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 bool devices_handle_discard_safely
= false;
68 module_param(devices_handle_discard_safely
, bool, 0644);
69 MODULE_PARM_DESC(devices_handle_discard_safely
,
70 "Set to Y if all devices in each array reliably return zeroes on reads from discarded regions");
71 static struct workqueue_struct
*raid5_wq
;
76 #define NR_STRIPES 256
77 #define STRIPE_SIZE PAGE_SIZE
78 #define STRIPE_SHIFT (PAGE_SHIFT - 9)
79 #define STRIPE_SECTORS (STRIPE_SIZE>>9)
80 #define IO_THRESHOLD 1
81 #define BYPASS_THRESHOLD 1
82 #define NR_HASH (PAGE_SIZE / sizeof(struct hlist_head))
83 #define HASH_MASK (NR_HASH - 1)
84 #define MAX_STRIPE_BATCH 8
86 static inline struct hlist_head
*stripe_hash(struct r5conf
*conf
, sector_t sect
)
88 int hash
= (sect
>> STRIPE_SHIFT
) & HASH_MASK
;
89 return &conf
->stripe_hashtbl
[hash
];
92 static inline int stripe_hash_locks_hash(sector_t sect
)
94 return (sect
>> STRIPE_SHIFT
) & STRIPE_HASH_LOCKS_MASK
;
97 static inline void lock_device_hash_lock(struct r5conf
*conf
, int hash
)
99 spin_lock_irq(conf
->hash_locks
+ hash
);
100 spin_lock(&conf
->device_lock
);
103 static inline void unlock_device_hash_lock(struct r5conf
*conf
, int hash
)
105 spin_unlock(&conf
->device_lock
);
106 spin_unlock_irq(conf
->hash_locks
+ hash
);
109 static inline void lock_all_device_hash_locks_irq(struct r5conf
*conf
)
113 spin_lock(conf
->hash_locks
);
114 for (i
= 1; i
< NR_STRIPE_HASH_LOCKS
; i
++)
115 spin_lock_nest_lock(conf
->hash_locks
+ i
, conf
->hash_locks
);
116 spin_lock(&conf
->device_lock
);
119 static inline void unlock_all_device_hash_locks_irq(struct r5conf
*conf
)
122 spin_unlock(&conf
->device_lock
);
123 for (i
= NR_STRIPE_HASH_LOCKS
; i
; i
--)
124 spin_unlock(conf
->hash_locks
+ i
- 1);
128 /* bio's attached to a stripe+device for I/O are linked together in bi_sector
129 * order without overlap. There may be several bio's per stripe+device, and
130 * a bio could span several devices.
131 * When walking this list for a particular stripe+device, we must never proceed
132 * beyond a bio that extends past this device, as the next bio might no longer
134 * This function is used to determine the 'next' bio in the list, given the sector
135 * of the current stripe+device
137 static inline struct bio
*r5_next_bio(struct bio
*bio
, sector_t sector
)
139 int sectors
= bio_sectors(bio
);
140 if (bio
->bi_iter
.bi_sector
+ sectors
< sector
+ STRIPE_SECTORS
)
147 * We maintain a biased count of active stripes in the bottom 16 bits of
148 * bi_phys_segments, and a count of processed stripes in the upper 16 bits
150 static inline int raid5_bi_processed_stripes(struct bio
*bio
)
152 atomic_t
*segments
= (atomic_t
*)&bio
->bi_phys_segments
;
153 return (atomic_read(segments
) >> 16) & 0xffff;
156 static inline int raid5_dec_bi_active_stripes(struct bio
*bio
)
158 atomic_t
*segments
= (atomic_t
*)&bio
->bi_phys_segments
;
159 return atomic_sub_return(1, segments
) & 0xffff;
162 static inline void raid5_inc_bi_active_stripes(struct bio
*bio
)
164 atomic_t
*segments
= (atomic_t
*)&bio
->bi_phys_segments
;
165 atomic_inc(segments
);
168 static inline void raid5_set_bi_processed_stripes(struct bio
*bio
,
171 atomic_t
*segments
= (atomic_t
*)&bio
->bi_phys_segments
;
175 old
= atomic_read(segments
);
176 new = (old
& 0xffff) | (cnt
<< 16);
177 } while (atomic_cmpxchg(segments
, old
, new) != old
);
180 static inline void raid5_set_bi_stripes(struct bio
*bio
, unsigned int cnt
)
182 atomic_t
*segments
= (atomic_t
*)&bio
->bi_phys_segments
;
183 atomic_set(segments
, cnt
);
186 /* Find first data disk in a raid6 stripe */
187 static inline int raid6_d0(struct stripe_head
*sh
)
190 /* ddf always start from first device */
192 /* md starts just after Q block */
193 if (sh
->qd_idx
== sh
->disks
- 1)
196 return sh
->qd_idx
+ 1;
198 static inline int raid6_next_disk(int disk
, int raid_disks
)
201 return (disk
< raid_disks
) ? disk
: 0;
204 /* When walking through the disks in a raid5, starting at raid6_d0,
205 * We need to map each disk to a 'slot', where the data disks are slot
206 * 0 .. raid_disks-3, the parity disk is raid_disks-2 and the Q disk
207 * is raid_disks-1. This help does that mapping.
209 static int raid6_idx_to_slot(int idx
, struct stripe_head
*sh
,
210 int *count
, int syndrome_disks
)
216 if (idx
== sh
->pd_idx
)
217 return syndrome_disks
;
218 if (idx
== sh
->qd_idx
)
219 return syndrome_disks
+ 1;
225 static void return_io(struct bio
*return_bi
)
227 struct bio
*bi
= return_bi
;
230 return_bi
= bi
->bi_next
;
232 bi
->bi_iter
.bi_size
= 0;
233 trace_block_bio_complete(bdev_get_queue(bi
->bi_bdev
),
240 static void print_raid5_conf (struct r5conf
*conf
);
242 static int stripe_operations_active(struct stripe_head
*sh
)
244 return sh
->check_state
|| sh
->reconstruct_state
||
245 test_bit(STRIPE_BIOFILL_RUN
, &sh
->state
) ||
246 test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
249 static void raid5_wakeup_stripe_thread(struct stripe_head
*sh
)
251 struct r5conf
*conf
= sh
->raid_conf
;
252 struct r5worker_group
*group
;
254 int i
, cpu
= sh
->cpu
;
256 if (!cpu_online(cpu
)) {
257 cpu
= cpumask_any(cpu_online_mask
);
261 if (list_empty(&sh
->lru
)) {
262 struct r5worker_group
*group
;
263 group
= conf
->worker_groups
+ cpu_to_group(cpu
);
264 list_add_tail(&sh
->lru
, &group
->handle_list
);
265 group
->stripes_cnt
++;
269 if (conf
->worker_cnt_per_group
== 0) {
270 md_wakeup_thread(conf
->mddev
->thread
);
274 group
= conf
->worker_groups
+ cpu_to_group(sh
->cpu
);
276 group
->workers
[0].working
= true;
277 /* at least one worker should run to avoid race */
278 queue_work_on(sh
->cpu
, raid5_wq
, &group
->workers
[0].work
);
280 thread_cnt
= group
->stripes_cnt
/ MAX_STRIPE_BATCH
- 1;
281 /* wakeup more workers */
282 for (i
= 1; i
< conf
->worker_cnt_per_group
&& thread_cnt
> 0; i
++) {
283 if (group
->workers
[i
].working
== false) {
284 group
->workers
[i
].working
= true;
285 queue_work_on(sh
->cpu
, raid5_wq
,
286 &group
->workers
[i
].work
);
292 static void do_release_stripe(struct r5conf
*conf
, struct stripe_head
*sh
,
293 struct list_head
*temp_inactive_list
)
295 BUG_ON(!list_empty(&sh
->lru
));
296 BUG_ON(atomic_read(&conf
->active_stripes
)==0);
297 if (test_bit(STRIPE_HANDLE
, &sh
->state
)) {
298 if (test_bit(STRIPE_DELAYED
, &sh
->state
) &&
299 !test_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
)) {
300 list_add_tail(&sh
->lru
, &conf
->delayed_list
);
301 if (atomic_read(&conf
->preread_active_stripes
)
303 md_wakeup_thread(conf
->mddev
->thread
);
304 } else if (test_bit(STRIPE_BIT_DELAY
, &sh
->state
) &&
305 sh
->bm_seq
- conf
->seq_write
> 0)
306 list_add_tail(&sh
->lru
, &conf
->bitmap_list
);
308 clear_bit(STRIPE_DELAYED
, &sh
->state
);
309 clear_bit(STRIPE_BIT_DELAY
, &sh
->state
);
310 if (conf
->worker_cnt_per_group
== 0) {
311 list_add_tail(&sh
->lru
, &conf
->handle_list
);
313 raid5_wakeup_stripe_thread(sh
);
317 md_wakeup_thread(conf
->mddev
->thread
);
319 BUG_ON(stripe_operations_active(sh
));
320 if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
321 if (atomic_dec_return(&conf
->preread_active_stripes
)
323 md_wakeup_thread(conf
->mddev
->thread
);
324 atomic_dec(&conf
->active_stripes
);
325 if (!test_bit(STRIPE_EXPANDING
, &sh
->state
))
326 list_add_tail(&sh
->lru
, temp_inactive_list
);
330 static void __release_stripe(struct r5conf
*conf
, struct stripe_head
*sh
,
331 struct list_head
*temp_inactive_list
)
333 if (atomic_dec_and_test(&sh
->count
))
334 do_release_stripe(conf
, sh
, temp_inactive_list
);
338 * @hash could be NR_STRIPE_HASH_LOCKS, then we have a list of inactive_list
340 * Be careful: Only one task can add/delete stripes from temp_inactive_list at
341 * given time. Adding stripes only takes device lock, while deleting stripes
342 * only takes hash lock.
344 static void release_inactive_stripe_list(struct r5conf
*conf
,
345 struct list_head
*temp_inactive_list
,
349 bool do_wakeup
= false;
352 if (hash
== NR_STRIPE_HASH_LOCKS
) {
353 size
= NR_STRIPE_HASH_LOCKS
;
354 hash
= NR_STRIPE_HASH_LOCKS
- 1;
358 struct list_head
*list
= &temp_inactive_list
[size
- 1];
361 * We don't hold any lock here yet, get_active_stripe() might
362 * remove stripes from the list
364 if (!list_empty_careful(list
)) {
365 spin_lock_irqsave(conf
->hash_locks
+ hash
, flags
);
366 if (list_empty(conf
->inactive_list
+ hash
) &&
368 atomic_dec(&conf
->empty_inactive_list_nr
);
369 list_splice_tail_init(list
, conf
->inactive_list
+ hash
);
371 spin_unlock_irqrestore(conf
->hash_locks
+ hash
, flags
);
378 wake_up(&conf
->wait_for_stripe
);
379 if (conf
->retry_read_aligned
)
380 md_wakeup_thread(conf
->mddev
->thread
);
384 /* should hold conf->device_lock already */
385 static int release_stripe_list(struct r5conf
*conf
,
386 struct list_head
*temp_inactive_list
)
388 struct stripe_head
*sh
;
390 struct llist_node
*head
;
392 head
= llist_del_all(&conf
->released_stripes
);
393 head
= llist_reverse_order(head
);
397 sh
= llist_entry(head
, struct stripe_head
, release_list
);
398 head
= llist_next(head
);
399 /* sh could be readded after STRIPE_ON_RELEASE_LIST is cleard */
401 clear_bit(STRIPE_ON_RELEASE_LIST
, &sh
->state
);
403 * Don't worry the bit is set here, because if the bit is set
404 * again, the count is always > 1. This is true for
405 * STRIPE_ON_UNPLUG_LIST bit too.
407 hash
= sh
->hash_lock_index
;
408 __release_stripe(conf
, sh
, &temp_inactive_list
[hash
]);
415 static void release_stripe(struct stripe_head
*sh
)
417 struct r5conf
*conf
= sh
->raid_conf
;
419 struct list_head list
;
423 /* Avoid release_list until the last reference.
425 if (atomic_add_unless(&sh
->count
, -1, 1))
428 if (unlikely(!conf
->mddev
->thread
) ||
429 test_and_set_bit(STRIPE_ON_RELEASE_LIST
, &sh
->state
))
431 wakeup
= llist_add(&sh
->release_list
, &conf
->released_stripes
);
433 md_wakeup_thread(conf
->mddev
->thread
);
436 local_irq_save(flags
);
437 /* we are ok here if STRIPE_ON_RELEASE_LIST is set or not */
438 if (atomic_dec_and_lock(&sh
->count
, &conf
->device_lock
)) {
439 INIT_LIST_HEAD(&list
);
440 hash
= sh
->hash_lock_index
;
441 do_release_stripe(conf
, sh
, &list
);
442 spin_unlock(&conf
->device_lock
);
443 release_inactive_stripe_list(conf
, &list
, hash
);
445 local_irq_restore(flags
);
448 static inline void remove_hash(struct stripe_head
*sh
)
450 pr_debug("remove_hash(), stripe %llu\n",
451 (unsigned long long)sh
->sector
);
453 hlist_del_init(&sh
->hash
);
456 static inline void insert_hash(struct r5conf
*conf
, struct stripe_head
*sh
)
458 struct hlist_head
*hp
= stripe_hash(conf
, sh
->sector
);
460 pr_debug("insert_hash(), stripe %llu\n",
461 (unsigned long long)sh
->sector
);
463 hlist_add_head(&sh
->hash
, hp
);
466 /* find an idle stripe, make sure it is unhashed, and return it. */
467 static struct stripe_head
*get_free_stripe(struct r5conf
*conf
, int hash
)
469 struct stripe_head
*sh
= NULL
;
470 struct list_head
*first
;
472 if (list_empty(conf
->inactive_list
+ hash
))
474 first
= (conf
->inactive_list
+ hash
)->next
;
475 sh
= list_entry(first
, struct stripe_head
, lru
);
476 list_del_init(first
);
478 atomic_inc(&conf
->active_stripes
);
479 BUG_ON(hash
!= sh
->hash_lock_index
);
480 if (list_empty(conf
->inactive_list
+ hash
))
481 atomic_inc(&conf
->empty_inactive_list_nr
);
486 static void shrink_buffers(struct stripe_head
*sh
)
490 int num
= sh
->raid_conf
->pool_size
;
492 for (i
= 0; i
< num
; i
++) {
493 WARN_ON(sh
->dev
[i
].page
!= sh
->dev
[i
].orig_page
);
497 sh
->dev
[i
].page
= NULL
;
502 static int grow_buffers(struct stripe_head
*sh
)
505 int num
= sh
->raid_conf
->pool_size
;
507 for (i
= 0; i
< num
; i
++) {
510 if (!(page
= alloc_page(GFP_KERNEL
))) {
513 sh
->dev
[i
].page
= page
;
514 sh
->dev
[i
].orig_page
= page
;
519 static void raid5_build_block(struct stripe_head
*sh
, int i
, int previous
);
520 static void stripe_set_idx(sector_t stripe
, struct r5conf
*conf
, int previous
,
521 struct stripe_head
*sh
);
523 static void init_stripe(struct stripe_head
*sh
, sector_t sector
, int previous
)
525 struct r5conf
*conf
= sh
->raid_conf
;
528 BUG_ON(atomic_read(&sh
->count
) != 0);
529 BUG_ON(test_bit(STRIPE_HANDLE
, &sh
->state
));
530 BUG_ON(stripe_operations_active(sh
));
532 pr_debug("init_stripe called, stripe %llu\n",
533 (unsigned long long)sector
);
535 seq
= read_seqcount_begin(&conf
->gen_lock
);
536 sh
->generation
= conf
->generation
- previous
;
537 sh
->disks
= previous
? conf
->previous_raid_disks
: conf
->raid_disks
;
539 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
,
1349 static void ops_complete_prexor(void *stripe_head_ref
)
1351 struct stripe_head
*sh
= stripe_head_ref
;
1353 pr_debug("%s: stripe %llu\n", __func__
,
1354 (unsigned long long)sh
->sector
);
1357 static struct dma_async_tx_descriptor
*
1358 ops_run_prexor(struct stripe_head
*sh
, struct raid5_percpu
*percpu
,
1359 struct dma_async_tx_descriptor
*tx
)
1361 int disks
= sh
->disks
;
1362 struct page
**xor_srcs
= percpu
->scribble
;
1363 int count
= 0, pd_idx
= sh
->pd_idx
, i
;
1364 struct async_submit_ctl submit
;
1366 /* existing parity data subtracted */
1367 struct page
*xor_dest
= xor_srcs
[count
++] = sh
->dev
[pd_idx
].page
;
1369 pr_debug("%s: stripe %llu\n", __func__
,
1370 (unsigned long long)sh
->sector
);
1372 for (i
= disks
; i
--; ) {
1373 struct r5dev
*dev
= &sh
->dev
[i
];
1374 /* Only process blocks that are known to be uptodate */
1375 if (test_bit(R5_Wantdrain
, &dev
->flags
))
1376 xor_srcs
[count
++] = dev
->page
;
1379 init_async_submit(&submit
, ASYNC_TX_FENCE
|ASYNC_TX_XOR_DROP_DST
, tx
,
1380 ops_complete_prexor
, sh
, to_addr_conv(sh
, percpu
));
1381 tx
= async_xor(xor_dest
, xor_srcs
, 0, count
, STRIPE_SIZE
, &submit
);
1386 static struct dma_async_tx_descriptor
*
1387 ops_run_biodrain(struct stripe_head
*sh
, struct dma_async_tx_descriptor
*tx
)
1389 int disks
= sh
->disks
;
1392 pr_debug("%s: stripe %llu\n", __func__
,
1393 (unsigned long long)sh
->sector
);
1395 for (i
= disks
; i
--; ) {
1396 struct r5dev
*dev
= &sh
->dev
[i
];
1399 if (test_and_clear_bit(R5_Wantdrain
, &dev
->flags
)) {
1402 spin_lock_irq(&sh
->stripe_lock
);
1403 chosen
= dev
->towrite
;
1404 dev
->towrite
= NULL
;
1405 BUG_ON(dev
->written
);
1406 wbi
= dev
->written
= chosen
;
1407 spin_unlock_irq(&sh
->stripe_lock
);
1408 WARN_ON(dev
->page
!= dev
->orig_page
);
1410 while (wbi
&& wbi
->bi_iter
.bi_sector
<
1411 dev
->sector
+ STRIPE_SECTORS
) {
1412 if (wbi
->bi_rw
& REQ_FUA
)
1413 set_bit(R5_WantFUA
, &dev
->flags
);
1414 if (wbi
->bi_rw
& REQ_SYNC
)
1415 set_bit(R5_SyncIO
, &dev
->flags
);
1416 if (wbi
->bi_rw
& REQ_DISCARD
)
1417 set_bit(R5_Discard
, &dev
->flags
);
1419 tx
= async_copy_data(1, wbi
, &dev
->page
,
1420 dev
->sector
, tx
, sh
);
1421 if (dev
->page
!= dev
->orig_page
) {
1422 set_bit(R5_SkipCopy
, &dev
->flags
);
1423 clear_bit(R5_UPTODATE
, &dev
->flags
);
1424 clear_bit(R5_OVERWRITE
, &dev
->flags
);
1427 wbi
= r5_next_bio(wbi
, dev
->sector
);
1435 static void ops_complete_reconstruct(void *stripe_head_ref
)
1437 struct stripe_head
*sh
= stripe_head_ref
;
1438 int disks
= sh
->disks
;
1439 int pd_idx
= sh
->pd_idx
;
1440 int qd_idx
= sh
->qd_idx
;
1442 bool fua
= false, sync
= false, discard
= false;
1444 pr_debug("%s: stripe %llu\n", __func__
,
1445 (unsigned long long)sh
->sector
);
1447 for (i
= disks
; i
--; ) {
1448 fua
|= test_bit(R5_WantFUA
, &sh
->dev
[i
].flags
);
1449 sync
|= test_bit(R5_SyncIO
, &sh
->dev
[i
].flags
);
1450 discard
|= test_bit(R5_Discard
, &sh
->dev
[i
].flags
);
1453 for (i
= disks
; i
--; ) {
1454 struct r5dev
*dev
= &sh
->dev
[i
];
1456 if (dev
->written
|| i
== pd_idx
|| i
== qd_idx
) {
1457 if (!discard
&& !test_bit(R5_SkipCopy
, &dev
->flags
))
1458 set_bit(R5_UPTODATE
, &dev
->flags
);
1460 set_bit(R5_WantFUA
, &dev
->flags
);
1462 set_bit(R5_SyncIO
, &dev
->flags
);
1466 if (sh
->reconstruct_state
== reconstruct_state_drain_run
)
1467 sh
->reconstruct_state
= reconstruct_state_drain_result
;
1468 else if (sh
->reconstruct_state
== reconstruct_state_prexor_drain_run
)
1469 sh
->reconstruct_state
= reconstruct_state_prexor_drain_result
;
1471 BUG_ON(sh
->reconstruct_state
!= reconstruct_state_run
);
1472 sh
->reconstruct_state
= reconstruct_state_result
;
1475 set_bit(STRIPE_HANDLE
, &sh
->state
);
1480 ops_run_reconstruct5(struct stripe_head
*sh
, struct raid5_percpu
*percpu
,
1481 struct dma_async_tx_descriptor
*tx
)
1483 int disks
= sh
->disks
;
1484 struct page
**xor_srcs
= percpu
->scribble
;
1485 struct async_submit_ctl submit
;
1486 int count
= 0, pd_idx
= sh
->pd_idx
, i
;
1487 struct page
*xor_dest
;
1489 unsigned long flags
;
1491 pr_debug("%s: stripe %llu\n", __func__
,
1492 (unsigned long long)sh
->sector
);
1494 for (i
= 0; i
< sh
->disks
; i
++) {
1497 if (!test_bit(R5_Discard
, &sh
->dev
[i
].flags
))
1500 if (i
>= sh
->disks
) {
1501 atomic_inc(&sh
->count
);
1502 set_bit(R5_Discard
, &sh
->dev
[pd_idx
].flags
);
1503 ops_complete_reconstruct(sh
);
1506 /* check if prexor is active which means only process blocks
1507 * that are part of a read-modify-write (written)
1509 if (sh
->reconstruct_state
== reconstruct_state_prexor_drain_run
) {
1511 xor_dest
= xor_srcs
[count
++] = sh
->dev
[pd_idx
].page
;
1512 for (i
= disks
; i
--; ) {
1513 struct r5dev
*dev
= &sh
->dev
[i
];
1515 xor_srcs
[count
++] = dev
->page
;
1518 xor_dest
= sh
->dev
[pd_idx
].page
;
1519 for (i
= disks
; i
--; ) {
1520 struct r5dev
*dev
= &sh
->dev
[i
];
1522 xor_srcs
[count
++] = dev
->page
;
1526 /* 1/ if we prexor'd then the dest is reused as a source
1527 * 2/ if we did not prexor then we are redoing the parity
1528 * set ASYNC_TX_XOR_DROP_DST and ASYNC_TX_XOR_ZERO_DST
1529 * for the synchronous xor case
1531 flags
= ASYNC_TX_ACK
|
1532 (prexor
? ASYNC_TX_XOR_DROP_DST
: ASYNC_TX_XOR_ZERO_DST
);
1534 atomic_inc(&sh
->count
);
1536 init_async_submit(&submit
, flags
, tx
, ops_complete_reconstruct
, sh
,
1537 to_addr_conv(sh
, percpu
));
1538 if (unlikely(count
== 1))
1539 tx
= async_memcpy(xor_dest
, xor_srcs
[0], 0, 0, STRIPE_SIZE
, &submit
);
1541 tx
= async_xor(xor_dest
, xor_srcs
, 0, count
, STRIPE_SIZE
, &submit
);
1545 ops_run_reconstruct6(struct stripe_head
*sh
, struct raid5_percpu
*percpu
,
1546 struct dma_async_tx_descriptor
*tx
)
1548 struct async_submit_ctl submit
;
1549 struct page
**blocks
= percpu
->scribble
;
1552 pr_debug("%s: stripe %llu\n", __func__
, (unsigned long long)sh
->sector
);
1554 for (i
= 0; i
< sh
->disks
; i
++) {
1555 if (sh
->pd_idx
== i
|| sh
->qd_idx
== i
)
1557 if (!test_bit(R5_Discard
, &sh
->dev
[i
].flags
))
1560 if (i
>= sh
->disks
) {
1561 atomic_inc(&sh
->count
);
1562 set_bit(R5_Discard
, &sh
->dev
[sh
->pd_idx
].flags
);
1563 set_bit(R5_Discard
, &sh
->dev
[sh
->qd_idx
].flags
);
1564 ops_complete_reconstruct(sh
);
1568 count
= set_syndrome_sources(blocks
, sh
);
1570 atomic_inc(&sh
->count
);
1572 init_async_submit(&submit
, ASYNC_TX_ACK
, tx
, ops_complete_reconstruct
,
1573 sh
, to_addr_conv(sh
, percpu
));
1574 async_gen_syndrome(blocks
, 0, count
+2, STRIPE_SIZE
, &submit
);
1577 static void ops_complete_check(void *stripe_head_ref
)
1579 struct stripe_head
*sh
= stripe_head_ref
;
1581 pr_debug("%s: stripe %llu\n", __func__
,
1582 (unsigned long long)sh
->sector
);
1584 sh
->check_state
= check_state_check_result
;
1585 set_bit(STRIPE_HANDLE
, &sh
->state
);
1589 static void ops_run_check_p(struct stripe_head
*sh
, struct raid5_percpu
*percpu
)
1591 int disks
= sh
->disks
;
1592 int pd_idx
= sh
->pd_idx
;
1593 int qd_idx
= sh
->qd_idx
;
1594 struct page
*xor_dest
;
1595 struct page
**xor_srcs
= percpu
->scribble
;
1596 struct dma_async_tx_descriptor
*tx
;
1597 struct async_submit_ctl submit
;
1601 pr_debug("%s: stripe %llu\n", __func__
,
1602 (unsigned long long)sh
->sector
);
1605 xor_dest
= sh
->dev
[pd_idx
].page
;
1606 xor_srcs
[count
++] = xor_dest
;
1607 for (i
= disks
; i
--; ) {
1608 if (i
== pd_idx
|| i
== qd_idx
)
1610 xor_srcs
[count
++] = sh
->dev
[i
].page
;
1613 init_async_submit(&submit
, 0, NULL
, NULL
, NULL
,
1614 to_addr_conv(sh
, percpu
));
1615 tx
= async_xor_val(xor_dest
, xor_srcs
, 0, count
, STRIPE_SIZE
,
1616 &sh
->ops
.zero_sum_result
, &submit
);
1618 atomic_inc(&sh
->count
);
1619 init_async_submit(&submit
, ASYNC_TX_ACK
, tx
, ops_complete_check
, sh
, NULL
);
1620 tx
= async_trigger_callback(&submit
);
1623 static void ops_run_check_pq(struct stripe_head
*sh
, struct raid5_percpu
*percpu
, int checkp
)
1625 struct page
**srcs
= percpu
->scribble
;
1626 struct async_submit_ctl submit
;
1629 pr_debug("%s: stripe %llu checkp: %d\n", __func__
,
1630 (unsigned long long)sh
->sector
, checkp
);
1632 count
= set_syndrome_sources(srcs
, sh
);
1636 atomic_inc(&sh
->count
);
1637 init_async_submit(&submit
, ASYNC_TX_ACK
, NULL
, ops_complete_check
,
1638 sh
, to_addr_conv(sh
, percpu
));
1639 async_syndrome_val(srcs
, 0, count
+2, STRIPE_SIZE
,
1640 &sh
->ops
.zero_sum_result
, percpu
->spare_page
, &submit
);
1643 static void raid_run_ops(struct stripe_head
*sh
, unsigned long ops_request
)
1645 int overlap_clear
= 0, i
, disks
= sh
->disks
;
1646 struct dma_async_tx_descriptor
*tx
= NULL
;
1647 struct r5conf
*conf
= sh
->raid_conf
;
1648 int level
= conf
->level
;
1649 struct raid5_percpu
*percpu
;
1653 percpu
= per_cpu_ptr(conf
->percpu
, cpu
);
1654 if (test_bit(STRIPE_OP_BIOFILL
, &ops_request
)) {
1655 ops_run_biofill(sh
);
1659 if (test_bit(STRIPE_OP_COMPUTE_BLK
, &ops_request
)) {
1661 tx
= ops_run_compute5(sh
, percpu
);
1663 if (sh
->ops
.target2
< 0 || sh
->ops
.target
< 0)
1664 tx
= ops_run_compute6_1(sh
, percpu
);
1666 tx
= ops_run_compute6_2(sh
, percpu
);
1668 /* terminate the chain if reconstruct is not set to be run */
1669 if (tx
&& !test_bit(STRIPE_OP_RECONSTRUCT
, &ops_request
))
1673 if (test_bit(STRIPE_OP_PREXOR
, &ops_request
))
1674 tx
= ops_run_prexor(sh
, percpu
, tx
);
1676 if (test_bit(STRIPE_OP_BIODRAIN
, &ops_request
)) {
1677 tx
= ops_run_biodrain(sh
, tx
);
1681 if (test_bit(STRIPE_OP_RECONSTRUCT
, &ops_request
)) {
1683 ops_run_reconstruct5(sh
, percpu
, tx
);
1685 ops_run_reconstruct6(sh
, percpu
, tx
);
1688 if (test_bit(STRIPE_OP_CHECK
, &ops_request
)) {
1689 if (sh
->check_state
== check_state_run
)
1690 ops_run_check_p(sh
, percpu
);
1691 else if (sh
->check_state
== check_state_run_q
)
1692 ops_run_check_pq(sh
, percpu
, 0);
1693 else if (sh
->check_state
== check_state_run_pq
)
1694 ops_run_check_pq(sh
, percpu
, 1);
1700 for (i
= disks
; i
--; ) {
1701 struct r5dev
*dev
= &sh
->dev
[i
];
1702 if (test_and_clear_bit(R5_Overlap
, &dev
->flags
))
1703 wake_up(&sh
->raid_conf
->wait_for_overlap
);
1708 static int grow_one_stripe(struct r5conf
*conf
, int hash
)
1710 struct stripe_head
*sh
;
1711 sh
= kmem_cache_zalloc(conf
->slab_cache
, GFP_KERNEL
);
1715 sh
->raid_conf
= conf
;
1717 spin_lock_init(&sh
->stripe_lock
);
1719 if (grow_buffers(sh
)) {
1721 kmem_cache_free(conf
->slab_cache
, sh
);
1724 sh
->hash_lock_index
= hash
;
1725 /* we just created an active stripe so... */
1726 atomic_set(&sh
->count
, 1);
1727 atomic_inc(&conf
->active_stripes
);
1728 INIT_LIST_HEAD(&sh
->lru
);
1733 static int grow_stripes(struct r5conf
*conf
, int num
)
1735 struct kmem_cache
*sc
;
1736 int devs
= max(conf
->raid_disks
, conf
->previous_raid_disks
);
1739 if (conf
->mddev
->gendisk
)
1740 sprintf(conf
->cache_name
[0],
1741 "raid%d-%s", conf
->level
, mdname(conf
->mddev
));
1743 sprintf(conf
->cache_name
[0],
1744 "raid%d-%p", conf
->level
, conf
->mddev
);
1745 sprintf(conf
->cache_name
[1], "%s-alt", conf
->cache_name
[0]);
1747 conf
->active_name
= 0;
1748 sc
= kmem_cache_create(conf
->cache_name
[conf
->active_name
],
1749 sizeof(struct stripe_head
)+(devs
-1)*sizeof(struct r5dev
),
1753 conf
->slab_cache
= sc
;
1754 conf
->pool_size
= devs
;
1755 hash
= conf
->max_nr_stripes
% NR_STRIPE_HASH_LOCKS
;
1757 if (!grow_one_stripe(conf
, hash
))
1759 conf
->max_nr_stripes
++;
1760 hash
= (hash
+ 1) % NR_STRIPE_HASH_LOCKS
;
1766 * scribble_len - return the required size of the scribble region
1767 * @num - total number of disks in the array
1769 * The size must be enough to contain:
1770 * 1/ a struct page pointer for each device in the array +2
1771 * 2/ room to convert each entry in (1) to its corresponding dma
1772 * (dma_map_page()) or page (page_address()) address.
1774 * Note: the +2 is for the destination buffers of the ddf/raid6 case where we
1775 * calculate over all devices (not just the data blocks), using zeros in place
1776 * of the P and Q blocks.
1778 static size_t scribble_len(int num
)
1782 len
= sizeof(struct page
*) * (num
+2) + sizeof(addr_conv_t
) * (num
+2);
1787 static int resize_stripes(struct r5conf
*conf
, int newsize
)
1789 /* Make all the stripes able to hold 'newsize' devices.
1790 * New slots in each stripe get 'page' set to a new page.
1792 * This happens in stages:
1793 * 1/ create a new kmem_cache and allocate the required number of
1795 * 2/ gather all the old stripe_heads and transfer the pages across
1796 * to the new stripe_heads. This will have the side effect of
1797 * freezing the array as once all stripe_heads have been collected,
1798 * no IO will be possible. Old stripe heads are freed once their
1799 * pages have been transferred over, and the old kmem_cache is
1800 * freed when all stripes are done.
1801 * 3/ reallocate conf->disks to be suitable bigger. If this fails,
1802 * we simple return a failre status - no need to clean anything up.
1803 * 4/ allocate new pages for the new slots in the new stripe_heads.
1804 * If this fails, we don't bother trying the shrink the
1805 * stripe_heads down again, we just leave them as they are.
1806 * As each stripe_head is processed the new one is released into
1809 * Once step2 is started, we cannot afford to wait for a write,
1810 * so we use GFP_NOIO allocations.
1812 struct stripe_head
*osh
, *nsh
;
1813 LIST_HEAD(newstripes
);
1814 struct disk_info
*ndisks
;
1817 struct kmem_cache
*sc
;
1821 if (newsize
<= conf
->pool_size
)
1822 return 0; /* never bother to shrink */
1824 err
= md_allow_write(conf
->mddev
);
1829 sc
= kmem_cache_create(conf
->cache_name
[1-conf
->active_name
],
1830 sizeof(struct stripe_head
)+(newsize
-1)*sizeof(struct r5dev
),
1835 for (i
= conf
->max_nr_stripes
; i
; i
--) {
1836 nsh
= kmem_cache_zalloc(sc
, GFP_KERNEL
);
1840 nsh
->raid_conf
= conf
;
1841 spin_lock_init(&nsh
->stripe_lock
);
1843 list_add(&nsh
->lru
, &newstripes
);
1846 /* didn't get enough, give up */
1847 while (!list_empty(&newstripes
)) {
1848 nsh
= list_entry(newstripes
.next
, struct stripe_head
, lru
);
1849 list_del(&nsh
->lru
);
1850 kmem_cache_free(sc
, nsh
);
1852 kmem_cache_destroy(sc
);
1855 /* Step 2 - Must use GFP_NOIO now.
1856 * OK, we have enough stripes, start collecting inactive
1857 * stripes and copying them over
1861 list_for_each_entry(nsh
, &newstripes
, lru
) {
1862 lock_device_hash_lock(conf
, hash
);
1863 wait_event_cmd(conf
->wait_for_stripe
,
1864 !list_empty(conf
->inactive_list
+ hash
),
1865 unlock_device_hash_lock(conf
, hash
),
1866 lock_device_hash_lock(conf
, hash
));
1867 osh
= get_free_stripe(conf
, hash
);
1868 unlock_device_hash_lock(conf
, hash
);
1869 atomic_set(&nsh
->count
, 1);
1870 for(i
=0; i
<conf
->pool_size
; i
++) {
1871 nsh
->dev
[i
].page
= osh
->dev
[i
].page
;
1872 nsh
->dev
[i
].orig_page
= osh
->dev
[i
].page
;
1874 for( ; i
<newsize
; i
++)
1875 nsh
->dev
[i
].page
= NULL
;
1876 nsh
->hash_lock_index
= hash
;
1877 kmem_cache_free(conf
->slab_cache
, osh
);
1879 if (cnt
>= conf
->max_nr_stripes
/ NR_STRIPE_HASH_LOCKS
+
1880 !!((conf
->max_nr_stripes
% NR_STRIPE_HASH_LOCKS
) > hash
)) {
1885 kmem_cache_destroy(conf
->slab_cache
);
1888 * At this point, we are holding all the stripes so the array
1889 * is completely stalled, so now is a good time to resize
1890 * conf->disks and the scribble region
1892 ndisks
= kzalloc(newsize
* sizeof(struct disk_info
), GFP_NOIO
);
1894 for (i
=0; i
<conf
->raid_disks
; i
++)
1895 ndisks
[i
] = conf
->disks
[i
];
1897 conf
->disks
= ndisks
;
1902 conf
->scribble_len
= scribble_len(newsize
);
1903 for_each_present_cpu(cpu
) {
1904 struct raid5_percpu
*percpu
;
1907 percpu
= per_cpu_ptr(conf
->percpu
, cpu
);
1908 scribble
= kmalloc(conf
->scribble_len
, GFP_NOIO
);
1911 kfree(percpu
->scribble
);
1912 percpu
->scribble
= scribble
;
1920 /* Step 4, return new stripes to service */
1921 while(!list_empty(&newstripes
)) {
1922 nsh
= list_entry(newstripes
.next
, struct stripe_head
, lru
);
1923 list_del_init(&nsh
->lru
);
1925 for (i
=conf
->raid_disks
; i
< newsize
; i
++)
1926 if (nsh
->dev
[i
].page
== NULL
) {
1927 struct page
*p
= alloc_page(GFP_NOIO
);
1928 nsh
->dev
[i
].page
= p
;
1929 nsh
->dev
[i
].orig_page
= p
;
1933 release_stripe(nsh
);
1935 /* critical section pass, GFP_NOIO no longer needed */
1937 conf
->slab_cache
= sc
;
1938 conf
->active_name
= 1-conf
->active_name
;
1939 conf
->pool_size
= newsize
;
1943 static int drop_one_stripe(struct r5conf
*conf
, int hash
)
1945 struct stripe_head
*sh
;
1947 spin_lock_irq(conf
->hash_locks
+ hash
);
1948 sh
= get_free_stripe(conf
, hash
);
1949 spin_unlock_irq(conf
->hash_locks
+ hash
);
1952 BUG_ON(atomic_read(&sh
->count
));
1954 kmem_cache_free(conf
->slab_cache
, sh
);
1955 atomic_dec(&conf
->active_stripes
);
1959 static void shrink_stripes(struct r5conf
*conf
)
1962 for (hash
= 0; hash
< NR_STRIPE_HASH_LOCKS
; hash
++)
1963 while (drop_one_stripe(conf
, hash
))
1966 if (conf
->slab_cache
)
1967 kmem_cache_destroy(conf
->slab_cache
);
1968 conf
->slab_cache
= NULL
;
1971 static void raid5_end_read_request(struct bio
* bi
, int error
)
1973 struct stripe_head
*sh
= bi
->bi_private
;
1974 struct r5conf
*conf
= sh
->raid_conf
;
1975 int disks
= sh
->disks
, i
;
1976 int uptodate
= test_bit(BIO_UPTODATE
, &bi
->bi_flags
);
1977 char b
[BDEVNAME_SIZE
];
1978 struct md_rdev
*rdev
= NULL
;
1981 for (i
=0 ; i
<disks
; i
++)
1982 if (bi
== &sh
->dev
[i
].req
)
1985 pr_debug("end_read_request %llu/%d, count: %d, uptodate %d.\n",
1986 (unsigned long long)sh
->sector
, i
, atomic_read(&sh
->count
),
1992 if (test_bit(R5_ReadRepl
, &sh
->dev
[i
].flags
))
1993 /* If replacement finished while this request was outstanding,
1994 * 'replacement' might be NULL already.
1995 * In that case it moved down to 'rdev'.
1996 * rdev is not removed until all requests are finished.
1998 rdev
= conf
->disks
[i
].replacement
;
2000 rdev
= conf
->disks
[i
].rdev
;
2002 if (use_new_offset(conf
, sh
))
2003 s
= sh
->sector
+ rdev
->new_data_offset
;
2005 s
= sh
->sector
+ rdev
->data_offset
;
2007 set_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
);
2008 if (test_bit(R5_ReadError
, &sh
->dev
[i
].flags
)) {
2009 /* Note that this cannot happen on a
2010 * replacement device. We just fail those on
2015 "md/raid:%s: read error corrected"
2016 " (%lu sectors at %llu on %s)\n",
2017 mdname(conf
->mddev
), STRIPE_SECTORS
,
2018 (unsigned long long)s
,
2019 bdevname(rdev
->bdev
, b
));
2020 atomic_add(STRIPE_SECTORS
, &rdev
->corrected_errors
);
2021 clear_bit(R5_ReadError
, &sh
->dev
[i
].flags
);
2022 clear_bit(R5_ReWrite
, &sh
->dev
[i
].flags
);
2023 } else if (test_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
))
2024 clear_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
);
2026 if (atomic_read(&rdev
->read_errors
))
2027 atomic_set(&rdev
->read_errors
, 0);
2029 const char *bdn
= bdevname(rdev
->bdev
, b
);
2033 clear_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
);
2034 atomic_inc(&rdev
->read_errors
);
2035 if (test_bit(R5_ReadRepl
, &sh
->dev
[i
].flags
))
2038 "md/raid:%s: read error on replacement device "
2039 "(sector %llu on %s).\n",
2040 mdname(conf
->mddev
),
2041 (unsigned long long)s
,
2043 else if (conf
->mddev
->degraded
>= conf
->max_degraded
) {
2047 "md/raid:%s: read error not correctable "
2048 "(sector %llu on %s).\n",
2049 mdname(conf
->mddev
),
2050 (unsigned long long)s
,
2052 } else if (test_bit(R5_ReWrite
, &sh
->dev
[i
].flags
)) {
2057 "md/raid:%s: read error NOT corrected!! "
2058 "(sector %llu on %s).\n",
2059 mdname(conf
->mddev
),
2060 (unsigned long long)s
,
2062 } else if (atomic_read(&rdev
->read_errors
)
2063 > conf
->max_nr_stripes
)
2065 "md/raid:%s: Too many read errors, failing device %s.\n",
2066 mdname(conf
->mddev
), bdn
);
2069 if (set_bad
&& test_bit(In_sync
, &rdev
->flags
)
2070 && !test_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
))
2073 if (test_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
)) {
2074 set_bit(R5_ReadError
, &sh
->dev
[i
].flags
);
2075 clear_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
);
2077 set_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
);
2079 clear_bit(R5_ReadError
, &sh
->dev
[i
].flags
);
2080 clear_bit(R5_ReWrite
, &sh
->dev
[i
].flags
);
2082 && test_bit(In_sync
, &rdev
->flags
)
2083 && rdev_set_badblocks(
2084 rdev
, sh
->sector
, STRIPE_SECTORS
, 0)))
2085 md_error(conf
->mddev
, rdev
);
2088 rdev_dec_pending(rdev
, conf
->mddev
);
2089 clear_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
2090 set_bit(STRIPE_HANDLE
, &sh
->state
);
2094 static void raid5_end_write_request(struct bio
*bi
, int error
)
2096 struct stripe_head
*sh
= bi
->bi_private
;
2097 struct r5conf
*conf
= sh
->raid_conf
;
2098 int disks
= sh
->disks
, i
;
2099 struct md_rdev
*uninitialized_var(rdev
);
2100 int uptodate
= test_bit(BIO_UPTODATE
, &bi
->bi_flags
);
2103 int replacement
= 0;
2105 for (i
= 0 ; i
< disks
; i
++) {
2106 if (bi
== &sh
->dev
[i
].req
) {
2107 rdev
= conf
->disks
[i
].rdev
;
2110 if (bi
== &sh
->dev
[i
].rreq
) {
2111 rdev
= conf
->disks
[i
].replacement
;
2115 /* rdev was removed and 'replacement'
2116 * replaced it. rdev is not removed
2117 * until all requests are finished.
2119 rdev
= conf
->disks
[i
].rdev
;
2123 pr_debug("end_write_request %llu/%d, count %d, uptodate: %d.\n",
2124 (unsigned long long)sh
->sector
, i
, atomic_read(&sh
->count
),
2133 md_error(conf
->mddev
, rdev
);
2134 else if (is_badblock(rdev
, sh
->sector
,
2136 &first_bad
, &bad_sectors
))
2137 set_bit(R5_MadeGoodRepl
, &sh
->dev
[i
].flags
);
2140 set_bit(STRIPE_DEGRADED
, &sh
->state
);
2141 set_bit(WriteErrorSeen
, &rdev
->flags
);
2142 set_bit(R5_WriteError
, &sh
->dev
[i
].flags
);
2143 if (!test_and_set_bit(WantReplacement
, &rdev
->flags
))
2144 set_bit(MD_RECOVERY_NEEDED
,
2145 &rdev
->mddev
->recovery
);
2146 } else if (is_badblock(rdev
, sh
->sector
,
2148 &first_bad
, &bad_sectors
)) {
2149 set_bit(R5_MadeGood
, &sh
->dev
[i
].flags
);
2150 if (test_bit(R5_ReadError
, &sh
->dev
[i
].flags
))
2151 /* That was a successful write so make
2152 * sure it looks like we already did
2155 set_bit(R5_ReWrite
, &sh
->dev
[i
].flags
);
2158 rdev_dec_pending(rdev
, conf
->mddev
);
2160 if (!test_and_clear_bit(R5_DOUBLE_LOCKED
, &sh
->dev
[i
].flags
))
2161 clear_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
2162 set_bit(STRIPE_HANDLE
, &sh
->state
);
2166 static sector_t
compute_blocknr(struct stripe_head
*sh
, int i
, int previous
);
2168 static void raid5_build_block(struct stripe_head
*sh
, int i
, int previous
)
2170 struct r5dev
*dev
= &sh
->dev
[i
];
2172 bio_init(&dev
->req
);
2173 dev
->req
.bi_io_vec
= &dev
->vec
;
2174 dev
->req
.bi_max_vecs
= 1;
2175 dev
->req
.bi_private
= sh
;
2177 bio_init(&dev
->rreq
);
2178 dev
->rreq
.bi_io_vec
= &dev
->rvec
;
2179 dev
->rreq
.bi_max_vecs
= 1;
2180 dev
->rreq
.bi_private
= sh
;
2183 dev
->sector
= compute_blocknr(sh
, i
, previous
);
2186 static void error(struct mddev
*mddev
, struct md_rdev
*rdev
)
2188 char b
[BDEVNAME_SIZE
];
2189 struct r5conf
*conf
= mddev
->private;
2190 unsigned long flags
;
2191 pr_debug("raid456: error called\n");
2193 spin_lock_irqsave(&conf
->device_lock
, flags
);
2194 clear_bit(In_sync
, &rdev
->flags
);
2195 mddev
->degraded
= calc_degraded(conf
);
2196 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
2197 set_bit(MD_RECOVERY_INTR
, &mddev
->recovery
);
2199 set_bit(Blocked
, &rdev
->flags
);
2200 set_bit(Faulty
, &rdev
->flags
);
2201 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
2203 "md/raid:%s: Disk failure on %s, disabling device.\n"
2204 "md/raid:%s: Operation continuing on %d devices.\n",
2206 bdevname(rdev
->bdev
, b
),
2208 conf
->raid_disks
- mddev
->degraded
);
2212 * Input: a 'big' sector number,
2213 * Output: index of the data and parity disk, and the sector # in them.
2215 static sector_t
raid5_compute_sector(struct r5conf
*conf
, sector_t r_sector
,
2216 int previous
, int *dd_idx
,
2217 struct stripe_head
*sh
)
2219 sector_t stripe
, stripe2
;
2220 sector_t chunk_number
;
2221 unsigned int chunk_offset
;
2224 sector_t new_sector
;
2225 int algorithm
= previous
? conf
->prev_algo
2227 int sectors_per_chunk
= previous
? conf
->prev_chunk_sectors
2228 : conf
->chunk_sectors
;
2229 int raid_disks
= previous
? conf
->previous_raid_disks
2231 int data_disks
= raid_disks
- conf
->max_degraded
;
2233 /* First compute the information on this sector */
2236 * Compute the chunk number and the sector offset inside the chunk
2238 chunk_offset
= sector_div(r_sector
, sectors_per_chunk
);
2239 chunk_number
= r_sector
;
2242 * Compute the stripe number
2244 stripe
= chunk_number
;
2245 *dd_idx
= sector_div(stripe
, data_disks
);
2248 * Select the parity disk based on the user selected algorithm.
2250 pd_idx
= qd_idx
= -1;
2251 switch(conf
->level
) {
2253 pd_idx
= data_disks
;
2256 switch (algorithm
) {
2257 case ALGORITHM_LEFT_ASYMMETRIC
:
2258 pd_idx
= data_disks
- sector_div(stripe2
, raid_disks
);
2259 if (*dd_idx
>= pd_idx
)
2262 case ALGORITHM_RIGHT_ASYMMETRIC
:
2263 pd_idx
= sector_div(stripe2
, raid_disks
);
2264 if (*dd_idx
>= pd_idx
)
2267 case ALGORITHM_LEFT_SYMMETRIC
:
2268 pd_idx
= data_disks
- sector_div(stripe2
, raid_disks
);
2269 *dd_idx
= (pd_idx
+ 1 + *dd_idx
) % raid_disks
;
2271 case ALGORITHM_RIGHT_SYMMETRIC
:
2272 pd_idx
= sector_div(stripe2
, raid_disks
);
2273 *dd_idx
= (pd_idx
+ 1 + *dd_idx
) % raid_disks
;
2275 case ALGORITHM_PARITY_0
:
2279 case ALGORITHM_PARITY_N
:
2280 pd_idx
= data_disks
;
2288 switch (algorithm
) {
2289 case ALGORITHM_LEFT_ASYMMETRIC
:
2290 pd_idx
= raid_disks
- 1 - sector_div(stripe2
, raid_disks
);
2291 qd_idx
= pd_idx
+ 1;
2292 if (pd_idx
== raid_disks
-1) {
2293 (*dd_idx
)++; /* Q D D D P */
2295 } else if (*dd_idx
>= pd_idx
)
2296 (*dd_idx
) += 2; /* D D P Q D */
2298 case ALGORITHM_RIGHT_ASYMMETRIC
:
2299 pd_idx
= sector_div(stripe2
, raid_disks
);
2300 qd_idx
= pd_idx
+ 1;
2301 if (pd_idx
== raid_disks
-1) {
2302 (*dd_idx
)++; /* Q D D D P */
2304 } else if (*dd_idx
>= pd_idx
)
2305 (*dd_idx
) += 2; /* D D P Q D */
2307 case ALGORITHM_LEFT_SYMMETRIC
:
2308 pd_idx
= raid_disks
- 1 - sector_div(stripe2
, raid_disks
);
2309 qd_idx
= (pd_idx
+ 1) % raid_disks
;
2310 *dd_idx
= (pd_idx
+ 2 + *dd_idx
) % raid_disks
;
2312 case ALGORITHM_RIGHT_SYMMETRIC
:
2313 pd_idx
= sector_div(stripe2
, raid_disks
);
2314 qd_idx
= (pd_idx
+ 1) % raid_disks
;
2315 *dd_idx
= (pd_idx
+ 2 + *dd_idx
) % raid_disks
;
2318 case ALGORITHM_PARITY_0
:
2323 case ALGORITHM_PARITY_N
:
2324 pd_idx
= data_disks
;
2325 qd_idx
= data_disks
+ 1;
2328 case ALGORITHM_ROTATING_ZERO_RESTART
:
2329 /* Exactly the same as RIGHT_ASYMMETRIC, but or
2330 * of blocks for computing Q is different.
2332 pd_idx
= sector_div(stripe2
, raid_disks
);
2333 qd_idx
= pd_idx
+ 1;
2334 if (pd_idx
== raid_disks
-1) {
2335 (*dd_idx
)++; /* Q D D D P */
2337 } else if (*dd_idx
>= pd_idx
)
2338 (*dd_idx
) += 2; /* D D P Q D */
2342 case ALGORITHM_ROTATING_N_RESTART
:
2343 /* Same a left_asymmetric, by first stripe is
2344 * D D D P Q rather than
2348 pd_idx
= raid_disks
- 1 - sector_div(stripe2
, raid_disks
);
2349 qd_idx
= pd_idx
+ 1;
2350 if (pd_idx
== raid_disks
-1) {
2351 (*dd_idx
)++; /* Q D D D P */
2353 } else if (*dd_idx
>= pd_idx
)
2354 (*dd_idx
) += 2; /* D D P Q D */
2358 case ALGORITHM_ROTATING_N_CONTINUE
:
2359 /* Same as left_symmetric but Q is before P */
2360 pd_idx
= raid_disks
- 1 - sector_div(stripe2
, raid_disks
);
2361 qd_idx
= (pd_idx
+ raid_disks
- 1) % raid_disks
;
2362 *dd_idx
= (pd_idx
+ 1 + *dd_idx
) % raid_disks
;
2366 case ALGORITHM_LEFT_ASYMMETRIC_6
:
2367 /* RAID5 left_asymmetric, with Q on last device */
2368 pd_idx
= data_disks
- sector_div(stripe2
, raid_disks
-1);
2369 if (*dd_idx
>= pd_idx
)
2371 qd_idx
= raid_disks
- 1;
2374 case ALGORITHM_RIGHT_ASYMMETRIC_6
:
2375 pd_idx
= sector_div(stripe2
, raid_disks
-1);
2376 if (*dd_idx
>= pd_idx
)
2378 qd_idx
= raid_disks
- 1;
2381 case ALGORITHM_LEFT_SYMMETRIC_6
:
2382 pd_idx
= data_disks
- sector_div(stripe2
, raid_disks
-1);
2383 *dd_idx
= (pd_idx
+ 1 + *dd_idx
) % (raid_disks
-1);
2384 qd_idx
= raid_disks
- 1;
2387 case ALGORITHM_RIGHT_SYMMETRIC_6
:
2388 pd_idx
= sector_div(stripe2
, raid_disks
-1);
2389 *dd_idx
= (pd_idx
+ 1 + *dd_idx
) % (raid_disks
-1);
2390 qd_idx
= raid_disks
- 1;
2393 case ALGORITHM_PARITY_0_6
:
2396 qd_idx
= raid_disks
- 1;
2406 sh
->pd_idx
= pd_idx
;
2407 sh
->qd_idx
= qd_idx
;
2408 sh
->ddf_layout
= ddf_layout
;
2411 * Finally, compute the new sector number
2413 new_sector
= (sector_t
)stripe
* sectors_per_chunk
+ chunk_offset
;
2417 static sector_t
compute_blocknr(struct stripe_head
*sh
, int i
, int previous
)
2419 struct r5conf
*conf
= sh
->raid_conf
;
2420 int raid_disks
= sh
->disks
;
2421 int data_disks
= raid_disks
- conf
->max_degraded
;
2422 sector_t new_sector
= sh
->sector
, check
;
2423 int sectors_per_chunk
= previous
? conf
->prev_chunk_sectors
2424 : conf
->chunk_sectors
;
2425 int algorithm
= previous
? conf
->prev_algo
2429 sector_t chunk_number
;
2430 int dummy1
, dd_idx
= i
;
2432 struct stripe_head sh2
;
2434 chunk_offset
= sector_div(new_sector
, sectors_per_chunk
);
2435 stripe
= new_sector
;
2437 if (i
== sh
->pd_idx
)
2439 switch(conf
->level
) {
2442 switch (algorithm
) {
2443 case ALGORITHM_LEFT_ASYMMETRIC
:
2444 case ALGORITHM_RIGHT_ASYMMETRIC
:
2448 case ALGORITHM_LEFT_SYMMETRIC
:
2449 case ALGORITHM_RIGHT_SYMMETRIC
:
2452 i
-= (sh
->pd_idx
+ 1);
2454 case ALGORITHM_PARITY_0
:
2457 case ALGORITHM_PARITY_N
:
2464 if (i
== sh
->qd_idx
)
2465 return 0; /* It is the Q disk */
2466 switch (algorithm
) {
2467 case ALGORITHM_LEFT_ASYMMETRIC
:
2468 case ALGORITHM_RIGHT_ASYMMETRIC
:
2469 case ALGORITHM_ROTATING_ZERO_RESTART
:
2470 case ALGORITHM_ROTATING_N_RESTART
:
2471 if (sh
->pd_idx
== raid_disks
-1)
2472 i
--; /* Q D D D P */
2473 else if (i
> sh
->pd_idx
)
2474 i
-= 2; /* D D P Q D */
2476 case ALGORITHM_LEFT_SYMMETRIC
:
2477 case ALGORITHM_RIGHT_SYMMETRIC
:
2478 if (sh
->pd_idx
== raid_disks
-1)
2479 i
--; /* Q D D D P */
2484 i
-= (sh
->pd_idx
+ 2);
2487 case ALGORITHM_PARITY_0
:
2490 case ALGORITHM_PARITY_N
:
2492 case ALGORITHM_ROTATING_N_CONTINUE
:
2493 /* Like left_symmetric, but P is before Q */
2494 if (sh
->pd_idx
== 0)
2495 i
--; /* P D D D Q */
2500 i
-= (sh
->pd_idx
+ 1);
2503 case ALGORITHM_LEFT_ASYMMETRIC_6
:
2504 case ALGORITHM_RIGHT_ASYMMETRIC_6
:
2508 case ALGORITHM_LEFT_SYMMETRIC_6
:
2509 case ALGORITHM_RIGHT_SYMMETRIC_6
:
2511 i
+= data_disks
+ 1;
2512 i
-= (sh
->pd_idx
+ 1);
2514 case ALGORITHM_PARITY_0_6
:
2523 chunk_number
= stripe
* data_disks
+ i
;
2524 r_sector
= chunk_number
* sectors_per_chunk
+ chunk_offset
;
2526 check
= raid5_compute_sector(conf
, r_sector
,
2527 previous
, &dummy1
, &sh2
);
2528 if (check
!= sh
->sector
|| dummy1
!= dd_idx
|| sh2
.pd_idx
!= sh
->pd_idx
2529 || sh2
.qd_idx
!= sh
->qd_idx
) {
2530 printk(KERN_ERR
"md/raid:%s: compute_blocknr: map not correct\n",
2531 mdname(conf
->mddev
));
2538 schedule_reconstruction(struct stripe_head
*sh
, struct stripe_head_state
*s
,
2539 int rcw
, int expand
)
2541 int i
, pd_idx
= sh
->pd_idx
, disks
= sh
->disks
;
2542 struct r5conf
*conf
= sh
->raid_conf
;
2543 int level
= conf
->level
;
2547 for (i
= disks
; i
--; ) {
2548 struct r5dev
*dev
= &sh
->dev
[i
];
2551 set_bit(R5_LOCKED
, &dev
->flags
);
2552 set_bit(R5_Wantdrain
, &dev
->flags
);
2554 clear_bit(R5_UPTODATE
, &dev
->flags
);
2558 /* if we are not expanding this is a proper write request, and
2559 * there will be bios with new data to be drained into the
2564 /* False alarm, nothing to do */
2566 sh
->reconstruct_state
= reconstruct_state_drain_run
;
2567 set_bit(STRIPE_OP_BIODRAIN
, &s
->ops_request
);
2569 sh
->reconstruct_state
= reconstruct_state_run
;
2571 set_bit(STRIPE_OP_RECONSTRUCT
, &s
->ops_request
);
2573 if (s
->locked
+ conf
->max_degraded
== disks
)
2574 if (!test_and_set_bit(STRIPE_FULL_WRITE
, &sh
->state
))
2575 atomic_inc(&conf
->pending_full_writes
);
2578 BUG_ON(!(test_bit(R5_UPTODATE
, &sh
->dev
[pd_idx
].flags
) ||
2579 test_bit(R5_Wantcompute
, &sh
->dev
[pd_idx
].flags
)));
2581 for (i
= disks
; i
--; ) {
2582 struct r5dev
*dev
= &sh
->dev
[i
];
2587 (test_bit(R5_UPTODATE
, &dev
->flags
) ||
2588 test_bit(R5_Wantcompute
, &dev
->flags
))) {
2589 set_bit(R5_Wantdrain
, &dev
->flags
);
2590 set_bit(R5_LOCKED
, &dev
->flags
);
2591 clear_bit(R5_UPTODATE
, &dev
->flags
);
2596 /* False alarm - nothing to do */
2598 sh
->reconstruct_state
= reconstruct_state_prexor_drain_run
;
2599 set_bit(STRIPE_OP_PREXOR
, &s
->ops_request
);
2600 set_bit(STRIPE_OP_BIODRAIN
, &s
->ops_request
);
2601 set_bit(STRIPE_OP_RECONSTRUCT
, &s
->ops_request
);
2604 /* keep the parity disk(s) locked while asynchronous operations
2607 set_bit(R5_LOCKED
, &sh
->dev
[pd_idx
].flags
);
2608 clear_bit(R5_UPTODATE
, &sh
->dev
[pd_idx
].flags
);
2612 int qd_idx
= sh
->qd_idx
;
2613 struct r5dev
*dev
= &sh
->dev
[qd_idx
];
2615 set_bit(R5_LOCKED
, &dev
->flags
);
2616 clear_bit(R5_UPTODATE
, &dev
->flags
);
2620 pr_debug("%s: stripe %llu locked: %d ops_request: %lx\n",
2621 __func__
, (unsigned long long)sh
->sector
,
2622 s
->locked
, s
->ops_request
);
2626 * Each stripe/dev can have one or more bion attached.
2627 * toread/towrite point to the first in a chain.
2628 * The bi_next chain must be in order.
2630 static int add_stripe_bio(struct stripe_head
*sh
, struct bio
*bi
, int dd_idx
, int forwrite
)
2633 struct r5conf
*conf
= sh
->raid_conf
;
2636 pr_debug("adding bi b#%llu to stripe s#%llu\n",
2637 (unsigned long long)bi
->bi_iter
.bi_sector
,
2638 (unsigned long long)sh
->sector
);
2641 * If several bio share a stripe. The bio bi_phys_segments acts as a
2642 * reference count to avoid race. The reference count should already be
2643 * increased before this function is called (for example, in
2644 * make_request()), so other bio sharing this stripe will not free the
2645 * stripe. If a stripe is owned by one stripe, the stripe lock will
2648 spin_lock_irq(&sh
->stripe_lock
);
2650 bip
= &sh
->dev
[dd_idx
].towrite
;
2654 bip
= &sh
->dev
[dd_idx
].toread
;
2655 while (*bip
&& (*bip
)->bi_iter
.bi_sector
< bi
->bi_iter
.bi_sector
) {
2656 if (bio_end_sector(*bip
) > bi
->bi_iter
.bi_sector
)
2658 bip
= & (*bip
)->bi_next
;
2660 if (*bip
&& (*bip
)->bi_iter
.bi_sector
< bio_end_sector(bi
))
2663 BUG_ON(*bip
&& bi
->bi_next
&& (*bip
) != bi
->bi_next
);
2667 raid5_inc_bi_active_stripes(bi
);
2670 /* check if page is covered */
2671 sector_t sector
= sh
->dev
[dd_idx
].sector
;
2672 for (bi
=sh
->dev
[dd_idx
].towrite
;
2673 sector
< sh
->dev
[dd_idx
].sector
+ STRIPE_SECTORS
&&
2674 bi
&& bi
->bi_iter
.bi_sector
<= sector
;
2675 bi
= r5_next_bio(bi
, sh
->dev
[dd_idx
].sector
)) {
2676 if (bio_end_sector(bi
) >= sector
)
2677 sector
= bio_end_sector(bi
);
2679 if (sector
>= sh
->dev
[dd_idx
].sector
+ STRIPE_SECTORS
)
2680 set_bit(R5_OVERWRITE
, &sh
->dev
[dd_idx
].flags
);
2683 pr_debug("added bi b#%llu to stripe s#%llu, disk %d.\n",
2684 (unsigned long long)(*bip
)->bi_iter
.bi_sector
,
2685 (unsigned long long)sh
->sector
, dd_idx
);
2686 spin_unlock_irq(&sh
->stripe_lock
);
2688 if (conf
->mddev
->bitmap
&& firstwrite
) {
2689 bitmap_startwrite(conf
->mddev
->bitmap
, sh
->sector
,
2691 sh
->bm_seq
= conf
->seq_flush
+1;
2692 set_bit(STRIPE_BIT_DELAY
, &sh
->state
);
2697 set_bit(R5_Overlap
, &sh
->dev
[dd_idx
].flags
);
2698 spin_unlock_irq(&sh
->stripe_lock
);
2702 static void end_reshape(struct r5conf
*conf
);
2704 static void stripe_set_idx(sector_t stripe
, struct r5conf
*conf
, int previous
,
2705 struct stripe_head
*sh
)
2707 int sectors_per_chunk
=
2708 previous
? conf
->prev_chunk_sectors
: conf
->chunk_sectors
;
2710 int chunk_offset
= sector_div(stripe
, sectors_per_chunk
);
2711 int disks
= previous
? conf
->previous_raid_disks
: conf
->raid_disks
;
2713 raid5_compute_sector(conf
,
2714 stripe
* (disks
- conf
->max_degraded
)
2715 *sectors_per_chunk
+ chunk_offset
,
2721 handle_failed_stripe(struct r5conf
*conf
, struct stripe_head
*sh
,
2722 struct stripe_head_state
*s
, int disks
,
2723 struct bio
**return_bi
)
2726 for (i
= disks
; i
--; ) {
2730 if (test_bit(R5_ReadError
, &sh
->dev
[i
].flags
)) {
2731 struct md_rdev
*rdev
;
2733 rdev
= rcu_dereference(conf
->disks
[i
].rdev
);
2734 if (rdev
&& test_bit(In_sync
, &rdev
->flags
))
2735 atomic_inc(&rdev
->nr_pending
);
2740 if (!rdev_set_badblocks(
2744 md_error(conf
->mddev
, rdev
);
2745 rdev_dec_pending(rdev
, conf
->mddev
);
2748 spin_lock_irq(&sh
->stripe_lock
);
2749 /* fail all writes first */
2750 bi
= sh
->dev
[i
].towrite
;
2751 sh
->dev
[i
].towrite
= NULL
;
2752 spin_unlock_irq(&sh
->stripe_lock
);
2756 if (test_and_clear_bit(R5_Overlap
, &sh
->dev
[i
].flags
))
2757 wake_up(&conf
->wait_for_overlap
);
2759 while (bi
&& bi
->bi_iter
.bi_sector
<
2760 sh
->dev
[i
].sector
+ STRIPE_SECTORS
) {
2761 struct bio
*nextbi
= r5_next_bio(bi
, sh
->dev
[i
].sector
);
2762 clear_bit(BIO_UPTODATE
, &bi
->bi_flags
);
2763 if (!raid5_dec_bi_active_stripes(bi
)) {
2764 md_write_end(conf
->mddev
);
2765 bi
->bi_next
= *return_bi
;
2771 bitmap_endwrite(conf
->mddev
->bitmap
, sh
->sector
,
2772 STRIPE_SECTORS
, 0, 0);
2774 /* and fail all 'written' */
2775 bi
= sh
->dev
[i
].written
;
2776 sh
->dev
[i
].written
= NULL
;
2777 if (test_and_clear_bit(R5_SkipCopy
, &sh
->dev
[i
].flags
)) {
2778 WARN_ON(test_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
));
2779 sh
->dev
[i
].page
= sh
->dev
[i
].orig_page
;
2782 if (bi
) bitmap_end
= 1;
2783 while (bi
&& bi
->bi_iter
.bi_sector
<
2784 sh
->dev
[i
].sector
+ STRIPE_SECTORS
) {
2785 struct bio
*bi2
= r5_next_bio(bi
, sh
->dev
[i
].sector
);
2786 clear_bit(BIO_UPTODATE
, &bi
->bi_flags
);
2787 if (!raid5_dec_bi_active_stripes(bi
)) {
2788 md_write_end(conf
->mddev
);
2789 bi
->bi_next
= *return_bi
;
2795 /* fail any reads if this device is non-operational and
2796 * the data has not reached the cache yet.
2798 if (!test_bit(R5_Wantfill
, &sh
->dev
[i
].flags
) &&
2799 (!test_bit(R5_Insync
, &sh
->dev
[i
].flags
) ||
2800 test_bit(R5_ReadError
, &sh
->dev
[i
].flags
))) {
2801 spin_lock_irq(&sh
->stripe_lock
);
2802 bi
= sh
->dev
[i
].toread
;
2803 sh
->dev
[i
].toread
= NULL
;
2804 spin_unlock_irq(&sh
->stripe_lock
);
2805 if (test_and_clear_bit(R5_Overlap
, &sh
->dev
[i
].flags
))
2806 wake_up(&conf
->wait_for_overlap
);
2807 while (bi
&& bi
->bi_iter
.bi_sector
<
2808 sh
->dev
[i
].sector
+ STRIPE_SECTORS
) {
2809 struct bio
*nextbi
=
2810 r5_next_bio(bi
, sh
->dev
[i
].sector
);
2811 clear_bit(BIO_UPTODATE
, &bi
->bi_flags
);
2812 if (!raid5_dec_bi_active_stripes(bi
)) {
2813 bi
->bi_next
= *return_bi
;
2820 bitmap_endwrite(conf
->mddev
->bitmap
, sh
->sector
,
2821 STRIPE_SECTORS
, 0, 0);
2822 /* If we were in the middle of a write the parity block might
2823 * still be locked - so just clear all R5_LOCKED flags
2825 clear_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
2828 if (test_and_clear_bit(STRIPE_FULL_WRITE
, &sh
->state
))
2829 if (atomic_dec_and_test(&conf
->pending_full_writes
))
2830 md_wakeup_thread(conf
->mddev
->thread
);
2834 handle_failed_sync(struct r5conf
*conf
, struct stripe_head
*sh
,
2835 struct stripe_head_state
*s
)
2840 clear_bit(STRIPE_SYNCING
, &sh
->state
);
2841 if (test_and_clear_bit(R5_Overlap
, &sh
->dev
[sh
->pd_idx
].flags
))
2842 wake_up(&conf
->wait_for_overlap
);
2845 /* There is nothing more to do for sync/check/repair.
2846 * Don't even need to abort as that is handled elsewhere
2847 * if needed, and not always wanted e.g. if there is a known
2849 * For recover/replace we need to record a bad block on all
2850 * non-sync devices, or abort the recovery
2852 if (test_bit(MD_RECOVERY_RECOVER
, &conf
->mddev
->recovery
)) {
2853 /* During recovery devices cannot be removed, so
2854 * locking and refcounting of rdevs is not needed
2856 for (i
= 0; i
< conf
->raid_disks
; i
++) {
2857 struct md_rdev
*rdev
= conf
->disks
[i
].rdev
;
2859 && !test_bit(Faulty
, &rdev
->flags
)
2860 && !test_bit(In_sync
, &rdev
->flags
)
2861 && !rdev_set_badblocks(rdev
, sh
->sector
,
2864 rdev
= conf
->disks
[i
].replacement
;
2866 && !test_bit(Faulty
, &rdev
->flags
)
2867 && !test_bit(In_sync
, &rdev
->flags
)
2868 && !rdev_set_badblocks(rdev
, sh
->sector
,
2873 conf
->recovery_disabled
=
2874 conf
->mddev
->recovery_disabled
;
2876 md_done_sync(conf
->mddev
, STRIPE_SECTORS
, !abort
);
2879 static int want_replace(struct stripe_head
*sh
, int disk_idx
)
2881 struct md_rdev
*rdev
;
2883 /* Doing recovery so rcu locking not required */
2884 rdev
= sh
->raid_conf
->disks
[disk_idx
].replacement
;
2886 && !test_bit(Faulty
, &rdev
->flags
)
2887 && !test_bit(In_sync
, &rdev
->flags
)
2888 && (rdev
->recovery_offset
<= sh
->sector
2889 || rdev
->mddev
->recovery_cp
<= sh
->sector
))
2895 /* fetch_block - checks the given member device to see if its data needs
2896 * to be read or computed to satisfy a request.
2898 * Returns 1 when no more member devices need to be checked, otherwise returns
2899 * 0 to tell the loop in handle_stripe_fill to continue
2901 static int fetch_block(struct stripe_head
*sh
, struct stripe_head_state
*s
,
2902 int disk_idx
, int disks
)
2904 struct r5dev
*dev
= &sh
->dev
[disk_idx
];
2905 struct r5dev
*fdev
[2] = { &sh
->dev
[s
->failed_num
[0]],
2906 &sh
->dev
[s
->failed_num
[1]] };
2908 /* is the data in this block needed, and can we get it? */
2909 if (!test_bit(R5_LOCKED
, &dev
->flags
) &&
2910 !test_bit(R5_UPTODATE
, &dev
->flags
) &&
2912 (dev
->towrite
&& !test_bit(R5_OVERWRITE
, &dev
->flags
)) ||
2913 s
->syncing
|| s
->expanding
||
2914 (s
->replacing
&& want_replace(sh
, disk_idx
)) ||
2915 (s
->failed
>= 1 && fdev
[0]->toread
) ||
2916 (s
->failed
>= 2 && fdev
[1]->toread
) ||
2917 (sh
->raid_conf
->level
<= 5 && s
->failed
&& fdev
[0]->towrite
&&
2918 (!test_bit(R5_Insync
, &dev
->flags
) || test_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
)) &&
2919 !test_bit(R5_OVERWRITE
, &fdev
[0]->flags
)) ||
2920 ((sh
->raid_conf
->level
== 6 ||
2921 sh
->sector
>= sh
->raid_conf
->mddev
->recovery_cp
)
2922 && s
->failed
&& s
->to_write
&&
2923 (s
->to_write
- s
->non_overwrite
<
2924 sh
->raid_conf
->raid_disks
- sh
->raid_conf
->max_degraded
) &&
2925 (!test_bit(R5_Insync
, &dev
->flags
) || test_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))))) {
2926 /* we would like to get this block, possibly by computing it,
2927 * otherwise read it if the backing disk is insync
2929 BUG_ON(test_bit(R5_Wantcompute
, &dev
->flags
));
2930 BUG_ON(test_bit(R5_Wantread
, &dev
->flags
));
2931 if ((s
->uptodate
== disks
- 1) &&
2932 (s
->failed
&& (disk_idx
== s
->failed_num
[0] ||
2933 disk_idx
== s
->failed_num
[1]))) {
2934 /* have disk failed, and we're requested to fetch it;
2937 pr_debug("Computing stripe %llu block %d\n",
2938 (unsigned long long)sh
->sector
, disk_idx
);
2939 set_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
2940 set_bit(STRIPE_OP_COMPUTE_BLK
, &s
->ops_request
);
2941 set_bit(R5_Wantcompute
, &dev
->flags
);
2942 sh
->ops
.target
= disk_idx
;
2943 sh
->ops
.target2
= -1; /* no 2nd target */
2945 /* Careful: from this point on 'uptodate' is in the eye
2946 * of raid_run_ops which services 'compute' operations
2947 * before writes. R5_Wantcompute flags a block that will
2948 * be R5_UPTODATE by the time it is needed for a
2949 * subsequent operation.
2953 } else if (s
->uptodate
== disks
-2 && s
->failed
>= 2) {
2954 /* Computing 2-failure is *very* expensive; only
2955 * do it if failed >= 2
2958 for (other
= disks
; other
--; ) {
2959 if (other
== disk_idx
)
2961 if (!test_bit(R5_UPTODATE
,
2962 &sh
->dev
[other
].flags
))
2966 pr_debug("Computing stripe %llu blocks %d,%d\n",
2967 (unsigned long long)sh
->sector
,
2969 set_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
2970 set_bit(STRIPE_OP_COMPUTE_BLK
, &s
->ops_request
);
2971 set_bit(R5_Wantcompute
, &sh
->dev
[disk_idx
].flags
);
2972 set_bit(R5_Wantcompute
, &sh
->dev
[other
].flags
);
2973 sh
->ops
.target
= disk_idx
;
2974 sh
->ops
.target2
= other
;
2978 } else if (test_bit(R5_Insync
, &dev
->flags
)) {
2979 set_bit(R5_LOCKED
, &dev
->flags
);
2980 set_bit(R5_Wantread
, &dev
->flags
);
2982 pr_debug("Reading block %d (sync=%d)\n",
2983 disk_idx
, s
->syncing
);
2991 * handle_stripe_fill - read or compute data to satisfy pending requests.
2993 static void handle_stripe_fill(struct stripe_head
*sh
,
2994 struct stripe_head_state
*s
,
2999 /* look for blocks to read/compute, skip this if a compute
3000 * is already in flight, or if the stripe contents are in the
3001 * midst of changing due to a write
3003 if (!test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
) && !sh
->check_state
&&
3004 !sh
->reconstruct_state
)
3005 for (i
= disks
; i
--; )
3006 if (fetch_block(sh
, s
, i
, disks
))
3008 set_bit(STRIPE_HANDLE
, &sh
->state
);
3011 /* handle_stripe_clean_event
3012 * any written block on an uptodate or failed drive can be returned.
3013 * Note that if we 'wrote' to a failed drive, it will be UPTODATE, but
3014 * never LOCKED, so we don't need to test 'failed' directly.
3016 static void handle_stripe_clean_event(struct r5conf
*conf
,
3017 struct stripe_head
*sh
, int disks
, struct bio
**return_bi
)
3021 int discard_pending
= 0;
3023 for (i
= disks
; i
--; )
3024 if (sh
->dev
[i
].written
) {
3026 if (!test_bit(R5_LOCKED
, &dev
->flags
) &&
3027 (test_bit(R5_UPTODATE
, &dev
->flags
) ||
3028 test_bit(R5_Discard
, &dev
->flags
) ||
3029 test_bit(R5_SkipCopy
, &dev
->flags
))) {
3030 /* We can return any write requests */
3031 struct bio
*wbi
, *wbi2
;
3032 pr_debug("Return write for disc %d\n", i
);
3033 if (test_and_clear_bit(R5_Discard
, &dev
->flags
))
3034 clear_bit(R5_UPTODATE
, &dev
->flags
);
3035 if (test_and_clear_bit(R5_SkipCopy
, &dev
->flags
)) {
3036 WARN_ON(test_bit(R5_UPTODATE
, &dev
->flags
));
3037 dev
->page
= dev
->orig_page
;
3040 dev
->written
= NULL
;
3041 while (wbi
&& wbi
->bi_iter
.bi_sector
<
3042 dev
->sector
+ STRIPE_SECTORS
) {
3043 wbi2
= r5_next_bio(wbi
, dev
->sector
);
3044 if (!raid5_dec_bi_active_stripes(wbi
)) {
3045 md_write_end(conf
->mddev
);
3046 wbi
->bi_next
= *return_bi
;
3051 bitmap_endwrite(conf
->mddev
->bitmap
, sh
->sector
,
3053 !test_bit(STRIPE_DEGRADED
, &sh
->state
),
3055 } else if (test_bit(R5_Discard
, &dev
->flags
))
3056 discard_pending
= 1;
3057 WARN_ON(test_bit(R5_SkipCopy
, &dev
->flags
));
3058 WARN_ON(dev
->page
!= dev
->orig_page
);
3060 if (!discard_pending
&&
3061 test_bit(R5_Discard
, &sh
->dev
[sh
->pd_idx
].flags
)) {
3062 clear_bit(R5_Discard
, &sh
->dev
[sh
->pd_idx
].flags
);
3063 clear_bit(R5_UPTODATE
, &sh
->dev
[sh
->pd_idx
].flags
);
3064 if (sh
->qd_idx
>= 0) {
3065 clear_bit(R5_Discard
, &sh
->dev
[sh
->qd_idx
].flags
);
3066 clear_bit(R5_UPTODATE
, &sh
->dev
[sh
->qd_idx
].flags
);
3068 /* now that discard is done we can proceed with any sync */
3069 clear_bit(STRIPE_DISCARD
, &sh
->state
);
3071 * SCSI discard will change some bio fields and the stripe has
3072 * no updated data, so remove it from hash list and the stripe
3073 * will be reinitialized
3075 spin_lock_irq(&conf
->device_lock
);
3077 spin_unlock_irq(&conf
->device_lock
);
3078 if (test_bit(STRIPE_SYNC_REQUESTED
, &sh
->state
))
3079 set_bit(STRIPE_HANDLE
, &sh
->state
);
3083 if (test_and_clear_bit(STRIPE_FULL_WRITE
, &sh
->state
))
3084 if (atomic_dec_and_test(&conf
->pending_full_writes
))
3085 md_wakeup_thread(conf
->mddev
->thread
);
3088 static void handle_stripe_dirtying(struct r5conf
*conf
,
3089 struct stripe_head
*sh
,
3090 struct stripe_head_state
*s
,
3093 int rmw
= 0, rcw
= 0, i
;
3094 sector_t recovery_cp
= conf
->mddev
->recovery_cp
;
3096 /* RAID6 requires 'rcw' in current implementation.
3097 * Otherwise, check whether resync is now happening or should start.
3098 * If yes, then the array is dirty (after unclean shutdown or
3099 * initial creation), so parity in some stripes might be inconsistent.
3100 * In this case, we need to always do reconstruct-write, to ensure
3101 * that in case of drive failure or read-error correction, we
3102 * generate correct data from the parity.
3104 if (conf
->max_degraded
== 2 ||
3105 (recovery_cp
< MaxSector
&& sh
->sector
>= recovery_cp
)) {
3106 /* Calculate the real rcw later - for now make it
3107 * look like rcw is cheaper
3110 pr_debug("force RCW max_degraded=%u, recovery_cp=%llu sh->sector=%llu\n",
3111 conf
->max_degraded
, (unsigned long long)recovery_cp
,
3112 (unsigned long long)sh
->sector
);
3113 } else for (i
= disks
; i
--; ) {
3114 /* would I have to read this buffer for read_modify_write */
3115 struct r5dev
*dev
= &sh
->dev
[i
];
3116 if ((dev
->towrite
|| i
== sh
->pd_idx
) &&
3117 !test_bit(R5_LOCKED
, &dev
->flags
) &&
3118 !(test_bit(R5_UPTODATE
, &dev
->flags
) ||
3119 test_bit(R5_Wantcompute
, &dev
->flags
))) {
3120 if (test_bit(R5_Insync
, &dev
->flags
))
3123 rmw
+= 2*disks
; /* cannot read it */
3125 /* Would I have to read this buffer for reconstruct_write */
3126 if (!test_bit(R5_OVERWRITE
, &dev
->flags
) && i
!= sh
->pd_idx
&&
3127 !test_bit(R5_LOCKED
, &dev
->flags
) &&
3128 !(test_bit(R5_UPTODATE
, &dev
->flags
) ||
3129 test_bit(R5_Wantcompute
, &dev
->flags
))) {
3130 if (test_bit(R5_Insync
, &dev
->flags
))
3136 pr_debug("for sector %llu, rmw=%d rcw=%d\n",
3137 (unsigned long long)sh
->sector
, rmw
, rcw
);
3138 set_bit(STRIPE_HANDLE
, &sh
->state
);
3139 if (rmw
< rcw
&& rmw
> 0) {
3140 /* prefer read-modify-write, but need to get some data */
3141 if (conf
->mddev
->queue
)
3142 blk_add_trace_msg(conf
->mddev
->queue
,
3143 "raid5 rmw %llu %d",
3144 (unsigned long long)sh
->sector
, rmw
);
3145 for (i
= disks
; i
--; ) {
3146 struct r5dev
*dev
= &sh
->dev
[i
];
3147 if ((dev
->towrite
|| i
== sh
->pd_idx
) &&
3148 !test_bit(R5_LOCKED
, &dev
->flags
) &&
3149 !(test_bit(R5_UPTODATE
, &dev
->flags
) ||
3150 test_bit(R5_Wantcompute
, &dev
->flags
)) &&
3151 test_bit(R5_Insync
, &dev
->flags
)) {
3152 if (test_bit(STRIPE_PREREAD_ACTIVE
,
3154 pr_debug("Read_old block %d for r-m-w\n",
3156 set_bit(R5_LOCKED
, &dev
->flags
);
3157 set_bit(R5_Wantread
, &dev
->flags
);
3160 set_bit(STRIPE_DELAYED
, &sh
->state
);
3161 set_bit(STRIPE_HANDLE
, &sh
->state
);
3166 if (rcw
<= rmw
&& rcw
> 0) {
3167 /* want reconstruct write, but need to get some data */
3170 for (i
= disks
; i
--; ) {
3171 struct r5dev
*dev
= &sh
->dev
[i
];
3172 if (!test_bit(R5_OVERWRITE
, &dev
->flags
) &&
3173 i
!= sh
->pd_idx
&& i
!= sh
->qd_idx
&&
3174 !test_bit(R5_LOCKED
, &dev
->flags
) &&
3175 !(test_bit(R5_UPTODATE
, &dev
->flags
) ||
3176 test_bit(R5_Wantcompute
, &dev
->flags
))) {
3178 if (test_bit(R5_Insync
, &dev
->flags
) &&
3179 test_bit(STRIPE_PREREAD_ACTIVE
,
3181 pr_debug("Read_old block "
3182 "%d for Reconstruct\n", i
);
3183 set_bit(R5_LOCKED
, &dev
->flags
);
3184 set_bit(R5_Wantread
, &dev
->flags
);
3188 set_bit(STRIPE_DELAYED
, &sh
->state
);
3189 set_bit(STRIPE_HANDLE
, &sh
->state
);
3193 if (rcw
&& conf
->mddev
->queue
)
3194 blk_add_trace_msg(conf
->mddev
->queue
, "raid5 rcw %llu %d %d %d",
3195 (unsigned long long)sh
->sector
,
3196 rcw
, qread
, test_bit(STRIPE_DELAYED
, &sh
->state
));
3198 /* now if nothing is locked, and if we have enough data,
3199 * we can start a write request
3201 /* since handle_stripe can be called at any time we need to handle the
3202 * case where a compute block operation has been submitted and then a
3203 * subsequent call wants to start a write request. raid_run_ops only
3204 * handles the case where compute block and reconstruct are requested
3205 * simultaneously. If this is not the case then new writes need to be
3206 * held off until the compute completes.
3208 if ((s
->req_compute
|| !test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
)) &&
3209 (s
->locked
== 0 && (rcw
== 0 || rmw
== 0) &&
3210 !test_bit(STRIPE_BIT_DELAY
, &sh
->state
)))
3211 schedule_reconstruction(sh
, s
, rcw
== 0, 0);
3214 static void handle_parity_checks5(struct r5conf
*conf
, struct stripe_head
*sh
,
3215 struct stripe_head_state
*s
, int disks
)
3217 struct r5dev
*dev
= NULL
;
3219 set_bit(STRIPE_HANDLE
, &sh
->state
);
3221 switch (sh
->check_state
) {
3222 case check_state_idle
:
3223 /* start a new check operation if there are no failures */
3224 if (s
->failed
== 0) {
3225 BUG_ON(s
->uptodate
!= disks
);
3226 sh
->check_state
= check_state_run
;
3227 set_bit(STRIPE_OP_CHECK
, &s
->ops_request
);
3228 clear_bit(R5_UPTODATE
, &sh
->dev
[sh
->pd_idx
].flags
);
3232 dev
= &sh
->dev
[s
->failed_num
[0]];
3234 case check_state_compute_result
:
3235 sh
->check_state
= check_state_idle
;
3237 dev
= &sh
->dev
[sh
->pd_idx
];
3239 /* check that a write has not made the stripe insync */
3240 if (test_bit(STRIPE_INSYNC
, &sh
->state
))
3243 /* either failed parity check, or recovery is happening */
3244 BUG_ON(!test_bit(R5_UPTODATE
, &dev
->flags
));
3245 BUG_ON(s
->uptodate
!= disks
);
3247 set_bit(R5_LOCKED
, &dev
->flags
);
3249 set_bit(R5_Wantwrite
, &dev
->flags
);
3251 clear_bit(STRIPE_DEGRADED
, &sh
->state
);
3252 set_bit(STRIPE_INSYNC
, &sh
->state
);
3254 case check_state_run
:
3255 break; /* we will be called again upon completion */
3256 case check_state_check_result
:
3257 sh
->check_state
= check_state_idle
;
3259 /* if a failure occurred during the check operation, leave
3260 * STRIPE_INSYNC not set and let the stripe be handled again
3265 /* handle a successful check operation, if parity is correct
3266 * we are done. Otherwise update the mismatch count and repair
3267 * parity if !MD_RECOVERY_CHECK
3269 if ((sh
->ops
.zero_sum_result
& SUM_CHECK_P_RESULT
) == 0)
3270 /* parity is correct (on disc,
3271 * not in buffer any more)
3273 set_bit(STRIPE_INSYNC
, &sh
->state
);
3275 atomic64_add(STRIPE_SECTORS
, &conf
->mddev
->resync_mismatches
);
3276 if (test_bit(MD_RECOVERY_CHECK
, &conf
->mddev
->recovery
))
3277 /* don't try to repair!! */
3278 set_bit(STRIPE_INSYNC
, &sh
->state
);
3280 sh
->check_state
= check_state_compute_run
;
3281 set_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
3282 set_bit(STRIPE_OP_COMPUTE_BLK
, &s
->ops_request
);
3283 set_bit(R5_Wantcompute
,
3284 &sh
->dev
[sh
->pd_idx
].flags
);
3285 sh
->ops
.target
= sh
->pd_idx
;
3286 sh
->ops
.target2
= -1;
3291 case check_state_compute_run
:
3294 printk(KERN_ERR
"%s: unknown check_state: %d sector: %llu\n",
3295 __func__
, sh
->check_state
,
3296 (unsigned long long) sh
->sector
);
3301 static void handle_parity_checks6(struct r5conf
*conf
, struct stripe_head
*sh
,
3302 struct stripe_head_state
*s
,
3305 int pd_idx
= sh
->pd_idx
;
3306 int qd_idx
= sh
->qd_idx
;
3309 set_bit(STRIPE_HANDLE
, &sh
->state
);
3311 BUG_ON(s
->failed
> 2);
3313 /* Want to check and possibly repair P and Q.
3314 * However there could be one 'failed' device, in which
3315 * case we can only check one of them, possibly using the
3316 * other to generate missing data
3319 switch (sh
->check_state
) {
3320 case check_state_idle
:
3321 /* start a new check operation if there are < 2 failures */
3322 if (s
->failed
== s
->q_failed
) {
3323 /* The only possible failed device holds Q, so it
3324 * makes sense to check P (If anything else were failed,
3325 * we would have used P to recreate it).
3327 sh
->check_state
= check_state_run
;
3329 if (!s
->q_failed
&& s
->failed
< 2) {
3330 /* Q is not failed, and we didn't use it to generate
3331 * anything, so it makes sense to check it
3333 if (sh
->check_state
== check_state_run
)
3334 sh
->check_state
= check_state_run_pq
;
3336 sh
->check_state
= check_state_run_q
;
3339 /* discard potentially stale zero_sum_result */
3340 sh
->ops
.zero_sum_result
= 0;
3342 if (sh
->check_state
== check_state_run
) {
3343 /* async_xor_zero_sum destroys the contents of P */
3344 clear_bit(R5_UPTODATE
, &sh
->dev
[pd_idx
].flags
);
3347 if (sh
->check_state
>= check_state_run
&&
3348 sh
->check_state
<= check_state_run_pq
) {
3349 /* async_syndrome_zero_sum preserves P and Q, so
3350 * no need to mark them !uptodate here
3352 set_bit(STRIPE_OP_CHECK
, &s
->ops_request
);
3356 /* we have 2-disk failure */
3357 BUG_ON(s
->failed
!= 2);
3359 case check_state_compute_result
:
3360 sh
->check_state
= check_state_idle
;
3362 /* check that a write has not made the stripe insync */
3363 if (test_bit(STRIPE_INSYNC
, &sh
->state
))
3366 /* now write out any block on a failed drive,
3367 * or P or Q if they were recomputed
3369 BUG_ON(s
->uptodate
< disks
- 1); /* We don't need Q to recover */
3370 if (s
->failed
== 2) {
3371 dev
= &sh
->dev
[s
->failed_num
[1]];
3373 set_bit(R5_LOCKED
, &dev
->flags
);
3374 set_bit(R5_Wantwrite
, &dev
->flags
);
3376 if (s
->failed
>= 1) {
3377 dev
= &sh
->dev
[s
->failed_num
[0]];
3379 set_bit(R5_LOCKED
, &dev
->flags
);
3380 set_bit(R5_Wantwrite
, &dev
->flags
);
3382 if (sh
->ops
.zero_sum_result
& SUM_CHECK_P_RESULT
) {
3383 dev
= &sh
->dev
[pd_idx
];
3385 set_bit(R5_LOCKED
, &dev
->flags
);
3386 set_bit(R5_Wantwrite
, &dev
->flags
);
3388 if (sh
->ops
.zero_sum_result
& SUM_CHECK_Q_RESULT
) {
3389 dev
= &sh
->dev
[qd_idx
];
3391 set_bit(R5_LOCKED
, &dev
->flags
);
3392 set_bit(R5_Wantwrite
, &dev
->flags
);
3394 clear_bit(STRIPE_DEGRADED
, &sh
->state
);
3396 set_bit(STRIPE_INSYNC
, &sh
->state
);
3398 case check_state_run
:
3399 case check_state_run_q
:
3400 case check_state_run_pq
:
3401 break; /* we will be called again upon completion */
3402 case check_state_check_result
:
3403 sh
->check_state
= check_state_idle
;
3405 /* handle a successful check operation, if parity is correct
3406 * we are done. Otherwise update the mismatch count and repair
3407 * parity if !MD_RECOVERY_CHECK
3409 if (sh
->ops
.zero_sum_result
== 0) {
3410 /* both parities are correct */
3412 set_bit(STRIPE_INSYNC
, &sh
->state
);
3414 /* in contrast to the raid5 case we can validate
3415 * parity, but still have a failure to write
3418 sh
->check_state
= check_state_compute_result
;
3419 /* Returning at this point means that we may go
3420 * off and bring p and/or q uptodate again so
3421 * we make sure to check zero_sum_result again
3422 * to verify if p or q need writeback
3426 atomic64_add(STRIPE_SECTORS
, &conf
->mddev
->resync_mismatches
);
3427 if (test_bit(MD_RECOVERY_CHECK
, &conf
->mddev
->recovery
))
3428 /* don't try to repair!! */
3429 set_bit(STRIPE_INSYNC
, &sh
->state
);
3431 int *target
= &sh
->ops
.target
;
3433 sh
->ops
.target
= -1;
3434 sh
->ops
.target2
= -1;
3435 sh
->check_state
= check_state_compute_run
;
3436 set_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
3437 set_bit(STRIPE_OP_COMPUTE_BLK
, &s
->ops_request
);
3438 if (sh
->ops
.zero_sum_result
& SUM_CHECK_P_RESULT
) {
3439 set_bit(R5_Wantcompute
,
3440 &sh
->dev
[pd_idx
].flags
);
3442 target
= &sh
->ops
.target2
;
3445 if (sh
->ops
.zero_sum_result
& SUM_CHECK_Q_RESULT
) {
3446 set_bit(R5_Wantcompute
,
3447 &sh
->dev
[qd_idx
].flags
);
3454 case check_state_compute_run
:
3457 printk(KERN_ERR
"%s: unknown check_state: %d sector: %llu\n",
3458 __func__
, sh
->check_state
,
3459 (unsigned long long) sh
->sector
);
3464 static void handle_stripe_expansion(struct r5conf
*conf
, struct stripe_head
*sh
)
3468 /* We have read all the blocks in this stripe and now we need to
3469 * copy some of them into a target stripe for expand.
3471 struct dma_async_tx_descriptor
*tx
= NULL
;
3472 clear_bit(STRIPE_EXPAND_SOURCE
, &sh
->state
);
3473 for (i
= 0; i
< sh
->disks
; i
++)
3474 if (i
!= sh
->pd_idx
&& i
!= sh
->qd_idx
) {
3476 struct stripe_head
*sh2
;
3477 struct async_submit_ctl submit
;
3479 sector_t bn
= compute_blocknr(sh
, i
, 1);
3480 sector_t s
= raid5_compute_sector(conf
, bn
, 0,
3482 sh2
= get_active_stripe(conf
, s
, 0, 1, 1);
3484 /* so far only the early blocks of this stripe
3485 * have been requested. When later blocks
3486 * get requested, we will try again
3489 if (!test_bit(STRIPE_EXPANDING
, &sh2
->state
) ||
3490 test_bit(R5_Expanded
, &sh2
->dev
[dd_idx
].flags
)) {
3491 /* must have already done this block */
3492 release_stripe(sh2
);
3496 /* place all the copies on one channel */
3497 init_async_submit(&submit
, 0, tx
, NULL
, NULL
, NULL
);
3498 tx
= async_memcpy(sh2
->dev
[dd_idx
].page
,
3499 sh
->dev
[i
].page
, 0, 0, STRIPE_SIZE
,
3502 set_bit(R5_Expanded
, &sh2
->dev
[dd_idx
].flags
);
3503 set_bit(R5_UPTODATE
, &sh2
->dev
[dd_idx
].flags
);
3504 for (j
= 0; j
< conf
->raid_disks
; j
++)
3505 if (j
!= sh2
->pd_idx
&&
3507 !test_bit(R5_Expanded
, &sh2
->dev
[j
].flags
))
3509 if (j
== conf
->raid_disks
) {
3510 set_bit(STRIPE_EXPAND_READY
, &sh2
->state
);
3511 set_bit(STRIPE_HANDLE
, &sh2
->state
);
3513 release_stripe(sh2
);
3516 /* done submitting copies, wait for them to complete */
3517 async_tx_quiesce(&tx
);
3521 * handle_stripe - do things to a stripe.
3523 * We lock the stripe by setting STRIPE_ACTIVE and then examine the
3524 * state of various bits to see what needs to be done.
3526 * return some read requests which now have data
3527 * return some write requests which are safely on storage
3528 * schedule a read on some buffers
3529 * schedule a write of some buffers
3530 * return confirmation of parity correctness
3534 static void analyse_stripe(struct stripe_head
*sh
, struct stripe_head_state
*s
)
3536 struct r5conf
*conf
= sh
->raid_conf
;
3537 int disks
= sh
->disks
;
3540 int do_recovery
= 0;
3542 memset(s
, 0, sizeof(*s
));
3544 s
->expanding
= test_bit(STRIPE_EXPAND_SOURCE
, &sh
->state
);
3545 s
->expanded
= test_bit(STRIPE_EXPAND_READY
, &sh
->state
);
3546 s
->failed_num
[0] = -1;
3547 s
->failed_num
[1] = -1;
3549 /* Now to look around and see what can be done */
3551 for (i
=disks
; i
--; ) {
3552 struct md_rdev
*rdev
;
3559 pr_debug("check %d: state 0x%lx read %p write %p written %p\n",
3561 dev
->toread
, dev
->towrite
, dev
->written
);
3562 /* maybe we can reply to a read
3564 * new wantfill requests are only permitted while
3565 * ops_complete_biofill is guaranteed to be inactive
3567 if (test_bit(R5_UPTODATE
, &dev
->flags
) && dev
->toread
&&
3568 !test_bit(STRIPE_BIOFILL_RUN
, &sh
->state
))
3569 set_bit(R5_Wantfill
, &dev
->flags
);
3571 /* now count some things */
3572 if (test_bit(R5_LOCKED
, &dev
->flags
))
3574 if (test_bit(R5_UPTODATE
, &dev
->flags
))
3576 if (test_bit(R5_Wantcompute
, &dev
->flags
)) {
3578 BUG_ON(s
->compute
> 2);
3581 if (test_bit(R5_Wantfill
, &dev
->flags
))
3583 else if (dev
->toread
)
3587 if (!test_bit(R5_OVERWRITE
, &dev
->flags
))
3592 /* Prefer to use the replacement for reads, but only
3593 * if it is recovered enough and has no bad blocks.
3595 rdev
= rcu_dereference(conf
->disks
[i
].replacement
);
3596 if (rdev
&& !test_bit(Faulty
, &rdev
->flags
) &&
3597 rdev
->recovery_offset
>= sh
->sector
+ STRIPE_SECTORS
&&
3598 !is_badblock(rdev
, sh
->sector
, STRIPE_SECTORS
,
3599 &first_bad
, &bad_sectors
))
3600 set_bit(R5_ReadRepl
, &dev
->flags
);
3603 set_bit(R5_NeedReplace
, &dev
->flags
);
3604 rdev
= rcu_dereference(conf
->disks
[i
].rdev
);
3605 clear_bit(R5_ReadRepl
, &dev
->flags
);
3607 if (rdev
&& test_bit(Faulty
, &rdev
->flags
))
3610 is_bad
= is_badblock(rdev
, sh
->sector
, STRIPE_SECTORS
,
3611 &first_bad
, &bad_sectors
);
3612 if (s
->blocked_rdev
== NULL
3613 && (test_bit(Blocked
, &rdev
->flags
)
3616 set_bit(BlockedBadBlocks
,
3618 s
->blocked_rdev
= rdev
;
3619 atomic_inc(&rdev
->nr_pending
);
3622 clear_bit(R5_Insync
, &dev
->flags
);
3626 /* also not in-sync */
3627 if (!test_bit(WriteErrorSeen
, &rdev
->flags
) &&
3628 test_bit(R5_UPTODATE
, &dev
->flags
)) {
3629 /* treat as in-sync, but with a read error
3630 * which we can now try to correct
3632 set_bit(R5_Insync
, &dev
->flags
);
3633 set_bit(R5_ReadError
, &dev
->flags
);
3635 } else if (test_bit(In_sync
, &rdev
->flags
))
3636 set_bit(R5_Insync
, &dev
->flags
);
3637 else if (sh
->sector
+ STRIPE_SECTORS
<= rdev
->recovery_offset
)
3638 /* in sync if before recovery_offset */
3639 set_bit(R5_Insync
, &dev
->flags
);
3640 else if (test_bit(R5_UPTODATE
, &dev
->flags
) &&
3641 test_bit(R5_Expanded
, &dev
->flags
))
3642 /* If we've reshaped into here, we assume it is Insync.
3643 * We will shortly update recovery_offset to make
3646 set_bit(R5_Insync
, &dev
->flags
);
3648 if (test_bit(R5_WriteError
, &dev
->flags
)) {
3649 /* This flag does not apply to '.replacement'
3650 * only to .rdev, so make sure to check that*/
3651 struct md_rdev
*rdev2
= rcu_dereference(
3652 conf
->disks
[i
].rdev
);
3654 clear_bit(R5_Insync
, &dev
->flags
);
3655 if (rdev2
&& !test_bit(Faulty
, &rdev2
->flags
)) {
3656 s
->handle_bad_blocks
= 1;
3657 atomic_inc(&rdev2
->nr_pending
);
3659 clear_bit(R5_WriteError
, &dev
->flags
);
3661 if (test_bit(R5_MadeGood
, &dev
->flags
)) {
3662 /* This flag does not apply to '.replacement'
3663 * only to .rdev, so make sure to check that*/
3664 struct md_rdev
*rdev2
= rcu_dereference(
3665 conf
->disks
[i
].rdev
);
3666 if (rdev2
&& !test_bit(Faulty
, &rdev2
->flags
)) {
3667 s
->handle_bad_blocks
= 1;
3668 atomic_inc(&rdev2
->nr_pending
);
3670 clear_bit(R5_MadeGood
, &dev
->flags
);
3672 if (test_bit(R5_MadeGoodRepl
, &dev
->flags
)) {
3673 struct md_rdev
*rdev2
= rcu_dereference(
3674 conf
->disks
[i
].replacement
);
3675 if (rdev2
&& !test_bit(Faulty
, &rdev2
->flags
)) {
3676 s
->handle_bad_blocks
= 1;
3677 atomic_inc(&rdev2
->nr_pending
);
3679 clear_bit(R5_MadeGoodRepl
, &dev
->flags
);
3681 if (!test_bit(R5_Insync
, &dev
->flags
)) {
3682 /* The ReadError flag will just be confusing now */
3683 clear_bit(R5_ReadError
, &dev
->flags
);
3684 clear_bit(R5_ReWrite
, &dev
->flags
);
3686 if (test_bit(R5_ReadError
, &dev
->flags
))
3687 clear_bit(R5_Insync
, &dev
->flags
);
3688 if (!test_bit(R5_Insync
, &dev
->flags
)) {
3690 s
->failed_num
[s
->failed
] = i
;
3692 if (rdev
&& !test_bit(Faulty
, &rdev
->flags
))
3696 if (test_bit(STRIPE_SYNCING
, &sh
->state
)) {
3697 /* If there is a failed device being replaced,
3698 * we must be recovering.
3699 * else if we are after recovery_cp, we must be syncing
3700 * else if MD_RECOVERY_REQUESTED is set, we also are syncing.
3701 * else we can only be replacing
3702 * sync and recovery both need to read all devices, and so
3703 * use the same flag.
3706 sh
->sector
>= conf
->mddev
->recovery_cp
||
3707 test_bit(MD_RECOVERY_REQUESTED
, &(conf
->mddev
->recovery
)))
3715 static void handle_stripe(struct stripe_head
*sh
)
3717 struct stripe_head_state s
;
3718 struct r5conf
*conf
= sh
->raid_conf
;
3721 int disks
= sh
->disks
;
3722 struct r5dev
*pdev
, *qdev
;
3724 clear_bit(STRIPE_HANDLE
, &sh
->state
);
3725 if (test_and_set_bit_lock(STRIPE_ACTIVE
, &sh
->state
)) {
3726 /* already being handled, ensure it gets handled
3727 * again when current action finishes */
3728 set_bit(STRIPE_HANDLE
, &sh
->state
);
3732 if (test_bit(STRIPE_SYNC_REQUESTED
, &sh
->state
)) {
3733 spin_lock(&sh
->stripe_lock
);
3734 /* Cannot process 'sync' concurrently with 'discard' */
3735 if (!test_bit(STRIPE_DISCARD
, &sh
->state
) &&
3736 test_and_clear_bit(STRIPE_SYNC_REQUESTED
, &sh
->state
)) {
3737 set_bit(STRIPE_SYNCING
, &sh
->state
);
3738 clear_bit(STRIPE_INSYNC
, &sh
->state
);
3739 clear_bit(STRIPE_REPLACED
, &sh
->state
);
3741 spin_unlock(&sh
->stripe_lock
);
3743 clear_bit(STRIPE_DELAYED
, &sh
->state
);
3745 pr_debug("handling stripe %llu, state=%#lx cnt=%d, "
3746 "pd_idx=%d, qd_idx=%d\n, check:%d, reconstruct:%d\n",
3747 (unsigned long long)sh
->sector
, sh
->state
,
3748 atomic_read(&sh
->count
), sh
->pd_idx
, sh
->qd_idx
,
3749 sh
->check_state
, sh
->reconstruct_state
);
3751 analyse_stripe(sh
, &s
);
3753 if (s
.handle_bad_blocks
) {
3754 set_bit(STRIPE_HANDLE
, &sh
->state
);
3758 if (unlikely(s
.blocked_rdev
)) {
3759 if (s
.syncing
|| s
.expanding
|| s
.expanded
||
3760 s
.replacing
|| s
.to_write
|| s
.written
) {
3761 set_bit(STRIPE_HANDLE
, &sh
->state
);
3764 /* There is nothing for the blocked_rdev to block */
3765 rdev_dec_pending(s
.blocked_rdev
, conf
->mddev
);
3766 s
.blocked_rdev
= NULL
;
3769 if (s
.to_fill
&& !test_bit(STRIPE_BIOFILL_RUN
, &sh
->state
)) {
3770 set_bit(STRIPE_OP_BIOFILL
, &s
.ops_request
);
3771 set_bit(STRIPE_BIOFILL_RUN
, &sh
->state
);
3774 pr_debug("locked=%d uptodate=%d to_read=%d"
3775 " to_write=%d failed=%d failed_num=%d,%d\n",
3776 s
.locked
, s
.uptodate
, s
.to_read
, s
.to_write
, s
.failed
,
3777 s
.failed_num
[0], s
.failed_num
[1]);
3778 /* check if the array has lost more than max_degraded devices and,
3779 * if so, some requests might need to be failed.
3781 if (s
.failed
> conf
->max_degraded
) {
3782 sh
->check_state
= 0;
3783 sh
->reconstruct_state
= 0;
3784 if (s
.to_read
+s
.to_write
+s
.written
)
3785 handle_failed_stripe(conf
, sh
, &s
, disks
, &s
.return_bi
);
3786 if (s
.syncing
+ s
.replacing
)
3787 handle_failed_sync(conf
, sh
, &s
);
3790 /* Now we check to see if any write operations have recently
3794 if (sh
->reconstruct_state
== reconstruct_state_prexor_drain_result
)
3796 if (sh
->reconstruct_state
== reconstruct_state_drain_result
||
3797 sh
->reconstruct_state
== reconstruct_state_prexor_drain_result
) {
3798 sh
->reconstruct_state
= reconstruct_state_idle
;
3800 /* All the 'written' buffers and the parity block are ready to
3801 * be written back to disk
3803 BUG_ON(!test_bit(R5_UPTODATE
, &sh
->dev
[sh
->pd_idx
].flags
) &&
3804 !test_bit(R5_Discard
, &sh
->dev
[sh
->pd_idx
].flags
));
3805 BUG_ON(sh
->qd_idx
>= 0 &&
3806 !test_bit(R5_UPTODATE
, &sh
->dev
[sh
->qd_idx
].flags
) &&
3807 !test_bit(R5_Discard
, &sh
->dev
[sh
->qd_idx
].flags
));
3808 for (i
= disks
; i
--; ) {
3809 struct r5dev
*dev
= &sh
->dev
[i
];
3810 if (test_bit(R5_LOCKED
, &dev
->flags
) &&
3811 (i
== sh
->pd_idx
|| i
== sh
->qd_idx
||
3813 pr_debug("Writing block %d\n", i
);
3814 set_bit(R5_Wantwrite
, &dev
->flags
);
3819 if (!test_bit(R5_Insync
, &dev
->flags
) ||
3820 ((i
== sh
->pd_idx
|| i
== sh
->qd_idx
) &&
3822 set_bit(STRIPE_INSYNC
, &sh
->state
);
3825 if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
3826 s
.dec_preread_active
= 1;
3830 * might be able to return some write requests if the parity blocks
3831 * are safe, or on a failed drive
3833 pdev
= &sh
->dev
[sh
->pd_idx
];
3834 s
.p_failed
= (s
.failed
>= 1 && s
.failed_num
[0] == sh
->pd_idx
)
3835 || (s
.failed
>= 2 && s
.failed_num
[1] == sh
->pd_idx
);
3836 qdev
= &sh
->dev
[sh
->qd_idx
];
3837 s
.q_failed
= (s
.failed
>= 1 && s
.failed_num
[0] == sh
->qd_idx
)
3838 || (s
.failed
>= 2 && s
.failed_num
[1] == sh
->qd_idx
)
3842 (s
.p_failed
|| ((test_bit(R5_Insync
, &pdev
->flags
)
3843 && !test_bit(R5_LOCKED
, &pdev
->flags
)
3844 && (test_bit(R5_UPTODATE
, &pdev
->flags
) ||
3845 test_bit(R5_Discard
, &pdev
->flags
))))) &&
3846 (s
.q_failed
|| ((test_bit(R5_Insync
, &qdev
->flags
)
3847 && !test_bit(R5_LOCKED
, &qdev
->flags
)
3848 && (test_bit(R5_UPTODATE
, &qdev
->flags
) ||
3849 test_bit(R5_Discard
, &qdev
->flags
))))))
3850 handle_stripe_clean_event(conf
, sh
, disks
, &s
.return_bi
);
3852 /* Now we might consider reading some blocks, either to check/generate
3853 * parity, or to satisfy requests
3854 * or to load a block that is being partially written.
3856 if (s
.to_read
|| s
.non_overwrite
3857 || (conf
->level
== 6 && s
.to_write
&& s
.failed
)
3858 || (s
.syncing
&& (s
.uptodate
+ s
.compute
< disks
))
3861 handle_stripe_fill(sh
, &s
, disks
);
3863 /* Now to consider new write requests and what else, if anything
3864 * should be read. We do not handle new writes when:
3865 * 1/ A 'write' operation (copy+xor) is already in flight.
3866 * 2/ A 'check' operation is in flight, as it may clobber the parity
3869 if (s
.to_write
&& !sh
->reconstruct_state
&& !sh
->check_state
)
3870 handle_stripe_dirtying(conf
, sh
, &s
, disks
);
3872 /* maybe we need to check and possibly fix the parity for this stripe
3873 * Any reads will already have been scheduled, so we just see if enough
3874 * data is available. The parity check is held off while parity
3875 * dependent operations are in flight.
3877 if (sh
->check_state
||
3878 (s
.syncing
&& s
.locked
== 0 &&
3879 !test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
) &&
3880 !test_bit(STRIPE_INSYNC
, &sh
->state
))) {
3881 if (conf
->level
== 6)
3882 handle_parity_checks6(conf
, sh
, &s
, disks
);
3884 handle_parity_checks5(conf
, sh
, &s
, disks
);
3887 if ((s
.replacing
|| s
.syncing
) && s
.locked
== 0
3888 && !test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
)
3889 && !test_bit(STRIPE_REPLACED
, &sh
->state
)) {
3890 /* Write out to replacement devices where possible */
3891 for (i
= 0; i
< conf
->raid_disks
; i
++)
3892 if (test_bit(R5_NeedReplace
, &sh
->dev
[i
].flags
)) {
3893 WARN_ON(!test_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
));
3894 set_bit(R5_WantReplace
, &sh
->dev
[i
].flags
);
3895 set_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
3899 set_bit(STRIPE_INSYNC
, &sh
->state
);
3900 set_bit(STRIPE_REPLACED
, &sh
->state
);
3902 if ((s
.syncing
|| s
.replacing
) && s
.locked
== 0 &&
3903 !test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
) &&
3904 test_bit(STRIPE_INSYNC
, &sh
->state
)) {
3905 md_done_sync(conf
->mddev
, STRIPE_SECTORS
, 1);
3906 clear_bit(STRIPE_SYNCING
, &sh
->state
);
3907 if (test_and_clear_bit(R5_Overlap
, &sh
->dev
[sh
->pd_idx
].flags
))
3908 wake_up(&conf
->wait_for_overlap
);
3911 /* If the failed drives are just a ReadError, then we might need
3912 * to progress the repair/check process
3914 if (s
.failed
<= conf
->max_degraded
&& !conf
->mddev
->ro
)
3915 for (i
= 0; i
< s
.failed
; i
++) {
3916 struct r5dev
*dev
= &sh
->dev
[s
.failed_num
[i
]];
3917 if (test_bit(R5_ReadError
, &dev
->flags
)
3918 && !test_bit(R5_LOCKED
, &dev
->flags
)
3919 && test_bit(R5_UPTODATE
, &dev
->flags
)
3921 if (!test_bit(R5_ReWrite
, &dev
->flags
)) {
3922 set_bit(R5_Wantwrite
, &dev
->flags
);
3923 set_bit(R5_ReWrite
, &dev
->flags
);
3924 set_bit(R5_LOCKED
, &dev
->flags
);
3927 /* let's read it back */
3928 set_bit(R5_Wantread
, &dev
->flags
);
3929 set_bit(R5_LOCKED
, &dev
->flags
);
3935 /* Finish reconstruct operations initiated by the expansion process */
3936 if (sh
->reconstruct_state
== reconstruct_state_result
) {
3937 struct stripe_head
*sh_src
3938 = get_active_stripe(conf
, sh
->sector
, 1, 1, 1);
3939 if (sh_src
&& test_bit(STRIPE_EXPAND_SOURCE
, &sh_src
->state
)) {
3940 /* sh cannot be written until sh_src has been read.
3941 * so arrange for sh to be delayed a little
3943 set_bit(STRIPE_DELAYED
, &sh
->state
);
3944 set_bit(STRIPE_HANDLE
, &sh
->state
);
3945 if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE
,
3947 atomic_inc(&conf
->preread_active_stripes
);
3948 release_stripe(sh_src
);
3952 release_stripe(sh_src
);
3954 sh
->reconstruct_state
= reconstruct_state_idle
;
3955 clear_bit(STRIPE_EXPANDING
, &sh
->state
);
3956 for (i
= conf
->raid_disks
; i
--; ) {
3957 set_bit(R5_Wantwrite
, &sh
->dev
[i
].flags
);
3958 set_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
3963 if (s
.expanded
&& test_bit(STRIPE_EXPANDING
, &sh
->state
) &&
3964 !sh
->reconstruct_state
) {
3965 /* Need to write out all blocks after computing parity */
3966 sh
->disks
= conf
->raid_disks
;
3967 stripe_set_idx(sh
->sector
, conf
, 0, sh
);
3968 schedule_reconstruction(sh
, &s
, 1, 1);
3969 } else if (s
.expanded
&& !sh
->reconstruct_state
&& s
.locked
== 0) {
3970 clear_bit(STRIPE_EXPAND_READY
, &sh
->state
);
3971 atomic_dec(&conf
->reshape_stripes
);
3972 wake_up(&conf
->wait_for_overlap
);
3973 md_done_sync(conf
->mddev
, STRIPE_SECTORS
, 1);
3976 if (s
.expanding
&& s
.locked
== 0 &&
3977 !test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
))
3978 handle_stripe_expansion(conf
, sh
);
3981 /* wait for this device to become unblocked */
3982 if (unlikely(s
.blocked_rdev
)) {
3983 if (conf
->mddev
->external
)
3984 md_wait_for_blocked_rdev(s
.blocked_rdev
,
3987 /* Internal metadata will immediately
3988 * be written by raid5d, so we don't
3989 * need to wait here.
3991 rdev_dec_pending(s
.blocked_rdev
,
3995 if (s
.handle_bad_blocks
)
3996 for (i
= disks
; i
--; ) {
3997 struct md_rdev
*rdev
;
3998 struct r5dev
*dev
= &sh
->dev
[i
];
3999 if (test_and_clear_bit(R5_WriteError
, &dev
->flags
)) {
4000 /* We own a safe reference to the rdev */
4001 rdev
= conf
->disks
[i
].rdev
;
4002 if (!rdev_set_badblocks(rdev
, sh
->sector
,
4004 md_error(conf
->mddev
, rdev
);
4005 rdev_dec_pending(rdev
, conf
->mddev
);
4007 if (test_and_clear_bit(R5_MadeGood
, &dev
->flags
)) {
4008 rdev
= conf
->disks
[i
].rdev
;
4009 rdev_clear_badblocks(rdev
, sh
->sector
,
4011 rdev_dec_pending(rdev
, conf
->mddev
);
4013 if (test_and_clear_bit(R5_MadeGoodRepl
, &dev
->flags
)) {
4014 rdev
= conf
->disks
[i
].replacement
;
4016 /* rdev have been moved down */
4017 rdev
= conf
->disks
[i
].rdev
;
4018 rdev_clear_badblocks(rdev
, sh
->sector
,
4020 rdev_dec_pending(rdev
, conf
->mddev
);
4025 raid_run_ops(sh
, s
.ops_request
);
4029 if (s
.dec_preread_active
) {
4030 /* We delay this until after ops_run_io so that if make_request
4031 * is waiting on a flush, it won't continue until the writes
4032 * have actually been submitted.
4034 atomic_dec(&conf
->preread_active_stripes
);
4035 if (atomic_read(&conf
->preread_active_stripes
) <
4037 md_wakeup_thread(conf
->mddev
->thread
);
4040 return_io(s
.return_bi
);
4042 clear_bit_unlock(STRIPE_ACTIVE
, &sh
->state
);
4045 static void raid5_activate_delayed(struct r5conf
*conf
)
4047 if (atomic_read(&conf
->preread_active_stripes
) < IO_THRESHOLD
) {
4048 while (!list_empty(&conf
->delayed_list
)) {
4049 struct list_head
*l
= conf
->delayed_list
.next
;
4050 struct stripe_head
*sh
;
4051 sh
= list_entry(l
, struct stripe_head
, lru
);
4053 clear_bit(STRIPE_DELAYED
, &sh
->state
);
4054 if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
4055 atomic_inc(&conf
->preread_active_stripes
);
4056 list_add_tail(&sh
->lru
, &conf
->hold_list
);
4057 raid5_wakeup_stripe_thread(sh
);
4062 static void activate_bit_delay(struct r5conf
*conf
,
4063 struct list_head
*temp_inactive_list
)
4065 /* device_lock is held */
4066 struct list_head head
;
4067 list_add(&head
, &conf
->bitmap_list
);
4068 list_del_init(&conf
->bitmap_list
);
4069 while (!list_empty(&head
)) {
4070 struct stripe_head
*sh
= list_entry(head
.next
, struct stripe_head
, lru
);
4072 list_del_init(&sh
->lru
);
4073 atomic_inc(&sh
->count
);
4074 hash
= sh
->hash_lock_index
;
4075 __release_stripe(conf
, sh
, &temp_inactive_list
[hash
]);
4079 int md_raid5_congested(struct mddev
*mddev
, int bits
)
4081 struct r5conf
*conf
= mddev
->private;
4083 /* No difference between reads and writes. Just check
4084 * how busy the stripe_cache is
4087 if (conf
->inactive_blocked
)
4091 if (atomic_read(&conf
->empty_inactive_list_nr
))
4096 EXPORT_SYMBOL_GPL(md_raid5_congested
);
4098 static int raid5_congested(void *data
, int bits
)
4100 struct mddev
*mddev
= data
;
4102 return mddev_congested(mddev
, bits
) ||
4103 md_raid5_congested(mddev
, bits
);
4106 /* We want read requests to align with chunks where possible,
4107 * but write requests don't need to.
4109 static int raid5_mergeable_bvec(struct request_queue
*q
,
4110 struct bvec_merge_data
*bvm
,
4111 struct bio_vec
*biovec
)
4113 struct mddev
*mddev
= q
->queuedata
;
4114 sector_t sector
= bvm
->bi_sector
+ get_start_sect(bvm
->bi_bdev
);
4116 unsigned int chunk_sectors
= mddev
->chunk_sectors
;
4117 unsigned int bio_sectors
= bvm
->bi_size
>> 9;
4119 if ((bvm
->bi_rw
& 1) == WRITE
)
4120 return biovec
->bv_len
; /* always allow writes to be mergeable */
4122 if (mddev
->new_chunk_sectors
< mddev
->chunk_sectors
)
4123 chunk_sectors
= mddev
->new_chunk_sectors
;
4124 max
= (chunk_sectors
- ((sector
& (chunk_sectors
- 1)) + bio_sectors
)) << 9;
4125 if (max
< 0) max
= 0;
4126 if (max
<= biovec
->bv_len
&& bio_sectors
== 0)
4127 return biovec
->bv_len
;
4132 static int in_chunk_boundary(struct mddev
*mddev
, struct bio
*bio
)
4134 sector_t sector
= bio
->bi_iter
.bi_sector
+ get_start_sect(bio
->bi_bdev
);
4135 unsigned int chunk_sectors
= mddev
->chunk_sectors
;
4136 unsigned int bio_sectors
= bio_sectors(bio
);
4138 if (mddev
->new_chunk_sectors
< mddev
->chunk_sectors
)
4139 chunk_sectors
= mddev
->new_chunk_sectors
;
4140 return chunk_sectors
>=
4141 ((sector
& (chunk_sectors
- 1)) + bio_sectors
);
4145 * add bio to the retry LIFO ( in O(1) ... we are in interrupt )
4146 * later sampled by raid5d.
4148 static void add_bio_to_retry(struct bio
*bi
,struct r5conf
*conf
)
4150 unsigned long flags
;
4152 spin_lock_irqsave(&conf
->device_lock
, flags
);
4154 bi
->bi_next
= conf
->retry_read_aligned_list
;
4155 conf
->retry_read_aligned_list
= bi
;
4157 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
4158 md_wakeup_thread(conf
->mddev
->thread
);
4161 static struct bio
*remove_bio_from_retry(struct r5conf
*conf
)
4165 bi
= conf
->retry_read_aligned
;
4167 conf
->retry_read_aligned
= NULL
;
4170 bi
= conf
->retry_read_aligned_list
;
4172 conf
->retry_read_aligned_list
= bi
->bi_next
;
4175 * this sets the active strip count to 1 and the processed
4176 * strip count to zero (upper 8 bits)
4178 raid5_set_bi_stripes(bi
, 1); /* biased count of active stripes */
4185 * The "raid5_align_endio" should check if the read succeeded and if it
4186 * did, call bio_endio on the original bio (having bio_put the new bio
4188 * If the read failed..
4190 static void raid5_align_endio(struct bio
*bi
, int error
)
4192 struct bio
* raid_bi
= bi
->bi_private
;
4193 struct mddev
*mddev
;
4194 struct r5conf
*conf
;
4195 int uptodate
= test_bit(BIO_UPTODATE
, &bi
->bi_flags
);
4196 struct md_rdev
*rdev
;
4200 rdev
= (void*)raid_bi
->bi_next
;
4201 raid_bi
->bi_next
= NULL
;
4202 mddev
= rdev
->mddev
;
4203 conf
= mddev
->private;
4205 rdev_dec_pending(rdev
, conf
->mddev
);
4207 if (!error
&& uptodate
) {
4208 trace_block_bio_complete(bdev_get_queue(raid_bi
->bi_bdev
),
4210 bio_endio(raid_bi
, 0);
4211 if (atomic_dec_and_test(&conf
->active_aligned_reads
))
4212 wake_up(&conf
->wait_for_stripe
);
4216 pr_debug("raid5_align_endio : io error...handing IO for a retry\n");
4218 add_bio_to_retry(raid_bi
, conf
);
4221 static int bio_fits_rdev(struct bio
*bi
)
4223 struct request_queue
*q
= bdev_get_queue(bi
->bi_bdev
);
4225 if (bio_sectors(bi
) > queue_max_sectors(q
))
4227 blk_recount_segments(q
, bi
);
4228 if (bi
->bi_phys_segments
> queue_max_segments(q
))
4231 if (q
->merge_bvec_fn
)
4232 /* it's too hard to apply the merge_bvec_fn at this stage,
4240 static int chunk_aligned_read(struct mddev
*mddev
, struct bio
* raid_bio
)
4242 struct r5conf
*conf
= mddev
->private;
4244 struct bio
* align_bi
;
4245 struct md_rdev
*rdev
;
4246 sector_t end_sector
;
4248 if (!in_chunk_boundary(mddev
, raid_bio
)) {
4249 pr_debug("chunk_aligned_read : non aligned\n");
4253 * use bio_clone_mddev to make a copy of the bio
4255 align_bi
= bio_clone_mddev(raid_bio
, GFP_NOIO
, mddev
);
4259 * set bi_end_io to a new function, and set bi_private to the
4262 align_bi
->bi_end_io
= raid5_align_endio
;
4263 align_bi
->bi_private
= raid_bio
;
4267 align_bi
->bi_iter
.bi_sector
=
4268 raid5_compute_sector(conf
, raid_bio
->bi_iter
.bi_sector
,
4271 end_sector
= bio_end_sector(align_bi
);
4273 rdev
= rcu_dereference(conf
->disks
[dd_idx
].replacement
);
4274 if (!rdev
|| test_bit(Faulty
, &rdev
->flags
) ||
4275 rdev
->recovery_offset
< end_sector
) {
4276 rdev
= rcu_dereference(conf
->disks
[dd_idx
].rdev
);
4278 (test_bit(Faulty
, &rdev
->flags
) ||
4279 !(test_bit(In_sync
, &rdev
->flags
) ||
4280 rdev
->recovery_offset
>= end_sector
)))
4287 atomic_inc(&rdev
->nr_pending
);
4289 raid_bio
->bi_next
= (void*)rdev
;
4290 align_bi
->bi_bdev
= rdev
->bdev
;
4291 __clear_bit(BIO_SEG_VALID
, &align_bi
->bi_flags
);
4293 if (!bio_fits_rdev(align_bi
) ||
4294 is_badblock(rdev
, align_bi
->bi_iter
.bi_sector
,
4295 bio_sectors(align_bi
),
4296 &first_bad
, &bad_sectors
)) {
4297 /* too big in some way, or has a known bad block */
4299 rdev_dec_pending(rdev
, mddev
);
4303 /* No reshape active, so we can trust rdev->data_offset */
4304 align_bi
->bi_iter
.bi_sector
+= rdev
->data_offset
;
4306 spin_lock_irq(&conf
->device_lock
);
4307 wait_event_lock_irq(conf
->wait_for_stripe
,
4310 atomic_inc(&conf
->active_aligned_reads
);
4311 spin_unlock_irq(&conf
->device_lock
);
4314 trace_block_bio_remap(bdev_get_queue(align_bi
->bi_bdev
),
4315 align_bi
, disk_devt(mddev
->gendisk
),
4316 raid_bio
->bi_iter
.bi_sector
);
4317 generic_make_request(align_bi
);
4326 /* __get_priority_stripe - get the next stripe to process
4328 * Full stripe writes are allowed to pass preread active stripes up until
4329 * the bypass_threshold is exceeded. In general the bypass_count
4330 * increments when the handle_list is handled before the hold_list; however, it
4331 * will not be incremented when STRIPE_IO_STARTED is sampled set signifying a
4332 * stripe with in flight i/o. The bypass_count will be reset when the
4333 * head of the hold_list has changed, i.e. the head was promoted to the
4336 static struct stripe_head
*__get_priority_stripe(struct r5conf
*conf
, int group
)
4338 struct stripe_head
*sh
= NULL
, *tmp
;
4339 struct list_head
*handle_list
= NULL
;
4340 struct r5worker_group
*wg
= NULL
;
4342 if (conf
->worker_cnt_per_group
== 0) {
4343 handle_list
= &conf
->handle_list
;
4344 } else if (group
!= ANY_GROUP
) {
4345 handle_list
= &conf
->worker_groups
[group
].handle_list
;
4346 wg
= &conf
->worker_groups
[group
];
4349 for (i
= 0; i
< conf
->group_cnt
; i
++) {
4350 handle_list
= &conf
->worker_groups
[i
].handle_list
;
4351 wg
= &conf
->worker_groups
[i
];
4352 if (!list_empty(handle_list
))
4357 pr_debug("%s: handle: %s hold: %s full_writes: %d bypass_count: %d\n",
4359 list_empty(handle_list
) ? "empty" : "busy",
4360 list_empty(&conf
->hold_list
) ? "empty" : "busy",
4361 atomic_read(&conf
->pending_full_writes
), conf
->bypass_count
);
4363 if (!list_empty(handle_list
)) {
4364 sh
= list_entry(handle_list
->next
, typeof(*sh
), lru
);
4366 if (list_empty(&conf
->hold_list
))
4367 conf
->bypass_count
= 0;
4368 else if (!test_bit(STRIPE_IO_STARTED
, &sh
->state
)) {
4369 if (conf
->hold_list
.next
== conf
->last_hold
)
4370 conf
->bypass_count
++;
4372 conf
->last_hold
= conf
->hold_list
.next
;
4373 conf
->bypass_count
-= conf
->bypass_threshold
;
4374 if (conf
->bypass_count
< 0)
4375 conf
->bypass_count
= 0;
4378 } else if (!list_empty(&conf
->hold_list
) &&
4379 ((conf
->bypass_threshold
&&
4380 conf
->bypass_count
> conf
->bypass_threshold
) ||
4381 atomic_read(&conf
->pending_full_writes
) == 0)) {
4383 list_for_each_entry(tmp
, &conf
->hold_list
, lru
) {
4384 if (conf
->worker_cnt_per_group
== 0 ||
4385 group
== ANY_GROUP
||
4386 !cpu_online(tmp
->cpu
) ||
4387 cpu_to_group(tmp
->cpu
) == group
) {
4394 conf
->bypass_count
-= conf
->bypass_threshold
;
4395 if (conf
->bypass_count
< 0)
4396 conf
->bypass_count
= 0;
4408 list_del_init(&sh
->lru
);
4409 BUG_ON(atomic_inc_return(&sh
->count
) != 1);
4413 struct raid5_plug_cb
{
4414 struct blk_plug_cb cb
;
4415 struct list_head list
;
4416 struct list_head temp_inactive_list
[NR_STRIPE_HASH_LOCKS
];
4419 static void raid5_unplug(struct blk_plug_cb
*blk_cb
, bool from_schedule
)
4421 struct raid5_plug_cb
*cb
= container_of(
4422 blk_cb
, struct raid5_plug_cb
, cb
);
4423 struct stripe_head
*sh
;
4424 struct mddev
*mddev
= cb
->cb
.data
;
4425 struct r5conf
*conf
= mddev
->private;
4429 if (cb
->list
.next
&& !list_empty(&cb
->list
)) {
4430 spin_lock_irq(&conf
->device_lock
);
4431 while (!list_empty(&cb
->list
)) {
4432 sh
= list_first_entry(&cb
->list
, struct stripe_head
, lru
);
4433 list_del_init(&sh
->lru
);
4435 * avoid race release_stripe_plug() sees
4436 * STRIPE_ON_UNPLUG_LIST clear but the stripe
4437 * is still in our list
4439 smp_mb__before_atomic();
4440 clear_bit(STRIPE_ON_UNPLUG_LIST
, &sh
->state
);
4442 * STRIPE_ON_RELEASE_LIST could be set here. In that
4443 * case, the count is always > 1 here
4445 hash
= sh
->hash_lock_index
;
4446 __release_stripe(conf
, sh
, &cb
->temp_inactive_list
[hash
]);
4449 spin_unlock_irq(&conf
->device_lock
);
4451 release_inactive_stripe_list(conf
, cb
->temp_inactive_list
,
4452 NR_STRIPE_HASH_LOCKS
);
4454 trace_block_unplug(mddev
->queue
, cnt
, !from_schedule
);
4458 static void release_stripe_plug(struct mddev
*mddev
,
4459 struct stripe_head
*sh
)
4461 struct blk_plug_cb
*blk_cb
= blk_check_plugged(
4462 raid5_unplug
, mddev
,
4463 sizeof(struct raid5_plug_cb
));
4464 struct raid5_plug_cb
*cb
;
4471 cb
= container_of(blk_cb
, struct raid5_plug_cb
, cb
);
4473 if (cb
->list
.next
== NULL
) {
4475 INIT_LIST_HEAD(&cb
->list
);
4476 for (i
= 0; i
< NR_STRIPE_HASH_LOCKS
; i
++)
4477 INIT_LIST_HEAD(cb
->temp_inactive_list
+ i
);
4480 if (!test_and_set_bit(STRIPE_ON_UNPLUG_LIST
, &sh
->state
))
4481 list_add_tail(&sh
->lru
, &cb
->list
);
4486 static void make_discard_request(struct mddev
*mddev
, struct bio
*bi
)
4488 struct r5conf
*conf
= mddev
->private;
4489 sector_t logical_sector
, last_sector
;
4490 struct stripe_head
*sh
;
4494 if (mddev
->reshape_position
!= MaxSector
)
4495 /* Skip discard while reshape is happening */
4498 logical_sector
= bi
->bi_iter
.bi_sector
& ~((sector_t
)STRIPE_SECTORS
-1);
4499 last_sector
= bi
->bi_iter
.bi_sector
+ (bi
->bi_iter
.bi_size
>>9);
4502 bi
->bi_phys_segments
= 1; /* over-loaded to count active stripes */
4504 stripe_sectors
= conf
->chunk_sectors
*
4505 (conf
->raid_disks
- conf
->max_degraded
);
4506 logical_sector
= DIV_ROUND_UP_SECTOR_T(logical_sector
,
4508 sector_div(last_sector
, stripe_sectors
);
4510 logical_sector
*= conf
->chunk_sectors
;
4511 last_sector
*= conf
->chunk_sectors
;
4513 for (; logical_sector
< last_sector
;
4514 logical_sector
+= STRIPE_SECTORS
) {
4518 sh
= get_active_stripe(conf
, logical_sector
, 0, 0, 0);
4519 prepare_to_wait(&conf
->wait_for_overlap
, &w
,
4520 TASK_UNINTERRUPTIBLE
);
4521 set_bit(R5_Overlap
, &sh
->dev
[sh
->pd_idx
].flags
);
4522 if (test_bit(STRIPE_SYNCING
, &sh
->state
)) {
4527 clear_bit(R5_Overlap
, &sh
->dev
[sh
->pd_idx
].flags
);
4528 spin_lock_irq(&sh
->stripe_lock
);
4529 for (d
= 0; d
< conf
->raid_disks
; d
++) {
4530 if (d
== sh
->pd_idx
|| d
== sh
->qd_idx
)
4532 if (sh
->dev
[d
].towrite
|| sh
->dev
[d
].toread
) {
4533 set_bit(R5_Overlap
, &sh
->dev
[d
].flags
);
4534 spin_unlock_irq(&sh
->stripe_lock
);
4540 set_bit(STRIPE_DISCARD
, &sh
->state
);
4541 finish_wait(&conf
->wait_for_overlap
, &w
);
4542 for (d
= 0; d
< conf
->raid_disks
; d
++) {
4543 if (d
== sh
->pd_idx
|| d
== sh
->qd_idx
)
4545 sh
->dev
[d
].towrite
= bi
;
4546 set_bit(R5_OVERWRITE
, &sh
->dev
[d
].flags
);
4547 raid5_inc_bi_active_stripes(bi
);
4549 spin_unlock_irq(&sh
->stripe_lock
);
4550 if (conf
->mddev
->bitmap
) {
4552 d
< conf
->raid_disks
- conf
->max_degraded
;
4554 bitmap_startwrite(mddev
->bitmap
,
4558 sh
->bm_seq
= conf
->seq_flush
+ 1;
4559 set_bit(STRIPE_BIT_DELAY
, &sh
->state
);
4562 set_bit(STRIPE_HANDLE
, &sh
->state
);
4563 clear_bit(STRIPE_DELAYED
, &sh
->state
);
4564 if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
4565 atomic_inc(&conf
->preread_active_stripes
);
4566 release_stripe_plug(mddev
, sh
);
4569 remaining
= raid5_dec_bi_active_stripes(bi
);
4570 if (remaining
== 0) {
4571 md_write_end(mddev
);
4576 static void make_request(struct mddev
*mddev
, struct bio
* bi
)
4578 struct r5conf
*conf
= mddev
->private;
4580 sector_t new_sector
;
4581 sector_t logical_sector
, last_sector
;
4582 struct stripe_head
*sh
;
4583 const int rw
= bio_data_dir(bi
);
4588 if (unlikely(bi
->bi_rw
& REQ_FLUSH
)) {
4589 md_flush_request(mddev
, bi
);
4593 md_write_start(mddev
, bi
);
4596 mddev
->reshape_position
== MaxSector
&&
4597 chunk_aligned_read(mddev
,bi
))
4600 if (unlikely(bi
->bi_rw
& REQ_DISCARD
)) {
4601 make_discard_request(mddev
, bi
);
4605 logical_sector
= bi
->bi_iter
.bi_sector
& ~((sector_t
)STRIPE_SECTORS
-1);
4606 last_sector
= bio_end_sector(bi
);
4608 bi
->bi_phys_segments
= 1; /* over-loaded to count active stripes */
4610 prepare_to_wait(&conf
->wait_for_overlap
, &w
, TASK_UNINTERRUPTIBLE
);
4611 for (;logical_sector
< last_sector
; logical_sector
+= STRIPE_SECTORS
) {
4617 seq
= read_seqcount_begin(&conf
->gen_lock
);
4620 prepare_to_wait(&conf
->wait_for_overlap
, &w
,
4621 TASK_UNINTERRUPTIBLE
);
4622 if (unlikely(conf
->reshape_progress
!= MaxSector
)) {
4623 /* spinlock is needed as reshape_progress may be
4624 * 64bit on a 32bit platform, and so it might be
4625 * possible to see a half-updated value
4626 * Of course reshape_progress could change after
4627 * the lock is dropped, so once we get a reference
4628 * to the stripe that we think it is, we will have
4631 spin_lock_irq(&conf
->device_lock
);
4632 if (mddev
->reshape_backwards
4633 ? logical_sector
< conf
->reshape_progress
4634 : logical_sector
>= conf
->reshape_progress
) {
4637 if (mddev
->reshape_backwards
4638 ? logical_sector
< conf
->reshape_safe
4639 : logical_sector
>= conf
->reshape_safe
) {
4640 spin_unlock_irq(&conf
->device_lock
);
4646 spin_unlock_irq(&conf
->device_lock
);
4649 new_sector
= raid5_compute_sector(conf
, logical_sector
,
4652 pr_debug("raid456: make_request, sector %llu logical %llu\n",
4653 (unsigned long long)new_sector
,
4654 (unsigned long long)logical_sector
);
4656 sh
= get_active_stripe(conf
, new_sector
, previous
,
4657 (bi
->bi_rw
&RWA_MASK
), 0);
4659 if (unlikely(previous
)) {
4660 /* expansion might have moved on while waiting for a
4661 * stripe, so we must do the range check again.
4662 * Expansion could still move past after this
4663 * test, but as we are holding a reference to
4664 * 'sh', we know that if that happens,
4665 * STRIPE_EXPANDING will get set and the expansion
4666 * won't proceed until we finish with the stripe.
4669 spin_lock_irq(&conf
->device_lock
);
4670 if (mddev
->reshape_backwards
4671 ? logical_sector
>= conf
->reshape_progress
4672 : logical_sector
< conf
->reshape_progress
)
4673 /* mismatch, need to try again */
4675 spin_unlock_irq(&conf
->device_lock
);
4683 if (read_seqcount_retry(&conf
->gen_lock
, seq
)) {
4684 /* Might have got the wrong stripe_head
4692 logical_sector
>= mddev
->suspend_lo
&&
4693 logical_sector
< mddev
->suspend_hi
) {
4695 /* As the suspend_* range is controlled by
4696 * userspace, we want an interruptible
4699 flush_signals(current
);
4700 prepare_to_wait(&conf
->wait_for_overlap
,
4701 &w
, TASK_INTERRUPTIBLE
);
4702 if (logical_sector
>= mddev
->suspend_lo
&&
4703 logical_sector
< mddev
->suspend_hi
) {
4710 if (test_bit(STRIPE_EXPANDING
, &sh
->state
) ||
4711 !add_stripe_bio(sh
, bi
, dd_idx
, rw
)) {
4712 /* Stripe is busy expanding or
4713 * add failed due to overlap. Flush everything
4716 md_wakeup_thread(mddev
->thread
);
4722 set_bit(STRIPE_HANDLE
, &sh
->state
);
4723 clear_bit(STRIPE_DELAYED
, &sh
->state
);
4724 if ((bi
->bi_rw
& REQ_SYNC
) &&
4725 !test_and_set_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
4726 atomic_inc(&conf
->preread_active_stripes
);
4727 release_stripe_plug(mddev
, sh
);
4729 /* cannot get stripe for read-ahead, just give-up */
4730 clear_bit(BIO_UPTODATE
, &bi
->bi_flags
);
4734 finish_wait(&conf
->wait_for_overlap
, &w
);
4736 remaining
= raid5_dec_bi_active_stripes(bi
);
4737 if (remaining
== 0) {
4740 md_write_end(mddev
);
4742 trace_block_bio_complete(bdev_get_queue(bi
->bi_bdev
),
4748 static sector_t
raid5_size(struct mddev
*mddev
, sector_t sectors
, int raid_disks
);
4750 static sector_t
reshape_request(struct mddev
*mddev
, sector_t sector_nr
, int *skipped
)
4752 /* reshaping is quite different to recovery/resync so it is
4753 * handled quite separately ... here.
4755 * On each call to sync_request, we gather one chunk worth of
4756 * destination stripes and flag them as expanding.
4757 * Then we find all the source stripes and request reads.
4758 * As the reads complete, handle_stripe will copy the data
4759 * into the destination stripe and release that stripe.
4761 struct r5conf
*conf
= mddev
->private;
4762 struct stripe_head
*sh
;
4763 sector_t first_sector
, last_sector
;
4764 int raid_disks
= conf
->previous_raid_disks
;
4765 int data_disks
= raid_disks
- conf
->max_degraded
;
4766 int new_data_disks
= conf
->raid_disks
- conf
->max_degraded
;
4769 sector_t writepos
, readpos
, safepos
;
4770 sector_t stripe_addr
;
4771 int reshape_sectors
;
4772 struct list_head stripes
;
4774 if (sector_nr
== 0) {
4775 /* If restarting in the middle, skip the initial sectors */
4776 if (mddev
->reshape_backwards
&&
4777 conf
->reshape_progress
< raid5_size(mddev
, 0, 0)) {
4778 sector_nr
= raid5_size(mddev
, 0, 0)
4779 - conf
->reshape_progress
;
4780 } else if (!mddev
->reshape_backwards
&&
4781 conf
->reshape_progress
> 0)
4782 sector_nr
= conf
->reshape_progress
;
4783 sector_div(sector_nr
, new_data_disks
);
4785 mddev
->curr_resync_completed
= sector_nr
;
4786 sysfs_notify(&mddev
->kobj
, NULL
, "sync_completed");
4792 /* We need to process a full chunk at a time.
4793 * If old and new chunk sizes differ, we need to process the
4796 if (mddev
->new_chunk_sectors
> mddev
->chunk_sectors
)
4797 reshape_sectors
= mddev
->new_chunk_sectors
;
4799 reshape_sectors
= mddev
->chunk_sectors
;
4801 /* We update the metadata at least every 10 seconds, or when
4802 * the data about to be copied would over-write the source of
4803 * the data at the front of the range. i.e. one new_stripe
4804 * along from reshape_progress new_maps to after where
4805 * reshape_safe old_maps to
4807 writepos
= conf
->reshape_progress
;
4808 sector_div(writepos
, new_data_disks
);
4809 readpos
= conf
->reshape_progress
;
4810 sector_div(readpos
, data_disks
);
4811 safepos
= conf
->reshape_safe
;
4812 sector_div(safepos
, data_disks
);
4813 if (mddev
->reshape_backwards
) {
4814 writepos
-= min_t(sector_t
, reshape_sectors
, writepos
);
4815 readpos
+= reshape_sectors
;
4816 safepos
+= reshape_sectors
;
4818 writepos
+= reshape_sectors
;
4819 readpos
-= min_t(sector_t
, reshape_sectors
, readpos
);
4820 safepos
-= min_t(sector_t
, reshape_sectors
, safepos
);
4823 /* Having calculated the 'writepos' possibly use it
4824 * to set 'stripe_addr' which is where we will write to.
4826 if (mddev
->reshape_backwards
) {
4827 BUG_ON(conf
->reshape_progress
== 0);
4828 stripe_addr
= writepos
;
4829 BUG_ON((mddev
->dev_sectors
&
4830 ~((sector_t
)reshape_sectors
- 1))
4831 - reshape_sectors
- stripe_addr
4834 BUG_ON(writepos
!= sector_nr
+ reshape_sectors
);
4835 stripe_addr
= sector_nr
;
4838 /* 'writepos' is the most advanced device address we might write.
4839 * 'readpos' is the least advanced device address we might read.
4840 * 'safepos' is the least address recorded in the metadata as having
4842 * If there is a min_offset_diff, these are adjusted either by
4843 * increasing the safepos/readpos if diff is negative, or
4844 * increasing writepos if diff is positive.
4845 * If 'readpos' is then behind 'writepos', there is no way that we can
4846 * ensure safety in the face of a crash - that must be done by userspace
4847 * making a backup of the data. So in that case there is no particular
4848 * rush to update metadata.
4849 * Otherwise if 'safepos' is behind 'writepos', then we really need to
4850 * update the metadata to advance 'safepos' to match 'readpos' so that
4851 * we can be safe in the event of a crash.
4852 * So we insist on updating metadata if safepos is behind writepos and
4853 * readpos is beyond writepos.
4854 * In any case, update the metadata every 10 seconds.
4855 * Maybe that number should be configurable, but I'm not sure it is
4856 * worth it.... maybe it could be a multiple of safemode_delay???
4858 if (conf
->min_offset_diff
< 0) {
4859 safepos
+= -conf
->min_offset_diff
;
4860 readpos
+= -conf
->min_offset_diff
;
4862 writepos
+= conf
->min_offset_diff
;
4864 if ((mddev
->reshape_backwards
4865 ? (safepos
> writepos
&& readpos
< writepos
)
4866 : (safepos
< writepos
&& readpos
> writepos
)) ||
4867 time_after(jiffies
, conf
->reshape_checkpoint
+ 10*HZ
)) {
4868 /* Cannot proceed until we've updated the superblock... */
4869 wait_event(conf
->wait_for_overlap
,
4870 atomic_read(&conf
->reshape_stripes
)==0
4871 || test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
));
4872 if (atomic_read(&conf
->reshape_stripes
) != 0)
4874 mddev
->reshape_position
= conf
->reshape_progress
;
4875 mddev
->curr_resync_completed
= sector_nr
;
4876 conf
->reshape_checkpoint
= jiffies
;
4877 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
4878 md_wakeup_thread(mddev
->thread
);
4879 wait_event(mddev
->sb_wait
, mddev
->flags
== 0 ||
4880 test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
));
4881 if (test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
))
4883 spin_lock_irq(&conf
->device_lock
);
4884 conf
->reshape_safe
= mddev
->reshape_position
;
4885 spin_unlock_irq(&conf
->device_lock
);
4886 wake_up(&conf
->wait_for_overlap
);
4887 sysfs_notify(&mddev
->kobj
, NULL
, "sync_completed");
4890 INIT_LIST_HEAD(&stripes
);
4891 for (i
= 0; i
< reshape_sectors
; i
+= STRIPE_SECTORS
) {
4893 int skipped_disk
= 0;
4894 sh
= get_active_stripe(conf
, stripe_addr
+i
, 0, 0, 1);
4895 set_bit(STRIPE_EXPANDING
, &sh
->state
);
4896 atomic_inc(&conf
->reshape_stripes
);
4897 /* If any of this stripe is beyond the end of the old
4898 * array, then we need to zero those blocks
4900 for (j
=sh
->disks
; j
--;) {
4902 if (j
== sh
->pd_idx
)
4904 if (conf
->level
== 6 &&
4907 s
= compute_blocknr(sh
, j
, 0);
4908 if (s
< raid5_size(mddev
, 0, 0)) {
4912 memset(page_address(sh
->dev
[j
].page
), 0, STRIPE_SIZE
);
4913 set_bit(R5_Expanded
, &sh
->dev
[j
].flags
);
4914 set_bit(R5_UPTODATE
, &sh
->dev
[j
].flags
);
4916 if (!skipped_disk
) {
4917 set_bit(STRIPE_EXPAND_READY
, &sh
->state
);
4918 set_bit(STRIPE_HANDLE
, &sh
->state
);
4920 list_add(&sh
->lru
, &stripes
);
4922 spin_lock_irq(&conf
->device_lock
);
4923 if (mddev
->reshape_backwards
)
4924 conf
->reshape_progress
-= reshape_sectors
* new_data_disks
;
4926 conf
->reshape_progress
+= reshape_sectors
* new_data_disks
;
4927 spin_unlock_irq(&conf
->device_lock
);
4928 /* Ok, those stripe are ready. We can start scheduling
4929 * reads on the source stripes.
4930 * The source stripes are determined by mapping the first and last
4931 * block on the destination stripes.
4934 raid5_compute_sector(conf
, stripe_addr
*(new_data_disks
),
4937 raid5_compute_sector(conf
, ((stripe_addr
+reshape_sectors
)
4938 * new_data_disks
- 1),
4940 if (last_sector
>= mddev
->dev_sectors
)
4941 last_sector
= mddev
->dev_sectors
- 1;
4942 while (first_sector
<= last_sector
) {
4943 sh
= get_active_stripe(conf
, first_sector
, 1, 0, 1);
4944 set_bit(STRIPE_EXPAND_SOURCE
, &sh
->state
);
4945 set_bit(STRIPE_HANDLE
, &sh
->state
);
4947 first_sector
+= STRIPE_SECTORS
;
4949 /* Now that the sources are clearly marked, we can release
4950 * the destination stripes
4952 while (!list_empty(&stripes
)) {
4953 sh
= list_entry(stripes
.next
, struct stripe_head
, lru
);
4954 list_del_init(&sh
->lru
);
4957 /* If this takes us to the resync_max point where we have to pause,
4958 * then we need to write out the superblock.
4960 sector_nr
+= reshape_sectors
;
4961 if ((sector_nr
- mddev
->curr_resync_completed
) * 2
4962 >= mddev
->resync_max
- mddev
->curr_resync_completed
) {
4963 /* Cannot proceed until we've updated the superblock... */
4964 wait_event(conf
->wait_for_overlap
,
4965 atomic_read(&conf
->reshape_stripes
) == 0
4966 || test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
));
4967 if (atomic_read(&conf
->reshape_stripes
) != 0)
4969 mddev
->reshape_position
= conf
->reshape_progress
;
4970 mddev
->curr_resync_completed
= sector_nr
;
4971 conf
->reshape_checkpoint
= jiffies
;
4972 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
4973 md_wakeup_thread(mddev
->thread
);
4974 wait_event(mddev
->sb_wait
,
4975 !test_bit(MD_CHANGE_DEVS
, &mddev
->flags
)
4976 || test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
));
4977 if (test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
))
4979 spin_lock_irq(&conf
->device_lock
);
4980 conf
->reshape_safe
= mddev
->reshape_position
;
4981 spin_unlock_irq(&conf
->device_lock
);
4982 wake_up(&conf
->wait_for_overlap
);
4983 sysfs_notify(&mddev
->kobj
, NULL
, "sync_completed");
4986 return reshape_sectors
;
4989 /* FIXME go_faster isn't used */
4990 static inline sector_t
sync_request(struct mddev
*mddev
, sector_t sector_nr
, int *skipped
, int go_faster
)
4992 struct r5conf
*conf
= mddev
->private;
4993 struct stripe_head
*sh
;
4994 sector_t max_sector
= mddev
->dev_sectors
;
4995 sector_t sync_blocks
;
4996 int still_degraded
= 0;
4999 if (sector_nr
>= max_sector
) {
5000 /* just being told to finish up .. nothing much to do */
5002 if (test_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
)) {
5007 if (mddev
->curr_resync
< max_sector
) /* aborted */
5008 bitmap_end_sync(mddev
->bitmap
, mddev
->curr_resync
,
5010 else /* completed sync */
5012 bitmap_close_sync(mddev
->bitmap
);
5017 /* Allow raid5_quiesce to complete */
5018 wait_event(conf
->wait_for_overlap
, conf
->quiesce
!= 2);
5020 if (test_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
))
5021 return reshape_request(mddev
, sector_nr
, skipped
);
5023 /* No need to check resync_max as we never do more than one
5024 * stripe, and as resync_max will always be on a chunk boundary,
5025 * if the check in md_do_sync didn't fire, there is no chance
5026 * of overstepping resync_max here
5029 /* if there is too many failed drives and we are trying
5030 * to resync, then assert that we are finished, because there is
5031 * nothing we can do.
5033 if (mddev
->degraded
>= conf
->max_degraded
&&
5034 test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
)) {
5035 sector_t rv
= mddev
->dev_sectors
- sector_nr
;
5039 if (!test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
) &&
5041 !bitmap_start_sync(mddev
->bitmap
, sector_nr
, &sync_blocks
, 1) &&
5042 sync_blocks
>= STRIPE_SECTORS
) {
5043 /* we can skip this block, and probably more */
5044 sync_blocks
/= STRIPE_SECTORS
;
5046 return sync_blocks
* STRIPE_SECTORS
; /* keep things rounded to whole stripes */
5049 bitmap_cond_end_sync(mddev
->bitmap
, sector_nr
);
5051 sh
= get_active_stripe(conf
, sector_nr
, 0, 1, 0);
5053 sh
= get_active_stripe(conf
, sector_nr
, 0, 0, 0);
5054 /* make sure we don't swamp the stripe cache if someone else
5055 * is trying to get access
5057 schedule_timeout_uninterruptible(1);
5059 /* Need to check if array will still be degraded after recovery/resync
5060 * We don't need to check the 'failed' flag as when that gets set,
5063 for (i
= 0; i
< conf
->raid_disks
; i
++)
5064 if (conf
->disks
[i
].rdev
== NULL
)
5067 bitmap_start_sync(mddev
->bitmap
, sector_nr
, &sync_blocks
, still_degraded
);
5069 set_bit(STRIPE_SYNC_REQUESTED
, &sh
->state
);
5070 set_bit(STRIPE_HANDLE
, &sh
->state
);
5074 return STRIPE_SECTORS
;
5077 static int retry_aligned_read(struct r5conf
*conf
, struct bio
*raid_bio
)
5079 /* We may not be able to submit a whole bio at once as there
5080 * may not be enough stripe_heads available.
5081 * We cannot pre-allocate enough stripe_heads as we may need
5082 * more than exist in the cache (if we allow ever large chunks).
5083 * So we do one stripe head at a time and record in
5084 * ->bi_hw_segments how many have been done.
5086 * We *know* that this entire raid_bio is in one chunk, so
5087 * it will be only one 'dd_idx' and only need one call to raid5_compute_sector.
5089 struct stripe_head
*sh
;
5091 sector_t sector
, logical_sector
, last_sector
;
5096 logical_sector
= raid_bio
->bi_iter
.bi_sector
&
5097 ~((sector_t
)STRIPE_SECTORS
-1);
5098 sector
= raid5_compute_sector(conf
, logical_sector
,
5100 last_sector
= bio_end_sector(raid_bio
);
5102 for (; logical_sector
< last_sector
;
5103 logical_sector
+= STRIPE_SECTORS
,
5104 sector
+= STRIPE_SECTORS
,
5107 if (scnt
< raid5_bi_processed_stripes(raid_bio
))
5108 /* already done this stripe */
5111 sh
= get_active_stripe(conf
, sector
, 0, 1, 1);
5114 /* failed to get a stripe - must wait */
5115 raid5_set_bi_processed_stripes(raid_bio
, scnt
);
5116 conf
->retry_read_aligned
= raid_bio
;
5120 if (!add_stripe_bio(sh
, raid_bio
, dd_idx
, 0)) {
5122 raid5_set_bi_processed_stripes(raid_bio
, scnt
);
5123 conf
->retry_read_aligned
= raid_bio
;
5127 set_bit(R5_ReadNoMerge
, &sh
->dev
[dd_idx
].flags
);
5132 remaining
= raid5_dec_bi_active_stripes(raid_bio
);
5133 if (remaining
== 0) {
5134 trace_block_bio_complete(bdev_get_queue(raid_bio
->bi_bdev
),
5136 bio_endio(raid_bio
, 0);
5138 if (atomic_dec_and_test(&conf
->active_aligned_reads
))
5139 wake_up(&conf
->wait_for_stripe
);
5143 static int handle_active_stripes(struct r5conf
*conf
, int group
,
5144 struct r5worker
*worker
,
5145 struct list_head
*temp_inactive_list
)
5147 struct stripe_head
*batch
[MAX_STRIPE_BATCH
], *sh
;
5148 int i
, batch_size
= 0, hash
;
5149 bool release_inactive
= false;
5151 while (batch_size
< MAX_STRIPE_BATCH
&&
5152 (sh
= __get_priority_stripe(conf
, group
)) != NULL
)
5153 batch
[batch_size
++] = sh
;
5155 if (batch_size
== 0) {
5156 for (i
= 0; i
< NR_STRIPE_HASH_LOCKS
; i
++)
5157 if (!list_empty(temp_inactive_list
+ i
))
5159 if (i
== NR_STRIPE_HASH_LOCKS
)
5161 release_inactive
= true;
5163 spin_unlock_irq(&conf
->device_lock
);
5165 release_inactive_stripe_list(conf
, temp_inactive_list
,
5166 NR_STRIPE_HASH_LOCKS
);
5168 if (release_inactive
) {
5169 spin_lock_irq(&conf
->device_lock
);
5173 for (i
= 0; i
< batch_size
; i
++)
5174 handle_stripe(batch
[i
]);
5178 spin_lock_irq(&conf
->device_lock
);
5179 for (i
= 0; i
< batch_size
; i
++) {
5180 hash
= batch
[i
]->hash_lock_index
;
5181 __release_stripe(conf
, batch
[i
], &temp_inactive_list
[hash
]);
5186 static void raid5_do_work(struct work_struct
*work
)
5188 struct r5worker
*worker
= container_of(work
, struct r5worker
, work
);
5189 struct r5worker_group
*group
= worker
->group
;
5190 struct r5conf
*conf
= group
->conf
;
5191 int group_id
= group
- conf
->worker_groups
;
5193 struct blk_plug plug
;
5195 pr_debug("+++ raid5worker active\n");
5197 blk_start_plug(&plug
);
5199 spin_lock_irq(&conf
->device_lock
);
5201 int batch_size
, released
;
5203 released
= release_stripe_list(conf
, worker
->temp_inactive_list
);
5205 batch_size
= handle_active_stripes(conf
, group_id
, worker
,
5206 worker
->temp_inactive_list
);
5207 worker
->working
= false;
5208 if (!batch_size
&& !released
)
5210 handled
+= batch_size
;
5212 pr_debug("%d stripes handled\n", handled
);
5214 spin_unlock_irq(&conf
->device_lock
);
5215 blk_finish_plug(&plug
);
5217 pr_debug("--- raid5worker inactive\n");
5221 * This is our raid5 kernel thread.
5223 * We scan the hash table for stripes which can be handled now.
5224 * During the scan, completed stripes are saved for us by the interrupt
5225 * handler, so that they will not have to wait for our next wakeup.
5227 static void raid5d(struct md_thread
*thread
)
5229 struct mddev
*mddev
= thread
->mddev
;
5230 struct r5conf
*conf
= mddev
->private;
5232 struct blk_plug plug
;
5234 pr_debug("+++ raid5d active\n");
5236 md_check_recovery(mddev
);
5238 blk_start_plug(&plug
);
5240 spin_lock_irq(&conf
->device_lock
);
5243 int batch_size
, released
;
5245 released
= release_stripe_list(conf
, conf
->temp_inactive_list
);
5248 !list_empty(&conf
->bitmap_list
)) {
5249 /* Now is a good time to flush some bitmap updates */
5251 spin_unlock_irq(&conf
->device_lock
);
5252 bitmap_unplug(mddev
->bitmap
);
5253 spin_lock_irq(&conf
->device_lock
);
5254 conf
->seq_write
= conf
->seq_flush
;
5255 activate_bit_delay(conf
, conf
->temp_inactive_list
);
5257 raid5_activate_delayed(conf
);
5259 while ((bio
= remove_bio_from_retry(conf
))) {
5261 spin_unlock_irq(&conf
->device_lock
);
5262 ok
= retry_aligned_read(conf
, bio
);
5263 spin_lock_irq(&conf
->device_lock
);
5269 batch_size
= handle_active_stripes(conf
, ANY_GROUP
, NULL
,
5270 conf
->temp_inactive_list
);
5271 if (!batch_size
&& !released
)
5273 handled
+= batch_size
;
5275 if (mddev
->flags
& ~(1<<MD_CHANGE_PENDING
)) {
5276 spin_unlock_irq(&conf
->device_lock
);
5277 md_check_recovery(mddev
);
5278 spin_lock_irq(&conf
->device_lock
);
5281 pr_debug("%d stripes handled\n", handled
);
5283 spin_unlock_irq(&conf
->device_lock
);
5285 async_tx_issue_pending_all();
5286 blk_finish_plug(&plug
);
5288 pr_debug("--- raid5d inactive\n");
5292 raid5_show_stripe_cache_size(struct mddev
*mddev
, char *page
)
5294 struct r5conf
*conf
= mddev
->private;
5296 return sprintf(page
, "%d\n", conf
->max_nr_stripes
);
5302 raid5_set_cache_size(struct mddev
*mddev
, int size
)
5304 struct r5conf
*conf
= mddev
->private;
5308 if (size
<= 16 || size
> 32768)
5310 hash
= (conf
->max_nr_stripes
- 1) % NR_STRIPE_HASH_LOCKS
;
5311 while (size
< conf
->max_nr_stripes
) {
5312 if (drop_one_stripe(conf
, hash
))
5313 conf
->max_nr_stripes
--;
5318 hash
= NR_STRIPE_HASH_LOCKS
- 1;
5320 err
= md_allow_write(mddev
);
5323 hash
= conf
->max_nr_stripes
% NR_STRIPE_HASH_LOCKS
;
5324 while (size
> conf
->max_nr_stripes
) {
5325 if (grow_one_stripe(conf
, hash
))
5326 conf
->max_nr_stripes
++;
5328 hash
= (hash
+ 1) % NR_STRIPE_HASH_LOCKS
;
5332 EXPORT_SYMBOL(raid5_set_cache_size
);
5335 raid5_store_stripe_cache_size(struct mddev
*mddev
, const char *page
, size_t len
)
5337 struct r5conf
*conf
= mddev
->private;
5341 if (len
>= PAGE_SIZE
)
5346 if (kstrtoul(page
, 10, &new))
5348 err
= raid5_set_cache_size(mddev
, new);
5354 static struct md_sysfs_entry
5355 raid5_stripecache_size
= __ATTR(stripe_cache_size
, S_IRUGO
| S_IWUSR
,
5356 raid5_show_stripe_cache_size
,
5357 raid5_store_stripe_cache_size
);
5360 raid5_show_preread_threshold(struct mddev
*mddev
, char *page
)
5362 struct r5conf
*conf
= mddev
->private;
5364 return sprintf(page
, "%d\n", conf
->bypass_threshold
);
5370 raid5_store_preread_threshold(struct mddev
*mddev
, const char *page
, size_t len
)
5372 struct r5conf
*conf
= mddev
->private;
5374 if (len
>= PAGE_SIZE
)
5379 if (kstrtoul(page
, 10, &new))
5381 if (new > conf
->max_nr_stripes
)
5383 conf
->bypass_threshold
= new;
5387 static struct md_sysfs_entry
5388 raid5_preread_bypass_threshold
= __ATTR(preread_bypass_threshold
,
5390 raid5_show_preread_threshold
,
5391 raid5_store_preread_threshold
);
5394 raid5_show_skip_copy(struct mddev
*mddev
, char *page
)
5396 struct r5conf
*conf
= mddev
->private;
5398 return sprintf(page
, "%d\n", conf
->skip_copy
);
5404 raid5_store_skip_copy(struct mddev
*mddev
, const char *page
, size_t len
)
5406 struct r5conf
*conf
= mddev
->private;
5408 if (len
>= PAGE_SIZE
)
5413 if (kstrtoul(page
, 10, &new))
5416 if (new == conf
->skip_copy
)
5419 mddev_suspend(mddev
);
5420 conf
->skip_copy
= new;
5422 mddev
->queue
->backing_dev_info
.capabilities
|=
5423 BDI_CAP_STABLE_WRITES
;
5425 mddev
->queue
->backing_dev_info
.capabilities
&=
5426 ~BDI_CAP_STABLE_WRITES
;
5427 mddev_resume(mddev
);
5431 static struct md_sysfs_entry
5432 raid5_skip_copy
= __ATTR(skip_copy
, S_IRUGO
| S_IWUSR
,
5433 raid5_show_skip_copy
,
5434 raid5_store_skip_copy
);
5437 stripe_cache_active_show(struct mddev
*mddev
, char *page
)
5439 struct r5conf
*conf
= mddev
->private;
5441 return sprintf(page
, "%d\n", atomic_read(&conf
->active_stripes
));
5446 static struct md_sysfs_entry
5447 raid5_stripecache_active
= __ATTR_RO(stripe_cache_active
);
5450 raid5_show_group_thread_cnt(struct mddev
*mddev
, char *page
)
5452 struct r5conf
*conf
= mddev
->private;
5454 return sprintf(page
, "%d\n", conf
->worker_cnt_per_group
);
5459 static int alloc_thread_groups(struct r5conf
*conf
, int cnt
,
5461 int *worker_cnt_per_group
,
5462 struct r5worker_group
**worker_groups
);
5464 raid5_store_group_thread_cnt(struct mddev
*mddev
, const char *page
, size_t len
)
5466 struct r5conf
*conf
= mddev
->private;
5469 struct r5worker_group
*new_groups
, *old_groups
;
5470 int group_cnt
, worker_cnt_per_group
;
5472 if (len
>= PAGE_SIZE
)
5477 if (kstrtoul(page
, 10, &new))
5480 if (new == conf
->worker_cnt_per_group
)
5483 mddev_suspend(mddev
);
5485 old_groups
= conf
->worker_groups
;
5487 flush_workqueue(raid5_wq
);
5489 err
= alloc_thread_groups(conf
, new,
5490 &group_cnt
, &worker_cnt_per_group
,
5493 spin_lock_irq(&conf
->device_lock
);
5494 conf
->group_cnt
= group_cnt
;
5495 conf
->worker_cnt_per_group
= worker_cnt_per_group
;
5496 conf
->worker_groups
= new_groups
;
5497 spin_unlock_irq(&conf
->device_lock
);
5500 kfree(old_groups
[0].workers
);
5504 mddev_resume(mddev
);
5511 static struct md_sysfs_entry
5512 raid5_group_thread_cnt
= __ATTR(group_thread_cnt
, S_IRUGO
| S_IWUSR
,
5513 raid5_show_group_thread_cnt
,
5514 raid5_store_group_thread_cnt
);
5516 static struct attribute
*raid5_attrs
[] = {
5517 &raid5_stripecache_size
.attr
,
5518 &raid5_stripecache_active
.attr
,
5519 &raid5_preread_bypass_threshold
.attr
,
5520 &raid5_group_thread_cnt
.attr
,
5521 &raid5_skip_copy
.attr
,
5524 static struct attribute_group raid5_attrs_group
= {
5526 .attrs
= raid5_attrs
,
5529 static int alloc_thread_groups(struct r5conf
*conf
, int cnt
,
5531 int *worker_cnt_per_group
,
5532 struct r5worker_group
**worker_groups
)
5536 struct r5worker
*workers
;
5538 *worker_cnt_per_group
= cnt
;
5541 *worker_groups
= NULL
;
5544 *group_cnt
= num_possible_nodes();
5545 size
= sizeof(struct r5worker
) * cnt
;
5546 workers
= kzalloc(size
* *group_cnt
, GFP_NOIO
);
5547 *worker_groups
= kzalloc(sizeof(struct r5worker_group
) *
5548 *group_cnt
, GFP_NOIO
);
5549 if (!*worker_groups
|| !workers
) {
5551 kfree(*worker_groups
);
5555 for (i
= 0; i
< *group_cnt
; i
++) {
5556 struct r5worker_group
*group
;
5558 group
= &(*worker_groups
)[i
];
5559 INIT_LIST_HEAD(&group
->handle_list
);
5561 group
->workers
= workers
+ i
* cnt
;
5563 for (j
= 0; j
< cnt
; j
++) {
5564 struct r5worker
*worker
= group
->workers
+ j
;
5565 worker
->group
= group
;
5566 INIT_WORK(&worker
->work
, raid5_do_work
);
5568 for (k
= 0; k
< NR_STRIPE_HASH_LOCKS
; k
++)
5569 INIT_LIST_HEAD(worker
->temp_inactive_list
+ k
);
5576 static void free_thread_groups(struct r5conf
*conf
)
5578 if (conf
->worker_groups
)
5579 kfree(conf
->worker_groups
[0].workers
);
5580 kfree(conf
->worker_groups
);
5581 conf
->worker_groups
= NULL
;
5585 raid5_size(struct mddev
*mddev
, sector_t sectors
, int raid_disks
)
5587 struct r5conf
*conf
= mddev
->private;
5590 sectors
= mddev
->dev_sectors
;
5592 /* size is defined by the smallest of previous and new size */
5593 raid_disks
= min(conf
->raid_disks
, conf
->previous_raid_disks
);
5595 sectors
&= ~((sector_t
)mddev
->chunk_sectors
- 1);
5596 sectors
&= ~((sector_t
)mddev
->new_chunk_sectors
- 1);
5597 return sectors
* (raid_disks
- conf
->max_degraded
);
5600 static void free_scratch_buffer(struct r5conf
*conf
, struct raid5_percpu
*percpu
)
5602 safe_put_page(percpu
->spare_page
);
5603 kfree(percpu
->scribble
);
5604 percpu
->spare_page
= NULL
;
5605 percpu
->scribble
= NULL
;
5608 static int alloc_scratch_buffer(struct r5conf
*conf
, struct raid5_percpu
*percpu
)
5610 if (conf
->level
== 6 && !percpu
->spare_page
)
5611 percpu
->spare_page
= alloc_page(GFP_KERNEL
);
5612 if (!percpu
->scribble
)
5613 percpu
->scribble
= kmalloc(conf
->scribble_len
, GFP_KERNEL
);
5615 if (!percpu
->scribble
|| (conf
->level
== 6 && !percpu
->spare_page
)) {
5616 free_scratch_buffer(conf
, percpu
);
5623 static void raid5_free_percpu(struct r5conf
*conf
)
5630 #ifdef CONFIG_HOTPLUG_CPU
5631 unregister_cpu_notifier(&conf
->cpu_notify
);
5635 for_each_possible_cpu(cpu
)
5636 free_scratch_buffer(conf
, per_cpu_ptr(conf
->percpu
, cpu
));
5639 free_percpu(conf
->percpu
);
5642 static void free_conf(struct r5conf
*conf
)
5644 free_thread_groups(conf
);
5645 shrink_stripes(conf
);
5646 raid5_free_percpu(conf
);
5648 kfree(conf
->stripe_hashtbl
);
5652 #ifdef CONFIG_HOTPLUG_CPU
5653 static int raid456_cpu_notify(struct notifier_block
*nfb
, unsigned long action
,
5656 struct r5conf
*conf
= container_of(nfb
, struct r5conf
, cpu_notify
);
5657 long cpu
= (long)hcpu
;
5658 struct raid5_percpu
*percpu
= per_cpu_ptr(conf
->percpu
, cpu
);
5661 case CPU_UP_PREPARE
:
5662 case CPU_UP_PREPARE_FROZEN
:
5663 if (alloc_scratch_buffer(conf
, percpu
)) {
5664 pr_err("%s: failed memory allocation for cpu%ld\n",
5666 return notifier_from_errno(-ENOMEM
);
5670 case CPU_DEAD_FROZEN
:
5671 free_scratch_buffer(conf
, per_cpu_ptr(conf
->percpu
, cpu
));
5680 static int raid5_alloc_percpu(struct r5conf
*conf
)
5685 conf
->percpu
= alloc_percpu(struct raid5_percpu
);
5689 #ifdef CONFIG_HOTPLUG_CPU
5690 conf
->cpu_notify
.notifier_call
= raid456_cpu_notify
;
5691 conf
->cpu_notify
.priority
= 0;
5692 err
= register_cpu_notifier(&conf
->cpu_notify
);
5698 for_each_present_cpu(cpu
) {
5699 err
= alloc_scratch_buffer(conf
, per_cpu_ptr(conf
->percpu
, cpu
));
5701 pr_err("%s: failed memory allocation for cpu%ld\n",
5711 static struct r5conf
*setup_conf(struct mddev
*mddev
)
5713 struct r5conf
*conf
;
5714 int raid_disk
, memory
, max_disks
;
5715 struct md_rdev
*rdev
;
5716 struct disk_info
*disk
;
5719 int group_cnt
, worker_cnt_per_group
;
5720 struct r5worker_group
*new_group
;
5722 if (mddev
->new_level
!= 5
5723 && mddev
->new_level
!= 4
5724 && mddev
->new_level
!= 6) {
5725 printk(KERN_ERR
"md/raid:%s: raid level not set to 4/5/6 (%d)\n",
5726 mdname(mddev
), mddev
->new_level
);
5727 return ERR_PTR(-EIO
);
5729 if ((mddev
->new_level
== 5
5730 && !algorithm_valid_raid5(mddev
->new_layout
)) ||
5731 (mddev
->new_level
== 6
5732 && !algorithm_valid_raid6(mddev
->new_layout
))) {
5733 printk(KERN_ERR
"md/raid:%s: layout %d not supported\n",
5734 mdname(mddev
), mddev
->new_layout
);
5735 return ERR_PTR(-EIO
);
5737 if (mddev
->new_level
== 6 && mddev
->raid_disks
< 4) {
5738 printk(KERN_ERR
"md/raid:%s: not enough configured devices (%d, minimum 4)\n",
5739 mdname(mddev
), mddev
->raid_disks
);
5740 return ERR_PTR(-EINVAL
);
5743 if (!mddev
->new_chunk_sectors
||
5744 (mddev
->new_chunk_sectors
<< 9) % PAGE_SIZE
||
5745 !is_power_of_2(mddev
->new_chunk_sectors
)) {
5746 printk(KERN_ERR
"md/raid:%s: invalid chunk size %d\n",
5747 mdname(mddev
), mddev
->new_chunk_sectors
<< 9);
5748 return ERR_PTR(-EINVAL
);
5751 conf
= kzalloc(sizeof(struct r5conf
), GFP_KERNEL
);
5754 /* Don't enable multi-threading by default*/
5755 if (!alloc_thread_groups(conf
, 0, &group_cnt
, &worker_cnt_per_group
,
5757 conf
->group_cnt
= group_cnt
;
5758 conf
->worker_cnt_per_group
= worker_cnt_per_group
;
5759 conf
->worker_groups
= new_group
;
5762 spin_lock_init(&conf
->device_lock
);
5763 seqcount_init(&conf
->gen_lock
);
5764 init_waitqueue_head(&conf
->wait_for_stripe
);
5765 init_waitqueue_head(&conf
->wait_for_overlap
);
5766 INIT_LIST_HEAD(&conf
->handle_list
);
5767 INIT_LIST_HEAD(&conf
->hold_list
);
5768 INIT_LIST_HEAD(&conf
->delayed_list
);
5769 INIT_LIST_HEAD(&conf
->bitmap_list
);
5770 init_llist_head(&conf
->released_stripes
);
5771 atomic_set(&conf
->active_stripes
, 0);
5772 atomic_set(&conf
->preread_active_stripes
, 0);
5773 atomic_set(&conf
->active_aligned_reads
, 0);
5774 conf
->bypass_threshold
= BYPASS_THRESHOLD
;
5775 conf
->recovery_disabled
= mddev
->recovery_disabled
- 1;
5777 conf
->raid_disks
= mddev
->raid_disks
;
5778 if (mddev
->reshape_position
== MaxSector
)
5779 conf
->previous_raid_disks
= mddev
->raid_disks
;
5781 conf
->previous_raid_disks
= mddev
->raid_disks
- mddev
->delta_disks
;
5782 max_disks
= max(conf
->raid_disks
, conf
->previous_raid_disks
);
5783 conf
->scribble_len
= scribble_len(max_disks
);
5785 conf
->disks
= kzalloc(max_disks
* sizeof(struct disk_info
),
5790 conf
->mddev
= mddev
;
5792 if ((conf
->stripe_hashtbl
= kzalloc(PAGE_SIZE
, GFP_KERNEL
)) == NULL
)
5795 /* We init hash_locks[0] separately to that it can be used
5796 * as the reference lock in the spin_lock_nest_lock() call
5797 * in lock_all_device_hash_locks_irq in order to convince
5798 * lockdep that we know what we are doing.
5800 spin_lock_init(conf
->hash_locks
);
5801 for (i
= 1; i
< NR_STRIPE_HASH_LOCKS
; i
++)
5802 spin_lock_init(conf
->hash_locks
+ i
);
5804 for (i
= 0; i
< NR_STRIPE_HASH_LOCKS
; i
++)
5805 INIT_LIST_HEAD(conf
->inactive_list
+ i
);
5807 for (i
= 0; i
< NR_STRIPE_HASH_LOCKS
; i
++)
5808 INIT_LIST_HEAD(conf
->temp_inactive_list
+ i
);
5810 conf
->level
= mddev
->new_level
;
5811 if (raid5_alloc_percpu(conf
) != 0)
5814 pr_debug("raid456: run(%s) called.\n", mdname(mddev
));
5816 rdev_for_each(rdev
, mddev
) {
5817 raid_disk
= rdev
->raid_disk
;
5818 if (raid_disk
>= max_disks
5821 disk
= conf
->disks
+ raid_disk
;
5823 if (test_bit(Replacement
, &rdev
->flags
)) {
5824 if (disk
->replacement
)
5826 disk
->replacement
= rdev
;
5833 if (test_bit(In_sync
, &rdev
->flags
)) {
5834 char b
[BDEVNAME_SIZE
];
5835 printk(KERN_INFO
"md/raid:%s: device %s operational as raid"
5837 mdname(mddev
), bdevname(rdev
->bdev
, b
), raid_disk
);
5838 } else if (rdev
->saved_raid_disk
!= raid_disk
)
5839 /* Cannot rely on bitmap to complete recovery */
5843 conf
->chunk_sectors
= mddev
->new_chunk_sectors
;
5844 conf
->level
= mddev
->new_level
;
5845 if (conf
->level
== 6)
5846 conf
->max_degraded
= 2;
5848 conf
->max_degraded
= 1;
5849 conf
->algorithm
= mddev
->new_layout
;
5850 conf
->reshape_progress
= mddev
->reshape_position
;
5851 if (conf
->reshape_progress
!= MaxSector
) {
5852 conf
->prev_chunk_sectors
= mddev
->chunk_sectors
;
5853 conf
->prev_algo
= mddev
->layout
;
5856 memory
= conf
->max_nr_stripes
* (sizeof(struct stripe_head
) +
5857 max_disks
* ((sizeof(struct bio
) + PAGE_SIZE
))) / 1024;
5858 atomic_set(&conf
->empty_inactive_list_nr
, NR_STRIPE_HASH_LOCKS
);
5859 if (grow_stripes(conf
, NR_STRIPES
)) {
5861 "md/raid:%s: couldn't allocate %dkB for buffers\n",
5862 mdname(mddev
), memory
);
5865 printk(KERN_INFO
"md/raid:%s: allocated %dkB\n",
5866 mdname(mddev
), memory
);
5868 sprintf(pers_name
, "raid%d", mddev
->new_level
);
5869 conf
->thread
= md_register_thread(raid5d
, mddev
, pers_name
);
5870 if (!conf
->thread
) {
5872 "md/raid:%s: couldn't allocate thread.\n",
5882 return ERR_PTR(-EIO
);
5884 return ERR_PTR(-ENOMEM
);
5887 static int only_parity(int raid_disk
, int algo
, int raid_disks
, int max_degraded
)
5890 case ALGORITHM_PARITY_0
:
5891 if (raid_disk
< max_degraded
)
5894 case ALGORITHM_PARITY_N
:
5895 if (raid_disk
>= raid_disks
- max_degraded
)
5898 case ALGORITHM_PARITY_0_6
:
5899 if (raid_disk
== 0 ||
5900 raid_disk
== raid_disks
- 1)
5903 case ALGORITHM_LEFT_ASYMMETRIC_6
:
5904 case ALGORITHM_RIGHT_ASYMMETRIC_6
:
5905 case ALGORITHM_LEFT_SYMMETRIC_6
:
5906 case ALGORITHM_RIGHT_SYMMETRIC_6
:
5907 if (raid_disk
== raid_disks
- 1)
5913 static int run(struct mddev
*mddev
)
5915 struct r5conf
*conf
;
5916 int working_disks
= 0;
5917 int dirty_parity_disks
= 0;
5918 struct md_rdev
*rdev
;
5919 sector_t reshape_offset
= 0;
5921 long long min_offset_diff
= 0;
5924 if (mddev
->recovery_cp
!= MaxSector
)
5925 printk(KERN_NOTICE
"md/raid:%s: not clean"
5926 " -- starting background reconstruction\n",
5929 rdev_for_each(rdev
, mddev
) {
5931 if (rdev
->raid_disk
< 0)
5933 diff
= (rdev
->new_data_offset
- rdev
->data_offset
);
5935 min_offset_diff
= diff
;
5937 } else if (mddev
->reshape_backwards
&&
5938 diff
< min_offset_diff
)
5939 min_offset_diff
= diff
;
5940 else if (!mddev
->reshape_backwards
&&
5941 diff
> min_offset_diff
)
5942 min_offset_diff
= diff
;
5945 if (mddev
->reshape_position
!= MaxSector
) {
5946 /* Check that we can continue the reshape.
5947 * Difficulties arise if the stripe we would write to
5948 * next is at or after the stripe we would read from next.
5949 * For a reshape that changes the number of devices, this
5950 * is only possible for a very short time, and mdadm makes
5951 * sure that time appears to have past before assembling
5952 * the array. So we fail if that time hasn't passed.
5953 * For a reshape that keeps the number of devices the same
5954 * mdadm must be monitoring the reshape can keeping the
5955 * critical areas read-only and backed up. It will start
5956 * the array in read-only mode, so we check for that.
5958 sector_t here_new
, here_old
;
5960 int max_degraded
= (mddev
->level
== 6 ? 2 : 1);
5962 if (mddev
->new_level
!= mddev
->level
) {
5963 printk(KERN_ERR
"md/raid:%s: unsupported reshape "
5964 "required - aborting.\n",
5968 old_disks
= mddev
->raid_disks
- mddev
->delta_disks
;
5969 /* reshape_position must be on a new-stripe boundary, and one
5970 * further up in new geometry must map after here in old
5973 here_new
= mddev
->reshape_position
;
5974 if (sector_div(here_new
, mddev
->new_chunk_sectors
*
5975 (mddev
->raid_disks
- max_degraded
))) {
5976 printk(KERN_ERR
"md/raid:%s: reshape_position not "
5977 "on a stripe boundary\n", mdname(mddev
));
5980 reshape_offset
= here_new
* mddev
->new_chunk_sectors
;
5981 /* here_new is the stripe we will write to */
5982 here_old
= mddev
->reshape_position
;
5983 sector_div(here_old
, mddev
->chunk_sectors
*
5984 (old_disks
-max_degraded
));
5985 /* here_old is the first stripe that we might need to read
5987 if (mddev
->delta_disks
== 0) {
5988 if ((here_new
* mddev
->new_chunk_sectors
!=
5989 here_old
* mddev
->chunk_sectors
)) {
5990 printk(KERN_ERR
"md/raid:%s: reshape position is"
5991 " confused - aborting\n", mdname(mddev
));
5994 /* We cannot be sure it is safe to start an in-place
5995 * reshape. It is only safe if user-space is monitoring
5996 * and taking constant backups.
5997 * mdadm always starts a situation like this in
5998 * readonly mode so it can take control before
5999 * allowing any writes. So just check for that.
6001 if (abs(min_offset_diff
) >= mddev
->chunk_sectors
&&
6002 abs(min_offset_diff
) >= mddev
->new_chunk_sectors
)
6003 /* not really in-place - so OK */;
6004 else if (mddev
->ro
== 0) {
6005 printk(KERN_ERR
"md/raid:%s: in-place reshape "
6006 "must be started in read-only mode "
6011 } else if (mddev
->reshape_backwards
6012 ? (here_new
* mddev
->new_chunk_sectors
+ min_offset_diff
<=
6013 here_old
* mddev
->chunk_sectors
)
6014 : (here_new
* mddev
->new_chunk_sectors
>=
6015 here_old
* mddev
->chunk_sectors
+ (-min_offset_diff
))) {
6016 /* Reading from the same stripe as writing to - bad */
6017 printk(KERN_ERR
"md/raid:%s: reshape_position too early for "
6018 "auto-recovery - aborting.\n",
6022 printk(KERN_INFO
"md/raid:%s: reshape will continue\n",
6024 /* OK, we should be able to continue; */
6026 BUG_ON(mddev
->level
!= mddev
->new_level
);
6027 BUG_ON(mddev
->layout
!= mddev
->new_layout
);
6028 BUG_ON(mddev
->chunk_sectors
!= mddev
->new_chunk_sectors
);
6029 BUG_ON(mddev
->delta_disks
!= 0);
6032 if (mddev
->private == NULL
)
6033 conf
= setup_conf(mddev
);
6035 conf
= mddev
->private;
6038 return PTR_ERR(conf
);
6040 conf
->min_offset_diff
= min_offset_diff
;
6041 mddev
->thread
= conf
->thread
;
6042 conf
->thread
= NULL
;
6043 mddev
->private = conf
;
6045 for (i
= 0; i
< conf
->raid_disks
&& conf
->previous_raid_disks
;
6047 rdev
= conf
->disks
[i
].rdev
;
6048 if (!rdev
&& conf
->disks
[i
].replacement
) {
6049 /* The replacement is all we have yet */
6050 rdev
= conf
->disks
[i
].replacement
;
6051 conf
->disks
[i
].replacement
= NULL
;
6052 clear_bit(Replacement
, &rdev
->flags
);
6053 conf
->disks
[i
].rdev
= rdev
;
6057 if (conf
->disks
[i
].replacement
&&
6058 conf
->reshape_progress
!= MaxSector
) {
6059 /* replacements and reshape simply do not mix. */
6060 printk(KERN_ERR
"md: cannot handle concurrent "
6061 "replacement and reshape.\n");
6064 if (test_bit(In_sync
, &rdev
->flags
)) {
6068 /* This disc is not fully in-sync. However if it
6069 * just stored parity (beyond the recovery_offset),
6070 * when we don't need to be concerned about the
6071 * array being dirty.
6072 * When reshape goes 'backwards', we never have
6073 * partially completed devices, so we only need
6074 * to worry about reshape going forwards.
6076 /* Hack because v0.91 doesn't store recovery_offset properly. */
6077 if (mddev
->major_version
== 0 &&
6078 mddev
->minor_version
> 90)
6079 rdev
->recovery_offset
= reshape_offset
;
6081 if (rdev
->recovery_offset
< reshape_offset
) {
6082 /* We need to check old and new layout */
6083 if (!only_parity(rdev
->raid_disk
,
6086 conf
->max_degraded
))
6089 if (!only_parity(rdev
->raid_disk
,
6091 conf
->previous_raid_disks
,
6092 conf
->max_degraded
))
6094 dirty_parity_disks
++;
6098 * 0 for a fully functional array, 1 or 2 for a degraded array.
6100 mddev
->degraded
= calc_degraded(conf
);
6102 if (has_failed(conf
)) {
6103 printk(KERN_ERR
"md/raid:%s: not enough operational devices"
6104 " (%d/%d failed)\n",
6105 mdname(mddev
), mddev
->degraded
, conf
->raid_disks
);
6109 /* device size must be a multiple of chunk size */
6110 mddev
->dev_sectors
&= ~(mddev
->chunk_sectors
- 1);
6111 mddev
->resync_max_sectors
= mddev
->dev_sectors
;
6113 if (mddev
->degraded
> dirty_parity_disks
&&
6114 mddev
->recovery_cp
!= MaxSector
) {
6115 if (mddev
->ok_start_degraded
)
6117 "md/raid:%s: starting dirty degraded array"
6118 " - data corruption possible.\n",
6122 "md/raid:%s: cannot start dirty degraded array.\n",
6128 if (mddev
->degraded
== 0)
6129 printk(KERN_INFO
"md/raid:%s: raid level %d active with %d out of %d"
6130 " devices, algorithm %d\n", mdname(mddev
), conf
->level
,
6131 mddev
->raid_disks
-mddev
->degraded
, mddev
->raid_disks
,
6134 printk(KERN_ALERT
"md/raid:%s: raid level %d active with %d"
6135 " out of %d devices, algorithm %d\n",
6136 mdname(mddev
), conf
->level
,
6137 mddev
->raid_disks
- mddev
->degraded
,
6138 mddev
->raid_disks
, mddev
->new_layout
);
6140 print_raid5_conf(conf
);
6142 if (conf
->reshape_progress
!= MaxSector
) {
6143 conf
->reshape_safe
= conf
->reshape_progress
;
6144 atomic_set(&conf
->reshape_stripes
, 0);
6145 clear_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
);
6146 clear_bit(MD_RECOVERY_CHECK
, &mddev
->recovery
);
6147 set_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
);
6148 set_bit(MD_RECOVERY_RUNNING
, &mddev
->recovery
);
6149 mddev
->sync_thread
= md_register_thread(md_do_sync
, mddev
,
6153 /* Ok, everything is just fine now */
6154 if (mddev
->to_remove
== &raid5_attrs_group
)
6155 mddev
->to_remove
= NULL
;
6156 else if (mddev
->kobj
.sd
&&
6157 sysfs_create_group(&mddev
->kobj
, &raid5_attrs_group
))
6159 "raid5: failed to create sysfs attributes for %s\n",
6161 md_set_array_sectors(mddev
, raid5_size(mddev
, 0, 0));
6165 bool discard_supported
= true;
6166 /* read-ahead size must cover two whole stripes, which
6167 * is 2 * (datadisks) * chunksize where 'n' is the
6168 * number of raid devices
6170 int data_disks
= conf
->previous_raid_disks
- conf
->max_degraded
;
6171 int stripe
= data_disks
*
6172 ((mddev
->chunk_sectors
<< 9) / PAGE_SIZE
);
6173 if (mddev
->queue
->backing_dev_info
.ra_pages
< 2 * stripe
)
6174 mddev
->queue
->backing_dev_info
.ra_pages
= 2 * stripe
;
6176 blk_queue_merge_bvec(mddev
->queue
, raid5_mergeable_bvec
);
6178 mddev
->queue
->backing_dev_info
.congested_data
= mddev
;
6179 mddev
->queue
->backing_dev_info
.congested_fn
= raid5_congested
;
6181 chunk_size
= mddev
->chunk_sectors
<< 9;
6182 blk_queue_io_min(mddev
->queue
, chunk_size
);
6183 blk_queue_io_opt(mddev
->queue
, chunk_size
*
6184 (conf
->raid_disks
- conf
->max_degraded
));
6185 mddev
->queue
->limits
.raid_partial_stripes_expensive
= 1;
6187 * We can only discard a whole stripe. It doesn't make sense to
6188 * discard data disk but write parity disk
6190 stripe
= stripe
* PAGE_SIZE
;
6191 /* Round up to power of 2, as discard handling
6192 * currently assumes that */
6193 while ((stripe
-1) & stripe
)
6194 stripe
= (stripe
| (stripe
-1)) + 1;
6195 mddev
->queue
->limits
.discard_alignment
= stripe
;
6196 mddev
->queue
->limits
.discard_granularity
= stripe
;
6198 * unaligned part of discard request will be ignored, so can't
6199 * guarantee discard_zeroes_data
6201 mddev
->queue
->limits
.discard_zeroes_data
= 0;
6203 blk_queue_max_write_same_sectors(mddev
->queue
, 0);
6205 rdev_for_each(rdev
, mddev
) {
6206 disk_stack_limits(mddev
->gendisk
, rdev
->bdev
,
6207 rdev
->data_offset
<< 9);
6208 disk_stack_limits(mddev
->gendisk
, rdev
->bdev
,
6209 rdev
->new_data_offset
<< 9);
6211 * discard_zeroes_data is required, otherwise data
6212 * could be lost. Consider a scenario: discard a stripe
6213 * (the stripe could be inconsistent if
6214 * discard_zeroes_data is 0); write one disk of the
6215 * stripe (the stripe could be inconsistent again
6216 * depending on which disks are used to calculate
6217 * parity); the disk is broken; The stripe data of this
6220 if (!blk_queue_discard(bdev_get_queue(rdev
->bdev
)) ||
6221 !bdev_get_queue(rdev
->bdev
)->
6222 limits
.discard_zeroes_data
)
6223 discard_supported
= false;
6224 /* Unfortunately, discard_zeroes_data is not currently
6225 * a guarantee - just a hint. So we only allow DISCARD
6226 * if the sysadmin has confirmed that only safe devices
6227 * are in use by setting a module parameter.
6229 if (!devices_handle_discard_safely
) {
6230 if (discard_supported
) {
6231 pr_info("md/raid456: discard support disabled due to uncertainty.\n");
6232 pr_info("Set raid456.devices_handle_discard_safely=Y to override.\n");
6234 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
);
6801 static void *raid45_takeover_raid0(struct mddev
*mddev
, int level
)
6803 struct r0conf
*raid0_conf
= mddev
->private;
6806 /* for raid0 takeover only one zone is supported */
6807 if (raid0_conf
->nr_strip_zones
> 1) {
6808 printk(KERN_ERR
"md/raid:%s: cannot takeover raid0 with more than one zone.\n",
6810 return ERR_PTR(-EINVAL
);
6813 sectors
= raid0_conf
->strip_zone
[0].zone_end
;
6814 sector_div(sectors
, raid0_conf
->strip_zone
[0].nb_dev
);
6815 mddev
->dev_sectors
= sectors
;
6816 mddev
->new_level
= level
;
6817 mddev
->new_layout
= ALGORITHM_PARITY_N
;
6818 mddev
->new_chunk_sectors
= mddev
->chunk_sectors
;
6819 mddev
->raid_disks
+= 1;
6820 mddev
->delta_disks
= 1;
6821 /* make sure it will be not marked as dirty */
6822 mddev
->recovery_cp
= MaxSector
;
6824 return setup_conf(mddev
);
6827 static void *raid5_takeover_raid1(struct mddev
*mddev
)
6831 if (mddev
->raid_disks
!= 2 ||
6832 mddev
->degraded
> 1)
6833 return ERR_PTR(-EINVAL
);
6835 /* Should check if there are write-behind devices? */
6837 chunksect
= 64*2; /* 64K by default */
6839 /* The array must be an exact multiple of chunksize */
6840 while (chunksect
&& (mddev
->array_sectors
& (chunksect
-1)))
6843 if ((chunksect
<<9) < STRIPE_SIZE
)
6844 /* array size does not allow a suitable chunk size */
6845 return ERR_PTR(-EINVAL
);
6847 mddev
->new_level
= 5;
6848 mddev
->new_layout
= ALGORITHM_LEFT_SYMMETRIC
;
6849 mddev
->new_chunk_sectors
= chunksect
;
6851 return setup_conf(mddev
);
6854 static void *raid5_takeover_raid6(struct mddev
*mddev
)
6858 switch (mddev
->layout
) {
6859 case ALGORITHM_LEFT_ASYMMETRIC_6
:
6860 new_layout
= ALGORITHM_LEFT_ASYMMETRIC
;
6862 case ALGORITHM_RIGHT_ASYMMETRIC_6
:
6863 new_layout
= ALGORITHM_RIGHT_ASYMMETRIC
;
6865 case ALGORITHM_LEFT_SYMMETRIC_6
:
6866 new_layout
= ALGORITHM_LEFT_SYMMETRIC
;
6868 case ALGORITHM_RIGHT_SYMMETRIC_6
:
6869 new_layout
= ALGORITHM_RIGHT_SYMMETRIC
;
6871 case ALGORITHM_PARITY_0_6
:
6872 new_layout
= ALGORITHM_PARITY_0
;
6874 case ALGORITHM_PARITY_N
:
6875 new_layout
= ALGORITHM_PARITY_N
;
6878 return ERR_PTR(-EINVAL
);
6880 mddev
->new_level
= 5;
6881 mddev
->new_layout
= new_layout
;
6882 mddev
->delta_disks
= -1;
6883 mddev
->raid_disks
-= 1;
6884 return setup_conf(mddev
);
6887 static int raid5_check_reshape(struct mddev
*mddev
)
6889 /* For a 2-drive array, the layout and chunk size can be changed
6890 * immediately as not restriping is needed.
6891 * For larger arrays we record the new value - after validation
6892 * to be used by a reshape pass.
6894 struct r5conf
*conf
= mddev
->private;
6895 int new_chunk
= mddev
->new_chunk_sectors
;
6897 if (mddev
->new_layout
>= 0 && !algorithm_valid_raid5(mddev
->new_layout
))
6899 if (new_chunk
> 0) {
6900 if (!is_power_of_2(new_chunk
))
6902 if (new_chunk
< (PAGE_SIZE
>>9))
6904 if (mddev
->array_sectors
& (new_chunk
-1))
6905 /* not factor of array size */
6909 /* They look valid */
6911 if (mddev
->raid_disks
== 2) {
6912 /* can make the change immediately */
6913 if (mddev
->new_layout
>= 0) {
6914 conf
->algorithm
= mddev
->new_layout
;
6915 mddev
->layout
= mddev
->new_layout
;
6917 if (new_chunk
> 0) {
6918 conf
->chunk_sectors
= new_chunk
;
6919 mddev
->chunk_sectors
= new_chunk
;
6921 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
6922 md_wakeup_thread(mddev
->thread
);
6924 return check_reshape(mddev
);
6927 static int raid6_check_reshape(struct mddev
*mddev
)
6929 int new_chunk
= mddev
->new_chunk_sectors
;
6931 if (mddev
->new_layout
>= 0 && !algorithm_valid_raid6(mddev
->new_layout
))
6933 if (new_chunk
> 0) {
6934 if (!is_power_of_2(new_chunk
))
6936 if (new_chunk
< (PAGE_SIZE
>> 9))
6938 if (mddev
->array_sectors
& (new_chunk
-1))
6939 /* not factor of array size */
6943 /* They look valid */
6944 return check_reshape(mddev
);
6947 static void *raid5_takeover(struct mddev
*mddev
)
6949 /* raid5 can take over:
6950 * raid0 - if there is only one strip zone - make it a raid4 layout
6951 * raid1 - if there are two drives. We need to know the chunk size
6952 * raid4 - trivial - just use a raid4 layout.
6953 * raid6 - Providing it is a *_6 layout
6955 if (mddev
->level
== 0)
6956 return raid45_takeover_raid0(mddev
, 5);
6957 if (mddev
->level
== 1)
6958 return raid5_takeover_raid1(mddev
);
6959 if (mddev
->level
== 4) {
6960 mddev
->new_layout
= ALGORITHM_PARITY_N
;
6961 mddev
->new_level
= 5;
6962 return setup_conf(mddev
);
6964 if (mddev
->level
== 6)
6965 return raid5_takeover_raid6(mddev
);
6967 return ERR_PTR(-EINVAL
);
6970 static void *raid4_takeover(struct mddev
*mddev
)
6972 /* raid4 can take over:
6973 * raid0 - if there is only one strip zone
6974 * raid5 - if layout is right
6976 if (mddev
->level
== 0)
6977 return raid45_takeover_raid0(mddev
, 4);
6978 if (mddev
->level
== 5 &&
6979 mddev
->layout
== ALGORITHM_PARITY_N
) {
6980 mddev
->new_layout
= 0;
6981 mddev
->new_level
= 4;
6982 return setup_conf(mddev
);
6984 return ERR_PTR(-EINVAL
);
6987 static struct md_personality raid5_personality
;
6989 static void *raid6_takeover(struct mddev
*mddev
)
6991 /* Currently can only take over a raid5. We map the
6992 * personality to an equivalent raid6 personality
6993 * with the Q block at the end.
6997 if (mddev
->pers
!= &raid5_personality
)
6998 return ERR_PTR(-EINVAL
);
6999 if (mddev
->degraded
> 1)
7000 return ERR_PTR(-EINVAL
);
7001 if (mddev
->raid_disks
> 253)
7002 return ERR_PTR(-EINVAL
);
7003 if (mddev
->raid_disks
< 3)
7004 return ERR_PTR(-EINVAL
);
7006 switch (mddev
->layout
) {
7007 case ALGORITHM_LEFT_ASYMMETRIC
:
7008 new_layout
= ALGORITHM_LEFT_ASYMMETRIC_6
;
7010 case ALGORITHM_RIGHT_ASYMMETRIC
:
7011 new_layout
= ALGORITHM_RIGHT_ASYMMETRIC_6
;
7013 case ALGORITHM_LEFT_SYMMETRIC
:
7014 new_layout
= ALGORITHM_LEFT_SYMMETRIC_6
;
7016 case ALGORITHM_RIGHT_SYMMETRIC
:
7017 new_layout
= ALGORITHM_RIGHT_SYMMETRIC_6
;
7019 case ALGORITHM_PARITY_0
:
7020 new_layout
= ALGORITHM_PARITY_0_6
;
7022 case ALGORITHM_PARITY_N
:
7023 new_layout
= ALGORITHM_PARITY_N
;
7026 return ERR_PTR(-EINVAL
);
7028 mddev
->new_level
= 6;
7029 mddev
->new_layout
= new_layout
;
7030 mddev
->delta_disks
= 1;
7031 mddev
->raid_disks
+= 1;
7032 return setup_conf(mddev
);
7035 static struct md_personality raid6_personality
=
7039 .owner
= THIS_MODULE
,
7040 .make_request
= make_request
,
7044 .error_handler
= error
,
7045 .hot_add_disk
= raid5_add_disk
,
7046 .hot_remove_disk
= raid5_remove_disk
,
7047 .spare_active
= raid5_spare_active
,
7048 .sync_request
= sync_request
,
7049 .resize
= raid5_resize
,
7051 .check_reshape
= raid6_check_reshape
,
7052 .start_reshape
= raid5_start_reshape
,
7053 .finish_reshape
= raid5_finish_reshape
,
7054 .quiesce
= raid5_quiesce
,
7055 .takeover
= raid6_takeover
,
7057 static struct md_personality raid5_personality
=
7061 .owner
= THIS_MODULE
,
7062 .make_request
= make_request
,
7066 .error_handler
= error
,
7067 .hot_add_disk
= raid5_add_disk
,
7068 .hot_remove_disk
= raid5_remove_disk
,
7069 .spare_active
= raid5_spare_active
,
7070 .sync_request
= sync_request
,
7071 .resize
= raid5_resize
,
7073 .check_reshape
= raid5_check_reshape
,
7074 .start_reshape
= raid5_start_reshape
,
7075 .finish_reshape
= raid5_finish_reshape
,
7076 .quiesce
= raid5_quiesce
,
7077 .takeover
= raid5_takeover
,
7080 static struct md_personality raid4_personality
=
7084 .owner
= THIS_MODULE
,
7085 .make_request
= make_request
,
7089 .error_handler
= error
,
7090 .hot_add_disk
= raid5_add_disk
,
7091 .hot_remove_disk
= raid5_remove_disk
,
7092 .spare_active
= raid5_spare_active
,
7093 .sync_request
= sync_request
,
7094 .resize
= raid5_resize
,
7096 .check_reshape
= raid5_check_reshape
,
7097 .start_reshape
= raid5_start_reshape
,
7098 .finish_reshape
= raid5_finish_reshape
,
7099 .quiesce
= raid5_quiesce
,
7100 .takeover
= raid4_takeover
,
7103 static int __init
raid5_init(void)
7105 raid5_wq
= alloc_workqueue("raid5wq",
7106 WQ_UNBOUND
|WQ_MEM_RECLAIM
|WQ_CPU_INTENSIVE
|WQ_SYSFS
, 0);
7109 register_md_personality(&raid6_personality
);
7110 register_md_personality(&raid5_personality
);
7111 register_md_personality(&raid4_personality
);
7115 static void raid5_exit(void)
7117 unregister_md_personality(&raid6_personality
);
7118 unregister_md_personality(&raid5_personality
);
7119 unregister_md_personality(&raid4_personality
);
7120 destroy_workqueue(raid5_wq
);
7123 module_init(raid5_init
);
7124 module_exit(raid5_exit
);
7125 MODULE_LICENSE("GPL");
7126 MODULE_DESCRIPTION("RAID4/5/6 (striping with parity) personality for MD");
7127 MODULE_ALIAS("md-personality-4"); /* RAID5 */
7128 MODULE_ALIAS("md-raid5");
7129 MODULE_ALIAS("md-raid4");
7130 MODULE_ALIAS("md-level-5");
7131 MODULE_ALIAS("md-level-4");
7132 MODULE_ALIAS("md-personality-8"); /* RAID6 */
7133 MODULE_ALIAS("md-raid6");
7134 MODULE_ALIAS("md-level-6");
7136 /* This used to be two separate modules, they were: */
7137 MODULE_ALIAS("raid5");
7138 MODULE_ALIAS("raid6");