 bio
->bi_io_vec
[idx
].bv_page
,
1829 atomic_add(s
, &rdev
->corrected_errors
);
1835 set_bit(R1BIO_Uptodate
, &r1_bio
->state
);
1836 set_bit(BIO_UPTODATE
, &bio
->bi_flags
);
1840 static int process_checks(struct r1bio
*r1_bio
)
1842 /* We have read all readable devices. If we haven't
1843 * got the block, then there is no hope left.
1844 * If we have, then we want to do a comparison
1845 * and skip the write if everything is the same.
1846 * If any blocks failed to read, then we need to
1847 * attempt an over-write
1849 struct mddev
*mddev
= r1_bio
->mddev
;
1850 struct r1conf
*conf
= mddev
->private;
1855 for (primary
= 0; primary
< conf
->raid_disks
* 2; primary
++)
1856 if (r1_bio
->bios
[primary
]->bi_end_io
== end_sync_read
&&
1857 test_bit(BIO_UPTODATE
, &r1_bio
->bios
[primary
]->bi_flags
)) {
1858 r1_bio
->bios
[primary
]->bi_end_io
= NULL
;
1859 rdev_dec_pending(conf
->mirrors
[primary
].rdev
, mddev
);
1862 r1_bio
->read_disk
= primary
;
1863 vcnt
= (r1_bio
->sectors
+ PAGE_SIZE
/ 512 - 1) >> (PAGE_SHIFT
- 9);
1864 for (i
= 0; i
< conf
->raid_disks
* 2; i
++) {
1866 struct bio
*pbio
= r1_bio
->bios
[primary
];
1867 struct bio
*sbio
= r1_bio
->bios
[i
];
1870 if (r1_bio
->bios
[i
]->bi_end_io
!= end_sync_read
)
1873 if (test_bit(BIO_UPTODATE
, &sbio
->bi_flags
)) {
1874 for (j
= vcnt
; j
-- ; ) {
1876 p
= pbio
->bi_io_vec
[j
].bv_page
;
1877 s
= sbio
->bi_io_vec
[j
].bv_page
;
1878 if (memcmp(page_address(p
),
1880 sbio
->bi_io_vec
[j
].bv_len
))
1886 atomic64_add(r1_bio
->sectors
, &mddev
->resync_mismatches
);
1887 if (j
< 0 || (test_bit(MD_RECOVERY_CHECK
, &mddev
->recovery
)
1888 && test_bit(BIO_UPTODATE
, &sbio
->bi_flags
))) {
1889 /* No need to write to this device. */
1890 sbio
->bi_end_io
= NULL
;
1891 rdev_dec_pending(conf
->mirrors
[i
].rdev
, mddev
);
1894 /* fixup the bio for reuse */
1895 sbio
->bi_vcnt
= vcnt
;
1896 sbio
->bi_size
= r1_bio
->sectors
<< 9;
1898 sbio
->bi_phys_segments
= 0;
1899 sbio
->bi_flags
&= ~(BIO_POOL_MASK
- 1);
1900 sbio
->bi_flags
|= 1 << BIO_UPTODATE
;
1901 sbio
->bi_next
= NULL
;
1902 sbio
->bi_sector
= r1_bio
->sector
+
1903 conf
->mirrors
[i
].rdev
->data_offset
;
1904 sbio
->bi_bdev
= conf
->mirrors
[i
].rdev
->bdev
;
1905 size
= sbio
->bi_size
;
1906 for (j
= 0; j
< vcnt
; j
++) {
1908 bi
= &sbio
->bi_io_vec
[j
];
1910 if (size
> PAGE_SIZE
)
1911 bi
->bv_len
= PAGE_SIZE
;
1915 memcpy(page_address(bi
->bv_page
),
1916 page_address(pbio
->bi_io_vec
[j
].bv_page
),
1923 static void sync_request_write(struct mddev
*mddev
, struct r1bio
*r1_bio
)
1925 struct r1conf
*conf
= mddev
->private;
1927 int disks
= conf
->raid_disks
* 2;
1928 struct bio
*bio
, *wbio
;
1930 bio
= r1_bio
->bios
[r1_bio
->read_disk
];
1932 if (!test_bit(R1BIO_Uptodate
, &r1_bio
->state
))
1933 /* ouch - failed to read all of that. */
1934 if (!fix_sync_read_error(r1_bio
))
1937 if (test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
))
1938 if (process_checks(r1_bio
) < 0)
1943 atomic_set(&r1_bio
->remaining
, 1);
1944 for (i
= 0; i
< disks
; i
++) {
1945 wbio
= r1_bio
->bios
[i
];
1946 if (wbio
->bi_end_io
== NULL
||
1947 (wbio
->bi_end_io
== end_sync_read
&&
1948 (i
== r1_bio
->read_disk
||
1949 !test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
))))
1952 wbio
->bi_rw
= WRITE
;
1953 wbio
->bi_end_io
= end_sync_write
;
1954 atomic_inc(&r1_bio
->remaining
);
1955 md_sync_acct(conf
->mirrors
[i
].rdev
->bdev
, wbio
->bi_size
>> 9);
1957 generic_make_request(wbio
);
1960 if (atomic_dec_and_test(&r1_bio
->remaining
)) {
1961 /* if we're here, all write(s) have completed, so clean up */
1962 int s
= r1_bio
->sectors
;
1963 if (test_bit(R1BIO_MadeGood
, &r1_bio
->state
) ||
1964 test_bit(R1BIO_WriteError
, &r1_bio
->state
))
1965 reschedule_retry(r1_bio
);
1968 md_done_sync(mddev
, s
, 1);
1974 * This is a kernel thread which:
1976 * 1. Retries failed read operations on working mirrors.
1977 * 2. Updates the raid superblock when problems encounter.
1978 * 3. Performs writes following reads for array synchronising.
1981 static void fix_read_error(struct r1conf
*conf
, int read_disk
,
1982 sector_t sect
, int sectors
)
1984 struct mddev
*mddev
= conf
->mddev
;
1990 struct md_rdev
*rdev
;
1992 if (s
> (PAGE_SIZE
>>9))
1996 /* Note: no rcu protection needed here
1997 * as this is synchronous in the raid1d thread
1998 * which is the thread that might remove
1999 * a device. If raid1d ever becomes multi-threaded....
2004 rdev
= conf
->mirrors
[d
].rdev
;
2006 (test_bit(In_sync
, &rdev
->flags
) ||
2007 (!test_bit(Faulty
, &rdev
->flags
) &&
2008 rdev
->recovery_offset
>= sect
+ s
)) &&
2009 is_badblock(rdev
, sect
, s
,
2010 &first_bad
, &bad_sectors
) == 0 &&
2011 sync_page_io(rdev
, sect
, s
<<9,
2012 conf
->tmppage
, READ
, false))
2016 if (d
== conf
->raid_disks
* 2)
2019 } while (!success
&& d
!= read_disk
);
2022 /* Cannot read from anywhere - mark it bad */
2023 struct md_rdev
*rdev
= conf
->mirrors
[read_disk
].rdev
;
2024 if (!rdev_set_badblocks(rdev
, sect
, s
, 0))
2025 md_error(mddev
, rdev
);
2028 /* write it back and re-read */
2030 while (d
!= read_disk
) {
2032 d
= conf
->raid_disks
* 2;
2034 rdev
= conf
->mirrors
[d
].rdev
;
2036 test_bit(In_sync
, &rdev
->flags
))
2037 r1_sync_page_io(rdev
, sect
, s
,
2038 conf
->tmppage
, WRITE
);
2041 while (d
!= read_disk
) {
2042 char b
[BDEVNAME_SIZE
];
2044 d
= conf
->raid_disks
* 2;
2046 rdev
= conf
->mirrors
[d
].rdev
;
2048 test_bit(In_sync
, &rdev
->flags
)) {
2049 if (r1_sync_page_io(rdev
, sect
, s
,
2050 conf
->tmppage
, READ
)) {
2051 atomic_add(s
, &rdev
->corrected_errors
);
2053 "md/raid1:%s: read error corrected "
2054 "(%d sectors at %llu on %s)\n",
2056 (unsigned long long)(sect
+
2058 bdevname(rdev
->bdev
, b
));
2067 static void bi_complete(struct bio
*bio
, int error
)
2069 complete((struct completion
*)bio
->bi_private
);
2072 static int submit_bio_wait(int rw
, struct bio
*bio
)
2074 struct completion event
;
2077 init_completion(&event
);
2078 bio
->bi_private
= &event
;
2079 bio
->bi_end_io
= bi_complete
;
2080 submit_bio(rw
, bio
);
2081 wait_for_completion(&event
);
2083 return test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
2086 static int narrow_write_error(struct r1bio
*r1_bio
, int i
)
2088 struct mddev
*mddev
= r1_bio
->mddev
;
2089 struct r1conf
*conf
= mddev
->private;
2090 struct md_rdev
*rdev
= conf
->mirrors
[i
].rdev
;
2092 struct bio_vec
*vec
;
2094 /* bio has the data to be written to device 'i' where
2095 * we just recently had a write error.
2096 * We repeatedly clone the bio and trim down to one block,
2097 * then try the write. Where the write fails we record
2099 * It is conceivable that the bio doesn't exactly align with
2100 * blocks. We must handle this somehow.
2102 * We currently own a reference on the rdev.
2108 int sect_to_write
= r1_bio
->sectors
;
2111 if (rdev
->badblocks
.shift
< 0)
2114 block_sectors
= 1 << rdev
->badblocks
.shift
;
2115 sector
= r1_bio
->sector
;
2116 sectors
= ((sector
+ block_sectors
)
2117 & ~(sector_t
)(block_sectors
- 1))
2120 if (test_bit(R1BIO_BehindIO
, &r1_bio
->state
)) {
2121 vcnt
= r1_bio
->behind_page_count
;
2122 vec
= r1_bio
->behind_bvecs
;
2124 while (vec
[idx
].bv_page
== NULL
)
2127 vcnt
= r1_bio
->master_bio
->bi_vcnt
;
2128 vec
= r1_bio
->master_bio
->bi_io_vec
;
2129 idx
= r1_bio
->master_bio
->bi_idx
;
2131 while (sect_to_write
) {
2133 if (sectors
> sect_to_write
)
2134 sectors
= sect_to_write
;
2135 /* Write at 'sector' for 'sectors'*/
2137 wbio
= bio_alloc_mddev(GFP_NOIO
, vcnt
, mddev
);
2138 memcpy(wbio
->bi_io_vec
, vec
, vcnt
* sizeof(struct bio_vec
));
2139 wbio
->bi_sector
= r1_bio
->sector
;
2140 wbio
->bi_rw
= WRITE
;
2141 wbio
->bi_vcnt
= vcnt
;
2142 wbio
->bi_size
= r1_bio
->sectors
<< 9;
2145 md_trim_bio(wbio
, sector
- r1_bio
->sector
, sectors
);
2146 wbio
->bi_sector
+= rdev
->data_offset
;
2147 wbio
->bi_bdev
= rdev
->bdev
;
2148 if (submit_bio_wait(WRITE
, wbio
) == 0)
2150 ok
= rdev_set_badblocks(rdev
, sector
,
2155 sect_to_write
-= sectors
;
2157 sectors
= block_sectors
;
2162 static void handle_sync_write_finished(struct r1conf
*conf
, struct r1bio
*r1_bio
)
2165 int s
= r1_bio
->sectors
;
2166 for (m
= 0; m
< conf
->raid_disks
* 2 ; m
++) {
2167 struct md_rdev
*rdev
= conf
->mirrors
[m
].rdev
;
2168 struct bio
*bio
= r1_bio
->bios
[m
];
2169 if (bio
->bi_end_io
== NULL
)
2171 if (test_bit(BIO_UPTODATE
, &bio
->bi_flags
) &&
2172 test_bit(R1BIO_MadeGood
, &r1_bio
->state
)) {
2173 rdev_clear_badblocks(rdev
, r1_bio
->sector
, s
, 0);
2175 if (!test_bit(BIO_UPTODATE
, &bio
->bi_flags
) &&
2176 test_bit(R1BIO_WriteError
, &r1_bio
->state
)) {
2177 if (!rdev_set_badblocks(rdev
, r1_bio
->sector
, s
, 0))
2178 md_error(conf
->mddev
, rdev
);
2182 md_done_sync(conf
->mddev
, s
, 1);
2185 static void handle_write_finished(struct r1conf
*conf
, struct r1bio
*r1_bio
)
2188 for (m
= 0; m
< conf
->raid_disks
* 2 ; m
++)
2189 if (r1_bio
->bios
[m
] == IO_MADE_GOOD
) {
2190 struct md_rdev
*rdev
= conf
->mirrors
[m
].rdev
;
2191 rdev_clear_badblocks(rdev
,
2193 r1_bio
->sectors
, 0);
2194 rdev_dec_pending(rdev
, conf
->mddev
);
2195 } else if (r1_bio
->bios
[m
] != NULL
) {
2196 /* This drive got a write error. We need to
2197 * narrow down and record precise write
2200 if (!narrow_write_error(r1_bio
, m
)) {
2201 md_error(conf
->mddev
,
2202 conf
->mirrors
[m
].rdev
);
2203 /* an I/O failed, we can't clear the bitmap */
2204 set_bit(R1BIO_Degraded
, &r1_bio
->state
);
2206 rdev_dec_pending(conf
->mirrors
[m
].rdev
,
2209 if (test_bit(R1BIO_WriteError
, &r1_bio
->state
))
2210 close_write(r1_bio
);
2211 raid_end_bio_io(r1_bio
);
2214 static void handle_read_error(struct r1conf
*conf
, struct r1bio
*r1_bio
)
2218 struct mddev
*mddev
= conf
->mddev
;
2220 char b
[BDEVNAME_SIZE
];
2221 struct md_rdev
*rdev
;
2223 clear_bit(R1BIO_ReadError
, &r1_bio
->state
);
2224 /* we got a read error. Maybe the drive is bad. Maybe just
2225 * the block and we can fix it.
2226 * We freeze all other IO, and try reading the block from
2227 * other devices. When we find one, we re-write
2228 * and check it that fixes the read error.
2229 * This is all done synchronously while the array is
2232 if (mddev
->ro
== 0) {
2234 fix_read_error(conf
, r1_bio
->read_disk
,
2235 r1_bio
->sector
, r1_bio
->sectors
);
2236 unfreeze_array(conf
);
2238 md_error(mddev
, conf
->mirrors
[r1_bio
->read_disk
].rdev
);
2239 rdev_dec_pending(conf
->mirrors
[r1_bio
->read_disk
].rdev
, conf
->mddev
);
2241 bio
= r1_bio
->bios
[r1_bio
->read_disk
];
2242 bdevname(bio
->bi_bdev
, b
);
2244 disk
= read_balance(conf
, r1_bio
, &max_sectors
);
2246 printk(KERN_ALERT
"md/raid1:%s: %s: unrecoverable I/O"
2247 " read error for block %llu\n",
2248 mdname(mddev
), b
, (unsigned long long)r1_bio
->sector
);
2249 raid_end_bio_io(r1_bio
);
2251 const unsigned long do_sync
2252 = r1_bio
->master_bio
->bi_rw
& REQ_SYNC
;
2254 r1_bio
->bios
[r1_bio
->read_disk
] =
2255 mddev
->ro
? IO_BLOCKED
: NULL
;
2258 r1_bio
->read_disk
= disk
;
2259 bio
= bio_clone_mddev(r1_bio
->master_bio
, GFP_NOIO
, mddev
);
2260 md_trim_bio(bio
, r1_bio
->sector
- bio
->bi_sector
, max_sectors
);
2261 r1_bio
->bios
[r1_bio
->read_disk
] = bio
;
2262 rdev
= conf
->mirrors
[disk
].rdev
;
2263 printk_ratelimited(KERN_ERR
2264 "md/raid1:%s: redirecting sector %llu"
2265 " to other mirror: %s\n",
2267 (unsigned long long)r1_bio
->sector
,
2268 bdevname(rdev
->bdev
, b
));
2269 bio
->bi_sector
= r1_bio
->sector
+ rdev
->data_offset
;
2270 bio
->bi_bdev
= rdev
->bdev
;
2271 bio
->bi_end_io
= raid1_end_read_request
;
2272 bio
->bi_rw
= READ
| do_sync
;
2273 bio
->bi_private
= r1_bio
;
2274 if (max_sectors
< r1_bio
->sectors
) {
2275 /* Drat - have to split this up more */
2276 struct bio
*mbio
= r1_bio
->master_bio
;
2277 int sectors_handled
= (r1_bio
->sector
+ max_sectors
2279 r1_bio
->sectors
= max_sectors
;
2280 spin_lock_irq(&conf
->device_lock
);
2281 if (mbio
->bi_phys_segments
== 0)
2282 mbio
->bi_phys_segments
= 2;
2284 mbio
->bi_phys_segments
++;
2285 spin_unlock_irq(&conf
->device_lock
);
2286 generic_make_request(bio
);
2289 r1_bio
= mempool_alloc(conf
->r1bio_pool
, GFP_NOIO
);
2291 r1_bio
->master_bio
= mbio
;
2292 r1_bio
->sectors
= (mbio
->bi_size
>> 9)
2295 set_bit(R1BIO_ReadError
, &r1_bio
->state
);
2296 r1_bio
->mddev
= mddev
;
2297 r1_bio
->sector
= mbio
->bi_sector
+ sectors_handled
;
2301 generic_make_request(bio
);
2305 static void raid1d(struct md_thread
*thread
)
2307 struct mddev
*mddev
= thread
->mddev
;
2308 struct r1bio
*r1_bio
;
2309 unsigned long flags
;
2310 struct r1conf
*conf
= mddev
->private;
2311 struct list_head
*head
= &conf
->retry_list
;
2312 struct blk_plug plug
;
2314 md_check_recovery(mddev
);
2316 blk_start_plug(&plug
);
2319 flush_pending_writes(conf
);
2321 spin_lock_irqsave(&conf
->device_lock
, flags
);
2322 if (list_empty(head
)) {
2323 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
2326 r1_bio
= list_entry(head
->prev
, struct r1bio
, retry_list
);
2327 list_del(head
->prev
);
2329 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
2331 mddev
= r1_bio
->mddev
;
2332 conf
= mddev
->private;
2333 if (test_bit(R1BIO_IsSync
, &r1_bio
->state
)) {
2334 if (test_bit(R1BIO_MadeGood
, &r1_bio
->state
) ||
2335 test_bit(R1BIO_WriteError
, &r1_bio
->state
))
2336 handle_sync_write_finished(conf
, r1_bio
);
2338 sync_request_write(mddev
, r1_bio
);
2339 } else if (test_bit(R1BIO_MadeGood
, &r1_bio
->state
) ||
2340 test_bit(R1BIO_WriteError
, &r1_bio
->state
))
2341 handle_write_finished(conf
, r1_bio
);
2342 else if (test_bit(R1BIO_ReadError
, &r1_bio
->state
))
2343 handle_read_error(conf
, r1_bio
);
2345 /* just a partial read to be scheduled from separate
2348 generic_make_request(r1_bio
->bios
[r1_bio
->read_disk
]);
2351 if (mddev
->flags
& ~(1<<MD_CHANGE_PENDING
))
2352 md_check_recovery(mddev
);
2354 blk_finish_plug(&plug
);
2358 static int init_resync(struct r1conf
*conf
)
2362 buffs
= RESYNC_WINDOW
/ RESYNC_BLOCK_SIZE
;
2363 BUG_ON(conf
->r1buf_pool
);
2364 conf
->r1buf_pool
= mempool_create(buffs
, r1buf_pool_alloc
, r1buf_pool_free
,
2366 if (!conf
->r1buf_pool
)
2368 conf
->next_resync
= 0;
2373 * perform a "sync" on one "block"
2375 * We need to make sure that no normal I/O request - particularly write
2376 * requests - conflict with active sync requests.
2378 * This is achieved by tracking pending requests and a 'barrier' concept
2379 * that can be installed to exclude normal IO requests.
2382 static sector_t
sync_request(struct mddev
*mddev
, sector_t sector_nr
, int *skipped
, int go_faster
)
2384 struct r1conf
*conf
= mddev
->private;
2385 struct r1bio
*r1_bio
;
2387 sector_t max_sector
, nr_sectors
;
2391 int write_targets
= 0, read_targets
= 0;
2392 sector_t sync_blocks
;
2393 int still_degraded
= 0;
2394 int good_sectors
= RESYNC_SECTORS
;
2395 int min_bad
= 0; /* number of sectors that are bad in all devices */
2397 if (!conf
->r1buf_pool
)
2398 if (init_resync(conf
))
2401 max_sector
= mddev
->dev_sectors
;
2402 if (sector_nr
>= max_sector
) {
2403 /* If we aborted, we need to abort the
2404 * sync on the 'current' bitmap chunk (there will
2405 * only be one in raid1 resync.
2406 * We can find the current addess in mddev->curr_resync
2408 if (mddev
->curr_resync
< max_sector
) /* aborted */
2409 bitmap_end_sync(mddev
->bitmap
, mddev
->curr_resync
,
2411 else /* completed sync */
2414 bitmap_close_sync(mddev
->bitmap
);
2419 if (mddev
->bitmap
== NULL
&&
2420 mddev
->recovery_cp
== MaxSector
&&
2421 !test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
) &&
2422 conf
->fullsync
== 0) {
2424 return max_sector
- sector_nr
;
2426 /* before building a request, check if we can skip these blocks..
2427 * This call the bitmap_start_sync doesn't actually record anything
2429 if (!bitmap_start_sync(mddev
->bitmap
, sector_nr
, &sync_blocks
, 1) &&
2430 !conf
->fullsync
&& !test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
)) {
2431 /* We can skip this block, and probably several more */
2436 * If there is non-resync activity waiting for a turn,
2437 * and resync is going fast enough,
2438 * then let it though before starting on this new sync request.
2440 if (!go_faster
&& conf
->nr_waiting
)
2441 msleep_interruptible(1000);
2443 bitmap_cond_end_sync(mddev
->bitmap
, sector_nr
);
2444 r1_bio
= mempool_alloc(conf
->r1buf_pool
, GFP_NOIO
);
2445 raise_barrier(conf
);
2447 conf
->next_resync
= sector_nr
;
2451 * If we get a correctably read error during resync or recovery,
2452 * we might want to read from a different device. So we
2453 * flag all drives that could conceivably be read from for READ,
2454 * and any others (which will be non-In_sync devices) for WRITE.
2455 * If a read fails, we try reading from something else for which READ
2459 r1_bio
->mddev
= mddev
;
2460 r1_bio
->sector
= sector_nr
;
2462 set_bit(R1BIO_IsSync
, &r1_bio
->state
);
2464 for (i
= 0; i
< conf
->raid_disks
* 2; i
++) {
2465 struct md_rdev
*rdev
;
2466 bio
= r1_bio
->bios
[i
];
2468 /* take from bio_init */
2469 bio
->bi_next
= NULL
;
2470 bio
->bi_flags
&= ~(BIO_POOL_MASK
-1);
2471 bio
->bi_flags
|= 1 << BIO_UPTODATE
;
2475 bio
->bi_phys_segments
= 0;
2477 bio
->bi_end_io
= NULL
;
2478 bio
->bi_private
= NULL
;
2480 rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
2482 test_bit(Faulty
, &rdev
->flags
)) {
2483 if (i
< conf
->raid_disks
)
2485 } else if (!test_bit(In_sync
, &rdev
->flags
)) {
2487 bio
->bi_end_io
= end_sync_write
;
2490 /* may need to read from here */
2491 sector_t first_bad
= MaxSector
;
2494 if (is_badblock(rdev
, sector_nr
, good_sectors
,
2495 &first_bad
, &bad_sectors
)) {
2496 if (first_bad
> sector_nr
)
2497 good_sectors
= first_bad
- sector_nr
;
2499 bad_sectors
-= (sector_nr
- first_bad
);
2501 min_bad
> bad_sectors
)
2502 min_bad
= bad_sectors
;
2505 if (sector_nr
< first_bad
) {
2506 if (test_bit(WriteMostly
, &rdev
->flags
)) {
2514 bio
->bi_end_io
= end_sync_read
;
2516 } else if (!test_bit(WriteErrorSeen
, &rdev
->flags
) &&
2517 test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
) &&
2518 !test_bit(MD_RECOVERY_CHECK
, &mddev
->recovery
)) {
2520 * The device is suitable for reading (InSync),
2521 * but has bad block(s) here. Let's try to correct them,
2522 * if we are doing resync or repair. Otherwise, leave
2523 * this device alone for this sync request.
2526 bio
->bi_end_io
= end_sync_write
;
2530 if (bio
->bi_end_io
) {
2531 atomic_inc(&rdev
->nr_pending
);
2532 bio
->bi_sector
= sector_nr
+ rdev
->data_offset
;
2533 bio
->bi_bdev
= rdev
->bdev
;
2534 bio
->bi_private
= r1_bio
;
2540 r1_bio
->read_disk
= disk
;
2542 if (read_targets
== 0 && min_bad
> 0) {
2543 /* These sectors are bad on all InSync devices, so we
2544 * need to mark them bad on all write targets
2547 for (i
= 0 ; i
< conf
->raid_disks
* 2 ; i
++)
2548 if (r1_bio
->bios
[i
]->bi_end_io
== end_sync_write
) {
2549 struct md_rdev
*rdev
= conf
->mirrors
[i
].rdev
;
2550 ok
= rdev_set_badblocks(rdev
, sector_nr
,
2554 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
2559 /* Cannot record the badblocks, so need to
2561 * If there are multiple read targets, could just
2562 * fail the really bad ones ???
2564 conf
->recovery_disabled
= mddev
->recovery_disabled
;
2565 set_bit(MD_RECOVERY_INTR
, &mddev
->recovery
);
2571 if (min_bad
> 0 && min_bad
< good_sectors
) {
2572 /* only resync enough to reach the next bad->good
2574 good_sectors
= min_bad
;
2577 if (test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
) && read_targets
> 0)
2578 /* extra read targets are also write targets */
2579 write_targets
+= read_targets
-1;
2581 if (write_targets
== 0 || read_targets
== 0) {
2582 /* There is nowhere to write, so all non-sync
2583 * drives must be failed - so we are finished
2587 max_sector
= sector_nr
+ min_bad
;
2588 rv
= max_sector
- sector_nr
;
2594 if (max_sector
> mddev
->resync_max
)
2595 max_sector
= mddev
->resync_max
; /* Don't do IO beyond here */
2596 if (max_sector
> sector_nr
+ good_sectors
)
2597 max_sector
= sector_nr
+ good_sectors
;
2602 int len
= PAGE_SIZE
;
2603 if (sector_nr
+ (len
>>9) > max_sector
)
2604 len
= (max_sector
- sector_nr
) << 9;
2607 if (sync_blocks
== 0) {
2608 if (!bitmap_start_sync(mddev
->bitmap
, sector_nr
,
2609 &sync_blocks
, still_degraded
) &&
2611 !test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
))
2613 BUG_ON(sync_blocks
< (PAGE_SIZE
>>9));
2614 if ((len
>> 9) > sync_blocks
)
2615 len
= sync_blocks
<<9;
2618 for (i
= 0 ; i
< conf
->raid_disks
* 2; i
++) {
2619 bio
= r1_bio
->bios
[i
];
2620 if (bio
->bi_end_io
) {
2621 page
= bio
->bi_io_vec
[bio
->bi_vcnt
].bv_page
;
2622 if (bio_add_page(bio
, page
, len
, 0) == 0) {
2624 bio
->bi_io_vec
[bio
->bi_vcnt
].bv_page
= page
;
2627 bio
= r1_bio
->bios
[i
];
2628 if (bio
->bi_end_io
==NULL
)
2630 /* remove last page from this bio */
2632 bio
->bi_size
-= len
;
2633 bio
->bi_flags
&= ~(1<< BIO_SEG_VALID
);
2639 nr_sectors
+= len
>>9;
2640 sector_nr
+= len
>>9;
2641 sync_blocks
-= (len
>>9);
2642 } while (r1_bio
->bios
[disk
]->bi_vcnt
< RESYNC_PAGES
);
2644 r1_bio
->sectors
= nr_sectors
;
2646 /* For a user-requested sync, we read all readable devices and do a
2649 if (test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
)) {
2650 atomic_set(&r1_bio
->remaining
, read_targets
);
2651 for (i
= 0; i
< conf
->raid_disks
* 2 && read_targets
; i
++) {
2652 bio
= r1_bio
->bios
[i
];
2653 if (bio
->bi_end_io
== end_sync_read
) {
2655 md_sync_acct(bio
->bi_bdev
, nr_sectors
);
2656 generic_make_request(bio
);
2660 atomic_set(&r1_bio
->remaining
, 1);
2661 bio
= r1_bio
->bios
[r1_bio
->read_disk
];
2662 md_sync_acct(bio
->bi_bdev
, nr_sectors
);
2663 generic_make_request(bio
);
2669 static sector_t
raid1_size(struct mddev
*mddev
, sector_t sectors
, int raid_disks
)
2674 return mddev
->dev_sectors
;
2677 static struct r1conf
*setup_conf(struct mddev
*mddev
)
2679 struct r1conf
*conf
;
2681 struct raid1_info
*disk
;
2682 struct md_rdev
*rdev
;
2685 conf
= kzalloc(sizeof(struct r1conf
), GFP_KERNEL
);
2689 conf
->mirrors
= kzalloc(sizeof(struct raid1_info
)
2690 * mddev
->raid_disks
* 2,
2695 conf
->tmppage
= alloc_page(GFP_KERNEL
);
2699 conf
->poolinfo
= kzalloc(sizeof(*conf
->poolinfo
), GFP_KERNEL
);
2700 if (!conf
->poolinfo
)
2702 conf
->poolinfo
->raid_disks
= mddev
->raid_disks
* 2;
2703 conf
->r1bio_pool
= mempool_create(NR_RAID1_BIOS
, r1bio_pool_alloc
,
2706 if (!conf
->r1bio_pool
)
2709 conf
->poolinfo
->mddev
= mddev
;
2712 spin_lock_init(&conf
->device_lock
);
2713 rdev_for_each(rdev
, mddev
) {
2714 struct request_queue
*q
;
2715 int disk_idx
= rdev
->raid_disk
;
2716 if (disk_idx
>= mddev
->raid_disks
2719 if (test_bit(Replacement
, &rdev
->flags
))
2720 disk
= conf
->mirrors
+ mddev
->raid_disks
+ disk_idx
;
2722 disk
= conf
->mirrors
+ disk_idx
;
2727 q
= bdev_get_queue(rdev
->bdev
);
2728 if (q
->merge_bvec_fn
)
2729 mddev
->merge_check_needed
= 1;
2731 disk
->head_position
= 0;
2732 disk
->seq_start
= MaxSector
;
2734 conf
->raid_disks
= mddev
->raid_disks
;
2735 conf
->mddev
= mddev
;
2736 INIT_LIST_HEAD(&conf
->retry_list
);
2738 spin_lock_init(&conf
->resync_lock
);
2739 init_waitqueue_head(&conf
->wait_barrier
);
2741 bio_list_init(&conf
->pending_bio_list
);
2742 conf
->pending_count
= 0;
2743 conf
->recovery_disabled
= mddev
->recovery_disabled
- 1;
2746 for (i
= 0; i
< conf
->raid_disks
* 2; i
++) {
2748 disk
= conf
->mirrors
+ i
;
2750 if (i
< conf
->raid_disks
&&
2751 disk
[conf
->raid_disks
].rdev
) {
2752 /* This slot has a replacement. */
2754 /* No original, just make the replacement
2755 * a recovering spare
2758 disk
[conf
->raid_disks
].rdev
;
2759 disk
[conf
->raid_disks
].rdev
= NULL
;
2760 } else if (!test_bit(In_sync
, &disk
->rdev
->flags
))
2761 /* Original is not in_sync - bad */
2766 !test_bit(In_sync
, &disk
->rdev
->flags
)) {
2767 disk
->head_position
= 0;
2769 (disk
->rdev
->saved_raid_disk
< 0))
2775 conf
->thread
= md_register_thread(raid1d
, mddev
, "raid1");
2776 if (!conf
->thread
) {
2778 "md/raid1:%s: couldn't allocate thread\n",
2787 if (conf
->r1bio_pool
)
2788 mempool_destroy(conf
->r1bio_pool
);
2789 kfree(conf
->mirrors
);
2790 safe_put_page(conf
->tmppage
);
2791 kfree(conf
->poolinfo
);
2794 return ERR_PTR(err
);
2797 static int stop(struct mddev
*mddev
);
2798 static int run(struct mddev
*mddev
)
2800 struct r1conf
*conf
;
2802 struct md_rdev
*rdev
;
2804 bool discard_supported
= false;
2806 if (mddev
->level
!= 1) {
2807 printk(KERN_ERR
"md/raid1:%s: raid level not set to mirroring (%d)\n",
2808 mdname(mddev
), mddev
->level
);
2811 if (mddev
->reshape_position
!= MaxSector
) {
2812 printk(KERN_ERR
"md/raid1:%s: reshape_position set but not supported\n",
2817 * copy the already verified devices into our private RAID1
2818 * bookkeeping area. [whatever we allocate in run(),
2819 * should be freed in stop()]
2821 if (mddev
->private == NULL
)
2822 conf
= setup_conf(mddev
);
2824 conf
= mddev
->private;
2827 return PTR_ERR(conf
);
2830 blk_queue_max_write_same_sectors(mddev
->queue
,
2831 mddev
->chunk_sectors
);
2832 rdev_for_each(rdev
, mddev
) {
2833 if (!mddev
->gendisk
)
2835 disk_stack_limits(mddev
->gendisk
, rdev
->bdev
,
2836 rdev
->data_offset
<< 9);
2837 if (blk_queue_discard(bdev_get_queue(rdev
->bdev
)))
2838 discard_supported
= true;
2841 mddev
->degraded
= 0;
2842 for (i
=0; i
< conf
->raid_disks
; i
++)
2843 if (conf
->mirrors
[i
].rdev
== NULL
||
2844 !test_bit(In_sync
, &conf
->mirrors
[i
].rdev
->flags
) ||
2845 test_bit(Faulty
, &conf
->mirrors
[i
].rdev
->flags
))
2848 if (conf
->raid_disks
- mddev
->degraded
== 1)
2849 mddev
->recovery_cp
= MaxSector
;
2851 if (mddev
->recovery_cp
!= MaxSector
)
2852 printk(KERN_NOTICE
"md/raid1:%s: not clean"
2853 " -- starting background reconstruction\n",
2856 "md/raid1:%s: active with %d out of %d mirrors\n",
2857 mdname(mddev
), mddev
->raid_disks
- mddev
->degraded
,
2861 * Ok, everything is just fine now
2863 mddev
->thread
= conf
->thread
;
2864 conf
->thread
= NULL
;
2865 mddev
->private = conf
;
2867 md_set_array_sectors(mddev
, raid1_size(mddev
, 0, 0));
2870 mddev
->queue
->backing_dev_info
.congested_fn
= raid1_congested
;
2871 mddev
->queue
->backing_dev_info
.congested_data
= mddev
;
2872 blk_queue_merge_bvec(mddev
->queue
, raid1_mergeable_bvec
);
2874 if (discard_supported
)
2875 queue_flag_set_unlocked(QUEUE_FLAG_DISCARD
,
2878 queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD
,
2882 ret
= md_integrity_register(mddev
);
2888 static int stop(struct mddev
*mddev
)
2890 struct r1conf
*conf
= mddev
->private;
2891 struct bitmap
*bitmap
= mddev
->bitmap
;
2893 /* wait for behind writes to complete */
2894 if (bitmap
&& atomic_read(&bitmap
->behind_writes
) > 0) {
2895 printk(KERN_INFO
"md/raid1:%s: behind writes in progress - waiting to stop.\n",
2897 /* need to kick something here to make sure I/O goes? */
2898 wait_event(bitmap
->behind_wait
,
2899 atomic_read(&bitmap
->behind_writes
) == 0);
2902 raise_barrier(conf
);
2903 lower_barrier(conf
);
2905 md_unregister_thread(&mddev
->thread
);
2906 if (conf
->r1bio_pool
)
2907 mempool_destroy(conf
->r1bio_pool
);
2908 kfree(conf
->mirrors
);
2909 safe_put_page(conf
->tmppage
);
2910 kfree(conf
->poolinfo
);
2912 mddev
->private = NULL
;
2916 static int raid1_resize(struct mddev
*mddev
, sector_t sectors
)
2918 /* no resync is happening, and there is enough space
2919 * on all devices, so we can resize.
2920 * We need to make sure resync covers any new space.
2921 * If the array is shrinking we should possibly wait until
2922 * any io in the removed space completes, but it hardly seems
2925 sector_t newsize
= raid1_size(mddev
, sectors
, 0);
2926 if (mddev
->external_size
&&
2927 mddev
->array_sectors
> newsize
)
2929 if (mddev
->bitmap
) {
2930 int ret
= bitmap_resize(mddev
->bitmap
, newsize
, 0, 0);
2934 md_set_array_sectors(mddev
, newsize
);
2935 set_capacity(mddev
->gendisk
, mddev
->array_sectors
);
2936 revalidate_disk(mddev
->gendisk
);
2937 if (sectors
> mddev
->dev_sectors
&&
2938 mddev
->recovery_cp
> mddev
->dev_sectors
) {
2939 mddev
->recovery_cp
= mddev
->dev_sectors
;
2940 set_bit(MD_RECOVERY_NEEDED
, &mddev
->recovery
);
2942 mddev
->dev_sectors
= sectors
;
2943 mddev
->resync_max_sectors
= sectors
;
2947 static int raid1_reshape(struct mddev
*mddev
)
2950 * 1/ resize the r1bio_pool
2951 * 2/ resize conf->mirrors
2953 * We allocate a new r1bio_pool if we can.
2954 * Then raise a device barrier and wait until all IO stops.
2955 * Then resize conf->mirrors and swap in the new r1bio pool.
2957 * At the same time, we "pack" the devices so that all the missing
2958 * devices have the higher raid_disk numbers.
2960 mempool_t
*newpool
, *oldpool
;
2961 struct pool_info
*newpoolinfo
;
2962 struct raid1_info
*newmirrors
;
2963 struct r1conf
*conf
= mddev
->private;
2964 int cnt
, raid_disks
;
2965 unsigned long flags
;
2968 /* Cannot change chunk_size, layout, or level */
2969 if (mddev
->chunk_sectors
!= mddev
->new_chunk_sectors
||
2970 mddev
->layout
!= mddev
->new_layout
||
2971 mddev
->level
!= mddev
->new_level
) {
2972 mddev
->new_chunk_sectors
= mddev
->chunk_sectors
;
2973 mddev
->new_layout
= mddev
->layout
;
2974 mddev
->new_level
= mddev
->level
;
2978 err
= md_allow_write(mddev
);
2982 raid_disks
= mddev
->raid_disks
+ mddev
->delta_disks
;
2984 if (raid_disks
< conf
->raid_disks
) {
2986 for (d
= 0; d
< conf
->raid_disks
; d
++)
2987 if (conf
->mirrors
[d
].rdev
)
2989 if (cnt
> raid_disks
)
2993 newpoolinfo
= kmalloc(sizeof(*newpoolinfo
), GFP_KERNEL
);
2996 newpoolinfo
->mddev
= mddev
;
2997 newpoolinfo
->raid_disks
= raid_disks
* 2;
2999 newpool
= mempool_create(NR_RAID1_BIOS
, r1bio_pool_alloc
,
3000 r1bio_pool_free
, newpoolinfo
);
3005 newmirrors
= kzalloc(sizeof(struct raid1_info
) * raid_disks
* 2,
3009 mempool_destroy(newpool
);
3013 raise_barrier(conf
);
3015 /* ok, everything is stopped */
3016 oldpool
= conf
->r1bio_pool
;
3017 conf
->r1bio_pool
= newpool
;
3019 for (d
= d2
= 0; d
< conf
->raid_disks
; d
++) {
3020 struct md_rdev
*rdev
= conf
->mirrors
[d
].rdev
;
3021 if (rdev
&& rdev
->raid_disk
!= d2
) {
3022 sysfs_unlink_rdev(mddev
, rdev
);
3023 rdev
->raid_disk
= d2
;
3024 sysfs_unlink_rdev(mddev
, rdev
);
3025 if (sysfs_link_rdev(mddev
, rdev
))
3027 "md/raid1:%s: cannot register rd%d\n",
3028 mdname(mddev
), rdev
->raid_disk
);
3031 newmirrors
[d2
++].rdev
= rdev
;
3033 kfree(conf
->mirrors
);
3034 conf
->mirrors
= newmirrors
;
3035 kfree(conf
->poolinfo
);
3036 conf
->poolinfo
= newpoolinfo
;
3038 spin_lock_irqsave(&conf
->device_lock
, flags
);
3039 mddev
->degraded
+= (raid_disks
- conf
->raid_disks
);
3040 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
3041 conf
->raid_disks
= mddev
->raid_disks
= raid_disks
;
3042 mddev
->delta_disks
= 0;
3044 lower_barrier(conf
);
3046 set_bit(MD_RECOVERY_NEEDED
, &mddev
->recovery
);
3047 md_wakeup_thread(mddev
->thread
);
3049 mempool_destroy(oldpool
);
3053 static void raid1_quiesce(struct mddev
*mddev
, int state
)
3055 struct r1conf
*conf
= mddev
->private;
3058 case 2: /* wake for suspend */
3059 wake_up(&conf
->wait_barrier
);
3062 raise_barrier(conf
);
3065 lower_barrier(conf
);
3070 static void *raid1_takeover(struct mddev
*mddev
)
3072 /* raid1 can take over:
3073 * raid5 with 2 devices, any layout or chunk size
3075 if (mddev
->level
== 5 && mddev
->raid_disks
== 2) {
3076 struct r1conf
*conf
;
3077 mddev
->new_level
= 1;
3078 mddev
->new_layout
= 0;
3079 mddev
->new_chunk_sectors
= 0;
3080 conf
= setup_conf(mddev
);
3085 return ERR_PTR(-EINVAL
);
3088 static struct md_personality raid1_personality
=
3092 .owner
= THIS_MODULE
,
3093 .make_request
= make_request
,
3097 .error_handler
= error
,
3098 .hot_add_disk
= raid1_add_disk
,
3099 .hot_remove_disk
= raid1_remove_disk
,
3100 .spare_active
= raid1_spare_active
,
3101 .sync_request
= sync_request
,
3102 .resize
= raid1_resize
,
3104 .check_reshape
= raid1_reshape
,
3105 .quiesce
= raid1_quiesce
,
3106 .takeover
= raid1_takeover
,
3109 static int __init
raid_init(void)
3111 return register_md_personality(&raid1_personality
);
3114 static void raid_exit(void)
3116 unregister_md_personality(&raid1_personality
);
3119 module_init(raid_init
);
3120 module_exit(raid_exit
);
3121 MODULE_LICENSE("GPL");
3122 MODULE_DESCRIPTION("RAID1 (mirroring) personality for MD");
3123 MODULE_ALIAS("md-personality-3"); /* RAID1 */
3124 MODULE_ALIAS("md-raid1");
3125 MODULE_ALIAS("md-level-1");
3127 module_param(max_queued_requests
, int, S_IRUGO
|S_IWUSR
);