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 )
42 * The data to be stored is divided into chunks using chunksize.
43 * Each device is divided into far_copies sections.
44 * In each section, chunks are laid out in a style similar to raid0, but
45 * near_copies copies of each chunk is stored (each on a different drive).
46 * The starting device for each section is offset near_copies from the starting
47 * device of the previous section.
48 * Thus they are (near_copies*far_copies) of each chunk, and each is on a different
50 * near_copies and far_copies must be at least one, and their product is at most
53 * If far_offset is true, then the far_copies are handled a bit differently.
54 * The copies are still in different stripes, but instead of be very far apart
55 * on disk, there are adjacent stripes.
59 * Number of guaranteed r10bios in case of extreme VM load:
61 #define NR_RAID10_BIOS 256
63 /* when we get a read error on a read-only array, we redirect to another
64 * device without failing the first device, or trying to over-write to
65 * correct the read error. To keep track of bad blocks on a per-bio
66 * level, we store IO_BLOCKED in the appropriate 'bios' pointer
68 #define IO_BLOCKED ((struct bio *)1)
69 /* When we successfully write to a known bad-block, we need to remove the
70 * bad-block marking which must be done from process context. So we record
71 * the success by setting devs[n].bio to IO_MADE_GOOD
73 #define IO_MADE_GOOD ((struct bio *)2)
75 #define BIO_SPECIAL(bio) ((unsigned long)bio <= 2)
77 /* When there are this many requests queued to be written by
78 * the raid10 thread, we become 'congested' to provide back-pressure
81 static int max_queued_requests
= 1024;
83 static void allow_barrier(struct r10conf
*conf
);
84 static void lower_barrier(struct r10conf
*conf
);
85 static int enough(struct r10conf
*conf
, int ignore
);
86 static sector_t
reshape_request(struct mddev
*mddev
, sector_t sector_nr
,
88 static void reshape_request_write(struct mddev
*mddev
, struct r10bio
*r10_bio
);
89 static void end_reshape_write(struct bio
*bio
, int error
);
90 static void end_reshape(struct r10conf
*conf
);
92 static void * r10bio_pool_alloc(gfp_t gfp_flags
, void *data
)
94 struct r10conf
*conf
= data
;
95 int size
= offsetof(struct r10bio
, devs
[conf
->copies
]);
97 /* allocate a r10bio with room for raid_disks entries in the
99 return kzalloc(size
, gfp_flags
);
102 static void r10bio_pool_free(void *r10_bio
, void *data
)
107 /* Maximum size of each resync request */
108 #define RESYNC_BLOCK_SIZE (64*1024)
109 #define RESYNC_PAGES ((RESYNC_BLOCK_SIZE + PAGE_SIZE-1) / PAGE_SIZE)
110 /* amount of memory to reserve for resync requests */
111 #define RESYNC_WINDOW (1024*1024)
112 /* maximum number of concurrent requests, memory permitting */
113 #define RESYNC_DEPTH (32*1024*1024/RESYNC_BLOCK_SIZE)
116 * When performing a resync, we need to read and compare, so
117 * we need as many pages are there are copies.
118 * When performing a recovery, we need 2 bios, one for read,
119 * one for write (we recover only one drive per r10buf)
122 static void * r10buf_pool_alloc(gfp_t gfp_flags
, void *data
)
124 struct r10conf
*conf
= data
;
126 struct r10bio
*r10_bio
;
131 r10_bio
= r10bio_pool_alloc(gfp_flags
, conf
);
135 if (test_bit(MD_RECOVERY_SYNC
, &conf
->mddev
->recovery
) ||
136 test_bit(MD_RECOVERY_RESHAPE
, &conf
->mddev
->recovery
))
137 nalloc
= conf
->copies
; /* resync */
139 nalloc
= 2; /* recovery */
144 for (j
= nalloc
; j
-- ; ) {
145 bio
= bio_kmalloc(gfp_flags
, RESYNC_PAGES
);
148 r10_bio
->devs
[j
].bio
= bio
;
149 if (!conf
->have_replacement
)
151 bio
= bio_kmalloc(gfp_flags
, RESYNC_PAGES
);
154 r10_bio
->devs
[j
].repl_bio
= bio
;
157 * Allocate RESYNC_PAGES data pages and attach them
160 for (j
= 0 ; j
< nalloc
; j
++) {
161 struct bio
*rbio
= r10_bio
->devs
[j
].repl_bio
;
162 bio
= r10_bio
->devs
[j
].bio
;
163 for (i
= 0; i
< RESYNC_PAGES
; i
++) {
164 if (j
> 0 && !test_bit(MD_RECOVERY_SYNC
,
165 &conf
->mddev
->recovery
)) {
166 /* we can share bv_page's during recovery
168 struct bio
*rbio
= r10_bio
->devs
[0].bio
;
169 page
= rbio
->bi_io_vec
[i
].bv_page
;
172 page
= alloc_page(gfp_flags
);
176 bio
->bi_io_vec
[i
].bv_page
= page
;
178 rbio
->bi_io_vec
[i
].bv_page
= page
;
186 safe_put_page(bio
->bi_io_vec
[i
-1].bv_page
);
188 for (i
= 0; i
< RESYNC_PAGES
; i
++)
189 safe_put_page(r10_bio
->devs
[j
].bio
->bi_io_vec
[i
].bv_page
);
192 for ( ; j
< nalloc
; j
++) {
193 if (r10_bio
->devs
[j
].bio
)
194 bio_put(r10_bio
->devs
[j
].bio
);
195 if (r10_bio
->devs
[j
].repl_bio
)
196 bio_put(r10_bio
->devs
[j
].repl_bio
);
198 r10bio_pool_free(r10_bio
, conf
);
202 static void r10buf_pool_free(void *__r10_bio
, void *data
)
205 struct r10conf
*conf
= data
;
206 struct r10bio
*r10bio
= __r10_bio
;
209 for (j
=0; j
< conf
->copies
; j
++) {
210 struct bio
*bio
= r10bio
->devs
[j
].bio
;
212 for (i
= 0; i
< RESYNC_PAGES
; i
++) {
213 safe_put_page(bio
->bi_io_vec
[i
].bv_page
);
214 bio
->bi_io_vec
[i
].bv_page
= NULL
;
218 bio
= r10bio
->devs
[j
].repl_bio
;
222 r10bio_pool_free(r10bio
, conf
);
225 static void put_all_bios(struct r10conf
*conf
, struct r10bio
*r10_bio
)
229 for (i
= 0; i
< conf
->copies
; i
++) {
230 struct bio
**bio
= & r10_bio
->devs
[i
].bio
;
231 if (!BIO_SPECIAL(*bio
))
234 bio
= &r10_bio
->devs
[i
].repl_bio
;
235 if (r10_bio
->read_slot
< 0 && !BIO_SPECIAL(*bio
))
241 static void free_r10bio(struct r10bio
*r10_bio
)
243 struct r10conf
*conf
= r10_bio
->mddev
->private;
245 put_all_bios(conf
, r10_bio
);
246 mempool_free(r10_bio
, conf
->r10bio_pool
);
249 static void put_buf(struct r10bio
*r10_bio
)
251 struct r10conf
*conf
= r10_bio
->mddev
->private;
253 mempool_free(r10_bio
, conf
->r10buf_pool
);
258 static void reschedule_retry(struct r10bio
*r10_bio
)
261 struct mddev
*mddev
= r10_bio
->mddev
;
262 struct r10conf
*conf
= mddev
->private;
264 spin_lock_irqsave(&conf
->device_lock
, flags
);
265 list_add(&r10_bio
->retry_list
, &conf
->retry_list
);
267 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
269 /* wake up frozen array... */
270 wake_up(&conf
->wait_barrier
);
272 md_wakeup_thread(mddev
->thread
);
276 * raid_end_bio_io() is called when we have finished servicing a mirrored
277 * operation and are ready to return a success/failure code to the buffer
280 static void raid_end_bio_io(struct r10bio
*r10_bio
)
282 struct bio
*bio
= r10_bio
->master_bio
;
284 struct r10conf
*conf
= r10_bio
->mddev
->private;
286 if (bio
->bi_phys_segments
) {
288 spin_lock_irqsave(&conf
->device_lock
, flags
);
289 bio
->bi_phys_segments
--;
290 done
= (bio
->bi_phys_segments
== 0);
291 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
294 if (!test_bit(R10BIO_Uptodate
, &r10_bio
->state
))
295 clear_bit(BIO_UPTODATE
, &bio
->bi_flags
);
299 * Wake up any possible resync thread that waits for the device
304 free_r10bio(r10_bio
);
308 * Update disk head position estimator based on IRQ completion info.
310 static inline void update_head_pos(int slot
, struct r10bio
*r10_bio
)
312 struct r10conf
*conf
= r10_bio
->mddev
->private;
314 conf
->mirrors
[r10_bio
->devs
[slot
].devnum
].head_position
=
315 r10_bio
->devs
[slot
].addr
+ (r10_bio
->sectors
);
319 * Find the disk number which triggered given bio
321 static int find_bio_disk(struct r10conf
*conf
, struct r10bio
*r10_bio
,
322 struct bio
*bio
, int *slotp
, int *replp
)
327 for (slot
= 0; slot
< conf
->copies
; slot
++) {
328 if (r10_bio
->devs
[slot
].bio
== bio
)
330 if (r10_bio
->devs
[slot
].repl_bio
== bio
) {
336 BUG_ON(slot
== conf
->copies
);
337 update_head_pos(slot
, r10_bio
);
343 return r10_bio
->devs
[slot
].devnum
;
346 static void raid10_end_read_request(struct bio
*bio
, int error
)
348 int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
349 struct r10bio
*r10_bio
= bio
->bi_private
;
351 struct md_rdev
*rdev
;
352 struct r10conf
*conf
= r10_bio
->mddev
->private;
355 slot
= r10_bio
->read_slot
;
356 dev
= r10_bio
->devs
[slot
].devnum
;
357 rdev
= r10_bio
->devs
[slot
].rdev
;
359 * this branch is our 'one mirror IO has finished' event handler:
361 update_head_pos(slot
, r10_bio
);
365 * Set R10BIO_Uptodate in our master bio, so that
366 * we will return a good error code to the higher
367 * levels even if IO on some other mirrored buffer fails.
369 * The 'master' represents the composite IO operation to
370 * user-side. So if something waits for IO, then it will
371 * wait for the 'master' bio.
373 set_bit(R10BIO_Uptodate
, &r10_bio
->state
);
375 /* If all other devices that store this block have
376 * failed, we want to return the error upwards rather
377 * than fail the last device. Here we redefine
378 * "uptodate" to mean "Don't want to retry"
381 spin_lock_irqsave(&conf
->device_lock
, flags
);
382 if (!enough(conf
, rdev
->raid_disk
))
384 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
387 raid_end_bio_io(r10_bio
);
388 rdev_dec_pending(rdev
, conf
->mddev
);
391 * oops, read error - keep the refcount on the rdev
393 char b
[BDEVNAME_SIZE
];
394 printk_ratelimited(KERN_ERR
395 "md/raid10:%s: %s: rescheduling sector %llu\n",
397 bdevname(rdev
->bdev
, b
),
398 (unsigned long long)r10_bio
->sector
);
399 set_bit(R10BIO_ReadError
, &r10_bio
->state
);
400 reschedule_retry(r10_bio
);
404 static void close_write(struct r10bio
*r10_bio
)
406 /* clear the bitmap if all writes complete successfully */
407 bitmap_endwrite(r10_bio
->mddev
->bitmap
, r10_bio
->sector
,
409 !test_bit(R10BIO_Degraded
, &r10_bio
->state
),
411 md_write_end(r10_bio
->mddev
);
414 static void one_write_done(struct r10bio
*r10_bio
)
416 if (atomic_dec_and_test(&r10_bio
->remaining
)) {
417 if (test_bit(R10BIO_WriteError
, &r10_bio
->state
))
418 reschedule_retry(r10_bio
);
420 close_write(r10_bio
);
421 if (test_bit(R10BIO_MadeGood
, &r10_bio
->state
))
422 reschedule_retry(r10_bio
);
424 raid_end_bio_io(r10_bio
);
429 static void raid10_end_write_request(struct bio
*bio
, int error
)
431 int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
432 struct r10bio
*r10_bio
= bio
->bi_private
;
435 struct r10conf
*conf
= r10_bio
->mddev
->private;
437 struct md_rdev
*rdev
= NULL
;
439 dev
= find_bio_disk(conf
, r10_bio
, bio
, &slot
, &repl
);
442 rdev
= conf
->mirrors
[dev
].replacement
;
446 rdev
= conf
->mirrors
[dev
].rdev
;
449 * this branch is our 'one mirror IO has finished' event handler:
453 /* Never record new bad blocks to replacement,
456 md_error(rdev
->mddev
, rdev
);
458 set_bit(WriteErrorSeen
, &rdev
->flags
);
459 if (!test_and_set_bit(WantReplacement
, &rdev
->flags
))
460 set_bit(MD_RECOVERY_NEEDED
,
461 &rdev
->mddev
->recovery
);
462 set_bit(R10BIO_WriteError
, &r10_bio
->state
);
467 * Set R10BIO_Uptodate in our master bio, so that
468 * we will return a good error code for to the higher
469 * levels even if IO on some other mirrored buffer fails.
471 * The 'master' represents the composite IO operation to
472 * user-side. So if something waits for IO, then it will
473 * wait for the 'master' bio.
478 set_bit(R10BIO_Uptodate
, &r10_bio
->state
);
480 /* Maybe we can clear some bad blocks. */
481 if (is_badblock(rdev
,
482 r10_bio
->devs
[slot
].addr
,
484 &first_bad
, &bad_sectors
)) {
487 r10_bio
->devs
[slot
].repl_bio
= IO_MADE_GOOD
;
489 r10_bio
->devs
[slot
].bio
= IO_MADE_GOOD
;
491 set_bit(R10BIO_MadeGood
, &r10_bio
->state
);
497 * Let's see if all mirrored write operations have finished
500 one_write_done(r10_bio
);
502 rdev_dec_pending(rdev
, conf
->mddev
);
506 * RAID10 layout manager
507 * As well as the chunksize and raid_disks count, there are two
508 * parameters: near_copies and far_copies.
509 * near_copies * far_copies must be <= raid_disks.
510 * Normally one of these will be 1.
511 * If both are 1, we get raid0.
512 * If near_copies == raid_disks, we get raid1.
514 * Chunks are laid out in raid0 style with near_copies copies of the
515 * first chunk, followed by near_copies copies of the next chunk and
517 * If far_copies > 1, then after 1/far_copies of the array has been assigned
518 * as described above, we start again with a device offset of near_copies.
519 * So we effectively have another copy of the whole array further down all
520 * the drives, but with blocks on different drives.
521 * With this layout, and block is never stored twice on the one device.
523 * raid10_find_phys finds the sector offset of a given virtual sector
524 * on each device that it is on.
526 * raid10_find_virt does the reverse mapping, from a device and a
527 * sector offset to a virtual address
530 static void __raid10_find_phys(struct geom
*geo
, struct r10bio
*r10bio
)
539 /* now calculate first sector/dev */
540 chunk
= r10bio
->sector
>> geo
->chunk_shift
;
541 sector
= r10bio
->sector
& geo
->chunk_mask
;
543 chunk
*= geo
->near_copies
;
545 dev
= sector_div(stripe
, geo
->raid_disks
);
547 stripe
*= geo
->far_copies
;
549 sector
+= stripe
<< geo
->chunk_shift
;
551 /* and calculate all the others */
552 for (n
= 0; n
< geo
->near_copies
; n
++) {
555 r10bio
->devs
[slot
].addr
= sector
;
556 r10bio
->devs
[slot
].devnum
= d
;
559 for (f
= 1; f
< geo
->far_copies
; f
++) {
560 d
+= geo
->near_copies
;
561 if (d
>= geo
->raid_disks
)
562 d
-= geo
->raid_disks
;
564 r10bio
->devs
[slot
].devnum
= d
;
565 r10bio
->devs
[slot
].addr
= s
;
569 if (dev
>= geo
->raid_disks
) {
571 sector
+= (geo
->chunk_mask
+ 1);
576 static void raid10_find_phys(struct r10conf
*conf
, struct r10bio
*r10bio
)
578 struct geom
*geo
= &conf
->geo
;
580 if (conf
->reshape_progress
!= MaxSector
&&
581 ((r10bio
->sector
>= conf
->reshape_progress
) !=
582 conf
->mddev
->reshape_backwards
)) {
583 set_bit(R10BIO_Previous
, &r10bio
->state
);
586 clear_bit(R10BIO_Previous
, &r10bio
->state
);
588 __raid10_find_phys(geo
, r10bio
);
591 static sector_t
raid10_find_virt(struct r10conf
*conf
, sector_t sector
, int dev
)
593 sector_t offset
, chunk
, vchunk
;
594 /* Never use conf->prev as this is only called during resync
595 * or recovery, so reshape isn't happening
597 struct geom
*geo
= &conf
->geo
;
599 offset
= sector
& geo
->chunk_mask
;
600 if (geo
->far_offset
) {
602 chunk
= sector
>> geo
->chunk_shift
;
603 fc
= sector_div(chunk
, geo
->far_copies
);
604 dev
-= fc
* geo
->near_copies
;
606 dev
+= geo
->raid_disks
;
608 while (sector
>= geo
->stride
) {
609 sector
-= geo
->stride
;
610 if (dev
< geo
->near_copies
)
611 dev
+= geo
->raid_disks
- geo
->near_copies
;
613 dev
-= geo
->near_copies
;
615 chunk
= sector
>> geo
->chunk_shift
;
617 vchunk
= chunk
* geo
->raid_disks
+ dev
;
618 sector_div(vchunk
, geo
->near_copies
);
619 return (vchunk
<< geo
->chunk_shift
) + offset
;
623 * raid10_mergeable_bvec -- tell bio layer if a two requests can be merged
625 * @bvm: properties of new bio
626 * @biovec: the request that could be merged to it.
628 * Return amount of bytes we can accept at this offset
629 * This requires checking for end-of-chunk if near_copies != raid_disks,
630 * and for subordinate merge_bvec_fns if merge_check_needed.
632 static int raid10_mergeable_bvec(struct request_queue
*q
,
633 struct bvec_merge_data
*bvm
,
634 struct bio_vec
*biovec
)
636 struct mddev
*mddev
= q
->queuedata
;
637 struct r10conf
*conf
= mddev
->private;
638 sector_t sector
= bvm
->bi_sector
+ get_start_sect(bvm
->bi_bdev
);
640 unsigned int chunk_sectors
;
641 unsigned int bio_sectors
= bvm
->bi_size
>> 9;
642 struct geom
*geo
= &conf
->geo
;
644 chunk_sectors
= (conf
->geo
.chunk_mask
& conf
->prev
.chunk_mask
) + 1;
645 if (conf
->reshape_progress
!= MaxSector
&&
646 ((sector
>= conf
->reshape_progress
) !=
647 conf
->mddev
->reshape_backwards
))
650 if (geo
->near_copies
< geo
->raid_disks
) {
651 max
= (chunk_sectors
- ((sector
& (chunk_sectors
- 1))
652 + bio_sectors
)) << 9;
654 /* bio_add cannot handle a negative return */
656 if (max
<= biovec
->bv_len
&& bio_sectors
== 0)
657 return biovec
->bv_len
;
659 max
= biovec
->bv_len
;
661 if (mddev
->merge_check_needed
) {
663 struct r10bio r10_bio
;
664 struct r10dev devs
[conf
->copies
];
666 struct r10bio
*r10_bio
= &on_stack
.r10_bio
;
668 if (conf
->reshape_progress
!= MaxSector
) {
669 /* Cannot give any guidance during reshape */
670 if (max
<= biovec
->bv_len
&& bio_sectors
== 0)
671 return biovec
->bv_len
;
674 r10_bio
->sector
= sector
;
675 raid10_find_phys(conf
, r10_bio
);
677 for (s
= 0; s
< conf
->copies
; s
++) {
678 int disk
= r10_bio
->devs
[s
].devnum
;
679 struct md_rdev
*rdev
= rcu_dereference(
680 conf
->mirrors
[disk
].rdev
);
681 if (rdev
&& !test_bit(Faulty
, &rdev
->flags
)) {
682 struct request_queue
*q
=
683 bdev_get_queue(rdev
->bdev
);
684 if (q
->merge_bvec_fn
) {
685 bvm
->bi_sector
= r10_bio
->devs
[s
].addr
687 bvm
->bi_bdev
= rdev
->bdev
;
688 max
= min(max
, q
->merge_bvec_fn(
692 rdev
= rcu_dereference(conf
->mirrors
[disk
].replacement
);
693 if (rdev
&& !test_bit(Faulty
, &rdev
->flags
)) {
694 struct request_queue
*q
=
695 bdev_get_queue(rdev
->bdev
);
696 if (q
->merge_bvec_fn
) {
697 bvm
->bi_sector
= r10_bio
->devs
[s
].addr
699 bvm
->bi_bdev
= rdev
->bdev
;
700 max
= min(max
, q
->merge_bvec_fn(
711 * This routine returns the disk from which the requested read should
712 * be done. There is a per-array 'next expected sequential IO' sector
713 * number - if this matches on the next IO then we use the last disk.
714 * There is also a per-disk 'last know head position' sector that is
715 * maintained from IRQ contexts, both the normal and the resync IO
716 * completion handlers update this position correctly. If there is no
717 * perfect sequential match then we pick the disk whose head is closest.
719 * If there are 2 mirrors in the same 2 devices, performance degrades
720 * because position is mirror, not device based.
722 * The rdev for the device selected will have nr_pending incremented.
726 * FIXME: possibly should rethink readbalancing and do it differently
727 * depending on near_copies / far_copies geometry.
729 static struct md_rdev
*read_balance(struct r10conf
*conf
,
730 struct r10bio
*r10_bio
,
733 const sector_t this_sector
= r10_bio
->sector
;
735 int sectors
= r10_bio
->sectors
;
736 int best_good_sectors
;
737 sector_t new_distance
, best_dist
;
738 struct md_rdev
*best_rdev
, *rdev
= NULL
;
741 struct geom
*geo
= &conf
->geo
;
743 raid10_find_phys(conf
, r10_bio
);
746 sectors
= r10_bio
->sectors
;
749 best_dist
= MaxSector
;
750 best_good_sectors
= 0;
753 * Check if we can balance. We can balance on the whole
754 * device if no resync is going on (recovery is ok), or below
755 * the resync window. We take the first readable disk when
756 * above the resync window.
758 if (conf
->mddev
->recovery_cp
< MaxSector
759 && (this_sector
+ sectors
>= conf
->next_resync
))
762 for (slot
= 0; slot
< conf
->copies
; slot
++) {
767 if (r10_bio
->devs
[slot
].bio
== IO_BLOCKED
)
769 disk
= r10_bio
->devs
[slot
].devnum
;
770 rdev
= rcu_dereference(conf
->mirrors
[disk
].replacement
);
771 if (rdev
== NULL
|| test_bit(Faulty
, &rdev
->flags
) ||
772 test_bit(Unmerged
, &rdev
->flags
) ||
773 r10_bio
->devs
[slot
].addr
+ sectors
> rdev
->recovery_offset
)
774 rdev
= rcu_dereference(conf
->mirrors
[disk
].rdev
);
776 test_bit(Faulty
, &rdev
->flags
) ||
777 test_bit(Unmerged
, &rdev
->flags
))
779 if (!test_bit(In_sync
, &rdev
->flags
) &&
780 r10_bio
->devs
[slot
].addr
+ sectors
> rdev
->recovery_offset
)
783 dev_sector
= r10_bio
->devs
[slot
].addr
;
784 if (is_badblock(rdev
, dev_sector
, sectors
,
785 &first_bad
, &bad_sectors
)) {
786 if (best_dist
< MaxSector
)
787 /* Already have a better slot */
789 if (first_bad
<= dev_sector
) {
790 /* Cannot read here. If this is the
791 * 'primary' device, then we must not read
792 * beyond 'bad_sectors' from another device.
794 bad_sectors
-= (dev_sector
- first_bad
);
795 if (!do_balance
&& sectors
> bad_sectors
)
796 sectors
= bad_sectors
;
797 if (best_good_sectors
> sectors
)
798 best_good_sectors
= sectors
;
800 sector_t good_sectors
=
801 first_bad
- dev_sector
;
802 if (good_sectors
> best_good_sectors
) {
803 best_good_sectors
= good_sectors
;
808 /* Must read from here */
813 best_good_sectors
= sectors
;
818 /* This optimisation is debatable, and completely destroys
819 * sequential read speed for 'far copies' arrays. So only
820 * keep it for 'near' arrays, and review those later.
822 if (geo
->near_copies
> 1 && !atomic_read(&rdev
->nr_pending
))
825 /* for far > 1 always use the lowest address */
826 if (geo
->far_copies
> 1)
827 new_distance
= r10_bio
->devs
[slot
].addr
;
829 new_distance
= abs(r10_bio
->devs
[slot
].addr
-
830 conf
->mirrors
[disk
].head_position
);
831 if (new_distance
< best_dist
) {
832 best_dist
= new_distance
;
837 if (slot
>= conf
->copies
) {
843 atomic_inc(&rdev
->nr_pending
);
844 if (test_bit(Faulty
, &rdev
->flags
)) {
845 /* Cannot risk returning a device that failed
846 * before we inc'ed nr_pending
848 rdev_dec_pending(rdev
, conf
->mddev
);
851 r10_bio
->read_slot
= slot
;
855 *max_sectors
= best_good_sectors
;
860 int md_raid10_congested(struct mddev
*mddev
, int bits
)
862 struct r10conf
*conf
= mddev
->private;
865 if ((bits
& (1 << BDI_async_congested
)) &&
866 conf
->pending_count
>= max_queued_requests
)
871 (i
< conf
->geo
.raid_disks
|| i
< conf
->prev
.raid_disks
)
874 struct md_rdev
*rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
875 if (rdev
&& !test_bit(Faulty
, &rdev
->flags
)) {
876 struct request_queue
*q
= bdev_get_queue(rdev
->bdev
);
878 ret
|= bdi_congested(&q
->backing_dev_info
, bits
);
884 EXPORT_SYMBOL_GPL(md_raid10_congested
);
886 static int raid10_congested(void *data
, int bits
)
888 struct mddev
*mddev
= data
;
890 return mddev_congested(mddev
, bits
) ||
891 md_raid10_congested(mddev
, bits
);
894 static void flush_pending_writes(struct r10conf
*conf
)
896 /* Any writes that have been queued but are awaiting
897 * bitmap updates get flushed here.
899 spin_lock_irq(&conf
->device_lock
);
901 if (conf
->pending_bio_list
.head
) {
903 bio
= bio_list_get(&conf
->pending_bio_list
);
904 conf
->pending_count
= 0;
905 spin_unlock_irq(&conf
->device_lock
);
906 /* flush any pending bitmap writes to disk
907 * before proceeding w/ I/O */
908 bitmap_unplug(conf
->mddev
->bitmap
);
909 wake_up(&conf
->wait_barrier
);
911 while (bio
) { /* submit pending writes */
912 struct bio
*next
= bio
->bi_next
;
914 if (unlikely((bio
->bi_rw
& REQ_DISCARD
) &&
915 !blk_queue_discard(bdev_get_queue(bio
->bi_bdev
))))
919 generic_make_request(bio
);
923 spin_unlock_irq(&conf
->device_lock
);
927 * Sometimes we need to suspend IO while we do something else,
928 * either some resync/recovery, or reconfigure the array.
929 * To do this we raise a 'barrier'.
930 * The 'barrier' is a counter that can be raised multiple times
931 * to count how many activities are happening which preclude
933 * We can only raise the barrier if there is no pending IO.
934 * i.e. if nr_pending == 0.
935 * We choose only to raise the barrier if no-one is waiting for the
936 * barrier to go down. This means that as soon as an IO request
937 * is ready, no other operations which require a barrier will start
938 * until the IO request has had a chance.
940 * So: regular IO calls 'wait_barrier'. When that returns there
941 * is no backgroup IO happening, It must arrange to call
942 * allow_barrier when it has finished its IO.
943 * backgroup IO calls must call raise_barrier. Once that returns
944 * there is no normal IO happeing. It must arrange to call
945 * lower_barrier when the particular background IO completes.
948 static void raise_barrier(struct r10conf
*conf
, int force
)
950 BUG_ON(force
&& !conf
->barrier
);
951 spin_lock_irq(&conf
->resync_lock
);
953 /* Wait until no block IO is waiting (unless 'force') */
954 wait_event_lock_irq(conf
->wait_barrier
, force
|| !conf
->nr_waiting
,
957 /* block any new IO from starting */
960 /* Now wait for all pending IO to complete */
961 wait_event_lock_irq(conf
->wait_barrier
,
962 !conf
->nr_pending
&& conf
->barrier
< RESYNC_DEPTH
,
965 spin_unlock_irq(&conf
->resync_lock
);
968 static void lower_barrier(struct r10conf
*conf
)
971 spin_lock_irqsave(&conf
->resync_lock
, flags
);
973 spin_unlock_irqrestore(&conf
->resync_lock
, flags
);
974 wake_up(&conf
->wait_barrier
);
977 static void wait_barrier(struct r10conf
*conf
)
979 spin_lock_irq(&conf
->resync_lock
);
982 /* Wait for the barrier to drop.
983 * However if there are already pending
984 * requests (preventing the barrier from
985 * rising completely), and the
986 * pre-process bio queue isn't empty,
987 * then don't wait, as we need to empty
988 * that queue to get the nr_pending
991 wait_event_lock_irq(conf
->wait_barrier
,
995 !bio_list_empty(current
->bio_list
)),
1000 spin_unlock_irq(&conf
->resync_lock
);
1003 static void allow_barrier(struct r10conf
*conf
)
1005 unsigned long flags
;
1006 spin_lock_irqsave(&conf
->resync_lock
, flags
);
1008 spin_unlock_irqrestore(&conf
->resync_lock
, flags
);
1009 wake_up(&conf
->wait_barrier
);
1012 static void freeze_array(struct r10conf
*conf
)
1014 /* stop syncio and normal IO and wait for everything to
1016 * We increment barrier and nr_waiting, and then
1017 * wait until nr_pending match nr_queued+1
1018 * This is called in the context of one normal IO request
1019 * that has failed. Thus any sync request that might be pending
1020 * will be blocked by nr_pending, and we need to wait for
1021 * pending IO requests to complete or be queued for re-try.
1022 * Thus the number queued (nr_queued) plus this request (1)
1023 * must match the number of pending IOs (nr_pending) before
1026 spin_lock_irq(&conf
->resync_lock
);
1029 wait_event_lock_irq_cmd(conf
->wait_barrier
,
1030 conf
->nr_pending
== conf
->nr_queued
+1,
1032 flush_pending_writes(conf
));
1034 spin_unlock_irq(&conf
->resync_lock
);
1037 static void unfreeze_array(struct r10conf
*conf
)
1039 /* reverse the effect of the freeze */
1040 spin_lock_irq(&conf
->resync_lock
);
1043 wake_up(&conf
->wait_barrier
);
1044 spin_unlock_irq(&conf
->resync_lock
);
1047 static sector_t
choose_data_offset(struct r10bio
*r10_bio
,
1048 struct md_rdev
*rdev
)
1050 if (!test_bit(MD_RECOVERY_RESHAPE
, &rdev
->mddev
->recovery
) ||
1051 test_bit(R10BIO_Previous
, &r10_bio
->state
))
1052 return rdev
->data_offset
;
1054 return rdev
->new_data_offset
;
1057 struct raid10_plug_cb
{
1058 struct blk_plug_cb cb
;
1059 struct bio_list pending
;
1063 static void raid10_unplug(struct blk_plug_cb
*cb
, bool from_schedule
)
1065 struct raid10_plug_cb
*plug
= container_of(cb
, struct raid10_plug_cb
,
1067 struct mddev
*mddev
= plug
->cb
.data
;
1068 struct r10conf
*conf
= mddev
->private;
1071 if (from_schedule
|| current
->bio_list
) {
1072 spin_lock_irq(&conf
->device_lock
);
1073 bio_list_merge(&conf
->pending_bio_list
, &plug
->pending
);
1074 conf
->pending_count
+= plug
->pending_cnt
;
1075 spin_unlock_irq(&conf
->device_lock
);
1076 md_wakeup_thread(mddev
->thread
);
1081 /* we aren't scheduling, so we can do the write-out directly. */
1082 bio
= bio_list_get(&plug
->pending
);
1083 bitmap_unplug(mddev
->bitmap
);
1084 wake_up(&conf
->wait_barrier
);
1086 while (bio
) { /* submit pending writes */
1087 struct bio
*next
= bio
->bi_next
;
1088 bio
->bi_next
= NULL
;
1089 generic_make_request(bio
);
1095 static void make_request(struct mddev
*mddev
, struct bio
* bio
)
1097 struct r10conf
*conf
= mddev
->private;
1098 struct r10bio
*r10_bio
;
1099 struct bio
*read_bio
;
1101 sector_t chunk_mask
= (conf
->geo
.chunk_mask
& conf
->prev
.chunk_mask
);
1102 int chunk_sects
= chunk_mask
+ 1;
1103 const int rw
= bio_data_dir(bio
);
1104 const unsigned long do_sync
= (bio
->bi_rw
& REQ_SYNC
);
1105 const unsigned long do_fua
= (bio
->bi_rw
& REQ_FUA
);
1106 const unsigned long do_discard
= (bio
->bi_rw
1107 & (REQ_DISCARD
| REQ_SECURE
));
1108 unsigned long flags
;
1109 struct md_rdev
*blocked_rdev
;
1110 struct blk_plug_cb
*cb
;
1111 struct raid10_plug_cb
*plug
= NULL
;
1112 int sectors_handled
;
1116 if (unlikely(bio
->bi_rw
& REQ_FLUSH
)) {
1117 md_flush_request(mddev
, bio
);
1121 /* If this request crosses a chunk boundary, we need to
1122 * split it. This will only happen for 1 PAGE (or less) requests.
1124 if (unlikely((bio
->bi_sector
& chunk_mask
) + (bio
->bi_size
>> 9)
1126 && (conf
->geo
.near_copies
< conf
->geo
.raid_disks
1127 || conf
->prev
.near_copies
< conf
->prev
.raid_disks
))) {
1128 struct bio_pair
*bp
;
1129 /* Sanity check -- queue functions should prevent this happening */
1130 if ((bio
->bi_vcnt
!= 1 && bio
->bi_vcnt
!= 0) ||
1133 /* This is a one page bio that upper layers
1134 * refuse to split for us, so we need to split it.
1137 chunk_sects
- (bio
->bi_sector
& (chunk_sects
- 1)) );
1139 /* Each of these 'make_request' calls will call 'wait_barrier'.
1140 * If the first succeeds but the second blocks due to the resync
1141 * thread raising the barrier, we will deadlock because the
1142 * IO to the underlying device will be queued in generic_make_request
1143 * and will never complete, so will never reduce nr_pending.
1144 * So increment nr_waiting here so no new raise_barriers will
1145 * succeed, and so the second wait_barrier cannot block.
1147 spin_lock_irq(&conf
->resync_lock
);
1149 spin_unlock_irq(&conf
->resync_lock
);
1151 make_request(mddev
, &bp
->bio1
);
1152 make_request(mddev
, &bp
->bio2
);
1154 spin_lock_irq(&conf
->resync_lock
);
1156 wake_up(&conf
->wait_barrier
);
1157 spin_unlock_irq(&conf
->resync_lock
);
1159 bio_pair_release(bp
);
1162 printk("md/raid10:%s: make_request bug: can't convert block across chunks"
1163 " or bigger than %dk %llu %d\n", mdname(mddev
), chunk_sects
/2,
1164 (unsigned long long)bio
->bi_sector
, bio
->bi_size
>> 10);
1170 md_write_start(mddev
, bio
);
1173 * Register the new request and wait if the reconstruction
1174 * thread has put up a bar for new requests.
1175 * Continue immediately if no resync is active currently.
1179 sectors
= bio
->bi_size
>> 9;
1180 while (test_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
) &&
1181 bio
->bi_sector
< conf
->reshape_progress
&&
1182 bio
->bi_sector
+ sectors
> conf
->reshape_progress
) {
1183 /* IO spans the reshape position. Need to wait for
1186 allow_barrier(conf
);
1187 wait_event(conf
->wait_barrier
,
1188 conf
->reshape_progress
<= bio
->bi_sector
||
1189 conf
->reshape_progress
>= bio
->bi_sector
+ sectors
);
1192 if (test_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
) &&
1193 bio_data_dir(bio
) == WRITE
&&
1194 (mddev
->reshape_backwards
1195 ? (bio
->bi_sector
< conf
->reshape_safe
&&
1196 bio
->bi_sector
+ sectors
> conf
->reshape_progress
)
1197 : (bio
->bi_sector
+ sectors
> conf
->reshape_safe
&&
1198 bio
->bi_sector
< conf
->reshape_progress
))) {
1199 /* Need to update reshape_position in metadata */
1200 mddev
->reshape_position
= conf
->reshape_progress
;
1201 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
1202 set_bit(MD_CHANGE_PENDING
, &mddev
->flags
);
1203 md_wakeup_thread(mddev
->thread
);
1204 wait_event(mddev
->sb_wait
,
1205 !test_bit(MD_CHANGE_PENDING
, &mddev
->flags
));
1207 conf
->reshape_safe
= mddev
->reshape_position
;
1210 r10_bio
= mempool_alloc(conf
->r10bio_pool
, GFP_NOIO
);
1212 r10_bio
->master_bio
= bio
;
1213 r10_bio
->sectors
= sectors
;
1215 r10_bio
->mddev
= mddev
;
1216 r10_bio
->sector
= bio
->bi_sector
;
1219 /* We might need to issue multiple reads to different
1220 * devices if there are bad blocks around, so we keep
1221 * track of the number of reads in bio->bi_phys_segments.
1222 * If this is 0, there is only one r10_bio and no locking
1223 * will be needed when the request completes. If it is
1224 * non-zero, then it is the number of not-completed requests.
1226 bio
->bi_phys_segments
= 0;
1227 clear_bit(BIO_SEG_VALID
, &bio
->bi_flags
);
1231 * read balancing logic:
1233 struct md_rdev
*rdev
;
1237 rdev
= read_balance(conf
, r10_bio
, &max_sectors
);
1239 raid_end_bio_io(r10_bio
);
1242 slot
= r10_bio
->read_slot
;
1244 read_bio
= bio_clone_mddev(bio
, GFP_NOIO
, mddev
);
1245 md_trim_bio(read_bio
, r10_bio
->sector
- bio
->bi_sector
,
1248 r10_bio
->devs
[slot
].bio
= read_bio
;
1249 r10_bio
->devs
[slot
].rdev
= rdev
;
1251 read_bio
->bi_sector
= r10_bio
->devs
[slot
].addr
+
1252 choose_data_offset(r10_bio
, rdev
);
1253 read_bio
->bi_bdev
= rdev
->bdev
;
1254 read_bio
->bi_end_io
= raid10_end_read_request
;
1255 read_bio
->bi_rw
= READ
| do_sync
;
1256 read_bio
->bi_private
= r10_bio
;
1258 if (max_sectors
< r10_bio
->sectors
) {
1259 /* Could not read all from this device, so we will
1260 * need another r10_bio.
1262 sectors_handled
= (r10_bio
->sectors
+ max_sectors
1264 r10_bio
->sectors
= max_sectors
;
1265 spin_lock_irq(&conf
->device_lock
);
1266 if (bio
->bi_phys_segments
== 0)
1267 bio
->bi_phys_segments
= 2;
1269 bio
->bi_phys_segments
++;
1270 spin_unlock(&conf
->device_lock
);
1271 /* Cannot call generic_make_request directly
1272 * as that will be queued in __generic_make_request
1273 * and subsequent mempool_alloc might block
1274 * waiting for it. so hand bio over to raid10d.
1276 reschedule_retry(r10_bio
);
1278 r10_bio
= mempool_alloc(conf
->r10bio_pool
, GFP_NOIO
);
1280 r10_bio
->master_bio
= bio
;
1281 r10_bio
->sectors
= ((bio
->bi_size
>> 9)
1284 r10_bio
->mddev
= mddev
;
1285 r10_bio
->sector
= bio
->bi_sector
+ sectors_handled
;
1288 generic_make_request(read_bio
);
1295 if (conf
->pending_count
>= max_queued_requests
) {
1296 md_wakeup_thread(mddev
->thread
);
1297 wait_event(conf
->wait_barrier
,
1298 conf
->pending_count
< max_queued_requests
);
1300 /* first select target devices under rcu_lock and
1301 * inc refcount on their rdev. Record them by setting
1303 * If there are known/acknowledged bad blocks on any device
1304 * on which we have seen a write error, we want to avoid
1305 * writing to those blocks. This potentially requires several
1306 * writes to write around the bad blocks. Each set of writes
1307 * gets its own r10_bio with a set of bios attached. The number
1308 * of r10_bios is recored in bio->bi_phys_segments just as with
1312 r10_bio
->read_slot
= -1; /* make sure repl_bio gets freed */
1313 raid10_find_phys(conf
, r10_bio
);
1315 blocked_rdev
= NULL
;
1317 max_sectors
= r10_bio
->sectors
;
1319 for (i
= 0; i
< conf
->copies
; i
++) {
1320 int d
= r10_bio
->devs
[i
].devnum
;
1321 struct md_rdev
*rdev
= rcu_dereference(conf
->mirrors
[d
].rdev
);
1322 struct md_rdev
*rrdev
= rcu_dereference(
1323 conf
->mirrors
[d
].replacement
);
1326 if (rdev
&& unlikely(test_bit(Blocked
, &rdev
->flags
))) {
1327 atomic_inc(&rdev
->nr_pending
);
1328 blocked_rdev
= rdev
;
1331 if (rrdev
&& unlikely(test_bit(Blocked
, &rrdev
->flags
))) {
1332 atomic_inc(&rrdev
->nr_pending
);
1333 blocked_rdev
= rrdev
;
1336 if (rdev
&& (test_bit(Faulty
, &rdev
->flags
)
1337 || test_bit(Unmerged
, &rdev
->flags
)))
1339 if (rrdev
&& (test_bit(Faulty
, &rrdev
->flags
)
1340 || test_bit(Unmerged
, &rrdev
->flags
)))
1343 r10_bio
->devs
[i
].bio
= NULL
;
1344 r10_bio
->devs
[i
].repl_bio
= NULL
;
1346 if (!rdev
&& !rrdev
) {
1347 set_bit(R10BIO_Degraded
, &r10_bio
->state
);
1350 if (rdev
&& test_bit(WriteErrorSeen
, &rdev
->flags
)) {
1352 sector_t dev_sector
= r10_bio
->devs
[i
].addr
;
1356 is_bad
= is_badblock(rdev
, dev_sector
,
1358 &first_bad
, &bad_sectors
);
1360 /* Mustn't write here until the bad block
1363 atomic_inc(&rdev
->nr_pending
);
1364 set_bit(BlockedBadBlocks
, &rdev
->flags
);
1365 blocked_rdev
= rdev
;
1368 if (is_bad
&& first_bad
<= dev_sector
) {
1369 /* Cannot write here at all */
1370 bad_sectors
-= (dev_sector
- first_bad
);
1371 if (bad_sectors
< max_sectors
)
1372 /* Mustn't write more than bad_sectors
1373 * to other devices yet
1375 max_sectors
= bad_sectors
;
1376 /* We don't set R10BIO_Degraded as that
1377 * only applies if the disk is missing,
1378 * so it might be re-added, and we want to
1379 * know to recover this chunk.
1380 * In this case the device is here, and the
1381 * fact that this chunk is not in-sync is
1382 * recorded in the bad block log.
1387 int good_sectors
= first_bad
- dev_sector
;
1388 if (good_sectors
< max_sectors
)
1389 max_sectors
= good_sectors
;
1393 r10_bio
->devs
[i
].bio
= bio
;
1394 atomic_inc(&rdev
->nr_pending
);
1397 r10_bio
->devs
[i
].repl_bio
= bio
;
1398 atomic_inc(&rrdev
->nr_pending
);
1403 if (unlikely(blocked_rdev
)) {
1404 /* Have to wait for this device to get unblocked, then retry */
1408 for (j
= 0; j
< i
; j
++) {
1409 if (r10_bio
->devs
[j
].bio
) {
1410 d
= r10_bio
->devs
[j
].devnum
;
1411 rdev_dec_pending(conf
->mirrors
[d
].rdev
, mddev
);
1413 if (r10_bio
->devs
[j
].repl_bio
) {
1414 struct md_rdev
*rdev
;
1415 d
= r10_bio
->devs
[j
].devnum
;
1416 rdev
= conf
->mirrors
[d
].replacement
;
1418 /* Race with remove_disk */
1420 rdev
= conf
->mirrors
[d
].rdev
;
1422 rdev_dec_pending(rdev
, mddev
);
1425 allow_barrier(conf
);
1426 md_wait_for_blocked_rdev(blocked_rdev
, mddev
);
1431 if (max_sectors
< r10_bio
->sectors
) {
1432 /* We are splitting this into multiple parts, so
1433 * we need to prepare for allocating another r10_bio.
1435 r10_bio
->sectors
= max_sectors
;
1436 spin_lock_irq(&conf
->device_lock
);
1437 if (bio
->bi_phys_segments
== 0)
1438 bio
->bi_phys_segments
= 2;
1440 bio
->bi_phys_segments
++;
1441 spin_unlock_irq(&conf
->device_lock
);
1443 sectors_handled
= r10_bio
->sector
+ max_sectors
- bio
->bi_sector
;
1445 atomic_set(&r10_bio
->remaining
, 1);
1446 bitmap_startwrite(mddev
->bitmap
, r10_bio
->sector
, r10_bio
->sectors
, 0);
1448 for (i
= 0; i
< conf
->copies
; i
++) {
1450 int d
= r10_bio
->devs
[i
].devnum
;
1451 if (r10_bio
->devs
[i
].bio
) {
1452 struct md_rdev
*rdev
= conf
->mirrors
[d
].rdev
;
1453 mbio
= bio_clone_mddev(bio
, GFP_NOIO
, mddev
);
1454 md_trim_bio(mbio
, r10_bio
->sector
- bio
->bi_sector
,
1456 r10_bio
->devs
[i
].bio
= mbio
;
1458 mbio
->bi_sector
= (r10_bio
->devs
[i
].addr
+
1459 choose_data_offset(r10_bio
,
1461 mbio
->bi_bdev
= rdev
->bdev
;
1462 mbio
->bi_end_io
= raid10_end_write_request
;
1463 mbio
->bi_rw
= WRITE
| do_sync
| do_fua
| do_discard
;
1464 mbio
->bi_private
= r10_bio
;
1466 atomic_inc(&r10_bio
->remaining
);
1468 cb
= blk_check_plugged(raid10_unplug
, mddev
,
1471 plug
= container_of(cb
, struct raid10_plug_cb
,
1475 spin_lock_irqsave(&conf
->device_lock
, flags
);
1477 bio_list_add(&plug
->pending
, mbio
);
1478 plug
->pending_cnt
++;
1480 bio_list_add(&conf
->pending_bio_list
, mbio
);
1481 conf
->pending_count
++;
1483 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
1485 md_wakeup_thread(mddev
->thread
);
1488 if (r10_bio
->devs
[i
].repl_bio
) {
1489 struct md_rdev
*rdev
= conf
->mirrors
[d
].replacement
;
1491 /* Replacement just got moved to main 'rdev' */
1493 rdev
= conf
->mirrors
[d
].rdev
;
1495 mbio
= bio_clone_mddev(bio
, GFP_NOIO
, mddev
);
1496 md_trim_bio(mbio
, r10_bio
->sector
- bio
->bi_sector
,
1498 r10_bio
->devs
[i
].repl_bio
= mbio
;
1500 mbio
->bi_sector
= (r10_bio
->devs
[i
].addr
+
1503 mbio
->bi_bdev
= rdev
->bdev
;
1504 mbio
->bi_end_io
= raid10_end_write_request
;
1505 mbio
->bi_rw
= WRITE
| do_sync
| do_fua
| do_discard
;
1506 mbio
->bi_private
= r10_bio
;
1508 atomic_inc(&r10_bio
->remaining
);
1509 spin_lock_irqsave(&conf
->device_lock
, flags
);
1510 bio_list_add(&conf
->pending_bio_list
, mbio
);
1511 conf
->pending_count
++;
1512 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
1513 if (!mddev_check_plugged(mddev
))
1514 md_wakeup_thread(mddev
->thread
);
1518 /* Don't remove the bias on 'remaining' (one_write_done) until
1519 * after checking if we need to go around again.
1522 if (sectors_handled
< (bio
->bi_size
>> 9)) {
1523 one_write_done(r10_bio
);
1524 /* We need another r10_bio. It has already been counted
1525 * in bio->bi_phys_segments.
1527 r10_bio
= mempool_alloc(conf
->r10bio_pool
, GFP_NOIO
);
1529 r10_bio
->master_bio
= bio
;
1530 r10_bio
->sectors
= (bio
->bi_size
>> 9) - sectors_handled
;
1532 r10_bio
->mddev
= mddev
;
1533 r10_bio
->sector
= bio
->bi_sector
+ sectors_handled
;
1537 one_write_done(r10_bio
);
1539 /* In case raid10d snuck in to freeze_array */
1540 wake_up(&conf
->wait_barrier
);
1543 static void status(struct seq_file
*seq
, struct mddev
*mddev
)
1545 struct r10conf
*conf
= mddev
->private;
1548 if (conf
->geo
.near_copies
< conf
->geo
.raid_disks
)
1549 seq_printf(seq
, " %dK chunks", mddev
->chunk_sectors
/ 2);
1550 if (conf
->geo
.near_copies
> 1)
1551 seq_printf(seq
, " %d near-copies", conf
->geo
.near_copies
);
1552 if (conf
->geo
.far_copies
> 1) {
1553 if (conf
->geo
.far_offset
)
1554 seq_printf(seq
, " %d offset-copies", conf
->geo
.far_copies
);
1556 seq_printf(seq
, " %d far-copies", conf
->geo
.far_copies
);
1558 seq_printf(seq
, " [%d/%d] [", conf
->geo
.raid_disks
,
1559 conf
->geo
.raid_disks
- mddev
->degraded
);
1560 for (i
= 0; i
< conf
->geo
.raid_disks
; i
++)
1561 seq_printf(seq
, "%s",
1562 conf
->mirrors
[i
].rdev
&&
1563 test_bit(In_sync
, &conf
->mirrors
[i
].rdev
->flags
) ? "U" : "_");
1564 seq_printf(seq
, "]");
1567 /* check if there are enough drives for
1568 * every block to appear on atleast one.
1569 * Don't consider the device numbered 'ignore'
1570 * as we might be about to remove it.
1572 static int _enough(struct r10conf
*conf
, struct geom
*geo
, int ignore
)
1577 int n
= conf
->copies
;
1581 if (conf
->mirrors
[this].rdev
&&
1584 this = (this+1) % geo
->raid_disks
;
1588 first
= (first
+ geo
->near_copies
) % geo
->raid_disks
;
1589 } while (first
!= 0);
1593 static int enough(struct r10conf
*conf
, int ignore
)
1595 return _enough(conf
, &conf
->geo
, ignore
) &&
1596 _enough(conf
, &conf
->prev
, ignore
);
1599 static void error(struct mddev
*mddev
, struct md_rdev
*rdev
)
1601 char b
[BDEVNAME_SIZE
];
1602 struct r10conf
*conf
= mddev
->private;
1605 * If it is not operational, then we have already marked it as dead
1606 * else if it is the last working disks, ignore the error, let the
1607 * next level up know.
1608 * else mark the drive as failed
1610 if (test_bit(In_sync
, &rdev
->flags
)
1611 && !enough(conf
, rdev
->raid_disk
))
1613 * Don't fail the drive, just return an IO error.
1616 if (test_and_clear_bit(In_sync
, &rdev
->flags
)) {
1617 unsigned long flags
;
1618 spin_lock_irqsave(&conf
->device_lock
, flags
);
1620 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
1622 * if recovery is running, make sure it aborts.
1624 set_bit(MD_RECOVERY_INTR
, &mddev
->recovery
);
1626 set_bit(Blocked
, &rdev
->flags
);
1627 set_bit(Faulty
, &rdev
->flags
);
1628 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
1630 "md/raid10:%s: Disk failure on %s, disabling device.\n"
1631 "md/raid10:%s: Operation continuing on %d devices.\n",
1632 mdname(mddev
), bdevname(rdev
->bdev
, b
),
1633 mdname(mddev
), conf
->geo
.raid_disks
- mddev
->degraded
);
1636 static void print_conf(struct r10conf
*conf
)
1639 struct raid10_info
*tmp
;
1641 printk(KERN_DEBUG
"RAID10 conf printout:\n");
1643 printk(KERN_DEBUG
"(!conf)\n");
1646 printk(KERN_DEBUG
" --- wd:%d rd:%d\n", conf
->geo
.raid_disks
- conf
->mddev
->degraded
,
1647 conf
->geo
.raid_disks
);
1649 for (i
= 0; i
< conf
->geo
.raid_disks
; i
++) {
1650 char b
[BDEVNAME_SIZE
];
1651 tmp
= conf
->mirrors
+ i
;
1653 printk(KERN_DEBUG
" disk %d, wo:%d, o:%d, dev:%s\n",
1654 i
, !test_bit(In_sync
, &tmp
->rdev
->flags
),
1655 !test_bit(Faulty
, &tmp
->rdev
->flags
),
1656 bdevname(tmp
->rdev
->bdev
,b
));
1660 static void close_sync(struct r10conf
*conf
)
1663 allow_barrier(conf
);
1665 mempool_destroy(conf
->r10buf_pool
);
1666 conf
->r10buf_pool
= NULL
;
1669 static int raid10_spare_active(struct mddev
*mddev
)
1672 struct r10conf
*conf
= mddev
->private;
1673 struct raid10_info
*tmp
;
1675 unsigned long flags
;
1678 * Find all non-in_sync disks within the RAID10 configuration
1679 * and mark them in_sync
1681 for (i
= 0; i
< conf
->geo
.raid_disks
; i
++) {
1682 tmp
= conf
->mirrors
+ i
;
1683 if (tmp
->replacement
1684 && tmp
->replacement
->recovery_offset
== MaxSector
1685 && !test_bit(Faulty
, &tmp
->replacement
->flags
)
1686 && !test_and_set_bit(In_sync
, &tmp
->replacement
->flags
)) {
1687 /* Replacement has just become active */
1689 || !test_and_clear_bit(In_sync
, &tmp
->rdev
->flags
))
1692 /* Replaced device not technically faulty,
1693 * but we need to be sure it gets removed
1694 * and never re-added.
1696 set_bit(Faulty
, &tmp
->rdev
->flags
);
1697 sysfs_notify_dirent_safe(
1698 tmp
->rdev
->sysfs_state
);
1700 sysfs_notify_dirent_safe(tmp
->replacement
->sysfs_state
);
1701 } else if (tmp
->rdev
1702 && !test_bit(Faulty
, &tmp
->rdev
->flags
)
1703 && !test_and_set_bit(In_sync
, &tmp
->rdev
->flags
)) {
1705 sysfs_notify_dirent_safe(tmp
->rdev
->sysfs_state
);
1708 spin_lock_irqsave(&conf
->device_lock
, flags
);
1709 mddev
->degraded
-= count
;
1710 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
1717 static int raid10_add_disk(struct mddev
*mddev
, struct md_rdev
*rdev
)
1719 struct r10conf
*conf
= mddev
->private;
1723 int last
= conf
->geo
.raid_disks
- 1;
1724 struct request_queue
*q
= bdev_get_queue(rdev
->bdev
);
1726 if (mddev
->recovery_cp
< MaxSector
)
1727 /* only hot-add to in-sync arrays, as recovery is
1728 * very different from resync
1731 if (rdev
->saved_raid_disk
< 0 && !_enough(conf
, &conf
->prev
, -1))
1734 if (rdev
->raid_disk
>= 0)
1735 first
= last
= rdev
->raid_disk
;
1737 if (q
->merge_bvec_fn
) {
1738 set_bit(Unmerged
, &rdev
->flags
);
1739 mddev
->merge_check_needed
= 1;
1742 if (rdev
->saved_raid_disk
>= first
&&
1743 conf
->mirrors
[rdev
->saved_raid_disk
].rdev
== NULL
)
1744 mirror
= rdev
->saved_raid_disk
;
1747 for ( ; mirror
<= last
; mirror
++) {
1748 struct raid10_info
*p
= &conf
->mirrors
[mirror
];
1749 if (p
->recovery_disabled
== mddev
->recovery_disabled
)
1752 if (!test_bit(WantReplacement
, &p
->rdev
->flags
) ||
1753 p
->replacement
!= NULL
)
1755 clear_bit(In_sync
, &rdev
->flags
);
1756 set_bit(Replacement
, &rdev
->flags
);
1757 rdev
->raid_disk
= mirror
;
1759 disk_stack_limits(mddev
->gendisk
, rdev
->bdev
,
1760 rdev
->data_offset
<< 9);
1762 rcu_assign_pointer(p
->replacement
, rdev
);
1766 disk_stack_limits(mddev
->gendisk
, rdev
->bdev
,
1767 rdev
->data_offset
<< 9);
1769 p
->head_position
= 0;
1770 p
->recovery_disabled
= mddev
->recovery_disabled
- 1;
1771 rdev
->raid_disk
= mirror
;
1773 if (rdev
->saved_raid_disk
!= mirror
)
1775 rcu_assign_pointer(p
->rdev
, rdev
);
1778 if (err
== 0 && test_bit(Unmerged
, &rdev
->flags
)) {
1779 /* Some requests might not have seen this new
1780 * merge_bvec_fn. We must wait for them to complete
1781 * before merging the device fully.
1782 * First we make sure any code which has tested
1783 * our function has submitted the request, then
1784 * we wait for all outstanding requests to complete.
1786 synchronize_sched();
1787 raise_barrier(conf
, 0);
1788 lower_barrier(conf
);
1789 clear_bit(Unmerged
, &rdev
->flags
);
1791 md_integrity_add_rdev(rdev
, mddev
);
1792 if (mddev
->queue
&& blk_queue_discard(bdev_get_queue(rdev
->bdev
)))
1793 queue_flag_set_unlocked(QUEUE_FLAG_DISCARD
, mddev
->queue
);
1799 static int raid10_remove_disk(struct mddev
*mddev
, struct md_rdev
*rdev
)
1801 struct r10conf
*conf
= mddev
->private;
1803 int number
= rdev
->raid_disk
;
1804 struct md_rdev
**rdevp
;
1805 struct raid10_info
*p
= conf
->mirrors
+ number
;
1808 if (rdev
== p
->rdev
)
1810 else if (rdev
== p
->replacement
)
1811 rdevp
= &p
->replacement
;
1815 if (test_bit(In_sync
, &rdev
->flags
) ||
1816 atomic_read(&rdev
->nr_pending
)) {
1820 /* Only remove faulty devices if recovery
1823 if (!test_bit(Faulty
, &rdev
->flags
) &&
1824 mddev
->recovery_disabled
!= p
->recovery_disabled
&&
1825 (!p
->replacement
|| p
->replacement
== rdev
) &&
1826 number
< conf
->geo
.raid_disks
&&
1833 if (atomic_read(&rdev
->nr_pending
)) {
1834 /* lost the race, try later */
1838 } else if (p
->replacement
) {
1839 /* We must have just cleared 'rdev' */
1840 p
->rdev
= p
->replacement
;
1841 clear_bit(Replacement
, &p
->replacement
->flags
);
1842 smp_mb(); /* Make sure other CPUs may see both as identical
1843 * but will never see neither -- if they are careful.
1845 p
->replacement
= NULL
;
1846 clear_bit(WantReplacement
, &rdev
->flags
);
1848 /* We might have just remove the Replacement as faulty
1849 * Clear the flag just in case
1851 clear_bit(WantReplacement
, &rdev
->flags
);
1853 err
= md_integrity_register(mddev
);
1862 static void end_sync_read(struct bio
*bio
, int error
)
1864 struct r10bio
*r10_bio
= bio
->bi_private
;
1865 struct r10conf
*conf
= r10_bio
->mddev
->private;
1868 if (bio
== r10_bio
->master_bio
) {
1869 /* this is a reshape read */
1870 d
= r10_bio
->read_slot
; /* really the read dev */
1872 d
= find_bio_disk(conf
, r10_bio
, bio
, NULL
, NULL
);
1874 if (test_bit(BIO_UPTODATE
, &bio
->bi_flags
))
1875 set_bit(R10BIO_Uptodate
, &r10_bio
->state
);
1877 /* The write handler will notice the lack of
1878 * R10BIO_Uptodate and record any errors etc
1880 atomic_add(r10_bio
->sectors
,
1881 &conf
->mirrors
[d
].rdev
->corrected_errors
);
1883 /* for reconstruct, we always reschedule after a read.
1884 * for resync, only after all reads
1886 rdev_dec_pending(conf
->mirrors
[d
].rdev
, conf
->mddev
);
1887 if (test_bit(R10BIO_IsRecover
, &r10_bio
->state
) ||
1888 atomic_dec_and_test(&r10_bio
->remaining
)) {
1889 /* we have read all the blocks,
1890 * do the comparison in process context in raid10d
1892 reschedule_retry(r10_bio
);
1896 static void end_sync_request(struct r10bio
*r10_bio
)
1898 struct mddev
*mddev
= r10_bio
->mddev
;
1900 while (atomic_dec_and_test(&r10_bio
->remaining
)) {
1901 if (r10_bio
->master_bio
== NULL
) {
1902 /* the primary of several recovery bios */
1903 sector_t s
= r10_bio
->sectors
;
1904 if (test_bit(R10BIO_MadeGood
, &r10_bio
->state
) ||
1905 test_bit(R10BIO_WriteError
, &r10_bio
->state
))
1906 reschedule_retry(r10_bio
);
1909 md_done_sync(mddev
, s
, 1);
1912 struct r10bio
*r10_bio2
= (struct r10bio
*)r10_bio
->master_bio
;
1913 if (test_bit(R10BIO_MadeGood
, &r10_bio
->state
) ||
1914 test_bit(R10BIO_WriteError
, &r10_bio
->state
))
1915 reschedule_retry(r10_bio
);
1923 static void end_sync_write(struct bio
*bio
, int error
)
1925 int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
1926 struct r10bio
*r10_bio
= bio
->bi_private
;
1927 struct mddev
*mddev
= r10_bio
->mddev
;
1928 struct r10conf
*conf
= mddev
->private;
1934 struct md_rdev
*rdev
= NULL
;
1936 d
= find_bio_disk(conf
, r10_bio
, bio
, &slot
, &repl
);
1938 rdev
= conf
->mirrors
[d
].replacement
;
1940 rdev
= conf
->mirrors
[d
].rdev
;
1944 md_error(mddev
, rdev
);
1946 set_bit(WriteErrorSeen
, &rdev
->flags
);
1947 if (!test_and_set_bit(WantReplacement
, &rdev
->flags
))
1948 set_bit(MD_RECOVERY_NEEDED
,
1949 &rdev
->mddev
->recovery
);
1950 set_bit(R10BIO_WriteError
, &r10_bio
->state
);
1952 } else if (is_badblock(rdev
,
1953 r10_bio
->devs
[slot
].addr
,
1955 &first_bad
, &bad_sectors
))
1956 set_bit(R10BIO_MadeGood
, &r10_bio
->state
);
1958 rdev_dec_pending(rdev
, mddev
);
1960 end_sync_request(r10_bio
);
1964 * Note: sync and recover and handled very differently for raid10
1965 * This code is for resync.
1966 * For resync, we read through virtual addresses and read all blocks.
1967 * If there is any error, we schedule a write. The lowest numbered
1968 * drive is authoritative.
1969 * However requests come for physical address, so we need to map.
1970 * For every physical address there are raid_disks/copies virtual addresses,
1971 * which is always are least one, but is not necessarly an integer.
1972 * This means that a physical address can span multiple chunks, so we may
1973 * have to submit multiple io requests for a single sync request.
1976 * We check if all blocks are in-sync and only write to blocks that
1979 static void sync_request_write(struct mddev
*mddev
, struct r10bio
*r10_bio
)
1981 struct r10conf
*conf
= mddev
->private;
1983 struct bio
*tbio
, *fbio
;
1986 atomic_set(&r10_bio
->remaining
, 1);
1988 /* find the first device with a block */
1989 for (i
=0; i
<conf
->copies
; i
++)
1990 if (test_bit(BIO_UPTODATE
, &r10_bio
->devs
[i
].bio
->bi_flags
))
1993 if (i
== conf
->copies
)
1997 fbio
= r10_bio
->devs
[i
].bio
;
1999 vcnt
= (r10_bio
->sectors
+ (PAGE_SIZE
>> 9) - 1) >> (PAGE_SHIFT
- 9);
2000 /* now find blocks with errors */
2001 for (i
=0 ; i
< conf
->copies
; i
++) {
2004 tbio
= r10_bio
->devs
[i
].bio
;
2006 if (tbio
->bi_end_io
!= end_sync_read
)
2010 if (test_bit(BIO_UPTODATE
, &r10_bio
->devs
[i
].bio
->bi_flags
)) {
2011 /* We know that the bi_io_vec layout is the same for
2012 * both 'first' and 'i', so we just compare them.
2013 * All vec entries are PAGE_SIZE;
2015 for (j
= 0; j
< vcnt
; j
++)
2016 if (memcmp(page_address(fbio
->bi_io_vec
[j
].bv_page
),
2017 page_address(tbio
->bi_io_vec
[j
].bv_page
),
2018 fbio
->bi_io_vec
[j
].bv_len
))
2022 atomic64_add(r10_bio
->sectors
, &mddev
->resync_mismatches
);
2023 if (test_bit(MD_RECOVERY_CHECK
, &mddev
->recovery
))
2024 /* Don't fix anything. */
2027 /* Ok, we need to write this bio, either to correct an
2028 * inconsistency or to correct an unreadable block.
2029 * First we need to fixup bv_offset, bv_len and
2030 * bi_vecs, as the read request might have corrupted these
2032 tbio
->bi_vcnt
= vcnt
;
2033 tbio
->bi_size
= r10_bio
->sectors
<< 9;
2035 tbio
->bi_phys_segments
= 0;
2036 tbio
->bi_flags
&= ~(BIO_POOL_MASK
- 1);
2037 tbio
->bi_flags
|= 1 << BIO_UPTODATE
;
2038 tbio
->bi_next
= NULL
;
2039 tbio
->bi_rw
= WRITE
;
2040 tbio
->bi_private
= r10_bio
;
2041 tbio
->bi_sector
= r10_bio
->devs
[i
].addr
;
2043 for (j
=0; j
< vcnt
; j
++) {
2044 tbio
->bi_io_vec
[j
].bv_offset
= 0;
2045 tbio
->bi_io_vec
[j
].bv_len
= PAGE_SIZE
;
2047 memcpy(page_address(tbio
->bi_io_vec
[j
].bv_page
),
2048 page_address(fbio
->bi_io_vec
[j
].bv_page
),
2051 tbio
->bi_end_io
= end_sync_write
;
2053 d
= r10_bio
->devs
[i
].devnum
;
2054 atomic_inc(&conf
->mirrors
[d
].rdev
->nr_pending
);
2055 atomic_inc(&r10_bio
->remaining
);
2056 md_sync_acct(conf
->mirrors
[d
].rdev
->bdev
, tbio
->bi_size
>> 9);
2058 tbio
->bi_sector
+= conf
->mirrors
[d
].rdev
->data_offset
;
2059 tbio
->bi_bdev
= conf
->mirrors
[d
].rdev
->bdev
;
2060 generic_make_request(tbio
);
2063 /* Now write out to any replacement devices
2066 for (i
= 0; i
< conf
->copies
; i
++) {
2069 tbio
= r10_bio
->devs
[i
].repl_bio
;
2070 if (!tbio
|| !tbio
->bi_end_io
)
2072 if (r10_bio
->devs
[i
].bio
->bi_end_io
!= end_sync_write
2073 && r10_bio
->devs
[i
].bio
!= fbio
)
2074 for (j
= 0; j
< vcnt
; j
++)
2075 memcpy(page_address(tbio
->bi_io_vec
[j
].bv_page
),
2076 page_address(fbio
->bi_io_vec
[j
].bv_page
),
2078 d
= r10_bio
->devs
[i
].devnum
;
2079 atomic_inc(&r10_bio
->remaining
);
2080 md_sync_acct(conf
->mirrors
[d
].replacement
->bdev
,
2081 tbio
->bi_size
>> 9);
2082 generic_make_request(tbio
);
2086 if (atomic_dec_and_test(&r10_bio
->remaining
)) {
2087 md_done_sync(mddev
, r10_bio
->sectors
, 1);
2093 * Now for the recovery code.
2094 * Recovery happens across physical sectors.
2095 * We recover all non-is_sync drives by finding the virtual address of
2096 * each, and then choose a working drive that also has that virt address.
2097 * There is a separate r10_bio for each non-in_sync drive.
2098 * Only the first two slots are in use. The first for reading,
2099 * The second for writing.
2102 static void fix_recovery_read_error(struct r10bio
*r10_bio
)
2104 /* We got a read error during recovery.
2105 * We repeat the read in smaller page-sized sections.
2106 * If a read succeeds, write it to the new device or record
2107 * a bad block if we cannot.
2108 * If a read fails, record a bad block on both old and
2111 struct mddev
*mddev
= r10_bio
->mddev
;
2112 struct r10conf
*conf
= mddev
->private;
2113 struct bio
*bio
= r10_bio
->devs
[0].bio
;
2115 int sectors
= r10_bio
->sectors
;
2117 int dr
= r10_bio
->devs
[0].devnum
;
2118 int dw
= r10_bio
->devs
[1].devnum
;
2122 struct md_rdev
*rdev
;
2126 if (s
> (PAGE_SIZE
>>9))
2129 rdev
= conf
->mirrors
[dr
].rdev
;
2130 addr
= r10_bio
->devs
[0].addr
+ sect
,
2131 ok
= sync_page_io(rdev
,
2134 bio
->bi_io_vec
[idx
].bv_page
,
2137 rdev
= conf
->mirrors
[dw
].rdev
;
2138 addr
= r10_bio
->devs
[1].addr
+ sect
;
2139 ok
= sync_page_io(rdev
,
2142 bio
->bi_io_vec
[idx
].bv_page
,
2145 set_bit(WriteErrorSeen
, &rdev
->flags
);
2146 if (!test_and_set_bit(WantReplacement
,
2148 set_bit(MD_RECOVERY_NEEDED
,
2149 &rdev
->mddev
->recovery
);
2153 /* We don't worry if we cannot set a bad block -
2154 * it really is bad so there is no loss in not
2157 rdev_set_badblocks(rdev
, addr
, s
, 0);
2159 if (rdev
!= conf
->mirrors
[dw
].rdev
) {
2160 /* need bad block on destination too */
2161 struct md_rdev
*rdev2
= conf
->mirrors
[dw
].rdev
;
2162 addr
= r10_bio
->devs
[1].addr
+ sect
;
2163 ok
= rdev_set_badblocks(rdev2
, addr
, s
, 0);
2165 /* just abort the recovery */
2167 "md/raid10:%s: recovery aborted"
2168 " due to read error\n",
2171 conf
->mirrors
[dw
].recovery_disabled
2172 = mddev
->recovery_disabled
;
2173 set_bit(MD_RECOVERY_INTR
,
2186 static void recovery_request_write(struct mddev
*mddev
, struct r10bio
*r10_bio
)
2188 struct r10conf
*conf
= mddev
->private;
2190 struct bio
*wbio
, *wbio2
;
2192 if (!test_bit(R10BIO_Uptodate
, &r10_bio
->state
)) {
2193 fix_recovery_read_error(r10_bio
);
2194 end_sync_request(r10_bio
);
2199 * share the pages with the first bio
2200 * and submit the write request
2202 d
= r10_bio
->devs
[1].devnum
;
2203 wbio
= r10_bio
->devs
[1].bio
;
2204 wbio2
= r10_bio
->devs
[1].repl_bio
;
2205 if (wbio
->bi_end_io
) {
2206 atomic_inc(&conf
->mirrors
[d
].rdev
->nr_pending
);
2207 md_sync_acct(conf
->mirrors
[d
].rdev
->bdev
, wbio
->bi_size
>> 9);
2208 generic_make_request(wbio
);
2210 if (wbio2
&& wbio2
->bi_end_io
) {
2211 atomic_inc(&conf
->mirrors
[d
].replacement
->nr_pending
);
2212 md_sync_acct(conf
->mirrors
[d
].replacement
->bdev
,
2213 wbio2
->bi_size
>> 9);
2214 generic_make_request(wbio2
);
2220 * Used by fix_read_error() to decay the per rdev read_errors.
2221 * We halve the read error count for every hour that has elapsed
2222 * since the last recorded read error.
2225 static void check_decay_read_errors(struct mddev
*mddev
, struct md_rdev
*rdev
)
2227 struct timespec cur_time_mon
;
2228 unsigned long hours_since_last
;
2229 unsigned int read_errors
= atomic_read(&rdev
->read_errors
);
2231 ktime_get_ts(&cur_time_mon
);
2233 if (rdev
->last_read_error
.tv_sec
== 0 &&
2234 rdev
->last_read_error
.tv_nsec
== 0) {
2235 /* first time we've seen a read error */
2236 rdev
->last_read_error
= cur_time_mon
;
2240 hours_since_last
= (cur_time_mon
.tv_sec
-
2241 rdev
->last_read_error
.tv_sec
) / 3600;
2243 rdev
->last_read_error
= cur_time_mon
;
2246 * if hours_since_last is > the number of bits in read_errors
2247 * just set read errors to 0. We do this to avoid
2248 * overflowing the shift of read_errors by hours_since_last.
2250 if (hours_since_last
>= 8 * sizeof(read_errors
))
2251 atomic_set(&rdev
->read_errors
, 0);
2253 atomic_set(&rdev
->read_errors
, read_errors
>> hours_since_last
);
2256 static int r10_sync_page_io(struct md_rdev
*rdev
, sector_t sector
,
2257 int sectors
, struct page
*page
, int rw
)
2262 if (is_badblock(rdev
, sector
, sectors
, &first_bad
, &bad_sectors
)
2263 && (rw
== READ
|| test_bit(WriteErrorSeen
, &rdev
->flags
)))
2265 if (sync_page_io(rdev
, sector
, sectors
<< 9, page
, rw
, false))
2269 set_bit(WriteErrorSeen
, &rdev
->flags
);
2270 if (!test_and_set_bit(WantReplacement
, &rdev
->flags
))
2271 set_bit(MD_RECOVERY_NEEDED
,
2272 &rdev
->mddev
->recovery
);
2274 /* need to record an error - either for the block or the device */
2275 if (!rdev_set_badblocks(rdev
, sector
, sectors
, 0))
2276 md_error(rdev
->mddev
, rdev
);
2281 * This is a kernel thread which:
2283 * 1. Retries failed read operations on working mirrors.
2284 * 2. Updates the raid superblock when problems encounter.
2285 * 3. Performs writes following reads for array synchronising.
2288 static void fix_read_error(struct r10conf
*conf
, struct mddev
*mddev
, struct r10bio
*r10_bio
)
2290 int sect
= 0; /* Offset from r10_bio->sector */
2291 int sectors
= r10_bio
->sectors
;
2292 struct md_rdev
*rdev
;
2293 int max_read_errors
= atomic_read(&mddev
->max_corr_read_errors
);
2294 int d
= r10_bio
->devs
[r10_bio
->read_slot
].devnum
;
2296 /* still own a reference to this rdev, so it cannot
2297 * have been cleared recently.
2299 rdev
= conf
->mirrors
[d
].rdev
;
2301 if (test_bit(Faulty
, &rdev
->flags
))
2302 /* drive has already been failed, just ignore any
2303 more fix_read_error() attempts */
2306 check_decay_read_errors(mddev
, rdev
);
2307 atomic_inc(&rdev
->read_errors
);
2308 if (atomic_read(&rdev
->read_errors
) > max_read_errors
) {
2309 char b
[BDEVNAME_SIZE
];
2310 bdevname(rdev
->bdev
, b
);
2313 "md/raid10:%s: %s: Raid device exceeded "
2314 "read_error threshold [cur %d:max %d]\n",
2316 atomic_read(&rdev
->read_errors
), max_read_errors
);
2318 "md/raid10:%s: %s: Failing raid device\n",
2320 md_error(mddev
, conf
->mirrors
[d
].rdev
);
2321 r10_bio
->devs
[r10_bio
->read_slot
].bio
= IO_BLOCKED
;
2327 int sl
= r10_bio
->read_slot
;
2331 if (s
> (PAGE_SIZE
>>9))
2339 d
= r10_bio
->devs
[sl
].devnum
;
2340 rdev
= rcu_dereference(conf
->mirrors
[d
].rdev
);
2342 !test_bit(Unmerged
, &rdev
->flags
) &&
2343 test_bit(In_sync
, &rdev
->flags
) &&
2344 is_badblock(rdev
, r10_bio
->devs
[sl
].addr
+ sect
, s
,
2345 &first_bad
, &bad_sectors
) == 0) {
2346 atomic_inc(&rdev
->nr_pending
);
2348 success
= sync_page_io(rdev
,
2349 r10_bio
->devs
[sl
].addr
+
2352 conf
->tmppage
, READ
, false);
2353 rdev_dec_pending(rdev
, mddev
);
2359 if (sl
== conf
->copies
)
2361 } while (!success
&& sl
!= r10_bio
->read_slot
);
2365 /* Cannot read from anywhere, just mark the block
2366 * as bad on the first device to discourage future
2369 int dn
= r10_bio
->devs
[r10_bio
->read_slot
].devnum
;
2370 rdev
= conf
->mirrors
[dn
].rdev
;
2372 if (!rdev_set_badblocks(
2374 r10_bio
->devs
[r10_bio
->read_slot
].addr
2377 md_error(mddev
, rdev
);
2378 r10_bio
->devs
[r10_bio
->read_slot
].bio
2385 /* write it back and re-read */
2387 while (sl
!= r10_bio
->read_slot
) {
2388 char b
[BDEVNAME_SIZE
];
2393 d
= r10_bio
->devs
[sl
].devnum
;
2394 rdev
= rcu_dereference(conf
->mirrors
[d
].rdev
);
2396 test_bit(Unmerged
, &rdev
->flags
) ||
2397 !test_bit(In_sync
, &rdev
->flags
))
2400 atomic_inc(&rdev
->nr_pending
);
2402 if (r10_sync_page_io(rdev
,
2403 r10_bio
->devs
[sl
].addr
+
2405 s
, conf
->tmppage
, WRITE
)
2407 /* Well, this device is dead */
2409 "md/raid10:%s: read correction "
2411 " (%d sectors at %llu on %s)\n",
2413 (unsigned long long)(
2415 choose_data_offset(r10_bio
,
2417 bdevname(rdev
->bdev
, b
));
2418 printk(KERN_NOTICE
"md/raid10:%s: %s: failing "
2421 bdevname(rdev
->bdev
, b
));
2423 rdev_dec_pending(rdev
, mddev
);
2427 while (sl
!= r10_bio
->read_slot
) {
2428 char b
[BDEVNAME_SIZE
];
2433 d
= r10_bio
->devs
[sl
].devnum
;
2434 rdev
= rcu_dereference(conf
->mirrors
[d
].rdev
);
2436 !test_bit(In_sync
, &rdev
->flags
))
2439 atomic_inc(&rdev
->nr_pending
);
2441 switch (r10_sync_page_io(rdev
,
2442 r10_bio
->devs
[sl
].addr
+
2447 /* Well, this device is dead */
2449 "md/raid10:%s: unable to read back "
2451 " (%d sectors at %llu on %s)\n",
2453 (unsigned long long)(
2455 choose_data_offset(r10_bio
, rdev
)),
2456 bdevname(rdev
->bdev
, b
));
2457 printk(KERN_NOTICE
"md/raid10:%s: %s: failing "
2460 bdevname(rdev
->bdev
, b
));
2464 "md/raid10:%s: read error corrected"
2465 " (%d sectors at %llu on %s)\n",
2467 (unsigned long long)(
2469 choose_data_offset(r10_bio
, rdev
)),
2470 bdevname(rdev
->bdev
, b
));
2471 atomic_add(s
, &rdev
->corrected_errors
);
2474 rdev_dec_pending(rdev
, mddev
);
2484 static void bi_complete(struct bio
*bio
, int error
)
2486 complete((struct completion
*)bio
->bi_private
);
2489 static int submit_bio_wait(int rw
, struct bio
*bio
)
2491 struct completion event
;
2494 init_completion(&event
);
2495 bio
->bi_private
= &event
;
2496 bio
->bi_end_io
= bi_complete
;
2497 submit_bio(rw
, bio
);
2498 wait_for_completion(&event
);
2500 return test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
2503 static int narrow_write_error(struct r10bio
*r10_bio
, int i
)
2505 struct bio
*bio
= r10_bio
->master_bio
;
2506 struct mddev
*mddev
= r10_bio
->mddev
;
2507 struct r10conf
*conf
= mddev
->private;
2508 struct md_rdev
*rdev
= conf
->mirrors
[r10_bio
->devs
[i
].devnum
].rdev
;
2509 /* bio has the data to be written to slot 'i' where
2510 * we just recently had a write error.
2511 * We repeatedly clone the bio and trim down to one block,
2512 * then try the write. Where the write fails we record
2514 * It is conceivable that the bio doesn't exactly align with
2515 * blocks. We must handle this.
2517 * We currently own a reference to the rdev.
2523 int sect_to_write
= r10_bio
->sectors
;
2526 if (rdev
->badblocks
.shift
< 0)
2529 block_sectors
= 1 << rdev
->badblocks
.shift
;
2530 sector
= r10_bio
->sector
;
2531 sectors
= ((r10_bio
->sector
+ block_sectors
)
2532 & ~(sector_t
)(block_sectors
- 1))
2535 while (sect_to_write
) {
2537 if (sectors
> sect_to_write
)
2538 sectors
= sect_to_write
;
2539 /* Write at 'sector' for 'sectors' */
2540 wbio
= bio_clone_mddev(bio
, GFP_NOIO
, mddev
);
2541 md_trim_bio(wbio
, sector
- bio
->bi_sector
, sectors
);
2542 wbio
->bi_sector
= (r10_bio
->devs
[i
].addr
+
2543 choose_data_offset(r10_bio
, rdev
) +
2544 (sector
- r10_bio
->sector
));
2545 wbio
->bi_bdev
= rdev
->bdev
;
2546 if (submit_bio_wait(WRITE
, wbio
) == 0)
2548 ok
= rdev_set_badblocks(rdev
, sector
,
2553 sect_to_write
-= sectors
;
2555 sectors
= block_sectors
;
2560 static void handle_read_error(struct mddev
*mddev
, struct r10bio
*r10_bio
)
2562 int slot
= r10_bio
->read_slot
;
2564 struct r10conf
*conf
= mddev
->private;
2565 struct md_rdev
*rdev
= r10_bio
->devs
[slot
].rdev
;
2566 char b
[BDEVNAME_SIZE
];
2567 unsigned long do_sync
;
2570 /* we got a read error. Maybe the drive is bad. Maybe just
2571 * the block and we can fix it.
2572 * We freeze all other IO, and try reading the block from
2573 * other devices. When we find one, we re-write
2574 * and check it that fixes the read error.
2575 * This is all done synchronously while the array is
2578 bio
= r10_bio
->devs
[slot
].bio
;
2579 bdevname(bio
->bi_bdev
, b
);
2581 r10_bio
->devs
[slot
].bio
= NULL
;
2583 if (mddev
->ro
== 0) {
2585 fix_read_error(conf
, mddev
, r10_bio
);
2586 unfreeze_array(conf
);
2588 r10_bio
->devs
[slot
].bio
= IO_BLOCKED
;
2590 rdev_dec_pending(rdev
, mddev
);
2593 rdev
= read_balance(conf
, r10_bio
, &max_sectors
);
2595 printk(KERN_ALERT
"md/raid10:%s: %s: unrecoverable I/O"
2596 " read error for block %llu\n",
2598 (unsigned long long)r10_bio
->sector
);
2599 raid_end_bio_io(r10_bio
);
2603 do_sync
= (r10_bio
->master_bio
->bi_rw
& REQ_SYNC
);
2604 slot
= r10_bio
->read_slot
;
2607 "md/raid10:%s: %s: redirecting "
2608 "sector %llu to another mirror\n",
2610 bdevname(rdev
->bdev
, b
),
2611 (unsigned long long)r10_bio
->sector
);
2612 bio
= bio_clone_mddev(r10_bio
->master_bio
,
2615 r10_bio
->sector
- bio
->bi_sector
,
2617 r10_bio
->devs
[slot
].bio
= bio
;
2618 r10_bio
->devs
[slot
].rdev
= rdev
;
2619 bio
->bi_sector
= r10_bio
->devs
[slot
].addr
2620 + choose_data_offset(r10_bio
, rdev
);
2621 bio
->bi_bdev
= rdev
->bdev
;
2622 bio
->bi_rw
= READ
| do_sync
;
2623 bio
->bi_private
= r10_bio
;
2624 bio
->bi_end_io
= raid10_end_read_request
;
2625 if (max_sectors
< r10_bio
->sectors
) {
2626 /* Drat - have to split this up more */
2627 struct bio
*mbio
= r10_bio
->master_bio
;
2628 int sectors_handled
=
2629 r10_bio
->sector
+ max_sectors
2631 r10_bio
->sectors
= max_sectors
;
2632 spin_lock_irq(&conf
->device_lock
);
2633 if (mbio
->bi_phys_segments
== 0)
2634 mbio
->bi_phys_segments
= 2;
2636 mbio
->bi_phys_segments
++;
2637 spin_unlock_irq(&conf
->device_lock
);
2638 generic_make_request(bio
);
2640 r10_bio
= mempool_alloc(conf
->r10bio_pool
,
2642 r10_bio
->master_bio
= mbio
;
2643 r10_bio
->sectors
= (mbio
->bi_size
>> 9)
2646 set_bit(R10BIO_ReadError
,
2648 r10_bio
->mddev
= mddev
;
2649 r10_bio
->sector
= mbio
->bi_sector
2654 generic_make_request(bio
);
2657 static void handle_write_completed(struct r10conf
*conf
, struct r10bio
*r10_bio
)
2659 /* Some sort of write request has finished and it
2660 * succeeded in writing where we thought there was a
2661 * bad block. So forget the bad block.
2662 * Or possibly if failed and we need to record
2666 struct md_rdev
*rdev
;
2668 if (test_bit(R10BIO_IsSync
, &r10_bio
->state
) ||
2669 test_bit(R10BIO_IsRecover
, &r10_bio
->state
)) {
2670 for (m
= 0; m
< conf
->copies
; m
++) {
2671 int dev
= r10_bio
->devs
[m
].devnum
;
2672 rdev
= conf
->mirrors
[dev
].rdev
;
2673 if (r10_bio
->devs
[m
].bio
== NULL
)
2675 if (test_bit(BIO_UPTODATE
,
2676 &r10_bio
->devs
[m
].bio
->bi_flags
)) {
2677 rdev_clear_badblocks(
2679 r10_bio
->devs
[m
].addr
,
2680 r10_bio
->sectors
, 0);
2682 if (!rdev_set_badblocks(
2684 r10_bio
->devs
[m
].addr
,
2685 r10_bio
->sectors
, 0))
2686 md_error(conf
->mddev
, rdev
);
2688 rdev
= conf
->mirrors
[dev
].replacement
;
2689 if (r10_bio
->devs
[m
].repl_bio
== NULL
)
2691 if (test_bit(BIO_UPTODATE
,
2692 &r10_bio
->devs
[m
].repl_bio
->bi_flags
)) {
2693 rdev_clear_badblocks(
2695 r10_bio
->devs
[m
].addr
,
2696 r10_bio
->sectors
, 0);
2698 if (!rdev_set_badblocks(
2700 r10_bio
->devs
[m
].addr
,
2701 r10_bio
->sectors
, 0))
2702 md_error(conf
->mddev
, rdev
);
2707 for (m
= 0; m
< conf
->copies
; m
++) {
2708 int dev
= r10_bio
->devs
[m
].devnum
;
2709 struct bio
*bio
= r10_bio
->devs
[m
].bio
;
2710 rdev
= conf
->mirrors
[dev
].rdev
;
2711 if (bio
== IO_MADE_GOOD
) {
2712 rdev_clear_badblocks(
2714 r10_bio
->devs
[m
].addr
,
2715 r10_bio
->sectors
, 0);
2716 rdev_dec_pending(rdev
, conf
->mddev
);
2717 } else if (bio
!= NULL
&&
2718 !test_bit(BIO_UPTODATE
, &bio
->bi_flags
)) {
2719 if (!narrow_write_error(r10_bio
, m
)) {
2720 md_error(conf
->mddev
, rdev
);
2721 set_bit(R10BIO_Degraded
,
2724 rdev_dec_pending(rdev
, conf
->mddev
);
2726 bio
= r10_bio
->devs
[m
].repl_bio
;
2727 rdev
= conf
->mirrors
[dev
].replacement
;
2728 if (rdev
&& bio
== IO_MADE_GOOD
) {
2729 rdev_clear_badblocks(
2731 r10_bio
->devs
[m
].addr
,
2732 r10_bio
->sectors
, 0);
2733 rdev_dec_pending(rdev
, conf
->mddev
);
2736 if (test_bit(R10BIO_WriteError
,
2738 close_write(r10_bio
);
2739 raid_end_bio_io(r10_bio
);
2743 static void raid10d(struct md_thread
*thread
)
2745 struct mddev
*mddev
= thread
->mddev
;
2746 struct r10bio
*r10_bio
;
2747 unsigned long flags
;
2748 struct r10conf
*conf
= mddev
->private;
2749 struct list_head
*head
= &conf
->retry_list
;
2750 struct blk_plug plug
;
2752 md_check_recovery(mddev
);
2754 blk_start_plug(&plug
);
2757 flush_pending_writes(conf
);
2759 spin_lock_irqsave(&conf
->device_lock
, flags
);
2760 if (list_empty(head
)) {
2761 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
2764 r10_bio
= list_entry(head
->prev
, struct r10bio
, retry_list
);
2765 list_del(head
->prev
);
2767 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
2769 mddev
= r10_bio
->mddev
;
2770 conf
= mddev
->private;
2771 if (test_bit(R10BIO_MadeGood
, &r10_bio
->state
) ||
2772 test_bit(R10BIO_WriteError
, &r10_bio
->state
))
2773 handle_write_completed(conf
, r10_bio
);
2774 else if (test_bit(R10BIO_IsReshape
, &r10_bio
->state
))
2775 reshape_request_write(mddev
, r10_bio
);
2776 else if (test_bit(R10BIO_IsSync
, &r10_bio
->state
))
2777 sync_request_write(mddev
, r10_bio
);
2778 else if (test_bit(R10BIO_IsRecover
, &r10_bio
->state
))
2779 recovery_request_write(mddev
, r10_bio
);
2780 else if (test_bit(R10BIO_ReadError
, &r10_bio
->state
))
2781 handle_read_error(mddev
, r10_bio
);
2783 /* just a partial read to be scheduled from a
2786 int slot
= r10_bio
->read_slot
;
2787 generic_make_request(r10_bio
->devs
[slot
].bio
);
2791 if (mddev
->flags
& ~(1<<MD_CHANGE_PENDING
))
2792 md_check_recovery(mddev
);
2794 blk_finish_plug(&plug
);
2798 static int init_resync(struct r10conf
*conf
)
2803 buffs
= RESYNC_WINDOW
/ RESYNC_BLOCK_SIZE
;
2804 BUG_ON(conf
->r10buf_pool
);
2805 conf
->have_replacement
= 0;
2806 for (i
= 0; i
< conf
->geo
.raid_disks
; i
++)
2807 if (conf
->mirrors
[i
].replacement
)
2808 conf
->have_replacement
= 1;
2809 conf
->r10buf_pool
= mempool_create(buffs
, r10buf_pool_alloc
, r10buf_pool_free
, conf
);
2810 if (!conf
->r10buf_pool
)
2812 conf
->next_resync
= 0;
2817 * perform a "sync" on one "block"
2819 * We need to make sure that no normal I/O request - particularly write
2820 * requests - conflict with active sync requests.
2822 * This is achieved by tracking pending requests and a 'barrier' concept
2823 * that can be installed to exclude normal IO requests.
2825 * Resync and recovery are handled very differently.
2826 * We differentiate by looking at MD_RECOVERY_SYNC in mddev->recovery.
2828 * For resync, we iterate over virtual addresses, read all copies,
2829 * and update if there are differences. If only one copy is live,
2831 * For recovery, we iterate over physical addresses, read a good
2832 * value for each non-in_sync drive, and over-write.
2834 * So, for recovery we may have several outstanding complex requests for a
2835 * given address, one for each out-of-sync device. We model this by allocating
2836 * a number of r10_bio structures, one for each out-of-sync device.
2837 * As we setup these structures, we collect all bio's together into a list
2838 * which we then process collectively to add pages, and then process again
2839 * to pass to generic_make_request.
2841 * The r10_bio structures are linked using a borrowed master_bio pointer.
2842 * This link is counted in ->remaining. When the r10_bio that points to NULL
2843 * has its remaining count decremented to 0, the whole complex operation
2848 static sector_t
sync_request(struct mddev
*mddev
, sector_t sector_nr
,
2849 int *skipped
, int go_faster
)
2851 struct r10conf
*conf
= mddev
->private;
2852 struct r10bio
*r10_bio
;
2853 struct bio
*biolist
= NULL
, *bio
;
2854 sector_t max_sector
, nr_sectors
;
2857 sector_t sync_blocks
;
2858 sector_t sectors_skipped
= 0;
2859 int chunks_skipped
= 0;
2860 sector_t chunk_mask
= conf
->geo
.chunk_mask
;
2862 if (!conf
->r10buf_pool
)
2863 if (init_resync(conf
))
2867 max_sector
= mddev
->dev_sectors
;
2868 if (test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
) ||
2869 test_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
))
2870 max_sector
= mddev
->resync_max_sectors
;
2871 if (sector_nr
>= max_sector
) {
2872 /* If we aborted, we need to abort the
2873 * sync on the 'current' bitmap chucks (there can
2874 * be several when recovering multiple devices).
2875 * as we may have started syncing it but not finished.
2876 * We can find the current address in
2877 * mddev->curr_resync, but for recovery,
2878 * we need to convert that to several
2879 * virtual addresses.
2881 if (test_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
)) {
2886 if (mddev
->curr_resync
< max_sector
) { /* aborted */
2887 if (test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
))
2888 bitmap_end_sync(mddev
->bitmap
, mddev
->curr_resync
,
2890 else for (i
= 0; i
< conf
->geo
.raid_disks
; i
++) {
2892 raid10_find_virt(conf
, mddev
->curr_resync
, i
);
2893 bitmap_end_sync(mddev
->bitmap
, sect
,
2897 /* completed sync */
2898 if ((!mddev
->bitmap
|| conf
->fullsync
)
2899 && conf
->have_replacement
2900 && test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
)) {
2901 /* Completed a full sync so the replacements
2902 * are now fully recovered.
2904 for (i
= 0; i
< conf
->geo
.raid_disks
; i
++)
2905 if (conf
->mirrors
[i
].replacement
)
2906 conf
->mirrors
[i
].replacement
2912 bitmap_close_sync(mddev
->bitmap
);
2915 return sectors_skipped
;
2918 if (test_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
))
2919 return reshape_request(mddev
, sector_nr
, skipped
);
2921 if (chunks_skipped
>= conf
->geo
.raid_disks
) {
2922 /* if there has been nothing to do on any drive,
2923 * then there is nothing to do at all..
2926 return (max_sector
- sector_nr
) + sectors_skipped
;
2929 if (max_sector
> mddev
->resync_max
)
2930 max_sector
= mddev
->resync_max
; /* Don't do IO beyond here */
2932 /* make sure whole request will fit in a chunk - if chunks
2935 if (conf
->geo
.near_copies
< conf
->geo
.raid_disks
&&
2936 max_sector
> (sector_nr
| chunk_mask
))
2937 max_sector
= (sector_nr
| chunk_mask
) + 1;
2939 * If there is non-resync activity waiting for us then
2940 * put in a delay to throttle resync.
2942 if (!go_faster
&& conf
->nr_waiting
)
2943 msleep_interruptible(1000);
2945 /* Again, very different code for resync and recovery.
2946 * Both must result in an r10bio with a list of bios that
2947 * have bi_end_io, bi_sector, bi_bdev set,
2948 * and bi_private set to the r10bio.
2949 * For recovery, we may actually create several r10bios
2950 * with 2 bios in each, that correspond to the bios in the main one.
2951 * In this case, the subordinate r10bios link back through a
2952 * borrowed master_bio pointer, and the counter in the master
2953 * includes a ref from each subordinate.
2955 /* First, we decide what to do and set ->bi_end_io
2956 * To end_sync_read if we want to read, and
2957 * end_sync_write if we will want to write.
2960 max_sync
= RESYNC_PAGES
<< (PAGE_SHIFT
-9);
2961 if (!test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
)) {
2962 /* recovery... the complicated one */
2966 for (i
= 0 ; i
< conf
->geo
.raid_disks
; i
++) {
2972 struct raid10_info
*mirror
= &conf
->mirrors
[i
];
2974 if ((mirror
->rdev
== NULL
||
2975 test_bit(In_sync
, &mirror
->rdev
->flags
))
2977 (mirror
->replacement
== NULL
||
2979 &mirror
->replacement
->flags
)))
2983 /* want to reconstruct this device */
2985 sect
= raid10_find_virt(conf
, sector_nr
, i
);
2986 if (sect
>= mddev
->resync_max_sectors
) {
2987 /* last stripe is not complete - don't
2988 * try to recover this sector.
2992 /* Unless we are doing a full sync, or a replacement
2993 * we only need to recover the block if it is set in
2996 must_sync
= bitmap_start_sync(mddev
->bitmap
, sect
,
2998 if (sync_blocks
< max_sync
)
2999 max_sync
= sync_blocks
;
3001 mirror
->replacement
== NULL
&&
3003 /* yep, skip the sync_blocks here, but don't assume
3004 * that there will never be anything to do here
3006 chunks_skipped
= -1;
3010 r10_bio
= mempool_alloc(conf
->r10buf_pool
, GFP_NOIO
);
3011 raise_barrier(conf
, rb2
!= NULL
);
3012 atomic_set(&r10_bio
->remaining
, 0);
3014 r10_bio
->master_bio
= (struct bio
*)rb2
;
3016 atomic_inc(&rb2
->remaining
);
3017 r10_bio
->mddev
= mddev
;
3018 set_bit(R10BIO_IsRecover
, &r10_bio
->state
);
3019 r10_bio
->sector
= sect
;
3021 raid10_find_phys(conf
, r10_bio
);
3023 /* Need to check if the array will still be
3026 for (j
= 0; j
< conf
->geo
.raid_disks
; j
++)
3027 if (conf
->mirrors
[j
].rdev
== NULL
||
3028 test_bit(Faulty
, &conf
->mirrors
[j
].rdev
->flags
)) {
3033 must_sync
= bitmap_start_sync(mddev
->bitmap
, sect
,
3034 &sync_blocks
, still_degraded
);
3037 for (j
=0; j
<conf
->copies
;j
++) {
3039 int d
= r10_bio
->devs
[j
].devnum
;
3040 sector_t from_addr
, to_addr
;
3041 struct md_rdev
*rdev
;
3042 sector_t sector
, first_bad
;
3044 if (!conf
->mirrors
[d
].rdev
||
3045 !test_bit(In_sync
, &conf
->mirrors
[d
].rdev
->flags
))
3047 /* This is where we read from */
3049 rdev
= conf
->mirrors
[d
].rdev
;
3050 sector
= r10_bio
->devs
[j
].addr
;
3052 if (is_badblock(rdev
, sector
, max_sync
,
3053 &first_bad
, &bad_sectors
)) {
3054 if (first_bad
> sector
)
3055 max_sync
= first_bad
- sector
;
3057 bad_sectors
-= (sector
3059 if (max_sync
> bad_sectors
)
3060 max_sync
= bad_sectors
;
3064 bio
= r10_bio
->devs
[0].bio
;
3065 bio
->bi_next
= biolist
;
3067 bio
->bi_private
= r10_bio
;
3068 bio
->bi_end_io
= end_sync_read
;
3070 from_addr
= r10_bio
->devs
[j
].addr
;
3071 bio
->bi_sector
= from_addr
+ rdev
->data_offset
;
3072 bio
->bi_bdev
= rdev
->bdev
;
3073 atomic_inc(&rdev
->nr_pending
);
3074 /* and we write to 'i' (if not in_sync) */
3076 for (k
=0; k
<conf
->copies
; k
++)
3077 if (r10_bio
->devs
[k
].devnum
== i
)
3079 BUG_ON(k
== conf
->copies
);
3080 to_addr
= r10_bio
->devs
[k
].addr
;
3081 r10_bio
->devs
[0].devnum
= d
;
3082 r10_bio
->devs
[0].addr
= from_addr
;
3083 r10_bio
->devs
[1].devnum
= i
;
3084 r10_bio
->devs
[1].addr
= to_addr
;
3086 rdev
= mirror
->rdev
;
3087 if (!test_bit(In_sync
, &rdev
->flags
)) {
3088 bio
= r10_bio
->devs
[1].bio
;
3089 bio
->bi_next
= biolist
;
3091 bio
->bi_private
= r10_bio
;
3092 bio
->bi_end_io
= end_sync_write
;
3094 bio
->bi_sector
= to_addr
3095 + rdev
->data_offset
;
3096 bio
->bi_bdev
= rdev
->bdev
;
3097 atomic_inc(&r10_bio
->remaining
);
3099 r10_bio
->devs
[1].bio
->bi_end_io
= NULL
;
3101 /* and maybe write to replacement */
3102 bio
= r10_bio
->devs
[1].repl_bio
;
3104 bio
->bi_end_io
= NULL
;
3105 rdev
= mirror
->replacement
;
3106 /* Note: if rdev != NULL, then bio
3107 * cannot be NULL as r10buf_pool_alloc will
3108 * have allocated it.
3109 * So the second test here is pointless.
3110 * But it keeps semantic-checkers happy, and
3111 * this comment keeps human reviewers
3114 if (rdev
== NULL
|| bio
== NULL
||
3115 test_bit(Faulty
, &rdev
->flags
))
3117 bio
->bi_next
= biolist
;
3119 bio
->bi_private
= r10_bio
;
3120 bio
->bi_end_io
= end_sync_write
;
3122 bio
->bi_sector
= to_addr
+ rdev
->data_offset
;
3123 bio
->bi_bdev
= rdev
->bdev
;
3124 atomic_inc(&r10_bio
->remaining
);
3127 if (j
== conf
->copies
) {
3128 /* Cannot recover, so abort the recovery or
3129 * record a bad block */
3132 atomic_dec(&rb2
->remaining
);
3135 /* problem is that there are bad blocks
3136 * on other device(s)
3139 for (k
= 0; k
< conf
->copies
; k
++)
3140 if (r10_bio
->devs
[k
].devnum
== i
)
3142 if (!test_bit(In_sync
,
3143 &mirror
->rdev
->flags
)
3144 && !rdev_set_badblocks(
3146 r10_bio
->devs
[k
].addr
,
3149 if (mirror
->replacement
&&
3150 !rdev_set_badblocks(
3151 mirror
->replacement
,
3152 r10_bio
->devs
[k
].addr
,
3157 if (!test_and_set_bit(MD_RECOVERY_INTR
,
3159 printk(KERN_INFO
"md/raid10:%s: insufficient "
3160 "working devices for recovery.\n",
3162 mirror
->recovery_disabled
3163 = mddev
->recovery_disabled
;
3168 if (biolist
== NULL
) {
3170 struct r10bio
*rb2
= r10_bio
;
3171 r10_bio
= (struct r10bio
*) rb2
->master_bio
;
3172 rb2
->master_bio
= NULL
;
3178 /* resync. Schedule a read for every block at this virt offset */
3181 bitmap_cond_end_sync(mddev
->bitmap
, sector_nr
);
3183 if (!bitmap_start_sync(mddev
->bitmap
, sector_nr
,
3184 &sync_blocks
, mddev
->degraded
) &&
3185 !conf
->fullsync
&& !test_bit(MD_RECOVERY_REQUESTED
,
3186 &mddev
->recovery
)) {
3187 /* We can skip this block */
3189 return sync_blocks
+ sectors_skipped
;
3191 if (sync_blocks
< max_sync
)
3192 max_sync
= sync_blocks
;
3193 r10_bio
= mempool_alloc(conf
->r10buf_pool
, GFP_NOIO
);
3195 r10_bio
->mddev
= mddev
;
3196 atomic_set(&r10_bio
->remaining
, 0);
3197 raise_barrier(conf
, 0);
3198 conf
->next_resync
= sector_nr
;
3200 r10_bio
->master_bio
= NULL
;
3201 r10_bio
->sector
= sector_nr
;
3202 set_bit(R10BIO_IsSync
, &r10_bio
->state
);
3203 raid10_find_phys(conf
, r10_bio
);
3204 r10_bio
->sectors
= (sector_nr
| chunk_mask
) - sector_nr
+ 1;
3206 for (i
= 0; i
< conf
->copies
; i
++) {
3207 int d
= r10_bio
->devs
[i
].devnum
;
3208 sector_t first_bad
, sector
;
3211 if (r10_bio
->devs
[i
].repl_bio
)
3212 r10_bio
->devs
[i
].repl_bio
->bi_end_io
= NULL
;
3214 bio
= r10_bio
->devs
[i
].bio
;
3215 bio
->bi_end_io
= NULL
;
3216 clear_bit(BIO_UPTODATE
, &bio
->bi_flags
);
3217 if (conf
->mirrors
[d
].rdev
== NULL
||
3218 test_bit(Faulty
, &conf
->mirrors
[d
].rdev
->flags
))
3220 sector
= r10_bio
->devs
[i
].addr
;
3221 if (is_badblock(conf
->mirrors
[d
].rdev
,
3223 &first_bad
, &bad_sectors
)) {
3224 if (first_bad
> sector
)
3225 max_sync
= first_bad
- sector
;
3227 bad_sectors
-= (sector
- first_bad
);
3228 if (max_sync
> bad_sectors
)
3229 max_sync
= bad_sectors
;
3233 atomic_inc(&conf
->mirrors
[d
].rdev
->nr_pending
);
3234 atomic_inc(&r10_bio
->remaining
);
3235 bio
->bi_next
= biolist
;
3237 bio
->bi_private
= r10_bio
;
3238 bio
->bi_end_io
= end_sync_read
;
3240 bio
->bi_sector
= sector
+
3241 conf
->mirrors
[d
].rdev
->data_offset
;
3242 bio
->bi_bdev
= conf
->mirrors
[d
].rdev
->bdev
;
3245 if (conf
->mirrors
[d
].replacement
== NULL
||
3247 &conf
->mirrors
[d
].replacement
->flags
))
3250 /* Need to set up for writing to the replacement */
3251 bio
= r10_bio
->devs
[i
].repl_bio
;
3252 clear_bit(BIO_UPTODATE
, &bio
->bi_flags
);
3254 sector
= r10_bio
->devs
[i
].addr
;
3255 atomic_inc(&conf
->mirrors
[d
].rdev
->nr_pending
);
3256 bio
->bi_next
= biolist
;
3258 bio
->bi_private
= r10_bio
;
3259 bio
->bi_end_io
= end_sync_write
;
3261 bio
->bi_sector
= sector
+
3262 conf
->mirrors
[d
].replacement
->data_offset
;
3263 bio
->bi_bdev
= conf
->mirrors
[d
].replacement
->bdev
;
3268 for (i
=0; i
<conf
->copies
; i
++) {
3269 int d
= r10_bio
->devs
[i
].devnum
;
3270 if (r10_bio
->devs
[i
].bio
->bi_end_io
)
3271 rdev_dec_pending(conf
->mirrors
[d
].rdev
,
3273 if (r10_bio
->devs
[i
].repl_bio
&&
3274 r10_bio
->devs
[i
].repl_bio
->bi_end_io
)
3276 conf
->mirrors
[d
].replacement
,
3285 for (bio
= biolist
; bio
; bio
=bio
->bi_next
) {
3287 bio
->bi_flags
&= ~(BIO_POOL_MASK
- 1);
3289 bio
->bi_flags
|= 1 << BIO_UPTODATE
;
3292 bio
->bi_phys_segments
= 0;
3297 if (sector_nr
+ max_sync
< max_sector
)
3298 max_sector
= sector_nr
+ max_sync
;
3301 int len
= PAGE_SIZE
;
3302 if (sector_nr
+ (len
>>9) > max_sector
)
3303 len
= (max_sector
- sector_nr
) << 9;
3306 for (bio
= biolist
; bio
; bio
=bio
->bi_next
) {
3308 page
= bio
->bi_io_vec
[bio
->bi_vcnt
].bv_page
;
3309 if (bio_add_page(bio
, page
, len
, 0))
3313 bio
->bi_io_vec
[bio
->bi_vcnt
].bv_page
= page
;
3314 for (bio2
= biolist
;
3315 bio2
&& bio2
!= bio
;
3316 bio2
= bio2
->bi_next
) {
3317 /* remove last page from this bio */
3319 bio2
->bi_size
-= len
;
3320 bio2
->bi_flags
&= ~(1<< BIO_SEG_VALID
);
3324 nr_sectors
+= len
>>9;
3325 sector_nr
+= len
>>9;
3326 } while (biolist
->bi_vcnt
< RESYNC_PAGES
);
3328 r10_bio
->sectors
= nr_sectors
;
3332 biolist
= biolist
->bi_next
;
3334 bio
->bi_next
= NULL
;
3335 r10_bio
= bio
->bi_private
;
3336 r10_bio
->sectors
= nr_sectors
;
3338 if (bio
->bi_end_io
== end_sync_read
) {
3339 md_sync_acct(bio
->bi_bdev
, nr_sectors
);
3340 generic_make_request(bio
);
3344 if (sectors_skipped
)
3345 /* pretend they weren't skipped, it makes
3346 * no important difference in this case
3348 md_done_sync(mddev
, sectors_skipped
, 1);
3350 return sectors_skipped
+ nr_sectors
;
3352 /* There is nowhere to write, so all non-sync
3353 * drives must be failed or in resync, all drives
3354 * have a bad block, so try the next chunk...
3356 if (sector_nr
+ max_sync
< max_sector
)
3357 max_sector
= sector_nr
+ max_sync
;
3359 sectors_skipped
+= (max_sector
- sector_nr
);
3361 sector_nr
= max_sector
;
3366 raid10_size(struct mddev
*mddev
, sector_t sectors
, int raid_disks
)
3369 struct r10conf
*conf
= mddev
->private;
3372 raid_disks
= min(conf
->geo
.raid_disks
,
3373 conf
->prev
.raid_disks
);
3375 sectors
= conf
->dev_sectors
;
3377 size
= sectors
>> conf
->geo
.chunk_shift
;
3378 sector_div(size
, conf
->geo
.far_copies
);
3379 size
= size
* raid_disks
;
3380 sector_div(size
, conf
->geo
.near_copies
);
3382 return size
<< conf
->geo
.chunk_shift
;
3385 static void calc_sectors(struct r10conf
*conf
, sector_t size
)
3387 /* Calculate the number of sectors-per-device that will
3388 * actually be used, and set conf->dev_sectors and
3392 size
= size
>> conf
->geo
.chunk_shift
;
3393 sector_div(size
, conf
->geo
.far_copies
);
3394 size
= size
* conf
->geo
.raid_disks
;
3395 sector_div(size
, conf
->geo
.near_copies
);
3396 /* 'size' is now the number of chunks in the array */
3397 /* calculate "used chunks per device" */
3398 size
= size
* conf
->copies
;
3400 /* We need to round up when dividing by raid_disks to
3401 * get the stride size.
3403 size
= DIV_ROUND_UP_SECTOR_T(size
, conf
->geo
.raid_disks
);
3405 conf
->dev_sectors
= size
<< conf
->geo
.chunk_shift
;
3407 if (conf
->geo
.far_offset
)
3408 conf
->geo
.stride
= 1 << conf
->geo
.chunk_shift
;
3410 sector_div(size
, conf
->geo
.far_copies
);
3411 conf
->geo
.stride
= size
<< conf
->geo
.chunk_shift
;
3415 enum geo_type
{geo_new
, geo_old
, geo_start
};
3416 static int setup_geo(struct geom
*geo
, struct mddev
*mddev
, enum geo_type
new)
3419 int layout
, chunk
, disks
;
3422 layout
= mddev
->layout
;
3423 chunk
= mddev
->chunk_sectors
;
3424 disks
= mddev
->raid_disks
- mddev
->delta_disks
;
3427 layout
= mddev
->new_layout
;
3428 chunk
= mddev
->new_chunk_sectors
;
3429 disks
= mddev
->raid_disks
;
3431 default: /* avoid 'may be unused' warnings */
3432 case geo_start
: /* new when starting reshape - raid_disks not
3434 layout
= mddev
->new_layout
;
3435 chunk
= mddev
->new_chunk_sectors
;
3436 disks
= mddev
->raid_disks
+ mddev
->delta_disks
;
3441 if (chunk
< (PAGE_SIZE
>> 9) ||
3442 !is_power_of_2(chunk
))
3445 fc
= (layout
>> 8) & 255;
3446 fo
= layout
& (1<<16);
3447 geo
->raid_disks
= disks
;
3448 geo
->near_copies
= nc
;
3449 geo
->far_copies
= fc
;
3450 geo
->far_offset
= fo
;
3451 geo
->chunk_mask
= chunk
- 1;
3452 geo
->chunk_shift
= ffz(~chunk
);
3456 static struct r10conf
*setup_conf(struct mddev
*mddev
)
3458 struct r10conf
*conf
= NULL
;
3463 copies
= setup_geo(&geo
, mddev
, geo_new
);
3466 printk(KERN_ERR
"md/raid10:%s: chunk size must be "
3467 "at least PAGE_SIZE(%ld) and be a power of 2.\n",
3468 mdname(mddev
), PAGE_SIZE
);
3472 if (copies
< 2 || copies
> mddev
->raid_disks
) {
3473 printk(KERN_ERR
"md/raid10:%s: unsupported raid10 layout: 0x%8x\n",
3474 mdname(mddev
), mddev
->new_layout
);
3479 conf
= kzalloc(sizeof(struct r10conf
), GFP_KERNEL
);
3483 /* FIXME calc properly */
3484 conf
->mirrors
= kzalloc(sizeof(struct raid10_info
)*(mddev
->raid_disks
+
3485 max(0,mddev
->delta_disks
)),
3490 conf
->tmppage
= alloc_page(GFP_KERNEL
);
3495 conf
->copies
= copies
;
3496 conf
->r10bio_pool
= mempool_create(NR_RAID10_BIOS
, r10bio_pool_alloc
,
3497 r10bio_pool_free
, conf
);
3498 if (!conf
->r10bio_pool
)
3501 calc_sectors(conf
, mddev
->dev_sectors
);
3502 if (mddev
->reshape_position
== MaxSector
) {
3503 conf
->prev
= conf
->geo
;
3504 conf
->reshape_progress
= MaxSector
;
3506 if (setup_geo(&conf
->prev
, mddev
, geo_old
) != conf
->copies
) {
3510 conf
->reshape_progress
= mddev
->reshape_position
;
3511 if (conf
->prev
.far_offset
)
3512 conf
->prev
.stride
= 1 << conf
->prev
.chunk_shift
;
3514 /* far_copies must be 1 */
3515 conf
->prev
.stride
= conf
->dev_sectors
;
3517 spin_lock_init(&conf
->device_lock
);
3518 INIT_LIST_HEAD(&conf
->retry_list
);
3520 spin_lock_init(&conf
->resync_lock
);
3521 init_waitqueue_head(&conf
->wait_barrier
);
3523 conf
->thread
= md_register_thread(raid10d
, mddev
, "raid10");
3527 conf
->mddev
= mddev
;
3532 printk(KERN_ERR
"md/raid10:%s: couldn't allocate memory.\n",
3535 if (conf
->r10bio_pool
)
3536 mempool_destroy(conf
->r10bio_pool
);
3537 kfree(conf
->mirrors
);
3538 safe_put_page(conf
->tmppage
);
3541 return ERR_PTR(err
);
3544 static int run(struct mddev
*mddev
)
3546 struct r10conf
*conf
;
3547 int i
, disk_idx
, chunk_size
;
3548 struct raid10_info
*disk
;
3549 struct md_rdev
*rdev
;
3551 sector_t min_offset_diff
= 0;
3553 bool discard_supported
= false;
3555 if (mddev
->private == NULL
) {
3556 conf
= setup_conf(mddev
);
3558 return PTR_ERR(conf
);
3559 mddev
->private = conf
;
3561 conf
= mddev
->private;
3565 mddev
->thread
= conf
->thread
;
3566 conf
->thread
= NULL
;
3568 chunk_size
= mddev
->chunk_sectors
<< 9;
3570 blk_queue_max_discard_sectors(mddev
->queue
,
3571 mddev
->chunk_sectors
);
3572 blk_queue_io_min(mddev
->queue
, chunk_size
);
3573 if (conf
->geo
.raid_disks
% conf
->geo
.near_copies
)
3574 blk_queue_io_opt(mddev
->queue
, chunk_size
* conf
->geo
.raid_disks
);
3576 blk_queue_io_opt(mddev
->queue
, chunk_size
*
3577 (conf
->geo
.raid_disks
/ conf
->geo
.near_copies
));
3580 rdev_for_each(rdev
, mddev
) {
3582 struct request_queue
*q
;
3584 disk_idx
= rdev
->raid_disk
;
3587 if (disk_idx
>= conf
->geo
.raid_disks
&&
3588 disk_idx
>= conf
->prev
.raid_disks
)
3590 disk
= conf
->mirrors
+ disk_idx
;
3592 if (test_bit(Replacement
, &rdev
->flags
)) {
3593 if (disk
->replacement
)
3595 disk
->replacement
= rdev
;
3601 q
= bdev_get_queue(rdev
->bdev
);
3602 if (q
->merge_bvec_fn
)
3603 mddev
->merge_check_needed
= 1;
3604 diff
= (rdev
->new_data_offset
- rdev
->data_offset
);
3605 if (!mddev
->reshape_backwards
)
3609 if (first
|| diff
< min_offset_diff
)
3610 min_offset_diff
= diff
;
3613 disk_stack_limits(mddev
->gendisk
, rdev
->bdev
,
3614 rdev
->data_offset
<< 9);
3616 disk
->head_position
= 0;
3618 if (blk_queue_discard(bdev_get_queue(rdev
->bdev
)))
3619 discard_supported
= true;
3623 if (discard_supported
)
3624 queue_flag_set_unlocked(QUEUE_FLAG_DISCARD
,
3627 queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD
,
3630 /* need to check that every block has at least one working mirror */
3631 if (!enough(conf
, -1)) {
3632 printk(KERN_ERR
"md/raid10:%s: not enough operational mirrors.\n",
3637 if (conf
->reshape_progress
!= MaxSector
) {
3638 /* must ensure that shape change is supported */
3639 if (conf
->geo
.far_copies
!= 1 &&
3640 conf
->geo
.far_offset
== 0)
3642 if (conf
->prev
.far_copies
!= 1 &&
3643 conf
->geo
.far_offset
== 0)
3647 mddev
->degraded
= 0;
3649 i
< conf
->geo
.raid_disks
3650 || i
< conf
->prev
.raid_disks
;
3653 disk
= conf
->mirrors
+ i
;
3655 if (!disk
->rdev
&& disk
->replacement
) {
3656 /* The replacement is all we have - use it */
3657 disk
->rdev
= disk
->replacement
;
3658 disk
->replacement
= NULL
;
3659 clear_bit(Replacement
, &disk
->rdev
->flags
);
3663 !test_bit(In_sync
, &disk
->rdev
->flags
)) {
3664 disk
->head_position
= 0;
3669 disk
->recovery_disabled
= mddev
->recovery_disabled
- 1;
3672 if (mddev
->recovery_cp
!= MaxSector
)
3673 printk(KERN_NOTICE
"md/raid10:%s: not clean"
3674 " -- starting background reconstruction\n",
3677 "md/raid10:%s: active with %d out of %d devices\n",
3678 mdname(mddev
), conf
->geo
.raid_disks
- mddev
->degraded
,
3679 conf
->geo
.raid_disks
);
3681 * Ok, everything is just fine now
3683 mddev
->dev_sectors
= conf
->dev_sectors
;
3684 size
= raid10_size(mddev
, 0, 0);
3685 md_set_array_sectors(mddev
, size
);
3686 mddev
->resync_max_sectors
= size
;
3689 int stripe
= conf
->geo
.raid_disks
*
3690 ((mddev
->chunk_sectors
<< 9) / PAGE_SIZE
);
3691 mddev
->queue
->backing_dev_info
.congested_fn
= raid10_congested
;
3692 mddev
->queue
->backing_dev_info
.congested_data
= mddev
;
3694 /* Calculate max read-ahead size.
3695 * We need to readahead at least twice a whole stripe....
3698 stripe
/= conf
->geo
.near_copies
;
3699 if (mddev
->queue
->backing_dev_info
.ra_pages
< 2 * stripe
)
3700 mddev
->queue
->backing_dev_info
.ra_pages
= 2 * stripe
;
3701 blk_queue_merge_bvec(mddev
->queue
, raid10_mergeable_bvec
);
3705 if (md_integrity_register(mddev
))
3708 if (conf
->reshape_progress
!= MaxSector
) {
3709 unsigned long before_length
, after_length
;
3711 before_length
= ((1 << conf
->prev
.chunk_shift
) *
3712 conf
->prev
.far_copies
);
3713 after_length
= ((1 << conf
->geo
.chunk_shift
) *
3714 conf
->geo
.far_copies
);
3716 if (max(before_length
, after_length
) > min_offset_diff
) {
3717 /* This cannot work */
3718 printk("md/raid10: offset difference not enough to continue reshape\n");
3721 conf
->offset_diff
= min_offset_diff
;
3723 conf
->reshape_safe
= conf
->reshape_progress
;
3724 clear_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
);
3725 clear_bit(MD_RECOVERY_CHECK
, &mddev
->recovery
);
3726 set_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
);
3727 set_bit(MD_RECOVERY_RUNNING
, &mddev
->recovery
);
3728 mddev
->sync_thread
= md_register_thread(md_do_sync
, mddev
,
3735 md_unregister_thread(&mddev
->thread
);
3736 if (conf
->r10bio_pool
)
3737 mempool_destroy(conf
->r10bio_pool
);
3738 safe_put_page(conf
->tmppage
);
3739 kfree(conf
->mirrors
);
3741 mddev
->private = NULL
;
3746 static int stop(struct mddev
*mddev
)
3748 struct r10conf
*conf
= mddev
->private;
3750 raise_barrier(conf
, 0);
3751 lower_barrier(conf
);
3753 md_unregister_thread(&mddev
->thread
);
3755 /* the unplug fn references 'conf'*/
3756 blk_sync_queue(mddev
->queue
);
3758 if (conf
->r10bio_pool
)
3759 mempool_destroy(conf
->r10bio_pool
);
3760 kfree(conf
->mirrors
);
3762 mddev
->private = NULL
;
3766 static void raid10_quiesce(struct mddev
*mddev
, int state
)
3768 struct r10conf
*conf
= mddev
->private;
3772 raise_barrier(conf
, 0);
3775 lower_barrier(conf
);
3780 static int raid10_resize(struct mddev
*mddev
, sector_t sectors
)
3782 /* Resize of 'far' arrays is not supported.
3783 * For 'near' and 'offset' arrays we can set the
3784 * number of sectors used to be an appropriate multiple
3785 * of the chunk size.
3786 * For 'offset', this is far_copies*chunksize.
3787 * For 'near' the multiplier is the LCM of
3788 * near_copies and raid_disks.
3789 * So if far_copies > 1 && !far_offset, fail.
3790 * Else find LCM(raid_disks, near_copy)*far_copies and
3791 * multiply by chunk_size. Then round to this number.
3792 * This is mostly done by raid10_size()
3794 struct r10conf
*conf
= mddev
->private;
3795 sector_t oldsize
, size
;
3797 if (mddev
->reshape_position
!= MaxSector
)
3800 if (conf
->geo
.far_copies
> 1 && !conf
->geo
.far_offset
)
3803 oldsize
= raid10_size(mddev
, 0, 0);
3804 size
= raid10_size(mddev
, sectors
, 0);
3805 if (mddev
->external_size
&&
3806 mddev
->array_sectors
> size
)
3808 if (mddev
->bitmap
) {
3809 int ret
= bitmap_resize(mddev
->bitmap
, size
, 0, 0);
3813 md_set_array_sectors(mddev
, size
);
3814 set_capacity(mddev
->gendisk
, mddev
->array_sectors
);
3815 revalidate_disk(mddev
->gendisk
);
3816 if (sectors
> mddev
->dev_sectors
&&
3817 mddev
->recovery_cp
> oldsize
) {
3818 mddev
->recovery_cp
= oldsize
;
3819 set_bit(MD_RECOVERY_NEEDED
, &mddev
->recovery
);
3821 calc_sectors(conf
, sectors
);
3822 mddev
->dev_sectors
= conf
->dev_sectors
;
3823 mddev
->resync_max_sectors
= size
;
3827 static void *raid10_takeover_raid0(struct mddev
*mddev
)
3829 struct md_rdev
*rdev
;
3830 struct r10conf
*conf
;
3832 if (mddev
->degraded
> 0) {
3833 printk(KERN_ERR
"md/raid10:%s: Error: degraded raid0!\n",
3835 return ERR_PTR(-EINVAL
);
3838 /* Set new parameters */
3839 mddev
->new_level
= 10;
3840 /* new layout: far_copies = 1, near_copies = 2 */
3841 mddev
->new_layout
= (1<<8) + 2;
3842 mddev
->new_chunk_sectors
= mddev
->chunk_sectors
;
3843 mddev
->delta_disks
= mddev
->raid_disks
;
3844 mddev
->raid_disks
*= 2;
3845 /* make sure it will be not marked as dirty */
3846 mddev
->recovery_cp
= MaxSector
;
3848 conf
= setup_conf(mddev
);
3849 if (!IS_ERR(conf
)) {
3850 rdev_for_each(rdev
, mddev
)
3851 if (rdev
->raid_disk
>= 0)
3852 rdev
->new_raid_disk
= rdev
->raid_disk
* 2;
3859 static void *raid10_takeover(struct mddev
*mddev
)
3861 struct r0conf
*raid0_conf
;
3863 /* raid10 can take over:
3864 * raid0 - providing it has only two drives
3866 if (mddev
->level
== 0) {
3867 /* for raid0 takeover only one zone is supported */
3868 raid0_conf
= mddev
->private;
3869 if (raid0_conf
->nr_strip_zones
> 1) {
3870 printk(KERN_ERR
"md/raid10:%s: cannot takeover raid 0"
3871 " with more than one zone.\n",
3873 return ERR_PTR(-EINVAL
);
3875 return raid10_takeover_raid0(mddev
);
3877 return ERR_PTR(-EINVAL
);
3880 static int raid10_check_reshape(struct mddev
*mddev
)
3882 /* Called when there is a request to change
3883 * - layout (to ->new_layout)
3884 * - chunk size (to ->new_chunk_sectors)
3885 * - raid_disks (by delta_disks)
3886 * or when trying to restart a reshape that was ongoing.
3888 * We need to validate the request and possibly allocate
3889 * space if that might be an issue later.
3891 * Currently we reject any reshape of a 'far' mode array,
3892 * allow chunk size to change if new is generally acceptable,
3893 * allow raid_disks to increase, and allow
3894 * a switch between 'near' mode and 'offset' mode.
3896 struct r10conf
*conf
= mddev
->private;
3899 if (conf
->geo
.far_copies
!= 1 && !conf
->geo
.far_offset
)
3902 if (setup_geo(&geo
, mddev
, geo_start
) != conf
->copies
)
3903 /* mustn't change number of copies */
3905 if (geo
.far_copies
> 1 && !geo
.far_offset
)
3906 /* Cannot switch to 'far' mode */
3909 if (mddev
->array_sectors
& geo
.chunk_mask
)
3910 /* not factor of array size */
3913 if (!enough(conf
, -1))
3916 kfree(conf
->mirrors_new
);
3917 conf
->mirrors_new
= NULL
;
3918 if (mddev
->delta_disks
> 0) {
3919 /* allocate new 'mirrors' list */
3920 conf
->mirrors_new
= kzalloc(
3921 sizeof(struct raid10_info
)
3922 *(mddev
->raid_disks
+
3923 mddev
->delta_disks
),
3925 if (!conf
->mirrors_new
)
3932 * Need to check if array has failed when deciding whether to:
3934 * - remove non-faulty devices
3937 * This determination is simple when no reshape is happening.
3938 * However if there is a reshape, we need to carefully check
3939 * both the before and after sections.
3940 * This is because some failed devices may only affect one
3941 * of the two sections, and some non-in_sync devices may
3942 * be insync in the section most affected by failed devices.
3944 static int calc_degraded(struct r10conf
*conf
)
3946 int degraded
, degraded2
;
3951 /* 'prev' section first */
3952 for (i
= 0; i
< conf
->prev
.raid_disks
; i
++) {
3953 struct md_rdev
*rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
3954 if (!rdev
|| test_bit(Faulty
, &rdev
->flags
))
3956 else if (!test_bit(In_sync
, &rdev
->flags
))
3957 /* When we can reduce the number of devices in
3958 * an array, this might not contribute to
3959 * 'degraded'. It does now.
3964 if (conf
->geo
.raid_disks
== conf
->prev
.raid_disks
)
3968 for (i
= 0; i
< conf
->geo
.raid_disks
; i
++) {
3969 struct md_rdev
*rdev
= rcu_dereference(conf
->mirrors
[i
].rdev
);
3970 if (!rdev
|| test_bit(Faulty
, &rdev
->flags
))
3972 else if (!test_bit(In_sync
, &rdev
->flags
)) {
3973 /* If reshape is increasing the number of devices,
3974 * this section has already been recovered, so
3975 * it doesn't contribute to degraded.
3978 if (conf
->geo
.raid_disks
<= conf
->prev
.raid_disks
)
3983 if (degraded2
> degraded
)
3988 static int raid10_start_reshape(struct mddev
*mddev
)
3990 /* A 'reshape' has been requested. This commits
3991 * the various 'new' fields and sets MD_RECOVER_RESHAPE
3992 * This also checks if there are enough spares and adds them
3994 * We currently require enough spares to make the final
3995 * array non-degraded. We also require that the difference
3996 * between old and new data_offset - on each device - is
3997 * enough that we never risk over-writing.
4000 unsigned long before_length
, after_length
;
4001 sector_t min_offset_diff
= 0;
4004 struct r10conf
*conf
= mddev
->private;
4005 struct md_rdev
*rdev
;
4009 if (test_bit(MD_RECOVERY_RUNNING
, &mddev
->recovery
))
4012 if (setup_geo(&new, mddev
, geo_start
) != conf
->copies
)
4015 before_length
= ((1 << conf
->prev
.chunk_shift
) *
4016 conf
->prev
.far_copies
);
4017 after_length
= ((1 << conf
->geo
.chunk_shift
) *
4018 conf
->geo
.far_copies
);
4020 rdev_for_each(rdev
, mddev
) {
4021 if (!test_bit(In_sync
, &rdev
->flags
)
4022 && !test_bit(Faulty
, &rdev
->flags
))
4024 if (rdev
->raid_disk
>= 0) {
4025 long long diff
= (rdev
->new_data_offset
4026 - rdev
->data_offset
);
4027 if (!mddev
->reshape_backwards
)
4031 if (first
|| diff
< min_offset_diff
)
4032 min_offset_diff
= diff
;
4036 if (max(before_length
, after_length
) > min_offset_diff
)
4039 if (spares
< mddev
->delta_disks
)
4042 conf
->offset_diff
= min_offset_diff
;
4043 spin_lock_irq(&conf
->device_lock
);
4044 if (conf
->mirrors_new
) {
4045 memcpy(conf
->mirrors_new
, conf
->mirrors
,
4046 sizeof(struct raid10_info
)*conf
->prev
.raid_disks
);
4048 kfree(conf
->mirrors_old
); /* FIXME and elsewhere */
4049 conf
->mirrors_old
= conf
->mirrors
;
4050 conf
->mirrors
= conf
->mirrors_new
;
4051 conf
->mirrors_new
= NULL
;
4053 setup_geo(&conf
->geo
, mddev
, geo_start
);
4055 if (mddev
->reshape_backwards
) {
4056 sector_t size
= raid10_size(mddev
, 0, 0);
4057 if (size
< mddev
->array_sectors
) {
4058 spin_unlock_irq(&conf
->device_lock
);
4059 printk(KERN_ERR
"md/raid10:%s: array size must be reduce before number of disks\n",
4063 mddev
->resync_max_sectors
= size
;
4064 conf
->reshape_progress
= size
;
4066 conf
->reshape_progress
= 0;
4067 spin_unlock_irq(&conf
->device_lock
);
4069 if (mddev
->delta_disks
&& mddev
->bitmap
) {
4070 ret
= bitmap_resize(mddev
->bitmap
,
4071 raid10_size(mddev
, 0,
4072 conf
->geo
.raid_disks
),
4077 if (mddev
->delta_disks
> 0) {
4078 rdev_for_each(rdev
, mddev
)
4079 if (rdev
->raid_disk
< 0 &&
4080 !test_bit(Faulty
, &rdev
->flags
)) {
4081 if (raid10_add_disk(mddev
, rdev
) == 0) {
4082 if (rdev
->raid_disk
>=
4083 conf
->prev
.raid_disks
)
4084 set_bit(In_sync
, &rdev
->flags
);
4086 rdev
->recovery_offset
= 0;
4088 if (sysfs_link_rdev(mddev
, rdev
))
4089 /* Failure here is OK */;
4091 } else if (rdev
->raid_disk
>= conf
->prev
.raid_disks
4092 && !test_bit(Faulty
, &rdev
->flags
)) {
4093 /* This is a spare that was manually added */
4094 set_bit(In_sync
, &rdev
->flags
);
4097 /* When a reshape changes the number of devices,
4098 * ->degraded is measured against the larger of the
4099 * pre and post numbers.
4101 spin_lock_irq(&conf
->device_lock
);
4102 mddev
->degraded
= calc_degraded(conf
);
4103 spin_unlock_irq(&conf
->device_lock
);
4104 mddev
->raid_disks
= conf
->geo
.raid_disks
;
4105 mddev
->reshape_position
= conf
->reshape_progress
;
4106 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
4108 clear_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
);
4109 clear_bit(MD_RECOVERY_CHECK
, &mddev
->recovery
);
4110 set_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
);
4111 set_bit(MD_RECOVERY_RUNNING
, &mddev
->recovery
);
4113 mddev
->sync_thread
= md_register_thread(md_do_sync
, mddev
,
4115 if (!mddev
->sync_thread
) {
4119 conf
->reshape_checkpoint
= jiffies
;
4120 md_wakeup_thread(mddev
->sync_thread
);
4121 md_new_event(mddev
);
4125 mddev
->recovery
= 0;
4126 spin_lock_irq(&conf
->device_lock
);
4127 conf
->geo
= conf
->prev
;
4128 mddev
->raid_disks
= conf
->geo
.raid_disks
;
4129 rdev_for_each(rdev
, mddev
)
4130 rdev
->new_data_offset
= rdev
->data_offset
;
4132 conf
->reshape_progress
= MaxSector
;
4133 mddev
->reshape_position
= MaxSector
;
4134 spin_unlock_irq(&conf
->device_lock
);
4138 /* Calculate the last device-address that could contain
4139 * any block from the chunk that includes the array-address 's'
4140 * and report the next address.
4141 * i.e. the address returned will be chunk-aligned and after
4142 * any data that is in the chunk containing 's'.
4144 static sector_t
last_dev_address(sector_t s
, struct geom
*geo
)
4146 s
= (s
| geo
->chunk_mask
) + 1;
4147 s
>>= geo
->chunk_shift
;
4148 s
*= geo
->near_copies
;
4149 s
= DIV_ROUND_UP_SECTOR_T(s
, geo
->raid_disks
);
4150 s
*= geo
->far_copies
;
4151 s
<<= geo
->chunk_shift
;
4155 /* Calculate the first device-address that could contain
4156 * any block from the chunk that includes the array-address 's'.
4157 * This too will be the start of a chunk
4159 static sector_t
first_dev_address(sector_t s
, struct geom
*geo
)
4161 s
>>= geo
->chunk_shift
;
4162 s
*= geo
->near_copies
;
4163 sector_div(s
, geo
->raid_disks
);
4164 s
*= geo
->far_copies
;
4165 s
<<= geo
->chunk_shift
;
4169 static sector_t
reshape_request(struct mddev
*mddev
, sector_t sector_nr
,
4172 /* We simply copy at most one chunk (smallest of old and new)
4173 * at a time, possibly less if that exceeds RESYNC_PAGES,
4174 * or we hit a bad block or something.
4175 * This might mean we pause for normal IO in the middle of
4176 * a chunk, but that is not a problem was mddev->reshape_position
4177 * can record any location.
4179 * If we will want to write to a location that isn't
4180 * yet recorded as 'safe' (i.e. in metadata on disk) then
4181 * we need to flush all reshape requests and update the metadata.
4183 * When reshaping forwards (e.g. to more devices), we interpret
4184 * 'safe' as the earliest block which might not have been copied
4185 * down yet. We divide this by previous stripe size and multiply
4186 * by previous stripe length to get lowest device offset that we
4187 * cannot write to yet.
4188 * We interpret 'sector_nr' as an address that we want to write to.
4189 * From this we use last_device_address() to find where we might
4190 * write to, and first_device_address on the 'safe' position.
4191 * If this 'next' write position is after the 'safe' position,
4192 * we must update the metadata to increase the 'safe' position.
4194 * When reshaping backwards, we round in the opposite direction
4195 * and perform the reverse test: next write position must not be
4196 * less than current safe position.
4198 * In all this the minimum difference in data offsets
4199 * (conf->offset_diff - always positive) allows a bit of slack,
4200 * so next can be after 'safe', but not by more than offset_disk
4202 * We need to prepare all the bios here before we start any IO
4203 * to ensure the size we choose is acceptable to all devices.
4204 * The means one for each copy for write-out and an extra one for
4206 * We store the read-in bio in ->master_bio and the others in
4207 * ->devs[x].bio and ->devs[x].repl_bio.
4209 struct r10conf
*conf
= mddev
->private;
4210 struct r10bio
*r10_bio
;
4211 sector_t next
, safe
, last
;
4215 struct md_rdev
*rdev
;
4218 struct bio
*bio
, *read_bio
;
4219 int sectors_done
= 0;
4221 if (sector_nr
== 0) {
4222 /* If restarting in the middle, skip the initial sectors */
4223 if (mddev
->reshape_backwards
&&
4224 conf
->reshape_progress
< raid10_size(mddev
, 0, 0)) {
4225 sector_nr
= (raid10_size(mddev
, 0, 0)
4226 - conf
->reshape_progress
);
4227 } else if (!mddev
->reshape_backwards
&&
4228 conf
->reshape_progress
> 0)
4229 sector_nr
= conf
->reshape_progress
;
4231 mddev
->curr_resync_completed
= sector_nr
;
4232 sysfs_notify(&mddev
->kobj
, NULL
, "sync_completed");
4238 /* We don't use sector_nr to track where we are up to
4239 * as that doesn't work well for ->reshape_backwards.
4240 * So just use ->reshape_progress.
4242 if (mddev
->reshape_backwards
) {
4243 /* 'next' is the earliest device address that we might
4244 * write to for this chunk in the new layout
4246 next
= first_dev_address(conf
->reshape_progress
- 1,
4249 /* 'safe' is the last device address that we might read from
4250 * in the old layout after a restart
4252 safe
= last_dev_address(conf
->reshape_safe
- 1,
4255 if (next
+ conf
->offset_diff
< safe
)
4258 last
= conf
->reshape_progress
- 1;
4259 sector_nr
= last
& ~(sector_t
)(conf
->geo
.chunk_mask
4260 & conf
->prev
.chunk_mask
);
4261 if (sector_nr
+ RESYNC_BLOCK_SIZE
/512 < last
)
4262 sector_nr
= last
+ 1 - RESYNC_BLOCK_SIZE
/512;
4264 /* 'next' is after the last device address that we
4265 * might write to for this chunk in the new layout
4267 next
= last_dev_address(conf
->reshape_progress
, &conf
->geo
);
4269 /* 'safe' is the earliest device address that we might
4270 * read from in the old layout after a restart
4272 safe
= first_dev_address(conf
->reshape_safe
, &conf
->prev
);
4274 /* Need to update metadata if 'next' might be beyond 'safe'
4275 * as that would possibly corrupt data
4277 if (next
> safe
+ conf
->offset_diff
)
4280 sector_nr
= conf
->reshape_progress
;
4281 last
= sector_nr
| (conf
->geo
.chunk_mask
4282 & conf
->prev
.chunk_mask
);
4284 if (sector_nr
+ RESYNC_BLOCK_SIZE
/512 <= last
)
4285 last
= sector_nr
+ RESYNC_BLOCK_SIZE
/512 - 1;
4289 time_after(jiffies
, conf
->reshape_checkpoint
+ 10*HZ
)) {
4290 /* Need to update reshape_position in metadata */
4292 mddev
->reshape_position
= conf
->reshape_progress
;
4293 if (mddev
->reshape_backwards
)
4294 mddev
->curr_resync_completed
= raid10_size(mddev
, 0, 0)
4295 - conf
->reshape_progress
;
4297 mddev
->curr_resync_completed
= conf
->reshape_progress
;
4298 conf
->reshape_checkpoint
= jiffies
;
4299 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
4300 md_wakeup_thread(mddev
->thread
);
4301 wait_event(mddev
->sb_wait
, mddev
->flags
== 0 ||
4302 kthread_should_stop());
4303 conf
->reshape_safe
= mddev
->reshape_position
;
4304 allow_barrier(conf
);
4308 /* Now schedule reads for blocks from sector_nr to last */
4309 r10_bio
= mempool_alloc(conf
->r10buf_pool
, GFP_NOIO
);
4310 raise_barrier(conf
, sectors_done
!= 0);
4311 atomic_set(&r10_bio
->remaining
, 0);
4312 r10_bio
->mddev
= mddev
;
4313 r10_bio
->sector
= sector_nr
;
4314 set_bit(R10BIO_IsReshape
, &r10_bio
->state
);
4315 r10_bio
->sectors
= last
- sector_nr
+ 1;
4316 rdev
= read_balance(conf
, r10_bio
, &max_sectors
);
4317 BUG_ON(!test_bit(R10BIO_Previous
, &r10_bio
->state
));
4320 /* Cannot read from here, so need to record bad blocks
4321 * on all the target devices.
4324 set_bit(MD_RECOVERY_INTR
, &mddev
->recovery
);
4325 return sectors_done
;
4328 read_bio
= bio_alloc_mddev(GFP_KERNEL
, RESYNC_PAGES
, mddev
);
4330 read_bio
->bi_bdev
= rdev
->bdev
;
4331 read_bio
->bi_sector
= (r10_bio
->devs
[r10_bio
->read_slot
].addr
4332 + rdev
->data_offset
);
4333 read_bio
->bi_private
= r10_bio
;
4334 read_bio
->bi_end_io
= end_sync_read
;
4335 read_bio
->bi_rw
= READ
;
4336 read_bio
->bi_flags
&= ~(BIO_POOL_MASK
- 1);
4337 read_bio
->bi_flags
|= 1 << BIO_UPTODATE
;
4338 read_bio
->bi_vcnt
= 0;
4339 read_bio
->bi_idx
= 0;
4340 read_bio
->bi_size
= 0;
4341 r10_bio
->master_bio
= read_bio
;
4342 r10_bio
->read_slot
= r10_bio
->devs
[r10_bio
->read_slot
].devnum
;
4344 /* Now find the locations in the new layout */
4345 __raid10_find_phys(&conf
->geo
, r10_bio
);
4348 read_bio
->bi_next
= NULL
;
4350 for (s
= 0; s
< conf
->copies
*2; s
++) {
4352 int d
= r10_bio
->devs
[s
/2].devnum
;
4353 struct md_rdev
*rdev2
;
4355 rdev2
= conf
->mirrors
[d
].replacement
;
4356 b
= r10_bio
->devs
[s
/2].repl_bio
;
4358 rdev2
= conf
->mirrors
[d
].rdev
;
4359 b
= r10_bio
->devs
[s
/2].bio
;
4361 if (!rdev2
|| test_bit(Faulty
, &rdev2
->flags
))
4363 b
->bi_bdev
= rdev2
->bdev
;
4364 b
->bi_sector
= r10_bio
->devs
[s
/2].addr
+ rdev2
->new_data_offset
;
4365 b
->bi_private
= r10_bio
;
4366 b
->bi_end_io
= end_reshape_write
;
4368 b
->bi_flags
&= ~(BIO_POOL_MASK
- 1);
4369 b
->bi_flags
|= 1 << BIO_UPTODATE
;
4377 /* Now add as many pages as possible to all of these bios. */
4380 for (s
= 0 ; s
< max_sectors
; s
+= PAGE_SIZE
>> 9) {
4381 struct page
*page
= r10_bio
->devs
[0].bio
->bi_io_vec
[s
/(PAGE_SIZE
>>9)].bv_page
;
4382 int len
= (max_sectors
- s
) << 9;
4383 if (len
> PAGE_SIZE
)
4385 for (bio
= blist
; bio
; bio
= bio
->bi_next
) {
4387 if (bio_add_page(bio
, page
, len
, 0))
4390 /* Didn't fit, must stop */
4392 bio2
&& bio2
!= bio
;
4393 bio2
= bio2
->bi_next
) {
4394 /* Remove last page from this bio */
4396 bio2
->bi_size
-= len
;
4397 bio2
->bi_flags
&= ~(1<<BIO_SEG_VALID
);
4401 sector_nr
+= len
>> 9;
4402 nr_sectors
+= len
>> 9;
4405 r10_bio
->sectors
= nr_sectors
;
4407 /* Now submit the read */
4408 md_sync_acct(read_bio
->bi_bdev
, r10_bio
->sectors
);
4409 atomic_inc(&r10_bio
->remaining
);
4410 read_bio
->bi_next
= NULL
;
4411 generic_make_request(read_bio
);
4412 sector_nr
+= nr_sectors
;
4413 sectors_done
+= nr_sectors
;
4414 if (sector_nr
<= last
)
4417 /* Now that we have done the whole section we can
4418 * update reshape_progress
4420 if (mddev
->reshape_backwards
)
4421 conf
->reshape_progress
-= sectors_done
;
4423 conf
->reshape_progress
+= sectors_done
;
4425 return sectors_done
;
4428 static void end_reshape_request(struct r10bio
*r10_bio
);
4429 static int handle_reshape_read_error(struct mddev
*mddev
,
4430 struct r10bio
*r10_bio
);
4431 static void reshape_request_write(struct mddev
*mddev
, struct r10bio
*r10_bio
)
4433 /* Reshape read completed. Hopefully we have a block
4435 * If we got a read error then we do sync 1-page reads from
4436 * elsewhere until we find the data - or give up.
4438 struct r10conf
*conf
= mddev
->private;
4441 if (!test_bit(R10BIO_Uptodate
, &r10_bio
->state
))
4442 if (handle_reshape_read_error(mddev
, r10_bio
) < 0) {
4443 /* Reshape has been aborted */
4444 md_done_sync(mddev
, r10_bio
->sectors
, 0);
4448 /* We definitely have the data in the pages, schedule the
4451 atomic_set(&r10_bio
->remaining
, 1);
4452 for (s
= 0; s
< conf
->copies
*2; s
++) {
4454 int d
= r10_bio
->devs
[s
/2].devnum
;
4455 struct md_rdev
*rdev
;
4457 rdev
= conf
->mirrors
[d
].replacement
;
4458 b
= r10_bio
->devs
[s
/2].repl_bio
;
4460 rdev
= conf
->mirrors
[d
].rdev
;
4461 b
= r10_bio
->devs
[s
/2].bio
;
4463 if (!rdev
|| test_bit(Faulty
, &rdev
->flags
))
4465 atomic_inc(&rdev
->nr_pending
);
4466 md_sync_acct(b
->bi_bdev
, r10_bio
->sectors
);
4467 atomic_inc(&r10_bio
->remaining
);
4469 generic_make_request(b
);
4471 end_reshape_request(r10_bio
);
4474 static void end_reshape(struct r10conf
*conf
)
4476 if (test_bit(MD_RECOVERY_INTR
, &conf
->mddev
->recovery
))
4479 spin_lock_irq(&conf
->device_lock
);
4480 conf
->prev
= conf
->geo
;
4481 md_finish_reshape(conf
->mddev
);
4483 conf
->reshape_progress
= MaxSector
;
4484 spin_unlock_irq(&conf
->device_lock
);
4486 /* read-ahead size must cover two whole stripes, which is
4487 * 2 * (datadisks) * chunksize where 'n' is the number of raid devices
4489 if (conf
->mddev
->queue
) {
4490 int stripe
= conf
->geo
.raid_disks
*
4491 ((conf
->mddev
->chunk_sectors
<< 9) / PAGE_SIZE
);
4492 stripe
/= conf
->geo
.near_copies
;
4493 if (conf
->mddev
->queue
->backing_dev_info
.ra_pages
< 2 * stripe
)
4494 conf
->mddev
->queue
->backing_dev_info
.ra_pages
= 2 * stripe
;
4500 static int handle_reshape_read_error(struct mddev
*mddev
,
4501 struct r10bio
*r10_bio
)
4503 /* Use sync reads to get the blocks from somewhere else */
4504 int sectors
= r10_bio
->sectors
;
4505 struct r10conf
*conf
= mddev
->private;
4507 struct r10bio r10_bio
;
4508 struct r10dev devs
[conf
->copies
];
4510 struct r10bio
*r10b
= &on_stack
.r10_bio
;
4513 struct bio_vec
*bvec
= r10_bio
->master_bio
->bi_io_vec
;
4515 r10b
->sector
= r10_bio
->sector
;
4516 __raid10_find_phys(&conf
->prev
, r10b
);
4521 int first_slot
= slot
;
4523 if (s
> (PAGE_SIZE
>> 9))
4527 int d
= r10b
->devs
[slot
].devnum
;
4528 struct md_rdev
*rdev
= conf
->mirrors
[d
].rdev
;
4531 test_bit(Faulty
, &rdev
->flags
) ||
4532 !test_bit(In_sync
, &rdev
->flags
))
4535 addr
= r10b
->devs
[slot
].addr
+ idx
* PAGE_SIZE
;
4536 success
= sync_page_io(rdev
,
4545 if (slot
>= conf
->copies
)
4547 if (slot
== first_slot
)
4551 /* couldn't read this block, must give up */
4552 set_bit(MD_RECOVERY_INTR
,
4562 static void end_reshape_write(struct bio
*bio
, int error
)
4564 int uptodate
= test_bit(BIO_UPTODATE
, &bio
->bi_flags
);
4565 struct r10bio
*r10_bio
= bio
->bi_private
;
4566 struct mddev
*mddev
= r10_bio
->mddev
;
4567 struct r10conf
*conf
= mddev
->private;
4571 struct md_rdev
*rdev
= NULL
;
4573 d
= find_bio_disk(conf
, r10_bio
, bio
, &slot
, &repl
);
4575 rdev
= conf
->mirrors
[d
].replacement
;
4578 rdev
= conf
->mirrors
[d
].rdev
;
4582 /* FIXME should record badblock */
4583 md_error(mddev
, rdev
);
4586 rdev_dec_pending(rdev
, mddev
);
4587 end_reshape_request(r10_bio
);
4590 static void end_reshape_request(struct r10bio
*r10_bio
)
4592 if (!atomic_dec_and_test(&r10_bio
->remaining
))
4594 md_done_sync(r10_bio
->mddev
, r10_bio
->sectors
, 1);
4595 bio_put(r10_bio
->master_bio
);
4599 static void raid10_finish_reshape(struct mddev
*mddev
)
4601 struct r10conf
*conf
= mddev
->private;
4603 if (test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
))
4606 if (mddev
->delta_disks
> 0) {
4607 sector_t size
= raid10_size(mddev
, 0, 0);
4608 md_set_array_sectors(mddev
, size
);
4609 if (mddev
->recovery_cp
> mddev
->resync_max_sectors
) {
4610 mddev
->recovery_cp
= mddev
->resync_max_sectors
;
4611 set_bit(MD_RECOVERY_NEEDED
, &mddev
->recovery
);
4613 mddev
->resync_max_sectors
= size
;
4614 set_capacity(mddev
->gendisk
, mddev
->array_sectors
);
4615 revalidate_disk(mddev
->gendisk
);
4618 for (d
= conf
->geo
.raid_disks
;
4619 d
< conf
->geo
.raid_disks
- mddev
->delta_disks
;
4621 struct md_rdev
*rdev
= conf
->mirrors
[d
].rdev
;
4623 clear_bit(In_sync
, &rdev
->flags
);
4624 rdev
= conf
->mirrors
[d
].replacement
;
4626 clear_bit(In_sync
, &rdev
->flags
);
4629 mddev
->layout
= mddev
->new_layout
;
4630 mddev
->chunk_sectors
= 1 << conf
->geo
.chunk_shift
;
4631 mddev
->reshape_position
= MaxSector
;
4632 mddev
->delta_disks
= 0;
4633 mddev
->reshape_backwards
= 0;
4636 static struct md_personality raid10_personality
=
4640 .owner
= THIS_MODULE
,
4641 .make_request
= make_request
,
4645 .error_handler
= error
,
4646 .hot_add_disk
= raid10_add_disk
,
4647 .hot_remove_disk
= raid10_remove_disk
,
4648 .spare_active
= raid10_spare_active
,
4649 .sync_request
= sync_request
,
4650 .quiesce
= raid10_quiesce
,
4651 .size
= raid10_size
,
4652 .resize
= raid10_resize
,
4653 .takeover
= raid10_takeover
,
4654 .check_reshape
= raid10_check_reshape
,
4655 .start_reshape
= raid10_start_reshape
,
4656 .finish_reshape
= raid10_finish_reshape
,
4659 static int __init
raid_init(void)
4661 return register_md_personality(&raid10_personality
);
4664 static void raid_exit(void)
4666 unregister_md_personality(&raid10_personality
);
4669 module_init(raid_init
);
4670 module_exit(raid_exit
);
4671 MODULE_LICENSE("GPL");
4672 MODULE_DESCRIPTION("RAID10 (striped mirror) personality for MD");
4673 MODULE_ALIAS("md-personality-9"); /* RAID10 */
4674 MODULE_ALIAS("md-raid10");
4675 MODULE_ALIAS("md-level-10");
4677 module_param(max_queued_requests
, int, S_IRUGO
|S_IWUSR
);