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_list
*return_bi
)
229 while ((bi
= bio_list_pop(return_bi
)) != NULL
) {
230 bi
->bi_iter
.bi_size
= 0;
231 trace_block_bio_complete(bdev_get_queue(bi
->bi_bdev
),
237 static void print_raid5_conf (struct r5conf
*conf
);
239 static int stripe_operations_active(struct stripe_head
*sh
)
241 return sh
->check_state
|| sh
->reconstruct_state
||
242 test_bit(STRIPE_BIOFILL_RUN
, &sh
->state
) ||
243 test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
246 static void raid5_wakeup_stripe_thread(struct stripe_head
*sh
)
248 struct r5conf
*conf
= sh
->raid_conf
;
249 struct r5worker_group
*group
;
251 int i
, cpu
= sh
->cpu
;
253 if (!cpu_online(cpu
)) {
254 cpu
= cpumask_any(cpu_online_mask
);
258 if (list_empty(&sh
->lru
)) {
259 struct r5worker_group
*group
;
260 group
= conf
->worker_groups
+ cpu_to_group(cpu
);
261 list_add_tail(&sh
->lru
, &group
->handle_list
);
262 group
->stripes_cnt
++;
266 if (conf
->worker_cnt_per_group
== 0) {
267 md_wakeup_thread(conf
->mddev
->thread
);
271 group
= conf
->worker_groups
+ cpu_to_group(sh
->cpu
);
273 group
->workers
[0].working
= true;
274 /* at least one worker should run to avoid race */
275 queue_work_on(sh
->cpu
, raid5_wq
, &group
->workers
[0].work
);
277 thread_cnt
= group
->stripes_cnt
/ MAX_STRIPE_BATCH
- 1;
278 /* wakeup more workers */
279 for (i
= 1; i
< conf
->worker_cnt_per_group
&& thread_cnt
> 0; i
++) {
280 if (group
->workers
[i
].working
== false) {
281 group
->workers
[i
].working
= true;
282 queue_work_on(sh
->cpu
, raid5_wq
,
283 &group
->workers
[i
].work
);
289 static void do_release_stripe(struct r5conf
*conf
, struct stripe_head
*sh
,
290 struct list_head
*temp_inactive_list
)
292 BUG_ON(!list_empty(&sh
->lru
));
293 BUG_ON(atomic_read(&conf
->active_stripes
)==0);
294 if (test_bit(STRIPE_HANDLE
, &sh
->state
)) {
295 if (test_bit(STRIPE_DELAYED
, &sh
->state
) &&
296 !test_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
297 list_add_tail(&sh
->lru
, &conf
->delayed_list
);
298 else if (test_bit(STRIPE_BIT_DELAY
, &sh
->state
) &&
299 sh
->bm_seq
- conf
->seq_write
> 0)
300 list_add_tail(&sh
->lru
, &conf
->bitmap_list
);
302 clear_bit(STRIPE_DELAYED
, &sh
->state
);
303 clear_bit(STRIPE_BIT_DELAY
, &sh
->state
);
304 if (conf
->worker_cnt_per_group
== 0) {
305 list_add_tail(&sh
->lru
, &conf
->handle_list
);
307 raid5_wakeup_stripe_thread(sh
);
311 md_wakeup_thread(conf
->mddev
->thread
);
313 BUG_ON(stripe_operations_active(sh
));
314 if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
315 if (atomic_dec_return(&conf
->preread_active_stripes
)
317 md_wakeup_thread(conf
->mddev
->thread
);
318 atomic_dec(&conf
->active_stripes
);
319 if (!test_bit(STRIPE_EXPANDING
, &sh
->state
))
320 list_add_tail(&sh
->lru
, temp_inactive_list
);
324 static void __release_stripe(struct r5conf
*conf
, struct stripe_head
*sh
,
325 struct list_head
*temp_inactive_list
)
327 if (atomic_dec_and_test(&sh
->count
))
328 do_release_stripe(conf
, sh
, temp_inactive_list
);
332 * @hash could be NR_STRIPE_HASH_LOCKS, then we have a list of inactive_list
334 * Be careful: Only one task can add/delete stripes from temp_inactive_list at
335 * given time. Adding stripes only takes device lock, while deleting stripes
336 * only takes hash lock.
338 static void release_inactive_stripe_list(struct r5conf
*conf
,
339 struct list_head
*temp_inactive_list
,
343 bool do_wakeup
= false;
346 if (hash
== NR_STRIPE_HASH_LOCKS
) {
347 size
= NR_STRIPE_HASH_LOCKS
;
348 hash
= NR_STRIPE_HASH_LOCKS
- 1;
352 struct list_head
*list
= &temp_inactive_list
[size
- 1];
355 * We don't hold any lock here yet, raid5_get_active_stripe() might
356 * remove stripes from the list
358 if (!list_empty_careful(list
)) {
359 spin_lock_irqsave(conf
->hash_locks
+ hash
, flags
);
360 if (list_empty(conf
->inactive_list
+ hash
) &&
362 atomic_dec(&conf
->empty_inactive_list_nr
);
363 list_splice_tail_init(list
, conf
->inactive_list
+ hash
);
365 spin_unlock_irqrestore(conf
->hash_locks
+ hash
, flags
);
372 wake_up(&conf
->wait_for_stripe
);
373 if (atomic_read(&conf
->active_stripes
) == 0)
374 wake_up(&conf
->wait_for_quiescent
);
375 if (conf
->retry_read_aligned
)
376 md_wakeup_thread(conf
->mddev
->thread
);
380 /* should hold conf->device_lock already */
381 static int release_stripe_list(struct r5conf
*conf
,
382 struct list_head
*temp_inactive_list
)
384 struct stripe_head
*sh
;
386 struct llist_node
*head
;
388 head
= llist_del_all(&conf
->released_stripes
);
389 head
= llist_reverse_order(head
);
393 sh
= llist_entry(head
, struct stripe_head
, release_list
);
394 head
= llist_next(head
);
395 /* sh could be readded after STRIPE_ON_RELEASE_LIST is cleard */
397 clear_bit(STRIPE_ON_RELEASE_LIST
, &sh
->state
);
399 * Don't worry the bit is set here, because if the bit is set
400 * again, the count is always > 1. This is true for
401 * STRIPE_ON_UNPLUG_LIST bit too.
403 hash
= sh
->hash_lock_index
;
404 __release_stripe(conf
, sh
, &temp_inactive_list
[hash
]);
411 void raid5_release_stripe(struct stripe_head
*sh
)
413 struct r5conf
*conf
= sh
->raid_conf
;
415 struct list_head list
;
419 /* Avoid release_list until the last reference.
421 if (atomic_add_unless(&sh
->count
, -1, 1))
424 if (unlikely(!conf
->mddev
->thread
) ||
425 test_and_set_bit(STRIPE_ON_RELEASE_LIST
, &sh
->state
))
427 wakeup
= llist_add(&sh
->release_list
, &conf
->released_stripes
);
429 md_wakeup_thread(conf
->mddev
->thread
);
432 local_irq_save(flags
);
433 /* we are ok here if STRIPE_ON_RELEASE_LIST is set or not */
434 if (atomic_dec_and_lock(&sh
->count
, &conf
->device_lock
)) {
435 INIT_LIST_HEAD(&list
);
436 hash
= sh
->hash_lock_index
;
437 do_release_stripe(conf
, sh
, &list
);
438 spin_unlock(&conf
->device_lock
);
439 release_inactive_stripe_list(conf
, &list
, hash
);
441 local_irq_restore(flags
);
444 static inline void remove_hash(struct stripe_head
*sh
)
446 pr_debug("remove_hash(), stripe %llu\n",
447 (unsigned long long)sh
->sector
);
449 hlist_del_init(&sh
->hash
);
452 static inline void insert_hash(struct r5conf
*conf
, struct stripe_head
*sh
)
454 struct hlist_head
*hp
= stripe_hash(conf
, sh
->sector
);
456 pr_debug("insert_hash(), stripe %llu\n",
457 (unsigned long long)sh
->sector
);
459 hlist_add_head(&sh
->hash
, hp
);
462 /* find an idle stripe, make sure it is unhashed, and return it. */
463 static struct stripe_head
*get_free_stripe(struct r5conf
*conf
, int hash
)
465 struct stripe_head
*sh
= NULL
;
466 struct list_head
*first
;
468 if (list_empty(conf
->inactive_list
+ hash
))
470 first
= (conf
->inactive_list
+ hash
)->next
;
471 sh
= list_entry(first
, struct stripe_head
, lru
);
472 list_del_init(first
);
474 atomic_inc(&conf
->active_stripes
);
475 BUG_ON(hash
!= sh
->hash_lock_index
);
476 if (list_empty(conf
->inactive_list
+ hash
))
477 atomic_inc(&conf
->empty_inactive_list_nr
);
482 static void shrink_buffers(struct stripe_head
*sh
)
486 int num
= sh
->raid_conf
->pool_size
;
488 for (i
= 0; i
< num
; i
++) {
489 WARN_ON(sh
->dev
[i
].page
!= sh
->dev
[i
].orig_page
);
493 sh
->dev
[i
].page
= NULL
;
498 static int grow_buffers(struct stripe_head
*sh
, gfp_t gfp
)
501 int num
= sh
->raid_conf
->pool_size
;
503 for (i
= 0; i
< num
; i
++) {
506 if (!(page
= alloc_page(gfp
))) {
509 sh
->dev
[i
].page
= page
;
510 sh
->dev
[i
].orig_page
= page
;
515 static void raid5_build_block(struct stripe_head
*sh
, int i
, int previous
);
516 static void stripe_set_idx(sector_t stripe
, struct r5conf
*conf
, int previous
,
517 struct stripe_head
*sh
);
519 static void init_stripe(struct stripe_head
*sh
, sector_t sector
, int previous
)
521 struct r5conf
*conf
= sh
->raid_conf
;
524 BUG_ON(atomic_read(&sh
->count
) != 0);
525 BUG_ON(test_bit(STRIPE_HANDLE
, &sh
->state
));
526 BUG_ON(stripe_operations_active(sh
));
527 BUG_ON(sh
->batch_head
);
529 pr_debug("init_stripe called, stripe %llu\n",
530 (unsigned long long)sector
);
532 seq
= read_seqcount_begin(&conf
->gen_lock
);
533 sh
->generation
= conf
->generation
- previous
;
534 sh
->disks
= previous
? conf
->previous_raid_disks
: conf
->raid_disks
;
536 stripe_set_idx(sector
, conf
, previous
, sh
);
539 for (i
= sh
->disks
; i
--; ) {
540 struct r5dev
*dev
= &sh
->dev
[i
];
542 if (dev
->toread
|| dev
->read
|| dev
->towrite
|| dev
->written
||
543 test_bit(R5_LOCKED
, &dev
->flags
)) {
544 printk(KERN_ERR
"sector=%llx i=%d %p %p %p %p %d\n",
545 (unsigned long long)sh
->sector
, i
, dev
->toread
,
546 dev
->read
, dev
->towrite
, dev
->written
,
547 test_bit(R5_LOCKED
, &dev
->flags
));
551 raid5_build_block(sh
, i
, previous
);
553 if (read_seqcount_retry(&conf
->gen_lock
, seq
))
555 sh
->overwrite_disks
= 0;
556 insert_hash(conf
, sh
);
557 sh
->cpu
= smp_processor_id();
558 set_bit(STRIPE_BATCH_READY
, &sh
->state
);
561 static struct stripe_head
*__find_stripe(struct r5conf
*conf
, sector_t sector
,
564 struct stripe_head
*sh
;
566 pr_debug("__find_stripe, sector %llu\n", (unsigned long long)sector
);
567 hlist_for_each_entry(sh
, stripe_hash(conf
, sector
), hash
)
568 if (sh
->sector
== sector
&& sh
->generation
== generation
)
570 pr_debug("__stripe %llu not in cache\n", (unsigned long long)sector
);
575 * Need to check if array has failed when deciding whether to:
577 * - remove non-faulty devices
580 * This determination is simple when no reshape is happening.
581 * However if there is a reshape, we need to carefully check
582 * both the before and after sections.
583 * This is because some failed devices may only affect one
584 * of the two sections, and some non-in_sync devices may
585 * be insync in the section most affected by failed devices.
587 static int calc_degraded(struct r5conf
*conf
)
589 int degraded
, degraded2
;
594 for (i
= 0; i
< conf
->previous_raid_disks
; i
++) {
595 struct md_rdev
*rdev
= rcu_dereference(conf
->disks
[i
].rdev
);
596 if (rdev
&& test_bit(Faulty
, &rdev
->flags
))
597 rdev
= rcu_dereference(conf
->disks
[i
].replacement
);
598 if (!rdev
|| test_bit(Faulty
, &rdev
->flags
))
600 else if (test_bit(In_sync
, &rdev
->flags
))
603 /* not in-sync or faulty.
604 * If the reshape increases the number of devices,
605 * this is being recovered by the reshape, so
606 * this 'previous' section is not in_sync.
607 * If the number of devices is being reduced however,
608 * the device can only be part of the array if
609 * we are reverting a reshape, so this section will
612 if (conf
->raid_disks
>= conf
->previous_raid_disks
)
616 if (conf
->raid_disks
== conf
->previous_raid_disks
)
620 for (i
= 0; i
< conf
->raid_disks
; i
++) {
621 struct md_rdev
*rdev
= rcu_dereference(conf
->disks
[i
].rdev
);
622 if (rdev
&& test_bit(Faulty
, &rdev
->flags
))
623 rdev
= rcu_dereference(conf
->disks
[i
].replacement
);
624 if (!rdev
|| test_bit(Faulty
, &rdev
->flags
))
626 else if (test_bit(In_sync
, &rdev
->flags
))
629 /* not in-sync or faulty.
630 * If reshape increases the number of devices, this
631 * section has already been recovered, else it
632 * almost certainly hasn't.
634 if (conf
->raid_disks
<= conf
->previous_raid_disks
)
638 if (degraded2
> degraded
)
643 static int has_failed(struct r5conf
*conf
)
647 if (conf
->mddev
->reshape_position
== MaxSector
)
648 return conf
->mddev
->degraded
> conf
->max_degraded
;
650 degraded
= calc_degraded(conf
);
651 if (degraded
> conf
->max_degraded
)
657 raid5_get_active_stripe(struct r5conf
*conf
, sector_t sector
,
658 int previous
, int noblock
, int noquiesce
)
660 struct stripe_head
*sh
;
661 int hash
= stripe_hash_locks_hash(sector
);
663 pr_debug("get_stripe, sector %llu\n", (unsigned long long)sector
);
665 spin_lock_irq(conf
->hash_locks
+ hash
);
668 wait_event_lock_irq(conf
->wait_for_quiescent
,
669 conf
->quiesce
== 0 || noquiesce
,
670 *(conf
->hash_locks
+ hash
));
671 sh
= __find_stripe(conf
, sector
, conf
->generation
- previous
);
673 if (!test_bit(R5_INACTIVE_BLOCKED
, &conf
->cache_state
)) {
674 sh
= get_free_stripe(conf
, hash
);
675 if (!sh
&& !test_bit(R5_DID_ALLOC
,
677 set_bit(R5_ALLOC_MORE
,
680 if (noblock
&& sh
== NULL
)
683 set_bit(R5_INACTIVE_BLOCKED
,
686 conf
->wait_for_stripe
,
687 !list_empty(conf
->inactive_list
+ hash
) &&
688 (atomic_read(&conf
->active_stripes
)
689 < (conf
->max_nr_stripes
* 3 / 4)
690 || !test_bit(R5_INACTIVE_BLOCKED
,
691 &conf
->cache_state
)),
692 *(conf
->hash_locks
+ hash
));
693 clear_bit(R5_INACTIVE_BLOCKED
,
696 init_stripe(sh
, sector
, previous
);
697 atomic_inc(&sh
->count
);
699 } else if (!atomic_inc_not_zero(&sh
->count
)) {
700 spin_lock(&conf
->device_lock
);
701 if (!atomic_read(&sh
->count
)) {
702 if (!test_bit(STRIPE_HANDLE
, &sh
->state
))
703 atomic_inc(&conf
->active_stripes
);
704 BUG_ON(list_empty(&sh
->lru
) &&
705 !test_bit(STRIPE_EXPANDING
, &sh
->state
));
706 list_del_init(&sh
->lru
);
708 sh
->group
->stripes_cnt
--;
712 atomic_inc(&sh
->count
);
713 spin_unlock(&conf
->device_lock
);
715 } while (sh
== NULL
);
717 spin_unlock_irq(conf
->hash_locks
+ hash
);
721 static bool is_full_stripe_write(struct stripe_head
*sh
)
723 BUG_ON(sh
->overwrite_disks
> (sh
->disks
- sh
->raid_conf
->max_degraded
));
724 return sh
->overwrite_disks
== (sh
->disks
- sh
->raid_conf
->max_degraded
);
727 static void lock_two_stripes(struct stripe_head
*sh1
, struct stripe_head
*sh2
)
731 spin_lock(&sh2
->stripe_lock
);
732 spin_lock_nested(&sh1
->stripe_lock
, 1);
734 spin_lock(&sh1
->stripe_lock
);
735 spin_lock_nested(&sh2
->stripe_lock
, 1);
739 static void unlock_two_stripes(struct stripe_head
*sh1
, struct stripe_head
*sh2
)
741 spin_unlock(&sh1
->stripe_lock
);
742 spin_unlock(&sh2
->stripe_lock
);
746 /* Only freshly new full stripe normal write stripe can be added to a batch list */
747 static bool stripe_can_batch(struct stripe_head
*sh
)
749 struct r5conf
*conf
= sh
->raid_conf
;
753 return test_bit(STRIPE_BATCH_READY
, &sh
->state
) &&
754 !test_bit(STRIPE_BITMAP_PENDING
, &sh
->state
) &&
755 is_full_stripe_write(sh
);
758 /* we only do back search */
759 static void stripe_add_to_batch_list(struct r5conf
*conf
, struct stripe_head
*sh
)
761 struct stripe_head
*head
;
762 sector_t head_sector
, tmp_sec
;
766 if (!stripe_can_batch(sh
))
768 /* Don't cross chunks, so stripe pd_idx/qd_idx is the same */
769 tmp_sec
= sh
->sector
;
770 if (!sector_div(tmp_sec
, conf
->chunk_sectors
))
772 head_sector
= sh
->sector
- STRIPE_SECTORS
;
774 hash
= stripe_hash_locks_hash(head_sector
);
775 spin_lock_irq(conf
->hash_locks
+ hash
);
776 head
= __find_stripe(conf
, head_sector
, conf
->generation
);
777 if (head
&& !atomic_inc_not_zero(&head
->count
)) {
778 spin_lock(&conf
->device_lock
);
779 if (!atomic_read(&head
->count
)) {
780 if (!test_bit(STRIPE_HANDLE
, &head
->state
))
781 atomic_inc(&conf
->active_stripes
);
782 BUG_ON(list_empty(&head
->lru
) &&
783 !test_bit(STRIPE_EXPANDING
, &head
->state
));
784 list_del_init(&head
->lru
);
786 head
->group
->stripes_cnt
--;
790 atomic_inc(&head
->count
);
791 spin_unlock(&conf
->device_lock
);
793 spin_unlock_irq(conf
->hash_locks
+ hash
);
797 if (!stripe_can_batch(head
))
800 lock_two_stripes(head
, sh
);
801 /* clear_batch_ready clear the flag */
802 if (!stripe_can_batch(head
) || !stripe_can_batch(sh
))
809 while (dd_idx
== sh
->pd_idx
|| dd_idx
== sh
->qd_idx
)
811 if (head
->dev
[dd_idx
].towrite
->bi_rw
!= sh
->dev
[dd_idx
].towrite
->bi_rw
)
814 if (head
->batch_head
) {
815 spin_lock(&head
->batch_head
->batch_lock
);
816 /* This batch list is already running */
817 if (!stripe_can_batch(head
)) {
818 spin_unlock(&head
->batch_head
->batch_lock
);
823 * at this point, head's BATCH_READY could be cleared, but we
824 * can still add the stripe to batch list
826 list_add(&sh
->batch_list
, &head
->batch_list
);
827 spin_unlock(&head
->batch_head
->batch_lock
);
829 sh
->batch_head
= head
->batch_head
;
831 head
->batch_head
= head
;
832 sh
->batch_head
= head
->batch_head
;
833 spin_lock(&head
->batch_lock
);
834 list_add_tail(&sh
->batch_list
, &head
->batch_list
);
835 spin_unlock(&head
->batch_lock
);
838 if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
839 if (atomic_dec_return(&conf
->preread_active_stripes
)
841 md_wakeup_thread(conf
->mddev
->thread
);
843 if (test_and_clear_bit(STRIPE_BIT_DELAY
, &sh
->state
)) {
844 int seq
= sh
->bm_seq
;
845 if (test_bit(STRIPE_BIT_DELAY
, &sh
->batch_head
->state
) &&
846 sh
->batch_head
->bm_seq
> seq
)
847 seq
= sh
->batch_head
->bm_seq
;
848 set_bit(STRIPE_BIT_DELAY
, &sh
->batch_head
->state
);
849 sh
->batch_head
->bm_seq
= seq
;
852 atomic_inc(&sh
->count
);
854 unlock_two_stripes(head
, sh
);
856 raid5_release_stripe(head
);
859 /* Determine if 'data_offset' or 'new_data_offset' should be used
860 * in this stripe_head.
862 static int use_new_offset(struct r5conf
*conf
, struct stripe_head
*sh
)
864 sector_t progress
= conf
->reshape_progress
;
865 /* Need a memory barrier to make sure we see the value
866 * of conf->generation, or ->data_offset that was set before
867 * reshape_progress was updated.
870 if (progress
== MaxSector
)
872 if (sh
->generation
== conf
->generation
- 1)
874 /* We are in a reshape, and this is a new-generation stripe,
875 * so use new_data_offset.
881 raid5_end_read_request(struct bio
*bi
);
883 raid5_end_write_request(struct bio
*bi
);
885 static void ops_run_io(struct stripe_head
*sh
, struct stripe_head_state
*s
)
887 struct r5conf
*conf
= sh
->raid_conf
;
888 int i
, disks
= sh
->disks
;
889 struct stripe_head
*head_sh
= sh
;
893 if (r5l_write_stripe(conf
->log
, sh
) == 0)
895 for (i
= disks
; i
--; ) {
897 int replace_only
= 0;
898 struct bio
*bi
, *rbi
;
899 struct md_rdev
*rdev
, *rrdev
= NULL
;
902 if (test_and_clear_bit(R5_Wantwrite
, &sh
->dev
[i
].flags
)) {
903 if (test_and_clear_bit(R5_WantFUA
, &sh
->dev
[i
].flags
))
907 if (test_bit(R5_Discard
, &sh
->dev
[i
].flags
))
909 } else if (test_and_clear_bit(R5_Wantread
, &sh
->dev
[i
].flags
))
911 else if (test_and_clear_bit(R5_WantReplace
,
912 &sh
->dev
[i
].flags
)) {
917 if (test_and_clear_bit(R5_SyncIO
, &sh
->dev
[i
].flags
))
921 bi
= &sh
->dev
[i
].req
;
922 rbi
= &sh
->dev
[i
].rreq
; /* For writing to replacement */
925 rrdev
= rcu_dereference(conf
->disks
[i
].replacement
);
926 smp_mb(); /* Ensure that if rrdev is NULL, rdev won't be */
927 rdev
= rcu_dereference(conf
->disks
[i
].rdev
);
936 /* We raced and saw duplicates */
939 if (test_bit(R5_ReadRepl
, &head_sh
->dev
[i
].flags
) && rrdev
)
944 if (rdev
&& test_bit(Faulty
, &rdev
->flags
))
947 atomic_inc(&rdev
->nr_pending
);
948 if (rrdev
&& test_bit(Faulty
, &rrdev
->flags
))
951 atomic_inc(&rrdev
->nr_pending
);
954 /* We have already checked bad blocks for reads. Now
955 * need to check for writes. We never accept write errors
956 * on the replacement, so we don't to check rrdev.
958 while ((rw
& WRITE
) && rdev
&&
959 test_bit(WriteErrorSeen
, &rdev
->flags
)) {
962 int bad
= is_badblock(rdev
, sh
->sector
, STRIPE_SECTORS
,
963 &first_bad
, &bad_sectors
);
968 set_bit(BlockedBadBlocks
, &rdev
->flags
);
969 if (!conf
->mddev
->external
&&
970 conf
->mddev
->flags
) {
971 /* It is very unlikely, but we might
972 * still need to write out the
973 * bad block log - better give it
975 md_check_recovery(conf
->mddev
);
978 * Because md_wait_for_blocked_rdev
979 * will dec nr_pending, we must
980 * increment it first.
982 atomic_inc(&rdev
->nr_pending
);
983 md_wait_for_blocked_rdev(rdev
, conf
->mddev
);
985 /* Acknowledged bad block - skip the write */
986 rdev_dec_pending(rdev
, conf
->mddev
);
992 if (s
->syncing
|| s
->expanding
|| s
->expanded
994 md_sync_acct(rdev
->bdev
, STRIPE_SECTORS
);
996 set_bit(STRIPE_IO_STARTED
, &sh
->state
);
999 bi
->bi_bdev
= rdev
->bdev
;
1001 bi
->bi_end_io
= (rw
& WRITE
)
1002 ? raid5_end_write_request
1003 : raid5_end_read_request
;
1004 bi
->bi_private
= sh
;
1006 pr_debug("%s: for %llu schedule op %ld on disc %d\n",
1007 __func__
, (unsigned long long)sh
->sector
,
1009 atomic_inc(&sh
->count
);
1011 atomic_inc(&head_sh
->count
);
1012 if (use_new_offset(conf
, sh
))
1013 bi
->bi_iter
.bi_sector
= (sh
->sector
1014 + rdev
->new_data_offset
);
1016 bi
->bi_iter
.bi_sector
= (sh
->sector
1017 + rdev
->data_offset
);
1018 if (test_bit(R5_ReadNoMerge
, &head_sh
->dev
[i
].flags
))
1019 bi
->bi_rw
|= REQ_NOMERGE
;
1021 if (test_bit(R5_SkipCopy
, &sh
->dev
[i
].flags
))
1022 WARN_ON(test_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
));
1023 sh
->dev
[i
].vec
.bv_page
= sh
->dev
[i
].page
;
1025 bi
->bi_io_vec
[0].bv_len
= STRIPE_SIZE
;
1026 bi
->bi_io_vec
[0].bv_offset
= 0;
1027 bi
->bi_iter
.bi_size
= STRIPE_SIZE
;
1029 * If this is discard request, set bi_vcnt 0. We don't
1030 * want to confuse SCSI because SCSI will replace payload
1032 if (rw
& REQ_DISCARD
)
1035 set_bit(R5_DOUBLE_LOCKED
, &sh
->dev
[i
].flags
);
1037 if (conf
->mddev
->gendisk
)
1038 trace_block_bio_remap(bdev_get_queue(bi
->bi_bdev
),
1039 bi
, disk_devt(conf
->mddev
->gendisk
),
1041 generic_make_request(bi
);
1044 if (s
->syncing
|| s
->expanding
|| s
->expanded
1046 md_sync_acct(rrdev
->bdev
, STRIPE_SECTORS
);
1048 set_bit(STRIPE_IO_STARTED
, &sh
->state
);
1051 rbi
->bi_bdev
= rrdev
->bdev
;
1053 BUG_ON(!(rw
& WRITE
));
1054 rbi
->bi_end_io
= raid5_end_write_request
;
1055 rbi
->bi_private
= sh
;
1057 pr_debug("%s: for %llu schedule op %ld on "
1058 "replacement disc %d\n",
1059 __func__
, (unsigned long long)sh
->sector
,
1061 atomic_inc(&sh
->count
);
1063 atomic_inc(&head_sh
->count
);
1064 if (use_new_offset(conf
, sh
))
1065 rbi
->bi_iter
.bi_sector
= (sh
->sector
1066 + rrdev
->new_data_offset
);
1068 rbi
->bi_iter
.bi_sector
= (sh
->sector
1069 + rrdev
->data_offset
);
1070 if (test_bit(R5_SkipCopy
, &sh
->dev
[i
].flags
))
1071 WARN_ON(test_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
));
1072 sh
->dev
[i
].rvec
.bv_page
= sh
->dev
[i
].page
;
1074 rbi
->bi_io_vec
[0].bv_len
= STRIPE_SIZE
;
1075 rbi
->bi_io_vec
[0].bv_offset
= 0;
1076 rbi
->bi_iter
.bi_size
= STRIPE_SIZE
;
1078 * If this is discard request, set bi_vcnt 0. We don't
1079 * want to confuse SCSI because SCSI will replace payload
1081 if (rw
& REQ_DISCARD
)
1083 if (conf
->mddev
->gendisk
)
1084 trace_block_bio_remap(bdev_get_queue(rbi
->bi_bdev
),
1085 rbi
, disk_devt(conf
->mddev
->gendisk
),
1087 generic_make_request(rbi
);
1089 if (!rdev
&& !rrdev
) {
1091 set_bit(STRIPE_DEGRADED
, &sh
->state
);
1092 pr_debug("skip op %ld on disc %d for sector %llu\n",
1093 bi
->bi_rw
, i
, (unsigned long long)sh
->sector
);
1094 clear_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
1095 set_bit(STRIPE_HANDLE
, &sh
->state
);
1098 if (!head_sh
->batch_head
)
1100 sh
= list_first_entry(&sh
->batch_list
, struct stripe_head
,
1107 static struct dma_async_tx_descriptor
*
1108 async_copy_data(int frombio
, struct bio
*bio
, struct page
**page
,
1109 sector_t sector
, struct dma_async_tx_descriptor
*tx
,
1110 struct stripe_head
*sh
)
1113 struct bvec_iter iter
;
1114 struct page
*bio_page
;
1116 struct async_submit_ctl submit
;
1117 enum async_tx_flags flags
= 0;
1119 if (bio
->bi_iter
.bi_sector
>= sector
)
1120 page_offset
= (signed)(bio
->bi_iter
.bi_sector
- sector
) * 512;
1122 page_offset
= (signed)(sector
- bio
->bi_iter
.bi_sector
) * -512;
1125 flags
|= ASYNC_TX_FENCE
;
1126 init_async_submit(&submit
, flags
, tx
, NULL
, NULL
, NULL
);
1128 bio_for_each_segment(bvl
, bio
, iter
) {
1129 int len
= bvl
.bv_len
;
1133 if (page_offset
< 0) {
1134 b_offset
= -page_offset
;
1135 page_offset
+= b_offset
;
1139 if (len
> 0 && page_offset
+ len
> STRIPE_SIZE
)
1140 clen
= STRIPE_SIZE
- page_offset
;
1145 b_offset
+= bvl
.bv_offset
;
1146 bio_page
= bvl
.bv_page
;
1148 if (sh
->raid_conf
->skip_copy
&&
1149 b_offset
== 0 && page_offset
== 0 &&
1150 clen
== STRIPE_SIZE
)
1153 tx
= async_memcpy(*page
, bio_page
, page_offset
,
1154 b_offset
, clen
, &submit
);
1156 tx
= async_memcpy(bio_page
, *page
, b_offset
,
1157 page_offset
, clen
, &submit
);
1159 /* chain the operations */
1160 submit
.depend_tx
= tx
;
1162 if (clen
< len
) /* hit end of page */
1170 static void ops_complete_biofill(void *stripe_head_ref
)
1172 struct stripe_head
*sh
= stripe_head_ref
;
1173 struct bio_list return_bi
= BIO_EMPTY_LIST
;
1176 pr_debug("%s: stripe %llu\n", __func__
,
1177 (unsigned long long)sh
->sector
);
1179 /* clear completed biofills */
1180 for (i
= sh
->disks
; i
--; ) {
1181 struct r5dev
*dev
= &sh
->dev
[i
];
1183 /* acknowledge completion of a biofill operation */
1184 /* and check if we need to reply to a read request,
1185 * new R5_Wantfill requests are held off until
1186 * !STRIPE_BIOFILL_RUN
1188 if (test_and_clear_bit(R5_Wantfill
, &dev
->flags
)) {
1189 struct bio
*rbi
, *rbi2
;
1194 while (rbi
&& rbi
->bi_iter
.bi_sector
<
1195 dev
->sector
+ STRIPE_SECTORS
) {
1196 rbi2
= r5_next_bio(rbi
, dev
->sector
);
1197 if (!raid5_dec_bi_active_stripes(rbi
))
1198 bio_list_add(&return_bi
, rbi
);
1203 clear_bit(STRIPE_BIOFILL_RUN
, &sh
->state
);
1205 return_io(&return_bi
);
1207 set_bit(STRIPE_HANDLE
, &sh
->state
);
1208 raid5_release_stripe(sh
);
1211 static void ops_run_biofill(struct stripe_head
*sh
)
1213 struct dma_async_tx_descriptor
*tx
= NULL
;
1214 struct async_submit_ctl submit
;
1217 BUG_ON(sh
->batch_head
);
1218 pr_debug("%s: stripe %llu\n", __func__
,
1219 (unsigned long long)sh
->sector
);
1221 for (i
= sh
->disks
; i
--; ) {
1222 struct r5dev
*dev
= &sh
->dev
[i
];
1223 if (test_bit(R5_Wantfill
, &dev
->flags
)) {
1225 spin_lock_irq(&sh
->stripe_lock
);
1226 dev
->read
= rbi
= dev
->toread
;
1228 spin_unlock_irq(&sh
->stripe_lock
);
1229 while (rbi
&& rbi
->bi_iter
.bi_sector
<
1230 dev
->sector
+ STRIPE_SECTORS
) {
1231 tx
= async_copy_data(0, rbi
, &dev
->page
,
1232 dev
->sector
, tx
, sh
);
1233 rbi
= r5_next_bio(rbi
, dev
->sector
);
1238 atomic_inc(&sh
->count
);
1239 init_async_submit(&submit
, ASYNC_TX_ACK
, tx
, ops_complete_biofill
, sh
, NULL
);
1240 async_trigger_callback(&submit
);
1243 static void mark_target_uptodate(struct stripe_head
*sh
, int target
)
1250 tgt
= &sh
->dev
[target
];
1251 set_bit(R5_UPTODATE
, &tgt
->flags
);
1252 BUG_ON(!test_bit(R5_Wantcompute
, &tgt
->flags
));
1253 clear_bit(R5_Wantcompute
, &tgt
->flags
);
1256 static void ops_complete_compute(void *stripe_head_ref
)
1258 struct stripe_head
*sh
= stripe_head_ref
;
1260 pr_debug("%s: stripe %llu\n", __func__
,
1261 (unsigned long long)sh
->sector
);
1263 /* mark the computed target(s) as uptodate */
1264 mark_target_uptodate(sh
, sh
->ops
.target
);
1265 mark_target_uptodate(sh
, sh
->ops
.target2
);
1267 clear_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
1268 if (sh
->check_state
== check_state_compute_run
)
1269 sh
->check_state
= check_state_compute_result
;
1270 set_bit(STRIPE_HANDLE
, &sh
->state
);
1271 raid5_release_stripe(sh
);
1274 /* return a pointer to the address conversion region of the scribble buffer */
1275 static addr_conv_t
*to_addr_conv(struct stripe_head
*sh
,
1276 struct raid5_percpu
*percpu
, int i
)
1280 addr
= flex_array_get(percpu
->scribble
, i
);
1281 return addr
+ sizeof(struct page
*) * (sh
->disks
+ 2);
1284 /* return a pointer to the address conversion region of the scribble buffer */
1285 static struct page
**to_addr_page(struct raid5_percpu
*percpu
, int i
)
1289 addr
= flex_array_get(percpu
->scribble
, i
);
1293 static struct dma_async_tx_descriptor
*
1294 ops_run_compute5(struct stripe_head
*sh
, struct raid5_percpu
*percpu
)
1296 int disks
= sh
->disks
;
1297 struct page
**xor_srcs
= to_addr_page(percpu
, 0);
1298 int target
= sh
->ops
.target
;
1299 struct r5dev
*tgt
= &sh
->dev
[target
];
1300 struct page
*xor_dest
= tgt
->page
;
1302 struct dma_async_tx_descriptor
*tx
;
1303 struct async_submit_ctl submit
;
1306 BUG_ON(sh
->batch_head
);
1308 pr_debug("%s: stripe %llu block: %d\n",
1309 __func__
, (unsigned long long)sh
->sector
, target
);
1310 BUG_ON(!test_bit(R5_Wantcompute
, &tgt
->flags
));
1312 for (i
= disks
; i
--; )
1314 xor_srcs
[count
++] = sh
->dev
[i
].page
;
1316 atomic_inc(&sh
->count
);
1318 init_async_submit(&submit
, ASYNC_TX_FENCE
|ASYNC_TX_XOR_ZERO_DST
, NULL
,
1319 ops_complete_compute
, sh
, to_addr_conv(sh
, percpu
, 0));
1320 if (unlikely(count
== 1))
1321 tx
= async_memcpy(xor_dest
, xor_srcs
[0], 0, 0, STRIPE_SIZE
, &submit
);
1323 tx
= async_xor(xor_dest
, xor_srcs
, 0, count
, STRIPE_SIZE
, &submit
);
1328 /* set_syndrome_sources - populate source buffers for gen_syndrome
1329 * @srcs - (struct page *) array of size sh->disks
1330 * @sh - stripe_head to parse
1332 * Populates srcs in proper layout order for the stripe and returns the
1333 * 'count' of sources to be used in a call to async_gen_syndrome. The P
1334 * destination buffer is recorded in srcs[count] and the Q destination
1335 * is recorded in srcs[count+1]].
1337 static int set_syndrome_sources(struct page
**srcs
,
1338 struct stripe_head
*sh
,
1341 int disks
= sh
->disks
;
1342 int syndrome_disks
= sh
->ddf_layout
? disks
: (disks
- 2);
1343 int d0_idx
= raid6_d0(sh
);
1347 for (i
= 0; i
< disks
; i
++)
1353 int slot
= raid6_idx_to_slot(i
, sh
, &count
, syndrome_disks
);
1354 struct r5dev
*dev
= &sh
->dev
[i
];
1356 if (i
== sh
->qd_idx
|| i
== sh
->pd_idx
||
1357 (srctype
== SYNDROME_SRC_ALL
) ||
1358 (srctype
== SYNDROME_SRC_WANT_DRAIN
&&
1359 test_bit(R5_Wantdrain
, &dev
->flags
)) ||
1360 (srctype
== SYNDROME_SRC_WRITTEN
&&
1362 srcs
[slot
] = sh
->dev
[i
].page
;
1363 i
= raid6_next_disk(i
, disks
);
1364 } while (i
!= d0_idx
);
1366 return syndrome_disks
;
1369 static struct dma_async_tx_descriptor
*
1370 ops_run_compute6_1(struct stripe_head
*sh
, struct raid5_percpu
*percpu
)
1372 int disks
= sh
->disks
;
1373 struct page
**blocks
= to_addr_page(percpu
, 0);
1375 int qd_idx
= sh
->qd_idx
;
1376 struct dma_async_tx_descriptor
*tx
;
1377 struct async_submit_ctl submit
;
1383 BUG_ON(sh
->batch_head
);
1384 if (sh
->ops
.target
< 0)
1385 target
= sh
->ops
.target2
;
1386 else if (sh
->ops
.target2
< 0)
1387 target
= sh
->ops
.target
;
1389 /* we should only have one valid target */
1392 pr_debug("%s: stripe %llu block: %d\n",
1393 __func__
, (unsigned long long)sh
->sector
, target
);
1395 tgt
= &sh
->dev
[target
];
1396 BUG_ON(!test_bit(R5_Wantcompute
, &tgt
->flags
));
1399 atomic_inc(&sh
->count
);
1401 if (target
== qd_idx
) {
1402 count
= set_syndrome_sources(blocks
, sh
, SYNDROME_SRC_ALL
);
1403 blocks
[count
] = NULL
; /* regenerating p is not necessary */
1404 BUG_ON(blocks
[count
+1] != dest
); /* q should already be set */
1405 init_async_submit(&submit
, ASYNC_TX_FENCE
, NULL
,
1406 ops_complete_compute
, sh
,
1407 to_addr_conv(sh
, percpu
, 0));
1408 tx
= async_gen_syndrome(blocks
, 0, count
+2, STRIPE_SIZE
, &submit
);
1410 /* Compute any data- or p-drive using XOR */
1412 for (i
= disks
; i
-- ; ) {
1413 if (i
== target
|| i
== qd_idx
)
1415 blocks
[count
++] = sh
->dev
[i
].page
;
1418 init_async_submit(&submit
, ASYNC_TX_FENCE
|ASYNC_TX_XOR_ZERO_DST
,
1419 NULL
, ops_complete_compute
, sh
,
1420 to_addr_conv(sh
, percpu
, 0));
1421 tx
= async_xor(dest
, blocks
, 0, count
, STRIPE_SIZE
, &submit
);
1427 static struct dma_async_tx_descriptor
*
1428 ops_run_compute6_2(struct stripe_head
*sh
, struct raid5_percpu
*percpu
)
1430 int i
, count
, disks
= sh
->disks
;
1431 int syndrome_disks
= sh
->ddf_layout
? disks
: disks
-2;
1432 int d0_idx
= raid6_d0(sh
);
1433 int faila
= -1, failb
= -1;
1434 int target
= sh
->ops
.target
;
1435 int target2
= sh
->ops
.target2
;
1436 struct r5dev
*tgt
= &sh
->dev
[target
];
1437 struct r5dev
*tgt2
= &sh
->dev
[target2
];
1438 struct dma_async_tx_descriptor
*tx
;
1439 struct page
**blocks
= to_addr_page(percpu
, 0);
1440 struct async_submit_ctl submit
;
1442 BUG_ON(sh
->batch_head
);
1443 pr_debug("%s: stripe %llu block1: %d block2: %d\n",
1444 __func__
, (unsigned long long)sh
->sector
, target
, target2
);
1445 BUG_ON(target
< 0 || target2
< 0);
1446 BUG_ON(!test_bit(R5_Wantcompute
, &tgt
->flags
));
1447 BUG_ON(!test_bit(R5_Wantcompute
, &tgt2
->flags
));
1449 /* we need to open-code set_syndrome_sources to handle the
1450 * slot number conversion for 'faila' and 'failb'
1452 for (i
= 0; i
< disks
; i
++)
1457 int slot
= raid6_idx_to_slot(i
, sh
, &count
, syndrome_disks
);
1459 blocks
[slot
] = sh
->dev
[i
].page
;
1465 i
= raid6_next_disk(i
, disks
);
1466 } while (i
!= d0_idx
);
1468 BUG_ON(faila
== failb
);
1471 pr_debug("%s: stripe: %llu faila: %d failb: %d\n",
1472 __func__
, (unsigned long long)sh
->sector
, faila
, failb
);
1474 atomic_inc(&sh
->count
);
1476 if (failb
== syndrome_disks
+1) {
1477 /* Q disk is one of the missing disks */
1478 if (faila
== syndrome_disks
) {
1479 /* Missing P+Q, just recompute */
1480 init_async_submit(&submit
, ASYNC_TX_FENCE
, NULL
,
1481 ops_complete_compute
, sh
,
1482 to_addr_conv(sh
, percpu
, 0));
1483 return async_gen_syndrome(blocks
, 0, syndrome_disks
+2,
1484 STRIPE_SIZE
, &submit
);
1488 int qd_idx
= sh
->qd_idx
;
1490 /* Missing D+Q: recompute D from P, then recompute Q */
1491 if (target
== qd_idx
)
1492 data_target
= target2
;
1494 data_target
= target
;
1497 for (i
= disks
; i
-- ; ) {
1498 if (i
== data_target
|| i
== qd_idx
)
1500 blocks
[count
++] = sh
->dev
[i
].page
;
1502 dest
= sh
->dev
[data_target
].page
;
1503 init_async_submit(&submit
,
1504 ASYNC_TX_FENCE
|ASYNC_TX_XOR_ZERO_DST
,
1506 to_addr_conv(sh
, percpu
, 0));
1507 tx
= async_xor(dest
, blocks
, 0, count
, STRIPE_SIZE
,
1510 count
= set_syndrome_sources(blocks
, sh
, SYNDROME_SRC_ALL
);
1511 init_async_submit(&submit
, ASYNC_TX_FENCE
, tx
,
1512 ops_complete_compute
, sh
,
1513 to_addr_conv(sh
, percpu
, 0));
1514 return async_gen_syndrome(blocks
, 0, count
+2,
1515 STRIPE_SIZE
, &submit
);
1518 init_async_submit(&submit
, ASYNC_TX_FENCE
, NULL
,
1519 ops_complete_compute
, sh
,
1520 to_addr_conv(sh
, percpu
, 0));
1521 if (failb
== syndrome_disks
) {
1522 /* We're missing D+P. */
1523 return async_raid6_datap_recov(syndrome_disks
+2,
1527 /* We're missing D+D. */
1528 return async_raid6_2data_recov(syndrome_disks
+2,
1529 STRIPE_SIZE
, faila
, failb
,
1535 static void ops_complete_prexor(void *stripe_head_ref
)
1537 struct stripe_head
*sh
= stripe_head_ref
;
1539 pr_debug("%s: stripe %llu\n", __func__
,
1540 (unsigned long long)sh
->sector
);
1543 static struct dma_async_tx_descriptor
*
1544 ops_run_prexor5(struct stripe_head
*sh
, struct raid5_percpu
*percpu
,
1545 struct dma_async_tx_descriptor
*tx
)
1547 int disks
= sh
->disks
;
1548 struct page
**xor_srcs
= to_addr_page(percpu
, 0);
1549 int count
= 0, pd_idx
= sh
->pd_idx
, i
;
1550 struct async_submit_ctl submit
;
1552 /* existing parity data subtracted */
1553 struct page
*xor_dest
= xor_srcs
[count
++] = sh
->dev
[pd_idx
].page
;
1555 BUG_ON(sh
->batch_head
);
1556 pr_debug("%s: stripe %llu\n", __func__
,
1557 (unsigned long long)sh
->sector
);
1559 for (i
= disks
; i
--; ) {
1560 struct r5dev
*dev
= &sh
->dev
[i
];
1561 /* Only process blocks that are known to be uptodate */
1562 if (test_bit(R5_Wantdrain
, &dev
->flags
))
1563 xor_srcs
[count
++] = dev
->page
;
1566 init_async_submit(&submit
, ASYNC_TX_FENCE
|ASYNC_TX_XOR_DROP_DST
, tx
,
1567 ops_complete_prexor
, sh
, to_addr_conv(sh
, percpu
, 0));
1568 tx
= async_xor(xor_dest
, xor_srcs
, 0, count
, STRIPE_SIZE
, &submit
);
1573 static struct dma_async_tx_descriptor
*
1574 ops_run_prexor6(struct stripe_head
*sh
, struct raid5_percpu
*percpu
,
1575 struct dma_async_tx_descriptor
*tx
)
1577 struct page
**blocks
= to_addr_page(percpu
, 0);
1579 struct async_submit_ctl submit
;
1581 pr_debug("%s: stripe %llu\n", __func__
,
1582 (unsigned long long)sh
->sector
);
1584 count
= set_syndrome_sources(blocks
, sh
, SYNDROME_SRC_WANT_DRAIN
);
1586 init_async_submit(&submit
, ASYNC_TX_FENCE
|ASYNC_TX_PQ_XOR_DST
, tx
,
1587 ops_complete_prexor
, sh
, to_addr_conv(sh
, percpu
, 0));
1588 tx
= async_gen_syndrome(blocks
, 0, count
+2, STRIPE_SIZE
, &submit
);
1593 static struct dma_async_tx_descriptor
*
1594 ops_run_biodrain(struct stripe_head
*sh
, struct dma_async_tx_descriptor
*tx
)
1596 int disks
= sh
->disks
;
1598 struct stripe_head
*head_sh
= sh
;
1600 pr_debug("%s: stripe %llu\n", __func__
,
1601 (unsigned long long)sh
->sector
);
1603 for (i
= disks
; i
--; ) {
1608 if (test_and_clear_bit(R5_Wantdrain
, &head_sh
->dev
[i
].flags
)) {
1613 spin_lock_irq(&sh
->stripe_lock
);
1614 chosen
= dev
->towrite
;
1615 dev
->towrite
= NULL
;
1616 sh
->overwrite_disks
= 0;
1617 BUG_ON(dev
->written
);
1618 wbi
= dev
->written
= chosen
;
1619 spin_unlock_irq(&sh
->stripe_lock
);
1620 WARN_ON(dev
->page
!= dev
->orig_page
);
1622 while (wbi
&& wbi
->bi_iter
.bi_sector
<
1623 dev
->sector
+ STRIPE_SECTORS
) {
1624 if (wbi
->bi_rw
& REQ_FUA
)
1625 set_bit(R5_WantFUA
, &dev
->flags
);
1626 if (wbi
->bi_rw
& REQ_SYNC
)
1627 set_bit(R5_SyncIO
, &dev
->flags
);
1628 if (wbi
->bi_rw
& REQ_DISCARD
)
1629 set_bit(R5_Discard
, &dev
->flags
);
1631 tx
= async_copy_data(1, wbi
, &dev
->page
,
1632 dev
->sector
, tx
, sh
);
1633 if (dev
->page
!= dev
->orig_page
) {
1634 set_bit(R5_SkipCopy
, &dev
->flags
);
1635 clear_bit(R5_UPTODATE
, &dev
->flags
);
1636 clear_bit(R5_OVERWRITE
, &dev
->flags
);
1639 wbi
= r5_next_bio(wbi
, dev
->sector
);
1642 if (head_sh
->batch_head
) {
1643 sh
= list_first_entry(&sh
->batch_list
,
1656 static void ops_complete_reconstruct(void *stripe_head_ref
)
1658 struct stripe_head
*sh
= stripe_head_ref
;
1659 int disks
= sh
->disks
;
1660 int pd_idx
= sh
->pd_idx
;
1661 int qd_idx
= sh
->qd_idx
;
1663 bool fua
= false, sync
= false, discard
= false;
1665 pr_debug("%s: stripe %llu\n", __func__
,
1666 (unsigned long long)sh
->sector
);
1668 for (i
= disks
; i
--; ) {
1669 fua
|= test_bit(R5_WantFUA
, &sh
->dev
[i
].flags
);
1670 sync
|= test_bit(R5_SyncIO
, &sh
->dev
[i
].flags
);
1671 discard
|= test_bit(R5_Discard
, &sh
->dev
[i
].flags
);
1674 for (i
= disks
; i
--; ) {
1675 struct r5dev
*dev
= &sh
->dev
[i
];
1677 if (dev
->written
|| i
== pd_idx
|| i
== qd_idx
) {
1678 if (!discard
&& !test_bit(R5_SkipCopy
, &dev
->flags
))
1679 set_bit(R5_UPTODATE
, &dev
->flags
);
1681 set_bit(R5_WantFUA
, &dev
->flags
);
1683 set_bit(R5_SyncIO
, &dev
->flags
);
1687 if (sh
->reconstruct_state
== reconstruct_state_drain_run
)
1688 sh
->reconstruct_state
= reconstruct_state_drain_result
;
1689 else if (sh
->reconstruct_state
== reconstruct_state_prexor_drain_run
)
1690 sh
->reconstruct_state
= reconstruct_state_prexor_drain_result
;
1692 BUG_ON(sh
->reconstruct_state
!= reconstruct_state_run
);
1693 sh
->reconstruct_state
= reconstruct_state_result
;
1696 set_bit(STRIPE_HANDLE
, &sh
->state
);
1697 raid5_release_stripe(sh
);
1701 ops_run_reconstruct5(struct stripe_head
*sh
, struct raid5_percpu
*percpu
,
1702 struct dma_async_tx_descriptor
*tx
)
1704 int disks
= sh
->disks
;
1705 struct page
**xor_srcs
;
1706 struct async_submit_ctl submit
;
1707 int count
, pd_idx
= sh
->pd_idx
, i
;
1708 struct page
*xor_dest
;
1710 unsigned long flags
;
1712 struct stripe_head
*head_sh
= sh
;
1715 pr_debug("%s: stripe %llu\n", __func__
,
1716 (unsigned long long)sh
->sector
);
1718 for (i
= 0; i
< sh
->disks
; i
++) {
1721 if (!test_bit(R5_Discard
, &sh
->dev
[i
].flags
))
1724 if (i
>= sh
->disks
) {
1725 atomic_inc(&sh
->count
);
1726 set_bit(R5_Discard
, &sh
->dev
[pd_idx
].flags
);
1727 ops_complete_reconstruct(sh
);
1732 xor_srcs
= to_addr_page(percpu
, j
);
1733 /* check if prexor is active which means only process blocks
1734 * that are part of a read-modify-write (written)
1736 if (head_sh
->reconstruct_state
== reconstruct_state_prexor_drain_run
) {
1738 xor_dest
= xor_srcs
[count
++] = sh
->dev
[pd_idx
].page
;
1739 for (i
= disks
; i
--; ) {
1740 struct r5dev
*dev
= &sh
->dev
[i
];
1741 if (head_sh
->dev
[i
].written
)
1742 xor_srcs
[count
++] = dev
->page
;
1745 xor_dest
= sh
->dev
[pd_idx
].page
;
1746 for (i
= disks
; i
--; ) {
1747 struct r5dev
*dev
= &sh
->dev
[i
];
1749 xor_srcs
[count
++] = dev
->page
;
1753 /* 1/ if we prexor'd then the dest is reused as a source
1754 * 2/ if we did not prexor then we are redoing the parity
1755 * set ASYNC_TX_XOR_DROP_DST and ASYNC_TX_XOR_ZERO_DST
1756 * for the synchronous xor case
1758 last_stripe
= !head_sh
->batch_head
||
1759 list_first_entry(&sh
->batch_list
,
1760 struct stripe_head
, batch_list
) == head_sh
;
1762 flags
= ASYNC_TX_ACK
|
1763 (prexor
? ASYNC_TX_XOR_DROP_DST
: ASYNC_TX_XOR_ZERO_DST
);
1765 atomic_inc(&head_sh
->count
);
1766 init_async_submit(&submit
, flags
, tx
, ops_complete_reconstruct
, head_sh
,
1767 to_addr_conv(sh
, percpu
, j
));
1769 flags
= prexor
? ASYNC_TX_XOR_DROP_DST
: ASYNC_TX_XOR_ZERO_DST
;
1770 init_async_submit(&submit
, flags
, tx
, NULL
, NULL
,
1771 to_addr_conv(sh
, percpu
, j
));
1774 if (unlikely(count
== 1))
1775 tx
= async_memcpy(xor_dest
, xor_srcs
[0], 0, 0, STRIPE_SIZE
, &submit
);
1777 tx
= async_xor(xor_dest
, xor_srcs
, 0, count
, STRIPE_SIZE
, &submit
);
1780 sh
= list_first_entry(&sh
->batch_list
, struct stripe_head
,
1787 ops_run_reconstruct6(struct stripe_head
*sh
, struct raid5_percpu
*percpu
,
1788 struct dma_async_tx_descriptor
*tx
)
1790 struct async_submit_ctl submit
;
1791 struct page
**blocks
;
1792 int count
, i
, j
= 0;
1793 struct stripe_head
*head_sh
= sh
;
1796 unsigned long txflags
;
1798 pr_debug("%s: stripe %llu\n", __func__
, (unsigned long long)sh
->sector
);
1800 for (i
= 0; i
< sh
->disks
; i
++) {
1801 if (sh
->pd_idx
== i
|| sh
->qd_idx
== i
)
1803 if (!test_bit(R5_Discard
, &sh
->dev
[i
].flags
))
1806 if (i
>= sh
->disks
) {
1807 atomic_inc(&sh
->count
);
1808 set_bit(R5_Discard
, &sh
->dev
[sh
->pd_idx
].flags
);
1809 set_bit(R5_Discard
, &sh
->dev
[sh
->qd_idx
].flags
);
1810 ops_complete_reconstruct(sh
);
1815 blocks
= to_addr_page(percpu
, j
);
1817 if (sh
->reconstruct_state
== reconstruct_state_prexor_drain_run
) {
1818 synflags
= SYNDROME_SRC_WRITTEN
;
1819 txflags
= ASYNC_TX_ACK
| ASYNC_TX_PQ_XOR_DST
;
1821 synflags
= SYNDROME_SRC_ALL
;
1822 txflags
= ASYNC_TX_ACK
;
1825 count
= set_syndrome_sources(blocks
, sh
, synflags
);
1826 last_stripe
= !head_sh
->batch_head
||
1827 list_first_entry(&sh
->batch_list
,
1828 struct stripe_head
, batch_list
) == head_sh
;
1831 atomic_inc(&head_sh
->count
);
1832 init_async_submit(&submit
, txflags
, tx
, ops_complete_reconstruct
,
1833 head_sh
, to_addr_conv(sh
, percpu
, j
));
1835 init_async_submit(&submit
, 0, tx
, NULL
, NULL
,
1836 to_addr_conv(sh
, percpu
, j
));
1837 tx
= async_gen_syndrome(blocks
, 0, count
+2, STRIPE_SIZE
, &submit
);
1840 sh
= list_first_entry(&sh
->batch_list
, struct stripe_head
,
1846 static void ops_complete_check(void *stripe_head_ref
)
1848 struct stripe_head
*sh
= stripe_head_ref
;
1850 pr_debug("%s: stripe %llu\n", __func__
,
1851 (unsigned long long)sh
->sector
);
1853 sh
->check_state
= check_state_check_result
;
1854 set_bit(STRIPE_HANDLE
, &sh
->state
);
1855 raid5_release_stripe(sh
);
1858 static void ops_run_check_p(struct stripe_head
*sh
, struct raid5_percpu
*percpu
)
1860 int disks
= sh
->disks
;
1861 int pd_idx
= sh
->pd_idx
;
1862 int qd_idx
= sh
->qd_idx
;
1863 struct page
*xor_dest
;
1864 struct page
**xor_srcs
= to_addr_page(percpu
, 0);
1865 struct dma_async_tx_descriptor
*tx
;
1866 struct async_submit_ctl submit
;
1870 pr_debug("%s: stripe %llu\n", __func__
,
1871 (unsigned long long)sh
->sector
);
1873 BUG_ON(sh
->batch_head
);
1875 xor_dest
= sh
->dev
[pd_idx
].page
;
1876 xor_srcs
[count
++] = xor_dest
;
1877 for (i
= disks
; i
--; ) {
1878 if (i
== pd_idx
|| i
== qd_idx
)
1880 xor_srcs
[count
++] = sh
->dev
[i
].page
;
1883 init_async_submit(&submit
, 0, NULL
, NULL
, NULL
,
1884 to_addr_conv(sh
, percpu
, 0));
1885 tx
= async_xor_val(xor_dest
, xor_srcs
, 0, count
, STRIPE_SIZE
,
1886 &sh
->ops
.zero_sum_result
, &submit
);
1888 atomic_inc(&sh
->count
);
1889 init_async_submit(&submit
, ASYNC_TX_ACK
, tx
, ops_complete_check
, sh
, NULL
);
1890 tx
= async_trigger_callback(&submit
);
1893 static void ops_run_check_pq(struct stripe_head
*sh
, struct raid5_percpu
*percpu
, int checkp
)
1895 struct page
**srcs
= to_addr_page(percpu
, 0);
1896 struct async_submit_ctl submit
;
1899 pr_debug("%s: stripe %llu checkp: %d\n", __func__
,
1900 (unsigned long long)sh
->sector
, checkp
);
1902 BUG_ON(sh
->batch_head
);
1903 count
= set_syndrome_sources(srcs
, sh
, SYNDROME_SRC_ALL
);
1907 atomic_inc(&sh
->count
);
1908 init_async_submit(&submit
, ASYNC_TX_ACK
, NULL
, ops_complete_check
,
1909 sh
, to_addr_conv(sh
, percpu
, 0));
1910 async_syndrome_val(srcs
, 0, count
+2, STRIPE_SIZE
,
1911 &sh
->ops
.zero_sum_result
, percpu
->spare_page
, &submit
);
1914 static void raid_run_ops(struct stripe_head
*sh
, unsigned long ops_request
)
1916 int overlap_clear
= 0, i
, disks
= sh
->disks
;
1917 struct dma_async_tx_descriptor
*tx
= NULL
;
1918 struct r5conf
*conf
= sh
->raid_conf
;
1919 int level
= conf
->level
;
1920 struct raid5_percpu
*percpu
;
1924 percpu
= per_cpu_ptr(conf
->percpu
, cpu
);
1925 if (test_bit(STRIPE_OP_BIOFILL
, &ops_request
)) {
1926 ops_run_biofill(sh
);
1930 if (test_bit(STRIPE_OP_COMPUTE_BLK
, &ops_request
)) {
1932 tx
= ops_run_compute5(sh
, percpu
);
1934 if (sh
->ops
.target2
< 0 || sh
->ops
.target
< 0)
1935 tx
= ops_run_compute6_1(sh
, percpu
);
1937 tx
= ops_run_compute6_2(sh
, percpu
);
1939 /* terminate the chain if reconstruct is not set to be run */
1940 if (tx
&& !test_bit(STRIPE_OP_RECONSTRUCT
, &ops_request
))
1944 if (test_bit(STRIPE_OP_PREXOR
, &ops_request
)) {
1946 tx
= ops_run_prexor5(sh
, percpu
, tx
);
1948 tx
= ops_run_prexor6(sh
, percpu
, tx
);
1951 if (test_bit(STRIPE_OP_BIODRAIN
, &ops_request
)) {
1952 tx
= ops_run_biodrain(sh
, tx
);
1956 if (test_bit(STRIPE_OP_RECONSTRUCT
, &ops_request
)) {
1958 ops_run_reconstruct5(sh
, percpu
, tx
);
1960 ops_run_reconstruct6(sh
, percpu
, tx
);
1963 if (test_bit(STRIPE_OP_CHECK
, &ops_request
)) {
1964 if (sh
->check_state
== check_state_run
)
1965 ops_run_check_p(sh
, percpu
);
1966 else if (sh
->check_state
== check_state_run_q
)
1967 ops_run_check_pq(sh
, percpu
, 0);
1968 else if (sh
->check_state
== check_state_run_pq
)
1969 ops_run_check_pq(sh
, percpu
, 1);
1974 if (overlap_clear
&& !sh
->batch_head
)
1975 for (i
= disks
; i
--; ) {
1976 struct r5dev
*dev
= &sh
->dev
[i
];
1977 if (test_and_clear_bit(R5_Overlap
, &dev
->flags
))
1978 wake_up(&sh
->raid_conf
->wait_for_overlap
);
1983 static struct stripe_head
*alloc_stripe(struct kmem_cache
*sc
, gfp_t gfp
)
1985 struct stripe_head
*sh
;
1987 sh
= kmem_cache_zalloc(sc
, gfp
);
1989 spin_lock_init(&sh
->stripe_lock
);
1990 spin_lock_init(&sh
->batch_lock
);
1991 INIT_LIST_HEAD(&sh
->batch_list
);
1992 INIT_LIST_HEAD(&sh
->lru
);
1993 atomic_set(&sh
->count
, 1);
1997 static int grow_one_stripe(struct r5conf
*conf
, gfp_t gfp
)
1999 struct stripe_head
*sh
;
2001 sh
= alloc_stripe(conf
->slab_cache
, gfp
);
2005 sh
->raid_conf
= conf
;
2007 if (grow_buffers(sh
, gfp
)) {
2009 kmem_cache_free(conf
->slab_cache
, sh
);
2012 sh
->hash_lock_index
=
2013 conf
->max_nr_stripes
% NR_STRIPE_HASH_LOCKS
;
2014 /* we just created an active stripe so... */
2015 atomic_inc(&conf
->active_stripes
);
2017 raid5_release_stripe(sh
);
2018 conf
->max_nr_stripes
++;
2022 static int grow_stripes(struct r5conf
*conf
, int num
)
2024 struct kmem_cache
*sc
;
2025 int devs
= max(conf
->raid_disks
, conf
->previous_raid_disks
);
2027 if (conf
->mddev
->gendisk
)
2028 sprintf(conf
->cache_name
[0],
2029 "raid%d-%s", conf
->level
, mdname(conf
->mddev
));
2031 sprintf(conf
->cache_name
[0],
2032 "raid%d-%p", conf
->level
, conf
->mddev
);
2033 sprintf(conf
->cache_name
[1], "%s-alt", conf
->cache_name
[0]);
2035 conf
->active_name
= 0;
2036 sc
= kmem_cache_create(conf
->cache_name
[conf
->active_name
],
2037 sizeof(struct stripe_head
)+(devs
-1)*sizeof(struct r5dev
),
2041 conf
->slab_cache
= sc
;
2042 conf
->pool_size
= devs
;
2044 if (!grow_one_stripe(conf
, GFP_KERNEL
))
2051 * scribble_len - return the required size of the scribble region
2052 * @num - total number of disks in the array
2054 * The size must be enough to contain:
2055 * 1/ a struct page pointer for each device in the array +2
2056 * 2/ room to convert each entry in (1) to its corresponding dma
2057 * (dma_map_page()) or page (page_address()) address.
2059 * Note: the +2 is for the destination buffers of the ddf/raid6 case where we
2060 * calculate over all devices (not just the data blocks), using zeros in place
2061 * of the P and Q blocks.
2063 static struct flex_array
*scribble_alloc(int num
, int cnt
, gfp_t flags
)
2065 struct flex_array
*ret
;
2068 len
= sizeof(struct page
*) * (num
+2) + sizeof(addr_conv_t
) * (num
+2);
2069 ret
= flex_array_alloc(len
, cnt
, flags
);
2072 /* always prealloc all elements, so no locking is required */
2073 if (flex_array_prealloc(ret
, 0, cnt
, flags
)) {
2074 flex_array_free(ret
);
2080 static int resize_chunks(struct r5conf
*conf
, int new_disks
, int new_sectors
)
2086 * Never shrink. And mddev_suspend() could deadlock if this is called
2087 * from raid5d. In that case, scribble_disks and scribble_sectors
2088 * should equal to new_disks and new_sectors
2090 if (conf
->scribble_disks
>= new_disks
&&
2091 conf
->scribble_sectors
>= new_sectors
)
2093 mddev_suspend(conf
->mddev
);
2095 for_each_present_cpu(cpu
) {
2096 struct raid5_percpu
*percpu
;
2097 struct flex_array
*scribble
;
2099 percpu
= per_cpu_ptr(conf
->percpu
, cpu
);
2100 scribble
= scribble_alloc(new_disks
,
2101 new_sectors
/ STRIPE_SECTORS
,
2105 flex_array_free(percpu
->scribble
);
2106 percpu
->scribble
= scribble
;
2113 mddev_resume(conf
->mddev
);
2115 conf
->scribble_disks
= new_disks
;
2116 conf
->scribble_sectors
= new_sectors
;
2121 static int resize_stripes(struct r5conf
*conf
, int newsize
)
2123 /* Make all the stripes able to hold 'newsize' devices.
2124 * New slots in each stripe get 'page' set to a new page.
2126 * This happens in stages:
2127 * 1/ create a new kmem_cache and allocate the required number of
2129 * 2/ gather all the old stripe_heads and transfer the pages across
2130 * to the new stripe_heads. This will have the side effect of
2131 * freezing the array as once all stripe_heads have been collected,
2132 * no IO will be possible. Old stripe heads are freed once their
2133 * pages have been transferred over, and the old kmem_cache is
2134 * freed when all stripes are done.
2135 * 3/ reallocate conf->disks to be suitable bigger. If this fails,
2136 * we simple return a failre status - no need to clean anything up.
2137 * 4/ allocate new pages for the new slots in the new stripe_heads.
2138 * If this fails, we don't bother trying the shrink the
2139 * stripe_heads down again, we just leave them as they are.
2140 * As each stripe_head is processed the new one is released into
2143 * Once step2 is started, we cannot afford to wait for a write,
2144 * so we use GFP_NOIO allocations.
2146 struct stripe_head
*osh
, *nsh
;
2147 LIST_HEAD(newstripes
);
2148 struct disk_info
*ndisks
;
2150 struct kmem_cache
*sc
;
2154 if (newsize
<= conf
->pool_size
)
2155 return 0; /* never bother to shrink */
2157 err
= md_allow_write(conf
->mddev
);
2162 sc
= kmem_cache_create(conf
->cache_name
[1-conf
->active_name
],
2163 sizeof(struct stripe_head
)+(newsize
-1)*sizeof(struct r5dev
),
2168 /* Need to ensure auto-resizing doesn't interfere */
2169 mutex_lock(&conf
->cache_size_mutex
);
2171 for (i
= conf
->max_nr_stripes
; i
; i
--) {
2172 nsh
= alloc_stripe(sc
, GFP_KERNEL
);
2176 nsh
->raid_conf
= conf
;
2177 list_add(&nsh
->lru
, &newstripes
);
2180 /* didn't get enough, give up */
2181 while (!list_empty(&newstripes
)) {
2182 nsh
= list_entry(newstripes
.next
, struct stripe_head
, lru
);
2183 list_del(&nsh
->lru
);
2184 kmem_cache_free(sc
, nsh
);
2186 kmem_cache_destroy(sc
);
2187 mutex_unlock(&conf
->cache_size_mutex
);
2190 /* Step 2 - Must use GFP_NOIO now.
2191 * OK, we have enough stripes, start collecting inactive
2192 * stripes and copying them over
2196 list_for_each_entry(nsh
, &newstripes
, lru
) {
2197 lock_device_hash_lock(conf
, hash
);
2198 wait_event_cmd(conf
->wait_for_stripe
,
2199 !list_empty(conf
->inactive_list
+ hash
),
2200 unlock_device_hash_lock(conf
, hash
),
2201 lock_device_hash_lock(conf
, hash
));
2202 osh
= get_free_stripe(conf
, hash
);
2203 unlock_device_hash_lock(conf
, hash
);
2205 for(i
=0; i
<conf
->pool_size
; i
++) {
2206 nsh
->dev
[i
].page
= osh
->dev
[i
].page
;
2207 nsh
->dev
[i
].orig_page
= osh
->dev
[i
].page
;
2209 nsh
->hash_lock_index
= hash
;
2210 kmem_cache_free(conf
->slab_cache
, osh
);
2212 if (cnt
>= conf
->max_nr_stripes
/ NR_STRIPE_HASH_LOCKS
+
2213 !!((conf
->max_nr_stripes
% NR_STRIPE_HASH_LOCKS
) > hash
)) {
2218 kmem_cache_destroy(conf
->slab_cache
);
2221 * At this point, we are holding all the stripes so the array
2222 * is completely stalled, so now is a good time to resize
2223 * conf->disks and the scribble region
2225 ndisks
= kzalloc(newsize
* sizeof(struct disk_info
), GFP_NOIO
);
2227 for (i
=0; i
<conf
->raid_disks
; i
++)
2228 ndisks
[i
] = conf
->disks
[i
];
2230 conf
->disks
= ndisks
;
2234 mutex_unlock(&conf
->cache_size_mutex
);
2235 /* Step 4, return new stripes to service */
2236 while(!list_empty(&newstripes
)) {
2237 nsh
= list_entry(newstripes
.next
, struct stripe_head
, lru
);
2238 list_del_init(&nsh
->lru
);
2240 for (i
=conf
->raid_disks
; i
< newsize
; i
++)
2241 if (nsh
->dev
[i
].page
== NULL
) {
2242 struct page
*p
= alloc_page(GFP_NOIO
);
2243 nsh
->dev
[i
].page
= p
;
2244 nsh
->dev
[i
].orig_page
= p
;
2248 raid5_release_stripe(nsh
);
2250 /* critical section pass, GFP_NOIO no longer needed */
2252 conf
->slab_cache
= sc
;
2253 conf
->active_name
= 1-conf
->active_name
;
2255 conf
->pool_size
= newsize
;
2259 static int drop_one_stripe(struct r5conf
*conf
)
2261 struct stripe_head
*sh
;
2262 int hash
= (conf
->max_nr_stripes
- 1) & STRIPE_HASH_LOCKS_MASK
;
2264 spin_lock_irq(conf
->hash_locks
+ hash
);
2265 sh
= get_free_stripe(conf
, hash
);
2266 spin_unlock_irq(conf
->hash_locks
+ hash
);
2269 BUG_ON(atomic_read(&sh
->count
));
2271 kmem_cache_free(conf
->slab_cache
, sh
);
2272 atomic_dec(&conf
->active_stripes
);
2273 conf
->max_nr_stripes
--;
2277 static void shrink_stripes(struct r5conf
*conf
)
2279 while (conf
->max_nr_stripes
&&
2280 drop_one_stripe(conf
))
2283 kmem_cache_destroy(conf
->slab_cache
);
2284 conf
->slab_cache
= NULL
;
2287 static void raid5_end_read_request(struct bio
* bi
)
2289 struct stripe_head
*sh
= bi
->bi_private
;
2290 struct r5conf
*conf
= sh
->raid_conf
;
2291 int disks
= sh
->disks
, i
;
2292 char b
[BDEVNAME_SIZE
];
2293 struct md_rdev
*rdev
= NULL
;
2296 for (i
=0 ; i
<disks
; i
++)
2297 if (bi
== &sh
->dev
[i
].req
)
2300 pr_debug("end_read_request %llu/%d, count: %d, error %d.\n",
2301 (unsigned long long)sh
->sector
, i
, atomic_read(&sh
->count
),
2307 if (test_bit(R5_ReadRepl
, &sh
->dev
[i
].flags
))
2308 /* If replacement finished while this request was outstanding,
2309 * 'replacement' might be NULL already.
2310 * In that case it moved down to 'rdev'.
2311 * rdev is not removed until all requests are finished.
2313 rdev
= conf
->disks
[i
].replacement
;
2315 rdev
= conf
->disks
[i
].rdev
;
2317 if (use_new_offset(conf
, sh
))
2318 s
= sh
->sector
+ rdev
->new_data_offset
;
2320 s
= sh
->sector
+ rdev
->data_offset
;
2321 if (!bi
->bi_error
) {
2322 set_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
);
2323 if (test_bit(R5_ReadError
, &sh
->dev
[i
].flags
)) {
2324 /* Note that this cannot happen on a
2325 * replacement device. We just fail those on
2330 "md/raid:%s: read error corrected"
2331 " (%lu sectors at %llu on %s)\n",
2332 mdname(conf
->mddev
), STRIPE_SECTORS
,
2333 (unsigned long long)s
,
2334 bdevname(rdev
->bdev
, b
));
2335 atomic_add(STRIPE_SECTORS
, &rdev
->corrected_errors
);
2336 clear_bit(R5_ReadError
, &sh
->dev
[i
].flags
);
2337 clear_bit(R5_ReWrite
, &sh
->dev
[i
].flags
);
2338 } else if (test_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
))
2339 clear_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
);
2341 if (atomic_read(&rdev
->read_errors
))
2342 atomic_set(&rdev
->read_errors
, 0);
2344 const char *bdn
= bdevname(rdev
->bdev
, b
);
2348 clear_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
);
2349 atomic_inc(&rdev
->read_errors
);
2350 if (test_bit(R5_ReadRepl
, &sh
->dev
[i
].flags
))
2353 "md/raid:%s: read error on replacement device "
2354 "(sector %llu on %s).\n",
2355 mdname(conf
->mddev
),
2356 (unsigned long long)s
,
2358 else if (conf
->mddev
->degraded
>= conf
->max_degraded
) {
2362 "md/raid:%s: read error not correctable "
2363 "(sector %llu on %s).\n",
2364 mdname(conf
->mddev
),
2365 (unsigned long long)s
,
2367 } else if (test_bit(R5_ReWrite
, &sh
->dev
[i
].flags
)) {
2372 "md/raid:%s: read error NOT corrected!! "
2373 "(sector %llu on %s).\n",
2374 mdname(conf
->mddev
),
2375 (unsigned long long)s
,
2377 } else if (atomic_read(&rdev
->read_errors
)
2378 > conf
->max_nr_stripes
)
2380 "md/raid:%s: Too many read errors, failing device %s.\n",
2381 mdname(conf
->mddev
), bdn
);
2384 if (set_bad
&& test_bit(In_sync
, &rdev
->flags
)
2385 && !test_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
))
2388 if (test_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
)) {
2389 set_bit(R5_ReadError
, &sh
->dev
[i
].flags
);
2390 clear_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
);
2392 set_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
);
2394 clear_bit(R5_ReadError
, &sh
->dev
[i
].flags
);
2395 clear_bit(R5_ReWrite
, &sh
->dev
[i
].flags
);
2397 && test_bit(In_sync
, &rdev
->flags
)
2398 && rdev_set_badblocks(
2399 rdev
, sh
->sector
, STRIPE_SECTORS
, 0)))
2400 md_error(conf
->mddev
, rdev
);
2403 rdev_dec_pending(rdev
, conf
->mddev
);
2404 clear_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
2405 set_bit(STRIPE_HANDLE
, &sh
->state
);
2406 raid5_release_stripe(sh
);
2409 static void raid5_end_write_request(struct bio
*bi
)
2411 struct stripe_head
*sh
= bi
->bi_private
;
2412 struct r5conf
*conf
= sh
->raid_conf
;
2413 int disks
= sh
->disks
, i
;
2414 struct md_rdev
*uninitialized_var(rdev
);
2417 int replacement
= 0;
2419 for (i
= 0 ; i
< disks
; i
++) {
2420 if (bi
== &sh
->dev
[i
].req
) {
2421 rdev
= conf
->disks
[i
].rdev
;
2424 if (bi
== &sh
->dev
[i
].rreq
) {
2425 rdev
= conf
->disks
[i
].replacement
;
2429 /* rdev was removed and 'replacement'
2430 * replaced it. rdev is not removed
2431 * until all requests are finished.
2433 rdev
= conf
->disks
[i
].rdev
;
2437 pr_debug("end_write_request %llu/%d, count %d, error: %d.\n",
2438 (unsigned long long)sh
->sector
, i
, atomic_read(&sh
->count
),
2447 md_error(conf
->mddev
, rdev
);
2448 else if (is_badblock(rdev
, sh
->sector
,
2450 &first_bad
, &bad_sectors
))
2451 set_bit(R5_MadeGoodRepl
, &sh
->dev
[i
].flags
);
2454 set_bit(STRIPE_DEGRADED
, &sh
->state
);
2455 set_bit(WriteErrorSeen
, &rdev
->flags
);
2456 set_bit(R5_WriteError
, &sh
->dev
[i
].flags
);
2457 if (!test_and_set_bit(WantReplacement
, &rdev
->flags
))
2458 set_bit(MD_RECOVERY_NEEDED
,
2459 &rdev
->mddev
->recovery
);
2460 } else if (is_badblock(rdev
, sh
->sector
,
2462 &first_bad
, &bad_sectors
)) {
2463 set_bit(R5_MadeGood
, &sh
->dev
[i
].flags
);
2464 if (test_bit(R5_ReadError
, &sh
->dev
[i
].flags
))
2465 /* That was a successful write so make
2466 * sure it looks like we already did
2469 set_bit(R5_ReWrite
, &sh
->dev
[i
].flags
);
2472 rdev_dec_pending(rdev
, conf
->mddev
);
2474 if (sh
->batch_head
&& bi
->bi_error
&& !replacement
)
2475 set_bit(STRIPE_BATCH_ERR
, &sh
->batch_head
->state
);
2477 if (!test_and_clear_bit(R5_DOUBLE_LOCKED
, &sh
->dev
[i
].flags
))
2478 clear_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
2479 set_bit(STRIPE_HANDLE
, &sh
->state
);
2480 raid5_release_stripe(sh
);
2482 if (sh
->batch_head
&& sh
!= sh
->batch_head
)
2483 raid5_release_stripe(sh
->batch_head
);
2486 static void raid5_build_block(struct stripe_head
*sh
, int i
, int previous
)
2488 struct r5dev
*dev
= &sh
->dev
[i
];
2490 bio_init(&dev
->req
);
2491 dev
->req
.bi_io_vec
= &dev
->vec
;
2492 dev
->req
.bi_max_vecs
= 1;
2493 dev
->req
.bi_private
= sh
;
2495 bio_init(&dev
->rreq
);
2496 dev
->rreq
.bi_io_vec
= &dev
->rvec
;
2497 dev
->rreq
.bi_max_vecs
= 1;
2498 dev
->rreq
.bi_private
= sh
;
2501 dev
->sector
= raid5_compute_blocknr(sh
, i
, previous
);
2504 static void error(struct mddev
*mddev
, struct md_rdev
*rdev
)
2506 char b
[BDEVNAME_SIZE
];
2507 struct r5conf
*conf
= mddev
->private;
2508 unsigned long flags
;
2509 pr_debug("raid456: error called\n");
2511 spin_lock_irqsave(&conf
->device_lock
, flags
);
2512 clear_bit(In_sync
, &rdev
->flags
);
2513 mddev
->degraded
= calc_degraded(conf
);
2514 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
2515 set_bit(MD_RECOVERY_INTR
, &mddev
->recovery
);
2517 set_bit(Blocked
, &rdev
->flags
);
2518 set_bit(Faulty
, &rdev
->flags
);
2519 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
2520 set_bit(MD_CHANGE_PENDING
, &mddev
->flags
);
2522 "md/raid:%s: Disk failure on %s, disabling device.\n"
2523 "md/raid:%s: Operation continuing on %d devices.\n",
2525 bdevname(rdev
->bdev
, b
),
2527 conf
->raid_disks
- mddev
->degraded
);
2531 * Input: a 'big' sector number,
2532 * Output: index of the data and parity disk, and the sector # in them.
2534 sector_t
raid5_compute_sector(struct r5conf
*conf
, sector_t r_sector
,
2535 int previous
, int *dd_idx
,
2536 struct stripe_head
*sh
)
2538 sector_t stripe
, stripe2
;
2539 sector_t chunk_number
;
2540 unsigned int chunk_offset
;
2543 sector_t new_sector
;
2544 int algorithm
= previous
? conf
->prev_algo
2546 int sectors_per_chunk
= previous
? conf
->prev_chunk_sectors
2547 : conf
->chunk_sectors
;
2548 int raid_disks
= previous
? conf
->previous_raid_disks
2550 int data_disks
= raid_disks
- conf
->max_degraded
;
2552 /* First compute the information on this sector */
2555 * Compute the chunk number and the sector offset inside the chunk
2557 chunk_offset
= sector_div(r_sector
, sectors_per_chunk
);
2558 chunk_number
= r_sector
;
2561 * Compute the stripe number
2563 stripe
= chunk_number
;
2564 *dd_idx
= sector_div(stripe
, data_disks
);
2567 * Select the parity disk based on the user selected algorithm.
2569 pd_idx
= qd_idx
= -1;
2570 switch(conf
->level
) {
2572 pd_idx
= data_disks
;
2575 switch (algorithm
) {
2576 case ALGORITHM_LEFT_ASYMMETRIC
:
2577 pd_idx
= data_disks
- sector_div(stripe2
, raid_disks
);
2578 if (*dd_idx
>= pd_idx
)
2581 case ALGORITHM_RIGHT_ASYMMETRIC
:
2582 pd_idx
= sector_div(stripe2
, raid_disks
);
2583 if (*dd_idx
>= pd_idx
)
2586 case ALGORITHM_LEFT_SYMMETRIC
:
2587 pd_idx
= data_disks
- sector_div(stripe2
, raid_disks
);
2588 *dd_idx
= (pd_idx
+ 1 + *dd_idx
) % raid_disks
;
2590 case ALGORITHM_RIGHT_SYMMETRIC
:
2591 pd_idx
= sector_div(stripe2
, raid_disks
);
2592 *dd_idx
= (pd_idx
+ 1 + *dd_idx
) % raid_disks
;
2594 case ALGORITHM_PARITY_0
:
2598 case ALGORITHM_PARITY_N
:
2599 pd_idx
= data_disks
;
2607 switch (algorithm
) {
2608 case ALGORITHM_LEFT_ASYMMETRIC
:
2609 pd_idx
= raid_disks
- 1 - sector_div(stripe2
, raid_disks
);
2610 qd_idx
= pd_idx
+ 1;
2611 if (pd_idx
== raid_disks
-1) {
2612 (*dd_idx
)++; /* Q D D D P */
2614 } else if (*dd_idx
>= pd_idx
)
2615 (*dd_idx
) += 2; /* D D P Q D */
2617 case ALGORITHM_RIGHT_ASYMMETRIC
:
2618 pd_idx
= sector_div(stripe2
, raid_disks
);
2619 qd_idx
= pd_idx
+ 1;
2620 if (pd_idx
== raid_disks
-1) {
2621 (*dd_idx
)++; /* Q D D D P */
2623 } else if (*dd_idx
>= pd_idx
)
2624 (*dd_idx
) += 2; /* D D P Q D */
2626 case ALGORITHM_LEFT_SYMMETRIC
:
2627 pd_idx
= raid_disks
- 1 - sector_div(stripe2
, raid_disks
);
2628 qd_idx
= (pd_idx
+ 1) % raid_disks
;
2629 *dd_idx
= (pd_idx
+ 2 + *dd_idx
) % raid_disks
;
2631 case ALGORITHM_RIGHT_SYMMETRIC
:
2632 pd_idx
= sector_div(stripe2
, raid_disks
);
2633 qd_idx
= (pd_idx
+ 1) % raid_disks
;
2634 *dd_idx
= (pd_idx
+ 2 + *dd_idx
) % raid_disks
;
2637 case ALGORITHM_PARITY_0
:
2642 case ALGORITHM_PARITY_N
:
2643 pd_idx
= data_disks
;
2644 qd_idx
= data_disks
+ 1;
2647 case ALGORITHM_ROTATING_ZERO_RESTART
:
2648 /* Exactly the same as RIGHT_ASYMMETRIC, but or
2649 * of blocks for computing Q is different.
2651 pd_idx
= sector_div(stripe2
, raid_disks
);
2652 qd_idx
= pd_idx
+ 1;
2653 if (pd_idx
== raid_disks
-1) {
2654 (*dd_idx
)++; /* Q D D D P */
2656 } else if (*dd_idx
>= pd_idx
)
2657 (*dd_idx
) += 2; /* D D P Q D */
2661 case ALGORITHM_ROTATING_N_RESTART
:
2662 /* Same a left_asymmetric, by first stripe is
2663 * D D D P Q rather than
2667 pd_idx
= raid_disks
- 1 - sector_div(stripe2
, raid_disks
);
2668 qd_idx
= pd_idx
+ 1;
2669 if (pd_idx
== raid_disks
-1) {
2670 (*dd_idx
)++; /* Q D D D P */
2672 } else if (*dd_idx
>= pd_idx
)
2673 (*dd_idx
) += 2; /* D D P Q D */
2677 case ALGORITHM_ROTATING_N_CONTINUE
:
2678 /* Same as left_symmetric but Q is before P */
2679 pd_idx
= raid_disks
- 1 - sector_div(stripe2
, raid_disks
);
2680 qd_idx
= (pd_idx
+ raid_disks
- 1) % raid_disks
;
2681 *dd_idx
= (pd_idx
+ 1 + *dd_idx
) % raid_disks
;
2685 case ALGORITHM_LEFT_ASYMMETRIC_6
:
2686 /* RAID5 left_asymmetric, with Q on last device */
2687 pd_idx
= data_disks
- sector_div(stripe2
, raid_disks
-1);
2688 if (*dd_idx
>= pd_idx
)
2690 qd_idx
= raid_disks
- 1;
2693 case ALGORITHM_RIGHT_ASYMMETRIC_6
:
2694 pd_idx
= sector_div(stripe2
, raid_disks
-1);
2695 if (*dd_idx
>= pd_idx
)
2697 qd_idx
= raid_disks
- 1;
2700 case ALGORITHM_LEFT_SYMMETRIC_6
:
2701 pd_idx
= data_disks
- sector_div(stripe2
, raid_disks
-1);
2702 *dd_idx
= (pd_idx
+ 1 + *dd_idx
) % (raid_disks
-1);
2703 qd_idx
= raid_disks
- 1;
2706 case ALGORITHM_RIGHT_SYMMETRIC_6
:
2707 pd_idx
= sector_div(stripe2
, raid_disks
-1);
2708 *dd_idx
= (pd_idx
+ 1 + *dd_idx
) % (raid_disks
-1);
2709 qd_idx
= raid_disks
- 1;
2712 case ALGORITHM_PARITY_0_6
:
2715 qd_idx
= raid_disks
- 1;
2725 sh
->pd_idx
= pd_idx
;
2726 sh
->qd_idx
= qd_idx
;
2727 sh
->ddf_layout
= ddf_layout
;
2730 * Finally, compute the new sector number
2732 new_sector
= (sector_t
)stripe
* sectors_per_chunk
+ chunk_offset
;
2736 sector_t
raid5_compute_blocknr(struct stripe_head
*sh
, int i
, int previous
)
2738 struct r5conf
*conf
= sh
->raid_conf
;
2739 int raid_disks
= sh
->disks
;
2740 int data_disks
= raid_disks
- conf
->max_degraded
;
2741 sector_t new_sector
= sh
->sector
, check
;
2742 int sectors_per_chunk
= previous
? conf
->prev_chunk_sectors
2743 : conf
->chunk_sectors
;
2744 int algorithm
= previous
? conf
->prev_algo
2748 sector_t chunk_number
;
2749 int dummy1
, dd_idx
= i
;
2751 struct stripe_head sh2
;
2753 chunk_offset
= sector_div(new_sector
, sectors_per_chunk
);
2754 stripe
= new_sector
;
2756 if (i
== sh
->pd_idx
)
2758 switch(conf
->level
) {
2761 switch (algorithm
) {
2762 case ALGORITHM_LEFT_ASYMMETRIC
:
2763 case ALGORITHM_RIGHT_ASYMMETRIC
:
2767 case ALGORITHM_LEFT_SYMMETRIC
:
2768 case ALGORITHM_RIGHT_SYMMETRIC
:
2771 i
-= (sh
->pd_idx
+ 1);
2773 case ALGORITHM_PARITY_0
:
2776 case ALGORITHM_PARITY_N
:
2783 if (i
== sh
->qd_idx
)
2784 return 0; /* It is the Q disk */
2785 switch (algorithm
) {
2786 case ALGORITHM_LEFT_ASYMMETRIC
:
2787 case ALGORITHM_RIGHT_ASYMMETRIC
:
2788 case ALGORITHM_ROTATING_ZERO_RESTART
:
2789 case ALGORITHM_ROTATING_N_RESTART
:
2790 if (sh
->pd_idx
== raid_disks
-1)
2791 i
--; /* Q D D D P */
2792 else if (i
> sh
->pd_idx
)
2793 i
-= 2; /* D D P Q D */
2795 case ALGORITHM_LEFT_SYMMETRIC
:
2796 case ALGORITHM_RIGHT_SYMMETRIC
:
2797 if (sh
->pd_idx
== raid_disks
-1)
2798 i
--; /* Q D D D P */
2803 i
-= (sh
->pd_idx
+ 2);
2806 case ALGORITHM_PARITY_0
:
2809 case ALGORITHM_PARITY_N
:
2811 case ALGORITHM_ROTATING_N_CONTINUE
:
2812 /* Like left_symmetric, but P is before Q */
2813 if (sh
->pd_idx
== 0)
2814 i
--; /* P D D D Q */
2819 i
-= (sh
->pd_idx
+ 1);
2822 case ALGORITHM_LEFT_ASYMMETRIC_6
:
2823 case ALGORITHM_RIGHT_ASYMMETRIC_6
:
2827 case ALGORITHM_LEFT_SYMMETRIC_6
:
2828 case ALGORITHM_RIGHT_SYMMETRIC_6
:
2830 i
+= data_disks
+ 1;
2831 i
-= (sh
->pd_idx
+ 1);
2833 case ALGORITHM_PARITY_0_6
:
2842 chunk_number
= stripe
* data_disks
+ i
;
2843 r_sector
= chunk_number
* sectors_per_chunk
+ chunk_offset
;
2845 check
= raid5_compute_sector(conf
, r_sector
,
2846 previous
, &dummy1
, &sh2
);
2847 if (check
!= sh
->sector
|| dummy1
!= dd_idx
|| sh2
.pd_idx
!= sh
->pd_idx
2848 || sh2
.qd_idx
!= sh
->qd_idx
) {
2849 printk(KERN_ERR
"md/raid:%s: compute_blocknr: map not correct\n",
2850 mdname(conf
->mddev
));
2857 schedule_reconstruction(struct stripe_head
*sh
, struct stripe_head_state
*s
,
2858 int rcw
, int expand
)
2860 int i
, pd_idx
= sh
->pd_idx
, qd_idx
= sh
->qd_idx
, disks
= sh
->disks
;
2861 struct r5conf
*conf
= sh
->raid_conf
;
2862 int level
= conf
->level
;
2866 for (i
= disks
; i
--; ) {
2867 struct r5dev
*dev
= &sh
->dev
[i
];
2870 set_bit(R5_LOCKED
, &dev
->flags
);
2871 set_bit(R5_Wantdrain
, &dev
->flags
);
2873 clear_bit(R5_UPTODATE
, &dev
->flags
);
2877 /* if we are not expanding this is a proper write request, and
2878 * there will be bios with new data to be drained into the
2883 /* False alarm, nothing to do */
2885 sh
->reconstruct_state
= reconstruct_state_drain_run
;
2886 set_bit(STRIPE_OP_BIODRAIN
, &s
->ops_request
);
2888 sh
->reconstruct_state
= reconstruct_state_run
;
2890 set_bit(STRIPE_OP_RECONSTRUCT
, &s
->ops_request
);
2892 if (s
->locked
+ conf
->max_degraded
== disks
)
2893 if (!test_and_set_bit(STRIPE_FULL_WRITE
, &sh
->state
))
2894 atomic_inc(&conf
->pending_full_writes
);
2896 BUG_ON(!(test_bit(R5_UPTODATE
, &sh
->dev
[pd_idx
].flags
) ||
2897 test_bit(R5_Wantcompute
, &sh
->dev
[pd_idx
].flags
)));
2898 BUG_ON(level
== 6 &&
2899 (!(test_bit(R5_UPTODATE
, &sh
->dev
[qd_idx
].flags
) ||
2900 test_bit(R5_Wantcompute
, &sh
->dev
[qd_idx
].flags
))));
2902 for (i
= disks
; i
--; ) {
2903 struct r5dev
*dev
= &sh
->dev
[i
];
2904 if (i
== pd_idx
|| i
== qd_idx
)
2908 (test_bit(R5_UPTODATE
, &dev
->flags
) ||
2909 test_bit(R5_Wantcompute
, &dev
->flags
))) {
2910 set_bit(R5_Wantdrain
, &dev
->flags
);
2911 set_bit(R5_LOCKED
, &dev
->flags
);
2912 clear_bit(R5_UPTODATE
, &dev
->flags
);
2917 /* False alarm - nothing to do */
2919 sh
->reconstruct_state
= reconstruct_state_prexor_drain_run
;
2920 set_bit(STRIPE_OP_PREXOR
, &s
->ops_request
);
2921 set_bit(STRIPE_OP_BIODRAIN
, &s
->ops_request
);
2922 set_bit(STRIPE_OP_RECONSTRUCT
, &s
->ops_request
);
2925 /* keep the parity disk(s) locked while asynchronous operations
2928 set_bit(R5_LOCKED
, &sh
->dev
[pd_idx
].flags
);
2929 clear_bit(R5_UPTODATE
, &sh
->dev
[pd_idx
].flags
);
2933 int qd_idx
= sh
->qd_idx
;
2934 struct r5dev
*dev
= &sh
->dev
[qd_idx
];
2936 set_bit(R5_LOCKED
, &dev
->flags
);
2937 clear_bit(R5_UPTODATE
, &dev
->flags
);
2941 pr_debug("%s: stripe %llu locked: %d ops_request: %lx\n",
2942 __func__
, (unsigned long long)sh
->sector
,
2943 s
->locked
, s
->ops_request
);
2947 * Each stripe/dev can have one or more bion attached.
2948 * toread/towrite point to the first in a chain.
2949 * The bi_next chain must be in order.
2951 static int add_stripe_bio(struct stripe_head
*sh
, struct bio
*bi
, int dd_idx
,
2952 int forwrite
, int previous
)
2955 struct r5conf
*conf
= sh
->raid_conf
;
2958 pr_debug("adding bi b#%llu to stripe s#%llu\n",
2959 (unsigned long long)bi
->bi_iter
.bi_sector
,
2960 (unsigned long long)sh
->sector
);
2963 * If several bio share a stripe. The bio bi_phys_segments acts as a
2964 * reference count to avoid race. The reference count should already be
2965 * increased before this function is called (for example, in
2966 * make_request()), so other bio sharing this stripe will not free the
2967 * stripe. If a stripe is owned by one stripe, the stripe lock will
2970 spin_lock_irq(&sh
->stripe_lock
);
2971 /* Don't allow new IO added to stripes in batch list */
2975 bip
= &sh
->dev
[dd_idx
].towrite
;
2979 bip
= &sh
->dev
[dd_idx
].toread
;
2980 while (*bip
&& (*bip
)->bi_iter
.bi_sector
< bi
->bi_iter
.bi_sector
) {
2981 if (bio_end_sector(*bip
) > bi
->bi_iter
.bi_sector
)
2983 bip
= & (*bip
)->bi_next
;
2985 if (*bip
&& (*bip
)->bi_iter
.bi_sector
< bio_end_sector(bi
))
2988 if (!forwrite
|| previous
)
2989 clear_bit(STRIPE_BATCH_READY
, &sh
->state
);
2991 BUG_ON(*bip
&& bi
->bi_next
&& (*bip
) != bi
->bi_next
);
2995 raid5_inc_bi_active_stripes(bi
);
2998 /* check if page is covered */
2999 sector_t sector
= sh
->dev
[dd_idx
].sector
;
3000 for (bi
=sh
->dev
[dd_idx
].towrite
;
3001 sector
< sh
->dev
[dd_idx
].sector
+ STRIPE_SECTORS
&&
3002 bi
&& bi
->bi_iter
.bi_sector
<= sector
;
3003 bi
= r5_next_bio(bi
, sh
->dev
[dd_idx
].sector
)) {
3004 if (bio_end_sector(bi
) >= sector
)
3005 sector
= bio_end_sector(bi
);
3007 if (sector
>= sh
->dev
[dd_idx
].sector
+ STRIPE_SECTORS
)
3008 if (!test_and_set_bit(R5_OVERWRITE
, &sh
->dev
[dd_idx
].flags
))
3009 sh
->overwrite_disks
++;
3012 pr_debug("added bi b#%llu to stripe s#%llu, disk %d.\n",
3013 (unsigned long long)(*bip
)->bi_iter
.bi_sector
,
3014 (unsigned long long)sh
->sector
, dd_idx
);
3016 if (conf
->mddev
->bitmap
&& firstwrite
) {
3017 /* Cannot hold spinlock over bitmap_startwrite,
3018 * but must ensure this isn't added to a batch until
3019 * we have added to the bitmap and set bm_seq.
3020 * So set STRIPE_BITMAP_PENDING to prevent
3022 * If multiple add_stripe_bio() calls race here they
3023 * much all set STRIPE_BITMAP_PENDING. So only the first one
3024 * to complete "bitmap_startwrite" gets to set
3025 * STRIPE_BIT_DELAY. This is important as once a stripe
3026 * is added to a batch, STRIPE_BIT_DELAY cannot be changed
3029 set_bit(STRIPE_BITMAP_PENDING
, &sh
->state
);
3030 spin_unlock_irq(&sh
->stripe_lock
);
3031 bitmap_startwrite(conf
->mddev
->bitmap
, sh
->sector
,
3033 spin_lock_irq(&sh
->stripe_lock
);
3034 clear_bit(STRIPE_BITMAP_PENDING
, &sh
->state
);
3035 if (!sh
->batch_head
) {
3036 sh
->bm_seq
= conf
->seq_flush
+1;
3037 set_bit(STRIPE_BIT_DELAY
, &sh
->state
);
3040 spin_unlock_irq(&sh
->stripe_lock
);
3042 if (stripe_can_batch(sh
))
3043 stripe_add_to_batch_list(conf
, sh
);
3047 set_bit(R5_Overlap
, &sh
->dev
[dd_idx
].flags
);
3048 spin_unlock_irq(&sh
->stripe_lock
);
3052 static void end_reshape(struct r5conf
*conf
);
3054 static void stripe_set_idx(sector_t stripe
, struct r5conf
*conf
, int previous
,
3055 struct stripe_head
*sh
)
3057 int sectors_per_chunk
=
3058 previous
? conf
->prev_chunk_sectors
: conf
->chunk_sectors
;
3060 int chunk_offset
= sector_div(stripe
, sectors_per_chunk
);
3061 int disks
= previous
? conf
->previous_raid_disks
: conf
->raid_disks
;
3063 raid5_compute_sector(conf
,
3064 stripe
* (disks
- conf
->max_degraded
)
3065 *sectors_per_chunk
+ chunk_offset
,
3071 handle_failed_stripe(struct r5conf
*conf
, struct stripe_head
*sh
,
3072 struct stripe_head_state
*s
, int disks
,
3073 struct bio_list
*return_bi
)
3076 BUG_ON(sh
->batch_head
);
3077 for (i
= disks
; i
--; ) {
3081 if (test_bit(R5_ReadError
, &sh
->dev
[i
].flags
)) {
3082 struct md_rdev
*rdev
;
3084 rdev
= rcu_dereference(conf
->disks
[i
].rdev
);
3085 if (rdev
&& test_bit(In_sync
, &rdev
->flags
))
3086 atomic_inc(&rdev
->nr_pending
);
3091 if (!rdev_set_badblocks(
3095 md_error(conf
->mddev
, rdev
);
3096 rdev_dec_pending(rdev
, conf
->mddev
);
3099 spin_lock_irq(&sh
->stripe_lock
);
3100 /* fail all writes first */
3101 bi
= sh
->dev
[i
].towrite
;
3102 sh
->dev
[i
].towrite
= NULL
;
3103 sh
->overwrite_disks
= 0;
3104 spin_unlock_irq(&sh
->stripe_lock
);
3108 r5l_stripe_write_finished(sh
);
3110 if (test_and_clear_bit(R5_Overlap
, &sh
->dev
[i
].flags
))
3111 wake_up(&conf
->wait_for_overlap
);
3113 while (bi
&& bi
->bi_iter
.bi_sector
<
3114 sh
->dev
[i
].sector
+ STRIPE_SECTORS
) {
3115 struct bio
*nextbi
= r5_next_bio(bi
, sh
->dev
[i
].sector
);
3117 bi
->bi_error
= -EIO
;
3118 if (!raid5_dec_bi_active_stripes(bi
)) {
3119 md_write_end(conf
->mddev
);
3120 bio_list_add(return_bi
, bi
);
3125 bitmap_endwrite(conf
->mddev
->bitmap
, sh
->sector
,
3126 STRIPE_SECTORS
, 0, 0);
3128 /* and fail all 'written' */
3129 bi
= sh
->dev
[i
].written
;
3130 sh
->dev
[i
].written
= NULL
;
3131 if (test_and_clear_bit(R5_SkipCopy
, &sh
->dev
[i
].flags
)) {
3132 WARN_ON(test_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
));
3133 sh
->dev
[i
].page
= sh
->dev
[i
].orig_page
;
3136 if (bi
) bitmap_end
= 1;
3137 while (bi
&& bi
->bi_iter
.bi_sector
<
3138 sh
->dev
[i
].sector
+ STRIPE_SECTORS
) {
3139 struct bio
*bi2
= r5_next_bio(bi
, sh
->dev
[i
].sector
);
3141 bi
->bi_error
= -EIO
;
3142 if (!raid5_dec_bi_active_stripes(bi
)) {
3143 md_write_end(conf
->mddev
);
3144 bio_list_add(return_bi
, bi
);
3149 /* fail any reads if this device is non-operational and
3150 * the data has not reached the cache yet.
3152 if (!test_bit(R5_Wantfill
, &sh
->dev
[i
].flags
) &&
3153 s
->failed
> conf
->max_degraded
&&
3154 (!test_bit(R5_Insync
, &sh
->dev
[i
].flags
) ||
3155 test_bit(R5_ReadError
, &sh
->dev
[i
].flags
))) {
3156 spin_lock_irq(&sh
->stripe_lock
);
3157 bi
= sh
->dev
[i
].toread
;
3158 sh
->dev
[i
].toread
= NULL
;
3159 spin_unlock_irq(&sh
->stripe_lock
);
3160 if (test_and_clear_bit(R5_Overlap
, &sh
->dev
[i
].flags
))
3161 wake_up(&conf
->wait_for_overlap
);
3164 while (bi
&& bi
->bi_iter
.bi_sector
<
3165 sh
->dev
[i
].sector
+ STRIPE_SECTORS
) {
3166 struct bio
*nextbi
=
3167 r5_next_bio(bi
, sh
->dev
[i
].sector
);
3169 bi
->bi_error
= -EIO
;
3170 if (!raid5_dec_bi_active_stripes(bi
))
3171 bio_list_add(return_bi
, bi
);
3176 bitmap_endwrite(conf
->mddev
->bitmap
, sh
->sector
,
3177 STRIPE_SECTORS
, 0, 0);
3178 /* If we were in the middle of a write the parity block might
3179 * still be locked - so just clear all R5_LOCKED flags
3181 clear_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
3186 if (test_and_clear_bit(STRIPE_FULL_WRITE
, &sh
->state
))
3187 if (atomic_dec_and_test(&conf
->pending_full_writes
))
3188 md_wakeup_thread(conf
->mddev
->thread
);
3192 handle_failed_sync(struct r5conf
*conf
, struct stripe_head
*sh
,
3193 struct stripe_head_state
*s
)
3198 BUG_ON(sh
->batch_head
);
3199 clear_bit(STRIPE_SYNCING
, &sh
->state
);
3200 if (test_and_clear_bit(R5_Overlap
, &sh
->dev
[sh
->pd_idx
].flags
))
3201 wake_up(&conf
->wait_for_overlap
);
3204 /* There is nothing more to do for sync/check/repair.
3205 * Don't even need to abort as that is handled elsewhere
3206 * if needed, and not always wanted e.g. if there is a known
3208 * For recover/replace we need to record a bad block on all
3209 * non-sync devices, or abort the recovery
3211 if (test_bit(MD_RECOVERY_RECOVER
, &conf
->mddev
->recovery
)) {
3212 /* During recovery devices cannot be removed, so
3213 * locking and refcounting of rdevs is not needed
3215 for (i
= 0; i
< conf
->raid_disks
; i
++) {
3216 struct md_rdev
*rdev
= conf
->disks
[i
].rdev
;
3218 && !test_bit(Faulty
, &rdev
->flags
)
3219 && !test_bit(In_sync
, &rdev
->flags
)
3220 && !rdev_set_badblocks(rdev
, sh
->sector
,
3223 rdev
= conf
->disks
[i
].replacement
;
3225 && !test_bit(Faulty
, &rdev
->flags
)
3226 && !test_bit(In_sync
, &rdev
->flags
)
3227 && !rdev_set_badblocks(rdev
, sh
->sector
,
3232 conf
->recovery_disabled
=
3233 conf
->mddev
->recovery_disabled
;
3235 md_done_sync(conf
->mddev
, STRIPE_SECTORS
, !abort
);
3238 static int want_replace(struct stripe_head
*sh
, int disk_idx
)
3240 struct md_rdev
*rdev
;
3242 /* Doing recovery so rcu locking not required */
3243 rdev
= sh
->raid_conf
->disks
[disk_idx
].replacement
;
3245 && !test_bit(Faulty
, &rdev
->flags
)
3246 && !test_bit(In_sync
, &rdev
->flags
)
3247 && (rdev
->recovery_offset
<= sh
->sector
3248 || rdev
->mddev
->recovery_cp
<= sh
->sector
))
3254 /* fetch_block - checks the given member device to see if its data needs
3255 * to be read or computed to satisfy a request.
3257 * Returns 1 when no more member devices need to be checked, otherwise returns
3258 * 0 to tell the loop in handle_stripe_fill to continue
3261 static int need_this_block(struct stripe_head
*sh
, struct stripe_head_state
*s
,
3262 int disk_idx
, int disks
)
3264 struct r5dev
*dev
= &sh
->dev
[disk_idx
];
3265 struct r5dev
*fdev
[2] = { &sh
->dev
[s
->failed_num
[0]],
3266 &sh
->dev
[s
->failed_num
[1]] };
3270 if (test_bit(R5_LOCKED
, &dev
->flags
) ||
3271 test_bit(R5_UPTODATE
, &dev
->flags
))
3272 /* No point reading this as we already have it or have
3273 * decided to get it.
3278 (dev
->towrite
&& !test_bit(R5_OVERWRITE
, &dev
->flags
)))
3279 /* We need this block to directly satisfy a request */
3282 if (s
->syncing
|| s
->expanding
||
3283 (s
->replacing
&& want_replace(sh
, disk_idx
)))
3284 /* When syncing, or expanding we read everything.
3285 * When replacing, we need the replaced block.
3289 if ((s
->failed
>= 1 && fdev
[0]->toread
) ||
3290 (s
->failed
>= 2 && fdev
[1]->toread
))
3291 /* If we want to read from a failed device, then
3292 * we need to actually read every other device.
3296 /* Sometimes neither read-modify-write nor reconstruct-write
3297 * cycles can work. In those cases we read every block we
3298 * can. Then the parity-update is certain to have enough to
3300 * This can only be a problem when we need to write something,
3301 * and some device has failed. If either of those tests
3302 * fail we need look no further.
3304 if (!s
->failed
|| !s
->to_write
)
3307 if (test_bit(R5_Insync
, &dev
->flags
) &&
3308 !test_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
3309 /* Pre-reads at not permitted until after short delay
3310 * to gather multiple requests. However if this
3311 * device is no Insync, the block could only be be computed
3312 * and there is no need to delay that.
3316 for (i
= 0; i
< s
->failed
&& i
< 2; i
++) {
3317 if (fdev
[i
]->towrite
&&
3318 !test_bit(R5_UPTODATE
, &fdev
[i
]->flags
) &&
3319 !test_bit(R5_OVERWRITE
, &fdev
[i
]->flags
))
3320 /* If we have a partial write to a failed
3321 * device, then we will need to reconstruct
3322 * the content of that device, so all other
3323 * devices must be read.
3328 /* If we are forced to do a reconstruct-write, either because
3329 * the current RAID6 implementation only supports that, or
3330 * or because parity cannot be trusted and we are currently
3331 * recovering it, there is extra need to be careful.
3332 * If one of the devices that we would need to read, because
3333 * it is not being overwritten (and maybe not written at all)
3334 * is missing/faulty, then we need to read everything we can.
3336 if (sh
->raid_conf
->level
!= 6 &&
3337 sh
->sector
< sh
->raid_conf
->mddev
->recovery_cp
)
3338 /* reconstruct-write isn't being forced */
3340 for (i
= 0; i
< s
->failed
&& i
< 2; i
++) {
3341 if (s
->failed_num
[i
] != sh
->pd_idx
&&
3342 s
->failed_num
[i
] != sh
->qd_idx
&&
3343 !test_bit(R5_UPTODATE
, &fdev
[i
]->flags
) &&
3344 !test_bit(R5_OVERWRITE
, &fdev
[i
]->flags
))
3351 static int fetch_block(struct stripe_head
*sh
, struct stripe_head_state
*s
,
3352 int disk_idx
, int disks
)
3354 struct r5dev
*dev
= &sh
->dev
[disk_idx
];
3356 /* is the data in this block needed, and can we get it? */
3357 if (need_this_block(sh
, s
, disk_idx
, disks
)) {
3358 /* we would like to get this block, possibly by computing it,
3359 * otherwise read it if the backing disk is insync
3361 BUG_ON(test_bit(R5_Wantcompute
, &dev
->flags
));
3362 BUG_ON(test_bit(R5_Wantread
, &dev
->flags
));
3363 BUG_ON(sh
->batch_head
);
3364 if ((s
->uptodate
== disks
- 1) &&
3365 (s
->failed
&& (disk_idx
== s
->failed_num
[0] ||
3366 disk_idx
== s
->failed_num
[1]))) {
3367 /* have disk failed, and we're requested to fetch it;
3370 pr_debug("Computing stripe %llu block %d\n",
3371 (unsigned long long)sh
->sector
, disk_idx
);
3372 set_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
3373 set_bit(STRIPE_OP_COMPUTE_BLK
, &s
->ops_request
);
3374 set_bit(R5_Wantcompute
, &dev
->flags
);
3375 sh
->ops
.target
= disk_idx
;
3376 sh
->ops
.target2
= -1; /* no 2nd target */
3378 /* Careful: from this point on 'uptodate' is in the eye
3379 * of raid_run_ops which services 'compute' operations
3380 * before writes. R5_Wantcompute flags a block that will
3381 * be R5_UPTODATE by the time it is needed for a
3382 * subsequent operation.
3386 } else if (s
->uptodate
== disks
-2 && s
->failed
>= 2) {
3387 /* Computing 2-failure is *very* expensive; only
3388 * do it if failed >= 2
3391 for (other
= disks
; other
--; ) {
3392 if (other
== disk_idx
)
3394 if (!test_bit(R5_UPTODATE
,
3395 &sh
->dev
[other
].flags
))
3399 pr_debug("Computing stripe %llu blocks %d,%d\n",
3400 (unsigned long long)sh
->sector
,
3402 set_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
3403 set_bit(STRIPE_OP_COMPUTE_BLK
, &s
->ops_request
);
3404 set_bit(R5_Wantcompute
, &sh
->dev
[disk_idx
].flags
);
3405 set_bit(R5_Wantcompute
, &sh
->dev
[other
].flags
);
3406 sh
->ops
.target
= disk_idx
;
3407 sh
->ops
.target2
= other
;
3411 } else if (test_bit(R5_Insync
, &dev
->flags
)) {
3412 set_bit(R5_LOCKED
, &dev
->flags
);
3413 set_bit(R5_Wantread
, &dev
->flags
);
3415 pr_debug("Reading block %d (sync=%d)\n",
3416 disk_idx
, s
->syncing
);
3424 * handle_stripe_fill - read or compute data to satisfy pending requests.
3426 static void handle_stripe_fill(struct stripe_head
*sh
,
3427 struct stripe_head_state
*s
,
3432 /* look for blocks to read/compute, skip this if a compute
3433 * is already in flight, or if the stripe contents are in the
3434 * midst of changing due to a write
3436 if (!test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
) && !sh
->check_state
&&
3437 !sh
->reconstruct_state
)
3438 for (i
= disks
; i
--; )
3439 if (fetch_block(sh
, s
, i
, disks
))
3441 set_bit(STRIPE_HANDLE
, &sh
->state
);
3444 static void break_stripe_batch_list(struct stripe_head
*head_sh
,
3445 unsigned long handle_flags
);
3446 /* handle_stripe_clean_event
3447 * any written block on an uptodate or failed drive can be returned.
3448 * Note that if we 'wrote' to a failed drive, it will be UPTODATE, but
3449 * never LOCKED, so we don't need to test 'failed' directly.
3451 static void handle_stripe_clean_event(struct r5conf
*conf
,
3452 struct stripe_head
*sh
, int disks
, struct bio_list
*return_bi
)
3456 int discard_pending
= 0;
3457 struct stripe_head
*head_sh
= sh
;
3458 bool do_endio
= false;
3460 for (i
= disks
; i
--; )
3461 if (sh
->dev
[i
].written
) {
3463 if (!test_bit(R5_LOCKED
, &dev
->flags
) &&
3464 (test_bit(R5_UPTODATE
, &dev
->flags
) ||
3465 test_bit(R5_Discard
, &dev
->flags
) ||
3466 test_bit(R5_SkipCopy
, &dev
->flags
))) {
3467 /* We can return any write requests */
3468 struct bio
*wbi
, *wbi2
;
3469 pr_debug("Return write for disc %d\n", i
);
3470 if (test_and_clear_bit(R5_Discard
, &dev
->flags
))
3471 clear_bit(R5_UPTODATE
, &dev
->flags
);
3472 if (test_and_clear_bit(R5_SkipCopy
, &dev
->flags
)) {
3473 WARN_ON(test_bit(R5_UPTODATE
, &dev
->flags
));
3478 dev
->page
= dev
->orig_page
;
3480 dev
->written
= NULL
;
3481 while (wbi
&& wbi
->bi_iter
.bi_sector
<
3482 dev
->sector
+ STRIPE_SECTORS
) {
3483 wbi2
= r5_next_bio(wbi
, dev
->sector
);
3484 if (!raid5_dec_bi_active_stripes(wbi
)) {
3485 md_write_end(conf
->mddev
);
3486 bio_list_add(return_bi
, wbi
);
3490 bitmap_endwrite(conf
->mddev
->bitmap
, sh
->sector
,
3492 !test_bit(STRIPE_DEGRADED
, &sh
->state
),
3494 if (head_sh
->batch_head
) {
3495 sh
= list_first_entry(&sh
->batch_list
,
3498 if (sh
!= head_sh
) {
3505 } else if (test_bit(R5_Discard
, &dev
->flags
))
3506 discard_pending
= 1;
3507 WARN_ON(test_bit(R5_SkipCopy
, &dev
->flags
));
3508 WARN_ON(dev
->page
!= dev
->orig_page
);
3511 r5l_stripe_write_finished(sh
);
3513 if (!discard_pending
&&
3514 test_bit(R5_Discard
, &sh
->dev
[sh
->pd_idx
].flags
)) {
3516 clear_bit(R5_Discard
, &sh
->dev
[sh
->pd_idx
].flags
);
3517 clear_bit(R5_UPTODATE
, &sh
->dev
[sh
->pd_idx
].flags
);
3518 if (sh
->qd_idx
>= 0) {
3519 clear_bit(R5_Discard
, &sh
->dev
[sh
->qd_idx
].flags
);
3520 clear_bit(R5_UPTODATE
, &sh
->dev
[sh
->qd_idx
].flags
);
3522 /* now that discard is done we can proceed with any sync */
3523 clear_bit(STRIPE_DISCARD
, &sh
->state
);
3525 * SCSI discard will change some bio fields and the stripe has
3526 * no updated data, so remove it from hash list and the stripe
3527 * will be reinitialized
3530 hash
= sh
->hash_lock_index
;
3531 spin_lock_irq(conf
->hash_locks
+ hash
);
3533 spin_unlock_irq(conf
->hash_locks
+ hash
);
3534 if (head_sh
->batch_head
) {
3535 sh
= list_first_entry(&sh
->batch_list
,
3536 struct stripe_head
, batch_list
);
3542 if (test_bit(STRIPE_SYNC_REQUESTED
, &sh
->state
))
3543 set_bit(STRIPE_HANDLE
, &sh
->state
);
3547 if (test_and_clear_bit(STRIPE_FULL_WRITE
, &sh
->state
))
3548 if (atomic_dec_and_test(&conf
->pending_full_writes
))
3549 md_wakeup_thread(conf
->mddev
->thread
);
3551 if (head_sh
->batch_head
&& do_endio
)
3552 break_stripe_batch_list(head_sh
, STRIPE_EXPAND_SYNC_FLAGS
);
3555 static void handle_stripe_dirtying(struct r5conf
*conf
,
3556 struct stripe_head
*sh
,
3557 struct stripe_head_state
*s
,
3560 int rmw
= 0, rcw
= 0, i
;
3561 sector_t recovery_cp
= conf
->mddev
->recovery_cp
;
3563 /* Check whether resync is now happening or should start.
3564 * If yes, then the array is dirty (after unclean shutdown or
3565 * initial creation), so parity in some stripes might be inconsistent.
3566 * In this case, we need to always do reconstruct-write, to ensure
3567 * that in case of drive failure or read-error correction, we
3568 * generate correct data from the parity.
3570 if (conf
->rmw_level
== PARITY_DISABLE_RMW
||
3571 (recovery_cp
< MaxSector
&& sh
->sector
>= recovery_cp
&&
3573 /* Calculate the real rcw later - for now make it
3574 * look like rcw is cheaper
3577 pr_debug("force RCW rmw_level=%u, recovery_cp=%llu sh->sector=%llu\n",
3578 conf
->rmw_level
, (unsigned long long)recovery_cp
,
3579 (unsigned long long)sh
->sector
);
3580 } else for (i
= disks
; i
--; ) {
3581 /* would I have to read this buffer for read_modify_write */
3582 struct r5dev
*dev
= &sh
->dev
[i
];
3583 if ((dev
->towrite
|| i
== sh
->pd_idx
|| i
== sh
->qd_idx
) &&
3584 !test_bit(R5_LOCKED
, &dev
->flags
) &&
3585 !(test_bit(R5_UPTODATE
, &dev
->flags
) ||
3586 test_bit(R5_Wantcompute
, &dev
->flags
))) {
3587 if (test_bit(R5_Insync
, &dev
->flags
))
3590 rmw
+= 2*disks
; /* cannot read it */
3592 /* Would I have to read this buffer for reconstruct_write */
3593 if (!test_bit(R5_OVERWRITE
, &dev
->flags
) &&
3594 i
!= sh
->pd_idx
&& i
!= sh
->qd_idx
&&
3595 !test_bit(R5_LOCKED
, &dev
->flags
) &&
3596 !(test_bit(R5_UPTODATE
, &dev
->flags
) ||
3597 test_bit(R5_Wantcompute
, &dev
->flags
))) {
3598 if (test_bit(R5_Insync
, &dev
->flags
))
3604 pr_debug("for sector %llu, rmw=%d rcw=%d\n",
3605 (unsigned long long)sh
->sector
, rmw
, rcw
);
3606 set_bit(STRIPE_HANDLE
, &sh
->state
);
3607 if ((rmw
< rcw
|| (rmw
== rcw
&& conf
->rmw_level
== PARITY_ENABLE_RMW
)) && rmw
> 0) {
3608 /* prefer read-modify-write, but need to get some data */
3609 if (conf
->mddev
->queue
)
3610 blk_add_trace_msg(conf
->mddev
->queue
,
3611 "raid5 rmw %llu %d",
3612 (unsigned long long)sh
->sector
, rmw
);
3613 for (i
= disks
; i
--; ) {
3614 struct r5dev
*dev
= &sh
->dev
[i
];
3615 if ((dev
->towrite
|| i
== sh
->pd_idx
|| i
== sh
->qd_idx
) &&
3616 !test_bit(R5_LOCKED
, &dev
->flags
) &&
3617 !(test_bit(R5_UPTODATE
, &dev
->flags
) ||
3618 test_bit(R5_Wantcompute
, &dev
->flags
)) &&
3619 test_bit(R5_Insync
, &dev
->flags
)) {
3620 if (test_bit(STRIPE_PREREAD_ACTIVE
,
3622 pr_debug("Read_old block %d for r-m-w\n",
3624 set_bit(R5_LOCKED
, &dev
->flags
);
3625 set_bit(R5_Wantread
, &dev
->flags
);
3628 set_bit(STRIPE_DELAYED
, &sh
->state
);
3629 set_bit(STRIPE_HANDLE
, &sh
->state
);
3634 if ((rcw
< rmw
|| (rcw
== rmw
&& conf
->rmw_level
!= PARITY_ENABLE_RMW
)) && rcw
> 0) {
3635 /* want reconstruct write, but need to get some data */
3638 for (i
= disks
; i
--; ) {
3639 struct r5dev
*dev
= &sh
->dev
[i
];
3640 if (!test_bit(R5_OVERWRITE
, &dev
->flags
) &&
3641 i
!= sh
->pd_idx
&& i
!= sh
->qd_idx
&&
3642 !test_bit(R5_LOCKED
, &dev
->flags
) &&
3643 !(test_bit(R5_UPTODATE
, &dev
->flags
) ||
3644 test_bit(R5_Wantcompute
, &dev
->flags
))) {
3646 if (test_bit(R5_Insync
, &dev
->flags
) &&
3647 test_bit(STRIPE_PREREAD_ACTIVE
,
3649 pr_debug("Read_old block "
3650 "%d for Reconstruct\n", i
);
3651 set_bit(R5_LOCKED
, &dev
->flags
);
3652 set_bit(R5_Wantread
, &dev
->flags
);
3656 set_bit(STRIPE_DELAYED
, &sh
->state
);
3657 set_bit(STRIPE_HANDLE
, &sh
->state
);
3661 if (rcw
&& conf
->mddev
->queue
)
3662 blk_add_trace_msg(conf
->mddev
->queue
, "raid5 rcw %llu %d %d %d",
3663 (unsigned long long)sh
->sector
,
3664 rcw
, qread
, test_bit(STRIPE_DELAYED
, &sh
->state
));
3667 if (rcw
> disks
&& rmw
> disks
&&
3668 !test_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
3669 set_bit(STRIPE_DELAYED
, &sh
->state
);
3671 /* now if nothing is locked, and if we have enough data,
3672 * we can start a write request
3674 /* since handle_stripe can be called at any time we need to handle the
3675 * case where a compute block operation has been submitted and then a
3676 * subsequent call wants to start a write request. raid_run_ops only
3677 * handles the case where compute block and reconstruct are requested
3678 * simultaneously. If this is not the case then new writes need to be
3679 * held off until the compute completes.
3681 if ((s
->req_compute
|| !test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
)) &&
3682 (s
->locked
== 0 && (rcw
== 0 || rmw
== 0) &&
3683 !test_bit(STRIPE_BIT_DELAY
, &sh
->state
)))
3684 schedule_reconstruction(sh
, s
, rcw
== 0, 0);
3687 static void handle_parity_checks5(struct r5conf
*conf
, struct stripe_head
*sh
,
3688 struct stripe_head_state
*s
, int disks
)
3690 struct r5dev
*dev
= NULL
;
3692 BUG_ON(sh
->batch_head
);
3693 set_bit(STRIPE_HANDLE
, &sh
->state
);
3695 switch (sh
->check_state
) {
3696 case check_state_idle
:
3697 /* start a new check operation if there are no failures */
3698 if (s
->failed
== 0) {
3699 BUG_ON(s
->uptodate
!= disks
);
3700 sh
->check_state
= check_state_run
;
3701 set_bit(STRIPE_OP_CHECK
, &s
->ops_request
);
3702 clear_bit(R5_UPTODATE
, &sh
->dev
[sh
->pd_idx
].flags
);
3706 dev
= &sh
->dev
[s
->failed_num
[0]];
3708 case check_state_compute_result
:
3709 sh
->check_state
= check_state_idle
;
3711 dev
= &sh
->dev
[sh
->pd_idx
];
3713 /* check that a write has not made the stripe insync */
3714 if (test_bit(STRIPE_INSYNC
, &sh
->state
))
3717 /* either failed parity check, or recovery is happening */
3718 BUG_ON(!test_bit(R5_UPTODATE
, &dev
->flags
));
3719 BUG_ON(s
->uptodate
!= disks
);
3721 set_bit(R5_LOCKED
, &dev
->flags
);
3723 set_bit(R5_Wantwrite
, &dev
->flags
);
3725 clear_bit(STRIPE_DEGRADED
, &sh
->state
);
3726 set_bit(STRIPE_INSYNC
, &sh
->state
);
3728 case check_state_run
:
3729 break; /* we will be called again upon completion */
3730 case check_state_check_result
:
3731 sh
->check_state
= check_state_idle
;
3733 /* if a failure occurred during the check operation, leave
3734 * STRIPE_INSYNC not set and let the stripe be handled again
3739 /* handle a successful check operation, if parity is correct
3740 * we are done. Otherwise update the mismatch count and repair
3741 * parity if !MD_RECOVERY_CHECK
3743 if ((sh
->ops
.zero_sum_result
& SUM_CHECK_P_RESULT
) == 0)
3744 /* parity is correct (on disc,
3745 * not in buffer any more)
3747 set_bit(STRIPE_INSYNC
, &sh
->state
);
3749 atomic64_add(STRIPE_SECTORS
, &conf
->mddev
->resync_mismatches
);
3750 if (test_bit(MD_RECOVERY_CHECK
, &conf
->mddev
->recovery
))
3751 /* don't try to repair!! */
3752 set_bit(STRIPE_INSYNC
, &sh
->state
);
3754 sh
->check_state
= check_state_compute_run
;
3755 set_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
3756 set_bit(STRIPE_OP_COMPUTE_BLK
, &s
->ops_request
);
3757 set_bit(R5_Wantcompute
,
3758 &sh
->dev
[sh
->pd_idx
].flags
);
3759 sh
->ops
.target
= sh
->pd_idx
;
3760 sh
->ops
.target2
= -1;
3765 case check_state_compute_run
:
3768 printk(KERN_ERR
"%s: unknown check_state: %d sector: %llu\n",
3769 __func__
, sh
->check_state
,
3770 (unsigned long long) sh
->sector
);
3775 static void handle_parity_checks6(struct r5conf
*conf
, struct stripe_head
*sh
,
3776 struct stripe_head_state
*s
,
3779 int pd_idx
= sh
->pd_idx
;
3780 int qd_idx
= sh
->qd_idx
;
3783 BUG_ON(sh
->batch_head
);
3784 set_bit(STRIPE_HANDLE
, &sh
->state
);
3786 BUG_ON(s
->failed
> 2);
3788 /* Want to check and possibly repair P and Q.
3789 * However there could be one 'failed' device, in which
3790 * case we can only check one of them, possibly using the
3791 * other to generate missing data
3794 switch (sh
->check_state
) {
3795 case check_state_idle
:
3796 /* start a new check operation if there are < 2 failures */
3797 if (s
->failed
== s
->q_failed
) {
3798 /* The only possible failed device holds Q, so it
3799 * makes sense to check P (If anything else were failed,
3800 * we would have used P to recreate it).
3802 sh
->check_state
= check_state_run
;
3804 if (!s
->q_failed
&& s
->failed
< 2) {
3805 /* Q is not failed, and we didn't use it to generate
3806 * anything, so it makes sense to check it
3808 if (sh
->check_state
== check_state_run
)
3809 sh
->check_state
= check_state_run_pq
;
3811 sh
->check_state
= check_state_run_q
;
3814 /* discard potentially stale zero_sum_result */
3815 sh
->ops
.zero_sum_result
= 0;
3817 if (sh
->check_state
== check_state_run
) {
3818 /* async_xor_zero_sum destroys the contents of P */
3819 clear_bit(R5_UPTODATE
, &sh
->dev
[pd_idx
].flags
);
3822 if (sh
->check_state
>= check_state_run
&&
3823 sh
->check_state
<= check_state_run_pq
) {
3824 /* async_syndrome_zero_sum preserves P and Q, so
3825 * no need to mark them !uptodate here
3827 set_bit(STRIPE_OP_CHECK
, &s
->ops_request
);
3831 /* we have 2-disk failure */
3832 BUG_ON(s
->failed
!= 2);
3834 case check_state_compute_result
:
3835 sh
->check_state
= check_state_idle
;
3837 /* check that a write has not made the stripe insync */
3838 if (test_bit(STRIPE_INSYNC
, &sh
->state
))
3841 /* now write out any block on a failed drive,
3842 * or P or Q if they were recomputed
3844 BUG_ON(s
->uptodate
< disks
- 1); /* We don't need Q to recover */
3845 if (s
->failed
== 2) {
3846 dev
= &sh
->dev
[s
->failed_num
[1]];
3848 set_bit(R5_LOCKED
, &dev
->flags
);
3849 set_bit(R5_Wantwrite
, &dev
->flags
);
3851 if (s
->failed
>= 1) {
3852 dev
= &sh
->dev
[s
->failed_num
[0]];
3854 set_bit(R5_LOCKED
, &dev
->flags
);
3855 set_bit(R5_Wantwrite
, &dev
->flags
);
3857 if (sh
->ops
.zero_sum_result
& SUM_CHECK_P_RESULT
) {
3858 dev
= &sh
->dev
[pd_idx
];
3860 set_bit(R5_LOCKED
, &dev
->flags
);
3861 set_bit(R5_Wantwrite
, &dev
->flags
);
3863 if (sh
->ops
.zero_sum_result
& SUM_CHECK_Q_RESULT
) {
3864 dev
= &sh
->dev
[qd_idx
];
3866 set_bit(R5_LOCKED
, &dev
->flags
);
3867 set_bit(R5_Wantwrite
, &dev
->flags
);
3869 clear_bit(STRIPE_DEGRADED
, &sh
->state
);
3871 set_bit(STRIPE_INSYNC
, &sh
->state
);
3873 case check_state_run
:
3874 case check_state_run_q
:
3875 case check_state_run_pq
:
3876 break; /* we will be called again upon completion */
3877 case check_state_check_result
:
3878 sh
->check_state
= check_state_idle
;
3880 /* handle a successful check operation, if parity is correct
3881 * we are done. Otherwise update the mismatch count and repair
3882 * parity if !MD_RECOVERY_CHECK
3884 if (sh
->ops
.zero_sum_result
== 0) {
3885 /* both parities are correct */
3887 set_bit(STRIPE_INSYNC
, &sh
->state
);
3889 /* in contrast to the raid5 case we can validate
3890 * parity, but still have a failure to write
3893 sh
->check_state
= check_state_compute_result
;
3894 /* Returning at this point means that we may go
3895 * off and bring p and/or q uptodate again so
3896 * we make sure to check zero_sum_result again
3897 * to verify if p or q need writeback
3901 atomic64_add(STRIPE_SECTORS
, &conf
->mddev
->resync_mismatches
);
3902 if (test_bit(MD_RECOVERY_CHECK
, &conf
->mddev
->recovery
))
3903 /* don't try to repair!! */
3904 set_bit(STRIPE_INSYNC
, &sh
->state
);
3906 int *target
= &sh
->ops
.target
;
3908 sh
->ops
.target
= -1;
3909 sh
->ops
.target2
= -1;
3910 sh
->check_state
= check_state_compute_run
;
3911 set_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
3912 set_bit(STRIPE_OP_COMPUTE_BLK
, &s
->ops_request
);
3913 if (sh
->ops
.zero_sum_result
& SUM_CHECK_P_RESULT
) {
3914 set_bit(R5_Wantcompute
,
3915 &sh
->dev
[pd_idx
].flags
);
3917 target
= &sh
->ops
.target2
;
3920 if (sh
->ops
.zero_sum_result
& SUM_CHECK_Q_RESULT
) {
3921 set_bit(R5_Wantcompute
,
3922 &sh
->dev
[qd_idx
].flags
);
3929 case check_state_compute_run
:
3932 printk(KERN_ERR
"%s: unknown check_state: %d sector: %llu\n",
3933 __func__
, sh
->check_state
,
3934 (unsigned long long) sh
->sector
);
3939 static void handle_stripe_expansion(struct r5conf
*conf
, struct stripe_head
*sh
)
3943 /* We have read all the blocks in this stripe and now we need to
3944 * copy some of them into a target stripe for expand.
3946 struct dma_async_tx_descriptor
*tx
= NULL
;
3947 BUG_ON(sh
->batch_head
);
3948 clear_bit(STRIPE_EXPAND_SOURCE
, &sh
->state
);
3949 for (i
= 0; i
< sh
->disks
; i
++)
3950 if (i
!= sh
->pd_idx
&& i
!= sh
->qd_idx
) {
3952 struct stripe_head
*sh2
;
3953 struct async_submit_ctl submit
;
3955 sector_t bn
= raid5_compute_blocknr(sh
, i
, 1);
3956 sector_t s
= raid5_compute_sector(conf
, bn
, 0,
3958 sh2
= raid5_get_active_stripe(conf
, s
, 0, 1, 1);
3960 /* so far only the early blocks of this stripe
3961 * have been requested. When later blocks
3962 * get requested, we will try again
3965 if (!test_bit(STRIPE_EXPANDING
, &sh2
->state
) ||
3966 test_bit(R5_Expanded
, &sh2
->dev
[dd_idx
].flags
)) {
3967 /* must have already done this block */
3968 raid5_release_stripe(sh2
);
3972 /* place all the copies on one channel */
3973 init_async_submit(&submit
, 0, tx
, NULL
, NULL
, NULL
);
3974 tx
= async_memcpy(sh2
->dev
[dd_idx
].page
,
3975 sh
->dev
[i
].page
, 0, 0, STRIPE_SIZE
,
3978 set_bit(R5_Expanded
, &sh2
->dev
[dd_idx
].flags
);
3979 set_bit(R5_UPTODATE
, &sh2
->dev
[dd_idx
].flags
);
3980 for (j
= 0; j
< conf
->raid_disks
; j
++)
3981 if (j
!= sh2
->pd_idx
&&
3983 !test_bit(R5_Expanded
, &sh2
->dev
[j
].flags
))
3985 if (j
== conf
->raid_disks
) {
3986 set_bit(STRIPE_EXPAND_READY
, &sh2
->state
);
3987 set_bit(STRIPE_HANDLE
, &sh2
->state
);
3989 raid5_release_stripe(sh2
);
3992 /* done submitting copies, wait for them to complete */
3993 async_tx_quiesce(&tx
);
3997 * handle_stripe - do things to a stripe.
3999 * We lock the stripe by setting STRIPE_ACTIVE and then examine the
4000 * state of various bits to see what needs to be done.
4002 * return some read requests which now have data
4003 * return some write requests which are safely on storage
4004 * schedule a read on some buffers
4005 * schedule a write of some buffers
4006 * return confirmation of parity correctness
4010 static void analyse_stripe(struct stripe_head
*sh
, struct stripe_head_state
*s
)
4012 struct r5conf
*conf
= sh
->raid_conf
;
4013 int disks
= sh
->disks
;
4016 int do_recovery
= 0;
4018 memset(s
, 0, sizeof(*s
));
4020 s
->expanding
= test_bit(STRIPE_EXPAND_SOURCE
, &sh
->state
) && !sh
->batch_head
;
4021 s
->expanded
= test_bit(STRIPE_EXPAND_READY
, &sh
->state
) && !sh
->batch_head
;
4022 s
->failed_num
[0] = -1;
4023 s
->failed_num
[1] = -1;
4024 s
->log_failed
= r5l_log_disk_error(conf
);
4026 /* Now to look around and see what can be done */
4028 for (i
=disks
; i
--; ) {
4029 struct md_rdev
*rdev
;
4036 pr_debug("check %d: state 0x%lx read %p write %p written %p\n",
4038 dev
->toread
, dev
->towrite
, dev
->written
);
4039 /* maybe we can reply to a read
4041 * new wantfill requests are only permitted while
4042 * ops_complete_biofill is guaranteed to be inactive
4044 if (test_bit(R5_UPTODATE
, &dev
->flags
) && dev
->toread
&&
4045 !test_bit(STRIPE_BIOFILL_RUN
, &sh
->state
))
4046 set_bit(R5_Wantfill
, &dev
->flags
);
4048 /* now count some things */
4049 if (test_bit(R5_LOCKED
, &dev
->flags
))
4051 if (test_bit(R5_UPTODATE
, &dev
->flags
))
4053 if (test_bit(R5_Wantcompute
, &dev
->flags
)) {
4055 BUG_ON(s
->compute
> 2);
4058 if (test_bit(R5_Wantfill
, &dev
->flags
))
4060 else if (dev
->toread
)
4064 if (!test_bit(R5_OVERWRITE
, &dev
->flags
))
4069 /* Prefer to use the replacement for reads, but only
4070 * if it is recovered enough and has no bad blocks.
4072 rdev
= rcu_dereference(conf
->disks
[i
].replacement
);
4073 if (rdev
&& !test_bit(Faulty
, &rdev
->flags
) &&
4074 rdev
->recovery_offset
>= sh
->sector
+ STRIPE_SECTORS
&&
4075 !is_badblock(rdev
, sh
->sector
, STRIPE_SECTORS
,
4076 &first_bad
, &bad_sectors
))
4077 set_bit(R5_ReadRepl
, &dev
->flags
);
4079 if (rdev
&& !test_bit(Faulty
, &rdev
->flags
))
4080 set_bit(R5_NeedReplace
, &dev
->flags
);
4082 clear_bit(R5_NeedReplace
, &dev
->flags
);
4083 rdev
= rcu_dereference(conf
->disks
[i
].rdev
);
4084 clear_bit(R5_ReadRepl
, &dev
->flags
);
4086 if (rdev
&& test_bit(Faulty
, &rdev
->flags
))
4089 is_bad
= is_badblock(rdev
, sh
->sector
, STRIPE_SECTORS
,
4090 &first_bad
, &bad_sectors
);
4091 if (s
->blocked_rdev
== NULL
4092 && (test_bit(Blocked
, &rdev
->flags
)
4095 set_bit(BlockedBadBlocks
,
4097 s
->blocked_rdev
= rdev
;
4098 atomic_inc(&rdev
->nr_pending
);
4101 clear_bit(R5_Insync
, &dev
->flags
);
4105 /* also not in-sync */
4106 if (!test_bit(WriteErrorSeen
, &rdev
->flags
) &&
4107 test_bit(R5_UPTODATE
, &dev
->flags
)) {
4108 /* treat as in-sync, but with a read error
4109 * which we can now try to correct
4111 set_bit(R5_Insync
, &dev
->flags
);
4112 set_bit(R5_ReadError
, &dev
->flags
);
4114 } else if (test_bit(In_sync
, &rdev
->flags
))
4115 set_bit(R5_Insync
, &dev
->flags
);
4116 else if (sh
->sector
+ STRIPE_SECTORS
<= rdev
->recovery_offset
)
4117 /* in sync if before recovery_offset */
4118 set_bit(R5_Insync
, &dev
->flags
);
4119 else if (test_bit(R5_UPTODATE
, &dev
->flags
) &&
4120 test_bit(R5_Expanded
, &dev
->flags
))
4121 /* If we've reshaped into here, we assume it is Insync.
4122 * We will shortly update recovery_offset to make
4125 set_bit(R5_Insync
, &dev
->flags
);
4127 if (test_bit(R5_WriteError
, &dev
->flags
)) {
4128 /* This flag does not apply to '.replacement'
4129 * only to .rdev, so make sure to check that*/
4130 struct md_rdev
*rdev2
= rcu_dereference(
4131 conf
->disks
[i
].rdev
);
4133 clear_bit(R5_Insync
, &dev
->flags
);
4134 if (rdev2
&& !test_bit(Faulty
, &rdev2
->flags
)) {
4135 s
->handle_bad_blocks
= 1;
4136 atomic_inc(&rdev2
->nr_pending
);
4138 clear_bit(R5_WriteError
, &dev
->flags
);
4140 if (test_bit(R5_MadeGood
, &dev
->flags
)) {
4141 /* This flag does not apply to '.replacement'
4142 * only to .rdev, so make sure to check that*/
4143 struct md_rdev
*rdev2
= rcu_dereference(
4144 conf
->disks
[i
].rdev
);
4145 if (rdev2
&& !test_bit(Faulty
, &rdev2
->flags
)) {
4146 s
->handle_bad_blocks
= 1;
4147 atomic_inc(&rdev2
->nr_pending
);
4149 clear_bit(R5_MadeGood
, &dev
->flags
);
4151 if (test_bit(R5_MadeGoodRepl
, &dev
->flags
)) {
4152 struct md_rdev
*rdev2
= rcu_dereference(
4153 conf
->disks
[i
].replacement
);
4154 if (rdev2
&& !test_bit(Faulty
, &rdev2
->flags
)) {
4155 s
->handle_bad_blocks
= 1;
4156 atomic_inc(&rdev2
->nr_pending
);
4158 clear_bit(R5_MadeGoodRepl
, &dev
->flags
);
4160 if (!test_bit(R5_Insync
, &dev
->flags
)) {
4161 /* The ReadError flag will just be confusing now */
4162 clear_bit(R5_ReadError
, &dev
->flags
);
4163 clear_bit(R5_ReWrite
, &dev
->flags
);
4165 if (test_bit(R5_ReadError
, &dev
->flags
))
4166 clear_bit(R5_Insync
, &dev
->flags
);
4167 if (!test_bit(R5_Insync
, &dev
->flags
)) {
4169 s
->failed_num
[s
->failed
] = i
;
4171 if (rdev
&& !test_bit(Faulty
, &rdev
->flags
))
4175 if (test_bit(STRIPE_SYNCING
, &sh
->state
)) {
4176 /* If there is a failed device being replaced,
4177 * we must be recovering.
4178 * else if we are after recovery_cp, we must be syncing
4179 * else if MD_RECOVERY_REQUESTED is set, we also are syncing.
4180 * else we can only be replacing
4181 * sync and recovery both need to read all devices, and so
4182 * use the same flag.
4185 sh
->sector
>= conf
->mddev
->recovery_cp
||
4186 test_bit(MD_RECOVERY_REQUESTED
, &(conf
->mddev
->recovery
)))
4194 static int clear_batch_ready(struct stripe_head
*sh
)
4196 /* Return '1' if this is a member of batch, or
4197 * '0' if it is a lone stripe or a head which can now be
4200 struct stripe_head
*tmp
;
4201 if (!test_and_clear_bit(STRIPE_BATCH_READY
, &sh
->state
))
4202 return (sh
->batch_head
&& sh
->batch_head
!= sh
);
4203 spin_lock(&sh
->stripe_lock
);
4204 if (!sh
->batch_head
) {
4205 spin_unlock(&sh
->stripe_lock
);
4210 * this stripe could be added to a batch list before we check
4211 * BATCH_READY, skips it
4213 if (sh
->batch_head
!= sh
) {
4214 spin_unlock(&sh
->stripe_lock
);
4217 spin_lock(&sh
->batch_lock
);
4218 list_for_each_entry(tmp
, &sh
->batch_list
, batch_list
)
4219 clear_bit(STRIPE_BATCH_READY
, &tmp
->state
);
4220 spin_unlock(&sh
->batch_lock
);
4221 spin_unlock(&sh
->stripe_lock
);
4224 * BATCH_READY is cleared, no new stripes can be added.
4225 * batch_list can be accessed without lock
4230 static void break_stripe_batch_list(struct stripe_head
*head_sh
,
4231 unsigned long handle_flags
)
4233 struct stripe_head
*sh
, *next
;
4237 list_for_each_entry_safe(sh
, next
, &head_sh
->batch_list
, batch_list
) {
4239 list_del_init(&sh
->batch_list
);
4241 WARN_ON_ONCE(sh
->state
& ((1 << STRIPE_ACTIVE
) |
4242 (1 << STRIPE_SYNCING
) |
4243 (1 << STRIPE_REPLACED
) |
4244 (1 << STRIPE_PREREAD_ACTIVE
) |
4245 (1 << STRIPE_DELAYED
) |
4246 (1 << STRIPE_BIT_DELAY
) |
4247 (1 << STRIPE_FULL_WRITE
) |
4248 (1 << STRIPE_BIOFILL_RUN
) |
4249 (1 << STRIPE_COMPUTE_RUN
) |
4250 (1 << STRIPE_OPS_REQ_PENDING
) |
4251 (1 << STRIPE_DISCARD
) |
4252 (1 << STRIPE_BATCH_READY
) |
4253 (1 << STRIPE_BATCH_ERR
) |
4254 (1 << STRIPE_BITMAP_PENDING
)));
4255 WARN_ON_ONCE(head_sh
->state
& ((1 << STRIPE_DISCARD
) |
4256 (1 << STRIPE_REPLACED
)));
4258 set_mask_bits(&sh
->state
, ~(STRIPE_EXPAND_SYNC_FLAGS
|
4259 (1 << STRIPE_DEGRADED
)),
4260 head_sh
->state
& (1 << STRIPE_INSYNC
));
4262 sh
->check_state
= head_sh
->check_state
;
4263 sh
->reconstruct_state
= head_sh
->reconstruct_state
;
4264 for (i
= 0; i
< sh
->disks
; i
++) {
4265 if (test_and_clear_bit(R5_Overlap
, &sh
->dev
[i
].flags
))
4267 sh
->dev
[i
].flags
= head_sh
->dev
[i
].flags
&
4268 (~((1 << R5_WriteError
) | (1 << R5_Overlap
)));
4270 spin_lock_irq(&sh
->stripe_lock
);
4271 sh
->batch_head
= NULL
;
4272 spin_unlock_irq(&sh
->stripe_lock
);
4273 if (handle_flags
== 0 ||
4274 sh
->state
& handle_flags
)
4275 set_bit(STRIPE_HANDLE
, &sh
->state
);
4276 raid5_release_stripe(sh
);
4278 spin_lock_irq(&head_sh
->stripe_lock
);
4279 head_sh
->batch_head
= NULL
;
4280 spin_unlock_irq(&head_sh
->stripe_lock
);
4281 for (i
= 0; i
< head_sh
->disks
; i
++)
4282 if (test_and_clear_bit(R5_Overlap
, &head_sh
->dev
[i
].flags
))
4284 if (head_sh
->state
& handle_flags
)
4285 set_bit(STRIPE_HANDLE
, &head_sh
->state
);
4288 wake_up(&head_sh
->raid_conf
->wait_for_overlap
);
4291 static void handle_stripe(struct stripe_head
*sh
)
4293 struct stripe_head_state s
;
4294 struct r5conf
*conf
= sh
->raid_conf
;
4297 int disks
= sh
->disks
;
4298 struct r5dev
*pdev
, *qdev
;
4300 clear_bit(STRIPE_HANDLE
, &sh
->state
);
4301 if (test_and_set_bit_lock(STRIPE_ACTIVE
, &sh
->state
)) {
4302 /* already being handled, ensure it gets handled
4303 * again when current action finishes */
4304 set_bit(STRIPE_HANDLE
, &sh
->state
);
4308 if (clear_batch_ready(sh
) ) {
4309 clear_bit_unlock(STRIPE_ACTIVE
, &sh
->state
);
4313 if (test_and_clear_bit(STRIPE_BATCH_ERR
, &sh
->state
))
4314 break_stripe_batch_list(sh
, 0);
4316 if (test_bit(STRIPE_SYNC_REQUESTED
, &sh
->state
) && !sh
->batch_head
) {
4317 spin_lock(&sh
->stripe_lock
);
4318 /* Cannot process 'sync' concurrently with 'discard' */
4319 if (!test_bit(STRIPE_DISCARD
, &sh
->state
) &&
4320 test_and_clear_bit(STRIPE_SYNC_REQUESTED
, &sh
->state
)) {
4321 set_bit(STRIPE_SYNCING
, &sh
->state
);
4322 clear_bit(STRIPE_INSYNC
, &sh
->state
);
4323 clear_bit(STRIPE_REPLACED
, &sh
->state
);
4325 spin_unlock(&sh
->stripe_lock
);
4327 clear_bit(STRIPE_DELAYED
, &sh
->state
);
4329 pr_debug("handling stripe %llu, state=%#lx cnt=%d, "
4330 "pd_idx=%d, qd_idx=%d\n, check:%d, reconstruct:%d\n",
4331 (unsigned long long)sh
->sector
, sh
->state
,
4332 atomic_read(&sh
->count
), sh
->pd_idx
, sh
->qd_idx
,
4333 sh
->check_state
, sh
->reconstruct_state
);
4335 analyse_stripe(sh
, &s
);
4337 if (test_bit(STRIPE_LOG_TRAPPED
, &sh
->state
))
4340 if (s
.handle_bad_blocks
) {
4341 set_bit(STRIPE_HANDLE
, &sh
->state
);
4345 if (unlikely(s
.blocked_rdev
)) {
4346 if (s
.syncing
|| s
.expanding
|| s
.expanded
||
4347 s
.replacing
|| s
.to_write
|| s
.written
) {
4348 set_bit(STRIPE_HANDLE
, &sh
->state
);
4351 /* There is nothing for the blocked_rdev to block */
4352 rdev_dec_pending(s
.blocked_rdev
, conf
->mddev
);
4353 s
.blocked_rdev
= NULL
;
4356 if (s
.to_fill
&& !test_bit(STRIPE_BIOFILL_RUN
, &sh
->state
)) {
4357 set_bit(STRIPE_OP_BIOFILL
, &s
.ops_request
);
4358 set_bit(STRIPE_BIOFILL_RUN
, &sh
->state
);
4361 pr_debug("locked=%d uptodate=%d to_read=%d"
4362 " to_write=%d failed=%d failed_num=%d,%d\n",
4363 s
.locked
, s
.uptodate
, s
.to_read
, s
.to_write
, s
.failed
,
4364 s
.failed_num
[0], s
.failed_num
[1]);
4365 /* check if the array has lost more than max_degraded devices and,
4366 * if so, some requests might need to be failed.
4368 if (s
.failed
> conf
->max_degraded
|| s
.log_failed
) {
4369 sh
->check_state
= 0;
4370 sh
->reconstruct_state
= 0;
4371 break_stripe_batch_list(sh
, 0);
4372 if (s
.to_read
+s
.to_write
+s
.written
)
4373 handle_failed_stripe(conf
, sh
, &s
, disks
, &s
.return_bi
);
4374 if (s
.syncing
+ s
.replacing
)
4375 handle_failed_sync(conf
, sh
, &s
);
4378 /* Now we check to see if any write operations have recently
4382 if (sh
->reconstruct_state
== reconstruct_state_prexor_drain_result
)
4384 if (sh
->reconstruct_state
== reconstruct_state_drain_result
||
4385 sh
->reconstruct_state
== reconstruct_state_prexor_drain_result
) {
4386 sh
->reconstruct_state
= reconstruct_state_idle
;
4388 /* All the 'written' buffers and the parity block are ready to
4389 * be written back to disk
4391 BUG_ON(!test_bit(R5_UPTODATE
, &sh
->dev
[sh
->pd_idx
].flags
) &&
4392 !test_bit(R5_Discard
, &sh
->dev
[sh
->pd_idx
].flags
));
4393 BUG_ON(sh
->qd_idx
>= 0 &&
4394 !test_bit(R5_UPTODATE
, &sh
->dev
[sh
->qd_idx
].flags
) &&
4395 !test_bit(R5_Discard
, &sh
->dev
[sh
->qd_idx
].flags
));
4396 for (i
= disks
; i
--; ) {
4397 struct r5dev
*dev
= &sh
->dev
[i
];
4398 if (test_bit(R5_LOCKED
, &dev
->flags
) &&
4399 (i
== sh
->pd_idx
|| i
== sh
->qd_idx
||
4401 pr_debug("Writing block %d\n", i
);
4402 set_bit(R5_Wantwrite
, &dev
->flags
);
4407 if (!test_bit(R5_Insync
, &dev
->flags
) ||
4408 ((i
== sh
->pd_idx
|| i
== sh
->qd_idx
) &&
4410 set_bit(STRIPE_INSYNC
, &sh
->state
);
4413 if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
4414 s
.dec_preread_active
= 1;
4418 * might be able to return some write requests if the parity blocks
4419 * are safe, or on a failed drive
4421 pdev
= &sh
->dev
[sh
->pd_idx
];
4422 s
.p_failed
= (s
.failed
>= 1 && s
.failed_num
[0] == sh
->pd_idx
)
4423 || (s
.failed
>= 2 && s
.failed_num
[1] == sh
->pd_idx
);
4424 qdev
= &sh
->dev
[sh
->qd_idx
];
4425 s
.q_failed
= (s
.failed
>= 1 && s
.failed_num
[0] == sh
->qd_idx
)
4426 || (s
.failed
>= 2 && s
.failed_num
[1] == sh
->qd_idx
)
4430 (s
.p_failed
|| ((test_bit(R5_Insync
, &pdev
->flags
)
4431 && !test_bit(R5_LOCKED
, &pdev
->flags
)
4432 && (test_bit(R5_UPTODATE
, &pdev
->flags
) ||
4433 test_bit(R5_Discard
, &pdev
->flags
))))) &&
4434 (s
.q_failed
|| ((test_bit(R5_Insync
, &qdev
->flags
)
4435 && !test_bit(R5_LOCKED
, &qdev
->flags
)
4436 && (test_bit(R5_UPTODATE
, &qdev
->flags
) ||
4437 test_bit(R5_Discard
, &qdev
->flags
))))))
4438 handle_stripe_clean_event(conf
, sh
, disks
, &s
.return_bi
);
4440 /* Now we might consider reading some blocks, either to check/generate
4441 * parity, or to satisfy requests
4442 * or to load a block that is being partially written.
4444 if (s
.to_read
|| s
.non_overwrite
4445 || (conf
->level
== 6 && s
.to_write
&& s
.failed
)
4446 || (s
.syncing
&& (s
.uptodate
+ s
.compute
< disks
))
4449 handle_stripe_fill(sh
, &s
, disks
);
4451 /* Now to consider new write requests and what else, if anything
4452 * should be read. We do not handle new writes when:
4453 * 1/ A 'write' operation (copy+xor) is already in flight.
4454 * 2/ A 'check' operation is in flight, as it may clobber the parity
4457 if (s
.to_write
&& !sh
->reconstruct_state
&& !sh
->check_state
)
4458 handle_stripe_dirtying(conf
, sh
, &s
, disks
);
4460 /* maybe we need to check and possibly fix the parity for this stripe
4461 * Any reads will already have been scheduled, so we just see if enough
4462 * data is available. The parity check is held off while parity
4463 * dependent operations are in flight.
4465 if (sh
->check_state
||
4466 (s
.syncing
&& s
.locked
== 0 &&
4467 !test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
) &&
4468 !test_bit(STRIPE_INSYNC
, &sh
->state
))) {
4469 if (conf
->level
== 6)
4470 handle_parity_checks6(conf
, sh
, &s
, disks
);
4472 handle_parity_checks5(conf
, sh
, &s
, disks
);
4475 if ((s
.replacing
|| s
.syncing
) && s
.locked
== 0
4476 && !test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
)
4477 && !test_bit(STRIPE_REPLACED
, &sh
->state
)) {
4478 /* Write out to replacement devices where possible */
4479 for (i
= 0; i
< conf
->raid_disks
; i
++)
4480 if (test_bit(R5_NeedReplace
, &sh
->dev
[i
].flags
)) {
4481 WARN_ON(!test_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
));
4482 set_bit(R5_WantReplace
, &sh
->dev
[i
].flags
);
4483 set_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
4487 set_bit(STRIPE_INSYNC
, &sh
->state
);
4488 set_bit(STRIPE_REPLACED
, &sh
->state
);
4490 if ((s
.syncing
|| s
.replacing
) && s
.locked
== 0 &&
4491 !test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
) &&
4492 test_bit(STRIPE_INSYNC
, &sh
->state
)) {
4493 md_done_sync(conf
->mddev
, STRIPE_SECTORS
, 1);
4494 clear_bit(STRIPE_SYNCING
, &sh
->state
);
4495 if (test_and_clear_bit(R5_Overlap
, &sh
->dev
[sh
->pd_idx
].flags
))
4496 wake_up(&conf
->wait_for_overlap
);
4499 /* If the failed drives are just a ReadError, then we might need
4500 * to progress the repair/check process
4502 if (s
.failed
<= conf
->max_degraded
&& !conf
->mddev
->ro
)
4503 for (i
= 0; i
< s
.failed
; i
++) {
4504 struct r5dev
*dev
= &sh
->dev
[s
.failed_num
[i
]];
4505 if (test_bit(R5_ReadError
, &dev
->flags
)
4506 && !test_bit(R5_LOCKED
, &dev
->flags
)
4507 && test_bit(R5_UPTODATE
, &dev
->flags
)
4509 if (!test_bit(R5_ReWrite
, &dev
->flags
)) {
4510 set_bit(R5_Wantwrite
, &dev
->flags
);
4511 set_bit(R5_ReWrite
, &dev
->flags
);
4512 set_bit(R5_LOCKED
, &dev
->flags
);
4515 /* let's read it back */
4516 set_bit(R5_Wantread
, &dev
->flags
);
4517 set_bit(R5_LOCKED
, &dev
->flags
);
4523 /* Finish reconstruct operations initiated by the expansion process */
4524 if (sh
->reconstruct_state
== reconstruct_state_result
) {
4525 struct stripe_head
*sh_src
4526 = raid5_get_active_stripe(conf
, sh
->sector
, 1, 1, 1);
4527 if (sh_src
&& test_bit(STRIPE_EXPAND_SOURCE
, &sh_src
->state
)) {
4528 /* sh cannot be written until sh_src has been read.
4529 * so arrange for sh to be delayed a little
4531 set_bit(STRIPE_DELAYED
, &sh
->state
);
4532 set_bit(STRIPE_HANDLE
, &sh
->state
);
4533 if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE
,
4535 atomic_inc(&conf
->preread_active_stripes
);
4536 raid5_release_stripe(sh_src
);
4540 raid5_release_stripe(sh_src
);
4542 sh
->reconstruct_state
= reconstruct_state_idle
;
4543 clear_bit(STRIPE_EXPANDING
, &sh
->state
);
4544 for (i
= conf
->raid_disks
; i
--; ) {
4545 set_bit(R5_Wantwrite
, &sh
->dev
[i
].flags
);
4546 set_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
4551 if (s
.expanded
&& test_bit(STRIPE_EXPANDING
, &sh
->state
) &&
4552 !sh
->reconstruct_state
) {
4553 /* Need to write out all blocks after computing parity */
4554 sh
->disks
= conf
->raid_disks
;
4555 stripe_set_idx(sh
->sector
, conf
, 0, sh
);
4556 schedule_reconstruction(sh
, &s
, 1, 1);
4557 } else if (s
.expanded
&& !sh
->reconstruct_state
&& s
.locked
== 0) {
4558 clear_bit(STRIPE_EXPAND_READY
, &sh
->state
);
4559 atomic_dec(&conf
->reshape_stripes
);
4560 wake_up(&conf
->wait_for_overlap
);
4561 md_done_sync(conf
->mddev
, STRIPE_SECTORS
, 1);
4564 if (s
.expanding
&& s
.locked
== 0 &&
4565 !test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
))
4566 handle_stripe_expansion(conf
, sh
);
4569 /* wait for this device to become unblocked */
4570 if (unlikely(s
.blocked_rdev
)) {
4571 if (conf
->mddev
->external
)
4572 md_wait_for_blocked_rdev(s
.blocked_rdev
,
4575 /* Internal metadata will immediately
4576 * be written by raid5d, so we don't
4577 * need to wait here.
4579 rdev_dec_pending(s
.blocked_rdev
,
4583 if (s
.handle_bad_blocks
)
4584 for (i
= disks
; i
--; ) {
4585 struct md_rdev
*rdev
;
4586 struct r5dev
*dev
= &sh
->dev
[i
];
4587 if (test_and_clear_bit(R5_WriteError
, &dev
->flags
)) {
4588 /* We own a safe reference to the rdev */
4589 rdev
= conf
->disks
[i
].rdev
;
4590 if (!rdev_set_badblocks(rdev
, sh
->sector
,
4592 md_error(conf
->mddev
, rdev
);
4593 rdev_dec_pending(rdev
, conf
->mddev
);
4595 if (test_and_clear_bit(R5_MadeGood
, &dev
->flags
)) {
4596 rdev
= conf
->disks
[i
].rdev
;
4597 rdev_clear_badblocks(rdev
, sh
->sector
,
4599 rdev_dec_pending(rdev
, conf
->mddev
);
4601 if (test_and_clear_bit(R5_MadeGoodRepl
, &dev
->flags
)) {
4602 rdev
= conf
->disks
[i
].replacement
;
4604 /* rdev have been moved down */
4605 rdev
= conf
->disks
[i
].rdev
;
4606 rdev_clear_badblocks(rdev
, sh
->sector
,
4608 rdev_dec_pending(rdev
, conf
->mddev
);
4613 raid_run_ops(sh
, s
.ops_request
);
4617 if (s
.dec_preread_active
) {
4618 /* We delay this until after ops_run_io so that if make_request
4619 * is waiting on a flush, it won't continue until the writes
4620 * have actually been submitted.
4622 atomic_dec(&conf
->preread_active_stripes
);
4623 if (atomic_read(&conf
->preread_active_stripes
) <
4625 md_wakeup_thread(conf
->mddev
->thread
);
4628 if (!bio_list_empty(&s
.return_bi
)) {
4629 if (test_bit(MD_CHANGE_PENDING
, &conf
->mddev
->flags
)) {
4630 spin_lock_irq(&conf
->device_lock
);
4631 bio_list_merge(&conf
->return_bi
, &s
.return_bi
);
4632 spin_unlock_irq(&conf
->device_lock
);
4633 md_wakeup_thread(conf
->mddev
->thread
);
4635 return_io(&s
.return_bi
);
4638 clear_bit_unlock(STRIPE_ACTIVE
, &sh
->state
);
4641 static void raid5_activate_delayed(struct r5conf
*conf
)
4643 if (atomic_read(&conf
->preread_active_stripes
) < IO_THRESHOLD
) {
4644 while (!list_empty(&conf
->delayed_list
)) {
4645 struct list_head
*l
= conf
->delayed_list
.next
;
4646 struct stripe_head
*sh
;
4647 sh
= list_entry(l
, struct stripe_head
, lru
);
4649 clear_bit(STRIPE_DELAYED
, &sh
->state
);
4650 if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
4651 atomic_inc(&conf
->preread_active_stripes
);
4652 list_add_tail(&sh
->lru
, &conf
->hold_list
);
4653 raid5_wakeup_stripe_thread(sh
);
4658 static void activate_bit_delay(struct r5conf
*conf
,
4659 struct list_head
*temp_inactive_list
)
4661 /* device_lock is held */
4662 struct list_head head
;
4663 list_add(&head
, &conf
->bitmap_list
);
4664 list_del_init(&conf
->bitmap_list
);
4665 while (!list_empty(&head
)) {
4666 struct stripe_head
*sh
= list_entry(head
.next
, struct stripe_head
, lru
);
4668 list_del_init(&sh
->lru
);
4669 atomic_inc(&sh
->count
);
4670 hash
= sh
->hash_lock_index
;
4671 __release_stripe(conf
, sh
, &temp_inactive_list
[hash
]);
4675 static int raid5_congested(struct mddev
*mddev
, int bits
)
4677 struct r5conf
*conf
= mddev
->private;
4679 /* No difference between reads and writes. Just check
4680 * how busy the stripe_cache is
4683 if (test_bit(R5_INACTIVE_BLOCKED
, &conf
->cache_state
))
4687 if (atomic_read(&conf
->empty_inactive_list_nr
))
4693 static int in_chunk_boundary(struct mddev
*mddev
, struct bio
*bio
)
4695 struct r5conf
*conf
= mddev
->private;
4696 sector_t sector
= bio
->bi_iter
.bi_sector
+ get_start_sect(bio
->bi_bdev
);
4697 unsigned int chunk_sectors
;
4698 unsigned int bio_sectors
= bio_sectors(bio
);
4700 chunk_sectors
= min(conf
->chunk_sectors
, conf
->prev_chunk_sectors
);
4701 return chunk_sectors
>=
4702 ((sector
& (chunk_sectors
- 1)) + bio_sectors
);
4706 * add bio to the retry LIFO ( in O(1) ... we are in interrupt )
4707 * later sampled by raid5d.
4709 static void add_bio_to_retry(struct bio
*bi
,struct r5conf
*conf
)
4711 unsigned long flags
;
4713 spin_lock_irqsave(&conf
->device_lock
, flags
);
4715 bi
->bi_next
= conf
->retry_read_aligned_list
;
4716 conf
->retry_read_aligned_list
= bi
;
4718 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
4719 md_wakeup_thread(conf
->mddev
->thread
);
4722 static struct bio
*remove_bio_from_retry(struct r5conf
*conf
)
4726 bi
= conf
->retry_read_aligned
;
4728 conf
->retry_read_aligned
= NULL
;
4731 bi
= conf
->retry_read_aligned_list
;
4733 conf
->retry_read_aligned_list
= bi
->bi_next
;
4736 * this sets the active strip count to 1 and the processed
4737 * strip count to zero (upper 8 bits)
4739 raid5_set_bi_stripes(bi
, 1); /* biased count of active stripes */
4746 * The "raid5_align_endio" should check if the read succeeded and if it
4747 * did, call bio_endio on the original bio (having bio_put the new bio
4749 * If the read failed..
4751 static void raid5_align_endio(struct bio
*bi
)
4753 struct bio
* raid_bi
= bi
->bi_private
;
4754 struct mddev
*mddev
;
4755 struct r5conf
*conf
;
4756 struct md_rdev
*rdev
;
4757 int error
= bi
->bi_error
;
4761 rdev
= (void*)raid_bi
->bi_next
;
4762 raid_bi
->bi_next
= NULL
;
4763 mddev
= rdev
->mddev
;
4764 conf
= mddev
->private;
4766 rdev_dec_pending(rdev
, conf
->mddev
);
4769 trace_block_bio_complete(bdev_get_queue(raid_bi
->bi_bdev
),
4772 if (atomic_dec_and_test(&conf
->active_aligned_reads
))
4773 wake_up(&conf
->wait_for_quiescent
);
4777 pr_debug("raid5_align_endio : io error...handing IO for a retry\n");
4779 add_bio_to_retry(raid_bi
, conf
);
4782 static int raid5_read_one_chunk(struct mddev
*mddev
, struct bio
*raid_bio
)
4784 struct r5conf
*conf
= mddev
->private;
4786 struct bio
* align_bi
;
4787 struct md_rdev
*rdev
;
4788 sector_t end_sector
;
4790 if (!in_chunk_boundary(mddev
, raid_bio
)) {
4791 pr_debug("%s: non aligned\n", __func__
);
4795 * use bio_clone_mddev to make a copy of the bio
4797 align_bi
= bio_clone_mddev(raid_bio
, GFP_NOIO
, mddev
);
4801 * set bi_end_io to a new function, and set bi_private to the
4804 align_bi
->bi_end_io
= raid5_align_endio
;
4805 align_bi
->bi_private
= raid_bio
;
4809 align_bi
->bi_iter
.bi_sector
=
4810 raid5_compute_sector(conf
, raid_bio
->bi_iter
.bi_sector
,
4813 end_sector
= bio_end_sector(align_bi
);
4815 rdev
= rcu_dereference(conf
->disks
[dd_idx
].replacement
);
4816 if (!rdev
|| test_bit(Faulty
, &rdev
->flags
) ||
4817 rdev
->recovery_offset
< end_sector
) {
4818 rdev
= rcu_dereference(conf
->disks
[dd_idx
].rdev
);
4820 (test_bit(Faulty
, &rdev
->flags
) ||
4821 !(test_bit(In_sync
, &rdev
->flags
) ||
4822 rdev
->recovery_offset
>= end_sector
)))
4829 atomic_inc(&rdev
->nr_pending
);
4831 raid_bio
->bi_next
= (void*)rdev
;
4832 align_bi
->bi_bdev
= rdev
->bdev
;
4833 bio_clear_flag(align_bi
, BIO_SEG_VALID
);
4835 if (is_badblock(rdev
, align_bi
->bi_iter
.bi_sector
,
4836 bio_sectors(align_bi
),
4837 &first_bad
, &bad_sectors
)) {
4839 rdev_dec_pending(rdev
, mddev
);
4843 /* No reshape active, so we can trust rdev->data_offset */
4844 align_bi
->bi_iter
.bi_sector
+= rdev
->data_offset
;
4846 spin_lock_irq(&conf
->device_lock
);
4847 wait_event_lock_irq(conf
->wait_for_quiescent
,
4850 atomic_inc(&conf
->active_aligned_reads
);
4851 spin_unlock_irq(&conf
->device_lock
);
4854 trace_block_bio_remap(bdev_get_queue(align_bi
->bi_bdev
),
4855 align_bi
, disk_devt(mddev
->gendisk
),
4856 raid_bio
->bi_iter
.bi_sector
);
4857 generic_make_request(align_bi
);
4866 static struct bio
*chunk_aligned_read(struct mddev
*mddev
, struct bio
*raid_bio
)
4871 sector_t sector
= raid_bio
->bi_iter
.bi_sector
;
4872 unsigned chunk_sects
= mddev
->chunk_sectors
;
4873 unsigned sectors
= chunk_sects
- (sector
& (chunk_sects
-1));
4875 if (sectors
< bio_sectors(raid_bio
)) {
4876 split
= bio_split(raid_bio
, sectors
, GFP_NOIO
, fs_bio_set
);
4877 bio_chain(split
, raid_bio
);
4881 if (!raid5_read_one_chunk(mddev
, split
)) {
4882 if (split
!= raid_bio
)
4883 generic_make_request(raid_bio
);
4886 } while (split
!= raid_bio
);
4891 /* __get_priority_stripe - get the next stripe to process
4893 * Full stripe writes are allowed to pass preread active stripes up until
4894 * the bypass_threshold is exceeded. In general the bypass_count
4895 * increments when the handle_list is handled before the hold_list; however, it
4896 * will not be incremented when STRIPE_IO_STARTED is sampled set signifying a
4897 * stripe with in flight i/o. The bypass_count will be reset when the
4898 * head of the hold_list has changed, i.e. the head was promoted to the
4901 static struct stripe_head
*__get_priority_stripe(struct r5conf
*conf
, int group
)
4903 struct stripe_head
*sh
= NULL
, *tmp
;
4904 struct list_head
*handle_list
= NULL
;
4905 struct r5worker_group
*wg
= NULL
;
4907 if (conf
->worker_cnt_per_group
== 0) {
4908 handle_list
= &conf
->handle_list
;
4909 } else if (group
!= ANY_GROUP
) {
4910 handle_list
= &conf
->worker_groups
[group
].handle_list
;
4911 wg
= &conf
->worker_groups
[group
];
4914 for (i
= 0; i
< conf
->group_cnt
; i
++) {
4915 handle_list
= &conf
->worker_groups
[i
].handle_list
;
4916 wg
= &conf
->worker_groups
[i
];
4917 if (!list_empty(handle_list
))
4922 pr_debug("%s: handle: %s hold: %s full_writes: %d bypass_count: %d\n",
4924 list_empty(handle_list
) ? "empty" : "busy",
4925 list_empty(&conf
->hold_list
) ? "empty" : "busy",
4926 atomic_read(&conf
->pending_full_writes
), conf
->bypass_count
);
4928 if (!list_empty(handle_list
)) {
4929 sh
= list_entry(handle_list
->next
, typeof(*sh
), lru
);
4931 if (list_empty(&conf
->hold_list
))
4932 conf
->bypass_count
= 0;
4933 else if (!test_bit(STRIPE_IO_STARTED
, &sh
->state
)) {
4934 if (conf
->hold_list
.next
== conf
->last_hold
)
4935 conf
->bypass_count
++;
4937 conf
->last_hold
= conf
->hold_list
.next
;
4938 conf
->bypass_count
-= conf
->bypass_threshold
;
4939 if (conf
->bypass_count
< 0)
4940 conf
->bypass_count
= 0;
4943 } else if (!list_empty(&conf
->hold_list
) &&
4944 ((conf
->bypass_threshold
&&
4945 conf
->bypass_count
> conf
->bypass_threshold
) ||
4946 atomic_read(&conf
->pending_full_writes
) == 0)) {
4948 list_for_each_entry(tmp
, &conf
->hold_list
, lru
) {
4949 if (conf
->worker_cnt_per_group
== 0 ||
4950 group
== ANY_GROUP
||
4951 !cpu_online(tmp
->cpu
) ||
4952 cpu_to_group(tmp
->cpu
) == group
) {
4959 conf
->bypass_count
-= conf
->bypass_threshold
;
4960 if (conf
->bypass_count
< 0)
4961 conf
->bypass_count
= 0;
4973 list_del_init(&sh
->lru
);
4974 BUG_ON(atomic_inc_return(&sh
->count
) != 1);
4978 struct raid5_plug_cb
{
4979 struct blk_plug_cb cb
;
4980 struct list_head list
;
4981 struct list_head temp_inactive_list
[NR_STRIPE_HASH_LOCKS
];
4984 static void raid5_unplug(struct blk_plug_cb
*blk_cb
, bool from_schedule
)
4986 struct raid5_plug_cb
*cb
= container_of(
4987 blk_cb
, struct raid5_plug_cb
, cb
);
4988 struct stripe_head
*sh
;
4989 struct mddev
*mddev
= cb
->cb
.data
;
4990 struct r5conf
*conf
= mddev
->private;
4994 if (cb
->list
.next
&& !list_empty(&cb
->list
)) {
4995 spin_lock_irq(&conf
->device_lock
);
4996 while (!list_empty(&cb
->list
)) {
4997 sh
= list_first_entry(&cb
->list
, struct stripe_head
, lru
);
4998 list_del_init(&sh
->lru
);
5000 * avoid race release_stripe_plug() sees
5001 * STRIPE_ON_UNPLUG_LIST clear but the stripe
5002 * is still in our list
5004 smp_mb__before_atomic();
5005 clear_bit(STRIPE_ON_UNPLUG_LIST
, &sh
->state
);
5007 * STRIPE_ON_RELEASE_LIST could be set here. In that
5008 * case, the count is always > 1 here
5010 hash
= sh
->hash_lock_index
;
5011 __release_stripe(conf
, sh
, &cb
->temp_inactive_list
[hash
]);
5014 spin_unlock_irq(&conf
->device_lock
);
5016 release_inactive_stripe_list(conf
, cb
->temp_inactive_list
,
5017 NR_STRIPE_HASH_LOCKS
);
5019 trace_block_unplug(mddev
->queue
, cnt
, !from_schedule
);
5023 static void release_stripe_plug(struct mddev
*mddev
,
5024 struct stripe_head
*sh
)
5026 struct blk_plug_cb
*blk_cb
= blk_check_plugged(
5027 raid5_unplug
, mddev
,
5028 sizeof(struct raid5_plug_cb
));
5029 struct raid5_plug_cb
*cb
;
5032 raid5_release_stripe(sh
);
5036 cb
= container_of(blk_cb
, struct raid5_plug_cb
, cb
);
5038 if (cb
->list
.next
== NULL
) {
5040 INIT_LIST_HEAD(&cb
->list
);
5041 for (i
= 0; i
< NR_STRIPE_HASH_LOCKS
; i
++)
5042 INIT_LIST_HEAD(cb
->temp_inactive_list
+ i
);
5045 if (!test_and_set_bit(STRIPE_ON_UNPLUG_LIST
, &sh
->state
))
5046 list_add_tail(&sh
->lru
, &cb
->list
);
5048 raid5_release_stripe(sh
);
5051 static void make_discard_request(struct mddev
*mddev
, struct bio
*bi
)
5053 struct r5conf
*conf
= mddev
->private;
5054 sector_t logical_sector
, last_sector
;
5055 struct stripe_head
*sh
;
5059 if (mddev
->reshape_position
!= MaxSector
)
5060 /* Skip discard while reshape is happening */
5063 logical_sector
= bi
->bi_iter
.bi_sector
& ~((sector_t
)STRIPE_SECTORS
-1);
5064 last_sector
= bi
->bi_iter
.bi_sector
+ (bi
->bi_iter
.bi_size
>>9);
5067 bi
->bi_phys_segments
= 1; /* over-loaded to count active stripes */
5069 stripe_sectors
= conf
->chunk_sectors
*
5070 (conf
->raid_disks
- conf
->max_degraded
);
5071 logical_sector
= DIV_ROUND_UP_SECTOR_T(logical_sector
,
5073 sector_div(last_sector
, stripe_sectors
);
5075 logical_sector
*= conf
->chunk_sectors
;
5076 last_sector
*= conf
->chunk_sectors
;
5078 for (; logical_sector
< last_sector
;
5079 logical_sector
+= STRIPE_SECTORS
) {
5083 sh
= raid5_get_active_stripe(conf
, logical_sector
, 0, 0, 0);
5084 prepare_to_wait(&conf
->wait_for_overlap
, &w
,
5085 TASK_UNINTERRUPTIBLE
);
5086 set_bit(R5_Overlap
, &sh
->dev
[sh
->pd_idx
].flags
);
5087 if (test_bit(STRIPE_SYNCING
, &sh
->state
)) {
5088 raid5_release_stripe(sh
);
5092 clear_bit(R5_Overlap
, &sh
->dev
[sh
->pd_idx
].flags
);
5093 spin_lock_irq(&sh
->stripe_lock
);
5094 for (d
= 0; d
< conf
->raid_disks
; d
++) {
5095 if (d
== sh
->pd_idx
|| d
== sh
->qd_idx
)
5097 if (sh
->dev
[d
].towrite
|| sh
->dev
[d
].toread
) {
5098 set_bit(R5_Overlap
, &sh
->dev
[d
].flags
);
5099 spin_unlock_irq(&sh
->stripe_lock
);
5100 raid5_release_stripe(sh
);
5105 set_bit(STRIPE_DISCARD
, &sh
->state
);
5106 finish_wait(&conf
->wait_for_overlap
, &w
);
5107 sh
->overwrite_disks
= 0;
5108 for (d
= 0; d
< conf
->raid_disks
; d
++) {
5109 if (d
== sh
->pd_idx
|| d
== sh
->qd_idx
)
5111 sh
->dev
[d
].towrite
= bi
;
5112 set_bit(R5_OVERWRITE
, &sh
->dev
[d
].flags
);
5113 raid5_inc_bi_active_stripes(bi
);
5114 sh
->overwrite_disks
++;
5116 spin_unlock_irq(&sh
->stripe_lock
);
5117 if (conf
->mddev
->bitmap
) {
5119 d
< conf
->raid_disks
- conf
->max_degraded
;
5121 bitmap_startwrite(mddev
->bitmap
,
5125 sh
->bm_seq
= conf
->seq_flush
+ 1;
5126 set_bit(STRIPE_BIT_DELAY
, &sh
->state
);
5129 set_bit(STRIPE_HANDLE
, &sh
->state
);
5130 clear_bit(STRIPE_DELAYED
, &sh
->state
);
5131 if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
5132 atomic_inc(&conf
->preread_active_stripes
);
5133 release_stripe_plug(mddev
, sh
);
5136 remaining
= raid5_dec_bi_active_stripes(bi
);
5137 if (remaining
== 0) {
5138 md_write_end(mddev
);
5143 static void make_request(struct mddev
*mddev
, struct bio
* bi
)
5145 struct r5conf
*conf
= mddev
->private;
5147 sector_t new_sector
;
5148 sector_t logical_sector
, last_sector
;
5149 struct stripe_head
*sh
;
5150 const int rw
= bio_data_dir(bi
);
5155 if (unlikely(bi
->bi_rw
& REQ_FLUSH
)) {
5156 int ret
= r5l_handle_flush_request(conf
->log
, bi
);
5160 if (ret
== -ENODEV
) {
5161 md_flush_request(mddev
, bi
);
5164 /* ret == -EAGAIN, fallback */
5167 md_write_start(mddev
, bi
);
5170 * If array is degraded, better not do chunk aligned read because
5171 * later we might have to read it again in order to reconstruct
5172 * data on failed drives.
5174 if (rw
== READ
&& mddev
->degraded
== 0 &&
5175 mddev
->reshape_position
== MaxSector
) {
5176 bi
= chunk_aligned_read(mddev
, bi
);
5181 if (unlikely(bi
->bi_rw
& REQ_DISCARD
)) {
5182 make_discard_request(mddev
, bi
);
5186 logical_sector
= bi
->bi_iter
.bi_sector
& ~((sector_t
)STRIPE_SECTORS
-1);
5187 last_sector
= bio_end_sector(bi
);
5189 bi
->bi_phys_segments
= 1; /* over-loaded to count active stripes */
5191 prepare_to_wait(&conf
->wait_for_overlap
, &w
, TASK_UNINTERRUPTIBLE
);
5192 for (;logical_sector
< last_sector
; logical_sector
+= STRIPE_SECTORS
) {
5198 seq
= read_seqcount_begin(&conf
->gen_lock
);
5201 prepare_to_wait(&conf
->wait_for_overlap
, &w
,
5202 TASK_UNINTERRUPTIBLE
);
5203 if (unlikely(conf
->reshape_progress
!= MaxSector
)) {
5204 /* spinlock is needed as reshape_progress may be
5205 * 64bit on a 32bit platform, and so it might be
5206 * possible to see a half-updated value
5207 * Of course reshape_progress could change after
5208 * the lock is dropped, so once we get a reference
5209 * to the stripe that we think it is, we will have
5212 spin_lock_irq(&conf
->device_lock
);
5213 if (mddev
->reshape_backwards
5214 ? logical_sector
< conf
->reshape_progress
5215 : logical_sector
>= conf
->reshape_progress
) {
5218 if (mddev
->reshape_backwards
5219 ? logical_sector
< conf
->reshape_safe
5220 : logical_sector
>= conf
->reshape_safe
) {
5221 spin_unlock_irq(&conf
->device_lock
);
5227 spin_unlock_irq(&conf
->device_lock
);
5230 new_sector
= raid5_compute_sector(conf
, logical_sector
,
5233 pr_debug("raid456: make_request, sector %llu logical %llu\n",
5234 (unsigned long long)new_sector
,
5235 (unsigned long long)logical_sector
);
5237 sh
= raid5_get_active_stripe(conf
, new_sector
, previous
,
5238 (bi
->bi_rw
&RWA_MASK
), 0);
5240 if (unlikely(previous
)) {
5241 /* expansion might have moved on while waiting for a
5242 * stripe, so we must do the range check again.
5243 * Expansion could still move past after this
5244 * test, but as we are holding a reference to
5245 * 'sh', we know that if that happens,
5246 * STRIPE_EXPANDING will get set and the expansion
5247 * won't proceed until we finish with the stripe.
5250 spin_lock_irq(&conf
->device_lock
);
5251 if (mddev
->reshape_backwards
5252 ? logical_sector
>= conf
->reshape_progress
5253 : logical_sector
< conf
->reshape_progress
)
5254 /* mismatch, need to try again */
5256 spin_unlock_irq(&conf
->device_lock
);
5258 raid5_release_stripe(sh
);
5264 if (read_seqcount_retry(&conf
->gen_lock
, seq
)) {
5265 /* Might have got the wrong stripe_head
5268 raid5_release_stripe(sh
);
5273 logical_sector
>= mddev
->suspend_lo
&&
5274 logical_sector
< mddev
->suspend_hi
) {
5275 raid5_release_stripe(sh
);
5276 /* As the suspend_* range is controlled by
5277 * userspace, we want an interruptible
5280 flush_signals(current
);
5281 prepare_to_wait(&conf
->wait_for_overlap
,
5282 &w
, TASK_INTERRUPTIBLE
);
5283 if (logical_sector
>= mddev
->suspend_lo
&&
5284 logical_sector
< mddev
->suspend_hi
) {
5291 if (test_bit(STRIPE_EXPANDING
, &sh
->state
) ||
5292 !add_stripe_bio(sh
, bi
, dd_idx
, rw
, previous
)) {
5293 /* Stripe is busy expanding or
5294 * add failed due to overlap. Flush everything
5297 md_wakeup_thread(mddev
->thread
);
5298 raid5_release_stripe(sh
);
5303 set_bit(STRIPE_HANDLE
, &sh
->state
);
5304 clear_bit(STRIPE_DELAYED
, &sh
->state
);
5305 if ((!sh
->batch_head
|| sh
== sh
->batch_head
) &&
5306 (bi
->bi_rw
& REQ_SYNC
) &&
5307 !test_and_set_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
5308 atomic_inc(&conf
->preread_active_stripes
);
5309 release_stripe_plug(mddev
, sh
);
5311 /* cannot get stripe for read-ahead, just give-up */
5312 bi
->bi_error
= -EIO
;
5316 finish_wait(&conf
->wait_for_overlap
, &w
);
5318 remaining
= raid5_dec_bi_active_stripes(bi
);
5319 if (remaining
== 0) {
5322 md_write_end(mddev
);
5324 trace_block_bio_complete(bdev_get_queue(bi
->bi_bdev
),
5330 static sector_t
raid5_size(struct mddev
*mddev
, sector_t sectors
, int raid_disks
);
5332 static sector_t
reshape_request(struct mddev
*mddev
, sector_t sector_nr
, int *skipped
)
5334 /* reshaping is quite different to recovery/resync so it is
5335 * handled quite separately ... here.
5337 * On each call to sync_request, we gather one chunk worth of
5338 * destination stripes and flag them as expanding.
5339 * Then we find all the source stripes and request reads.
5340 * As the reads complete, handle_stripe will copy the data
5341 * into the destination stripe and release that stripe.
5343 struct r5conf
*conf
= mddev
->private;
5344 struct stripe_head
*sh
;
5345 sector_t first_sector
, last_sector
;
5346 int raid_disks
= conf
->previous_raid_disks
;
5347 int data_disks
= raid_disks
- conf
->max_degraded
;
5348 int new_data_disks
= conf
->raid_disks
- conf
->max_degraded
;
5351 sector_t writepos
, readpos
, safepos
;
5352 sector_t stripe_addr
;
5353 int reshape_sectors
;
5354 struct list_head stripes
;
5357 if (sector_nr
== 0) {
5358 /* If restarting in the middle, skip the initial sectors */
5359 if (mddev
->reshape_backwards
&&
5360 conf
->reshape_progress
< raid5_size(mddev
, 0, 0)) {
5361 sector_nr
= raid5_size(mddev
, 0, 0)
5362 - conf
->reshape_progress
;
5363 } else if (mddev
->reshape_backwards
&&
5364 conf
->reshape_progress
== MaxSector
) {
5365 /* shouldn't happen, but just in case, finish up.*/
5366 sector_nr
= MaxSector
;
5367 } else if (!mddev
->reshape_backwards
&&
5368 conf
->reshape_progress
> 0)
5369 sector_nr
= conf
->reshape_progress
;
5370 sector_div(sector_nr
, new_data_disks
);
5372 mddev
->curr_resync_completed
= sector_nr
;
5373 sysfs_notify(&mddev
->kobj
, NULL
, "sync_completed");
5380 /* We need to process a full chunk at a time.
5381 * If old and new chunk sizes differ, we need to process the
5385 reshape_sectors
= max(conf
->chunk_sectors
, conf
->prev_chunk_sectors
);
5387 /* We update the metadata at least every 10 seconds, or when
5388 * the data about to be copied would over-write the source of
5389 * the data at the front of the range. i.e. one new_stripe
5390 * along from reshape_progress new_maps to after where
5391 * reshape_safe old_maps to
5393 writepos
= conf
->reshape_progress
;
5394 sector_div(writepos
, new_data_disks
);
5395 readpos
= conf
->reshape_progress
;
5396 sector_div(readpos
, data_disks
);
5397 safepos
= conf
->reshape_safe
;
5398 sector_div(safepos
, data_disks
);
5399 if (mddev
->reshape_backwards
) {
5400 BUG_ON(writepos
< reshape_sectors
);
5401 writepos
-= reshape_sectors
;
5402 readpos
+= reshape_sectors
;
5403 safepos
+= reshape_sectors
;
5405 writepos
+= reshape_sectors
;
5406 /* readpos and safepos are worst-case calculations.
5407 * A negative number is overly pessimistic, and causes
5408 * obvious problems for unsigned storage. So clip to 0.
5410 readpos
-= min_t(sector_t
, reshape_sectors
, readpos
);
5411 safepos
-= min_t(sector_t
, reshape_sectors
, safepos
);
5414 /* Having calculated the 'writepos' possibly use it
5415 * to set 'stripe_addr' which is where we will write to.
5417 if (mddev
->reshape_backwards
) {
5418 BUG_ON(conf
->reshape_progress
== 0);
5419 stripe_addr
= writepos
;
5420 BUG_ON((mddev
->dev_sectors
&
5421 ~((sector_t
)reshape_sectors
- 1))
5422 - reshape_sectors
- stripe_addr
5425 BUG_ON(writepos
!= sector_nr
+ reshape_sectors
);
5426 stripe_addr
= sector_nr
;
5429 /* 'writepos' is the most advanced device address we might write.
5430 * 'readpos' is the least advanced device address we might read.
5431 * 'safepos' is the least address recorded in the metadata as having
5433 * If there is a min_offset_diff, these are adjusted either by
5434 * increasing the safepos/readpos if diff is negative, or
5435 * increasing writepos if diff is positive.
5436 * If 'readpos' is then behind 'writepos', there is no way that we can
5437 * ensure safety in the face of a crash - that must be done by userspace
5438 * making a backup of the data. So in that case there is no particular
5439 * rush to update metadata.
5440 * Otherwise if 'safepos' is behind 'writepos', then we really need to
5441 * update the metadata to advance 'safepos' to match 'readpos' so that
5442 * we can be safe in the event of a crash.
5443 * So we insist on updating metadata if safepos is behind writepos and
5444 * readpos is beyond writepos.
5445 * In any case, update the metadata every 10 seconds.
5446 * Maybe that number should be configurable, but I'm not sure it is
5447 * worth it.... maybe it could be a multiple of safemode_delay???
5449 if (conf
->min_offset_diff
< 0) {
5450 safepos
+= -conf
->min_offset_diff
;
5451 readpos
+= -conf
->min_offset_diff
;
5453 writepos
+= conf
->min_offset_diff
;
5455 if ((mddev
->reshape_backwards
5456 ? (safepos
> writepos
&& readpos
< writepos
)
5457 : (safepos
< writepos
&& readpos
> writepos
)) ||
5458 time_after(jiffies
, conf
->reshape_checkpoint
+ 10*HZ
)) {
5459 /* Cannot proceed until we've updated the superblock... */
5460 wait_event(conf
->wait_for_overlap
,
5461 atomic_read(&conf
->reshape_stripes
)==0
5462 || test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
));
5463 if (atomic_read(&conf
->reshape_stripes
) != 0)
5465 mddev
->reshape_position
= conf
->reshape_progress
;
5466 mddev
->curr_resync_completed
= sector_nr
;
5467 conf
->reshape_checkpoint
= jiffies
;
5468 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
5469 md_wakeup_thread(mddev
->thread
);
5470 wait_event(mddev
->sb_wait
, mddev
->flags
== 0 ||
5471 test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
));
5472 if (test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
))
5474 spin_lock_irq(&conf
->device_lock
);
5475 conf
->reshape_safe
= mddev
->reshape_position
;
5476 spin_unlock_irq(&conf
->device_lock
);
5477 wake_up(&conf
->wait_for_overlap
);
5478 sysfs_notify(&mddev
->kobj
, NULL
, "sync_completed");
5481 INIT_LIST_HEAD(&stripes
);
5482 for (i
= 0; i
< reshape_sectors
; i
+= STRIPE_SECTORS
) {
5484 int skipped_disk
= 0;
5485 sh
= raid5_get_active_stripe(conf
, stripe_addr
+i
, 0, 0, 1);
5486 set_bit(STRIPE_EXPANDING
, &sh
->state
);
5487 atomic_inc(&conf
->reshape_stripes
);
5488 /* If any of this stripe is beyond the end of the old
5489 * array, then we need to zero those blocks
5491 for (j
=sh
->disks
; j
--;) {
5493 if (j
== sh
->pd_idx
)
5495 if (conf
->level
== 6 &&
5498 s
= raid5_compute_blocknr(sh
, j
, 0);
5499 if (s
< raid5_size(mddev
, 0, 0)) {
5503 memset(page_address(sh
->dev
[j
].page
), 0, STRIPE_SIZE
);
5504 set_bit(R5_Expanded
, &sh
->dev
[j
].flags
);
5505 set_bit(R5_UPTODATE
, &sh
->dev
[j
].flags
);
5507 if (!skipped_disk
) {
5508 set_bit(STRIPE_EXPAND_READY
, &sh
->state
);
5509 set_bit(STRIPE_HANDLE
, &sh
->state
);
5511 list_add(&sh
->lru
, &stripes
);
5513 spin_lock_irq(&conf
->device_lock
);
5514 if (mddev
->reshape_backwards
)
5515 conf
->reshape_progress
-= reshape_sectors
* new_data_disks
;
5517 conf
->reshape_progress
+= reshape_sectors
* new_data_disks
;
5518 spin_unlock_irq(&conf
->device_lock
);
5519 /* Ok, those stripe are ready. We can start scheduling
5520 * reads on the source stripes.
5521 * The source stripes are determined by mapping the first and last
5522 * block on the destination stripes.
5525 raid5_compute_sector(conf
, stripe_addr
*(new_data_disks
),
5528 raid5_compute_sector(conf
, ((stripe_addr
+reshape_sectors
)
5529 * new_data_disks
- 1),
5531 if (last_sector
>= mddev
->dev_sectors
)
5532 last_sector
= mddev
->dev_sectors
- 1;
5533 while (first_sector
<= last_sector
) {
5534 sh
= raid5_get_active_stripe(conf
, first_sector
, 1, 0, 1);
5535 set_bit(STRIPE_EXPAND_SOURCE
, &sh
->state
);
5536 set_bit(STRIPE_HANDLE
, &sh
->state
);
5537 raid5_release_stripe(sh
);
5538 first_sector
+= STRIPE_SECTORS
;
5540 /* Now that the sources are clearly marked, we can release
5541 * the destination stripes
5543 while (!list_empty(&stripes
)) {
5544 sh
= list_entry(stripes
.next
, struct stripe_head
, lru
);
5545 list_del_init(&sh
->lru
);
5546 raid5_release_stripe(sh
);
5548 /* If this takes us to the resync_max point where we have to pause,
5549 * then we need to write out the superblock.
5551 sector_nr
+= reshape_sectors
;
5552 retn
= reshape_sectors
;
5554 if (mddev
->curr_resync_completed
> mddev
->resync_max
||
5555 (sector_nr
- mddev
->curr_resync_completed
) * 2
5556 >= mddev
->resync_max
- mddev
->curr_resync_completed
) {
5557 /* Cannot proceed until we've updated the superblock... */
5558 wait_event(conf
->wait_for_overlap
,
5559 atomic_read(&conf
->reshape_stripes
) == 0
5560 || test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
));
5561 if (atomic_read(&conf
->reshape_stripes
) != 0)
5563 mddev
->reshape_position
= conf
->reshape_progress
;
5564 mddev
->curr_resync_completed
= sector_nr
;
5565 conf
->reshape_checkpoint
= jiffies
;
5566 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
5567 md_wakeup_thread(mddev
->thread
);
5568 wait_event(mddev
->sb_wait
,
5569 !test_bit(MD_CHANGE_DEVS
, &mddev
->flags
)
5570 || test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
));
5571 if (test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
))
5573 spin_lock_irq(&conf
->device_lock
);
5574 conf
->reshape_safe
= mddev
->reshape_position
;
5575 spin_unlock_irq(&conf
->device_lock
);
5576 wake_up(&conf
->wait_for_overlap
);
5577 sysfs_notify(&mddev
->kobj
, NULL
, "sync_completed");
5583 static inline sector_t
sync_request(struct mddev
*mddev
, sector_t sector_nr
, int *skipped
)
5585 struct r5conf
*conf
= mddev
->private;
5586 struct stripe_head
*sh
;
5587 sector_t max_sector
= mddev
->dev_sectors
;
5588 sector_t sync_blocks
;
5589 int still_degraded
= 0;
5592 if (sector_nr
>= max_sector
) {
5593 /* just being told to finish up .. nothing much to do */
5595 if (test_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
)) {
5600 if (mddev
->curr_resync
< max_sector
) /* aborted */
5601 bitmap_end_sync(mddev
->bitmap
, mddev
->curr_resync
,
5603 else /* completed sync */
5605 bitmap_close_sync(mddev
->bitmap
);
5610 /* Allow raid5_quiesce to complete */
5611 wait_event(conf
->wait_for_overlap
, conf
->quiesce
!= 2);
5613 if (test_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
))
5614 return reshape_request(mddev
, sector_nr
, skipped
);
5616 /* No need to check resync_max as we never do more than one
5617 * stripe, and as resync_max will always be on a chunk boundary,
5618 * if the check in md_do_sync didn't fire, there is no chance
5619 * of overstepping resync_max here
5622 /* if there is too many failed drives and we are trying
5623 * to resync, then assert that we are finished, because there is
5624 * nothing we can do.
5626 if (mddev
->degraded
>= conf
->max_degraded
&&
5627 test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
)) {
5628 sector_t rv
= mddev
->dev_sectors
- sector_nr
;
5632 if (!test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
) &&
5634 !bitmap_start_sync(mddev
->bitmap
, sector_nr
, &sync_blocks
, 1) &&
5635 sync_blocks
>= STRIPE_SECTORS
) {
5636 /* we can skip this block, and probably more */
5637 sync_blocks
/= STRIPE_SECTORS
;
5639 return sync_blocks
* STRIPE_SECTORS
; /* keep things rounded to whole stripes */
5642 bitmap_cond_end_sync(mddev
->bitmap
, sector_nr
, false);
5644 sh
= raid5_get_active_stripe(conf
, sector_nr
, 0, 1, 0);
5646 sh
= raid5_get_active_stripe(conf
, sector_nr
, 0, 0, 0);
5647 /* make sure we don't swamp the stripe cache if someone else
5648 * is trying to get access
5650 schedule_timeout_uninterruptible(1);
5652 /* Need to check if array will still be degraded after recovery/resync
5653 * Note in case of > 1 drive failures it's possible we're rebuilding
5654 * one drive while leaving another faulty drive in array.
5657 for (i
= 0; i
< conf
->raid_disks
; i
++) {
5658 struct md_rdev
*rdev
= ACCESS_ONCE(conf
->disks
[i
].rdev
);
5660 if (rdev
== NULL
|| test_bit(Faulty
, &rdev
->flags
))
5665 bitmap_start_sync(mddev
->bitmap
, sector_nr
, &sync_blocks
, still_degraded
);
5667 set_bit(STRIPE_SYNC_REQUESTED
, &sh
->state
);
5668 set_bit(STRIPE_HANDLE
, &sh
->state
);
5670 raid5_release_stripe(sh
);
5672 return STRIPE_SECTORS
;
5675 static int retry_aligned_read(struct r5conf
*conf
, struct bio
*raid_bio
)
5677 /* We may not be able to submit a whole bio at once as there
5678 * may not be enough stripe_heads available.
5679 * We cannot pre-allocate enough stripe_heads as we may need
5680 * more than exist in the cache (if we allow ever large chunks).
5681 * So we do one stripe head at a time and record in
5682 * ->bi_hw_segments how many have been done.
5684 * We *know* that this entire raid_bio is in one chunk, so
5685 * it will be only one 'dd_idx' and only need one call to raid5_compute_sector.
5687 struct stripe_head
*sh
;
5689 sector_t sector
, logical_sector
, last_sector
;
5694 logical_sector
= raid_bio
->bi_iter
.bi_sector
&
5695 ~((sector_t
)STRIPE_SECTORS
-1);
5696 sector
= raid5_compute_sector(conf
, logical_sector
,
5698 last_sector
= bio_end_sector(raid_bio
);
5700 for (; logical_sector
< last_sector
;
5701 logical_sector
+= STRIPE_SECTORS
,
5702 sector
+= STRIPE_SECTORS
,
5705 if (scnt
< raid5_bi_processed_stripes(raid_bio
))
5706 /* already done this stripe */
5709 sh
= raid5_get_active_stripe(conf
, sector
, 0, 1, 1);
5712 /* failed to get a stripe - must wait */
5713 raid5_set_bi_processed_stripes(raid_bio
, scnt
);
5714 conf
->retry_read_aligned
= raid_bio
;
5718 if (!add_stripe_bio(sh
, raid_bio
, dd_idx
, 0, 0)) {
5719 raid5_release_stripe(sh
);
5720 raid5_set_bi_processed_stripes(raid_bio
, scnt
);
5721 conf
->retry_read_aligned
= raid_bio
;
5725 set_bit(R5_ReadNoMerge
, &sh
->dev
[dd_idx
].flags
);
5727 raid5_release_stripe(sh
);
5730 remaining
= raid5_dec_bi_active_stripes(raid_bio
);
5731 if (remaining
== 0) {
5732 trace_block_bio_complete(bdev_get_queue(raid_bio
->bi_bdev
),
5734 bio_endio(raid_bio
);
5736 if (atomic_dec_and_test(&conf
->active_aligned_reads
))
5737 wake_up(&conf
->wait_for_quiescent
);
5741 static int handle_active_stripes(struct r5conf
*conf
, int group
,
5742 struct r5worker
*worker
,
5743 struct list_head
*temp_inactive_list
)
5745 struct stripe_head
*batch
[MAX_STRIPE_BATCH
], *sh
;
5746 int i
, batch_size
= 0, hash
;
5747 bool release_inactive
= false;
5749 while (batch_size
< MAX_STRIPE_BATCH
&&
5750 (sh
= __get_priority_stripe(conf
, group
)) != NULL
)
5751 batch
[batch_size
++] = sh
;
5753 if (batch_size
== 0) {
5754 for (i
= 0; i
< NR_STRIPE_HASH_LOCKS
; i
++)
5755 if (!list_empty(temp_inactive_list
+ i
))
5757 if (i
== NR_STRIPE_HASH_LOCKS
) {
5758 spin_unlock_irq(&conf
->device_lock
);
5759 r5l_flush_stripe_to_raid(conf
->log
);
5760 spin_lock_irq(&conf
->device_lock
);
5763 release_inactive
= true;
5765 spin_unlock_irq(&conf
->device_lock
);
5767 release_inactive_stripe_list(conf
, temp_inactive_list
,
5768 NR_STRIPE_HASH_LOCKS
);
5770 r5l_flush_stripe_to_raid(conf
->log
);
5771 if (release_inactive
) {
5772 spin_lock_irq(&conf
->device_lock
);
5776 for (i
= 0; i
< batch_size
; i
++)
5777 handle_stripe(batch
[i
]);
5778 r5l_write_stripe_run(conf
->log
);
5782 spin_lock_irq(&conf
->device_lock
);
5783 for (i
= 0; i
< batch_size
; i
++) {
5784 hash
= batch
[i
]->hash_lock_index
;
5785 __release_stripe(conf
, batch
[i
], &temp_inactive_list
[hash
]);
5790 static void raid5_do_work(struct work_struct
*work
)
5792 struct r5worker
*worker
= container_of(work
, struct r5worker
, work
);
5793 struct r5worker_group
*group
= worker
->group
;
5794 struct r5conf
*conf
= group
->conf
;
5795 int group_id
= group
- conf
->worker_groups
;
5797 struct blk_plug plug
;
5799 pr_debug("+++ raid5worker active\n");
5801 blk_start_plug(&plug
);
5803 spin_lock_irq(&conf
->device_lock
);
5805 int batch_size
, released
;
5807 released
= release_stripe_list(conf
, worker
->temp_inactive_list
);
5809 batch_size
= handle_active_stripes(conf
, group_id
, worker
,
5810 worker
->temp_inactive_list
);
5811 worker
->working
= false;
5812 if (!batch_size
&& !released
)
5814 handled
+= batch_size
;
5816 pr_debug("%d stripes handled\n", handled
);
5818 spin_unlock_irq(&conf
->device_lock
);
5819 blk_finish_plug(&plug
);
5821 pr_debug("--- raid5worker inactive\n");
5825 * This is our raid5 kernel thread.
5827 * We scan the hash table for stripes which can be handled now.
5828 * During the scan, completed stripes are saved for us by the interrupt
5829 * handler, so that they will not have to wait for our next wakeup.
5831 static void raid5d(struct md_thread
*thread
)
5833 struct mddev
*mddev
= thread
->mddev
;
5834 struct r5conf
*conf
= mddev
->private;
5836 struct blk_plug plug
;
5838 pr_debug("+++ raid5d active\n");
5840 md_check_recovery(mddev
);
5842 if (!bio_list_empty(&conf
->return_bi
) &&
5843 !test_bit(MD_CHANGE_PENDING
, &mddev
->flags
)) {
5844 struct bio_list tmp
= BIO_EMPTY_LIST
;
5845 spin_lock_irq(&conf
->device_lock
);
5846 if (!test_bit(MD_CHANGE_PENDING
, &mddev
->flags
)) {
5847 bio_list_merge(&tmp
, &conf
->return_bi
);
5848 bio_list_init(&conf
->return_bi
);
5850 spin_unlock_irq(&conf
->device_lock
);
5854 blk_start_plug(&plug
);
5856 spin_lock_irq(&conf
->device_lock
);
5859 int batch_size
, released
;
5861 released
= release_stripe_list(conf
, conf
->temp_inactive_list
);
5863 clear_bit(R5_DID_ALLOC
, &conf
->cache_state
);
5866 !list_empty(&conf
->bitmap_list
)) {
5867 /* Now is a good time to flush some bitmap updates */
5869 spin_unlock_irq(&conf
->device_lock
);
5870 bitmap_unplug(mddev
->bitmap
);
5871 spin_lock_irq(&conf
->device_lock
);
5872 conf
->seq_write
= conf
->seq_flush
;
5873 activate_bit_delay(conf
, conf
->temp_inactive_list
);
5875 raid5_activate_delayed(conf
);
5877 while ((bio
= remove_bio_from_retry(conf
))) {
5879 spin_unlock_irq(&conf
->device_lock
);
5880 ok
= retry_aligned_read(conf
, bio
);
5881 spin_lock_irq(&conf
->device_lock
);
5887 batch_size
= handle_active_stripes(conf
, ANY_GROUP
, NULL
,
5888 conf
->temp_inactive_list
);
5889 if (!batch_size
&& !released
)
5891 handled
+= batch_size
;
5893 if (mddev
->flags
& ~(1<<MD_CHANGE_PENDING
)) {
5894 spin_unlock_irq(&conf
->device_lock
);
5895 md_check_recovery(mddev
);
5896 spin_lock_irq(&conf
->device_lock
);
5899 pr_debug("%d stripes handled\n", handled
);
5901 spin_unlock_irq(&conf
->device_lock
);
5902 if (test_and_clear_bit(R5_ALLOC_MORE
, &conf
->cache_state
) &&
5903 mutex_trylock(&conf
->cache_size_mutex
)) {
5904 grow_one_stripe(conf
, __GFP_NOWARN
);
5905 /* Set flag even if allocation failed. This helps
5906 * slow down allocation requests when mem is short
5908 set_bit(R5_DID_ALLOC
, &conf
->cache_state
);
5909 mutex_unlock(&conf
->cache_size_mutex
);
5912 r5l_flush_stripe_to_raid(conf
->log
);
5914 async_tx_issue_pending_all();
5915 blk_finish_plug(&plug
);
5917 pr_debug("--- raid5d inactive\n");
5921 raid5_show_stripe_cache_size(struct mddev
*mddev
, char *page
)
5923 struct r5conf
*conf
;
5925 spin_lock(&mddev
->lock
);
5926 conf
= mddev
->private;
5928 ret
= sprintf(page
, "%d\n", conf
->min_nr_stripes
);
5929 spin_unlock(&mddev
->lock
);
5934 raid5_set_cache_size(struct mddev
*mddev
, int size
)
5936 struct r5conf
*conf
= mddev
->private;
5939 if (size
<= 16 || size
> 32768)
5942 conf
->min_nr_stripes
= size
;
5943 mutex_lock(&conf
->cache_size_mutex
);
5944 while (size
< conf
->max_nr_stripes
&&
5945 drop_one_stripe(conf
))
5947 mutex_unlock(&conf
->cache_size_mutex
);
5950 err
= md_allow_write(mddev
);
5954 mutex_lock(&conf
->cache_size_mutex
);
5955 while (size
> conf
->max_nr_stripes
)
5956 if (!grow_one_stripe(conf
, GFP_KERNEL
))
5958 mutex_unlock(&conf
->cache_size_mutex
);
5962 EXPORT_SYMBOL(raid5_set_cache_size
);
5965 raid5_store_stripe_cache_size(struct mddev
*mddev
, const char *page
, size_t len
)
5967 struct r5conf
*conf
;
5971 if (len
>= PAGE_SIZE
)
5973 if (kstrtoul(page
, 10, &new))
5975 err
= mddev_lock(mddev
);
5978 conf
= mddev
->private;
5982 err
= raid5_set_cache_size(mddev
, new);
5983 mddev_unlock(mddev
);
5988 static struct md_sysfs_entry
5989 raid5_stripecache_size
= __ATTR(stripe_cache_size
, S_IRUGO
| S_IWUSR
,
5990 raid5_show_stripe_cache_size
,
5991 raid5_store_stripe_cache_size
);
5994 raid5_show_rmw_level(struct mddev
*mddev
, char *page
)
5996 struct r5conf
*conf
= mddev
->private;
5998 return sprintf(page
, "%d\n", conf
->rmw_level
);
6004 raid5_store_rmw_level(struct mddev
*mddev
, const char *page
, size_t len
)
6006 struct r5conf
*conf
= mddev
->private;
6012 if (len
>= PAGE_SIZE
)
6015 if (kstrtoul(page
, 10, &new))
6018 if (new != PARITY_DISABLE_RMW
&& !raid6_call
.xor_syndrome
)
6021 if (new != PARITY_DISABLE_RMW
&&
6022 new != PARITY_ENABLE_RMW
&&
6023 new != PARITY_PREFER_RMW
)
6026 conf
->rmw_level
= new;
6030 static struct md_sysfs_entry
6031 raid5_rmw_level
= __ATTR(rmw_level
, S_IRUGO
| S_IWUSR
,
6032 raid5_show_rmw_level
,
6033 raid5_store_rmw_level
);
6037 raid5_show_preread_threshold(struct mddev
*mddev
, char *page
)
6039 struct r5conf
*conf
;
6041 spin_lock(&mddev
->lock
);
6042 conf
= mddev
->private;
6044 ret
= sprintf(page
, "%d\n", conf
->bypass_threshold
);
6045 spin_unlock(&mddev
->lock
);
6050 raid5_store_preread_threshold(struct mddev
*mddev
, const char *page
, size_t len
)
6052 struct r5conf
*conf
;
6056 if (len
>= PAGE_SIZE
)
6058 if (kstrtoul(page
, 10, &new))
6061 err
= mddev_lock(mddev
);
6064 conf
= mddev
->private;
6067 else if (new > conf
->min_nr_stripes
)
6070 conf
->bypass_threshold
= new;
6071 mddev_unlock(mddev
);
6075 static struct md_sysfs_entry
6076 raid5_preread_bypass_threshold
= __ATTR(preread_bypass_threshold
,
6078 raid5_show_preread_threshold
,
6079 raid5_store_preread_threshold
);
6082 raid5_show_skip_copy(struct mddev
*mddev
, char *page
)
6084 struct r5conf
*conf
;
6086 spin_lock(&mddev
->lock
);
6087 conf
= mddev
->private;
6089 ret
= sprintf(page
, "%d\n", conf
->skip_copy
);
6090 spin_unlock(&mddev
->lock
);
6095 raid5_store_skip_copy(struct mddev
*mddev
, const char *page
, size_t len
)
6097 struct r5conf
*conf
;
6101 if (len
>= PAGE_SIZE
)
6103 if (kstrtoul(page
, 10, &new))
6107 err
= mddev_lock(mddev
);
6110 conf
= mddev
->private;
6113 else if (new != conf
->skip_copy
) {
6114 mddev_suspend(mddev
);
6115 conf
->skip_copy
= new;
6117 mddev
->queue
->backing_dev_info
.capabilities
|=
6118 BDI_CAP_STABLE_WRITES
;
6120 mddev
->queue
->backing_dev_info
.capabilities
&=
6121 ~BDI_CAP_STABLE_WRITES
;
6122 mddev_resume(mddev
);
6124 mddev_unlock(mddev
);
6128 static struct md_sysfs_entry
6129 raid5_skip_copy
= __ATTR(skip_copy
, S_IRUGO
| S_IWUSR
,
6130 raid5_show_skip_copy
,
6131 raid5_store_skip_copy
);
6134 stripe_cache_active_show(struct mddev
*mddev
, char *page
)
6136 struct r5conf
*conf
= mddev
->private;
6138 return sprintf(page
, "%d\n", atomic_read(&conf
->active_stripes
));
6143 static struct md_sysfs_entry
6144 raid5_stripecache_active
= __ATTR_RO(stripe_cache_active
);
6147 raid5_show_group_thread_cnt(struct mddev
*mddev
, char *page
)
6149 struct r5conf
*conf
;
6151 spin_lock(&mddev
->lock
);
6152 conf
= mddev
->private;
6154 ret
= sprintf(page
, "%d\n", conf
->worker_cnt_per_group
);
6155 spin_unlock(&mddev
->lock
);
6159 static int alloc_thread_groups(struct r5conf
*conf
, int cnt
,
6161 int *worker_cnt_per_group
,
6162 struct r5worker_group
**worker_groups
);
6164 raid5_store_group_thread_cnt(struct mddev
*mddev
, const char *page
, size_t len
)
6166 struct r5conf
*conf
;
6169 struct r5worker_group
*new_groups
, *old_groups
;
6170 int group_cnt
, worker_cnt_per_group
;
6172 if (len
>= PAGE_SIZE
)
6174 if (kstrtoul(page
, 10, &new))
6177 err
= mddev_lock(mddev
);
6180 conf
= mddev
->private;
6183 else if (new != conf
->worker_cnt_per_group
) {
6184 mddev_suspend(mddev
);
6186 old_groups
= conf
->worker_groups
;
6188 flush_workqueue(raid5_wq
);
6190 err
= alloc_thread_groups(conf
, new,
6191 &group_cnt
, &worker_cnt_per_group
,
6194 spin_lock_irq(&conf
->device_lock
);
6195 conf
->group_cnt
= group_cnt
;
6196 conf
->worker_cnt_per_group
= worker_cnt_per_group
;
6197 conf
->worker_groups
= new_groups
;
6198 spin_unlock_irq(&conf
->device_lock
);
6201 kfree(old_groups
[0].workers
);
6204 mddev_resume(mddev
);
6206 mddev_unlock(mddev
);
6211 static struct md_sysfs_entry
6212 raid5_group_thread_cnt
= __ATTR(group_thread_cnt
, S_IRUGO
| S_IWUSR
,
6213 raid5_show_group_thread_cnt
,
6214 raid5_store_group_thread_cnt
);
6216 static struct attribute
*raid5_attrs
[] = {
6217 &raid5_stripecache_size
.attr
,
6218 &raid5_stripecache_active
.attr
,
6219 &raid5_preread_bypass_threshold
.attr
,
6220 &raid5_group_thread_cnt
.attr
,
6221 &raid5_skip_copy
.attr
,
6222 &raid5_rmw_level
.attr
,
6225 static struct attribute_group raid5_attrs_group
= {
6227 .attrs
= raid5_attrs
,
6230 static int alloc_thread_groups(struct r5conf
*conf
, int cnt
,
6232 int *worker_cnt_per_group
,
6233 struct r5worker_group
**worker_groups
)
6237 struct r5worker
*workers
;
6239 *worker_cnt_per_group
= cnt
;
6242 *worker_groups
= NULL
;
6245 *group_cnt
= num_possible_nodes();
6246 size
= sizeof(struct r5worker
) * cnt
;
6247 workers
= kzalloc(size
* *group_cnt
, GFP_NOIO
);
6248 *worker_groups
= kzalloc(sizeof(struct r5worker_group
) *
6249 *group_cnt
, GFP_NOIO
);
6250 if (!*worker_groups
|| !workers
) {
6252 kfree(*worker_groups
);
6256 for (i
= 0; i
< *group_cnt
; i
++) {
6257 struct r5worker_group
*group
;
6259 group
= &(*worker_groups
)[i
];
6260 INIT_LIST_HEAD(&group
->handle_list
);
6262 group
->workers
= workers
+ i
* cnt
;
6264 for (j
= 0; j
< cnt
; j
++) {
6265 struct r5worker
*worker
= group
->workers
+ j
;
6266 worker
->group
= group
;
6267 INIT_WORK(&worker
->work
, raid5_do_work
);
6269 for (k
= 0; k
< NR_STRIPE_HASH_LOCKS
; k
++)
6270 INIT_LIST_HEAD(worker
->temp_inactive_list
+ k
);
6277 static void free_thread_groups(struct r5conf
*conf
)
6279 if (conf
->worker_groups
)
6280 kfree(conf
->worker_groups
[0].workers
);
6281 kfree(conf
->worker_groups
);
6282 conf
->worker_groups
= NULL
;
6286 raid5_size(struct mddev
*mddev
, sector_t sectors
, int raid_disks
)
6288 struct r5conf
*conf
= mddev
->private;
6291 sectors
= mddev
->dev_sectors
;
6293 /* size is defined by the smallest of previous and new size */
6294 raid_disks
= min(conf
->raid_disks
, conf
->previous_raid_disks
);
6296 sectors
&= ~((sector_t
)conf
->chunk_sectors
- 1);
6297 sectors
&= ~((sector_t
)conf
->prev_chunk_sectors
- 1);
6298 return sectors
* (raid_disks
- conf
->max_degraded
);
6301 static void free_scratch_buffer(struct r5conf
*conf
, struct raid5_percpu
*percpu
)
6303 safe_put_page(percpu
->spare_page
);
6304 if (percpu
->scribble
)
6305 flex_array_free(percpu
->scribble
);
6306 percpu
->spare_page
= NULL
;
6307 percpu
->scribble
= NULL
;
6310 static int alloc_scratch_buffer(struct r5conf
*conf
, struct raid5_percpu
*percpu
)
6312 if (conf
->level
== 6 && !percpu
->spare_page
)
6313 percpu
->spare_page
= alloc_page(GFP_KERNEL
);
6314 if (!percpu
->scribble
)
6315 percpu
->scribble
= scribble_alloc(max(conf
->raid_disks
,
6316 conf
->previous_raid_disks
),
6317 max(conf
->chunk_sectors
,
6318 conf
->prev_chunk_sectors
)
6322 if (!percpu
->scribble
|| (conf
->level
== 6 && !percpu
->spare_page
)) {
6323 free_scratch_buffer(conf
, percpu
);
6330 static void raid5_free_percpu(struct r5conf
*conf
)
6337 #ifdef CONFIG_HOTPLUG_CPU
6338 unregister_cpu_notifier(&conf
->cpu_notify
);
6342 for_each_possible_cpu(cpu
)
6343 free_scratch_buffer(conf
, per_cpu_ptr(conf
->percpu
, cpu
));
6346 free_percpu(conf
->percpu
);
6349 static void free_conf(struct r5conf
*conf
)
6352 r5l_exit_log(conf
->log
);
6353 if (conf
->shrinker
.seeks
)
6354 unregister_shrinker(&conf
->shrinker
);
6356 free_thread_groups(conf
);
6357 shrink_stripes(conf
);
6358 raid5_free_percpu(conf
);
6360 kfree(conf
->stripe_hashtbl
);
6364 #ifdef CONFIG_HOTPLUG_CPU
6365 static int raid456_cpu_notify(struct notifier_block
*nfb
, unsigned long action
,
6368 struct r5conf
*conf
= container_of(nfb
, struct r5conf
, cpu_notify
);
6369 long cpu
= (long)hcpu
;
6370 struct raid5_percpu
*percpu
= per_cpu_ptr(conf
->percpu
, cpu
);
6373 case CPU_UP_PREPARE
:
6374 case CPU_UP_PREPARE_FROZEN
:
6375 if (alloc_scratch_buffer(conf
, percpu
)) {
6376 pr_err("%s: failed memory allocation for cpu%ld\n",
6378 return notifier_from_errno(-ENOMEM
);
6382 case CPU_DEAD_FROZEN
:
6383 free_scratch_buffer(conf
, per_cpu_ptr(conf
->percpu
, cpu
));
6392 static int raid5_alloc_percpu(struct r5conf
*conf
)
6397 conf
->percpu
= alloc_percpu(struct raid5_percpu
);
6401 #ifdef CONFIG_HOTPLUG_CPU
6402 conf
->cpu_notify
.notifier_call
= raid456_cpu_notify
;
6403 conf
->cpu_notify
.priority
= 0;
6404 err
= register_cpu_notifier(&conf
->cpu_notify
);
6410 for_each_present_cpu(cpu
) {
6411 err
= alloc_scratch_buffer(conf
, per_cpu_ptr(conf
->percpu
, cpu
));
6413 pr_err("%s: failed memory allocation for cpu%ld\n",
6421 conf
->scribble_disks
= max(conf
->raid_disks
,
6422 conf
->previous_raid_disks
);
6423 conf
->scribble_sectors
= max(conf
->chunk_sectors
,
6424 conf
->prev_chunk_sectors
);
6429 static unsigned long raid5_cache_scan(struct shrinker
*shrink
,
6430 struct shrink_control
*sc
)
6432 struct r5conf
*conf
= container_of(shrink
, struct r5conf
, shrinker
);
6433 unsigned long ret
= SHRINK_STOP
;
6435 if (mutex_trylock(&conf
->cache_size_mutex
)) {
6437 while (ret
< sc
->nr_to_scan
&&
6438 conf
->max_nr_stripes
> conf
->min_nr_stripes
) {
6439 if (drop_one_stripe(conf
) == 0) {
6445 mutex_unlock(&conf
->cache_size_mutex
);
6450 static unsigned long raid5_cache_count(struct shrinker
*shrink
,
6451 struct shrink_control
*sc
)
6453 struct r5conf
*conf
= container_of(shrink
, struct r5conf
, shrinker
);
6455 if (conf
->max_nr_stripes
< conf
->min_nr_stripes
)
6456 /* unlikely, but not impossible */
6458 return conf
->max_nr_stripes
- conf
->min_nr_stripes
;
6461 static struct r5conf
*setup_conf(struct mddev
*mddev
)
6463 struct r5conf
*conf
;
6464 int raid_disk
, memory
, max_disks
;
6465 struct md_rdev
*rdev
;
6466 struct disk_info
*disk
;
6469 int group_cnt
, worker_cnt_per_group
;
6470 struct r5worker_group
*new_group
;
6472 if (mddev
->new_level
!= 5
6473 && mddev
->new_level
!= 4
6474 && mddev
->new_level
!= 6) {
6475 printk(KERN_ERR
"md/raid:%s: raid level not set to 4/5/6 (%d)\n",
6476 mdname(mddev
), mddev
->new_level
);
6477 return ERR_PTR(-EIO
);
6479 if ((mddev
->new_level
== 5
6480 && !algorithm_valid_raid5(mddev
->new_layout
)) ||
6481 (mddev
->new_level
== 6
6482 && !algorithm_valid_raid6(mddev
->new_layout
))) {
6483 printk(KERN_ERR
"md/raid:%s: layout %d not supported\n",
6484 mdname(mddev
), mddev
->new_layout
);
6485 return ERR_PTR(-EIO
);
6487 if (mddev
->new_level
== 6 && mddev
->raid_disks
< 4) {
6488 printk(KERN_ERR
"md/raid:%s: not enough configured devices (%d, minimum 4)\n",
6489 mdname(mddev
), mddev
->raid_disks
);
6490 return ERR_PTR(-EINVAL
);
6493 if (!mddev
->new_chunk_sectors
||
6494 (mddev
->new_chunk_sectors
<< 9) % PAGE_SIZE
||
6495 !is_power_of_2(mddev
->new_chunk_sectors
)) {
6496 printk(KERN_ERR
"md/raid:%s: invalid chunk size %d\n",
6497 mdname(mddev
), mddev
->new_chunk_sectors
<< 9);
6498 return ERR_PTR(-EINVAL
);
6501 conf
= kzalloc(sizeof(struct r5conf
), GFP_KERNEL
);
6504 /* Don't enable multi-threading by default*/
6505 if (!alloc_thread_groups(conf
, 0, &group_cnt
, &worker_cnt_per_group
,
6507 conf
->group_cnt
= group_cnt
;
6508 conf
->worker_cnt_per_group
= worker_cnt_per_group
;
6509 conf
->worker_groups
= new_group
;
6512 spin_lock_init(&conf
->device_lock
);
6513 seqcount_init(&conf
->gen_lock
);
6514 mutex_init(&conf
->cache_size_mutex
);
6515 init_waitqueue_head(&conf
->wait_for_quiescent
);
6516 init_waitqueue_head(&conf
->wait_for_stripe
);
6517 init_waitqueue_head(&conf
->wait_for_overlap
);
6518 INIT_LIST_HEAD(&conf
->handle_list
);
6519 INIT_LIST_HEAD(&conf
->hold_list
);
6520 INIT_LIST_HEAD(&conf
->delayed_list
);
6521 INIT_LIST_HEAD(&conf
->bitmap_list
);
6522 bio_list_init(&conf
->return_bi
);
6523 init_llist_head(&conf
->released_stripes
);
6524 atomic_set(&conf
->active_stripes
, 0);
6525 atomic_set(&conf
->preread_active_stripes
, 0);
6526 atomic_set(&conf
->active_aligned_reads
, 0);
6527 conf
->bypass_threshold
= BYPASS_THRESHOLD
;
6528 conf
->recovery_disabled
= mddev
->recovery_disabled
- 1;
6530 conf
->raid_disks
= mddev
->raid_disks
;
6531 if (mddev
->reshape_position
== MaxSector
)
6532 conf
->previous_raid_disks
= mddev
->raid_disks
;
6534 conf
->previous_raid_disks
= mddev
->raid_disks
- mddev
->delta_disks
;
6535 max_disks
= max(conf
->raid_disks
, conf
->previous_raid_disks
);
6537 conf
->disks
= kzalloc(max_disks
* sizeof(struct disk_info
),
6542 conf
->mddev
= mddev
;
6544 if ((conf
->stripe_hashtbl
= kzalloc(PAGE_SIZE
, GFP_KERNEL
)) == NULL
)
6547 /* We init hash_locks[0] separately to that it can be used
6548 * as the reference lock in the spin_lock_nest_lock() call
6549 * in lock_all_device_hash_locks_irq in order to convince
6550 * lockdep that we know what we are doing.
6552 spin_lock_init(conf
->hash_locks
);
6553 for (i
= 1; i
< NR_STRIPE_HASH_LOCKS
; i
++)
6554 spin_lock_init(conf
->hash_locks
+ i
);
6556 for (i
= 0; i
< NR_STRIPE_HASH_LOCKS
; i
++)
6557 INIT_LIST_HEAD(conf
->inactive_list
+ i
);
6559 for (i
= 0; i
< NR_STRIPE_HASH_LOCKS
; i
++)
6560 INIT_LIST_HEAD(conf
->temp_inactive_list
+ i
);
6562 conf
->level
= mddev
->new_level
;
6563 conf
->chunk_sectors
= mddev
->new_chunk_sectors
;
6564 if (raid5_alloc_percpu(conf
) != 0)
6567 pr_debug("raid456: run(%s) called.\n", mdname(mddev
));
6569 rdev_for_each(rdev
, mddev
) {
6570 raid_disk
= rdev
->raid_disk
;
6571 if (raid_disk
>= max_disks
6572 || raid_disk
< 0 || test_bit(Journal
, &rdev
->flags
))
6574 disk
= conf
->disks
+ raid_disk
;
6576 if (test_bit(Replacement
, &rdev
->flags
)) {
6577 if (disk
->replacement
)
6579 disk
->replacement
= rdev
;
6586 if (test_bit(In_sync
, &rdev
->flags
)) {
6587 char b
[BDEVNAME_SIZE
];
6588 printk(KERN_INFO
"md/raid:%s: device %s operational as raid"
6590 mdname(mddev
), bdevname(rdev
->bdev
, b
), raid_disk
);
6591 } else if (rdev
->saved_raid_disk
!= raid_disk
)
6592 /* Cannot rely on bitmap to complete recovery */
6596 conf
->level
= mddev
->new_level
;
6597 if (conf
->level
== 6) {
6598 conf
->max_degraded
= 2;
6599 if (raid6_call
.xor_syndrome
)
6600 conf
->rmw_level
= PARITY_ENABLE_RMW
;
6602 conf
->rmw_level
= PARITY_DISABLE_RMW
;
6604 conf
->max_degraded
= 1;
6605 conf
->rmw_level
= PARITY_ENABLE_RMW
;
6607 conf
->algorithm
= mddev
->new_layout
;
6608 conf
->reshape_progress
= mddev
->reshape_position
;
6609 if (conf
->reshape_progress
!= MaxSector
) {
6610 conf
->prev_chunk_sectors
= mddev
->chunk_sectors
;
6611 conf
->prev_algo
= mddev
->layout
;
6613 conf
->prev_chunk_sectors
= conf
->chunk_sectors
;
6614 conf
->prev_algo
= conf
->algorithm
;
6617 conf
->min_nr_stripes
= NR_STRIPES
;
6618 memory
= conf
->min_nr_stripes
* (sizeof(struct stripe_head
) +
6619 max_disks
* ((sizeof(struct bio
) + PAGE_SIZE
))) / 1024;
6620 atomic_set(&conf
->empty_inactive_list_nr
, NR_STRIPE_HASH_LOCKS
);
6621 if (grow_stripes(conf
, conf
->min_nr_stripes
)) {
6623 "md/raid:%s: couldn't allocate %dkB for buffers\n",
6624 mdname(mddev
), memory
);
6627 printk(KERN_INFO
"md/raid:%s: allocated %dkB\n",
6628 mdname(mddev
), memory
);
6630 * Losing a stripe head costs more than the time to refill it,
6631 * it reduces the queue depth and so can hurt throughput.
6632 * So set it rather large, scaled by number of devices.
6634 conf
->shrinker
.seeks
= DEFAULT_SEEKS
* conf
->raid_disks
* 4;
6635 conf
->shrinker
.scan_objects
= raid5_cache_scan
;
6636 conf
->shrinker
.count_objects
= raid5_cache_count
;
6637 conf
->shrinker
.batch
= 128;
6638 conf
->shrinker
.flags
= 0;
6639 register_shrinker(&conf
->shrinker
);
6641 sprintf(pers_name
, "raid%d", mddev
->new_level
);
6642 conf
->thread
= md_register_thread(raid5d
, mddev
, pers_name
);
6643 if (!conf
->thread
) {
6645 "md/raid:%s: couldn't allocate thread.\n",
6655 return ERR_PTR(-EIO
);
6657 return ERR_PTR(-ENOMEM
);
6660 static int only_parity(int raid_disk
, int algo
, int raid_disks
, int max_degraded
)
6663 case ALGORITHM_PARITY_0
:
6664 if (raid_disk
< max_degraded
)
6667 case ALGORITHM_PARITY_N
:
6668 if (raid_disk
>= raid_disks
- max_degraded
)
6671 case ALGORITHM_PARITY_0_6
:
6672 if (raid_disk
== 0 ||
6673 raid_disk
== raid_disks
- 1)
6676 case ALGORITHM_LEFT_ASYMMETRIC_6
:
6677 case ALGORITHM_RIGHT_ASYMMETRIC_6
:
6678 case ALGORITHM_LEFT_SYMMETRIC_6
:
6679 case ALGORITHM_RIGHT_SYMMETRIC_6
:
6680 if (raid_disk
== raid_disks
- 1)
6686 static int run(struct mddev
*mddev
)
6688 struct r5conf
*conf
;
6689 int working_disks
= 0;
6690 int dirty_parity_disks
= 0;
6691 struct md_rdev
*rdev
;
6692 struct md_rdev
*journal_dev
= NULL
;
6693 sector_t reshape_offset
= 0;
6695 long long min_offset_diff
= 0;
6698 if (mddev
->recovery_cp
!= MaxSector
)
6699 printk(KERN_NOTICE
"md/raid:%s: not clean"
6700 " -- starting background reconstruction\n",
6703 rdev_for_each(rdev
, mddev
) {
6706 if (test_bit(Journal
, &rdev
->flags
)) {
6710 if (rdev
->raid_disk
< 0)
6712 diff
= (rdev
->new_data_offset
- rdev
->data_offset
);
6714 min_offset_diff
= diff
;
6716 } else if (mddev
->reshape_backwards
&&
6717 diff
< min_offset_diff
)
6718 min_offset_diff
= diff
;
6719 else if (!mddev
->reshape_backwards
&&
6720 diff
> min_offset_diff
)
6721 min_offset_diff
= diff
;
6724 if (mddev
->reshape_position
!= MaxSector
) {
6725 /* Check that we can continue the reshape.
6726 * Difficulties arise if the stripe we would write to
6727 * next is at or after the stripe we would read from next.
6728 * For a reshape that changes the number of devices, this
6729 * is only possible for a very short time, and mdadm makes
6730 * sure that time appears to have past before assembling
6731 * the array. So we fail if that time hasn't passed.
6732 * For a reshape that keeps the number of devices the same
6733 * mdadm must be monitoring the reshape can keeping the
6734 * critical areas read-only and backed up. It will start
6735 * the array in read-only mode, so we check for that.
6737 sector_t here_new
, here_old
;
6739 int max_degraded
= (mddev
->level
== 6 ? 2 : 1);
6744 printk(KERN_ERR
"md/raid:%s: don't support reshape with journal - aborting.\n",
6749 if (mddev
->new_level
!= mddev
->level
) {
6750 printk(KERN_ERR
"md/raid:%s: unsupported reshape "
6751 "required - aborting.\n",
6755 old_disks
= mddev
->raid_disks
- mddev
->delta_disks
;
6756 /* reshape_position must be on a new-stripe boundary, and one
6757 * further up in new geometry must map after here in old
6759 * If the chunk sizes are different, then as we perform reshape
6760 * in units of the largest of the two, reshape_position needs
6761 * be a multiple of the largest chunk size times new data disks.
6763 here_new
= mddev
->reshape_position
;
6764 chunk_sectors
= max(mddev
->chunk_sectors
, mddev
->new_chunk_sectors
);
6765 new_data_disks
= mddev
->raid_disks
- max_degraded
;
6766 if (sector_div(here_new
, chunk_sectors
* new_data_disks
)) {
6767 printk(KERN_ERR
"md/raid:%s: reshape_position not "
6768 "on a stripe boundary\n", mdname(mddev
));
6771 reshape_offset
= here_new
* chunk_sectors
;
6772 /* here_new is the stripe we will write to */
6773 here_old
= mddev
->reshape_position
;
6774 sector_div(here_old
, chunk_sectors
* (old_disks
-max_degraded
));
6775 /* here_old is the first stripe that we might need to read
6777 if (mddev
->delta_disks
== 0) {
6778 /* We cannot be sure it is safe to start an in-place
6779 * reshape. It is only safe if user-space is monitoring
6780 * and taking constant backups.
6781 * mdadm always starts a situation like this in
6782 * readonly mode so it can take control before
6783 * allowing any writes. So just check for that.
6785 if (abs(min_offset_diff
) >= mddev
->chunk_sectors
&&
6786 abs(min_offset_diff
) >= mddev
->new_chunk_sectors
)
6787 /* not really in-place - so OK */;
6788 else if (mddev
->ro
== 0) {
6789 printk(KERN_ERR
"md/raid:%s: in-place reshape "
6790 "must be started in read-only mode "
6795 } else if (mddev
->reshape_backwards
6796 ? (here_new
* chunk_sectors
+ min_offset_diff
<=
6797 here_old
* chunk_sectors
)
6798 : (here_new
* chunk_sectors
>=
6799 here_old
* chunk_sectors
+ (-min_offset_diff
))) {
6800 /* Reading from the same stripe as writing to - bad */
6801 printk(KERN_ERR
"md/raid:%s: reshape_position too early for "
6802 "auto-recovery - aborting.\n",
6806 printk(KERN_INFO
"md/raid:%s: reshape will continue\n",
6808 /* OK, we should be able to continue; */
6810 BUG_ON(mddev
->level
!= mddev
->new_level
);
6811 BUG_ON(mddev
->layout
!= mddev
->new_layout
);
6812 BUG_ON(mddev
->chunk_sectors
!= mddev
->new_chunk_sectors
);
6813 BUG_ON(mddev
->delta_disks
!= 0);
6816 if (mddev
->private == NULL
)
6817 conf
= setup_conf(mddev
);
6819 conf
= mddev
->private;
6822 return PTR_ERR(conf
);
6824 if (test_bit(MD_HAS_JOURNAL
, &mddev
->flags
) && !journal_dev
) {
6825 printk(KERN_ERR
"md/raid:%s: journal disk is missing, force array readonly\n",
6828 set_disk_ro(mddev
->gendisk
, 1);
6831 conf
->min_offset_diff
= min_offset_diff
;
6832 mddev
->thread
= conf
->thread
;
6833 conf
->thread
= NULL
;
6834 mddev
->private = conf
;
6836 for (i
= 0; i
< conf
->raid_disks
&& conf
->previous_raid_disks
;
6838 rdev
= conf
->disks
[i
].rdev
;
6839 if (!rdev
&& conf
->disks
[i
].replacement
) {
6840 /* The replacement is all we have yet */
6841 rdev
= conf
->disks
[i
].replacement
;
6842 conf
->disks
[i
].replacement
= NULL
;
6843 clear_bit(Replacement
, &rdev
->flags
);
6844 conf
->disks
[i
].rdev
= rdev
;
6848 if (conf
->disks
[i
].replacement
&&
6849 conf
->reshape_progress
!= MaxSector
) {
6850 /* replacements and reshape simply do not mix. */
6851 printk(KERN_ERR
"md: cannot handle concurrent "
6852 "replacement and reshape.\n");
6855 if (test_bit(In_sync
, &rdev
->flags
)) {
6859 /* This disc is not fully in-sync. However if it
6860 * just stored parity (beyond the recovery_offset),
6861 * when we don't need to be concerned about the
6862 * array being dirty.
6863 * When reshape goes 'backwards', we never have
6864 * partially completed devices, so we only need
6865 * to worry about reshape going forwards.
6867 /* Hack because v0.91 doesn't store recovery_offset properly. */
6868 if (mddev
->major_version
== 0 &&
6869 mddev
->minor_version
> 90)
6870 rdev
->recovery_offset
= reshape_offset
;
6872 if (rdev
->recovery_offset
< reshape_offset
) {
6873 /* We need to check old and new layout */
6874 if (!only_parity(rdev
->raid_disk
,
6877 conf
->max_degraded
))
6880 if (!only_parity(rdev
->raid_disk
,
6882 conf
->previous_raid_disks
,
6883 conf
->max_degraded
))
6885 dirty_parity_disks
++;
6889 * 0 for a fully functional array, 1 or 2 for a degraded array.
6891 mddev
->degraded
= calc_degraded(conf
);
6893 if (has_failed(conf
)) {
6894 printk(KERN_ERR
"md/raid:%s: not enough operational devices"
6895 " (%d/%d failed)\n",
6896 mdname(mddev
), mddev
->degraded
, conf
->raid_disks
);
6900 /* device size must be a multiple of chunk size */
6901 mddev
->dev_sectors
&= ~(mddev
->chunk_sectors
- 1);
6902 mddev
->resync_max_sectors
= mddev
->dev_sectors
;
6904 if (mddev
->degraded
> dirty_parity_disks
&&
6905 mddev
->recovery_cp
!= MaxSector
) {
6906 if (mddev
->ok_start_degraded
)
6908 "md/raid:%s: starting dirty degraded array"
6909 " - data corruption possible.\n",
6913 "md/raid:%s: cannot start dirty degraded array.\n",
6919 if (mddev
->degraded
== 0)
6920 printk(KERN_INFO
"md/raid:%s: raid level %d active with %d out of %d"
6921 " devices, algorithm %d\n", mdname(mddev
), conf
->level
,
6922 mddev
->raid_disks
-mddev
->degraded
, mddev
->raid_disks
,
6925 printk(KERN_ALERT
"md/raid:%s: raid level %d active with %d"
6926 " out of %d devices, algorithm %d\n",
6927 mdname(mddev
), conf
->level
,
6928 mddev
->raid_disks
- mddev
->degraded
,
6929 mddev
->raid_disks
, mddev
->new_layout
);
6931 print_raid5_conf(conf
);
6933 if (conf
->reshape_progress
!= MaxSector
) {
6934 conf
->reshape_safe
= conf
->reshape_progress
;
6935 atomic_set(&conf
->reshape_stripes
, 0);
6936 clear_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
);
6937 clear_bit(MD_RECOVERY_CHECK
, &mddev
->recovery
);
6938 set_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
);
6939 set_bit(MD_RECOVERY_RUNNING
, &mddev
->recovery
);
6940 mddev
->sync_thread
= md_register_thread(md_do_sync
, mddev
,
6944 /* Ok, everything is just fine now */
6945 if (mddev
->to_remove
== &raid5_attrs_group
)
6946 mddev
->to_remove
= NULL
;
6947 else if (mddev
->kobj
.sd
&&
6948 sysfs_create_group(&mddev
->kobj
, &raid5_attrs_group
))
6950 "raid5: failed to create sysfs attributes for %s\n",
6952 md_set_array_sectors(mddev
, raid5_size(mddev
, 0, 0));
6956 bool discard_supported
= true;
6957 /* read-ahead size must cover two whole stripes, which
6958 * is 2 * (datadisks) * chunksize where 'n' is the
6959 * number of raid devices
6961 int data_disks
= conf
->previous_raid_disks
- conf
->max_degraded
;
6962 int stripe
= data_disks
*
6963 ((mddev
->chunk_sectors
<< 9) / PAGE_SIZE
);
6964 if (mddev
->queue
->backing_dev_info
.ra_pages
< 2 * stripe
)
6965 mddev
->queue
->backing_dev_info
.ra_pages
= 2 * stripe
;
6967 chunk_size
= mddev
->chunk_sectors
<< 9;
6968 blk_queue_io_min(mddev
->queue
, chunk_size
);
6969 blk_queue_io_opt(mddev
->queue
, chunk_size
*
6970 (conf
->raid_disks
- conf
->max_degraded
));
6971 mddev
->queue
->limits
.raid_partial_stripes_expensive
= 1;
6973 * We can only discard a whole stripe. It doesn't make sense to
6974 * discard data disk but write parity disk
6976 stripe
= stripe
* PAGE_SIZE
;
6977 /* Round up to power of 2, as discard handling
6978 * currently assumes that */
6979 while ((stripe
-1) & stripe
)
6980 stripe
= (stripe
| (stripe
-1)) + 1;
6981 mddev
->queue
->limits
.discard_alignment
= stripe
;
6982 mddev
->queue
->limits
.discard_granularity
= stripe
;
6984 * unaligned part of discard request will be ignored, so can't
6985 * guarantee discard_zeroes_data
6987 mddev
->queue
->limits
.discard_zeroes_data
= 0;
6989 blk_queue_max_write_same_sectors(mddev
->queue
, 0);
6991 rdev_for_each(rdev
, mddev
) {
6992 disk_stack_limits(mddev
->gendisk
, rdev
->bdev
,
6993 rdev
->data_offset
<< 9);
6994 disk_stack_limits(mddev
->gendisk
, rdev
->bdev
,
6995 rdev
->new_data_offset
<< 9);
6997 * discard_zeroes_data is required, otherwise data
6998 * could be lost. Consider a scenario: discard a stripe
6999 * (the stripe could be inconsistent if
7000 * discard_zeroes_data is 0); write one disk of the
7001 * stripe (the stripe could be inconsistent again
7002 * depending on which disks are used to calculate
7003 * parity); the disk is broken; The stripe data of this
7006 if (!blk_queue_discard(bdev_get_queue(rdev
->bdev
)) ||
7007 !bdev_get_queue(rdev
->bdev
)->
7008 limits
.discard_zeroes_data
)
7009 discard_supported
= false;
7010 /* Unfortunately, discard_zeroes_data is not currently
7011 * a guarantee - just a hint. So we only allow DISCARD
7012 * if the sysadmin has confirmed that only safe devices
7013 * are in use by setting a module parameter.
7015 if (!devices_handle_discard_safely
) {
7016 if (discard_supported
) {
7017 pr_info("md/raid456: discard support disabled due to uncertainty.\n");
7018 pr_info("Set raid456.devices_handle_discard_safely=Y to override.\n");
7020 discard_supported
= false;
7024 if (discard_supported
&&
7025 mddev
->queue
->limits
.max_discard_sectors
>= (stripe
>> 9) &&
7026 mddev
->queue
->limits
.discard_granularity
>= stripe
)
7027 queue_flag_set_unlocked(QUEUE_FLAG_DISCARD
,
7030 queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD
,
7035 char b
[BDEVNAME_SIZE
];
7037 printk(KERN_INFO
"md/raid:%s: using device %s as journal\n",
7038 mdname(mddev
), bdevname(journal_dev
->bdev
, b
));
7039 r5l_init_log(conf
, journal_dev
);
7044 md_unregister_thread(&mddev
->thread
);
7045 print_raid5_conf(conf
);
7047 mddev
->private = NULL
;
7048 printk(KERN_ALERT
"md/raid:%s: failed to run raid set.\n", mdname(mddev
));
7052 static void raid5_free(struct mddev
*mddev
, void *priv
)
7054 struct r5conf
*conf
= priv
;
7057 mddev
->to_remove
= &raid5_attrs_group
;
7060 static void status(struct seq_file
*seq
, struct mddev
*mddev
)
7062 struct r5conf
*conf
= mddev
->private;
7065 seq_printf(seq
, " level %d, %dk chunk, algorithm %d", mddev
->level
,
7066 conf
->chunk_sectors
/ 2, mddev
->layout
);
7067 seq_printf (seq
, " [%d/%d] [", conf
->raid_disks
, conf
->raid_disks
- mddev
->degraded
);
7068 for (i
= 0; i
< conf
->raid_disks
; i
++)
7069 seq_printf (seq
, "%s",
7070 conf
->disks
[i
].rdev
&&
7071 test_bit(In_sync
, &conf
->disks
[i
].rdev
->flags
) ? "U" : "_");
7072 seq_printf (seq
, "]");
7075 static void print_raid5_conf (struct r5conf
*conf
)
7078 struct disk_info
*tmp
;
7080 printk(KERN_DEBUG
"RAID conf printout:\n");
7082 printk("(conf==NULL)\n");
7085 printk(KERN_DEBUG
" --- level:%d rd:%d wd:%d\n", conf
->level
,
7087 conf
->raid_disks
- conf
->mddev
->degraded
);
7089 for (i
= 0; i
< conf
->raid_disks
; i
++) {
7090 char b
[BDEVNAME_SIZE
];
7091 tmp
= conf
->disks
+ i
;
7093 printk(KERN_DEBUG
" disk %d, o:%d, dev:%s\n",
7094 i
, !test_bit(Faulty
, &tmp
->rdev
->flags
),
7095 bdevname(tmp
->rdev
->bdev
, b
));
7099 static int raid5_spare_active(struct mddev
*mddev
)
7102 struct r5conf
*conf
= mddev
->private;
7103 struct disk_info
*tmp
;
7105 unsigned long flags
;
7107 for (i
= 0; i
< conf
->raid_disks
; i
++) {
7108 tmp
= conf
->disks
+ i
;
7109 if (tmp
->replacement
7110 && tmp
->replacement
->recovery_offset
== MaxSector
7111 && !test_bit(Faulty
, &tmp
->replacement
->flags
)
7112 && !test_and_set_bit(In_sync
, &tmp
->replacement
->flags
)) {
7113 /* Replacement has just become active. */
7115 || !test_and_clear_bit(In_sync
, &tmp
->rdev
->flags
))
7118 /* Replaced device not technically faulty,
7119 * but we need to be sure it gets removed
7120 * and never re-added.
7122 set_bit(Faulty
, &tmp
->rdev
->flags
);
7123 sysfs_notify_dirent_safe(
7124 tmp
->rdev
->sysfs_state
);
7126 sysfs_notify_dirent_safe(tmp
->replacement
->sysfs_state
);
7127 } else if (tmp
->rdev
7128 && tmp
->rdev
->recovery_offset
== MaxSector
7129 && !test_bit(Faulty
, &tmp
->rdev
->flags
)
7130 && !test_and_set_bit(In_sync
, &tmp
->rdev
->flags
)) {
7132 sysfs_notify_dirent_safe(tmp
->rdev
->sysfs_state
);
7135 spin_lock_irqsave(&conf
->device_lock
, flags
);
7136 mddev
->degraded
= calc_degraded(conf
);
7137 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
7138 print_raid5_conf(conf
);
7142 static int raid5_remove_disk(struct mddev
*mddev
, struct md_rdev
*rdev
)
7144 struct r5conf
*conf
= mddev
->private;
7146 int number
= rdev
->raid_disk
;
7147 struct md_rdev
**rdevp
;
7148 struct disk_info
*p
= conf
->disks
+ number
;
7150 print_raid5_conf(conf
);
7151 if (test_bit(Journal
, &rdev
->flags
)) {
7153 * journal disk is not removable, but we need give a chance to
7154 * update superblock of other disks. Otherwise journal disk
7155 * will be considered as 'fresh'
7157 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
7160 if (rdev
== p
->rdev
)
7162 else if (rdev
== p
->replacement
)
7163 rdevp
= &p
->replacement
;
7167 if (number
>= conf
->raid_disks
&&
7168 conf
->reshape_progress
== MaxSector
)
7169 clear_bit(In_sync
, &rdev
->flags
);
7171 if (test_bit(In_sync
, &rdev
->flags
) ||
7172 atomic_read(&rdev
->nr_pending
)) {
7176 /* Only remove non-faulty devices if recovery
7179 if (!test_bit(Faulty
, &rdev
->flags
) &&
7180 mddev
->recovery_disabled
!= conf
->recovery_disabled
&&
7181 !has_failed(conf
) &&
7182 (!p
->replacement
|| p
->replacement
== rdev
) &&
7183 number
< conf
->raid_disks
) {
7189 if (atomic_read(&rdev
->nr_pending
)) {
7190 /* lost the race, try later */
7193 } else if (p
->replacement
) {
7194 /* We must have just cleared 'rdev' */
7195 p
->rdev
= p
->replacement
;
7196 clear_bit(Replacement
, &p
->replacement
->flags
);
7197 smp_mb(); /* Make sure other CPUs may see both as identical
7198 * but will never see neither - if they are careful
7200 p
->replacement
= NULL
;
7201 clear_bit(WantReplacement
, &rdev
->flags
);
7203 /* We might have just removed the Replacement as faulty-
7204 * clear the bit just in case
7206 clear_bit(WantReplacement
, &rdev
->flags
);
7209 print_raid5_conf(conf
);
7213 static int raid5_add_disk(struct mddev
*mddev
, struct md_rdev
*rdev
)
7215 struct r5conf
*conf
= mddev
->private;
7218 struct disk_info
*p
;
7220 int last
= conf
->raid_disks
- 1;
7222 if (test_bit(Journal
, &rdev
->flags
))
7224 if (mddev
->recovery_disabled
== conf
->recovery_disabled
)
7227 if (rdev
->saved_raid_disk
< 0 && has_failed(conf
))
7228 /* no point adding a device */
7231 if (rdev
->raid_disk
>= 0)
7232 first
= last
= rdev
->raid_disk
;
7235 * find the disk ... but prefer rdev->saved_raid_disk
7238 if (rdev
->saved_raid_disk
>= 0 &&
7239 rdev
->saved_raid_disk
>= first
&&
7240 conf
->disks
[rdev
->saved_raid_disk
].rdev
== NULL
)
7241 first
= rdev
->saved_raid_disk
;
7243 for (disk
= first
; disk
<= last
; disk
++) {
7244 p
= conf
->disks
+ disk
;
7245 if (p
->rdev
== NULL
) {
7246 clear_bit(In_sync
, &rdev
->flags
);
7247 rdev
->raid_disk
= disk
;
7249 if (rdev
->saved_raid_disk
!= disk
)
7251 rcu_assign_pointer(p
->rdev
, rdev
);
7255 for (disk
= first
; disk
<= last
; disk
++) {
7256 p
= conf
->disks
+ disk
;
7257 if (test_bit(WantReplacement
, &p
->rdev
->flags
) &&
7258 p
->replacement
== NULL
) {
7259 clear_bit(In_sync
, &rdev
->flags
);
7260 set_bit(Replacement
, &rdev
->flags
);
7261 rdev
->raid_disk
= disk
;
7264 rcu_assign_pointer(p
->replacement
, rdev
);
7269 print_raid5_conf(conf
);
7273 static int raid5_resize(struct mddev
*mddev
, sector_t sectors
)
7275 /* no resync is happening, and there is enough space
7276 * on all devices, so we can resize.
7277 * We need to make sure resync covers any new space.
7278 * If the array is shrinking we should possibly wait until
7279 * any io in the removed space completes, but it hardly seems
7283 struct r5conf
*conf
= mddev
->private;
7287 sectors
&= ~((sector_t
)conf
->chunk_sectors
- 1);
7288 newsize
= raid5_size(mddev
, sectors
, mddev
->raid_disks
);
7289 if (mddev
->external_size
&&
7290 mddev
->array_sectors
> newsize
)
7292 if (mddev
->bitmap
) {
7293 int ret
= bitmap_resize(mddev
->bitmap
, sectors
, 0, 0);
7297 md_set_array_sectors(mddev
, newsize
);
7298 set_capacity(mddev
->gendisk
, mddev
->array_sectors
);
7299 revalidate_disk(mddev
->gendisk
);
7300 if (sectors
> mddev
->dev_sectors
&&
7301 mddev
->recovery_cp
> mddev
->dev_sectors
) {
7302 mddev
->recovery_cp
= mddev
->dev_sectors
;
7303 set_bit(MD_RECOVERY_NEEDED
, &mddev
->recovery
);
7305 mddev
->dev_sectors
= sectors
;
7306 mddev
->resync_max_sectors
= sectors
;
7310 static int check_stripe_cache(struct mddev
*mddev
)
7312 /* Can only proceed if there are plenty of stripe_heads.
7313 * We need a minimum of one full stripe,, and for sensible progress
7314 * it is best to have about 4 times that.
7315 * If we require 4 times, then the default 256 4K stripe_heads will
7316 * allow for chunk sizes up to 256K, which is probably OK.
7317 * If the chunk size is greater, user-space should request more
7318 * stripe_heads first.
7320 struct r5conf
*conf
= mddev
->private;
7321 if (((mddev
->chunk_sectors
<< 9) / STRIPE_SIZE
) * 4
7322 > conf
->min_nr_stripes
||
7323 ((mddev
->new_chunk_sectors
<< 9) / STRIPE_SIZE
) * 4
7324 > conf
->min_nr_stripes
) {
7325 printk(KERN_WARNING
"md/raid:%s: reshape: not enough stripes. Needed %lu\n",
7327 ((max(mddev
->chunk_sectors
, mddev
->new_chunk_sectors
) << 9)
7334 static int check_reshape(struct mddev
*mddev
)
7336 struct r5conf
*conf
= mddev
->private;
7340 if (mddev
->delta_disks
== 0 &&
7341 mddev
->new_layout
== mddev
->layout
&&
7342 mddev
->new_chunk_sectors
== mddev
->chunk_sectors
)
7343 return 0; /* nothing to do */
7344 if (has_failed(conf
))
7346 if (mddev
->delta_disks
< 0 && mddev
->reshape_position
== MaxSector
) {
7347 /* We might be able to shrink, but the devices must
7348 * be made bigger first.
7349 * For raid6, 4 is the minimum size.
7350 * Otherwise 2 is the minimum
7353 if (mddev
->level
== 6)
7355 if (mddev
->raid_disks
+ mddev
->delta_disks
< min
)
7359 if (!check_stripe_cache(mddev
))
7362 if (mddev
->new_chunk_sectors
> mddev
->chunk_sectors
||
7363 mddev
->delta_disks
> 0)
7364 if (resize_chunks(conf
,
7365 conf
->previous_raid_disks
7366 + max(0, mddev
->delta_disks
),
7367 max(mddev
->new_chunk_sectors
,
7368 mddev
->chunk_sectors
)
7371 return resize_stripes(conf
, (conf
->previous_raid_disks
7372 + mddev
->delta_disks
));
7375 static int raid5_start_reshape(struct mddev
*mddev
)
7377 struct r5conf
*conf
= mddev
->private;
7378 struct md_rdev
*rdev
;
7380 unsigned long flags
;
7382 if (test_bit(MD_RECOVERY_RUNNING
, &mddev
->recovery
))
7385 if (!check_stripe_cache(mddev
))
7388 if (has_failed(conf
))
7391 rdev_for_each(rdev
, mddev
) {
7392 if (!test_bit(In_sync
, &rdev
->flags
)
7393 && !test_bit(Faulty
, &rdev
->flags
))
7397 if (spares
- mddev
->degraded
< mddev
->delta_disks
- conf
->max_degraded
)
7398 /* Not enough devices even to make a degraded array
7403 /* Refuse to reduce size of the array. Any reductions in
7404 * array size must be through explicit setting of array_size
7407 if (raid5_size(mddev
, 0, conf
->raid_disks
+ mddev
->delta_disks
)
7408 < mddev
->array_sectors
) {
7409 printk(KERN_ERR
"md/raid:%s: array size must be reduced "
7410 "before number of disks\n", mdname(mddev
));
7414 atomic_set(&conf
->reshape_stripes
, 0);
7415 spin_lock_irq(&conf
->device_lock
);
7416 write_seqcount_begin(&conf
->gen_lock
);
7417 conf
->previous_raid_disks
= conf
->raid_disks
;
7418 conf
->raid_disks
+= mddev
->delta_disks
;
7419 conf
->prev_chunk_sectors
= conf
->chunk_sectors
;
7420 conf
->chunk_sectors
= mddev
->new_chunk_sectors
;
7421 conf
->prev_algo
= conf
->algorithm
;
7422 conf
->algorithm
= mddev
->new_layout
;
7424 /* Code that selects data_offset needs to see the generation update
7425 * if reshape_progress has been set - so a memory barrier needed.
7428 if (mddev
->reshape_backwards
)
7429 conf
->reshape_progress
= raid5_size(mddev
, 0, 0);
7431 conf
->reshape_progress
= 0;
7432 conf
->reshape_safe
= conf
->reshape_progress
;
7433 write_seqcount_end(&conf
->gen_lock
);
7434 spin_unlock_irq(&conf
->device_lock
);
7436 /* Now make sure any requests that proceeded on the assumption
7437 * the reshape wasn't running - like Discard or Read - have
7440 mddev_suspend(mddev
);
7441 mddev_resume(mddev
);
7443 /* Add some new drives, as many as will fit.
7444 * We know there are enough to make the newly sized array work.
7445 * Don't add devices if we are reducing the number of
7446 * devices in the array. This is because it is not possible
7447 * to correctly record the "partially reconstructed" state of
7448 * such devices during the reshape and confusion could result.
7450 if (mddev
->delta_disks
>= 0) {
7451 rdev_for_each(rdev
, mddev
)
7452 if (rdev
->raid_disk
< 0 &&
7453 !test_bit(Faulty
, &rdev
->flags
)) {
7454 if (raid5_add_disk(mddev
, rdev
) == 0) {
7456 >= conf
->previous_raid_disks
)
7457 set_bit(In_sync
, &rdev
->flags
);
7459 rdev
->recovery_offset
= 0;
7461 if (sysfs_link_rdev(mddev
, rdev
))
7462 /* Failure here is OK */;
7464 } else if (rdev
->raid_disk
>= conf
->previous_raid_disks
7465 && !test_bit(Faulty
, &rdev
->flags
)) {
7466 /* This is a spare that was manually added */
7467 set_bit(In_sync
, &rdev
->flags
);
7470 /* When a reshape changes the number of devices,
7471 * ->degraded is measured against the larger of the
7472 * pre and post number of devices.
7474 spin_lock_irqsave(&conf
->device_lock
, flags
);
7475 mddev
->degraded
= calc_degraded(conf
);
7476 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
7478 mddev
->raid_disks
= conf
->raid_disks
;
7479 mddev
->reshape_position
= conf
->reshape_progress
;
7480 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
7482 clear_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
);
7483 clear_bit(MD_RECOVERY_CHECK
, &mddev
->recovery
);
7484 clear_bit(MD_RECOVERY_DONE
, &mddev
->recovery
);
7485 set_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
);
7486 set_bit(MD_RECOVERY_RUNNING
, &mddev
->recovery
);
7487 mddev
->sync_thread
= md_register_thread(md_do_sync
, mddev
,
7489 if (!mddev
->sync_thread
) {
7490 mddev
->recovery
= 0;
7491 spin_lock_irq(&conf
->device_lock
);
7492 write_seqcount_begin(&conf
->gen_lock
);
7493 mddev
->raid_disks
= conf
->raid_disks
= conf
->previous_raid_disks
;
7494 mddev
->new_chunk_sectors
=
7495 conf
->chunk_sectors
= conf
->prev_chunk_sectors
;
7496 mddev
->new_layout
= conf
->algorithm
= conf
->prev_algo
;
7497 rdev_for_each(rdev
, mddev
)
7498 rdev
->new_data_offset
= rdev
->data_offset
;
7500 conf
->generation
--;
7501 conf
->reshape_progress
= MaxSector
;
7502 mddev
->reshape_position
= MaxSector
;
7503 write_seqcount_end(&conf
->gen_lock
);
7504 spin_unlock_irq(&conf
->device_lock
);
7507 conf
->reshape_checkpoint
= jiffies
;
7508 md_wakeup_thread(mddev
->sync_thread
);
7509 md_new_event(mddev
);
7513 /* This is called from the reshape thread and should make any
7514 * changes needed in 'conf'
7516 static void end_reshape(struct r5conf
*conf
)
7519 if (!test_bit(MD_RECOVERY_INTR
, &conf
->mddev
->recovery
)) {
7520 struct md_rdev
*rdev
;
7522 spin_lock_irq(&conf
->device_lock
);
7523 conf
->previous_raid_disks
= conf
->raid_disks
;
7524 rdev_for_each(rdev
, conf
->mddev
)
7525 rdev
->data_offset
= rdev
->new_data_offset
;
7527 conf
->reshape_progress
= MaxSector
;
7528 conf
->mddev
->reshape_position
= MaxSector
;
7529 spin_unlock_irq(&conf
->device_lock
);
7530 wake_up(&conf
->wait_for_overlap
);
7532 /* read-ahead size must cover two whole stripes, which is
7533 * 2 * (datadisks) * chunksize where 'n' is the number of raid devices
7535 if (conf
->mddev
->queue
) {
7536 int data_disks
= conf
->raid_disks
- conf
->max_degraded
;
7537 int stripe
= data_disks
* ((conf
->chunk_sectors
<< 9)
7539 if (conf
->mddev
->queue
->backing_dev_info
.ra_pages
< 2 * stripe
)
7540 conf
->mddev
->queue
->backing_dev_info
.ra_pages
= 2 * stripe
;
7545 /* This is called from the raid5d thread with mddev_lock held.
7546 * It makes config changes to the device.
7548 static void raid5_finish_reshape(struct mddev
*mddev
)
7550 struct r5conf
*conf
= mddev
->private;
7552 if (!test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
)) {
7554 if (mddev
->delta_disks
> 0) {
7555 md_set_array_sectors(mddev
, raid5_size(mddev
, 0, 0));
7556 set_capacity(mddev
->gendisk
, mddev
->array_sectors
);
7557 revalidate_disk(mddev
->gendisk
);
7560 spin_lock_irq(&conf
->device_lock
);
7561 mddev
->degraded
= calc_degraded(conf
);
7562 spin_unlock_irq(&conf
->device_lock
);
7563 for (d
= conf
->raid_disks
;
7564 d
< conf
->raid_disks
- mddev
->delta_disks
;
7566 struct md_rdev
*rdev
= conf
->disks
[d
].rdev
;
7568 clear_bit(In_sync
, &rdev
->flags
);
7569 rdev
= conf
->disks
[d
].replacement
;
7571 clear_bit(In_sync
, &rdev
->flags
);
7574 mddev
->layout
= conf
->algorithm
;
7575 mddev
->chunk_sectors
= conf
->chunk_sectors
;
7576 mddev
->reshape_position
= MaxSector
;
7577 mddev
->delta_disks
= 0;
7578 mddev
->reshape_backwards
= 0;
7582 static void raid5_quiesce(struct mddev
*mddev
, int state
)
7584 struct r5conf
*conf
= mddev
->private;
7587 case 2: /* resume for a suspend */
7588 wake_up(&conf
->wait_for_overlap
);
7591 case 1: /* stop all writes */
7592 lock_all_device_hash_locks_irq(conf
);
7593 /* '2' tells resync/reshape to pause so that all
7594 * active stripes can drain
7597 wait_event_cmd(conf
->wait_for_quiescent
,
7598 atomic_read(&conf
->active_stripes
) == 0 &&
7599 atomic_read(&conf
->active_aligned_reads
) == 0,
7600 unlock_all_device_hash_locks_irq(conf
),
7601 lock_all_device_hash_locks_irq(conf
));
7603 unlock_all_device_hash_locks_irq(conf
);
7604 /* allow reshape to continue */
7605 wake_up(&conf
->wait_for_overlap
);
7608 case 0: /* re-enable writes */
7609 lock_all_device_hash_locks_irq(conf
);
7611 wake_up(&conf
->wait_for_quiescent
);
7612 wake_up(&conf
->wait_for_overlap
);
7613 unlock_all_device_hash_locks_irq(conf
);
7616 r5l_quiesce(conf
->log
, state
);
7619 static void *raid45_takeover_raid0(struct mddev
*mddev
, int level
)
7621 struct r0conf
*raid0_conf
= mddev
->private;
7624 /* for raid0 takeover only one zone is supported */
7625 if (raid0_conf
->nr_strip_zones
> 1) {
7626 printk(KERN_ERR
"md/raid:%s: cannot takeover raid0 with more than one zone.\n",
7628 return ERR_PTR(-EINVAL
);
7631 sectors
= raid0_conf
->strip_zone
[0].zone_end
;
7632 sector_div(sectors
, raid0_conf
->strip_zone
[0].nb_dev
);
7633 mddev
->dev_sectors
= sectors
;
7634 mddev
->new_level
= level
;
7635 mddev
->new_layout
= ALGORITHM_PARITY_N
;
7636 mddev
->new_chunk_sectors
= mddev
->chunk_sectors
;
7637 mddev
->raid_disks
+= 1;
7638 mddev
->delta_disks
= 1;
7639 /* make sure it will be not marked as dirty */
7640 mddev
->recovery_cp
= MaxSector
;
7642 return setup_conf(mddev
);
7645 static void *raid5_takeover_raid1(struct mddev
*mddev
)
7649 if (mddev
->raid_disks
!= 2 ||
7650 mddev
->degraded
> 1)
7651 return ERR_PTR(-EINVAL
);
7653 /* Should check if there are write-behind devices? */
7655 chunksect
= 64*2; /* 64K by default */
7657 /* The array must be an exact multiple of chunksize */
7658 while (chunksect
&& (mddev
->array_sectors
& (chunksect
-1)))
7661 if ((chunksect
<<9) < STRIPE_SIZE
)
7662 /* array size does not allow a suitable chunk size */
7663 return ERR_PTR(-EINVAL
);
7665 mddev
->new_level
= 5;
7666 mddev
->new_layout
= ALGORITHM_LEFT_SYMMETRIC
;
7667 mddev
->new_chunk_sectors
= chunksect
;
7669 return setup_conf(mddev
);
7672 static void *raid5_takeover_raid6(struct mddev
*mddev
)
7676 switch (mddev
->layout
) {
7677 case ALGORITHM_LEFT_ASYMMETRIC_6
:
7678 new_layout
= ALGORITHM_LEFT_ASYMMETRIC
;
7680 case ALGORITHM_RIGHT_ASYMMETRIC_6
:
7681 new_layout
= ALGORITHM_RIGHT_ASYMMETRIC
;
7683 case ALGORITHM_LEFT_SYMMETRIC_6
:
7684 new_layout
= ALGORITHM_LEFT_SYMMETRIC
;
7686 case ALGORITHM_RIGHT_SYMMETRIC_6
:
7687 new_layout
= ALGORITHM_RIGHT_SYMMETRIC
;
7689 case ALGORITHM_PARITY_0_6
:
7690 new_layout
= ALGORITHM_PARITY_0
;
7692 case ALGORITHM_PARITY_N
:
7693 new_layout
= ALGORITHM_PARITY_N
;
7696 return ERR_PTR(-EINVAL
);
7698 mddev
->new_level
= 5;
7699 mddev
->new_layout
= new_layout
;
7700 mddev
->delta_disks
= -1;
7701 mddev
->raid_disks
-= 1;
7702 return setup_conf(mddev
);
7705 static int raid5_check_reshape(struct mddev
*mddev
)
7707 /* For a 2-drive array, the layout and chunk size can be changed
7708 * immediately as not restriping is needed.
7709 * For larger arrays we record the new value - after validation
7710 * to be used by a reshape pass.
7712 struct r5conf
*conf
= mddev
->private;
7713 int new_chunk
= mddev
->new_chunk_sectors
;
7715 if (mddev
->new_layout
>= 0 && !algorithm_valid_raid5(mddev
->new_layout
))
7717 if (new_chunk
> 0) {
7718 if (!is_power_of_2(new_chunk
))
7720 if (new_chunk
< (PAGE_SIZE
>>9))
7722 if (mddev
->array_sectors
& (new_chunk
-1))
7723 /* not factor of array size */
7727 /* They look valid */
7729 if (mddev
->raid_disks
== 2) {
7730 /* can make the change immediately */
7731 if (mddev
->new_layout
>= 0) {
7732 conf
->algorithm
= mddev
->new_layout
;
7733 mddev
->layout
= mddev
->new_layout
;
7735 if (new_chunk
> 0) {
7736 conf
->chunk_sectors
= new_chunk
;
7737 mddev
->chunk_sectors
= new_chunk
;
7739 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
7740 md_wakeup_thread(mddev
->thread
);
7742 return check_reshape(mddev
);
7745 static int raid6_check_reshape(struct mddev
*mddev
)
7747 int new_chunk
= mddev
->new_chunk_sectors
;
7749 if (mddev
->new_layout
>= 0 && !algorithm_valid_raid6(mddev
->new_layout
))
7751 if (new_chunk
> 0) {
7752 if (!is_power_of_2(new_chunk
))
7754 if (new_chunk
< (PAGE_SIZE
>> 9))
7756 if (mddev
->array_sectors
& (new_chunk
-1))
7757 /* not factor of array size */
7761 /* They look valid */
7762 return check_reshape(mddev
);
7765 static void *raid5_takeover(struct mddev
*mddev
)
7767 /* raid5 can take over:
7768 * raid0 - if there is only one strip zone - make it a raid4 layout
7769 * raid1 - if there are two drives. We need to know the chunk size
7770 * raid4 - trivial - just use a raid4 layout.
7771 * raid6 - Providing it is a *_6 layout
7773 if (mddev
->level
== 0)
7774 return raid45_takeover_raid0(mddev
, 5);
7775 if (mddev
->level
== 1)
7776 return raid5_takeover_raid1(mddev
);
7777 if (mddev
->level
== 4) {
7778 mddev
->new_layout
= ALGORITHM_PARITY_N
;
7779 mddev
->new_level
= 5;
7780 return setup_conf(mddev
);
7782 if (mddev
->level
== 6)
7783 return raid5_takeover_raid6(mddev
);
7785 return ERR_PTR(-EINVAL
);
7788 static void *raid4_takeover(struct mddev
*mddev
)
7790 /* raid4 can take over:
7791 * raid0 - if there is only one strip zone
7792 * raid5 - if layout is right
7794 if (mddev
->level
== 0)
7795 return raid45_takeover_raid0(mddev
, 4);
7796 if (mddev
->level
== 5 &&
7797 mddev
->layout
== ALGORITHM_PARITY_N
) {
7798 mddev
->new_layout
= 0;
7799 mddev
->new_level
= 4;
7800 return setup_conf(mddev
);
7802 return ERR_PTR(-EINVAL
);
7805 static struct md_personality raid5_personality
;
7807 static void *raid6_takeover(struct mddev
*mddev
)
7809 /* Currently can only take over a raid5. We map the
7810 * personality to an equivalent raid6 personality
7811 * with the Q block at the end.
7815 if (mddev
->pers
!= &raid5_personality
)
7816 return ERR_PTR(-EINVAL
);
7817 if (mddev
->degraded
> 1)
7818 return ERR_PTR(-EINVAL
);
7819 if (mddev
->raid_disks
> 253)
7820 return ERR_PTR(-EINVAL
);
7821 if (mddev
->raid_disks
< 3)
7822 return ERR_PTR(-EINVAL
);
7824 switch (mddev
->layout
) {
7825 case ALGORITHM_LEFT_ASYMMETRIC
:
7826 new_layout
= ALGORITHM_LEFT_ASYMMETRIC_6
;
7828 case ALGORITHM_RIGHT_ASYMMETRIC
:
7829 new_layout
= ALGORITHM_RIGHT_ASYMMETRIC_6
;
7831 case ALGORITHM_LEFT_SYMMETRIC
:
7832 new_layout
= ALGORITHM_LEFT_SYMMETRIC_6
;
7834 case ALGORITHM_RIGHT_SYMMETRIC
:
7835 new_layout
= ALGORITHM_RIGHT_SYMMETRIC_6
;
7837 case ALGORITHM_PARITY_0
:
7838 new_layout
= ALGORITHM_PARITY_0_6
;
7840 case ALGORITHM_PARITY_N
:
7841 new_layout
= ALGORITHM_PARITY_N
;
7844 return ERR_PTR(-EINVAL
);
7846 mddev
->new_level
= 6;
7847 mddev
->new_layout
= new_layout
;
7848 mddev
->delta_disks
= 1;
7849 mddev
->raid_disks
+= 1;
7850 return setup_conf(mddev
);
7853 static struct md_personality raid6_personality
=
7857 .owner
= THIS_MODULE
,
7858 .make_request
= make_request
,
7862 .error_handler
= error
,
7863 .hot_add_disk
= raid5_add_disk
,
7864 .hot_remove_disk
= raid5_remove_disk
,
7865 .spare_active
= raid5_spare_active
,
7866 .sync_request
= sync_request
,
7867 .resize
= raid5_resize
,
7869 .check_reshape
= raid6_check_reshape
,
7870 .start_reshape
= raid5_start_reshape
,
7871 .finish_reshape
= raid5_finish_reshape
,
7872 .quiesce
= raid5_quiesce
,
7873 .takeover
= raid6_takeover
,
7874 .congested
= raid5_congested
,
7876 static struct md_personality raid5_personality
=
7880 .owner
= THIS_MODULE
,
7881 .make_request
= make_request
,
7885 .error_handler
= error
,
7886 .hot_add_disk
= raid5_add_disk
,
7887 .hot_remove_disk
= raid5_remove_disk
,
7888 .spare_active
= raid5_spare_active
,
7889 .sync_request
= sync_request
,
7890 .resize
= raid5_resize
,
7892 .check_reshape
= raid5_check_reshape
,
7893 .start_reshape
= raid5_start_reshape
,
7894 .finish_reshape
= raid5_finish_reshape
,
7895 .quiesce
= raid5_quiesce
,
7896 .takeover
= raid5_takeover
,
7897 .congested
= raid5_congested
,
7900 static struct md_personality raid4_personality
=
7904 .owner
= THIS_MODULE
,
7905 .make_request
= make_request
,
7909 .error_handler
= error
,
7910 .hot_add_disk
= raid5_add_disk
,
7911 .hot_remove_disk
= raid5_remove_disk
,
7912 .spare_active
= raid5_spare_active
,
7913 .sync_request
= sync_request
,
7914 .resize
= raid5_resize
,
7916 .check_reshape
= raid5_check_reshape
,
7917 .start_reshape
= raid5_start_reshape
,
7918 .finish_reshape
= raid5_finish_reshape
,
7919 .quiesce
= raid5_quiesce
,
7920 .takeover
= raid4_takeover
,
7921 .congested
= raid5_congested
,
7924 static int __init
raid5_init(void)
7926 raid5_wq
= alloc_workqueue("raid5wq",
7927 WQ_UNBOUND
|WQ_MEM_RECLAIM
|WQ_CPU_INTENSIVE
|WQ_SYSFS
, 0);
7930 register_md_personality(&raid6_personality
);
7931 register_md_personality(&raid5_personality
);
7932 register_md_personality(&raid4_personality
);
7936 static void raid5_exit(void)
7938 unregister_md_personality(&raid6_personality
);
7939 unregister_md_personality(&raid5_personality
);
7940 unregister_md_personality(&raid4_personality
);
7941 destroy_workqueue(raid5_wq
);
7944 module_init(raid5_init
);
7945 module_exit(raid5_exit
);
7946 MODULE_LICENSE("GPL");
7947 MODULE_DESCRIPTION("RAID4/5/6 (striping with parity) personality for MD");
7948 MODULE_ALIAS("md-personality-4"); /* RAID5 */
7949 MODULE_ALIAS("md-raid5");
7950 MODULE_ALIAS("md-raid4");
7951 MODULE_ALIAS("md-level-5");
7952 MODULE_ALIAS("md-level-4");
7953 MODULE_ALIAS("md-personality-8"); /* RAID6 */
7954 MODULE_ALIAS("md-raid6");
7955 MODULE_ALIAS("md-level-6");
7957 /* This used to be two separate modules, they were: */
7958 MODULE_ALIAS("raid5");
7959 MODULE_ALIAS("raid6");