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 <linux/flex_array.h>
58 #include <trace/events/block.h>
65 #define cpu_to_group(cpu) cpu_to_node(cpu)
66 #define ANY_GROUP NUMA_NO_NODE
68 static bool devices_handle_discard_safely
= false;
69 module_param(devices_handle_discard_safely
, bool, 0644);
70 MODULE_PARM_DESC(devices_handle_discard_safely
,
71 "Set to Y if all devices in each array reliably return zeroes on reads from discarded regions");
72 static struct workqueue_struct
*raid5_wq
;
77 #define NR_STRIPES 256
78 #define STRIPE_SIZE PAGE_SIZE
79 #define STRIPE_SHIFT (PAGE_SHIFT - 9)
80 #define STRIPE_SECTORS (STRIPE_SIZE>>9)
81 #define IO_THRESHOLD 1
82 #define BYPASS_THRESHOLD 1
83 #define NR_HASH (PAGE_SIZE / sizeof(struct hlist_head))
84 #define HASH_MASK (NR_HASH - 1)
85 #define MAX_STRIPE_BATCH 8
87 static inline struct hlist_head
*stripe_hash(struct r5conf
*conf
, sector_t sect
)
89 int hash
= (sect
>> STRIPE_SHIFT
) & HASH_MASK
;
90 return &conf
->stripe_hashtbl
[hash
];
93 static inline int stripe_hash_locks_hash(sector_t sect
)
95 return (sect
>> STRIPE_SHIFT
) & STRIPE_HASH_LOCKS_MASK
;
98 static inline void lock_device_hash_lock(struct r5conf
*conf
, int hash
)
100 spin_lock_irq(conf
->hash_locks
+ hash
);
101 spin_lock(&conf
->device_lock
);
104 static inline void unlock_device_hash_lock(struct r5conf
*conf
, int hash
)
106 spin_unlock(&conf
->device_lock
);
107 spin_unlock_irq(conf
->hash_locks
+ hash
);
110 static inline void lock_all_device_hash_locks_irq(struct r5conf
*conf
)
114 spin_lock(conf
->hash_locks
);
115 for (i
= 1; i
< NR_STRIPE_HASH_LOCKS
; i
++)
116 spin_lock_nest_lock(conf
->hash_locks
+ i
, conf
->hash_locks
);
117 spin_lock(&conf
->device_lock
);
120 static inline void unlock_all_device_hash_locks_irq(struct r5conf
*conf
)
123 spin_unlock(&conf
->device_lock
);
124 for (i
= NR_STRIPE_HASH_LOCKS
; i
; i
--)
125 spin_unlock(conf
->hash_locks
+ i
- 1);
129 /* bio's attached to a stripe+device for I/O are linked together in bi_sector
130 * order without overlap. There may be several bio's per stripe+device, and
131 * a bio could span several devices.
132 * When walking this list for a particular stripe+device, we must never proceed
133 * beyond a bio that extends past this device, as the next bio might no longer
135 * This function is used to determine the 'next' bio in the list, given the sector
136 * of the current stripe+device
138 static inline struct bio
*r5_next_bio(struct bio
*bio
, sector_t sector
)
140 int sectors
= bio_sectors(bio
);
141 if (bio
->bi_iter
.bi_sector
+ sectors
< sector
+ STRIPE_SECTORS
)
148 * We maintain a biased count of active stripes in the bottom 16 bits of
149 * bi_phys_segments, and a count of processed stripes in the upper 16 bits
151 static inline int raid5_bi_processed_stripes(struct bio
*bio
)
153 atomic_t
*segments
= (atomic_t
*)&bio
->bi_phys_segments
;
154 return (atomic_read(segments
) >> 16) & 0xffff;
157 static inline int raid5_dec_bi_active_stripes(struct bio
*bio
)
159 atomic_t
*segments
= (atomic_t
*)&bio
->bi_phys_segments
;
160 return atomic_sub_return(1, segments
) & 0xffff;
163 static inline void raid5_inc_bi_active_stripes(struct bio
*bio
)
165 atomic_t
*segments
= (atomic_t
*)&bio
->bi_phys_segments
;
166 atomic_inc(segments
);
169 static inline void raid5_set_bi_processed_stripes(struct bio
*bio
,
172 atomic_t
*segments
= (atomic_t
*)&bio
->bi_phys_segments
;
176 old
= atomic_read(segments
);
177 new = (old
& 0xffff) | (cnt
<< 16);
178 } while (atomic_cmpxchg(segments
, old
, new) != old
);
181 static inline void raid5_set_bi_stripes(struct bio
*bio
, unsigned int cnt
)
183 atomic_t
*segments
= (atomic_t
*)&bio
->bi_phys_segments
;
184 atomic_set(segments
, cnt
);
187 /* Find first data disk in a raid6 stripe */
188 static inline int raid6_d0(struct stripe_head
*sh
)
191 /* ddf always start from first device */
193 /* md starts just after Q block */
194 if (sh
->qd_idx
== sh
->disks
- 1)
197 return sh
->qd_idx
+ 1;
199 static inline int raid6_next_disk(int disk
, int raid_disks
)
202 return (disk
< raid_disks
) ? disk
: 0;
205 /* When walking through the disks in a raid5, starting at raid6_d0,
206 * We need to map each disk to a 'slot', where the data disks are slot
207 * 0 .. raid_disks-3, the parity disk is raid_disks-2 and the Q disk
208 * is raid_disks-1. This help does that mapping.
210 static int raid6_idx_to_slot(int idx
, struct stripe_head
*sh
,
211 int *count
, int syndrome_disks
)
217 if (idx
== sh
->pd_idx
)
218 return syndrome_disks
;
219 if (idx
== sh
->qd_idx
)
220 return syndrome_disks
+ 1;
226 static void return_io(struct bio
*return_bi
)
228 struct bio
*bi
= return_bi
;
231 return_bi
= bi
->bi_next
;
233 bi
->bi_iter
.bi_size
= 0;
234 trace_block_bio_complete(bdev_get_queue(bi
->bi_bdev
),
241 static void print_raid5_conf (struct r5conf
*conf
);
243 static int stripe_operations_active(struct stripe_head
*sh
)
245 return sh
->check_state
|| sh
->reconstruct_state
||
246 test_bit(STRIPE_BIOFILL_RUN
, &sh
->state
) ||
247 test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
250 static void raid5_wakeup_stripe_thread(struct stripe_head
*sh
)
252 struct r5conf
*conf
= sh
->raid_conf
;
253 struct r5worker_group
*group
;
255 int i
, cpu
= sh
->cpu
;
257 if (!cpu_online(cpu
)) {
258 cpu
= cpumask_any(cpu_online_mask
);
262 if (list_empty(&sh
->lru
)) {
263 struct r5worker_group
*group
;
264 group
= conf
->worker_groups
+ cpu_to_group(cpu
);
265 list_add_tail(&sh
->lru
, &group
->handle_list
);
266 group
->stripes_cnt
++;
270 if (conf
->worker_cnt_per_group
== 0) {
271 md_wakeup_thread(conf
->mddev
->thread
);
275 group
= conf
->worker_groups
+ cpu_to_group(sh
->cpu
);
277 group
->workers
[0].working
= true;
278 /* at least one worker should run to avoid race */
279 queue_work_on(sh
->cpu
, raid5_wq
, &group
->workers
[0].work
);
281 thread_cnt
= group
->stripes_cnt
/ MAX_STRIPE_BATCH
- 1;
282 /* wakeup more workers */
283 for (i
= 1; i
< conf
->worker_cnt_per_group
&& thread_cnt
> 0; i
++) {
284 if (group
->workers
[i
].working
== false) {
285 group
->workers
[i
].working
= true;
286 queue_work_on(sh
->cpu
, raid5_wq
,
287 &group
->workers
[i
].work
);
293 static void do_release_stripe(struct r5conf
*conf
, struct stripe_head
*sh
,
294 struct list_head
*temp_inactive_list
)
296 BUG_ON(!list_empty(&sh
->lru
));
297 BUG_ON(atomic_read(&conf
->active_stripes
)==0);
298 if (test_bit(STRIPE_HANDLE
, &sh
->state
)) {
299 if (test_bit(STRIPE_DELAYED
, &sh
->state
) &&
300 !test_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
301 list_add_tail(&sh
->lru
, &conf
->delayed_list
);
302 else if (test_bit(STRIPE_BIT_DELAY
, &sh
->state
) &&
303 sh
->bm_seq
- conf
->seq_write
> 0)
304 list_add_tail(&sh
->lru
, &conf
->bitmap_list
);
306 clear_bit(STRIPE_DELAYED
, &sh
->state
);
307 clear_bit(STRIPE_BIT_DELAY
, &sh
->state
);
308 if (conf
->worker_cnt_per_group
== 0) {
309 list_add_tail(&sh
->lru
, &conf
->handle_list
);
311 raid5_wakeup_stripe_thread(sh
);
315 md_wakeup_thread(conf
->mddev
->thread
);
317 BUG_ON(stripe_operations_active(sh
));
318 if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
319 if (atomic_dec_return(&conf
->preread_active_stripes
)
321 md_wakeup_thread(conf
->mddev
->thread
);
322 atomic_dec(&conf
->active_stripes
);
323 if (!test_bit(STRIPE_EXPANDING
, &sh
->state
))
324 list_add_tail(&sh
->lru
, temp_inactive_list
);
328 static void __release_stripe(struct r5conf
*conf
, struct stripe_head
*sh
,
329 struct list_head
*temp_inactive_list
)
331 if (atomic_dec_and_test(&sh
->count
))
332 do_release_stripe(conf
, sh
, temp_inactive_list
);
336 * @hash could be NR_STRIPE_HASH_LOCKS, then we have a list of inactive_list
338 * Be careful: Only one task can add/delete stripes from temp_inactive_list at
339 * given time. Adding stripes only takes device lock, while deleting stripes
340 * only takes hash lock.
342 static void release_inactive_stripe_list(struct r5conf
*conf
,
343 struct list_head
*temp_inactive_list
,
347 bool do_wakeup
= false;
350 if (hash
== NR_STRIPE_HASH_LOCKS
) {
351 size
= NR_STRIPE_HASH_LOCKS
;
352 hash
= NR_STRIPE_HASH_LOCKS
- 1;
356 struct list_head
*list
= &temp_inactive_list
[size
- 1];
359 * We don't hold any lock here yet, get_active_stripe() might
360 * remove stripes from the list
362 if (!list_empty_careful(list
)) {
363 spin_lock_irqsave(conf
->hash_locks
+ hash
, flags
);
364 if (list_empty(conf
->inactive_list
+ hash
) &&
366 atomic_dec(&conf
->empty_inactive_list_nr
);
367 list_splice_tail_init(list
, conf
->inactive_list
+ hash
);
369 spin_unlock_irqrestore(conf
->hash_locks
+ hash
, flags
);
376 wake_up(&conf
->wait_for_stripe
);
377 if (conf
->retry_read_aligned
)
378 md_wakeup_thread(conf
->mddev
->thread
);
382 /* should hold conf->device_lock already */
383 static int release_stripe_list(struct r5conf
*conf
,
384 struct list_head
*temp_inactive_list
)
386 struct stripe_head
*sh
;
388 struct llist_node
*head
;
390 head
= llist_del_all(&conf
->released_stripes
);
391 head
= llist_reverse_order(head
);
395 sh
= llist_entry(head
, struct stripe_head
, release_list
);
396 head
= llist_next(head
);
397 /* sh could be readded after STRIPE_ON_RELEASE_LIST is cleard */
399 clear_bit(STRIPE_ON_RELEASE_LIST
, &sh
->state
);
401 * Don't worry the bit is set here, because if the bit is set
402 * again, the count is always > 1. This is true for
403 * STRIPE_ON_UNPLUG_LIST bit too.
405 hash
= sh
->hash_lock_index
;
406 __release_stripe(conf
, sh
, &temp_inactive_list
[hash
]);
413 static void release_stripe(struct stripe_head
*sh
)
415 struct r5conf
*conf
= sh
->raid_conf
;
417 struct list_head list
;
421 /* Avoid release_list until the last reference.
423 if (atomic_add_unless(&sh
->count
, -1, 1))
426 if (unlikely(!conf
->mddev
->thread
) ||
427 test_and_set_bit(STRIPE_ON_RELEASE_LIST
, &sh
->state
))
429 wakeup
= llist_add(&sh
->release_list
, &conf
->released_stripes
);
431 md_wakeup_thread(conf
->mddev
->thread
);
434 local_irq_save(flags
);
435 /* we are ok here if STRIPE_ON_RELEASE_LIST is set or not */
436 if (atomic_dec_and_lock(&sh
->count
, &conf
->device_lock
)) {
437 INIT_LIST_HEAD(&list
);
438 hash
= sh
->hash_lock_index
;
439 do_release_stripe(conf
, sh
, &list
);
440 spin_unlock(&conf
->device_lock
);
441 release_inactive_stripe_list(conf
, &list
, hash
);
443 local_irq_restore(flags
);
446 static inline void remove_hash(struct stripe_head
*sh
)
448 pr_debug("remove_hash(), stripe %llu\n",
449 (unsigned long long)sh
->sector
);
451 hlist_del_init(&sh
->hash
);
454 static inline void insert_hash(struct r5conf
*conf
, struct stripe_head
*sh
)
456 struct hlist_head
*hp
= stripe_hash(conf
, sh
->sector
);
458 pr_debug("insert_hash(), stripe %llu\n",
459 (unsigned long long)sh
->sector
);
461 hlist_add_head(&sh
->hash
, hp
);
464 /* find an idle stripe, make sure it is unhashed, and return it. */
465 static struct stripe_head
*get_free_stripe(struct r5conf
*conf
, int hash
)
467 struct stripe_head
*sh
= NULL
;
468 struct list_head
*first
;
470 if (list_empty(conf
->inactive_list
+ hash
))
472 first
= (conf
->inactive_list
+ hash
)->next
;
473 sh
= list_entry(first
, struct stripe_head
, lru
);
474 list_del_init(first
);
476 atomic_inc(&conf
->active_stripes
);
477 BUG_ON(hash
!= sh
->hash_lock_index
);
478 if (list_empty(conf
->inactive_list
+ hash
))
479 atomic_inc(&conf
->empty_inactive_list_nr
);
484 static void shrink_buffers(struct stripe_head
*sh
)
488 int num
= sh
->raid_conf
->pool_size
;
490 for (i
= 0; i
< num
; i
++) {
491 WARN_ON(sh
->dev
[i
].page
!= sh
->dev
[i
].orig_page
);
495 sh
->dev
[i
].page
= NULL
;
500 static int grow_buffers(struct stripe_head
*sh
, gfp_t gfp
)
503 int num
= sh
->raid_conf
->pool_size
;
505 for (i
= 0; i
< num
; i
++) {
508 if (!(page
= alloc_page(gfp
))) {
511 sh
->dev
[i
].page
= page
;
512 sh
->dev
[i
].orig_page
= page
;
517 static void raid5_build_block(struct stripe_head
*sh
, int i
, int previous
);
518 static void stripe_set_idx(sector_t stripe
, struct r5conf
*conf
, int previous
,
519 struct stripe_head
*sh
);
521 static void init_stripe(struct stripe_head
*sh
, sector_t sector
, int previous
)
523 struct r5conf
*conf
= sh
->raid_conf
;
526 BUG_ON(atomic_read(&sh
->count
) != 0);
527 BUG_ON(test_bit(STRIPE_HANDLE
, &sh
->state
));
528 BUG_ON(stripe_operations_active(sh
));
529 BUG_ON(sh
->batch_head
);
531 pr_debug("init_stripe called, stripe %llu\n",
532 (unsigned long long)sector
);
534 seq
= read_seqcount_begin(&conf
->gen_lock
);
535 sh
->generation
= conf
->generation
- previous
;
536 sh
->disks
= previous
? conf
->previous_raid_disks
: conf
->raid_disks
;
538 stripe_set_idx(sector
, conf
, previous
, sh
);
541 for (i
= sh
->disks
; i
--; ) {
542 struct r5dev
*dev
= &sh
->dev
[i
];
544 if (dev
->toread
|| dev
->read
|| dev
->towrite
|| dev
->written
||
545 test_bit(R5_LOCKED
, &dev
->flags
)) {
546 printk(KERN_ERR
"sector=%llx i=%d %p %p %p %p %d\n",
547 (unsigned long long)sh
->sector
, i
, dev
->toread
,
548 dev
->read
, dev
->towrite
, dev
->written
,
549 test_bit(R5_LOCKED
, &dev
->flags
));
553 raid5_build_block(sh
, i
, previous
);
555 if (read_seqcount_retry(&conf
->gen_lock
, seq
))
557 sh
->overwrite_disks
= 0;
558 insert_hash(conf
, sh
);
559 sh
->cpu
= smp_processor_id();
560 set_bit(STRIPE_BATCH_READY
, &sh
->state
);
563 static struct stripe_head
*__find_stripe(struct r5conf
*conf
, sector_t sector
,
566 struct stripe_head
*sh
;
568 pr_debug("__find_stripe, sector %llu\n", (unsigned long long)sector
);
569 hlist_for_each_entry(sh
, stripe_hash(conf
, sector
), hash
)
570 if (sh
->sector
== sector
&& sh
->generation
== generation
)
572 pr_debug("__stripe %llu not in cache\n", (unsigned long long)sector
);
577 * Need to check if array has failed when deciding whether to:
579 * - remove non-faulty devices
582 * This determination is simple when no reshape is happening.
583 * However if there is a reshape, we need to carefully check
584 * both the before and after sections.
585 * This is because some failed devices may only affect one
586 * of the two sections, and some non-in_sync devices may
587 * be insync in the section most affected by failed devices.
589 static int calc_degraded(struct r5conf
*conf
)
591 int degraded
, degraded2
;
596 for (i
= 0; i
< conf
->previous_raid_disks
; i
++) {
597 struct md_rdev
*rdev
= rcu_dereference(conf
->disks
[i
].rdev
);
598 if (rdev
&& test_bit(Faulty
, &rdev
->flags
))
599 rdev
= rcu_dereference(conf
->disks
[i
].replacement
);
600 if (!rdev
|| test_bit(Faulty
, &rdev
->flags
))
602 else if (test_bit(In_sync
, &rdev
->flags
))
605 /* not in-sync or faulty.
606 * If the reshape increases the number of devices,
607 * this is being recovered by the reshape, so
608 * this 'previous' section is not in_sync.
609 * If the number of devices is being reduced however,
610 * the device can only be part of the array if
611 * we are reverting a reshape, so this section will
614 if (conf
->raid_disks
>= conf
->previous_raid_disks
)
618 if (conf
->raid_disks
== conf
->previous_raid_disks
)
622 for (i
= 0; i
< conf
->raid_disks
; i
++) {
623 struct md_rdev
*rdev
= rcu_dereference(conf
->disks
[i
].rdev
);
624 if (rdev
&& test_bit(Faulty
, &rdev
->flags
))
625 rdev
= rcu_dereference(conf
->disks
[i
].replacement
);
626 if (!rdev
|| test_bit(Faulty
, &rdev
->flags
))
628 else if (test_bit(In_sync
, &rdev
->flags
))
631 /* not in-sync or faulty.
632 * If reshape increases the number of devices, this
633 * section has already been recovered, else it
634 * almost certainly hasn't.
636 if (conf
->raid_disks
<= conf
->previous_raid_disks
)
640 if (degraded2
> degraded
)
645 static int has_failed(struct r5conf
*conf
)
649 if (conf
->mddev
->reshape_position
== MaxSector
)
650 return conf
->mddev
->degraded
> conf
->max_degraded
;
652 degraded
= calc_degraded(conf
);
653 if (degraded
> conf
->max_degraded
)
658 static struct stripe_head
*
659 get_active_stripe(struct r5conf
*conf
, sector_t sector
,
660 int previous
, int noblock
, int noquiesce
)
662 struct stripe_head
*sh
;
663 int hash
= stripe_hash_locks_hash(sector
);
665 pr_debug("get_stripe, sector %llu\n", (unsigned long long)sector
);
667 spin_lock_irq(conf
->hash_locks
+ hash
);
670 wait_event_lock_irq(conf
->wait_for_stripe
,
671 conf
->quiesce
== 0 || noquiesce
,
672 *(conf
->hash_locks
+ hash
));
673 sh
= __find_stripe(conf
, sector
, conf
->generation
- previous
);
675 if (!test_bit(R5_INACTIVE_BLOCKED
, &conf
->cache_state
)) {
676 sh
= get_free_stripe(conf
, hash
);
677 if (!sh
&& llist_empty(&conf
->released_stripes
) &&
678 !test_bit(R5_DID_ALLOC
, &conf
->cache_state
))
679 set_bit(R5_ALLOC_MORE
,
682 if (noblock
&& sh
== NULL
)
685 set_bit(R5_INACTIVE_BLOCKED
,
688 conf
->wait_for_stripe
,
689 !list_empty(conf
->inactive_list
+ hash
) &&
690 (atomic_read(&conf
->active_stripes
)
691 < (conf
->max_nr_stripes
* 3 / 4)
692 || !test_bit(R5_INACTIVE_BLOCKED
,
693 &conf
->cache_state
)),
694 *(conf
->hash_locks
+ hash
));
695 clear_bit(R5_INACTIVE_BLOCKED
,
698 init_stripe(sh
, sector
, previous
);
699 atomic_inc(&sh
->count
);
701 } else if (!atomic_inc_not_zero(&sh
->count
)) {
702 spin_lock(&conf
->device_lock
);
703 if (!atomic_read(&sh
->count
)) {
704 if (!test_bit(STRIPE_HANDLE
, &sh
->state
))
705 atomic_inc(&conf
->active_stripes
);
706 BUG_ON(list_empty(&sh
->lru
) &&
707 !test_bit(STRIPE_EXPANDING
, &sh
->state
));
708 list_del_init(&sh
->lru
);
710 sh
->group
->stripes_cnt
--;
714 atomic_inc(&sh
->count
);
715 spin_unlock(&conf
->device_lock
);
717 } while (sh
== NULL
);
719 spin_unlock_irq(conf
->hash_locks
+ hash
);
723 static bool is_full_stripe_write(struct stripe_head
*sh
)
725 BUG_ON(sh
->overwrite_disks
> (sh
->disks
- sh
->raid_conf
->max_degraded
));
726 return sh
->overwrite_disks
== (sh
->disks
- sh
->raid_conf
->max_degraded
);
729 static void lock_two_stripes(struct stripe_head
*sh1
, struct stripe_head
*sh2
)
733 spin_lock(&sh2
->stripe_lock
);
734 spin_lock_nested(&sh1
->stripe_lock
, 1);
736 spin_lock(&sh1
->stripe_lock
);
737 spin_lock_nested(&sh2
->stripe_lock
, 1);
741 static void unlock_two_stripes(struct stripe_head
*sh1
, struct stripe_head
*sh2
)
743 spin_unlock(&sh1
->stripe_lock
);
744 spin_unlock(&sh2
->stripe_lock
);
748 /* Only freshly new full stripe normal write stripe can be added to a batch list */
749 static bool stripe_can_batch(struct stripe_head
*sh
)
751 return test_bit(STRIPE_BATCH_READY
, &sh
->state
) &&
752 is_full_stripe_write(sh
);
755 /* we only do back search */
756 static void stripe_add_to_batch_list(struct r5conf
*conf
, struct stripe_head
*sh
)
758 struct stripe_head
*head
;
759 sector_t head_sector
, tmp_sec
;
763 if (!stripe_can_batch(sh
))
765 /* Don't cross chunks, so stripe pd_idx/qd_idx is the same */
766 tmp_sec
= sh
->sector
;
767 if (!sector_div(tmp_sec
, conf
->chunk_sectors
))
769 head_sector
= sh
->sector
- STRIPE_SECTORS
;
771 hash
= stripe_hash_locks_hash(head_sector
);
772 spin_lock_irq(conf
->hash_locks
+ hash
);
773 head
= __find_stripe(conf
, head_sector
, conf
->generation
);
774 if (head
&& !atomic_inc_not_zero(&head
->count
)) {
775 spin_lock(&conf
->device_lock
);
776 if (!atomic_read(&head
->count
)) {
777 if (!test_bit(STRIPE_HANDLE
, &head
->state
))
778 atomic_inc(&conf
->active_stripes
);
779 BUG_ON(list_empty(&head
->lru
) &&
780 !test_bit(STRIPE_EXPANDING
, &head
->state
));
781 list_del_init(&head
->lru
);
783 head
->group
->stripes_cnt
--;
787 atomic_inc(&head
->count
);
788 spin_unlock(&conf
->device_lock
);
790 spin_unlock_irq(conf
->hash_locks
+ hash
);
794 if (!stripe_can_batch(head
))
797 lock_two_stripes(head
, sh
);
798 /* clear_batch_ready clear the flag */
799 if (!stripe_can_batch(head
) || !stripe_can_batch(sh
))
806 while (dd_idx
== sh
->pd_idx
|| dd_idx
== sh
->qd_idx
)
808 if (head
->dev
[dd_idx
].towrite
->bi_rw
!= sh
->dev
[dd_idx
].towrite
->bi_rw
)
811 if (head
->batch_head
) {
812 spin_lock(&head
->batch_head
->batch_lock
);
813 /* This batch list is already running */
814 if (!stripe_can_batch(head
)) {
815 spin_unlock(&head
->batch_head
->batch_lock
);
820 * at this point, head's BATCH_READY could be cleared, but we
821 * can still add the stripe to batch list
823 list_add(&sh
->batch_list
, &head
->batch_list
);
824 spin_unlock(&head
->batch_head
->batch_lock
);
826 sh
->batch_head
= head
->batch_head
;
828 head
->batch_head
= head
;
829 sh
->batch_head
= head
->batch_head
;
830 spin_lock(&head
->batch_lock
);
831 list_add_tail(&sh
->batch_list
, &head
->batch_list
);
832 spin_unlock(&head
->batch_lock
);
835 if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
836 if (atomic_dec_return(&conf
->preread_active_stripes
)
838 md_wakeup_thread(conf
->mddev
->thread
);
840 atomic_inc(&sh
->count
);
842 unlock_two_stripes(head
, sh
);
844 release_stripe(head
);
847 /* Determine if 'data_offset' or 'new_data_offset' should be used
848 * in this stripe_head.
850 static int use_new_offset(struct r5conf
*conf
, struct stripe_head
*sh
)
852 sector_t progress
= conf
->reshape_progress
;
853 /* Need a memory barrier to make sure we see the value
854 * of conf->generation, or ->data_offset that was set before
855 * reshape_progress was updated.
858 if (progress
== MaxSector
)
860 if (sh
->generation
== conf
->generation
- 1)
862 /* We are in a reshape, and this is a new-generation stripe,
863 * so use new_data_offset.
869 raid5_end_read_request(struct bio
*bi
, int error
);
871 raid5_end_write_request(struct bio
*bi
, int error
);
873 static void ops_run_io(struct stripe_head
*sh
, struct stripe_head_state
*s
)
875 struct r5conf
*conf
= sh
->raid_conf
;
876 int i
, disks
= sh
->disks
;
877 struct stripe_head
*head_sh
= sh
;
881 for (i
= disks
; i
--; ) {
883 int replace_only
= 0;
884 struct bio
*bi
, *rbi
;
885 struct md_rdev
*rdev
, *rrdev
= NULL
;
888 if (test_and_clear_bit(R5_Wantwrite
, &sh
->dev
[i
].flags
)) {
889 if (test_and_clear_bit(R5_WantFUA
, &sh
->dev
[i
].flags
))
893 if (test_bit(R5_Discard
, &sh
->dev
[i
].flags
))
895 } else if (test_and_clear_bit(R5_Wantread
, &sh
->dev
[i
].flags
))
897 else if (test_and_clear_bit(R5_WantReplace
,
898 &sh
->dev
[i
].flags
)) {
903 if (test_and_clear_bit(R5_SyncIO
, &sh
->dev
[i
].flags
))
907 bi
= &sh
->dev
[i
].req
;
908 rbi
= &sh
->dev
[i
].rreq
; /* For writing to replacement */
911 rrdev
= rcu_dereference(conf
->disks
[i
].replacement
);
912 smp_mb(); /* Ensure that if rrdev is NULL, rdev won't be */
913 rdev
= rcu_dereference(conf
->disks
[i
].rdev
);
922 /* We raced and saw duplicates */
925 if (test_bit(R5_ReadRepl
, &head_sh
->dev
[i
].flags
) && rrdev
)
930 if (rdev
&& test_bit(Faulty
, &rdev
->flags
))
933 atomic_inc(&rdev
->nr_pending
);
934 if (rrdev
&& test_bit(Faulty
, &rrdev
->flags
))
937 atomic_inc(&rrdev
->nr_pending
);
940 /* We have already checked bad blocks for reads. Now
941 * need to check for writes. We never accept write errors
942 * on the replacement, so we don't to check rrdev.
944 while ((rw
& WRITE
) && rdev
&&
945 test_bit(WriteErrorSeen
, &rdev
->flags
)) {
948 int bad
= is_badblock(rdev
, sh
->sector
, STRIPE_SECTORS
,
949 &first_bad
, &bad_sectors
);
954 set_bit(BlockedBadBlocks
, &rdev
->flags
);
955 if (!conf
->mddev
->external
&&
956 conf
->mddev
->flags
) {
957 /* It is very unlikely, but we might
958 * still need to write out the
959 * bad block log - better give it
961 md_check_recovery(conf
->mddev
);
964 * Because md_wait_for_blocked_rdev
965 * will dec nr_pending, we must
966 * increment it first.
968 atomic_inc(&rdev
->nr_pending
);
969 md_wait_for_blocked_rdev(rdev
, conf
->mddev
);
971 /* Acknowledged bad block - skip the write */
972 rdev_dec_pending(rdev
, conf
->mddev
);
978 if (s
->syncing
|| s
->expanding
|| s
->expanded
980 md_sync_acct(rdev
->bdev
, STRIPE_SECTORS
);
982 set_bit(STRIPE_IO_STARTED
, &sh
->state
);
985 bi
->bi_bdev
= rdev
->bdev
;
987 bi
->bi_end_io
= (rw
& WRITE
)
988 ? raid5_end_write_request
989 : raid5_end_read_request
;
992 pr_debug("%s: for %llu schedule op %ld on disc %d\n",
993 __func__
, (unsigned long long)sh
->sector
,
995 atomic_inc(&sh
->count
);
997 atomic_inc(&head_sh
->count
);
998 if (use_new_offset(conf
, sh
))
999 bi
->bi_iter
.bi_sector
= (sh
->sector
1000 + rdev
->new_data_offset
);
1002 bi
->bi_iter
.bi_sector
= (sh
->sector
1003 + rdev
->data_offset
);
1004 if (test_bit(R5_ReadNoMerge
, &head_sh
->dev
[i
].flags
))
1005 bi
->bi_rw
|= REQ_NOMERGE
;
1007 if (test_bit(R5_SkipCopy
, &sh
->dev
[i
].flags
))
1008 WARN_ON(test_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
));
1009 sh
->dev
[i
].vec
.bv_page
= sh
->dev
[i
].page
;
1011 bi
->bi_io_vec
[0].bv_len
= STRIPE_SIZE
;
1012 bi
->bi_io_vec
[0].bv_offset
= 0;
1013 bi
->bi_iter
.bi_size
= STRIPE_SIZE
;
1015 * If this is discard request, set bi_vcnt 0. We don't
1016 * want to confuse SCSI because SCSI will replace payload
1018 if (rw
& REQ_DISCARD
)
1021 set_bit(R5_DOUBLE_LOCKED
, &sh
->dev
[i
].flags
);
1023 if (conf
->mddev
->gendisk
)
1024 trace_block_bio_remap(bdev_get_queue(bi
->bi_bdev
),
1025 bi
, disk_devt(conf
->mddev
->gendisk
),
1027 generic_make_request(bi
);
1030 if (s
->syncing
|| s
->expanding
|| s
->expanded
1032 md_sync_acct(rrdev
->bdev
, STRIPE_SECTORS
);
1034 set_bit(STRIPE_IO_STARTED
, &sh
->state
);
1037 rbi
->bi_bdev
= rrdev
->bdev
;
1039 BUG_ON(!(rw
& WRITE
));
1040 rbi
->bi_end_io
= raid5_end_write_request
;
1041 rbi
->bi_private
= sh
;
1043 pr_debug("%s: for %llu schedule op %ld on "
1044 "replacement disc %d\n",
1045 __func__
, (unsigned long long)sh
->sector
,
1047 atomic_inc(&sh
->count
);
1049 atomic_inc(&head_sh
->count
);
1050 if (use_new_offset(conf
, sh
))
1051 rbi
->bi_iter
.bi_sector
= (sh
->sector
1052 + rrdev
->new_data_offset
);
1054 rbi
->bi_iter
.bi_sector
= (sh
->sector
1055 + rrdev
->data_offset
);
1056 if (test_bit(R5_SkipCopy
, &sh
->dev
[i
].flags
))
1057 WARN_ON(test_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
));
1058 sh
->dev
[i
].rvec
.bv_page
= sh
->dev
[i
].page
;
1060 rbi
->bi_io_vec
[0].bv_len
= STRIPE_SIZE
;
1061 rbi
->bi_io_vec
[0].bv_offset
= 0;
1062 rbi
->bi_iter
.bi_size
= STRIPE_SIZE
;
1064 * If this is discard request, set bi_vcnt 0. We don't
1065 * want to confuse SCSI because SCSI will replace payload
1067 if (rw
& REQ_DISCARD
)
1069 if (conf
->mddev
->gendisk
)
1070 trace_block_bio_remap(bdev_get_queue(rbi
->bi_bdev
),
1071 rbi
, disk_devt(conf
->mddev
->gendisk
),
1073 generic_make_request(rbi
);
1075 if (!rdev
&& !rrdev
) {
1077 set_bit(STRIPE_DEGRADED
, &sh
->state
);
1078 pr_debug("skip op %ld on disc %d for sector %llu\n",
1079 bi
->bi_rw
, i
, (unsigned long long)sh
->sector
);
1080 clear_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
1081 set_bit(STRIPE_HANDLE
, &sh
->state
);
1084 if (!head_sh
->batch_head
)
1086 sh
= list_first_entry(&sh
->batch_list
, struct stripe_head
,
1093 static struct dma_async_tx_descriptor
*
1094 async_copy_data(int frombio
, struct bio
*bio
, struct page
**page
,
1095 sector_t sector
, struct dma_async_tx_descriptor
*tx
,
1096 struct stripe_head
*sh
)
1099 struct bvec_iter iter
;
1100 struct page
*bio_page
;
1102 struct async_submit_ctl submit
;
1103 enum async_tx_flags flags
= 0;
1105 if (bio
->bi_iter
.bi_sector
>= sector
)
1106 page_offset
= (signed)(bio
->bi_iter
.bi_sector
- sector
) * 512;
1108 page_offset
= (signed)(sector
- bio
->bi_iter
.bi_sector
) * -512;
1111 flags
|= ASYNC_TX_FENCE
;
1112 init_async_submit(&submit
, flags
, tx
, NULL
, NULL
, NULL
);
1114 bio_for_each_segment(bvl
, bio
, iter
) {
1115 int len
= bvl
.bv_len
;
1119 if (page_offset
< 0) {
1120 b_offset
= -page_offset
;
1121 page_offset
+= b_offset
;
1125 if (len
> 0 && page_offset
+ len
> STRIPE_SIZE
)
1126 clen
= STRIPE_SIZE
- page_offset
;
1131 b_offset
+= bvl
.bv_offset
;
1132 bio_page
= bvl
.bv_page
;
1134 if (sh
->raid_conf
->skip_copy
&&
1135 b_offset
== 0 && page_offset
== 0 &&
1136 clen
== STRIPE_SIZE
)
1139 tx
= async_memcpy(*page
, bio_page
, page_offset
,
1140 b_offset
, clen
, &submit
);
1142 tx
= async_memcpy(bio_page
, *page
, b_offset
,
1143 page_offset
, clen
, &submit
);
1145 /* chain the operations */
1146 submit
.depend_tx
= tx
;
1148 if (clen
< len
) /* hit end of page */
1156 static void ops_complete_biofill(void *stripe_head_ref
)
1158 struct stripe_head
*sh
= stripe_head_ref
;
1159 struct bio
*return_bi
= NULL
;
1162 pr_debug("%s: stripe %llu\n", __func__
,
1163 (unsigned long long)sh
->sector
);
1165 /* clear completed biofills */
1166 for (i
= sh
->disks
; i
--; ) {
1167 struct r5dev
*dev
= &sh
->dev
[i
];
1169 /* acknowledge completion of a biofill operation */
1170 /* and check if we need to reply to a read request,
1171 * new R5_Wantfill requests are held off until
1172 * !STRIPE_BIOFILL_RUN
1174 if (test_and_clear_bit(R5_Wantfill
, &dev
->flags
)) {
1175 struct bio
*rbi
, *rbi2
;
1180 while (rbi
&& rbi
->bi_iter
.bi_sector
<
1181 dev
->sector
+ STRIPE_SECTORS
) {
1182 rbi2
= r5_next_bio(rbi
, dev
->sector
);
1183 if (!raid5_dec_bi_active_stripes(rbi
)) {
1184 rbi
->bi_next
= return_bi
;
1191 clear_bit(STRIPE_BIOFILL_RUN
, &sh
->state
);
1193 return_io(return_bi
);
1195 set_bit(STRIPE_HANDLE
, &sh
->state
);
1199 static void ops_run_biofill(struct stripe_head
*sh
)
1201 struct dma_async_tx_descriptor
*tx
= NULL
;
1202 struct async_submit_ctl submit
;
1205 BUG_ON(sh
->batch_head
);
1206 pr_debug("%s: stripe %llu\n", __func__
,
1207 (unsigned long long)sh
->sector
);
1209 for (i
= sh
->disks
; i
--; ) {
1210 struct r5dev
*dev
= &sh
->dev
[i
];
1211 if (test_bit(R5_Wantfill
, &dev
->flags
)) {
1213 spin_lock_irq(&sh
->stripe_lock
);
1214 dev
->read
= rbi
= dev
->toread
;
1216 spin_unlock_irq(&sh
->stripe_lock
);
1217 while (rbi
&& rbi
->bi_iter
.bi_sector
<
1218 dev
->sector
+ STRIPE_SECTORS
) {
1219 tx
= async_copy_data(0, rbi
, &dev
->page
,
1220 dev
->sector
, tx
, sh
);
1221 rbi
= r5_next_bio(rbi
, dev
->sector
);
1226 atomic_inc(&sh
->count
);
1227 init_async_submit(&submit
, ASYNC_TX_ACK
, tx
, ops_complete_biofill
, sh
, NULL
);
1228 async_trigger_callback(&submit
);
1231 static void mark_target_uptodate(struct stripe_head
*sh
, int target
)
1238 tgt
= &sh
->dev
[target
];
1239 set_bit(R5_UPTODATE
, &tgt
->flags
);
1240 BUG_ON(!test_bit(R5_Wantcompute
, &tgt
->flags
));
1241 clear_bit(R5_Wantcompute
, &tgt
->flags
);
1244 static void ops_complete_compute(void *stripe_head_ref
)
1246 struct stripe_head
*sh
= stripe_head_ref
;
1248 pr_debug("%s: stripe %llu\n", __func__
,
1249 (unsigned long long)sh
->sector
);
1251 /* mark the computed target(s) as uptodate */
1252 mark_target_uptodate(sh
, sh
->ops
.target
);
1253 mark_target_uptodate(sh
, sh
->ops
.target2
);
1255 clear_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
1256 if (sh
->check_state
== check_state_compute_run
)
1257 sh
->check_state
= check_state_compute_result
;
1258 set_bit(STRIPE_HANDLE
, &sh
->state
);
1262 /* return a pointer to the address conversion region of the scribble buffer */
1263 static addr_conv_t
*to_addr_conv(struct stripe_head
*sh
,
1264 struct raid5_percpu
*percpu
, int i
)
1268 addr
= flex_array_get(percpu
->scribble
, i
);
1269 return addr
+ sizeof(struct page
*) * (sh
->disks
+ 2);
1272 /* return a pointer to the address conversion region of the scribble buffer */
1273 static struct page
**to_addr_page(struct raid5_percpu
*percpu
, int i
)
1277 addr
= flex_array_get(percpu
->scribble
, i
);
1281 static struct dma_async_tx_descriptor
*
1282 ops_run_compute5(struct stripe_head
*sh
, struct raid5_percpu
*percpu
)
1284 int disks
= sh
->disks
;
1285 struct page
**xor_srcs
= to_addr_page(percpu
, 0);
1286 int target
= sh
->ops
.target
;
1287 struct r5dev
*tgt
= &sh
->dev
[target
];
1288 struct page
*xor_dest
= tgt
->page
;
1290 struct dma_async_tx_descriptor
*tx
;
1291 struct async_submit_ctl submit
;
1294 BUG_ON(sh
->batch_head
);
1296 pr_debug("%s: stripe %llu block: %d\n",
1297 __func__
, (unsigned long long)sh
->sector
, target
);
1298 BUG_ON(!test_bit(R5_Wantcompute
, &tgt
->flags
));
1300 for (i
= disks
; i
--; )
1302 xor_srcs
[count
++] = sh
->dev
[i
].page
;
1304 atomic_inc(&sh
->count
);
1306 init_async_submit(&submit
, ASYNC_TX_FENCE
|ASYNC_TX_XOR_ZERO_DST
, NULL
,
1307 ops_complete_compute
, sh
, to_addr_conv(sh
, percpu
, 0));
1308 if (unlikely(count
== 1))
1309 tx
= async_memcpy(xor_dest
, xor_srcs
[0], 0, 0, STRIPE_SIZE
, &submit
);
1311 tx
= async_xor(xor_dest
, xor_srcs
, 0, count
, STRIPE_SIZE
, &submit
);
1316 /* set_syndrome_sources - populate source buffers for gen_syndrome
1317 * @srcs - (struct page *) array of size sh->disks
1318 * @sh - stripe_head to parse
1320 * Populates srcs in proper layout order for the stripe and returns the
1321 * 'count' of sources to be used in a call to async_gen_syndrome. The P
1322 * destination buffer is recorded in srcs[count] and the Q destination
1323 * is recorded in srcs[count+1]].
1325 static int set_syndrome_sources(struct page
**srcs
,
1326 struct stripe_head
*sh
,
1329 int disks
= sh
->disks
;
1330 int syndrome_disks
= sh
->ddf_layout
? disks
: (disks
- 2);
1331 int d0_idx
= raid6_d0(sh
);
1335 for (i
= 0; i
< disks
; i
++)
1341 int slot
= raid6_idx_to_slot(i
, sh
, &count
, syndrome_disks
);
1342 struct r5dev
*dev
= &sh
->dev
[i
];
1344 if (i
== sh
->qd_idx
|| i
== sh
->pd_idx
||
1345 (srctype
== SYNDROME_SRC_ALL
) ||
1346 (srctype
== SYNDROME_SRC_WANT_DRAIN
&&
1347 test_bit(R5_Wantdrain
, &dev
->flags
)) ||
1348 (srctype
== SYNDROME_SRC_WRITTEN
&&
1350 srcs
[slot
] = sh
->dev
[i
].page
;
1351 i
= raid6_next_disk(i
, disks
);
1352 } while (i
!= d0_idx
);
1354 return syndrome_disks
;
1357 static struct dma_async_tx_descriptor
*
1358 ops_run_compute6_1(struct stripe_head
*sh
, struct raid5_percpu
*percpu
)
1360 int disks
= sh
->disks
;
1361 struct page
**blocks
= to_addr_page(percpu
, 0);
1363 int qd_idx
= sh
->qd_idx
;
1364 struct dma_async_tx_descriptor
*tx
;
1365 struct async_submit_ctl submit
;
1371 BUG_ON(sh
->batch_head
);
1372 if (sh
->ops
.target
< 0)
1373 target
= sh
->ops
.target2
;
1374 else if (sh
->ops
.target2
< 0)
1375 target
= sh
->ops
.target
;
1377 /* we should only have one valid target */
1380 pr_debug("%s: stripe %llu block: %d\n",
1381 __func__
, (unsigned long long)sh
->sector
, target
);
1383 tgt
= &sh
->dev
[target
];
1384 BUG_ON(!test_bit(R5_Wantcompute
, &tgt
->flags
));
1387 atomic_inc(&sh
->count
);
1389 if (target
== qd_idx
) {
1390 count
= set_syndrome_sources(blocks
, sh
, SYNDROME_SRC_ALL
);
1391 blocks
[count
] = NULL
; /* regenerating p is not necessary */
1392 BUG_ON(blocks
[count
+1] != dest
); /* q should already be set */
1393 init_async_submit(&submit
, ASYNC_TX_FENCE
, NULL
,
1394 ops_complete_compute
, sh
,
1395 to_addr_conv(sh
, percpu
, 0));
1396 tx
= async_gen_syndrome(blocks
, 0, count
+2, STRIPE_SIZE
, &submit
);
1398 /* Compute any data- or p-drive using XOR */
1400 for (i
= disks
; i
-- ; ) {
1401 if (i
== target
|| i
== qd_idx
)
1403 blocks
[count
++] = sh
->dev
[i
].page
;
1406 init_async_submit(&submit
, ASYNC_TX_FENCE
|ASYNC_TX_XOR_ZERO_DST
,
1407 NULL
, ops_complete_compute
, sh
,
1408 to_addr_conv(sh
, percpu
, 0));
1409 tx
= async_xor(dest
, blocks
, 0, count
, STRIPE_SIZE
, &submit
);
1415 static struct dma_async_tx_descriptor
*
1416 ops_run_compute6_2(struct stripe_head
*sh
, struct raid5_percpu
*percpu
)
1418 int i
, count
, disks
= sh
->disks
;
1419 int syndrome_disks
= sh
->ddf_layout
? disks
: disks
-2;
1420 int d0_idx
= raid6_d0(sh
);
1421 int faila
= -1, failb
= -1;
1422 int target
= sh
->ops
.target
;
1423 int target2
= sh
->ops
.target2
;
1424 struct r5dev
*tgt
= &sh
->dev
[target
];
1425 struct r5dev
*tgt2
= &sh
->dev
[target2
];
1426 struct dma_async_tx_descriptor
*tx
;
1427 struct page
**blocks
= to_addr_page(percpu
, 0);
1428 struct async_submit_ctl submit
;
1430 BUG_ON(sh
->batch_head
);
1431 pr_debug("%s: stripe %llu block1: %d block2: %d\n",
1432 __func__
, (unsigned long long)sh
->sector
, target
, target2
);
1433 BUG_ON(target
< 0 || target2
< 0);
1434 BUG_ON(!test_bit(R5_Wantcompute
, &tgt
->flags
));
1435 BUG_ON(!test_bit(R5_Wantcompute
, &tgt2
->flags
));
1437 /* we need to open-code set_syndrome_sources to handle the
1438 * slot number conversion for 'faila' and 'failb'
1440 for (i
= 0; i
< disks
; i
++)
1445 int slot
= raid6_idx_to_slot(i
, sh
, &count
, syndrome_disks
);
1447 blocks
[slot
] = sh
->dev
[i
].page
;
1453 i
= raid6_next_disk(i
, disks
);
1454 } while (i
!= d0_idx
);
1456 BUG_ON(faila
== failb
);
1459 pr_debug("%s: stripe: %llu faila: %d failb: %d\n",
1460 __func__
, (unsigned long long)sh
->sector
, faila
, failb
);
1462 atomic_inc(&sh
->count
);
1464 if (failb
== syndrome_disks
+1) {
1465 /* Q disk is one of the missing disks */
1466 if (faila
== syndrome_disks
) {
1467 /* Missing P+Q, just recompute */
1468 init_async_submit(&submit
, ASYNC_TX_FENCE
, NULL
,
1469 ops_complete_compute
, sh
,
1470 to_addr_conv(sh
, percpu
, 0));
1471 return async_gen_syndrome(blocks
, 0, syndrome_disks
+2,
1472 STRIPE_SIZE
, &submit
);
1476 int qd_idx
= sh
->qd_idx
;
1478 /* Missing D+Q: recompute D from P, then recompute Q */
1479 if (target
== qd_idx
)
1480 data_target
= target2
;
1482 data_target
= target
;
1485 for (i
= disks
; i
-- ; ) {
1486 if (i
== data_target
|| i
== qd_idx
)
1488 blocks
[count
++] = sh
->dev
[i
].page
;
1490 dest
= sh
->dev
[data_target
].page
;
1491 init_async_submit(&submit
,
1492 ASYNC_TX_FENCE
|ASYNC_TX_XOR_ZERO_DST
,
1494 to_addr_conv(sh
, percpu
, 0));
1495 tx
= async_xor(dest
, blocks
, 0, count
, STRIPE_SIZE
,
1498 count
= set_syndrome_sources(blocks
, sh
, SYNDROME_SRC_ALL
);
1499 init_async_submit(&submit
, ASYNC_TX_FENCE
, tx
,
1500 ops_complete_compute
, sh
,
1501 to_addr_conv(sh
, percpu
, 0));
1502 return async_gen_syndrome(blocks
, 0, count
+2,
1503 STRIPE_SIZE
, &submit
);
1506 init_async_submit(&submit
, ASYNC_TX_FENCE
, NULL
,
1507 ops_complete_compute
, sh
,
1508 to_addr_conv(sh
, percpu
, 0));
1509 if (failb
== syndrome_disks
) {
1510 /* We're missing D+P. */
1511 return async_raid6_datap_recov(syndrome_disks
+2,
1515 /* We're missing D+D. */
1516 return async_raid6_2data_recov(syndrome_disks
+2,
1517 STRIPE_SIZE
, faila
, failb
,
1523 static void ops_complete_prexor(void *stripe_head_ref
)
1525 struct stripe_head
*sh
= stripe_head_ref
;
1527 pr_debug("%s: stripe %llu\n", __func__
,
1528 (unsigned long long)sh
->sector
);
1531 static struct dma_async_tx_descriptor
*
1532 ops_run_prexor5(struct stripe_head
*sh
, struct raid5_percpu
*percpu
,
1533 struct dma_async_tx_descriptor
*tx
)
1535 int disks
= sh
->disks
;
1536 struct page
**xor_srcs
= to_addr_page(percpu
, 0);
1537 int count
= 0, pd_idx
= sh
->pd_idx
, i
;
1538 struct async_submit_ctl submit
;
1540 /* existing parity data subtracted */
1541 struct page
*xor_dest
= xor_srcs
[count
++] = sh
->dev
[pd_idx
].page
;
1543 BUG_ON(sh
->batch_head
);
1544 pr_debug("%s: stripe %llu\n", __func__
,
1545 (unsigned long long)sh
->sector
);
1547 for (i
= disks
; i
--; ) {
1548 struct r5dev
*dev
= &sh
->dev
[i
];
1549 /* Only process blocks that are known to be uptodate */
1550 if (test_bit(R5_Wantdrain
, &dev
->flags
))
1551 xor_srcs
[count
++] = dev
->page
;
1554 init_async_submit(&submit
, ASYNC_TX_FENCE
|ASYNC_TX_XOR_DROP_DST
, tx
,
1555 ops_complete_prexor
, sh
, to_addr_conv(sh
, percpu
, 0));
1556 tx
= async_xor(xor_dest
, xor_srcs
, 0, count
, STRIPE_SIZE
, &submit
);
1561 static struct dma_async_tx_descriptor
*
1562 ops_run_prexor6(struct stripe_head
*sh
, struct raid5_percpu
*percpu
,
1563 struct dma_async_tx_descriptor
*tx
)
1565 struct page
**blocks
= to_addr_page(percpu
, 0);
1567 struct async_submit_ctl submit
;
1569 pr_debug("%s: stripe %llu\n", __func__
,
1570 (unsigned long long)sh
->sector
);
1572 count
= set_syndrome_sources(blocks
, sh
, SYNDROME_SRC_WANT_DRAIN
);
1574 init_async_submit(&submit
, ASYNC_TX_FENCE
|ASYNC_TX_PQ_XOR_DST
, tx
,
1575 ops_complete_prexor
, sh
, to_addr_conv(sh
, percpu
, 0));
1576 tx
= async_gen_syndrome(blocks
, 0, count
+2, STRIPE_SIZE
, &submit
);
1581 static struct dma_async_tx_descriptor
*
1582 ops_run_biodrain(struct stripe_head
*sh
, struct dma_async_tx_descriptor
*tx
)
1584 int disks
= sh
->disks
;
1586 struct stripe_head
*head_sh
= sh
;
1588 pr_debug("%s: stripe %llu\n", __func__
,
1589 (unsigned long long)sh
->sector
);
1591 for (i
= disks
; i
--; ) {
1596 if (test_and_clear_bit(R5_Wantdrain
, &head_sh
->dev
[i
].flags
)) {
1601 spin_lock_irq(&sh
->stripe_lock
);
1602 chosen
= dev
->towrite
;
1603 dev
->towrite
= NULL
;
1604 sh
->overwrite_disks
= 0;
1605 BUG_ON(dev
->written
);
1606 wbi
= dev
->written
= chosen
;
1607 spin_unlock_irq(&sh
->stripe_lock
);
1608 WARN_ON(dev
->page
!= dev
->orig_page
);
1610 while (wbi
&& wbi
->bi_iter
.bi_sector
<
1611 dev
->sector
+ STRIPE_SECTORS
) {
1612 if (wbi
->bi_rw
& REQ_FUA
)
1613 set_bit(R5_WantFUA
, &dev
->flags
);
1614 if (wbi
->bi_rw
& REQ_SYNC
)
1615 set_bit(R5_SyncIO
, &dev
->flags
);
1616 if (wbi
->bi_rw
& REQ_DISCARD
)
1617 set_bit(R5_Discard
, &dev
->flags
);
1619 tx
= async_copy_data(1, wbi
, &dev
->page
,
1620 dev
->sector
, tx
, sh
);
1621 if (dev
->page
!= dev
->orig_page
) {
1622 set_bit(R5_SkipCopy
, &dev
->flags
);
1623 clear_bit(R5_UPTODATE
, &dev
->flags
);
1624 clear_bit(R5_OVERWRITE
, &dev
->flags
);
1627 wbi
= r5_next_bio(wbi
, dev
->sector
);
1630 if (head_sh
->batch_head
) {
1631 sh
= list_first_entry(&sh
->batch_list
,
1644 static void ops_complete_reconstruct(void *stripe_head_ref
)
1646 struct stripe_head
*sh
= stripe_head_ref
;
1647 int disks
= sh
->disks
;
1648 int pd_idx
= sh
->pd_idx
;
1649 int qd_idx
= sh
->qd_idx
;
1651 bool fua
= false, sync
= false, discard
= false;
1653 pr_debug("%s: stripe %llu\n", __func__
,
1654 (unsigned long long)sh
->sector
);
1656 for (i
= disks
; i
--; ) {
1657 fua
|= test_bit(R5_WantFUA
, &sh
->dev
[i
].flags
);
1658 sync
|= test_bit(R5_SyncIO
, &sh
->dev
[i
].flags
);
1659 discard
|= test_bit(R5_Discard
, &sh
->dev
[i
].flags
);
1662 for (i
= disks
; i
--; ) {
1663 struct r5dev
*dev
= &sh
->dev
[i
];
1665 if (dev
->written
|| i
== pd_idx
|| i
== qd_idx
) {
1666 if (!discard
&& !test_bit(R5_SkipCopy
, &dev
->flags
))
1667 set_bit(R5_UPTODATE
, &dev
->flags
);
1669 set_bit(R5_WantFUA
, &dev
->flags
);
1671 set_bit(R5_SyncIO
, &dev
->flags
);
1675 if (sh
->reconstruct_state
== reconstruct_state_drain_run
)
1676 sh
->reconstruct_state
= reconstruct_state_drain_result
;
1677 else if (sh
->reconstruct_state
== reconstruct_state_prexor_drain_run
)
1678 sh
->reconstruct_state
= reconstruct_state_prexor_drain_result
;
1680 BUG_ON(sh
->reconstruct_state
!= reconstruct_state_run
);
1681 sh
->reconstruct_state
= reconstruct_state_result
;
1684 set_bit(STRIPE_HANDLE
, &sh
->state
);
1689 ops_run_reconstruct5(struct stripe_head
*sh
, struct raid5_percpu
*percpu
,
1690 struct dma_async_tx_descriptor
*tx
)
1692 int disks
= sh
->disks
;
1693 struct page
**xor_srcs
;
1694 struct async_submit_ctl submit
;
1695 int count
, pd_idx
= sh
->pd_idx
, i
;
1696 struct page
*xor_dest
;
1698 unsigned long flags
;
1700 struct stripe_head
*head_sh
= sh
;
1703 pr_debug("%s: stripe %llu\n", __func__
,
1704 (unsigned long long)sh
->sector
);
1706 for (i
= 0; i
< sh
->disks
; i
++) {
1709 if (!test_bit(R5_Discard
, &sh
->dev
[i
].flags
))
1712 if (i
>= sh
->disks
) {
1713 atomic_inc(&sh
->count
);
1714 set_bit(R5_Discard
, &sh
->dev
[pd_idx
].flags
);
1715 ops_complete_reconstruct(sh
);
1720 xor_srcs
= to_addr_page(percpu
, j
);
1721 /* check if prexor is active which means only process blocks
1722 * that are part of a read-modify-write (written)
1724 if (head_sh
->reconstruct_state
== reconstruct_state_prexor_drain_run
) {
1726 xor_dest
= xor_srcs
[count
++] = sh
->dev
[pd_idx
].page
;
1727 for (i
= disks
; i
--; ) {
1728 struct r5dev
*dev
= &sh
->dev
[i
];
1729 if (head_sh
->dev
[i
].written
)
1730 xor_srcs
[count
++] = dev
->page
;
1733 xor_dest
= sh
->dev
[pd_idx
].page
;
1734 for (i
= disks
; i
--; ) {
1735 struct r5dev
*dev
= &sh
->dev
[i
];
1737 xor_srcs
[count
++] = dev
->page
;
1741 /* 1/ if we prexor'd then the dest is reused as a source
1742 * 2/ if we did not prexor then we are redoing the parity
1743 * set ASYNC_TX_XOR_DROP_DST and ASYNC_TX_XOR_ZERO_DST
1744 * for the synchronous xor case
1746 last_stripe
= !head_sh
->batch_head
||
1747 list_first_entry(&sh
->batch_list
,
1748 struct stripe_head
, batch_list
) == head_sh
;
1750 flags
= ASYNC_TX_ACK
|
1751 (prexor
? ASYNC_TX_XOR_DROP_DST
: ASYNC_TX_XOR_ZERO_DST
);
1753 atomic_inc(&head_sh
->count
);
1754 init_async_submit(&submit
, flags
, tx
, ops_complete_reconstruct
, head_sh
,
1755 to_addr_conv(sh
, percpu
, j
));
1757 flags
= prexor
? ASYNC_TX_XOR_DROP_DST
: ASYNC_TX_XOR_ZERO_DST
;
1758 init_async_submit(&submit
, flags
, tx
, NULL
, NULL
,
1759 to_addr_conv(sh
, percpu
, j
));
1762 if (unlikely(count
== 1))
1763 tx
= async_memcpy(xor_dest
, xor_srcs
[0], 0, 0, STRIPE_SIZE
, &submit
);
1765 tx
= async_xor(xor_dest
, xor_srcs
, 0, count
, STRIPE_SIZE
, &submit
);
1768 sh
= list_first_entry(&sh
->batch_list
, struct stripe_head
,
1775 ops_run_reconstruct6(struct stripe_head
*sh
, struct raid5_percpu
*percpu
,
1776 struct dma_async_tx_descriptor
*tx
)
1778 struct async_submit_ctl submit
;
1779 struct page
**blocks
;
1780 int count
, i
, j
= 0;
1781 struct stripe_head
*head_sh
= sh
;
1784 unsigned long txflags
;
1786 pr_debug("%s: stripe %llu\n", __func__
, (unsigned long long)sh
->sector
);
1788 for (i
= 0; i
< sh
->disks
; i
++) {
1789 if (sh
->pd_idx
== i
|| sh
->qd_idx
== i
)
1791 if (!test_bit(R5_Discard
, &sh
->dev
[i
].flags
))
1794 if (i
>= sh
->disks
) {
1795 atomic_inc(&sh
->count
);
1796 set_bit(R5_Discard
, &sh
->dev
[sh
->pd_idx
].flags
);
1797 set_bit(R5_Discard
, &sh
->dev
[sh
->qd_idx
].flags
);
1798 ops_complete_reconstruct(sh
);
1803 blocks
= to_addr_page(percpu
, j
);
1805 if (sh
->reconstruct_state
== reconstruct_state_prexor_drain_run
) {
1806 synflags
= SYNDROME_SRC_WRITTEN
;
1807 txflags
= ASYNC_TX_ACK
| ASYNC_TX_PQ_XOR_DST
;
1809 synflags
= SYNDROME_SRC_ALL
;
1810 txflags
= ASYNC_TX_ACK
;
1813 count
= set_syndrome_sources(blocks
, sh
, synflags
);
1814 last_stripe
= !head_sh
->batch_head
||
1815 list_first_entry(&sh
->batch_list
,
1816 struct stripe_head
, batch_list
) == head_sh
;
1819 atomic_inc(&head_sh
->count
);
1820 init_async_submit(&submit
, txflags
, tx
, ops_complete_reconstruct
,
1821 head_sh
, to_addr_conv(sh
, percpu
, j
));
1823 init_async_submit(&submit
, 0, tx
, NULL
, NULL
,
1824 to_addr_conv(sh
, percpu
, j
));
1825 async_gen_syndrome(blocks
, 0, count
+2, STRIPE_SIZE
, &submit
);
1828 sh
= list_first_entry(&sh
->batch_list
, struct stripe_head
,
1834 static void ops_complete_check(void *stripe_head_ref
)
1836 struct stripe_head
*sh
= stripe_head_ref
;
1838 pr_debug("%s: stripe %llu\n", __func__
,
1839 (unsigned long long)sh
->sector
);
1841 sh
->check_state
= check_state_check_result
;
1842 set_bit(STRIPE_HANDLE
, &sh
->state
);
1846 static void ops_run_check_p(struct stripe_head
*sh
, struct raid5_percpu
*percpu
)
1848 int disks
= sh
->disks
;
1849 int pd_idx
= sh
->pd_idx
;
1850 int qd_idx
= sh
->qd_idx
;
1851 struct page
*xor_dest
;
1852 struct page
**xor_srcs
= to_addr_page(percpu
, 0);
1853 struct dma_async_tx_descriptor
*tx
;
1854 struct async_submit_ctl submit
;
1858 pr_debug("%s: stripe %llu\n", __func__
,
1859 (unsigned long long)sh
->sector
);
1861 BUG_ON(sh
->batch_head
);
1863 xor_dest
= sh
->dev
[pd_idx
].page
;
1864 xor_srcs
[count
++] = xor_dest
;
1865 for (i
= disks
; i
--; ) {
1866 if (i
== pd_idx
|| i
== qd_idx
)
1868 xor_srcs
[count
++] = sh
->dev
[i
].page
;
1871 init_async_submit(&submit
, 0, NULL
, NULL
, NULL
,
1872 to_addr_conv(sh
, percpu
, 0));
1873 tx
= async_xor_val(xor_dest
, xor_srcs
, 0, count
, STRIPE_SIZE
,
1874 &sh
->ops
.zero_sum_result
, &submit
);
1876 atomic_inc(&sh
->count
);
1877 init_async_submit(&submit
, ASYNC_TX_ACK
, tx
, ops_complete_check
, sh
, NULL
);
1878 tx
= async_trigger_callback(&submit
);
1881 static void ops_run_check_pq(struct stripe_head
*sh
, struct raid5_percpu
*percpu
, int checkp
)
1883 struct page
**srcs
= to_addr_page(percpu
, 0);
1884 struct async_submit_ctl submit
;
1887 pr_debug("%s: stripe %llu checkp: %d\n", __func__
,
1888 (unsigned long long)sh
->sector
, checkp
);
1890 BUG_ON(sh
->batch_head
);
1891 count
= set_syndrome_sources(srcs
, sh
, SYNDROME_SRC_ALL
);
1895 atomic_inc(&sh
->count
);
1896 init_async_submit(&submit
, ASYNC_TX_ACK
, NULL
, ops_complete_check
,
1897 sh
, to_addr_conv(sh
, percpu
, 0));
1898 async_syndrome_val(srcs
, 0, count
+2, STRIPE_SIZE
,
1899 &sh
->ops
.zero_sum_result
, percpu
->spare_page
, &submit
);
1902 static void raid_run_ops(struct stripe_head
*sh
, unsigned long ops_request
)
1904 int overlap_clear
= 0, i
, disks
= sh
->disks
;
1905 struct dma_async_tx_descriptor
*tx
= NULL
;
1906 struct r5conf
*conf
= sh
->raid_conf
;
1907 int level
= conf
->level
;
1908 struct raid5_percpu
*percpu
;
1912 percpu
= per_cpu_ptr(conf
->percpu
, cpu
);
1913 if (test_bit(STRIPE_OP_BIOFILL
, &ops_request
)) {
1914 ops_run_biofill(sh
);
1918 if (test_bit(STRIPE_OP_COMPUTE_BLK
, &ops_request
)) {
1920 tx
= ops_run_compute5(sh
, percpu
);
1922 if (sh
->ops
.target2
< 0 || sh
->ops
.target
< 0)
1923 tx
= ops_run_compute6_1(sh
, percpu
);
1925 tx
= ops_run_compute6_2(sh
, percpu
);
1927 /* terminate the chain if reconstruct is not set to be run */
1928 if (tx
&& !test_bit(STRIPE_OP_RECONSTRUCT
, &ops_request
))
1932 if (test_bit(STRIPE_OP_PREXOR
, &ops_request
)) {
1934 tx
= ops_run_prexor5(sh
, percpu
, tx
);
1936 tx
= ops_run_prexor6(sh
, percpu
, tx
);
1939 if (test_bit(STRIPE_OP_BIODRAIN
, &ops_request
)) {
1940 tx
= ops_run_biodrain(sh
, tx
);
1944 if (test_bit(STRIPE_OP_RECONSTRUCT
, &ops_request
)) {
1946 ops_run_reconstruct5(sh
, percpu
, tx
);
1948 ops_run_reconstruct6(sh
, percpu
, tx
);
1951 if (test_bit(STRIPE_OP_CHECK
, &ops_request
)) {
1952 if (sh
->check_state
== check_state_run
)
1953 ops_run_check_p(sh
, percpu
);
1954 else if (sh
->check_state
== check_state_run_q
)
1955 ops_run_check_pq(sh
, percpu
, 0);
1956 else if (sh
->check_state
== check_state_run_pq
)
1957 ops_run_check_pq(sh
, percpu
, 1);
1962 if (overlap_clear
&& !sh
->batch_head
)
1963 for (i
= disks
; i
--; ) {
1964 struct r5dev
*dev
= &sh
->dev
[i
];
1965 if (test_and_clear_bit(R5_Overlap
, &dev
->flags
))
1966 wake_up(&sh
->raid_conf
->wait_for_overlap
);
1971 static struct stripe_head
*alloc_stripe(struct kmem_cache
*sc
, gfp_t gfp
)
1973 struct stripe_head
*sh
;
1975 sh
= kmem_cache_zalloc(sc
, gfp
);
1977 spin_lock_init(&sh
->stripe_lock
);
1978 spin_lock_init(&sh
->batch_lock
);
1979 INIT_LIST_HEAD(&sh
->batch_list
);
1980 INIT_LIST_HEAD(&sh
->lru
);
1981 atomic_set(&sh
->count
, 1);
1985 static int grow_one_stripe(struct r5conf
*conf
, gfp_t gfp
)
1987 struct stripe_head
*sh
;
1989 sh
= alloc_stripe(conf
->slab_cache
, gfp
);
1993 sh
->raid_conf
= conf
;
1995 if (grow_buffers(sh
, gfp
)) {
1997 kmem_cache_free(conf
->slab_cache
, sh
);
2000 sh
->hash_lock_index
=
2001 conf
->max_nr_stripes
% NR_STRIPE_HASH_LOCKS
;
2002 /* we just created an active stripe so... */
2003 atomic_inc(&conf
->active_stripes
);
2006 conf
->max_nr_stripes
++;
2010 static int grow_stripes(struct r5conf
*conf
, int num
)
2012 struct kmem_cache
*sc
;
2013 int devs
= max(conf
->raid_disks
, conf
->previous_raid_disks
);
2015 if (conf
->mddev
->gendisk
)
2016 sprintf(conf
->cache_name
[0],
2017 "raid%d-%s", conf
->level
, mdname(conf
->mddev
));
2019 sprintf(conf
->cache_name
[0],
2020 "raid%d-%p", conf
->level
, conf
->mddev
);
2021 sprintf(conf
->cache_name
[1], "%s-alt", conf
->cache_name
[0]);
2023 conf
->active_name
= 0;
2024 sc
= kmem_cache_create(conf
->cache_name
[conf
->active_name
],
2025 sizeof(struct stripe_head
)+(devs
-1)*sizeof(struct r5dev
),
2029 conf
->slab_cache
= sc
;
2030 conf
->pool_size
= devs
;
2032 if (!grow_one_stripe(conf
, GFP_KERNEL
))
2039 * scribble_len - return the required size of the scribble region
2040 * @num - total number of disks in the array
2042 * The size must be enough to contain:
2043 * 1/ a struct page pointer for each device in the array +2
2044 * 2/ room to convert each entry in (1) to its corresponding dma
2045 * (dma_map_page()) or page (page_address()) address.
2047 * Note: the +2 is for the destination buffers of the ddf/raid6 case where we
2048 * calculate over all devices (not just the data blocks), using zeros in place
2049 * of the P and Q blocks.
2051 static struct flex_array
*scribble_alloc(int num
, int cnt
, gfp_t flags
)
2053 struct flex_array
*ret
;
2056 len
= sizeof(struct page
*) * (num
+2) + sizeof(addr_conv_t
) * (num
+2);
2057 ret
= flex_array_alloc(len
, cnt
, flags
);
2060 /* always prealloc all elements, so no locking is required */
2061 if (flex_array_prealloc(ret
, 0, cnt
, flags
)) {
2062 flex_array_free(ret
);
2068 static int resize_chunks(struct r5conf
*conf
, int new_disks
, int new_sectors
)
2073 mddev_suspend(conf
->mddev
);
2075 for_each_present_cpu(cpu
) {
2076 struct raid5_percpu
*percpu
;
2077 struct flex_array
*scribble
;
2079 percpu
= per_cpu_ptr(conf
->percpu
, cpu
);
2080 scribble
= scribble_alloc(new_disks
,
2081 new_sectors
/ STRIPE_SECTORS
,
2085 flex_array_free(percpu
->scribble
);
2086 percpu
->scribble
= scribble
;
2093 mddev_resume(conf
->mddev
);
2097 static int resize_stripes(struct r5conf
*conf
, int newsize
)
2099 /* Make all the stripes able to hold 'newsize' devices.
2100 * New slots in each stripe get 'page' set to a new page.
2102 * This happens in stages:
2103 * 1/ create a new kmem_cache and allocate the required number of
2105 * 2/ gather all the old stripe_heads and transfer the pages across
2106 * to the new stripe_heads. This will have the side effect of
2107 * freezing the array as once all stripe_heads have been collected,
2108 * no IO will be possible. Old stripe heads are freed once their
2109 * pages have been transferred over, and the old kmem_cache is
2110 * freed when all stripes are done.
2111 * 3/ reallocate conf->disks to be suitable bigger. If this fails,
2112 * we simple return a failre status - no need to clean anything up.
2113 * 4/ allocate new pages for the new slots in the new stripe_heads.
2114 * If this fails, we don't bother trying the shrink the
2115 * stripe_heads down again, we just leave them as they are.
2116 * As each stripe_head is processed the new one is released into
2119 * Once step2 is started, we cannot afford to wait for a write,
2120 * so we use GFP_NOIO allocations.
2122 struct stripe_head
*osh
, *nsh
;
2123 LIST_HEAD(newstripes
);
2124 struct disk_info
*ndisks
;
2126 struct kmem_cache
*sc
;
2130 if (newsize
<= conf
->pool_size
)
2131 return 0; /* never bother to shrink */
2133 err
= md_allow_write(conf
->mddev
);
2138 sc
= kmem_cache_create(conf
->cache_name
[1-conf
->active_name
],
2139 sizeof(struct stripe_head
)+(newsize
-1)*sizeof(struct r5dev
),
2144 for (i
= conf
->max_nr_stripes
; i
; i
--) {
2145 nsh
= alloc_stripe(sc
, GFP_KERNEL
);
2149 nsh
->raid_conf
= conf
;
2150 list_add(&nsh
->lru
, &newstripes
);
2153 /* didn't get enough, give up */
2154 while (!list_empty(&newstripes
)) {
2155 nsh
= list_entry(newstripes
.next
, struct stripe_head
, lru
);
2156 list_del(&nsh
->lru
);
2157 kmem_cache_free(sc
, nsh
);
2159 kmem_cache_destroy(sc
);
2162 /* Step 2 - Must use GFP_NOIO now.
2163 * OK, we have enough stripes, start collecting inactive
2164 * stripes and copying them over
2168 list_for_each_entry(nsh
, &newstripes
, lru
) {
2169 lock_device_hash_lock(conf
, hash
);
2170 wait_event_cmd(conf
->wait_for_stripe
,
2171 !list_empty(conf
->inactive_list
+ hash
),
2172 unlock_device_hash_lock(conf
, hash
),
2173 lock_device_hash_lock(conf
, hash
));
2174 osh
= get_free_stripe(conf
, hash
);
2175 unlock_device_hash_lock(conf
, hash
);
2177 for(i
=0; i
<conf
->pool_size
; i
++) {
2178 nsh
->dev
[i
].page
= osh
->dev
[i
].page
;
2179 nsh
->dev
[i
].orig_page
= osh
->dev
[i
].page
;
2181 nsh
->hash_lock_index
= hash
;
2182 kmem_cache_free(conf
->slab_cache
, osh
);
2184 if (cnt
>= conf
->max_nr_stripes
/ NR_STRIPE_HASH_LOCKS
+
2185 !!((conf
->max_nr_stripes
% NR_STRIPE_HASH_LOCKS
) > hash
)) {
2190 kmem_cache_destroy(conf
->slab_cache
);
2193 * At this point, we are holding all the stripes so the array
2194 * is completely stalled, so now is a good time to resize
2195 * conf->disks and the scribble region
2197 ndisks
= kzalloc(newsize
* sizeof(struct disk_info
), GFP_NOIO
);
2199 for (i
=0; i
<conf
->raid_disks
; i
++)
2200 ndisks
[i
] = conf
->disks
[i
];
2202 conf
->disks
= ndisks
;
2206 /* Step 4, return new stripes to service */
2207 while(!list_empty(&newstripes
)) {
2208 nsh
= list_entry(newstripes
.next
, struct stripe_head
, lru
);
2209 list_del_init(&nsh
->lru
);
2211 for (i
=conf
->raid_disks
; i
< newsize
; i
++)
2212 if (nsh
->dev
[i
].page
== NULL
) {
2213 struct page
*p
= alloc_page(GFP_NOIO
);
2214 nsh
->dev
[i
].page
= p
;
2215 nsh
->dev
[i
].orig_page
= p
;
2219 release_stripe(nsh
);
2221 /* critical section pass, GFP_NOIO no longer needed */
2223 conf
->slab_cache
= sc
;
2224 conf
->active_name
= 1-conf
->active_name
;
2226 conf
->pool_size
= newsize
;
2230 static int drop_one_stripe(struct r5conf
*conf
)
2232 struct stripe_head
*sh
;
2233 int hash
= (conf
->max_nr_stripes
- 1) % NR_STRIPE_HASH_LOCKS
;
2235 spin_lock_irq(conf
->hash_locks
+ hash
);
2236 sh
= get_free_stripe(conf
, hash
);
2237 spin_unlock_irq(conf
->hash_locks
+ hash
);
2240 BUG_ON(atomic_read(&sh
->count
));
2242 kmem_cache_free(conf
->slab_cache
, sh
);
2243 atomic_dec(&conf
->active_stripes
);
2244 conf
->max_nr_stripes
--;
2248 static void shrink_stripes(struct r5conf
*conf
)
2250 while (conf
->max_nr_stripes
&&
2251 drop_one_stripe(conf
))
2254 if (conf
->slab_cache
)
2255 kmem_cache_destroy(conf
->slab_cache
);
2256 conf
->slab_cache
= NULL
;
2259 static void raid5_end_read_request(struct bio
* bi
, int error
)
2261 struct stripe_head
*sh
= bi
->bi_private
;
2262 struct r5conf
*conf
= sh
->raid_conf
;
2263 int disks
= sh
->disks
, i
;
2264 int uptodate
= test_bit(BIO_UPTODATE
, &bi
->bi_flags
);
2265 char b
[BDEVNAME_SIZE
];
2266 struct md_rdev
*rdev
= NULL
;
2269 for (i
=0 ; i
<disks
; i
++)
2270 if (bi
== &sh
->dev
[i
].req
)
2273 pr_debug("end_read_request %llu/%d, count: %d, uptodate %d.\n",
2274 (unsigned long long)sh
->sector
, i
, atomic_read(&sh
->count
),
2280 if (test_bit(R5_ReadRepl
, &sh
->dev
[i
].flags
))
2281 /* If replacement finished while this request was outstanding,
2282 * 'replacement' might be NULL already.
2283 * In that case it moved down to 'rdev'.
2284 * rdev is not removed until all requests are finished.
2286 rdev
= conf
->disks
[i
].replacement
;
2288 rdev
= conf
->disks
[i
].rdev
;
2290 if (use_new_offset(conf
, sh
))
2291 s
= sh
->sector
+ rdev
->new_data_offset
;
2293 s
= sh
->sector
+ rdev
->data_offset
;
2295 set_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
);
2296 if (test_bit(R5_ReadError
, &sh
->dev
[i
].flags
)) {
2297 /* Note that this cannot happen on a
2298 * replacement device. We just fail those on
2303 "md/raid:%s: read error corrected"
2304 " (%lu sectors at %llu on %s)\n",
2305 mdname(conf
->mddev
), STRIPE_SECTORS
,
2306 (unsigned long long)s
,
2307 bdevname(rdev
->bdev
, b
));
2308 atomic_add(STRIPE_SECTORS
, &rdev
->corrected_errors
);
2309 clear_bit(R5_ReadError
, &sh
->dev
[i
].flags
);
2310 clear_bit(R5_ReWrite
, &sh
->dev
[i
].flags
);
2311 } else if (test_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
))
2312 clear_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
);
2314 if (atomic_read(&rdev
->read_errors
))
2315 atomic_set(&rdev
->read_errors
, 0);
2317 const char *bdn
= bdevname(rdev
->bdev
, b
);
2321 clear_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
);
2322 atomic_inc(&rdev
->read_errors
);
2323 if (test_bit(R5_ReadRepl
, &sh
->dev
[i
].flags
))
2326 "md/raid:%s: read error on replacement device "
2327 "(sector %llu on %s).\n",
2328 mdname(conf
->mddev
),
2329 (unsigned long long)s
,
2331 else if (conf
->mddev
->degraded
>= conf
->max_degraded
) {
2335 "md/raid:%s: read error not correctable "
2336 "(sector %llu on %s).\n",
2337 mdname(conf
->mddev
),
2338 (unsigned long long)s
,
2340 } else if (test_bit(R5_ReWrite
, &sh
->dev
[i
].flags
)) {
2345 "md/raid:%s: read error NOT corrected!! "
2346 "(sector %llu on %s).\n",
2347 mdname(conf
->mddev
),
2348 (unsigned long long)s
,
2350 } else if (atomic_read(&rdev
->read_errors
)
2351 > conf
->max_nr_stripes
)
2353 "md/raid:%s: Too many read errors, failing device %s.\n",
2354 mdname(conf
->mddev
), bdn
);
2357 if (set_bad
&& test_bit(In_sync
, &rdev
->flags
)
2358 && !test_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
))
2361 if (test_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
)) {
2362 set_bit(R5_ReadError
, &sh
->dev
[i
].flags
);
2363 clear_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
);
2365 set_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
);
2367 clear_bit(R5_ReadError
, &sh
->dev
[i
].flags
);
2368 clear_bit(R5_ReWrite
, &sh
->dev
[i
].flags
);
2370 && test_bit(In_sync
, &rdev
->flags
)
2371 && rdev_set_badblocks(
2372 rdev
, sh
->sector
, STRIPE_SECTORS
, 0)))
2373 md_error(conf
->mddev
, rdev
);
2376 rdev_dec_pending(rdev
, conf
->mddev
);
2377 clear_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
2378 set_bit(STRIPE_HANDLE
, &sh
->state
);
2382 static void raid5_end_write_request(struct bio
*bi
, int error
)
2384 struct stripe_head
*sh
= bi
->bi_private
;
2385 struct r5conf
*conf
= sh
->raid_conf
;
2386 int disks
= sh
->disks
, i
;
2387 struct md_rdev
*uninitialized_var(rdev
);
2388 int uptodate
= test_bit(BIO_UPTODATE
, &bi
->bi_flags
);
2391 int replacement
= 0;
2393 for (i
= 0 ; i
< disks
; i
++) {
2394 if (bi
== &sh
->dev
[i
].req
) {
2395 rdev
= conf
->disks
[i
].rdev
;
2398 if (bi
== &sh
->dev
[i
].rreq
) {
2399 rdev
= conf
->disks
[i
].replacement
;
2403 /* rdev was removed and 'replacement'
2404 * replaced it. rdev is not removed
2405 * until all requests are finished.
2407 rdev
= conf
->disks
[i
].rdev
;
2411 pr_debug("end_write_request %llu/%d, count %d, uptodate: %d.\n",
2412 (unsigned long long)sh
->sector
, i
, atomic_read(&sh
->count
),
2421 md_error(conf
->mddev
, rdev
);
2422 else if (is_badblock(rdev
, sh
->sector
,
2424 &first_bad
, &bad_sectors
))
2425 set_bit(R5_MadeGoodRepl
, &sh
->dev
[i
].flags
);
2428 set_bit(STRIPE_DEGRADED
, &sh
->state
);
2429 set_bit(WriteErrorSeen
, &rdev
->flags
);
2430 set_bit(R5_WriteError
, &sh
->dev
[i
].flags
);
2431 if (!test_and_set_bit(WantReplacement
, &rdev
->flags
))
2432 set_bit(MD_RECOVERY_NEEDED
,
2433 &rdev
->mddev
->recovery
);
2434 } else if (is_badblock(rdev
, sh
->sector
,
2436 &first_bad
, &bad_sectors
)) {
2437 set_bit(R5_MadeGood
, &sh
->dev
[i
].flags
);
2438 if (test_bit(R5_ReadError
, &sh
->dev
[i
].flags
))
2439 /* That was a successful write so make
2440 * sure it looks like we already did
2443 set_bit(R5_ReWrite
, &sh
->dev
[i
].flags
);
2446 rdev_dec_pending(rdev
, conf
->mddev
);
2448 if (sh
->batch_head
&& !uptodate
&& !replacement
)
2449 set_bit(STRIPE_BATCH_ERR
, &sh
->batch_head
->state
);
2451 if (!test_and_clear_bit(R5_DOUBLE_LOCKED
, &sh
->dev
[i
].flags
))
2452 clear_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
2453 set_bit(STRIPE_HANDLE
, &sh
->state
);
2456 if (sh
->batch_head
&& sh
!= sh
->batch_head
)
2457 release_stripe(sh
->batch_head
);
2460 static sector_t
compute_blocknr(struct stripe_head
*sh
, int i
, int previous
);
2462 static void raid5_build_block(struct stripe_head
*sh
, int i
, int previous
)
2464 struct r5dev
*dev
= &sh
->dev
[i
];
2466 bio_init(&dev
->req
);
2467 dev
->req
.bi_io_vec
= &dev
->vec
;
2468 dev
->req
.bi_max_vecs
= 1;
2469 dev
->req
.bi_private
= sh
;
2471 bio_init(&dev
->rreq
);
2472 dev
->rreq
.bi_io_vec
= &dev
->rvec
;
2473 dev
->rreq
.bi_max_vecs
= 1;
2474 dev
->rreq
.bi_private
= sh
;
2477 dev
->sector
= compute_blocknr(sh
, i
, previous
);
2480 static void error(struct mddev
*mddev
, struct md_rdev
*rdev
)
2482 char b
[BDEVNAME_SIZE
];
2483 struct r5conf
*conf
= mddev
->private;
2484 unsigned long flags
;
2485 pr_debug("raid456: error called\n");
2487 spin_lock_irqsave(&conf
->device_lock
, flags
);
2488 clear_bit(In_sync
, &rdev
->flags
);
2489 mddev
->degraded
= calc_degraded(conf
);
2490 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
2491 set_bit(MD_RECOVERY_INTR
, &mddev
->recovery
);
2493 set_bit(Blocked
, &rdev
->flags
);
2494 set_bit(Faulty
, &rdev
->flags
);
2495 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
2497 "md/raid:%s: Disk failure on %s, disabling device.\n"
2498 "md/raid:%s: Operation continuing on %d devices.\n",
2500 bdevname(rdev
->bdev
, b
),
2502 conf
->raid_disks
- mddev
->degraded
);
2506 * Input: a 'big' sector number,
2507 * Output: index of the data and parity disk, and the sector # in them.
2509 static sector_t
raid5_compute_sector(struct r5conf
*conf
, sector_t r_sector
,
2510 int previous
, int *dd_idx
,
2511 struct stripe_head
*sh
)
2513 sector_t stripe
, stripe2
;
2514 sector_t chunk_number
;
2515 unsigned int chunk_offset
;
2518 sector_t new_sector
;
2519 int algorithm
= previous
? conf
->prev_algo
2521 int sectors_per_chunk
= previous
? conf
->prev_chunk_sectors
2522 : conf
->chunk_sectors
;
2523 int raid_disks
= previous
? conf
->previous_raid_disks
2525 int data_disks
= raid_disks
- conf
->max_degraded
;
2527 /* First compute the information on this sector */
2530 * Compute the chunk number and the sector offset inside the chunk
2532 chunk_offset
= sector_div(r_sector
, sectors_per_chunk
);
2533 chunk_number
= r_sector
;
2536 * Compute the stripe number
2538 stripe
= chunk_number
;
2539 *dd_idx
= sector_div(stripe
, data_disks
);
2542 * Select the parity disk based on the user selected algorithm.
2544 pd_idx
= qd_idx
= -1;
2545 switch(conf
->level
) {
2547 pd_idx
= data_disks
;
2550 switch (algorithm
) {
2551 case ALGORITHM_LEFT_ASYMMETRIC
:
2552 pd_idx
= data_disks
- sector_div(stripe2
, raid_disks
);
2553 if (*dd_idx
>= pd_idx
)
2556 case ALGORITHM_RIGHT_ASYMMETRIC
:
2557 pd_idx
= sector_div(stripe2
, raid_disks
);
2558 if (*dd_idx
>= pd_idx
)
2561 case ALGORITHM_LEFT_SYMMETRIC
:
2562 pd_idx
= data_disks
- sector_div(stripe2
, raid_disks
);
2563 *dd_idx
= (pd_idx
+ 1 + *dd_idx
) % raid_disks
;
2565 case ALGORITHM_RIGHT_SYMMETRIC
:
2566 pd_idx
= sector_div(stripe2
, raid_disks
);
2567 *dd_idx
= (pd_idx
+ 1 + *dd_idx
) % raid_disks
;
2569 case ALGORITHM_PARITY_0
:
2573 case ALGORITHM_PARITY_N
:
2574 pd_idx
= data_disks
;
2582 switch (algorithm
) {
2583 case ALGORITHM_LEFT_ASYMMETRIC
:
2584 pd_idx
= raid_disks
- 1 - sector_div(stripe2
, raid_disks
);
2585 qd_idx
= pd_idx
+ 1;
2586 if (pd_idx
== raid_disks
-1) {
2587 (*dd_idx
)++; /* Q D D D P */
2589 } else if (*dd_idx
>= pd_idx
)
2590 (*dd_idx
) += 2; /* D D P Q D */
2592 case ALGORITHM_RIGHT_ASYMMETRIC
:
2593 pd_idx
= sector_div(stripe2
, raid_disks
);
2594 qd_idx
= pd_idx
+ 1;
2595 if (pd_idx
== raid_disks
-1) {
2596 (*dd_idx
)++; /* Q D D D P */
2598 } else if (*dd_idx
>= pd_idx
)
2599 (*dd_idx
) += 2; /* D D P Q D */
2601 case ALGORITHM_LEFT_SYMMETRIC
:
2602 pd_idx
= raid_disks
- 1 - sector_div(stripe2
, raid_disks
);
2603 qd_idx
= (pd_idx
+ 1) % raid_disks
;
2604 *dd_idx
= (pd_idx
+ 2 + *dd_idx
) % raid_disks
;
2606 case ALGORITHM_RIGHT_SYMMETRIC
:
2607 pd_idx
= sector_div(stripe2
, raid_disks
);
2608 qd_idx
= (pd_idx
+ 1) % raid_disks
;
2609 *dd_idx
= (pd_idx
+ 2 + *dd_idx
) % raid_disks
;
2612 case ALGORITHM_PARITY_0
:
2617 case ALGORITHM_PARITY_N
:
2618 pd_idx
= data_disks
;
2619 qd_idx
= data_disks
+ 1;
2622 case ALGORITHM_ROTATING_ZERO_RESTART
:
2623 /* Exactly the same as RIGHT_ASYMMETRIC, but or
2624 * of blocks for computing Q is different.
2626 pd_idx
= sector_div(stripe2
, raid_disks
);
2627 qd_idx
= pd_idx
+ 1;
2628 if (pd_idx
== raid_disks
-1) {
2629 (*dd_idx
)++; /* Q D D D P */
2631 } else if (*dd_idx
>= pd_idx
)
2632 (*dd_idx
) += 2; /* D D P Q D */
2636 case ALGORITHM_ROTATING_N_RESTART
:
2637 /* Same a left_asymmetric, by first stripe is
2638 * D D D P Q rather than
2642 pd_idx
= raid_disks
- 1 - sector_div(stripe2
, raid_disks
);
2643 qd_idx
= pd_idx
+ 1;
2644 if (pd_idx
== raid_disks
-1) {
2645 (*dd_idx
)++; /* Q D D D P */
2647 } else if (*dd_idx
>= pd_idx
)
2648 (*dd_idx
) += 2; /* D D P Q D */
2652 case ALGORITHM_ROTATING_N_CONTINUE
:
2653 /* Same as left_symmetric but Q is before P */
2654 pd_idx
= raid_disks
- 1 - sector_div(stripe2
, raid_disks
);
2655 qd_idx
= (pd_idx
+ raid_disks
- 1) % raid_disks
;
2656 *dd_idx
= (pd_idx
+ 1 + *dd_idx
) % raid_disks
;
2660 case ALGORITHM_LEFT_ASYMMETRIC_6
:
2661 /* RAID5 left_asymmetric, with Q on last device */
2662 pd_idx
= data_disks
- sector_div(stripe2
, raid_disks
-1);
2663 if (*dd_idx
>= pd_idx
)
2665 qd_idx
= raid_disks
- 1;
2668 case ALGORITHM_RIGHT_ASYMMETRIC_6
:
2669 pd_idx
= sector_div(stripe2
, raid_disks
-1);
2670 if (*dd_idx
>= pd_idx
)
2672 qd_idx
= raid_disks
- 1;
2675 case ALGORITHM_LEFT_SYMMETRIC_6
:
2676 pd_idx
= data_disks
- sector_div(stripe2
, raid_disks
-1);
2677 *dd_idx
= (pd_idx
+ 1 + *dd_idx
) % (raid_disks
-1);
2678 qd_idx
= raid_disks
- 1;
2681 case ALGORITHM_RIGHT_SYMMETRIC_6
:
2682 pd_idx
= sector_div(stripe2
, raid_disks
-1);
2683 *dd_idx
= (pd_idx
+ 1 + *dd_idx
) % (raid_disks
-1);
2684 qd_idx
= raid_disks
- 1;
2687 case ALGORITHM_PARITY_0_6
:
2690 qd_idx
= raid_disks
- 1;
2700 sh
->pd_idx
= pd_idx
;
2701 sh
->qd_idx
= qd_idx
;
2702 sh
->ddf_layout
= ddf_layout
;
2705 * Finally, compute the new sector number
2707 new_sector
= (sector_t
)stripe
* sectors_per_chunk
+ chunk_offset
;
2711 static sector_t
compute_blocknr(struct stripe_head
*sh
, int i
, int previous
)
2713 struct r5conf
*conf
= sh
->raid_conf
;
2714 int raid_disks
= sh
->disks
;
2715 int data_disks
= raid_disks
- conf
->max_degraded
;
2716 sector_t new_sector
= sh
->sector
, check
;
2717 int sectors_per_chunk
= previous
? conf
->prev_chunk_sectors
2718 : conf
->chunk_sectors
;
2719 int algorithm
= previous
? conf
->prev_algo
2723 sector_t chunk_number
;
2724 int dummy1
, dd_idx
= i
;
2726 struct stripe_head sh2
;
2728 chunk_offset
= sector_div(new_sector
, sectors_per_chunk
);
2729 stripe
= new_sector
;
2731 if (i
== sh
->pd_idx
)
2733 switch(conf
->level
) {
2736 switch (algorithm
) {
2737 case ALGORITHM_LEFT_ASYMMETRIC
:
2738 case ALGORITHM_RIGHT_ASYMMETRIC
:
2742 case ALGORITHM_LEFT_SYMMETRIC
:
2743 case ALGORITHM_RIGHT_SYMMETRIC
:
2746 i
-= (sh
->pd_idx
+ 1);
2748 case ALGORITHM_PARITY_0
:
2751 case ALGORITHM_PARITY_N
:
2758 if (i
== sh
->qd_idx
)
2759 return 0; /* It is the Q disk */
2760 switch (algorithm
) {
2761 case ALGORITHM_LEFT_ASYMMETRIC
:
2762 case ALGORITHM_RIGHT_ASYMMETRIC
:
2763 case ALGORITHM_ROTATING_ZERO_RESTART
:
2764 case ALGORITHM_ROTATING_N_RESTART
:
2765 if (sh
->pd_idx
== raid_disks
-1)
2766 i
--; /* Q D D D P */
2767 else if (i
> sh
->pd_idx
)
2768 i
-= 2; /* D D P Q D */
2770 case ALGORITHM_LEFT_SYMMETRIC
:
2771 case ALGORITHM_RIGHT_SYMMETRIC
:
2772 if (sh
->pd_idx
== raid_disks
-1)
2773 i
--; /* Q D D D P */
2778 i
-= (sh
->pd_idx
+ 2);
2781 case ALGORITHM_PARITY_0
:
2784 case ALGORITHM_PARITY_N
:
2786 case ALGORITHM_ROTATING_N_CONTINUE
:
2787 /* Like left_symmetric, but P is before Q */
2788 if (sh
->pd_idx
== 0)
2789 i
--; /* P D D D Q */
2794 i
-= (sh
->pd_idx
+ 1);
2797 case ALGORITHM_LEFT_ASYMMETRIC_6
:
2798 case ALGORITHM_RIGHT_ASYMMETRIC_6
:
2802 case ALGORITHM_LEFT_SYMMETRIC_6
:
2803 case ALGORITHM_RIGHT_SYMMETRIC_6
:
2805 i
+= data_disks
+ 1;
2806 i
-= (sh
->pd_idx
+ 1);
2808 case ALGORITHM_PARITY_0_6
:
2817 chunk_number
= stripe
* data_disks
+ i
;
2818 r_sector
= chunk_number
* sectors_per_chunk
+ chunk_offset
;
2820 check
= raid5_compute_sector(conf
, r_sector
,
2821 previous
, &dummy1
, &sh2
);
2822 if (check
!= sh
->sector
|| dummy1
!= dd_idx
|| sh2
.pd_idx
!= sh
->pd_idx
2823 || sh2
.qd_idx
!= sh
->qd_idx
) {
2824 printk(KERN_ERR
"md/raid:%s: compute_blocknr: map not correct\n",
2825 mdname(conf
->mddev
));
2832 schedule_reconstruction(struct stripe_head
*sh
, struct stripe_head_state
*s
,
2833 int rcw
, int expand
)
2835 int i
, pd_idx
= sh
->pd_idx
, qd_idx
= sh
->qd_idx
, disks
= sh
->disks
;
2836 struct r5conf
*conf
= sh
->raid_conf
;
2837 int level
= conf
->level
;
2841 for (i
= disks
; i
--; ) {
2842 struct r5dev
*dev
= &sh
->dev
[i
];
2845 set_bit(R5_LOCKED
, &dev
->flags
);
2846 set_bit(R5_Wantdrain
, &dev
->flags
);
2848 clear_bit(R5_UPTODATE
, &dev
->flags
);
2852 /* if we are not expanding this is a proper write request, and
2853 * there will be bios with new data to be drained into the
2858 /* False alarm, nothing to do */
2860 sh
->reconstruct_state
= reconstruct_state_drain_run
;
2861 set_bit(STRIPE_OP_BIODRAIN
, &s
->ops_request
);
2863 sh
->reconstruct_state
= reconstruct_state_run
;
2865 set_bit(STRIPE_OP_RECONSTRUCT
, &s
->ops_request
);
2867 if (s
->locked
+ conf
->max_degraded
== disks
)
2868 if (!test_and_set_bit(STRIPE_FULL_WRITE
, &sh
->state
))
2869 atomic_inc(&conf
->pending_full_writes
);
2871 BUG_ON(!(test_bit(R5_UPTODATE
, &sh
->dev
[pd_idx
].flags
) ||
2872 test_bit(R5_Wantcompute
, &sh
->dev
[pd_idx
].flags
)));
2873 BUG_ON(level
== 6 &&
2874 (!(test_bit(R5_UPTODATE
, &sh
->dev
[qd_idx
].flags
) ||
2875 test_bit(R5_Wantcompute
, &sh
->dev
[qd_idx
].flags
))));
2877 for (i
= disks
; i
--; ) {
2878 struct r5dev
*dev
= &sh
->dev
[i
];
2879 if (i
== pd_idx
|| i
== qd_idx
)
2883 (test_bit(R5_UPTODATE
, &dev
->flags
) ||
2884 test_bit(R5_Wantcompute
, &dev
->flags
))) {
2885 set_bit(R5_Wantdrain
, &dev
->flags
);
2886 set_bit(R5_LOCKED
, &dev
->flags
);
2887 clear_bit(R5_UPTODATE
, &dev
->flags
);
2892 /* False alarm - nothing to do */
2894 sh
->reconstruct_state
= reconstruct_state_prexor_drain_run
;
2895 set_bit(STRIPE_OP_PREXOR
, &s
->ops_request
);
2896 set_bit(STRIPE_OP_BIODRAIN
, &s
->ops_request
);
2897 set_bit(STRIPE_OP_RECONSTRUCT
, &s
->ops_request
);
2900 /* keep the parity disk(s) locked while asynchronous operations
2903 set_bit(R5_LOCKED
, &sh
->dev
[pd_idx
].flags
);
2904 clear_bit(R5_UPTODATE
, &sh
->dev
[pd_idx
].flags
);
2908 int qd_idx
= sh
->qd_idx
;
2909 struct r5dev
*dev
= &sh
->dev
[qd_idx
];
2911 set_bit(R5_LOCKED
, &dev
->flags
);
2912 clear_bit(R5_UPTODATE
, &dev
->flags
);
2916 pr_debug("%s: stripe %llu locked: %d ops_request: %lx\n",
2917 __func__
, (unsigned long long)sh
->sector
,
2918 s
->locked
, s
->ops_request
);
2922 * Each stripe/dev can have one or more bion attached.
2923 * toread/towrite point to the first in a chain.
2924 * The bi_next chain must be in order.
2926 static int add_stripe_bio(struct stripe_head
*sh
, struct bio
*bi
, int dd_idx
,
2927 int forwrite
, int previous
)
2930 struct r5conf
*conf
= sh
->raid_conf
;
2933 pr_debug("adding bi b#%llu to stripe s#%llu\n",
2934 (unsigned long long)bi
->bi_iter
.bi_sector
,
2935 (unsigned long long)sh
->sector
);
2938 * If several bio share a stripe. The bio bi_phys_segments acts as a
2939 * reference count to avoid race. The reference count should already be
2940 * increased before this function is called (for example, in
2941 * make_request()), so other bio sharing this stripe will not free the
2942 * stripe. If a stripe is owned by one stripe, the stripe lock will
2945 spin_lock_irq(&sh
->stripe_lock
);
2946 /* Don't allow new IO added to stripes in batch list */
2950 bip
= &sh
->dev
[dd_idx
].towrite
;
2954 bip
= &sh
->dev
[dd_idx
].toread
;
2955 while (*bip
&& (*bip
)->bi_iter
.bi_sector
< bi
->bi_iter
.bi_sector
) {
2956 if (bio_end_sector(*bip
) > bi
->bi_iter
.bi_sector
)
2958 bip
= & (*bip
)->bi_next
;
2960 if (*bip
&& (*bip
)->bi_iter
.bi_sector
< bio_end_sector(bi
))
2963 if (!forwrite
|| previous
)
2964 clear_bit(STRIPE_BATCH_READY
, &sh
->state
);
2966 BUG_ON(*bip
&& bi
->bi_next
&& (*bip
) != bi
->bi_next
);
2970 raid5_inc_bi_active_stripes(bi
);
2973 /* check if page is covered */
2974 sector_t sector
= sh
->dev
[dd_idx
].sector
;
2975 for (bi
=sh
->dev
[dd_idx
].towrite
;
2976 sector
< sh
->dev
[dd_idx
].sector
+ STRIPE_SECTORS
&&
2977 bi
&& bi
->bi_iter
.bi_sector
<= sector
;
2978 bi
= r5_next_bio(bi
, sh
->dev
[dd_idx
].sector
)) {
2979 if (bio_end_sector(bi
) >= sector
)
2980 sector
= bio_end_sector(bi
);
2982 if (sector
>= sh
->dev
[dd_idx
].sector
+ STRIPE_SECTORS
)
2983 if (!test_and_set_bit(R5_OVERWRITE
, &sh
->dev
[dd_idx
].flags
))
2984 sh
->overwrite_disks
++;
2987 pr_debug("added bi b#%llu to stripe s#%llu, disk %d.\n",
2988 (unsigned long long)(*bip
)->bi_iter
.bi_sector
,
2989 (unsigned long long)sh
->sector
, dd_idx
);
2990 spin_unlock_irq(&sh
->stripe_lock
);
2992 if (conf
->mddev
->bitmap
&& firstwrite
) {
2993 bitmap_startwrite(conf
->mddev
->bitmap
, sh
->sector
,
2995 sh
->bm_seq
= conf
->seq_flush
+1;
2996 set_bit(STRIPE_BIT_DELAY
, &sh
->state
);
2999 if (stripe_can_batch(sh
))
3000 stripe_add_to_batch_list(conf
, sh
);
3004 set_bit(R5_Overlap
, &sh
->dev
[dd_idx
].flags
);
3005 spin_unlock_irq(&sh
->stripe_lock
);
3009 static void end_reshape(struct r5conf
*conf
);
3011 static void stripe_set_idx(sector_t stripe
, struct r5conf
*conf
, int previous
,
3012 struct stripe_head
*sh
)
3014 int sectors_per_chunk
=
3015 previous
? conf
->prev_chunk_sectors
: conf
->chunk_sectors
;
3017 int chunk_offset
= sector_div(stripe
, sectors_per_chunk
);
3018 int disks
= previous
? conf
->previous_raid_disks
: conf
->raid_disks
;
3020 raid5_compute_sector(conf
,
3021 stripe
* (disks
- conf
->max_degraded
)
3022 *sectors_per_chunk
+ chunk_offset
,
3028 handle_failed_stripe(struct r5conf
*conf
, struct stripe_head
*sh
,
3029 struct stripe_head_state
*s
, int disks
,
3030 struct bio
**return_bi
)
3033 BUG_ON(sh
->batch_head
);
3034 for (i
= disks
; i
--; ) {
3038 if (test_bit(R5_ReadError
, &sh
->dev
[i
].flags
)) {
3039 struct md_rdev
*rdev
;
3041 rdev
= rcu_dereference(conf
->disks
[i
].rdev
);
3042 if (rdev
&& test_bit(In_sync
, &rdev
->flags
))
3043 atomic_inc(&rdev
->nr_pending
);
3048 if (!rdev_set_badblocks(
3052 md_error(conf
->mddev
, rdev
);
3053 rdev_dec_pending(rdev
, conf
->mddev
);
3056 spin_lock_irq(&sh
->stripe_lock
);
3057 /* fail all writes first */
3058 bi
= sh
->dev
[i
].towrite
;
3059 sh
->dev
[i
].towrite
= NULL
;
3060 sh
->overwrite_disks
= 0;
3061 spin_unlock_irq(&sh
->stripe_lock
);
3065 if (test_and_clear_bit(R5_Overlap
, &sh
->dev
[i
].flags
))
3066 wake_up(&conf
->wait_for_overlap
);
3068 while (bi
&& bi
->bi_iter
.bi_sector
<
3069 sh
->dev
[i
].sector
+ STRIPE_SECTORS
) {
3070 struct bio
*nextbi
= r5_next_bio(bi
, sh
->dev
[i
].sector
);
3071 clear_bit(BIO_UPTODATE
, &bi
->bi_flags
);
3072 if (!raid5_dec_bi_active_stripes(bi
)) {
3073 md_write_end(conf
->mddev
);
3074 bi
->bi_next
= *return_bi
;
3080 bitmap_endwrite(conf
->mddev
->bitmap
, sh
->sector
,
3081 STRIPE_SECTORS
, 0, 0);
3083 /* and fail all 'written' */
3084 bi
= sh
->dev
[i
].written
;
3085 sh
->dev
[i
].written
= NULL
;
3086 if (test_and_clear_bit(R5_SkipCopy
, &sh
->dev
[i
].flags
)) {
3087 WARN_ON(test_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
));
3088 sh
->dev
[i
].page
= sh
->dev
[i
].orig_page
;
3091 if (bi
) bitmap_end
= 1;
3092 while (bi
&& bi
->bi_iter
.bi_sector
<
3093 sh
->dev
[i
].sector
+ STRIPE_SECTORS
) {
3094 struct bio
*bi2
= r5_next_bio(bi
, sh
->dev
[i
].sector
);
3095 clear_bit(BIO_UPTODATE
, &bi
->bi_flags
);
3096 if (!raid5_dec_bi_active_stripes(bi
)) {
3097 md_write_end(conf
->mddev
);
3098 bi
->bi_next
= *return_bi
;
3104 /* fail any reads if this device is non-operational and
3105 * the data has not reached the cache yet.
3107 if (!test_bit(R5_Wantfill
, &sh
->dev
[i
].flags
) &&
3108 (!test_bit(R5_Insync
, &sh
->dev
[i
].flags
) ||
3109 test_bit(R5_ReadError
, &sh
->dev
[i
].flags
))) {
3110 spin_lock_irq(&sh
->stripe_lock
);
3111 bi
= sh
->dev
[i
].toread
;
3112 sh
->dev
[i
].toread
= NULL
;
3113 spin_unlock_irq(&sh
->stripe_lock
);
3114 if (test_and_clear_bit(R5_Overlap
, &sh
->dev
[i
].flags
))
3115 wake_up(&conf
->wait_for_overlap
);
3116 while (bi
&& bi
->bi_iter
.bi_sector
<
3117 sh
->dev
[i
].sector
+ STRIPE_SECTORS
) {
3118 struct bio
*nextbi
=
3119 r5_next_bio(bi
, sh
->dev
[i
].sector
);
3120 clear_bit(BIO_UPTODATE
, &bi
->bi_flags
);
3121 if (!raid5_dec_bi_active_stripes(bi
)) {
3122 bi
->bi_next
= *return_bi
;
3129 bitmap_endwrite(conf
->mddev
->bitmap
, sh
->sector
,
3130 STRIPE_SECTORS
, 0, 0);
3131 /* If we were in the middle of a write the parity block might
3132 * still be locked - so just clear all R5_LOCKED flags
3134 clear_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
3137 if (test_and_clear_bit(STRIPE_FULL_WRITE
, &sh
->state
))
3138 if (atomic_dec_and_test(&conf
->pending_full_writes
))
3139 md_wakeup_thread(conf
->mddev
->thread
);
3143 handle_failed_sync(struct r5conf
*conf
, struct stripe_head
*sh
,
3144 struct stripe_head_state
*s
)
3149 BUG_ON(sh
->batch_head
);
3150 clear_bit(STRIPE_SYNCING
, &sh
->state
);
3151 if (test_and_clear_bit(R5_Overlap
, &sh
->dev
[sh
->pd_idx
].flags
))
3152 wake_up(&conf
->wait_for_overlap
);
3155 /* There is nothing more to do for sync/check/repair.
3156 * Don't even need to abort as that is handled elsewhere
3157 * if needed, and not always wanted e.g. if there is a known
3159 * For recover/replace we need to record a bad block on all
3160 * non-sync devices, or abort the recovery
3162 if (test_bit(MD_RECOVERY_RECOVER
, &conf
->mddev
->recovery
)) {
3163 /* During recovery devices cannot be removed, so
3164 * locking and refcounting of rdevs is not needed
3166 for (i
= 0; i
< conf
->raid_disks
; i
++) {
3167 struct md_rdev
*rdev
= conf
->disks
[i
].rdev
;
3169 && !test_bit(Faulty
, &rdev
->flags
)
3170 && !test_bit(In_sync
, &rdev
->flags
)
3171 && !rdev_set_badblocks(rdev
, sh
->sector
,
3174 rdev
= conf
->disks
[i
].replacement
;
3176 && !test_bit(Faulty
, &rdev
->flags
)
3177 && !test_bit(In_sync
, &rdev
->flags
)
3178 && !rdev_set_badblocks(rdev
, sh
->sector
,
3183 conf
->recovery_disabled
=
3184 conf
->mddev
->recovery_disabled
;
3186 md_done_sync(conf
->mddev
, STRIPE_SECTORS
, !abort
);
3189 static int want_replace(struct stripe_head
*sh
, int disk_idx
)
3191 struct md_rdev
*rdev
;
3193 /* Doing recovery so rcu locking not required */
3194 rdev
= sh
->raid_conf
->disks
[disk_idx
].replacement
;
3196 && !test_bit(Faulty
, &rdev
->flags
)
3197 && !test_bit(In_sync
, &rdev
->flags
)
3198 && (rdev
->recovery_offset
<= sh
->sector
3199 || rdev
->mddev
->recovery_cp
<= sh
->sector
))
3205 /* fetch_block - checks the given member device to see if its data needs
3206 * to be read or computed to satisfy a request.
3208 * Returns 1 when no more member devices need to be checked, otherwise returns
3209 * 0 to tell the loop in handle_stripe_fill to continue
3212 static int need_this_block(struct stripe_head
*sh
, struct stripe_head_state
*s
,
3213 int disk_idx
, int disks
)
3215 struct r5dev
*dev
= &sh
->dev
[disk_idx
];
3216 struct r5dev
*fdev
[2] = { &sh
->dev
[s
->failed_num
[0]],
3217 &sh
->dev
[s
->failed_num
[1]] };
3221 if (test_bit(R5_LOCKED
, &dev
->flags
) ||
3222 test_bit(R5_UPTODATE
, &dev
->flags
))
3223 /* No point reading this as we already have it or have
3224 * decided to get it.
3229 (dev
->towrite
&& !test_bit(R5_OVERWRITE
, &dev
->flags
)))
3230 /* We need this block to directly satisfy a request */
3233 if (s
->syncing
|| s
->expanding
||
3234 (s
->replacing
&& want_replace(sh
, disk_idx
)))
3235 /* When syncing, or expanding we read everything.
3236 * When replacing, we need the replaced block.
3240 if ((s
->failed
>= 1 && fdev
[0]->toread
) ||
3241 (s
->failed
>= 2 && fdev
[1]->toread
))
3242 /* If we want to read from a failed device, then
3243 * we need to actually read every other device.
3247 /* Sometimes neither read-modify-write nor reconstruct-write
3248 * cycles can work. In those cases we read every block we
3249 * can. Then the parity-update is certain to have enough to
3251 * This can only be a problem when we need to write something,
3252 * and some device has failed. If either of those tests
3253 * fail we need look no further.
3255 if (!s
->failed
|| !s
->to_write
)
3258 if (test_bit(R5_Insync
, &dev
->flags
) &&
3259 !test_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
3260 /* Pre-reads at not permitted until after short delay
3261 * to gather multiple requests. However if this
3262 * device is no Insync, the block could only be be computed
3263 * and there is no need to delay that.
3267 for (i
= 0; i
< s
->failed
; i
++) {
3268 if (fdev
[i
]->towrite
&&
3269 !test_bit(R5_UPTODATE
, &fdev
[i
]->flags
) &&
3270 !test_bit(R5_OVERWRITE
, &fdev
[i
]->flags
))
3271 /* If we have a partial write to a failed
3272 * device, then we will need to reconstruct
3273 * the content of that device, so all other
3274 * devices must be read.
3279 /* If we are forced to do a reconstruct-write, either because
3280 * the current RAID6 implementation only supports that, or
3281 * or because parity cannot be trusted and we are currently
3282 * recovering it, there is extra need to be careful.
3283 * If one of the devices that we would need to read, because
3284 * it is not being overwritten (and maybe not written at all)
3285 * is missing/faulty, then we need to read everything we can.
3287 if (sh
->raid_conf
->level
!= 6 &&
3288 sh
->sector
< sh
->raid_conf
->mddev
->recovery_cp
)
3289 /* reconstruct-write isn't being forced */
3291 for (i
= 0; i
< s
->failed
; i
++) {
3292 if (s
->failed_num
[i
] != sh
->pd_idx
&&
3293 s
->failed_num
[i
] != sh
->qd_idx
&&
3294 !test_bit(R5_UPTODATE
, &fdev
[i
]->flags
) &&
3295 !test_bit(R5_OVERWRITE
, &fdev
[i
]->flags
))
3302 static int fetch_block(struct stripe_head
*sh
, struct stripe_head_state
*s
,
3303 int disk_idx
, int disks
)
3305 struct r5dev
*dev
= &sh
->dev
[disk_idx
];
3307 /* is the data in this block needed, and can we get it? */
3308 if (need_this_block(sh
, s
, disk_idx
, disks
)) {
3309 /* we would like to get this block, possibly by computing it,
3310 * otherwise read it if the backing disk is insync
3312 BUG_ON(test_bit(R5_Wantcompute
, &dev
->flags
));
3313 BUG_ON(test_bit(R5_Wantread
, &dev
->flags
));
3314 BUG_ON(sh
->batch_head
);
3315 if ((s
->uptodate
== disks
- 1) &&
3316 (s
->failed
&& (disk_idx
== s
->failed_num
[0] ||
3317 disk_idx
== s
->failed_num
[1]))) {
3318 /* have disk failed, and we're requested to fetch it;
3321 pr_debug("Computing stripe %llu block %d\n",
3322 (unsigned long long)sh
->sector
, disk_idx
);
3323 set_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
3324 set_bit(STRIPE_OP_COMPUTE_BLK
, &s
->ops_request
);
3325 set_bit(R5_Wantcompute
, &dev
->flags
);
3326 sh
->ops
.target
= disk_idx
;
3327 sh
->ops
.target2
= -1; /* no 2nd target */
3329 /* Careful: from this point on 'uptodate' is in the eye
3330 * of raid_run_ops which services 'compute' operations
3331 * before writes. R5_Wantcompute flags a block that will
3332 * be R5_UPTODATE by the time it is needed for a
3333 * subsequent operation.
3337 } else if (s
->uptodate
== disks
-2 && s
->failed
>= 2) {
3338 /* Computing 2-failure is *very* expensive; only
3339 * do it if failed >= 2
3342 for (other
= disks
; other
--; ) {
3343 if (other
== disk_idx
)
3345 if (!test_bit(R5_UPTODATE
,
3346 &sh
->dev
[other
].flags
))
3350 pr_debug("Computing stripe %llu blocks %d,%d\n",
3351 (unsigned long long)sh
->sector
,
3353 set_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
3354 set_bit(STRIPE_OP_COMPUTE_BLK
, &s
->ops_request
);
3355 set_bit(R5_Wantcompute
, &sh
->dev
[disk_idx
].flags
);
3356 set_bit(R5_Wantcompute
, &sh
->dev
[other
].flags
);
3357 sh
->ops
.target
= disk_idx
;
3358 sh
->ops
.target2
= other
;
3362 } else if (test_bit(R5_Insync
, &dev
->flags
)) {
3363 set_bit(R5_LOCKED
, &dev
->flags
);
3364 set_bit(R5_Wantread
, &dev
->flags
);
3366 pr_debug("Reading block %d (sync=%d)\n",
3367 disk_idx
, s
->syncing
);
3375 * handle_stripe_fill - read or compute data to satisfy pending requests.
3377 static void handle_stripe_fill(struct stripe_head
*sh
,
3378 struct stripe_head_state
*s
,
3383 /* look for blocks to read/compute, skip this if a compute
3384 * is already in flight, or if the stripe contents are in the
3385 * midst of changing due to a write
3387 if (!test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
) && !sh
->check_state
&&
3388 !sh
->reconstruct_state
)
3389 for (i
= disks
; i
--; )
3390 if (fetch_block(sh
, s
, i
, disks
))
3392 set_bit(STRIPE_HANDLE
, &sh
->state
);
3395 /* handle_stripe_clean_event
3396 * any written block on an uptodate or failed drive can be returned.
3397 * Note that if we 'wrote' to a failed drive, it will be UPTODATE, but
3398 * never LOCKED, so we don't need to test 'failed' directly.
3400 static void handle_stripe_clean_event(struct r5conf
*conf
,
3401 struct stripe_head
*sh
, int disks
, struct bio
**return_bi
)
3405 int discard_pending
= 0;
3406 struct stripe_head
*head_sh
= sh
;
3407 bool do_endio
= false;
3410 for (i
= disks
; i
--; )
3411 if (sh
->dev
[i
].written
) {
3413 if (!test_bit(R5_LOCKED
, &dev
->flags
) &&
3414 (test_bit(R5_UPTODATE
, &dev
->flags
) ||
3415 test_bit(R5_Discard
, &dev
->flags
) ||
3416 test_bit(R5_SkipCopy
, &dev
->flags
))) {
3417 /* We can return any write requests */
3418 struct bio
*wbi
, *wbi2
;
3419 pr_debug("Return write for disc %d\n", i
);
3420 if (test_and_clear_bit(R5_Discard
, &dev
->flags
))
3421 clear_bit(R5_UPTODATE
, &dev
->flags
);
3422 if (test_and_clear_bit(R5_SkipCopy
, &dev
->flags
)) {
3423 WARN_ON(test_bit(R5_UPTODATE
, &dev
->flags
));
3428 dev
->page
= dev
->orig_page
;
3430 dev
->written
= NULL
;
3431 while (wbi
&& wbi
->bi_iter
.bi_sector
<
3432 dev
->sector
+ STRIPE_SECTORS
) {
3433 wbi2
= r5_next_bio(wbi
, dev
->sector
);
3434 if (!raid5_dec_bi_active_stripes(wbi
)) {
3435 md_write_end(conf
->mddev
);
3436 wbi
->bi_next
= *return_bi
;
3441 bitmap_endwrite(conf
->mddev
->bitmap
, sh
->sector
,
3443 !test_bit(STRIPE_DEGRADED
, &sh
->state
),
3445 if (head_sh
->batch_head
) {
3446 sh
= list_first_entry(&sh
->batch_list
,
3449 if (sh
!= head_sh
) {
3456 } else if (test_bit(R5_Discard
, &dev
->flags
))
3457 discard_pending
= 1;
3458 WARN_ON(test_bit(R5_SkipCopy
, &dev
->flags
));
3459 WARN_ON(dev
->page
!= dev
->orig_page
);
3461 if (!discard_pending
&&
3462 test_bit(R5_Discard
, &sh
->dev
[sh
->pd_idx
].flags
)) {
3463 clear_bit(R5_Discard
, &sh
->dev
[sh
->pd_idx
].flags
);
3464 clear_bit(R5_UPTODATE
, &sh
->dev
[sh
->pd_idx
].flags
);
3465 if (sh
->qd_idx
>= 0) {
3466 clear_bit(R5_Discard
, &sh
->dev
[sh
->qd_idx
].flags
);
3467 clear_bit(R5_UPTODATE
, &sh
->dev
[sh
->qd_idx
].flags
);
3469 /* now that discard is done we can proceed with any sync */
3470 clear_bit(STRIPE_DISCARD
, &sh
->state
);
3472 * SCSI discard will change some bio fields and the stripe has
3473 * no updated data, so remove it from hash list and the stripe
3474 * will be reinitialized
3476 spin_lock_irq(&conf
->device_lock
);
3479 if (head_sh
->batch_head
) {
3480 sh
= list_first_entry(&sh
->batch_list
,
3481 struct stripe_head
, batch_list
);
3485 spin_unlock_irq(&conf
->device_lock
);
3488 if (test_bit(STRIPE_SYNC_REQUESTED
, &sh
->state
))
3489 set_bit(STRIPE_HANDLE
, &sh
->state
);
3493 if (test_and_clear_bit(STRIPE_FULL_WRITE
, &sh
->state
))
3494 if (atomic_dec_and_test(&conf
->pending_full_writes
))
3495 md_wakeup_thread(conf
->mddev
->thread
);
3497 if (!head_sh
->batch_head
|| !do_endio
)
3499 for (i
= 0; i
< head_sh
->disks
; i
++) {
3500 if (test_and_clear_bit(R5_Overlap
, &head_sh
->dev
[i
].flags
))
3503 while (!list_empty(&head_sh
->batch_list
)) {
3505 sh
= list_first_entry(&head_sh
->batch_list
,
3506 struct stripe_head
, batch_list
);
3507 list_del_init(&sh
->batch_list
);
3509 set_mask_bits(&sh
->state
, ~STRIPE_EXPAND_SYNC_FLAG
,
3510 head_sh
->state
& ~((1 << STRIPE_ACTIVE
) |
3511 (1 << STRIPE_PREREAD_ACTIVE
) |
3512 STRIPE_EXPAND_SYNC_FLAG
));
3513 sh
->check_state
= head_sh
->check_state
;
3514 sh
->reconstruct_state
= head_sh
->reconstruct_state
;
3515 for (i
= 0; i
< sh
->disks
; i
++) {
3516 if (test_and_clear_bit(R5_Overlap
, &sh
->dev
[i
].flags
))
3518 sh
->dev
[i
].flags
= head_sh
->dev
[i
].flags
;
3521 spin_lock_irq(&sh
->stripe_lock
);
3522 sh
->batch_head
= NULL
;
3523 spin_unlock_irq(&sh
->stripe_lock
);
3524 if (sh
->state
& STRIPE_EXPAND_SYNC_FLAG
)
3525 set_bit(STRIPE_HANDLE
, &sh
->state
);
3529 spin_lock_irq(&head_sh
->stripe_lock
);
3530 head_sh
->batch_head
= NULL
;
3531 spin_unlock_irq(&head_sh
->stripe_lock
);
3532 wake_up_nr(&conf
->wait_for_overlap
, wakeup_nr
);
3533 if (head_sh
->state
& STRIPE_EXPAND_SYNC_FLAG
)
3534 set_bit(STRIPE_HANDLE
, &head_sh
->state
);
3537 static void handle_stripe_dirtying(struct r5conf
*conf
,
3538 struct stripe_head
*sh
,
3539 struct stripe_head_state
*s
,
3542 int rmw
= 0, rcw
= 0, i
;
3543 sector_t recovery_cp
= conf
->mddev
->recovery_cp
;
3545 /* Check whether resync is now happening or should start.
3546 * If yes, then the array is dirty (after unclean shutdown or
3547 * initial creation), so parity in some stripes might be inconsistent.
3548 * In this case, we need to always do reconstruct-write, to ensure
3549 * that in case of drive failure or read-error correction, we
3550 * generate correct data from the parity.
3552 if (conf
->rmw_level
== PARITY_DISABLE_RMW
||
3553 (recovery_cp
< MaxSector
&& sh
->sector
>= recovery_cp
&&
3555 /* Calculate the real rcw later - for now make it
3556 * look like rcw is cheaper
3559 pr_debug("force RCW rmw_level=%u, recovery_cp=%llu sh->sector=%llu\n",
3560 conf
->rmw_level
, (unsigned long long)recovery_cp
,
3561 (unsigned long long)sh
->sector
);
3562 } else for (i
= disks
; i
--; ) {
3563 /* would I have to read this buffer for read_modify_write */
3564 struct r5dev
*dev
= &sh
->dev
[i
];
3565 if ((dev
->towrite
|| i
== sh
->pd_idx
|| i
== sh
->qd_idx
) &&
3566 !test_bit(R5_LOCKED
, &dev
->flags
) &&
3567 !(test_bit(R5_UPTODATE
, &dev
->flags
) ||
3568 test_bit(R5_Wantcompute
, &dev
->flags
))) {
3569 if (test_bit(R5_Insync
, &dev
->flags
))
3572 rmw
+= 2*disks
; /* cannot read it */
3574 /* Would I have to read this buffer for reconstruct_write */
3575 if (!test_bit(R5_OVERWRITE
, &dev
->flags
) &&
3576 i
!= sh
->pd_idx
&& i
!= sh
->qd_idx
&&
3577 !test_bit(R5_LOCKED
, &dev
->flags
) &&
3578 !(test_bit(R5_UPTODATE
, &dev
->flags
) ||
3579 test_bit(R5_Wantcompute
, &dev
->flags
))) {
3580 if (test_bit(R5_Insync
, &dev
->flags
))
3586 pr_debug("for sector %llu, rmw=%d rcw=%d\n",
3587 (unsigned long long)sh
->sector
, rmw
, rcw
);
3588 set_bit(STRIPE_HANDLE
, &sh
->state
);
3589 if ((rmw
< rcw
|| (rmw
== rcw
&& conf
->rmw_level
== PARITY_ENABLE_RMW
)) && rmw
> 0) {
3590 /* prefer read-modify-write, but need to get some data */
3591 if (conf
->mddev
->queue
)
3592 blk_add_trace_msg(conf
->mddev
->queue
,
3593 "raid5 rmw %llu %d",
3594 (unsigned long long)sh
->sector
, rmw
);
3595 for (i
= disks
; i
--; ) {
3596 struct r5dev
*dev
= &sh
->dev
[i
];
3597 if ((dev
->towrite
|| i
== sh
->pd_idx
|| i
== sh
->qd_idx
) &&
3598 !test_bit(R5_LOCKED
, &dev
->flags
) &&
3599 !(test_bit(R5_UPTODATE
, &dev
->flags
) ||
3600 test_bit(R5_Wantcompute
, &dev
->flags
)) &&
3601 test_bit(R5_Insync
, &dev
->flags
)) {
3602 if (test_bit(STRIPE_PREREAD_ACTIVE
,
3604 pr_debug("Read_old block %d for r-m-w\n",
3606 set_bit(R5_LOCKED
, &dev
->flags
);
3607 set_bit(R5_Wantread
, &dev
->flags
);
3610 set_bit(STRIPE_DELAYED
, &sh
->state
);
3611 set_bit(STRIPE_HANDLE
, &sh
->state
);
3616 if ((rcw
< rmw
|| (rcw
== rmw
&& conf
->rmw_level
!= PARITY_ENABLE_RMW
)) && rcw
> 0) {
3617 /* want reconstruct write, but need to get some data */
3620 for (i
= disks
; i
--; ) {
3621 struct r5dev
*dev
= &sh
->dev
[i
];
3622 if (!test_bit(R5_OVERWRITE
, &dev
->flags
) &&
3623 i
!= sh
->pd_idx
&& i
!= sh
->qd_idx
&&
3624 !test_bit(R5_LOCKED
, &dev
->flags
) &&
3625 !(test_bit(R5_UPTODATE
, &dev
->flags
) ||
3626 test_bit(R5_Wantcompute
, &dev
->flags
))) {
3628 if (test_bit(R5_Insync
, &dev
->flags
) &&
3629 test_bit(STRIPE_PREREAD_ACTIVE
,
3631 pr_debug("Read_old block "
3632 "%d for Reconstruct\n", i
);
3633 set_bit(R5_LOCKED
, &dev
->flags
);
3634 set_bit(R5_Wantread
, &dev
->flags
);
3638 set_bit(STRIPE_DELAYED
, &sh
->state
);
3639 set_bit(STRIPE_HANDLE
, &sh
->state
);
3643 if (rcw
&& conf
->mddev
->queue
)
3644 blk_add_trace_msg(conf
->mddev
->queue
, "raid5 rcw %llu %d %d %d",
3645 (unsigned long long)sh
->sector
,
3646 rcw
, qread
, test_bit(STRIPE_DELAYED
, &sh
->state
));
3649 if (rcw
> disks
&& rmw
> disks
&&
3650 !test_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
3651 set_bit(STRIPE_DELAYED
, &sh
->state
);
3653 /* now if nothing is locked, and if we have enough data,
3654 * we can start a write request
3656 /* since handle_stripe can be called at any time we need to handle the
3657 * case where a compute block operation has been submitted and then a
3658 * subsequent call wants to start a write request. raid_run_ops only
3659 * handles the case where compute block and reconstruct are requested
3660 * simultaneously. If this is not the case then new writes need to be
3661 * held off until the compute completes.
3663 if ((s
->req_compute
|| !test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
)) &&
3664 (s
->locked
== 0 && (rcw
== 0 || rmw
== 0) &&
3665 !test_bit(STRIPE_BIT_DELAY
, &sh
->state
)))
3666 schedule_reconstruction(sh
, s
, rcw
== 0, 0);
3669 static void handle_parity_checks5(struct r5conf
*conf
, struct stripe_head
*sh
,
3670 struct stripe_head_state
*s
, int disks
)
3672 struct r5dev
*dev
= NULL
;
3674 BUG_ON(sh
->batch_head
);
3675 set_bit(STRIPE_HANDLE
, &sh
->state
);
3677 switch (sh
->check_state
) {
3678 case check_state_idle
:
3679 /* start a new check operation if there are no failures */
3680 if (s
->failed
== 0) {
3681 BUG_ON(s
->uptodate
!= disks
);
3682 sh
->check_state
= check_state_run
;
3683 set_bit(STRIPE_OP_CHECK
, &s
->ops_request
);
3684 clear_bit(R5_UPTODATE
, &sh
->dev
[sh
->pd_idx
].flags
);
3688 dev
= &sh
->dev
[s
->failed_num
[0]];
3690 case check_state_compute_result
:
3691 sh
->check_state
= check_state_idle
;
3693 dev
= &sh
->dev
[sh
->pd_idx
];
3695 /* check that a write has not made the stripe insync */
3696 if (test_bit(STRIPE_INSYNC
, &sh
->state
))
3699 /* either failed parity check, or recovery is happening */
3700 BUG_ON(!test_bit(R5_UPTODATE
, &dev
->flags
));
3701 BUG_ON(s
->uptodate
!= disks
);
3703 set_bit(R5_LOCKED
, &dev
->flags
);
3705 set_bit(R5_Wantwrite
, &dev
->flags
);
3707 clear_bit(STRIPE_DEGRADED
, &sh
->state
);
3708 set_bit(STRIPE_INSYNC
, &sh
->state
);
3710 case check_state_run
:
3711 break; /* we will be called again upon completion */
3712 case check_state_check_result
:
3713 sh
->check_state
= check_state_idle
;
3715 /* if a failure occurred during the check operation, leave
3716 * STRIPE_INSYNC not set and let the stripe be handled again
3721 /* handle a successful check operation, if parity is correct
3722 * we are done. Otherwise update the mismatch count and repair
3723 * parity if !MD_RECOVERY_CHECK
3725 if ((sh
->ops
.zero_sum_result
& SUM_CHECK_P_RESULT
) == 0)
3726 /* parity is correct (on disc,
3727 * not in buffer any more)
3729 set_bit(STRIPE_INSYNC
, &sh
->state
);
3731 atomic64_add(STRIPE_SECTORS
, &conf
->mddev
->resync_mismatches
);
3732 if (test_bit(MD_RECOVERY_CHECK
, &conf
->mddev
->recovery
))
3733 /* don't try to repair!! */
3734 set_bit(STRIPE_INSYNC
, &sh
->state
);
3736 sh
->check_state
= check_state_compute_run
;
3737 set_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
3738 set_bit(STRIPE_OP_COMPUTE_BLK
, &s
->ops_request
);
3739 set_bit(R5_Wantcompute
,
3740 &sh
->dev
[sh
->pd_idx
].flags
);
3741 sh
->ops
.target
= sh
->pd_idx
;
3742 sh
->ops
.target2
= -1;
3747 case check_state_compute_run
:
3750 printk(KERN_ERR
"%s: unknown check_state: %d sector: %llu\n",
3751 __func__
, sh
->check_state
,
3752 (unsigned long long) sh
->sector
);
3757 static void handle_parity_checks6(struct r5conf
*conf
, struct stripe_head
*sh
,
3758 struct stripe_head_state
*s
,
3761 int pd_idx
= sh
->pd_idx
;
3762 int qd_idx
= sh
->qd_idx
;
3765 BUG_ON(sh
->batch_head
);
3766 set_bit(STRIPE_HANDLE
, &sh
->state
);
3768 BUG_ON(s
->failed
> 2);
3770 /* Want to check and possibly repair P and Q.
3771 * However there could be one 'failed' device, in which
3772 * case we can only check one of them, possibly using the
3773 * other to generate missing data
3776 switch (sh
->check_state
) {
3777 case check_state_idle
:
3778 /* start a new check operation if there are < 2 failures */
3779 if (s
->failed
== s
->q_failed
) {
3780 /* The only possible failed device holds Q, so it
3781 * makes sense to check P (If anything else were failed,
3782 * we would have used P to recreate it).
3784 sh
->check_state
= check_state_run
;
3786 if (!s
->q_failed
&& s
->failed
< 2) {
3787 /* Q is not failed, and we didn't use it to generate
3788 * anything, so it makes sense to check it
3790 if (sh
->check_state
== check_state_run
)
3791 sh
->check_state
= check_state_run_pq
;
3793 sh
->check_state
= check_state_run_q
;
3796 /* discard potentially stale zero_sum_result */
3797 sh
->ops
.zero_sum_result
= 0;
3799 if (sh
->check_state
== check_state_run
) {
3800 /* async_xor_zero_sum destroys the contents of P */
3801 clear_bit(R5_UPTODATE
, &sh
->dev
[pd_idx
].flags
);
3804 if (sh
->check_state
>= check_state_run
&&
3805 sh
->check_state
<= check_state_run_pq
) {
3806 /* async_syndrome_zero_sum preserves P and Q, so
3807 * no need to mark them !uptodate here
3809 set_bit(STRIPE_OP_CHECK
, &s
->ops_request
);
3813 /* we have 2-disk failure */
3814 BUG_ON(s
->failed
!= 2);
3816 case check_state_compute_result
:
3817 sh
->check_state
= check_state_idle
;
3819 /* check that a write has not made the stripe insync */
3820 if (test_bit(STRIPE_INSYNC
, &sh
->state
))
3823 /* now write out any block on a failed drive,
3824 * or P or Q if they were recomputed
3826 BUG_ON(s
->uptodate
< disks
- 1); /* We don't need Q to recover */
3827 if (s
->failed
== 2) {
3828 dev
= &sh
->dev
[s
->failed_num
[1]];
3830 set_bit(R5_LOCKED
, &dev
->flags
);
3831 set_bit(R5_Wantwrite
, &dev
->flags
);
3833 if (s
->failed
>= 1) {
3834 dev
= &sh
->dev
[s
->failed_num
[0]];
3836 set_bit(R5_LOCKED
, &dev
->flags
);
3837 set_bit(R5_Wantwrite
, &dev
->flags
);
3839 if (sh
->ops
.zero_sum_result
& SUM_CHECK_P_RESULT
) {
3840 dev
= &sh
->dev
[pd_idx
];
3842 set_bit(R5_LOCKED
, &dev
->flags
);
3843 set_bit(R5_Wantwrite
, &dev
->flags
);
3845 if (sh
->ops
.zero_sum_result
& SUM_CHECK_Q_RESULT
) {
3846 dev
= &sh
->dev
[qd_idx
];
3848 set_bit(R5_LOCKED
, &dev
->flags
);
3849 set_bit(R5_Wantwrite
, &dev
->flags
);
3851 clear_bit(STRIPE_DEGRADED
, &sh
->state
);
3853 set_bit(STRIPE_INSYNC
, &sh
->state
);
3855 case check_state_run
:
3856 case check_state_run_q
:
3857 case check_state_run_pq
:
3858 break; /* we will be called again upon completion */
3859 case check_state_check_result
:
3860 sh
->check_state
= check_state_idle
;
3862 /* handle a successful check operation, if parity is correct
3863 * we are done. Otherwise update the mismatch count and repair
3864 * parity if !MD_RECOVERY_CHECK
3866 if (sh
->ops
.zero_sum_result
== 0) {
3867 /* both parities are correct */
3869 set_bit(STRIPE_INSYNC
, &sh
->state
);
3871 /* in contrast to the raid5 case we can validate
3872 * parity, but still have a failure to write
3875 sh
->check_state
= check_state_compute_result
;
3876 /* Returning at this point means that we may go
3877 * off and bring p and/or q uptodate again so
3878 * we make sure to check zero_sum_result again
3879 * to verify if p or q need writeback
3883 atomic64_add(STRIPE_SECTORS
, &conf
->mddev
->resync_mismatches
);
3884 if (test_bit(MD_RECOVERY_CHECK
, &conf
->mddev
->recovery
))
3885 /* don't try to repair!! */
3886 set_bit(STRIPE_INSYNC
, &sh
->state
);
3888 int *target
= &sh
->ops
.target
;
3890 sh
->ops
.target
= -1;
3891 sh
->ops
.target2
= -1;
3892 sh
->check_state
= check_state_compute_run
;
3893 set_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
3894 set_bit(STRIPE_OP_COMPUTE_BLK
, &s
->ops_request
);
3895 if (sh
->ops
.zero_sum_result
& SUM_CHECK_P_RESULT
) {
3896 set_bit(R5_Wantcompute
,
3897 &sh
->dev
[pd_idx
].flags
);
3899 target
= &sh
->ops
.target2
;
3902 if (sh
->ops
.zero_sum_result
& SUM_CHECK_Q_RESULT
) {
3903 set_bit(R5_Wantcompute
,
3904 &sh
->dev
[qd_idx
].flags
);
3911 case check_state_compute_run
:
3914 printk(KERN_ERR
"%s: unknown check_state: %d sector: %llu\n",
3915 __func__
, sh
->check_state
,
3916 (unsigned long long) sh
->sector
);
3921 static void handle_stripe_expansion(struct r5conf
*conf
, struct stripe_head
*sh
)
3925 /* We have read all the blocks in this stripe and now we need to
3926 * copy some of them into a target stripe for expand.
3928 struct dma_async_tx_descriptor
*tx
= NULL
;
3929 BUG_ON(sh
->batch_head
);
3930 clear_bit(STRIPE_EXPAND_SOURCE
, &sh
->state
);
3931 for (i
= 0; i
< sh
->disks
; i
++)
3932 if (i
!= sh
->pd_idx
&& i
!= sh
->qd_idx
) {
3934 struct stripe_head
*sh2
;
3935 struct async_submit_ctl submit
;
3937 sector_t bn
= compute_blocknr(sh
, i
, 1);
3938 sector_t s
= raid5_compute_sector(conf
, bn
, 0,
3940 sh2
= get_active_stripe(conf
, s
, 0, 1, 1);
3942 /* so far only the early blocks of this stripe
3943 * have been requested. When later blocks
3944 * get requested, we will try again
3947 if (!test_bit(STRIPE_EXPANDING
, &sh2
->state
) ||
3948 test_bit(R5_Expanded
, &sh2
->dev
[dd_idx
].flags
)) {
3949 /* must have already done this block */
3950 release_stripe(sh2
);
3954 /* place all the copies on one channel */
3955 init_async_submit(&submit
, 0, tx
, NULL
, NULL
, NULL
);
3956 tx
= async_memcpy(sh2
->dev
[dd_idx
].page
,
3957 sh
->dev
[i
].page
, 0, 0, STRIPE_SIZE
,
3960 set_bit(R5_Expanded
, &sh2
->dev
[dd_idx
].flags
);
3961 set_bit(R5_UPTODATE
, &sh2
->dev
[dd_idx
].flags
);
3962 for (j
= 0; j
< conf
->raid_disks
; j
++)
3963 if (j
!= sh2
->pd_idx
&&
3965 !test_bit(R5_Expanded
, &sh2
->dev
[j
].flags
))
3967 if (j
== conf
->raid_disks
) {
3968 set_bit(STRIPE_EXPAND_READY
, &sh2
->state
);
3969 set_bit(STRIPE_HANDLE
, &sh2
->state
);
3971 release_stripe(sh2
);
3974 /* done submitting copies, wait for them to complete */
3975 async_tx_quiesce(&tx
);
3979 * handle_stripe - do things to a stripe.
3981 * We lock the stripe by setting STRIPE_ACTIVE and then examine the
3982 * state of various bits to see what needs to be done.
3984 * return some read requests which now have data
3985 * return some write requests which are safely on storage
3986 * schedule a read on some buffers
3987 * schedule a write of some buffers
3988 * return confirmation of parity correctness
3992 static void analyse_stripe(struct stripe_head
*sh
, struct stripe_head_state
*s
)
3994 struct r5conf
*conf
= sh
->raid_conf
;
3995 int disks
= sh
->disks
;
3998 int do_recovery
= 0;
4000 memset(s
, 0, sizeof(*s
));
4002 s
->expanding
= test_bit(STRIPE_EXPAND_SOURCE
, &sh
->state
) && !sh
->batch_head
;
4003 s
->expanded
= test_bit(STRIPE_EXPAND_READY
, &sh
->state
) && !sh
->batch_head
;
4004 s
->failed_num
[0] = -1;
4005 s
->failed_num
[1] = -1;
4007 /* Now to look around and see what can be done */
4009 for (i
=disks
; i
--; ) {
4010 struct md_rdev
*rdev
;
4017 pr_debug("check %d: state 0x%lx read %p write %p written %p\n",
4019 dev
->toread
, dev
->towrite
, dev
->written
);
4020 /* maybe we can reply to a read
4022 * new wantfill requests are only permitted while
4023 * ops_complete_biofill is guaranteed to be inactive
4025 if (test_bit(R5_UPTODATE
, &dev
->flags
) && dev
->toread
&&
4026 !test_bit(STRIPE_BIOFILL_RUN
, &sh
->state
))
4027 set_bit(R5_Wantfill
, &dev
->flags
);
4029 /* now count some things */
4030 if (test_bit(R5_LOCKED
, &dev
->flags
))
4032 if (test_bit(R5_UPTODATE
, &dev
->flags
))
4034 if (test_bit(R5_Wantcompute
, &dev
->flags
)) {
4036 BUG_ON(s
->compute
> 2);
4039 if (test_bit(R5_Wantfill
, &dev
->flags
))
4041 else if (dev
->toread
)
4045 if (!test_bit(R5_OVERWRITE
, &dev
->flags
))
4050 /* Prefer to use the replacement for reads, but only
4051 * if it is recovered enough and has no bad blocks.
4053 rdev
= rcu_dereference(conf
->disks
[i
].replacement
);
4054 if (rdev
&& !test_bit(Faulty
, &rdev
->flags
) &&
4055 rdev
->recovery_offset
>= sh
->sector
+ STRIPE_SECTORS
&&
4056 !is_badblock(rdev
, sh
->sector
, STRIPE_SECTORS
,
4057 &first_bad
, &bad_sectors
))
4058 set_bit(R5_ReadRepl
, &dev
->flags
);
4061 set_bit(R5_NeedReplace
, &dev
->flags
);
4062 rdev
= rcu_dereference(conf
->disks
[i
].rdev
);
4063 clear_bit(R5_ReadRepl
, &dev
->flags
);
4065 if (rdev
&& test_bit(Faulty
, &rdev
->flags
))
4068 is_bad
= is_badblock(rdev
, sh
->sector
, STRIPE_SECTORS
,
4069 &first_bad
, &bad_sectors
);
4070 if (s
->blocked_rdev
== NULL
4071 && (test_bit(Blocked
, &rdev
->flags
)
4074 set_bit(BlockedBadBlocks
,
4076 s
->blocked_rdev
= rdev
;
4077 atomic_inc(&rdev
->nr_pending
);
4080 clear_bit(R5_Insync
, &dev
->flags
);
4084 /* also not in-sync */
4085 if (!test_bit(WriteErrorSeen
, &rdev
->flags
) &&
4086 test_bit(R5_UPTODATE
, &dev
->flags
)) {
4087 /* treat as in-sync, but with a read error
4088 * which we can now try to correct
4090 set_bit(R5_Insync
, &dev
->flags
);
4091 set_bit(R5_ReadError
, &dev
->flags
);
4093 } else if (test_bit(In_sync
, &rdev
->flags
))
4094 set_bit(R5_Insync
, &dev
->flags
);
4095 else if (sh
->sector
+ STRIPE_SECTORS
<= rdev
->recovery_offset
)
4096 /* in sync if before recovery_offset */
4097 set_bit(R5_Insync
, &dev
->flags
);
4098 else if (test_bit(R5_UPTODATE
, &dev
->flags
) &&
4099 test_bit(R5_Expanded
, &dev
->flags
))
4100 /* If we've reshaped into here, we assume it is Insync.
4101 * We will shortly update recovery_offset to make
4104 set_bit(R5_Insync
, &dev
->flags
);
4106 if (test_bit(R5_WriteError
, &dev
->flags
)) {
4107 /* This flag does not apply to '.replacement'
4108 * only to .rdev, so make sure to check that*/
4109 struct md_rdev
*rdev2
= rcu_dereference(
4110 conf
->disks
[i
].rdev
);
4112 clear_bit(R5_Insync
, &dev
->flags
);
4113 if (rdev2
&& !test_bit(Faulty
, &rdev2
->flags
)) {
4114 s
->handle_bad_blocks
= 1;
4115 atomic_inc(&rdev2
->nr_pending
);
4117 clear_bit(R5_WriteError
, &dev
->flags
);
4119 if (test_bit(R5_MadeGood
, &dev
->flags
)) {
4120 /* This flag does not apply to '.replacement'
4121 * only to .rdev, so make sure to check that*/
4122 struct md_rdev
*rdev2
= rcu_dereference(
4123 conf
->disks
[i
].rdev
);
4124 if (rdev2
&& !test_bit(Faulty
, &rdev2
->flags
)) {
4125 s
->handle_bad_blocks
= 1;
4126 atomic_inc(&rdev2
->nr_pending
);
4128 clear_bit(R5_MadeGood
, &dev
->flags
);
4130 if (test_bit(R5_MadeGoodRepl
, &dev
->flags
)) {
4131 struct md_rdev
*rdev2
= rcu_dereference(
4132 conf
->disks
[i
].replacement
);
4133 if (rdev2
&& !test_bit(Faulty
, &rdev2
->flags
)) {
4134 s
->handle_bad_blocks
= 1;
4135 atomic_inc(&rdev2
->nr_pending
);
4137 clear_bit(R5_MadeGoodRepl
, &dev
->flags
);
4139 if (!test_bit(R5_Insync
, &dev
->flags
)) {
4140 /* The ReadError flag will just be confusing now */
4141 clear_bit(R5_ReadError
, &dev
->flags
);
4142 clear_bit(R5_ReWrite
, &dev
->flags
);
4144 if (test_bit(R5_ReadError
, &dev
->flags
))
4145 clear_bit(R5_Insync
, &dev
->flags
);
4146 if (!test_bit(R5_Insync
, &dev
->flags
)) {
4148 s
->failed_num
[s
->failed
] = i
;
4150 if (rdev
&& !test_bit(Faulty
, &rdev
->flags
))
4154 if (test_bit(STRIPE_SYNCING
, &sh
->state
)) {
4155 /* If there is a failed device being replaced,
4156 * we must be recovering.
4157 * else if we are after recovery_cp, we must be syncing
4158 * else if MD_RECOVERY_REQUESTED is set, we also are syncing.
4159 * else we can only be replacing
4160 * sync and recovery both need to read all devices, and so
4161 * use the same flag.
4164 sh
->sector
>= conf
->mddev
->recovery_cp
||
4165 test_bit(MD_RECOVERY_REQUESTED
, &(conf
->mddev
->recovery
)))
4173 static int clear_batch_ready(struct stripe_head
*sh
)
4175 struct stripe_head
*tmp
;
4176 if (!test_and_clear_bit(STRIPE_BATCH_READY
, &sh
->state
))
4178 spin_lock(&sh
->stripe_lock
);
4179 if (!sh
->batch_head
) {
4180 spin_unlock(&sh
->stripe_lock
);
4185 * this stripe could be added to a batch list before we check
4186 * BATCH_READY, skips it
4188 if (sh
->batch_head
!= sh
) {
4189 spin_unlock(&sh
->stripe_lock
);
4192 spin_lock(&sh
->batch_lock
);
4193 list_for_each_entry(tmp
, &sh
->batch_list
, batch_list
)
4194 clear_bit(STRIPE_BATCH_READY
, &tmp
->state
);
4195 spin_unlock(&sh
->batch_lock
);
4196 spin_unlock(&sh
->stripe_lock
);
4199 * BATCH_READY is cleared, no new stripes can be added.
4200 * batch_list can be accessed without lock
4205 static void check_break_stripe_batch_list(struct stripe_head
*sh
)
4207 struct stripe_head
*head_sh
, *next
;
4210 if (!test_and_clear_bit(STRIPE_BATCH_ERR
, &sh
->state
))
4215 list_for_each_entry_safe(sh
, next
, &head_sh
->batch_list
, batch_list
) {
4217 list_del_init(&sh
->batch_list
);
4219 set_mask_bits(&sh
->state
, ~STRIPE_EXPAND_SYNC_FLAG
,
4220 head_sh
->state
& ~((1 << STRIPE_ACTIVE
) |
4221 (1 << STRIPE_PREREAD_ACTIVE
) |
4222 (1 << STRIPE_DEGRADED
) |
4223 STRIPE_EXPAND_SYNC_FLAG
));
4224 sh
->check_state
= head_sh
->check_state
;
4225 sh
->reconstruct_state
= head_sh
->reconstruct_state
;
4226 for (i
= 0; i
< sh
->disks
; i
++)
4227 sh
->dev
[i
].flags
= head_sh
->dev
[i
].flags
&
4228 (~((1 << R5_WriteError
) | (1 << R5_Overlap
)));
4230 spin_lock_irq(&sh
->stripe_lock
);
4231 sh
->batch_head
= NULL
;
4232 spin_unlock_irq(&sh
->stripe_lock
);
4234 set_bit(STRIPE_HANDLE
, &sh
->state
);
4239 static void handle_stripe(struct stripe_head
*sh
)
4241 struct stripe_head_state s
;
4242 struct r5conf
*conf
= sh
->raid_conf
;
4245 int disks
= sh
->disks
;
4246 struct r5dev
*pdev
, *qdev
;
4248 clear_bit(STRIPE_HANDLE
, &sh
->state
);
4249 if (test_and_set_bit_lock(STRIPE_ACTIVE
, &sh
->state
)) {
4250 /* already being handled, ensure it gets handled
4251 * again when current action finishes */
4252 set_bit(STRIPE_HANDLE
, &sh
->state
);
4256 if (clear_batch_ready(sh
) ) {
4257 clear_bit_unlock(STRIPE_ACTIVE
, &sh
->state
);
4261 check_break_stripe_batch_list(sh
);
4263 if (test_bit(STRIPE_SYNC_REQUESTED
, &sh
->state
) && !sh
->batch_head
) {
4264 spin_lock(&sh
->stripe_lock
);
4265 /* Cannot process 'sync' concurrently with 'discard' */
4266 if (!test_bit(STRIPE_DISCARD
, &sh
->state
) &&
4267 test_and_clear_bit(STRIPE_SYNC_REQUESTED
, &sh
->state
)) {
4268 set_bit(STRIPE_SYNCING
, &sh
->state
);
4269 clear_bit(STRIPE_INSYNC
, &sh
->state
);
4270 clear_bit(STRIPE_REPLACED
, &sh
->state
);
4272 spin_unlock(&sh
->stripe_lock
);
4274 clear_bit(STRIPE_DELAYED
, &sh
->state
);
4276 pr_debug("handling stripe %llu, state=%#lx cnt=%d, "
4277 "pd_idx=%d, qd_idx=%d\n, check:%d, reconstruct:%d\n",
4278 (unsigned long long)sh
->sector
, sh
->state
,
4279 atomic_read(&sh
->count
), sh
->pd_idx
, sh
->qd_idx
,
4280 sh
->check_state
, sh
->reconstruct_state
);
4282 analyse_stripe(sh
, &s
);
4284 if (s
.handle_bad_blocks
) {
4285 set_bit(STRIPE_HANDLE
, &sh
->state
);
4289 if (unlikely(s
.blocked_rdev
)) {
4290 if (s
.syncing
|| s
.expanding
|| s
.expanded
||
4291 s
.replacing
|| s
.to_write
|| s
.written
) {
4292 set_bit(STRIPE_HANDLE
, &sh
->state
);
4295 /* There is nothing for the blocked_rdev to block */
4296 rdev_dec_pending(s
.blocked_rdev
, conf
->mddev
);
4297 s
.blocked_rdev
= NULL
;
4300 if (s
.to_fill
&& !test_bit(STRIPE_BIOFILL_RUN
, &sh
->state
)) {
4301 set_bit(STRIPE_OP_BIOFILL
, &s
.ops_request
);
4302 set_bit(STRIPE_BIOFILL_RUN
, &sh
->state
);
4305 pr_debug("locked=%d uptodate=%d to_read=%d"
4306 " to_write=%d failed=%d failed_num=%d,%d\n",
4307 s
.locked
, s
.uptodate
, s
.to_read
, s
.to_write
, s
.failed
,
4308 s
.failed_num
[0], s
.failed_num
[1]);
4309 /* check if the array has lost more than max_degraded devices and,
4310 * if so, some requests might need to be failed.
4312 if (s
.failed
> conf
->max_degraded
) {
4313 sh
->check_state
= 0;
4314 sh
->reconstruct_state
= 0;
4315 if (s
.to_read
+s
.to_write
+s
.written
)
4316 handle_failed_stripe(conf
, sh
, &s
, disks
, &s
.return_bi
);
4317 if (s
.syncing
+ s
.replacing
)
4318 handle_failed_sync(conf
, sh
, &s
);
4321 /* Now we check to see if any write operations have recently
4325 if (sh
->reconstruct_state
== reconstruct_state_prexor_drain_result
)
4327 if (sh
->reconstruct_state
== reconstruct_state_drain_result
||
4328 sh
->reconstruct_state
== reconstruct_state_prexor_drain_result
) {
4329 sh
->reconstruct_state
= reconstruct_state_idle
;
4331 /* All the 'written' buffers and the parity block are ready to
4332 * be written back to disk
4334 BUG_ON(!test_bit(R5_UPTODATE
, &sh
->dev
[sh
->pd_idx
].flags
) &&
4335 !test_bit(R5_Discard
, &sh
->dev
[sh
->pd_idx
].flags
));
4336 BUG_ON(sh
->qd_idx
>= 0 &&
4337 !test_bit(R5_UPTODATE
, &sh
->dev
[sh
->qd_idx
].flags
) &&
4338 !test_bit(R5_Discard
, &sh
->dev
[sh
->qd_idx
].flags
));
4339 for (i
= disks
; i
--; ) {
4340 struct r5dev
*dev
= &sh
->dev
[i
];
4341 if (test_bit(R5_LOCKED
, &dev
->flags
) &&
4342 (i
== sh
->pd_idx
|| i
== sh
->qd_idx
||
4344 pr_debug("Writing block %d\n", i
);
4345 set_bit(R5_Wantwrite
, &dev
->flags
);
4350 if (!test_bit(R5_Insync
, &dev
->flags
) ||
4351 ((i
== sh
->pd_idx
|| i
== sh
->qd_idx
) &&
4353 set_bit(STRIPE_INSYNC
, &sh
->state
);
4356 if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
4357 s
.dec_preread_active
= 1;
4361 * might be able to return some write requests if the parity blocks
4362 * are safe, or on a failed drive
4364 pdev
= &sh
->dev
[sh
->pd_idx
];
4365 s
.p_failed
= (s
.failed
>= 1 && s
.failed_num
[0] == sh
->pd_idx
)
4366 || (s
.failed
>= 2 && s
.failed_num
[1] == sh
->pd_idx
);
4367 qdev
= &sh
->dev
[sh
->qd_idx
];
4368 s
.q_failed
= (s
.failed
>= 1 && s
.failed_num
[0] == sh
->qd_idx
)
4369 || (s
.failed
>= 2 && s
.failed_num
[1] == sh
->qd_idx
)
4373 (s
.p_failed
|| ((test_bit(R5_Insync
, &pdev
->flags
)
4374 && !test_bit(R5_LOCKED
, &pdev
->flags
)
4375 && (test_bit(R5_UPTODATE
, &pdev
->flags
) ||
4376 test_bit(R5_Discard
, &pdev
->flags
))))) &&
4377 (s
.q_failed
|| ((test_bit(R5_Insync
, &qdev
->flags
)
4378 && !test_bit(R5_LOCKED
, &qdev
->flags
)
4379 && (test_bit(R5_UPTODATE
, &qdev
->flags
) ||
4380 test_bit(R5_Discard
, &qdev
->flags
))))))
4381 handle_stripe_clean_event(conf
, sh
, disks
, &s
.return_bi
);
4383 /* Now we might consider reading some blocks, either to check/generate
4384 * parity, or to satisfy requests
4385 * or to load a block that is being partially written.
4387 if (s
.to_read
|| s
.non_overwrite
4388 || (conf
->level
== 6 && s
.to_write
&& s
.failed
)
4389 || (s
.syncing
&& (s
.uptodate
+ s
.compute
< disks
))
4392 handle_stripe_fill(sh
, &s
, disks
);
4394 /* Now to consider new write requests and what else, if anything
4395 * should be read. We do not handle new writes when:
4396 * 1/ A 'write' operation (copy+xor) is already in flight.
4397 * 2/ A 'check' operation is in flight, as it may clobber the parity
4400 if (s
.to_write
&& !sh
->reconstruct_state
&& !sh
->check_state
)
4401 handle_stripe_dirtying(conf
, sh
, &s
, disks
);
4403 /* maybe we need to check and possibly fix the parity for this stripe
4404 * Any reads will already have been scheduled, so we just see if enough
4405 * data is available. The parity check is held off while parity
4406 * dependent operations are in flight.
4408 if (sh
->check_state
||
4409 (s
.syncing
&& s
.locked
== 0 &&
4410 !test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
) &&
4411 !test_bit(STRIPE_INSYNC
, &sh
->state
))) {
4412 if (conf
->level
== 6)
4413 handle_parity_checks6(conf
, sh
, &s
, disks
);
4415 handle_parity_checks5(conf
, sh
, &s
, disks
);
4418 if ((s
.replacing
|| s
.syncing
) && s
.locked
== 0
4419 && !test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
)
4420 && !test_bit(STRIPE_REPLACED
, &sh
->state
)) {
4421 /* Write out to replacement devices where possible */
4422 for (i
= 0; i
< conf
->raid_disks
; i
++)
4423 if (test_bit(R5_NeedReplace
, &sh
->dev
[i
].flags
)) {
4424 WARN_ON(!test_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
));
4425 set_bit(R5_WantReplace
, &sh
->dev
[i
].flags
);
4426 set_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
4430 set_bit(STRIPE_INSYNC
, &sh
->state
);
4431 set_bit(STRIPE_REPLACED
, &sh
->state
);
4433 if ((s
.syncing
|| s
.replacing
) && s
.locked
== 0 &&
4434 !test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
) &&
4435 test_bit(STRIPE_INSYNC
, &sh
->state
)) {
4436 md_done_sync(conf
->mddev
, STRIPE_SECTORS
, 1);
4437 clear_bit(STRIPE_SYNCING
, &sh
->state
);
4438 if (test_and_clear_bit(R5_Overlap
, &sh
->dev
[sh
->pd_idx
].flags
))
4439 wake_up(&conf
->wait_for_overlap
);
4442 /* If the failed drives are just a ReadError, then we might need
4443 * to progress the repair/check process
4445 if (s
.failed
<= conf
->max_degraded
&& !conf
->mddev
->ro
)
4446 for (i
= 0; i
< s
.failed
; i
++) {
4447 struct r5dev
*dev
= &sh
->dev
[s
.failed_num
[i
]];
4448 if (test_bit(R5_ReadError
, &dev
->flags
)
4449 && !test_bit(R5_LOCKED
, &dev
->flags
)
4450 && test_bit(R5_UPTODATE
, &dev
->flags
)
4452 if (!test_bit(R5_ReWrite
, &dev
->flags
)) {
4453 set_bit(R5_Wantwrite
, &dev
->flags
);
4454 set_bit(R5_ReWrite
, &dev
->flags
);
4455 set_bit(R5_LOCKED
, &dev
->flags
);
4458 /* let's read it back */
4459 set_bit(R5_Wantread
, &dev
->flags
);
4460 set_bit(R5_LOCKED
, &dev
->flags
);
4466 /* Finish reconstruct operations initiated by the expansion process */
4467 if (sh
->reconstruct_state
== reconstruct_state_result
) {
4468 struct stripe_head
*sh_src
4469 = get_active_stripe(conf
, sh
->sector
, 1, 1, 1);
4470 if (sh_src
&& test_bit(STRIPE_EXPAND_SOURCE
, &sh_src
->state
)) {
4471 /* sh cannot be written until sh_src has been read.
4472 * so arrange for sh to be delayed a little
4474 set_bit(STRIPE_DELAYED
, &sh
->state
);
4475 set_bit(STRIPE_HANDLE
, &sh
->state
);
4476 if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE
,
4478 atomic_inc(&conf
->preread_active_stripes
);
4479 release_stripe(sh_src
);
4483 release_stripe(sh_src
);
4485 sh
->reconstruct_state
= reconstruct_state_idle
;
4486 clear_bit(STRIPE_EXPANDING
, &sh
->state
);
4487 for (i
= conf
->raid_disks
; i
--; ) {
4488 set_bit(R5_Wantwrite
, &sh
->dev
[i
].flags
);
4489 set_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
4494 if (s
.expanded
&& test_bit(STRIPE_EXPANDING
, &sh
->state
) &&
4495 !sh
->reconstruct_state
) {
4496 /* Need to write out all blocks after computing parity */
4497 sh
->disks
= conf
->raid_disks
;
4498 stripe_set_idx(sh
->sector
, conf
, 0, sh
);
4499 schedule_reconstruction(sh
, &s
, 1, 1);
4500 } else if (s
.expanded
&& !sh
->reconstruct_state
&& s
.locked
== 0) {
4501 clear_bit(STRIPE_EXPAND_READY
, &sh
->state
);
4502 atomic_dec(&conf
->reshape_stripes
);
4503 wake_up(&conf
->wait_for_overlap
);
4504 md_done_sync(conf
->mddev
, STRIPE_SECTORS
, 1);
4507 if (s
.expanding
&& s
.locked
== 0 &&
4508 !test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
))
4509 handle_stripe_expansion(conf
, sh
);
4512 /* wait for this device to become unblocked */
4513 if (unlikely(s
.blocked_rdev
)) {
4514 if (conf
->mddev
->external
)
4515 md_wait_for_blocked_rdev(s
.blocked_rdev
,
4518 /* Internal metadata will immediately
4519 * be written by raid5d, so we don't
4520 * need to wait here.
4522 rdev_dec_pending(s
.blocked_rdev
,
4526 if (s
.handle_bad_blocks
)
4527 for (i
= disks
; i
--; ) {
4528 struct md_rdev
*rdev
;
4529 struct r5dev
*dev
= &sh
->dev
[i
];
4530 if (test_and_clear_bit(R5_WriteError
, &dev
->flags
)) {
4531 /* We own a safe reference to the rdev */
4532 rdev
= conf
->disks
[i
].rdev
;
4533 if (!rdev_set_badblocks(rdev
, sh
->sector
,
4535 md_error(conf
->mddev
, rdev
);
4536 rdev_dec_pending(rdev
, conf
->mddev
);
4538 if (test_and_clear_bit(R5_MadeGood
, &dev
->flags
)) {
4539 rdev
= conf
->disks
[i
].rdev
;
4540 rdev_clear_badblocks(rdev
, sh
->sector
,
4542 rdev_dec_pending(rdev
, conf
->mddev
);
4544 if (test_and_clear_bit(R5_MadeGoodRepl
, &dev
->flags
)) {
4545 rdev
= conf
->disks
[i
].replacement
;
4547 /* rdev have been moved down */
4548 rdev
= conf
->disks
[i
].rdev
;
4549 rdev_clear_badblocks(rdev
, sh
->sector
,
4551 rdev_dec_pending(rdev
, conf
->mddev
);
4556 raid_run_ops(sh
, s
.ops_request
);
4560 if (s
.dec_preread_active
) {
4561 /* We delay this until after ops_run_io so that if make_request
4562 * is waiting on a flush, it won't continue until the writes
4563 * have actually been submitted.
4565 atomic_dec(&conf
->preread_active_stripes
);
4566 if (atomic_read(&conf
->preread_active_stripes
) <
4568 md_wakeup_thread(conf
->mddev
->thread
);
4571 return_io(s
.return_bi
);
4573 clear_bit_unlock(STRIPE_ACTIVE
, &sh
->state
);
4576 static void raid5_activate_delayed(struct r5conf
*conf
)
4578 if (atomic_read(&conf
->preread_active_stripes
) < IO_THRESHOLD
) {
4579 while (!list_empty(&conf
->delayed_list
)) {
4580 struct list_head
*l
= conf
->delayed_list
.next
;
4581 struct stripe_head
*sh
;
4582 sh
= list_entry(l
, struct stripe_head
, lru
);
4584 clear_bit(STRIPE_DELAYED
, &sh
->state
);
4585 if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
4586 atomic_inc(&conf
->preread_active_stripes
);
4587 list_add_tail(&sh
->lru
, &conf
->hold_list
);
4588 raid5_wakeup_stripe_thread(sh
);
4593 static void activate_bit_delay(struct r5conf
*conf
,
4594 struct list_head
*temp_inactive_list
)
4596 /* device_lock is held */
4597 struct list_head head
;
4598 list_add(&head
, &conf
->bitmap_list
);
4599 list_del_init(&conf
->bitmap_list
);
4600 while (!list_empty(&head
)) {
4601 struct stripe_head
*sh
= list_entry(head
.next
, struct stripe_head
, lru
);
4603 list_del_init(&sh
->lru
);
4604 atomic_inc(&sh
->count
);
4605 hash
= sh
->hash_lock_index
;
4606 __release_stripe(conf
, sh
, &temp_inactive_list
[hash
]);
4610 static int raid5_congested(struct mddev
*mddev
, int bits
)
4612 struct r5conf
*conf
= mddev
->private;
4614 /* No difference between reads and writes. Just check
4615 * how busy the stripe_cache is
4618 if (test_bit(R5_INACTIVE_BLOCKED
, &conf
->cache_state
))
4622 if (atomic_read(&conf
->empty_inactive_list_nr
))
4628 /* We want read requests to align with chunks where possible,
4629 * but write requests don't need to.
4631 static int raid5_mergeable_bvec(struct mddev
*mddev
,
4632 struct bvec_merge_data
*bvm
,
4633 struct bio_vec
*biovec
)
4635 sector_t sector
= bvm
->bi_sector
+ get_start_sect(bvm
->bi_bdev
);
4637 unsigned int chunk_sectors
= mddev
->chunk_sectors
;
4638 unsigned int bio_sectors
= bvm
->bi_size
>> 9;
4641 * always allow writes to be mergeable, read as well if array
4642 * is degraded as we'll go through stripe cache anyway.
4644 if ((bvm
->bi_rw
& 1) == WRITE
|| mddev
->degraded
)
4645 return biovec
->bv_len
;
4647 if (mddev
->new_chunk_sectors
< mddev
->chunk_sectors
)
4648 chunk_sectors
= mddev
->new_chunk_sectors
;
4649 max
= (chunk_sectors
- ((sector
& (chunk_sectors
- 1)) + bio_sectors
)) << 9;
4650 if (max
< 0) max
= 0;
4651 if (max
<= biovec
->bv_len
&& bio_sectors
== 0)
4652 return biovec
->bv_len
;
4657 static int in_chunk_boundary(struct mddev
*mddev
, struct bio
*bio
)
4659 sector_t sector
= bio
->bi_iter
.bi_sector
+ get_start_sect(bio
->bi_bdev
);
4660 unsigned int chunk_sectors
= mddev
->chunk_sectors
;
4661 unsigned int bio_sectors
= bio_sectors(bio
);
4663 if (mddev
->new_chunk_sectors
< mddev
->chunk_sectors
)
4664 chunk_sectors
= mddev
->new_chunk_sectors
;
4665 return chunk_sectors
>=
4666 ((sector
& (chunk_sectors
- 1)) + bio_sectors
);
4670 * add bio to the retry LIFO ( in O(1) ... we are in interrupt )
4671 * later sampled by raid5d.
4673 static void add_bio_to_retry(struct bio
*bi
,struct r5conf
*conf
)
4675 unsigned long flags
;
4677 spin_lock_irqsave(&conf
->device_lock
, flags
);
4679 bi
->bi_next
= conf
->retry_read_aligned_list
;
4680 conf
->retry_read_aligned_list
= bi
;
4682 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
4683 md_wakeup_thread(conf
->mddev
->thread
);
4686 static struct bio
*remove_bio_from_retry(struct r5conf
*conf
)
4690 bi
= conf
->retry_read_aligned
;
4692 conf
->retry_read_aligned
= NULL
;
4695 bi
= conf
->retry_read_aligned_list
;
4697 conf
->retry_read_aligned_list
= bi
->bi_next
;
4700 * this sets the active strip count to 1 and the processed
4701 * strip count to zero (upper 8 bits)
4703 raid5_set_bi_stripes(bi
, 1); /* biased count of active stripes */
4710 * The "raid5_align_endio" should check if the read succeeded and if it
4711 * did, call bio_endio on the original bio (having bio_put the new bio
4713 * If the read failed..
4715 static void raid5_align_endio(struct bio
*bi
, int error
)
4717 struct bio
* raid_bi
= bi
->bi_private
;
4718 struct mddev
*mddev
;
4719 struct r5conf
*conf
;
4720 int uptodate
= test_bit(BIO_UPTODATE
, &bi
->bi_flags
);
4721 struct md_rdev
*rdev
;
4725 rdev
= (void*)raid_bi
->bi_next
;
4726 raid_bi
->bi_next
= NULL
;
4727 mddev
= rdev
->mddev
;
4728 conf
= mddev
->private;
4730 rdev_dec_pending(rdev
, conf
->mddev
);
4732 if (!error
&& uptodate
) {
4733 trace_block_bio_complete(bdev_get_queue(raid_bi
->bi_bdev
),
4735 bio_endio(raid_bi
, 0);
4736 if (atomic_dec_and_test(&conf
->active_aligned_reads
))
4737 wake_up(&conf
->wait_for_stripe
);
4741 pr_debug("raid5_align_endio : io error...handing IO for a retry\n");
4743 add_bio_to_retry(raid_bi
, conf
);
4746 static int bio_fits_rdev(struct bio
*bi
)
4748 struct request_queue
*q
= bdev_get_queue(bi
->bi_bdev
);
4750 if (bio_sectors(bi
) > queue_max_sectors(q
))
4752 blk_recount_segments(q
, bi
);
4753 if (bi
->bi_phys_segments
> queue_max_segments(q
))
4756 if (q
->merge_bvec_fn
)
4757 /* it's too hard to apply the merge_bvec_fn at this stage,
4765 static int chunk_aligned_read(struct mddev
*mddev
, struct bio
* raid_bio
)
4767 struct r5conf
*conf
= mddev
->private;
4769 struct bio
* align_bi
;
4770 struct md_rdev
*rdev
;
4771 sector_t end_sector
;
4773 if (!in_chunk_boundary(mddev
, raid_bio
)) {
4774 pr_debug("chunk_aligned_read : non aligned\n");
4778 * use bio_clone_mddev to make a copy of the bio
4780 align_bi
= bio_clone_mddev(raid_bio
, GFP_NOIO
, mddev
);
4784 * set bi_end_io to a new function, and set bi_private to the
4787 align_bi
->bi_end_io
= raid5_align_endio
;
4788 align_bi
->bi_private
= raid_bio
;
4792 align_bi
->bi_iter
.bi_sector
=
4793 raid5_compute_sector(conf
, raid_bio
->bi_iter
.bi_sector
,
4796 end_sector
= bio_end_sector(align_bi
);
4798 rdev
= rcu_dereference(conf
->disks
[dd_idx
].replacement
);
4799 if (!rdev
|| test_bit(Faulty
, &rdev
->flags
) ||
4800 rdev
->recovery_offset
< end_sector
) {
4801 rdev
= rcu_dereference(conf
->disks
[dd_idx
].rdev
);
4803 (test_bit(Faulty
, &rdev
->flags
) ||
4804 !(test_bit(In_sync
, &rdev
->flags
) ||
4805 rdev
->recovery_offset
>= end_sector
)))
4812 atomic_inc(&rdev
->nr_pending
);
4814 raid_bio
->bi_next
= (void*)rdev
;
4815 align_bi
->bi_bdev
= rdev
->bdev
;
4816 __clear_bit(BIO_SEG_VALID
, &align_bi
->bi_flags
);
4818 if (!bio_fits_rdev(align_bi
) ||
4819 is_badblock(rdev
, align_bi
->bi_iter
.bi_sector
,
4820 bio_sectors(align_bi
),
4821 &first_bad
, &bad_sectors
)) {
4822 /* too big in some way, or has a known bad block */
4824 rdev_dec_pending(rdev
, mddev
);
4828 /* No reshape active, so we can trust rdev->data_offset */
4829 align_bi
->bi_iter
.bi_sector
+= rdev
->data_offset
;
4831 spin_lock_irq(&conf
->device_lock
);
4832 wait_event_lock_irq(conf
->wait_for_stripe
,
4835 atomic_inc(&conf
->active_aligned_reads
);
4836 spin_unlock_irq(&conf
->device_lock
);
4839 trace_block_bio_remap(bdev_get_queue(align_bi
->bi_bdev
),
4840 align_bi
, disk_devt(mddev
->gendisk
),
4841 raid_bio
->bi_iter
.bi_sector
);
4842 generic_make_request(align_bi
);
4851 /* __get_priority_stripe - get the next stripe to process
4853 * Full stripe writes are allowed to pass preread active stripes up until
4854 * the bypass_threshold is exceeded. In general the bypass_count
4855 * increments when the handle_list is handled before the hold_list; however, it
4856 * will not be incremented when STRIPE_IO_STARTED is sampled set signifying a
4857 * stripe with in flight i/o. The bypass_count will be reset when the
4858 * head of the hold_list has changed, i.e. the head was promoted to the
4861 static struct stripe_head
*__get_priority_stripe(struct r5conf
*conf
, int group
)
4863 struct stripe_head
*sh
= NULL
, *tmp
;
4864 struct list_head
*handle_list
= NULL
;
4865 struct r5worker_group
*wg
= NULL
;
4867 if (conf
->worker_cnt_per_group
== 0) {
4868 handle_list
= &conf
->handle_list
;
4869 } else if (group
!= ANY_GROUP
) {
4870 handle_list
= &conf
->worker_groups
[group
].handle_list
;
4871 wg
= &conf
->worker_groups
[group
];
4874 for (i
= 0; i
< conf
->group_cnt
; i
++) {
4875 handle_list
= &conf
->worker_groups
[i
].handle_list
;
4876 wg
= &conf
->worker_groups
[i
];
4877 if (!list_empty(handle_list
))
4882 pr_debug("%s: handle: %s hold: %s full_writes: %d bypass_count: %d\n",
4884 list_empty(handle_list
) ? "empty" : "busy",
4885 list_empty(&conf
->hold_list
) ? "empty" : "busy",
4886 atomic_read(&conf
->pending_full_writes
), conf
->bypass_count
);
4888 if (!list_empty(handle_list
)) {
4889 sh
= list_entry(handle_list
->next
, typeof(*sh
), lru
);
4891 if (list_empty(&conf
->hold_list
))
4892 conf
->bypass_count
= 0;
4893 else if (!test_bit(STRIPE_IO_STARTED
, &sh
->state
)) {
4894 if (conf
->hold_list
.next
== conf
->last_hold
)
4895 conf
->bypass_count
++;
4897 conf
->last_hold
= conf
->hold_list
.next
;
4898 conf
->bypass_count
-= conf
->bypass_threshold
;
4899 if (conf
->bypass_count
< 0)
4900 conf
->bypass_count
= 0;
4903 } else if (!list_empty(&conf
->hold_list
) &&
4904 ((conf
->bypass_threshold
&&
4905 conf
->bypass_count
> conf
->bypass_threshold
) ||
4906 atomic_read(&conf
->pending_full_writes
) == 0)) {
4908 list_for_each_entry(tmp
, &conf
->hold_list
, lru
) {
4909 if (conf
->worker_cnt_per_group
== 0 ||
4910 group
== ANY_GROUP
||
4911 !cpu_online(tmp
->cpu
) ||
4912 cpu_to_group(tmp
->cpu
) == group
) {
4919 conf
->bypass_count
-= conf
->bypass_threshold
;
4920 if (conf
->bypass_count
< 0)
4921 conf
->bypass_count
= 0;
4933 list_del_init(&sh
->lru
);
4934 BUG_ON(atomic_inc_return(&sh
->count
) != 1);
4938 struct raid5_plug_cb
{
4939 struct blk_plug_cb cb
;
4940 struct list_head list
;
4941 struct list_head temp_inactive_list
[NR_STRIPE_HASH_LOCKS
];
4944 static void raid5_unplug(struct blk_plug_cb
*blk_cb
, bool from_schedule
)
4946 struct raid5_plug_cb
*cb
= container_of(
4947 blk_cb
, struct raid5_plug_cb
, cb
);
4948 struct stripe_head
*sh
;
4949 struct mddev
*mddev
= cb
->cb
.data
;
4950 struct r5conf
*conf
= mddev
->private;
4954 if (cb
->list
.next
&& !list_empty(&cb
->list
)) {
4955 spin_lock_irq(&conf
->device_lock
);
4956 while (!list_empty(&cb
->list
)) {
4957 sh
= list_first_entry(&cb
->list
, struct stripe_head
, lru
);
4958 list_del_init(&sh
->lru
);
4960 * avoid race release_stripe_plug() sees
4961 * STRIPE_ON_UNPLUG_LIST clear but the stripe
4962 * is still in our list
4964 smp_mb__before_atomic();
4965 clear_bit(STRIPE_ON_UNPLUG_LIST
, &sh
->state
);
4967 * STRIPE_ON_RELEASE_LIST could be set here. In that
4968 * case, the count is always > 1 here
4970 hash
= sh
->hash_lock_index
;
4971 __release_stripe(conf
, sh
, &cb
->temp_inactive_list
[hash
]);
4974 spin_unlock_irq(&conf
->device_lock
);
4976 release_inactive_stripe_list(conf
, cb
->temp_inactive_list
,
4977 NR_STRIPE_HASH_LOCKS
);
4979 trace_block_unplug(mddev
->queue
, cnt
, !from_schedule
);
4983 static void release_stripe_plug(struct mddev
*mddev
,
4984 struct stripe_head
*sh
)
4986 struct blk_plug_cb
*blk_cb
= blk_check_plugged(
4987 raid5_unplug
, mddev
,
4988 sizeof(struct raid5_plug_cb
));
4989 struct raid5_plug_cb
*cb
;
4996 cb
= container_of(blk_cb
, struct raid5_plug_cb
, cb
);
4998 if (cb
->list
.next
== NULL
) {
5000 INIT_LIST_HEAD(&cb
->list
);
5001 for (i
= 0; i
< NR_STRIPE_HASH_LOCKS
; i
++)
5002 INIT_LIST_HEAD(cb
->temp_inactive_list
+ i
);
5005 if (!test_and_set_bit(STRIPE_ON_UNPLUG_LIST
, &sh
->state
))
5006 list_add_tail(&sh
->lru
, &cb
->list
);
5011 static void make_discard_request(struct mddev
*mddev
, struct bio
*bi
)
5013 struct r5conf
*conf
= mddev
->private;
5014 sector_t logical_sector
, last_sector
;
5015 struct stripe_head
*sh
;
5019 if (mddev
->reshape_position
!= MaxSector
)
5020 /* Skip discard while reshape is happening */
5023 logical_sector
= bi
->bi_iter
.bi_sector
& ~((sector_t
)STRIPE_SECTORS
-1);
5024 last_sector
= bi
->bi_iter
.bi_sector
+ (bi
->bi_iter
.bi_size
>>9);
5027 bi
->bi_phys_segments
= 1; /* over-loaded to count active stripes */
5029 stripe_sectors
= conf
->chunk_sectors
*
5030 (conf
->raid_disks
- conf
->max_degraded
);
5031 logical_sector
= DIV_ROUND_UP_SECTOR_T(logical_sector
,
5033 sector_div(last_sector
, stripe_sectors
);
5035 logical_sector
*= conf
->chunk_sectors
;
5036 last_sector
*= conf
->chunk_sectors
;
5038 for (; logical_sector
< last_sector
;
5039 logical_sector
+= STRIPE_SECTORS
) {
5043 sh
= get_active_stripe(conf
, logical_sector
, 0, 0, 0);
5044 prepare_to_wait(&conf
->wait_for_overlap
, &w
,
5045 TASK_UNINTERRUPTIBLE
);
5046 set_bit(R5_Overlap
, &sh
->dev
[sh
->pd_idx
].flags
);
5047 if (test_bit(STRIPE_SYNCING
, &sh
->state
)) {
5052 clear_bit(R5_Overlap
, &sh
->dev
[sh
->pd_idx
].flags
);
5053 spin_lock_irq(&sh
->stripe_lock
);
5054 for (d
= 0; d
< conf
->raid_disks
; d
++) {
5055 if (d
== sh
->pd_idx
|| d
== sh
->qd_idx
)
5057 if (sh
->dev
[d
].towrite
|| sh
->dev
[d
].toread
) {
5058 set_bit(R5_Overlap
, &sh
->dev
[d
].flags
);
5059 spin_unlock_irq(&sh
->stripe_lock
);
5065 set_bit(STRIPE_DISCARD
, &sh
->state
);
5066 finish_wait(&conf
->wait_for_overlap
, &w
);
5067 sh
->overwrite_disks
= 0;
5068 for (d
= 0; d
< conf
->raid_disks
; d
++) {
5069 if (d
== sh
->pd_idx
|| d
== sh
->qd_idx
)
5071 sh
->dev
[d
].towrite
= bi
;
5072 set_bit(R5_OVERWRITE
, &sh
->dev
[d
].flags
);
5073 raid5_inc_bi_active_stripes(bi
);
5074 sh
->overwrite_disks
++;
5076 spin_unlock_irq(&sh
->stripe_lock
);
5077 if (conf
->mddev
->bitmap
) {
5079 d
< conf
->raid_disks
- conf
->max_degraded
;
5081 bitmap_startwrite(mddev
->bitmap
,
5085 sh
->bm_seq
= conf
->seq_flush
+ 1;
5086 set_bit(STRIPE_BIT_DELAY
, &sh
->state
);
5089 set_bit(STRIPE_HANDLE
, &sh
->state
);
5090 clear_bit(STRIPE_DELAYED
, &sh
->state
);
5091 if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
5092 atomic_inc(&conf
->preread_active_stripes
);
5093 release_stripe_plug(mddev
, sh
);
5096 remaining
= raid5_dec_bi_active_stripes(bi
);
5097 if (remaining
== 0) {
5098 md_write_end(mddev
);
5103 static void make_request(struct mddev
*mddev
, struct bio
* bi
)
5105 struct r5conf
*conf
= mddev
->private;
5107 sector_t new_sector
;
5108 sector_t logical_sector
, last_sector
;
5109 struct stripe_head
*sh
;
5110 const int rw
= bio_data_dir(bi
);
5115 if (unlikely(bi
->bi_rw
& REQ_FLUSH
)) {
5116 md_flush_request(mddev
, bi
);
5120 md_write_start(mddev
, bi
);
5123 * If array is degraded, better not do chunk aligned read because
5124 * later we might have to read it again in order to reconstruct
5125 * data on failed drives.
5127 if (rw
== READ
&& mddev
->degraded
== 0 &&
5128 mddev
->reshape_position
== MaxSector
&&
5129 chunk_aligned_read(mddev
,bi
))
5132 if (unlikely(bi
->bi_rw
& REQ_DISCARD
)) {
5133 make_discard_request(mddev
, bi
);
5137 logical_sector
= bi
->bi_iter
.bi_sector
& ~((sector_t
)STRIPE_SECTORS
-1);
5138 last_sector
= bio_end_sector(bi
);
5140 bi
->bi_phys_segments
= 1; /* over-loaded to count active stripes */
5142 prepare_to_wait(&conf
->wait_for_overlap
, &w
, TASK_UNINTERRUPTIBLE
);
5143 for (;logical_sector
< last_sector
; logical_sector
+= STRIPE_SECTORS
) {
5149 seq
= read_seqcount_begin(&conf
->gen_lock
);
5152 prepare_to_wait(&conf
->wait_for_overlap
, &w
,
5153 TASK_UNINTERRUPTIBLE
);
5154 if (unlikely(conf
->reshape_progress
!= MaxSector
)) {
5155 /* spinlock is needed as reshape_progress may be
5156 * 64bit on a 32bit platform, and so it might be
5157 * possible to see a half-updated value
5158 * Of course reshape_progress could change after
5159 * the lock is dropped, so once we get a reference
5160 * to the stripe that we think it is, we will have
5163 spin_lock_irq(&conf
->device_lock
);
5164 if (mddev
->reshape_backwards
5165 ? logical_sector
< conf
->reshape_progress
5166 : logical_sector
>= conf
->reshape_progress
) {
5169 if (mddev
->reshape_backwards
5170 ? logical_sector
< conf
->reshape_safe
5171 : logical_sector
>= conf
->reshape_safe
) {
5172 spin_unlock_irq(&conf
->device_lock
);
5178 spin_unlock_irq(&conf
->device_lock
);
5181 new_sector
= raid5_compute_sector(conf
, logical_sector
,
5184 pr_debug("raid456: make_request, sector %llu logical %llu\n",
5185 (unsigned long long)new_sector
,
5186 (unsigned long long)logical_sector
);
5188 sh
= get_active_stripe(conf
, new_sector
, previous
,
5189 (bi
->bi_rw
&RWA_MASK
), 0);
5191 if (unlikely(previous
)) {
5192 /* expansion might have moved on while waiting for a
5193 * stripe, so we must do the range check again.
5194 * Expansion could still move past after this
5195 * test, but as we are holding a reference to
5196 * 'sh', we know that if that happens,
5197 * STRIPE_EXPANDING will get set and the expansion
5198 * won't proceed until we finish with the stripe.
5201 spin_lock_irq(&conf
->device_lock
);
5202 if (mddev
->reshape_backwards
5203 ? logical_sector
>= conf
->reshape_progress
5204 : logical_sector
< conf
->reshape_progress
)
5205 /* mismatch, need to try again */
5207 spin_unlock_irq(&conf
->device_lock
);
5215 if (read_seqcount_retry(&conf
->gen_lock
, seq
)) {
5216 /* Might have got the wrong stripe_head
5224 logical_sector
>= mddev
->suspend_lo
&&
5225 logical_sector
< mddev
->suspend_hi
) {
5227 /* As the suspend_* range is controlled by
5228 * userspace, we want an interruptible
5231 flush_signals(current
);
5232 prepare_to_wait(&conf
->wait_for_overlap
,
5233 &w
, TASK_INTERRUPTIBLE
);
5234 if (logical_sector
>= mddev
->suspend_lo
&&
5235 logical_sector
< mddev
->suspend_hi
) {
5242 if (test_bit(STRIPE_EXPANDING
, &sh
->state
) ||
5243 !add_stripe_bio(sh
, bi
, dd_idx
, rw
, previous
)) {
5244 /* Stripe is busy expanding or
5245 * add failed due to overlap. Flush everything
5248 md_wakeup_thread(mddev
->thread
);
5254 set_bit(STRIPE_HANDLE
, &sh
->state
);
5255 clear_bit(STRIPE_DELAYED
, &sh
->state
);
5256 if ((!sh
->batch_head
|| sh
== sh
->batch_head
) &&
5257 (bi
->bi_rw
& REQ_SYNC
) &&
5258 !test_and_set_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
5259 atomic_inc(&conf
->preread_active_stripes
);
5260 release_stripe_plug(mddev
, sh
);
5262 /* cannot get stripe for read-ahead, just give-up */
5263 clear_bit(BIO_UPTODATE
, &bi
->bi_flags
);
5267 finish_wait(&conf
->wait_for_overlap
, &w
);
5269 remaining
= raid5_dec_bi_active_stripes(bi
);
5270 if (remaining
== 0) {
5273 md_write_end(mddev
);
5275 trace_block_bio_complete(bdev_get_queue(bi
->bi_bdev
),
5281 static sector_t
raid5_size(struct mddev
*mddev
, sector_t sectors
, int raid_disks
);
5283 static sector_t
reshape_request(struct mddev
*mddev
, sector_t sector_nr
, int *skipped
)
5285 /* reshaping is quite different to recovery/resync so it is
5286 * handled quite separately ... here.
5288 * On each call to sync_request, we gather one chunk worth of
5289 * destination stripes and flag them as expanding.
5290 * Then we find all the source stripes and request reads.
5291 * As the reads complete, handle_stripe will copy the data
5292 * into the destination stripe and release that stripe.
5294 struct r5conf
*conf
= mddev
->private;
5295 struct stripe_head
*sh
;
5296 sector_t first_sector
, last_sector
;
5297 int raid_disks
= conf
->previous_raid_disks
;
5298 int data_disks
= raid_disks
- conf
->max_degraded
;
5299 int new_data_disks
= conf
->raid_disks
- conf
->max_degraded
;
5302 sector_t writepos
, readpos
, safepos
;
5303 sector_t stripe_addr
;
5304 int reshape_sectors
;
5305 struct list_head stripes
;
5307 if (sector_nr
== 0) {
5308 /* If restarting in the middle, skip the initial sectors */
5309 if (mddev
->reshape_backwards
&&
5310 conf
->reshape_progress
< raid5_size(mddev
, 0, 0)) {
5311 sector_nr
= raid5_size(mddev
, 0, 0)
5312 - conf
->reshape_progress
;
5313 } else if (!mddev
->reshape_backwards
&&
5314 conf
->reshape_progress
> 0)
5315 sector_nr
= conf
->reshape_progress
;
5316 sector_div(sector_nr
, new_data_disks
);
5318 mddev
->curr_resync_completed
= sector_nr
;
5319 sysfs_notify(&mddev
->kobj
, NULL
, "sync_completed");
5325 /* We need to process a full chunk at a time.
5326 * If old and new chunk sizes differ, we need to process the
5329 if (mddev
->new_chunk_sectors
> mddev
->chunk_sectors
)
5330 reshape_sectors
= mddev
->new_chunk_sectors
;
5332 reshape_sectors
= mddev
->chunk_sectors
;
5334 /* We update the metadata at least every 10 seconds, or when
5335 * the data about to be copied would over-write the source of
5336 * the data at the front of the range. i.e. one new_stripe
5337 * along from reshape_progress new_maps to after where
5338 * reshape_safe old_maps to
5340 writepos
= conf
->reshape_progress
;
5341 sector_div(writepos
, new_data_disks
);
5342 readpos
= conf
->reshape_progress
;
5343 sector_div(readpos
, data_disks
);
5344 safepos
= conf
->reshape_safe
;
5345 sector_div(safepos
, data_disks
);
5346 if (mddev
->reshape_backwards
) {
5347 writepos
-= min_t(sector_t
, reshape_sectors
, writepos
);
5348 readpos
+= reshape_sectors
;
5349 safepos
+= reshape_sectors
;
5351 writepos
+= reshape_sectors
;
5352 readpos
-= min_t(sector_t
, reshape_sectors
, readpos
);
5353 safepos
-= min_t(sector_t
, reshape_sectors
, safepos
);
5356 /* Having calculated the 'writepos' possibly use it
5357 * to set 'stripe_addr' which is where we will write to.
5359 if (mddev
->reshape_backwards
) {
5360 BUG_ON(conf
->reshape_progress
== 0);
5361 stripe_addr
= writepos
;
5362 BUG_ON((mddev
->dev_sectors
&
5363 ~((sector_t
)reshape_sectors
- 1))
5364 - reshape_sectors
- stripe_addr
5367 BUG_ON(writepos
!= sector_nr
+ reshape_sectors
);
5368 stripe_addr
= sector_nr
;
5371 /* 'writepos' is the most advanced device address we might write.
5372 * 'readpos' is the least advanced device address we might read.
5373 * 'safepos' is the least address recorded in the metadata as having
5375 * If there is a min_offset_diff, these are adjusted either by
5376 * increasing the safepos/readpos if diff is negative, or
5377 * increasing writepos if diff is positive.
5378 * If 'readpos' is then behind 'writepos', there is no way that we can
5379 * ensure safety in the face of a crash - that must be done by userspace
5380 * making a backup of the data. So in that case there is no particular
5381 * rush to update metadata.
5382 * Otherwise if 'safepos' is behind 'writepos', then we really need to
5383 * update the metadata to advance 'safepos' to match 'readpos' so that
5384 * we can be safe in the event of a crash.
5385 * So we insist on updating metadata if safepos is behind writepos and
5386 * readpos is beyond writepos.
5387 * In any case, update the metadata every 10 seconds.
5388 * Maybe that number should be configurable, but I'm not sure it is
5389 * worth it.... maybe it could be a multiple of safemode_delay???
5391 if (conf
->min_offset_diff
< 0) {
5392 safepos
+= -conf
->min_offset_diff
;
5393 readpos
+= -conf
->min_offset_diff
;
5395 writepos
+= conf
->min_offset_diff
;
5397 if ((mddev
->reshape_backwards
5398 ? (safepos
> writepos
&& readpos
< writepos
)
5399 : (safepos
< writepos
&& readpos
> writepos
)) ||
5400 time_after(jiffies
, conf
->reshape_checkpoint
+ 10*HZ
)) {
5401 /* Cannot proceed until we've updated the superblock... */
5402 wait_event(conf
->wait_for_overlap
,
5403 atomic_read(&conf
->reshape_stripes
)==0
5404 || test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
));
5405 if (atomic_read(&conf
->reshape_stripes
) != 0)
5407 mddev
->reshape_position
= conf
->reshape_progress
;
5408 mddev
->curr_resync_completed
= sector_nr
;
5409 conf
->reshape_checkpoint
= jiffies
;
5410 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
5411 md_wakeup_thread(mddev
->thread
);
5412 wait_event(mddev
->sb_wait
, mddev
->flags
== 0 ||
5413 test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
));
5414 if (test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
))
5416 spin_lock_irq(&conf
->device_lock
);
5417 conf
->reshape_safe
= mddev
->reshape_position
;
5418 spin_unlock_irq(&conf
->device_lock
);
5419 wake_up(&conf
->wait_for_overlap
);
5420 sysfs_notify(&mddev
->kobj
, NULL
, "sync_completed");
5423 INIT_LIST_HEAD(&stripes
);
5424 for (i
= 0; i
< reshape_sectors
; i
+= STRIPE_SECTORS
) {
5426 int skipped_disk
= 0;
5427 sh
= get_active_stripe(conf
, stripe_addr
+i
, 0, 0, 1);
5428 set_bit(STRIPE_EXPANDING
, &sh
->state
);
5429 atomic_inc(&conf
->reshape_stripes
);
5430 /* If any of this stripe is beyond the end of the old
5431 * array, then we need to zero those blocks
5433 for (j
=sh
->disks
; j
--;) {
5435 if (j
== sh
->pd_idx
)
5437 if (conf
->level
== 6 &&
5440 s
= compute_blocknr(sh
, j
, 0);
5441 if (s
< raid5_size(mddev
, 0, 0)) {
5445 memset(page_address(sh
->dev
[j
].page
), 0, STRIPE_SIZE
);
5446 set_bit(R5_Expanded
, &sh
->dev
[j
].flags
);
5447 set_bit(R5_UPTODATE
, &sh
->dev
[j
].flags
);
5449 if (!skipped_disk
) {
5450 set_bit(STRIPE_EXPAND_READY
, &sh
->state
);
5451 set_bit(STRIPE_HANDLE
, &sh
->state
);
5453 list_add(&sh
->lru
, &stripes
);
5455 spin_lock_irq(&conf
->device_lock
);
5456 if (mddev
->reshape_backwards
)
5457 conf
->reshape_progress
-= reshape_sectors
* new_data_disks
;
5459 conf
->reshape_progress
+= reshape_sectors
* new_data_disks
;
5460 spin_unlock_irq(&conf
->device_lock
);
5461 /* Ok, those stripe are ready. We can start scheduling
5462 * reads on the source stripes.
5463 * The source stripes are determined by mapping the first and last
5464 * block on the destination stripes.
5467 raid5_compute_sector(conf
, stripe_addr
*(new_data_disks
),
5470 raid5_compute_sector(conf
, ((stripe_addr
+reshape_sectors
)
5471 * new_data_disks
- 1),
5473 if (last_sector
>= mddev
->dev_sectors
)
5474 last_sector
= mddev
->dev_sectors
- 1;
5475 while (first_sector
<= last_sector
) {
5476 sh
= get_active_stripe(conf
, first_sector
, 1, 0, 1);
5477 set_bit(STRIPE_EXPAND_SOURCE
, &sh
->state
);
5478 set_bit(STRIPE_HANDLE
, &sh
->state
);
5480 first_sector
+= STRIPE_SECTORS
;
5482 /* Now that the sources are clearly marked, we can release
5483 * the destination stripes
5485 while (!list_empty(&stripes
)) {
5486 sh
= list_entry(stripes
.next
, struct stripe_head
, lru
);
5487 list_del_init(&sh
->lru
);
5490 /* If this takes us to the resync_max point where we have to pause,
5491 * then we need to write out the superblock.
5493 sector_nr
+= reshape_sectors
;
5494 if ((sector_nr
- mddev
->curr_resync_completed
) * 2
5495 >= mddev
->resync_max
- mddev
->curr_resync_completed
) {
5496 /* Cannot proceed until we've updated the superblock... */
5497 wait_event(conf
->wait_for_overlap
,
5498 atomic_read(&conf
->reshape_stripes
) == 0
5499 || test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
));
5500 if (atomic_read(&conf
->reshape_stripes
) != 0)
5502 mddev
->reshape_position
= conf
->reshape_progress
;
5503 mddev
->curr_resync_completed
= sector_nr
;
5504 conf
->reshape_checkpoint
= jiffies
;
5505 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
5506 md_wakeup_thread(mddev
->thread
);
5507 wait_event(mddev
->sb_wait
,
5508 !test_bit(MD_CHANGE_DEVS
, &mddev
->flags
)
5509 || test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
));
5510 if (test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
))
5512 spin_lock_irq(&conf
->device_lock
);
5513 conf
->reshape_safe
= mddev
->reshape_position
;
5514 spin_unlock_irq(&conf
->device_lock
);
5515 wake_up(&conf
->wait_for_overlap
);
5516 sysfs_notify(&mddev
->kobj
, NULL
, "sync_completed");
5519 return reshape_sectors
;
5522 static inline sector_t
sync_request(struct mddev
*mddev
, sector_t sector_nr
, int *skipped
)
5524 struct r5conf
*conf
= mddev
->private;
5525 struct stripe_head
*sh
;
5526 sector_t max_sector
= mddev
->dev_sectors
;
5527 sector_t sync_blocks
;
5528 int still_degraded
= 0;
5531 if (sector_nr
>= max_sector
) {
5532 /* just being told to finish up .. nothing much to do */
5534 if (test_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
)) {
5539 if (mddev
->curr_resync
< max_sector
) /* aborted */
5540 bitmap_end_sync(mddev
->bitmap
, mddev
->curr_resync
,
5542 else /* completed sync */
5544 bitmap_close_sync(mddev
->bitmap
);
5549 /* Allow raid5_quiesce to complete */
5550 wait_event(conf
->wait_for_overlap
, conf
->quiesce
!= 2);
5552 if (test_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
))
5553 return reshape_request(mddev
, sector_nr
, skipped
);
5555 /* No need to check resync_max as we never do more than one
5556 * stripe, and as resync_max will always be on a chunk boundary,
5557 * if the check in md_do_sync didn't fire, there is no chance
5558 * of overstepping resync_max here
5561 /* if there is too many failed drives and we are trying
5562 * to resync, then assert that we are finished, because there is
5563 * nothing we can do.
5565 if (mddev
->degraded
>= conf
->max_degraded
&&
5566 test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
)) {
5567 sector_t rv
= mddev
->dev_sectors
- sector_nr
;
5571 if (!test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
) &&
5573 !bitmap_start_sync(mddev
->bitmap
, sector_nr
, &sync_blocks
, 1) &&
5574 sync_blocks
>= STRIPE_SECTORS
) {
5575 /* we can skip this block, and probably more */
5576 sync_blocks
/= STRIPE_SECTORS
;
5578 return sync_blocks
* STRIPE_SECTORS
; /* keep things rounded to whole stripes */
5581 bitmap_cond_end_sync(mddev
->bitmap
, sector_nr
);
5583 sh
= get_active_stripe(conf
, sector_nr
, 0, 1, 0);
5585 sh
= get_active_stripe(conf
, sector_nr
, 0, 0, 0);
5586 /* make sure we don't swamp the stripe cache if someone else
5587 * is trying to get access
5589 schedule_timeout_uninterruptible(1);
5591 /* Need to check if array will still be degraded after recovery/resync
5592 * Note in case of > 1 drive failures it's possible we're rebuilding
5593 * one drive while leaving another faulty drive in array.
5596 for (i
= 0; i
< conf
->raid_disks
; i
++) {
5597 struct md_rdev
*rdev
= ACCESS_ONCE(conf
->disks
[i
].rdev
);
5599 if (rdev
== NULL
|| test_bit(Faulty
, &rdev
->flags
))
5604 bitmap_start_sync(mddev
->bitmap
, sector_nr
, &sync_blocks
, still_degraded
);
5606 set_bit(STRIPE_SYNC_REQUESTED
, &sh
->state
);
5607 set_bit(STRIPE_HANDLE
, &sh
->state
);
5611 return STRIPE_SECTORS
;
5614 static int retry_aligned_read(struct r5conf
*conf
, struct bio
*raid_bio
)
5616 /* We may not be able to submit a whole bio at once as there
5617 * may not be enough stripe_heads available.
5618 * We cannot pre-allocate enough stripe_heads as we may need
5619 * more than exist in the cache (if we allow ever large chunks).
5620 * So we do one stripe head at a time and record in
5621 * ->bi_hw_segments how many have been done.
5623 * We *know* that this entire raid_bio is in one chunk, so
5624 * it will be only one 'dd_idx' and only need one call to raid5_compute_sector.
5626 struct stripe_head
*sh
;
5628 sector_t sector
, logical_sector
, last_sector
;
5633 logical_sector
= raid_bio
->bi_iter
.bi_sector
&
5634 ~((sector_t
)STRIPE_SECTORS
-1);
5635 sector
= raid5_compute_sector(conf
, logical_sector
,
5637 last_sector
= bio_end_sector(raid_bio
);
5639 for (; logical_sector
< last_sector
;
5640 logical_sector
+= STRIPE_SECTORS
,
5641 sector
+= STRIPE_SECTORS
,
5644 if (scnt
< raid5_bi_processed_stripes(raid_bio
))
5645 /* already done this stripe */
5648 sh
= get_active_stripe(conf
, sector
, 0, 1, 1);
5651 /* failed to get a stripe - must wait */
5652 raid5_set_bi_processed_stripes(raid_bio
, scnt
);
5653 conf
->retry_read_aligned
= raid_bio
;
5657 if (!add_stripe_bio(sh
, raid_bio
, dd_idx
, 0, 0)) {
5659 raid5_set_bi_processed_stripes(raid_bio
, scnt
);
5660 conf
->retry_read_aligned
= raid_bio
;
5664 set_bit(R5_ReadNoMerge
, &sh
->dev
[dd_idx
].flags
);
5669 remaining
= raid5_dec_bi_active_stripes(raid_bio
);
5670 if (remaining
== 0) {
5671 trace_block_bio_complete(bdev_get_queue(raid_bio
->bi_bdev
),
5673 bio_endio(raid_bio
, 0);
5675 if (atomic_dec_and_test(&conf
->active_aligned_reads
))
5676 wake_up(&conf
->wait_for_stripe
);
5680 static int handle_active_stripes(struct r5conf
*conf
, int group
,
5681 struct r5worker
*worker
,
5682 struct list_head
*temp_inactive_list
)
5684 struct stripe_head
*batch
[MAX_STRIPE_BATCH
], *sh
;
5685 int i
, batch_size
= 0, hash
;
5686 bool release_inactive
= false;
5688 while (batch_size
< MAX_STRIPE_BATCH
&&
5689 (sh
= __get_priority_stripe(conf
, group
)) != NULL
)
5690 batch
[batch_size
++] = sh
;
5692 if (batch_size
== 0) {
5693 for (i
= 0; i
< NR_STRIPE_HASH_LOCKS
; i
++)
5694 if (!list_empty(temp_inactive_list
+ i
))
5696 if (i
== NR_STRIPE_HASH_LOCKS
)
5698 release_inactive
= true;
5700 spin_unlock_irq(&conf
->device_lock
);
5702 release_inactive_stripe_list(conf
, temp_inactive_list
,
5703 NR_STRIPE_HASH_LOCKS
);
5705 if (release_inactive
) {
5706 spin_lock_irq(&conf
->device_lock
);
5710 for (i
= 0; i
< batch_size
; i
++)
5711 handle_stripe(batch
[i
]);
5715 spin_lock_irq(&conf
->device_lock
);
5716 for (i
= 0; i
< batch_size
; i
++) {
5717 hash
= batch
[i
]->hash_lock_index
;
5718 __release_stripe(conf
, batch
[i
], &temp_inactive_list
[hash
]);
5723 static void raid5_do_work(struct work_struct
*work
)
5725 struct r5worker
*worker
= container_of(work
, struct r5worker
, work
);
5726 struct r5worker_group
*group
= worker
->group
;
5727 struct r5conf
*conf
= group
->conf
;
5728 int group_id
= group
- conf
->worker_groups
;
5730 struct blk_plug plug
;
5732 pr_debug("+++ raid5worker active\n");
5734 blk_start_plug(&plug
);
5736 spin_lock_irq(&conf
->device_lock
);
5738 int batch_size
, released
;
5740 released
= release_stripe_list(conf
, worker
->temp_inactive_list
);
5742 batch_size
= handle_active_stripes(conf
, group_id
, worker
,
5743 worker
->temp_inactive_list
);
5744 worker
->working
= false;
5745 if (!batch_size
&& !released
)
5747 handled
+= batch_size
;
5749 pr_debug("%d stripes handled\n", handled
);
5751 spin_unlock_irq(&conf
->device_lock
);
5752 blk_finish_plug(&plug
);
5754 pr_debug("--- raid5worker inactive\n");
5758 * This is our raid5 kernel thread.
5760 * We scan the hash table for stripes which can be handled now.
5761 * During the scan, completed stripes are saved for us by the interrupt
5762 * handler, so that they will not have to wait for our next wakeup.
5764 static void raid5d(struct md_thread
*thread
)
5766 struct mddev
*mddev
= thread
->mddev
;
5767 struct r5conf
*conf
= mddev
->private;
5769 struct blk_plug plug
;
5771 pr_debug("+++ raid5d active\n");
5773 md_check_recovery(mddev
);
5775 blk_start_plug(&plug
);
5777 spin_lock_irq(&conf
->device_lock
);
5780 int batch_size
, released
;
5782 released
= release_stripe_list(conf
, conf
->temp_inactive_list
);
5784 clear_bit(R5_DID_ALLOC
, &conf
->cache_state
);
5787 !list_empty(&conf
->bitmap_list
)) {
5788 /* Now is a good time to flush some bitmap updates */
5790 spin_unlock_irq(&conf
->device_lock
);
5791 bitmap_unplug(mddev
->bitmap
);
5792 spin_lock_irq(&conf
->device_lock
);
5793 conf
->seq_write
= conf
->seq_flush
;
5794 activate_bit_delay(conf
, conf
->temp_inactive_list
);
5796 raid5_activate_delayed(conf
);
5798 while ((bio
= remove_bio_from_retry(conf
))) {
5800 spin_unlock_irq(&conf
->device_lock
);
5801 ok
= retry_aligned_read(conf
, bio
);
5802 spin_lock_irq(&conf
->device_lock
);
5808 batch_size
= handle_active_stripes(conf
, ANY_GROUP
, NULL
,
5809 conf
->temp_inactive_list
);
5810 if (!batch_size
&& !released
)
5812 handled
+= batch_size
;
5814 if (mddev
->flags
& ~(1<<MD_CHANGE_PENDING
)) {
5815 spin_unlock_irq(&conf
->device_lock
);
5816 md_check_recovery(mddev
);
5817 spin_lock_irq(&conf
->device_lock
);
5820 pr_debug("%d stripes handled\n", handled
);
5822 spin_unlock_irq(&conf
->device_lock
);
5823 if (test_and_clear_bit(R5_ALLOC_MORE
, &conf
->cache_state
)) {
5824 grow_one_stripe(conf
, __GFP_NOWARN
);
5825 /* Set flag even if allocation failed. This helps
5826 * slow down allocation requests when mem is short
5828 set_bit(R5_DID_ALLOC
, &conf
->cache_state
);
5831 async_tx_issue_pending_all();
5832 blk_finish_plug(&plug
);
5834 pr_debug("--- raid5d inactive\n");
5838 raid5_show_stripe_cache_size(struct mddev
*mddev
, char *page
)
5840 struct r5conf
*conf
;
5842 spin_lock(&mddev
->lock
);
5843 conf
= mddev
->private;
5845 ret
= sprintf(page
, "%d\n", conf
->min_nr_stripes
);
5846 spin_unlock(&mddev
->lock
);
5851 raid5_set_cache_size(struct mddev
*mddev
, int size
)
5853 struct r5conf
*conf
= mddev
->private;
5856 if (size
<= 16 || size
> 32768)
5859 conf
->min_nr_stripes
= size
;
5860 while (size
< conf
->max_nr_stripes
&&
5861 drop_one_stripe(conf
))
5865 err
= md_allow_write(mddev
);
5869 while (size
> conf
->max_nr_stripes
)
5870 if (!grow_one_stripe(conf
, GFP_KERNEL
))
5875 EXPORT_SYMBOL(raid5_set_cache_size
);
5878 raid5_store_stripe_cache_size(struct mddev
*mddev
, const char *page
, size_t len
)
5880 struct r5conf
*conf
;
5884 if (len
>= PAGE_SIZE
)
5886 if (kstrtoul(page
, 10, &new))
5888 err
= mddev_lock(mddev
);
5891 conf
= mddev
->private;
5895 err
= raid5_set_cache_size(mddev
, new);
5896 mddev_unlock(mddev
);
5901 static struct md_sysfs_entry
5902 raid5_stripecache_size
= __ATTR(stripe_cache_size
, S_IRUGO
| S_IWUSR
,
5903 raid5_show_stripe_cache_size
,
5904 raid5_store_stripe_cache_size
);
5907 raid5_show_rmw_level(struct mddev
*mddev
, char *page
)
5909 struct r5conf
*conf
= mddev
->private;
5911 return sprintf(page
, "%d\n", conf
->rmw_level
);
5917 raid5_store_rmw_level(struct mddev
*mddev
, const char *page
, size_t len
)
5919 struct r5conf
*conf
= mddev
->private;
5925 if (len
>= PAGE_SIZE
)
5928 if (kstrtoul(page
, 10, &new))
5931 if (new != PARITY_DISABLE_RMW
&& !raid6_call
.xor_syndrome
)
5934 if (new != PARITY_DISABLE_RMW
&&
5935 new != PARITY_ENABLE_RMW
&&
5936 new != PARITY_PREFER_RMW
)
5939 conf
->rmw_level
= new;
5943 static struct md_sysfs_entry
5944 raid5_rmw_level
= __ATTR(rmw_level
, S_IRUGO
| S_IWUSR
,
5945 raid5_show_rmw_level
,
5946 raid5_store_rmw_level
);
5950 raid5_show_preread_threshold(struct mddev
*mddev
, char *page
)
5952 struct r5conf
*conf
;
5954 spin_lock(&mddev
->lock
);
5955 conf
= mddev
->private;
5957 ret
= sprintf(page
, "%d\n", conf
->bypass_threshold
);
5958 spin_unlock(&mddev
->lock
);
5963 raid5_store_preread_threshold(struct mddev
*mddev
, const char *page
, size_t len
)
5965 struct r5conf
*conf
;
5969 if (len
>= PAGE_SIZE
)
5971 if (kstrtoul(page
, 10, &new))
5974 err
= mddev_lock(mddev
);
5977 conf
= mddev
->private;
5980 else if (new > conf
->min_nr_stripes
)
5983 conf
->bypass_threshold
= new;
5984 mddev_unlock(mddev
);
5988 static struct md_sysfs_entry
5989 raid5_preread_bypass_threshold
= __ATTR(preread_bypass_threshold
,
5991 raid5_show_preread_threshold
,
5992 raid5_store_preread_threshold
);
5995 raid5_show_skip_copy(struct mddev
*mddev
, char *page
)
5997 struct r5conf
*conf
;
5999 spin_lock(&mddev
->lock
);
6000 conf
= mddev
->private;
6002 ret
= sprintf(page
, "%d\n", conf
->skip_copy
);
6003 spin_unlock(&mddev
->lock
);
6008 raid5_store_skip_copy(struct mddev
*mddev
, const char *page
, size_t len
)
6010 struct r5conf
*conf
;
6014 if (len
>= PAGE_SIZE
)
6016 if (kstrtoul(page
, 10, &new))
6020 err
= mddev_lock(mddev
);
6023 conf
= mddev
->private;
6026 else if (new != conf
->skip_copy
) {
6027 mddev_suspend(mddev
);
6028 conf
->skip_copy
= new;
6030 mddev
->queue
->backing_dev_info
.capabilities
|=
6031 BDI_CAP_STABLE_WRITES
;
6033 mddev
->queue
->backing_dev_info
.capabilities
&=
6034 ~BDI_CAP_STABLE_WRITES
;
6035 mddev_resume(mddev
);
6037 mddev_unlock(mddev
);
6041 static struct md_sysfs_entry
6042 raid5_skip_copy
= __ATTR(skip_copy
, S_IRUGO
| S_IWUSR
,
6043 raid5_show_skip_copy
,
6044 raid5_store_skip_copy
);
6047 stripe_cache_active_show(struct mddev
*mddev
, char *page
)
6049 struct r5conf
*conf
= mddev
->private;
6051 return sprintf(page
, "%d\n", atomic_read(&conf
->active_stripes
));
6056 static struct md_sysfs_entry
6057 raid5_stripecache_active
= __ATTR_RO(stripe_cache_active
);
6060 raid5_show_group_thread_cnt(struct mddev
*mddev
, char *page
)
6062 struct r5conf
*conf
;
6064 spin_lock(&mddev
->lock
);
6065 conf
= mddev
->private;
6067 ret
= sprintf(page
, "%d\n", conf
->worker_cnt_per_group
);
6068 spin_unlock(&mddev
->lock
);
6072 static int alloc_thread_groups(struct r5conf
*conf
, int cnt
,
6074 int *worker_cnt_per_group
,
6075 struct r5worker_group
**worker_groups
);
6077 raid5_store_group_thread_cnt(struct mddev
*mddev
, const char *page
, size_t len
)
6079 struct r5conf
*conf
;
6082 struct r5worker_group
*new_groups
, *old_groups
;
6083 int group_cnt
, worker_cnt_per_group
;
6085 if (len
>= PAGE_SIZE
)
6087 if (kstrtoul(page
, 10, &new))
6090 err
= mddev_lock(mddev
);
6093 conf
= mddev
->private;
6096 else if (new != conf
->worker_cnt_per_group
) {
6097 mddev_suspend(mddev
);
6099 old_groups
= conf
->worker_groups
;
6101 flush_workqueue(raid5_wq
);
6103 err
= alloc_thread_groups(conf
, new,
6104 &group_cnt
, &worker_cnt_per_group
,
6107 spin_lock_irq(&conf
->device_lock
);
6108 conf
->group_cnt
= group_cnt
;
6109 conf
->worker_cnt_per_group
= worker_cnt_per_group
;
6110 conf
->worker_groups
= new_groups
;
6111 spin_unlock_irq(&conf
->device_lock
);
6114 kfree(old_groups
[0].workers
);
6117 mddev_resume(mddev
);
6119 mddev_unlock(mddev
);
6124 static struct md_sysfs_entry
6125 raid5_group_thread_cnt
= __ATTR(group_thread_cnt
, S_IRUGO
| S_IWUSR
,
6126 raid5_show_group_thread_cnt
,
6127 raid5_store_group_thread_cnt
);
6129 static struct attribute
*raid5_attrs
[] = {
6130 &raid5_stripecache_size
.attr
,
6131 &raid5_stripecache_active
.attr
,
6132 &raid5_preread_bypass_threshold
.attr
,
6133 &raid5_group_thread_cnt
.attr
,
6134 &raid5_skip_copy
.attr
,
6135 &raid5_rmw_level
.attr
,
6138 static struct attribute_group raid5_attrs_group
= {
6140 .attrs
= raid5_attrs
,
6143 static int alloc_thread_groups(struct r5conf
*conf
, int cnt
,
6145 int *worker_cnt_per_group
,
6146 struct r5worker_group
**worker_groups
)
6150 struct r5worker
*workers
;
6152 *worker_cnt_per_group
= cnt
;
6155 *worker_groups
= NULL
;
6158 *group_cnt
= num_possible_nodes();
6159 size
= sizeof(struct r5worker
) * cnt
;
6160 workers
= kzalloc(size
* *group_cnt
, GFP_NOIO
);
6161 *worker_groups
= kzalloc(sizeof(struct r5worker_group
) *
6162 *group_cnt
, GFP_NOIO
);
6163 if (!*worker_groups
|| !workers
) {
6165 kfree(*worker_groups
);
6169 for (i
= 0; i
< *group_cnt
; i
++) {
6170 struct r5worker_group
*group
;
6172 group
= &(*worker_groups
)[i
];
6173 INIT_LIST_HEAD(&group
->handle_list
);
6175 group
->workers
= workers
+ i
* cnt
;
6177 for (j
= 0; j
< cnt
; j
++) {
6178 struct r5worker
*worker
= group
->workers
+ j
;
6179 worker
->group
= group
;
6180 INIT_WORK(&worker
->work
, raid5_do_work
);
6182 for (k
= 0; k
< NR_STRIPE_HASH_LOCKS
; k
++)
6183 INIT_LIST_HEAD(worker
->temp_inactive_list
+ k
);
6190 static void free_thread_groups(struct r5conf
*conf
)
6192 if (conf
->worker_groups
)
6193 kfree(conf
->worker_groups
[0].workers
);
6194 kfree(conf
->worker_groups
);
6195 conf
->worker_groups
= NULL
;
6199 raid5_size(struct mddev
*mddev
, sector_t sectors
, int raid_disks
)
6201 struct r5conf
*conf
= mddev
->private;
6204 sectors
= mddev
->dev_sectors
;
6206 /* size is defined by the smallest of previous and new size */
6207 raid_disks
= min(conf
->raid_disks
, conf
->previous_raid_disks
);
6209 sectors
&= ~((sector_t
)mddev
->chunk_sectors
- 1);
6210 sectors
&= ~((sector_t
)mddev
->new_chunk_sectors
- 1);
6211 return sectors
* (raid_disks
- conf
->max_degraded
);
6214 static void free_scratch_buffer(struct r5conf
*conf
, struct raid5_percpu
*percpu
)
6216 safe_put_page(percpu
->spare_page
);
6217 if (percpu
->scribble
)
6218 flex_array_free(percpu
->scribble
);
6219 percpu
->spare_page
= NULL
;
6220 percpu
->scribble
= NULL
;
6223 static int alloc_scratch_buffer(struct r5conf
*conf
, struct raid5_percpu
*percpu
)
6225 if (conf
->level
== 6 && !percpu
->spare_page
)
6226 percpu
->spare_page
= alloc_page(GFP_KERNEL
);
6227 if (!percpu
->scribble
)
6228 percpu
->scribble
= scribble_alloc(max(conf
->raid_disks
,
6229 conf
->previous_raid_disks
),
6230 max(conf
->chunk_sectors
,
6231 conf
->prev_chunk_sectors
)
6235 if (!percpu
->scribble
|| (conf
->level
== 6 && !percpu
->spare_page
)) {
6236 free_scratch_buffer(conf
, percpu
);
6243 static void raid5_free_percpu(struct r5conf
*conf
)
6250 #ifdef CONFIG_HOTPLUG_CPU
6251 unregister_cpu_notifier(&conf
->cpu_notify
);
6255 for_each_possible_cpu(cpu
)
6256 free_scratch_buffer(conf
, per_cpu_ptr(conf
->percpu
, cpu
));
6259 free_percpu(conf
->percpu
);
6262 static void free_conf(struct r5conf
*conf
)
6264 if (conf
->shrinker
.seeks
)
6265 unregister_shrinker(&conf
->shrinker
);
6266 free_thread_groups(conf
);
6267 shrink_stripes(conf
);
6268 raid5_free_percpu(conf
);
6270 kfree(conf
->stripe_hashtbl
);
6274 #ifdef CONFIG_HOTPLUG_CPU
6275 static int raid456_cpu_notify(struct notifier_block
*nfb
, unsigned long action
,
6278 struct r5conf
*conf
= container_of(nfb
, struct r5conf
, cpu_notify
);
6279 long cpu
= (long)hcpu
;
6280 struct raid5_percpu
*percpu
= per_cpu_ptr(conf
->percpu
, cpu
);
6283 case CPU_UP_PREPARE
:
6284 case CPU_UP_PREPARE_FROZEN
:
6285 if (alloc_scratch_buffer(conf
, percpu
)) {
6286 pr_err("%s: failed memory allocation for cpu%ld\n",
6288 return notifier_from_errno(-ENOMEM
);
6292 case CPU_DEAD_FROZEN
:
6293 free_scratch_buffer(conf
, per_cpu_ptr(conf
->percpu
, cpu
));
6302 static int raid5_alloc_percpu(struct r5conf
*conf
)
6307 conf
->percpu
= alloc_percpu(struct raid5_percpu
);
6311 #ifdef CONFIG_HOTPLUG_CPU
6312 conf
->cpu_notify
.notifier_call
= raid456_cpu_notify
;
6313 conf
->cpu_notify
.priority
= 0;
6314 err
= register_cpu_notifier(&conf
->cpu_notify
);
6320 for_each_present_cpu(cpu
) {
6321 err
= alloc_scratch_buffer(conf
, per_cpu_ptr(conf
->percpu
, cpu
));
6323 pr_err("%s: failed memory allocation for cpu%ld\n",
6333 static unsigned long raid5_cache_scan(struct shrinker
*shrink
,
6334 struct shrink_control
*sc
)
6336 struct r5conf
*conf
= container_of(shrink
, struct r5conf
, shrinker
);
6338 while (ret
< sc
->nr_to_scan
) {
6339 if (drop_one_stripe(conf
) == 0)
6346 static unsigned long raid5_cache_count(struct shrinker
*shrink
,
6347 struct shrink_control
*sc
)
6349 struct r5conf
*conf
= container_of(shrink
, struct r5conf
, shrinker
);
6351 if (conf
->max_nr_stripes
< conf
->min_nr_stripes
)
6352 /* unlikely, but not impossible */
6354 return conf
->max_nr_stripes
- conf
->min_nr_stripes
;
6357 static struct r5conf
*setup_conf(struct mddev
*mddev
)
6359 struct r5conf
*conf
;
6360 int raid_disk
, memory
, max_disks
;
6361 struct md_rdev
*rdev
;
6362 struct disk_info
*disk
;
6365 int group_cnt
, worker_cnt_per_group
;
6366 struct r5worker_group
*new_group
;
6368 if (mddev
->new_level
!= 5
6369 && mddev
->new_level
!= 4
6370 && mddev
->new_level
!= 6) {
6371 printk(KERN_ERR
"md/raid:%s: raid level not set to 4/5/6 (%d)\n",
6372 mdname(mddev
), mddev
->new_level
);
6373 return ERR_PTR(-EIO
);
6375 if ((mddev
->new_level
== 5
6376 && !algorithm_valid_raid5(mddev
->new_layout
)) ||
6377 (mddev
->new_level
== 6
6378 && !algorithm_valid_raid6(mddev
->new_layout
))) {
6379 printk(KERN_ERR
"md/raid:%s: layout %d not supported\n",
6380 mdname(mddev
), mddev
->new_layout
);
6381 return ERR_PTR(-EIO
);
6383 if (mddev
->new_level
== 6 && mddev
->raid_disks
< 4) {
6384 printk(KERN_ERR
"md/raid:%s: not enough configured devices (%d, minimum 4)\n",
6385 mdname(mddev
), mddev
->raid_disks
);
6386 return ERR_PTR(-EINVAL
);
6389 if (!mddev
->new_chunk_sectors
||
6390 (mddev
->new_chunk_sectors
<< 9) % PAGE_SIZE
||
6391 !is_power_of_2(mddev
->new_chunk_sectors
)) {
6392 printk(KERN_ERR
"md/raid:%s: invalid chunk size %d\n",
6393 mdname(mddev
), mddev
->new_chunk_sectors
<< 9);
6394 return ERR_PTR(-EINVAL
);
6397 conf
= kzalloc(sizeof(struct r5conf
), GFP_KERNEL
);
6400 /* Don't enable multi-threading by default*/
6401 if (!alloc_thread_groups(conf
, 0, &group_cnt
, &worker_cnt_per_group
,
6403 conf
->group_cnt
= group_cnt
;
6404 conf
->worker_cnt_per_group
= worker_cnt_per_group
;
6405 conf
->worker_groups
= new_group
;
6408 spin_lock_init(&conf
->device_lock
);
6409 seqcount_init(&conf
->gen_lock
);
6410 init_waitqueue_head(&conf
->wait_for_stripe
);
6411 init_waitqueue_head(&conf
->wait_for_overlap
);
6412 INIT_LIST_HEAD(&conf
->handle_list
);
6413 INIT_LIST_HEAD(&conf
->hold_list
);
6414 INIT_LIST_HEAD(&conf
->delayed_list
);
6415 INIT_LIST_HEAD(&conf
->bitmap_list
);
6416 init_llist_head(&conf
->released_stripes
);
6417 atomic_set(&conf
->active_stripes
, 0);
6418 atomic_set(&conf
->preread_active_stripes
, 0);
6419 atomic_set(&conf
->active_aligned_reads
, 0);
6420 conf
->bypass_threshold
= BYPASS_THRESHOLD
;
6421 conf
->recovery_disabled
= mddev
->recovery_disabled
- 1;
6423 conf
->raid_disks
= mddev
->raid_disks
;
6424 if (mddev
->reshape_position
== MaxSector
)
6425 conf
->previous_raid_disks
= mddev
->raid_disks
;
6427 conf
->previous_raid_disks
= mddev
->raid_disks
- mddev
->delta_disks
;
6428 max_disks
= max(conf
->raid_disks
, conf
->previous_raid_disks
);
6430 conf
->disks
= kzalloc(max_disks
* sizeof(struct disk_info
),
6435 conf
->mddev
= mddev
;
6437 if ((conf
->stripe_hashtbl
= kzalloc(PAGE_SIZE
, GFP_KERNEL
)) == NULL
)
6440 /* We init hash_locks[0] separately to that it can be used
6441 * as the reference lock in the spin_lock_nest_lock() call
6442 * in lock_all_device_hash_locks_irq in order to convince
6443 * lockdep that we know what we are doing.
6445 spin_lock_init(conf
->hash_locks
);
6446 for (i
= 1; i
< NR_STRIPE_HASH_LOCKS
; i
++)
6447 spin_lock_init(conf
->hash_locks
+ i
);
6449 for (i
= 0; i
< NR_STRIPE_HASH_LOCKS
; i
++)
6450 INIT_LIST_HEAD(conf
->inactive_list
+ i
);
6452 for (i
= 0; i
< NR_STRIPE_HASH_LOCKS
; i
++)
6453 INIT_LIST_HEAD(conf
->temp_inactive_list
+ i
);
6455 conf
->level
= mddev
->new_level
;
6456 conf
->chunk_sectors
= mddev
->new_chunk_sectors
;
6457 if (raid5_alloc_percpu(conf
) != 0)
6460 pr_debug("raid456: run(%s) called.\n", mdname(mddev
));
6462 rdev_for_each(rdev
, mddev
) {
6463 raid_disk
= rdev
->raid_disk
;
6464 if (raid_disk
>= max_disks
6467 disk
= conf
->disks
+ raid_disk
;
6469 if (test_bit(Replacement
, &rdev
->flags
)) {
6470 if (disk
->replacement
)
6472 disk
->replacement
= rdev
;
6479 if (test_bit(In_sync
, &rdev
->flags
)) {
6480 char b
[BDEVNAME_SIZE
];
6481 printk(KERN_INFO
"md/raid:%s: device %s operational as raid"
6483 mdname(mddev
), bdevname(rdev
->bdev
, b
), raid_disk
);
6484 } else if (rdev
->saved_raid_disk
!= raid_disk
)
6485 /* Cannot rely on bitmap to complete recovery */
6489 conf
->level
= mddev
->new_level
;
6490 if (conf
->level
== 6) {
6491 conf
->max_degraded
= 2;
6492 if (raid6_call
.xor_syndrome
)
6493 conf
->rmw_level
= PARITY_ENABLE_RMW
;
6495 conf
->rmw_level
= PARITY_DISABLE_RMW
;
6497 conf
->max_degraded
= 1;
6498 conf
->rmw_level
= PARITY_ENABLE_RMW
;
6500 conf
->algorithm
= mddev
->new_layout
;
6501 conf
->reshape_progress
= mddev
->reshape_position
;
6502 if (conf
->reshape_progress
!= MaxSector
) {
6503 conf
->prev_chunk_sectors
= mddev
->chunk_sectors
;
6504 conf
->prev_algo
= mddev
->layout
;
6507 conf
->min_nr_stripes
= NR_STRIPES
;
6508 memory
= conf
->min_nr_stripes
* (sizeof(struct stripe_head
) +
6509 max_disks
* ((sizeof(struct bio
) + PAGE_SIZE
))) / 1024;
6510 atomic_set(&conf
->empty_inactive_list_nr
, NR_STRIPE_HASH_LOCKS
);
6511 if (grow_stripes(conf
, conf
->min_nr_stripes
)) {
6513 "md/raid:%s: couldn't allocate %dkB for buffers\n",
6514 mdname(mddev
), memory
);
6517 printk(KERN_INFO
"md/raid:%s: allocated %dkB\n",
6518 mdname(mddev
), memory
);
6520 * Losing a stripe head costs more than the time to refill it,
6521 * it reduces the queue depth and so can hurt throughput.
6522 * So set it rather large, scaled by number of devices.
6524 conf
->shrinker
.seeks
= DEFAULT_SEEKS
* conf
->raid_disks
* 4;
6525 conf
->shrinker
.scan_objects
= raid5_cache_scan
;
6526 conf
->shrinker
.count_objects
= raid5_cache_count
;
6527 conf
->shrinker
.batch
= 128;
6528 conf
->shrinker
.flags
= 0;
6529 register_shrinker(&conf
->shrinker
);
6531 sprintf(pers_name
, "raid%d", mddev
->new_level
);
6532 conf
->thread
= md_register_thread(raid5d
, mddev
, pers_name
);
6533 if (!conf
->thread
) {
6535 "md/raid:%s: couldn't allocate thread.\n",
6545 return ERR_PTR(-EIO
);
6547 return ERR_PTR(-ENOMEM
);
6550 static int only_parity(int raid_disk
, int algo
, int raid_disks
, int max_degraded
)
6553 case ALGORITHM_PARITY_0
:
6554 if (raid_disk
< max_degraded
)
6557 case ALGORITHM_PARITY_N
:
6558 if (raid_disk
>= raid_disks
- max_degraded
)
6561 case ALGORITHM_PARITY_0_6
:
6562 if (raid_disk
== 0 ||
6563 raid_disk
== raid_disks
- 1)
6566 case ALGORITHM_LEFT_ASYMMETRIC_6
:
6567 case ALGORITHM_RIGHT_ASYMMETRIC_6
:
6568 case ALGORITHM_LEFT_SYMMETRIC_6
:
6569 case ALGORITHM_RIGHT_SYMMETRIC_6
:
6570 if (raid_disk
== raid_disks
- 1)
6576 static int run(struct mddev
*mddev
)
6578 struct r5conf
*conf
;
6579 int working_disks
= 0;
6580 int dirty_parity_disks
= 0;
6581 struct md_rdev
*rdev
;
6582 sector_t reshape_offset
= 0;
6584 long long min_offset_diff
= 0;
6587 if (mddev
->recovery_cp
!= MaxSector
)
6588 printk(KERN_NOTICE
"md/raid:%s: not clean"
6589 " -- starting background reconstruction\n",
6592 rdev_for_each(rdev
, mddev
) {
6594 if (rdev
->raid_disk
< 0)
6596 diff
= (rdev
->new_data_offset
- rdev
->data_offset
);
6598 min_offset_diff
= diff
;
6600 } else if (mddev
->reshape_backwards
&&
6601 diff
< min_offset_diff
)
6602 min_offset_diff
= diff
;
6603 else if (!mddev
->reshape_backwards
&&
6604 diff
> min_offset_diff
)
6605 min_offset_diff
= diff
;
6608 if (mddev
->reshape_position
!= MaxSector
) {
6609 /* Check that we can continue the reshape.
6610 * Difficulties arise if the stripe we would write to
6611 * next is at or after the stripe we would read from next.
6612 * For a reshape that changes the number of devices, this
6613 * is only possible for a very short time, and mdadm makes
6614 * sure that time appears to have past before assembling
6615 * the array. So we fail if that time hasn't passed.
6616 * For a reshape that keeps the number of devices the same
6617 * mdadm must be monitoring the reshape can keeping the
6618 * critical areas read-only and backed up. It will start
6619 * the array in read-only mode, so we check for that.
6621 sector_t here_new
, here_old
;
6623 int max_degraded
= (mddev
->level
== 6 ? 2 : 1);
6625 if (mddev
->new_level
!= mddev
->level
) {
6626 printk(KERN_ERR
"md/raid:%s: unsupported reshape "
6627 "required - aborting.\n",
6631 old_disks
= mddev
->raid_disks
- mddev
->delta_disks
;
6632 /* reshape_position must be on a new-stripe boundary, and one
6633 * further up in new geometry must map after here in old
6636 here_new
= mddev
->reshape_position
;
6637 if (sector_div(here_new
, mddev
->new_chunk_sectors
*
6638 (mddev
->raid_disks
- max_degraded
))) {
6639 printk(KERN_ERR
"md/raid:%s: reshape_position not "
6640 "on a stripe boundary\n", mdname(mddev
));
6643 reshape_offset
= here_new
* mddev
->new_chunk_sectors
;
6644 /* here_new is the stripe we will write to */
6645 here_old
= mddev
->reshape_position
;
6646 sector_div(here_old
, mddev
->chunk_sectors
*
6647 (old_disks
-max_degraded
));
6648 /* here_old is the first stripe that we might need to read
6650 if (mddev
->delta_disks
== 0) {
6651 if ((here_new
* mddev
->new_chunk_sectors
!=
6652 here_old
* mddev
->chunk_sectors
)) {
6653 printk(KERN_ERR
"md/raid:%s: reshape position is"
6654 " confused - aborting\n", mdname(mddev
));
6657 /* We cannot be sure it is safe to start an in-place
6658 * reshape. It is only safe if user-space is monitoring
6659 * and taking constant backups.
6660 * mdadm always starts a situation like this in
6661 * readonly mode so it can take control before
6662 * allowing any writes. So just check for that.
6664 if (abs(min_offset_diff
) >= mddev
->chunk_sectors
&&
6665 abs(min_offset_diff
) >= mddev
->new_chunk_sectors
)
6666 /* not really in-place - so OK */;
6667 else if (mddev
->ro
== 0) {
6668 printk(KERN_ERR
"md/raid:%s: in-place reshape "
6669 "must be started in read-only mode "
6674 } else if (mddev
->reshape_backwards
6675 ? (here_new
* mddev
->new_chunk_sectors
+ min_offset_diff
<=
6676 here_old
* mddev
->chunk_sectors
)
6677 : (here_new
* mddev
->new_chunk_sectors
>=
6678 here_old
* mddev
->chunk_sectors
+ (-min_offset_diff
))) {
6679 /* Reading from the same stripe as writing to - bad */
6680 printk(KERN_ERR
"md/raid:%s: reshape_position too early for "
6681 "auto-recovery - aborting.\n",
6685 printk(KERN_INFO
"md/raid:%s: reshape will continue\n",
6687 /* OK, we should be able to continue; */
6689 BUG_ON(mddev
->level
!= mddev
->new_level
);
6690 BUG_ON(mddev
->layout
!= mddev
->new_layout
);
6691 BUG_ON(mddev
->chunk_sectors
!= mddev
->new_chunk_sectors
);
6692 BUG_ON(mddev
->delta_disks
!= 0);
6695 if (mddev
->private == NULL
)
6696 conf
= setup_conf(mddev
);
6698 conf
= mddev
->private;
6701 return PTR_ERR(conf
);
6703 conf
->min_offset_diff
= min_offset_diff
;
6704 mddev
->thread
= conf
->thread
;
6705 conf
->thread
= NULL
;
6706 mddev
->private = conf
;
6708 for (i
= 0; i
< conf
->raid_disks
&& conf
->previous_raid_disks
;
6710 rdev
= conf
->disks
[i
].rdev
;
6711 if (!rdev
&& conf
->disks
[i
].replacement
) {
6712 /* The replacement is all we have yet */
6713 rdev
= conf
->disks
[i
].replacement
;
6714 conf
->disks
[i
].replacement
= NULL
;
6715 clear_bit(Replacement
, &rdev
->flags
);
6716 conf
->disks
[i
].rdev
= rdev
;
6720 if (conf
->disks
[i
].replacement
&&
6721 conf
->reshape_progress
!= MaxSector
) {
6722 /* replacements and reshape simply do not mix. */
6723 printk(KERN_ERR
"md: cannot handle concurrent "
6724 "replacement and reshape.\n");
6727 if (test_bit(In_sync
, &rdev
->flags
)) {
6731 /* This disc is not fully in-sync. However if it
6732 * just stored parity (beyond the recovery_offset),
6733 * when we don't need to be concerned about the
6734 * array being dirty.
6735 * When reshape goes 'backwards', we never have
6736 * partially completed devices, so we only need
6737 * to worry about reshape going forwards.
6739 /* Hack because v0.91 doesn't store recovery_offset properly. */
6740 if (mddev
->major_version
== 0 &&
6741 mddev
->minor_version
> 90)
6742 rdev
->recovery_offset
= reshape_offset
;
6744 if (rdev
->recovery_offset
< reshape_offset
) {
6745 /* We need to check old and new layout */
6746 if (!only_parity(rdev
->raid_disk
,
6749 conf
->max_degraded
))
6752 if (!only_parity(rdev
->raid_disk
,
6754 conf
->previous_raid_disks
,
6755 conf
->max_degraded
))
6757 dirty_parity_disks
++;
6761 * 0 for a fully functional array, 1 or 2 for a degraded array.
6763 mddev
->degraded
= calc_degraded(conf
);
6765 if (has_failed(conf
)) {
6766 printk(KERN_ERR
"md/raid:%s: not enough operational devices"
6767 " (%d/%d failed)\n",
6768 mdname(mddev
), mddev
->degraded
, conf
->raid_disks
);
6772 /* device size must be a multiple of chunk size */
6773 mddev
->dev_sectors
&= ~(mddev
->chunk_sectors
- 1);
6774 mddev
->resync_max_sectors
= mddev
->dev_sectors
;
6776 if (mddev
->degraded
> dirty_parity_disks
&&
6777 mddev
->recovery_cp
!= MaxSector
) {
6778 if (mddev
->ok_start_degraded
)
6780 "md/raid:%s: starting dirty degraded array"
6781 " - data corruption possible.\n",
6785 "md/raid:%s: cannot start dirty degraded array.\n",
6791 if (mddev
->degraded
== 0)
6792 printk(KERN_INFO
"md/raid:%s: raid level %d active with %d out of %d"
6793 " devices, algorithm %d\n", mdname(mddev
), conf
->level
,
6794 mddev
->raid_disks
-mddev
->degraded
, mddev
->raid_disks
,
6797 printk(KERN_ALERT
"md/raid:%s: raid level %d active with %d"
6798 " out of %d devices, algorithm %d\n",
6799 mdname(mddev
), conf
->level
,
6800 mddev
->raid_disks
- mddev
->degraded
,
6801 mddev
->raid_disks
, mddev
->new_layout
);
6803 print_raid5_conf(conf
);
6805 if (conf
->reshape_progress
!= MaxSector
) {
6806 conf
->reshape_safe
= conf
->reshape_progress
;
6807 atomic_set(&conf
->reshape_stripes
, 0);
6808 clear_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
);
6809 clear_bit(MD_RECOVERY_CHECK
, &mddev
->recovery
);
6810 set_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
);
6811 set_bit(MD_RECOVERY_RUNNING
, &mddev
->recovery
);
6812 mddev
->sync_thread
= md_register_thread(md_do_sync
, mddev
,
6816 /* Ok, everything is just fine now */
6817 if (mddev
->to_remove
== &raid5_attrs_group
)
6818 mddev
->to_remove
= NULL
;
6819 else if (mddev
->kobj
.sd
&&
6820 sysfs_create_group(&mddev
->kobj
, &raid5_attrs_group
))
6822 "raid5: failed to create sysfs attributes for %s\n",
6824 md_set_array_sectors(mddev
, raid5_size(mddev
, 0, 0));
6828 bool discard_supported
= true;
6829 /* read-ahead size must cover two whole stripes, which
6830 * is 2 * (datadisks) * chunksize where 'n' is the
6831 * number of raid devices
6833 int data_disks
= conf
->previous_raid_disks
- conf
->max_degraded
;
6834 int stripe
= data_disks
*
6835 ((mddev
->chunk_sectors
<< 9) / PAGE_SIZE
);
6836 if (mddev
->queue
->backing_dev_info
.ra_pages
< 2 * stripe
)
6837 mddev
->queue
->backing_dev_info
.ra_pages
= 2 * stripe
;
6839 chunk_size
= mddev
->chunk_sectors
<< 9;
6840 blk_queue_io_min(mddev
->queue
, chunk_size
);
6841 blk_queue_io_opt(mddev
->queue
, chunk_size
*
6842 (conf
->raid_disks
- conf
->max_degraded
));
6843 mddev
->queue
->limits
.raid_partial_stripes_expensive
= 1;
6845 * We can only discard a whole stripe. It doesn't make sense to
6846 * discard data disk but write parity disk
6848 stripe
= stripe
* PAGE_SIZE
;
6849 /* Round up to power of 2, as discard handling
6850 * currently assumes that */
6851 while ((stripe
-1) & stripe
)
6852 stripe
= (stripe
| (stripe
-1)) + 1;
6853 mddev
->queue
->limits
.discard_alignment
= stripe
;
6854 mddev
->queue
->limits
.discard_granularity
= stripe
;
6856 * unaligned part of discard request will be ignored, so can't
6857 * guarantee discard_zeroes_data
6859 mddev
->queue
->limits
.discard_zeroes_data
= 0;
6861 blk_queue_max_write_same_sectors(mddev
->queue
, 0);
6863 rdev_for_each(rdev
, mddev
) {
6864 disk_stack_limits(mddev
->gendisk
, rdev
->bdev
,
6865 rdev
->data_offset
<< 9);
6866 disk_stack_limits(mddev
->gendisk
, rdev
->bdev
,
6867 rdev
->new_data_offset
<< 9);
6869 * discard_zeroes_data is required, otherwise data
6870 * could be lost. Consider a scenario: discard a stripe
6871 * (the stripe could be inconsistent if
6872 * discard_zeroes_data is 0); write one disk of the
6873 * stripe (the stripe could be inconsistent again
6874 * depending on which disks are used to calculate
6875 * parity); the disk is broken; The stripe data of this
6878 if (!blk_queue_discard(bdev_get_queue(rdev
->bdev
)) ||
6879 !bdev_get_queue(rdev
->bdev
)->
6880 limits
.discard_zeroes_data
)
6881 discard_supported
= false;
6882 /* Unfortunately, discard_zeroes_data is not currently
6883 * a guarantee - just a hint. So we only allow DISCARD
6884 * if the sysadmin has confirmed that only safe devices
6885 * are in use by setting a module parameter.
6887 if (!devices_handle_discard_safely
) {
6888 if (discard_supported
) {
6889 pr_info("md/raid456: discard support disabled due to uncertainty.\n");
6890 pr_info("Set raid456.devices_handle_discard_safely=Y to override.\n");
6892 discard_supported
= false;
6896 if (discard_supported
&&
6897 mddev
->queue
->limits
.max_discard_sectors
>= stripe
&&
6898 mddev
->queue
->limits
.discard_granularity
>= stripe
)
6899 queue_flag_set_unlocked(QUEUE_FLAG_DISCARD
,
6902 queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD
,
6908 md_unregister_thread(&mddev
->thread
);
6909 print_raid5_conf(conf
);
6911 mddev
->private = NULL
;
6912 printk(KERN_ALERT
"md/raid:%s: failed to run raid set.\n", mdname(mddev
));
6916 static void raid5_free(struct mddev
*mddev
, void *priv
)
6918 struct r5conf
*conf
= priv
;
6921 mddev
->to_remove
= &raid5_attrs_group
;
6924 static void status(struct seq_file
*seq
, struct mddev
*mddev
)
6926 struct r5conf
*conf
= mddev
->private;
6929 seq_printf(seq
, " level %d, %dk chunk, algorithm %d", mddev
->level
,
6930 mddev
->chunk_sectors
/ 2, mddev
->layout
);
6931 seq_printf (seq
, " [%d/%d] [", conf
->raid_disks
, conf
->raid_disks
- mddev
->degraded
);
6932 for (i
= 0; i
< conf
->raid_disks
; i
++)
6933 seq_printf (seq
, "%s",
6934 conf
->disks
[i
].rdev
&&
6935 test_bit(In_sync
, &conf
->disks
[i
].rdev
->flags
) ? "U" : "_");
6936 seq_printf (seq
, "]");
6939 static void print_raid5_conf (struct r5conf
*conf
)
6942 struct disk_info
*tmp
;
6944 printk(KERN_DEBUG
"RAID conf printout:\n");
6946 printk("(conf==NULL)\n");
6949 printk(KERN_DEBUG
" --- level:%d rd:%d wd:%d\n", conf
->level
,
6951 conf
->raid_disks
- conf
->mddev
->degraded
);
6953 for (i
= 0; i
< conf
->raid_disks
; i
++) {
6954 char b
[BDEVNAME_SIZE
];
6955 tmp
= conf
->disks
+ i
;
6957 printk(KERN_DEBUG
" disk %d, o:%d, dev:%s\n",
6958 i
, !test_bit(Faulty
, &tmp
->rdev
->flags
),
6959 bdevname(tmp
->rdev
->bdev
, b
));
6963 static int raid5_spare_active(struct mddev
*mddev
)
6966 struct r5conf
*conf
= mddev
->private;
6967 struct disk_info
*tmp
;
6969 unsigned long flags
;
6971 for (i
= 0; i
< conf
->raid_disks
; i
++) {
6972 tmp
= conf
->disks
+ i
;
6973 if (tmp
->replacement
6974 && tmp
->replacement
->recovery_offset
== MaxSector
6975 && !test_bit(Faulty
, &tmp
->replacement
->flags
)
6976 && !test_and_set_bit(In_sync
, &tmp
->replacement
->flags
)) {
6977 /* Replacement has just become active. */
6979 || !test_and_clear_bit(In_sync
, &tmp
->rdev
->flags
))
6982 /* Replaced device not technically faulty,
6983 * but we need to be sure it gets removed
6984 * and never re-added.
6986 set_bit(Faulty
, &tmp
->rdev
->flags
);
6987 sysfs_notify_dirent_safe(
6988 tmp
->rdev
->sysfs_state
);
6990 sysfs_notify_dirent_safe(tmp
->replacement
->sysfs_state
);
6991 } else if (tmp
->rdev
6992 && tmp
->rdev
->recovery_offset
== MaxSector
6993 && !test_bit(Faulty
, &tmp
->rdev
->flags
)
6994 && !test_and_set_bit(In_sync
, &tmp
->rdev
->flags
)) {
6996 sysfs_notify_dirent_safe(tmp
->rdev
->sysfs_state
);
6999 spin_lock_irqsave(&conf
->device_lock
, flags
);
7000 mddev
->degraded
= calc_degraded(conf
);
7001 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
7002 print_raid5_conf(conf
);
7006 static int raid5_remove_disk(struct mddev
*mddev
, struct md_rdev
*rdev
)
7008 struct r5conf
*conf
= mddev
->private;
7010 int number
= rdev
->raid_disk
;
7011 struct md_rdev
**rdevp
;
7012 struct disk_info
*p
= conf
->disks
+ number
;
7014 print_raid5_conf(conf
);
7015 if (rdev
== p
->rdev
)
7017 else if (rdev
== p
->replacement
)
7018 rdevp
= &p
->replacement
;
7022 if (number
>= conf
->raid_disks
&&
7023 conf
->reshape_progress
== MaxSector
)
7024 clear_bit(In_sync
, &rdev
->flags
);
7026 if (test_bit(In_sync
, &rdev
->flags
) ||
7027 atomic_read(&rdev
->nr_pending
)) {
7031 /* Only remove non-faulty devices if recovery
7034 if (!test_bit(Faulty
, &rdev
->flags
) &&
7035 mddev
->recovery_disabled
!= conf
->recovery_disabled
&&
7036 !has_failed(conf
) &&
7037 (!p
->replacement
|| p
->replacement
== rdev
) &&
7038 number
< conf
->raid_disks
) {
7044 if (atomic_read(&rdev
->nr_pending
)) {
7045 /* lost the race, try later */
7048 } else if (p
->replacement
) {
7049 /* We must have just cleared 'rdev' */
7050 p
->rdev
= p
->replacement
;
7051 clear_bit(Replacement
, &p
->replacement
->flags
);
7052 smp_mb(); /* Make sure other CPUs may see both as identical
7053 * but will never see neither - if they are careful
7055 p
->replacement
= NULL
;
7056 clear_bit(WantReplacement
, &rdev
->flags
);
7058 /* We might have just removed the Replacement as faulty-
7059 * clear the bit just in case
7061 clear_bit(WantReplacement
, &rdev
->flags
);
7064 print_raid5_conf(conf
);
7068 static int raid5_add_disk(struct mddev
*mddev
, struct md_rdev
*rdev
)
7070 struct r5conf
*conf
= mddev
->private;
7073 struct disk_info
*p
;
7075 int last
= conf
->raid_disks
- 1;
7077 if (mddev
->recovery_disabled
== conf
->recovery_disabled
)
7080 if (rdev
->saved_raid_disk
< 0 && has_failed(conf
))
7081 /* no point adding a device */
7084 if (rdev
->raid_disk
>= 0)
7085 first
= last
= rdev
->raid_disk
;
7088 * find the disk ... but prefer rdev->saved_raid_disk
7091 if (rdev
->saved_raid_disk
>= 0 &&
7092 rdev
->saved_raid_disk
>= first
&&
7093 conf
->disks
[rdev
->saved_raid_disk
].rdev
== NULL
)
7094 first
= rdev
->saved_raid_disk
;
7096 for (disk
= first
; disk
<= last
; disk
++) {
7097 p
= conf
->disks
+ disk
;
7098 if (p
->rdev
== NULL
) {
7099 clear_bit(In_sync
, &rdev
->flags
);
7100 rdev
->raid_disk
= disk
;
7102 if (rdev
->saved_raid_disk
!= disk
)
7104 rcu_assign_pointer(p
->rdev
, rdev
);
7108 for (disk
= first
; disk
<= last
; disk
++) {
7109 p
= conf
->disks
+ disk
;
7110 if (test_bit(WantReplacement
, &p
->rdev
->flags
) &&
7111 p
->replacement
== NULL
) {
7112 clear_bit(In_sync
, &rdev
->flags
);
7113 set_bit(Replacement
, &rdev
->flags
);
7114 rdev
->raid_disk
= disk
;
7117 rcu_assign_pointer(p
->replacement
, rdev
);
7122 print_raid5_conf(conf
);
7126 static int raid5_resize(struct mddev
*mddev
, sector_t sectors
)
7128 /* no resync is happening, and there is enough space
7129 * on all devices, so we can resize.
7130 * We need to make sure resync covers any new space.
7131 * If the array is shrinking we should possibly wait until
7132 * any io in the removed space completes, but it hardly seems
7136 sectors
&= ~((sector_t
)mddev
->chunk_sectors
- 1);
7137 newsize
= raid5_size(mddev
, sectors
, mddev
->raid_disks
);
7138 if (mddev
->external_size
&&
7139 mddev
->array_sectors
> newsize
)
7141 if (mddev
->bitmap
) {
7142 int ret
= bitmap_resize(mddev
->bitmap
, sectors
, 0, 0);
7146 md_set_array_sectors(mddev
, newsize
);
7147 set_capacity(mddev
->gendisk
, mddev
->array_sectors
);
7148 revalidate_disk(mddev
->gendisk
);
7149 if (sectors
> mddev
->dev_sectors
&&
7150 mddev
->recovery_cp
> mddev
->dev_sectors
) {
7151 mddev
->recovery_cp
= mddev
->dev_sectors
;
7152 set_bit(MD_RECOVERY_NEEDED
, &mddev
->recovery
);
7154 mddev
->dev_sectors
= sectors
;
7155 mddev
->resync_max_sectors
= sectors
;
7159 static int check_stripe_cache(struct mddev
*mddev
)
7161 /* Can only proceed if there are plenty of stripe_heads.
7162 * We need a minimum of one full stripe,, and for sensible progress
7163 * it is best to have about 4 times that.
7164 * If we require 4 times, then the default 256 4K stripe_heads will
7165 * allow for chunk sizes up to 256K, which is probably OK.
7166 * If the chunk size is greater, user-space should request more
7167 * stripe_heads first.
7169 struct r5conf
*conf
= mddev
->private;
7170 if (((mddev
->chunk_sectors
<< 9) / STRIPE_SIZE
) * 4
7171 > conf
->min_nr_stripes
||
7172 ((mddev
->new_chunk_sectors
<< 9) / STRIPE_SIZE
) * 4
7173 > conf
->min_nr_stripes
) {
7174 printk(KERN_WARNING
"md/raid:%s: reshape: not enough stripes. Needed %lu\n",
7176 ((max(mddev
->chunk_sectors
, mddev
->new_chunk_sectors
) << 9)
7183 static int check_reshape(struct mddev
*mddev
)
7185 struct r5conf
*conf
= mddev
->private;
7187 if (mddev
->delta_disks
== 0 &&
7188 mddev
->new_layout
== mddev
->layout
&&
7189 mddev
->new_chunk_sectors
== mddev
->chunk_sectors
)
7190 return 0; /* nothing to do */
7191 if (has_failed(conf
))
7193 if (mddev
->delta_disks
< 0 && mddev
->reshape_position
== MaxSector
) {
7194 /* We might be able to shrink, but the devices must
7195 * be made bigger first.
7196 * For raid6, 4 is the minimum size.
7197 * Otherwise 2 is the minimum
7200 if (mddev
->level
== 6)
7202 if (mddev
->raid_disks
+ mddev
->delta_disks
< min
)
7206 if (!check_stripe_cache(mddev
))
7209 if (mddev
->new_chunk_sectors
> mddev
->chunk_sectors
||
7210 mddev
->delta_disks
> 0)
7211 if (resize_chunks(conf
,
7212 conf
->previous_raid_disks
7213 + max(0, mddev
->delta_disks
),
7214 max(mddev
->new_chunk_sectors
,
7215 mddev
->chunk_sectors
)
7218 return resize_stripes(conf
, (conf
->previous_raid_disks
7219 + mddev
->delta_disks
));
7222 static int raid5_start_reshape(struct mddev
*mddev
)
7224 struct r5conf
*conf
= mddev
->private;
7225 struct md_rdev
*rdev
;
7227 unsigned long flags
;
7229 if (test_bit(MD_RECOVERY_RUNNING
, &mddev
->recovery
))
7232 if (!check_stripe_cache(mddev
))
7235 if (has_failed(conf
))
7238 rdev_for_each(rdev
, mddev
) {
7239 if (!test_bit(In_sync
, &rdev
->flags
)
7240 && !test_bit(Faulty
, &rdev
->flags
))
7244 if (spares
- mddev
->degraded
< mddev
->delta_disks
- conf
->max_degraded
)
7245 /* Not enough devices even to make a degraded array
7250 /* Refuse to reduce size of the array. Any reductions in
7251 * array size must be through explicit setting of array_size
7254 if (raid5_size(mddev
, 0, conf
->raid_disks
+ mddev
->delta_disks
)
7255 < mddev
->array_sectors
) {
7256 printk(KERN_ERR
"md/raid:%s: array size must be reduced "
7257 "before number of disks\n", mdname(mddev
));
7261 atomic_set(&conf
->reshape_stripes
, 0);
7262 spin_lock_irq(&conf
->device_lock
);
7263 write_seqcount_begin(&conf
->gen_lock
);
7264 conf
->previous_raid_disks
= conf
->raid_disks
;
7265 conf
->raid_disks
+= mddev
->delta_disks
;
7266 conf
->prev_chunk_sectors
= conf
->chunk_sectors
;
7267 conf
->chunk_sectors
= mddev
->new_chunk_sectors
;
7268 conf
->prev_algo
= conf
->algorithm
;
7269 conf
->algorithm
= mddev
->new_layout
;
7271 /* Code that selects data_offset needs to see the generation update
7272 * if reshape_progress has been set - so a memory barrier needed.
7275 if (mddev
->reshape_backwards
)
7276 conf
->reshape_progress
= raid5_size(mddev
, 0, 0);
7278 conf
->reshape_progress
= 0;
7279 conf
->reshape_safe
= conf
->reshape_progress
;
7280 write_seqcount_end(&conf
->gen_lock
);
7281 spin_unlock_irq(&conf
->device_lock
);
7283 /* Now make sure any requests that proceeded on the assumption
7284 * the reshape wasn't running - like Discard or Read - have
7287 mddev_suspend(mddev
);
7288 mddev_resume(mddev
);
7290 /* Add some new drives, as many as will fit.
7291 * We know there are enough to make the newly sized array work.
7292 * Don't add devices if we are reducing the number of
7293 * devices in the array. This is because it is not possible
7294 * to correctly record the "partially reconstructed" state of
7295 * such devices during the reshape and confusion could result.
7297 if (mddev
->delta_disks
>= 0) {
7298 rdev_for_each(rdev
, mddev
)
7299 if (rdev
->raid_disk
< 0 &&
7300 !test_bit(Faulty
, &rdev
->flags
)) {
7301 if (raid5_add_disk(mddev
, rdev
) == 0) {
7303 >= conf
->previous_raid_disks
)
7304 set_bit(In_sync
, &rdev
->flags
);
7306 rdev
->recovery_offset
= 0;
7308 if (sysfs_link_rdev(mddev
, rdev
))
7309 /* Failure here is OK */;
7311 } else if (rdev
->raid_disk
>= conf
->previous_raid_disks
7312 && !test_bit(Faulty
, &rdev
->flags
)) {
7313 /* This is a spare that was manually added */
7314 set_bit(In_sync
, &rdev
->flags
);
7317 /* When a reshape changes the number of devices,
7318 * ->degraded is measured against the larger of the
7319 * pre and post number of devices.
7321 spin_lock_irqsave(&conf
->device_lock
, flags
);
7322 mddev
->degraded
= calc_degraded(conf
);
7323 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
7325 mddev
->raid_disks
= conf
->raid_disks
;
7326 mddev
->reshape_position
= conf
->reshape_progress
;
7327 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
7329 clear_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
);
7330 clear_bit(MD_RECOVERY_CHECK
, &mddev
->recovery
);
7331 set_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
);
7332 set_bit(MD_RECOVERY_RUNNING
, &mddev
->recovery
);
7333 mddev
->sync_thread
= md_register_thread(md_do_sync
, mddev
,
7335 if (!mddev
->sync_thread
) {
7336 mddev
->recovery
= 0;
7337 spin_lock_irq(&conf
->device_lock
);
7338 write_seqcount_begin(&conf
->gen_lock
);
7339 mddev
->raid_disks
= conf
->raid_disks
= conf
->previous_raid_disks
;
7340 mddev
->new_chunk_sectors
=
7341 conf
->chunk_sectors
= conf
->prev_chunk_sectors
;
7342 mddev
->new_layout
= conf
->algorithm
= conf
->prev_algo
;
7343 rdev_for_each(rdev
, mddev
)
7344 rdev
->new_data_offset
= rdev
->data_offset
;
7346 conf
->generation
--;
7347 conf
->reshape_progress
= MaxSector
;
7348 mddev
->reshape_position
= MaxSector
;
7349 write_seqcount_end(&conf
->gen_lock
);
7350 spin_unlock_irq(&conf
->device_lock
);
7353 conf
->reshape_checkpoint
= jiffies
;
7354 md_wakeup_thread(mddev
->sync_thread
);
7355 md_new_event(mddev
);
7359 /* This is called from the reshape thread and should make any
7360 * changes needed in 'conf'
7362 static void end_reshape(struct r5conf
*conf
)
7365 if (!test_bit(MD_RECOVERY_INTR
, &conf
->mddev
->recovery
)) {
7366 struct md_rdev
*rdev
;
7368 spin_lock_irq(&conf
->device_lock
);
7369 conf
->previous_raid_disks
= conf
->raid_disks
;
7370 rdev_for_each(rdev
, conf
->mddev
)
7371 rdev
->data_offset
= rdev
->new_data_offset
;
7373 conf
->reshape_progress
= MaxSector
;
7374 spin_unlock_irq(&conf
->device_lock
);
7375 wake_up(&conf
->wait_for_overlap
);
7377 /* read-ahead size must cover two whole stripes, which is
7378 * 2 * (datadisks) * chunksize where 'n' is the number of raid devices
7380 if (conf
->mddev
->queue
) {
7381 int data_disks
= conf
->raid_disks
- conf
->max_degraded
;
7382 int stripe
= data_disks
* ((conf
->chunk_sectors
<< 9)
7384 if (conf
->mddev
->queue
->backing_dev_info
.ra_pages
< 2 * stripe
)
7385 conf
->mddev
->queue
->backing_dev_info
.ra_pages
= 2 * stripe
;
7390 /* This is called from the raid5d thread with mddev_lock held.
7391 * It makes config changes to the device.
7393 static void raid5_finish_reshape(struct mddev
*mddev
)
7395 struct r5conf
*conf
= mddev
->private;
7397 if (!test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
)) {
7399 if (mddev
->delta_disks
> 0) {
7400 md_set_array_sectors(mddev
, raid5_size(mddev
, 0, 0));
7401 set_capacity(mddev
->gendisk
, mddev
->array_sectors
);
7402 revalidate_disk(mddev
->gendisk
);
7405 spin_lock_irq(&conf
->device_lock
);
7406 mddev
->degraded
= calc_degraded(conf
);
7407 spin_unlock_irq(&conf
->device_lock
);
7408 for (d
= conf
->raid_disks
;
7409 d
< conf
->raid_disks
- mddev
->delta_disks
;
7411 struct md_rdev
*rdev
= conf
->disks
[d
].rdev
;
7413 clear_bit(In_sync
, &rdev
->flags
);
7414 rdev
= conf
->disks
[d
].replacement
;
7416 clear_bit(In_sync
, &rdev
->flags
);
7419 mddev
->layout
= conf
->algorithm
;
7420 mddev
->chunk_sectors
= conf
->chunk_sectors
;
7421 mddev
->reshape_position
= MaxSector
;
7422 mddev
->delta_disks
= 0;
7423 mddev
->reshape_backwards
= 0;
7427 static void raid5_quiesce(struct mddev
*mddev
, int state
)
7429 struct r5conf
*conf
= mddev
->private;
7432 case 2: /* resume for a suspend */
7433 wake_up(&conf
->wait_for_overlap
);
7436 case 1: /* stop all writes */
7437 lock_all_device_hash_locks_irq(conf
);
7438 /* '2' tells resync/reshape to pause so that all
7439 * active stripes can drain
7442 wait_event_cmd(conf
->wait_for_stripe
,
7443 atomic_read(&conf
->active_stripes
) == 0 &&
7444 atomic_read(&conf
->active_aligned_reads
) == 0,
7445 unlock_all_device_hash_locks_irq(conf
),
7446 lock_all_device_hash_locks_irq(conf
));
7448 unlock_all_device_hash_locks_irq(conf
);
7449 /* allow reshape to continue */
7450 wake_up(&conf
->wait_for_overlap
);
7453 case 0: /* re-enable writes */
7454 lock_all_device_hash_locks_irq(conf
);
7456 wake_up(&conf
->wait_for_stripe
);
7457 wake_up(&conf
->wait_for_overlap
);
7458 unlock_all_device_hash_locks_irq(conf
);
7463 static void *raid45_takeover_raid0(struct mddev
*mddev
, int level
)
7465 struct r0conf
*raid0_conf
= mddev
->private;
7468 /* for raid0 takeover only one zone is supported */
7469 if (raid0_conf
->nr_strip_zones
> 1) {
7470 printk(KERN_ERR
"md/raid:%s: cannot takeover raid0 with more than one zone.\n",
7472 return ERR_PTR(-EINVAL
);
7475 sectors
= raid0_conf
->strip_zone
[0].zone_end
;
7476 sector_div(sectors
, raid0_conf
->strip_zone
[0].nb_dev
);
7477 mddev
->dev_sectors
= sectors
;
7478 mddev
->new_level
= level
;
7479 mddev
->new_layout
= ALGORITHM_PARITY_N
;
7480 mddev
->new_chunk_sectors
= mddev
->chunk_sectors
;
7481 mddev
->raid_disks
+= 1;
7482 mddev
->delta_disks
= 1;
7483 /* make sure it will be not marked as dirty */
7484 mddev
->recovery_cp
= MaxSector
;
7486 return setup_conf(mddev
);
7489 static void *raid5_takeover_raid1(struct mddev
*mddev
)
7493 if (mddev
->raid_disks
!= 2 ||
7494 mddev
->degraded
> 1)
7495 return ERR_PTR(-EINVAL
);
7497 /* Should check if there are write-behind devices? */
7499 chunksect
= 64*2; /* 64K by default */
7501 /* The array must be an exact multiple of chunksize */
7502 while (chunksect
&& (mddev
->array_sectors
& (chunksect
-1)))
7505 if ((chunksect
<<9) < STRIPE_SIZE
)
7506 /* array size does not allow a suitable chunk size */
7507 return ERR_PTR(-EINVAL
);
7509 mddev
->new_level
= 5;
7510 mddev
->new_layout
= ALGORITHM_LEFT_SYMMETRIC
;
7511 mddev
->new_chunk_sectors
= chunksect
;
7513 return setup_conf(mddev
);
7516 static void *raid5_takeover_raid6(struct mddev
*mddev
)
7520 switch (mddev
->layout
) {
7521 case ALGORITHM_LEFT_ASYMMETRIC_6
:
7522 new_layout
= ALGORITHM_LEFT_ASYMMETRIC
;
7524 case ALGORITHM_RIGHT_ASYMMETRIC_6
:
7525 new_layout
= ALGORITHM_RIGHT_ASYMMETRIC
;
7527 case ALGORITHM_LEFT_SYMMETRIC_6
:
7528 new_layout
= ALGORITHM_LEFT_SYMMETRIC
;
7530 case ALGORITHM_RIGHT_SYMMETRIC_6
:
7531 new_layout
= ALGORITHM_RIGHT_SYMMETRIC
;
7533 case ALGORITHM_PARITY_0_6
:
7534 new_layout
= ALGORITHM_PARITY_0
;
7536 case ALGORITHM_PARITY_N
:
7537 new_layout
= ALGORITHM_PARITY_N
;
7540 return ERR_PTR(-EINVAL
);
7542 mddev
->new_level
= 5;
7543 mddev
->new_layout
= new_layout
;
7544 mddev
->delta_disks
= -1;
7545 mddev
->raid_disks
-= 1;
7546 return setup_conf(mddev
);
7549 static int raid5_check_reshape(struct mddev
*mddev
)
7551 /* For a 2-drive array, the layout and chunk size can be changed
7552 * immediately as not restriping is needed.
7553 * For larger arrays we record the new value - after validation
7554 * to be used by a reshape pass.
7556 struct r5conf
*conf
= mddev
->private;
7557 int new_chunk
= mddev
->new_chunk_sectors
;
7559 if (mddev
->new_layout
>= 0 && !algorithm_valid_raid5(mddev
->new_layout
))
7561 if (new_chunk
> 0) {
7562 if (!is_power_of_2(new_chunk
))
7564 if (new_chunk
< (PAGE_SIZE
>>9))
7566 if (mddev
->array_sectors
& (new_chunk
-1))
7567 /* not factor of array size */
7571 /* They look valid */
7573 if (mddev
->raid_disks
== 2) {
7574 /* can make the change immediately */
7575 if (mddev
->new_layout
>= 0) {
7576 conf
->algorithm
= mddev
->new_layout
;
7577 mddev
->layout
= mddev
->new_layout
;
7579 if (new_chunk
> 0) {
7580 conf
->chunk_sectors
= new_chunk
;
7581 mddev
->chunk_sectors
= new_chunk
;
7583 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
7584 md_wakeup_thread(mddev
->thread
);
7586 return check_reshape(mddev
);
7589 static int raid6_check_reshape(struct mddev
*mddev
)
7591 int new_chunk
= mddev
->new_chunk_sectors
;
7593 if (mddev
->new_layout
>= 0 && !algorithm_valid_raid6(mddev
->new_layout
))
7595 if (new_chunk
> 0) {
7596 if (!is_power_of_2(new_chunk
))
7598 if (new_chunk
< (PAGE_SIZE
>> 9))
7600 if (mddev
->array_sectors
& (new_chunk
-1))
7601 /* not factor of array size */
7605 /* They look valid */
7606 return check_reshape(mddev
);
7609 static void *raid5_takeover(struct mddev
*mddev
)
7611 /* raid5 can take over:
7612 * raid0 - if there is only one strip zone - make it a raid4 layout
7613 * raid1 - if there are two drives. We need to know the chunk size
7614 * raid4 - trivial - just use a raid4 layout.
7615 * raid6 - Providing it is a *_6 layout
7617 if (mddev
->level
== 0)
7618 return raid45_takeover_raid0(mddev
, 5);
7619 if (mddev
->level
== 1)
7620 return raid5_takeover_raid1(mddev
);
7621 if (mddev
->level
== 4) {
7622 mddev
->new_layout
= ALGORITHM_PARITY_N
;
7623 mddev
->new_level
= 5;
7624 return setup_conf(mddev
);
7626 if (mddev
->level
== 6)
7627 return raid5_takeover_raid6(mddev
);
7629 return ERR_PTR(-EINVAL
);
7632 static void *raid4_takeover(struct mddev
*mddev
)
7634 /* raid4 can take over:
7635 * raid0 - if there is only one strip zone
7636 * raid5 - if layout is right
7638 if (mddev
->level
== 0)
7639 return raid45_takeover_raid0(mddev
, 4);
7640 if (mddev
->level
== 5 &&
7641 mddev
->layout
== ALGORITHM_PARITY_N
) {
7642 mddev
->new_layout
= 0;
7643 mddev
->new_level
= 4;
7644 return setup_conf(mddev
);
7646 return ERR_PTR(-EINVAL
);
7649 static struct md_personality raid5_personality
;
7651 static void *raid6_takeover(struct mddev
*mddev
)
7653 /* Currently can only take over a raid5. We map the
7654 * personality to an equivalent raid6 personality
7655 * with the Q block at the end.
7659 if (mddev
->pers
!= &raid5_personality
)
7660 return ERR_PTR(-EINVAL
);
7661 if (mddev
->degraded
> 1)
7662 return ERR_PTR(-EINVAL
);
7663 if (mddev
->raid_disks
> 253)
7664 return ERR_PTR(-EINVAL
);
7665 if (mddev
->raid_disks
< 3)
7666 return ERR_PTR(-EINVAL
);
7668 switch (mddev
->layout
) {
7669 case ALGORITHM_LEFT_ASYMMETRIC
:
7670 new_layout
= ALGORITHM_LEFT_ASYMMETRIC_6
;
7672 case ALGORITHM_RIGHT_ASYMMETRIC
:
7673 new_layout
= ALGORITHM_RIGHT_ASYMMETRIC_6
;
7675 case ALGORITHM_LEFT_SYMMETRIC
:
7676 new_layout
= ALGORITHM_LEFT_SYMMETRIC_6
;
7678 case ALGORITHM_RIGHT_SYMMETRIC
:
7679 new_layout
= ALGORITHM_RIGHT_SYMMETRIC_6
;
7681 case ALGORITHM_PARITY_0
:
7682 new_layout
= ALGORITHM_PARITY_0_6
;
7684 case ALGORITHM_PARITY_N
:
7685 new_layout
= ALGORITHM_PARITY_N
;
7688 return ERR_PTR(-EINVAL
);
7690 mddev
->new_level
= 6;
7691 mddev
->new_layout
= new_layout
;
7692 mddev
->delta_disks
= 1;
7693 mddev
->raid_disks
+= 1;
7694 return setup_conf(mddev
);
7697 static struct md_personality raid6_personality
=
7701 .owner
= THIS_MODULE
,
7702 .make_request
= make_request
,
7706 .error_handler
= error
,
7707 .hot_add_disk
= raid5_add_disk
,
7708 .hot_remove_disk
= raid5_remove_disk
,
7709 .spare_active
= raid5_spare_active
,
7710 .sync_request
= sync_request
,
7711 .resize
= raid5_resize
,
7713 .check_reshape
= raid6_check_reshape
,
7714 .start_reshape
= raid5_start_reshape
,
7715 .finish_reshape
= raid5_finish_reshape
,
7716 .quiesce
= raid5_quiesce
,
7717 .takeover
= raid6_takeover
,
7718 .congested
= raid5_congested
,
7719 .mergeable_bvec
= raid5_mergeable_bvec
,
7721 static struct md_personality raid5_personality
=
7725 .owner
= THIS_MODULE
,
7726 .make_request
= make_request
,
7730 .error_handler
= error
,
7731 .hot_add_disk
= raid5_add_disk
,
7732 .hot_remove_disk
= raid5_remove_disk
,
7733 .spare_active
= raid5_spare_active
,
7734 .sync_request
= sync_request
,
7735 .resize
= raid5_resize
,
7737 .check_reshape
= raid5_check_reshape
,
7738 .start_reshape
= raid5_start_reshape
,
7739 .finish_reshape
= raid5_finish_reshape
,
7740 .quiesce
= raid5_quiesce
,
7741 .takeover
= raid5_takeover
,
7742 .congested
= raid5_congested
,
7743 .mergeable_bvec
= raid5_mergeable_bvec
,
7746 static struct md_personality raid4_personality
=
7750 .owner
= THIS_MODULE
,
7751 .make_request
= make_request
,
7755 .error_handler
= error
,
7756 .hot_add_disk
= raid5_add_disk
,
7757 .hot_remove_disk
= raid5_remove_disk
,
7758 .spare_active
= raid5_spare_active
,
7759 .sync_request
= sync_request
,
7760 .resize
= raid5_resize
,
7762 .check_reshape
= raid5_check_reshape
,
7763 .start_reshape
= raid5_start_reshape
,
7764 .finish_reshape
= raid5_finish_reshape
,
7765 .quiesce
= raid5_quiesce
,
7766 .takeover
= raid4_takeover
,
7767 .congested
= raid5_congested
,
7768 .mergeable_bvec
= raid5_mergeable_bvec
,
7771 static int __init
raid5_init(void)
7773 raid5_wq
= alloc_workqueue("raid5wq",
7774 WQ_UNBOUND
|WQ_MEM_RECLAIM
|WQ_CPU_INTENSIVE
|WQ_SYSFS
, 0);
7777 register_md_personality(&raid6_personality
);
7778 register_md_personality(&raid5_personality
);
7779 register_md_personality(&raid4_personality
);
7783 static void raid5_exit(void)
7785 unregister_md_personality(&raid6_personality
);
7786 unregister_md_personality(&raid5_personality
);
7787 unregister_md_personality(&raid4_personality
);
7788 destroy_workqueue(raid5_wq
);
7791 module_init(raid5_init
);
7792 module_exit(raid5_exit
);
7793 MODULE_LICENSE("GPL");
7794 MODULE_DESCRIPTION("RAID4/5/6 (striping with parity) personality for MD");
7795 MODULE_ALIAS("md-personality-4"); /* RAID5 */
7796 MODULE_ALIAS("md-raid5");
7797 MODULE_ALIAS("md-raid4");
7798 MODULE_ALIAS("md-level-5");
7799 MODULE_ALIAS("md-level-4");
7800 MODULE_ALIAS("md-personality-8"); /* RAID6 */
7801 MODULE_ALIAS("md-raid6");
7802 MODULE_ALIAS("md-level-6");
7804 /* This used to be two separate modules, they were: */
7805 MODULE_ALIAS("raid5");
7806 MODULE_ALIAS("raid6");