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
= (r1bio_t
*)(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
"raid1: %s: rescheduling sector %llu\n",
301 bdevname(conf
->mirrors
[mirror
].rdev
->bdev
,b
), (unsigned long long)r1_bio
->sector
);
302 reschedule_retry(r1_bio
);
305 rdev_dec_pending(conf
->mirrors
[mirror
].rdev
, conf
->mddev
);
308 static void raid1_end_write_request(struct bio
*bio
, int error
)
310 int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
311 r1bio_t
* r1_bio
= (r1bio_t
*)(bio
->bi_private
);
312 int mirror
, behind
= test_bit(R1BIO_BehindIO
, &r1_bio
->state
);
313 conf_t
*conf
= r1_bio
->mddev
->private;
314 struct bio
*to_put
= NULL
;
317 for (mirror
= 0; mirror
< conf
->raid_disks
; mirror
++)
318 if (r1_bio
->bios
[mirror
] == bio
)
321 if (error
== -EOPNOTSUPP
&& test_bit(R1BIO_Barrier
, &r1_bio
->state
)) {
322 set_bit(BarriersNotsupp
, &conf
->mirrors
[mirror
].rdev
->flags
);
323 set_bit(R1BIO_BarrierRetry
, &r1_bio
->state
);
324 r1_bio
->mddev
->barriers_work
= 0;
325 /* Don't rdev_dec_pending in this branch - keep it for the retry */
328 * this branch is our 'one mirror IO has finished' event handler:
330 r1_bio
->bios
[mirror
] = NULL
;
333 md_error(r1_bio
->mddev
, conf
->mirrors
[mirror
].rdev
);
334 /* an I/O failed, we can't clear the bitmap */
335 set_bit(R1BIO_Degraded
, &r1_bio
->state
);
338 * Set R1BIO_Uptodate in our master bio, so that
339 * we will return a good error code for to the higher
340 * levels even if IO on some other mirrored buffer fails.
342 * The 'master' represents the composite IO operation to
343 * user-side. So if something waits for IO, then it will
344 * wait for the 'master' bio.
346 set_bit(R1BIO_Uptodate
, &r1_bio
->state
);
348 update_head_pos(mirror
, r1_bio
);
351 if (test_bit(WriteMostly
, &conf
->mirrors
[mirror
].rdev
->flags
))
352 atomic_dec(&r1_bio
->behind_remaining
);
354 /* In behind mode, we ACK the master bio once the I/O has safely
355 * reached all non-writemostly disks. Setting the Returned bit
356 * ensures that this gets done only once -- we don't ever want to
357 * return -EIO here, instead we'll wait */
359 if (atomic_read(&r1_bio
->behind_remaining
) >= (atomic_read(&r1_bio
->remaining
)-1) &&
360 test_bit(R1BIO_Uptodate
, &r1_bio
->state
)) {
361 /* Maybe we can return now */
362 if (!test_and_set_bit(R1BIO_Returned
, &r1_bio
->state
)) {
363 struct bio
*mbio
= r1_bio
->master_bio
;
364 PRINTK(KERN_DEBUG
"raid1: behind end write sectors %llu-%llu\n",
365 (unsigned long long) mbio
->bi_sector
,
366 (unsigned long long) mbio
->bi_sector
+
367 (mbio
->bi_size
>> 9) - 1);
372 rdev_dec_pending(conf
->mirrors
[mirror
].rdev
, conf
->mddev
);
376 * Let's see if all mirrored write operations have finished
379 if (atomic_dec_and_test(&r1_bio
->remaining
)) {
380 if (test_bit(R1BIO_BarrierRetry
, &r1_bio
->state
))
381 reschedule_retry(r1_bio
);
383 /* it really is the end of this request */
384 if (test_bit(R1BIO_BehindIO
, &r1_bio
->state
)) {
385 /* free extra copy of the data pages */
386 int i
= bio
->bi_vcnt
;
388 safe_put_page(bio
->bi_io_vec
[i
].bv_page
);
390 /* clear the bitmap if all writes complete successfully */
391 bitmap_endwrite(r1_bio
->mddev
->bitmap
, r1_bio
->sector
,
393 !test_bit(R1BIO_Degraded
, &r1_bio
->state
),
395 md_write_end(r1_bio
->mddev
);
396 raid_end_bio_io(r1_bio
);
406 * This routine returns the disk from which the requested read should
407 * be done. There is a per-array 'next expected sequential IO' sector
408 * number - if this matches on the next IO then we use the last disk.
409 * There is also a per-disk 'last know head position' sector that is
410 * maintained from IRQ contexts, both the normal and the resync IO
411 * completion handlers update this position correctly. If there is no
412 * perfect sequential match then we pick the disk whose head is closest.
414 * If there are 2 mirrors in the same 2 devices, performance degrades
415 * because position is mirror, not device based.
417 * The rdev for the device selected will have nr_pending incremented.
419 static int read_balance(conf_t
*conf
, r1bio_t
*r1_bio
)
421 const unsigned long this_sector
= r1_bio
->sector
;
422 int new_disk
= conf
->last_used
, disk
= new_disk
;
424 const int sectors
= r1_bio
->sectors
;
425 sector_t new_distance
, current_distance
;
430 * Check if we can balance. We can balance on the whole
431 * device if no resync is going on, or below the resync window.
432 * We take the first readable disk when above the resync window.
435 if (conf
->mddev
->recovery_cp
< MaxSector
&&
436 (this_sector
+ sectors
>= conf
->next_resync
)) {
437 /* Choose the first operation device, for consistancy */
440 for (rdev
= rcu_dereference(conf
->mirrors
[new_disk
].rdev
);
441 r1_bio
->bios
[new_disk
] == IO_BLOCKED
||
442 !rdev
|| !test_bit(In_sync
, &rdev
->flags
)
443 || test_bit(WriteMostly
, &rdev
->flags
);
444 rdev
= rcu_dereference(conf
->mirrors
[++new_disk
].rdev
)) {
446 if (rdev
&& test_bit(In_sync
, &rdev
->flags
) &&
447 r1_bio
->bios
[new_disk
] != IO_BLOCKED
)
448 wonly_disk
= new_disk
;
450 if (new_disk
== conf
->raid_disks
- 1) {
451 new_disk
= wonly_disk
;
459 /* make sure the disk is operational */
460 for (rdev
= rcu_dereference(conf
->mirrors
[new_disk
].rdev
);
461 r1_bio
->bios
[new_disk
] == IO_BLOCKED
||
462 !rdev
|| !test_bit(In_sync
, &rdev
->flags
) ||
463 test_bit(WriteMostly
, &rdev
->flags
);
464 rdev
= rcu_dereference(conf
->mirrors
[new_disk
].rdev
)) {
466 if (rdev
&& test_bit(In_sync
, &rdev
->flags
) &&
467 r1_bio
->bios
[new_disk
] != IO_BLOCKED
)
468 wonly_disk
= new_disk
;
471 new_disk
= conf
->raid_disks
;
473 if (new_disk
== disk
) {
474 new_disk
= wonly_disk
;
483 /* now disk == new_disk == starting point for search */
486 * Don't change to another disk for sequential reads:
488 if (conf
->next_seq_sect
== this_sector
)
490 if (this_sector
== conf
->mirrors
[new_disk
].head_position
)
493 current_distance
= abs(this_sector
- conf
->mirrors
[disk
].head_position
);
495 /* Find the disk whose head is closest */
499 disk
= conf
->raid_disks
;
502 rdev
= rcu_dereference(conf
->mirrors
[disk
].rdev
);
504 if (!rdev
|| r1_bio
->bios
[disk
] == IO_BLOCKED
||
505 !test_bit(In_sync
, &rdev
->flags
) ||
506 test_bit(WriteMostly
, &rdev
->flags
))
509 if (!atomic_read(&rdev
->nr_pending
)) {
513 new_distance
= abs(this_sector
- conf
->mirrors
[disk
].head_position
);
514 if (new_distance
< current_distance
) {
515 current_distance
= new_distance
;
518 } while (disk
!= conf
->last_used
);
524 rdev
= rcu_dereference(conf
->mirrors
[new_disk
].rdev
);
527 atomic_inc(&rdev
->nr_pending
);
528 if (!test_bit(In_sync
, &rdev
->flags
)) {
529 /* cannot risk returning a device that failed
530 * before we inc'ed nr_pending
532 rdev_dec_pending(rdev
, conf
->mddev
);
535 conf
->next_seq_sect
= this_sector
+ sectors
;
536 conf
->last_used
= new_disk
;
543 static void unplug_slaves(mddev_t
*mddev
)
545 conf_t
*conf
= mddev
->private;
549 for (i
=0; i
<mddev
->raid_disks
; i
++) {
550 mdk_rdev_t
*rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
551 if (rdev
&& !test_bit(Faulty
, &rdev
->flags
) && atomic_read(&rdev
->nr_pending
)) {
552 struct request_queue
*r_queue
= bdev_get_queue(rdev
->bdev
);
554 atomic_inc(&rdev
->nr_pending
);
559 rdev_dec_pending(rdev
, mddev
);
566 static void raid1_unplug(struct request_queue
*q
)
568 mddev_t
*mddev
= q
->queuedata
;
570 unplug_slaves(mddev
);
571 md_wakeup_thread(mddev
->thread
);
574 static int raid1_congested(void *data
, int bits
)
576 mddev_t
*mddev
= data
;
577 conf_t
*conf
= mddev
->private;
580 if (mddev_congested(mddev
, bits
))
584 for (i
= 0; i
< mddev
->raid_disks
; i
++) {
585 mdk_rdev_t
*rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
586 if (rdev
&& !test_bit(Faulty
, &rdev
->flags
)) {
587 struct request_queue
*q
= bdev_get_queue(rdev
->bdev
);
589 /* Note the '|| 1' - when read_balance prefers
590 * non-congested targets, it can be removed
592 if ((bits
& (1<<BDI_async_congested
)) || 1)
593 ret
|= bdi_congested(&q
->backing_dev_info
, bits
);
595 ret
&= bdi_congested(&q
->backing_dev_info
, bits
);
603 static int flush_pending_writes(conf_t
*conf
)
605 /* Any writes that have been queued but are awaiting
606 * bitmap updates get flushed here.
607 * We return 1 if any requests were actually submitted.
611 spin_lock_irq(&conf
->device_lock
);
613 if (conf
->pending_bio_list
.head
) {
615 bio
= bio_list_get(&conf
->pending_bio_list
);
616 blk_remove_plug(conf
->mddev
->queue
);
617 spin_unlock_irq(&conf
->device_lock
);
618 /* flush any pending bitmap writes to
619 * disk before proceeding w/ I/O */
620 bitmap_unplug(conf
->mddev
->bitmap
);
622 while (bio
) { /* submit pending writes */
623 struct bio
*next
= bio
->bi_next
;
625 generic_make_request(bio
);
630 spin_unlock_irq(&conf
->device_lock
);
635 * Sometimes we need to suspend IO while we do something else,
636 * either some resync/recovery, or reconfigure the array.
637 * To do this we raise a 'barrier'.
638 * The 'barrier' is a counter that can be raised multiple times
639 * to count how many activities are happening which preclude
641 * We can only raise the barrier if there is no pending IO.
642 * i.e. if nr_pending == 0.
643 * We choose only to raise the barrier if no-one is waiting for the
644 * barrier to go down. This means that as soon as an IO request
645 * is ready, no other operations which require a barrier will start
646 * until the IO request has had a chance.
648 * So: regular IO calls 'wait_barrier'. When that returns there
649 * is no backgroup IO happening, It must arrange to call
650 * allow_barrier when it has finished its IO.
651 * backgroup IO calls must call raise_barrier. Once that returns
652 * there is no normal IO happeing. It must arrange to call
653 * lower_barrier when the particular background IO completes.
655 #define RESYNC_DEPTH 32
657 static void raise_barrier(conf_t
*conf
)
659 spin_lock_irq(&conf
->resync_lock
);
661 /* Wait until no block IO is waiting */
662 wait_event_lock_irq(conf
->wait_barrier
, !conf
->nr_waiting
,
664 raid1_unplug(conf
->mddev
->queue
));
666 /* block any new IO from starting */
669 /* No wait for all pending IO to complete */
670 wait_event_lock_irq(conf
->wait_barrier
,
671 !conf
->nr_pending
&& conf
->barrier
< RESYNC_DEPTH
,
673 raid1_unplug(conf
->mddev
->queue
));
675 spin_unlock_irq(&conf
->resync_lock
);
678 static void lower_barrier(conf_t
*conf
)
681 BUG_ON(conf
->barrier
<= 0);
682 spin_lock_irqsave(&conf
->resync_lock
, flags
);
684 spin_unlock_irqrestore(&conf
->resync_lock
, flags
);
685 wake_up(&conf
->wait_barrier
);
688 static void wait_barrier(conf_t
*conf
)
690 spin_lock_irq(&conf
->resync_lock
);
693 wait_event_lock_irq(conf
->wait_barrier
, !conf
->barrier
,
695 raid1_unplug(conf
->mddev
->queue
));
699 spin_unlock_irq(&conf
->resync_lock
);
702 static void allow_barrier(conf_t
*conf
)
705 spin_lock_irqsave(&conf
->resync_lock
, flags
);
707 spin_unlock_irqrestore(&conf
->resync_lock
, flags
);
708 wake_up(&conf
->wait_barrier
);
711 static void freeze_array(conf_t
*conf
)
713 /* stop syncio and normal IO and wait for everything to
715 * We increment barrier and nr_waiting, and then
716 * wait until nr_pending match nr_queued+1
717 * This is called in the context of one normal IO request
718 * that has failed. Thus any sync request that might be pending
719 * will be blocked by nr_pending, and we need to wait for
720 * pending IO requests to complete or be queued for re-try.
721 * Thus the number queued (nr_queued) plus this request (1)
722 * must match the number of pending IOs (nr_pending) before
725 spin_lock_irq(&conf
->resync_lock
);
728 wait_event_lock_irq(conf
->wait_barrier
,
729 conf
->nr_pending
== conf
->nr_queued
+1,
731 ({ flush_pending_writes(conf
);
732 raid1_unplug(conf
->mddev
->queue
); }));
733 spin_unlock_irq(&conf
->resync_lock
);
735 static void unfreeze_array(conf_t
*conf
)
737 /* reverse the effect of the freeze */
738 spin_lock_irq(&conf
->resync_lock
);
741 wake_up(&conf
->wait_barrier
);
742 spin_unlock_irq(&conf
->resync_lock
);
746 /* duplicate the data pages for behind I/O */
747 static struct page
**alloc_behind_pages(struct bio
*bio
)
750 struct bio_vec
*bvec
;
751 struct page
**pages
= kzalloc(bio
->bi_vcnt
* sizeof(struct page
*),
753 if (unlikely(!pages
))
756 bio_for_each_segment(bvec
, bio
, i
) {
757 pages
[i
] = alloc_page(GFP_NOIO
);
758 if (unlikely(!pages
[i
]))
760 memcpy(kmap(pages
[i
]) + bvec
->bv_offset
,
761 kmap(bvec
->bv_page
) + bvec
->bv_offset
, bvec
->bv_len
);
763 kunmap(bvec
->bv_page
);
770 for (i
= 0; i
< bio
->bi_vcnt
&& pages
[i
]; i
++)
773 PRINTK("%dB behind alloc failed, doing sync I/O\n", bio
->bi_size
);
777 static int make_request(struct request_queue
*q
, struct bio
* bio
)
779 mddev_t
*mddev
= q
->queuedata
;
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 bool do_sync
= bio_rw_flagged(bio
, BIO_RW_SYNCIO
);
793 mdk_rdev_t
*blocked_rdev
;
796 * Register the new request and wait if the reconstruction
797 * thread has put up a bar for new requests.
798 * Continue immediately if no resync is active currently.
799 * We test barriers_work *after* md_write_start as md_write_start
800 * may cause the first superblock write, and that will check out
804 md_write_start(mddev
, bio
); /* wait on superblock update early */
806 if (bio_data_dir(bio
) == WRITE
&&
807 bio
->bi_sector
+ bio
->bi_size
/512 > mddev
->suspend_lo
&&
808 bio
->bi_sector
< mddev
->suspend_hi
) {
809 /* As the suspend_* range is controlled by
810 * userspace, we want an interruptible
815 flush_signals(current
);
816 prepare_to_wait(&conf
->wait_barrier
,
817 &w
, TASK_INTERRUPTIBLE
);
818 if (bio
->bi_sector
+ bio
->bi_size
/512 <= mddev
->suspend_lo
||
819 bio
->bi_sector
>= mddev
->suspend_hi
)
823 finish_wait(&conf
->wait_barrier
, &w
);
825 if (unlikely(!mddev
->barriers_work
&&
826 bio_rw_flagged(bio
, BIO_RW_BARRIER
))) {
829 bio_endio(bio
, -EOPNOTSUPP
);
835 bitmap
= mddev
->bitmap
;
837 cpu
= part_stat_lock();
838 part_stat_inc(cpu
, &mddev
->gendisk
->part0
, ios
[rw
]);
839 part_stat_add(cpu
, &mddev
->gendisk
->part0
, sectors
[rw
],
844 * make_request() can abort the operation when READA is being
845 * used and no empty request is available.
848 r1_bio
= mempool_alloc(conf
->r1bio_pool
, GFP_NOIO
);
850 r1_bio
->master_bio
= bio
;
851 r1_bio
->sectors
= bio
->bi_size
>> 9;
853 r1_bio
->mddev
= mddev
;
854 r1_bio
->sector
= bio
->bi_sector
;
858 * read balancing logic:
860 int rdisk
= read_balance(conf
, r1_bio
);
863 /* couldn't find anywhere to read from */
864 raid_end_bio_io(r1_bio
);
867 mirror
= conf
->mirrors
+ rdisk
;
869 r1_bio
->read_disk
= rdisk
;
871 read_bio
= bio_clone(bio
, GFP_NOIO
);
873 r1_bio
->bios
[rdisk
] = read_bio
;
875 read_bio
->bi_sector
= r1_bio
->sector
+ mirror
->rdev
->data_offset
;
876 read_bio
->bi_bdev
= mirror
->rdev
->bdev
;
877 read_bio
->bi_end_io
= raid1_end_read_request
;
878 read_bio
->bi_rw
= READ
| (do_sync
<< BIO_RW_SYNCIO
);
879 read_bio
->bi_private
= r1_bio
;
881 generic_make_request(read_bio
);
888 /* first select target devices under spinlock and
889 * inc refcount on their rdev. Record them by setting
892 disks
= conf
->raid_disks
;
894 { static int first
=1;
895 if (first
) printk("First Write sector %llu disks %d\n",
896 (unsigned long long)r1_bio
->sector
, disks
);
903 for (i
= 0; i
< disks
; i
++) {
904 mdk_rdev_t
*rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
905 if (rdev
&& unlikely(test_bit(Blocked
, &rdev
->flags
))) {
906 atomic_inc(&rdev
->nr_pending
);
910 if (rdev
&& !test_bit(Faulty
, &rdev
->flags
)) {
911 atomic_inc(&rdev
->nr_pending
);
912 if (test_bit(Faulty
, &rdev
->flags
)) {
913 rdev_dec_pending(rdev
, mddev
);
914 r1_bio
->bios
[i
] = NULL
;
916 r1_bio
->bios
[i
] = bio
;
920 r1_bio
->bios
[i
] = NULL
;
924 if (unlikely(blocked_rdev
)) {
925 /* Wait for this device to become unblocked */
928 for (j
= 0; j
< i
; j
++)
930 rdev_dec_pending(conf
->mirrors
[j
].rdev
, mddev
);
933 md_wait_for_blocked_rdev(blocked_rdev
, mddev
);
938 BUG_ON(targets
== 0); /* we never fail the last device */
940 if (targets
< conf
->raid_disks
) {
941 /* array is degraded, we will not clear the bitmap
942 * on I/O completion (see raid1_end_write_request) */
943 set_bit(R1BIO_Degraded
, &r1_bio
->state
);
946 /* do behind I/O ? */
948 (atomic_read(&bitmap
->behind_writes
)
949 < mddev
->bitmap_info
.max_write_behind
) &&
950 (behind_pages
= alloc_behind_pages(bio
)) != NULL
)
951 set_bit(R1BIO_BehindIO
, &r1_bio
->state
);
953 atomic_set(&r1_bio
->remaining
, 0);
954 atomic_set(&r1_bio
->behind_remaining
, 0);
956 do_barriers
= bio_rw_flagged(bio
, BIO_RW_BARRIER
);
958 set_bit(R1BIO_Barrier
, &r1_bio
->state
);
961 for (i
= 0; i
< disks
; i
++) {
963 if (!r1_bio
->bios
[i
])
966 mbio
= bio_clone(bio
, GFP_NOIO
);
967 r1_bio
->bios
[i
] = mbio
;
969 mbio
->bi_sector
= r1_bio
->sector
+ conf
->mirrors
[i
].rdev
->data_offset
;
970 mbio
->bi_bdev
= conf
->mirrors
[i
].rdev
->bdev
;
971 mbio
->bi_end_io
= raid1_end_write_request
;
972 mbio
->bi_rw
= WRITE
| (do_barriers
<< BIO_RW_BARRIER
) |
973 (do_sync
<< BIO_RW_SYNCIO
);
974 mbio
->bi_private
= r1_bio
;
977 struct bio_vec
*bvec
;
980 /* Yes, I really want the '__' version so that
981 * we clear any unused pointer in the io_vec, rather
982 * than leave them unchanged. This is important
983 * because when we come to free the pages, we won't
984 * know the originial bi_idx, so we just free
987 __bio_for_each_segment(bvec
, mbio
, j
, 0)
988 bvec
->bv_page
= behind_pages
[j
];
989 if (test_bit(WriteMostly
, &conf
->mirrors
[i
].rdev
->flags
))
990 atomic_inc(&r1_bio
->behind_remaining
);
993 atomic_inc(&r1_bio
->remaining
);
995 bio_list_add(&bl
, mbio
);
997 kfree(behind_pages
); /* the behind pages are attached to the bios now */
999 bitmap_startwrite(bitmap
, bio
->bi_sector
, r1_bio
->sectors
,
1000 test_bit(R1BIO_BehindIO
, &r1_bio
->state
));
1001 spin_lock_irqsave(&conf
->device_lock
, flags
);
1002 bio_list_merge(&conf
->pending_bio_list
, &bl
);
1005 blk_plug_device(mddev
->queue
);
1006 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
1008 /* In case raid1d snuck into freeze_array */
1009 wake_up(&conf
->wait_barrier
);
1012 md_wakeup_thread(mddev
->thread
);
1014 while ((bio
= bio_list_pop(&bl
)) != NULL
)
1015 generic_make_request(bio
);
1021 static void status(struct seq_file
*seq
, mddev_t
*mddev
)
1023 conf_t
*conf
= mddev
->private;
1026 seq_printf(seq
, " [%d/%d] [", conf
->raid_disks
,
1027 conf
->raid_disks
- mddev
->degraded
);
1029 for (i
= 0; i
< conf
->raid_disks
; i
++) {
1030 mdk_rdev_t
*rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
1031 seq_printf(seq
, "%s",
1032 rdev
&& test_bit(In_sync
, &rdev
->flags
) ? "U" : "_");
1035 seq_printf(seq
, "]");
1039 static void error(mddev_t
*mddev
, mdk_rdev_t
*rdev
)
1041 char b
[BDEVNAME_SIZE
];
1042 conf_t
*conf
= mddev
->private;
1045 * If it is not operational, then we have already marked it as dead
1046 * else if it is the last working disks, ignore the error, let the
1047 * next level up know.
1048 * else mark the drive as failed
1050 if (test_bit(In_sync
, &rdev
->flags
)
1051 && (conf
->raid_disks
- mddev
->degraded
) == 1) {
1053 * Don't fail the drive, act as though we were just a
1054 * normal single drive.
1055 * However don't try a recovery from this drive as
1056 * it is very likely to fail.
1058 mddev
->recovery_disabled
= 1;
1061 if (test_and_clear_bit(In_sync
, &rdev
->flags
)) {
1062 unsigned long flags
;
1063 spin_lock_irqsave(&conf
->device_lock
, flags
);
1065 set_bit(Faulty
, &rdev
->flags
);
1066 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
1068 * if recovery is running, make sure it aborts.
1070 set_bit(MD_RECOVERY_INTR
, &mddev
->recovery
);
1072 set_bit(Faulty
, &rdev
->flags
);
1073 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
1074 printk(KERN_ALERT
"raid1: Disk failure on %s, disabling device.\n"
1075 "raid1: Operation continuing on %d devices.\n",
1076 bdevname(rdev
->bdev
,b
), conf
->raid_disks
- mddev
->degraded
);
1079 static void print_conf(conf_t
*conf
)
1083 printk("RAID1 conf printout:\n");
1085 printk("(!conf)\n");
1088 printk(" --- wd:%d rd:%d\n", conf
->raid_disks
- conf
->mddev
->degraded
,
1092 for (i
= 0; i
< conf
->raid_disks
; i
++) {
1093 char b
[BDEVNAME_SIZE
];
1094 mdk_rdev_t
*rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
1096 printk(" disk %d, wo:%d, o:%d, dev:%s\n",
1097 i
, !test_bit(In_sync
, &rdev
->flags
),
1098 !test_bit(Faulty
, &rdev
->flags
),
1099 bdevname(rdev
->bdev
,b
));
1104 static void close_sync(conf_t
*conf
)
1107 allow_barrier(conf
);
1109 mempool_destroy(conf
->r1buf_pool
);
1110 conf
->r1buf_pool
= NULL
;
1113 static int raid1_spare_active(mddev_t
*mddev
)
1116 conf_t
*conf
= mddev
->private;
1119 * Find all failed disks within the RAID1 configuration
1120 * and mark them readable.
1121 * Called under mddev lock, so rcu protection not needed.
1123 for (i
= 0; i
< conf
->raid_disks
; i
++) {
1124 mdk_rdev_t
*rdev
= conf
->mirrors
[i
].rdev
;
1126 && !test_bit(Faulty
, &rdev
->flags
)
1127 && !test_and_set_bit(In_sync
, &rdev
->flags
)) {
1128 unsigned long flags
;
1129 spin_lock_irqsave(&conf
->device_lock
, flags
);
1131 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
1140 static int raid1_add_disk(mddev_t
*mddev
, mdk_rdev_t
*rdev
)
1142 conf_t
*conf
= mddev
->private;
1147 int last
= mddev
->raid_disks
- 1;
1149 if (rdev
->raid_disk
>= 0)
1150 first
= last
= rdev
->raid_disk
;
1152 for (mirror
= first
; mirror
<= last
; mirror
++)
1153 if ( !(p
=conf
->mirrors
+mirror
)->rdev
) {
1155 disk_stack_limits(mddev
->gendisk
, rdev
->bdev
,
1156 rdev
->data_offset
<< 9);
1157 /* as we don't honour merge_bvec_fn, we must
1158 * never risk violating it, so limit
1159 * ->max_segments to one lying with a single
1160 * page, as a one page request is never in
1163 if (rdev
->bdev
->bd_disk
->queue
->merge_bvec_fn
) {
1164 blk_queue_max_segments(mddev
->queue
, 1);
1165 blk_queue_segment_boundary(mddev
->queue
,
1166 PAGE_CACHE_SIZE
- 1);
1169 p
->head_position
= 0;
1170 rdev
->raid_disk
= mirror
;
1172 /* As all devices are equivalent, we don't need a full recovery
1173 * if this was recently any drive of the array
1175 if (rdev
->saved_raid_disk
< 0)
1177 rcu_assign_pointer(p
->rdev
, rdev
);
1180 md_integrity_add_rdev(rdev
, mddev
);
1185 static int raid1_remove_disk(mddev_t
*mddev
, int number
)
1187 conf_t
*conf
= mddev
->private;
1190 mirror_info_t
*p
= conf
->mirrors
+ number
;
1195 if (test_bit(In_sync
, &rdev
->flags
) ||
1196 atomic_read(&rdev
->nr_pending
)) {
1200 /* Only remove non-faulty devices is recovery
1203 if (!test_bit(Faulty
, &rdev
->flags
) &&
1204 mddev
->degraded
< conf
->raid_disks
) {
1210 if (atomic_read(&rdev
->nr_pending
)) {
1211 /* lost the race, try later */
1216 md_integrity_register(mddev
);
1225 static void end_sync_read(struct bio
*bio
, int error
)
1227 r1bio_t
* r1_bio
= (r1bio_t
*)(bio
->bi_private
);
1230 for (i
=r1_bio
->mddev
->raid_disks
; i
--; )
1231 if (r1_bio
->bios
[i
] == bio
)
1234 update_head_pos(i
, r1_bio
);
1236 * we have read a block, now it needs to be re-written,
1237 * or re-read if the read failed.
1238 * We don't do much here, just schedule handling by raid1d
1240 if (test_bit(BIO_UPTODATE
, &bio
->bi_flags
))
1241 set_bit(R1BIO_Uptodate
, &r1_bio
->state
);
1243 if (atomic_dec_and_test(&r1_bio
->remaining
))
1244 reschedule_retry(r1_bio
);
1247 static void end_sync_write(struct bio
*bio
, int error
)
1249 int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
1250 r1bio_t
* r1_bio
= (r1bio_t
*)(bio
->bi_private
);
1251 mddev_t
*mddev
= r1_bio
->mddev
;
1252 conf_t
*conf
= mddev
->private;
1256 for (i
= 0; i
< conf
->raid_disks
; i
++)
1257 if (r1_bio
->bios
[i
] == bio
) {
1262 int sync_blocks
= 0;
1263 sector_t s
= r1_bio
->sector
;
1264 long sectors_to_go
= r1_bio
->sectors
;
1265 /* make sure these bits doesn't get cleared. */
1267 bitmap_end_sync(mddev
->bitmap
, s
,
1270 sectors_to_go
-= sync_blocks
;
1271 } while (sectors_to_go
> 0);
1272 md_error(mddev
, conf
->mirrors
[mirror
].rdev
);
1275 update_head_pos(mirror
, r1_bio
);
1277 if (atomic_dec_and_test(&r1_bio
->remaining
)) {
1278 sector_t s
= r1_bio
->sectors
;
1280 md_done_sync(mddev
, s
, uptodate
);
1284 static void sync_request_write(mddev_t
*mddev
, r1bio_t
*r1_bio
)
1286 conf_t
*conf
= mddev
->private;
1288 int disks
= conf
->raid_disks
;
1289 struct bio
*bio
, *wbio
;
1291 bio
= r1_bio
->bios
[r1_bio
->read_disk
];
1294 if (test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
)) {
1295 /* We have read all readable devices. If we haven't
1296 * got the block, then there is no hope left.
1297 * If we have, then we want to do a comparison
1298 * and skip the write if everything is the same.
1299 * If any blocks failed to read, then we need to
1300 * attempt an over-write
1303 if (!test_bit(R1BIO_Uptodate
, &r1_bio
->state
)) {
1304 for (i
=0; i
<mddev
->raid_disks
; i
++)
1305 if (r1_bio
->bios
[i
]->bi_end_io
== end_sync_read
)
1306 md_error(mddev
, conf
->mirrors
[i
].rdev
);
1308 md_done_sync(mddev
, r1_bio
->sectors
, 1);
1312 for (primary
=0; primary
<mddev
->raid_disks
; primary
++)
1313 if (r1_bio
->bios
[primary
]->bi_end_io
== end_sync_read
&&
1314 test_bit(BIO_UPTODATE
, &r1_bio
->bios
[primary
]->bi_flags
)) {
1315 r1_bio
->bios
[primary
]->bi_end_io
= NULL
;
1316 rdev_dec_pending(conf
->mirrors
[primary
].rdev
, mddev
);
1319 r1_bio
->read_disk
= primary
;
1320 for (i
=0; i
<mddev
->raid_disks
; i
++)
1321 if (r1_bio
->bios
[i
]->bi_end_io
== end_sync_read
) {
1323 int vcnt
= r1_bio
->sectors
>> (PAGE_SHIFT
- 9);
1324 struct bio
*pbio
= r1_bio
->bios
[primary
];
1325 struct bio
*sbio
= r1_bio
->bios
[i
];
1327 if (test_bit(BIO_UPTODATE
, &sbio
->bi_flags
)) {
1328 for (j
= vcnt
; j
-- ; ) {
1330 p
= pbio
->bi_io_vec
[j
].bv_page
;
1331 s
= sbio
->bi_io_vec
[j
].bv_page
;
1332 if (memcmp(page_address(p
),
1340 mddev
->resync_mismatches
+= r1_bio
->sectors
;
1341 if (j
< 0 || (test_bit(MD_RECOVERY_CHECK
, &mddev
->recovery
)
1342 && test_bit(BIO_UPTODATE
, &sbio
->bi_flags
))) {
1343 sbio
->bi_end_io
= NULL
;
1344 rdev_dec_pending(conf
->mirrors
[i
].rdev
, mddev
);
1346 /* fixup the bio for reuse */
1348 sbio
->bi_vcnt
= vcnt
;
1349 sbio
->bi_size
= r1_bio
->sectors
<< 9;
1351 sbio
->bi_phys_segments
= 0;
1352 sbio
->bi_flags
&= ~(BIO_POOL_MASK
- 1);
1353 sbio
->bi_flags
|= 1 << BIO_UPTODATE
;
1354 sbio
->bi_next
= NULL
;
1355 sbio
->bi_sector
= r1_bio
->sector
+
1356 conf
->mirrors
[i
].rdev
->data_offset
;
1357 sbio
->bi_bdev
= conf
->mirrors
[i
].rdev
->bdev
;
1358 size
= sbio
->bi_size
;
1359 for (j
= 0; j
< vcnt
; j
++) {
1361 bi
= &sbio
->bi_io_vec
[j
];
1363 if (size
> PAGE_SIZE
)
1364 bi
->bv_len
= PAGE_SIZE
;
1368 memcpy(page_address(bi
->bv_page
),
1369 page_address(pbio
->bi_io_vec
[j
].bv_page
),
1376 if (!test_bit(R1BIO_Uptodate
, &r1_bio
->state
)) {
1377 /* ouch - failed to read all of that.
1378 * Try some synchronous reads of other devices to get
1379 * good data, much like with normal read errors. Only
1380 * read into the pages we already have so we don't
1381 * need to re-issue the read request.
1382 * We don't need to freeze the array, because being in an
1383 * active sync request, there is no normal IO, and
1384 * no overlapping syncs.
1386 sector_t sect
= r1_bio
->sector
;
1387 int sectors
= r1_bio
->sectors
;
1392 int d
= r1_bio
->read_disk
;
1396 if (s
> (PAGE_SIZE
>>9))
1399 if (r1_bio
->bios
[d
]->bi_end_io
== end_sync_read
) {
1400 /* No rcu protection needed here devices
1401 * can only be removed when no resync is
1402 * active, and resync is currently active
1404 rdev
= conf
->mirrors
[d
].rdev
;
1405 if (sync_page_io(rdev
->bdev
,
1406 sect
+ rdev
->data_offset
,
1408 bio
->bi_io_vec
[idx
].bv_page
,
1415 if (d
== conf
->raid_disks
)
1417 } while (!success
&& d
!= r1_bio
->read_disk
);
1421 /* write it back and re-read */
1422 set_bit(R1BIO_Uptodate
, &r1_bio
->state
);
1423 while (d
!= r1_bio
->read_disk
) {
1425 d
= conf
->raid_disks
;
1427 if (r1_bio
->bios
[d
]->bi_end_io
!= end_sync_read
)
1429 rdev
= conf
->mirrors
[d
].rdev
;
1430 atomic_add(s
, &rdev
->corrected_errors
);
1431 if (sync_page_io(rdev
->bdev
,
1432 sect
+ rdev
->data_offset
,
1434 bio
->bi_io_vec
[idx
].bv_page
,
1436 md_error(mddev
, rdev
);
1439 while (d
!= r1_bio
->read_disk
) {
1441 d
= conf
->raid_disks
;
1443 if (r1_bio
->bios
[d
]->bi_end_io
!= end_sync_read
)
1445 rdev
= conf
->mirrors
[d
].rdev
;
1446 if (sync_page_io(rdev
->bdev
,
1447 sect
+ rdev
->data_offset
,
1449 bio
->bi_io_vec
[idx
].bv_page
,
1451 md_error(mddev
, rdev
);
1454 char b
[BDEVNAME_SIZE
];
1455 /* Cannot read from anywhere, array is toast */
1456 md_error(mddev
, conf
->mirrors
[r1_bio
->read_disk
].rdev
);
1457 printk(KERN_ALERT
"raid1: %s: unrecoverable I/O read error"
1458 " 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 "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 BIO_RW_BARRIER
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 bool do_sync
= bio_rw_flagged(r1_bio
->master_bio
, BIO_RW_SYNCIO
);
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
|
1658 (do_sync
<< BIO_RW_SYNCIO
);
1659 bio
->bi_private
= r1_bio
;
1660 r1_bio
->bios
[i
] = bio
;
1661 generic_make_request(bio
);
1666 /* we got a read error. Maybe the drive is bad. Maybe just
1667 * the block and we can fix it.
1668 * We freeze all other IO, and try reading the block from
1669 * other devices. When we find one, we re-write
1670 * and check it that fixes the read error.
1671 * This is all done synchronously while the array is
1674 if (mddev
->ro
== 0) {
1676 fix_read_error(conf
, r1_bio
->read_disk
,
1679 unfreeze_array(conf
);
1682 conf
->mirrors
[r1_bio
->read_disk
].rdev
);
1684 bio
= r1_bio
->bios
[r1_bio
->read_disk
];
1685 if ((disk
=read_balance(conf
, r1_bio
)) == -1) {
1686 printk(KERN_ALERT
"raid1: %s: unrecoverable I/O"
1687 " 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 bool do_sync
= bio_rw_flagged(r1_bio
->master_bio
, BIO_RW_SYNCIO
);
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
"raid1: %s: redirecting sector %llu to"
1702 " another mirror\n",
1703 bdevname(rdev
->bdev
,b
),
1704 (unsigned long long)r1_bio
->sector
);
1705 bio
->bi_sector
= r1_bio
->sector
+ rdev
->data_offset
;
1706 bio
->bi_bdev
= rdev
->bdev
;
1707 bio
->bi_end_io
= raid1_end_read_request
;
1708 bio
->bi_rw
= READ
| (do_sync
<< BIO_RW_SYNCIO
);
1709 bio
->bi_private
= r1_bio
;
1711 generic_make_request(bio
);
1717 unplug_slaves(mddev
);
1721 static int init_resync(conf_t
*conf
)
1725 buffs
= RESYNC_WINDOW
/ RESYNC_BLOCK_SIZE
;
1726 BUG_ON(conf
->r1buf_pool
);
1727 conf
->r1buf_pool
= mempool_create(buffs
, r1buf_pool_alloc
, r1buf_pool_free
,
1729 if (!conf
->r1buf_pool
)
1731 conf
->next_resync
= 0;
1736 * perform a "sync" on one "block"
1738 * We need to make sure that no normal I/O request - particularly write
1739 * requests - conflict with active sync requests.
1741 * This is achieved by tracking pending requests and a 'barrier' concept
1742 * that can be installed to exclude normal IO requests.
1745 static sector_t
sync_request(mddev_t
*mddev
, sector_t sector_nr
, int *skipped
, int go_faster
)
1747 conf_t
*conf
= mddev
->private;
1750 sector_t max_sector
, nr_sectors
;
1754 int write_targets
= 0, read_targets
= 0;
1756 int still_degraded
= 0;
1758 if (!conf
->r1buf_pool
)
1761 printk("sync start - bitmap %p\n", mddev->bitmap);
1763 if (init_resync(conf
))
1767 max_sector
= mddev
->dev_sectors
;
1768 if (sector_nr
>= max_sector
) {
1769 /* If we aborted, we need to abort the
1770 * sync on the 'current' bitmap chunk (there will
1771 * only be one in raid1 resync.
1772 * We can find the current addess in mddev->curr_resync
1774 if (mddev
->curr_resync
< max_sector
) /* aborted */
1775 bitmap_end_sync(mddev
->bitmap
, mddev
->curr_resync
,
1777 else /* completed sync */
1780 bitmap_close_sync(mddev
->bitmap
);
1785 if (mddev
->bitmap
== NULL
&&
1786 mddev
->recovery_cp
== MaxSector
&&
1787 !test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
) &&
1788 conf
->fullsync
== 0) {
1790 return max_sector
- sector_nr
;
1792 /* before building a request, check if we can skip these blocks..
1793 * This call the bitmap_start_sync doesn't actually record anything
1795 if (!bitmap_start_sync(mddev
->bitmap
, sector_nr
, &sync_blocks
, 1) &&
1796 !conf
->fullsync
&& !test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
)) {
1797 /* We can skip this block, and probably several more */
1802 * If there is non-resync activity waiting for a turn,
1803 * and resync is going fast enough,
1804 * then let it though before starting on this new sync request.
1806 if (!go_faster
&& conf
->nr_waiting
)
1807 msleep_interruptible(1000);
1809 bitmap_cond_end_sync(mddev
->bitmap
, sector_nr
);
1810 raise_barrier(conf
);
1812 conf
->next_resync
= sector_nr
;
1814 r1_bio
= mempool_alloc(conf
->r1buf_pool
, GFP_NOIO
);
1817 * If we get a correctably read error during resync or recovery,
1818 * we might want to read from a different device. So we
1819 * flag all drives that could conceivably be read from for READ,
1820 * and any others (which will be non-In_sync devices) for WRITE.
1821 * If a read fails, we try reading from something else for which READ
1825 r1_bio
->mddev
= mddev
;
1826 r1_bio
->sector
= sector_nr
;
1828 set_bit(R1BIO_IsSync
, &r1_bio
->state
);
1830 for (i
=0; i
< conf
->raid_disks
; i
++) {
1832 bio
= r1_bio
->bios
[i
];
1834 /* take from bio_init */
1835 bio
->bi_next
= NULL
;
1836 bio
->bi_flags
|= 1 << BIO_UPTODATE
;
1840 bio
->bi_phys_segments
= 0;
1842 bio
->bi_end_io
= NULL
;
1843 bio
->bi_private
= NULL
;
1845 rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
1847 test_bit(Faulty
, &rdev
->flags
)) {
1850 } else if (!test_bit(In_sync
, &rdev
->flags
)) {
1852 bio
->bi_end_io
= end_sync_write
;
1855 /* may need to read from here */
1857 bio
->bi_end_io
= end_sync_read
;
1858 if (test_bit(WriteMostly
, &rdev
->flags
)) {
1867 atomic_inc(&rdev
->nr_pending
);
1868 bio
->bi_sector
= sector_nr
+ rdev
->data_offset
;
1869 bio
->bi_bdev
= rdev
->bdev
;
1870 bio
->bi_private
= r1_bio
;
1875 r1_bio
->read_disk
= disk
;
1877 if (test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
) && read_targets
> 0)
1878 /* extra read targets are also write targets */
1879 write_targets
+= read_targets
-1;
1881 if (write_targets
== 0 || read_targets
== 0) {
1882 /* There is nowhere to write, so all non-sync
1883 * drives must be failed - so we are finished
1885 sector_t rv
= max_sector
- sector_nr
;
1891 if (max_sector
> mddev
->resync_max
)
1892 max_sector
= mddev
->resync_max
; /* Don't do IO beyond here */
1897 int len
= PAGE_SIZE
;
1898 if (sector_nr
+ (len
>>9) > max_sector
)
1899 len
= (max_sector
- sector_nr
) << 9;
1902 if (sync_blocks
== 0) {
1903 if (!bitmap_start_sync(mddev
->bitmap
, sector_nr
,
1904 &sync_blocks
, still_degraded
) &&
1906 !test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
))
1908 BUG_ON(sync_blocks
< (PAGE_SIZE
>>9));
1909 if (len
> (sync_blocks
<<9))
1910 len
= sync_blocks
<<9;
1913 for (i
=0 ; i
< conf
->raid_disks
; i
++) {
1914 bio
= r1_bio
->bios
[i
];
1915 if (bio
->bi_end_io
) {
1916 page
= bio
->bi_io_vec
[bio
->bi_vcnt
].bv_page
;
1917 if (bio_add_page(bio
, page
, len
, 0) == 0) {
1919 bio
->bi_io_vec
[bio
->bi_vcnt
].bv_page
= page
;
1922 bio
= r1_bio
->bios
[i
];
1923 if (bio
->bi_end_io
==NULL
)
1925 /* remove last page from this bio */
1927 bio
->bi_size
-= len
;
1928 bio
->bi_flags
&= ~(1<< BIO_SEG_VALID
);
1934 nr_sectors
+= len
>>9;
1935 sector_nr
+= len
>>9;
1936 sync_blocks
-= (len
>>9);
1937 } while (r1_bio
->bios
[disk
]->bi_vcnt
< RESYNC_PAGES
);
1939 r1_bio
->sectors
= nr_sectors
;
1941 /* For a user-requested sync, we read all readable devices and do a
1944 if (test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
)) {
1945 atomic_set(&r1_bio
->remaining
, read_targets
);
1946 for (i
=0; i
<conf
->raid_disks
; i
++) {
1947 bio
= r1_bio
->bios
[i
];
1948 if (bio
->bi_end_io
== end_sync_read
) {
1949 md_sync_acct(bio
->bi_bdev
, nr_sectors
);
1950 generic_make_request(bio
);
1954 atomic_set(&r1_bio
->remaining
, 1);
1955 bio
= r1_bio
->bios
[r1_bio
->read_disk
];
1956 md_sync_acct(bio
->bi_bdev
, nr_sectors
);
1957 generic_make_request(bio
);
1963 static sector_t
raid1_size(mddev_t
*mddev
, sector_t sectors
, int raid_disks
)
1968 return mddev
->dev_sectors
;
1971 static conf_t
*setup_conf(mddev_t
*mddev
)
1975 mirror_info_t
*disk
;
1979 conf
= kzalloc(sizeof(conf_t
), GFP_KERNEL
);
1983 conf
->mirrors
= kzalloc(sizeof(struct mirror_info
)*mddev
->raid_disks
,
1988 conf
->tmppage
= alloc_page(GFP_KERNEL
);
1992 conf
->poolinfo
= kzalloc(sizeof(*conf
->poolinfo
), GFP_KERNEL
);
1993 if (!conf
->poolinfo
)
1995 conf
->poolinfo
->raid_disks
= mddev
->raid_disks
;
1996 conf
->r1bio_pool
= mempool_create(NR_RAID1_BIOS
, r1bio_pool_alloc
,
1999 if (!conf
->r1bio_pool
)
2002 conf
->poolinfo
->mddev
= mddev
;
2004 spin_lock_init(&conf
->device_lock
);
2005 list_for_each_entry(rdev
, &mddev
->disks
, same_set
) {
2006 int disk_idx
= rdev
->raid_disk
;
2007 if (disk_idx
>= mddev
->raid_disks
2010 disk
= conf
->mirrors
+ disk_idx
;
2014 disk
->head_position
= 0;
2016 conf
->raid_disks
= mddev
->raid_disks
;
2017 conf
->mddev
= mddev
;
2018 INIT_LIST_HEAD(&conf
->retry_list
);
2020 spin_lock_init(&conf
->resync_lock
);
2021 init_waitqueue_head(&conf
->wait_barrier
);
2023 bio_list_init(&conf
->pending_bio_list
);
2024 bio_list_init(&conf
->flushing_bio_list
);
2026 conf
->last_used
= -1;
2027 for (i
= 0; i
< conf
->raid_disks
; i
++) {
2029 disk
= conf
->mirrors
+ i
;
2032 !test_bit(In_sync
, &disk
->rdev
->flags
)) {
2033 disk
->head_position
= 0;
2036 } else if (conf
->last_used
< 0)
2038 * The first working device is used as a
2039 * starting point to read balancing.
2041 conf
->last_used
= i
;
2045 if (conf
->last_used
< 0) {
2046 printk(KERN_ERR
"raid1: no operational mirrors for %s\n",
2051 conf
->thread
= md_register_thread(raid1d
, mddev
, NULL
);
2052 if (!conf
->thread
) {
2054 "raid1: couldn't allocate thread for %s\n",
2063 if (conf
->r1bio_pool
)
2064 mempool_destroy(conf
->r1bio_pool
);
2065 kfree(conf
->mirrors
);
2066 safe_put_page(conf
->tmppage
);
2067 kfree(conf
->poolinfo
);
2070 return ERR_PTR(err
);
2073 static int run(mddev_t
*mddev
)
2079 if (mddev
->level
!= 1) {
2080 printk("raid1: %s: raid level not set to mirroring (%d)\n",
2081 mdname(mddev
), mddev
->level
);
2084 if (mddev
->reshape_position
!= MaxSector
) {
2085 printk("raid1: %s: reshape_position set but not supported\n",
2090 * copy the already verified devices into our private RAID1
2091 * bookkeeping area. [whatever we allocate in run(),
2092 * should be freed in stop()]
2094 if (mddev
->private == NULL
)
2095 conf
= setup_conf(mddev
);
2097 conf
= mddev
->private;
2100 return PTR_ERR(conf
);
2102 mddev
->queue
->queue_lock
= &conf
->device_lock
;
2103 list_for_each_entry(rdev
, &mddev
->disks
, same_set
) {
2104 disk_stack_limits(mddev
->gendisk
, rdev
->bdev
,
2105 rdev
->data_offset
<< 9);
2106 /* as we don't honour merge_bvec_fn, we must never risk
2107 * violating it, so limit ->max_segments to 1 lying within
2108 * a single page, as a one page request is never in violation.
2110 if (rdev
->bdev
->bd_disk
->queue
->merge_bvec_fn
) {
2111 blk_queue_max_segments(mddev
->queue
, 1);
2112 blk_queue_segment_boundary(mddev
->queue
,
2113 PAGE_CACHE_SIZE
- 1);
2117 mddev
->degraded
= 0;
2118 for (i
=0; i
< conf
->raid_disks
; i
++)
2119 if (conf
->mirrors
[i
].rdev
== NULL
||
2120 !test_bit(In_sync
, &conf
->mirrors
[i
].rdev
->flags
) ||
2121 test_bit(Faulty
, &conf
->mirrors
[i
].rdev
->flags
))
2124 if (conf
->raid_disks
- mddev
->degraded
== 1)
2125 mddev
->recovery_cp
= MaxSector
;
2127 if (mddev
->recovery_cp
!= MaxSector
)
2128 printk(KERN_NOTICE
"raid1: %s is not clean"
2129 " -- starting background reconstruction\n",
2132 "raid1: raid set %s active with %d out of %d mirrors\n",
2133 mdname(mddev
), mddev
->raid_disks
- mddev
->degraded
,
2137 * Ok, everything is just fine now
2139 mddev
->thread
= conf
->thread
;
2140 conf
->thread
= NULL
;
2141 mddev
->private = conf
;
2143 md_set_array_sectors(mddev
, raid1_size(mddev
, 0, 0));
2145 mddev
->queue
->unplug_fn
= raid1_unplug
;
2146 mddev
->queue
->backing_dev_info
.congested_fn
= raid1_congested
;
2147 mddev
->queue
->backing_dev_info
.congested_data
= mddev
;
2148 md_integrity_register(mddev
);
2152 static int stop(mddev_t
*mddev
)
2154 conf_t
*conf
= mddev
->private;
2155 struct bitmap
*bitmap
= mddev
->bitmap
;
2156 int behind_wait
= 0;
2158 /* wait for behind writes to complete */
2159 while (bitmap
&& atomic_read(&bitmap
->behind_writes
) > 0) {
2161 printk(KERN_INFO
"raid1: behind writes in progress on device %s, waiting to stop (%d)\n", mdname(mddev
), behind_wait
);
2162 set_current_state(TASK_UNINTERRUPTIBLE
);
2163 schedule_timeout(HZ
); /* wait a second */
2164 /* need to kick something here to make sure I/O goes? */
2167 raise_barrier(conf
);
2168 lower_barrier(conf
);
2170 md_unregister_thread(mddev
->thread
);
2171 mddev
->thread
= NULL
;
2172 blk_sync_queue(mddev
->queue
); /* the unplug fn references 'conf'*/
2173 if (conf
->r1bio_pool
)
2174 mempool_destroy(conf
->r1bio_pool
);
2175 kfree(conf
->mirrors
);
2176 kfree(conf
->poolinfo
);
2178 mddev
->private = NULL
;
2182 static int raid1_resize(mddev_t
*mddev
, sector_t sectors
)
2184 /* no resync is happening, and there is enough space
2185 * on all devices, so we can resize.
2186 * We need to make sure resync covers any new space.
2187 * If the array is shrinking we should possibly wait until
2188 * any io in the removed space completes, but it hardly seems
2191 md_set_array_sectors(mddev
, raid1_size(mddev
, sectors
, 0));
2192 if (mddev
->array_sectors
> raid1_size(mddev
, sectors
, 0))
2194 set_capacity(mddev
->gendisk
, mddev
->array_sectors
);
2196 revalidate_disk(mddev
->gendisk
);
2197 if (sectors
> mddev
->dev_sectors
&&
2198 mddev
->recovery_cp
== MaxSector
) {
2199 mddev
->recovery_cp
= mddev
->dev_sectors
;
2200 set_bit(MD_RECOVERY_NEEDED
, &mddev
->recovery
);
2202 mddev
->dev_sectors
= sectors
;
2203 mddev
->resync_max_sectors
= sectors
;
2207 static int raid1_reshape(mddev_t
*mddev
)
2210 * 1/ resize the r1bio_pool
2211 * 2/ resize conf->mirrors
2213 * We allocate a new r1bio_pool if we can.
2214 * Then raise a device barrier and wait until all IO stops.
2215 * Then resize conf->mirrors and swap in the new r1bio pool.
2217 * At the same time, we "pack" the devices so that all the missing
2218 * devices have the higher raid_disk numbers.
2220 mempool_t
*newpool
, *oldpool
;
2221 struct pool_info
*newpoolinfo
;
2222 mirror_info_t
*newmirrors
;
2223 conf_t
*conf
= mddev
->private;
2224 int cnt
, raid_disks
;
2225 unsigned long flags
;
2228 /* Cannot change chunk_size, layout, or level */
2229 if (mddev
->chunk_sectors
!= mddev
->new_chunk_sectors
||
2230 mddev
->layout
!= mddev
->new_layout
||
2231 mddev
->level
!= mddev
->new_level
) {
2232 mddev
->new_chunk_sectors
= mddev
->chunk_sectors
;
2233 mddev
->new_layout
= mddev
->layout
;
2234 mddev
->new_level
= mddev
->level
;
2238 err
= md_allow_write(mddev
);
2242 raid_disks
= mddev
->raid_disks
+ mddev
->delta_disks
;
2244 if (raid_disks
< conf
->raid_disks
) {
2246 for (d
= 0; d
< conf
->raid_disks
; d
++)
2247 if (conf
->mirrors
[d
].rdev
)
2249 if (cnt
> raid_disks
)
2253 newpoolinfo
= kmalloc(sizeof(*newpoolinfo
), GFP_KERNEL
);
2256 newpoolinfo
->mddev
= mddev
;
2257 newpoolinfo
->raid_disks
= raid_disks
;
2259 newpool
= mempool_create(NR_RAID1_BIOS
, r1bio_pool_alloc
,
2260 r1bio_pool_free
, newpoolinfo
);
2265 newmirrors
= kzalloc(sizeof(struct mirror_info
) * raid_disks
, GFP_KERNEL
);
2268 mempool_destroy(newpool
);
2272 raise_barrier(conf
);
2274 /* ok, everything is stopped */
2275 oldpool
= conf
->r1bio_pool
;
2276 conf
->r1bio_pool
= newpool
;
2278 for (d
= d2
= 0; d
< conf
->raid_disks
; d
++) {
2279 mdk_rdev_t
*rdev
= conf
->mirrors
[d
].rdev
;
2280 if (rdev
&& rdev
->raid_disk
!= d2
) {
2282 sprintf(nm
, "rd%d", rdev
->raid_disk
);
2283 sysfs_remove_link(&mddev
->kobj
, nm
);
2284 rdev
->raid_disk
= d2
;
2285 sprintf(nm
, "rd%d", rdev
->raid_disk
);
2286 sysfs_remove_link(&mddev
->kobj
, nm
);
2287 if (sysfs_create_link(&mddev
->kobj
,
2290 "md/raid1: cannot register "
2295 newmirrors
[d2
++].rdev
= rdev
;
2297 kfree(conf
->mirrors
);
2298 conf
->mirrors
= newmirrors
;
2299 kfree(conf
->poolinfo
);
2300 conf
->poolinfo
= newpoolinfo
;
2302 spin_lock_irqsave(&conf
->device_lock
, flags
);
2303 mddev
->degraded
+= (raid_disks
- conf
->raid_disks
);
2304 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
2305 conf
->raid_disks
= mddev
->raid_disks
= raid_disks
;
2306 mddev
->delta_disks
= 0;
2308 conf
->last_used
= 0; /* just make sure it is in-range */
2309 lower_barrier(conf
);
2311 set_bit(MD_RECOVERY_NEEDED
, &mddev
->recovery
);
2312 md_wakeup_thread(mddev
->thread
);
2314 mempool_destroy(oldpool
);
2318 static void raid1_quiesce(mddev_t
*mddev
, int state
)
2320 conf_t
*conf
= mddev
->private;
2323 case 2: /* wake for suspend */
2324 wake_up(&conf
->wait_barrier
);
2327 raise_barrier(conf
);
2330 lower_barrier(conf
);
2335 static void *raid1_takeover(mddev_t
*mddev
)
2337 /* raid1 can take over:
2338 * raid5 with 2 devices, any layout or chunk size
2340 if (mddev
->level
== 5 && mddev
->raid_disks
== 2) {
2342 mddev
->new_level
= 1;
2343 mddev
->new_layout
= 0;
2344 mddev
->new_chunk_sectors
= 0;
2345 conf
= setup_conf(mddev
);
2350 return ERR_PTR(-EINVAL
);
2353 static struct mdk_personality raid1_personality
=
2357 .owner
= THIS_MODULE
,
2358 .make_request
= make_request
,
2362 .error_handler
= error
,
2363 .hot_add_disk
= raid1_add_disk
,
2364 .hot_remove_disk
= raid1_remove_disk
,
2365 .spare_active
= raid1_spare_active
,
2366 .sync_request
= sync_request
,
2367 .resize
= raid1_resize
,
2369 .check_reshape
= raid1_reshape
,
2370 .quiesce
= raid1_quiesce
,
2371 .takeover
= raid1_takeover
,
2374 static int __init
raid_init(void)
2376 return register_md_personality(&raid1_personality
);
2379 static void raid_exit(void)
2381 unregister_md_personality(&raid1_personality
);
2384 module_init(raid_init
);
2385 module_exit(raid_exit
);
2386 MODULE_LICENSE("GPL");
2387 MODULE_DESCRIPTION("RAID1 (mirroring) personality for MD");
2388 MODULE_ALIAS("md-personality-3"); /* RAID1 */
2389 MODULE_ALIAS("md-raid1");
2390 MODULE_ALIAS("md-level-1");