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 !test_bit(STRIPE_BITMAP_PENDING
, &sh
->state
) &&
753 is_full_stripe_write(sh
);
756 /* we only do back search */
757 static void stripe_add_to_batch_list(struct r5conf
*conf
, struct stripe_head
*sh
)
759 struct stripe_head
*head
;
760 sector_t head_sector
, tmp_sec
;
764 if (!stripe_can_batch(sh
))
766 /* Don't cross chunks, so stripe pd_idx/qd_idx is the same */
767 tmp_sec
= sh
->sector
;
768 if (!sector_div(tmp_sec
, conf
->chunk_sectors
))
770 head_sector
= sh
->sector
- STRIPE_SECTORS
;
772 hash
= stripe_hash_locks_hash(head_sector
);
773 spin_lock_irq(conf
->hash_locks
+ hash
);
774 head
= __find_stripe(conf
, head_sector
, conf
->generation
);
775 if (head
&& !atomic_inc_not_zero(&head
->count
)) {
776 spin_lock(&conf
->device_lock
);
777 if (!atomic_read(&head
->count
)) {
778 if (!test_bit(STRIPE_HANDLE
, &head
->state
))
779 atomic_inc(&conf
->active_stripes
);
780 BUG_ON(list_empty(&head
->lru
) &&
781 !test_bit(STRIPE_EXPANDING
, &head
->state
));
782 list_del_init(&head
->lru
);
784 head
->group
->stripes_cnt
--;
788 atomic_inc(&head
->count
);
789 spin_unlock(&conf
->device_lock
);
791 spin_unlock_irq(conf
->hash_locks
+ hash
);
795 if (!stripe_can_batch(head
))
798 lock_two_stripes(head
, sh
);
799 /* clear_batch_ready clear the flag */
800 if (!stripe_can_batch(head
) || !stripe_can_batch(sh
))
807 while (dd_idx
== sh
->pd_idx
|| dd_idx
== sh
->qd_idx
)
809 if (head
->dev
[dd_idx
].towrite
->bi_rw
!= sh
->dev
[dd_idx
].towrite
->bi_rw
)
812 if (head
->batch_head
) {
813 spin_lock(&head
->batch_head
->batch_lock
);
814 /* This batch list is already running */
815 if (!stripe_can_batch(head
)) {
816 spin_unlock(&head
->batch_head
->batch_lock
);
821 * at this point, head's BATCH_READY could be cleared, but we
822 * can still add the stripe to batch list
824 list_add(&sh
->batch_list
, &head
->batch_list
);
825 spin_unlock(&head
->batch_head
->batch_lock
);
827 sh
->batch_head
= head
->batch_head
;
829 head
->batch_head
= head
;
830 sh
->batch_head
= head
->batch_head
;
831 spin_lock(&head
->batch_lock
);
832 list_add_tail(&sh
->batch_list
, &head
->batch_list
);
833 spin_unlock(&head
->batch_lock
);
836 if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
837 if (atomic_dec_return(&conf
->preread_active_stripes
)
839 md_wakeup_thread(conf
->mddev
->thread
);
841 if (test_and_clear_bit(STRIPE_BIT_DELAY
, &sh
->state
)) {
842 int seq
= sh
->bm_seq
;
843 if (test_bit(STRIPE_BIT_DELAY
, &sh
->batch_head
->state
) &&
844 sh
->batch_head
->bm_seq
> seq
)
845 seq
= sh
->batch_head
->bm_seq
;
846 set_bit(STRIPE_BIT_DELAY
, &sh
->batch_head
->state
);
847 sh
->batch_head
->bm_seq
= seq
;
850 atomic_inc(&sh
->count
);
852 unlock_two_stripes(head
, sh
);
854 release_stripe(head
);
857 /* Determine if 'data_offset' or 'new_data_offset' should be used
858 * in this stripe_head.
860 static int use_new_offset(struct r5conf
*conf
, struct stripe_head
*sh
)
862 sector_t progress
= conf
->reshape_progress
;
863 /* Need a memory barrier to make sure we see the value
864 * of conf->generation, or ->data_offset that was set before
865 * reshape_progress was updated.
868 if (progress
== MaxSector
)
870 if (sh
->generation
== conf
->generation
- 1)
872 /* We are in a reshape, and this is a new-generation stripe,
873 * so use new_data_offset.
879 raid5_end_read_request(struct bio
*bi
, int error
);
881 raid5_end_write_request(struct bio
*bi
, int error
);
883 static void ops_run_io(struct stripe_head
*sh
, struct stripe_head_state
*s
)
885 struct r5conf
*conf
= sh
->raid_conf
;
886 int i
, disks
= sh
->disks
;
887 struct stripe_head
*head_sh
= sh
;
891 for (i
= disks
; i
--; ) {
893 int replace_only
= 0;
894 struct bio
*bi
, *rbi
;
895 struct md_rdev
*rdev
, *rrdev
= NULL
;
898 if (test_and_clear_bit(R5_Wantwrite
, &sh
->dev
[i
].flags
)) {
899 if (test_and_clear_bit(R5_WantFUA
, &sh
->dev
[i
].flags
))
903 if (test_bit(R5_Discard
, &sh
->dev
[i
].flags
))
905 } else if (test_and_clear_bit(R5_Wantread
, &sh
->dev
[i
].flags
))
907 else if (test_and_clear_bit(R5_WantReplace
,
908 &sh
->dev
[i
].flags
)) {
913 if (test_and_clear_bit(R5_SyncIO
, &sh
->dev
[i
].flags
))
917 bi
= &sh
->dev
[i
].req
;
918 rbi
= &sh
->dev
[i
].rreq
; /* For writing to replacement */
921 rrdev
= rcu_dereference(conf
->disks
[i
].replacement
);
922 smp_mb(); /* Ensure that if rrdev is NULL, rdev won't be */
923 rdev
= rcu_dereference(conf
->disks
[i
].rdev
);
932 /* We raced and saw duplicates */
935 if (test_bit(R5_ReadRepl
, &head_sh
->dev
[i
].flags
) && rrdev
)
940 if (rdev
&& test_bit(Faulty
, &rdev
->flags
))
943 atomic_inc(&rdev
->nr_pending
);
944 if (rrdev
&& test_bit(Faulty
, &rrdev
->flags
))
947 atomic_inc(&rrdev
->nr_pending
);
950 /* We have already checked bad blocks for reads. Now
951 * need to check for writes. We never accept write errors
952 * on the replacement, so we don't to check rrdev.
954 while ((rw
& WRITE
) && rdev
&&
955 test_bit(WriteErrorSeen
, &rdev
->flags
)) {
958 int bad
= is_badblock(rdev
, sh
->sector
, STRIPE_SECTORS
,
959 &first_bad
, &bad_sectors
);
964 set_bit(BlockedBadBlocks
, &rdev
->flags
);
965 if (!conf
->mddev
->external
&&
966 conf
->mddev
->flags
) {
967 /* It is very unlikely, but we might
968 * still need to write out the
969 * bad block log - better give it
971 md_check_recovery(conf
->mddev
);
974 * Because md_wait_for_blocked_rdev
975 * will dec nr_pending, we must
976 * increment it first.
978 atomic_inc(&rdev
->nr_pending
);
979 md_wait_for_blocked_rdev(rdev
, conf
->mddev
);
981 /* Acknowledged bad block - skip the write */
982 rdev_dec_pending(rdev
, conf
->mddev
);
988 if (s
->syncing
|| s
->expanding
|| s
->expanded
990 md_sync_acct(rdev
->bdev
, STRIPE_SECTORS
);
992 set_bit(STRIPE_IO_STARTED
, &sh
->state
);
995 bi
->bi_bdev
= rdev
->bdev
;
997 bi
->bi_end_io
= (rw
& WRITE
)
998 ? raid5_end_write_request
999 : raid5_end_read_request
;
1000 bi
->bi_private
= sh
;
1002 pr_debug("%s: for %llu schedule op %ld on disc %d\n",
1003 __func__
, (unsigned long long)sh
->sector
,
1005 atomic_inc(&sh
->count
);
1007 atomic_inc(&head_sh
->count
);
1008 if (use_new_offset(conf
, sh
))
1009 bi
->bi_iter
.bi_sector
= (sh
->sector
1010 + rdev
->new_data_offset
);
1012 bi
->bi_iter
.bi_sector
= (sh
->sector
1013 + rdev
->data_offset
);
1014 if (test_bit(R5_ReadNoMerge
, &head_sh
->dev
[i
].flags
))
1015 bi
->bi_rw
|= REQ_NOMERGE
;
1017 if (test_bit(R5_SkipCopy
, &sh
->dev
[i
].flags
))
1018 WARN_ON(test_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
));
1019 sh
->dev
[i
].vec
.bv_page
= sh
->dev
[i
].page
;
1021 bi
->bi_io_vec
[0].bv_len
= STRIPE_SIZE
;
1022 bi
->bi_io_vec
[0].bv_offset
= 0;
1023 bi
->bi_iter
.bi_size
= STRIPE_SIZE
;
1025 * If this is discard request, set bi_vcnt 0. We don't
1026 * want to confuse SCSI because SCSI will replace payload
1028 if (rw
& REQ_DISCARD
)
1031 set_bit(R5_DOUBLE_LOCKED
, &sh
->dev
[i
].flags
);
1033 if (conf
->mddev
->gendisk
)
1034 trace_block_bio_remap(bdev_get_queue(bi
->bi_bdev
),
1035 bi
, disk_devt(conf
->mddev
->gendisk
),
1037 generic_make_request(bi
);
1040 if (s
->syncing
|| s
->expanding
|| s
->expanded
1042 md_sync_acct(rrdev
->bdev
, STRIPE_SECTORS
);
1044 set_bit(STRIPE_IO_STARTED
, &sh
->state
);
1047 rbi
->bi_bdev
= rrdev
->bdev
;
1049 BUG_ON(!(rw
& WRITE
));
1050 rbi
->bi_end_io
= raid5_end_write_request
;
1051 rbi
->bi_private
= sh
;
1053 pr_debug("%s: for %llu schedule op %ld on "
1054 "replacement disc %d\n",
1055 __func__
, (unsigned long long)sh
->sector
,
1057 atomic_inc(&sh
->count
);
1059 atomic_inc(&head_sh
->count
);
1060 if (use_new_offset(conf
, sh
))
1061 rbi
->bi_iter
.bi_sector
= (sh
->sector
1062 + rrdev
->new_data_offset
);
1064 rbi
->bi_iter
.bi_sector
= (sh
->sector
1065 + rrdev
->data_offset
);
1066 if (test_bit(R5_SkipCopy
, &sh
->dev
[i
].flags
))
1067 WARN_ON(test_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
));
1068 sh
->dev
[i
].rvec
.bv_page
= sh
->dev
[i
].page
;
1070 rbi
->bi_io_vec
[0].bv_len
= STRIPE_SIZE
;
1071 rbi
->bi_io_vec
[0].bv_offset
= 0;
1072 rbi
->bi_iter
.bi_size
= STRIPE_SIZE
;
1074 * If this is discard request, set bi_vcnt 0. We don't
1075 * want to confuse SCSI because SCSI will replace payload
1077 if (rw
& REQ_DISCARD
)
1079 if (conf
->mddev
->gendisk
)
1080 trace_block_bio_remap(bdev_get_queue(rbi
->bi_bdev
),
1081 rbi
, disk_devt(conf
->mddev
->gendisk
),
1083 generic_make_request(rbi
);
1085 if (!rdev
&& !rrdev
) {
1087 set_bit(STRIPE_DEGRADED
, &sh
->state
);
1088 pr_debug("skip op %ld on disc %d for sector %llu\n",
1089 bi
->bi_rw
, i
, (unsigned long long)sh
->sector
);
1090 clear_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
1091 set_bit(STRIPE_HANDLE
, &sh
->state
);
1094 if (!head_sh
->batch_head
)
1096 sh
= list_first_entry(&sh
->batch_list
, struct stripe_head
,
1103 static struct dma_async_tx_descriptor
*
1104 async_copy_data(int frombio
, struct bio
*bio
, struct page
**page
,
1105 sector_t sector
, struct dma_async_tx_descriptor
*tx
,
1106 struct stripe_head
*sh
)
1109 struct bvec_iter iter
;
1110 struct page
*bio_page
;
1112 struct async_submit_ctl submit
;
1113 enum async_tx_flags flags
= 0;
1115 if (bio
->bi_iter
.bi_sector
>= sector
)
1116 page_offset
= (signed)(bio
->bi_iter
.bi_sector
- sector
) * 512;
1118 page_offset
= (signed)(sector
- bio
->bi_iter
.bi_sector
) * -512;
1121 flags
|= ASYNC_TX_FENCE
;
1122 init_async_submit(&submit
, flags
, tx
, NULL
, NULL
, NULL
);
1124 bio_for_each_segment(bvl
, bio
, iter
) {
1125 int len
= bvl
.bv_len
;
1129 if (page_offset
< 0) {
1130 b_offset
= -page_offset
;
1131 page_offset
+= b_offset
;
1135 if (len
> 0 && page_offset
+ len
> STRIPE_SIZE
)
1136 clen
= STRIPE_SIZE
- page_offset
;
1141 b_offset
+= bvl
.bv_offset
;
1142 bio_page
= bvl
.bv_page
;
1144 if (sh
->raid_conf
->skip_copy
&&
1145 b_offset
== 0 && page_offset
== 0 &&
1146 clen
== STRIPE_SIZE
)
1149 tx
= async_memcpy(*page
, bio_page
, page_offset
,
1150 b_offset
, clen
, &submit
);
1152 tx
= async_memcpy(bio_page
, *page
, b_offset
,
1153 page_offset
, clen
, &submit
);
1155 /* chain the operations */
1156 submit
.depend_tx
= tx
;
1158 if (clen
< len
) /* hit end of page */
1166 static void ops_complete_biofill(void *stripe_head_ref
)
1168 struct stripe_head
*sh
= stripe_head_ref
;
1169 struct bio
*return_bi
= NULL
;
1172 pr_debug("%s: stripe %llu\n", __func__
,
1173 (unsigned long long)sh
->sector
);
1175 /* clear completed biofills */
1176 for (i
= sh
->disks
; i
--; ) {
1177 struct r5dev
*dev
= &sh
->dev
[i
];
1179 /* acknowledge completion of a biofill operation */
1180 /* and check if we need to reply to a read request,
1181 * new R5_Wantfill requests are held off until
1182 * !STRIPE_BIOFILL_RUN
1184 if (test_and_clear_bit(R5_Wantfill
, &dev
->flags
)) {
1185 struct bio
*rbi
, *rbi2
;
1190 while (rbi
&& rbi
->bi_iter
.bi_sector
<
1191 dev
->sector
+ STRIPE_SECTORS
) {
1192 rbi2
= r5_next_bio(rbi
, dev
->sector
);
1193 if (!raid5_dec_bi_active_stripes(rbi
)) {
1194 rbi
->bi_next
= return_bi
;
1201 clear_bit(STRIPE_BIOFILL_RUN
, &sh
->state
);
1203 return_io(return_bi
);
1205 set_bit(STRIPE_HANDLE
, &sh
->state
);
1209 static void ops_run_biofill(struct stripe_head
*sh
)
1211 struct dma_async_tx_descriptor
*tx
= NULL
;
1212 struct async_submit_ctl submit
;
1215 BUG_ON(sh
->batch_head
);
1216 pr_debug("%s: stripe %llu\n", __func__
,
1217 (unsigned long long)sh
->sector
);
1219 for (i
= sh
->disks
; i
--; ) {
1220 struct r5dev
*dev
= &sh
->dev
[i
];
1221 if (test_bit(R5_Wantfill
, &dev
->flags
)) {
1223 spin_lock_irq(&sh
->stripe_lock
);
1224 dev
->read
= rbi
= dev
->toread
;
1226 spin_unlock_irq(&sh
->stripe_lock
);
1227 while (rbi
&& rbi
->bi_iter
.bi_sector
<
1228 dev
->sector
+ STRIPE_SECTORS
) {
1229 tx
= async_copy_data(0, rbi
, &dev
->page
,
1230 dev
->sector
, tx
, sh
);
1231 rbi
= r5_next_bio(rbi
, dev
->sector
);
1236 atomic_inc(&sh
->count
);
1237 init_async_submit(&submit
, ASYNC_TX_ACK
, tx
, ops_complete_biofill
, sh
, NULL
);
1238 async_trigger_callback(&submit
);
1241 static void mark_target_uptodate(struct stripe_head
*sh
, int target
)
1248 tgt
= &sh
->dev
[target
];
1249 set_bit(R5_UPTODATE
, &tgt
->flags
);
1250 BUG_ON(!test_bit(R5_Wantcompute
, &tgt
->flags
));
1251 clear_bit(R5_Wantcompute
, &tgt
->flags
);
1254 static void ops_complete_compute(void *stripe_head_ref
)
1256 struct stripe_head
*sh
= stripe_head_ref
;
1258 pr_debug("%s: stripe %llu\n", __func__
,
1259 (unsigned long long)sh
->sector
);
1261 /* mark the computed target(s) as uptodate */
1262 mark_target_uptodate(sh
, sh
->ops
.target
);
1263 mark_target_uptodate(sh
, sh
->ops
.target2
);
1265 clear_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
1266 if (sh
->check_state
== check_state_compute_run
)
1267 sh
->check_state
= check_state_compute_result
;
1268 set_bit(STRIPE_HANDLE
, &sh
->state
);
1272 /* return a pointer to the address conversion region of the scribble buffer */
1273 static addr_conv_t
*to_addr_conv(struct stripe_head
*sh
,
1274 struct raid5_percpu
*percpu
, int i
)
1278 addr
= flex_array_get(percpu
->scribble
, i
);
1279 return addr
+ sizeof(struct page
*) * (sh
->disks
+ 2);
1282 /* return a pointer to the address conversion region of the scribble buffer */
1283 static struct page
**to_addr_page(struct raid5_percpu
*percpu
, int i
)
1287 addr
= flex_array_get(percpu
->scribble
, i
);
1291 static struct dma_async_tx_descriptor
*
1292 ops_run_compute5(struct stripe_head
*sh
, struct raid5_percpu
*percpu
)
1294 int disks
= sh
->disks
;
1295 struct page
**xor_srcs
= to_addr_page(percpu
, 0);
1296 int target
= sh
->ops
.target
;
1297 struct r5dev
*tgt
= &sh
->dev
[target
];
1298 struct page
*xor_dest
= tgt
->page
;
1300 struct dma_async_tx_descriptor
*tx
;
1301 struct async_submit_ctl submit
;
1304 BUG_ON(sh
->batch_head
);
1306 pr_debug("%s: stripe %llu block: %d\n",
1307 __func__
, (unsigned long long)sh
->sector
, target
);
1308 BUG_ON(!test_bit(R5_Wantcompute
, &tgt
->flags
));
1310 for (i
= disks
; i
--; )
1312 xor_srcs
[count
++] = sh
->dev
[i
].page
;
1314 atomic_inc(&sh
->count
);
1316 init_async_submit(&submit
, ASYNC_TX_FENCE
|ASYNC_TX_XOR_ZERO_DST
, NULL
,
1317 ops_complete_compute
, sh
, to_addr_conv(sh
, percpu
, 0));
1318 if (unlikely(count
== 1))
1319 tx
= async_memcpy(xor_dest
, xor_srcs
[0], 0, 0, STRIPE_SIZE
, &submit
);
1321 tx
= async_xor(xor_dest
, xor_srcs
, 0, count
, STRIPE_SIZE
, &submit
);
1326 /* set_syndrome_sources - populate source buffers for gen_syndrome
1327 * @srcs - (struct page *) array of size sh->disks
1328 * @sh - stripe_head to parse
1330 * Populates srcs in proper layout order for the stripe and returns the
1331 * 'count' of sources to be used in a call to async_gen_syndrome. The P
1332 * destination buffer is recorded in srcs[count] and the Q destination
1333 * is recorded in srcs[count+1]].
1335 static int set_syndrome_sources(struct page
**srcs
,
1336 struct stripe_head
*sh
,
1339 int disks
= sh
->disks
;
1340 int syndrome_disks
= sh
->ddf_layout
? disks
: (disks
- 2);
1341 int d0_idx
= raid6_d0(sh
);
1345 for (i
= 0; i
< disks
; i
++)
1351 int slot
= raid6_idx_to_slot(i
, sh
, &count
, syndrome_disks
);
1352 struct r5dev
*dev
= &sh
->dev
[i
];
1354 if (i
== sh
->qd_idx
|| i
== sh
->pd_idx
||
1355 (srctype
== SYNDROME_SRC_ALL
) ||
1356 (srctype
== SYNDROME_SRC_WANT_DRAIN
&&
1357 test_bit(R5_Wantdrain
, &dev
->flags
)) ||
1358 (srctype
== SYNDROME_SRC_WRITTEN
&&
1360 srcs
[slot
] = sh
->dev
[i
].page
;
1361 i
= raid6_next_disk(i
, disks
);
1362 } while (i
!= d0_idx
);
1364 return syndrome_disks
;
1367 static struct dma_async_tx_descriptor
*
1368 ops_run_compute6_1(struct stripe_head
*sh
, struct raid5_percpu
*percpu
)
1370 int disks
= sh
->disks
;
1371 struct page
**blocks
= to_addr_page(percpu
, 0);
1373 int qd_idx
= sh
->qd_idx
;
1374 struct dma_async_tx_descriptor
*tx
;
1375 struct async_submit_ctl submit
;
1381 BUG_ON(sh
->batch_head
);
1382 if (sh
->ops
.target
< 0)
1383 target
= sh
->ops
.target2
;
1384 else if (sh
->ops
.target2
< 0)
1385 target
= sh
->ops
.target
;
1387 /* we should only have one valid target */
1390 pr_debug("%s: stripe %llu block: %d\n",
1391 __func__
, (unsigned long long)sh
->sector
, target
);
1393 tgt
= &sh
->dev
[target
];
1394 BUG_ON(!test_bit(R5_Wantcompute
, &tgt
->flags
));
1397 atomic_inc(&sh
->count
);
1399 if (target
== qd_idx
) {
1400 count
= set_syndrome_sources(blocks
, sh
, SYNDROME_SRC_ALL
);
1401 blocks
[count
] = NULL
; /* regenerating p is not necessary */
1402 BUG_ON(blocks
[count
+1] != dest
); /* q should already be set */
1403 init_async_submit(&submit
, ASYNC_TX_FENCE
, NULL
,
1404 ops_complete_compute
, sh
,
1405 to_addr_conv(sh
, percpu
, 0));
1406 tx
= async_gen_syndrome(blocks
, 0, count
+2, STRIPE_SIZE
, &submit
);
1408 /* Compute any data- or p-drive using XOR */
1410 for (i
= disks
; i
-- ; ) {
1411 if (i
== target
|| i
== qd_idx
)
1413 blocks
[count
++] = sh
->dev
[i
].page
;
1416 init_async_submit(&submit
, ASYNC_TX_FENCE
|ASYNC_TX_XOR_ZERO_DST
,
1417 NULL
, ops_complete_compute
, sh
,
1418 to_addr_conv(sh
, percpu
, 0));
1419 tx
= async_xor(dest
, blocks
, 0, count
, STRIPE_SIZE
, &submit
);
1425 static struct dma_async_tx_descriptor
*
1426 ops_run_compute6_2(struct stripe_head
*sh
, struct raid5_percpu
*percpu
)
1428 int i
, count
, disks
= sh
->disks
;
1429 int syndrome_disks
= sh
->ddf_layout
? disks
: disks
-2;
1430 int d0_idx
= raid6_d0(sh
);
1431 int faila
= -1, failb
= -1;
1432 int target
= sh
->ops
.target
;
1433 int target2
= sh
->ops
.target2
;
1434 struct r5dev
*tgt
= &sh
->dev
[target
];
1435 struct r5dev
*tgt2
= &sh
->dev
[target2
];
1436 struct dma_async_tx_descriptor
*tx
;
1437 struct page
**blocks
= to_addr_page(percpu
, 0);
1438 struct async_submit_ctl submit
;
1440 BUG_ON(sh
->batch_head
);
1441 pr_debug("%s: stripe %llu block1: %d block2: %d\n",
1442 __func__
, (unsigned long long)sh
->sector
, target
, target2
);
1443 BUG_ON(target
< 0 || target2
< 0);
1444 BUG_ON(!test_bit(R5_Wantcompute
, &tgt
->flags
));
1445 BUG_ON(!test_bit(R5_Wantcompute
, &tgt2
->flags
));
1447 /* we need to open-code set_syndrome_sources to handle the
1448 * slot number conversion for 'faila' and 'failb'
1450 for (i
= 0; i
< disks
; i
++)
1455 int slot
= raid6_idx_to_slot(i
, sh
, &count
, syndrome_disks
);
1457 blocks
[slot
] = sh
->dev
[i
].page
;
1463 i
= raid6_next_disk(i
, disks
);
1464 } while (i
!= d0_idx
);
1466 BUG_ON(faila
== failb
);
1469 pr_debug("%s: stripe: %llu faila: %d failb: %d\n",
1470 __func__
, (unsigned long long)sh
->sector
, faila
, failb
);
1472 atomic_inc(&sh
->count
);
1474 if (failb
== syndrome_disks
+1) {
1475 /* Q disk is one of the missing disks */
1476 if (faila
== syndrome_disks
) {
1477 /* Missing P+Q, just recompute */
1478 init_async_submit(&submit
, ASYNC_TX_FENCE
, NULL
,
1479 ops_complete_compute
, sh
,
1480 to_addr_conv(sh
, percpu
, 0));
1481 return async_gen_syndrome(blocks
, 0, syndrome_disks
+2,
1482 STRIPE_SIZE
, &submit
);
1486 int qd_idx
= sh
->qd_idx
;
1488 /* Missing D+Q: recompute D from P, then recompute Q */
1489 if (target
== qd_idx
)
1490 data_target
= target2
;
1492 data_target
= target
;
1495 for (i
= disks
; i
-- ; ) {
1496 if (i
== data_target
|| i
== qd_idx
)
1498 blocks
[count
++] = sh
->dev
[i
].page
;
1500 dest
= sh
->dev
[data_target
].page
;
1501 init_async_submit(&submit
,
1502 ASYNC_TX_FENCE
|ASYNC_TX_XOR_ZERO_DST
,
1504 to_addr_conv(sh
, percpu
, 0));
1505 tx
= async_xor(dest
, blocks
, 0, count
, STRIPE_SIZE
,
1508 count
= set_syndrome_sources(blocks
, sh
, SYNDROME_SRC_ALL
);
1509 init_async_submit(&submit
, ASYNC_TX_FENCE
, tx
,
1510 ops_complete_compute
, sh
,
1511 to_addr_conv(sh
, percpu
, 0));
1512 return async_gen_syndrome(blocks
, 0, count
+2,
1513 STRIPE_SIZE
, &submit
);
1516 init_async_submit(&submit
, ASYNC_TX_FENCE
, NULL
,
1517 ops_complete_compute
, sh
,
1518 to_addr_conv(sh
, percpu
, 0));
1519 if (failb
== syndrome_disks
) {
1520 /* We're missing D+P. */
1521 return async_raid6_datap_recov(syndrome_disks
+2,
1525 /* We're missing D+D. */
1526 return async_raid6_2data_recov(syndrome_disks
+2,
1527 STRIPE_SIZE
, faila
, failb
,
1533 static void ops_complete_prexor(void *stripe_head_ref
)
1535 struct stripe_head
*sh
= stripe_head_ref
;
1537 pr_debug("%s: stripe %llu\n", __func__
,
1538 (unsigned long long)sh
->sector
);
1541 static struct dma_async_tx_descriptor
*
1542 ops_run_prexor5(struct stripe_head
*sh
, struct raid5_percpu
*percpu
,
1543 struct dma_async_tx_descriptor
*tx
)
1545 int disks
= sh
->disks
;
1546 struct page
**xor_srcs
= to_addr_page(percpu
, 0);
1547 int count
= 0, pd_idx
= sh
->pd_idx
, i
;
1548 struct async_submit_ctl submit
;
1550 /* existing parity data subtracted */
1551 struct page
*xor_dest
= xor_srcs
[count
++] = sh
->dev
[pd_idx
].page
;
1553 BUG_ON(sh
->batch_head
);
1554 pr_debug("%s: stripe %llu\n", __func__
,
1555 (unsigned long long)sh
->sector
);
1557 for (i
= disks
; i
--; ) {
1558 struct r5dev
*dev
= &sh
->dev
[i
];
1559 /* Only process blocks that are known to be uptodate */
1560 if (test_bit(R5_Wantdrain
, &dev
->flags
))
1561 xor_srcs
[count
++] = dev
->page
;
1564 init_async_submit(&submit
, ASYNC_TX_FENCE
|ASYNC_TX_XOR_DROP_DST
, tx
,
1565 ops_complete_prexor
, sh
, to_addr_conv(sh
, percpu
, 0));
1566 tx
= async_xor(xor_dest
, xor_srcs
, 0, count
, STRIPE_SIZE
, &submit
);
1571 static struct dma_async_tx_descriptor
*
1572 ops_run_prexor6(struct stripe_head
*sh
, struct raid5_percpu
*percpu
,
1573 struct dma_async_tx_descriptor
*tx
)
1575 struct page
**blocks
= to_addr_page(percpu
, 0);
1577 struct async_submit_ctl submit
;
1579 pr_debug("%s: stripe %llu\n", __func__
,
1580 (unsigned long long)sh
->sector
);
1582 count
= set_syndrome_sources(blocks
, sh
, SYNDROME_SRC_WANT_DRAIN
);
1584 init_async_submit(&submit
, ASYNC_TX_FENCE
|ASYNC_TX_PQ_XOR_DST
, tx
,
1585 ops_complete_prexor
, sh
, to_addr_conv(sh
, percpu
, 0));
1586 tx
= async_gen_syndrome(blocks
, 0, count
+2, STRIPE_SIZE
, &submit
);
1591 static struct dma_async_tx_descriptor
*
1592 ops_run_biodrain(struct stripe_head
*sh
, struct dma_async_tx_descriptor
*tx
)
1594 int disks
= sh
->disks
;
1596 struct stripe_head
*head_sh
= sh
;
1598 pr_debug("%s: stripe %llu\n", __func__
,
1599 (unsigned long long)sh
->sector
);
1601 for (i
= disks
; i
--; ) {
1606 if (test_and_clear_bit(R5_Wantdrain
, &head_sh
->dev
[i
].flags
)) {
1611 spin_lock_irq(&sh
->stripe_lock
);
1612 chosen
= dev
->towrite
;
1613 dev
->towrite
= NULL
;
1614 sh
->overwrite_disks
= 0;
1615 BUG_ON(dev
->written
);
1616 wbi
= dev
->written
= chosen
;
1617 spin_unlock_irq(&sh
->stripe_lock
);
1618 WARN_ON(dev
->page
!= dev
->orig_page
);
1620 while (wbi
&& wbi
->bi_iter
.bi_sector
<
1621 dev
->sector
+ STRIPE_SECTORS
) {
1622 if (wbi
->bi_rw
& REQ_FUA
)
1623 set_bit(R5_WantFUA
, &dev
->flags
);
1624 if (wbi
->bi_rw
& REQ_SYNC
)
1625 set_bit(R5_SyncIO
, &dev
->flags
);
1626 if (wbi
->bi_rw
& REQ_DISCARD
)
1627 set_bit(R5_Discard
, &dev
->flags
);
1629 tx
= async_copy_data(1, wbi
, &dev
->page
,
1630 dev
->sector
, tx
, sh
);
1631 if (dev
->page
!= dev
->orig_page
) {
1632 set_bit(R5_SkipCopy
, &dev
->flags
);
1633 clear_bit(R5_UPTODATE
, &dev
->flags
);
1634 clear_bit(R5_OVERWRITE
, &dev
->flags
);
1637 wbi
= r5_next_bio(wbi
, dev
->sector
);
1640 if (head_sh
->batch_head
) {
1641 sh
= list_first_entry(&sh
->batch_list
,
1654 static void ops_complete_reconstruct(void *stripe_head_ref
)
1656 struct stripe_head
*sh
= stripe_head_ref
;
1657 int disks
= sh
->disks
;
1658 int pd_idx
= sh
->pd_idx
;
1659 int qd_idx
= sh
->qd_idx
;
1661 bool fua
= false, sync
= false, discard
= false;
1663 pr_debug("%s: stripe %llu\n", __func__
,
1664 (unsigned long long)sh
->sector
);
1666 for (i
= disks
; i
--; ) {
1667 fua
|= test_bit(R5_WantFUA
, &sh
->dev
[i
].flags
);
1668 sync
|= test_bit(R5_SyncIO
, &sh
->dev
[i
].flags
);
1669 discard
|= test_bit(R5_Discard
, &sh
->dev
[i
].flags
);
1672 for (i
= disks
; i
--; ) {
1673 struct r5dev
*dev
= &sh
->dev
[i
];
1675 if (dev
->written
|| i
== pd_idx
|| i
== qd_idx
) {
1676 if (!discard
&& !test_bit(R5_SkipCopy
, &dev
->flags
))
1677 set_bit(R5_UPTODATE
, &dev
->flags
);
1679 set_bit(R5_WantFUA
, &dev
->flags
);
1681 set_bit(R5_SyncIO
, &dev
->flags
);
1685 if (sh
->reconstruct_state
== reconstruct_state_drain_run
)
1686 sh
->reconstruct_state
= reconstruct_state_drain_result
;
1687 else if (sh
->reconstruct_state
== reconstruct_state_prexor_drain_run
)
1688 sh
->reconstruct_state
= reconstruct_state_prexor_drain_result
;
1690 BUG_ON(sh
->reconstruct_state
!= reconstruct_state_run
);
1691 sh
->reconstruct_state
= reconstruct_state_result
;
1694 set_bit(STRIPE_HANDLE
, &sh
->state
);
1699 ops_run_reconstruct5(struct stripe_head
*sh
, struct raid5_percpu
*percpu
,
1700 struct dma_async_tx_descriptor
*tx
)
1702 int disks
= sh
->disks
;
1703 struct page
**xor_srcs
;
1704 struct async_submit_ctl submit
;
1705 int count
, pd_idx
= sh
->pd_idx
, i
;
1706 struct page
*xor_dest
;
1708 unsigned long flags
;
1710 struct stripe_head
*head_sh
= sh
;
1713 pr_debug("%s: stripe %llu\n", __func__
,
1714 (unsigned long long)sh
->sector
);
1716 for (i
= 0; i
< sh
->disks
; i
++) {
1719 if (!test_bit(R5_Discard
, &sh
->dev
[i
].flags
))
1722 if (i
>= sh
->disks
) {
1723 atomic_inc(&sh
->count
);
1724 set_bit(R5_Discard
, &sh
->dev
[pd_idx
].flags
);
1725 ops_complete_reconstruct(sh
);
1730 xor_srcs
= to_addr_page(percpu
, j
);
1731 /* check if prexor is active which means only process blocks
1732 * that are part of a read-modify-write (written)
1734 if (head_sh
->reconstruct_state
== reconstruct_state_prexor_drain_run
) {
1736 xor_dest
= xor_srcs
[count
++] = sh
->dev
[pd_idx
].page
;
1737 for (i
= disks
; i
--; ) {
1738 struct r5dev
*dev
= &sh
->dev
[i
];
1739 if (head_sh
->dev
[i
].written
)
1740 xor_srcs
[count
++] = dev
->page
;
1743 xor_dest
= sh
->dev
[pd_idx
].page
;
1744 for (i
= disks
; i
--; ) {
1745 struct r5dev
*dev
= &sh
->dev
[i
];
1747 xor_srcs
[count
++] = dev
->page
;
1751 /* 1/ if we prexor'd then the dest is reused as a source
1752 * 2/ if we did not prexor then we are redoing the parity
1753 * set ASYNC_TX_XOR_DROP_DST and ASYNC_TX_XOR_ZERO_DST
1754 * for the synchronous xor case
1756 last_stripe
= !head_sh
->batch_head
||
1757 list_first_entry(&sh
->batch_list
,
1758 struct stripe_head
, batch_list
) == head_sh
;
1760 flags
= ASYNC_TX_ACK
|
1761 (prexor
? ASYNC_TX_XOR_DROP_DST
: ASYNC_TX_XOR_ZERO_DST
);
1763 atomic_inc(&head_sh
->count
);
1764 init_async_submit(&submit
, flags
, tx
, ops_complete_reconstruct
, head_sh
,
1765 to_addr_conv(sh
, percpu
, j
));
1767 flags
= prexor
? ASYNC_TX_XOR_DROP_DST
: ASYNC_TX_XOR_ZERO_DST
;
1768 init_async_submit(&submit
, flags
, tx
, NULL
, NULL
,
1769 to_addr_conv(sh
, percpu
, j
));
1772 if (unlikely(count
== 1))
1773 tx
= async_memcpy(xor_dest
, xor_srcs
[0], 0, 0, STRIPE_SIZE
, &submit
);
1775 tx
= async_xor(xor_dest
, xor_srcs
, 0, count
, STRIPE_SIZE
, &submit
);
1778 sh
= list_first_entry(&sh
->batch_list
, struct stripe_head
,
1785 ops_run_reconstruct6(struct stripe_head
*sh
, struct raid5_percpu
*percpu
,
1786 struct dma_async_tx_descriptor
*tx
)
1788 struct async_submit_ctl submit
;
1789 struct page
**blocks
;
1790 int count
, i
, j
= 0;
1791 struct stripe_head
*head_sh
= sh
;
1794 unsigned long txflags
;
1796 pr_debug("%s: stripe %llu\n", __func__
, (unsigned long long)sh
->sector
);
1798 for (i
= 0; i
< sh
->disks
; i
++) {
1799 if (sh
->pd_idx
== i
|| sh
->qd_idx
== i
)
1801 if (!test_bit(R5_Discard
, &sh
->dev
[i
].flags
))
1804 if (i
>= sh
->disks
) {
1805 atomic_inc(&sh
->count
);
1806 set_bit(R5_Discard
, &sh
->dev
[sh
->pd_idx
].flags
);
1807 set_bit(R5_Discard
, &sh
->dev
[sh
->qd_idx
].flags
);
1808 ops_complete_reconstruct(sh
);
1813 blocks
= to_addr_page(percpu
, j
);
1815 if (sh
->reconstruct_state
== reconstruct_state_prexor_drain_run
) {
1816 synflags
= SYNDROME_SRC_WRITTEN
;
1817 txflags
= ASYNC_TX_ACK
| ASYNC_TX_PQ_XOR_DST
;
1819 synflags
= SYNDROME_SRC_ALL
;
1820 txflags
= ASYNC_TX_ACK
;
1823 count
= set_syndrome_sources(blocks
, sh
, synflags
);
1824 last_stripe
= !head_sh
->batch_head
||
1825 list_first_entry(&sh
->batch_list
,
1826 struct stripe_head
, batch_list
) == head_sh
;
1829 atomic_inc(&head_sh
->count
);
1830 init_async_submit(&submit
, txflags
, tx
, ops_complete_reconstruct
,
1831 head_sh
, to_addr_conv(sh
, percpu
, j
));
1833 init_async_submit(&submit
, 0, tx
, NULL
, NULL
,
1834 to_addr_conv(sh
, percpu
, j
));
1835 tx
= async_gen_syndrome(blocks
, 0, count
+2, STRIPE_SIZE
, &submit
);
1838 sh
= list_first_entry(&sh
->batch_list
, struct stripe_head
,
1844 static void ops_complete_check(void *stripe_head_ref
)
1846 struct stripe_head
*sh
= stripe_head_ref
;
1848 pr_debug("%s: stripe %llu\n", __func__
,
1849 (unsigned long long)sh
->sector
);
1851 sh
->check_state
= check_state_check_result
;
1852 set_bit(STRIPE_HANDLE
, &sh
->state
);
1856 static void ops_run_check_p(struct stripe_head
*sh
, struct raid5_percpu
*percpu
)
1858 int disks
= sh
->disks
;
1859 int pd_idx
= sh
->pd_idx
;
1860 int qd_idx
= sh
->qd_idx
;
1861 struct page
*xor_dest
;
1862 struct page
**xor_srcs
= to_addr_page(percpu
, 0);
1863 struct dma_async_tx_descriptor
*tx
;
1864 struct async_submit_ctl submit
;
1868 pr_debug("%s: stripe %llu\n", __func__
,
1869 (unsigned long long)sh
->sector
);
1871 BUG_ON(sh
->batch_head
);
1873 xor_dest
= sh
->dev
[pd_idx
].page
;
1874 xor_srcs
[count
++] = xor_dest
;
1875 for (i
= disks
; i
--; ) {
1876 if (i
== pd_idx
|| i
== qd_idx
)
1878 xor_srcs
[count
++] = sh
->dev
[i
].page
;
1881 init_async_submit(&submit
, 0, NULL
, NULL
, NULL
,
1882 to_addr_conv(sh
, percpu
, 0));
1883 tx
= async_xor_val(xor_dest
, xor_srcs
, 0, count
, STRIPE_SIZE
,
1884 &sh
->ops
.zero_sum_result
, &submit
);
1886 atomic_inc(&sh
->count
);
1887 init_async_submit(&submit
, ASYNC_TX_ACK
, tx
, ops_complete_check
, sh
, NULL
);
1888 tx
= async_trigger_callback(&submit
);
1891 static void ops_run_check_pq(struct stripe_head
*sh
, struct raid5_percpu
*percpu
, int checkp
)
1893 struct page
**srcs
= to_addr_page(percpu
, 0);
1894 struct async_submit_ctl submit
;
1897 pr_debug("%s: stripe %llu checkp: %d\n", __func__
,
1898 (unsigned long long)sh
->sector
, checkp
);
1900 BUG_ON(sh
->batch_head
);
1901 count
= set_syndrome_sources(srcs
, sh
, SYNDROME_SRC_ALL
);
1905 atomic_inc(&sh
->count
);
1906 init_async_submit(&submit
, ASYNC_TX_ACK
, NULL
, ops_complete_check
,
1907 sh
, to_addr_conv(sh
, percpu
, 0));
1908 async_syndrome_val(srcs
, 0, count
+2, STRIPE_SIZE
,
1909 &sh
->ops
.zero_sum_result
, percpu
->spare_page
, &submit
);
1912 static void raid_run_ops(struct stripe_head
*sh
, unsigned long ops_request
)
1914 int overlap_clear
= 0, i
, disks
= sh
->disks
;
1915 struct dma_async_tx_descriptor
*tx
= NULL
;
1916 struct r5conf
*conf
= sh
->raid_conf
;
1917 int level
= conf
->level
;
1918 struct raid5_percpu
*percpu
;
1922 percpu
= per_cpu_ptr(conf
->percpu
, cpu
);
1923 if (test_bit(STRIPE_OP_BIOFILL
, &ops_request
)) {
1924 ops_run_biofill(sh
);
1928 if (test_bit(STRIPE_OP_COMPUTE_BLK
, &ops_request
)) {
1930 tx
= ops_run_compute5(sh
, percpu
);
1932 if (sh
->ops
.target2
< 0 || sh
->ops
.target
< 0)
1933 tx
= ops_run_compute6_1(sh
, percpu
);
1935 tx
= ops_run_compute6_2(sh
, percpu
);
1937 /* terminate the chain if reconstruct is not set to be run */
1938 if (tx
&& !test_bit(STRIPE_OP_RECONSTRUCT
, &ops_request
))
1942 if (test_bit(STRIPE_OP_PREXOR
, &ops_request
)) {
1944 tx
= ops_run_prexor5(sh
, percpu
, tx
);
1946 tx
= ops_run_prexor6(sh
, percpu
, tx
);
1949 if (test_bit(STRIPE_OP_BIODRAIN
, &ops_request
)) {
1950 tx
= ops_run_biodrain(sh
, tx
);
1954 if (test_bit(STRIPE_OP_RECONSTRUCT
, &ops_request
)) {
1956 ops_run_reconstruct5(sh
, percpu
, tx
);
1958 ops_run_reconstruct6(sh
, percpu
, tx
);
1961 if (test_bit(STRIPE_OP_CHECK
, &ops_request
)) {
1962 if (sh
->check_state
== check_state_run
)
1963 ops_run_check_p(sh
, percpu
);
1964 else if (sh
->check_state
== check_state_run_q
)
1965 ops_run_check_pq(sh
, percpu
, 0);
1966 else if (sh
->check_state
== check_state_run_pq
)
1967 ops_run_check_pq(sh
, percpu
, 1);
1972 if (overlap_clear
&& !sh
->batch_head
)
1973 for (i
= disks
; i
--; ) {
1974 struct r5dev
*dev
= &sh
->dev
[i
];
1975 if (test_and_clear_bit(R5_Overlap
, &dev
->flags
))
1976 wake_up(&sh
->raid_conf
->wait_for_overlap
);
1981 static struct stripe_head
*alloc_stripe(struct kmem_cache
*sc
, gfp_t gfp
)
1983 struct stripe_head
*sh
;
1985 sh
= kmem_cache_zalloc(sc
, gfp
);
1987 spin_lock_init(&sh
->stripe_lock
);
1988 spin_lock_init(&sh
->batch_lock
);
1989 INIT_LIST_HEAD(&sh
->batch_list
);
1990 INIT_LIST_HEAD(&sh
->lru
);
1991 atomic_set(&sh
->count
, 1);
1995 static int grow_one_stripe(struct r5conf
*conf
, gfp_t gfp
)
1997 struct stripe_head
*sh
;
1999 sh
= alloc_stripe(conf
->slab_cache
, gfp
);
2003 sh
->raid_conf
= conf
;
2005 if (grow_buffers(sh
, gfp
)) {
2007 kmem_cache_free(conf
->slab_cache
, sh
);
2010 sh
->hash_lock_index
=
2011 conf
->max_nr_stripes
% NR_STRIPE_HASH_LOCKS
;
2012 /* we just created an active stripe so... */
2013 atomic_inc(&conf
->active_stripes
);
2016 conf
->max_nr_stripes
++;
2020 static int grow_stripes(struct r5conf
*conf
, int num
)
2022 struct kmem_cache
*sc
;
2023 int devs
= max(conf
->raid_disks
, conf
->previous_raid_disks
);
2025 if (conf
->mddev
->gendisk
)
2026 sprintf(conf
->cache_name
[0],
2027 "raid%d-%s", conf
->level
, mdname(conf
->mddev
));
2029 sprintf(conf
->cache_name
[0],
2030 "raid%d-%p", conf
->level
, conf
->mddev
);
2031 sprintf(conf
->cache_name
[1], "%s-alt", conf
->cache_name
[0]);
2033 conf
->active_name
= 0;
2034 sc
= kmem_cache_create(conf
->cache_name
[conf
->active_name
],
2035 sizeof(struct stripe_head
)+(devs
-1)*sizeof(struct r5dev
),
2039 conf
->slab_cache
= sc
;
2040 conf
->pool_size
= devs
;
2042 if (!grow_one_stripe(conf
, GFP_KERNEL
))
2049 * scribble_len - return the required size of the scribble region
2050 * @num - total number of disks in the array
2052 * The size must be enough to contain:
2053 * 1/ a struct page pointer for each device in the array +2
2054 * 2/ room to convert each entry in (1) to its corresponding dma
2055 * (dma_map_page()) or page (page_address()) address.
2057 * Note: the +2 is for the destination buffers of the ddf/raid6 case where we
2058 * calculate over all devices (not just the data blocks), using zeros in place
2059 * of the P and Q blocks.
2061 static struct flex_array
*scribble_alloc(int num
, int cnt
, gfp_t flags
)
2063 struct flex_array
*ret
;
2066 len
= sizeof(struct page
*) * (num
+2) + sizeof(addr_conv_t
) * (num
+2);
2067 ret
= flex_array_alloc(len
, cnt
, flags
);
2070 /* always prealloc all elements, so no locking is required */
2071 if (flex_array_prealloc(ret
, 0, cnt
, flags
)) {
2072 flex_array_free(ret
);
2078 static int resize_chunks(struct r5conf
*conf
, int new_disks
, int new_sectors
)
2083 mddev_suspend(conf
->mddev
);
2085 for_each_present_cpu(cpu
) {
2086 struct raid5_percpu
*percpu
;
2087 struct flex_array
*scribble
;
2089 percpu
= per_cpu_ptr(conf
->percpu
, cpu
);
2090 scribble
= scribble_alloc(new_disks
,
2091 new_sectors
/ STRIPE_SECTORS
,
2095 flex_array_free(percpu
->scribble
);
2096 percpu
->scribble
= scribble
;
2103 mddev_resume(conf
->mddev
);
2107 static int resize_stripes(struct r5conf
*conf
, int newsize
)
2109 /* Make all the stripes able to hold 'newsize' devices.
2110 * New slots in each stripe get 'page' set to a new page.
2112 * This happens in stages:
2113 * 1/ create a new kmem_cache and allocate the required number of
2115 * 2/ gather all the old stripe_heads and transfer the pages across
2116 * to the new stripe_heads. This will have the side effect of
2117 * freezing the array as once all stripe_heads have been collected,
2118 * no IO will be possible. Old stripe heads are freed once their
2119 * pages have been transferred over, and the old kmem_cache is
2120 * freed when all stripes are done.
2121 * 3/ reallocate conf->disks to be suitable bigger. If this fails,
2122 * we simple return a failre status - no need to clean anything up.
2123 * 4/ allocate new pages for the new slots in the new stripe_heads.
2124 * If this fails, we don't bother trying the shrink the
2125 * stripe_heads down again, we just leave them as they are.
2126 * As each stripe_head is processed the new one is released into
2129 * Once step2 is started, we cannot afford to wait for a write,
2130 * so we use GFP_NOIO allocations.
2132 struct stripe_head
*osh
, *nsh
;
2133 LIST_HEAD(newstripes
);
2134 struct disk_info
*ndisks
;
2136 struct kmem_cache
*sc
;
2140 if (newsize
<= conf
->pool_size
)
2141 return 0; /* never bother to shrink */
2143 err
= md_allow_write(conf
->mddev
);
2148 sc
= kmem_cache_create(conf
->cache_name
[1-conf
->active_name
],
2149 sizeof(struct stripe_head
)+(newsize
-1)*sizeof(struct r5dev
),
2154 for (i
= conf
->max_nr_stripes
; i
; i
--) {
2155 nsh
= alloc_stripe(sc
, GFP_KERNEL
);
2159 nsh
->raid_conf
= conf
;
2160 list_add(&nsh
->lru
, &newstripes
);
2163 /* didn't get enough, give up */
2164 while (!list_empty(&newstripes
)) {
2165 nsh
= list_entry(newstripes
.next
, struct stripe_head
, lru
);
2166 list_del(&nsh
->lru
);
2167 kmem_cache_free(sc
, nsh
);
2169 kmem_cache_destroy(sc
);
2172 /* Step 2 - Must use GFP_NOIO now.
2173 * OK, we have enough stripes, start collecting inactive
2174 * stripes and copying them over
2178 list_for_each_entry(nsh
, &newstripes
, lru
) {
2179 lock_device_hash_lock(conf
, hash
);
2180 wait_event_cmd(conf
->wait_for_stripe
,
2181 !list_empty(conf
->inactive_list
+ hash
),
2182 unlock_device_hash_lock(conf
, hash
),
2183 lock_device_hash_lock(conf
, hash
));
2184 osh
= get_free_stripe(conf
, hash
);
2185 unlock_device_hash_lock(conf
, hash
);
2187 for(i
=0; i
<conf
->pool_size
; i
++) {
2188 nsh
->dev
[i
].page
= osh
->dev
[i
].page
;
2189 nsh
->dev
[i
].orig_page
= osh
->dev
[i
].page
;
2191 nsh
->hash_lock_index
= hash
;
2192 kmem_cache_free(conf
->slab_cache
, osh
);
2194 if (cnt
>= conf
->max_nr_stripes
/ NR_STRIPE_HASH_LOCKS
+
2195 !!((conf
->max_nr_stripes
% NR_STRIPE_HASH_LOCKS
) > hash
)) {
2200 kmem_cache_destroy(conf
->slab_cache
);
2203 * At this point, we are holding all the stripes so the array
2204 * is completely stalled, so now is a good time to resize
2205 * conf->disks and the scribble region
2207 ndisks
= kzalloc(newsize
* sizeof(struct disk_info
), GFP_NOIO
);
2209 for (i
=0; i
<conf
->raid_disks
; i
++)
2210 ndisks
[i
] = conf
->disks
[i
];
2212 conf
->disks
= ndisks
;
2216 /* Step 4, return new stripes to service */
2217 while(!list_empty(&newstripes
)) {
2218 nsh
= list_entry(newstripes
.next
, struct stripe_head
, lru
);
2219 list_del_init(&nsh
->lru
);
2221 for (i
=conf
->raid_disks
; i
< newsize
; i
++)
2222 if (nsh
->dev
[i
].page
== NULL
) {
2223 struct page
*p
= alloc_page(GFP_NOIO
);
2224 nsh
->dev
[i
].page
= p
;
2225 nsh
->dev
[i
].orig_page
= p
;
2229 release_stripe(nsh
);
2231 /* critical section pass, GFP_NOIO no longer needed */
2233 conf
->slab_cache
= sc
;
2234 conf
->active_name
= 1-conf
->active_name
;
2236 conf
->pool_size
= newsize
;
2240 static int drop_one_stripe(struct r5conf
*conf
)
2242 struct stripe_head
*sh
;
2243 int hash
= (conf
->max_nr_stripes
- 1) % NR_STRIPE_HASH_LOCKS
;
2245 spin_lock_irq(conf
->hash_locks
+ hash
);
2246 sh
= get_free_stripe(conf
, hash
);
2247 spin_unlock_irq(conf
->hash_locks
+ hash
);
2250 BUG_ON(atomic_read(&sh
->count
));
2252 kmem_cache_free(conf
->slab_cache
, sh
);
2253 atomic_dec(&conf
->active_stripes
);
2254 conf
->max_nr_stripes
--;
2258 static void shrink_stripes(struct r5conf
*conf
)
2260 while (conf
->max_nr_stripes
&&
2261 drop_one_stripe(conf
))
2264 if (conf
->slab_cache
)
2265 kmem_cache_destroy(conf
->slab_cache
);
2266 conf
->slab_cache
= NULL
;
2269 static void raid5_end_read_request(struct bio
* bi
, int error
)
2271 struct stripe_head
*sh
= bi
->bi_private
;
2272 struct r5conf
*conf
= sh
->raid_conf
;
2273 int disks
= sh
->disks
, i
;
2274 int uptodate
= test_bit(BIO_UPTODATE
, &bi
->bi_flags
);
2275 char b
[BDEVNAME_SIZE
];
2276 struct md_rdev
*rdev
= NULL
;
2279 for (i
=0 ; i
<disks
; i
++)
2280 if (bi
== &sh
->dev
[i
].req
)
2283 pr_debug("end_read_request %llu/%d, count: %d, uptodate %d.\n",
2284 (unsigned long long)sh
->sector
, i
, atomic_read(&sh
->count
),
2290 if (test_bit(R5_ReadRepl
, &sh
->dev
[i
].flags
))
2291 /* If replacement finished while this request was outstanding,
2292 * 'replacement' might be NULL already.
2293 * In that case it moved down to 'rdev'.
2294 * rdev is not removed until all requests are finished.
2296 rdev
= conf
->disks
[i
].replacement
;
2298 rdev
= conf
->disks
[i
].rdev
;
2300 if (use_new_offset(conf
, sh
))
2301 s
= sh
->sector
+ rdev
->new_data_offset
;
2303 s
= sh
->sector
+ rdev
->data_offset
;
2305 set_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
);
2306 if (test_bit(R5_ReadError
, &sh
->dev
[i
].flags
)) {
2307 /* Note that this cannot happen on a
2308 * replacement device. We just fail those on
2313 "md/raid:%s: read error corrected"
2314 " (%lu sectors at %llu on %s)\n",
2315 mdname(conf
->mddev
), STRIPE_SECTORS
,
2316 (unsigned long long)s
,
2317 bdevname(rdev
->bdev
, b
));
2318 atomic_add(STRIPE_SECTORS
, &rdev
->corrected_errors
);
2319 clear_bit(R5_ReadError
, &sh
->dev
[i
].flags
);
2320 clear_bit(R5_ReWrite
, &sh
->dev
[i
].flags
);
2321 } else if (test_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
))
2322 clear_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
);
2324 if (atomic_read(&rdev
->read_errors
))
2325 atomic_set(&rdev
->read_errors
, 0);
2327 const char *bdn
= bdevname(rdev
->bdev
, b
);
2331 clear_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
);
2332 atomic_inc(&rdev
->read_errors
);
2333 if (test_bit(R5_ReadRepl
, &sh
->dev
[i
].flags
))
2336 "md/raid:%s: read error on replacement device "
2337 "(sector %llu on %s).\n",
2338 mdname(conf
->mddev
),
2339 (unsigned long long)s
,
2341 else if (conf
->mddev
->degraded
>= conf
->max_degraded
) {
2345 "md/raid:%s: read error not correctable "
2346 "(sector %llu on %s).\n",
2347 mdname(conf
->mddev
),
2348 (unsigned long long)s
,
2350 } else if (test_bit(R5_ReWrite
, &sh
->dev
[i
].flags
)) {
2355 "md/raid:%s: read error NOT corrected!! "
2356 "(sector %llu on %s).\n",
2357 mdname(conf
->mddev
),
2358 (unsigned long long)s
,
2360 } else if (atomic_read(&rdev
->read_errors
)
2361 > conf
->max_nr_stripes
)
2363 "md/raid:%s: Too many read errors, failing device %s.\n",
2364 mdname(conf
->mddev
), bdn
);
2367 if (set_bad
&& test_bit(In_sync
, &rdev
->flags
)
2368 && !test_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
))
2371 if (test_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
)) {
2372 set_bit(R5_ReadError
, &sh
->dev
[i
].flags
);
2373 clear_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
);
2375 set_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
);
2377 clear_bit(R5_ReadError
, &sh
->dev
[i
].flags
);
2378 clear_bit(R5_ReWrite
, &sh
->dev
[i
].flags
);
2380 && test_bit(In_sync
, &rdev
->flags
)
2381 && rdev_set_badblocks(
2382 rdev
, sh
->sector
, STRIPE_SECTORS
, 0)))
2383 md_error(conf
->mddev
, rdev
);
2386 rdev_dec_pending(rdev
, conf
->mddev
);
2387 clear_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
2388 set_bit(STRIPE_HANDLE
, &sh
->state
);
2392 static void raid5_end_write_request(struct bio
*bi
, int error
)
2394 struct stripe_head
*sh
= bi
->bi_private
;
2395 struct r5conf
*conf
= sh
->raid_conf
;
2396 int disks
= sh
->disks
, i
;
2397 struct md_rdev
*uninitialized_var(rdev
);
2398 int uptodate
= test_bit(BIO_UPTODATE
, &bi
->bi_flags
);
2401 int replacement
= 0;
2403 for (i
= 0 ; i
< disks
; i
++) {
2404 if (bi
== &sh
->dev
[i
].req
) {
2405 rdev
= conf
->disks
[i
].rdev
;
2408 if (bi
== &sh
->dev
[i
].rreq
) {
2409 rdev
= conf
->disks
[i
].replacement
;
2413 /* rdev was removed and 'replacement'
2414 * replaced it. rdev is not removed
2415 * until all requests are finished.
2417 rdev
= conf
->disks
[i
].rdev
;
2421 pr_debug("end_write_request %llu/%d, count %d, uptodate: %d.\n",
2422 (unsigned long long)sh
->sector
, i
, atomic_read(&sh
->count
),
2431 md_error(conf
->mddev
, rdev
);
2432 else if (is_badblock(rdev
, sh
->sector
,
2434 &first_bad
, &bad_sectors
))
2435 set_bit(R5_MadeGoodRepl
, &sh
->dev
[i
].flags
);
2438 set_bit(STRIPE_DEGRADED
, &sh
->state
);
2439 set_bit(WriteErrorSeen
, &rdev
->flags
);
2440 set_bit(R5_WriteError
, &sh
->dev
[i
].flags
);
2441 if (!test_and_set_bit(WantReplacement
, &rdev
->flags
))
2442 set_bit(MD_RECOVERY_NEEDED
,
2443 &rdev
->mddev
->recovery
);
2444 } else if (is_badblock(rdev
, sh
->sector
,
2446 &first_bad
, &bad_sectors
)) {
2447 set_bit(R5_MadeGood
, &sh
->dev
[i
].flags
);
2448 if (test_bit(R5_ReadError
, &sh
->dev
[i
].flags
))
2449 /* That was a successful write so make
2450 * sure it looks like we already did
2453 set_bit(R5_ReWrite
, &sh
->dev
[i
].flags
);
2456 rdev_dec_pending(rdev
, conf
->mddev
);
2458 if (sh
->batch_head
&& !uptodate
&& !replacement
)
2459 set_bit(STRIPE_BATCH_ERR
, &sh
->batch_head
->state
);
2461 if (!test_and_clear_bit(R5_DOUBLE_LOCKED
, &sh
->dev
[i
].flags
))
2462 clear_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
2463 set_bit(STRIPE_HANDLE
, &sh
->state
);
2466 if (sh
->batch_head
&& sh
!= sh
->batch_head
)
2467 release_stripe(sh
->batch_head
);
2470 static sector_t
compute_blocknr(struct stripe_head
*sh
, int i
, int previous
);
2472 static void raid5_build_block(struct stripe_head
*sh
, int i
, int previous
)
2474 struct r5dev
*dev
= &sh
->dev
[i
];
2476 bio_init(&dev
->req
);
2477 dev
->req
.bi_io_vec
= &dev
->vec
;
2478 dev
->req
.bi_max_vecs
= 1;
2479 dev
->req
.bi_private
= sh
;
2481 bio_init(&dev
->rreq
);
2482 dev
->rreq
.bi_io_vec
= &dev
->rvec
;
2483 dev
->rreq
.bi_max_vecs
= 1;
2484 dev
->rreq
.bi_private
= sh
;
2487 dev
->sector
= compute_blocknr(sh
, i
, previous
);
2490 static void error(struct mddev
*mddev
, struct md_rdev
*rdev
)
2492 char b
[BDEVNAME_SIZE
];
2493 struct r5conf
*conf
= mddev
->private;
2494 unsigned long flags
;
2495 pr_debug("raid456: error called\n");
2497 spin_lock_irqsave(&conf
->device_lock
, flags
);
2498 clear_bit(In_sync
, &rdev
->flags
);
2499 mddev
->degraded
= calc_degraded(conf
);
2500 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
2501 set_bit(MD_RECOVERY_INTR
, &mddev
->recovery
);
2503 set_bit(Blocked
, &rdev
->flags
);
2504 set_bit(Faulty
, &rdev
->flags
);
2505 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
2507 "md/raid:%s: Disk failure on %s, disabling device.\n"
2508 "md/raid:%s: Operation continuing on %d devices.\n",
2510 bdevname(rdev
->bdev
, b
),
2512 conf
->raid_disks
- mddev
->degraded
);
2516 * Input: a 'big' sector number,
2517 * Output: index of the data and parity disk, and the sector # in them.
2519 static sector_t
raid5_compute_sector(struct r5conf
*conf
, sector_t r_sector
,
2520 int previous
, int *dd_idx
,
2521 struct stripe_head
*sh
)
2523 sector_t stripe
, stripe2
;
2524 sector_t chunk_number
;
2525 unsigned int chunk_offset
;
2528 sector_t new_sector
;
2529 int algorithm
= previous
? conf
->prev_algo
2531 int sectors_per_chunk
= previous
? conf
->prev_chunk_sectors
2532 : conf
->chunk_sectors
;
2533 int raid_disks
= previous
? conf
->previous_raid_disks
2535 int data_disks
= raid_disks
- conf
->max_degraded
;
2537 /* First compute the information on this sector */
2540 * Compute the chunk number and the sector offset inside the chunk
2542 chunk_offset
= sector_div(r_sector
, sectors_per_chunk
);
2543 chunk_number
= r_sector
;
2546 * Compute the stripe number
2548 stripe
= chunk_number
;
2549 *dd_idx
= sector_div(stripe
, data_disks
);
2552 * Select the parity disk based on the user selected algorithm.
2554 pd_idx
= qd_idx
= -1;
2555 switch(conf
->level
) {
2557 pd_idx
= data_disks
;
2560 switch (algorithm
) {
2561 case ALGORITHM_LEFT_ASYMMETRIC
:
2562 pd_idx
= data_disks
- sector_div(stripe2
, raid_disks
);
2563 if (*dd_idx
>= pd_idx
)
2566 case ALGORITHM_RIGHT_ASYMMETRIC
:
2567 pd_idx
= sector_div(stripe2
, raid_disks
);
2568 if (*dd_idx
>= pd_idx
)
2571 case ALGORITHM_LEFT_SYMMETRIC
:
2572 pd_idx
= data_disks
- sector_div(stripe2
, raid_disks
);
2573 *dd_idx
= (pd_idx
+ 1 + *dd_idx
) % raid_disks
;
2575 case ALGORITHM_RIGHT_SYMMETRIC
:
2576 pd_idx
= sector_div(stripe2
, raid_disks
);
2577 *dd_idx
= (pd_idx
+ 1 + *dd_idx
) % raid_disks
;
2579 case ALGORITHM_PARITY_0
:
2583 case ALGORITHM_PARITY_N
:
2584 pd_idx
= data_disks
;
2592 switch (algorithm
) {
2593 case ALGORITHM_LEFT_ASYMMETRIC
:
2594 pd_idx
= raid_disks
- 1 - sector_div(stripe2
, raid_disks
);
2595 qd_idx
= pd_idx
+ 1;
2596 if (pd_idx
== raid_disks
-1) {
2597 (*dd_idx
)++; /* Q D D D P */
2599 } else if (*dd_idx
>= pd_idx
)
2600 (*dd_idx
) += 2; /* D D P Q D */
2602 case ALGORITHM_RIGHT_ASYMMETRIC
:
2603 pd_idx
= sector_div(stripe2
, raid_disks
);
2604 qd_idx
= pd_idx
+ 1;
2605 if (pd_idx
== raid_disks
-1) {
2606 (*dd_idx
)++; /* Q D D D P */
2608 } else if (*dd_idx
>= pd_idx
)
2609 (*dd_idx
) += 2; /* D D P Q D */
2611 case ALGORITHM_LEFT_SYMMETRIC
:
2612 pd_idx
= raid_disks
- 1 - sector_div(stripe2
, raid_disks
);
2613 qd_idx
= (pd_idx
+ 1) % raid_disks
;
2614 *dd_idx
= (pd_idx
+ 2 + *dd_idx
) % raid_disks
;
2616 case ALGORITHM_RIGHT_SYMMETRIC
:
2617 pd_idx
= sector_div(stripe2
, raid_disks
);
2618 qd_idx
= (pd_idx
+ 1) % raid_disks
;
2619 *dd_idx
= (pd_idx
+ 2 + *dd_idx
) % raid_disks
;
2622 case ALGORITHM_PARITY_0
:
2627 case ALGORITHM_PARITY_N
:
2628 pd_idx
= data_disks
;
2629 qd_idx
= data_disks
+ 1;
2632 case ALGORITHM_ROTATING_ZERO_RESTART
:
2633 /* Exactly the same as RIGHT_ASYMMETRIC, but or
2634 * of blocks for computing Q is different.
2636 pd_idx
= sector_div(stripe2
, raid_disks
);
2637 qd_idx
= pd_idx
+ 1;
2638 if (pd_idx
== raid_disks
-1) {
2639 (*dd_idx
)++; /* Q D D D P */
2641 } else if (*dd_idx
>= pd_idx
)
2642 (*dd_idx
) += 2; /* D D P Q D */
2646 case ALGORITHM_ROTATING_N_RESTART
:
2647 /* Same a left_asymmetric, by first stripe is
2648 * D D D P Q rather than
2652 pd_idx
= raid_disks
- 1 - sector_div(stripe2
, raid_disks
);
2653 qd_idx
= pd_idx
+ 1;
2654 if (pd_idx
== raid_disks
-1) {
2655 (*dd_idx
)++; /* Q D D D P */
2657 } else if (*dd_idx
>= pd_idx
)
2658 (*dd_idx
) += 2; /* D D P Q D */
2662 case ALGORITHM_ROTATING_N_CONTINUE
:
2663 /* Same as left_symmetric but Q is before P */
2664 pd_idx
= raid_disks
- 1 - sector_div(stripe2
, raid_disks
);
2665 qd_idx
= (pd_idx
+ raid_disks
- 1) % raid_disks
;
2666 *dd_idx
= (pd_idx
+ 1 + *dd_idx
) % raid_disks
;
2670 case ALGORITHM_LEFT_ASYMMETRIC_6
:
2671 /* RAID5 left_asymmetric, with Q on last device */
2672 pd_idx
= data_disks
- sector_div(stripe2
, raid_disks
-1);
2673 if (*dd_idx
>= pd_idx
)
2675 qd_idx
= raid_disks
- 1;
2678 case ALGORITHM_RIGHT_ASYMMETRIC_6
:
2679 pd_idx
= sector_div(stripe2
, raid_disks
-1);
2680 if (*dd_idx
>= pd_idx
)
2682 qd_idx
= raid_disks
- 1;
2685 case ALGORITHM_LEFT_SYMMETRIC_6
:
2686 pd_idx
= data_disks
- sector_div(stripe2
, raid_disks
-1);
2687 *dd_idx
= (pd_idx
+ 1 + *dd_idx
) % (raid_disks
-1);
2688 qd_idx
= raid_disks
- 1;
2691 case ALGORITHM_RIGHT_SYMMETRIC_6
:
2692 pd_idx
= sector_div(stripe2
, raid_disks
-1);
2693 *dd_idx
= (pd_idx
+ 1 + *dd_idx
) % (raid_disks
-1);
2694 qd_idx
= raid_disks
- 1;
2697 case ALGORITHM_PARITY_0_6
:
2700 qd_idx
= raid_disks
- 1;
2710 sh
->pd_idx
= pd_idx
;
2711 sh
->qd_idx
= qd_idx
;
2712 sh
->ddf_layout
= ddf_layout
;
2715 * Finally, compute the new sector number
2717 new_sector
= (sector_t
)stripe
* sectors_per_chunk
+ chunk_offset
;
2721 static sector_t
compute_blocknr(struct stripe_head
*sh
, int i
, int previous
)
2723 struct r5conf
*conf
= sh
->raid_conf
;
2724 int raid_disks
= sh
->disks
;
2725 int data_disks
= raid_disks
- conf
->max_degraded
;
2726 sector_t new_sector
= sh
->sector
, check
;
2727 int sectors_per_chunk
= previous
? conf
->prev_chunk_sectors
2728 : conf
->chunk_sectors
;
2729 int algorithm
= previous
? conf
->prev_algo
2733 sector_t chunk_number
;
2734 int dummy1
, dd_idx
= i
;
2736 struct stripe_head sh2
;
2738 chunk_offset
= sector_div(new_sector
, sectors_per_chunk
);
2739 stripe
= new_sector
;
2741 if (i
== sh
->pd_idx
)
2743 switch(conf
->level
) {
2746 switch (algorithm
) {
2747 case ALGORITHM_LEFT_ASYMMETRIC
:
2748 case ALGORITHM_RIGHT_ASYMMETRIC
:
2752 case ALGORITHM_LEFT_SYMMETRIC
:
2753 case ALGORITHM_RIGHT_SYMMETRIC
:
2756 i
-= (sh
->pd_idx
+ 1);
2758 case ALGORITHM_PARITY_0
:
2761 case ALGORITHM_PARITY_N
:
2768 if (i
== sh
->qd_idx
)
2769 return 0; /* It is the Q disk */
2770 switch (algorithm
) {
2771 case ALGORITHM_LEFT_ASYMMETRIC
:
2772 case ALGORITHM_RIGHT_ASYMMETRIC
:
2773 case ALGORITHM_ROTATING_ZERO_RESTART
:
2774 case ALGORITHM_ROTATING_N_RESTART
:
2775 if (sh
->pd_idx
== raid_disks
-1)
2776 i
--; /* Q D D D P */
2777 else if (i
> sh
->pd_idx
)
2778 i
-= 2; /* D D P Q D */
2780 case ALGORITHM_LEFT_SYMMETRIC
:
2781 case ALGORITHM_RIGHT_SYMMETRIC
:
2782 if (sh
->pd_idx
== raid_disks
-1)
2783 i
--; /* Q D D D P */
2788 i
-= (sh
->pd_idx
+ 2);
2791 case ALGORITHM_PARITY_0
:
2794 case ALGORITHM_PARITY_N
:
2796 case ALGORITHM_ROTATING_N_CONTINUE
:
2797 /* Like left_symmetric, but P is before Q */
2798 if (sh
->pd_idx
== 0)
2799 i
--; /* P D D D Q */
2804 i
-= (sh
->pd_idx
+ 1);
2807 case ALGORITHM_LEFT_ASYMMETRIC_6
:
2808 case ALGORITHM_RIGHT_ASYMMETRIC_6
:
2812 case ALGORITHM_LEFT_SYMMETRIC_6
:
2813 case ALGORITHM_RIGHT_SYMMETRIC_6
:
2815 i
+= data_disks
+ 1;
2816 i
-= (sh
->pd_idx
+ 1);
2818 case ALGORITHM_PARITY_0_6
:
2827 chunk_number
= stripe
* data_disks
+ i
;
2828 r_sector
= chunk_number
* sectors_per_chunk
+ chunk_offset
;
2830 check
= raid5_compute_sector(conf
, r_sector
,
2831 previous
, &dummy1
, &sh2
);
2832 if (check
!= sh
->sector
|| dummy1
!= dd_idx
|| sh2
.pd_idx
!= sh
->pd_idx
2833 || sh2
.qd_idx
!= sh
->qd_idx
) {
2834 printk(KERN_ERR
"md/raid:%s: compute_blocknr: map not correct\n",
2835 mdname(conf
->mddev
));
2842 schedule_reconstruction(struct stripe_head
*sh
, struct stripe_head_state
*s
,
2843 int rcw
, int expand
)
2845 int i
, pd_idx
= sh
->pd_idx
, qd_idx
= sh
->qd_idx
, disks
= sh
->disks
;
2846 struct r5conf
*conf
= sh
->raid_conf
;
2847 int level
= conf
->level
;
2851 for (i
= disks
; i
--; ) {
2852 struct r5dev
*dev
= &sh
->dev
[i
];
2855 set_bit(R5_LOCKED
, &dev
->flags
);
2856 set_bit(R5_Wantdrain
, &dev
->flags
);
2858 clear_bit(R5_UPTODATE
, &dev
->flags
);
2862 /* if we are not expanding this is a proper write request, and
2863 * there will be bios with new data to be drained into the
2868 /* False alarm, nothing to do */
2870 sh
->reconstruct_state
= reconstruct_state_drain_run
;
2871 set_bit(STRIPE_OP_BIODRAIN
, &s
->ops_request
);
2873 sh
->reconstruct_state
= reconstruct_state_run
;
2875 set_bit(STRIPE_OP_RECONSTRUCT
, &s
->ops_request
);
2877 if (s
->locked
+ conf
->max_degraded
== disks
)
2878 if (!test_and_set_bit(STRIPE_FULL_WRITE
, &sh
->state
))
2879 atomic_inc(&conf
->pending_full_writes
);
2881 BUG_ON(!(test_bit(R5_UPTODATE
, &sh
->dev
[pd_idx
].flags
) ||
2882 test_bit(R5_Wantcompute
, &sh
->dev
[pd_idx
].flags
)));
2883 BUG_ON(level
== 6 &&
2884 (!(test_bit(R5_UPTODATE
, &sh
->dev
[qd_idx
].flags
) ||
2885 test_bit(R5_Wantcompute
, &sh
->dev
[qd_idx
].flags
))));
2887 for (i
= disks
; i
--; ) {
2888 struct r5dev
*dev
= &sh
->dev
[i
];
2889 if (i
== pd_idx
|| i
== qd_idx
)
2893 (test_bit(R5_UPTODATE
, &dev
->flags
) ||
2894 test_bit(R5_Wantcompute
, &dev
->flags
))) {
2895 set_bit(R5_Wantdrain
, &dev
->flags
);
2896 set_bit(R5_LOCKED
, &dev
->flags
);
2897 clear_bit(R5_UPTODATE
, &dev
->flags
);
2902 /* False alarm - nothing to do */
2904 sh
->reconstruct_state
= reconstruct_state_prexor_drain_run
;
2905 set_bit(STRIPE_OP_PREXOR
, &s
->ops_request
);
2906 set_bit(STRIPE_OP_BIODRAIN
, &s
->ops_request
);
2907 set_bit(STRIPE_OP_RECONSTRUCT
, &s
->ops_request
);
2910 /* keep the parity disk(s) locked while asynchronous operations
2913 set_bit(R5_LOCKED
, &sh
->dev
[pd_idx
].flags
);
2914 clear_bit(R5_UPTODATE
, &sh
->dev
[pd_idx
].flags
);
2918 int qd_idx
= sh
->qd_idx
;
2919 struct r5dev
*dev
= &sh
->dev
[qd_idx
];
2921 set_bit(R5_LOCKED
, &dev
->flags
);
2922 clear_bit(R5_UPTODATE
, &dev
->flags
);
2926 pr_debug("%s: stripe %llu locked: %d ops_request: %lx\n",
2927 __func__
, (unsigned long long)sh
->sector
,
2928 s
->locked
, s
->ops_request
);
2932 * Each stripe/dev can have one or more bion attached.
2933 * toread/towrite point to the first in a chain.
2934 * The bi_next chain must be in order.
2936 static int add_stripe_bio(struct stripe_head
*sh
, struct bio
*bi
, int dd_idx
,
2937 int forwrite
, int previous
)
2940 struct r5conf
*conf
= sh
->raid_conf
;
2943 pr_debug("adding bi b#%llu to stripe s#%llu\n",
2944 (unsigned long long)bi
->bi_iter
.bi_sector
,
2945 (unsigned long long)sh
->sector
);
2948 * If several bio share a stripe. The bio bi_phys_segments acts as a
2949 * reference count to avoid race. The reference count should already be
2950 * increased before this function is called (for example, in
2951 * make_request()), so other bio sharing this stripe will not free the
2952 * stripe. If a stripe is owned by one stripe, the stripe lock will
2955 spin_lock_irq(&sh
->stripe_lock
);
2956 /* Don't allow new IO added to stripes in batch list */
2960 bip
= &sh
->dev
[dd_idx
].towrite
;
2964 bip
= &sh
->dev
[dd_idx
].toread
;
2965 while (*bip
&& (*bip
)->bi_iter
.bi_sector
< bi
->bi_iter
.bi_sector
) {
2966 if (bio_end_sector(*bip
) > bi
->bi_iter
.bi_sector
)
2968 bip
= & (*bip
)->bi_next
;
2970 if (*bip
&& (*bip
)->bi_iter
.bi_sector
< bio_end_sector(bi
))
2973 if (!forwrite
|| previous
)
2974 clear_bit(STRIPE_BATCH_READY
, &sh
->state
);
2976 BUG_ON(*bip
&& bi
->bi_next
&& (*bip
) != bi
->bi_next
);
2980 raid5_inc_bi_active_stripes(bi
);
2983 /* check if page is covered */
2984 sector_t sector
= sh
->dev
[dd_idx
].sector
;
2985 for (bi
=sh
->dev
[dd_idx
].towrite
;
2986 sector
< sh
->dev
[dd_idx
].sector
+ STRIPE_SECTORS
&&
2987 bi
&& bi
->bi_iter
.bi_sector
<= sector
;
2988 bi
= r5_next_bio(bi
, sh
->dev
[dd_idx
].sector
)) {
2989 if (bio_end_sector(bi
) >= sector
)
2990 sector
= bio_end_sector(bi
);
2992 if (sector
>= sh
->dev
[dd_idx
].sector
+ STRIPE_SECTORS
)
2993 if (!test_and_set_bit(R5_OVERWRITE
, &sh
->dev
[dd_idx
].flags
))
2994 sh
->overwrite_disks
++;
2997 pr_debug("added bi b#%llu to stripe s#%llu, disk %d.\n",
2998 (unsigned long long)(*bip
)->bi_iter
.bi_sector
,
2999 (unsigned long long)sh
->sector
, dd_idx
);
3001 if (conf
->mddev
->bitmap
&& firstwrite
) {
3002 /* Cannot hold spinlock over bitmap_startwrite,
3003 * but must ensure this isn't added to a batch until
3004 * we have added to the bitmap and set bm_seq.
3005 * So set STRIPE_BITMAP_PENDING to prevent
3007 * If multiple add_stripe_bio() calls race here they
3008 * much all set STRIPE_BITMAP_PENDING. So only the first one
3009 * to complete "bitmap_startwrite" gets to set
3010 * STRIPE_BIT_DELAY. This is important as once a stripe
3011 * is added to a batch, STRIPE_BIT_DELAY cannot be changed
3014 set_bit(STRIPE_BITMAP_PENDING
, &sh
->state
);
3015 spin_unlock_irq(&sh
->stripe_lock
);
3016 bitmap_startwrite(conf
->mddev
->bitmap
, sh
->sector
,
3018 spin_lock_irq(&sh
->stripe_lock
);
3019 clear_bit(STRIPE_BITMAP_PENDING
, &sh
->state
);
3020 if (!sh
->batch_head
) {
3021 sh
->bm_seq
= conf
->seq_flush
+1;
3022 set_bit(STRIPE_BIT_DELAY
, &sh
->state
);
3025 spin_unlock_irq(&sh
->stripe_lock
);
3027 if (stripe_can_batch(sh
))
3028 stripe_add_to_batch_list(conf
, sh
);
3032 set_bit(R5_Overlap
, &sh
->dev
[dd_idx
].flags
);
3033 spin_unlock_irq(&sh
->stripe_lock
);
3037 static void end_reshape(struct r5conf
*conf
);
3039 static void stripe_set_idx(sector_t stripe
, struct r5conf
*conf
, int previous
,
3040 struct stripe_head
*sh
)
3042 int sectors_per_chunk
=
3043 previous
? conf
->prev_chunk_sectors
: conf
->chunk_sectors
;
3045 int chunk_offset
= sector_div(stripe
, sectors_per_chunk
);
3046 int disks
= previous
? conf
->previous_raid_disks
: conf
->raid_disks
;
3048 raid5_compute_sector(conf
,
3049 stripe
* (disks
- conf
->max_degraded
)
3050 *sectors_per_chunk
+ chunk_offset
,
3056 handle_failed_stripe(struct r5conf
*conf
, struct stripe_head
*sh
,
3057 struct stripe_head_state
*s
, int disks
,
3058 struct bio
**return_bi
)
3061 BUG_ON(sh
->batch_head
);
3062 for (i
= disks
; i
--; ) {
3066 if (test_bit(R5_ReadError
, &sh
->dev
[i
].flags
)) {
3067 struct md_rdev
*rdev
;
3069 rdev
= rcu_dereference(conf
->disks
[i
].rdev
);
3070 if (rdev
&& test_bit(In_sync
, &rdev
->flags
))
3071 atomic_inc(&rdev
->nr_pending
);
3076 if (!rdev_set_badblocks(
3080 md_error(conf
->mddev
, rdev
);
3081 rdev_dec_pending(rdev
, conf
->mddev
);
3084 spin_lock_irq(&sh
->stripe_lock
);
3085 /* fail all writes first */
3086 bi
= sh
->dev
[i
].towrite
;
3087 sh
->dev
[i
].towrite
= NULL
;
3088 sh
->overwrite_disks
= 0;
3089 spin_unlock_irq(&sh
->stripe_lock
);
3093 if (test_and_clear_bit(R5_Overlap
, &sh
->dev
[i
].flags
))
3094 wake_up(&conf
->wait_for_overlap
);
3096 while (bi
&& bi
->bi_iter
.bi_sector
<
3097 sh
->dev
[i
].sector
+ STRIPE_SECTORS
) {
3098 struct bio
*nextbi
= r5_next_bio(bi
, sh
->dev
[i
].sector
);
3099 clear_bit(BIO_UPTODATE
, &bi
->bi_flags
);
3100 if (!raid5_dec_bi_active_stripes(bi
)) {
3101 md_write_end(conf
->mddev
);
3102 bi
->bi_next
= *return_bi
;
3108 bitmap_endwrite(conf
->mddev
->bitmap
, sh
->sector
,
3109 STRIPE_SECTORS
, 0, 0);
3111 /* and fail all 'written' */
3112 bi
= sh
->dev
[i
].written
;
3113 sh
->dev
[i
].written
= NULL
;
3114 if (test_and_clear_bit(R5_SkipCopy
, &sh
->dev
[i
].flags
)) {
3115 WARN_ON(test_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
));
3116 sh
->dev
[i
].page
= sh
->dev
[i
].orig_page
;
3119 if (bi
) bitmap_end
= 1;
3120 while (bi
&& bi
->bi_iter
.bi_sector
<
3121 sh
->dev
[i
].sector
+ STRIPE_SECTORS
) {
3122 struct bio
*bi2
= r5_next_bio(bi
, sh
->dev
[i
].sector
);
3123 clear_bit(BIO_UPTODATE
, &bi
->bi_flags
);
3124 if (!raid5_dec_bi_active_stripes(bi
)) {
3125 md_write_end(conf
->mddev
);
3126 bi
->bi_next
= *return_bi
;
3132 /* fail any reads if this device is non-operational and
3133 * the data has not reached the cache yet.
3135 if (!test_bit(R5_Wantfill
, &sh
->dev
[i
].flags
) &&
3136 (!test_bit(R5_Insync
, &sh
->dev
[i
].flags
) ||
3137 test_bit(R5_ReadError
, &sh
->dev
[i
].flags
))) {
3138 spin_lock_irq(&sh
->stripe_lock
);
3139 bi
= sh
->dev
[i
].toread
;
3140 sh
->dev
[i
].toread
= NULL
;
3141 spin_unlock_irq(&sh
->stripe_lock
);
3142 if (test_and_clear_bit(R5_Overlap
, &sh
->dev
[i
].flags
))
3143 wake_up(&conf
->wait_for_overlap
);
3144 while (bi
&& bi
->bi_iter
.bi_sector
<
3145 sh
->dev
[i
].sector
+ STRIPE_SECTORS
) {
3146 struct bio
*nextbi
=
3147 r5_next_bio(bi
, sh
->dev
[i
].sector
);
3148 clear_bit(BIO_UPTODATE
, &bi
->bi_flags
);
3149 if (!raid5_dec_bi_active_stripes(bi
)) {
3150 bi
->bi_next
= *return_bi
;
3157 bitmap_endwrite(conf
->mddev
->bitmap
, sh
->sector
,
3158 STRIPE_SECTORS
, 0, 0);
3159 /* If we were in the middle of a write the parity block might
3160 * still be locked - so just clear all R5_LOCKED flags
3162 clear_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
3165 if (test_and_clear_bit(STRIPE_FULL_WRITE
, &sh
->state
))
3166 if (atomic_dec_and_test(&conf
->pending_full_writes
))
3167 md_wakeup_thread(conf
->mddev
->thread
);
3171 handle_failed_sync(struct r5conf
*conf
, struct stripe_head
*sh
,
3172 struct stripe_head_state
*s
)
3177 BUG_ON(sh
->batch_head
);
3178 clear_bit(STRIPE_SYNCING
, &sh
->state
);
3179 if (test_and_clear_bit(R5_Overlap
, &sh
->dev
[sh
->pd_idx
].flags
))
3180 wake_up(&conf
->wait_for_overlap
);
3183 /* There is nothing more to do for sync/check/repair.
3184 * Don't even need to abort as that is handled elsewhere
3185 * if needed, and not always wanted e.g. if there is a known
3187 * For recover/replace we need to record a bad block on all
3188 * non-sync devices, or abort the recovery
3190 if (test_bit(MD_RECOVERY_RECOVER
, &conf
->mddev
->recovery
)) {
3191 /* During recovery devices cannot be removed, so
3192 * locking and refcounting of rdevs is not needed
3194 for (i
= 0; i
< conf
->raid_disks
; i
++) {
3195 struct md_rdev
*rdev
= conf
->disks
[i
].rdev
;
3197 && !test_bit(Faulty
, &rdev
->flags
)
3198 && !test_bit(In_sync
, &rdev
->flags
)
3199 && !rdev_set_badblocks(rdev
, sh
->sector
,
3202 rdev
= conf
->disks
[i
].replacement
;
3204 && !test_bit(Faulty
, &rdev
->flags
)
3205 && !test_bit(In_sync
, &rdev
->flags
)
3206 && !rdev_set_badblocks(rdev
, sh
->sector
,
3211 conf
->recovery_disabled
=
3212 conf
->mddev
->recovery_disabled
;
3214 md_done_sync(conf
->mddev
, STRIPE_SECTORS
, !abort
);
3217 static int want_replace(struct stripe_head
*sh
, int disk_idx
)
3219 struct md_rdev
*rdev
;
3221 /* Doing recovery so rcu locking not required */
3222 rdev
= sh
->raid_conf
->disks
[disk_idx
].replacement
;
3224 && !test_bit(Faulty
, &rdev
->flags
)
3225 && !test_bit(In_sync
, &rdev
->flags
)
3226 && (rdev
->recovery_offset
<= sh
->sector
3227 || rdev
->mddev
->recovery_cp
<= sh
->sector
))
3233 /* fetch_block - checks the given member device to see if its data needs
3234 * to be read or computed to satisfy a request.
3236 * Returns 1 when no more member devices need to be checked, otherwise returns
3237 * 0 to tell the loop in handle_stripe_fill to continue
3240 static int need_this_block(struct stripe_head
*sh
, struct stripe_head_state
*s
,
3241 int disk_idx
, int disks
)
3243 struct r5dev
*dev
= &sh
->dev
[disk_idx
];
3244 struct r5dev
*fdev
[2] = { &sh
->dev
[s
->failed_num
[0]],
3245 &sh
->dev
[s
->failed_num
[1]] };
3249 if (test_bit(R5_LOCKED
, &dev
->flags
) ||
3250 test_bit(R5_UPTODATE
, &dev
->flags
))
3251 /* No point reading this as we already have it or have
3252 * decided to get it.
3257 (dev
->towrite
&& !test_bit(R5_OVERWRITE
, &dev
->flags
)))
3258 /* We need this block to directly satisfy a request */
3261 if (s
->syncing
|| s
->expanding
||
3262 (s
->replacing
&& want_replace(sh
, disk_idx
)))
3263 /* When syncing, or expanding we read everything.
3264 * When replacing, we need the replaced block.
3268 if ((s
->failed
>= 1 && fdev
[0]->toread
) ||
3269 (s
->failed
>= 2 && fdev
[1]->toread
))
3270 /* If we want to read from a failed device, then
3271 * we need to actually read every other device.
3275 /* Sometimes neither read-modify-write nor reconstruct-write
3276 * cycles can work. In those cases we read every block we
3277 * can. Then the parity-update is certain to have enough to
3279 * This can only be a problem when we need to write something,
3280 * and some device has failed. If either of those tests
3281 * fail we need look no further.
3283 if (!s
->failed
|| !s
->to_write
)
3286 if (test_bit(R5_Insync
, &dev
->flags
) &&
3287 !test_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
3288 /* Pre-reads at not permitted until after short delay
3289 * to gather multiple requests. However if this
3290 * device is no Insync, the block could only be be computed
3291 * and there is no need to delay that.
3295 for (i
= 0; i
< s
->failed
; i
++) {
3296 if (fdev
[i
]->towrite
&&
3297 !test_bit(R5_UPTODATE
, &fdev
[i
]->flags
) &&
3298 !test_bit(R5_OVERWRITE
, &fdev
[i
]->flags
))
3299 /* If we have a partial write to a failed
3300 * device, then we will need to reconstruct
3301 * the content of that device, so all other
3302 * devices must be read.
3307 /* If we are forced to do a reconstruct-write, either because
3308 * the current RAID6 implementation only supports that, or
3309 * or because parity cannot be trusted and we are currently
3310 * recovering it, there is extra need to be careful.
3311 * If one of the devices that we would need to read, because
3312 * it is not being overwritten (and maybe not written at all)
3313 * is missing/faulty, then we need to read everything we can.
3315 if (sh
->raid_conf
->level
!= 6 &&
3316 sh
->sector
< sh
->raid_conf
->mddev
->recovery_cp
)
3317 /* reconstruct-write isn't being forced */
3319 for (i
= 0; i
< s
->failed
; i
++) {
3320 if (s
->failed_num
[i
] != sh
->pd_idx
&&
3321 s
->failed_num
[i
] != sh
->qd_idx
&&
3322 !test_bit(R5_UPTODATE
, &fdev
[i
]->flags
) &&
3323 !test_bit(R5_OVERWRITE
, &fdev
[i
]->flags
))
3330 static int fetch_block(struct stripe_head
*sh
, struct stripe_head_state
*s
,
3331 int disk_idx
, int disks
)
3333 struct r5dev
*dev
= &sh
->dev
[disk_idx
];
3335 /* is the data in this block needed, and can we get it? */
3336 if (need_this_block(sh
, s
, disk_idx
, disks
)) {
3337 /* we would like to get this block, possibly by computing it,
3338 * otherwise read it if the backing disk is insync
3340 BUG_ON(test_bit(R5_Wantcompute
, &dev
->flags
));
3341 BUG_ON(test_bit(R5_Wantread
, &dev
->flags
));
3342 BUG_ON(sh
->batch_head
);
3343 if ((s
->uptodate
== disks
- 1) &&
3344 (s
->failed
&& (disk_idx
== s
->failed_num
[0] ||
3345 disk_idx
== s
->failed_num
[1]))) {
3346 /* have disk failed, and we're requested to fetch it;
3349 pr_debug("Computing stripe %llu block %d\n",
3350 (unsigned long long)sh
->sector
, disk_idx
);
3351 set_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
3352 set_bit(STRIPE_OP_COMPUTE_BLK
, &s
->ops_request
);
3353 set_bit(R5_Wantcompute
, &dev
->flags
);
3354 sh
->ops
.target
= disk_idx
;
3355 sh
->ops
.target2
= -1; /* no 2nd target */
3357 /* Careful: from this point on 'uptodate' is in the eye
3358 * of raid_run_ops which services 'compute' operations
3359 * before writes. R5_Wantcompute flags a block that will
3360 * be R5_UPTODATE by the time it is needed for a
3361 * subsequent operation.
3365 } else if (s
->uptodate
== disks
-2 && s
->failed
>= 2) {
3366 /* Computing 2-failure is *very* expensive; only
3367 * do it if failed >= 2
3370 for (other
= disks
; other
--; ) {
3371 if (other
== disk_idx
)
3373 if (!test_bit(R5_UPTODATE
,
3374 &sh
->dev
[other
].flags
))
3378 pr_debug("Computing stripe %llu blocks %d,%d\n",
3379 (unsigned long long)sh
->sector
,
3381 set_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
3382 set_bit(STRIPE_OP_COMPUTE_BLK
, &s
->ops_request
);
3383 set_bit(R5_Wantcompute
, &sh
->dev
[disk_idx
].flags
);
3384 set_bit(R5_Wantcompute
, &sh
->dev
[other
].flags
);
3385 sh
->ops
.target
= disk_idx
;
3386 sh
->ops
.target2
= other
;
3390 } else if (test_bit(R5_Insync
, &dev
->flags
)) {
3391 set_bit(R5_LOCKED
, &dev
->flags
);
3392 set_bit(R5_Wantread
, &dev
->flags
);
3394 pr_debug("Reading block %d (sync=%d)\n",
3395 disk_idx
, s
->syncing
);
3403 * handle_stripe_fill - read or compute data to satisfy pending requests.
3405 static void handle_stripe_fill(struct stripe_head
*sh
,
3406 struct stripe_head_state
*s
,
3411 /* look for blocks to read/compute, skip this if a compute
3412 * is already in flight, or if the stripe contents are in the
3413 * midst of changing due to a write
3415 if (!test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
) && !sh
->check_state
&&
3416 !sh
->reconstruct_state
)
3417 for (i
= disks
; i
--; )
3418 if (fetch_block(sh
, s
, i
, disks
))
3420 set_bit(STRIPE_HANDLE
, &sh
->state
);
3423 static void break_stripe_batch_list(struct stripe_head
*head_sh
,
3424 unsigned long handle_flags
);
3425 /* handle_stripe_clean_event
3426 * any written block on an uptodate or failed drive can be returned.
3427 * Note that if we 'wrote' to a failed drive, it will be UPTODATE, but
3428 * never LOCKED, so we don't need to test 'failed' directly.
3430 static void handle_stripe_clean_event(struct r5conf
*conf
,
3431 struct stripe_head
*sh
, int disks
, struct bio
**return_bi
)
3435 int discard_pending
= 0;
3436 struct stripe_head
*head_sh
= sh
;
3437 bool do_endio
= false;
3439 for (i
= disks
; i
--; )
3440 if (sh
->dev
[i
].written
) {
3442 if (!test_bit(R5_LOCKED
, &dev
->flags
) &&
3443 (test_bit(R5_UPTODATE
, &dev
->flags
) ||
3444 test_bit(R5_Discard
, &dev
->flags
) ||
3445 test_bit(R5_SkipCopy
, &dev
->flags
))) {
3446 /* We can return any write requests */
3447 struct bio
*wbi
, *wbi2
;
3448 pr_debug("Return write for disc %d\n", i
);
3449 if (test_and_clear_bit(R5_Discard
, &dev
->flags
))
3450 clear_bit(R5_UPTODATE
, &dev
->flags
);
3451 if (test_and_clear_bit(R5_SkipCopy
, &dev
->flags
)) {
3452 WARN_ON(test_bit(R5_UPTODATE
, &dev
->flags
));
3457 dev
->page
= dev
->orig_page
;
3459 dev
->written
= NULL
;
3460 while (wbi
&& wbi
->bi_iter
.bi_sector
<
3461 dev
->sector
+ STRIPE_SECTORS
) {
3462 wbi2
= r5_next_bio(wbi
, dev
->sector
);
3463 if (!raid5_dec_bi_active_stripes(wbi
)) {
3464 md_write_end(conf
->mddev
);
3465 wbi
->bi_next
= *return_bi
;
3470 bitmap_endwrite(conf
->mddev
->bitmap
, sh
->sector
,
3472 !test_bit(STRIPE_DEGRADED
, &sh
->state
),
3474 if (head_sh
->batch_head
) {
3475 sh
= list_first_entry(&sh
->batch_list
,
3478 if (sh
!= head_sh
) {
3485 } else if (test_bit(R5_Discard
, &dev
->flags
))
3486 discard_pending
= 1;
3487 WARN_ON(test_bit(R5_SkipCopy
, &dev
->flags
));
3488 WARN_ON(dev
->page
!= dev
->orig_page
);
3490 if (!discard_pending
&&
3491 test_bit(R5_Discard
, &sh
->dev
[sh
->pd_idx
].flags
)) {
3492 clear_bit(R5_Discard
, &sh
->dev
[sh
->pd_idx
].flags
);
3493 clear_bit(R5_UPTODATE
, &sh
->dev
[sh
->pd_idx
].flags
);
3494 if (sh
->qd_idx
>= 0) {
3495 clear_bit(R5_Discard
, &sh
->dev
[sh
->qd_idx
].flags
);
3496 clear_bit(R5_UPTODATE
, &sh
->dev
[sh
->qd_idx
].flags
);
3498 /* now that discard is done we can proceed with any sync */
3499 clear_bit(STRIPE_DISCARD
, &sh
->state
);
3501 * SCSI discard will change some bio fields and the stripe has
3502 * no updated data, so remove it from hash list and the stripe
3503 * will be reinitialized
3505 spin_lock_irq(&conf
->device_lock
);
3508 if (head_sh
->batch_head
) {
3509 sh
= list_first_entry(&sh
->batch_list
,
3510 struct stripe_head
, batch_list
);
3514 spin_unlock_irq(&conf
->device_lock
);
3517 if (test_bit(STRIPE_SYNC_REQUESTED
, &sh
->state
))
3518 set_bit(STRIPE_HANDLE
, &sh
->state
);
3522 if (test_and_clear_bit(STRIPE_FULL_WRITE
, &sh
->state
))
3523 if (atomic_dec_and_test(&conf
->pending_full_writes
))
3524 md_wakeup_thread(conf
->mddev
->thread
);
3526 if (head_sh
->batch_head
&& do_endio
)
3527 break_stripe_batch_list(head_sh
, STRIPE_EXPAND_SYNC_FLAGS
);
3530 static void handle_stripe_dirtying(struct r5conf
*conf
,
3531 struct stripe_head
*sh
,
3532 struct stripe_head_state
*s
,
3535 int rmw
= 0, rcw
= 0, i
;
3536 sector_t recovery_cp
= conf
->mddev
->recovery_cp
;
3538 /* Check whether resync is now happening or should start.
3539 * If yes, then the array is dirty (after unclean shutdown or
3540 * initial creation), so parity in some stripes might be inconsistent.
3541 * In this case, we need to always do reconstruct-write, to ensure
3542 * that in case of drive failure or read-error correction, we
3543 * generate correct data from the parity.
3545 if (conf
->rmw_level
== PARITY_DISABLE_RMW
||
3546 (recovery_cp
< MaxSector
&& sh
->sector
>= recovery_cp
&&
3548 /* Calculate the real rcw later - for now make it
3549 * look like rcw is cheaper
3552 pr_debug("force RCW rmw_level=%u, recovery_cp=%llu sh->sector=%llu\n",
3553 conf
->rmw_level
, (unsigned long long)recovery_cp
,
3554 (unsigned long long)sh
->sector
);
3555 } else for (i
= disks
; i
--; ) {
3556 /* would I have to read this buffer for read_modify_write */
3557 struct r5dev
*dev
= &sh
->dev
[i
];
3558 if ((dev
->towrite
|| i
== sh
->pd_idx
|| i
== sh
->qd_idx
) &&
3559 !test_bit(R5_LOCKED
, &dev
->flags
) &&
3560 !(test_bit(R5_UPTODATE
, &dev
->flags
) ||
3561 test_bit(R5_Wantcompute
, &dev
->flags
))) {
3562 if (test_bit(R5_Insync
, &dev
->flags
))
3565 rmw
+= 2*disks
; /* cannot read it */
3567 /* Would I have to read this buffer for reconstruct_write */
3568 if (!test_bit(R5_OVERWRITE
, &dev
->flags
) &&
3569 i
!= sh
->pd_idx
&& i
!= sh
->qd_idx
&&
3570 !test_bit(R5_LOCKED
, &dev
->flags
) &&
3571 !(test_bit(R5_UPTODATE
, &dev
->flags
) ||
3572 test_bit(R5_Wantcompute
, &dev
->flags
))) {
3573 if (test_bit(R5_Insync
, &dev
->flags
))
3579 pr_debug("for sector %llu, rmw=%d rcw=%d\n",
3580 (unsigned long long)sh
->sector
, rmw
, rcw
);
3581 set_bit(STRIPE_HANDLE
, &sh
->state
);
3582 if ((rmw
< rcw
|| (rmw
== rcw
&& conf
->rmw_level
== PARITY_ENABLE_RMW
)) && rmw
> 0) {
3583 /* prefer read-modify-write, but need to get some data */
3584 if (conf
->mddev
->queue
)
3585 blk_add_trace_msg(conf
->mddev
->queue
,
3586 "raid5 rmw %llu %d",
3587 (unsigned long long)sh
->sector
, rmw
);
3588 for (i
= disks
; i
--; ) {
3589 struct r5dev
*dev
= &sh
->dev
[i
];
3590 if ((dev
->towrite
|| i
== sh
->pd_idx
|| i
== sh
->qd_idx
) &&
3591 !test_bit(R5_LOCKED
, &dev
->flags
) &&
3592 !(test_bit(R5_UPTODATE
, &dev
->flags
) ||
3593 test_bit(R5_Wantcompute
, &dev
->flags
)) &&
3594 test_bit(R5_Insync
, &dev
->flags
)) {
3595 if (test_bit(STRIPE_PREREAD_ACTIVE
,
3597 pr_debug("Read_old block %d for r-m-w\n",
3599 set_bit(R5_LOCKED
, &dev
->flags
);
3600 set_bit(R5_Wantread
, &dev
->flags
);
3603 set_bit(STRIPE_DELAYED
, &sh
->state
);
3604 set_bit(STRIPE_HANDLE
, &sh
->state
);
3609 if ((rcw
< rmw
|| (rcw
== rmw
&& conf
->rmw_level
!= PARITY_ENABLE_RMW
)) && rcw
> 0) {
3610 /* want reconstruct write, but need to get some data */
3613 for (i
= disks
; i
--; ) {
3614 struct r5dev
*dev
= &sh
->dev
[i
];
3615 if (!test_bit(R5_OVERWRITE
, &dev
->flags
) &&
3616 i
!= sh
->pd_idx
&& i
!= sh
->qd_idx
&&
3617 !test_bit(R5_LOCKED
, &dev
->flags
) &&
3618 !(test_bit(R5_UPTODATE
, &dev
->flags
) ||
3619 test_bit(R5_Wantcompute
, &dev
->flags
))) {
3621 if (test_bit(R5_Insync
, &dev
->flags
) &&
3622 test_bit(STRIPE_PREREAD_ACTIVE
,
3624 pr_debug("Read_old block "
3625 "%d for Reconstruct\n", i
);
3626 set_bit(R5_LOCKED
, &dev
->flags
);
3627 set_bit(R5_Wantread
, &dev
->flags
);
3631 set_bit(STRIPE_DELAYED
, &sh
->state
);
3632 set_bit(STRIPE_HANDLE
, &sh
->state
);
3636 if (rcw
&& conf
->mddev
->queue
)
3637 blk_add_trace_msg(conf
->mddev
->queue
, "raid5 rcw %llu %d %d %d",
3638 (unsigned long long)sh
->sector
,
3639 rcw
, qread
, test_bit(STRIPE_DELAYED
, &sh
->state
));
3642 if (rcw
> disks
&& rmw
> disks
&&
3643 !test_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
3644 set_bit(STRIPE_DELAYED
, &sh
->state
);
3646 /* now if nothing is locked, and if we have enough data,
3647 * we can start a write request
3649 /* since handle_stripe can be called at any time we need to handle the
3650 * case where a compute block operation has been submitted and then a
3651 * subsequent call wants to start a write request. raid_run_ops only
3652 * handles the case where compute block and reconstruct are requested
3653 * simultaneously. If this is not the case then new writes need to be
3654 * held off until the compute completes.
3656 if ((s
->req_compute
|| !test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
)) &&
3657 (s
->locked
== 0 && (rcw
== 0 || rmw
== 0) &&
3658 !test_bit(STRIPE_BIT_DELAY
, &sh
->state
)))
3659 schedule_reconstruction(sh
, s
, rcw
== 0, 0);
3662 static void handle_parity_checks5(struct r5conf
*conf
, struct stripe_head
*sh
,
3663 struct stripe_head_state
*s
, int disks
)
3665 struct r5dev
*dev
= NULL
;
3667 BUG_ON(sh
->batch_head
);
3668 set_bit(STRIPE_HANDLE
, &sh
->state
);
3670 switch (sh
->check_state
) {
3671 case check_state_idle
:
3672 /* start a new check operation if there are no failures */
3673 if (s
->failed
== 0) {
3674 BUG_ON(s
->uptodate
!= disks
);
3675 sh
->check_state
= check_state_run
;
3676 set_bit(STRIPE_OP_CHECK
, &s
->ops_request
);
3677 clear_bit(R5_UPTODATE
, &sh
->dev
[sh
->pd_idx
].flags
);
3681 dev
= &sh
->dev
[s
->failed_num
[0]];
3683 case check_state_compute_result
:
3684 sh
->check_state
= check_state_idle
;
3686 dev
= &sh
->dev
[sh
->pd_idx
];
3688 /* check that a write has not made the stripe insync */
3689 if (test_bit(STRIPE_INSYNC
, &sh
->state
))
3692 /* either failed parity check, or recovery is happening */
3693 BUG_ON(!test_bit(R5_UPTODATE
, &dev
->flags
));
3694 BUG_ON(s
->uptodate
!= disks
);
3696 set_bit(R5_LOCKED
, &dev
->flags
);
3698 set_bit(R5_Wantwrite
, &dev
->flags
);
3700 clear_bit(STRIPE_DEGRADED
, &sh
->state
);
3701 set_bit(STRIPE_INSYNC
, &sh
->state
);
3703 case check_state_run
:
3704 break; /* we will be called again upon completion */
3705 case check_state_check_result
:
3706 sh
->check_state
= check_state_idle
;
3708 /* if a failure occurred during the check operation, leave
3709 * STRIPE_INSYNC not set and let the stripe be handled again
3714 /* handle a successful check operation, if parity is correct
3715 * we are done. Otherwise update the mismatch count and repair
3716 * parity if !MD_RECOVERY_CHECK
3718 if ((sh
->ops
.zero_sum_result
& SUM_CHECK_P_RESULT
) == 0)
3719 /* parity is correct (on disc,
3720 * not in buffer any more)
3722 set_bit(STRIPE_INSYNC
, &sh
->state
);
3724 atomic64_add(STRIPE_SECTORS
, &conf
->mddev
->resync_mismatches
);
3725 if (test_bit(MD_RECOVERY_CHECK
, &conf
->mddev
->recovery
))
3726 /* don't try to repair!! */
3727 set_bit(STRIPE_INSYNC
, &sh
->state
);
3729 sh
->check_state
= check_state_compute_run
;
3730 set_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
3731 set_bit(STRIPE_OP_COMPUTE_BLK
, &s
->ops_request
);
3732 set_bit(R5_Wantcompute
,
3733 &sh
->dev
[sh
->pd_idx
].flags
);
3734 sh
->ops
.target
= sh
->pd_idx
;
3735 sh
->ops
.target2
= -1;
3740 case check_state_compute_run
:
3743 printk(KERN_ERR
"%s: unknown check_state: %d sector: %llu\n",
3744 __func__
, sh
->check_state
,
3745 (unsigned long long) sh
->sector
);
3750 static void handle_parity_checks6(struct r5conf
*conf
, struct stripe_head
*sh
,
3751 struct stripe_head_state
*s
,
3754 int pd_idx
= sh
->pd_idx
;
3755 int qd_idx
= sh
->qd_idx
;
3758 BUG_ON(sh
->batch_head
);
3759 set_bit(STRIPE_HANDLE
, &sh
->state
);
3761 BUG_ON(s
->failed
> 2);
3763 /* Want to check and possibly repair P and Q.
3764 * However there could be one 'failed' device, in which
3765 * case we can only check one of them, possibly using the
3766 * other to generate missing data
3769 switch (sh
->check_state
) {
3770 case check_state_idle
:
3771 /* start a new check operation if there are < 2 failures */
3772 if (s
->failed
== s
->q_failed
) {
3773 /* The only possible failed device holds Q, so it
3774 * makes sense to check P (If anything else were failed,
3775 * we would have used P to recreate it).
3777 sh
->check_state
= check_state_run
;
3779 if (!s
->q_failed
&& s
->failed
< 2) {
3780 /* Q is not failed, and we didn't use it to generate
3781 * anything, so it makes sense to check it
3783 if (sh
->check_state
== check_state_run
)
3784 sh
->check_state
= check_state_run_pq
;
3786 sh
->check_state
= check_state_run_q
;
3789 /* discard potentially stale zero_sum_result */
3790 sh
->ops
.zero_sum_result
= 0;
3792 if (sh
->check_state
== check_state_run
) {
3793 /* async_xor_zero_sum destroys the contents of P */
3794 clear_bit(R5_UPTODATE
, &sh
->dev
[pd_idx
].flags
);
3797 if (sh
->check_state
>= check_state_run
&&
3798 sh
->check_state
<= check_state_run_pq
) {
3799 /* async_syndrome_zero_sum preserves P and Q, so
3800 * no need to mark them !uptodate here
3802 set_bit(STRIPE_OP_CHECK
, &s
->ops_request
);
3806 /* we have 2-disk failure */
3807 BUG_ON(s
->failed
!= 2);
3809 case check_state_compute_result
:
3810 sh
->check_state
= check_state_idle
;
3812 /* check that a write has not made the stripe insync */
3813 if (test_bit(STRIPE_INSYNC
, &sh
->state
))
3816 /* now write out any block on a failed drive,
3817 * or P or Q if they were recomputed
3819 BUG_ON(s
->uptodate
< disks
- 1); /* We don't need Q to recover */
3820 if (s
->failed
== 2) {
3821 dev
= &sh
->dev
[s
->failed_num
[1]];
3823 set_bit(R5_LOCKED
, &dev
->flags
);
3824 set_bit(R5_Wantwrite
, &dev
->flags
);
3826 if (s
->failed
>= 1) {
3827 dev
= &sh
->dev
[s
->failed_num
[0]];
3829 set_bit(R5_LOCKED
, &dev
->flags
);
3830 set_bit(R5_Wantwrite
, &dev
->flags
);
3832 if (sh
->ops
.zero_sum_result
& SUM_CHECK_P_RESULT
) {
3833 dev
= &sh
->dev
[pd_idx
];
3835 set_bit(R5_LOCKED
, &dev
->flags
);
3836 set_bit(R5_Wantwrite
, &dev
->flags
);
3838 if (sh
->ops
.zero_sum_result
& SUM_CHECK_Q_RESULT
) {
3839 dev
= &sh
->dev
[qd_idx
];
3841 set_bit(R5_LOCKED
, &dev
->flags
);
3842 set_bit(R5_Wantwrite
, &dev
->flags
);
3844 clear_bit(STRIPE_DEGRADED
, &sh
->state
);
3846 set_bit(STRIPE_INSYNC
, &sh
->state
);
3848 case check_state_run
:
3849 case check_state_run_q
:
3850 case check_state_run_pq
:
3851 break; /* we will be called again upon completion */
3852 case check_state_check_result
:
3853 sh
->check_state
= check_state_idle
;
3855 /* handle a successful check operation, if parity is correct
3856 * we are done. Otherwise update the mismatch count and repair
3857 * parity if !MD_RECOVERY_CHECK
3859 if (sh
->ops
.zero_sum_result
== 0) {
3860 /* both parities are correct */
3862 set_bit(STRIPE_INSYNC
, &sh
->state
);
3864 /* in contrast to the raid5 case we can validate
3865 * parity, but still have a failure to write
3868 sh
->check_state
= check_state_compute_result
;
3869 /* Returning at this point means that we may go
3870 * off and bring p and/or q uptodate again so
3871 * we make sure to check zero_sum_result again
3872 * to verify if p or q need writeback
3876 atomic64_add(STRIPE_SECTORS
, &conf
->mddev
->resync_mismatches
);
3877 if (test_bit(MD_RECOVERY_CHECK
, &conf
->mddev
->recovery
))
3878 /* don't try to repair!! */
3879 set_bit(STRIPE_INSYNC
, &sh
->state
);
3881 int *target
= &sh
->ops
.target
;
3883 sh
->ops
.target
= -1;
3884 sh
->ops
.target2
= -1;
3885 sh
->check_state
= check_state_compute_run
;
3886 set_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
3887 set_bit(STRIPE_OP_COMPUTE_BLK
, &s
->ops_request
);
3888 if (sh
->ops
.zero_sum_result
& SUM_CHECK_P_RESULT
) {
3889 set_bit(R5_Wantcompute
,
3890 &sh
->dev
[pd_idx
].flags
);
3892 target
= &sh
->ops
.target2
;
3895 if (sh
->ops
.zero_sum_result
& SUM_CHECK_Q_RESULT
) {
3896 set_bit(R5_Wantcompute
,
3897 &sh
->dev
[qd_idx
].flags
);
3904 case check_state_compute_run
:
3907 printk(KERN_ERR
"%s: unknown check_state: %d sector: %llu\n",
3908 __func__
, sh
->check_state
,
3909 (unsigned long long) sh
->sector
);
3914 static void handle_stripe_expansion(struct r5conf
*conf
, struct stripe_head
*sh
)
3918 /* We have read all the blocks in this stripe and now we need to
3919 * copy some of them into a target stripe for expand.
3921 struct dma_async_tx_descriptor
*tx
= NULL
;
3922 BUG_ON(sh
->batch_head
);
3923 clear_bit(STRIPE_EXPAND_SOURCE
, &sh
->state
);
3924 for (i
= 0; i
< sh
->disks
; i
++)
3925 if (i
!= sh
->pd_idx
&& i
!= sh
->qd_idx
) {
3927 struct stripe_head
*sh2
;
3928 struct async_submit_ctl submit
;
3930 sector_t bn
= compute_blocknr(sh
, i
, 1);
3931 sector_t s
= raid5_compute_sector(conf
, bn
, 0,
3933 sh2
= get_active_stripe(conf
, s
, 0, 1, 1);
3935 /* so far only the early blocks of this stripe
3936 * have been requested. When later blocks
3937 * get requested, we will try again
3940 if (!test_bit(STRIPE_EXPANDING
, &sh2
->state
) ||
3941 test_bit(R5_Expanded
, &sh2
->dev
[dd_idx
].flags
)) {
3942 /* must have already done this block */
3943 release_stripe(sh2
);
3947 /* place all the copies on one channel */
3948 init_async_submit(&submit
, 0, tx
, NULL
, NULL
, NULL
);
3949 tx
= async_memcpy(sh2
->dev
[dd_idx
].page
,
3950 sh
->dev
[i
].page
, 0, 0, STRIPE_SIZE
,
3953 set_bit(R5_Expanded
, &sh2
->dev
[dd_idx
].flags
);
3954 set_bit(R5_UPTODATE
, &sh2
->dev
[dd_idx
].flags
);
3955 for (j
= 0; j
< conf
->raid_disks
; j
++)
3956 if (j
!= sh2
->pd_idx
&&
3958 !test_bit(R5_Expanded
, &sh2
->dev
[j
].flags
))
3960 if (j
== conf
->raid_disks
) {
3961 set_bit(STRIPE_EXPAND_READY
, &sh2
->state
);
3962 set_bit(STRIPE_HANDLE
, &sh2
->state
);
3964 release_stripe(sh2
);
3967 /* done submitting copies, wait for them to complete */
3968 async_tx_quiesce(&tx
);
3972 * handle_stripe - do things to a stripe.
3974 * We lock the stripe by setting STRIPE_ACTIVE and then examine the
3975 * state of various bits to see what needs to be done.
3977 * return some read requests which now have data
3978 * return some write requests which are safely on storage
3979 * schedule a read on some buffers
3980 * schedule a write of some buffers
3981 * return confirmation of parity correctness
3985 static void analyse_stripe(struct stripe_head
*sh
, struct stripe_head_state
*s
)
3987 struct r5conf
*conf
= sh
->raid_conf
;
3988 int disks
= sh
->disks
;
3991 int do_recovery
= 0;
3993 memset(s
, 0, sizeof(*s
));
3995 s
->expanding
= test_bit(STRIPE_EXPAND_SOURCE
, &sh
->state
) && !sh
->batch_head
;
3996 s
->expanded
= test_bit(STRIPE_EXPAND_READY
, &sh
->state
) && !sh
->batch_head
;
3997 s
->failed_num
[0] = -1;
3998 s
->failed_num
[1] = -1;
4000 /* Now to look around and see what can be done */
4002 for (i
=disks
; i
--; ) {
4003 struct md_rdev
*rdev
;
4010 pr_debug("check %d: state 0x%lx read %p write %p written %p\n",
4012 dev
->toread
, dev
->towrite
, dev
->written
);
4013 /* maybe we can reply to a read
4015 * new wantfill requests are only permitted while
4016 * ops_complete_biofill is guaranteed to be inactive
4018 if (test_bit(R5_UPTODATE
, &dev
->flags
) && dev
->toread
&&
4019 !test_bit(STRIPE_BIOFILL_RUN
, &sh
->state
))
4020 set_bit(R5_Wantfill
, &dev
->flags
);
4022 /* now count some things */
4023 if (test_bit(R5_LOCKED
, &dev
->flags
))
4025 if (test_bit(R5_UPTODATE
, &dev
->flags
))
4027 if (test_bit(R5_Wantcompute
, &dev
->flags
)) {
4029 BUG_ON(s
->compute
> 2);
4032 if (test_bit(R5_Wantfill
, &dev
->flags
))
4034 else if (dev
->toread
)
4038 if (!test_bit(R5_OVERWRITE
, &dev
->flags
))
4043 /* Prefer to use the replacement for reads, but only
4044 * if it is recovered enough and has no bad blocks.
4046 rdev
= rcu_dereference(conf
->disks
[i
].replacement
);
4047 if (rdev
&& !test_bit(Faulty
, &rdev
->flags
) &&
4048 rdev
->recovery_offset
>= sh
->sector
+ STRIPE_SECTORS
&&
4049 !is_badblock(rdev
, sh
->sector
, STRIPE_SECTORS
,
4050 &first_bad
, &bad_sectors
))
4051 set_bit(R5_ReadRepl
, &dev
->flags
);
4054 set_bit(R5_NeedReplace
, &dev
->flags
);
4055 rdev
= rcu_dereference(conf
->disks
[i
].rdev
);
4056 clear_bit(R5_ReadRepl
, &dev
->flags
);
4058 if (rdev
&& test_bit(Faulty
, &rdev
->flags
))
4061 is_bad
= is_badblock(rdev
, sh
->sector
, STRIPE_SECTORS
,
4062 &first_bad
, &bad_sectors
);
4063 if (s
->blocked_rdev
== NULL
4064 && (test_bit(Blocked
, &rdev
->flags
)
4067 set_bit(BlockedBadBlocks
,
4069 s
->blocked_rdev
= rdev
;
4070 atomic_inc(&rdev
->nr_pending
);
4073 clear_bit(R5_Insync
, &dev
->flags
);
4077 /* also not in-sync */
4078 if (!test_bit(WriteErrorSeen
, &rdev
->flags
) &&
4079 test_bit(R5_UPTODATE
, &dev
->flags
)) {
4080 /* treat as in-sync, but with a read error
4081 * which we can now try to correct
4083 set_bit(R5_Insync
, &dev
->flags
);
4084 set_bit(R5_ReadError
, &dev
->flags
);
4086 } else if (test_bit(In_sync
, &rdev
->flags
))
4087 set_bit(R5_Insync
, &dev
->flags
);
4088 else if (sh
->sector
+ STRIPE_SECTORS
<= rdev
->recovery_offset
)
4089 /* in sync if before recovery_offset */
4090 set_bit(R5_Insync
, &dev
->flags
);
4091 else if (test_bit(R5_UPTODATE
, &dev
->flags
) &&
4092 test_bit(R5_Expanded
, &dev
->flags
))
4093 /* If we've reshaped into here, we assume it is Insync.
4094 * We will shortly update recovery_offset to make
4097 set_bit(R5_Insync
, &dev
->flags
);
4099 if (test_bit(R5_WriteError
, &dev
->flags
)) {
4100 /* This flag does not apply to '.replacement'
4101 * only to .rdev, so make sure to check that*/
4102 struct md_rdev
*rdev2
= rcu_dereference(
4103 conf
->disks
[i
].rdev
);
4105 clear_bit(R5_Insync
, &dev
->flags
);
4106 if (rdev2
&& !test_bit(Faulty
, &rdev2
->flags
)) {
4107 s
->handle_bad_blocks
= 1;
4108 atomic_inc(&rdev2
->nr_pending
);
4110 clear_bit(R5_WriteError
, &dev
->flags
);
4112 if (test_bit(R5_MadeGood
, &dev
->flags
)) {
4113 /* This flag does not apply to '.replacement'
4114 * only to .rdev, so make sure to check that*/
4115 struct md_rdev
*rdev2
= rcu_dereference(
4116 conf
->disks
[i
].rdev
);
4117 if (rdev2
&& !test_bit(Faulty
, &rdev2
->flags
)) {
4118 s
->handle_bad_blocks
= 1;
4119 atomic_inc(&rdev2
->nr_pending
);
4121 clear_bit(R5_MadeGood
, &dev
->flags
);
4123 if (test_bit(R5_MadeGoodRepl
, &dev
->flags
)) {
4124 struct md_rdev
*rdev2
= rcu_dereference(
4125 conf
->disks
[i
].replacement
);
4126 if (rdev2
&& !test_bit(Faulty
, &rdev2
->flags
)) {
4127 s
->handle_bad_blocks
= 1;
4128 atomic_inc(&rdev2
->nr_pending
);
4130 clear_bit(R5_MadeGoodRepl
, &dev
->flags
);
4132 if (!test_bit(R5_Insync
, &dev
->flags
)) {
4133 /* The ReadError flag will just be confusing now */
4134 clear_bit(R5_ReadError
, &dev
->flags
);
4135 clear_bit(R5_ReWrite
, &dev
->flags
);
4137 if (test_bit(R5_ReadError
, &dev
->flags
))
4138 clear_bit(R5_Insync
, &dev
->flags
);
4139 if (!test_bit(R5_Insync
, &dev
->flags
)) {
4141 s
->failed_num
[s
->failed
] = i
;
4143 if (rdev
&& !test_bit(Faulty
, &rdev
->flags
))
4147 if (test_bit(STRIPE_SYNCING
, &sh
->state
)) {
4148 /* If there is a failed device being replaced,
4149 * we must be recovering.
4150 * else if we are after recovery_cp, we must be syncing
4151 * else if MD_RECOVERY_REQUESTED is set, we also are syncing.
4152 * else we can only be replacing
4153 * sync and recovery both need to read all devices, and so
4154 * use the same flag.
4157 sh
->sector
>= conf
->mddev
->recovery_cp
||
4158 test_bit(MD_RECOVERY_REQUESTED
, &(conf
->mddev
->recovery
)))
4166 static int clear_batch_ready(struct stripe_head
*sh
)
4168 /* Return '1' if this is a member of batch, or
4169 * '0' if it is a lone stripe or a head which can now be
4172 struct stripe_head
*tmp
;
4173 if (!test_and_clear_bit(STRIPE_BATCH_READY
, &sh
->state
))
4174 return (sh
->batch_head
&& sh
->batch_head
!= sh
);
4175 spin_lock(&sh
->stripe_lock
);
4176 if (!sh
->batch_head
) {
4177 spin_unlock(&sh
->stripe_lock
);
4182 * this stripe could be added to a batch list before we check
4183 * BATCH_READY, skips it
4185 if (sh
->batch_head
!= sh
) {
4186 spin_unlock(&sh
->stripe_lock
);
4189 spin_lock(&sh
->batch_lock
);
4190 list_for_each_entry(tmp
, &sh
->batch_list
, batch_list
)
4191 clear_bit(STRIPE_BATCH_READY
, &tmp
->state
);
4192 spin_unlock(&sh
->batch_lock
);
4193 spin_unlock(&sh
->stripe_lock
);
4196 * BATCH_READY is cleared, no new stripes can be added.
4197 * batch_list can be accessed without lock
4202 static void break_stripe_batch_list(struct stripe_head
*head_sh
,
4203 unsigned long handle_flags
)
4205 struct stripe_head
*sh
, *next
;
4209 list_for_each_entry_safe(sh
, next
, &head_sh
->batch_list
, batch_list
) {
4211 list_del_init(&sh
->batch_list
);
4213 WARN_ON_ONCE(sh
->state
& ((1 << STRIPE_ACTIVE
) |
4214 (1 << STRIPE_SYNCING
) |
4215 (1 << STRIPE_REPLACED
) |
4216 (1 << STRIPE_PREREAD_ACTIVE
) |
4217 (1 << STRIPE_DELAYED
) |
4218 (1 << STRIPE_BIT_DELAY
) |
4219 (1 << STRIPE_FULL_WRITE
) |
4220 (1 << STRIPE_BIOFILL_RUN
) |
4221 (1 << STRIPE_COMPUTE_RUN
) |
4222 (1 << STRIPE_OPS_REQ_PENDING
) |
4223 (1 << STRIPE_DISCARD
) |
4224 (1 << STRIPE_BATCH_READY
) |
4225 (1 << STRIPE_BATCH_ERR
) |
4226 (1 << STRIPE_BITMAP_PENDING
)));
4227 WARN_ON_ONCE(head_sh
->state
& ((1 << STRIPE_DISCARD
) |
4228 (1 << STRIPE_REPLACED
)));
4230 set_mask_bits(&sh
->state
, ~(STRIPE_EXPAND_SYNC_FLAGS
|
4231 (1 << STRIPE_DEGRADED
)),
4232 head_sh
->state
& (1 << STRIPE_INSYNC
));
4234 sh
->check_state
= head_sh
->check_state
;
4235 sh
->reconstruct_state
= head_sh
->reconstruct_state
;
4236 for (i
= 0; i
< sh
->disks
; i
++) {
4237 if (test_and_clear_bit(R5_Overlap
, &sh
->dev
[i
].flags
))
4239 sh
->dev
[i
].flags
= head_sh
->dev
[i
].flags
&
4240 (~((1 << R5_WriteError
) | (1 << R5_Overlap
)));
4242 spin_lock_irq(&sh
->stripe_lock
);
4243 sh
->batch_head
= NULL
;
4244 spin_unlock_irq(&sh
->stripe_lock
);
4245 if (handle_flags
== 0 ||
4246 sh
->state
& handle_flags
)
4247 set_bit(STRIPE_HANDLE
, &sh
->state
);
4250 spin_lock_irq(&head_sh
->stripe_lock
);
4251 head_sh
->batch_head
= NULL
;
4252 spin_unlock_irq(&head_sh
->stripe_lock
);
4253 for (i
= 0; i
< head_sh
->disks
; i
++)
4254 if (test_and_clear_bit(R5_Overlap
, &head_sh
->dev
[i
].flags
))
4256 if (head_sh
->state
& handle_flags
)
4257 set_bit(STRIPE_HANDLE
, &head_sh
->state
);
4260 wake_up(&head_sh
->raid_conf
->wait_for_overlap
);
4263 static void handle_stripe(struct stripe_head
*sh
)
4265 struct stripe_head_state s
;
4266 struct r5conf
*conf
= sh
->raid_conf
;
4269 int disks
= sh
->disks
;
4270 struct r5dev
*pdev
, *qdev
;
4272 clear_bit(STRIPE_HANDLE
, &sh
->state
);
4273 if (test_and_set_bit_lock(STRIPE_ACTIVE
, &sh
->state
)) {
4274 /* already being handled, ensure it gets handled
4275 * again when current action finishes */
4276 set_bit(STRIPE_HANDLE
, &sh
->state
);
4280 if (clear_batch_ready(sh
) ) {
4281 clear_bit_unlock(STRIPE_ACTIVE
, &sh
->state
);
4285 if (test_and_clear_bit(STRIPE_BATCH_ERR
, &sh
->state
))
4286 break_stripe_batch_list(sh
, 0);
4288 if (test_bit(STRIPE_SYNC_REQUESTED
, &sh
->state
) && !sh
->batch_head
) {
4289 spin_lock(&sh
->stripe_lock
);
4290 /* Cannot process 'sync' concurrently with 'discard' */
4291 if (!test_bit(STRIPE_DISCARD
, &sh
->state
) &&
4292 test_and_clear_bit(STRIPE_SYNC_REQUESTED
, &sh
->state
)) {
4293 set_bit(STRIPE_SYNCING
, &sh
->state
);
4294 clear_bit(STRIPE_INSYNC
, &sh
->state
);
4295 clear_bit(STRIPE_REPLACED
, &sh
->state
);
4297 spin_unlock(&sh
->stripe_lock
);
4299 clear_bit(STRIPE_DELAYED
, &sh
->state
);
4301 pr_debug("handling stripe %llu, state=%#lx cnt=%d, "
4302 "pd_idx=%d, qd_idx=%d\n, check:%d, reconstruct:%d\n",
4303 (unsigned long long)sh
->sector
, sh
->state
,
4304 atomic_read(&sh
->count
), sh
->pd_idx
, sh
->qd_idx
,
4305 sh
->check_state
, sh
->reconstruct_state
);
4307 analyse_stripe(sh
, &s
);
4309 if (s
.handle_bad_blocks
) {
4310 set_bit(STRIPE_HANDLE
, &sh
->state
);
4314 if (unlikely(s
.blocked_rdev
)) {
4315 if (s
.syncing
|| s
.expanding
|| s
.expanded
||
4316 s
.replacing
|| s
.to_write
|| s
.written
) {
4317 set_bit(STRIPE_HANDLE
, &sh
->state
);
4320 /* There is nothing for the blocked_rdev to block */
4321 rdev_dec_pending(s
.blocked_rdev
, conf
->mddev
);
4322 s
.blocked_rdev
= NULL
;
4325 if (s
.to_fill
&& !test_bit(STRIPE_BIOFILL_RUN
, &sh
->state
)) {
4326 set_bit(STRIPE_OP_BIOFILL
, &s
.ops_request
);
4327 set_bit(STRIPE_BIOFILL_RUN
, &sh
->state
);
4330 pr_debug("locked=%d uptodate=%d to_read=%d"
4331 " to_write=%d failed=%d failed_num=%d,%d\n",
4332 s
.locked
, s
.uptodate
, s
.to_read
, s
.to_write
, s
.failed
,
4333 s
.failed_num
[0], s
.failed_num
[1]);
4334 /* check if the array has lost more than max_degraded devices and,
4335 * if so, some requests might need to be failed.
4337 if (s
.failed
> conf
->max_degraded
) {
4338 sh
->check_state
= 0;
4339 sh
->reconstruct_state
= 0;
4340 if (s
.to_read
+s
.to_write
+s
.written
)
4341 handle_failed_stripe(conf
, sh
, &s
, disks
, &s
.return_bi
);
4342 if (s
.syncing
+ s
.replacing
)
4343 handle_failed_sync(conf
, sh
, &s
);
4346 /* Now we check to see if any write operations have recently
4350 if (sh
->reconstruct_state
== reconstruct_state_prexor_drain_result
)
4352 if (sh
->reconstruct_state
== reconstruct_state_drain_result
||
4353 sh
->reconstruct_state
== reconstruct_state_prexor_drain_result
) {
4354 sh
->reconstruct_state
= reconstruct_state_idle
;
4356 /* All the 'written' buffers and the parity block are ready to
4357 * be written back to disk
4359 BUG_ON(!test_bit(R5_UPTODATE
, &sh
->dev
[sh
->pd_idx
].flags
) &&
4360 !test_bit(R5_Discard
, &sh
->dev
[sh
->pd_idx
].flags
));
4361 BUG_ON(sh
->qd_idx
>= 0 &&
4362 !test_bit(R5_UPTODATE
, &sh
->dev
[sh
->qd_idx
].flags
) &&
4363 !test_bit(R5_Discard
, &sh
->dev
[sh
->qd_idx
].flags
));
4364 for (i
= disks
; i
--; ) {
4365 struct r5dev
*dev
= &sh
->dev
[i
];
4366 if (test_bit(R5_LOCKED
, &dev
->flags
) &&
4367 (i
== sh
->pd_idx
|| i
== sh
->qd_idx
||
4369 pr_debug("Writing block %d\n", i
);
4370 set_bit(R5_Wantwrite
, &dev
->flags
);
4375 if (!test_bit(R5_Insync
, &dev
->flags
) ||
4376 ((i
== sh
->pd_idx
|| i
== sh
->qd_idx
) &&
4378 set_bit(STRIPE_INSYNC
, &sh
->state
);
4381 if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
4382 s
.dec_preread_active
= 1;
4386 * might be able to return some write requests if the parity blocks
4387 * are safe, or on a failed drive
4389 pdev
= &sh
->dev
[sh
->pd_idx
];
4390 s
.p_failed
= (s
.failed
>= 1 && s
.failed_num
[0] == sh
->pd_idx
)
4391 || (s
.failed
>= 2 && s
.failed_num
[1] == sh
->pd_idx
);
4392 qdev
= &sh
->dev
[sh
->qd_idx
];
4393 s
.q_failed
= (s
.failed
>= 1 && s
.failed_num
[0] == sh
->qd_idx
)
4394 || (s
.failed
>= 2 && s
.failed_num
[1] == sh
->qd_idx
)
4398 (s
.p_failed
|| ((test_bit(R5_Insync
, &pdev
->flags
)
4399 && !test_bit(R5_LOCKED
, &pdev
->flags
)
4400 && (test_bit(R5_UPTODATE
, &pdev
->flags
) ||
4401 test_bit(R5_Discard
, &pdev
->flags
))))) &&
4402 (s
.q_failed
|| ((test_bit(R5_Insync
, &qdev
->flags
)
4403 && !test_bit(R5_LOCKED
, &qdev
->flags
)
4404 && (test_bit(R5_UPTODATE
, &qdev
->flags
) ||
4405 test_bit(R5_Discard
, &qdev
->flags
))))))
4406 handle_stripe_clean_event(conf
, sh
, disks
, &s
.return_bi
);
4408 /* Now we might consider reading some blocks, either to check/generate
4409 * parity, or to satisfy requests
4410 * or to load a block that is being partially written.
4412 if (s
.to_read
|| s
.non_overwrite
4413 || (conf
->level
== 6 && s
.to_write
&& s
.failed
)
4414 || (s
.syncing
&& (s
.uptodate
+ s
.compute
< disks
))
4417 handle_stripe_fill(sh
, &s
, disks
);
4419 /* Now to consider new write requests and what else, if anything
4420 * should be read. We do not handle new writes when:
4421 * 1/ A 'write' operation (copy+xor) is already in flight.
4422 * 2/ A 'check' operation is in flight, as it may clobber the parity
4425 if (s
.to_write
&& !sh
->reconstruct_state
&& !sh
->check_state
)
4426 handle_stripe_dirtying(conf
, sh
, &s
, disks
);
4428 /* maybe we need to check and possibly fix the parity for this stripe
4429 * Any reads will already have been scheduled, so we just see if enough
4430 * data is available. The parity check is held off while parity
4431 * dependent operations are in flight.
4433 if (sh
->check_state
||
4434 (s
.syncing
&& s
.locked
== 0 &&
4435 !test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
) &&
4436 !test_bit(STRIPE_INSYNC
, &sh
->state
))) {
4437 if (conf
->level
== 6)
4438 handle_parity_checks6(conf
, sh
, &s
, disks
);
4440 handle_parity_checks5(conf
, sh
, &s
, disks
);
4443 if ((s
.replacing
|| s
.syncing
) && s
.locked
== 0
4444 && !test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
)
4445 && !test_bit(STRIPE_REPLACED
, &sh
->state
)) {
4446 /* Write out to replacement devices where possible */
4447 for (i
= 0; i
< conf
->raid_disks
; i
++)
4448 if (test_bit(R5_NeedReplace
, &sh
->dev
[i
].flags
)) {
4449 WARN_ON(!test_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
));
4450 set_bit(R5_WantReplace
, &sh
->dev
[i
].flags
);
4451 set_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
4455 set_bit(STRIPE_INSYNC
, &sh
->state
);
4456 set_bit(STRIPE_REPLACED
, &sh
->state
);
4458 if ((s
.syncing
|| s
.replacing
) && s
.locked
== 0 &&
4459 !test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
) &&
4460 test_bit(STRIPE_INSYNC
, &sh
->state
)) {
4461 md_done_sync(conf
->mddev
, STRIPE_SECTORS
, 1);
4462 clear_bit(STRIPE_SYNCING
, &sh
->state
);
4463 if (test_and_clear_bit(R5_Overlap
, &sh
->dev
[sh
->pd_idx
].flags
))
4464 wake_up(&conf
->wait_for_overlap
);
4467 /* If the failed drives are just a ReadError, then we might need
4468 * to progress the repair/check process
4470 if (s
.failed
<= conf
->max_degraded
&& !conf
->mddev
->ro
)
4471 for (i
= 0; i
< s
.failed
; i
++) {
4472 struct r5dev
*dev
= &sh
->dev
[s
.failed_num
[i
]];
4473 if (test_bit(R5_ReadError
, &dev
->flags
)
4474 && !test_bit(R5_LOCKED
, &dev
->flags
)
4475 && test_bit(R5_UPTODATE
, &dev
->flags
)
4477 if (!test_bit(R5_ReWrite
, &dev
->flags
)) {
4478 set_bit(R5_Wantwrite
, &dev
->flags
);
4479 set_bit(R5_ReWrite
, &dev
->flags
);
4480 set_bit(R5_LOCKED
, &dev
->flags
);
4483 /* let's read it back */
4484 set_bit(R5_Wantread
, &dev
->flags
);
4485 set_bit(R5_LOCKED
, &dev
->flags
);
4491 /* Finish reconstruct operations initiated by the expansion process */
4492 if (sh
->reconstruct_state
== reconstruct_state_result
) {
4493 struct stripe_head
*sh_src
4494 = get_active_stripe(conf
, sh
->sector
, 1, 1, 1);
4495 if (sh_src
&& test_bit(STRIPE_EXPAND_SOURCE
, &sh_src
->state
)) {
4496 /* sh cannot be written until sh_src has been read.
4497 * so arrange for sh to be delayed a little
4499 set_bit(STRIPE_DELAYED
, &sh
->state
);
4500 set_bit(STRIPE_HANDLE
, &sh
->state
);
4501 if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE
,
4503 atomic_inc(&conf
->preread_active_stripes
);
4504 release_stripe(sh_src
);
4508 release_stripe(sh_src
);
4510 sh
->reconstruct_state
= reconstruct_state_idle
;
4511 clear_bit(STRIPE_EXPANDING
, &sh
->state
);
4512 for (i
= conf
->raid_disks
; i
--; ) {
4513 set_bit(R5_Wantwrite
, &sh
->dev
[i
].flags
);
4514 set_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
4519 if (s
.expanded
&& test_bit(STRIPE_EXPANDING
, &sh
->state
) &&
4520 !sh
->reconstruct_state
) {
4521 /* Need to write out all blocks after computing parity */
4522 sh
->disks
= conf
->raid_disks
;
4523 stripe_set_idx(sh
->sector
, conf
, 0, sh
);
4524 schedule_reconstruction(sh
, &s
, 1, 1);
4525 } else if (s
.expanded
&& !sh
->reconstruct_state
&& s
.locked
== 0) {
4526 clear_bit(STRIPE_EXPAND_READY
, &sh
->state
);
4527 atomic_dec(&conf
->reshape_stripes
);
4528 wake_up(&conf
->wait_for_overlap
);
4529 md_done_sync(conf
->mddev
, STRIPE_SECTORS
, 1);
4532 if (s
.expanding
&& s
.locked
== 0 &&
4533 !test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
))
4534 handle_stripe_expansion(conf
, sh
);
4537 /* wait for this device to become unblocked */
4538 if (unlikely(s
.blocked_rdev
)) {
4539 if (conf
->mddev
->external
)
4540 md_wait_for_blocked_rdev(s
.blocked_rdev
,
4543 /* Internal metadata will immediately
4544 * be written by raid5d, so we don't
4545 * need to wait here.
4547 rdev_dec_pending(s
.blocked_rdev
,
4551 if (s
.handle_bad_blocks
)
4552 for (i
= disks
; i
--; ) {
4553 struct md_rdev
*rdev
;
4554 struct r5dev
*dev
= &sh
->dev
[i
];
4555 if (test_and_clear_bit(R5_WriteError
, &dev
->flags
)) {
4556 /* We own a safe reference to the rdev */
4557 rdev
= conf
->disks
[i
].rdev
;
4558 if (!rdev_set_badblocks(rdev
, sh
->sector
,
4560 md_error(conf
->mddev
, rdev
);
4561 rdev_dec_pending(rdev
, conf
->mddev
);
4563 if (test_and_clear_bit(R5_MadeGood
, &dev
->flags
)) {
4564 rdev
= conf
->disks
[i
].rdev
;
4565 rdev_clear_badblocks(rdev
, sh
->sector
,
4567 rdev_dec_pending(rdev
, conf
->mddev
);
4569 if (test_and_clear_bit(R5_MadeGoodRepl
, &dev
->flags
)) {
4570 rdev
= conf
->disks
[i
].replacement
;
4572 /* rdev have been moved down */
4573 rdev
= conf
->disks
[i
].rdev
;
4574 rdev_clear_badblocks(rdev
, sh
->sector
,
4576 rdev_dec_pending(rdev
, conf
->mddev
);
4581 raid_run_ops(sh
, s
.ops_request
);
4585 if (s
.dec_preread_active
) {
4586 /* We delay this until after ops_run_io so that if make_request
4587 * is waiting on a flush, it won't continue until the writes
4588 * have actually been submitted.
4590 atomic_dec(&conf
->preread_active_stripes
);
4591 if (atomic_read(&conf
->preread_active_stripes
) <
4593 md_wakeup_thread(conf
->mddev
->thread
);
4596 return_io(s
.return_bi
);
4598 clear_bit_unlock(STRIPE_ACTIVE
, &sh
->state
);
4601 static void raid5_activate_delayed(struct r5conf
*conf
)
4603 if (atomic_read(&conf
->preread_active_stripes
) < IO_THRESHOLD
) {
4604 while (!list_empty(&conf
->delayed_list
)) {
4605 struct list_head
*l
= conf
->delayed_list
.next
;
4606 struct stripe_head
*sh
;
4607 sh
= list_entry(l
, struct stripe_head
, lru
);
4609 clear_bit(STRIPE_DELAYED
, &sh
->state
);
4610 if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
4611 atomic_inc(&conf
->preread_active_stripes
);
4612 list_add_tail(&sh
->lru
, &conf
->hold_list
);
4613 raid5_wakeup_stripe_thread(sh
);
4618 static void activate_bit_delay(struct r5conf
*conf
,
4619 struct list_head
*temp_inactive_list
)
4621 /* device_lock is held */
4622 struct list_head head
;
4623 list_add(&head
, &conf
->bitmap_list
);
4624 list_del_init(&conf
->bitmap_list
);
4625 while (!list_empty(&head
)) {
4626 struct stripe_head
*sh
= list_entry(head
.next
, struct stripe_head
, lru
);
4628 list_del_init(&sh
->lru
);
4629 atomic_inc(&sh
->count
);
4630 hash
= sh
->hash_lock_index
;
4631 __release_stripe(conf
, sh
, &temp_inactive_list
[hash
]);
4635 static int raid5_congested(struct mddev
*mddev
, int bits
)
4637 struct r5conf
*conf
= mddev
->private;
4639 /* No difference between reads and writes. Just check
4640 * how busy the stripe_cache is
4643 if (test_bit(R5_INACTIVE_BLOCKED
, &conf
->cache_state
))
4647 if (atomic_read(&conf
->empty_inactive_list_nr
))
4653 /* We want read requests to align with chunks where possible,
4654 * but write requests don't need to.
4656 static int raid5_mergeable_bvec(struct mddev
*mddev
,
4657 struct bvec_merge_data
*bvm
,
4658 struct bio_vec
*biovec
)
4660 sector_t sector
= bvm
->bi_sector
+ get_start_sect(bvm
->bi_bdev
);
4662 unsigned int chunk_sectors
= mddev
->chunk_sectors
;
4663 unsigned int bio_sectors
= bvm
->bi_size
>> 9;
4666 * always allow writes to be mergeable, read as well if array
4667 * is degraded as we'll go through stripe cache anyway.
4669 if ((bvm
->bi_rw
& 1) == WRITE
|| mddev
->degraded
)
4670 return biovec
->bv_len
;
4672 if (mddev
->new_chunk_sectors
< mddev
->chunk_sectors
)
4673 chunk_sectors
= mddev
->new_chunk_sectors
;
4674 max
= (chunk_sectors
- ((sector
& (chunk_sectors
- 1)) + bio_sectors
)) << 9;
4675 if (max
< 0) max
= 0;
4676 if (max
<= biovec
->bv_len
&& bio_sectors
== 0)
4677 return biovec
->bv_len
;
4682 static int in_chunk_boundary(struct mddev
*mddev
, struct bio
*bio
)
4684 sector_t sector
= bio
->bi_iter
.bi_sector
+ get_start_sect(bio
->bi_bdev
);
4685 unsigned int chunk_sectors
= mddev
->chunk_sectors
;
4686 unsigned int bio_sectors
= bio_sectors(bio
);
4688 if (mddev
->new_chunk_sectors
< mddev
->chunk_sectors
)
4689 chunk_sectors
= mddev
->new_chunk_sectors
;
4690 return chunk_sectors
>=
4691 ((sector
& (chunk_sectors
- 1)) + bio_sectors
);
4695 * add bio to the retry LIFO ( in O(1) ... we are in interrupt )
4696 * later sampled by raid5d.
4698 static void add_bio_to_retry(struct bio
*bi
,struct r5conf
*conf
)
4700 unsigned long flags
;
4702 spin_lock_irqsave(&conf
->device_lock
, flags
);
4704 bi
->bi_next
= conf
->retry_read_aligned_list
;
4705 conf
->retry_read_aligned_list
= bi
;
4707 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
4708 md_wakeup_thread(conf
->mddev
->thread
);
4711 static struct bio
*remove_bio_from_retry(struct r5conf
*conf
)
4715 bi
= conf
->retry_read_aligned
;
4717 conf
->retry_read_aligned
= NULL
;
4720 bi
= conf
->retry_read_aligned_list
;
4722 conf
->retry_read_aligned_list
= bi
->bi_next
;
4725 * this sets the active strip count to 1 and the processed
4726 * strip count to zero (upper 8 bits)
4728 raid5_set_bi_stripes(bi
, 1); /* biased count of active stripes */
4735 * The "raid5_align_endio" should check if the read succeeded and if it
4736 * did, call bio_endio on the original bio (having bio_put the new bio
4738 * If the read failed..
4740 static void raid5_align_endio(struct bio
*bi
, int error
)
4742 struct bio
* raid_bi
= bi
->bi_private
;
4743 struct mddev
*mddev
;
4744 struct r5conf
*conf
;
4745 int uptodate
= test_bit(BIO_UPTODATE
, &bi
->bi_flags
);
4746 struct md_rdev
*rdev
;
4750 rdev
= (void*)raid_bi
->bi_next
;
4751 raid_bi
->bi_next
= NULL
;
4752 mddev
= rdev
->mddev
;
4753 conf
= mddev
->private;
4755 rdev_dec_pending(rdev
, conf
->mddev
);
4757 if (!error
&& uptodate
) {
4758 trace_block_bio_complete(bdev_get_queue(raid_bi
->bi_bdev
),
4760 bio_endio(raid_bi
, 0);
4761 if (atomic_dec_and_test(&conf
->active_aligned_reads
))
4762 wake_up(&conf
->wait_for_stripe
);
4766 pr_debug("raid5_align_endio : io error...handing IO for a retry\n");
4768 add_bio_to_retry(raid_bi
, conf
);
4771 static int bio_fits_rdev(struct bio
*bi
)
4773 struct request_queue
*q
= bdev_get_queue(bi
->bi_bdev
);
4775 if (bio_sectors(bi
) > queue_max_sectors(q
))
4777 blk_recount_segments(q
, bi
);
4778 if (bi
->bi_phys_segments
> queue_max_segments(q
))
4781 if (q
->merge_bvec_fn
)
4782 /* it's too hard to apply the merge_bvec_fn at this stage,
4790 static int chunk_aligned_read(struct mddev
*mddev
, struct bio
* raid_bio
)
4792 struct r5conf
*conf
= mddev
->private;
4794 struct bio
* align_bi
;
4795 struct md_rdev
*rdev
;
4796 sector_t end_sector
;
4798 if (!in_chunk_boundary(mddev
, raid_bio
)) {
4799 pr_debug("chunk_aligned_read : non aligned\n");
4803 * use bio_clone_mddev to make a copy of the bio
4805 align_bi
= bio_clone_mddev(raid_bio
, GFP_NOIO
, mddev
);
4809 * set bi_end_io to a new function, and set bi_private to the
4812 align_bi
->bi_end_io
= raid5_align_endio
;
4813 align_bi
->bi_private
= raid_bio
;
4817 align_bi
->bi_iter
.bi_sector
=
4818 raid5_compute_sector(conf
, raid_bio
->bi_iter
.bi_sector
,
4821 end_sector
= bio_end_sector(align_bi
);
4823 rdev
= rcu_dereference(conf
->disks
[dd_idx
].replacement
);
4824 if (!rdev
|| test_bit(Faulty
, &rdev
->flags
) ||
4825 rdev
->recovery_offset
< end_sector
) {
4826 rdev
= rcu_dereference(conf
->disks
[dd_idx
].rdev
);
4828 (test_bit(Faulty
, &rdev
->flags
) ||
4829 !(test_bit(In_sync
, &rdev
->flags
) ||
4830 rdev
->recovery_offset
>= end_sector
)))
4837 atomic_inc(&rdev
->nr_pending
);
4839 raid_bio
->bi_next
= (void*)rdev
;
4840 align_bi
->bi_bdev
= rdev
->bdev
;
4841 __clear_bit(BIO_SEG_VALID
, &align_bi
->bi_flags
);
4843 if (!bio_fits_rdev(align_bi
) ||
4844 is_badblock(rdev
, align_bi
->bi_iter
.bi_sector
,
4845 bio_sectors(align_bi
),
4846 &first_bad
, &bad_sectors
)) {
4847 /* too big in some way, or has a known bad block */
4849 rdev_dec_pending(rdev
, mddev
);
4853 /* No reshape active, so we can trust rdev->data_offset */
4854 align_bi
->bi_iter
.bi_sector
+= rdev
->data_offset
;
4856 spin_lock_irq(&conf
->device_lock
);
4857 wait_event_lock_irq(conf
->wait_for_stripe
,
4860 atomic_inc(&conf
->active_aligned_reads
);
4861 spin_unlock_irq(&conf
->device_lock
);
4864 trace_block_bio_remap(bdev_get_queue(align_bi
->bi_bdev
),
4865 align_bi
, disk_devt(mddev
->gendisk
),
4866 raid_bio
->bi_iter
.bi_sector
);
4867 generic_make_request(align_bi
);
4876 /* __get_priority_stripe - get the next stripe to process
4878 * Full stripe writes are allowed to pass preread active stripes up until
4879 * the bypass_threshold is exceeded. In general the bypass_count
4880 * increments when the handle_list is handled before the hold_list; however, it
4881 * will not be incremented when STRIPE_IO_STARTED is sampled set signifying a
4882 * stripe with in flight i/o. The bypass_count will be reset when the
4883 * head of the hold_list has changed, i.e. the head was promoted to the
4886 static struct stripe_head
*__get_priority_stripe(struct r5conf
*conf
, int group
)
4888 struct stripe_head
*sh
= NULL
, *tmp
;
4889 struct list_head
*handle_list
= NULL
;
4890 struct r5worker_group
*wg
= NULL
;
4892 if (conf
->worker_cnt_per_group
== 0) {
4893 handle_list
= &conf
->handle_list
;
4894 } else if (group
!= ANY_GROUP
) {
4895 handle_list
= &conf
->worker_groups
[group
].handle_list
;
4896 wg
= &conf
->worker_groups
[group
];
4899 for (i
= 0; i
< conf
->group_cnt
; i
++) {
4900 handle_list
= &conf
->worker_groups
[i
].handle_list
;
4901 wg
= &conf
->worker_groups
[i
];
4902 if (!list_empty(handle_list
))
4907 pr_debug("%s: handle: %s hold: %s full_writes: %d bypass_count: %d\n",
4909 list_empty(handle_list
) ? "empty" : "busy",
4910 list_empty(&conf
->hold_list
) ? "empty" : "busy",
4911 atomic_read(&conf
->pending_full_writes
), conf
->bypass_count
);
4913 if (!list_empty(handle_list
)) {
4914 sh
= list_entry(handle_list
->next
, typeof(*sh
), lru
);
4916 if (list_empty(&conf
->hold_list
))
4917 conf
->bypass_count
= 0;
4918 else if (!test_bit(STRIPE_IO_STARTED
, &sh
->state
)) {
4919 if (conf
->hold_list
.next
== conf
->last_hold
)
4920 conf
->bypass_count
++;
4922 conf
->last_hold
= conf
->hold_list
.next
;
4923 conf
->bypass_count
-= conf
->bypass_threshold
;
4924 if (conf
->bypass_count
< 0)
4925 conf
->bypass_count
= 0;
4928 } else if (!list_empty(&conf
->hold_list
) &&
4929 ((conf
->bypass_threshold
&&
4930 conf
->bypass_count
> conf
->bypass_threshold
) ||
4931 atomic_read(&conf
->pending_full_writes
) == 0)) {
4933 list_for_each_entry(tmp
, &conf
->hold_list
, lru
) {
4934 if (conf
->worker_cnt_per_group
== 0 ||
4935 group
== ANY_GROUP
||
4936 !cpu_online(tmp
->cpu
) ||
4937 cpu_to_group(tmp
->cpu
) == group
) {
4944 conf
->bypass_count
-= conf
->bypass_threshold
;
4945 if (conf
->bypass_count
< 0)
4946 conf
->bypass_count
= 0;
4958 list_del_init(&sh
->lru
);
4959 BUG_ON(atomic_inc_return(&sh
->count
) != 1);
4963 struct raid5_plug_cb
{
4964 struct blk_plug_cb cb
;
4965 struct list_head list
;
4966 struct list_head temp_inactive_list
[NR_STRIPE_HASH_LOCKS
];
4969 static void raid5_unplug(struct blk_plug_cb
*blk_cb
, bool from_schedule
)
4971 struct raid5_plug_cb
*cb
= container_of(
4972 blk_cb
, struct raid5_plug_cb
, cb
);
4973 struct stripe_head
*sh
;
4974 struct mddev
*mddev
= cb
->cb
.data
;
4975 struct r5conf
*conf
= mddev
->private;
4979 if (cb
->list
.next
&& !list_empty(&cb
->list
)) {
4980 spin_lock_irq(&conf
->device_lock
);
4981 while (!list_empty(&cb
->list
)) {
4982 sh
= list_first_entry(&cb
->list
, struct stripe_head
, lru
);
4983 list_del_init(&sh
->lru
);
4985 * avoid race release_stripe_plug() sees
4986 * STRIPE_ON_UNPLUG_LIST clear but the stripe
4987 * is still in our list
4989 smp_mb__before_atomic();
4990 clear_bit(STRIPE_ON_UNPLUG_LIST
, &sh
->state
);
4992 * STRIPE_ON_RELEASE_LIST could be set here. In that
4993 * case, the count is always > 1 here
4995 hash
= sh
->hash_lock_index
;
4996 __release_stripe(conf
, sh
, &cb
->temp_inactive_list
[hash
]);
4999 spin_unlock_irq(&conf
->device_lock
);
5001 release_inactive_stripe_list(conf
, cb
->temp_inactive_list
,
5002 NR_STRIPE_HASH_LOCKS
);
5004 trace_block_unplug(mddev
->queue
, cnt
, !from_schedule
);
5008 static void release_stripe_plug(struct mddev
*mddev
,
5009 struct stripe_head
*sh
)
5011 struct blk_plug_cb
*blk_cb
= blk_check_plugged(
5012 raid5_unplug
, mddev
,
5013 sizeof(struct raid5_plug_cb
));
5014 struct raid5_plug_cb
*cb
;
5021 cb
= container_of(blk_cb
, struct raid5_plug_cb
, cb
);
5023 if (cb
->list
.next
== NULL
) {
5025 INIT_LIST_HEAD(&cb
->list
);
5026 for (i
= 0; i
< NR_STRIPE_HASH_LOCKS
; i
++)
5027 INIT_LIST_HEAD(cb
->temp_inactive_list
+ i
);
5030 if (!test_and_set_bit(STRIPE_ON_UNPLUG_LIST
, &sh
->state
))
5031 list_add_tail(&sh
->lru
, &cb
->list
);
5036 static void make_discard_request(struct mddev
*mddev
, struct bio
*bi
)
5038 struct r5conf
*conf
= mddev
->private;
5039 sector_t logical_sector
, last_sector
;
5040 struct stripe_head
*sh
;
5044 if (mddev
->reshape_position
!= MaxSector
)
5045 /* Skip discard while reshape is happening */
5048 logical_sector
= bi
->bi_iter
.bi_sector
& ~((sector_t
)STRIPE_SECTORS
-1);
5049 last_sector
= bi
->bi_iter
.bi_sector
+ (bi
->bi_iter
.bi_size
>>9);
5052 bi
->bi_phys_segments
= 1; /* over-loaded to count active stripes */
5054 stripe_sectors
= conf
->chunk_sectors
*
5055 (conf
->raid_disks
- conf
->max_degraded
);
5056 logical_sector
= DIV_ROUND_UP_SECTOR_T(logical_sector
,
5058 sector_div(last_sector
, stripe_sectors
);
5060 logical_sector
*= conf
->chunk_sectors
;
5061 last_sector
*= conf
->chunk_sectors
;
5063 for (; logical_sector
< last_sector
;
5064 logical_sector
+= STRIPE_SECTORS
) {
5068 sh
= get_active_stripe(conf
, logical_sector
, 0, 0, 0);
5069 prepare_to_wait(&conf
->wait_for_overlap
, &w
,
5070 TASK_UNINTERRUPTIBLE
);
5071 set_bit(R5_Overlap
, &sh
->dev
[sh
->pd_idx
].flags
);
5072 if (test_bit(STRIPE_SYNCING
, &sh
->state
)) {
5077 clear_bit(R5_Overlap
, &sh
->dev
[sh
->pd_idx
].flags
);
5078 spin_lock_irq(&sh
->stripe_lock
);
5079 for (d
= 0; d
< conf
->raid_disks
; d
++) {
5080 if (d
== sh
->pd_idx
|| d
== sh
->qd_idx
)
5082 if (sh
->dev
[d
].towrite
|| sh
->dev
[d
].toread
) {
5083 set_bit(R5_Overlap
, &sh
->dev
[d
].flags
);
5084 spin_unlock_irq(&sh
->stripe_lock
);
5090 set_bit(STRIPE_DISCARD
, &sh
->state
);
5091 finish_wait(&conf
->wait_for_overlap
, &w
);
5092 sh
->overwrite_disks
= 0;
5093 for (d
= 0; d
< conf
->raid_disks
; d
++) {
5094 if (d
== sh
->pd_idx
|| d
== sh
->qd_idx
)
5096 sh
->dev
[d
].towrite
= bi
;
5097 set_bit(R5_OVERWRITE
, &sh
->dev
[d
].flags
);
5098 raid5_inc_bi_active_stripes(bi
);
5099 sh
->overwrite_disks
++;
5101 spin_unlock_irq(&sh
->stripe_lock
);
5102 if (conf
->mddev
->bitmap
) {
5104 d
< conf
->raid_disks
- conf
->max_degraded
;
5106 bitmap_startwrite(mddev
->bitmap
,
5110 sh
->bm_seq
= conf
->seq_flush
+ 1;
5111 set_bit(STRIPE_BIT_DELAY
, &sh
->state
);
5114 set_bit(STRIPE_HANDLE
, &sh
->state
);
5115 clear_bit(STRIPE_DELAYED
, &sh
->state
);
5116 if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
5117 atomic_inc(&conf
->preread_active_stripes
);
5118 release_stripe_plug(mddev
, sh
);
5121 remaining
= raid5_dec_bi_active_stripes(bi
);
5122 if (remaining
== 0) {
5123 md_write_end(mddev
);
5128 static void make_request(struct mddev
*mddev
, struct bio
* bi
)
5130 struct r5conf
*conf
= mddev
->private;
5132 sector_t new_sector
;
5133 sector_t logical_sector
, last_sector
;
5134 struct stripe_head
*sh
;
5135 const int rw
= bio_data_dir(bi
);
5140 if (unlikely(bi
->bi_rw
& REQ_FLUSH
)) {
5141 md_flush_request(mddev
, bi
);
5145 md_write_start(mddev
, bi
);
5148 * If array is degraded, better not do chunk aligned read because
5149 * later we might have to read it again in order to reconstruct
5150 * data on failed drives.
5152 if (rw
== READ
&& mddev
->degraded
== 0 &&
5153 mddev
->reshape_position
== MaxSector
&&
5154 chunk_aligned_read(mddev
,bi
))
5157 if (unlikely(bi
->bi_rw
& REQ_DISCARD
)) {
5158 make_discard_request(mddev
, bi
);
5162 logical_sector
= bi
->bi_iter
.bi_sector
& ~((sector_t
)STRIPE_SECTORS
-1);
5163 last_sector
= bio_end_sector(bi
);
5165 bi
->bi_phys_segments
= 1; /* over-loaded to count active stripes */
5167 prepare_to_wait(&conf
->wait_for_overlap
, &w
, TASK_UNINTERRUPTIBLE
);
5168 for (;logical_sector
< last_sector
; logical_sector
+= STRIPE_SECTORS
) {
5174 seq
= read_seqcount_begin(&conf
->gen_lock
);
5177 prepare_to_wait(&conf
->wait_for_overlap
, &w
,
5178 TASK_UNINTERRUPTIBLE
);
5179 if (unlikely(conf
->reshape_progress
!= MaxSector
)) {
5180 /* spinlock is needed as reshape_progress may be
5181 * 64bit on a 32bit platform, and so it might be
5182 * possible to see a half-updated value
5183 * Of course reshape_progress could change after
5184 * the lock is dropped, so once we get a reference
5185 * to the stripe that we think it is, we will have
5188 spin_lock_irq(&conf
->device_lock
);
5189 if (mddev
->reshape_backwards
5190 ? logical_sector
< conf
->reshape_progress
5191 : logical_sector
>= conf
->reshape_progress
) {
5194 if (mddev
->reshape_backwards
5195 ? logical_sector
< conf
->reshape_safe
5196 : logical_sector
>= conf
->reshape_safe
) {
5197 spin_unlock_irq(&conf
->device_lock
);
5203 spin_unlock_irq(&conf
->device_lock
);
5206 new_sector
= raid5_compute_sector(conf
, logical_sector
,
5209 pr_debug("raid456: make_request, sector %llu logical %llu\n",
5210 (unsigned long long)new_sector
,
5211 (unsigned long long)logical_sector
);
5213 sh
= get_active_stripe(conf
, new_sector
, previous
,
5214 (bi
->bi_rw
&RWA_MASK
), 0);
5216 if (unlikely(previous
)) {
5217 /* expansion might have moved on while waiting for a
5218 * stripe, so we must do the range check again.
5219 * Expansion could still move past after this
5220 * test, but as we are holding a reference to
5221 * 'sh', we know that if that happens,
5222 * STRIPE_EXPANDING will get set and the expansion
5223 * won't proceed until we finish with the stripe.
5226 spin_lock_irq(&conf
->device_lock
);
5227 if (mddev
->reshape_backwards
5228 ? logical_sector
>= conf
->reshape_progress
5229 : logical_sector
< conf
->reshape_progress
)
5230 /* mismatch, need to try again */
5232 spin_unlock_irq(&conf
->device_lock
);
5240 if (read_seqcount_retry(&conf
->gen_lock
, seq
)) {
5241 /* Might have got the wrong stripe_head
5249 logical_sector
>= mddev
->suspend_lo
&&
5250 logical_sector
< mddev
->suspend_hi
) {
5252 /* As the suspend_* range is controlled by
5253 * userspace, we want an interruptible
5256 flush_signals(current
);
5257 prepare_to_wait(&conf
->wait_for_overlap
,
5258 &w
, TASK_INTERRUPTIBLE
);
5259 if (logical_sector
>= mddev
->suspend_lo
&&
5260 logical_sector
< mddev
->suspend_hi
) {
5267 if (test_bit(STRIPE_EXPANDING
, &sh
->state
) ||
5268 !add_stripe_bio(sh
, bi
, dd_idx
, rw
, previous
)) {
5269 /* Stripe is busy expanding or
5270 * add failed due to overlap. Flush everything
5273 md_wakeup_thread(mddev
->thread
);
5279 set_bit(STRIPE_HANDLE
, &sh
->state
);
5280 clear_bit(STRIPE_DELAYED
, &sh
->state
);
5281 if ((!sh
->batch_head
|| sh
== sh
->batch_head
) &&
5282 (bi
->bi_rw
& REQ_SYNC
) &&
5283 !test_and_set_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
5284 atomic_inc(&conf
->preread_active_stripes
);
5285 release_stripe_plug(mddev
, sh
);
5287 /* cannot get stripe for read-ahead, just give-up */
5288 clear_bit(BIO_UPTODATE
, &bi
->bi_flags
);
5292 finish_wait(&conf
->wait_for_overlap
, &w
);
5294 remaining
= raid5_dec_bi_active_stripes(bi
);
5295 if (remaining
== 0) {
5298 md_write_end(mddev
);
5300 trace_block_bio_complete(bdev_get_queue(bi
->bi_bdev
),
5306 static sector_t
raid5_size(struct mddev
*mddev
, sector_t sectors
, int raid_disks
);
5308 static sector_t
reshape_request(struct mddev
*mddev
, sector_t sector_nr
, int *skipped
)
5310 /* reshaping is quite different to recovery/resync so it is
5311 * handled quite separately ... here.
5313 * On each call to sync_request, we gather one chunk worth of
5314 * destination stripes and flag them as expanding.
5315 * Then we find all the source stripes and request reads.
5316 * As the reads complete, handle_stripe will copy the data
5317 * into the destination stripe and release that stripe.
5319 struct r5conf
*conf
= mddev
->private;
5320 struct stripe_head
*sh
;
5321 sector_t first_sector
, last_sector
;
5322 int raid_disks
= conf
->previous_raid_disks
;
5323 int data_disks
= raid_disks
- conf
->max_degraded
;
5324 int new_data_disks
= conf
->raid_disks
- conf
->max_degraded
;
5327 sector_t writepos
, readpos
, safepos
;
5328 sector_t stripe_addr
;
5329 int reshape_sectors
;
5330 struct list_head stripes
;
5332 if (sector_nr
== 0) {
5333 /* If restarting in the middle, skip the initial sectors */
5334 if (mddev
->reshape_backwards
&&
5335 conf
->reshape_progress
< raid5_size(mddev
, 0, 0)) {
5336 sector_nr
= raid5_size(mddev
, 0, 0)
5337 - conf
->reshape_progress
;
5338 } else if (!mddev
->reshape_backwards
&&
5339 conf
->reshape_progress
> 0)
5340 sector_nr
= conf
->reshape_progress
;
5341 sector_div(sector_nr
, new_data_disks
);
5343 mddev
->curr_resync_completed
= sector_nr
;
5344 sysfs_notify(&mddev
->kobj
, NULL
, "sync_completed");
5350 /* We need to process a full chunk at a time.
5351 * If old and new chunk sizes differ, we need to process the
5354 if (mddev
->new_chunk_sectors
> mddev
->chunk_sectors
)
5355 reshape_sectors
= mddev
->new_chunk_sectors
;
5357 reshape_sectors
= mddev
->chunk_sectors
;
5359 /* We update the metadata at least every 10 seconds, or when
5360 * the data about to be copied would over-write the source of
5361 * the data at the front of the range. i.e. one new_stripe
5362 * along from reshape_progress new_maps to after where
5363 * reshape_safe old_maps to
5365 writepos
= conf
->reshape_progress
;
5366 sector_div(writepos
, new_data_disks
);
5367 readpos
= conf
->reshape_progress
;
5368 sector_div(readpos
, data_disks
);
5369 safepos
= conf
->reshape_safe
;
5370 sector_div(safepos
, data_disks
);
5371 if (mddev
->reshape_backwards
) {
5372 writepos
-= min_t(sector_t
, reshape_sectors
, writepos
);
5373 readpos
+= reshape_sectors
;
5374 safepos
+= reshape_sectors
;
5376 writepos
+= reshape_sectors
;
5377 readpos
-= min_t(sector_t
, reshape_sectors
, readpos
);
5378 safepos
-= min_t(sector_t
, reshape_sectors
, safepos
);
5381 /* Having calculated the 'writepos' possibly use it
5382 * to set 'stripe_addr' which is where we will write to.
5384 if (mddev
->reshape_backwards
) {
5385 BUG_ON(conf
->reshape_progress
== 0);
5386 stripe_addr
= writepos
;
5387 BUG_ON((mddev
->dev_sectors
&
5388 ~((sector_t
)reshape_sectors
- 1))
5389 - reshape_sectors
- stripe_addr
5392 BUG_ON(writepos
!= sector_nr
+ reshape_sectors
);
5393 stripe_addr
= sector_nr
;
5396 /* 'writepos' is the most advanced device address we might write.
5397 * 'readpos' is the least advanced device address we might read.
5398 * 'safepos' is the least address recorded in the metadata as having
5400 * If there is a min_offset_diff, these are adjusted either by
5401 * increasing the safepos/readpos if diff is negative, or
5402 * increasing writepos if diff is positive.
5403 * If 'readpos' is then behind 'writepos', there is no way that we can
5404 * ensure safety in the face of a crash - that must be done by userspace
5405 * making a backup of the data. So in that case there is no particular
5406 * rush to update metadata.
5407 * Otherwise if 'safepos' is behind 'writepos', then we really need to
5408 * update the metadata to advance 'safepos' to match 'readpos' so that
5409 * we can be safe in the event of a crash.
5410 * So we insist on updating metadata if safepos is behind writepos and
5411 * readpos is beyond writepos.
5412 * In any case, update the metadata every 10 seconds.
5413 * Maybe that number should be configurable, but I'm not sure it is
5414 * worth it.... maybe it could be a multiple of safemode_delay???
5416 if (conf
->min_offset_diff
< 0) {
5417 safepos
+= -conf
->min_offset_diff
;
5418 readpos
+= -conf
->min_offset_diff
;
5420 writepos
+= conf
->min_offset_diff
;
5422 if ((mddev
->reshape_backwards
5423 ? (safepos
> writepos
&& readpos
< writepos
)
5424 : (safepos
< writepos
&& readpos
> writepos
)) ||
5425 time_after(jiffies
, conf
->reshape_checkpoint
+ 10*HZ
)) {
5426 /* Cannot proceed until we've updated the superblock... */
5427 wait_event(conf
->wait_for_overlap
,
5428 atomic_read(&conf
->reshape_stripes
)==0
5429 || test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
));
5430 if (atomic_read(&conf
->reshape_stripes
) != 0)
5432 mddev
->reshape_position
= conf
->reshape_progress
;
5433 mddev
->curr_resync_completed
= sector_nr
;
5434 conf
->reshape_checkpoint
= jiffies
;
5435 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
5436 md_wakeup_thread(mddev
->thread
);
5437 wait_event(mddev
->sb_wait
, mddev
->flags
== 0 ||
5438 test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
));
5439 if (test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
))
5441 spin_lock_irq(&conf
->device_lock
);
5442 conf
->reshape_safe
= mddev
->reshape_position
;
5443 spin_unlock_irq(&conf
->device_lock
);
5444 wake_up(&conf
->wait_for_overlap
);
5445 sysfs_notify(&mddev
->kobj
, NULL
, "sync_completed");
5448 INIT_LIST_HEAD(&stripes
);
5449 for (i
= 0; i
< reshape_sectors
; i
+= STRIPE_SECTORS
) {
5451 int skipped_disk
= 0;
5452 sh
= get_active_stripe(conf
, stripe_addr
+i
, 0, 0, 1);
5453 set_bit(STRIPE_EXPANDING
, &sh
->state
);
5454 atomic_inc(&conf
->reshape_stripes
);
5455 /* If any of this stripe is beyond the end of the old
5456 * array, then we need to zero those blocks
5458 for (j
=sh
->disks
; j
--;) {
5460 if (j
== sh
->pd_idx
)
5462 if (conf
->level
== 6 &&
5465 s
= compute_blocknr(sh
, j
, 0);
5466 if (s
< raid5_size(mddev
, 0, 0)) {
5470 memset(page_address(sh
->dev
[j
].page
), 0, STRIPE_SIZE
);
5471 set_bit(R5_Expanded
, &sh
->dev
[j
].flags
);
5472 set_bit(R5_UPTODATE
, &sh
->dev
[j
].flags
);
5474 if (!skipped_disk
) {
5475 set_bit(STRIPE_EXPAND_READY
, &sh
->state
);
5476 set_bit(STRIPE_HANDLE
, &sh
->state
);
5478 list_add(&sh
->lru
, &stripes
);
5480 spin_lock_irq(&conf
->device_lock
);
5481 if (mddev
->reshape_backwards
)
5482 conf
->reshape_progress
-= reshape_sectors
* new_data_disks
;
5484 conf
->reshape_progress
+= reshape_sectors
* new_data_disks
;
5485 spin_unlock_irq(&conf
->device_lock
);
5486 /* Ok, those stripe are ready. We can start scheduling
5487 * reads on the source stripes.
5488 * The source stripes are determined by mapping the first and last
5489 * block on the destination stripes.
5492 raid5_compute_sector(conf
, stripe_addr
*(new_data_disks
),
5495 raid5_compute_sector(conf
, ((stripe_addr
+reshape_sectors
)
5496 * new_data_disks
- 1),
5498 if (last_sector
>= mddev
->dev_sectors
)
5499 last_sector
= mddev
->dev_sectors
- 1;
5500 while (first_sector
<= last_sector
) {
5501 sh
= get_active_stripe(conf
, first_sector
, 1, 0, 1);
5502 set_bit(STRIPE_EXPAND_SOURCE
, &sh
->state
);
5503 set_bit(STRIPE_HANDLE
, &sh
->state
);
5505 first_sector
+= STRIPE_SECTORS
;
5507 /* Now that the sources are clearly marked, we can release
5508 * the destination stripes
5510 while (!list_empty(&stripes
)) {
5511 sh
= list_entry(stripes
.next
, struct stripe_head
, lru
);
5512 list_del_init(&sh
->lru
);
5515 /* If this takes us to the resync_max point where we have to pause,
5516 * then we need to write out the superblock.
5518 sector_nr
+= reshape_sectors
;
5519 if ((sector_nr
- mddev
->curr_resync_completed
) * 2
5520 >= mddev
->resync_max
- mddev
->curr_resync_completed
) {
5521 /* Cannot proceed until we've updated the superblock... */
5522 wait_event(conf
->wait_for_overlap
,
5523 atomic_read(&conf
->reshape_stripes
) == 0
5524 || test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
));
5525 if (atomic_read(&conf
->reshape_stripes
) != 0)
5527 mddev
->reshape_position
= conf
->reshape_progress
;
5528 mddev
->curr_resync_completed
= sector_nr
;
5529 conf
->reshape_checkpoint
= jiffies
;
5530 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
5531 md_wakeup_thread(mddev
->thread
);
5532 wait_event(mddev
->sb_wait
,
5533 !test_bit(MD_CHANGE_DEVS
, &mddev
->flags
)
5534 || test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
));
5535 if (test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
))
5537 spin_lock_irq(&conf
->device_lock
);
5538 conf
->reshape_safe
= mddev
->reshape_position
;
5539 spin_unlock_irq(&conf
->device_lock
);
5540 wake_up(&conf
->wait_for_overlap
);
5541 sysfs_notify(&mddev
->kobj
, NULL
, "sync_completed");
5544 return reshape_sectors
;
5547 static inline sector_t
sync_request(struct mddev
*mddev
, sector_t sector_nr
, int *skipped
)
5549 struct r5conf
*conf
= mddev
->private;
5550 struct stripe_head
*sh
;
5551 sector_t max_sector
= mddev
->dev_sectors
;
5552 sector_t sync_blocks
;
5553 int still_degraded
= 0;
5556 if (sector_nr
>= max_sector
) {
5557 /* just being told to finish up .. nothing much to do */
5559 if (test_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
)) {
5564 if (mddev
->curr_resync
< max_sector
) /* aborted */
5565 bitmap_end_sync(mddev
->bitmap
, mddev
->curr_resync
,
5567 else /* completed sync */
5569 bitmap_close_sync(mddev
->bitmap
);
5574 /* Allow raid5_quiesce to complete */
5575 wait_event(conf
->wait_for_overlap
, conf
->quiesce
!= 2);
5577 if (test_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
))
5578 return reshape_request(mddev
, sector_nr
, skipped
);
5580 /* No need to check resync_max as we never do more than one
5581 * stripe, and as resync_max will always be on a chunk boundary,
5582 * if the check in md_do_sync didn't fire, there is no chance
5583 * of overstepping resync_max here
5586 /* if there is too many failed drives and we are trying
5587 * to resync, then assert that we are finished, because there is
5588 * nothing we can do.
5590 if (mddev
->degraded
>= conf
->max_degraded
&&
5591 test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
)) {
5592 sector_t rv
= mddev
->dev_sectors
- sector_nr
;
5596 if (!test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
) &&
5598 !bitmap_start_sync(mddev
->bitmap
, sector_nr
, &sync_blocks
, 1) &&
5599 sync_blocks
>= STRIPE_SECTORS
) {
5600 /* we can skip this block, and probably more */
5601 sync_blocks
/= STRIPE_SECTORS
;
5603 return sync_blocks
* STRIPE_SECTORS
; /* keep things rounded to whole stripes */
5606 bitmap_cond_end_sync(mddev
->bitmap
, sector_nr
);
5608 sh
= get_active_stripe(conf
, sector_nr
, 0, 1, 0);
5610 sh
= get_active_stripe(conf
, sector_nr
, 0, 0, 0);
5611 /* make sure we don't swamp the stripe cache if someone else
5612 * is trying to get access
5614 schedule_timeout_uninterruptible(1);
5616 /* Need to check if array will still be degraded after recovery/resync
5617 * Note in case of > 1 drive failures it's possible we're rebuilding
5618 * one drive while leaving another faulty drive in array.
5621 for (i
= 0; i
< conf
->raid_disks
; i
++) {
5622 struct md_rdev
*rdev
= ACCESS_ONCE(conf
->disks
[i
].rdev
);
5624 if (rdev
== NULL
|| test_bit(Faulty
, &rdev
->flags
))
5629 bitmap_start_sync(mddev
->bitmap
, sector_nr
, &sync_blocks
, still_degraded
);
5631 set_bit(STRIPE_SYNC_REQUESTED
, &sh
->state
);
5632 set_bit(STRIPE_HANDLE
, &sh
->state
);
5636 return STRIPE_SECTORS
;
5639 static int retry_aligned_read(struct r5conf
*conf
, struct bio
*raid_bio
)
5641 /* We may not be able to submit a whole bio at once as there
5642 * may not be enough stripe_heads available.
5643 * We cannot pre-allocate enough stripe_heads as we may need
5644 * more than exist in the cache (if we allow ever large chunks).
5645 * So we do one stripe head at a time and record in
5646 * ->bi_hw_segments how many have been done.
5648 * We *know* that this entire raid_bio is in one chunk, so
5649 * it will be only one 'dd_idx' and only need one call to raid5_compute_sector.
5651 struct stripe_head
*sh
;
5653 sector_t sector
, logical_sector
, last_sector
;
5658 logical_sector
= raid_bio
->bi_iter
.bi_sector
&
5659 ~((sector_t
)STRIPE_SECTORS
-1);
5660 sector
= raid5_compute_sector(conf
, logical_sector
,
5662 last_sector
= bio_end_sector(raid_bio
);
5664 for (; logical_sector
< last_sector
;
5665 logical_sector
+= STRIPE_SECTORS
,
5666 sector
+= STRIPE_SECTORS
,
5669 if (scnt
< raid5_bi_processed_stripes(raid_bio
))
5670 /* already done this stripe */
5673 sh
= get_active_stripe(conf
, sector
, 0, 1, 1);
5676 /* failed to get a stripe - must wait */
5677 raid5_set_bi_processed_stripes(raid_bio
, scnt
);
5678 conf
->retry_read_aligned
= raid_bio
;
5682 if (!add_stripe_bio(sh
, raid_bio
, dd_idx
, 0, 0)) {
5684 raid5_set_bi_processed_stripes(raid_bio
, scnt
);
5685 conf
->retry_read_aligned
= raid_bio
;
5689 set_bit(R5_ReadNoMerge
, &sh
->dev
[dd_idx
].flags
);
5694 remaining
= raid5_dec_bi_active_stripes(raid_bio
);
5695 if (remaining
== 0) {
5696 trace_block_bio_complete(bdev_get_queue(raid_bio
->bi_bdev
),
5698 bio_endio(raid_bio
, 0);
5700 if (atomic_dec_and_test(&conf
->active_aligned_reads
))
5701 wake_up(&conf
->wait_for_stripe
);
5705 static int handle_active_stripes(struct r5conf
*conf
, int group
,
5706 struct r5worker
*worker
,
5707 struct list_head
*temp_inactive_list
)
5709 struct stripe_head
*batch
[MAX_STRIPE_BATCH
], *sh
;
5710 int i
, batch_size
= 0, hash
;
5711 bool release_inactive
= false;
5713 while (batch_size
< MAX_STRIPE_BATCH
&&
5714 (sh
= __get_priority_stripe(conf
, group
)) != NULL
)
5715 batch
[batch_size
++] = sh
;
5717 if (batch_size
== 0) {
5718 for (i
= 0; i
< NR_STRIPE_HASH_LOCKS
; i
++)
5719 if (!list_empty(temp_inactive_list
+ i
))
5721 if (i
== NR_STRIPE_HASH_LOCKS
)
5723 release_inactive
= true;
5725 spin_unlock_irq(&conf
->device_lock
);
5727 release_inactive_stripe_list(conf
, temp_inactive_list
,
5728 NR_STRIPE_HASH_LOCKS
);
5730 if (release_inactive
) {
5731 spin_lock_irq(&conf
->device_lock
);
5735 for (i
= 0; i
< batch_size
; i
++)
5736 handle_stripe(batch
[i
]);
5740 spin_lock_irq(&conf
->device_lock
);
5741 for (i
= 0; i
< batch_size
; i
++) {
5742 hash
= batch
[i
]->hash_lock_index
;
5743 __release_stripe(conf
, batch
[i
], &temp_inactive_list
[hash
]);
5748 static void raid5_do_work(struct work_struct
*work
)
5750 struct r5worker
*worker
= container_of(work
, struct r5worker
, work
);
5751 struct r5worker_group
*group
= worker
->group
;
5752 struct r5conf
*conf
= group
->conf
;
5753 int group_id
= group
- conf
->worker_groups
;
5755 struct blk_plug plug
;
5757 pr_debug("+++ raid5worker active\n");
5759 blk_start_plug(&plug
);
5761 spin_lock_irq(&conf
->device_lock
);
5763 int batch_size
, released
;
5765 released
= release_stripe_list(conf
, worker
->temp_inactive_list
);
5767 batch_size
= handle_active_stripes(conf
, group_id
, worker
,
5768 worker
->temp_inactive_list
);
5769 worker
->working
= false;
5770 if (!batch_size
&& !released
)
5772 handled
+= batch_size
;
5774 pr_debug("%d stripes handled\n", handled
);
5776 spin_unlock_irq(&conf
->device_lock
);
5777 blk_finish_plug(&plug
);
5779 pr_debug("--- raid5worker inactive\n");
5783 * This is our raid5 kernel thread.
5785 * We scan the hash table for stripes which can be handled now.
5786 * During the scan, completed stripes are saved for us by the interrupt
5787 * handler, so that they will not have to wait for our next wakeup.
5789 static void raid5d(struct md_thread
*thread
)
5791 struct mddev
*mddev
= thread
->mddev
;
5792 struct r5conf
*conf
= mddev
->private;
5794 struct blk_plug plug
;
5796 pr_debug("+++ raid5d active\n");
5798 md_check_recovery(mddev
);
5800 blk_start_plug(&plug
);
5802 spin_lock_irq(&conf
->device_lock
);
5805 int batch_size
, released
;
5807 released
= release_stripe_list(conf
, conf
->temp_inactive_list
);
5809 clear_bit(R5_DID_ALLOC
, &conf
->cache_state
);
5812 !list_empty(&conf
->bitmap_list
)) {
5813 /* Now is a good time to flush some bitmap updates */
5815 spin_unlock_irq(&conf
->device_lock
);
5816 bitmap_unplug(mddev
->bitmap
);
5817 spin_lock_irq(&conf
->device_lock
);
5818 conf
->seq_write
= conf
->seq_flush
;
5819 activate_bit_delay(conf
, conf
->temp_inactive_list
);
5821 raid5_activate_delayed(conf
);
5823 while ((bio
= remove_bio_from_retry(conf
))) {
5825 spin_unlock_irq(&conf
->device_lock
);
5826 ok
= retry_aligned_read(conf
, bio
);
5827 spin_lock_irq(&conf
->device_lock
);
5833 batch_size
= handle_active_stripes(conf
, ANY_GROUP
, NULL
,
5834 conf
->temp_inactive_list
);
5835 if (!batch_size
&& !released
)
5837 handled
+= batch_size
;
5839 if (mddev
->flags
& ~(1<<MD_CHANGE_PENDING
)) {
5840 spin_unlock_irq(&conf
->device_lock
);
5841 md_check_recovery(mddev
);
5842 spin_lock_irq(&conf
->device_lock
);
5845 pr_debug("%d stripes handled\n", handled
);
5847 spin_unlock_irq(&conf
->device_lock
);
5848 if (test_and_clear_bit(R5_ALLOC_MORE
, &conf
->cache_state
)) {
5849 grow_one_stripe(conf
, __GFP_NOWARN
);
5850 /* Set flag even if allocation failed. This helps
5851 * slow down allocation requests when mem is short
5853 set_bit(R5_DID_ALLOC
, &conf
->cache_state
);
5856 async_tx_issue_pending_all();
5857 blk_finish_plug(&plug
);
5859 pr_debug("--- raid5d inactive\n");
5863 raid5_show_stripe_cache_size(struct mddev
*mddev
, char *page
)
5865 struct r5conf
*conf
;
5867 spin_lock(&mddev
->lock
);
5868 conf
= mddev
->private;
5870 ret
= sprintf(page
, "%d\n", conf
->min_nr_stripes
);
5871 spin_unlock(&mddev
->lock
);
5876 raid5_set_cache_size(struct mddev
*mddev
, int size
)
5878 struct r5conf
*conf
= mddev
->private;
5881 if (size
<= 16 || size
> 32768)
5884 conf
->min_nr_stripes
= size
;
5885 while (size
< conf
->max_nr_stripes
&&
5886 drop_one_stripe(conf
))
5890 err
= md_allow_write(mddev
);
5894 while (size
> conf
->max_nr_stripes
)
5895 if (!grow_one_stripe(conf
, GFP_KERNEL
))
5900 EXPORT_SYMBOL(raid5_set_cache_size
);
5903 raid5_store_stripe_cache_size(struct mddev
*mddev
, const char *page
, size_t len
)
5905 struct r5conf
*conf
;
5909 if (len
>= PAGE_SIZE
)
5911 if (kstrtoul(page
, 10, &new))
5913 err
= mddev_lock(mddev
);
5916 conf
= mddev
->private;
5920 err
= raid5_set_cache_size(mddev
, new);
5921 mddev_unlock(mddev
);
5926 static struct md_sysfs_entry
5927 raid5_stripecache_size
= __ATTR(stripe_cache_size
, S_IRUGO
| S_IWUSR
,
5928 raid5_show_stripe_cache_size
,
5929 raid5_store_stripe_cache_size
);
5932 raid5_show_rmw_level(struct mddev
*mddev
, char *page
)
5934 struct r5conf
*conf
= mddev
->private;
5936 return sprintf(page
, "%d\n", conf
->rmw_level
);
5942 raid5_store_rmw_level(struct mddev
*mddev
, const char *page
, size_t len
)
5944 struct r5conf
*conf
= mddev
->private;
5950 if (len
>= PAGE_SIZE
)
5953 if (kstrtoul(page
, 10, &new))
5956 if (new != PARITY_DISABLE_RMW
&& !raid6_call
.xor_syndrome
)
5959 if (new != PARITY_DISABLE_RMW
&&
5960 new != PARITY_ENABLE_RMW
&&
5961 new != PARITY_PREFER_RMW
)
5964 conf
->rmw_level
= new;
5968 static struct md_sysfs_entry
5969 raid5_rmw_level
= __ATTR(rmw_level
, S_IRUGO
| S_IWUSR
,
5970 raid5_show_rmw_level
,
5971 raid5_store_rmw_level
);
5975 raid5_show_preread_threshold(struct mddev
*mddev
, char *page
)
5977 struct r5conf
*conf
;
5979 spin_lock(&mddev
->lock
);
5980 conf
= mddev
->private;
5982 ret
= sprintf(page
, "%d\n", conf
->bypass_threshold
);
5983 spin_unlock(&mddev
->lock
);
5988 raid5_store_preread_threshold(struct mddev
*mddev
, const char *page
, size_t len
)
5990 struct r5conf
*conf
;
5994 if (len
>= PAGE_SIZE
)
5996 if (kstrtoul(page
, 10, &new))
5999 err
= mddev_lock(mddev
);
6002 conf
= mddev
->private;
6005 else if (new > conf
->min_nr_stripes
)
6008 conf
->bypass_threshold
= new;
6009 mddev_unlock(mddev
);
6013 static struct md_sysfs_entry
6014 raid5_preread_bypass_threshold
= __ATTR(preread_bypass_threshold
,
6016 raid5_show_preread_threshold
,
6017 raid5_store_preread_threshold
);
6020 raid5_show_skip_copy(struct mddev
*mddev
, char *page
)
6022 struct r5conf
*conf
;
6024 spin_lock(&mddev
->lock
);
6025 conf
= mddev
->private;
6027 ret
= sprintf(page
, "%d\n", conf
->skip_copy
);
6028 spin_unlock(&mddev
->lock
);
6033 raid5_store_skip_copy(struct mddev
*mddev
, const char *page
, size_t len
)
6035 struct r5conf
*conf
;
6039 if (len
>= PAGE_SIZE
)
6041 if (kstrtoul(page
, 10, &new))
6045 err
= mddev_lock(mddev
);
6048 conf
= mddev
->private;
6051 else if (new != conf
->skip_copy
) {
6052 mddev_suspend(mddev
);
6053 conf
->skip_copy
= new;
6055 mddev
->queue
->backing_dev_info
.capabilities
|=
6056 BDI_CAP_STABLE_WRITES
;
6058 mddev
->queue
->backing_dev_info
.capabilities
&=
6059 ~BDI_CAP_STABLE_WRITES
;
6060 mddev_resume(mddev
);
6062 mddev_unlock(mddev
);
6066 static struct md_sysfs_entry
6067 raid5_skip_copy
= __ATTR(skip_copy
, S_IRUGO
| S_IWUSR
,
6068 raid5_show_skip_copy
,
6069 raid5_store_skip_copy
);
6072 stripe_cache_active_show(struct mddev
*mddev
, char *page
)
6074 struct r5conf
*conf
= mddev
->private;
6076 return sprintf(page
, "%d\n", atomic_read(&conf
->active_stripes
));
6081 static struct md_sysfs_entry
6082 raid5_stripecache_active
= __ATTR_RO(stripe_cache_active
);
6085 raid5_show_group_thread_cnt(struct mddev
*mddev
, char *page
)
6087 struct r5conf
*conf
;
6089 spin_lock(&mddev
->lock
);
6090 conf
= mddev
->private;
6092 ret
= sprintf(page
, "%d\n", conf
->worker_cnt_per_group
);
6093 spin_unlock(&mddev
->lock
);
6097 static int alloc_thread_groups(struct r5conf
*conf
, int cnt
,
6099 int *worker_cnt_per_group
,
6100 struct r5worker_group
**worker_groups
);
6102 raid5_store_group_thread_cnt(struct mddev
*mddev
, const char *page
, size_t len
)
6104 struct r5conf
*conf
;
6107 struct r5worker_group
*new_groups
, *old_groups
;
6108 int group_cnt
, worker_cnt_per_group
;
6110 if (len
>= PAGE_SIZE
)
6112 if (kstrtoul(page
, 10, &new))
6115 err
= mddev_lock(mddev
);
6118 conf
= mddev
->private;
6121 else if (new != conf
->worker_cnt_per_group
) {
6122 mddev_suspend(mddev
);
6124 old_groups
= conf
->worker_groups
;
6126 flush_workqueue(raid5_wq
);
6128 err
= alloc_thread_groups(conf
, new,
6129 &group_cnt
, &worker_cnt_per_group
,
6132 spin_lock_irq(&conf
->device_lock
);
6133 conf
->group_cnt
= group_cnt
;
6134 conf
->worker_cnt_per_group
= worker_cnt_per_group
;
6135 conf
->worker_groups
= new_groups
;
6136 spin_unlock_irq(&conf
->device_lock
);
6139 kfree(old_groups
[0].workers
);
6142 mddev_resume(mddev
);
6144 mddev_unlock(mddev
);
6149 static struct md_sysfs_entry
6150 raid5_group_thread_cnt
= __ATTR(group_thread_cnt
, S_IRUGO
| S_IWUSR
,
6151 raid5_show_group_thread_cnt
,
6152 raid5_store_group_thread_cnt
);
6154 static struct attribute
*raid5_attrs
[] = {
6155 &raid5_stripecache_size
.attr
,
6156 &raid5_stripecache_active
.attr
,
6157 &raid5_preread_bypass_threshold
.attr
,
6158 &raid5_group_thread_cnt
.attr
,
6159 &raid5_skip_copy
.attr
,
6160 &raid5_rmw_level
.attr
,
6163 static struct attribute_group raid5_attrs_group
= {
6165 .attrs
= raid5_attrs
,
6168 static int alloc_thread_groups(struct r5conf
*conf
, int cnt
,
6170 int *worker_cnt_per_group
,
6171 struct r5worker_group
**worker_groups
)
6175 struct r5worker
*workers
;
6177 *worker_cnt_per_group
= cnt
;
6180 *worker_groups
= NULL
;
6183 *group_cnt
= num_possible_nodes();
6184 size
= sizeof(struct r5worker
) * cnt
;
6185 workers
= kzalloc(size
* *group_cnt
, GFP_NOIO
);
6186 *worker_groups
= kzalloc(sizeof(struct r5worker_group
) *
6187 *group_cnt
, GFP_NOIO
);
6188 if (!*worker_groups
|| !workers
) {
6190 kfree(*worker_groups
);
6194 for (i
= 0; i
< *group_cnt
; i
++) {
6195 struct r5worker_group
*group
;
6197 group
= &(*worker_groups
)[i
];
6198 INIT_LIST_HEAD(&group
->handle_list
);
6200 group
->workers
= workers
+ i
* cnt
;
6202 for (j
= 0; j
< cnt
; j
++) {
6203 struct r5worker
*worker
= group
->workers
+ j
;
6204 worker
->group
= group
;
6205 INIT_WORK(&worker
->work
, raid5_do_work
);
6207 for (k
= 0; k
< NR_STRIPE_HASH_LOCKS
; k
++)
6208 INIT_LIST_HEAD(worker
->temp_inactive_list
+ k
);
6215 static void free_thread_groups(struct r5conf
*conf
)
6217 if (conf
->worker_groups
)
6218 kfree(conf
->worker_groups
[0].workers
);
6219 kfree(conf
->worker_groups
);
6220 conf
->worker_groups
= NULL
;
6224 raid5_size(struct mddev
*mddev
, sector_t sectors
, int raid_disks
)
6226 struct r5conf
*conf
= mddev
->private;
6229 sectors
= mddev
->dev_sectors
;
6231 /* size is defined by the smallest of previous and new size */
6232 raid_disks
= min(conf
->raid_disks
, conf
->previous_raid_disks
);
6234 sectors
&= ~((sector_t
)mddev
->chunk_sectors
- 1);
6235 sectors
&= ~((sector_t
)mddev
->new_chunk_sectors
- 1);
6236 return sectors
* (raid_disks
- conf
->max_degraded
);
6239 static void free_scratch_buffer(struct r5conf
*conf
, struct raid5_percpu
*percpu
)
6241 safe_put_page(percpu
->spare_page
);
6242 if (percpu
->scribble
)
6243 flex_array_free(percpu
->scribble
);
6244 percpu
->spare_page
= NULL
;
6245 percpu
->scribble
= NULL
;
6248 static int alloc_scratch_buffer(struct r5conf
*conf
, struct raid5_percpu
*percpu
)
6250 if (conf
->level
== 6 && !percpu
->spare_page
)
6251 percpu
->spare_page
= alloc_page(GFP_KERNEL
);
6252 if (!percpu
->scribble
)
6253 percpu
->scribble
= scribble_alloc(max(conf
->raid_disks
,
6254 conf
->previous_raid_disks
),
6255 max(conf
->chunk_sectors
,
6256 conf
->prev_chunk_sectors
)
6260 if (!percpu
->scribble
|| (conf
->level
== 6 && !percpu
->spare_page
)) {
6261 free_scratch_buffer(conf
, percpu
);
6268 static void raid5_free_percpu(struct r5conf
*conf
)
6275 #ifdef CONFIG_HOTPLUG_CPU
6276 unregister_cpu_notifier(&conf
->cpu_notify
);
6280 for_each_possible_cpu(cpu
)
6281 free_scratch_buffer(conf
, per_cpu_ptr(conf
->percpu
, cpu
));
6284 free_percpu(conf
->percpu
);
6287 static void free_conf(struct r5conf
*conf
)
6289 if (conf
->shrinker
.seeks
)
6290 unregister_shrinker(&conf
->shrinker
);
6291 free_thread_groups(conf
);
6292 shrink_stripes(conf
);
6293 raid5_free_percpu(conf
);
6295 kfree(conf
->stripe_hashtbl
);
6299 #ifdef CONFIG_HOTPLUG_CPU
6300 static int raid456_cpu_notify(struct notifier_block
*nfb
, unsigned long action
,
6303 struct r5conf
*conf
= container_of(nfb
, struct r5conf
, cpu_notify
);
6304 long cpu
= (long)hcpu
;
6305 struct raid5_percpu
*percpu
= per_cpu_ptr(conf
->percpu
, cpu
);
6308 case CPU_UP_PREPARE
:
6309 case CPU_UP_PREPARE_FROZEN
:
6310 if (alloc_scratch_buffer(conf
, percpu
)) {
6311 pr_err("%s: failed memory allocation for cpu%ld\n",
6313 return notifier_from_errno(-ENOMEM
);
6317 case CPU_DEAD_FROZEN
:
6318 free_scratch_buffer(conf
, per_cpu_ptr(conf
->percpu
, cpu
));
6327 static int raid5_alloc_percpu(struct r5conf
*conf
)
6332 conf
->percpu
= alloc_percpu(struct raid5_percpu
);
6336 #ifdef CONFIG_HOTPLUG_CPU
6337 conf
->cpu_notify
.notifier_call
= raid456_cpu_notify
;
6338 conf
->cpu_notify
.priority
= 0;
6339 err
= register_cpu_notifier(&conf
->cpu_notify
);
6345 for_each_present_cpu(cpu
) {
6346 err
= alloc_scratch_buffer(conf
, per_cpu_ptr(conf
->percpu
, cpu
));
6348 pr_err("%s: failed memory allocation for cpu%ld\n",
6358 static unsigned long raid5_cache_scan(struct shrinker
*shrink
,
6359 struct shrink_control
*sc
)
6361 struct r5conf
*conf
= container_of(shrink
, struct r5conf
, shrinker
);
6363 while (ret
< sc
->nr_to_scan
) {
6364 if (drop_one_stripe(conf
) == 0)
6371 static unsigned long raid5_cache_count(struct shrinker
*shrink
,
6372 struct shrink_control
*sc
)
6374 struct r5conf
*conf
= container_of(shrink
, struct r5conf
, shrinker
);
6376 if (conf
->max_nr_stripes
< conf
->min_nr_stripes
)
6377 /* unlikely, but not impossible */
6379 return conf
->max_nr_stripes
- conf
->min_nr_stripes
;
6382 static struct r5conf
*setup_conf(struct mddev
*mddev
)
6384 struct r5conf
*conf
;
6385 int raid_disk
, memory
, max_disks
;
6386 struct md_rdev
*rdev
;
6387 struct disk_info
*disk
;
6390 int group_cnt
, worker_cnt_per_group
;
6391 struct r5worker_group
*new_group
;
6393 if (mddev
->new_level
!= 5
6394 && mddev
->new_level
!= 4
6395 && mddev
->new_level
!= 6) {
6396 printk(KERN_ERR
"md/raid:%s: raid level not set to 4/5/6 (%d)\n",
6397 mdname(mddev
), mddev
->new_level
);
6398 return ERR_PTR(-EIO
);
6400 if ((mddev
->new_level
== 5
6401 && !algorithm_valid_raid5(mddev
->new_layout
)) ||
6402 (mddev
->new_level
== 6
6403 && !algorithm_valid_raid6(mddev
->new_layout
))) {
6404 printk(KERN_ERR
"md/raid:%s: layout %d not supported\n",
6405 mdname(mddev
), mddev
->new_layout
);
6406 return ERR_PTR(-EIO
);
6408 if (mddev
->new_level
== 6 && mddev
->raid_disks
< 4) {
6409 printk(KERN_ERR
"md/raid:%s: not enough configured devices (%d, minimum 4)\n",
6410 mdname(mddev
), mddev
->raid_disks
);
6411 return ERR_PTR(-EINVAL
);
6414 if (!mddev
->new_chunk_sectors
||
6415 (mddev
->new_chunk_sectors
<< 9) % PAGE_SIZE
||
6416 !is_power_of_2(mddev
->new_chunk_sectors
)) {
6417 printk(KERN_ERR
"md/raid:%s: invalid chunk size %d\n",
6418 mdname(mddev
), mddev
->new_chunk_sectors
<< 9);
6419 return ERR_PTR(-EINVAL
);
6422 conf
= kzalloc(sizeof(struct r5conf
), GFP_KERNEL
);
6425 /* Don't enable multi-threading by default*/
6426 if (!alloc_thread_groups(conf
, 0, &group_cnt
, &worker_cnt_per_group
,
6428 conf
->group_cnt
= group_cnt
;
6429 conf
->worker_cnt_per_group
= worker_cnt_per_group
;
6430 conf
->worker_groups
= new_group
;
6433 spin_lock_init(&conf
->device_lock
);
6434 seqcount_init(&conf
->gen_lock
);
6435 init_waitqueue_head(&conf
->wait_for_stripe
);
6436 init_waitqueue_head(&conf
->wait_for_overlap
);
6437 INIT_LIST_HEAD(&conf
->handle_list
);
6438 INIT_LIST_HEAD(&conf
->hold_list
);
6439 INIT_LIST_HEAD(&conf
->delayed_list
);
6440 INIT_LIST_HEAD(&conf
->bitmap_list
);
6441 init_llist_head(&conf
->released_stripes
);
6442 atomic_set(&conf
->active_stripes
, 0);
6443 atomic_set(&conf
->preread_active_stripes
, 0);
6444 atomic_set(&conf
->active_aligned_reads
, 0);
6445 conf
->bypass_threshold
= BYPASS_THRESHOLD
;
6446 conf
->recovery_disabled
= mddev
->recovery_disabled
- 1;
6448 conf
->raid_disks
= mddev
->raid_disks
;
6449 if (mddev
->reshape_position
== MaxSector
)
6450 conf
->previous_raid_disks
= mddev
->raid_disks
;
6452 conf
->previous_raid_disks
= mddev
->raid_disks
- mddev
->delta_disks
;
6453 max_disks
= max(conf
->raid_disks
, conf
->previous_raid_disks
);
6455 conf
->disks
= kzalloc(max_disks
* sizeof(struct disk_info
),
6460 conf
->mddev
= mddev
;
6462 if ((conf
->stripe_hashtbl
= kzalloc(PAGE_SIZE
, GFP_KERNEL
)) == NULL
)
6465 /* We init hash_locks[0] separately to that it can be used
6466 * as the reference lock in the spin_lock_nest_lock() call
6467 * in lock_all_device_hash_locks_irq in order to convince
6468 * lockdep that we know what we are doing.
6470 spin_lock_init(conf
->hash_locks
);
6471 for (i
= 1; i
< NR_STRIPE_HASH_LOCKS
; i
++)
6472 spin_lock_init(conf
->hash_locks
+ i
);
6474 for (i
= 0; i
< NR_STRIPE_HASH_LOCKS
; i
++)
6475 INIT_LIST_HEAD(conf
->inactive_list
+ i
);
6477 for (i
= 0; i
< NR_STRIPE_HASH_LOCKS
; i
++)
6478 INIT_LIST_HEAD(conf
->temp_inactive_list
+ i
);
6480 conf
->level
= mddev
->new_level
;
6481 conf
->chunk_sectors
= mddev
->new_chunk_sectors
;
6482 if (raid5_alloc_percpu(conf
) != 0)
6485 pr_debug("raid456: run(%s) called.\n", mdname(mddev
));
6487 rdev_for_each(rdev
, mddev
) {
6488 raid_disk
= rdev
->raid_disk
;
6489 if (raid_disk
>= max_disks
6492 disk
= conf
->disks
+ raid_disk
;
6494 if (test_bit(Replacement
, &rdev
->flags
)) {
6495 if (disk
->replacement
)
6497 disk
->replacement
= rdev
;
6504 if (test_bit(In_sync
, &rdev
->flags
)) {
6505 char b
[BDEVNAME_SIZE
];
6506 printk(KERN_INFO
"md/raid:%s: device %s operational as raid"
6508 mdname(mddev
), bdevname(rdev
->bdev
, b
), raid_disk
);
6509 } else if (rdev
->saved_raid_disk
!= raid_disk
)
6510 /* Cannot rely on bitmap to complete recovery */
6514 conf
->level
= mddev
->new_level
;
6515 if (conf
->level
== 6) {
6516 conf
->max_degraded
= 2;
6517 if (raid6_call
.xor_syndrome
)
6518 conf
->rmw_level
= PARITY_ENABLE_RMW
;
6520 conf
->rmw_level
= PARITY_DISABLE_RMW
;
6522 conf
->max_degraded
= 1;
6523 conf
->rmw_level
= PARITY_ENABLE_RMW
;
6525 conf
->algorithm
= mddev
->new_layout
;
6526 conf
->reshape_progress
= mddev
->reshape_position
;
6527 if (conf
->reshape_progress
!= MaxSector
) {
6528 conf
->prev_chunk_sectors
= mddev
->chunk_sectors
;
6529 conf
->prev_algo
= mddev
->layout
;
6532 conf
->min_nr_stripes
= NR_STRIPES
;
6533 memory
= conf
->min_nr_stripes
* (sizeof(struct stripe_head
) +
6534 max_disks
* ((sizeof(struct bio
) + PAGE_SIZE
))) / 1024;
6535 atomic_set(&conf
->empty_inactive_list_nr
, NR_STRIPE_HASH_LOCKS
);
6536 if (grow_stripes(conf
, conf
->min_nr_stripes
)) {
6538 "md/raid:%s: couldn't allocate %dkB for buffers\n",
6539 mdname(mddev
), memory
);
6542 printk(KERN_INFO
"md/raid:%s: allocated %dkB\n",
6543 mdname(mddev
), memory
);
6545 * Losing a stripe head costs more than the time to refill it,
6546 * it reduces the queue depth and so can hurt throughput.
6547 * So set it rather large, scaled by number of devices.
6549 conf
->shrinker
.seeks
= DEFAULT_SEEKS
* conf
->raid_disks
* 4;
6550 conf
->shrinker
.scan_objects
= raid5_cache_scan
;
6551 conf
->shrinker
.count_objects
= raid5_cache_count
;
6552 conf
->shrinker
.batch
= 128;
6553 conf
->shrinker
.flags
= 0;
6554 register_shrinker(&conf
->shrinker
);
6556 sprintf(pers_name
, "raid%d", mddev
->new_level
);
6557 conf
->thread
= md_register_thread(raid5d
, mddev
, pers_name
);
6558 if (!conf
->thread
) {
6560 "md/raid:%s: couldn't allocate thread.\n",
6570 return ERR_PTR(-EIO
);
6572 return ERR_PTR(-ENOMEM
);
6575 static int only_parity(int raid_disk
, int algo
, int raid_disks
, int max_degraded
)
6578 case ALGORITHM_PARITY_0
:
6579 if (raid_disk
< max_degraded
)
6582 case ALGORITHM_PARITY_N
:
6583 if (raid_disk
>= raid_disks
- max_degraded
)
6586 case ALGORITHM_PARITY_0_6
:
6587 if (raid_disk
== 0 ||
6588 raid_disk
== raid_disks
- 1)
6591 case ALGORITHM_LEFT_ASYMMETRIC_6
:
6592 case ALGORITHM_RIGHT_ASYMMETRIC_6
:
6593 case ALGORITHM_LEFT_SYMMETRIC_6
:
6594 case ALGORITHM_RIGHT_SYMMETRIC_6
:
6595 if (raid_disk
== raid_disks
- 1)
6601 static int run(struct mddev
*mddev
)
6603 struct r5conf
*conf
;
6604 int working_disks
= 0;
6605 int dirty_parity_disks
= 0;
6606 struct md_rdev
*rdev
;
6607 sector_t reshape_offset
= 0;
6609 long long min_offset_diff
= 0;
6612 if (mddev
->recovery_cp
!= MaxSector
)
6613 printk(KERN_NOTICE
"md/raid:%s: not clean"
6614 " -- starting background reconstruction\n",
6617 rdev_for_each(rdev
, mddev
) {
6619 if (rdev
->raid_disk
< 0)
6621 diff
= (rdev
->new_data_offset
- rdev
->data_offset
);
6623 min_offset_diff
= diff
;
6625 } else if (mddev
->reshape_backwards
&&
6626 diff
< min_offset_diff
)
6627 min_offset_diff
= diff
;
6628 else if (!mddev
->reshape_backwards
&&
6629 diff
> min_offset_diff
)
6630 min_offset_diff
= diff
;
6633 if (mddev
->reshape_position
!= MaxSector
) {
6634 /* Check that we can continue the reshape.
6635 * Difficulties arise if the stripe we would write to
6636 * next is at or after the stripe we would read from next.
6637 * For a reshape that changes the number of devices, this
6638 * is only possible for a very short time, and mdadm makes
6639 * sure that time appears to have past before assembling
6640 * the array. So we fail if that time hasn't passed.
6641 * For a reshape that keeps the number of devices the same
6642 * mdadm must be monitoring the reshape can keeping the
6643 * critical areas read-only and backed up. It will start
6644 * the array in read-only mode, so we check for that.
6646 sector_t here_new
, here_old
;
6648 int max_degraded
= (mddev
->level
== 6 ? 2 : 1);
6650 if (mddev
->new_level
!= mddev
->level
) {
6651 printk(KERN_ERR
"md/raid:%s: unsupported reshape "
6652 "required - aborting.\n",
6656 old_disks
= mddev
->raid_disks
- mddev
->delta_disks
;
6657 /* reshape_position must be on a new-stripe boundary, and one
6658 * further up in new geometry must map after here in old
6661 here_new
= mddev
->reshape_position
;
6662 if (sector_div(here_new
, mddev
->new_chunk_sectors
*
6663 (mddev
->raid_disks
- max_degraded
))) {
6664 printk(KERN_ERR
"md/raid:%s: reshape_position not "
6665 "on a stripe boundary\n", mdname(mddev
));
6668 reshape_offset
= here_new
* mddev
->new_chunk_sectors
;
6669 /* here_new is the stripe we will write to */
6670 here_old
= mddev
->reshape_position
;
6671 sector_div(here_old
, mddev
->chunk_sectors
*
6672 (old_disks
-max_degraded
));
6673 /* here_old is the first stripe that we might need to read
6675 if (mddev
->delta_disks
== 0) {
6676 if ((here_new
* mddev
->new_chunk_sectors
!=
6677 here_old
* mddev
->chunk_sectors
)) {
6678 printk(KERN_ERR
"md/raid:%s: reshape position is"
6679 " confused - aborting\n", mdname(mddev
));
6682 /* We cannot be sure it is safe to start an in-place
6683 * reshape. It is only safe if user-space is monitoring
6684 * and taking constant backups.
6685 * mdadm always starts a situation like this in
6686 * readonly mode so it can take control before
6687 * allowing any writes. So just check for that.
6689 if (abs(min_offset_diff
) >= mddev
->chunk_sectors
&&
6690 abs(min_offset_diff
) >= mddev
->new_chunk_sectors
)
6691 /* not really in-place - so OK */;
6692 else if (mddev
->ro
== 0) {
6693 printk(KERN_ERR
"md/raid:%s: in-place reshape "
6694 "must be started in read-only mode "
6699 } else if (mddev
->reshape_backwards
6700 ? (here_new
* mddev
->new_chunk_sectors
+ min_offset_diff
<=
6701 here_old
* mddev
->chunk_sectors
)
6702 : (here_new
* mddev
->new_chunk_sectors
>=
6703 here_old
* mddev
->chunk_sectors
+ (-min_offset_diff
))) {
6704 /* Reading from the same stripe as writing to - bad */
6705 printk(KERN_ERR
"md/raid:%s: reshape_position too early for "
6706 "auto-recovery - aborting.\n",
6710 printk(KERN_INFO
"md/raid:%s: reshape will continue\n",
6712 /* OK, we should be able to continue; */
6714 BUG_ON(mddev
->level
!= mddev
->new_level
);
6715 BUG_ON(mddev
->layout
!= mddev
->new_layout
);
6716 BUG_ON(mddev
->chunk_sectors
!= mddev
->new_chunk_sectors
);
6717 BUG_ON(mddev
->delta_disks
!= 0);
6720 if (mddev
->private == NULL
)
6721 conf
= setup_conf(mddev
);
6723 conf
= mddev
->private;
6726 return PTR_ERR(conf
);
6728 conf
->min_offset_diff
= min_offset_diff
;
6729 mddev
->thread
= conf
->thread
;
6730 conf
->thread
= NULL
;
6731 mddev
->private = conf
;
6733 for (i
= 0; i
< conf
->raid_disks
&& conf
->previous_raid_disks
;
6735 rdev
= conf
->disks
[i
].rdev
;
6736 if (!rdev
&& conf
->disks
[i
].replacement
) {
6737 /* The replacement is all we have yet */
6738 rdev
= conf
->disks
[i
].replacement
;
6739 conf
->disks
[i
].replacement
= NULL
;
6740 clear_bit(Replacement
, &rdev
->flags
);
6741 conf
->disks
[i
].rdev
= rdev
;
6745 if (conf
->disks
[i
].replacement
&&
6746 conf
->reshape_progress
!= MaxSector
) {
6747 /* replacements and reshape simply do not mix. */
6748 printk(KERN_ERR
"md: cannot handle concurrent "
6749 "replacement and reshape.\n");
6752 if (test_bit(In_sync
, &rdev
->flags
)) {
6756 /* This disc is not fully in-sync. However if it
6757 * just stored parity (beyond the recovery_offset),
6758 * when we don't need to be concerned about the
6759 * array being dirty.
6760 * When reshape goes 'backwards', we never have
6761 * partially completed devices, so we only need
6762 * to worry about reshape going forwards.
6764 /* Hack because v0.91 doesn't store recovery_offset properly. */
6765 if (mddev
->major_version
== 0 &&
6766 mddev
->minor_version
> 90)
6767 rdev
->recovery_offset
= reshape_offset
;
6769 if (rdev
->recovery_offset
< reshape_offset
) {
6770 /* We need to check old and new layout */
6771 if (!only_parity(rdev
->raid_disk
,
6774 conf
->max_degraded
))
6777 if (!only_parity(rdev
->raid_disk
,
6779 conf
->previous_raid_disks
,
6780 conf
->max_degraded
))
6782 dirty_parity_disks
++;
6786 * 0 for a fully functional array, 1 or 2 for a degraded array.
6788 mddev
->degraded
= calc_degraded(conf
);
6790 if (has_failed(conf
)) {
6791 printk(KERN_ERR
"md/raid:%s: not enough operational devices"
6792 " (%d/%d failed)\n",
6793 mdname(mddev
), mddev
->degraded
, conf
->raid_disks
);
6797 /* device size must be a multiple of chunk size */
6798 mddev
->dev_sectors
&= ~(mddev
->chunk_sectors
- 1);
6799 mddev
->resync_max_sectors
= mddev
->dev_sectors
;
6801 if (mddev
->degraded
> dirty_parity_disks
&&
6802 mddev
->recovery_cp
!= MaxSector
) {
6803 if (mddev
->ok_start_degraded
)
6805 "md/raid:%s: starting dirty degraded array"
6806 " - data corruption possible.\n",
6810 "md/raid:%s: cannot start dirty degraded array.\n",
6816 if (mddev
->degraded
== 0)
6817 printk(KERN_INFO
"md/raid:%s: raid level %d active with %d out of %d"
6818 " devices, algorithm %d\n", mdname(mddev
), conf
->level
,
6819 mddev
->raid_disks
-mddev
->degraded
, mddev
->raid_disks
,
6822 printk(KERN_ALERT
"md/raid:%s: raid level %d active with %d"
6823 " out of %d devices, algorithm %d\n",
6824 mdname(mddev
), conf
->level
,
6825 mddev
->raid_disks
- mddev
->degraded
,
6826 mddev
->raid_disks
, mddev
->new_layout
);
6828 print_raid5_conf(conf
);
6830 if (conf
->reshape_progress
!= MaxSector
) {
6831 conf
->reshape_safe
= conf
->reshape_progress
;
6832 atomic_set(&conf
->reshape_stripes
, 0);
6833 clear_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
);
6834 clear_bit(MD_RECOVERY_CHECK
, &mddev
->recovery
);
6835 set_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
);
6836 set_bit(MD_RECOVERY_RUNNING
, &mddev
->recovery
);
6837 mddev
->sync_thread
= md_register_thread(md_do_sync
, mddev
,
6841 /* Ok, everything is just fine now */
6842 if (mddev
->to_remove
== &raid5_attrs_group
)
6843 mddev
->to_remove
= NULL
;
6844 else if (mddev
->kobj
.sd
&&
6845 sysfs_create_group(&mddev
->kobj
, &raid5_attrs_group
))
6847 "raid5: failed to create sysfs attributes for %s\n",
6849 md_set_array_sectors(mddev
, raid5_size(mddev
, 0, 0));
6853 bool discard_supported
= true;
6854 /* read-ahead size must cover two whole stripes, which
6855 * is 2 * (datadisks) * chunksize where 'n' is the
6856 * number of raid devices
6858 int data_disks
= conf
->previous_raid_disks
- conf
->max_degraded
;
6859 int stripe
= data_disks
*
6860 ((mddev
->chunk_sectors
<< 9) / PAGE_SIZE
);
6861 if (mddev
->queue
->backing_dev_info
.ra_pages
< 2 * stripe
)
6862 mddev
->queue
->backing_dev_info
.ra_pages
= 2 * stripe
;
6864 chunk_size
= mddev
->chunk_sectors
<< 9;
6865 blk_queue_io_min(mddev
->queue
, chunk_size
);
6866 blk_queue_io_opt(mddev
->queue
, chunk_size
*
6867 (conf
->raid_disks
- conf
->max_degraded
));
6868 mddev
->queue
->limits
.raid_partial_stripes_expensive
= 1;
6870 * We can only discard a whole stripe. It doesn't make sense to
6871 * discard data disk but write parity disk
6873 stripe
= stripe
* PAGE_SIZE
;
6874 /* Round up to power of 2, as discard handling
6875 * currently assumes that */
6876 while ((stripe
-1) & stripe
)
6877 stripe
= (stripe
| (stripe
-1)) + 1;
6878 mddev
->queue
->limits
.discard_alignment
= stripe
;
6879 mddev
->queue
->limits
.discard_granularity
= stripe
;
6881 * unaligned part of discard request will be ignored, so can't
6882 * guarantee discard_zeroes_data
6884 mddev
->queue
->limits
.discard_zeroes_data
= 0;
6886 blk_queue_max_write_same_sectors(mddev
->queue
, 0);
6888 rdev_for_each(rdev
, mddev
) {
6889 disk_stack_limits(mddev
->gendisk
, rdev
->bdev
,
6890 rdev
->data_offset
<< 9);
6891 disk_stack_limits(mddev
->gendisk
, rdev
->bdev
,
6892 rdev
->new_data_offset
<< 9);
6894 * discard_zeroes_data is required, otherwise data
6895 * could be lost. Consider a scenario: discard a stripe
6896 * (the stripe could be inconsistent if
6897 * discard_zeroes_data is 0); write one disk of the
6898 * stripe (the stripe could be inconsistent again
6899 * depending on which disks are used to calculate
6900 * parity); the disk is broken; The stripe data of this
6903 if (!blk_queue_discard(bdev_get_queue(rdev
->bdev
)) ||
6904 !bdev_get_queue(rdev
->bdev
)->
6905 limits
.discard_zeroes_data
)
6906 discard_supported
= false;
6907 /* Unfortunately, discard_zeroes_data is not currently
6908 * a guarantee - just a hint. So we only allow DISCARD
6909 * if the sysadmin has confirmed that only safe devices
6910 * are in use by setting a module parameter.
6912 if (!devices_handle_discard_safely
) {
6913 if (discard_supported
) {
6914 pr_info("md/raid456: discard support disabled due to uncertainty.\n");
6915 pr_info("Set raid456.devices_handle_discard_safely=Y to override.\n");
6917 discard_supported
= false;
6921 if (discard_supported
&&
6922 mddev
->queue
->limits
.max_discard_sectors
>= stripe
&&
6923 mddev
->queue
->limits
.discard_granularity
>= stripe
)
6924 queue_flag_set_unlocked(QUEUE_FLAG_DISCARD
,
6927 queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD
,
6933 md_unregister_thread(&mddev
->thread
);
6934 print_raid5_conf(conf
);
6936 mddev
->private = NULL
;
6937 printk(KERN_ALERT
"md/raid:%s: failed to run raid set.\n", mdname(mddev
));
6941 static void raid5_free(struct mddev
*mddev
, void *priv
)
6943 struct r5conf
*conf
= priv
;
6946 mddev
->to_remove
= &raid5_attrs_group
;
6949 static void status(struct seq_file
*seq
, struct mddev
*mddev
)
6951 struct r5conf
*conf
= mddev
->private;
6954 seq_printf(seq
, " level %d, %dk chunk, algorithm %d", mddev
->level
,
6955 mddev
->chunk_sectors
/ 2, mddev
->layout
);
6956 seq_printf (seq
, " [%d/%d] [", conf
->raid_disks
, conf
->raid_disks
- mddev
->degraded
);
6957 for (i
= 0; i
< conf
->raid_disks
; i
++)
6958 seq_printf (seq
, "%s",
6959 conf
->disks
[i
].rdev
&&
6960 test_bit(In_sync
, &conf
->disks
[i
].rdev
->flags
) ? "U" : "_");
6961 seq_printf (seq
, "]");
6964 static void print_raid5_conf (struct r5conf
*conf
)
6967 struct disk_info
*tmp
;
6969 printk(KERN_DEBUG
"RAID conf printout:\n");
6971 printk("(conf==NULL)\n");
6974 printk(KERN_DEBUG
" --- level:%d rd:%d wd:%d\n", conf
->level
,
6976 conf
->raid_disks
- conf
->mddev
->degraded
);
6978 for (i
= 0; i
< conf
->raid_disks
; i
++) {
6979 char b
[BDEVNAME_SIZE
];
6980 tmp
= conf
->disks
+ i
;
6982 printk(KERN_DEBUG
" disk %d, o:%d, dev:%s\n",
6983 i
, !test_bit(Faulty
, &tmp
->rdev
->flags
),
6984 bdevname(tmp
->rdev
->bdev
, b
));
6988 static int raid5_spare_active(struct mddev
*mddev
)
6991 struct r5conf
*conf
= mddev
->private;
6992 struct disk_info
*tmp
;
6994 unsigned long flags
;
6996 for (i
= 0; i
< conf
->raid_disks
; i
++) {
6997 tmp
= conf
->disks
+ i
;
6998 if (tmp
->replacement
6999 && tmp
->replacement
->recovery_offset
== MaxSector
7000 && !test_bit(Faulty
, &tmp
->replacement
->flags
)
7001 && !test_and_set_bit(In_sync
, &tmp
->replacement
->flags
)) {
7002 /* Replacement has just become active. */
7004 || !test_and_clear_bit(In_sync
, &tmp
->rdev
->flags
))
7007 /* Replaced device not technically faulty,
7008 * but we need to be sure it gets removed
7009 * and never re-added.
7011 set_bit(Faulty
, &tmp
->rdev
->flags
);
7012 sysfs_notify_dirent_safe(
7013 tmp
->rdev
->sysfs_state
);
7015 sysfs_notify_dirent_safe(tmp
->replacement
->sysfs_state
);
7016 } else if (tmp
->rdev
7017 && tmp
->rdev
->recovery_offset
== MaxSector
7018 && !test_bit(Faulty
, &tmp
->rdev
->flags
)
7019 && !test_and_set_bit(In_sync
, &tmp
->rdev
->flags
)) {
7021 sysfs_notify_dirent_safe(tmp
->rdev
->sysfs_state
);
7024 spin_lock_irqsave(&conf
->device_lock
, flags
);
7025 mddev
->degraded
= calc_degraded(conf
);
7026 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
7027 print_raid5_conf(conf
);
7031 static int raid5_remove_disk(struct mddev
*mddev
, struct md_rdev
*rdev
)
7033 struct r5conf
*conf
= mddev
->private;
7035 int number
= rdev
->raid_disk
;
7036 struct md_rdev
**rdevp
;
7037 struct disk_info
*p
= conf
->disks
+ number
;
7039 print_raid5_conf(conf
);
7040 if (rdev
== p
->rdev
)
7042 else if (rdev
== p
->replacement
)
7043 rdevp
= &p
->replacement
;
7047 if (number
>= conf
->raid_disks
&&
7048 conf
->reshape_progress
== MaxSector
)
7049 clear_bit(In_sync
, &rdev
->flags
);
7051 if (test_bit(In_sync
, &rdev
->flags
) ||
7052 atomic_read(&rdev
->nr_pending
)) {
7056 /* Only remove non-faulty devices if recovery
7059 if (!test_bit(Faulty
, &rdev
->flags
) &&
7060 mddev
->recovery_disabled
!= conf
->recovery_disabled
&&
7061 !has_failed(conf
) &&
7062 (!p
->replacement
|| p
->replacement
== rdev
) &&
7063 number
< conf
->raid_disks
) {
7069 if (atomic_read(&rdev
->nr_pending
)) {
7070 /* lost the race, try later */
7073 } else if (p
->replacement
) {
7074 /* We must have just cleared 'rdev' */
7075 p
->rdev
= p
->replacement
;
7076 clear_bit(Replacement
, &p
->replacement
->flags
);
7077 smp_mb(); /* Make sure other CPUs may see both as identical
7078 * but will never see neither - if they are careful
7080 p
->replacement
= NULL
;
7081 clear_bit(WantReplacement
, &rdev
->flags
);
7083 /* We might have just removed the Replacement as faulty-
7084 * clear the bit just in case
7086 clear_bit(WantReplacement
, &rdev
->flags
);
7089 print_raid5_conf(conf
);
7093 static int raid5_add_disk(struct mddev
*mddev
, struct md_rdev
*rdev
)
7095 struct r5conf
*conf
= mddev
->private;
7098 struct disk_info
*p
;
7100 int last
= conf
->raid_disks
- 1;
7102 if (mddev
->recovery_disabled
== conf
->recovery_disabled
)
7105 if (rdev
->saved_raid_disk
< 0 && has_failed(conf
))
7106 /* no point adding a device */
7109 if (rdev
->raid_disk
>= 0)
7110 first
= last
= rdev
->raid_disk
;
7113 * find the disk ... but prefer rdev->saved_raid_disk
7116 if (rdev
->saved_raid_disk
>= 0 &&
7117 rdev
->saved_raid_disk
>= first
&&
7118 conf
->disks
[rdev
->saved_raid_disk
].rdev
== NULL
)
7119 first
= rdev
->saved_raid_disk
;
7121 for (disk
= first
; disk
<= last
; disk
++) {
7122 p
= conf
->disks
+ disk
;
7123 if (p
->rdev
== NULL
) {
7124 clear_bit(In_sync
, &rdev
->flags
);
7125 rdev
->raid_disk
= disk
;
7127 if (rdev
->saved_raid_disk
!= disk
)
7129 rcu_assign_pointer(p
->rdev
, rdev
);
7133 for (disk
= first
; disk
<= last
; disk
++) {
7134 p
= conf
->disks
+ disk
;
7135 if (test_bit(WantReplacement
, &p
->rdev
->flags
) &&
7136 p
->replacement
== NULL
) {
7137 clear_bit(In_sync
, &rdev
->flags
);
7138 set_bit(Replacement
, &rdev
->flags
);
7139 rdev
->raid_disk
= disk
;
7142 rcu_assign_pointer(p
->replacement
, rdev
);
7147 print_raid5_conf(conf
);
7151 static int raid5_resize(struct mddev
*mddev
, sector_t sectors
)
7153 /* no resync is happening, and there is enough space
7154 * on all devices, so we can resize.
7155 * We need to make sure resync covers any new space.
7156 * If the array is shrinking we should possibly wait until
7157 * any io in the removed space completes, but it hardly seems
7161 sectors
&= ~((sector_t
)mddev
->chunk_sectors
- 1);
7162 newsize
= raid5_size(mddev
, sectors
, mddev
->raid_disks
);
7163 if (mddev
->external_size
&&
7164 mddev
->array_sectors
> newsize
)
7166 if (mddev
->bitmap
) {
7167 int ret
= bitmap_resize(mddev
->bitmap
, sectors
, 0, 0);
7171 md_set_array_sectors(mddev
, newsize
);
7172 set_capacity(mddev
->gendisk
, mddev
->array_sectors
);
7173 revalidate_disk(mddev
->gendisk
);
7174 if (sectors
> mddev
->dev_sectors
&&
7175 mddev
->recovery_cp
> mddev
->dev_sectors
) {
7176 mddev
->recovery_cp
= mddev
->dev_sectors
;
7177 set_bit(MD_RECOVERY_NEEDED
, &mddev
->recovery
);
7179 mddev
->dev_sectors
= sectors
;
7180 mddev
->resync_max_sectors
= sectors
;
7184 static int check_stripe_cache(struct mddev
*mddev
)
7186 /* Can only proceed if there are plenty of stripe_heads.
7187 * We need a minimum of one full stripe,, and for sensible progress
7188 * it is best to have about 4 times that.
7189 * If we require 4 times, then the default 256 4K stripe_heads will
7190 * allow for chunk sizes up to 256K, which is probably OK.
7191 * If the chunk size is greater, user-space should request more
7192 * stripe_heads first.
7194 struct r5conf
*conf
= mddev
->private;
7195 if (((mddev
->chunk_sectors
<< 9) / STRIPE_SIZE
) * 4
7196 > conf
->min_nr_stripes
||
7197 ((mddev
->new_chunk_sectors
<< 9) / STRIPE_SIZE
) * 4
7198 > conf
->min_nr_stripes
) {
7199 printk(KERN_WARNING
"md/raid:%s: reshape: not enough stripes. Needed %lu\n",
7201 ((max(mddev
->chunk_sectors
, mddev
->new_chunk_sectors
) << 9)
7208 static int check_reshape(struct mddev
*mddev
)
7210 struct r5conf
*conf
= mddev
->private;
7212 if (mddev
->delta_disks
== 0 &&
7213 mddev
->new_layout
== mddev
->layout
&&
7214 mddev
->new_chunk_sectors
== mddev
->chunk_sectors
)
7215 return 0; /* nothing to do */
7216 if (has_failed(conf
))
7218 if (mddev
->delta_disks
< 0 && mddev
->reshape_position
== MaxSector
) {
7219 /* We might be able to shrink, but the devices must
7220 * be made bigger first.
7221 * For raid6, 4 is the minimum size.
7222 * Otherwise 2 is the minimum
7225 if (mddev
->level
== 6)
7227 if (mddev
->raid_disks
+ mddev
->delta_disks
< min
)
7231 if (!check_stripe_cache(mddev
))
7234 if (mddev
->new_chunk_sectors
> mddev
->chunk_sectors
||
7235 mddev
->delta_disks
> 0)
7236 if (resize_chunks(conf
,
7237 conf
->previous_raid_disks
7238 + max(0, mddev
->delta_disks
),
7239 max(mddev
->new_chunk_sectors
,
7240 mddev
->chunk_sectors
)
7243 return resize_stripes(conf
, (conf
->previous_raid_disks
7244 + mddev
->delta_disks
));
7247 static int raid5_start_reshape(struct mddev
*mddev
)
7249 struct r5conf
*conf
= mddev
->private;
7250 struct md_rdev
*rdev
;
7252 unsigned long flags
;
7254 if (test_bit(MD_RECOVERY_RUNNING
, &mddev
->recovery
))
7257 if (!check_stripe_cache(mddev
))
7260 if (has_failed(conf
))
7263 rdev_for_each(rdev
, mddev
) {
7264 if (!test_bit(In_sync
, &rdev
->flags
)
7265 && !test_bit(Faulty
, &rdev
->flags
))
7269 if (spares
- mddev
->degraded
< mddev
->delta_disks
- conf
->max_degraded
)
7270 /* Not enough devices even to make a degraded array
7275 /* Refuse to reduce size of the array. Any reductions in
7276 * array size must be through explicit setting of array_size
7279 if (raid5_size(mddev
, 0, conf
->raid_disks
+ mddev
->delta_disks
)
7280 < mddev
->array_sectors
) {
7281 printk(KERN_ERR
"md/raid:%s: array size must be reduced "
7282 "before number of disks\n", mdname(mddev
));
7286 atomic_set(&conf
->reshape_stripes
, 0);
7287 spin_lock_irq(&conf
->device_lock
);
7288 write_seqcount_begin(&conf
->gen_lock
);
7289 conf
->previous_raid_disks
= conf
->raid_disks
;
7290 conf
->raid_disks
+= mddev
->delta_disks
;
7291 conf
->prev_chunk_sectors
= conf
->chunk_sectors
;
7292 conf
->chunk_sectors
= mddev
->new_chunk_sectors
;
7293 conf
->prev_algo
= conf
->algorithm
;
7294 conf
->algorithm
= mddev
->new_layout
;
7296 /* Code that selects data_offset needs to see the generation update
7297 * if reshape_progress has been set - so a memory barrier needed.
7300 if (mddev
->reshape_backwards
)
7301 conf
->reshape_progress
= raid5_size(mddev
, 0, 0);
7303 conf
->reshape_progress
= 0;
7304 conf
->reshape_safe
= conf
->reshape_progress
;
7305 write_seqcount_end(&conf
->gen_lock
);
7306 spin_unlock_irq(&conf
->device_lock
);
7308 /* Now make sure any requests that proceeded on the assumption
7309 * the reshape wasn't running - like Discard or Read - have
7312 mddev_suspend(mddev
);
7313 mddev_resume(mddev
);
7315 /* Add some new drives, as many as will fit.
7316 * We know there are enough to make the newly sized array work.
7317 * Don't add devices if we are reducing the number of
7318 * devices in the array. This is because it is not possible
7319 * to correctly record the "partially reconstructed" state of
7320 * such devices during the reshape and confusion could result.
7322 if (mddev
->delta_disks
>= 0) {
7323 rdev_for_each(rdev
, mddev
)
7324 if (rdev
->raid_disk
< 0 &&
7325 !test_bit(Faulty
, &rdev
->flags
)) {
7326 if (raid5_add_disk(mddev
, rdev
) == 0) {
7328 >= conf
->previous_raid_disks
)
7329 set_bit(In_sync
, &rdev
->flags
);
7331 rdev
->recovery_offset
= 0;
7333 if (sysfs_link_rdev(mddev
, rdev
))
7334 /* Failure here is OK */;
7336 } else if (rdev
->raid_disk
>= conf
->previous_raid_disks
7337 && !test_bit(Faulty
, &rdev
->flags
)) {
7338 /* This is a spare that was manually added */
7339 set_bit(In_sync
, &rdev
->flags
);
7342 /* When a reshape changes the number of devices,
7343 * ->degraded is measured against the larger of the
7344 * pre and post number of devices.
7346 spin_lock_irqsave(&conf
->device_lock
, flags
);
7347 mddev
->degraded
= calc_degraded(conf
);
7348 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
7350 mddev
->raid_disks
= conf
->raid_disks
;
7351 mddev
->reshape_position
= conf
->reshape_progress
;
7352 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
7354 clear_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
);
7355 clear_bit(MD_RECOVERY_CHECK
, &mddev
->recovery
);
7356 set_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
);
7357 set_bit(MD_RECOVERY_RUNNING
, &mddev
->recovery
);
7358 mddev
->sync_thread
= md_register_thread(md_do_sync
, mddev
,
7360 if (!mddev
->sync_thread
) {
7361 mddev
->recovery
= 0;
7362 spin_lock_irq(&conf
->device_lock
);
7363 write_seqcount_begin(&conf
->gen_lock
);
7364 mddev
->raid_disks
= conf
->raid_disks
= conf
->previous_raid_disks
;
7365 mddev
->new_chunk_sectors
=
7366 conf
->chunk_sectors
= conf
->prev_chunk_sectors
;
7367 mddev
->new_layout
= conf
->algorithm
= conf
->prev_algo
;
7368 rdev_for_each(rdev
, mddev
)
7369 rdev
->new_data_offset
= rdev
->data_offset
;
7371 conf
->generation
--;
7372 conf
->reshape_progress
= MaxSector
;
7373 mddev
->reshape_position
= MaxSector
;
7374 write_seqcount_end(&conf
->gen_lock
);
7375 spin_unlock_irq(&conf
->device_lock
);
7378 conf
->reshape_checkpoint
= jiffies
;
7379 md_wakeup_thread(mddev
->sync_thread
);
7380 md_new_event(mddev
);
7384 /* This is called from the reshape thread and should make any
7385 * changes needed in 'conf'
7387 static void end_reshape(struct r5conf
*conf
)
7390 if (!test_bit(MD_RECOVERY_INTR
, &conf
->mddev
->recovery
)) {
7391 struct md_rdev
*rdev
;
7393 spin_lock_irq(&conf
->device_lock
);
7394 conf
->previous_raid_disks
= conf
->raid_disks
;
7395 rdev_for_each(rdev
, conf
->mddev
)
7396 rdev
->data_offset
= rdev
->new_data_offset
;
7398 conf
->reshape_progress
= MaxSector
;
7399 spin_unlock_irq(&conf
->device_lock
);
7400 wake_up(&conf
->wait_for_overlap
);
7402 /* read-ahead size must cover two whole stripes, which is
7403 * 2 * (datadisks) * chunksize where 'n' is the number of raid devices
7405 if (conf
->mddev
->queue
) {
7406 int data_disks
= conf
->raid_disks
- conf
->max_degraded
;
7407 int stripe
= data_disks
* ((conf
->chunk_sectors
<< 9)
7409 if (conf
->mddev
->queue
->backing_dev_info
.ra_pages
< 2 * stripe
)
7410 conf
->mddev
->queue
->backing_dev_info
.ra_pages
= 2 * stripe
;
7415 /* This is called from the raid5d thread with mddev_lock held.
7416 * It makes config changes to the device.
7418 static void raid5_finish_reshape(struct mddev
*mddev
)
7420 struct r5conf
*conf
= mddev
->private;
7422 if (!test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
)) {
7424 if (mddev
->delta_disks
> 0) {
7425 md_set_array_sectors(mddev
, raid5_size(mddev
, 0, 0));
7426 set_capacity(mddev
->gendisk
, mddev
->array_sectors
);
7427 revalidate_disk(mddev
->gendisk
);
7430 spin_lock_irq(&conf
->device_lock
);
7431 mddev
->degraded
= calc_degraded(conf
);
7432 spin_unlock_irq(&conf
->device_lock
);
7433 for (d
= conf
->raid_disks
;
7434 d
< conf
->raid_disks
- mddev
->delta_disks
;
7436 struct md_rdev
*rdev
= conf
->disks
[d
].rdev
;
7438 clear_bit(In_sync
, &rdev
->flags
);
7439 rdev
= conf
->disks
[d
].replacement
;
7441 clear_bit(In_sync
, &rdev
->flags
);
7444 mddev
->layout
= conf
->algorithm
;
7445 mddev
->chunk_sectors
= conf
->chunk_sectors
;
7446 mddev
->reshape_position
= MaxSector
;
7447 mddev
->delta_disks
= 0;
7448 mddev
->reshape_backwards
= 0;
7452 static void raid5_quiesce(struct mddev
*mddev
, int state
)
7454 struct r5conf
*conf
= mddev
->private;
7457 case 2: /* resume for a suspend */
7458 wake_up(&conf
->wait_for_overlap
);
7461 case 1: /* stop all writes */
7462 lock_all_device_hash_locks_irq(conf
);
7463 /* '2' tells resync/reshape to pause so that all
7464 * active stripes can drain
7467 wait_event_cmd(conf
->wait_for_stripe
,
7468 atomic_read(&conf
->active_stripes
) == 0 &&
7469 atomic_read(&conf
->active_aligned_reads
) == 0,
7470 unlock_all_device_hash_locks_irq(conf
),
7471 lock_all_device_hash_locks_irq(conf
));
7473 unlock_all_device_hash_locks_irq(conf
);
7474 /* allow reshape to continue */
7475 wake_up(&conf
->wait_for_overlap
);
7478 case 0: /* re-enable writes */
7479 lock_all_device_hash_locks_irq(conf
);
7481 wake_up(&conf
->wait_for_stripe
);
7482 wake_up(&conf
->wait_for_overlap
);
7483 unlock_all_device_hash_locks_irq(conf
);
7488 static void *raid45_takeover_raid0(struct mddev
*mddev
, int level
)
7490 struct r0conf
*raid0_conf
= mddev
->private;
7493 /* for raid0 takeover only one zone is supported */
7494 if (raid0_conf
->nr_strip_zones
> 1) {
7495 printk(KERN_ERR
"md/raid:%s: cannot takeover raid0 with more than one zone.\n",
7497 return ERR_PTR(-EINVAL
);
7500 sectors
= raid0_conf
->strip_zone
[0].zone_end
;
7501 sector_div(sectors
, raid0_conf
->strip_zone
[0].nb_dev
);
7502 mddev
->dev_sectors
= sectors
;
7503 mddev
->new_level
= level
;
7504 mddev
->new_layout
= ALGORITHM_PARITY_N
;
7505 mddev
->new_chunk_sectors
= mddev
->chunk_sectors
;
7506 mddev
->raid_disks
+= 1;
7507 mddev
->delta_disks
= 1;
7508 /* make sure it will be not marked as dirty */
7509 mddev
->recovery_cp
= MaxSector
;
7511 return setup_conf(mddev
);
7514 static void *raid5_takeover_raid1(struct mddev
*mddev
)
7518 if (mddev
->raid_disks
!= 2 ||
7519 mddev
->degraded
> 1)
7520 return ERR_PTR(-EINVAL
);
7522 /* Should check if there are write-behind devices? */
7524 chunksect
= 64*2; /* 64K by default */
7526 /* The array must be an exact multiple of chunksize */
7527 while (chunksect
&& (mddev
->array_sectors
& (chunksect
-1)))
7530 if ((chunksect
<<9) < STRIPE_SIZE
)
7531 /* array size does not allow a suitable chunk size */
7532 return ERR_PTR(-EINVAL
);
7534 mddev
->new_level
= 5;
7535 mddev
->new_layout
= ALGORITHM_LEFT_SYMMETRIC
;
7536 mddev
->new_chunk_sectors
= chunksect
;
7538 return setup_conf(mddev
);
7541 static void *raid5_takeover_raid6(struct mddev
*mddev
)
7545 switch (mddev
->layout
) {
7546 case ALGORITHM_LEFT_ASYMMETRIC_6
:
7547 new_layout
= ALGORITHM_LEFT_ASYMMETRIC
;
7549 case ALGORITHM_RIGHT_ASYMMETRIC_6
:
7550 new_layout
= ALGORITHM_RIGHT_ASYMMETRIC
;
7552 case ALGORITHM_LEFT_SYMMETRIC_6
:
7553 new_layout
= ALGORITHM_LEFT_SYMMETRIC
;
7555 case ALGORITHM_RIGHT_SYMMETRIC_6
:
7556 new_layout
= ALGORITHM_RIGHT_SYMMETRIC
;
7558 case ALGORITHM_PARITY_0_6
:
7559 new_layout
= ALGORITHM_PARITY_0
;
7561 case ALGORITHM_PARITY_N
:
7562 new_layout
= ALGORITHM_PARITY_N
;
7565 return ERR_PTR(-EINVAL
);
7567 mddev
->new_level
= 5;
7568 mddev
->new_layout
= new_layout
;
7569 mddev
->delta_disks
= -1;
7570 mddev
->raid_disks
-= 1;
7571 return setup_conf(mddev
);
7574 static int raid5_check_reshape(struct mddev
*mddev
)
7576 /* For a 2-drive array, the layout and chunk size can be changed
7577 * immediately as not restriping is needed.
7578 * For larger arrays we record the new value - after validation
7579 * to be used by a reshape pass.
7581 struct r5conf
*conf
= mddev
->private;
7582 int new_chunk
= mddev
->new_chunk_sectors
;
7584 if (mddev
->new_layout
>= 0 && !algorithm_valid_raid5(mddev
->new_layout
))
7586 if (new_chunk
> 0) {
7587 if (!is_power_of_2(new_chunk
))
7589 if (new_chunk
< (PAGE_SIZE
>>9))
7591 if (mddev
->array_sectors
& (new_chunk
-1))
7592 /* not factor of array size */
7596 /* They look valid */
7598 if (mddev
->raid_disks
== 2) {
7599 /* can make the change immediately */
7600 if (mddev
->new_layout
>= 0) {
7601 conf
->algorithm
= mddev
->new_layout
;
7602 mddev
->layout
= mddev
->new_layout
;
7604 if (new_chunk
> 0) {
7605 conf
->chunk_sectors
= new_chunk
;
7606 mddev
->chunk_sectors
= new_chunk
;
7608 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
7609 md_wakeup_thread(mddev
->thread
);
7611 return check_reshape(mddev
);
7614 static int raid6_check_reshape(struct mddev
*mddev
)
7616 int new_chunk
= mddev
->new_chunk_sectors
;
7618 if (mddev
->new_layout
>= 0 && !algorithm_valid_raid6(mddev
->new_layout
))
7620 if (new_chunk
> 0) {
7621 if (!is_power_of_2(new_chunk
))
7623 if (new_chunk
< (PAGE_SIZE
>> 9))
7625 if (mddev
->array_sectors
& (new_chunk
-1))
7626 /* not factor of array size */
7630 /* They look valid */
7631 return check_reshape(mddev
);
7634 static void *raid5_takeover(struct mddev
*mddev
)
7636 /* raid5 can take over:
7637 * raid0 - if there is only one strip zone - make it a raid4 layout
7638 * raid1 - if there are two drives. We need to know the chunk size
7639 * raid4 - trivial - just use a raid4 layout.
7640 * raid6 - Providing it is a *_6 layout
7642 if (mddev
->level
== 0)
7643 return raid45_takeover_raid0(mddev
, 5);
7644 if (mddev
->level
== 1)
7645 return raid5_takeover_raid1(mddev
);
7646 if (mddev
->level
== 4) {
7647 mddev
->new_layout
= ALGORITHM_PARITY_N
;
7648 mddev
->new_level
= 5;
7649 return setup_conf(mddev
);
7651 if (mddev
->level
== 6)
7652 return raid5_takeover_raid6(mddev
);
7654 return ERR_PTR(-EINVAL
);
7657 static void *raid4_takeover(struct mddev
*mddev
)
7659 /* raid4 can take over:
7660 * raid0 - if there is only one strip zone
7661 * raid5 - if layout is right
7663 if (mddev
->level
== 0)
7664 return raid45_takeover_raid0(mddev
, 4);
7665 if (mddev
->level
== 5 &&
7666 mddev
->layout
== ALGORITHM_PARITY_N
) {
7667 mddev
->new_layout
= 0;
7668 mddev
->new_level
= 4;
7669 return setup_conf(mddev
);
7671 return ERR_PTR(-EINVAL
);
7674 static struct md_personality raid5_personality
;
7676 static void *raid6_takeover(struct mddev
*mddev
)
7678 /* Currently can only take over a raid5. We map the
7679 * personality to an equivalent raid6 personality
7680 * with the Q block at the end.
7684 if (mddev
->pers
!= &raid5_personality
)
7685 return ERR_PTR(-EINVAL
);
7686 if (mddev
->degraded
> 1)
7687 return ERR_PTR(-EINVAL
);
7688 if (mddev
->raid_disks
> 253)
7689 return ERR_PTR(-EINVAL
);
7690 if (mddev
->raid_disks
< 3)
7691 return ERR_PTR(-EINVAL
);
7693 switch (mddev
->layout
) {
7694 case ALGORITHM_LEFT_ASYMMETRIC
:
7695 new_layout
= ALGORITHM_LEFT_ASYMMETRIC_6
;
7697 case ALGORITHM_RIGHT_ASYMMETRIC
:
7698 new_layout
= ALGORITHM_RIGHT_ASYMMETRIC_6
;
7700 case ALGORITHM_LEFT_SYMMETRIC
:
7701 new_layout
= ALGORITHM_LEFT_SYMMETRIC_6
;
7703 case ALGORITHM_RIGHT_SYMMETRIC
:
7704 new_layout
= ALGORITHM_RIGHT_SYMMETRIC_6
;
7706 case ALGORITHM_PARITY_0
:
7707 new_layout
= ALGORITHM_PARITY_0_6
;
7709 case ALGORITHM_PARITY_N
:
7710 new_layout
= ALGORITHM_PARITY_N
;
7713 return ERR_PTR(-EINVAL
);
7715 mddev
->new_level
= 6;
7716 mddev
->new_layout
= new_layout
;
7717 mddev
->delta_disks
= 1;
7718 mddev
->raid_disks
+= 1;
7719 return setup_conf(mddev
);
7722 static struct md_personality raid6_personality
=
7726 .owner
= THIS_MODULE
,
7727 .make_request
= make_request
,
7731 .error_handler
= error
,
7732 .hot_add_disk
= raid5_add_disk
,
7733 .hot_remove_disk
= raid5_remove_disk
,
7734 .spare_active
= raid5_spare_active
,
7735 .sync_request
= sync_request
,
7736 .resize
= raid5_resize
,
7738 .check_reshape
= raid6_check_reshape
,
7739 .start_reshape
= raid5_start_reshape
,
7740 .finish_reshape
= raid5_finish_reshape
,
7741 .quiesce
= raid5_quiesce
,
7742 .takeover
= raid6_takeover
,
7743 .congested
= raid5_congested
,
7744 .mergeable_bvec
= raid5_mergeable_bvec
,
7746 static struct md_personality raid5_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
= raid5_takeover
,
7767 .congested
= raid5_congested
,
7768 .mergeable_bvec
= raid5_mergeable_bvec
,
7771 static struct md_personality raid4_personality
=
7775 .owner
= THIS_MODULE
,
7776 .make_request
= make_request
,
7780 .error_handler
= error
,
7781 .hot_add_disk
= raid5_add_disk
,
7782 .hot_remove_disk
= raid5_remove_disk
,
7783 .spare_active
= raid5_spare_active
,
7784 .sync_request
= sync_request
,
7785 .resize
= raid5_resize
,
7787 .check_reshape
= raid5_check_reshape
,
7788 .start_reshape
= raid5_start_reshape
,
7789 .finish_reshape
= raid5_finish_reshape
,
7790 .quiesce
= raid5_quiesce
,
7791 .takeover
= raid4_takeover
,
7792 .congested
= raid5_congested
,
7793 .mergeable_bvec
= raid5_mergeable_bvec
,
7796 static int __init
raid5_init(void)
7798 raid5_wq
= alloc_workqueue("raid5wq",
7799 WQ_UNBOUND
|WQ_MEM_RECLAIM
|WQ_CPU_INTENSIVE
|WQ_SYSFS
, 0);
7802 register_md_personality(&raid6_personality
);
7803 register_md_personality(&raid5_personality
);
7804 register_md_personality(&raid4_personality
);
7808 static void raid5_exit(void)
7810 unregister_md_personality(&raid6_personality
);
7811 unregister_md_personality(&raid5_personality
);
7812 unregister_md_personality(&raid4_personality
);
7813 destroy_workqueue(raid5_wq
);
7816 module_init(raid5_init
);
7817 module_exit(raid5_exit
);
7818 MODULE_LICENSE("GPL");
7819 MODULE_DESCRIPTION("RAID4/5/6 (striping with parity) personality for MD");
7820 MODULE_ALIAS("md-personality-4"); /* RAID5 */
7821 MODULE_ALIAS("md-raid5");
7822 MODULE_ALIAS("md-raid4");
7823 MODULE_ALIAS("md-level-5");
7824 MODULE_ALIAS("md-level-4");
7825 MODULE_ALIAS("md-personality-8"); /* RAID6 */
7826 MODULE_ALIAS("md-raid6");
7827 MODULE_ALIAS("md-level-6");
7829 /* This used to be two separate modules, they were: */
7830 MODULE_ALIAS("raid5");
7831 MODULE_ALIAS("raid6");