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/seq_file.h>
44 #define PRINTK(x...) printk(x)
50 * Number of guaranteed r1bios in case of extreme VM load:
52 #define NR_RAID1_BIOS 256
55 static void unplug_slaves(mddev_t
*mddev
);
57 static void allow_barrier(conf_t
*conf
);
58 static void lower_barrier(conf_t
*conf
);
60 static void * r1bio_pool_alloc(gfp_t gfp_flags
, void *data
)
62 struct pool_info
*pi
= data
;
64 int size
= offsetof(r1bio_t
, bios
[pi
->raid_disks
]);
66 /* allocate a r1bio with room for raid_disks entries in the bios array */
67 r1_bio
= kzalloc(size
, gfp_flags
);
68 if (!r1_bio
&& pi
->mddev
)
69 unplug_slaves(pi
->mddev
);
74 static void r1bio_pool_free(void *r1_bio
, void *data
)
79 #define RESYNC_BLOCK_SIZE (64*1024)
80 //#define RESYNC_BLOCK_SIZE PAGE_SIZE
81 #define RESYNC_SECTORS (RESYNC_BLOCK_SIZE >> 9)
82 #define RESYNC_PAGES ((RESYNC_BLOCK_SIZE + PAGE_SIZE-1) / PAGE_SIZE)
83 #define RESYNC_WINDOW (2048*1024)
85 static void * r1buf_pool_alloc(gfp_t gfp_flags
, void *data
)
87 struct pool_info
*pi
= data
;
93 r1_bio
= r1bio_pool_alloc(gfp_flags
, pi
);
95 unplug_slaves(pi
->mddev
);
100 * Allocate bios : 1 for reading, n-1 for writing
102 for (j
= pi
->raid_disks
; j
-- ; ) {
103 bio
= bio_alloc(gfp_flags
, RESYNC_PAGES
);
106 r1_bio
->bios
[j
] = bio
;
109 * Allocate RESYNC_PAGES data pages and attach them to
111 * If this is a user-requested check/repair, allocate
112 * RESYNC_PAGES for each bio.
114 if (test_bit(MD_RECOVERY_REQUESTED
, &pi
->mddev
->recovery
))
119 bio
= r1_bio
->bios
[j
];
120 for (i
= 0; i
< RESYNC_PAGES
; i
++) {
121 page
= alloc_page(gfp_flags
);
125 bio
->bi_io_vec
[i
].bv_page
= page
;
129 /* If not user-requests, copy the page pointers to all bios */
130 if (!test_bit(MD_RECOVERY_REQUESTED
, &pi
->mddev
->recovery
)) {
131 for (i
=0; i
<RESYNC_PAGES
; i
++)
132 for (j
=1; j
<pi
->raid_disks
; j
++)
133 r1_bio
->bios
[j
]->bi_io_vec
[i
].bv_page
=
134 r1_bio
->bios
[0]->bi_io_vec
[i
].bv_page
;
137 r1_bio
->master_bio
= NULL
;
142 for (j
=0 ; j
< pi
->raid_disks
; j
++)
143 for (i
=0; i
< r1_bio
->bios
[j
]->bi_vcnt
; i
++)
144 put_page(r1_bio
->bios
[j
]->bi_io_vec
[i
].bv_page
);
147 while ( ++j
< pi
->raid_disks
)
148 bio_put(r1_bio
->bios
[j
]);
149 r1bio_pool_free(r1_bio
, data
);
153 static void r1buf_pool_free(void *__r1_bio
, void *data
)
155 struct pool_info
*pi
= data
;
157 r1bio_t
*r1bio
= __r1_bio
;
159 for (i
= 0; i
< RESYNC_PAGES
; i
++)
160 for (j
= pi
->raid_disks
; j
-- ;) {
162 r1bio
->bios
[j
]->bi_io_vec
[i
].bv_page
!=
163 r1bio
->bios
[0]->bi_io_vec
[i
].bv_page
)
164 safe_put_page(r1bio
->bios
[j
]->bi_io_vec
[i
].bv_page
);
166 for (i
=0 ; i
< pi
->raid_disks
; i
++)
167 bio_put(r1bio
->bios
[i
]);
169 r1bio_pool_free(r1bio
, data
);
172 static void put_all_bios(conf_t
*conf
, r1bio_t
*r1_bio
)
176 for (i
= 0; i
< conf
->raid_disks
; i
++) {
177 struct bio
**bio
= r1_bio
->bios
+ i
;
178 if (*bio
&& *bio
!= IO_BLOCKED
)
184 static void free_r1bio(r1bio_t
*r1_bio
)
186 conf_t
*conf
= r1_bio
->mddev
->private;
189 * Wake up any possible resync thread that waits for the device
194 put_all_bios(conf
, r1_bio
);
195 mempool_free(r1_bio
, conf
->r1bio_pool
);
198 static void put_buf(r1bio_t
*r1_bio
)
200 conf_t
*conf
= r1_bio
->mddev
->private;
203 for (i
=0; i
<conf
->raid_disks
; i
++) {
204 struct bio
*bio
= r1_bio
->bios
[i
];
206 rdev_dec_pending(conf
->mirrors
[i
].rdev
, r1_bio
->mddev
);
209 mempool_free(r1_bio
, conf
->r1buf_pool
);
214 static void reschedule_retry(r1bio_t
*r1_bio
)
217 mddev_t
*mddev
= r1_bio
->mddev
;
218 conf_t
*conf
= mddev
->private;
220 spin_lock_irqsave(&conf
->device_lock
, flags
);
221 list_add(&r1_bio
->retry_list
, &conf
->retry_list
);
223 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
225 wake_up(&conf
->wait_barrier
);
226 md_wakeup_thread(mddev
->thread
);
230 * raid_end_bio_io() is called when we have finished servicing a mirrored
231 * operation and are ready to return a success/failure code to the buffer
234 static void raid_end_bio_io(r1bio_t
*r1_bio
)
236 struct bio
*bio
= r1_bio
->master_bio
;
238 /* if nobody has done the final endio yet, do it now */
239 if (!test_and_set_bit(R1BIO_Returned
, &r1_bio
->state
)) {
240 PRINTK(KERN_DEBUG
"raid1: sync end %s on sectors %llu-%llu\n",
241 (bio_data_dir(bio
) == WRITE
) ? "write" : "read",
242 (unsigned long long) bio
->bi_sector
,
243 (unsigned long long) bio
->bi_sector
+
244 (bio
->bi_size
>> 9) - 1);
247 test_bit(R1BIO_Uptodate
, &r1_bio
->state
) ? 0 : -EIO
);
253 * Update disk head position estimator based on IRQ completion info.
255 static inline void update_head_pos(int disk
, r1bio_t
*r1_bio
)
257 conf_t
*conf
= r1_bio
->mddev
->private;
259 conf
->mirrors
[disk
].head_position
=
260 r1_bio
->sector
+ (r1_bio
->sectors
);
263 static void raid1_end_read_request(struct bio
*bio
, int error
)
265 int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
266 r1bio_t
*r1_bio
= bio
->bi_private
;
268 conf_t
*conf
= r1_bio
->mddev
->private;
270 mirror
= r1_bio
->read_disk
;
272 * this branch is our 'one mirror IO has finished' event handler:
274 update_head_pos(mirror
, r1_bio
);
277 set_bit(R1BIO_Uptodate
, &r1_bio
->state
);
279 /* If all other devices have failed, we want to return
280 * the error upwards rather than fail the last device.
281 * Here we redefine "uptodate" to mean "Don't want to retry"
284 spin_lock_irqsave(&conf
->device_lock
, flags
);
285 if (r1_bio
->mddev
->degraded
== conf
->raid_disks
||
286 (r1_bio
->mddev
->degraded
== conf
->raid_disks
-1 &&
287 !test_bit(Faulty
, &conf
->mirrors
[mirror
].rdev
->flags
)))
289 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
293 raid_end_bio_io(r1_bio
);
298 char b
[BDEVNAME_SIZE
];
299 if (printk_ratelimit())
300 printk(KERN_ERR
"md/raid1:%s: %s: rescheduling sector %llu\n",
302 bdevname(conf
->mirrors
[mirror
].rdev
->bdev
,b
), (unsigned long long)r1_bio
->sector
);
303 reschedule_retry(r1_bio
);
306 rdev_dec_pending(conf
->mirrors
[mirror
].rdev
, conf
->mddev
);
309 static void raid1_end_write_request(struct bio
*bio
, int error
)
311 int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
312 r1bio_t
*r1_bio
= bio
->bi_private
;
313 int mirror
, behind
= test_bit(R1BIO_BehindIO
, &r1_bio
->state
);
314 conf_t
*conf
= r1_bio
->mddev
->private;
315 struct bio
*to_put
= NULL
;
318 for (mirror
= 0; mirror
< conf
->raid_disks
; mirror
++)
319 if (r1_bio
->bios
[mirror
] == bio
)
322 if (error
== -EOPNOTSUPP
&& test_bit(R1BIO_Barrier
, &r1_bio
->state
)) {
323 set_bit(BarriersNotsupp
, &conf
->mirrors
[mirror
].rdev
->flags
);
324 set_bit(R1BIO_BarrierRetry
, &r1_bio
->state
);
325 r1_bio
->mddev
->barriers_work
= 0;
326 /* Don't rdev_dec_pending in this branch - keep it for the retry */
329 * this branch is our 'one mirror IO has finished' event handler:
331 r1_bio
->bios
[mirror
] = NULL
;
334 md_error(r1_bio
->mddev
, conf
->mirrors
[mirror
].rdev
);
335 /* an I/O failed, we can't clear the bitmap */
336 set_bit(R1BIO_Degraded
, &r1_bio
->state
);
339 * Set R1BIO_Uptodate in our master bio, so that
340 * we will return a good error code for to the higher
341 * levels even if IO on some other mirrored buffer fails.
343 * The 'master' represents the composite IO operation to
344 * user-side. So if something waits for IO, then it will
345 * wait for the 'master' bio.
347 set_bit(R1BIO_Uptodate
, &r1_bio
->state
);
349 update_head_pos(mirror
, r1_bio
);
352 if (test_bit(WriteMostly
, &conf
->mirrors
[mirror
].rdev
->flags
))
353 atomic_dec(&r1_bio
->behind_remaining
);
355 /* In behind mode, we ACK the master bio once the I/O has safely
356 * reached all non-writemostly disks. Setting the Returned bit
357 * ensures that this gets done only once -- we don't ever want to
358 * return -EIO here, instead we'll wait */
360 if (atomic_read(&r1_bio
->behind_remaining
) >= (atomic_read(&r1_bio
->remaining
)-1) &&
361 test_bit(R1BIO_Uptodate
, &r1_bio
->state
)) {
362 /* Maybe we can return now */
363 if (!test_and_set_bit(R1BIO_Returned
, &r1_bio
->state
)) {
364 struct bio
*mbio
= r1_bio
->master_bio
;
365 PRINTK(KERN_DEBUG
"raid1: behind end write sectors %llu-%llu\n",
366 (unsigned long long) mbio
->bi_sector
,
367 (unsigned long long) mbio
->bi_sector
+
368 (mbio
->bi_size
>> 9) - 1);
373 rdev_dec_pending(conf
->mirrors
[mirror
].rdev
, conf
->mddev
);
377 * Let's see if all mirrored write operations have finished
380 if (atomic_dec_and_test(&r1_bio
->remaining
)) {
381 if (test_bit(R1BIO_BarrierRetry
, &r1_bio
->state
))
382 reschedule_retry(r1_bio
);
384 /* it really is the end of this request */
385 if (test_bit(R1BIO_BehindIO
, &r1_bio
->state
)) {
386 /* free extra copy of the data pages */
387 int i
= bio
->bi_vcnt
;
389 safe_put_page(bio
->bi_io_vec
[i
].bv_page
);
391 /* clear the bitmap if all writes complete successfully */
392 bitmap_endwrite(r1_bio
->mddev
->bitmap
, r1_bio
->sector
,
394 !test_bit(R1BIO_Degraded
, &r1_bio
->state
),
396 md_write_end(r1_bio
->mddev
);
397 raid_end_bio_io(r1_bio
);
407 * This routine returns the disk from which the requested read should
408 * be done. There is a per-array 'next expected sequential IO' sector
409 * number - if this matches on the next IO then we use the last disk.
410 * There is also a per-disk 'last know head position' sector that is
411 * maintained from IRQ contexts, both the normal and the resync IO
412 * completion handlers update this position correctly. If there is no
413 * perfect sequential match then we pick the disk whose head is closest.
415 * If there are 2 mirrors in the same 2 devices, performance degrades
416 * because position is mirror, not device based.
418 * The rdev for the device selected will have nr_pending incremented.
420 static int read_balance(conf_t
*conf
, r1bio_t
*r1_bio
)
422 const sector_t this_sector
= r1_bio
->sector
;
423 int new_disk
= conf
->last_used
, disk
= new_disk
;
425 const int sectors
= r1_bio
->sectors
;
426 sector_t new_distance
, current_distance
;
431 * Check if we can balance. We can balance on the whole
432 * device if no resync is going on, or below the resync window.
433 * We take the first readable disk when above the resync window.
436 if (conf
->mddev
->recovery_cp
< MaxSector
&&
437 (this_sector
+ sectors
>= conf
->next_resync
)) {
438 /* Choose the first operational device, for consistancy */
441 for (rdev
= rcu_dereference(conf
->mirrors
[new_disk
].rdev
);
442 r1_bio
->bios
[new_disk
] == IO_BLOCKED
||
443 !rdev
|| !test_bit(In_sync
, &rdev
->flags
)
444 || test_bit(WriteMostly
, &rdev
->flags
);
445 rdev
= rcu_dereference(conf
->mirrors
[++new_disk
].rdev
)) {
447 if (rdev
&& test_bit(In_sync
, &rdev
->flags
) &&
448 r1_bio
->bios
[new_disk
] != IO_BLOCKED
)
449 wonly_disk
= new_disk
;
451 if (new_disk
== conf
->raid_disks
- 1) {
452 new_disk
= wonly_disk
;
460 /* make sure the disk is operational */
461 for (rdev
= rcu_dereference(conf
->mirrors
[new_disk
].rdev
);
462 r1_bio
->bios
[new_disk
] == IO_BLOCKED
||
463 !rdev
|| !test_bit(In_sync
, &rdev
->flags
) ||
464 test_bit(WriteMostly
, &rdev
->flags
);
465 rdev
= rcu_dereference(conf
->mirrors
[new_disk
].rdev
)) {
467 if (rdev
&& test_bit(In_sync
, &rdev
->flags
) &&
468 r1_bio
->bios
[new_disk
] != IO_BLOCKED
)
469 wonly_disk
= new_disk
;
472 new_disk
= conf
->raid_disks
;
474 if (new_disk
== disk
) {
475 new_disk
= wonly_disk
;
484 /* now disk == new_disk == starting point for search */
487 * Don't change to another disk for sequential reads:
489 if (conf
->next_seq_sect
== this_sector
)
491 if (this_sector
== conf
->mirrors
[new_disk
].head_position
)
494 current_distance
= abs(this_sector
- conf
->mirrors
[disk
].head_position
);
496 /* Find the disk whose head is closest */
500 disk
= conf
->raid_disks
;
503 rdev
= rcu_dereference(conf
->mirrors
[disk
].rdev
);
505 if (!rdev
|| r1_bio
->bios
[disk
] == IO_BLOCKED
||
506 !test_bit(In_sync
, &rdev
->flags
) ||
507 test_bit(WriteMostly
, &rdev
->flags
))
510 if (!atomic_read(&rdev
->nr_pending
)) {
514 new_distance
= abs(this_sector
- conf
->mirrors
[disk
].head_position
);
515 if (new_distance
< current_distance
) {
516 current_distance
= new_distance
;
519 } while (disk
!= conf
->last_used
);
525 rdev
= rcu_dereference(conf
->mirrors
[new_disk
].rdev
);
528 atomic_inc(&rdev
->nr_pending
);
529 if (!test_bit(In_sync
, &rdev
->flags
)) {
530 /* cannot risk returning a device that failed
531 * before we inc'ed nr_pending
533 rdev_dec_pending(rdev
, conf
->mddev
);
536 conf
->next_seq_sect
= this_sector
+ sectors
;
537 conf
->last_used
= new_disk
;
544 static void unplug_slaves(mddev_t
*mddev
)
546 conf_t
*conf
= mddev
->private;
550 for (i
=0; i
<mddev
->raid_disks
; i
++) {
551 mdk_rdev_t
*rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
552 if (rdev
&& !test_bit(Faulty
, &rdev
->flags
) && atomic_read(&rdev
->nr_pending
)) {
553 struct request_queue
*r_queue
= bdev_get_queue(rdev
->bdev
);
555 atomic_inc(&rdev
->nr_pending
);
560 rdev_dec_pending(rdev
, mddev
);
567 static void raid1_unplug(struct request_queue
*q
)
569 mddev_t
*mddev
= q
->queuedata
;
571 unplug_slaves(mddev
);
572 md_wakeup_thread(mddev
->thread
);
575 static int raid1_congested(void *data
, int bits
)
577 mddev_t
*mddev
= data
;
578 conf_t
*conf
= mddev
->private;
581 if (mddev_congested(mddev
, bits
))
585 for (i
= 0; i
< mddev
->raid_disks
; i
++) {
586 mdk_rdev_t
*rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
587 if (rdev
&& !test_bit(Faulty
, &rdev
->flags
)) {
588 struct request_queue
*q
= bdev_get_queue(rdev
->bdev
);
590 /* Note the '|| 1' - when read_balance prefers
591 * non-congested targets, it can be removed
593 if ((bits
& (1<<BDI_async_congested
)) || 1)
594 ret
|= bdi_congested(&q
->backing_dev_info
, bits
);
596 ret
&= bdi_congested(&q
->backing_dev_info
, bits
);
604 static int flush_pending_writes(conf_t
*conf
)
606 /* Any writes that have been queued but are awaiting
607 * bitmap updates get flushed here.
608 * We return 1 if any requests were actually submitted.
612 spin_lock_irq(&conf
->device_lock
);
614 if (conf
->pending_bio_list
.head
) {
616 bio
= bio_list_get(&conf
->pending_bio_list
);
617 blk_remove_plug(conf
->mddev
->queue
);
618 spin_unlock_irq(&conf
->device_lock
);
619 /* flush any pending bitmap writes to
620 * disk before proceeding w/ I/O */
621 bitmap_unplug(conf
->mddev
->bitmap
);
623 while (bio
) { /* submit pending writes */
624 struct bio
*next
= bio
->bi_next
;
626 generic_make_request(bio
);
631 spin_unlock_irq(&conf
->device_lock
);
636 * Sometimes we need to suspend IO while we do something else,
637 * either some resync/recovery, or reconfigure the array.
638 * To do this we raise a 'barrier'.
639 * The 'barrier' is a counter that can be raised multiple times
640 * to count how many activities are happening which preclude
642 * We can only raise the barrier if there is no pending IO.
643 * i.e. if nr_pending == 0.
644 * We choose only to raise the barrier if no-one is waiting for the
645 * barrier to go down. This means that as soon as an IO request
646 * is ready, no other operations which require a barrier will start
647 * until the IO request has had a chance.
649 * So: regular IO calls 'wait_barrier'. When that returns there
650 * is no backgroup IO happening, It must arrange to call
651 * allow_barrier when it has finished its IO.
652 * backgroup IO calls must call raise_barrier. Once that returns
653 * there is no normal IO happeing. It must arrange to call
654 * lower_barrier when the particular background IO completes.
656 #define RESYNC_DEPTH 32
658 static void raise_barrier(conf_t
*conf
)
660 spin_lock_irq(&conf
->resync_lock
);
662 /* Wait until no block IO is waiting */
663 wait_event_lock_irq(conf
->wait_barrier
, !conf
->nr_waiting
,
665 raid1_unplug(conf
->mddev
->queue
));
667 /* block any new IO from starting */
670 /* No wait for all pending IO to complete */
671 wait_event_lock_irq(conf
->wait_barrier
,
672 !conf
->nr_pending
&& conf
->barrier
< RESYNC_DEPTH
,
674 raid1_unplug(conf
->mddev
->queue
));
676 spin_unlock_irq(&conf
->resync_lock
);
679 static void lower_barrier(conf_t
*conf
)
682 BUG_ON(conf
->barrier
<= 0);
683 spin_lock_irqsave(&conf
->resync_lock
, flags
);
685 spin_unlock_irqrestore(&conf
->resync_lock
, flags
);
686 wake_up(&conf
->wait_barrier
);
689 static void wait_barrier(conf_t
*conf
)
691 spin_lock_irq(&conf
->resync_lock
);
694 wait_event_lock_irq(conf
->wait_barrier
, !conf
->barrier
,
696 raid1_unplug(conf
->mddev
->queue
));
700 spin_unlock_irq(&conf
->resync_lock
);
703 static void allow_barrier(conf_t
*conf
)
706 spin_lock_irqsave(&conf
->resync_lock
, flags
);
708 spin_unlock_irqrestore(&conf
->resync_lock
, flags
);
709 wake_up(&conf
->wait_barrier
);
712 static void freeze_array(conf_t
*conf
)
714 /* stop syncio and normal IO and wait for everything to
716 * We increment barrier and nr_waiting, and then
717 * wait until nr_pending match nr_queued+1
718 * This is called in the context of one normal IO request
719 * that has failed. Thus any sync request that might be pending
720 * will be blocked by nr_pending, and we need to wait for
721 * pending IO requests to complete or be queued for re-try.
722 * Thus the number queued (nr_queued) plus this request (1)
723 * must match the number of pending IOs (nr_pending) before
726 spin_lock_irq(&conf
->resync_lock
);
729 wait_event_lock_irq(conf
->wait_barrier
,
730 conf
->nr_pending
== conf
->nr_queued
+1,
732 ({ flush_pending_writes(conf
);
733 raid1_unplug(conf
->mddev
->queue
); }));
734 spin_unlock_irq(&conf
->resync_lock
);
736 static void unfreeze_array(conf_t
*conf
)
738 /* reverse the effect of the freeze */
739 spin_lock_irq(&conf
->resync_lock
);
742 wake_up(&conf
->wait_barrier
);
743 spin_unlock_irq(&conf
->resync_lock
);
747 /* duplicate the data pages for behind I/O */
748 static struct page
**alloc_behind_pages(struct bio
*bio
)
751 struct bio_vec
*bvec
;
752 struct page
**pages
= kzalloc(bio
->bi_vcnt
* sizeof(struct page
*),
754 if (unlikely(!pages
))
757 bio_for_each_segment(bvec
, bio
, i
) {
758 pages
[i
] = alloc_page(GFP_NOIO
);
759 if (unlikely(!pages
[i
]))
761 memcpy(kmap(pages
[i
]) + bvec
->bv_offset
,
762 kmap(bvec
->bv_page
) + bvec
->bv_offset
, bvec
->bv_len
);
764 kunmap(bvec
->bv_page
);
771 for (i
= 0; i
< bio
->bi_vcnt
&& pages
[i
]; i
++)
774 PRINTK("%dB behind alloc failed, doing sync I/O\n", bio
->bi_size
);
778 static int make_request(mddev_t
*mddev
, struct bio
* bio
)
780 conf_t
*conf
= mddev
->private;
781 mirror_info_t
*mirror
;
783 struct bio
*read_bio
;
784 int i
, targets
= 0, disks
;
785 struct bitmap
*bitmap
;
788 struct page
**behind_pages
= NULL
;
789 const int rw
= bio_data_dir(bio
);
790 const unsigned long do_sync
= (bio
->bi_rw
& REQ_SYNC
);
791 unsigned long do_barriers
;
792 mdk_rdev_t
*blocked_rdev
;
795 * Register the new request and wait if the reconstruction
796 * thread has put up a bar for new requests.
797 * Continue immediately if no resync is active currently.
798 * We test barriers_work *after* md_write_start as md_write_start
799 * may cause the first superblock write, and that will check out
803 md_write_start(mddev
, bio
); /* wait on superblock update early */
805 if (bio_data_dir(bio
) == WRITE
&&
806 bio
->bi_sector
+ bio
->bi_size
/512 > mddev
->suspend_lo
&&
807 bio
->bi_sector
< mddev
->suspend_hi
) {
808 /* As the suspend_* range is controlled by
809 * userspace, we want an interruptible
814 flush_signals(current
);
815 prepare_to_wait(&conf
->wait_barrier
,
816 &w
, TASK_INTERRUPTIBLE
);
817 if (bio
->bi_sector
+ bio
->bi_size
/512 <= mddev
->suspend_lo
||
818 bio
->bi_sector
>= mddev
->suspend_hi
)
822 finish_wait(&conf
->wait_barrier
, &w
);
824 if (unlikely(!mddev
->barriers_work
&&
825 (bio
->bi_rw
& REQ_HARDBARRIER
))) {
828 bio_endio(bio
, -EOPNOTSUPP
);
834 bitmap
= mddev
->bitmap
;
837 * make_request() can abort the operation when READA is being
838 * used and no empty request is available.
841 r1_bio
= mempool_alloc(conf
->r1bio_pool
, GFP_NOIO
);
843 r1_bio
->master_bio
= bio
;
844 r1_bio
->sectors
= bio
->bi_size
>> 9;
846 r1_bio
->mddev
= mddev
;
847 r1_bio
->sector
= bio
->bi_sector
;
851 * read balancing logic:
853 int rdisk
= read_balance(conf
, r1_bio
);
856 /* couldn't find anywhere to read from */
857 raid_end_bio_io(r1_bio
);
860 mirror
= conf
->mirrors
+ rdisk
;
862 if (test_bit(WriteMostly
, &mirror
->rdev
->flags
) &&
864 /* Reading from a write-mostly device must
865 * take care not to over-take any writes
868 wait_event(bitmap
->behind_wait
,
869 atomic_read(&bitmap
->behind_writes
) == 0);
871 r1_bio
->read_disk
= rdisk
;
873 read_bio
= bio_clone(bio
, GFP_NOIO
);
875 r1_bio
->bios
[rdisk
] = read_bio
;
877 read_bio
->bi_sector
= r1_bio
->sector
+ mirror
->rdev
->data_offset
;
878 read_bio
->bi_bdev
= mirror
->rdev
->bdev
;
879 read_bio
->bi_end_io
= raid1_end_read_request
;
880 read_bio
->bi_rw
= READ
| do_sync
;
881 read_bio
->bi_private
= r1_bio
;
883 generic_make_request(read_bio
);
890 /* first select target devices under spinlock and
891 * inc refcount on their rdev. Record them by setting
894 disks
= conf
->raid_disks
;
898 for (i
= 0; i
< disks
; i
++) {
899 mdk_rdev_t
*rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
900 if (rdev
&& unlikely(test_bit(Blocked
, &rdev
->flags
))) {
901 atomic_inc(&rdev
->nr_pending
);
905 if (rdev
&& !test_bit(Faulty
, &rdev
->flags
)) {
906 atomic_inc(&rdev
->nr_pending
);
907 if (test_bit(Faulty
, &rdev
->flags
)) {
908 rdev_dec_pending(rdev
, mddev
);
909 r1_bio
->bios
[i
] = NULL
;
911 r1_bio
->bios
[i
] = bio
;
915 r1_bio
->bios
[i
] = NULL
;
919 if (unlikely(blocked_rdev
)) {
920 /* Wait for this device to become unblocked */
923 for (j
= 0; j
< i
; j
++)
925 rdev_dec_pending(conf
->mirrors
[j
].rdev
, mddev
);
928 md_wait_for_blocked_rdev(blocked_rdev
, mddev
);
933 BUG_ON(targets
== 0); /* we never fail the last device */
935 if (targets
< conf
->raid_disks
) {
936 /* array is degraded, we will not clear the bitmap
937 * on I/O completion (see raid1_end_write_request) */
938 set_bit(R1BIO_Degraded
, &r1_bio
->state
);
942 * Not if there are too many, or cannot allocate memory,
943 * or a reader on WriteMostly is waiting for behind writes
946 (atomic_read(&bitmap
->behind_writes
)
947 < mddev
->bitmap_info
.max_write_behind
) &&
948 !waitqueue_active(&bitmap
->behind_wait
) &&
949 (behind_pages
= alloc_behind_pages(bio
)) != NULL
)
950 set_bit(R1BIO_BehindIO
, &r1_bio
->state
);
952 atomic_set(&r1_bio
->remaining
, 0);
953 atomic_set(&r1_bio
->behind_remaining
, 0);
955 do_barriers
= bio
->bi_rw
& REQ_HARDBARRIER
;
957 set_bit(R1BIO_Barrier
, &r1_bio
->state
);
960 for (i
= 0; i
< disks
; i
++) {
962 if (!r1_bio
->bios
[i
])
965 mbio
= bio_clone(bio
, GFP_NOIO
);
966 r1_bio
->bios
[i
] = mbio
;
968 mbio
->bi_sector
= r1_bio
->sector
+ conf
->mirrors
[i
].rdev
->data_offset
;
969 mbio
->bi_bdev
= conf
->mirrors
[i
].rdev
->bdev
;
970 mbio
->bi_end_io
= raid1_end_write_request
;
971 mbio
->bi_rw
= WRITE
| do_barriers
| do_sync
;
972 mbio
->bi_private
= r1_bio
;
975 struct bio_vec
*bvec
;
978 /* Yes, I really want the '__' version so that
979 * we clear any unused pointer in the io_vec, rather
980 * than leave them unchanged. This is important
981 * because when we come to free the pages, we won't
982 * know the originial bi_idx, so we just free
985 __bio_for_each_segment(bvec
, mbio
, j
, 0)
986 bvec
->bv_page
= behind_pages
[j
];
987 if (test_bit(WriteMostly
, &conf
->mirrors
[i
].rdev
->flags
))
988 atomic_inc(&r1_bio
->behind_remaining
);
991 atomic_inc(&r1_bio
->remaining
);
993 bio_list_add(&bl
, mbio
);
995 kfree(behind_pages
); /* the behind pages are attached to the bios now */
997 bitmap_startwrite(bitmap
, bio
->bi_sector
, r1_bio
->sectors
,
998 test_bit(R1BIO_BehindIO
, &r1_bio
->state
));
999 spin_lock_irqsave(&conf
->device_lock
, flags
);
1000 bio_list_merge(&conf
->pending_bio_list
, &bl
);
1003 blk_plug_device(mddev
->queue
);
1004 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
1006 /* In case raid1d snuck into freeze_array */
1007 wake_up(&conf
->wait_barrier
);
1010 md_wakeup_thread(mddev
->thread
);
1015 static void status(struct seq_file
*seq
, mddev_t
*mddev
)
1017 conf_t
*conf
= mddev
->private;
1020 seq_printf(seq
, " [%d/%d] [", conf
->raid_disks
,
1021 conf
->raid_disks
- mddev
->degraded
);
1023 for (i
= 0; i
< conf
->raid_disks
; i
++) {
1024 mdk_rdev_t
*rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
1025 seq_printf(seq
, "%s",
1026 rdev
&& test_bit(In_sync
, &rdev
->flags
) ? "U" : "_");
1029 seq_printf(seq
, "]");
1033 static void error(mddev_t
*mddev
, mdk_rdev_t
*rdev
)
1035 char b
[BDEVNAME_SIZE
];
1036 conf_t
*conf
= mddev
->private;
1039 * If it is not operational, then we have already marked it as dead
1040 * else if it is the last working disks, ignore the error, let the
1041 * next level up know.
1042 * else mark the drive as failed
1044 if (test_bit(In_sync
, &rdev
->flags
)
1045 && (conf
->raid_disks
- mddev
->degraded
) == 1) {
1047 * Don't fail the drive, act as though we were just a
1048 * normal single drive.
1049 * However don't try a recovery from this drive as
1050 * it is very likely to fail.
1052 mddev
->recovery_disabled
= 1;
1055 if (test_and_clear_bit(In_sync
, &rdev
->flags
)) {
1056 unsigned long flags
;
1057 spin_lock_irqsave(&conf
->device_lock
, flags
);
1059 set_bit(Faulty
, &rdev
->flags
);
1060 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
1062 * if recovery is running, make sure it aborts.
1064 set_bit(MD_RECOVERY_INTR
, &mddev
->recovery
);
1066 set_bit(Faulty
, &rdev
->flags
);
1067 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
1068 printk(KERN_ALERT
"md/raid1:%s: Disk failure on %s, disabling device.\n"
1069 KERN_ALERT
"md/raid1:%s: Operation continuing on %d devices.\n",
1070 mdname(mddev
), bdevname(rdev
->bdev
, b
),
1071 mdname(mddev
), conf
->raid_disks
- mddev
->degraded
);
1074 static void print_conf(conf_t
*conf
)
1078 printk(KERN_DEBUG
"RAID1 conf printout:\n");
1080 printk(KERN_DEBUG
"(!conf)\n");
1083 printk(KERN_DEBUG
" --- wd:%d rd:%d\n", conf
->raid_disks
- conf
->mddev
->degraded
,
1087 for (i
= 0; i
< conf
->raid_disks
; i
++) {
1088 char b
[BDEVNAME_SIZE
];
1089 mdk_rdev_t
*rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
1091 printk(KERN_DEBUG
" disk %d, wo:%d, o:%d, dev:%s\n",
1092 i
, !test_bit(In_sync
, &rdev
->flags
),
1093 !test_bit(Faulty
, &rdev
->flags
),
1094 bdevname(rdev
->bdev
,b
));
1099 static void close_sync(conf_t
*conf
)
1102 allow_barrier(conf
);
1104 mempool_destroy(conf
->r1buf_pool
);
1105 conf
->r1buf_pool
= NULL
;
1108 static int raid1_spare_active(mddev_t
*mddev
)
1111 conf_t
*conf
= mddev
->private;
1113 unsigned long flags
;
1116 * Find all failed disks within the RAID1 configuration
1117 * and mark them readable.
1118 * Called under mddev lock, so rcu protection not needed.
1120 for (i
= 0; i
< conf
->raid_disks
; i
++) {
1121 mdk_rdev_t
*rdev
= conf
->mirrors
[i
].rdev
;
1123 && !test_bit(Faulty
, &rdev
->flags
)
1124 && !test_and_set_bit(In_sync
, &rdev
->flags
)) {
1126 sysfs_notify_dirent(rdev
->sysfs_state
);
1129 spin_lock_irqsave(&conf
->device_lock
, flags
);
1130 mddev
->degraded
-= count
;
1131 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
1138 static int raid1_add_disk(mddev_t
*mddev
, mdk_rdev_t
*rdev
)
1140 conf_t
*conf
= mddev
->private;
1145 int last
= mddev
->raid_disks
- 1;
1147 if (rdev
->raid_disk
>= 0)
1148 first
= last
= rdev
->raid_disk
;
1150 for (mirror
= first
; mirror
<= last
; mirror
++)
1151 if ( !(p
=conf
->mirrors
+mirror
)->rdev
) {
1153 disk_stack_limits(mddev
->gendisk
, rdev
->bdev
,
1154 rdev
->data_offset
<< 9);
1155 /* as we don't honour merge_bvec_fn, we must
1156 * never risk violating it, so limit
1157 * ->max_segments to one lying with a single
1158 * page, as a one page request is never in
1161 if (rdev
->bdev
->bd_disk
->queue
->merge_bvec_fn
) {
1162 blk_queue_max_segments(mddev
->queue
, 1);
1163 blk_queue_segment_boundary(mddev
->queue
,
1164 PAGE_CACHE_SIZE
- 1);
1167 p
->head_position
= 0;
1168 rdev
->raid_disk
= mirror
;
1170 /* As all devices are equivalent, we don't need a full recovery
1171 * if this was recently any drive of the array
1173 if (rdev
->saved_raid_disk
< 0)
1175 rcu_assign_pointer(p
->rdev
, rdev
);
1178 md_integrity_add_rdev(rdev
, mddev
);
1183 static int raid1_remove_disk(mddev_t
*mddev
, int number
)
1185 conf_t
*conf
= mddev
->private;
1188 mirror_info_t
*p
= conf
->mirrors
+ number
;
1193 if (test_bit(In_sync
, &rdev
->flags
) ||
1194 atomic_read(&rdev
->nr_pending
)) {
1198 /* Only remove non-faulty devices is recovery
1201 if (!test_bit(Faulty
, &rdev
->flags
) &&
1202 !mddev
->recovery_disabled
&&
1203 mddev
->degraded
< conf
->raid_disks
) {
1209 if (atomic_read(&rdev
->nr_pending
)) {
1210 /* lost the race, try later */
1215 md_integrity_register(mddev
);
1224 static void end_sync_read(struct bio
*bio
, int error
)
1226 r1bio_t
*r1_bio
= bio
->bi_private
;
1229 for (i
=r1_bio
->mddev
->raid_disks
; i
--; )
1230 if (r1_bio
->bios
[i
] == bio
)
1233 update_head_pos(i
, r1_bio
);
1235 * we have read a block, now it needs to be re-written,
1236 * or re-read if the read failed.
1237 * We don't do much here, just schedule handling by raid1d
1239 if (test_bit(BIO_UPTODATE
, &bio
->bi_flags
))
1240 set_bit(R1BIO_Uptodate
, &r1_bio
->state
);
1242 if (atomic_dec_and_test(&r1_bio
->remaining
))
1243 reschedule_retry(r1_bio
);
1246 static void end_sync_write(struct bio
*bio
, int error
)
1248 int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
1249 r1bio_t
*r1_bio
= bio
->bi_private
;
1250 mddev_t
*mddev
= r1_bio
->mddev
;
1251 conf_t
*conf
= mddev
->private;
1255 for (i
= 0; i
< conf
->raid_disks
; i
++)
1256 if (r1_bio
->bios
[i
] == bio
) {
1261 int sync_blocks
= 0;
1262 sector_t s
= r1_bio
->sector
;
1263 long sectors_to_go
= r1_bio
->sectors
;
1264 /* make sure these bits doesn't get cleared. */
1266 bitmap_end_sync(mddev
->bitmap
, s
,
1269 sectors_to_go
-= sync_blocks
;
1270 } while (sectors_to_go
> 0);
1271 md_error(mddev
, conf
->mirrors
[mirror
].rdev
);
1274 update_head_pos(mirror
, r1_bio
);
1276 if (atomic_dec_and_test(&r1_bio
->remaining
)) {
1277 sector_t s
= r1_bio
->sectors
;
1279 md_done_sync(mddev
, s
, uptodate
);
1283 static void sync_request_write(mddev_t
*mddev
, r1bio_t
*r1_bio
)
1285 conf_t
*conf
= mddev
->private;
1287 int disks
= conf
->raid_disks
;
1288 struct bio
*bio
, *wbio
;
1290 bio
= r1_bio
->bios
[r1_bio
->read_disk
];
1293 if (test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
)) {
1294 /* We have read all readable devices. If we haven't
1295 * got the block, then there is no hope left.
1296 * If we have, then we want to do a comparison
1297 * and skip the write if everything is the same.
1298 * If any blocks failed to read, then we need to
1299 * attempt an over-write
1302 if (!test_bit(R1BIO_Uptodate
, &r1_bio
->state
)) {
1303 for (i
=0; i
<mddev
->raid_disks
; i
++)
1304 if (r1_bio
->bios
[i
]->bi_end_io
== end_sync_read
)
1305 md_error(mddev
, conf
->mirrors
[i
].rdev
);
1307 md_done_sync(mddev
, r1_bio
->sectors
, 1);
1311 for (primary
=0; primary
<mddev
->raid_disks
; primary
++)
1312 if (r1_bio
->bios
[primary
]->bi_end_io
== end_sync_read
&&
1313 test_bit(BIO_UPTODATE
, &r1_bio
->bios
[primary
]->bi_flags
)) {
1314 r1_bio
->bios
[primary
]->bi_end_io
= NULL
;
1315 rdev_dec_pending(conf
->mirrors
[primary
].rdev
, mddev
);
1318 r1_bio
->read_disk
= primary
;
1319 for (i
=0; i
<mddev
->raid_disks
; i
++)
1320 if (r1_bio
->bios
[i
]->bi_end_io
== end_sync_read
) {
1322 int vcnt
= r1_bio
->sectors
>> (PAGE_SHIFT
- 9);
1323 struct bio
*pbio
= r1_bio
->bios
[primary
];
1324 struct bio
*sbio
= r1_bio
->bios
[i
];
1326 if (test_bit(BIO_UPTODATE
, &sbio
->bi_flags
)) {
1327 for (j
= vcnt
; j
-- ; ) {
1329 p
= pbio
->bi_io_vec
[j
].bv_page
;
1330 s
= sbio
->bi_io_vec
[j
].bv_page
;
1331 if (memcmp(page_address(p
),
1339 mddev
->resync_mismatches
+= r1_bio
->sectors
;
1340 if (j
< 0 || (test_bit(MD_RECOVERY_CHECK
, &mddev
->recovery
)
1341 && test_bit(BIO_UPTODATE
, &sbio
->bi_flags
))) {
1342 sbio
->bi_end_io
= NULL
;
1343 rdev_dec_pending(conf
->mirrors
[i
].rdev
, mddev
);
1345 /* fixup the bio for reuse */
1347 sbio
->bi_vcnt
= vcnt
;
1348 sbio
->bi_size
= r1_bio
->sectors
<< 9;
1350 sbio
->bi_phys_segments
= 0;
1351 sbio
->bi_flags
&= ~(BIO_POOL_MASK
- 1);
1352 sbio
->bi_flags
|= 1 << BIO_UPTODATE
;
1353 sbio
->bi_next
= NULL
;
1354 sbio
->bi_sector
= r1_bio
->sector
+
1355 conf
->mirrors
[i
].rdev
->data_offset
;
1356 sbio
->bi_bdev
= conf
->mirrors
[i
].rdev
->bdev
;
1357 size
= sbio
->bi_size
;
1358 for (j
= 0; j
< vcnt
; j
++) {
1360 bi
= &sbio
->bi_io_vec
[j
];
1362 if (size
> PAGE_SIZE
)
1363 bi
->bv_len
= PAGE_SIZE
;
1367 memcpy(page_address(bi
->bv_page
),
1368 page_address(pbio
->bi_io_vec
[j
].bv_page
),
1375 if (!test_bit(R1BIO_Uptodate
, &r1_bio
->state
)) {
1376 /* ouch - failed to read all of that.
1377 * Try some synchronous reads of other devices to get
1378 * good data, much like with normal read errors. Only
1379 * read into the pages we already have so we don't
1380 * need to re-issue the read request.
1381 * We don't need to freeze the array, because being in an
1382 * active sync request, there is no normal IO, and
1383 * no overlapping syncs.
1385 sector_t sect
= r1_bio
->sector
;
1386 int sectors
= r1_bio
->sectors
;
1391 int d
= r1_bio
->read_disk
;
1395 if (s
> (PAGE_SIZE
>>9))
1398 if (r1_bio
->bios
[d
]->bi_end_io
== end_sync_read
) {
1399 /* No rcu protection needed here devices
1400 * can only be removed when no resync is
1401 * active, and resync is currently active
1403 rdev
= conf
->mirrors
[d
].rdev
;
1404 if (sync_page_io(rdev
->bdev
,
1405 sect
+ rdev
->data_offset
,
1407 bio
->bi_io_vec
[idx
].bv_page
,
1414 if (d
== conf
->raid_disks
)
1416 } while (!success
&& d
!= r1_bio
->read_disk
);
1420 /* write it back and re-read */
1421 set_bit(R1BIO_Uptodate
, &r1_bio
->state
);
1422 while (d
!= r1_bio
->read_disk
) {
1424 d
= conf
->raid_disks
;
1426 if (r1_bio
->bios
[d
]->bi_end_io
!= end_sync_read
)
1428 rdev
= conf
->mirrors
[d
].rdev
;
1429 atomic_add(s
, &rdev
->corrected_errors
);
1430 if (sync_page_io(rdev
->bdev
,
1431 sect
+ rdev
->data_offset
,
1433 bio
->bi_io_vec
[idx
].bv_page
,
1435 md_error(mddev
, rdev
);
1438 while (d
!= r1_bio
->read_disk
) {
1440 d
= conf
->raid_disks
;
1442 if (r1_bio
->bios
[d
]->bi_end_io
!= end_sync_read
)
1444 rdev
= conf
->mirrors
[d
].rdev
;
1445 if (sync_page_io(rdev
->bdev
,
1446 sect
+ rdev
->data_offset
,
1448 bio
->bi_io_vec
[idx
].bv_page
,
1450 md_error(mddev
, rdev
);
1453 char b
[BDEVNAME_SIZE
];
1454 /* Cannot read from anywhere, array is toast */
1455 md_error(mddev
, conf
->mirrors
[r1_bio
->read_disk
].rdev
);
1456 printk(KERN_ALERT
"md/raid1:%s: %s: unrecoverable I/O read error"
1457 " for block %llu\n",
1459 bdevname(bio
->bi_bdev
, b
),
1460 (unsigned long long)r1_bio
->sector
);
1461 md_done_sync(mddev
, r1_bio
->sectors
, 0);
1474 atomic_set(&r1_bio
->remaining
, 1);
1475 for (i
= 0; i
< disks
; i
++) {
1476 wbio
= r1_bio
->bios
[i
];
1477 if (wbio
->bi_end_io
== NULL
||
1478 (wbio
->bi_end_io
== end_sync_read
&&
1479 (i
== r1_bio
->read_disk
||
1480 !test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
))))
1483 wbio
->bi_rw
= WRITE
;
1484 wbio
->bi_end_io
= end_sync_write
;
1485 atomic_inc(&r1_bio
->remaining
);
1486 md_sync_acct(conf
->mirrors
[i
].rdev
->bdev
, wbio
->bi_size
>> 9);
1488 generic_make_request(wbio
);
1491 if (atomic_dec_and_test(&r1_bio
->remaining
)) {
1492 /* if we're here, all write(s) have completed, so clean up */
1493 md_done_sync(mddev
, r1_bio
->sectors
, 1);
1499 * This is a kernel thread which:
1501 * 1. Retries failed read operations on working mirrors.
1502 * 2. Updates the raid superblock when problems encounter.
1503 * 3. Performs writes following reads for array syncronising.
1506 static void fix_read_error(conf_t
*conf
, int read_disk
,
1507 sector_t sect
, int sectors
)
1509 mddev_t
*mddev
= conf
->mddev
;
1517 if (s
> (PAGE_SIZE
>>9))
1521 /* Note: no rcu protection needed here
1522 * as this is synchronous in the raid1d thread
1523 * which is the thread that might remove
1524 * a device. If raid1d ever becomes multi-threaded....
1526 rdev
= conf
->mirrors
[d
].rdev
;
1528 test_bit(In_sync
, &rdev
->flags
) &&
1529 sync_page_io(rdev
->bdev
,
1530 sect
+ rdev
->data_offset
,
1532 conf
->tmppage
, READ
))
1536 if (d
== conf
->raid_disks
)
1539 } while (!success
&& d
!= read_disk
);
1542 /* Cannot read from anywhere -- bye bye array */
1543 md_error(mddev
, conf
->mirrors
[read_disk
].rdev
);
1546 /* write it back and re-read */
1548 while (d
!= read_disk
) {
1550 d
= conf
->raid_disks
;
1552 rdev
= conf
->mirrors
[d
].rdev
;
1554 test_bit(In_sync
, &rdev
->flags
)) {
1555 if (sync_page_io(rdev
->bdev
,
1556 sect
+ rdev
->data_offset
,
1557 s
<<9, conf
->tmppage
, WRITE
)
1559 /* Well, this device is dead */
1560 md_error(mddev
, rdev
);
1564 while (d
!= read_disk
) {
1565 char b
[BDEVNAME_SIZE
];
1567 d
= conf
->raid_disks
;
1569 rdev
= conf
->mirrors
[d
].rdev
;
1571 test_bit(In_sync
, &rdev
->flags
)) {
1572 if (sync_page_io(rdev
->bdev
,
1573 sect
+ rdev
->data_offset
,
1574 s
<<9, conf
->tmppage
, READ
)
1576 /* Well, this device is dead */
1577 md_error(mddev
, rdev
);
1579 atomic_add(s
, &rdev
->corrected_errors
);
1581 "md/raid1:%s: read error corrected "
1582 "(%d sectors at %llu on %s)\n",
1584 (unsigned long long)(sect
+
1586 bdevname(rdev
->bdev
, b
));
1595 static void raid1d(mddev_t
*mddev
)
1599 unsigned long flags
;
1600 conf_t
*conf
= mddev
->private;
1601 struct list_head
*head
= &conf
->retry_list
;
1605 md_check_recovery(mddev
);
1608 char b
[BDEVNAME_SIZE
];
1610 unplug
+= flush_pending_writes(conf
);
1612 spin_lock_irqsave(&conf
->device_lock
, flags
);
1613 if (list_empty(head
)) {
1614 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
1617 r1_bio
= list_entry(head
->prev
, r1bio_t
, retry_list
);
1618 list_del(head
->prev
);
1620 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
1622 mddev
= r1_bio
->mddev
;
1623 conf
= mddev
->private;
1624 if (test_bit(R1BIO_IsSync
, &r1_bio
->state
)) {
1625 sync_request_write(mddev
, r1_bio
);
1627 } else if (test_bit(R1BIO_BarrierRetry
, &r1_bio
->state
)) {
1628 /* some requests in the r1bio were REQ_HARDBARRIER
1629 * requests which failed with -EOPNOTSUPP. Hohumm..
1630 * Better resubmit without the barrier.
1631 * We know which devices to resubmit for, because
1632 * all others have had their bios[] entry cleared.
1633 * We already have a nr_pending reference on these rdevs.
1636 const unsigned long do_sync
= (r1_bio
->master_bio
->bi_rw
& REQ_SYNC
);
1637 clear_bit(R1BIO_BarrierRetry
, &r1_bio
->state
);
1638 clear_bit(R1BIO_Barrier
, &r1_bio
->state
);
1639 for (i
=0; i
< conf
->raid_disks
; i
++)
1640 if (r1_bio
->bios
[i
])
1641 atomic_inc(&r1_bio
->remaining
);
1642 for (i
=0; i
< conf
->raid_disks
; i
++)
1643 if (r1_bio
->bios
[i
]) {
1644 struct bio_vec
*bvec
;
1647 bio
= bio_clone(r1_bio
->master_bio
, GFP_NOIO
);
1648 /* copy pages from the failed bio, as
1649 * this might be a write-behind device */
1650 __bio_for_each_segment(bvec
, bio
, j
, 0)
1651 bvec
->bv_page
= bio_iovec_idx(r1_bio
->bios
[i
], j
)->bv_page
;
1652 bio_put(r1_bio
->bios
[i
]);
1653 bio
->bi_sector
= r1_bio
->sector
+
1654 conf
->mirrors
[i
].rdev
->data_offset
;
1655 bio
->bi_bdev
= conf
->mirrors
[i
].rdev
->bdev
;
1656 bio
->bi_end_io
= raid1_end_write_request
;
1657 bio
->bi_rw
= WRITE
| do_sync
;
1658 bio
->bi_private
= r1_bio
;
1659 r1_bio
->bios
[i
] = bio
;
1660 generic_make_request(bio
);
1665 /* we got a read error. Maybe the drive is bad. Maybe just
1666 * the block and we can fix it.
1667 * We freeze all other IO, and try reading the block from
1668 * other devices. When we find one, we re-write
1669 * and check it that fixes the read error.
1670 * This is all done synchronously while the array is
1673 if (mddev
->ro
== 0) {
1675 fix_read_error(conf
, r1_bio
->read_disk
,
1678 unfreeze_array(conf
);
1681 conf
->mirrors
[r1_bio
->read_disk
].rdev
);
1683 bio
= r1_bio
->bios
[r1_bio
->read_disk
];
1684 if ((disk
=read_balance(conf
, r1_bio
)) == -1) {
1685 printk(KERN_ALERT
"md/raid1:%s: %s: unrecoverable I/O"
1686 " read error for block %llu\n",
1688 bdevname(bio
->bi_bdev
,b
),
1689 (unsigned long long)r1_bio
->sector
);
1690 raid_end_bio_io(r1_bio
);
1692 const unsigned long do_sync
= r1_bio
->master_bio
->bi_rw
& REQ_SYNC
;
1693 r1_bio
->bios
[r1_bio
->read_disk
] =
1694 mddev
->ro
? IO_BLOCKED
: NULL
;
1695 r1_bio
->read_disk
= disk
;
1697 bio
= bio_clone(r1_bio
->master_bio
, GFP_NOIO
);
1698 r1_bio
->bios
[r1_bio
->read_disk
] = bio
;
1699 rdev
= conf
->mirrors
[disk
].rdev
;
1700 if (printk_ratelimit())
1701 printk(KERN_ERR
"md/raid1:%s: redirecting sector %llu to"
1702 " other mirror: %s\n",
1704 (unsigned long long)r1_bio
->sector
,
1705 bdevname(rdev
->bdev
,b
));
1706 bio
->bi_sector
= r1_bio
->sector
+ rdev
->data_offset
;
1707 bio
->bi_bdev
= rdev
->bdev
;
1708 bio
->bi_end_io
= raid1_end_read_request
;
1709 bio
->bi_rw
= READ
| do_sync
;
1710 bio
->bi_private
= r1_bio
;
1712 generic_make_request(bio
);
1718 unplug_slaves(mddev
);
1722 static int init_resync(conf_t
*conf
)
1726 buffs
= RESYNC_WINDOW
/ RESYNC_BLOCK_SIZE
;
1727 BUG_ON(conf
->r1buf_pool
);
1728 conf
->r1buf_pool
= mempool_create(buffs
, r1buf_pool_alloc
, r1buf_pool_free
,
1730 if (!conf
->r1buf_pool
)
1732 conf
->next_resync
= 0;
1737 * perform a "sync" on one "block"
1739 * We need to make sure that no normal I/O request - particularly write
1740 * requests - conflict with active sync requests.
1742 * This is achieved by tracking pending requests and a 'barrier' concept
1743 * that can be installed to exclude normal IO requests.
1746 static sector_t
sync_request(mddev_t
*mddev
, sector_t sector_nr
, int *skipped
, int go_faster
)
1748 conf_t
*conf
= mddev
->private;
1751 sector_t max_sector
, nr_sectors
;
1755 int write_targets
= 0, read_targets
= 0;
1757 int still_degraded
= 0;
1759 if (!conf
->r1buf_pool
)
1760 if (init_resync(conf
))
1763 max_sector
= mddev
->dev_sectors
;
1764 if (sector_nr
>= max_sector
) {
1765 /* If we aborted, we need to abort the
1766 * sync on the 'current' bitmap chunk (there will
1767 * only be one in raid1 resync.
1768 * We can find the current addess in mddev->curr_resync
1770 if (mddev
->curr_resync
< max_sector
) /* aborted */
1771 bitmap_end_sync(mddev
->bitmap
, mddev
->curr_resync
,
1773 else /* completed sync */
1776 bitmap_close_sync(mddev
->bitmap
);
1781 if (mddev
->bitmap
== NULL
&&
1782 mddev
->recovery_cp
== MaxSector
&&
1783 !test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
) &&
1784 conf
->fullsync
== 0) {
1786 return max_sector
- sector_nr
;
1788 /* before building a request, check if we can skip these blocks..
1789 * This call the bitmap_start_sync doesn't actually record anything
1791 if (!bitmap_start_sync(mddev
->bitmap
, sector_nr
, &sync_blocks
, 1) &&
1792 !conf
->fullsync
&& !test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
)) {
1793 /* We can skip this block, and probably several more */
1798 * If there is non-resync activity waiting for a turn,
1799 * and resync is going fast enough,
1800 * then let it though before starting on this new sync request.
1802 if (!go_faster
&& conf
->nr_waiting
)
1803 msleep_interruptible(1000);
1805 bitmap_cond_end_sync(mddev
->bitmap
, sector_nr
);
1806 raise_barrier(conf
);
1808 conf
->next_resync
= sector_nr
;
1810 r1_bio
= mempool_alloc(conf
->r1buf_pool
, GFP_NOIO
);
1813 * If we get a correctably read error during resync or recovery,
1814 * we might want to read from a different device. So we
1815 * flag all drives that could conceivably be read from for READ,
1816 * and any others (which will be non-In_sync devices) for WRITE.
1817 * If a read fails, we try reading from something else for which READ
1821 r1_bio
->mddev
= mddev
;
1822 r1_bio
->sector
= sector_nr
;
1824 set_bit(R1BIO_IsSync
, &r1_bio
->state
);
1826 for (i
=0; i
< conf
->raid_disks
; i
++) {
1828 bio
= r1_bio
->bios
[i
];
1830 /* take from bio_init */
1831 bio
->bi_next
= NULL
;
1832 bio
->bi_flags
&= ~(BIO_POOL_MASK
-1);
1833 bio
->bi_flags
|= 1 << BIO_UPTODATE
;
1834 bio
->bi_comp_cpu
= -1;
1838 bio
->bi_phys_segments
= 0;
1840 bio
->bi_end_io
= NULL
;
1841 bio
->bi_private
= NULL
;
1843 rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
1845 test_bit(Faulty
, &rdev
->flags
)) {
1848 } else if (!test_bit(In_sync
, &rdev
->flags
)) {
1850 bio
->bi_end_io
= end_sync_write
;
1853 /* may need to read from here */
1855 bio
->bi_end_io
= end_sync_read
;
1856 if (test_bit(WriteMostly
, &rdev
->flags
)) {
1865 atomic_inc(&rdev
->nr_pending
);
1866 bio
->bi_sector
= sector_nr
+ rdev
->data_offset
;
1867 bio
->bi_bdev
= rdev
->bdev
;
1868 bio
->bi_private
= r1_bio
;
1873 r1_bio
->read_disk
= disk
;
1875 if (test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
) && read_targets
> 0)
1876 /* extra read targets are also write targets */
1877 write_targets
+= read_targets
-1;
1879 if (write_targets
== 0 || read_targets
== 0) {
1880 /* There is nowhere to write, so all non-sync
1881 * drives must be failed - so we are finished
1883 sector_t rv
= max_sector
- sector_nr
;
1889 if (max_sector
> mddev
->resync_max
)
1890 max_sector
= mddev
->resync_max
; /* Don't do IO beyond here */
1895 int len
= PAGE_SIZE
;
1896 if (sector_nr
+ (len
>>9) > max_sector
)
1897 len
= (max_sector
- sector_nr
) << 9;
1900 if (sync_blocks
== 0) {
1901 if (!bitmap_start_sync(mddev
->bitmap
, sector_nr
,
1902 &sync_blocks
, still_degraded
) &&
1904 !test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
))
1906 BUG_ON(sync_blocks
< (PAGE_SIZE
>>9));
1907 if ((len
>> 9) > sync_blocks
)
1908 len
= sync_blocks
<<9;
1911 for (i
=0 ; i
< conf
->raid_disks
; i
++) {
1912 bio
= r1_bio
->bios
[i
];
1913 if (bio
->bi_end_io
) {
1914 page
= bio
->bi_io_vec
[bio
->bi_vcnt
].bv_page
;
1915 if (bio_add_page(bio
, page
, len
, 0) == 0) {
1917 bio
->bi_io_vec
[bio
->bi_vcnt
].bv_page
= page
;
1920 bio
= r1_bio
->bios
[i
];
1921 if (bio
->bi_end_io
==NULL
)
1923 /* remove last page from this bio */
1925 bio
->bi_size
-= len
;
1926 bio
->bi_flags
&= ~(1<< BIO_SEG_VALID
);
1932 nr_sectors
+= len
>>9;
1933 sector_nr
+= len
>>9;
1934 sync_blocks
-= (len
>>9);
1935 } while (r1_bio
->bios
[disk
]->bi_vcnt
< RESYNC_PAGES
);
1937 r1_bio
->sectors
= nr_sectors
;
1939 /* For a user-requested sync, we read all readable devices and do a
1942 if (test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
)) {
1943 atomic_set(&r1_bio
->remaining
, read_targets
);
1944 for (i
=0; i
<conf
->raid_disks
; i
++) {
1945 bio
= r1_bio
->bios
[i
];
1946 if (bio
->bi_end_io
== end_sync_read
) {
1947 md_sync_acct(bio
->bi_bdev
, nr_sectors
);
1948 generic_make_request(bio
);
1952 atomic_set(&r1_bio
->remaining
, 1);
1953 bio
= r1_bio
->bios
[r1_bio
->read_disk
];
1954 md_sync_acct(bio
->bi_bdev
, nr_sectors
);
1955 generic_make_request(bio
);
1961 static sector_t
raid1_size(mddev_t
*mddev
, sector_t sectors
, int raid_disks
)
1966 return mddev
->dev_sectors
;
1969 static conf_t
*setup_conf(mddev_t
*mddev
)
1973 mirror_info_t
*disk
;
1977 conf
= kzalloc(sizeof(conf_t
), GFP_KERNEL
);
1981 conf
->mirrors
= kzalloc(sizeof(struct mirror_info
)*mddev
->raid_disks
,
1986 conf
->tmppage
= alloc_page(GFP_KERNEL
);
1990 conf
->poolinfo
= kzalloc(sizeof(*conf
->poolinfo
), GFP_KERNEL
);
1991 if (!conf
->poolinfo
)
1993 conf
->poolinfo
->raid_disks
= mddev
->raid_disks
;
1994 conf
->r1bio_pool
= mempool_create(NR_RAID1_BIOS
, r1bio_pool_alloc
,
1997 if (!conf
->r1bio_pool
)
2000 conf
->poolinfo
->mddev
= mddev
;
2002 spin_lock_init(&conf
->device_lock
);
2003 list_for_each_entry(rdev
, &mddev
->disks
, same_set
) {
2004 int disk_idx
= rdev
->raid_disk
;
2005 if (disk_idx
>= mddev
->raid_disks
2008 disk
= conf
->mirrors
+ disk_idx
;
2012 disk
->head_position
= 0;
2014 conf
->raid_disks
= mddev
->raid_disks
;
2015 conf
->mddev
= mddev
;
2016 INIT_LIST_HEAD(&conf
->retry_list
);
2018 spin_lock_init(&conf
->resync_lock
);
2019 init_waitqueue_head(&conf
->wait_barrier
);
2021 bio_list_init(&conf
->pending_bio_list
);
2022 bio_list_init(&conf
->flushing_bio_list
);
2024 conf
->last_used
= -1;
2025 for (i
= 0; i
< conf
->raid_disks
; i
++) {
2027 disk
= conf
->mirrors
+ i
;
2030 !test_bit(In_sync
, &disk
->rdev
->flags
)) {
2031 disk
->head_position
= 0;
2034 } else if (conf
->last_used
< 0)
2036 * The first working device is used as a
2037 * starting point to read balancing.
2039 conf
->last_used
= i
;
2043 if (conf
->last_used
< 0) {
2044 printk(KERN_ERR
"md/raid1:%s: no operational mirrors\n",
2049 conf
->thread
= md_register_thread(raid1d
, mddev
, NULL
);
2050 if (!conf
->thread
) {
2052 "md/raid1:%s: couldn't allocate thread\n",
2061 if (conf
->r1bio_pool
)
2062 mempool_destroy(conf
->r1bio_pool
);
2063 kfree(conf
->mirrors
);
2064 safe_put_page(conf
->tmppage
);
2065 kfree(conf
->poolinfo
);
2068 return ERR_PTR(err
);
2071 static int run(mddev_t
*mddev
)
2077 if (mddev
->level
!= 1) {
2078 printk(KERN_ERR
"md/raid1:%s: raid level not set to mirroring (%d)\n",
2079 mdname(mddev
), mddev
->level
);
2082 if (mddev
->reshape_position
!= MaxSector
) {
2083 printk(KERN_ERR
"md/raid1:%s: reshape_position set but not supported\n",
2088 * copy the already verified devices into our private RAID1
2089 * bookkeeping area. [whatever we allocate in run(),
2090 * should be freed in stop()]
2092 if (mddev
->private == NULL
)
2093 conf
= setup_conf(mddev
);
2095 conf
= mddev
->private;
2098 return PTR_ERR(conf
);
2100 mddev
->queue
->queue_lock
= &conf
->device_lock
;
2101 list_for_each_entry(rdev
, &mddev
->disks
, same_set
) {
2102 disk_stack_limits(mddev
->gendisk
, rdev
->bdev
,
2103 rdev
->data_offset
<< 9);
2104 /* as we don't honour merge_bvec_fn, we must never risk
2105 * violating it, so limit ->max_segments to 1 lying within
2106 * a single page, as a one page request is never in violation.
2108 if (rdev
->bdev
->bd_disk
->queue
->merge_bvec_fn
) {
2109 blk_queue_max_segments(mddev
->queue
, 1);
2110 blk_queue_segment_boundary(mddev
->queue
,
2111 PAGE_CACHE_SIZE
- 1);
2115 mddev
->degraded
= 0;
2116 for (i
=0; i
< conf
->raid_disks
; i
++)
2117 if (conf
->mirrors
[i
].rdev
== NULL
||
2118 !test_bit(In_sync
, &conf
->mirrors
[i
].rdev
->flags
) ||
2119 test_bit(Faulty
, &conf
->mirrors
[i
].rdev
->flags
))
2122 if (conf
->raid_disks
- mddev
->degraded
== 1)
2123 mddev
->recovery_cp
= MaxSector
;
2125 if (mddev
->recovery_cp
!= MaxSector
)
2126 printk(KERN_NOTICE
"md/raid1:%s: not clean"
2127 " -- starting background reconstruction\n",
2130 "md/raid1:%s: active with %d out of %d mirrors\n",
2131 mdname(mddev
), mddev
->raid_disks
- mddev
->degraded
,
2135 * Ok, everything is just fine now
2137 mddev
->thread
= conf
->thread
;
2138 conf
->thread
= NULL
;
2139 mddev
->private = conf
;
2141 md_set_array_sectors(mddev
, raid1_size(mddev
, 0, 0));
2143 mddev
->queue
->unplug_fn
= raid1_unplug
;
2144 mddev
->queue
->backing_dev_info
.congested_fn
= raid1_congested
;
2145 mddev
->queue
->backing_dev_info
.congested_data
= mddev
;
2146 md_integrity_register(mddev
);
2150 static int stop(mddev_t
*mddev
)
2152 conf_t
*conf
= mddev
->private;
2153 struct bitmap
*bitmap
= mddev
->bitmap
;
2155 /* wait for behind writes to complete */
2156 if (bitmap
&& atomic_read(&bitmap
->behind_writes
) > 0) {
2157 printk(KERN_INFO
"md/raid1:%s: behind writes in progress - waiting to stop.\n",
2159 /* need to kick something here to make sure I/O goes? */
2160 wait_event(bitmap
->behind_wait
,
2161 atomic_read(&bitmap
->behind_writes
) == 0);
2164 raise_barrier(conf
);
2165 lower_barrier(conf
);
2167 md_unregister_thread(mddev
->thread
);
2168 mddev
->thread
= NULL
;
2169 blk_sync_queue(mddev
->queue
); /* the unplug fn references 'conf'*/
2170 if (conf
->r1bio_pool
)
2171 mempool_destroy(conf
->r1bio_pool
);
2172 kfree(conf
->mirrors
);
2173 kfree(conf
->poolinfo
);
2175 mddev
->private = NULL
;
2179 static int raid1_resize(mddev_t
*mddev
, sector_t sectors
)
2181 /* no resync is happening, and there is enough space
2182 * on all devices, so we can resize.
2183 * We need to make sure resync covers any new space.
2184 * If the array is shrinking we should possibly wait until
2185 * any io in the removed space completes, but it hardly seems
2188 md_set_array_sectors(mddev
, raid1_size(mddev
, sectors
, 0));
2189 if (mddev
->array_sectors
> raid1_size(mddev
, sectors
, 0))
2191 set_capacity(mddev
->gendisk
, mddev
->array_sectors
);
2192 revalidate_disk(mddev
->gendisk
);
2193 if (sectors
> mddev
->dev_sectors
&&
2194 mddev
->recovery_cp
== MaxSector
) {
2195 mddev
->recovery_cp
= mddev
->dev_sectors
;
2196 set_bit(MD_RECOVERY_NEEDED
, &mddev
->recovery
);
2198 mddev
->dev_sectors
= sectors
;
2199 mddev
->resync_max_sectors
= sectors
;
2203 static int raid1_reshape(mddev_t
*mddev
)
2206 * 1/ resize the r1bio_pool
2207 * 2/ resize conf->mirrors
2209 * We allocate a new r1bio_pool if we can.
2210 * Then raise a device barrier and wait until all IO stops.
2211 * Then resize conf->mirrors and swap in the new r1bio pool.
2213 * At the same time, we "pack" the devices so that all the missing
2214 * devices have the higher raid_disk numbers.
2216 mempool_t
*newpool
, *oldpool
;
2217 struct pool_info
*newpoolinfo
;
2218 mirror_info_t
*newmirrors
;
2219 conf_t
*conf
= mddev
->private;
2220 int cnt
, raid_disks
;
2221 unsigned long flags
;
2224 /* Cannot change chunk_size, layout, or level */
2225 if (mddev
->chunk_sectors
!= mddev
->new_chunk_sectors
||
2226 mddev
->layout
!= mddev
->new_layout
||
2227 mddev
->level
!= mddev
->new_level
) {
2228 mddev
->new_chunk_sectors
= mddev
->chunk_sectors
;
2229 mddev
->new_layout
= mddev
->layout
;
2230 mddev
->new_level
= mddev
->level
;
2234 err
= md_allow_write(mddev
);
2238 raid_disks
= mddev
->raid_disks
+ mddev
->delta_disks
;
2240 if (raid_disks
< conf
->raid_disks
) {
2242 for (d
= 0; d
< conf
->raid_disks
; d
++)
2243 if (conf
->mirrors
[d
].rdev
)
2245 if (cnt
> raid_disks
)
2249 newpoolinfo
= kmalloc(sizeof(*newpoolinfo
), GFP_KERNEL
);
2252 newpoolinfo
->mddev
= mddev
;
2253 newpoolinfo
->raid_disks
= raid_disks
;
2255 newpool
= mempool_create(NR_RAID1_BIOS
, r1bio_pool_alloc
,
2256 r1bio_pool_free
, newpoolinfo
);
2261 newmirrors
= kzalloc(sizeof(struct mirror_info
) * raid_disks
, GFP_KERNEL
);
2264 mempool_destroy(newpool
);
2268 raise_barrier(conf
);
2270 /* ok, everything is stopped */
2271 oldpool
= conf
->r1bio_pool
;
2272 conf
->r1bio_pool
= newpool
;
2274 for (d
= d2
= 0; d
< conf
->raid_disks
; d
++) {
2275 mdk_rdev_t
*rdev
= conf
->mirrors
[d
].rdev
;
2276 if (rdev
&& rdev
->raid_disk
!= d2
) {
2278 sprintf(nm
, "rd%d", rdev
->raid_disk
);
2279 sysfs_remove_link(&mddev
->kobj
, nm
);
2280 rdev
->raid_disk
= d2
;
2281 sprintf(nm
, "rd%d", rdev
->raid_disk
);
2282 sysfs_remove_link(&mddev
->kobj
, nm
);
2283 if (sysfs_create_link(&mddev
->kobj
,
2286 "md/raid1:%s: cannot register "
2291 newmirrors
[d2
++].rdev
= rdev
;
2293 kfree(conf
->mirrors
);
2294 conf
->mirrors
= newmirrors
;
2295 kfree(conf
->poolinfo
);
2296 conf
->poolinfo
= newpoolinfo
;
2298 spin_lock_irqsave(&conf
->device_lock
, flags
);
2299 mddev
->degraded
+= (raid_disks
- conf
->raid_disks
);
2300 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
2301 conf
->raid_disks
= mddev
->raid_disks
= raid_disks
;
2302 mddev
->delta_disks
= 0;
2304 conf
->last_used
= 0; /* just make sure it is in-range */
2305 lower_barrier(conf
);
2307 set_bit(MD_RECOVERY_NEEDED
, &mddev
->recovery
);
2308 md_wakeup_thread(mddev
->thread
);
2310 mempool_destroy(oldpool
);
2314 static void raid1_quiesce(mddev_t
*mddev
, int state
)
2316 conf_t
*conf
= mddev
->private;
2319 case 2: /* wake for suspend */
2320 wake_up(&conf
->wait_barrier
);
2323 raise_barrier(conf
);
2326 lower_barrier(conf
);
2331 static void *raid1_takeover(mddev_t
*mddev
)
2333 /* raid1 can take over:
2334 * raid5 with 2 devices, any layout or chunk size
2336 if (mddev
->level
== 5 && mddev
->raid_disks
== 2) {
2338 mddev
->new_level
= 1;
2339 mddev
->new_layout
= 0;
2340 mddev
->new_chunk_sectors
= 0;
2341 conf
= setup_conf(mddev
);
2346 return ERR_PTR(-EINVAL
);
2349 static struct mdk_personality raid1_personality
=
2353 .owner
= THIS_MODULE
,
2354 .make_request
= make_request
,
2358 .error_handler
= error
,
2359 .hot_add_disk
= raid1_add_disk
,
2360 .hot_remove_disk
= raid1_remove_disk
,
2361 .spare_active
= raid1_spare_active
,
2362 .sync_request
= sync_request
,
2363 .resize
= raid1_resize
,
2365 .check_reshape
= raid1_reshape
,
2366 .quiesce
= raid1_quiesce
,
2367 .takeover
= raid1_takeover
,
2370 static int __init
raid_init(void)
2372 return register_md_personality(&raid1_personality
);
2375 static void raid_exit(void)
2377 unregister_md_personality(&raid1_personality
);
2380 module_init(raid_init
);
2381 module_exit(raid_exit
);
2382 MODULE_LICENSE("GPL");
2383 MODULE_DESCRIPTION("RAID1 (mirroring) personality for MD");
2384 MODULE_ALIAS("md-personality-3"); /* RAID1 */
2385 MODULE_ALIAS("md-raid1");
2386 MODULE_ALIAS("md-level-1");