2 * raid5.c : Multiple Devices driver for Linux
3 * Copyright (C) 1996, 1997 Ingo Molnar, Miguel de Icaza, Gadi Oxman
4 * Copyright (C) 1999, 2000 Ingo Molnar
5 * Copyright (C) 2002, 2003 H. Peter Anvin
7 * RAID-4/5/6 management functions.
8 * Thanks to Penguin Computing for making the RAID-6 development possible
9 * by donating a test server!
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2, or (at your option)
16 * You should have received a copy of the GNU General Public License
17 * (for example /usr/src/linux/COPYING); if not, write to the Free
18 * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24 * The sequencing for updating the bitmap reliably is a little
25 * subtle (and I got it wrong the first time) so it deserves some
28 * We group bitmap updates into batches. Each batch has a number.
29 * We may write out several batches at once, but that isn't very important.
30 * conf->seq_write is the number of the last batch successfully written.
31 * conf->seq_flush is the number of the last batch that was closed to
33 * When we discover that we will need to write to any block in a stripe
34 * (in add_stripe_bio) we update the in-memory bitmap and record in sh->bm_seq
35 * the number of the batch it will be in. This is seq_flush+1.
36 * When we are ready to do a write, if that batch hasn't been written yet,
37 * we plug the array and queue the stripe for later.
38 * When an unplug happens, we increment bm_flush, thus closing the current
40 * When we notice that bm_flush > bm_write, we write out all pending updates
41 * to the bitmap, and advance bm_write to where bm_flush was.
42 * This may occasionally write a bit out twice, but is sure never to
46 #include <linux/blkdev.h>
47 #include <linux/kthread.h>
48 #include <linux/raid/pq.h>
49 #include <linux/async_tx.h>
50 #include <linux/module.h>
51 #include <linux/async.h>
52 #include <linux/seq_file.h>
53 #include <linux/cpu.h>
54 #include <linux/slab.h>
55 #include <linux/ratelimit.h>
56 #include <linux/nodemask.h>
57 #include <linux/flex_array.h>
58 #include <trace/events/block.h>
65 #define cpu_to_group(cpu) cpu_to_node(cpu)
66 #define ANY_GROUP NUMA_NO_NODE
68 static bool devices_handle_discard_safely
= false;
69 module_param(devices_handle_discard_safely
, bool, 0644);
70 MODULE_PARM_DESC(devices_handle_discard_safely
,
71 "Set to Y if all devices in each array reliably return zeroes on reads from discarded regions");
72 static struct workqueue_struct
*raid5_wq
;
77 #define NR_STRIPES 256
78 #define STRIPE_SIZE PAGE_SIZE
79 #define STRIPE_SHIFT (PAGE_SHIFT - 9)
80 #define STRIPE_SECTORS (STRIPE_SIZE>>9)
81 #define IO_THRESHOLD 1
82 #define BYPASS_THRESHOLD 1
83 #define NR_HASH (PAGE_SIZE / sizeof(struct hlist_head))
84 #define HASH_MASK (NR_HASH - 1)
85 #define MAX_STRIPE_BATCH 8
87 static inline struct hlist_head
*stripe_hash(struct r5conf
*conf
, sector_t sect
)
89 int hash
= (sect
>> STRIPE_SHIFT
) & HASH_MASK
;
90 return &conf
->stripe_hashtbl
[hash
];
93 static inline int stripe_hash_locks_hash(sector_t sect
)
95 return (sect
>> STRIPE_SHIFT
) & STRIPE_HASH_LOCKS_MASK
;
98 static inline void lock_device_hash_lock(struct r5conf
*conf
, int hash
)
100 spin_lock_irq(conf
->hash_locks
+ hash
);
101 spin_lock(&conf
->device_lock
);
104 static inline void unlock_device_hash_lock(struct r5conf
*conf
, int hash
)
106 spin_unlock(&conf
->device_lock
);
107 spin_unlock_irq(conf
->hash_locks
+ hash
);
110 static inline void lock_all_device_hash_locks_irq(struct r5conf
*conf
)
114 spin_lock(conf
->hash_locks
);
115 for (i
= 1; i
< NR_STRIPE_HASH_LOCKS
; i
++)
116 spin_lock_nest_lock(conf
->hash_locks
+ i
, conf
->hash_locks
);
117 spin_lock(&conf
->device_lock
);
120 static inline void unlock_all_device_hash_locks_irq(struct r5conf
*conf
)
123 spin_unlock(&conf
->device_lock
);
124 for (i
= NR_STRIPE_HASH_LOCKS
; i
; i
--)
125 spin_unlock(conf
->hash_locks
+ i
- 1);
129 /* bio's attached to a stripe+device for I/O are linked together in bi_sector
130 * order without overlap. There may be several bio's per stripe+device, and
131 * a bio could span several devices.
132 * When walking this list for a particular stripe+device, we must never proceed
133 * beyond a bio that extends past this device, as the next bio might no longer
135 * This function is used to determine the 'next' bio in the list, given the sector
136 * of the current stripe+device
138 static inline struct bio
*r5_next_bio(struct bio
*bio
, sector_t sector
)
140 int sectors
= bio_sectors(bio
);
141 if (bio
->bi_iter
.bi_sector
+ sectors
< sector
+ STRIPE_SECTORS
)
148 * We maintain a biased count of active stripes in the bottom 16 bits of
149 * bi_phys_segments, and a count of processed stripes in the upper 16 bits
151 static inline int raid5_bi_processed_stripes(struct bio
*bio
)
153 atomic_t
*segments
= (atomic_t
*)&bio
->bi_phys_segments
;
154 return (atomic_read(segments
) >> 16) & 0xffff;
157 static inline int raid5_dec_bi_active_stripes(struct bio
*bio
)
159 atomic_t
*segments
= (atomic_t
*)&bio
->bi_phys_segments
;
160 return atomic_sub_return(1, segments
) & 0xffff;
163 static inline void raid5_inc_bi_active_stripes(struct bio
*bio
)
165 atomic_t
*segments
= (atomic_t
*)&bio
->bi_phys_segments
;
166 atomic_inc(segments
);
169 static inline void raid5_set_bi_processed_stripes(struct bio
*bio
,
172 atomic_t
*segments
= (atomic_t
*)&bio
->bi_phys_segments
;
176 old
= atomic_read(segments
);
177 new = (old
& 0xffff) | (cnt
<< 16);
178 } while (atomic_cmpxchg(segments
, old
, new) != old
);
181 static inline void raid5_set_bi_stripes(struct bio
*bio
, unsigned int cnt
)
183 atomic_t
*segments
= (atomic_t
*)&bio
->bi_phys_segments
;
184 atomic_set(segments
, cnt
);
187 /* Find first data disk in a raid6 stripe */
188 static inline int raid6_d0(struct stripe_head
*sh
)
191 /* ddf always start from first device */
193 /* md starts just after Q block */
194 if (sh
->qd_idx
== sh
->disks
- 1)
197 return sh
->qd_idx
+ 1;
199 static inline int raid6_next_disk(int disk
, int raid_disks
)
202 return (disk
< raid_disks
) ? disk
: 0;
205 /* When walking through the disks in a raid5, starting at raid6_d0,
206 * We need to map each disk to a 'slot', where the data disks are slot
207 * 0 .. raid_disks-3, the parity disk is raid_disks-2 and the Q disk
208 * is raid_disks-1. This help does that mapping.
210 static int raid6_idx_to_slot(int idx
, struct stripe_head
*sh
,
211 int *count
, int syndrome_disks
)
217 if (idx
== sh
->pd_idx
)
218 return syndrome_disks
;
219 if (idx
== sh
->qd_idx
)
220 return syndrome_disks
+ 1;
226 static void return_io(struct bio
*return_bi
)
228 struct bio
*bi
= return_bi
;
231 return_bi
= bi
->bi_next
;
233 bi
->bi_iter
.bi_size
= 0;
234 trace_block_bio_complete(bdev_get_queue(bi
->bi_bdev
),
241 static void print_raid5_conf (struct r5conf
*conf
);
243 static int stripe_operations_active(struct stripe_head
*sh
)
245 return sh
->check_state
|| sh
->reconstruct_state
||
246 test_bit(STRIPE_BIOFILL_RUN
, &sh
->state
) ||
247 test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
250 static void raid5_wakeup_stripe_thread(struct stripe_head
*sh
)
252 struct r5conf
*conf
= sh
->raid_conf
;
253 struct r5worker_group
*group
;
255 int i
, cpu
= sh
->cpu
;
257 if (!cpu_online(cpu
)) {
258 cpu
= cpumask_any(cpu_online_mask
);
262 if (list_empty(&sh
->lru
)) {
263 struct r5worker_group
*group
;
264 group
= conf
->worker_groups
+ cpu_to_group(cpu
);
265 list_add_tail(&sh
->lru
, &group
->handle_list
);
266 group
->stripes_cnt
++;
270 if (conf
->worker_cnt_per_group
== 0) {
271 md_wakeup_thread(conf
->mddev
->thread
);
275 group
= conf
->worker_groups
+ cpu_to_group(sh
->cpu
);
277 group
->workers
[0].working
= true;
278 /* at least one worker should run to avoid race */
279 queue_work_on(sh
->cpu
, raid5_wq
, &group
->workers
[0].work
);
281 thread_cnt
= group
->stripes_cnt
/ MAX_STRIPE_BATCH
- 1;
282 /* wakeup more workers */
283 for (i
= 1; i
< conf
->worker_cnt_per_group
&& thread_cnt
> 0; i
++) {
284 if (group
->workers
[i
].working
== false) {
285 group
->workers
[i
].working
= true;
286 queue_work_on(sh
->cpu
, raid5_wq
,
287 &group
->workers
[i
].work
);
293 static void do_release_stripe(struct r5conf
*conf
, struct stripe_head
*sh
,
294 struct list_head
*temp_inactive_list
)
296 BUG_ON(!list_empty(&sh
->lru
));
297 BUG_ON(atomic_read(&conf
->active_stripes
)==0);
298 if (test_bit(STRIPE_HANDLE
, &sh
->state
)) {
299 if (test_bit(STRIPE_DELAYED
, &sh
->state
) &&
300 !test_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
301 list_add_tail(&sh
->lru
, &conf
->delayed_list
);
302 else if (test_bit(STRIPE_BIT_DELAY
, &sh
->state
) &&
303 sh
->bm_seq
- conf
->seq_write
> 0)
304 list_add_tail(&sh
->lru
, &conf
->bitmap_list
);
306 clear_bit(STRIPE_DELAYED
, &sh
->state
);
307 clear_bit(STRIPE_BIT_DELAY
, &sh
->state
);
308 if (conf
->worker_cnt_per_group
== 0) {
309 list_add_tail(&sh
->lru
, &conf
->handle_list
);
311 raid5_wakeup_stripe_thread(sh
);
315 md_wakeup_thread(conf
->mddev
->thread
);
317 BUG_ON(stripe_operations_active(sh
));
318 if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
319 if (atomic_dec_return(&conf
->preread_active_stripes
)
321 md_wakeup_thread(conf
->mddev
->thread
);
322 atomic_dec(&conf
->active_stripes
);
323 if (!test_bit(STRIPE_EXPANDING
, &sh
->state
))
324 list_add_tail(&sh
->lru
, temp_inactive_list
);
328 static void __release_stripe(struct r5conf
*conf
, struct stripe_head
*sh
,
329 struct list_head
*temp_inactive_list
)
331 if (atomic_dec_and_test(&sh
->count
))
332 do_release_stripe(conf
, sh
, temp_inactive_list
);
336 * @hash could be NR_STRIPE_HASH_LOCKS, then we have a list of inactive_list
338 * Be careful: Only one task can add/delete stripes from temp_inactive_list at
339 * given time. Adding stripes only takes device lock, while deleting stripes
340 * only takes hash lock.
342 static void release_inactive_stripe_list(struct r5conf
*conf
,
343 struct list_head
*temp_inactive_list
,
347 unsigned long do_wakeup
= 0;
351 if (hash
== NR_STRIPE_HASH_LOCKS
) {
352 size
= NR_STRIPE_HASH_LOCKS
;
353 hash
= NR_STRIPE_HASH_LOCKS
- 1;
357 struct list_head
*list
= &temp_inactive_list
[size
- 1];
360 * We don't hold any lock here yet, get_active_stripe() might
361 * remove stripes from the list
363 if (!list_empty_careful(list
)) {
364 spin_lock_irqsave(conf
->hash_locks
+ hash
, flags
);
365 if (list_empty(conf
->inactive_list
+ hash
) &&
367 atomic_dec(&conf
->empty_inactive_list_nr
);
368 list_splice_tail_init(list
, conf
->inactive_list
+ hash
);
369 do_wakeup
|= 1 << hash
;
370 spin_unlock_irqrestore(conf
->hash_locks
+ hash
, flags
);
376 for (i
= 0; i
< NR_STRIPE_HASH_LOCKS
; i
++) {
377 if (do_wakeup
& (1 << i
))
378 wake_up(&conf
->wait_for_stripe
[i
]);
382 if (atomic_read(&conf
->active_stripes
) == 0)
383 wake_up(&conf
->wait_for_quiescent
);
384 if (conf
->retry_read_aligned
)
385 md_wakeup_thread(conf
->mddev
->thread
);
389 /* should hold conf->device_lock already */
390 static int release_stripe_list(struct r5conf
*conf
,
391 struct list_head
*temp_inactive_list
)
393 struct stripe_head
*sh
;
395 struct llist_node
*head
;
397 head
= llist_del_all(&conf
->released_stripes
);
398 head
= llist_reverse_order(head
);
402 sh
= llist_entry(head
, struct stripe_head
, release_list
);
403 head
= llist_next(head
);
404 /* sh could be readded after STRIPE_ON_RELEASE_LIST is cleard */
406 clear_bit(STRIPE_ON_RELEASE_LIST
, &sh
->state
);
408 * Don't worry the bit is set here, because if the bit is set
409 * again, the count is always > 1. This is true for
410 * STRIPE_ON_UNPLUG_LIST bit too.
412 hash
= sh
->hash_lock_index
;
413 __release_stripe(conf
, sh
, &temp_inactive_list
[hash
]);
420 static void release_stripe(struct stripe_head
*sh
)
422 struct r5conf
*conf
= sh
->raid_conf
;
424 struct list_head list
;
428 /* Avoid release_list until the last reference.
430 if (atomic_add_unless(&sh
->count
, -1, 1))
433 if (unlikely(!conf
->mddev
->thread
) ||
434 test_and_set_bit(STRIPE_ON_RELEASE_LIST
, &sh
->state
))
436 wakeup
= llist_add(&sh
->release_list
, &conf
->released_stripes
);
438 md_wakeup_thread(conf
->mddev
->thread
);
441 local_irq_save(flags
);
442 /* we are ok here if STRIPE_ON_RELEASE_LIST is set or not */
443 if (atomic_dec_and_lock(&sh
->count
, &conf
->device_lock
)) {
444 INIT_LIST_HEAD(&list
);
445 hash
= sh
->hash_lock_index
;
446 do_release_stripe(conf
, sh
, &list
);
447 spin_unlock(&conf
->device_lock
);
448 release_inactive_stripe_list(conf
, &list
, hash
);
450 local_irq_restore(flags
);
453 static inline void remove_hash(struct stripe_head
*sh
)
455 pr_debug("remove_hash(), stripe %llu\n",
456 (unsigned long long)sh
->sector
);
458 hlist_del_init(&sh
->hash
);
461 static inline void insert_hash(struct r5conf
*conf
, struct stripe_head
*sh
)
463 struct hlist_head
*hp
= stripe_hash(conf
, sh
->sector
);
465 pr_debug("insert_hash(), stripe %llu\n",
466 (unsigned long long)sh
->sector
);
468 hlist_add_head(&sh
->hash
, hp
);
471 /* find an idle stripe, make sure it is unhashed, and return it. */
472 static struct stripe_head
*get_free_stripe(struct r5conf
*conf
, int hash
)
474 struct stripe_head
*sh
= NULL
;
475 struct list_head
*first
;
477 if (list_empty(conf
->inactive_list
+ hash
))
479 first
= (conf
->inactive_list
+ hash
)->next
;
480 sh
= list_entry(first
, struct stripe_head
, lru
);
481 list_del_init(first
);
483 atomic_inc(&conf
->active_stripes
);
484 BUG_ON(hash
!= sh
->hash_lock_index
);
485 if (list_empty(conf
->inactive_list
+ hash
))
486 atomic_inc(&conf
->empty_inactive_list_nr
);
491 static void shrink_buffers(struct stripe_head
*sh
)
495 int num
= sh
->raid_conf
->pool_size
;
497 for (i
= 0; i
< num
; i
++) {
498 WARN_ON(sh
->dev
[i
].page
!= sh
->dev
[i
].orig_page
);
502 sh
->dev
[i
].page
= NULL
;
507 static int grow_buffers(struct stripe_head
*sh
, gfp_t gfp
)
510 int num
= sh
->raid_conf
->pool_size
;
512 for (i
= 0; i
< num
; i
++) {
515 if (!(page
= alloc_page(gfp
))) {
518 sh
->dev
[i
].page
= page
;
519 sh
->dev
[i
].orig_page
= page
;
524 static void raid5_build_block(struct stripe_head
*sh
, int i
, int previous
);
525 static void stripe_set_idx(sector_t stripe
, struct r5conf
*conf
, int previous
,
526 struct stripe_head
*sh
);
528 static void init_stripe(struct stripe_head
*sh
, sector_t sector
, int previous
)
530 struct r5conf
*conf
= sh
->raid_conf
;
533 BUG_ON(atomic_read(&sh
->count
) != 0);
534 BUG_ON(test_bit(STRIPE_HANDLE
, &sh
->state
));
535 BUG_ON(stripe_operations_active(sh
));
536 BUG_ON(sh
->batch_head
);
538 pr_debug("init_stripe called, stripe %llu\n",
539 (unsigned long long)sector
);
541 seq
= read_seqcount_begin(&conf
->gen_lock
);
542 sh
->generation
= conf
->generation
- previous
;
543 sh
->disks
= previous
? conf
->previous_raid_disks
: conf
->raid_disks
;
545 stripe_set_idx(sector
, conf
, previous
, sh
);
548 for (i
= sh
->disks
; i
--; ) {
549 struct r5dev
*dev
= &sh
->dev
[i
];
551 if (dev
->toread
|| dev
->read
|| dev
->towrite
|| dev
->written
||
552 test_bit(R5_LOCKED
, &dev
->flags
)) {
553 printk(KERN_ERR
"sector=%llx i=%d %p %p %p %p %d\n",
554 (unsigned long long)sh
->sector
, i
, dev
->toread
,
555 dev
->read
, dev
->towrite
, dev
->written
,
556 test_bit(R5_LOCKED
, &dev
->flags
));
560 raid5_build_block(sh
, i
, previous
);
562 if (read_seqcount_retry(&conf
->gen_lock
, seq
))
564 sh
->overwrite_disks
= 0;
565 insert_hash(conf
, sh
);
566 sh
->cpu
= smp_processor_id();
567 set_bit(STRIPE_BATCH_READY
, &sh
->state
);
570 static struct stripe_head
*__find_stripe(struct r5conf
*conf
, sector_t sector
,
573 struct stripe_head
*sh
;
575 pr_debug("__find_stripe, sector %llu\n", (unsigned long long)sector
);
576 hlist_for_each_entry(sh
, stripe_hash(conf
, sector
), hash
)
577 if (sh
->sector
== sector
&& sh
->generation
== generation
)
579 pr_debug("__stripe %llu not in cache\n", (unsigned long long)sector
);
584 * Need to check if array has failed when deciding whether to:
586 * - remove non-faulty devices
589 * This determination is simple when no reshape is happening.
590 * However if there is a reshape, we need to carefully check
591 * both the before and after sections.
592 * This is because some failed devices may only affect one
593 * of the two sections, and some non-in_sync devices may
594 * be insync in the section most affected by failed devices.
596 static int calc_degraded(struct r5conf
*conf
)
598 int degraded
, degraded2
;
603 for (i
= 0; i
< conf
->previous_raid_disks
; i
++) {
604 struct md_rdev
*rdev
= rcu_dereference(conf
->disks
[i
].rdev
);
605 if (rdev
&& test_bit(Faulty
, &rdev
->flags
))
606 rdev
= rcu_dereference(conf
->disks
[i
].replacement
);
607 if (!rdev
|| test_bit(Faulty
, &rdev
->flags
))
609 else if (test_bit(In_sync
, &rdev
->flags
))
612 /* not in-sync or faulty.
613 * If the reshape increases the number of devices,
614 * this is being recovered by the reshape, so
615 * this 'previous' section is not in_sync.
616 * If the number of devices is being reduced however,
617 * the device can only be part of the array if
618 * we are reverting a reshape, so this section will
621 if (conf
->raid_disks
>= conf
->previous_raid_disks
)
625 if (conf
->raid_disks
== conf
->previous_raid_disks
)
629 for (i
= 0; i
< conf
->raid_disks
; i
++) {
630 struct md_rdev
*rdev
= rcu_dereference(conf
->disks
[i
].rdev
);
631 if (rdev
&& test_bit(Faulty
, &rdev
->flags
))
632 rdev
= rcu_dereference(conf
->disks
[i
].replacement
);
633 if (!rdev
|| test_bit(Faulty
, &rdev
->flags
))
635 else if (test_bit(In_sync
, &rdev
->flags
))
638 /* not in-sync or faulty.
639 * If reshape increases the number of devices, this
640 * section has already been recovered, else it
641 * almost certainly hasn't.
643 if (conf
->raid_disks
<= conf
->previous_raid_disks
)
647 if (degraded2
> degraded
)
652 static int has_failed(struct r5conf
*conf
)
656 if (conf
->mddev
->reshape_position
== MaxSector
)
657 return conf
->mddev
->degraded
> conf
->max_degraded
;
659 degraded
= calc_degraded(conf
);
660 if (degraded
> conf
->max_degraded
)
665 static struct stripe_head
*
666 get_active_stripe(struct r5conf
*conf
, sector_t sector
,
667 int previous
, int noblock
, int noquiesce
)
669 struct stripe_head
*sh
;
670 int hash
= stripe_hash_locks_hash(sector
);
672 pr_debug("get_stripe, sector %llu\n", (unsigned long long)sector
);
674 spin_lock_irq(conf
->hash_locks
+ hash
);
677 wait_event_lock_irq(conf
->wait_for_quiescent
,
678 conf
->quiesce
== 0 || noquiesce
,
679 *(conf
->hash_locks
+ hash
));
680 sh
= __find_stripe(conf
, sector
, conf
->generation
- previous
);
682 if (!test_bit(R5_INACTIVE_BLOCKED
, &conf
->cache_state
)) {
683 sh
= get_free_stripe(conf
, hash
);
684 if (!sh
&& !test_bit(R5_DID_ALLOC
,
686 set_bit(R5_ALLOC_MORE
,
689 if (noblock
&& sh
== NULL
)
692 set_bit(R5_INACTIVE_BLOCKED
,
694 wait_event_exclusive_cmd(
695 conf
->wait_for_stripe
[hash
],
696 !list_empty(conf
->inactive_list
+ hash
) &&
697 (atomic_read(&conf
->active_stripes
)
698 < (conf
->max_nr_stripes
* 3 / 4)
699 || !test_bit(R5_INACTIVE_BLOCKED
,
700 &conf
->cache_state
)),
701 spin_unlock_irq(conf
->hash_locks
+ hash
),
702 spin_lock_irq(conf
->hash_locks
+ hash
));
703 clear_bit(R5_INACTIVE_BLOCKED
,
706 init_stripe(sh
, sector
, previous
);
707 atomic_inc(&sh
->count
);
709 } else if (!atomic_inc_not_zero(&sh
->count
)) {
710 spin_lock(&conf
->device_lock
);
711 if (!atomic_read(&sh
->count
)) {
712 if (!test_bit(STRIPE_HANDLE
, &sh
->state
))
713 atomic_inc(&conf
->active_stripes
);
714 BUG_ON(list_empty(&sh
->lru
) &&
715 !test_bit(STRIPE_EXPANDING
, &sh
->state
));
716 list_del_init(&sh
->lru
);
718 sh
->group
->stripes_cnt
--;
722 atomic_inc(&sh
->count
);
723 spin_unlock(&conf
->device_lock
);
725 } while (sh
== NULL
);
727 if (!list_empty(conf
->inactive_list
+ hash
))
728 wake_up(&conf
->wait_for_stripe
[hash
]);
730 spin_unlock_irq(conf
->hash_locks
+ hash
);
734 static bool is_full_stripe_write(struct stripe_head
*sh
)
736 BUG_ON(sh
->overwrite_disks
> (sh
->disks
- sh
->raid_conf
->max_degraded
));
737 return sh
->overwrite_disks
== (sh
->disks
- sh
->raid_conf
->max_degraded
);
740 static void lock_two_stripes(struct stripe_head
*sh1
, struct stripe_head
*sh2
)
744 spin_lock(&sh2
->stripe_lock
);
745 spin_lock_nested(&sh1
->stripe_lock
, 1);
747 spin_lock(&sh1
->stripe_lock
);
748 spin_lock_nested(&sh2
->stripe_lock
, 1);
752 static void unlock_two_stripes(struct stripe_head
*sh1
, struct stripe_head
*sh2
)
754 spin_unlock(&sh1
->stripe_lock
);
755 spin_unlock(&sh2
->stripe_lock
);
759 /* Only freshly new full stripe normal write stripe can be added to a batch list */
760 static bool stripe_can_batch(struct stripe_head
*sh
)
762 return test_bit(STRIPE_BATCH_READY
, &sh
->state
) &&
763 !test_bit(STRIPE_BITMAP_PENDING
, &sh
->state
) &&
764 is_full_stripe_write(sh
);
767 /* we only do back search */
768 static void stripe_add_to_batch_list(struct r5conf
*conf
, struct stripe_head
*sh
)
770 struct stripe_head
*head
;
771 sector_t head_sector
, tmp_sec
;
775 if (!stripe_can_batch(sh
))
777 /* Don't cross chunks, so stripe pd_idx/qd_idx is the same */
778 tmp_sec
= sh
->sector
;
779 if (!sector_div(tmp_sec
, conf
->chunk_sectors
))
781 head_sector
= sh
->sector
- STRIPE_SECTORS
;
783 hash
= stripe_hash_locks_hash(head_sector
);
784 spin_lock_irq(conf
->hash_locks
+ hash
);
785 head
= __find_stripe(conf
, head_sector
, conf
->generation
);
786 if (head
&& !atomic_inc_not_zero(&head
->count
)) {
787 spin_lock(&conf
->device_lock
);
788 if (!atomic_read(&head
->count
)) {
789 if (!test_bit(STRIPE_HANDLE
, &head
->state
))
790 atomic_inc(&conf
->active_stripes
);
791 BUG_ON(list_empty(&head
->lru
) &&
792 !test_bit(STRIPE_EXPANDING
, &head
->state
));
793 list_del_init(&head
->lru
);
795 head
->group
->stripes_cnt
--;
799 atomic_inc(&head
->count
);
800 spin_unlock(&conf
->device_lock
);
802 spin_unlock_irq(conf
->hash_locks
+ hash
);
806 if (!stripe_can_batch(head
))
809 lock_two_stripes(head
, sh
);
810 /* clear_batch_ready clear the flag */
811 if (!stripe_can_batch(head
) || !stripe_can_batch(sh
))
818 while (dd_idx
== sh
->pd_idx
|| dd_idx
== sh
->qd_idx
)
820 if (head
->dev
[dd_idx
].towrite
->bi_rw
!= sh
->dev
[dd_idx
].towrite
->bi_rw
)
823 if (head
->batch_head
) {
824 spin_lock(&head
->batch_head
->batch_lock
);
825 /* This batch list is already running */
826 if (!stripe_can_batch(head
)) {
827 spin_unlock(&head
->batch_head
->batch_lock
);
832 * at this point, head's BATCH_READY could be cleared, but we
833 * can still add the stripe to batch list
835 list_add(&sh
->batch_list
, &head
->batch_list
);
836 spin_unlock(&head
->batch_head
->batch_lock
);
838 sh
->batch_head
= head
->batch_head
;
840 head
->batch_head
= head
;
841 sh
->batch_head
= head
->batch_head
;
842 spin_lock(&head
->batch_lock
);
843 list_add_tail(&sh
->batch_list
, &head
->batch_list
);
844 spin_unlock(&head
->batch_lock
);
847 if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
848 if (atomic_dec_return(&conf
->preread_active_stripes
)
850 md_wakeup_thread(conf
->mddev
->thread
);
852 if (test_and_clear_bit(STRIPE_BIT_DELAY
, &sh
->state
)) {
853 int seq
= sh
->bm_seq
;
854 if (test_bit(STRIPE_BIT_DELAY
, &sh
->batch_head
->state
) &&
855 sh
->batch_head
->bm_seq
> seq
)
856 seq
= sh
->batch_head
->bm_seq
;
857 set_bit(STRIPE_BIT_DELAY
, &sh
->batch_head
->state
);
858 sh
->batch_head
->bm_seq
= seq
;
861 atomic_inc(&sh
->count
);
863 unlock_two_stripes(head
, sh
);
865 release_stripe(head
);
868 /* Determine if 'data_offset' or 'new_data_offset' should be used
869 * in this stripe_head.
871 static int use_new_offset(struct r5conf
*conf
, struct stripe_head
*sh
)
873 sector_t progress
= conf
->reshape_progress
;
874 /* Need a memory barrier to make sure we see the value
875 * of conf->generation, or ->data_offset that was set before
876 * reshape_progress was updated.
879 if (progress
== MaxSector
)
881 if (sh
->generation
== conf
->generation
- 1)
883 /* We are in a reshape, and this is a new-generation stripe,
884 * so use new_data_offset.
890 raid5_end_read_request(struct bio
*bi
, int error
);
892 raid5_end_write_request(struct bio
*bi
, int error
);
894 static void ops_run_io(struct stripe_head
*sh
, struct stripe_head_state
*s
)
896 struct r5conf
*conf
= sh
->raid_conf
;
897 int i
, disks
= sh
->disks
;
898 struct stripe_head
*head_sh
= sh
;
902 for (i
= disks
; i
--; ) {
904 int replace_only
= 0;
905 struct bio
*bi
, *rbi
;
906 struct md_rdev
*rdev
, *rrdev
= NULL
;
909 if (test_and_clear_bit(R5_Wantwrite
, &sh
->dev
[i
].flags
)) {
910 if (test_and_clear_bit(R5_WantFUA
, &sh
->dev
[i
].flags
))
914 if (test_bit(R5_Discard
, &sh
->dev
[i
].flags
))
916 } else if (test_and_clear_bit(R5_Wantread
, &sh
->dev
[i
].flags
))
918 else if (test_and_clear_bit(R5_WantReplace
,
919 &sh
->dev
[i
].flags
)) {
924 if (test_and_clear_bit(R5_SyncIO
, &sh
->dev
[i
].flags
))
928 bi
= &sh
->dev
[i
].req
;
929 rbi
= &sh
->dev
[i
].rreq
; /* For writing to replacement */
932 rrdev
= rcu_dereference(conf
->disks
[i
].replacement
);
933 smp_mb(); /* Ensure that if rrdev is NULL, rdev won't be */
934 rdev
= rcu_dereference(conf
->disks
[i
].rdev
);
943 /* We raced and saw duplicates */
946 if (test_bit(R5_ReadRepl
, &head_sh
->dev
[i
].flags
) && rrdev
)
951 if (rdev
&& test_bit(Faulty
, &rdev
->flags
))
954 atomic_inc(&rdev
->nr_pending
);
955 if (rrdev
&& test_bit(Faulty
, &rrdev
->flags
))
958 atomic_inc(&rrdev
->nr_pending
);
961 /* We have already checked bad blocks for reads. Now
962 * need to check for writes. We never accept write errors
963 * on the replacement, so we don't to check rrdev.
965 while ((rw
& WRITE
) && rdev
&&
966 test_bit(WriteErrorSeen
, &rdev
->flags
)) {
969 int bad
= is_badblock(rdev
, sh
->sector
, STRIPE_SECTORS
,
970 &first_bad
, &bad_sectors
);
975 set_bit(BlockedBadBlocks
, &rdev
->flags
);
976 if (!conf
->mddev
->external
&&
977 conf
->mddev
->flags
) {
978 /* It is very unlikely, but we might
979 * still need to write out the
980 * bad block log - better give it
982 md_check_recovery(conf
->mddev
);
985 * Because md_wait_for_blocked_rdev
986 * will dec nr_pending, we must
987 * increment it first.
989 atomic_inc(&rdev
->nr_pending
);
990 md_wait_for_blocked_rdev(rdev
, conf
->mddev
);
992 /* Acknowledged bad block - skip the write */
993 rdev_dec_pending(rdev
, conf
->mddev
);
999 if (s
->syncing
|| s
->expanding
|| s
->expanded
1001 md_sync_acct(rdev
->bdev
, STRIPE_SECTORS
);
1003 set_bit(STRIPE_IO_STARTED
, &sh
->state
);
1006 bi
->bi_bdev
= rdev
->bdev
;
1008 bi
->bi_end_io
= (rw
& WRITE
)
1009 ? raid5_end_write_request
1010 : raid5_end_read_request
;
1011 bi
->bi_private
= sh
;
1013 pr_debug("%s: for %llu schedule op %ld on disc %d\n",
1014 __func__
, (unsigned long long)sh
->sector
,
1016 atomic_inc(&sh
->count
);
1018 atomic_inc(&head_sh
->count
);
1019 if (use_new_offset(conf
, sh
))
1020 bi
->bi_iter
.bi_sector
= (sh
->sector
1021 + rdev
->new_data_offset
);
1023 bi
->bi_iter
.bi_sector
= (sh
->sector
1024 + rdev
->data_offset
);
1025 if (test_bit(R5_ReadNoMerge
, &head_sh
->dev
[i
].flags
))
1026 bi
->bi_rw
|= REQ_NOMERGE
;
1028 if (test_bit(R5_SkipCopy
, &sh
->dev
[i
].flags
))
1029 WARN_ON(test_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
));
1030 sh
->dev
[i
].vec
.bv_page
= sh
->dev
[i
].page
;
1032 bi
->bi_io_vec
[0].bv_len
= STRIPE_SIZE
;
1033 bi
->bi_io_vec
[0].bv_offset
= 0;
1034 bi
->bi_iter
.bi_size
= STRIPE_SIZE
;
1036 * If this is discard request, set bi_vcnt 0. We don't
1037 * want to confuse SCSI because SCSI will replace payload
1039 if (rw
& REQ_DISCARD
)
1042 set_bit(R5_DOUBLE_LOCKED
, &sh
->dev
[i
].flags
);
1044 if (conf
->mddev
->gendisk
)
1045 trace_block_bio_remap(bdev_get_queue(bi
->bi_bdev
),
1046 bi
, disk_devt(conf
->mddev
->gendisk
),
1048 generic_make_request(bi
);
1051 if (s
->syncing
|| s
->expanding
|| s
->expanded
1053 md_sync_acct(rrdev
->bdev
, STRIPE_SECTORS
);
1055 set_bit(STRIPE_IO_STARTED
, &sh
->state
);
1058 rbi
->bi_bdev
= rrdev
->bdev
;
1060 BUG_ON(!(rw
& WRITE
));
1061 rbi
->bi_end_io
= raid5_end_write_request
;
1062 rbi
->bi_private
= sh
;
1064 pr_debug("%s: for %llu schedule op %ld on "
1065 "replacement disc %d\n",
1066 __func__
, (unsigned long long)sh
->sector
,
1068 atomic_inc(&sh
->count
);
1070 atomic_inc(&head_sh
->count
);
1071 if (use_new_offset(conf
, sh
))
1072 rbi
->bi_iter
.bi_sector
= (sh
->sector
1073 + rrdev
->new_data_offset
);
1075 rbi
->bi_iter
.bi_sector
= (sh
->sector
1076 + rrdev
->data_offset
);
1077 if (test_bit(R5_SkipCopy
, &sh
->dev
[i
].flags
))
1078 WARN_ON(test_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
));
1079 sh
->dev
[i
].rvec
.bv_page
= sh
->dev
[i
].page
;
1081 rbi
->bi_io_vec
[0].bv_len
= STRIPE_SIZE
;
1082 rbi
->bi_io_vec
[0].bv_offset
= 0;
1083 rbi
->bi_iter
.bi_size
= STRIPE_SIZE
;
1085 * If this is discard request, set bi_vcnt 0. We don't
1086 * want to confuse SCSI because SCSI will replace payload
1088 if (rw
& REQ_DISCARD
)
1090 if (conf
->mddev
->gendisk
)
1091 trace_block_bio_remap(bdev_get_queue(rbi
->bi_bdev
),
1092 rbi
, disk_devt(conf
->mddev
->gendisk
),
1094 generic_make_request(rbi
);
1096 if (!rdev
&& !rrdev
) {
1098 set_bit(STRIPE_DEGRADED
, &sh
->state
);
1099 pr_debug("skip op %ld on disc %d for sector %llu\n",
1100 bi
->bi_rw
, i
, (unsigned long long)sh
->sector
);
1101 clear_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
1102 set_bit(STRIPE_HANDLE
, &sh
->state
);
1105 if (!head_sh
->batch_head
)
1107 sh
= list_first_entry(&sh
->batch_list
, struct stripe_head
,
1114 static struct dma_async_tx_descriptor
*
1115 async_copy_data(int frombio
, struct bio
*bio
, struct page
**page
,
1116 sector_t sector
, struct dma_async_tx_descriptor
*tx
,
1117 struct stripe_head
*sh
)
1120 struct bvec_iter iter
;
1121 struct page
*bio_page
;
1123 struct async_submit_ctl submit
;
1124 enum async_tx_flags flags
= 0;
1126 if (bio
->bi_iter
.bi_sector
>= sector
)
1127 page_offset
= (signed)(bio
->bi_iter
.bi_sector
- sector
) * 512;
1129 page_offset
= (signed)(sector
- bio
->bi_iter
.bi_sector
) * -512;
1132 flags
|= ASYNC_TX_FENCE
;
1133 init_async_submit(&submit
, flags
, tx
, NULL
, NULL
, NULL
);
1135 bio_for_each_segment(bvl
, bio
, iter
) {
1136 int len
= bvl
.bv_len
;
1140 if (page_offset
< 0) {
1141 b_offset
= -page_offset
;
1142 page_offset
+= b_offset
;
1146 if (len
> 0 && page_offset
+ len
> STRIPE_SIZE
)
1147 clen
= STRIPE_SIZE
- page_offset
;
1152 b_offset
+= bvl
.bv_offset
;
1153 bio_page
= bvl
.bv_page
;
1155 if (sh
->raid_conf
->skip_copy
&&
1156 b_offset
== 0 && page_offset
== 0 &&
1157 clen
== STRIPE_SIZE
)
1160 tx
= async_memcpy(*page
, bio_page
, page_offset
,
1161 b_offset
, clen
, &submit
);
1163 tx
= async_memcpy(bio_page
, *page
, b_offset
,
1164 page_offset
, clen
, &submit
);
1166 /* chain the operations */
1167 submit
.depend_tx
= tx
;
1169 if (clen
< len
) /* hit end of page */
1177 static void ops_complete_biofill(void *stripe_head_ref
)
1179 struct stripe_head
*sh
= stripe_head_ref
;
1180 struct bio
*return_bi
= NULL
;
1183 pr_debug("%s: stripe %llu\n", __func__
,
1184 (unsigned long long)sh
->sector
);
1186 /* clear completed biofills */
1187 for (i
= sh
->disks
; i
--; ) {
1188 struct r5dev
*dev
= &sh
->dev
[i
];
1190 /* acknowledge completion of a biofill operation */
1191 /* and check if we need to reply to a read request,
1192 * new R5_Wantfill requests are held off until
1193 * !STRIPE_BIOFILL_RUN
1195 if (test_and_clear_bit(R5_Wantfill
, &dev
->flags
)) {
1196 struct bio
*rbi
, *rbi2
;
1201 while (rbi
&& rbi
->bi_iter
.bi_sector
<
1202 dev
->sector
+ STRIPE_SECTORS
) {
1203 rbi2
= r5_next_bio(rbi
, dev
->sector
);
1204 if (!raid5_dec_bi_active_stripes(rbi
)) {
1205 rbi
->bi_next
= return_bi
;
1212 clear_bit(STRIPE_BIOFILL_RUN
, &sh
->state
);
1214 return_io(return_bi
);
1216 set_bit(STRIPE_HANDLE
, &sh
->state
);
1220 static void ops_run_biofill(struct stripe_head
*sh
)
1222 struct dma_async_tx_descriptor
*tx
= NULL
;
1223 struct async_submit_ctl submit
;
1226 BUG_ON(sh
->batch_head
);
1227 pr_debug("%s: stripe %llu\n", __func__
,
1228 (unsigned long long)sh
->sector
);
1230 for (i
= sh
->disks
; i
--; ) {
1231 struct r5dev
*dev
= &sh
->dev
[i
];
1232 if (test_bit(R5_Wantfill
, &dev
->flags
)) {
1234 spin_lock_irq(&sh
->stripe_lock
);
1235 dev
->read
= rbi
= dev
->toread
;
1237 spin_unlock_irq(&sh
->stripe_lock
);
1238 while (rbi
&& rbi
->bi_iter
.bi_sector
<
1239 dev
->sector
+ STRIPE_SECTORS
) {
1240 tx
= async_copy_data(0, rbi
, &dev
->page
,
1241 dev
->sector
, tx
, sh
);
1242 rbi
= r5_next_bio(rbi
, dev
->sector
);
1247 atomic_inc(&sh
->count
);
1248 init_async_submit(&submit
, ASYNC_TX_ACK
, tx
, ops_complete_biofill
, sh
, NULL
);
1249 async_trigger_callback(&submit
);
1252 static void mark_target_uptodate(struct stripe_head
*sh
, int target
)
1259 tgt
= &sh
->dev
[target
];
1260 set_bit(R5_UPTODATE
, &tgt
->flags
);
1261 BUG_ON(!test_bit(R5_Wantcompute
, &tgt
->flags
));
1262 clear_bit(R5_Wantcompute
, &tgt
->flags
);
1265 static void ops_complete_compute(void *stripe_head_ref
)
1267 struct stripe_head
*sh
= stripe_head_ref
;
1269 pr_debug("%s: stripe %llu\n", __func__
,
1270 (unsigned long long)sh
->sector
);
1272 /* mark the computed target(s) as uptodate */
1273 mark_target_uptodate(sh
, sh
->ops
.target
);
1274 mark_target_uptodate(sh
, sh
->ops
.target2
);
1276 clear_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
1277 if (sh
->check_state
== check_state_compute_run
)
1278 sh
->check_state
= check_state_compute_result
;
1279 set_bit(STRIPE_HANDLE
, &sh
->state
);
1283 /* return a pointer to the address conversion region of the scribble buffer */
1284 static addr_conv_t
*to_addr_conv(struct stripe_head
*sh
,
1285 struct raid5_percpu
*percpu
, int i
)
1289 addr
= flex_array_get(percpu
->scribble
, i
);
1290 return addr
+ sizeof(struct page
*) * (sh
->disks
+ 2);
1293 /* return a pointer to the address conversion region of the scribble buffer */
1294 static struct page
**to_addr_page(struct raid5_percpu
*percpu
, int i
)
1298 addr
= flex_array_get(percpu
->scribble
, i
);
1302 static struct dma_async_tx_descriptor
*
1303 ops_run_compute5(struct stripe_head
*sh
, struct raid5_percpu
*percpu
)
1305 int disks
= sh
->disks
;
1306 struct page
**xor_srcs
= to_addr_page(percpu
, 0);
1307 int target
= sh
->ops
.target
;
1308 struct r5dev
*tgt
= &sh
->dev
[target
];
1309 struct page
*xor_dest
= tgt
->page
;
1311 struct dma_async_tx_descriptor
*tx
;
1312 struct async_submit_ctl submit
;
1315 BUG_ON(sh
->batch_head
);
1317 pr_debug("%s: stripe %llu block: %d\n",
1318 __func__
, (unsigned long long)sh
->sector
, target
);
1319 BUG_ON(!test_bit(R5_Wantcompute
, &tgt
->flags
));
1321 for (i
= disks
; i
--; )
1323 xor_srcs
[count
++] = sh
->dev
[i
].page
;
1325 atomic_inc(&sh
->count
);
1327 init_async_submit(&submit
, ASYNC_TX_FENCE
|ASYNC_TX_XOR_ZERO_DST
, NULL
,
1328 ops_complete_compute
, sh
, to_addr_conv(sh
, percpu
, 0));
1329 if (unlikely(count
== 1))
1330 tx
= async_memcpy(xor_dest
, xor_srcs
[0], 0, 0, STRIPE_SIZE
, &submit
);
1332 tx
= async_xor(xor_dest
, xor_srcs
, 0, count
, STRIPE_SIZE
, &submit
);
1337 /* set_syndrome_sources - populate source buffers for gen_syndrome
1338 * @srcs - (struct page *) array of size sh->disks
1339 * @sh - stripe_head to parse
1341 * Populates srcs in proper layout order for the stripe and returns the
1342 * 'count' of sources to be used in a call to async_gen_syndrome. The P
1343 * destination buffer is recorded in srcs[count] and the Q destination
1344 * is recorded in srcs[count+1]].
1346 static int set_syndrome_sources(struct page
**srcs
,
1347 struct stripe_head
*sh
,
1350 int disks
= sh
->disks
;
1351 int syndrome_disks
= sh
->ddf_layout
? disks
: (disks
- 2);
1352 int d0_idx
= raid6_d0(sh
);
1356 for (i
= 0; i
< disks
; i
++)
1362 int slot
= raid6_idx_to_slot(i
, sh
, &count
, syndrome_disks
);
1363 struct r5dev
*dev
= &sh
->dev
[i
];
1365 if (i
== sh
->qd_idx
|| i
== sh
->pd_idx
||
1366 (srctype
== SYNDROME_SRC_ALL
) ||
1367 (srctype
== SYNDROME_SRC_WANT_DRAIN
&&
1368 test_bit(R5_Wantdrain
, &dev
->flags
)) ||
1369 (srctype
== SYNDROME_SRC_WRITTEN
&&
1371 srcs
[slot
] = sh
->dev
[i
].page
;
1372 i
= raid6_next_disk(i
, disks
);
1373 } while (i
!= d0_idx
);
1375 return syndrome_disks
;
1378 static struct dma_async_tx_descriptor
*
1379 ops_run_compute6_1(struct stripe_head
*sh
, struct raid5_percpu
*percpu
)
1381 int disks
= sh
->disks
;
1382 struct page
**blocks
= to_addr_page(percpu
, 0);
1384 int qd_idx
= sh
->qd_idx
;
1385 struct dma_async_tx_descriptor
*tx
;
1386 struct async_submit_ctl submit
;
1392 BUG_ON(sh
->batch_head
);
1393 if (sh
->ops
.target
< 0)
1394 target
= sh
->ops
.target2
;
1395 else if (sh
->ops
.target2
< 0)
1396 target
= sh
->ops
.target
;
1398 /* we should only have one valid target */
1401 pr_debug("%s: stripe %llu block: %d\n",
1402 __func__
, (unsigned long long)sh
->sector
, target
);
1404 tgt
= &sh
->dev
[target
];
1405 BUG_ON(!test_bit(R5_Wantcompute
, &tgt
->flags
));
1408 atomic_inc(&sh
->count
);
1410 if (target
== qd_idx
) {
1411 count
= set_syndrome_sources(blocks
, sh
, SYNDROME_SRC_ALL
);
1412 blocks
[count
] = NULL
; /* regenerating p is not necessary */
1413 BUG_ON(blocks
[count
+1] != dest
); /* q should already be set */
1414 init_async_submit(&submit
, ASYNC_TX_FENCE
, NULL
,
1415 ops_complete_compute
, sh
,
1416 to_addr_conv(sh
, percpu
, 0));
1417 tx
= async_gen_syndrome(blocks
, 0, count
+2, STRIPE_SIZE
, &submit
);
1419 /* Compute any data- or p-drive using XOR */
1421 for (i
= disks
; i
-- ; ) {
1422 if (i
== target
|| i
== qd_idx
)
1424 blocks
[count
++] = sh
->dev
[i
].page
;
1427 init_async_submit(&submit
, ASYNC_TX_FENCE
|ASYNC_TX_XOR_ZERO_DST
,
1428 NULL
, ops_complete_compute
, sh
,
1429 to_addr_conv(sh
, percpu
, 0));
1430 tx
= async_xor(dest
, blocks
, 0, count
, STRIPE_SIZE
, &submit
);
1436 static struct dma_async_tx_descriptor
*
1437 ops_run_compute6_2(struct stripe_head
*sh
, struct raid5_percpu
*percpu
)
1439 int i
, count
, disks
= sh
->disks
;
1440 int syndrome_disks
= sh
->ddf_layout
? disks
: disks
-2;
1441 int d0_idx
= raid6_d0(sh
);
1442 int faila
= -1, failb
= -1;
1443 int target
= sh
->ops
.target
;
1444 int target2
= sh
->ops
.target2
;
1445 struct r5dev
*tgt
= &sh
->dev
[target
];
1446 struct r5dev
*tgt2
= &sh
->dev
[target2
];
1447 struct dma_async_tx_descriptor
*tx
;
1448 struct page
**blocks
= to_addr_page(percpu
, 0);
1449 struct async_submit_ctl submit
;
1451 BUG_ON(sh
->batch_head
);
1452 pr_debug("%s: stripe %llu block1: %d block2: %d\n",
1453 __func__
, (unsigned long long)sh
->sector
, target
, target2
);
1454 BUG_ON(target
< 0 || target2
< 0);
1455 BUG_ON(!test_bit(R5_Wantcompute
, &tgt
->flags
));
1456 BUG_ON(!test_bit(R5_Wantcompute
, &tgt2
->flags
));
1458 /* we need to open-code set_syndrome_sources to handle the
1459 * slot number conversion for 'faila' and 'failb'
1461 for (i
= 0; i
< disks
; i
++)
1466 int slot
= raid6_idx_to_slot(i
, sh
, &count
, syndrome_disks
);
1468 blocks
[slot
] = sh
->dev
[i
].page
;
1474 i
= raid6_next_disk(i
, disks
);
1475 } while (i
!= d0_idx
);
1477 BUG_ON(faila
== failb
);
1480 pr_debug("%s: stripe: %llu faila: %d failb: %d\n",
1481 __func__
, (unsigned long long)sh
->sector
, faila
, failb
);
1483 atomic_inc(&sh
->count
);
1485 if (failb
== syndrome_disks
+1) {
1486 /* Q disk is one of the missing disks */
1487 if (faila
== syndrome_disks
) {
1488 /* Missing P+Q, just recompute */
1489 init_async_submit(&submit
, ASYNC_TX_FENCE
, NULL
,
1490 ops_complete_compute
, sh
,
1491 to_addr_conv(sh
, percpu
, 0));
1492 return async_gen_syndrome(blocks
, 0, syndrome_disks
+2,
1493 STRIPE_SIZE
, &submit
);
1497 int qd_idx
= sh
->qd_idx
;
1499 /* Missing D+Q: recompute D from P, then recompute Q */
1500 if (target
== qd_idx
)
1501 data_target
= target2
;
1503 data_target
= target
;
1506 for (i
= disks
; i
-- ; ) {
1507 if (i
== data_target
|| i
== qd_idx
)
1509 blocks
[count
++] = sh
->dev
[i
].page
;
1511 dest
= sh
->dev
[data_target
].page
;
1512 init_async_submit(&submit
,
1513 ASYNC_TX_FENCE
|ASYNC_TX_XOR_ZERO_DST
,
1515 to_addr_conv(sh
, percpu
, 0));
1516 tx
= async_xor(dest
, blocks
, 0, count
, STRIPE_SIZE
,
1519 count
= set_syndrome_sources(blocks
, sh
, SYNDROME_SRC_ALL
);
1520 init_async_submit(&submit
, ASYNC_TX_FENCE
, tx
,
1521 ops_complete_compute
, sh
,
1522 to_addr_conv(sh
, percpu
, 0));
1523 return async_gen_syndrome(blocks
, 0, count
+2,
1524 STRIPE_SIZE
, &submit
);
1527 init_async_submit(&submit
, ASYNC_TX_FENCE
, NULL
,
1528 ops_complete_compute
, sh
,
1529 to_addr_conv(sh
, percpu
, 0));
1530 if (failb
== syndrome_disks
) {
1531 /* We're missing D+P. */
1532 return async_raid6_datap_recov(syndrome_disks
+2,
1536 /* We're missing D+D. */
1537 return async_raid6_2data_recov(syndrome_disks
+2,
1538 STRIPE_SIZE
, faila
, failb
,
1544 static void ops_complete_prexor(void *stripe_head_ref
)
1546 struct stripe_head
*sh
= stripe_head_ref
;
1548 pr_debug("%s: stripe %llu\n", __func__
,
1549 (unsigned long long)sh
->sector
);
1552 static struct dma_async_tx_descriptor
*
1553 ops_run_prexor5(struct stripe_head
*sh
, struct raid5_percpu
*percpu
,
1554 struct dma_async_tx_descriptor
*tx
)
1556 int disks
= sh
->disks
;
1557 struct page
**xor_srcs
= to_addr_page(percpu
, 0);
1558 int count
= 0, pd_idx
= sh
->pd_idx
, i
;
1559 struct async_submit_ctl submit
;
1561 /* existing parity data subtracted */
1562 struct page
*xor_dest
= xor_srcs
[count
++] = sh
->dev
[pd_idx
].page
;
1564 BUG_ON(sh
->batch_head
);
1565 pr_debug("%s: stripe %llu\n", __func__
,
1566 (unsigned long long)sh
->sector
);
1568 for (i
= disks
; i
--; ) {
1569 struct r5dev
*dev
= &sh
->dev
[i
];
1570 /* Only process blocks that are known to be uptodate */
1571 if (test_bit(R5_Wantdrain
, &dev
->flags
))
1572 xor_srcs
[count
++] = dev
->page
;
1575 init_async_submit(&submit
, ASYNC_TX_FENCE
|ASYNC_TX_XOR_DROP_DST
, tx
,
1576 ops_complete_prexor
, sh
, to_addr_conv(sh
, percpu
, 0));
1577 tx
= async_xor(xor_dest
, xor_srcs
, 0, count
, STRIPE_SIZE
, &submit
);
1582 static struct dma_async_tx_descriptor
*
1583 ops_run_prexor6(struct stripe_head
*sh
, struct raid5_percpu
*percpu
,
1584 struct dma_async_tx_descriptor
*tx
)
1586 struct page
**blocks
= to_addr_page(percpu
, 0);
1588 struct async_submit_ctl submit
;
1590 pr_debug("%s: stripe %llu\n", __func__
,
1591 (unsigned long long)sh
->sector
);
1593 count
= set_syndrome_sources(blocks
, sh
, SYNDROME_SRC_WANT_DRAIN
);
1595 init_async_submit(&submit
, ASYNC_TX_FENCE
|ASYNC_TX_PQ_XOR_DST
, tx
,
1596 ops_complete_prexor
, sh
, to_addr_conv(sh
, percpu
, 0));
1597 tx
= async_gen_syndrome(blocks
, 0, count
+2, STRIPE_SIZE
, &submit
);
1602 static struct dma_async_tx_descriptor
*
1603 ops_run_biodrain(struct stripe_head
*sh
, struct dma_async_tx_descriptor
*tx
)
1605 int disks
= sh
->disks
;
1607 struct stripe_head
*head_sh
= sh
;
1609 pr_debug("%s: stripe %llu\n", __func__
,
1610 (unsigned long long)sh
->sector
);
1612 for (i
= disks
; i
--; ) {
1617 if (test_and_clear_bit(R5_Wantdrain
, &head_sh
->dev
[i
].flags
)) {
1622 spin_lock_irq(&sh
->stripe_lock
);
1623 chosen
= dev
->towrite
;
1624 dev
->towrite
= NULL
;
1625 sh
->overwrite_disks
= 0;
1626 BUG_ON(dev
->written
);
1627 wbi
= dev
->written
= chosen
;
1628 spin_unlock_irq(&sh
->stripe_lock
);
1629 WARN_ON(dev
->page
!= dev
->orig_page
);
1631 while (wbi
&& wbi
->bi_iter
.bi_sector
<
1632 dev
->sector
+ STRIPE_SECTORS
) {
1633 if (wbi
->bi_rw
& REQ_FUA
)
1634 set_bit(R5_WantFUA
, &dev
->flags
);
1635 if (wbi
->bi_rw
& REQ_SYNC
)
1636 set_bit(R5_SyncIO
, &dev
->flags
);
1637 if (wbi
->bi_rw
& REQ_DISCARD
)
1638 set_bit(R5_Discard
, &dev
->flags
);
1640 tx
= async_copy_data(1, wbi
, &dev
->page
,
1641 dev
->sector
, tx
, sh
);
1642 if (dev
->page
!= dev
->orig_page
) {
1643 set_bit(R5_SkipCopy
, &dev
->flags
);
1644 clear_bit(R5_UPTODATE
, &dev
->flags
);
1645 clear_bit(R5_OVERWRITE
, &dev
->flags
);
1648 wbi
= r5_next_bio(wbi
, dev
->sector
);
1651 if (head_sh
->batch_head
) {
1652 sh
= list_first_entry(&sh
->batch_list
,
1665 static void ops_complete_reconstruct(void *stripe_head_ref
)
1667 struct stripe_head
*sh
= stripe_head_ref
;
1668 int disks
= sh
->disks
;
1669 int pd_idx
= sh
->pd_idx
;
1670 int qd_idx
= sh
->qd_idx
;
1672 bool fua
= false, sync
= false, discard
= false;
1674 pr_debug("%s: stripe %llu\n", __func__
,
1675 (unsigned long long)sh
->sector
);
1677 for (i
= disks
; i
--; ) {
1678 fua
|= test_bit(R5_WantFUA
, &sh
->dev
[i
].flags
);
1679 sync
|= test_bit(R5_SyncIO
, &sh
->dev
[i
].flags
);
1680 discard
|= test_bit(R5_Discard
, &sh
->dev
[i
].flags
);
1683 for (i
= disks
; i
--; ) {
1684 struct r5dev
*dev
= &sh
->dev
[i
];
1686 if (dev
->written
|| i
== pd_idx
|| i
== qd_idx
) {
1687 if (!discard
&& !test_bit(R5_SkipCopy
, &dev
->flags
))
1688 set_bit(R5_UPTODATE
, &dev
->flags
);
1690 set_bit(R5_WantFUA
, &dev
->flags
);
1692 set_bit(R5_SyncIO
, &dev
->flags
);
1696 if (sh
->reconstruct_state
== reconstruct_state_drain_run
)
1697 sh
->reconstruct_state
= reconstruct_state_drain_result
;
1698 else if (sh
->reconstruct_state
== reconstruct_state_prexor_drain_run
)
1699 sh
->reconstruct_state
= reconstruct_state_prexor_drain_result
;
1701 BUG_ON(sh
->reconstruct_state
!= reconstruct_state_run
);
1702 sh
->reconstruct_state
= reconstruct_state_result
;
1705 set_bit(STRIPE_HANDLE
, &sh
->state
);
1710 ops_run_reconstruct5(struct stripe_head
*sh
, struct raid5_percpu
*percpu
,
1711 struct dma_async_tx_descriptor
*tx
)
1713 int disks
= sh
->disks
;
1714 struct page
**xor_srcs
;
1715 struct async_submit_ctl submit
;
1716 int count
, pd_idx
= sh
->pd_idx
, i
;
1717 struct page
*xor_dest
;
1719 unsigned long flags
;
1721 struct stripe_head
*head_sh
= sh
;
1724 pr_debug("%s: stripe %llu\n", __func__
,
1725 (unsigned long long)sh
->sector
);
1727 for (i
= 0; i
< sh
->disks
; i
++) {
1730 if (!test_bit(R5_Discard
, &sh
->dev
[i
].flags
))
1733 if (i
>= sh
->disks
) {
1734 atomic_inc(&sh
->count
);
1735 set_bit(R5_Discard
, &sh
->dev
[pd_idx
].flags
);
1736 ops_complete_reconstruct(sh
);
1741 xor_srcs
= to_addr_page(percpu
, j
);
1742 /* check if prexor is active which means only process blocks
1743 * that are part of a read-modify-write (written)
1745 if (head_sh
->reconstruct_state
== reconstruct_state_prexor_drain_run
) {
1747 xor_dest
= xor_srcs
[count
++] = sh
->dev
[pd_idx
].page
;
1748 for (i
= disks
; i
--; ) {
1749 struct r5dev
*dev
= &sh
->dev
[i
];
1750 if (head_sh
->dev
[i
].written
)
1751 xor_srcs
[count
++] = dev
->page
;
1754 xor_dest
= sh
->dev
[pd_idx
].page
;
1755 for (i
= disks
; i
--; ) {
1756 struct r5dev
*dev
= &sh
->dev
[i
];
1758 xor_srcs
[count
++] = dev
->page
;
1762 /* 1/ if we prexor'd then the dest is reused as a source
1763 * 2/ if we did not prexor then we are redoing the parity
1764 * set ASYNC_TX_XOR_DROP_DST and ASYNC_TX_XOR_ZERO_DST
1765 * for the synchronous xor case
1767 last_stripe
= !head_sh
->batch_head
||
1768 list_first_entry(&sh
->batch_list
,
1769 struct stripe_head
, batch_list
) == head_sh
;
1771 flags
= ASYNC_TX_ACK
|
1772 (prexor
? ASYNC_TX_XOR_DROP_DST
: ASYNC_TX_XOR_ZERO_DST
);
1774 atomic_inc(&head_sh
->count
);
1775 init_async_submit(&submit
, flags
, tx
, ops_complete_reconstruct
, head_sh
,
1776 to_addr_conv(sh
, percpu
, j
));
1778 flags
= prexor
? ASYNC_TX_XOR_DROP_DST
: ASYNC_TX_XOR_ZERO_DST
;
1779 init_async_submit(&submit
, flags
, tx
, NULL
, NULL
,
1780 to_addr_conv(sh
, percpu
, j
));
1783 if (unlikely(count
== 1))
1784 tx
= async_memcpy(xor_dest
, xor_srcs
[0], 0, 0, STRIPE_SIZE
, &submit
);
1786 tx
= async_xor(xor_dest
, xor_srcs
, 0, count
, STRIPE_SIZE
, &submit
);
1789 sh
= list_first_entry(&sh
->batch_list
, struct stripe_head
,
1796 ops_run_reconstruct6(struct stripe_head
*sh
, struct raid5_percpu
*percpu
,
1797 struct dma_async_tx_descriptor
*tx
)
1799 struct async_submit_ctl submit
;
1800 struct page
**blocks
;
1801 int count
, i
, j
= 0;
1802 struct stripe_head
*head_sh
= sh
;
1805 unsigned long txflags
;
1807 pr_debug("%s: stripe %llu\n", __func__
, (unsigned long long)sh
->sector
);
1809 for (i
= 0; i
< sh
->disks
; i
++) {
1810 if (sh
->pd_idx
== i
|| sh
->qd_idx
== i
)
1812 if (!test_bit(R5_Discard
, &sh
->dev
[i
].flags
))
1815 if (i
>= sh
->disks
) {
1816 atomic_inc(&sh
->count
);
1817 set_bit(R5_Discard
, &sh
->dev
[sh
->pd_idx
].flags
);
1818 set_bit(R5_Discard
, &sh
->dev
[sh
->qd_idx
].flags
);
1819 ops_complete_reconstruct(sh
);
1824 blocks
= to_addr_page(percpu
, j
);
1826 if (sh
->reconstruct_state
== reconstruct_state_prexor_drain_run
) {
1827 synflags
= SYNDROME_SRC_WRITTEN
;
1828 txflags
= ASYNC_TX_ACK
| ASYNC_TX_PQ_XOR_DST
;
1830 synflags
= SYNDROME_SRC_ALL
;
1831 txflags
= ASYNC_TX_ACK
;
1834 count
= set_syndrome_sources(blocks
, sh
, synflags
);
1835 last_stripe
= !head_sh
->batch_head
||
1836 list_first_entry(&sh
->batch_list
,
1837 struct stripe_head
, batch_list
) == head_sh
;
1840 atomic_inc(&head_sh
->count
);
1841 init_async_submit(&submit
, txflags
, tx
, ops_complete_reconstruct
,
1842 head_sh
, to_addr_conv(sh
, percpu
, j
));
1844 init_async_submit(&submit
, 0, tx
, NULL
, NULL
,
1845 to_addr_conv(sh
, percpu
, j
));
1846 tx
= async_gen_syndrome(blocks
, 0, count
+2, STRIPE_SIZE
, &submit
);
1849 sh
= list_first_entry(&sh
->batch_list
, struct stripe_head
,
1855 static void ops_complete_check(void *stripe_head_ref
)
1857 struct stripe_head
*sh
= stripe_head_ref
;
1859 pr_debug("%s: stripe %llu\n", __func__
,
1860 (unsigned long long)sh
->sector
);
1862 sh
->check_state
= check_state_check_result
;
1863 set_bit(STRIPE_HANDLE
, &sh
->state
);
1867 static void ops_run_check_p(struct stripe_head
*sh
, struct raid5_percpu
*percpu
)
1869 int disks
= sh
->disks
;
1870 int pd_idx
= sh
->pd_idx
;
1871 int qd_idx
= sh
->qd_idx
;
1872 struct page
*xor_dest
;
1873 struct page
**xor_srcs
= to_addr_page(percpu
, 0);
1874 struct dma_async_tx_descriptor
*tx
;
1875 struct async_submit_ctl submit
;
1879 pr_debug("%s: stripe %llu\n", __func__
,
1880 (unsigned long long)sh
->sector
);
1882 BUG_ON(sh
->batch_head
);
1884 xor_dest
= sh
->dev
[pd_idx
].page
;
1885 xor_srcs
[count
++] = xor_dest
;
1886 for (i
= disks
; i
--; ) {
1887 if (i
== pd_idx
|| i
== qd_idx
)
1889 xor_srcs
[count
++] = sh
->dev
[i
].page
;
1892 init_async_submit(&submit
, 0, NULL
, NULL
, NULL
,
1893 to_addr_conv(sh
, percpu
, 0));
1894 tx
= async_xor_val(xor_dest
, xor_srcs
, 0, count
, STRIPE_SIZE
,
1895 &sh
->ops
.zero_sum_result
, &submit
);
1897 atomic_inc(&sh
->count
);
1898 init_async_submit(&submit
, ASYNC_TX_ACK
, tx
, ops_complete_check
, sh
, NULL
);
1899 tx
= async_trigger_callback(&submit
);
1902 static void ops_run_check_pq(struct stripe_head
*sh
, struct raid5_percpu
*percpu
, int checkp
)
1904 struct page
**srcs
= to_addr_page(percpu
, 0);
1905 struct async_submit_ctl submit
;
1908 pr_debug("%s: stripe %llu checkp: %d\n", __func__
,
1909 (unsigned long long)sh
->sector
, checkp
);
1911 BUG_ON(sh
->batch_head
);
1912 count
= set_syndrome_sources(srcs
, sh
, SYNDROME_SRC_ALL
);
1916 atomic_inc(&sh
->count
);
1917 init_async_submit(&submit
, ASYNC_TX_ACK
, NULL
, ops_complete_check
,
1918 sh
, to_addr_conv(sh
, percpu
, 0));
1919 async_syndrome_val(srcs
, 0, count
+2, STRIPE_SIZE
,
1920 &sh
->ops
.zero_sum_result
, percpu
->spare_page
, &submit
);
1923 static void raid_run_ops(struct stripe_head
*sh
, unsigned long ops_request
)
1925 int overlap_clear
= 0, i
, disks
= sh
->disks
;
1926 struct dma_async_tx_descriptor
*tx
= NULL
;
1927 struct r5conf
*conf
= sh
->raid_conf
;
1928 int level
= conf
->level
;
1929 struct raid5_percpu
*percpu
;
1933 percpu
= per_cpu_ptr(conf
->percpu
, cpu
);
1934 if (test_bit(STRIPE_OP_BIOFILL
, &ops_request
)) {
1935 ops_run_biofill(sh
);
1939 if (test_bit(STRIPE_OP_COMPUTE_BLK
, &ops_request
)) {
1941 tx
= ops_run_compute5(sh
, percpu
);
1943 if (sh
->ops
.target2
< 0 || sh
->ops
.target
< 0)
1944 tx
= ops_run_compute6_1(sh
, percpu
);
1946 tx
= ops_run_compute6_2(sh
, percpu
);
1948 /* terminate the chain if reconstruct is not set to be run */
1949 if (tx
&& !test_bit(STRIPE_OP_RECONSTRUCT
, &ops_request
))
1953 if (test_bit(STRIPE_OP_PREXOR
, &ops_request
)) {
1955 tx
= ops_run_prexor5(sh
, percpu
, tx
);
1957 tx
= ops_run_prexor6(sh
, percpu
, tx
);
1960 if (test_bit(STRIPE_OP_BIODRAIN
, &ops_request
)) {
1961 tx
= ops_run_biodrain(sh
, tx
);
1965 if (test_bit(STRIPE_OP_RECONSTRUCT
, &ops_request
)) {
1967 ops_run_reconstruct5(sh
, percpu
, tx
);
1969 ops_run_reconstruct6(sh
, percpu
, tx
);
1972 if (test_bit(STRIPE_OP_CHECK
, &ops_request
)) {
1973 if (sh
->check_state
== check_state_run
)
1974 ops_run_check_p(sh
, percpu
);
1975 else if (sh
->check_state
== check_state_run_q
)
1976 ops_run_check_pq(sh
, percpu
, 0);
1977 else if (sh
->check_state
== check_state_run_pq
)
1978 ops_run_check_pq(sh
, percpu
, 1);
1983 if (overlap_clear
&& !sh
->batch_head
)
1984 for (i
= disks
; i
--; ) {
1985 struct r5dev
*dev
= &sh
->dev
[i
];
1986 if (test_and_clear_bit(R5_Overlap
, &dev
->flags
))
1987 wake_up(&sh
->raid_conf
->wait_for_overlap
);
1992 static struct stripe_head
*alloc_stripe(struct kmem_cache
*sc
, gfp_t gfp
)
1994 struct stripe_head
*sh
;
1996 sh
= kmem_cache_zalloc(sc
, gfp
);
1998 spin_lock_init(&sh
->stripe_lock
);
1999 spin_lock_init(&sh
->batch_lock
);
2000 INIT_LIST_HEAD(&sh
->batch_list
);
2001 INIT_LIST_HEAD(&sh
->lru
);
2002 atomic_set(&sh
->count
, 1);
2006 static int grow_one_stripe(struct r5conf
*conf
, gfp_t gfp
)
2008 struct stripe_head
*sh
;
2010 sh
= alloc_stripe(conf
->slab_cache
, gfp
);
2014 sh
->raid_conf
= conf
;
2016 if (grow_buffers(sh
, gfp
)) {
2018 kmem_cache_free(conf
->slab_cache
, sh
);
2021 sh
->hash_lock_index
=
2022 conf
->max_nr_stripes
% NR_STRIPE_HASH_LOCKS
;
2023 /* we just created an active stripe so... */
2024 atomic_inc(&conf
->active_stripes
);
2027 conf
->max_nr_stripes
++;
2031 static int grow_stripes(struct r5conf
*conf
, int num
)
2033 struct kmem_cache
*sc
;
2034 int devs
= max(conf
->raid_disks
, conf
->previous_raid_disks
);
2036 if (conf
->mddev
->gendisk
)
2037 sprintf(conf
->cache_name
[0],
2038 "raid%d-%s", conf
->level
, mdname(conf
->mddev
));
2040 sprintf(conf
->cache_name
[0],
2041 "raid%d-%p", conf
->level
, conf
->mddev
);
2042 sprintf(conf
->cache_name
[1], "%s-alt", conf
->cache_name
[0]);
2044 conf
->active_name
= 0;
2045 sc
= kmem_cache_create(conf
->cache_name
[conf
->active_name
],
2046 sizeof(struct stripe_head
)+(devs
-1)*sizeof(struct r5dev
),
2050 conf
->slab_cache
= sc
;
2051 conf
->pool_size
= devs
;
2053 if (!grow_one_stripe(conf
, GFP_KERNEL
))
2060 * scribble_len - return the required size of the scribble region
2061 * @num - total number of disks in the array
2063 * The size must be enough to contain:
2064 * 1/ a struct page pointer for each device in the array +2
2065 * 2/ room to convert each entry in (1) to its corresponding dma
2066 * (dma_map_page()) or page (page_address()) address.
2068 * Note: the +2 is for the destination buffers of the ddf/raid6 case where we
2069 * calculate over all devices (not just the data blocks), using zeros in place
2070 * of the P and Q blocks.
2072 static struct flex_array
*scribble_alloc(int num
, int cnt
, gfp_t flags
)
2074 struct flex_array
*ret
;
2077 len
= sizeof(struct page
*) * (num
+2) + sizeof(addr_conv_t
) * (num
+2);
2078 ret
= flex_array_alloc(len
, cnt
, flags
);
2081 /* always prealloc all elements, so no locking is required */
2082 if (flex_array_prealloc(ret
, 0, cnt
, flags
)) {
2083 flex_array_free(ret
);
2089 static int resize_chunks(struct r5conf
*conf
, int new_disks
, int new_sectors
)
2094 mddev_suspend(conf
->mddev
);
2096 for_each_present_cpu(cpu
) {
2097 struct raid5_percpu
*percpu
;
2098 struct flex_array
*scribble
;
2100 percpu
= per_cpu_ptr(conf
->percpu
, cpu
);
2101 scribble
= scribble_alloc(new_disks
,
2102 new_sectors
/ STRIPE_SECTORS
,
2106 flex_array_free(percpu
->scribble
);
2107 percpu
->scribble
= scribble
;
2114 mddev_resume(conf
->mddev
);
2118 static int resize_stripes(struct r5conf
*conf
, int newsize
)
2120 /* Make all the stripes able to hold 'newsize' devices.
2121 * New slots in each stripe get 'page' set to a new page.
2123 * This happens in stages:
2124 * 1/ create a new kmem_cache and allocate the required number of
2126 * 2/ gather all the old stripe_heads and transfer the pages across
2127 * to the new stripe_heads. This will have the side effect of
2128 * freezing the array as once all stripe_heads have been collected,
2129 * no IO will be possible. Old stripe heads are freed once their
2130 * pages have been transferred over, and the old kmem_cache is
2131 * freed when all stripes are done.
2132 * 3/ reallocate conf->disks to be suitable bigger. If this fails,
2133 * we simple return a failre status - no need to clean anything up.
2134 * 4/ allocate new pages for the new slots in the new stripe_heads.
2135 * If this fails, we don't bother trying the shrink the
2136 * stripe_heads down again, we just leave them as they are.
2137 * As each stripe_head is processed the new one is released into
2140 * Once step2 is started, we cannot afford to wait for a write,
2141 * so we use GFP_NOIO allocations.
2143 struct stripe_head
*osh
, *nsh
;
2144 LIST_HEAD(newstripes
);
2145 struct disk_info
*ndisks
;
2147 struct kmem_cache
*sc
;
2151 if (newsize
<= conf
->pool_size
)
2152 return 0; /* never bother to shrink */
2154 err
= md_allow_write(conf
->mddev
);
2159 sc
= kmem_cache_create(conf
->cache_name
[1-conf
->active_name
],
2160 sizeof(struct stripe_head
)+(newsize
-1)*sizeof(struct r5dev
),
2165 /* Need to ensure auto-resizing doesn't interfere */
2166 mutex_lock(&conf
->cache_size_mutex
);
2168 for (i
= conf
->max_nr_stripes
; i
; i
--) {
2169 nsh
= alloc_stripe(sc
, GFP_KERNEL
);
2173 nsh
->raid_conf
= conf
;
2174 list_add(&nsh
->lru
, &newstripes
);
2177 /* didn't get enough, give up */
2178 while (!list_empty(&newstripes
)) {
2179 nsh
= list_entry(newstripes
.next
, struct stripe_head
, lru
);
2180 list_del(&nsh
->lru
);
2181 kmem_cache_free(sc
, nsh
);
2183 kmem_cache_destroy(sc
);
2184 mutex_unlock(&conf
->cache_size_mutex
);
2187 /* Step 2 - Must use GFP_NOIO now.
2188 * OK, we have enough stripes, start collecting inactive
2189 * stripes and copying them over
2193 list_for_each_entry(nsh
, &newstripes
, lru
) {
2194 lock_device_hash_lock(conf
, hash
);
2195 wait_event_exclusive_cmd(conf
->wait_for_stripe
[hash
],
2196 !list_empty(conf
->inactive_list
+ hash
),
2197 unlock_device_hash_lock(conf
, hash
),
2198 lock_device_hash_lock(conf
, hash
));
2199 osh
= get_free_stripe(conf
, hash
);
2200 unlock_device_hash_lock(conf
, hash
);
2202 for(i
=0; i
<conf
->pool_size
; i
++) {
2203 nsh
->dev
[i
].page
= osh
->dev
[i
].page
;
2204 nsh
->dev
[i
].orig_page
= osh
->dev
[i
].page
;
2206 nsh
->hash_lock_index
= hash
;
2207 kmem_cache_free(conf
->slab_cache
, osh
);
2209 if (cnt
>= conf
->max_nr_stripes
/ NR_STRIPE_HASH_LOCKS
+
2210 !!((conf
->max_nr_stripes
% NR_STRIPE_HASH_LOCKS
) > hash
)) {
2215 kmem_cache_destroy(conf
->slab_cache
);
2218 * At this point, we are holding all the stripes so the array
2219 * is completely stalled, so now is a good time to resize
2220 * conf->disks and the scribble region
2222 ndisks
= kzalloc(newsize
* sizeof(struct disk_info
), GFP_NOIO
);
2224 for (i
=0; i
<conf
->raid_disks
; i
++)
2225 ndisks
[i
] = conf
->disks
[i
];
2227 conf
->disks
= ndisks
;
2231 mutex_unlock(&conf
->cache_size_mutex
);
2232 /* Step 4, return new stripes to service */
2233 while(!list_empty(&newstripes
)) {
2234 nsh
= list_entry(newstripes
.next
, struct stripe_head
, lru
);
2235 list_del_init(&nsh
->lru
);
2237 for (i
=conf
->raid_disks
; i
< newsize
; i
++)
2238 if (nsh
->dev
[i
].page
== NULL
) {
2239 struct page
*p
= alloc_page(GFP_NOIO
);
2240 nsh
->dev
[i
].page
= p
;
2241 nsh
->dev
[i
].orig_page
= p
;
2245 release_stripe(nsh
);
2247 /* critical section pass, GFP_NOIO no longer needed */
2249 conf
->slab_cache
= sc
;
2250 conf
->active_name
= 1-conf
->active_name
;
2252 conf
->pool_size
= newsize
;
2256 static int drop_one_stripe(struct r5conf
*conf
)
2258 struct stripe_head
*sh
;
2259 int hash
= (conf
->max_nr_stripes
- 1) & STRIPE_HASH_LOCKS_MASK
;
2261 spin_lock_irq(conf
->hash_locks
+ hash
);
2262 sh
= get_free_stripe(conf
, hash
);
2263 spin_unlock_irq(conf
->hash_locks
+ hash
);
2266 BUG_ON(atomic_read(&sh
->count
));
2268 kmem_cache_free(conf
->slab_cache
, sh
);
2269 atomic_dec(&conf
->active_stripes
);
2270 conf
->max_nr_stripes
--;
2274 static void shrink_stripes(struct r5conf
*conf
)
2276 while (conf
->max_nr_stripes
&&
2277 drop_one_stripe(conf
))
2280 if (conf
->slab_cache
)
2281 kmem_cache_destroy(conf
->slab_cache
);
2282 conf
->slab_cache
= NULL
;
2285 static void raid5_end_read_request(struct bio
* bi
, int error
)
2287 struct stripe_head
*sh
= bi
->bi_private
;
2288 struct r5conf
*conf
= sh
->raid_conf
;
2289 int disks
= sh
->disks
, i
;
2290 int uptodate
= test_bit(BIO_UPTODATE
, &bi
->bi_flags
);
2291 char b
[BDEVNAME_SIZE
];
2292 struct md_rdev
*rdev
= NULL
;
2295 for (i
=0 ; i
<disks
; i
++)
2296 if (bi
== &sh
->dev
[i
].req
)
2299 pr_debug("end_read_request %llu/%d, count: %d, uptodate %d.\n",
2300 (unsigned long long)sh
->sector
, i
, atomic_read(&sh
->count
),
2306 if (test_bit(R5_ReadRepl
, &sh
->dev
[i
].flags
))
2307 /* If replacement finished while this request was outstanding,
2308 * 'replacement' might be NULL already.
2309 * In that case it moved down to 'rdev'.
2310 * rdev is not removed until all requests are finished.
2312 rdev
= conf
->disks
[i
].replacement
;
2314 rdev
= conf
->disks
[i
].rdev
;
2316 if (use_new_offset(conf
, sh
))
2317 s
= sh
->sector
+ rdev
->new_data_offset
;
2319 s
= sh
->sector
+ rdev
->data_offset
;
2321 set_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
);
2322 if (test_bit(R5_ReadError
, &sh
->dev
[i
].flags
)) {
2323 /* Note that this cannot happen on a
2324 * replacement device. We just fail those on
2329 "md/raid:%s: read error corrected"
2330 " (%lu sectors at %llu on %s)\n",
2331 mdname(conf
->mddev
), STRIPE_SECTORS
,
2332 (unsigned long long)s
,
2333 bdevname(rdev
->bdev
, b
));
2334 atomic_add(STRIPE_SECTORS
, &rdev
->corrected_errors
);
2335 clear_bit(R5_ReadError
, &sh
->dev
[i
].flags
);
2336 clear_bit(R5_ReWrite
, &sh
->dev
[i
].flags
);
2337 } else if (test_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
))
2338 clear_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
);
2340 if (atomic_read(&rdev
->read_errors
))
2341 atomic_set(&rdev
->read_errors
, 0);
2343 const char *bdn
= bdevname(rdev
->bdev
, b
);
2347 clear_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
);
2348 atomic_inc(&rdev
->read_errors
);
2349 if (test_bit(R5_ReadRepl
, &sh
->dev
[i
].flags
))
2352 "md/raid:%s: read error on replacement device "
2353 "(sector %llu on %s).\n",
2354 mdname(conf
->mddev
),
2355 (unsigned long long)s
,
2357 else if (conf
->mddev
->degraded
>= conf
->max_degraded
) {
2361 "md/raid:%s: read error not correctable "
2362 "(sector %llu on %s).\n",
2363 mdname(conf
->mddev
),
2364 (unsigned long long)s
,
2366 } else if (test_bit(R5_ReWrite
, &sh
->dev
[i
].flags
)) {
2371 "md/raid:%s: read error NOT corrected!! "
2372 "(sector %llu on %s).\n",
2373 mdname(conf
->mddev
),
2374 (unsigned long long)s
,
2376 } else if (atomic_read(&rdev
->read_errors
)
2377 > conf
->max_nr_stripes
)
2379 "md/raid:%s: Too many read errors, failing device %s.\n",
2380 mdname(conf
->mddev
), bdn
);
2383 if (set_bad
&& test_bit(In_sync
, &rdev
->flags
)
2384 && !test_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
))
2387 if (test_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
)) {
2388 set_bit(R5_ReadError
, &sh
->dev
[i
].flags
);
2389 clear_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
);
2391 set_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
);
2393 clear_bit(R5_ReadError
, &sh
->dev
[i
].flags
);
2394 clear_bit(R5_ReWrite
, &sh
->dev
[i
].flags
);
2396 && test_bit(In_sync
, &rdev
->flags
)
2397 && rdev_set_badblocks(
2398 rdev
, sh
->sector
, STRIPE_SECTORS
, 0)))
2399 md_error(conf
->mddev
, rdev
);
2402 rdev_dec_pending(rdev
, conf
->mddev
);
2403 clear_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
2404 set_bit(STRIPE_HANDLE
, &sh
->state
);
2408 static void raid5_end_write_request(struct bio
*bi
, int error
)
2410 struct stripe_head
*sh
= bi
->bi_private
;
2411 struct r5conf
*conf
= sh
->raid_conf
;
2412 int disks
= sh
->disks
, i
;
2413 struct md_rdev
*uninitialized_var(rdev
);
2414 int uptodate
= test_bit(BIO_UPTODATE
, &bi
->bi_flags
);
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, uptodate: %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
&& !uptodate
&& !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
);
2482 if (sh
->batch_head
&& sh
!= sh
->batch_head
)
2483 release_stripe(sh
->batch_head
);
2486 static sector_t
compute_blocknr(struct stripe_head
*sh
, int i
, int previous
);
2488 static void raid5_build_block(struct stripe_head
*sh
, int i
, int previous
)
2490 struct r5dev
*dev
= &sh
->dev
[i
];
2492 bio_init(&dev
->req
);
2493 dev
->req
.bi_io_vec
= &dev
->vec
;
2494 dev
->req
.bi_max_vecs
= 1;
2495 dev
->req
.bi_private
= sh
;
2497 bio_init(&dev
->rreq
);
2498 dev
->rreq
.bi_io_vec
= &dev
->rvec
;
2499 dev
->rreq
.bi_max_vecs
= 1;
2500 dev
->rreq
.bi_private
= sh
;
2503 dev
->sector
= compute_blocknr(sh
, i
, previous
);
2506 static void error(struct mddev
*mddev
, struct md_rdev
*rdev
)
2508 char b
[BDEVNAME_SIZE
];
2509 struct r5conf
*conf
= mddev
->private;
2510 unsigned long flags
;
2511 pr_debug("raid456: error called\n");
2513 spin_lock_irqsave(&conf
->device_lock
, flags
);
2514 clear_bit(In_sync
, &rdev
->flags
);
2515 mddev
->degraded
= calc_degraded(conf
);
2516 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
2517 set_bit(MD_RECOVERY_INTR
, &mddev
->recovery
);
2519 set_bit(Blocked
, &rdev
->flags
);
2520 set_bit(Faulty
, &rdev
->flags
);
2521 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
2523 "md/raid:%s: Disk failure on %s, disabling device.\n"
2524 "md/raid:%s: Operation continuing on %d devices.\n",
2526 bdevname(rdev
->bdev
, b
),
2528 conf
->raid_disks
- mddev
->degraded
);
2532 * Input: a 'big' sector number,
2533 * Output: index of the data and parity disk, and the sector # in them.
2535 static sector_t
raid5_compute_sector(struct r5conf
*conf
, sector_t r_sector
,
2536 int previous
, int *dd_idx
,
2537 struct stripe_head
*sh
)
2539 sector_t stripe
, stripe2
;
2540 sector_t chunk_number
;
2541 unsigned int chunk_offset
;
2544 sector_t new_sector
;
2545 int algorithm
= previous
? conf
->prev_algo
2547 int sectors_per_chunk
= previous
? conf
->prev_chunk_sectors
2548 : conf
->chunk_sectors
;
2549 int raid_disks
= previous
? conf
->previous_raid_disks
2551 int data_disks
= raid_disks
- conf
->max_degraded
;
2553 /* First compute the information on this sector */
2556 * Compute the chunk number and the sector offset inside the chunk
2558 chunk_offset
= sector_div(r_sector
, sectors_per_chunk
);
2559 chunk_number
= r_sector
;
2562 * Compute the stripe number
2564 stripe
= chunk_number
;
2565 *dd_idx
= sector_div(stripe
, data_disks
);
2568 * Select the parity disk based on the user selected algorithm.
2570 pd_idx
= qd_idx
= -1;
2571 switch(conf
->level
) {
2573 pd_idx
= data_disks
;
2576 switch (algorithm
) {
2577 case ALGORITHM_LEFT_ASYMMETRIC
:
2578 pd_idx
= data_disks
- sector_div(stripe2
, raid_disks
);
2579 if (*dd_idx
>= pd_idx
)
2582 case ALGORITHM_RIGHT_ASYMMETRIC
:
2583 pd_idx
= sector_div(stripe2
, raid_disks
);
2584 if (*dd_idx
>= pd_idx
)
2587 case ALGORITHM_LEFT_SYMMETRIC
:
2588 pd_idx
= data_disks
- sector_div(stripe2
, raid_disks
);
2589 *dd_idx
= (pd_idx
+ 1 + *dd_idx
) % raid_disks
;
2591 case ALGORITHM_RIGHT_SYMMETRIC
:
2592 pd_idx
= sector_div(stripe2
, raid_disks
);
2593 *dd_idx
= (pd_idx
+ 1 + *dd_idx
) % raid_disks
;
2595 case ALGORITHM_PARITY_0
:
2599 case ALGORITHM_PARITY_N
:
2600 pd_idx
= data_disks
;
2608 switch (algorithm
) {
2609 case ALGORITHM_LEFT_ASYMMETRIC
:
2610 pd_idx
= raid_disks
- 1 - sector_div(stripe2
, raid_disks
);
2611 qd_idx
= pd_idx
+ 1;
2612 if (pd_idx
== raid_disks
-1) {
2613 (*dd_idx
)++; /* Q D D D P */
2615 } else if (*dd_idx
>= pd_idx
)
2616 (*dd_idx
) += 2; /* D D P Q D */
2618 case ALGORITHM_RIGHT_ASYMMETRIC
:
2619 pd_idx
= sector_div(stripe2
, raid_disks
);
2620 qd_idx
= pd_idx
+ 1;
2621 if (pd_idx
== raid_disks
-1) {
2622 (*dd_idx
)++; /* Q D D D P */
2624 } else if (*dd_idx
>= pd_idx
)
2625 (*dd_idx
) += 2; /* D D P Q D */
2627 case ALGORITHM_LEFT_SYMMETRIC
:
2628 pd_idx
= raid_disks
- 1 - sector_div(stripe2
, raid_disks
);
2629 qd_idx
= (pd_idx
+ 1) % raid_disks
;
2630 *dd_idx
= (pd_idx
+ 2 + *dd_idx
) % raid_disks
;
2632 case ALGORITHM_RIGHT_SYMMETRIC
:
2633 pd_idx
= sector_div(stripe2
, raid_disks
);
2634 qd_idx
= (pd_idx
+ 1) % raid_disks
;
2635 *dd_idx
= (pd_idx
+ 2 + *dd_idx
) % raid_disks
;
2638 case ALGORITHM_PARITY_0
:
2643 case ALGORITHM_PARITY_N
:
2644 pd_idx
= data_disks
;
2645 qd_idx
= data_disks
+ 1;
2648 case ALGORITHM_ROTATING_ZERO_RESTART
:
2649 /* Exactly the same as RIGHT_ASYMMETRIC, but or
2650 * of blocks for computing Q is different.
2652 pd_idx
= sector_div(stripe2
, raid_disks
);
2653 qd_idx
= pd_idx
+ 1;
2654 if (pd_idx
== raid_disks
-1) {
2655 (*dd_idx
)++; /* Q D D D P */
2657 } else if (*dd_idx
>= pd_idx
)
2658 (*dd_idx
) += 2; /* D D P Q D */
2662 case ALGORITHM_ROTATING_N_RESTART
:
2663 /* Same a left_asymmetric, by first stripe is
2664 * D D D P Q rather than
2668 pd_idx
= raid_disks
- 1 - sector_div(stripe2
, raid_disks
);
2669 qd_idx
= pd_idx
+ 1;
2670 if (pd_idx
== raid_disks
-1) {
2671 (*dd_idx
)++; /* Q D D D P */
2673 } else if (*dd_idx
>= pd_idx
)
2674 (*dd_idx
) += 2; /* D D P Q D */
2678 case ALGORITHM_ROTATING_N_CONTINUE
:
2679 /* Same as left_symmetric but Q is before P */
2680 pd_idx
= raid_disks
- 1 - sector_div(stripe2
, raid_disks
);
2681 qd_idx
= (pd_idx
+ raid_disks
- 1) % raid_disks
;
2682 *dd_idx
= (pd_idx
+ 1 + *dd_idx
) % raid_disks
;
2686 case ALGORITHM_LEFT_ASYMMETRIC_6
:
2687 /* RAID5 left_asymmetric, with Q on last device */
2688 pd_idx
= data_disks
- sector_div(stripe2
, raid_disks
-1);
2689 if (*dd_idx
>= pd_idx
)
2691 qd_idx
= raid_disks
- 1;
2694 case ALGORITHM_RIGHT_ASYMMETRIC_6
:
2695 pd_idx
= sector_div(stripe2
, raid_disks
-1);
2696 if (*dd_idx
>= pd_idx
)
2698 qd_idx
= raid_disks
- 1;
2701 case ALGORITHM_LEFT_SYMMETRIC_6
:
2702 pd_idx
= data_disks
- sector_div(stripe2
, raid_disks
-1);
2703 *dd_idx
= (pd_idx
+ 1 + *dd_idx
) % (raid_disks
-1);
2704 qd_idx
= raid_disks
- 1;
2707 case ALGORITHM_RIGHT_SYMMETRIC_6
:
2708 pd_idx
= sector_div(stripe2
, raid_disks
-1);
2709 *dd_idx
= (pd_idx
+ 1 + *dd_idx
) % (raid_disks
-1);
2710 qd_idx
= raid_disks
- 1;
2713 case ALGORITHM_PARITY_0_6
:
2716 qd_idx
= raid_disks
- 1;
2726 sh
->pd_idx
= pd_idx
;
2727 sh
->qd_idx
= qd_idx
;
2728 sh
->ddf_layout
= ddf_layout
;
2731 * Finally, compute the new sector number
2733 new_sector
= (sector_t
)stripe
* sectors_per_chunk
+ chunk_offset
;
2737 static sector_t
compute_blocknr(struct stripe_head
*sh
, int i
, int previous
)
2739 struct r5conf
*conf
= sh
->raid_conf
;
2740 int raid_disks
= sh
->disks
;
2741 int data_disks
= raid_disks
- conf
->max_degraded
;
2742 sector_t new_sector
= sh
->sector
, check
;
2743 int sectors_per_chunk
= previous
? conf
->prev_chunk_sectors
2744 : conf
->chunk_sectors
;
2745 int algorithm
= previous
? conf
->prev_algo
2749 sector_t chunk_number
;
2750 int dummy1
, dd_idx
= i
;
2752 struct stripe_head sh2
;
2754 chunk_offset
= sector_div(new_sector
, sectors_per_chunk
);
2755 stripe
= new_sector
;
2757 if (i
== sh
->pd_idx
)
2759 switch(conf
->level
) {
2762 switch (algorithm
) {
2763 case ALGORITHM_LEFT_ASYMMETRIC
:
2764 case ALGORITHM_RIGHT_ASYMMETRIC
:
2768 case ALGORITHM_LEFT_SYMMETRIC
:
2769 case ALGORITHM_RIGHT_SYMMETRIC
:
2772 i
-= (sh
->pd_idx
+ 1);
2774 case ALGORITHM_PARITY_0
:
2777 case ALGORITHM_PARITY_N
:
2784 if (i
== sh
->qd_idx
)
2785 return 0; /* It is the Q disk */
2786 switch (algorithm
) {
2787 case ALGORITHM_LEFT_ASYMMETRIC
:
2788 case ALGORITHM_RIGHT_ASYMMETRIC
:
2789 case ALGORITHM_ROTATING_ZERO_RESTART
:
2790 case ALGORITHM_ROTATING_N_RESTART
:
2791 if (sh
->pd_idx
== raid_disks
-1)
2792 i
--; /* Q D D D P */
2793 else if (i
> sh
->pd_idx
)
2794 i
-= 2; /* D D P Q D */
2796 case ALGORITHM_LEFT_SYMMETRIC
:
2797 case ALGORITHM_RIGHT_SYMMETRIC
:
2798 if (sh
->pd_idx
== raid_disks
-1)
2799 i
--; /* Q D D D P */
2804 i
-= (sh
->pd_idx
+ 2);
2807 case ALGORITHM_PARITY_0
:
2810 case ALGORITHM_PARITY_N
:
2812 case ALGORITHM_ROTATING_N_CONTINUE
:
2813 /* Like left_symmetric, but P is before Q */
2814 if (sh
->pd_idx
== 0)
2815 i
--; /* P D D D Q */
2820 i
-= (sh
->pd_idx
+ 1);
2823 case ALGORITHM_LEFT_ASYMMETRIC_6
:
2824 case ALGORITHM_RIGHT_ASYMMETRIC_6
:
2828 case ALGORITHM_LEFT_SYMMETRIC_6
:
2829 case ALGORITHM_RIGHT_SYMMETRIC_6
:
2831 i
+= data_disks
+ 1;
2832 i
-= (sh
->pd_idx
+ 1);
2834 case ALGORITHM_PARITY_0_6
:
2843 chunk_number
= stripe
* data_disks
+ i
;
2844 r_sector
= chunk_number
* sectors_per_chunk
+ chunk_offset
;
2846 check
= raid5_compute_sector(conf
, r_sector
,
2847 previous
, &dummy1
, &sh2
);
2848 if (check
!= sh
->sector
|| dummy1
!= dd_idx
|| sh2
.pd_idx
!= sh
->pd_idx
2849 || sh2
.qd_idx
!= sh
->qd_idx
) {
2850 printk(KERN_ERR
"md/raid:%s: compute_blocknr: map not correct\n",
2851 mdname(conf
->mddev
));
2858 schedule_reconstruction(struct stripe_head
*sh
, struct stripe_head_state
*s
,
2859 int rcw
, int expand
)
2861 int i
, pd_idx
= sh
->pd_idx
, qd_idx
= sh
->qd_idx
, disks
= sh
->disks
;
2862 struct r5conf
*conf
= sh
->raid_conf
;
2863 int level
= conf
->level
;
2867 for (i
= disks
; i
--; ) {
2868 struct r5dev
*dev
= &sh
->dev
[i
];
2871 set_bit(R5_LOCKED
, &dev
->flags
);
2872 set_bit(R5_Wantdrain
, &dev
->flags
);
2874 clear_bit(R5_UPTODATE
, &dev
->flags
);
2878 /* if we are not expanding this is a proper write request, and
2879 * there will be bios with new data to be drained into the
2884 /* False alarm, nothing to do */
2886 sh
->reconstruct_state
= reconstruct_state_drain_run
;
2887 set_bit(STRIPE_OP_BIODRAIN
, &s
->ops_request
);
2889 sh
->reconstruct_state
= reconstruct_state_run
;
2891 set_bit(STRIPE_OP_RECONSTRUCT
, &s
->ops_request
);
2893 if (s
->locked
+ conf
->max_degraded
== disks
)
2894 if (!test_and_set_bit(STRIPE_FULL_WRITE
, &sh
->state
))
2895 atomic_inc(&conf
->pending_full_writes
);
2897 BUG_ON(!(test_bit(R5_UPTODATE
, &sh
->dev
[pd_idx
].flags
) ||
2898 test_bit(R5_Wantcompute
, &sh
->dev
[pd_idx
].flags
)));
2899 BUG_ON(level
== 6 &&
2900 (!(test_bit(R5_UPTODATE
, &sh
->dev
[qd_idx
].flags
) ||
2901 test_bit(R5_Wantcompute
, &sh
->dev
[qd_idx
].flags
))));
2903 for (i
= disks
; i
--; ) {
2904 struct r5dev
*dev
= &sh
->dev
[i
];
2905 if (i
== pd_idx
|| i
== qd_idx
)
2909 (test_bit(R5_UPTODATE
, &dev
->flags
) ||
2910 test_bit(R5_Wantcompute
, &dev
->flags
))) {
2911 set_bit(R5_Wantdrain
, &dev
->flags
);
2912 set_bit(R5_LOCKED
, &dev
->flags
);
2913 clear_bit(R5_UPTODATE
, &dev
->flags
);
2918 /* False alarm - nothing to do */
2920 sh
->reconstruct_state
= reconstruct_state_prexor_drain_run
;
2921 set_bit(STRIPE_OP_PREXOR
, &s
->ops_request
);
2922 set_bit(STRIPE_OP_BIODRAIN
, &s
->ops_request
);
2923 set_bit(STRIPE_OP_RECONSTRUCT
, &s
->ops_request
);
2926 /* keep the parity disk(s) locked while asynchronous operations
2929 set_bit(R5_LOCKED
, &sh
->dev
[pd_idx
].flags
);
2930 clear_bit(R5_UPTODATE
, &sh
->dev
[pd_idx
].flags
);
2934 int qd_idx
= sh
->qd_idx
;
2935 struct r5dev
*dev
= &sh
->dev
[qd_idx
];
2937 set_bit(R5_LOCKED
, &dev
->flags
);
2938 clear_bit(R5_UPTODATE
, &dev
->flags
);
2942 pr_debug("%s: stripe %llu locked: %d ops_request: %lx\n",
2943 __func__
, (unsigned long long)sh
->sector
,
2944 s
->locked
, s
->ops_request
);
2948 * Each stripe/dev can have one or more bion attached.
2949 * toread/towrite point to the first in a chain.
2950 * The bi_next chain must be in order.
2952 static int add_stripe_bio(struct stripe_head
*sh
, struct bio
*bi
, int dd_idx
,
2953 int forwrite
, int previous
)
2956 struct r5conf
*conf
= sh
->raid_conf
;
2959 pr_debug("adding bi b#%llu to stripe s#%llu\n",
2960 (unsigned long long)bi
->bi_iter
.bi_sector
,
2961 (unsigned long long)sh
->sector
);
2964 * If several bio share a stripe. The bio bi_phys_segments acts as a
2965 * reference count to avoid race. The reference count should already be
2966 * increased before this function is called (for example, in
2967 * make_request()), so other bio sharing this stripe will not free the
2968 * stripe. If a stripe is owned by one stripe, the stripe lock will
2971 spin_lock_irq(&sh
->stripe_lock
);
2972 /* Don't allow new IO added to stripes in batch list */
2976 bip
= &sh
->dev
[dd_idx
].towrite
;
2980 bip
= &sh
->dev
[dd_idx
].toread
;
2981 while (*bip
&& (*bip
)->bi_iter
.bi_sector
< bi
->bi_iter
.bi_sector
) {
2982 if (bio_end_sector(*bip
) > bi
->bi_iter
.bi_sector
)
2984 bip
= & (*bip
)->bi_next
;
2986 if (*bip
&& (*bip
)->bi_iter
.bi_sector
< bio_end_sector(bi
))
2989 if (!forwrite
|| previous
)
2990 clear_bit(STRIPE_BATCH_READY
, &sh
->state
);
2992 BUG_ON(*bip
&& bi
->bi_next
&& (*bip
) != bi
->bi_next
);
2996 raid5_inc_bi_active_stripes(bi
);
2999 /* check if page is covered */
3000 sector_t sector
= sh
->dev
[dd_idx
].sector
;
3001 for (bi
=sh
->dev
[dd_idx
].towrite
;
3002 sector
< sh
->dev
[dd_idx
].sector
+ STRIPE_SECTORS
&&
3003 bi
&& bi
->bi_iter
.bi_sector
<= sector
;
3004 bi
= r5_next_bio(bi
, sh
->dev
[dd_idx
].sector
)) {
3005 if (bio_end_sector(bi
) >= sector
)
3006 sector
= bio_end_sector(bi
);
3008 if (sector
>= sh
->dev
[dd_idx
].sector
+ STRIPE_SECTORS
)
3009 if (!test_and_set_bit(R5_OVERWRITE
, &sh
->dev
[dd_idx
].flags
))
3010 sh
->overwrite_disks
++;
3013 pr_debug("added bi b#%llu to stripe s#%llu, disk %d.\n",
3014 (unsigned long long)(*bip
)->bi_iter
.bi_sector
,
3015 (unsigned long long)sh
->sector
, dd_idx
);
3017 if (conf
->mddev
->bitmap
&& firstwrite
) {
3018 /* Cannot hold spinlock over bitmap_startwrite,
3019 * but must ensure this isn't added to a batch until
3020 * we have added to the bitmap and set bm_seq.
3021 * So set STRIPE_BITMAP_PENDING to prevent
3023 * If multiple add_stripe_bio() calls race here they
3024 * much all set STRIPE_BITMAP_PENDING. So only the first one
3025 * to complete "bitmap_startwrite" gets to set
3026 * STRIPE_BIT_DELAY. This is important as once a stripe
3027 * is added to a batch, STRIPE_BIT_DELAY cannot be changed
3030 set_bit(STRIPE_BITMAP_PENDING
, &sh
->state
);
3031 spin_unlock_irq(&sh
->stripe_lock
);
3032 bitmap_startwrite(conf
->mddev
->bitmap
, sh
->sector
,
3034 spin_lock_irq(&sh
->stripe_lock
);
3035 clear_bit(STRIPE_BITMAP_PENDING
, &sh
->state
);
3036 if (!sh
->batch_head
) {
3037 sh
->bm_seq
= conf
->seq_flush
+1;
3038 set_bit(STRIPE_BIT_DELAY
, &sh
->state
);
3041 spin_unlock_irq(&sh
->stripe_lock
);
3043 if (stripe_can_batch(sh
))
3044 stripe_add_to_batch_list(conf
, sh
);
3048 set_bit(R5_Overlap
, &sh
->dev
[dd_idx
].flags
);
3049 spin_unlock_irq(&sh
->stripe_lock
);
3053 static void end_reshape(struct r5conf
*conf
);
3055 static void stripe_set_idx(sector_t stripe
, struct r5conf
*conf
, int previous
,
3056 struct stripe_head
*sh
)
3058 int sectors_per_chunk
=
3059 previous
? conf
->prev_chunk_sectors
: conf
->chunk_sectors
;
3061 int chunk_offset
= sector_div(stripe
, sectors_per_chunk
);
3062 int disks
= previous
? conf
->previous_raid_disks
: conf
->raid_disks
;
3064 raid5_compute_sector(conf
,
3065 stripe
* (disks
- conf
->max_degraded
)
3066 *sectors_per_chunk
+ chunk_offset
,
3072 handle_failed_stripe(struct r5conf
*conf
, struct stripe_head
*sh
,
3073 struct stripe_head_state
*s
, int disks
,
3074 struct bio
**return_bi
)
3077 BUG_ON(sh
->batch_head
);
3078 for (i
= disks
; i
--; ) {
3082 if (test_bit(R5_ReadError
, &sh
->dev
[i
].flags
)) {
3083 struct md_rdev
*rdev
;
3085 rdev
= rcu_dereference(conf
->disks
[i
].rdev
);
3086 if (rdev
&& test_bit(In_sync
, &rdev
->flags
))
3087 atomic_inc(&rdev
->nr_pending
);
3092 if (!rdev_set_badblocks(
3096 md_error(conf
->mddev
, rdev
);
3097 rdev_dec_pending(rdev
, conf
->mddev
);
3100 spin_lock_irq(&sh
->stripe_lock
);
3101 /* fail all writes first */
3102 bi
= sh
->dev
[i
].towrite
;
3103 sh
->dev
[i
].towrite
= NULL
;
3104 sh
->overwrite_disks
= 0;
3105 spin_unlock_irq(&sh
->stripe_lock
);
3109 if (test_and_clear_bit(R5_Overlap
, &sh
->dev
[i
].flags
))
3110 wake_up(&conf
->wait_for_overlap
);
3112 while (bi
&& bi
->bi_iter
.bi_sector
<
3113 sh
->dev
[i
].sector
+ STRIPE_SECTORS
) {
3114 struct bio
*nextbi
= r5_next_bio(bi
, sh
->dev
[i
].sector
);
3115 clear_bit(BIO_UPTODATE
, &bi
->bi_flags
);
3116 if (!raid5_dec_bi_active_stripes(bi
)) {
3117 md_write_end(conf
->mddev
);
3118 bi
->bi_next
= *return_bi
;
3124 bitmap_endwrite(conf
->mddev
->bitmap
, sh
->sector
,
3125 STRIPE_SECTORS
, 0, 0);
3127 /* and fail all 'written' */
3128 bi
= sh
->dev
[i
].written
;
3129 sh
->dev
[i
].written
= NULL
;
3130 if (test_and_clear_bit(R5_SkipCopy
, &sh
->dev
[i
].flags
)) {
3131 WARN_ON(test_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
));
3132 sh
->dev
[i
].page
= sh
->dev
[i
].orig_page
;
3135 if (bi
) bitmap_end
= 1;
3136 while (bi
&& bi
->bi_iter
.bi_sector
<
3137 sh
->dev
[i
].sector
+ STRIPE_SECTORS
) {
3138 struct bio
*bi2
= r5_next_bio(bi
, sh
->dev
[i
].sector
);
3139 clear_bit(BIO_UPTODATE
, &bi
->bi_flags
);
3140 if (!raid5_dec_bi_active_stripes(bi
)) {
3141 md_write_end(conf
->mddev
);
3142 bi
->bi_next
= *return_bi
;
3148 /* fail any reads if this device is non-operational and
3149 * the data has not reached the cache yet.
3151 if (!test_bit(R5_Wantfill
, &sh
->dev
[i
].flags
) &&
3152 (!test_bit(R5_Insync
, &sh
->dev
[i
].flags
) ||
3153 test_bit(R5_ReadError
, &sh
->dev
[i
].flags
))) {
3154 spin_lock_irq(&sh
->stripe_lock
);
3155 bi
= sh
->dev
[i
].toread
;
3156 sh
->dev
[i
].toread
= NULL
;
3157 spin_unlock_irq(&sh
->stripe_lock
);
3158 if (test_and_clear_bit(R5_Overlap
, &sh
->dev
[i
].flags
))
3159 wake_up(&conf
->wait_for_overlap
);
3160 while (bi
&& bi
->bi_iter
.bi_sector
<
3161 sh
->dev
[i
].sector
+ STRIPE_SECTORS
) {
3162 struct bio
*nextbi
=
3163 r5_next_bio(bi
, sh
->dev
[i
].sector
);
3164 clear_bit(BIO_UPTODATE
, &bi
->bi_flags
);
3165 if (!raid5_dec_bi_active_stripes(bi
)) {
3166 bi
->bi_next
= *return_bi
;
3173 bitmap_endwrite(conf
->mddev
->bitmap
, sh
->sector
,
3174 STRIPE_SECTORS
, 0, 0);
3175 /* If we were in the middle of a write the parity block might
3176 * still be locked - so just clear all R5_LOCKED flags
3178 clear_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
3181 if (test_and_clear_bit(STRIPE_FULL_WRITE
, &sh
->state
))
3182 if (atomic_dec_and_test(&conf
->pending_full_writes
))
3183 md_wakeup_thread(conf
->mddev
->thread
);
3187 handle_failed_sync(struct r5conf
*conf
, struct stripe_head
*sh
,
3188 struct stripe_head_state
*s
)
3193 BUG_ON(sh
->batch_head
);
3194 clear_bit(STRIPE_SYNCING
, &sh
->state
);
3195 if (test_and_clear_bit(R5_Overlap
, &sh
->dev
[sh
->pd_idx
].flags
))
3196 wake_up(&conf
->wait_for_overlap
);
3199 /* There is nothing more to do for sync/check/repair.
3200 * Don't even need to abort as that is handled elsewhere
3201 * if needed, and not always wanted e.g. if there is a known
3203 * For recover/replace we need to record a bad block on all
3204 * non-sync devices, or abort the recovery
3206 if (test_bit(MD_RECOVERY_RECOVER
, &conf
->mddev
->recovery
)) {
3207 /* During recovery devices cannot be removed, so
3208 * locking and refcounting of rdevs is not needed
3210 for (i
= 0; i
< conf
->raid_disks
; i
++) {
3211 struct md_rdev
*rdev
= conf
->disks
[i
].rdev
;
3213 && !test_bit(Faulty
, &rdev
->flags
)
3214 && !test_bit(In_sync
, &rdev
->flags
)
3215 && !rdev_set_badblocks(rdev
, sh
->sector
,
3218 rdev
= conf
->disks
[i
].replacement
;
3220 && !test_bit(Faulty
, &rdev
->flags
)
3221 && !test_bit(In_sync
, &rdev
->flags
)
3222 && !rdev_set_badblocks(rdev
, sh
->sector
,
3227 conf
->recovery_disabled
=
3228 conf
->mddev
->recovery_disabled
;
3230 md_done_sync(conf
->mddev
, STRIPE_SECTORS
, !abort
);
3233 static int want_replace(struct stripe_head
*sh
, int disk_idx
)
3235 struct md_rdev
*rdev
;
3237 /* Doing recovery so rcu locking not required */
3238 rdev
= sh
->raid_conf
->disks
[disk_idx
].replacement
;
3240 && !test_bit(Faulty
, &rdev
->flags
)
3241 && !test_bit(In_sync
, &rdev
->flags
)
3242 && (rdev
->recovery_offset
<= sh
->sector
3243 || rdev
->mddev
->recovery_cp
<= sh
->sector
))
3249 /* fetch_block - checks the given member device to see if its data needs
3250 * to be read or computed to satisfy a request.
3252 * Returns 1 when no more member devices need to be checked, otherwise returns
3253 * 0 to tell the loop in handle_stripe_fill to continue
3256 static int need_this_block(struct stripe_head
*sh
, struct stripe_head_state
*s
,
3257 int disk_idx
, int disks
)
3259 struct r5dev
*dev
= &sh
->dev
[disk_idx
];
3260 struct r5dev
*fdev
[2] = { &sh
->dev
[s
->failed_num
[0]],
3261 &sh
->dev
[s
->failed_num
[1]] };
3265 if (test_bit(R5_LOCKED
, &dev
->flags
) ||
3266 test_bit(R5_UPTODATE
, &dev
->flags
))
3267 /* No point reading this as we already have it or have
3268 * decided to get it.
3273 (dev
->towrite
&& !test_bit(R5_OVERWRITE
, &dev
->flags
)))
3274 /* We need this block to directly satisfy a request */
3277 if (s
->syncing
|| s
->expanding
||
3278 (s
->replacing
&& want_replace(sh
, disk_idx
)))
3279 /* When syncing, or expanding we read everything.
3280 * When replacing, we need the replaced block.
3284 if ((s
->failed
>= 1 && fdev
[0]->toread
) ||
3285 (s
->failed
>= 2 && fdev
[1]->toread
))
3286 /* If we want to read from a failed device, then
3287 * we need to actually read every other device.
3291 /* Sometimes neither read-modify-write nor reconstruct-write
3292 * cycles can work. In those cases we read every block we
3293 * can. Then the parity-update is certain to have enough to
3295 * This can only be a problem when we need to write something,
3296 * and some device has failed. If either of those tests
3297 * fail we need look no further.
3299 if (!s
->failed
|| !s
->to_write
)
3302 if (test_bit(R5_Insync
, &dev
->flags
) &&
3303 !test_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
3304 /* Pre-reads at not permitted until after short delay
3305 * to gather multiple requests. However if this
3306 * device is no Insync, the block could only be be computed
3307 * and there is no need to delay that.
3311 for (i
= 0; i
< s
->failed
; i
++) {
3312 if (fdev
[i
]->towrite
&&
3313 !test_bit(R5_UPTODATE
, &fdev
[i
]->flags
) &&
3314 !test_bit(R5_OVERWRITE
, &fdev
[i
]->flags
))
3315 /* If we have a partial write to a failed
3316 * device, then we will need to reconstruct
3317 * the content of that device, so all other
3318 * devices must be read.
3323 /* If we are forced to do a reconstruct-write, either because
3324 * the current RAID6 implementation only supports that, or
3325 * or because parity cannot be trusted and we are currently
3326 * recovering it, there is extra need to be careful.
3327 * If one of the devices that we would need to read, because
3328 * it is not being overwritten (and maybe not written at all)
3329 * is missing/faulty, then we need to read everything we can.
3331 if (sh
->raid_conf
->level
!= 6 &&
3332 sh
->sector
< sh
->raid_conf
->mddev
->recovery_cp
)
3333 /* reconstruct-write isn't being forced */
3335 for (i
= 0; i
< s
->failed
; i
++) {
3336 if (s
->failed_num
[i
] != sh
->pd_idx
&&
3337 s
->failed_num
[i
] != sh
->qd_idx
&&
3338 !test_bit(R5_UPTODATE
, &fdev
[i
]->flags
) &&
3339 !test_bit(R5_OVERWRITE
, &fdev
[i
]->flags
))
3346 static int fetch_block(struct stripe_head
*sh
, struct stripe_head_state
*s
,
3347 int disk_idx
, int disks
)
3349 struct r5dev
*dev
= &sh
->dev
[disk_idx
];
3351 /* is the data in this block needed, and can we get it? */
3352 if (need_this_block(sh
, s
, disk_idx
, disks
)) {
3353 /* we would like to get this block, possibly by computing it,
3354 * otherwise read it if the backing disk is insync
3356 BUG_ON(test_bit(R5_Wantcompute
, &dev
->flags
));
3357 BUG_ON(test_bit(R5_Wantread
, &dev
->flags
));
3358 BUG_ON(sh
->batch_head
);
3359 if ((s
->uptodate
== disks
- 1) &&
3360 (s
->failed
&& (disk_idx
== s
->failed_num
[0] ||
3361 disk_idx
== s
->failed_num
[1]))) {
3362 /* have disk failed, and we're requested to fetch it;
3365 pr_debug("Computing stripe %llu block %d\n",
3366 (unsigned long long)sh
->sector
, disk_idx
);
3367 set_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
3368 set_bit(STRIPE_OP_COMPUTE_BLK
, &s
->ops_request
);
3369 set_bit(R5_Wantcompute
, &dev
->flags
);
3370 sh
->ops
.target
= disk_idx
;
3371 sh
->ops
.target2
= -1; /* no 2nd target */
3373 /* Careful: from this point on 'uptodate' is in the eye
3374 * of raid_run_ops which services 'compute' operations
3375 * before writes. R5_Wantcompute flags a block that will
3376 * be R5_UPTODATE by the time it is needed for a
3377 * subsequent operation.
3381 } else if (s
->uptodate
== disks
-2 && s
->failed
>= 2) {
3382 /* Computing 2-failure is *very* expensive; only
3383 * do it if failed >= 2
3386 for (other
= disks
; other
--; ) {
3387 if (other
== disk_idx
)
3389 if (!test_bit(R5_UPTODATE
,
3390 &sh
->dev
[other
].flags
))
3394 pr_debug("Computing stripe %llu blocks %d,%d\n",
3395 (unsigned long long)sh
->sector
,
3397 set_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
3398 set_bit(STRIPE_OP_COMPUTE_BLK
, &s
->ops_request
);
3399 set_bit(R5_Wantcompute
, &sh
->dev
[disk_idx
].flags
);
3400 set_bit(R5_Wantcompute
, &sh
->dev
[other
].flags
);
3401 sh
->ops
.target
= disk_idx
;
3402 sh
->ops
.target2
= other
;
3406 } else if (test_bit(R5_Insync
, &dev
->flags
)) {
3407 set_bit(R5_LOCKED
, &dev
->flags
);
3408 set_bit(R5_Wantread
, &dev
->flags
);
3410 pr_debug("Reading block %d (sync=%d)\n",
3411 disk_idx
, s
->syncing
);
3419 * handle_stripe_fill - read or compute data to satisfy pending requests.
3421 static void handle_stripe_fill(struct stripe_head
*sh
,
3422 struct stripe_head_state
*s
,
3427 /* look for blocks to read/compute, skip this if a compute
3428 * is already in flight, or if the stripe contents are in the
3429 * midst of changing due to a write
3431 if (!test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
) && !sh
->check_state
&&
3432 !sh
->reconstruct_state
)
3433 for (i
= disks
; i
--; )
3434 if (fetch_block(sh
, s
, i
, disks
))
3436 set_bit(STRIPE_HANDLE
, &sh
->state
);
3439 static void break_stripe_batch_list(struct stripe_head
*head_sh
,
3440 unsigned long handle_flags
);
3441 /* handle_stripe_clean_event
3442 * any written block on an uptodate or failed drive can be returned.
3443 * Note that if we 'wrote' to a failed drive, it will be UPTODATE, but
3444 * never LOCKED, so we don't need to test 'failed' directly.
3446 static void handle_stripe_clean_event(struct r5conf
*conf
,
3447 struct stripe_head
*sh
, int disks
, struct bio
**return_bi
)
3451 int discard_pending
= 0;
3452 struct stripe_head
*head_sh
= sh
;
3453 bool do_endio
= false;
3455 for (i
= disks
; i
--; )
3456 if (sh
->dev
[i
].written
) {
3458 if (!test_bit(R5_LOCKED
, &dev
->flags
) &&
3459 (test_bit(R5_UPTODATE
, &dev
->flags
) ||
3460 test_bit(R5_Discard
, &dev
->flags
) ||
3461 test_bit(R5_SkipCopy
, &dev
->flags
))) {
3462 /* We can return any write requests */
3463 struct bio
*wbi
, *wbi2
;
3464 pr_debug("Return write for disc %d\n", i
);
3465 if (test_and_clear_bit(R5_Discard
, &dev
->flags
))
3466 clear_bit(R5_UPTODATE
, &dev
->flags
);
3467 if (test_and_clear_bit(R5_SkipCopy
, &dev
->flags
)) {
3468 WARN_ON(test_bit(R5_UPTODATE
, &dev
->flags
));
3473 dev
->page
= dev
->orig_page
;
3475 dev
->written
= NULL
;
3476 while (wbi
&& wbi
->bi_iter
.bi_sector
<
3477 dev
->sector
+ STRIPE_SECTORS
) {
3478 wbi2
= r5_next_bio(wbi
, dev
->sector
);
3479 if (!raid5_dec_bi_active_stripes(wbi
)) {
3480 md_write_end(conf
->mddev
);
3481 wbi
->bi_next
= *return_bi
;
3486 bitmap_endwrite(conf
->mddev
->bitmap
, sh
->sector
,
3488 !test_bit(STRIPE_DEGRADED
, &sh
->state
),
3490 if (head_sh
->batch_head
) {
3491 sh
= list_first_entry(&sh
->batch_list
,
3494 if (sh
!= head_sh
) {
3501 } else if (test_bit(R5_Discard
, &dev
->flags
))
3502 discard_pending
= 1;
3503 WARN_ON(test_bit(R5_SkipCopy
, &dev
->flags
));
3504 WARN_ON(dev
->page
!= dev
->orig_page
);
3506 if (!discard_pending
&&
3507 test_bit(R5_Discard
, &sh
->dev
[sh
->pd_idx
].flags
)) {
3508 clear_bit(R5_Discard
, &sh
->dev
[sh
->pd_idx
].flags
);
3509 clear_bit(R5_UPTODATE
, &sh
->dev
[sh
->pd_idx
].flags
);
3510 if (sh
->qd_idx
>= 0) {
3511 clear_bit(R5_Discard
, &sh
->dev
[sh
->qd_idx
].flags
);
3512 clear_bit(R5_UPTODATE
, &sh
->dev
[sh
->qd_idx
].flags
);
3514 /* now that discard is done we can proceed with any sync */
3515 clear_bit(STRIPE_DISCARD
, &sh
->state
);
3517 * SCSI discard will change some bio fields and the stripe has
3518 * no updated data, so remove it from hash list and the stripe
3519 * will be reinitialized
3521 spin_lock_irq(&conf
->device_lock
);
3524 if (head_sh
->batch_head
) {
3525 sh
= list_first_entry(&sh
->batch_list
,
3526 struct stripe_head
, batch_list
);
3530 spin_unlock_irq(&conf
->device_lock
);
3533 if (test_bit(STRIPE_SYNC_REQUESTED
, &sh
->state
))
3534 set_bit(STRIPE_HANDLE
, &sh
->state
);
3538 if (test_and_clear_bit(STRIPE_FULL_WRITE
, &sh
->state
))
3539 if (atomic_dec_and_test(&conf
->pending_full_writes
))
3540 md_wakeup_thread(conf
->mddev
->thread
);
3542 if (head_sh
->batch_head
&& do_endio
)
3543 break_stripe_batch_list(head_sh
, STRIPE_EXPAND_SYNC_FLAGS
);
3546 static void handle_stripe_dirtying(struct r5conf
*conf
,
3547 struct stripe_head
*sh
,
3548 struct stripe_head_state
*s
,
3551 int rmw
= 0, rcw
= 0, i
;
3552 sector_t recovery_cp
= conf
->mddev
->recovery_cp
;
3554 /* Check whether resync is now happening or should start.
3555 * If yes, then the array is dirty (after unclean shutdown or
3556 * initial creation), so parity in some stripes might be inconsistent.
3557 * In this case, we need to always do reconstruct-write, to ensure
3558 * that in case of drive failure or read-error correction, we
3559 * generate correct data from the parity.
3561 if (conf
->rmw_level
== PARITY_DISABLE_RMW
||
3562 (recovery_cp
< MaxSector
&& sh
->sector
>= recovery_cp
&&
3564 /* Calculate the real rcw later - for now make it
3565 * look like rcw is cheaper
3568 pr_debug("force RCW rmw_level=%u, recovery_cp=%llu sh->sector=%llu\n",
3569 conf
->rmw_level
, (unsigned long long)recovery_cp
,
3570 (unsigned long long)sh
->sector
);
3571 } else for (i
= disks
; i
--; ) {
3572 /* would I have to read this buffer for read_modify_write */
3573 struct r5dev
*dev
= &sh
->dev
[i
];
3574 if ((dev
->towrite
|| i
== sh
->pd_idx
|| i
== sh
->qd_idx
) &&
3575 !test_bit(R5_LOCKED
, &dev
->flags
) &&
3576 !(test_bit(R5_UPTODATE
, &dev
->flags
) ||
3577 test_bit(R5_Wantcompute
, &dev
->flags
))) {
3578 if (test_bit(R5_Insync
, &dev
->flags
))
3581 rmw
+= 2*disks
; /* cannot read it */
3583 /* Would I have to read this buffer for reconstruct_write */
3584 if (!test_bit(R5_OVERWRITE
, &dev
->flags
) &&
3585 i
!= sh
->pd_idx
&& i
!= sh
->qd_idx
&&
3586 !test_bit(R5_LOCKED
, &dev
->flags
) &&
3587 !(test_bit(R5_UPTODATE
, &dev
->flags
) ||
3588 test_bit(R5_Wantcompute
, &dev
->flags
))) {
3589 if (test_bit(R5_Insync
, &dev
->flags
))
3595 pr_debug("for sector %llu, rmw=%d rcw=%d\n",
3596 (unsigned long long)sh
->sector
, rmw
, rcw
);
3597 set_bit(STRIPE_HANDLE
, &sh
->state
);
3598 if ((rmw
< rcw
|| (rmw
== rcw
&& conf
->rmw_level
== PARITY_ENABLE_RMW
)) && rmw
> 0) {
3599 /* prefer read-modify-write, but need to get some data */
3600 if (conf
->mddev
->queue
)
3601 blk_add_trace_msg(conf
->mddev
->queue
,
3602 "raid5 rmw %llu %d",
3603 (unsigned long long)sh
->sector
, rmw
);
3604 for (i
= disks
; i
--; ) {
3605 struct r5dev
*dev
= &sh
->dev
[i
];
3606 if ((dev
->towrite
|| i
== sh
->pd_idx
|| i
== sh
->qd_idx
) &&
3607 !test_bit(R5_LOCKED
, &dev
->flags
) &&
3608 !(test_bit(R5_UPTODATE
, &dev
->flags
) ||
3609 test_bit(R5_Wantcompute
, &dev
->flags
)) &&
3610 test_bit(R5_Insync
, &dev
->flags
)) {
3611 if (test_bit(STRIPE_PREREAD_ACTIVE
,
3613 pr_debug("Read_old block %d for r-m-w\n",
3615 set_bit(R5_LOCKED
, &dev
->flags
);
3616 set_bit(R5_Wantread
, &dev
->flags
);
3619 set_bit(STRIPE_DELAYED
, &sh
->state
);
3620 set_bit(STRIPE_HANDLE
, &sh
->state
);
3625 if ((rcw
< rmw
|| (rcw
== rmw
&& conf
->rmw_level
!= PARITY_ENABLE_RMW
)) && rcw
> 0) {
3626 /* want reconstruct write, but need to get some data */
3629 for (i
= disks
; i
--; ) {
3630 struct r5dev
*dev
= &sh
->dev
[i
];
3631 if (!test_bit(R5_OVERWRITE
, &dev
->flags
) &&
3632 i
!= sh
->pd_idx
&& i
!= sh
->qd_idx
&&
3633 !test_bit(R5_LOCKED
, &dev
->flags
) &&
3634 !(test_bit(R5_UPTODATE
, &dev
->flags
) ||
3635 test_bit(R5_Wantcompute
, &dev
->flags
))) {
3637 if (test_bit(R5_Insync
, &dev
->flags
) &&
3638 test_bit(STRIPE_PREREAD_ACTIVE
,
3640 pr_debug("Read_old block "
3641 "%d for Reconstruct\n", i
);
3642 set_bit(R5_LOCKED
, &dev
->flags
);
3643 set_bit(R5_Wantread
, &dev
->flags
);
3647 set_bit(STRIPE_DELAYED
, &sh
->state
);
3648 set_bit(STRIPE_HANDLE
, &sh
->state
);
3652 if (rcw
&& conf
->mddev
->queue
)
3653 blk_add_trace_msg(conf
->mddev
->queue
, "raid5 rcw %llu %d %d %d",
3654 (unsigned long long)sh
->sector
,
3655 rcw
, qread
, test_bit(STRIPE_DELAYED
, &sh
->state
));
3658 if (rcw
> disks
&& rmw
> disks
&&
3659 !test_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
3660 set_bit(STRIPE_DELAYED
, &sh
->state
);
3662 /* now if nothing is locked, and if we have enough data,
3663 * we can start a write request
3665 /* since handle_stripe can be called at any time we need to handle the
3666 * case where a compute block operation has been submitted and then a
3667 * subsequent call wants to start a write request. raid_run_ops only
3668 * handles the case where compute block and reconstruct are requested
3669 * simultaneously. If this is not the case then new writes need to be
3670 * held off until the compute completes.
3672 if ((s
->req_compute
|| !test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
)) &&
3673 (s
->locked
== 0 && (rcw
== 0 || rmw
== 0) &&
3674 !test_bit(STRIPE_BIT_DELAY
, &sh
->state
)))
3675 schedule_reconstruction(sh
, s
, rcw
== 0, 0);
3678 static void handle_parity_checks5(struct r5conf
*conf
, struct stripe_head
*sh
,
3679 struct stripe_head_state
*s
, int disks
)
3681 struct r5dev
*dev
= NULL
;
3683 BUG_ON(sh
->batch_head
);
3684 set_bit(STRIPE_HANDLE
, &sh
->state
);
3686 switch (sh
->check_state
) {
3687 case check_state_idle
:
3688 /* start a new check operation if there are no failures */
3689 if (s
->failed
== 0) {
3690 BUG_ON(s
->uptodate
!= disks
);
3691 sh
->check_state
= check_state_run
;
3692 set_bit(STRIPE_OP_CHECK
, &s
->ops_request
);
3693 clear_bit(R5_UPTODATE
, &sh
->dev
[sh
->pd_idx
].flags
);
3697 dev
= &sh
->dev
[s
->failed_num
[0]];
3699 case check_state_compute_result
:
3700 sh
->check_state
= check_state_idle
;
3702 dev
= &sh
->dev
[sh
->pd_idx
];
3704 /* check that a write has not made the stripe insync */
3705 if (test_bit(STRIPE_INSYNC
, &sh
->state
))
3708 /* either failed parity check, or recovery is happening */
3709 BUG_ON(!test_bit(R5_UPTODATE
, &dev
->flags
));
3710 BUG_ON(s
->uptodate
!= disks
);
3712 set_bit(R5_LOCKED
, &dev
->flags
);
3714 set_bit(R5_Wantwrite
, &dev
->flags
);
3716 clear_bit(STRIPE_DEGRADED
, &sh
->state
);
3717 set_bit(STRIPE_INSYNC
, &sh
->state
);
3719 case check_state_run
:
3720 break; /* we will be called again upon completion */
3721 case check_state_check_result
:
3722 sh
->check_state
= check_state_idle
;
3724 /* if a failure occurred during the check operation, leave
3725 * STRIPE_INSYNC not set and let the stripe be handled again
3730 /* handle a successful check operation, if parity is correct
3731 * we are done. Otherwise update the mismatch count and repair
3732 * parity if !MD_RECOVERY_CHECK
3734 if ((sh
->ops
.zero_sum_result
& SUM_CHECK_P_RESULT
) == 0)
3735 /* parity is correct (on disc,
3736 * not in buffer any more)
3738 set_bit(STRIPE_INSYNC
, &sh
->state
);
3740 atomic64_add(STRIPE_SECTORS
, &conf
->mddev
->resync_mismatches
);
3741 if (test_bit(MD_RECOVERY_CHECK
, &conf
->mddev
->recovery
))
3742 /* don't try to repair!! */
3743 set_bit(STRIPE_INSYNC
, &sh
->state
);
3745 sh
->check_state
= check_state_compute_run
;
3746 set_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
3747 set_bit(STRIPE_OP_COMPUTE_BLK
, &s
->ops_request
);
3748 set_bit(R5_Wantcompute
,
3749 &sh
->dev
[sh
->pd_idx
].flags
);
3750 sh
->ops
.target
= sh
->pd_idx
;
3751 sh
->ops
.target2
= -1;
3756 case check_state_compute_run
:
3759 printk(KERN_ERR
"%s: unknown check_state: %d sector: %llu\n",
3760 __func__
, sh
->check_state
,
3761 (unsigned long long) sh
->sector
);
3766 static void handle_parity_checks6(struct r5conf
*conf
, struct stripe_head
*sh
,
3767 struct stripe_head_state
*s
,
3770 int pd_idx
= sh
->pd_idx
;
3771 int qd_idx
= sh
->qd_idx
;
3774 BUG_ON(sh
->batch_head
);
3775 set_bit(STRIPE_HANDLE
, &sh
->state
);
3777 BUG_ON(s
->failed
> 2);
3779 /* Want to check and possibly repair P and Q.
3780 * However there could be one 'failed' device, in which
3781 * case we can only check one of them, possibly using the
3782 * other to generate missing data
3785 switch (sh
->check_state
) {
3786 case check_state_idle
:
3787 /* start a new check operation if there are < 2 failures */
3788 if (s
->failed
== s
->q_failed
) {
3789 /* The only possible failed device holds Q, so it
3790 * makes sense to check P (If anything else were failed,
3791 * we would have used P to recreate it).
3793 sh
->check_state
= check_state_run
;
3795 if (!s
->q_failed
&& s
->failed
< 2) {
3796 /* Q is not failed, and we didn't use it to generate
3797 * anything, so it makes sense to check it
3799 if (sh
->check_state
== check_state_run
)
3800 sh
->check_state
= check_state_run_pq
;
3802 sh
->check_state
= check_state_run_q
;
3805 /* discard potentially stale zero_sum_result */
3806 sh
->ops
.zero_sum_result
= 0;
3808 if (sh
->check_state
== check_state_run
) {
3809 /* async_xor_zero_sum destroys the contents of P */
3810 clear_bit(R5_UPTODATE
, &sh
->dev
[pd_idx
].flags
);
3813 if (sh
->check_state
>= check_state_run
&&
3814 sh
->check_state
<= check_state_run_pq
) {
3815 /* async_syndrome_zero_sum preserves P and Q, so
3816 * no need to mark them !uptodate here
3818 set_bit(STRIPE_OP_CHECK
, &s
->ops_request
);
3822 /* we have 2-disk failure */
3823 BUG_ON(s
->failed
!= 2);
3825 case check_state_compute_result
:
3826 sh
->check_state
= check_state_idle
;
3828 /* check that a write has not made the stripe insync */
3829 if (test_bit(STRIPE_INSYNC
, &sh
->state
))
3832 /* now write out any block on a failed drive,
3833 * or P or Q if they were recomputed
3835 BUG_ON(s
->uptodate
< disks
- 1); /* We don't need Q to recover */
3836 if (s
->failed
== 2) {
3837 dev
= &sh
->dev
[s
->failed_num
[1]];
3839 set_bit(R5_LOCKED
, &dev
->flags
);
3840 set_bit(R5_Wantwrite
, &dev
->flags
);
3842 if (s
->failed
>= 1) {
3843 dev
= &sh
->dev
[s
->failed_num
[0]];
3845 set_bit(R5_LOCKED
, &dev
->flags
);
3846 set_bit(R5_Wantwrite
, &dev
->flags
);
3848 if (sh
->ops
.zero_sum_result
& SUM_CHECK_P_RESULT
) {
3849 dev
= &sh
->dev
[pd_idx
];
3851 set_bit(R5_LOCKED
, &dev
->flags
);
3852 set_bit(R5_Wantwrite
, &dev
->flags
);
3854 if (sh
->ops
.zero_sum_result
& SUM_CHECK_Q_RESULT
) {
3855 dev
= &sh
->dev
[qd_idx
];
3857 set_bit(R5_LOCKED
, &dev
->flags
);
3858 set_bit(R5_Wantwrite
, &dev
->flags
);
3860 clear_bit(STRIPE_DEGRADED
, &sh
->state
);
3862 set_bit(STRIPE_INSYNC
, &sh
->state
);
3864 case check_state_run
:
3865 case check_state_run_q
:
3866 case check_state_run_pq
:
3867 break; /* we will be called again upon completion */
3868 case check_state_check_result
:
3869 sh
->check_state
= check_state_idle
;
3871 /* handle a successful check operation, if parity is correct
3872 * we are done. Otherwise update the mismatch count and repair
3873 * parity if !MD_RECOVERY_CHECK
3875 if (sh
->ops
.zero_sum_result
== 0) {
3876 /* both parities are correct */
3878 set_bit(STRIPE_INSYNC
, &sh
->state
);
3880 /* in contrast to the raid5 case we can validate
3881 * parity, but still have a failure to write
3884 sh
->check_state
= check_state_compute_result
;
3885 /* Returning at this point means that we may go
3886 * off and bring p and/or q uptodate again so
3887 * we make sure to check zero_sum_result again
3888 * to verify if p or q need writeback
3892 atomic64_add(STRIPE_SECTORS
, &conf
->mddev
->resync_mismatches
);
3893 if (test_bit(MD_RECOVERY_CHECK
, &conf
->mddev
->recovery
))
3894 /* don't try to repair!! */
3895 set_bit(STRIPE_INSYNC
, &sh
->state
);
3897 int *target
= &sh
->ops
.target
;
3899 sh
->ops
.target
= -1;
3900 sh
->ops
.target2
= -1;
3901 sh
->check_state
= check_state_compute_run
;
3902 set_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
3903 set_bit(STRIPE_OP_COMPUTE_BLK
, &s
->ops_request
);
3904 if (sh
->ops
.zero_sum_result
& SUM_CHECK_P_RESULT
) {
3905 set_bit(R5_Wantcompute
,
3906 &sh
->dev
[pd_idx
].flags
);
3908 target
= &sh
->ops
.target2
;
3911 if (sh
->ops
.zero_sum_result
& SUM_CHECK_Q_RESULT
) {
3912 set_bit(R5_Wantcompute
,
3913 &sh
->dev
[qd_idx
].flags
);
3920 case check_state_compute_run
:
3923 printk(KERN_ERR
"%s: unknown check_state: %d sector: %llu\n",
3924 __func__
, sh
->check_state
,
3925 (unsigned long long) sh
->sector
);
3930 static void handle_stripe_expansion(struct r5conf
*conf
, struct stripe_head
*sh
)
3934 /* We have read all the blocks in this stripe and now we need to
3935 * copy some of them into a target stripe for expand.
3937 struct dma_async_tx_descriptor
*tx
= NULL
;
3938 BUG_ON(sh
->batch_head
);
3939 clear_bit(STRIPE_EXPAND_SOURCE
, &sh
->state
);
3940 for (i
= 0; i
< sh
->disks
; i
++)
3941 if (i
!= sh
->pd_idx
&& i
!= sh
->qd_idx
) {
3943 struct stripe_head
*sh2
;
3944 struct async_submit_ctl submit
;
3946 sector_t bn
= compute_blocknr(sh
, i
, 1);
3947 sector_t s
= raid5_compute_sector(conf
, bn
, 0,
3949 sh2
= get_active_stripe(conf
, s
, 0, 1, 1);
3951 /* so far only the early blocks of this stripe
3952 * have been requested. When later blocks
3953 * get requested, we will try again
3956 if (!test_bit(STRIPE_EXPANDING
, &sh2
->state
) ||
3957 test_bit(R5_Expanded
, &sh2
->dev
[dd_idx
].flags
)) {
3958 /* must have already done this block */
3959 release_stripe(sh2
);
3963 /* place all the copies on one channel */
3964 init_async_submit(&submit
, 0, tx
, NULL
, NULL
, NULL
);
3965 tx
= async_memcpy(sh2
->dev
[dd_idx
].page
,
3966 sh
->dev
[i
].page
, 0, 0, STRIPE_SIZE
,
3969 set_bit(R5_Expanded
, &sh2
->dev
[dd_idx
].flags
);
3970 set_bit(R5_UPTODATE
, &sh2
->dev
[dd_idx
].flags
);
3971 for (j
= 0; j
< conf
->raid_disks
; j
++)
3972 if (j
!= sh2
->pd_idx
&&
3974 !test_bit(R5_Expanded
, &sh2
->dev
[j
].flags
))
3976 if (j
== conf
->raid_disks
) {
3977 set_bit(STRIPE_EXPAND_READY
, &sh2
->state
);
3978 set_bit(STRIPE_HANDLE
, &sh2
->state
);
3980 release_stripe(sh2
);
3983 /* done submitting copies, wait for them to complete */
3984 async_tx_quiesce(&tx
);
3988 * handle_stripe - do things to a stripe.
3990 * We lock the stripe by setting STRIPE_ACTIVE and then examine the
3991 * state of various bits to see what needs to be done.
3993 * return some read requests which now have data
3994 * return some write requests which are safely on storage
3995 * schedule a read on some buffers
3996 * schedule a write of some buffers
3997 * return confirmation of parity correctness
4001 static void analyse_stripe(struct stripe_head
*sh
, struct stripe_head_state
*s
)
4003 struct r5conf
*conf
= sh
->raid_conf
;
4004 int disks
= sh
->disks
;
4007 int do_recovery
= 0;
4009 memset(s
, 0, sizeof(*s
));
4011 s
->expanding
= test_bit(STRIPE_EXPAND_SOURCE
, &sh
->state
) && !sh
->batch_head
;
4012 s
->expanded
= test_bit(STRIPE_EXPAND_READY
, &sh
->state
) && !sh
->batch_head
;
4013 s
->failed_num
[0] = -1;
4014 s
->failed_num
[1] = -1;
4016 /* Now to look around and see what can be done */
4018 for (i
=disks
; i
--; ) {
4019 struct md_rdev
*rdev
;
4026 pr_debug("check %d: state 0x%lx read %p write %p written %p\n",
4028 dev
->toread
, dev
->towrite
, dev
->written
);
4029 /* maybe we can reply to a read
4031 * new wantfill requests are only permitted while
4032 * ops_complete_biofill is guaranteed to be inactive
4034 if (test_bit(R5_UPTODATE
, &dev
->flags
) && dev
->toread
&&
4035 !test_bit(STRIPE_BIOFILL_RUN
, &sh
->state
))
4036 set_bit(R5_Wantfill
, &dev
->flags
);
4038 /* now count some things */
4039 if (test_bit(R5_LOCKED
, &dev
->flags
))
4041 if (test_bit(R5_UPTODATE
, &dev
->flags
))
4043 if (test_bit(R5_Wantcompute
, &dev
->flags
)) {
4045 BUG_ON(s
->compute
> 2);
4048 if (test_bit(R5_Wantfill
, &dev
->flags
))
4050 else if (dev
->toread
)
4054 if (!test_bit(R5_OVERWRITE
, &dev
->flags
))
4059 /* Prefer to use the replacement for reads, but only
4060 * if it is recovered enough and has no bad blocks.
4062 rdev
= rcu_dereference(conf
->disks
[i
].replacement
);
4063 if (rdev
&& !test_bit(Faulty
, &rdev
->flags
) &&
4064 rdev
->recovery_offset
>= sh
->sector
+ STRIPE_SECTORS
&&
4065 !is_badblock(rdev
, sh
->sector
, STRIPE_SECTORS
,
4066 &first_bad
, &bad_sectors
))
4067 set_bit(R5_ReadRepl
, &dev
->flags
);
4069 if (rdev
&& !test_bit(Faulty
, &rdev
->flags
))
4070 set_bit(R5_NeedReplace
, &dev
->flags
);
4072 clear_bit(R5_NeedReplace
, &dev
->flags
);
4073 rdev
= rcu_dereference(conf
->disks
[i
].rdev
);
4074 clear_bit(R5_ReadRepl
, &dev
->flags
);
4076 if (rdev
&& test_bit(Faulty
, &rdev
->flags
))
4079 is_bad
= is_badblock(rdev
, sh
->sector
, STRIPE_SECTORS
,
4080 &first_bad
, &bad_sectors
);
4081 if (s
->blocked_rdev
== NULL
4082 && (test_bit(Blocked
, &rdev
->flags
)
4085 set_bit(BlockedBadBlocks
,
4087 s
->blocked_rdev
= rdev
;
4088 atomic_inc(&rdev
->nr_pending
);
4091 clear_bit(R5_Insync
, &dev
->flags
);
4095 /* also not in-sync */
4096 if (!test_bit(WriteErrorSeen
, &rdev
->flags
) &&
4097 test_bit(R5_UPTODATE
, &dev
->flags
)) {
4098 /* treat as in-sync, but with a read error
4099 * which we can now try to correct
4101 set_bit(R5_Insync
, &dev
->flags
);
4102 set_bit(R5_ReadError
, &dev
->flags
);
4104 } else if (test_bit(In_sync
, &rdev
->flags
))
4105 set_bit(R5_Insync
, &dev
->flags
);
4106 else if (sh
->sector
+ STRIPE_SECTORS
<= rdev
->recovery_offset
)
4107 /* in sync if before recovery_offset */
4108 set_bit(R5_Insync
, &dev
->flags
);
4109 else if (test_bit(R5_UPTODATE
, &dev
->flags
) &&
4110 test_bit(R5_Expanded
, &dev
->flags
))
4111 /* If we've reshaped into here, we assume it is Insync.
4112 * We will shortly update recovery_offset to make
4115 set_bit(R5_Insync
, &dev
->flags
);
4117 if (test_bit(R5_WriteError
, &dev
->flags
)) {
4118 /* This flag does not apply to '.replacement'
4119 * only to .rdev, so make sure to check that*/
4120 struct md_rdev
*rdev2
= rcu_dereference(
4121 conf
->disks
[i
].rdev
);
4123 clear_bit(R5_Insync
, &dev
->flags
);
4124 if (rdev2
&& !test_bit(Faulty
, &rdev2
->flags
)) {
4125 s
->handle_bad_blocks
= 1;
4126 atomic_inc(&rdev2
->nr_pending
);
4128 clear_bit(R5_WriteError
, &dev
->flags
);
4130 if (test_bit(R5_MadeGood
, &dev
->flags
)) {
4131 /* This flag does not apply to '.replacement'
4132 * only to .rdev, so make sure to check that*/
4133 struct md_rdev
*rdev2
= rcu_dereference(
4134 conf
->disks
[i
].rdev
);
4135 if (rdev2
&& !test_bit(Faulty
, &rdev2
->flags
)) {
4136 s
->handle_bad_blocks
= 1;
4137 atomic_inc(&rdev2
->nr_pending
);
4139 clear_bit(R5_MadeGood
, &dev
->flags
);
4141 if (test_bit(R5_MadeGoodRepl
, &dev
->flags
)) {
4142 struct md_rdev
*rdev2
= rcu_dereference(
4143 conf
->disks
[i
].replacement
);
4144 if (rdev2
&& !test_bit(Faulty
, &rdev2
->flags
)) {
4145 s
->handle_bad_blocks
= 1;
4146 atomic_inc(&rdev2
->nr_pending
);
4148 clear_bit(R5_MadeGoodRepl
, &dev
->flags
);
4150 if (!test_bit(R5_Insync
, &dev
->flags
)) {
4151 /* The ReadError flag will just be confusing now */
4152 clear_bit(R5_ReadError
, &dev
->flags
);
4153 clear_bit(R5_ReWrite
, &dev
->flags
);
4155 if (test_bit(R5_ReadError
, &dev
->flags
))
4156 clear_bit(R5_Insync
, &dev
->flags
);
4157 if (!test_bit(R5_Insync
, &dev
->flags
)) {
4159 s
->failed_num
[s
->failed
] = i
;
4161 if (rdev
&& !test_bit(Faulty
, &rdev
->flags
))
4165 if (test_bit(STRIPE_SYNCING
, &sh
->state
)) {
4166 /* If there is a failed device being replaced,
4167 * we must be recovering.
4168 * else if we are after recovery_cp, we must be syncing
4169 * else if MD_RECOVERY_REQUESTED is set, we also are syncing.
4170 * else we can only be replacing
4171 * sync and recovery both need to read all devices, and so
4172 * use the same flag.
4175 sh
->sector
>= conf
->mddev
->recovery_cp
||
4176 test_bit(MD_RECOVERY_REQUESTED
, &(conf
->mddev
->recovery
)))
4184 static int clear_batch_ready(struct stripe_head
*sh
)
4186 /* Return '1' if this is a member of batch, or
4187 * '0' if it is a lone stripe or a head which can now be
4190 struct stripe_head
*tmp
;
4191 if (!test_and_clear_bit(STRIPE_BATCH_READY
, &sh
->state
))
4192 return (sh
->batch_head
&& sh
->batch_head
!= sh
);
4193 spin_lock(&sh
->stripe_lock
);
4194 if (!sh
->batch_head
) {
4195 spin_unlock(&sh
->stripe_lock
);
4200 * this stripe could be added to a batch list before we check
4201 * BATCH_READY, skips it
4203 if (sh
->batch_head
!= sh
) {
4204 spin_unlock(&sh
->stripe_lock
);
4207 spin_lock(&sh
->batch_lock
);
4208 list_for_each_entry(tmp
, &sh
->batch_list
, batch_list
)
4209 clear_bit(STRIPE_BATCH_READY
, &tmp
->state
);
4210 spin_unlock(&sh
->batch_lock
);
4211 spin_unlock(&sh
->stripe_lock
);
4214 * BATCH_READY is cleared, no new stripes can be added.
4215 * batch_list can be accessed without lock
4220 static void break_stripe_batch_list(struct stripe_head
*head_sh
,
4221 unsigned long handle_flags
)
4223 struct stripe_head
*sh
, *next
;
4227 list_for_each_entry_safe(sh
, next
, &head_sh
->batch_list
, batch_list
) {
4229 list_del_init(&sh
->batch_list
);
4231 WARN_ON_ONCE(sh
->state
& ((1 << STRIPE_ACTIVE
) |
4232 (1 << STRIPE_SYNCING
) |
4233 (1 << STRIPE_REPLACED
) |
4234 (1 << STRIPE_PREREAD_ACTIVE
) |
4235 (1 << STRIPE_DELAYED
) |
4236 (1 << STRIPE_BIT_DELAY
) |
4237 (1 << STRIPE_FULL_WRITE
) |
4238 (1 << STRIPE_BIOFILL_RUN
) |
4239 (1 << STRIPE_COMPUTE_RUN
) |
4240 (1 << STRIPE_OPS_REQ_PENDING
) |
4241 (1 << STRIPE_DISCARD
) |
4242 (1 << STRIPE_BATCH_READY
) |
4243 (1 << STRIPE_BATCH_ERR
) |
4244 (1 << STRIPE_BITMAP_PENDING
)));
4245 WARN_ON_ONCE(head_sh
->state
& ((1 << STRIPE_DISCARD
) |
4246 (1 << STRIPE_REPLACED
)));
4248 set_mask_bits(&sh
->state
, ~(STRIPE_EXPAND_SYNC_FLAGS
|
4249 (1 << STRIPE_DEGRADED
)),
4250 head_sh
->state
& (1 << STRIPE_INSYNC
));
4252 sh
->check_state
= head_sh
->check_state
;
4253 sh
->reconstruct_state
= head_sh
->reconstruct_state
;
4254 for (i
= 0; i
< sh
->disks
; i
++) {
4255 if (test_and_clear_bit(R5_Overlap
, &sh
->dev
[i
].flags
))
4257 sh
->dev
[i
].flags
= head_sh
->dev
[i
].flags
&
4258 (~((1 << R5_WriteError
) | (1 << R5_Overlap
)));
4260 spin_lock_irq(&sh
->stripe_lock
);
4261 sh
->batch_head
= NULL
;
4262 spin_unlock_irq(&sh
->stripe_lock
);
4263 if (handle_flags
== 0 ||
4264 sh
->state
& handle_flags
)
4265 set_bit(STRIPE_HANDLE
, &sh
->state
);
4268 spin_lock_irq(&head_sh
->stripe_lock
);
4269 head_sh
->batch_head
= NULL
;
4270 spin_unlock_irq(&head_sh
->stripe_lock
);
4271 for (i
= 0; i
< head_sh
->disks
; i
++)
4272 if (test_and_clear_bit(R5_Overlap
, &head_sh
->dev
[i
].flags
))
4274 if (head_sh
->state
& handle_flags
)
4275 set_bit(STRIPE_HANDLE
, &head_sh
->state
);
4278 wake_up(&head_sh
->raid_conf
->wait_for_overlap
);
4281 static void handle_stripe(struct stripe_head
*sh
)
4283 struct stripe_head_state s
;
4284 struct r5conf
*conf
= sh
->raid_conf
;
4287 int disks
= sh
->disks
;
4288 struct r5dev
*pdev
, *qdev
;
4290 clear_bit(STRIPE_HANDLE
, &sh
->state
);
4291 if (test_and_set_bit_lock(STRIPE_ACTIVE
, &sh
->state
)) {
4292 /* already being handled, ensure it gets handled
4293 * again when current action finishes */
4294 set_bit(STRIPE_HANDLE
, &sh
->state
);
4298 if (clear_batch_ready(sh
) ) {
4299 clear_bit_unlock(STRIPE_ACTIVE
, &sh
->state
);
4303 if (test_and_clear_bit(STRIPE_BATCH_ERR
, &sh
->state
))
4304 break_stripe_batch_list(sh
, 0);
4306 if (test_bit(STRIPE_SYNC_REQUESTED
, &sh
->state
) && !sh
->batch_head
) {
4307 spin_lock(&sh
->stripe_lock
);
4308 /* Cannot process 'sync' concurrently with 'discard' */
4309 if (!test_bit(STRIPE_DISCARD
, &sh
->state
) &&
4310 test_and_clear_bit(STRIPE_SYNC_REQUESTED
, &sh
->state
)) {
4311 set_bit(STRIPE_SYNCING
, &sh
->state
);
4312 clear_bit(STRIPE_INSYNC
, &sh
->state
);
4313 clear_bit(STRIPE_REPLACED
, &sh
->state
);
4315 spin_unlock(&sh
->stripe_lock
);
4317 clear_bit(STRIPE_DELAYED
, &sh
->state
);
4319 pr_debug("handling stripe %llu, state=%#lx cnt=%d, "
4320 "pd_idx=%d, qd_idx=%d\n, check:%d, reconstruct:%d\n",
4321 (unsigned long long)sh
->sector
, sh
->state
,
4322 atomic_read(&sh
->count
), sh
->pd_idx
, sh
->qd_idx
,
4323 sh
->check_state
, sh
->reconstruct_state
);
4325 analyse_stripe(sh
, &s
);
4327 if (s
.handle_bad_blocks
) {
4328 set_bit(STRIPE_HANDLE
, &sh
->state
);
4332 if (unlikely(s
.blocked_rdev
)) {
4333 if (s
.syncing
|| s
.expanding
|| s
.expanded
||
4334 s
.replacing
|| s
.to_write
|| s
.written
) {
4335 set_bit(STRIPE_HANDLE
, &sh
->state
);
4338 /* There is nothing for the blocked_rdev to block */
4339 rdev_dec_pending(s
.blocked_rdev
, conf
->mddev
);
4340 s
.blocked_rdev
= NULL
;
4343 if (s
.to_fill
&& !test_bit(STRIPE_BIOFILL_RUN
, &sh
->state
)) {
4344 set_bit(STRIPE_OP_BIOFILL
, &s
.ops_request
);
4345 set_bit(STRIPE_BIOFILL_RUN
, &sh
->state
);
4348 pr_debug("locked=%d uptodate=%d to_read=%d"
4349 " to_write=%d failed=%d failed_num=%d,%d\n",
4350 s
.locked
, s
.uptodate
, s
.to_read
, s
.to_write
, s
.failed
,
4351 s
.failed_num
[0], s
.failed_num
[1]);
4352 /* check if the array has lost more than max_degraded devices and,
4353 * if so, some requests might need to be failed.
4355 if (s
.failed
> conf
->max_degraded
) {
4356 sh
->check_state
= 0;
4357 sh
->reconstruct_state
= 0;
4358 break_stripe_batch_list(sh
, 0);
4359 if (s
.to_read
+s
.to_write
+s
.written
)
4360 handle_failed_stripe(conf
, sh
, &s
, disks
, &s
.return_bi
);
4361 if (s
.syncing
+ s
.replacing
)
4362 handle_failed_sync(conf
, sh
, &s
);
4365 /* Now we check to see if any write operations have recently
4369 if (sh
->reconstruct_state
== reconstruct_state_prexor_drain_result
)
4371 if (sh
->reconstruct_state
== reconstruct_state_drain_result
||
4372 sh
->reconstruct_state
== reconstruct_state_prexor_drain_result
) {
4373 sh
->reconstruct_state
= reconstruct_state_idle
;
4375 /* All the 'written' buffers and the parity block are ready to
4376 * be written back to disk
4378 BUG_ON(!test_bit(R5_UPTODATE
, &sh
->dev
[sh
->pd_idx
].flags
) &&
4379 !test_bit(R5_Discard
, &sh
->dev
[sh
->pd_idx
].flags
));
4380 BUG_ON(sh
->qd_idx
>= 0 &&
4381 !test_bit(R5_UPTODATE
, &sh
->dev
[sh
->qd_idx
].flags
) &&
4382 !test_bit(R5_Discard
, &sh
->dev
[sh
->qd_idx
].flags
));
4383 for (i
= disks
; i
--; ) {
4384 struct r5dev
*dev
= &sh
->dev
[i
];
4385 if (test_bit(R5_LOCKED
, &dev
->flags
) &&
4386 (i
== sh
->pd_idx
|| i
== sh
->qd_idx
||
4388 pr_debug("Writing block %d\n", i
);
4389 set_bit(R5_Wantwrite
, &dev
->flags
);
4394 if (!test_bit(R5_Insync
, &dev
->flags
) ||
4395 ((i
== sh
->pd_idx
|| i
== sh
->qd_idx
) &&
4397 set_bit(STRIPE_INSYNC
, &sh
->state
);
4400 if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
4401 s
.dec_preread_active
= 1;
4405 * might be able to return some write requests if the parity blocks
4406 * are safe, or on a failed drive
4408 pdev
= &sh
->dev
[sh
->pd_idx
];
4409 s
.p_failed
= (s
.failed
>= 1 && s
.failed_num
[0] == sh
->pd_idx
)
4410 || (s
.failed
>= 2 && s
.failed_num
[1] == sh
->pd_idx
);
4411 qdev
= &sh
->dev
[sh
->qd_idx
];
4412 s
.q_failed
= (s
.failed
>= 1 && s
.failed_num
[0] == sh
->qd_idx
)
4413 || (s
.failed
>= 2 && s
.failed_num
[1] == sh
->qd_idx
)
4417 (s
.p_failed
|| ((test_bit(R5_Insync
, &pdev
->flags
)
4418 && !test_bit(R5_LOCKED
, &pdev
->flags
)
4419 && (test_bit(R5_UPTODATE
, &pdev
->flags
) ||
4420 test_bit(R5_Discard
, &pdev
->flags
))))) &&
4421 (s
.q_failed
|| ((test_bit(R5_Insync
, &qdev
->flags
)
4422 && !test_bit(R5_LOCKED
, &qdev
->flags
)
4423 && (test_bit(R5_UPTODATE
, &qdev
->flags
) ||
4424 test_bit(R5_Discard
, &qdev
->flags
))))))
4425 handle_stripe_clean_event(conf
, sh
, disks
, &s
.return_bi
);
4427 /* Now we might consider reading some blocks, either to check/generate
4428 * parity, or to satisfy requests
4429 * or to load a block that is being partially written.
4431 if (s
.to_read
|| s
.non_overwrite
4432 || (conf
->level
== 6 && s
.to_write
&& s
.failed
)
4433 || (s
.syncing
&& (s
.uptodate
+ s
.compute
< disks
))
4436 handle_stripe_fill(sh
, &s
, disks
);
4438 /* Now to consider new write requests and what else, if anything
4439 * should be read. We do not handle new writes when:
4440 * 1/ A 'write' operation (copy+xor) is already in flight.
4441 * 2/ A 'check' operation is in flight, as it may clobber the parity
4444 if (s
.to_write
&& !sh
->reconstruct_state
&& !sh
->check_state
)
4445 handle_stripe_dirtying(conf
, sh
, &s
, disks
);
4447 /* maybe we need to check and possibly fix the parity for this stripe
4448 * Any reads will already have been scheduled, so we just see if enough
4449 * data is available. The parity check is held off while parity
4450 * dependent operations are in flight.
4452 if (sh
->check_state
||
4453 (s
.syncing
&& s
.locked
== 0 &&
4454 !test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
) &&
4455 !test_bit(STRIPE_INSYNC
, &sh
->state
))) {
4456 if (conf
->level
== 6)
4457 handle_parity_checks6(conf
, sh
, &s
, disks
);
4459 handle_parity_checks5(conf
, sh
, &s
, disks
);
4462 if ((s
.replacing
|| s
.syncing
) && s
.locked
== 0
4463 && !test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
)
4464 && !test_bit(STRIPE_REPLACED
, &sh
->state
)) {
4465 /* Write out to replacement devices where possible */
4466 for (i
= 0; i
< conf
->raid_disks
; i
++)
4467 if (test_bit(R5_NeedReplace
, &sh
->dev
[i
].flags
)) {
4468 WARN_ON(!test_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
));
4469 set_bit(R5_WantReplace
, &sh
->dev
[i
].flags
);
4470 set_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
4474 set_bit(STRIPE_INSYNC
, &sh
->state
);
4475 set_bit(STRIPE_REPLACED
, &sh
->state
);
4477 if ((s
.syncing
|| s
.replacing
) && s
.locked
== 0 &&
4478 !test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
) &&
4479 test_bit(STRIPE_INSYNC
, &sh
->state
)) {
4480 md_done_sync(conf
->mddev
, STRIPE_SECTORS
, 1);
4481 clear_bit(STRIPE_SYNCING
, &sh
->state
);
4482 if (test_and_clear_bit(R5_Overlap
, &sh
->dev
[sh
->pd_idx
].flags
))
4483 wake_up(&conf
->wait_for_overlap
);
4486 /* If the failed drives are just a ReadError, then we might need
4487 * to progress the repair/check process
4489 if (s
.failed
<= conf
->max_degraded
&& !conf
->mddev
->ro
)
4490 for (i
= 0; i
< s
.failed
; i
++) {
4491 struct r5dev
*dev
= &sh
->dev
[s
.failed_num
[i
]];
4492 if (test_bit(R5_ReadError
, &dev
->flags
)
4493 && !test_bit(R5_LOCKED
, &dev
->flags
)
4494 && test_bit(R5_UPTODATE
, &dev
->flags
)
4496 if (!test_bit(R5_ReWrite
, &dev
->flags
)) {
4497 set_bit(R5_Wantwrite
, &dev
->flags
);
4498 set_bit(R5_ReWrite
, &dev
->flags
);
4499 set_bit(R5_LOCKED
, &dev
->flags
);
4502 /* let's read it back */
4503 set_bit(R5_Wantread
, &dev
->flags
);
4504 set_bit(R5_LOCKED
, &dev
->flags
);
4510 /* Finish reconstruct operations initiated by the expansion process */
4511 if (sh
->reconstruct_state
== reconstruct_state_result
) {
4512 struct stripe_head
*sh_src
4513 = get_active_stripe(conf
, sh
->sector
, 1, 1, 1);
4514 if (sh_src
&& test_bit(STRIPE_EXPAND_SOURCE
, &sh_src
->state
)) {
4515 /* sh cannot be written until sh_src has been read.
4516 * so arrange for sh to be delayed a little
4518 set_bit(STRIPE_DELAYED
, &sh
->state
);
4519 set_bit(STRIPE_HANDLE
, &sh
->state
);
4520 if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE
,
4522 atomic_inc(&conf
->preread_active_stripes
);
4523 release_stripe(sh_src
);
4527 release_stripe(sh_src
);
4529 sh
->reconstruct_state
= reconstruct_state_idle
;
4530 clear_bit(STRIPE_EXPANDING
, &sh
->state
);
4531 for (i
= conf
->raid_disks
; i
--; ) {
4532 set_bit(R5_Wantwrite
, &sh
->dev
[i
].flags
);
4533 set_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
4538 if (s
.expanded
&& test_bit(STRIPE_EXPANDING
, &sh
->state
) &&
4539 !sh
->reconstruct_state
) {
4540 /* Need to write out all blocks after computing parity */
4541 sh
->disks
= conf
->raid_disks
;
4542 stripe_set_idx(sh
->sector
, conf
, 0, sh
);
4543 schedule_reconstruction(sh
, &s
, 1, 1);
4544 } else if (s
.expanded
&& !sh
->reconstruct_state
&& s
.locked
== 0) {
4545 clear_bit(STRIPE_EXPAND_READY
, &sh
->state
);
4546 atomic_dec(&conf
->reshape_stripes
);
4547 wake_up(&conf
->wait_for_overlap
);
4548 md_done_sync(conf
->mddev
, STRIPE_SECTORS
, 1);
4551 if (s
.expanding
&& s
.locked
== 0 &&
4552 !test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
))
4553 handle_stripe_expansion(conf
, sh
);
4556 /* wait for this device to become unblocked */
4557 if (unlikely(s
.blocked_rdev
)) {
4558 if (conf
->mddev
->external
)
4559 md_wait_for_blocked_rdev(s
.blocked_rdev
,
4562 /* Internal metadata will immediately
4563 * be written by raid5d, so we don't
4564 * need to wait here.
4566 rdev_dec_pending(s
.blocked_rdev
,
4570 if (s
.handle_bad_blocks
)
4571 for (i
= disks
; i
--; ) {
4572 struct md_rdev
*rdev
;
4573 struct r5dev
*dev
= &sh
->dev
[i
];
4574 if (test_and_clear_bit(R5_WriteError
, &dev
->flags
)) {
4575 /* We own a safe reference to the rdev */
4576 rdev
= conf
->disks
[i
].rdev
;
4577 if (!rdev_set_badblocks(rdev
, sh
->sector
,
4579 md_error(conf
->mddev
, rdev
);
4580 rdev_dec_pending(rdev
, conf
->mddev
);
4582 if (test_and_clear_bit(R5_MadeGood
, &dev
->flags
)) {
4583 rdev
= conf
->disks
[i
].rdev
;
4584 rdev_clear_badblocks(rdev
, sh
->sector
,
4586 rdev_dec_pending(rdev
, conf
->mddev
);
4588 if (test_and_clear_bit(R5_MadeGoodRepl
, &dev
->flags
)) {
4589 rdev
= conf
->disks
[i
].replacement
;
4591 /* rdev have been moved down */
4592 rdev
= conf
->disks
[i
].rdev
;
4593 rdev_clear_badblocks(rdev
, sh
->sector
,
4595 rdev_dec_pending(rdev
, conf
->mddev
);
4600 raid_run_ops(sh
, s
.ops_request
);
4604 if (s
.dec_preread_active
) {
4605 /* We delay this until after ops_run_io so that if make_request
4606 * is waiting on a flush, it won't continue until the writes
4607 * have actually been submitted.
4609 atomic_dec(&conf
->preread_active_stripes
);
4610 if (atomic_read(&conf
->preread_active_stripes
) <
4612 md_wakeup_thread(conf
->mddev
->thread
);
4615 return_io(s
.return_bi
);
4617 clear_bit_unlock(STRIPE_ACTIVE
, &sh
->state
);
4620 static void raid5_activate_delayed(struct r5conf
*conf
)
4622 if (atomic_read(&conf
->preread_active_stripes
) < IO_THRESHOLD
) {
4623 while (!list_empty(&conf
->delayed_list
)) {
4624 struct list_head
*l
= conf
->delayed_list
.next
;
4625 struct stripe_head
*sh
;
4626 sh
= list_entry(l
, struct stripe_head
, lru
);
4628 clear_bit(STRIPE_DELAYED
, &sh
->state
);
4629 if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
4630 atomic_inc(&conf
->preread_active_stripes
);
4631 list_add_tail(&sh
->lru
, &conf
->hold_list
);
4632 raid5_wakeup_stripe_thread(sh
);
4637 static void activate_bit_delay(struct r5conf
*conf
,
4638 struct list_head
*temp_inactive_list
)
4640 /* device_lock is held */
4641 struct list_head head
;
4642 list_add(&head
, &conf
->bitmap_list
);
4643 list_del_init(&conf
->bitmap_list
);
4644 while (!list_empty(&head
)) {
4645 struct stripe_head
*sh
= list_entry(head
.next
, struct stripe_head
, lru
);
4647 list_del_init(&sh
->lru
);
4648 atomic_inc(&sh
->count
);
4649 hash
= sh
->hash_lock_index
;
4650 __release_stripe(conf
, sh
, &temp_inactive_list
[hash
]);
4654 static int raid5_congested(struct mddev
*mddev
, int bits
)
4656 struct r5conf
*conf
= mddev
->private;
4658 /* No difference between reads and writes. Just check
4659 * how busy the stripe_cache is
4662 if (test_bit(R5_INACTIVE_BLOCKED
, &conf
->cache_state
))
4666 if (atomic_read(&conf
->empty_inactive_list_nr
))
4672 /* We want read requests to align with chunks where possible,
4673 * but write requests don't need to.
4675 static int raid5_mergeable_bvec(struct mddev
*mddev
,
4676 struct bvec_merge_data
*bvm
,
4677 struct bio_vec
*biovec
)
4679 sector_t sector
= bvm
->bi_sector
+ get_start_sect(bvm
->bi_bdev
);
4681 unsigned int chunk_sectors
= mddev
->chunk_sectors
;
4682 unsigned int bio_sectors
= bvm
->bi_size
>> 9;
4685 * always allow writes to be mergeable, read as well if array
4686 * is degraded as we'll go through stripe cache anyway.
4688 if ((bvm
->bi_rw
& 1) == WRITE
|| mddev
->degraded
)
4689 return biovec
->bv_len
;
4691 if (mddev
->new_chunk_sectors
< mddev
->chunk_sectors
)
4692 chunk_sectors
= mddev
->new_chunk_sectors
;
4693 max
= (chunk_sectors
- ((sector
& (chunk_sectors
- 1)) + bio_sectors
)) << 9;
4694 if (max
< 0) max
= 0;
4695 if (max
<= biovec
->bv_len
&& bio_sectors
== 0)
4696 return biovec
->bv_len
;
4701 static int in_chunk_boundary(struct mddev
*mddev
, struct bio
*bio
)
4703 sector_t sector
= bio
->bi_iter
.bi_sector
+ get_start_sect(bio
->bi_bdev
);
4704 unsigned int chunk_sectors
= mddev
->chunk_sectors
;
4705 unsigned int bio_sectors
= bio_sectors(bio
);
4707 if (mddev
->new_chunk_sectors
< mddev
->chunk_sectors
)
4708 chunk_sectors
= mddev
->new_chunk_sectors
;
4709 return chunk_sectors
>=
4710 ((sector
& (chunk_sectors
- 1)) + bio_sectors
);
4714 * add bio to the retry LIFO ( in O(1) ... we are in interrupt )
4715 * later sampled by raid5d.
4717 static void add_bio_to_retry(struct bio
*bi
,struct r5conf
*conf
)
4719 unsigned long flags
;
4721 spin_lock_irqsave(&conf
->device_lock
, flags
);
4723 bi
->bi_next
= conf
->retry_read_aligned_list
;
4724 conf
->retry_read_aligned_list
= bi
;
4726 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
4727 md_wakeup_thread(conf
->mddev
->thread
);
4730 static struct bio
*remove_bio_from_retry(struct r5conf
*conf
)
4734 bi
= conf
->retry_read_aligned
;
4736 conf
->retry_read_aligned
= NULL
;
4739 bi
= conf
->retry_read_aligned_list
;
4741 conf
->retry_read_aligned_list
= bi
->bi_next
;
4744 * this sets the active strip count to 1 and the processed
4745 * strip count to zero (upper 8 bits)
4747 raid5_set_bi_stripes(bi
, 1); /* biased count of active stripes */
4754 * The "raid5_align_endio" should check if the read succeeded and if it
4755 * did, call bio_endio on the original bio (having bio_put the new bio
4757 * If the read failed..
4759 static void raid5_align_endio(struct bio
*bi
, int error
)
4761 struct bio
* raid_bi
= bi
->bi_private
;
4762 struct mddev
*mddev
;
4763 struct r5conf
*conf
;
4764 int uptodate
= test_bit(BIO_UPTODATE
, &bi
->bi_flags
);
4765 struct md_rdev
*rdev
;
4769 rdev
= (void*)raid_bi
->bi_next
;
4770 raid_bi
->bi_next
= NULL
;
4771 mddev
= rdev
->mddev
;
4772 conf
= mddev
->private;
4774 rdev_dec_pending(rdev
, conf
->mddev
);
4776 if (!error
&& uptodate
) {
4777 trace_block_bio_complete(bdev_get_queue(raid_bi
->bi_bdev
),
4779 bio_endio(raid_bi
, 0);
4780 if (atomic_dec_and_test(&conf
->active_aligned_reads
))
4781 wake_up(&conf
->wait_for_quiescent
);
4785 pr_debug("raid5_align_endio : io error...handing IO for a retry\n");
4787 add_bio_to_retry(raid_bi
, conf
);
4790 static int bio_fits_rdev(struct bio
*bi
)
4792 struct request_queue
*q
= bdev_get_queue(bi
->bi_bdev
);
4794 if (bio_sectors(bi
) > queue_max_sectors(q
))
4796 blk_recount_segments(q
, bi
);
4797 if (bi
->bi_phys_segments
> queue_max_segments(q
))
4800 if (q
->merge_bvec_fn
)
4801 /* it's too hard to apply the merge_bvec_fn at this stage,
4809 static int chunk_aligned_read(struct mddev
*mddev
, struct bio
* raid_bio
)
4811 struct r5conf
*conf
= mddev
->private;
4813 struct bio
* align_bi
;
4814 struct md_rdev
*rdev
;
4815 sector_t end_sector
;
4817 if (!in_chunk_boundary(mddev
, raid_bio
)) {
4818 pr_debug("chunk_aligned_read : non aligned\n");
4822 * use bio_clone_mddev to make a copy of the bio
4824 align_bi
= bio_clone_mddev(raid_bio
, GFP_NOIO
, mddev
);
4828 * set bi_end_io to a new function, and set bi_private to the
4831 align_bi
->bi_end_io
= raid5_align_endio
;
4832 align_bi
->bi_private
= raid_bio
;
4836 align_bi
->bi_iter
.bi_sector
=
4837 raid5_compute_sector(conf
, raid_bio
->bi_iter
.bi_sector
,
4840 end_sector
= bio_end_sector(align_bi
);
4842 rdev
= rcu_dereference(conf
->disks
[dd_idx
].replacement
);
4843 if (!rdev
|| test_bit(Faulty
, &rdev
->flags
) ||
4844 rdev
->recovery_offset
< end_sector
) {
4845 rdev
= rcu_dereference(conf
->disks
[dd_idx
].rdev
);
4847 (test_bit(Faulty
, &rdev
->flags
) ||
4848 !(test_bit(In_sync
, &rdev
->flags
) ||
4849 rdev
->recovery_offset
>= end_sector
)))
4856 atomic_inc(&rdev
->nr_pending
);
4858 raid_bio
->bi_next
= (void*)rdev
;
4859 align_bi
->bi_bdev
= rdev
->bdev
;
4860 __clear_bit(BIO_SEG_VALID
, &align_bi
->bi_flags
);
4862 if (!bio_fits_rdev(align_bi
) ||
4863 is_badblock(rdev
, align_bi
->bi_iter
.bi_sector
,
4864 bio_sectors(align_bi
),
4865 &first_bad
, &bad_sectors
)) {
4866 /* too big in some way, or has a known bad block */
4868 rdev_dec_pending(rdev
, mddev
);
4872 /* No reshape active, so we can trust rdev->data_offset */
4873 align_bi
->bi_iter
.bi_sector
+= rdev
->data_offset
;
4875 spin_lock_irq(&conf
->device_lock
);
4876 wait_event_lock_irq(conf
->wait_for_quiescent
,
4879 atomic_inc(&conf
->active_aligned_reads
);
4880 spin_unlock_irq(&conf
->device_lock
);
4883 trace_block_bio_remap(bdev_get_queue(align_bi
->bi_bdev
),
4884 align_bi
, disk_devt(mddev
->gendisk
),
4885 raid_bio
->bi_iter
.bi_sector
);
4886 generic_make_request(align_bi
);
4895 /* __get_priority_stripe - get the next stripe to process
4897 * Full stripe writes are allowed to pass preread active stripes up until
4898 * the bypass_threshold is exceeded. In general the bypass_count
4899 * increments when the handle_list is handled before the hold_list; however, it
4900 * will not be incremented when STRIPE_IO_STARTED is sampled set signifying a
4901 * stripe with in flight i/o. The bypass_count will be reset when the
4902 * head of the hold_list has changed, i.e. the head was promoted to the
4905 static struct stripe_head
*__get_priority_stripe(struct r5conf
*conf
, int group
)
4907 struct stripe_head
*sh
= NULL
, *tmp
;
4908 struct list_head
*handle_list
= NULL
;
4909 struct r5worker_group
*wg
= NULL
;
4911 if (conf
->worker_cnt_per_group
== 0) {
4912 handle_list
= &conf
->handle_list
;
4913 } else if (group
!= ANY_GROUP
) {
4914 handle_list
= &conf
->worker_groups
[group
].handle_list
;
4915 wg
= &conf
->worker_groups
[group
];
4918 for (i
= 0; i
< conf
->group_cnt
; i
++) {
4919 handle_list
= &conf
->worker_groups
[i
].handle_list
;
4920 wg
= &conf
->worker_groups
[i
];
4921 if (!list_empty(handle_list
))
4926 pr_debug("%s: handle: %s hold: %s full_writes: %d bypass_count: %d\n",
4928 list_empty(handle_list
) ? "empty" : "busy",
4929 list_empty(&conf
->hold_list
) ? "empty" : "busy",
4930 atomic_read(&conf
->pending_full_writes
), conf
->bypass_count
);
4932 if (!list_empty(handle_list
)) {
4933 sh
= list_entry(handle_list
->next
, typeof(*sh
), lru
);
4935 if (list_empty(&conf
->hold_list
))
4936 conf
->bypass_count
= 0;
4937 else if (!test_bit(STRIPE_IO_STARTED
, &sh
->state
)) {
4938 if (conf
->hold_list
.next
== conf
->last_hold
)
4939 conf
->bypass_count
++;
4941 conf
->last_hold
= conf
->hold_list
.next
;
4942 conf
->bypass_count
-= conf
->bypass_threshold
;
4943 if (conf
->bypass_count
< 0)
4944 conf
->bypass_count
= 0;
4947 } else if (!list_empty(&conf
->hold_list
) &&
4948 ((conf
->bypass_threshold
&&
4949 conf
->bypass_count
> conf
->bypass_threshold
) ||
4950 atomic_read(&conf
->pending_full_writes
) == 0)) {
4952 list_for_each_entry(tmp
, &conf
->hold_list
, lru
) {
4953 if (conf
->worker_cnt_per_group
== 0 ||
4954 group
== ANY_GROUP
||
4955 !cpu_online(tmp
->cpu
) ||
4956 cpu_to_group(tmp
->cpu
) == group
) {
4963 conf
->bypass_count
-= conf
->bypass_threshold
;
4964 if (conf
->bypass_count
< 0)
4965 conf
->bypass_count
= 0;
4977 list_del_init(&sh
->lru
);
4978 BUG_ON(atomic_inc_return(&sh
->count
) != 1);
4982 struct raid5_plug_cb
{
4983 struct blk_plug_cb cb
;
4984 struct list_head list
;
4985 struct list_head temp_inactive_list
[NR_STRIPE_HASH_LOCKS
];
4988 static void raid5_unplug(struct blk_plug_cb
*blk_cb
, bool from_schedule
)
4990 struct raid5_plug_cb
*cb
= container_of(
4991 blk_cb
, struct raid5_plug_cb
, cb
);
4992 struct stripe_head
*sh
;
4993 struct mddev
*mddev
= cb
->cb
.data
;
4994 struct r5conf
*conf
= mddev
->private;
4998 if (cb
->list
.next
&& !list_empty(&cb
->list
)) {
4999 spin_lock_irq(&conf
->device_lock
);
5000 while (!list_empty(&cb
->list
)) {
5001 sh
= list_first_entry(&cb
->list
, struct stripe_head
, lru
);
5002 list_del_init(&sh
->lru
);
5004 * avoid race release_stripe_plug() sees
5005 * STRIPE_ON_UNPLUG_LIST clear but the stripe
5006 * is still in our list
5008 smp_mb__before_atomic();
5009 clear_bit(STRIPE_ON_UNPLUG_LIST
, &sh
->state
);
5011 * STRIPE_ON_RELEASE_LIST could be set here. In that
5012 * case, the count is always > 1 here
5014 hash
= sh
->hash_lock_index
;
5015 __release_stripe(conf
, sh
, &cb
->temp_inactive_list
[hash
]);
5018 spin_unlock_irq(&conf
->device_lock
);
5020 release_inactive_stripe_list(conf
, cb
->temp_inactive_list
,
5021 NR_STRIPE_HASH_LOCKS
);
5023 trace_block_unplug(mddev
->queue
, cnt
, !from_schedule
);
5027 static void release_stripe_plug(struct mddev
*mddev
,
5028 struct stripe_head
*sh
)
5030 struct blk_plug_cb
*blk_cb
= blk_check_plugged(
5031 raid5_unplug
, mddev
,
5032 sizeof(struct raid5_plug_cb
));
5033 struct raid5_plug_cb
*cb
;
5040 cb
= container_of(blk_cb
, struct raid5_plug_cb
, cb
);
5042 if (cb
->list
.next
== NULL
) {
5044 INIT_LIST_HEAD(&cb
->list
);
5045 for (i
= 0; i
< NR_STRIPE_HASH_LOCKS
; i
++)
5046 INIT_LIST_HEAD(cb
->temp_inactive_list
+ i
);
5049 if (!test_and_set_bit(STRIPE_ON_UNPLUG_LIST
, &sh
->state
))
5050 list_add_tail(&sh
->lru
, &cb
->list
);
5055 static void make_discard_request(struct mddev
*mddev
, struct bio
*bi
)
5057 struct r5conf
*conf
= mddev
->private;
5058 sector_t logical_sector
, last_sector
;
5059 struct stripe_head
*sh
;
5063 if (mddev
->reshape_position
!= MaxSector
)
5064 /* Skip discard while reshape is happening */
5067 logical_sector
= bi
->bi_iter
.bi_sector
& ~((sector_t
)STRIPE_SECTORS
-1);
5068 last_sector
= bi
->bi_iter
.bi_sector
+ (bi
->bi_iter
.bi_size
>>9);
5071 bi
->bi_phys_segments
= 1; /* over-loaded to count active stripes */
5073 stripe_sectors
= conf
->chunk_sectors
*
5074 (conf
->raid_disks
- conf
->max_degraded
);
5075 logical_sector
= DIV_ROUND_UP_SECTOR_T(logical_sector
,
5077 sector_div(last_sector
, stripe_sectors
);
5079 logical_sector
*= conf
->chunk_sectors
;
5080 last_sector
*= conf
->chunk_sectors
;
5082 for (; logical_sector
< last_sector
;
5083 logical_sector
+= STRIPE_SECTORS
) {
5087 sh
= get_active_stripe(conf
, logical_sector
, 0, 0, 0);
5088 prepare_to_wait(&conf
->wait_for_overlap
, &w
,
5089 TASK_UNINTERRUPTIBLE
);
5090 set_bit(R5_Overlap
, &sh
->dev
[sh
->pd_idx
].flags
);
5091 if (test_bit(STRIPE_SYNCING
, &sh
->state
)) {
5096 clear_bit(R5_Overlap
, &sh
->dev
[sh
->pd_idx
].flags
);
5097 spin_lock_irq(&sh
->stripe_lock
);
5098 for (d
= 0; d
< conf
->raid_disks
; d
++) {
5099 if (d
== sh
->pd_idx
|| d
== sh
->qd_idx
)
5101 if (sh
->dev
[d
].towrite
|| sh
->dev
[d
].toread
) {
5102 set_bit(R5_Overlap
, &sh
->dev
[d
].flags
);
5103 spin_unlock_irq(&sh
->stripe_lock
);
5109 set_bit(STRIPE_DISCARD
, &sh
->state
);
5110 finish_wait(&conf
->wait_for_overlap
, &w
);
5111 sh
->overwrite_disks
= 0;
5112 for (d
= 0; d
< conf
->raid_disks
; d
++) {
5113 if (d
== sh
->pd_idx
|| d
== sh
->qd_idx
)
5115 sh
->dev
[d
].towrite
= bi
;
5116 set_bit(R5_OVERWRITE
, &sh
->dev
[d
].flags
);
5117 raid5_inc_bi_active_stripes(bi
);
5118 sh
->overwrite_disks
++;
5120 spin_unlock_irq(&sh
->stripe_lock
);
5121 if (conf
->mddev
->bitmap
) {
5123 d
< conf
->raid_disks
- conf
->max_degraded
;
5125 bitmap_startwrite(mddev
->bitmap
,
5129 sh
->bm_seq
= conf
->seq_flush
+ 1;
5130 set_bit(STRIPE_BIT_DELAY
, &sh
->state
);
5133 set_bit(STRIPE_HANDLE
, &sh
->state
);
5134 clear_bit(STRIPE_DELAYED
, &sh
->state
);
5135 if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
5136 atomic_inc(&conf
->preread_active_stripes
);
5137 release_stripe_plug(mddev
, sh
);
5140 remaining
= raid5_dec_bi_active_stripes(bi
);
5141 if (remaining
== 0) {
5142 md_write_end(mddev
);
5147 static void make_request(struct mddev
*mddev
, struct bio
* bi
)
5149 struct r5conf
*conf
= mddev
->private;
5151 sector_t new_sector
;
5152 sector_t logical_sector
, last_sector
;
5153 struct stripe_head
*sh
;
5154 const int rw
= bio_data_dir(bi
);
5159 if (unlikely(bi
->bi_rw
& REQ_FLUSH
)) {
5160 md_flush_request(mddev
, bi
);
5164 md_write_start(mddev
, bi
);
5167 * If array is degraded, better not do chunk aligned read because
5168 * later we might have to read it again in order to reconstruct
5169 * data on failed drives.
5171 if (rw
== READ
&& mddev
->degraded
== 0 &&
5172 mddev
->reshape_position
== MaxSector
&&
5173 chunk_aligned_read(mddev
,bi
))
5176 if (unlikely(bi
->bi_rw
& REQ_DISCARD
)) {
5177 make_discard_request(mddev
, bi
);
5181 logical_sector
= bi
->bi_iter
.bi_sector
& ~((sector_t
)STRIPE_SECTORS
-1);
5182 last_sector
= bio_end_sector(bi
);
5184 bi
->bi_phys_segments
= 1; /* over-loaded to count active stripes */
5186 prepare_to_wait(&conf
->wait_for_overlap
, &w
, TASK_UNINTERRUPTIBLE
);
5187 for (;logical_sector
< last_sector
; logical_sector
+= STRIPE_SECTORS
) {
5193 seq
= read_seqcount_begin(&conf
->gen_lock
);
5196 prepare_to_wait(&conf
->wait_for_overlap
, &w
,
5197 TASK_UNINTERRUPTIBLE
);
5198 if (unlikely(conf
->reshape_progress
!= MaxSector
)) {
5199 /* spinlock is needed as reshape_progress may be
5200 * 64bit on a 32bit platform, and so it might be
5201 * possible to see a half-updated value
5202 * Of course reshape_progress could change after
5203 * the lock is dropped, so once we get a reference
5204 * to the stripe that we think it is, we will have
5207 spin_lock_irq(&conf
->device_lock
);
5208 if (mddev
->reshape_backwards
5209 ? logical_sector
< conf
->reshape_progress
5210 : logical_sector
>= conf
->reshape_progress
) {
5213 if (mddev
->reshape_backwards
5214 ? logical_sector
< conf
->reshape_safe
5215 : logical_sector
>= conf
->reshape_safe
) {
5216 spin_unlock_irq(&conf
->device_lock
);
5222 spin_unlock_irq(&conf
->device_lock
);
5225 new_sector
= raid5_compute_sector(conf
, logical_sector
,
5228 pr_debug("raid456: make_request, sector %llu logical %llu\n",
5229 (unsigned long long)new_sector
,
5230 (unsigned long long)logical_sector
);
5232 sh
= get_active_stripe(conf
, new_sector
, previous
,
5233 (bi
->bi_rw
&RWA_MASK
), 0);
5235 if (unlikely(previous
)) {
5236 /* expansion might have moved on while waiting for a
5237 * stripe, so we must do the range check again.
5238 * Expansion could still move past after this
5239 * test, but as we are holding a reference to
5240 * 'sh', we know that if that happens,
5241 * STRIPE_EXPANDING will get set and the expansion
5242 * won't proceed until we finish with the stripe.
5245 spin_lock_irq(&conf
->device_lock
);
5246 if (mddev
->reshape_backwards
5247 ? logical_sector
>= conf
->reshape_progress
5248 : logical_sector
< conf
->reshape_progress
)
5249 /* mismatch, need to try again */
5251 spin_unlock_irq(&conf
->device_lock
);
5259 if (read_seqcount_retry(&conf
->gen_lock
, seq
)) {
5260 /* Might have got the wrong stripe_head
5268 logical_sector
>= mddev
->suspend_lo
&&
5269 logical_sector
< mddev
->suspend_hi
) {
5271 /* As the suspend_* range is controlled by
5272 * userspace, we want an interruptible
5275 flush_signals(current
);
5276 prepare_to_wait(&conf
->wait_for_overlap
,
5277 &w
, TASK_INTERRUPTIBLE
);
5278 if (logical_sector
>= mddev
->suspend_lo
&&
5279 logical_sector
< mddev
->suspend_hi
) {
5286 if (test_bit(STRIPE_EXPANDING
, &sh
->state
) ||
5287 !add_stripe_bio(sh
, bi
, dd_idx
, rw
, previous
)) {
5288 /* Stripe is busy expanding or
5289 * add failed due to overlap. Flush everything
5292 md_wakeup_thread(mddev
->thread
);
5298 set_bit(STRIPE_HANDLE
, &sh
->state
);
5299 clear_bit(STRIPE_DELAYED
, &sh
->state
);
5300 if ((!sh
->batch_head
|| sh
== sh
->batch_head
) &&
5301 (bi
->bi_rw
& REQ_SYNC
) &&
5302 !test_and_set_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
5303 atomic_inc(&conf
->preread_active_stripes
);
5304 release_stripe_plug(mddev
, sh
);
5306 /* cannot get stripe for read-ahead, just give-up */
5307 clear_bit(BIO_UPTODATE
, &bi
->bi_flags
);
5311 finish_wait(&conf
->wait_for_overlap
, &w
);
5313 remaining
= raid5_dec_bi_active_stripes(bi
);
5314 if (remaining
== 0) {
5317 md_write_end(mddev
);
5319 trace_block_bio_complete(bdev_get_queue(bi
->bi_bdev
),
5325 static sector_t
raid5_size(struct mddev
*mddev
, sector_t sectors
, int raid_disks
);
5327 static sector_t
reshape_request(struct mddev
*mddev
, sector_t sector_nr
, int *skipped
)
5329 /* reshaping is quite different to recovery/resync so it is
5330 * handled quite separately ... here.
5332 * On each call to sync_request, we gather one chunk worth of
5333 * destination stripes and flag them as expanding.
5334 * Then we find all the source stripes and request reads.
5335 * As the reads complete, handle_stripe will copy the data
5336 * into the destination stripe and release that stripe.
5338 struct r5conf
*conf
= mddev
->private;
5339 struct stripe_head
*sh
;
5340 sector_t first_sector
, last_sector
;
5341 int raid_disks
= conf
->previous_raid_disks
;
5342 int data_disks
= raid_disks
- conf
->max_degraded
;
5343 int new_data_disks
= conf
->raid_disks
- conf
->max_degraded
;
5346 sector_t writepos
, readpos
, safepos
;
5347 sector_t stripe_addr
;
5348 int reshape_sectors
;
5349 struct list_head stripes
;
5351 if (sector_nr
== 0) {
5352 /* If restarting in the middle, skip the initial sectors */
5353 if (mddev
->reshape_backwards
&&
5354 conf
->reshape_progress
< raid5_size(mddev
, 0, 0)) {
5355 sector_nr
= raid5_size(mddev
, 0, 0)
5356 - conf
->reshape_progress
;
5357 } else if (!mddev
->reshape_backwards
&&
5358 conf
->reshape_progress
> 0)
5359 sector_nr
= conf
->reshape_progress
;
5360 sector_div(sector_nr
, new_data_disks
);
5362 mddev
->curr_resync_completed
= sector_nr
;
5363 sysfs_notify(&mddev
->kobj
, NULL
, "sync_completed");
5369 /* We need to process a full chunk at a time.
5370 * If old and new chunk sizes differ, we need to process the
5373 if (mddev
->new_chunk_sectors
> mddev
->chunk_sectors
)
5374 reshape_sectors
= mddev
->new_chunk_sectors
;
5376 reshape_sectors
= mddev
->chunk_sectors
;
5378 /* We update the metadata at least every 10 seconds, or when
5379 * the data about to be copied would over-write the source of
5380 * the data at the front of the range. i.e. one new_stripe
5381 * along from reshape_progress new_maps to after where
5382 * reshape_safe old_maps to
5384 writepos
= conf
->reshape_progress
;
5385 sector_div(writepos
, new_data_disks
);
5386 readpos
= conf
->reshape_progress
;
5387 sector_div(readpos
, data_disks
);
5388 safepos
= conf
->reshape_safe
;
5389 sector_div(safepos
, data_disks
);
5390 if (mddev
->reshape_backwards
) {
5391 writepos
-= min_t(sector_t
, reshape_sectors
, writepos
);
5392 readpos
+= reshape_sectors
;
5393 safepos
+= reshape_sectors
;
5395 writepos
+= reshape_sectors
;
5396 readpos
-= min_t(sector_t
, reshape_sectors
, readpos
);
5397 safepos
-= min_t(sector_t
, reshape_sectors
, safepos
);
5400 /* Having calculated the 'writepos' possibly use it
5401 * to set 'stripe_addr' which is where we will write to.
5403 if (mddev
->reshape_backwards
) {
5404 BUG_ON(conf
->reshape_progress
== 0);
5405 stripe_addr
= writepos
;
5406 BUG_ON((mddev
->dev_sectors
&
5407 ~((sector_t
)reshape_sectors
- 1))
5408 - reshape_sectors
- stripe_addr
5411 BUG_ON(writepos
!= sector_nr
+ reshape_sectors
);
5412 stripe_addr
= sector_nr
;
5415 /* 'writepos' is the most advanced device address we might write.
5416 * 'readpos' is the least advanced device address we might read.
5417 * 'safepos' is the least address recorded in the metadata as having
5419 * If there is a min_offset_diff, these are adjusted either by
5420 * increasing the safepos/readpos if diff is negative, or
5421 * increasing writepos if diff is positive.
5422 * If 'readpos' is then behind 'writepos', there is no way that we can
5423 * ensure safety in the face of a crash - that must be done by userspace
5424 * making a backup of the data. So in that case there is no particular
5425 * rush to update metadata.
5426 * Otherwise if 'safepos' is behind 'writepos', then we really need to
5427 * update the metadata to advance 'safepos' to match 'readpos' so that
5428 * we can be safe in the event of a crash.
5429 * So we insist on updating metadata if safepos is behind writepos and
5430 * readpos is beyond writepos.
5431 * In any case, update the metadata every 10 seconds.
5432 * Maybe that number should be configurable, but I'm not sure it is
5433 * worth it.... maybe it could be a multiple of safemode_delay???
5435 if (conf
->min_offset_diff
< 0) {
5436 safepos
+= -conf
->min_offset_diff
;
5437 readpos
+= -conf
->min_offset_diff
;
5439 writepos
+= conf
->min_offset_diff
;
5441 if ((mddev
->reshape_backwards
5442 ? (safepos
> writepos
&& readpos
< writepos
)
5443 : (safepos
< writepos
&& readpos
> writepos
)) ||
5444 time_after(jiffies
, conf
->reshape_checkpoint
+ 10*HZ
)) {
5445 /* Cannot proceed until we've updated the superblock... */
5446 wait_event(conf
->wait_for_overlap
,
5447 atomic_read(&conf
->reshape_stripes
)==0
5448 || test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
));
5449 if (atomic_read(&conf
->reshape_stripes
) != 0)
5451 mddev
->reshape_position
= conf
->reshape_progress
;
5452 mddev
->curr_resync_completed
= sector_nr
;
5453 conf
->reshape_checkpoint
= jiffies
;
5454 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
5455 md_wakeup_thread(mddev
->thread
);
5456 wait_event(mddev
->sb_wait
, mddev
->flags
== 0 ||
5457 test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
));
5458 if (test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
))
5460 spin_lock_irq(&conf
->device_lock
);
5461 conf
->reshape_safe
= mddev
->reshape_position
;
5462 spin_unlock_irq(&conf
->device_lock
);
5463 wake_up(&conf
->wait_for_overlap
);
5464 sysfs_notify(&mddev
->kobj
, NULL
, "sync_completed");
5467 INIT_LIST_HEAD(&stripes
);
5468 for (i
= 0; i
< reshape_sectors
; i
+= STRIPE_SECTORS
) {
5470 int skipped_disk
= 0;
5471 sh
= get_active_stripe(conf
, stripe_addr
+i
, 0, 0, 1);
5472 set_bit(STRIPE_EXPANDING
, &sh
->state
);
5473 atomic_inc(&conf
->reshape_stripes
);
5474 /* If any of this stripe is beyond the end of the old
5475 * array, then we need to zero those blocks
5477 for (j
=sh
->disks
; j
--;) {
5479 if (j
== sh
->pd_idx
)
5481 if (conf
->level
== 6 &&
5484 s
= compute_blocknr(sh
, j
, 0);
5485 if (s
< raid5_size(mddev
, 0, 0)) {
5489 memset(page_address(sh
->dev
[j
].page
), 0, STRIPE_SIZE
);
5490 set_bit(R5_Expanded
, &sh
->dev
[j
].flags
);
5491 set_bit(R5_UPTODATE
, &sh
->dev
[j
].flags
);
5493 if (!skipped_disk
) {
5494 set_bit(STRIPE_EXPAND_READY
, &sh
->state
);
5495 set_bit(STRIPE_HANDLE
, &sh
->state
);
5497 list_add(&sh
->lru
, &stripes
);
5499 spin_lock_irq(&conf
->device_lock
);
5500 if (mddev
->reshape_backwards
)
5501 conf
->reshape_progress
-= reshape_sectors
* new_data_disks
;
5503 conf
->reshape_progress
+= reshape_sectors
* new_data_disks
;
5504 spin_unlock_irq(&conf
->device_lock
);
5505 /* Ok, those stripe are ready. We can start scheduling
5506 * reads on the source stripes.
5507 * The source stripes are determined by mapping the first and last
5508 * block on the destination stripes.
5511 raid5_compute_sector(conf
, stripe_addr
*(new_data_disks
),
5514 raid5_compute_sector(conf
, ((stripe_addr
+reshape_sectors
)
5515 * new_data_disks
- 1),
5517 if (last_sector
>= mddev
->dev_sectors
)
5518 last_sector
= mddev
->dev_sectors
- 1;
5519 while (first_sector
<= last_sector
) {
5520 sh
= get_active_stripe(conf
, first_sector
, 1, 0, 1);
5521 set_bit(STRIPE_EXPAND_SOURCE
, &sh
->state
);
5522 set_bit(STRIPE_HANDLE
, &sh
->state
);
5524 first_sector
+= STRIPE_SECTORS
;
5526 /* Now that the sources are clearly marked, we can release
5527 * the destination stripes
5529 while (!list_empty(&stripes
)) {
5530 sh
= list_entry(stripes
.next
, struct stripe_head
, lru
);
5531 list_del_init(&sh
->lru
);
5534 /* If this takes us to the resync_max point where we have to pause,
5535 * then we need to write out the superblock.
5537 sector_nr
+= reshape_sectors
;
5538 if ((sector_nr
- mddev
->curr_resync_completed
) * 2
5539 >= mddev
->resync_max
- mddev
->curr_resync_completed
) {
5540 /* Cannot proceed until we've updated the superblock... */
5541 wait_event(conf
->wait_for_overlap
,
5542 atomic_read(&conf
->reshape_stripes
) == 0
5543 || test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
));
5544 if (atomic_read(&conf
->reshape_stripes
) != 0)
5546 mddev
->reshape_position
= conf
->reshape_progress
;
5547 mddev
->curr_resync_completed
= sector_nr
;
5548 conf
->reshape_checkpoint
= jiffies
;
5549 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
5550 md_wakeup_thread(mddev
->thread
);
5551 wait_event(mddev
->sb_wait
,
5552 !test_bit(MD_CHANGE_DEVS
, &mddev
->flags
)
5553 || test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
));
5554 if (test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
))
5556 spin_lock_irq(&conf
->device_lock
);
5557 conf
->reshape_safe
= mddev
->reshape_position
;
5558 spin_unlock_irq(&conf
->device_lock
);
5559 wake_up(&conf
->wait_for_overlap
);
5560 sysfs_notify(&mddev
->kobj
, NULL
, "sync_completed");
5563 return reshape_sectors
;
5566 static inline sector_t
sync_request(struct mddev
*mddev
, sector_t sector_nr
, int *skipped
)
5568 struct r5conf
*conf
= mddev
->private;
5569 struct stripe_head
*sh
;
5570 sector_t max_sector
= mddev
->dev_sectors
;
5571 sector_t sync_blocks
;
5572 int still_degraded
= 0;
5575 if (sector_nr
>= max_sector
) {
5576 /* just being told to finish up .. nothing much to do */
5578 if (test_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
)) {
5583 if (mddev
->curr_resync
< max_sector
) /* aborted */
5584 bitmap_end_sync(mddev
->bitmap
, mddev
->curr_resync
,
5586 else /* completed sync */
5588 bitmap_close_sync(mddev
->bitmap
);
5593 /* Allow raid5_quiesce to complete */
5594 wait_event(conf
->wait_for_overlap
, conf
->quiesce
!= 2);
5596 if (test_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
))
5597 return reshape_request(mddev
, sector_nr
, skipped
);
5599 /* No need to check resync_max as we never do more than one
5600 * stripe, and as resync_max will always be on a chunk boundary,
5601 * if the check in md_do_sync didn't fire, there is no chance
5602 * of overstepping resync_max here
5605 /* if there is too many failed drives and we are trying
5606 * to resync, then assert that we are finished, because there is
5607 * nothing we can do.
5609 if (mddev
->degraded
>= conf
->max_degraded
&&
5610 test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
)) {
5611 sector_t rv
= mddev
->dev_sectors
- sector_nr
;
5615 if (!test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
) &&
5617 !bitmap_start_sync(mddev
->bitmap
, sector_nr
, &sync_blocks
, 1) &&
5618 sync_blocks
>= STRIPE_SECTORS
) {
5619 /* we can skip this block, and probably more */
5620 sync_blocks
/= STRIPE_SECTORS
;
5622 return sync_blocks
* STRIPE_SECTORS
; /* keep things rounded to whole stripes */
5625 bitmap_cond_end_sync(mddev
->bitmap
, sector_nr
);
5627 sh
= get_active_stripe(conf
, sector_nr
, 0, 1, 0);
5629 sh
= get_active_stripe(conf
, sector_nr
, 0, 0, 0);
5630 /* make sure we don't swamp the stripe cache if someone else
5631 * is trying to get access
5633 schedule_timeout_uninterruptible(1);
5635 /* Need to check if array will still be degraded after recovery/resync
5636 * Note in case of > 1 drive failures it's possible we're rebuilding
5637 * one drive while leaving another faulty drive in array.
5640 for (i
= 0; i
< conf
->raid_disks
; i
++) {
5641 struct md_rdev
*rdev
= ACCESS_ONCE(conf
->disks
[i
].rdev
);
5643 if (rdev
== NULL
|| test_bit(Faulty
, &rdev
->flags
))
5648 bitmap_start_sync(mddev
->bitmap
, sector_nr
, &sync_blocks
, still_degraded
);
5650 set_bit(STRIPE_SYNC_REQUESTED
, &sh
->state
);
5651 set_bit(STRIPE_HANDLE
, &sh
->state
);
5655 return STRIPE_SECTORS
;
5658 static int retry_aligned_read(struct r5conf
*conf
, struct bio
*raid_bio
)
5660 /* We may not be able to submit a whole bio at once as there
5661 * may not be enough stripe_heads available.
5662 * We cannot pre-allocate enough stripe_heads as we may need
5663 * more than exist in the cache (if we allow ever large chunks).
5664 * So we do one stripe head at a time and record in
5665 * ->bi_hw_segments how many have been done.
5667 * We *know* that this entire raid_bio is in one chunk, so
5668 * it will be only one 'dd_idx' and only need one call to raid5_compute_sector.
5670 struct stripe_head
*sh
;
5672 sector_t sector
, logical_sector
, last_sector
;
5677 logical_sector
= raid_bio
->bi_iter
.bi_sector
&
5678 ~((sector_t
)STRIPE_SECTORS
-1);
5679 sector
= raid5_compute_sector(conf
, logical_sector
,
5681 last_sector
= bio_end_sector(raid_bio
);
5683 for (; logical_sector
< last_sector
;
5684 logical_sector
+= STRIPE_SECTORS
,
5685 sector
+= STRIPE_SECTORS
,
5688 if (scnt
< raid5_bi_processed_stripes(raid_bio
))
5689 /* already done this stripe */
5692 sh
= get_active_stripe(conf
, sector
, 0, 1, 1);
5695 /* failed to get a stripe - must wait */
5696 raid5_set_bi_processed_stripes(raid_bio
, scnt
);
5697 conf
->retry_read_aligned
= raid_bio
;
5701 if (!add_stripe_bio(sh
, raid_bio
, dd_idx
, 0, 0)) {
5703 raid5_set_bi_processed_stripes(raid_bio
, scnt
);
5704 conf
->retry_read_aligned
= raid_bio
;
5708 set_bit(R5_ReadNoMerge
, &sh
->dev
[dd_idx
].flags
);
5713 remaining
= raid5_dec_bi_active_stripes(raid_bio
);
5714 if (remaining
== 0) {
5715 trace_block_bio_complete(bdev_get_queue(raid_bio
->bi_bdev
),
5717 bio_endio(raid_bio
, 0);
5719 if (atomic_dec_and_test(&conf
->active_aligned_reads
))
5720 wake_up(&conf
->wait_for_quiescent
);
5724 static int handle_active_stripes(struct r5conf
*conf
, int group
,
5725 struct r5worker
*worker
,
5726 struct list_head
*temp_inactive_list
)
5728 struct stripe_head
*batch
[MAX_STRIPE_BATCH
], *sh
;
5729 int i
, batch_size
= 0, hash
;
5730 bool release_inactive
= false;
5732 while (batch_size
< MAX_STRIPE_BATCH
&&
5733 (sh
= __get_priority_stripe(conf
, group
)) != NULL
)
5734 batch
[batch_size
++] = sh
;
5736 if (batch_size
== 0) {
5737 for (i
= 0; i
< NR_STRIPE_HASH_LOCKS
; i
++)
5738 if (!list_empty(temp_inactive_list
+ i
))
5740 if (i
== NR_STRIPE_HASH_LOCKS
)
5742 release_inactive
= true;
5744 spin_unlock_irq(&conf
->device_lock
);
5746 release_inactive_stripe_list(conf
, temp_inactive_list
,
5747 NR_STRIPE_HASH_LOCKS
);
5749 if (release_inactive
) {
5750 spin_lock_irq(&conf
->device_lock
);
5754 for (i
= 0; i
< batch_size
; i
++)
5755 handle_stripe(batch
[i
]);
5759 spin_lock_irq(&conf
->device_lock
);
5760 for (i
= 0; i
< batch_size
; i
++) {
5761 hash
= batch
[i
]->hash_lock_index
;
5762 __release_stripe(conf
, batch
[i
], &temp_inactive_list
[hash
]);
5767 static void raid5_do_work(struct work_struct
*work
)
5769 struct r5worker
*worker
= container_of(work
, struct r5worker
, work
);
5770 struct r5worker_group
*group
= worker
->group
;
5771 struct r5conf
*conf
= group
->conf
;
5772 int group_id
= group
- conf
->worker_groups
;
5774 struct blk_plug plug
;
5776 pr_debug("+++ raid5worker active\n");
5778 blk_start_plug(&plug
);
5780 spin_lock_irq(&conf
->device_lock
);
5782 int batch_size
, released
;
5784 released
= release_stripe_list(conf
, worker
->temp_inactive_list
);
5786 batch_size
= handle_active_stripes(conf
, group_id
, worker
,
5787 worker
->temp_inactive_list
);
5788 worker
->working
= false;
5789 if (!batch_size
&& !released
)
5791 handled
+= batch_size
;
5793 pr_debug("%d stripes handled\n", handled
);
5795 spin_unlock_irq(&conf
->device_lock
);
5796 blk_finish_plug(&plug
);
5798 pr_debug("--- raid5worker inactive\n");
5802 * This is our raid5 kernel thread.
5804 * We scan the hash table for stripes which can be handled now.
5805 * During the scan, completed stripes are saved for us by the interrupt
5806 * handler, so that they will not have to wait for our next wakeup.
5808 static void raid5d(struct md_thread
*thread
)
5810 struct mddev
*mddev
= thread
->mddev
;
5811 struct r5conf
*conf
= mddev
->private;
5813 struct blk_plug plug
;
5815 pr_debug("+++ raid5d active\n");
5817 md_check_recovery(mddev
);
5819 blk_start_plug(&plug
);
5821 spin_lock_irq(&conf
->device_lock
);
5824 int batch_size
, released
;
5826 released
= release_stripe_list(conf
, conf
->temp_inactive_list
);
5828 clear_bit(R5_DID_ALLOC
, &conf
->cache_state
);
5831 !list_empty(&conf
->bitmap_list
)) {
5832 /* Now is a good time to flush some bitmap updates */
5834 spin_unlock_irq(&conf
->device_lock
);
5835 bitmap_unplug(mddev
->bitmap
);
5836 spin_lock_irq(&conf
->device_lock
);
5837 conf
->seq_write
= conf
->seq_flush
;
5838 activate_bit_delay(conf
, conf
->temp_inactive_list
);
5840 raid5_activate_delayed(conf
);
5842 while ((bio
= remove_bio_from_retry(conf
))) {
5844 spin_unlock_irq(&conf
->device_lock
);
5845 ok
= retry_aligned_read(conf
, bio
);
5846 spin_lock_irq(&conf
->device_lock
);
5852 batch_size
= handle_active_stripes(conf
, ANY_GROUP
, NULL
,
5853 conf
->temp_inactive_list
);
5854 if (!batch_size
&& !released
)
5856 handled
+= batch_size
;
5858 if (mddev
->flags
& ~(1<<MD_CHANGE_PENDING
)) {
5859 spin_unlock_irq(&conf
->device_lock
);
5860 md_check_recovery(mddev
);
5861 spin_lock_irq(&conf
->device_lock
);
5864 pr_debug("%d stripes handled\n", handled
);
5866 spin_unlock_irq(&conf
->device_lock
);
5867 if (test_and_clear_bit(R5_ALLOC_MORE
, &conf
->cache_state
) &&
5868 mutex_trylock(&conf
->cache_size_mutex
)) {
5869 grow_one_stripe(conf
, __GFP_NOWARN
);
5870 /* Set flag even if allocation failed. This helps
5871 * slow down allocation requests when mem is short
5873 set_bit(R5_DID_ALLOC
, &conf
->cache_state
);
5874 mutex_unlock(&conf
->cache_size_mutex
);
5877 async_tx_issue_pending_all();
5878 blk_finish_plug(&plug
);
5880 pr_debug("--- raid5d inactive\n");
5884 raid5_show_stripe_cache_size(struct mddev
*mddev
, char *page
)
5886 struct r5conf
*conf
;
5888 spin_lock(&mddev
->lock
);
5889 conf
= mddev
->private;
5891 ret
= sprintf(page
, "%d\n", conf
->min_nr_stripes
);
5892 spin_unlock(&mddev
->lock
);
5897 raid5_set_cache_size(struct mddev
*mddev
, int size
)
5899 struct r5conf
*conf
= mddev
->private;
5902 if (size
<= 16 || size
> 32768)
5905 conf
->min_nr_stripes
= size
;
5906 mutex_lock(&conf
->cache_size_mutex
);
5907 while (size
< conf
->max_nr_stripes
&&
5908 drop_one_stripe(conf
))
5910 mutex_unlock(&conf
->cache_size_mutex
);
5913 err
= md_allow_write(mddev
);
5917 mutex_lock(&conf
->cache_size_mutex
);
5918 while (size
> conf
->max_nr_stripes
)
5919 if (!grow_one_stripe(conf
, GFP_KERNEL
))
5921 mutex_unlock(&conf
->cache_size_mutex
);
5925 EXPORT_SYMBOL(raid5_set_cache_size
);
5928 raid5_store_stripe_cache_size(struct mddev
*mddev
, const char *page
, size_t len
)
5930 struct r5conf
*conf
;
5934 if (len
>= PAGE_SIZE
)
5936 if (kstrtoul(page
, 10, &new))
5938 err
= mddev_lock(mddev
);
5941 conf
= mddev
->private;
5945 err
= raid5_set_cache_size(mddev
, new);
5946 mddev_unlock(mddev
);
5951 static struct md_sysfs_entry
5952 raid5_stripecache_size
= __ATTR(stripe_cache_size
, S_IRUGO
| S_IWUSR
,
5953 raid5_show_stripe_cache_size
,
5954 raid5_store_stripe_cache_size
);
5957 raid5_show_rmw_level(struct mddev
*mddev
, char *page
)
5959 struct r5conf
*conf
= mddev
->private;
5961 return sprintf(page
, "%d\n", conf
->rmw_level
);
5967 raid5_store_rmw_level(struct mddev
*mddev
, const char *page
, size_t len
)
5969 struct r5conf
*conf
= mddev
->private;
5975 if (len
>= PAGE_SIZE
)
5978 if (kstrtoul(page
, 10, &new))
5981 if (new != PARITY_DISABLE_RMW
&& !raid6_call
.xor_syndrome
)
5984 if (new != PARITY_DISABLE_RMW
&&
5985 new != PARITY_ENABLE_RMW
&&
5986 new != PARITY_PREFER_RMW
)
5989 conf
->rmw_level
= new;
5993 static struct md_sysfs_entry
5994 raid5_rmw_level
= __ATTR(rmw_level
, S_IRUGO
| S_IWUSR
,
5995 raid5_show_rmw_level
,
5996 raid5_store_rmw_level
);
6000 raid5_show_preread_threshold(struct mddev
*mddev
, char *page
)
6002 struct r5conf
*conf
;
6004 spin_lock(&mddev
->lock
);
6005 conf
= mddev
->private;
6007 ret
= sprintf(page
, "%d\n", conf
->bypass_threshold
);
6008 spin_unlock(&mddev
->lock
);
6013 raid5_store_preread_threshold(struct mddev
*mddev
, const char *page
, size_t len
)
6015 struct r5conf
*conf
;
6019 if (len
>= PAGE_SIZE
)
6021 if (kstrtoul(page
, 10, &new))
6024 err
= mddev_lock(mddev
);
6027 conf
= mddev
->private;
6030 else if (new > conf
->min_nr_stripes
)
6033 conf
->bypass_threshold
= new;
6034 mddev_unlock(mddev
);
6038 static struct md_sysfs_entry
6039 raid5_preread_bypass_threshold
= __ATTR(preread_bypass_threshold
,
6041 raid5_show_preread_threshold
,
6042 raid5_store_preread_threshold
);
6045 raid5_show_skip_copy(struct mddev
*mddev
, char *page
)
6047 struct r5conf
*conf
;
6049 spin_lock(&mddev
->lock
);
6050 conf
= mddev
->private;
6052 ret
= sprintf(page
, "%d\n", conf
->skip_copy
);
6053 spin_unlock(&mddev
->lock
);
6058 raid5_store_skip_copy(struct mddev
*mddev
, const char *page
, size_t len
)
6060 struct r5conf
*conf
;
6064 if (len
>= PAGE_SIZE
)
6066 if (kstrtoul(page
, 10, &new))
6070 err
= mddev_lock(mddev
);
6073 conf
= mddev
->private;
6076 else if (new != conf
->skip_copy
) {
6077 mddev_suspend(mddev
);
6078 conf
->skip_copy
= new;
6080 mddev
->queue
->backing_dev_info
.capabilities
|=
6081 BDI_CAP_STABLE_WRITES
;
6083 mddev
->queue
->backing_dev_info
.capabilities
&=
6084 ~BDI_CAP_STABLE_WRITES
;
6085 mddev_resume(mddev
);
6087 mddev_unlock(mddev
);
6091 static struct md_sysfs_entry
6092 raid5_skip_copy
= __ATTR(skip_copy
, S_IRUGO
| S_IWUSR
,
6093 raid5_show_skip_copy
,
6094 raid5_store_skip_copy
);
6097 stripe_cache_active_show(struct mddev
*mddev
, char *page
)
6099 struct r5conf
*conf
= mddev
->private;
6101 return sprintf(page
, "%d\n", atomic_read(&conf
->active_stripes
));
6106 static struct md_sysfs_entry
6107 raid5_stripecache_active
= __ATTR_RO(stripe_cache_active
);
6110 raid5_show_group_thread_cnt(struct mddev
*mddev
, char *page
)
6112 struct r5conf
*conf
;
6114 spin_lock(&mddev
->lock
);
6115 conf
= mddev
->private;
6117 ret
= sprintf(page
, "%d\n", conf
->worker_cnt_per_group
);
6118 spin_unlock(&mddev
->lock
);
6122 static int alloc_thread_groups(struct r5conf
*conf
, int cnt
,
6124 int *worker_cnt_per_group
,
6125 struct r5worker_group
**worker_groups
);
6127 raid5_store_group_thread_cnt(struct mddev
*mddev
, const char *page
, size_t len
)
6129 struct r5conf
*conf
;
6132 struct r5worker_group
*new_groups
, *old_groups
;
6133 int group_cnt
, worker_cnt_per_group
;
6135 if (len
>= PAGE_SIZE
)
6137 if (kstrtoul(page
, 10, &new))
6140 err
= mddev_lock(mddev
);
6143 conf
= mddev
->private;
6146 else if (new != conf
->worker_cnt_per_group
) {
6147 mddev_suspend(mddev
);
6149 old_groups
= conf
->worker_groups
;
6151 flush_workqueue(raid5_wq
);
6153 err
= alloc_thread_groups(conf
, new,
6154 &group_cnt
, &worker_cnt_per_group
,
6157 spin_lock_irq(&conf
->device_lock
);
6158 conf
->group_cnt
= group_cnt
;
6159 conf
->worker_cnt_per_group
= worker_cnt_per_group
;
6160 conf
->worker_groups
= new_groups
;
6161 spin_unlock_irq(&conf
->device_lock
);
6164 kfree(old_groups
[0].workers
);
6167 mddev_resume(mddev
);
6169 mddev_unlock(mddev
);
6174 static struct md_sysfs_entry
6175 raid5_group_thread_cnt
= __ATTR(group_thread_cnt
, S_IRUGO
| S_IWUSR
,
6176 raid5_show_group_thread_cnt
,
6177 raid5_store_group_thread_cnt
);
6179 static struct attribute
*raid5_attrs
[] = {
6180 &raid5_stripecache_size
.attr
,
6181 &raid5_stripecache_active
.attr
,
6182 &raid5_preread_bypass_threshold
.attr
,
6183 &raid5_group_thread_cnt
.attr
,
6184 &raid5_skip_copy
.attr
,
6185 &raid5_rmw_level
.attr
,
6188 static struct attribute_group raid5_attrs_group
= {
6190 .attrs
= raid5_attrs
,
6193 static int alloc_thread_groups(struct r5conf
*conf
, int cnt
,
6195 int *worker_cnt_per_group
,
6196 struct r5worker_group
**worker_groups
)
6200 struct r5worker
*workers
;
6202 *worker_cnt_per_group
= cnt
;
6205 *worker_groups
= NULL
;
6208 *group_cnt
= num_possible_nodes();
6209 size
= sizeof(struct r5worker
) * cnt
;
6210 workers
= kzalloc(size
* *group_cnt
, GFP_NOIO
);
6211 *worker_groups
= kzalloc(sizeof(struct r5worker_group
) *
6212 *group_cnt
, GFP_NOIO
);
6213 if (!*worker_groups
|| !workers
) {
6215 kfree(*worker_groups
);
6219 for (i
= 0; i
< *group_cnt
; i
++) {
6220 struct r5worker_group
*group
;
6222 group
= &(*worker_groups
)[i
];
6223 INIT_LIST_HEAD(&group
->handle_list
);
6225 group
->workers
= workers
+ i
* cnt
;
6227 for (j
= 0; j
< cnt
; j
++) {
6228 struct r5worker
*worker
= group
->workers
+ j
;
6229 worker
->group
= group
;
6230 INIT_WORK(&worker
->work
, raid5_do_work
);
6232 for (k
= 0; k
< NR_STRIPE_HASH_LOCKS
; k
++)
6233 INIT_LIST_HEAD(worker
->temp_inactive_list
+ k
);
6240 static void free_thread_groups(struct r5conf
*conf
)
6242 if (conf
->worker_groups
)
6243 kfree(conf
->worker_groups
[0].workers
);
6244 kfree(conf
->worker_groups
);
6245 conf
->worker_groups
= NULL
;
6249 raid5_size(struct mddev
*mddev
, sector_t sectors
, int raid_disks
)
6251 struct r5conf
*conf
= mddev
->private;
6254 sectors
= mddev
->dev_sectors
;
6256 /* size is defined by the smallest of previous and new size */
6257 raid_disks
= min(conf
->raid_disks
, conf
->previous_raid_disks
);
6259 sectors
&= ~((sector_t
)mddev
->chunk_sectors
- 1);
6260 sectors
&= ~((sector_t
)mddev
->new_chunk_sectors
- 1);
6261 return sectors
* (raid_disks
- conf
->max_degraded
);
6264 static void free_scratch_buffer(struct r5conf
*conf
, struct raid5_percpu
*percpu
)
6266 safe_put_page(percpu
->spare_page
);
6267 if (percpu
->scribble
)
6268 flex_array_free(percpu
->scribble
);
6269 percpu
->spare_page
= NULL
;
6270 percpu
->scribble
= NULL
;
6273 static int alloc_scratch_buffer(struct r5conf
*conf
, struct raid5_percpu
*percpu
)
6275 if (conf
->level
== 6 && !percpu
->spare_page
)
6276 percpu
->spare_page
= alloc_page(GFP_KERNEL
);
6277 if (!percpu
->scribble
)
6278 percpu
->scribble
= scribble_alloc(max(conf
->raid_disks
,
6279 conf
->previous_raid_disks
),
6280 max(conf
->chunk_sectors
,
6281 conf
->prev_chunk_sectors
)
6285 if (!percpu
->scribble
|| (conf
->level
== 6 && !percpu
->spare_page
)) {
6286 free_scratch_buffer(conf
, percpu
);
6293 static void raid5_free_percpu(struct r5conf
*conf
)
6300 #ifdef CONFIG_HOTPLUG_CPU
6301 unregister_cpu_notifier(&conf
->cpu_notify
);
6305 for_each_possible_cpu(cpu
)
6306 free_scratch_buffer(conf
, per_cpu_ptr(conf
->percpu
, cpu
));
6309 free_percpu(conf
->percpu
);
6312 static void free_conf(struct r5conf
*conf
)
6314 if (conf
->shrinker
.seeks
)
6315 unregister_shrinker(&conf
->shrinker
);
6316 free_thread_groups(conf
);
6317 shrink_stripes(conf
);
6318 raid5_free_percpu(conf
);
6320 kfree(conf
->stripe_hashtbl
);
6324 #ifdef CONFIG_HOTPLUG_CPU
6325 static int raid456_cpu_notify(struct notifier_block
*nfb
, unsigned long action
,
6328 struct r5conf
*conf
= container_of(nfb
, struct r5conf
, cpu_notify
);
6329 long cpu
= (long)hcpu
;
6330 struct raid5_percpu
*percpu
= per_cpu_ptr(conf
->percpu
, cpu
);
6333 case CPU_UP_PREPARE
:
6334 case CPU_UP_PREPARE_FROZEN
:
6335 if (alloc_scratch_buffer(conf
, percpu
)) {
6336 pr_err("%s: failed memory allocation for cpu%ld\n",
6338 return notifier_from_errno(-ENOMEM
);
6342 case CPU_DEAD_FROZEN
:
6343 free_scratch_buffer(conf
, per_cpu_ptr(conf
->percpu
, cpu
));
6352 static int raid5_alloc_percpu(struct r5conf
*conf
)
6357 conf
->percpu
= alloc_percpu(struct raid5_percpu
);
6361 #ifdef CONFIG_HOTPLUG_CPU
6362 conf
->cpu_notify
.notifier_call
= raid456_cpu_notify
;
6363 conf
->cpu_notify
.priority
= 0;
6364 err
= register_cpu_notifier(&conf
->cpu_notify
);
6370 for_each_present_cpu(cpu
) {
6371 err
= alloc_scratch_buffer(conf
, per_cpu_ptr(conf
->percpu
, cpu
));
6373 pr_err("%s: failed memory allocation for cpu%ld\n",
6383 static unsigned long raid5_cache_scan(struct shrinker
*shrink
,
6384 struct shrink_control
*sc
)
6386 struct r5conf
*conf
= container_of(shrink
, struct r5conf
, shrinker
);
6387 unsigned long ret
= SHRINK_STOP
;
6389 if (mutex_trylock(&conf
->cache_size_mutex
)) {
6391 while (ret
< sc
->nr_to_scan
&&
6392 conf
->max_nr_stripes
> conf
->min_nr_stripes
) {
6393 if (drop_one_stripe(conf
) == 0) {
6399 mutex_unlock(&conf
->cache_size_mutex
);
6404 static unsigned long raid5_cache_count(struct shrinker
*shrink
,
6405 struct shrink_control
*sc
)
6407 struct r5conf
*conf
= container_of(shrink
, struct r5conf
, shrinker
);
6409 if (conf
->max_nr_stripes
< conf
->min_nr_stripes
)
6410 /* unlikely, but not impossible */
6412 return conf
->max_nr_stripes
- conf
->min_nr_stripes
;
6415 static struct r5conf
*setup_conf(struct mddev
*mddev
)
6417 struct r5conf
*conf
;
6418 int raid_disk
, memory
, max_disks
;
6419 struct md_rdev
*rdev
;
6420 struct disk_info
*disk
;
6423 int group_cnt
, worker_cnt_per_group
;
6424 struct r5worker_group
*new_group
;
6426 if (mddev
->new_level
!= 5
6427 && mddev
->new_level
!= 4
6428 && mddev
->new_level
!= 6) {
6429 printk(KERN_ERR
"md/raid:%s: raid level not set to 4/5/6 (%d)\n",
6430 mdname(mddev
), mddev
->new_level
);
6431 return ERR_PTR(-EIO
);
6433 if ((mddev
->new_level
== 5
6434 && !algorithm_valid_raid5(mddev
->new_layout
)) ||
6435 (mddev
->new_level
== 6
6436 && !algorithm_valid_raid6(mddev
->new_layout
))) {
6437 printk(KERN_ERR
"md/raid:%s: layout %d not supported\n",
6438 mdname(mddev
), mddev
->new_layout
);
6439 return ERR_PTR(-EIO
);
6441 if (mddev
->new_level
== 6 && mddev
->raid_disks
< 4) {
6442 printk(KERN_ERR
"md/raid:%s: not enough configured devices (%d, minimum 4)\n",
6443 mdname(mddev
), mddev
->raid_disks
);
6444 return ERR_PTR(-EINVAL
);
6447 if (!mddev
->new_chunk_sectors
||
6448 (mddev
->new_chunk_sectors
<< 9) % PAGE_SIZE
||
6449 !is_power_of_2(mddev
->new_chunk_sectors
)) {
6450 printk(KERN_ERR
"md/raid:%s: invalid chunk size %d\n",
6451 mdname(mddev
), mddev
->new_chunk_sectors
<< 9);
6452 return ERR_PTR(-EINVAL
);
6455 conf
= kzalloc(sizeof(struct r5conf
), GFP_KERNEL
);
6458 /* Don't enable multi-threading by default*/
6459 if (!alloc_thread_groups(conf
, 0, &group_cnt
, &worker_cnt_per_group
,
6461 conf
->group_cnt
= group_cnt
;
6462 conf
->worker_cnt_per_group
= worker_cnt_per_group
;
6463 conf
->worker_groups
= new_group
;
6466 spin_lock_init(&conf
->device_lock
);
6467 seqcount_init(&conf
->gen_lock
);
6468 mutex_init(&conf
->cache_size_mutex
);
6469 init_waitqueue_head(&conf
->wait_for_quiescent
);
6470 for (i
= 0; i
< NR_STRIPE_HASH_LOCKS
; i
++) {
6471 init_waitqueue_head(&conf
->wait_for_stripe
[i
]);
6473 init_waitqueue_head(&conf
->wait_for_overlap
);
6474 INIT_LIST_HEAD(&conf
->handle_list
);
6475 INIT_LIST_HEAD(&conf
->hold_list
);
6476 INIT_LIST_HEAD(&conf
->delayed_list
);
6477 INIT_LIST_HEAD(&conf
->bitmap_list
);
6478 init_llist_head(&conf
->released_stripes
);
6479 atomic_set(&conf
->active_stripes
, 0);
6480 atomic_set(&conf
->preread_active_stripes
, 0);
6481 atomic_set(&conf
->active_aligned_reads
, 0);
6482 conf
->bypass_threshold
= BYPASS_THRESHOLD
;
6483 conf
->recovery_disabled
= mddev
->recovery_disabled
- 1;
6485 conf
->raid_disks
= mddev
->raid_disks
;
6486 if (mddev
->reshape_position
== MaxSector
)
6487 conf
->previous_raid_disks
= mddev
->raid_disks
;
6489 conf
->previous_raid_disks
= mddev
->raid_disks
- mddev
->delta_disks
;
6490 max_disks
= max(conf
->raid_disks
, conf
->previous_raid_disks
);
6492 conf
->disks
= kzalloc(max_disks
* sizeof(struct disk_info
),
6497 conf
->mddev
= mddev
;
6499 if ((conf
->stripe_hashtbl
= kzalloc(PAGE_SIZE
, GFP_KERNEL
)) == NULL
)
6502 /* We init hash_locks[0] separately to that it can be used
6503 * as the reference lock in the spin_lock_nest_lock() call
6504 * in lock_all_device_hash_locks_irq in order to convince
6505 * lockdep that we know what we are doing.
6507 spin_lock_init(conf
->hash_locks
);
6508 for (i
= 1; i
< NR_STRIPE_HASH_LOCKS
; i
++)
6509 spin_lock_init(conf
->hash_locks
+ i
);
6511 for (i
= 0; i
< NR_STRIPE_HASH_LOCKS
; i
++)
6512 INIT_LIST_HEAD(conf
->inactive_list
+ i
);
6514 for (i
= 0; i
< NR_STRIPE_HASH_LOCKS
; i
++)
6515 INIT_LIST_HEAD(conf
->temp_inactive_list
+ i
);
6517 conf
->level
= mddev
->new_level
;
6518 conf
->chunk_sectors
= mddev
->new_chunk_sectors
;
6519 if (raid5_alloc_percpu(conf
) != 0)
6522 pr_debug("raid456: run(%s) called.\n", mdname(mddev
));
6524 rdev_for_each(rdev
, mddev
) {
6525 raid_disk
= rdev
->raid_disk
;
6526 if (raid_disk
>= max_disks
6529 disk
= conf
->disks
+ raid_disk
;
6531 if (test_bit(Replacement
, &rdev
->flags
)) {
6532 if (disk
->replacement
)
6534 disk
->replacement
= rdev
;
6541 if (test_bit(In_sync
, &rdev
->flags
)) {
6542 char b
[BDEVNAME_SIZE
];
6543 printk(KERN_INFO
"md/raid:%s: device %s operational as raid"
6545 mdname(mddev
), bdevname(rdev
->bdev
, b
), raid_disk
);
6546 } else if (rdev
->saved_raid_disk
!= raid_disk
)
6547 /* Cannot rely on bitmap to complete recovery */
6551 conf
->level
= mddev
->new_level
;
6552 if (conf
->level
== 6) {
6553 conf
->max_degraded
= 2;
6554 if (raid6_call
.xor_syndrome
)
6555 conf
->rmw_level
= PARITY_ENABLE_RMW
;
6557 conf
->rmw_level
= PARITY_DISABLE_RMW
;
6559 conf
->max_degraded
= 1;
6560 conf
->rmw_level
= PARITY_ENABLE_RMW
;
6562 conf
->algorithm
= mddev
->new_layout
;
6563 conf
->reshape_progress
= mddev
->reshape_position
;
6564 if (conf
->reshape_progress
!= MaxSector
) {
6565 conf
->prev_chunk_sectors
= mddev
->chunk_sectors
;
6566 conf
->prev_algo
= mddev
->layout
;
6569 conf
->min_nr_stripes
= NR_STRIPES
;
6570 memory
= conf
->min_nr_stripes
* (sizeof(struct stripe_head
) +
6571 max_disks
* ((sizeof(struct bio
) + PAGE_SIZE
))) / 1024;
6572 atomic_set(&conf
->empty_inactive_list_nr
, NR_STRIPE_HASH_LOCKS
);
6573 if (grow_stripes(conf
, conf
->min_nr_stripes
)) {
6575 "md/raid:%s: couldn't allocate %dkB for buffers\n",
6576 mdname(mddev
), memory
);
6579 printk(KERN_INFO
"md/raid:%s: allocated %dkB\n",
6580 mdname(mddev
), memory
);
6582 * Losing a stripe head costs more than the time to refill it,
6583 * it reduces the queue depth and so can hurt throughput.
6584 * So set it rather large, scaled by number of devices.
6586 conf
->shrinker
.seeks
= DEFAULT_SEEKS
* conf
->raid_disks
* 4;
6587 conf
->shrinker
.scan_objects
= raid5_cache_scan
;
6588 conf
->shrinker
.count_objects
= raid5_cache_count
;
6589 conf
->shrinker
.batch
= 128;
6590 conf
->shrinker
.flags
= 0;
6591 register_shrinker(&conf
->shrinker
);
6593 sprintf(pers_name
, "raid%d", mddev
->new_level
);
6594 conf
->thread
= md_register_thread(raid5d
, mddev
, pers_name
);
6595 if (!conf
->thread
) {
6597 "md/raid:%s: couldn't allocate thread.\n",
6607 return ERR_PTR(-EIO
);
6609 return ERR_PTR(-ENOMEM
);
6612 static int only_parity(int raid_disk
, int algo
, int raid_disks
, int max_degraded
)
6615 case ALGORITHM_PARITY_0
:
6616 if (raid_disk
< max_degraded
)
6619 case ALGORITHM_PARITY_N
:
6620 if (raid_disk
>= raid_disks
- max_degraded
)
6623 case ALGORITHM_PARITY_0_6
:
6624 if (raid_disk
== 0 ||
6625 raid_disk
== raid_disks
- 1)
6628 case ALGORITHM_LEFT_ASYMMETRIC_6
:
6629 case ALGORITHM_RIGHT_ASYMMETRIC_6
:
6630 case ALGORITHM_LEFT_SYMMETRIC_6
:
6631 case ALGORITHM_RIGHT_SYMMETRIC_6
:
6632 if (raid_disk
== raid_disks
- 1)
6638 static int run(struct mddev
*mddev
)
6640 struct r5conf
*conf
;
6641 int working_disks
= 0;
6642 int dirty_parity_disks
= 0;
6643 struct md_rdev
*rdev
;
6644 sector_t reshape_offset
= 0;
6646 long long min_offset_diff
= 0;
6649 if (mddev
->recovery_cp
!= MaxSector
)
6650 printk(KERN_NOTICE
"md/raid:%s: not clean"
6651 " -- starting background reconstruction\n",
6654 rdev_for_each(rdev
, mddev
) {
6656 if (rdev
->raid_disk
< 0)
6658 diff
= (rdev
->new_data_offset
- rdev
->data_offset
);
6660 min_offset_diff
= diff
;
6662 } else if (mddev
->reshape_backwards
&&
6663 diff
< min_offset_diff
)
6664 min_offset_diff
= diff
;
6665 else if (!mddev
->reshape_backwards
&&
6666 diff
> min_offset_diff
)
6667 min_offset_diff
= diff
;
6670 if (mddev
->reshape_position
!= MaxSector
) {
6671 /* Check that we can continue the reshape.
6672 * Difficulties arise if the stripe we would write to
6673 * next is at or after the stripe we would read from next.
6674 * For a reshape that changes the number of devices, this
6675 * is only possible for a very short time, and mdadm makes
6676 * sure that time appears to have past before assembling
6677 * the array. So we fail if that time hasn't passed.
6678 * For a reshape that keeps the number of devices the same
6679 * mdadm must be monitoring the reshape can keeping the
6680 * critical areas read-only and backed up. It will start
6681 * the array in read-only mode, so we check for that.
6683 sector_t here_new
, here_old
;
6685 int max_degraded
= (mddev
->level
== 6 ? 2 : 1);
6687 if (mddev
->new_level
!= mddev
->level
) {
6688 printk(KERN_ERR
"md/raid:%s: unsupported reshape "
6689 "required - aborting.\n",
6693 old_disks
= mddev
->raid_disks
- mddev
->delta_disks
;
6694 /* reshape_position must be on a new-stripe boundary, and one
6695 * further up in new geometry must map after here in old
6698 here_new
= mddev
->reshape_position
;
6699 if (sector_div(here_new
, mddev
->new_chunk_sectors
*
6700 (mddev
->raid_disks
- max_degraded
))) {
6701 printk(KERN_ERR
"md/raid:%s: reshape_position not "
6702 "on a stripe boundary\n", mdname(mddev
));
6705 reshape_offset
= here_new
* mddev
->new_chunk_sectors
;
6706 /* here_new is the stripe we will write to */
6707 here_old
= mddev
->reshape_position
;
6708 sector_div(here_old
, mddev
->chunk_sectors
*
6709 (old_disks
-max_degraded
));
6710 /* here_old is the first stripe that we might need to read
6712 if (mddev
->delta_disks
== 0) {
6713 if ((here_new
* mddev
->new_chunk_sectors
!=
6714 here_old
* mddev
->chunk_sectors
)) {
6715 printk(KERN_ERR
"md/raid:%s: reshape position is"
6716 " confused - aborting\n", mdname(mddev
));
6719 /* We cannot be sure it is safe to start an in-place
6720 * reshape. It is only safe if user-space is monitoring
6721 * and taking constant backups.
6722 * mdadm always starts a situation like this in
6723 * readonly mode so it can take control before
6724 * allowing any writes. So just check for that.
6726 if (abs(min_offset_diff
) >= mddev
->chunk_sectors
&&
6727 abs(min_offset_diff
) >= mddev
->new_chunk_sectors
)
6728 /* not really in-place - so OK */;
6729 else if (mddev
->ro
== 0) {
6730 printk(KERN_ERR
"md/raid:%s: in-place reshape "
6731 "must be started in read-only mode "
6736 } else if (mddev
->reshape_backwards
6737 ? (here_new
* mddev
->new_chunk_sectors
+ min_offset_diff
<=
6738 here_old
* mddev
->chunk_sectors
)
6739 : (here_new
* mddev
->new_chunk_sectors
>=
6740 here_old
* mddev
->chunk_sectors
+ (-min_offset_diff
))) {
6741 /* Reading from the same stripe as writing to - bad */
6742 printk(KERN_ERR
"md/raid:%s: reshape_position too early for "
6743 "auto-recovery - aborting.\n",
6747 printk(KERN_INFO
"md/raid:%s: reshape will continue\n",
6749 /* OK, we should be able to continue; */
6751 BUG_ON(mddev
->level
!= mddev
->new_level
);
6752 BUG_ON(mddev
->layout
!= mddev
->new_layout
);
6753 BUG_ON(mddev
->chunk_sectors
!= mddev
->new_chunk_sectors
);
6754 BUG_ON(mddev
->delta_disks
!= 0);
6757 if (mddev
->private == NULL
)
6758 conf
= setup_conf(mddev
);
6760 conf
= mddev
->private;
6763 return PTR_ERR(conf
);
6765 conf
->min_offset_diff
= min_offset_diff
;
6766 mddev
->thread
= conf
->thread
;
6767 conf
->thread
= NULL
;
6768 mddev
->private = conf
;
6770 for (i
= 0; i
< conf
->raid_disks
&& conf
->previous_raid_disks
;
6772 rdev
= conf
->disks
[i
].rdev
;
6773 if (!rdev
&& conf
->disks
[i
].replacement
) {
6774 /* The replacement is all we have yet */
6775 rdev
= conf
->disks
[i
].replacement
;
6776 conf
->disks
[i
].replacement
= NULL
;
6777 clear_bit(Replacement
, &rdev
->flags
);
6778 conf
->disks
[i
].rdev
= rdev
;
6782 if (conf
->disks
[i
].replacement
&&
6783 conf
->reshape_progress
!= MaxSector
) {
6784 /* replacements and reshape simply do not mix. */
6785 printk(KERN_ERR
"md: cannot handle concurrent "
6786 "replacement and reshape.\n");
6789 if (test_bit(In_sync
, &rdev
->flags
)) {
6793 /* This disc is not fully in-sync. However if it
6794 * just stored parity (beyond the recovery_offset),
6795 * when we don't need to be concerned about the
6796 * array being dirty.
6797 * When reshape goes 'backwards', we never have
6798 * partially completed devices, so we only need
6799 * to worry about reshape going forwards.
6801 /* Hack because v0.91 doesn't store recovery_offset properly. */
6802 if (mddev
->major_version
== 0 &&
6803 mddev
->minor_version
> 90)
6804 rdev
->recovery_offset
= reshape_offset
;
6806 if (rdev
->recovery_offset
< reshape_offset
) {
6807 /* We need to check old and new layout */
6808 if (!only_parity(rdev
->raid_disk
,
6811 conf
->max_degraded
))
6814 if (!only_parity(rdev
->raid_disk
,
6816 conf
->previous_raid_disks
,
6817 conf
->max_degraded
))
6819 dirty_parity_disks
++;
6823 * 0 for a fully functional array, 1 or 2 for a degraded array.
6825 mddev
->degraded
= calc_degraded(conf
);
6827 if (has_failed(conf
)) {
6828 printk(KERN_ERR
"md/raid:%s: not enough operational devices"
6829 " (%d/%d failed)\n",
6830 mdname(mddev
), mddev
->degraded
, conf
->raid_disks
);
6834 /* device size must be a multiple of chunk size */
6835 mddev
->dev_sectors
&= ~(mddev
->chunk_sectors
- 1);
6836 mddev
->resync_max_sectors
= mddev
->dev_sectors
;
6838 if (mddev
->degraded
> dirty_parity_disks
&&
6839 mddev
->recovery_cp
!= MaxSector
) {
6840 if (mddev
->ok_start_degraded
)
6842 "md/raid:%s: starting dirty degraded array"
6843 " - data corruption possible.\n",
6847 "md/raid:%s: cannot start dirty degraded array.\n",
6853 if (mddev
->degraded
== 0)
6854 printk(KERN_INFO
"md/raid:%s: raid level %d active with %d out of %d"
6855 " devices, algorithm %d\n", mdname(mddev
), conf
->level
,
6856 mddev
->raid_disks
-mddev
->degraded
, mddev
->raid_disks
,
6859 printk(KERN_ALERT
"md/raid:%s: raid level %d active with %d"
6860 " out of %d devices, algorithm %d\n",
6861 mdname(mddev
), conf
->level
,
6862 mddev
->raid_disks
- mddev
->degraded
,
6863 mddev
->raid_disks
, mddev
->new_layout
);
6865 print_raid5_conf(conf
);
6867 if (conf
->reshape_progress
!= MaxSector
) {
6868 conf
->reshape_safe
= conf
->reshape_progress
;
6869 atomic_set(&conf
->reshape_stripes
, 0);
6870 clear_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
);
6871 clear_bit(MD_RECOVERY_CHECK
, &mddev
->recovery
);
6872 set_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
);
6873 set_bit(MD_RECOVERY_RUNNING
, &mddev
->recovery
);
6874 mddev
->sync_thread
= md_register_thread(md_do_sync
, mddev
,
6878 /* Ok, everything is just fine now */
6879 if (mddev
->to_remove
== &raid5_attrs_group
)
6880 mddev
->to_remove
= NULL
;
6881 else if (mddev
->kobj
.sd
&&
6882 sysfs_create_group(&mddev
->kobj
, &raid5_attrs_group
))
6884 "raid5: failed to create sysfs attributes for %s\n",
6886 md_set_array_sectors(mddev
, raid5_size(mddev
, 0, 0));
6890 bool discard_supported
= true;
6891 /* read-ahead size must cover two whole stripes, which
6892 * is 2 * (datadisks) * chunksize where 'n' is the
6893 * number of raid devices
6895 int data_disks
= conf
->previous_raid_disks
- conf
->max_degraded
;
6896 int stripe
= data_disks
*
6897 ((mddev
->chunk_sectors
<< 9) / PAGE_SIZE
);
6898 if (mddev
->queue
->backing_dev_info
.ra_pages
< 2 * stripe
)
6899 mddev
->queue
->backing_dev_info
.ra_pages
= 2 * stripe
;
6901 chunk_size
= mddev
->chunk_sectors
<< 9;
6902 blk_queue_io_min(mddev
->queue
, chunk_size
);
6903 blk_queue_io_opt(mddev
->queue
, chunk_size
*
6904 (conf
->raid_disks
- conf
->max_degraded
));
6905 mddev
->queue
->limits
.raid_partial_stripes_expensive
= 1;
6907 * We can only discard a whole stripe. It doesn't make sense to
6908 * discard data disk but write parity disk
6910 stripe
= stripe
* PAGE_SIZE
;
6911 /* Round up to power of 2, as discard handling
6912 * currently assumes that */
6913 while ((stripe
-1) & stripe
)
6914 stripe
= (stripe
| (stripe
-1)) + 1;
6915 mddev
->queue
->limits
.discard_alignment
= stripe
;
6916 mddev
->queue
->limits
.discard_granularity
= stripe
;
6918 * unaligned part of discard request will be ignored, so can't
6919 * guarantee discard_zeroes_data
6921 mddev
->queue
->limits
.discard_zeroes_data
= 0;
6923 blk_queue_max_write_same_sectors(mddev
->queue
, 0);
6925 rdev_for_each(rdev
, mddev
) {
6926 disk_stack_limits(mddev
->gendisk
, rdev
->bdev
,
6927 rdev
->data_offset
<< 9);
6928 disk_stack_limits(mddev
->gendisk
, rdev
->bdev
,
6929 rdev
->new_data_offset
<< 9);
6931 * discard_zeroes_data is required, otherwise data
6932 * could be lost. Consider a scenario: discard a stripe
6933 * (the stripe could be inconsistent if
6934 * discard_zeroes_data is 0); write one disk of the
6935 * stripe (the stripe could be inconsistent again
6936 * depending on which disks are used to calculate
6937 * parity); the disk is broken; The stripe data of this
6940 if (!blk_queue_discard(bdev_get_queue(rdev
->bdev
)) ||
6941 !bdev_get_queue(rdev
->bdev
)->
6942 limits
.discard_zeroes_data
)
6943 discard_supported
= false;
6944 /* Unfortunately, discard_zeroes_data is not currently
6945 * a guarantee - just a hint. So we only allow DISCARD
6946 * if the sysadmin has confirmed that only safe devices
6947 * are in use by setting a module parameter.
6949 if (!devices_handle_discard_safely
) {
6950 if (discard_supported
) {
6951 pr_info("md/raid456: discard support disabled due to uncertainty.\n");
6952 pr_info("Set raid456.devices_handle_discard_safely=Y to override.\n");
6954 discard_supported
= false;
6958 if (discard_supported
&&
6959 mddev
->queue
->limits
.max_discard_sectors
>= stripe
&&
6960 mddev
->queue
->limits
.discard_granularity
>= stripe
)
6961 queue_flag_set_unlocked(QUEUE_FLAG_DISCARD
,
6964 queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD
,
6970 md_unregister_thread(&mddev
->thread
);
6971 print_raid5_conf(conf
);
6973 mddev
->private = NULL
;
6974 printk(KERN_ALERT
"md/raid:%s: failed to run raid set.\n", mdname(mddev
));
6978 static void raid5_free(struct mddev
*mddev
, void *priv
)
6980 struct r5conf
*conf
= priv
;
6983 mddev
->to_remove
= &raid5_attrs_group
;
6986 static void status(struct seq_file
*seq
, struct mddev
*mddev
)
6988 struct r5conf
*conf
= mddev
->private;
6991 seq_printf(seq
, " level %d, %dk chunk, algorithm %d", mddev
->level
,
6992 mddev
->chunk_sectors
/ 2, mddev
->layout
);
6993 seq_printf (seq
, " [%d/%d] [", conf
->raid_disks
, conf
->raid_disks
- mddev
->degraded
);
6994 for (i
= 0; i
< conf
->raid_disks
; i
++)
6995 seq_printf (seq
, "%s",
6996 conf
->disks
[i
].rdev
&&
6997 test_bit(In_sync
, &conf
->disks
[i
].rdev
->flags
) ? "U" : "_");
6998 seq_printf (seq
, "]");
7001 static void print_raid5_conf (struct r5conf
*conf
)
7004 struct disk_info
*tmp
;
7006 printk(KERN_DEBUG
"RAID conf printout:\n");
7008 printk("(conf==NULL)\n");
7011 printk(KERN_DEBUG
" --- level:%d rd:%d wd:%d\n", conf
->level
,
7013 conf
->raid_disks
- conf
->mddev
->degraded
);
7015 for (i
= 0; i
< conf
->raid_disks
; i
++) {
7016 char b
[BDEVNAME_SIZE
];
7017 tmp
= conf
->disks
+ i
;
7019 printk(KERN_DEBUG
" disk %d, o:%d, dev:%s\n",
7020 i
, !test_bit(Faulty
, &tmp
->rdev
->flags
),
7021 bdevname(tmp
->rdev
->bdev
, b
));
7025 static int raid5_spare_active(struct mddev
*mddev
)
7028 struct r5conf
*conf
= mddev
->private;
7029 struct disk_info
*tmp
;
7031 unsigned long flags
;
7033 for (i
= 0; i
< conf
->raid_disks
; i
++) {
7034 tmp
= conf
->disks
+ i
;
7035 if (tmp
->replacement
7036 && tmp
->replacement
->recovery_offset
== MaxSector
7037 && !test_bit(Faulty
, &tmp
->replacement
->flags
)
7038 && !test_and_set_bit(In_sync
, &tmp
->replacement
->flags
)) {
7039 /* Replacement has just become active. */
7041 || !test_and_clear_bit(In_sync
, &tmp
->rdev
->flags
))
7044 /* Replaced device not technically faulty,
7045 * but we need to be sure it gets removed
7046 * and never re-added.
7048 set_bit(Faulty
, &tmp
->rdev
->flags
);
7049 sysfs_notify_dirent_safe(
7050 tmp
->rdev
->sysfs_state
);
7052 sysfs_notify_dirent_safe(tmp
->replacement
->sysfs_state
);
7053 } else if (tmp
->rdev
7054 && tmp
->rdev
->recovery_offset
== MaxSector
7055 && !test_bit(Faulty
, &tmp
->rdev
->flags
)
7056 && !test_and_set_bit(In_sync
, &tmp
->rdev
->flags
)) {
7058 sysfs_notify_dirent_safe(tmp
->rdev
->sysfs_state
);
7061 spin_lock_irqsave(&conf
->device_lock
, flags
);
7062 mddev
->degraded
= calc_degraded(conf
);
7063 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
7064 print_raid5_conf(conf
);
7068 static int raid5_remove_disk(struct mddev
*mddev
, struct md_rdev
*rdev
)
7070 struct r5conf
*conf
= mddev
->private;
7072 int number
= rdev
->raid_disk
;
7073 struct md_rdev
**rdevp
;
7074 struct disk_info
*p
= conf
->disks
+ number
;
7076 print_raid5_conf(conf
);
7077 if (rdev
== p
->rdev
)
7079 else if (rdev
== p
->replacement
)
7080 rdevp
= &p
->replacement
;
7084 if (number
>= conf
->raid_disks
&&
7085 conf
->reshape_progress
== MaxSector
)
7086 clear_bit(In_sync
, &rdev
->flags
);
7088 if (test_bit(In_sync
, &rdev
->flags
) ||
7089 atomic_read(&rdev
->nr_pending
)) {
7093 /* Only remove non-faulty devices if recovery
7096 if (!test_bit(Faulty
, &rdev
->flags
) &&
7097 mddev
->recovery_disabled
!= conf
->recovery_disabled
&&
7098 !has_failed(conf
) &&
7099 (!p
->replacement
|| p
->replacement
== rdev
) &&
7100 number
< conf
->raid_disks
) {
7106 if (atomic_read(&rdev
->nr_pending
)) {
7107 /* lost the race, try later */
7110 } else if (p
->replacement
) {
7111 /* We must have just cleared 'rdev' */
7112 p
->rdev
= p
->replacement
;
7113 clear_bit(Replacement
, &p
->replacement
->flags
);
7114 smp_mb(); /* Make sure other CPUs may see both as identical
7115 * but will never see neither - if they are careful
7117 p
->replacement
= NULL
;
7118 clear_bit(WantReplacement
, &rdev
->flags
);
7120 /* We might have just removed the Replacement as faulty-
7121 * clear the bit just in case
7123 clear_bit(WantReplacement
, &rdev
->flags
);
7126 print_raid5_conf(conf
);
7130 static int raid5_add_disk(struct mddev
*mddev
, struct md_rdev
*rdev
)
7132 struct r5conf
*conf
= mddev
->private;
7135 struct disk_info
*p
;
7137 int last
= conf
->raid_disks
- 1;
7139 if (mddev
->recovery_disabled
== conf
->recovery_disabled
)
7142 if (rdev
->saved_raid_disk
< 0 && has_failed(conf
))
7143 /* no point adding a device */
7146 if (rdev
->raid_disk
>= 0)
7147 first
= last
= rdev
->raid_disk
;
7150 * find the disk ... but prefer rdev->saved_raid_disk
7153 if (rdev
->saved_raid_disk
>= 0 &&
7154 rdev
->saved_raid_disk
>= first
&&
7155 conf
->disks
[rdev
->saved_raid_disk
].rdev
== NULL
)
7156 first
= rdev
->saved_raid_disk
;
7158 for (disk
= first
; disk
<= last
; disk
++) {
7159 p
= conf
->disks
+ disk
;
7160 if (p
->rdev
== NULL
) {
7161 clear_bit(In_sync
, &rdev
->flags
);
7162 rdev
->raid_disk
= disk
;
7164 if (rdev
->saved_raid_disk
!= disk
)
7166 rcu_assign_pointer(p
->rdev
, rdev
);
7170 for (disk
= first
; disk
<= last
; disk
++) {
7171 p
= conf
->disks
+ disk
;
7172 if (test_bit(WantReplacement
, &p
->rdev
->flags
) &&
7173 p
->replacement
== NULL
) {
7174 clear_bit(In_sync
, &rdev
->flags
);
7175 set_bit(Replacement
, &rdev
->flags
);
7176 rdev
->raid_disk
= disk
;
7179 rcu_assign_pointer(p
->replacement
, rdev
);
7184 print_raid5_conf(conf
);
7188 static int raid5_resize(struct mddev
*mddev
, sector_t sectors
)
7190 /* no resync is happening, and there is enough space
7191 * on all devices, so we can resize.
7192 * We need to make sure resync covers any new space.
7193 * If the array is shrinking we should possibly wait until
7194 * any io in the removed space completes, but it hardly seems
7198 sectors
&= ~((sector_t
)mddev
->chunk_sectors
- 1);
7199 newsize
= raid5_size(mddev
, sectors
, mddev
->raid_disks
);
7200 if (mddev
->external_size
&&
7201 mddev
->array_sectors
> newsize
)
7203 if (mddev
->bitmap
) {
7204 int ret
= bitmap_resize(mddev
->bitmap
, sectors
, 0, 0);
7208 md_set_array_sectors(mddev
, newsize
);
7209 set_capacity(mddev
->gendisk
, mddev
->array_sectors
);
7210 revalidate_disk(mddev
->gendisk
);
7211 if (sectors
> mddev
->dev_sectors
&&
7212 mddev
->recovery_cp
> mddev
->dev_sectors
) {
7213 mddev
->recovery_cp
= mddev
->dev_sectors
;
7214 set_bit(MD_RECOVERY_NEEDED
, &mddev
->recovery
);
7216 mddev
->dev_sectors
= sectors
;
7217 mddev
->resync_max_sectors
= sectors
;
7221 static int check_stripe_cache(struct mddev
*mddev
)
7223 /* Can only proceed if there are plenty of stripe_heads.
7224 * We need a minimum of one full stripe,, and for sensible progress
7225 * it is best to have about 4 times that.
7226 * If we require 4 times, then the default 256 4K stripe_heads will
7227 * allow for chunk sizes up to 256K, which is probably OK.
7228 * If the chunk size is greater, user-space should request more
7229 * stripe_heads first.
7231 struct r5conf
*conf
= mddev
->private;
7232 if (((mddev
->chunk_sectors
<< 9) / STRIPE_SIZE
) * 4
7233 > conf
->min_nr_stripes
||
7234 ((mddev
->new_chunk_sectors
<< 9) / STRIPE_SIZE
) * 4
7235 > conf
->min_nr_stripes
) {
7236 printk(KERN_WARNING
"md/raid:%s: reshape: not enough stripes. Needed %lu\n",
7238 ((max(mddev
->chunk_sectors
, mddev
->new_chunk_sectors
) << 9)
7245 static int check_reshape(struct mddev
*mddev
)
7247 struct r5conf
*conf
= mddev
->private;
7249 if (mddev
->delta_disks
== 0 &&
7250 mddev
->new_layout
== mddev
->layout
&&
7251 mddev
->new_chunk_sectors
== mddev
->chunk_sectors
)
7252 return 0; /* nothing to do */
7253 if (has_failed(conf
))
7255 if (mddev
->delta_disks
< 0 && mddev
->reshape_position
== MaxSector
) {
7256 /* We might be able to shrink, but the devices must
7257 * be made bigger first.
7258 * For raid6, 4 is the minimum size.
7259 * Otherwise 2 is the minimum
7262 if (mddev
->level
== 6)
7264 if (mddev
->raid_disks
+ mddev
->delta_disks
< min
)
7268 if (!check_stripe_cache(mddev
))
7271 if (mddev
->new_chunk_sectors
> mddev
->chunk_sectors
||
7272 mddev
->delta_disks
> 0)
7273 if (resize_chunks(conf
,
7274 conf
->previous_raid_disks
7275 + max(0, mddev
->delta_disks
),
7276 max(mddev
->new_chunk_sectors
,
7277 mddev
->chunk_sectors
)
7280 return resize_stripes(conf
, (conf
->previous_raid_disks
7281 + mddev
->delta_disks
));
7284 static int raid5_start_reshape(struct mddev
*mddev
)
7286 struct r5conf
*conf
= mddev
->private;
7287 struct md_rdev
*rdev
;
7289 unsigned long flags
;
7291 if (test_bit(MD_RECOVERY_RUNNING
, &mddev
->recovery
))
7294 if (!check_stripe_cache(mddev
))
7297 if (has_failed(conf
))
7300 rdev_for_each(rdev
, mddev
) {
7301 if (!test_bit(In_sync
, &rdev
->flags
)
7302 && !test_bit(Faulty
, &rdev
->flags
))
7306 if (spares
- mddev
->degraded
< mddev
->delta_disks
- conf
->max_degraded
)
7307 /* Not enough devices even to make a degraded array
7312 /* Refuse to reduce size of the array. Any reductions in
7313 * array size must be through explicit setting of array_size
7316 if (raid5_size(mddev
, 0, conf
->raid_disks
+ mddev
->delta_disks
)
7317 < mddev
->array_sectors
) {
7318 printk(KERN_ERR
"md/raid:%s: array size must be reduced "
7319 "before number of disks\n", mdname(mddev
));
7323 atomic_set(&conf
->reshape_stripes
, 0);
7324 spin_lock_irq(&conf
->device_lock
);
7325 write_seqcount_begin(&conf
->gen_lock
);
7326 conf
->previous_raid_disks
= conf
->raid_disks
;
7327 conf
->raid_disks
+= mddev
->delta_disks
;
7328 conf
->prev_chunk_sectors
= conf
->chunk_sectors
;
7329 conf
->chunk_sectors
= mddev
->new_chunk_sectors
;
7330 conf
->prev_algo
= conf
->algorithm
;
7331 conf
->algorithm
= mddev
->new_layout
;
7333 /* Code that selects data_offset needs to see the generation update
7334 * if reshape_progress has been set - so a memory barrier needed.
7337 if (mddev
->reshape_backwards
)
7338 conf
->reshape_progress
= raid5_size(mddev
, 0, 0);
7340 conf
->reshape_progress
= 0;
7341 conf
->reshape_safe
= conf
->reshape_progress
;
7342 write_seqcount_end(&conf
->gen_lock
);
7343 spin_unlock_irq(&conf
->device_lock
);
7345 /* Now make sure any requests that proceeded on the assumption
7346 * the reshape wasn't running - like Discard or Read - have
7349 mddev_suspend(mddev
);
7350 mddev_resume(mddev
);
7352 /* Add some new drives, as many as will fit.
7353 * We know there are enough to make the newly sized array work.
7354 * Don't add devices if we are reducing the number of
7355 * devices in the array. This is because it is not possible
7356 * to correctly record the "partially reconstructed" state of
7357 * such devices during the reshape and confusion could result.
7359 if (mddev
->delta_disks
>= 0) {
7360 rdev_for_each(rdev
, mddev
)
7361 if (rdev
->raid_disk
< 0 &&
7362 !test_bit(Faulty
, &rdev
->flags
)) {
7363 if (raid5_add_disk(mddev
, rdev
) == 0) {
7365 >= conf
->previous_raid_disks
)
7366 set_bit(In_sync
, &rdev
->flags
);
7368 rdev
->recovery_offset
= 0;
7370 if (sysfs_link_rdev(mddev
, rdev
))
7371 /* Failure here is OK */;
7373 } else if (rdev
->raid_disk
>= conf
->previous_raid_disks
7374 && !test_bit(Faulty
, &rdev
->flags
)) {
7375 /* This is a spare that was manually added */
7376 set_bit(In_sync
, &rdev
->flags
);
7379 /* When a reshape changes the number of devices,
7380 * ->degraded is measured against the larger of the
7381 * pre and post number of devices.
7383 spin_lock_irqsave(&conf
->device_lock
, flags
);
7384 mddev
->degraded
= calc_degraded(conf
);
7385 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
7387 mddev
->raid_disks
= conf
->raid_disks
;
7388 mddev
->reshape_position
= conf
->reshape_progress
;
7389 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
7391 clear_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
);
7392 clear_bit(MD_RECOVERY_CHECK
, &mddev
->recovery
);
7393 clear_bit(MD_RECOVERY_DONE
, &mddev
->recovery
);
7394 set_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
);
7395 set_bit(MD_RECOVERY_RUNNING
, &mddev
->recovery
);
7396 mddev
->sync_thread
= md_register_thread(md_do_sync
, mddev
,
7398 if (!mddev
->sync_thread
) {
7399 mddev
->recovery
= 0;
7400 spin_lock_irq(&conf
->device_lock
);
7401 write_seqcount_begin(&conf
->gen_lock
);
7402 mddev
->raid_disks
= conf
->raid_disks
= conf
->previous_raid_disks
;
7403 mddev
->new_chunk_sectors
=
7404 conf
->chunk_sectors
= conf
->prev_chunk_sectors
;
7405 mddev
->new_layout
= conf
->algorithm
= conf
->prev_algo
;
7406 rdev_for_each(rdev
, mddev
)
7407 rdev
->new_data_offset
= rdev
->data_offset
;
7409 conf
->generation
--;
7410 conf
->reshape_progress
= MaxSector
;
7411 mddev
->reshape_position
= MaxSector
;
7412 write_seqcount_end(&conf
->gen_lock
);
7413 spin_unlock_irq(&conf
->device_lock
);
7416 conf
->reshape_checkpoint
= jiffies
;
7417 md_wakeup_thread(mddev
->sync_thread
);
7418 md_new_event(mddev
);
7422 /* This is called from the reshape thread and should make any
7423 * changes needed in 'conf'
7425 static void end_reshape(struct r5conf
*conf
)
7428 if (!test_bit(MD_RECOVERY_INTR
, &conf
->mddev
->recovery
)) {
7429 struct md_rdev
*rdev
;
7431 spin_lock_irq(&conf
->device_lock
);
7432 conf
->previous_raid_disks
= conf
->raid_disks
;
7433 rdev_for_each(rdev
, conf
->mddev
)
7434 rdev
->data_offset
= rdev
->new_data_offset
;
7436 conf
->reshape_progress
= MaxSector
;
7437 spin_unlock_irq(&conf
->device_lock
);
7438 wake_up(&conf
->wait_for_overlap
);
7440 /* read-ahead size must cover two whole stripes, which is
7441 * 2 * (datadisks) * chunksize where 'n' is the number of raid devices
7443 if (conf
->mddev
->queue
) {
7444 int data_disks
= conf
->raid_disks
- conf
->max_degraded
;
7445 int stripe
= data_disks
* ((conf
->chunk_sectors
<< 9)
7447 if (conf
->mddev
->queue
->backing_dev_info
.ra_pages
< 2 * stripe
)
7448 conf
->mddev
->queue
->backing_dev_info
.ra_pages
= 2 * stripe
;
7453 /* This is called from the raid5d thread with mddev_lock held.
7454 * It makes config changes to the device.
7456 static void raid5_finish_reshape(struct mddev
*mddev
)
7458 struct r5conf
*conf
= mddev
->private;
7460 if (!test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
)) {
7462 if (mddev
->delta_disks
> 0) {
7463 md_set_array_sectors(mddev
, raid5_size(mddev
, 0, 0));
7464 set_capacity(mddev
->gendisk
, mddev
->array_sectors
);
7465 revalidate_disk(mddev
->gendisk
);
7468 spin_lock_irq(&conf
->device_lock
);
7469 mddev
->degraded
= calc_degraded(conf
);
7470 spin_unlock_irq(&conf
->device_lock
);
7471 for (d
= conf
->raid_disks
;
7472 d
< conf
->raid_disks
- mddev
->delta_disks
;
7474 struct md_rdev
*rdev
= conf
->disks
[d
].rdev
;
7476 clear_bit(In_sync
, &rdev
->flags
);
7477 rdev
= conf
->disks
[d
].replacement
;
7479 clear_bit(In_sync
, &rdev
->flags
);
7482 mddev
->layout
= conf
->algorithm
;
7483 mddev
->chunk_sectors
= conf
->chunk_sectors
;
7484 mddev
->reshape_position
= MaxSector
;
7485 mddev
->delta_disks
= 0;
7486 mddev
->reshape_backwards
= 0;
7490 static void raid5_quiesce(struct mddev
*mddev
, int state
)
7492 struct r5conf
*conf
= mddev
->private;
7495 case 2: /* resume for a suspend */
7496 wake_up(&conf
->wait_for_overlap
);
7499 case 1: /* stop all writes */
7500 lock_all_device_hash_locks_irq(conf
);
7501 /* '2' tells resync/reshape to pause so that all
7502 * active stripes can drain
7505 wait_event_cmd(conf
->wait_for_quiescent
,
7506 atomic_read(&conf
->active_stripes
) == 0 &&
7507 atomic_read(&conf
->active_aligned_reads
) == 0,
7508 unlock_all_device_hash_locks_irq(conf
),
7509 lock_all_device_hash_locks_irq(conf
));
7511 unlock_all_device_hash_locks_irq(conf
);
7512 /* allow reshape to continue */
7513 wake_up(&conf
->wait_for_overlap
);
7516 case 0: /* re-enable writes */
7517 lock_all_device_hash_locks_irq(conf
);
7519 wake_up(&conf
->wait_for_quiescent
);
7520 wake_up(&conf
->wait_for_overlap
);
7521 unlock_all_device_hash_locks_irq(conf
);
7526 static void *raid45_takeover_raid0(struct mddev
*mddev
, int level
)
7528 struct r0conf
*raid0_conf
= mddev
->private;
7531 /* for raid0 takeover only one zone is supported */
7532 if (raid0_conf
->nr_strip_zones
> 1) {
7533 printk(KERN_ERR
"md/raid:%s: cannot takeover raid0 with more than one zone.\n",
7535 return ERR_PTR(-EINVAL
);
7538 sectors
= raid0_conf
->strip_zone
[0].zone_end
;
7539 sector_div(sectors
, raid0_conf
->strip_zone
[0].nb_dev
);
7540 mddev
->dev_sectors
= sectors
;
7541 mddev
->new_level
= level
;
7542 mddev
->new_layout
= ALGORITHM_PARITY_N
;
7543 mddev
->new_chunk_sectors
= mddev
->chunk_sectors
;
7544 mddev
->raid_disks
+= 1;
7545 mddev
->delta_disks
= 1;
7546 /* make sure it will be not marked as dirty */
7547 mddev
->recovery_cp
= MaxSector
;
7549 return setup_conf(mddev
);
7552 static void *raid5_takeover_raid1(struct mddev
*mddev
)
7556 if (mddev
->raid_disks
!= 2 ||
7557 mddev
->degraded
> 1)
7558 return ERR_PTR(-EINVAL
);
7560 /* Should check if there are write-behind devices? */
7562 chunksect
= 64*2; /* 64K by default */
7564 /* The array must be an exact multiple of chunksize */
7565 while (chunksect
&& (mddev
->array_sectors
& (chunksect
-1)))
7568 if ((chunksect
<<9) < STRIPE_SIZE
)
7569 /* array size does not allow a suitable chunk size */
7570 return ERR_PTR(-EINVAL
);
7572 mddev
->new_level
= 5;
7573 mddev
->new_layout
= ALGORITHM_LEFT_SYMMETRIC
;
7574 mddev
->new_chunk_sectors
= chunksect
;
7576 return setup_conf(mddev
);
7579 static void *raid5_takeover_raid6(struct mddev
*mddev
)
7583 switch (mddev
->layout
) {
7584 case ALGORITHM_LEFT_ASYMMETRIC_6
:
7585 new_layout
= ALGORITHM_LEFT_ASYMMETRIC
;
7587 case ALGORITHM_RIGHT_ASYMMETRIC_6
:
7588 new_layout
= ALGORITHM_RIGHT_ASYMMETRIC
;
7590 case ALGORITHM_LEFT_SYMMETRIC_6
:
7591 new_layout
= ALGORITHM_LEFT_SYMMETRIC
;
7593 case ALGORITHM_RIGHT_SYMMETRIC_6
:
7594 new_layout
= ALGORITHM_RIGHT_SYMMETRIC
;
7596 case ALGORITHM_PARITY_0_6
:
7597 new_layout
= ALGORITHM_PARITY_0
;
7599 case ALGORITHM_PARITY_N
:
7600 new_layout
= ALGORITHM_PARITY_N
;
7603 return ERR_PTR(-EINVAL
);
7605 mddev
->new_level
= 5;
7606 mddev
->new_layout
= new_layout
;
7607 mddev
->delta_disks
= -1;
7608 mddev
->raid_disks
-= 1;
7609 return setup_conf(mddev
);
7612 static int raid5_check_reshape(struct mddev
*mddev
)
7614 /* For a 2-drive array, the layout and chunk size can be changed
7615 * immediately as not restriping is needed.
7616 * For larger arrays we record the new value - after validation
7617 * to be used by a reshape pass.
7619 struct r5conf
*conf
= mddev
->private;
7620 int new_chunk
= mddev
->new_chunk_sectors
;
7622 if (mddev
->new_layout
>= 0 && !algorithm_valid_raid5(mddev
->new_layout
))
7624 if (new_chunk
> 0) {
7625 if (!is_power_of_2(new_chunk
))
7627 if (new_chunk
< (PAGE_SIZE
>>9))
7629 if (mddev
->array_sectors
& (new_chunk
-1))
7630 /* not factor of array size */
7634 /* They look valid */
7636 if (mddev
->raid_disks
== 2) {
7637 /* can make the change immediately */
7638 if (mddev
->new_layout
>= 0) {
7639 conf
->algorithm
= mddev
->new_layout
;
7640 mddev
->layout
= mddev
->new_layout
;
7642 if (new_chunk
> 0) {
7643 conf
->chunk_sectors
= new_chunk
;
7644 mddev
->chunk_sectors
= new_chunk
;
7646 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
7647 md_wakeup_thread(mddev
->thread
);
7649 return check_reshape(mddev
);
7652 static int raid6_check_reshape(struct mddev
*mddev
)
7654 int new_chunk
= mddev
->new_chunk_sectors
;
7656 if (mddev
->new_layout
>= 0 && !algorithm_valid_raid6(mddev
->new_layout
))
7658 if (new_chunk
> 0) {
7659 if (!is_power_of_2(new_chunk
))
7661 if (new_chunk
< (PAGE_SIZE
>> 9))
7663 if (mddev
->array_sectors
& (new_chunk
-1))
7664 /* not factor of array size */
7668 /* They look valid */
7669 return check_reshape(mddev
);
7672 static void *raid5_takeover(struct mddev
*mddev
)
7674 /* raid5 can take over:
7675 * raid0 - if there is only one strip zone - make it a raid4 layout
7676 * raid1 - if there are two drives. We need to know the chunk size
7677 * raid4 - trivial - just use a raid4 layout.
7678 * raid6 - Providing it is a *_6 layout
7680 if (mddev
->level
== 0)
7681 return raid45_takeover_raid0(mddev
, 5);
7682 if (mddev
->level
== 1)
7683 return raid5_takeover_raid1(mddev
);
7684 if (mddev
->level
== 4) {
7685 mddev
->new_layout
= ALGORITHM_PARITY_N
;
7686 mddev
->new_level
= 5;
7687 return setup_conf(mddev
);
7689 if (mddev
->level
== 6)
7690 return raid5_takeover_raid6(mddev
);
7692 return ERR_PTR(-EINVAL
);
7695 static void *raid4_takeover(struct mddev
*mddev
)
7697 /* raid4 can take over:
7698 * raid0 - if there is only one strip zone
7699 * raid5 - if layout is right
7701 if (mddev
->level
== 0)
7702 return raid45_takeover_raid0(mddev
, 4);
7703 if (mddev
->level
== 5 &&
7704 mddev
->layout
== ALGORITHM_PARITY_N
) {
7705 mddev
->new_layout
= 0;
7706 mddev
->new_level
= 4;
7707 return setup_conf(mddev
);
7709 return ERR_PTR(-EINVAL
);
7712 static struct md_personality raid5_personality
;
7714 static void *raid6_takeover(struct mddev
*mddev
)
7716 /* Currently can only take over a raid5. We map the
7717 * personality to an equivalent raid6 personality
7718 * with the Q block at the end.
7722 if (mddev
->pers
!= &raid5_personality
)
7723 return ERR_PTR(-EINVAL
);
7724 if (mddev
->degraded
> 1)
7725 return ERR_PTR(-EINVAL
);
7726 if (mddev
->raid_disks
> 253)
7727 return ERR_PTR(-EINVAL
);
7728 if (mddev
->raid_disks
< 3)
7729 return ERR_PTR(-EINVAL
);
7731 switch (mddev
->layout
) {
7732 case ALGORITHM_LEFT_ASYMMETRIC
:
7733 new_layout
= ALGORITHM_LEFT_ASYMMETRIC_6
;
7735 case ALGORITHM_RIGHT_ASYMMETRIC
:
7736 new_layout
= ALGORITHM_RIGHT_ASYMMETRIC_6
;
7738 case ALGORITHM_LEFT_SYMMETRIC
:
7739 new_layout
= ALGORITHM_LEFT_SYMMETRIC_6
;
7741 case ALGORITHM_RIGHT_SYMMETRIC
:
7742 new_layout
= ALGORITHM_RIGHT_SYMMETRIC_6
;
7744 case ALGORITHM_PARITY_0
:
7745 new_layout
= ALGORITHM_PARITY_0_6
;
7747 case ALGORITHM_PARITY_N
:
7748 new_layout
= ALGORITHM_PARITY_N
;
7751 return ERR_PTR(-EINVAL
);
7753 mddev
->new_level
= 6;
7754 mddev
->new_layout
= new_layout
;
7755 mddev
->delta_disks
= 1;
7756 mddev
->raid_disks
+= 1;
7757 return setup_conf(mddev
);
7760 static struct md_personality raid6_personality
=
7764 .owner
= THIS_MODULE
,
7765 .make_request
= make_request
,
7769 .error_handler
= error
,
7770 .hot_add_disk
= raid5_add_disk
,
7771 .hot_remove_disk
= raid5_remove_disk
,
7772 .spare_active
= raid5_spare_active
,
7773 .sync_request
= sync_request
,
7774 .resize
= raid5_resize
,
7776 .check_reshape
= raid6_check_reshape
,
7777 .start_reshape
= raid5_start_reshape
,
7778 .finish_reshape
= raid5_finish_reshape
,
7779 .quiesce
= raid5_quiesce
,
7780 .takeover
= raid6_takeover
,
7781 .congested
= raid5_congested
,
7782 .mergeable_bvec
= raid5_mergeable_bvec
,
7784 static struct md_personality raid5_personality
=
7788 .owner
= THIS_MODULE
,
7789 .make_request
= make_request
,
7793 .error_handler
= error
,
7794 .hot_add_disk
= raid5_add_disk
,
7795 .hot_remove_disk
= raid5_remove_disk
,
7796 .spare_active
= raid5_spare_active
,
7797 .sync_request
= sync_request
,
7798 .resize
= raid5_resize
,
7800 .check_reshape
= raid5_check_reshape
,
7801 .start_reshape
= raid5_start_reshape
,
7802 .finish_reshape
= raid5_finish_reshape
,
7803 .quiesce
= raid5_quiesce
,
7804 .takeover
= raid5_takeover
,
7805 .congested
= raid5_congested
,
7806 .mergeable_bvec
= raid5_mergeable_bvec
,
7809 static struct md_personality raid4_personality
=
7813 .owner
= THIS_MODULE
,
7814 .make_request
= make_request
,
7818 .error_handler
= error
,
7819 .hot_add_disk
= raid5_add_disk
,
7820 .hot_remove_disk
= raid5_remove_disk
,
7821 .spare_active
= raid5_spare_active
,
7822 .sync_request
= sync_request
,
7823 .resize
= raid5_resize
,
7825 .check_reshape
= raid5_check_reshape
,
7826 .start_reshape
= raid5_start_reshape
,
7827 .finish_reshape
= raid5_finish_reshape
,
7828 .quiesce
= raid5_quiesce
,
7829 .takeover
= raid4_takeover
,
7830 .congested
= raid5_congested
,
7831 .mergeable_bvec
= raid5_mergeable_bvec
,
7834 static int __init
raid5_init(void)
7836 raid5_wq
= alloc_workqueue("raid5wq",
7837 WQ_UNBOUND
|WQ_MEM_RECLAIM
|WQ_CPU_INTENSIVE
|WQ_SYSFS
, 0);
7840 register_md_personality(&raid6_personality
);
7841 register_md_personality(&raid5_personality
);
7842 register_md_personality(&raid4_personality
);
7846 static void raid5_exit(void)
7848 unregister_md_personality(&raid6_personality
);
7849 unregister_md_personality(&raid5_personality
);
7850 unregister_md_personality(&raid4_personality
);
7851 destroy_workqueue(raid5_wq
);
7854 module_init(raid5_init
);
7855 module_exit(raid5_exit
);
7856 MODULE_LICENSE("GPL");
7857 MODULE_DESCRIPTION("RAID4/5/6 (striping with parity) personality for MD");
7858 MODULE_ALIAS("md-personality-4"); /* RAID5 */
7859 MODULE_ALIAS("md-raid5");
7860 MODULE_ALIAS("md-raid4");
7861 MODULE_ALIAS("md-level-5");
7862 MODULE_ALIAS("md-level-4");
7863 MODULE_ALIAS("md-personality-8"); /* RAID6 */
7864 MODULE_ALIAS("md-raid6");
7865 MODULE_ALIAS("md-level-6");
7867 /* This used to be two separate modules, they were: */
7868 MODULE_ALIAS("raid5");
7869 MODULE_ALIAS("raid6");