2 * raid10.c : Multiple Devices driver for Linux
4 * Copyright (C) 2000-2004 Neil Brown
6 * RAID-10 support for md.
8 * Base on code in raid1.c. See raid1.c for further copyright information.
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2, or (at your option)
16 * You should have received a copy of the GNU General Public License
17 * (for example /usr/src/linux/COPYING); if not, write to the Free
18 * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21 #include <linux/slab.h>
22 #include <linux/delay.h>
23 #include <linux/blkdev.h>
24 #include <linux/module.h>
25 #include <linux/seq_file.h>
26 #include <linux/ratelimit.h>
27 #include <linux/kthread.h>
34 * RAID10 provides a combination of RAID0 and RAID1 functionality.
35 * The layout of data is defined by
38 * near_copies (stored in low byte of layout)
39 * far_copies (stored in second byte of layout)
40 * far_offset (stored in bit 16 of layout )
41 * use_far_sets (stored in bit 17 of layout )
43 * The data to be stored is divided into chunks using chunksize. Each device
44 * is divided into far_copies sections. In each section, chunks are laid out
45 * in a style similar to raid0, but near_copies copies of each chunk is stored
46 * (each on a different drive). The starting device for each section is offset
47 * near_copies from the starting device of the previous section. Thus there
48 * are (near_copies * far_copies) of each chunk, and each is on a different
49 * drive. near_copies and far_copies must be at least one, and their product
50 * is at most raid_disks.
52 * If far_offset is true, then the far_copies are handled a bit differently.
53 * The copies are still in different stripes, but instead of being very far
54 * apart on disk, there are adjacent stripes.
56 * The far and offset algorithms are handled slightly differently if
57 * 'use_far_sets' is true. In this case, the array's devices are grouped into
58 * sets that are (near_copies * far_copies) in size. The far copied stripes
59 * are still shifted by 'near_copies' devices, but this shifting stays confined
60 * to the set rather than the entire array. This is done to improve the number
61 * of device combinations that can fail without causing the array to fail.
62 * Example 'far' algorithm w/o 'use_far_sets' (each letter represents a chunk
67 * Example 'far' algorithm w/ 'use_far_sets' enabled (sets illustrated w/ []'s):
68 * [A B] [C D] [A B] [C D E]
69 * |...| |...| |...| | ... |
70 * [B A] [D C] [B A] [E C D]
74 * Number of guaranteed r10bios in case of extreme VM load:
76 #define NR_RAID10_BIOS 256
78 /* when we get a read error on a read-only array, we redirect to another
79 * device without failing the first device, or trying to over-write to
80 * correct the read error. To keep track of bad blocks on a per-bio
81 * level, we store IO_BLOCKED in the appropriate 'bios' pointer
83 #define IO_BLOCKED ((struct bio *)1)
84 /* When we successfully write to a known bad-block, we need to remove the
85 * bad-block marking which must be done from process context. So we record
86 * the success by setting devs[n].bio to IO_MADE_GOOD
88 #define IO_MADE_GOOD ((struct bio *)2)
90 #define BIO_SPECIAL(bio) ((unsigned long)bio <= 2)
92 /* When there are this many requests queued to be written by
93 * the raid10 thread, we become 'congested' to provide back-pressure
96 static int max_queued_requests
= 1024;
98 static void allow_barrier(struct r10conf
*conf
);
99 static void lower_barrier(struct r10conf
*conf
);
100 static int _enough(struct r10conf
*conf
, int previous
, int ignore
);
101 static sector_t
reshape_request(struct mddev
*mddev
, sector_t sector_nr
,
103 static void reshape_request_write(struct mddev
*mddev
, struct r10bio
*r10_bio
);
104 static void end_reshape_write(struct bio
*bio
, int error
);
105 static void end_reshape(struct r10conf
*conf
);
107 static void * r10bio_pool_alloc(gfp_t gfp_flags
, void *data
)
109 struct r10conf
*conf
= data
;
110 int size
= offsetof(struct r10bio
, devs
[conf
->copies
]);
112 /* allocate a r10bio with room for raid_disks entries in the
114 return kzalloc(size
, gfp_flags
);
117 static void r10bio_pool_free(void *r10_bio
, void *data
)
122 /* Maximum size of each resync request */
123 #define RESYNC_BLOCK_SIZE (64*1024)
124 #define RESYNC_PAGES ((RESYNC_BLOCK_SIZE + PAGE_SIZE-1) / PAGE_SIZE)
125 /* amount of memory to reserve for resync requests */
126 #define RESYNC_WINDOW (1024*1024)
127 /* maximum number of concurrent requests, memory permitting */
128 #define RESYNC_DEPTH (32*1024*1024/RESYNC_BLOCK_SIZE)
131 * When performing a resync, we need to read and compare, so
132 * we need as many pages are there are copies.
133 * When performing a recovery, we need 2 bios, one for read,
134 * one for write (we recover only one drive per r10buf)
137 static void * r10buf_pool_alloc(gfp_t gfp_flags
, void *data
)
139 struct r10conf
*conf
= data
;
141 struct r10bio
*r10_bio
;
146 r10_bio
= r10bio_pool_alloc(gfp_flags
, conf
);
150 if (test_bit(MD_RECOVERY_SYNC
, &conf
->mddev
->recovery
) ||
151 test_bit(MD_RECOVERY_RESHAPE
, &conf
->mddev
->recovery
))
152 nalloc
= conf
->copies
; /* resync */
154 nalloc
= 2; /* recovery */
159 for (j
= nalloc
; j
-- ; ) {
160 bio
= bio_kmalloc(gfp_flags
, RESYNC_PAGES
);
163 r10_bio
->devs
[j
].bio
= bio
;
164 if (!conf
->have_replacement
)
166 bio
= bio_kmalloc(gfp_flags
, RESYNC_PAGES
);
169 r10_bio
->devs
[j
].repl_bio
= bio
;
172 * Allocate RESYNC_PAGES data pages and attach them
175 for (j
= 0 ; j
< nalloc
; j
++) {
176 struct bio
*rbio
= r10_bio
->devs
[j
].repl_bio
;
177 bio
= r10_bio
->devs
[j
].bio
;
178 for (i
= 0; i
< RESYNC_PAGES
; i
++) {
179 if (j
> 0 && !test_bit(MD_RECOVERY_SYNC
,
180 &conf
->mddev
->recovery
)) {
181 /* we can share bv_page's during recovery
183 struct bio
*rbio
= r10_bio
->devs
[0].bio
;
184 page
= rbio
->bi_io_vec
[i
].bv_page
;
187 page
= alloc_page(gfp_flags
);
191 bio
->bi_io_vec
[i
].bv_page
= page
;
193 rbio
->bi_io_vec
[i
].bv_page
= page
;
201 safe_put_page(bio
->bi_io_vec
[i
-1].bv_page
);
203 for (i
= 0; i
< RESYNC_PAGES
; i
++)
204 safe_put_page(r10_bio
->devs
[j
].bio
->bi_io_vec
[i
].bv_page
);
207 for ( ; j
< nalloc
; j
++) {
208 if (r10_bio
->devs
[j
].bio
)
209 bio_put(r10_bio
->devs
[j
].bio
);
210 if (r10_bio
->devs
[j
].repl_bio
)
211 bio_put(r10_bio
->devs
[j
].repl_bio
);
213 r10bio_pool_free(r10_bio
, conf
);
217 static void r10buf_pool_free(void *__r10_bio
, void *data
)
220 struct r10conf
*conf
= data
;
221 struct r10bio
*r10bio
= __r10_bio
;
224 for (j
=0; j
< conf
->copies
; j
++) {
225 struct bio
*bio
= r10bio
->devs
[j
].bio
;
227 for (i
= 0; i
< RESYNC_PAGES
; i
++) {
228 safe_put_page(bio
->bi_io_vec
[i
].bv_page
);
229 bio
->bi_io_vec
[i
].bv_page
= NULL
;
233 bio
= r10bio
->devs
[j
].repl_bio
;
237 r10bio_pool_free(r10bio
, conf
);
240 static void put_all_bios(struct r10conf
*conf
, struct r10bio
*r10_bio
)
244 for (i
= 0; i
< conf
->copies
; i
++) {
245 struct bio
**bio
= & r10_bio
->devs
[i
].bio
;
246 if (!BIO_SPECIAL(*bio
))
249 bio
= &r10_bio
->devs
[i
].repl_bio
;
250 if (r10_bio
->read_slot
< 0 && !BIO_SPECIAL(*bio
))
256 static void free_r10bio(struct r10bio
*r10_bio
)
258 struct r10conf
*conf
= r10_bio
->mddev
->private;
260 put_all_bios(conf
, r10_bio
);
261 mempool_free(r10_bio
, conf
->r10bio_pool
);
264 static void put_buf(struct r10bio
*r10_bio
)
266 struct r10conf
*conf
= r10_bio
->mddev
->private;
268 mempool_free(r10_bio
, conf
->r10buf_pool
);
273 static void reschedule_retry(struct r10bio
*r10_bio
)
276 struct mddev
*mddev
= r10_bio
->mddev
;
277 struct r10conf
*conf
= mddev
->private;
279 spin_lock_irqsave(&conf
->device_lock
, flags
);
280 list_add(&r10_bio
->retry_list
, &conf
->retry_list
);
282 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
284 /* wake up frozen array... */
285 wake_up(&conf
->wait_barrier
);
287 md_wakeup_thread(mddev
->thread
);
291 * raid_end_bio_io() is called when we have finished servicing a mirrored
292 * operation and are ready to return a success/failure code to the buffer
295 static void raid_end_bio_io(struct r10bio
*r10_bio
)
297 struct bio
*bio
= r10_bio
->master_bio
;
299 struct r10conf
*conf
= r10_bio
->mddev
->private;
301 if (bio
->bi_phys_segments
) {
303 spin_lock_irqsave(&conf
->device_lock
, flags
);
304 bio
->bi_phys_segments
--;
305 done
= (bio
->bi_phys_segments
== 0);
306 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
309 if (!test_bit(R10BIO_Uptodate
, &r10_bio
->state
))
310 clear_bit(BIO_UPTODATE
, &bio
->bi_flags
);
314 * Wake up any possible resync thread that waits for the device
319 free_r10bio(r10_bio
);
323 * Update disk head position estimator based on IRQ completion info.
325 static inline void update_head_pos(int slot
, struct r10bio
*r10_bio
)
327 struct r10conf
*conf
= r10_bio
->mddev
->private;
329 conf
->mirrors
[r10_bio
->devs
[slot
].devnum
].head_position
=
330 r10_bio
->devs
[slot
].addr
+ (r10_bio
->sectors
);
334 * Find the disk number which triggered given bio
336 static int find_bio_disk(struct r10conf
*conf
, struct r10bio
*r10_bio
,
337 struct bio
*bio
, int *slotp
, int *replp
)
342 for (slot
= 0; slot
< conf
->copies
; slot
++) {
343 if (r10_bio
->devs
[slot
].bio
== bio
)
345 if (r10_bio
->devs
[slot
].repl_bio
== bio
) {
351 BUG_ON(slot
== conf
->copies
);
352 update_head_pos(slot
, r10_bio
);
358 return r10_bio
->devs
[slot
].devnum
;
361 static void raid10_end_read_request(struct bio
*bio
, int error
)
363 int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
364 struct r10bio
*r10_bio
= bio
->bi_private
;
366 struct md_rdev
*rdev
;
367 struct r10conf
*conf
= r10_bio
->mddev
->private;
369 slot
= r10_bio
->read_slot
;
370 dev
= r10_bio
->devs
[slot
].devnum
;
371 rdev
= r10_bio
->devs
[slot
].rdev
;
373 * this branch is our 'one mirror IO has finished' event handler:
375 update_head_pos(slot
, r10_bio
);
379 * Set R10BIO_Uptodate in our master bio, so that
380 * we will return a good error code to the higher
381 * levels even if IO on some other mirrored buffer fails.
383 * The 'master' represents the composite IO operation to
384 * user-side. So if something waits for IO, then it will
385 * wait for the 'master' bio.
387 set_bit(R10BIO_Uptodate
, &r10_bio
->state
);
389 /* If all other devices that store this block have
390 * failed, we want to return the error upwards rather
391 * than fail the last device. Here we redefine
392 * "uptodate" to mean "Don't want to retry"
394 if (!_enough(conf
, test_bit(R10BIO_Previous
, &r10_bio
->state
),
399 raid_end_bio_io(r10_bio
);
400 rdev_dec_pending(rdev
, conf
->mddev
);
403 * oops, read error - keep the refcount on the rdev
405 char b
[BDEVNAME_SIZE
];
406 printk_ratelimited(KERN_ERR
407 "md/raid10:%s: %s: rescheduling sector %llu\n",
409 bdevname(rdev
->bdev
, b
),
410 (unsigned long long)r10_bio
->sector
);
411 set_bit(R10BIO_ReadError
, &r10_bio
->state
);
412 reschedule_retry(r10_bio
);
416 static void close_write(struct r10bio
*r10_bio
)
418 /* clear the bitmap if all writes complete successfully */
419 bitmap_endwrite(r10_bio
->mddev
->bitmap
, r10_bio
->sector
,
421 !test_bit(R10BIO_Degraded
, &r10_bio
->state
),
423 md_write_end(r10_bio
->mddev
);
426 static void one_write_done(struct r10bio
*r10_bio
)
428 if (atomic_dec_and_test(&r10_bio
->remaining
)) {
429 if (test_bit(R10BIO_WriteError
, &r10_bio
->state
))
430 reschedule_retry(r10_bio
);
432 close_write(r10_bio
);
433 if (test_bit(R10BIO_MadeGood
, &r10_bio
->state
))
434 reschedule_retry(r10_bio
);
436 raid_end_bio_io(r10_bio
);
441 static void raid10_end_write_request(struct bio
*bio
, int error
)
443 int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
444 struct r10bio
*r10_bio
= bio
->bi_private
;
447 struct r10conf
*conf
= r10_bio
->mddev
->private;
449 struct md_rdev
*rdev
= NULL
;
451 dev
= find_bio_disk(conf
, r10_bio
, bio
, &slot
, &repl
);
454 rdev
= conf
->mirrors
[dev
].replacement
;
458 rdev
= conf
->mirrors
[dev
].rdev
;
461 * this branch is our 'one mirror IO has finished' event handler:
465 /* Never record new bad blocks to replacement,
468 md_error(rdev
->mddev
, rdev
);
470 set_bit(WriteErrorSeen
, &rdev
->flags
);
471 if (!test_and_set_bit(WantReplacement
, &rdev
->flags
))
472 set_bit(MD_RECOVERY_NEEDED
,
473 &rdev
->mddev
->recovery
);
474 set_bit(R10BIO_WriteError
, &r10_bio
->state
);
479 * Set R10BIO_Uptodate in our master bio, so that
480 * we will return a good error code for to the higher
481 * levels even if IO on some other mirrored buffer fails.
483 * The 'master' represents the composite IO operation to
484 * user-side. So if something waits for IO, then it will
485 * wait for the 'master' bio.
491 * Do not set R10BIO_Uptodate if the current device is
492 * rebuilding or Faulty. This is because we cannot use
493 * such device for properly reading the data back (we could
494 * potentially use it, if the current write would have felt
495 * before rdev->recovery_offset, but for simplicity we don't
498 if (test_bit(In_sync
, &rdev
->flags
) &&
499 !test_bit(Faulty
, &rdev
->flags
))
500 set_bit(R10BIO_Uptodate
, &r10_bio
->state
);
502 /* Maybe we can clear some bad blocks. */
503 if (is_badblock(rdev
,
504 r10_bio
->devs
[slot
].addr
,
506 &first_bad
, &bad_sectors
)) {
509 r10_bio
->devs
[slot
].repl_bio
= IO_MADE_GOOD
;
511 r10_bio
->devs
[slot
].bio
= IO_MADE_GOOD
;
513 set_bit(R10BIO_MadeGood
, &r10_bio
->state
);
519 * Let's see if all mirrored write operations have finished
522 one_write_done(r10_bio
);
524 rdev_dec_pending(rdev
, conf
->mddev
);
528 * RAID10 layout manager
529 * As well as the chunksize and raid_disks count, there are two
530 * parameters: near_copies and far_copies.
531 * near_copies * far_copies must be <= raid_disks.
532 * Normally one of these will be 1.
533 * If both are 1, we get raid0.
534 * If near_copies == raid_disks, we get raid1.
536 * Chunks are laid out in raid0 style with near_copies copies of the
537 * first chunk, followed by near_copies copies of the next chunk and
539 * If far_copies > 1, then after 1/far_copies of the array has been assigned
540 * as described above, we start again with a device offset of near_copies.
541 * So we effectively have another copy of the whole array further down all
542 * the drives, but with blocks on different drives.
543 * With this layout, and block is never stored twice on the one device.
545 * raid10_find_phys finds the sector offset of a given virtual sector
546 * on each device that it is on.
548 * raid10_find_virt does the reverse mapping, from a device and a
549 * sector offset to a virtual address
552 static void __raid10_find_phys(struct geom
*geo
, struct r10bio
*r10bio
)
560 int last_far_set_start
, last_far_set_size
;
562 last_far_set_start
= (geo
->raid_disks
/ geo
->far_set_size
) - 1;
563 last_far_set_start
*= geo
->far_set_size
;
565 last_far_set_size
= geo
->far_set_size
;
566 last_far_set_size
+= (geo
->raid_disks
% geo
->far_set_size
);
568 /* now calculate first sector/dev */
569 chunk
= r10bio
->sector
>> geo
->chunk_shift
;
570 sector
= r10bio
->sector
& geo
->chunk_mask
;
572 chunk
*= geo
->near_copies
;
574 dev
= sector_div(stripe
, geo
->raid_disks
);
576 stripe
*= geo
->far_copies
;
578 sector
+= stripe
<< geo
->chunk_shift
;
580 /* and calculate all the others */
581 for (n
= 0; n
< geo
->near_copies
; n
++) {
585 r10bio
->devs
[slot
].devnum
= d
;
586 r10bio
->devs
[slot
].addr
= s
;
589 for (f
= 1; f
< geo
->far_copies
; f
++) {
590 set
= d
/ geo
->far_set_size
;
591 d
+= geo
->near_copies
;
593 if ((geo
->raid_disks
% geo
->far_set_size
) &&
594 (d
> last_far_set_start
)) {
595 d
-= last_far_set_start
;
596 d
%= last_far_set_size
;
597 d
+= last_far_set_start
;
599 d
%= geo
->far_set_size
;
600 d
+= geo
->far_set_size
* set
;
603 r10bio
->devs
[slot
].devnum
= d
;
604 r10bio
->devs
[slot
].addr
= s
;
608 if (dev
>= geo
->raid_disks
) {
610 sector
+= (geo
->chunk_mask
+ 1);
615 static void raid10_find_phys(struct r10conf
*conf
, struct r10bio
*r10bio
)
617 struct geom
*geo
= &conf
->geo
;
619 if (conf
->reshape_progress
!= MaxSector
&&
620 ((r10bio
->sector
>= conf
->reshape_progress
) !=
621 conf
->mddev
->reshape_backwards
)) {
622 set_bit(R10BIO_Previous
, &r10bio
->state
);
625 clear_bit(R10BIO_Previous
, &r10bio
->state
);
627 __raid10_find_phys(geo
, r10bio
);
630 static sector_t
raid10_find_virt(struct r10conf
*conf
, sector_t sector
, int dev
)
632 sector_t offset
, chunk
, vchunk
;
633 /* Never use conf->prev as this is only called during resync
634 * or recovery, so reshape isn't happening
636 struct geom
*geo
= &conf
->geo
;
637 int far_set_start
= (dev
/ geo
->far_set_size
) * geo
->far_set_size
;
638 int far_set_size
= geo
->far_set_size
;
639 int last_far_set_start
;
641 if (geo
->raid_disks
% geo
->far_set_size
) {
642 last_far_set_start
= (geo
->raid_disks
/ geo
->far_set_size
) - 1;
643 last_far_set_start
*= geo
->far_set_size
;
645 if (dev
>= last_far_set_start
) {
646 far_set_size
= geo
->far_set_size
;
647 far_set_size
+= (geo
->raid_disks
% geo
->far_set_size
);
648 far_set_start
= last_far_set_start
;
652 offset
= sector
& geo
->chunk_mask
;
653 if (geo
->far_offset
) {
655 chunk
= sector
>> geo
->chunk_shift
;
656 fc
= sector_div(chunk
, geo
->far_copies
);
657 dev
-= fc
* geo
->near_copies
;
658 if (dev
< far_set_start
)
661 while (sector
>= geo
->stride
) {
662 sector
-= geo
->stride
;
663 if (dev
< (geo
->near_copies
+ far_set_start
))
664 dev
+= far_set_size
- geo
->near_copies
;
666 dev
-= geo
->near_copies
;
668 chunk
= sector
>> geo
->chunk_shift
;
670 vchunk
= chunk
* geo
->raid_disks
+ dev
;
671 sector_div(vchunk
, geo
->near_copies
);
672 return (vchunk
<< geo
->chunk_shift
) + offset
;
676 * raid10_mergeable_bvec -- tell bio layer if a two requests can be merged
677 * @mddev: the md device
678 * @bvm: properties of new bio
679 * @biovec: the request that could be merged to it.
681 * Return amount of bytes we can accept at this offset
682 * This requires checking for end-of-chunk if near_copies != raid_disks,
683 * and for subordinate merge_bvec_fns if merge_check_needed.
685 static int raid10_mergeable_bvec(struct mddev
*mddev
,
686 struct bvec_merge_data
*bvm
,
687 struct bio_vec
*biovec
)
689 struct r10conf
*conf
= mddev
->private;
690 sector_t sector
= bvm
->bi_sector
+ get_start_sect(bvm
->bi_bdev
);
692 unsigned int chunk_sectors
;
693 unsigned int bio_sectors
= bvm
->bi_size
>> 9;
694 struct geom
*geo
= &conf
->geo
;
696 chunk_sectors
= (conf
->geo
.chunk_mask
& conf
->prev
.chunk_mask
) + 1;
697 if (conf
->reshape_progress
!= MaxSector
&&
698 ((sector
>= conf
->reshape_progress
) !=
699 conf
->mddev
->reshape_backwards
))
702 if (geo
->near_copies
< geo
->raid_disks
) {
703 max
= (chunk_sectors
- ((sector
& (chunk_sectors
- 1))
704 + bio_sectors
)) << 9;
706 /* bio_add cannot handle a negative return */
708 if (max
<= biovec
->bv_len
&& bio_sectors
== 0)
709 return biovec
->bv_len
;
711 max
= biovec
->bv_len
;
713 if (mddev
->merge_check_needed
) {
715 struct r10bio r10_bio
;
716 struct r10dev devs
[conf
->copies
];
718 struct r10bio
*r10_bio
= &on_stack
.r10_bio
;
720 if (conf
->reshape_progress
!= MaxSector
) {
721 /* Cannot give any guidance during reshape */
722 if (max
<= biovec
->bv_len
&& bio_sectors
== 0)
723 return biovec
->bv_len
;
726 r10_bio
->sector
= sector
;
727 raid10_find_phys(conf
, r10_bio
);
729 for (s
= 0; s
< conf
->copies
; s
++) {
730 int disk
= r10_bio
->devs
[s
].devnum
;
731 struct md_rdev
*rdev
= rcu_dereference(
732 conf
->mirrors
[disk
].rdev
);
733 if (rdev
&& !test_bit(Faulty
, &rdev
->flags
)) {
734 struct request_queue
*q
=
735 bdev_get_queue(rdev
->bdev
);
736 if (q
->merge_bvec_fn
) {
737 bvm
->bi_sector
= r10_bio
->devs
[s
].addr
739 bvm
->bi_bdev
= rdev
->bdev
;
740 max
= min(max
, q
->merge_bvec_fn(
744 rdev
= rcu_dereference(conf
->mirrors
[disk
].replacement
);
745 if (rdev
&& !test_bit(Faulty
, &rdev
->flags
)) {
746 struct request_queue
*q
=
747 bdev_get_queue(rdev
->bdev
);
748 if (q
->merge_bvec_fn
) {
749 bvm
->bi_sector
= r10_bio
->devs
[s
].addr
751 bvm
->bi_bdev
= rdev
->bdev
;
752 max
= min(max
, q
->merge_bvec_fn(
763 * This routine returns the disk from which the requested read should
764 * be done. There is a per-array 'next expected sequential IO' sector
765 * number - if this matches on the next IO then we use the last disk.
766 * There is also a per-disk 'last know head position' sector that is
767 * maintained from IRQ contexts, both the normal and the resync IO
768 * completion handlers update this position correctly. If there is no
769 * perfect sequential match then we pick the disk whose head is closest.
771 * If there are 2 mirrors in the same 2 devices, performance degrades
772 * because position is mirror, not device based.
774 * The rdev for the device selected will have nr_pending incremented.
778 * FIXME: possibly should rethink readbalancing and do it differently
779 * depending on near_copies / far_copies geometry.
781 static struct md_rdev
*read_balance(struct r10conf
*conf
,
782 struct r10bio
*r10_bio
,
785 const sector_t this_sector
= r10_bio
->sector
;
787 int sectors
= r10_bio
->sectors
;
788 int best_good_sectors
;
789 sector_t new_distance
, best_dist
;
790 struct md_rdev
*best_rdev
, *rdev
= NULL
;
793 struct geom
*geo
= &conf
->geo
;
795 raid10_find_phys(conf
, r10_bio
);
798 sectors
= r10_bio
->sectors
;
801 best_dist
= MaxSector
;
802 best_good_sectors
= 0;
805 * Check if we can balance. We can balance on the whole
806 * device if no resync is going on (recovery is ok), or below
807 * the resync window. We take the first readable disk when
808 * above the resync window.
810 if (conf
->mddev
->recovery_cp
< MaxSector
811 && (this_sector
+ sectors
>= conf
->next_resync
))
814 for (slot
= 0; slot
< conf
->copies
; slot
++) {
819 if (r10_bio
->devs
[slot
].bio
== IO_BLOCKED
)
821 disk
= r10_bio
->devs
[slot
].devnum
;
822 rdev
= rcu_dereference(conf
->mirrors
[disk
].replacement
);
823 if (rdev
== NULL
|| test_bit(Faulty
, &rdev
->flags
) ||
824 test_bit(Unmerged
, &rdev
->flags
) ||
825 r10_bio
->devs
[slot
].addr
+ sectors
> rdev
->recovery_offset
)
826 rdev
= rcu_dereference(conf
->mirrors
[disk
].rdev
);
828 test_bit(Faulty
, &rdev
->flags
) ||
829 test_bit(Unmerged
, &rdev
->flags
))
831 if (!test_bit(In_sync
, &rdev
->flags
) &&
832 r10_bio
->devs
[slot
].addr
+ sectors
> rdev
->recovery_offset
)
835 dev_sector
= r10_bio
->devs
[slot
].addr
;
836 if (is_badblock(rdev
, dev_sector
, sectors
,
837 &first_bad
, &bad_sectors
)) {
838 if (best_dist
< MaxSector
)
839 /* Already have a better slot */
841 if (first_bad
<= dev_sector
) {
842 /* Cannot read here. If this is the
843 * 'primary' device, then we must not read
844 * beyond 'bad_sectors' from another device.
846 bad_sectors
-= (dev_sector
- first_bad
);
847 if (!do_balance
&& sectors
> bad_sectors
)
848 sectors
= bad_sectors
;
849 if (best_good_sectors
> sectors
)
850 best_good_sectors
= sectors
;
852 sector_t good_sectors
=
853 first_bad
- dev_sector
;
854 if (good_sectors
> best_good_sectors
) {
855 best_good_sectors
= good_sectors
;
860 /* Must read from here */
865 best_good_sectors
= sectors
;
870 /* This optimisation is debatable, and completely destroys
871 * sequential read speed for 'far copies' arrays. So only
872 * keep it for 'near' arrays, and review those later.
874 if (geo
->near_copies
> 1 && !atomic_read(&rdev
->nr_pending
))
877 /* for far > 1 always use the lowest address */
878 if (geo
->far_copies
> 1)
879 new_distance
= r10_bio
->devs
[slot
].addr
;
881 new_distance
= abs(r10_bio
->devs
[slot
].addr
-
882 conf
->mirrors
[disk
].head_position
);
883 if (new_distance
< best_dist
) {
884 best_dist
= new_distance
;
889 if (slot
>= conf
->copies
) {
895 atomic_inc(&rdev
->nr_pending
);
896 if (test_bit(Faulty
, &rdev
->flags
)) {
897 /* Cannot risk returning a device that failed
898 * before we inc'ed nr_pending
900 rdev_dec_pending(rdev
, conf
->mddev
);
903 r10_bio
->read_slot
= slot
;
907 *max_sectors
= best_good_sectors
;
912 static int raid10_congested(struct mddev
*mddev
, int bits
)
914 struct r10conf
*conf
= mddev
->private;
917 if ((bits
& (1 << WB_async_congested
)) &&
918 conf
->pending_count
>= max_queued_requests
)
923 (i
< conf
->geo
.raid_disks
|| i
< conf
->prev
.raid_disks
)
926 struct md_rdev
*rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
927 if (rdev
&& !test_bit(Faulty
, &rdev
->flags
)) {
928 struct request_queue
*q
= bdev_get_queue(rdev
->bdev
);
930 ret
|= bdi_congested(&q
->backing_dev_info
, bits
);
937 static void flush_pending_writes(struct r10conf
*conf
)
939 /* Any writes that have been queued but are awaiting
940 * bitmap updates get flushed here.
942 spin_lock_irq(&conf
->device_lock
);
944 if (conf
->pending_bio_list
.head
) {
946 bio
= bio_list_get(&conf
->pending_bio_list
);
947 conf
->pending_count
= 0;
948 spin_unlock_irq(&conf
->device_lock
);
949 /* flush any pending bitmap writes to disk
950 * before proceeding w/ I/O */
951 bitmap_unplug(conf
->mddev
->bitmap
);
952 wake_up(&conf
->wait_barrier
);
954 while (bio
) { /* submit pending writes */
955 struct bio
*next
= bio
->bi_next
;
957 if (unlikely((bio
->bi_rw
& REQ_DISCARD
) &&
958 !blk_queue_discard(bdev_get_queue(bio
->bi_bdev
))))
962 generic_make_request(bio
);
966 spin_unlock_irq(&conf
->device_lock
);
970 * Sometimes we need to suspend IO while we do something else,
971 * either some resync/recovery, or reconfigure the array.
972 * To do this we raise a 'barrier'.
973 * The 'barrier' is a counter that can be raised multiple times
974 * to count how many activities are happening which preclude
976 * We can only raise the barrier if there is no pending IO.
977 * i.e. if nr_pending == 0.
978 * We choose only to raise the barrier if no-one is waiting for the
979 * barrier to go down. This means that as soon as an IO request
980 * is ready, no other operations which require a barrier will start
981 * until the IO request has had a chance.
983 * So: regular IO calls 'wait_barrier'. When that returns there
984 * is no backgroup IO happening, It must arrange to call
985 * allow_barrier when it has finished its IO.
986 * backgroup IO calls must call raise_barrier. Once that returns
987 * there is no normal IO happeing. It must arrange to call
988 * lower_barrier when the particular background IO completes.
991 static void raise_barrier(struct r10conf
*conf
, int force
)
993 BUG_ON(force
&& !conf
->barrier
);
994 spin_lock_irq(&conf
->resync_lock
);
996 /* Wait until no block IO is waiting (unless 'force') */
997 wait_event_lock_irq(conf
->wait_barrier
, force
|| !conf
->nr_waiting
,
1000 /* block any new IO from starting */
1003 /* Now wait for all pending IO to complete */
1004 wait_event_lock_irq(conf
->wait_barrier
,
1005 !conf
->nr_pending
&& conf
->barrier
< RESYNC_DEPTH
,
1008 spin_unlock_irq(&conf
->resync_lock
);
1011 static void lower_barrier(struct r10conf
*conf
)
1013 unsigned long flags
;
1014 spin_lock_irqsave(&conf
->resync_lock
, flags
);
1016 spin_unlock_irqrestore(&conf
->resync_lock
, flags
);
1017 wake_up(&conf
->wait_barrier
);
1020 static void wait_barrier(struct r10conf
*conf
)
1022 spin_lock_irq(&conf
->resync_lock
);
1023 if (conf
->barrier
) {
1025 /* Wait for the barrier to drop.
1026 * However if there are already pending
1027 * requests (preventing the barrier from
1028 * rising completely), and the
1029 * pre-process bio queue isn't empty,
1030 * then don't wait, as we need to empty
1031 * that queue to get the nr_pending
1034 wait_event_lock_irq(conf
->wait_barrier
,
1036 (conf
->nr_pending
&&
1037 current
->bio_list
&&
1038 !bio_list_empty(current
->bio_list
)),
1043 spin_unlock_irq(&conf
->resync_lock
);
1046 static void allow_barrier(struct r10conf
*conf
)
1048 unsigned long flags
;
1049 spin_lock_irqsave(&conf
->resync_lock
, flags
);
1051 spin_unlock_irqrestore(&conf
->resync_lock
, flags
);
1052 wake_up(&conf
->wait_barrier
);
1055 static void freeze_array(struct r10conf
*conf
, int extra
)
1057 /* stop syncio and normal IO and wait for everything to
1059 * We increment barrier and nr_waiting, and then
1060 * wait until nr_pending match nr_queued+extra
1061 * This is called in the context of one normal IO request
1062 * that has failed. Thus any sync request that might be pending
1063 * will be blocked by nr_pending, and we need to wait for
1064 * pending IO requests to complete or be queued for re-try.
1065 * Thus the number queued (nr_queued) plus this request (extra)
1066 * must match the number of pending IOs (nr_pending) before
1069 spin_lock_irq(&conf
->resync_lock
);
1072 wait_event_lock_irq_cmd(conf
->wait_barrier
,
1073 conf
->nr_pending
== conf
->nr_queued
+extra
,
1075 flush_pending_writes(conf
));
1077 spin_unlock_irq(&conf
->resync_lock
);
1080 static void unfreeze_array(struct r10conf
*conf
)
1082 /* reverse the effect of the freeze */
1083 spin_lock_irq(&conf
->resync_lock
);
1086 wake_up(&conf
->wait_barrier
);
1087 spin_unlock_irq(&conf
->resync_lock
);
1090 static sector_t
choose_data_offset(struct r10bio
*r10_bio
,
1091 struct md_rdev
*rdev
)
1093 if (!test_bit(MD_RECOVERY_RESHAPE
, &rdev
->mddev
->recovery
) ||
1094 test_bit(R10BIO_Previous
, &r10_bio
->state
))
1095 return rdev
->data_offset
;
1097 return rdev
->new_data_offset
;
1100 struct raid10_plug_cb
{
1101 struct blk_plug_cb cb
;
1102 struct bio_list pending
;
1106 static void raid10_unplug(struct blk_plug_cb
*cb
, bool from_schedule
)
1108 struct raid10_plug_cb
*plug
= container_of(cb
, struct raid10_plug_cb
,
1110 struct mddev
*mddev
= plug
->cb
.data
;
1111 struct r10conf
*conf
= mddev
->private;
1114 if (from_schedule
|| current
->bio_list
) {
1115 spin_lock_irq(&conf
->device_lock
);
1116 bio_list_merge(&conf
->pending_bio_list
, &plug
->pending
);
1117 conf
->pending_count
+= plug
->pending_cnt
;
1118 spin_unlock_irq(&conf
->device_lock
);
1119 wake_up(&conf
->wait_barrier
);
1120 md_wakeup_thread(mddev
->thread
);
1125 /* we aren't scheduling, so we can do the write-out directly. */
1126 bio
= bio_list_get(&plug
->pending
);
1127 bitmap_unplug(mddev
->bitmap
);
1128 wake_up(&conf
->wait_barrier
);
1130 while (bio
) { /* submit pending writes */
1131 struct bio
*next
= bio
->bi_next
;
1132 bio
->bi_next
= NULL
;
1133 if (unlikely((bio
->bi_rw
& REQ_DISCARD
) &&
1134 !blk_queue_discard(bdev_get_queue(bio
->bi_bdev
))))
1135 /* Just ignore it */
1138 generic_make_request(bio
);
1144 static void __make_request(struct mddev
*mddev
, struct bio
*bio
)
1146 struct r10conf
*conf
= mddev
->private;
1147 struct r10bio
*r10_bio
;
1148 struct bio
*read_bio
;
1150 const int rw
= bio_data_dir(bio
);
1151 const unsigned long do_sync
= (bio
->bi_rw
& REQ_SYNC
);
1152 const unsigned long do_fua
= (bio
->bi_rw
& REQ_FUA
);
1153 const unsigned long do_discard
= (bio
->bi_rw
1154 & (REQ_DISCARD
| REQ_SECURE
));
1155 const unsigned long do_same
= (bio
->bi_rw
& REQ_WRITE_SAME
);
1156 unsigned long flags
;
1157 struct md_rdev
*blocked_rdev
;
1158 struct blk_plug_cb
*cb
;
1159 struct raid10_plug_cb
*plug
= NULL
;
1160 int sectors_handled
;
1165 * Register the new request and wait if the reconstruction
1166 * thread has put up a bar for new requests.
1167 * Continue immediately if no resync is active currently.
1171 sectors
= bio_sectors(bio
);
1172 while (test_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
) &&
1173 bio
->bi_iter
.bi_sector
< conf
->reshape_progress
&&
1174 bio
->bi_iter
.bi_sector
+ sectors
> conf
->reshape_progress
) {
1175 /* IO spans the reshape position. Need to wait for
1178 allow_barrier(conf
);
1179 wait_event(conf
->wait_barrier
,
1180 conf
->reshape_progress
<= bio
->bi_iter
.bi_sector
||
1181 conf
->reshape_progress
>= bio
->bi_iter
.bi_sector
+
1185 if (test_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
) &&
1186 bio_data_dir(bio
) == WRITE
&&
1187 (mddev
->reshape_backwards
1188 ? (bio
->bi_iter
.bi_sector
< conf
->reshape_safe
&&
1189 bio
->bi_iter
.bi_sector
+ sectors
> conf
->reshape_progress
)
1190 : (bio
->bi_iter
.bi_sector
+ sectors
> conf
->reshape_safe
&&
1191 bio
->bi_iter
.bi_sector
< conf
->reshape_progress
))) {
1192 /* Need to update reshape_position in metadata */
1193 mddev
->reshape_position
= conf
->reshape_progress
;
1194 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
1195 set_bit(MD_CHANGE_PENDING
, &mddev
->flags
);
1196 md_wakeup_thread(mddev
->thread
);
1197 wait_event(mddev
->sb_wait
,
1198 !test_bit(MD_CHANGE_PENDING
, &mddev
->flags
));
1200 conf
->reshape_safe
= mddev
->reshape_position
;
1203 r10_bio
= mempool_alloc(conf
->r10bio_pool
, GFP_NOIO
);
1205 r10_bio
->master_bio
= bio
;
1206 r10_bio
->sectors
= sectors
;
1208 r10_bio
->mddev
= mddev
;
1209 r10_bio
->sector
= bio
->bi_iter
.bi_sector
;
1212 /* We might need to issue multiple reads to different
1213 * devices if there are bad blocks around, so we keep
1214 * track of the number of reads in bio->bi_phys_segments.
1215 * If this is 0, there is only one r10_bio and no locking
1216 * will be needed when the request completes. If it is
1217 * non-zero, then it is the number of not-completed requests.
1219 bio
->bi_phys_segments
= 0;
1220 clear_bit(BIO_SEG_VALID
, &bio
->bi_flags
);
1224 * read balancing logic:
1226 struct md_rdev
*rdev
;
1230 rdev
= read_balance(conf
, r10_bio
, &max_sectors
);
1232 raid_end_bio_io(r10_bio
);
1235 slot
= r10_bio
->read_slot
;
1237 read_bio
= bio_clone_mddev(bio
, GFP_NOIO
, mddev
);
1238 bio_trim(read_bio
, r10_bio
->sector
- bio
->bi_iter
.bi_sector
,
1241 r10_bio
->devs
[slot
].bio
= read_bio
;
1242 r10_bio
->devs
[slot
].rdev
= rdev
;
1244 read_bio
->bi_iter
.bi_sector
= r10_bio
->devs
[slot
].addr
+
1245 choose_data_offset(r10_bio
, rdev
);
1246 read_bio
->bi_bdev
= rdev
->bdev
;
1247 read_bio
->bi_end_io
= raid10_end_read_request
;
1248 read_bio
->bi_rw
= READ
| do_sync
;
1249 read_bio
->bi_private
= r10_bio
;
1251 if (max_sectors
< r10_bio
->sectors
) {
1252 /* Could not read all from this device, so we will
1253 * need another r10_bio.
1255 sectors_handled
= (r10_bio
->sector
+ max_sectors
1256 - bio
->bi_iter
.bi_sector
);
1257 r10_bio
->sectors
= max_sectors
;
1258 spin_lock_irq(&conf
->device_lock
);
1259 if (bio
->bi_phys_segments
== 0)
1260 bio
->bi_phys_segments
= 2;
1262 bio
->bi_phys_segments
++;
1263 spin_unlock_irq(&conf
->device_lock
);
1264 /* Cannot call generic_make_request directly
1265 * as that will be queued in __generic_make_request
1266 * and subsequent mempool_alloc might block
1267 * waiting for it. so hand bio over to raid10d.
1269 reschedule_retry(r10_bio
);
1271 r10_bio
= mempool_alloc(conf
->r10bio_pool
, GFP_NOIO
);
1273 r10_bio
->master_bio
= bio
;
1274 r10_bio
->sectors
= bio_sectors(bio
) - sectors_handled
;
1276 r10_bio
->mddev
= mddev
;
1277 r10_bio
->sector
= bio
->bi_iter
.bi_sector
+
1281 generic_make_request(read_bio
);
1288 if (conf
->pending_count
>= max_queued_requests
) {
1289 md_wakeup_thread(mddev
->thread
);
1290 wait_event(conf
->wait_barrier
,
1291 conf
->pending_count
< max_queued_requests
);
1293 /* first select target devices under rcu_lock and
1294 * inc refcount on their rdev. Record them by setting
1296 * If there are known/acknowledged bad blocks on any device
1297 * on which we have seen a write error, we want to avoid
1298 * writing to those blocks. This potentially requires several
1299 * writes to write around the bad blocks. Each set of writes
1300 * gets its own r10_bio with a set of bios attached. The number
1301 * of r10_bios is recored in bio->bi_phys_segments just as with
1305 r10_bio
->read_slot
= -1; /* make sure repl_bio gets freed */
1306 raid10_find_phys(conf
, r10_bio
);
1308 blocked_rdev
= NULL
;
1310 max_sectors
= r10_bio
->sectors
;
1312 for (i
= 0; i
< conf
->copies
; i
++) {
1313 int d
= r10_bio
->devs
[i
].devnum
;
1314 struct md_rdev
*rdev
= rcu_dereference(conf
->mirrors
[d
].rdev
);
1315 struct md_rdev
*rrdev
= rcu_dereference(
1316 conf
->mirrors
[d
].replacement
);
1319 if (rdev
&& unlikely(test_bit(Blocked
, &rdev
->flags
))) {
1320 atomic_inc(&rdev
->nr_pending
);
1321 blocked_rdev
= rdev
;
1324 if (rrdev
&& unlikely(test_bit(Blocked
, &rrdev
->flags
))) {
1325 atomic_inc(&rrdev
->nr_pending
);
1326 blocked_rdev
= rrdev
;
1329 if (rdev
&& (test_bit(Faulty
, &rdev
->flags
)
1330 || test_bit(Unmerged
, &rdev
->flags
)))
1332 if (rrdev
&& (test_bit(Faulty
, &rrdev
->flags
)
1333 || test_bit(Unmerged
, &rrdev
->flags
)))
1336 r10_bio
->devs
[i
].bio
= NULL
;
1337 r10_bio
->devs
[i
].repl_bio
= NULL
;
1339 if (!rdev
&& !rrdev
) {
1340 set_bit(R10BIO_Degraded
, &r10_bio
->state
);
1343 if (rdev
&& test_bit(WriteErrorSeen
, &rdev
->flags
)) {
1345 sector_t dev_sector
= r10_bio
->devs
[i
].addr
;
1349 is_bad
= is_badblock(rdev
, dev_sector
,
1351 &first_bad
, &bad_sectors
);
1353 /* Mustn't write here until the bad block
1356 atomic_inc(&rdev
->nr_pending
);
1357 set_bit(BlockedBadBlocks
, &rdev
->flags
);
1358 blocked_rdev
= rdev
;
1361 if (is_bad
&& first_bad
<= dev_sector
) {
1362 /* Cannot write here at all */
1363 bad_sectors
-= (dev_sector
- first_bad
);
1364 if (bad_sectors
< max_sectors
)
1365 /* Mustn't write more than bad_sectors
1366 * to other devices yet
1368 max_sectors
= bad_sectors
;
1369 /* We don't set R10BIO_Degraded as that
1370 * only applies if the disk is missing,
1371 * so it might be re-added, and we want to
1372 * know to recover this chunk.
1373 * In this case the device is here, and the
1374 * fact that this chunk is not in-sync is
1375 * recorded in the bad block log.
1380 int good_sectors
= first_bad
- dev_sector
;
1381 if (good_sectors
< max_sectors
)
1382 max_sectors
= good_sectors
;
1386 r10_bio
->devs
[i
].bio
= bio
;
1387 atomic_inc(&rdev
->nr_pending
);
1390 r10_bio
->devs
[i
].repl_bio
= bio
;
1391 atomic_inc(&rrdev
->nr_pending
);
1396 if (unlikely(blocked_rdev
)) {
1397 /* Have to wait for this device to get unblocked, then retry */
1401 for (j
= 0; j
< i
; j
++) {
1402 if (r10_bio
->devs
[j
].bio
) {
1403 d
= r10_bio
->devs
[j
].devnum
;
1404 rdev_dec_pending(conf
->mirrors
[d
].rdev
, mddev
);
1406 if (r10_bio
->devs
[j
].repl_bio
) {
1407 struct md_rdev
*rdev
;
1408 d
= r10_bio
->devs
[j
].devnum
;
1409 rdev
= conf
->mirrors
[d
].replacement
;
1411 /* Race with remove_disk */
1413 rdev
= conf
->mirrors
[d
].rdev
;
1415 rdev_dec_pending(rdev
, mddev
);
1418 allow_barrier(conf
);
1419 md_wait_for_blocked_rdev(blocked_rdev
, mddev
);
1424 if (max_sectors
< r10_bio
->sectors
) {
1425 /* We are splitting this into multiple parts, so
1426 * we need to prepare for allocating another r10_bio.
1428 r10_bio
->sectors
= max_sectors
;
1429 spin_lock_irq(&conf
->device_lock
);
1430 if (bio
->bi_phys_segments
== 0)
1431 bio
->bi_phys_segments
= 2;
1433 bio
->bi_phys_segments
++;
1434 spin_unlock_irq(&conf
->device_lock
);
1436 sectors_handled
= r10_bio
->sector
+ max_sectors
-
1437 bio
->bi_iter
.bi_sector
;
1439 atomic_set(&r10_bio
->remaining
, 1);
1440 bitmap_startwrite(mddev
->bitmap
, r10_bio
->sector
, r10_bio
->sectors
, 0);
1442 for (i
= 0; i
< conf
->copies
; i
++) {
1444 int d
= r10_bio
->devs
[i
].devnum
;
1445 if (r10_bio
->devs
[i
].bio
) {
1446 struct md_rdev
*rdev
= conf
->mirrors
[d
].rdev
;
1447 mbio
= bio_clone_mddev(bio
, GFP_NOIO
, mddev
);
1448 bio_trim(mbio
, r10_bio
->sector
- bio
->bi_iter
.bi_sector
,
1450 r10_bio
->devs
[i
].bio
= mbio
;
1452 mbio
->bi_iter
.bi_sector
= (r10_bio
->devs
[i
].addr
+
1453 choose_data_offset(r10_bio
,
1455 mbio
->bi_bdev
= rdev
->bdev
;
1456 mbio
->bi_end_io
= raid10_end_write_request
;
1458 WRITE
| do_sync
| do_fua
| do_discard
| do_same
;
1459 mbio
->bi_private
= r10_bio
;
1461 atomic_inc(&r10_bio
->remaining
);
1463 cb
= blk_check_plugged(raid10_unplug
, mddev
,
1466 plug
= container_of(cb
, struct raid10_plug_cb
,
1470 spin_lock_irqsave(&conf
->device_lock
, flags
);
1472 bio_list_add(&plug
->pending
, mbio
);
1473 plug
->pending_cnt
++;
1475 bio_list_add(&conf
->pending_bio_list
, mbio
);
1476 conf
->pending_count
++;
1478 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
1480 md_wakeup_thread(mddev
->thread
);
1483 if (r10_bio
->devs
[i
].repl_bio
) {
1484 struct md_rdev
*rdev
= conf
->mirrors
[d
].replacement
;
1486 /* Replacement just got moved to main 'rdev' */
1488 rdev
= conf
->mirrors
[d
].rdev
;
1490 mbio
= bio_clone_mddev(bio
, GFP_NOIO
, mddev
);
1491 bio_trim(mbio
, r10_bio
->sector
- bio
->bi_iter
.bi_sector
,
1493 r10_bio
->devs
[i
].repl_bio
= mbio
;
1495 mbio
->bi_iter
.bi_sector
= (r10_bio
->devs
[i
].addr
+
1498 mbio
->bi_bdev
= rdev
->bdev
;
1499 mbio
->bi_end_io
= raid10_end_write_request
;
1501 WRITE
| do_sync
| do_fua
| do_discard
| do_same
;
1502 mbio
->bi_private
= r10_bio
;
1504 atomic_inc(&r10_bio
->remaining
);
1505 spin_lock_irqsave(&conf
->device_lock
, flags
);
1506 bio_list_add(&conf
->pending_bio_list
, mbio
);
1507 conf
->pending_count
++;
1508 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
1509 if (!mddev_check_plugged(mddev
))
1510 md_wakeup_thread(mddev
->thread
);
1514 /* Don't remove the bias on 'remaining' (one_write_done) until
1515 * after checking if we need to go around again.
1518 if (sectors_handled
< bio_sectors(bio
)) {
1519 one_write_done(r10_bio
);
1520 /* We need another r10_bio. It has already been counted
1521 * in bio->bi_phys_segments.
1523 r10_bio
= mempool_alloc(conf
->r10bio_pool
, GFP_NOIO
);
1525 r10_bio
->master_bio
= bio
;
1526 r10_bio
->sectors
= bio_sectors(bio
) - sectors_handled
;
1528 r10_bio
->mddev
= mddev
;
1529 r10_bio
->sector
= bio
->bi_iter
.bi_sector
+ sectors_handled
;
1533 one_write_done(r10_bio
);
1536 static void make_request(struct mddev
*mddev
, struct bio
*bio
)
1538 struct r10conf
*conf
= mddev
->private;
1539 sector_t chunk_mask
= (conf
->geo
.chunk_mask
& conf
->prev
.chunk_mask
);
1540 int chunk_sects
= chunk_mask
+ 1;
1544 if (unlikely(bio
->bi_rw
& REQ_FLUSH
)) {
1545 md_flush_request(mddev
, bio
);
1549 md_write_start(mddev
, bio
);
1554 * If this request crosses a chunk boundary, we need to split
1557 if (unlikely((bio
->bi_iter
.bi_sector
& chunk_mask
) +
1558 bio_sectors(bio
) > chunk_sects
1559 && (conf
->geo
.near_copies
< conf
->geo
.raid_disks
1560 || conf
->prev
.near_copies
<
1561 conf
->prev
.raid_disks
))) {
1562 split
= bio_split(bio
, chunk_sects
-
1563 (bio
->bi_iter
.bi_sector
&
1565 GFP_NOIO
, fs_bio_set
);
1566 bio_chain(split
, bio
);
1571 __make_request(mddev
, split
);
1572 } while (split
!= bio
);
1574 /* In case raid10d snuck in to freeze_array */
1575 wake_up(&conf
->wait_barrier
);
1578 static void status(struct seq_file
*seq
, struct mddev
*mddev
)
1580 struct r10conf
*conf
= mddev
->private;
1583 if (conf
->geo
.near_copies
< conf
->geo
.raid_disks
)
1584 seq_printf(seq
, " %dK chunks", mddev
->chunk_sectors
/ 2);
1585 if (conf
->geo
.near_copies
> 1)
1586 seq_printf(seq
, " %d near-copies", conf
->geo
.near_copies
);
1587 if (conf
->geo
.far_copies
> 1) {
1588 if (conf
->geo
.far_offset
)
1589 seq_printf(seq
, " %d offset-copies", conf
->geo
.far_copies
);
1591 seq_printf(seq
, " %d far-copies", conf
->geo
.far_copies
);
1593 seq_printf(seq
, " [%d/%d] [", conf
->geo
.raid_disks
,
1594 conf
->geo
.raid_disks
- mddev
->degraded
);
1595 for (i
= 0; i
< conf
->geo
.raid_disks
; i
++)
1596 seq_printf(seq
, "%s",
1597 conf
->mirrors
[i
].rdev
&&
1598 test_bit(In_sync
, &conf
->mirrors
[i
].rdev
->flags
) ? "U" : "_");
1599 seq_printf(seq
, "]");
1602 /* check if there are enough drives for
1603 * every block to appear on atleast one.
1604 * Don't consider the device numbered 'ignore'
1605 * as we might be about to remove it.
1607 static int _enough(struct r10conf
*conf
, int previous
, int ignore
)
1613 disks
= conf
->prev
.raid_disks
;
1614 ncopies
= conf
->prev
.near_copies
;
1616 disks
= conf
->geo
.raid_disks
;
1617 ncopies
= conf
->geo
.near_copies
;
1622 int n
= conf
->copies
;
1626 struct md_rdev
*rdev
;
1627 if (this != ignore
&&
1628 (rdev
= rcu_dereference(conf
->mirrors
[this].rdev
)) &&
1629 test_bit(In_sync
, &rdev
->flags
))
1631 this = (this+1) % disks
;
1635 first
= (first
+ ncopies
) % disks
;
1636 } while (first
!= 0);
1643 static int enough(struct r10conf
*conf
, int ignore
)
1645 /* when calling 'enough', both 'prev' and 'geo' must
1647 * This is ensured if ->reconfig_mutex or ->device_lock
1650 return _enough(conf
, 0, ignore
) &&
1651 _enough(conf
, 1, ignore
);
1654 static void error(struct mddev
*mddev
, struct md_rdev
*rdev
)
1656 char b
[BDEVNAME_SIZE
];
1657 struct r10conf
*conf
= mddev
->private;
1658 unsigned long flags
;
1661 * If it is not operational, then we have already marked it as dead
1662 * else if it is the last working disks, ignore the error, let the
1663 * next level up know.
1664 * else mark the drive as failed
1666 spin_lock_irqsave(&conf
->device_lock
, flags
);
1667 if (test_bit(In_sync
, &rdev
->flags
)
1668 && !enough(conf
, rdev
->raid_disk
)) {
1670 * Don't fail the drive, just return an IO error.
1672 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
1675 if (test_and_clear_bit(In_sync
, &rdev
->flags
))
1678 * If recovery is running, make sure it aborts.
1680 set_bit(MD_RECOVERY_INTR
, &mddev
->recovery
);
1681 set_bit(Blocked
, &rdev
->flags
);
1682 set_bit(Faulty
, &rdev
->flags
);
1683 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
1684 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
1686 "md/raid10:%s: Disk failure on %s, disabling device.\n"
1687 "md/raid10:%s: Operation continuing on %d devices.\n",
1688 mdname(mddev
), bdevname(rdev
->bdev
, b
),
1689 mdname(mddev
), conf
->geo
.raid_disks
- mddev
->degraded
);
1692 static void print_conf(struct r10conf
*conf
)
1695 struct raid10_info
*tmp
;
1697 printk(KERN_DEBUG
"RAID10 conf printout:\n");
1699 printk(KERN_DEBUG
"(!conf)\n");
1702 printk(KERN_DEBUG
" --- wd:%d rd:%d\n", conf
->geo
.raid_disks
- conf
->mddev
->degraded
,
1703 conf
->geo
.raid_disks
);
1705 for (i
= 0; i
< conf
->geo
.raid_disks
; i
++) {
1706 char b
[BDEVNAME_SIZE
];
1707 tmp
= conf
->mirrors
+ i
;
1709 printk(KERN_DEBUG
" disk %d, wo:%d, o:%d, dev:%s\n",
1710 i
, !test_bit(In_sync
, &tmp
->rdev
->flags
),
1711 !test_bit(Faulty
, &tmp
->rdev
->flags
),
1712 bdevname(tmp
->rdev
->bdev
,b
));
1716 static void close_sync(struct r10conf
*conf
)
1719 allow_barrier(conf
);
1721 mempool_destroy(conf
->r10buf_pool
);
1722 conf
->r10buf_pool
= NULL
;
1725 static int raid10_spare_active(struct mddev
*mddev
)
1728 struct r10conf
*conf
= mddev
->private;
1729 struct raid10_info
*tmp
;
1731 unsigned long flags
;
1734 * Find all non-in_sync disks within the RAID10 configuration
1735 * and mark them in_sync
1737 for (i
= 0; i
< conf
->geo
.raid_disks
; i
++) {
1738 tmp
= conf
->mirrors
+ i
;
1739 if (tmp
->replacement
1740 && tmp
->replacement
->recovery_offset
== MaxSector
1741 && !test_bit(Faulty
, &tmp
->replacement
->flags
)
1742 && !test_and_set_bit(In_sync
, &tmp
->replacement
->flags
)) {
1743 /* Replacement has just become active */
1745 || !test_and_clear_bit(In_sync
, &tmp
->rdev
->flags
))
1748 /* Replaced device not technically faulty,
1749 * but we need to be sure it gets removed
1750 * and never re-added.
1752 set_bit(Faulty
, &tmp
->rdev
->flags
);
1753 sysfs_notify_dirent_safe(
1754 tmp
->rdev
->sysfs_state
);
1756 sysfs_notify_dirent_safe(tmp
->replacement
->sysfs_state
);
1757 } else if (tmp
->rdev
1758 && tmp
->rdev
->recovery_offset
== MaxSector
1759 && !test_bit(Faulty
, &tmp
->rdev
->flags
)
1760 && !test_and_set_bit(In_sync
, &tmp
->rdev
->flags
)) {
1762 sysfs_notify_dirent_safe(tmp
->rdev
->sysfs_state
);
1765 spin_lock_irqsave(&conf
->device_lock
, flags
);
1766 mddev
->degraded
-= count
;
1767 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
1773 static int raid10_add_disk(struct mddev
*mddev
, struct md_rdev
*rdev
)
1775 struct r10conf
*conf
= mddev
->private;
1779 int last
= conf
->geo
.raid_disks
- 1;
1780 struct request_queue
*q
= bdev_get_queue(rdev
->bdev
);
1782 if (mddev
->recovery_cp
< MaxSector
)
1783 /* only hot-add to in-sync arrays, as recovery is
1784 * very different from resync
1787 if (rdev
->saved_raid_disk
< 0 && !_enough(conf
, 1, -1))
1790 if (rdev
->raid_disk
>= 0)
1791 first
= last
= rdev
->raid_disk
;
1793 if (q
->merge_bvec_fn
) {
1794 set_bit(Unmerged
, &rdev
->flags
);
1795 mddev
->merge_check_needed
= 1;
1798 if (rdev
->saved_raid_disk
>= first
&&
1799 conf
->mirrors
[rdev
->saved_raid_disk
].rdev
== NULL
)
1800 mirror
= rdev
->saved_raid_disk
;
1803 for ( ; mirror
<= last
; mirror
++) {
1804 struct raid10_info
*p
= &conf
->mirrors
[mirror
];
1805 if (p
->recovery_disabled
== mddev
->recovery_disabled
)
1808 if (!test_bit(WantReplacement
, &p
->rdev
->flags
) ||
1809 p
->replacement
!= NULL
)
1811 clear_bit(In_sync
, &rdev
->flags
);
1812 set_bit(Replacement
, &rdev
->flags
);
1813 rdev
->raid_disk
= mirror
;
1816 disk_stack_limits(mddev
->gendisk
, rdev
->bdev
,
1817 rdev
->data_offset
<< 9);
1819 rcu_assign_pointer(p
->replacement
, rdev
);
1824 disk_stack_limits(mddev
->gendisk
, rdev
->bdev
,
1825 rdev
->data_offset
<< 9);
1827 p
->head_position
= 0;
1828 p
->recovery_disabled
= mddev
->recovery_disabled
- 1;
1829 rdev
->raid_disk
= mirror
;
1831 if (rdev
->saved_raid_disk
!= mirror
)
1833 rcu_assign_pointer(p
->rdev
, rdev
);
1836 if (err
== 0 && test_bit(Unmerged
, &rdev
->flags
)) {
1837 /* Some requests might not have seen this new
1838 * merge_bvec_fn. We must wait for them to complete
1839 * before merging the device fully.
1840 * First we make sure any code which has tested
1841 * our function has submitted the request, then
1842 * we wait for all outstanding requests to complete.
1844 synchronize_sched();
1845 freeze_array(conf
, 0);
1846 unfreeze_array(conf
);
1847 clear_bit(Unmerged
, &rdev
->flags
);
1849 md_integrity_add_rdev(rdev
, mddev
);
1850 if (mddev
->queue
&& blk_queue_discard(bdev_get_queue(rdev
->bdev
)))
1851 queue_flag_set_unlocked(QUEUE_FLAG_DISCARD
, mddev
->queue
);
1857 static int raid10_remove_disk(struct mddev
*mddev
, struct md_rdev
*rdev
)
1859 struct r10conf
*conf
= mddev
->private;
1861 int number
= rdev
->raid_disk
;
1862 struct md_rdev
**rdevp
;
1863 struct raid10_info
*p
= conf
->mirrors
+ number
;
1866 if (rdev
== p
->rdev
)
1868 else if (rdev
== p
->replacement
)
1869 rdevp
= &p
->replacement
;
1873 if (test_bit(In_sync
, &rdev
->flags
) ||
1874 atomic_read(&rdev
->nr_pending
)) {
1878 /* Only remove faulty devices if recovery
1881 if (!test_bit(Faulty
, &rdev
->flags
) &&
1882 mddev
->recovery_disabled
!= p
->recovery_disabled
&&
1883 (!p
->replacement
|| p
->replacement
== rdev
) &&
1884 number
< conf
->geo
.raid_disks
&&
1891 if (atomic_read(&rdev
->nr_pending
)) {
1892 /* lost the race, try later */
1896 } else if (p
->replacement
) {
1897 /* We must have just cleared 'rdev' */
1898 p
->rdev
= p
->replacement
;
1899 clear_bit(Replacement
, &p
->replacement
->flags
);
1900 smp_mb(); /* Make sure other CPUs may see both as identical
1901 * but will never see neither -- if they are careful.
1903 p
->replacement
= NULL
;
1904 clear_bit(WantReplacement
, &rdev
->flags
);
1906 /* We might have just remove the Replacement as faulty
1907 * Clear the flag just in case
1909 clear_bit(WantReplacement
, &rdev
->flags
);
1911 err
= md_integrity_register(mddev
);
1919 static void end_sync_read(struct bio
*bio
, int error
)
1921 struct r10bio
*r10_bio
= bio
->bi_private
;
1922 struct r10conf
*conf
= r10_bio
->mddev
->private;
1925 if (bio
== r10_bio
->master_bio
) {
1926 /* this is a reshape read */
1927 d
= r10_bio
->read_slot
; /* really the read dev */
1929 d
= find_bio_disk(conf
, r10_bio
, bio
, NULL
, NULL
);
1931 if (test_bit(BIO_UPTODATE
, &bio
->bi_flags
))
1932 set_bit(R10BIO_Uptodate
, &r10_bio
->state
);
1934 /* The write handler will notice the lack of
1935 * R10BIO_Uptodate and record any errors etc
1937 atomic_add(r10_bio
->sectors
,
1938 &conf
->mirrors
[d
].rdev
->corrected_errors
);
1940 /* for reconstruct, we always reschedule after a read.
1941 * for resync, only after all reads
1943 rdev_dec_pending(conf
->mirrors
[d
].rdev
, conf
->mddev
);
1944 if (test_bit(R10BIO_IsRecover
, &r10_bio
->state
) ||
1945 atomic_dec_and_test(&r10_bio
->remaining
)) {
1946 /* we have read all the blocks,
1947 * do the comparison in process context in raid10d
1949 reschedule_retry(r10_bio
);
1953 static void end_sync_request(struct r10bio
*r10_bio
)
1955 struct mddev
*mddev
= r10_bio
->mddev
;
1957 while (atomic_dec_and_test(&r10_bio
->remaining
)) {
1958 if (r10_bio
->master_bio
== NULL
) {
1959 /* the primary of several recovery bios */
1960 sector_t s
= r10_bio
->sectors
;
1961 if (test_bit(R10BIO_MadeGood
, &r10_bio
->state
) ||
1962 test_bit(R10BIO_WriteError
, &r10_bio
->state
))
1963 reschedule_retry(r10_bio
);
1966 md_done_sync(mddev
, s
, 1);
1969 struct r10bio
*r10_bio2
= (struct r10bio
*)r10_bio
->master_bio
;
1970 if (test_bit(R10BIO_MadeGood
, &r10_bio
->state
) ||
1971 test_bit(R10BIO_WriteError
, &r10_bio
->state
))
1972 reschedule_retry(r10_bio
);
1980 static void end_sync_write(struct bio
*bio
, int error
)
1982 int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
1983 struct r10bio
*r10_bio
= bio
->bi_private
;
1984 struct mddev
*mddev
= r10_bio
->mddev
;
1985 struct r10conf
*conf
= mddev
->private;
1991 struct md_rdev
*rdev
= NULL
;
1993 d
= find_bio_disk(conf
, r10_bio
, bio
, &slot
, &repl
);
1995 rdev
= conf
->mirrors
[d
].replacement
;
1997 rdev
= conf
->mirrors
[d
].rdev
;
2001 md_error(mddev
, rdev
);
2003 set_bit(WriteErrorSeen
, &rdev
->flags
);
2004 if (!test_and_set_bit(WantReplacement
, &rdev
->flags
))
2005 set_bit(MD_RECOVERY_NEEDED
,
2006 &rdev
->mddev
->recovery
);
2007 set_bit(R10BIO_WriteError
, &r10_bio
->state
);
2009 } else if (is_badblock(rdev
,
2010 r10_bio
->devs
[slot
].addr
,
2012 &first_bad
, &bad_sectors
))
2013 set_bit(R10BIO_MadeGood
, &r10_bio
->state
);
2015 rdev_dec_pending(rdev
, mddev
);
2017 end_sync_request(r10_bio
);
2021 * Note: sync and recover and handled very differently for raid10
2022 * This code is for resync.
2023 * For resync, we read through virtual addresses and read all blocks.
2024 * If there is any error, we schedule a write. The lowest numbered
2025 * drive is authoritative.
2026 * However requests come for physical address, so we need to map.
2027 * For every physical address there are raid_disks/copies virtual addresses,
2028 * which is always are least one, but is not necessarly an integer.
2029 * This means that a physical address can span multiple chunks, so we may
2030 * have to submit multiple io requests for a single sync request.
2033 * We check if all blocks are in-sync and only write to blocks that
2036 static void sync_request_write(struct mddev
*mddev
, struct r10bio
*r10_bio
)
2038 struct r10conf
*conf
= mddev
->private;
2040 struct bio
*tbio
, *fbio
;
2043 atomic_set(&r10_bio
->remaining
, 1);
2045 /* find the first device with a block */
2046 for (i
=0; i
<conf
->copies
; i
++)
2047 if (test_bit(BIO_UPTODATE
, &r10_bio
->devs
[i
].bio
->bi_flags
))
2050 if (i
== conf
->copies
)
2054 fbio
= r10_bio
->devs
[i
].bio
;
2056 vcnt
= (r10_bio
->sectors
+ (PAGE_SIZE
>> 9) - 1) >> (PAGE_SHIFT
- 9);
2057 /* now find blocks with errors */
2058 for (i
=0 ; i
< conf
->copies
; i
++) {
2061 tbio
= r10_bio
->devs
[i
].bio
;
2063 if (tbio
->bi_end_io
!= end_sync_read
)
2067 if (test_bit(BIO_UPTODATE
, &r10_bio
->devs
[i
].bio
->bi_flags
)) {
2068 /* We know that the bi_io_vec layout is the same for
2069 * both 'first' and 'i', so we just compare them.
2070 * All vec entries are PAGE_SIZE;
2072 int sectors
= r10_bio
->sectors
;
2073 for (j
= 0; j
< vcnt
; j
++) {
2074 int len
= PAGE_SIZE
;
2075 if (sectors
< (len
/ 512))
2076 len
= sectors
* 512;
2077 if (memcmp(page_address(fbio
->bi_io_vec
[j
].bv_page
),
2078 page_address(tbio
->bi_io_vec
[j
].bv_page
),
2085 atomic64_add(r10_bio
->sectors
, &mddev
->resync_mismatches
);
2086 if (test_bit(MD_RECOVERY_CHECK
, &mddev
->recovery
))
2087 /* Don't fix anything. */
2090 /* Ok, we need to write this bio, either to correct an
2091 * inconsistency or to correct an unreadable block.
2092 * First we need to fixup bv_offset, bv_len and
2093 * bi_vecs, as the read request might have corrupted these
2097 tbio
->bi_vcnt
= vcnt
;
2098 tbio
->bi_iter
.bi_size
= r10_bio
->sectors
<< 9;
2099 tbio
->bi_rw
= WRITE
;
2100 tbio
->bi_private
= r10_bio
;
2101 tbio
->bi_iter
.bi_sector
= r10_bio
->devs
[i
].addr
;
2102 tbio
->bi_end_io
= end_sync_write
;
2104 bio_copy_data(tbio
, fbio
);
2106 d
= r10_bio
->devs
[i
].devnum
;
2107 atomic_inc(&conf
->mirrors
[d
].rdev
->nr_pending
);
2108 atomic_inc(&r10_bio
->remaining
);
2109 md_sync_acct(conf
->mirrors
[d
].rdev
->bdev
, bio_sectors(tbio
));
2111 tbio
->bi_iter
.bi_sector
+= conf
->mirrors
[d
].rdev
->data_offset
;
2112 tbio
->bi_bdev
= conf
->mirrors
[d
].rdev
->bdev
;
2113 generic_make_request(tbio
);
2116 /* Now write out to any replacement devices
2119 for (i
= 0; i
< conf
->copies
; i
++) {
2122 tbio
= r10_bio
->devs
[i
].repl_bio
;
2123 if (!tbio
|| !tbio
->bi_end_io
)
2125 if (r10_bio
->devs
[i
].bio
->bi_end_io
!= end_sync_write
2126 && r10_bio
->devs
[i
].bio
!= fbio
)
2127 bio_copy_data(tbio
, fbio
);
2128 d
= r10_bio
->devs
[i
].devnum
;
2129 atomic_inc(&r10_bio
->remaining
);
2130 md_sync_acct(conf
->mirrors
[d
].replacement
->bdev
,
2132 generic_make_request(tbio
);
2136 if (atomic_dec_and_test(&r10_bio
->remaining
)) {
2137 md_done_sync(mddev
, r10_bio
->sectors
, 1);
2143 * Now for the recovery code.
2144 * Recovery happens across physical sectors.
2145 * We recover all non-is_sync drives by finding the virtual address of
2146 * each, and then choose a working drive that also has that virt address.
2147 * There is a separate r10_bio for each non-in_sync drive.
2148 * Only the first two slots are in use. The first for reading,
2149 * The second for writing.
2152 static void fix_recovery_read_error(struct r10bio
*r10_bio
)
2154 /* We got a read error during recovery.
2155 * We repeat the read in smaller page-sized sections.
2156 * If a read succeeds, write it to the new device or record
2157 * a bad block if we cannot.
2158 * If a read fails, record a bad block on both old and
2161 struct mddev
*mddev
= r10_bio
->mddev
;
2162 struct r10conf
*conf
= mddev
->private;
2163 struct bio
*bio
= r10_bio
->devs
[0].bio
;
2165 int sectors
= r10_bio
->sectors
;
2167 int dr
= r10_bio
->devs
[0].devnum
;
2168 int dw
= r10_bio
->devs
[1].devnum
;
2172 struct md_rdev
*rdev
;
2176 if (s
> (PAGE_SIZE
>>9))
2179 rdev
= conf
->mirrors
[dr
].rdev
;
2180 addr
= r10_bio
->devs
[0].addr
+ sect
,
2181 ok
= sync_page_io(rdev
,
2184 bio
->bi_io_vec
[idx
].bv_page
,
2187 rdev
= conf
->mirrors
[dw
].rdev
;
2188 addr
= r10_bio
->devs
[1].addr
+ sect
;
2189 ok
= sync_page_io(rdev
,
2192 bio
->bi_io_vec
[idx
].bv_page
,
2195 set_bit(WriteErrorSeen
, &rdev
->flags
);
2196 if (!test_and_set_bit(WantReplacement
,
2198 set_bit(MD_RECOVERY_NEEDED
,
2199 &rdev
->mddev
->recovery
);
2203 /* We don't worry if we cannot set a bad block -
2204 * it really is bad so there is no loss in not
2207 rdev_set_badblocks(rdev
, addr
, s
, 0);
2209 if (rdev
!= conf
->mirrors
[dw
].rdev
) {
2210 /* need bad block on destination too */
2211 struct md_rdev
*rdev2
= conf
->mirrors
[dw
].rdev
;
2212 addr
= r10_bio
->devs
[1].addr
+ sect
;
2213 ok
= rdev_set_badblocks(rdev2
, addr
, s
, 0);
2215 /* just abort the recovery */
2217 "md/raid10:%s: recovery aborted"
2218 " due to read error\n",
2221 conf
->mirrors
[dw
].recovery_disabled
2222 = mddev
->recovery_disabled
;
2223 set_bit(MD_RECOVERY_INTR
,
2236 static void recovery_request_write(struct mddev
*mddev
, struct r10bio
*r10_bio
)
2238 struct r10conf
*conf
= mddev
->private;
2240 struct bio
*wbio
, *wbio2
;
2242 if (!test_bit(R10BIO_Uptodate
, &r10_bio
->state
)) {
2243 fix_recovery_read_error(r10_bio
);
2244 end_sync_request(r10_bio
);
2249 * share the pages with the first bio
2250 * and submit the write request
2252 d
= r10_bio
->devs
[1].devnum
;
2253 wbio
= r10_bio
->devs
[1].bio
;
2254 wbio2
= r10_bio
->devs
[1].repl_bio
;
2255 /* Need to test wbio2->bi_end_io before we call
2256 * generic_make_request as if the former is NULL,
2257 * the latter is free to free wbio2.
2259 if (wbio2
&& !wbio2
->bi_end_io
)
2261 if (wbio
->bi_end_io
) {
2262 atomic_inc(&conf
->mirrors
[d
].rdev
->nr_pending
);
2263 md_sync_acct(conf
->mirrors
[d
].rdev
->bdev
, bio_sectors(wbio
));
2264 generic_make_request(wbio
);
2267 atomic_inc(&conf
->mirrors
[d
].replacement
->nr_pending
);
2268 md_sync_acct(conf
->mirrors
[d
].replacement
->bdev
,
2269 bio_sectors(wbio2
));
2270 generic_make_request(wbio2
);
2275 * Used by fix_read_error() to decay the per rdev read_errors.
2276 * We halve the read error count for every hour that has elapsed
2277 * since the last recorded read error.
2280 static void check_decay_read_errors(struct mddev
*mddev
, struct md_rdev
*rdev
)
2282 struct timespec cur_time_mon
;
2283 unsigned long hours_since_last
;
2284 unsigned int read_errors
= atomic_read(&rdev
->read_errors
);
2286 ktime_get_ts(&cur_time_mon
);
2288 if (rdev
->last_read_error
.tv_sec
== 0 &&
2289 rdev
->last_read_error
.tv_nsec
== 0) {
2290 /* first time we've seen a read error */
2291 rdev
->last_read_error
= cur_time_mon
;
2295 hours_since_last
= (cur_time_mon
.tv_sec
-
2296 rdev
->last_read_error
.tv_sec
) / 3600;
2298 rdev
->last_read_error
= cur_time_mon
;
2301 * if hours_since_last is > the number of bits in read_errors
2302 * just set read errors to 0. We do this to avoid
2303 * overflowing the shift of read_errors by hours_since_last.
2305 if (hours_since_last
>= 8 * sizeof(read_errors
))
2306 atomic_set(&rdev
->read_errors
, 0);
2308 atomic_set(&rdev
->read_errors
, read_errors
>> hours_since_last
);
2311 static int r10_sync_page_io(struct md_rdev
*rdev
, sector_t sector
,
2312 int sectors
, struct page
*page
, int rw
)
2317 if (is_badblock(rdev
, sector
, sectors
, &first_bad
, &bad_sectors
)
2318 && (rw
== READ
|| test_bit(WriteErrorSeen
, &rdev
->flags
)))
2320 if (sync_page_io(rdev
, sector
, sectors
<< 9, page
, rw
, false))
2324 set_bit(WriteErrorSeen
, &rdev
->flags
);
2325 if (!test_and_set_bit(WantReplacement
, &rdev
->flags
))
2326 set_bit(MD_RECOVERY_NEEDED
,
2327 &rdev
->mddev
->recovery
);
2329 /* need to record an error - either for the block or the device */
2330 if (!rdev_set_badblocks(rdev
, sector
, sectors
, 0))
2331 md_error(rdev
->mddev
, rdev
);
2336 * This is a kernel thread which:
2338 * 1. Retries failed read operations on working mirrors.
2339 * 2. Updates the raid superblock when problems encounter.
2340 * 3. Performs writes following reads for array synchronising.
2343 static void fix_read_error(struct r10conf
*conf
, struct mddev
*mddev
, struct r10bio
*r10_bio
)
2345 int sect
= 0; /* Offset from r10_bio->sector */
2346 int sectors
= r10_bio
->sectors
;
2347 struct md_rdev
*rdev
;
2348 int max_read_errors
= atomic_read(&mddev
->max_corr_read_errors
);
2349 int d
= r10_bio
->devs
[r10_bio
->read_slot
].devnum
;
2351 /* still own a reference to this rdev, so it cannot
2352 * have been cleared recently.
2354 rdev
= conf
->mirrors
[d
].rdev
;
2356 if (test_bit(Faulty
, &rdev
->flags
))
2357 /* drive has already been failed, just ignore any
2358 more fix_read_error() attempts */
2361 check_decay_read_errors(mddev
, rdev
);
2362 atomic_inc(&rdev
->read_errors
);
2363 if (atomic_read(&rdev
->read_errors
) > max_read_errors
) {
2364 char b
[BDEVNAME_SIZE
];
2365 bdevname(rdev
->bdev
, b
);
2368 "md/raid10:%s: %s: Raid device exceeded "
2369 "read_error threshold [cur %d:max %d]\n",
2371 atomic_read(&rdev
->read_errors
), max_read_errors
);
2373 "md/raid10:%s: %s: Failing raid device\n",
2375 md_error(mddev
, conf
->mirrors
[d
].rdev
);
2376 r10_bio
->devs
[r10_bio
->read_slot
].bio
= IO_BLOCKED
;
2382 int sl
= r10_bio
->read_slot
;
2386 if (s
> (PAGE_SIZE
>>9))
2394 d
= r10_bio
->devs
[sl
].devnum
;
2395 rdev
= rcu_dereference(conf
->mirrors
[d
].rdev
);
2397 !test_bit(Unmerged
, &rdev
->flags
) &&
2398 test_bit(In_sync
, &rdev
->flags
) &&
2399 is_badblock(rdev
, r10_bio
->devs
[sl
].addr
+ sect
, s
,
2400 &first_bad
, &bad_sectors
) == 0) {
2401 atomic_inc(&rdev
->nr_pending
);
2403 success
= sync_page_io(rdev
,
2404 r10_bio
->devs
[sl
].addr
+
2407 conf
->tmppage
, READ
, false);
2408 rdev_dec_pending(rdev
, mddev
);
2414 if (sl
== conf
->copies
)
2416 } while (!success
&& sl
!= r10_bio
->read_slot
);
2420 /* Cannot read from anywhere, just mark the block
2421 * as bad on the first device to discourage future
2424 int dn
= r10_bio
->devs
[r10_bio
->read_slot
].devnum
;
2425 rdev
= conf
->mirrors
[dn
].rdev
;
2427 if (!rdev_set_badblocks(
2429 r10_bio
->devs
[r10_bio
->read_slot
].addr
2432 md_error(mddev
, rdev
);
2433 r10_bio
->devs
[r10_bio
->read_slot
].bio
2440 /* write it back and re-read */
2442 while (sl
!= r10_bio
->read_slot
) {
2443 char b
[BDEVNAME_SIZE
];
2448 d
= r10_bio
->devs
[sl
].devnum
;
2449 rdev
= rcu_dereference(conf
->mirrors
[d
].rdev
);
2451 test_bit(Unmerged
, &rdev
->flags
) ||
2452 !test_bit(In_sync
, &rdev
->flags
))
2455 atomic_inc(&rdev
->nr_pending
);
2457 if (r10_sync_page_io(rdev
,
2458 r10_bio
->devs
[sl
].addr
+
2460 s
, conf
->tmppage
, WRITE
)
2462 /* Well, this device is dead */
2464 "md/raid10:%s: read correction "
2466 " (%d sectors at %llu on %s)\n",
2468 (unsigned long long)(
2470 choose_data_offset(r10_bio
,
2472 bdevname(rdev
->bdev
, b
));
2473 printk(KERN_NOTICE
"md/raid10:%s: %s: failing "
2476 bdevname(rdev
->bdev
, b
));
2478 rdev_dec_pending(rdev
, mddev
);
2482 while (sl
!= r10_bio
->read_slot
) {
2483 char b
[BDEVNAME_SIZE
];
2488 d
= r10_bio
->devs
[sl
].devnum
;
2489 rdev
= rcu_dereference(conf
->mirrors
[d
].rdev
);
2491 !test_bit(In_sync
, &rdev
->flags
))
2494 atomic_inc(&rdev
->nr_pending
);
2496 switch (r10_sync_page_io(rdev
,
2497 r10_bio
->devs
[sl
].addr
+
2502 /* Well, this device is dead */
2504 "md/raid10:%s: unable to read back "
2506 " (%d sectors at %llu on %s)\n",
2508 (unsigned long long)(
2510 choose_data_offset(r10_bio
, rdev
)),
2511 bdevname(rdev
->bdev
, b
));
2512 printk(KERN_NOTICE
"md/raid10:%s: %s: failing "
2515 bdevname(rdev
->bdev
, b
));
2519 "md/raid10:%s: read error corrected"
2520 " (%d sectors at %llu on %s)\n",
2522 (unsigned long long)(
2524 choose_data_offset(r10_bio
, rdev
)),
2525 bdevname(rdev
->bdev
, b
));
2526 atomic_add(s
, &rdev
->corrected_errors
);
2529 rdev_dec_pending(rdev
, mddev
);
2539 static int narrow_write_error(struct r10bio
*r10_bio
, int i
)
2541 struct bio
*bio
= r10_bio
->master_bio
;
2542 struct mddev
*mddev
= r10_bio
->mddev
;
2543 struct r10conf
*conf
= mddev
->private;
2544 struct md_rdev
*rdev
= conf
->mirrors
[r10_bio
->devs
[i
].devnum
].rdev
;
2545 /* bio has the data to be written to slot 'i' where
2546 * we just recently had a write error.
2547 * We repeatedly clone the bio and trim down to one block,
2548 * then try the write. Where the write fails we record
2550 * It is conceivable that the bio doesn't exactly align with
2551 * blocks. We must handle this.
2553 * We currently own a reference to the rdev.
2559 int sect_to_write
= r10_bio
->sectors
;
2562 if (rdev
->badblocks
.shift
< 0)
2565 block_sectors
= roundup(1 << rdev
->badblocks
.shift
,
2566 bdev_logical_block_size(rdev
->bdev
) >> 9);
2567 sector
= r10_bio
->sector
;
2568 sectors
= ((r10_bio
->sector
+ block_sectors
)
2569 & ~(sector_t
)(block_sectors
- 1))
2572 while (sect_to_write
) {
2574 if (sectors
> sect_to_write
)
2575 sectors
= sect_to_write
;
2576 /* Write at 'sector' for 'sectors' */
2577 wbio
= bio_clone_mddev(bio
, GFP_NOIO
, mddev
);
2578 bio_trim(wbio
, sector
- bio
->bi_iter
.bi_sector
, sectors
);
2579 wbio
->bi_iter
.bi_sector
= (r10_bio
->devs
[i
].addr
+
2580 choose_data_offset(r10_bio
, rdev
) +
2581 (sector
- r10_bio
->sector
));
2582 wbio
->bi_bdev
= rdev
->bdev
;
2583 if (submit_bio_wait(WRITE
, wbio
) == 0)
2585 ok
= rdev_set_badblocks(rdev
, sector
,
2590 sect_to_write
-= sectors
;
2592 sectors
= block_sectors
;
2597 static void handle_read_error(struct mddev
*mddev
, struct r10bio
*r10_bio
)
2599 int slot
= r10_bio
->read_slot
;
2601 struct r10conf
*conf
= mddev
->private;
2602 struct md_rdev
*rdev
= r10_bio
->devs
[slot
].rdev
;
2603 char b
[BDEVNAME_SIZE
];
2604 unsigned long do_sync
;
2607 /* we got a read error. Maybe the drive is bad. Maybe just
2608 * the block and we can fix it.
2609 * We freeze all other IO, and try reading the block from
2610 * other devices. When we find one, we re-write
2611 * and check it that fixes the read error.
2612 * This is all done synchronously while the array is
2615 bio
= r10_bio
->devs
[slot
].bio
;
2616 bdevname(bio
->bi_bdev
, b
);
2618 r10_bio
->devs
[slot
].bio
= NULL
;
2620 if (mddev
->ro
== 0) {
2621 freeze_array(conf
, 1);
2622 fix_read_error(conf
, mddev
, r10_bio
);
2623 unfreeze_array(conf
);
2625 r10_bio
->devs
[slot
].bio
= IO_BLOCKED
;
2627 rdev_dec_pending(rdev
, mddev
);
2630 rdev
= read_balance(conf
, r10_bio
, &max_sectors
);
2632 printk(KERN_ALERT
"md/raid10:%s: %s: unrecoverable I/O"
2633 " read error for block %llu\n",
2635 (unsigned long long)r10_bio
->sector
);
2636 raid_end_bio_io(r10_bio
);
2640 do_sync
= (r10_bio
->master_bio
->bi_rw
& REQ_SYNC
);
2641 slot
= r10_bio
->read_slot
;
2644 "md/raid10:%s: %s: redirecting "
2645 "sector %llu to another mirror\n",
2647 bdevname(rdev
->bdev
, b
),
2648 (unsigned long long)r10_bio
->sector
);
2649 bio
= bio_clone_mddev(r10_bio
->master_bio
,
2651 bio_trim(bio
, r10_bio
->sector
- bio
->bi_iter
.bi_sector
, max_sectors
);
2652 r10_bio
->devs
[slot
].bio
= bio
;
2653 r10_bio
->devs
[slot
].rdev
= rdev
;
2654 bio
->bi_iter
.bi_sector
= r10_bio
->devs
[slot
].addr
2655 + choose_data_offset(r10_bio
, rdev
);
2656 bio
->bi_bdev
= rdev
->bdev
;
2657 bio
->bi_rw
= READ
| do_sync
;
2658 bio
->bi_private
= r10_bio
;
2659 bio
->bi_end_io
= raid10_end_read_request
;
2660 if (max_sectors
< r10_bio
->sectors
) {
2661 /* Drat - have to split this up more */
2662 struct bio
*mbio
= r10_bio
->master_bio
;
2663 int sectors_handled
=
2664 r10_bio
->sector
+ max_sectors
2665 - mbio
->bi_iter
.bi_sector
;
2666 r10_bio
->sectors
= max_sectors
;
2667 spin_lock_irq(&conf
->device_lock
);
2668 if (mbio
->bi_phys_segments
== 0)
2669 mbio
->bi_phys_segments
= 2;
2671 mbio
->bi_phys_segments
++;
2672 spin_unlock_irq(&conf
->device_lock
);
2673 generic_make_request(bio
);
2675 r10_bio
= mempool_alloc(conf
->r10bio_pool
,
2677 r10_bio
->master_bio
= mbio
;
2678 r10_bio
->sectors
= bio_sectors(mbio
) - sectors_handled
;
2680 set_bit(R10BIO_ReadError
,
2682 r10_bio
->mddev
= mddev
;
2683 r10_bio
->sector
= mbio
->bi_iter
.bi_sector
2688 generic_make_request(bio
);
2691 static void handle_write_completed(struct r10conf
*conf
, struct r10bio
*r10_bio
)
2693 /* Some sort of write request has finished and it
2694 * succeeded in writing where we thought there was a
2695 * bad block. So forget the bad block.
2696 * Or possibly if failed and we need to record
2700 struct md_rdev
*rdev
;
2702 if (test_bit(R10BIO_IsSync
, &r10_bio
->state
) ||
2703 test_bit(R10BIO_IsRecover
, &r10_bio
->state
)) {
2704 for (m
= 0; m
< conf
->copies
; m
++) {
2705 int dev
= r10_bio
->devs
[m
].devnum
;
2706 rdev
= conf
->mirrors
[dev
].rdev
;
2707 if (r10_bio
->devs
[m
].bio
== NULL
)
2709 if (test_bit(BIO_UPTODATE
,
2710 &r10_bio
->devs
[m
].bio
->bi_flags
)) {
2711 rdev_clear_badblocks(
2713 r10_bio
->devs
[m
].addr
,
2714 r10_bio
->sectors
, 0);
2716 if (!rdev_set_badblocks(
2718 r10_bio
->devs
[m
].addr
,
2719 r10_bio
->sectors
, 0))
2720 md_error(conf
->mddev
, rdev
);
2722 rdev
= conf
->mirrors
[dev
].replacement
;
2723 if (r10_bio
->devs
[m
].repl_bio
== NULL
)
2725 if (test_bit(BIO_UPTODATE
,
2726 &r10_bio
->devs
[m
].repl_bio
->bi_flags
)) {
2727 rdev_clear_badblocks(
2729 r10_bio
->devs
[m
].addr
,
2730 r10_bio
->sectors
, 0);
2732 if (!rdev_set_badblocks(
2734 r10_bio
->devs
[m
].addr
,
2735 r10_bio
->sectors
, 0))
2736 md_error(conf
->mddev
, rdev
);
2741 for (m
= 0; m
< conf
->copies
; m
++) {
2742 int dev
= r10_bio
->devs
[m
].devnum
;
2743 struct bio
*bio
= r10_bio
->devs
[m
].bio
;
2744 rdev
= conf
->mirrors
[dev
].rdev
;
2745 if (bio
== IO_MADE_GOOD
) {
2746 rdev_clear_badblocks(
2748 r10_bio
->devs
[m
].addr
,
2749 r10_bio
->sectors
, 0);
2750 rdev_dec_pending(rdev
, conf
->mddev
);
2751 } else if (bio
!= NULL
&&
2752 !test_bit(BIO_UPTODATE
, &bio
->bi_flags
)) {
2753 if (!narrow_write_error(r10_bio
, m
)) {
2754 md_error(conf
->mddev
, rdev
);
2755 set_bit(R10BIO_Degraded
,
2758 rdev_dec_pending(rdev
, conf
->mddev
);
2760 bio
= r10_bio
->devs
[m
].repl_bio
;
2761 rdev
= conf
->mirrors
[dev
].replacement
;
2762 if (rdev
&& bio
== IO_MADE_GOOD
) {
2763 rdev_clear_badblocks(
2765 r10_bio
->devs
[m
].addr
,
2766 r10_bio
->sectors
, 0);
2767 rdev_dec_pending(rdev
, conf
->mddev
);
2770 if (test_bit(R10BIO_WriteError
,
2772 close_write(r10_bio
);
2773 raid_end_bio_io(r10_bio
);
2777 static void raid10d(struct md_thread
*thread
)
2779 struct mddev
*mddev
= thread
->mddev
;
2780 struct r10bio
*r10_bio
;
2781 unsigned long flags
;
2782 struct r10conf
*conf
= mddev
->private;
2783 struct list_head
*head
= &conf
->retry_list
;
2784 struct blk_plug plug
;
2786 md_check_recovery(mddev
);
2788 blk_start_plug(&plug
);
2791 flush_pending_writes(conf
);
2793 spin_lock_irqsave(&conf
->device_lock
, flags
);
2794 if (list_empty(head
)) {
2795 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
2798 r10_bio
= list_entry(head
->prev
, struct r10bio
, retry_list
);
2799 list_del(head
->prev
);
2801 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
2803 mddev
= r10_bio
->mddev
;
2804 conf
= mddev
->private;
2805 if (test_bit(R10BIO_MadeGood
, &r10_bio
->state
) ||
2806 test_bit(R10BIO_WriteError
, &r10_bio
->state
))
2807 handle_write_completed(conf
, r10_bio
);
2808 else if (test_bit(R10BIO_IsReshape
, &r10_bio
->state
))
2809 reshape_request_write(mddev
, r10_bio
);
2810 else if (test_bit(R10BIO_IsSync
, &r10_bio
->state
))
2811 sync_request_write(mddev
, r10_bio
);
2812 else if (test_bit(R10BIO_IsRecover
, &r10_bio
->state
))
2813 recovery_request_write(mddev
, r10_bio
);
2814 else if (test_bit(R10BIO_ReadError
, &r10_bio
->state
))
2815 handle_read_error(mddev
, r10_bio
);
2817 /* just a partial read to be scheduled from a
2820 int slot
= r10_bio
->read_slot
;
2821 generic_make_request(r10_bio
->devs
[slot
].bio
);
2825 if (mddev
->flags
& ~(1<<MD_CHANGE_PENDING
))
2826 md_check_recovery(mddev
);
2828 blk_finish_plug(&plug
);
2831 static int init_resync(struct r10conf
*conf
)
2836 buffs
= RESYNC_WINDOW
/ RESYNC_BLOCK_SIZE
;
2837 BUG_ON(conf
->r10buf_pool
);
2838 conf
->have_replacement
= 0;
2839 for (i
= 0; i
< conf
->geo
.raid_disks
; i
++)
2840 if (conf
->mirrors
[i
].replacement
)
2841 conf
->have_replacement
= 1;
2842 conf
->r10buf_pool
= mempool_create(buffs
, r10buf_pool_alloc
, r10buf_pool_free
, conf
);
2843 if (!conf
->r10buf_pool
)
2845 conf
->next_resync
= 0;
2850 * perform a "sync" on one "block"
2852 * We need to make sure that no normal I/O request - particularly write
2853 * requests - conflict with active sync requests.
2855 * This is achieved by tracking pending requests and a 'barrier' concept
2856 * that can be installed to exclude normal IO requests.
2858 * Resync and recovery are handled very differently.
2859 * We differentiate by looking at MD_RECOVERY_SYNC in mddev->recovery.
2861 * For resync, we iterate over virtual addresses, read all copies,
2862 * and update if there are differences. If only one copy is live,
2864 * For recovery, we iterate over physical addresses, read a good
2865 * value for each non-in_sync drive, and over-write.
2867 * So, for recovery we may have several outstanding complex requests for a
2868 * given address, one for each out-of-sync device. We model this by allocating
2869 * a number of r10_bio structures, one for each out-of-sync device.
2870 * As we setup these structures, we collect all bio's together into a list
2871 * which we then process collectively to add pages, and then process again
2872 * to pass to generic_make_request.
2874 * The r10_bio structures are linked using a borrowed master_bio pointer.
2875 * This link is counted in ->remaining. When the r10_bio that points to NULL
2876 * has its remaining count decremented to 0, the whole complex operation
2881 static sector_t
sync_request(struct mddev
*mddev
, sector_t sector_nr
,
2884 struct r10conf
*conf
= mddev
->private;
2885 struct r10bio
*r10_bio
;
2886 struct bio
*biolist
= NULL
, *bio
;
2887 sector_t max_sector
, nr_sectors
;
2890 sector_t sync_blocks
;
2891 sector_t sectors_skipped
= 0;
2892 int chunks_skipped
= 0;
2893 sector_t chunk_mask
= conf
->geo
.chunk_mask
;
2895 if (!conf
->r10buf_pool
)
2896 if (init_resync(conf
))
2900 * Allow skipping a full rebuild for incremental assembly
2901 * of a clean array, like RAID1 does.
2903 if (mddev
->bitmap
== NULL
&&
2904 mddev
->recovery_cp
== MaxSector
&&
2905 mddev
->reshape_position
== MaxSector
&&
2906 !test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
) &&
2907 !test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
) &&
2908 !test_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
) &&
2909 conf
->fullsync
== 0) {
2911 return mddev
->dev_sectors
- sector_nr
;
2915 max_sector
= mddev
->dev_sectors
;
2916 if (test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
) ||
2917 test_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
))
2918 max_sector
= mddev
->resync_max_sectors
;
2919 if (sector_nr
>= max_sector
) {
2920 /* If we aborted, we need to abort the
2921 * sync on the 'current' bitmap chucks (there can
2922 * be several when recovering multiple devices).
2923 * as we may have started syncing it but not finished.
2924 * We can find the current address in
2925 * mddev->curr_resync, but for recovery,
2926 * we need to convert that to several
2927 * virtual addresses.
2929 if (test_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
)) {
2935 if (mddev
->curr_resync
< max_sector
) { /* aborted */
2936 if (test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
))
2937 bitmap_end_sync(mddev
->bitmap
, mddev
->curr_resync
,
2939 else for (i
= 0; i
< conf
->geo
.raid_disks
; i
++) {
2941 raid10_find_virt(conf
, mddev
->curr_resync
, i
);
2942 bitmap_end_sync(mddev
->bitmap
, sect
,
2946 /* completed sync */
2947 if ((!mddev
->bitmap
|| conf
->fullsync
)
2948 && conf
->have_replacement
2949 && test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
)) {
2950 /* Completed a full sync so the replacements
2951 * are now fully recovered.
2953 for (i
= 0; i
< conf
->geo
.raid_disks
; i
++)
2954 if (conf
->mirrors
[i
].replacement
)
2955 conf
->mirrors
[i
].replacement
2961 bitmap_close_sync(mddev
->bitmap
);
2964 return sectors_skipped
;
2967 if (test_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
))
2968 return reshape_request(mddev
, sector_nr
, skipped
);
2970 if (chunks_skipped
>= conf
->geo
.raid_disks
) {
2971 /* if there has been nothing to do on any drive,
2972 * then there is nothing to do at all..
2975 return (max_sector
- sector_nr
) + sectors_skipped
;
2978 if (max_sector
> mddev
->resync_max
)
2979 max_sector
= mddev
->resync_max
; /* Don't do IO beyond here */
2981 /* make sure whole request will fit in a chunk - if chunks
2984 if (conf
->geo
.near_copies
< conf
->geo
.raid_disks
&&
2985 max_sector
> (sector_nr
| chunk_mask
))
2986 max_sector
= (sector_nr
| chunk_mask
) + 1;
2988 /* Again, very different code for resync and recovery.
2989 * Both must result in an r10bio with a list of bios that
2990 * have bi_end_io, bi_sector, bi_bdev set,
2991 * and bi_private set to the r10bio.
2992 * For recovery, we may actually create several r10bios
2993 * with 2 bios in each, that correspond to the bios in the main one.
2994 * In this case, the subordinate r10bios link back through a
2995 * borrowed master_bio pointer, and the counter in the master
2996 * includes a ref from each subordinate.
2998 /* First, we decide what to do and set ->bi_end_io
2999 * To end_sync_read if we want to read, and
3000 * end_sync_write if we will want to write.
3003 max_sync
= RESYNC_PAGES
<< (PAGE_SHIFT
-9);
3004 if (!test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
)) {
3005 /* recovery... the complicated one */
3009 for (i
= 0 ; i
< conf
->geo
.raid_disks
; i
++) {
3015 struct raid10_info
*mirror
= &conf
->mirrors
[i
];
3017 if ((mirror
->rdev
== NULL
||
3018 test_bit(In_sync
, &mirror
->rdev
->flags
))
3020 (mirror
->replacement
== NULL
||
3022 &mirror
->replacement
->flags
)))
3026 /* want to reconstruct this device */
3028 sect
= raid10_find_virt(conf
, sector_nr
, i
);
3029 if (sect
>= mddev
->resync_max_sectors
) {
3030 /* last stripe is not complete - don't
3031 * try to recover this sector.
3035 /* Unless we are doing a full sync, or a replacement
3036 * we only need to recover the block if it is set in
3039 must_sync
= bitmap_start_sync(mddev
->bitmap
, sect
,
3041 if (sync_blocks
< max_sync
)
3042 max_sync
= sync_blocks
;
3044 mirror
->replacement
== NULL
&&
3046 /* yep, skip the sync_blocks here, but don't assume
3047 * that there will never be anything to do here
3049 chunks_skipped
= -1;
3053 r10_bio
= mempool_alloc(conf
->r10buf_pool
, GFP_NOIO
);
3055 raise_barrier(conf
, rb2
!= NULL
);
3056 atomic_set(&r10_bio
->remaining
, 0);
3058 r10_bio
->master_bio
= (struct bio
*)rb2
;
3060 atomic_inc(&rb2
->remaining
);
3061 r10_bio
->mddev
= mddev
;
3062 set_bit(R10BIO_IsRecover
, &r10_bio
->state
);
3063 r10_bio
->sector
= sect
;
3065 raid10_find_phys(conf
, r10_bio
);
3067 /* Need to check if the array will still be
3070 for (j
= 0; j
< conf
->geo
.raid_disks
; j
++)
3071 if (conf
->mirrors
[j
].rdev
== NULL
||
3072 test_bit(Faulty
, &conf
->mirrors
[j
].rdev
->flags
)) {
3077 must_sync
= bitmap_start_sync(mddev
->bitmap
, sect
,
3078 &sync_blocks
, still_degraded
);
3081 for (j
=0; j
<conf
->copies
;j
++) {
3083 int d
= r10_bio
->devs
[j
].devnum
;
3084 sector_t from_addr
, to_addr
;
3085 struct md_rdev
*rdev
;
3086 sector_t sector
, first_bad
;
3088 if (!conf
->mirrors
[d
].rdev
||
3089 !test_bit(In_sync
, &conf
->mirrors
[d
].rdev
->flags
))
3091 /* This is where we read from */
3093 rdev
= conf
->mirrors
[d
].rdev
;
3094 sector
= r10_bio
->devs
[j
].addr
;
3096 if (is_badblock(rdev
, sector
, max_sync
,
3097 &first_bad
, &bad_sectors
)) {
3098 if (first_bad
> sector
)
3099 max_sync
= first_bad
- sector
;
3101 bad_sectors
-= (sector
3103 if (max_sync
> bad_sectors
)
3104 max_sync
= bad_sectors
;
3108 bio
= r10_bio
->devs
[0].bio
;
3110 bio
->bi_next
= biolist
;
3112 bio
->bi_private
= r10_bio
;
3113 bio
->bi_end_io
= end_sync_read
;
3115 from_addr
= r10_bio
->devs
[j
].addr
;
3116 bio
->bi_iter
.bi_sector
= from_addr
+
3118 bio
->bi_bdev
= rdev
->bdev
;
3119 atomic_inc(&rdev
->nr_pending
);
3120 /* and we write to 'i' (if not in_sync) */
3122 for (k
=0; k
<conf
->copies
; k
++)
3123 if (r10_bio
->devs
[k
].devnum
== i
)
3125 BUG_ON(k
== conf
->copies
);
3126 to_addr
= r10_bio
->devs
[k
].addr
;
3127 r10_bio
->devs
[0].devnum
= d
;
3128 r10_bio
->devs
[0].addr
= from_addr
;
3129 r10_bio
->devs
[1].devnum
= i
;
3130 r10_bio
->devs
[1].addr
= to_addr
;
3132 rdev
= mirror
->rdev
;
3133 if (!test_bit(In_sync
, &rdev
->flags
)) {
3134 bio
= r10_bio
->devs
[1].bio
;
3136 bio
->bi_next
= biolist
;
3138 bio
->bi_private
= r10_bio
;
3139 bio
->bi_end_io
= end_sync_write
;
3141 bio
->bi_iter
.bi_sector
= to_addr
3142 + rdev
->data_offset
;
3143 bio
->bi_bdev
= rdev
->bdev
;
3144 atomic_inc(&r10_bio
->remaining
);
3146 r10_bio
->devs
[1].bio
->bi_end_io
= NULL
;
3148 /* and maybe write to replacement */
3149 bio
= r10_bio
->devs
[1].repl_bio
;
3151 bio
->bi_end_io
= NULL
;
3152 rdev
= mirror
->replacement
;
3153 /* Note: if rdev != NULL, then bio
3154 * cannot be NULL as r10buf_pool_alloc will
3155 * have allocated it.
3156 * So the second test here is pointless.
3157 * But it keeps semantic-checkers happy, and
3158 * this comment keeps human reviewers
3161 if (rdev
== NULL
|| bio
== NULL
||
3162 test_bit(Faulty
, &rdev
->flags
))
3165 bio
->bi_next
= biolist
;
3167 bio
->bi_private
= r10_bio
;
3168 bio
->bi_end_io
= end_sync_write
;
3170 bio
->bi_iter
.bi_sector
= to_addr
+
3172 bio
->bi_bdev
= rdev
->bdev
;
3173 atomic_inc(&r10_bio
->remaining
);
3176 if (j
== conf
->copies
) {
3177 /* Cannot recover, so abort the recovery or
3178 * record a bad block */
3180 /* problem is that there are bad blocks
3181 * on other device(s)
3184 for (k
= 0; k
< conf
->copies
; k
++)
3185 if (r10_bio
->devs
[k
].devnum
== i
)
3187 if (!test_bit(In_sync
,
3188 &mirror
->rdev
->flags
)
3189 && !rdev_set_badblocks(
3191 r10_bio
->devs
[k
].addr
,
3194 if (mirror
->replacement
&&
3195 !rdev_set_badblocks(
3196 mirror
->replacement
,
3197 r10_bio
->devs
[k
].addr
,
3202 if (!test_and_set_bit(MD_RECOVERY_INTR
,
3204 printk(KERN_INFO
"md/raid10:%s: insufficient "
3205 "working devices for recovery.\n",
3207 mirror
->recovery_disabled
3208 = mddev
->recovery_disabled
;
3212 atomic_dec(&rb2
->remaining
);
3217 if (biolist
== NULL
) {
3219 struct r10bio
*rb2
= r10_bio
;
3220 r10_bio
= (struct r10bio
*) rb2
->master_bio
;
3221 rb2
->master_bio
= NULL
;
3227 /* resync. Schedule a read for every block at this virt offset */
3230 bitmap_cond_end_sync(mddev
->bitmap
, sector_nr
);
3232 if (!bitmap_start_sync(mddev
->bitmap
, sector_nr
,
3233 &sync_blocks
, mddev
->degraded
) &&
3234 !conf
->fullsync
&& !test_bit(MD_RECOVERY_REQUESTED
,
3235 &mddev
->recovery
)) {
3236 /* We can skip this block */
3238 return sync_blocks
+ sectors_skipped
;
3240 if (sync_blocks
< max_sync
)
3241 max_sync
= sync_blocks
;
3242 r10_bio
= mempool_alloc(conf
->r10buf_pool
, GFP_NOIO
);
3245 r10_bio
->mddev
= mddev
;
3246 atomic_set(&r10_bio
->remaining
, 0);
3247 raise_barrier(conf
, 0);
3248 conf
->next_resync
= sector_nr
;
3250 r10_bio
->master_bio
= NULL
;
3251 r10_bio
->sector
= sector_nr
;
3252 set_bit(R10BIO_IsSync
, &r10_bio
->state
);
3253 raid10_find_phys(conf
, r10_bio
);
3254 r10_bio
->sectors
= (sector_nr
| chunk_mask
) - sector_nr
+ 1;
3256 for (i
= 0; i
< conf
->copies
; i
++) {
3257 int d
= r10_bio
->devs
[i
].devnum
;
3258 sector_t first_bad
, sector
;
3261 if (r10_bio
->devs
[i
].repl_bio
)
3262 r10_bio
->devs
[i
].repl_bio
->bi_end_io
= NULL
;
3264 bio
= r10_bio
->devs
[i
].bio
;
3266 clear_bit(BIO_UPTODATE
, &bio
->bi_flags
);
3267 if (conf
->mirrors
[d
].rdev
== NULL
||
3268 test_bit(Faulty
, &conf
->mirrors
[d
].rdev
->flags
))
3270 sector
= r10_bio
->devs
[i
].addr
;
3271 if (is_badblock(conf
->mirrors
[d
].rdev
,
3273 &first_bad
, &bad_sectors
)) {
3274 if (first_bad
> sector
)
3275 max_sync
= first_bad
- sector
;
3277 bad_sectors
-= (sector
- first_bad
);
3278 if (max_sync
> bad_sectors
)
3279 max_sync
= bad_sectors
;
3283 atomic_inc(&conf
->mirrors
[d
].rdev
->nr_pending
);
3284 atomic_inc(&r10_bio
->remaining
);
3285 bio
->bi_next
= biolist
;
3287 bio
->bi_private
= r10_bio
;
3288 bio
->bi_end_io
= end_sync_read
;
3290 bio
->bi_iter
.bi_sector
= sector
+
3291 conf
->mirrors
[d
].rdev
->data_offset
;
3292 bio
->bi_bdev
= conf
->mirrors
[d
].rdev
->bdev
;
3295 if (conf
->mirrors
[d
].replacement
== NULL
||
3297 &conf
->mirrors
[d
].replacement
->flags
))
3300 /* Need to set up for writing to the replacement */
3301 bio
= r10_bio
->devs
[i
].repl_bio
;
3303 clear_bit(BIO_UPTODATE
, &bio
->bi_flags
);
3305 sector
= r10_bio
->devs
[i
].addr
;
3306 atomic_inc(&conf
->mirrors
[d
].rdev
->nr_pending
);
3307 bio
->bi_next
= biolist
;
3309 bio
->bi_private
= r10_bio
;
3310 bio
->bi_end_io
= end_sync_write
;
3312 bio
->bi_iter
.bi_sector
= sector
+
3313 conf
->mirrors
[d
].replacement
->data_offset
;
3314 bio
->bi_bdev
= conf
->mirrors
[d
].replacement
->bdev
;
3319 for (i
=0; i
<conf
->copies
; i
++) {
3320 int d
= r10_bio
->devs
[i
].devnum
;
3321 if (r10_bio
->devs
[i
].bio
->bi_end_io
)
3322 rdev_dec_pending(conf
->mirrors
[d
].rdev
,
3324 if (r10_bio
->devs
[i
].repl_bio
&&
3325 r10_bio
->devs
[i
].repl_bio
->bi_end_io
)
3327 conf
->mirrors
[d
].replacement
,
3337 if (sector_nr
+ max_sync
< max_sector
)
3338 max_sector
= sector_nr
+ max_sync
;
3341 int len
= PAGE_SIZE
;
3342 if (sector_nr
+ (len
>>9) > max_sector
)
3343 len
= (max_sector
- sector_nr
) << 9;
3346 for (bio
= biolist
; bio
; bio
=bio
->bi_next
) {
3348 page
= bio
->bi_io_vec
[bio
->bi_vcnt
].bv_page
;
3349 if (bio_add_page(bio
, page
, len
, 0))
3353 bio
->bi_io_vec
[bio
->bi_vcnt
].bv_page
= page
;
3354 for (bio2
= biolist
;
3355 bio2
&& bio2
!= bio
;
3356 bio2
= bio2
->bi_next
) {
3357 /* remove last page from this bio */
3359 bio2
->bi_iter
.bi_size
-= len
;
3360 __clear_bit(BIO_SEG_VALID
, &bio2
->bi_flags
);
3364 nr_sectors
+= len
>>9;
3365 sector_nr
+= len
>>9;
3366 } while (biolist
->bi_vcnt
< RESYNC_PAGES
);
3368 r10_bio
->sectors
= nr_sectors
;
3372 biolist
= biolist
->bi_next
;
3374 bio
->bi_next
= NULL
;
3375 r10_bio
= bio
->bi_private
;
3376 r10_bio
->sectors
= nr_sectors
;
3378 if (bio
->bi_end_io
== end_sync_read
) {
3379 md_sync_acct(bio
->bi_bdev
, nr_sectors
);
3380 set_bit(BIO_UPTODATE
, &bio
->bi_flags
);
3381 generic_make_request(bio
);
3385 if (sectors_skipped
)
3386 /* pretend they weren't skipped, it makes
3387 * no important difference in this case
3389 md_done_sync(mddev
, sectors_skipped
, 1);
3391 return sectors_skipped
+ nr_sectors
;
3393 /* There is nowhere to write, so all non-sync
3394 * drives must be failed or in resync, all drives
3395 * have a bad block, so try the next chunk...
3397 if (sector_nr
+ max_sync
< max_sector
)
3398 max_sector
= sector_nr
+ max_sync
;
3400 sectors_skipped
+= (max_sector
- sector_nr
);
3402 sector_nr
= max_sector
;
3407 raid10_size(struct mddev
*mddev
, sector_t sectors
, int raid_disks
)
3410 struct r10conf
*conf
= mddev
->private;
3413 raid_disks
= min(conf
->geo
.raid_disks
,
3414 conf
->prev
.raid_disks
);
3416 sectors
= conf
->dev_sectors
;
3418 size
= sectors
>> conf
->geo
.chunk_shift
;
3419 sector_div(size
, conf
->geo
.far_copies
);
3420 size
= size
* raid_disks
;
3421 sector_div(size
, conf
->geo
.near_copies
);
3423 return size
<< conf
->geo
.chunk_shift
;
3426 static void calc_sectors(struct r10conf
*conf
, sector_t size
)
3428 /* Calculate the number of sectors-per-device that will
3429 * actually be used, and set conf->dev_sectors and
3433 size
= size
>> conf
->geo
.chunk_shift
;
3434 sector_div(size
, conf
->geo
.far_copies
);
3435 size
= size
* conf
->geo
.raid_disks
;
3436 sector_div(size
, conf
->geo
.near_copies
);
3437 /* 'size' is now the number of chunks in the array */
3438 /* calculate "used chunks per device" */
3439 size
= size
* conf
->copies
;
3441 /* We need to round up when dividing by raid_disks to
3442 * get the stride size.
3444 size
= DIV_ROUND_UP_SECTOR_T(size
, conf
->geo
.raid_disks
);
3446 conf
->dev_sectors
= size
<< conf
->geo
.chunk_shift
;
3448 if (conf
->geo
.far_offset
)
3449 conf
->geo
.stride
= 1 << conf
->geo
.chunk_shift
;
3451 sector_div(size
, conf
->geo
.far_copies
);
3452 conf
->geo
.stride
= size
<< conf
->geo
.chunk_shift
;
3456 enum geo_type
{geo_new
, geo_old
, geo_start
};
3457 static int setup_geo(struct geom
*geo
, struct mddev
*mddev
, enum geo_type
new)
3460 int layout
, chunk
, disks
;
3463 layout
= mddev
->layout
;
3464 chunk
= mddev
->chunk_sectors
;
3465 disks
= mddev
->raid_disks
- mddev
->delta_disks
;
3468 layout
= mddev
->new_layout
;
3469 chunk
= mddev
->new_chunk_sectors
;
3470 disks
= mddev
->raid_disks
;
3472 default: /* avoid 'may be unused' warnings */
3473 case geo_start
: /* new when starting reshape - raid_disks not
3475 layout
= mddev
->new_layout
;
3476 chunk
= mddev
->new_chunk_sectors
;
3477 disks
= mddev
->raid_disks
+ mddev
->delta_disks
;
3482 if (chunk
< (PAGE_SIZE
>> 9) ||
3483 !is_power_of_2(chunk
))
3486 fc
= (layout
>> 8) & 255;
3487 fo
= layout
& (1<<16);
3488 geo
->raid_disks
= disks
;
3489 geo
->near_copies
= nc
;
3490 geo
->far_copies
= fc
;
3491 geo
->far_offset
= fo
;
3492 geo
->far_set_size
= (layout
& (1<<17)) ? disks
/ fc
: disks
;
3493 geo
->chunk_mask
= chunk
- 1;
3494 geo
->chunk_shift
= ffz(~chunk
);
3498 static struct r10conf
*setup_conf(struct mddev
*mddev
)
3500 struct r10conf
*conf
= NULL
;
3505 copies
= setup_geo(&geo
, mddev
, geo_new
);
3508 printk(KERN_ERR
"md/raid10:%s: chunk size must be "
3509 "at least PAGE_SIZE(%ld) and be a power of 2.\n",
3510 mdname(mddev
), PAGE_SIZE
);
3514 if (copies
< 2 || copies
> mddev
->raid_disks
) {
3515 printk(KERN_ERR
"md/raid10:%s: unsupported raid10 layout: 0x%8x\n",
3516 mdname(mddev
), mddev
->new_layout
);
3521 conf
= kzalloc(sizeof(struct r10conf
), GFP_KERNEL
);
3525 /* FIXME calc properly */
3526 conf
->mirrors
= kzalloc(sizeof(struct raid10_info
)*(mddev
->raid_disks
+
3527 max(0,-mddev
->delta_disks
)),
3532 conf
->tmppage
= alloc_page(GFP_KERNEL
);
3537 conf
->copies
= copies
;
3538 conf
->r10bio_pool
= mempool_create(NR_RAID10_BIOS
, r10bio_pool_alloc
,
3539 r10bio_pool_free
, conf
);
3540 if (!conf
->r10bio_pool
)
3543 calc_sectors(conf
, mddev
->dev_sectors
);
3544 if (mddev
->reshape_position
== MaxSector
) {
3545 conf
->prev
= conf
->geo
;
3546 conf
->reshape_progress
= MaxSector
;
3548 if (setup_geo(&conf
->prev
, mddev
, geo_old
) != conf
->copies
) {
3552 conf
->reshape_progress
= mddev
->reshape_position
;
3553 if (conf
->prev
.far_offset
)
3554 conf
->prev
.stride
= 1 << conf
->prev
.chunk_shift
;
3556 /* far_copies must be 1 */
3557 conf
->prev
.stride
= conf
->dev_sectors
;
3559 conf
->reshape_safe
= conf
->reshape_progress
;
3560 spin_lock_init(&conf
->device_lock
);
3561 INIT_LIST_HEAD(&conf
->retry_list
);
3563 spin_lock_init(&conf
->resync_lock
);
3564 init_waitqueue_head(&conf
->wait_barrier
);
3566 conf
->thread
= md_register_thread(raid10d
, mddev
, "raid10");
3570 conf
->mddev
= mddev
;
3575 printk(KERN_ERR
"md/raid10:%s: couldn't allocate memory.\n",
3578 if (conf
->r10bio_pool
)
3579 mempool_destroy(conf
->r10bio_pool
);
3580 kfree(conf
->mirrors
);
3581 safe_put_page(conf
->tmppage
);
3584 return ERR_PTR(err
);
3587 static int run(struct mddev
*mddev
)
3589 struct r10conf
*conf
;
3590 int i
, disk_idx
, chunk_size
;
3591 struct raid10_info
*disk
;
3592 struct md_rdev
*rdev
;
3594 sector_t min_offset_diff
= 0;
3596 bool discard_supported
= false;
3598 if (mddev
->private == NULL
) {
3599 conf
= setup_conf(mddev
);
3601 return PTR_ERR(conf
);
3602 mddev
->private = conf
;
3604 conf
= mddev
->private;
3608 mddev
->thread
= conf
->thread
;
3609 conf
->thread
= NULL
;
3611 chunk_size
= mddev
->chunk_sectors
<< 9;
3613 blk_queue_max_discard_sectors(mddev
->queue
,
3614 mddev
->chunk_sectors
);
3615 blk_queue_max_write_same_sectors(mddev
->queue
, 0);
3616 blk_queue_io_min(mddev
->queue
, chunk_size
);
3617 if (conf
->geo
.raid_disks
% conf
->geo
.near_copies
)
3618 blk_queue_io_opt(mddev
->queue
, chunk_size
* conf
->geo
.raid_disks
);
3620 blk_queue_io_opt(mddev
->queue
, chunk_size
*
3621 (conf
->geo
.raid_disks
/ conf
->geo
.near_copies
));
3624 rdev_for_each(rdev
, mddev
) {
3626 struct request_queue
*q
;
3628 disk_idx
= rdev
->raid_disk
;
3631 if (disk_idx
>= conf
->geo
.raid_disks
&&
3632 disk_idx
>= conf
->prev
.raid_disks
)
3634 disk
= conf
->mirrors
+ disk_idx
;
3636 if (test_bit(Replacement
, &rdev
->flags
)) {
3637 if (disk
->replacement
)
3639 disk
->replacement
= rdev
;
3645 q
= bdev_get_queue(rdev
->bdev
);
3646 if (q
->merge_bvec_fn
)
3647 mddev
->merge_check_needed
= 1;
3648 diff
= (rdev
->new_data_offset
- rdev
->data_offset
);
3649 if (!mddev
->reshape_backwards
)
3653 if (first
|| diff
< min_offset_diff
)
3654 min_offset_diff
= diff
;
3657 disk_stack_limits(mddev
->gendisk
, rdev
->bdev
,
3658 rdev
->data_offset
<< 9);
3660 disk
->head_position
= 0;
3662 if (blk_queue_discard(bdev_get_queue(rdev
->bdev
)))
3663 discard_supported
= true;
3667 if (discard_supported
)
3668 queue_flag_set_unlocked(QUEUE_FLAG_DISCARD
,
3671 queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD
,
3674 /* need to check that every block has at least one working mirror */
3675 if (!enough(conf
, -1)) {
3676 printk(KERN_ERR
"md/raid10:%s: not enough operational mirrors.\n",
3681 if (conf
->reshape_progress
!= MaxSector
) {
3682 /* must ensure that shape change is supported */
3683 if (conf
->geo
.far_copies
!= 1 &&
3684 conf
->geo
.far_offset
== 0)
3686 if (conf
->prev
.far_copies
!= 1 &&
3687 conf
->prev
.far_offset
== 0)
3691 mddev
->degraded
= 0;
3693 i
< conf
->geo
.raid_disks
3694 || i
< conf
->prev
.raid_disks
;
3697 disk
= conf
->mirrors
+ i
;
3699 if (!disk
->rdev
&& disk
->replacement
) {
3700 /* The replacement is all we have - use it */
3701 disk
->rdev
= disk
->replacement
;
3702 disk
->replacement
= NULL
;
3703 clear_bit(Replacement
, &disk
->rdev
->flags
);
3707 !test_bit(In_sync
, &disk
->rdev
->flags
)) {
3708 disk
->head_position
= 0;
3711 disk
->rdev
->saved_raid_disk
< 0)
3714 disk
->recovery_disabled
= mddev
->recovery_disabled
- 1;
3717 if (mddev
->recovery_cp
!= MaxSector
)
3718 printk(KERN_NOTICE
"md/raid10:%s: not clean"
3719 " -- starting background reconstruction\n",
3722 "md/raid10:%s: active with %d out of %d devices\n",
3723 mdname(mddev
), conf
->geo
.raid_disks
- mddev
->degraded
,
3724 conf
->geo
.raid_disks
);
3726 * Ok, everything is just fine now
3728 mddev
->dev_sectors
= conf
->dev_sectors
;
3729 size
= raid10_size(mddev
, 0, 0);
3730 md_set_array_sectors(mddev
, size
);
3731 mddev
->resync_max_sectors
= size
;
3734 int stripe
= conf
->geo
.raid_disks
*
3735 ((mddev
->chunk_sectors
<< 9) / PAGE_SIZE
);
3737 /* Calculate max read-ahead size.
3738 * We need to readahead at least twice a whole stripe....
3741 stripe
/= conf
->geo
.near_copies
;
3742 if (mddev
->queue
->backing_dev_info
.ra_pages
< 2 * stripe
)
3743 mddev
->queue
->backing_dev_info
.ra_pages
= 2 * stripe
;
3746 if (md_integrity_register(mddev
))
3749 if (conf
->reshape_progress
!= MaxSector
) {
3750 unsigned long before_length
, after_length
;
3752 before_length
= ((1 << conf
->prev
.chunk_shift
) *
3753 conf
->prev
.far_copies
);
3754 after_length
= ((1 << conf
->geo
.chunk_shift
) *
3755 conf
->geo
.far_copies
);
3757 if (max(before_length
, after_length
) > min_offset_diff
) {
3758 /* This cannot work */
3759 printk("md/raid10: offset difference not enough to continue reshape\n");
3762 conf
->offset_diff
= min_offset_diff
;
3764 clear_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
);
3765 clear_bit(MD_RECOVERY_CHECK
, &mddev
->recovery
);
3766 set_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
);
3767 set_bit(MD_RECOVERY_RUNNING
, &mddev
->recovery
);
3768 mddev
->sync_thread
= md_register_thread(md_do_sync
, mddev
,
3775 md_unregister_thread(&mddev
->thread
);
3776 if (conf
->r10bio_pool
)
3777 mempool_destroy(conf
->r10bio_pool
);
3778 safe_put_page(conf
->tmppage
);
3779 kfree(conf
->mirrors
);
3781 mddev
->private = NULL
;
3786 static void raid10_free(struct mddev
*mddev
, void *priv
)
3788 struct r10conf
*conf
= priv
;
3790 if (conf
->r10bio_pool
)
3791 mempool_destroy(conf
->r10bio_pool
);
3792 safe_put_page(conf
->tmppage
);
3793 kfree(conf
->mirrors
);
3794 kfree(conf
->mirrors_old
);
3795 kfree(conf
->mirrors_new
);
3799 static void raid10_quiesce(struct mddev
*mddev
, int state
)
3801 struct r10conf
*conf
= mddev
->private;
3805 raise_barrier(conf
, 0);
3808 lower_barrier(conf
);
3813 static int raid10_resize(struct mddev
*mddev
, sector_t sectors
)
3815 /* Resize of 'far' arrays is not supported.
3816 * For 'near' and 'offset' arrays we can set the
3817 * number of sectors used to be an appropriate multiple
3818 * of the chunk size.
3819 * For 'offset', this is far_copies*chunksize.
3820 * For 'near' the multiplier is the LCM of
3821 * near_copies and raid_disks.
3822 * So if far_copies > 1 && !far_offset, fail.
3823 * Else find LCM(raid_disks, near_copy)*far_copies and
3824 * multiply by chunk_size. Then round to this number.
3825 * This is mostly done by raid10_size()
3827 struct r10conf
*conf
= mddev
->private;
3828 sector_t oldsize
, size
;
3830 if (mddev
->reshape_position
!= MaxSector
)
3833 if (conf
->geo
.far_copies
> 1 && !conf
->geo
.far_offset
)
3836 oldsize
= raid10_size(mddev
, 0, 0);
3837 size
= raid10_size(mddev
, sectors
, 0);
3838 if (mddev
->external_size
&&
3839 mddev
->array_sectors
> size
)
3841 if (mddev
->bitmap
) {
3842 int ret
= bitmap_resize(mddev
->bitmap
, size
, 0, 0);
3846 md_set_array_sectors(mddev
, size
);
3847 set_capacity(mddev
->gendisk
, mddev
->array_sectors
);
3848 revalidate_disk(mddev
->gendisk
);
3849 if (sectors
> mddev
->dev_sectors
&&
3850 mddev
->recovery_cp
> oldsize
) {
3851 mddev
->recovery_cp
= oldsize
;
3852 set_bit(MD_RECOVERY_NEEDED
, &mddev
->recovery
);
3854 calc_sectors(conf
, sectors
);
3855 mddev
->dev_sectors
= conf
->dev_sectors
;
3856 mddev
->resync_max_sectors
= size
;
3860 static void *raid10_takeover_raid0(struct mddev
*mddev
, sector_t size
, int devs
)
3862 struct md_rdev
*rdev
;
3863 struct r10conf
*conf
;
3865 if (mddev
->degraded
> 0) {
3866 printk(KERN_ERR
"md/raid10:%s: Error: degraded raid0!\n",
3868 return ERR_PTR(-EINVAL
);
3870 sector_div(size
, devs
);
3872 /* Set new parameters */
3873 mddev
->new_level
= 10;
3874 /* new layout: far_copies = 1, near_copies = 2 */
3875 mddev
->new_layout
= (1<<8) + 2;
3876 mddev
->new_chunk_sectors
= mddev
->chunk_sectors
;
3877 mddev
->delta_disks
= mddev
->raid_disks
;
3878 mddev
->raid_disks
*= 2;
3879 /* make sure it will be not marked as dirty */
3880 mddev
->recovery_cp
= MaxSector
;
3881 mddev
->dev_sectors
= size
;
3883 conf
= setup_conf(mddev
);
3884 if (!IS_ERR(conf
)) {
3885 rdev_for_each(rdev
, mddev
)
3886 if (rdev
->raid_disk
>= 0) {
3887 rdev
->new_raid_disk
= rdev
->raid_disk
* 2;
3888 rdev
->sectors
= size
;
3896 static void *raid10_takeover(struct mddev
*mddev
)
3898 struct r0conf
*raid0_conf
;
3900 /* raid10 can take over:
3901 * raid0 - providing it has only two drives
3903 if (mddev
->level
== 0) {
3904 /* for raid0 takeover only one zone is supported */
3905 raid0_conf
= mddev
->private;
3906 if (raid0_conf
->nr_strip_zones
> 1) {
3907 printk(KERN_ERR
"md/raid10:%s: cannot takeover raid 0"
3908 " with more than one zone.\n",
3910 return ERR_PTR(-EINVAL
);
3912 return raid10_takeover_raid0(mddev
,
3913 raid0_conf
->strip_zone
->zone_end
,
3914 raid0_conf
->strip_zone
->nb_dev
);
3916 return ERR_PTR(-EINVAL
);
3919 static int raid10_check_reshape(struct mddev
*mddev
)
3921 /* Called when there is a request to change
3922 * - layout (to ->new_layout)
3923 * - chunk size (to ->new_chunk_sectors)
3924 * - raid_disks (by delta_disks)
3925 * or when trying to restart a reshape that was ongoing.
3927 * We need to validate the request and possibly allocate
3928 * space if that might be an issue later.
3930 * Currently we reject any reshape of a 'far' mode array,
3931 * allow chunk size to change if new is generally acceptable,
3932 * allow raid_disks to increase, and allow
3933 * a switch between 'near' mode and 'offset' mode.
3935 struct r10conf
*conf
= mddev
->private;
3938 if (conf
->geo
.far_copies
!= 1 && !conf
->geo
.far_offset
)
3941 if (setup_geo(&geo
, mddev
, geo_start
) != conf
->copies
)
3942 /* mustn't change number of copies */
3944 if (geo
.far_copies
> 1 && !geo
.far_offset
)
3945 /* Cannot switch to 'far' mode */
3948 if (mddev
->array_sectors
& geo
.chunk_mask
)
3949 /* not factor of array size */
3952 if (!enough(conf
, -1))
3955 kfree(conf
->mirrors_new
);
3956 conf
->mirrors_new
= NULL
;
3957 if (mddev
->delta_disks
> 0) {
3958 /* allocate new 'mirrors' list */
3959 conf
->mirrors_new
= kzalloc(
3960 sizeof(struct raid10_info
)
3961 *(mddev
->raid_disks
+
3962 mddev
->delta_disks
),
3964 if (!conf
->mirrors_new
)
3971 * Need to check if array has failed when deciding whether to:
3973 * - remove non-faulty devices
3976 * This determination is simple when no reshape is happening.
3977 * However if there is a reshape, we need to carefully check
3978 * both the before and after sections.
3979 * This is because some failed devices may only affect one
3980 * of the two sections, and some non-in_sync devices may
3981 * be insync in the section most affected by failed devices.
3983 static int calc_degraded(struct r10conf
*conf
)
3985 int degraded
, degraded2
;
3990 /* 'prev' section first */
3991 for (i
= 0; i
< conf
->prev
.raid_disks
; i
++) {
3992 struct md_rdev
*rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
3993 if (!rdev
|| test_bit(Faulty
, &rdev
->flags
))
3995 else if (!test_bit(In_sync
, &rdev
->flags
))
3996 /* When we can reduce the number of devices in
3997 * an array, this might not contribute to
3998 * 'degraded'. It does now.
4003 if (conf
->geo
.raid_disks
== conf
->prev
.raid_disks
)
4007 for (i
= 0; i
< conf
->geo
.raid_disks
; i
++) {
4008 struct md_rdev
*rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
4009 if (!rdev
|| test_bit(Faulty
, &rdev
->flags
))
4011 else if (!test_bit(In_sync
, &rdev
->flags
)) {
4012 /* If reshape is increasing the number of devices,
4013 * this section has already been recovered, so
4014 * it doesn't contribute to degraded.
4017 if (conf
->geo
.raid_disks
<= conf
->prev
.raid_disks
)
4022 if (degraded2
> degraded
)
4027 static int raid10_start_reshape(struct mddev
*mddev
)
4029 /* A 'reshape' has been requested. This commits
4030 * the various 'new' fields and sets MD_RECOVER_RESHAPE
4031 * This also checks if there are enough spares and adds them
4033 * We currently require enough spares to make the final
4034 * array non-degraded. We also require that the difference
4035 * between old and new data_offset - on each device - is
4036 * enough that we never risk over-writing.
4039 unsigned long before_length
, after_length
;
4040 sector_t min_offset_diff
= 0;
4043 struct r10conf
*conf
= mddev
->private;
4044 struct md_rdev
*rdev
;
4048 if (test_bit(MD_RECOVERY_RUNNING
, &mddev
->recovery
))
4051 if (setup_geo(&new, mddev
, geo_start
) != conf
->copies
)
4054 before_length
= ((1 << conf
->prev
.chunk_shift
) *
4055 conf
->prev
.far_copies
);
4056 after_length
= ((1 << conf
->geo
.chunk_shift
) *
4057 conf
->geo
.far_copies
);
4059 rdev_for_each(rdev
, mddev
) {
4060 if (!test_bit(In_sync
, &rdev
->flags
)
4061 && !test_bit(Faulty
, &rdev
->flags
))
4063 if (rdev
->raid_disk
>= 0) {
4064 long long diff
= (rdev
->new_data_offset
4065 - rdev
->data_offset
);
4066 if (!mddev
->reshape_backwards
)
4070 if (first
|| diff
< min_offset_diff
)
4071 min_offset_diff
= diff
;
4075 if (max(before_length
, after_length
) > min_offset_diff
)
4078 if (spares
< mddev
->delta_disks
)
4081 conf
->offset_diff
= min_offset_diff
;
4082 spin_lock_irq(&conf
->device_lock
);
4083 if (conf
->mirrors_new
) {
4084 memcpy(conf
->mirrors_new
, conf
->mirrors
,
4085 sizeof(struct raid10_info
)*conf
->prev
.raid_disks
);
4087 kfree(conf
->mirrors_old
);
4088 conf
->mirrors_old
= conf
->mirrors
;
4089 conf
->mirrors
= conf
->mirrors_new
;
4090 conf
->mirrors_new
= NULL
;
4092 setup_geo(&conf
->geo
, mddev
, geo_start
);
4094 if (mddev
->reshape_backwards
) {
4095 sector_t size
= raid10_size(mddev
, 0, 0);
4096 if (size
< mddev
->array_sectors
) {
4097 spin_unlock_irq(&conf
->device_lock
);
4098 printk(KERN_ERR
"md/raid10:%s: array size must be reduce before number of disks\n",
4102 mddev
->resync_max_sectors
= size
;
4103 conf
->reshape_progress
= size
;
4105 conf
->reshape_progress
= 0;
4106 conf
->reshape_safe
= conf
->reshape_progress
;
4107 spin_unlock_irq(&conf
->device_lock
);
4109 if (mddev
->delta_disks
&& mddev
->bitmap
) {
4110 ret
= bitmap_resize(mddev
->bitmap
,
4111 raid10_size(mddev
, 0,
4112 conf
->geo
.raid_disks
),
4117 if (mddev
->delta_disks
> 0) {
4118 rdev_for_each(rdev
, mddev
)
4119 if (rdev
->raid_disk
< 0 &&
4120 !test_bit(Faulty
, &rdev
->flags
)) {
4121 if (raid10_add_disk(mddev
, rdev
) == 0) {
4122 if (rdev
->raid_disk
>=
4123 conf
->prev
.raid_disks
)
4124 set_bit(In_sync
, &rdev
->flags
);
4126 rdev
->recovery_offset
= 0;
4128 if (sysfs_link_rdev(mddev
, rdev
))
4129 /* Failure here is OK */;
4131 } else if (rdev
->raid_disk
>= conf
->prev
.raid_disks
4132 && !test_bit(Faulty
, &rdev
->flags
)) {
4133 /* This is a spare that was manually added */
4134 set_bit(In_sync
, &rdev
->flags
);
4137 /* When a reshape changes the number of devices,
4138 * ->degraded is measured against the larger of the
4139 * pre and post numbers.
4141 spin_lock_irq(&conf
->device_lock
);
4142 mddev
->degraded
= calc_degraded(conf
);
4143 spin_unlock_irq(&conf
->device_lock
);
4144 mddev
->raid_disks
= conf
->geo
.raid_disks
;
4145 mddev
->reshape_position
= conf
->reshape_progress
;
4146 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
4148 clear_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
);
4149 clear_bit(MD_RECOVERY_CHECK
, &mddev
->recovery
);
4150 clear_bit(MD_RECOVERY_DONE
, &mddev
->recovery
);
4151 set_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
);
4152 set_bit(MD_RECOVERY_RUNNING
, &mddev
->recovery
);
4154 mddev
->sync_thread
= md_register_thread(md_do_sync
, mddev
,
4156 if (!mddev
->sync_thread
) {
4160 conf
->reshape_checkpoint
= jiffies
;
4161 md_wakeup_thread(mddev
->sync_thread
);
4162 md_new_event(mddev
);
4166 mddev
->recovery
= 0;
4167 spin_lock_irq(&conf
->device_lock
);
4168 conf
->geo
= conf
->prev
;
4169 mddev
->raid_disks
= conf
->geo
.raid_disks
;
4170 rdev_for_each(rdev
, mddev
)
4171 rdev
->new_data_offset
= rdev
->data_offset
;
4173 conf
->reshape_progress
= MaxSector
;
4174 conf
->reshape_safe
= MaxSector
;
4175 mddev
->reshape_position
= MaxSector
;
4176 spin_unlock_irq(&conf
->device_lock
);
4180 /* Calculate the last device-address that could contain
4181 * any block from the chunk that includes the array-address 's'
4182 * and report the next address.
4183 * i.e. the address returned will be chunk-aligned and after
4184 * any data that is in the chunk containing 's'.
4186 static sector_t
last_dev_address(sector_t s
, struct geom
*geo
)
4188 s
= (s
| geo
->chunk_mask
) + 1;
4189 s
>>= geo
->chunk_shift
;
4190 s
*= geo
->near_copies
;
4191 s
= DIV_ROUND_UP_SECTOR_T(s
, geo
->raid_disks
);
4192 s
*= geo
->far_copies
;
4193 s
<<= geo
->chunk_shift
;
4197 /* Calculate the first device-address that could contain
4198 * any block from the chunk that includes the array-address 's'.
4199 * This too will be the start of a chunk
4201 static sector_t
first_dev_address(sector_t s
, struct geom
*geo
)
4203 s
>>= geo
->chunk_shift
;
4204 s
*= geo
->near_copies
;
4205 sector_div(s
, geo
->raid_disks
);
4206 s
*= geo
->far_copies
;
4207 s
<<= geo
->chunk_shift
;
4211 static sector_t
reshape_request(struct mddev
*mddev
, sector_t sector_nr
,
4214 /* We simply copy at most one chunk (smallest of old and new)
4215 * at a time, possibly less if that exceeds RESYNC_PAGES,
4216 * or we hit a bad block or something.
4217 * This might mean we pause for normal IO in the middle of
4218 * a chunk, but that is not a problem was mddev->reshape_position
4219 * can record any location.
4221 * If we will want to write to a location that isn't
4222 * yet recorded as 'safe' (i.e. in metadata on disk) then
4223 * we need to flush all reshape requests and update the metadata.
4225 * When reshaping forwards (e.g. to more devices), we interpret
4226 * 'safe' as the earliest block which might not have been copied
4227 * down yet. We divide this by previous stripe size and multiply
4228 * by previous stripe length to get lowest device offset that we
4229 * cannot write to yet.
4230 * We interpret 'sector_nr' as an address that we want to write to.
4231 * From this we use last_device_address() to find where we might
4232 * write to, and first_device_address on the 'safe' position.
4233 * If this 'next' write position is after the 'safe' position,
4234 * we must update the metadata to increase the 'safe' position.
4236 * When reshaping backwards, we round in the opposite direction
4237 * and perform the reverse test: next write position must not be
4238 * less than current safe position.
4240 * In all this the minimum difference in data offsets
4241 * (conf->offset_diff - always positive) allows a bit of slack,
4242 * so next can be after 'safe', but not by more than offset_disk
4244 * We need to prepare all the bios here before we start any IO
4245 * to ensure the size we choose is acceptable to all devices.
4246 * The means one for each copy for write-out and an extra one for
4248 * We store the read-in bio in ->master_bio and the others in
4249 * ->devs[x].bio and ->devs[x].repl_bio.
4251 struct r10conf
*conf
= mddev
->private;
4252 struct r10bio
*r10_bio
;
4253 sector_t next
, safe
, last
;
4257 struct md_rdev
*rdev
;
4260 struct bio
*bio
, *read_bio
;
4261 int sectors_done
= 0;
4263 if (sector_nr
== 0) {
4264 /* If restarting in the middle, skip the initial sectors */
4265 if (mddev
->reshape_backwards
&&
4266 conf
->reshape_progress
< raid10_size(mddev
, 0, 0)) {
4267 sector_nr
= (raid10_size(mddev
, 0, 0)
4268 - conf
->reshape_progress
);
4269 } else if (!mddev
->reshape_backwards
&&
4270 conf
->reshape_progress
> 0)
4271 sector_nr
= conf
->reshape_progress
;
4273 mddev
->curr_resync_completed
= sector_nr
;
4274 sysfs_notify(&mddev
->kobj
, NULL
, "sync_completed");
4280 /* We don't use sector_nr to track where we are up to
4281 * as that doesn't work well for ->reshape_backwards.
4282 * So just use ->reshape_progress.
4284 if (mddev
->reshape_backwards
) {
4285 /* 'next' is the earliest device address that we might
4286 * write to for this chunk in the new layout
4288 next
= first_dev_address(conf
->reshape_progress
- 1,
4291 /* 'safe' is the last device address that we might read from
4292 * in the old layout after a restart
4294 safe
= last_dev_address(conf
->reshape_safe
- 1,
4297 if (next
+ conf
->offset_diff
< safe
)
4300 last
= conf
->reshape_progress
- 1;
4301 sector_nr
= last
& ~(sector_t
)(conf
->geo
.chunk_mask
4302 & conf
->prev
.chunk_mask
);
4303 if (sector_nr
+ RESYNC_BLOCK_SIZE
/512 < last
)
4304 sector_nr
= last
+ 1 - RESYNC_BLOCK_SIZE
/512;
4306 /* 'next' is after the last device address that we
4307 * might write to for this chunk in the new layout
4309 next
= last_dev_address(conf
->reshape_progress
, &conf
->geo
);
4311 /* 'safe' is the earliest device address that we might
4312 * read from in the old layout after a restart
4314 safe
= first_dev_address(conf
->reshape_safe
, &conf
->prev
);
4316 /* Need to update metadata if 'next' might be beyond 'safe'
4317 * as that would possibly corrupt data
4319 if (next
> safe
+ conf
->offset_diff
)
4322 sector_nr
= conf
->reshape_progress
;
4323 last
= sector_nr
| (conf
->geo
.chunk_mask
4324 & conf
->prev
.chunk_mask
);
4326 if (sector_nr
+ RESYNC_BLOCK_SIZE
/512 <= last
)
4327 last
= sector_nr
+ RESYNC_BLOCK_SIZE
/512 - 1;
4331 time_after(jiffies
, conf
->reshape_checkpoint
+ 10*HZ
)) {
4332 /* Need to update reshape_position in metadata */
4334 mddev
->reshape_position
= conf
->reshape_progress
;
4335 if (mddev
->reshape_backwards
)
4336 mddev
->curr_resync_completed
= raid10_size(mddev
, 0, 0)
4337 - conf
->reshape_progress
;
4339 mddev
->curr_resync_completed
= conf
->reshape_progress
;
4340 conf
->reshape_checkpoint
= jiffies
;
4341 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
4342 md_wakeup_thread(mddev
->thread
);
4343 wait_event(mddev
->sb_wait
, mddev
->flags
== 0 ||
4344 test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
));
4345 if (test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
)) {
4346 allow_barrier(conf
);
4347 return sectors_done
;
4349 conf
->reshape_safe
= mddev
->reshape_position
;
4350 allow_barrier(conf
);
4354 /* Now schedule reads for blocks from sector_nr to last */
4355 r10_bio
= mempool_alloc(conf
->r10buf_pool
, GFP_NOIO
);
4357 raise_barrier(conf
, sectors_done
!= 0);
4358 atomic_set(&r10_bio
->remaining
, 0);
4359 r10_bio
->mddev
= mddev
;
4360 r10_bio
->sector
= sector_nr
;
4361 set_bit(R10BIO_IsReshape
, &r10_bio
->state
);
4362 r10_bio
->sectors
= last
- sector_nr
+ 1;
4363 rdev
= read_balance(conf
, r10_bio
, &max_sectors
);
4364 BUG_ON(!test_bit(R10BIO_Previous
, &r10_bio
->state
));
4367 /* Cannot read from here, so need to record bad blocks
4368 * on all the target devices.
4371 mempool_free(r10_bio
, conf
->r10buf_pool
);
4372 set_bit(MD_RECOVERY_INTR
, &mddev
->recovery
);
4373 return sectors_done
;
4376 read_bio
= bio_alloc_mddev(GFP_KERNEL
, RESYNC_PAGES
, mddev
);
4378 read_bio
->bi_bdev
= rdev
->bdev
;
4379 read_bio
->bi_iter
.bi_sector
= (r10_bio
->devs
[r10_bio
->read_slot
].addr
4380 + rdev
->data_offset
);
4381 read_bio
->bi_private
= r10_bio
;
4382 read_bio
->bi_end_io
= end_sync_read
;
4383 read_bio
->bi_rw
= READ
;
4384 read_bio
->bi_flags
&= (~0UL << BIO_RESET_BITS
);
4385 __set_bit(BIO_UPTODATE
, &read_bio
->bi_flags
);
4386 read_bio
->bi_vcnt
= 0;
4387 read_bio
->bi_iter
.bi_size
= 0;
4388 r10_bio
->master_bio
= read_bio
;
4389 r10_bio
->read_slot
= r10_bio
->devs
[r10_bio
->read_slot
].devnum
;
4391 /* Now find the locations in the new layout */
4392 __raid10_find_phys(&conf
->geo
, r10_bio
);
4395 read_bio
->bi_next
= NULL
;
4397 for (s
= 0; s
< conf
->copies
*2; s
++) {
4399 int d
= r10_bio
->devs
[s
/2].devnum
;
4400 struct md_rdev
*rdev2
;
4402 rdev2
= conf
->mirrors
[d
].replacement
;
4403 b
= r10_bio
->devs
[s
/2].repl_bio
;
4405 rdev2
= conf
->mirrors
[d
].rdev
;
4406 b
= r10_bio
->devs
[s
/2].bio
;
4408 if (!rdev2
|| test_bit(Faulty
, &rdev2
->flags
))
4412 b
->bi_bdev
= rdev2
->bdev
;
4413 b
->bi_iter
.bi_sector
= r10_bio
->devs
[s
/2].addr
+
4414 rdev2
->new_data_offset
;
4415 b
->bi_private
= r10_bio
;
4416 b
->bi_end_io
= end_reshape_write
;
4422 /* Now add as many pages as possible to all of these bios. */
4425 for (s
= 0 ; s
< max_sectors
; s
+= PAGE_SIZE
>> 9) {
4426 struct page
*page
= r10_bio
->devs
[0].bio
->bi_io_vec
[s
/(PAGE_SIZE
>>9)].bv_page
;
4427 int len
= (max_sectors
- s
) << 9;
4428 if (len
> PAGE_SIZE
)
4430 for (bio
= blist
; bio
; bio
= bio
->bi_next
) {
4432 if (bio_add_page(bio
, page
, len
, 0))
4435 /* Didn't fit, must stop */
4437 bio2
&& bio2
!= bio
;
4438 bio2
= bio2
->bi_next
) {
4439 /* Remove last page from this bio */
4441 bio2
->bi_iter
.bi_size
-= len
;
4442 __clear_bit(BIO_SEG_VALID
, &bio2
->bi_flags
);
4446 sector_nr
+= len
>> 9;
4447 nr_sectors
+= len
>> 9;
4450 r10_bio
->sectors
= nr_sectors
;
4452 /* Now submit the read */
4453 md_sync_acct(read_bio
->bi_bdev
, r10_bio
->sectors
);
4454 atomic_inc(&r10_bio
->remaining
);
4455 read_bio
->bi_next
= NULL
;
4456 generic_make_request(read_bio
);
4457 sector_nr
+= nr_sectors
;
4458 sectors_done
+= nr_sectors
;
4459 if (sector_nr
<= last
)
4462 /* Now that we have done the whole section we can
4463 * update reshape_progress
4465 if (mddev
->reshape_backwards
)
4466 conf
->reshape_progress
-= sectors_done
;
4468 conf
->reshape_progress
+= sectors_done
;
4470 return sectors_done
;
4473 static void end_reshape_request(struct r10bio
*r10_bio
);
4474 static int handle_reshape_read_error(struct mddev
*mddev
,
4475 struct r10bio
*r10_bio
);
4476 static void reshape_request_write(struct mddev
*mddev
, struct r10bio
*r10_bio
)
4478 /* Reshape read completed. Hopefully we have a block
4480 * If we got a read error then we do sync 1-page reads from
4481 * elsewhere until we find the data - or give up.
4483 struct r10conf
*conf
= mddev
->private;
4486 if (!test_bit(R10BIO_Uptodate
, &r10_bio
->state
))
4487 if (handle_reshape_read_error(mddev
, r10_bio
) < 0) {
4488 /* Reshape has been aborted */
4489 md_done_sync(mddev
, r10_bio
->sectors
, 0);
4493 /* We definitely have the data in the pages, schedule the
4496 atomic_set(&r10_bio
->remaining
, 1);
4497 for (s
= 0; s
< conf
->copies
*2; s
++) {
4499 int d
= r10_bio
->devs
[s
/2].devnum
;
4500 struct md_rdev
*rdev
;
4502 rdev
= conf
->mirrors
[d
].replacement
;
4503 b
= r10_bio
->devs
[s
/2].repl_bio
;
4505 rdev
= conf
->mirrors
[d
].rdev
;
4506 b
= r10_bio
->devs
[s
/2].bio
;
4508 if (!rdev
|| test_bit(Faulty
, &rdev
->flags
))
4510 atomic_inc(&rdev
->nr_pending
);
4511 md_sync_acct(b
->bi_bdev
, r10_bio
->sectors
);
4512 atomic_inc(&r10_bio
->remaining
);
4514 generic_make_request(b
);
4516 end_reshape_request(r10_bio
);
4519 static void end_reshape(struct r10conf
*conf
)
4521 if (test_bit(MD_RECOVERY_INTR
, &conf
->mddev
->recovery
))
4524 spin_lock_irq(&conf
->device_lock
);
4525 conf
->prev
= conf
->geo
;
4526 md_finish_reshape(conf
->mddev
);
4528 conf
->reshape_progress
= MaxSector
;
4529 conf
->reshape_safe
= MaxSector
;
4530 spin_unlock_irq(&conf
->device_lock
);
4532 /* read-ahead size must cover two whole stripes, which is
4533 * 2 * (datadisks) * chunksize where 'n' is the number of raid devices
4535 if (conf
->mddev
->queue
) {
4536 int stripe
= conf
->geo
.raid_disks
*
4537 ((conf
->mddev
->chunk_sectors
<< 9) / PAGE_SIZE
);
4538 stripe
/= conf
->geo
.near_copies
;
4539 if (conf
->mddev
->queue
->backing_dev_info
.ra_pages
< 2 * stripe
)
4540 conf
->mddev
->queue
->backing_dev_info
.ra_pages
= 2 * stripe
;
4545 static int handle_reshape_read_error(struct mddev
*mddev
,
4546 struct r10bio
*r10_bio
)
4548 /* Use sync reads to get the blocks from somewhere else */
4549 int sectors
= r10_bio
->sectors
;
4550 struct r10conf
*conf
= mddev
->private;
4552 struct r10bio r10_bio
;
4553 struct r10dev devs
[conf
->copies
];
4555 struct r10bio
*r10b
= &on_stack
.r10_bio
;
4558 struct bio_vec
*bvec
= r10_bio
->master_bio
->bi_io_vec
;
4560 r10b
->sector
= r10_bio
->sector
;
4561 __raid10_find_phys(&conf
->prev
, r10b
);
4566 int first_slot
= slot
;
4568 if (s
> (PAGE_SIZE
>> 9))
4572 int d
= r10b
->devs
[slot
].devnum
;
4573 struct md_rdev
*rdev
= conf
->mirrors
[d
].rdev
;
4576 test_bit(Faulty
, &rdev
->flags
) ||
4577 !test_bit(In_sync
, &rdev
->flags
))
4580 addr
= r10b
->devs
[slot
].addr
+ idx
* PAGE_SIZE
;
4581 success
= sync_page_io(rdev
,
4590 if (slot
>= conf
->copies
)
4592 if (slot
== first_slot
)
4596 /* couldn't read this block, must give up */
4597 set_bit(MD_RECOVERY_INTR
,
4607 static void end_reshape_write(struct bio
*bio
, int error
)
4609 int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
4610 struct r10bio
*r10_bio
= bio
->bi_private
;
4611 struct mddev
*mddev
= r10_bio
->mddev
;
4612 struct r10conf
*conf
= mddev
->private;
4616 struct md_rdev
*rdev
= NULL
;
4618 d
= find_bio_disk(conf
, r10_bio
, bio
, &slot
, &repl
);
4620 rdev
= conf
->mirrors
[d
].replacement
;
4623 rdev
= conf
->mirrors
[d
].rdev
;
4627 /* FIXME should record badblock */
4628 md_error(mddev
, rdev
);
4631 rdev_dec_pending(rdev
, mddev
);
4632 end_reshape_request(r10_bio
);
4635 static void end_reshape_request(struct r10bio
*r10_bio
)
4637 if (!atomic_dec_and_test(&r10_bio
->remaining
))
4639 md_done_sync(r10_bio
->mddev
, r10_bio
->sectors
, 1);
4640 bio_put(r10_bio
->master_bio
);
4644 static void raid10_finish_reshape(struct mddev
*mddev
)
4646 struct r10conf
*conf
= mddev
->private;
4648 if (test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
))
4651 if (mddev
->delta_disks
> 0) {
4652 sector_t size
= raid10_size(mddev
, 0, 0);
4653 md_set_array_sectors(mddev
, size
);
4654 if (mddev
->recovery_cp
> mddev
->resync_max_sectors
) {
4655 mddev
->recovery_cp
= mddev
->resync_max_sectors
;
4656 set_bit(MD_RECOVERY_NEEDED
, &mddev
->recovery
);
4658 mddev
->resync_max_sectors
= size
;
4659 set_capacity(mddev
->gendisk
, mddev
->array_sectors
);
4660 revalidate_disk(mddev
->gendisk
);
4663 for (d
= conf
->geo
.raid_disks
;
4664 d
< conf
->geo
.raid_disks
- mddev
->delta_disks
;
4666 struct md_rdev
*rdev
= conf
->mirrors
[d
].rdev
;
4668 clear_bit(In_sync
, &rdev
->flags
);
4669 rdev
= conf
->mirrors
[d
].replacement
;
4671 clear_bit(In_sync
, &rdev
->flags
);
4674 mddev
->layout
= mddev
->new_layout
;
4675 mddev
->chunk_sectors
= 1 << conf
->geo
.chunk_shift
;
4676 mddev
->reshape_position
= MaxSector
;
4677 mddev
->delta_disks
= 0;
4678 mddev
->reshape_backwards
= 0;
4681 static struct md_personality raid10_personality
=
4685 .owner
= THIS_MODULE
,
4686 .make_request
= make_request
,
4688 .free
= raid10_free
,
4690 .error_handler
= error
,
4691 .hot_add_disk
= raid10_add_disk
,
4692 .hot_remove_disk
= raid10_remove_disk
,
4693 .spare_active
= raid10_spare_active
,
4694 .sync_request
= sync_request
,
4695 .quiesce
= raid10_quiesce
,
4696 .size
= raid10_size
,
4697 .resize
= raid10_resize
,
4698 .takeover
= raid10_takeover
,
4699 .check_reshape
= raid10_check_reshape
,
4700 .start_reshape
= raid10_start_reshape
,
4701 .finish_reshape
= raid10_finish_reshape
,
4702 .congested
= raid10_congested
,
4703 .mergeable_bvec
= raid10_mergeable_bvec
,
4706 static int __init
raid_init(void)
4708 return register_md_personality(&raid10_personality
);
4711 static void raid_exit(void)
4713 unregister_md_personality(&raid10_personality
);
4716 module_init(raid_init
);
4717 module_exit(raid_exit
);
4718 MODULE_LICENSE("GPL");
4719 MODULE_DESCRIPTION("RAID10 (striped mirror) personality for MD");
4720 MODULE_ALIAS("md-personality-9"); /* RAID10 */
4721 MODULE_ALIAS("md-raid10");
4722 MODULE_ALIAS("md-level-10");
4724 module_param(max_queued_requests
, int, S_IRUGO
|S_IWUSR
);