2 * raid5.c : Multiple Devices driver for Linux
3 * Copyright (C) 1996, 1997 Ingo Molnar, Miguel de Icaza, Gadi Oxman
4 * Copyright (C) 1999, 2000 Ingo Molnar
5 * Copyright (C) 2002, 2003 H. Peter Anvin
7 * RAID-4/5/6 management functions.
8 * Thanks to Penguin Computing for making the RAID-6 development possible
9 * by donating a test server!
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.
24 * The sequencing for updating the bitmap reliably is a little
25 * subtle (and I got it wrong the first time) so it deserves some
28 * We group bitmap updates into batches. Each batch has a number.
29 * We may write out several batches at once, but that isn't very important.
30 * conf->seq_write is the number of the last batch successfully written.
31 * conf->seq_flush is the number of the last batch that was closed to
33 * When we discover that we will need to write to any block in a stripe
34 * (in add_stripe_bio) we update the in-memory bitmap and record in sh->bm_seq
35 * the number of the batch it will be in. This is seq_flush+1.
36 * When we are ready to do a write, if that batch hasn't been written yet,
37 * we plug the array and queue the stripe for later.
38 * When an unplug happens, we increment bm_flush, thus closing the current
40 * When we notice that bm_flush > bm_write, we write out all pending updates
41 * to the bitmap, and advance bm_write to where bm_flush was.
42 * This may occasionally write a bit out twice, but is sure never to
46 #include <linux/blkdev.h>
47 #include <linux/kthread.h>
48 #include <linux/raid/pq.h>
49 #include <linux/async_tx.h>
50 #include <linux/module.h>
51 #include <linux/async.h>
52 #include <linux/seq_file.h>
53 #include <linux/cpu.h>
54 #include <linux/slab.h>
55 #include <linux/ratelimit.h>
56 #include <linux/nodemask.h>
57 #include <trace/events/block.h>
64 #define cpu_to_group(cpu) cpu_to_node(cpu)
65 #define ANY_GROUP NUMA_NO_NODE
67 static struct workqueue_struct
*raid5_wq
;
72 #define NR_STRIPES 256
73 #define STRIPE_SIZE PAGE_SIZE
74 #define STRIPE_SHIFT (PAGE_SHIFT - 9)
75 #define STRIPE_SECTORS (STRIPE_SIZE>>9)
76 #define IO_THRESHOLD 1
77 #define BYPASS_THRESHOLD 1
78 #define NR_HASH (PAGE_SIZE / sizeof(struct hlist_head))
79 #define HASH_MASK (NR_HASH - 1)
80 #define MAX_STRIPE_BATCH 8
82 static inline struct hlist_head
*stripe_hash(struct r5conf
*conf
, sector_t sect
)
84 int hash
= (sect
>> STRIPE_SHIFT
) & HASH_MASK
;
85 return &conf
->stripe_hashtbl
[hash
];
88 static inline int stripe_hash_locks_hash(sector_t sect
)
90 return (sect
>> STRIPE_SHIFT
) & STRIPE_HASH_LOCKS_MASK
;
93 static inline void lock_device_hash_lock(struct r5conf
*conf
, int hash
)
95 spin_lock_irq(conf
->hash_locks
+ hash
);
96 spin_lock(&conf
->device_lock
);
99 static inline void unlock_device_hash_lock(struct r5conf
*conf
, int hash
)
101 spin_unlock(&conf
->device_lock
);
102 spin_unlock_irq(conf
->hash_locks
+ hash
);
105 static inline void lock_all_device_hash_locks_irq(struct r5conf
*conf
)
109 spin_lock(conf
->hash_locks
);
110 for (i
= 1; i
< NR_STRIPE_HASH_LOCKS
; i
++)
111 spin_lock_nest_lock(conf
->hash_locks
+ i
, conf
->hash_locks
);
112 spin_lock(&conf
->device_lock
);
115 static inline void unlock_all_device_hash_locks_irq(struct r5conf
*conf
)
118 spin_unlock(&conf
->device_lock
);
119 for (i
= NR_STRIPE_HASH_LOCKS
; i
; i
--)
120 spin_unlock(conf
->hash_locks
+ i
- 1);
124 /* bio's attached to a stripe+device for I/O are linked together in bi_sector
125 * order without overlap. There may be several bio's per stripe+device, and
126 * a bio could span several devices.
127 * When walking this list for a particular stripe+device, we must never proceed
128 * beyond a bio that extends past this device, as the next bio might no longer
130 * This function is used to determine the 'next' bio in the list, given the sector
131 * of the current stripe+device
133 static inline struct bio
*r5_next_bio(struct bio
*bio
, sector_t sector
)
135 int sectors
= bio_sectors(bio
);
136 if (bio
->bi_iter
.bi_sector
+ sectors
< sector
+ STRIPE_SECTORS
)
143 * We maintain a biased count of active stripes in the bottom 16 bits of
144 * bi_phys_segments, and a count of processed stripes in the upper 16 bits
146 static inline int raid5_bi_processed_stripes(struct bio
*bio
)
148 atomic_t
*segments
= (atomic_t
*)&bio
->bi_phys_segments
;
149 return (atomic_read(segments
) >> 16) & 0xffff;
152 static inline int raid5_dec_bi_active_stripes(struct bio
*bio
)
154 atomic_t
*segments
= (atomic_t
*)&bio
->bi_phys_segments
;
155 return atomic_sub_return(1, segments
) & 0xffff;
158 static inline void raid5_inc_bi_active_stripes(struct bio
*bio
)
160 atomic_t
*segments
= (atomic_t
*)&bio
->bi_phys_segments
;
161 atomic_inc(segments
);
164 static inline void raid5_set_bi_processed_stripes(struct bio
*bio
,
167 atomic_t
*segments
= (atomic_t
*)&bio
->bi_phys_segments
;
171 old
= atomic_read(segments
);
172 new = (old
& 0xffff) | (cnt
<< 16);
173 } while (atomic_cmpxchg(segments
, old
, new) != old
);
176 static inline void raid5_set_bi_stripes(struct bio
*bio
, unsigned int cnt
)
178 atomic_t
*segments
= (atomic_t
*)&bio
->bi_phys_segments
;
179 atomic_set(segments
, cnt
);
182 /* Find first data disk in a raid6 stripe */
183 static inline int raid6_d0(struct stripe_head
*sh
)
186 /* ddf always start from first device */
188 /* md starts just after Q block */
189 if (sh
->qd_idx
== sh
->disks
- 1)
192 return sh
->qd_idx
+ 1;
194 static inline int raid6_next_disk(int disk
, int raid_disks
)
197 return (disk
< raid_disks
) ? disk
: 0;
200 /* When walking through the disks in a raid5, starting at raid6_d0,
201 * We need to map each disk to a 'slot', where the data disks are slot
202 * 0 .. raid_disks-3, the parity disk is raid_disks-2 and the Q disk
203 * is raid_disks-1. This help does that mapping.
205 static int raid6_idx_to_slot(int idx
, struct stripe_head
*sh
,
206 int *count
, int syndrome_disks
)
212 if (idx
== sh
->pd_idx
)
213 return syndrome_disks
;
214 if (idx
== sh
->qd_idx
)
215 return syndrome_disks
+ 1;
221 static void return_io(struct bio
*return_bi
)
223 struct bio
*bi
= return_bi
;
226 return_bi
= bi
->bi_next
;
228 bi
->bi_iter
.bi_size
= 0;
229 trace_block_bio_complete(bdev_get_queue(bi
->bi_bdev
),
236 static void print_raid5_conf (struct r5conf
*conf
);
238 static int stripe_operations_active(struct stripe_head
*sh
)
240 return sh
->check_state
|| sh
->reconstruct_state
||
241 test_bit(STRIPE_BIOFILL_RUN
, &sh
->state
) ||
242 test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
245 static void raid5_wakeup_stripe_thread(struct stripe_head
*sh
)
247 struct r5conf
*conf
= sh
->raid_conf
;
248 struct r5worker_group
*group
;
250 int i
, cpu
= sh
->cpu
;
252 if (!cpu_online(cpu
)) {
253 cpu
= cpumask_any(cpu_online_mask
);
257 if (list_empty(&sh
->lru
)) {
258 struct r5worker_group
*group
;
259 group
= conf
->worker_groups
+ cpu_to_group(cpu
);
260 list_add_tail(&sh
->lru
, &group
->handle_list
);
261 group
->stripes_cnt
++;
265 if (conf
->worker_cnt_per_group
== 0) {
266 md_wakeup_thread(conf
->mddev
->thread
);
270 group
= conf
->worker_groups
+ cpu_to_group(sh
->cpu
);
272 group
->workers
[0].working
= true;
273 /* at least one worker should run to avoid race */
274 queue_work_on(sh
->cpu
, raid5_wq
, &group
->workers
[0].work
);
276 thread_cnt
= group
->stripes_cnt
/ MAX_STRIPE_BATCH
- 1;
277 /* wakeup more workers */
278 for (i
= 1; i
< conf
->worker_cnt_per_group
&& thread_cnt
> 0; i
++) {
279 if (group
->workers
[i
].working
== false) {
280 group
->workers
[i
].working
= true;
281 queue_work_on(sh
->cpu
, raid5_wq
,
282 &group
->workers
[i
].work
);
288 static void do_release_stripe(struct r5conf
*conf
, struct stripe_head
*sh
,
289 struct list_head
*temp_inactive_list
)
291 BUG_ON(!list_empty(&sh
->lru
));
292 BUG_ON(atomic_read(&conf
->active_stripes
)==0);
293 if (test_bit(STRIPE_HANDLE
, &sh
->state
)) {
294 if (test_bit(STRIPE_DELAYED
, &sh
->state
) &&
295 !test_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
)) {
296 list_add_tail(&sh
->lru
, &conf
->delayed_list
);
297 if (atomic_read(&conf
->preread_active_stripes
)
299 md_wakeup_thread(conf
->mddev
->thread
);
300 } else if (test_bit(STRIPE_BIT_DELAY
, &sh
->state
) &&
301 sh
->bm_seq
- conf
->seq_write
> 0)
302 list_add_tail(&sh
->lru
, &conf
->bitmap_list
);
304 clear_bit(STRIPE_DELAYED
, &sh
->state
);
305 clear_bit(STRIPE_BIT_DELAY
, &sh
->state
);
306 if (conf
->worker_cnt_per_group
== 0) {
307 list_add_tail(&sh
->lru
, &conf
->handle_list
);
309 raid5_wakeup_stripe_thread(sh
);
313 md_wakeup_thread(conf
->mddev
->thread
);
315 BUG_ON(stripe_operations_active(sh
));
316 if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
317 if (atomic_dec_return(&conf
->preread_active_stripes
)
319 md_wakeup_thread(conf
->mddev
->thread
);
320 atomic_dec(&conf
->active_stripes
);
321 if (!test_bit(STRIPE_EXPANDING
, &sh
->state
))
322 list_add_tail(&sh
->lru
, temp_inactive_list
);
326 static void __release_stripe(struct r5conf
*conf
, struct stripe_head
*sh
,
327 struct list_head
*temp_inactive_list
)
329 if (atomic_dec_and_test(&sh
->count
))
330 do_release_stripe(conf
, sh
, temp_inactive_list
);
334 * @hash could be NR_STRIPE_HASH_LOCKS, then we have a list of inactive_list
336 * Be careful: Only one task can add/delete stripes from temp_inactive_list at
337 * given time. Adding stripes only takes device lock, while deleting stripes
338 * only takes hash lock.
340 static void release_inactive_stripe_list(struct r5conf
*conf
,
341 struct list_head
*temp_inactive_list
,
345 bool do_wakeup
= false;
348 if (hash
== NR_STRIPE_HASH_LOCKS
) {
349 size
= NR_STRIPE_HASH_LOCKS
;
350 hash
= NR_STRIPE_HASH_LOCKS
- 1;
354 struct list_head
*list
= &temp_inactive_list
[size
- 1];
357 * We don't hold any lock here yet, get_active_stripe() might
358 * remove stripes from the list
360 if (!list_empty_careful(list
)) {
361 spin_lock_irqsave(conf
->hash_locks
+ hash
, flags
);
362 if (list_empty(conf
->inactive_list
+ hash
) &&
364 atomic_dec(&conf
->empty_inactive_list_nr
);
365 list_splice_tail_init(list
, conf
->inactive_list
+ hash
);
367 spin_unlock_irqrestore(conf
->hash_locks
+ hash
, flags
);
374 wake_up(&conf
->wait_for_stripe
);
375 if (conf
->retry_read_aligned
)
376 md_wakeup_thread(conf
->mddev
->thread
);
380 /* should hold conf->device_lock already */
381 static int release_stripe_list(struct r5conf
*conf
,
382 struct list_head
*temp_inactive_list
)
384 struct stripe_head
*sh
;
386 struct llist_node
*head
;
388 head
= llist_del_all(&conf
->released_stripes
);
389 head
= llist_reverse_order(head
);
393 sh
= llist_entry(head
, struct stripe_head
, release_list
);
394 head
= llist_next(head
);
395 /* sh could be readded after STRIPE_ON_RELEASE_LIST is cleard */
397 clear_bit(STRIPE_ON_RELEASE_LIST
, &sh
->state
);
399 * Don't worry the bit is set here, because if the bit is set
400 * again, the count is always > 1. This is true for
401 * STRIPE_ON_UNPLUG_LIST bit too.
403 hash
= sh
->hash_lock_index
;
404 __release_stripe(conf
, sh
, &temp_inactive_list
[hash
]);
411 static void release_stripe(struct stripe_head
*sh
)
413 struct r5conf
*conf
= sh
->raid_conf
;
415 struct list_head list
;
419 /* Avoid release_list until the last reference.
421 if (atomic_add_unless(&sh
->count
, -1, 1))
424 if (unlikely(!conf
->mddev
->thread
) ||
425 test_and_set_bit(STRIPE_ON_RELEASE_LIST
, &sh
->state
))
427 wakeup
= llist_add(&sh
->release_list
, &conf
->released_stripes
);
429 md_wakeup_thread(conf
->mddev
->thread
);
432 local_irq_save(flags
);
433 /* we are ok here if STRIPE_ON_RELEASE_LIST is set or not */
434 if (atomic_dec_and_lock(&sh
->count
, &conf
->device_lock
)) {
435 INIT_LIST_HEAD(&list
);
436 hash
= sh
->hash_lock_index
;
437 do_release_stripe(conf
, sh
, &list
);
438 spin_unlock(&conf
->device_lock
);
439 release_inactive_stripe_list(conf
, &list
, hash
);
441 local_irq_restore(flags
);
444 static inline void remove_hash(struct stripe_head
*sh
)
446 pr_debug("remove_hash(), stripe %llu\n",
447 (unsigned long long)sh
->sector
);
449 hlist_del_init(&sh
->hash
);
452 static inline void insert_hash(struct r5conf
*conf
, struct stripe_head
*sh
)
454 struct hlist_head
*hp
= stripe_hash(conf
, sh
->sector
);
456 pr_debug("insert_hash(), stripe %llu\n",
457 (unsigned long long)sh
->sector
);
459 hlist_add_head(&sh
->hash
, hp
);
463 /* find an idle stripe, make sure it is unhashed, and return it. */
464 static struct stripe_head
*get_free_stripe(struct r5conf
*conf
, int hash
)
466 struct stripe_head
*sh
= NULL
;
467 struct list_head
*first
;
469 if (list_empty(conf
->inactive_list
+ hash
))
471 first
= (conf
->inactive_list
+ hash
)->next
;
472 sh
= list_entry(first
, struct stripe_head
, lru
);
473 list_del_init(first
);
475 atomic_inc(&conf
->active_stripes
);
476 BUG_ON(hash
!= sh
->hash_lock_index
);
477 if (list_empty(conf
->inactive_list
+ hash
))
478 atomic_inc(&conf
->empty_inactive_list_nr
);
483 static void shrink_buffers(struct stripe_head
*sh
)
487 int num
= sh
->raid_conf
->pool_size
;
489 for (i
= 0; i
< num
; i
++) {
490 WARN_ON(sh
->dev
[i
].page
!= sh
->dev
[i
].orig_page
);
494 sh
->dev
[i
].page
= NULL
;
499 static int grow_buffers(struct stripe_head
*sh
)
502 int num
= sh
->raid_conf
->pool_size
;
504 for (i
= 0; i
< num
; i
++) {
507 if (!(page
= alloc_page(GFP_KERNEL
))) {
510 sh
->dev
[i
].page
= page
;
511 sh
->dev
[i
].orig_page
= page
;
516 static void raid5_build_block(struct stripe_head
*sh
, int i
, int previous
);
517 static void stripe_set_idx(sector_t stripe
, struct r5conf
*conf
, int previous
,
518 struct stripe_head
*sh
);
520 static void init_stripe(struct stripe_head
*sh
, sector_t sector
, int previous
)
522 struct r5conf
*conf
= sh
->raid_conf
;
525 BUG_ON(atomic_read(&sh
->count
) != 0);
526 BUG_ON(test_bit(STRIPE_HANDLE
, &sh
->state
));
527 BUG_ON(stripe_operations_active(sh
));
529 pr_debug("init_stripe called, stripe %llu\n",
530 (unsigned long long)sh
->sector
);
534 seq
= read_seqcount_begin(&conf
->gen_lock
);
535 sh
->generation
= conf
->generation
- previous
;
536 sh
->disks
= previous
? conf
->previous_raid_disks
: conf
->raid_disks
;
538 stripe_set_idx(sector
, conf
, previous
, sh
);
542 for (i
= sh
->disks
; i
--; ) {
543 struct r5dev
*dev
= &sh
->dev
[i
];
545 if (dev
->toread
|| dev
->read
|| dev
->towrite
|| dev
->written
||
546 test_bit(R5_LOCKED
, &dev
->flags
)) {
547 printk(KERN_ERR
"sector=%llx i=%d %p %p %p %p %d\n",
548 (unsigned long long)sh
->sector
, i
, dev
->toread
,
549 dev
->read
, dev
->towrite
, dev
->written
,
550 test_bit(R5_LOCKED
, &dev
->flags
));
554 raid5_build_block(sh
, i
, previous
);
556 if (read_seqcount_retry(&conf
->gen_lock
, seq
))
558 insert_hash(conf
, sh
);
559 sh
->cpu
= smp_processor_id();
562 static struct stripe_head
*__find_stripe(struct r5conf
*conf
, sector_t sector
,
565 struct stripe_head
*sh
;
567 pr_debug("__find_stripe, sector %llu\n", (unsigned long long)sector
);
568 hlist_for_each_entry(sh
, stripe_hash(conf
, sector
), hash
)
569 if (sh
->sector
== sector
&& sh
->generation
== generation
)
571 pr_debug("__stripe %llu not in cache\n", (unsigned long long)sector
);
576 * Need to check if array has failed when deciding whether to:
578 * - remove non-faulty devices
581 * This determination is simple when no reshape is happening.
582 * However if there is a reshape, we need to carefully check
583 * both the before and after sections.
584 * This is because some failed devices may only affect one
585 * of the two sections, and some non-in_sync devices may
586 * be insync in the section most affected by failed devices.
588 static int calc_degraded(struct r5conf
*conf
)
590 int degraded
, degraded2
;
595 for (i
= 0; i
< conf
->previous_raid_disks
; i
++) {
596 struct md_rdev
*rdev
= rcu_dereference(conf
->disks
[i
].rdev
);
597 if (rdev
&& test_bit(Faulty
, &rdev
->flags
))
598 rdev
= rcu_dereference(conf
->disks
[i
].replacement
);
599 if (!rdev
|| test_bit(Faulty
, &rdev
->flags
))
601 else if (test_bit(In_sync
, &rdev
->flags
))
604 /* not in-sync or faulty.
605 * If the reshape increases the number of devices,
606 * this is being recovered by the reshape, so
607 * this 'previous' section is not in_sync.
608 * If the number of devices is being reduced however,
609 * the device can only be part of the array if
610 * we are reverting a reshape, so this section will
613 if (conf
->raid_disks
>= conf
->previous_raid_disks
)
617 if (conf
->raid_disks
== conf
->previous_raid_disks
)
621 for (i
= 0; i
< conf
->raid_disks
; i
++) {
622 struct md_rdev
*rdev
= rcu_dereference(conf
->disks
[i
].rdev
);
623 if (rdev
&& test_bit(Faulty
, &rdev
->flags
))
624 rdev
= rcu_dereference(conf
->disks
[i
].replacement
);
625 if (!rdev
|| test_bit(Faulty
, &rdev
->flags
))
627 else if (test_bit(In_sync
, &rdev
->flags
))
630 /* not in-sync or faulty.
631 * If reshape increases the number of devices, this
632 * section has already been recovered, else it
633 * almost certainly hasn't.
635 if (conf
->raid_disks
<= conf
->previous_raid_disks
)
639 if (degraded2
> degraded
)
644 static int has_failed(struct r5conf
*conf
)
648 if (conf
->mddev
->reshape_position
== MaxSector
)
649 return conf
->mddev
->degraded
> conf
->max_degraded
;
651 degraded
= calc_degraded(conf
);
652 if (degraded
> conf
->max_degraded
)
657 static struct stripe_head
*
658 get_active_stripe(struct r5conf
*conf
, sector_t sector
,
659 int previous
, int noblock
, int noquiesce
)
661 struct stripe_head
*sh
;
662 int hash
= stripe_hash_locks_hash(sector
);
664 pr_debug("get_stripe, sector %llu\n", (unsigned long long)sector
);
666 spin_lock_irq(conf
->hash_locks
+ hash
);
669 wait_event_lock_irq(conf
->wait_for_stripe
,
670 conf
->quiesce
== 0 || noquiesce
,
671 *(conf
->hash_locks
+ hash
));
672 sh
= __find_stripe(conf
, sector
, conf
->generation
- previous
);
674 if (!conf
->inactive_blocked
)
675 sh
= get_free_stripe(conf
, hash
);
676 if (noblock
&& sh
== NULL
)
679 conf
->inactive_blocked
= 1;
681 conf
->wait_for_stripe
,
682 !list_empty(conf
->inactive_list
+ hash
) &&
683 (atomic_read(&conf
->active_stripes
)
684 < (conf
->max_nr_stripes
* 3 / 4)
685 || !conf
->inactive_blocked
),
686 *(conf
->hash_locks
+ hash
));
687 conf
->inactive_blocked
= 0;
689 init_stripe(sh
, sector
, previous
);
690 atomic_inc(&sh
->count
);
692 } else if (!atomic_inc_not_zero(&sh
->count
)) {
693 spin_lock(&conf
->device_lock
);
694 if (!atomic_read(&sh
->count
)) {
695 if (!test_bit(STRIPE_HANDLE
, &sh
->state
))
696 atomic_inc(&conf
->active_stripes
);
697 BUG_ON(list_empty(&sh
->lru
) &&
698 !test_bit(STRIPE_EXPANDING
, &sh
->state
));
699 list_del_init(&sh
->lru
);
701 sh
->group
->stripes_cnt
--;
705 atomic_inc(&sh
->count
);
706 spin_unlock(&conf
->device_lock
);
708 } while (sh
== NULL
);
710 spin_unlock_irq(conf
->hash_locks
+ hash
);
714 /* Determine if 'data_offset' or 'new_data_offset' should be used
715 * in this stripe_head.
717 static int use_new_offset(struct r5conf
*conf
, struct stripe_head
*sh
)
719 sector_t progress
= conf
->reshape_progress
;
720 /* Need a memory barrier to make sure we see the value
721 * of conf->generation, or ->data_offset that was set before
722 * reshape_progress was updated.
725 if (progress
== MaxSector
)
727 if (sh
->generation
== conf
->generation
- 1)
729 /* We are in a reshape, and this is a new-generation stripe,
730 * so use new_data_offset.
736 raid5_end_read_request(struct bio
*bi
, int error
);
738 raid5_end_write_request(struct bio
*bi
, int error
);
740 static void ops_run_io(struct stripe_head
*sh
, struct stripe_head_state
*s
)
742 struct r5conf
*conf
= sh
->raid_conf
;
743 int i
, disks
= sh
->disks
;
747 for (i
= disks
; i
--; ) {
749 int replace_only
= 0;
750 struct bio
*bi
, *rbi
;
751 struct md_rdev
*rdev
, *rrdev
= NULL
;
752 if (test_and_clear_bit(R5_Wantwrite
, &sh
->dev
[i
].flags
)) {
753 if (test_and_clear_bit(R5_WantFUA
, &sh
->dev
[i
].flags
))
757 if (test_bit(R5_Discard
, &sh
->dev
[i
].flags
))
759 } else if (test_and_clear_bit(R5_Wantread
, &sh
->dev
[i
].flags
))
761 else if (test_and_clear_bit(R5_WantReplace
,
762 &sh
->dev
[i
].flags
)) {
767 if (test_and_clear_bit(R5_SyncIO
, &sh
->dev
[i
].flags
))
770 bi
= &sh
->dev
[i
].req
;
771 rbi
= &sh
->dev
[i
].rreq
; /* For writing to replacement */
774 rrdev
= rcu_dereference(conf
->disks
[i
].replacement
);
775 smp_mb(); /* Ensure that if rrdev is NULL, rdev won't be */
776 rdev
= rcu_dereference(conf
->disks
[i
].rdev
);
785 /* We raced and saw duplicates */
788 if (test_bit(R5_ReadRepl
, &sh
->dev
[i
].flags
) && rrdev
)
793 if (rdev
&& test_bit(Faulty
, &rdev
->flags
))
796 atomic_inc(&rdev
->nr_pending
);
797 if (rrdev
&& test_bit(Faulty
, &rrdev
->flags
))
800 atomic_inc(&rrdev
->nr_pending
);
803 /* We have already checked bad blocks for reads. Now
804 * need to check for writes. We never accept write errors
805 * on the replacement, so we don't to check rrdev.
807 while ((rw
& WRITE
) && rdev
&&
808 test_bit(WriteErrorSeen
, &rdev
->flags
)) {
811 int bad
= is_badblock(rdev
, sh
->sector
, STRIPE_SECTORS
,
812 &first_bad
, &bad_sectors
);
817 set_bit(BlockedBadBlocks
, &rdev
->flags
);
818 if (!conf
->mddev
->external
&&
819 conf
->mddev
->flags
) {
820 /* It is very unlikely, but we might
821 * still need to write out the
822 * bad block log - better give it
824 md_check_recovery(conf
->mddev
);
827 * Because md_wait_for_blocked_rdev
828 * will dec nr_pending, we must
829 * increment it first.
831 atomic_inc(&rdev
->nr_pending
);
832 md_wait_for_blocked_rdev(rdev
, conf
->mddev
);
834 /* Acknowledged bad block - skip the write */
835 rdev_dec_pending(rdev
, conf
->mddev
);
841 if (s
->syncing
|| s
->expanding
|| s
->expanded
843 md_sync_acct(rdev
->bdev
, STRIPE_SECTORS
);
845 set_bit(STRIPE_IO_STARTED
, &sh
->state
);
848 bi
->bi_bdev
= rdev
->bdev
;
850 bi
->bi_end_io
= (rw
& WRITE
)
851 ? raid5_end_write_request
852 : raid5_end_read_request
;
855 pr_debug("%s: for %llu schedule op %ld on disc %d\n",
856 __func__
, (unsigned long long)sh
->sector
,
858 atomic_inc(&sh
->count
);
859 if (use_new_offset(conf
, sh
))
860 bi
->bi_iter
.bi_sector
= (sh
->sector
861 + rdev
->new_data_offset
);
863 bi
->bi_iter
.bi_sector
= (sh
->sector
864 + rdev
->data_offset
);
865 if (test_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
))
866 bi
->bi_rw
|= REQ_NOMERGE
;
868 if (test_bit(R5_SkipCopy
, &sh
->dev
[i
].flags
))
869 WARN_ON(test_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
));
870 sh
->dev
[i
].vec
.bv_page
= sh
->dev
[i
].page
;
872 bi
->bi_io_vec
[0].bv_len
= STRIPE_SIZE
;
873 bi
->bi_io_vec
[0].bv_offset
= 0;
874 bi
->bi_iter
.bi_size
= STRIPE_SIZE
;
876 * If this is discard request, set bi_vcnt 0. We don't
877 * want to confuse SCSI because SCSI will replace payload
879 if (rw
& REQ_DISCARD
)
882 set_bit(R5_DOUBLE_LOCKED
, &sh
->dev
[i
].flags
);
884 if (conf
->mddev
->gendisk
)
885 trace_block_bio_remap(bdev_get_queue(bi
->bi_bdev
),
886 bi
, disk_devt(conf
->mddev
->gendisk
),
888 generic_make_request(bi
);
891 if (s
->syncing
|| s
->expanding
|| s
->expanded
893 md_sync_acct(rrdev
->bdev
, STRIPE_SECTORS
);
895 set_bit(STRIPE_IO_STARTED
, &sh
->state
);
898 rbi
->bi_bdev
= rrdev
->bdev
;
900 BUG_ON(!(rw
& WRITE
));
901 rbi
->bi_end_io
= raid5_end_write_request
;
902 rbi
->bi_private
= sh
;
904 pr_debug("%s: for %llu schedule op %ld on "
905 "replacement disc %d\n",
906 __func__
, (unsigned long long)sh
->sector
,
908 atomic_inc(&sh
->count
);
909 if (use_new_offset(conf
, sh
))
910 rbi
->bi_iter
.bi_sector
= (sh
->sector
911 + rrdev
->new_data_offset
);
913 rbi
->bi_iter
.bi_sector
= (sh
->sector
914 + rrdev
->data_offset
);
915 if (test_bit(R5_SkipCopy
, &sh
->dev
[i
].flags
))
916 WARN_ON(test_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
));
917 sh
->dev
[i
].rvec
.bv_page
= sh
->dev
[i
].page
;
919 rbi
->bi_io_vec
[0].bv_len
= STRIPE_SIZE
;
920 rbi
->bi_io_vec
[0].bv_offset
= 0;
921 rbi
->bi_iter
.bi_size
= STRIPE_SIZE
;
923 * If this is discard request, set bi_vcnt 0. We don't
924 * want to confuse SCSI because SCSI will replace payload
926 if (rw
& REQ_DISCARD
)
928 if (conf
->mddev
->gendisk
)
929 trace_block_bio_remap(bdev_get_queue(rbi
->bi_bdev
),
930 rbi
, disk_devt(conf
->mddev
->gendisk
),
932 generic_make_request(rbi
);
934 if (!rdev
&& !rrdev
) {
936 set_bit(STRIPE_DEGRADED
, &sh
->state
);
937 pr_debug("skip op %ld on disc %d for sector %llu\n",
938 bi
->bi_rw
, i
, (unsigned long long)sh
->sector
);
939 clear_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
940 set_bit(STRIPE_HANDLE
, &sh
->state
);
945 static struct dma_async_tx_descriptor
*
946 async_copy_data(int frombio
, struct bio
*bio
, struct page
**page
,
947 sector_t sector
, struct dma_async_tx_descriptor
*tx
,
948 struct stripe_head
*sh
)
951 struct bvec_iter iter
;
952 struct page
*bio_page
;
954 struct async_submit_ctl submit
;
955 enum async_tx_flags flags
= 0;
957 if (bio
->bi_iter
.bi_sector
>= sector
)
958 page_offset
= (signed)(bio
->bi_iter
.bi_sector
- sector
) * 512;
960 page_offset
= (signed)(sector
- bio
->bi_iter
.bi_sector
) * -512;
963 flags
|= ASYNC_TX_FENCE
;
964 init_async_submit(&submit
, flags
, tx
, NULL
, NULL
, NULL
);
966 bio_for_each_segment(bvl
, bio
, iter
) {
967 int len
= bvl
.bv_len
;
971 if (page_offset
< 0) {
972 b_offset
= -page_offset
;
973 page_offset
+= b_offset
;
977 if (len
> 0 && page_offset
+ len
> STRIPE_SIZE
)
978 clen
= STRIPE_SIZE
- page_offset
;
983 b_offset
+= bvl
.bv_offset
;
984 bio_page
= bvl
.bv_page
;
986 if (sh
->raid_conf
->skip_copy
&&
987 b_offset
== 0 && page_offset
== 0 &&
991 tx
= async_memcpy(*page
, bio_page
, page_offset
,
992 b_offset
, clen
, &submit
);
994 tx
= async_memcpy(bio_page
, *page
, b_offset
,
995 page_offset
, clen
, &submit
);
997 /* chain the operations */
998 submit
.depend_tx
= tx
;
1000 if (clen
< len
) /* hit end of page */
1008 static void ops_complete_biofill(void *stripe_head_ref
)
1010 struct stripe_head
*sh
= stripe_head_ref
;
1011 struct bio
*return_bi
= NULL
;
1014 pr_debug("%s: stripe %llu\n", __func__
,
1015 (unsigned long long)sh
->sector
);
1017 /* clear completed biofills */
1018 for (i
= sh
->disks
; i
--; ) {
1019 struct r5dev
*dev
= &sh
->dev
[i
];
1021 /* acknowledge completion of a biofill operation */
1022 /* and check if we need to reply to a read request,
1023 * new R5_Wantfill requests are held off until
1024 * !STRIPE_BIOFILL_RUN
1026 if (test_and_clear_bit(R5_Wantfill
, &dev
->flags
)) {
1027 struct bio
*rbi
, *rbi2
;
1032 while (rbi
&& rbi
->bi_iter
.bi_sector
<
1033 dev
->sector
+ STRIPE_SECTORS
) {
1034 rbi2
= r5_next_bio(rbi
, dev
->sector
);
1035 if (!raid5_dec_bi_active_stripes(rbi
)) {
1036 rbi
->bi_next
= return_bi
;
1043 clear_bit(STRIPE_BIOFILL_RUN
, &sh
->state
);
1045 return_io(return_bi
);
1047 set_bit(STRIPE_HANDLE
, &sh
->state
);
1051 static void ops_run_biofill(struct stripe_head
*sh
)
1053 struct dma_async_tx_descriptor
*tx
= NULL
;
1054 struct async_submit_ctl submit
;
1057 pr_debug("%s: stripe %llu\n", __func__
,
1058 (unsigned long long)sh
->sector
);
1060 for (i
= sh
->disks
; i
--; ) {
1061 struct r5dev
*dev
= &sh
->dev
[i
];
1062 if (test_bit(R5_Wantfill
, &dev
->flags
)) {
1064 spin_lock_irq(&sh
->stripe_lock
);
1065 dev
->read
= rbi
= dev
->toread
;
1067 spin_unlock_irq(&sh
->stripe_lock
);
1068 while (rbi
&& rbi
->bi_iter
.bi_sector
<
1069 dev
->sector
+ STRIPE_SECTORS
) {
1070 tx
= async_copy_data(0, rbi
, &dev
->page
,
1071 dev
->sector
, tx
, sh
);
1072 rbi
= r5_next_bio(rbi
, dev
->sector
);
1077 atomic_inc(&sh
->count
);
1078 init_async_submit(&submit
, ASYNC_TX_ACK
, tx
, ops_complete_biofill
, sh
, NULL
);
1079 async_trigger_callback(&submit
);
1082 static void mark_target_uptodate(struct stripe_head
*sh
, int target
)
1089 tgt
= &sh
->dev
[target
];
1090 set_bit(R5_UPTODATE
, &tgt
->flags
);
1091 BUG_ON(!test_bit(R5_Wantcompute
, &tgt
->flags
));
1092 clear_bit(R5_Wantcompute
, &tgt
->flags
);
1095 static void ops_complete_compute(void *stripe_head_ref
)
1097 struct stripe_head
*sh
= stripe_head_ref
;
1099 pr_debug("%s: stripe %llu\n", __func__
,
1100 (unsigned long long)sh
->sector
);
1102 /* mark the computed target(s) as uptodate */
1103 mark_target_uptodate(sh
, sh
->ops
.target
);
1104 mark_target_uptodate(sh
, sh
->ops
.target2
);
1106 clear_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
1107 if (sh
->check_state
== check_state_compute_run
)
1108 sh
->check_state
= check_state_compute_result
;
1109 set_bit(STRIPE_HANDLE
, &sh
->state
);
1113 /* return a pointer to the address conversion region of the scribble buffer */
1114 static addr_conv_t
*to_addr_conv(struct stripe_head
*sh
,
1115 struct raid5_percpu
*percpu
)
1117 return percpu
->scribble
+ sizeof(struct page
*) * (sh
->disks
+ 2);
1120 static struct dma_async_tx_descriptor
*
1121 ops_run_compute5(struct stripe_head
*sh
, struct raid5_percpu
*percpu
)
1123 int disks
= sh
->disks
;
1124 struct page
**xor_srcs
= percpu
->scribble
;
1125 int target
= sh
->ops
.target
;
1126 struct r5dev
*tgt
= &sh
->dev
[target
];
1127 struct page
*xor_dest
= tgt
->page
;
1129 struct dma_async_tx_descriptor
*tx
;
1130 struct async_submit_ctl submit
;
1133 pr_debug("%s: stripe %llu block: %d\n",
1134 __func__
, (unsigned long long)sh
->sector
, target
);
1135 BUG_ON(!test_bit(R5_Wantcompute
, &tgt
->flags
));
1137 for (i
= disks
; i
--; )
1139 xor_srcs
[count
++] = sh
->dev
[i
].page
;
1141 atomic_inc(&sh
->count
);
1143 init_async_submit(&submit
, ASYNC_TX_FENCE
|ASYNC_TX_XOR_ZERO_DST
, NULL
,
1144 ops_complete_compute
, sh
, to_addr_conv(sh
, percpu
));
1145 if (unlikely(count
== 1))
1146 tx
= async_memcpy(xor_dest
, xor_srcs
[0], 0, 0, STRIPE_SIZE
, &submit
);
1148 tx
= async_xor(xor_dest
, xor_srcs
, 0, count
, STRIPE_SIZE
, &submit
);
1153 /* set_syndrome_sources - populate source buffers for gen_syndrome
1154 * @srcs - (struct page *) array of size sh->disks
1155 * @sh - stripe_head to parse
1157 * Populates srcs in proper layout order for the stripe and returns the
1158 * 'count' of sources to be used in a call to async_gen_syndrome. The P
1159 * destination buffer is recorded in srcs[count] and the Q destination
1160 * is recorded in srcs[count+1]].
1162 static int set_syndrome_sources(struct page
**srcs
, struct stripe_head
*sh
)
1164 int disks
= sh
->disks
;
1165 int syndrome_disks
= sh
->ddf_layout
? disks
: (disks
- 2);
1166 int d0_idx
= raid6_d0(sh
);
1170 for (i
= 0; i
< disks
; i
++)
1176 int slot
= raid6_idx_to_slot(i
, sh
, &count
, syndrome_disks
);
1178 srcs
[slot
] = sh
->dev
[i
].page
;
1179 i
= raid6_next_disk(i
, disks
);
1180 } while (i
!= d0_idx
);
1182 return syndrome_disks
;
1185 static struct dma_async_tx_descriptor
*
1186 ops_run_compute6_1(struct stripe_head
*sh
, struct raid5_percpu
*percpu
)
1188 int disks
= sh
->disks
;
1189 struct page
**blocks
= percpu
->scribble
;
1191 int qd_idx
= sh
->qd_idx
;
1192 struct dma_async_tx_descriptor
*tx
;
1193 struct async_submit_ctl submit
;
1199 if (sh
->ops
.target
< 0)
1200 target
= sh
->ops
.target2
;
1201 else if (sh
->ops
.target2
< 0)
1202 target
= sh
->ops
.target
;
1204 /* we should only have one valid target */
1207 pr_debug("%s: stripe %llu block: %d\n",
1208 __func__
, (unsigned long long)sh
->sector
, target
);
1210 tgt
= &sh
->dev
[target
];
1211 BUG_ON(!test_bit(R5_Wantcompute
, &tgt
->flags
));
1214 atomic_inc(&sh
->count
);
1216 if (target
== qd_idx
) {
1217 count
= set_syndrome_sources(blocks
, sh
);
1218 blocks
[count
] = NULL
; /* regenerating p is not necessary */
1219 BUG_ON(blocks
[count
+1] != dest
); /* q should already be set */
1220 init_async_submit(&submit
, ASYNC_TX_FENCE
, NULL
,
1221 ops_complete_compute
, sh
,
1222 to_addr_conv(sh
, percpu
));
1223 tx
= async_gen_syndrome(blocks
, 0, count
+2, STRIPE_SIZE
, &submit
);
1225 /* Compute any data- or p-drive using XOR */
1227 for (i
= disks
; i
-- ; ) {
1228 if (i
== target
|| i
== qd_idx
)
1230 blocks
[count
++] = sh
->dev
[i
].page
;
1233 init_async_submit(&submit
, ASYNC_TX_FENCE
|ASYNC_TX_XOR_ZERO_DST
,
1234 NULL
, ops_complete_compute
, sh
,
1235 to_addr_conv(sh
, percpu
));
1236 tx
= async_xor(dest
, blocks
, 0, count
, STRIPE_SIZE
, &submit
);
1242 static struct dma_async_tx_descriptor
*
1243 ops_run_compute6_2(struct stripe_head
*sh
, struct raid5_percpu
*percpu
)
1245 int i
, count
, disks
= sh
->disks
;
1246 int syndrome_disks
= sh
->ddf_layout
? disks
: disks
-2;
1247 int d0_idx
= raid6_d0(sh
);
1248 int faila
= -1, failb
= -1;
1249 int target
= sh
->ops
.target
;
1250 int target2
= sh
->ops
.target2
;
1251 struct r5dev
*tgt
= &sh
->dev
[target
];
1252 struct r5dev
*tgt2
= &sh
->dev
[target2
];
1253 struct dma_async_tx_descriptor
*tx
;
1254 struct page
**blocks
= percpu
->scribble
;
1255 struct async_submit_ctl submit
;
1257 pr_debug("%s: stripe %llu block1: %d block2: %d\n",
1258 __func__
, (unsigned long long)sh
->sector
, target
, target2
);
1259 BUG_ON(target
< 0 || target2
< 0);
1260 BUG_ON(!test_bit(R5_Wantcompute
, &tgt
->flags
));
1261 BUG_ON(!test_bit(R5_Wantcompute
, &tgt2
->flags
));
1263 /* we need to open-code set_syndrome_sources to handle the
1264 * slot number conversion for 'faila' and 'failb'
1266 for (i
= 0; i
< disks
; i
++)
1271 int slot
= raid6_idx_to_slot(i
, sh
, &count
, syndrome_disks
);
1273 blocks
[slot
] = sh
->dev
[i
].page
;
1279 i
= raid6_next_disk(i
, disks
);
1280 } while (i
!= d0_idx
);
1282 BUG_ON(faila
== failb
);
1285 pr_debug("%s: stripe: %llu faila: %d failb: %d\n",
1286 __func__
, (unsigned long long)sh
->sector
, faila
, failb
);
1288 atomic_inc(&sh
->count
);
1290 if (failb
== syndrome_disks
+1) {
1291 /* Q disk is one of the missing disks */
1292 if (faila
== syndrome_disks
) {
1293 /* Missing P+Q, just recompute */
1294 init_async_submit(&submit
, ASYNC_TX_FENCE
, NULL
,
1295 ops_complete_compute
, sh
,
1296 to_addr_conv(sh
, percpu
));
1297 return async_gen_syndrome(blocks
, 0, syndrome_disks
+2,
1298 STRIPE_SIZE
, &submit
);
1302 int qd_idx
= sh
->qd_idx
;
1304 /* Missing D+Q: recompute D from P, then recompute Q */
1305 if (target
== qd_idx
)
1306 data_target
= target2
;
1308 data_target
= target
;
1311 for (i
= disks
; i
-- ; ) {
1312 if (i
== data_target
|| i
== qd_idx
)
1314 blocks
[count
++] = sh
->dev
[i
].page
;
1316 dest
= sh
->dev
[data_target
].page
;
1317 init_async_submit(&submit
,
1318 ASYNC_TX_FENCE
|ASYNC_TX_XOR_ZERO_DST
,
1320 to_addr_conv(sh
, percpu
));
1321 tx
= async_xor(dest
, blocks
, 0, count
, STRIPE_SIZE
,
1324 count
= set_syndrome_sources(blocks
, sh
);
1325 init_async_submit(&submit
, ASYNC_TX_FENCE
, tx
,
1326 ops_complete_compute
, sh
,
1327 to_addr_conv(sh
, percpu
));
1328 return async_gen_syndrome(blocks
, 0, count
+2,
1329 STRIPE_SIZE
, &submit
);
1332 init_async_submit(&submit
, ASYNC_TX_FENCE
, NULL
,
1333 ops_complete_compute
, sh
,
1334 to_addr_conv(sh
, percpu
));
1335 if (failb
== syndrome_disks
) {
1336 /* We're missing D+P. */
1337 return async_raid6_datap_recov(syndrome_disks
+2,
1341 /* We're missing D+D. */
1342 return async_raid6_2data_recov(syndrome_disks
+2,
1343 STRIPE_SIZE
, faila
, failb
,
1350 static void ops_complete_prexor(void *stripe_head_ref
)
1352 struct stripe_head
*sh
= stripe_head_ref
;
1354 pr_debug("%s: stripe %llu\n", __func__
,
1355 (unsigned long long)sh
->sector
);
1358 static struct dma_async_tx_descriptor
*
1359 ops_run_prexor(struct stripe_head
*sh
, struct raid5_percpu
*percpu
,
1360 struct dma_async_tx_descriptor
*tx
)
1362 int disks
= sh
->disks
;
1363 struct page
**xor_srcs
= percpu
->scribble
;
1364 int count
= 0, pd_idx
= sh
->pd_idx
, i
;
1365 struct async_submit_ctl submit
;
1367 /* existing parity data subtracted */
1368 struct page
*xor_dest
= xor_srcs
[count
++] = sh
->dev
[pd_idx
].page
;
1370 pr_debug("%s: stripe %llu\n", __func__
,
1371 (unsigned long long)sh
->sector
);
1373 for (i
= disks
; i
--; ) {
1374 struct r5dev
*dev
= &sh
->dev
[i
];
1375 /* Only process blocks that are known to be uptodate */
1376 if (test_bit(R5_Wantdrain
, &dev
->flags
))
1377 xor_srcs
[count
++] = dev
->page
;
1380 init_async_submit(&submit
, ASYNC_TX_FENCE
|ASYNC_TX_XOR_DROP_DST
, tx
,
1381 ops_complete_prexor
, sh
, to_addr_conv(sh
, percpu
));
1382 tx
= async_xor(xor_dest
, xor_srcs
, 0, count
, STRIPE_SIZE
, &submit
);
1387 static struct dma_async_tx_descriptor
*
1388 ops_run_biodrain(struct stripe_head
*sh
, struct dma_async_tx_descriptor
*tx
)
1390 int disks
= sh
->disks
;
1393 pr_debug("%s: stripe %llu\n", __func__
,
1394 (unsigned long long)sh
->sector
);
1396 for (i
= disks
; i
--; ) {
1397 struct r5dev
*dev
= &sh
->dev
[i
];
1400 if (test_and_clear_bit(R5_Wantdrain
, &dev
->flags
)) {
1403 spin_lock_irq(&sh
->stripe_lock
);
1404 chosen
= dev
->towrite
;
1405 dev
->towrite
= NULL
;
1406 BUG_ON(dev
->written
);
1407 wbi
= dev
->written
= chosen
;
1408 spin_unlock_irq(&sh
->stripe_lock
);
1409 WARN_ON(dev
->page
!= dev
->orig_page
);
1411 while (wbi
&& wbi
->bi_iter
.bi_sector
<
1412 dev
->sector
+ STRIPE_SECTORS
) {
1413 if (wbi
->bi_rw
& REQ_FUA
)
1414 set_bit(R5_WantFUA
, &dev
->flags
);
1415 if (wbi
->bi_rw
& REQ_SYNC
)
1416 set_bit(R5_SyncIO
, &dev
->flags
);
1417 if (wbi
->bi_rw
& REQ_DISCARD
)
1418 set_bit(R5_Discard
, &dev
->flags
);
1420 tx
= async_copy_data(1, wbi
, &dev
->page
,
1421 dev
->sector
, tx
, sh
);
1422 if (dev
->page
!= dev
->orig_page
) {
1423 set_bit(R5_SkipCopy
, &dev
->flags
);
1424 clear_bit(R5_UPTODATE
, &dev
->flags
);
1425 clear_bit(R5_OVERWRITE
, &dev
->flags
);
1428 wbi
= r5_next_bio(wbi
, dev
->sector
);
1436 static void ops_complete_reconstruct(void *stripe_head_ref
)
1438 struct stripe_head
*sh
= stripe_head_ref
;
1439 int disks
= sh
->disks
;
1440 int pd_idx
= sh
->pd_idx
;
1441 int qd_idx
= sh
->qd_idx
;
1443 bool fua
= false, sync
= false, discard
= false;
1445 pr_debug("%s: stripe %llu\n", __func__
,
1446 (unsigned long long)sh
->sector
);
1448 for (i
= disks
; i
--; ) {
1449 fua
|= test_bit(R5_WantFUA
, &sh
->dev
[i
].flags
);
1450 sync
|= test_bit(R5_SyncIO
, &sh
->dev
[i
].flags
);
1451 discard
|= test_bit(R5_Discard
, &sh
->dev
[i
].flags
);
1454 for (i
= disks
; i
--; ) {
1455 struct r5dev
*dev
= &sh
->dev
[i
];
1457 if (dev
->written
|| i
== pd_idx
|| i
== qd_idx
) {
1458 if (!discard
&& !test_bit(R5_SkipCopy
, &dev
->flags
))
1459 set_bit(R5_UPTODATE
, &dev
->flags
);
1461 set_bit(R5_WantFUA
, &dev
->flags
);
1463 set_bit(R5_SyncIO
, &dev
->flags
);
1467 if (sh
->reconstruct_state
== reconstruct_state_drain_run
)
1468 sh
->reconstruct_state
= reconstruct_state_drain_result
;
1469 else if (sh
->reconstruct_state
== reconstruct_state_prexor_drain_run
)
1470 sh
->reconstruct_state
= reconstruct_state_prexor_drain_result
;
1472 BUG_ON(sh
->reconstruct_state
!= reconstruct_state_run
);
1473 sh
->reconstruct_state
= reconstruct_state_result
;
1476 set_bit(STRIPE_HANDLE
, &sh
->state
);
1481 ops_run_reconstruct5(struct stripe_head
*sh
, struct raid5_percpu
*percpu
,
1482 struct dma_async_tx_descriptor
*tx
)
1484 int disks
= sh
->disks
;
1485 struct page
**xor_srcs
= percpu
->scribble
;
1486 struct async_submit_ctl submit
;
1487 int count
= 0, pd_idx
= sh
->pd_idx
, i
;
1488 struct page
*xor_dest
;
1490 unsigned long flags
;
1492 pr_debug("%s: stripe %llu\n", __func__
,
1493 (unsigned long long)sh
->sector
);
1495 for (i
= 0; i
< sh
->disks
; i
++) {
1498 if (!test_bit(R5_Discard
, &sh
->dev
[i
].flags
))
1501 if (i
>= sh
->disks
) {
1502 atomic_inc(&sh
->count
);
1503 set_bit(R5_Discard
, &sh
->dev
[pd_idx
].flags
);
1504 ops_complete_reconstruct(sh
);
1507 /* check if prexor is active which means only process blocks
1508 * that are part of a read-modify-write (written)
1510 if (sh
->reconstruct_state
== reconstruct_state_prexor_drain_run
) {
1512 xor_dest
= xor_srcs
[count
++] = sh
->dev
[pd_idx
].page
;
1513 for (i
= disks
; i
--; ) {
1514 struct r5dev
*dev
= &sh
->dev
[i
];
1516 xor_srcs
[count
++] = dev
->page
;
1519 xor_dest
= sh
->dev
[pd_idx
].page
;
1520 for (i
= disks
; i
--; ) {
1521 struct r5dev
*dev
= &sh
->dev
[i
];
1523 xor_srcs
[count
++] = dev
->page
;
1527 /* 1/ if we prexor'd then the dest is reused as a source
1528 * 2/ if we did not prexor then we are redoing the parity
1529 * set ASYNC_TX_XOR_DROP_DST and ASYNC_TX_XOR_ZERO_DST
1530 * for the synchronous xor case
1532 flags
= ASYNC_TX_ACK
|
1533 (prexor
? ASYNC_TX_XOR_DROP_DST
: ASYNC_TX_XOR_ZERO_DST
);
1535 atomic_inc(&sh
->count
);
1537 init_async_submit(&submit
, flags
, tx
, ops_complete_reconstruct
, sh
,
1538 to_addr_conv(sh
, percpu
));
1539 if (unlikely(count
== 1))
1540 tx
= async_memcpy(xor_dest
, xor_srcs
[0], 0, 0, STRIPE_SIZE
, &submit
);
1542 tx
= async_xor(xor_dest
, xor_srcs
, 0, count
, STRIPE_SIZE
, &submit
);
1546 ops_run_reconstruct6(struct stripe_head
*sh
, struct raid5_percpu
*percpu
,
1547 struct dma_async_tx_descriptor
*tx
)
1549 struct async_submit_ctl submit
;
1550 struct page
**blocks
= percpu
->scribble
;
1553 pr_debug("%s: stripe %llu\n", __func__
, (unsigned long long)sh
->sector
);
1555 for (i
= 0; i
< sh
->disks
; i
++) {
1556 if (sh
->pd_idx
== i
|| sh
->qd_idx
== i
)
1558 if (!test_bit(R5_Discard
, &sh
->dev
[i
].flags
))
1561 if (i
>= sh
->disks
) {
1562 atomic_inc(&sh
->count
);
1563 set_bit(R5_Discard
, &sh
->dev
[sh
->pd_idx
].flags
);
1564 set_bit(R5_Discard
, &sh
->dev
[sh
->qd_idx
].flags
);
1565 ops_complete_reconstruct(sh
);
1569 count
= set_syndrome_sources(blocks
, sh
);
1571 atomic_inc(&sh
->count
);
1573 init_async_submit(&submit
, ASYNC_TX_ACK
, tx
, ops_complete_reconstruct
,
1574 sh
, to_addr_conv(sh
, percpu
));
1575 async_gen_syndrome(blocks
, 0, count
+2, STRIPE_SIZE
, &submit
);
1578 static void ops_complete_check(void *stripe_head_ref
)
1580 struct stripe_head
*sh
= stripe_head_ref
;
1582 pr_debug("%s: stripe %llu\n", __func__
,
1583 (unsigned long long)sh
->sector
);
1585 sh
->check_state
= check_state_check_result
;
1586 set_bit(STRIPE_HANDLE
, &sh
->state
);
1590 static void ops_run_check_p(struct stripe_head
*sh
, struct raid5_percpu
*percpu
)
1592 int disks
= sh
->disks
;
1593 int pd_idx
= sh
->pd_idx
;
1594 int qd_idx
= sh
->qd_idx
;
1595 struct page
*xor_dest
;
1596 struct page
**xor_srcs
= percpu
->scribble
;
1597 struct dma_async_tx_descriptor
*tx
;
1598 struct async_submit_ctl submit
;
1602 pr_debug("%s: stripe %llu\n", __func__
,
1603 (unsigned long long)sh
->sector
);
1606 xor_dest
= sh
->dev
[pd_idx
].page
;
1607 xor_srcs
[count
++] = xor_dest
;
1608 for (i
= disks
; i
--; ) {
1609 if (i
== pd_idx
|| i
== qd_idx
)
1611 xor_srcs
[count
++] = sh
->dev
[i
].page
;
1614 init_async_submit(&submit
, 0, NULL
, NULL
, NULL
,
1615 to_addr_conv(sh
, percpu
));
1616 tx
= async_xor_val(xor_dest
, xor_srcs
, 0, count
, STRIPE_SIZE
,
1617 &sh
->ops
.zero_sum_result
, &submit
);
1619 atomic_inc(&sh
->count
);
1620 init_async_submit(&submit
, ASYNC_TX_ACK
, tx
, ops_complete_check
, sh
, NULL
);
1621 tx
= async_trigger_callback(&submit
);
1624 static void ops_run_check_pq(struct stripe_head
*sh
, struct raid5_percpu
*percpu
, int checkp
)
1626 struct page
**srcs
= percpu
->scribble
;
1627 struct async_submit_ctl submit
;
1630 pr_debug("%s: stripe %llu checkp: %d\n", __func__
,
1631 (unsigned long long)sh
->sector
, checkp
);
1633 count
= set_syndrome_sources(srcs
, sh
);
1637 atomic_inc(&sh
->count
);
1638 init_async_submit(&submit
, ASYNC_TX_ACK
, NULL
, ops_complete_check
,
1639 sh
, to_addr_conv(sh
, percpu
));
1640 async_syndrome_val(srcs
, 0, count
+2, STRIPE_SIZE
,
1641 &sh
->ops
.zero_sum_result
, percpu
->spare_page
, &submit
);
1644 static void raid_run_ops(struct stripe_head
*sh
, unsigned long ops_request
)
1646 int overlap_clear
= 0, i
, disks
= sh
->disks
;
1647 struct dma_async_tx_descriptor
*tx
= NULL
;
1648 struct r5conf
*conf
= sh
->raid_conf
;
1649 int level
= conf
->level
;
1650 struct raid5_percpu
*percpu
;
1654 percpu
= per_cpu_ptr(conf
->percpu
, cpu
);
1655 if (test_bit(STRIPE_OP_BIOFILL
, &ops_request
)) {
1656 ops_run_biofill(sh
);
1660 if (test_bit(STRIPE_OP_COMPUTE_BLK
, &ops_request
)) {
1662 tx
= ops_run_compute5(sh
, percpu
);
1664 if (sh
->ops
.target2
< 0 || sh
->ops
.target
< 0)
1665 tx
= ops_run_compute6_1(sh
, percpu
);
1667 tx
= ops_run_compute6_2(sh
, percpu
);
1669 /* terminate the chain if reconstruct is not set to be run */
1670 if (tx
&& !test_bit(STRIPE_OP_RECONSTRUCT
, &ops_request
))
1674 if (test_bit(STRIPE_OP_PREXOR
, &ops_request
))
1675 tx
= ops_run_prexor(sh
, percpu
, tx
);
1677 if (test_bit(STRIPE_OP_BIODRAIN
, &ops_request
)) {
1678 tx
= ops_run_biodrain(sh
, tx
);
1682 if (test_bit(STRIPE_OP_RECONSTRUCT
, &ops_request
)) {
1684 ops_run_reconstruct5(sh
, percpu
, tx
);
1686 ops_run_reconstruct6(sh
, percpu
, tx
);
1689 if (test_bit(STRIPE_OP_CHECK
, &ops_request
)) {
1690 if (sh
->check_state
== check_state_run
)
1691 ops_run_check_p(sh
, percpu
);
1692 else if (sh
->check_state
== check_state_run_q
)
1693 ops_run_check_pq(sh
, percpu
, 0);
1694 else if (sh
->check_state
== check_state_run_pq
)
1695 ops_run_check_pq(sh
, percpu
, 1);
1701 for (i
= disks
; i
--; ) {
1702 struct r5dev
*dev
= &sh
->dev
[i
];
1703 if (test_and_clear_bit(R5_Overlap
, &dev
->flags
))
1704 wake_up(&sh
->raid_conf
->wait_for_overlap
);
1709 static int grow_one_stripe(struct r5conf
*conf
, int hash
)
1711 struct stripe_head
*sh
;
1712 sh
= kmem_cache_zalloc(conf
->slab_cache
, GFP_KERNEL
);
1716 sh
->raid_conf
= conf
;
1718 spin_lock_init(&sh
->stripe_lock
);
1720 if (grow_buffers(sh
)) {
1722 kmem_cache_free(conf
->slab_cache
, sh
);
1725 sh
->hash_lock_index
= hash
;
1726 /* we just created an active stripe so... */
1727 atomic_set(&sh
->count
, 1);
1728 atomic_inc(&conf
->active_stripes
);
1729 INIT_LIST_HEAD(&sh
->lru
);
1734 static int grow_stripes(struct r5conf
*conf
, int num
)
1736 struct kmem_cache
*sc
;
1737 int devs
= max(conf
->raid_disks
, conf
->previous_raid_disks
);
1740 if (conf
->mddev
->gendisk
)
1741 sprintf(conf
->cache_name
[0],
1742 "raid%d-%s", conf
->level
, mdname(conf
->mddev
));
1744 sprintf(conf
->cache_name
[0],
1745 "raid%d-%p", conf
->level
, conf
->mddev
);
1746 sprintf(conf
->cache_name
[1], "%s-alt", conf
->cache_name
[0]);
1748 conf
->active_name
= 0;
1749 sc
= kmem_cache_create(conf
->cache_name
[conf
->active_name
],
1750 sizeof(struct stripe_head
)+(devs
-1)*sizeof(struct r5dev
),
1754 conf
->slab_cache
= sc
;
1755 conf
->pool_size
= devs
;
1756 hash
= conf
->max_nr_stripes
% NR_STRIPE_HASH_LOCKS
;
1758 if (!grow_one_stripe(conf
, hash
))
1760 conf
->max_nr_stripes
++;
1761 hash
= (hash
+ 1) % NR_STRIPE_HASH_LOCKS
;
1767 * scribble_len - return the required size of the scribble region
1768 * @num - total number of disks in the array
1770 * The size must be enough to contain:
1771 * 1/ a struct page pointer for each device in the array +2
1772 * 2/ room to convert each entry in (1) to its corresponding dma
1773 * (dma_map_page()) or page (page_address()) address.
1775 * Note: the +2 is for the destination buffers of the ddf/raid6 case where we
1776 * calculate over all devices (not just the data blocks), using zeros in place
1777 * of the P and Q blocks.
1779 static size_t scribble_len(int num
)
1783 len
= sizeof(struct page
*) * (num
+2) + sizeof(addr_conv_t
) * (num
+2);
1788 static int resize_stripes(struct r5conf
*conf
, int newsize
)
1790 /* Make all the stripes able to hold 'newsize' devices.
1791 * New slots in each stripe get 'page' set to a new page.
1793 * This happens in stages:
1794 * 1/ create a new kmem_cache and allocate the required number of
1796 * 2/ gather all the old stripe_heads and transfer the pages across
1797 * to the new stripe_heads. This will have the side effect of
1798 * freezing the array as once all stripe_heads have been collected,
1799 * no IO will be possible. Old stripe heads are freed once their
1800 * pages have been transferred over, and the old kmem_cache is
1801 * freed when all stripes are done.
1802 * 3/ reallocate conf->disks to be suitable bigger. If this fails,
1803 * we simple return a failre status - no need to clean anything up.
1804 * 4/ allocate new pages for the new slots in the new stripe_heads.
1805 * If this fails, we don't bother trying the shrink the
1806 * stripe_heads down again, we just leave them as they are.
1807 * As each stripe_head is processed the new one is released into
1810 * Once step2 is started, we cannot afford to wait for a write,
1811 * so we use GFP_NOIO allocations.
1813 struct stripe_head
*osh
, *nsh
;
1814 LIST_HEAD(newstripes
);
1815 struct disk_info
*ndisks
;
1818 struct kmem_cache
*sc
;
1822 if (newsize
<= conf
->pool_size
)
1823 return 0; /* never bother to shrink */
1825 err
= md_allow_write(conf
->mddev
);
1830 sc
= kmem_cache_create(conf
->cache_name
[1-conf
->active_name
],
1831 sizeof(struct stripe_head
)+(newsize
-1)*sizeof(struct r5dev
),
1836 for (i
= conf
->max_nr_stripes
; i
; i
--) {
1837 nsh
= kmem_cache_zalloc(sc
, GFP_KERNEL
);
1841 nsh
->raid_conf
= conf
;
1842 spin_lock_init(&nsh
->stripe_lock
);
1844 list_add(&nsh
->lru
, &newstripes
);
1847 /* didn't get enough, give up */
1848 while (!list_empty(&newstripes
)) {
1849 nsh
= list_entry(newstripes
.next
, struct stripe_head
, lru
);
1850 list_del(&nsh
->lru
);
1851 kmem_cache_free(sc
, nsh
);
1853 kmem_cache_destroy(sc
);
1856 /* Step 2 - Must use GFP_NOIO now.
1857 * OK, we have enough stripes, start collecting inactive
1858 * stripes and copying them over
1862 list_for_each_entry(nsh
, &newstripes
, lru
) {
1863 lock_device_hash_lock(conf
, hash
);
1864 wait_event_cmd(conf
->wait_for_stripe
,
1865 !list_empty(conf
->inactive_list
+ hash
),
1866 unlock_device_hash_lock(conf
, hash
),
1867 lock_device_hash_lock(conf
, hash
));
1868 osh
= get_free_stripe(conf
, hash
);
1869 unlock_device_hash_lock(conf
, hash
);
1870 atomic_set(&nsh
->count
, 1);
1871 for(i
=0; i
<conf
->pool_size
; i
++) {
1872 nsh
->dev
[i
].page
= osh
->dev
[i
].page
;
1873 nsh
->dev
[i
].orig_page
= osh
->dev
[i
].page
;
1875 for( ; i
<newsize
; i
++)
1876 nsh
->dev
[i
].page
= NULL
;
1877 nsh
->hash_lock_index
= hash
;
1878 kmem_cache_free(conf
->slab_cache
, osh
);
1880 if (cnt
>= conf
->max_nr_stripes
/ NR_STRIPE_HASH_LOCKS
+
1881 !!((conf
->max_nr_stripes
% NR_STRIPE_HASH_LOCKS
) > hash
)) {
1886 kmem_cache_destroy(conf
->slab_cache
);
1889 * At this point, we are holding all the stripes so the array
1890 * is completely stalled, so now is a good time to resize
1891 * conf->disks and the scribble region
1893 ndisks
= kzalloc(newsize
* sizeof(struct disk_info
), GFP_NOIO
);
1895 for (i
=0; i
<conf
->raid_disks
; i
++)
1896 ndisks
[i
] = conf
->disks
[i
];
1898 conf
->disks
= ndisks
;
1903 conf
->scribble_len
= scribble_len(newsize
);
1904 for_each_present_cpu(cpu
) {
1905 struct raid5_percpu
*percpu
;
1908 percpu
= per_cpu_ptr(conf
->percpu
, cpu
);
1909 scribble
= kmalloc(conf
->scribble_len
, GFP_NOIO
);
1912 kfree(percpu
->scribble
);
1913 percpu
->scribble
= scribble
;
1921 /* Step 4, return new stripes to service */
1922 while(!list_empty(&newstripes
)) {
1923 nsh
= list_entry(newstripes
.next
, struct stripe_head
, lru
);
1924 list_del_init(&nsh
->lru
);
1926 for (i
=conf
->raid_disks
; i
< newsize
; i
++)
1927 if (nsh
->dev
[i
].page
== NULL
) {
1928 struct page
*p
= alloc_page(GFP_NOIO
);
1929 nsh
->dev
[i
].page
= p
;
1930 nsh
->dev
[i
].orig_page
= p
;
1934 release_stripe(nsh
);
1936 /* critical section pass, GFP_NOIO no longer needed */
1938 conf
->slab_cache
= sc
;
1939 conf
->active_name
= 1-conf
->active_name
;
1940 conf
->pool_size
= newsize
;
1944 static int drop_one_stripe(struct r5conf
*conf
, int hash
)
1946 struct stripe_head
*sh
;
1948 spin_lock_irq(conf
->hash_locks
+ hash
);
1949 sh
= get_free_stripe(conf
, hash
);
1950 spin_unlock_irq(conf
->hash_locks
+ hash
);
1953 BUG_ON(atomic_read(&sh
->count
));
1955 kmem_cache_free(conf
->slab_cache
, sh
);
1956 atomic_dec(&conf
->active_stripes
);
1960 static void shrink_stripes(struct r5conf
*conf
)
1963 for (hash
= 0; hash
< NR_STRIPE_HASH_LOCKS
; hash
++)
1964 while (drop_one_stripe(conf
, hash
))
1967 if (conf
->slab_cache
)
1968 kmem_cache_destroy(conf
->slab_cache
);
1969 conf
->slab_cache
= NULL
;
1972 static void raid5_end_read_request(struct bio
* bi
, int error
)
1974 struct stripe_head
*sh
= bi
->bi_private
;
1975 struct r5conf
*conf
= sh
->raid_conf
;
1976 int disks
= sh
->disks
, i
;
1977 int uptodate
= test_bit(BIO_UPTODATE
, &bi
->bi_flags
);
1978 char b
[BDEVNAME_SIZE
];
1979 struct md_rdev
*rdev
= NULL
;
1982 for (i
=0 ; i
<disks
; i
++)
1983 if (bi
== &sh
->dev
[i
].req
)
1986 pr_debug("end_read_request %llu/%d, count: %d, uptodate %d.\n",
1987 (unsigned long long)sh
->sector
, i
, atomic_read(&sh
->count
),
1993 if (test_bit(R5_ReadRepl
, &sh
->dev
[i
].flags
))
1994 /* If replacement finished while this request was outstanding,
1995 * 'replacement' might be NULL already.
1996 * In that case it moved down to 'rdev'.
1997 * rdev is not removed until all requests are finished.
1999 rdev
= conf
->disks
[i
].replacement
;
2001 rdev
= conf
->disks
[i
].rdev
;
2003 if (use_new_offset(conf
, sh
))
2004 s
= sh
->sector
+ rdev
->new_data_offset
;
2006 s
= sh
->sector
+ rdev
->data_offset
;
2008 set_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
);
2009 if (test_bit(R5_ReadError
, &sh
->dev
[i
].flags
)) {
2010 /* Note that this cannot happen on a
2011 * replacement device. We just fail those on
2016 "md/raid:%s: read error corrected"
2017 " (%lu sectors at %llu on %s)\n",
2018 mdname(conf
->mddev
), STRIPE_SECTORS
,
2019 (unsigned long long)s
,
2020 bdevname(rdev
->bdev
, b
));
2021 atomic_add(STRIPE_SECTORS
, &rdev
->corrected_errors
);
2022 clear_bit(R5_ReadError
, &sh
->dev
[i
].flags
);
2023 clear_bit(R5_ReWrite
, &sh
->dev
[i
].flags
);
2024 } else if (test_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
))
2025 clear_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
);
2027 if (atomic_read(&rdev
->read_errors
))
2028 atomic_set(&rdev
->read_errors
, 0);
2030 const char *bdn
= bdevname(rdev
->bdev
, b
);
2034 clear_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
);
2035 atomic_inc(&rdev
->read_errors
);
2036 if (test_bit(R5_ReadRepl
, &sh
->dev
[i
].flags
))
2039 "md/raid:%s: read error on replacement device "
2040 "(sector %llu on %s).\n",
2041 mdname(conf
->mddev
),
2042 (unsigned long long)s
,
2044 else if (conf
->mddev
->degraded
>= conf
->max_degraded
) {
2048 "md/raid:%s: read error not correctable "
2049 "(sector %llu on %s).\n",
2050 mdname(conf
->mddev
),
2051 (unsigned long long)s
,
2053 } else if (test_bit(R5_ReWrite
, &sh
->dev
[i
].flags
)) {
2058 "md/raid:%s: read error NOT corrected!! "
2059 "(sector %llu on %s).\n",
2060 mdname(conf
->mddev
),
2061 (unsigned long long)s
,
2063 } else if (atomic_read(&rdev
->read_errors
)
2064 > conf
->max_nr_stripes
)
2066 "md/raid:%s: Too many read errors, failing device %s.\n",
2067 mdname(conf
->mddev
), bdn
);
2070 if (set_bad
&& test_bit(In_sync
, &rdev
->flags
)
2071 && !test_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
))
2074 if (test_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
)) {
2075 set_bit(R5_ReadError
, &sh
->dev
[i
].flags
);
2076 clear_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
);
2078 set_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
);
2080 clear_bit(R5_ReadError
, &sh
->dev
[i
].flags
);
2081 clear_bit(R5_ReWrite
, &sh
->dev
[i
].flags
);
2083 && test_bit(In_sync
, &rdev
->flags
)
2084 && rdev_set_badblocks(
2085 rdev
, sh
->sector
, STRIPE_SECTORS
, 0)))
2086 md_error(conf
->mddev
, rdev
);
2089 rdev_dec_pending(rdev
, conf
->mddev
);
2090 clear_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
2091 set_bit(STRIPE_HANDLE
, &sh
->state
);
2095 static void raid5_end_write_request(struct bio
*bi
, int error
)
2097 struct stripe_head
*sh
= bi
->bi_private
;
2098 struct r5conf
*conf
= sh
->raid_conf
;
2099 int disks
= sh
->disks
, i
;
2100 struct md_rdev
*uninitialized_var(rdev
);
2101 int uptodate
= test_bit(BIO_UPTODATE
, &bi
->bi_flags
);
2104 int replacement
= 0;
2106 for (i
= 0 ; i
< disks
; i
++) {
2107 if (bi
== &sh
->dev
[i
].req
) {
2108 rdev
= conf
->disks
[i
].rdev
;
2111 if (bi
== &sh
->dev
[i
].rreq
) {
2112 rdev
= conf
->disks
[i
].replacement
;
2116 /* rdev was removed and 'replacement'
2117 * replaced it. rdev is not removed
2118 * until all requests are finished.
2120 rdev
= conf
->disks
[i
].rdev
;
2124 pr_debug("end_write_request %llu/%d, count %d, uptodate: %d.\n",
2125 (unsigned long long)sh
->sector
, i
, atomic_read(&sh
->count
),
2134 md_error(conf
->mddev
, rdev
);
2135 else if (is_badblock(rdev
, sh
->sector
,
2137 &first_bad
, &bad_sectors
))
2138 set_bit(R5_MadeGoodRepl
, &sh
->dev
[i
].flags
);
2141 set_bit(STRIPE_DEGRADED
, &sh
->state
);
2142 set_bit(WriteErrorSeen
, &rdev
->flags
);
2143 set_bit(R5_WriteError
, &sh
->dev
[i
].flags
);
2144 if (!test_and_set_bit(WantReplacement
, &rdev
->flags
))
2145 set_bit(MD_RECOVERY_NEEDED
,
2146 &rdev
->mddev
->recovery
);
2147 } else if (is_badblock(rdev
, sh
->sector
,
2149 &first_bad
, &bad_sectors
)) {
2150 set_bit(R5_MadeGood
, &sh
->dev
[i
].flags
);
2151 if (test_bit(R5_ReadError
, &sh
->dev
[i
].flags
))
2152 /* That was a successful write so make
2153 * sure it looks like we already did
2156 set_bit(R5_ReWrite
, &sh
->dev
[i
].flags
);
2159 rdev_dec_pending(rdev
, conf
->mddev
);
2161 if (!test_and_clear_bit(R5_DOUBLE_LOCKED
, &sh
->dev
[i
].flags
))
2162 clear_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
2163 set_bit(STRIPE_HANDLE
, &sh
->state
);
2167 static sector_t
compute_blocknr(struct stripe_head
*sh
, int i
, int previous
);
2169 static void raid5_build_block(struct stripe_head
*sh
, int i
, int previous
)
2171 struct r5dev
*dev
= &sh
->dev
[i
];
2173 bio_init(&dev
->req
);
2174 dev
->req
.bi_io_vec
= &dev
->vec
;
2175 dev
->req
.bi_max_vecs
= 1;
2176 dev
->req
.bi_private
= sh
;
2178 bio_init(&dev
->rreq
);
2179 dev
->rreq
.bi_io_vec
= &dev
->rvec
;
2180 dev
->rreq
.bi_max_vecs
= 1;
2181 dev
->rreq
.bi_private
= sh
;
2184 dev
->sector
= compute_blocknr(sh
, i
, previous
);
2187 static void error(struct mddev
*mddev
, struct md_rdev
*rdev
)
2189 char b
[BDEVNAME_SIZE
];
2190 struct r5conf
*conf
= mddev
->private;
2191 unsigned long flags
;
2192 pr_debug("raid456: error called\n");
2194 spin_lock_irqsave(&conf
->device_lock
, flags
);
2195 clear_bit(In_sync
, &rdev
->flags
);
2196 mddev
->degraded
= calc_degraded(conf
);
2197 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
2198 set_bit(MD_RECOVERY_INTR
, &mddev
->recovery
);
2200 set_bit(Blocked
, &rdev
->flags
);
2201 set_bit(Faulty
, &rdev
->flags
);
2202 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
2204 "md/raid:%s: Disk failure on %s, disabling device.\n"
2205 "md/raid:%s: Operation continuing on %d devices.\n",
2207 bdevname(rdev
->bdev
, b
),
2209 conf
->raid_disks
- mddev
->degraded
);
2213 * Input: a 'big' sector number,
2214 * Output: index of the data and parity disk, and the sector # in them.
2216 static sector_t
raid5_compute_sector(struct r5conf
*conf
, sector_t r_sector
,
2217 int previous
, int *dd_idx
,
2218 struct stripe_head
*sh
)
2220 sector_t stripe
, stripe2
;
2221 sector_t chunk_number
;
2222 unsigned int chunk_offset
;
2225 sector_t new_sector
;
2226 int algorithm
= previous
? conf
->prev_algo
2228 int sectors_per_chunk
= previous
? conf
->prev_chunk_sectors
2229 : conf
->chunk_sectors
;
2230 int raid_disks
= previous
? conf
->previous_raid_disks
2232 int data_disks
= raid_disks
- conf
->max_degraded
;
2234 /* First compute the information on this sector */
2237 * Compute the chunk number and the sector offset inside the chunk
2239 chunk_offset
= sector_div(r_sector
, sectors_per_chunk
);
2240 chunk_number
= r_sector
;
2243 * Compute the stripe number
2245 stripe
= chunk_number
;
2246 *dd_idx
= sector_div(stripe
, data_disks
);
2249 * Select the parity disk based on the user selected algorithm.
2251 pd_idx
= qd_idx
= -1;
2252 switch(conf
->level
) {
2254 pd_idx
= data_disks
;
2257 switch (algorithm
) {
2258 case ALGORITHM_LEFT_ASYMMETRIC
:
2259 pd_idx
= data_disks
- sector_div(stripe2
, raid_disks
);
2260 if (*dd_idx
>= pd_idx
)
2263 case ALGORITHM_RIGHT_ASYMMETRIC
:
2264 pd_idx
= sector_div(stripe2
, raid_disks
);
2265 if (*dd_idx
>= pd_idx
)
2268 case ALGORITHM_LEFT_SYMMETRIC
:
2269 pd_idx
= data_disks
- sector_div(stripe2
, raid_disks
);
2270 *dd_idx
= (pd_idx
+ 1 + *dd_idx
) % raid_disks
;
2272 case ALGORITHM_RIGHT_SYMMETRIC
:
2273 pd_idx
= sector_div(stripe2
, raid_disks
);
2274 *dd_idx
= (pd_idx
+ 1 + *dd_idx
) % raid_disks
;
2276 case ALGORITHM_PARITY_0
:
2280 case ALGORITHM_PARITY_N
:
2281 pd_idx
= data_disks
;
2289 switch (algorithm
) {
2290 case ALGORITHM_LEFT_ASYMMETRIC
:
2291 pd_idx
= raid_disks
- 1 - sector_div(stripe2
, raid_disks
);
2292 qd_idx
= pd_idx
+ 1;
2293 if (pd_idx
== raid_disks
-1) {
2294 (*dd_idx
)++; /* Q D D D P */
2296 } else if (*dd_idx
>= pd_idx
)
2297 (*dd_idx
) += 2; /* D D P Q D */
2299 case ALGORITHM_RIGHT_ASYMMETRIC
:
2300 pd_idx
= sector_div(stripe2
, raid_disks
);
2301 qd_idx
= pd_idx
+ 1;
2302 if (pd_idx
== raid_disks
-1) {
2303 (*dd_idx
)++; /* Q D D D P */
2305 } else if (*dd_idx
>= pd_idx
)
2306 (*dd_idx
) += 2; /* D D P Q D */
2308 case ALGORITHM_LEFT_SYMMETRIC
:
2309 pd_idx
= raid_disks
- 1 - sector_div(stripe2
, raid_disks
);
2310 qd_idx
= (pd_idx
+ 1) % raid_disks
;
2311 *dd_idx
= (pd_idx
+ 2 + *dd_idx
) % raid_disks
;
2313 case ALGORITHM_RIGHT_SYMMETRIC
:
2314 pd_idx
= sector_div(stripe2
, raid_disks
);
2315 qd_idx
= (pd_idx
+ 1) % raid_disks
;
2316 *dd_idx
= (pd_idx
+ 2 + *dd_idx
) % raid_disks
;
2319 case ALGORITHM_PARITY_0
:
2324 case ALGORITHM_PARITY_N
:
2325 pd_idx
= data_disks
;
2326 qd_idx
= data_disks
+ 1;
2329 case ALGORITHM_ROTATING_ZERO_RESTART
:
2330 /* Exactly the same as RIGHT_ASYMMETRIC, but or
2331 * of blocks for computing Q is different.
2333 pd_idx
= sector_div(stripe2
, raid_disks
);
2334 qd_idx
= pd_idx
+ 1;
2335 if (pd_idx
== raid_disks
-1) {
2336 (*dd_idx
)++; /* Q D D D P */
2338 } else if (*dd_idx
>= pd_idx
)
2339 (*dd_idx
) += 2; /* D D P Q D */
2343 case ALGORITHM_ROTATING_N_RESTART
:
2344 /* Same a left_asymmetric, by first stripe is
2345 * D D D P Q rather than
2349 pd_idx
= raid_disks
- 1 - sector_div(stripe2
, raid_disks
);
2350 qd_idx
= pd_idx
+ 1;
2351 if (pd_idx
== raid_disks
-1) {
2352 (*dd_idx
)++; /* Q D D D P */
2354 } else if (*dd_idx
>= pd_idx
)
2355 (*dd_idx
) += 2; /* D D P Q D */
2359 case ALGORITHM_ROTATING_N_CONTINUE
:
2360 /* Same as left_symmetric but Q is before P */
2361 pd_idx
= raid_disks
- 1 - sector_div(stripe2
, raid_disks
);
2362 qd_idx
= (pd_idx
+ raid_disks
- 1) % raid_disks
;
2363 *dd_idx
= (pd_idx
+ 1 + *dd_idx
) % raid_disks
;
2367 case ALGORITHM_LEFT_ASYMMETRIC_6
:
2368 /* RAID5 left_asymmetric, with Q on last device */
2369 pd_idx
= data_disks
- sector_div(stripe2
, raid_disks
-1);
2370 if (*dd_idx
>= pd_idx
)
2372 qd_idx
= raid_disks
- 1;
2375 case ALGORITHM_RIGHT_ASYMMETRIC_6
:
2376 pd_idx
= sector_div(stripe2
, raid_disks
-1);
2377 if (*dd_idx
>= pd_idx
)
2379 qd_idx
= raid_disks
- 1;
2382 case ALGORITHM_LEFT_SYMMETRIC_6
:
2383 pd_idx
= data_disks
- sector_div(stripe2
, raid_disks
-1);
2384 *dd_idx
= (pd_idx
+ 1 + *dd_idx
) % (raid_disks
-1);
2385 qd_idx
= raid_disks
- 1;
2388 case ALGORITHM_RIGHT_SYMMETRIC_6
:
2389 pd_idx
= sector_div(stripe2
, raid_disks
-1);
2390 *dd_idx
= (pd_idx
+ 1 + *dd_idx
) % (raid_disks
-1);
2391 qd_idx
= raid_disks
- 1;
2394 case ALGORITHM_PARITY_0_6
:
2397 qd_idx
= raid_disks
- 1;
2407 sh
->pd_idx
= pd_idx
;
2408 sh
->qd_idx
= qd_idx
;
2409 sh
->ddf_layout
= ddf_layout
;
2412 * Finally, compute the new sector number
2414 new_sector
= (sector_t
)stripe
* sectors_per_chunk
+ chunk_offset
;
2419 static sector_t
compute_blocknr(struct stripe_head
*sh
, int i
, int previous
)
2421 struct r5conf
*conf
= sh
->raid_conf
;
2422 int raid_disks
= sh
->disks
;
2423 int data_disks
= raid_disks
- conf
->max_degraded
;
2424 sector_t new_sector
= sh
->sector
, check
;
2425 int sectors_per_chunk
= previous
? conf
->prev_chunk_sectors
2426 : conf
->chunk_sectors
;
2427 int algorithm
= previous
? conf
->prev_algo
2431 sector_t chunk_number
;
2432 int dummy1
, dd_idx
= i
;
2434 struct stripe_head sh2
;
2437 chunk_offset
= sector_div(new_sector
, sectors_per_chunk
);
2438 stripe
= new_sector
;
2440 if (i
== sh
->pd_idx
)
2442 switch(conf
->level
) {
2445 switch (algorithm
) {
2446 case ALGORITHM_LEFT_ASYMMETRIC
:
2447 case ALGORITHM_RIGHT_ASYMMETRIC
:
2451 case ALGORITHM_LEFT_SYMMETRIC
:
2452 case ALGORITHM_RIGHT_SYMMETRIC
:
2455 i
-= (sh
->pd_idx
+ 1);
2457 case ALGORITHM_PARITY_0
:
2460 case ALGORITHM_PARITY_N
:
2467 if (i
== sh
->qd_idx
)
2468 return 0; /* It is the Q disk */
2469 switch (algorithm
) {
2470 case ALGORITHM_LEFT_ASYMMETRIC
:
2471 case ALGORITHM_RIGHT_ASYMMETRIC
:
2472 case ALGORITHM_ROTATING_ZERO_RESTART
:
2473 case ALGORITHM_ROTATING_N_RESTART
:
2474 if (sh
->pd_idx
== raid_disks
-1)
2475 i
--; /* Q D D D P */
2476 else if (i
> sh
->pd_idx
)
2477 i
-= 2; /* D D P Q D */
2479 case ALGORITHM_LEFT_SYMMETRIC
:
2480 case ALGORITHM_RIGHT_SYMMETRIC
:
2481 if (sh
->pd_idx
== raid_disks
-1)
2482 i
--; /* Q D D D P */
2487 i
-= (sh
->pd_idx
+ 2);
2490 case ALGORITHM_PARITY_0
:
2493 case ALGORITHM_PARITY_N
:
2495 case ALGORITHM_ROTATING_N_CONTINUE
:
2496 /* Like left_symmetric, but P is before Q */
2497 if (sh
->pd_idx
== 0)
2498 i
--; /* P D D D Q */
2503 i
-= (sh
->pd_idx
+ 1);
2506 case ALGORITHM_LEFT_ASYMMETRIC_6
:
2507 case ALGORITHM_RIGHT_ASYMMETRIC_6
:
2511 case ALGORITHM_LEFT_SYMMETRIC_6
:
2512 case ALGORITHM_RIGHT_SYMMETRIC_6
:
2514 i
+= data_disks
+ 1;
2515 i
-= (sh
->pd_idx
+ 1);
2517 case ALGORITHM_PARITY_0_6
:
2526 chunk_number
= stripe
* data_disks
+ i
;
2527 r_sector
= chunk_number
* sectors_per_chunk
+ chunk_offset
;
2529 check
= raid5_compute_sector(conf
, r_sector
,
2530 previous
, &dummy1
, &sh2
);
2531 if (check
!= sh
->sector
|| dummy1
!= dd_idx
|| sh2
.pd_idx
!= sh
->pd_idx
2532 || sh2
.qd_idx
!= sh
->qd_idx
) {
2533 printk(KERN_ERR
"md/raid:%s: compute_blocknr: map not correct\n",
2534 mdname(conf
->mddev
));
2542 schedule_reconstruction(struct stripe_head
*sh
, struct stripe_head_state
*s
,
2543 int rcw
, int expand
)
2545 int i
, pd_idx
= sh
->pd_idx
, disks
= sh
->disks
;
2546 struct r5conf
*conf
= sh
->raid_conf
;
2547 int level
= conf
->level
;
2551 for (i
= disks
; i
--; ) {
2552 struct r5dev
*dev
= &sh
->dev
[i
];
2555 set_bit(R5_LOCKED
, &dev
->flags
);
2556 set_bit(R5_Wantdrain
, &dev
->flags
);
2558 clear_bit(R5_UPTODATE
, &dev
->flags
);
2562 /* if we are not expanding this is a proper write request, and
2563 * there will be bios with new data to be drained into the
2568 /* False alarm, nothing to do */
2570 sh
->reconstruct_state
= reconstruct_state_drain_run
;
2571 set_bit(STRIPE_OP_BIODRAIN
, &s
->ops_request
);
2573 sh
->reconstruct_state
= reconstruct_state_run
;
2575 set_bit(STRIPE_OP_RECONSTRUCT
, &s
->ops_request
);
2577 if (s
->locked
+ conf
->max_degraded
== disks
)
2578 if (!test_and_set_bit(STRIPE_FULL_WRITE
, &sh
->state
))
2579 atomic_inc(&conf
->pending_full_writes
);
2582 BUG_ON(!(test_bit(R5_UPTODATE
, &sh
->dev
[pd_idx
].flags
) ||
2583 test_bit(R5_Wantcompute
, &sh
->dev
[pd_idx
].flags
)));
2585 for (i
= disks
; i
--; ) {
2586 struct r5dev
*dev
= &sh
->dev
[i
];
2591 (test_bit(R5_UPTODATE
, &dev
->flags
) ||
2592 test_bit(R5_Wantcompute
, &dev
->flags
))) {
2593 set_bit(R5_Wantdrain
, &dev
->flags
);
2594 set_bit(R5_LOCKED
, &dev
->flags
);
2595 clear_bit(R5_UPTODATE
, &dev
->flags
);
2600 /* False alarm - nothing to do */
2602 sh
->reconstruct_state
= reconstruct_state_prexor_drain_run
;
2603 set_bit(STRIPE_OP_PREXOR
, &s
->ops_request
);
2604 set_bit(STRIPE_OP_BIODRAIN
, &s
->ops_request
);
2605 set_bit(STRIPE_OP_RECONSTRUCT
, &s
->ops_request
);
2608 /* keep the parity disk(s) locked while asynchronous operations
2611 set_bit(R5_LOCKED
, &sh
->dev
[pd_idx
].flags
);
2612 clear_bit(R5_UPTODATE
, &sh
->dev
[pd_idx
].flags
);
2616 int qd_idx
= sh
->qd_idx
;
2617 struct r5dev
*dev
= &sh
->dev
[qd_idx
];
2619 set_bit(R5_LOCKED
, &dev
->flags
);
2620 clear_bit(R5_UPTODATE
, &dev
->flags
);
2624 pr_debug("%s: stripe %llu locked: %d ops_request: %lx\n",
2625 __func__
, (unsigned long long)sh
->sector
,
2626 s
->locked
, s
->ops_request
);
2630 * Each stripe/dev can have one or more bion attached.
2631 * toread/towrite point to the first in a chain.
2632 * The bi_next chain must be in order.
2634 static int add_stripe_bio(struct stripe_head
*sh
, struct bio
*bi
, int dd_idx
, int forwrite
)
2637 struct r5conf
*conf
= sh
->raid_conf
;
2640 pr_debug("adding bi b#%llu to stripe s#%llu\n",
2641 (unsigned long long)bi
->bi_iter
.bi_sector
,
2642 (unsigned long long)sh
->sector
);
2645 * If several bio share a stripe. The bio bi_phys_segments acts as a
2646 * reference count to avoid race. The reference count should already be
2647 * increased before this function is called (for example, in
2648 * make_request()), so other bio sharing this stripe will not free the
2649 * stripe. If a stripe is owned by one stripe, the stripe lock will
2652 spin_lock_irq(&sh
->stripe_lock
);
2654 bip
= &sh
->dev
[dd_idx
].towrite
;
2658 bip
= &sh
->dev
[dd_idx
].toread
;
2659 while (*bip
&& (*bip
)->bi_iter
.bi_sector
< bi
->bi_iter
.bi_sector
) {
2660 if (bio_end_sector(*bip
) > bi
->bi_iter
.bi_sector
)
2662 bip
= & (*bip
)->bi_next
;
2664 if (*bip
&& (*bip
)->bi_iter
.bi_sector
< bio_end_sector(bi
))
2667 BUG_ON(*bip
&& bi
->bi_next
&& (*bip
) != bi
->bi_next
);
2671 raid5_inc_bi_active_stripes(bi
);
2674 /* check if page is covered */
2675 sector_t sector
= sh
->dev
[dd_idx
].sector
;
2676 for (bi
=sh
->dev
[dd_idx
].towrite
;
2677 sector
< sh
->dev
[dd_idx
].sector
+ STRIPE_SECTORS
&&
2678 bi
&& bi
->bi_iter
.bi_sector
<= sector
;
2679 bi
= r5_next_bio(bi
, sh
->dev
[dd_idx
].sector
)) {
2680 if (bio_end_sector(bi
) >= sector
)
2681 sector
= bio_end_sector(bi
);
2683 if (sector
>= sh
->dev
[dd_idx
].sector
+ STRIPE_SECTORS
)
2684 set_bit(R5_OVERWRITE
, &sh
->dev
[dd_idx
].flags
);
2687 pr_debug("added bi b#%llu to stripe s#%llu, disk %d.\n",
2688 (unsigned long long)(*bip
)->bi_iter
.bi_sector
,
2689 (unsigned long long)sh
->sector
, dd_idx
);
2690 spin_unlock_irq(&sh
->stripe_lock
);
2692 if (conf
->mddev
->bitmap
&& firstwrite
) {
2693 bitmap_startwrite(conf
->mddev
->bitmap
, sh
->sector
,
2695 sh
->bm_seq
= conf
->seq_flush
+1;
2696 set_bit(STRIPE_BIT_DELAY
, &sh
->state
);
2701 set_bit(R5_Overlap
, &sh
->dev
[dd_idx
].flags
);
2702 spin_unlock_irq(&sh
->stripe_lock
);
2706 static void end_reshape(struct r5conf
*conf
);
2708 static void stripe_set_idx(sector_t stripe
, struct r5conf
*conf
, int previous
,
2709 struct stripe_head
*sh
)
2711 int sectors_per_chunk
=
2712 previous
? conf
->prev_chunk_sectors
: conf
->chunk_sectors
;
2714 int chunk_offset
= sector_div(stripe
, sectors_per_chunk
);
2715 int disks
= previous
? conf
->previous_raid_disks
: conf
->raid_disks
;
2717 raid5_compute_sector(conf
,
2718 stripe
* (disks
- conf
->max_degraded
)
2719 *sectors_per_chunk
+ chunk_offset
,
2725 handle_failed_stripe(struct r5conf
*conf
, struct stripe_head
*sh
,
2726 struct stripe_head_state
*s
, int disks
,
2727 struct bio
**return_bi
)
2730 for (i
= disks
; i
--; ) {
2734 if (test_bit(R5_ReadError
, &sh
->dev
[i
].flags
)) {
2735 struct md_rdev
*rdev
;
2737 rdev
= rcu_dereference(conf
->disks
[i
].rdev
);
2738 if (rdev
&& test_bit(In_sync
, &rdev
->flags
))
2739 atomic_inc(&rdev
->nr_pending
);
2744 if (!rdev_set_badblocks(
2748 md_error(conf
->mddev
, rdev
);
2749 rdev_dec_pending(rdev
, conf
->mddev
);
2752 spin_lock_irq(&sh
->stripe_lock
);
2753 /* fail all writes first */
2754 bi
= sh
->dev
[i
].towrite
;
2755 sh
->dev
[i
].towrite
= NULL
;
2756 spin_unlock_irq(&sh
->stripe_lock
);
2760 if (test_and_clear_bit(R5_Overlap
, &sh
->dev
[i
].flags
))
2761 wake_up(&conf
->wait_for_overlap
);
2763 while (bi
&& bi
->bi_iter
.bi_sector
<
2764 sh
->dev
[i
].sector
+ STRIPE_SECTORS
) {
2765 struct bio
*nextbi
= r5_next_bio(bi
, sh
->dev
[i
].sector
);
2766 clear_bit(BIO_UPTODATE
, &bi
->bi_flags
);
2767 if (!raid5_dec_bi_active_stripes(bi
)) {
2768 md_write_end(conf
->mddev
);
2769 bi
->bi_next
= *return_bi
;
2775 bitmap_endwrite(conf
->mddev
->bitmap
, sh
->sector
,
2776 STRIPE_SECTORS
, 0, 0);
2778 /* and fail all 'written' */
2779 bi
= sh
->dev
[i
].written
;
2780 sh
->dev
[i
].written
= NULL
;
2781 if (test_and_clear_bit(R5_SkipCopy
, &sh
->dev
[i
].flags
)) {
2782 WARN_ON(test_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
));
2783 sh
->dev
[i
].page
= sh
->dev
[i
].orig_page
;
2786 if (bi
) bitmap_end
= 1;
2787 while (bi
&& bi
->bi_iter
.bi_sector
<
2788 sh
->dev
[i
].sector
+ STRIPE_SECTORS
) {
2789 struct bio
*bi2
= r5_next_bio(bi
, sh
->dev
[i
].sector
);
2790 clear_bit(BIO_UPTODATE
, &bi
->bi_flags
);
2791 if (!raid5_dec_bi_active_stripes(bi
)) {
2792 md_write_end(conf
->mddev
);
2793 bi
->bi_next
= *return_bi
;
2799 /* fail any reads if this device is non-operational and
2800 * the data has not reached the cache yet.
2802 if (!test_bit(R5_Wantfill
, &sh
->dev
[i
].flags
) &&
2803 (!test_bit(R5_Insync
, &sh
->dev
[i
].flags
) ||
2804 test_bit(R5_ReadError
, &sh
->dev
[i
].flags
))) {
2805 spin_lock_irq(&sh
->stripe_lock
);
2806 bi
= sh
->dev
[i
].toread
;
2807 sh
->dev
[i
].toread
= NULL
;
2808 spin_unlock_irq(&sh
->stripe_lock
);
2809 if (test_and_clear_bit(R5_Overlap
, &sh
->dev
[i
].flags
))
2810 wake_up(&conf
->wait_for_overlap
);
2811 while (bi
&& bi
->bi_iter
.bi_sector
<
2812 sh
->dev
[i
].sector
+ STRIPE_SECTORS
) {
2813 struct bio
*nextbi
=
2814 r5_next_bio(bi
, sh
->dev
[i
].sector
);
2815 clear_bit(BIO_UPTODATE
, &bi
->bi_flags
);
2816 if (!raid5_dec_bi_active_stripes(bi
)) {
2817 bi
->bi_next
= *return_bi
;
2824 bitmap_endwrite(conf
->mddev
->bitmap
, sh
->sector
,
2825 STRIPE_SECTORS
, 0, 0);
2826 /* If we were in the middle of a write the parity block might
2827 * still be locked - so just clear all R5_LOCKED flags
2829 clear_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
2832 if (test_and_clear_bit(STRIPE_FULL_WRITE
, &sh
->state
))
2833 if (atomic_dec_and_test(&conf
->pending_full_writes
))
2834 md_wakeup_thread(conf
->mddev
->thread
);
2838 handle_failed_sync(struct r5conf
*conf
, struct stripe_head
*sh
,
2839 struct stripe_head_state
*s
)
2844 clear_bit(STRIPE_SYNCING
, &sh
->state
);
2845 if (test_and_clear_bit(R5_Overlap
, &sh
->dev
[sh
->pd_idx
].flags
))
2846 wake_up(&conf
->wait_for_overlap
);
2849 /* There is nothing more to do for sync/check/repair.
2850 * Don't even need to abort as that is handled elsewhere
2851 * if needed, and not always wanted e.g. if there is a known
2853 * For recover/replace we need to record a bad block on all
2854 * non-sync devices, or abort the recovery
2856 if (test_bit(MD_RECOVERY_RECOVER
, &conf
->mddev
->recovery
)) {
2857 /* During recovery devices cannot be removed, so
2858 * locking and refcounting of rdevs is not needed
2860 for (i
= 0; i
< conf
->raid_disks
; i
++) {
2861 struct md_rdev
*rdev
= conf
->disks
[i
].rdev
;
2863 && !test_bit(Faulty
, &rdev
->flags
)
2864 && !test_bit(In_sync
, &rdev
->flags
)
2865 && !rdev_set_badblocks(rdev
, sh
->sector
,
2868 rdev
= conf
->disks
[i
].replacement
;
2870 && !test_bit(Faulty
, &rdev
->flags
)
2871 && !test_bit(In_sync
, &rdev
->flags
)
2872 && !rdev_set_badblocks(rdev
, sh
->sector
,
2877 conf
->recovery_disabled
=
2878 conf
->mddev
->recovery_disabled
;
2880 md_done_sync(conf
->mddev
, STRIPE_SECTORS
, !abort
);
2883 static int want_replace(struct stripe_head
*sh
, int disk_idx
)
2885 struct md_rdev
*rdev
;
2887 /* Doing recovery so rcu locking not required */
2888 rdev
= sh
->raid_conf
->disks
[disk_idx
].replacement
;
2890 && !test_bit(Faulty
, &rdev
->flags
)
2891 && !test_bit(In_sync
, &rdev
->flags
)
2892 && (rdev
->recovery_offset
<= sh
->sector
2893 || rdev
->mddev
->recovery_cp
<= sh
->sector
))
2899 /* fetch_block - checks the given member device to see if its data needs
2900 * to be read or computed to satisfy a request.
2902 * Returns 1 when no more member devices need to be checked, otherwise returns
2903 * 0 to tell the loop in handle_stripe_fill to continue
2905 static int fetch_block(struct stripe_head
*sh
, struct stripe_head_state
*s
,
2906 int disk_idx
, int disks
)
2908 struct r5dev
*dev
= &sh
->dev
[disk_idx
];
2909 struct r5dev
*fdev
[2] = { &sh
->dev
[s
->failed_num
[0]],
2910 &sh
->dev
[s
->failed_num
[1]] };
2912 /* is the data in this block needed, and can we get it? */
2913 if (!test_bit(R5_LOCKED
, &dev
->flags
) &&
2914 !test_bit(R5_UPTODATE
, &dev
->flags
) &&
2916 (dev
->towrite
&& !test_bit(R5_OVERWRITE
, &dev
->flags
)) ||
2917 s
->syncing
|| s
->expanding
||
2918 (s
->replacing
&& want_replace(sh
, disk_idx
)) ||
2919 (s
->failed
>= 1 && fdev
[0]->toread
) ||
2920 (s
->failed
>= 2 && fdev
[1]->toread
) ||
2921 (sh
->raid_conf
->level
<= 5 && s
->failed
&& fdev
[0]->towrite
&&
2922 (!test_bit(R5_Insync
, &dev
->flags
) || test_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
)) &&
2923 !test_bit(R5_OVERWRITE
, &fdev
[0]->flags
)) ||
2924 (sh
->raid_conf
->level
== 6 && s
->failed
&& s
->to_write
&&
2925 s
->to_write
- s
->non_overwrite
< sh
->raid_conf
->raid_disks
- 2 &&
2926 (!test_bit(R5_Insync
, &dev
->flags
) || test_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))))) {
2927 /* we would like to get this block, possibly by computing it,
2928 * otherwise read it if the backing disk is insync
2930 BUG_ON(test_bit(R5_Wantcompute
, &dev
->flags
));
2931 BUG_ON(test_bit(R5_Wantread
, &dev
->flags
));
2932 if ((s
->uptodate
== disks
- 1) &&
2933 (s
->failed
&& (disk_idx
== s
->failed_num
[0] ||
2934 disk_idx
== s
->failed_num
[1]))) {
2935 /* have disk failed, and we're requested to fetch it;
2938 pr_debug("Computing stripe %llu block %d\n",
2939 (unsigned long long)sh
->sector
, disk_idx
);
2940 set_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
2941 set_bit(STRIPE_OP_COMPUTE_BLK
, &s
->ops_request
);
2942 set_bit(R5_Wantcompute
, &dev
->flags
);
2943 sh
->ops
.target
= disk_idx
;
2944 sh
->ops
.target2
= -1; /* no 2nd target */
2946 /* Careful: from this point on 'uptodate' is in the eye
2947 * of raid_run_ops which services 'compute' operations
2948 * before writes. R5_Wantcompute flags a block that will
2949 * be R5_UPTODATE by the time it is needed for a
2950 * subsequent operation.
2954 } else if (s
->uptodate
== disks
-2 && s
->failed
>= 2) {
2955 /* Computing 2-failure is *very* expensive; only
2956 * do it if failed >= 2
2959 for (other
= disks
; other
--; ) {
2960 if (other
== disk_idx
)
2962 if (!test_bit(R5_UPTODATE
,
2963 &sh
->dev
[other
].flags
))
2967 pr_debug("Computing stripe %llu blocks %d,%d\n",
2968 (unsigned long long)sh
->sector
,
2970 set_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
2971 set_bit(STRIPE_OP_COMPUTE_BLK
, &s
->ops_request
);
2972 set_bit(R5_Wantcompute
, &sh
->dev
[disk_idx
].flags
);
2973 set_bit(R5_Wantcompute
, &sh
->dev
[other
].flags
);
2974 sh
->ops
.target
= disk_idx
;
2975 sh
->ops
.target2
= other
;
2979 } else if (test_bit(R5_Insync
, &dev
->flags
)) {
2980 set_bit(R5_LOCKED
, &dev
->flags
);
2981 set_bit(R5_Wantread
, &dev
->flags
);
2983 pr_debug("Reading block %d (sync=%d)\n",
2984 disk_idx
, s
->syncing
);
2992 * handle_stripe_fill - read or compute data to satisfy pending requests.
2994 static void handle_stripe_fill(struct stripe_head
*sh
,
2995 struct stripe_head_state
*s
,
3000 /* look for blocks to read/compute, skip this if a compute
3001 * is already in flight, or if the stripe contents are in the
3002 * midst of changing due to a write
3004 if (!test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
) && !sh
->check_state
&&
3005 !sh
->reconstruct_state
)
3006 for (i
= disks
; i
--; )
3007 if (fetch_block(sh
, s
, i
, disks
))
3009 set_bit(STRIPE_HANDLE
, &sh
->state
);
3013 /* handle_stripe_clean_event
3014 * any written block on an uptodate or failed drive can be returned.
3015 * Note that if we 'wrote' to a failed drive, it will be UPTODATE, but
3016 * never LOCKED, so we don't need to test 'failed' directly.
3018 static void handle_stripe_clean_event(struct r5conf
*conf
,
3019 struct stripe_head
*sh
, int disks
, struct bio
**return_bi
)
3023 int discard_pending
= 0;
3025 for (i
= disks
; i
--; )
3026 if (sh
->dev
[i
].written
) {
3028 if (!test_bit(R5_LOCKED
, &dev
->flags
) &&
3029 (test_bit(R5_UPTODATE
, &dev
->flags
) ||
3030 test_bit(R5_Discard
, &dev
->flags
) ||
3031 test_bit(R5_SkipCopy
, &dev
->flags
))) {
3032 /* We can return any write requests */
3033 struct bio
*wbi
, *wbi2
;
3034 pr_debug("Return write for disc %d\n", i
);
3035 if (test_and_clear_bit(R5_Discard
, &dev
->flags
))
3036 clear_bit(R5_UPTODATE
, &dev
->flags
);
3037 if (test_and_clear_bit(R5_SkipCopy
, &dev
->flags
)) {
3038 WARN_ON(test_bit(R5_UPTODATE
, &dev
->flags
));
3039 dev
->page
= dev
->orig_page
;
3042 dev
->written
= NULL
;
3043 while (wbi
&& wbi
->bi_iter
.bi_sector
<
3044 dev
->sector
+ STRIPE_SECTORS
) {
3045 wbi2
= r5_next_bio(wbi
, dev
->sector
);
3046 if (!raid5_dec_bi_active_stripes(wbi
)) {
3047 md_write_end(conf
->mddev
);
3048 wbi
->bi_next
= *return_bi
;
3053 bitmap_endwrite(conf
->mddev
->bitmap
, sh
->sector
,
3055 !test_bit(STRIPE_DEGRADED
, &sh
->state
),
3057 } else if (test_bit(R5_Discard
, &dev
->flags
))
3058 discard_pending
= 1;
3059 WARN_ON(test_bit(R5_SkipCopy
, &dev
->flags
));
3060 WARN_ON(dev
->page
!= dev
->orig_page
);
3062 if (!discard_pending
&&
3063 test_bit(R5_Discard
, &sh
->dev
[sh
->pd_idx
].flags
)) {
3064 clear_bit(R5_Discard
, &sh
->dev
[sh
->pd_idx
].flags
);
3065 clear_bit(R5_UPTODATE
, &sh
->dev
[sh
->pd_idx
].flags
);
3066 if (sh
->qd_idx
>= 0) {
3067 clear_bit(R5_Discard
, &sh
->dev
[sh
->qd_idx
].flags
);
3068 clear_bit(R5_UPTODATE
, &sh
->dev
[sh
->qd_idx
].flags
);
3070 /* now that discard is done we can proceed with any sync */
3071 clear_bit(STRIPE_DISCARD
, &sh
->state
);
3073 * SCSI discard will change some bio fields and the stripe has
3074 * no updated data, so remove it from hash list and the stripe
3075 * will be reinitialized
3077 spin_lock_irq(&conf
->device_lock
);
3079 spin_unlock_irq(&conf
->device_lock
);
3080 if (test_bit(STRIPE_SYNC_REQUESTED
, &sh
->state
))
3081 set_bit(STRIPE_HANDLE
, &sh
->state
);
3085 if (test_and_clear_bit(STRIPE_FULL_WRITE
, &sh
->state
))
3086 if (atomic_dec_and_test(&conf
->pending_full_writes
))
3087 md_wakeup_thread(conf
->mddev
->thread
);
3090 static void handle_stripe_dirtying(struct r5conf
*conf
,
3091 struct stripe_head
*sh
,
3092 struct stripe_head_state
*s
,
3095 int rmw
= 0, rcw
= 0, i
;
3096 sector_t recovery_cp
= conf
->mddev
->recovery_cp
;
3098 /* RAID6 requires 'rcw' in current implementation.
3099 * Otherwise, check whether resync is now happening or should start.
3100 * If yes, then the array is dirty (after unclean shutdown or
3101 * initial creation), so parity in some stripes might be inconsistent.
3102 * In this case, we need to always do reconstruct-write, to ensure
3103 * that in case of drive failure or read-error correction, we
3104 * generate correct data from the parity.
3106 if (conf
->max_degraded
== 2 ||
3107 (recovery_cp
< MaxSector
&& sh
->sector
>= recovery_cp
)) {
3108 /* Calculate the real rcw later - for now make it
3109 * look like rcw is cheaper
3112 pr_debug("force RCW max_degraded=%u, recovery_cp=%llu sh->sector=%llu\n",
3113 conf
->max_degraded
, (unsigned long long)recovery_cp
,
3114 (unsigned long long)sh
->sector
);
3115 } else for (i
= disks
; i
--; ) {
3116 /* would I have to read this buffer for read_modify_write */
3117 struct r5dev
*dev
= &sh
->dev
[i
];
3118 if ((dev
->towrite
|| i
== sh
->pd_idx
) &&
3119 !test_bit(R5_LOCKED
, &dev
->flags
) &&
3120 !(test_bit(R5_UPTODATE
, &dev
->flags
) ||
3121 test_bit(R5_Wantcompute
, &dev
->flags
))) {
3122 if (test_bit(R5_Insync
, &dev
->flags
))
3125 rmw
+= 2*disks
; /* cannot read it */
3127 /* Would I have to read this buffer for reconstruct_write */
3128 if (!test_bit(R5_OVERWRITE
, &dev
->flags
) && i
!= sh
->pd_idx
&&
3129 !test_bit(R5_LOCKED
, &dev
->flags
) &&
3130 !(test_bit(R5_UPTODATE
, &dev
->flags
) ||
3131 test_bit(R5_Wantcompute
, &dev
->flags
))) {
3132 if (test_bit(R5_Insync
, &dev
->flags
))
3138 pr_debug("for sector %llu, rmw=%d rcw=%d\n",
3139 (unsigned long long)sh
->sector
, rmw
, rcw
);
3140 set_bit(STRIPE_HANDLE
, &sh
->state
);
3141 if (rmw
< rcw
&& rmw
> 0) {
3142 /* prefer read-modify-write, but need to get some data */
3143 if (conf
->mddev
->queue
)
3144 blk_add_trace_msg(conf
->mddev
->queue
,
3145 "raid5 rmw %llu %d",
3146 (unsigned long long)sh
->sector
, rmw
);
3147 for (i
= disks
; i
--; ) {
3148 struct r5dev
*dev
= &sh
->dev
[i
];
3149 if ((dev
->towrite
|| i
== sh
->pd_idx
) &&
3150 !test_bit(R5_LOCKED
, &dev
->flags
) &&
3151 !(test_bit(R5_UPTODATE
, &dev
->flags
) ||
3152 test_bit(R5_Wantcompute
, &dev
->flags
)) &&
3153 test_bit(R5_Insync
, &dev
->flags
)) {
3154 if (test_bit(STRIPE_PREREAD_ACTIVE
,
3156 pr_debug("Read_old block %d for r-m-w\n",
3158 set_bit(R5_LOCKED
, &dev
->flags
);
3159 set_bit(R5_Wantread
, &dev
->flags
);
3162 set_bit(STRIPE_DELAYED
, &sh
->state
);
3163 set_bit(STRIPE_HANDLE
, &sh
->state
);
3168 if (rcw
<= rmw
&& rcw
> 0) {
3169 /* want reconstruct write, but need to get some data */
3172 for (i
= disks
; i
--; ) {
3173 struct r5dev
*dev
= &sh
->dev
[i
];
3174 if (!test_bit(R5_OVERWRITE
, &dev
->flags
) &&
3175 i
!= sh
->pd_idx
&& i
!= sh
->qd_idx
&&
3176 !test_bit(R5_LOCKED
, &dev
->flags
) &&
3177 !(test_bit(R5_UPTODATE
, &dev
->flags
) ||
3178 test_bit(R5_Wantcompute
, &dev
->flags
))) {
3180 if (test_bit(R5_Insync
, &dev
->flags
) &&
3181 test_bit(STRIPE_PREREAD_ACTIVE
,
3183 pr_debug("Read_old block "
3184 "%d for Reconstruct\n", i
);
3185 set_bit(R5_LOCKED
, &dev
->flags
);
3186 set_bit(R5_Wantread
, &dev
->flags
);
3190 set_bit(STRIPE_DELAYED
, &sh
->state
);
3191 set_bit(STRIPE_HANDLE
, &sh
->state
);
3195 if (rcw
&& conf
->mddev
->queue
)
3196 blk_add_trace_msg(conf
->mddev
->queue
, "raid5 rcw %llu %d %d %d",
3197 (unsigned long long)sh
->sector
,
3198 rcw
, qread
, test_bit(STRIPE_DELAYED
, &sh
->state
));
3200 /* now if nothing is locked, and if we have enough data,
3201 * we can start a write request
3203 /* since handle_stripe can be called at any time we need to handle the
3204 * case where a compute block operation has been submitted and then a
3205 * subsequent call wants to start a write request. raid_run_ops only
3206 * handles the case where compute block and reconstruct are requested
3207 * simultaneously. If this is not the case then new writes need to be
3208 * held off until the compute completes.
3210 if ((s
->req_compute
|| !test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
)) &&
3211 (s
->locked
== 0 && (rcw
== 0 || rmw
== 0) &&
3212 !test_bit(STRIPE_BIT_DELAY
, &sh
->state
)))
3213 schedule_reconstruction(sh
, s
, rcw
== 0, 0);
3216 static void handle_parity_checks5(struct r5conf
*conf
, struct stripe_head
*sh
,
3217 struct stripe_head_state
*s
, int disks
)
3219 struct r5dev
*dev
= NULL
;
3221 set_bit(STRIPE_HANDLE
, &sh
->state
);
3223 switch (sh
->check_state
) {
3224 case check_state_idle
:
3225 /* start a new check operation if there are no failures */
3226 if (s
->failed
== 0) {
3227 BUG_ON(s
->uptodate
!= disks
);
3228 sh
->check_state
= check_state_run
;
3229 set_bit(STRIPE_OP_CHECK
, &s
->ops_request
);
3230 clear_bit(R5_UPTODATE
, &sh
->dev
[sh
->pd_idx
].flags
);
3234 dev
= &sh
->dev
[s
->failed_num
[0]];
3236 case check_state_compute_result
:
3237 sh
->check_state
= check_state_idle
;
3239 dev
= &sh
->dev
[sh
->pd_idx
];
3241 /* check that a write has not made the stripe insync */
3242 if (test_bit(STRIPE_INSYNC
, &sh
->state
))
3245 /* either failed parity check, or recovery is happening */
3246 BUG_ON(!test_bit(R5_UPTODATE
, &dev
->flags
));
3247 BUG_ON(s
->uptodate
!= disks
);
3249 set_bit(R5_LOCKED
, &dev
->flags
);
3251 set_bit(R5_Wantwrite
, &dev
->flags
);
3253 clear_bit(STRIPE_DEGRADED
, &sh
->state
);
3254 set_bit(STRIPE_INSYNC
, &sh
->state
);
3256 case check_state_run
:
3257 break; /* we will be called again upon completion */
3258 case check_state_check_result
:
3259 sh
->check_state
= check_state_idle
;
3261 /* if a failure occurred during the check operation, leave
3262 * STRIPE_INSYNC not set and let the stripe be handled again
3267 /* handle a successful check operation, if parity is correct
3268 * we are done. Otherwise update the mismatch count and repair
3269 * parity if !MD_RECOVERY_CHECK
3271 if ((sh
->ops
.zero_sum_result
& SUM_CHECK_P_RESULT
) == 0)
3272 /* parity is correct (on disc,
3273 * not in buffer any more)
3275 set_bit(STRIPE_INSYNC
, &sh
->state
);
3277 atomic64_add(STRIPE_SECTORS
, &conf
->mddev
->resync_mismatches
);
3278 if (test_bit(MD_RECOVERY_CHECK
, &conf
->mddev
->recovery
))
3279 /* don't try to repair!! */
3280 set_bit(STRIPE_INSYNC
, &sh
->state
);
3282 sh
->check_state
= check_state_compute_run
;
3283 set_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
3284 set_bit(STRIPE_OP_COMPUTE_BLK
, &s
->ops_request
);
3285 set_bit(R5_Wantcompute
,
3286 &sh
->dev
[sh
->pd_idx
].flags
);
3287 sh
->ops
.target
= sh
->pd_idx
;
3288 sh
->ops
.target2
= -1;
3293 case check_state_compute_run
:
3296 printk(KERN_ERR
"%s: unknown check_state: %d sector: %llu\n",
3297 __func__
, sh
->check_state
,
3298 (unsigned long long) sh
->sector
);
3304 static void handle_parity_checks6(struct r5conf
*conf
, struct stripe_head
*sh
,
3305 struct stripe_head_state
*s
,
3308 int pd_idx
= sh
->pd_idx
;
3309 int qd_idx
= sh
->qd_idx
;
3312 set_bit(STRIPE_HANDLE
, &sh
->state
);
3314 BUG_ON(s
->failed
> 2);
3316 /* Want to check and possibly repair P and Q.
3317 * However there could be one 'failed' device, in which
3318 * case we can only check one of them, possibly using the
3319 * other to generate missing data
3322 switch (sh
->check_state
) {
3323 case check_state_idle
:
3324 /* start a new check operation if there are < 2 failures */
3325 if (s
->failed
== s
->q_failed
) {
3326 /* The only possible failed device holds Q, so it
3327 * makes sense to check P (If anything else were failed,
3328 * we would have used P to recreate it).
3330 sh
->check_state
= check_state_run
;
3332 if (!s
->q_failed
&& s
->failed
< 2) {
3333 /* Q is not failed, and we didn't use it to generate
3334 * anything, so it makes sense to check it
3336 if (sh
->check_state
== check_state_run
)
3337 sh
->check_state
= check_state_run_pq
;
3339 sh
->check_state
= check_state_run_q
;
3342 /* discard potentially stale zero_sum_result */
3343 sh
->ops
.zero_sum_result
= 0;
3345 if (sh
->check_state
== check_state_run
) {
3346 /* async_xor_zero_sum destroys the contents of P */
3347 clear_bit(R5_UPTODATE
, &sh
->dev
[pd_idx
].flags
);
3350 if (sh
->check_state
>= check_state_run
&&
3351 sh
->check_state
<= check_state_run_pq
) {
3352 /* async_syndrome_zero_sum preserves P and Q, so
3353 * no need to mark them !uptodate here
3355 set_bit(STRIPE_OP_CHECK
, &s
->ops_request
);
3359 /* we have 2-disk failure */
3360 BUG_ON(s
->failed
!= 2);
3362 case check_state_compute_result
:
3363 sh
->check_state
= check_state_idle
;
3365 /* check that a write has not made the stripe insync */
3366 if (test_bit(STRIPE_INSYNC
, &sh
->state
))
3369 /* now write out any block on a failed drive,
3370 * or P or Q if they were recomputed
3372 BUG_ON(s
->uptodate
< disks
- 1); /* We don't need Q to recover */
3373 if (s
->failed
== 2) {
3374 dev
= &sh
->dev
[s
->failed_num
[1]];
3376 set_bit(R5_LOCKED
, &dev
->flags
);
3377 set_bit(R5_Wantwrite
, &dev
->flags
);
3379 if (s
->failed
>= 1) {
3380 dev
= &sh
->dev
[s
->failed_num
[0]];
3382 set_bit(R5_LOCKED
, &dev
->flags
);
3383 set_bit(R5_Wantwrite
, &dev
->flags
);
3385 if (sh
->ops
.zero_sum_result
& SUM_CHECK_P_RESULT
) {
3386 dev
= &sh
->dev
[pd_idx
];
3388 set_bit(R5_LOCKED
, &dev
->flags
);
3389 set_bit(R5_Wantwrite
, &dev
->flags
);
3391 if (sh
->ops
.zero_sum_result
& SUM_CHECK_Q_RESULT
) {
3392 dev
= &sh
->dev
[qd_idx
];
3394 set_bit(R5_LOCKED
, &dev
->flags
);
3395 set_bit(R5_Wantwrite
, &dev
->flags
);
3397 clear_bit(STRIPE_DEGRADED
, &sh
->state
);
3399 set_bit(STRIPE_INSYNC
, &sh
->state
);
3401 case check_state_run
:
3402 case check_state_run_q
:
3403 case check_state_run_pq
:
3404 break; /* we will be called again upon completion */
3405 case check_state_check_result
:
3406 sh
->check_state
= check_state_idle
;
3408 /* handle a successful check operation, if parity is correct
3409 * we are done. Otherwise update the mismatch count and repair
3410 * parity if !MD_RECOVERY_CHECK
3412 if (sh
->ops
.zero_sum_result
== 0) {
3413 /* both parities are correct */
3415 set_bit(STRIPE_INSYNC
, &sh
->state
);
3417 /* in contrast to the raid5 case we can validate
3418 * parity, but still have a failure to write
3421 sh
->check_state
= check_state_compute_result
;
3422 /* Returning at this point means that we may go
3423 * off and bring p and/or q uptodate again so
3424 * we make sure to check zero_sum_result again
3425 * to verify if p or q need writeback
3429 atomic64_add(STRIPE_SECTORS
, &conf
->mddev
->resync_mismatches
);
3430 if (test_bit(MD_RECOVERY_CHECK
, &conf
->mddev
->recovery
))
3431 /* don't try to repair!! */
3432 set_bit(STRIPE_INSYNC
, &sh
->state
);
3434 int *target
= &sh
->ops
.target
;
3436 sh
->ops
.target
= -1;
3437 sh
->ops
.target2
= -1;
3438 sh
->check_state
= check_state_compute_run
;
3439 set_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
3440 set_bit(STRIPE_OP_COMPUTE_BLK
, &s
->ops_request
);
3441 if (sh
->ops
.zero_sum_result
& SUM_CHECK_P_RESULT
) {
3442 set_bit(R5_Wantcompute
,
3443 &sh
->dev
[pd_idx
].flags
);
3445 target
= &sh
->ops
.target2
;
3448 if (sh
->ops
.zero_sum_result
& SUM_CHECK_Q_RESULT
) {
3449 set_bit(R5_Wantcompute
,
3450 &sh
->dev
[qd_idx
].flags
);
3457 case check_state_compute_run
:
3460 printk(KERN_ERR
"%s: unknown check_state: %d sector: %llu\n",
3461 __func__
, sh
->check_state
,
3462 (unsigned long long) sh
->sector
);
3467 static void handle_stripe_expansion(struct r5conf
*conf
, struct stripe_head
*sh
)
3471 /* We have read all the blocks in this stripe and now we need to
3472 * copy some of them into a target stripe for expand.
3474 struct dma_async_tx_descriptor
*tx
= NULL
;
3475 clear_bit(STRIPE_EXPAND_SOURCE
, &sh
->state
);
3476 for (i
= 0; i
< sh
->disks
; i
++)
3477 if (i
!= sh
->pd_idx
&& i
!= sh
->qd_idx
) {
3479 struct stripe_head
*sh2
;
3480 struct async_submit_ctl submit
;
3482 sector_t bn
= compute_blocknr(sh
, i
, 1);
3483 sector_t s
= raid5_compute_sector(conf
, bn
, 0,
3485 sh2
= get_active_stripe(conf
, s
, 0, 1, 1);
3487 /* so far only the early blocks of this stripe
3488 * have been requested. When later blocks
3489 * get requested, we will try again
3492 if (!test_bit(STRIPE_EXPANDING
, &sh2
->state
) ||
3493 test_bit(R5_Expanded
, &sh2
->dev
[dd_idx
].flags
)) {
3494 /* must have already done this block */
3495 release_stripe(sh2
);
3499 /* place all the copies on one channel */
3500 init_async_submit(&submit
, 0, tx
, NULL
, NULL
, NULL
);
3501 tx
= async_memcpy(sh2
->dev
[dd_idx
].page
,
3502 sh
->dev
[i
].page
, 0, 0, STRIPE_SIZE
,
3505 set_bit(R5_Expanded
, &sh2
->dev
[dd_idx
].flags
);
3506 set_bit(R5_UPTODATE
, &sh2
->dev
[dd_idx
].flags
);
3507 for (j
= 0; j
< conf
->raid_disks
; j
++)
3508 if (j
!= sh2
->pd_idx
&&
3510 !test_bit(R5_Expanded
, &sh2
->dev
[j
].flags
))
3512 if (j
== conf
->raid_disks
) {
3513 set_bit(STRIPE_EXPAND_READY
, &sh2
->state
);
3514 set_bit(STRIPE_HANDLE
, &sh2
->state
);
3516 release_stripe(sh2
);
3519 /* done submitting copies, wait for them to complete */
3520 async_tx_quiesce(&tx
);
3524 * handle_stripe - do things to a stripe.
3526 * We lock the stripe by setting STRIPE_ACTIVE and then examine the
3527 * state of various bits to see what needs to be done.
3529 * return some read requests which now have data
3530 * return some write requests which are safely on storage
3531 * schedule a read on some buffers
3532 * schedule a write of some buffers
3533 * return confirmation of parity correctness
3537 static void analyse_stripe(struct stripe_head
*sh
, struct stripe_head_state
*s
)
3539 struct r5conf
*conf
= sh
->raid_conf
;
3540 int disks
= sh
->disks
;
3543 int do_recovery
= 0;
3545 memset(s
, 0, sizeof(*s
));
3547 s
->expanding
= test_bit(STRIPE_EXPAND_SOURCE
, &sh
->state
);
3548 s
->expanded
= test_bit(STRIPE_EXPAND_READY
, &sh
->state
);
3549 s
->failed_num
[0] = -1;
3550 s
->failed_num
[1] = -1;
3552 /* Now to look around and see what can be done */
3554 for (i
=disks
; i
--; ) {
3555 struct md_rdev
*rdev
;
3562 pr_debug("check %d: state 0x%lx read %p write %p written %p\n",
3564 dev
->toread
, dev
->towrite
, dev
->written
);
3565 /* maybe we can reply to a read
3567 * new wantfill requests are only permitted while
3568 * ops_complete_biofill is guaranteed to be inactive
3570 if (test_bit(R5_UPTODATE
, &dev
->flags
) && dev
->toread
&&
3571 !test_bit(STRIPE_BIOFILL_RUN
, &sh
->state
))
3572 set_bit(R5_Wantfill
, &dev
->flags
);
3574 /* now count some things */
3575 if (test_bit(R5_LOCKED
, &dev
->flags
))
3577 if (test_bit(R5_UPTODATE
, &dev
->flags
))
3579 if (test_bit(R5_Wantcompute
, &dev
->flags
)) {
3581 BUG_ON(s
->compute
> 2);
3584 if (test_bit(R5_Wantfill
, &dev
->flags
))
3586 else if (dev
->toread
)
3590 if (!test_bit(R5_OVERWRITE
, &dev
->flags
))
3595 /* Prefer to use the replacement for reads, but only
3596 * if it is recovered enough and has no bad blocks.
3598 rdev
= rcu_dereference(conf
->disks
[i
].replacement
);
3599 if (rdev
&& !test_bit(Faulty
, &rdev
->flags
) &&
3600 rdev
->recovery_offset
>= sh
->sector
+ STRIPE_SECTORS
&&
3601 !is_badblock(rdev
, sh
->sector
, STRIPE_SECTORS
,
3602 &first_bad
, &bad_sectors
))
3603 set_bit(R5_ReadRepl
, &dev
->flags
);
3606 set_bit(R5_NeedReplace
, &dev
->flags
);
3607 rdev
= rcu_dereference(conf
->disks
[i
].rdev
);
3608 clear_bit(R5_ReadRepl
, &dev
->flags
);
3610 if (rdev
&& test_bit(Faulty
, &rdev
->flags
))
3613 is_bad
= is_badblock(rdev
, sh
->sector
, STRIPE_SECTORS
,
3614 &first_bad
, &bad_sectors
);
3615 if (s
->blocked_rdev
== NULL
3616 && (test_bit(Blocked
, &rdev
->flags
)
3619 set_bit(BlockedBadBlocks
,
3621 s
->blocked_rdev
= rdev
;
3622 atomic_inc(&rdev
->nr_pending
);
3625 clear_bit(R5_Insync
, &dev
->flags
);
3629 /* also not in-sync */
3630 if (!test_bit(WriteErrorSeen
, &rdev
->flags
) &&
3631 test_bit(R5_UPTODATE
, &dev
->flags
)) {
3632 /* treat as in-sync, but with a read error
3633 * which we can now try to correct
3635 set_bit(R5_Insync
, &dev
->flags
);
3636 set_bit(R5_ReadError
, &dev
->flags
);
3638 } else if (test_bit(In_sync
, &rdev
->flags
))
3639 set_bit(R5_Insync
, &dev
->flags
);
3640 else if (sh
->sector
+ STRIPE_SECTORS
<= rdev
->recovery_offset
)
3641 /* in sync if before recovery_offset */
3642 set_bit(R5_Insync
, &dev
->flags
);
3643 else if (test_bit(R5_UPTODATE
, &dev
->flags
) &&
3644 test_bit(R5_Expanded
, &dev
->flags
))
3645 /* If we've reshaped into here, we assume it is Insync.
3646 * We will shortly update recovery_offset to make
3649 set_bit(R5_Insync
, &dev
->flags
);
3651 if (test_bit(R5_WriteError
, &dev
->flags
)) {
3652 /* This flag does not apply to '.replacement'
3653 * only to .rdev, so make sure to check that*/
3654 struct md_rdev
*rdev2
= rcu_dereference(
3655 conf
->disks
[i
].rdev
);
3657 clear_bit(R5_Insync
, &dev
->flags
);
3658 if (rdev2
&& !test_bit(Faulty
, &rdev2
->flags
)) {
3659 s
->handle_bad_blocks
= 1;
3660 atomic_inc(&rdev2
->nr_pending
);
3662 clear_bit(R5_WriteError
, &dev
->flags
);
3664 if (test_bit(R5_MadeGood
, &dev
->flags
)) {
3665 /* This flag does not apply to '.replacement'
3666 * only to .rdev, so make sure to check that*/
3667 struct md_rdev
*rdev2
= rcu_dereference(
3668 conf
->disks
[i
].rdev
);
3669 if (rdev2
&& !test_bit(Faulty
, &rdev2
->flags
)) {
3670 s
->handle_bad_blocks
= 1;
3671 atomic_inc(&rdev2
->nr_pending
);
3673 clear_bit(R5_MadeGood
, &dev
->flags
);
3675 if (test_bit(R5_MadeGoodRepl
, &dev
->flags
)) {
3676 struct md_rdev
*rdev2
= rcu_dereference(
3677 conf
->disks
[i
].replacement
);
3678 if (rdev2
&& !test_bit(Faulty
, &rdev2
->flags
)) {
3679 s
->handle_bad_blocks
= 1;
3680 atomic_inc(&rdev2
->nr_pending
);
3682 clear_bit(R5_MadeGoodRepl
, &dev
->flags
);
3684 if (!test_bit(R5_Insync
, &dev
->flags
)) {
3685 /* The ReadError flag will just be confusing now */
3686 clear_bit(R5_ReadError
, &dev
->flags
);
3687 clear_bit(R5_ReWrite
, &dev
->flags
);
3689 if (test_bit(R5_ReadError
, &dev
->flags
))
3690 clear_bit(R5_Insync
, &dev
->flags
);
3691 if (!test_bit(R5_Insync
, &dev
->flags
)) {
3693 s
->failed_num
[s
->failed
] = i
;
3695 if (rdev
&& !test_bit(Faulty
, &rdev
->flags
))
3699 if (test_bit(STRIPE_SYNCING
, &sh
->state
)) {
3700 /* If there is a failed device being replaced,
3701 * we must be recovering.
3702 * else if we are after recovery_cp, we must be syncing
3703 * else if MD_RECOVERY_REQUESTED is set, we also are syncing.
3704 * else we can only be replacing
3705 * sync and recovery both need to read all devices, and so
3706 * use the same flag.
3709 sh
->sector
>= conf
->mddev
->recovery_cp
||
3710 test_bit(MD_RECOVERY_REQUESTED
, &(conf
->mddev
->recovery
)))
3718 static void handle_stripe(struct stripe_head
*sh
)
3720 struct stripe_head_state s
;
3721 struct r5conf
*conf
= sh
->raid_conf
;
3724 int disks
= sh
->disks
;
3725 struct r5dev
*pdev
, *qdev
;
3727 clear_bit(STRIPE_HANDLE
, &sh
->state
);
3728 if (test_and_set_bit_lock(STRIPE_ACTIVE
, &sh
->state
)) {
3729 /* already being handled, ensure it gets handled
3730 * again when current action finishes */
3731 set_bit(STRIPE_HANDLE
, &sh
->state
);
3735 if (test_bit(STRIPE_SYNC_REQUESTED
, &sh
->state
)) {
3736 spin_lock(&sh
->stripe_lock
);
3737 /* Cannot process 'sync' concurrently with 'discard' */
3738 if (!test_bit(STRIPE_DISCARD
, &sh
->state
) &&
3739 test_and_clear_bit(STRIPE_SYNC_REQUESTED
, &sh
->state
)) {
3740 set_bit(STRIPE_SYNCING
, &sh
->state
);
3741 clear_bit(STRIPE_INSYNC
, &sh
->state
);
3742 clear_bit(STRIPE_REPLACED
, &sh
->state
);
3744 spin_unlock(&sh
->stripe_lock
);
3746 clear_bit(STRIPE_DELAYED
, &sh
->state
);
3748 pr_debug("handling stripe %llu, state=%#lx cnt=%d, "
3749 "pd_idx=%d, qd_idx=%d\n, check:%d, reconstruct:%d\n",
3750 (unsigned long long)sh
->sector
, sh
->state
,
3751 atomic_read(&sh
->count
), sh
->pd_idx
, sh
->qd_idx
,
3752 sh
->check_state
, sh
->reconstruct_state
);
3754 analyse_stripe(sh
, &s
);
3756 if (s
.handle_bad_blocks
) {
3757 set_bit(STRIPE_HANDLE
, &sh
->state
);
3761 if (unlikely(s
.blocked_rdev
)) {
3762 if (s
.syncing
|| s
.expanding
|| s
.expanded
||
3763 s
.replacing
|| s
.to_write
|| s
.written
) {
3764 set_bit(STRIPE_HANDLE
, &sh
->state
);
3767 /* There is nothing for the blocked_rdev to block */
3768 rdev_dec_pending(s
.blocked_rdev
, conf
->mddev
);
3769 s
.blocked_rdev
= NULL
;
3772 if (s
.to_fill
&& !test_bit(STRIPE_BIOFILL_RUN
, &sh
->state
)) {
3773 set_bit(STRIPE_OP_BIOFILL
, &s
.ops_request
);
3774 set_bit(STRIPE_BIOFILL_RUN
, &sh
->state
);
3777 pr_debug("locked=%d uptodate=%d to_read=%d"
3778 " to_write=%d failed=%d failed_num=%d,%d\n",
3779 s
.locked
, s
.uptodate
, s
.to_read
, s
.to_write
, s
.failed
,
3780 s
.failed_num
[0], s
.failed_num
[1]);
3781 /* check if the array has lost more than max_degraded devices and,
3782 * if so, some requests might need to be failed.
3784 if (s
.failed
> conf
->max_degraded
) {
3785 sh
->check_state
= 0;
3786 sh
->reconstruct_state
= 0;
3787 if (s
.to_read
+s
.to_write
+s
.written
)
3788 handle_failed_stripe(conf
, sh
, &s
, disks
, &s
.return_bi
);
3789 if (s
.syncing
+ s
.replacing
)
3790 handle_failed_sync(conf
, sh
, &s
);
3793 /* Now we check to see if any write operations have recently
3797 if (sh
->reconstruct_state
== reconstruct_state_prexor_drain_result
)
3799 if (sh
->reconstruct_state
== reconstruct_state_drain_result
||
3800 sh
->reconstruct_state
== reconstruct_state_prexor_drain_result
) {
3801 sh
->reconstruct_state
= reconstruct_state_idle
;
3803 /* All the 'written' buffers and the parity block are ready to
3804 * be written back to disk
3806 BUG_ON(!test_bit(R5_UPTODATE
, &sh
->dev
[sh
->pd_idx
].flags
) &&
3807 !test_bit(R5_Discard
, &sh
->dev
[sh
->pd_idx
].flags
));
3808 BUG_ON(sh
->qd_idx
>= 0 &&
3809 !test_bit(R5_UPTODATE
, &sh
->dev
[sh
->qd_idx
].flags
) &&
3810 !test_bit(R5_Discard
, &sh
->dev
[sh
->qd_idx
].flags
));
3811 for (i
= disks
; i
--; ) {
3812 struct r5dev
*dev
= &sh
->dev
[i
];
3813 if (test_bit(R5_LOCKED
, &dev
->flags
) &&
3814 (i
== sh
->pd_idx
|| i
== sh
->qd_idx
||
3816 pr_debug("Writing block %d\n", i
);
3817 set_bit(R5_Wantwrite
, &dev
->flags
);
3822 if (!test_bit(R5_Insync
, &dev
->flags
) ||
3823 ((i
== sh
->pd_idx
|| i
== sh
->qd_idx
) &&
3825 set_bit(STRIPE_INSYNC
, &sh
->state
);
3828 if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
3829 s
.dec_preread_active
= 1;
3833 * might be able to return some write requests if the parity blocks
3834 * are safe, or on a failed drive
3836 pdev
= &sh
->dev
[sh
->pd_idx
];
3837 s
.p_failed
= (s
.failed
>= 1 && s
.failed_num
[0] == sh
->pd_idx
)
3838 || (s
.failed
>= 2 && s
.failed_num
[1] == sh
->pd_idx
);
3839 qdev
= &sh
->dev
[sh
->qd_idx
];
3840 s
.q_failed
= (s
.failed
>= 1 && s
.failed_num
[0] == sh
->qd_idx
)
3841 || (s
.failed
>= 2 && s
.failed_num
[1] == sh
->qd_idx
)
3845 (s
.p_failed
|| ((test_bit(R5_Insync
, &pdev
->flags
)
3846 && !test_bit(R5_LOCKED
, &pdev
->flags
)
3847 && (test_bit(R5_UPTODATE
, &pdev
->flags
) ||
3848 test_bit(R5_Discard
, &pdev
->flags
))))) &&
3849 (s
.q_failed
|| ((test_bit(R5_Insync
, &qdev
->flags
)
3850 && !test_bit(R5_LOCKED
, &qdev
->flags
)
3851 && (test_bit(R5_UPTODATE
, &qdev
->flags
) ||
3852 test_bit(R5_Discard
, &qdev
->flags
))))))
3853 handle_stripe_clean_event(conf
, sh
, disks
, &s
.return_bi
);
3855 /* Now we might consider reading some blocks, either to check/generate
3856 * parity, or to satisfy requests
3857 * or to load a block that is being partially written.
3859 if (s
.to_read
|| s
.non_overwrite
3860 || (conf
->level
== 6 && s
.to_write
&& s
.failed
)
3861 || (s
.syncing
&& (s
.uptodate
+ s
.compute
< disks
))
3864 handle_stripe_fill(sh
, &s
, disks
);
3866 /* Now to consider new write requests and what else, if anything
3867 * should be read. We do not handle new writes when:
3868 * 1/ A 'write' operation (copy+xor) is already in flight.
3869 * 2/ A 'check' operation is in flight, as it may clobber the parity
3872 if (s
.to_write
&& !sh
->reconstruct_state
&& !sh
->check_state
)
3873 handle_stripe_dirtying(conf
, sh
, &s
, disks
);
3875 /* maybe we need to check and possibly fix the parity for this stripe
3876 * Any reads will already have been scheduled, so we just see if enough
3877 * data is available. The parity check is held off while parity
3878 * dependent operations are in flight.
3880 if (sh
->check_state
||
3881 (s
.syncing
&& s
.locked
== 0 &&
3882 !test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
) &&
3883 !test_bit(STRIPE_INSYNC
, &sh
->state
))) {
3884 if (conf
->level
== 6)
3885 handle_parity_checks6(conf
, sh
, &s
, disks
);
3887 handle_parity_checks5(conf
, sh
, &s
, disks
);
3890 if ((s
.replacing
|| s
.syncing
) && s
.locked
== 0
3891 && !test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
)
3892 && !test_bit(STRIPE_REPLACED
, &sh
->state
)) {
3893 /* Write out to replacement devices where possible */
3894 for (i
= 0; i
< conf
->raid_disks
; i
++)
3895 if (test_bit(R5_NeedReplace
, &sh
->dev
[i
].flags
)) {
3896 WARN_ON(!test_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
));
3897 set_bit(R5_WantReplace
, &sh
->dev
[i
].flags
);
3898 set_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
3902 set_bit(STRIPE_INSYNC
, &sh
->state
);
3903 set_bit(STRIPE_REPLACED
, &sh
->state
);
3905 if ((s
.syncing
|| s
.replacing
) && s
.locked
== 0 &&
3906 !test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
) &&
3907 test_bit(STRIPE_INSYNC
, &sh
->state
)) {
3908 md_done_sync(conf
->mddev
, STRIPE_SECTORS
, 1);
3909 clear_bit(STRIPE_SYNCING
, &sh
->state
);
3910 if (test_and_clear_bit(R5_Overlap
, &sh
->dev
[sh
->pd_idx
].flags
))
3911 wake_up(&conf
->wait_for_overlap
);
3914 /* If the failed drives are just a ReadError, then we might need
3915 * to progress the repair/check process
3917 if (s
.failed
<= conf
->max_degraded
&& !conf
->mddev
->ro
)
3918 for (i
= 0; i
< s
.failed
; i
++) {
3919 struct r5dev
*dev
= &sh
->dev
[s
.failed_num
[i
]];
3920 if (test_bit(R5_ReadError
, &dev
->flags
)
3921 && !test_bit(R5_LOCKED
, &dev
->flags
)
3922 && test_bit(R5_UPTODATE
, &dev
->flags
)
3924 if (!test_bit(R5_ReWrite
, &dev
->flags
)) {
3925 set_bit(R5_Wantwrite
, &dev
->flags
);
3926 set_bit(R5_ReWrite
, &dev
->flags
);
3927 set_bit(R5_LOCKED
, &dev
->flags
);
3930 /* let's read it back */
3931 set_bit(R5_Wantread
, &dev
->flags
);
3932 set_bit(R5_LOCKED
, &dev
->flags
);
3939 /* Finish reconstruct operations initiated by the expansion process */
3940 if (sh
->reconstruct_state
== reconstruct_state_result
) {
3941 struct stripe_head
*sh_src
3942 = get_active_stripe(conf
, sh
->sector
, 1, 1, 1);
3943 if (sh_src
&& test_bit(STRIPE_EXPAND_SOURCE
, &sh_src
->state
)) {
3944 /* sh cannot be written until sh_src has been read.
3945 * so arrange for sh to be delayed a little
3947 set_bit(STRIPE_DELAYED
, &sh
->state
);
3948 set_bit(STRIPE_HANDLE
, &sh
->state
);
3949 if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE
,
3951 atomic_inc(&conf
->preread_active_stripes
);
3952 release_stripe(sh_src
);
3956 release_stripe(sh_src
);
3958 sh
->reconstruct_state
= reconstruct_state_idle
;
3959 clear_bit(STRIPE_EXPANDING
, &sh
->state
);
3960 for (i
= conf
->raid_disks
; i
--; ) {
3961 set_bit(R5_Wantwrite
, &sh
->dev
[i
].flags
);
3962 set_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
3967 if (s
.expanded
&& test_bit(STRIPE_EXPANDING
, &sh
->state
) &&
3968 !sh
->reconstruct_state
) {
3969 /* Need to write out all blocks after computing parity */
3970 sh
->disks
= conf
->raid_disks
;
3971 stripe_set_idx(sh
->sector
, conf
, 0, sh
);
3972 schedule_reconstruction(sh
, &s
, 1, 1);
3973 } else if (s
.expanded
&& !sh
->reconstruct_state
&& s
.locked
== 0) {
3974 clear_bit(STRIPE_EXPAND_READY
, &sh
->state
);
3975 atomic_dec(&conf
->reshape_stripes
);
3976 wake_up(&conf
->wait_for_overlap
);
3977 md_done_sync(conf
->mddev
, STRIPE_SECTORS
, 1);
3980 if (s
.expanding
&& s
.locked
== 0 &&
3981 !test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
))
3982 handle_stripe_expansion(conf
, sh
);
3985 /* wait for this device to become unblocked */
3986 if (unlikely(s
.blocked_rdev
)) {
3987 if (conf
->mddev
->external
)
3988 md_wait_for_blocked_rdev(s
.blocked_rdev
,
3991 /* Internal metadata will immediately
3992 * be written by raid5d, so we don't
3993 * need to wait here.
3995 rdev_dec_pending(s
.blocked_rdev
,
3999 if (s
.handle_bad_blocks
)
4000 for (i
= disks
; i
--; ) {
4001 struct md_rdev
*rdev
;
4002 struct r5dev
*dev
= &sh
->dev
[i
];
4003 if (test_and_clear_bit(R5_WriteError
, &dev
->flags
)) {
4004 /* We own a safe reference to the rdev */
4005 rdev
= conf
->disks
[i
].rdev
;
4006 if (!rdev_set_badblocks(rdev
, sh
->sector
,
4008 md_error(conf
->mddev
, rdev
);
4009 rdev_dec_pending(rdev
, conf
->mddev
);
4011 if (test_and_clear_bit(R5_MadeGood
, &dev
->flags
)) {
4012 rdev
= conf
->disks
[i
].rdev
;
4013 rdev_clear_badblocks(rdev
, sh
->sector
,
4015 rdev_dec_pending(rdev
, conf
->mddev
);
4017 if (test_and_clear_bit(R5_MadeGoodRepl
, &dev
->flags
)) {
4018 rdev
= conf
->disks
[i
].replacement
;
4020 /* rdev have been moved down */
4021 rdev
= conf
->disks
[i
].rdev
;
4022 rdev_clear_badblocks(rdev
, sh
->sector
,
4024 rdev_dec_pending(rdev
, conf
->mddev
);
4029 raid_run_ops(sh
, s
.ops_request
);
4033 if (s
.dec_preread_active
) {
4034 /* We delay this until after ops_run_io so that if make_request
4035 * is waiting on a flush, it won't continue until the writes
4036 * have actually been submitted.
4038 atomic_dec(&conf
->preread_active_stripes
);
4039 if (atomic_read(&conf
->preread_active_stripes
) <
4041 md_wakeup_thread(conf
->mddev
->thread
);
4044 return_io(s
.return_bi
);
4046 clear_bit_unlock(STRIPE_ACTIVE
, &sh
->state
);
4049 static void raid5_activate_delayed(struct r5conf
*conf
)
4051 if (atomic_read(&conf
->preread_active_stripes
) < IO_THRESHOLD
) {
4052 while (!list_empty(&conf
->delayed_list
)) {
4053 struct list_head
*l
= conf
->delayed_list
.next
;
4054 struct stripe_head
*sh
;
4055 sh
= list_entry(l
, struct stripe_head
, lru
);
4057 clear_bit(STRIPE_DELAYED
, &sh
->state
);
4058 if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
4059 atomic_inc(&conf
->preread_active_stripes
);
4060 list_add_tail(&sh
->lru
, &conf
->hold_list
);
4061 raid5_wakeup_stripe_thread(sh
);
4066 static void activate_bit_delay(struct r5conf
*conf
,
4067 struct list_head
*temp_inactive_list
)
4069 /* device_lock is held */
4070 struct list_head head
;
4071 list_add(&head
, &conf
->bitmap_list
);
4072 list_del_init(&conf
->bitmap_list
);
4073 while (!list_empty(&head
)) {
4074 struct stripe_head
*sh
= list_entry(head
.next
, struct stripe_head
, lru
);
4076 list_del_init(&sh
->lru
);
4077 atomic_inc(&sh
->count
);
4078 hash
= sh
->hash_lock_index
;
4079 __release_stripe(conf
, sh
, &temp_inactive_list
[hash
]);
4083 int md_raid5_congested(struct mddev
*mddev
, int bits
)
4085 struct r5conf
*conf
= mddev
->private;
4087 /* No difference between reads and writes. Just check
4088 * how busy the stripe_cache is
4091 if (conf
->inactive_blocked
)
4095 if (atomic_read(&conf
->empty_inactive_list_nr
))
4100 EXPORT_SYMBOL_GPL(md_raid5_congested
);
4102 static int raid5_congested(void *data
, int bits
)
4104 struct mddev
*mddev
= data
;
4106 return mddev_congested(mddev
, bits
) ||
4107 md_raid5_congested(mddev
, bits
);
4110 /* We want read requests to align with chunks where possible,
4111 * but write requests don't need to.
4113 static int raid5_mergeable_bvec(struct request_queue
*q
,
4114 struct bvec_merge_data
*bvm
,
4115 struct bio_vec
*biovec
)
4117 struct mddev
*mddev
= q
->queuedata
;
4118 sector_t sector
= bvm
->bi_sector
+ get_start_sect(bvm
->bi_bdev
);
4120 unsigned int chunk_sectors
= mddev
->chunk_sectors
;
4121 unsigned int bio_sectors
= bvm
->bi_size
>> 9;
4123 if ((bvm
->bi_rw
& 1) == WRITE
)
4124 return biovec
->bv_len
; /* always allow writes to be mergeable */
4126 if (mddev
->new_chunk_sectors
< mddev
->chunk_sectors
)
4127 chunk_sectors
= mddev
->new_chunk_sectors
;
4128 max
= (chunk_sectors
- ((sector
& (chunk_sectors
- 1)) + bio_sectors
)) << 9;
4129 if (max
< 0) max
= 0;
4130 if (max
<= biovec
->bv_len
&& bio_sectors
== 0)
4131 return biovec
->bv_len
;
4137 static int in_chunk_boundary(struct mddev
*mddev
, struct bio
*bio
)
4139 sector_t sector
= bio
->bi_iter
.bi_sector
+ get_start_sect(bio
->bi_bdev
);
4140 unsigned int chunk_sectors
= mddev
->chunk_sectors
;
4141 unsigned int bio_sectors
= bio_sectors(bio
);
4143 if (mddev
->new_chunk_sectors
< mddev
->chunk_sectors
)
4144 chunk_sectors
= mddev
->new_chunk_sectors
;
4145 return chunk_sectors
>=
4146 ((sector
& (chunk_sectors
- 1)) + bio_sectors
);
4150 * add bio to the retry LIFO ( in O(1) ... we are in interrupt )
4151 * later sampled by raid5d.
4153 static void add_bio_to_retry(struct bio
*bi
,struct r5conf
*conf
)
4155 unsigned long flags
;
4157 spin_lock_irqsave(&conf
->device_lock
, flags
);
4159 bi
->bi_next
= conf
->retry_read_aligned_list
;
4160 conf
->retry_read_aligned_list
= bi
;
4162 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
4163 md_wakeup_thread(conf
->mddev
->thread
);
4167 static struct bio
*remove_bio_from_retry(struct r5conf
*conf
)
4171 bi
= conf
->retry_read_aligned
;
4173 conf
->retry_read_aligned
= NULL
;
4176 bi
= conf
->retry_read_aligned_list
;
4178 conf
->retry_read_aligned_list
= bi
->bi_next
;
4181 * this sets the active strip count to 1 and the processed
4182 * strip count to zero (upper 8 bits)
4184 raid5_set_bi_stripes(bi
, 1); /* biased count of active stripes */
4192 * The "raid5_align_endio" should check if the read succeeded and if it
4193 * did, call bio_endio on the original bio (having bio_put the new bio
4195 * If the read failed..
4197 static void raid5_align_endio(struct bio
*bi
, int error
)
4199 struct bio
* raid_bi
= bi
->bi_private
;
4200 struct mddev
*mddev
;
4201 struct r5conf
*conf
;
4202 int uptodate
= test_bit(BIO_UPTODATE
, &bi
->bi_flags
);
4203 struct md_rdev
*rdev
;
4207 rdev
= (void*)raid_bi
->bi_next
;
4208 raid_bi
->bi_next
= NULL
;
4209 mddev
= rdev
->mddev
;
4210 conf
= mddev
->private;
4212 rdev_dec_pending(rdev
, conf
->mddev
);
4214 if (!error
&& uptodate
) {
4215 trace_block_bio_complete(bdev_get_queue(raid_bi
->bi_bdev
),
4217 bio_endio(raid_bi
, 0);
4218 if (atomic_dec_and_test(&conf
->active_aligned_reads
))
4219 wake_up(&conf
->wait_for_stripe
);
4224 pr_debug("raid5_align_endio : io error...handing IO for a retry\n");
4226 add_bio_to_retry(raid_bi
, conf
);
4229 static int bio_fits_rdev(struct bio
*bi
)
4231 struct request_queue
*q
= bdev_get_queue(bi
->bi_bdev
);
4233 if (bio_sectors(bi
) > queue_max_sectors(q
))
4235 blk_recount_segments(q
, bi
);
4236 if (bi
->bi_phys_segments
> queue_max_segments(q
))
4239 if (q
->merge_bvec_fn
)
4240 /* it's too hard to apply the merge_bvec_fn at this stage,
4249 static int chunk_aligned_read(struct mddev
*mddev
, struct bio
* raid_bio
)
4251 struct r5conf
*conf
= mddev
->private;
4253 struct bio
* align_bi
;
4254 struct md_rdev
*rdev
;
4255 sector_t end_sector
;
4257 if (!in_chunk_boundary(mddev
, raid_bio
)) {
4258 pr_debug("chunk_aligned_read : non aligned\n");
4262 * use bio_clone_mddev to make a copy of the bio
4264 align_bi
= bio_clone_mddev(raid_bio
, GFP_NOIO
, mddev
);
4268 * set bi_end_io to a new function, and set bi_private to the
4271 align_bi
->bi_end_io
= raid5_align_endio
;
4272 align_bi
->bi_private
= raid_bio
;
4276 align_bi
->bi_iter
.bi_sector
=
4277 raid5_compute_sector(conf
, raid_bio
->bi_iter
.bi_sector
,
4280 end_sector
= bio_end_sector(align_bi
);
4282 rdev
= rcu_dereference(conf
->disks
[dd_idx
].replacement
);
4283 if (!rdev
|| test_bit(Faulty
, &rdev
->flags
) ||
4284 rdev
->recovery_offset
< end_sector
) {
4285 rdev
= rcu_dereference(conf
->disks
[dd_idx
].rdev
);
4287 (test_bit(Faulty
, &rdev
->flags
) ||
4288 !(test_bit(In_sync
, &rdev
->flags
) ||
4289 rdev
->recovery_offset
>= end_sector
)))
4296 atomic_inc(&rdev
->nr_pending
);
4298 raid_bio
->bi_next
= (void*)rdev
;
4299 align_bi
->bi_bdev
= rdev
->bdev
;
4300 align_bi
->bi_flags
&= ~(1 << BIO_SEG_VALID
);
4302 if (!bio_fits_rdev(align_bi
) ||
4303 is_badblock(rdev
, align_bi
->bi_iter
.bi_sector
,
4304 bio_sectors(align_bi
),
4305 &first_bad
, &bad_sectors
)) {
4306 /* too big in some way, or has a known bad block */
4308 rdev_dec_pending(rdev
, mddev
);
4312 /* No reshape active, so we can trust rdev->data_offset */
4313 align_bi
->bi_iter
.bi_sector
+= rdev
->data_offset
;
4315 spin_lock_irq(&conf
->device_lock
);
4316 wait_event_lock_irq(conf
->wait_for_stripe
,
4319 atomic_inc(&conf
->active_aligned_reads
);
4320 spin_unlock_irq(&conf
->device_lock
);
4323 trace_block_bio_remap(bdev_get_queue(align_bi
->bi_bdev
),
4324 align_bi
, disk_devt(mddev
->gendisk
),
4325 raid_bio
->bi_iter
.bi_sector
);
4326 generic_make_request(align_bi
);
4335 /* __get_priority_stripe - get the next stripe to process
4337 * Full stripe writes are allowed to pass preread active stripes up until
4338 * the bypass_threshold is exceeded. In general the bypass_count
4339 * increments when the handle_list is handled before the hold_list; however, it
4340 * will not be incremented when STRIPE_IO_STARTED is sampled set signifying a
4341 * stripe with in flight i/o. The bypass_count will be reset when the
4342 * head of the hold_list has changed, i.e. the head was promoted to the
4345 static struct stripe_head
*__get_priority_stripe(struct r5conf
*conf
, int group
)
4347 struct stripe_head
*sh
= NULL
, *tmp
;
4348 struct list_head
*handle_list
= NULL
;
4349 struct r5worker_group
*wg
= NULL
;
4351 if (conf
->worker_cnt_per_group
== 0) {
4352 handle_list
= &conf
->handle_list
;
4353 } else if (group
!= ANY_GROUP
) {
4354 handle_list
= &conf
->worker_groups
[group
].handle_list
;
4355 wg
= &conf
->worker_groups
[group
];
4358 for (i
= 0; i
< conf
->group_cnt
; i
++) {
4359 handle_list
= &conf
->worker_groups
[i
].handle_list
;
4360 wg
= &conf
->worker_groups
[i
];
4361 if (!list_empty(handle_list
))
4366 pr_debug("%s: handle: %s hold: %s full_writes: %d bypass_count: %d\n",
4368 list_empty(handle_list
) ? "empty" : "busy",
4369 list_empty(&conf
->hold_list
) ? "empty" : "busy",
4370 atomic_read(&conf
->pending_full_writes
), conf
->bypass_count
);
4372 if (!list_empty(handle_list
)) {
4373 sh
= list_entry(handle_list
->next
, typeof(*sh
), lru
);
4375 if (list_empty(&conf
->hold_list
))
4376 conf
->bypass_count
= 0;
4377 else if (!test_bit(STRIPE_IO_STARTED
, &sh
->state
)) {
4378 if (conf
->hold_list
.next
== conf
->last_hold
)
4379 conf
->bypass_count
++;
4381 conf
->last_hold
= conf
->hold_list
.next
;
4382 conf
->bypass_count
-= conf
->bypass_threshold
;
4383 if (conf
->bypass_count
< 0)
4384 conf
->bypass_count
= 0;
4387 } else if (!list_empty(&conf
->hold_list
) &&
4388 ((conf
->bypass_threshold
&&
4389 conf
->bypass_count
> conf
->bypass_threshold
) ||
4390 atomic_read(&conf
->pending_full_writes
) == 0)) {
4392 list_for_each_entry(tmp
, &conf
->hold_list
, lru
) {
4393 if (conf
->worker_cnt_per_group
== 0 ||
4394 group
== ANY_GROUP
||
4395 !cpu_online(tmp
->cpu
) ||
4396 cpu_to_group(tmp
->cpu
) == group
) {
4403 conf
->bypass_count
-= conf
->bypass_threshold
;
4404 if (conf
->bypass_count
< 0)
4405 conf
->bypass_count
= 0;
4417 list_del_init(&sh
->lru
);
4418 BUG_ON(atomic_inc_return(&sh
->count
) != 1);
4422 struct raid5_plug_cb
{
4423 struct blk_plug_cb cb
;
4424 struct list_head list
;
4425 struct list_head temp_inactive_list
[NR_STRIPE_HASH_LOCKS
];
4428 static void raid5_unplug(struct blk_plug_cb
*blk_cb
, bool from_schedule
)
4430 struct raid5_plug_cb
*cb
= container_of(
4431 blk_cb
, struct raid5_plug_cb
, cb
);
4432 struct stripe_head
*sh
;
4433 struct mddev
*mddev
= cb
->cb
.data
;
4434 struct r5conf
*conf
= mddev
->private;
4438 if (cb
->list
.next
&& !list_empty(&cb
->list
)) {
4439 spin_lock_irq(&conf
->device_lock
);
4440 while (!list_empty(&cb
->list
)) {
4441 sh
= list_first_entry(&cb
->list
, struct stripe_head
, lru
);
4442 list_del_init(&sh
->lru
);
4444 * avoid race release_stripe_plug() sees
4445 * STRIPE_ON_UNPLUG_LIST clear but the stripe
4446 * is still in our list
4448 smp_mb__before_atomic();
4449 clear_bit(STRIPE_ON_UNPLUG_LIST
, &sh
->state
);
4451 * STRIPE_ON_RELEASE_LIST could be set here. In that
4452 * case, the count is always > 1 here
4454 hash
= sh
->hash_lock_index
;
4455 __release_stripe(conf
, sh
, &cb
->temp_inactive_list
[hash
]);
4458 spin_unlock_irq(&conf
->device_lock
);
4460 release_inactive_stripe_list(conf
, cb
->temp_inactive_list
,
4461 NR_STRIPE_HASH_LOCKS
);
4463 trace_block_unplug(mddev
->queue
, cnt
, !from_schedule
);
4467 static void release_stripe_plug(struct mddev
*mddev
,
4468 struct stripe_head
*sh
)
4470 struct blk_plug_cb
*blk_cb
= blk_check_plugged(
4471 raid5_unplug
, mddev
,
4472 sizeof(struct raid5_plug_cb
));
4473 struct raid5_plug_cb
*cb
;
4480 cb
= container_of(blk_cb
, struct raid5_plug_cb
, cb
);
4482 if (cb
->list
.next
== NULL
) {
4484 INIT_LIST_HEAD(&cb
->list
);
4485 for (i
= 0; i
< NR_STRIPE_HASH_LOCKS
; i
++)
4486 INIT_LIST_HEAD(cb
->temp_inactive_list
+ i
);
4489 if (!test_and_set_bit(STRIPE_ON_UNPLUG_LIST
, &sh
->state
))
4490 list_add_tail(&sh
->lru
, &cb
->list
);
4495 static void make_discard_request(struct mddev
*mddev
, struct bio
*bi
)
4497 struct r5conf
*conf
= mddev
->private;
4498 sector_t logical_sector
, last_sector
;
4499 struct stripe_head
*sh
;
4503 if (mddev
->reshape_position
!= MaxSector
)
4504 /* Skip discard while reshape is happening */
4507 logical_sector
= bi
->bi_iter
.bi_sector
& ~((sector_t
)STRIPE_SECTORS
-1);
4508 last_sector
= bi
->bi_iter
.bi_sector
+ (bi
->bi_iter
.bi_size
>>9);
4511 bi
->bi_phys_segments
= 1; /* over-loaded to count active stripes */
4513 stripe_sectors
= conf
->chunk_sectors
*
4514 (conf
->raid_disks
- conf
->max_degraded
);
4515 logical_sector
= DIV_ROUND_UP_SECTOR_T(logical_sector
,
4517 sector_div(last_sector
, stripe_sectors
);
4519 logical_sector
*= conf
->chunk_sectors
;
4520 last_sector
*= conf
->chunk_sectors
;
4522 for (; logical_sector
< last_sector
;
4523 logical_sector
+= STRIPE_SECTORS
) {
4527 sh
= get_active_stripe(conf
, logical_sector
, 0, 0, 0);
4528 prepare_to_wait(&conf
->wait_for_overlap
, &w
,
4529 TASK_UNINTERRUPTIBLE
);
4530 set_bit(R5_Overlap
, &sh
->dev
[sh
->pd_idx
].flags
);
4531 if (test_bit(STRIPE_SYNCING
, &sh
->state
)) {
4536 clear_bit(R5_Overlap
, &sh
->dev
[sh
->pd_idx
].flags
);
4537 spin_lock_irq(&sh
->stripe_lock
);
4538 for (d
= 0; d
< conf
->raid_disks
; d
++) {
4539 if (d
== sh
->pd_idx
|| d
== sh
->qd_idx
)
4541 if (sh
->dev
[d
].towrite
|| sh
->dev
[d
].toread
) {
4542 set_bit(R5_Overlap
, &sh
->dev
[d
].flags
);
4543 spin_unlock_irq(&sh
->stripe_lock
);
4549 set_bit(STRIPE_DISCARD
, &sh
->state
);
4550 finish_wait(&conf
->wait_for_overlap
, &w
);
4551 for (d
= 0; d
< conf
->raid_disks
; d
++) {
4552 if (d
== sh
->pd_idx
|| d
== sh
->qd_idx
)
4554 sh
->dev
[d
].towrite
= bi
;
4555 set_bit(R5_OVERWRITE
, &sh
->dev
[d
].flags
);
4556 raid5_inc_bi_active_stripes(bi
);
4558 spin_unlock_irq(&sh
->stripe_lock
);
4559 if (conf
->mddev
->bitmap
) {
4561 d
< conf
->raid_disks
- conf
->max_degraded
;
4563 bitmap_startwrite(mddev
->bitmap
,
4567 sh
->bm_seq
= conf
->seq_flush
+ 1;
4568 set_bit(STRIPE_BIT_DELAY
, &sh
->state
);
4571 set_bit(STRIPE_HANDLE
, &sh
->state
);
4572 clear_bit(STRIPE_DELAYED
, &sh
->state
);
4573 if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
4574 atomic_inc(&conf
->preread_active_stripes
);
4575 release_stripe_plug(mddev
, sh
);
4578 remaining
= raid5_dec_bi_active_stripes(bi
);
4579 if (remaining
== 0) {
4580 md_write_end(mddev
);
4585 static void make_request(struct mddev
*mddev
, struct bio
* bi
)
4587 struct r5conf
*conf
= mddev
->private;
4589 sector_t new_sector
;
4590 sector_t logical_sector
, last_sector
;
4591 struct stripe_head
*sh
;
4592 const int rw
= bio_data_dir(bi
);
4597 if (unlikely(bi
->bi_rw
& REQ_FLUSH
)) {
4598 md_flush_request(mddev
, bi
);
4602 md_write_start(mddev
, bi
);
4605 mddev
->reshape_position
== MaxSector
&&
4606 chunk_aligned_read(mddev
,bi
))
4609 if (unlikely(bi
->bi_rw
& REQ_DISCARD
)) {
4610 make_discard_request(mddev
, bi
);
4614 logical_sector
= bi
->bi_iter
.bi_sector
& ~((sector_t
)STRIPE_SECTORS
-1);
4615 last_sector
= bio_end_sector(bi
);
4617 bi
->bi_phys_segments
= 1; /* over-loaded to count active stripes */
4619 prepare_to_wait(&conf
->wait_for_overlap
, &w
, TASK_UNINTERRUPTIBLE
);
4620 for (;logical_sector
< last_sector
; logical_sector
+= STRIPE_SECTORS
) {
4626 seq
= read_seqcount_begin(&conf
->gen_lock
);
4629 prepare_to_wait(&conf
->wait_for_overlap
, &w
,
4630 TASK_UNINTERRUPTIBLE
);
4631 if (unlikely(conf
->reshape_progress
!= MaxSector
)) {
4632 /* spinlock is needed as reshape_progress may be
4633 * 64bit on a 32bit platform, and so it might be
4634 * possible to see a half-updated value
4635 * Of course reshape_progress could change after
4636 * the lock is dropped, so once we get a reference
4637 * to the stripe that we think it is, we will have
4640 spin_lock_irq(&conf
->device_lock
);
4641 if (mddev
->reshape_backwards
4642 ? logical_sector
< conf
->reshape_progress
4643 : logical_sector
>= conf
->reshape_progress
) {
4646 if (mddev
->reshape_backwards
4647 ? logical_sector
< conf
->reshape_safe
4648 : logical_sector
>= conf
->reshape_safe
) {
4649 spin_unlock_irq(&conf
->device_lock
);
4655 spin_unlock_irq(&conf
->device_lock
);
4658 new_sector
= raid5_compute_sector(conf
, logical_sector
,
4661 pr_debug("raid456: make_request, sector %llu logical %llu\n",
4662 (unsigned long long)new_sector
,
4663 (unsigned long long)logical_sector
);
4665 sh
= get_active_stripe(conf
, new_sector
, previous
,
4666 (bi
->bi_rw
&RWA_MASK
), 0);
4668 if (unlikely(previous
)) {
4669 /* expansion might have moved on while waiting for a
4670 * stripe, so we must do the range check again.
4671 * Expansion could still move past after this
4672 * test, but as we are holding a reference to
4673 * 'sh', we know that if that happens,
4674 * STRIPE_EXPANDING will get set and the expansion
4675 * won't proceed until we finish with the stripe.
4678 spin_lock_irq(&conf
->device_lock
);
4679 if (mddev
->reshape_backwards
4680 ? logical_sector
>= conf
->reshape_progress
4681 : logical_sector
< conf
->reshape_progress
)
4682 /* mismatch, need to try again */
4684 spin_unlock_irq(&conf
->device_lock
);
4692 if (read_seqcount_retry(&conf
->gen_lock
, seq
)) {
4693 /* Might have got the wrong stripe_head
4701 logical_sector
>= mddev
->suspend_lo
&&
4702 logical_sector
< mddev
->suspend_hi
) {
4704 /* As the suspend_* range is controlled by
4705 * userspace, we want an interruptible
4708 flush_signals(current
);
4709 prepare_to_wait(&conf
->wait_for_overlap
,
4710 &w
, TASK_INTERRUPTIBLE
);
4711 if (logical_sector
>= mddev
->suspend_lo
&&
4712 logical_sector
< mddev
->suspend_hi
) {
4719 if (test_bit(STRIPE_EXPANDING
, &sh
->state
) ||
4720 !add_stripe_bio(sh
, bi
, dd_idx
, rw
)) {
4721 /* Stripe is busy expanding or
4722 * add failed due to overlap. Flush everything
4725 md_wakeup_thread(mddev
->thread
);
4731 set_bit(STRIPE_HANDLE
, &sh
->state
);
4732 clear_bit(STRIPE_DELAYED
, &sh
->state
);
4733 if ((bi
->bi_rw
& REQ_SYNC
) &&
4734 !test_and_set_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
4735 atomic_inc(&conf
->preread_active_stripes
);
4736 release_stripe_plug(mddev
, sh
);
4738 /* cannot get stripe for read-ahead, just give-up */
4739 clear_bit(BIO_UPTODATE
, &bi
->bi_flags
);
4743 finish_wait(&conf
->wait_for_overlap
, &w
);
4745 remaining
= raid5_dec_bi_active_stripes(bi
);
4746 if (remaining
== 0) {
4749 md_write_end(mddev
);
4751 trace_block_bio_complete(bdev_get_queue(bi
->bi_bdev
),
4757 static sector_t
raid5_size(struct mddev
*mddev
, sector_t sectors
, int raid_disks
);
4759 static sector_t
reshape_request(struct mddev
*mddev
, sector_t sector_nr
, int *skipped
)
4761 /* reshaping is quite different to recovery/resync so it is
4762 * handled quite separately ... here.
4764 * On each call to sync_request, we gather one chunk worth of
4765 * destination stripes and flag them as expanding.
4766 * Then we find all the source stripes and request reads.
4767 * As the reads complete, handle_stripe will copy the data
4768 * into the destination stripe and release that stripe.
4770 struct r5conf
*conf
= mddev
->private;
4771 struct stripe_head
*sh
;
4772 sector_t first_sector
, last_sector
;
4773 int raid_disks
= conf
->previous_raid_disks
;
4774 int data_disks
= raid_disks
- conf
->max_degraded
;
4775 int new_data_disks
= conf
->raid_disks
- conf
->max_degraded
;
4778 sector_t writepos
, readpos
, safepos
;
4779 sector_t stripe_addr
;
4780 int reshape_sectors
;
4781 struct list_head stripes
;
4783 if (sector_nr
== 0) {
4784 /* If restarting in the middle, skip the initial sectors */
4785 if (mddev
->reshape_backwards
&&
4786 conf
->reshape_progress
< raid5_size(mddev
, 0, 0)) {
4787 sector_nr
= raid5_size(mddev
, 0, 0)
4788 - conf
->reshape_progress
;
4789 } else if (!mddev
->reshape_backwards
&&
4790 conf
->reshape_progress
> 0)
4791 sector_nr
= conf
->reshape_progress
;
4792 sector_div(sector_nr
, new_data_disks
);
4794 mddev
->curr_resync_completed
= sector_nr
;
4795 sysfs_notify(&mddev
->kobj
, NULL
, "sync_completed");
4801 /* We need to process a full chunk at a time.
4802 * If old and new chunk sizes differ, we need to process the
4805 if (mddev
->new_chunk_sectors
> mddev
->chunk_sectors
)
4806 reshape_sectors
= mddev
->new_chunk_sectors
;
4808 reshape_sectors
= mddev
->chunk_sectors
;
4810 /* We update the metadata at least every 10 seconds, or when
4811 * the data about to be copied would over-write the source of
4812 * the data at the front of the range. i.e. one new_stripe
4813 * along from reshape_progress new_maps to after where
4814 * reshape_safe old_maps to
4816 writepos
= conf
->reshape_progress
;
4817 sector_div(writepos
, new_data_disks
);
4818 readpos
= conf
->reshape_progress
;
4819 sector_div(readpos
, data_disks
);
4820 safepos
= conf
->reshape_safe
;
4821 sector_div(safepos
, data_disks
);
4822 if (mddev
->reshape_backwards
) {
4823 writepos
-= min_t(sector_t
, reshape_sectors
, writepos
);
4824 readpos
+= reshape_sectors
;
4825 safepos
+= reshape_sectors
;
4827 writepos
+= reshape_sectors
;
4828 readpos
-= min_t(sector_t
, reshape_sectors
, readpos
);
4829 safepos
-= min_t(sector_t
, reshape_sectors
, safepos
);
4832 /* Having calculated the 'writepos' possibly use it
4833 * to set 'stripe_addr' which is where we will write to.
4835 if (mddev
->reshape_backwards
) {
4836 BUG_ON(conf
->reshape_progress
== 0);
4837 stripe_addr
= writepos
;
4838 BUG_ON((mddev
->dev_sectors
&
4839 ~((sector_t
)reshape_sectors
- 1))
4840 - reshape_sectors
- stripe_addr
4843 BUG_ON(writepos
!= sector_nr
+ reshape_sectors
);
4844 stripe_addr
= sector_nr
;
4847 /* 'writepos' is the most advanced device address we might write.
4848 * 'readpos' is the least advanced device address we might read.
4849 * 'safepos' is the least address recorded in the metadata as having
4851 * If there is a min_offset_diff, these are adjusted either by
4852 * increasing the safepos/readpos if diff is negative, or
4853 * increasing writepos if diff is positive.
4854 * If 'readpos' is then behind 'writepos', there is no way that we can
4855 * ensure safety in the face of a crash - that must be done by userspace
4856 * making a backup of the data. So in that case there is no particular
4857 * rush to update metadata.
4858 * Otherwise if 'safepos' is behind 'writepos', then we really need to
4859 * update the metadata to advance 'safepos' to match 'readpos' so that
4860 * we can be safe in the event of a crash.
4861 * So we insist on updating metadata if safepos is behind writepos and
4862 * readpos is beyond writepos.
4863 * In any case, update the metadata every 10 seconds.
4864 * Maybe that number should be configurable, but I'm not sure it is
4865 * worth it.... maybe it could be a multiple of safemode_delay???
4867 if (conf
->min_offset_diff
< 0) {
4868 safepos
+= -conf
->min_offset_diff
;
4869 readpos
+= -conf
->min_offset_diff
;
4871 writepos
+= conf
->min_offset_diff
;
4873 if ((mddev
->reshape_backwards
4874 ? (safepos
> writepos
&& readpos
< writepos
)
4875 : (safepos
< writepos
&& readpos
> writepos
)) ||
4876 time_after(jiffies
, conf
->reshape_checkpoint
+ 10*HZ
)) {
4877 /* Cannot proceed until we've updated the superblock... */
4878 wait_event(conf
->wait_for_overlap
,
4879 atomic_read(&conf
->reshape_stripes
)==0
4880 || test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
));
4881 if (atomic_read(&conf
->reshape_stripes
) != 0)
4883 mddev
->reshape_position
= conf
->reshape_progress
;
4884 mddev
->curr_resync_completed
= sector_nr
;
4885 conf
->reshape_checkpoint
= jiffies
;
4886 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
4887 md_wakeup_thread(mddev
->thread
);
4888 wait_event(mddev
->sb_wait
, mddev
->flags
== 0 ||
4889 test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
));
4890 if (test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
))
4892 spin_lock_irq(&conf
->device_lock
);
4893 conf
->reshape_safe
= mddev
->reshape_position
;
4894 spin_unlock_irq(&conf
->device_lock
);
4895 wake_up(&conf
->wait_for_overlap
);
4896 sysfs_notify(&mddev
->kobj
, NULL
, "sync_completed");
4899 INIT_LIST_HEAD(&stripes
);
4900 for (i
= 0; i
< reshape_sectors
; i
+= STRIPE_SECTORS
) {
4902 int skipped_disk
= 0;
4903 sh
= get_active_stripe(conf
, stripe_addr
+i
, 0, 0, 1);
4904 set_bit(STRIPE_EXPANDING
, &sh
->state
);
4905 atomic_inc(&conf
->reshape_stripes
);
4906 /* If any of this stripe is beyond the end of the old
4907 * array, then we need to zero those blocks
4909 for (j
=sh
->disks
; j
--;) {
4911 if (j
== sh
->pd_idx
)
4913 if (conf
->level
== 6 &&
4916 s
= compute_blocknr(sh
, j
, 0);
4917 if (s
< raid5_size(mddev
, 0, 0)) {
4921 memset(page_address(sh
->dev
[j
].page
), 0, STRIPE_SIZE
);
4922 set_bit(R5_Expanded
, &sh
->dev
[j
].flags
);
4923 set_bit(R5_UPTODATE
, &sh
->dev
[j
].flags
);
4925 if (!skipped_disk
) {
4926 set_bit(STRIPE_EXPAND_READY
, &sh
->state
);
4927 set_bit(STRIPE_HANDLE
, &sh
->state
);
4929 list_add(&sh
->lru
, &stripes
);
4931 spin_lock_irq(&conf
->device_lock
);
4932 if (mddev
->reshape_backwards
)
4933 conf
->reshape_progress
-= reshape_sectors
* new_data_disks
;
4935 conf
->reshape_progress
+= reshape_sectors
* new_data_disks
;
4936 spin_unlock_irq(&conf
->device_lock
);
4937 /* Ok, those stripe are ready. We can start scheduling
4938 * reads on the source stripes.
4939 * The source stripes are determined by mapping the first and last
4940 * block on the destination stripes.
4943 raid5_compute_sector(conf
, stripe_addr
*(new_data_disks
),
4946 raid5_compute_sector(conf
, ((stripe_addr
+reshape_sectors
)
4947 * new_data_disks
- 1),
4949 if (last_sector
>= mddev
->dev_sectors
)
4950 last_sector
= mddev
->dev_sectors
- 1;
4951 while (first_sector
<= last_sector
) {
4952 sh
= get_active_stripe(conf
, first_sector
, 1, 0, 1);
4953 set_bit(STRIPE_EXPAND_SOURCE
, &sh
->state
);
4954 set_bit(STRIPE_HANDLE
, &sh
->state
);
4956 first_sector
+= STRIPE_SECTORS
;
4958 /* Now that the sources are clearly marked, we can release
4959 * the destination stripes
4961 while (!list_empty(&stripes
)) {
4962 sh
= list_entry(stripes
.next
, struct stripe_head
, lru
);
4963 list_del_init(&sh
->lru
);
4966 /* If this takes us to the resync_max point where we have to pause,
4967 * then we need to write out the superblock.
4969 sector_nr
+= reshape_sectors
;
4970 if ((sector_nr
- mddev
->curr_resync_completed
) * 2
4971 >= mddev
->resync_max
- mddev
->curr_resync_completed
) {
4972 /* Cannot proceed until we've updated the superblock... */
4973 wait_event(conf
->wait_for_overlap
,
4974 atomic_read(&conf
->reshape_stripes
) == 0
4975 || test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
));
4976 if (atomic_read(&conf
->reshape_stripes
) != 0)
4978 mddev
->reshape_position
= conf
->reshape_progress
;
4979 mddev
->curr_resync_completed
= sector_nr
;
4980 conf
->reshape_checkpoint
= jiffies
;
4981 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
4982 md_wakeup_thread(mddev
->thread
);
4983 wait_event(mddev
->sb_wait
,
4984 !test_bit(MD_CHANGE_DEVS
, &mddev
->flags
)
4985 || test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
));
4986 if (test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
))
4988 spin_lock_irq(&conf
->device_lock
);
4989 conf
->reshape_safe
= mddev
->reshape_position
;
4990 spin_unlock_irq(&conf
->device_lock
);
4991 wake_up(&conf
->wait_for_overlap
);
4992 sysfs_notify(&mddev
->kobj
, NULL
, "sync_completed");
4995 return reshape_sectors
;
4998 /* FIXME go_faster isn't used */
4999 static inline sector_t
sync_request(struct mddev
*mddev
, sector_t sector_nr
, int *skipped
, int go_faster
)
5001 struct r5conf
*conf
= mddev
->private;
5002 struct stripe_head
*sh
;
5003 sector_t max_sector
= mddev
->dev_sectors
;
5004 sector_t sync_blocks
;
5005 int still_degraded
= 0;
5008 if (sector_nr
>= max_sector
) {
5009 /* just being told to finish up .. nothing much to do */
5011 if (test_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
)) {
5016 if (mddev
->curr_resync
< max_sector
) /* aborted */
5017 bitmap_end_sync(mddev
->bitmap
, mddev
->curr_resync
,
5019 else /* completed sync */
5021 bitmap_close_sync(mddev
->bitmap
);
5026 /* Allow raid5_quiesce to complete */
5027 wait_event(conf
->wait_for_overlap
, conf
->quiesce
!= 2);
5029 if (test_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
))
5030 return reshape_request(mddev
, sector_nr
, skipped
);
5032 /* No need to check resync_max as we never do more than one
5033 * stripe, and as resync_max will always be on a chunk boundary,
5034 * if the check in md_do_sync didn't fire, there is no chance
5035 * of overstepping resync_max here
5038 /* if there is too many failed drives and we are trying
5039 * to resync, then assert that we are finished, because there is
5040 * nothing we can do.
5042 if (mddev
->degraded
>= conf
->max_degraded
&&
5043 test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
)) {
5044 sector_t rv
= mddev
->dev_sectors
- sector_nr
;
5048 if (!test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
) &&
5050 !bitmap_start_sync(mddev
->bitmap
, sector_nr
, &sync_blocks
, 1) &&
5051 sync_blocks
>= STRIPE_SECTORS
) {
5052 /* we can skip this block, and probably more */
5053 sync_blocks
/= STRIPE_SECTORS
;
5055 return sync_blocks
* STRIPE_SECTORS
; /* keep things rounded to whole stripes */
5058 bitmap_cond_end_sync(mddev
->bitmap
, sector_nr
);
5060 sh
= get_active_stripe(conf
, sector_nr
, 0, 1, 0);
5062 sh
= get_active_stripe(conf
, sector_nr
, 0, 0, 0);
5063 /* make sure we don't swamp the stripe cache if someone else
5064 * is trying to get access
5066 schedule_timeout_uninterruptible(1);
5068 /* Need to check if array will still be degraded after recovery/resync
5069 * We don't need to check the 'failed' flag as when that gets set,
5072 for (i
= 0; i
< conf
->raid_disks
; i
++)
5073 if (conf
->disks
[i
].rdev
== NULL
)
5076 bitmap_start_sync(mddev
->bitmap
, sector_nr
, &sync_blocks
, still_degraded
);
5078 set_bit(STRIPE_SYNC_REQUESTED
, &sh
->state
);
5079 set_bit(STRIPE_HANDLE
, &sh
->state
);
5083 return STRIPE_SECTORS
;
5086 static int retry_aligned_read(struct r5conf
*conf
, struct bio
*raid_bio
)
5088 /* We may not be able to submit a whole bio at once as there
5089 * may not be enough stripe_heads available.
5090 * We cannot pre-allocate enough stripe_heads as we may need
5091 * more than exist in the cache (if we allow ever large chunks).
5092 * So we do one stripe head at a time and record in
5093 * ->bi_hw_segments how many have been done.
5095 * We *know* that this entire raid_bio is in one chunk, so
5096 * it will be only one 'dd_idx' and only need one call to raid5_compute_sector.
5098 struct stripe_head
*sh
;
5100 sector_t sector
, logical_sector
, last_sector
;
5105 logical_sector
= raid_bio
->bi_iter
.bi_sector
&
5106 ~((sector_t
)STRIPE_SECTORS
-1);
5107 sector
= raid5_compute_sector(conf
, logical_sector
,
5109 last_sector
= bio_end_sector(raid_bio
);
5111 for (; logical_sector
< last_sector
;
5112 logical_sector
+= STRIPE_SECTORS
,
5113 sector
+= STRIPE_SECTORS
,
5116 if (scnt
< raid5_bi_processed_stripes(raid_bio
))
5117 /* already done this stripe */
5120 sh
= get_active_stripe(conf
, sector
, 0, 1, 1);
5123 /* failed to get a stripe - must wait */
5124 raid5_set_bi_processed_stripes(raid_bio
, scnt
);
5125 conf
->retry_read_aligned
= raid_bio
;
5129 if (!add_stripe_bio(sh
, raid_bio
, dd_idx
, 0)) {
5131 raid5_set_bi_processed_stripes(raid_bio
, scnt
);
5132 conf
->retry_read_aligned
= raid_bio
;
5136 set_bit(R5_ReadNoMerge
, &sh
->dev
[dd_idx
].flags
);
5141 remaining
= raid5_dec_bi_active_stripes(raid_bio
);
5142 if (remaining
== 0) {
5143 trace_block_bio_complete(bdev_get_queue(raid_bio
->bi_bdev
),
5145 bio_endio(raid_bio
, 0);
5147 if (atomic_dec_and_test(&conf
->active_aligned_reads
))
5148 wake_up(&conf
->wait_for_stripe
);
5152 static int handle_active_stripes(struct r5conf
*conf
, int group
,
5153 struct r5worker
*worker
,
5154 struct list_head
*temp_inactive_list
)
5156 struct stripe_head
*batch
[MAX_STRIPE_BATCH
], *sh
;
5157 int i
, batch_size
= 0, hash
;
5158 bool release_inactive
= false;
5160 while (batch_size
< MAX_STRIPE_BATCH
&&
5161 (sh
= __get_priority_stripe(conf
, group
)) != NULL
)
5162 batch
[batch_size
++] = sh
;
5164 if (batch_size
== 0) {
5165 for (i
= 0; i
< NR_STRIPE_HASH_LOCKS
; i
++)
5166 if (!list_empty(temp_inactive_list
+ i
))
5168 if (i
== NR_STRIPE_HASH_LOCKS
)
5170 release_inactive
= true;
5172 spin_unlock_irq(&conf
->device_lock
);
5174 release_inactive_stripe_list(conf
, temp_inactive_list
,
5175 NR_STRIPE_HASH_LOCKS
);
5177 if (release_inactive
) {
5178 spin_lock_irq(&conf
->device_lock
);
5182 for (i
= 0; i
< batch_size
; i
++)
5183 handle_stripe(batch
[i
]);
5187 spin_lock_irq(&conf
->device_lock
);
5188 for (i
= 0; i
< batch_size
; i
++) {
5189 hash
= batch
[i
]->hash_lock_index
;
5190 __release_stripe(conf
, batch
[i
], &temp_inactive_list
[hash
]);
5195 static void raid5_do_work(struct work_struct
*work
)
5197 struct r5worker
*worker
= container_of(work
, struct r5worker
, work
);
5198 struct r5worker_group
*group
= worker
->group
;
5199 struct r5conf
*conf
= group
->conf
;
5200 int group_id
= group
- conf
->worker_groups
;
5202 struct blk_plug plug
;
5204 pr_debug("+++ raid5worker active\n");
5206 blk_start_plug(&plug
);
5208 spin_lock_irq(&conf
->device_lock
);
5210 int batch_size
, released
;
5212 released
= release_stripe_list(conf
, worker
->temp_inactive_list
);
5214 batch_size
= handle_active_stripes(conf
, group_id
, worker
,
5215 worker
->temp_inactive_list
);
5216 worker
->working
= false;
5217 if (!batch_size
&& !released
)
5219 handled
+= batch_size
;
5221 pr_debug("%d stripes handled\n", handled
);
5223 spin_unlock_irq(&conf
->device_lock
);
5224 blk_finish_plug(&plug
);
5226 pr_debug("--- raid5worker inactive\n");
5230 * This is our raid5 kernel thread.
5232 * We scan the hash table for stripes which can be handled now.
5233 * During the scan, completed stripes are saved for us by the interrupt
5234 * handler, so that they will not have to wait for our next wakeup.
5236 static void raid5d(struct md_thread
*thread
)
5238 struct mddev
*mddev
= thread
->mddev
;
5239 struct r5conf
*conf
= mddev
->private;
5241 struct blk_plug plug
;
5243 pr_debug("+++ raid5d active\n");
5245 md_check_recovery(mddev
);
5247 blk_start_plug(&plug
);
5249 spin_lock_irq(&conf
->device_lock
);
5252 int batch_size
, released
;
5254 released
= release_stripe_list(conf
, conf
->temp_inactive_list
);
5257 !list_empty(&conf
->bitmap_list
)) {
5258 /* Now is a good time to flush some bitmap updates */
5260 spin_unlock_irq(&conf
->device_lock
);
5261 bitmap_unplug(mddev
->bitmap
);
5262 spin_lock_irq(&conf
->device_lock
);
5263 conf
->seq_write
= conf
->seq_flush
;
5264 activate_bit_delay(conf
, conf
->temp_inactive_list
);
5266 raid5_activate_delayed(conf
);
5268 while ((bio
= remove_bio_from_retry(conf
))) {
5270 spin_unlock_irq(&conf
->device_lock
);
5271 ok
= retry_aligned_read(conf
, bio
);
5272 spin_lock_irq(&conf
->device_lock
);
5278 batch_size
= handle_active_stripes(conf
, ANY_GROUP
, NULL
,
5279 conf
->temp_inactive_list
);
5280 if (!batch_size
&& !released
)
5282 handled
+= batch_size
;
5284 if (mddev
->flags
& ~(1<<MD_CHANGE_PENDING
)) {
5285 spin_unlock_irq(&conf
->device_lock
);
5286 md_check_recovery(mddev
);
5287 spin_lock_irq(&conf
->device_lock
);
5290 pr_debug("%d stripes handled\n", handled
);
5292 spin_unlock_irq(&conf
->device_lock
);
5294 async_tx_issue_pending_all();
5295 blk_finish_plug(&plug
);
5297 pr_debug("--- raid5d inactive\n");
5301 raid5_show_stripe_cache_size(struct mddev
*mddev
, char *page
)
5303 struct r5conf
*conf
= mddev
->private;
5305 return sprintf(page
, "%d\n", conf
->max_nr_stripes
);
5311 raid5_set_cache_size(struct mddev
*mddev
, int size
)
5313 struct r5conf
*conf
= mddev
->private;
5317 if (size
<= 16 || size
> 32768)
5319 hash
= (conf
->max_nr_stripes
- 1) % NR_STRIPE_HASH_LOCKS
;
5320 while (size
< conf
->max_nr_stripes
) {
5321 if (drop_one_stripe(conf
, hash
))
5322 conf
->max_nr_stripes
--;
5327 hash
= NR_STRIPE_HASH_LOCKS
- 1;
5329 err
= md_allow_write(mddev
);
5332 hash
= conf
->max_nr_stripes
% NR_STRIPE_HASH_LOCKS
;
5333 while (size
> conf
->max_nr_stripes
) {
5334 if (grow_one_stripe(conf
, hash
))
5335 conf
->max_nr_stripes
++;
5337 hash
= (hash
+ 1) % NR_STRIPE_HASH_LOCKS
;
5341 EXPORT_SYMBOL(raid5_set_cache_size
);
5344 raid5_store_stripe_cache_size(struct mddev
*mddev
, const char *page
, size_t len
)
5346 struct r5conf
*conf
= mddev
->private;
5350 if (len
>= PAGE_SIZE
)
5355 if (kstrtoul(page
, 10, &new))
5357 err
= raid5_set_cache_size(mddev
, new);
5363 static struct md_sysfs_entry
5364 raid5_stripecache_size
= __ATTR(stripe_cache_size
, S_IRUGO
| S_IWUSR
,
5365 raid5_show_stripe_cache_size
,
5366 raid5_store_stripe_cache_size
);
5369 raid5_show_preread_threshold(struct mddev
*mddev
, char *page
)
5371 struct r5conf
*conf
= mddev
->private;
5373 return sprintf(page
, "%d\n", conf
->bypass_threshold
);
5379 raid5_store_preread_threshold(struct mddev
*mddev
, const char *page
, size_t len
)
5381 struct r5conf
*conf
= mddev
->private;
5383 if (len
>= PAGE_SIZE
)
5388 if (kstrtoul(page
, 10, &new))
5390 if (new > conf
->max_nr_stripes
)
5392 conf
->bypass_threshold
= new;
5396 static struct md_sysfs_entry
5397 raid5_preread_bypass_threshold
= __ATTR(preread_bypass_threshold
,
5399 raid5_show_preread_threshold
,
5400 raid5_store_preread_threshold
);
5403 raid5_show_skip_copy(struct mddev
*mddev
, char *page
)
5405 struct r5conf
*conf
= mddev
->private;
5407 return sprintf(page
, "%d\n", conf
->skip_copy
);
5413 raid5_store_skip_copy(struct mddev
*mddev
, const char *page
, size_t len
)
5415 struct r5conf
*conf
= mddev
->private;
5417 if (len
>= PAGE_SIZE
)
5422 if (kstrtoul(page
, 10, &new))
5425 if (new == conf
->skip_copy
)
5428 mddev_suspend(mddev
);
5429 conf
->skip_copy
= new;
5431 mddev
->queue
->backing_dev_info
.capabilities
|=
5432 BDI_CAP_STABLE_WRITES
;
5434 mddev
->queue
->backing_dev_info
.capabilities
&=
5435 ~BDI_CAP_STABLE_WRITES
;
5436 mddev_resume(mddev
);
5440 static struct md_sysfs_entry
5441 raid5_skip_copy
= __ATTR(skip_copy
, S_IRUGO
| S_IWUSR
,
5442 raid5_show_skip_copy
,
5443 raid5_store_skip_copy
);
5447 stripe_cache_active_show(struct mddev
*mddev
, char *page
)
5449 struct r5conf
*conf
= mddev
->private;
5451 return sprintf(page
, "%d\n", atomic_read(&conf
->active_stripes
));
5456 static struct md_sysfs_entry
5457 raid5_stripecache_active
= __ATTR_RO(stripe_cache_active
);
5460 raid5_show_group_thread_cnt(struct mddev
*mddev
, char *page
)
5462 struct r5conf
*conf
= mddev
->private;
5464 return sprintf(page
, "%d\n", conf
->worker_cnt_per_group
);
5469 static int alloc_thread_groups(struct r5conf
*conf
, int cnt
,
5471 int *worker_cnt_per_group
,
5472 struct r5worker_group
**worker_groups
);
5474 raid5_store_group_thread_cnt(struct mddev
*mddev
, const char *page
, size_t len
)
5476 struct r5conf
*conf
= mddev
->private;
5479 struct r5worker_group
*new_groups
, *old_groups
;
5480 int group_cnt
, worker_cnt_per_group
;
5482 if (len
>= PAGE_SIZE
)
5487 if (kstrtoul(page
, 10, &new))
5490 if (new == conf
->worker_cnt_per_group
)
5493 mddev_suspend(mddev
);
5495 old_groups
= conf
->worker_groups
;
5497 flush_workqueue(raid5_wq
);
5499 err
= alloc_thread_groups(conf
, new,
5500 &group_cnt
, &worker_cnt_per_group
,
5503 spin_lock_irq(&conf
->device_lock
);
5504 conf
->group_cnt
= group_cnt
;
5505 conf
->worker_cnt_per_group
= worker_cnt_per_group
;
5506 conf
->worker_groups
= new_groups
;
5507 spin_unlock_irq(&conf
->device_lock
);
5510 kfree(old_groups
[0].workers
);
5514 mddev_resume(mddev
);
5521 static struct md_sysfs_entry
5522 raid5_group_thread_cnt
= __ATTR(group_thread_cnt
, S_IRUGO
| S_IWUSR
,
5523 raid5_show_group_thread_cnt
,
5524 raid5_store_group_thread_cnt
);
5526 static struct attribute
*raid5_attrs
[] = {
5527 &raid5_stripecache_size
.attr
,
5528 &raid5_stripecache_active
.attr
,
5529 &raid5_preread_bypass_threshold
.attr
,
5530 &raid5_group_thread_cnt
.attr
,
5531 &raid5_skip_copy
.attr
,
5534 static struct attribute_group raid5_attrs_group
= {
5536 .attrs
= raid5_attrs
,
5539 static int alloc_thread_groups(struct r5conf
*conf
, int cnt
,
5541 int *worker_cnt_per_group
,
5542 struct r5worker_group
**worker_groups
)
5546 struct r5worker
*workers
;
5548 *worker_cnt_per_group
= cnt
;
5551 *worker_groups
= NULL
;
5554 *group_cnt
= num_possible_nodes();
5555 size
= sizeof(struct r5worker
) * cnt
;
5556 workers
= kzalloc(size
* *group_cnt
, GFP_NOIO
);
5557 *worker_groups
= kzalloc(sizeof(struct r5worker_group
) *
5558 *group_cnt
, GFP_NOIO
);
5559 if (!*worker_groups
|| !workers
) {
5561 kfree(*worker_groups
);
5565 for (i
= 0; i
< *group_cnt
; i
++) {
5566 struct r5worker_group
*group
;
5568 group
= &(*worker_groups
)[i
];
5569 INIT_LIST_HEAD(&group
->handle_list
);
5571 group
->workers
= workers
+ i
* cnt
;
5573 for (j
= 0; j
< cnt
; j
++) {
5574 struct r5worker
*worker
= group
->workers
+ j
;
5575 worker
->group
= group
;
5576 INIT_WORK(&worker
->work
, raid5_do_work
);
5578 for (k
= 0; k
< NR_STRIPE_HASH_LOCKS
; k
++)
5579 INIT_LIST_HEAD(worker
->temp_inactive_list
+ k
);
5586 static void free_thread_groups(struct r5conf
*conf
)
5588 if (conf
->worker_groups
)
5589 kfree(conf
->worker_groups
[0].workers
);
5590 kfree(conf
->worker_groups
);
5591 conf
->worker_groups
= NULL
;
5595 raid5_size(struct mddev
*mddev
, sector_t sectors
, int raid_disks
)
5597 struct r5conf
*conf
= mddev
->private;
5600 sectors
= mddev
->dev_sectors
;
5602 /* size is defined by the smallest of previous and new size */
5603 raid_disks
= min(conf
->raid_disks
, conf
->previous_raid_disks
);
5605 sectors
&= ~((sector_t
)mddev
->chunk_sectors
- 1);
5606 sectors
&= ~((sector_t
)mddev
->new_chunk_sectors
- 1);
5607 return sectors
* (raid_disks
- conf
->max_degraded
);
5610 static void free_scratch_buffer(struct r5conf
*conf
, struct raid5_percpu
*percpu
)
5612 safe_put_page(percpu
->spare_page
);
5613 kfree(percpu
->scribble
);
5614 percpu
->spare_page
= NULL
;
5615 percpu
->scribble
= NULL
;
5618 static int alloc_scratch_buffer(struct r5conf
*conf
, struct raid5_percpu
*percpu
)
5620 if (conf
->level
== 6 && !percpu
->spare_page
)
5621 percpu
->spare_page
= alloc_page(GFP_KERNEL
);
5622 if (!percpu
->scribble
)
5623 percpu
->scribble
= kmalloc(conf
->scribble_len
, GFP_KERNEL
);
5625 if (!percpu
->scribble
|| (conf
->level
== 6 && !percpu
->spare_page
)) {
5626 free_scratch_buffer(conf
, percpu
);
5633 static void raid5_free_percpu(struct r5conf
*conf
)
5640 #ifdef CONFIG_HOTPLUG_CPU
5641 unregister_cpu_notifier(&conf
->cpu_notify
);
5645 for_each_possible_cpu(cpu
)
5646 free_scratch_buffer(conf
, per_cpu_ptr(conf
->percpu
, cpu
));
5649 free_percpu(conf
->percpu
);
5652 static void free_conf(struct r5conf
*conf
)
5654 free_thread_groups(conf
);
5655 shrink_stripes(conf
);
5656 raid5_free_percpu(conf
);
5658 kfree(conf
->stripe_hashtbl
);
5662 #ifdef CONFIG_HOTPLUG_CPU
5663 static int raid456_cpu_notify(struct notifier_block
*nfb
, unsigned long action
,
5666 struct r5conf
*conf
= container_of(nfb
, struct r5conf
, cpu_notify
);
5667 long cpu
= (long)hcpu
;
5668 struct raid5_percpu
*percpu
= per_cpu_ptr(conf
->percpu
, cpu
);
5671 case CPU_UP_PREPARE
:
5672 case CPU_UP_PREPARE_FROZEN
:
5673 if (alloc_scratch_buffer(conf
, percpu
)) {
5674 pr_err("%s: failed memory allocation for cpu%ld\n",
5676 return notifier_from_errno(-ENOMEM
);
5680 case CPU_DEAD_FROZEN
:
5681 free_scratch_buffer(conf
, per_cpu_ptr(conf
->percpu
, cpu
));
5690 static int raid5_alloc_percpu(struct r5conf
*conf
)
5695 conf
->percpu
= alloc_percpu(struct raid5_percpu
);
5699 #ifdef CONFIG_HOTPLUG_CPU
5700 conf
->cpu_notify
.notifier_call
= raid456_cpu_notify
;
5701 conf
->cpu_notify
.priority
= 0;
5702 err
= register_cpu_notifier(&conf
->cpu_notify
);
5708 for_each_present_cpu(cpu
) {
5709 err
= alloc_scratch_buffer(conf
, per_cpu_ptr(conf
->percpu
, cpu
));
5711 pr_err("%s: failed memory allocation for cpu%ld\n",
5721 static struct r5conf
*setup_conf(struct mddev
*mddev
)
5723 struct r5conf
*conf
;
5724 int raid_disk
, memory
, max_disks
;
5725 struct md_rdev
*rdev
;
5726 struct disk_info
*disk
;
5729 int group_cnt
, worker_cnt_per_group
;
5730 struct r5worker_group
*new_group
;
5732 if (mddev
->new_level
!= 5
5733 && mddev
->new_level
!= 4
5734 && mddev
->new_level
!= 6) {
5735 printk(KERN_ERR
"md/raid:%s: raid level not set to 4/5/6 (%d)\n",
5736 mdname(mddev
), mddev
->new_level
);
5737 return ERR_PTR(-EIO
);
5739 if ((mddev
->new_level
== 5
5740 && !algorithm_valid_raid5(mddev
->new_layout
)) ||
5741 (mddev
->new_level
== 6
5742 && !algorithm_valid_raid6(mddev
->new_layout
))) {
5743 printk(KERN_ERR
"md/raid:%s: layout %d not supported\n",
5744 mdname(mddev
), mddev
->new_layout
);
5745 return ERR_PTR(-EIO
);
5747 if (mddev
->new_level
== 6 && mddev
->raid_disks
< 4) {
5748 printk(KERN_ERR
"md/raid:%s: not enough configured devices (%d, minimum 4)\n",
5749 mdname(mddev
), mddev
->raid_disks
);
5750 return ERR_PTR(-EINVAL
);
5753 if (!mddev
->new_chunk_sectors
||
5754 (mddev
->new_chunk_sectors
<< 9) % PAGE_SIZE
||
5755 !is_power_of_2(mddev
->new_chunk_sectors
)) {
5756 printk(KERN_ERR
"md/raid:%s: invalid chunk size %d\n",
5757 mdname(mddev
), mddev
->new_chunk_sectors
<< 9);
5758 return ERR_PTR(-EINVAL
);
5761 conf
= kzalloc(sizeof(struct r5conf
), GFP_KERNEL
);
5764 /* Don't enable multi-threading by default*/
5765 if (!alloc_thread_groups(conf
, 0, &group_cnt
, &worker_cnt_per_group
,
5767 conf
->group_cnt
= group_cnt
;
5768 conf
->worker_cnt_per_group
= worker_cnt_per_group
;
5769 conf
->worker_groups
= new_group
;
5772 spin_lock_init(&conf
->device_lock
);
5773 seqcount_init(&conf
->gen_lock
);
5774 init_waitqueue_head(&conf
->wait_for_stripe
);
5775 init_waitqueue_head(&conf
->wait_for_overlap
);
5776 INIT_LIST_HEAD(&conf
->handle_list
);
5777 INIT_LIST_HEAD(&conf
->hold_list
);
5778 INIT_LIST_HEAD(&conf
->delayed_list
);
5779 INIT_LIST_HEAD(&conf
->bitmap_list
);
5780 init_llist_head(&conf
->released_stripes
);
5781 atomic_set(&conf
->active_stripes
, 0);
5782 atomic_set(&conf
->preread_active_stripes
, 0);
5783 atomic_set(&conf
->active_aligned_reads
, 0);
5784 conf
->bypass_threshold
= BYPASS_THRESHOLD
;
5785 conf
->recovery_disabled
= mddev
->recovery_disabled
- 1;
5787 conf
->raid_disks
= mddev
->raid_disks
;
5788 if (mddev
->reshape_position
== MaxSector
)
5789 conf
->previous_raid_disks
= mddev
->raid_disks
;
5791 conf
->previous_raid_disks
= mddev
->raid_disks
- mddev
->delta_disks
;
5792 max_disks
= max(conf
->raid_disks
, conf
->previous_raid_disks
);
5793 conf
->scribble_len
= scribble_len(max_disks
);
5795 conf
->disks
= kzalloc(max_disks
* sizeof(struct disk_info
),
5800 conf
->mddev
= mddev
;
5802 if ((conf
->stripe_hashtbl
= kzalloc(PAGE_SIZE
, GFP_KERNEL
)) == NULL
)
5805 /* We init hash_locks[0] separately to that it can be used
5806 * as the reference lock in the spin_lock_nest_lock() call
5807 * in lock_all_device_hash_locks_irq in order to convince
5808 * lockdep that we know what we are doing.
5810 spin_lock_init(conf
->hash_locks
);
5811 for (i
= 1; i
< NR_STRIPE_HASH_LOCKS
; i
++)
5812 spin_lock_init(conf
->hash_locks
+ i
);
5814 for (i
= 0; i
< NR_STRIPE_HASH_LOCKS
; i
++)
5815 INIT_LIST_HEAD(conf
->inactive_list
+ i
);
5817 for (i
= 0; i
< NR_STRIPE_HASH_LOCKS
; i
++)
5818 INIT_LIST_HEAD(conf
->temp_inactive_list
+ i
);
5820 conf
->level
= mddev
->new_level
;
5821 if (raid5_alloc_percpu(conf
) != 0)
5824 pr_debug("raid456: run(%s) called.\n", mdname(mddev
));
5826 rdev_for_each(rdev
, mddev
) {
5827 raid_disk
= rdev
->raid_disk
;
5828 if (raid_disk
>= max_disks
5831 disk
= conf
->disks
+ raid_disk
;
5833 if (test_bit(Replacement
, &rdev
->flags
)) {
5834 if (disk
->replacement
)
5836 disk
->replacement
= rdev
;
5843 if (test_bit(In_sync
, &rdev
->flags
)) {
5844 char b
[BDEVNAME_SIZE
];
5845 printk(KERN_INFO
"md/raid:%s: device %s operational as raid"
5847 mdname(mddev
), bdevname(rdev
->bdev
, b
), raid_disk
);
5848 } else if (rdev
->saved_raid_disk
!= raid_disk
)
5849 /* Cannot rely on bitmap to complete recovery */
5853 conf
->chunk_sectors
= mddev
->new_chunk_sectors
;
5854 conf
->level
= mddev
->new_level
;
5855 if (conf
->level
== 6)
5856 conf
->max_degraded
= 2;
5858 conf
->max_degraded
= 1;
5859 conf
->algorithm
= mddev
->new_layout
;
5860 conf
->reshape_progress
= mddev
->reshape_position
;
5861 if (conf
->reshape_progress
!= MaxSector
) {
5862 conf
->prev_chunk_sectors
= mddev
->chunk_sectors
;
5863 conf
->prev_algo
= mddev
->layout
;
5866 memory
= conf
->max_nr_stripes
* (sizeof(struct stripe_head
) +
5867 max_disks
* ((sizeof(struct bio
) + PAGE_SIZE
))) / 1024;
5868 atomic_set(&conf
->empty_inactive_list_nr
, NR_STRIPE_HASH_LOCKS
);
5869 if (grow_stripes(conf
, NR_STRIPES
)) {
5871 "md/raid:%s: couldn't allocate %dkB for buffers\n",
5872 mdname(mddev
), memory
);
5875 printk(KERN_INFO
"md/raid:%s: allocated %dkB\n",
5876 mdname(mddev
), memory
);
5878 sprintf(pers_name
, "raid%d", mddev
->new_level
);
5879 conf
->thread
= md_register_thread(raid5d
, mddev
, pers_name
);
5880 if (!conf
->thread
) {
5882 "md/raid:%s: couldn't allocate thread.\n",
5892 return ERR_PTR(-EIO
);
5894 return ERR_PTR(-ENOMEM
);
5898 static int only_parity(int raid_disk
, int algo
, int raid_disks
, int max_degraded
)
5901 case ALGORITHM_PARITY_0
:
5902 if (raid_disk
< max_degraded
)
5905 case ALGORITHM_PARITY_N
:
5906 if (raid_disk
>= raid_disks
- max_degraded
)
5909 case ALGORITHM_PARITY_0_6
:
5910 if (raid_disk
== 0 ||
5911 raid_disk
== raid_disks
- 1)
5914 case ALGORITHM_LEFT_ASYMMETRIC_6
:
5915 case ALGORITHM_RIGHT_ASYMMETRIC_6
:
5916 case ALGORITHM_LEFT_SYMMETRIC_6
:
5917 case ALGORITHM_RIGHT_SYMMETRIC_6
:
5918 if (raid_disk
== raid_disks
- 1)
5924 static int run(struct mddev
*mddev
)
5926 struct r5conf
*conf
;
5927 int working_disks
= 0;
5928 int dirty_parity_disks
= 0;
5929 struct md_rdev
*rdev
;
5930 sector_t reshape_offset
= 0;
5932 long long min_offset_diff
= 0;
5935 if (mddev
->recovery_cp
!= MaxSector
)
5936 printk(KERN_NOTICE
"md/raid:%s: not clean"
5937 " -- starting background reconstruction\n",
5940 rdev_for_each(rdev
, mddev
) {
5942 if (rdev
->raid_disk
< 0)
5944 diff
= (rdev
->new_data_offset
- rdev
->data_offset
);
5946 min_offset_diff
= diff
;
5948 } else if (mddev
->reshape_backwards
&&
5949 diff
< min_offset_diff
)
5950 min_offset_diff
= diff
;
5951 else if (!mddev
->reshape_backwards
&&
5952 diff
> min_offset_diff
)
5953 min_offset_diff
= diff
;
5956 if (mddev
->reshape_position
!= MaxSector
) {
5957 /* Check that we can continue the reshape.
5958 * Difficulties arise if the stripe we would write to
5959 * next is at or after the stripe we would read from next.
5960 * For a reshape that changes the number of devices, this
5961 * is only possible for a very short time, and mdadm makes
5962 * sure that time appears to have past before assembling
5963 * the array. So we fail if that time hasn't passed.
5964 * For a reshape that keeps the number of devices the same
5965 * mdadm must be monitoring the reshape can keeping the
5966 * critical areas read-only and backed up. It will start
5967 * the array in read-only mode, so we check for that.
5969 sector_t here_new
, here_old
;
5971 int max_degraded
= (mddev
->level
== 6 ? 2 : 1);
5973 if (mddev
->new_level
!= mddev
->level
) {
5974 printk(KERN_ERR
"md/raid:%s: unsupported reshape "
5975 "required - aborting.\n",
5979 old_disks
= mddev
->raid_disks
- mddev
->delta_disks
;
5980 /* reshape_position must be on a new-stripe boundary, and one
5981 * further up in new geometry must map after here in old
5984 here_new
= mddev
->reshape_position
;
5985 if (sector_div(here_new
, mddev
->new_chunk_sectors
*
5986 (mddev
->raid_disks
- max_degraded
))) {
5987 printk(KERN_ERR
"md/raid:%s: reshape_position not "
5988 "on a stripe boundary\n", mdname(mddev
));
5991 reshape_offset
= here_new
* mddev
->new_chunk_sectors
;
5992 /* here_new is the stripe we will write to */
5993 here_old
= mddev
->reshape_position
;
5994 sector_div(here_old
, mddev
->chunk_sectors
*
5995 (old_disks
-max_degraded
));
5996 /* here_old is the first stripe that we might need to read
5998 if (mddev
->delta_disks
== 0) {
5999 if ((here_new
* mddev
->new_chunk_sectors
!=
6000 here_old
* mddev
->chunk_sectors
)) {
6001 printk(KERN_ERR
"md/raid:%s: reshape position is"
6002 " confused - aborting\n", mdname(mddev
));
6005 /* We cannot be sure it is safe to start an in-place
6006 * reshape. It is only safe if user-space is monitoring
6007 * and taking constant backups.
6008 * mdadm always starts a situation like this in
6009 * readonly mode so it can take control before
6010 * allowing any writes. So just check for that.
6012 if (abs(min_offset_diff
) >= mddev
->chunk_sectors
&&
6013 abs(min_offset_diff
) >= mddev
->new_chunk_sectors
)
6014 /* not really in-place - so OK */;
6015 else if (mddev
->ro
== 0) {
6016 printk(KERN_ERR
"md/raid:%s: in-place reshape "
6017 "must be started in read-only mode "
6022 } else if (mddev
->reshape_backwards
6023 ? (here_new
* mddev
->new_chunk_sectors
+ min_offset_diff
<=
6024 here_old
* mddev
->chunk_sectors
)
6025 : (here_new
* mddev
->new_chunk_sectors
>=
6026 here_old
* mddev
->chunk_sectors
+ (-min_offset_diff
))) {
6027 /* Reading from the same stripe as writing to - bad */
6028 printk(KERN_ERR
"md/raid:%s: reshape_position too early for "
6029 "auto-recovery - aborting.\n",
6033 printk(KERN_INFO
"md/raid:%s: reshape will continue\n",
6035 /* OK, we should be able to continue; */
6037 BUG_ON(mddev
->level
!= mddev
->new_level
);
6038 BUG_ON(mddev
->layout
!= mddev
->new_layout
);
6039 BUG_ON(mddev
->chunk_sectors
!= mddev
->new_chunk_sectors
);
6040 BUG_ON(mddev
->delta_disks
!= 0);
6043 if (mddev
->private == NULL
)
6044 conf
= setup_conf(mddev
);
6046 conf
= mddev
->private;
6049 return PTR_ERR(conf
);
6051 conf
->min_offset_diff
= min_offset_diff
;
6052 mddev
->thread
= conf
->thread
;
6053 conf
->thread
= NULL
;
6054 mddev
->private = conf
;
6056 for (i
= 0; i
< conf
->raid_disks
&& conf
->previous_raid_disks
;
6058 rdev
= conf
->disks
[i
].rdev
;
6059 if (!rdev
&& conf
->disks
[i
].replacement
) {
6060 /* The replacement is all we have yet */
6061 rdev
= conf
->disks
[i
].replacement
;
6062 conf
->disks
[i
].replacement
= NULL
;
6063 clear_bit(Replacement
, &rdev
->flags
);
6064 conf
->disks
[i
].rdev
= rdev
;
6068 if (conf
->disks
[i
].replacement
&&
6069 conf
->reshape_progress
!= MaxSector
) {
6070 /* replacements and reshape simply do not mix. */
6071 printk(KERN_ERR
"md: cannot handle concurrent "
6072 "replacement and reshape.\n");
6075 if (test_bit(In_sync
, &rdev
->flags
)) {
6079 /* This disc is not fully in-sync. However if it
6080 * just stored parity (beyond the recovery_offset),
6081 * when we don't need to be concerned about the
6082 * array being dirty.
6083 * When reshape goes 'backwards', we never have
6084 * partially completed devices, so we only need
6085 * to worry about reshape going forwards.
6087 /* Hack because v0.91 doesn't store recovery_offset properly. */
6088 if (mddev
->major_version
== 0 &&
6089 mddev
->minor_version
> 90)
6090 rdev
->recovery_offset
= reshape_offset
;
6092 if (rdev
->recovery_offset
< reshape_offset
) {
6093 /* We need to check old and new layout */
6094 if (!only_parity(rdev
->raid_disk
,
6097 conf
->max_degraded
))
6100 if (!only_parity(rdev
->raid_disk
,
6102 conf
->previous_raid_disks
,
6103 conf
->max_degraded
))
6105 dirty_parity_disks
++;
6109 * 0 for a fully functional array, 1 or 2 for a degraded array.
6111 mddev
->degraded
= calc_degraded(conf
);
6113 if (has_failed(conf
)) {
6114 printk(KERN_ERR
"md/raid:%s: not enough operational devices"
6115 " (%d/%d failed)\n",
6116 mdname(mddev
), mddev
->degraded
, conf
->raid_disks
);
6120 /* device size must be a multiple of chunk size */
6121 mddev
->dev_sectors
&= ~(mddev
->chunk_sectors
- 1);
6122 mddev
->resync_max_sectors
= mddev
->dev_sectors
;
6124 if (mddev
->degraded
> dirty_parity_disks
&&
6125 mddev
->recovery_cp
!= MaxSector
) {
6126 if (mddev
->ok_start_degraded
)
6128 "md/raid:%s: starting dirty degraded array"
6129 " - data corruption possible.\n",
6133 "md/raid:%s: cannot start dirty degraded array.\n",
6139 if (mddev
->degraded
== 0)
6140 printk(KERN_INFO
"md/raid:%s: raid level %d active with %d out of %d"
6141 " devices, algorithm %d\n", mdname(mddev
), conf
->level
,
6142 mddev
->raid_disks
-mddev
->degraded
, mddev
->raid_disks
,
6145 printk(KERN_ALERT
"md/raid:%s: raid level %d active with %d"
6146 " out of %d devices, algorithm %d\n",
6147 mdname(mddev
), conf
->level
,
6148 mddev
->raid_disks
- mddev
->degraded
,
6149 mddev
->raid_disks
, mddev
->new_layout
);
6151 print_raid5_conf(conf
);
6153 if (conf
->reshape_progress
!= MaxSector
) {
6154 conf
->reshape_safe
= conf
->reshape_progress
;
6155 atomic_set(&conf
->reshape_stripes
, 0);
6156 clear_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
);
6157 clear_bit(MD_RECOVERY_CHECK
, &mddev
->recovery
);
6158 set_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
);
6159 set_bit(MD_RECOVERY_RUNNING
, &mddev
->recovery
);
6160 mddev
->sync_thread
= md_register_thread(md_do_sync
, mddev
,
6165 /* Ok, everything is just fine now */
6166 if (mddev
->to_remove
== &raid5_attrs_group
)
6167 mddev
->to_remove
= NULL
;
6168 else if (mddev
->kobj
.sd
&&
6169 sysfs_create_group(&mddev
->kobj
, &raid5_attrs_group
))
6171 "raid5: failed to create sysfs attributes for %s\n",
6173 md_set_array_sectors(mddev
, raid5_size(mddev
, 0, 0));
6177 bool discard_supported
= true;
6178 /* read-ahead size must cover two whole stripes, which
6179 * is 2 * (datadisks) * chunksize where 'n' is the
6180 * number of raid devices
6182 int data_disks
= conf
->previous_raid_disks
- conf
->max_degraded
;
6183 int stripe
= data_disks
*
6184 ((mddev
->chunk_sectors
<< 9) / PAGE_SIZE
);
6185 if (mddev
->queue
->backing_dev_info
.ra_pages
< 2 * stripe
)
6186 mddev
->queue
->backing_dev_info
.ra_pages
= 2 * stripe
;
6188 blk_queue_merge_bvec(mddev
->queue
, raid5_mergeable_bvec
);
6190 mddev
->queue
->backing_dev_info
.congested_data
= mddev
;
6191 mddev
->queue
->backing_dev_info
.congested_fn
= raid5_congested
;
6193 chunk_size
= mddev
->chunk_sectors
<< 9;
6194 blk_queue_io_min(mddev
->queue
, chunk_size
);
6195 blk_queue_io_opt(mddev
->queue
, chunk_size
*
6196 (conf
->raid_disks
- conf
->max_degraded
));
6197 mddev
->queue
->limits
.raid_partial_stripes_expensive
= 1;
6199 * We can only discard a whole stripe. It doesn't make sense to
6200 * discard data disk but write parity disk
6202 stripe
= stripe
* PAGE_SIZE
;
6203 /* Round up to power of 2, as discard handling
6204 * currently assumes that */
6205 while ((stripe
-1) & stripe
)
6206 stripe
= (stripe
| (stripe
-1)) + 1;
6207 mddev
->queue
->limits
.discard_alignment
= stripe
;
6208 mddev
->queue
->limits
.discard_granularity
= stripe
;
6210 * unaligned part of discard request will be ignored, so can't
6211 * guarantee discard_zerors_data
6213 mddev
->queue
->limits
.discard_zeroes_data
= 0;
6215 blk_queue_max_write_same_sectors(mddev
->queue
, 0);
6217 rdev_for_each(rdev
, mddev
) {
6218 disk_stack_limits(mddev
->gendisk
, rdev
->bdev
,
6219 rdev
->data_offset
<< 9);
6220 disk_stack_limits(mddev
->gendisk
, rdev
->bdev
,
6221 rdev
->new_data_offset
<< 9);
6223 * discard_zeroes_data is required, otherwise data
6224 * could be lost. Consider a scenario: discard a stripe
6225 * (the stripe could be inconsistent if
6226 * discard_zeroes_data is 0); write one disk of the
6227 * stripe (the stripe could be inconsistent again
6228 * depending on which disks are used to calculate
6229 * parity); the disk is broken; The stripe data of this
6232 if (!blk_queue_discard(bdev_get_queue(rdev
->bdev
)) ||
6233 !bdev_get_queue(rdev
->bdev
)->
6234 limits
.discard_zeroes_data
)
6235 discard_supported
= false;
6238 if (discard_supported
&&
6239 mddev
->queue
->limits
.max_discard_sectors
>= stripe
&&
6240 mddev
->queue
->limits
.discard_granularity
>= stripe
)
6241 queue_flag_set_unlocked(QUEUE_FLAG_DISCARD
,
6244 queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD
,
6250 md_unregister_thread(&mddev
->thread
);
6251 print_raid5_conf(conf
);
6253 mddev
->private = NULL
;
6254 printk(KERN_ALERT
"md/raid:%s: failed to run raid set.\n", mdname(mddev
));
6258 static int stop(struct mddev
*mddev
)
6260 struct r5conf
*conf
= mddev
->private;
6262 md_unregister_thread(&mddev
->thread
);
6264 mddev
->queue
->backing_dev_info
.congested_fn
= NULL
;
6266 mddev
->private = NULL
;
6267 mddev
->to_remove
= &raid5_attrs_group
;
6271 static void status(struct seq_file
*seq
, struct mddev
*mddev
)
6273 struct r5conf
*conf
= mddev
->private;
6276 seq_printf(seq
, " level %d, %dk chunk, algorithm %d", mddev
->level
,
6277 mddev
->chunk_sectors
/ 2, mddev
->layout
);
6278 seq_printf (seq
, " [%d/%d] [", conf
->raid_disks
, conf
->raid_disks
- mddev
->degraded
);
6279 for (i
= 0; i
< conf
->raid_disks
; i
++)
6280 seq_printf (seq
, "%s",
6281 conf
->disks
[i
].rdev
&&
6282 test_bit(In_sync
, &conf
->disks
[i
].rdev
->flags
) ? "U" : "_");
6283 seq_printf (seq
, "]");
6286 static void print_raid5_conf (struct r5conf
*conf
)
6289 struct disk_info
*tmp
;
6291 printk(KERN_DEBUG
"RAID conf printout:\n");
6293 printk("(conf==NULL)\n");
6296 printk(KERN_DEBUG
" --- level:%d rd:%d wd:%d\n", conf
->level
,
6298 conf
->raid_disks
- conf
->mddev
->degraded
);
6300 for (i
= 0; i
< conf
->raid_disks
; i
++) {
6301 char b
[BDEVNAME_SIZE
];
6302 tmp
= conf
->disks
+ i
;
6304 printk(KERN_DEBUG
" disk %d, o:%d, dev:%s\n",
6305 i
, !test_bit(Faulty
, &tmp
->rdev
->flags
),
6306 bdevname(tmp
->rdev
->bdev
, b
));
6310 static int raid5_spare_active(struct mddev
*mddev
)
6313 struct r5conf
*conf
= mddev
->private;
6314 struct disk_info
*tmp
;
6316 unsigned long flags
;
6318 for (i
= 0; i
< conf
->raid_disks
; i
++) {
6319 tmp
= conf
->disks
+ i
;
6320 if (tmp
->replacement
6321 && tmp
->replacement
->recovery_offset
== MaxSector
6322 && !test_bit(Faulty
, &tmp
->replacement
->flags
)
6323 && !test_and_set_bit(In_sync
, &tmp
->replacement
->flags
)) {
6324 /* Replacement has just become active. */
6326 || !test_and_clear_bit(In_sync
, &tmp
->rdev
->flags
))
6329 /* Replaced device not technically faulty,
6330 * but we need to be sure it gets removed
6331 * and never re-added.
6333 set_bit(Faulty
, &tmp
->rdev
->flags
);
6334 sysfs_notify_dirent_safe(
6335 tmp
->rdev
->sysfs_state
);
6337 sysfs_notify_dirent_safe(tmp
->replacement
->sysfs_state
);
6338 } else if (tmp
->rdev
6339 && tmp
->rdev
->recovery_offset
== MaxSector
6340 && !test_bit(Faulty
, &tmp
->rdev
->flags
)
6341 && !test_and_set_bit(In_sync
, &tmp
->rdev
->flags
)) {
6343 sysfs_notify_dirent_safe(tmp
->rdev
->sysfs_state
);
6346 spin_lock_irqsave(&conf
->device_lock
, flags
);
6347 mddev
->degraded
= calc_degraded(conf
);
6348 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
6349 print_raid5_conf(conf
);
6353 static int raid5_remove_disk(struct mddev
*mddev
, struct md_rdev
*rdev
)
6355 struct r5conf
*conf
= mddev
->private;
6357 int number
= rdev
->raid_disk
;
6358 struct md_rdev
**rdevp
;
6359 struct disk_info
*p
= conf
->disks
+ number
;
6361 print_raid5_conf(conf
);
6362 if (rdev
== p
->rdev
)
6364 else if (rdev
== p
->replacement
)
6365 rdevp
= &p
->replacement
;
6369 if (number
>= conf
->raid_disks
&&
6370 conf
->reshape_progress
== MaxSector
)
6371 clear_bit(In_sync
, &rdev
->flags
);
6373 if (test_bit(In_sync
, &rdev
->flags
) ||
6374 atomic_read(&rdev
->nr_pending
)) {
6378 /* Only remove non-faulty devices if recovery
6381 if (!test_bit(Faulty
, &rdev
->flags
) &&
6382 mddev
->recovery_disabled
!= conf
->recovery_disabled
&&
6383 !has_failed(conf
) &&
6384 (!p
->replacement
|| p
->replacement
== rdev
) &&
6385 number
< conf
->raid_disks
) {
6391 if (atomic_read(&rdev
->nr_pending
)) {
6392 /* lost the race, try later */
6395 } else if (p
->replacement
) {
6396 /* We must have just cleared 'rdev' */
6397 p
->rdev
= p
->replacement
;
6398 clear_bit(Replacement
, &p
->replacement
->flags
);
6399 smp_mb(); /* Make sure other CPUs may see both as identical
6400 * but will never see neither - if they are careful
6402 p
->replacement
= NULL
;
6403 clear_bit(WantReplacement
, &rdev
->flags
);
6405 /* We might have just removed the Replacement as faulty-
6406 * clear the bit just in case
6408 clear_bit(WantReplacement
, &rdev
->flags
);
6411 print_raid5_conf(conf
);
6415 static int raid5_add_disk(struct mddev
*mddev
, struct md_rdev
*rdev
)
6417 struct r5conf
*conf
= mddev
->private;
6420 struct disk_info
*p
;
6422 int last
= conf
->raid_disks
- 1;
6424 if (mddev
->recovery_disabled
== conf
->recovery_disabled
)
6427 if (rdev
->saved_raid_disk
< 0 && has_failed(conf
))
6428 /* no point adding a device */
6431 if (rdev
->raid_disk
>= 0)
6432 first
= last
= rdev
->raid_disk
;
6435 * find the disk ... but prefer rdev->saved_raid_disk
6438 if (rdev
->saved_raid_disk
>= 0 &&
6439 rdev
->saved_raid_disk
>= first
&&
6440 conf
->disks
[rdev
->saved_raid_disk
].rdev
== NULL
)
6441 first
= rdev
->saved_raid_disk
;
6443 for (disk
= first
; disk
<= last
; disk
++) {
6444 p
= conf
->disks
+ disk
;
6445 if (p
->rdev
== NULL
) {
6446 clear_bit(In_sync
, &rdev
->flags
);
6447 rdev
->raid_disk
= disk
;
6449 if (rdev
->saved_raid_disk
!= disk
)
6451 rcu_assign_pointer(p
->rdev
, rdev
);
6455 for (disk
= first
; disk
<= last
; disk
++) {
6456 p
= conf
->disks
+ disk
;
6457 if (test_bit(WantReplacement
, &p
->rdev
->flags
) &&
6458 p
->replacement
== NULL
) {
6459 clear_bit(In_sync
, &rdev
->flags
);
6460 set_bit(Replacement
, &rdev
->flags
);
6461 rdev
->raid_disk
= disk
;
6464 rcu_assign_pointer(p
->replacement
, rdev
);
6469 print_raid5_conf(conf
);
6473 static int raid5_resize(struct mddev
*mddev
, sector_t sectors
)
6475 /* no resync is happening, and there is enough space
6476 * on all devices, so we can resize.
6477 * We need to make sure resync covers any new space.
6478 * If the array is shrinking we should possibly wait until
6479 * any io in the removed space completes, but it hardly seems
6483 sectors
&= ~((sector_t
)mddev
->chunk_sectors
- 1);
6484 newsize
= raid5_size(mddev
, sectors
, mddev
->raid_disks
);
6485 if (mddev
->external_size
&&
6486 mddev
->array_sectors
> newsize
)
6488 if (mddev
->bitmap
) {
6489 int ret
= bitmap_resize(mddev
->bitmap
, sectors
, 0, 0);
6493 md_set_array_sectors(mddev
, newsize
);
6494 set_capacity(mddev
->gendisk
, mddev
->array_sectors
);
6495 revalidate_disk(mddev
->gendisk
);
6496 if (sectors
> mddev
->dev_sectors
&&
6497 mddev
->recovery_cp
> mddev
->dev_sectors
) {
6498 mddev
->recovery_cp
= mddev
->dev_sectors
;
6499 set_bit(MD_RECOVERY_NEEDED
, &mddev
->recovery
);
6501 mddev
->dev_sectors
= sectors
;
6502 mddev
->resync_max_sectors
= sectors
;
6506 static int check_stripe_cache(struct mddev
*mddev
)
6508 /* Can only proceed if there are plenty of stripe_heads.
6509 * We need a minimum of one full stripe,, and for sensible progress
6510 * it is best to have about 4 times that.
6511 * If we require 4 times, then the default 256 4K stripe_heads will
6512 * allow for chunk sizes up to 256K, which is probably OK.
6513 * If the chunk size is greater, user-space should request more
6514 * stripe_heads first.
6516 struct r5conf
*conf
= mddev
->private;
6517 if (((mddev
->chunk_sectors
<< 9) / STRIPE_SIZE
) * 4
6518 > conf
->max_nr_stripes
||
6519 ((mddev
->new_chunk_sectors
<< 9) / STRIPE_SIZE
) * 4
6520 > conf
->max_nr_stripes
) {
6521 printk(KERN_WARNING
"md/raid:%s: reshape: not enough stripes. Needed %lu\n",
6523 ((max(mddev
->chunk_sectors
, mddev
->new_chunk_sectors
) << 9)
6530 static int check_reshape(struct mddev
*mddev
)
6532 struct r5conf
*conf
= mddev
->private;
6534 if (mddev
->delta_disks
== 0 &&
6535 mddev
->new_layout
== mddev
->layout
&&
6536 mddev
->new_chunk_sectors
== mddev
->chunk_sectors
)
6537 return 0; /* nothing to do */
6538 if (has_failed(conf
))
6540 if (mddev
->delta_disks
< 0 && mddev
->reshape_position
== MaxSector
) {
6541 /* We might be able to shrink, but the devices must
6542 * be made bigger first.
6543 * For raid6, 4 is the minimum size.
6544 * Otherwise 2 is the minimum
6547 if (mddev
->level
== 6)
6549 if (mddev
->raid_disks
+ mddev
->delta_disks
< min
)
6553 if (!check_stripe_cache(mddev
))
6556 return resize_stripes(conf
, (conf
->previous_raid_disks
6557 + mddev
->delta_disks
));
6560 static int raid5_start_reshape(struct mddev
*mddev
)
6562 struct r5conf
*conf
= mddev
->private;
6563 struct md_rdev
*rdev
;
6565 unsigned long flags
;
6567 if (test_bit(MD_RECOVERY_RUNNING
, &mddev
->recovery
))
6570 if (!check_stripe_cache(mddev
))
6573 if (has_failed(conf
))
6576 rdev_for_each(rdev
, mddev
) {
6577 if (!test_bit(In_sync
, &rdev
->flags
)
6578 && !test_bit(Faulty
, &rdev
->flags
))
6582 if (spares
- mddev
->degraded
< mddev
->delta_disks
- conf
->max_degraded
)
6583 /* Not enough devices even to make a degraded array
6588 /* Refuse to reduce size of the array. Any reductions in
6589 * array size must be through explicit setting of array_size
6592 if (raid5_size(mddev
, 0, conf
->raid_disks
+ mddev
->delta_disks
)
6593 < mddev
->array_sectors
) {
6594 printk(KERN_ERR
"md/raid:%s: array size must be reduced "
6595 "before number of disks\n", mdname(mddev
));
6599 atomic_set(&conf
->reshape_stripes
, 0);
6600 spin_lock_irq(&conf
->device_lock
);
6601 write_seqcount_begin(&conf
->gen_lock
);
6602 conf
->previous_raid_disks
= conf
->raid_disks
;
6603 conf
->raid_disks
+= mddev
->delta_disks
;
6604 conf
->prev_chunk_sectors
= conf
->chunk_sectors
;
6605 conf
->chunk_sectors
= mddev
->new_chunk_sectors
;
6606 conf
->prev_algo
= conf
->algorithm
;
6607 conf
->algorithm
= mddev
->new_layout
;
6609 /* Code that selects data_offset needs to see the generation update
6610 * if reshape_progress has been set - so a memory barrier needed.
6613 if (mddev
->reshape_backwards
)
6614 conf
->reshape_progress
= raid5_size(mddev
, 0, 0);
6616 conf
->reshape_progress
= 0;
6617 conf
->reshape_safe
= conf
->reshape_progress
;
6618 write_seqcount_end(&conf
->gen_lock
);
6619 spin_unlock_irq(&conf
->device_lock
);
6621 /* Now make sure any requests that proceeded on the assumption
6622 * the reshape wasn't running - like Discard or Read - have
6625 mddev_suspend(mddev
);
6626 mddev_resume(mddev
);
6628 /* Add some new drives, as many as will fit.
6629 * We know there are enough to make the newly sized array work.
6630 * Don't add devices if we are reducing the number of
6631 * devices in the array. This is because it is not possible
6632 * to correctly record the "partially reconstructed" state of
6633 * such devices during the reshape and confusion could result.
6635 if (mddev
->delta_disks
>= 0) {
6636 rdev_for_each(rdev
, mddev
)
6637 if (rdev
->raid_disk
< 0 &&
6638 !test_bit(Faulty
, &rdev
->flags
)) {
6639 if (raid5_add_disk(mddev
, rdev
) == 0) {
6641 >= conf
->previous_raid_disks
)
6642 set_bit(In_sync
, &rdev
->flags
);
6644 rdev
->recovery_offset
= 0;
6646 if (sysfs_link_rdev(mddev
, rdev
))
6647 /* Failure here is OK */;
6649 } else if (rdev
->raid_disk
>= conf
->previous_raid_disks
6650 && !test_bit(Faulty
, &rdev
->flags
)) {
6651 /* This is a spare that was manually added */
6652 set_bit(In_sync
, &rdev
->flags
);
6655 /* When a reshape changes the number of devices,
6656 * ->degraded is measured against the larger of the
6657 * pre and post number of devices.
6659 spin_lock_irqsave(&conf
->device_lock
, flags
);
6660 mddev
->degraded
= calc_degraded(conf
);
6661 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
6663 mddev
->raid_disks
= conf
->raid_disks
;
6664 mddev
->reshape_position
= conf
->reshape_progress
;
6665 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
6667 clear_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
);
6668 clear_bit(MD_RECOVERY_CHECK
, &mddev
->recovery
);
6669 set_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
);
6670 set_bit(MD_RECOVERY_RUNNING
, &mddev
->recovery
);
6671 mddev
->sync_thread
= md_register_thread(md_do_sync
, mddev
,
6673 if (!mddev
->sync_thread
) {
6674 mddev
->recovery
= 0;
6675 spin_lock_irq(&conf
->device_lock
);
6676 write_seqcount_begin(&conf
->gen_lock
);
6677 mddev
->raid_disks
= conf
->raid_disks
= conf
->previous_raid_disks
;
6678 mddev
->new_chunk_sectors
=
6679 conf
->chunk_sectors
= conf
->prev_chunk_sectors
;
6680 mddev
->new_layout
= conf
->algorithm
= conf
->prev_algo
;
6681 rdev_for_each(rdev
, mddev
)
6682 rdev
->new_data_offset
= rdev
->data_offset
;
6684 conf
->generation
--;
6685 conf
->reshape_progress
= MaxSector
;
6686 mddev
->reshape_position
= MaxSector
;
6687 write_seqcount_end(&conf
->gen_lock
);
6688 spin_unlock_irq(&conf
->device_lock
);
6691 conf
->reshape_checkpoint
= jiffies
;
6692 md_wakeup_thread(mddev
->sync_thread
);
6693 md_new_event(mddev
);
6697 /* This is called from the reshape thread and should make any
6698 * changes needed in 'conf'
6700 static void end_reshape(struct r5conf
*conf
)
6703 if (!test_bit(MD_RECOVERY_INTR
, &conf
->mddev
->recovery
)) {
6704 struct md_rdev
*rdev
;
6706 spin_lock_irq(&conf
->device_lock
);
6707 conf
->previous_raid_disks
= conf
->raid_disks
;
6708 rdev_for_each(rdev
, conf
->mddev
)
6709 rdev
->data_offset
= rdev
->new_data_offset
;
6711 conf
->reshape_progress
= MaxSector
;
6712 spin_unlock_irq(&conf
->device_lock
);
6713 wake_up(&conf
->wait_for_overlap
);
6715 /* read-ahead size must cover two whole stripes, which is
6716 * 2 * (datadisks) * chunksize where 'n' is the number of raid devices
6718 if (conf
->mddev
->queue
) {
6719 int data_disks
= conf
->raid_disks
- conf
->max_degraded
;
6720 int stripe
= data_disks
* ((conf
->chunk_sectors
<< 9)
6722 if (conf
->mddev
->queue
->backing_dev_info
.ra_pages
< 2 * stripe
)
6723 conf
->mddev
->queue
->backing_dev_info
.ra_pages
= 2 * stripe
;
6728 /* This is called from the raid5d thread with mddev_lock held.
6729 * It makes config changes to the device.
6731 static void raid5_finish_reshape(struct mddev
*mddev
)
6733 struct r5conf
*conf
= mddev
->private;
6735 if (!test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
)) {
6737 if (mddev
->delta_disks
> 0) {
6738 md_set_array_sectors(mddev
, raid5_size(mddev
, 0, 0));
6739 set_capacity(mddev
->gendisk
, mddev
->array_sectors
);
6740 revalidate_disk(mddev
->gendisk
);
6743 spin_lock_irq(&conf
->device_lock
);
6744 mddev
->degraded
= calc_degraded(conf
);
6745 spin_unlock_irq(&conf
->device_lock
);
6746 for (d
= conf
->raid_disks
;
6747 d
< conf
->raid_disks
- mddev
->delta_disks
;
6749 struct md_rdev
*rdev
= conf
->disks
[d
].rdev
;
6751 clear_bit(In_sync
, &rdev
->flags
);
6752 rdev
= conf
->disks
[d
].replacement
;
6754 clear_bit(In_sync
, &rdev
->flags
);
6757 mddev
->layout
= conf
->algorithm
;
6758 mddev
->chunk_sectors
= conf
->chunk_sectors
;
6759 mddev
->reshape_position
= MaxSector
;
6760 mddev
->delta_disks
= 0;
6761 mddev
->reshape_backwards
= 0;
6765 static void raid5_quiesce(struct mddev
*mddev
, int state
)
6767 struct r5conf
*conf
= mddev
->private;
6770 case 2: /* resume for a suspend */
6771 wake_up(&conf
->wait_for_overlap
);
6774 case 1: /* stop all writes */
6775 lock_all_device_hash_locks_irq(conf
);
6776 /* '2' tells resync/reshape to pause so that all
6777 * active stripes can drain
6780 wait_event_cmd(conf
->wait_for_stripe
,
6781 atomic_read(&conf
->active_stripes
) == 0 &&
6782 atomic_read(&conf
->active_aligned_reads
) == 0,
6783 unlock_all_device_hash_locks_irq(conf
),
6784 lock_all_device_hash_locks_irq(conf
));
6786 unlock_all_device_hash_locks_irq(conf
);
6787 /* allow reshape to continue */
6788 wake_up(&conf
->wait_for_overlap
);
6791 case 0: /* re-enable writes */
6792 lock_all_device_hash_locks_irq(conf
);
6794 wake_up(&conf
->wait_for_stripe
);
6795 wake_up(&conf
->wait_for_overlap
);
6796 unlock_all_device_hash_locks_irq(conf
);
6802 static void *raid45_takeover_raid0(struct mddev
*mddev
, int level
)
6804 struct r0conf
*raid0_conf
= mddev
->private;
6807 /* for raid0 takeover only one zone is supported */
6808 if (raid0_conf
->nr_strip_zones
> 1) {
6809 printk(KERN_ERR
"md/raid:%s: cannot takeover raid0 with more than one zone.\n",
6811 return ERR_PTR(-EINVAL
);
6814 sectors
= raid0_conf
->strip_zone
[0].zone_end
;
6815 sector_div(sectors
, raid0_conf
->strip_zone
[0].nb_dev
);
6816 mddev
->dev_sectors
= sectors
;
6817 mddev
->new_level
= level
;
6818 mddev
->new_layout
= ALGORITHM_PARITY_N
;
6819 mddev
->new_chunk_sectors
= mddev
->chunk_sectors
;
6820 mddev
->raid_disks
+= 1;
6821 mddev
->delta_disks
= 1;
6822 /* make sure it will be not marked as dirty */
6823 mddev
->recovery_cp
= MaxSector
;
6825 return setup_conf(mddev
);
6829 static void *raid5_takeover_raid1(struct mddev
*mddev
)
6833 if (mddev
->raid_disks
!= 2 ||
6834 mddev
->degraded
> 1)
6835 return ERR_PTR(-EINVAL
);
6837 /* Should check if there are write-behind devices? */
6839 chunksect
= 64*2; /* 64K by default */
6841 /* The array must be an exact multiple of chunksize */
6842 while (chunksect
&& (mddev
->array_sectors
& (chunksect
-1)))
6845 if ((chunksect
<<9) < STRIPE_SIZE
)
6846 /* array size does not allow a suitable chunk size */
6847 return ERR_PTR(-EINVAL
);
6849 mddev
->new_level
= 5;
6850 mddev
->new_layout
= ALGORITHM_LEFT_SYMMETRIC
;
6851 mddev
->new_chunk_sectors
= chunksect
;
6853 return setup_conf(mddev
);
6856 static void *raid5_takeover_raid6(struct mddev
*mddev
)
6860 switch (mddev
->layout
) {
6861 case ALGORITHM_LEFT_ASYMMETRIC_6
:
6862 new_layout
= ALGORITHM_LEFT_ASYMMETRIC
;
6864 case ALGORITHM_RIGHT_ASYMMETRIC_6
:
6865 new_layout
= ALGORITHM_RIGHT_ASYMMETRIC
;
6867 case ALGORITHM_LEFT_SYMMETRIC_6
:
6868 new_layout
= ALGORITHM_LEFT_SYMMETRIC
;
6870 case ALGORITHM_RIGHT_SYMMETRIC_6
:
6871 new_layout
= ALGORITHM_RIGHT_SYMMETRIC
;
6873 case ALGORITHM_PARITY_0_6
:
6874 new_layout
= ALGORITHM_PARITY_0
;
6876 case ALGORITHM_PARITY_N
:
6877 new_layout
= ALGORITHM_PARITY_N
;
6880 return ERR_PTR(-EINVAL
);
6882 mddev
->new_level
= 5;
6883 mddev
->new_layout
= new_layout
;
6884 mddev
->delta_disks
= -1;
6885 mddev
->raid_disks
-= 1;
6886 return setup_conf(mddev
);
6890 static int raid5_check_reshape(struct mddev
*mddev
)
6892 /* For a 2-drive array, the layout and chunk size can be changed
6893 * immediately as not restriping is needed.
6894 * For larger arrays we record the new value - after validation
6895 * to be used by a reshape pass.
6897 struct r5conf
*conf
= mddev
->private;
6898 int new_chunk
= mddev
->new_chunk_sectors
;
6900 if (mddev
->new_layout
>= 0 && !algorithm_valid_raid5(mddev
->new_layout
))
6902 if (new_chunk
> 0) {
6903 if (!is_power_of_2(new_chunk
))
6905 if (new_chunk
< (PAGE_SIZE
>>9))
6907 if (mddev
->array_sectors
& (new_chunk
-1))
6908 /* not factor of array size */
6912 /* They look valid */
6914 if (mddev
->raid_disks
== 2) {
6915 /* can make the change immediately */
6916 if (mddev
->new_layout
>= 0) {
6917 conf
->algorithm
= mddev
->new_layout
;
6918 mddev
->layout
= mddev
->new_layout
;
6920 if (new_chunk
> 0) {
6921 conf
->chunk_sectors
= new_chunk
;
6922 mddev
->chunk_sectors
= new_chunk
;
6924 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
6925 md_wakeup_thread(mddev
->thread
);
6927 return check_reshape(mddev
);
6930 static int raid6_check_reshape(struct mddev
*mddev
)
6932 int new_chunk
= mddev
->new_chunk_sectors
;
6934 if (mddev
->new_layout
>= 0 && !algorithm_valid_raid6(mddev
->new_layout
))
6936 if (new_chunk
> 0) {
6937 if (!is_power_of_2(new_chunk
))
6939 if (new_chunk
< (PAGE_SIZE
>> 9))
6941 if (mddev
->array_sectors
& (new_chunk
-1))
6942 /* not factor of array size */
6946 /* They look valid */
6947 return check_reshape(mddev
);
6950 static void *raid5_takeover(struct mddev
*mddev
)
6952 /* raid5 can take over:
6953 * raid0 - if there is only one strip zone - make it a raid4 layout
6954 * raid1 - if there are two drives. We need to know the chunk size
6955 * raid4 - trivial - just use a raid4 layout.
6956 * raid6 - Providing it is a *_6 layout
6958 if (mddev
->level
== 0)
6959 return raid45_takeover_raid0(mddev
, 5);
6960 if (mddev
->level
== 1)
6961 return raid5_takeover_raid1(mddev
);
6962 if (mddev
->level
== 4) {
6963 mddev
->new_layout
= ALGORITHM_PARITY_N
;
6964 mddev
->new_level
= 5;
6965 return setup_conf(mddev
);
6967 if (mddev
->level
== 6)
6968 return raid5_takeover_raid6(mddev
);
6970 return ERR_PTR(-EINVAL
);
6973 static void *raid4_takeover(struct mddev
*mddev
)
6975 /* raid4 can take over:
6976 * raid0 - if there is only one strip zone
6977 * raid5 - if layout is right
6979 if (mddev
->level
== 0)
6980 return raid45_takeover_raid0(mddev
, 4);
6981 if (mddev
->level
== 5 &&
6982 mddev
->layout
== ALGORITHM_PARITY_N
) {
6983 mddev
->new_layout
= 0;
6984 mddev
->new_level
= 4;
6985 return setup_conf(mddev
);
6987 return ERR_PTR(-EINVAL
);
6990 static struct md_personality raid5_personality
;
6992 static void *raid6_takeover(struct mddev
*mddev
)
6994 /* Currently can only take over a raid5. We map the
6995 * personality to an equivalent raid6 personality
6996 * with the Q block at the end.
7000 if (mddev
->pers
!= &raid5_personality
)
7001 return ERR_PTR(-EINVAL
);
7002 if (mddev
->degraded
> 1)
7003 return ERR_PTR(-EINVAL
);
7004 if (mddev
->raid_disks
> 253)
7005 return ERR_PTR(-EINVAL
);
7006 if (mddev
->raid_disks
< 3)
7007 return ERR_PTR(-EINVAL
);
7009 switch (mddev
->layout
) {
7010 case ALGORITHM_LEFT_ASYMMETRIC
:
7011 new_layout
= ALGORITHM_LEFT_ASYMMETRIC_6
;
7013 case ALGORITHM_RIGHT_ASYMMETRIC
:
7014 new_layout
= ALGORITHM_RIGHT_ASYMMETRIC_6
;
7016 case ALGORITHM_LEFT_SYMMETRIC
:
7017 new_layout
= ALGORITHM_LEFT_SYMMETRIC_6
;
7019 case ALGORITHM_RIGHT_SYMMETRIC
:
7020 new_layout
= ALGORITHM_RIGHT_SYMMETRIC_6
;
7022 case ALGORITHM_PARITY_0
:
7023 new_layout
= ALGORITHM_PARITY_0_6
;
7025 case ALGORITHM_PARITY_N
:
7026 new_layout
= ALGORITHM_PARITY_N
;
7029 return ERR_PTR(-EINVAL
);
7031 mddev
->new_level
= 6;
7032 mddev
->new_layout
= new_layout
;
7033 mddev
->delta_disks
= 1;
7034 mddev
->raid_disks
+= 1;
7035 return setup_conf(mddev
);
7039 static struct md_personality raid6_personality
=
7043 .owner
= THIS_MODULE
,
7044 .make_request
= make_request
,
7048 .error_handler
= error
,
7049 .hot_add_disk
= raid5_add_disk
,
7050 .hot_remove_disk
= raid5_remove_disk
,
7051 .spare_active
= raid5_spare_active
,
7052 .sync_request
= sync_request
,
7053 .resize
= raid5_resize
,
7055 .check_reshape
= raid6_check_reshape
,
7056 .start_reshape
= raid5_start_reshape
,
7057 .finish_reshape
= raid5_finish_reshape
,
7058 .quiesce
= raid5_quiesce
,
7059 .takeover
= raid6_takeover
,
7061 static struct md_personality raid5_personality
=
7065 .owner
= THIS_MODULE
,
7066 .make_request
= make_request
,
7070 .error_handler
= error
,
7071 .hot_add_disk
= raid5_add_disk
,
7072 .hot_remove_disk
= raid5_remove_disk
,
7073 .spare_active
= raid5_spare_active
,
7074 .sync_request
= sync_request
,
7075 .resize
= raid5_resize
,
7077 .check_reshape
= raid5_check_reshape
,
7078 .start_reshape
= raid5_start_reshape
,
7079 .finish_reshape
= raid5_finish_reshape
,
7080 .quiesce
= raid5_quiesce
,
7081 .takeover
= raid5_takeover
,
7084 static struct md_personality raid4_personality
=
7088 .owner
= THIS_MODULE
,
7089 .make_request
= make_request
,
7093 .error_handler
= error
,
7094 .hot_add_disk
= raid5_add_disk
,
7095 .hot_remove_disk
= raid5_remove_disk
,
7096 .spare_active
= raid5_spare_active
,
7097 .sync_request
= sync_request
,
7098 .resize
= raid5_resize
,
7100 .check_reshape
= raid5_check_reshape
,
7101 .start_reshape
= raid5_start_reshape
,
7102 .finish_reshape
= raid5_finish_reshape
,
7103 .quiesce
= raid5_quiesce
,
7104 .takeover
= raid4_takeover
,
7107 static int __init
raid5_init(void)
7109 raid5_wq
= alloc_workqueue("raid5wq",
7110 WQ_UNBOUND
|WQ_MEM_RECLAIM
|WQ_CPU_INTENSIVE
|WQ_SYSFS
, 0);
7113 register_md_personality(&raid6_personality
);
7114 register_md_personality(&raid5_personality
);
7115 register_md_personality(&raid4_personality
);
7119 static void raid5_exit(void)
7121 unregister_md_personality(&raid6_personality
);
7122 unregister_md_personality(&raid5_personality
);
7123 unregister_md_personality(&raid4_personality
);
7124 destroy_workqueue(raid5_wq
);
7127 module_init(raid5_init
);
7128 module_exit(raid5_exit
);
7129 MODULE_LICENSE("GPL");
7130 MODULE_DESCRIPTION("RAID4/5/6 (striping with parity) personality for MD");
7131 MODULE_ALIAS("md-personality-4"); /* RAID5 */
7132 MODULE_ALIAS("md-raid5");
7133 MODULE_ALIAS("md-raid4");
7134 MODULE_ALIAS("md-level-5");
7135 MODULE_ALIAS("md-level-4");
7136 MODULE_ALIAS("md-personality-8"); /* RAID6 */
7137 MODULE_ALIAS("md-raid6");
7138 MODULE_ALIAS("md-level-6");
7140 /* This used to be two separate modules, they were: */
7141 MODULE_ALIAS("raid5");
7142 MODULE_ALIAS("raid6");