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md/r5cache: remove redundant pointer bio
[linux-2.6-block.git] / drivers / md / raid5.c
CommitLineData
1da177e4
LT		 1/*
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
16a53ecc 5 * Copyright (C) 2002, 2003 H. Peter Anvin
1da177e4 6 *
16a53ecc
N		 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!
1da177e4
LT		 10 *
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)
14 * any later version.
15 *
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.
19 */
20
ae3c20cc
N		 21/*
22 * BITMAP UNPLUGGING:
23 *
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
26 * explanation.
27 *
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.
7c13edc8
N		 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
ae3c20cc
N		 32 * new additions.
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
7c13edc8 35 * the number of the batch it will be in. This is seq_flush+1.
ae3c20cc
N		 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
39 * batch.
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
43 * miss any bits.
44 */
1da177e4 45
bff61975 46#include <linux/blkdev.h>
f6705578 47#include <linux/kthread.h>
f701d589 48#include <linux/raid/pq.h>
91c00924 49#include <linux/async_tx.h>
056075c7 50#include <linux/module.h>
07a3b417 51#include <linux/async.h>
bff61975 52#include <linux/seq_file.h>
36d1c647 53#include <linux/cpu.h>
5a0e3ad6 54#include <linux/slab.h>
8bda470e 55#include <linux/ratelimit.h>
851c30c9 56#include <linux/nodemask.h>
46d5b785 57#include <linux/flex_array.h>
3f07c014 58
a9add5d9 59#include <trace/events/block.h>
aaf9f12e 60#include <linux/list_sort.h>
a9add5d9 61
43b2e5d8 62#include "md.h"
bff61975 63#include "raid5.h"
54071b38 64#include "raid0.h"
935fe098 65#include "md-bitmap.h"
ff875738 66#include "raid5-log.h"
72626685 67
394ed8e4
SL		 68#define UNSUPPORTED_MDDEV_FLAGS (1L << MD_FAILFAST_SUPPORTED)
69
851c30c9
SL		 70#define cpu_to_group(cpu) cpu_to_node(cpu)
71#define ANY_GROUP NUMA_NO_NODE
72
8e0e99ba
N		 73static bool devices_handle_discard_safely = false;
74module_param(devices_handle_discard_safely, bool, 0644);
75MODULE_PARM_DESC(devices_handle_discard_safely,
76 "Set to Y if all devices in each array reliably return zeroes on reads from discarded regions");
851c30c9 77static struct workqueue_struct *raid5_wq;
1da177e4 78
d1688a6d 79static inline struct hlist_head *stripe_hash(struct r5conf *conf, sector_t sect)
db298e19
N		 80{
81 int hash = (sect >> STRIPE_SHIFT) & HASH_MASK;
82 return &conf->stripe_hashtbl[hash];
83}
1da177e4 84
566c09c5
SL		 85static inline int stripe_hash_locks_hash(sector_t sect)
86{
87 return (sect >> STRIPE_SHIFT) & STRIPE_HASH_LOCKS_MASK;
88}
89
90static inline void lock_device_hash_lock(struct r5conf *conf, int hash)
91{
92 spin_lock_irq(conf->hash_locks + hash);
93 spin_lock(&conf->device_lock);
94}
95
96static inline void unlock_device_hash_lock(struct r5conf *conf, int hash)
97{
98 spin_unlock(&conf->device_lock);
99 spin_unlock_irq(conf->hash_locks + hash);
100}
101
102static inline void lock_all_device_hash_locks_irq(struct r5conf *conf)
103{
104 int i;
3d05f3ae 105 spin_lock_irq(conf->hash_locks);
566c09c5
SL		 106 for (i = 1; i < NR_STRIPE_HASH_LOCKS; i++)
107 spin_lock_nest_lock(conf->hash_locks + i, conf->hash_locks);
108 spin_lock(&conf->device_lock);
109}
110
111static inline void unlock_all_device_hash_locks_irq(struct r5conf *conf)
112{
113 int i;
114 spin_unlock(&conf->device_lock);
3d05f3ae
JC		 115 for (i = NR_STRIPE_HASH_LOCKS - 1; i; i--)
116 spin_unlock(conf->hash_locks + i);
117 spin_unlock_irq(conf->hash_locks);
566c09c5
SL		 118}
119
d0dabf7e
N		 120/* Find first data disk in a raid6 stripe */
121static inline int raid6_d0(struct stripe_head *sh)
122{
67cc2b81
N		 123 if (sh->ddf_layout)
124 /* ddf always start from first device */
125 return 0;
126 /* md starts just after Q block */
d0dabf7e
N		 127 if (sh->qd_idx == sh->disks - 1)
128 return 0;
129 else
130 return sh->qd_idx + 1;
131}
16a53ecc
N		 132static inline int raid6_next_disk(int disk, int raid_disks)
133{
134 disk++;
135 return (disk < raid_disks) ? disk : 0;
136}
a4456856 137
d0dabf7e
N		 138/* When walking through the disks in a raid5, starting at raid6_d0,
139 * We need to map each disk to a 'slot', where the data disks are slot
140 * 0 .. raid_disks-3, the parity disk is raid_disks-2 and the Q disk
141 * is raid_disks-1. This help does that mapping.
142 */
67cc2b81
N		 143static int raid6_idx_to_slot(int idx, struct stripe_head *sh,
144 int *count, int syndrome_disks)
d0dabf7e 145{
6629542e 146 int slot = *count;
67cc2b81 147
e4424fee 148 if (sh->ddf_layout)
6629542e 149 (*count)++;
d0dabf7e 150 if (idx == sh->pd_idx)
67cc2b81 151 return syndrome_disks;
d0dabf7e 152 if (idx == sh->qd_idx)
67cc2b81 153 return syndrome_disks + 1;
e4424fee 154 if (!sh->ddf_layout)
6629542e 155 (*count)++;
d0dabf7e
N		 156 return slot;
157}
158
d1688a6d 159static void print_raid5_conf (struct r5conf *conf);
1da177e4 160
600aa109
DW		 161static int stripe_operations_active(struct stripe_head *sh)
162{
163 return sh->check_state || sh->reconstruct_state ||
164 test_bit(STRIPE_BIOFILL_RUN, &sh->state) ||
165 test_bit(STRIPE_COMPUTE_RUN, &sh->state);
166}
167
535ae4eb
SL		 168static bool stripe_is_lowprio(struct stripe_head *sh)
169{
170 return (test_bit(STRIPE_R5C_FULL_STRIPE, &sh->state) ||
171 test_bit(STRIPE_R5C_PARTIAL_STRIPE, &sh->state)) &&
172 !test_bit(STRIPE_R5C_CACHING, &sh->state);
173}
174
851c30c9
SL		 175static void raid5_wakeup_stripe_thread(struct stripe_head *sh)
176{
177 struct r5conf *conf = sh->raid_conf;
178 struct r5worker_group *group;
bfc90cb0 179 int thread_cnt;
851c30c9
SL		 180 int i, cpu = sh->cpu;
181
182 if (!cpu_online(cpu)) {
183 cpu = cpumask_any(cpu_online_mask);
184 sh->cpu = cpu;
185 }
186
187 if (list_empty(&sh->lru)) {
188 struct r5worker_group *group;
189 group = conf->worker_groups + cpu_to_group(cpu);
535ae4eb
SL		 190 if (stripe_is_lowprio(sh))
191 list_add_tail(&sh->lru, &group->loprio_list);
192 else
193 list_add_tail(&sh->lru, &group->handle_list);
bfc90cb0
SL		 194 group->stripes_cnt++;
195 sh->group = group;
851c30c9
SL		 196 }
197
198 if (conf->worker_cnt_per_group == 0) {
199 md_wakeup_thread(conf->mddev->thread);
200 return;
201 }
202
203 group = conf->worker_groups + cpu_to_group(sh->cpu);
204
bfc90cb0
SL		 205 group->workers[0].working = true;
206 /* at least one worker should run to avoid race */
207 queue_work_on(sh->cpu, raid5_wq, &group->workers[0].work);
208
209 thread_cnt = group->stripes_cnt / MAX_STRIPE_BATCH - 1;
210 /* wakeup more workers */
211 for (i = 1; i < conf->worker_cnt_per_group && thread_cnt > 0; i++) {
212 if (group->workers[i].working == false) {
213 group->workers[i].working = true;
214 queue_work_on(sh->cpu, raid5_wq,
215 &group->workers[i].work);
216 thread_cnt--;
217 }
218 }
851c30c9
SL		 219}
220
566c09c5
SL		 221static void do_release_stripe(struct r5conf *conf, struct stripe_head *sh,
222 struct list_head *temp_inactive_list)
1da177e4 223{
1e6d690b
SL		 224 int i;
225 int injournal = 0; /* number of date pages with R5_InJournal */
226
4eb788df
SL		 227 BUG_ON(!list_empty(&sh->lru));
228 BUG_ON(atomic_read(&conf->active_stripes)==0);
1e6d690b
SL		 229
230 if (r5c_is_writeback(conf->log))
231 for (i = sh->disks; i--; )
232 if (test_bit(R5_InJournal, &sh->dev[i].flags))
233 injournal++;
a39f7afd 234 /*
5ddf0440
SL		 235 * In the following cases, the stripe cannot be released to cached
236 * lists. Therefore, we make the stripe write out and set
237 * STRIPE_HANDLE:
238 * 1. when quiesce in r5c write back;
239 * 2. when resync is requested fot the stripe.
a39f7afd 240 */
5ddf0440
SL		 241 if (test_bit(STRIPE_SYNC_REQUESTED, &sh->state) ||
242 (conf->quiesce && r5c_is_writeback(conf->log) &&
243 !test_bit(STRIPE_HANDLE, &sh->state) && injournal != 0)) {
a39f7afd
SL		 244 if (test_bit(STRIPE_R5C_CACHING, &sh->state))
245 r5c_make_stripe_write_out(sh);
246 set_bit(STRIPE_HANDLE, &sh->state);
247 }
1e6d690b 248
4eb788df
SL		 249 if (test_bit(STRIPE_HANDLE, &sh->state)) {
250 if (test_bit(STRIPE_DELAYED, &sh->state) &&
ad3ab8b6 251 !test_bit(STRIPE_PREREAD_ACTIVE, &sh->state))
4eb788df 252 list_add_tail(&sh->lru, &conf->delayed_list);
ad3ab8b6 253 else if (test_bit(STRIPE_BIT_DELAY, &sh->state) &&
4eb788df
SL		 254 sh->bm_seq - conf->seq_write > 0)
255 list_add_tail(&sh->lru, &conf->bitmap_list);
256 else {
257 clear_bit(STRIPE_DELAYED, &sh->state);
258 clear_bit(STRIPE_BIT_DELAY, &sh->state);
851c30c9 259 if (conf->worker_cnt_per_group == 0) {
535ae4eb
SL		 260 if (stripe_is_lowprio(sh))
261 list_add_tail(&sh->lru,
262 &conf->loprio_list);
263 else
264 list_add_tail(&sh->lru,
265 &conf->handle_list);
851c30c9
SL		 266 } else {
267 raid5_wakeup_stripe_thread(sh);
268 return;
269 }
4eb788df
SL		 270 }
271 md_wakeup_thread(conf->mddev->thread);
272 } else {
273 BUG_ON(stripe_operations_active(sh));
274 if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE, &sh->state))
275 if (atomic_dec_return(&conf->preread_active_stripes)
276 < IO_THRESHOLD)
277 md_wakeup_thread(conf->mddev->thread);
278 atomic_dec(&conf->active_stripes);
1e6d690b
SL		 279 if (!test_bit(STRIPE_EXPANDING, &sh->state)) {
280 if (!r5c_is_writeback(conf->log))
281 list_add_tail(&sh->lru, temp_inactive_list);
282 else {
283 WARN_ON(test_bit(R5_InJournal, &sh->dev[sh->pd_idx].flags));
284 if (injournal == 0)
285 list_add_tail(&sh->lru, temp_inactive_list);
286 else if (injournal == conf->raid_disks - conf->max_degraded) {
287 /* full stripe */
288 if (!test_and_set_bit(STRIPE_R5C_FULL_STRIPE, &sh->state))
289 atomic_inc(&conf->r5c_cached_full_stripes);
290 if (test_and_clear_bit(STRIPE_R5C_PARTIAL_STRIPE, &sh->state))
291 atomic_dec(&conf->r5c_cached_partial_stripes);
292 list_add_tail(&sh->lru, &conf->r5c_full_stripe_list);
a39f7afd 293 r5c_check_cached_full_stripe(conf);
03b047f4
SL		 294 } else
295 /*
296 * STRIPE_R5C_PARTIAL_STRIPE is set in
297 * r5c_try_caching_write(). No need to
298 * set it again.
299 */
1e6d690b 300 list_add_tail(&sh->lru, &conf->r5c_partial_stripe_list);
1e6d690b
SL		 301 }
302 }
1da177e4
LT		 303 }
304}
d0dabf7e 305
566c09c5
SL		 306static void __release_stripe(struct r5conf *conf, struct stripe_head *sh,
307 struct list_head *temp_inactive_list)
4eb788df
SL		 308{
309 if (atomic_dec_and_test(&sh->count))
566c09c5
SL		 310 do_release_stripe(conf, sh, temp_inactive_list);
311}
312
313/*
314 * @hash could be NR_STRIPE_HASH_LOCKS, then we have a list of inactive_list
315 *
316 * Be careful: Only one task can add/delete stripes from temp_inactive_list at
317 * given time. Adding stripes only takes device lock, while deleting stripes
318 * only takes hash lock.
319 */
320static void release_inactive_stripe_list(struct r5conf *conf,
321 struct list_head *temp_inactive_list,
322 int hash)
323{
324 int size;
6ab2a4b8 325 bool do_wakeup = false;
566c09c5
SL		 326 unsigned long flags;
327
328 if (hash == NR_STRIPE_HASH_LOCKS) {
329 size = NR_STRIPE_HASH_LOCKS;
330 hash = NR_STRIPE_HASH_LOCKS - 1;
331 } else
332 size = 1;
333 while (size) {
334 struct list_head *list = &temp_inactive_list[size - 1];
335
336 /*
6d036f7d 337 * We don't hold any lock here yet, raid5_get_active_stripe() might
566c09c5
SL		 338 * remove stripes from the list
339 */
340 if (!list_empty_careful(list)) {
341 spin_lock_irqsave(conf->hash_locks + hash, flags);
4bda556a
SL		 342 if (list_empty(conf->inactive_list + hash) &&
343 !list_empty(list))
344 atomic_dec(&conf->empty_inactive_list_nr);
566c09c5 345 list_splice_tail_init(list, conf->inactive_list + hash);
6ab2a4b8 346 do_wakeup = true;
566c09c5
SL		 347 spin_unlock_irqrestore(conf->hash_locks + hash, flags);
348 }
349 size--;
350 hash--;
351 }
352
353 if (do_wakeup) {
6ab2a4b8 354 wake_up(&conf->wait_for_stripe);
b1b46486
YL		 355 if (atomic_read(&conf->active_stripes) == 0)
356 wake_up(&conf->wait_for_quiescent);
566c09c5
SL		 357 if (conf->retry_read_aligned)
358 md_wakeup_thread(conf->mddev->thread);
359 }
4eb788df
SL		 360}
361
773ca82f 362/* should hold conf->device_lock already */
566c09c5
SL		 363static int release_stripe_list(struct r5conf *conf,
364 struct list_head *temp_inactive_list)
773ca82f 365{
eae8263f 366 struct stripe_head *sh, *t;
773ca82f
SL		 367 int count = 0;
368 struct llist_node *head;
369
370 head = llist_del_all(&conf->released_stripes);
d265d9dc 371 head = llist_reverse_order(head);
eae8263f 372 llist_for_each_entry_safe(sh, t, head, release_list) {
566c09c5
SL		 373 int hash;
374
773ca82f
SL		 375 /* sh could be readded after STRIPE_ON_RELEASE_LIST is cleard */
376 smp_mb();
377 clear_bit(STRIPE_ON_RELEASE_LIST, &sh->state);
378 /*
379 * Don't worry the bit is set here, because if the bit is set
380 * again, the count is always > 1. This is true for
381 * STRIPE_ON_UNPLUG_LIST bit too.
382 */
566c09c5
SL		 383 hash = sh->hash_lock_index;
384 __release_stripe(conf, sh, &temp_inactive_list[hash]);
773ca82f
SL		 385 count++;
386 }
387
388 return count;
389}
390
6d036f7d 391void raid5_release_stripe(struct stripe_head *sh)
1da177e4 392{
d1688a6d 393 struct r5conf *conf = sh->raid_conf;
1da177e4 394 unsigned long flags;
566c09c5
SL		 395 struct list_head list;
396 int hash;
773ca82f 397 bool wakeup;
16a53ecc 398
cf170f3f
ES		 399 /* Avoid release_list until the last reference.
400 */
401 if (atomic_add_unless(&sh->count, -1, 1))
402 return;
403
ad4068de 404 if (unlikely(!conf->mddev->thread) ||
405 test_and_set_bit(STRIPE_ON_RELEASE_LIST, &sh->state))
773ca82f
SL		 406 goto slow_path;
407 wakeup = llist_add(&sh->release_list, &conf->released_stripes);
408 if (wakeup)
409 md_wakeup_thread(conf->mddev->thread);
410 return;
411slow_path:
4eb788df 412 local_irq_save(flags);
773ca82f 413 /* we are ok here if STRIPE_ON_RELEASE_LIST is set or not */
4eb788df 414 if (atomic_dec_and_lock(&sh->count, &conf->device_lock)) {
566c09c5
SL		 415 INIT_LIST_HEAD(&list);
416 hash = sh->hash_lock_index;
417 do_release_stripe(conf, sh, &list);
4eb788df 418 spin_unlock(&conf->device_lock);
566c09c5 419 release_inactive_stripe_list(conf, &list, hash);
4eb788df
SL		 420 }
421 local_irq_restore(flags);
1da177e4
LT		 422}
423
fccddba0 424static inline void remove_hash(struct stripe_head *sh)
1da177e4 425{
45b4233c
DW		 426 pr_debug("remove_hash(), stripe %llu\n",
427 (unsigned long long)sh->sector);
1da177e4 428
fccddba0 429 hlist_del_init(&sh->hash);
1da177e4
LT		 430}
431
d1688a6d 432static inline void insert_hash(struct r5conf *conf, struct stripe_head *sh)
1da177e4 433{
fccddba0 434 struct hlist_head *hp = stripe_hash(conf, sh->sector);
1da177e4 435
45b4233c
DW		 436 pr_debug("insert_hash(), stripe %llu\n",
437 (unsigned long long)sh->sector);
1da177e4 438
fccddba0 439 hlist_add_head(&sh->hash, hp);
1da177e4
LT		 440}
441
1da177e4 442/* find an idle stripe, make sure it is unhashed, and return it. */
566c09c5 443static struct stripe_head *get_free_stripe(struct r5conf *conf, int hash)
1da177e4
LT		 444{
445 struct stripe_head *sh = NULL;
446 struct list_head *first;
447
566c09c5 448 if (list_empty(conf->inactive_list + hash))
1da177e4 449 goto out;
566c09c5 450 first = (conf->inactive_list + hash)->next;
1da177e4
LT		 451 sh = list_entry(first, struct stripe_head, lru);
452 list_del_init(first);
453 remove_hash(sh);
454 atomic_inc(&conf->active_stripes);
566c09c5 455 BUG_ON(hash != sh->hash_lock_index);
4bda556a
SL		 456 if (list_empty(conf->inactive_list + hash))
457 atomic_inc(&conf->empty_inactive_list_nr);
1da177e4
LT		 458out:
459 return sh;
460}
461
e4e11e38 462static void shrink_buffers(struct stripe_head *sh)
1da177e4
LT		 463{
464 struct page *p;
465 int i;
e4e11e38 466 int num = sh->raid_conf->pool_size;
1da177e4 467
e4e11e38 468 for (i = 0; i < num ; i++) {
d592a996 469 WARN_ON(sh->dev[i].page != sh->dev[i].orig_page);
1da177e4
LT		 470 p = sh->dev[i].page;
471 if (!p)
472 continue;
473 sh->dev[i].page = NULL;
2d1f3b5d 474 put_page(p);
1da177e4
LT		 475 }
476}
477
a9683a79 478static int grow_buffers(struct stripe_head *sh, gfp_t gfp)
1da177e4
LT		 479{
480 int i;
e4e11e38 481 int num = sh->raid_conf->pool_size;
1da177e4 482
e4e11e38 483 for (i = 0; i < num; i++) {
1da177e4
LT		 484 struct page *page;
485
a9683a79 486 if (!(page = alloc_page(gfp))) {
1da177e4
LT		 487 return 1;
488 }
489 sh->dev[i].page = page;
d592a996 490 sh->dev[i].orig_page = page;
1da177e4 491 }
3418d036 492
1da177e4
LT		 493 return 0;
494}
495
d1688a6d 496static void stripe_set_idx(sector_t stripe, struct r5conf *conf, int previous,
911d4ee8 497 struct stripe_head *sh);
1da177e4 498
b5663ba4 499static void init_stripe(struct stripe_head *sh, sector_t sector, int previous)
1da177e4 500{
d1688a6d 501 struct r5conf *conf = sh->raid_conf;
566c09c5 502 int i, seq;
1da177e4 503
78bafebd
ES		 504 BUG_ON(atomic_read(&sh->count) != 0);
505 BUG_ON(test_bit(STRIPE_HANDLE, &sh->state));
600aa109 506 BUG_ON(stripe_operations_active(sh));
59fc630b 507 BUG_ON(sh->batch_head);
d84e0f10 508
45b4233c 509 pr_debug("init_stripe called, stripe %llu\n",
b8e6a15a 510 (unsigned long long)sector);
566c09c5
SL		 511retry:
512 seq = read_seqcount_begin(&conf->gen_lock);
86b42c71 513 sh->generation = conf->generation - previous;
b5663ba4 514 sh->disks = previous ? conf->previous_raid_disks : conf->raid_disks;
1da177e4 515 sh->sector = sector;
911d4ee8 516 stripe_set_idx(sector, conf, previous, sh);
1da177e4
LT		 517 sh->state = 0;
518
7ecaa1e6 519 for (i = sh->disks; i--; ) {
1da177e4
LT		 520 struct r5dev *dev = &sh->dev[i];
521
d84e0f10 522 if (dev->toread || dev->read || dev->towrite || dev->written ||
1da177e4 523 test_bit(R5_LOCKED, &dev->flags)) {
cc6167b4 524 pr_err("sector=%llx i=%d %p %p %p %p %d\n",
1da177e4 525 (unsigned long long)sh->sector, i, dev->toread,
d84e0f10 526 dev->read, dev->towrite, dev->written,
1da177e4 527 test_bit(R5_LOCKED, &dev->flags));
8cfa7b0f 528 WARN_ON(1);
1da177e4
LT		 529 }
530 dev->flags = 0;
27a4ff8f 531 dev->sector = raid5_compute_blocknr(sh, i, previous);
1da177e4 532 }
566c09c5
SL		 533 if (read_seqcount_retry(&conf->gen_lock, seq))
534 goto retry;
7a87f434 535 sh->overwrite_disks = 0;
1da177e4 536 insert_hash(conf, sh);
851c30c9 537 sh->cpu = smp_processor_id();
da41ba65 538 set_bit(STRIPE_BATCH_READY, &sh->state);
1da177e4
LT		 539}
540
d1688a6d 541static struct stripe_head *__find_stripe(struct r5conf *conf, sector_t sector,
86b42c71 542 short generation)
1da177e4
LT		 543{
544 struct stripe_head *sh;
545
45b4233c 546 pr_debug("__find_stripe, sector %llu\n", (unsigned long long)sector);
b67bfe0d 547 hlist_for_each_entry(sh, stripe_hash(conf, sector), hash)
86b42c71 548 if (sh->sector == sector && sh->generation == generation)
1da177e4 549 return sh;
45b4233c 550 pr_debug("__stripe %llu not in cache\n", (unsigned long long)sector);
1da177e4
LT		 551 return NULL;
552}
553
674806d6
N		 554/*
555 * Need to check if array has failed when deciding whether to:
556 * - start an array
557 * - remove non-faulty devices
558 * - add a spare
559 * - allow a reshape
560 * This determination is simple when no reshape is happening.
561 * However if there is a reshape, we need to carefully check
562 * both the before and after sections.
563 * This is because some failed devices may only affect one
564 * of the two sections, and some non-in_sync devices may
565 * be insync in the section most affected by failed devices.
566 */
2e38a37f 567int raid5_calc_degraded(struct r5conf *conf)
674806d6 568{
908f4fbd 569 int degraded, degraded2;
674806d6 570 int i;
674806d6
N		 571
572 rcu_read_lock();
573 degraded = 0;
574 for (i = 0; i < conf->previous_raid_disks; i++) {
3cb03002 575 struct md_rdev *rdev = rcu_dereference(conf->disks[i].rdev);
e5c86471
N		 576 if (rdev && test_bit(Faulty, &rdev->flags))
577 rdev = rcu_dereference(conf->disks[i].replacement);
674806d6
N		 578 if (!rdev || test_bit(Faulty, &rdev->flags))
579 degraded++;
580 else if (test_bit(In_sync, &rdev->flags))
581 ;
582 else
583 /* not in-sync or faulty.
584 * If the reshape increases the number of devices,
585 * this is being recovered by the reshape, so
586 * this 'previous' section is not in_sync.
587 * If the number of devices is being reduced however,
588 * the device can only be part of the array if
589 * we are reverting a reshape, so this section will
590 * be in-sync.
591 */
592 if (conf->raid_disks >= conf->previous_raid_disks)
593 degraded++;
594 }
595 rcu_read_unlock();
908f4fbd
N		 596 if (conf->raid_disks == conf->previous_raid_disks)
597 return degraded;
674806d6 598 rcu_read_lock();
908f4fbd 599 degraded2 = 0;
674806d6 600 for (i = 0; i < conf->raid_disks; i++) {
3cb03002 601 struct md_rdev *rdev = rcu_dereference(conf->disks[i].rdev);
e5c86471
N		 602 if (rdev && test_bit(Faulty, &rdev->flags))
603 rdev = rcu_dereference(conf->disks[i].replacement);
674806d6 604 if (!rdev || test_bit(Faulty, &rdev->flags))
908f4fbd 605 degraded2++;
674806d6
N		 606 else if (test_bit(In_sync, &rdev->flags))
607 ;
608 else
609 /* not in-sync or faulty.
610 * If reshape increases the number of devices, this
611 * section has already been recovered, else it
612 * almost certainly hasn't.
613 */
614 if (conf->raid_disks <= conf->previous_raid_disks)
908f4fbd 615 degraded2++;
674806d6
N		 616 }
617 rcu_read_unlock();
908f4fbd
N		 618 if (degraded2 > degraded)
619 return degraded2;
620 return degraded;
621}
622
623static int has_failed(struct r5conf *conf)
624{
625 int degraded;
626
627 if (conf->mddev->reshape_position == MaxSector)
628 return conf->mddev->degraded > conf->max_degraded;
629
2e38a37f 630 degraded = raid5_calc_degraded(conf);
674806d6
N		 631 if (degraded > conf->max_degraded)
632 return 1;
633 return 0;
634}
635
6d036f7d
SL		 636struct stripe_head *
637raid5_get_active_stripe(struct r5conf *conf, sector_t sector,
638 int previous, int noblock, int noquiesce)
1da177e4
LT		 639{
640 struct stripe_head *sh;
566c09c5 641 int hash = stripe_hash_locks_hash(sector);
ff00d3b4 642 int inc_empty_inactive_list_flag;
1da177e4 643
45b4233c 644 pr_debug("get_stripe, sector %llu\n", (unsigned long long)sector);
1da177e4 645
566c09c5 646 spin_lock_irq(conf->hash_locks + hash);
1da177e4
LT		 647
648 do {
b1b46486 649 wait_event_lock_irq(conf->wait_for_quiescent,
a8c906ca 650 conf->quiesce == 0 || noquiesce,
566c09c5 651 *(conf->hash_locks + hash));
86b42c71 652 sh = __find_stripe(conf, sector, conf->generation - previous);
1da177e4 653 if (!sh) {
edbe83ab 654 if (!test_bit(R5_INACTIVE_BLOCKED, &conf->cache_state)) {
566c09c5 655 sh = get_free_stripe(conf, hash);
713bc5c2
SL		 656 if (!sh && !test_bit(R5_DID_ALLOC,
657 &conf->cache_state))
edbe83ab
N		 658 set_bit(R5_ALLOC_MORE,
659 &conf->cache_state);
660 }
1da177e4
LT		 661 if (noblock && sh == NULL)
662 break;
a39f7afd
SL		 663
664 r5c_check_stripe_cache_usage(conf);
1da177e4 665 if (!sh) {
5423399a
N		 666 set_bit(R5_INACTIVE_BLOCKED,
667 &conf->cache_state);
a39f7afd 668 r5l_wake_reclaim(conf->log, 0);
6ab2a4b8
SL		 669 wait_event_lock_irq(
670 conf->wait_for_stripe,
566c09c5
SL		 671 !list_empty(conf->inactive_list + hash) &&
672 (atomic_read(&conf->active_stripes)
673 < (conf->max_nr_stripes * 3 / 4)
5423399a
N		 674 || !test_bit(R5_INACTIVE_BLOCKED,
675 &conf->cache_state)),
6ab2a4b8 676 *(conf->hash_locks + hash));
5423399a
N		 677 clear_bit(R5_INACTIVE_BLOCKED,
678 &conf->cache_state);
7da9d450 679 } else {
b5663ba4 680 init_stripe(sh, sector, previous);
7da9d450
N		 681 atomic_inc(&sh->count);
682 }
e240c183 683 } else if (!atomic_inc_not_zero(&sh->count)) {
6d183de4 684 spin_lock(&conf->device_lock);
e240c183 685 if (!atomic_read(&sh->count)) {
1da177e4
LT		 686 if (!test_bit(STRIPE_HANDLE, &sh->state))
687 atomic_inc(&conf->active_stripes);
5af9bef7
N		 688 BUG_ON(list_empty(&sh->lru) &&
689 !test_bit(STRIPE_EXPANDING, &sh->state));
ff00d3b4
ZL		 690 inc_empty_inactive_list_flag = 0;
691 if (!list_empty(conf->inactive_list + hash))
692 inc_empty_inactive_list_flag = 1;
16a53ecc 693 list_del_init(&sh->lru);
ff00d3b4
ZL		 694 if (list_empty(conf->inactive_list + hash) && inc_empty_inactive_list_flag)
695 atomic_inc(&conf->empty_inactive_list_nr);
bfc90cb0
SL		 696 if (sh->group) {
697 sh->group->stripes_cnt--;
698 sh->group = NULL;
699 }
1da177e4 700 }
7da9d450 701 atomic_inc(&sh->count);
6d183de4 702 spin_unlock(&conf->device_lock);
1da177e4
LT		 703 }
704 } while (sh == NULL);
705
566c09c5 706 spin_unlock_irq(conf->hash_locks + hash);
1da177e4
LT		 707 return sh;
708}
709
7a87f434 710static bool is_full_stripe_write(struct stripe_head *sh)
711{
712 BUG_ON(sh->overwrite_disks > (sh->disks - sh->raid_conf->max_degraded));
713 return sh->overwrite_disks == (sh->disks - sh->raid_conf->max_degraded);
714}
715
59fc630b 716static void lock_two_stripes(struct stripe_head *sh1, struct stripe_head *sh2)
717{
59fc630b 718 if (sh1 > sh2) {
3d05f3ae 719 spin_lock_irq(&sh2->stripe_lock);
59fc630b 720 spin_lock_nested(&sh1->stripe_lock, 1);
721 } else {
3d05f3ae 722 spin_lock_irq(&sh1->stripe_lock);
59fc630b 723 spin_lock_nested(&sh2->stripe_lock, 1);
724 }
725}
726
727static void unlock_two_stripes(struct stripe_head *sh1, struct stripe_head *sh2)
728{
729 spin_unlock(&sh1->stripe_lock);
3d05f3ae 730 spin_unlock_irq(&sh2->stripe_lock);
59fc630b 731}
732
733/* Only freshly new full stripe normal write stripe can be added to a batch list */
734static bool stripe_can_batch(struct stripe_head *sh)
735{
9c3e333d
SL		 736 struct r5conf *conf = sh->raid_conf;
737
3418d036 738 if (conf->log || raid5_has_ppl(conf))
9c3e333d 739 return false;
59fc630b 740 return test_bit(STRIPE_BATCH_READY, &sh->state) &&
d0852df5 741 !test_bit(STRIPE_BITMAP_PENDING, &sh->state) &&
59fc630b 742 is_full_stripe_write(sh);
743}
744
745/* we only do back search */
746static void stripe_add_to_batch_list(struct r5conf *conf, struct stripe_head *sh)
747{
748 struct stripe_head *head;
749 sector_t head_sector, tmp_sec;
750 int hash;
751 int dd_idx;
ff00d3b4 752 int inc_empty_inactive_list_flag;
59fc630b 753
59fc630b 754 /* Don't cross chunks, so stripe pd_idx/qd_idx is the same */
755 tmp_sec = sh->sector;
756 if (!sector_div(tmp_sec, conf->chunk_sectors))
757 return;
758 head_sector = sh->sector - STRIPE_SECTORS;
759
760 hash = stripe_hash_locks_hash(head_sector);
761 spin_lock_irq(conf->hash_locks + hash);
762 head = __find_stripe(conf, head_sector, conf->generation);
763 if (head && !atomic_inc_not_zero(&head->count)) {
764 spin_lock(&conf->device_lock);
765 if (!atomic_read(&head->count)) {
766 if (!test_bit(STRIPE_HANDLE, &head->state))
767 atomic_inc(&conf->active_stripes);
768 BUG_ON(list_empty(&head->lru) &&
769 !test_bit(STRIPE_EXPANDING, &head->state));
ff00d3b4
ZL		 770 inc_empty_inactive_list_flag = 0;
771 if (!list_empty(conf->inactive_list + hash))
772 inc_empty_inactive_list_flag = 1;
59fc630b 773 list_del_init(&head->lru);
ff00d3b4
ZL		 774 if (list_empty(conf->inactive_list + hash) && inc_empty_inactive_list_flag)
775 atomic_inc(&conf->empty_inactive_list_nr);
59fc630b 776 if (head->group) {
777 head->group->stripes_cnt--;
778 head->group = NULL;
779 }
780 }
781 atomic_inc(&head->count);
782 spin_unlock(&conf->device_lock);
783 }
784 spin_unlock_irq(conf->hash_locks + hash);
785
786 if (!head)
787 return;
788 if (!stripe_can_batch(head))
789 goto out;
790
791 lock_two_stripes(head, sh);
792 /* clear_batch_ready clear the flag */
793 if (!stripe_can_batch(head) || !stripe_can_batch(sh))
794 goto unlock_out;
795
796 if (sh->batch_head)
797 goto unlock_out;
798
799 dd_idx = 0;
800 while (dd_idx == sh->pd_idx || dd_idx == sh->qd_idx)
801 dd_idx++;
1eff9d32 802 if (head->dev[dd_idx].towrite->bi_opf != sh->dev[dd_idx].towrite->bi_opf ||
796a5cf0 803 bio_op(head->dev[dd_idx].towrite) != bio_op(sh->dev[dd_idx].towrite))
59fc630b 804 goto unlock_out;
805
806 if (head->batch_head) {
807 spin_lock(&head->batch_head->batch_lock);
808 /* This batch list is already running */
809 if (!stripe_can_batch(head)) {
810 spin_unlock(&head->batch_head->batch_lock);
811 goto unlock_out;
812 }
3664847d
SL		 813 /*
814 * We must assign batch_head of this stripe within the
815 * batch_lock, otherwise clear_batch_ready of batch head
816 * stripe could clear BATCH_READY bit of this stripe and
817 * this stripe->batch_head doesn't get assigned, which
818 * could confuse clear_batch_ready for this stripe
819 */
820 sh->batch_head = head->batch_head;
59fc630b 821
822 /*
823 * at this point, head's BATCH_READY could be cleared, but we
824 * can still add the stripe to batch list
825 */
826 list_add(&sh->batch_list, &head->batch_list);
827 spin_unlock(&head->batch_head->batch_lock);
59fc630b 828 } else {
829 head->batch_head = head;
830 sh->batch_head = head->batch_head;
831 spin_lock(&head->batch_lock);
832 list_add_tail(&sh->batch_list, &head->batch_list);
833 spin_unlock(&head->batch_lock);
834 }
835
836 if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE, &sh->state))
837 if (atomic_dec_return(&conf->preread_active_stripes)
838 < IO_THRESHOLD)
839 md_wakeup_thread(conf->mddev->thread);
840
2b6b2457
N		 841 if (test_and_clear_bit(STRIPE_BIT_DELAY, &sh->state)) {
842 int seq = sh->bm_seq;
843 if (test_bit(STRIPE_BIT_DELAY, &sh->batch_head->state) &&
844 sh->batch_head->bm_seq > seq)
845 seq = sh->batch_head->bm_seq;
846 set_bit(STRIPE_BIT_DELAY, &sh->batch_head->state);
847 sh->batch_head->bm_seq = seq;
848 }
849
59fc630b 850 atomic_inc(&sh->count);
851unlock_out:
852 unlock_two_stripes(head, sh);
853out:
6d036f7d 854 raid5_release_stripe(head);
59fc630b 855}
856
05616be5
N		 857/* Determine if 'data_offset' or 'new_data_offset' should be used
858 * in this stripe_head.
859 */
860static int use_new_offset(struct r5conf *conf, struct stripe_head *sh)
861{
862 sector_t progress = conf->reshape_progress;
863 /* Need a memory barrier to make sure we see the value
864 * of conf->generation, or ->data_offset that was set before
865 * reshape_progress was updated.
866 */
867 smp_rmb();
868 if (progress == MaxSector)
869 return 0;
870 if (sh->generation == conf->generation - 1)
871 return 0;
872 /* We are in a reshape, and this is a new-generation stripe,
873 * so use new_data_offset.
874 */
875 return 1;
876}
877
aaf9f12e 878static void dispatch_bio_list(struct bio_list *tmp)
765d704d 879{
765d704d
SL		 880 struct bio *bio;
881
aaf9f12e
SL		 882 while ((bio = bio_list_pop(tmp)))
883 generic_make_request(bio);
884}
885
886static int cmp_stripe(void *priv, struct list_head *a, struct list_head *b)
887{
888 const struct r5pending_data *da = list_entry(a,
889 struct r5pending_data, sibling);
890 const struct r5pending_data *db = list_entry(b,
891 struct r5pending_data, sibling);
892 if (da->sector > db->sector)
893 return 1;
894 if (da->sector < db->sector)
895 return -1;
896 return 0;
897}
898
899static void dispatch_defer_bios(struct r5conf *conf, int target,
900 struct bio_list *list)
901{
902 struct r5pending_data *data;
903 struct list_head *first, *next = NULL;
904 int cnt = 0;
905
906 if (conf->pending_data_cnt == 0)
907 return;
908
909 list_sort(NULL, &conf->pending_list, cmp_stripe);
910
911 first = conf->pending_list.next;
912
913 /* temporarily move the head */
914 if (conf->next_pending_data)
915 list_move_tail(&conf->pending_list,
916 &conf->next_pending_data->sibling);
917
918 while (!list_empty(&conf->pending_list)) {
919 data = list_first_entry(&conf->pending_list,
920 struct r5pending_data, sibling);
921 if (&data->sibling == first)
922 first = data->sibling.next;
923 next = data->sibling.next;
924
925 bio_list_merge(list, &data->bios);
926 list_move(&data->sibling, &conf->free_list);
927 cnt++;
928 if (cnt >= target)
929 break;
930 }
931 conf->pending_data_cnt -= cnt;
932 BUG_ON(conf->pending_data_cnt < 0 || cnt < target);
933
934 if (next != &conf->pending_list)
935 conf->next_pending_data = list_entry(next,
936 struct r5pending_data, sibling);
937 else
938 conf->next_pending_data = NULL;
939 /* list isn't empty */
940 if (first != &conf->pending_list)
941 list_move_tail(&conf->pending_list, first);
942}
943
944static void flush_deferred_bios(struct r5conf *conf)
945{
946 struct bio_list tmp = BIO_EMPTY_LIST;
947
948 if (conf->pending_data_cnt == 0)
765d704d
SL		 949 return;
950
765d704d 951 spin_lock(&conf->pending_bios_lock);
aaf9f12e
SL		 952 dispatch_defer_bios(conf, conf->pending_data_cnt, &tmp);
953 BUG_ON(conf->pending_data_cnt != 0);
765d704d
SL		 954 spin_unlock(&conf->pending_bios_lock);
955
aaf9f12e 956 dispatch_bio_list(&tmp);
765d704d
SL		 957}
958
aaf9f12e
SL		 959static void defer_issue_bios(struct r5conf *conf, sector_t sector,
960 struct bio_list *bios)
765d704d 961{
aaf9f12e
SL		 962 struct bio_list tmp = BIO_EMPTY_LIST;
963 struct r5pending_data *ent;
964
765d704d 965 spin_lock(&conf->pending_bios_lock);
aaf9f12e
SL		 966 ent = list_first_entry(&conf->free_list, struct r5pending_data,
967 sibling);
968 list_move_tail(&ent->sibling, &conf->pending_list);
969 ent->sector = sector;
970 bio_list_init(&ent->bios);
971 bio_list_merge(&ent->bios, bios);
972 conf->pending_data_cnt++;
973 if (conf->pending_data_cnt >= PENDING_IO_MAX)
974 dispatch_defer_bios(conf, PENDING_IO_ONE_FLUSH, &tmp);
975
765d704d 976 spin_unlock(&conf->pending_bios_lock);
aaf9f12e
SL		 977
978 dispatch_bio_list(&tmp);
765d704d
SL		 979}
980
6712ecf8 981static void
4246a0b6 982raid5_end_read_request(struct bio *bi);
6712ecf8 983static void
4246a0b6 984raid5_end_write_request(struct bio *bi);
91c00924 985
c4e5ac0a 986static void ops_run_io(struct stripe_head *sh, struct stripe_head_state *s)
91c00924 987{
d1688a6d 988 struct r5conf *conf = sh->raid_conf;
91c00924 989 int i, disks = sh->disks;
59fc630b 990 struct stripe_head *head_sh = sh;
aaf9f12e
SL		 991 struct bio_list pending_bios = BIO_EMPTY_LIST;
992 bool should_defer;
91c00924
DW		 993
994 might_sleep();
995
ff875738
AP		 996 if (log_stripe(sh, s) == 0)
997 return;
1e6d690b 998
aaf9f12e 999 should_defer = conf->batch_bio_dispatch && conf->group_cnt;
1e6d690b 1000
91c00924 1001 for (i = disks; i--; ) {
796a5cf0 1002 int op, op_flags = 0;
9a3e1101 1003 int replace_only = 0;
977df362
N		 1004 struct bio *bi, *rbi;
1005 struct md_rdev *rdev, *rrdev = NULL;
59fc630b 1006
1007 sh = head_sh;
e9c7469b 1008 if (test_and_clear_bit(R5_Wantwrite, &sh->dev[i].flags)) {
796a5cf0 1009 op = REQ_OP_WRITE;
e9c7469b 1010 if (test_and_clear_bit(R5_WantFUA, &sh->dev[i].flags))
70fd7614 1011 op_flags = REQ_FUA;
9e444768 1012 if (test_bit(R5_Discard, &sh->dev[i].flags))
796a5cf0 1013 op = REQ_OP_DISCARD;
e9c7469b 1014 } else if (test_and_clear_bit(R5_Wantread, &sh->dev[i].flags))
796a5cf0 1015 op = REQ_OP_READ;
9a3e1101
N		 1016 else if (test_and_clear_bit(R5_WantReplace,
1017 &sh->dev[i].flags)) {
796a5cf0 1018 op = REQ_OP_WRITE;
9a3e1101
N		 1019 replace_only = 1;
1020 } else
91c00924 1021 continue;
bc0934f0 1022 if (test_and_clear_bit(R5_SyncIO, &sh->dev[i].flags))
796a5cf0 1023 op_flags |= REQ_SYNC;
91c00924 1024
59fc630b 1025again:
91c00924 1026 bi = &sh->dev[i].req;
977df362 1027 rbi = &sh->dev[i].rreq; /* For writing to replacement */
91c00924 1028
91c00924 1029 rcu_read_lock();
9a3e1101 1030 rrdev = rcu_dereference(conf->disks[i].replacement);
dd054fce
N		 1031 smp_mb(); /* Ensure that if rrdev is NULL, rdev won't be */
1032 rdev = rcu_dereference(conf->disks[i].rdev);
1033 if (!rdev) {
1034 rdev = rrdev;
1035 rrdev = NULL;
1036 }
796a5cf0 1037 if (op_is_write(op)) {
9a3e1101
N		 1038 if (replace_only)
1039 rdev = NULL;
dd054fce
N		 1040 if (rdev == rrdev)
1041 /* We raced and saw duplicates */
1042 rrdev = NULL;
9a3e1101 1043 } else {
59fc630b 1044 if (test_bit(R5_ReadRepl, &head_sh->dev[i].flags) && rrdev)
9a3e1101
N		 1045 rdev = rrdev;
1046 rrdev = NULL;
1047 }
977df362 1048
91c00924
DW		 1049 if (rdev && test_bit(Faulty, &rdev->flags))
1050 rdev = NULL;
1051 if (rdev)
1052 atomic_inc(&rdev->nr_pending);
977df362
N		 1053 if (rrdev && test_bit(Faulty, &rrdev->flags))
1054 rrdev = NULL;
1055 if (rrdev)
1056 atomic_inc(&rrdev->nr_pending);
91c00924
DW		 1057 rcu_read_unlock();
1058
73e92e51 1059 /* We have already checked bad blocks for reads. Now
977df362
N		 1060 * need to check for writes. We never accept write errors
1061 * on the replacement, so we don't to check rrdev.
73e92e51 1062 */
796a5cf0 1063 while (op_is_write(op) && rdev &&
73e92e51
N		 1064 test_bit(WriteErrorSeen, &rdev->flags)) {
1065 sector_t first_bad;
1066 int bad_sectors;
1067 int bad = is_badblock(rdev, sh->sector, STRIPE_SECTORS,
1068 &first_bad, &bad_sectors);
1069 if (!bad)
1070 break;
1071
1072 if (bad < 0) {
1073 set_bit(BlockedBadBlocks, &rdev->flags);
1074 if (!conf->mddev->external &&
2953079c 1075 conf->mddev->sb_flags) {
73e92e51
N		 1076 /* It is very unlikely, but we might
1077 * still need to write out the
1078 * bad block log - better give it
1079 * a chance*/
1080 md_check_recovery(conf->mddev);
1081 }
1850753d 1082 /*
1083 * Because md_wait_for_blocked_rdev
1084 * will dec nr_pending, we must
1085 * increment it first.
1086 */
1087 atomic_inc(&rdev->nr_pending);
73e92e51
N		 1088 md_wait_for_blocked_rdev(rdev, conf->mddev);
1089 } else {
1090 /* Acknowledged bad block - skip the write */
1091 rdev_dec_pending(rdev, conf->mddev);
1092 rdev = NULL;
1093 }
1094 }
1095
91c00924 1096 if (rdev) {
9a3e1101
N		 1097 if (s->syncing || s->expanding || s->expanded
1098 || s->replacing)
91c00924
DW		 1099 md_sync_acct(rdev->bdev, STRIPE_SECTORS);
1100
2b7497f0
DW		 1101 set_bit(STRIPE_IO_STARTED, &sh->state);
1102
74d46992 1103 bio_set_dev(bi, rdev->bdev);
796a5cf0
MC		 1104 bio_set_op_attrs(bi, op, op_flags);
1105 bi->bi_end_io = op_is_write(op)
2f6db2a7
KO		 1106 ? raid5_end_write_request
1107 : raid5_end_read_request;
1108 bi->bi_private = sh;
1109
6296b960 1110 pr_debug("%s: for %llu schedule op %d on disc %d\n",
e46b272b 1111 __func__, (unsigned long long)sh->sector,
1eff9d32 1112 bi->bi_opf, i);
91c00924 1113 atomic_inc(&sh->count);
59fc630b 1114 if (sh != head_sh)
1115 atomic_inc(&head_sh->count);
05616be5 1116 if (use_new_offset(conf, sh))
4f024f37 1117 bi->bi_iter.bi_sector = (sh->sector
05616be5
N		 1118 + rdev->new_data_offset);
1119 else
4f024f37 1120 bi->bi_iter.bi_sector = (sh->sector
05616be5 1121 + rdev->data_offset);
59fc630b 1122 if (test_bit(R5_ReadNoMerge, &head_sh->dev[i].flags))
1eff9d32 1123 bi->bi_opf |= REQ_NOMERGE;
3f9e7c14 1124
d592a996
SL		 1125 if (test_bit(R5_SkipCopy, &sh->dev[i].flags))
1126 WARN_ON(test_bit(R5_UPTODATE, &sh->dev[i].flags));
86aa1397
SL		 1127
1128 if (!op_is_write(op) &&
1129 test_bit(R5_InJournal, &sh->dev[i].flags))
1130 /*
1131 * issuing read for a page in journal, this
1132 * must be preparing for prexor in rmw; read
1133 * the data into orig_page
1134 */
1135 sh->dev[i].vec.bv_page = sh->dev[i].orig_page;
1136 else
1137 sh->dev[i].vec.bv_page = sh->dev[i].page;
4997b72e 1138 bi->bi_vcnt = 1;
91c00924
DW		 1139 bi->bi_io_vec[0].bv_len = STRIPE_SIZE;
1140 bi->bi_io_vec[0].bv_offset = 0;
4f024f37 1141 bi->bi_iter.bi_size = STRIPE_SIZE;
2cd259a7
MD		 1142 bi->bi_write_hint = sh->dev[i].write_hint;
1143 if (!rrdev)
1144 sh->dev[i].write_hint = RWF_WRITE_LIFE_NOT_SET;
37c61ff3
SL		 1145 /*
1146 * If this is discard request, set bi_vcnt 0. We don't
1147 * want to confuse SCSI because SCSI will replace payload
1148 */
796a5cf0 1149 if (op == REQ_OP_DISCARD)
37c61ff3 1150 bi->bi_vcnt = 0;
977df362
N		 1151 if (rrdev)
1152 set_bit(R5_DOUBLE_LOCKED, &sh->dev[i].flags);
e3620a3a
JB		 1153
1154 if (conf->mddev->gendisk)
74d46992 1155 trace_block_bio_remap(bi->bi_disk->queue,
e3620a3a
JB		 1156 bi, disk_devt(conf->mddev->gendisk),
1157 sh->dev[i].sector);
aaf9f12e
SL		 1158 if (should_defer && op_is_write(op))
1159 bio_list_add(&pending_bios, bi);
1160 else
1161 generic_make_request(bi);
977df362
N		 1162 }
1163 if (rrdev) {
9a3e1101
N		 1164 if (s->syncing || s->expanding || s->expanded
1165 || s->replacing)
977df362
N		 1166 md_sync_acct(rrdev->bdev, STRIPE_SECTORS);
1167
1168 set_bit(STRIPE_IO_STARTED, &sh->state);
1169
74d46992 1170 bio_set_dev(rbi, rrdev->bdev);
796a5cf0
MC		 1171 bio_set_op_attrs(rbi, op, op_flags);
1172 BUG_ON(!op_is_write(op));
2f6db2a7
KO		 1173 rbi->bi_end_io = raid5_end_write_request;
1174 rbi->bi_private = sh;
1175
6296b960 1176 pr_debug("%s: for %llu schedule op %d on "
977df362
N		 1177 "replacement disc %d\n",
1178 __func__, (unsigned long long)sh->sector,
1eff9d32 1179 rbi->bi_opf, i);
977df362 1180 atomic_inc(&sh->count);
59fc630b 1181 if (sh != head_sh)
1182 atomic_inc(&head_sh->count);
05616be5 1183 if (use_new_offset(conf, sh))
4f024f37 1184 rbi->bi_iter.bi_sector = (sh->sector
05616be5
N		 1185 + rrdev->new_data_offset);
1186 else
4f024f37 1187 rbi->bi_iter.bi_sector = (sh->sector
05616be5 1188 + rrdev->data_offset);
d592a996
SL		 1189 if (test_bit(R5_SkipCopy, &sh->dev[i].flags))
1190 WARN_ON(test_bit(R5_UPTODATE, &sh->dev[i].flags));
1191 sh->dev[i].rvec.bv_page = sh->dev[i].page;
4997b72e 1192 rbi->bi_vcnt = 1;
977df362
N		 1193 rbi->bi_io_vec[0].bv_len = STRIPE_SIZE;
1194 rbi->bi_io_vec[0].bv_offset = 0;
4f024f37 1195 rbi->bi_iter.bi_size = STRIPE_SIZE;
2cd259a7
MD		 1196 rbi->bi_write_hint = sh->dev[i].write_hint;
1197 sh->dev[i].write_hint = RWF_WRITE_LIFE_NOT_SET;
37c61ff3
SL		 1198 /*
1199 * If this is discard request, set bi_vcnt 0. We don't
1200 * want to confuse SCSI because SCSI will replace payload
1201 */
796a5cf0 1202 if (op == REQ_OP_DISCARD)
37c61ff3 1203 rbi->bi_vcnt = 0;
e3620a3a 1204 if (conf->mddev->gendisk)
74d46992 1205 trace_block_bio_remap(rbi->bi_disk->queue,
e3620a3a
JB		 1206 rbi, disk_devt(conf->mddev->gendisk),
1207 sh->dev[i].sector);
aaf9f12e
SL		 1208 if (should_defer && op_is_write(op))
1209 bio_list_add(&pending_bios, rbi);
1210 else
1211 generic_make_request(rbi);
977df362
N		 1212 }
1213 if (!rdev && !rrdev) {
796a5cf0 1214 if (op_is_write(op))
91c00924 1215 set_bit(STRIPE_DEGRADED, &sh->state);
6296b960 1216 pr_debug("skip op %d on disc %d for sector %llu\n",
1eff9d32 1217 bi->bi_opf, i, (unsigned long long)sh->sector);
91c00924
DW		 1218 clear_bit(R5_LOCKED, &sh->dev[i].flags);
1219 set_bit(STRIPE_HANDLE, &sh->state);
1220 }
59fc630b 1221
1222 if (!head_sh->batch_head)
1223 continue;
1224 sh = list_first_entry(&sh->batch_list, struct stripe_head,
1225 batch_list);
1226 if (sh != head_sh)
1227 goto again;
91c00924 1228 }
aaf9f12e
SL		 1229
1230 if (should_defer && !bio_list_empty(&pending_bios))
1231 defer_issue_bios(conf, head_sh->sector, &pending_bios);
91c00924
DW		 1232}
1233
1234static struct dma_async_tx_descriptor *
d592a996
SL		 1235async_copy_data(int frombio, struct bio *bio, struct page **page,
1236 sector_t sector, struct dma_async_tx_descriptor *tx,
1e6d690b 1237 struct stripe_head *sh, int no_skipcopy)
91c00924 1238{
7988613b
KO		 1239 struct bio_vec bvl;
1240 struct bvec_iter iter;
91c00924 1241 struct page *bio_page;
91c00924 1242 int page_offset;
a08abd8c 1243 struct async_submit_ctl submit;
0403e382 1244 enum async_tx_flags flags = 0;
91c00924 1245
4f024f37
KO		 1246 if (bio->bi_iter.bi_sector >= sector)
1247 page_offset = (signed)(bio->bi_iter.bi_sector - sector) * 512;
91c00924 1248 else
4f024f37 1249 page_offset = (signed)(sector - bio->bi_iter.bi_sector) * -512;
a08abd8c 1250
0403e382
DW		 1251 if (frombio)
1252 flags |= ASYNC_TX_FENCE;
1253 init_async_submit(&submit, flags, tx, NULL, NULL, NULL);
1254
7988613b
KO		 1255 bio_for_each_segment(bvl, bio, iter) {
1256 int len = bvl.bv_len;
91c00924
DW		 1257 int clen;
1258 int b_offset = 0;
1259
1260 if (page_offset < 0) {
1261 b_offset = -page_offset;
1262 page_offset += b_offset;
1263 len -= b_offset;
1264 }
1265
1266 if (len > 0 && page_offset + len > STRIPE_SIZE)
1267 clen = STRIPE_SIZE - page_offset;
1268 else
1269 clen = len;
1270
1271 if (clen > 0) {
7988613b
KO		 1272 b_offset += bvl.bv_offset;
1273 bio_page = bvl.bv_page;
d592a996
SL		 1274 if (frombio) {
1275 if (sh->raid_conf->skip_copy &&
1276 b_offset == 0 && page_offset == 0 &&
1e6d690b
SL		 1277 clen == STRIPE_SIZE &&
1278 !no_skipcopy)
d592a996
SL		 1279 *page = bio_page;
1280 else
1281 tx = async_memcpy(*page, bio_page, page_offset,
a08abd8c 1282 b_offset, clen, &submit);
d592a996
SL		 1283 } else
1284 tx = async_memcpy(bio_page, *page, b_offset,
a08abd8c 1285 page_offset, clen, &submit);
91c00924 1286 }
a08abd8c
DW		 1287 /* chain the operations */
1288 submit.depend_tx = tx;
1289
91c00924
DW		 1290 if (clen < len) /* hit end of page */
1291 break;
1292 page_offset += len;
1293 }
1294
1295 return tx;
1296}
1297
1298static void ops_complete_biofill(void *stripe_head_ref)
1299{
1300 struct stripe_head *sh = stripe_head_ref;
e4d84909 1301 int i;
91c00924 1302
e46b272b 1303 pr_debug("%s: stripe %llu\n", __func__,
91c00924
DW		 1304 (unsigned long long)sh->sector);
1305
1306 /* clear completed biofills */
1307 for (i = sh->disks; i--; ) {
1308 struct r5dev *dev = &sh->dev[i];
91c00924
DW		 1309
1310 /* acknowledge completion of a biofill operation */
e4d84909
DW		 1311 /* and check if we need to reply to a read request,
1312 * new R5_Wantfill requests are held off until
83de75cc 1313 * !STRIPE_BIOFILL_RUN
e4d84909
DW		 1314 */
1315 if (test_and_clear_bit(R5_Wantfill, &dev->flags)) {
91c00924 1316 struct bio *rbi, *rbi2;
91c00924 1317
91c00924
DW		 1318 BUG_ON(!dev->read);
1319 rbi = dev->read;
1320 dev->read = NULL;
4f024f37 1321 while (rbi && rbi->bi_iter.bi_sector <
91c00924
DW		 1322 dev->sector + STRIPE_SECTORS) {
1323 rbi2 = r5_next_bio(rbi, dev->sector);
016c76ac 1324 bio_endio(rbi);
91c00924
DW		 1325 rbi = rbi2;
1326 }
1327 }
1328 }
83de75cc 1329 clear_bit(STRIPE_BIOFILL_RUN, &sh->state);
91c00924 1330
e4d84909 1331 set_bit(STRIPE_HANDLE, &sh->state);
6d036f7d 1332 raid5_release_stripe(sh);
91c00924
DW		 1333}
1334
1335static void ops_run_biofill(struct stripe_head *sh)
1336{
1337 struct dma_async_tx_descriptor *tx = NULL;
a08abd8c 1338 struct async_submit_ctl submit;
91c00924
DW		 1339 int i;
1340
59fc630b 1341 BUG_ON(sh->batch_head);
e46b272b 1342 pr_debug("%s: stripe %llu\n", __func__,
91c00924
DW		 1343 (unsigned long long)sh->sector);
1344
1345 for (i = sh->disks; i--; ) {
1346 struct r5dev *dev = &sh->dev[i];
1347 if (test_bit(R5_Wantfill, &dev->flags)) {
1348 struct bio *rbi;
b17459c0 1349 spin_lock_irq(&sh->stripe_lock);
91c00924
DW		 1350 dev->read = rbi = dev->toread;
1351 dev->toread = NULL;
b17459c0 1352 spin_unlock_irq(&sh->stripe_lock);
4f024f37 1353 while (rbi && rbi->bi_iter.bi_sector <
91c00924 1354 dev->sector + STRIPE_SECTORS) {
d592a996 1355 tx = async_copy_data(0, rbi, &dev->page,
1e6d690b 1356 dev->sector, tx, sh, 0);
91c00924
DW		 1357 rbi = r5_next_bio(rbi, dev->sector);
1358 }
1359 }
1360 }
1361
1362 atomic_inc(&sh->count);
a08abd8c
DW		 1363 init_async_submit(&submit, ASYNC_TX_ACK, tx, ops_complete_biofill, sh, NULL);
1364 async_trigger_callback(&submit);
91c00924
DW		 1365}
1366
4e7d2c0a 1367static void mark_target_uptodate(struct stripe_head *sh, int target)
91c00924 1368{
4e7d2c0a 1369 struct r5dev *tgt;
91c00924 1370
4e7d2c0a
DW		 1371 if (target < 0)
1372 return;
91c00924 1373
4e7d2c0a 1374 tgt = &sh->dev[target];
91c00924
DW		 1375 set_bit(R5_UPTODATE, &tgt->flags);
1376 BUG_ON(!test_bit(R5_Wantcompute, &tgt->flags));
1377 clear_bit(R5_Wantcompute, &tgt->flags);
4e7d2c0a
DW		 1378}
1379
ac6b53b6 1380static void ops_complete_compute(void *stripe_head_ref)
91c00924
DW		 1381{
1382 struct stripe_head *sh = stripe_head_ref;
91c00924 1383
e46b272b 1384 pr_debug("%s: stripe %llu\n", __func__,
91c00924
DW		 1385 (unsigned long long)sh->sector);
1386
ac6b53b6 1387 /* mark the computed target(s) as uptodate */
4e7d2c0a 1388 mark_target_uptodate(sh, sh->ops.target);
ac6b53b6 1389 mark_target_uptodate(sh, sh->ops.target2);
4e7d2c0a 1390
ecc65c9b
DW		 1391 clear_bit(STRIPE_COMPUTE_RUN, &sh->state);
1392 if (sh->check_state == check_state_compute_run)
1393 sh->check_state = check_state_compute_result;
91c00924 1394 set_bit(STRIPE_HANDLE, &sh->state);
6d036f7d 1395 raid5_release_stripe(sh);
91c00924
DW		 1396}
1397
d6f38f31
DW		 1398/* return a pointer to the address conversion region of the scribble buffer */
1399static addr_conv_t *to_addr_conv(struct stripe_head *sh,
46d5b785 1400 struct raid5_percpu *percpu, int i)
d6f38f31 1401{
46d5b785 1402 void *addr;
1403
1404 addr = flex_array_get(percpu->scribble, i);
1405 return addr + sizeof(struct page *) * (sh->disks + 2);
1406}
1407
1408/* return a pointer to the address conversion region of the scribble buffer */
1409static struct page **to_addr_page(struct raid5_percpu *percpu, int i)
1410{
1411 void *addr;
1412
1413 addr = flex_array_get(percpu->scribble, i);
1414 return addr;
d6f38f31
DW		 1415}
1416
1417static struct dma_async_tx_descriptor *
1418ops_run_compute5(struct stripe_head *sh, struct raid5_percpu *percpu)
91c00924 1419{
91c00924 1420 int disks = sh->disks;
46d5b785 1421 struct page **xor_srcs = to_addr_page(percpu, 0);
91c00924
DW		 1422 int target = sh->ops.target;
1423 struct r5dev *tgt = &sh->dev[target];
1424 struct page *xor_dest = tgt->page;
1425 int count = 0;
1426 struct dma_async_tx_descriptor *tx;
a08abd8c 1427 struct async_submit_ctl submit;
91c00924
DW		 1428 int i;
1429
59fc630b 1430 BUG_ON(sh->batch_head);
1431
91c00924 1432 pr_debug("%s: stripe %llu block: %d\n",
e46b272b 1433 __func__, (unsigned long long)sh->sector, target);
91c00924
DW		 1434 BUG_ON(!test_bit(R5_Wantcompute, &tgt->flags));
1435
1436 for (i = disks; i--; )
1437 if (i != target)
1438 xor_srcs[count++] = sh->dev[i].page;
1439
1440 atomic_inc(&sh->count);
1441
0403e382 1442 init_async_submit(&submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_ZERO_DST, NULL,
46d5b785 1443 ops_complete_compute, sh, to_addr_conv(sh, percpu, 0));
91c00924 1444 if (unlikely(count == 1))
a08abd8c 1445 tx = async_memcpy(xor_dest, xor_srcs[0], 0, 0, STRIPE_SIZE, &submit);
91c00924 1446 else
a08abd8c 1447 tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, &submit);
91c00924 1448
91c00924
DW		 1449 return tx;
1450}
1451
ac6b53b6
DW		 1452/* set_syndrome_sources - populate source buffers for gen_syndrome
1453 * @srcs - (struct page *) array of size sh->disks
1454 * @sh - stripe_head to parse
1455 *
1456 * Populates srcs in proper layout order for the stripe and returns the
1457 * 'count' of sources to be used in a call to async_gen_syndrome. The P
1458 * destination buffer is recorded in srcs[count] and the Q destination
1459 * is recorded in srcs[count+1]].
1460 */
584acdd4
MS		 1461static int set_syndrome_sources(struct page **srcs,
1462 struct stripe_head *sh,
1463 int srctype)
ac6b53b6
DW		 1464{
1465 int disks = sh->disks;
1466 int syndrome_disks = sh->ddf_layout ? disks : (disks - 2);
1467 int d0_idx = raid6_d0(sh);
1468 int count;
1469 int i;
1470
1471 for (i = 0; i < disks; i++)
5dd33c9a 1472 srcs[i] = NULL;
ac6b53b6
DW		 1473
1474 count = 0;
1475 i = d0_idx;
1476 do {
1477 int slot = raid6_idx_to_slot(i, sh, &count, syndrome_disks);
584acdd4 1478 struct r5dev *dev = &sh->dev[i];
ac6b53b6 1479
584acdd4
MS		 1480 if (i == sh->qd_idx || i == sh->pd_idx ||
1481 (srctype == SYNDROME_SRC_ALL) ||
1482 (srctype == SYNDROME_SRC_WANT_DRAIN &&
1e6d690b
SL		 1483 (test_bit(R5_Wantdrain, &dev->flags) ||
1484 test_bit(R5_InJournal, &dev->flags))) ||
584acdd4 1485 (srctype == SYNDROME_SRC_WRITTEN &&
0977762f
SL		 1486 (dev->written ||
1487 test_bit(R5_InJournal, &dev->flags)))) {
1e6d690b
SL		 1488 if (test_bit(R5_InJournal, &dev->flags))
1489 srcs[slot] = sh->dev[i].orig_page;
1490 else
1491 srcs[slot] = sh->dev[i].page;
1492 }
ac6b53b6
DW		 1493 i = raid6_next_disk(i, disks);
1494 } while (i != d0_idx);
ac6b53b6 1495
e4424fee 1496 return syndrome_disks;
ac6b53b6
DW		 1497}
1498
1499static struct dma_async_tx_descriptor *
1500ops_run_compute6_1(struct stripe_head *sh, struct raid5_percpu *percpu)
1501{
1502 int disks = sh->disks;
46d5b785 1503 struct page **blocks = to_addr_page(percpu, 0);
ac6b53b6
DW		 1504 int target;
1505 int qd_idx = sh->qd_idx;
1506 struct dma_async_tx_descriptor *tx;
1507 struct async_submit_ctl submit;
1508 struct r5dev *tgt;
1509 struct page *dest;
1510 int i;
1511 int count;
1512
59fc630b 1513 BUG_ON(sh->batch_head);
ac6b53b6
DW		 1514 if (sh->ops.target < 0)
1515 target = sh->ops.target2;
1516 else if (sh->ops.target2 < 0)
1517 target = sh->ops.target;
91c00924 1518 else
ac6b53b6
DW		 1519 /* we should only have one valid target */
1520 BUG();
1521 BUG_ON(target < 0);
1522 pr_debug("%s: stripe %llu block: %d\n",
1523 __func__, (unsigned long long)sh->sector, target);
1524
1525 tgt = &sh->dev[target];
1526 BUG_ON(!test_bit(R5_Wantcompute, &tgt->flags));
1527 dest = tgt->page;
1528
1529 atomic_inc(&sh->count);
1530
1531 if (target == qd_idx) {
584acdd4 1532 count = set_syndrome_sources(blocks, sh, SYNDROME_SRC_ALL);
ac6b53b6
DW		 1533 blocks[count] = NULL; /* regenerating p is not necessary */
1534 BUG_ON(blocks[count+1] != dest); /* q should already be set */
0403e382
DW		 1535 init_async_submit(&submit, ASYNC_TX_FENCE, NULL,
1536 ops_complete_compute, sh,
46d5b785 1537 to_addr_conv(sh, percpu, 0));
ac6b53b6
DW		 1538 tx = async_gen_syndrome(blocks, 0, count+2, STRIPE_SIZE, &submit);
1539 } else {
1540 /* Compute any data- or p-drive using XOR */
1541 count = 0;
1542 for (i = disks; i-- ; ) {
1543 if (i == target || i == qd_idx)
1544 continue;
1545 blocks[count++] = sh->dev[i].page;
1546 }
1547
0403e382
DW		 1548 init_async_submit(&submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_ZERO_DST,
1549 NULL, ops_complete_compute, sh,
46d5b785 1550 to_addr_conv(sh, percpu, 0));
ac6b53b6
DW		 1551 tx = async_xor(dest, blocks, 0, count, STRIPE_SIZE, &submit);
1552 }
91c00924 1553
91c00924
DW		 1554 return tx;
1555}
1556
ac6b53b6
DW		 1557static struct dma_async_tx_descriptor *
1558ops_run_compute6_2(struct stripe_head *sh, struct raid5_percpu *percpu)
1559{
1560 int i, count, disks = sh->disks;
1561 int syndrome_disks = sh->ddf_layout ? disks : disks-2;
1562 int d0_idx = raid6_d0(sh);
1563 int faila = -1, failb = -1;
1564 int target = sh->ops.target;
1565 int target2 = sh->ops.target2;
1566 struct r5dev *tgt = &sh->dev[target];
1567 struct r5dev *tgt2 = &sh->dev[target2];
1568 struct dma_async_tx_descriptor *tx;
46d5b785 1569 struct page **blocks = to_addr_page(percpu, 0);
ac6b53b6
DW		 1570 struct async_submit_ctl submit;
1571
59fc630b 1572 BUG_ON(sh->batch_head);
ac6b53b6
DW		 1573 pr_debug("%s: stripe %llu block1: %d block2: %d\n",
1574 __func__, (unsigned long long)sh->sector, target, target2);
1575 BUG_ON(target < 0 || target2 < 0);
1576 BUG_ON(!test_bit(R5_Wantcompute, &tgt->flags));
1577 BUG_ON(!test_bit(R5_Wantcompute, &tgt2->flags));
1578
6c910a78 1579 /* we need to open-code set_syndrome_sources to handle the
ac6b53b6
DW		 1580 * slot number conversion for 'faila' and 'failb'
1581 */
1582 for (i = 0; i < disks ; i++)
5dd33c9a 1583 blocks[i] = NULL;
ac6b53b6
DW		 1584 count = 0;
1585 i = d0_idx;
1586 do {
1587 int slot = raid6_idx_to_slot(i, sh, &count, syndrome_disks);
1588
1589 blocks[slot] = sh->dev[i].page;
1590
1591 if (i == target)
1592 faila = slot;
1593 if (i == target2)
1594 failb = slot;
1595 i = raid6_next_disk(i, disks);
1596 } while (i != d0_idx);
ac6b53b6
DW		 1597
1598 BUG_ON(faila == failb);
1599 if (failb < faila)
1600 swap(faila, failb);
1601 pr_debug("%s: stripe: %llu faila: %d failb: %d\n",
1602 __func__, (unsigned long long)sh->sector, faila, failb);
1603
1604 atomic_inc(&sh->count);
1605
1606 if (failb == syndrome_disks+1) {
1607 /* Q disk is one of the missing disks */
1608 if (faila == syndrome_disks) {
1609 /* Missing P+Q, just recompute */
0403e382
DW		 1610 init_async_submit(&submit, ASYNC_TX_FENCE, NULL,
1611 ops_complete_compute, sh,
46d5b785 1612 to_addr_conv(sh, percpu, 0));
e4424fee 1613 return async_gen_syndrome(blocks, 0, syndrome_disks+2,
ac6b53b6
DW		 1614 STRIPE_SIZE, &submit);
1615 } else {
1616 struct page *dest;
1617 int data_target;
1618 int qd_idx = sh->qd_idx;
1619
1620 /* Missing D+Q: recompute D from P, then recompute Q */
1621 if (target == qd_idx)
1622 data_target = target2;
1623 else
1624 data_target = target;
1625
1626 count = 0;
1627 for (i = disks; i-- ; ) {
1628 if (i == data_target || i == qd_idx)
1629 continue;
1630 blocks[count++] = sh->dev[i].page;
1631 }
1632 dest = sh->dev[data_target].page;
0403e382
DW		 1633 init_async_submit(&submit,
1634 ASYNC_TX_FENCE|ASYNC_TX_XOR_ZERO_DST,
1635 NULL, NULL, NULL,
46d5b785 1636 to_addr_conv(sh, percpu, 0));
ac6b53b6
DW		 1637 tx = async_xor(dest, blocks, 0, count, STRIPE_SIZE,
1638 &submit);
1639
584acdd4 1640 count = set_syndrome_sources(blocks, sh, SYNDROME_SRC_ALL);
0403e382
DW		 1641 init_async_submit(&submit, ASYNC_TX_FENCE, tx,
1642 ops_complete_compute, sh,
46d5b785 1643 to_addr_conv(sh, percpu, 0));
ac6b53b6
DW		 1644 return async_gen_syndrome(blocks, 0, count+2,
1645 STRIPE_SIZE, &submit);
1646 }
ac6b53b6 1647 } else {
6c910a78
DW		 1648 init_async_submit(&submit, ASYNC_TX_FENCE, NULL,
1649 ops_complete_compute, sh,
46d5b785 1650 to_addr_conv(sh, percpu, 0));
6c910a78
DW		 1651 if (failb == syndrome_disks) {
1652 /* We're missing D+P. */
1653 return async_raid6_datap_recov(syndrome_disks+2,
1654 STRIPE_SIZE, faila,
1655 blocks, &submit);
1656 } else {
1657 /* We're missing D+D. */
1658 return async_raid6_2data_recov(syndrome_disks+2,
1659 STRIPE_SIZE, faila, failb,
1660 blocks, &submit);
1661 }
ac6b53b6
DW		 1662 }
1663}
1664
91c00924
DW		 1665static void ops_complete_prexor(void *stripe_head_ref)
1666{
1667 struct stripe_head *sh = stripe_head_ref;
1668
e46b272b 1669 pr_debug("%s: stripe %llu\n", __func__,
91c00924 1670 (unsigned long long)sh->sector);
1e6d690b
SL		 1671
1672 if (r5c_is_writeback(sh->raid_conf->log))
1673 /*
1674 * raid5-cache write back uses orig_page during prexor.
1675 * After prexor, it is time to free orig_page
1676 */
1677 r5c_release_extra_page(sh);
91c00924
DW		 1678}
1679
1680static struct dma_async_tx_descriptor *
584acdd4
MS		 1681ops_run_prexor5(struct stripe_head *sh, struct raid5_percpu *percpu,
1682 struct dma_async_tx_descriptor *tx)
91c00924 1683{
91c00924 1684 int disks = sh->disks;
46d5b785 1685 struct page **xor_srcs = to_addr_page(percpu, 0);
91c00924 1686 int count = 0, pd_idx = sh->pd_idx, i;
a08abd8c 1687 struct async_submit_ctl submit;
91c00924
DW		 1688
1689 /* existing parity data subtracted */
1690 struct page *xor_dest = xor_srcs[count++] = sh->dev[pd_idx].page;
1691
59fc630b 1692 BUG_ON(sh->batch_head);
e46b272b 1693 pr_debug("%s: stripe %llu\n", __func__,
91c00924
DW		 1694 (unsigned long long)sh->sector);
1695
1696 for (i = disks; i--; ) {
1697 struct r5dev *dev = &sh->dev[i];
1698 /* Only process blocks that are known to be uptodate */
1e6d690b
SL		 1699 if (test_bit(R5_InJournal, &dev->flags))
1700 xor_srcs[count++] = dev->orig_page;
1701 else if (test_bit(R5_Wantdrain, &dev->flags))
91c00924
DW		 1702 xor_srcs[count++] = dev->page;
1703 }
1704
0403e382 1705 init_async_submit(&submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_DROP_DST, tx,
46d5b785 1706 ops_complete_prexor, sh, to_addr_conv(sh, percpu, 0));
a08abd8c 1707 tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, &submit);
91c00924
DW		 1708
1709 return tx;
1710}
1711
584acdd4
MS		 1712static struct dma_async_tx_descriptor *
1713ops_run_prexor6(struct stripe_head *sh, struct raid5_percpu *percpu,
1714 struct dma_async_tx_descriptor *tx)
1715{
1716 struct page **blocks = to_addr_page(percpu, 0);
1717 int count;
1718 struct async_submit_ctl submit;
1719
1720 pr_debug("%s: stripe %llu\n", __func__,
1721 (unsigned long long)sh->sector);
1722
1723 count = set_syndrome_sources(blocks, sh, SYNDROME_SRC_WANT_DRAIN);
1724
1725 init_async_submit(&submit, ASYNC_TX_FENCE|ASYNC_TX_PQ_XOR_DST, tx,
1726 ops_complete_prexor, sh, to_addr_conv(sh, percpu, 0));
1727 tx = async_gen_syndrome(blocks, 0, count+2, STRIPE_SIZE, &submit);
1728
1729 return tx;
1730}
1731
91c00924 1732static struct dma_async_tx_descriptor *
d8ee0728 1733ops_run_biodrain(struct stripe_head *sh, struct dma_async_tx_descriptor *tx)
91c00924 1734{
1e6d690b 1735 struct r5conf *conf = sh->raid_conf;
91c00924 1736 int disks = sh->disks;
d8ee0728 1737 int i;
59fc630b 1738 struct stripe_head *head_sh = sh;
91c00924 1739
e46b272b 1740 pr_debug("%s: stripe %llu\n", __func__,
91c00924
DW		 1741 (unsigned long long)sh->sector);
1742
1743 for (i = disks; i--; ) {
59fc630b 1744 struct r5dev *dev;
91c00924 1745 struct bio *chosen;
91c00924 1746
59fc630b 1747 sh = head_sh;
1748 if (test_and_clear_bit(R5_Wantdrain, &head_sh->dev[i].flags)) {
91c00924
DW		 1749 struct bio *wbi;
1750
59fc630b 1751again:
1752 dev = &sh->dev[i];
1e6d690b
SL		 1753 /*
1754 * clear R5_InJournal, so when rewriting a page in
1755 * journal, it is not skipped by r5l_log_stripe()
1756 */
1757 clear_bit(R5_InJournal, &dev->flags);
b17459c0 1758 spin_lock_irq(&sh->stripe_lock);
91c00924
DW		 1759 chosen = dev->towrite;
1760 dev->towrite = NULL;
7a87f434 1761 sh->overwrite_disks = 0;
91c00924
DW		 1762 BUG_ON(dev->written);
1763 wbi = dev->written = chosen;
b17459c0 1764 spin_unlock_irq(&sh->stripe_lock);
d592a996 1765 WARN_ON(dev->page != dev->orig_page);
91c00924 1766
4f024f37 1767 while (wbi && wbi->bi_iter.bi_sector <
91c00924 1768 dev->sector + STRIPE_SECTORS) {
1eff9d32 1769 if (wbi->bi_opf & REQ_FUA)
e9c7469b 1770 set_bit(R5_WantFUA, &dev->flags);
1eff9d32 1771 if (wbi->bi_opf & REQ_SYNC)
bc0934f0 1772 set_bit(R5_SyncIO, &dev->flags);
796a5cf0 1773 if (bio_op(wbi) == REQ_OP_DISCARD)
620125f2 1774 set_bit(R5_Discard, &dev->flags);
d592a996
SL		 1775 else {
1776 tx = async_copy_data(1, wbi, &dev->page,
1e6d690b
SL		 1777 dev->sector, tx, sh,
1778 r5c_is_writeback(conf->log));
1779 if (dev->page != dev->orig_page &&
1780 !r5c_is_writeback(conf->log)) {
d592a996
SL		 1781 set_bit(R5_SkipCopy, &dev->flags);
1782 clear_bit(R5_UPTODATE, &dev->flags);
1783 clear_bit(R5_OVERWRITE, &dev->flags);
1784 }
1785 }
91c00924
DW		 1786 wbi = r5_next_bio(wbi, dev->sector);
1787 }
59fc630b 1788
1789 if (head_sh->batch_head) {
1790 sh = list_first_entry(&sh->batch_list,
1791 struct stripe_head,
1792 batch_list);
1793 if (sh == head_sh)
1794 continue;
1795 goto again;
1796 }
91c00924
DW		 1797 }
1798 }
1799
1800 return tx;
1801}
1802
ac6b53b6 1803static void ops_complete_reconstruct(void *stripe_head_ref)
91c00924
DW		 1804{
1805 struct stripe_head *sh = stripe_head_ref;
ac6b53b6
DW		 1806 int disks = sh->disks;
1807 int pd_idx = sh->pd_idx;
1808 int qd_idx = sh->qd_idx;
1809 int i;
9e444768 1810 bool fua = false, sync = false, discard = false;
91c00924 1811
e46b272b 1812 pr_debug("%s: stripe %llu\n", __func__,
91c00924
DW		 1813 (unsigned long long)sh->sector);
1814
bc0934f0 1815 for (i = disks; i--; ) {
e9c7469b 1816 fua |= test_bit(R5_WantFUA, &sh->dev[i].flags);
bc0934f0 1817 sync |= test_bit(R5_SyncIO, &sh->dev[i].flags);
9e444768 1818 discard |= test_bit(R5_Discard, &sh->dev[i].flags);
bc0934f0 1819 }
e9c7469b 1820
91c00924
DW		 1821 for (i = disks; i--; ) {
1822 struct r5dev *dev = &sh->dev[i];
ac6b53b6 1823
e9c7469b 1824 if (dev->written || i == pd_idx || i == qd_idx) {
235b6003 1825 if (!discard && !test_bit(R5_SkipCopy, &dev->flags)) {
9e444768 1826 set_bit(R5_UPTODATE, &dev->flags);
235b6003
N		 1827 if (test_bit(STRIPE_EXPAND_READY, &sh->state))
1828 set_bit(R5_Expanded, &dev->flags);
1829 }
e9c7469b
TH		 1830 if (fua)
1831 set_bit(R5_WantFUA, &dev->flags);
bc0934f0
SL		 1832 if (sync)
1833 set_bit(R5_SyncIO, &dev->flags);
e9c7469b 1834 }
91c00924
DW		 1835 }
1836
d8ee0728
DW		 1837 if (sh->reconstruct_state == reconstruct_state_drain_run)
1838 sh->reconstruct_state = reconstruct_state_drain_result;
1839 else if (sh->reconstruct_state == reconstruct_state_prexor_drain_run)
1840 sh->reconstruct_state = reconstruct_state_prexor_drain_result;
1841 else {
1842 BUG_ON(sh->reconstruct_state != reconstruct_state_run);
1843 sh->reconstruct_state = reconstruct_state_result;
1844 }
91c00924
DW		 1845
1846 set_bit(STRIPE_HANDLE, &sh->state);
6d036f7d 1847 raid5_release_stripe(sh);
91c00924
DW		 1848}
1849
1850static void
ac6b53b6
DW		 1851ops_run_reconstruct5(struct stripe_head *sh, struct raid5_percpu *percpu,
1852 struct dma_async_tx_descriptor *tx)
91c00924 1853{
91c00924 1854 int disks = sh->disks;
59fc630b 1855 struct page **xor_srcs;
a08abd8c 1856 struct async_submit_ctl submit;
59fc630b 1857 int count, pd_idx = sh->pd_idx, i;
91c00924 1858 struct page *xor_dest;
d8ee0728 1859 int prexor = 0;
91c00924 1860 unsigned long flags;
59fc630b 1861 int j = 0;
1862 struct stripe_head *head_sh = sh;
1863 int last_stripe;
91c00924 1864
e46b272b 1865 pr_debug("%s: stripe %llu\n", __func__,
91c00924
DW		 1866 (unsigned long long)sh->sector);
1867
620125f2
SL		 1868 for (i = 0; i < sh->disks; i++) {
1869 if (pd_idx == i)
1870 continue;
1871 if (!test_bit(R5_Discard, &sh->dev[i].flags))
1872 break;
1873 }
1874 if (i >= sh->disks) {
1875 atomic_inc(&sh->count);
620125f2
SL		 1876 set_bit(R5_Discard, &sh->dev[pd_idx].flags);
1877 ops_complete_reconstruct(sh);
1878 return;
1879 }
59fc630b 1880again:
1881 count = 0;
1882 xor_srcs = to_addr_page(percpu, j);
91c00924
DW		 1883 /* check if prexor is active which means only process blocks
1884 * that are part of a read-modify-write (written)
1885 */
59fc630b 1886 if (head_sh->reconstruct_state == reconstruct_state_prexor_drain_run) {
d8ee0728 1887 prexor = 1;
91c00924
DW		 1888 xor_dest = xor_srcs[count++] = sh->dev[pd_idx].page;
1889 for (i = disks; i--; ) {
1890 struct r5dev *dev = &sh->dev[i];
1e6d690b
SL		 1891 if (head_sh->dev[i].written ||
1892 test_bit(R5_InJournal, &head_sh->dev[i].flags))
91c00924
DW		 1893 xor_srcs[count++] = dev->page;
1894 }
1895 } else {
1896 xor_dest = sh->dev[pd_idx].page;
1897 for (i = disks; i--; ) {
1898 struct r5dev *dev = &sh->dev[i];
1899 if (i != pd_idx)
1900 xor_srcs[count++] = dev->page;
1901 }
1902 }
1903
91c00924
DW		 1904 /* 1/ if we prexor'd then the dest is reused as a source
1905 * 2/ if we did not prexor then we are redoing the parity
1906 * set ASYNC_TX_XOR_DROP_DST and ASYNC_TX_XOR_ZERO_DST
1907 * for the synchronous xor case
1908 */
59fc630b 1909 last_stripe = !head_sh->batch_head ||
1910 list_first_entry(&sh->batch_list,
1911 struct stripe_head, batch_list) == head_sh;
1912 if (last_stripe) {
1913 flags = ASYNC_TX_ACK |
1914 (prexor ? ASYNC_TX_XOR_DROP_DST : ASYNC_TX_XOR_ZERO_DST);
1915
1916 atomic_inc(&head_sh->count);
1917 init_async_submit(&submit, flags, tx, ops_complete_reconstruct, head_sh,
1918 to_addr_conv(sh, percpu, j));
1919 } else {
1920 flags = prexor ? ASYNC_TX_XOR_DROP_DST : ASYNC_TX_XOR_ZERO_DST;
1921 init_async_submit(&submit, flags, tx, NULL, NULL,
1922 to_addr_conv(sh, percpu, j));
1923 }
91c00924 1924
a08abd8c
DW		 1925 if (unlikely(count == 1))
1926 tx = async_memcpy(xor_dest, xor_srcs[0], 0, 0, STRIPE_SIZE, &submit);
1927 else
1928 tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, &submit);
59fc630b 1929 if (!last_stripe) {
1930 j++;
1931 sh = list_first_entry(&sh->batch_list, struct stripe_head,
1932 batch_list);
1933 goto again;
1934 }
91c00924
DW		 1935}
1936
ac6b53b6
DW		 1937static void
1938ops_run_reconstruct6(struct stripe_head *sh, struct raid5_percpu *percpu,
1939 struct dma_async_tx_descriptor *tx)
1940{
1941 struct async_submit_ctl submit;
59fc630b 1942 struct page **blocks;
1943 int count, i, j = 0;
1944 struct stripe_head *head_sh = sh;
1945 int last_stripe;
584acdd4
MS		 1946 int synflags;
1947 unsigned long txflags;
ac6b53b6
DW		 1948
1949 pr_debug("%s: stripe %llu\n", __func__, (unsigned long long)sh->sector);
1950
620125f2
SL		 1951 for (i = 0; i < sh->disks; i++) {
1952 if (sh->pd_idx == i || sh->qd_idx == i)
1953 continue;
1954 if (!test_bit(R5_Discard, &sh->dev[i].flags))
1955 break;
1956 }
1957 if (i >= sh->disks) {
1958 atomic_inc(&sh->count);
620125f2
SL		 1959 set_bit(R5_Discard, &sh->dev[sh->pd_idx].flags);
1960 set_bit(R5_Discard, &sh->dev[sh->qd_idx].flags);
1961 ops_complete_reconstruct(sh);
1962 return;
1963 }
1964
59fc630b 1965again:
1966 blocks = to_addr_page(percpu, j);
584acdd4
MS		 1967
1968 if (sh->reconstruct_state == reconstruct_state_prexor_drain_run) {
1969 synflags = SYNDROME_SRC_WRITTEN;
1970 txflags = ASYNC_TX_ACK | ASYNC_TX_PQ_XOR_DST;
1971 } else {
1972 synflags = SYNDROME_SRC_ALL;
1973 txflags = ASYNC_TX_ACK;
1974 }
1975
1976 count = set_syndrome_sources(blocks, sh, synflags);
59fc630b 1977 last_stripe = !head_sh->batch_head ||
1978 list_first_entry(&sh->batch_list,
1979 struct stripe_head, batch_list) == head_sh;
1980
1981 if (last_stripe) {
1982 atomic_inc(&head_sh->count);
584acdd4 1983 init_async_submit(&submit, txflags, tx, ops_complete_reconstruct,
59fc630b 1984 head_sh, to_addr_conv(sh, percpu, j));
1985 } else
1986 init_async_submit(&submit, 0, tx, NULL, NULL,
1987 to_addr_conv(sh, percpu, j));
48769695 1988 tx = async_gen_syndrome(blocks, 0, count+2, STRIPE_SIZE, &submit);
59fc630b 1989 if (!last_stripe) {
1990 j++;
1991 sh = list_first_entry(&sh->batch_list, struct stripe_head,
1992 batch_list);
1993 goto again;
1994 }
91c00924
DW		 1995}
1996
1997static void ops_complete_check(void *stripe_head_ref)
1998{
1999 struct stripe_head *sh = stripe_head_ref;
91c00924 2000
e46b272b 2001 pr_debug("%s: stripe %llu\n", __func__,
91c00924
DW		 2002 (unsigned long long)sh->sector);
2003
ecc65c9b 2004 sh->check_state = check_state_check_result;
91c00924 2005 set_bit(STRIPE_HANDLE, &sh->state);
6d036f7d 2006 raid5_release_stripe(sh);
91c00924
DW		 2007}
2008
ac6b53b6 2009static void ops_run_check_p(struct stripe_head *sh, struct raid5_percpu *percpu)
91c00924 2010{
91c00924 2011 int disks = sh->disks;
ac6b53b6
DW		 2012 int pd_idx = sh->pd_idx;
2013 int qd_idx = sh->qd_idx;
2014 struct page *xor_dest;
46d5b785 2015 struct page **xor_srcs = to_addr_page(percpu, 0);
91c00924 2016 struct dma_async_tx_descriptor *tx;
a08abd8c 2017 struct async_submit_ctl submit;
ac6b53b6
DW		 2018 int count;
2019 int i;
91c00924 2020
e46b272b 2021 pr_debug("%s: stripe %llu\n", __func__,
91c00924
DW		 2022 (unsigned long long)sh->sector);
2023
59fc630b 2024 BUG_ON(sh->batch_head);
ac6b53b6
DW		 2025 count = 0;
2026 xor_dest = sh->dev[pd_idx].page;
2027 xor_srcs[count++] = xor_dest;
91c00924 2028 for (i = disks; i--; ) {
ac6b53b6
DW		 2029 if (i == pd_idx || i == qd_idx)
2030 continue;
2031 xor_srcs[count++] = sh->dev[i].page;
91c00924
DW		 2032 }
2033
d6f38f31 2034 init_async_submit(&submit, 0, NULL, NULL, NULL,
46d5b785 2035 to_addr_conv(sh, percpu, 0));
099f53cb 2036 tx = async_xor_val(xor_dest, xor_srcs, 0, count, STRIPE_SIZE,
a08abd8c 2037 &sh->ops.zero_sum_result, &submit);
91c00924 2038
91c00924 2039 atomic_inc(&sh->count);
a08abd8c
DW		 2040 init_async_submit(&submit, ASYNC_TX_ACK, tx, ops_complete_check, sh, NULL);
2041 tx = async_trigger_callback(&submit);
91c00924
DW		 2042}
2043
ac6b53b6
DW		 2044static void ops_run_check_pq(struct stripe_head *sh, struct raid5_percpu *percpu, int checkp)
2045{
46d5b785 2046 struct page **srcs = to_addr_page(percpu, 0);
ac6b53b6
DW		 2047 struct async_submit_ctl submit;
2048 int count;
2049
2050 pr_debug("%s: stripe %llu checkp: %d\n", __func__,
2051 (unsigned long long)sh->sector, checkp);
2052
59fc630b 2053 BUG_ON(sh->batch_head);
584acdd4 2054 count = set_syndrome_sources(srcs, sh, SYNDROME_SRC_ALL);
ac6b53b6
DW		 2055 if (!checkp)
2056 srcs[count] = NULL;
91c00924 2057
91c00924 2058 atomic_inc(&sh->count);
ac6b53b6 2059 init_async_submit(&submit, ASYNC_TX_ACK, NULL, ops_complete_check,
46d5b785 2060 sh, to_addr_conv(sh, percpu, 0));
ac6b53b6
DW		 2061 async_syndrome_val(srcs, 0, count+2, STRIPE_SIZE,
2062 &sh->ops.zero_sum_result, percpu->spare_page, &submit);
91c00924
DW		 2063}
2064
51acbcec 2065static void raid_run_ops(struct stripe_head *sh, unsigned long ops_request)
91c00924
DW		 2066{
2067 int overlap_clear = 0, i, disks = sh->disks;
2068 struct dma_async_tx_descriptor *tx = NULL;
d1688a6d 2069 struct r5conf *conf = sh->raid_conf;
ac6b53b6 2070 int level = conf->level;
d6f38f31
DW		 2071 struct raid5_percpu *percpu;
2072 unsigned long cpu;
91c00924 2073
d6f38f31
DW		 2074 cpu = get_cpu();
2075 percpu = per_cpu_ptr(conf->percpu, cpu);
83de75cc 2076 if (test_bit(STRIPE_OP_BIOFILL, &ops_request)) {
91c00924
DW		 2077 ops_run_biofill(sh);
2078 overlap_clear++;
2079 }
2080
7b3a871e 2081 if (test_bit(STRIPE_OP_COMPUTE_BLK, &ops_request)) {
ac6b53b6
DW		 2082 if (level < 6)
2083 tx = ops_run_compute5(sh, percpu);
2084 else {
2085 if (sh->ops.target2 < 0 || sh->ops.target < 0)
2086 tx = ops_run_compute6_1(sh, percpu);
2087 else
2088 tx = ops_run_compute6_2(sh, percpu);
2089 }
2090 /* terminate the chain if reconstruct is not set to be run */
2091 if (tx && !test_bit(STRIPE_OP_RECONSTRUCT, &ops_request))
7b3a871e
DW		 2092 async_tx_ack(tx);
2093 }
91c00924 2094
584acdd4
MS		 2095 if (test_bit(STRIPE_OP_PREXOR, &ops_request)) {
2096 if (level < 6)
2097 tx = ops_run_prexor5(sh, percpu, tx);
2098 else
2099 tx = ops_run_prexor6(sh, percpu, tx);
2100 }
91c00924 2101
ae1713e2
AP		 2102 if (test_bit(STRIPE_OP_PARTIAL_PARITY, &ops_request))
2103 tx = ops_run_partial_parity(sh, percpu, tx);
2104
600aa109 2105 if (test_bit(STRIPE_OP_BIODRAIN, &ops_request)) {
d8ee0728 2106 tx = ops_run_biodrain(sh, tx);
91c00924
DW		 2107 overlap_clear++;
2108 }
2109
ac6b53b6
DW		 2110 if (test_bit(STRIPE_OP_RECONSTRUCT, &ops_request)) {
2111 if (level < 6)
2112 ops_run_reconstruct5(sh, percpu, tx);
2113 else
2114 ops_run_reconstruct6(sh, percpu, tx);
2115 }
91c00924 2116
ac6b53b6
DW		 2117 if (test_bit(STRIPE_OP_CHECK, &ops_request)) {
2118 if (sh->check_state == check_state_run)
2119 ops_run_check_p(sh, percpu);
2120 else if (sh->check_state == check_state_run_q)
2121 ops_run_check_pq(sh, percpu, 0);
2122 else if (sh->check_state == check_state_run_pq)
2123 ops_run_check_pq(sh, percpu, 1);
2124 else
2125 BUG();
2126 }
91c00924 2127
59fc630b 2128 if (overlap_clear && !sh->batch_head)
91c00924
DW		 2129 for (i = disks; i--; ) {
2130 struct r5dev *dev = &sh->dev[i];
2131 if (test_and_clear_bit(R5_Overlap, &dev->flags))
2132 wake_up(&sh->raid_conf->wait_for_overlap);
2133 }
d6f38f31 2134 put_cpu();
91c00924
DW		 2135}
2136
845b9e22
AP		 2137static void free_stripe(struct kmem_cache *sc, struct stripe_head *sh)
2138{
2139 if (sh->ppl_page)
2140 __free_page(sh->ppl_page);
2141 kmem_cache_free(sc, sh);
2142}
2143
5f9d1fde 2144static struct stripe_head *alloc_stripe(struct kmem_cache *sc, gfp_t gfp,
845b9e22 2145 int disks, struct r5conf *conf)
f18c1a35
N		 2146{
2147 struct stripe_head *sh;
5f9d1fde 2148 int i;
f18c1a35
N		 2149
2150 sh = kmem_cache_zalloc(sc, gfp);
2151 if (sh) {
2152 spin_lock_init(&sh->stripe_lock);
2153 spin_lock_init(&sh->batch_lock);
2154 INIT_LIST_HEAD(&sh->batch_list);
2155 INIT_LIST_HEAD(&sh->lru);
a39f7afd 2156 INIT_LIST_HEAD(&sh->r5c);
d7bd398e 2157 INIT_LIST_HEAD(&sh->log_list);
f18c1a35 2158 atomic_set(&sh->count, 1);
845b9e22 2159 sh->raid_conf = conf;
a39f7afd 2160 sh->log_start = MaxSector;
5f9d1fde
SL		 2161 for (i = 0; i < disks; i++) {
2162 struct r5dev *dev = &sh->dev[i];
2163
3a83f467
ML		 2164 bio_init(&dev->req, &dev->vec, 1);
2165 bio_init(&dev->rreq, &dev->rvec, 1);
5f9d1fde 2166 }
845b9e22
AP		 2167
2168 if (raid5_has_ppl(conf)) {
2169 sh->ppl_page = alloc_page(gfp);
2170 if (!sh->ppl_page) {
2171 free_stripe(sc, sh);
2172 sh = NULL;
2173 }
2174 }
f18c1a35
N		 2175 }
2176 return sh;
2177}
486f0644 2178static int grow_one_stripe(struct r5conf *conf, gfp_t gfp)
1da177e4
LT		 2179{
2180 struct stripe_head *sh;
f18c1a35 2181
845b9e22 2182 sh = alloc_stripe(conf->slab_cache, gfp, conf->pool_size, conf);
3f294f4f
N		 2183 if (!sh)
2184 return 0;
6ce32846 2185
a9683a79 2186 if (grow_buffers(sh, gfp)) {
e4e11e38 2187 shrink_buffers(sh);
845b9e22 2188 free_stripe(conf->slab_cache, sh);
3f294f4f
N		 2189 return 0;
2190 }
486f0644
N		 2191 sh->hash_lock_index =
2192 conf->max_nr_stripes % NR_STRIPE_HASH_LOCKS;
3f294f4f 2193 /* we just created an active stripe so... */
3f294f4f 2194 atomic_inc(&conf->active_stripes);
59fc630b 2195
6d036f7d 2196 raid5_release_stripe(sh);
486f0644 2197 conf->max_nr_stripes++;
3f294f4f
N		 2198 return 1;
2199}
2200
d1688a6d 2201static int grow_stripes(struct r5conf *conf, int num)
3f294f4f 2202{
e18b890b 2203 struct kmem_cache *sc;
53b8d89d 2204 size_t namelen = sizeof(conf->cache_name[0]);
5e5e3e78 2205 int devs = max(conf->raid_disks, conf->previous_raid_disks);
1da177e4 2206
f4be6b43 2207 if (conf->mddev->gendisk)
53b8d89d 2208 snprintf(conf->cache_name[0], namelen,
f4be6b43
N		 2209 "raid%d-%s", conf->level, mdname(conf->mddev));
2210 else
53b8d89d 2211 snprintf(conf->cache_name[0], namelen,
f4be6b43 2212 "raid%d-%p", conf->level, conf->mddev);
53b8d89d 2213 snprintf(conf->cache_name[1], namelen, "%.27s-alt", conf->cache_name[0]);
f4be6b43 2214
ad01c9e3
N		 2215 conf->active_name = 0;
2216 sc = kmem_cache_create(conf->cache_name[conf->active_name],
1da177e4 2217 sizeof(struct stripe_head)+(devs-1)*sizeof(struct r5dev),
20c2df83 2218 0, 0, NULL);
1da177e4
LT		 2219 if (!sc)
2220 return 1;
2221 conf->slab_cache = sc;
ad01c9e3 2222 conf->pool_size = devs;
486f0644
N		 2223 while (num--)
2224 if (!grow_one_stripe(conf, GFP_KERNEL))
1da177e4 2225 return 1;
486f0644 2226
1da177e4
LT		 2227 return 0;
2228}
29269553 2229
d6f38f31
DW		 2230/**
2231 * scribble_len - return the required size of the scribble region
2232 * @num - total number of disks in the array
2233 *
2234 * The size must be enough to contain:
2235 * 1/ a struct page pointer for each device in the array +2
2236 * 2/ room to convert each entry in (1) to its corresponding dma
2237 * (dma_map_page()) or page (page_address()) address.
2238 *
2239 * Note: the +2 is for the destination buffers of the ddf/raid6 case where we
2240 * calculate over all devices (not just the data blocks), using zeros in place
2241 * of the P and Q blocks.
2242 */
46d5b785 2243static struct flex_array *scribble_alloc(int num, int cnt, gfp_t flags)
d6f38f31 2244{
46d5b785 2245 struct flex_array *ret;
d6f38f31
DW		 2246 size_t len;
2247
2248 len = sizeof(struct page *) * (num+2) + sizeof(addr_conv_t) * (num+2);
46d5b785 2249 ret = flex_array_alloc(len, cnt, flags);
2250 if (!ret)
2251 return NULL;
2252 /* always prealloc all elements, so no locking is required */
2253 if (flex_array_prealloc(ret, 0, cnt, flags)) {
2254 flex_array_free(ret);
2255 return NULL;
2256 }
2257 return ret;
d6f38f31
DW		 2258}
2259
738a2738
N		 2260static int resize_chunks(struct r5conf *conf, int new_disks, int new_sectors)
2261{
2262 unsigned long cpu;
2263 int err = 0;
2264
27a353c0
SL		 2265 /*
2266 * Never shrink. And mddev_suspend() could deadlock if this is called
2267 * from raid5d. In that case, scribble_disks and scribble_sectors
2268 * should equal to new_disks and new_sectors
2269 */
2270 if (conf->scribble_disks >= new_disks &&
2271 conf->scribble_sectors >= new_sectors)
2272 return 0;
738a2738
N		 2273 mddev_suspend(conf->mddev);
2274 get_online_cpus();
2275 for_each_present_cpu(cpu) {
2276 struct raid5_percpu *percpu;
2277 struct flex_array *scribble;
2278
2279 percpu = per_cpu_ptr(conf->percpu, cpu);
2280 scribble = scribble_alloc(new_disks,
2281 new_sectors / STRIPE_SECTORS,
2282 GFP_NOIO);
2283
2284 if (scribble) {
2285 flex_array_free(percpu->scribble);
2286 percpu->scribble = scribble;
2287 } else {
2288 err = -ENOMEM;
2289 break;
2290 }
2291 }
2292 put_online_cpus();
2293 mddev_resume(conf->mddev);
27a353c0
SL		 2294 if (!err) {
2295 conf->scribble_disks = new_disks;
2296 conf->scribble_sectors = new_sectors;
2297 }
738a2738
N		 2298 return err;
2299}
2300
d1688a6d 2301static int resize_stripes(struct r5conf *conf, int newsize)
ad01c9e3
N		 2302{
2303 /* Make all the stripes able to hold 'newsize' devices.
2304 * New slots in each stripe get 'page' set to a new page.
2305 *
2306 * This happens in stages:
2307 * 1/ create a new kmem_cache and allocate the required number of
2308 * stripe_heads.
83f0d77a 2309 * 2/ gather all the old stripe_heads and transfer the pages across
ad01c9e3
N		 2310 * to the new stripe_heads. This will have the side effect of
2311 * freezing the array as once all stripe_heads have been collected,
2312 * no IO will be possible. Old stripe heads are freed once their
2313 * pages have been transferred over, and the old kmem_cache is
2314 * freed when all stripes are done.
2315 * 3/ reallocate conf->disks to be suitable bigger. If this fails,
3560741e 2316 * we simple return a failure status - no need to clean anything up.
ad01c9e3
N		 2317 * 4/ allocate new pages for the new slots in the new stripe_heads.
2318 * If this fails, we don't bother trying the shrink the
2319 * stripe_heads down again, we just leave them as they are.
2320 * As each stripe_head is processed the new one is released into
2321 * active service.
2322 *
2323 * Once step2 is started, we cannot afford to wait for a write,
2324 * so we use GFP_NOIO allocations.
2325 */
2326 struct stripe_head *osh, *nsh;
2327 LIST_HEAD(newstripes);
2328 struct disk_info *ndisks;
2214c260 2329 int err = 0;
e18b890b 2330 struct kmem_cache *sc;
ad01c9e3 2331 int i;
566c09c5 2332 int hash, cnt;
ad01c9e3 2333
2214c260 2334 md_allow_write(conf->mddev);
2a2275d6 2335
ad01c9e3
N		 2336 /* Step 1 */
2337 sc = kmem_cache_create(conf->cache_name[1-conf->active_name],
2338 sizeof(struct stripe_head)+(newsize-1)*sizeof(struct r5dev),
20c2df83 2339 0, 0, NULL);
ad01c9e3
N		 2340 if (!sc)
2341 return -ENOMEM;
2342
2d5b569b
N		 2343 /* Need to ensure auto-resizing doesn't interfere */
2344 mutex_lock(&conf->cache_size_mutex);
2345
ad01c9e3 2346 for (i = conf->max_nr_stripes; i; i--) {
845b9e22 2347 nsh = alloc_stripe(sc, GFP_KERNEL, newsize, conf);
ad01c9e3
N		 2348 if (!nsh)
2349 break;
2350
ad01c9e3
N		 2351 list_add(&nsh->lru, &newstripes);
2352 }
2353 if (i) {
2354 /* didn't get enough, give up */
2355 while (!list_empty(&newstripes)) {
2356 nsh = list_entry(newstripes.next, struct stripe_head, lru);
2357 list_del(&nsh->lru);
845b9e22 2358 free_stripe(sc, nsh);
ad01c9e3
N		 2359 }
2360 kmem_cache_destroy(sc);
2d5b569b 2361 mutex_unlock(&conf->cache_size_mutex);
ad01c9e3
N		 2362 return -ENOMEM;
2363 }
2364 /* Step 2 - Must use GFP_NOIO now.
2365 * OK, we have enough stripes, start collecting inactive
2366 * stripes and copying them over
2367 */
566c09c5
SL		 2368 hash = 0;
2369 cnt = 0;
ad01c9e3 2370 list_for_each_entry(nsh, &newstripes, lru) {
566c09c5 2371 lock_device_hash_lock(conf, hash);
6ab2a4b8 2372 wait_event_cmd(conf->wait_for_stripe,
566c09c5
SL		 2373 !list_empty(conf->inactive_list + hash),
2374 unlock_device_hash_lock(conf, hash),
2375 lock_device_hash_lock(conf, hash));
2376 osh = get_free_stripe(conf, hash);
2377 unlock_device_hash_lock(conf, hash);
f18c1a35 2378
d592a996 2379 for(i=0; i<conf->pool_size; i++) {
ad01c9e3 2380 nsh->dev[i].page = osh->dev[i].page;
d592a996
SL		 2381 nsh->dev[i].orig_page = osh->dev[i].page;
2382 }
566c09c5 2383 nsh->hash_lock_index = hash;
845b9e22 2384 free_stripe(conf->slab_cache, osh);
566c09c5
SL		 2385 cnt++;
2386 if (cnt >= conf->max_nr_stripes / NR_STRIPE_HASH_LOCKS +
2387 !!((conf->max_nr_stripes % NR_STRIPE_HASH_LOCKS) > hash)) {
2388 hash++;
2389 cnt = 0;
2390 }
ad01c9e3
N		 2391 }
2392 kmem_cache_destroy(conf->slab_cache);
2393
2394 /* Step 3.
2395 * At this point, we are holding all the stripes so the array
2396 * is completely stalled, so now is a good time to resize
d6f38f31 2397 * conf->disks and the scribble region
ad01c9e3 2398 */
6396bb22 2399 ndisks = kcalloc(newsize, sizeof(struct disk_info), GFP_NOIO);
ad01c9e3 2400 if (ndisks) {
d7bd398e 2401 for (i = 0; i < conf->pool_size; i++)
ad01c9e3 2402 ndisks[i] = conf->disks[i];
d7bd398e
SL		 2403
2404 for (i = conf->pool_size; i < newsize; i++) {
2405 ndisks[i].extra_page = alloc_page(GFP_NOIO);
2406 if (!ndisks[i].extra_page)
2407 err = -ENOMEM;
2408 }
2409
2410 if (err) {
2411 for (i = conf->pool_size; i < newsize; i++)
2412 if (ndisks[i].extra_page)
2413 put_page(ndisks[i].extra_page);
2414 kfree(ndisks);
2415 } else {
2416 kfree(conf->disks);
2417 conf->disks = ndisks;
2418 }
ad01c9e3
N		 2419 } else
2420 err = -ENOMEM;
2421
2d5b569b 2422 mutex_unlock(&conf->cache_size_mutex);
583da48e
DY		 2423
2424 conf->slab_cache = sc;
2425 conf->active_name = 1-conf->active_name;
2426
ad01c9e3
N		 2427 /* Step 4, return new stripes to service */
2428 while(!list_empty(&newstripes)) {
2429 nsh = list_entry(newstripes.next, struct stripe_head, lru);
2430 list_del_init(&nsh->lru);
d6f38f31 2431
ad01c9e3
N		 2432 for (i=conf->raid_disks; i < newsize; i++)
2433 if (nsh->dev[i].page == NULL) {
2434 struct page *p = alloc_page(GFP_NOIO);
2435 nsh->dev[i].page = p;
d592a996 2436 nsh->dev[i].orig_page = p;
ad01c9e3
N		 2437 if (!p)
2438 err = -ENOMEM;
2439 }
6d036f7d 2440 raid5_release_stripe(nsh);
ad01c9e3
N		 2441 }
2442 /* critical section pass, GFP_NOIO no longer needed */
2443
6e9eac2d
N		 2444 if (!err)
2445 conf->pool_size = newsize;
ad01c9e3
N		 2446 return err;
2447}
1da177e4 2448
486f0644 2449static int drop_one_stripe(struct r5conf *conf)
1da177e4
LT		 2450{
2451 struct stripe_head *sh;
49895bcc 2452 int hash = (conf->max_nr_stripes - 1) & STRIPE_HASH_LOCKS_MASK;
1da177e4 2453
566c09c5
SL		 2454 spin_lock_irq(conf->hash_locks + hash);
2455 sh = get_free_stripe(conf, hash);
2456 spin_unlock_irq(conf->hash_locks + hash);
3f294f4f
N		 2457 if (!sh)
2458 return 0;
78bafebd 2459 BUG_ON(atomic_read(&sh->count));
e4e11e38 2460 shrink_buffers(sh);
845b9e22 2461 free_stripe(conf->slab_cache, sh);
3f294f4f 2462 atomic_dec(&conf->active_stripes);
486f0644 2463 conf->max_nr_stripes--;
3f294f4f
N		 2464 return 1;
2465}
2466
d1688a6d 2467static void shrink_stripes(struct r5conf *conf)
3f294f4f 2468{
486f0644
N		 2469 while (conf->max_nr_stripes &&
2470 drop_one_stripe(conf))
2471 ;
3f294f4f 2472
644df1a8 2473 kmem_cache_destroy(conf->slab_cache);
1da177e4
LT		 2474 conf->slab_cache = NULL;
2475}
2476
4246a0b6 2477static void raid5_end_read_request(struct bio * bi)
1da177e4 2478{
99c0fb5f 2479 struct stripe_head *sh = bi->bi_private;
d1688a6d 2480 struct r5conf *conf = sh->raid_conf;
7ecaa1e6 2481 int disks = sh->disks, i;
d6950432 2482 char b[BDEVNAME_SIZE];
dd054fce 2483 struct md_rdev *rdev = NULL;
05616be5 2484 sector_t s;
1da177e4
LT		 2485
2486 for (i=0 ; i<disks; i++)
2487 if (bi == &sh->dev[i].req)
2488 break;
2489
4246a0b6 2490 pr_debug("end_read_request %llu/%d, count: %d, error %d.\n",
45b4233c 2491 (unsigned long long)sh->sector, i, atomic_read(&sh->count),
4e4cbee9 2492 bi->bi_status);
1da177e4 2493 if (i == disks) {
5f9d1fde 2494 bio_reset(bi);
1da177e4 2495 BUG();
6712ecf8 2496 return;
1da177e4 2497 }
14a75d3e 2498 if (test_bit(R5_ReadRepl, &sh->dev[i].flags))
dd054fce
N		 2499 /* If replacement finished while this request was outstanding,
2500 * 'replacement' might be NULL already.
2501 * In that case it moved down to 'rdev'.
2502 * rdev is not removed until all requests are finished.
2503 */
14a75d3e 2504 rdev = conf->disks[i].replacement;
dd054fce 2505 if (!rdev)
14a75d3e 2506 rdev = conf->disks[i].rdev;
1da177e4 2507
05616be5
N		 2508 if (use_new_offset(conf, sh))
2509 s = sh->sector + rdev->new_data_offset;
2510 else
2511 s = sh->sector + rdev->data_offset;
4e4cbee9 2512 if (!bi->bi_status) {
1da177e4 2513 set_bit(R5_UPTODATE, &sh->dev[i].flags);
4e5314b5 2514 if (test_bit(R5_ReadError, &sh->dev[i].flags)) {
14a75d3e
N		 2515 /* Note that this cannot happen on a
2516 * replacement device. We just fail those on
2517 * any error
2518 */
cc6167b4
N		 2519 pr_info_ratelimited(
2520 "md/raid:%s: read error corrected (%lu sectors at %llu on %s)\n",
8bda470e 2521 mdname(conf->mddev), STRIPE_SECTORS,
05616be5 2522 (unsigned long long)s,
8bda470e 2523 bdevname(rdev->bdev, b));
ddd5115f 2524 atomic_add(STRIPE_SECTORS, &rdev->corrected_errors);
4e5314b5
N		 2525 clear_bit(R5_ReadError, &sh->dev[i].flags);
2526 clear_bit(R5_ReWrite, &sh->dev[i].flags);
3f9e7c14 2527 } else if (test_bit(R5_ReadNoMerge, &sh->dev[i].flags))
2528 clear_bit(R5_ReadNoMerge, &sh->dev[i].flags);
2529
86aa1397
SL		 2530 if (test_bit(R5_InJournal, &sh->dev[i].flags))
2531 /*
2532 * end read for a page in journal, this
2533 * must be preparing for prexor in rmw
2534 */
2535 set_bit(R5_OrigPageUPTDODATE, &sh->dev[i].flags);
2536
14a75d3e
N		 2537 if (atomic_read(&rdev->read_errors))
2538 atomic_set(&rdev->read_errors, 0);
1da177e4 2539 } else {
14a75d3e 2540 const char *bdn = bdevname(rdev->bdev, b);
ba22dcbf 2541 int retry = 0;
2e8ac303 2542 int set_bad = 0;
d6950432 2543
1da177e4 2544 clear_bit(R5_UPTODATE, &sh->dev[i].flags);
d6950432 2545 atomic_inc(&rdev->read_errors);
14a75d3e 2546 if (test_bit(R5_ReadRepl, &sh->dev[i].flags))
cc6167b4
N		 2547 pr_warn_ratelimited(
2548 "md/raid:%s: read error on replacement device (sector %llu on %s).\n",
14a75d3e 2549 mdname(conf->mddev),
05616be5 2550 (unsigned long long)s,
14a75d3e 2551 bdn);
2e8ac303 2552 else if (conf->mddev->degraded >= conf->max_degraded) {
2553 set_bad = 1;
cc6167b4
N		 2554 pr_warn_ratelimited(
2555 "md/raid:%s: read error not correctable (sector %llu on %s).\n",
8bda470e 2556 mdname(conf->mddev),
05616be5 2557 (unsigned long long)s,
8bda470e 2558 bdn);
2e8ac303 2559 } else if (test_bit(R5_ReWrite, &sh->dev[i].flags)) {
4e5314b5 2560 /* Oh, no!!! */
2e8ac303 2561 set_bad = 1;
cc6167b4
N		 2562 pr_warn_ratelimited(
2563 "md/raid:%s: read error NOT corrected!! (sector %llu on %s).\n",
8bda470e 2564 mdname(conf->mddev),
05616be5 2565 (unsigned long long)s,
8bda470e 2566 bdn);
2e8ac303 2567 } else if (atomic_read(&rdev->read_errors)
ba22dcbf 2568 > conf->max_nr_stripes)
cc6167b4 2569 pr_warn("md/raid:%s: Too many read errors, failing device %s.\n",
d6950432 2570 mdname(conf->mddev), bdn);
ba22dcbf
N		 2571 else
2572 retry = 1;
edfa1f65
BY		 2573 if (set_bad && test_bit(In_sync, &rdev->flags)
2574 && !test_bit(R5_ReadNoMerge, &sh->dev[i].flags))
2575 retry = 1;
ba22dcbf 2576 if (retry)
3f9e7c14 2577 if (test_bit(R5_ReadNoMerge, &sh->dev[i].flags)) {
2578 set_bit(R5_ReadError, &sh->dev[i].flags);
2579 clear_bit(R5_ReadNoMerge, &sh->dev[i].flags);
2580 } else
2581 set_bit(R5_ReadNoMerge, &sh->dev[i].flags);
ba22dcbf 2582 else {
4e5314b5
N		 2583 clear_bit(R5_ReadError, &sh->dev[i].flags);
2584 clear_bit(R5_ReWrite, &sh->dev[i].flags);
2e8ac303 2585 if (!(set_bad
2586 && test_bit(In_sync, &rdev->flags)
2587 && rdev_set_badblocks(
2588 rdev, sh->sector, STRIPE_SECTORS, 0)))
2589 md_error(conf->mddev, rdev);
ba22dcbf 2590 }
1da177e4 2591 }
14a75d3e 2592 rdev_dec_pending(rdev, conf->mddev);
c9445555 2593 bio_reset(bi);
1da177e4
LT		 2594 clear_bit(R5_LOCKED, &sh->dev[i].flags);
2595 set_bit(STRIPE_HANDLE, &sh->state);
6d036f7d 2596 raid5_release_stripe(sh);
1da177e4
LT		 2597}
2598
4246a0b6 2599static void raid5_end_write_request(struct bio *bi)
1da177e4 2600{
99c0fb5f 2601 struct stripe_head *sh = bi->bi_private;
d1688a6d 2602 struct r5conf *conf = sh->raid_conf;
7ecaa1e6 2603 int disks = sh->disks, i;
977df362 2604 struct md_rdev *uninitialized_var(rdev);
b84db560
N		 2605 sector_t first_bad;
2606 int bad_sectors;
977df362 2607 int replacement = 0;
1da177e4 2608
977df362
N		 2609 for (i = 0 ; i < disks; i++) {
2610 if (bi == &sh->dev[i].req) {
2611 rdev = conf->disks[i].rdev;
1da177e4 2612 break;
977df362
N		 2613 }
2614 if (bi == &sh->dev[i].rreq) {
2615 rdev = conf->disks[i].replacement;
dd054fce
N		 2616 if (rdev)
2617 replacement = 1;
2618 else
2619 /* rdev was removed and 'replacement'
2620 * replaced it. rdev is not removed
2621 * until all requests are finished.
2622 */
2623 rdev = conf->disks[i].rdev;
977df362
N		 2624 break;
2625 }
2626 }
4246a0b6 2627 pr_debug("end_write_request %llu/%d, count %d, error: %d.\n",
1da177e4 2628 (unsigned long long)sh->sector, i, atomic_read(&sh->count),
4e4cbee9 2629 bi->bi_status);
1da177e4 2630 if (i == disks) {
5f9d1fde 2631 bio_reset(bi);
1da177e4 2632 BUG();
6712ecf8 2633 return;
1da177e4
LT		 2634 }
2635
977df362 2636 if (replacement) {
4e4cbee9 2637 if (bi->bi_status)
977df362
N		 2638 md_error(conf->mddev, rdev);
2639 else if (is_badblock(rdev, sh->sector,
2640 STRIPE_SECTORS,
2641 &first_bad, &bad_sectors))
2642 set_bit(R5_MadeGoodRepl, &sh->dev[i].flags);
2643 } else {
4e4cbee9 2644 if (bi->bi_status) {
9f97e4b1 2645 set_bit(STRIPE_DEGRADED, &sh->state);
977df362
N		 2646 set_bit(WriteErrorSeen, &rdev->flags);
2647 set_bit(R5_WriteError, &sh->dev[i].flags);
3a6de292
N		 2648 if (!test_and_set_bit(WantReplacement, &rdev->flags))
2649 set_bit(MD_RECOVERY_NEEDED,
2650 &rdev->mddev->recovery);
977df362
N		 2651 } else if (is_badblock(rdev, sh->sector,
2652 STRIPE_SECTORS,
c0b32972 2653 &first_bad, &bad_sectors)) {
977df362 2654 set_bit(R5_MadeGood, &sh->dev[i].flags);
c0b32972
N		 2655 if (test_bit(R5_ReadError, &sh->dev[i].flags))
2656 /* That was a successful write so make
2657 * sure it looks like we already did
2658 * a re-write.
2659 */
2660 set_bit(R5_ReWrite, &sh->dev[i].flags);
2661 }
977df362
N		 2662 }
2663 rdev_dec_pending(rdev, conf->mddev);
1da177e4 2664
4e4cbee9 2665 if (sh->batch_head && bi->bi_status && !replacement)
72ac7330 2666 set_bit(STRIPE_BATCH_ERR, &sh->batch_head->state);
2667
c9445555 2668 bio_reset(bi);
977df362
N		 2669 if (!test_and_clear_bit(R5_DOUBLE_LOCKED, &sh->dev[i].flags))
2670 clear_bit(R5_LOCKED, &sh->dev[i].flags);
1da177e4 2671 set_bit(STRIPE_HANDLE, &sh->state);
6d036f7d 2672 raid5_release_stripe(sh);
59fc630b 2673
2674 if (sh->batch_head && sh != sh->batch_head)
6d036f7d 2675 raid5_release_stripe(sh->batch_head);
1da177e4
LT		 2676}
2677
849674e4 2678static void raid5_error(struct mddev *mddev, struct md_rdev *rdev)
1da177e4
LT		 2679{
2680 char b[BDEVNAME_SIZE];
d1688a6d 2681 struct r5conf *conf = mddev->private;
908f4fbd 2682 unsigned long flags;
0c55e022 2683 pr_debug("raid456: error called\n");
1da177e4 2684
908f4fbd 2685 spin_lock_irqsave(&conf->device_lock, flags);
aff69d89 2686 set_bit(Faulty, &rdev->flags);
908f4fbd 2687 clear_bit(In_sync, &rdev->flags);
2e38a37f 2688 mddev->degraded = raid5_calc_degraded(conf);
908f4fbd
N		 2689 spin_unlock_irqrestore(&conf->device_lock, flags);
2690 set_bit(MD_RECOVERY_INTR, &mddev->recovery);
2691
de393cde 2692 set_bit(Blocked, &rdev->flags);
2953079c
SL		 2693 set_mask_bits(&mddev->sb_flags, 0,
2694 BIT(MD_SB_CHANGE_DEVS) | BIT(MD_SB_CHANGE_PENDING));
cc6167b4
N		 2695 pr_crit("md/raid:%s: Disk failure on %s, disabling device.\n"
2696 "md/raid:%s: Operation continuing on %d devices.\n",
2697 mdname(mddev),
2698 bdevname(rdev->bdev, b),
2699 mdname(mddev),
2700 conf->raid_disks - mddev->degraded);
70d466f7 2701 r5c_update_on_rdev_error(mddev, rdev);
16a53ecc 2702}
1da177e4
LT		 2703
2704/*
2705 * Input: a 'big' sector number,
2706 * Output: index of the data and parity disk, and the sector # in them.
2707 */
6d036f7d
SL		 2708sector_t raid5_compute_sector(struct r5conf *conf, sector_t r_sector,
2709 int previous, int *dd_idx,
2710 struct stripe_head *sh)
1da177e4 2711{
6e3b96ed 2712 sector_t stripe, stripe2;
35f2a591 2713 sector_t chunk_number;
1da177e4 2714 unsigned int chunk_offset;
911d4ee8 2715 int pd_idx, qd_idx;
67cc2b81 2716 int ddf_layout = 0;
1da177e4 2717 sector_t new_sector;
e183eaed
N		 2718 int algorithm = previous ? conf->prev_algo
2719 : conf->algorithm;
09c9e5fa
AN		 2720 int sectors_per_chunk = previous ? conf->prev_chunk_sectors
2721 : conf->chunk_sectors;
112bf897
N		 2722 int raid_disks = previous ? conf->previous_raid_disks
2723 : conf->raid_disks;
2724 int data_disks = raid_disks - conf->max_degraded;
1da177e4
LT		 2725
2726 /* First compute the information on this sector */
2727
2728 /*
2729 * Compute the chunk number and the sector offset inside the chunk
2730 */
2731 chunk_offset = sector_div(r_sector, sectors_per_chunk);
2732 chunk_number = r_sector;
1da177e4
LT		 2733
2734 /*
2735 * Compute the stripe number
2736 */
35f2a591
N		 2737 stripe = chunk_number;
2738 *dd_idx = sector_div(stripe, data_disks);
6e3b96ed 2739 stripe2 = stripe;
1da177e4
LT		 2740 /*
2741 * Select the parity disk based on the user selected algorithm.
2742 */
84789554 2743 pd_idx = qd_idx = -1;
16a53ecc
N		 2744 switch(conf->level) {
2745 case 4:
911d4ee8 2746 pd_idx = data_disks;
16a53ecc
N		 2747 break;
2748 case 5:
e183eaed 2749 switch (algorithm) {
1da177e4 2750 case ALGORITHM_LEFT_ASYMMETRIC:
6e3b96ed 2751 pd_idx = data_disks - sector_div(stripe2, raid_disks);
911d4ee8 2752 if (*dd_idx >= pd_idx)
1da177e4
LT		 2753 (*dd_idx)++;
2754 break;
2755 case ALGORITHM_RIGHT_ASYMMETRIC:
6e3b96ed 2756 pd_idx = sector_div(stripe2, raid_disks);
911d4ee8 2757 if (*dd_idx >= pd_idx)
1da177e4
LT		 2758 (*dd_idx)++;
2759 break;
2760 case ALGORITHM_LEFT_SYMMETRIC:
6e3b96ed 2761 pd_idx = data_disks - sector_div(stripe2, raid_disks);
911d4ee8 2762 *dd_idx = (pd_idx + 1 + *dd_idx) % raid_disks;
1da177e4
LT		 2763 break;
2764 case ALGORITHM_RIGHT_SYMMETRIC:
6e3b96ed 2765 pd_idx = sector_div(stripe2, raid_disks);
911d4ee8 2766 *dd_idx = (pd_idx + 1 + *dd_idx) % raid_disks;
1da177e4 2767 break;
99c0fb5f
N		 2768 case ALGORITHM_PARITY_0:
2769 pd_idx = 0;
2770 (*dd_idx)++;
2771 break;
2772 case ALGORITHM_PARITY_N:
2773 pd_idx = data_disks;
2774 break;
1da177e4 2775 default:
99c0fb5f 2776 BUG();
16a53ecc
N		 2777 }
2778 break;
2779 case 6:
2780
e183eaed 2781 switch (algorithm) {
16a53ecc 2782 case ALGORITHM_LEFT_ASYMMETRIC:
6e3b96ed 2783 pd_idx = raid_disks - 1 - sector_div(stripe2, raid_disks);
911d4ee8
N		 2784 qd_idx = pd_idx + 1;
2785 if (pd_idx == raid_disks-1) {
99c0fb5f 2786 (*dd_idx)++; /* Q D D D P */
911d4ee8
N		 2787 qd_idx = 0;
2788 } else if (*dd_idx >= pd_idx)
16a53ecc
N		 2789 (*dd_idx) += 2; /* D D P Q D */
2790 break;
2791 case ALGORITHM_RIGHT_ASYMMETRIC:
6e3b96ed 2792 pd_idx = sector_div(stripe2, raid_disks);
911d4ee8
N		 2793 qd_idx = pd_idx + 1;
2794 if (pd_idx == raid_disks-1) {
99c0fb5f 2795 (*dd_idx)++; /* Q D D D P */
911d4ee8
N		 2796 qd_idx = 0;
2797 } else if (*dd_idx >= pd_idx)
16a53ecc
N		 2798 (*dd_idx) += 2; /* D D P Q D */
2799 break;
2800 case ALGORITHM_LEFT_SYMMETRIC:
6e3b96ed 2801 pd_idx = raid_disks - 1 - sector_div(stripe2, raid_disks);
911d4ee8
N		 2802 qd_idx = (pd_idx + 1) % raid_disks;
2803 *dd_idx = (pd_idx + 2 + *dd_idx) % raid_disks;
16a53ecc
N		 2804 break;
2805 case ALGORITHM_RIGHT_SYMMETRIC:
6e3b96ed 2806 pd_idx = sector_div(stripe2, raid_disks);
911d4ee8
N		 2807 qd_idx = (pd_idx + 1) % raid_disks;
2808 *dd_idx = (pd_idx + 2 + *dd_idx) % raid_disks;
16a53ecc 2809 break;
99c0fb5f
N		 2810
2811 case ALGORITHM_PARITY_0:
2812 pd_idx = 0;
2813 qd_idx = 1;
2814 (*dd_idx) += 2;
2815 break;
2816 case ALGORITHM_PARITY_N:
2817 pd_idx = data_disks;
2818 qd_idx = data_disks + 1;
2819 break;
2820
2821 case ALGORITHM_ROTATING_ZERO_RESTART:
2822 /* Exactly the same as RIGHT_ASYMMETRIC, but or
2823 * of blocks for computing Q is different.
2824 */
6e3b96ed 2825 pd_idx = sector_div(stripe2, raid_disks);
99c0fb5f
N		 2826 qd_idx = pd_idx + 1;
2827 if (pd_idx == raid_disks-1) {
2828 (*dd_idx)++; /* Q D D D P */
2829 qd_idx = 0;
2830 } else if (*dd_idx >= pd_idx)
2831 (*dd_idx) += 2; /* D D P Q D */
67cc2b81 2832 ddf_layout = 1;
99c0fb5f
N		 2833 break;
2834
2835 case ALGORITHM_ROTATING_N_RESTART:
2836 /* Same a left_asymmetric, by first stripe is
2837 * D D D P Q rather than
2838 * Q D D D P
2839 */
6e3b96ed
N		 2840 stripe2 += 1;
2841 pd_idx = raid_disks - 1 - sector_div(stripe2, raid_disks);
99c0fb5f
N		 2842 qd_idx = pd_idx + 1;
2843 if (pd_idx == raid_disks-1) {
2844 (*dd_idx)++; /* Q D D D P */
2845 qd_idx = 0;
2846 } else if (*dd_idx >= pd_idx)
2847 (*dd_idx) += 2; /* D D P Q D */
67cc2b81 2848 ddf_layout = 1;
99c0fb5f
N		 2849 break;
2850
2851 case ALGORITHM_ROTATING_N_CONTINUE:
2852 /* Same as left_symmetric but Q is before P */
6e3b96ed 2853 pd_idx = raid_disks - 1 - sector_div(stripe2, raid_disks);
99c0fb5f
N		 2854 qd_idx = (pd_idx + raid_disks - 1) % raid_disks;
2855 *dd_idx = (pd_idx + 1 + *dd_idx) % raid_disks;
67cc2b81 2856 ddf_layout = 1;
99c0fb5f
N		 2857 break;
2858
2859 case ALGORITHM_LEFT_ASYMMETRIC_6:
2860 /* RAID5 left_asymmetric, with Q on last device */
6e3b96ed 2861 pd_idx = data_disks - sector_div(stripe2, raid_disks-1);
99c0fb5f
N		 2862 if (*dd_idx >= pd_idx)
2863 (*dd_idx)++;
2864 qd_idx = raid_disks - 1;
2865 break;
2866
2867 case ALGORITHM_RIGHT_ASYMMETRIC_6:
6e3b96ed 2868 pd_idx = sector_div(stripe2, raid_disks-1);
99c0fb5f
N		 2869 if (*dd_idx >= pd_idx)
2870 (*dd_idx)++;
2871 qd_idx = raid_disks - 1;
2872 break;
2873
2874 case ALGORITHM_LEFT_SYMMETRIC_6:
6e3b96ed 2875 pd_idx = data_disks - sector_div(stripe2, raid_disks-1);
99c0fb5f
N		 2876 *dd_idx = (pd_idx + 1 + *dd_idx) % (raid_disks-1);
2877 qd_idx = raid_disks - 1;
2878 break;
2879
2880 case ALGORITHM_RIGHT_SYMMETRIC_6:
6e3b96ed 2881 pd_idx = sector_div(stripe2, raid_disks-1);
99c0fb5f
N		 2882 *dd_idx = (pd_idx + 1 + *dd_idx) % (raid_disks-1);
2883 qd_idx = raid_disks - 1;
2884 break;
2885
2886 case ALGORITHM_PARITY_0_6:
2887 pd_idx = 0;
2888 (*dd_idx)++;
2889 qd_idx = raid_disks - 1;
2890 break;
2891
16a53ecc 2892 default:
99c0fb5f 2893 BUG();
16a53ecc
N		 2894 }
2895 break;
1da177e4
LT		 2896 }
2897
911d4ee8
N		 2898 if (sh) {
2899 sh->pd_idx = pd_idx;
2900 sh->qd_idx = qd_idx;
67cc2b81 2901 sh->ddf_layout = ddf_layout;
911d4ee8 2902 }
1da177e4
LT		 2903 /*
2904 * Finally, compute the new sector number
2905 */
2906 new_sector = (sector_t)stripe * sectors_per_chunk + chunk_offset;
2907 return new_sector;
2908}
2909
6d036f7d 2910sector_t raid5_compute_blocknr(struct stripe_head *sh, int i, int previous)
1da177e4 2911{
d1688a6d 2912 struct r5conf *conf = sh->raid_conf;
b875e531
N		 2913 int raid_disks = sh->disks;
2914 int data_disks = raid_disks - conf->max_degraded;
1da177e4 2915 sector_t new_sector = sh->sector, check;
09c9e5fa
AN		 2916 int sectors_per_chunk = previous ? conf->prev_chunk_sectors
2917 : conf->chunk_sectors;
e183eaed
N		 2918 int algorithm = previous ? conf->prev_algo
2919 : conf->algorithm;
1da177e4
LT		 2920 sector_t stripe;
2921 int chunk_offset;
35f2a591
N		 2922 sector_t chunk_number;
2923 int dummy1, dd_idx = i;
1da177e4 2924 sector_t r_sector;
911d4ee8 2925 struct stripe_head sh2;
1da177e4
LT		 2926
2927 chunk_offset = sector_div(new_sector, sectors_per_chunk);
2928 stripe = new_sector;
1da177e4 2929
16a53ecc
N		 2930 if (i == sh->pd_idx)
2931 return 0;
2932 switch(conf->level) {
2933 case 4: break;
2934 case 5:
e183eaed 2935 switch (algorithm) {
1da177e4
LT		 2936 case ALGORITHM_LEFT_ASYMMETRIC:
2937 case ALGORITHM_RIGHT_ASYMMETRIC:
2938 if (i > sh->pd_idx)
2939 i--;
2940 break;
2941 case ALGORITHM_LEFT_SYMMETRIC:
2942 case ALGORITHM_RIGHT_SYMMETRIC:
2943 if (i < sh->pd_idx)
2944 i += raid_disks;
2945 i -= (sh->pd_idx + 1);
2946 break;
99c0fb5f
N		 2947 case ALGORITHM_PARITY_0:
2948 i -= 1;
2949 break;
2950 case ALGORITHM_PARITY_N:
2951 break;
1da177e4 2952 default:
99c0fb5f 2953 BUG();
16a53ecc
N		 2954 }
2955 break;
2956 case 6:
d0dabf7e 2957 if (i == sh->qd_idx)
16a53ecc 2958 return 0; /* It is the Q disk */
e183eaed 2959 switch (algorithm) {
16a53ecc
N		 2960 case ALGORITHM_LEFT_ASYMMETRIC:
2961 case ALGORITHM_RIGHT_ASYMMETRIC:
99c0fb5f
N		 2962 case ALGORITHM_ROTATING_ZERO_RESTART:
2963 case ALGORITHM_ROTATING_N_RESTART:
2964 if (sh->pd_idx == raid_disks-1)
2965 i--; /* Q D D D P */
16a53ecc
N		 2966 else if (i > sh->pd_idx)
2967 i -= 2; /* D D P Q D */
2968 break;
2969 case ALGORITHM_LEFT_SYMMETRIC:
2970 case ALGORITHM_RIGHT_SYMMETRIC:
2971 if (sh->pd_idx == raid_disks-1)
2972 i--; /* Q D D D P */
2973 else {
2974 /* D D P Q D */
2975 if (i < sh->pd_idx)
2976 i += raid_disks;
2977 i -= (sh->pd_idx + 2);
2978 }
2979 break;
99c0fb5f
N		 2980 case ALGORITHM_PARITY_0:
2981 i -= 2;
2982 break;
2983 case ALGORITHM_PARITY_N:
2984 break;
2985 case ALGORITHM_ROTATING_N_CONTINUE:
e4424fee 2986 /* Like left_symmetric, but P is before Q */
99c0fb5f
N		 2987 if (sh->pd_idx == 0)
2988 i--; /* P D D D Q */
e4424fee
N		 2989 else {
2990 /* D D Q P D */
2991 if (i < sh->pd_idx)
2992 i += raid_disks;
2993 i -= (sh->pd_idx + 1);
2994 }
99c0fb5f
N		 2995 break;
2996 case ALGORITHM_LEFT_ASYMMETRIC_6:
2997 case ALGORITHM_RIGHT_ASYMMETRIC_6:
2998 if (i > sh->pd_idx)
2999 i--;
3000 break;
3001 case ALGORITHM_LEFT_SYMMETRIC_6:
3002 case ALGORITHM_RIGHT_SYMMETRIC_6:
3003 if (i < sh->pd_idx)
3004 i += data_disks + 1;
3005 i -= (sh->pd_idx + 1);
3006 break;
3007 case ALGORITHM_PARITY_0_6:
3008 i -= 1;
3009 break;
16a53ecc 3010 default:
99c0fb5f 3011 BUG();
16a53ecc
N		 3012 }
3013 break;
1da177e4
LT		 3014 }
3015
3016 chunk_number = stripe * data_disks + i;
35f2a591 3017 r_sector = chunk_number * sectors_per_chunk + chunk_offset;
1da177e4 3018
112bf897 3019 check = raid5_compute_sector(conf, r_sector,
784052ec 3020 previous, &dummy1, &sh2);
911d4ee8
N		 3021 if (check != sh->sector || dummy1 != dd_idx || sh2.pd_idx != sh->pd_idx
3022 || sh2.qd_idx != sh->qd_idx) {
cc6167b4
N		 3023 pr_warn("md/raid:%s: compute_blocknr: map not correct\n",
3024 mdname(conf->mddev));
1da177e4
LT		 3025 return 0;
3026 }
3027 return r_sector;
3028}
3029
07e83364
SL		 3030/*
3031 * There are cases where we want handle_stripe_dirtying() and
3032 * schedule_reconstruction() to delay towrite to some dev of a stripe.
3033 *
3034 * This function checks whether we want to delay the towrite. Specifically,
3035 * we delay the towrite when:
3036 *
3037 * 1. degraded stripe has a non-overwrite to the missing dev, AND this
3038 * stripe has data in journal (for other devices).
3039 *
3040 * In this case, when reading data for the non-overwrite dev, it is
3041 * necessary to handle complex rmw of write back cache (prexor with
3042 * orig_page, and xor with page). To keep read path simple, we would
3043 * like to flush data in journal to RAID disks first, so complex rmw
3044 * is handled in the write patch (handle_stripe_dirtying).
3045 *
39b99586
SL		 3046 * 2. when journal space is critical (R5C_LOG_CRITICAL=1)
3047 *
3048 * It is important to be able to flush all stripes in raid5-cache.
3049 * Therefore, we need reserve some space on the journal device for
3050 * these flushes. If flush operation includes pending writes to the
3051 * stripe, we need to reserve (conf->raid_disk + 1) pages per stripe
3052 * for the flush out. If we exclude these pending writes from flush
3053 * operation, we only need (conf->max_degraded + 1) pages per stripe.
3054 * Therefore, excluding pending writes in these cases enables more
3055 * efficient use of the journal device.
3056 *
3057 * Note: To make sure the stripe makes progress, we only delay
3058 * towrite for stripes with data already in journal (injournal > 0).
3059 * When LOG_CRITICAL, stripes with injournal == 0 will be sent to
3060 * no_space_stripes list.
3061 *
70d466f7
SL		 3062 * 3. during journal failure
3063 * In journal failure, we try to flush all cached data to raid disks
3064 * based on data in stripe cache. The array is read-only to upper
3065 * layers, so we would skip all pending writes.
3066 *
07e83364 3067 */
39b99586
SL		 3068static inline bool delay_towrite(struct r5conf *conf,
3069 struct r5dev *dev,
3070 struct stripe_head_state *s)
07e83364 3071{
39b99586
SL		 3072 /* case 1 above */
3073 if (!test_bit(R5_OVERWRITE, &dev->flags) &&
3074 !test_bit(R5_Insync, &dev->flags) && s->injournal)
3075 return true;
3076 /* case 2 above */
3077 if (test_bit(R5C_LOG_CRITICAL, &conf->cache_state) &&
3078 s->injournal > 0)
3079 return true;
70d466f7
SL		 3080 /* case 3 above */
3081 if (s->log_failed && s->injournal)
3082 return true;
39b99586 3083 return false;
07e83364
SL		 3084}
3085
600aa109 3086static void
c0f7bddb 3087schedule_reconstruction(struct stripe_head *sh, struct stripe_head_state *s,
600aa109 3088 int rcw, int expand)
e33129d8 3089{
584acdd4 3090 int i, pd_idx = sh->pd_idx, qd_idx = sh->qd_idx, disks = sh->disks;
d1688a6d 3091 struct r5conf *conf = sh->raid_conf;
c0f7bddb 3092 int level = conf->level;
e33129d8
DW		 3093
3094 if (rcw) {
1e6d690b
SL		 3095 /*
3096 * In some cases, handle_stripe_dirtying initially decided to
3097 * run rmw and allocates extra page for prexor. However, rcw is
3098 * cheaper later on. We need to free the extra page now,
3099 * because we won't be able to do that in ops_complete_prexor().
3100 */
3101 r5c_release_extra_page(sh);
e33129d8
DW		 3102
3103 for (i = disks; i--; ) {
3104 struct r5dev *dev = &sh->dev[i];
3105
39b99586 3106 if (dev->towrite && !delay_towrite(conf, dev, s)) {
e33129d8 3107 set_bit(R5_LOCKED, &dev->flags);
d8ee0728 3108 set_bit(R5_Wantdrain, &dev->flags);
e33129d8
DW		 3109 if (!expand)
3110 clear_bit(R5_UPTODATE, &dev->flags);
600aa109 3111 s->locked++;
1e6d690b
SL		 3112 } else if (test_bit(R5_InJournal, &dev->flags)) {
3113 set_bit(R5_LOCKED, &dev->flags);
3114 s->locked++;
e33129d8
DW		 3115 }
3116 }
ce7d363a
N		 3117 /* if we are not expanding this is a proper write request, and
3118 * there will be bios with new data to be drained into the
3119 * stripe cache
3120 */
3121 if (!expand) {
3122 if (!s->locked)
3123 /* False alarm, nothing to do */
3124 return;
3125 sh->reconstruct_state = reconstruct_state_drain_run;
3126 set_bit(STRIPE_OP_BIODRAIN, &s->ops_request);
3127 } else
3128 sh->reconstruct_state = reconstruct_state_run;
3129
3130 set_bit(STRIPE_OP_RECONSTRUCT, &s->ops_request);
3131
c0f7bddb 3132 if (s->locked + conf->max_degraded == disks)
8b3e6cdc 3133 if (!test_and_set_bit(STRIPE_FULL_WRITE, &sh->state))
c0f7bddb 3134 atomic_inc(&conf->pending_full_writes);
e33129d8
DW		 3135 } else {
3136 BUG_ON(!(test_bit(R5_UPTODATE, &sh->dev[pd_idx].flags) ||
3137 test_bit(R5_Wantcompute, &sh->dev[pd_idx].flags)));
584acdd4
MS		 3138 BUG_ON(level == 6 &&
3139 (!(test_bit(R5_UPTODATE, &sh->dev[qd_idx].flags) ||
3140 test_bit(R5_Wantcompute, &sh->dev[qd_idx].flags))));
e33129d8 3141
e33129d8
DW		 3142 for (i = disks; i--; ) {
3143 struct r5dev *dev = &sh->dev[i];
584acdd4 3144 if (i == pd_idx || i == qd_idx)
e33129d8
DW		 3145 continue;
3146
e33129d8
DW		 3147 if (dev->towrite &&
3148 (test_bit(R5_UPTODATE, &dev->flags) ||
d8ee0728
DW		 3149 test_bit(R5_Wantcompute, &dev->flags))) {
3150 set_bit(R5_Wantdrain, &dev->flags);
e33129d8
DW		 3151 set_bit(R5_LOCKED, &dev->flags);
3152 clear_bit(R5_UPTODATE, &dev->flags);
600aa109 3153 s->locked++;
1e6d690b
SL		 3154 } else if (test_bit(R5_InJournal, &dev->flags)) {
3155 set_bit(R5_LOCKED, &dev->flags);
3156 s->locked++;
e33129d8
DW		 3157 }
3158 }
ce7d363a
N		 3159 if (!s->locked)
3160 /* False alarm - nothing to do */
3161 return;
3162 sh->reconstruct_state = reconstruct_state_prexor_drain_run;
3163 set_bit(STRIPE_OP_PREXOR, &s->ops_request);
3164 set_bit(STRIPE_OP_BIODRAIN, &s->ops_request);
3165 set_bit(STRIPE_OP_RECONSTRUCT, &s->ops_request);
e33129d8
DW		 3166 }
3167
c0f7bddb 3168 /* keep the parity disk(s) locked while asynchronous operations
e33129d8
DW		 3169 * are in flight
3170 */
3171 set_bit(R5_LOCKED, &sh->dev[pd_idx].flags);
3172 clear_bit(R5_UPTODATE, &sh->dev[pd_idx].flags);
600aa109 3173 s->locked++;
e33129d8 3174
c0f7bddb
YT		 3175 if (level == 6) {
3176 int qd_idx = sh->qd_idx;
3177 struct r5dev *dev = &sh->dev[qd_idx];
3178
3179 set_bit(R5_LOCKED, &dev->flags);
3180 clear_bit(R5_UPTODATE, &dev->flags);
3181 s->locked++;
3182 }
3183
845b9e22 3184 if (raid5_has_ppl(sh->raid_conf) && sh->ppl_page &&
3418d036
AP		 3185 test_bit(STRIPE_OP_BIODRAIN, &s->ops_request) &&
3186 !test_bit(STRIPE_FULL_WRITE, &sh->state) &&
3187 test_bit(R5_Insync, &sh->dev[pd_idx].flags))
3188 set_bit(STRIPE_OP_PARTIAL_PARITY, &s->ops_request);
3189
600aa109 3190 pr_debug("%s: stripe %llu locked: %d ops_request: %lx\n",
e46b272b 3191 __func__, (unsigned long long)sh->sector,
600aa109 3192 s->locked, s->ops_request);
e33129d8 3193}
16a53ecc 3194
1da177e4
LT		 3195/*
3196 * Each stripe/dev can have one or more bion attached.
16a53ecc 3197 * toread/towrite point to the first in a chain.
1da177e4
LT		 3198 * The bi_next chain must be in order.
3199 */
da41ba65 3200static int add_stripe_bio(struct stripe_head *sh, struct bio *bi, int dd_idx,
3201 int forwrite, int previous)
1da177e4
LT		 3202{
3203 struct bio **bip;
d1688a6d 3204 struct r5conf *conf = sh->raid_conf;
72626685 3205 int firstwrite=0;
1da177e4 3206
cbe47ec5 3207 pr_debug("adding bi b#%llu to stripe s#%llu\n",
4f024f37 3208 (unsigned long long)bi->bi_iter.bi_sector,
1da177e4
LT		 3209 (unsigned long long)sh->sector);
3210
b17459c0 3211 spin_lock_irq(&sh->stripe_lock);
2cd259a7 3212 sh->dev[dd_idx].write_hint = bi->bi_write_hint;
59fc630b 3213 /* Don't allow new IO added to stripes in batch list */
3214 if (sh->batch_head)
3215 goto overlap;
72626685 3216 if (forwrite) {
1da177e4 3217 bip = &sh->dev[dd_idx].towrite;
7eaf7e8e 3218 if (*bip == NULL)
72626685
N		 3219 firstwrite = 1;
3220 } else
1da177e4 3221 bip = &sh->dev[dd_idx].toread;
4f024f37
KO		 3222 while (*bip && (*bip)->bi_iter.bi_sector < bi->bi_iter.bi_sector) {
3223 if (bio_end_sector(*bip) > bi->bi_iter.bi_sector)
1da177e4
LT		 3224 goto overlap;
3225 bip = & (*bip)->bi_next;
3226 }
4f024f37 3227 if (*bip && (*bip)->bi_iter.bi_sector < bio_end_sector(bi))
1da177e4
LT		 3228 goto overlap;
3229
3418d036
AP		 3230 if (forwrite && raid5_has_ppl(conf)) {
3231 /*
3232 * With PPL only writes to consecutive data chunks within a
3233 * stripe are allowed because for a single stripe_head we can
3234 * only have one PPL entry at a time, which describes one data
3235 * range. Not really an overlap, but wait_for_overlap can be
3236 * used to handle this.
3237 */
3238 sector_t sector;
3239 sector_t first = 0;
3240 sector_t last = 0;
3241 int count = 0;
3242 int i;
3243
3244 for (i = 0; i < sh->disks; i++) {
3245 if (i != sh->pd_idx &&
3246 (i == dd_idx || sh->dev[i].towrite)) {
3247 sector = sh->dev[i].sector;
3248 if (count == 0 || sector < first)
3249 first = sector;
3250 if (sector > last)
3251 last = sector;
3252 count++;
3253 }
3254 }
3255
3256 if (first + conf->chunk_sectors * (count - 1) != last)
3257 goto overlap;
3258 }
3259
da41ba65 3260 if (!forwrite || previous)
3261 clear_bit(STRIPE_BATCH_READY, &sh->state);
3262
78bafebd 3263 BUG_ON(*bip && bi->bi_next && (*bip) != bi->bi_next);
1da177e4
LT		 3264 if (*bip)
3265 bi->bi_next = *bip;
3266 *bip = bi;
016c76ac 3267 bio_inc_remaining(bi);
49728050 3268 md_write_inc(conf->mddev, bi);
72626685 3269
1da177e4
LT		 3270 if (forwrite) {
3271 /* check if page is covered */
3272 sector_t sector = sh->dev[dd_idx].sector;
3273 for (bi=sh->dev[dd_idx].towrite;
3274 sector < sh->dev[dd_idx].sector + STRIPE_SECTORS &&
4f024f37 3275 bi && bi->bi_iter.bi_sector <= sector;
1da177e4 3276 bi = r5_next_bio(bi, sh->dev[dd_idx].sector)) {
f73a1c7d
KO		 3277 if (bio_end_sector(bi) >= sector)
3278 sector = bio_end_sector(bi);
1da177e4
LT		 3279 }
3280 if (sector >= sh->dev[dd_idx].sector + STRIPE_SECTORS)
7a87f434 3281 if (!test_and_set_bit(R5_OVERWRITE, &sh->dev[dd_idx].flags))
3282 sh->overwrite_disks++;
1da177e4 3283 }
cbe47ec5
N		 3284
3285 pr_debug("added bi b#%llu to stripe s#%llu, disk %d.\n",
4f024f37 3286 (unsigned long long)(*bip)->bi_iter.bi_sector,
cbe47ec5
N		 3287 (unsigned long long)sh->sector, dd_idx);
3288
3289 if (conf->mddev->bitmap && firstwrite) {
d0852df5
N		 3290 /* Cannot hold spinlock over bitmap_startwrite,
3291 * but must ensure this isn't added to a batch until
3292 * we have added to the bitmap and set bm_seq.
3293 * So set STRIPE_BITMAP_PENDING to prevent
3294 * batching.
3295 * If multiple add_stripe_bio() calls race here they
3296 * much all set STRIPE_BITMAP_PENDING. So only the first one
3297 * to complete "bitmap_startwrite" gets to set
3298 * STRIPE_BIT_DELAY. This is important as once a stripe
3299 * is added to a batch, STRIPE_BIT_DELAY cannot be changed
3300 * any more.
3301 */
3302 set_bit(STRIPE_BITMAP_PENDING, &sh->state);
3303 spin_unlock_irq(&sh->stripe_lock);
cbe47ec5
N		 3304 bitmap_startwrite(conf->mddev->bitmap, sh->sector,
3305 STRIPE_SECTORS, 0);
d0852df5
N		 3306 spin_lock_irq(&sh->stripe_lock);
3307 clear_bit(STRIPE_BITMAP_PENDING, &sh->state);
3308 if (!sh->batch_head) {
3309 sh->bm_seq = conf->seq_flush+1;
3310 set_bit(STRIPE_BIT_DELAY, &sh->state);
3311 }
cbe47ec5 3312 }
d0852df5 3313 spin_unlock_irq(&sh->stripe_lock);
59fc630b 3314
3315 if (stripe_can_batch(sh))
3316 stripe_add_to_batch_list(conf, sh);
1da177e4
LT		 3317 return 1;
3318
3319 overlap:
3320 set_bit(R5_Overlap, &sh->dev[dd_idx].flags);
b17459c0 3321 spin_unlock_irq(&sh->stripe_lock);
1da177e4
LT		 3322 return 0;
3323}
3324
d1688a6d 3325static void end_reshape(struct r5conf *conf);
29269553 3326
d1688a6d 3327static void stripe_set_idx(sector_t stripe, struct r5conf *conf, int previous,
911d4ee8 3328 struct stripe_head *sh)
ccfcc3c1 3329{
784052ec 3330 int sectors_per_chunk =
09c9e5fa 3331 previous ? conf->prev_chunk_sectors : conf->chunk_sectors;
911d4ee8 3332 int dd_idx;
2d2063ce 3333 int chunk_offset = sector_div(stripe, sectors_per_chunk);
112bf897 3334 int disks = previous ? conf->previous_raid_disks : conf->raid_disks;
2d2063ce 3335
112bf897
N		 3336 raid5_compute_sector(conf,
3337 stripe * (disks - conf->max_degraded)
b875e531 3338 *sectors_per_chunk + chunk_offset,
112bf897 3339 previous,
911d4ee8 3340 &dd_idx, sh);
ccfcc3c1
N		 3341}
3342
a4456856 3343static void
d1688a6d 3344handle_failed_stripe(struct r5conf *conf, struct stripe_head *sh,
bd83d0a2 3345 struct stripe_head_state *s, int disks)
a4456856
DW		 3346{
3347 int i;
59fc630b 3348 BUG_ON(sh->batch_head);
a4456856
DW		 3349 for (i = disks; i--; ) {
3350 struct bio *bi;
3351 int bitmap_end = 0;
3352
3353 if (test_bit(R5_ReadError, &sh->dev[i].flags)) {
3cb03002 3354 struct md_rdev *rdev;
a4456856
DW		 3355 rcu_read_lock();
3356 rdev = rcu_dereference(conf->disks[i].rdev);
f5b67ae8
N		 3357 if (rdev && test_bit(In_sync, &rdev->flags) &&
3358 !test_bit(Faulty, &rdev->flags))
7f0da59b
N		 3359 atomic_inc(&rdev->nr_pending);
3360 else
3361 rdev = NULL;
a4456856 3362 rcu_read_unlock();
7f0da59b
N		 3363 if (rdev) {
3364 if (!rdev_set_badblocks(
3365 rdev,
3366 sh->sector,
3367 STRIPE_SECTORS, 0))
3368 md_error(conf->mddev, rdev);
3369 rdev_dec_pending(rdev, conf->mddev);
3370 }
a4456856 3371 }
b17459c0 3372 spin_lock_irq(&sh->stripe_lock);
a4456856
DW		 3373 /* fail all writes first */
3374 bi = sh->dev[i].towrite;
3375 sh->dev[i].towrite = NULL;
7a87f434 3376 sh->overwrite_disks = 0;
b17459c0 3377 spin_unlock_irq(&sh->stripe_lock);
1ed850f3 3378 if (bi)
a4456856 3379 bitmap_end = 1;
a4456856 3380
ff875738 3381 log_stripe_write_finished(sh);
0576b1c6 3382
a4456856
DW		 3383 if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags))
3384 wake_up(&conf->wait_for_overlap);
3385
4f024f37 3386 while (bi && bi->bi_iter.bi_sector <
a4456856
DW		 3387 sh->dev[i].sector + STRIPE_SECTORS) {
3388 struct bio *nextbi = r5_next_bio(bi, sh->dev[i].sector);
4246a0b6 3389
49728050 3390 md_write_end(conf->mddev);
6308d8e3 3391 bio_io_error(bi);
a4456856
DW		 3392 bi = nextbi;
3393 }
7eaf7e8e
SL		 3394 if (bitmap_end)
3395 bitmap_endwrite(conf->mddev->bitmap, sh->sector,
3396 STRIPE_SECTORS, 0, 0);
3397 bitmap_end = 0;
a4456856
DW		 3398 /* and fail all 'written' */
3399 bi = sh->dev[i].written;
3400 sh->dev[i].written = NULL;
d592a996
SL		 3401 if (test_and_clear_bit(R5_SkipCopy, &sh->dev[i].flags)) {
3402 WARN_ON(test_bit(R5_UPTODATE, &sh->dev[i].flags));
3403 sh->dev[i].page = sh->dev[i].orig_page;
3404 }
3405
a4456856 3406 if (bi) bitmap_end = 1;
4f024f37 3407 while (bi && bi->bi_iter.bi_sector <
a4456856
DW		 3408 sh->dev[i].sector + STRIPE_SECTORS) {
3409 struct bio *bi2 = r5_next_bio(bi, sh->dev[i].sector);
4246a0b6 3410
49728050 3411 md_write_end(conf->mddev);
6308d8e3 3412 bio_io_error(bi);
a4456856
DW		 3413 bi = bi2;
3414 }
3415
b5e98d65
DW		 3416 /* fail any reads if this device is non-operational and
3417 * the data has not reached the cache yet.
3418 */
3419 if (!test_bit(R5_Wantfill, &sh->dev[i].flags) &&
6e74a9cf 3420 s->failed > conf->max_degraded &&
b5e98d65
DW		 3421 (!test_bit(R5_Insync, &sh->dev[i].flags) ||
3422 test_bit(R5_ReadError, &sh->dev[i].flags))) {
143c4d05 3423 spin_lock_irq(&sh->stripe_lock);
a4456856
DW		 3424 bi = sh->dev[i].toread;
3425 sh->dev[i].toread = NULL;
143c4d05 3426 spin_unlock_irq(&sh->stripe_lock);
a4456856
DW		 3427 if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags))
3428 wake_up(&conf->wait_for_overlap);
ebda780b
SL		 3429 if (bi)
3430 s->to_read--;
4f024f37 3431 while (bi && bi->bi_iter.bi_sector <
a4456856
DW		 3432 sh->dev[i].sector + STRIPE_SECTORS) {
3433 struct bio *nextbi =
3434 r5_next_bio(bi, sh->dev[i].sector);
4246a0b6 3435
6308d8e3 3436 bio_io_error(bi);
a4456856
DW		 3437 bi = nextbi;
3438 }
3439 }
a4456856
DW		 3440 if (bitmap_end)
3441 bitmap_endwrite(conf->mddev->bitmap, sh->sector,
3442 STRIPE_SECTORS, 0, 0);
8cfa7b0f
N		 3443 /* If we were in the middle of a write the parity block might
3444 * still be locked - so just clear all R5_LOCKED flags
3445 */
3446 clear_bit(R5_LOCKED, &sh->dev[i].flags);
a4456856 3447 }
ebda780b
SL		 3448 s->to_write = 0;
3449 s->written = 0;
a4456856 3450
8b3e6cdc
DW		 3451 if (test_and_clear_bit(STRIPE_FULL_WRITE, &sh->state))
3452 if (atomic_dec_and_test(&conf->pending_full_writes))
3453 md_wakeup_thread(conf->mddev->thread);
a4456856
DW		 3454}
3455
7f0da59b 3456static void
d1688a6d 3457handle_failed_sync(struct r5conf *conf, struct stripe_head *sh,
7f0da59b
N		 3458 struct stripe_head_state *s)
3459{
3460 int abort = 0;
3461 int i;
3462
59fc630b 3463 BUG_ON(sh->batch_head);
7f0da59b 3464 clear_bit(STRIPE_SYNCING, &sh->state);
f8dfcffd
N		 3465 if (test_and_clear_bit(R5_Overlap, &sh->dev[sh->pd_idx].flags))
3466 wake_up(&conf->wait_for_overlap);
7f0da59b 3467 s->syncing = 0;
9a3e1101 3468 s->replacing = 0;
7f0da59b 3469 /* There is nothing more to do for sync/check/repair.
18b9837e
N		 3470 * Don't even need to abort as that is handled elsewhere
3471 * if needed, and not always wanted e.g. if there is a known
3472 * bad block here.
9a3e1101 3473 * For recover/replace we need to record a bad block on all
7f0da59b
N		 3474 * non-sync devices, or abort the recovery
3475 */
18b9837e
N		 3476 if (test_bit(MD_RECOVERY_RECOVER, &conf->mddev->recovery)) {
3477 /* During recovery devices cannot be removed, so
3478 * locking and refcounting of rdevs is not needed
3479 */
e50d3992 3480 rcu_read_lock();
18b9837e 3481 for (i = 0; i < conf->raid_disks; i++) {
e50d3992 3482 struct md_rdev *rdev = rcu_dereference(conf->disks[i].rdev);
18b9837e
N		 3483 if (rdev
3484 && !test_bit(Faulty, &rdev->flags)
3485 && !test_bit(In_sync, &rdev->flags)
3486 && !rdev_set_badblocks(rdev, sh->sector,
3487 STRIPE_SECTORS, 0))
3488 abort = 1;
e50d3992 3489 rdev = rcu_dereference(conf->disks[i].replacement);
18b9837e
N		 3490 if (rdev
3491 && !test_bit(Faulty, &rdev->flags)
3492 && !test_bit(In_sync, &rdev->flags)
3493 && !rdev_set_badblocks(rdev, sh->sector,
3494 STRIPE_SECTORS, 0))
3495 abort = 1;
3496 }
e50d3992 3497 rcu_read_unlock();
18b9837e
N		 3498 if (abort)
3499 conf->recovery_disabled =
3500 conf->mddev->recovery_disabled;
7f0da59b 3501 }
18b9837e 3502 md_done_sync(conf->mddev, STRIPE_SECTORS, !abort);
7f0da59b
N		 3503}
3504
9a3e1101
N		 3505static int want_replace(struct stripe_head *sh, int disk_idx)
3506{
3507 struct md_rdev *rdev;
3508 int rv = 0;
3f232d6a
N		 3509
3510 rcu_read_lock();
3511 rdev = rcu_dereference(sh->raid_conf->disks[disk_idx].replacement);
9a3e1101
N		 3512 if (rdev
3513 && !test_bit(Faulty, &rdev->flags)
3514 && !test_bit(In_sync, &rdev->flags)
3515 && (rdev->recovery_offset <= sh->sector
3516 || rdev->mddev->recovery_cp <= sh->sector))
3517 rv = 1;
3f232d6a 3518 rcu_read_unlock();
9a3e1101
N		 3519 return rv;
3520}
3521
2c58f06e
N		 3522static int need_this_block(struct stripe_head *sh, struct stripe_head_state *s,
3523 int disk_idx, int disks)
a4456856 3524{
5599becc 3525 struct r5dev *dev = &sh->dev[disk_idx];
f2b3b44d
N		 3526 struct r5dev *fdev[2] = { &sh->dev[s->failed_num[0]],
3527 &sh->dev[s->failed_num[1]] };
ea664c82 3528 int i;
5599becc 3529
a79cfe12
N		 3530
3531 if (test_bit(R5_LOCKED, &dev->flags) ||
3532 test_bit(R5_UPTODATE, &dev->flags))
3533 /* No point reading this as we already have it or have
3534 * decided to get it.
3535 */
3536 return 0;
3537
3538 if (dev->toread ||
3539 (dev->towrite && !test_bit(R5_OVERWRITE, &dev->flags)))
3540 /* We need this block to directly satisfy a request */
3541 return 1;
3542
3543 if (s->syncing || s->expanding ||
3544 (s->replacing && want_replace(sh, disk_idx)))
3545 /* When syncing, or expanding we read everything.
3546 * When replacing, we need the replaced block.
3547 */
3548 return 1;
3549
3550 if ((s->failed >= 1 && fdev[0]->toread) ||
3551 (s->failed >= 2 && fdev[1]->toread))
3552 /* If we want to read from a failed device, then
3553 * we need to actually read every other device.
3554 */
3555 return 1;
3556
a9d56950
N		 3557 /* Sometimes neither read-modify-write nor reconstruct-write
3558 * cycles can work. In those cases we read every block we
3559 * can. Then the parity-update is certain to have enough to
3560 * work with.
3561 * This can only be a problem when we need to write something,
3562 * and some device has failed. If either of those tests
3563 * fail we need look no further.
3564 */
3565 if (!s->failed || !s->to_write)
3566 return 0;
3567
3568 if (test_bit(R5_Insync, &dev->flags) &&
3569 !test_bit(STRIPE_PREREAD_ACTIVE, &sh->state))
3570 /* Pre-reads at not permitted until after short delay
3571 * to gather multiple requests. However if this
3560741e 3572 * device is no Insync, the block could only be computed
a9d56950
N		 3573 * and there is no need to delay that.
3574 */
3575 return 0;
ea664c82 3576
36707bb2 3577 for (i = 0; i < s->failed && i < 2; i++) {
ea664c82
N		 3578 if (fdev[i]->towrite &&
3579 !test_bit(R5_UPTODATE, &fdev[i]->flags) &&
3580 !test_bit(R5_OVERWRITE, &fdev[i]->flags))
3581 /* If we have a partial write to a failed
3582 * device, then we will need to reconstruct
3583 * the content of that device, so all other
3584 * devices must be read.
3585 */
3586 return 1;
3587 }
3588
3589 /* If we are forced to do a reconstruct-write, either because
3590 * the current RAID6 implementation only supports that, or
3560741e 3591 * because parity cannot be trusted and we are currently
ea664c82
N		 3592 * recovering it, there is extra need to be careful.
3593 * If one of the devices that we would need to read, because
3594 * it is not being overwritten (and maybe not written at all)
3595 * is missing/faulty, then we need to read everything we can.
3596 */
3597 if (sh->raid_conf->level != 6 &&
3598 sh->sector < sh->raid_conf->mddev->recovery_cp)
3599 /* reconstruct-write isn't being forced */
3600 return 0;
36707bb2 3601 for (i = 0; i < s->failed && i < 2; i++) {
10d82c5f
N		 3602 if (s->failed_num[i] != sh->pd_idx &&
3603 s->failed_num[i] != sh->qd_idx &&
3604 !test_bit(R5_UPTODATE, &fdev[i]->flags) &&
ea664c82
N		 3605 !test_bit(R5_OVERWRITE, &fdev[i]->flags))
3606 return 1;
3607 }
3608
2c58f06e
N		 3609 return 0;
3610}
3611
ba02684d
SL		 3612/* fetch_block - checks the given member device to see if its data needs
3613 * to be read or computed to satisfy a request.
3614 *
3615 * Returns 1 when no more member devices need to be checked, otherwise returns
3616 * 0 to tell the loop in handle_stripe_fill to continue
3617 */
2c58f06e
N		 3618static int fetch_block(struct stripe_head *sh, struct stripe_head_state *s,
3619 int disk_idx, int disks)
3620{
3621 struct r5dev *dev = &sh->dev[disk_idx];
3622
3623 /* is the data in this block needed, and can we get it? */
3624 if (need_this_block(sh, s, disk_idx, disks)) {
5599becc
YT		 3625 /* we would like to get this block, possibly by computing it,
3626 * otherwise read it if the backing disk is insync
3627 */
3628 BUG_ON(test_bit(R5_Wantcompute, &dev->flags));
3629 BUG_ON(test_bit(R5_Wantread, &dev->flags));
b0c783b3 3630 BUG_ON(sh->batch_head);
7471fb77
N		 3631
3632 /*
3633 * In the raid6 case if the only non-uptodate disk is P
3634 * then we already trusted P to compute the other failed
3635 * drives. It is safe to compute rather than re-read P.
3636 * In other cases we only compute blocks from failed
3637 * devices, otherwise check/repair might fail to detect
3638 * a real inconsistency.
3639 */
3640
5599becc 3641 if ((s->uptodate == disks - 1) &&
7471fb77 3642 ((sh->qd_idx >= 0 && sh->pd_idx == disk_idx) ||
f2b3b44d 3643 (s->failed && (disk_idx == s->failed_num[0] ||
7471fb77 3644 disk_idx == s->failed_num[1])))) {
5599becc
YT		 3645 /* have disk failed, and we're requested to fetch it;
3646 * do compute it
a4456856 3647 */
5599becc
YT		 3648 pr_debug("Computing stripe %llu block %d\n",
3649 (unsigned long long)sh->sector, disk_idx);
3650 set_bit(STRIPE_COMPUTE_RUN, &sh->state);
3651 set_bit(STRIPE_OP_COMPUTE_BLK, &s->ops_request);
3652 set_bit(R5_Wantcompute, &dev->flags);
3653 sh->ops.target = disk_idx;
3654 sh->ops.target2 = -1; /* no 2nd target */
3655 s->req_compute = 1;
93b3dbce
N		 3656 /* Careful: from this point on 'uptodate' is in the eye
3657 * of raid_run_ops which services 'compute' operations
3658 * before writes. R5_Wantcompute flags a block that will
3659 * be R5_UPTODATE by the time it is needed for a
3660 * subsequent operation.
3661 */
5599becc
YT		 3662 s->uptodate++;
3663 return 1;
3664 } else if (s->uptodate == disks-2 && s->failed >= 2) {
3665 /* Computing 2-failure is *very* expensive; only
3666 * do it if failed >= 2
3667 */
3668 int other;
3669 for (other = disks; other--; ) {
3670 if (other == disk_idx)
3671 continue;
3672 if (!test_bit(R5_UPTODATE,
3673 &sh->dev[other].flags))
3674 break;
a4456856 3675 }
5599becc
YT		 3676 BUG_ON(other < 0);
3677 pr_debug("Computing stripe %llu blocks %d,%d\n",
3678 (unsigned long long)sh->sector,
3679 disk_idx, other);
3680 set_bit(STRIPE_COMPUTE_RUN, &sh->state);
3681 set_bit(STRIPE_OP_COMPUTE_BLK, &s->ops_request);
3682 set_bit(R5_Wantcompute, &sh->dev[disk_idx].flags);
3683 set_bit(R5_Wantcompute, &sh->dev[other].flags);
3684 sh->ops.target = disk_idx;
3685 sh->ops.target2 = other;
3686 s->uptodate += 2;
3687 s->req_compute = 1;
3688 return 1;
3689 } else if (test_bit(R5_Insync, &dev->flags)) {
3690 set_bit(R5_LOCKED, &dev->flags);
3691 set_bit(R5_Wantread, &dev->flags);
3692 s->locked++;
3693 pr_debug("Reading block %d (sync=%d)\n",
3694 disk_idx, s->syncing);
a4456856
DW		 3695 }
3696 }
5599becc
YT		 3697
3698 return 0;
3699}
3700
3701/**
93b3dbce 3702 * handle_stripe_fill - read or compute data to satisfy pending requests.
5599becc 3703 */
93b3dbce
N		 3704static void handle_stripe_fill(struct stripe_head *sh,
3705 struct stripe_head_state *s,
3706 int disks)
5599becc
YT		 3707{
3708 int i;
3709
3710 /* look for blocks to read/compute, skip this if a compute
3711 * is already in flight, or if the stripe contents are in the
3712 * midst of changing due to a write
3713 */
3714 if (!test_bit(STRIPE_COMPUTE_RUN, &sh->state) && !sh->check_state &&
07e83364
SL		 3715 !sh->reconstruct_state) {
3716
3717 /*
3718 * For degraded stripe with data in journal, do not handle
3719 * read requests yet, instead, flush the stripe to raid
3720 * disks first, this avoids handling complex rmw of write
3721 * back cache (prexor with orig_page, and then xor with
3722 * page) in the read path
3723 */
3724 if (s->injournal && s->failed) {
3725 if (test_bit(STRIPE_R5C_CACHING, &sh->state))
3726 r5c_make_stripe_write_out(sh);
3727 goto out;
3728 }
3729
5599becc 3730 for (i = disks; i--; )
93b3dbce 3731 if (fetch_block(sh, s, i, disks))
5599becc 3732 break;
07e83364
SL		 3733 }
3734out:
a4456856
DW		 3735 set_bit(STRIPE_HANDLE, &sh->state);
3736}
3737
787b76fa
N		 3738static void break_stripe_batch_list(struct stripe_head *head_sh,
3739 unsigned long handle_flags);
1fe797e6 3740/* handle_stripe_clean_event
a4456856
DW		 3741 * any written block on an uptodate or failed drive can be returned.
3742 * Note that if we 'wrote' to a failed drive, it will be UPTODATE, but
3743 * never LOCKED, so we don't need to test 'failed' directly.
3744 */
d1688a6d 3745static void handle_stripe_clean_event(struct r5conf *conf,
bd83d0a2 3746 struct stripe_head *sh, int disks)
a4456856
DW		 3747{
3748 int i;
3749 struct r5dev *dev;
f8dfcffd 3750 int discard_pending = 0;
59fc630b 3751 struct stripe_head *head_sh = sh;
3752 bool do_endio = false;
a4456856
DW		 3753
3754 for (i = disks; i--; )
3755 if (sh->dev[i].written) {
3756 dev = &sh->dev[i];
3757 if (!test_bit(R5_LOCKED, &dev->flags) &&
9e444768 3758 (test_bit(R5_UPTODATE, &dev->flags) ||
d592a996
SL		 3759 test_bit(R5_Discard, &dev->flags) ||
3760 test_bit(R5_SkipCopy, &dev->flags))) {
a4456856
DW		 3761 /* We can return any write requests */
3762 struct bio *wbi, *wbi2;
45b4233c 3763 pr_debug("Return write for disc %d\n", i);
ca64cae9
N		 3764 if (test_and_clear_bit(R5_Discard, &dev->flags))
3765 clear_bit(R5_UPTODATE, &dev->flags);
d592a996
SL		 3766 if (test_and_clear_bit(R5_SkipCopy, &dev->flags)) {
3767 WARN_ON(test_bit(R5_UPTODATE, &dev->flags));
d592a996 3768 }
59fc630b 3769 do_endio = true;
3770
3771returnbi:
3772 dev->page = dev->orig_page;
a4456856
DW		 3773 wbi = dev->written;
3774 dev->written = NULL;
4f024f37 3775 while (wbi && wbi->bi_iter.bi_sector <
a4456856
DW		 3776 dev->sector + STRIPE_SECTORS) {
3777 wbi2 = r5_next_bio(wbi, dev->sector);
49728050 3778 md_write_end(conf->mddev);
016c76ac 3779 bio_endio(wbi);
a4456856
DW		 3780 wbi = wbi2;
3781 }
7eaf7e8e
SL		 3782 bitmap_endwrite(conf->mddev->bitmap, sh->sector,
3783 STRIPE_SECTORS,
a4456856 3784 !test_bit(STRIPE_DEGRADED, &sh->state),
7eaf7e8e 3785 0);
59fc630b 3786 if (head_sh->batch_head) {
3787 sh = list_first_entry(&sh->batch_list,
3788 struct stripe_head,
3789 batch_list);
3790 if (sh != head_sh) {
3791 dev = &sh->dev[i];
3792 goto returnbi;
3793 }
3794 }
3795 sh = head_sh;
3796 dev = &sh->dev[i];
f8dfcffd
N		 3797 } else if (test_bit(R5_Discard, &dev->flags))
3798 discard_pending = 1;
3799 }
f6bed0ef 3800
ff875738 3801 log_stripe_write_finished(sh);
0576b1c6 3802
f8dfcffd
N		 3803 if (!discard_pending &&
3804 test_bit(R5_Discard, &sh->dev[sh->pd_idx].flags)) {
b8a9d66d 3805 int hash;
f8dfcffd
N		 3806 clear_bit(R5_Discard, &sh->dev[sh->pd_idx].flags);
3807 clear_bit(R5_UPTODATE, &sh->dev[sh->pd_idx].flags);
3808 if (sh->qd_idx >= 0) {
3809 clear_bit(R5_Discard, &sh->dev[sh->qd_idx].flags);
3810 clear_bit(R5_UPTODATE, &sh->dev[sh->qd_idx].flags);
3811 }
3812 /* now that discard is done we can proceed with any sync */
3813 clear_bit(STRIPE_DISCARD, &sh->state);
d47648fc
SL		 3814 /*
3815 * SCSI discard will change some bio fields and the stripe has
3816 * no updated data, so remove it from hash list and the stripe
3817 * will be reinitialized
3818 */
59fc630b 3819unhash:
b8a9d66d
RG		 3820 hash = sh->hash_lock_index;
3821 spin_lock_irq(conf->hash_locks + hash);
d47648fc 3822 remove_hash(sh);
b8a9d66d 3823 spin_unlock_irq(conf->hash_locks + hash);
59fc630b 3824 if (head_sh->batch_head) {
3825 sh = list_first_entry(&sh->batch_list,
3826 struct stripe_head, batch_list);
3827 if (sh != head_sh)
3828 goto unhash;
3829 }
59fc630b 3830 sh = head_sh;
3831
f8dfcffd
N		 3832 if (test_bit(STRIPE_SYNC_REQUESTED, &sh->state))
3833 set_bit(STRIPE_HANDLE, &sh->state);
3834
3835 }
8b3e6cdc
DW		 3836
3837 if (test_and_clear_bit(STRIPE_FULL_WRITE, &sh->state))
3838 if (atomic_dec_and_test(&conf->pending_full_writes))
3839 md_wakeup_thread(conf->mddev->thread);
59fc630b 3840
787b76fa
N		 3841 if (head_sh->batch_head && do_endio)
3842 break_stripe_batch_list(head_sh, STRIPE_EXPAND_SYNC_FLAGS);
a4456856
DW		 3843}
3844
86aa1397
SL		 3845/*
3846 * For RMW in write back cache, we need extra page in prexor to store the
3847 * old data. This page is stored in dev->orig_page.
3848 *
3849 * This function checks whether we have data for prexor. The exact logic
3850 * is:
3851 * R5_UPTODATE && (!R5_InJournal || R5_OrigPageUPTDODATE)
3852 */
3853static inline bool uptodate_for_rmw(struct r5dev *dev)
3854{
3855 return (test_bit(R5_UPTODATE, &dev->flags)) &&
3856 (!test_bit(R5_InJournal, &dev->flags) ||
3857 test_bit(R5_OrigPageUPTDODATE, &dev->flags));
3858}
3859
d7bd398e
SL		 3860static int handle_stripe_dirtying(struct r5conf *conf,
3861 struct stripe_head *sh,
3862 struct stripe_head_state *s,
3863 int disks)
a4456856
DW		 3864{
3865 int rmw = 0, rcw = 0, i;
a7854487
AL		 3866 sector_t recovery_cp = conf->mddev->recovery_cp;
3867
584acdd4 3868 /* Check whether resync is now happening or should start.
a7854487
AL		 3869 * If yes, then the array is dirty (after unclean shutdown or
3870 * initial creation), so parity in some stripes might be inconsistent.
3871 * In this case, we need to always do reconstruct-write, to ensure
3872 * that in case of drive failure or read-error correction, we
3873 * generate correct data from the parity.
3874 */
584acdd4 3875 if (conf->rmw_level == PARITY_DISABLE_RMW ||
26ac1073
N		 3876 (recovery_cp < MaxSector && sh->sector >= recovery_cp &&
3877 s->failed == 0)) {
a7854487 3878 /* Calculate the real rcw later - for now make it
c8ac1803
N		 3879 * look like rcw is cheaper
3880 */
3881 rcw = 1; rmw = 2;
584acdd4
MS		 3882 pr_debug("force RCW rmw_level=%u, recovery_cp=%llu sh->sector=%llu\n",
3883 conf->rmw_level, (unsigned long long)recovery_cp,
a7854487 3884 (unsigned long long)sh->sector);
c8ac1803 3885 } else for (i = disks; i--; ) {
a4456856
DW		 3886 /* would I have to read this buffer for read_modify_write */
3887 struct r5dev *dev = &sh->dev[i];
39b99586 3888 if (((dev->towrite && !delay_towrite(conf, dev, s)) ||
07e83364 3889 i == sh->pd_idx || i == sh->qd_idx ||
1e6d690b 3890 test_bit(R5_InJournal, &dev->flags)) &&
a4456856 3891 !test_bit(R5_LOCKED, &dev->flags) &&
86aa1397 3892 !(uptodate_for_rmw(dev) ||
f38e1219 3893 test_bit(R5_Wantcompute, &dev->flags))) {
a4456856
DW		 3894 if (test_bit(R5_Insync, &dev->flags))
3895 rmw++;
3896 else
3897 rmw += 2*disks; /* cannot read it */
3898 }
3899 /* Would I have to read this buffer for reconstruct_write */
584acdd4
MS		 3900 if (!test_bit(R5_OVERWRITE, &dev->flags) &&
3901 i != sh->pd_idx && i != sh->qd_idx &&
a4456856 3902 !test_bit(R5_LOCKED, &dev->flags) &&
f38e1219 3903 !(test_bit(R5_UPTODATE, &dev->flags) ||
1e6d690b 3904 test_bit(R5_Wantcompute, &dev->flags))) {
67f45548
N		 3905 if (test_bit(R5_Insync, &dev->flags))
3906 rcw++;
a4456856
DW		 3907 else
3908 rcw += 2*disks;
3909 }
3910 }
1e6d690b 3911
39b99586
SL		 3912 pr_debug("for sector %llu state 0x%lx, rmw=%d rcw=%d\n",
3913 (unsigned long long)sh->sector, sh->state, rmw, rcw);
a4456856 3914 set_bit(STRIPE_HANDLE, &sh->state);
41257580 3915 if ((rmw < rcw || (rmw == rcw && conf->rmw_level == PARITY_PREFER_RMW)) && rmw > 0) {
a4456856 3916 /* prefer read-modify-write, but need to get some data */
e3620a3a
JB		 3917 if (conf->mddev->queue)
3918 blk_add_trace_msg(conf->mddev->queue,
3919 "raid5 rmw %llu %d",
3920 (unsigned long long)sh->sector, rmw);
a4456856
DW		 3921 for (i = disks; i--; ) {
3922 struct r5dev *dev = &sh->dev[i];
1e6d690b
SL		 3923 if (test_bit(R5_InJournal, &dev->flags) &&
3924 dev->page == dev->orig_page &&
3925 !test_bit(R5_LOCKED, &sh->dev[sh->pd_idx].flags)) {
3926 /* alloc page for prexor */
d7bd398e
SL		 3927 struct page *p = alloc_page(GFP_NOIO);
3928
3929 if (p) {
3930 dev->orig_page = p;
3931 continue;
3932 }
3933
3934 /*
3935 * alloc_page() failed, try use
3936 * disk_info->extra_page
3937 */
3938 if (!test_and_set_bit(R5C_EXTRA_PAGE_IN_USE,
3939 &conf->cache_state)) {
3940 r5c_use_extra_page(sh);
3941 break;
3942 }
1e6d690b 3943
d7bd398e
SL		 3944 /* extra_page in use, add to delayed_list */
3945 set_bit(STRIPE_DELAYED, &sh->state);
3946 s->waiting_extra_page = 1;
3947 return -EAGAIN;
1e6d690b 3948 }
d7bd398e 3949 }
1e6d690b 3950
d7bd398e
SL		 3951 for (i = disks; i--; ) {
3952 struct r5dev *dev = &sh->dev[i];
39b99586 3953 if (((dev->towrite && !delay_towrite(conf, dev, s)) ||
1e6d690b
SL		 3954 i == sh->pd_idx || i == sh->qd_idx ||
3955 test_bit(R5_InJournal, &dev->flags)) &&
a4456856 3956 !test_bit(R5_LOCKED, &dev->flags) &&
86aa1397 3957 !(uptodate_for_rmw(dev) ||
1e6d690b 3958 test_bit(R5_Wantcompute, &dev->flags)) &&
a4456856 3959 test_bit(R5_Insync, &dev->flags)) {
67f45548
N		 3960 if (test_bit(STRIPE_PREREAD_ACTIVE,
3961 &sh->state)) {
3962 pr_debug("Read_old block %d for r-m-w\n",
3963 i);
a4456856
DW		 3964 set_bit(R5_LOCKED, &dev->flags);
3965 set_bit(R5_Wantread, &dev->flags);
3966 s->locked++;
3967 } else {
3968 set_bit(STRIPE_DELAYED, &sh->state);
3969 set_bit(STRIPE_HANDLE, &sh->state);
3970 }
3971 }
3972 }
a9add5d9 3973 }
41257580 3974 if ((rcw < rmw || (rcw == rmw && conf->rmw_level != PARITY_PREFER_RMW)) && rcw > 0) {
a4456856 3975 /* want reconstruct write, but need to get some data */
a9add5d9 3976 int qread =0;
c8ac1803 3977 rcw = 0;
a4456856
DW		 3978 for (i = disks; i--; ) {
3979 struct r5dev *dev = &sh->dev[i];
3980 if (!test_bit(R5_OVERWRITE, &dev->flags) &&
c8ac1803 3981 i != sh->pd_idx && i != sh->qd_idx &&
a4456856 3982 !test_bit(R5_LOCKED, &dev->flags) &&
f38e1219 3983 !(test_bit(R5_UPTODATE, &dev->flags) ||
c8ac1803
N		 3984 test_bit(R5_Wantcompute, &dev->flags))) {
3985 rcw++;
67f45548
N		 3986 if (test_bit(R5_Insync, &dev->flags) &&
3987 test_bit(STRIPE_PREREAD_ACTIVE,
3988 &sh->state)) {
45b4233c 3989 pr_debug("Read_old block "
a4456856
DW		 3990 "%d for Reconstruct\n", i);
3991 set_bit(R5_LOCKED, &dev->flags);
3992 set_bit(R5_Wantread, &dev->flags);
3993 s->locked++;
a9add5d9 3994 qread++;
a4456856
DW		 3995 } else {
3996 set_bit(STRIPE_DELAYED, &sh->state);
3997 set_bit(STRIPE_HANDLE, &sh->state);
3998 }
3999 }
4000 }
e3620a3a 4001 if (rcw && conf->mddev->queue)
a9add5d9
N		 4002 blk_add_trace_msg(conf->mddev->queue, "raid5 rcw %llu %d %d %d",
4003 (unsigned long long)sh->sector,
4004 rcw, qread, test_bit(STRIPE_DELAYED, &sh->state));
c8ac1803 4005 }
b1b02fe9
N		 4006
4007 if (rcw > disks && rmw > disks &&
4008 !test_bit(STRIPE_PREREAD_ACTIVE, &sh->state))
4009 set_bit(STRIPE_DELAYED, &sh->state);
4010
a4456856
DW		 4011 /* now if nothing is locked, and if we have enough data,
4012 * we can start a write request
4013 */
f38e1219
DW		 4014 /* since handle_stripe can be called at any time we need to handle the
4015 * case where a compute block operation has been submitted and then a
ac6b53b6
DW		 4016 * subsequent call wants to start a write request. raid_run_ops only
4017 * handles the case where compute block and reconstruct are requested
f38e1219
DW		 4018 * simultaneously. If this is not the case then new writes need to be
4019 * held off until the compute completes.
4020 */
976ea8d4
DW		 4021 if ((s->req_compute || !test_bit(STRIPE_COMPUTE_RUN, &sh->state)) &&
4022 (s->locked == 0 && (rcw == 0 || rmw == 0) &&
1e6d690b 4023 !test_bit(STRIPE_BIT_DELAY, &sh->state)))
c0f7bddb 4024 schedule_reconstruction(sh, s, rcw == 0, 0);
d7bd398e 4025 return 0;
a4456856
DW		 4026}
4027
d1688a6d 4028static void handle_parity_checks5(struct r5conf *conf, struct stripe_head *sh,
a4456856
DW		 4029 struct stripe_head_state *s, int disks)
4030{
ecc65c9b 4031 struct r5dev *dev = NULL;
bd2ab670 4032
59fc630b 4033 BUG_ON(sh->batch_head);
a4456856 4034 set_bit(STRIPE_HANDLE, &sh->state);
e89f8962 4035
ecc65c9b
DW		 4036 switch (sh->check_state) {
4037 case check_state_idle:
4038 /* start a new check operation if there are no failures */
bd2ab670 4039 if (s->failed == 0) {
bd2ab670 4040 BUG_ON(s->uptodate != disks);
ecc65c9b
DW		 4041 sh->check_state = check_state_run;
4042 set_bit(STRIPE_OP_CHECK, &s->ops_request);
bd2ab670 4043 clear_bit(R5_UPTODATE, &sh->dev[sh->pd_idx].flags);
bd2ab670 4044 s->uptodate--;
ecc65c9b 4045 break;
bd2ab670 4046 }
f2b3b44d 4047 dev = &sh->dev[s->failed_num[0]];
ecc65c9b
DW		 4048 /* fall through */
4049 case check_state_compute_result:
4050 sh->check_state = check_state_idle;
4051 if (!dev)
4052 dev = &sh->dev[sh->pd_idx];
4053
4054 /* check that a write has not made the stripe insync */
4055 if (test_bit(STRIPE_INSYNC, &sh->state))
4056 break;
c8894419 4057
a4456856 4058 /* either failed parity check, or recovery is happening */
a4456856
DW		 4059 BUG_ON(!test_bit(R5_UPTODATE, &dev->flags));
4060 BUG_ON(s->uptodate != disks);
4061
4062 set_bit(R5_LOCKED, &dev->flags);
ecc65c9b 4063 s->locked++;
a4456856 4064 set_bit(R5_Wantwrite, &dev->flags);
830ea016 4065
a4456856 4066 clear_bit(STRIPE_DEGRADED, &sh->state);
a4456856 4067 set_bit(STRIPE_INSYNC, &sh->state);
ecc65c9b
DW		 4068 break;
4069 case check_state_run:
4070 break; /* we will be called again upon completion */
4071 case check_state_check_result:
4072 sh->check_state = check_state_idle;
4073
4074 /* if a failure occurred during the check operation, leave
4075 * STRIPE_INSYNC not set and let the stripe be handled again
4076 */
4077 if (s->failed)
4078 break;
4079
4080 /* handle a successful check operation, if parity is correct
4081 * we are done. Otherwise update the mismatch count and repair
4082 * parity if !MD_RECOVERY_CHECK
4083 */
ad283ea4 4084 if ((sh->ops.zero_sum_result & SUM_CHECK_P_RESULT) == 0)
ecc65c9b
DW		 4085 /* parity is correct (on disc,
4086 * not in buffer any more)
4087 */
4088 set_bit(STRIPE_INSYNC, &sh->state);
4089 else {
7f7583d4 4090 atomic64_add(STRIPE_SECTORS, &conf->mddev->resync_mismatches);
e1539036 4091 if (test_bit(MD_RECOVERY_CHECK, &conf->mddev->recovery)) {
ecc65c9b
DW		 4092 /* don't try to repair!! */
4093 set_bit(STRIPE_INSYNC, &sh->state);
e1539036
N		 4094 pr_warn_ratelimited("%s: mismatch sector in range "
4095 "%llu-%llu\n", mdname(conf->mddev),
4096 (unsigned long long) sh->sector,
4097 (unsigned long long) sh->sector +
4098 STRIPE_SECTORS);
4099 } else {
ecc65c9b 4100 sh->check_state = check_state_compute_run;
976ea8d4 4101 set_bit(STRIPE_COMPUTE_RUN, &sh->state);
ecc65c9b
DW		 4102 set_bit(STRIPE_OP_COMPUTE_BLK, &s->ops_request);
4103 set_bit(R5_Wantcompute,
4104 &sh->dev[sh->pd_idx].flags);
4105 sh->ops.target = sh->pd_idx;
ac6b53b6 4106 sh->ops.target2 = -1;
ecc65c9b
DW		 4107 s->uptodate++;
4108 }
4109 }
4110 break;
4111 case check_state_compute_run:
4112 break;
4113 default:
cc6167b4 4114 pr_err("%s: unknown check_state: %d sector: %llu\n",
ecc65c9b
DW		 4115 __func__, sh->check_state,
4116 (unsigned long long) sh->sector);
4117 BUG();
a4456856
DW		 4118 }
4119}
4120
d1688a6d 4121static void handle_parity_checks6(struct r5conf *conf, struct stripe_head *sh,
36d1c647 4122 struct stripe_head_state *s,
f2b3b44d 4123 int disks)
a4456856 4124{
a4456856 4125 int pd_idx = sh->pd_idx;
34e04e87 4126 int qd_idx = sh->qd_idx;
d82dfee0 4127 struct r5dev *dev;
a4456856 4128
59fc630b 4129 BUG_ON(sh->batch_head);
a4456856
DW		 4130 set_bit(STRIPE_HANDLE, &sh->state);
4131
4132 BUG_ON(s->failed > 2);
d82dfee0 4133
a4456856
DW		 4134 /* Want to check and possibly repair P and Q.
4135 * However there could be one 'failed' device, in which
4136 * case we can only check one of them, possibly using the
4137 * other to generate missing data
4138 */
4139
d82dfee0
DW		 4140 switch (sh->check_state) {
4141 case check_state_idle:
4142 /* start a new check operation if there are < 2 failures */
f2b3b44d 4143 if (s->failed == s->q_failed) {
d82dfee0 4144 /* The only possible failed device holds Q, so it
a4456856
DW		 4145 * makes sense to check P (If anything else were failed,
4146 * we would have used P to recreate it).
4147 */
d82dfee0 4148 sh->check_state = check_state_run;
a4456856 4149 }
f2b3b44d 4150 if (!s->q_failed && s->failed < 2) {
d82dfee0 4151 /* Q is not failed, and we didn't use it to generate
a4456856
DW		 4152 * anything, so it makes sense to check it
4153 */
d82dfee0
DW		 4154 if (sh->check_state == check_state_run)
4155 sh->check_state = check_state_run_pq;
4156 else
4157 sh->check_state = check_state_run_q;
a4456856 4158 }
a4456856 4159
d82dfee0
DW		 4160 /* discard potentially stale zero_sum_result */
4161 sh->ops.zero_sum_result = 0;
a4456856 4162
d82dfee0
DW		 4163 if (sh->check_state == check_state_run) {
4164 /* async_xor_zero_sum destroys the contents of P */
4165 clear_bit(R5_UPTODATE, &sh->dev[pd_idx].flags);
4166 s->uptodate--;
a4456856 4167 }
d82dfee0
DW		 4168 if (sh->check_state >= check_state_run &&
4169 sh->check_state <= check_state_run_pq) {
4170 /* async_syndrome_zero_sum preserves P and Q, so
4171 * no need to mark them !uptodate here
4172 */
4173 set_bit(STRIPE_OP_CHECK, &s->ops_request);
4174 break;
a4456856
DW		 4175 }
4176
d82dfee0
DW		 4177 /* we have 2-disk failure */
4178 BUG_ON(s->failed != 2);
4179 /* fall through */
4180 case check_state_compute_result:
4181 sh->check_state = check_state_idle;
a4456856 4182
d82dfee0
DW		 4183 /* check that a write has not made the stripe insync */
4184 if (test_bit(STRIPE_INSYNC, &sh->state))
4185 break;
a4456856
DW		 4186
4187 /* now write out any block on a failed drive,
d82dfee0 4188 * or P or Q if they were recomputed
a4456856 4189 */
d82dfee0 4190 BUG_ON(s->uptodate < disks - 1); /* We don't need Q to recover */
a4456856 4191 if (s->failed == 2) {
f2b3b44d 4192 dev = &sh->dev[s->failed_num[1]];
a4456856
DW		 4193 s->locked++;
4194 set_bit(R5_LOCKED, &dev->flags);
4195 set_bit(R5_Wantwrite, &dev->flags);
4196 }
4197 if (s->failed >= 1) {
f2b3b44d 4198 dev = &sh->dev[s->failed_num[0]];
a4456856
DW		 4199 s->locked++;
4200 set_bit(R5_LOCKED, &dev->flags);
4201 set_bit(R5_Wantwrite, &dev->flags);
4202 }
d82dfee0 4203 if (sh->ops.zero_sum_result & SUM_CHECK_P_RESULT) {
a4456856
DW		 4204 dev = &sh->dev[pd_idx];
4205 s->locked++;
4206 set_bit(R5_LOCKED, &dev->flags);
4207 set_bit(R5_Wantwrite, &dev->flags);
4208 }
d82dfee0 4209 if (sh->ops.zero_sum_result & SUM_CHECK_Q_RESULT) {
a4456856
DW		 4210 dev = &sh->dev[qd_idx];
4211 s->locked++;
4212 set_bit(R5_LOCKED, &dev->flags);
4213 set_bit(R5_Wantwrite, &dev->flags);
4214 }
4215 clear_bit(STRIPE_DEGRADED, &sh->state);
4216
4217 set_bit(STRIPE_INSYNC, &sh->state);
d82dfee0
DW		 4218 break;
4219 case check_state_run:
4220 case check_state_run_q:
4221 case check_state_run_pq:
4222 break; /* we will be called again upon completion */
4223 case check_state_check_result:
4224 sh->check_state = check_state_idle;
4225
4226 /* handle a successful check operation, if parity is correct
4227 * we are done. Otherwise update the mismatch count and repair
4228 * parity if !MD_RECOVERY_CHECK
4229 */
4230 if (sh->ops.zero_sum_result == 0) {
4231 /* both parities are correct */
4232 if (!s->failed)
4233 set_bit(STRIPE_INSYNC, &sh->state);
4234 else {
4235 /* in contrast to the raid5 case we can validate
4236 * parity, but still have a failure to write
4237 * back
4238 */
4239 sh->check_state = check_state_compute_result;
4240 /* Returning at this point means that we may go
4241 * off and bring p and/or q uptodate again so
4242 * we make sure to check zero_sum_result again
4243 * to verify if p or q need writeback
4244 */
4245 }
4246 } else {
7f7583d4 4247 atomic64_add(STRIPE_SECTORS, &conf->mddev->resync_mismatches);
e1539036 4248 if (test_bit(MD_RECOVERY_CHECK, &conf->mddev->recovery)) {
d82dfee0
DW		 4249 /* don't try to repair!! */
4250 set_bit(STRIPE_INSYNC, &sh->state);
e1539036
N		 4251 pr_warn_ratelimited("%s: mismatch sector in range "
4252 "%llu-%llu\n", mdname(conf->mddev),
4253 (unsigned long long) sh->sector,
4254 (unsigned long long) sh->sector +
4255 STRIPE_SECTORS);
4256 } else {
d82dfee0
DW		 4257 int *target = &sh->ops.target;
4258
4259 sh->ops.target = -1;
4260 sh->ops.target2 = -1;
4261 sh->check_state = check_state_compute_run;
4262 set_bit(STRIPE_COMPUTE_RUN, &sh->state);
4263 set_bit(STRIPE_OP_COMPUTE_BLK, &s->ops_request);
4264 if (sh->ops.zero_sum_result & SUM_CHECK_P_RESULT) {
4265 set_bit(R5_Wantcompute,
4266 &sh->dev[pd_idx].flags);
4267 *target = pd_idx;
4268 target = &sh->ops.target2;
4269 s->uptodate++;
4270 }
4271 if (sh->ops.zero_sum_result & SUM_CHECK_Q_RESULT) {
4272 set_bit(R5_Wantcompute,
4273 &sh->dev[qd_idx].flags);
4274 *target = qd_idx;
4275 s->uptodate++;
4276 }
4277 }
4278 }
4279 break;
4280 case check_state_compute_run:
4281 break;
4282 default:
cc6167b4
N		 4283 pr_warn("%s: unknown check_state: %d sector: %llu\n",
4284 __func__, sh->check_state,
4285 (unsigned long long) sh->sector);
d82dfee0 4286 BUG();
a4456856
DW		 4287 }
4288}
4289
d1688a6d 4290static void handle_stripe_expansion(struct r5conf *conf, struct stripe_head *sh)
a4456856
DW		 4291{
4292 int i;
4293
4294 /* We have read all the blocks in this stripe and now we need to
4295 * copy some of them into a target stripe for expand.
4296 */
f0a50d37 4297 struct dma_async_tx_descriptor *tx = NULL;
59fc630b 4298 BUG_ON(sh->batch_head);
a4456856
DW		 4299 clear_bit(STRIPE_EXPAND_SOURCE, &sh->state);
4300 for (i = 0; i < sh->disks; i++)
34e04e87 4301 if (i != sh->pd_idx && i != sh->qd_idx) {
911d4ee8 4302 int dd_idx, j;
a4456856 4303 struct stripe_head *sh2;
a08abd8c 4304 struct async_submit_ctl submit;
a4456856 4305
6d036f7d 4306 sector_t bn = raid5_compute_blocknr(sh, i, 1);
911d4ee8
N		 4307 sector_t s = raid5_compute_sector(conf, bn, 0,
4308 &dd_idx, NULL);
6d036f7d 4309 sh2 = raid5_get_active_stripe(conf, s, 0, 1, 1);
a4456856
DW		 4310 if (sh2 == NULL)
4311 /* so far only the early blocks of this stripe
4312 * have been requested. When later blocks
4313 * get requested, we will try again
4314 */
4315 continue;
4316 if (!test_bit(STRIPE_EXPANDING, &sh2->state) ||
4317 test_bit(R5_Expanded, &sh2->dev[dd_idx].flags)) {
4318 /* must have already done this block */
6d036f7d 4319 raid5_release_stripe(sh2);
a4456856
DW		 4320 continue;
4321 }
f0a50d37
DW		 4322
4323 /* place all the copies on one channel */
a08abd8c 4324 init_async_submit(&submit, 0, tx, NULL, NULL, NULL);
f0a50d37 4325 tx = async_memcpy(sh2->dev[dd_idx].page,
88ba2aa5 4326 sh->dev[i].page, 0, 0, STRIPE_SIZE,
a08abd8c 4327 &submit);
f0a50d37 4328
a4456856
DW		 4329 set_bit(R5_Expanded, &sh2->dev[dd_idx].flags);
4330 set_bit(R5_UPTODATE, &sh2->dev[dd_idx].flags);
4331 for (j = 0; j < conf->raid_disks; j++)
4332 if (j != sh2->pd_idx &&
86c374ba 4333 j != sh2->qd_idx &&
a4456856
DW		 4334 !test_bit(R5_Expanded, &sh2->dev[j].flags))
4335 break;
4336 if (j == conf->raid_disks) {
4337 set_bit(STRIPE_EXPAND_READY, &sh2->state);
4338 set_bit(STRIPE_HANDLE, &sh2->state);
4339 }
6d036f7d 4340 raid5_release_stripe(sh2);
f0a50d37 4341
a4456856 4342 }
a2e08551 4343 /* done submitting copies, wait for them to complete */
749586b7 4344 async_tx_quiesce(&tx);
a4456856 4345}
1da177e4
LT		 4346
4347/*
4348 * handle_stripe - do things to a stripe.
4349 *
9a3e1101
N		 4350 * We lock the stripe by setting STRIPE_ACTIVE and then examine the
4351 * state of various bits to see what needs to be done.
1da177e4 4352 * Possible results:
9a3e1101
N		 4353 * return some read requests which now have data
4354 * return some write requests which are safely on storage
1da177e4
LT		 4355 * schedule a read on some buffers
4356 * schedule a write of some buffers
4357 * return confirmation of parity correctness
4358 *
1da177e4 4359 */
a4456856 4360
acfe726b 4361static void analyse_stripe(struct stripe_head *sh, struct stripe_head_state *s)
1da177e4 4362{
d1688a6d 4363 struct r5conf *conf = sh->raid_conf;
f416885e 4364 int disks = sh->disks;
474af965
N		 4365 struct r5dev *dev;
4366 int i;
9a3e1101 4367 int do_recovery = 0;
1da177e4 4368
acfe726b
N		 4369 memset(s, 0, sizeof(*s));
4370
dabc4ec6 4371 s->expanding = test_bit(STRIPE_EXPAND_SOURCE, &sh->state) && !sh->batch_head;
4372 s->expanded = test_bit(STRIPE_EXPAND_READY, &sh->state) && !sh->batch_head;
acfe726b
N		 4373 s->failed_num[0] = -1;
4374 s->failed_num[1] = -1;
6e74a9cf 4375 s->log_failed = r5l_log_disk_error(conf);
1da177e4 4376
acfe726b 4377 /* Now to look around and see what can be done */
1da177e4 4378 rcu_read_lock();
16a53ecc 4379 for (i=disks; i--; ) {
3cb03002 4380 struct md_rdev *rdev;
31c176ec
N		 4381 sector_t first_bad;
4382 int bad_sectors;
4383 int is_bad = 0;
acfe726b 4384
16a53ecc 4385 dev = &sh->dev[i];
1da177e4 4386
45b4233c 4387 pr_debug("check %d: state 0x%lx read %p write %p written %p\n",
9a3e1101
N		 4388 i, dev->flags,
4389 dev->toread, dev->towrite, dev->written);
6c0069c0
YT		 4390 /* maybe we can reply to a read
4391 *
4392 * new wantfill requests are only permitted while
4393 * ops_complete_biofill is guaranteed to be inactive
4394 */
4395 if (test_bit(R5_UPTODATE, &dev->flags) && dev->toread &&
4396 !test_bit(STRIPE_BIOFILL_RUN, &sh->state))
4397 set_bit(R5_Wantfill, &dev->flags);
1da177e4 4398
16a53ecc 4399 /* now count some things */
cc94015a
N		 4400 if (test_bit(R5_LOCKED, &dev->flags))
4401 s->locked++;
4402 if (test_bit(R5_UPTODATE, &dev->flags))
4403 s->uptodate++;
2d6e4ecc 4404 if (test_bit(R5_Wantcompute, &dev->flags)) {
cc94015a
N		 4405 s->compute++;
4406 BUG_ON(s->compute > 2);
2d6e4ecc 4407 }
1da177e4 4408
acfe726b 4409 if (test_bit(R5_Wantfill, &dev->flags))
cc94015a 4410 s->to_fill++;
acfe726b 4411 else if (dev->toread)
cc94015a 4412 s->to_read++;
16a53ecc 4413 if (dev->towrite) {
cc94015a 4414 s->to_write++;
16a53ecc 4415 if (!test_bit(R5_OVERWRITE, &dev->flags))
cc94015a 4416 s->non_overwrite++;
16a53ecc 4417 }
a4456856 4418 if (dev->written)
cc94015a 4419 s->written++;
14a75d3e
N		 4420 /* Prefer to use the replacement for reads, but only
4421 * if it is recovered enough and has no bad blocks.
4422 */
4423 rdev = rcu_dereference(conf->disks[i].replacement);
4424 if (rdev && !test_bit(Faulty, &rdev->flags) &&
4425 rdev->recovery_offset >= sh->sector + STRIPE_SECTORS &&
4426 !is_badblock(rdev, sh->sector, STRIPE_SECTORS,
4427 &first_bad, &bad_sectors))
4428 set_bit(R5_ReadRepl, &dev->flags);
4429 else {
e6030cb0 4430 if (rdev && !test_bit(Faulty, &rdev->flags))
9a3e1101 4431 set_bit(R5_NeedReplace, &dev->flags);
e6030cb0
N		 4432 else
4433 clear_bit(R5_NeedReplace, &dev->flags);
14a75d3e
N		 4434 rdev = rcu_dereference(conf->disks[i].rdev);
4435 clear_bit(R5_ReadRepl, &dev->flags);
4436 }
9283d8c5
N		 4437 if (rdev && test_bit(Faulty, &rdev->flags))
4438 rdev = NULL;
31c176ec
N		 4439 if (rdev) {
4440 is_bad = is_badblock(rdev, sh->sector, STRIPE_SECTORS,
4441 &first_bad, &bad_sectors);
4442 if (s->blocked_rdev == NULL
4443 && (test_bit(Blocked, &rdev->flags)
4444 || is_bad < 0)) {
4445 if (is_bad < 0)
4446 set_bit(BlockedBadBlocks,
4447 &rdev->flags);
4448 s->blocked_rdev = rdev;
4449 atomic_inc(&rdev->nr_pending);
4450 }
6bfe0b49 4451 }
415e72d0
N		 4452 clear_bit(R5_Insync, &dev->flags);
4453 if (!rdev)
4454 /* Not in-sync */;
31c176ec
N		 4455 else if (is_bad) {
4456 /* also not in-sync */
18b9837e
N		 4457 if (!test_bit(WriteErrorSeen, &rdev->flags) &&
4458 test_bit(R5_UPTODATE, &dev->flags)) {
31c176ec
N		 4459 /* treat as in-sync, but with a read error
4460 * which we can now try to correct
4461 */
4462 set_bit(R5_Insync, &dev->flags);
4463 set_bit(R5_ReadError, &dev->flags);
4464 }
4465 } else if (test_bit(In_sync, &rdev->flags))
415e72d0 4466 set_bit(R5_Insync, &dev->flags);
30d7a483 4467 else if (sh->sector + STRIPE_SECTORS <= rdev->recovery_offset)
415e72d0 4468 /* in sync if before recovery_offset */
30d7a483
N		 4469 set_bit(R5_Insync, &dev->flags);
4470 else if (test_bit(R5_UPTODATE, &dev->flags) &&
4471 test_bit(R5_Expanded, &dev->flags))
4472 /* If we've reshaped into here, we assume it is Insync.
4473 * We will shortly update recovery_offset to make
4474 * it official.
4475 */
4476 set_bit(R5_Insync, &dev->flags);
4477
1cc03eb9 4478 if (test_bit(R5_WriteError, &dev->flags)) {
14a75d3e
N		 4479 /* This flag does not apply to '.replacement'
4480 * only to .rdev, so make sure to check that*/
4481 struct md_rdev *rdev2 = rcu_dereference(
4482 conf->disks[i].rdev);
4483 if (rdev2 == rdev)
4484 clear_bit(R5_Insync, &dev->flags);
4485 if (rdev2 && !test_bit(Faulty, &rdev2->flags)) {
bc2607f3 4486 s->handle_bad_blocks = 1;
14a75d3e 4487 atomic_inc(&rdev2->nr_pending);
bc2607f3
N		 4488 } else
4489 clear_bit(R5_WriteError, &dev->flags);
4490 }
1cc03eb9 4491 if (test_bit(R5_MadeGood, &dev->flags)) {
14a75d3e
N		 4492 /* This flag does not apply to '.replacement'
4493 * only to .rdev, so make sure to check that*/
4494 struct md_rdev *rdev2 = rcu_dereference(
4495 conf->disks[i].rdev);
4496 if (rdev2 && !test_bit(Faulty, &rdev2->flags)) {
b84db560 4497 s->handle_bad_blocks = 1;
14a75d3e 4498 atomic_inc(&rdev2->nr_pending);
b84db560
N		 4499 } else
4500 clear_bit(R5_MadeGood, &dev->flags);
4501 }
977df362
N		 4502 if (test_bit(R5_MadeGoodRepl, &dev->flags)) {
4503 struct md_rdev *rdev2 = rcu_dereference(
4504 conf->disks[i].replacement);
4505 if (rdev2 && !test_bit(Faulty, &rdev2->flags)) {
4506 s->handle_bad_blocks = 1;
4507 atomic_inc(&rdev2->nr_pending);
4508 } else
4509 clear_bit(R5_MadeGoodRepl, &dev->flags);
4510 }
415e72d0 4511 if (!test_bit(R5_Insync, &dev->flags)) {
16a53ecc
N		 4512 /* The ReadError flag will just be confusing now */
4513 clear_bit(R5_ReadError, &dev->flags);
4514 clear_bit(R5_ReWrite, &dev->flags);
1da177e4 4515 }
415e72d0
N		 4516 if (test_bit(R5_ReadError, &dev->flags))
4517 clear_bit(R5_Insync, &dev->flags);
4518 if (!test_bit(R5_Insync, &dev->flags)) {
cc94015a
N		 4519 if (s->failed < 2)
4520 s->failed_num[s->failed] = i;
4521 s->failed++;
9a3e1101
N		 4522 if (rdev && !test_bit(Faulty, &rdev->flags))
4523 do_recovery = 1;
415e72d0 4524 }
2ded3703
SL		 4525
4526 if (test_bit(R5_InJournal, &dev->flags))
4527 s->injournal++;
1e6d690b
SL		 4528 if (test_bit(R5_InJournal, &dev->flags) && dev->written)
4529 s->just_cached++;
1da177e4 4530 }
9a3e1101
N		 4531 if (test_bit(STRIPE_SYNCING, &sh->state)) {
4532 /* If there is a failed device being replaced,
4533 * we must be recovering.
4534 * else if we are after recovery_cp, we must be syncing
c6d2e084 4535 * else if MD_RECOVERY_REQUESTED is set, we also are syncing.
9a3e1101
N		 4536 * else we can only be replacing
4537 * sync and recovery both need to read all devices, and so
4538 * use the same flag.
4539 */
4540 if (do_recovery ||
c6d2e084 4541 sh->sector >= conf->mddev->recovery_cp ||
4542 test_bit(MD_RECOVERY_REQUESTED, &(conf->mddev->recovery)))
9a3e1101
N		 4543 s->syncing = 1;
4544 else
4545 s->replacing = 1;
4546 }
1da177e4 4547 rcu_read_unlock();
cc94015a
N		 4548}
4549
59fc630b 4550static int clear_batch_ready(struct stripe_head *sh)
4551{
b15a9dbd
N		 4552 /* Return '1' if this is a member of batch, or
4553 * '0' if it is a lone stripe or a head which can now be
4554 * handled.
4555 */
59fc630b 4556 struct stripe_head *tmp;
4557 if (!test_and_clear_bit(STRIPE_BATCH_READY, &sh->state))
b15a9dbd 4558 return (sh->batch_head && sh->batch_head != sh);
59fc630b 4559 spin_lock(&sh->stripe_lock);
4560 if (!sh->batch_head) {
4561 spin_unlock(&sh->stripe_lock);
4562 return 0;
4563 }
4564
4565 /*
4566 * this stripe could be added to a batch list before we check
4567 * BATCH_READY, skips it
4568 */
4569 if (sh->batch_head != sh) {
4570 spin_unlock(&sh->stripe_lock);
4571 return 1;
4572 }
4573 spin_lock(&sh->batch_lock);
4574 list_for_each_entry(tmp, &sh->batch_list, batch_list)
4575 clear_bit(STRIPE_BATCH_READY, &tmp->state);
4576 spin_unlock(&sh->batch_lock);
4577 spin_unlock(&sh->stripe_lock);
4578
4579 /*
4580 * BATCH_READY is cleared, no new stripes can be added.
4581 * batch_list can be accessed without lock
4582 */
4583 return 0;
4584}
4585
3960ce79
N		 4586static void break_stripe_batch_list(struct stripe_head *head_sh,
4587 unsigned long handle_flags)
72ac7330 4588{
4e3d62ff 4589 struct stripe_head *sh, *next;
72ac7330 4590 int i;
fb642b92 4591 int do_wakeup = 0;
72ac7330 4592
bb27051f
N		 4593 list_for_each_entry_safe(sh, next, &head_sh->batch_list, batch_list) {
4594
72ac7330 4595 list_del_init(&sh->batch_list);
4596
fb3229d5 4597 WARN_ONCE(sh->state & ((1 << STRIPE_ACTIVE) |
1b956f7a
N		 4598 (1 << STRIPE_SYNCING) |
4599 (1 << STRIPE_REPLACED) |
1b956f7a
N		 4600 (1 << STRIPE_DELAYED) |
4601 (1 << STRIPE_BIT_DELAY) |
4602 (1 << STRIPE_FULL_WRITE) |
4603 (1 << STRIPE_BIOFILL_RUN) |
4604 (1 << STRIPE_COMPUTE_RUN) |
4605 (1 << STRIPE_OPS_REQ_PENDING) |
4606 (1 << STRIPE_DISCARD) |
4607 (1 << STRIPE_BATCH_READY) |
4608 (1 << STRIPE_BATCH_ERR) |
fb3229d5
SL		 4609 (1 << STRIPE_BITMAP_PENDING)),
4610 "stripe state: %lx\n", sh->state);
4611 WARN_ONCE(head_sh->state & ((1 << STRIPE_DISCARD) |
4612 (1 << STRIPE_REPLACED)),
4613 "head stripe state: %lx\n", head_sh->state);
1b956f7a
N		 4614
4615 set_mask_bits(&sh->state, ~(STRIPE_EXPAND_SYNC_FLAGS |
550da24f 4616 (1 << STRIPE_PREREAD_ACTIVE) |
184a09eb
DY		 4617 (1 << STRIPE_DEGRADED) |
4618 (1 << STRIPE_ON_UNPLUG_LIST)),
1b956f7a
N		 4619 head_sh->state & (1 << STRIPE_INSYNC));
4620
72ac7330 4621 sh->check_state = head_sh->check_state;
4622 sh->reconstruct_state = head_sh->reconstruct_state;
448ec638
AC		 4623 spin_lock_irq(&sh->stripe_lock);
4624 sh->batch_head = NULL;
4625 spin_unlock_irq(&sh->stripe_lock);
fb642b92
N		 4626 for (i = 0; i < sh->disks; i++) {
4627 if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags))
4628 do_wakeup = 1;
72ac7330 4629 sh->dev[i].flags = head_sh->dev[i].flags &
4630 (~((1 << R5_WriteError) | (1 << R5_Overlap)));
fb642b92 4631 }
3960ce79
N		 4632 if (handle_flags == 0 ||
4633 sh->state & handle_flags)
4634 set_bit(STRIPE_HANDLE, &sh->state);
6d036f7d 4635 raid5_release_stripe(sh);
72ac7330 4636 }
fb642b92
N		 4637 spin_lock_irq(&head_sh->stripe_lock);
4638 head_sh->batch_head = NULL;
4639 spin_unlock_irq(&head_sh->stripe_lock);
4640 for (i = 0; i < head_sh->disks; i++)
4641 if (test_and_clear_bit(R5_Overlap, &head_sh->dev[i].flags))
4642 do_wakeup = 1;
3960ce79
N		 4643 if (head_sh->state & handle_flags)
4644 set_bit(STRIPE_HANDLE, &head_sh->state);
fb642b92
N		 4645
4646 if (do_wakeup)
4647 wake_up(&head_sh->raid_conf->wait_for_overlap);
72ac7330 4648}
4649
cc94015a
N		 4650static void handle_stripe(struct stripe_head *sh)
4651{
4652 struct stripe_head_state s;
d1688a6d 4653 struct r5conf *conf = sh->raid_conf;
3687c061 4654 int i;
84789554
N		 4655 int prexor;
4656 int disks = sh->disks;
474af965 4657 struct r5dev *pdev, *qdev;
cc94015a
N		 4658
4659 clear_bit(STRIPE_HANDLE, &sh->state);
257a4b42 4660 if (test_and_set_bit_lock(STRIPE_ACTIVE, &sh->state)) {
cc94015a
N		 4661 /* already being handled, ensure it gets handled
4662 * again when current action finishes */
4663 set_bit(STRIPE_HANDLE, &sh->state);
4664 return;
4665 }
4666
59fc630b 4667 if (clear_batch_ready(sh) ) {
4668 clear_bit_unlock(STRIPE_ACTIVE, &sh->state);
4669 return;
4670 }
4671
4e3d62ff 4672 if (test_and_clear_bit(STRIPE_BATCH_ERR, &sh->state))
3960ce79 4673 break_stripe_batch_list(sh, 0);
72ac7330 4674
dabc4ec6 4675 if (test_bit(STRIPE_SYNC_REQUESTED, &sh->state) && !sh->batch_head) {
f8dfcffd 4676 spin_lock(&sh->stripe_lock);
5ddf0440
SL		 4677 /*
4678 * Cannot process 'sync' concurrently with 'discard'.
4679 * Flush data in r5cache before 'sync'.
4680 */
4681 if (!test_bit(STRIPE_R5C_PARTIAL_STRIPE, &sh->state) &&
4682 !test_bit(STRIPE_R5C_FULL_STRIPE, &sh->state) &&
4683 !test_bit(STRIPE_DISCARD, &sh->state) &&
f8dfcffd
N		 4684 test_and_clear_bit(STRIPE_SYNC_REQUESTED, &sh->state)) {
4685 set_bit(STRIPE_SYNCING, &sh->state);
4686 clear_bit(STRIPE_INSYNC, &sh->state);
f94c0b66 4687 clear_bit(STRIPE_REPLACED, &sh->state);
f8dfcffd
N		 4688 }
4689 spin_unlock(&sh->stripe_lock);
cc94015a
N		 4690 }
4691 clear_bit(STRIPE_DELAYED, &sh->state);
4692
4693 pr_debug("handling stripe %llu, state=%#lx cnt=%d, "
4694 "pd_idx=%d, qd_idx=%d\n, check:%d, reconstruct:%d\n",
4695 (unsigned long long)sh->sector, sh->state,
4696 atomic_read(&sh->count), sh->pd_idx, sh->qd_idx,
4697 sh->check_state, sh->reconstruct_state);
3687c061 4698
acfe726b 4699 analyse_stripe(sh, &s);
c5a31000 4700
b70abcb2
SL		 4701 if (test_bit(STRIPE_LOG_TRAPPED, &sh->state))
4702 goto finish;
4703
16d997b7
N		 4704 if (s.handle_bad_blocks ||
4705 test_bit(MD_SB_CHANGE_PENDING, &conf->mddev->sb_flags)) {
bc2607f3
N		 4706 set_bit(STRIPE_HANDLE, &sh->state);
4707 goto finish;
4708 }
4709
474af965
N		 4710 if (unlikely(s.blocked_rdev)) {
4711 if (s.syncing || s.expanding || s.expanded ||
9a3e1101 4712 s.replacing || s.to_write || s.written) {
474af965
N		 4713 set_bit(STRIPE_HANDLE, &sh->state);
4714 goto finish;
4715 }
4716 /* There is nothing for the blocked_rdev to block */
4717 rdev_dec_pending(s.blocked_rdev, conf->mddev);
4718 s.blocked_rdev = NULL;
4719 }
4720
4721 if (s.to_fill && !test_bit(STRIPE_BIOFILL_RUN, &sh->state)) {
4722 set_bit(STRIPE_OP_BIOFILL, &s.ops_request);
4723 set_bit(STRIPE_BIOFILL_RUN, &sh->state);
4724 }
4725
4726 pr_debug("locked=%d uptodate=%d to_read=%d"
4727 " to_write=%d failed=%d failed_num=%d,%d\n",
4728 s.locked, s.uptodate, s.to_read, s.to_write, s.failed,
4729 s.failed_num[0], s.failed_num[1]);
70d466f7
SL		 4730 /*
4731 * check if the array has lost more than max_degraded devices and,
474af965 4732 * if so, some requests might need to be failed.
70d466f7
SL		 4733 *
4734 * When journal device failed (log_failed), we will only process
4735 * the stripe if there is data need write to raid disks
474af965 4736 */
70d466f7
SL		 4737 if (s.failed > conf->max_degraded ||
4738 (s.log_failed && s.injournal == 0)) {
9a3f530f
N		 4739 sh->check_state = 0;
4740 sh->reconstruct_state = 0;
626f2092 4741 break_stripe_batch_list(sh, 0);
9a3f530f 4742 if (s.to_read+s.to_write+s.written)
bd83d0a2 4743 handle_failed_stripe(conf, sh, &s, disks);
9a3e1101 4744 if (s.syncing + s.replacing)
9a3f530f
N		 4745 handle_failed_sync(conf, sh, &s);
4746 }
474af965 4747
84789554
N		 4748 /* Now we check to see if any write operations have recently
4749 * completed
4750 */
4751 prexor = 0;
4752 if (sh->reconstruct_state == reconstruct_state_prexor_drain_result)
4753 prexor = 1;
4754 if (sh->reconstruct_state == reconstruct_state_drain_result ||
4755 sh->reconstruct_state == reconstruct_state_prexor_drain_result) {
4756 sh->reconstruct_state = reconstruct_state_idle;
4757
4758 /* All the 'written' buffers and the parity block are ready to
4759 * be written back to disk
4760 */
9e444768
SL		 4761 BUG_ON(!test_bit(R5_UPTODATE, &sh->dev[sh->pd_idx].flags) &&
4762 !test_bit(R5_Discard, &sh->dev[sh->pd_idx].flags));
84789554 4763 BUG_ON(sh->qd_idx >= 0 &&
9e444768
SL		 4764 !test_bit(R5_UPTODATE, &sh->dev[sh->qd_idx].flags) &&
4765 !test_bit(R5_Discard, &sh->dev[sh->qd_idx].flags));
84789554
N		 4766 for (i = disks; i--; ) {
4767 struct r5dev *dev = &sh->dev[i];
4768 if (test_bit(R5_LOCKED, &dev->flags) &&
4769 (i == sh->pd_idx || i == sh->qd_idx ||
1e6d690b
SL		 4770 dev->written || test_bit(R5_InJournal,
4771 &dev->flags))) {
84789554
N		 4772 pr_debug("Writing block %d\n", i);
4773 set_bit(R5_Wantwrite, &dev->flags);
4774 if (prexor)
4775 continue;
9c4bdf69
N		 4776 if (s.failed > 1)
4777 continue;
84789554
N		 4778 if (!test_bit(R5_Insync, &dev->flags) ||
4779 ((i == sh->pd_idx || i == sh->qd_idx) &&
4780 s.failed == 0))
4781 set_bit(STRIPE_INSYNC, &sh->state);
4782 }
4783 }
4784 if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE, &sh->state))
4785 s.dec_preread_active = 1;
4786 }
4787
ef5b7c69
N		 4788 /*
4789 * might be able to return some write requests if the parity blocks
4790 * are safe, or on a failed drive
4791 */
4792 pdev = &sh->dev[sh->pd_idx];
4793 s.p_failed = (s.failed >= 1 && s.failed_num[0] == sh->pd_idx)
4794 || (s.failed >= 2 && s.failed_num[1] == sh->pd_idx);
4795 qdev = &sh->dev[sh->qd_idx];
4796 s.q_failed = (s.failed >= 1 && s.failed_num[0] == sh->qd_idx)
4797 || (s.failed >= 2 && s.failed_num[1] == sh->qd_idx)
4798 || conf->level < 6;
4799
4800 if (s.written &&
4801 (s.p_failed || ((test_bit(R5_Insync, &pdev->flags)
4802 && !test_bit(R5_LOCKED, &pdev->flags)
4803 && (test_bit(R5_UPTODATE, &pdev->flags) ||
4804 test_bit(R5_Discard, &pdev->flags))))) &&
4805 (s.q_failed || ((test_bit(R5_Insync, &qdev->flags)
4806 && !test_bit(R5_LOCKED, &qdev->flags)
4807 && (test_bit(R5_UPTODATE, &qdev->flags) ||
4808 test_bit(R5_Discard, &qdev->flags))))))
bd83d0a2 4809 handle_stripe_clean_event(conf, sh, disks);
ef5b7c69 4810
1e6d690b 4811 if (s.just_cached)
bd83d0a2 4812 r5c_handle_cached_data_endio(conf, sh, disks);
ff875738 4813 log_stripe_write_finished(sh);
1e6d690b 4814
ef5b7c69
N		 4815 /* Now we might consider reading some blocks, either to check/generate
4816 * parity, or to satisfy requests
4817 * or to load a block that is being partially written.
4818 */
4819 if (s.to_read || s.non_overwrite
4820 || (conf->level == 6 && s.to_write && s.failed)
4821 || (s.syncing && (s.uptodate + s.compute < disks))
4822 || s.replacing
4823 || s.expanding)
4824 handle_stripe_fill(sh, &s, disks);
4825
2ded3703
SL		 4826 /*
4827 * When the stripe finishes full journal write cycle (write to journal
4828 * and raid disk), this is the clean up procedure so it is ready for
4829 * next operation.
4830 */
4831 r5c_finish_stripe_write_out(conf, sh, &s);
4832
4833 /*
4834 * Now to consider new write requests, cache write back and what else,
4835 * if anything should be read. We do not handle new writes when:
84789554
N		 4836 * 1/ A 'write' operation (copy+xor) is already in flight.
4837 * 2/ A 'check' operation is in flight, as it may clobber the parity
4838 * block.
2ded3703 4839 * 3/ A r5c cache log write is in flight.
84789554 4840 */
2ded3703
SL		 4841
4842 if (!sh->reconstruct_state && !sh->check_state && !sh->log_io) {
4843 if (!r5c_is_writeback(conf->log)) {
4844 if (s.to_write)
4845 handle_stripe_dirtying(conf, sh, &s, disks);
4846 } else { /* write back cache */
4847 int ret = 0;
4848
4849 /* First, try handle writes in caching phase */
4850 if (s.to_write)
4851 ret = r5c_try_caching_write(conf, sh, &s,
4852 disks);
4853 /*
4854 * If caching phase failed: ret == -EAGAIN
4855 * OR
4856 * stripe under reclaim: !caching && injournal
4857 *
4858 * fall back to handle_stripe_dirtying()
4859 */
4860 if (ret == -EAGAIN ||
4861 /* stripe under reclaim: !caching && injournal */
4862 (!test_bit(STRIPE_R5C_CACHING, &sh->state) &&
d7bd398e
SL		 4863 s.injournal > 0)) {
4864 ret = handle_stripe_dirtying(conf, sh, &s,
4865 disks);
4866 if (ret == -EAGAIN)
4867 goto finish;
4868 }
2ded3703
SL		 4869 }
4870 }
84789554
N		 4871
4872 /* maybe we need to check and possibly fix the parity for this stripe
4873 * Any reads will already have been scheduled, so we just see if enough
4874 * data is available. The parity check is held off while parity
4875 * dependent operations are in flight.
4876 */
4877 if (sh->check_state ||
4878 (s.syncing && s.locked == 0 &&
4879 !test_bit(STRIPE_COMPUTE_RUN, &sh->state) &&
4880 !test_bit(STRIPE_INSYNC, &sh->state))) {
4881 if (conf->level == 6)
4882 handle_parity_checks6(conf, sh, &s, disks);
4883 else
4884 handle_parity_checks5(conf, sh, &s, disks);
4885 }
c5a31000 4886
f94c0b66
N		 4887 if ((s.replacing || s.syncing) && s.locked == 0
4888 && !test_bit(STRIPE_COMPUTE_RUN, &sh->state)
4889 && !test_bit(STRIPE_REPLACED, &sh->state)) {
9a3e1101
N		 4890 /* Write out to replacement devices where possible */
4891 for (i = 0; i < conf->raid_disks; i++)
f94c0b66
N		 4892 if (test_bit(R5_NeedReplace, &sh->dev[i].flags)) {
4893 WARN_ON(!test_bit(R5_UPTODATE, &sh->dev[i].flags));
9a3e1101
N		 4894 set_bit(R5_WantReplace, &sh->dev[i].flags);
4895 set_bit(R5_LOCKED, &sh->dev[i].flags);
4896 s.locked++;
4897 }
f94c0b66
N		 4898 if (s.replacing)
4899 set_bit(STRIPE_INSYNC, &sh->state);
4900 set_bit(STRIPE_REPLACED, &sh->state);
9a3e1101
N		 4901 }
4902 if ((s.syncing || s.replacing) && s.locked == 0 &&
f94c0b66 4903 !test_bit(STRIPE_COMPUTE_RUN, &sh->state) &&
9a3e1101 4904 test_bit(STRIPE_INSYNC, &sh->state)) {
c5a31000
N		 4905 md_done_sync(conf->mddev, STRIPE_SECTORS, 1);
4906 clear_bit(STRIPE_SYNCING, &sh->state);
f8dfcffd
N		 4907 if (test_and_clear_bit(R5_Overlap, &sh->dev[sh->pd_idx].flags))
4908 wake_up(&conf->wait_for_overlap);
c5a31000
N		 4909 }
4910
4911 /* If the failed drives are just a ReadError, then we might need
4912 * to progress the repair/check process
4913 */
4914 if (s.failed <= conf->max_degraded && !conf->mddev->ro)
4915 for (i = 0; i < s.failed; i++) {
4916 struct r5dev *dev = &sh->dev[s.failed_num[i]];
4917 if (test_bit(R5_ReadError, &dev->flags)
4918 && !test_bit(R5_LOCKED, &dev->flags)
4919 && test_bit(R5_UPTODATE, &dev->flags)
4920 ) {
4921 if (!test_bit(R5_ReWrite, &dev->flags)) {
4922 set_bit(R5_Wantwrite, &dev->flags);
4923 set_bit(R5_ReWrite, &dev->flags);
4924 set_bit(R5_LOCKED, &dev->flags);
4925 s.locked++;
4926 } else {
4927 /* let's read it back */
4928 set_bit(R5_Wantread, &dev->flags);
4929 set_bit(R5_LOCKED, &dev->flags);
4930 s.locked++;
4931 }
4932 }
4933 }
4934
3687c061
N		 4935 /* Finish reconstruct operations initiated by the expansion process */
4936 if (sh->reconstruct_state == reconstruct_state_result) {
4937 struct stripe_head *sh_src
6d036f7d 4938 = raid5_get_active_stripe(conf, sh->sector, 1, 1, 1);
3687c061
N		 4939 if (sh_src && test_bit(STRIPE_EXPAND_SOURCE, &sh_src->state)) {
4940 /* sh cannot be written until sh_src has been read.
4941 * so arrange for sh to be delayed a little
4942 */
4943 set_bit(STRIPE_DELAYED, &sh->state);
4944 set_bit(STRIPE_HANDLE, &sh->state);
4945 if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE,
4946 &sh_src->state))
4947 atomic_inc(&conf->preread_active_stripes);
6d036f7d 4948 raid5_release_stripe(sh_src);
3687c061
N		 4949 goto finish;
4950 }
4951 if (sh_src)
6d036f7d 4952 raid5_release_stripe(sh_src);
3687c061
N		 4953
4954 sh->reconstruct_state = reconstruct_state_idle;
4955 clear_bit(STRIPE_EXPANDING, &sh->state);
4956 for (i = conf->raid_disks; i--; ) {
4957 set_bit(R5_Wantwrite, &sh->dev[i].flags);
4958 set_bit(R5_LOCKED, &sh->dev[i].flags);
4959 s.locked++;
4960 }
4961 }
f416885e 4962
3687c061
N		 4963 if (s.expanded && test_bit(STRIPE_EXPANDING, &sh->state) &&
4964 !sh->reconstruct_state) {
4965 /* Need to write out all blocks after computing parity */
4966 sh->disks = conf->raid_disks;
4967 stripe_set_idx(sh->sector, conf, 0, sh);
4968 schedule_reconstruction(sh, &s, 1, 1);
4969 } else if (s.expanded && !sh->reconstruct_state && s.locked == 0) {
4970 clear_bit(STRIPE_EXPAND_READY, &sh->state);
4971 atomic_dec(&conf->reshape_stripes);
4972 wake_up(&conf->wait_for_overlap);
4973 md_done_sync(conf->mddev, STRIPE_SECTORS, 1);
4974 }
4975
4976 if (s.expanding && s.locked == 0 &&
4977 !test_bit(STRIPE_COMPUTE_RUN, &sh->state))
4978 handle_stripe_expansion(conf, sh);
16a53ecc 4979
3687c061 4980finish:
6bfe0b49 4981 /* wait for this device to become unblocked */
5f066c63
N		 4982 if (unlikely(s.blocked_rdev)) {
4983 if (conf->mddev->external)
4984 md_wait_for_blocked_rdev(s.blocked_rdev,
4985 conf->mddev);
4986 else
4987 /* Internal metadata will immediately
4988 * be written by raid5d, so we don't
4989 * need to wait here.
4990 */
4991 rdev_dec_pending(s.blocked_rdev,
4992 conf->mddev);
4993 }
6bfe0b49 4994
bc2607f3
N		 4995 if (s.handle_bad_blocks)
4996 for (i = disks; i--; ) {
3cb03002 4997 struct md_rdev *rdev;
bc2607f3
N		 4998 struct r5dev *dev = &sh->dev[i];
4999 if (test_and_clear_bit(R5_WriteError, &dev->flags)) {
5000 /* We own a safe reference to the rdev */
5001 rdev = conf->disks[i].rdev;
5002 if (!rdev_set_badblocks(rdev, sh->sector,
5003 STRIPE_SECTORS, 0))
5004 md_error(conf->mddev, rdev);
5005 rdev_dec_pending(rdev, conf->mddev);
5006 }
b84db560
N		 5007 if (test_and_clear_bit(R5_MadeGood, &dev->flags)) {
5008 rdev = conf->disks[i].rdev;
5009 rdev_clear_badblocks(rdev, sh->sector,
c6563a8c 5010 STRIPE_SECTORS, 0);
b84db560
N		 5011 rdev_dec_pending(rdev, conf->mddev);
5012 }
977df362
N		 5013 if (test_and_clear_bit(R5_MadeGoodRepl, &dev->flags)) {
5014 rdev = conf->disks[i].replacement;
dd054fce
N		 5015 if (!rdev)
5016 /* rdev have been moved down */
5017 rdev = conf->disks[i].rdev;
977df362 5018 rdev_clear_badblocks(rdev, sh->sector,
c6563a8c 5019 STRIPE_SECTORS, 0);
977df362
N		 5020 rdev_dec_pending(rdev, conf->mddev);
5021 }
bc2607f3
N		 5022 }
5023
6c0069c0
YT		 5024 if (s.ops_request)
5025 raid_run_ops(sh, s.ops_request);
5026
f0e43bcd 5027 ops_run_io(sh, &s);
16a53ecc 5028
c5709ef6 5029 if (s.dec_preread_active) {
729a1866 5030 /* We delay this until after ops_run_io so that if make_request
e9c7469b 5031 * is waiting on a flush, it won't continue until the writes
729a1866
N		 5032 * have actually been submitted.
5033 */
5034 atomic_dec(&conf->preread_active_stripes);
5035 if (atomic_read(&conf->preread_active_stripes) <
5036 IO_THRESHOLD)
5037 md_wakeup_thread(conf->mddev->thread);
5038 }
5039
257a4b42 5040 clear_bit_unlock(STRIPE_ACTIVE, &sh->state);
16a53ecc
N		 5041}
5042
d1688a6d 5043static void raid5_activate_delayed(struct r5conf *conf)
16a53ecc
N		 5044{
5045 if (atomic_read(&conf->preread_active_stripes) < IO_THRESHOLD) {
5046 while (!list_empty(&conf->delayed_list)) {
5047 struct list_head *l = conf->delayed_list.next;
5048 struct stripe_head *sh;
5049 sh = list_entry(l, struct stripe_head, lru);
5050 list_del_init(l);
5051 clear_bit(STRIPE_DELAYED, &sh->state);
5052 if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE, &sh->state))
5053 atomic_inc(&conf->preread_active_stripes);
8b3e6cdc 5054 list_add_tail(&sh->lru, &conf->hold_list);
851c30c9 5055 raid5_wakeup_stripe_thread(sh);
16a53ecc 5056 }
482c0834 5057 }
16a53ecc
N		 5058}
5059
566c09c5
SL		 5060static void activate_bit_delay(struct r5conf *conf,
5061 struct list_head *temp_inactive_list)
16a53ecc
N		 5062{
5063 /* device_lock is held */
5064 struct list_head head;
5065 list_add(&head, &conf->bitmap_list);
5066 list_del_init(&conf->bitmap_list);
5067 while (!list_empty(&head)) {
5068 struct stripe_head *sh = list_entry(head.next, struct stripe_head, lru);
566c09c5 5069 int hash;
16a53ecc
N		 5070 list_del_init(&sh->lru);
5071 atomic_inc(&sh->count);
566c09c5
SL		 5072 hash = sh->hash_lock_index;
5073 __release_stripe(conf, sh, &temp_inactive_list[hash]);
16a53ecc
N		 5074 }
5075}
5076
5c675f83 5077static int raid5_congested(struct mddev *mddev, int bits)
f022b2fd 5078{
d1688a6d 5079 struct r5conf *conf = mddev->private;
f022b2fd
N		 5080
5081 /* No difference between reads and writes. Just check
5082 * how busy the stripe_cache is
5083 */
3fa841d7 5084
5423399a 5085 if (test_bit(R5_INACTIVE_BLOCKED, &conf->cache_state))
f022b2fd 5086 return 1;
a39f7afd
SL		 5087
5088 /* Also checks whether there is pressure on r5cache log space */
5089 if (test_bit(R5C_LOG_TIGHT, &conf->cache_state))
5090 return 1;
f022b2fd
N		 5091 if (conf->quiesce)
5092 return 1;
4bda556a 5093 if (atomic_read(&conf->empty_inactive_list_nr))
f022b2fd
N		 5094 return 1;
5095
5096 return 0;
5097}
5098
fd01b88c 5099static int in_chunk_boundary(struct mddev *mddev, struct bio *bio)
f679623f 5100{
3cb5edf4 5101 struct r5conf *conf = mddev->private;
10433d04 5102 sector_t sector = bio->bi_iter.bi_sector;
3cb5edf4 5103 unsigned int chunk_sectors;
aa8b57aa 5104 unsigned int bio_sectors = bio_sectors(bio);
f679623f 5105
10433d04
CH		 5106 WARN_ON_ONCE(bio->bi_partno);
5107
3cb5edf4 5108 chunk_sectors = min(conf->chunk_sectors, conf->prev_chunk_sectors);
f679623f
RBJ		 5109 return chunk_sectors >=
5110 ((sector & (chunk_sectors - 1)) + bio_sectors);
5111}
5112
46031f9a
RBJ		 5113/*
5114 * add bio to the retry LIFO ( in O(1) ... we are in interrupt )
5115 * later sampled by raid5d.
5116 */
d1688a6d 5117static void add_bio_to_retry(struct bio *bi,struct r5conf *conf)
46031f9a
RBJ		 5118{
5119 unsigned long flags;
5120
5121 spin_lock_irqsave(&conf->device_lock, flags);
5122
5123 bi->bi_next = conf->retry_read_aligned_list;
5124 conf->retry_read_aligned_list = bi;
5125
5126 spin_unlock_irqrestore(&conf->device_lock, flags);
5127 md_wakeup_thread(conf->mddev->thread);
5128}
5129
0472a42b
N		 5130static struct bio *remove_bio_from_retry(struct r5conf *conf,
5131 unsigned int *offset)
46031f9a
RBJ		 5132{
5133 struct bio *bi;
5134
5135 bi = conf->retry_read_aligned;
5136 if (bi) {
0472a42b 5137 *offset = conf->retry_read_offset;
46031f9a
RBJ		 5138 conf->retry_read_aligned = NULL;
5139 return bi;
5140 }
5141 bi = conf->retry_read_aligned_list;
5142 if(bi) {
387bb173 5143 conf->retry_read_aligned_list = bi->bi_next;
46031f9a 5144 bi->bi_next = NULL;
0472a42b 5145 *offset = 0;
46031f9a
RBJ		 5146 }
5147
5148 return bi;
5149}
5150
f679623f
RBJ		 5151/*
5152 * The "raid5_align_endio" should check if the read succeeded and if it
5153 * did, call bio_endio on the original bio (having bio_put the new bio
5154 * first).
5155 * If the read failed..
5156 */
4246a0b6 5157static void raid5_align_endio(struct bio *bi)
f679623f
RBJ		 5158{
5159 struct bio* raid_bi = bi->bi_private;
fd01b88c 5160 struct mddev *mddev;
d1688a6d 5161 struct r5conf *conf;
3cb03002 5162 struct md_rdev *rdev;
4e4cbee9 5163 blk_status_t error = bi->bi_status;
46031f9a 5164
f679623f 5165 bio_put(bi);
46031f9a 5166
46031f9a
RBJ		 5167 rdev = (void*)raid_bi->bi_next;
5168 raid_bi->bi_next = NULL;
2b7f2228
N		 5169 mddev = rdev->mddev;
5170 conf = mddev->private;
46031f9a
RBJ		 5171
5172 rdev_dec_pending(rdev, conf->mddev);
5173
9b81c842 5174 if (!error) {
4246a0b6 5175 bio_endio(raid_bi);
46031f9a 5176 if (atomic_dec_and_test(&conf->active_aligned_reads))
b1b46486 5177 wake_up(&conf->wait_for_quiescent);
6712ecf8 5178 return;
46031f9a
RBJ		 5179 }
5180
45b4233c 5181 pr_debug("raid5_align_endio : io error...handing IO for a retry\n");
46031f9a
RBJ		 5182
5183 add_bio_to_retry(raid_bi, conf);
f679623f
RBJ		 5184}
5185
7ef6b12a 5186static int raid5_read_one_chunk(struct mddev *mddev, struct bio *raid_bio)
f679623f 5187{
d1688a6d 5188 struct r5conf *conf = mddev->private;
8553fe7e 5189 int dd_idx;
f679623f 5190 struct bio* align_bi;
3cb03002 5191 struct md_rdev *rdev;
671488cc 5192 sector_t end_sector;
f679623f
RBJ		 5193
5194 if (!in_chunk_boundary(mddev, raid_bio)) {
7ef6b12a 5195 pr_debug("%s: non aligned\n", __func__);
f679623f
RBJ		 5196 return 0;
5197 }
5198 /*
d7a10308 5199 * use bio_clone_fast to make a copy of the bio
f679623f 5200 */
afeee514 5201 align_bi = bio_clone_fast(raid_bio, GFP_NOIO, &mddev->bio_set);
f679623f
RBJ		 5202 if (!align_bi)
5203 return 0;
5204 /*
5205 * set bi_end_io to a new function, and set bi_private to the
5206 * original bio.
5207 */
5208 align_bi->bi_end_io = raid5_align_endio;
5209 align_bi->bi_private = raid_bio;
5210 /*
5211 * compute position
5212 */
4f024f37
KO		 5213 align_bi->bi_iter.bi_sector =
5214 raid5_compute_sector(conf, raid_bio->bi_iter.bi_sector,
5215 0, &dd_idx, NULL);
f679623f 5216
f73a1c7d 5217 end_sector = bio_end_sector(align_bi);
f679623f 5218 rcu_read_lock();
671488cc
N		 5219 rdev = rcu_dereference(conf->disks[dd_idx].replacement);
5220 if (!rdev || test_bit(Faulty, &rdev->flags) ||
5221 rdev->recovery_offset < end_sector) {
5222 rdev = rcu_dereference(conf->disks[dd_idx].rdev);
5223 if (rdev &&
5224 (test_bit(Faulty, &rdev->flags) ||
5225 !(test_bit(In_sync, &rdev->flags) ||
5226 rdev->recovery_offset >= end_sector)))
5227 rdev = NULL;
5228 }
03b047f4
SL		 5229
5230 if (r5c_big_stripe_cached(conf, align_bi->bi_iter.bi_sector)) {
5231 rcu_read_unlock();
5232 bio_put(align_bi);
5233 return 0;
5234 }
5235
671488cc 5236 if (rdev) {
31c176ec
N		 5237 sector_t first_bad;
5238 int bad_sectors;
5239
f679623f
RBJ		 5240 atomic_inc(&rdev->nr_pending);
5241 rcu_read_unlock();
46031f9a 5242 raid_bio->bi_next = (void*)rdev;
74d46992 5243 bio_set_dev(align_bi, rdev->bdev);
b7c44ed9 5244 bio_clear_flag(align_bi, BIO_SEG_VALID);
46031f9a 5245
7140aafc 5246 if (is_badblock(rdev, align_bi->bi_iter.bi_sector,
4f024f37 5247 bio_sectors(align_bi),
31c176ec 5248 &first_bad, &bad_sectors)) {
387bb173
NB		 5249 bio_put(align_bi);
5250 rdev_dec_pending(rdev, mddev);
5251 return 0;
5252 }
5253
6c0544e2 5254 /* No reshape active, so we can trust rdev->data_offset */
4f024f37 5255 align_bi->bi_iter.bi_sector += rdev->data_offset;
6c0544e2 5256
46031f9a 5257 spin_lock_irq(&conf->device_lock);
b1b46486 5258 wait_event_lock_irq(conf->wait_for_quiescent,
46031f9a 5259 conf->quiesce == 0,
eed8c02e 5260 conf->device_lock);
46031f9a
RBJ		 5261 atomic_inc(&conf->active_aligned_reads);
5262 spin_unlock_irq(&conf->device_lock);
5263
e3620a3a 5264 if (mddev->gendisk)
74d46992 5265 trace_block_bio_remap(align_bi->bi_disk->queue,
e3620a3a 5266 align_bi, disk_devt(mddev->gendisk),
4f024f37 5267 raid_bio->bi_iter.bi_sector);
f679623f
RBJ		 5268 generic_make_request(align_bi);
5269 return 1;
5270 } else {
5271 rcu_read_unlock();
46031f9a 5272 bio_put(align_bi);
f679623f
RBJ		 5273 return 0;
5274 }
5275}
5276
7ef6b12a
ML		 5277static struct bio *chunk_aligned_read(struct mddev *mddev, struct bio *raid_bio)
5278{
5279 struct bio *split;
dd7a8f5d
N		 5280 sector_t sector = raid_bio->bi_iter.bi_sector;
5281 unsigned chunk_sects = mddev->chunk_sectors;
5282 unsigned sectors = chunk_sects - (sector & (chunk_sects-1));
7ef6b12a 5283
dd7a8f5d
N		 5284 if (sectors < bio_sectors(raid_bio)) {
5285 struct r5conf *conf = mddev->private;
afeee514 5286 split = bio_split(raid_bio, sectors, GFP_NOIO, &conf->bio_split);
dd7a8f5d
N		 5287 bio_chain(split, raid_bio);
5288 generic_make_request(raid_bio);
5289 raid_bio = split;
5290 }
7ef6b12a 5291
dd7a8f5d
N		 5292 if (!raid5_read_one_chunk(mddev, raid_bio))
5293 return raid_bio;
7ef6b12a
ML		 5294
5295 return NULL;
5296}
5297
8b3e6cdc
DW		 5298/* __get_priority_stripe - get the next stripe to process
5299 *
5300 * Full stripe writes are allowed to pass preread active stripes up until
5301 * the bypass_threshold is exceeded. In general the bypass_count
5302 * increments when the handle_list is handled before the hold_list; however, it
5303 * will not be incremented when STRIPE_IO_STARTED is sampled set signifying a
5304 * stripe with in flight i/o. The bypass_count will be reset when the
5305 * head of the hold_list has changed, i.e. the head was promoted to the
5306 * handle_list.
5307 */
851c30c9 5308static struct stripe_head *__get_priority_stripe(struct r5conf *conf, int group)
8b3e6cdc 5309{
535ae4eb 5310 struct stripe_head *sh, *tmp;
851c30c9 5311 struct list_head *handle_list = NULL;
535ae4eb 5312 struct r5worker_group *wg;
70d466f7
SL		 5313 bool second_try = !r5c_is_writeback(conf->log) &&
5314 !r5l_log_disk_error(conf);
5315 bool try_loprio = test_bit(R5C_LOG_TIGHT, &conf->cache_state) ||
5316 r5l_log_disk_error(conf);
851c30c9 5317
535ae4eb
SL		 5318again:
5319 wg = NULL;
5320 sh = NULL;
851c30c9 5321 if (conf->worker_cnt_per_group == 0) {
535ae4eb
SL		 5322 handle_list = try_loprio ? &conf->loprio_list :
5323 &conf->handle_list;
851c30c9 5324 } else if (group != ANY_GROUP) {
535ae4eb
SL		 5325 handle_list = try_loprio ? &conf->worker_groups[group].loprio_list :
5326 &conf->worker_groups[group].handle_list;
bfc90cb0 5327 wg = &conf->worker_groups[group];
851c30c9
SL		 5328 } else {
5329 int i;
5330 for (i = 0; i < conf->group_cnt; i++) {
535ae4eb
SL		 5331 handle_list = try_loprio ? &conf->worker_groups[i].loprio_list :
5332 &conf->worker_groups[i].handle_list;
bfc90cb0 5333 wg = &conf->worker_groups[i];
851c30c9
SL		 5334 if (!list_empty(handle_list))
5335 break;
5336 }
5337 }
8b3e6cdc
DW		 5338
5339 pr_debug("%s: handle: %s hold: %s full_writes: %d bypass_count: %d\n",
5340 __func__,
851c30c9 5341 list_empty(handle_list) ? "empty" : "busy",
8b3e6cdc
DW		 5342 list_empty(&conf->hold_list) ? "empty" : "busy",
5343 atomic_read(&conf->pending_full_writes), conf->bypass_count);
5344
851c30c9
SL		 5345 if (!list_empty(handle_list)) {
5346 sh = list_entry(handle_list->next, typeof(*sh), lru);
8b3e6cdc
DW		 5347
5348 if (list_empty(&conf->hold_list))
5349 conf->bypass_count = 0;
5350 else if (!test_bit(STRIPE_IO_STARTED, &sh->state)) {
5351 if (conf->hold_list.next == conf->last_hold)
5352 conf->bypass_count++;
5353 else {
5354 conf->last_hold = conf->hold_list.next;
5355 conf->bypass_count -= conf->bypass_threshold;
5356 if (conf->bypass_count < 0)
5357 conf->bypass_count = 0;
5358 }
5359 }
5360 } else if (!list_empty(&conf->hold_list) &&
5361 ((conf->bypass_threshold &&
5362 conf->bypass_count > conf->bypass_threshold) ||
5363 atomic_read(&conf->pending_full_writes) == 0)) {
851c30c9
SL		 5364
5365 list_for_each_entry(tmp, &conf->hold_list, lru) {
5366 if (conf->worker_cnt_per_group == 0 ||
5367 group == ANY_GROUP ||
5368 !cpu_online(tmp->cpu) ||
5369 cpu_to_group(tmp->cpu) == group) {
5370 sh = tmp;
5371 break;
5372 }
5373 }
5374
5375 if (sh) {
5376 conf->bypass_count -= conf->bypass_threshold;
5377 if (conf->bypass_count < 0)
5378 conf->bypass_count = 0;
5379 }
bfc90cb0 5380 wg = NULL;
851c30c9
SL		 5381 }
5382
535ae4eb
SL		 5383 if (!sh) {
5384 if (second_try)
5385 return NULL;
5386 second_try = true;
5387 try_loprio = !try_loprio;
5388 goto again;
5389 }
8b3e6cdc 5390
bfc90cb0
SL		 5391 if (wg) {
5392 wg->stripes_cnt--;
5393 sh->group = NULL;
5394 }
8b3e6cdc 5395 list_del_init(&sh->lru);
c7a6d35e 5396 BUG_ON(atomic_inc_return(&sh->count) != 1);
8b3e6cdc
DW		 5397 return sh;
5398}
f679623f 5399
8811b596
SL		 5400struct raid5_plug_cb {
5401 struct blk_plug_cb cb;
5402 struct list_head list;
566c09c5 5403 struct list_head temp_inactive_list[NR_STRIPE_HASH_LOCKS];
8811b596
SL		 5404};
5405
5406static void raid5_unplug(struct blk_plug_cb *blk_cb, bool from_schedule)
5407{
5408 struct raid5_plug_cb *cb = container_of(
5409 blk_cb, struct raid5_plug_cb, cb);
5410 struct stripe_head *sh;
5411 struct mddev *mddev = cb->cb.data;
5412 struct r5conf *conf = mddev->private;
a9add5d9 5413 int cnt = 0;
566c09c5 5414 int hash;
8811b596
SL		 5415
5416 if (cb->list.next && !list_empty(&cb->list)) {
5417 spin_lock_irq(&conf->device_lock);
5418 while (!list_empty(&cb->list)) {
5419 sh = list_first_entry(&cb->list, struct stripe_head, lru);
5420 list_del_init(&sh->lru);
5421 /*
5422 * avoid race release_stripe_plug() sees
5423 * STRIPE_ON_UNPLUG_LIST clear but the stripe
5424 * is still in our list
5425 */
4e857c58 5426 smp_mb__before_atomic();
8811b596 5427 clear_bit(STRIPE_ON_UNPLUG_LIST, &sh->state);
773ca82f
SL		 5428 /*
5429 * STRIPE_ON_RELEASE_LIST could be set here. In that
5430 * case, the count is always > 1 here
5431 */
566c09c5
SL		 5432 hash = sh->hash_lock_index;
5433 __release_stripe(conf, sh, &cb->temp_inactive_list[hash]);
a9add5d9 5434 cnt++;
8811b596
SL		 5435 }
5436 spin_unlock_irq(&conf->device_lock);
5437 }
566c09c5
SL		 5438 release_inactive_stripe_list(conf, cb->temp_inactive_list,
5439 NR_STRIPE_HASH_LOCKS);
e3620a3a
JB		 5440 if (mddev->queue)
5441 trace_block_unplug(mddev->queue, cnt, !from_schedule);
8811b596
SL		 5442 kfree(cb);
5443}
5444
5445static void release_stripe_plug(struct mddev *mddev,
5446 struct stripe_head *sh)
5447{
5448 struct blk_plug_cb *blk_cb = blk_check_plugged(
5449 raid5_unplug, mddev,
5450 sizeof(struct raid5_plug_cb));
5451 struct raid5_plug_cb *cb;
5452
5453 if (!blk_cb) {
6d036f7d 5454 raid5_release_stripe(sh);
8811b596
SL		 5455 return;
5456 }
5457
5458 cb = container_of(blk_cb, struct raid5_plug_cb, cb);
5459
566c09c5
SL		 5460 if (cb->list.next == NULL) {
5461 int i;
8811b596 5462 INIT_LIST_HEAD(&cb->list);
566c09c5
SL		 5463 for (i = 0; i < NR_STRIPE_HASH_LOCKS; i++)
5464 INIT_LIST_HEAD(cb->temp_inactive_list + i);
5465 }
8811b596
SL		 5466
5467 if (!test_and_set_bit(STRIPE_ON_UNPLUG_LIST, &sh->state))
5468 list_add_tail(&sh->lru, &cb->list);
5469 else
6d036f7d 5470 raid5_release_stripe(sh);
8811b596
SL		 5471}
5472
620125f2
SL		 5473static void make_discard_request(struct mddev *mddev, struct bio *bi)
5474{
5475 struct r5conf *conf = mddev->private;
5476 sector_t logical_sector, last_sector;
5477 struct stripe_head *sh;
620125f2
SL		 5478 int stripe_sectors;
5479
5480 if (mddev->reshape_position != MaxSector)
5481 /* Skip discard while reshape is happening */
5482 return;
5483
4f024f37
KO		 5484 logical_sector = bi->bi_iter.bi_sector & ~((sector_t)STRIPE_SECTORS-1);
5485 last_sector = bi->bi_iter.bi_sector + (bi->bi_iter.bi_size>>9);
620125f2
SL		 5486
5487 bi->bi_next = NULL;
620125f2
SL		 5488
5489 stripe_sectors = conf->chunk_sectors *
5490 (conf->raid_disks - conf->max_degraded);
5491 logical_sector = DIV_ROUND_UP_SECTOR_T(logical_sector,
5492 stripe_sectors);
5493 sector_div(last_sector, stripe_sectors);
5494
5495 logical_sector *= conf->chunk_sectors;
5496 last_sector *= conf->chunk_sectors;
5497
5498 for (; logical_sector < last_sector;
5499 logical_sector += STRIPE_SECTORS) {
5500 DEFINE_WAIT(w);
5501 int d;
5502 again:
6d036f7d 5503 sh = raid5_get_active_stripe(conf, logical_sector, 0, 0, 0);
620125f2
SL		 5504 prepare_to_wait(&conf->wait_for_overlap, &w,
5505 TASK_UNINTERRUPTIBLE);
f8dfcffd
N		 5506 set_bit(R5_Overlap, &sh->dev[sh->pd_idx].flags);
5507 if (test_bit(STRIPE_SYNCING, &sh->state)) {
6d036f7d 5508 raid5_release_stripe(sh);
f8dfcffd
N		 5509 schedule();
5510 goto again;
5511 }
5512 clear_bit(R5_Overlap, &sh->dev[sh->pd_idx].flags);
620125f2
SL		 5513 spin_lock_irq(&sh->stripe_lock);
5514 for (d = 0; d < conf->raid_disks; d++) {
5515 if (d == sh->pd_idx || d == sh->qd_idx)
5516 continue;
5517 if (sh->dev[d].towrite || sh->dev[d].toread) {
5518 set_bit(R5_Overlap, &sh->dev[d].flags);
5519 spin_unlock_irq(&sh->stripe_lock);
6d036f7d 5520 raid5_release_stripe(sh);
620125f2
SL		 5521 schedule();
5522 goto again;
5523 }
5524 }
f8dfcffd 5525 set_bit(STRIPE_DISCARD, &sh->state);
620125f2 5526 finish_wait(&conf->wait_for_overlap, &w);
7a87f434 5527 sh->overwrite_disks = 0;
620125f2
SL		 5528 for (d = 0; d < conf->raid_disks; d++) {
5529 if (d == sh->pd_idx || d == sh->qd_idx)
5530 continue;
5531 sh->dev[d].towrite = bi;
5532 set_bit(R5_OVERWRITE, &sh->dev[d].flags);
016c76ac 5533 bio_inc_remaining(bi);
49728050 5534 md_write_inc(mddev, bi);
7a87f434 5535 sh->overwrite_disks++;
620125f2
SL		 5536 }
5537 spin_unlock_irq(&sh->stripe_lock);
5538 if (conf->mddev->bitmap) {
5539 for (d = 0;
5540 d < conf->raid_disks - conf->max_degraded;
5541 d++)
5542 bitmap_startwrite(mddev->bitmap,
5543 sh->sector,
5544 STRIPE_SECTORS,
5545 0);
5546 sh->bm_seq = conf->seq_flush + 1;
5547 set_bit(STRIPE_BIT_DELAY, &sh->state);
5548 }
5549
5550 set_bit(STRIPE_HANDLE, &sh->state);
5551 clear_bit(STRIPE_DELAYED, &sh->state);
5552 if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE, &sh->state))
5553 atomic_inc(&conf->preread_active_stripes);
5554 release_stripe_plug(mddev, sh);
5555 }
5556
016c76ac 5557 bio_endio(bi);
620125f2
SL		 5558}
5559
cc27b0c7 5560static bool raid5_make_request(struct mddev *mddev, struct bio * bi)
1da177e4 5561{
d1688a6d 5562 struct r5conf *conf = mddev->private;
911d4ee8 5563 int dd_idx;
1da177e4
LT		 5564 sector_t new_sector;
5565 sector_t logical_sector, last_sector;
5566 struct stripe_head *sh;
a362357b 5567 const int rw = bio_data_dir(bi);
27c0f68f
SL		 5568 DEFINE_WAIT(w);
5569 bool do_prepare;
3bddb7f8 5570 bool do_flush = false;
1da177e4 5571
1eff9d32 5572 if (unlikely(bi->bi_opf & REQ_PREFLUSH)) {
1532d9e8 5573 int ret = log_handle_flush_request(conf, bi);
828cbe98
SL		 5574
5575 if (ret == 0)
cc27b0c7 5576 return true;
828cbe98
SL		 5577 if (ret == -ENODEV) {
5578 md_flush_request(mddev, bi);
cc27b0c7 5579 return true;
828cbe98
SL		 5580 }
5581 /* ret == -EAGAIN, fallback */
3bddb7f8
SL		 5582 /*
5583 * if r5l_handle_flush_request() didn't clear REQ_PREFLUSH,
5584 * we need to flush journal device
5585 */
5586 do_flush = bi->bi_opf & REQ_PREFLUSH;
e5dcdd80
N		 5587 }
5588
cc27b0c7
N		 5589 if (!md_write_start(mddev, bi))
5590 return false;
9ffc8f7c
EM		 5591 /*
5592 * If array is degraded, better not do chunk aligned read because
5593 * later we might have to read it again in order to reconstruct
5594 * data on failed drives.
5595 */
5596 if (rw == READ && mddev->degraded == 0 &&
7ef6b12a
ML		 5597 mddev->reshape_position == MaxSector) {
5598 bi = chunk_aligned_read(mddev, bi);
5599 if (!bi)
cc27b0c7 5600 return true;
7ef6b12a 5601 }
52488615 5602
796a5cf0 5603 if (unlikely(bio_op(bi) == REQ_OP_DISCARD)) {
620125f2 5604 make_discard_request(mddev, bi);
cc27b0c7
N		 5605 md_write_end(mddev);
5606 return true;
620125f2
SL		 5607 }
5608
4f024f37 5609 logical_sector = bi->bi_iter.bi_sector & ~((sector_t)STRIPE_SECTORS-1);
f73a1c7d 5610 last_sector = bio_end_sector(bi);
1da177e4 5611 bi->bi_next = NULL;
06d91a5f 5612
27c0f68f 5613 prepare_to_wait(&conf->wait_for_overlap, &w, TASK_UNINTERRUPTIBLE);
1da177e4 5614 for (;logical_sector < last_sector; logical_sector += STRIPE_SECTORS) {
b5663ba4 5615 int previous;
c46501b2 5616 int seq;
b578d55f 5617
27c0f68f 5618 do_prepare = false;
7ecaa1e6 5619 retry:
c46501b2 5620 seq = read_seqcount_begin(&conf->gen_lock);
b5663ba4 5621 previous = 0;
27c0f68f
SL		 5622 if (do_prepare)
5623 prepare_to_wait(&conf->wait_for_overlap, &w,
5624 TASK_UNINTERRUPTIBLE);
b0f9ec04 5625 if (unlikely(conf->reshape_progress != MaxSector)) {
fef9c61f 5626 /* spinlock is needed as reshape_progress may be
df8e7f76
N		 5627 * 64bit on a 32bit platform, and so it might be
5628 * possible to see a half-updated value
aeb878b0 5629 * Of course reshape_progress could change after
df8e7f76
N		 5630 * the lock is dropped, so once we get a reference
5631 * to the stripe that we think it is, we will have
5632 * to check again.
5633 */
7ecaa1e6 5634 spin_lock_irq(&conf->device_lock);
2c810cdd 5635 if (mddev->reshape_backwards
fef9c61f
N		 5636 ? logical_sector < conf->reshape_progress
5637 : logical_sector >= conf->reshape_progress) {
b5663ba4
N		 5638 previous = 1;
5639 } else {
2c810cdd 5640 if (mddev->reshape_backwards
fef9c61f
N		 5641 ? logical_sector < conf->reshape_safe
5642 : logical_sector >= conf->reshape_safe) {
b578d55f
N		 5643 spin_unlock_irq(&conf->device_lock);
5644 schedule();
27c0f68f 5645 do_prepare = true;
b578d55f
N		 5646 goto retry;
5647 }
5648 }
7ecaa1e6
N		 5649 spin_unlock_irq(&conf->device_lock);
5650 }
16a53ecc 5651
112bf897
N		 5652 new_sector = raid5_compute_sector(conf, logical_sector,
5653 previous,
911d4ee8 5654 &dd_idx, NULL);
849674e4 5655 pr_debug("raid456: raid5_make_request, sector %llu logical %llu\n",
c46501b2 5656 (unsigned long long)new_sector,
1da177e4
LT		 5657 (unsigned long long)logical_sector);
5658
6d036f7d 5659 sh = raid5_get_active_stripe(conf, new_sector, previous,
1eff9d32 5660 (bi->bi_opf & REQ_RAHEAD), 0);
1da177e4 5661 if (sh) {
b0f9ec04 5662 if (unlikely(previous)) {
7ecaa1e6 5663 /* expansion might have moved on while waiting for a
df8e7f76
N		 5664 * stripe, so we must do the range check again.
5665 * Expansion could still move past after this
5666 * test, but as we are holding a reference to
5667 * 'sh', we know that if that happens,
5668 * STRIPE_EXPANDING will get set and the expansion
5669 * won't proceed until we finish with the stripe.
7ecaa1e6
N		 5670 */
5671 int must_retry = 0;
5672 spin_lock_irq(&conf->device_lock);
2c810cdd 5673 if (mddev->reshape_backwards
b0f9ec04
N		 5674 ? logical_sector >= conf->reshape_progress
5675 : logical_sector < conf->reshape_progress)
7ecaa1e6
N		 5676 /* mismatch, need to try again */
5677 must_retry = 1;
5678 spin_unlock_irq(&conf->device_lock);
5679 if (must_retry) {
6d036f7d 5680 raid5_release_stripe(sh);
7a3ab908 5681 schedule();
27c0f68f 5682 do_prepare = true;
7ecaa1e6
N		 5683 goto retry;
5684 }
5685 }
c46501b2
N		 5686 if (read_seqcount_retry(&conf->gen_lock, seq)) {
5687 /* Might have got the wrong stripe_head
5688 * by accident
5689 */
6d036f7d 5690 raid5_release_stripe(sh);
c46501b2
N		 5691 goto retry;
5692 }
e62e58a5 5693
7ecaa1e6 5694 if (test_bit(STRIPE_EXPANDING, &sh->state) ||
da41ba65 5695 !add_stripe_bio(sh, bi, dd_idx, rw, previous)) {
7ecaa1e6
N		 5696 /* Stripe is busy expanding or
5697 * add failed due to overlap. Flush everything
1da177e4
LT		 5698 * and wait a while
5699 */
482c0834 5700 md_wakeup_thread(mddev->thread);
6d036f7d 5701 raid5_release_stripe(sh);
1da177e4 5702 schedule();
27c0f68f 5703 do_prepare = true;
1da177e4
LT		 5704 goto retry;
5705 }
3bddb7f8
SL		 5706 if (do_flush) {
5707 set_bit(STRIPE_R5C_PREFLUSH, &sh->state);
5708 /* we only need flush for one stripe */
5709 do_flush = false;
5710 }
5711
6ed3003c
N		 5712 set_bit(STRIPE_HANDLE, &sh->state);
5713 clear_bit(STRIPE_DELAYED, &sh->state);
59fc630b 5714 if ((!sh->batch_head || sh == sh->batch_head) &&
1eff9d32 5715 (bi->bi_opf & REQ_SYNC) &&
729a1866
N		 5716 !test_and_set_bit(STRIPE_PREREAD_ACTIVE, &sh->state))
5717 atomic_inc(&conf->preread_active_stripes);
8811b596 5718 release_stripe_plug(mddev, sh);
1da177e4
LT		 5719 } else {
5720 /* cannot get stripe for read-ahead, just give-up */
4e4cbee9 5721 bi->bi_status = BLK_STS_IOERR;
1da177e4
LT		 5722 break;
5723 }
1da177e4 5724 }
27c0f68f 5725 finish_wait(&conf->wait_for_overlap, &w);
7c13edc8 5726
49728050
N		 5727 if (rw == WRITE)
5728 md_write_end(mddev);
016c76ac 5729 bio_endio(bi);
cc27b0c7 5730 return true;
1da177e4
LT		 5731}
5732
fd01b88c 5733static sector_t raid5_size(struct mddev *mddev, sector_t sectors, int raid_disks);
b522adcd 5734
fd01b88c 5735static sector_t reshape_request(struct mddev *mddev, sector_t sector_nr, int *skipped)
1da177e4 5736{
52c03291
N		 5737 /* reshaping is quite different to recovery/resync so it is
5738 * handled quite separately ... here.
5739 *
5740 * On each call to sync_request, we gather one chunk worth of
5741 * destination stripes and flag them as expanding.
5742 * Then we find all the source stripes and request reads.
5743 * As the reads complete, handle_stripe will copy the data
5744 * into the destination stripe and release that stripe.
5745 */
d1688a6d 5746 struct r5conf *conf = mddev->private;
1da177e4 5747 struct stripe_head *sh;
db0505d3 5748 struct md_rdev *rdev;
ccfcc3c1 5749 sector_t first_sector, last_sector;
f416885e
N		 5750 int raid_disks = conf->previous_raid_disks;
5751 int data_disks = raid_disks - conf->max_degraded;
5752 int new_data_disks = conf->raid_disks - conf->max_degraded;
52c03291
N		 5753 int i;
5754 int dd_idx;
c8f517c4 5755 sector_t writepos, readpos, safepos;
ec32a2bd 5756 sector_t stripe_addr;
7a661381 5757 int reshape_sectors;
ab69ae12 5758 struct list_head stripes;
92140480 5759 sector_t retn;
52c03291 5760
fef9c61f
N		 5761 if (sector_nr == 0) {
5762 /* If restarting in the middle, skip the initial sectors */
2c810cdd 5763 if (mddev->reshape_backwards &&
fef9c61f
N		 5764 conf->reshape_progress < raid5_size(mddev, 0, 0)) {
5765 sector_nr = raid5_size(mddev, 0, 0)
5766 - conf->reshape_progress;
6cbd8148
N		 5767 } else if (mddev->reshape_backwards &&
5768 conf->reshape_progress == MaxSector) {
5769 /* shouldn't happen, but just in case, finish up.*/
5770 sector_nr = MaxSector;
2c810cdd 5771 } else if (!mddev->reshape_backwards &&
fef9c61f
N		 5772 conf->reshape_progress > 0)
5773 sector_nr = conf->reshape_progress;
f416885e 5774 sector_div(sector_nr, new_data_disks);
fef9c61f 5775 if (sector_nr) {
8dee7211
N		 5776 mddev->curr_resync_completed = sector_nr;
5777 sysfs_notify(&mddev->kobj, NULL, "sync_completed");
fef9c61f 5778 *skipped = 1;
92140480
N		 5779 retn = sector_nr;
5780 goto finish;
fef9c61f 5781 }
52c03291
N		 5782 }
5783
7a661381
N		 5784 /* We need to process a full chunk at a time.
5785 * If old and new chunk sizes differ, we need to process the
5786 * largest of these
5787 */
3cb5edf4
N		 5788
5789 reshape_sectors = max(conf->chunk_sectors, conf->prev_chunk_sectors);
7a661381 5790
b5254dd5
N		 5791 /* We update the metadata at least every 10 seconds, or when
5792 * the data about to be copied would over-write the source of
5793 * the data at the front of the range. i.e. one new_stripe
5794 * along from reshape_progress new_maps to after where
5795 * reshape_safe old_maps to
52c03291 5796 */
fef9c61f 5797 writepos = conf->reshape_progress;
f416885e 5798 sector_div(writepos, new_data_disks);
c8f517c4
N		 5799 readpos = conf->reshape_progress;
5800 sector_div(readpos, data_disks);
fef9c61f 5801 safepos = conf->reshape_safe;
f416885e 5802 sector_div(safepos, data_disks);
2c810cdd 5803 if (mddev->reshape_backwards) {
c74c0d76
N		 5804 BUG_ON(writepos < reshape_sectors);
5805 writepos -= reshape_sectors;
c8f517c4 5806 readpos += reshape_sectors;
7a661381 5807 safepos += reshape_sectors;
fef9c61f 5808 } else {
7a661381 5809 writepos += reshape_sectors;
c74c0d76
N		 5810 /* readpos and safepos are worst-case calculations.
5811 * A negative number is overly pessimistic, and causes
5812 * obvious problems for unsigned storage. So clip to 0.
5813 */
ed37d83e
N		 5814 readpos -= min_t(sector_t, reshape_sectors, readpos);
5815 safepos -= min_t(sector_t, reshape_sectors, safepos);
fef9c61f 5816 }
52c03291 5817
b5254dd5
N		 5818 /* Having calculated the 'writepos' possibly use it
5819 * to set 'stripe_addr' which is where we will write to.
5820 */
5821 if (mddev->reshape_backwards) {
5822 BUG_ON(conf->reshape_progress == 0);
5823 stripe_addr = writepos;
5824 BUG_ON((mddev->dev_sectors &
5825 ~((sector_t)reshape_sectors - 1))
5826 - reshape_sectors - stripe_addr
5827 != sector_nr);
5828 } else {
5829 BUG_ON(writepos != sector_nr + reshape_sectors);
5830 stripe_addr = sector_nr;
5831 }
5832
c8f517c4
N		 5833 /* 'writepos' is the most advanced device address we might write.
5834 * 'readpos' is the least advanced device address we might read.
5835 * 'safepos' is the least address recorded in the metadata as having
5836 * been reshaped.
b5254dd5
N		 5837 * If there is a min_offset_diff, these are adjusted either by
5838 * increasing the safepos/readpos if diff is negative, or
5839 * increasing writepos if diff is positive.
5840 * If 'readpos' is then behind 'writepos', there is no way that we can
c8f517c4
N		 5841 * ensure safety in the face of a crash - that must be done by userspace
5842 * making a backup of the data. So in that case there is no particular
5843 * rush to update metadata.
5844 * Otherwise if 'safepos' is behind 'writepos', then we really need to
5845 * update the metadata to advance 'safepos' to match 'readpos' so that
5846 * we can be safe in the event of a crash.
5847 * So we insist on updating metadata if safepos is behind writepos and
5848 * readpos is beyond writepos.
5849 * In any case, update the metadata every 10 seconds.
5850 * Maybe that number should be configurable, but I'm not sure it is
5851 * worth it.... maybe it could be a multiple of safemode_delay???
5852 */
b5254dd5
N		 5853 if (conf->min_offset_diff < 0) {
5854 safepos += -conf->min_offset_diff;
5855 readpos += -conf->min_offset_diff;
5856 } else
5857 writepos += conf->min_offset_diff;
5858
2c810cdd 5859 if ((mddev->reshape_backwards
c8f517c4
N		 5860 ? (safepos > writepos && readpos < writepos)
5861 : (safepos < writepos && readpos > writepos)) ||
5862 time_after(jiffies, conf->reshape_checkpoint + 10*HZ)) {
52c03291
N		 5863 /* Cannot proceed until we've updated the superblock... */
5864 wait_event(conf->wait_for_overlap,
c91abf5a
N		 5865 atomic_read(&conf->reshape_stripes)==0
5866 || test_bit(MD_RECOVERY_INTR, &mddev->recovery));
5867 if (atomic_read(&conf->reshape_stripes) != 0)
5868 return 0;
fef9c61f 5869 mddev->reshape_position = conf->reshape_progress;
75d3da43 5870 mddev->curr_resync_completed = sector_nr;
db0505d3
N		 5871 if (!mddev->reshape_backwards)
5872 /* Can update recovery_offset */
5873 rdev_for_each(rdev, mddev)
5874 if (rdev->raid_disk >= 0 &&
5875 !test_bit(Journal, &rdev->flags) &&
5876 !test_bit(In_sync, &rdev->flags) &&
5877 rdev->recovery_offset < sector_nr)
5878 rdev->recovery_offset = sector_nr;
5879
c8f517c4 5880 conf->reshape_checkpoint = jiffies;
2953079c 5881 set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
52c03291 5882 md_wakeup_thread(mddev->thread);
2953079c 5883 wait_event(mddev->sb_wait, mddev->sb_flags == 0 ||
c91abf5a
N		 5884 test_bit(MD_RECOVERY_INTR, &mddev->recovery));
5885 if (test_bit(MD_RECOVERY_INTR, &mddev->recovery))
5886 return 0;
52c03291 5887 spin_lock_irq(&conf->device_lock);
fef9c61f 5888 conf->reshape_safe = mddev->reshape_position;
52c03291
N		 5889 spin_unlock_irq(&conf->device_lock);
5890 wake_up(&conf->wait_for_overlap);
acb180b0 5891 sysfs_notify(&mddev->kobj, NULL, "sync_completed");
52c03291
N		 5892 }
5893
ab69ae12 5894 INIT_LIST_HEAD(&stripes);
7a661381 5895 for (i = 0; i < reshape_sectors; i += STRIPE_SECTORS) {
52c03291 5896 int j;
a9f326eb 5897 int skipped_disk = 0;
6d036f7d 5898 sh = raid5_get_active_stripe(conf, stripe_addr+i, 0, 0, 1);
52c03291
N		 5899 set_bit(STRIPE_EXPANDING, &sh->state);
5900 atomic_inc(&conf->reshape_stripes);
5901 /* If any of this stripe is beyond the end of the old
5902 * array, then we need to zero those blocks
5903 */
5904 for (j=sh->disks; j--;) {
5905 sector_t s;
5906 if (j == sh->pd_idx)
5907 continue;
f416885e 5908 if (conf->level == 6 &&
d0dabf7e 5909 j == sh->qd_idx)
f416885e 5910 continue;
6d036f7d 5911 s = raid5_compute_blocknr(sh, j, 0);
b522adcd 5912 if (s < raid5_size(mddev, 0, 0)) {
a9f326eb 5913 skipped_disk = 1;
52c03291
N		 5914 continue;
5915 }
5916 memset(page_address(sh->dev[j].page), 0, STRIPE_SIZE);
5917 set_bit(R5_Expanded, &sh->dev[j].flags);
5918 set_bit(R5_UPTODATE, &sh->dev[j].flags);
5919 }
a9f326eb 5920 if (!skipped_disk) {
52c03291
N		 5921 set_bit(STRIPE_EXPAND_READY, &sh->state);
5922 set_bit(STRIPE_HANDLE, &sh->state);
5923 }
ab69ae12 5924 list_add(&sh->lru, &stripes);
52c03291
N		 5925 }
5926 spin_lock_irq(&conf->device_lock);
2c810cdd 5927 if (mddev->reshape_backwards)
7a661381 5928 conf->reshape_progress -= reshape_sectors * new_data_disks;
fef9c61f 5929 else
7a661381 5930 conf->reshape_progress += reshape_sectors * new_data_disks;
52c03291
N		 5931 spin_unlock_irq(&conf->device_lock);
5932 /* Ok, those stripe are ready. We can start scheduling
5933 * reads on the source stripes.
5934 * The source stripes are determined by mapping the first and last
5935 * block on the destination stripes.
5936 */
52c03291 5937 first_sector =
ec32a2bd 5938 raid5_compute_sector(conf, stripe_addr*(new_data_disks),
911d4ee8 5939 1, &dd_idx, NULL);
52c03291 5940 last_sector =
0e6e0271 5941 raid5_compute_sector(conf, ((stripe_addr+reshape_sectors)
09c9e5fa 5942 * new_data_disks - 1),
911d4ee8 5943 1, &dd_idx, NULL);
58c0fed4
AN		 5944 if (last_sector >= mddev->dev_sectors)
5945 last_sector = mddev->dev_sectors - 1;
52c03291 5946 while (first_sector <= last_sector) {
6d036f7d 5947 sh = raid5_get_active_stripe(conf, first_sector, 1, 0, 1);
52c03291
N		 5948 set_bit(STRIPE_EXPAND_SOURCE, &sh->state);
5949 set_bit(STRIPE_HANDLE, &sh->state);
6d036f7d 5950 raid5_release_stripe(sh);
52c03291
N		 5951 first_sector += STRIPE_SECTORS;
5952 }
ab69ae12
N		 5953 /* Now that the sources are clearly marked, we can release
5954 * the destination stripes
5955 */
5956 while (!list_empty(&stripes)) {
5957 sh = list_entry(stripes.next, struct stripe_head, lru);
5958 list_del_init(&sh->lru);
6d036f7d 5959 raid5_release_stripe(sh);
ab69ae12 5960 }
c6207277
N		 5961 /* If this takes us to the resync_max point where we have to pause,
5962 * then we need to write out the superblock.
5963 */
7a661381 5964 sector_nr += reshape_sectors;
92140480
N		 5965 retn = reshape_sectors;
5966finish:
c5e19d90
N		 5967 if (mddev->curr_resync_completed > mddev->resync_max ||
5968 (sector_nr - mddev->curr_resync_completed) * 2
c03f6a19 5969 >= mddev->resync_max - mddev->curr_resync_completed) {
c6207277
N		 5970 /* Cannot proceed until we've updated the superblock... */
5971 wait_event(conf->wait_for_overlap,
c91abf5a
N		 5972 atomic_read(&conf->reshape_stripes) == 0
5973 || test_bit(MD_RECOVERY_INTR, &mddev->recovery));
5974 if (atomic_read(&conf->reshape_stripes) != 0)
5975 goto ret;
fef9c61f 5976 mddev->reshape_position = conf->reshape_progress;
75d3da43 5977 mddev->curr_resync_completed = sector_nr;
db0505d3
N		 5978 if (!mddev->reshape_backwards)
5979 /* Can update recovery_offset */
5980 rdev_for_each(rdev, mddev)
5981 if (rdev->raid_disk >= 0 &&
5982 !test_bit(Journal, &rdev->flags) &&
5983 !test_bit(In_sync, &rdev->flags) &&
5984 rdev->recovery_offset < sector_nr)
5985 rdev->recovery_offset = sector_nr;
c8f517c4 5986 conf->reshape_checkpoint = jiffies;
2953079c 5987 set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
c6207277
N		 5988 md_wakeup_thread(mddev->thread);
5989 wait_event(mddev->sb_wait,
2953079c 5990 !test_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags)
c91abf5a
N		 5991 || test_bit(MD_RECOVERY_INTR, &mddev->recovery));
5992 if (test_bit(MD_RECOVERY_INTR, &mddev->recovery))
5993 goto ret;
c6207277 5994 spin_lock_irq(&conf->device_lock);
fef9c61f 5995 conf->reshape_safe = mddev->reshape_position;
c6207277
N		 5996 spin_unlock_irq(&conf->device_lock);
5997 wake_up(&conf->wait_for_overlap);
acb180b0 5998 sysfs_notify(&mddev->kobj, NULL, "sync_completed");
c6207277 5999 }
c91abf5a 6000ret:
92140480 6001 return retn;
52c03291
N		 6002}
6003
849674e4
SL		 6004static inline sector_t raid5_sync_request(struct mddev *mddev, sector_t sector_nr,
6005 int *skipped)
52c03291 6006{
d1688a6d 6007 struct r5conf *conf = mddev->private;
52c03291 6008 struct stripe_head *sh;
58c0fed4 6009 sector_t max_sector = mddev->dev_sectors;
57dab0bd 6010 sector_t sync_blocks;
16a53ecc
N		 6011 int still_degraded = 0;
6012 int i;
1da177e4 6013
72626685 6014 if (sector_nr >= max_sector) {
1da177e4 6015 /* just being told to finish up .. nothing much to do */
cea9c228 6016
29269553
N		 6017 if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)) {
6018 end_reshape(conf);
6019 return 0;
6020 }
72626685
N		 6021
6022 if (mddev->curr_resync < max_sector) /* aborted */
6023 bitmap_end_sync(mddev->bitmap, mddev->curr_resync,
6024 &sync_blocks, 1);
16a53ecc 6025 else /* completed sync */
72626685
N		 6026 conf->fullsync = 0;
6027 bitmap_close_sync(mddev->bitmap);
6028
1da177e4
LT		 6029 return 0;
6030 }
ccfcc3c1 6031
64bd660b
N		 6032 /* Allow raid5_quiesce to complete */
6033 wait_event(conf->wait_for_overlap, conf->quiesce != 2);
6034
52c03291
N		 6035 if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
6036 return reshape_request(mddev, sector_nr, skipped);
f6705578 6037
c6207277
N		 6038 /* No need to check resync_max as we never do more than one
6039 * stripe, and as resync_max will always be on a chunk boundary,
6040 * if the check in md_do_sync didn't fire, there is no chance
6041 * of overstepping resync_max here
6042 */
6043
16a53ecc 6044 /* if there is too many failed drives and we are trying
1da177e4
LT		 6045 * to resync, then assert that we are finished, because there is
6046 * nothing we can do.
6047 */
3285edf1 6048 if (mddev->degraded >= conf->max_degraded &&
16a53ecc 6049 test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
58c0fed4 6050 sector_t rv = mddev->dev_sectors - sector_nr;
57afd89f 6051 *skipped = 1;
1da177e4
LT		 6052 return rv;
6053 }
6f608040 6054 if (!test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery) &&
6055 !conf->fullsync &&
6056 !bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, 1) &&
6057 sync_blocks >= STRIPE_SECTORS) {
72626685
N		 6058 /* we can skip this block, and probably more */
6059 sync_blocks /= STRIPE_SECTORS;
6060 *skipped = 1;
6061 return sync_blocks * STRIPE_SECTORS; /* keep things rounded to whole stripes */
6062 }
1da177e4 6063
c40f341f 6064 bitmap_cond_end_sync(mddev->bitmap, sector_nr, false);
b47490c9 6065
6d036f7d 6066 sh = raid5_get_active_stripe(conf, sector_nr, 0, 1, 0);
1da177e4 6067 if (sh == NULL) {
6d036f7d 6068 sh = raid5_get_active_stripe(conf, sector_nr, 0, 0, 0);
1da177e4 6069 /* make sure we don't swamp the stripe cache if someone else
16a53ecc 6070 * is trying to get access
1da177e4 6071 */
66c006a5 6072 schedule_timeout_uninterruptible(1);
1da177e4 6073 }
16a53ecc 6074 /* Need to check if array will still be degraded after recovery/resync
16d9cfab
EM		 6075 * Note in case of > 1 drive failures it's possible we're rebuilding
6076 * one drive while leaving another faulty drive in array.
16a53ecc 6077 */
16d9cfab
EM		 6078 rcu_read_lock();
6079 for (i = 0; i < conf->raid_disks; i++) {
6aa7de05 6080 struct md_rdev *rdev = READ_ONCE(conf->disks[i].rdev);
16d9cfab
EM		 6081
6082 if (rdev == NULL || test_bit(Faulty, &rdev->flags))
16a53ecc 6083 still_degraded = 1;
16d9cfab
EM		 6084 }
6085 rcu_read_unlock();
16a53ecc
N		 6086
6087 bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, still_degraded);
6088
83206d66 6089 set_bit(STRIPE_SYNC_REQUESTED, &sh->state);
053f5b65 6090 set_bit(STRIPE_HANDLE, &sh->state);
1da177e4 6091
6d036f7d 6092 raid5_release_stripe(sh);
1da177e4
LT		 6093
6094 return STRIPE_SECTORS;
6095}
6096
0472a42b
N		 6097static int retry_aligned_read(struct r5conf *conf, struct bio *raid_bio,
6098 unsigned int offset)
46031f9a
RBJ		 6099{
6100 /* We may not be able to submit a whole bio at once as there
6101 * may not be enough stripe_heads available.
6102 * We cannot pre-allocate enough stripe_heads as we may need
6103 * more than exist in the cache (if we allow ever large chunks).
6104 * So we do one stripe head at a time and record in
6105 * ->bi_hw_segments how many have been done.
6106 *
6107 * We *know* that this entire raid_bio is in one chunk, so
6108 * it will be only one 'dd_idx' and only need one call to raid5_compute_sector.
6109 */
6110 struct stripe_head *sh;
911d4ee8 6111 int dd_idx;
46031f9a
RBJ		 6112 sector_t sector, logical_sector, last_sector;
6113 int scnt = 0;
46031f9a
RBJ		 6114 int handled = 0;
6115
4f024f37
KO		 6116 logical_sector = raid_bio->bi_iter.bi_sector &
6117 ~((sector_t)STRIPE_SECTORS-1);
112bf897 6118 sector = raid5_compute_sector(conf, logical_sector,
911d4ee8 6119 0, &dd_idx, NULL);
f73a1c7d 6120 last_sector = bio_end_sector(raid_bio);
46031f9a
RBJ		 6121
6122 for (; logical_sector < last_sector;
387bb173
NB		 6123 logical_sector += STRIPE_SECTORS,
6124 sector += STRIPE_SECTORS,
6125 scnt++) {
46031f9a 6126
0472a42b 6127 if (scnt < offset)
46031f9a
RBJ		 6128 /* already done this stripe */
6129 continue;
6130
6d036f7d 6131 sh = raid5_get_active_stripe(conf, sector, 0, 1, 1);
46031f9a
RBJ		 6132
6133 if (!sh) {
6134 /* failed to get a stripe - must wait */
46031f9a 6135 conf->retry_read_aligned = raid_bio;
0472a42b 6136 conf->retry_read_offset = scnt;
46031f9a
RBJ		 6137 return handled;
6138 }
6139
da41ba65 6140 if (!add_stripe_bio(sh, raid_bio, dd_idx, 0, 0)) {
6d036f7d 6141 raid5_release_stripe(sh);
387bb173 6142 conf->retry_read_aligned = raid_bio;
0472a42b 6143 conf->retry_read_offset = scnt;
387bb173
NB		 6144 return handled;
6145 }
6146
3f9e7c14 6147 set_bit(R5_ReadNoMerge, &sh->dev[dd_idx].flags);
36d1c647 6148 handle_stripe(sh);
6d036f7d 6149 raid5_release_stripe(sh);
46031f9a
RBJ		 6150 handled++;
6151 }
016c76ac
N		 6152
6153 bio_endio(raid_bio);
6154
46031f9a 6155 if (atomic_dec_and_test(&conf->active_aligned_reads))
b1b46486 6156 wake_up(&conf->wait_for_quiescent);
46031f9a
RBJ		 6157 return handled;
6158}
6159
bfc90cb0 6160static int handle_active_stripes(struct r5conf *conf, int group,
566c09c5
SL		 6161 struct r5worker *worker,
6162 struct list_head *temp_inactive_list)
46a06401
SL		 6163{
6164 struct stripe_head *batch[MAX_STRIPE_BATCH], *sh;
566c09c5
SL		 6165 int i, batch_size = 0, hash;
6166 bool release_inactive = false;
46a06401
SL		 6167
6168 while (batch_size < MAX_STRIPE_BATCH &&
851c30c9 6169 (sh = __get_priority_stripe(conf, group)) != NULL)
46a06401
SL		 6170 batch[batch_size++] = sh;
6171
566c09c5
SL		 6172 if (batch_size == 0) {
6173 for (i = 0; i < NR_STRIPE_HASH_LOCKS; i++)
6174 if (!list_empty(temp_inactive_list + i))
6175 break;
a8c34f91
SL		 6176 if (i == NR_STRIPE_HASH_LOCKS) {
6177 spin_unlock_irq(&conf->device_lock);
1532d9e8 6178 log_flush_stripe_to_raid(conf);
a8c34f91 6179 spin_lock_irq(&conf->device_lock);
566c09c5 6180 return batch_size;
a8c34f91 6181 }
566c09c5
SL		 6182 release_inactive = true;
6183 }
46a06401
SL		 6184 spin_unlock_irq(&conf->device_lock);
6185
566c09c5
SL		 6186 release_inactive_stripe_list(conf, temp_inactive_list,
6187 NR_STRIPE_HASH_LOCKS);
6188
a8c34f91 6189 r5l_flush_stripe_to_raid(conf->log);
566c09c5
SL		 6190 if (release_inactive) {
6191 spin_lock_irq(&conf->device_lock);
6192 return 0;
6193 }
6194
46a06401
SL		 6195 for (i = 0; i < batch_size; i++)
6196 handle_stripe(batch[i]);
ff875738 6197 log_write_stripe_run(conf);
46a06401
SL		 6198
6199 cond_resched();
6200
6201 spin_lock_irq(&conf->device_lock);
566c09c5
SL		 6202 for (i = 0; i < batch_size; i++) {
6203 hash = batch[i]->hash_lock_index;
6204 __release_stripe(conf, batch[i], &temp_inactive_list[hash]);
6205 }
46a06401
SL		 6206 return batch_size;
6207}
46031f9a 6208
851c30c9
SL		 6209static void raid5_do_work(struct work_struct *work)
6210{
6211 struct r5worker *worker = container_of(work, struct r5worker, work);
6212 struct r5worker_group *group = worker->group;
6213 struct r5conf *conf = group->conf;
16d997b7 6214 struct mddev *mddev = conf->mddev;
851c30c9
SL		 6215 int group_id = group - conf->worker_groups;
6216 int handled;
6217 struct blk_plug plug;
6218
6219 pr_debug("+++ raid5worker active\n");
6220
6221 blk_start_plug(&plug);
6222 handled = 0;
6223 spin_lock_irq(&conf->device_lock);
6224 while (1) {
6225 int batch_size, released;
6226
566c09c5 6227 released = release_stripe_list(conf, worker->temp_inactive_list);
851c30c9 6228
566c09c5
SL		 6229 batch_size = handle_active_stripes(conf, group_id, worker,
6230 worker->temp_inactive_list);
bfc90cb0 6231 worker->working = false;
851c30c9
SL		 6232 if (!batch_size && !released)
6233 break;
6234 handled += batch_size;
16d997b7
N		 6235 wait_event_lock_irq(mddev->sb_wait,
6236 !test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags),
6237 conf->device_lock);
851c30c9
SL		 6238 }
6239 pr_debug("%d stripes handled\n", handled);
6240
6241 spin_unlock_irq(&conf->device_lock);
7e96d559 6242
9c72a18e
SL		 6243 flush_deferred_bios(conf);
6244
6245 r5l_flush_stripe_to_raid(conf->log);
6246
7e96d559 6247 async_tx_issue_pending_all();
851c30c9
SL		 6248 blk_finish_plug(&plug);
6249
6250 pr_debug("--- raid5worker inactive\n");
6251}
6252
1da177e4
LT		 6253/*
6254 * This is our raid5 kernel thread.
6255 *
6256 * We scan the hash table for stripes which can be handled now.
6257 * During the scan, completed stripes are saved for us by the interrupt
6258 * handler, so that they will not have to wait for our next wakeup.
6259 */
4ed8731d 6260static void raid5d(struct md_thread *thread)
1da177e4 6261{
4ed8731d 6262 struct mddev *mddev = thread->mddev;
d1688a6d 6263 struct r5conf *conf = mddev->private;
1da177e4 6264 int handled;
e1dfa0a2 6265 struct blk_plug plug;
1da177e4 6266
45b4233c 6267 pr_debug("+++ raid5d active\n");
1da177e4
LT		 6268
6269 md_check_recovery(mddev);
1da177e4 6270
e1dfa0a2 6271 blk_start_plug(&plug);
1da177e4
LT		 6272 handled = 0;
6273 spin_lock_irq(&conf->device_lock);
6274 while (1) {
46031f9a 6275 struct bio *bio;
773ca82f 6276 int batch_size, released;
0472a42b 6277 unsigned int offset;
773ca82f 6278
566c09c5 6279 released = release_stripe_list(conf, conf->temp_inactive_list);
edbe83ab
N		 6280 if (released)
6281 clear_bit(R5_DID_ALLOC, &conf->cache_state);
1da177e4 6282
0021b7bc 6283 if (
7c13edc8
N		 6284 !list_empty(&conf->bitmap_list)) {
6285 /* Now is a good time to flush some bitmap updates */
6286 conf->seq_flush++;
700e432d 6287 spin_unlock_irq(&conf->device_lock);
72626685 6288 bitmap_unplug(mddev->bitmap);
700e432d 6289 spin_lock_irq(&conf->device_lock);
7c13edc8 6290 conf->seq_write = conf->seq_flush;
566c09c5 6291 activate_bit_delay(conf, conf->temp_inactive_list);
72626685 6292 }
0021b7bc 6293 raid5_activate_delayed(conf);
72626685 6294
0472a42b 6295 while ((bio = remove_bio_from_retry(conf, &offset))) {
46031f9a
RBJ		 6296 int ok;
6297 spin_unlock_irq(&conf->device_lock);
0472a42b 6298 ok = retry_aligned_read(conf, bio, offset);
46031f9a
RBJ		 6299 spin_lock_irq(&conf->device_lock);
6300 if (!ok)
6301 break;
6302 handled++;
6303 }
6304
566c09c5
SL		 6305 batch_size = handle_active_stripes(conf, ANY_GROUP, NULL,
6306 conf->temp_inactive_list);
773ca82f 6307 if (!batch_size && !released)
1da177e4 6308 break;
46a06401 6309 handled += batch_size;
1da177e4 6310
2953079c 6311 if (mddev->sb_flags & ~(1 << MD_SB_CHANGE_PENDING)) {
46a06401 6312 spin_unlock_irq(&conf->device_lock);
de393cde 6313 md_check_recovery(mddev);
46a06401
SL		 6314 spin_lock_irq(&conf->device_lock);
6315 }
1da177e4 6316 }
45b4233c 6317 pr_debug("%d stripes handled\n", handled);
1da177e4
LT		 6318
6319 spin_unlock_irq(&conf->device_lock);
2d5b569b
N		 6320 if (test_and_clear_bit(R5_ALLOC_MORE, &conf->cache_state) &&
6321 mutex_trylock(&conf->cache_size_mutex)) {
edbe83ab
N		 6322 grow_one_stripe(conf, __GFP_NOWARN);
6323 /* Set flag even if allocation failed. This helps
6324 * slow down allocation requests when mem is short
6325 */
6326 set_bit(R5_DID_ALLOC, &conf->cache_state);
2d5b569b 6327 mutex_unlock(&conf->cache_size_mutex);
edbe83ab 6328 }
1da177e4 6329
765d704d
SL		 6330 flush_deferred_bios(conf);
6331
0576b1c6
SL		 6332 r5l_flush_stripe_to_raid(conf->log);
6333
c9f21aaf 6334 async_tx_issue_pending_all();
e1dfa0a2 6335 blk_finish_plug(&plug);
1da177e4 6336
45b4233c 6337 pr_debug("--- raid5d inactive\n");
1da177e4
LT		 6338}
6339
3f294f4f 6340static ssize_t
fd01b88c 6341raid5_show_stripe_cache_size(struct mddev *mddev, char *page)
3f294f4f 6342{
7b1485ba
N		 6343 struct r5conf *conf;
6344 int ret = 0;
6345 spin_lock(&mddev->lock);
6346 conf = mddev->private;
96de1e66 6347 if (conf)
edbe83ab 6348 ret = sprintf(page, "%d\n", conf->min_nr_stripes);
7b1485ba
N		 6349 spin_unlock(&mddev->lock);
6350 return ret;
3f294f4f
N		 6351}
6352
c41d4ac4 6353int
fd01b88c 6354raid5_set_cache_size(struct mddev *mddev, int size)
3f294f4f 6355{
d1688a6d 6356 struct r5conf *conf = mddev->private;
b5470dc5 6357
c41d4ac4 6358 if (size <= 16 || size > 32768)
3f294f4f 6359 return -EINVAL;
486f0644 6360
edbe83ab 6361 conf->min_nr_stripes = size;
2d5b569b 6362 mutex_lock(&conf->cache_size_mutex);
486f0644
N		 6363 while (size < conf->max_nr_stripes &&
6364 drop_one_stripe(conf))
6365 ;
2d5b569b 6366 mutex_unlock(&conf->cache_size_mutex);
486f0644 6367
2214c260 6368 md_allow_write(mddev);
486f0644 6369
2d5b569b 6370 mutex_lock(&conf->cache_size_mutex);
486f0644
N		 6371 while (size > conf->max_nr_stripes)
6372 if (!grow_one_stripe(conf, GFP_KERNEL))
6373 break;
2d5b569b 6374 mutex_unlock(&conf->cache_size_mutex);
486f0644 6375
c41d4ac4
N		 6376 return 0;
6377}
6378EXPORT_SYMBOL(raid5_set_cache_size);
6379
6380static ssize_t
fd01b88c 6381raid5_store_stripe_cache_size(struct mddev *mddev, const char *page, size_t len)
c41d4ac4 6382{
6791875e 6383 struct r5conf *conf;
c41d4ac4
N		 6384 unsigned long new;
6385 int err;
6386
6387 if (len >= PAGE_SIZE)
6388 return -EINVAL;
b29bebd6 6389 if (kstrtoul(page, 10, &new))
c41d4ac4 6390 return -EINVAL;
6791875e 6391 err = mddev_lock(mddev);
c41d4ac4
N		 6392 if (err)
6393 return err;
6791875e
N		 6394 conf = mddev->private;
6395 if (!conf)
6396 err = -ENODEV;
6397 else
6398 err = raid5_set_cache_size(mddev, new);
6399 mddev_unlock(mddev);
6400
6401 return err ?: len;
3f294f4f 6402}
007583c9 6403
96de1e66
N		 6404static struct md_sysfs_entry
6405raid5_stripecache_size = __ATTR(stripe_cache_size, S_IRUGO | S_IWUSR,
6406 raid5_show_stripe_cache_size,
6407 raid5_store_stripe_cache_size);
3f294f4f 6408
d06f191f
MS		 6409static ssize_t
6410raid5_show_rmw_level(struct mddev *mddev, char *page)
6411{
6412 struct r5conf *conf = mddev->private;
6413 if (conf)
6414 return sprintf(page, "%d\n", conf->rmw_level);
6415 else
6416 return 0;
6417}
6418
6419static ssize_t
6420raid5_store_rmw_level(struct mddev *mddev, const char *page, size_t len)
6421{
6422 struct r5conf *conf = mddev->private;
6423 unsigned long new;
6424
6425 if (!conf)
6426 return -ENODEV;
6427
6428 if (len >= PAGE_SIZE)
6429 return -EINVAL;
6430
6431 if (kstrtoul(page, 10, &new))
6432 return -EINVAL;
6433
6434 if (new != PARITY_DISABLE_RMW && !raid6_call.xor_syndrome)
6435 return -EINVAL;
6436
6437 if (new != PARITY_DISABLE_RMW &&
6438 new != PARITY_ENABLE_RMW &&
6439 new != PARITY_PREFER_RMW)
6440 return -EINVAL;
6441
6442 conf->rmw_level = new;
6443 return len;
6444}
6445
6446static struct md_sysfs_entry
6447raid5_rmw_level = __ATTR(rmw_level, S_IRUGO | S_IWUSR,
6448 raid5_show_rmw_level,
6449 raid5_store_rmw_level);
6450
6451
8b3e6cdc 6452static ssize_t
fd01b88c 6453raid5_show_preread_threshold(struct mddev *mddev, char *page)
8b3e6cdc 6454{
7b1485ba
N		 6455 struct r5conf *conf;
6456 int ret = 0;
6457 spin_lock(&mddev->lock);
6458 conf = mddev->private;
8b3e6cdc 6459 if (conf)
7b1485ba
N		 6460 ret = sprintf(page, "%d\n", conf->bypass_threshold);
6461 spin_unlock(&mddev->lock);
6462 return ret;
8b3e6cdc
DW		 6463}
6464
6465static ssize_t
fd01b88c 6466raid5_store_preread_threshold(struct mddev *mddev, const char *page, size_t len)
8b3e6cdc 6467{
6791875e 6468 struct r5conf *conf;
4ef197d8 6469 unsigned long new;
6791875e
N		 6470 int err;
6471
8b3e6cdc
DW		 6472 if (len >= PAGE_SIZE)
6473 return -EINVAL;
b29bebd6 6474 if (kstrtoul(page, 10, &new))
8b3e6cdc 6475 return -EINVAL;
6791875e
N		 6476
6477 err = mddev_lock(mddev);
6478 if (err)
6479 return err;
6480 conf = mddev->private;
6481 if (!conf)
6482 err = -ENODEV;
edbe83ab 6483 else if (new > conf->min_nr_stripes)
6791875e
N		 6484 err = -EINVAL;
6485 else
6486 conf->bypass_threshold = new;
6487 mddev_unlock(mddev);
6488 return err ?: len;
8b3e6cdc
DW		 6489}
6490
6491static struct md_sysfs_entry
6492raid5_preread_bypass_threshold = __ATTR(preread_bypass_threshold,
6493 S_IRUGO | S_IWUSR,
6494 raid5_show_preread_threshold,
6495 raid5_store_preread_threshold);
6496
d592a996
SL		 6497static ssize_t
6498raid5_show_skip_copy(struct mddev *mddev, char *page)
6499{
7b1485ba
N		 6500 struct r5conf *conf;
6501 int ret = 0;
6502 spin_lock(&mddev->lock);
6503 conf = mddev->private;
d592a996 6504 if (conf)
7b1485ba
N		 6505 ret = sprintf(page, "%d\n", conf->skip_copy);
6506 spin_unlock(&mddev->lock);
6507 return ret;
d592a996
SL		 6508}
6509
6510static ssize_t
6511raid5_store_skip_copy(struct mddev *mddev, const char *page, size_t len)
6512{
6791875e 6513 struct r5conf *conf;
d592a996 6514 unsigned long new;
6791875e
N		 6515 int err;
6516
d592a996
SL		 6517 if (len >= PAGE_SIZE)
6518 return -EINVAL;
d592a996
SL		 6519 if (kstrtoul(page, 10, &new))
6520 return -EINVAL;
6521 new = !!new;
6791875e
N		 6522
6523 err = mddev_lock(mddev);
6524 if (err)
6525 return err;
6526 conf = mddev->private;
6527 if (!conf)
6528 err = -ENODEV;
6529 else if (new != conf->skip_copy) {
6530 mddev_suspend(mddev);
6531 conf->skip_copy = new;
6532 if (new)
dc3b17cc 6533 mddev->queue->backing_dev_info->capabilities |=
6791875e
N		 6534 BDI_CAP_STABLE_WRITES;
6535 else
dc3b17cc 6536 mddev->queue->backing_dev_info->capabilities &=
6791875e
N		 6537 ~BDI_CAP_STABLE_WRITES;
6538 mddev_resume(mddev);
6539 }
6540 mddev_unlock(mddev);
6541 return err ?: len;
d592a996
SL		 6542}
6543
6544static struct md_sysfs_entry
6545raid5_skip_copy = __ATTR(skip_copy, S_IRUGO | S_IWUSR,
6546 raid5_show_skip_copy,
6547 raid5_store_skip_copy);
6548
3f294f4f 6549static ssize_t
fd01b88c 6550stripe_cache_active_show(struct mddev *mddev, char *page)
3f294f4f 6551{
d1688a6d 6552 struct r5conf *conf = mddev->private;
96de1e66
N		 6553 if (conf)
6554 return sprintf(page, "%d\n", atomic_read(&conf->active_stripes));
6555 else
6556 return 0;
3f294f4f
N		 6557}
6558
96de1e66
N		 6559static struct md_sysfs_entry
6560raid5_stripecache_active = __ATTR_RO(stripe_cache_active);
3f294f4f 6561
b721420e
SL		 6562static ssize_t
6563raid5_show_group_thread_cnt(struct mddev *mddev, char *page)
6564{
7b1485ba
N		 6565 struct r5conf *conf;
6566 int ret = 0;
6567 spin_lock(&mddev->lock);
6568 conf = mddev->private;
b721420e 6569 if (conf)
7b1485ba
N		 6570 ret = sprintf(page, "%d\n", conf->worker_cnt_per_group);
6571 spin_unlock(&mddev->lock);
6572 return ret;
b721420e
SL		 6573}
6574
60aaf933 6575static int alloc_thread_groups(struct r5conf *conf, int cnt,
6576 int *group_cnt,
6577 int *worker_cnt_per_group,
6578 struct r5worker_group **worker_groups);
b721420e
SL		 6579static ssize_t
6580raid5_store_group_thread_cnt(struct mddev *mddev, const char *page, size_t len)
6581{
6791875e 6582 struct r5conf *conf;
7d5d7b50 6583 unsigned int new;
b721420e 6584 int err;
60aaf933 6585 struct r5worker_group *new_groups, *old_groups;
6586 int group_cnt, worker_cnt_per_group;
b721420e
SL		 6587
6588 if (len >= PAGE_SIZE)
6589 return -EINVAL;
7d5d7b50
SL		 6590 if (kstrtouint(page, 10, &new))
6591 return -EINVAL;
6592 /* 8192 should be big enough */
6593 if (new > 8192)
b721420e
SL		 6594 return -EINVAL;
6595
6791875e
N		 6596 err = mddev_lock(mddev);
6597 if (err)
6598 return err;
6599 conf = mddev->private;
6600 if (!conf)
6601 err = -ENODEV;
6602 else if (new != conf->worker_cnt_per_group) {
6603 mddev_suspend(mddev);
b721420e 6604
6791875e
N		 6605 old_groups = conf->worker_groups;
6606 if (old_groups)
6607 flush_workqueue(raid5_wq);
d206dcfa 6608
6791875e
N		 6609 err = alloc_thread_groups(conf, new,
6610 &group_cnt, &worker_cnt_per_group,
6611 &new_groups);
6612 if (!err) {
6613 spin_lock_irq(&conf->device_lock);
6614 conf->group_cnt = group_cnt;
6615 conf->worker_cnt_per_group = worker_cnt_per_group;
6616 conf->worker_groups = new_groups;
6617 spin_unlock_irq(&conf->device_lock);
b721420e 6618
6791875e
N		 6619 if (old_groups)
6620 kfree(old_groups[0].workers);
6621 kfree(old_groups);
6622 }
6623 mddev_resume(mddev);
b721420e 6624 }
6791875e 6625 mddev_unlock(mddev);
b721420e 6626
6791875e 6627 return err ?: len;
b721420e
SL		 6628}
6629
6630static struct md_sysfs_entry
6631raid5_group_thread_cnt = __ATTR(group_thread_cnt, S_IRUGO | S_IWUSR,
6632 raid5_show_group_thread_cnt,
6633 raid5_store_group_thread_cnt);
6634
007583c9 6635static struct attribute *raid5_attrs[] = {
3f294f4f
N		 6636 &raid5_stripecache_size.attr,
6637 &raid5_stripecache_active.attr,
8b3e6cdc 6638 &raid5_preread_bypass_threshold.attr,
b721420e 6639 &raid5_group_thread_cnt.attr,
d592a996 6640 &raid5_skip_copy.attr,
d06f191f 6641 &raid5_rmw_level.attr,
2c7da14b 6642 &r5c_journal_mode.attr,
3f294f4f
N		 6643 NULL,
6644};
007583c9
N		 6645static struct attribute_group raid5_attrs_group = {
6646 .name = NULL,
6647 .attrs = raid5_attrs,
3f294f4f
N		 6648};
6649
60aaf933 6650static int alloc_thread_groups(struct r5conf *conf, int cnt,
6651 int *group_cnt,
6652 int *worker_cnt_per_group,
6653 struct r5worker_group **worker_groups)
851c30c9 6654{
566c09c5 6655 int i, j, k;
851c30c9
SL		 6656 ssize_t size;
6657 struct r5worker *workers;
6658
60aaf933 6659 *worker_cnt_per_group = cnt;
851c30c9 6660 if (cnt == 0) {
60aaf933 6661 *group_cnt = 0;
6662 *worker_groups = NULL;
851c30c9
SL		 6663 return 0;
6664 }
60aaf933 6665 *group_cnt = num_possible_nodes();
851c30c9 6666 size = sizeof(struct r5worker) * cnt;
6396bb22
KC		 6667 workers = kcalloc(size, *group_cnt, GFP_NOIO);
6668 *worker_groups = kcalloc(*group_cnt, sizeof(struct r5worker_group),
6669 GFP_NOIO);
60aaf933 6670 if (!*worker_groups || !workers) {
851c30c9 6671 kfree(workers);
60aaf933 6672 kfree(*worker_groups);
851c30c9
SL		 6673 return -ENOMEM;
6674 }
6675
60aaf933 6676 for (i = 0; i < *group_cnt; i++) {
851c30c9
SL		 6677 struct r5worker_group *group;
6678
0c775d52 6679 group = &(*worker_groups)[i];
851c30c9 6680 INIT_LIST_HEAD(&group->handle_list);
535ae4eb 6681 INIT_LIST_HEAD(&group->loprio_list);
851c30c9
SL		 6682 group->conf = conf;
6683 group->workers = workers + i * cnt;
6684
6685 for (j = 0; j < cnt; j++) {
566c09c5
SL		 6686 struct r5worker *worker = group->workers + j;
6687 worker->group = group;
6688 INIT_WORK(&worker->work, raid5_do_work);
6689
6690 for (k = 0; k < NR_STRIPE_HASH_LOCKS; k++)
6691 INIT_LIST_HEAD(worker->temp_inactive_list + k);
851c30c9
SL		 6692 }
6693 }
6694
6695 return 0;
6696}
6697
6698static void free_thread_groups(struct r5conf *conf)
6699{
6700 if (conf->worker_groups)
6701 kfree(conf->worker_groups[0].workers);
6702 kfree(conf->worker_groups);
6703 conf->worker_groups = NULL;
6704}
6705
80c3a6ce 6706static sector_t
fd01b88c 6707raid5_size(struct mddev *mddev, sector_t sectors, int raid_disks)
80c3a6ce 6708{
d1688a6d 6709 struct r5conf *conf = mddev->private;
80c3a6ce
DW		 6710
6711 if (!sectors)
6712 sectors = mddev->dev_sectors;
5e5e3e78 6713 if (!raid_disks)
7ec05478 6714 /* size is defined by the smallest of previous and new size */
5e5e3e78 6715 raid_disks = min(conf->raid_disks, conf->previous_raid_disks);
80c3a6ce 6716
3cb5edf4
N		 6717 sectors &= ~((sector_t)conf->chunk_sectors - 1);
6718 sectors &= ~((sector_t)conf->prev_chunk_sectors - 1);
80c3a6ce
DW		 6719 return sectors * (raid_disks - conf->max_degraded);
6720}
6721
789b5e03
ON		 6722static void free_scratch_buffer(struct r5conf *conf, struct raid5_percpu *percpu)
6723{
6724 safe_put_page(percpu->spare_page);
46d5b785 6725 if (percpu->scribble)
6726 flex_array_free(percpu->scribble);
789b5e03
ON		 6727 percpu->spare_page = NULL;
6728 percpu->scribble = NULL;
6729}
6730
6731static int alloc_scratch_buffer(struct r5conf *conf, struct raid5_percpu *percpu)
6732{
6733 if (conf->level == 6 && !percpu->spare_page)
6734 percpu->spare_page = alloc_page(GFP_KERNEL);
6735 if (!percpu->scribble)
46d5b785 6736 percpu->scribble = scribble_alloc(max(conf->raid_disks,
738a2738
N		 6737 conf->previous_raid_disks),
6738 max(conf->chunk_sectors,
6739 conf->prev_chunk_sectors)
6740 / STRIPE_SECTORS,
6741 GFP_KERNEL);
789b5e03
ON		 6742
6743 if (!percpu->scribble || (conf->level == 6 && !percpu->spare_page)) {
6744 free_scratch_buffer(conf, percpu);
6745 return -ENOMEM;
6746 }
6747
6748 return 0;
6749}
6750
29c6d1bb 6751static int raid456_cpu_dead(unsigned int cpu, struct hlist_node *node)
36d1c647 6752{
29c6d1bb
SAS		 6753 struct r5conf *conf = hlist_entry_safe(node, struct r5conf, node);
6754
6755 free_scratch_buffer(conf, per_cpu_ptr(conf->percpu, cpu));
6756 return 0;
6757}
36d1c647 6758
29c6d1bb
SAS		 6759static void raid5_free_percpu(struct r5conf *conf)
6760{
36d1c647
DW		 6761 if (!conf->percpu)
6762 return;
6763
29c6d1bb 6764 cpuhp_state_remove_instance(CPUHP_MD_RAID5_PREPARE, &conf->node);
36d1c647
DW		 6765 free_percpu(conf->percpu);
6766}
6767
d1688a6d 6768static void free_conf(struct r5conf *conf)
95fc17aa 6769{
d7bd398e
SL		 6770 int i;
6771
ff875738
AP		 6772 log_exit(conf);
6773
565e0450 6774 unregister_shrinker(&conf->shrinker);
851c30c9 6775 free_thread_groups(conf);
95fc17aa 6776 shrink_stripes(conf);
36d1c647 6777 raid5_free_percpu(conf);
d7bd398e
SL		 6778 for (i = 0; i < conf->pool_size; i++)
6779 if (conf->disks[i].extra_page)
6780 put_page(conf->disks[i].extra_page);
95fc17aa 6781 kfree(conf->disks);
afeee514 6782 bioset_exit(&conf->bio_split);
95fc17aa 6783 kfree(conf->stripe_hashtbl);
aaf9f12e 6784 kfree(conf->pending_data);
95fc17aa
DW		 6785 kfree(conf);
6786}
6787
29c6d1bb 6788static int raid456_cpu_up_prepare(unsigned int cpu, struct hlist_node *node)
36d1c647 6789{
29c6d1bb 6790 struct r5conf *conf = hlist_entry_safe(node, struct r5conf, node);
36d1c647
DW		 6791 struct raid5_percpu *percpu = per_cpu_ptr(conf->percpu, cpu);
6792
29c6d1bb 6793 if (alloc_scratch_buffer(conf, percpu)) {
cc6167b4
N		 6794 pr_warn("%s: failed memory allocation for cpu%u\n",
6795 __func__, cpu);
29c6d1bb 6796 return -ENOMEM;
36d1c647 6797 }
29c6d1bb 6798 return 0;
36d1c647 6799}
36d1c647 6800
d1688a6d 6801static int raid5_alloc_percpu(struct r5conf *conf)
36d1c647 6802{
789b5e03 6803 int err = 0;
36d1c647 6804
789b5e03
ON		 6805 conf->percpu = alloc_percpu(struct raid5_percpu);
6806 if (!conf->percpu)
36d1c647 6807 return -ENOMEM;
789b5e03 6808
29c6d1bb 6809 err = cpuhp_state_add_instance(CPUHP_MD_RAID5_PREPARE, &conf->node);
27a353c0
SL		 6810 if (!err) {
6811 conf->scribble_disks = max(conf->raid_disks,
6812 conf->previous_raid_disks);
6813 conf->scribble_sectors = max(conf->chunk_sectors,
6814 conf->prev_chunk_sectors);
6815 }
36d1c647
DW		 6816 return err;
6817}
6818
edbe83ab
N		 6819static unsigned long raid5_cache_scan(struct shrinker *shrink,
6820 struct shrink_control *sc)
6821{
6822 struct r5conf *conf = container_of(shrink, struct r5conf, shrinker);
2d5b569b
N		 6823 unsigned long ret = SHRINK_STOP;
6824
6825 if (mutex_trylock(&conf->cache_size_mutex)) {
6826 ret= 0;
49895bcc
N		 6827 while (ret < sc->nr_to_scan &&
6828 conf->max_nr_stripes > conf->min_nr_stripes) {
2d5b569b
N		 6829 if (drop_one_stripe(conf) == 0) {
6830 ret = SHRINK_STOP;
6831 break;
6832 }
6833 ret++;
6834 }
6835 mutex_unlock(&conf->cache_size_mutex);
edbe83ab
N		 6836 }
6837 return ret;
6838}
6839
6840static unsigned long raid5_cache_count(struct shrinker *shrink,
6841 struct shrink_control *sc)
6842{
6843 struct r5conf *conf = container_of(shrink, struct r5conf, shrinker);
6844
6845 if (conf->max_nr_stripes < conf->min_nr_stripes)
6846 /* unlikely, but not impossible */
6847 return 0;
6848 return conf->max_nr_stripes - conf->min_nr_stripes;
6849}
6850
d1688a6d 6851static struct r5conf *setup_conf(struct mddev *mddev)
1da177e4 6852{
d1688a6d 6853 struct r5conf *conf;
5e5e3e78 6854 int raid_disk, memory, max_disks;
3cb03002 6855 struct md_rdev *rdev;
1da177e4 6856 struct disk_info *disk;
0232605d 6857 char pers_name[6];
566c09c5 6858 int i;
60aaf933 6859 int group_cnt, worker_cnt_per_group;
6860 struct r5worker_group *new_group;
afeee514 6861 int ret;
1da177e4 6862
91adb564
N		 6863 if (mddev->new_level != 5
6864 && mddev->new_level != 4
6865 && mddev->new_level != 6) {
cc6167b4
N		 6866 pr_warn("md/raid:%s: raid level not set to 4/5/6 (%d)\n",
6867 mdname(mddev), mddev->new_level);
91adb564 6868 return ERR_PTR(-EIO);
1da177e4 6869 }
91adb564
N		 6870 if ((mddev->new_level == 5
6871 && !algorithm_valid_raid5(mddev->new_layout)) ||
6872 (mddev->new_level == 6
6873 && !algorithm_valid_raid6(mddev->new_layout))) {
cc6167b4
N		 6874 pr_warn("md/raid:%s: layout %d not supported\n",
6875 mdname(mddev), mddev->new_layout);
91adb564 6876 return ERR_PTR(-EIO);
99c0fb5f 6877 }
91adb564 6878 if (mddev->new_level == 6 && mddev->raid_disks < 4) {
cc6167b4
N		 6879 pr_warn("md/raid:%s: not enough configured devices (%d, minimum 4)\n",
6880 mdname(mddev), mddev->raid_disks);
91adb564 6881 return ERR_PTR(-EINVAL);
4bbf3771
N		 6882 }
6883
664e7c41
AN		 6884 if (!mddev->new_chunk_sectors ||
6885 (mddev->new_chunk_sectors << 9) % PAGE_SIZE ||
6886 !is_power_of_2(mddev->new_chunk_sectors)) {
cc6167b4
N		 6887 pr_warn("md/raid:%s: invalid chunk size %d\n",
6888 mdname(mddev), mddev->new_chunk_sectors << 9);
91adb564 6889 return ERR_PTR(-EINVAL);
f6705578
N		 6890 }
6891
d1688a6d 6892 conf = kzalloc(sizeof(struct r5conf), GFP_KERNEL);
91adb564 6893 if (conf == NULL)
1da177e4 6894 goto abort;
aaf9f12e
SL		 6895 INIT_LIST_HEAD(&conf->free_list);
6896 INIT_LIST_HEAD(&conf->pending_list);
6396bb22
KC		 6897 conf->pending_data = kcalloc(PENDING_IO_MAX,
6898 sizeof(struct r5pending_data),
6899 GFP_KERNEL);
aaf9f12e
SL		 6900 if (!conf->pending_data)
6901 goto abort;
6902 for (i = 0; i < PENDING_IO_MAX; i++)
6903 list_add(&conf->pending_data[i].sibling, &conf->free_list);
851c30c9 6904 /* Don't enable multi-threading by default*/
60aaf933 6905 if (!alloc_thread_groups(conf, 0, &group_cnt, &worker_cnt_per_group,
6906 &new_group)) {
6907 conf->group_cnt = group_cnt;
6908 conf->worker_cnt_per_group = worker_cnt_per_group;
6909 conf->worker_groups = new_group;
6910 } else
851c30c9 6911 goto abort;
f5efd45a 6912 spin_lock_init(&conf->device_lock);
c46501b2 6913 seqcount_init(&conf->gen_lock);
2d5b569b 6914 mutex_init(&conf->cache_size_mutex);
b1b46486 6915 init_waitqueue_head(&conf->wait_for_quiescent);
6ab2a4b8 6916 init_waitqueue_head(&conf->wait_for_stripe);
f5efd45a
DW		 6917 init_waitqueue_head(&conf->wait_for_overlap);
6918 INIT_LIST_HEAD(&conf->handle_list);
535ae4eb 6919 INIT_LIST_HEAD(&conf->loprio_list);
f5efd45a
DW		 6920 INIT_LIST_HEAD(&conf->hold_list);
6921 INIT_LIST_HEAD(&conf->delayed_list);
6922 INIT_LIST_HEAD(&conf->bitmap_list);
773ca82f 6923 init_llist_head(&conf->released_stripes);
f5efd45a
DW		 6924 atomic_set(&conf->active_stripes, 0);
6925 atomic_set(&conf->preread_active_stripes, 0);
6926 atomic_set(&conf->active_aligned_reads, 0);
765d704d
SL		 6927 spin_lock_init(&conf->pending_bios_lock);
6928 conf->batch_bio_dispatch = true;
6929 rdev_for_each(rdev, mddev) {
6930 if (test_bit(Journal, &rdev->flags))
6931 continue;
6932 if (blk_queue_nonrot(bdev_get_queue(rdev->bdev))) {
6933 conf->batch_bio_dispatch = false;
6934 break;
6935 }
6936 }
6937
f5efd45a 6938 conf->bypass_threshold = BYPASS_THRESHOLD;
d890fa2b 6939 conf->recovery_disabled = mddev->recovery_disabled - 1;
91adb564
N		 6940
6941 conf->raid_disks = mddev->raid_disks;
6942 if (mddev->reshape_position == MaxSector)
6943 conf->previous_raid_disks = mddev->raid_disks;
6944 else
f6705578 6945 conf->previous_raid_disks = mddev->raid_disks - mddev->delta_disks;
5e5e3e78 6946 max_disks = max(conf->raid_disks, conf->previous_raid_disks);
f6705578 6947
6396bb22 6948 conf->disks = kcalloc(max_disks, sizeof(struct disk_info),
b55e6bfc 6949 GFP_KERNEL);
d7bd398e 6950
b55e6bfc
N		 6951 if (!conf->disks)
6952 goto abort;
9ffae0cf 6953
d7bd398e
SL		 6954 for (i = 0; i < max_disks; i++) {
6955 conf->disks[i].extra_page = alloc_page(GFP_KERNEL);
6956 if (!conf->disks[i].extra_page)
6957 goto abort;
6958 }
6959
afeee514
KO		 6960 ret = bioset_init(&conf->bio_split, BIO_POOL_SIZE, 0, 0);
6961 if (ret)
dd7a8f5d 6962 goto abort;
1da177e4
LT		 6963 conf->mddev = mddev;
6964
fccddba0 6965 if ((conf->stripe_hashtbl = kzalloc(PAGE_SIZE, GFP_KERNEL)) == NULL)
1da177e4 6966 goto abort;
1da177e4 6967
566c09c5
SL		 6968 /* We init hash_locks[0] separately to that it can be used
6969 * as the reference lock in the spin_lock_nest_lock() call
6970 * in lock_all_device_hash_locks_irq in order to convince
6971 * lockdep that we know what we are doing.
6972 */
6973 spin_lock_init(conf->hash_locks);
6974 for (i = 1; i < NR_STRIPE_HASH_LOCKS; i++)
6975 spin_lock_init(conf->hash_locks + i);
6976
6977 for (i = 0; i < NR_STRIPE_HASH_LOCKS; i++)
6978 INIT_LIST_HEAD(conf->inactive_list + i);
6979
6980 for (i = 0; i < NR_STRIPE_HASH_LOCKS; i++)
6981 INIT_LIST_HEAD(conf->temp_inactive_list + i);
6982
1e6d690b
SL		 6983 atomic_set(&conf->r5c_cached_full_stripes, 0);
6984 INIT_LIST_HEAD(&conf->r5c_full_stripe_list);
6985 atomic_set(&conf->r5c_cached_partial_stripes, 0);
6986 INIT_LIST_HEAD(&conf->r5c_partial_stripe_list);
e33fbb9c
SL		 6987 atomic_set(&conf->r5c_flushing_full_stripes, 0);
6988 atomic_set(&conf->r5c_flushing_partial_stripes, 0);
1e6d690b 6989
36d1c647 6990 conf->level = mddev->new_level;
46d5b785 6991 conf->chunk_sectors = mddev->new_chunk_sectors;
36d1c647
DW		 6992 if (raid5_alloc_percpu(conf) != 0)
6993 goto abort;
6994
0c55e022 6995 pr_debug("raid456: run(%s) called.\n", mdname(mddev));
1da177e4 6996
dafb20fa 6997 rdev_for_each(rdev, mddev) {
1da177e4 6998 raid_disk = rdev->raid_disk;
5e5e3e78 6999 if (raid_disk >= max_disks
f2076e7d 7000 || raid_disk < 0 || test_bit(Journal, &rdev->flags))
1da177e4
LT		 7001 continue;
7002 disk = conf->disks + raid_disk;
7003
17045f52
N		 7004 if (test_bit(Replacement, &rdev->flags)) {
7005 if (disk->replacement)
7006 goto abort;
7007 disk->replacement = rdev;
7008 } else {
7009 if (disk->rdev)
7010 goto abort;
7011 disk->rdev = rdev;
7012 }
1da177e4 7013
b2d444d7 7014 if (test_bit(In_sync, &rdev->flags)) {
1da177e4 7015 char b[BDEVNAME_SIZE];
cc6167b4
N		 7016 pr_info("md/raid:%s: device %s operational as raid disk %d\n",
7017 mdname(mddev), bdevname(rdev->bdev, b), raid_disk);
d6b212f4 7018 } else if (rdev->saved_raid_disk != raid_disk)
8c2e870a
NB		 7019 /* Cannot rely on bitmap to complete recovery */
7020 conf->fullsync = 1;
1da177e4
LT		 7021 }
7022
91adb564 7023 conf->level = mddev->new_level;
584acdd4 7024 if (conf->level == 6) {
16a53ecc 7025 conf->max_degraded = 2;
584acdd4
MS		 7026 if (raid6_call.xor_syndrome)
7027 conf->rmw_level = PARITY_ENABLE_RMW;
7028 else
7029 conf->rmw_level = PARITY_DISABLE_RMW;
7030 } else {
16a53ecc 7031 conf->max_degraded = 1;
584acdd4
MS		 7032 conf->rmw_level = PARITY_ENABLE_RMW;
7033 }
91adb564 7034 conf->algorithm = mddev->new_layout;
fef9c61f 7035 conf->reshape_progress = mddev->reshape_position;
e183eaed 7036 if (conf->reshape_progress != MaxSector) {
09c9e5fa 7037 conf->prev_chunk_sectors = mddev->chunk_sectors;
e183eaed 7038 conf->prev_algo = mddev->layout;
5cac6bcb
N		 7039 } else {
7040 conf->prev_chunk_sectors = conf->chunk_sectors;
7041 conf->prev_algo = conf->algorithm;
e183eaed 7042 }
1da177e4 7043
edbe83ab 7044 conf->min_nr_stripes = NR_STRIPES;
ad5b0f76
SL		 7045 if (mddev->reshape_position != MaxSector) {
7046 int stripes = max_t(int,
7047 ((mddev->chunk_sectors << 9) / STRIPE_SIZE) * 4,
7048 ((mddev->new_chunk_sectors << 9) / STRIPE_SIZE) * 4);
7049 conf->min_nr_stripes = max(NR_STRIPES, stripes);
7050 if (conf->min_nr_stripes != NR_STRIPES)
cc6167b4 7051 pr_info("md/raid:%s: force stripe size %d for reshape\n",
ad5b0f76
SL		 7052 mdname(mddev), conf->min_nr_stripes);
7053 }
edbe83ab 7054 memory = conf->min_nr_stripes * (sizeof(struct stripe_head) +
5e5e3e78 7055 max_disks * ((sizeof(struct bio) + PAGE_SIZE))) / 1024;
4bda556a 7056 atomic_set(&conf->empty_inactive_list_nr, NR_STRIPE_HASH_LOCKS);
edbe83ab 7057 if (grow_stripes(conf, conf->min_nr_stripes)) {
cc6167b4
N		 7058 pr_warn("md/raid:%s: couldn't allocate %dkB for buffers\n",
7059 mdname(mddev), memory);
91adb564
N		 7060 goto abort;
7061 } else
cc6167b4 7062 pr_debug("md/raid:%s: allocated %dkB\n", mdname(mddev), memory);
edbe83ab
N		 7063 /*
7064 * Losing a stripe head costs more than the time to refill it,
7065 * it reduces the queue depth and so can hurt throughput.
7066 * So set it rather large, scaled by number of devices.
7067 */
7068 conf->shrinker.seeks = DEFAULT_SEEKS * conf->raid_disks * 4;
7069 conf->shrinker.scan_objects = raid5_cache_scan;
7070 conf->shrinker.count_objects = raid5_cache_count;
7071 conf->shrinker.batch = 128;
7072 conf->shrinker.flags = 0;
6a0f53ff 7073 if (register_shrinker(&conf->shrinker)) {
cc6167b4
N		 7074 pr_warn("md/raid:%s: couldn't register shrinker.\n",
7075 mdname(mddev));
6a0f53ff
CY		 7076 goto abort;
7077 }
1da177e4 7078
0232605d
N		 7079 sprintf(pers_name, "raid%d", mddev->new_level);
7080 conf->thread = md_register_thread(raid5d, mddev, pers_name);
91adb564 7081 if (!conf->thread) {
cc6167b4
N		 7082 pr_warn("md/raid:%s: couldn't allocate thread.\n",
7083 mdname(mddev));
16a53ecc
N		 7084 goto abort;
7085 }
91adb564
N		 7086
7087 return conf;
7088
7089 abort:
7090 if (conf) {
95fc17aa 7091 free_conf(conf);
91adb564
N		 7092 return ERR_PTR(-EIO);
7093 } else
7094 return ERR_PTR(-ENOMEM);
7095}
7096
c148ffdc
N		 7097static int only_parity(int raid_disk, int algo, int raid_disks, int max_degraded)
7098{
7099 switch (algo) {
7100 case ALGORITHM_PARITY_0:
7101 if (raid_disk < max_degraded)
7102 return 1;
7103 break;
7104 case ALGORITHM_PARITY_N:
7105 if (raid_disk >= raid_disks - max_degraded)
7106 return 1;
7107 break;
7108 case ALGORITHM_PARITY_0_6:
f72ffdd6 7109 if (raid_disk == 0 ||
c148ffdc
N		 7110 raid_disk == raid_disks - 1)
7111 return 1;
7112 break;
7113 case ALGORITHM_LEFT_ASYMMETRIC_6:
7114 case ALGORITHM_RIGHT_ASYMMETRIC_6:
7115 case ALGORITHM_LEFT_SYMMETRIC_6:
7116 case ALGORITHM_RIGHT_SYMMETRIC_6:
7117 if (raid_disk == raid_disks - 1)
7118 return 1;
7119 }
7120 return 0;
7121}
7122
849674e4 7123static int raid5_run(struct mddev *mddev)
91adb564 7124{
d1688a6d 7125 struct r5conf *conf;
9f7c2220 7126 int working_disks = 0;
c148ffdc 7127 int dirty_parity_disks = 0;
3cb03002 7128 struct md_rdev *rdev;
713cf5a6 7129 struct md_rdev *journal_dev = NULL;
c148ffdc 7130 sector_t reshape_offset = 0;
17045f52 7131 int i;
b5254dd5
N		 7132 long long min_offset_diff = 0;
7133 int first = 1;
91adb564 7134
a415c0f1
N		 7135 if (mddev_init_writes_pending(mddev) < 0)
7136 return -ENOMEM;
7137
8c6ac868 7138 if (mddev->recovery_cp != MaxSector)
cc6167b4
N		 7139 pr_notice("md/raid:%s: not clean -- starting background reconstruction\n",
7140 mdname(mddev));
b5254dd5
N		 7141
7142 rdev_for_each(rdev, mddev) {
7143 long long diff;
713cf5a6 7144
f2076e7d 7145 if (test_bit(Journal, &rdev->flags)) {
713cf5a6 7146 journal_dev = rdev;
f2076e7d
SL		 7147 continue;
7148 }
b5254dd5
N		 7149 if (rdev->raid_disk < 0)
7150 continue;
7151 diff = (rdev->new_data_offset - rdev->data_offset);
7152 if (first) {
7153 min_offset_diff = diff;
7154 first = 0;
7155 } else if (mddev->reshape_backwards &&
7156 diff < min_offset_diff)
7157 min_offset_diff = diff;
7158 else if (!mddev->reshape_backwards &&
7159 diff > min_offset_diff)
7160 min_offset_diff = diff;
7161 }
7162
230b55fa
N		 7163 if ((test_bit(MD_HAS_JOURNAL, &mddev->flags) || journal_dev) &&
7164 (mddev->bitmap_info.offset || mddev->bitmap_info.file)) {
7165 pr_notice("md/raid:%s: array cannot have both journal and bitmap\n",
7166 mdname(mddev));
7167 return -EINVAL;
7168 }
7169
91adb564
N		 7170 if (mddev->reshape_position != MaxSector) {
7171 /* Check that we can continue the reshape.
b5254dd5
N		 7172 * Difficulties arise if the stripe we would write to
7173 * next is at or after the stripe we would read from next.
7174 * For a reshape that changes the number of devices, this
7175 * is only possible for a very short time, and mdadm makes
7176 * sure that time appears to have past before assembling
7177 * the array. So we fail if that time hasn't passed.
7178 * For a reshape that keeps the number of devices the same
7179 * mdadm must be monitoring the reshape can keeping the
7180 * critical areas read-only and backed up. It will start
7181 * the array in read-only mode, so we check for that.
91adb564
N		 7182 */
7183 sector_t here_new, here_old;
7184 int old_disks;
18b00334 7185 int max_degraded = (mddev->level == 6 ? 2 : 1);
05256d98
N		 7186 int chunk_sectors;
7187 int new_data_disks;
91adb564 7188
713cf5a6 7189 if (journal_dev) {
cc6167b4
N		 7190 pr_warn("md/raid:%s: don't support reshape with journal - aborting.\n",
7191 mdname(mddev));
713cf5a6
SL		 7192 return -EINVAL;
7193 }
7194
88ce4930 7195 if (mddev->new_level != mddev->level) {
cc6167b4
N		 7196 pr_warn("md/raid:%s: unsupported reshape required - aborting.\n",
7197 mdname(mddev));
91adb564
N		 7198 return -EINVAL;
7199 }
91adb564
N		 7200 old_disks = mddev->raid_disks - mddev->delta_disks;
7201 /* reshape_position must be on a new-stripe boundary, and one
7202 * further up in new geometry must map after here in old
7203 * geometry.
05256d98
N		 7204 * If the chunk sizes are different, then as we perform reshape
7205 * in units of the largest of the two, reshape_position needs
7206 * be a multiple of the largest chunk size times new data disks.
91adb564
N		 7207 */
7208 here_new = mddev->reshape_position;
05256d98
N		 7209 chunk_sectors = max(mddev->chunk_sectors, mddev->new_chunk_sectors);
7210 new_data_disks = mddev->raid_disks - max_degraded;
7211 if (sector_div(here_new, chunk_sectors * new_data_disks)) {
cc6167b4
N		 7212 pr_warn("md/raid:%s: reshape_position not on a stripe boundary\n",
7213 mdname(mddev));
91adb564
N		 7214 return -EINVAL;
7215 }
05256d98 7216 reshape_offset = here_new * chunk_sectors;
91adb564
N		 7217 /* here_new is the stripe we will write to */
7218 here_old = mddev->reshape_position;
05256d98 7219 sector_div(here_old, chunk_sectors * (old_disks-max_degraded));
91adb564
N		 7220 /* here_old is the first stripe that we might need to read
7221 * from */
67ac6011
N		 7222 if (mddev->delta_disks == 0) {
7223 /* We cannot be sure it is safe to start an in-place
b5254dd5 7224 * reshape. It is only safe if user-space is monitoring
67ac6011
N		 7225 * and taking constant backups.
7226 * mdadm always starts a situation like this in
7227 * readonly mode so it can take control before
7228 * allowing any writes. So just check for that.
7229 */
b5254dd5
N		 7230 if (abs(min_offset_diff) >= mddev->chunk_sectors &&
7231 abs(min_offset_diff) >= mddev->new_chunk_sectors)
7232 /* not really in-place - so OK */;
7233 else if (mddev->ro == 0) {
cc6167b4
N		 7234 pr_warn("md/raid:%s: in-place reshape must be started in read-only mode - aborting\n",
7235 mdname(mddev));
67ac6011
N		 7236 return -EINVAL;
7237 }
2c810cdd 7238 } else if (mddev->reshape_backwards
05256d98
N		 7239 ? (here_new * chunk_sectors + min_offset_diff <=
7240 here_old * chunk_sectors)
7241 : (here_new * chunk_sectors >=
7242 here_old * chunk_sectors + (-min_offset_diff))) {
91adb564 7243 /* Reading from the same stripe as writing to - bad */
cc6167b4
N		 7244 pr_warn("md/raid:%s: reshape_position too early for auto-recovery - aborting.\n",
7245 mdname(mddev));
91adb564
N		 7246 return -EINVAL;
7247 }
cc6167b4 7248 pr_debug("md/raid:%s: reshape will continue\n", mdname(mddev));
91adb564
N		 7249 /* OK, we should be able to continue; */
7250 } else {
7251 BUG_ON(mddev->level != mddev->new_level);
7252 BUG_ON(mddev->layout != mddev->new_layout);
664e7c41 7253 BUG_ON(mddev->chunk_sectors != mddev->new_chunk_sectors);
91adb564 7254 BUG_ON(mddev->delta_disks != 0);
1da177e4 7255 }
91adb564 7256
3418d036
AP		 7257 if (test_bit(MD_HAS_JOURNAL, &mddev->flags) &&
7258 test_bit(MD_HAS_PPL, &mddev->flags)) {
7259 pr_warn("md/raid:%s: using journal device and PPL not allowed - disabling PPL\n",
7260 mdname(mddev));
7261 clear_bit(MD_HAS_PPL, &mddev->flags);
ddc08823 7262 clear_bit(MD_HAS_MULTIPLE_PPLS, &mddev->flags);
3418d036
AP		 7263 }
7264
245f46c2
N		 7265 if (mddev->private == NULL)
7266 conf = setup_conf(mddev);
7267 else
7268 conf = mddev->private;
7269
91adb564
N		 7270 if (IS_ERR(conf))
7271 return PTR_ERR(conf);
7272
486b0f7b
SL		 7273 if (test_bit(MD_HAS_JOURNAL, &mddev->flags)) {
7274 if (!journal_dev) {
cc6167b4
N		 7275 pr_warn("md/raid:%s: journal disk is missing, force array readonly\n",
7276 mdname(mddev));
486b0f7b
SL		 7277 mddev->ro = 1;
7278 set_disk_ro(mddev->gendisk, 1);
7279 } else if (mddev->recovery_cp == MaxSector)
7280 set_bit(MD_JOURNAL_CLEAN, &mddev->flags);
7dde2ad3
SL		 7281 }
7282
b5254dd5 7283 conf->min_offset_diff = min_offset_diff;
91adb564
N		 7284 mddev->thread = conf->thread;
7285 conf->thread = NULL;
7286 mddev->private = conf;
7287
17045f52
N		 7288 for (i = 0; i < conf->raid_disks && conf->previous_raid_disks;
7289 i++) {
7290 rdev = conf->disks[i].rdev;
7291 if (!rdev && conf->disks[i].replacement) {
7292 /* The replacement is all we have yet */
7293 rdev = conf->disks[i].replacement;
7294 conf->disks[i].replacement = NULL;
7295 clear_bit(Replacement, &rdev->flags);
7296 conf->disks[i].rdev = rdev;
7297 }
7298 if (!rdev)
c148ffdc 7299 continue;
17045f52
N		 7300 if (conf->disks[i].replacement &&
7301 conf->reshape_progress != MaxSector) {
7302 /* replacements and reshape simply do not mix. */
cc6167b4 7303 pr_warn("md: cannot handle concurrent replacement and reshape.\n");
17045f52
N		 7304 goto abort;
7305 }
2f115882 7306 if (test_bit(In_sync, &rdev->flags)) {
91adb564 7307 working_disks++;
2f115882
N		 7308 continue;
7309 }
c148ffdc
N		 7310 /* This disc is not fully in-sync. However if it
7311 * just stored parity (beyond the recovery_offset),
7312 * when we don't need to be concerned about the
7313 * array being dirty.
7314 * When reshape goes 'backwards', we never have
7315 * partially completed devices, so we only need
7316 * to worry about reshape going forwards.
7317 */
7318 /* Hack because v0.91 doesn't store recovery_offset properly. */
7319 if (mddev->major_version == 0 &&
7320 mddev->minor_version > 90)
7321 rdev->recovery_offset = reshape_offset;
5026d7a9 7322
c148ffdc
N		 7323 if (rdev->recovery_offset < reshape_offset) {
7324 /* We need to check old and new layout */
7325 if (!only_parity(rdev->raid_disk,
7326 conf->algorithm,
7327 conf->raid_disks,
7328 conf->max_degraded))
7329 continue;
7330 }
7331 if (!only_parity(rdev->raid_disk,
7332 conf->prev_algo,
7333 conf->previous_raid_disks,
7334 conf->max_degraded))
7335 continue;
7336 dirty_parity_disks++;
7337 }
91adb564 7338
17045f52
N		 7339 /*
7340 * 0 for a fully functional array, 1 or 2 for a degraded array.
7341 */
2e38a37f 7342 mddev->degraded = raid5_calc_degraded(conf);
91adb564 7343
674806d6 7344 if (has_failed(conf)) {
cc6167b4 7345 pr_crit("md/raid:%s: not enough operational devices (%d/%d failed)\n",
02c2de8c 7346 mdname(mddev), mddev->degraded, conf->raid_disks);
1da177e4
LT		 7347 goto abort;
7348 }
7349
91adb564 7350 /* device size must be a multiple of chunk size */
9d8f0363 7351 mddev->dev_sectors &= ~(mddev->chunk_sectors - 1);
91adb564
N		 7352 mddev->resync_max_sectors = mddev->dev_sectors;
7353
c148ffdc 7354 if (mddev->degraded > dirty_parity_disks &&
1da177e4 7355 mddev->recovery_cp != MaxSector) {
4536bf9b
AP		 7356 if (test_bit(MD_HAS_PPL, &mddev->flags))
7357 pr_crit("md/raid:%s: starting dirty degraded array with PPL.\n",
7358 mdname(mddev));
7359 else if (mddev->ok_start_degraded)
cc6167b4
N		 7360 pr_crit("md/raid:%s: starting dirty degraded array - data corruption possible.\n",
7361 mdname(mddev));
6ff8d8ec 7362 else {
cc6167b4
N		 7363 pr_crit("md/raid:%s: cannot start dirty degraded array.\n",
7364 mdname(mddev));
6ff8d8ec
N		 7365 goto abort;
7366 }
1da177e4
LT		 7367 }
7368
cc6167b4
N		 7369 pr_info("md/raid:%s: raid level %d active with %d out of %d devices, algorithm %d\n",
7370 mdname(mddev), conf->level,
7371 mddev->raid_disks-mddev->degraded, mddev->raid_disks,
7372 mddev->new_layout);
1da177e4
LT		 7373
7374 print_raid5_conf(conf);
7375
fef9c61f 7376 if (conf->reshape_progress != MaxSector) {
fef9c61f 7377 conf->reshape_safe = conf->reshape_progress;
f6705578
N		 7378 atomic_set(&conf->reshape_stripes, 0);
7379 clear_bit(MD_RECOVERY_SYNC, &mddev->recovery);
7380 clear_bit(MD_RECOVERY_CHECK, &mddev->recovery);
7381 set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery);
7382 set_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
7383 mddev->sync_thread = md_register_thread(md_do_sync, mddev,
0da3c619 7384 "reshape");
f6705578
N		 7385 }
7386
1da177e4 7387 /* Ok, everything is just fine now */
a64c876f
N		 7388 if (mddev->to_remove == &raid5_attrs_group)
7389 mddev->to_remove = NULL;
00bcb4ac
N		 7390 else if (mddev->kobj.sd &&
7391 sysfs_create_group(&mddev->kobj, &raid5_attrs_group))
cc6167b4
N		 7392 pr_warn("raid5: failed to create sysfs attributes for %s\n",
7393 mdname(mddev));
4a5add49 7394 md_set_array_sectors(mddev, raid5_size(mddev, 0, 0));
7a5febe9 7395
4a5add49 7396 if (mddev->queue) {
9f7c2220 7397 int chunk_size;
4a5add49
N		 7398 /* read-ahead size must cover two whole stripes, which
7399 * is 2 * (datadisks) * chunksize where 'n' is the
7400 * number of raid devices
7401 */
7402 int data_disks = conf->previous_raid_disks - conf->max_degraded;
7403 int stripe = data_disks *
7404 ((mddev->chunk_sectors << 9) / PAGE_SIZE);
dc3b17cc
JK		 7405 if (mddev->queue->backing_dev_info->ra_pages < 2 * stripe)
7406 mddev->queue->backing_dev_info->ra_pages = 2 * stripe;
91adb564 7407
9f7c2220
N		 7408 chunk_size = mddev->chunk_sectors << 9;
7409 blk_queue_io_min(mddev->queue, chunk_size);
7410 blk_queue_io_opt(mddev->queue, chunk_size *
7411 (conf->raid_disks - conf->max_degraded));
c78afc62 7412 mddev->queue->limits.raid_partial_stripes_expensive = 1;
620125f2
SL		 7413 /*
7414 * We can only discard a whole stripe. It doesn't make sense to
7415 * discard data disk but write parity disk
7416 */
7417 stripe = stripe * PAGE_SIZE;
4ac6875e
N		 7418 /* Round up to power of 2, as discard handling
7419 * currently assumes that */
7420 while ((stripe-1) & stripe)
7421 stripe = (stripe | (stripe-1)) + 1;
620125f2
SL		 7422 mddev->queue->limits.discard_alignment = stripe;
7423 mddev->queue->limits.discard_granularity = stripe;
e8d7c332 7424
5026d7a9 7425 blk_queue_max_write_same_sectors(mddev->queue, 0);
3deff1a7 7426 blk_queue_max_write_zeroes_sectors(mddev->queue, 0);
5026d7a9 7427
05616be5 7428 rdev_for_each(rdev, mddev) {
9f7c2220
N		 7429 disk_stack_limits(mddev->gendisk, rdev->bdev,
7430 rdev->data_offset << 9);
05616be5
N		 7431 disk_stack_limits(mddev->gendisk, rdev->bdev,
7432 rdev->new_data_offset << 9);
7433 }
620125f2 7434
48920ff2
CH		 7435 /*
7436 * zeroing is required, otherwise data
7437 * could be lost. Consider a scenario: discard a stripe
7438 * (the stripe could be inconsistent if
7439 * discard_zeroes_data is 0); write one disk of the
7440 * stripe (the stripe could be inconsistent again
7441 * depending on which disks are used to calculate
7442 * parity); the disk is broken; The stripe data of this
7443 * disk is lost.
7444 *
7445 * We only allow DISCARD if the sysadmin has confirmed that
7446 * only safe devices are in use by setting a module parameter.
7447 * A better idea might be to turn DISCARD into WRITE_ZEROES
7448 * requests, as that is required to be safe.
7449 */
7450 if (devices_handle_discard_safely &&
e7597e69
JS		 7451 mddev->queue->limits.max_discard_sectors >= (stripe >> 9) &&
7452 mddev->queue->limits.discard_granularity >= stripe)
8b904b5b 7453 blk_queue_flag_set(QUEUE_FLAG_DISCARD,
620125f2
SL		 7454 mddev->queue);
7455 else
8b904b5b 7456 blk_queue_flag_clear(QUEUE_FLAG_DISCARD,
620125f2 7457 mddev->queue);
1dffdddd
SL		 7458
7459 blk_queue_max_hw_sectors(mddev->queue, UINT_MAX);
9f7c2220 7460 }
23032a0e 7461
845b9e22 7462 if (log_init(conf, journal_dev, raid5_has_ppl(conf)))
ff875738 7463 goto abort;
5c7e81c3 7464
1da177e4
LT		 7465 return 0;
7466abort:
01f96c0a 7467 md_unregister_thread(&mddev->thread);
e4f869d9
N		 7468 print_raid5_conf(conf);
7469 free_conf(conf);
1da177e4 7470 mddev->private = NULL;
cc6167b4 7471 pr_warn("md/raid:%s: failed to run raid set.\n", mdname(mddev));
1da177e4
LT		 7472 return -EIO;
7473}
7474
afa0f557 7475static void raid5_free(struct mddev *mddev, void *priv)
1da177e4 7476{
afa0f557 7477 struct r5conf *conf = priv;
1da177e4 7478
95fc17aa 7479 free_conf(conf);
a64c876f 7480 mddev->to_remove = &raid5_attrs_group;
1da177e4
LT		 7481}
7482
849674e4 7483static void raid5_status(struct seq_file *seq, struct mddev *mddev)
1da177e4 7484{
d1688a6d 7485 struct r5conf *conf = mddev->private;
1da177e4
LT		 7486 int i;
7487
9d8f0363 7488 seq_printf(seq, " level %d, %dk chunk, algorithm %d", mddev->level,
3cb5edf4 7489 conf->chunk_sectors / 2, mddev->layout);
02c2de8c 7490 seq_printf (seq, " [%d/%d] [", conf->raid_disks, conf->raid_disks - mddev->degraded);
5fd13351
N		 7491 rcu_read_lock();
7492 for (i = 0; i < conf->raid_disks; i++) {
7493 struct md_rdev *rdev = rcu_dereference(conf->disks[i].rdev);
7494 seq_printf (seq, "%s", rdev && test_bit(In_sync, &rdev->flags) ? "U" : "_");
7495 }
7496 rcu_read_unlock();
1da177e4 7497 seq_printf (seq, "]");
1da177e4
LT		 7498}
7499
d1688a6d 7500static void print_raid5_conf (struct r5conf *conf)
1da177e4
LT		 7501{
7502 int i;
7503 struct disk_info *tmp;
7504
cc6167b4 7505 pr_debug("RAID conf printout:\n");
1da177e4 7506 if (!conf) {
cc6167b4 7507 pr_debug("(conf==NULL)\n");
1da177e4
LT		 7508 return;
7509 }
cc6167b4 7510 pr_debug(" --- level:%d rd:%d wd:%d\n", conf->level,
0c55e022
N		 7511 conf->raid_disks,
7512 conf->raid_disks - conf->mddev->degraded);
1da177e4
LT		 7513
7514 for (i = 0; i < conf->raid_disks; i++) {
7515 char b[BDEVNAME_SIZE];
7516 tmp = conf->disks + i;
7517 if (tmp->rdev)
cc6167b4 7518 pr_debug(" disk %d, o:%d, dev:%s\n",
0c55e022
N		 7519 i, !test_bit(Faulty, &tmp->rdev->flags),
7520 bdevname(tmp->rdev->bdev, b));
1da177e4
LT		 7521 }
7522}
7523
fd01b88c 7524static int raid5_spare_active(struct mddev *mddev)
1da177e4
LT		 7525{
7526 int i;
d1688a6d 7527 struct r5conf *conf = mddev->private;
1da177e4 7528 struct disk_info *tmp;
6b965620
N		 7529 int count = 0;
7530 unsigned long flags;
1da177e4
LT		 7531
7532 for (i = 0; i < conf->raid_disks; i++) {
7533 tmp = conf->disks + i;
dd054fce
N		 7534 if (tmp->replacement
7535 && tmp->replacement->recovery_offset == MaxSector
7536 && !test_bit(Faulty, &tmp->replacement->flags)
7537 && !test_and_set_bit(In_sync, &tmp->replacement->flags)) {
7538 /* Replacement has just become active. */
7539 if (!tmp->rdev
7540 || !test_and_clear_bit(In_sync, &tmp->rdev->flags))
7541 count++;
7542 if (tmp->rdev) {
7543 /* Replaced device not technically faulty,
7544 * but we need to be sure it gets removed
7545 * and never re-added.
7546 */
7547 set_bit(Faulty, &tmp->rdev->flags);
7548 sysfs_notify_dirent_safe(
7549 tmp->rdev->sysfs_state);
7550 }
7551 sysfs_notify_dirent_safe(tmp->replacement->sysfs_state);
7552 } else if (tmp->rdev
70fffd0b 7553 && tmp->rdev->recovery_offset == MaxSector
b2d444d7 7554 && !test_bit(Faulty, &tmp->rdev->flags)
c04be0aa 7555 && !test_and_set_bit(In_sync, &tmp->rdev->flags)) {
6b965620 7556 count++;
43c73ca4 7557 sysfs_notify_dirent_safe(tmp->rdev->sysfs_state);
1da177e4
LT		 7558 }
7559 }
6b965620 7560 spin_lock_irqsave(&conf->device_lock, flags);
2e38a37f 7561 mddev->degraded = raid5_calc_degraded(conf);
6b965620 7562 spin_unlock_irqrestore(&conf->device_lock, flags);
1da177e4 7563 print_raid5_conf(conf);
6b965620 7564 return count;
1da177e4
LT		 7565}
7566
b8321b68 7567static int raid5_remove_disk(struct mddev *mddev, struct md_rdev *rdev)
1da177e4 7568{
d1688a6d 7569 struct r5conf *conf = mddev->private;
1da177e4 7570 int err = 0;
b8321b68 7571 int number = rdev->raid_disk;
657e3e4d 7572 struct md_rdev **rdevp;
1da177e4
LT		 7573 struct disk_info *p = conf->disks + number;
7574
7575 print_raid5_conf(conf);
f6b6ec5c 7576 if (test_bit(Journal, &rdev->flags) && conf->log) {
c2bb6242 7577 /*
f6b6ec5c
SL		 7578 * we can't wait pending write here, as this is called in
7579 * raid5d, wait will deadlock.
84dd97a6
N		 7580 * neilb: there is no locking about new writes here,
7581 * so this cannot be safe.
c2bb6242 7582 */
70d466f7
SL		 7583 if (atomic_read(&conf->active_stripes) ||
7584 atomic_read(&conf->r5c_cached_full_stripes) ||
7585 atomic_read(&conf->r5c_cached_partial_stripes)) {
f6b6ec5c 7586 return -EBUSY;
84dd97a6 7587 }
ff875738 7588 log_exit(conf);
f6b6ec5c 7589 return 0;
c2bb6242 7590 }
657e3e4d
N		 7591 if (rdev == p->rdev)
7592 rdevp = &p->rdev;
7593 else if (rdev == p->replacement)
7594 rdevp = &p->replacement;
7595 else
7596 return 0;
7597
7598 if (number >= conf->raid_disks &&
7599 conf->reshape_progress == MaxSector)
7600 clear_bit(In_sync, &rdev->flags);
7601
7602 if (test_bit(In_sync, &rdev->flags) ||
7603 atomic_read(&rdev->nr_pending)) {
7604 err = -EBUSY;
7605 goto abort;
7606 }
7607 /* Only remove non-faulty devices if recovery
7608 * isn't possible.
7609 */
7610 if (!test_bit(Faulty, &rdev->flags) &&
7611 mddev->recovery_disabled != conf->recovery_disabled &&
7612 !has_failed(conf) &&
dd054fce 7613 (!p->replacement || p->replacement == rdev) &&
657e3e4d
N		 7614 number < conf->raid_disks) {
7615 err = -EBUSY;
7616 goto abort;
7617 }
7618 *rdevp = NULL;
d787be40
N		 7619 if (!test_bit(RemoveSynchronized, &rdev->flags)) {
7620 synchronize_rcu();
7621 if (atomic_read(&rdev->nr_pending)) {
7622 /* lost the race, try later */
7623 err = -EBUSY;
7624 *rdevp = rdev;
7625 }
7626 }
6358c239
AP		 7627 if (!err) {
7628 err = log_modify(conf, rdev, false);
7629 if (err)
7630 goto abort;
7631 }
d787be40 7632 if (p->replacement) {
dd054fce
N		 7633 /* We must have just cleared 'rdev' */
7634 p->rdev = p->replacement;
7635 clear_bit(Replacement, &p->replacement->flags);
7636 smp_mb(); /* Make sure other CPUs may see both as identical
7637 * but will never see neither - if they are careful
7638 */
7639 p->replacement = NULL;
6358c239
AP		 7640
7641 if (!err)
7642 err = log_modify(conf, p->rdev, true);
e5bc9c3c
GJ		 7643 }
7644
7645 clear_bit(WantReplacement, &rdev->flags);
1da177e4
LT		 7646abort:
7647
7648 print_raid5_conf(conf);
7649 return err;
7650}
7651
fd01b88c 7652static int raid5_add_disk(struct mddev *mddev, struct md_rdev *rdev)
1da177e4 7653{
d1688a6d 7654 struct r5conf *conf = mddev->private;
199050ea 7655 int err = -EEXIST;
1da177e4
LT		 7656 int disk;
7657 struct disk_info *p;
6c2fce2e
NB		 7658 int first = 0;
7659 int last = conf->raid_disks - 1;
1da177e4 7660
f6b6ec5c 7661 if (test_bit(Journal, &rdev->flags)) {
f6b6ec5c
SL		 7662 if (conf->log)
7663 return -EBUSY;
7664
7665 rdev->raid_disk = 0;
7666 /*
7667 * The array is in readonly mode if journal is missing, so no
7668 * write requests running. We should be safe
7669 */
845b9e22 7670 log_init(conf, rdev, false);
f6b6ec5c
SL		 7671 return 0;
7672 }
7f0da59b
N		 7673 if (mddev->recovery_disabled == conf->recovery_disabled)
7674 return -EBUSY;
7675
dc10c643 7676 if (rdev->saved_raid_disk < 0 && has_failed(conf))
1da177e4 7677 /* no point adding a device */
199050ea 7678 return -EINVAL;
1da177e4 7679
6c2fce2e
NB		 7680 if (rdev->raid_disk >= 0)
7681 first = last = rdev->raid_disk;
1da177e4
LT		 7682
7683 /*
16a53ecc
N		 7684 * find the disk ... but prefer rdev->saved_raid_disk
7685 * if possible.
1da177e4 7686 */
16a53ecc 7687 if (rdev->saved_raid_disk >= 0 &&
6c2fce2e 7688 rdev->saved_raid_disk >= first &&
16a53ecc 7689 conf->disks[rdev->saved_raid_disk].rdev == NULL)
5cfb22a1
N		 7690 first = rdev->saved_raid_disk;
7691
7692 for (disk = first; disk <= last; disk++) {
7bfec5f3
N		 7693 p = conf->disks + disk;
7694 if (p->rdev == NULL) {
b2d444d7 7695 clear_bit(In_sync, &rdev->flags);
1da177e4 7696 rdev->raid_disk = disk;
72626685
N		 7697 if (rdev->saved_raid_disk != disk)
7698 conf->fullsync = 1;
d6065f7b 7699 rcu_assign_pointer(p->rdev, rdev);
6358c239
AP		 7700
7701 err = log_modify(conf, rdev, true);
7702
5cfb22a1 7703 goto out;
1da177e4 7704 }
5cfb22a1
N		 7705 }
7706 for (disk = first; disk <= last; disk++) {
7707 p = conf->disks + disk;
7bfec5f3
N		 7708 if (test_bit(WantReplacement, &p->rdev->flags) &&
7709 p->replacement == NULL) {
7710 clear_bit(In_sync, &rdev->flags);
7711 set_bit(Replacement, &rdev->flags);
7712 rdev->raid_disk = disk;
7713 err = 0;
7714 conf->fullsync = 1;
7715 rcu_assign_pointer(p->replacement, rdev);
7716 break;
7717 }
7718 }
5cfb22a1 7719out:
1da177e4 7720 print_raid5_conf(conf);
199050ea 7721 return err;
1da177e4
LT		 7722}
7723
fd01b88c 7724static int raid5_resize(struct mddev *mddev, sector_t sectors)
1da177e4
LT		 7725{
7726 /* no resync is happening, and there is enough space
7727 * on all devices, so we can resize.
7728 * We need to make sure resync covers any new space.
7729 * If the array is shrinking we should possibly wait until
7730 * any io in the removed space completes, but it hardly seems
7731 * worth it.
7732 */
a4a6125a 7733 sector_t newsize;
3cb5edf4
N		 7734 struct r5conf *conf = mddev->private;
7735
3418d036 7736 if (conf->log || raid5_has_ppl(conf))
713cf5a6 7737 return -EINVAL;
3cb5edf4 7738 sectors &= ~((sector_t)conf->chunk_sectors - 1);
a4a6125a
N		 7739 newsize = raid5_size(mddev, sectors, mddev->raid_disks);
7740 if (mddev->external_size &&
7741 mddev->array_sectors > newsize)
b522adcd 7742 return -EINVAL;
a4a6125a
N		 7743 if (mddev->bitmap) {
7744 int ret = bitmap_resize(mddev->bitmap, sectors, 0, 0);
7745 if (ret)
7746 return ret;
7747 }
7748 md_set_array_sectors(mddev, newsize);
b098636c
N		 7749 if (sectors > mddev->dev_sectors &&
7750 mddev->recovery_cp > mddev->dev_sectors) {
58c0fed4 7751 mddev->recovery_cp = mddev->dev_sectors;
1da177e4
LT		 7752 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
7753 }
58c0fed4 7754 mddev->dev_sectors = sectors;
4b5c7ae8 7755 mddev->resync_max_sectors = sectors;
1da177e4
LT		 7756 return 0;
7757}
7758
fd01b88c 7759static int check_stripe_cache(struct mddev *mddev)
01ee22b4
N		 7760{
7761 /* Can only proceed if there are plenty of stripe_heads.
7762 * We need a minimum of one full stripe,, and for sensible progress
7763 * it is best to have about 4 times that.
7764 * If we require 4 times, then the default 256 4K stripe_heads will
7765 * allow for chunk sizes up to 256K, which is probably OK.
7766 * If the chunk size is greater, user-space should request more
7767 * stripe_heads first.
7768 */
d1688a6d 7769 struct r5conf *conf = mddev->private;
01ee22b4 7770 if (((mddev->chunk_sectors << 9) / STRIPE_SIZE) * 4
edbe83ab 7771 > conf->min_nr_stripes ||
01ee22b4 7772 ((mddev->new_chunk_sectors << 9) / STRIPE_SIZE) * 4
edbe83ab 7773 > conf->min_nr_stripes) {
cc6167b4
N		 7774 pr_warn("md/raid:%s: reshape: not enough stripes. Needed %lu\n",
7775 mdname(mddev),
7776 ((max(mddev->chunk_sectors, mddev->new_chunk_sectors) << 9)
7777 / STRIPE_SIZE)*4);
01ee22b4
N		 7778 return 0;
7779 }
7780 return 1;
7781}
7782
fd01b88c 7783static int check_reshape(struct mddev *mddev)
29269553 7784{
d1688a6d 7785 struct r5conf *conf = mddev->private;
29269553 7786
3418d036 7787 if (conf->log || raid5_has_ppl(conf))
713cf5a6 7788 return -EINVAL;
88ce4930
N		 7789 if (mddev->delta_disks == 0 &&
7790 mddev->new_layout == mddev->layout &&
664e7c41 7791 mddev->new_chunk_sectors == mddev->chunk_sectors)
50ac168a 7792 return 0; /* nothing to do */
674806d6 7793 if (has_failed(conf))
ec32a2bd 7794 return -EINVAL;
fdcfbbb6 7795 if (mddev->delta_disks < 0 && mddev->reshape_position == MaxSector) {
ec32a2bd
N		 7796 /* We might be able to shrink, but the devices must
7797 * be made bigger first.
7798 * For raid6, 4 is the minimum size.
7799 * Otherwise 2 is the minimum
7800 */
7801 int min = 2;
7802 if (mddev->level == 6)
7803 min = 4;
7804 if (mddev->raid_disks + mddev->delta_disks < min)
7805 return -EINVAL;
7806 }
29269553 7807
01ee22b4 7808 if (!check_stripe_cache(mddev))
29269553 7809 return -ENOSPC;
29269553 7810
738a2738
N		 7811 if (mddev->new_chunk_sectors > mddev->chunk_sectors ||
7812 mddev->delta_disks > 0)
7813 if (resize_chunks(conf,
7814 conf->previous_raid_disks
7815 + max(0, mddev->delta_disks),
7816 max(mddev->new_chunk_sectors,
7817 mddev->chunk_sectors)
7818 ) < 0)
7819 return -ENOMEM;
845b9e22
AP		 7820
7821 if (conf->previous_raid_disks + mddev->delta_disks <= conf->pool_size)
7822 return 0; /* never bother to shrink */
e56108d6
N		 7823 return resize_stripes(conf, (conf->previous_raid_disks
7824 + mddev->delta_disks));
63c70c4f
N		 7825}
7826
fd01b88c 7827static int raid5_start_reshape(struct mddev *mddev)
63c70c4f 7828{
d1688a6d 7829 struct r5conf *conf = mddev->private;
3cb03002 7830 struct md_rdev *rdev;
63c70c4f 7831 int spares = 0;
c04be0aa 7832 unsigned long flags;
63c70c4f 7833
f416885e 7834 if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
63c70c4f
N		 7835 return -EBUSY;
7836
01ee22b4
N		 7837 if (!check_stripe_cache(mddev))
7838 return -ENOSPC;
7839
30b67645
N		 7840 if (has_failed(conf))
7841 return -EINVAL;
7842
c6563a8c 7843 rdev_for_each(rdev, mddev) {
469518a3
N		 7844 if (!test_bit(In_sync, &rdev->flags)
7845 && !test_bit(Faulty, &rdev->flags))
29269553 7846 spares++;
c6563a8c 7847 }
63c70c4f 7848
f416885e 7849 if (spares - mddev->degraded < mddev->delta_disks - conf->max_degraded)
29269553
N		 7850 /* Not enough devices even to make a degraded array
7851 * of that size
7852 */
7853 return -EINVAL;
7854
ec32a2bd
N		 7855 /* Refuse to reduce size of the array. Any reductions in
7856 * array size must be through explicit setting of array_size
7857 * attribute.
7858 */
7859 if (raid5_size(mddev, 0, conf->raid_disks + mddev->delta_disks)
7860 < mddev->array_sectors) {
cc6167b4
N		 7861 pr_warn("md/raid:%s: array size must be reduced before number of disks\n",
7862 mdname(mddev));
ec32a2bd
N		 7863 return -EINVAL;
7864 }
7865
f6705578 7866 atomic_set(&conf->reshape_stripes, 0);
29269553 7867 spin_lock_irq(&conf->device_lock);
c46501b2 7868 write_seqcount_begin(&conf->gen_lock);
29269553 7869 conf->previous_raid_disks = conf->raid_disks;
63c70c4f 7870 conf->raid_disks += mddev->delta_disks;
09c9e5fa
AN		 7871 conf->prev_chunk_sectors = conf->chunk_sectors;
7872 conf->chunk_sectors = mddev->new_chunk_sectors;
88ce4930
N		 7873 conf->prev_algo = conf->algorithm;
7874 conf->algorithm = mddev->new_layout;
05616be5
N		 7875 conf->generation++;
7876 /* Code that selects data_offset needs to see the generation update
7877 * if reshape_progress has been set - so a memory barrier needed.
7878 */
7879 smp_mb();
2c810cdd 7880 if (mddev->reshape_backwards)
fef9c61f
N		 7881 conf->reshape_progress = raid5_size(mddev, 0, 0);
7882 else
7883 conf->reshape_progress = 0;
7884 conf->reshape_safe = conf->reshape_progress;
c46501b2 7885 write_seqcount_end(&conf->gen_lock);
29269553
N		 7886 spin_unlock_irq(&conf->device_lock);
7887
4d77e3ba
N		 7888 /* Now make sure any requests that proceeded on the assumption
7889 * the reshape wasn't running - like Discard or Read - have
7890 * completed.
7891 */
7892 mddev_suspend(mddev);
7893 mddev_resume(mddev);
7894
29269553
N		 7895 /* Add some new drives, as many as will fit.
7896 * We know there are enough to make the newly sized array work.
3424bf6a
N		 7897 * Don't add devices if we are reducing the number of
7898 * devices in the array. This is because it is not possible
7899 * to correctly record the "partially reconstructed" state of
7900 * such devices during the reshape and confusion could result.
29269553 7901 */
87a8dec9 7902 if (mddev->delta_disks >= 0) {
dafb20fa 7903 rdev_for_each(rdev, mddev)
87a8dec9
N		 7904 if (rdev->raid_disk < 0 &&
7905 !test_bit(Faulty, &rdev->flags)) {
7906 if (raid5_add_disk(mddev, rdev) == 0) {
87a8dec9 7907 if (rdev->raid_disk
9d4c7d87 7908 >= conf->previous_raid_disks)
87a8dec9 7909 set_bit(In_sync, &rdev->flags);
9d4c7d87 7910 else
87a8dec9 7911 rdev->recovery_offset = 0;
36fad858
NK		 7912
7913 if (sysfs_link_rdev(mddev, rdev))
87a8dec9 7914 /* Failure here is OK */;
50da0840 7915 }
87a8dec9
N		 7916 } else if (rdev->raid_disk >= conf->previous_raid_disks
7917 && !test_bit(Faulty, &rdev->flags)) {
7918 /* This is a spare that was manually added */
7919 set_bit(In_sync, &rdev->flags);
87a8dec9 7920 }
29269553 7921
87a8dec9
N		 7922 /* When a reshape changes the number of devices,
7923 * ->degraded is measured against the larger of the
7924 * pre and post number of devices.
7925 */
ec32a2bd 7926 spin_lock_irqsave(&conf->device_lock, flags);
2e38a37f 7927 mddev->degraded = raid5_calc_degraded(conf);
ec32a2bd
N		 7928 spin_unlock_irqrestore(&conf->device_lock, flags);
7929 }
63c70c4f 7930 mddev->raid_disks = conf->raid_disks;
e516402c 7931 mddev->reshape_position = conf->reshape_progress;
2953079c 7932 set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
f6705578 7933
29269553
N		 7934 clear_bit(MD_RECOVERY_SYNC, &mddev->recovery);
7935 clear_bit(MD_RECOVERY_CHECK, &mddev->recovery);
ea358cd0 7936 clear_bit(MD_RECOVERY_DONE, &mddev->recovery);
29269553
N		 7937 set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery);
7938 set_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
7939 mddev->sync_thread = md_register_thread(md_do_sync, mddev,
0da3c619 7940 "reshape");
29269553
N		 7941 if (!mddev->sync_thread) {
7942 mddev->recovery = 0;
7943 spin_lock_irq(&conf->device_lock);
ba8805b9 7944 write_seqcount_begin(&conf->gen_lock);
29269553 7945 mddev->raid_disks = conf->raid_disks = conf->previous_raid_disks;
ba8805b9
N		 7946 mddev->new_chunk_sectors =
7947 conf->chunk_sectors = conf->prev_chunk_sectors;
7948 mddev->new_layout = conf->algorithm = conf->prev_algo;
05616be5
N		 7949 rdev_for_each(rdev, mddev)
7950 rdev->new_data_offset = rdev->data_offset;
7951 smp_wmb();
ba8805b9 7952 conf->generation --;
fef9c61f 7953 conf->reshape_progress = MaxSector;
1e3fa9bd 7954 mddev->reshape_position = MaxSector;
ba8805b9 7955 write_seqcount_end(&conf->gen_lock);
29269553
N		 7956 spin_unlock_irq(&conf->device_lock);
7957 return -EAGAIN;
7958 }
c8f517c4 7959 conf->reshape_checkpoint = jiffies;
29269553
N		 7960 md_wakeup_thread(mddev->sync_thread);
7961 md_new_event(mddev);
7962 return 0;
7963}
29269553 7964
ec32a2bd
N		 7965/* This is called from the reshape thread and should make any
7966 * changes needed in 'conf'
7967 */
d1688a6d 7968static void end_reshape(struct r5conf *conf)
29269553 7969{
29269553 7970
f6705578 7971 if (!test_bit(MD_RECOVERY_INTR, &conf->mddev->recovery)) {
db0505d3 7972 struct md_rdev *rdev;
f6705578 7973
f6705578 7974 spin_lock_irq(&conf->device_lock);
cea9c228 7975 conf->previous_raid_disks = conf->raid_disks;
b5d27718 7976 md_finish_reshape(conf->mddev);
05616be5 7977 smp_wmb();
fef9c61f 7978 conf->reshape_progress = MaxSector;
6cbd8148 7979 conf->mddev->reshape_position = MaxSector;
db0505d3
N		 7980 rdev_for_each(rdev, conf->mddev)
7981 if (rdev->raid_disk >= 0 &&
7982 !test_bit(Journal, &rdev->flags) &&
7983 !test_bit(In_sync, &rdev->flags))
7984 rdev->recovery_offset = MaxSector;
f6705578 7985 spin_unlock_irq(&conf->device_lock);
b0f9ec04 7986 wake_up(&conf->wait_for_overlap);
16a53ecc
N		 7987
7988 /* read-ahead size must cover two whole stripes, which is
7989 * 2 * (datadisks) * chunksize where 'n' is the number of raid devices
7990 */
4a5add49 7991 if (conf->mddev->queue) {
cea9c228 7992 int data_disks = conf->raid_disks - conf->max_degraded;
09c9e5fa 7993 int stripe = data_disks * ((conf->chunk_sectors << 9)
cea9c228 7994 / PAGE_SIZE);
dc3b17cc
JK		 7995 if (conf->mddev->queue->backing_dev_info->ra_pages < 2 * stripe)
7996 conf->mddev->queue->backing_dev_info->ra_pages = 2 * stripe;
16a53ecc 7997 }
29269553 7998 }
29269553
N		 7999}
8000
ec32a2bd
N		 8001/* This is called from the raid5d thread with mddev_lock held.
8002 * It makes config changes to the device.
8003 */
fd01b88c 8004static void raid5_finish_reshape(struct mddev *mddev)
cea9c228 8005{
d1688a6d 8006 struct r5conf *conf = mddev->private;
cea9c228
N		 8007
8008 if (!test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
8009
8876391e 8010 if (mddev->delta_disks <= 0) {
ec32a2bd 8011 int d;
908f4fbd 8012 spin_lock_irq(&conf->device_lock);
2e38a37f 8013 mddev->degraded = raid5_calc_degraded(conf);
908f4fbd 8014 spin_unlock_irq(&conf->device_lock);
ec32a2bd
N		 8015 for (d = conf->raid_disks ;
8016 d < conf->raid_disks - mddev->delta_disks;
1a67dde0 8017 d++) {
3cb03002 8018 struct md_rdev *rdev = conf->disks[d].rdev;
da7613b8
N		 8019 if (rdev)
8020 clear_bit(In_sync, &rdev->flags);
8021 rdev = conf->disks[d].replacement;
8022 if (rdev)
8023 clear_bit(In_sync, &rdev->flags);
1a67dde0 8024 }
cea9c228 8025 }
88ce4930 8026 mddev->layout = conf->algorithm;
09c9e5fa 8027 mddev->chunk_sectors = conf->chunk_sectors;
ec32a2bd
N		 8028 mddev->reshape_position = MaxSector;
8029 mddev->delta_disks = 0;
2c810cdd 8030 mddev->reshape_backwards = 0;
cea9c228
N		 8031 }
8032}
8033
b03e0ccb 8034static void raid5_quiesce(struct mddev *mddev, int quiesce)
72626685 8035{
d1688a6d 8036 struct r5conf *conf = mddev->private;
72626685 8037
b03e0ccb
N		 8038 if (quiesce) {
8039 /* stop all writes */
566c09c5 8040 lock_all_device_hash_locks_irq(conf);
64bd660b
N		 8041 /* '2' tells resync/reshape to pause so that all
8042 * active stripes can drain
8043 */
a39f7afd 8044 r5c_flush_cache(conf, INT_MAX);
64bd660b 8045 conf->quiesce = 2;
b1b46486 8046 wait_event_cmd(conf->wait_for_quiescent,
46031f9a
RBJ		 8047 atomic_read(&conf->active_stripes) == 0 &&
8048 atomic_read(&conf->active_aligned_reads) == 0,
566c09c5
SL		 8049 unlock_all_device_hash_locks_irq(conf),
8050 lock_all_device_hash_locks_irq(conf));
64bd660b 8051 conf->quiesce = 1;
566c09c5 8052 unlock_all_device_hash_locks_irq(conf);
64bd660b
N		 8053 /* allow reshape to continue */
8054 wake_up(&conf->wait_for_overlap);
b03e0ccb
N		 8055 } else {
8056 /* re-enable writes */
566c09c5 8057 lock_all_device_hash_locks_irq(conf);
72626685 8058 conf->quiesce = 0;
b1b46486 8059 wake_up(&conf->wait_for_quiescent);
e464eafd 8060 wake_up(&conf->wait_for_overlap);
566c09c5 8061 unlock_all_device_hash_locks_irq(conf);
72626685 8062 }
1532d9e8 8063 log_quiesce(conf, quiesce);
72626685 8064}
b15c2e57 8065
fd01b88c 8066static void *raid45_takeover_raid0(struct mddev *mddev, int level)
54071b38 8067{
e373ab10 8068 struct r0conf *raid0_conf = mddev->private;
d76c8420 8069 sector_t sectors;
54071b38 8070
f1b29bca 8071 /* for raid0 takeover only one zone is supported */
e373ab10 8072 if (raid0_conf->nr_strip_zones > 1) {
cc6167b4
N		 8073 pr_warn("md/raid:%s: cannot takeover raid0 with more than one zone.\n",
8074 mdname(mddev));
f1b29bca
DW		 8075 return ERR_PTR(-EINVAL);
8076 }
8077
e373ab10
N		 8078 sectors = raid0_conf->strip_zone[0].zone_end;
8079 sector_div(sectors, raid0_conf->strip_zone[0].nb_dev);
3b71bd93 8080 mddev->dev_sectors = sectors;
f1b29bca 8081 mddev->new_level = level;
54071b38
TM		 8082 mddev->new_layout = ALGORITHM_PARITY_N;
8083 mddev->new_chunk_sectors = mddev->chunk_sectors;
8084 mddev->raid_disks += 1;
8085 mddev->delta_disks = 1;
8086 /* make sure it will be not marked as dirty */
8087 mddev->recovery_cp = MaxSector;
8088
8089 return setup_conf(mddev);
8090}
8091
fd01b88c 8092static void *raid5_takeover_raid1(struct mddev *mddev)
d562b0c4
N		 8093{
8094 int chunksect;
6995f0b2 8095 void *ret;
d562b0c4
N		 8096
8097 if (mddev->raid_disks != 2 ||
8098 mddev->degraded > 1)
8099 return ERR_PTR(-EINVAL);
8100
8101 /* Should check if there are write-behind devices? */
8102
8103 chunksect = 64*2; /* 64K by default */
8104
8105 /* The array must be an exact multiple of chunksize */
8106 while (chunksect && (mddev->array_sectors & (chunksect-1)))
8107 chunksect >>= 1;
8108
8109 if ((chunksect<<9) < STRIPE_SIZE)
8110 /* array size does not allow a suitable chunk size */
8111 return ERR_PTR(-EINVAL);
8112
8113 mddev->new_level = 5;
8114 mddev->new_layout = ALGORITHM_LEFT_SYMMETRIC;
664e7c41 8115 mddev->new_chunk_sectors = chunksect;
d562b0c4 8116
6995f0b2 8117 ret = setup_conf(mddev);
32cd7cbb 8118 if (!IS_ERR(ret))
394ed8e4
SL		 8119 mddev_clear_unsupported_flags(mddev,
8120 UNSUPPORTED_MDDEV_FLAGS);
6995f0b2 8121 return ret;
d562b0c4
N		 8122}
8123
fd01b88c 8124static void *raid5_takeover_raid6(struct mddev *mddev)
fc9739c6
N		 8125{
8126 int new_layout;
8127
8128 switch (mddev->layout) {
8129 case ALGORITHM_LEFT_ASYMMETRIC_6:
8130 new_layout = ALGORITHM_LEFT_ASYMMETRIC;
8131 break;
8132 case ALGORITHM_RIGHT_ASYMMETRIC_6:
8133 new_layout = ALGORITHM_RIGHT_ASYMMETRIC;
8134 break;
8135 case ALGORITHM_LEFT_SYMMETRIC_6:
8136 new_layout = ALGORITHM_LEFT_SYMMETRIC;
8137 break;
8138 case ALGORITHM_RIGHT_SYMMETRIC_6:
8139 new_layout = ALGORITHM_RIGHT_SYMMETRIC;
8140 break;
8141 case ALGORITHM_PARITY_0_6:
8142 new_layout = ALGORITHM_PARITY_0;
8143 break;
8144 case ALGORITHM_PARITY_N:
8145 new_layout = ALGORITHM_PARITY_N;
8146 break;
8147 default:
8148 return ERR_PTR(-EINVAL);
8149 }
8150 mddev->new_level = 5;
8151 mddev->new_layout = new_layout;
8152 mddev->delta_disks = -1;
8153 mddev->raid_disks -= 1;
8154 return setup_conf(mddev);
8155}
8156
fd01b88c 8157static int raid5_check_reshape(struct mddev *mddev)
b3546035 8158{
88ce4930
N		 8159 /* For a 2-drive array, the layout and chunk size can be changed
8160 * immediately as not restriping is needed.
8161 * For larger arrays we record the new value - after validation
8162 * to be used by a reshape pass.
b3546035 8163 */
d1688a6d 8164 struct r5conf *conf = mddev->private;
597a711b 8165 int new_chunk = mddev->new_chunk_sectors;
b3546035 8166
597a711b 8167 if (mddev->new_layout >= 0 && !algorithm_valid_raid5(mddev->new_layout))
b3546035
N		 8168 return -EINVAL;
8169 if (new_chunk > 0) {
0ba459d2 8170 if (!is_power_of_2(new_chunk))
b3546035 8171 return -EINVAL;
597a711b 8172 if (new_chunk < (PAGE_SIZE>>9))
b3546035 8173 return -EINVAL;
597a711b 8174 if (mddev->array_sectors & (new_chunk-1))
b3546035
N		 8175 /* not factor of array size */
8176 return -EINVAL;
8177 }
8178
8179 /* They look valid */
8180
88ce4930 8181 if (mddev->raid_disks == 2) {
597a711b
N		 8182 /* can make the change immediately */
8183 if (mddev->new_layout >= 0) {
8184 conf->algorithm = mddev->new_layout;
8185 mddev->layout = mddev->new_layout;
88ce4930
N		 8186 }
8187 if (new_chunk > 0) {
597a711b
N		 8188 conf->chunk_sectors = new_chunk ;
8189 mddev->chunk_sectors = new_chunk;
88ce4930 8190 }
2953079c 8191 set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
88ce4930 8192 md_wakeup_thread(mddev->thread);
b3546035 8193 }
50ac168a 8194 return check_reshape(mddev);
88ce4930
N		 8195}
8196
fd01b88c 8197static int raid6_check_reshape(struct mddev *mddev)
88ce4930 8198{
597a711b 8199 int new_chunk = mddev->new_chunk_sectors;
50ac168a 8200
597a711b 8201 if (mddev->new_layout >= 0 && !algorithm_valid_raid6(mddev->new_layout))
88ce4930 8202 return -EINVAL;
b3546035 8203 if (new_chunk > 0) {
0ba459d2 8204 if (!is_power_of_2(new_chunk))
88ce4930 8205 return -EINVAL;
597a711b 8206 if (new_chunk < (PAGE_SIZE >> 9))
88ce4930 8207 return -EINVAL;
597a711b 8208 if (mddev->array_sectors & (new_chunk-1))
88ce4930
N		 8209 /* not factor of array size */
8210 return -EINVAL;
b3546035 8211 }
88ce4930
N		 8212
8213 /* They look valid */
50ac168a 8214 return check_reshape(mddev);
b3546035
N		 8215}
8216
fd01b88c 8217static void *raid5_takeover(struct mddev *mddev)
d562b0c4
N		 8218{
8219 /* raid5 can take over:
f1b29bca 8220 * raid0 - if there is only one strip zone - make it a raid4 layout
d562b0c4
N		 8221 * raid1 - if there are two drives. We need to know the chunk size
8222 * raid4 - trivial - just use a raid4 layout.
8223 * raid6 - Providing it is a *_6 layout
d562b0c4 8224 */
f1b29bca
DW		 8225 if (mddev->level == 0)
8226 return raid45_takeover_raid0(mddev, 5);
d562b0c4
N		 8227 if (mddev->level == 1)
8228 return raid5_takeover_raid1(mddev);
e9d4758f
N		 8229 if (mddev->level == 4) {
8230 mddev->new_layout = ALGORITHM_PARITY_N;
8231 mddev->new_level = 5;
8232 return setup_conf(mddev);
8233 }
fc9739c6
N		 8234 if (mddev->level == 6)
8235 return raid5_takeover_raid6(mddev);
d562b0c4
N		 8236
8237 return ERR_PTR(-EINVAL);
8238}
8239
fd01b88c 8240static void *raid4_takeover(struct mddev *mddev)
a78d38a1 8241{
f1b29bca
DW		 8242 /* raid4 can take over:
8243 * raid0 - if there is only one strip zone
8244 * raid5 - if layout is right
a78d38a1 8245 */
f1b29bca
DW		 8246 if (mddev->level == 0)
8247 return raid45_takeover_raid0(mddev, 4);
a78d38a1
N		 8248 if (mddev->level == 5 &&
8249 mddev->layout == ALGORITHM_PARITY_N) {
8250 mddev->new_layout = 0;
8251 mddev->new_level = 4;
8252 return setup_conf(mddev);
8253 }
8254 return ERR_PTR(-EINVAL);
8255}
d562b0c4 8256
84fc4b56 8257static struct md_personality raid5_personality;
245f46c2 8258
fd01b88c 8259static void *raid6_takeover(struct mddev *mddev)
245f46c2
N		 8260{
8261 /* Currently can only take over a raid5. We map the
8262 * personality to an equivalent raid6 personality
8263 * with the Q block at the end.
8264 */
8265 int new_layout;
8266
8267 if (mddev->pers != &raid5_personality)
8268 return ERR_PTR(-EINVAL);
8269 if (mddev->degraded > 1)
8270 return ERR_PTR(-EINVAL);
8271 if (mddev->raid_disks > 253)
8272 return ERR_PTR(-EINVAL);
8273 if (mddev->raid_disks < 3)
8274 return ERR_PTR(-EINVAL);
8275
8276 switch (mddev->layout) {
8277 case ALGORITHM_LEFT_ASYMMETRIC:
8278 new_layout = ALGORITHM_LEFT_ASYMMETRIC_6;
8279 break;
8280 case ALGORITHM_RIGHT_ASYMMETRIC:
8281 new_layout = ALGORITHM_RIGHT_ASYMMETRIC_6;
8282 break;
8283 case ALGORITHM_LEFT_SYMMETRIC:
8284 new_layout = ALGORITHM_LEFT_SYMMETRIC_6;
8285 break;
8286 case ALGORITHM_RIGHT_SYMMETRIC:
8287 new_layout = ALGORITHM_RIGHT_SYMMETRIC_6;
8288 break;
8289 case ALGORITHM_PARITY_0:
8290 new_layout = ALGORITHM_PARITY_0_6;
8291 break;
8292 case ALGORITHM_PARITY_N:
8293 new_layout = ALGORITHM_PARITY_N;
8294 break;
8295 default:
8296 return ERR_PTR(-EINVAL);
8297 }
8298 mddev->new_level = 6;
8299 mddev->new_layout = new_layout;
8300 mddev->delta_disks = 1;
8301 mddev->raid_disks += 1;
8302 return setup_conf(mddev);
8303}
8304
ba903a3e
AP		 8305static int raid5_change_consistency_policy(struct mddev *mddev, const char *buf)
8306{
8307 struct r5conf *conf;
8308 int err;
8309
8310 err = mddev_lock(mddev);
8311 if (err)
8312 return err;
8313 conf = mddev->private;
8314 if (!conf) {
8315 mddev_unlock(mddev);
8316 return -ENODEV;
8317 }
8318
845b9e22 8319 if (strncmp(buf, "ppl", 3) == 0) {
0bb0c105 8320 /* ppl only works with RAID 5 */
845b9e22
AP		 8321 if (!raid5_has_ppl(conf) && conf->level == 5) {
8322 err = log_init(conf, NULL, true);
8323 if (!err) {
8324 err = resize_stripes(conf, conf->pool_size);
8325 if (err)
8326 log_exit(conf);
8327 }
0bb0c105
SL		 8328 } else
8329 err = -EINVAL;
8330 } else if (strncmp(buf, "resync", 6) == 0) {
8331 if (raid5_has_ppl(conf)) {
8332 mddev_suspend(mddev);
8333 log_exit(conf);
0bb0c105 8334 mddev_resume(mddev);
845b9e22 8335 err = resize_stripes(conf, conf->pool_size);
0bb0c105
SL		 8336 } else if (test_bit(MD_HAS_JOURNAL, &conf->mddev->flags) &&
8337 r5l_log_disk_error(conf)) {
8338 bool journal_dev_exists = false;
8339 struct md_rdev *rdev;
8340
8341 rdev_for_each(rdev, mddev)
8342 if (test_bit(Journal, &rdev->flags)) {
8343 journal_dev_exists = true;
8344 break;
8345 }
8346
8347 if (!journal_dev_exists) {
8348 mddev_suspend(mddev);
8349 clear_bit(MD_HAS_JOURNAL, &mddev->flags);
8350 mddev_resume(mddev);
8351 } else /* need remove journal device first */
8352 err = -EBUSY;
8353 } else
8354 err = -EINVAL;
ba903a3e
AP		 8355 } else {
8356 err = -EINVAL;
8357 }
8358
8359 if (!err)
8360 md_update_sb(mddev, 1);
8361
8362 mddev_unlock(mddev);
8363
8364 return err;
8365}
8366
d5d885fd
SL		 8367static int raid5_start(struct mddev *mddev)
8368{
8369 struct r5conf *conf = mddev->private;
8370
8371 return r5l_start(conf->log);
8372}
8373
84fc4b56 8374static struct md_personality raid6_personality =
16a53ecc
N		 8375{
8376 .name = "raid6",
8377 .level = 6,
8378 .owner = THIS_MODULE,
849674e4
SL		 8379 .make_request = raid5_make_request,
8380 .run = raid5_run,
d5d885fd 8381 .start = raid5_start,
afa0f557 8382 .free = raid5_free,
849674e4
SL		 8383 .status = raid5_status,
8384 .error_handler = raid5_error,
16a53ecc
N		 8385 .hot_add_disk = raid5_add_disk,
8386 .hot_remove_disk= raid5_remove_disk,
8387 .spare_active = raid5_spare_active,
849674e4 8388 .sync_request = raid5_sync_request,
16a53ecc 8389 .resize = raid5_resize,
80c3a6ce 8390 .size = raid5_size,
50ac168a 8391 .check_reshape = raid6_check_reshape,
f416885e 8392 .start_reshape = raid5_start_reshape,
cea9c228 8393 .finish_reshape = raid5_finish_reshape,
16a53ecc 8394 .quiesce = raid5_quiesce,
245f46c2 8395 .takeover = raid6_takeover,
5c675f83 8396 .congested = raid5_congested,
0bb0c105 8397 .change_consistency_policy = raid5_change_consistency_policy,
16a53ecc 8398};
84fc4b56 8399static struct md_personality raid5_personality =
1da177e4
LT		 8400{
8401 .name = "raid5",
2604b703 8402 .level = 5,
1da177e4 8403 .owner = THIS_MODULE,
849674e4
SL		 8404 .make_request = raid5_make_request,
8405 .run = raid5_run,
d5d885fd 8406 .start = raid5_start,
afa0f557 8407 .free = raid5_free,
849674e4
SL		 8408 .status = raid5_status,
8409 .error_handler = raid5_error,
1da177e4
LT		 8410 .hot_add_disk = raid5_add_disk,
8411 .hot_remove_disk= raid5_remove_disk,
8412 .spare_active = raid5_spare_active,
849674e4 8413 .sync_request = raid5_sync_request,
1da177e4 8414 .resize = raid5_resize,
80c3a6ce 8415 .size = raid5_size,
63c70c4f
N		 8416 .check_reshape = raid5_check_reshape,
8417 .start_reshape = raid5_start_reshape,
cea9c228 8418 .finish_reshape = raid5_finish_reshape,
72626685 8419 .quiesce = raid5_quiesce,
d562b0c4 8420 .takeover = raid5_takeover,
5c675f83 8421 .congested = raid5_congested,
ba903a3e 8422 .change_consistency_policy = raid5_change_consistency_policy,
1da177e4
LT		 8423};
8424
84fc4b56 8425static struct md_personality raid4_personality =
1da177e4 8426{
2604b703
N		 8427 .name = "raid4",
8428 .level = 4,
8429 .owner = THIS_MODULE,
849674e4
SL		 8430 .make_request = raid5_make_request,
8431 .run = raid5_run,
d5d885fd 8432 .start = raid5_start,
afa0f557 8433 .free = raid5_free,
849674e4
SL		 8434 .status = raid5_status,
8435 .error_handler = raid5_error,
2604b703
N		 8436 .hot_add_disk = raid5_add_disk,
8437 .hot_remove_disk= raid5_remove_disk,
8438 .spare_active = raid5_spare_active,
849674e4 8439 .sync_request = raid5_sync_request,
2604b703 8440 .resize = raid5_resize,
80c3a6ce 8441 .size = raid5_size,
3d37890b
N		 8442 .check_reshape = raid5_check_reshape,
8443 .start_reshape = raid5_start_reshape,
cea9c228 8444 .finish_reshape = raid5_finish_reshape,
2604b703 8445 .quiesce = raid5_quiesce,
a78d38a1 8446 .takeover = raid4_takeover,
5c675f83 8447 .congested = raid5_congested,
0bb0c105 8448 .change_consistency_policy = raid5_change_consistency_policy,
2604b703
N		 8449};
8450
8451static int __init raid5_init(void)
8452{
29c6d1bb
SAS		 8453 int ret;
8454
851c30c9
SL		 8455 raid5_wq = alloc_workqueue("raid5wq",
8456 WQ_UNBOUND|WQ_MEM_RECLAIM|WQ_CPU_INTENSIVE|WQ_SYSFS, 0);
8457 if (!raid5_wq)
8458 return -ENOMEM;
29c6d1bb
SAS		 8459
8460 ret = cpuhp_setup_state_multi(CPUHP_MD_RAID5_PREPARE,
8461 "md/raid5:prepare",
8462 raid456_cpu_up_prepare,
8463 raid456_cpu_dead);
8464 if (ret) {
8465 destroy_workqueue(raid5_wq);
8466 return ret;
8467 }
16a53ecc 8468 register_md_personality(&raid6_personality);
2604b703
N		 8469 register_md_personality(&raid5_personality);
8470 register_md_personality(&raid4_personality);
8471 return 0;
1da177e4
LT		 8472}
8473
2604b703 8474static void raid5_exit(void)
1da177e4 8475{
16a53ecc 8476 unregister_md_personality(&raid6_personality);
2604b703
N		 8477 unregister_md_personality(&raid5_personality);
8478 unregister_md_personality(&raid4_personality);
29c6d1bb 8479 cpuhp_remove_multi_state(CPUHP_MD_RAID5_PREPARE);
851c30c9 8480 destroy_workqueue(raid5_wq);
1da177e4
LT		 8481}
8482
8483module_init(raid5_init);
8484module_exit(raid5_exit);
8485MODULE_LICENSE("GPL");
0efb9e61 8486MODULE_DESCRIPTION("RAID4/5/6 (striping with parity) personality for MD");
1da177e4 8487MODULE_ALIAS("md-personality-4"); /* RAID5 */
d9d166c2
N		 8488MODULE_ALIAS("md-raid5");
8489MODULE_ALIAS("md-raid4");
2604b703
N		 8490MODULE_ALIAS("md-level-5");
8491MODULE_ALIAS("md-level-4");
16a53ecc
N		 8492MODULE_ALIAS("md-personality-8"); /* RAID6 */
8493MODULE_ALIAS("md-raid6");
8494MODULE_ALIAS("md-level-6");
8495
8496/* This used to be two separate modules, they were: */
8497MODULE_ALIAS("raid5");
8498MODULE_ALIAS("raid6");
Linux 6.x block layer and io_uring tree(s)