2 * raid5.c : Multiple Devices driver for Linux
3 * Copyright (C) 1996, 1997 Ingo Molnar, Miguel de Icaza, Gadi Oxman
4 * Copyright (C) 1999, 2000 Ingo Molnar
5 * Copyright (C) 2002, 2003 H. Peter Anvin
7 * RAID-4/5/6 management functions.
8 * Thanks to Penguin Computing for making the RAID-6 development possible
9 * by donating a test server!
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2, or (at your option)
16 * You should have received a copy of the GNU General Public License
17 * (for example /usr/src/linux/COPYING); if not, write to the Free
18 * Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24 * The sequencing for updating the bitmap reliably is a little
25 * subtle (and I got it wrong the first time) so it deserves some
28 * We group bitmap updates into batches. Each batch has a number.
29 * We may write out several batches at once, but that isn't very important.
30 * conf->seq_write is the number of the last batch successfully written.
31 * conf->seq_flush is the number of the last batch that was closed to
33 * When we discover that we will need to write to any block in a stripe
34 * (in add_stripe_bio) we update the in-memory bitmap and record in sh->bm_seq
35 * the number of the batch it will be in. This is seq_flush+1.
36 * When we are ready to do a write, if that batch hasn't been written yet,
37 * we plug the array and queue the stripe for later.
38 * When an unplug happens, we increment bm_flush, thus closing the current
40 * When we notice that bm_flush > bm_write, we write out all pending updates
41 * to the bitmap, and advance bm_write to where bm_flush was.
42 * This may occasionally write a bit out twice, but is sure never to
46 #include <linux/blkdev.h>
47 #include <linux/kthread.h>
48 #include <linux/raid/pq.h>
49 #include <linux/async_tx.h>
50 #include <linux/module.h>
51 #include <linux/async.h>
52 #include <linux/seq_file.h>
53 #include <linux/cpu.h>
54 #include <linux/slab.h>
55 #include <linux/ratelimit.h>
56 #include <linux/nodemask.h>
57 #include <linux/flex_array.h>
58 #include <trace/events/block.h>
65 #define cpu_to_group(cpu) cpu_to_node(cpu)
66 #define ANY_GROUP NUMA_NO_NODE
68 static bool devices_handle_discard_safely
= false;
69 module_param(devices_handle_discard_safely
, bool, 0644);
70 MODULE_PARM_DESC(devices_handle_discard_safely
,
71 "Set to Y if all devices in each array reliably return zeroes on reads from discarded regions");
72 static struct workqueue_struct
*raid5_wq
;
77 #define NR_STRIPES 256
78 #define STRIPE_SIZE PAGE_SIZE
79 #define STRIPE_SHIFT (PAGE_SHIFT - 9)
80 #define STRIPE_SECTORS (STRIPE_SIZE>>9)
81 #define IO_THRESHOLD 1
82 #define BYPASS_THRESHOLD 1
83 #define NR_HASH (PAGE_SIZE / sizeof(struct hlist_head))
84 #define HASH_MASK (NR_HASH - 1)
85 #define MAX_STRIPE_BATCH 8
87 static inline struct hlist_head
*stripe_hash(struct r5conf
*conf
, sector_t sect
)
89 int hash
= (sect
>> STRIPE_SHIFT
) & HASH_MASK
;
90 return &conf
->stripe_hashtbl
[hash
];
93 static inline int stripe_hash_locks_hash(sector_t sect
)
95 return (sect
>> STRIPE_SHIFT
) & STRIPE_HASH_LOCKS_MASK
;
98 static inline void lock_device_hash_lock(struct r5conf
*conf
, int hash
)
100 spin_lock_irq(conf
->hash_locks
+ hash
);
101 spin_lock(&conf
->device_lock
);
104 static inline void unlock_device_hash_lock(struct r5conf
*conf
, int hash
)
106 spin_unlock(&conf
->device_lock
);
107 spin_unlock_irq(conf
->hash_locks
+ hash
);
110 static inline void lock_all_device_hash_locks_irq(struct r5conf
*conf
)
114 spin_lock(conf
->hash_locks
);
115 for (i
= 1; i
< NR_STRIPE_HASH_LOCKS
; i
++)
116 spin_lock_nest_lock(conf
->hash_locks
+ i
, conf
->hash_locks
);
117 spin_lock(&conf
->device_lock
);
120 static inline void unlock_all_device_hash_locks_irq(struct r5conf
*conf
)
123 spin_unlock(&conf
->device_lock
);
124 for (i
= NR_STRIPE_HASH_LOCKS
; i
; i
--)
125 spin_unlock(conf
->hash_locks
+ i
- 1);
129 /* bio's attached to a stripe+device for I/O are linked together in bi_sector
130 * order without overlap. There may be several bio's per stripe+device, and
131 * a bio could span several devices.
132 * When walking this list for a particular stripe+device, we must never proceed
133 * beyond a bio that extends past this device, as the next bio might no longer
135 * This function is used to determine the 'next' bio in the list, given the sector
136 * of the current stripe+device
138 static inline struct bio
*r5_next_bio(struct bio
*bio
, sector_t sector
)
140 int sectors
= bio_sectors(bio
);
141 if (bio
->bi_iter
.bi_sector
+ sectors
< sector
+ STRIPE_SECTORS
)
148 * We maintain a biased count of active stripes in the bottom 16 bits of
149 * bi_phys_segments, and a count of processed stripes in the upper 16 bits
151 static inline int raid5_bi_processed_stripes(struct bio
*bio
)
153 atomic_t
*segments
= (atomic_t
*)&bio
->bi_phys_segments
;
154 return (atomic_read(segments
) >> 16) & 0xffff;
157 static inline int raid5_dec_bi_active_stripes(struct bio
*bio
)
159 atomic_t
*segments
= (atomic_t
*)&bio
->bi_phys_segments
;
160 return atomic_sub_return(1, segments
) & 0xffff;
163 static inline void raid5_inc_bi_active_stripes(struct bio
*bio
)
165 atomic_t
*segments
= (atomic_t
*)&bio
->bi_phys_segments
;
166 atomic_inc(segments
);
169 static inline void raid5_set_bi_processed_stripes(struct bio
*bio
,
172 atomic_t
*segments
= (atomic_t
*)&bio
->bi_phys_segments
;
176 old
= atomic_read(segments
);
177 new = (old
& 0xffff) | (cnt
<< 16);
178 } while (atomic_cmpxchg(segments
, old
, new) != old
);
181 static inline void raid5_set_bi_stripes(struct bio
*bio
, unsigned int cnt
)
183 atomic_t
*segments
= (atomic_t
*)&bio
->bi_phys_segments
;
184 atomic_set(segments
, cnt
);
187 /* Find first data disk in a raid6 stripe */
188 static inline int raid6_d0(struct stripe_head
*sh
)
191 /* ddf always start from first device */
193 /* md starts just after Q block */
194 if (sh
->qd_idx
== sh
->disks
- 1)
197 return sh
->qd_idx
+ 1;
199 static inline int raid6_next_disk(int disk
, int raid_disks
)
202 return (disk
< raid_disks
) ? disk
: 0;
205 /* When walking through the disks in a raid5, starting at raid6_d0,
206 * We need to map each disk to a 'slot', where the data disks are slot
207 * 0 .. raid_disks-3, the parity disk is raid_disks-2 and the Q disk
208 * is raid_disks-1. This help does that mapping.
210 static int raid6_idx_to_slot(int idx
, struct stripe_head
*sh
,
211 int *count
, int syndrome_disks
)
217 if (idx
== sh
->pd_idx
)
218 return syndrome_disks
;
219 if (idx
== sh
->qd_idx
)
220 return syndrome_disks
+ 1;
226 static void return_io(struct bio_list
*return_bi
)
229 while ((bi
= bio_list_pop(return_bi
)) != NULL
) {
230 bi
->bi_iter
.bi_size
= 0;
231 trace_block_bio_complete(bdev_get_queue(bi
->bi_bdev
),
237 static void print_raid5_conf (struct r5conf
*conf
);
239 static int stripe_operations_active(struct stripe_head
*sh
)
241 return sh
->check_state
|| sh
->reconstruct_state
||
242 test_bit(STRIPE_BIOFILL_RUN
, &sh
->state
) ||
243 test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
246 static void raid5_wakeup_stripe_thread(struct stripe_head
*sh
)
248 struct r5conf
*conf
= sh
->raid_conf
;
249 struct r5worker_group
*group
;
251 int i
, cpu
= sh
->cpu
;
253 if (!cpu_online(cpu
)) {
254 cpu
= cpumask_any(cpu_online_mask
);
258 if (list_empty(&sh
->lru
)) {
259 struct r5worker_group
*group
;
260 group
= conf
->worker_groups
+ cpu_to_group(cpu
);
261 list_add_tail(&sh
->lru
, &group
->handle_list
);
262 group
->stripes_cnt
++;
266 if (conf
->worker_cnt_per_group
== 0) {
267 md_wakeup_thread(conf
->mddev
->thread
);
271 group
= conf
->worker_groups
+ cpu_to_group(sh
->cpu
);
273 group
->workers
[0].working
= true;
274 /* at least one worker should run to avoid race */
275 queue_work_on(sh
->cpu
, raid5_wq
, &group
->workers
[0].work
);
277 thread_cnt
= group
->stripes_cnt
/ MAX_STRIPE_BATCH
- 1;
278 /* wakeup more workers */
279 for (i
= 1; i
< conf
->worker_cnt_per_group
&& thread_cnt
> 0; i
++) {
280 if (group
->workers
[i
].working
== false) {
281 group
->workers
[i
].working
= true;
282 queue_work_on(sh
->cpu
, raid5_wq
,
283 &group
->workers
[i
].work
);
289 static void do_release_stripe(struct r5conf
*conf
, struct stripe_head
*sh
,
290 struct list_head
*temp_inactive_list
)
292 BUG_ON(!list_empty(&sh
->lru
));
293 BUG_ON(atomic_read(&conf
->active_stripes
)==0);
294 if (test_bit(STRIPE_HANDLE
, &sh
->state
)) {
295 if (test_bit(STRIPE_DELAYED
, &sh
->state
) &&
296 !test_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
297 list_add_tail(&sh
->lru
, &conf
->delayed_list
);
298 else if (test_bit(STRIPE_BIT_DELAY
, &sh
->state
) &&
299 sh
->bm_seq
- conf
->seq_write
> 0)
300 list_add_tail(&sh
->lru
, &conf
->bitmap_list
);
302 clear_bit(STRIPE_DELAYED
, &sh
->state
);
303 clear_bit(STRIPE_BIT_DELAY
, &sh
->state
);
304 if (conf
->worker_cnt_per_group
== 0) {
305 list_add_tail(&sh
->lru
, &conf
->handle_list
);
307 raid5_wakeup_stripe_thread(sh
);
311 md_wakeup_thread(conf
->mddev
->thread
);
313 BUG_ON(stripe_operations_active(sh
));
314 if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
315 if (atomic_dec_return(&conf
->preread_active_stripes
)
317 md_wakeup_thread(conf
->mddev
->thread
);
318 atomic_dec(&conf
->active_stripes
);
319 if (!test_bit(STRIPE_EXPANDING
, &sh
->state
))
320 list_add_tail(&sh
->lru
, temp_inactive_list
);
324 static void __release_stripe(struct r5conf
*conf
, struct stripe_head
*sh
,
325 struct list_head
*temp_inactive_list
)
327 if (atomic_dec_and_test(&sh
->count
))
328 do_release_stripe(conf
, sh
, temp_inactive_list
);
332 * @hash could be NR_STRIPE_HASH_LOCKS, then we have a list of inactive_list
334 * Be careful: Only one task can add/delete stripes from temp_inactive_list at
335 * given time. Adding stripes only takes device lock, while deleting stripes
336 * only takes hash lock.
338 static void release_inactive_stripe_list(struct r5conf
*conf
,
339 struct list_head
*temp_inactive_list
,
343 unsigned long do_wakeup
= 0;
347 if (hash
== NR_STRIPE_HASH_LOCKS
) {
348 size
= NR_STRIPE_HASH_LOCKS
;
349 hash
= NR_STRIPE_HASH_LOCKS
- 1;
353 struct list_head
*list
= &temp_inactive_list
[size
- 1];
356 * We don't hold any lock here yet, raid5_get_active_stripe() might
357 * remove stripes from the list
359 if (!list_empty_careful(list
)) {
360 spin_lock_irqsave(conf
->hash_locks
+ hash
, flags
);
361 if (list_empty(conf
->inactive_list
+ hash
) &&
363 atomic_dec(&conf
->empty_inactive_list_nr
);
364 list_splice_tail_init(list
, conf
->inactive_list
+ hash
);
365 do_wakeup
|= 1 << hash
;
366 spin_unlock_irqrestore(conf
->hash_locks
+ hash
, flags
);
372 for (i
= 0; i
< NR_STRIPE_HASH_LOCKS
; i
++) {
373 if (do_wakeup
& (1 << i
))
374 wake_up(&conf
->wait_for_stripe
[i
]);
378 if (atomic_read(&conf
->active_stripes
) == 0)
379 wake_up(&conf
->wait_for_quiescent
);
380 if (conf
->retry_read_aligned
)
381 md_wakeup_thread(conf
->mddev
->thread
);
385 /* should hold conf->device_lock already */
386 static int release_stripe_list(struct r5conf
*conf
,
387 struct list_head
*temp_inactive_list
)
389 struct stripe_head
*sh
;
391 struct llist_node
*head
;
393 head
= llist_del_all(&conf
->released_stripes
);
394 head
= llist_reverse_order(head
);
398 sh
= llist_entry(head
, struct stripe_head
, release_list
);
399 head
= llist_next(head
);
400 /* sh could be readded after STRIPE_ON_RELEASE_LIST is cleard */
402 clear_bit(STRIPE_ON_RELEASE_LIST
, &sh
->state
);
404 * Don't worry the bit is set here, because if the bit is set
405 * again, the count is always > 1. This is true for
406 * STRIPE_ON_UNPLUG_LIST bit too.
408 hash
= sh
->hash_lock_index
;
409 __release_stripe(conf
, sh
, &temp_inactive_list
[hash
]);
416 void raid5_release_stripe(struct stripe_head
*sh
)
418 struct r5conf
*conf
= sh
->raid_conf
;
420 struct list_head list
;
424 /* Avoid release_list until the last reference.
426 if (atomic_add_unless(&sh
->count
, -1, 1))
429 if (unlikely(!conf
->mddev
->thread
) ||
430 test_and_set_bit(STRIPE_ON_RELEASE_LIST
, &sh
->state
))
432 wakeup
= llist_add(&sh
->release_list
, &conf
->released_stripes
);
434 md_wakeup_thread(conf
->mddev
->thread
);
437 local_irq_save(flags
);
438 /* we are ok here if STRIPE_ON_RELEASE_LIST is set or not */
439 if (atomic_dec_and_lock(&sh
->count
, &conf
->device_lock
)) {
440 INIT_LIST_HEAD(&list
);
441 hash
= sh
->hash_lock_index
;
442 do_release_stripe(conf
, sh
, &list
);
443 spin_unlock(&conf
->device_lock
);
444 release_inactive_stripe_list(conf
, &list
, hash
);
446 local_irq_restore(flags
);
449 static inline void remove_hash(struct stripe_head
*sh
)
451 pr_debug("remove_hash(), stripe %llu\n",
452 (unsigned long long)sh
->sector
);
454 hlist_del_init(&sh
->hash
);
457 static inline void insert_hash(struct r5conf
*conf
, struct stripe_head
*sh
)
459 struct hlist_head
*hp
= stripe_hash(conf
, sh
->sector
);
461 pr_debug("insert_hash(), stripe %llu\n",
462 (unsigned long long)sh
->sector
);
464 hlist_add_head(&sh
->hash
, hp
);
467 /* find an idle stripe, make sure it is unhashed, and return it. */
468 static struct stripe_head
*get_free_stripe(struct r5conf
*conf
, int hash
)
470 struct stripe_head
*sh
= NULL
;
471 struct list_head
*first
;
473 if (list_empty(conf
->inactive_list
+ hash
))
475 first
= (conf
->inactive_list
+ hash
)->next
;
476 sh
= list_entry(first
, struct stripe_head
, lru
);
477 list_del_init(first
);
479 atomic_inc(&conf
->active_stripes
);
480 BUG_ON(hash
!= sh
->hash_lock_index
);
481 if (list_empty(conf
->inactive_list
+ hash
))
482 atomic_inc(&conf
->empty_inactive_list_nr
);
487 static void shrink_buffers(struct stripe_head
*sh
)
491 int num
= sh
->raid_conf
->pool_size
;
493 for (i
= 0; i
< num
; i
++) {
494 WARN_ON(sh
->dev
[i
].page
!= sh
->dev
[i
].orig_page
);
498 sh
->dev
[i
].page
= NULL
;
503 static int grow_buffers(struct stripe_head
*sh
, gfp_t gfp
)
506 int num
= sh
->raid_conf
->pool_size
;
508 for (i
= 0; i
< num
; i
++) {
511 if (!(page
= alloc_page(gfp
))) {
514 sh
->dev
[i
].page
= page
;
515 sh
->dev
[i
].orig_page
= page
;
520 static void raid5_build_block(struct stripe_head
*sh
, int i
, int previous
);
521 static void stripe_set_idx(sector_t stripe
, struct r5conf
*conf
, int previous
,
522 struct stripe_head
*sh
);
524 static void init_stripe(struct stripe_head
*sh
, sector_t sector
, int previous
)
526 struct r5conf
*conf
= sh
->raid_conf
;
529 BUG_ON(atomic_read(&sh
->count
) != 0);
530 BUG_ON(test_bit(STRIPE_HANDLE
, &sh
->state
));
531 BUG_ON(stripe_operations_active(sh
));
532 BUG_ON(sh
->batch_head
);
534 pr_debug("init_stripe called, stripe %llu\n",
535 (unsigned long long)sector
);
537 seq
= read_seqcount_begin(&conf
->gen_lock
);
538 sh
->generation
= conf
->generation
- previous
;
539 sh
->disks
= previous
? conf
->previous_raid_disks
: conf
->raid_disks
;
541 stripe_set_idx(sector
, conf
, previous
, sh
);
544 for (i
= sh
->disks
; i
--; ) {
545 struct r5dev
*dev
= &sh
->dev
[i
];
547 if (dev
->toread
|| dev
->read
|| dev
->towrite
|| dev
->written
||
548 test_bit(R5_LOCKED
, &dev
->flags
)) {
549 printk(KERN_ERR
"sector=%llx i=%d %p %p %p %p %d\n",
550 (unsigned long long)sh
->sector
, i
, dev
->toread
,
551 dev
->read
, dev
->towrite
, dev
->written
,
552 test_bit(R5_LOCKED
, &dev
->flags
));
556 raid5_build_block(sh
, i
, previous
);
558 if (read_seqcount_retry(&conf
->gen_lock
, seq
))
560 sh
->overwrite_disks
= 0;
561 insert_hash(conf
, sh
);
562 sh
->cpu
= smp_processor_id();
563 set_bit(STRIPE_BATCH_READY
, &sh
->state
);
566 static struct stripe_head
*__find_stripe(struct r5conf
*conf
, sector_t sector
,
569 struct stripe_head
*sh
;
571 pr_debug("__find_stripe, sector %llu\n", (unsigned long long)sector
);
572 hlist_for_each_entry(sh
, stripe_hash(conf
, sector
), hash
)
573 if (sh
->sector
== sector
&& sh
->generation
== generation
)
575 pr_debug("__stripe %llu not in cache\n", (unsigned long long)sector
);
580 * Need to check if array has failed when deciding whether to:
582 * - remove non-faulty devices
585 * This determination is simple when no reshape is happening.
586 * However if there is a reshape, we need to carefully check
587 * both the before and after sections.
588 * This is because some failed devices may only affect one
589 * of the two sections, and some non-in_sync devices may
590 * be insync in the section most affected by failed devices.
592 static int calc_degraded(struct r5conf
*conf
)
594 int degraded
, degraded2
;
599 for (i
= 0; i
< conf
->previous_raid_disks
; i
++) {
600 struct md_rdev
*rdev
= rcu_dereference(conf
->disks
[i
].rdev
);
601 if (rdev
&& test_bit(Faulty
, &rdev
->flags
))
602 rdev
= rcu_dereference(conf
->disks
[i
].replacement
);
603 if (!rdev
|| test_bit(Faulty
, &rdev
->flags
))
605 else if (test_bit(In_sync
, &rdev
->flags
))
608 /* not in-sync or faulty.
609 * If the reshape increases the number of devices,
610 * this is being recovered by the reshape, so
611 * this 'previous' section is not in_sync.
612 * If the number of devices is being reduced however,
613 * the device can only be part of the array if
614 * we are reverting a reshape, so this section will
617 if (conf
->raid_disks
>= conf
->previous_raid_disks
)
621 if (conf
->raid_disks
== conf
->previous_raid_disks
)
625 for (i
= 0; i
< conf
->raid_disks
; i
++) {
626 struct md_rdev
*rdev
= rcu_dereference(conf
->disks
[i
].rdev
);
627 if (rdev
&& test_bit(Faulty
, &rdev
->flags
))
628 rdev
= rcu_dereference(conf
->disks
[i
].replacement
);
629 if (!rdev
|| test_bit(Faulty
, &rdev
->flags
))
631 else if (test_bit(In_sync
, &rdev
->flags
))
634 /* not in-sync or faulty.
635 * If reshape increases the number of devices, this
636 * section has already been recovered, else it
637 * almost certainly hasn't.
639 if (conf
->raid_disks
<= conf
->previous_raid_disks
)
643 if (degraded2
> degraded
)
648 static int has_failed(struct r5conf
*conf
)
652 if (conf
->mddev
->reshape_position
== MaxSector
)
653 return conf
->mddev
->degraded
> conf
->max_degraded
;
655 degraded
= calc_degraded(conf
);
656 if (degraded
> conf
->max_degraded
)
662 raid5_get_active_stripe(struct r5conf
*conf
, sector_t sector
,
663 int previous
, int noblock
, int noquiesce
)
665 struct stripe_head
*sh
;
666 int hash
= stripe_hash_locks_hash(sector
);
668 pr_debug("get_stripe, sector %llu\n", (unsigned long long)sector
);
670 spin_lock_irq(conf
->hash_locks
+ hash
);
673 wait_event_lock_irq(conf
->wait_for_quiescent
,
674 conf
->quiesce
== 0 || noquiesce
,
675 *(conf
->hash_locks
+ hash
));
676 sh
= __find_stripe(conf
, sector
, conf
->generation
- previous
);
678 if (!test_bit(R5_INACTIVE_BLOCKED
, &conf
->cache_state
)) {
679 sh
= get_free_stripe(conf
, hash
);
680 if (!sh
&& !test_bit(R5_DID_ALLOC
,
682 set_bit(R5_ALLOC_MORE
,
685 if (noblock
&& sh
== NULL
)
688 set_bit(R5_INACTIVE_BLOCKED
,
690 wait_event_exclusive_cmd(
691 conf
->wait_for_stripe
[hash
],
692 !list_empty(conf
->inactive_list
+ hash
) &&
693 (atomic_read(&conf
->active_stripes
)
694 < (conf
->max_nr_stripes
* 3 / 4)
695 || !test_bit(R5_INACTIVE_BLOCKED
,
696 &conf
->cache_state
)),
697 spin_unlock_irq(conf
->hash_locks
+ hash
),
698 spin_lock_irq(conf
->hash_locks
+ hash
));
699 clear_bit(R5_INACTIVE_BLOCKED
,
702 init_stripe(sh
, sector
, previous
);
703 atomic_inc(&sh
->count
);
705 } else if (!atomic_inc_not_zero(&sh
->count
)) {
706 spin_lock(&conf
->device_lock
);
707 if (!atomic_read(&sh
->count
)) {
708 if (!test_bit(STRIPE_HANDLE
, &sh
->state
))
709 atomic_inc(&conf
->active_stripes
);
710 BUG_ON(list_empty(&sh
->lru
) &&
711 !test_bit(STRIPE_EXPANDING
, &sh
->state
));
712 list_del_init(&sh
->lru
);
714 sh
->group
->stripes_cnt
--;
718 atomic_inc(&sh
->count
);
719 spin_unlock(&conf
->device_lock
);
721 } while (sh
== NULL
);
723 if (!list_empty(conf
->inactive_list
+ hash
))
724 wake_up(&conf
->wait_for_stripe
[hash
]);
726 spin_unlock_irq(conf
->hash_locks
+ hash
);
730 static bool is_full_stripe_write(struct stripe_head
*sh
)
732 BUG_ON(sh
->overwrite_disks
> (sh
->disks
- sh
->raid_conf
->max_degraded
));
733 return sh
->overwrite_disks
== (sh
->disks
- sh
->raid_conf
->max_degraded
);
736 static void lock_two_stripes(struct stripe_head
*sh1
, struct stripe_head
*sh2
)
740 spin_lock(&sh2
->stripe_lock
);
741 spin_lock_nested(&sh1
->stripe_lock
, 1);
743 spin_lock(&sh1
->stripe_lock
);
744 spin_lock_nested(&sh2
->stripe_lock
, 1);
748 static void unlock_two_stripes(struct stripe_head
*sh1
, struct stripe_head
*sh2
)
750 spin_unlock(&sh1
->stripe_lock
);
751 spin_unlock(&sh2
->stripe_lock
);
755 /* Only freshly new full stripe normal write stripe can be added to a batch list */
756 static bool stripe_can_batch(struct stripe_head
*sh
)
758 struct r5conf
*conf
= sh
->raid_conf
;
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 raid5_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
);
892 raid5_end_write_request(struct bio
*bi
);
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 if (r5l_write_stripe(conf
->log
, sh
) == 0)
904 for (i
= disks
; i
--; ) {
906 int replace_only
= 0;
907 struct bio
*bi
, *rbi
;
908 struct md_rdev
*rdev
, *rrdev
= NULL
;
911 if (test_and_clear_bit(R5_Wantwrite
, &sh
->dev
[i
].flags
)) {
912 if (test_and_clear_bit(R5_WantFUA
, &sh
->dev
[i
].flags
))
916 if (test_bit(R5_Discard
, &sh
->dev
[i
].flags
))
918 } else if (test_and_clear_bit(R5_Wantread
, &sh
->dev
[i
].flags
))
920 else if (test_and_clear_bit(R5_WantReplace
,
921 &sh
->dev
[i
].flags
)) {
926 if (test_and_clear_bit(R5_SyncIO
, &sh
->dev
[i
].flags
))
930 bi
= &sh
->dev
[i
].req
;
931 rbi
= &sh
->dev
[i
].rreq
; /* For writing to replacement */
934 rrdev
= rcu_dereference(conf
->disks
[i
].replacement
);
935 smp_mb(); /* Ensure that if rrdev is NULL, rdev won't be */
936 rdev
= rcu_dereference(conf
->disks
[i
].rdev
);
945 /* We raced and saw duplicates */
948 if (test_bit(R5_ReadRepl
, &head_sh
->dev
[i
].flags
) && rrdev
)
953 if (rdev
&& test_bit(Faulty
, &rdev
->flags
))
956 atomic_inc(&rdev
->nr_pending
);
957 if (rrdev
&& test_bit(Faulty
, &rrdev
->flags
))
960 atomic_inc(&rrdev
->nr_pending
);
963 /* We have already checked bad blocks for reads. Now
964 * need to check for writes. We never accept write errors
965 * on the replacement, so we don't to check rrdev.
967 while ((rw
& WRITE
) && rdev
&&
968 test_bit(WriteErrorSeen
, &rdev
->flags
)) {
971 int bad
= is_badblock(rdev
, sh
->sector
, STRIPE_SECTORS
,
972 &first_bad
, &bad_sectors
);
977 set_bit(BlockedBadBlocks
, &rdev
->flags
);
978 if (!conf
->mddev
->external
&&
979 conf
->mddev
->flags
) {
980 /* It is very unlikely, but we might
981 * still need to write out the
982 * bad block log - better give it
984 md_check_recovery(conf
->mddev
);
987 * Because md_wait_for_blocked_rdev
988 * will dec nr_pending, we must
989 * increment it first.
991 atomic_inc(&rdev
->nr_pending
);
992 md_wait_for_blocked_rdev(rdev
, conf
->mddev
);
994 /* Acknowledged bad block - skip the write */
995 rdev_dec_pending(rdev
, conf
->mddev
);
1001 if (s
->syncing
|| s
->expanding
|| s
->expanded
1003 md_sync_acct(rdev
->bdev
, STRIPE_SECTORS
);
1005 set_bit(STRIPE_IO_STARTED
, &sh
->state
);
1008 bi
->bi_bdev
= rdev
->bdev
;
1010 bi
->bi_end_io
= (rw
& WRITE
)
1011 ? raid5_end_write_request
1012 : raid5_end_read_request
;
1013 bi
->bi_private
= sh
;
1015 pr_debug("%s: for %llu schedule op %ld on disc %d\n",
1016 __func__
, (unsigned long long)sh
->sector
,
1018 atomic_inc(&sh
->count
);
1020 atomic_inc(&head_sh
->count
);
1021 if (use_new_offset(conf
, sh
))
1022 bi
->bi_iter
.bi_sector
= (sh
->sector
1023 + rdev
->new_data_offset
);
1025 bi
->bi_iter
.bi_sector
= (sh
->sector
1026 + rdev
->data_offset
);
1027 if (test_bit(R5_ReadNoMerge
, &head_sh
->dev
[i
].flags
))
1028 bi
->bi_rw
|= REQ_NOMERGE
;
1030 if (test_bit(R5_SkipCopy
, &sh
->dev
[i
].flags
))
1031 WARN_ON(test_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
));
1032 sh
->dev
[i
].vec
.bv_page
= sh
->dev
[i
].page
;
1034 bi
->bi_io_vec
[0].bv_len
= STRIPE_SIZE
;
1035 bi
->bi_io_vec
[0].bv_offset
= 0;
1036 bi
->bi_iter
.bi_size
= STRIPE_SIZE
;
1038 * If this is discard request, set bi_vcnt 0. We don't
1039 * want to confuse SCSI because SCSI will replace payload
1041 if (rw
& REQ_DISCARD
)
1044 set_bit(R5_DOUBLE_LOCKED
, &sh
->dev
[i
].flags
);
1046 if (conf
->mddev
->gendisk
)
1047 trace_block_bio_remap(bdev_get_queue(bi
->bi_bdev
),
1048 bi
, disk_devt(conf
->mddev
->gendisk
),
1050 generic_make_request(bi
);
1053 if (s
->syncing
|| s
->expanding
|| s
->expanded
1055 md_sync_acct(rrdev
->bdev
, STRIPE_SECTORS
);
1057 set_bit(STRIPE_IO_STARTED
, &sh
->state
);
1060 rbi
->bi_bdev
= rrdev
->bdev
;
1062 BUG_ON(!(rw
& WRITE
));
1063 rbi
->bi_end_io
= raid5_end_write_request
;
1064 rbi
->bi_private
= sh
;
1066 pr_debug("%s: for %llu schedule op %ld on "
1067 "replacement disc %d\n",
1068 __func__
, (unsigned long long)sh
->sector
,
1070 atomic_inc(&sh
->count
);
1072 atomic_inc(&head_sh
->count
);
1073 if (use_new_offset(conf
, sh
))
1074 rbi
->bi_iter
.bi_sector
= (sh
->sector
1075 + rrdev
->new_data_offset
);
1077 rbi
->bi_iter
.bi_sector
= (sh
->sector
1078 + rrdev
->data_offset
);
1079 if (test_bit(R5_SkipCopy
, &sh
->dev
[i
].flags
))
1080 WARN_ON(test_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
));
1081 sh
->dev
[i
].rvec
.bv_page
= sh
->dev
[i
].page
;
1083 rbi
->bi_io_vec
[0].bv_len
= STRIPE_SIZE
;
1084 rbi
->bi_io_vec
[0].bv_offset
= 0;
1085 rbi
->bi_iter
.bi_size
= STRIPE_SIZE
;
1087 * If this is discard request, set bi_vcnt 0. We don't
1088 * want to confuse SCSI because SCSI will replace payload
1090 if (rw
& REQ_DISCARD
)
1092 if (conf
->mddev
->gendisk
)
1093 trace_block_bio_remap(bdev_get_queue(rbi
->bi_bdev
),
1094 rbi
, disk_devt(conf
->mddev
->gendisk
),
1096 generic_make_request(rbi
);
1098 if (!rdev
&& !rrdev
) {
1100 set_bit(STRIPE_DEGRADED
, &sh
->state
);
1101 pr_debug("skip op %ld on disc %d for sector %llu\n",
1102 bi
->bi_rw
, i
, (unsigned long long)sh
->sector
);
1103 clear_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
1104 set_bit(STRIPE_HANDLE
, &sh
->state
);
1107 if (!head_sh
->batch_head
)
1109 sh
= list_first_entry(&sh
->batch_list
, struct stripe_head
,
1116 static struct dma_async_tx_descriptor
*
1117 async_copy_data(int frombio
, struct bio
*bio
, struct page
**page
,
1118 sector_t sector
, struct dma_async_tx_descriptor
*tx
,
1119 struct stripe_head
*sh
)
1122 struct bvec_iter iter
;
1123 struct page
*bio_page
;
1125 struct async_submit_ctl submit
;
1126 enum async_tx_flags flags
= 0;
1128 if (bio
->bi_iter
.bi_sector
>= sector
)
1129 page_offset
= (signed)(bio
->bi_iter
.bi_sector
- sector
) * 512;
1131 page_offset
= (signed)(sector
- bio
->bi_iter
.bi_sector
) * -512;
1134 flags
|= ASYNC_TX_FENCE
;
1135 init_async_submit(&submit
, flags
, tx
, NULL
, NULL
, NULL
);
1137 bio_for_each_segment(bvl
, bio
, iter
) {
1138 int len
= bvl
.bv_len
;
1142 if (page_offset
< 0) {
1143 b_offset
= -page_offset
;
1144 page_offset
+= b_offset
;
1148 if (len
> 0 && page_offset
+ len
> STRIPE_SIZE
)
1149 clen
= STRIPE_SIZE
- page_offset
;
1154 b_offset
+= bvl
.bv_offset
;
1155 bio_page
= bvl
.bv_page
;
1157 if (sh
->raid_conf
->skip_copy
&&
1158 b_offset
== 0 && page_offset
== 0 &&
1159 clen
== STRIPE_SIZE
)
1162 tx
= async_memcpy(*page
, bio_page
, page_offset
,
1163 b_offset
, clen
, &submit
);
1165 tx
= async_memcpy(bio_page
, *page
, b_offset
,
1166 page_offset
, clen
, &submit
);
1168 /* chain the operations */
1169 submit
.depend_tx
= tx
;
1171 if (clen
< len
) /* hit end of page */
1179 static void ops_complete_biofill(void *stripe_head_ref
)
1181 struct stripe_head
*sh
= stripe_head_ref
;
1182 struct bio_list return_bi
= BIO_EMPTY_LIST
;
1185 pr_debug("%s: stripe %llu\n", __func__
,
1186 (unsigned long long)sh
->sector
);
1188 /* clear completed biofills */
1189 for (i
= sh
->disks
; i
--; ) {
1190 struct r5dev
*dev
= &sh
->dev
[i
];
1192 /* acknowledge completion of a biofill operation */
1193 /* and check if we need to reply to a read request,
1194 * new R5_Wantfill requests are held off until
1195 * !STRIPE_BIOFILL_RUN
1197 if (test_and_clear_bit(R5_Wantfill
, &dev
->flags
)) {
1198 struct bio
*rbi
, *rbi2
;
1203 while (rbi
&& rbi
->bi_iter
.bi_sector
<
1204 dev
->sector
+ STRIPE_SECTORS
) {
1205 rbi2
= r5_next_bio(rbi
, dev
->sector
);
1206 if (!raid5_dec_bi_active_stripes(rbi
))
1207 bio_list_add(&return_bi
, rbi
);
1212 clear_bit(STRIPE_BIOFILL_RUN
, &sh
->state
);
1214 return_io(&return_bi
);
1216 set_bit(STRIPE_HANDLE
, &sh
->state
);
1217 raid5_release_stripe(sh
);
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
);
1280 raid5_release_stripe(sh
);
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
);
1706 raid5_release_stripe(sh
);
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
);
1864 raid5_release_stripe(sh
);
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
);
2026 raid5_release_stripe(sh
);
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 raid5_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 kmem_cache_destroy(conf
->slab_cache
);
2281 conf
->slab_cache
= NULL
;
2284 static void raid5_end_read_request(struct bio
* bi
)
2286 struct stripe_head
*sh
= bi
->bi_private
;
2287 struct r5conf
*conf
= sh
->raid_conf
;
2288 int disks
= sh
->disks
, i
;
2289 char b
[BDEVNAME_SIZE
];
2290 struct md_rdev
*rdev
= NULL
;
2293 for (i
=0 ; i
<disks
; i
++)
2294 if (bi
== &sh
->dev
[i
].req
)
2297 pr_debug("end_read_request %llu/%d, count: %d, error %d.\n",
2298 (unsigned long long)sh
->sector
, i
, atomic_read(&sh
->count
),
2304 if (test_bit(R5_ReadRepl
, &sh
->dev
[i
].flags
))
2305 /* If replacement finished while this request was outstanding,
2306 * 'replacement' might be NULL already.
2307 * In that case it moved down to 'rdev'.
2308 * rdev is not removed until all requests are finished.
2310 rdev
= conf
->disks
[i
].replacement
;
2312 rdev
= conf
->disks
[i
].rdev
;
2314 if (use_new_offset(conf
, sh
))
2315 s
= sh
->sector
+ rdev
->new_data_offset
;
2317 s
= sh
->sector
+ rdev
->data_offset
;
2318 if (!bi
->bi_error
) {
2319 set_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
);
2320 if (test_bit(R5_ReadError
, &sh
->dev
[i
].flags
)) {
2321 /* Note that this cannot happen on a
2322 * replacement device. We just fail those on
2327 "md/raid:%s: read error corrected"
2328 " (%lu sectors at %llu on %s)\n",
2329 mdname(conf
->mddev
), STRIPE_SECTORS
,
2330 (unsigned long long)s
,
2331 bdevname(rdev
->bdev
, b
));
2332 atomic_add(STRIPE_SECTORS
, &rdev
->corrected_errors
);
2333 clear_bit(R5_ReadError
, &sh
->dev
[i
].flags
);
2334 clear_bit(R5_ReWrite
, &sh
->dev
[i
].flags
);
2335 } else if (test_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
))
2336 clear_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
);
2338 if (atomic_read(&rdev
->read_errors
))
2339 atomic_set(&rdev
->read_errors
, 0);
2341 const char *bdn
= bdevname(rdev
->bdev
, b
);
2345 clear_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
);
2346 atomic_inc(&rdev
->read_errors
);
2347 if (test_bit(R5_ReadRepl
, &sh
->dev
[i
].flags
))
2350 "md/raid:%s: read error on replacement device "
2351 "(sector %llu on %s).\n",
2352 mdname(conf
->mddev
),
2353 (unsigned long long)s
,
2355 else if (conf
->mddev
->degraded
>= conf
->max_degraded
) {
2359 "md/raid:%s: read error not correctable "
2360 "(sector %llu on %s).\n",
2361 mdname(conf
->mddev
),
2362 (unsigned long long)s
,
2364 } else if (test_bit(R5_ReWrite
, &sh
->dev
[i
].flags
)) {
2369 "md/raid:%s: read error NOT corrected!! "
2370 "(sector %llu on %s).\n",
2371 mdname(conf
->mddev
),
2372 (unsigned long long)s
,
2374 } else if (atomic_read(&rdev
->read_errors
)
2375 > conf
->max_nr_stripes
)
2377 "md/raid:%s: Too many read errors, failing device %s.\n",
2378 mdname(conf
->mddev
), bdn
);
2381 if (set_bad
&& test_bit(In_sync
, &rdev
->flags
)
2382 && !test_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
))
2385 if (test_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
)) {
2386 set_bit(R5_ReadError
, &sh
->dev
[i
].flags
);
2387 clear_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
);
2389 set_bit(R5_ReadNoMerge
, &sh
->dev
[i
].flags
);
2391 clear_bit(R5_ReadError
, &sh
->dev
[i
].flags
);
2392 clear_bit(R5_ReWrite
, &sh
->dev
[i
].flags
);
2394 && test_bit(In_sync
, &rdev
->flags
)
2395 && rdev_set_badblocks(
2396 rdev
, sh
->sector
, STRIPE_SECTORS
, 0)))
2397 md_error(conf
->mddev
, rdev
);
2400 rdev_dec_pending(rdev
, conf
->mddev
);
2401 clear_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
2402 set_bit(STRIPE_HANDLE
, &sh
->state
);
2403 raid5_release_stripe(sh
);
2406 static void raid5_end_write_request(struct bio
*bi
)
2408 struct stripe_head
*sh
= bi
->bi_private
;
2409 struct r5conf
*conf
= sh
->raid_conf
;
2410 int disks
= sh
->disks
, i
;
2411 struct md_rdev
*uninitialized_var(rdev
);
2414 int replacement
= 0;
2416 for (i
= 0 ; i
< disks
; i
++) {
2417 if (bi
== &sh
->dev
[i
].req
) {
2418 rdev
= conf
->disks
[i
].rdev
;
2421 if (bi
== &sh
->dev
[i
].rreq
) {
2422 rdev
= conf
->disks
[i
].replacement
;
2426 /* rdev was removed and 'replacement'
2427 * replaced it. rdev is not removed
2428 * until all requests are finished.
2430 rdev
= conf
->disks
[i
].rdev
;
2434 pr_debug("end_write_request %llu/%d, count %d, error: %d.\n",
2435 (unsigned long long)sh
->sector
, i
, atomic_read(&sh
->count
),
2444 md_error(conf
->mddev
, rdev
);
2445 else if (is_badblock(rdev
, sh
->sector
,
2447 &first_bad
, &bad_sectors
))
2448 set_bit(R5_MadeGoodRepl
, &sh
->dev
[i
].flags
);
2451 set_bit(STRIPE_DEGRADED
, &sh
->state
);
2452 set_bit(WriteErrorSeen
, &rdev
->flags
);
2453 set_bit(R5_WriteError
, &sh
->dev
[i
].flags
);
2454 if (!test_and_set_bit(WantReplacement
, &rdev
->flags
))
2455 set_bit(MD_RECOVERY_NEEDED
,
2456 &rdev
->mddev
->recovery
);
2457 } else if (is_badblock(rdev
, sh
->sector
,
2459 &first_bad
, &bad_sectors
)) {
2460 set_bit(R5_MadeGood
, &sh
->dev
[i
].flags
);
2461 if (test_bit(R5_ReadError
, &sh
->dev
[i
].flags
))
2462 /* That was a successful write so make
2463 * sure it looks like we already did
2466 set_bit(R5_ReWrite
, &sh
->dev
[i
].flags
);
2469 rdev_dec_pending(rdev
, conf
->mddev
);
2471 if (sh
->batch_head
&& bi
->bi_error
&& !replacement
)
2472 set_bit(STRIPE_BATCH_ERR
, &sh
->batch_head
->state
);
2474 if (!test_and_clear_bit(R5_DOUBLE_LOCKED
, &sh
->dev
[i
].flags
))
2475 clear_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
2476 set_bit(STRIPE_HANDLE
, &sh
->state
);
2477 raid5_release_stripe(sh
);
2479 if (sh
->batch_head
&& sh
!= sh
->batch_head
)
2480 raid5_release_stripe(sh
->batch_head
);
2483 static void raid5_build_block(struct stripe_head
*sh
, int i
, int previous
)
2485 struct r5dev
*dev
= &sh
->dev
[i
];
2487 bio_init(&dev
->req
);
2488 dev
->req
.bi_io_vec
= &dev
->vec
;
2489 dev
->req
.bi_max_vecs
= 1;
2490 dev
->req
.bi_private
= sh
;
2492 bio_init(&dev
->rreq
);
2493 dev
->rreq
.bi_io_vec
= &dev
->rvec
;
2494 dev
->rreq
.bi_max_vecs
= 1;
2495 dev
->rreq
.bi_private
= sh
;
2498 dev
->sector
= raid5_compute_blocknr(sh
, i
, previous
);
2501 static void error(struct mddev
*mddev
, struct md_rdev
*rdev
)
2503 char b
[BDEVNAME_SIZE
];
2504 struct r5conf
*conf
= mddev
->private;
2505 unsigned long flags
;
2506 pr_debug("raid456: error called\n");
2508 spin_lock_irqsave(&conf
->device_lock
, flags
);
2509 clear_bit(In_sync
, &rdev
->flags
);
2510 mddev
->degraded
= calc_degraded(conf
);
2511 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
2512 set_bit(MD_RECOVERY_INTR
, &mddev
->recovery
);
2514 set_bit(Blocked
, &rdev
->flags
);
2515 set_bit(Faulty
, &rdev
->flags
);
2516 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
2517 set_bit(MD_CHANGE_PENDING
, &mddev
->flags
);
2519 "md/raid:%s: Disk failure on %s, disabling device.\n"
2520 "md/raid:%s: Operation continuing on %d devices.\n",
2522 bdevname(rdev
->bdev
, b
),
2524 conf
->raid_disks
- mddev
->degraded
);
2528 * Input: a 'big' sector number,
2529 * Output: index of the data and parity disk, and the sector # in them.
2531 sector_t
raid5_compute_sector(struct r5conf
*conf
, sector_t r_sector
,
2532 int previous
, int *dd_idx
,
2533 struct stripe_head
*sh
)
2535 sector_t stripe
, stripe2
;
2536 sector_t chunk_number
;
2537 unsigned int chunk_offset
;
2540 sector_t new_sector
;
2541 int algorithm
= previous
? conf
->prev_algo
2543 int sectors_per_chunk
= previous
? conf
->prev_chunk_sectors
2544 : conf
->chunk_sectors
;
2545 int raid_disks
= previous
? conf
->previous_raid_disks
2547 int data_disks
= raid_disks
- conf
->max_degraded
;
2549 /* First compute the information on this sector */
2552 * Compute the chunk number and the sector offset inside the chunk
2554 chunk_offset
= sector_div(r_sector
, sectors_per_chunk
);
2555 chunk_number
= r_sector
;
2558 * Compute the stripe number
2560 stripe
= chunk_number
;
2561 *dd_idx
= sector_div(stripe
, data_disks
);
2564 * Select the parity disk based on the user selected algorithm.
2566 pd_idx
= qd_idx
= -1;
2567 switch(conf
->level
) {
2569 pd_idx
= data_disks
;
2572 switch (algorithm
) {
2573 case ALGORITHM_LEFT_ASYMMETRIC
:
2574 pd_idx
= data_disks
- sector_div(stripe2
, raid_disks
);
2575 if (*dd_idx
>= pd_idx
)
2578 case ALGORITHM_RIGHT_ASYMMETRIC
:
2579 pd_idx
= sector_div(stripe2
, raid_disks
);
2580 if (*dd_idx
>= pd_idx
)
2583 case ALGORITHM_LEFT_SYMMETRIC
:
2584 pd_idx
= data_disks
- sector_div(stripe2
, raid_disks
);
2585 *dd_idx
= (pd_idx
+ 1 + *dd_idx
) % raid_disks
;
2587 case ALGORITHM_RIGHT_SYMMETRIC
:
2588 pd_idx
= sector_div(stripe2
, raid_disks
);
2589 *dd_idx
= (pd_idx
+ 1 + *dd_idx
) % raid_disks
;
2591 case ALGORITHM_PARITY_0
:
2595 case ALGORITHM_PARITY_N
:
2596 pd_idx
= data_disks
;
2604 switch (algorithm
) {
2605 case ALGORITHM_LEFT_ASYMMETRIC
:
2606 pd_idx
= raid_disks
- 1 - sector_div(stripe2
, raid_disks
);
2607 qd_idx
= pd_idx
+ 1;
2608 if (pd_idx
== raid_disks
-1) {
2609 (*dd_idx
)++; /* Q D D D P */
2611 } else if (*dd_idx
>= pd_idx
)
2612 (*dd_idx
) += 2; /* D D P Q D */
2614 case ALGORITHM_RIGHT_ASYMMETRIC
:
2615 pd_idx
= sector_div(stripe2
, raid_disks
);
2616 qd_idx
= pd_idx
+ 1;
2617 if (pd_idx
== raid_disks
-1) {
2618 (*dd_idx
)++; /* Q D D D P */
2620 } else if (*dd_idx
>= pd_idx
)
2621 (*dd_idx
) += 2; /* D D P Q D */
2623 case ALGORITHM_LEFT_SYMMETRIC
:
2624 pd_idx
= raid_disks
- 1 - sector_div(stripe2
, raid_disks
);
2625 qd_idx
= (pd_idx
+ 1) % raid_disks
;
2626 *dd_idx
= (pd_idx
+ 2 + *dd_idx
) % raid_disks
;
2628 case ALGORITHM_RIGHT_SYMMETRIC
:
2629 pd_idx
= sector_div(stripe2
, raid_disks
);
2630 qd_idx
= (pd_idx
+ 1) % raid_disks
;
2631 *dd_idx
= (pd_idx
+ 2 + *dd_idx
) % raid_disks
;
2634 case ALGORITHM_PARITY_0
:
2639 case ALGORITHM_PARITY_N
:
2640 pd_idx
= data_disks
;
2641 qd_idx
= data_disks
+ 1;
2644 case ALGORITHM_ROTATING_ZERO_RESTART
:
2645 /* Exactly the same as RIGHT_ASYMMETRIC, but or
2646 * of blocks for computing Q is different.
2648 pd_idx
= sector_div(stripe2
, raid_disks
);
2649 qd_idx
= pd_idx
+ 1;
2650 if (pd_idx
== raid_disks
-1) {
2651 (*dd_idx
)++; /* Q D D D P */
2653 } else if (*dd_idx
>= pd_idx
)
2654 (*dd_idx
) += 2; /* D D P Q D */
2658 case ALGORITHM_ROTATING_N_RESTART
:
2659 /* Same a left_asymmetric, by first stripe is
2660 * D D D P Q rather than
2664 pd_idx
= raid_disks
- 1 - sector_div(stripe2
, raid_disks
);
2665 qd_idx
= pd_idx
+ 1;
2666 if (pd_idx
== raid_disks
-1) {
2667 (*dd_idx
)++; /* Q D D D P */
2669 } else if (*dd_idx
>= pd_idx
)
2670 (*dd_idx
) += 2; /* D D P Q D */
2674 case ALGORITHM_ROTATING_N_CONTINUE
:
2675 /* Same as left_symmetric but Q is before P */
2676 pd_idx
= raid_disks
- 1 - sector_div(stripe2
, raid_disks
);
2677 qd_idx
= (pd_idx
+ raid_disks
- 1) % raid_disks
;
2678 *dd_idx
= (pd_idx
+ 1 + *dd_idx
) % raid_disks
;
2682 case ALGORITHM_LEFT_ASYMMETRIC_6
:
2683 /* RAID5 left_asymmetric, with Q on last device */
2684 pd_idx
= data_disks
- sector_div(stripe2
, raid_disks
-1);
2685 if (*dd_idx
>= pd_idx
)
2687 qd_idx
= raid_disks
- 1;
2690 case ALGORITHM_RIGHT_ASYMMETRIC_6
:
2691 pd_idx
= sector_div(stripe2
, raid_disks
-1);
2692 if (*dd_idx
>= pd_idx
)
2694 qd_idx
= raid_disks
- 1;
2697 case ALGORITHM_LEFT_SYMMETRIC_6
:
2698 pd_idx
= data_disks
- sector_div(stripe2
, raid_disks
-1);
2699 *dd_idx
= (pd_idx
+ 1 + *dd_idx
) % (raid_disks
-1);
2700 qd_idx
= raid_disks
- 1;
2703 case ALGORITHM_RIGHT_SYMMETRIC_6
:
2704 pd_idx
= sector_div(stripe2
, raid_disks
-1);
2705 *dd_idx
= (pd_idx
+ 1 + *dd_idx
) % (raid_disks
-1);
2706 qd_idx
= raid_disks
- 1;
2709 case ALGORITHM_PARITY_0_6
:
2712 qd_idx
= raid_disks
- 1;
2722 sh
->pd_idx
= pd_idx
;
2723 sh
->qd_idx
= qd_idx
;
2724 sh
->ddf_layout
= ddf_layout
;
2727 * Finally, compute the new sector number
2729 new_sector
= (sector_t
)stripe
* sectors_per_chunk
+ chunk_offset
;
2733 sector_t
raid5_compute_blocknr(struct stripe_head
*sh
, int i
, int previous
)
2735 struct r5conf
*conf
= sh
->raid_conf
;
2736 int raid_disks
= sh
->disks
;
2737 int data_disks
= raid_disks
- conf
->max_degraded
;
2738 sector_t new_sector
= sh
->sector
, check
;
2739 int sectors_per_chunk
= previous
? conf
->prev_chunk_sectors
2740 : conf
->chunk_sectors
;
2741 int algorithm
= previous
? conf
->prev_algo
2745 sector_t chunk_number
;
2746 int dummy1
, dd_idx
= i
;
2748 struct stripe_head sh2
;
2750 chunk_offset
= sector_div(new_sector
, sectors_per_chunk
);
2751 stripe
= new_sector
;
2753 if (i
== sh
->pd_idx
)
2755 switch(conf
->level
) {
2758 switch (algorithm
) {
2759 case ALGORITHM_LEFT_ASYMMETRIC
:
2760 case ALGORITHM_RIGHT_ASYMMETRIC
:
2764 case ALGORITHM_LEFT_SYMMETRIC
:
2765 case ALGORITHM_RIGHT_SYMMETRIC
:
2768 i
-= (sh
->pd_idx
+ 1);
2770 case ALGORITHM_PARITY_0
:
2773 case ALGORITHM_PARITY_N
:
2780 if (i
== sh
->qd_idx
)
2781 return 0; /* It is the Q disk */
2782 switch (algorithm
) {
2783 case ALGORITHM_LEFT_ASYMMETRIC
:
2784 case ALGORITHM_RIGHT_ASYMMETRIC
:
2785 case ALGORITHM_ROTATING_ZERO_RESTART
:
2786 case ALGORITHM_ROTATING_N_RESTART
:
2787 if (sh
->pd_idx
== raid_disks
-1)
2788 i
--; /* Q D D D P */
2789 else if (i
> sh
->pd_idx
)
2790 i
-= 2; /* D D P Q D */
2792 case ALGORITHM_LEFT_SYMMETRIC
:
2793 case ALGORITHM_RIGHT_SYMMETRIC
:
2794 if (sh
->pd_idx
== raid_disks
-1)
2795 i
--; /* Q D D D P */
2800 i
-= (sh
->pd_idx
+ 2);
2803 case ALGORITHM_PARITY_0
:
2806 case ALGORITHM_PARITY_N
:
2808 case ALGORITHM_ROTATING_N_CONTINUE
:
2809 /* Like left_symmetric, but P is before Q */
2810 if (sh
->pd_idx
== 0)
2811 i
--; /* P D D D Q */
2816 i
-= (sh
->pd_idx
+ 1);
2819 case ALGORITHM_LEFT_ASYMMETRIC_6
:
2820 case ALGORITHM_RIGHT_ASYMMETRIC_6
:
2824 case ALGORITHM_LEFT_SYMMETRIC_6
:
2825 case ALGORITHM_RIGHT_SYMMETRIC_6
:
2827 i
+= data_disks
+ 1;
2828 i
-= (sh
->pd_idx
+ 1);
2830 case ALGORITHM_PARITY_0_6
:
2839 chunk_number
= stripe
* data_disks
+ i
;
2840 r_sector
= chunk_number
* sectors_per_chunk
+ chunk_offset
;
2842 check
= raid5_compute_sector(conf
, r_sector
,
2843 previous
, &dummy1
, &sh2
);
2844 if (check
!= sh
->sector
|| dummy1
!= dd_idx
|| sh2
.pd_idx
!= sh
->pd_idx
2845 || sh2
.qd_idx
!= sh
->qd_idx
) {
2846 printk(KERN_ERR
"md/raid:%s: compute_blocknr: map not correct\n",
2847 mdname(conf
->mddev
));
2854 schedule_reconstruction(struct stripe_head
*sh
, struct stripe_head_state
*s
,
2855 int rcw
, int expand
)
2857 int i
, pd_idx
= sh
->pd_idx
, qd_idx
= sh
->qd_idx
, disks
= sh
->disks
;
2858 struct r5conf
*conf
= sh
->raid_conf
;
2859 int level
= conf
->level
;
2863 for (i
= disks
; i
--; ) {
2864 struct r5dev
*dev
= &sh
->dev
[i
];
2867 set_bit(R5_LOCKED
, &dev
->flags
);
2868 set_bit(R5_Wantdrain
, &dev
->flags
);
2870 clear_bit(R5_UPTODATE
, &dev
->flags
);
2874 /* if we are not expanding this is a proper write request, and
2875 * there will be bios with new data to be drained into the
2880 /* False alarm, nothing to do */
2882 sh
->reconstruct_state
= reconstruct_state_drain_run
;
2883 set_bit(STRIPE_OP_BIODRAIN
, &s
->ops_request
);
2885 sh
->reconstruct_state
= reconstruct_state_run
;
2887 set_bit(STRIPE_OP_RECONSTRUCT
, &s
->ops_request
);
2889 if (s
->locked
+ conf
->max_degraded
== disks
)
2890 if (!test_and_set_bit(STRIPE_FULL_WRITE
, &sh
->state
))
2891 atomic_inc(&conf
->pending_full_writes
);
2893 BUG_ON(!(test_bit(R5_UPTODATE
, &sh
->dev
[pd_idx
].flags
) ||
2894 test_bit(R5_Wantcompute
, &sh
->dev
[pd_idx
].flags
)));
2895 BUG_ON(level
== 6 &&
2896 (!(test_bit(R5_UPTODATE
, &sh
->dev
[qd_idx
].flags
) ||
2897 test_bit(R5_Wantcompute
, &sh
->dev
[qd_idx
].flags
))));
2899 for (i
= disks
; i
--; ) {
2900 struct r5dev
*dev
= &sh
->dev
[i
];
2901 if (i
== pd_idx
|| i
== qd_idx
)
2905 (test_bit(R5_UPTODATE
, &dev
->flags
) ||
2906 test_bit(R5_Wantcompute
, &dev
->flags
))) {
2907 set_bit(R5_Wantdrain
, &dev
->flags
);
2908 set_bit(R5_LOCKED
, &dev
->flags
);
2909 clear_bit(R5_UPTODATE
, &dev
->flags
);
2914 /* False alarm - nothing to do */
2916 sh
->reconstruct_state
= reconstruct_state_prexor_drain_run
;
2917 set_bit(STRIPE_OP_PREXOR
, &s
->ops_request
);
2918 set_bit(STRIPE_OP_BIODRAIN
, &s
->ops_request
);
2919 set_bit(STRIPE_OP_RECONSTRUCT
, &s
->ops_request
);
2922 /* keep the parity disk(s) locked while asynchronous operations
2925 set_bit(R5_LOCKED
, &sh
->dev
[pd_idx
].flags
);
2926 clear_bit(R5_UPTODATE
, &sh
->dev
[pd_idx
].flags
);
2930 int qd_idx
= sh
->qd_idx
;
2931 struct r5dev
*dev
= &sh
->dev
[qd_idx
];
2933 set_bit(R5_LOCKED
, &dev
->flags
);
2934 clear_bit(R5_UPTODATE
, &dev
->flags
);
2938 pr_debug("%s: stripe %llu locked: %d ops_request: %lx\n",
2939 __func__
, (unsigned long long)sh
->sector
,
2940 s
->locked
, s
->ops_request
);
2944 * Each stripe/dev can have one or more bion attached.
2945 * toread/towrite point to the first in a chain.
2946 * The bi_next chain must be in order.
2948 static int add_stripe_bio(struct stripe_head
*sh
, struct bio
*bi
, int dd_idx
,
2949 int forwrite
, int previous
)
2952 struct r5conf
*conf
= sh
->raid_conf
;
2955 pr_debug("adding bi b#%llu to stripe s#%llu\n",
2956 (unsigned long long)bi
->bi_iter
.bi_sector
,
2957 (unsigned long long)sh
->sector
);
2960 * If several bio share a stripe. The bio bi_phys_segments acts as a
2961 * reference count to avoid race. The reference count should already be
2962 * increased before this function is called (for example, in
2963 * make_request()), so other bio sharing this stripe will not free the
2964 * stripe. If a stripe is owned by one stripe, the stripe lock will
2967 spin_lock_irq(&sh
->stripe_lock
);
2968 /* Don't allow new IO added to stripes in batch list */
2972 bip
= &sh
->dev
[dd_idx
].towrite
;
2976 bip
= &sh
->dev
[dd_idx
].toread
;
2977 while (*bip
&& (*bip
)->bi_iter
.bi_sector
< bi
->bi_iter
.bi_sector
) {
2978 if (bio_end_sector(*bip
) > bi
->bi_iter
.bi_sector
)
2980 bip
= & (*bip
)->bi_next
;
2982 if (*bip
&& (*bip
)->bi_iter
.bi_sector
< bio_end_sector(bi
))
2985 if (!forwrite
|| previous
)
2986 clear_bit(STRIPE_BATCH_READY
, &sh
->state
);
2988 BUG_ON(*bip
&& bi
->bi_next
&& (*bip
) != bi
->bi_next
);
2992 raid5_inc_bi_active_stripes(bi
);
2995 /* check if page is covered */
2996 sector_t sector
= sh
->dev
[dd_idx
].sector
;
2997 for (bi
=sh
->dev
[dd_idx
].towrite
;
2998 sector
< sh
->dev
[dd_idx
].sector
+ STRIPE_SECTORS
&&
2999 bi
&& bi
->bi_iter
.bi_sector
<= sector
;
3000 bi
= r5_next_bio(bi
, sh
->dev
[dd_idx
].sector
)) {
3001 if (bio_end_sector(bi
) >= sector
)
3002 sector
= bio_end_sector(bi
);
3004 if (sector
>= sh
->dev
[dd_idx
].sector
+ STRIPE_SECTORS
)
3005 if (!test_and_set_bit(R5_OVERWRITE
, &sh
->dev
[dd_idx
].flags
))
3006 sh
->overwrite_disks
++;
3009 pr_debug("added bi b#%llu to stripe s#%llu, disk %d.\n",
3010 (unsigned long long)(*bip
)->bi_iter
.bi_sector
,
3011 (unsigned long long)sh
->sector
, dd_idx
);
3013 if (conf
->mddev
->bitmap
&& firstwrite
) {
3014 /* Cannot hold spinlock over bitmap_startwrite,
3015 * but must ensure this isn't added to a batch until
3016 * we have added to the bitmap and set bm_seq.
3017 * So set STRIPE_BITMAP_PENDING to prevent
3019 * If multiple add_stripe_bio() calls race here they
3020 * much all set STRIPE_BITMAP_PENDING. So only the first one
3021 * to complete "bitmap_startwrite" gets to set
3022 * STRIPE_BIT_DELAY. This is important as once a stripe
3023 * is added to a batch, STRIPE_BIT_DELAY cannot be changed
3026 set_bit(STRIPE_BITMAP_PENDING
, &sh
->state
);
3027 spin_unlock_irq(&sh
->stripe_lock
);
3028 bitmap_startwrite(conf
->mddev
->bitmap
, sh
->sector
,
3030 spin_lock_irq(&sh
->stripe_lock
);
3031 clear_bit(STRIPE_BITMAP_PENDING
, &sh
->state
);
3032 if (!sh
->batch_head
) {
3033 sh
->bm_seq
= conf
->seq_flush
+1;
3034 set_bit(STRIPE_BIT_DELAY
, &sh
->state
);
3037 spin_unlock_irq(&sh
->stripe_lock
);
3039 if (stripe_can_batch(sh
))
3040 stripe_add_to_batch_list(conf
, sh
);
3044 set_bit(R5_Overlap
, &sh
->dev
[dd_idx
].flags
);
3045 spin_unlock_irq(&sh
->stripe_lock
);
3049 static void end_reshape(struct r5conf
*conf
);
3051 static void stripe_set_idx(sector_t stripe
, struct r5conf
*conf
, int previous
,
3052 struct stripe_head
*sh
)
3054 int sectors_per_chunk
=
3055 previous
? conf
->prev_chunk_sectors
: conf
->chunk_sectors
;
3057 int chunk_offset
= sector_div(stripe
, sectors_per_chunk
);
3058 int disks
= previous
? conf
->previous_raid_disks
: conf
->raid_disks
;
3060 raid5_compute_sector(conf
,
3061 stripe
* (disks
- conf
->max_degraded
)
3062 *sectors_per_chunk
+ chunk_offset
,
3068 handle_failed_stripe(struct r5conf
*conf
, struct stripe_head
*sh
,
3069 struct stripe_head_state
*s
, int disks
,
3070 struct bio_list
*return_bi
)
3073 BUG_ON(sh
->batch_head
);
3074 for (i
= disks
; i
--; ) {
3078 if (test_bit(R5_ReadError
, &sh
->dev
[i
].flags
)) {
3079 struct md_rdev
*rdev
;
3081 rdev
= rcu_dereference(conf
->disks
[i
].rdev
);
3082 if (rdev
&& test_bit(In_sync
, &rdev
->flags
))
3083 atomic_inc(&rdev
->nr_pending
);
3088 if (!rdev_set_badblocks(
3092 md_error(conf
->mddev
, rdev
);
3093 rdev_dec_pending(rdev
, conf
->mddev
);
3096 spin_lock_irq(&sh
->stripe_lock
);
3097 /* fail all writes first */
3098 bi
= sh
->dev
[i
].towrite
;
3099 sh
->dev
[i
].towrite
= NULL
;
3100 sh
->overwrite_disks
= 0;
3101 spin_unlock_irq(&sh
->stripe_lock
);
3105 r5l_stripe_write_finished(sh
);
3107 if (test_and_clear_bit(R5_Overlap
, &sh
->dev
[i
].flags
))
3108 wake_up(&conf
->wait_for_overlap
);
3110 while (bi
&& bi
->bi_iter
.bi_sector
<
3111 sh
->dev
[i
].sector
+ STRIPE_SECTORS
) {
3112 struct bio
*nextbi
= r5_next_bio(bi
, sh
->dev
[i
].sector
);
3114 bi
->bi_error
= -EIO
;
3115 if (!raid5_dec_bi_active_stripes(bi
)) {
3116 md_write_end(conf
->mddev
);
3117 bio_list_add(return_bi
, bi
);
3122 bitmap_endwrite(conf
->mddev
->bitmap
, sh
->sector
,
3123 STRIPE_SECTORS
, 0, 0);
3125 /* and fail all 'written' */
3126 bi
= sh
->dev
[i
].written
;
3127 sh
->dev
[i
].written
= NULL
;
3128 if (test_and_clear_bit(R5_SkipCopy
, &sh
->dev
[i
].flags
)) {
3129 WARN_ON(test_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
));
3130 sh
->dev
[i
].page
= sh
->dev
[i
].orig_page
;
3133 if (bi
) bitmap_end
= 1;
3134 while (bi
&& bi
->bi_iter
.bi_sector
<
3135 sh
->dev
[i
].sector
+ STRIPE_SECTORS
) {
3136 struct bio
*bi2
= r5_next_bio(bi
, sh
->dev
[i
].sector
);
3138 bi
->bi_error
= -EIO
;
3139 if (!raid5_dec_bi_active_stripes(bi
)) {
3140 md_write_end(conf
->mddev
);
3141 bio_list_add(return_bi
, bi
);
3146 /* fail any reads if this device is non-operational and
3147 * the data has not reached the cache yet.
3149 if (!test_bit(R5_Wantfill
, &sh
->dev
[i
].flags
) &&
3150 (!test_bit(R5_Insync
, &sh
->dev
[i
].flags
) ||
3151 test_bit(R5_ReadError
, &sh
->dev
[i
].flags
))) {
3152 spin_lock_irq(&sh
->stripe_lock
);
3153 bi
= sh
->dev
[i
].toread
;
3154 sh
->dev
[i
].toread
= NULL
;
3155 spin_unlock_irq(&sh
->stripe_lock
);
3156 if (test_and_clear_bit(R5_Overlap
, &sh
->dev
[i
].flags
))
3157 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
);
3165 bi
->bi_error
= -EIO
;
3166 if (!raid5_dec_bi_active_stripes(bi
))
3167 bio_list_add(return_bi
, bi
);
3172 bitmap_endwrite(conf
->mddev
->bitmap
, sh
->sector
,
3173 STRIPE_SECTORS
, 0, 0);
3174 /* If we were in the middle of a write the parity block might
3175 * still be locked - so just clear all R5_LOCKED flags
3177 clear_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
3182 if (test_and_clear_bit(STRIPE_FULL_WRITE
, &sh
->state
))
3183 if (atomic_dec_and_test(&conf
->pending_full_writes
))
3184 md_wakeup_thread(conf
->mddev
->thread
);
3188 handle_failed_sync(struct r5conf
*conf
, struct stripe_head
*sh
,
3189 struct stripe_head_state
*s
)
3194 BUG_ON(sh
->batch_head
);
3195 clear_bit(STRIPE_SYNCING
, &sh
->state
);
3196 if (test_and_clear_bit(R5_Overlap
, &sh
->dev
[sh
->pd_idx
].flags
))
3197 wake_up(&conf
->wait_for_overlap
);
3200 /* There is nothing more to do for sync/check/repair.
3201 * Don't even need to abort as that is handled elsewhere
3202 * if needed, and not always wanted e.g. if there is a known
3204 * For recover/replace we need to record a bad block on all
3205 * non-sync devices, or abort the recovery
3207 if (test_bit(MD_RECOVERY_RECOVER
, &conf
->mddev
->recovery
)) {
3208 /* During recovery devices cannot be removed, so
3209 * locking and refcounting of rdevs is not needed
3211 for (i
= 0; i
< conf
->raid_disks
; i
++) {
3212 struct md_rdev
*rdev
= conf
->disks
[i
].rdev
;
3214 && !test_bit(Faulty
, &rdev
->flags
)
3215 && !test_bit(In_sync
, &rdev
->flags
)
3216 && !rdev_set_badblocks(rdev
, sh
->sector
,
3219 rdev
= conf
->disks
[i
].replacement
;
3221 && !test_bit(Faulty
, &rdev
->flags
)
3222 && !test_bit(In_sync
, &rdev
->flags
)
3223 && !rdev_set_badblocks(rdev
, sh
->sector
,
3228 conf
->recovery_disabled
=
3229 conf
->mddev
->recovery_disabled
;
3231 md_done_sync(conf
->mddev
, STRIPE_SECTORS
, !abort
);
3234 static int want_replace(struct stripe_head
*sh
, int disk_idx
)
3236 struct md_rdev
*rdev
;
3238 /* Doing recovery so rcu locking not required */
3239 rdev
= sh
->raid_conf
->disks
[disk_idx
].replacement
;
3241 && !test_bit(Faulty
, &rdev
->flags
)
3242 && !test_bit(In_sync
, &rdev
->flags
)
3243 && (rdev
->recovery_offset
<= sh
->sector
3244 || rdev
->mddev
->recovery_cp
<= sh
->sector
))
3250 /* fetch_block - checks the given member device to see if its data needs
3251 * to be read or computed to satisfy a request.
3253 * Returns 1 when no more member devices need to be checked, otherwise returns
3254 * 0 to tell the loop in handle_stripe_fill to continue
3257 static int need_this_block(struct stripe_head
*sh
, struct stripe_head_state
*s
,
3258 int disk_idx
, int disks
)
3260 struct r5dev
*dev
= &sh
->dev
[disk_idx
];
3261 struct r5dev
*fdev
[2] = { &sh
->dev
[s
->failed_num
[0]],
3262 &sh
->dev
[s
->failed_num
[1]] };
3266 if (test_bit(R5_LOCKED
, &dev
->flags
) ||
3267 test_bit(R5_UPTODATE
, &dev
->flags
))
3268 /* No point reading this as we already have it or have
3269 * decided to get it.
3274 (dev
->towrite
&& !test_bit(R5_OVERWRITE
, &dev
->flags
)))
3275 /* We need this block to directly satisfy a request */
3278 if (s
->syncing
|| s
->expanding
||
3279 (s
->replacing
&& want_replace(sh
, disk_idx
)))
3280 /* When syncing, or expanding we read everything.
3281 * When replacing, we need the replaced block.
3285 if ((s
->failed
>= 1 && fdev
[0]->toread
) ||
3286 (s
->failed
>= 2 && fdev
[1]->toread
))
3287 /* If we want to read from a failed device, then
3288 * we need to actually read every other device.
3292 /* Sometimes neither read-modify-write nor reconstruct-write
3293 * cycles can work. In those cases we read every block we
3294 * can. Then the parity-update is certain to have enough to
3296 * This can only be a problem when we need to write something,
3297 * and some device has failed. If either of those tests
3298 * fail we need look no further.
3300 if (!s
->failed
|| !s
->to_write
)
3303 if (test_bit(R5_Insync
, &dev
->flags
) &&
3304 !test_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
3305 /* Pre-reads at not permitted until after short delay
3306 * to gather multiple requests. However if this
3307 * device is no Insync, the block could only be be computed
3308 * and there is no need to delay that.
3312 for (i
= 0; i
< s
->failed
&& i
< 2; i
++) {
3313 if (fdev
[i
]->towrite
&&
3314 !test_bit(R5_UPTODATE
, &fdev
[i
]->flags
) &&
3315 !test_bit(R5_OVERWRITE
, &fdev
[i
]->flags
))
3316 /* If we have a partial write to a failed
3317 * device, then we will need to reconstruct
3318 * the content of that device, so all other
3319 * devices must be read.
3324 /* If we are forced to do a reconstruct-write, either because
3325 * the current RAID6 implementation only supports that, or
3326 * or because parity cannot be trusted and we are currently
3327 * recovering it, there is extra need to be careful.
3328 * If one of the devices that we would need to read, because
3329 * it is not being overwritten (and maybe not written at all)
3330 * is missing/faulty, then we need to read everything we can.
3332 if (sh
->raid_conf
->level
!= 6 &&
3333 sh
->sector
< sh
->raid_conf
->mddev
->recovery_cp
)
3334 /* reconstruct-write isn't being forced */
3336 for (i
= 0; i
< s
->failed
&& i
< 2; i
++) {
3337 if (s
->failed_num
[i
] != sh
->pd_idx
&&
3338 s
->failed_num
[i
] != sh
->qd_idx
&&
3339 !test_bit(R5_UPTODATE
, &fdev
[i
]->flags
) &&
3340 !test_bit(R5_OVERWRITE
, &fdev
[i
]->flags
))
3347 static int fetch_block(struct stripe_head
*sh
, struct stripe_head_state
*s
,
3348 int disk_idx
, int disks
)
3350 struct r5dev
*dev
= &sh
->dev
[disk_idx
];
3352 /* is the data in this block needed, and can we get it? */
3353 if (need_this_block(sh
, s
, disk_idx
, disks
)) {
3354 /* we would like to get this block, possibly by computing it,
3355 * otherwise read it if the backing disk is insync
3357 BUG_ON(test_bit(R5_Wantcompute
, &dev
->flags
));
3358 BUG_ON(test_bit(R5_Wantread
, &dev
->flags
));
3359 BUG_ON(sh
->batch_head
);
3360 if ((s
->uptodate
== disks
- 1) &&
3361 (s
->failed
&& (disk_idx
== s
->failed_num
[0] ||
3362 disk_idx
== s
->failed_num
[1]))) {
3363 /* have disk failed, and we're requested to fetch it;
3366 pr_debug("Computing stripe %llu block %d\n",
3367 (unsigned long long)sh
->sector
, disk_idx
);
3368 set_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
3369 set_bit(STRIPE_OP_COMPUTE_BLK
, &s
->ops_request
);
3370 set_bit(R5_Wantcompute
, &dev
->flags
);
3371 sh
->ops
.target
= disk_idx
;
3372 sh
->ops
.target2
= -1; /* no 2nd target */
3374 /* Careful: from this point on 'uptodate' is in the eye
3375 * of raid_run_ops which services 'compute' operations
3376 * before writes. R5_Wantcompute flags a block that will
3377 * be R5_UPTODATE by the time it is needed for a
3378 * subsequent operation.
3382 } else if (s
->uptodate
== disks
-2 && s
->failed
>= 2) {
3383 /* Computing 2-failure is *very* expensive; only
3384 * do it if failed >= 2
3387 for (other
= disks
; other
--; ) {
3388 if (other
== disk_idx
)
3390 if (!test_bit(R5_UPTODATE
,
3391 &sh
->dev
[other
].flags
))
3395 pr_debug("Computing stripe %llu blocks %d,%d\n",
3396 (unsigned long long)sh
->sector
,
3398 set_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
3399 set_bit(STRIPE_OP_COMPUTE_BLK
, &s
->ops_request
);
3400 set_bit(R5_Wantcompute
, &sh
->dev
[disk_idx
].flags
);
3401 set_bit(R5_Wantcompute
, &sh
->dev
[other
].flags
);
3402 sh
->ops
.target
= disk_idx
;
3403 sh
->ops
.target2
= other
;
3407 } else if (test_bit(R5_Insync
, &dev
->flags
)) {
3408 set_bit(R5_LOCKED
, &dev
->flags
);
3409 set_bit(R5_Wantread
, &dev
->flags
);
3411 pr_debug("Reading block %d (sync=%d)\n",
3412 disk_idx
, s
->syncing
);
3420 * handle_stripe_fill - read or compute data to satisfy pending requests.
3422 static void handle_stripe_fill(struct stripe_head
*sh
,
3423 struct stripe_head_state
*s
,
3428 /* look for blocks to read/compute, skip this if a compute
3429 * is already in flight, or if the stripe contents are in the
3430 * midst of changing due to a write
3432 if (!test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
) && !sh
->check_state
&&
3433 !sh
->reconstruct_state
)
3434 for (i
= disks
; i
--; )
3435 if (fetch_block(sh
, s
, i
, disks
))
3437 set_bit(STRIPE_HANDLE
, &sh
->state
);
3440 static void break_stripe_batch_list(struct stripe_head
*head_sh
,
3441 unsigned long handle_flags
);
3442 /* handle_stripe_clean_event
3443 * any written block on an uptodate or failed drive can be returned.
3444 * Note that if we 'wrote' to a failed drive, it will be UPTODATE, but
3445 * never LOCKED, so we don't need to test 'failed' directly.
3447 static void handle_stripe_clean_event(struct r5conf
*conf
,
3448 struct stripe_head
*sh
, int disks
, struct bio_list
*return_bi
)
3452 int discard_pending
= 0;
3453 struct stripe_head
*head_sh
= sh
;
3454 bool do_endio
= false;
3456 for (i
= disks
; i
--; )
3457 if (sh
->dev
[i
].written
) {
3459 if (!test_bit(R5_LOCKED
, &dev
->flags
) &&
3460 (test_bit(R5_UPTODATE
, &dev
->flags
) ||
3461 test_bit(R5_Discard
, &dev
->flags
) ||
3462 test_bit(R5_SkipCopy
, &dev
->flags
))) {
3463 /* We can return any write requests */
3464 struct bio
*wbi
, *wbi2
;
3465 pr_debug("Return write for disc %d\n", i
);
3466 if (test_and_clear_bit(R5_Discard
, &dev
->flags
))
3467 clear_bit(R5_UPTODATE
, &dev
->flags
);
3468 if (test_and_clear_bit(R5_SkipCopy
, &dev
->flags
)) {
3469 WARN_ON(test_bit(R5_UPTODATE
, &dev
->flags
));
3474 dev
->page
= dev
->orig_page
;
3476 dev
->written
= NULL
;
3477 while (wbi
&& wbi
->bi_iter
.bi_sector
<
3478 dev
->sector
+ STRIPE_SECTORS
) {
3479 wbi2
= r5_next_bio(wbi
, dev
->sector
);
3480 if (!raid5_dec_bi_active_stripes(wbi
)) {
3481 md_write_end(conf
->mddev
);
3482 bio_list_add(return_bi
, wbi
);
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
);
3507 r5l_stripe_write_finished(sh
);
3509 if (!discard_pending
&&
3510 test_bit(R5_Discard
, &sh
->dev
[sh
->pd_idx
].flags
)) {
3511 clear_bit(R5_Discard
, &sh
->dev
[sh
->pd_idx
].flags
);
3512 clear_bit(R5_UPTODATE
, &sh
->dev
[sh
->pd_idx
].flags
);
3513 if (sh
->qd_idx
>= 0) {
3514 clear_bit(R5_Discard
, &sh
->dev
[sh
->qd_idx
].flags
);
3515 clear_bit(R5_UPTODATE
, &sh
->dev
[sh
->qd_idx
].flags
);
3517 /* now that discard is done we can proceed with any sync */
3518 clear_bit(STRIPE_DISCARD
, &sh
->state
);
3520 * SCSI discard will change some bio fields and the stripe has
3521 * no updated data, so remove it from hash list and the stripe
3522 * will be reinitialized
3524 spin_lock_irq(&conf
->device_lock
);
3527 if (head_sh
->batch_head
) {
3528 sh
= list_first_entry(&sh
->batch_list
,
3529 struct stripe_head
, batch_list
);
3533 spin_unlock_irq(&conf
->device_lock
);
3536 if (test_bit(STRIPE_SYNC_REQUESTED
, &sh
->state
))
3537 set_bit(STRIPE_HANDLE
, &sh
->state
);
3541 if (test_and_clear_bit(STRIPE_FULL_WRITE
, &sh
->state
))
3542 if (atomic_dec_and_test(&conf
->pending_full_writes
))
3543 md_wakeup_thread(conf
->mddev
->thread
);
3545 if (head_sh
->batch_head
&& do_endio
)
3546 break_stripe_batch_list(head_sh
, STRIPE_EXPAND_SYNC_FLAGS
);
3549 static void handle_stripe_dirtying(struct r5conf
*conf
,
3550 struct stripe_head
*sh
,
3551 struct stripe_head_state
*s
,
3554 int rmw
= 0, rcw
= 0, i
;
3555 sector_t recovery_cp
= conf
->mddev
->recovery_cp
;
3557 /* Check whether resync is now happening or should start.
3558 * If yes, then the array is dirty (after unclean shutdown or
3559 * initial creation), so parity in some stripes might be inconsistent.
3560 * In this case, we need to always do reconstruct-write, to ensure
3561 * that in case of drive failure or read-error correction, we
3562 * generate correct data from the parity.
3564 if (conf
->rmw_level
== PARITY_DISABLE_RMW
||
3565 (recovery_cp
< MaxSector
&& sh
->sector
>= recovery_cp
&&
3567 /* Calculate the real rcw later - for now make it
3568 * look like rcw is cheaper
3571 pr_debug("force RCW rmw_level=%u, recovery_cp=%llu sh->sector=%llu\n",
3572 conf
->rmw_level
, (unsigned long long)recovery_cp
,
3573 (unsigned long long)sh
->sector
);
3574 } else for (i
= disks
; i
--; ) {
3575 /* would I have to read this buffer for read_modify_write */
3576 struct r5dev
*dev
= &sh
->dev
[i
];
3577 if ((dev
->towrite
|| i
== sh
->pd_idx
|| i
== sh
->qd_idx
) &&
3578 !test_bit(R5_LOCKED
, &dev
->flags
) &&
3579 !(test_bit(R5_UPTODATE
, &dev
->flags
) ||
3580 test_bit(R5_Wantcompute
, &dev
->flags
))) {
3581 if (test_bit(R5_Insync
, &dev
->flags
))
3584 rmw
+= 2*disks
; /* cannot read it */
3586 /* Would I have to read this buffer for reconstruct_write */
3587 if (!test_bit(R5_OVERWRITE
, &dev
->flags
) &&
3588 i
!= sh
->pd_idx
&& i
!= sh
->qd_idx
&&
3589 !test_bit(R5_LOCKED
, &dev
->flags
) &&
3590 !(test_bit(R5_UPTODATE
, &dev
->flags
) ||
3591 test_bit(R5_Wantcompute
, &dev
->flags
))) {
3592 if (test_bit(R5_Insync
, &dev
->flags
))
3598 pr_debug("for sector %llu, rmw=%d rcw=%d\n",
3599 (unsigned long long)sh
->sector
, rmw
, rcw
);
3600 set_bit(STRIPE_HANDLE
, &sh
->state
);
3601 if ((rmw
< rcw
|| (rmw
== rcw
&& conf
->rmw_level
== PARITY_ENABLE_RMW
)) && rmw
> 0) {
3602 /* prefer read-modify-write, but need to get some data */
3603 if (conf
->mddev
->queue
)
3604 blk_add_trace_msg(conf
->mddev
->queue
,
3605 "raid5 rmw %llu %d",
3606 (unsigned long long)sh
->sector
, rmw
);
3607 for (i
= disks
; i
--; ) {
3608 struct r5dev
*dev
= &sh
->dev
[i
];
3609 if ((dev
->towrite
|| i
== sh
->pd_idx
|| i
== sh
->qd_idx
) &&
3610 !test_bit(R5_LOCKED
, &dev
->flags
) &&
3611 !(test_bit(R5_UPTODATE
, &dev
->flags
) ||
3612 test_bit(R5_Wantcompute
, &dev
->flags
)) &&
3613 test_bit(R5_Insync
, &dev
->flags
)) {
3614 if (test_bit(STRIPE_PREREAD_ACTIVE
,
3616 pr_debug("Read_old block %d for r-m-w\n",
3618 set_bit(R5_LOCKED
, &dev
->flags
);
3619 set_bit(R5_Wantread
, &dev
->flags
);
3622 set_bit(STRIPE_DELAYED
, &sh
->state
);
3623 set_bit(STRIPE_HANDLE
, &sh
->state
);
3628 if ((rcw
< rmw
|| (rcw
== rmw
&& conf
->rmw_level
!= PARITY_ENABLE_RMW
)) && rcw
> 0) {
3629 /* want reconstruct write, but need to get some data */
3632 for (i
= disks
; i
--; ) {
3633 struct r5dev
*dev
= &sh
->dev
[i
];
3634 if (!test_bit(R5_OVERWRITE
, &dev
->flags
) &&
3635 i
!= sh
->pd_idx
&& i
!= sh
->qd_idx
&&
3636 !test_bit(R5_LOCKED
, &dev
->flags
) &&
3637 !(test_bit(R5_UPTODATE
, &dev
->flags
) ||
3638 test_bit(R5_Wantcompute
, &dev
->flags
))) {
3640 if (test_bit(R5_Insync
, &dev
->flags
) &&
3641 test_bit(STRIPE_PREREAD_ACTIVE
,
3643 pr_debug("Read_old block "
3644 "%d for Reconstruct\n", i
);
3645 set_bit(R5_LOCKED
, &dev
->flags
);
3646 set_bit(R5_Wantread
, &dev
->flags
);
3650 set_bit(STRIPE_DELAYED
, &sh
->state
);
3651 set_bit(STRIPE_HANDLE
, &sh
->state
);
3655 if (rcw
&& conf
->mddev
->queue
)
3656 blk_add_trace_msg(conf
->mddev
->queue
, "raid5 rcw %llu %d %d %d",
3657 (unsigned long long)sh
->sector
,
3658 rcw
, qread
, test_bit(STRIPE_DELAYED
, &sh
->state
));
3661 if (rcw
> disks
&& rmw
> disks
&&
3662 !test_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
3663 set_bit(STRIPE_DELAYED
, &sh
->state
);
3665 /* now if nothing is locked, and if we have enough data,
3666 * we can start a write request
3668 /* since handle_stripe can be called at any time we need to handle the
3669 * case where a compute block operation has been submitted and then a
3670 * subsequent call wants to start a write request. raid_run_ops only
3671 * handles the case where compute block and reconstruct are requested
3672 * simultaneously. If this is not the case then new writes need to be
3673 * held off until the compute completes.
3675 if ((s
->req_compute
|| !test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
)) &&
3676 (s
->locked
== 0 && (rcw
== 0 || rmw
== 0) &&
3677 !test_bit(STRIPE_BIT_DELAY
, &sh
->state
)))
3678 schedule_reconstruction(sh
, s
, rcw
== 0, 0);
3681 static void handle_parity_checks5(struct r5conf
*conf
, struct stripe_head
*sh
,
3682 struct stripe_head_state
*s
, int disks
)
3684 struct r5dev
*dev
= NULL
;
3686 BUG_ON(sh
->batch_head
);
3687 set_bit(STRIPE_HANDLE
, &sh
->state
);
3689 switch (sh
->check_state
) {
3690 case check_state_idle
:
3691 /* start a new check operation if there are no failures */
3692 if (s
->failed
== 0) {
3693 BUG_ON(s
->uptodate
!= disks
);
3694 sh
->check_state
= check_state_run
;
3695 set_bit(STRIPE_OP_CHECK
, &s
->ops_request
);
3696 clear_bit(R5_UPTODATE
, &sh
->dev
[sh
->pd_idx
].flags
);
3700 dev
= &sh
->dev
[s
->failed_num
[0]];
3702 case check_state_compute_result
:
3703 sh
->check_state
= check_state_idle
;
3705 dev
= &sh
->dev
[sh
->pd_idx
];
3707 /* check that a write has not made the stripe insync */
3708 if (test_bit(STRIPE_INSYNC
, &sh
->state
))
3711 /* either failed parity check, or recovery is happening */
3712 BUG_ON(!test_bit(R5_UPTODATE
, &dev
->flags
));
3713 BUG_ON(s
->uptodate
!= disks
);
3715 set_bit(R5_LOCKED
, &dev
->flags
);
3717 set_bit(R5_Wantwrite
, &dev
->flags
);
3719 clear_bit(STRIPE_DEGRADED
, &sh
->state
);
3720 set_bit(STRIPE_INSYNC
, &sh
->state
);
3722 case check_state_run
:
3723 break; /* we will be called again upon completion */
3724 case check_state_check_result
:
3725 sh
->check_state
= check_state_idle
;
3727 /* if a failure occurred during the check operation, leave
3728 * STRIPE_INSYNC not set and let the stripe be handled again
3733 /* handle a successful check operation, if parity is correct
3734 * we are done. Otherwise update the mismatch count and repair
3735 * parity if !MD_RECOVERY_CHECK
3737 if ((sh
->ops
.zero_sum_result
& SUM_CHECK_P_RESULT
) == 0)
3738 /* parity is correct (on disc,
3739 * not in buffer any more)
3741 set_bit(STRIPE_INSYNC
, &sh
->state
);
3743 atomic64_add(STRIPE_SECTORS
, &conf
->mddev
->resync_mismatches
);
3744 if (test_bit(MD_RECOVERY_CHECK
, &conf
->mddev
->recovery
))
3745 /* don't try to repair!! */
3746 set_bit(STRIPE_INSYNC
, &sh
->state
);
3748 sh
->check_state
= check_state_compute_run
;
3749 set_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
3750 set_bit(STRIPE_OP_COMPUTE_BLK
, &s
->ops_request
);
3751 set_bit(R5_Wantcompute
,
3752 &sh
->dev
[sh
->pd_idx
].flags
);
3753 sh
->ops
.target
= sh
->pd_idx
;
3754 sh
->ops
.target2
= -1;
3759 case check_state_compute_run
:
3762 printk(KERN_ERR
"%s: unknown check_state: %d sector: %llu\n",
3763 __func__
, sh
->check_state
,
3764 (unsigned long long) sh
->sector
);
3769 static void handle_parity_checks6(struct r5conf
*conf
, struct stripe_head
*sh
,
3770 struct stripe_head_state
*s
,
3773 int pd_idx
= sh
->pd_idx
;
3774 int qd_idx
= sh
->qd_idx
;
3777 BUG_ON(sh
->batch_head
);
3778 set_bit(STRIPE_HANDLE
, &sh
->state
);
3780 BUG_ON(s
->failed
> 2);
3782 /* Want to check and possibly repair P and Q.
3783 * However there could be one 'failed' device, in which
3784 * case we can only check one of them, possibly using the
3785 * other to generate missing data
3788 switch (sh
->check_state
) {
3789 case check_state_idle
:
3790 /* start a new check operation if there are < 2 failures */
3791 if (s
->failed
== s
->q_failed
) {
3792 /* The only possible failed device holds Q, so it
3793 * makes sense to check P (If anything else were failed,
3794 * we would have used P to recreate it).
3796 sh
->check_state
= check_state_run
;
3798 if (!s
->q_failed
&& s
->failed
< 2) {
3799 /* Q is not failed, and we didn't use it to generate
3800 * anything, so it makes sense to check it
3802 if (sh
->check_state
== check_state_run
)
3803 sh
->check_state
= check_state_run_pq
;
3805 sh
->check_state
= check_state_run_q
;
3808 /* discard potentially stale zero_sum_result */
3809 sh
->ops
.zero_sum_result
= 0;
3811 if (sh
->check_state
== check_state_run
) {
3812 /* async_xor_zero_sum destroys the contents of P */
3813 clear_bit(R5_UPTODATE
, &sh
->dev
[pd_idx
].flags
);
3816 if (sh
->check_state
>= check_state_run
&&
3817 sh
->check_state
<= check_state_run_pq
) {
3818 /* async_syndrome_zero_sum preserves P and Q, so
3819 * no need to mark them !uptodate here
3821 set_bit(STRIPE_OP_CHECK
, &s
->ops_request
);
3825 /* we have 2-disk failure */
3826 BUG_ON(s
->failed
!= 2);
3828 case check_state_compute_result
:
3829 sh
->check_state
= check_state_idle
;
3831 /* check that a write has not made the stripe insync */
3832 if (test_bit(STRIPE_INSYNC
, &sh
->state
))
3835 /* now write out any block on a failed drive,
3836 * or P or Q if they were recomputed
3838 BUG_ON(s
->uptodate
< disks
- 1); /* We don't need Q to recover */
3839 if (s
->failed
== 2) {
3840 dev
= &sh
->dev
[s
->failed_num
[1]];
3842 set_bit(R5_LOCKED
, &dev
->flags
);
3843 set_bit(R5_Wantwrite
, &dev
->flags
);
3845 if (s
->failed
>= 1) {
3846 dev
= &sh
->dev
[s
->failed_num
[0]];
3848 set_bit(R5_LOCKED
, &dev
->flags
);
3849 set_bit(R5_Wantwrite
, &dev
->flags
);
3851 if (sh
->ops
.zero_sum_result
& SUM_CHECK_P_RESULT
) {
3852 dev
= &sh
->dev
[pd_idx
];
3854 set_bit(R5_LOCKED
, &dev
->flags
);
3855 set_bit(R5_Wantwrite
, &dev
->flags
);
3857 if (sh
->ops
.zero_sum_result
& SUM_CHECK_Q_RESULT
) {
3858 dev
= &sh
->dev
[qd_idx
];
3860 set_bit(R5_LOCKED
, &dev
->flags
);
3861 set_bit(R5_Wantwrite
, &dev
->flags
);
3863 clear_bit(STRIPE_DEGRADED
, &sh
->state
);
3865 set_bit(STRIPE_INSYNC
, &sh
->state
);
3867 case check_state_run
:
3868 case check_state_run_q
:
3869 case check_state_run_pq
:
3870 break; /* we will be called again upon completion */
3871 case check_state_check_result
:
3872 sh
->check_state
= check_state_idle
;
3874 /* handle a successful check operation, if parity is correct
3875 * we are done. Otherwise update the mismatch count and repair
3876 * parity if !MD_RECOVERY_CHECK
3878 if (sh
->ops
.zero_sum_result
== 0) {
3879 /* both parities are correct */
3881 set_bit(STRIPE_INSYNC
, &sh
->state
);
3883 /* in contrast to the raid5 case we can validate
3884 * parity, but still have a failure to write
3887 sh
->check_state
= check_state_compute_result
;
3888 /* Returning at this point means that we may go
3889 * off and bring p and/or q uptodate again so
3890 * we make sure to check zero_sum_result again
3891 * to verify if p or q need writeback
3895 atomic64_add(STRIPE_SECTORS
, &conf
->mddev
->resync_mismatches
);
3896 if (test_bit(MD_RECOVERY_CHECK
, &conf
->mddev
->recovery
))
3897 /* don't try to repair!! */
3898 set_bit(STRIPE_INSYNC
, &sh
->state
);
3900 int *target
= &sh
->ops
.target
;
3902 sh
->ops
.target
= -1;
3903 sh
->ops
.target2
= -1;
3904 sh
->check_state
= check_state_compute_run
;
3905 set_bit(STRIPE_COMPUTE_RUN
, &sh
->state
);
3906 set_bit(STRIPE_OP_COMPUTE_BLK
, &s
->ops_request
);
3907 if (sh
->ops
.zero_sum_result
& SUM_CHECK_P_RESULT
) {
3908 set_bit(R5_Wantcompute
,
3909 &sh
->dev
[pd_idx
].flags
);
3911 target
= &sh
->ops
.target2
;
3914 if (sh
->ops
.zero_sum_result
& SUM_CHECK_Q_RESULT
) {
3915 set_bit(R5_Wantcompute
,
3916 &sh
->dev
[qd_idx
].flags
);
3923 case check_state_compute_run
:
3926 printk(KERN_ERR
"%s: unknown check_state: %d sector: %llu\n",
3927 __func__
, sh
->check_state
,
3928 (unsigned long long) sh
->sector
);
3933 static void handle_stripe_expansion(struct r5conf
*conf
, struct stripe_head
*sh
)
3937 /* We have read all the blocks in this stripe and now we need to
3938 * copy some of them into a target stripe for expand.
3940 struct dma_async_tx_descriptor
*tx
= NULL
;
3941 BUG_ON(sh
->batch_head
);
3942 clear_bit(STRIPE_EXPAND_SOURCE
, &sh
->state
);
3943 for (i
= 0; i
< sh
->disks
; i
++)
3944 if (i
!= sh
->pd_idx
&& i
!= sh
->qd_idx
) {
3946 struct stripe_head
*sh2
;
3947 struct async_submit_ctl submit
;
3949 sector_t bn
= raid5_compute_blocknr(sh
, i
, 1);
3950 sector_t s
= raid5_compute_sector(conf
, bn
, 0,
3952 sh2
= raid5_get_active_stripe(conf
, s
, 0, 1, 1);
3954 /* so far only the early blocks of this stripe
3955 * have been requested. When later blocks
3956 * get requested, we will try again
3959 if (!test_bit(STRIPE_EXPANDING
, &sh2
->state
) ||
3960 test_bit(R5_Expanded
, &sh2
->dev
[dd_idx
].flags
)) {
3961 /* must have already done this block */
3962 raid5_release_stripe(sh2
);
3966 /* place all the copies on one channel */
3967 init_async_submit(&submit
, 0, tx
, NULL
, NULL
, NULL
);
3968 tx
= async_memcpy(sh2
->dev
[dd_idx
].page
,
3969 sh
->dev
[i
].page
, 0, 0, STRIPE_SIZE
,
3972 set_bit(R5_Expanded
, &sh2
->dev
[dd_idx
].flags
);
3973 set_bit(R5_UPTODATE
, &sh2
->dev
[dd_idx
].flags
);
3974 for (j
= 0; j
< conf
->raid_disks
; j
++)
3975 if (j
!= sh2
->pd_idx
&&
3977 !test_bit(R5_Expanded
, &sh2
->dev
[j
].flags
))
3979 if (j
== conf
->raid_disks
) {
3980 set_bit(STRIPE_EXPAND_READY
, &sh2
->state
);
3981 set_bit(STRIPE_HANDLE
, &sh2
->state
);
3983 raid5_release_stripe(sh2
);
3986 /* done submitting copies, wait for them to complete */
3987 async_tx_quiesce(&tx
);
3991 * handle_stripe - do things to a stripe.
3993 * We lock the stripe by setting STRIPE_ACTIVE and then examine the
3994 * state of various bits to see what needs to be done.
3996 * return some read requests which now have data
3997 * return some write requests which are safely on storage
3998 * schedule a read on some buffers
3999 * schedule a write of some buffers
4000 * return confirmation of parity correctness
4004 static void analyse_stripe(struct stripe_head
*sh
, struct stripe_head_state
*s
)
4006 struct r5conf
*conf
= sh
->raid_conf
;
4007 int disks
= sh
->disks
;
4010 int do_recovery
= 0;
4012 memset(s
, 0, sizeof(*s
));
4014 s
->expanding
= test_bit(STRIPE_EXPAND_SOURCE
, &sh
->state
) && !sh
->batch_head
;
4015 s
->expanded
= test_bit(STRIPE_EXPAND_READY
, &sh
->state
) && !sh
->batch_head
;
4016 s
->failed_num
[0] = -1;
4017 s
->failed_num
[1] = -1;
4019 /* Now to look around and see what can be done */
4021 for (i
=disks
; i
--; ) {
4022 struct md_rdev
*rdev
;
4029 pr_debug("check %d: state 0x%lx read %p write %p written %p\n",
4031 dev
->toread
, dev
->towrite
, dev
->written
);
4032 /* maybe we can reply to a read
4034 * new wantfill requests are only permitted while
4035 * ops_complete_biofill is guaranteed to be inactive
4037 if (test_bit(R5_UPTODATE
, &dev
->flags
) && dev
->toread
&&
4038 !test_bit(STRIPE_BIOFILL_RUN
, &sh
->state
))
4039 set_bit(R5_Wantfill
, &dev
->flags
);
4041 /* now count some things */
4042 if (test_bit(R5_LOCKED
, &dev
->flags
))
4044 if (test_bit(R5_UPTODATE
, &dev
->flags
))
4046 if (test_bit(R5_Wantcompute
, &dev
->flags
)) {
4048 BUG_ON(s
->compute
> 2);
4051 if (test_bit(R5_Wantfill
, &dev
->flags
))
4053 else if (dev
->toread
)
4057 if (!test_bit(R5_OVERWRITE
, &dev
->flags
))
4062 /* Prefer to use the replacement for reads, but only
4063 * if it is recovered enough and has no bad blocks.
4065 rdev
= rcu_dereference(conf
->disks
[i
].replacement
);
4066 if (rdev
&& !test_bit(Faulty
, &rdev
->flags
) &&
4067 rdev
->recovery_offset
>= sh
->sector
+ STRIPE_SECTORS
&&
4068 !is_badblock(rdev
, sh
->sector
, STRIPE_SECTORS
,
4069 &first_bad
, &bad_sectors
))
4070 set_bit(R5_ReadRepl
, &dev
->flags
);
4072 if (rdev
&& !test_bit(Faulty
, &rdev
->flags
))
4073 set_bit(R5_NeedReplace
, &dev
->flags
);
4075 clear_bit(R5_NeedReplace
, &dev
->flags
);
4076 rdev
= rcu_dereference(conf
->disks
[i
].rdev
);
4077 clear_bit(R5_ReadRepl
, &dev
->flags
);
4079 if (rdev
&& test_bit(Faulty
, &rdev
->flags
))
4082 is_bad
= is_badblock(rdev
, sh
->sector
, STRIPE_SECTORS
,
4083 &first_bad
, &bad_sectors
);
4084 if (s
->blocked_rdev
== NULL
4085 && (test_bit(Blocked
, &rdev
->flags
)
4088 set_bit(BlockedBadBlocks
,
4090 s
->blocked_rdev
= rdev
;
4091 atomic_inc(&rdev
->nr_pending
);
4094 clear_bit(R5_Insync
, &dev
->flags
);
4098 /* also not in-sync */
4099 if (!test_bit(WriteErrorSeen
, &rdev
->flags
) &&
4100 test_bit(R5_UPTODATE
, &dev
->flags
)) {
4101 /* treat as in-sync, but with a read error
4102 * which we can now try to correct
4104 set_bit(R5_Insync
, &dev
->flags
);
4105 set_bit(R5_ReadError
, &dev
->flags
);
4107 } else if (test_bit(In_sync
, &rdev
->flags
))
4108 set_bit(R5_Insync
, &dev
->flags
);
4109 else if (sh
->sector
+ STRIPE_SECTORS
<= rdev
->recovery_offset
)
4110 /* in sync if before recovery_offset */
4111 set_bit(R5_Insync
, &dev
->flags
);
4112 else if (test_bit(R5_UPTODATE
, &dev
->flags
) &&
4113 test_bit(R5_Expanded
, &dev
->flags
))
4114 /* If we've reshaped into here, we assume it is Insync.
4115 * We will shortly update recovery_offset to make
4118 set_bit(R5_Insync
, &dev
->flags
);
4120 if (test_bit(R5_WriteError
, &dev
->flags
)) {
4121 /* This flag does not apply to '.replacement'
4122 * only to .rdev, so make sure to check that*/
4123 struct md_rdev
*rdev2
= rcu_dereference(
4124 conf
->disks
[i
].rdev
);
4126 clear_bit(R5_Insync
, &dev
->flags
);
4127 if (rdev2
&& !test_bit(Faulty
, &rdev2
->flags
)) {
4128 s
->handle_bad_blocks
= 1;
4129 atomic_inc(&rdev2
->nr_pending
);
4131 clear_bit(R5_WriteError
, &dev
->flags
);
4133 if (test_bit(R5_MadeGood
, &dev
->flags
)) {
4134 /* This flag does not apply to '.replacement'
4135 * only to .rdev, so make sure to check that*/
4136 struct md_rdev
*rdev2
= rcu_dereference(
4137 conf
->disks
[i
].rdev
);
4138 if (rdev2
&& !test_bit(Faulty
, &rdev2
->flags
)) {
4139 s
->handle_bad_blocks
= 1;
4140 atomic_inc(&rdev2
->nr_pending
);
4142 clear_bit(R5_MadeGood
, &dev
->flags
);
4144 if (test_bit(R5_MadeGoodRepl
, &dev
->flags
)) {
4145 struct md_rdev
*rdev2
= rcu_dereference(
4146 conf
->disks
[i
].replacement
);
4147 if (rdev2
&& !test_bit(Faulty
, &rdev2
->flags
)) {
4148 s
->handle_bad_blocks
= 1;
4149 atomic_inc(&rdev2
->nr_pending
);
4151 clear_bit(R5_MadeGoodRepl
, &dev
->flags
);
4153 if (!test_bit(R5_Insync
, &dev
->flags
)) {
4154 /* The ReadError flag will just be confusing now */
4155 clear_bit(R5_ReadError
, &dev
->flags
);
4156 clear_bit(R5_ReWrite
, &dev
->flags
);
4158 if (test_bit(R5_ReadError
, &dev
->flags
))
4159 clear_bit(R5_Insync
, &dev
->flags
);
4160 if (!test_bit(R5_Insync
, &dev
->flags
)) {
4162 s
->failed_num
[s
->failed
] = i
;
4164 if (rdev
&& !test_bit(Faulty
, &rdev
->flags
))
4168 if (test_bit(STRIPE_SYNCING
, &sh
->state
)) {
4169 /* If there is a failed device being replaced,
4170 * we must be recovering.
4171 * else if we are after recovery_cp, we must be syncing
4172 * else if MD_RECOVERY_REQUESTED is set, we also are syncing.
4173 * else we can only be replacing
4174 * sync and recovery both need to read all devices, and so
4175 * use the same flag.
4178 sh
->sector
>= conf
->mddev
->recovery_cp
||
4179 test_bit(MD_RECOVERY_REQUESTED
, &(conf
->mddev
->recovery
)))
4187 static int clear_batch_ready(struct stripe_head
*sh
)
4189 /* Return '1' if this is a member of batch, or
4190 * '0' if it is a lone stripe or a head which can now be
4193 struct stripe_head
*tmp
;
4194 if (!test_and_clear_bit(STRIPE_BATCH_READY
, &sh
->state
))
4195 return (sh
->batch_head
&& sh
->batch_head
!= sh
);
4196 spin_lock(&sh
->stripe_lock
);
4197 if (!sh
->batch_head
) {
4198 spin_unlock(&sh
->stripe_lock
);
4203 * this stripe could be added to a batch list before we check
4204 * BATCH_READY, skips it
4206 if (sh
->batch_head
!= sh
) {
4207 spin_unlock(&sh
->stripe_lock
);
4210 spin_lock(&sh
->batch_lock
);
4211 list_for_each_entry(tmp
, &sh
->batch_list
, batch_list
)
4212 clear_bit(STRIPE_BATCH_READY
, &tmp
->state
);
4213 spin_unlock(&sh
->batch_lock
);
4214 spin_unlock(&sh
->stripe_lock
);
4217 * BATCH_READY is cleared, no new stripes can be added.
4218 * batch_list can be accessed without lock
4223 static void break_stripe_batch_list(struct stripe_head
*head_sh
,
4224 unsigned long handle_flags
)
4226 struct stripe_head
*sh
, *next
;
4230 list_for_each_entry_safe(sh
, next
, &head_sh
->batch_list
, batch_list
) {
4232 list_del_init(&sh
->batch_list
);
4234 WARN_ON_ONCE(sh
->state
& ((1 << STRIPE_ACTIVE
) |
4235 (1 << STRIPE_SYNCING
) |
4236 (1 << STRIPE_REPLACED
) |
4237 (1 << STRIPE_PREREAD_ACTIVE
) |
4238 (1 << STRIPE_DELAYED
) |
4239 (1 << STRIPE_BIT_DELAY
) |
4240 (1 << STRIPE_FULL_WRITE
) |
4241 (1 << STRIPE_BIOFILL_RUN
) |
4242 (1 << STRIPE_COMPUTE_RUN
) |
4243 (1 << STRIPE_OPS_REQ_PENDING
) |
4244 (1 << STRIPE_DISCARD
) |
4245 (1 << STRIPE_BATCH_READY
) |
4246 (1 << STRIPE_BATCH_ERR
) |
4247 (1 << STRIPE_BITMAP_PENDING
)));
4248 WARN_ON_ONCE(head_sh
->state
& ((1 << STRIPE_DISCARD
) |
4249 (1 << STRIPE_REPLACED
)));
4251 set_mask_bits(&sh
->state
, ~(STRIPE_EXPAND_SYNC_FLAGS
|
4252 (1 << STRIPE_DEGRADED
)),
4253 head_sh
->state
& (1 << STRIPE_INSYNC
));
4255 sh
->check_state
= head_sh
->check_state
;
4256 sh
->reconstruct_state
= head_sh
->reconstruct_state
;
4257 for (i
= 0; i
< sh
->disks
; i
++) {
4258 if (test_and_clear_bit(R5_Overlap
, &sh
->dev
[i
].flags
))
4260 sh
->dev
[i
].flags
= head_sh
->dev
[i
].flags
&
4261 (~((1 << R5_WriteError
) | (1 << R5_Overlap
)));
4263 spin_lock_irq(&sh
->stripe_lock
);
4264 sh
->batch_head
= NULL
;
4265 spin_unlock_irq(&sh
->stripe_lock
);
4266 if (handle_flags
== 0 ||
4267 sh
->state
& handle_flags
)
4268 set_bit(STRIPE_HANDLE
, &sh
->state
);
4269 raid5_release_stripe(sh
);
4271 spin_lock_irq(&head_sh
->stripe_lock
);
4272 head_sh
->batch_head
= NULL
;
4273 spin_unlock_irq(&head_sh
->stripe_lock
);
4274 for (i
= 0; i
< head_sh
->disks
; i
++)
4275 if (test_and_clear_bit(R5_Overlap
, &head_sh
->dev
[i
].flags
))
4277 if (head_sh
->state
& handle_flags
)
4278 set_bit(STRIPE_HANDLE
, &head_sh
->state
);
4281 wake_up(&head_sh
->raid_conf
->wait_for_overlap
);
4284 static void handle_stripe(struct stripe_head
*sh
)
4286 struct stripe_head_state s
;
4287 struct r5conf
*conf
= sh
->raid_conf
;
4290 int disks
= sh
->disks
;
4291 struct r5dev
*pdev
, *qdev
;
4293 clear_bit(STRIPE_HANDLE
, &sh
->state
);
4294 if (test_and_set_bit_lock(STRIPE_ACTIVE
, &sh
->state
)) {
4295 /* already being handled, ensure it gets handled
4296 * again when current action finishes */
4297 set_bit(STRIPE_HANDLE
, &sh
->state
);
4301 if (clear_batch_ready(sh
) ) {
4302 clear_bit_unlock(STRIPE_ACTIVE
, &sh
->state
);
4306 if (test_and_clear_bit(STRIPE_BATCH_ERR
, &sh
->state
))
4307 break_stripe_batch_list(sh
, 0);
4309 if (test_bit(STRIPE_SYNC_REQUESTED
, &sh
->state
) && !sh
->batch_head
) {
4310 spin_lock(&sh
->stripe_lock
);
4311 /* Cannot process 'sync' concurrently with 'discard' */
4312 if (!test_bit(STRIPE_DISCARD
, &sh
->state
) &&
4313 test_and_clear_bit(STRIPE_SYNC_REQUESTED
, &sh
->state
)) {
4314 set_bit(STRIPE_SYNCING
, &sh
->state
);
4315 clear_bit(STRIPE_INSYNC
, &sh
->state
);
4316 clear_bit(STRIPE_REPLACED
, &sh
->state
);
4318 spin_unlock(&sh
->stripe_lock
);
4320 clear_bit(STRIPE_DELAYED
, &sh
->state
);
4322 pr_debug("handling stripe %llu, state=%#lx cnt=%d, "
4323 "pd_idx=%d, qd_idx=%d\n, check:%d, reconstruct:%d\n",
4324 (unsigned long long)sh
->sector
, sh
->state
,
4325 atomic_read(&sh
->count
), sh
->pd_idx
, sh
->qd_idx
,
4326 sh
->check_state
, sh
->reconstruct_state
);
4328 analyse_stripe(sh
, &s
);
4330 if (test_bit(STRIPE_LOG_TRAPPED
, &sh
->state
))
4333 if (s
.handle_bad_blocks
) {
4334 set_bit(STRIPE_HANDLE
, &sh
->state
);
4338 if (unlikely(s
.blocked_rdev
)) {
4339 if (s
.syncing
|| s
.expanding
|| s
.expanded
||
4340 s
.replacing
|| s
.to_write
|| s
.written
) {
4341 set_bit(STRIPE_HANDLE
, &sh
->state
);
4344 /* There is nothing for the blocked_rdev to block */
4345 rdev_dec_pending(s
.blocked_rdev
, conf
->mddev
);
4346 s
.blocked_rdev
= NULL
;
4349 if (s
.to_fill
&& !test_bit(STRIPE_BIOFILL_RUN
, &sh
->state
)) {
4350 set_bit(STRIPE_OP_BIOFILL
, &s
.ops_request
);
4351 set_bit(STRIPE_BIOFILL_RUN
, &sh
->state
);
4354 pr_debug("locked=%d uptodate=%d to_read=%d"
4355 " to_write=%d failed=%d failed_num=%d,%d\n",
4356 s
.locked
, s
.uptodate
, s
.to_read
, s
.to_write
, s
.failed
,
4357 s
.failed_num
[0], s
.failed_num
[1]);
4358 /* check if the array has lost more than max_degraded devices and,
4359 * if so, some requests might need to be failed.
4361 if (s
.failed
> conf
->max_degraded
) {
4362 sh
->check_state
= 0;
4363 sh
->reconstruct_state
= 0;
4364 break_stripe_batch_list(sh
, 0);
4365 if (s
.to_read
+s
.to_write
+s
.written
)
4366 handle_failed_stripe(conf
, sh
, &s
, disks
, &s
.return_bi
);
4367 if (s
.syncing
+ s
.replacing
)
4368 handle_failed_sync(conf
, sh
, &s
);
4371 /* Now we check to see if any write operations have recently
4375 if (sh
->reconstruct_state
== reconstruct_state_prexor_drain_result
)
4377 if (sh
->reconstruct_state
== reconstruct_state_drain_result
||
4378 sh
->reconstruct_state
== reconstruct_state_prexor_drain_result
) {
4379 sh
->reconstruct_state
= reconstruct_state_idle
;
4381 /* All the 'written' buffers and the parity block are ready to
4382 * be written back to disk
4384 BUG_ON(!test_bit(R5_UPTODATE
, &sh
->dev
[sh
->pd_idx
].flags
) &&
4385 !test_bit(R5_Discard
, &sh
->dev
[sh
->pd_idx
].flags
));
4386 BUG_ON(sh
->qd_idx
>= 0 &&
4387 !test_bit(R5_UPTODATE
, &sh
->dev
[sh
->qd_idx
].flags
) &&
4388 !test_bit(R5_Discard
, &sh
->dev
[sh
->qd_idx
].flags
));
4389 for (i
= disks
; i
--; ) {
4390 struct r5dev
*dev
= &sh
->dev
[i
];
4391 if (test_bit(R5_LOCKED
, &dev
->flags
) &&
4392 (i
== sh
->pd_idx
|| i
== sh
->qd_idx
||
4394 pr_debug("Writing block %d\n", i
);
4395 set_bit(R5_Wantwrite
, &dev
->flags
);
4400 if (!test_bit(R5_Insync
, &dev
->flags
) ||
4401 ((i
== sh
->pd_idx
|| i
== sh
->qd_idx
) &&
4403 set_bit(STRIPE_INSYNC
, &sh
->state
);
4406 if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
4407 s
.dec_preread_active
= 1;
4411 * might be able to return some write requests if the parity blocks
4412 * are safe, or on a failed drive
4414 pdev
= &sh
->dev
[sh
->pd_idx
];
4415 s
.p_failed
= (s
.failed
>= 1 && s
.failed_num
[0] == sh
->pd_idx
)
4416 || (s
.failed
>= 2 && s
.failed_num
[1] == sh
->pd_idx
);
4417 qdev
= &sh
->dev
[sh
->qd_idx
];
4418 s
.q_failed
= (s
.failed
>= 1 && s
.failed_num
[0] == sh
->qd_idx
)
4419 || (s
.failed
>= 2 && s
.failed_num
[1] == sh
->qd_idx
)
4423 (s
.p_failed
|| ((test_bit(R5_Insync
, &pdev
->flags
)
4424 && !test_bit(R5_LOCKED
, &pdev
->flags
)
4425 && (test_bit(R5_UPTODATE
, &pdev
->flags
) ||
4426 test_bit(R5_Discard
, &pdev
->flags
))))) &&
4427 (s
.q_failed
|| ((test_bit(R5_Insync
, &qdev
->flags
)
4428 && !test_bit(R5_LOCKED
, &qdev
->flags
)
4429 && (test_bit(R5_UPTODATE
, &qdev
->flags
) ||
4430 test_bit(R5_Discard
, &qdev
->flags
))))))
4431 handle_stripe_clean_event(conf
, sh
, disks
, &s
.return_bi
);
4433 /* Now we might consider reading some blocks, either to check/generate
4434 * parity, or to satisfy requests
4435 * or to load a block that is being partially written.
4437 if (s
.to_read
|| s
.non_overwrite
4438 || (conf
->level
== 6 && s
.to_write
&& s
.failed
)
4439 || (s
.syncing
&& (s
.uptodate
+ s
.compute
< disks
))
4442 handle_stripe_fill(sh
, &s
, disks
);
4444 /* Now to consider new write requests and what else, if anything
4445 * should be read. We do not handle new writes when:
4446 * 1/ A 'write' operation (copy+xor) is already in flight.
4447 * 2/ A 'check' operation is in flight, as it may clobber the parity
4450 if (s
.to_write
&& !sh
->reconstruct_state
&& !sh
->check_state
)
4451 handle_stripe_dirtying(conf
, sh
, &s
, disks
);
4453 /* maybe we need to check and possibly fix the parity for this stripe
4454 * Any reads will already have been scheduled, so we just see if enough
4455 * data is available. The parity check is held off while parity
4456 * dependent operations are in flight.
4458 if (sh
->check_state
||
4459 (s
.syncing
&& s
.locked
== 0 &&
4460 !test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
) &&
4461 !test_bit(STRIPE_INSYNC
, &sh
->state
))) {
4462 if (conf
->level
== 6)
4463 handle_parity_checks6(conf
, sh
, &s
, disks
);
4465 handle_parity_checks5(conf
, sh
, &s
, disks
);
4468 if ((s
.replacing
|| s
.syncing
) && s
.locked
== 0
4469 && !test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
)
4470 && !test_bit(STRIPE_REPLACED
, &sh
->state
)) {
4471 /* Write out to replacement devices where possible */
4472 for (i
= 0; i
< conf
->raid_disks
; i
++)
4473 if (test_bit(R5_NeedReplace
, &sh
->dev
[i
].flags
)) {
4474 WARN_ON(!test_bit(R5_UPTODATE
, &sh
->dev
[i
].flags
));
4475 set_bit(R5_WantReplace
, &sh
->dev
[i
].flags
);
4476 set_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
4480 set_bit(STRIPE_INSYNC
, &sh
->state
);
4481 set_bit(STRIPE_REPLACED
, &sh
->state
);
4483 if ((s
.syncing
|| s
.replacing
) && s
.locked
== 0 &&
4484 !test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
) &&
4485 test_bit(STRIPE_INSYNC
, &sh
->state
)) {
4486 md_done_sync(conf
->mddev
, STRIPE_SECTORS
, 1);
4487 clear_bit(STRIPE_SYNCING
, &sh
->state
);
4488 if (test_and_clear_bit(R5_Overlap
, &sh
->dev
[sh
->pd_idx
].flags
))
4489 wake_up(&conf
->wait_for_overlap
);
4492 /* If the failed drives are just a ReadError, then we might need
4493 * to progress the repair/check process
4495 if (s
.failed
<= conf
->max_degraded
&& !conf
->mddev
->ro
)
4496 for (i
= 0; i
< s
.failed
; i
++) {
4497 struct r5dev
*dev
= &sh
->dev
[s
.failed_num
[i
]];
4498 if (test_bit(R5_ReadError
, &dev
->flags
)
4499 && !test_bit(R5_LOCKED
, &dev
->flags
)
4500 && test_bit(R5_UPTODATE
, &dev
->flags
)
4502 if (!test_bit(R5_ReWrite
, &dev
->flags
)) {
4503 set_bit(R5_Wantwrite
, &dev
->flags
);
4504 set_bit(R5_ReWrite
, &dev
->flags
);
4505 set_bit(R5_LOCKED
, &dev
->flags
);
4508 /* let's read it back */
4509 set_bit(R5_Wantread
, &dev
->flags
);
4510 set_bit(R5_LOCKED
, &dev
->flags
);
4516 /* Finish reconstruct operations initiated by the expansion process */
4517 if (sh
->reconstruct_state
== reconstruct_state_result
) {
4518 struct stripe_head
*sh_src
4519 = raid5_get_active_stripe(conf
, sh
->sector
, 1, 1, 1);
4520 if (sh_src
&& test_bit(STRIPE_EXPAND_SOURCE
, &sh_src
->state
)) {
4521 /* sh cannot be written until sh_src has been read.
4522 * so arrange for sh to be delayed a little
4524 set_bit(STRIPE_DELAYED
, &sh
->state
);
4525 set_bit(STRIPE_HANDLE
, &sh
->state
);
4526 if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE
,
4528 atomic_inc(&conf
->preread_active_stripes
);
4529 raid5_release_stripe(sh_src
);
4533 raid5_release_stripe(sh_src
);
4535 sh
->reconstruct_state
= reconstruct_state_idle
;
4536 clear_bit(STRIPE_EXPANDING
, &sh
->state
);
4537 for (i
= conf
->raid_disks
; i
--; ) {
4538 set_bit(R5_Wantwrite
, &sh
->dev
[i
].flags
);
4539 set_bit(R5_LOCKED
, &sh
->dev
[i
].flags
);
4544 if (s
.expanded
&& test_bit(STRIPE_EXPANDING
, &sh
->state
) &&
4545 !sh
->reconstruct_state
) {
4546 /* Need to write out all blocks after computing parity */
4547 sh
->disks
= conf
->raid_disks
;
4548 stripe_set_idx(sh
->sector
, conf
, 0, sh
);
4549 schedule_reconstruction(sh
, &s
, 1, 1);
4550 } else if (s
.expanded
&& !sh
->reconstruct_state
&& s
.locked
== 0) {
4551 clear_bit(STRIPE_EXPAND_READY
, &sh
->state
);
4552 atomic_dec(&conf
->reshape_stripes
);
4553 wake_up(&conf
->wait_for_overlap
);
4554 md_done_sync(conf
->mddev
, STRIPE_SECTORS
, 1);
4557 if (s
.expanding
&& s
.locked
== 0 &&
4558 !test_bit(STRIPE_COMPUTE_RUN
, &sh
->state
))
4559 handle_stripe_expansion(conf
, sh
);
4562 /* wait for this device to become unblocked */
4563 if (unlikely(s
.blocked_rdev
)) {
4564 if (conf
->mddev
->external
)
4565 md_wait_for_blocked_rdev(s
.blocked_rdev
,
4568 /* Internal metadata will immediately
4569 * be written by raid5d, so we don't
4570 * need to wait here.
4572 rdev_dec_pending(s
.blocked_rdev
,
4576 if (s
.handle_bad_blocks
)
4577 for (i
= disks
; i
--; ) {
4578 struct md_rdev
*rdev
;
4579 struct r5dev
*dev
= &sh
->dev
[i
];
4580 if (test_and_clear_bit(R5_WriteError
, &dev
->flags
)) {
4581 /* We own a safe reference to the rdev */
4582 rdev
= conf
->disks
[i
].rdev
;
4583 if (!rdev_set_badblocks(rdev
, sh
->sector
,
4585 md_error(conf
->mddev
, rdev
);
4586 rdev_dec_pending(rdev
, conf
->mddev
);
4588 if (test_and_clear_bit(R5_MadeGood
, &dev
->flags
)) {
4589 rdev
= conf
->disks
[i
].rdev
;
4590 rdev_clear_badblocks(rdev
, sh
->sector
,
4592 rdev_dec_pending(rdev
, conf
->mddev
);
4594 if (test_and_clear_bit(R5_MadeGoodRepl
, &dev
->flags
)) {
4595 rdev
= conf
->disks
[i
].replacement
;
4597 /* rdev have been moved down */
4598 rdev
= conf
->disks
[i
].rdev
;
4599 rdev_clear_badblocks(rdev
, sh
->sector
,
4601 rdev_dec_pending(rdev
, conf
->mddev
);
4606 raid_run_ops(sh
, s
.ops_request
);
4610 if (s
.dec_preread_active
) {
4611 /* We delay this until after ops_run_io so that if make_request
4612 * is waiting on a flush, it won't continue until the writes
4613 * have actually been submitted.
4615 atomic_dec(&conf
->preread_active_stripes
);
4616 if (atomic_read(&conf
->preread_active_stripes
) <
4618 md_wakeup_thread(conf
->mddev
->thread
);
4621 if (!bio_list_empty(&s
.return_bi
)) {
4622 if (test_bit(MD_CHANGE_PENDING
, &conf
->mddev
->flags
)) {
4623 spin_lock_irq(&conf
->device_lock
);
4624 bio_list_merge(&conf
->return_bi
, &s
.return_bi
);
4625 spin_unlock_irq(&conf
->device_lock
);
4626 md_wakeup_thread(conf
->mddev
->thread
);
4628 return_io(&s
.return_bi
);
4631 clear_bit_unlock(STRIPE_ACTIVE
, &sh
->state
);
4634 static void raid5_activate_delayed(struct r5conf
*conf
)
4636 if (atomic_read(&conf
->preread_active_stripes
) < IO_THRESHOLD
) {
4637 while (!list_empty(&conf
->delayed_list
)) {
4638 struct list_head
*l
= conf
->delayed_list
.next
;
4639 struct stripe_head
*sh
;
4640 sh
= list_entry(l
, struct stripe_head
, lru
);
4642 clear_bit(STRIPE_DELAYED
, &sh
->state
);
4643 if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
4644 atomic_inc(&conf
->preread_active_stripes
);
4645 list_add_tail(&sh
->lru
, &conf
->hold_list
);
4646 raid5_wakeup_stripe_thread(sh
);
4651 static void activate_bit_delay(struct r5conf
*conf
,
4652 struct list_head
*temp_inactive_list
)
4654 /* device_lock is held */
4655 struct list_head head
;
4656 list_add(&head
, &conf
->bitmap_list
);
4657 list_del_init(&conf
->bitmap_list
);
4658 while (!list_empty(&head
)) {
4659 struct stripe_head
*sh
= list_entry(head
.next
, struct stripe_head
, lru
);
4661 list_del_init(&sh
->lru
);
4662 atomic_inc(&sh
->count
);
4663 hash
= sh
->hash_lock_index
;
4664 __release_stripe(conf
, sh
, &temp_inactive_list
[hash
]);
4668 static int raid5_congested(struct mddev
*mddev
, int bits
)
4670 struct r5conf
*conf
= mddev
->private;
4672 /* No difference between reads and writes. Just check
4673 * how busy the stripe_cache is
4676 if (test_bit(R5_INACTIVE_BLOCKED
, &conf
->cache_state
))
4680 if (atomic_read(&conf
->empty_inactive_list_nr
))
4686 static int in_chunk_boundary(struct mddev
*mddev
, struct bio
*bio
)
4688 struct r5conf
*conf
= mddev
->private;
4689 sector_t sector
= bio
->bi_iter
.bi_sector
+ get_start_sect(bio
->bi_bdev
);
4690 unsigned int chunk_sectors
;
4691 unsigned int bio_sectors
= bio_sectors(bio
);
4693 chunk_sectors
= min(conf
->chunk_sectors
, conf
->prev_chunk_sectors
);
4694 return chunk_sectors
>=
4695 ((sector
& (chunk_sectors
- 1)) + bio_sectors
);
4699 * add bio to the retry LIFO ( in O(1) ... we are in interrupt )
4700 * later sampled by raid5d.
4702 static void add_bio_to_retry(struct bio
*bi
,struct r5conf
*conf
)
4704 unsigned long flags
;
4706 spin_lock_irqsave(&conf
->device_lock
, flags
);
4708 bi
->bi_next
= conf
->retry_read_aligned_list
;
4709 conf
->retry_read_aligned_list
= bi
;
4711 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
4712 md_wakeup_thread(conf
->mddev
->thread
);
4715 static struct bio
*remove_bio_from_retry(struct r5conf
*conf
)
4719 bi
= conf
->retry_read_aligned
;
4721 conf
->retry_read_aligned
= NULL
;
4724 bi
= conf
->retry_read_aligned_list
;
4726 conf
->retry_read_aligned_list
= bi
->bi_next
;
4729 * this sets the active strip count to 1 and the processed
4730 * strip count to zero (upper 8 bits)
4732 raid5_set_bi_stripes(bi
, 1); /* biased count of active stripes */
4739 * The "raid5_align_endio" should check if the read succeeded and if it
4740 * did, call bio_endio on the original bio (having bio_put the new bio
4742 * If the read failed..
4744 static void raid5_align_endio(struct bio
*bi
)
4746 struct bio
* raid_bi
= bi
->bi_private
;
4747 struct mddev
*mddev
;
4748 struct r5conf
*conf
;
4749 struct md_rdev
*rdev
;
4750 int error
= bi
->bi_error
;
4754 rdev
= (void*)raid_bi
->bi_next
;
4755 raid_bi
->bi_next
= NULL
;
4756 mddev
= rdev
->mddev
;
4757 conf
= mddev
->private;
4759 rdev_dec_pending(rdev
, conf
->mddev
);
4762 trace_block_bio_complete(bdev_get_queue(raid_bi
->bi_bdev
),
4765 if (atomic_dec_and_test(&conf
->active_aligned_reads
))
4766 wake_up(&conf
->wait_for_quiescent
);
4770 pr_debug("raid5_align_endio : io error...handing IO for a retry\n");
4772 add_bio_to_retry(raid_bi
, conf
);
4775 static int raid5_read_one_chunk(struct mddev
*mddev
, struct bio
*raid_bio
)
4777 struct r5conf
*conf
= mddev
->private;
4779 struct bio
* align_bi
;
4780 struct md_rdev
*rdev
;
4781 sector_t end_sector
;
4783 if (!in_chunk_boundary(mddev
, raid_bio
)) {
4784 pr_debug("%s: non aligned\n", __func__
);
4788 * use bio_clone_mddev to make a copy of the bio
4790 align_bi
= bio_clone_mddev(raid_bio
, GFP_NOIO
, mddev
);
4794 * set bi_end_io to a new function, and set bi_private to the
4797 align_bi
->bi_end_io
= raid5_align_endio
;
4798 align_bi
->bi_private
= raid_bio
;
4802 align_bi
->bi_iter
.bi_sector
=
4803 raid5_compute_sector(conf
, raid_bio
->bi_iter
.bi_sector
,
4806 end_sector
= bio_end_sector(align_bi
);
4808 rdev
= rcu_dereference(conf
->disks
[dd_idx
].replacement
);
4809 if (!rdev
|| test_bit(Faulty
, &rdev
->flags
) ||
4810 rdev
->recovery_offset
< end_sector
) {
4811 rdev
= rcu_dereference(conf
->disks
[dd_idx
].rdev
);
4813 (test_bit(Faulty
, &rdev
->flags
) ||
4814 !(test_bit(In_sync
, &rdev
->flags
) ||
4815 rdev
->recovery_offset
>= end_sector
)))
4822 atomic_inc(&rdev
->nr_pending
);
4824 raid_bio
->bi_next
= (void*)rdev
;
4825 align_bi
->bi_bdev
= rdev
->bdev
;
4826 bio_clear_flag(align_bi
, BIO_SEG_VALID
);
4828 if (is_badblock(rdev
, align_bi
->bi_iter
.bi_sector
,
4829 bio_sectors(align_bi
),
4830 &first_bad
, &bad_sectors
)) {
4832 rdev_dec_pending(rdev
, mddev
);
4836 /* No reshape active, so we can trust rdev->data_offset */
4837 align_bi
->bi_iter
.bi_sector
+= rdev
->data_offset
;
4839 spin_lock_irq(&conf
->device_lock
);
4840 wait_event_lock_irq(conf
->wait_for_quiescent
,
4843 atomic_inc(&conf
->active_aligned_reads
);
4844 spin_unlock_irq(&conf
->device_lock
);
4847 trace_block_bio_remap(bdev_get_queue(align_bi
->bi_bdev
),
4848 align_bi
, disk_devt(mddev
->gendisk
),
4849 raid_bio
->bi_iter
.bi_sector
);
4850 generic_make_request(align_bi
);
4859 static struct bio
*chunk_aligned_read(struct mddev
*mddev
, struct bio
*raid_bio
)
4864 sector_t sector
= raid_bio
->bi_iter
.bi_sector
;
4865 unsigned chunk_sects
= mddev
->chunk_sectors
;
4866 unsigned sectors
= chunk_sects
- (sector
& (chunk_sects
-1));
4868 if (sectors
< bio_sectors(raid_bio
)) {
4869 split
= bio_split(raid_bio
, sectors
, GFP_NOIO
, fs_bio_set
);
4870 bio_chain(split
, raid_bio
);
4874 if (!raid5_read_one_chunk(mddev
, split
)) {
4875 if (split
!= raid_bio
)
4876 generic_make_request(raid_bio
);
4879 } while (split
!= raid_bio
);
4884 /* __get_priority_stripe - get the next stripe to process
4886 * Full stripe writes are allowed to pass preread active stripes up until
4887 * the bypass_threshold is exceeded. In general the bypass_count
4888 * increments when the handle_list is handled before the hold_list; however, it
4889 * will not be incremented when STRIPE_IO_STARTED is sampled set signifying a
4890 * stripe with in flight i/o. The bypass_count will be reset when the
4891 * head of the hold_list has changed, i.e. the head was promoted to the
4894 static struct stripe_head
*__get_priority_stripe(struct r5conf
*conf
, int group
)
4896 struct stripe_head
*sh
= NULL
, *tmp
;
4897 struct list_head
*handle_list
= NULL
;
4898 struct r5worker_group
*wg
= NULL
;
4900 if (conf
->worker_cnt_per_group
== 0) {
4901 handle_list
= &conf
->handle_list
;
4902 } else if (group
!= ANY_GROUP
) {
4903 handle_list
= &conf
->worker_groups
[group
].handle_list
;
4904 wg
= &conf
->worker_groups
[group
];
4907 for (i
= 0; i
< conf
->group_cnt
; i
++) {
4908 handle_list
= &conf
->worker_groups
[i
].handle_list
;
4909 wg
= &conf
->worker_groups
[i
];
4910 if (!list_empty(handle_list
))
4915 pr_debug("%s: handle: %s hold: %s full_writes: %d bypass_count: %d\n",
4917 list_empty(handle_list
) ? "empty" : "busy",
4918 list_empty(&conf
->hold_list
) ? "empty" : "busy",
4919 atomic_read(&conf
->pending_full_writes
), conf
->bypass_count
);
4921 if (!list_empty(handle_list
)) {
4922 sh
= list_entry(handle_list
->next
, typeof(*sh
), lru
);
4924 if (list_empty(&conf
->hold_list
))
4925 conf
->bypass_count
= 0;
4926 else if (!test_bit(STRIPE_IO_STARTED
, &sh
->state
)) {
4927 if (conf
->hold_list
.next
== conf
->last_hold
)
4928 conf
->bypass_count
++;
4930 conf
->last_hold
= conf
->hold_list
.next
;
4931 conf
->bypass_count
-= conf
->bypass_threshold
;
4932 if (conf
->bypass_count
< 0)
4933 conf
->bypass_count
= 0;
4936 } else if (!list_empty(&conf
->hold_list
) &&
4937 ((conf
->bypass_threshold
&&
4938 conf
->bypass_count
> conf
->bypass_threshold
) ||
4939 atomic_read(&conf
->pending_full_writes
) == 0)) {
4941 list_for_each_entry(tmp
, &conf
->hold_list
, lru
) {
4942 if (conf
->worker_cnt_per_group
== 0 ||
4943 group
== ANY_GROUP
||
4944 !cpu_online(tmp
->cpu
) ||
4945 cpu_to_group(tmp
->cpu
) == group
) {
4952 conf
->bypass_count
-= conf
->bypass_threshold
;
4953 if (conf
->bypass_count
< 0)
4954 conf
->bypass_count
= 0;
4966 list_del_init(&sh
->lru
);
4967 BUG_ON(atomic_inc_return(&sh
->count
) != 1);
4971 struct raid5_plug_cb
{
4972 struct blk_plug_cb cb
;
4973 struct list_head list
;
4974 struct list_head temp_inactive_list
[NR_STRIPE_HASH_LOCKS
];
4977 static void raid5_unplug(struct blk_plug_cb
*blk_cb
, bool from_schedule
)
4979 struct raid5_plug_cb
*cb
= container_of(
4980 blk_cb
, struct raid5_plug_cb
, cb
);
4981 struct stripe_head
*sh
;
4982 struct mddev
*mddev
= cb
->cb
.data
;
4983 struct r5conf
*conf
= mddev
->private;
4987 if (cb
->list
.next
&& !list_empty(&cb
->list
)) {
4988 spin_lock_irq(&conf
->device_lock
);
4989 while (!list_empty(&cb
->list
)) {
4990 sh
= list_first_entry(&cb
->list
, struct stripe_head
, lru
);
4991 list_del_init(&sh
->lru
);
4993 * avoid race release_stripe_plug() sees
4994 * STRIPE_ON_UNPLUG_LIST clear but the stripe
4995 * is still in our list
4997 smp_mb__before_atomic();
4998 clear_bit(STRIPE_ON_UNPLUG_LIST
, &sh
->state
);
5000 * STRIPE_ON_RELEASE_LIST could be set here. In that
5001 * case, the count is always > 1 here
5003 hash
= sh
->hash_lock_index
;
5004 __release_stripe(conf
, sh
, &cb
->temp_inactive_list
[hash
]);
5007 spin_unlock_irq(&conf
->device_lock
);
5009 release_inactive_stripe_list(conf
, cb
->temp_inactive_list
,
5010 NR_STRIPE_HASH_LOCKS
);
5012 trace_block_unplug(mddev
->queue
, cnt
, !from_schedule
);
5016 static void release_stripe_plug(struct mddev
*mddev
,
5017 struct stripe_head
*sh
)
5019 struct blk_plug_cb
*blk_cb
= blk_check_plugged(
5020 raid5_unplug
, mddev
,
5021 sizeof(struct raid5_plug_cb
));
5022 struct raid5_plug_cb
*cb
;
5025 raid5_release_stripe(sh
);
5029 cb
= container_of(blk_cb
, struct raid5_plug_cb
, cb
);
5031 if (cb
->list
.next
== NULL
) {
5033 INIT_LIST_HEAD(&cb
->list
);
5034 for (i
= 0; i
< NR_STRIPE_HASH_LOCKS
; i
++)
5035 INIT_LIST_HEAD(cb
->temp_inactive_list
+ i
);
5038 if (!test_and_set_bit(STRIPE_ON_UNPLUG_LIST
, &sh
->state
))
5039 list_add_tail(&sh
->lru
, &cb
->list
);
5041 raid5_release_stripe(sh
);
5044 static void make_discard_request(struct mddev
*mddev
, struct bio
*bi
)
5046 struct r5conf
*conf
= mddev
->private;
5047 sector_t logical_sector
, last_sector
;
5048 struct stripe_head
*sh
;
5052 if (mddev
->reshape_position
!= MaxSector
)
5053 /* Skip discard while reshape is happening */
5056 logical_sector
= bi
->bi_iter
.bi_sector
& ~((sector_t
)STRIPE_SECTORS
-1);
5057 last_sector
= bi
->bi_iter
.bi_sector
+ (bi
->bi_iter
.bi_size
>>9);
5060 bi
->bi_phys_segments
= 1; /* over-loaded to count active stripes */
5062 stripe_sectors
= conf
->chunk_sectors
*
5063 (conf
->raid_disks
- conf
->max_degraded
);
5064 logical_sector
= DIV_ROUND_UP_SECTOR_T(logical_sector
,
5066 sector_div(last_sector
, stripe_sectors
);
5068 logical_sector
*= conf
->chunk_sectors
;
5069 last_sector
*= conf
->chunk_sectors
;
5071 for (; logical_sector
< last_sector
;
5072 logical_sector
+= STRIPE_SECTORS
) {
5076 sh
= raid5_get_active_stripe(conf
, logical_sector
, 0, 0, 0);
5077 prepare_to_wait(&conf
->wait_for_overlap
, &w
,
5078 TASK_UNINTERRUPTIBLE
);
5079 set_bit(R5_Overlap
, &sh
->dev
[sh
->pd_idx
].flags
);
5080 if (test_bit(STRIPE_SYNCING
, &sh
->state
)) {
5081 raid5_release_stripe(sh
);
5085 clear_bit(R5_Overlap
, &sh
->dev
[sh
->pd_idx
].flags
);
5086 spin_lock_irq(&sh
->stripe_lock
);
5087 for (d
= 0; d
< conf
->raid_disks
; d
++) {
5088 if (d
== sh
->pd_idx
|| d
== sh
->qd_idx
)
5090 if (sh
->dev
[d
].towrite
|| sh
->dev
[d
].toread
) {
5091 set_bit(R5_Overlap
, &sh
->dev
[d
].flags
);
5092 spin_unlock_irq(&sh
->stripe_lock
);
5093 raid5_release_stripe(sh
);
5098 set_bit(STRIPE_DISCARD
, &sh
->state
);
5099 finish_wait(&conf
->wait_for_overlap
, &w
);
5100 sh
->overwrite_disks
= 0;
5101 for (d
= 0; d
< conf
->raid_disks
; d
++) {
5102 if (d
== sh
->pd_idx
|| d
== sh
->qd_idx
)
5104 sh
->dev
[d
].towrite
= bi
;
5105 set_bit(R5_OVERWRITE
, &sh
->dev
[d
].flags
);
5106 raid5_inc_bi_active_stripes(bi
);
5107 sh
->overwrite_disks
++;
5109 spin_unlock_irq(&sh
->stripe_lock
);
5110 if (conf
->mddev
->bitmap
) {
5112 d
< conf
->raid_disks
- conf
->max_degraded
;
5114 bitmap_startwrite(mddev
->bitmap
,
5118 sh
->bm_seq
= conf
->seq_flush
+ 1;
5119 set_bit(STRIPE_BIT_DELAY
, &sh
->state
);
5122 set_bit(STRIPE_HANDLE
, &sh
->state
);
5123 clear_bit(STRIPE_DELAYED
, &sh
->state
);
5124 if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
5125 atomic_inc(&conf
->preread_active_stripes
);
5126 release_stripe_plug(mddev
, sh
);
5129 remaining
= raid5_dec_bi_active_stripes(bi
);
5130 if (remaining
== 0) {
5131 md_write_end(mddev
);
5136 static void make_request(struct mddev
*mddev
, struct bio
* bi
)
5138 struct r5conf
*conf
= mddev
->private;
5140 sector_t new_sector
;
5141 sector_t logical_sector
, last_sector
;
5142 struct stripe_head
*sh
;
5143 const int rw
= bio_data_dir(bi
);
5148 if (unlikely(bi
->bi_rw
& REQ_FLUSH
)) {
5149 md_flush_request(mddev
, bi
);
5153 md_write_start(mddev
, bi
);
5156 * If array is degraded, better not do chunk aligned read because
5157 * later we might have to read it again in order to reconstruct
5158 * data on failed drives.
5160 if (rw
== READ
&& mddev
->degraded
== 0 &&
5161 mddev
->reshape_position
== MaxSector
) {
5162 bi
= chunk_aligned_read(mddev
, bi
);
5167 if (unlikely(bi
->bi_rw
& REQ_DISCARD
)) {
5168 make_discard_request(mddev
, bi
);
5172 logical_sector
= bi
->bi_iter
.bi_sector
& ~((sector_t
)STRIPE_SECTORS
-1);
5173 last_sector
= bio_end_sector(bi
);
5175 bi
->bi_phys_segments
= 1; /* over-loaded to count active stripes */
5177 prepare_to_wait(&conf
->wait_for_overlap
, &w
, TASK_UNINTERRUPTIBLE
);
5178 for (;logical_sector
< last_sector
; logical_sector
+= STRIPE_SECTORS
) {
5184 seq
= read_seqcount_begin(&conf
->gen_lock
);
5187 prepare_to_wait(&conf
->wait_for_overlap
, &w
,
5188 TASK_UNINTERRUPTIBLE
);
5189 if (unlikely(conf
->reshape_progress
!= MaxSector
)) {
5190 /* spinlock is needed as reshape_progress may be
5191 * 64bit on a 32bit platform, and so it might be
5192 * possible to see a half-updated value
5193 * Of course reshape_progress could change after
5194 * the lock is dropped, so once we get a reference
5195 * to the stripe that we think it is, we will have
5198 spin_lock_irq(&conf
->device_lock
);
5199 if (mddev
->reshape_backwards
5200 ? logical_sector
< conf
->reshape_progress
5201 : logical_sector
>= conf
->reshape_progress
) {
5204 if (mddev
->reshape_backwards
5205 ? logical_sector
< conf
->reshape_safe
5206 : logical_sector
>= conf
->reshape_safe
) {
5207 spin_unlock_irq(&conf
->device_lock
);
5213 spin_unlock_irq(&conf
->device_lock
);
5216 new_sector
= raid5_compute_sector(conf
, logical_sector
,
5219 pr_debug("raid456: make_request, sector %llu logical %llu\n",
5220 (unsigned long long)new_sector
,
5221 (unsigned long long)logical_sector
);
5223 sh
= raid5_get_active_stripe(conf
, new_sector
, previous
,
5224 (bi
->bi_rw
&RWA_MASK
), 0);
5226 if (unlikely(previous
)) {
5227 /* expansion might have moved on while waiting for a
5228 * stripe, so we must do the range check again.
5229 * Expansion could still move past after this
5230 * test, but as we are holding a reference to
5231 * 'sh', we know that if that happens,
5232 * STRIPE_EXPANDING will get set and the expansion
5233 * won't proceed until we finish with the stripe.
5236 spin_lock_irq(&conf
->device_lock
);
5237 if (mddev
->reshape_backwards
5238 ? logical_sector
>= conf
->reshape_progress
5239 : logical_sector
< conf
->reshape_progress
)
5240 /* mismatch, need to try again */
5242 spin_unlock_irq(&conf
->device_lock
);
5244 raid5_release_stripe(sh
);
5250 if (read_seqcount_retry(&conf
->gen_lock
, seq
)) {
5251 /* Might have got the wrong stripe_head
5254 raid5_release_stripe(sh
);
5259 logical_sector
>= mddev
->suspend_lo
&&
5260 logical_sector
< mddev
->suspend_hi
) {
5261 raid5_release_stripe(sh
);
5262 /* As the suspend_* range is controlled by
5263 * userspace, we want an interruptible
5266 flush_signals(current
);
5267 prepare_to_wait(&conf
->wait_for_overlap
,
5268 &w
, TASK_INTERRUPTIBLE
);
5269 if (logical_sector
>= mddev
->suspend_lo
&&
5270 logical_sector
< mddev
->suspend_hi
) {
5277 if (test_bit(STRIPE_EXPANDING
, &sh
->state
) ||
5278 !add_stripe_bio(sh
, bi
, dd_idx
, rw
, previous
)) {
5279 /* Stripe is busy expanding or
5280 * add failed due to overlap. Flush everything
5283 md_wakeup_thread(mddev
->thread
);
5284 raid5_release_stripe(sh
);
5289 set_bit(STRIPE_HANDLE
, &sh
->state
);
5290 clear_bit(STRIPE_DELAYED
, &sh
->state
);
5291 if ((!sh
->batch_head
|| sh
== sh
->batch_head
) &&
5292 (bi
->bi_rw
& REQ_SYNC
) &&
5293 !test_and_set_bit(STRIPE_PREREAD_ACTIVE
, &sh
->state
))
5294 atomic_inc(&conf
->preread_active_stripes
);
5295 release_stripe_plug(mddev
, sh
);
5297 /* cannot get stripe for read-ahead, just give-up */
5298 bi
->bi_error
= -EIO
;
5302 finish_wait(&conf
->wait_for_overlap
, &w
);
5304 remaining
= raid5_dec_bi_active_stripes(bi
);
5305 if (remaining
== 0) {
5308 md_write_end(mddev
);
5310 trace_block_bio_complete(bdev_get_queue(bi
->bi_bdev
),
5316 static sector_t
raid5_size(struct mddev
*mddev
, sector_t sectors
, int raid_disks
);
5318 static sector_t
reshape_request(struct mddev
*mddev
, sector_t sector_nr
, int *skipped
)
5320 /* reshaping is quite different to recovery/resync so it is
5321 * handled quite separately ... here.
5323 * On each call to sync_request, we gather one chunk worth of
5324 * destination stripes and flag them as expanding.
5325 * Then we find all the source stripes and request reads.
5326 * As the reads complete, handle_stripe will copy the data
5327 * into the destination stripe and release that stripe.
5329 struct r5conf
*conf
= mddev
->private;
5330 struct stripe_head
*sh
;
5331 sector_t first_sector
, last_sector
;
5332 int raid_disks
= conf
->previous_raid_disks
;
5333 int data_disks
= raid_disks
- conf
->max_degraded
;
5334 int new_data_disks
= conf
->raid_disks
- conf
->max_degraded
;
5337 sector_t writepos
, readpos
, safepos
;
5338 sector_t stripe_addr
;
5339 int reshape_sectors
;
5340 struct list_head stripes
;
5343 if (sector_nr
== 0) {
5344 /* If restarting in the middle, skip the initial sectors */
5345 if (mddev
->reshape_backwards
&&
5346 conf
->reshape_progress
< raid5_size(mddev
, 0, 0)) {
5347 sector_nr
= raid5_size(mddev
, 0, 0)
5348 - conf
->reshape_progress
;
5349 } else if (mddev
->reshape_backwards
&&
5350 conf
->reshape_progress
== MaxSector
) {
5351 /* shouldn't happen, but just in case, finish up.*/
5352 sector_nr
= MaxSector
;
5353 } else if (!mddev
->reshape_backwards
&&
5354 conf
->reshape_progress
> 0)
5355 sector_nr
= conf
->reshape_progress
;
5356 sector_div(sector_nr
, new_data_disks
);
5358 mddev
->curr_resync_completed
= sector_nr
;
5359 sysfs_notify(&mddev
->kobj
, NULL
, "sync_completed");
5366 /* We need to process a full chunk at a time.
5367 * If old and new chunk sizes differ, we need to process the
5371 reshape_sectors
= max(conf
->chunk_sectors
, conf
->prev_chunk_sectors
);
5373 /* We update the metadata at least every 10 seconds, or when
5374 * the data about to be copied would over-write the source of
5375 * the data at the front of the range. i.e. one new_stripe
5376 * along from reshape_progress new_maps to after where
5377 * reshape_safe old_maps to
5379 writepos
= conf
->reshape_progress
;
5380 sector_div(writepos
, new_data_disks
);
5381 readpos
= conf
->reshape_progress
;
5382 sector_div(readpos
, data_disks
);
5383 safepos
= conf
->reshape_safe
;
5384 sector_div(safepos
, data_disks
);
5385 if (mddev
->reshape_backwards
) {
5386 BUG_ON(writepos
< reshape_sectors
);
5387 writepos
-= reshape_sectors
;
5388 readpos
+= reshape_sectors
;
5389 safepos
+= reshape_sectors
;
5391 writepos
+= reshape_sectors
;
5392 /* readpos and safepos are worst-case calculations.
5393 * A negative number is overly pessimistic, and causes
5394 * obvious problems for unsigned storage. So clip to 0.
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
= raid5_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
= raid5_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
= raid5_get_active_stripe(conf
, first_sector
, 1, 0, 1);
5521 set_bit(STRIPE_EXPAND_SOURCE
, &sh
->state
);
5522 set_bit(STRIPE_HANDLE
, &sh
->state
);
5523 raid5_release_stripe(sh
);
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
);
5532 raid5_release_stripe(sh
);
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 retn
= reshape_sectors
;
5540 if (mddev
->curr_resync_completed
> mddev
->resync_max
||
5541 (sector_nr
- mddev
->curr_resync_completed
) * 2
5542 >= mddev
->resync_max
- mddev
->curr_resync_completed
) {
5543 /* Cannot proceed until we've updated the superblock... */
5544 wait_event(conf
->wait_for_overlap
,
5545 atomic_read(&conf
->reshape_stripes
) == 0
5546 || test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
));
5547 if (atomic_read(&conf
->reshape_stripes
) != 0)
5549 mddev
->reshape_position
= conf
->reshape_progress
;
5550 mddev
->curr_resync_completed
= sector_nr
;
5551 conf
->reshape_checkpoint
= jiffies
;
5552 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
5553 md_wakeup_thread(mddev
->thread
);
5554 wait_event(mddev
->sb_wait
,
5555 !test_bit(MD_CHANGE_DEVS
, &mddev
->flags
)
5556 || test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
));
5557 if (test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
))
5559 spin_lock_irq(&conf
->device_lock
);
5560 conf
->reshape_safe
= mddev
->reshape_position
;
5561 spin_unlock_irq(&conf
->device_lock
);
5562 wake_up(&conf
->wait_for_overlap
);
5563 sysfs_notify(&mddev
->kobj
, NULL
, "sync_completed");
5569 static inline sector_t
sync_request(struct mddev
*mddev
, sector_t sector_nr
, int *skipped
)
5571 struct r5conf
*conf
= mddev
->private;
5572 struct stripe_head
*sh
;
5573 sector_t max_sector
= mddev
->dev_sectors
;
5574 sector_t sync_blocks
;
5575 int still_degraded
= 0;
5578 if (sector_nr
>= max_sector
) {
5579 /* just being told to finish up .. nothing much to do */
5581 if (test_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
)) {
5586 if (mddev
->curr_resync
< max_sector
) /* aborted */
5587 bitmap_end_sync(mddev
->bitmap
, mddev
->curr_resync
,
5589 else /* completed sync */
5591 bitmap_close_sync(mddev
->bitmap
);
5596 /* Allow raid5_quiesce to complete */
5597 wait_event(conf
->wait_for_overlap
, conf
->quiesce
!= 2);
5599 if (test_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
))
5600 return reshape_request(mddev
, sector_nr
, skipped
);
5602 /* No need to check resync_max as we never do more than one
5603 * stripe, and as resync_max will always be on a chunk boundary,
5604 * if the check in md_do_sync didn't fire, there is no chance
5605 * of overstepping resync_max here
5608 /* if there is too many failed drives and we are trying
5609 * to resync, then assert that we are finished, because there is
5610 * nothing we can do.
5612 if (mddev
->degraded
>= conf
->max_degraded
&&
5613 test_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
)) {
5614 sector_t rv
= mddev
->dev_sectors
- sector_nr
;
5618 if (!test_bit(MD_RECOVERY_REQUESTED
, &mddev
->recovery
) &&
5620 !bitmap_start_sync(mddev
->bitmap
, sector_nr
, &sync_blocks
, 1) &&
5621 sync_blocks
>= STRIPE_SECTORS
) {
5622 /* we can skip this block, and probably more */
5623 sync_blocks
/= STRIPE_SECTORS
;
5625 return sync_blocks
* STRIPE_SECTORS
; /* keep things rounded to whole stripes */
5628 bitmap_cond_end_sync(mddev
->bitmap
, sector_nr
, false);
5630 sh
= raid5_get_active_stripe(conf
, sector_nr
, 0, 1, 0);
5632 sh
= raid5_get_active_stripe(conf
, sector_nr
, 0, 0, 0);
5633 /* make sure we don't swamp the stripe cache if someone else
5634 * is trying to get access
5636 schedule_timeout_uninterruptible(1);
5638 /* Need to check if array will still be degraded after recovery/resync
5639 * Note in case of > 1 drive failures it's possible we're rebuilding
5640 * one drive while leaving another faulty drive in array.
5643 for (i
= 0; i
< conf
->raid_disks
; i
++) {
5644 struct md_rdev
*rdev
= ACCESS_ONCE(conf
->disks
[i
].rdev
);
5646 if (rdev
== NULL
|| test_bit(Faulty
, &rdev
->flags
))
5651 bitmap_start_sync(mddev
->bitmap
, sector_nr
, &sync_blocks
, still_degraded
);
5653 set_bit(STRIPE_SYNC_REQUESTED
, &sh
->state
);
5654 set_bit(STRIPE_HANDLE
, &sh
->state
);
5656 raid5_release_stripe(sh
);
5658 return STRIPE_SECTORS
;
5661 static int retry_aligned_read(struct r5conf
*conf
, struct bio
*raid_bio
)
5663 /* We may not be able to submit a whole bio at once as there
5664 * may not be enough stripe_heads available.
5665 * We cannot pre-allocate enough stripe_heads as we may need
5666 * more than exist in the cache (if we allow ever large chunks).
5667 * So we do one stripe head at a time and record in
5668 * ->bi_hw_segments how many have been done.
5670 * We *know* that this entire raid_bio is in one chunk, so
5671 * it will be only one 'dd_idx' and only need one call to raid5_compute_sector.
5673 struct stripe_head
*sh
;
5675 sector_t sector
, logical_sector
, last_sector
;
5680 logical_sector
= raid_bio
->bi_iter
.bi_sector
&
5681 ~((sector_t
)STRIPE_SECTORS
-1);
5682 sector
= raid5_compute_sector(conf
, logical_sector
,
5684 last_sector
= bio_end_sector(raid_bio
);
5686 for (; logical_sector
< last_sector
;
5687 logical_sector
+= STRIPE_SECTORS
,
5688 sector
+= STRIPE_SECTORS
,
5691 if (scnt
< raid5_bi_processed_stripes(raid_bio
))
5692 /* already done this stripe */
5695 sh
= raid5_get_active_stripe(conf
, sector
, 0, 1, 1);
5698 /* failed to get a stripe - must wait */
5699 raid5_set_bi_processed_stripes(raid_bio
, scnt
);
5700 conf
->retry_read_aligned
= raid_bio
;
5704 if (!add_stripe_bio(sh
, raid_bio
, dd_idx
, 0, 0)) {
5705 raid5_release_stripe(sh
);
5706 raid5_set_bi_processed_stripes(raid_bio
, scnt
);
5707 conf
->retry_read_aligned
= raid_bio
;
5711 set_bit(R5_ReadNoMerge
, &sh
->dev
[dd_idx
].flags
);
5713 raid5_release_stripe(sh
);
5716 remaining
= raid5_dec_bi_active_stripes(raid_bio
);
5717 if (remaining
== 0) {
5718 trace_block_bio_complete(bdev_get_queue(raid_bio
->bi_bdev
),
5720 bio_endio(raid_bio
);
5722 if (atomic_dec_and_test(&conf
->active_aligned_reads
))
5723 wake_up(&conf
->wait_for_quiescent
);
5727 static int handle_active_stripes(struct r5conf
*conf
, int group
,
5728 struct r5worker
*worker
,
5729 struct list_head
*temp_inactive_list
)
5731 struct stripe_head
*batch
[MAX_STRIPE_BATCH
], *sh
;
5732 int i
, batch_size
= 0, hash
;
5733 bool release_inactive
= false;
5735 while (batch_size
< MAX_STRIPE_BATCH
&&
5736 (sh
= __get_priority_stripe(conf
, group
)) != NULL
)
5737 batch
[batch_size
++] = sh
;
5739 if (batch_size
== 0) {
5740 for (i
= 0; i
< NR_STRIPE_HASH_LOCKS
; i
++)
5741 if (!list_empty(temp_inactive_list
+ i
))
5743 if (i
== NR_STRIPE_HASH_LOCKS
)
5745 release_inactive
= true;
5747 spin_unlock_irq(&conf
->device_lock
);
5749 release_inactive_stripe_list(conf
, temp_inactive_list
,
5750 NR_STRIPE_HASH_LOCKS
);
5752 if (release_inactive
) {
5753 spin_lock_irq(&conf
->device_lock
);
5757 for (i
= 0; i
< batch_size
; i
++)
5758 handle_stripe(batch
[i
]);
5759 r5l_write_stripe_run(conf
->log
);
5763 spin_lock_irq(&conf
->device_lock
);
5764 for (i
= 0; i
< batch_size
; i
++) {
5765 hash
= batch
[i
]->hash_lock_index
;
5766 __release_stripe(conf
, batch
[i
], &temp_inactive_list
[hash
]);
5771 static void raid5_do_work(struct work_struct
*work
)
5773 struct r5worker
*worker
= container_of(work
, struct r5worker
, work
);
5774 struct r5worker_group
*group
= worker
->group
;
5775 struct r5conf
*conf
= group
->conf
;
5776 int group_id
= group
- conf
->worker_groups
;
5778 struct blk_plug plug
;
5780 pr_debug("+++ raid5worker active\n");
5782 blk_start_plug(&plug
);
5784 spin_lock_irq(&conf
->device_lock
);
5786 int batch_size
, released
;
5788 released
= release_stripe_list(conf
, worker
->temp_inactive_list
);
5790 batch_size
= handle_active_stripes(conf
, group_id
, worker
,
5791 worker
->temp_inactive_list
);
5792 worker
->working
= false;
5793 if (!batch_size
&& !released
)
5795 handled
+= batch_size
;
5797 pr_debug("%d stripes handled\n", handled
);
5799 spin_unlock_irq(&conf
->device_lock
);
5800 blk_finish_plug(&plug
);
5802 pr_debug("--- raid5worker inactive\n");
5806 * This is our raid5 kernel thread.
5808 * We scan the hash table for stripes which can be handled now.
5809 * During the scan, completed stripes are saved for us by the interrupt
5810 * handler, so that they will not have to wait for our next wakeup.
5812 static void raid5d(struct md_thread
*thread
)
5814 struct mddev
*mddev
= thread
->mddev
;
5815 struct r5conf
*conf
= mddev
->private;
5817 struct blk_plug plug
;
5819 pr_debug("+++ raid5d active\n");
5821 md_check_recovery(mddev
);
5823 if (!bio_list_empty(&conf
->return_bi
) &&
5824 !test_bit(MD_CHANGE_PENDING
, &mddev
->flags
)) {
5825 struct bio_list tmp
= BIO_EMPTY_LIST
;
5826 spin_lock_irq(&conf
->device_lock
);
5827 if (!test_bit(MD_CHANGE_PENDING
, &mddev
->flags
)) {
5828 bio_list_merge(&tmp
, &conf
->return_bi
);
5829 bio_list_init(&conf
->return_bi
);
5831 spin_unlock_irq(&conf
->device_lock
);
5835 blk_start_plug(&plug
);
5837 spin_lock_irq(&conf
->device_lock
);
5840 int batch_size
, released
;
5842 released
= release_stripe_list(conf
, conf
->temp_inactive_list
);
5844 clear_bit(R5_DID_ALLOC
, &conf
->cache_state
);
5847 !list_empty(&conf
->bitmap_list
)) {
5848 /* Now is a good time to flush some bitmap updates */
5850 spin_unlock_irq(&conf
->device_lock
);
5851 bitmap_unplug(mddev
->bitmap
);
5852 spin_lock_irq(&conf
->device_lock
);
5853 conf
->seq_write
= conf
->seq_flush
;
5854 activate_bit_delay(conf
, conf
->temp_inactive_list
);
5856 raid5_activate_delayed(conf
);
5858 while ((bio
= remove_bio_from_retry(conf
))) {
5860 spin_unlock_irq(&conf
->device_lock
);
5861 ok
= retry_aligned_read(conf
, bio
);
5862 spin_lock_irq(&conf
->device_lock
);
5868 batch_size
= handle_active_stripes(conf
, ANY_GROUP
, NULL
,
5869 conf
->temp_inactive_list
);
5870 if (!batch_size
&& !released
)
5872 handled
+= batch_size
;
5874 if (mddev
->flags
& ~(1<<MD_CHANGE_PENDING
)) {
5875 spin_unlock_irq(&conf
->device_lock
);
5876 md_check_recovery(mddev
);
5877 spin_lock_irq(&conf
->device_lock
);
5880 pr_debug("%d stripes handled\n", handled
);
5882 spin_unlock_irq(&conf
->device_lock
);
5883 if (test_and_clear_bit(R5_ALLOC_MORE
, &conf
->cache_state
) &&
5884 mutex_trylock(&conf
->cache_size_mutex
)) {
5885 grow_one_stripe(conf
, __GFP_NOWARN
);
5886 /* Set flag even if allocation failed. This helps
5887 * slow down allocation requests when mem is short
5889 set_bit(R5_DID_ALLOC
, &conf
->cache_state
);
5890 mutex_unlock(&conf
->cache_size_mutex
);
5893 r5l_flush_stripe_to_raid(conf
->log
);
5895 async_tx_issue_pending_all();
5896 blk_finish_plug(&plug
);
5898 pr_debug("--- raid5d inactive\n");
5902 raid5_show_stripe_cache_size(struct mddev
*mddev
, char *page
)
5904 struct r5conf
*conf
;
5906 spin_lock(&mddev
->lock
);
5907 conf
= mddev
->private;
5909 ret
= sprintf(page
, "%d\n", conf
->min_nr_stripes
);
5910 spin_unlock(&mddev
->lock
);
5915 raid5_set_cache_size(struct mddev
*mddev
, int size
)
5917 struct r5conf
*conf
= mddev
->private;
5920 if (size
<= 16 || size
> 32768)
5923 conf
->min_nr_stripes
= size
;
5924 mutex_lock(&conf
->cache_size_mutex
);
5925 while (size
< conf
->max_nr_stripes
&&
5926 drop_one_stripe(conf
))
5928 mutex_unlock(&conf
->cache_size_mutex
);
5931 err
= md_allow_write(mddev
);
5935 mutex_lock(&conf
->cache_size_mutex
);
5936 while (size
> conf
->max_nr_stripes
)
5937 if (!grow_one_stripe(conf
, GFP_KERNEL
))
5939 mutex_unlock(&conf
->cache_size_mutex
);
5943 EXPORT_SYMBOL(raid5_set_cache_size
);
5946 raid5_store_stripe_cache_size(struct mddev
*mddev
, const char *page
, size_t len
)
5948 struct r5conf
*conf
;
5952 if (len
>= PAGE_SIZE
)
5954 if (kstrtoul(page
, 10, &new))
5956 err
= mddev_lock(mddev
);
5959 conf
= mddev
->private;
5963 err
= raid5_set_cache_size(mddev
, new);
5964 mddev_unlock(mddev
);
5969 static struct md_sysfs_entry
5970 raid5_stripecache_size
= __ATTR(stripe_cache_size
, S_IRUGO
| S_IWUSR
,
5971 raid5_show_stripe_cache_size
,
5972 raid5_store_stripe_cache_size
);
5975 raid5_show_rmw_level(struct mddev
*mddev
, char *page
)
5977 struct r5conf
*conf
= mddev
->private;
5979 return sprintf(page
, "%d\n", conf
->rmw_level
);
5985 raid5_store_rmw_level(struct mddev
*mddev
, const char *page
, size_t len
)
5987 struct r5conf
*conf
= mddev
->private;
5993 if (len
>= PAGE_SIZE
)
5996 if (kstrtoul(page
, 10, &new))
5999 if (new != PARITY_DISABLE_RMW
&& !raid6_call
.xor_syndrome
)
6002 if (new != PARITY_DISABLE_RMW
&&
6003 new != PARITY_ENABLE_RMW
&&
6004 new != PARITY_PREFER_RMW
)
6007 conf
->rmw_level
= new;
6011 static struct md_sysfs_entry
6012 raid5_rmw_level
= __ATTR(rmw_level
, S_IRUGO
| S_IWUSR
,
6013 raid5_show_rmw_level
,
6014 raid5_store_rmw_level
);
6018 raid5_show_preread_threshold(struct mddev
*mddev
, char *page
)
6020 struct r5conf
*conf
;
6022 spin_lock(&mddev
->lock
);
6023 conf
= mddev
->private;
6025 ret
= sprintf(page
, "%d\n", conf
->bypass_threshold
);
6026 spin_unlock(&mddev
->lock
);
6031 raid5_store_preread_threshold(struct mddev
*mddev
, const char *page
, size_t len
)
6033 struct r5conf
*conf
;
6037 if (len
>= PAGE_SIZE
)
6039 if (kstrtoul(page
, 10, &new))
6042 err
= mddev_lock(mddev
);
6045 conf
= mddev
->private;
6048 else if (new > conf
->min_nr_stripes
)
6051 conf
->bypass_threshold
= new;
6052 mddev_unlock(mddev
);
6056 static struct md_sysfs_entry
6057 raid5_preread_bypass_threshold
= __ATTR(preread_bypass_threshold
,
6059 raid5_show_preread_threshold
,
6060 raid5_store_preread_threshold
);
6063 raid5_show_skip_copy(struct mddev
*mddev
, char *page
)
6065 struct r5conf
*conf
;
6067 spin_lock(&mddev
->lock
);
6068 conf
= mddev
->private;
6070 ret
= sprintf(page
, "%d\n", conf
->skip_copy
);
6071 spin_unlock(&mddev
->lock
);
6076 raid5_store_skip_copy(struct mddev
*mddev
, const char *page
, size_t len
)
6078 struct r5conf
*conf
;
6082 if (len
>= PAGE_SIZE
)
6084 if (kstrtoul(page
, 10, &new))
6088 err
= mddev_lock(mddev
);
6091 conf
= mddev
->private;
6094 else if (new != conf
->skip_copy
) {
6095 mddev_suspend(mddev
);
6096 conf
->skip_copy
= new;
6098 mddev
->queue
->backing_dev_info
.capabilities
|=
6099 BDI_CAP_STABLE_WRITES
;
6101 mddev
->queue
->backing_dev_info
.capabilities
&=
6102 ~BDI_CAP_STABLE_WRITES
;
6103 mddev_resume(mddev
);
6105 mddev_unlock(mddev
);
6109 static struct md_sysfs_entry
6110 raid5_skip_copy
= __ATTR(skip_copy
, S_IRUGO
| S_IWUSR
,
6111 raid5_show_skip_copy
,
6112 raid5_store_skip_copy
);
6115 stripe_cache_active_show(struct mddev
*mddev
, char *page
)
6117 struct r5conf
*conf
= mddev
->private;
6119 return sprintf(page
, "%d\n", atomic_read(&conf
->active_stripes
));
6124 static struct md_sysfs_entry
6125 raid5_stripecache_active
= __ATTR_RO(stripe_cache_active
);
6128 raid5_show_group_thread_cnt(struct mddev
*mddev
, char *page
)
6130 struct r5conf
*conf
;
6132 spin_lock(&mddev
->lock
);
6133 conf
= mddev
->private;
6135 ret
= sprintf(page
, "%d\n", conf
->worker_cnt_per_group
);
6136 spin_unlock(&mddev
->lock
);
6140 static int alloc_thread_groups(struct r5conf
*conf
, int cnt
,
6142 int *worker_cnt_per_group
,
6143 struct r5worker_group
**worker_groups
);
6145 raid5_store_group_thread_cnt(struct mddev
*mddev
, const char *page
, size_t len
)
6147 struct r5conf
*conf
;
6150 struct r5worker_group
*new_groups
, *old_groups
;
6151 int group_cnt
, worker_cnt_per_group
;
6153 if (len
>= PAGE_SIZE
)
6155 if (kstrtoul(page
, 10, &new))
6158 err
= mddev_lock(mddev
);
6161 conf
= mddev
->private;
6164 else if (new != conf
->worker_cnt_per_group
) {
6165 mddev_suspend(mddev
);
6167 old_groups
= conf
->worker_groups
;
6169 flush_workqueue(raid5_wq
);
6171 err
= alloc_thread_groups(conf
, new,
6172 &group_cnt
, &worker_cnt_per_group
,
6175 spin_lock_irq(&conf
->device_lock
);
6176 conf
->group_cnt
= group_cnt
;
6177 conf
->worker_cnt_per_group
= worker_cnt_per_group
;
6178 conf
->worker_groups
= new_groups
;
6179 spin_unlock_irq(&conf
->device_lock
);
6182 kfree(old_groups
[0].workers
);
6185 mddev_resume(mddev
);
6187 mddev_unlock(mddev
);
6192 static struct md_sysfs_entry
6193 raid5_group_thread_cnt
= __ATTR(group_thread_cnt
, S_IRUGO
| S_IWUSR
,
6194 raid5_show_group_thread_cnt
,
6195 raid5_store_group_thread_cnt
);
6197 static struct attribute
*raid5_attrs
[] = {
6198 &raid5_stripecache_size
.attr
,
6199 &raid5_stripecache_active
.attr
,
6200 &raid5_preread_bypass_threshold
.attr
,
6201 &raid5_group_thread_cnt
.attr
,
6202 &raid5_skip_copy
.attr
,
6203 &raid5_rmw_level
.attr
,
6206 static struct attribute_group raid5_attrs_group
= {
6208 .attrs
= raid5_attrs
,
6211 static int alloc_thread_groups(struct r5conf
*conf
, int cnt
,
6213 int *worker_cnt_per_group
,
6214 struct r5worker_group
**worker_groups
)
6218 struct r5worker
*workers
;
6220 *worker_cnt_per_group
= cnt
;
6223 *worker_groups
= NULL
;
6226 *group_cnt
= num_possible_nodes();
6227 size
= sizeof(struct r5worker
) * cnt
;
6228 workers
= kzalloc(size
* *group_cnt
, GFP_NOIO
);
6229 *worker_groups
= kzalloc(sizeof(struct r5worker_group
) *
6230 *group_cnt
, GFP_NOIO
);
6231 if (!*worker_groups
|| !workers
) {
6233 kfree(*worker_groups
);
6237 for (i
= 0; i
< *group_cnt
; i
++) {
6238 struct r5worker_group
*group
;
6240 group
= &(*worker_groups
)[i
];
6241 INIT_LIST_HEAD(&group
->handle_list
);
6243 group
->workers
= workers
+ i
* cnt
;
6245 for (j
= 0; j
< cnt
; j
++) {
6246 struct r5worker
*worker
= group
->workers
+ j
;
6247 worker
->group
= group
;
6248 INIT_WORK(&worker
->work
, raid5_do_work
);
6250 for (k
= 0; k
< NR_STRIPE_HASH_LOCKS
; k
++)
6251 INIT_LIST_HEAD(worker
->temp_inactive_list
+ k
);
6258 static void free_thread_groups(struct r5conf
*conf
)
6260 if (conf
->worker_groups
)
6261 kfree(conf
->worker_groups
[0].workers
);
6262 kfree(conf
->worker_groups
);
6263 conf
->worker_groups
= NULL
;
6267 raid5_size(struct mddev
*mddev
, sector_t sectors
, int raid_disks
)
6269 struct r5conf
*conf
= mddev
->private;
6272 sectors
= mddev
->dev_sectors
;
6274 /* size is defined by the smallest of previous and new size */
6275 raid_disks
= min(conf
->raid_disks
, conf
->previous_raid_disks
);
6277 sectors
&= ~((sector_t
)conf
->chunk_sectors
- 1);
6278 sectors
&= ~((sector_t
)conf
->prev_chunk_sectors
- 1);
6279 return sectors
* (raid_disks
- conf
->max_degraded
);
6282 static void free_scratch_buffer(struct r5conf
*conf
, struct raid5_percpu
*percpu
)
6284 safe_put_page(percpu
->spare_page
);
6285 if (percpu
->scribble
)
6286 flex_array_free(percpu
->scribble
);
6287 percpu
->spare_page
= NULL
;
6288 percpu
->scribble
= NULL
;
6291 static int alloc_scratch_buffer(struct r5conf
*conf
, struct raid5_percpu
*percpu
)
6293 if (conf
->level
== 6 && !percpu
->spare_page
)
6294 percpu
->spare_page
= alloc_page(GFP_KERNEL
);
6295 if (!percpu
->scribble
)
6296 percpu
->scribble
= scribble_alloc(max(conf
->raid_disks
,
6297 conf
->previous_raid_disks
),
6298 max(conf
->chunk_sectors
,
6299 conf
->prev_chunk_sectors
)
6303 if (!percpu
->scribble
|| (conf
->level
== 6 && !percpu
->spare_page
)) {
6304 free_scratch_buffer(conf
, percpu
);
6311 static void raid5_free_percpu(struct r5conf
*conf
)
6318 #ifdef CONFIG_HOTPLUG_CPU
6319 unregister_cpu_notifier(&conf
->cpu_notify
);
6323 for_each_possible_cpu(cpu
)
6324 free_scratch_buffer(conf
, per_cpu_ptr(conf
->percpu
, cpu
));
6327 free_percpu(conf
->percpu
);
6330 static void free_conf(struct r5conf
*conf
)
6332 if (conf
->shrinker
.seeks
)
6333 unregister_shrinker(&conf
->shrinker
);
6334 free_thread_groups(conf
);
6335 shrink_stripes(conf
);
6336 raid5_free_percpu(conf
);
6338 kfree(conf
->stripe_hashtbl
);
6342 #ifdef CONFIG_HOTPLUG_CPU
6343 static int raid456_cpu_notify(struct notifier_block
*nfb
, unsigned long action
,
6346 struct r5conf
*conf
= container_of(nfb
, struct r5conf
, cpu_notify
);
6347 long cpu
= (long)hcpu
;
6348 struct raid5_percpu
*percpu
= per_cpu_ptr(conf
->percpu
, cpu
);
6351 case CPU_UP_PREPARE
:
6352 case CPU_UP_PREPARE_FROZEN
:
6353 if (alloc_scratch_buffer(conf
, percpu
)) {
6354 pr_err("%s: failed memory allocation for cpu%ld\n",
6356 return notifier_from_errno(-ENOMEM
);
6360 case CPU_DEAD_FROZEN
:
6361 free_scratch_buffer(conf
, per_cpu_ptr(conf
->percpu
, cpu
));
6370 static int raid5_alloc_percpu(struct r5conf
*conf
)
6375 conf
->percpu
= alloc_percpu(struct raid5_percpu
);
6379 #ifdef CONFIG_HOTPLUG_CPU
6380 conf
->cpu_notify
.notifier_call
= raid456_cpu_notify
;
6381 conf
->cpu_notify
.priority
= 0;
6382 err
= register_cpu_notifier(&conf
->cpu_notify
);
6388 for_each_present_cpu(cpu
) {
6389 err
= alloc_scratch_buffer(conf
, per_cpu_ptr(conf
->percpu
, cpu
));
6391 pr_err("%s: failed memory allocation for cpu%ld\n",
6401 static unsigned long raid5_cache_scan(struct shrinker
*shrink
,
6402 struct shrink_control
*sc
)
6404 struct r5conf
*conf
= container_of(shrink
, struct r5conf
, shrinker
);
6405 unsigned long ret
= SHRINK_STOP
;
6407 if (mutex_trylock(&conf
->cache_size_mutex
)) {
6409 while (ret
< sc
->nr_to_scan
&&
6410 conf
->max_nr_stripes
> conf
->min_nr_stripes
) {
6411 if (drop_one_stripe(conf
) == 0) {
6417 mutex_unlock(&conf
->cache_size_mutex
);
6422 static unsigned long raid5_cache_count(struct shrinker
*shrink
,
6423 struct shrink_control
*sc
)
6425 struct r5conf
*conf
= container_of(shrink
, struct r5conf
, shrinker
);
6427 if (conf
->max_nr_stripes
< conf
->min_nr_stripes
)
6428 /* unlikely, but not impossible */
6430 return conf
->max_nr_stripes
- conf
->min_nr_stripes
;
6433 static struct r5conf
*setup_conf(struct mddev
*mddev
)
6435 struct r5conf
*conf
;
6436 int raid_disk
, memory
, max_disks
;
6437 struct md_rdev
*rdev
;
6438 struct disk_info
*disk
;
6441 int group_cnt
, worker_cnt_per_group
;
6442 struct r5worker_group
*new_group
;
6444 if (mddev
->new_level
!= 5
6445 && mddev
->new_level
!= 4
6446 && mddev
->new_level
!= 6) {
6447 printk(KERN_ERR
"md/raid:%s: raid level not set to 4/5/6 (%d)\n",
6448 mdname(mddev
), mddev
->new_level
);
6449 return ERR_PTR(-EIO
);
6451 if ((mddev
->new_level
== 5
6452 && !algorithm_valid_raid5(mddev
->new_layout
)) ||
6453 (mddev
->new_level
== 6
6454 && !algorithm_valid_raid6(mddev
->new_layout
))) {
6455 printk(KERN_ERR
"md/raid:%s: layout %d not supported\n",
6456 mdname(mddev
), mddev
->new_layout
);
6457 return ERR_PTR(-EIO
);
6459 if (mddev
->new_level
== 6 && mddev
->raid_disks
< 4) {
6460 printk(KERN_ERR
"md/raid:%s: not enough configured devices (%d, minimum 4)\n",
6461 mdname(mddev
), mddev
->raid_disks
);
6462 return ERR_PTR(-EINVAL
);
6465 if (!mddev
->new_chunk_sectors
||
6466 (mddev
->new_chunk_sectors
<< 9) % PAGE_SIZE
||
6467 !is_power_of_2(mddev
->new_chunk_sectors
)) {
6468 printk(KERN_ERR
"md/raid:%s: invalid chunk size %d\n",
6469 mdname(mddev
), mddev
->new_chunk_sectors
<< 9);
6470 return ERR_PTR(-EINVAL
);
6473 conf
= kzalloc(sizeof(struct r5conf
), GFP_KERNEL
);
6476 /* Don't enable multi-threading by default*/
6477 if (!alloc_thread_groups(conf
, 0, &group_cnt
, &worker_cnt_per_group
,
6479 conf
->group_cnt
= group_cnt
;
6480 conf
->worker_cnt_per_group
= worker_cnt_per_group
;
6481 conf
->worker_groups
= new_group
;
6484 spin_lock_init(&conf
->device_lock
);
6485 seqcount_init(&conf
->gen_lock
);
6486 mutex_init(&conf
->cache_size_mutex
);
6487 init_waitqueue_head(&conf
->wait_for_quiescent
);
6488 for (i
= 0; i
< NR_STRIPE_HASH_LOCKS
; i
++) {
6489 init_waitqueue_head(&conf
->wait_for_stripe
[i
]);
6491 init_waitqueue_head(&conf
->wait_for_overlap
);
6492 INIT_LIST_HEAD(&conf
->handle_list
);
6493 INIT_LIST_HEAD(&conf
->hold_list
);
6494 INIT_LIST_HEAD(&conf
->delayed_list
);
6495 INIT_LIST_HEAD(&conf
->bitmap_list
);
6496 bio_list_init(&conf
->return_bi
);
6497 init_llist_head(&conf
->released_stripes
);
6498 atomic_set(&conf
->active_stripes
, 0);
6499 atomic_set(&conf
->preread_active_stripes
, 0);
6500 atomic_set(&conf
->active_aligned_reads
, 0);
6501 conf
->bypass_threshold
= BYPASS_THRESHOLD
;
6502 conf
->recovery_disabled
= mddev
->recovery_disabled
- 1;
6504 conf
->raid_disks
= mddev
->raid_disks
;
6505 if (mddev
->reshape_position
== MaxSector
)
6506 conf
->previous_raid_disks
= mddev
->raid_disks
;
6508 conf
->previous_raid_disks
= mddev
->raid_disks
- mddev
->delta_disks
;
6509 max_disks
= max(conf
->raid_disks
, conf
->previous_raid_disks
);
6511 conf
->disks
= kzalloc(max_disks
* sizeof(struct disk_info
),
6516 conf
->mddev
= mddev
;
6518 if ((conf
->stripe_hashtbl
= kzalloc(PAGE_SIZE
, GFP_KERNEL
)) == NULL
)
6521 /* We init hash_locks[0] separately to that it can be used
6522 * as the reference lock in the spin_lock_nest_lock() call
6523 * in lock_all_device_hash_locks_irq in order to convince
6524 * lockdep that we know what we are doing.
6526 spin_lock_init(conf
->hash_locks
);
6527 for (i
= 1; i
< NR_STRIPE_HASH_LOCKS
; i
++)
6528 spin_lock_init(conf
->hash_locks
+ i
);
6530 for (i
= 0; i
< NR_STRIPE_HASH_LOCKS
; i
++)
6531 INIT_LIST_HEAD(conf
->inactive_list
+ i
);
6533 for (i
= 0; i
< NR_STRIPE_HASH_LOCKS
; i
++)
6534 INIT_LIST_HEAD(conf
->temp_inactive_list
+ i
);
6536 conf
->level
= mddev
->new_level
;
6537 conf
->chunk_sectors
= mddev
->new_chunk_sectors
;
6538 if (raid5_alloc_percpu(conf
) != 0)
6541 pr_debug("raid456: run(%s) called.\n", mdname(mddev
));
6543 rdev_for_each(rdev
, mddev
) {
6544 raid_disk
= rdev
->raid_disk
;
6545 if (raid_disk
>= max_disks
6548 disk
= conf
->disks
+ raid_disk
;
6550 if (test_bit(Replacement
, &rdev
->flags
)) {
6551 if (disk
->replacement
)
6553 disk
->replacement
= rdev
;
6560 if (test_bit(In_sync
, &rdev
->flags
)) {
6561 char b
[BDEVNAME_SIZE
];
6562 printk(KERN_INFO
"md/raid:%s: device %s operational as raid"
6564 mdname(mddev
), bdevname(rdev
->bdev
, b
), raid_disk
);
6565 } else if (rdev
->saved_raid_disk
!= raid_disk
)
6566 /* Cannot rely on bitmap to complete recovery */
6570 conf
->level
= mddev
->new_level
;
6571 if (conf
->level
== 6) {
6572 conf
->max_degraded
= 2;
6573 if (raid6_call
.xor_syndrome
)
6574 conf
->rmw_level
= PARITY_ENABLE_RMW
;
6576 conf
->rmw_level
= PARITY_DISABLE_RMW
;
6578 conf
->max_degraded
= 1;
6579 conf
->rmw_level
= PARITY_ENABLE_RMW
;
6581 conf
->algorithm
= mddev
->new_layout
;
6582 conf
->reshape_progress
= mddev
->reshape_position
;
6583 if (conf
->reshape_progress
!= MaxSector
) {
6584 conf
->prev_chunk_sectors
= mddev
->chunk_sectors
;
6585 conf
->prev_algo
= mddev
->layout
;
6587 conf
->prev_chunk_sectors
= conf
->chunk_sectors
;
6588 conf
->prev_algo
= conf
->algorithm
;
6591 conf
->min_nr_stripes
= NR_STRIPES
;
6592 memory
= conf
->min_nr_stripes
* (sizeof(struct stripe_head
) +
6593 max_disks
* ((sizeof(struct bio
) + PAGE_SIZE
))) / 1024;
6594 atomic_set(&conf
->empty_inactive_list_nr
, NR_STRIPE_HASH_LOCKS
);
6595 if (grow_stripes(conf
, conf
->min_nr_stripes
)) {
6597 "md/raid:%s: couldn't allocate %dkB for buffers\n",
6598 mdname(mddev
), memory
);
6601 printk(KERN_INFO
"md/raid:%s: allocated %dkB\n",
6602 mdname(mddev
), memory
);
6604 * Losing a stripe head costs more than the time to refill it,
6605 * it reduces the queue depth and so can hurt throughput.
6606 * So set it rather large, scaled by number of devices.
6608 conf
->shrinker
.seeks
= DEFAULT_SEEKS
* conf
->raid_disks
* 4;
6609 conf
->shrinker
.scan_objects
= raid5_cache_scan
;
6610 conf
->shrinker
.count_objects
= raid5_cache_count
;
6611 conf
->shrinker
.batch
= 128;
6612 conf
->shrinker
.flags
= 0;
6613 register_shrinker(&conf
->shrinker
);
6615 sprintf(pers_name
, "raid%d", mddev
->new_level
);
6616 conf
->thread
= md_register_thread(raid5d
, mddev
, pers_name
);
6617 if (!conf
->thread
) {
6619 "md/raid:%s: couldn't allocate thread.\n",
6629 return ERR_PTR(-EIO
);
6631 return ERR_PTR(-ENOMEM
);
6634 static int only_parity(int raid_disk
, int algo
, int raid_disks
, int max_degraded
)
6637 case ALGORITHM_PARITY_0
:
6638 if (raid_disk
< max_degraded
)
6641 case ALGORITHM_PARITY_N
:
6642 if (raid_disk
>= raid_disks
- max_degraded
)
6645 case ALGORITHM_PARITY_0_6
:
6646 if (raid_disk
== 0 ||
6647 raid_disk
== raid_disks
- 1)
6650 case ALGORITHM_LEFT_ASYMMETRIC_6
:
6651 case ALGORITHM_RIGHT_ASYMMETRIC_6
:
6652 case ALGORITHM_LEFT_SYMMETRIC_6
:
6653 case ALGORITHM_RIGHT_SYMMETRIC_6
:
6654 if (raid_disk
== raid_disks
- 1)
6660 static int run(struct mddev
*mddev
)
6662 struct r5conf
*conf
;
6663 int working_disks
= 0;
6664 int dirty_parity_disks
= 0;
6665 struct md_rdev
*rdev
;
6666 struct md_rdev
*journal_dev
= NULL
;
6667 sector_t reshape_offset
= 0;
6669 long long min_offset_diff
= 0;
6672 if (mddev
->recovery_cp
!= MaxSector
)
6673 printk(KERN_NOTICE
"md/raid:%s: not clean"
6674 " -- starting background reconstruction\n",
6677 rdev_for_each(rdev
, mddev
) {
6680 if (test_bit(Journal
, &rdev
->flags
))
6682 if (rdev
->raid_disk
< 0)
6684 diff
= (rdev
->new_data_offset
- rdev
->data_offset
);
6686 min_offset_diff
= diff
;
6688 } else if (mddev
->reshape_backwards
&&
6689 diff
< min_offset_diff
)
6690 min_offset_diff
= diff
;
6691 else if (!mddev
->reshape_backwards
&&
6692 diff
> min_offset_diff
)
6693 min_offset_diff
= diff
;
6696 if (mddev
->reshape_position
!= MaxSector
) {
6697 /* Check that we can continue the reshape.
6698 * Difficulties arise if the stripe we would write to
6699 * next is at or after the stripe we would read from next.
6700 * For a reshape that changes the number of devices, this
6701 * is only possible for a very short time, and mdadm makes
6702 * sure that time appears to have past before assembling
6703 * the array. So we fail if that time hasn't passed.
6704 * For a reshape that keeps the number of devices the same
6705 * mdadm must be monitoring the reshape can keeping the
6706 * critical areas read-only and backed up. It will start
6707 * the array in read-only mode, so we check for that.
6709 sector_t here_new
, here_old
;
6711 int max_degraded
= (mddev
->level
== 6 ? 2 : 1);
6716 printk(KERN_ERR
"md/raid:%s: don't support reshape with journal - aborting.\n",
6721 if (mddev
->new_level
!= mddev
->level
) {
6722 printk(KERN_ERR
"md/raid:%s: unsupported reshape "
6723 "required - aborting.\n",
6727 old_disks
= mddev
->raid_disks
- mddev
->delta_disks
;
6728 /* reshape_position must be on a new-stripe boundary, and one
6729 * further up in new geometry must map after here in old
6731 * If the chunk sizes are different, then as we perform reshape
6732 * in units of the largest of the two, reshape_position needs
6733 * be a multiple of the largest chunk size times new data disks.
6735 here_new
= mddev
->reshape_position
;
6736 chunk_sectors
= max(mddev
->chunk_sectors
, mddev
->new_chunk_sectors
);
6737 new_data_disks
= mddev
->raid_disks
- max_degraded
;
6738 if (sector_div(here_new
, chunk_sectors
* new_data_disks
)) {
6739 printk(KERN_ERR
"md/raid:%s: reshape_position not "
6740 "on a stripe boundary\n", mdname(mddev
));
6743 reshape_offset
= here_new
* chunk_sectors
;
6744 /* here_new is the stripe we will write to */
6745 here_old
= mddev
->reshape_position
;
6746 sector_div(here_old
, chunk_sectors
* (old_disks
-max_degraded
));
6747 /* here_old is the first stripe that we might need to read
6749 if (mddev
->delta_disks
== 0) {
6750 /* We cannot be sure it is safe to start an in-place
6751 * reshape. It is only safe if user-space is monitoring
6752 * and taking constant backups.
6753 * mdadm always starts a situation like this in
6754 * readonly mode so it can take control before
6755 * allowing any writes. So just check for that.
6757 if (abs(min_offset_diff
) >= mddev
->chunk_sectors
&&
6758 abs(min_offset_diff
) >= mddev
->new_chunk_sectors
)
6759 /* not really in-place - so OK */;
6760 else if (mddev
->ro
== 0) {
6761 printk(KERN_ERR
"md/raid:%s: in-place reshape "
6762 "must be started in read-only mode "
6767 } else if (mddev
->reshape_backwards
6768 ? (here_new
* chunk_sectors
+ min_offset_diff
<=
6769 here_old
* chunk_sectors
)
6770 : (here_new
* chunk_sectors
>=
6771 here_old
* chunk_sectors
+ (-min_offset_diff
))) {
6772 /* Reading from the same stripe as writing to - bad */
6773 printk(KERN_ERR
"md/raid:%s: reshape_position too early for "
6774 "auto-recovery - aborting.\n",
6778 printk(KERN_INFO
"md/raid:%s: reshape will continue\n",
6780 /* OK, we should be able to continue; */
6782 BUG_ON(mddev
->level
!= mddev
->new_level
);
6783 BUG_ON(mddev
->layout
!= mddev
->new_layout
);
6784 BUG_ON(mddev
->chunk_sectors
!= mddev
->new_chunk_sectors
);
6785 BUG_ON(mddev
->delta_disks
!= 0);
6788 if (mddev
->private == NULL
)
6789 conf
= setup_conf(mddev
);
6791 conf
= mddev
->private;
6794 return PTR_ERR(conf
);
6796 conf
->min_offset_diff
= min_offset_diff
;
6797 mddev
->thread
= conf
->thread
;
6798 conf
->thread
= NULL
;
6799 mddev
->private = conf
;
6801 for (i
= 0; i
< conf
->raid_disks
&& conf
->previous_raid_disks
;
6803 rdev
= conf
->disks
[i
].rdev
;
6804 if (!rdev
&& conf
->disks
[i
].replacement
) {
6805 /* The replacement is all we have yet */
6806 rdev
= conf
->disks
[i
].replacement
;
6807 conf
->disks
[i
].replacement
= NULL
;
6808 clear_bit(Replacement
, &rdev
->flags
);
6809 conf
->disks
[i
].rdev
= rdev
;
6813 if (conf
->disks
[i
].replacement
&&
6814 conf
->reshape_progress
!= MaxSector
) {
6815 /* replacements and reshape simply do not mix. */
6816 printk(KERN_ERR
"md: cannot handle concurrent "
6817 "replacement and reshape.\n");
6820 if (test_bit(In_sync
, &rdev
->flags
)) {
6824 /* This disc is not fully in-sync. However if it
6825 * just stored parity (beyond the recovery_offset),
6826 * when we don't need to be concerned about the
6827 * array being dirty.
6828 * When reshape goes 'backwards', we never have
6829 * partially completed devices, so we only need
6830 * to worry about reshape going forwards.
6832 /* Hack because v0.91 doesn't store recovery_offset properly. */
6833 if (mddev
->major_version
== 0 &&
6834 mddev
->minor_version
> 90)
6835 rdev
->recovery_offset
= reshape_offset
;
6837 if (rdev
->recovery_offset
< reshape_offset
) {
6838 /* We need to check old and new layout */
6839 if (!only_parity(rdev
->raid_disk
,
6842 conf
->max_degraded
))
6845 if (!only_parity(rdev
->raid_disk
,
6847 conf
->previous_raid_disks
,
6848 conf
->max_degraded
))
6850 dirty_parity_disks
++;
6854 * 0 for a fully functional array, 1 or 2 for a degraded array.
6856 mddev
->degraded
= calc_degraded(conf
);
6858 if (has_failed(conf
)) {
6859 printk(KERN_ERR
"md/raid:%s: not enough operational devices"
6860 " (%d/%d failed)\n",
6861 mdname(mddev
), mddev
->degraded
, conf
->raid_disks
);
6865 /* device size must be a multiple of chunk size */
6866 mddev
->dev_sectors
&= ~(mddev
->chunk_sectors
- 1);
6867 mddev
->resync_max_sectors
= mddev
->dev_sectors
;
6869 if (mddev
->degraded
> dirty_parity_disks
&&
6870 mddev
->recovery_cp
!= MaxSector
) {
6871 if (mddev
->ok_start_degraded
)
6873 "md/raid:%s: starting dirty degraded array"
6874 " - data corruption possible.\n",
6878 "md/raid:%s: cannot start dirty degraded array.\n",
6884 if (mddev
->degraded
== 0)
6885 printk(KERN_INFO
"md/raid:%s: raid level %d active with %d out of %d"
6886 " devices, algorithm %d\n", mdname(mddev
), conf
->level
,
6887 mddev
->raid_disks
-mddev
->degraded
, mddev
->raid_disks
,
6890 printk(KERN_ALERT
"md/raid:%s: raid level %d active with %d"
6891 " out of %d devices, algorithm %d\n",
6892 mdname(mddev
), conf
->level
,
6893 mddev
->raid_disks
- mddev
->degraded
,
6894 mddev
->raid_disks
, mddev
->new_layout
);
6896 print_raid5_conf(conf
);
6898 if (conf
->reshape_progress
!= MaxSector
) {
6899 conf
->reshape_safe
= conf
->reshape_progress
;
6900 atomic_set(&conf
->reshape_stripes
, 0);
6901 clear_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
);
6902 clear_bit(MD_RECOVERY_CHECK
, &mddev
->recovery
);
6903 set_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
);
6904 set_bit(MD_RECOVERY_RUNNING
, &mddev
->recovery
);
6905 mddev
->sync_thread
= md_register_thread(md_do_sync
, mddev
,
6909 /* Ok, everything is just fine now */
6910 if (mddev
->to_remove
== &raid5_attrs_group
)
6911 mddev
->to_remove
= NULL
;
6912 else if (mddev
->kobj
.sd
&&
6913 sysfs_create_group(&mddev
->kobj
, &raid5_attrs_group
))
6915 "raid5: failed to create sysfs attributes for %s\n",
6917 md_set_array_sectors(mddev
, raid5_size(mddev
, 0, 0));
6921 bool discard_supported
= true;
6922 /* read-ahead size must cover two whole stripes, which
6923 * is 2 * (datadisks) * chunksize where 'n' is the
6924 * number of raid devices
6926 int data_disks
= conf
->previous_raid_disks
- conf
->max_degraded
;
6927 int stripe
= data_disks
*
6928 ((mddev
->chunk_sectors
<< 9) / PAGE_SIZE
);
6929 if (mddev
->queue
->backing_dev_info
.ra_pages
< 2 * stripe
)
6930 mddev
->queue
->backing_dev_info
.ra_pages
= 2 * stripe
;
6932 chunk_size
= mddev
->chunk_sectors
<< 9;
6933 blk_queue_io_min(mddev
->queue
, chunk_size
);
6934 blk_queue_io_opt(mddev
->queue
, chunk_size
*
6935 (conf
->raid_disks
- conf
->max_degraded
));
6936 mddev
->queue
->limits
.raid_partial_stripes_expensive
= 1;
6938 * We can only discard a whole stripe. It doesn't make sense to
6939 * discard data disk but write parity disk
6941 stripe
= stripe
* PAGE_SIZE
;
6942 /* Round up to power of 2, as discard handling
6943 * currently assumes that */
6944 while ((stripe
-1) & stripe
)
6945 stripe
= (stripe
| (stripe
-1)) + 1;
6946 mddev
->queue
->limits
.discard_alignment
= stripe
;
6947 mddev
->queue
->limits
.discard_granularity
= stripe
;
6949 * unaligned part of discard request will be ignored, so can't
6950 * guarantee discard_zeroes_data
6952 mddev
->queue
->limits
.discard_zeroes_data
= 0;
6954 blk_queue_max_write_same_sectors(mddev
->queue
, 0);
6956 rdev_for_each(rdev
, mddev
) {
6957 disk_stack_limits(mddev
->gendisk
, rdev
->bdev
,
6958 rdev
->data_offset
<< 9);
6959 disk_stack_limits(mddev
->gendisk
, rdev
->bdev
,
6960 rdev
->new_data_offset
<< 9);
6962 * discard_zeroes_data is required, otherwise data
6963 * could be lost. Consider a scenario: discard a stripe
6964 * (the stripe could be inconsistent if
6965 * discard_zeroes_data is 0); write one disk of the
6966 * stripe (the stripe could be inconsistent again
6967 * depending on which disks are used to calculate
6968 * parity); the disk is broken; The stripe data of this
6971 if (!blk_queue_discard(bdev_get_queue(rdev
->bdev
)) ||
6972 !bdev_get_queue(rdev
->bdev
)->
6973 limits
.discard_zeroes_data
)
6974 discard_supported
= false;
6975 /* Unfortunately, discard_zeroes_data is not currently
6976 * a guarantee - just a hint. So we only allow DISCARD
6977 * if the sysadmin has confirmed that only safe devices
6978 * are in use by setting a module parameter.
6980 if (!devices_handle_discard_safely
) {
6981 if (discard_supported
) {
6982 pr_info("md/raid456: discard support disabled due to uncertainty.\n");
6983 pr_info("Set raid456.devices_handle_discard_safely=Y to override.\n");
6985 discard_supported
= false;
6989 if (discard_supported
&&
6990 mddev
->queue
->limits
.max_discard_sectors
>= stripe
&&
6991 mddev
->queue
->limits
.discard_granularity
>= stripe
)
6992 queue_flag_set_unlocked(QUEUE_FLAG_DISCARD
,
6995 queue_flag_clear_unlocked(QUEUE_FLAG_DISCARD
,
7001 md_unregister_thread(&mddev
->thread
);
7002 print_raid5_conf(conf
);
7004 mddev
->private = NULL
;
7005 printk(KERN_ALERT
"md/raid:%s: failed to run raid set.\n", mdname(mddev
));
7009 static void raid5_free(struct mddev
*mddev
, void *priv
)
7011 struct r5conf
*conf
= priv
;
7014 mddev
->to_remove
= &raid5_attrs_group
;
7017 static void status(struct seq_file
*seq
, struct mddev
*mddev
)
7019 struct r5conf
*conf
= mddev
->private;
7022 seq_printf(seq
, " level %d, %dk chunk, algorithm %d", mddev
->level
,
7023 conf
->chunk_sectors
/ 2, mddev
->layout
);
7024 seq_printf (seq
, " [%d/%d] [", conf
->raid_disks
, conf
->raid_disks
- mddev
->degraded
);
7025 for (i
= 0; i
< conf
->raid_disks
; i
++)
7026 seq_printf (seq
, "%s",
7027 conf
->disks
[i
].rdev
&&
7028 test_bit(In_sync
, &conf
->disks
[i
].rdev
->flags
) ? "U" : "_");
7029 seq_printf (seq
, "]");
7032 static void print_raid5_conf (struct r5conf
*conf
)
7035 struct disk_info
*tmp
;
7037 printk(KERN_DEBUG
"RAID conf printout:\n");
7039 printk("(conf==NULL)\n");
7042 printk(KERN_DEBUG
" --- level:%d rd:%d wd:%d\n", conf
->level
,
7044 conf
->raid_disks
- conf
->mddev
->degraded
);
7046 for (i
= 0; i
< conf
->raid_disks
; i
++) {
7047 char b
[BDEVNAME_SIZE
];
7048 tmp
= conf
->disks
+ i
;
7050 printk(KERN_DEBUG
" disk %d, o:%d, dev:%s\n",
7051 i
, !test_bit(Faulty
, &tmp
->rdev
->flags
),
7052 bdevname(tmp
->rdev
->bdev
, b
));
7056 static int raid5_spare_active(struct mddev
*mddev
)
7059 struct r5conf
*conf
= mddev
->private;
7060 struct disk_info
*tmp
;
7062 unsigned long flags
;
7064 for (i
= 0; i
< conf
->raid_disks
; i
++) {
7065 tmp
= conf
->disks
+ i
;
7066 if (tmp
->replacement
7067 && tmp
->replacement
->recovery_offset
== MaxSector
7068 && !test_bit(Faulty
, &tmp
->replacement
->flags
)
7069 && !test_and_set_bit(In_sync
, &tmp
->replacement
->flags
)) {
7070 /* Replacement has just become active. */
7072 || !test_and_clear_bit(In_sync
, &tmp
->rdev
->flags
))
7075 /* Replaced device not technically faulty,
7076 * but we need to be sure it gets removed
7077 * and never re-added.
7079 set_bit(Faulty
, &tmp
->rdev
->flags
);
7080 sysfs_notify_dirent_safe(
7081 tmp
->rdev
->sysfs_state
);
7083 sysfs_notify_dirent_safe(tmp
->replacement
->sysfs_state
);
7084 } else if (tmp
->rdev
7085 && tmp
->rdev
->recovery_offset
== MaxSector
7086 && !test_bit(Faulty
, &tmp
->rdev
->flags
)
7087 && !test_and_set_bit(In_sync
, &tmp
->rdev
->flags
)) {
7089 sysfs_notify_dirent_safe(tmp
->rdev
->sysfs_state
);
7092 spin_lock_irqsave(&conf
->device_lock
, flags
);
7093 mddev
->degraded
= calc_degraded(conf
);
7094 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
7095 print_raid5_conf(conf
);
7099 static int raid5_remove_disk(struct mddev
*mddev
, struct md_rdev
*rdev
)
7101 struct r5conf
*conf
= mddev
->private;
7103 int number
= rdev
->raid_disk
;
7104 struct md_rdev
**rdevp
;
7105 struct disk_info
*p
= conf
->disks
+ number
;
7107 print_raid5_conf(conf
);
7108 if (rdev
== p
->rdev
)
7110 else if (rdev
== p
->replacement
)
7111 rdevp
= &p
->replacement
;
7115 if (number
>= conf
->raid_disks
&&
7116 conf
->reshape_progress
== MaxSector
)
7117 clear_bit(In_sync
, &rdev
->flags
);
7119 if (test_bit(In_sync
, &rdev
->flags
) ||
7120 atomic_read(&rdev
->nr_pending
)) {
7124 /* Only remove non-faulty devices if recovery
7127 if (!test_bit(Faulty
, &rdev
->flags
) &&
7128 mddev
->recovery_disabled
!= conf
->recovery_disabled
&&
7129 !has_failed(conf
) &&
7130 (!p
->replacement
|| p
->replacement
== rdev
) &&
7131 number
< conf
->raid_disks
) {
7137 if (atomic_read(&rdev
->nr_pending
)) {
7138 /* lost the race, try later */
7141 } else if (p
->replacement
) {
7142 /* We must have just cleared 'rdev' */
7143 p
->rdev
= p
->replacement
;
7144 clear_bit(Replacement
, &p
->replacement
->flags
);
7145 smp_mb(); /* Make sure other CPUs may see both as identical
7146 * but will never see neither - if they are careful
7148 p
->replacement
= NULL
;
7149 clear_bit(WantReplacement
, &rdev
->flags
);
7151 /* We might have just removed the Replacement as faulty-
7152 * clear the bit just in case
7154 clear_bit(WantReplacement
, &rdev
->flags
);
7157 print_raid5_conf(conf
);
7161 static int raid5_add_disk(struct mddev
*mddev
, struct md_rdev
*rdev
)
7163 struct r5conf
*conf
= mddev
->private;
7166 struct disk_info
*p
;
7168 int last
= conf
->raid_disks
- 1;
7170 if (mddev
->recovery_disabled
== conf
->recovery_disabled
)
7173 if (rdev
->saved_raid_disk
< 0 && has_failed(conf
))
7174 /* no point adding a device */
7177 if (rdev
->raid_disk
>= 0)
7178 first
= last
= rdev
->raid_disk
;
7181 * find the disk ... but prefer rdev->saved_raid_disk
7184 if (rdev
->saved_raid_disk
>= 0 &&
7185 rdev
->saved_raid_disk
>= first
&&
7186 conf
->disks
[rdev
->saved_raid_disk
].rdev
== NULL
)
7187 first
= rdev
->saved_raid_disk
;
7189 for (disk
= first
; disk
<= last
; disk
++) {
7190 p
= conf
->disks
+ disk
;
7191 if (p
->rdev
== NULL
) {
7192 clear_bit(In_sync
, &rdev
->flags
);
7193 rdev
->raid_disk
= disk
;
7195 if (rdev
->saved_raid_disk
!= disk
)
7197 rcu_assign_pointer(p
->rdev
, rdev
);
7201 for (disk
= first
; disk
<= last
; disk
++) {
7202 p
= conf
->disks
+ disk
;
7203 if (test_bit(WantReplacement
, &p
->rdev
->flags
) &&
7204 p
->replacement
== NULL
) {
7205 clear_bit(In_sync
, &rdev
->flags
);
7206 set_bit(Replacement
, &rdev
->flags
);
7207 rdev
->raid_disk
= disk
;
7210 rcu_assign_pointer(p
->replacement
, rdev
);
7215 print_raid5_conf(conf
);
7219 static int raid5_resize(struct mddev
*mddev
, sector_t sectors
)
7221 /* no resync is happening, and there is enough space
7222 * on all devices, so we can resize.
7223 * We need to make sure resync covers any new space.
7224 * If the array is shrinking we should possibly wait until
7225 * any io in the removed space completes, but it hardly seems
7229 struct r5conf
*conf
= mddev
->private;
7233 sectors
&= ~((sector_t
)conf
->chunk_sectors
- 1);
7234 newsize
= raid5_size(mddev
, sectors
, mddev
->raid_disks
);
7235 if (mddev
->external_size
&&
7236 mddev
->array_sectors
> newsize
)
7238 if (mddev
->bitmap
) {
7239 int ret
= bitmap_resize(mddev
->bitmap
, sectors
, 0, 0);
7243 md_set_array_sectors(mddev
, newsize
);
7244 set_capacity(mddev
->gendisk
, mddev
->array_sectors
);
7245 revalidate_disk(mddev
->gendisk
);
7246 if (sectors
> mddev
->dev_sectors
&&
7247 mddev
->recovery_cp
> mddev
->dev_sectors
) {
7248 mddev
->recovery_cp
= mddev
->dev_sectors
;
7249 set_bit(MD_RECOVERY_NEEDED
, &mddev
->recovery
);
7251 mddev
->dev_sectors
= sectors
;
7252 mddev
->resync_max_sectors
= sectors
;
7256 static int check_stripe_cache(struct mddev
*mddev
)
7258 /* Can only proceed if there are plenty of stripe_heads.
7259 * We need a minimum of one full stripe,, and for sensible progress
7260 * it is best to have about 4 times that.
7261 * If we require 4 times, then the default 256 4K stripe_heads will
7262 * allow for chunk sizes up to 256K, which is probably OK.
7263 * If the chunk size is greater, user-space should request more
7264 * stripe_heads first.
7266 struct r5conf
*conf
= mddev
->private;
7267 if (((mddev
->chunk_sectors
<< 9) / STRIPE_SIZE
) * 4
7268 > conf
->min_nr_stripes
||
7269 ((mddev
->new_chunk_sectors
<< 9) / STRIPE_SIZE
) * 4
7270 > conf
->min_nr_stripes
) {
7271 printk(KERN_WARNING
"md/raid:%s: reshape: not enough stripes. Needed %lu\n",
7273 ((max(mddev
->chunk_sectors
, mddev
->new_chunk_sectors
) << 9)
7280 static int check_reshape(struct mddev
*mddev
)
7282 struct r5conf
*conf
= mddev
->private;
7286 if (mddev
->delta_disks
== 0 &&
7287 mddev
->new_layout
== mddev
->layout
&&
7288 mddev
->new_chunk_sectors
== mddev
->chunk_sectors
)
7289 return 0; /* nothing to do */
7290 if (has_failed(conf
))
7292 if (mddev
->delta_disks
< 0 && mddev
->reshape_position
== MaxSector
) {
7293 /* We might be able to shrink, but the devices must
7294 * be made bigger first.
7295 * For raid6, 4 is the minimum size.
7296 * Otherwise 2 is the minimum
7299 if (mddev
->level
== 6)
7301 if (mddev
->raid_disks
+ mddev
->delta_disks
< min
)
7305 if (!check_stripe_cache(mddev
))
7308 if (mddev
->new_chunk_sectors
> mddev
->chunk_sectors
||
7309 mddev
->delta_disks
> 0)
7310 if (resize_chunks(conf
,
7311 conf
->previous_raid_disks
7312 + max(0, mddev
->delta_disks
),
7313 max(mddev
->new_chunk_sectors
,
7314 mddev
->chunk_sectors
)
7317 return resize_stripes(conf
, (conf
->previous_raid_disks
7318 + mddev
->delta_disks
));
7321 static int raid5_start_reshape(struct mddev
*mddev
)
7323 struct r5conf
*conf
= mddev
->private;
7324 struct md_rdev
*rdev
;
7326 unsigned long flags
;
7328 if (test_bit(MD_RECOVERY_RUNNING
, &mddev
->recovery
))
7331 if (!check_stripe_cache(mddev
))
7334 if (has_failed(conf
))
7337 rdev_for_each(rdev
, mddev
) {
7338 if (!test_bit(In_sync
, &rdev
->flags
)
7339 && !test_bit(Faulty
, &rdev
->flags
))
7343 if (spares
- mddev
->degraded
< mddev
->delta_disks
- conf
->max_degraded
)
7344 /* Not enough devices even to make a degraded array
7349 /* Refuse to reduce size of the array. Any reductions in
7350 * array size must be through explicit setting of array_size
7353 if (raid5_size(mddev
, 0, conf
->raid_disks
+ mddev
->delta_disks
)
7354 < mddev
->array_sectors
) {
7355 printk(KERN_ERR
"md/raid:%s: array size must be reduced "
7356 "before number of disks\n", mdname(mddev
));
7360 atomic_set(&conf
->reshape_stripes
, 0);
7361 spin_lock_irq(&conf
->device_lock
);
7362 write_seqcount_begin(&conf
->gen_lock
);
7363 conf
->previous_raid_disks
= conf
->raid_disks
;
7364 conf
->raid_disks
+= mddev
->delta_disks
;
7365 conf
->prev_chunk_sectors
= conf
->chunk_sectors
;
7366 conf
->chunk_sectors
= mddev
->new_chunk_sectors
;
7367 conf
->prev_algo
= conf
->algorithm
;
7368 conf
->algorithm
= mddev
->new_layout
;
7370 /* Code that selects data_offset needs to see the generation update
7371 * if reshape_progress has been set - so a memory barrier needed.
7374 if (mddev
->reshape_backwards
)
7375 conf
->reshape_progress
= raid5_size(mddev
, 0, 0);
7377 conf
->reshape_progress
= 0;
7378 conf
->reshape_safe
= conf
->reshape_progress
;
7379 write_seqcount_end(&conf
->gen_lock
);
7380 spin_unlock_irq(&conf
->device_lock
);
7382 /* Now make sure any requests that proceeded on the assumption
7383 * the reshape wasn't running - like Discard or Read - have
7386 mddev_suspend(mddev
);
7387 mddev_resume(mddev
);
7389 /* Add some new drives, as many as will fit.
7390 * We know there are enough to make the newly sized array work.
7391 * Don't add devices if we are reducing the number of
7392 * devices in the array. This is because it is not possible
7393 * to correctly record the "partially reconstructed" state of
7394 * such devices during the reshape and confusion could result.
7396 if (mddev
->delta_disks
>= 0) {
7397 rdev_for_each(rdev
, mddev
)
7398 if (rdev
->raid_disk
< 0 &&
7399 !test_bit(Faulty
, &rdev
->flags
)) {
7400 if (raid5_add_disk(mddev
, rdev
) == 0) {
7402 >= conf
->previous_raid_disks
)
7403 set_bit(In_sync
, &rdev
->flags
);
7405 rdev
->recovery_offset
= 0;
7407 if (sysfs_link_rdev(mddev
, rdev
))
7408 /* Failure here is OK */;
7410 } else if (rdev
->raid_disk
>= conf
->previous_raid_disks
7411 && !test_bit(Faulty
, &rdev
->flags
)) {
7412 /* This is a spare that was manually added */
7413 set_bit(In_sync
, &rdev
->flags
);
7416 /* When a reshape changes the number of devices,
7417 * ->degraded is measured against the larger of the
7418 * pre and post number of devices.
7420 spin_lock_irqsave(&conf
->device_lock
, flags
);
7421 mddev
->degraded
= calc_degraded(conf
);
7422 spin_unlock_irqrestore(&conf
->device_lock
, flags
);
7424 mddev
->raid_disks
= conf
->raid_disks
;
7425 mddev
->reshape_position
= conf
->reshape_progress
;
7426 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
7428 clear_bit(MD_RECOVERY_SYNC
, &mddev
->recovery
);
7429 clear_bit(MD_RECOVERY_CHECK
, &mddev
->recovery
);
7430 clear_bit(MD_RECOVERY_DONE
, &mddev
->recovery
);
7431 set_bit(MD_RECOVERY_RESHAPE
, &mddev
->recovery
);
7432 set_bit(MD_RECOVERY_RUNNING
, &mddev
->recovery
);
7433 mddev
->sync_thread
= md_register_thread(md_do_sync
, mddev
,
7435 if (!mddev
->sync_thread
) {
7436 mddev
->recovery
= 0;
7437 spin_lock_irq(&conf
->device_lock
);
7438 write_seqcount_begin(&conf
->gen_lock
);
7439 mddev
->raid_disks
= conf
->raid_disks
= conf
->previous_raid_disks
;
7440 mddev
->new_chunk_sectors
=
7441 conf
->chunk_sectors
= conf
->prev_chunk_sectors
;
7442 mddev
->new_layout
= conf
->algorithm
= conf
->prev_algo
;
7443 rdev_for_each(rdev
, mddev
)
7444 rdev
->new_data_offset
= rdev
->data_offset
;
7446 conf
->generation
--;
7447 conf
->reshape_progress
= MaxSector
;
7448 mddev
->reshape_position
= MaxSector
;
7449 write_seqcount_end(&conf
->gen_lock
);
7450 spin_unlock_irq(&conf
->device_lock
);
7453 conf
->reshape_checkpoint
= jiffies
;
7454 md_wakeup_thread(mddev
->sync_thread
);
7455 md_new_event(mddev
);
7459 /* This is called from the reshape thread and should make any
7460 * changes needed in 'conf'
7462 static void end_reshape(struct r5conf
*conf
)
7465 if (!test_bit(MD_RECOVERY_INTR
, &conf
->mddev
->recovery
)) {
7466 struct md_rdev
*rdev
;
7468 spin_lock_irq(&conf
->device_lock
);
7469 conf
->previous_raid_disks
= conf
->raid_disks
;
7470 rdev_for_each(rdev
, conf
->mddev
)
7471 rdev
->data_offset
= rdev
->new_data_offset
;
7473 conf
->reshape_progress
= MaxSector
;
7474 conf
->mddev
->reshape_position
= MaxSector
;
7475 spin_unlock_irq(&conf
->device_lock
);
7476 wake_up(&conf
->wait_for_overlap
);
7478 /* read-ahead size must cover two whole stripes, which is
7479 * 2 * (datadisks) * chunksize where 'n' is the number of raid devices
7481 if (conf
->mddev
->queue
) {
7482 int data_disks
= conf
->raid_disks
- conf
->max_degraded
;
7483 int stripe
= data_disks
* ((conf
->chunk_sectors
<< 9)
7485 if (conf
->mddev
->queue
->backing_dev_info
.ra_pages
< 2 * stripe
)
7486 conf
->mddev
->queue
->backing_dev_info
.ra_pages
= 2 * stripe
;
7491 /* This is called from the raid5d thread with mddev_lock held.
7492 * It makes config changes to the device.
7494 static void raid5_finish_reshape(struct mddev
*mddev
)
7496 struct r5conf
*conf
= mddev
->private;
7498 if (!test_bit(MD_RECOVERY_INTR
, &mddev
->recovery
)) {
7500 if (mddev
->delta_disks
> 0) {
7501 md_set_array_sectors(mddev
, raid5_size(mddev
, 0, 0));
7502 set_capacity(mddev
->gendisk
, mddev
->array_sectors
);
7503 revalidate_disk(mddev
->gendisk
);
7506 spin_lock_irq(&conf
->device_lock
);
7507 mddev
->degraded
= calc_degraded(conf
);
7508 spin_unlock_irq(&conf
->device_lock
);
7509 for (d
= conf
->raid_disks
;
7510 d
< conf
->raid_disks
- mddev
->delta_disks
;
7512 struct md_rdev
*rdev
= conf
->disks
[d
].rdev
;
7514 clear_bit(In_sync
, &rdev
->flags
);
7515 rdev
= conf
->disks
[d
].replacement
;
7517 clear_bit(In_sync
, &rdev
->flags
);
7520 mddev
->layout
= conf
->algorithm
;
7521 mddev
->chunk_sectors
= conf
->chunk_sectors
;
7522 mddev
->reshape_position
= MaxSector
;
7523 mddev
->delta_disks
= 0;
7524 mddev
->reshape_backwards
= 0;
7528 static void raid5_quiesce(struct mddev
*mddev
, int state
)
7530 struct r5conf
*conf
= mddev
->private;
7533 case 2: /* resume for a suspend */
7534 wake_up(&conf
->wait_for_overlap
);
7537 case 1: /* stop all writes */
7538 lock_all_device_hash_locks_irq(conf
);
7539 /* '2' tells resync/reshape to pause so that all
7540 * active stripes can drain
7543 wait_event_cmd(conf
->wait_for_quiescent
,
7544 atomic_read(&conf
->active_stripes
) == 0 &&
7545 atomic_read(&conf
->active_aligned_reads
) == 0,
7546 unlock_all_device_hash_locks_irq(conf
),
7547 lock_all_device_hash_locks_irq(conf
));
7549 unlock_all_device_hash_locks_irq(conf
);
7550 /* allow reshape to continue */
7551 wake_up(&conf
->wait_for_overlap
);
7554 case 0: /* re-enable writes */
7555 lock_all_device_hash_locks_irq(conf
);
7557 wake_up(&conf
->wait_for_quiescent
);
7558 wake_up(&conf
->wait_for_overlap
);
7559 unlock_all_device_hash_locks_irq(conf
);
7564 static void *raid45_takeover_raid0(struct mddev
*mddev
, int level
)
7566 struct r0conf
*raid0_conf
= mddev
->private;
7569 /* for raid0 takeover only one zone is supported */
7570 if (raid0_conf
->nr_strip_zones
> 1) {
7571 printk(KERN_ERR
"md/raid:%s: cannot takeover raid0 with more than one zone.\n",
7573 return ERR_PTR(-EINVAL
);
7576 sectors
= raid0_conf
->strip_zone
[0].zone_end
;
7577 sector_div(sectors
, raid0_conf
->strip_zone
[0].nb_dev
);
7578 mddev
->dev_sectors
= sectors
;
7579 mddev
->new_level
= level
;
7580 mddev
->new_layout
= ALGORITHM_PARITY_N
;
7581 mddev
->new_chunk_sectors
= mddev
->chunk_sectors
;
7582 mddev
->raid_disks
+= 1;
7583 mddev
->delta_disks
= 1;
7584 /* make sure it will be not marked as dirty */
7585 mddev
->recovery_cp
= MaxSector
;
7587 return setup_conf(mddev
);
7590 static void *raid5_takeover_raid1(struct mddev
*mddev
)
7594 if (mddev
->raid_disks
!= 2 ||
7595 mddev
->degraded
> 1)
7596 return ERR_PTR(-EINVAL
);
7598 /* Should check if there are write-behind devices? */
7600 chunksect
= 64*2; /* 64K by default */
7602 /* The array must be an exact multiple of chunksize */
7603 while (chunksect
&& (mddev
->array_sectors
& (chunksect
-1)))
7606 if ((chunksect
<<9) < STRIPE_SIZE
)
7607 /* array size does not allow a suitable chunk size */
7608 return ERR_PTR(-EINVAL
);
7610 mddev
->new_level
= 5;
7611 mddev
->new_layout
= ALGORITHM_LEFT_SYMMETRIC
;
7612 mddev
->new_chunk_sectors
= chunksect
;
7614 return setup_conf(mddev
);
7617 static void *raid5_takeover_raid6(struct mddev
*mddev
)
7621 switch (mddev
->layout
) {
7622 case ALGORITHM_LEFT_ASYMMETRIC_6
:
7623 new_layout
= ALGORITHM_LEFT_ASYMMETRIC
;
7625 case ALGORITHM_RIGHT_ASYMMETRIC_6
:
7626 new_layout
= ALGORITHM_RIGHT_ASYMMETRIC
;
7628 case ALGORITHM_LEFT_SYMMETRIC_6
:
7629 new_layout
= ALGORITHM_LEFT_SYMMETRIC
;
7631 case ALGORITHM_RIGHT_SYMMETRIC_6
:
7632 new_layout
= ALGORITHM_RIGHT_SYMMETRIC
;
7634 case ALGORITHM_PARITY_0_6
:
7635 new_layout
= ALGORITHM_PARITY_0
;
7637 case ALGORITHM_PARITY_N
:
7638 new_layout
= ALGORITHM_PARITY_N
;
7641 return ERR_PTR(-EINVAL
);
7643 mddev
->new_level
= 5;
7644 mddev
->new_layout
= new_layout
;
7645 mddev
->delta_disks
= -1;
7646 mddev
->raid_disks
-= 1;
7647 return setup_conf(mddev
);
7650 static int raid5_check_reshape(struct mddev
*mddev
)
7652 /* For a 2-drive array, the layout and chunk size can be changed
7653 * immediately as not restriping is needed.
7654 * For larger arrays we record the new value - after validation
7655 * to be used by a reshape pass.
7657 struct r5conf
*conf
= mddev
->private;
7658 int new_chunk
= mddev
->new_chunk_sectors
;
7660 if (mddev
->new_layout
>= 0 && !algorithm_valid_raid5(mddev
->new_layout
))
7662 if (new_chunk
> 0) {
7663 if (!is_power_of_2(new_chunk
))
7665 if (new_chunk
< (PAGE_SIZE
>>9))
7667 if (mddev
->array_sectors
& (new_chunk
-1))
7668 /* not factor of array size */
7672 /* They look valid */
7674 if (mddev
->raid_disks
== 2) {
7675 /* can make the change immediately */
7676 if (mddev
->new_layout
>= 0) {
7677 conf
->algorithm
= mddev
->new_layout
;
7678 mddev
->layout
= mddev
->new_layout
;
7680 if (new_chunk
> 0) {
7681 conf
->chunk_sectors
= new_chunk
;
7682 mddev
->chunk_sectors
= new_chunk
;
7684 set_bit(MD_CHANGE_DEVS
, &mddev
->flags
);
7685 md_wakeup_thread(mddev
->thread
);
7687 return check_reshape(mddev
);
7690 static int raid6_check_reshape(struct mddev
*mddev
)
7692 int new_chunk
= mddev
->new_chunk_sectors
;
7694 if (mddev
->new_layout
>= 0 && !algorithm_valid_raid6(mddev
->new_layout
))
7696 if (new_chunk
> 0) {
7697 if (!is_power_of_2(new_chunk
))
7699 if (new_chunk
< (PAGE_SIZE
>> 9))
7701 if (mddev
->array_sectors
& (new_chunk
-1))
7702 /* not factor of array size */
7706 /* They look valid */
7707 return check_reshape(mddev
);
7710 static void *raid5_takeover(struct mddev
*mddev
)
7712 /* raid5 can take over:
7713 * raid0 - if there is only one strip zone - make it a raid4 layout
7714 * raid1 - if there are two drives. We need to know the chunk size
7715 * raid4 - trivial - just use a raid4 layout.
7716 * raid6 - Providing it is a *_6 layout
7718 if (mddev
->level
== 0)
7719 return raid45_takeover_raid0(mddev
, 5);
7720 if (mddev
->level
== 1)
7721 return raid5_takeover_raid1(mddev
);
7722 if (mddev
->level
== 4) {
7723 mddev
->new_layout
= ALGORITHM_PARITY_N
;
7724 mddev
->new_level
= 5;
7725 return setup_conf(mddev
);
7727 if (mddev
->level
== 6)
7728 return raid5_takeover_raid6(mddev
);
7730 return ERR_PTR(-EINVAL
);
7733 static void *raid4_takeover(struct mddev
*mddev
)
7735 /* raid4 can take over:
7736 * raid0 - if there is only one strip zone
7737 * raid5 - if layout is right
7739 if (mddev
->level
== 0)
7740 return raid45_takeover_raid0(mddev
, 4);
7741 if (mddev
->level
== 5 &&
7742 mddev
->layout
== ALGORITHM_PARITY_N
) {
7743 mddev
->new_layout
= 0;
7744 mddev
->new_level
= 4;
7745 return setup_conf(mddev
);
7747 return ERR_PTR(-EINVAL
);
7750 static struct md_personality raid5_personality
;
7752 static void *raid6_takeover(struct mddev
*mddev
)
7754 /* Currently can only take over a raid5. We map the
7755 * personality to an equivalent raid6 personality
7756 * with the Q block at the end.
7760 if (mddev
->pers
!= &raid5_personality
)
7761 return ERR_PTR(-EINVAL
);
7762 if (mddev
->degraded
> 1)
7763 return ERR_PTR(-EINVAL
);
7764 if (mddev
->raid_disks
> 253)
7765 return ERR_PTR(-EINVAL
);
7766 if (mddev
->raid_disks
< 3)
7767 return ERR_PTR(-EINVAL
);
7769 switch (mddev
->layout
) {
7770 case ALGORITHM_LEFT_ASYMMETRIC
:
7771 new_layout
= ALGORITHM_LEFT_ASYMMETRIC_6
;
7773 case ALGORITHM_RIGHT_ASYMMETRIC
:
7774 new_layout
= ALGORITHM_RIGHT_ASYMMETRIC_6
;
7776 case ALGORITHM_LEFT_SYMMETRIC
:
7777 new_layout
= ALGORITHM_LEFT_SYMMETRIC_6
;
7779 case ALGORITHM_RIGHT_SYMMETRIC
:
7780 new_layout
= ALGORITHM_RIGHT_SYMMETRIC_6
;
7782 case ALGORITHM_PARITY_0
:
7783 new_layout
= ALGORITHM_PARITY_0_6
;
7785 case ALGORITHM_PARITY_N
:
7786 new_layout
= ALGORITHM_PARITY_N
;
7789 return ERR_PTR(-EINVAL
);
7791 mddev
->new_level
= 6;
7792 mddev
->new_layout
= new_layout
;
7793 mddev
->delta_disks
= 1;
7794 mddev
->raid_disks
+= 1;
7795 return setup_conf(mddev
);
7798 static struct md_personality raid6_personality
=
7802 .owner
= THIS_MODULE
,
7803 .make_request
= make_request
,
7807 .error_handler
= error
,
7808 .hot_add_disk
= raid5_add_disk
,
7809 .hot_remove_disk
= raid5_remove_disk
,
7810 .spare_active
= raid5_spare_active
,
7811 .sync_request
= sync_request
,
7812 .resize
= raid5_resize
,
7814 .check_reshape
= raid6_check_reshape
,
7815 .start_reshape
= raid5_start_reshape
,
7816 .finish_reshape
= raid5_finish_reshape
,
7817 .quiesce
= raid5_quiesce
,
7818 .takeover
= raid6_takeover
,
7819 .congested
= raid5_congested
,
7821 static struct md_personality raid5_personality
=
7825 .owner
= THIS_MODULE
,
7826 .make_request
= make_request
,
7830 .error_handler
= error
,
7831 .hot_add_disk
= raid5_add_disk
,
7832 .hot_remove_disk
= raid5_remove_disk
,
7833 .spare_active
= raid5_spare_active
,
7834 .sync_request
= sync_request
,
7835 .resize
= raid5_resize
,
7837 .check_reshape
= raid5_check_reshape
,
7838 .start_reshape
= raid5_start_reshape
,
7839 .finish_reshape
= raid5_finish_reshape
,
7840 .quiesce
= raid5_quiesce
,
7841 .takeover
= raid5_takeover
,
7842 .congested
= raid5_congested
,
7845 static struct md_personality raid4_personality
=
7849 .owner
= THIS_MODULE
,
7850 .make_request
= make_request
,
7854 .error_handler
= error
,
7855 .hot_add_disk
= raid5_add_disk
,
7856 .hot_remove_disk
= raid5_remove_disk
,
7857 .spare_active
= raid5_spare_active
,
7858 .sync_request
= sync_request
,
7859 .resize
= raid5_resize
,
7861 .check_reshape
= raid5_check_reshape
,
7862 .start_reshape
= raid5_start_reshape
,
7863 .finish_reshape
= raid5_finish_reshape
,
7864 .quiesce
= raid5_quiesce
,
7865 .takeover
= raid4_takeover
,
7866 .congested
= raid5_congested
,
7869 static int __init
raid5_init(void)
7871 raid5_wq
= alloc_workqueue("raid5wq",
7872 WQ_UNBOUND
|WQ_MEM_RECLAIM
|WQ_CPU_INTENSIVE
|WQ_SYSFS
, 0);
7875 register_md_personality(&raid6_personality
);
7876 register_md_personality(&raid5_personality
);
7877 register_md_personality(&raid4_personality
);
7881 static void raid5_exit(void)
7883 unregister_md_personality(&raid6_personality
);
7884 unregister_md_personality(&raid5_personality
);
7885 unregister_md_personality(&raid4_personality
);
7886 destroy_workqueue(raid5_wq
);
7889 module_init(raid5_init
);
7890 module_exit(raid5_exit
);
7891 MODULE_LICENSE("GPL");
7892 MODULE_DESCRIPTION("RAID4/5/6 (striping with parity) personality for MD");
7893 MODULE_ALIAS("md-personality-4"); /* RAID5 */
7894 MODULE_ALIAS("md-raid5");
7895 MODULE_ALIAS("md-raid4");
7896 MODULE_ALIAS("md-level-5");
7897 MODULE_ALIAS("md-level-4");
7898 MODULE_ALIAS("md-personality-8"); /* RAID6 */
7899 MODULE_ALIAS("md-raid6");
7900 MODULE_ALIAS("md-level-6");
7902 /* This used to be two separate modules, they were: */
7903 MODULE_ALIAS("raid5");
7904 MODULE_ALIAS("raid6");