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 << BDI_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
;
2103 for (j
=0; j
< vcnt
; j
++) {
2104 tbio
->bi_io_vec
[j
].bv_offset
= 0;
2105 tbio
->bi_io_vec
[j
].bv_len
= PAGE_SIZE
;
2107 memcpy(page_address(tbio
->bi_io_vec
[j
].bv_page
),
2108 page_address(fbio
->bi_io_vec
[j
].bv_page
),
2111 tbio
->bi_end_io
= end_sync_write
;
2113 d
= r10_bio
->devs
[i
].devnum
;
2114 atomic_inc(&conf
->mirrors
[d
].rdev
->nr_pending
);
2115 atomic_inc(&r10_bio
->remaining
);
2116 md_sync_acct(conf
->mirrors
[d
].rdev
->bdev
, bio_sectors(tbio
));
2118 tbio
->bi_iter
.bi_sector
+= conf
->mirrors
[d
].rdev
->data_offset
;
2119 tbio
->bi_bdev
= conf
->mirrors
[d
].rdev
->bdev
;
2120 generic_make_request(tbio
);
2123 /* Now write out to any replacement devices
2126 for (i
= 0; i
< conf
->copies
; i
++) {
2129 tbio
= r10_bio
->devs
[i
].repl_bio
;
2130 if (!tbio
|| !tbio
->bi_end_io
)
2132 if (r10_bio
->devs
[i
].bio
->bi_end_io
!= end_sync_write
2133 && r10_bio
->devs
[i
].bio
!= fbio
)
2134 for (j
= 0; j
< vcnt
; j
++)
2135 memcpy(page_address(tbio
->bi_io_vec
[j
].bv_page
),
2136 page_address(fbio
->bi_io_vec
[j
].bv_page
),
2138 d
= r10_bio
->devs
[i
].devnum
;
2139 atomic_inc(&r10_bio
->remaining
);
2140 md_sync_acct(conf
->mirrors
[d
].replacement
->bdev
,
2142 generic_make_request(tbio
);
2146 if (atomic_dec_and_test(&r10_bio
->remaining
)) {
2147 md_done_sync(mddev
, r10_bio
->sectors
, 1);
2153 * Now for the recovery code.
2154 * Recovery happens across physical sectors.
2155 * We recover all non-is_sync drives by finding the virtual address of
2156 * each, and then choose a working drive that also has that virt address.
2157 * There is a separate r10_bio for each non-in_sync drive.
2158 * Only the first two slots are in use. The first for reading,
2159 * The second for writing.
2162 static void fix_recovery_read_error(struct r10bio
*r10_bio
)
2164 /* We got a read error during recovery.
2165 * We repeat the read in smaller page-sized sections.
2166 * If a read succeeds, write it to the new device or record
2167 * a bad block if we cannot.
2168 * If a read fails, record a bad block on both old and
2171 struct mddev
*mddev
= r10_bio
->mddev
;
2172 struct r10conf
*conf
= mddev
->private;
2173 struct bio
*bio
= r10_bio
->devs
[0].bio
;
2175 int sectors
= r10_bio
->sectors
;
2177 int dr
= r10_bio
->devs
[0].devnum
;
2178 int dw
= r10_bio
->devs
[1].devnum
;
2182 struct md_rdev
*rdev
;
2186 if (s
> (PAGE_SIZE
>>9))
2189 rdev
= conf
->mirrors
[dr
].rdev
;
2190 addr
= r10_bio
->devs
[0].addr
+ sect
,
2191 ok
= sync_page_io(rdev
,
2194 bio
->bi_io_vec
[idx
].bv_page
,
2197 rdev
= conf
->mirrors
[dw
].rdev
;
2198 addr
= r10_bio
->devs
[1].addr
+ sect
;
2199 ok
= sync_page_io(rdev
,
2202 bio
->bi_io_vec
[idx
].bv_page
,
2205 set_bit(WriteErrorSeen
, &rdev
->flags
);
2206 if (!test_and_set_bit(WantReplacement
,
2208 set_bit(MD_RECOVERY_NEEDED
,
2209 &rdev
->mddev
->recovery
);
2213 /* We don't worry if we cannot set a bad block -
2214 * it really is bad so there is no loss in not
2217 rdev_set_badblocks(rdev
, addr
, s
, 0);
2219 if (rdev
!= conf
->mirrors
[dw
].rdev
) {
2220 /* need bad block on destination too */
2221 struct md_rdev
*rdev2
= conf
->mirrors
[dw
].rdev
;
2222 addr
= r10_bio
->devs
[1].addr
+ sect
;
2223 ok
= rdev_set_badblocks(rdev2
, addr
, s
, 0);
2225 /* just abort the recovery */
2227 "md/raid10:%s: recovery aborted"
2228 " due to read error\n",
2231 conf
->mirrors
[dw
].recovery_disabled
2232 = mddev
->recovery_disabled
;
2233 set_bit(MD_RECOVERY_INTR
,
2246 static void recovery_request_write(struct mddev
*mddev
, struct r10bio
*r10_bio
)
2248 struct r10conf
*conf
= mddev
->private;
2250 struct bio
*wbio
, *wbio2
;
2252 if (!test_bit(R10BIO_Uptodate
, &r10_bio
->state
)) {
2253 fix_recovery_read_error(r10_bio
);
2254 end_sync_request(r10_bio
);
2259 * share the pages with the first bio
2260 * and submit the write request
2262 d
= r10_bio
->devs
[1].devnum
;
2263 wbio
= r10_bio
->devs
[1].bio
;
2264 wbio2
= r10_bio
->devs
[1].repl_bio
;
2265 /* Need to test wbio2->bi_end_io before we call
2266 * generic_make_request as if the former is NULL,
2267 * the latter is free to free wbio2.
2269 if (wbio2
&& !wbio2
->bi_end_io
)
2271 if (wbio
->bi_end_io
) {
2272 atomic_inc(&conf
->mirrors
[d
].rdev
->nr_pending
);
2273 md_sync_acct(conf
->mirrors
[d
].rdev
->bdev
, bio_sectors(wbio
));
2274 generic_make_request(wbio
);
2277 atomic_inc(&conf
->mirrors
[d
].replacement
->nr_pending
);
2278 md_sync_acct(conf
->mirrors
[d
].replacement
->bdev
,
2279 bio_sectors(wbio2
));
2280 generic_make_request(wbio2
);
2285 * Used by fix_read_error() to decay the per rdev read_errors.
2286 * We halve the read error count for every hour that has elapsed
2287 * since the last recorded read error.
2290 static void check_decay_read_errors(struct mddev
*mddev
, struct md_rdev
*rdev
)
2292 struct timespec cur_time_mon
;
2293 unsigned long hours_since_last
;
2294 unsigned int read_errors
= atomic_read(&rdev
->read_errors
);
2296 ktime_get_ts(&cur_time_mon
);
2298 if (rdev
->last_read_error
.tv_sec
== 0 &&
2299 rdev
->last_read_error
.tv_nsec
== 0) {
2300 /* first time we've seen a read error */
2301 rdev
->last_read_error
= cur_time_mon
;
2305 hours_since_last
= (cur_time_mon
.tv_sec
-
2306 rdev
->last_read_error
.tv_sec
) / 3600;
2308 rdev
->last_read_error
= cur_time_mon
;
2311 * if hours_since_last is > the number of bits in read_errors
2312 * just set read errors to 0. We do this to avoid
2313 * overflowing the shift of read_errors by hours_since_last.
2315 if (hours_since_last
>= 8 * sizeof(read_errors
))
2316 atomic_set(&rdev
->read_errors
, 0);
2318 atomic_set(&rdev
->read_errors
, read_errors
>> hours_since_last
);
2321 static int r10_sync_page_io(struct md_rdev
*rdev
, sector_t sector
,
2322 int sectors
, struct page
*page
, int rw
)
2327 if (is_badblock(rdev
, sector
, sectors
, &first_bad
, &bad_sectors
)
2328 && (rw
== READ
|| test_bit(WriteErrorSeen
, &rdev
->flags
)))
2330 if (sync_page_io(rdev
, sector
, sectors
<< 9, page
, rw
, false))
2334 set_bit(WriteErrorSeen
, &rdev
->flags
);
2335 if (!test_and_set_bit(WantReplacement
, &rdev
->flags
))
2336 set_bit(MD_RECOVERY_NEEDED
,
2337 &rdev
->mddev
->recovery
);
2339 /* need to record an error - either for the block or the device */
2340 if (!rdev_set_badblocks(rdev
, sector
, sectors
, 0))
2341 md_error(rdev
->mddev
, rdev
);
2346 * This is a kernel thread which:
2348 * 1. Retries failed read operations on working mirrors.
2349 * 2. Updates the raid superblock when problems encounter.
2350 * 3. Performs writes following reads for array synchronising.
2353 static void fix_read_error(struct r10conf
*conf
, struct mddev
*mddev
, struct r10bio
*r10_bio
)
2355 int sect
= 0; /* Offset from r10_bio->sector */
2356 int sectors
= r10_bio
->sectors
;
2357 struct md_rdev
*rdev
;
2358 int max_read_errors
= atomic_read(&mddev
->max_corr_read_errors
);
2359 int d
= r10_bio
->devs
[r10_bio
->read_slot
].devnum
;
2361 /* still own a reference to this rdev, so it cannot
2362 * have been cleared recently.
2364 rdev
= conf
->mirrors
[d
].rdev
;
2366 if (test_bit(Faulty
, &rdev
->flags
))
2367 /* drive has already been failed, just ignore any
2368 more fix_read_error() attempts */
2371 check_decay_read_errors(mddev
, rdev
);
2372 atomic_inc(&rdev
->read_errors
);
2373 if (atomic_read(&rdev
->read_errors
) > max_read_errors
) {
2374 char b
[BDEVNAME_SIZE
];
2375 bdevname(rdev
->bdev
, b
);
2378 "md/raid10:%s: %s: Raid device exceeded "
2379 "read_error threshold [cur %d:max %d]\n",
2381 atomic_read(&rdev
->read_errors
), max_read_errors
);
2383 "md/raid10:%s: %s: Failing raid device\n",
2385 md_error(mddev
, conf
->mirrors
[d
].rdev
);
2386 r10_bio
->devs
[r10_bio
->read_slot
].bio
= IO_BLOCKED
;
2392 int sl
= r10_bio
->read_slot
;
2396 if (s
> (PAGE_SIZE
>>9))
2404 d
= r10_bio
->devs
[sl
].devnum
;
2405 rdev
= rcu_dereference(conf
->mirrors
[d
].rdev
);
2407 !test_bit(Unmerged
, &rdev
->flags
) &&
2408 test_bit(In_sync
, &rdev
->flags
) &&
2409 is_badblock(rdev
, r10_bio
->devs
[sl
].addr
+ sect
, s
,
2410 &first_bad
, &bad_sectors
) == 0) {
2411 atomic_inc(&rdev
->nr_pending
);
2413 success
= sync_page_io(rdev
,
2414 r10_bio
->devs
[sl
].addr
+
2417 conf
->tmppage
, READ
, false);
2418 rdev_dec_pending(rdev
, mddev
);
2424 if (sl
== conf
->copies
)
2426 } while (!success
&& sl
!= r10_bio
->read_slot
);
2430 /* Cannot read from anywhere, just mark the block
2431 * as bad on the first device to discourage future
2434 int dn
= r10_bio
->devs
[r10_bio
->read_slot
].devnum
;
2435 rdev
= conf
->mirrors
[dn
].rdev
;
2437 if (!rdev_set_badblocks(
2439 r10_bio
->devs
[r10_bio
->read_slot
].addr
2442 md_error(mddev
, rdev
);
2443 r10_bio
->devs
[r10_bio
->read_slot
].bio
2450 /* write it back and re-read */
2452 while (sl
!= r10_bio
->read_slot
) {
2453 char b
[BDEVNAME_SIZE
];
2458 d
= r10_bio
->devs
[sl
].devnum
;
2459 rdev
= rcu_dereference(conf
->mirrors
[d
].rdev
);
2461 test_bit(Unmerged
, &rdev
->flags
) ||
2462 !test_bit(In_sync
, &rdev
->flags
))
2465 atomic_inc(&rdev
->nr_pending
);
2467 if (r10_sync_page_io(rdev
,
2468 r10_bio
->devs
[sl
].addr
+
2470 s
, conf
->tmppage
, WRITE
)
2472 /* Well, this device is dead */
2474 "md/raid10:%s: read correction "
2476 " (%d sectors at %llu on %s)\n",
2478 (unsigned long long)(
2480 choose_data_offset(r10_bio
,
2482 bdevname(rdev
->bdev
, b
));
2483 printk(KERN_NOTICE
"md/raid10:%s: %s: failing "
2486 bdevname(rdev
->bdev
, b
));
2488 rdev_dec_pending(rdev
, mddev
);
2492 while (sl
!= r10_bio
->read_slot
) {
2493 char b
[BDEVNAME_SIZE
];
2498 d
= r10_bio
->devs
[sl
].devnum
;
2499 rdev
= rcu_dereference(conf
->mirrors
[d
].rdev
);
2501 !test_bit(In_sync
, &rdev
->flags
))
2504 atomic_inc(&rdev
->nr_pending
);
2506 switch (r10_sync_page_io(rdev
,
2507 r10_bio
->devs
[sl
].addr
+
2512 /* Well, this device is dead */
2514 "md/raid10:%s: unable to read back "
2516 " (%d sectors at %llu on %s)\n",
2518 (unsigned long long)(
2520 choose_data_offset(r10_bio
, rdev
)),
2521 bdevname(rdev
->bdev
, b
));
2522 printk(KERN_NOTICE
"md/raid10:%s: %s: failing "
2525 bdevname(rdev
->bdev
, b
));
2529 "md/raid10:%s: read error corrected"
2530 " (%d sectors at %llu on %s)\n",
2532 (unsigned long long)(
2534 choose_data_offset(r10_bio
, rdev
)),
2535 bdevname(rdev
->bdev
, b
));
2536 atomic_add(s
, &rdev
->corrected_errors
);
2539 rdev_dec_pending(rdev
, mddev
);
2549 static int narrow_write_error(struct r10bio
*r10_bio
, int i
)
2551 struct bio
*bio
= r10_bio
->master_bio
;
2552 struct mddev
*mddev
= r10_bio
->mddev
;
2553 struct r10conf
*conf
= mddev
->private;
2554 struct md_rdev
*rdev
= conf
->mirrors
[r10_bio
->devs
[i
].devnum
].rdev
;
2555 /* bio has the data to be written to slot 'i' where
2556 * we just recently had a write error.
2557 * We repeatedly clone the bio and trim down to one block,
2558 * then try the write. Where the write fails we record
2560 * It is conceivable that the bio doesn't exactly align with
2561 * blocks. We must handle this.
2563 * We currently own a reference to the rdev.
2569 int sect_to_write
= r10_bio
->sectors
;
2572 if (rdev
->badblocks
.shift
< 0)
2575 block_sectors
= roundup(1 << rdev
->badblocks
.shift
,
2576 bdev_logical_block_size(rdev
->bdev
) >> 9);
2577 sector
= r10_bio
->sector
;
2578 sectors
= ((r10_bio
->sector
+ block_sectors
)
2579 & ~(sector_t
)(block_sectors
- 1))
2582 while (sect_to_write
) {
2584 if (sectors
> sect_to_write
)
2585 sectors
= sect_to_write
;
2586 /* Write at 'sector' for 'sectors' */
2587 wbio
= bio_clone_mddev(bio
, GFP_NOIO
, mddev
);
2588 bio_trim(wbio
, sector
- bio
->bi_iter
.bi_sector
, sectors
);
2589 wbio
->bi_iter
.bi_sector
= (r10_bio
->devs
[i
].addr
+
2590 choose_data_offset(r10_bio
, rdev
) +
2591 (sector
- r10_bio
->sector
));
2592 wbio
->bi_bdev
= rdev
->bdev
;
2593 if (submit_bio_wait(WRITE
, wbio
) == 0)
2595 ok
= rdev_set_badblocks(rdev
, sector
,
2600 sect_to_write
-= sectors
;
2602 sectors
= block_sectors
;
2607 static void handle_read_error(struct mddev
*mddev
, struct r10bio
*r10_bio
)
2609 int slot
= r10_bio
->read_slot
;
2611 struct r10conf
*conf
= mddev
->private;
2612 struct md_rdev
*rdev
= r10_bio
->devs
[slot
].rdev
;
2613 char b
[BDEVNAME_SIZE
];
2614 unsigned long do_sync
;
2617 /* we got a read error. Maybe the drive is bad. Maybe just
2618 * the block and we can fix it.
2619 * We freeze all other IO, and try reading the block from
2620 * other devices. When we find one, we re-write
2621 * and check it that fixes the read error.
2622 * This is all done synchronously while the array is
2625 bio
= r10_bio
->devs
[slot
].bio
;
2626 bdevname(bio
->bi_bdev
, b
);
2628 r10_bio
->devs
[slot
].bio
= NULL
;
2630 if (mddev
->ro
== 0) {
2631 freeze_array(conf
, 1);
2632 fix_read_error(conf
, mddev
, r10_bio
);
2633 unfreeze_array(conf
);
2635 r10_bio
->devs
[slot
].bio
= IO_BLOCKED
;
2637 rdev_dec_pending(rdev
, mddev
);
2640 rdev
= read_balance(conf
, r10_bio
, &max_sectors
);
2642 printk(KERN_ALERT
"md/raid10:%s: %s: unrecoverable I/O"
2643 " read error for block %llu\n",
2645 (unsigned long long)r10_bio
->sector
);
2646 raid_end_bio_io(r10_bio
);
2650 do_sync
= (r10_bio
->master_bio
->bi_rw
& REQ_SYNC
);
2651 slot
= r10_bio
->read_slot
;
2654 "md/raid10:%s: %s: redirecting "
2655 "sector %llu to another mirror\n",
2657 bdevname(rdev
->bdev
, b
),
2658 (unsigned long long)r10_bio
->sector
);
2659 bio
= bio_clone_mddev(r10_bio
->master_bio
,
2661 bio_trim(bio
, r10_bio
->sector
- bio
->bi_iter
.bi_sector
, max_sectors
);
2662 r10_bio
->devs
[slot
].bio
= bio
;
2663 r10_bio
->devs
[slot
].rdev
= rdev
;
2664 bio
->bi_iter
.bi_sector
= r10_bio
->devs
[slot
].addr
2665 + choose_data_offset(r10_bio
, rdev
);
2666 bio
->bi_bdev
= rdev
->bdev
;
2667 bio
->bi_rw
= READ
| do_sync
;
2668 bio
->bi_private
= r10_bio
;
2669 bio
->bi_end_io
= raid10_end_read_request
;
2670 if (max_sectors
< r10_bio
->sectors
) {
2671 /* Drat - have to split this up more */
2672 struct bio
*mbio
= r10_bio
->master_bio
;
2673 int sectors_handled
=
2674 r10_bio
->sector
+ max_sectors
2675 - mbio
->bi_iter
.bi_sector
;
2676 r10_bio
->sectors
= max_sectors
;
2677 spin_lock_irq(&conf
->device_lock
);
2678 if (mbio
->bi_phys_segments
== 0)
2679 mbio
->bi_phys_segments
= 2;
2681 mbio
->bi_phys_segments
++;
2682 spin_unlock_irq(&conf
->device_lock
);
2683 generic_make_request(bio
);
2685 r10_bio
= mempool_alloc(conf
->r10bio_pool
,
2687 r10_bio
->master_bio
= mbio
;
2688 r10_bio
->sectors
= bio_sectors(mbio
) - sectors_handled
;
2690 set_bit(R10BIO_ReadError
,
2692 r10_bio
->mddev
= mddev
;
2693 r10_bio
->sector
= mbio
->bi_iter
.bi_sector
2698 generic_make_request(bio
);
2701 static void handle_write_completed(struct r10conf
*conf
, struct r10bio
*r10_bio
)
2703 /* Some sort of write request has finished and it
2704 * succeeded in writing where we thought there was a
2705 * bad block. So forget the bad block.
2706 * Or possibly if failed and we need to record
2710 struct md_rdev
*rdev
;
2712 if (test_bit(R10BIO_IsSync
, &r10_bio
->state
) ||
2713 test_bit(R10BIO_IsRecover
, &r10_bio
->state
)) {
2714 for (m
= 0; m
< conf
->copies
; m
++) {
2715 int dev
= r10_bio
->devs
[m
].devnum
;
2716 rdev
= conf
->mirrors
[dev
].rdev
;
2717 if (r10_bio
->devs
[m
].bio
== NULL
)
2719 if (test_bit(BIO_UPTODATE
,
2720 &r10_bio
->devs
[m
].bio
->bi_flags
)) {
2721 rdev_clear_badblocks(
2723 r10_bio
->devs
[m
].addr
,
2724 r10_bio
->sectors
, 0);
2726 if (!rdev_set_badblocks(
2728 r10_bio
->devs
[m
].addr
,
2729 r10_bio
->sectors
, 0))
2730 md_error(conf
->mddev
, rdev
);
2732 rdev
= conf
->mirrors
[dev
].replacement
;
2733 if (r10_bio
->devs
[m
].repl_bio
== NULL
)
2735 if (test_bit(BIO_UPTODATE
,
2736 &r10_bio
->devs
[m
].repl_bio
->bi_flags
)) {
2737 rdev_clear_badblocks(
2739 r10_bio
->devs
[m
].addr
,
2740 r10_bio
->sectors
, 0);
2742 if (!rdev_set_badblocks(
2744 r10_bio
->devs
[m
].addr
,
2745 r10_bio
->sectors
, 0))
2746 md_error(conf
->mddev
, rdev
);
2751 for (m
= 0; m
< conf
->copies
; m
++) {
2752 int dev
= r10_bio
->devs
[m
].devnum
;
2753 struct bio
*bio
= r10_bio
->devs
[m
].bio
;
2754 rdev
= conf
->mirrors
[dev
].rdev
;
2755 if (bio
== IO_MADE_GOOD
) {
2756 rdev_clear_badblocks(
2758 r10_bio
->devs
[m
].addr
,
2759 r10_bio
->sectors
, 0);
2760 rdev_dec_pending(rdev
, conf
->mddev
);
2761 } else if (bio
!= NULL
&&
2762 !test_bit(BIO_UPTODATE
, &bio
->bi_flags
)) {
2763 if (!narrow_write_error(r10_bio
, m
)) {
2764 md_error(conf
->mddev
, rdev
);
2765 set_bit(R10BIO_Degraded
,
2768 rdev_dec_pending(rdev
, conf
->mddev
);
2770 bio
= r10_bio
->devs
[m
].repl_bio
;
2771 rdev
= conf
->mirrors
[dev
].replacement
;
2772 if (rdev
&& bio
== IO_MADE_GOOD
) {
2773 rdev_clear_badblocks(
2775 r10_bio
->devs
[m
].addr
,
2776 r10_bio
->sectors
, 0);
2777 rdev_dec_pending(rdev
, conf
->mddev
);
2780 if (test_bit(R10BIO_WriteError
,
2782 close_write(r10_bio
);
2783 raid_end_bio_io(r10_bio
);
2787 static void raid10d(struct md_thread
*thread
)
2789 struct mddev
*mddev
= thread
->mddev
;
2790 struct r10bio
*r10_bio
;
2791 unsigned long flags
;
2792 struct r10conf
*conf
= mddev
->private;
2793 struct list_head
*head
= &conf
->retry_list
;
2794 struct blk_plug plug
;
2796 md_check_recovery(mddev
);
2798 blk_start_plug(&plug
);
2801 flush_pending_writes(conf
);
2803 spin_lock_irqsave(&conf
->device_lock
, flags
);
2804 if (list_empty(head
)) {
2805 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
2808 r10_bio
= list_entry(head
->prev
, struct r10bio
, retry_list
);
2809 list_del(head
->prev
);
2811 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
2813 mddev
= r10_bio
->mddev
;
2814 conf
= mddev
->private;
2815 if (test_bit(R10BIO_MadeGood
, &r10_bio
->state
) ||
2816 test_bit(R10BIO_WriteError
, &r10_bio
->state
))
2817 handle_write_completed(conf
, r10_bio
);
2818 else if (test_bit(R10BIO_IsReshape
, &r10_bio
->state
))
2819 reshape_request_write(mddev
, r10_bio
);
2820 else if (test_bit(R10BIO_IsSync
, &r10_bio
->state
))
2821 sync_request_write(mddev
, r10_bio
);
2822 else if (test_bit(R10BIO_IsRecover
, &r10_bio
->state
))
2823 recovery_request_write(mddev
, r10_bio
);
2824 else if (test_bit(R10BIO_ReadError
, &r10_bio
->state
))
2825 handle_read_error(mddev
, r10_bio
);
2827 /* just a partial read to be scheduled from a
2830 int slot
= r10_bio
->read_slot
;
2831 generic_make_request(r10_bio
->devs
[slot
].bio
);
2835 if (mddev
->flags
& ~(1<<MD_CHANGE_PENDING
))
2836 md_check_recovery(mddev
);
2838 blk_finish_plug(&plug
);
2841 static int init_resync(struct r10conf
*conf
)
2846 buffs
= RESYNC_WINDOW
/ RESYNC_BLOCK_SIZE
;
2847 BUG_ON(conf
->r10buf_pool
);
2848 conf
->have_replacement
= 0;
2849 for (i
= 0; i
< conf
->geo
.raid_disks
; i
++)
2850 if (conf
->mirrors
[i
].replacement
)
2851 conf
->have_replacement
= 1;
2852 conf
->r10buf_pool
= mempool_create(buffs
, r10buf_pool_alloc
, r10buf_pool_free
, conf
);
2853 if (!conf
->r10buf_pool
)
2855 conf
->next_resync
= 0;
2860 * perform a "sync" on one "block"
2862 * We need to make sure that no normal I/O request - particularly write
2863 * requests - conflict with active sync requests.
2865 * This is achieved by tracking pending requests and a 'barrier' concept
2866 * that can be installed to exclude normal IO requests.
2868 * Resync and recovery are handled very differently.
2869 * We differentiate by looking at MD_RECOVERY_SYNC in mddev->recovery.
2871 * For resync, we iterate over virtual addresses, read all copies,
2872 * and update if there are differences. If only one copy is live,
2874 * For recovery, we iterate over physical addresses, read a good
2875 * value for each non-in_sync drive, and over-write.
2877 * So, for recovery we may have several outstanding complex requests for a
2878 * given address, one for each out-of-sync device. We model this by allocating
2879 * a number of r10_bio structures, one for each out-of-sync device.
2880 * As we setup these structures, we collect all bio's together into a list
2881 * which we then process collectively to add pages, and then process again
2882 * to pass to generic_make_request.
2884 * The r10_bio structures are linked using a borrowed master_bio pointer.
2885 * This link is counted in ->remaining. When the r10_bio that points to NULL
2886 * has its remaining count decremented to 0, the whole complex operation
2891 static sector_t
sync_request(struct mddev
*mddev
, sector_t sector_nr
,
2894 struct r10conf
*conf
= mddev
->private;
2895 struct r10bio
*r10_bio
;
2896 struct bio
*biolist
= NULL
, *bio
;
2897 sector_t max_sector
, nr_sectors
;
2900 sector_t sync_blocks
;
2901 sector_t sectors_skipped
= 0;
2902 int chunks_skipped
= 0;
2903 sector_t chunk_mask
= conf
->geo
.chunk_mask
;
2905 if (!conf
->r10buf_pool
)
2906 if (init_resync(conf
))
2910 * Allow skipping a full rebuild for incremental assembly
2911 * of a clean array, like RAID1 does.
2913 if (mddev
->bitmap
== NULL
&&
2914 mddev
->recovery_cp
== MaxSector
&&
2915 mddev
->reshape_position
== MaxSector
&&
2916 !test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
) &&
2917 !test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
) &&
2918 !test_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
) &&
2919 conf
->fullsync
== 0) {
2921 return mddev
->dev_sectors
- sector_nr
;
2925 max_sector
= mddev
->dev_sectors
;
2926 if (test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
) ||
2927 test_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
))
2928 max_sector
= mddev
->resync_max_sectors
;
2929 if (sector_nr
>= max_sector
) {
2930 /* If we aborted, we need to abort the
2931 * sync on the 'current' bitmap chucks (there can
2932 * be several when recovering multiple devices).
2933 * as we may have started syncing it but not finished.
2934 * We can find the current address in
2935 * mddev->curr_resync, but for recovery,
2936 * we need to convert that to several
2937 * virtual addresses.
2939 if (test_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
)) {
2945 if (mddev
->curr_resync
< max_sector
) { /* aborted */
2946 if (test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
))
2947 bitmap_end_sync(mddev
->bitmap
, mddev
->curr_resync
,
2949 else for (i
= 0; i
< conf
->geo
.raid_disks
; i
++) {
2951 raid10_find_virt(conf
, mddev
->curr_resync
, i
);
2952 bitmap_end_sync(mddev
->bitmap
, sect
,
2956 /* completed sync */
2957 if ((!mddev
->bitmap
|| conf
->fullsync
)
2958 && conf
->have_replacement
2959 && test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
)) {
2960 /* Completed a full sync so the replacements
2961 * are now fully recovered.
2963 for (i
= 0; i
< conf
->geo
.raid_disks
; i
++)
2964 if (conf
->mirrors
[i
].replacement
)
2965 conf
->mirrors
[i
].replacement
2971 bitmap_close_sync(mddev
->bitmap
);
2974 return sectors_skipped
;
2977 if (test_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
))
2978 return reshape_request(mddev
, sector_nr
, skipped
);
2980 if (chunks_skipped
>= conf
->geo
.raid_disks
) {
2981 /* if there has been nothing to do on any drive,
2982 * then there is nothing to do at all..
2985 return (max_sector
- sector_nr
) + sectors_skipped
;
2988 if (max_sector
> mddev
->resync_max
)
2989 max_sector
= mddev
->resync_max
; /* Don't do IO beyond here */
2991 /* make sure whole request will fit in a chunk - if chunks
2994 if (conf
->geo
.near_copies
< conf
->geo
.raid_disks
&&
2995 max_sector
> (sector_nr
| chunk_mask
))
2996 max_sector
= (sector_nr
| chunk_mask
) + 1;
2998 /* Again, very different code for resync and recovery.
2999 * Both must result in an r10bio with a list of bios that
3000 * have bi_end_io, bi_sector, bi_bdev set,
3001 * and bi_private set to the r10bio.
3002 * For recovery, we may actually create several r10bios
3003 * with 2 bios in each, that correspond to the bios in the main one.
3004 * In this case, the subordinate r10bios link back through a
3005 * borrowed master_bio pointer, and the counter in the master
3006 * includes a ref from each subordinate.
3008 /* First, we decide what to do and set ->bi_end_io
3009 * To end_sync_read if we want to read, and
3010 * end_sync_write if we will want to write.
3013 max_sync
= RESYNC_PAGES
<< (PAGE_SHIFT
-9);
3014 if (!test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
)) {
3015 /* recovery... the complicated one */
3019 for (i
= 0 ; i
< conf
->geo
.raid_disks
; i
++) {
3025 struct raid10_info
*mirror
= &conf
->mirrors
[i
];
3027 if ((mirror
->rdev
== NULL
||
3028 test_bit(In_sync
, &mirror
->rdev
->flags
))
3030 (mirror
->replacement
== NULL
||
3032 &mirror
->replacement
->flags
)))
3036 /* want to reconstruct this device */
3038 sect
= raid10_find_virt(conf
, sector_nr
, i
);
3039 if (sect
>= mddev
->resync_max_sectors
) {
3040 /* last stripe is not complete - don't
3041 * try to recover this sector.
3045 /* Unless we are doing a full sync, or a replacement
3046 * we only need to recover the block if it is set in
3049 must_sync
= bitmap_start_sync(mddev
->bitmap
, sect
,
3051 if (sync_blocks
< max_sync
)
3052 max_sync
= sync_blocks
;
3054 mirror
->replacement
== NULL
&&
3056 /* yep, skip the sync_blocks here, but don't assume
3057 * that there will never be anything to do here
3059 chunks_skipped
= -1;
3063 r10_bio
= mempool_alloc(conf
->r10buf_pool
, GFP_NOIO
);
3065 raise_barrier(conf
, rb2
!= NULL
);
3066 atomic_set(&r10_bio
->remaining
, 0);
3068 r10_bio
->master_bio
= (struct bio
*)rb2
;
3070 atomic_inc(&rb2
->remaining
);
3071 r10_bio
->mddev
= mddev
;
3072 set_bit(R10BIO_IsRecover
, &r10_bio
->state
);
3073 r10_bio
->sector
= sect
;
3075 raid10_find_phys(conf
, r10_bio
);
3077 /* Need to check if the array will still be
3080 for (j
= 0; j
< conf
->geo
.raid_disks
; j
++)
3081 if (conf
->mirrors
[j
].rdev
== NULL
||
3082 test_bit(Faulty
, &conf
->mirrors
[j
].rdev
->flags
)) {
3087 must_sync
= bitmap_start_sync(mddev
->bitmap
, sect
,
3088 &sync_blocks
, still_degraded
);
3091 for (j
=0; j
<conf
->copies
;j
++) {
3093 int d
= r10_bio
->devs
[j
].devnum
;
3094 sector_t from_addr
, to_addr
;
3095 struct md_rdev
*rdev
;
3096 sector_t sector
, first_bad
;
3098 if (!conf
->mirrors
[d
].rdev
||
3099 !test_bit(In_sync
, &conf
->mirrors
[d
].rdev
->flags
))
3101 /* This is where we read from */
3103 rdev
= conf
->mirrors
[d
].rdev
;
3104 sector
= r10_bio
->devs
[j
].addr
;
3106 if (is_badblock(rdev
, sector
, max_sync
,
3107 &first_bad
, &bad_sectors
)) {
3108 if (first_bad
> sector
)
3109 max_sync
= first_bad
- sector
;
3111 bad_sectors
-= (sector
3113 if (max_sync
> bad_sectors
)
3114 max_sync
= bad_sectors
;
3118 bio
= r10_bio
->devs
[0].bio
;
3120 bio
->bi_next
= biolist
;
3122 bio
->bi_private
= r10_bio
;
3123 bio
->bi_end_io
= end_sync_read
;
3125 from_addr
= r10_bio
->devs
[j
].addr
;
3126 bio
->bi_iter
.bi_sector
= from_addr
+
3128 bio
->bi_bdev
= rdev
->bdev
;
3129 atomic_inc(&rdev
->nr_pending
);
3130 /* and we write to 'i' (if not in_sync) */
3132 for (k
=0; k
<conf
->copies
; k
++)
3133 if (r10_bio
->devs
[k
].devnum
== i
)
3135 BUG_ON(k
== conf
->copies
);
3136 to_addr
= r10_bio
->devs
[k
].addr
;
3137 r10_bio
->devs
[0].devnum
= d
;
3138 r10_bio
->devs
[0].addr
= from_addr
;
3139 r10_bio
->devs
[1].devnum
= i
;
3140 r10_bio
->devs
[1].addr
= to_addr
;
3142 rdev
= mirror
->rdev
;
3143 if (!test_bit(In_sync
, &rdev
->flags
)) {
3144 bio
= r10_bio
->devs
[1].bio
;
3146 bio
->bi_next
= biolist
;
3148 bio
->bi_private
= r10_bio
;
3149 bio
->bi_end_io
= end_sync_write
;
3151 bio
->bi_iter
.bi_sector
= to_addr
3152 + rdev
->data_offset
;
3153 bio
->bi_bdev
= rdev
->bdev
;
3154 atomic_inc(&r10_bio
->remaining
);
3156 r10_bio
->devs
[1].bio
->bi_end_io
= NULL
;
3158 /* and maybe write to replacement */
3159 bio
= r10_bio
->devs
[1].repl_bio
;
3161 bio
->bi_end_io
= NULL
;
3162 rdev
= mirror
->replacement
;
3163 /* Note: if rdev != NULL, then bio
3164 * cannot be NULL as r10buf_pool_alloc will
3165 * have allocated it.
3166 * So the second test here is pointless.
3167 * But it keeps semantic-checkers happy, and
3168 * this comment keeps human reviewers
3171 if (rdev
== NULL
|| bio
== NULL
||
3172 test_bit(Faulty
, &rdev
->flags
))
3175 bio
->bi_next
= biolist
;
3177 bio
->bi_private
= r10_bio
;
3178 bio
->bi_end_io
= end_sync_write
;
3180 bio
->bi_iter
.bi_sector
= to_addr
+
3182 bio
->bi_bdev
= rdev
->bdev
;
3183 atomic_inc(&r10_bio
->remaining
);
3186 if (j
== conf
->copies
) {
3187 /* Cannot recover, so abort the recovery or
3188 * record a bad block */
3190 /* problem is that there are bad blocks
3191 * on other device(s)
3194 for (k
= 0; k
< conf
->copies
; k
++)
3195 if (r10_bio
->devs
[k
].devnum
== i
)
3197 if (!test_bit(In_sync
,
3198 &mirror
->rdev
->flags
)
3199 && !rdev_set_badblocks(
3201 r10_bio
->devs
[k
].addr
,
3204 if (mirror
->replacement
&&
3205 !rdev_set_badblocks(
3206 mirror
->replacement
,
3207 r10_bio
->devs
[k
].addr
,
3212 if (!test_and_set_bit(MD_RECOVERY_INTR
,
3214 printk(KERN_INFO
"md/raid10:%s: insufficient "
3215 "working devices for recovery.\n",
3217 mirror
->recovery_disabled
3218 = mddev
->recovery_disabled
;
3222 atomic_dec(&rb2
->remaining
);
3227 if (biolist
== NULL
) {
3229 struct r10bio
*rb2
= r10_bio
;
3230 r10_bio
= (struct r10bio
*) rb2
->master_bio
;
3231 rb2
->master_bio
= NULL
;
3237 /* resync. Schedule a read for every block at this virt offset */
3240 bitmap_cond_end_sync(mddev
->bitmap
, sector_nr
);
3242 if (!bitmap_start_sync(mddev
->bitmap
, sector_nr
,
3243 &sync_blocks
, mddev
->degraded
) &&
3244 !conf
->fullsync
&& !test_bit(MD_RECOVERY_REQUESTED
,
3245 &mddev
->recovery
)) {
3246 /* We can skip this block */
3248 return sync_blocks
+ sectors_skipped
;
3250 if (sync_blocks
< max_sync
)
3251 max_sync
= sync_blocks
;
3252 r10_bio
= mempool_alloc(conf
->r10buf_pool
, GFP_NOIO
);
3255 r10_bio
->mddev
= mddev
;
3256 atomic_set(&r10_bio
->remaining
, 0);
3257 raise_barrier(conf
, 0);
3258 conf
->next_resync
= sector_nr
;
3260 r10_bio
->master_bio
= NULL
;
3261 r10_bio
->sector
= sector_nr
;
3262 set_bit(R10BIO_IsSync
, &r10_bio
->state
);
3263 raid10_find_phys(conf
, r10_bio
);
3264 r10_bio
->sectors
= (sector_nr
| chunk_mask
) - sector_nr
+ 1;
3266 for (i
= 0; i
< conf
->copies
; i
++) {
3267 int d
= r10_bio
->devs
[i
].devnum
;
3268 sector_t first_bad
, sector
;
3271 if (r10_bio
->devs
[i
].repl_bio
)
3272 r10_bio
->devs
[i
].repl_bio
->bi_end_io
= NULL
;
3274 bio
= r10_bio
->devs
[i
].bio
;
3276 clear_bit(BIO_UPTODATE
, &bio
->bi_flags
);
3277 if (conf
->mirrors
[d
].rdev
== NULL
||
3278 test_bit(Faulty
, &conf
->mirrors
[d
].rdev
->flags
))
3280 sector
= r10_bio
->devs
[i
].addr
;
3281 if (is_badblock(conf
->mirrors
[d
].rdev
,
3283 &first_bad
, &bad_sectors
)) {
3284 if (first_bad
> sector
)
3285 max_sync
= first_bad
- sector
;
3287 bad_sectors
-= (sector
- first_bad
);
3288 if (max_sync
> bad_sectors
)
3289 max_sync
= bad_sectors
;
3293 atomic_inc(&conf
->mirrors
[d
].rdev
->nr_pending
);
3294 atomic_inc(&r10_bio
->remaining
);
3295 bio
->bi_next
= biolist
;
3297 bio
->bi_private
= r10_bio
;
3298 bio
->bi_end_io
= end_sync_read
;
3300 bio
->bi_iter
.bi_sector
= sector
+
3301 conf
->mirrors
[d
].rdev
->data_offset
;
3302 bio
->bi_bdev
= conf
->mirrors
[d
].rdev
->bdev
;
3305 if (conf
->mirrors
[d
].replacement
== NULL
||
3307 &conf
->mirrors
[d
].replacement
->flags
))
3310 /* Need to set up for writing to the replacement */
3311 bio
= r10_bio
->devs
[i
].repl_bio
;
3313 clear_bit(BIO_UPTODATE
, &bio
->bi_flags
);
3315 sector
= r10_bio
->devs
[i
].addr
;
3316 atomic_inc(&conf
->mirrors
[d
].rdev
->nr_pending
);
3317 bio
->bi_next
= biolist
;
3319 bio
->bi_private
= r10_bio
;
3320 bio
->bi_end_io
= end_sync_write
;
3322 bio
->bi_iter
.bi_sector
= sector
+
3323 conf
->mirrors
[d
].replacement
->data_offset
;
3324 bio
->bi_bdev
= conf
->mirrors
[d
].replacement
->bdev
;
3329 for (i
=0; i
<conf
->copies
; i
++) {
3330 int d
= r10_bio
->devs
[i
].devnum
;
3331 if (r10_bio
->devs
[i
].bio
->bi_end_io
)
3332 rdev_dec_pending(conf
->mirrors
[d
].rdev
,
3334 if (r10_bio
->devs
[i
].repl_bio
&&
3335 r10_bio
->devs
[i
].repl_bio
->bi_end_io
)
3337 conf
->mirrors
[d
].replacement
,
3347 if (sector_nr
+ max_sync
< max_sector
)
3348 max_sector
= sector_nr
+ max_sync
;
3351 int len
= PAGE_SIZE
;
3352 if (sector_nr
+ (len
>>9) > max_sector
)
3353 len
= (max_sector
- sector_nr
) << 9;
3356 for (bio
= biolist
; bio
; bio
=bio
->bi_next
) {
3358 page
= bio
->bi_io_vec
[bio
->bi_vcnt
].bv_page
;
3359 if (bio_add_page(bio
, page
, len
, 0))
3363 bio
->bi_io_vec
[bio
->bi_vcnt
].bv_page
= page
;
3364 for (bio2
= biolist
;
3365 bio2
&& bio2
!= bio
;
3366 bio2
= bio2
->bi_next
) {
3367 /* remove last page from this bio */
3369 bio2
->bi_iter
.bi_size
-= len
;
3370 __clear_bit(BIO_SEG_VALID
, &bio2
->bi_flags
);
3374 nr_sectors
+= len
>>9;
3375 sector_nr
+= len
>>9;
3376 } while (biolist
->bi_vcnt
< RESYNC_PAGES
);
3378 r10_bio
->sectors
= nr_sectors
;
3382 biolist
= biolist
->bi_next
;
3384 bio
->bi_next
= NULL
;
3385 r10_bio
= bio
->bi_private
;
3386 r10_bio
->sectors
= nr_sectors
;
3388 if (bio
->bi_end_io
== end_sync_read
) {
3389 md_sync_acct(bio
->bi_bdev
, nr_sectors
);
3390 set_bit(BIO_UPTODATE
, &bio
->bi_flags
);
3391 generic_make_request(bio
);
3395 if (sectors_skipped
)
3396 /* pretend they weren't skipped, it makes
3397 * no important difference in this case
3399 md_done_sync(mddev
, sectors_skipped
, 1);
3401 return sectors_skipped
+ nr_sectors
;
3403 /* There is nowhere to write, so all non-sync
3404 * drives must be failed or in resync, all drives
3405 * have a bad block, so try the next chunk...
3407 if (sector_nr
+ max_sync
< max_sector
)
3408 max_sector
= sector_nr
+ max_sync
;
3410 sectors_skipped
+= (max_sector
- sector_nr
);
3412 sector_nr
= max_sector
;
3417 raid10_size(struct mddev
*mddev
, sector_t sectors
, int raid_disks
)
3420 struct r10conf
*conf
= mddev
->private;
3423 raid_disks
= min(conf
->geo
.raid_disks
,
3424 conf
->prev
.raid_disks
);
3426 sectors
= conf
->dev_sectors
;
3428 size
= sectors
>> conf
->geo
.chunk_shift
;
3429 sector_div(size
, conf
->geo
.far_copies
);
3430 size
= size
* raid_disks
;
3431 sector_div(size
, conf
->geo
.near_copies
);
3433 return size
<< conf
->geo
.chunk_shift
;
3436 static void calc_sectors(struct r10conf
*conf
, sector_t size
)
3438 /* Calculate the number of sectors-per-device that will
3439 * actually be used, and set conf->dev_sectors and
3443 size
= size
>> conf
->geo
.chunk_shift
;
3444 sector_div(size
, conf
->geo
.far_copies
);
3445 size
= size
* conf
->geo
.raid_disks
;
3446 sector_div(size
, conf
->geo
.near_copies
);
3447 /* 'size' is now the number of chunks in the array */
3448 /* calculate "used chunks per device" */
3449 size
= size
* conf
->copies
;
3451 /* We need to round up when dividing by raid_disks to
3452 * get the stride size.
3454 size
= DIV_ROUND_UP_SECTOR_T(size
, conf
->geo
.raid_disks
);
3456 conf
->dev_sectors
= size
<< conf
->geo
.chunk_shift
;
3458 if (conf
->geo
.far_offset
)
3459 conf
->geo
.stride
= 1 << conf
->geo
.chunk_shift
;
3461 sector_div(size
, conf
->geo
.far_copies
);
3462 conf
->geo
.stride
= size
<< conf
->geo
.chunk_shift
;
3466 enum geo_type
{geo_new
, geo_old
, geo_start
};
3467 static int setup_geo(struct geom
*geo
, struct mddev
*mddev
, enum geo_type
new)
3470 int layout
, chunk
, disks
;
3473 layout
= mddev
->layout
;
3474 chunk
= mddev
->chunk_sectors
;
3475 disks
= mddev
->raid_disks
- mddev
->delta_disks
;
3478 layout
= mddev
->new_layout
;
3479 chunk
= mddev
->new_chunk_sectors
;
3480 disks
= mddev
->raid_disks
;
3482 default: /* avoid 'may be unused' warnings */
3483 case geo_start
: /* new when starting reshape - raid_disks not
3485 layout
= mddev
->new_layout
;
3486 chunk
= mddev
->new_chunk_sectors
;
3487 disks
= mddev
->raid_disks
+ mddev
->delta_disks
;
3492 if (chunk
< (PAGE_SIZE
>> 9) ||
3493 !is_power_of_2(chunk
))
3496 fc
= (layout
>> 8) & 255;
3497 fo
= layout
& (1<<16);
3498 geo
->raid_disks
= disks
;
3499 geo
->near_copies
= nc
;
3500 geo
->far_copies
= fc
;
3501 geo
->far_offset
= fo
;
3502 geo
->far_set_size
= (layout
& (1<<17)) ? disks
/ fc
: disks
;
3503 geo
->chunk_mask
= chunk
- 1;
3504 geo
->chunk_shift
= ffz(~chunk
);
3508 static struct r10conf
*setup_conf(struct mddev
*mddev
)
3510 struct r10conf
*conf
= NULL
;
3515 copies
= setup_geo(&geo
, mddev
, geo_new
);
3518 printk(KERN_ERR
"md/raid10:%s: chunk size must be "
3519 "at least PAGE_SIZE(%ld) and be a power of 2.\n",
3520 mdname(mddev
), PAGE_SIZE
);
3524 if (copies
< 2 || copies
> mddev
->raid_disks
) {
3525 printk(KERN_ERR
"md/raid10:%s: unsupported raid10 layout: 0x%8x\n",
3526 mdname(mddev
), mddev
->new_layout
);
3531 conf
= kzalloc(sizeof(struct r10conf
), GFP_KERNEL
);
3535 /* FIXME calc properly */
3536 conf
->mirrors
= kzalloc(sizeof(struct raid10_info
)*(mddev
->raid_disks
+
3537 max(0,-mddev
->delta_disks
)),
3542 conf
->tmppage
= alloc_page(GFP_KERNEL
);
3547 conf
->copies
= copies
;
3548 conf
->r10bio_pool
= mempool_create(NR_RAID10_BIOS
, r10bio_pool_alloc
,
3549 r10bio_pool_free
, conf
);
3550 if (!conf
->r10bio_pool
)
3553 calc_sectors(conf
, mddev
->dev_sectors
);
3554 if (mddev
->reshape_position
== MaxSector
) {
3555 conf
->prev
= conf
->geo
;
3556 conf
->reshape_progress
= MaxSector
;
3558 if (setup_geo(&conf
->prev
, mddev
, geo_old
) != conf
->copies
) {
3562 conf
->reshape_progress
= mddev
->reshape_position
;
3563 if (conf
->prev
.far_offset
)
3564 conf
->prev
.stride
= 1 << conf
->prev
.chunk_shift
;
3566 /* far_copies must be 1 */
3567 conf
->prev
.stride
= conf
->dev_sectors
;
3569 spin_lock_init(&conf
->device_lock
);
3570 INIT_LIST_HEAD(&conf
->retry_list
);
3572 spin_lock_init(&conf
->resync_lock
);
3573 init_waitqueue_head(&conf
->wait_barrier
);
3575 conf
->thread
= md_register_thread(raid10d
, mddev
, "raid10");
3579 conf
->mddev
= mddev
;
3584 printk(KERN_ERR
"md/raid10:%s: couldn't allocate memory.\n",
3587 if (conf
->r10bio_pool
)
3588 mempool_destroy(conf
->r10bio_pool
);
3589 kfree(conf
->mirrors
);
3590 safe_put_page(conf
->tmppage
);
3593 return ERR_PTR(err
);
3596 static int run(struct mddev
*mddev
)
3598 struct r10conf
*conf
;
3599 int i
, disk_idx
, chunk_size
;
3600 struct raid10_info
*disk
;
3601 struct md_rdev
*rdev
;
3603 sector_t min_offset_diff
= 0;
3605 bool discard_supported
= false;
3607 if (mddev
->private == NULL
) {
3608 conf
= setup_conf(mddev
);
3610 return PTR_ERR(conf
);
3611 mddev
->private = conf
;
3613 conf
= mddev
->private;
3617 mddev
->thread
= conf
->thread
;
3618 conf
->thread
= NULL
;
3620 chunk_size
= mddev
->chunk_sectors
<< 9;
3622 blk_queue_max_discard_sectors(mddev
->queue
,
3623 mddev
->chunk_sectors
);
3624 blk_queue_max_write_same_sectors(mddev
->queue
, 0);
3625 blk_queue_io_min(mddev
->queue
, chunk_size
);
3626 if (conf
->geo
.raid_disks
% conf
->geo
.near_copies
)
3627 blk_queue_io_opt(mddev
->queue
, chunk_size
* conf
->geo
.raid_disks
);
3629 blk_queue_io_opt(mddev
->queue
, chunk_size
*
3630 (conf
->geo
.raid_disks
/ conf
->geo
.near_copies
));
3633 rdev_for_each(rdev
, mddev
) {
3635 struct request_queue
*q
;
3637 disk_idx
= rdev
->raid_disk
;
3640 if (disk_idx
>= conf
->geo
.raid_disks
&&
3641 disk_idx
>= conf
->prev
.raid_disks
)
3643 disk
= conf
->mirrors
+ disk_idx
;
3645 if (test_bit(Replacement
, &rdev
->flags
)) {
3646 if (disk
->replacement
)
3648 disk
->replacement
= rdev
;
3654 q
= bdev_get_queue(rdev
->bdev
);
3655 if (q
->merge_bvec_fn
)
3656 mddev
->merge_check_needed
= 1;
3657 diff
= (rdev
->new_data_offset
- rdev
->data_offset
);
3658 if (!mddev
->reshape_backwards
)
3662 if (first
|| diff
< min_offset_diff
)
3663 min_offset_diff
= diff
;
3666 disk_stack_limits(mddev
->gendisk
, rdev
->bdev
,
3667 rdev
->data_offset
<< 9);
3669 disk
->head_position
= 0;
3671 if (blk_queue_discard(bdev_get_queue(rdev
->bdev
)))
3672 discard_supported
= true;
3676 if (discard_supported
)
3677 queue_flag_set_unlocked(QUEUE_FLAG_DISCARD
,
3680 queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD
,
3683 /* need to check that every block has at least one working mirror */
3684 if (!enough(conf
, -1)) {
3685 printk(KERN_ERR
"md/raid10:%s: not enough operational mirrors.\n",
3690 if (conf
->reshape_progress
!= MaxSector
) {
3691 /* must ensure that shape change is supported */
3692 if (conf
->geo
.far_copies
!= 1 &&
3693 conf
->geo
.far_offset
== 0)
3695 if (conf
->prev
.far_copies
!= 1 &&
3696 conf
->prev
.far_offset
== 0)
3700 mddev
->degraded
= 0;
3702 i
< conf
->geo
.raid_disks
3703 || i
< conf
->prev
.raid_disks
;
3706 disk
= conf
->mirrors
+ i
;
3708 if (!disk
->rdev
&& disk
->replacement
) {
3709 /* The replacement is all we have - use it */
3710 disk
->rdev
= disk
->replacement
;
3711 disk
->replacement
= NULL
;
3712 clear_bit(Replacement
, &disk
->rdev
->flags
);
3716 !test_bit(In_sync
, &disk
->rdev
->flags
)) {
3717 disk
->head_position
= 0;
3720 disk
->rdev
->saved_raid_disk
< 0)
3723 disk
->recovery_disabled
= mddev
->recovery_disabled
- 1;
3726 if (mddev
->recovery_cp
!= MaxSector
)
3727 printk(KERN_NOTICE
"md/raid10:%s: not clean"
3728 " -- starting background reconstruction\n",
3731 "md/raid10:%s: active with %d out of %d devices\n",
3732 mdname(mddev
), conf
->geo
.raid_disks
- mddev
->degraded
,
3733 conf
->geo
.raid_disks
);
3735 * Ok, everything is just fine now
3737 mddev
->dev_sectors
= conf
->dev_sectors
;
3738 size
= raid10_size(mddev
, 0, 0);
3739 md_set_array_sectors(mddev
, size
);
3740 mddev
->resync_max_sectors
= size
;
3743 int stripe
= conf
->geo
.raid_disks
*
3744 ((mddev
->chunk_sectors
<< 9) / PAGE_SIZE
);
3746 /* Calculate max read-ahead size.
3747 * We need to readahead at least twice a whole stripe....
3750 stripe
/= conf
->geo
.near_copies
;
3751 if (mddev
->queue
->backing_dev_info
.ra_pages
< 2 * stripe
)
3752 mddev
->queue
->backing_dev_info
.ra_pages
= 2 * stripe
;
3755 if (md_integrity_register(mddev
))
3758 if (conf
->reshape_progress
!= MaxSector
) {
3759 unsigned long before_length
, after_length
;
3761 before_length
= ((1 << conf
->prev
.chunk_shift
) *
3762 conf
->prev
.far_copies
);
3763 after_length
= ((1 << conf
->geo
.chunk_shift
) *
3764 conf
->geo
.far_copies
);
3766 if (max(before_length
, after_length
) > min_offset_diff
) {
3767 /* This cannot work */
3768 printk("md/raid10: offset difference not enough to continue reshape\n");
3771 conf
->offset_diff
= min_offset_diff
;
3773 conf
->reshape_safe
= conf
->reshape_progress
;
3774 clear_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
);
3775 clear_bit(MD_RECOVERY_CHECK
, &mddev
->recovery
);
3776 set_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
);
3777 set_bit(MD_RECOVERY_RUNNING
, &mddev
->recovery
);
3778 mddev
->sync_thread
= md_register_thread(md_do_sync
, mddev
,
3785 md_unregister_thread(&mddev
->thread
);
3786 if (conf
->r10bio_pool
)
3787 mempool_destroy(conf
->r10bio_pool
);
3788 safe_put_page(conf
->tmppage
);
3789 kfree(conf
->mirrors
);
3791 mddev
->private = NULL
;
3796 static void raid10_free(struct mddev
*mddev
, void *priv
)
3798 struct r10conf
*conf
= priv
;
3800 if (conf
->r10bio_pool
)
3801 mempool_destroy(conf
->r10bio_pool
);
3802 safe_put_page(conf
->tmppage
);
3803 kfree(conf
->mirrors
);
3804 kfree(conf
->mirrors_old
);
3805 kfree(conf
->mirrors_new
);
3809 static void raid10_quiesce(struct mddev
*mddev
, int state
)
3811 struct r10conf
*conf
= mddev
->private;
3815 raise_barrier(conf
, 0);
3818 lower_barrier(conf
);
3823 static int raid10_resize(struct mddev
*mddev
, sector_t sectors
)
3825 /* Resize of 'far' arrays is not supported.
3826 * For 'near' and 'offset' arrays we can set the
3827 * number of sectors used to be an appropriate multiple
3828 * of the chunk size.
3829 * For 'offset', this is far_copies*chunksize.
3830 * For 'near' the multiplier is the LCM of
3831 * near_copies and raid_disks.
3832 * So if far_copies > 1 && !far_offset, fail.
3833 * Else find LCM(raid_disks, near_copy)*far_copies and
3834 * multiply by chunk_size. Then round to this number.
3835 * This is mostly done by raid10_size()
3837 struct r10conf
*conf
= mddev
->private;
3838 sector_t oldsize
, size
;
3840 if (mddev
->reshape_position
!= MaxSector
)
3843 if (conf
->geo
.far_copies
> 1 && !conf
->geo
.far_offset
)
3846 oldsize
= raid10_size(mddev
, 0, 0);
3847 size
= raid10_size(mddev
, sectors
, 0);
3848 if (mddev
->external_size
&&
3849 mddev
->array_sectors
> size
)
3851 if (mddev
->bitmap
) {
3852 int ret
= bitmap_resize(mddev
->bitmap
, size
, 0, 0);
3856 md_set_array_sectors(mddev
, size
);
3857 set_capacity(mddev
->gendisk
, mddev
->array_sectors
);
3858 revalidate_disk(mddev
->gendisk
);
3859 if (sectors
> mddev
->dev_sectors
&&
3860 mddev
->recovery_cp
> oldsize
) {
3861 mddev
->recovery_cp
= oldsize
;
3862 set_bit(MD_RECOVERY_NEEDED
, &mddev
->recovery
);
3864 calc_sectors(conf
, sectors
);
3865 mddev
->dev_sectors
= conf
->dev_sectors
;
3866 mddev
->resync_max_sectors
= size
;
3870 static void *raid10_takeover_raid0(struct mddev
*mddev
, sector_t size
, int devs
)
3872 struct md_rdev
*rdev
;
3873 struct r10conf
*conf
;
3875 if (mddev
->degraded
> 0) {
3876 printk(KERN_ERR
"md/raid10:%s: Error: degraded raid0!\n",
3878 return ERR_PTR(-EINVAL
);
3880 sector_div(size
, devs
);
3882 /* Set new parameters */
3883 mddev
->new_level
= 10;
3884 /* new layout: far_copies = 1, near_copies = 2 */
3885 mddev
->new_layout
= (1<<8) + 2;
3886 mddev
->new_chunk_sectors
= mddev
->chunk_sectors
;
3887 mddev
->delta_disks
= mddev
->raid_disks
;
3888 mddev
->raid_disks
*= 2;
3889 /* make sure it will be not marked as dirty */
3890 mddev
->recovery_cp
= MaxSector
;
3891 mddev
->dev_sectors
= size
;
3893 conf
= setup_conf(mddev
);
3894 if (!IS_ERR(conf
)) {
3895 rdev_for_each(rdev
, mddev
)
3896 if (rdev
->raid_disk
>= 0) {
3897 rdev
->new_raid_disk
= rdev
->raid_disk
* 2;
3898 rdev
->sectors
= size
;
3906 static void *raid10_takeover(struct mddev
*mddev
)
3908 struct r0conf
*raid0_conf
;
3910 /* raid10 can take over:
3911 * raid0 - providing it has only two drives
3913 if (mddev
->level
== 0) {
3914 /* for raid0 takeover only one zone is supported */
3915 raid0_conf
= mddev
->private;
3916 if (raid0_conf
->nr_strip_zones
> 1) {
3917 printk(KERN_ERR
"md/raid10:%s: cannot takeover raid 0"
3918 " with more than one zone.\n",
3920 return ERR_PTR(-EINVAL
);
3922 return raid10_takeover_raid0(mddev
,
3923 raid0_conf
->strip_zone
->zone_end
,
3924 raid0_conf
->strip_zone
->nb_dev
);
3926 return ERR_PTR(-EINVAL
);
3929 static int raid10_check_reshape(struct mddev
*mddev
)
3931 /* Called when there is a request to change
3932 * - layout (to ->new_layout)
3933 * - chunk size (to ->new_chunk_sectors)
3934 * - raid_disks (by delta_disks)
3935 * or when trying to restart a reshape that was ongoing.
3937 * We need to validate the request and possibly allocate
3938 * space if that might be an issue later.
3940 * Currently we reject any reshape of a 'far' mode array,
3941 * allow chunk size to change if new is generally acceptable,
3942 * allow raid_disks to increase, and allow
3943 * a switch between 'near' mode and 'offset' mode.
3945 struct r10conf
*conf
= mddev
->private;
3948 if (conf
->geo
.far_copies
!= 1 && !conf
->geo
.far_offset
)
3951 if (setup_geo(&geo
, mddev
, geo_start
) != conf
->copies
)
3952 /* mustn't change number of copies */
3954 if (geo
.far_copies
> 1 && !geo
.far_offset
)
3955 /* Cannot switch to 'far' mode */
3958 if (mddev
->array_sectors
& geo
.chunk_mask
)
3959 /* not factor of array size */
3962 if (!enough(conf
, -1))
3965 kfree(conf
->mirrors_new
);
3966 conf
->mirrors_new
= NULL
;
3967 if (mddev
->delta_disks
> 0) {
3968 /* allocate new 'mirrors' list */
3969 conf
->mirrors_new
= kzalloc(
3970 sizeof(struct raid10_info
)
3971 *(mddev
->raid_disks
+
3972 mddev
->delta_disks
),
3974 if (!conf
->mirrors_new
)
3981 * Need to check if array has failed when deciding whether to:
3983 * - remove non-faulty devices
3986 * This determination is simple when no reshape is happening.
3987 * However if there is a reshape, we need to carefully check
3988 * both the before and after sections.
3989 * This is because some failed devices may only affect one
3990 * of the two sections, and some non-in_sync devices may
3991 * be insync in the section most affected by failed devices.
3993 static int calc_degraded(struct r10conf
*conf
)
3995 int degraded
, degraded2
;
4000 /* 'prev' section first */
4001 for (i
= 0; i
< conf
->prev
.raid_disks
; i
++) {
4002 struct md_rdev
*rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
4003 if (!rdev
|| test_bit(Faulty
, &rdev
->flags
))
4005 else if (!test_bit(In_sync
, &rdev
->flags
))
4006 /* When we can reduce the number of devices in
4007 * an array, this might not contribute to
4008 * 'degraded'. It does now.
4013 if (conf
->geo
.raid_disks
== conf
->prev
.raid_disks
)
4017 for (i
= 0; i
< conf
->geo
.raid_disks
; i
++) {
4018 struct md_rdev
*rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
4019 if (!rdev
|| test_bit(Faulty
, &rdev
->flags
))
4021 else if (!test_bit(In_sync
, &rdev
->flags
)) {
4022 /* If reshape is increasing the number of devices,
4023 * this section has already been recovered, so
4024 * it doesn't contribute to degraded.
4027 if (conf
->geo
.raid_disks
<= conf
->prev
.raid_disks
)
4032 if (degraded2
> degraded
)
4037 static int raid10_start_reshape(struct mddev
*mddev
)
4039 /* A 'reshape' has been requested. This commits
4040 * the various 'new' fields and sets MD_RECOVER_RESHAPE
4041 * This also checks if there are enough spares and adds them
4043 * We currently require enough spares to make the final
4044 * array non-degraded. We also require that the difference
4045 * between old and new data_offset - on each device - is
4046 * enough that we never risk over-writing.
4049 unsigned long before_length
, after_length
;
4050 sector_t min_offset_diff
= 0;
4053 struct r10conf
*conf
= mddev
->private;
4054 struct md_rdev
*rdev
;
4058 if (test_bit(MD_RECOVERY_RUNNING
, &mddev
->recovery
))
4061 if (setup_geo(&new, mddev
, geo_start
) != conf
->copies
)
4064 before_length
= ((1 << conf
->prev
.chunk_shift
) *
4065 conf
->prev
.far_copies
);
4066 after_length
= ((1 << conf
->geo
.chunk_shift
) *
4067 conf
->geo
.far_copies
);
4069 rdev_for_each(rdev
, mddev
) {
4070 if (!test_bit(In_sync
, &rdev
->flags
)
4071 && !test_bit(Faulty
, &rdev
->flags
))
4073 if (rdev
->raid_disk
>= 0) {
4074 long long diff
= (rdev
->new_data_offset
4075 - rdev
->data_offset
);
4076 if (!mddev
->reshape_backwards
)
4080 if (first
|| diff
< min_offset_diff
)
4081 min_offset_diff
= diff
;
4085 if (max(before_length
, after_length
) > min_offset_diff
)
4088 if (spares
< mddev
->delta_disks
)
4091 conf
->offset_diff
= min_offset_diff
;
4092 spin_lock_irq(&conf
->device_lock
);
4093 if (conf
->mirrors_new
) {
4094 memcpy(conf
->mirrors_new
, conf
->mirrors
,
4095 sizeof(struct raid10_info
)*conf
->prev
.raid_disks
);
4097 kfree(conf
->mirrors_old
);
4098 conf
->mirrors_old
= conf
->mirrors
;
4099 conf
->mirrors
= conf
->mirrors_new
;
4100 conf
->mirrors_new
= NULL
;
4102 setup_geo(&conf
->geo
, mddev
, geo_start
);
4104 if (mddev
->reshape_backwards
) {
4105 sector_t size
= raid10_size(mddev
, 0, 0);
4106 if (size
< mddev
->array_sectors
) {
4107 spin_unlock_irq(&conf
->device_lock
);
4108 printk(KERN_ERR
"md/raid10:%s: array size must be reduce before number of disks\n",
4112 mddev
->resync_max_sectors
= size
;
4113 conf
->reshape_progress
= size
;
4115 conf
->reshape_progress
= 0;
4116 spin_unlock_irq(&conf
->device_lock
);
4118 if (mddev
->delta_disks
&& mddev
->bitmap
) {
4119 ret
= bitmap_resize(mddev
->bitmap
,
4120 raid10_size(mddev
, 0,
4121 conf
->geo
.raid_disks
),
4126 if (mddev
->delta_disks
> 0) {
4127 rdev_for_each(rdev
, mddev
)
4128 if (rdev
->raid_disk
< 0 &&
4129 !test_bit(Faulty
, &rdev
->flags
)) {
4130 if (raid10_add_disk(mddev
, rdev
) == 0) {
4131 if (rdev
->raid_disk
>=
4132 conf
->prev
.raid_disks
)
4133 set_bit(In_sync
, &rdev
->flags
);
4135 rdev
->recovery_offset
= 0;
4137 if (sysfs_link_rdev(mddev
, rdev
))
4138 /* Failure here is OK */;
4140 } else if (rdev
->raid_disk
>= conf
->prev
.raid_disks
4141 && !test_bit(Faulty
, &rdev
->flags
)) {
4142 /* This is a spare that was manually added */
4143 set_bit(In_sync
, &rdev
->flags
);
4146 /* When a reshape changes the number of devices,
4147 * ->degraded is measured against the larger of the
4148 * pre and post numbers.
4150 spin_lock_irq(&conf
->device_lock
);
4151 mddev
->degraded
= calc_degraded(conf
);
4152 spin_unlock_irq(&conf
->device_lock
);
4153 mddev
->raid_disks
= conf
->geo
.raid_disks
;
4154 mddev
->reshape_position
= conf
->reshape_progress
;
4155 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
4157 clear_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
);
4158 clear_bit(MD_RECOVERY_CHECK
, &mddev
->recovery
);
4159 set_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
);
4160 set_bit(MD_RECOVERY_RUNNING
, &mddev
->recovery
);
4162 mddev
->sync_thread
= md_register_thread(md_do_sync
, mddev
,
4164 if (!mddev
->sync_thread
) {
4168 conf
->reshape_checkpoint
= jiffies
;
4169 md_wakeup_thread(mddev
->sync_thread
);
4170 md_new_event(mddev
);
4174 mddev
->recovery
= 0;
4175 spin_lock_irq(&conf
->device_lock
);
4176 conf
->geo
= conf
->prev
;
4177 mddev
->raid_disks
= conf
->geo
.raid_disks
;
4178 rdev_for_each(rdev
, mddev
)
4179 rdev
->new_data_offset
= rdev
->data_offset
;
4181 conf
->reshape_progress
= MaxSector
;
4182 mddev
->reshape_position
= MaxSector
;
4183 spin_unlock_irq(&conf
->device_lock
);
4187 /* Calculate the last device-address that could contain
4188 * any block from the chunk that includes the array-address 's'
4189 * and report the next address.
4190 * i.e. the address returned will be chunk-aligned and after
4191 * any data that is in the chunk containing 's'.
4193 static sector_t
last_dev_address(sector_t s
, struct geom
*geo
)
4195 s
= (s
| geo
->chunk_mask
) + 1;
4196 s
>>= geo
->chunk_shift
;
4197 s
*= geo
->near_copies
;
4198 s
= DIV_ROUND_UP_SECTOR_T(s
, geo
->raid_disks
);
4199 s
*= geo
->far_copies
;
4200 s
<<= geo
->chunk_shift
;
4204 /* Calculate the first device-address that could contain
4205 * any block from the chunk that includes the array-address 's'.
4206 * This too will be the start of a chunk
4208 static sector_t
first_dev_address(sector_t s
, struct geom
*geo
)
4210 s
>>= geo
->chunk_shift
;
4211 s
*= geo
->near_copies
;
4212 sector_div(s
, geo
->raid_disks
);
4213 s
*= geo
->far_copies
;
4214 s
<<= geo
->chunk_shift
;
4218 static sector_t
reshape_request(struct mddev
*mddev
, sector_t sector_nr
,
4221 /* We simply copy at most one chunk (smallest of old and new)
4222 * at a time, possibly less if that exceeds RESYNC_PAGES,
4223 * or we hit a bad block or something.
4224 * This might mean we pause for normal IO in the middle of
4225 * a chunk, but that is not a problem was mddev->reshape_position
4226 * can record any location.
4228 * If we will want to write to a location that isn't
4229 * yet recorded as 'safe' (i.e. in metadata on disk) then
4230 * we need to flush all reshape requests and update the metadata.
4232 * When reshaping forwards (e.g. to more devices), we interpret
4233 * 'safe' as the earliest block which might not have been copied
4234 * down yet. We divide this by previous stripe size and multiply
4235 * by previous stripe length to get lowest device offset that we
4236 * cannot write to yet.
4237 * We interpret 'sector_nr' as an address that we want to write to.
4238 * From this we use last_device_address() to find where we might
4239 * write to, and first_device_address on the 'safe' position.
4240 * If this 'next' write position is after the 'safe' position,
4241 * we must update the metadata to increase the 'safe' position.
4243 * When reshaping backwards, we round in the opposite direction
4244 * and perform the reverse test: next write position must not be
4245 * less than current safe position.
4247 * In all this the minimum difference in data offsets
4248 * (conf->offset_diff - always positive) allows a bit of slack,
4249 * so next can be after 'safe', but not by more than offset_disk
4251 * We need to prepare all the bios here before we start any IO
4252 * to ensure the size we choose is acceptable to all devices.
4253 * The means one for each copy for write-out and an extra one for
4255 * We store the read-in bio in ->master_bio and the others in
4256 * ->devs[x].bio and ->devs[x].repl_bio.
4258 struct r10conf
*conf
= mddev
->private;
4259 struct r10bio
*r10_bio
;
4260 sector_t next
, safe
, last
;
4264 struct md_rdev
*rdev
;
4267 struct bio
*bio
, *read_bio
;
4268 int sectors_done
= 0;
4270 if (sector_nr
== 0) {
4271 /* If restarting in the middle, skip the initial sectors */
4272 if (mddev
->reshape_backwards
&&
4273 conf
->reshape_progress
< raid10_size(mddev
, 0, 0)) {
4274 sector_nr
= (raid10_size(mddev
, 0, 0)
4275 - conf
->reshape_progress
);
4276 } else if (!mddev
->reshape_backwards
&&
4277 conf
->reshape_progress
> 0)
4278 sector_nr
= conf
->reshape_progress
;
4280 mddev
->curr_resync_completed
= sector_nr
;
4281 sysfs_notify(&mddev
->kobj
, NULL
, "sync_completed");
4287 /* We don't use sector_nr to track where we are up to
4288 * as that doesn't work well for ->reshape_backwards.
4289 * So just use ->reshape_progress.
4291 if (mddev
->reshape_backwards
) {
4292 /* 'next' is the earliest device address that we might
4293 * write to for this chunk in the new layout
4295 next
= first_dev_address(conf
->reshape_progress
- 1,
4298 /* 'safe' is the last device address that we might read from
4299 * in the old layout after a restart
4301 safe
= last_dev_address(conf
->reshape_safe
- 1,
4304 if (next
+ conf
->offset_diff
< safe
)
4307 last
= conf
->reshape_progress
- 1;
4308 sector_nr
= last
& ~(sector_t
)(conf
->geo
.chunk_mask
4309 & conf
->prev
.chunk_mask
);
4310 if (sector_nr
+ RESYNC_BLOCK_SIZE
/512 < last
)
4311 sector_nr
= last
+ 1 - RESYNC_BLOCK_SIZE
/512;
4313 /* 'next' is after the last device address that we
4314 * might write to for this chunk in the new layout
4316 next
= last_dev_address(conf
->reshape_progress
, &conf
->geo
);
4318 /* 'safe' is the earliest device address that we might
4319 * read from in the old layout after a restart
4321 safe
= first_dev_address(conf
->reshape_safe
, &conf
->prev
);
4323 /* Need to update metadata if 'next' might be beyond 'safe'
4324 * as that would possibly corrupt data
4326 if (next
> safe
+ conf
->offset_diff
)
4329 sector_nr
= conf
->reshape_progress
;
4330 last
= sector_nr
| (conf
->geo
.chunk_mask
4331 & conf
->prev
.chunk_mask
);
4333 if (sector_nr
+ RESYNC_BLOCK_SIZE
/512 <= last
)
4334 last
= sector_nr
+ RESYNC_BLOCK_SIZE
/512 - 1;
4338 time_after(jiffies
, conf
->reshape_checkpoint
+ 10*HZ
)) {
4339 /* Need to update reshape_position in metadata */
4341 mddev
->reshape_position
= conf
->reshape_progress
;
4342 if (mddev
->reshape_backwards
)
4343 mddev
->curr_resync_completed
= raid10_size(mddev
, 0, 0)
4344 - conf
->reshape_progress
;
4346 mddev
->curr_resync_completed
= conf
->reshape_progress
;
4347 conf
->reshape_checkpoint
= jiffies
;
4348 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
4349 md_wakeup_thread(mddev
->thread
);
4350 wait_event(mddev
->sb_wait
, mddev
->flags
== 0 ||
4351 test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
));
4352 if (test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
)) {
4353 allow_barrier(conf
);
4354 return sectors_done
;
4356 conf
->reshape_safe
= mddev
->reshape_position
;
4357 allow_barrier(conf
);
4361 /* Now schedule reads for blocks from sector_nr to last */
4362 r10_bio
= mempool_alloc(conf
->r10buf_pool
, GFP_NOIO
);
4364 raise_barrier(conf
, sectors_done
!= 0);
4365 atomic_set(&r10_bio
->remaining
, 0);
4366 r10_bio
->mddev
= mddev
;
4367 r10_bio
->sector
= sector_nr
;
4368 set_bit(R10BIO_IsReshape
, &r10_bio
->state
);
4369 r10_bio
->sectors
= last
- sector_nr
+ 1;
4370 rdev
= read_balance(conf
, r10_bio
, &max_sectors
);
4371 BUG_ON(!test_bit(R10BIO_Previous
, &r10_bio
->state
));
4374 /* Cannot read from here, so need to record bad blocks
4375 * on all the target devices.
4378 mempool_free(r10_bio
, conf
->r10buf_pool
);
4379 set_bit(MD_RECOVERY_INTR
, &mddev
->recovery
);
4380 return sectors_done
;
4383 read_bio
= bio_alloc_mddev(GFP_KERNEL
, RESYNC_PAGES
, mddev
);
4385 read_bio
->bi_bdev
= rdev
->bdev
;
4386 read_bio
->bi_iter
.bi_sector
= (r10_bio
->devs
[r10_bio
->read_slot
].addr
4387 + rdev
->data_offset
);
4388 read_bio
->bi_private
= r10_bio
;
4389 read_bio
->bi_end_io
= end_sync_read
;
4390 read_bio
->bi_rw
= READ
;
4391 read_bio
->bi_flags
&= (~0UL << BIO_RESET_BITS
);
4392 __set_bit(BIO_UPTODATE
, &read_bio
->bi_flags
);
4393 read_bio
->bi_vcnt
= 0;
4394 read_bio
->bi_iter
.bi_size
= 0;
4395 r10_bio
->master_bio
= read_bio
;
4396 r10_bio
->read_slot
= r10_bio
->devs
[r10_bio
->read_slot
].devnum
;
4398 /* Now find the locations in the new layout */
4399 __raid10_find_phys(&conf
->geo
, r10_bio
);
4402 read_bio
->bi_next
= NULL
;
4404 for (s
= 0; s
< conf
->copies
*2; s
++) {
4406 int d
= r10_bio
->devs
[s
/2].devnum
;
4407 struct md_rdev
*rdev2
;
4409 rdev2
= conf
->mirrors
[d
].replacement
;
4410 b
= r10_bio
->devs
[s
/2].repl_bio
;
4412 rdev2
= conf
->mirrors
[d
].rdev
;
4413 b
= r10_bio
->devs
[s
/2].bio
;
4415 if (!rdev2
|| test_bit(Faulty
, &rdev2
->flags
))
4419 b
->bi_bdev
= rdev2
->bdev
;
4420 b
->bi_iter
.bi_sector
= r10_bio
->devs
[s
/2].addr
+
4421 rdev2
->new_data_offset
;
4422 b
->bi_private
= r10_bio
;
4423 b
->bi_end_io
= end_reshape_write
;
4429 /* Now add as many pages as possible to all of these bios. */
4432 for (s
= 0 ; s
< max_sectors
; s
+= PAGE_SIZE
>> 9) {
4433 struct page
*page
= r10_bio
->devs
[0].bio
->bi_io_vec
[s
/(PAGE_SIZE
>>9)].bv_page
;
4434 int len
= (max_sectors
- s
) << 9;
4435 if (len
> PAGE_SIZE
)
4437 for (bio
= blist
; bio
; bio
= bio
->bi_next
) {
4439 if (bio_add_page(bio
, page
, len
, 0))
4442 /* Didn't fit, must stop */
4444 bio2
&& bio2
!= bio
;
4445 bio2
= bio2
->bi_next
) {
4446 /* Remove last page from this bio */
4448 bio2
->bi_iter
.bi_size
-= len
;
4449 __clear_bit(BIO_SEG_VALID
, &bio2
->bi_flags
);
4453 sector_nr
+= len
>> 9;
4454 nr_sectors
+= len
>> 9;
4457 r10_bio
->sectors
= nr_sectors
;
4459 /* Now submit the read */
4460 md_sync_acct(read_bio
->bi_bdev
, r10_bio
->sectors
);
4461 atomic_inc(&r10_bio
->remaining
);
4462 read_bio
->bi_next
= NULL
;
4463 generic_make_request(read_bio
);
4464 sector_nr
+= nr_sectors
;
4465 sectors_done
+= nr_sectors
;
4466 if (sector_nr
<= last
)
4469 /* Now that we have done the whole section we can
4470 * update reshape_progress
4472 if (mddev
->reshape_backwards
)
4473 conf
->reshape_progress
-= sectors_done
;
4475 conf
->reshape_progress
+= sectors_done
;
4477 return sectors_done
;
4480 static void end_reshape_request(struct r10bio
*r10_bio
);
4481 static int handle_reshape_read_error(struct mddev
*mddev
,
4482 struct r10bio
*r10_bio
);
4483 static void reshape_request_write(struct mddev
*mddev
, struct r10bio
*r10_bio
)
4485 /* Reshape read completed. Hopefully we have a block
4487 * If we got a read error then we do sync 1-page reads from
4488 * elsewhere until we find the data - or give up.
4490 struct r10conf
*conf
= mddev
->private;
4493 if (!test_bit(R10BIO_Uptodate
, &r10_bio
->state
))
4494 if (handle_reshape_read_error(mddev
, r10_bio
) < 0) {
4495 /* Reshape has been aborted */
4496 md_done_sync(mddev
, r10_bio
->sectors
, 0);
4500 /* We definitely have the data in the pages, schedule the
4503 atomic_set(&r10_bio
->remaining
, 1);
4504 for (s
= 0; s
< conf
->copies
*2; s
++) {
4506 int d
= r10_bio
->devs
[s
/2].devnum
;
4507 struct md_rdev
*rdev
;
4509 rdev
= conf
->mirrors
[d
].replacement
;
4510 b
= r10_bio
->devs
[s
/2].repl_bio
;
4512 rdev
= conf
->mirrors
[d
].rdev
;
4513 b
= r10_bio
->devs
[s
/2].bio
;
4515 if (!rdev
|| test_bit(Faulty
, &rdev
->flags
))
4517 atomic_inc(&rdev
->nr_pending
);
4518 md_sync_acct(b
->bi_bdev
, r10_bio
->sectors
);
4519 atomic_inc(&r10_bio
->remaining
);
4521 generic_make_request(b
);
4523 end_reshape_request(r10_bio
);
4526 static void end_reshape(struct r10conf
*conf
)
4528 if (test_bit(MD_RECOVERY_INTR
, &conf
->mddev
->recovery
))
4531 spin_lock_irq(&conf
->device_lock
);
4532 conf
->prev
= conf
->geo
;
4533 md_finish_reshape(conf
->mddev
);
4535 conf
->reshape_progress
= MaxSector
;
4536 spin_unlock_irq(&conf
->device_lock
);
4538 /* read-ahead size must cover two whole stripes, which is
4539 * 2 * (datadisks) * chunksize where 'n' is the number of raid devices
4541 if (conf
->mddev
->queue
) {
4542 int stripe
= conf
->geo
.raid_disks
*
4543 ((conf
->mddev
->chunk_sectors
<< 9) / PAGE_SIZE
);
4544 stripe
/= conf
->geo
.near_copies
;
4545 if (conf
->mddev
->queue
->backing_dev_info
.ra_pages
< 2 * stripe
)
4546 conf
->mddev
->queue
->backing_dev_info
.ra_pages
= 2 * stripe
;
4551 static int handle_reshape_read_error(struct mddev
*mddev
,
4552 struct r10bio
*r10_bio
)
4554 /* Use sync reads to get the blocks from somewhere else */
4555 int sectors
= r10_bio
->sectors
;
4556 struct r10conf
*conf
= mddev
->private;
4558 struct r10bio r10_bio
;
4559 struct r10dev devs
[conf
->copies
];
4561 struct r10bio
*r10b
= &on_stack
.r10_bio
;
4564 struct bio_vec
*bvec
= r10_bio
->master_bio
->bi_io_vec
;
4566 r10b
->sector
= r10_bio
->sector
;
4567 __raid10_find_phys(&conf
->prev
, r10b
);
4572 int first_slot
= slot
;
4574 if (s
> (PAGE_SIZE
>> 9))
4578 int d
= r10b
->devs
[slot
].devnum
;
4579 struct md_rdev
*rdev
= conf
->mirrors
[d
].rdev
;
4582 test_bit(Faulty
, &rdev
->flags
) ||
4583 !test_bit(In_sync
, &rdev
->flags
))
4586 addr
= r10b
->devs
[slot
].addr
+ idx
* PAGE_SIZE
;
4587 success
= sync_page_io(rdev
,
4596 if (slot
>= conf
->copies
)
4598 if (slot
== first_slot
)
4602 /* couldn't read this block, must give up */
4603 set_bit(MD_RECOVERY_INTR
,
4613 static void end_reshape_write(struct bio
*bio
, int error
)
4615 int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
4616 struct r10bio
*r10_bio
= bio
->bi_private
;
4617 struct mddev
*mddev
= r10_bio
->mddev
;
4618 struct r10conf
*conf
= mddev
->private;
4622 struct md_rdev
*rdev
= NULL
;
4624 d
= find_bio_disk(conf
, r10_bio
, bio
, &slot
, &repl
);
4626 rdev
= conf
->mirrors
[d
].replacement
;
4629 rdev
= conf
->mirrors
[d
].rdev
;
4633 /* FIXME should record badblock */
4634 md_error(mddev
, rdev
);
4637 rdev_dec_pending(rdev
, mddev
);
4638 end_reshape_request(r10_bio
);
4641 static void end_reshape_request(struct r10bio
*r10_bio
)
4643 if (!atomic_dec_and_test(&r10_bio
->remaining
))
4645 md_done_sync(r10_bio
->mddev
, r10_bio
->sectors
, 1);
4646 bio_put(r10_bio
->master_bio
);
4650 static void raid10_finish_reshape(struct mddev
*mddev
)
4652 struct r10conf
*conf
= mddev
->private;
4654 if (test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
))
4657 if (mddev
->delta_disks
> 0) {
4658 sector_t size
= raid10_size(mddev
, 0, 0);
4659 md_set_array_sectors(mddev
, size
);
4660 if (mddev
->recovery_cp
> mddev
->resync_max_sectors
) {
4661 mddev
->recovery_cp
= mddev
->resync_max_sectors
;
4662 set_bit(MD_RECOVERY_NEEDED
, &mddev
->recovery
);
4664 mddev
->resync_max_sectors
= size
;
4665 set_capacity(mddev
->gendisk
, mddev
->array_sectors
);
4666 revalidate_disk(mddev
->gendisk
);
4669 for (d
= conf
->geo
.raid_disks
;
4670 d
< conf
->geo
.raid_disks
- mddev
->delta_disks
;
4672 struct md_rdev
*rdev
= conf
->mirrors
[d
].rdev
;
4674 clear_bit(In_sync
, &rdev
->flags
);
4675 rdev
= conf
->mirrors
[d
].replacement
;
4677 clear_bit(In_sync
, &rdev
->flags
);
4680 mddev
->layout
= mddev
->new_layout
;
4681 mddev
->chunk_sectors
= 1 << conf
->geo
.chunk_shift
;
4682 mddev
->reshape_position
= MaxSector
;
4683 mddev
->delta_disks
= 0;
4684 mddev
->reshape_backwards
= 0;
4687 static struct md_personality raid10_personality
=
4691 .owner
= THIS_MODULE
,
4692 .make_request
= make_request
,
4694 .free
= raid10_free
,
4696 .error_handler
= error
,
4697 .hot_add_disk
= raid10_add_disk
,
4698 .hot_remove_disk
= raid10_remove_disk
,
4699 .spare_active
= raid10_spare_active
,
4700 .sync_request
= sync_request
,
4701 .quiesce
= raid10_quiesce
,
4702 .size
= raid10_size
,
4703 .resize
= raid10_resize
,
4704 .takeover
= raid10_takeover
,
4705 .check_reshape
= raid10_check_reshape
,
4706 .start_reshape
= raid10_start_reshape
,
4707 .finish_reshape
= raid10_finish_reshape
,
4708 .congested
= raid10_congested
,
4709 .mergeable_bvec
= raid10_mergeable_bvec
,
4712 static int __init
raid_init(void)
4714 return register_md_personality(&raid10_personality
);
4717 static void raid_exit(void)
4719 unregister_md_personality(&raid10_personality
);
4722 module_init(raid_init
);
4723 module_exit(raid_exit
);
4724 MODULE_LICENSE("GPL");
4725 MODULE_DESCRIPTION("RAID10 (striped mirror) personality for MD");
4726 MODULE_ALIAS("md-personality-9"); /* RAID10 */
4727 MODULE_ALIAS("md-raid10");
4728 MODULE_ALIAS("md-level-10");
4730 module_param(max_queued_requests
, int, S_IRUGO
|S_IWUSR
);