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Merge branch 'pci/aspm'
[linux-2.6-block.git] / drivers / md / raid5.c
CommitLineData
af1a8899 1// SPDX-License-Identifier: GPL-2.0-or-later
1da177e4
LT		 2/*
3 * raid5.c : Multiple Devices driver for Linux
4 * Copyright (C) 1996, 1997 Ingo Molnar, Miguel de Icaza, Gadi Oxman
5 * Copyright (C) 1999, 2000 Ingo Molnar
16a53ecc 6 * Copyright (C) 2002, 2003 H. Peter Anvin
1da177e4 7 *
16a53ecc
N		 8 * RAID-4/5/6 management functions.
9 * Thanks to Penguin Computing for making the RAID-6 development possible
10 * by donating a test server!
1da177e4
LT		 11 */
12
ae3c20cc
N		 13/*
14 * BITMAP UNPLUGGING:
15 *
16 * The sequencing for updating the bitmap reliably is a little
17 * subtle (and I got it wrong the first time) so it deserves some
18 * explanation.
19 *
20 * We group bitmap updates into batches. Each batch has a number.
21 * We may write out several batches at once, but that isn't very important.
7c13edc8
N		 22 * conf->seq_write is the number of the last batch successfully written.
23 * conf->seq_flush is the number of the last batch that was closed to
ae3c20cc
N		 24 * new additions.
25 * When we discover that we will need to write to any block in a stripe
26 * (in add_stripe_bio) we update the in-memory bitmap and record in sh->bm_seq
7c13edc8 27 * the number of the batch it will be in. This is seq_flush+1.
ae3c20cc
N		 28 * When we are ready to do a write, if that batch hasn't been written yet,
29 * we plug the array and queue the stripe for later.
30 * When an unplug happens, we increment bm_flush, thus closing the current
31 * batch.
32 * When we notice that bm_flush > bm_write, we write out all pending updates
33 * to the bitmap, and advance bm_write to where bm_flush was.
34 * This may occasionally write a bit out twice, but is sure never to
35 * miss any bits.
36 */
1da177e4 37
bff61975 38#include <linux/blkdev.h>
f6705578 39#include <linux/kthread.h>
f701d589 40#include <linux/raid/pq.h>
91c00924 41#include <linux/async_tx.h>
056075c7 42#include <linux/module.h>
07a3b417 43#include <linux/async.h>
bff61975 44#include <linux/seq_file.h>
36d1c647 45#include <linux/cpu.h>
5a0e3ad6 46#include <linux/slab.h>
8bda470e 47#include <linux/ratelimit.h>
851c30c9 48#include <linux/nodemask.h>
3f07c014 49
a9add5d9 50#include <trace/events/block.h>
aaf9f12e 51#include <linux/list_sort.h>
a9add5d9 52
43b2e5d8 53#include "md.h"
bff61975 54#include "raid5.h"
54071b38 55#include "raid0.h"
935fe098 56#include "md-bitmap.h"
ff875738 57#include "raid5-log.h"
72626685 58
394ed8e4
SL		 59#define UNSUPPORTED_MDDEV_FLAGS (1L << MD_FAILFAST_SUPPORTED)
60
851c30c9
SL		 61#define cpu_to_group(cpu) cpu_to_node(cpu)
62#define ANY_GROUP NUMA_NO_NODE
63
8e0e99ba
N		 64static bool devices_handle_discard_safely = false;
65module_param(devices_handle_discard_safely, bool, 0644);
66MODULE_PARM_DESC(devices_handle_discard_safely,
67 "Set to Y if all devices in each array reliably return zeroes on reads from discarded regions");
851c30c9 68static struct workqueue_struct *raid5_wq;
1da177e4 69
d1688a6d 70static inline struct hlist_head *stripe_hash(struct r5conf *conf, sector_t sect)
db298e19
N		 71{
72 int hash = (sect >> STRIPE_SHIFT) & HASH_MASK;
73 return &conf->stripe_hashtbl[hash];
74}
1da177e4 75
566c09c5
SL		 76static inline int stripe_hash_locks_hash(sector_t sect)
77{
78 return (sect >> STRIPE_SHIFT) & STRIPE_HASH_LOCKS_MASK;
79}
80
81static inline void lock_device_hash_lock(struct r5conf *conf, int hash)
82{
83 spin_lock_irq(conf->hash_locks + hash);
84 spin_lock(&conf->device_lock);
85}
86
87static inline void unlock_device_hash_lock(struct r5conf *conf, int hash)
88{
89 spin_unlock(&conf->device_lock);
90 spin_unlock_irq(conf->hash_locks + hash);
91}
92
93static inline void lock_all_device_hash_locks_irq(struct r5conf *conf)
94{
95 int i;
3d05f3ae 96 spin_lock_irq(conf->hash_locks);
566c09c5
SL		 97 for (i = 1; i < NR_STRIPE_HASH_LOCKS; i++)
98 spin_lock_nest_lock(conf->hash_locks + i, conf->hash_locks);
99 spin_lock(&conf->device_lock);
100}
101
102static inline void unlock_all_device_hash_locks_irq(struct r5conf *conf)
103{
104 int i;
105 spin_unlock(&conf->device_lock);
3d05f3ae
JC		 106 for (i = NR_STRIPE_HASH_LOCKS - 1; i; i--)
107 spin_unlock(conf->hash_locks + i);
108 spin_unlock_irq(conf->hash_locks);
566c09c5
SL		 109}
110
d0dabf7e
N		 111/* Find first data disk in a raid6 stripe */
112static inline int raid6_d0(struct stripe_head *sh)
113{
67cc2b81
N		 114 if (sh->ddf_layout)
115 /* ddf always start from first device */
116 return 0;
117 /* md starts just after Q block */
d0dabf7e
N		 118 if (sh->qd_idx == sh->disks - 1)
119 return 0;
120 else
121 return sh->qd_idx + 1;
122}
16a53ecc
N		 123static inline int raid6_next_disk(int disk, int raid_disks)
124{
125 disk++;
126 return (disk < raid_disks) ? disk : 0;
127}
a4456856 128
d0dabf7e
N		 129/* When walking through the disks in a raid5, starting at raid6_d0,
130 * We need to map each disk to a 'slot', where the data disks are slot
131 * 0 .. raid_disks-3, the parity disk is raid_disks-2 and the Q disk
132 * is raid_disks-1. This help does that mapping.
133 */
67cc2b81
N		 134static int raid6_idx_to_slot(int idx, struct stripe_head *sh,
135 int *count, int syndrome_disks)
d0dabf7e 136{
6629542e 137 int slot = *count;
67cc2b81 138
e4424fee 139 if (sh->ddf_layout)
6629542e 140 (*count)++;
d0dabf7e 141 if (idx == sh->pd_idx)
67cc2b81 142 return syndrome_disks;
d0dabf7e 143 if (idx == sh->qd_idx)
67cc2b81 144 return syndrome_disks + 1;
e4424fee 145 if (!sh->ddf_layout)
6629542e 146 (*count)++;
d0dabf7e
N		 147 return slot;
148}
149
d1688a6d 150static void print_raid5_conf (struct r5conf *conf);
1da177e4 151
600aa109
DW		 152static int stripe_operations_active(struct stripe_head *sh)
153{
154 return sh->check_state || sh->reconstruct_state ||
155 test_bit(STRIPE_BIOFILL_RUN, &sh->state) ||
156 test_bit(STRIPE_COMPUTE_RUN, &sh->state);
157}
158
535ae4eb
SL		 159static bool stripe_is_lowprio(struct stripe_head *sh)
160{
161 return (test_bit(STRIPE_R5C_FULL_STRIPE, &sh->state) ||
162 test_bit(STRIPE_R5C_PARTIAL_STRIPE, &sh->state)) &&
163 !test_bit(STRIPE_R5C_CACHING, &sh->state);
164}
165
851c30c9
SL		 166static void raid5_wakeup_stripe_thread(struct stripe_head *sh)
167{
168 struct r5conf *conf = sh->raid_conf;
169 struct r5worker_group *group;
bfc90cb0 170 int thread_cnt;
851c30c9
SL		 171 int i, cpu = sh->cpu;
172
173 if (!cpu_online(cpu)) {
174 cpu = cpumask_any(cpu_online_mask);
175 sh->cpu = cpu;
176 }
177
178 if (list_empty(&sh->lru)) {
179 struct r5worker_group *group;
180 group = conf->worker_groups + cpu_to_group(cpu);
535ae4eb
SL		 181 if (stripe_is_lowprio(sh))
182 list_add_tail(&sh->lru, &group->loprio_list);
183 else
184 list_add_tail(&sh->lru, &group->handle_list);
bfc90cb0
SL		 185 group->stripes_cnt++;
186 sh->group = group;
851c30c9
SL		 187 }
188
189 if (conf->worker_cnt_per_group == 0) {
190 md_wakeup_thread(conf->mddev->thread);
191 return;
192 }
193
194 group = conf->worker_groups + cpu_to_group(sh->cpu);
195
bfc90cb0
SL		 196 group->workers[0].working = true;
197 /* at least one worker should run to avoid race */
198 queue_work_on(sh->cpu, raid5_wq, &group->workers[0].work);
199
200 thread_cnt = group->stripes_cnt / MAX_STRIPE_BATCH - 1;
201 /* wakeup more workers */
202 for (i = 1; i < conf->worker_cnt_per_group && thread_cnt > 0; i++) {
203 if (group->workers[i].working == false) {
204 group->workers[i].working = true;
205 queue_work_on(sh->cpu, raid5_wq,
206 &group->workers[i].work);
207 thread_cnt--;
208 }
209 }
851c30c9
SL		 210}
211
566c09c5
SL		 212static void do_release_stripe(struct r5conf *conf, struct stripe_head *sh,
213 struct list_head *temp_inactive_list)
1da177e4 214{
1e6d690b
SL		 215 int i;
216 int injournal = 0; /* number of date pages with R5_InJournal */
217
4eb788df
SL		 218 BUG_ON(!list_empty(&sh->lru));
219 BUG_ON(atomic_read(&conf->active_stripes)==0);
1e6d690b
SL		 220
221 if (r5c_is_writeback(conf->log))
222 for (i = sh->disks; i--; )
223 if (test_bit(R5_InJournal, &sh->dev[i].flags))
224 injournal++;
a39f7afd 225 /*
5ddf0440
SL		 226 * In the following cases, the stripe cannot be released to cached
227 * lists. Therefore, we make the stripe write out and set
228 * STRIPE_HANDLE:
229 * 1. when quiesce in r5c write back;
230 * 2. when resync is requested fot the stripe.
a39f7afd 231 */
5ddf0440
SL		 232 if (test_bit(STRIPE_SYNC_REQUESTED, &sh->state) ||
233 (conf->quiesce && r5c_is_writeback(conf->log) &&
234 !test_bit(STRIPE_HANDLE, &sh->state) && injournal != 0)) {
a39f7afd
SL		 235 if (test_bit(STRIPE_R5C_CACHING, &sh->state))
236 r5c_make_stripe_write_out(sh);
237 set_bit(STRIPE_HANDLE, &sh->state);
238 }
1e6d690b 239
4eb788df
SL		 240 if (test_bit(STRIPE_HANDLE, &sh->state)) {
241 if (test_bit(STRIPE_DELAYED, &sh->state) &&
ad3ab8b6 242 !test_bit(STRIPE_PREREAD_ACTIVE, &sh->state))
4eb788df 243 list_add_tail(&sh->lru, &conf->delayed_list);
ad3ab8b6 244 else if (test_bit(STRIPE_BIT_DELAY, &sh->state) &&
4eb788df
SL		 245 sh->bm_seq - conf->seq_write > 0)
246 list_add_tail(&sh->lru, &conf->bitmap_list);
247 else {
248 clear_bit(STRIPE_DELAYED, &sh->state);
249 clear_bit(STRIPE_BIT_DELAY, &sh->state);
851c30c9 250 if (conf->worker_cnt_per_group == 0) {
535ae4eb
SL		 251 if (stripe_is_lowprio(sh))
252 list_add_tail(&sh->lru,
253 &conf->loprio_list);
254 else
255 list_add_tail(&sh->lru,
256 &conf->handle_list);
851c30c9
SL		 257 } else {
258 raid5_wakeup_stripe_thread(sh);
259 return;
260 }
4eb788df
SL		 261 }
262 md_wakeup_thread(conf->mddev->thread);
263 } else {
264 BUG_ON(stripe_operations_active(sh));
265 if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE, &sh->state))
266 if (atomic_dec_return(&conf->preread_active_stripes)
267 < IO_THRESHOLD)
268 md_wakeup_thread(conf->mddev->thread);
269 atomic_dec(&conf->active_stripes);
1e6d690b
SL		 270 if (!test_bit(STRIPE_EXPANDING, &sh->state)) {
271 if (!r5c_is_writeback(conf->log))
272 list_add_tail(&sh->lru, temp_inactive_list);
273 else {
274 WARN_ON(test_bit(R5_InJournal, &sh->dev[sh->pd_idx].flags));
275 if (injournal == 0)
276 list_add_tail(&sh->lru, temp_inactive_list);
277 else if (injournal == conf->raid_disks - conf->max_degraded) {
278 /* full stripe */
279 if (!test_and_set_bit(STRIPE_R5C_FULL_STRIPE, &sh->state))
280 atomic_inc(&conf->r5c_cached_full_stripes);
281 if (test_and_clear_bit(STRIPE_R5C_PARTIAL_STRIPE, &sh->state))
282 atomic_dec(&conf->r5c_cached_partial_stripes);
283 list_add_tail(&sh->lru, &conf->r5c_full_stripe_list);
a39f7afd 284 r5c_check_cached_full_stripe(conf);
03b047f4
SL		 285 } else
286 /*
287 * STRIPE_R5C_PARTIAL_STRIPE is set in
288 * r5c_try_caching_write(). No need to
289 * set it again.
290 */
1e6d690b 291 list_add_tail(&sh->lru, &conf->r5c_partial_stripe_list);
1e6d690b
SL		 292 }
293 }
1da177e4
LT		 294 }
295}
d0dabf7e 296
566c09c5
SL		 297static void __release_stripe(struct r5conf *conf, struct stripe_head *sh,
298 struct list_head *temp_inactive_list)
4eb788df
SL		 299{
300 if (atomic_dec_and_test(&sh->count))
566c09c5
SL		 301 do_release_stripe(conf, sh, temp_inactive_list);
302}
303
304/*
305 * @hash could be NR_STRIPE_HASH_LOCKS, then we have a list of inactive_list
306 *
307 * Be careful: Only one task can add/delete stripes from temp_inactive_list at
308 * given time. Adding stripes only takes device lock, while deleting stripes
309 * only takes hash lock.
310 */
311static void release_inactive_stripe_list(struct r5conf *conf,
312 struct list_head *temp_inactive_list,
313 int hash)
314{
315 int size;
6ab2a4b8 316 bool do_wakeup = false;
566c09c5
SL		 317 unsigned long flags;
318
319 if (hash == NR_STRIPE_HASH_LOCKS) {
320 size = NR_STRIPE_HASH_LOCKS;
321 hash = NR_STRIPE_HASH_LOCKS - 1;
322 } else
323 size = 1;
324 while (size) {
325 struct list_head *list = &temp_inactive_list[size - 1];
326
327 /*
6d036f7d 328 * We don't hold any lock here yet, raid5_get_active_stripe() might
566c09c5
SL		 329 * remove stripes from the list
330 */
331 if (!list_empty_careful(list)) {
332 spin_lock_irqsave(conf->hash_locks + hash, flags);
4bda556a
SL		 333 if (list_empty(conf->inactive_list + hash) &&
334 !list_empty(list))
335 atomic_dec(&conf->empty_inactive_list_nr);
566c09c5 336 list_splice_tail_init(list, conf->inactive_list + hash);
6ab2a4b8 337 do_wakeup = true;
566c09c5
SL		 338 spin_unlock_irqrestore(conf->hash_locks + hash, flags);
339 }
340 size--;
341 hash--;
342 }
343
344 if (do_wakeup) {
6ab2a4b8 345 wake_up(&conf->wait_for_stripe);
b1b46486
YL		 346 if (atomic_read(&conf->active_stripes) == 0)
347 wake_up(&conf->wait_for_quiescent);
566c09c5
SL		 348 if (conf->retry_read_aligned)
349 md_wakeup_thread(conf->mddev->thread);
350 }
4eb788df
SL		 351}
352
773ca82f 353/* should hold conf->device_lock already */
566c09c5
SL		 354static int release_stripe_list(struct r5conf *conf,
355 struct list_head *temp_inactive_list)
773ca82f 356{
eae8263f 357 struct stripe_head *sh, *t;
773ca82f
SL		 358 int count = 0;
359 struct llist_node *head;
360
361 head = llist_del_all(&conf->released_stripes);
d265d9dc 362 head = llist_reverse_order(head);
eae8263f 363 llist_for_each_entry_safe(sh, t, head, release_list) {
566c09c5
SL		 364 int hash;
365
773ca82f
SL		 366 /* sh could be readded after STRIPE_ON_RELEASE_LIST is cleard */
367 smp_mb();
368 clear_bit(STRIPE_ON_RELEASE_LIST, &sh->state);
369 /*
370 * Don't worry the bit is set here, because if the bit is set
371 * again, the count is always > 1. This is true for
372 * STRIPE_ON_UNPLUG_LIST bit too.
373 */
566c09c5
SL		 374 hash = sh->hash_lock_index;
375 __release_stripe(conf, sh, &temp_inactive_list[hash]);
773ca82f
SL		 376 count++;
377 }
378
379 return count;
380}
381
6d036f7d 382void raid5_release_stripe(struct stripe_head *sh)
1da177e4 383{
d1688a6d 384 struct r5conf *conf = sh->raid_conf;
1da177e4 385 unsigned long flags;
566c09c5
SL		 386 struct list_head list;
387 int hash;
773ca82f 388 bool wakeup;
16a53ecc 389
cf170f3f
ES		 390 /* Avoid release_list until the last reference.
391 */
392 if (atomic_add_unless(&sh->count, -1, 1))
393 return;
394
ad4068de 395 if (unlikely(!conf->mddev->thread) ||
396 test_and_set_bit(STRIPE_ON_RELEASE_LIST, &sh->state))
773ca82f
SL		 397 goto slow_path;
398 wakeup = llist_add(&sh->release_list, &conf->released_stripes);
399 if (wakeup)
400 md_wakeup_thread(conf->mddev->thread);
401 return;
402slow_path:
773ca82f 403 /* we are ok here if STRIPE_ON_RELEASE_LIST is set or not */
685dbcaa 404 if (atomic_dec_and_lock_irqsave(&sh->count, &conf->device_lock, flags)) {
566c09c5
SL		 405 INIT_LIST_HEAD(&list);
406 hash = sh->hash_lock_index;
407 do_release_stripe(conf, sh, &list);
08edaaa6 408 spin_unlock_irqrestore(&conf->device_lock, flags);
566c09c5 409 release_inactive_stripe_list(conf, &list, hash);
4eb788df 410 }
1da177e4
LT		 411}
412
fccddba0 413static inline void remove_hash(struct stripe_head *sh)
1da177e4 414{
45b4233c
DW		 415 pr_debug("remove_hash(), stripe %llu\n",
416 (unsigned long long)sh->sector);
1da177e4 417
fccddba0 418 hlist_del_init(&sh->hash);
1da177e4
LT		 419}
420
d1688a6d 421static inline void insert_hash(struct r5conf *conf, struct stripe_head *sh)
1da177e4 422{
fccddba0 423 struct hlist_head *hp = stripe_hash(conf, sh->sector);
1da177e4 424
45b4233c
DW		 425 pr_debug("insert_hash(), stripe %llu\n",
426 (unsigned long long)sh->sector);
1da177e4 427
fccddba0 428 hlist_add_head(&sh->hash, hp);
1da177e4
LT		 429}
430
1da177e4 431/* find an idle stripe, make sure it is unhashed, and return it. */
566c09c5 432static struct stripe_head *get_free_stripe(struct r5conf *conf, int hash)
1da177e4
LT		 433{
434 struct stripe_head *sh = NULL;
435 struct list_head *first;
436
566c09c5 437 if (list_empty(conf->inactive_list + hash))
1da177e4 438 goto out;
566c09c5 439 first = (conf->inactive_list + hash)->next;
1da177e4
LT		 440 sh = list_entry(first, struct stripe_head, lru);
441 list_del_init(first);
442 remove_hash(sh);
443 atomic_inc(&conf->active_stripes);
566c09c5 444 BUG_ON(hash != sh->hash_lock_index);
4bda556a
SL		 445 if (list_empty(conf->inactive_list + hash))
446 atomic_inc(&conf->empty_inactive_list_nr);
1da177e4
LT		 447out:
448 return sh;
449}
450
e4e11e38 451static void shrink_buffers(struct stripe_head *sh)
1da177e4
LT		 452{
453 struct page *p;
454 int i;
e4e11e38 455 int num = sh->raid_conf->pool_size;
1da177e4 456
e4e11e38 457 for (i = 0; i < num ; i++) {
d592a996 458 WARN_ON(sh->dev[i].page != sh->dev[i].orig_page);
1da177e4
LT		 459 p = sh->dev[i].page;
460 if (!p)
461 continue;
462 sh->dev[i].page = NULL;
2d1f3b5d 463 put_page(p);
1da177e4
LT		 464 }
465}
466
a9683a79 467static int grow_buffers(struct stripe_head *sh, gfp_t gfp)
1da177e4
LT		 468{
469 int i;
e4e11e38 470 int num = sh->raid_conf->pool_size;
1da177e4 471
e4e11e38 472 for (i = 0; i < num; i++) {
1da177e4
LT		 473 struct page *page;
474
a9683a79 475 if (!(page = alloc_page(gfp))) {
1da177e4
LT		 476 return 1;
477 }
478 sh->dev[i].page = page;
d592a996 479 sh->dev[i].orig_page = page;
1da177e4 480 }
3418d036 481
1da177e4
LT		 482 return 0;
483}
484
d1688a6d 485static void stripe_set_idx(sector_t stripe, struct r5conf *conf, int previous,
911d4ee8 486 struct stripe_head *sh);
1da177e4 487
b5663ba4 488static void init_stripe(struct stripe_head *sh, sector_t sector, int previous)
1da177e4 489{
d1688a6d 490 struct r5conf *conf = sh->raid_conf;
566c09c5 491 int i, seq;
1da177e4 492
78bafebd
ES		 493 BUG_ON(atomic_read(&sh->count) != 0);
494 BUG_ON(test_bit(STRIPE_HANDLE, &sh->state));
600aa109 495 BUG_ON(stripe_operations_active(sh));
59fc630b 496 BUG_ON(sh->batch_head);
d84e0f10 497
45b4233c 498 pr_debug("init_stripe called, stripe %llu\n",
b8e6a15a 499 (unsigned long long)sector);
566c09c5
SL		 500retry:
501 seq = read_seqcount_begin(&conf->gen_lock);
86b42c71 502 sh->generation = conf->generation - previous;
b5663ba4 503 sh->disks = previous ? conf->previous_raid_disks : conf->raid_disks;
1da177e4 504 sh->sector = sector;
911d4ee8 505 stripe_set_idx(sector, conf, previous, sh);
1da177e4
LT		 506 sh->state = 0;
507
7ecaa1e6 508 for (i = sh->disks; i--; ) {
1da177e4
LT		 509 struct r5dev *dev = &sh->dev[i];
510
d84e0f10 511 if (dev->toread || dev->read || dev->towrite || dev->written ||
1da177e4 512 test_bit(R5_LOCKED, &dev->flags)) {
cc6167b4 513 pr_err("sector=%llx i=%d %p %p %p %p %d\n",
1da177e4 514 (unsigned long long)sh->sector, i, dev->toread,
d84e0f10 515 dev->read, dev->towrite, dev->written,
1da177e4 516 test_bit(R5_LOCKED, &dev->flags));
8cfa7b0f 517 WARN_ON(1);
1da177e4
LT		 518 }
519 dev->flags = 0;
27a4ff8f 520 dev->sector = raid5_compute_blocknr(sh, i, previous);
1da177e4 521 }
566c09c5
SL		 522 if (read_seqcount_retry(&conf->gen_lock, seq))
523 goto retry;
7a87f434 524 sh->overwrite_disks = 0;
1da177e4 525 insert_hash(conf, sh);
851c30c9 526 sh->cpu = smp_processor_id();
da41ba65 527 set_bit(STRIPE_BATCH_READY, &sh->state);
1da177e4
LT		 528}
529
d1688a6d 530static struct stripe_head *__find_stripe(struct r5conf *conf, sector_t sector,
86b42c71 531 short generation)
1da177e4
LT		 532{
533 struct stripe_head *sh;
534
45b4233c 535 pr_debug("__find_stripe, sector %llu\n", (unsigned long long)sector);
b67bfe0d 536 hlist_for_each_entry(sh, stripe_hash(conf, sector), hash)
86b42c71 537 if (sh->sector == sector && sh->generation == generation)
1da177e4 538 return sh;
45b4233c 539 pr_debug("__stripe %llu not in cache\n", (unsigned long long)sector);
1da177e4
LT		 540 return NULL;
541}
542
674806d6
N		 543/*
544 * Need to check if array has failed when deciding whether to:
545 * - start an array
546 * - remove non-faulty devices
547 * - add a spare
548 * - allow a reshape
549 * This determination is simple when no reshape is happening.
550 * However if there is a reshape, we need to carefully check
551 * both the before and after sections.
552 * This is because some failed devices may only affect one
553 * of the two sections, and some non-in_sync devices may
554 * be insync in the section most affected by failed devices.
555 */
2e38a37f 556int raid5_calc_degraded(struct r5conf *conf)
674806d6 557{
908f4fbd 558 int degraded, degraded2;
674806d6 559 int i;
674806d6
N		 560
561 rcu_read_lock();
562 degraded = 0;
563 for (i = 0; i < conf->previous_raid_disks; i++) {
3cb03002 564 struct md_rdev *rdev = rcu_dereference(conf->disks[i].rdev);
e5c86471
N		 565 if (rdev && test_bit(Faulty, &rdev->flags))
566 rdev = rcu_dereference(conf->disks[i].replacement);
674806d6
N		 567 if (!rdev || test_bit(Faulty, &rdev->flags))
568 degraded++;
569 else if (test_bit(In_sync, &rdev->flags))
570 ;
571 else
572 /* not in-sync or faulty.
573 * If the reshape increases the number of devices,
574 * this is being recovered by the reshape, so
575 * this 'previous' section is not in_sync.
576 * If the number of devices is being reduced however,
577 * the device can only be part of the array if
578 * we are reverting a reshape, so this section will
579 * be in-sync.
580 */
581 if (conf->raid_disks >= conf->previous_raid_disks)
582 degraded++;
583 }
584 rcu_read_unlock();
908f4fbd
N		 585 if (conf->raid_disks == conf->previous_raid_disks)
586 return degraded;
674806d6 587 rcu_read_lock();
908f4fbd 588 degraded2 = 0;
674806d6 589 for (i = 0; i < conf->raid_disks; i++) {
3cb03002 590 struct md_rdev *rdev = rcu_dereference(conf->disks[i].rdev);
e5c86471
N		 591 if (rdev && test_bit(Faulty, &rdev->flags))
592 rdev = rcu_dereference(conf->disks[i].replacement);
674806d6 593 if (!rdev || test_bit(Faulty, &rdev->flags))
908f4fbd 594 degraded2++;
674806d6
N		 595 else if (test_bit(In_sync, &rdev->flags))
596 ;
597 else
598 /* not in-sync or faulty.
599 * If reshape increases the number of devices, this
600 * section has already been recovered, else it
601 * almost certainly hasn't.
602 */
603 if (conf->raid_disks <= conf->previous_raid_disks)
908f4fbd 604 degraded2++;
674806d6
N		 605 }
606 rcu_read_unlock();
908f4fbd
N		 607 if (degraded2 > degraded)
608 return degraded2;
609 return degraded;
610}
611
612static int has_failed(struct r5conf *conf)
613{
614 int degraded;
615
616 if (conf->mddev->reshape_position == MaxSector)
617 return conf->mddev->degraded > conf->max_degraded;
618
2e38a37f 619 degraded = raid5_calc_degraded(conf);
674806d6
N		 620 if (degraded > conf->max_degraded)
621 return 1;
622 return 0;
623}
624
6d036f7d
SL		 625struct stripe_head *
626raid5_get_active_stripe(struct r5conf *conf, sector_t sector,
627 int previous, int noblock, int noquiesce)
1da177e4
LT		 628{
629 struct stripe_head *sh;
566c09c5 630 int hash = stripe_hash_locks_hash(sector);
ff00d3b4 631 int inc_empty_inactive_list_flag;
1da177e4 632
45b4233c 633 pr_debug("get_stripe, sector %llu\n", (unsigned long long)sector);
1da177e4 634
566c09c5 635 spin_lock_irq(conf->hash_locks + hash);
1da177e4
LT		 636
637 do {
b1b46486 638 wait_event_lock_irq(conf->wait_for_quiescent,
a8c906ca 639 conf->quiesce == 0 || noquiesce,
566c09c5 640 *(conf->hash_locks + hash));
86b42c71 641 sh = __find_stripe(conf, sector, conf->generation - previous);
1da177e4 642 if (!sh) {
edbe83ab 643 if (!test_bit(R5_INACTIVE_BLOCKED, &conf->cache_state)) {
566c09c5 644 sh = get_free_stripe(conf, hash);
713bc5c2
SL		 645 if (!sh && !test_bit(R5_DID_ALLOC,
646 &conf->cache_state))
edbe83ab
N		 647 set_bit(R5_ALLOC_MORE,
648 &conf->cache_state);
649 }
1da177e4
LT		 650 if (noblock && sh == NULL)
651 break;
a39f7afd
SL		 652
653 r5c_check_stripe_cache_usage(conf);
1da177e4 654 if (!sh) {
5423399a
N		 655 set_bit(R5_INACTIVE_BLOCKED,
656 &conf->cache_state);
a39f7afd 657 r5l_wake_reclaim(conf->log, 0);
6ab2a4b8
SL		 658 wait_event_lock_irq(
659 conf->wait_for_stripe,
566c09c5
SL		 660 !list_empty(conf->inactive_list + hash) &&
661 (atomic_read(&conf->active_stripes)
662 < (conf->max_nr_stripes * 3 / 4)
5423399a
N		 663 || !test_bit(R5_INACTIVE_BLOCKED,
664 &conf->cache_state)),
6ab2a4b8 665 *(conf->hash_locks + hash));
5423399a
N		 666 clear_bit(R5_INACTIVE_BLOCKED,
667 &conf->cache_state);
7da9d450 668 } else {
b5663ba4 669 init_stripe(sh, sector, previous);
7da9d450
N		 670 atomic_inc(&sh->count);
671 }
e240c183 672 } else if (!atomic_inc_not_zero(&sh->count)) {
6d183de4 673 spin_lock(&conf->device_lock);
e240c183 674 if (!atomic_read(&sh->count)) {
1da177e4
LT		 675 if (!test_bit(STRIPE_HANDLE, &sh->state))
676 atomic_inc(&conf->active_stripes);
5af9bef7
N		 677 BUG_ON(list_empty(&sh->lru) &&
678 !test_bit(STRIPE_EXPANDING, &sh->state));
ff00d3b4
ZL		 679 inc_empty_inactive_list_flag = 0;
680 if (!list_empty(conf->inactive_list + hash))
681 inc_empty_inactive_list_flag = 1;
16a53ecc 682 list_del_init(&sh->lru);
ff00d3b4
ZL		 683 if (list_empty(conf->inactive_list + hash) && inc_empty_inactive_list_flag)
684 atomic_inc(&conf->empty_inactive_list_nr);
bfc90cb0
SL		 685 if (sh->group) {
686 sh->group->stripes_cnt--;
687 sh->group = NULL;
688 }
1da177e4 689 }
7da9d450 690 atomic_inc(&sh->count);
6d183de4 691 spin_unlock(&conf->device_lock);
1da177e4
LT		 692 }
693 } while (sh == NULL);
694
566c09c5 695 spin_unlock_irq(conf->hash_locks + hash);
1da177e4
LT		 696 return sh;
697}
698
7a87f434 699static bool is_full_stripe_write(struct stripe_head *sh)
700{
701 BUG_ON(sh->overwrite_disks > (sh->disks - sh->raid_conf->max_degraded));
702 return sh->overwrite_disks == (sh->disks - sh->raid_conf->max_degraded);
703}
704
59fc630b 705static void lock_two_stripes(struct stripe_head *sh1, struct stripe_head *sh2)
368ecade
CH		 706 __acquires(&sh1->stripe_lock)
707 __acquires(&sh2->stripe_lock)
59fc630b 708{
59fc630b 709 if (sh1 > sh2) {
3d05f3ae 710 spin_lock_irq(&sh2->stripe_lock);
59fc630b 711 spin_lock_nested(&sh1->stripe_lock, 1);
712 } else {
3d05f3ae 713 spin_lock_irq(&sh1->stripe_lock);
59fc630b 714 spin_lock_nested(&sh2->stripe_lock, 1);
715 }
716}
717
718static void unlock_two_stripes(struct stripe_head *sh1, struct stripe_head *sh2)
368ecade
CH		 719 __releases(&sh1->stripe_lock)
720 __releases(&sh2->stripe_lock)
59fc630b 721{
722 spin_unlock(&sh1->stripe_lock);
3d05f3ae 723 spin_unlock_irq(&sh2->stripe_lock);
59fc630b 724}
725
726/* Only freshly new full stripe normal write stripe can be added to a batch list */
727static bool stripe_can_batch(struct stripe_head *sh)
728{
9c3e333d
SL		 729 struct r5conf *conf = sh->raid_conf;
730
e254de6b 731 if (raid5_has_log(conf) || raid5_has_ppl(conf))
9c3e333d 732 return false;
59fc630b 733 return test_bit(STRIPE_BATCH_READY, &sh->state) &&
d0852df5 734 !test_bit(STRIPE_BITMAP_PENDING, &sh->state) &&
59fc630b 735 is_full_stripe_write(sh);
736}
737
738/* we only do back search */
739static void stripe_add_to_batch_list(struct r5conf *conf, struct stripe_head *sh)
740{
741 struct stripe_head *head;
742 sector_t head_sector, tmp_sec;
743 int hash;
744 int dd_idx;
ff00d3b4 745 int inc_empty_inactive_list_flag;
59fc630b 746
59fc630b 747 /* Don't cross chunks, so stripe pd_idx/qd_idx is the same */
748 tmp_sec = sh->sector;
749 if (!sector_div(tmp_sec, conf->chunk_sectors))
750 return;
751 head_sector = sh->sector - STRIPE_SECTORS;
752
753 hash = stripe_hash_locks_hash(head_sector);
754 spin_lock_irq(conf->hash_locks + hash);
755 head = __find_stripe(conf, head_sector, conf->generation);
756 if (head && !atomic_inc_not_zero(&head->count)) {
757 spin_lock(&conf->device_lock);
758 if (!atomic_read(&head->count)) {
759 if (!test_bit(STRIPE_HANDLE, &head->state))
760 atomic_inc(&conf->active_stripes);
761 BUG_ON(list_empty(&head->lru) &&
762 !test_bit(STRIPE_EXPANDING, &head->state));
ff00d3b4
ZL		 763 inc_empty_inactive_list_flag = 0;
764 if (!list_empty(conf->inactive_list + hash))
765 inc_empty_inactive_list_flag = 1;
59fc630b 766 list_del_init(&head->lru);
ff00d3b4
ZL		 767 if (list_empty(conf->inactive_list + hash) && inc_empty_inactive_list_flag)
768 atomic_inc(&conf->empty_inactive_list_nr);
59fc630b 769 if (head->group) {
770 head->group->stripes_cnt--;
771 head->group = NULL;
772 }
773 }
774 atomic_inc(&head->count);
775 spin_unlock(&conf->device_lock);
776 }
777 spin_unlock_irq(conf->hash_locks + hash);
778
779 if (!head)
780 return;
781 if (!stripe_can_batch(head))
782 goto out;
783
784 lock_two_stripes(head, sh);
785 /* clear_batch_ready clear the flag */
786 if (!stripe_can_batch(head) || !stripe_can_batch(sh))
787 goto unlock_out;
788
789 if (sh->batch_head)
790 goto unlock_out;
791
792 dd_idx = 0;
793 while (dd_idx == sh->pd_idx || dd_idx == sh->qd_idx)
794 dd_idx++;
1eff9d32 795 if (head->dev[dd_idx].towrite->bi_opf != sh->dev[dd_idx].towrite->bi_opf ||
796a5cf0 796 bio_op(head->dev[dd_idx].towrite) != bio_op(sh->dev[dd_idx].towrite))
59fc630b 797 goto unlock_out;
798
799 if (head->batch_head) {
800 spin_lock(&head->batch_head->batch_lock);
801 /* This batch list is already running */
802 if (!stripe_can_batch(head)) {
803 spin_unlock(&head->batch_head->batch_lock);
804 goto unlock_out;
805 }
3664847d
SL		 806 /*
807 * We must assign batch_head of this stripe within the
808 * batch_lock, otherwise clear_batch_ready of batch head
809 * stripe could clear BATCH_READY bit of this stripe and
810 * this stripe->batch_head doesn't get assigned, which
811 * could confuse clear_batch_ready for this stripe
812 */
813 sh->batch_head = head->batch_head;
59fc630b 814
815 /*
816 * at this point, head's BATCH_READY could be cleared, but we
817 * can still add the stripe to batch list
818 */
819 list_add(&sh->batch_list, &head->batch_list);
820 spin_unlock(&head->batch_head->batch_lock);
59fc630b 821 } else {
822 head->batch_head = head;
823 sh->batch_head = head->batch_head;
824 spin_lock(&head->batch_lock);
825 list_add_tail(&sh->batch_list, &head->batch_list);
826 spin_unlock(&head->batch_lock);
827 }
828
829 if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE, &sh->state))
830 if (atomic_dec_return(&conf->preread_active_stripes)
831 < IO_THRESHOLD)
832 md_wakeup_thread(conf->mddev->thread);
833
2b6b2457
N		 834 if (test_and_clear_bit(STRIPE_BIT_DELAY, &sh->state)) {
835 int seq = sh->bm_seq;
836 if (test_bit(STRIPE_BIT_DELAY, &sh->batch_head->state) &&
837 sh->batch_head->bm_seq > seq)
838 seq = sh->batch_head->bm_seq;
839 set_bit(STRIPE_BIT_DELAY, &sh->batch_head->state);
840 sh->batch_head->bm_seq = seq;
841 }
842
59fc630b 843 atomic_inc(&sh->count);
844unlock_out:
845 unlock_two_stripes(head, sh);
846out:
6d036f7d 847 raid5_release_stripe(head);
59fc630b 848}
849
05616be5
N		 850/* Determine if 'data_offset' or 'new_data_offset' should be used
851 * in this stripe_head.
852 */
853static int use_new_offset(struct r5conf *conf, struct stripe_head *sh)
854{
855 sector_t progress = conf->reshape_progress;
856 /* Need a memory barrier to make sure we see the value
857 * of conf->generation, or ->data_offset that was set before
858 * reshape_progress was updated.
859 */
860 smp_rmb();
861 if (progress == MaxSector)
862 return 0;
863 if (sh->generation == conf->generation - 1)
864 return 0;
865 /* We are in a reshape, and this is a new-generation stripe,
866 * so use new_data_offset.
867 */
868 return 1;
869}
870
aaf9f12e 871static void dispatch_bio_list(struct bio_list *tmp)
765d704d 872{
765d704d
SL		 873 struct bio *bio;
874
aaf9f12e
SL		 875 while ((bio = bio_list_pop(tmp)))
876 generic_make_request(bio);
877}
878
879static int cmp_stripe(void *priv, struct list_head *a, struct list_head *b)
880{
881 const struct r5pending_data *da = list_entry(a,
882 struct r5pending_data, sibling);
883 const struct r5pending_data *db = list_entry(b,
884 struct r5pending_data, sibling);
885 if (da->sector > db->sector)
886 return 1;
887 if (da->sector < db->sector)
888 return -1;
889 return 0;
890}
891
892static void dispatch_defer_bios(struct r5conf *conf, int target,
893 struct bio_list *list)
894{
895 struct r5pending_data *data;
896 struct list_head *first, *next = NULL;
897 int cnt = 0;
898
899 if (conf->pending_data_cnt == 0)
900 return;
901
902 list_sort(NULL, &conf->pending_list, cmp_stripe);
903
904 first = conf->pending_list.next;
905
906 /* temporarily move the head */
907 if (conf->next_pending_data)
908 list_move_tail(&conf->pending_list,
909 &conf->next_pending_data->sibling);
910
911 while (!list_empty(&conf->pending_list)) {
912 data = list_first_entry(&conf->pending_list,
913 struct r5pending_data, sibling);
914 if (&data->sibling == first)
915 first = data->sibling.next;
916 next = data->sibling.next;
917
918 bio_list_merge(list, &data->bios);
919 list_move(&data->sibling, &conf->free_list);
920 cnt++;
921 if (cnt >= target)
922 break;
923 }
924 conf->pending_data_cnt -= cnt;
925 BUG_ON(conf->pending_data_cnt < 0 || cnt < target);
926
927 if (next != &conf->pending_list)
928 conf->next_pending_data = list_entry(next,
929 struct r5pending_data, sibling);
930 else
931 conf->next_pending_data = NULL;
932 /* list isn't empty */
933 if (first != &conf->pending_list)
934 list_move_tail(&conf->pending_list, first);
935}
936
937static void flush_deferred_bios(struct r5conf *conf)
938{
939 struct bio_list tmp = BIO_EMPTY_LIST;
940
941 if (conf->pending_data_cnt == 0)
765d704d
SL		 942 return;
943
765d704d 944 spin_lock(&conf->pending_bios_lock);
aaf9f12e
SL		 945 dispatch_defer_bios(conf, conf->pending_data_cnt, &tmp);
946 BUG_ON(conf->pending_data_cnt != 0);
765d704d
SL		 947 spin_unlock(&conf->pending_bios_lock);
948
aaf9f12e 949 dispatch_bio_list(&tmp);
765d704d
SL		 950}
951
aaf9f12e
SL		 952static void defer_issue_bios(struct r5conf *conf, sector_t sector,
953 struct bio_list *bios)
765d704d 954{
aaf9f12e
SL		 955 struct bio_list tmp = BIO_EMPTY_LIST;
956 struct r5pending_data *ent;
957
765d704d 958 spin_lock(&conf->pending_bios_lock);
aaf9f12e
SL		 959 ent = list_first_entry(&conf->free_list, struct r5pending_data,
960 sibling);
961 list_move_tail(&ent->sibling, &conf->pending_list);
962 ent->sector = sector;
963 bio_list_init(&ent->bios);
964 bio_list_merge(&ent->bios, bios);
965 conf->pending_data_cnt++;
966 if (conf->pending_data_cnt >= PENDING_IO_MAX)
967 dispatch_defer_bios(conf, PENDING_IO_ONE_FLUSH, &tmp);
968
765d704d 969 spin_unlock(&conf->pending_bios_lock);
aaf9f12e
SL		 970
971 dispatch_bio_list(&tmp);
765d704d
SL		 972}
973
6712ecf8 974static void
4246a0b6 975raid5_end_read_request(struct bio *bi);
6712ecf8 976static void
4246a0b6 977raid5_end_write_request(struct bio *bi);
91c00924 978
c4e5ac0a 979static void ops_run_io(struct stripe_head *sh, struct stripe_head_state *s)
91c00924 980{
d1688a6d 981 struct r5conf *conf = sh->raid_conf;
91c00924 982 int i, disks = sh->disks;
59fc630b 983 struct stripe_head *head_sh = sh;
aaf9f12e
SL		 984 struct bio_list pending_bios = BIO_EMPTY_LIST;
985 bool should_defer;
91c00924
DW		 986
987 might_sleep();
988
ff875738
AP		 989 if (log_stripe(sh, s) == 0)
990 return;
1e6d690b 991
aaf9f12e 992 should_defer = conf->batch_bio_dispatch && conf->group_cnt;
1e6d690b 993
91c00924 994 for (i = disks; i--; ) {
796a5cf0 995 int op, op_flags = 0;
9a3e1101 996 int replace_only = 0;
977df362
N		 997 struct bio *bi, *rbi;
998 struct md_rdev *rdev, *rrdev = NULL;
59fc630b 999
1000 sh = head_sh;
e9c7469b 1001 if (test_and_clear_bit(R5_Wantwrite, &sh->dev[i].flags)) {
796a5cf0 1002 op = REQ_OP_WRITE;
e9c7469b 1003 if (test_and_clear_bit(R5_WantFUA, &sh->dev[i].flags))
70fd7614 1004 op_flags = REQ_FUA;
9e444768 1005 if (test_bit(R5_Discard, &sh->dev[i].flags))
796a5cf0 1006 op = REQ_OP_DISCARD;
e9c7469b 1007 } else if (test_and_clear_bit(R5_Wantread, &sh->dev[i].flags))
796a5cf0 1008 op = REQ_OP_READ;
9a3e1101
N		 1009 else if (test_and_clear_bit(R5_WantReplace,
1010 &sh->dev[i].flags)) {
796a5cf0 1011 op = REQ_OP_WRITE;
9a3e1101
N		 1012 replace_only = 1;
1013 } else
91c00924 1014 continue;
bc0934f0 1015 if (test_and_clear_bit(R5_SyncIO, &sh->dev[i].flags))
796a5cf0 1016 op_flags |= REQ_SYNC;
91c00924 1017
59fc630b 1018again:
91c00924 1019 bi = &sh->dev[i].req;
977df362 1020 rbi = &sh->dev[i].rreq; /* For writing to replacement */
91c00924 1021
91c00924 1022 rcu_read_lock();
9a3e1101 1023 rrdev = rcu_dereference(conf->disks[i].replacement);
dd054fce
N		 1024 smp_mb(); /* Ensure that if rrdev is NULL, rdev won't be */
1025 rdev = rcu_dereference(conf->disks[i].rdev);
1026 if (!rdev) {
1027 rdev = rrdev;
1028 rrdev = NULL;
1029 }
796a5cf0 1030 if (op_is_write(op)) {
9a3e1101
N		 1031 if (replace_only)
1032 rdev = NULL;
dd054fce
N		 1033 if (rdev == rrdev)
1034 /* We raced and saw duplicates */
1035 rrdev = NULL;
9a3e1101 1036 } else {
59fc630b 1037 if (test_bit(R5_ReadRepl, &head_sh->dev[i].flags) && rrdev)
9a3e1101
N		 1038 rdev = rrdev;
1039 rrdev = NULL;
1040 }
977df362 1041
91c00924
DW		 1042 if (rdev && test_bit(Faulty, &rdev->flags))
1043 rdev = NULL;
1044 if (rdev)
1045 atomic_inc(&rdev->nr_pending);
977df362
N		 1046 if (rrdev && test_bit(Faulty, &rrdev->flags))
1047 rrdev = NULL;
1048 if (rrdev)
1049 atomic_inc(&rrdev->nr_pending);
91c00924
DW		 1050 rcu_read_unlock();
1051
73e92e51 1052 /* We have already checked bad blocks for reads. Now
977df362
N		 1053 * need to check for writes. We never accept write errors
1054 * on the replacement, so we don't to check rrdev.
73e92e51 1055 */
796a5cf0 1056 while (op_is_write(op) && rdev &&
73e92e51
N		 1057 test_bit(WriteErrorSeen, &rdev->flags)) {
1058 sector_t first_bad;
1059 int bad_sectors;
1060 int bad = is_badblock(rdev, sh->sector, STRIPE_SECTORS,
1061 &first_bad, &bad_sectors);
1062 if (!bad)
1063 break;
1064
1065 if (bad < 0) {
1066 set_bit(BlockedBadBlocks, &rdev->flags);
1067 if (!conf->mddev->external &&
2953079c 1068 conf->mddev->sb_flags) {
73e92e51
N		 1069 /* It is very unlikely, but we might
1070 * still need to write out the
1071 * bad block log - better give it
1072 * a chance*/
1073 md_check_recovery(conf->mddev);
1074 }
1850753d 1075 /*
1076 * Because md_wait_for_blocked_rdev
1077 * will dec nr_pending, we must
1078 * increment it first.
1079 */
1080 atomic_inc(&rdev->nr_pending);
73e92e51
N		 1081 md_wait_for_blocked_rdev(rdev, conf->mddev);
1082 } else {
1083 /* Acknowledged bad block - skip the write */
1084 rdev_dec_pending(rdev, conf->mddev);
1085 rdev = NULL;
1086 }
1087 }
1088
91c00924 1089 if (rdev) {
9a3e1101
N		 1090 if (s->syncing || s->expanding || s->expanded
1091 || s->replacing)
91c00924
DW		 1092 md_sync_acct(rdev->bdev, STRIPE_SECTORS);
1093
2b7497f0
DW		 1094 set_bit(STRIPE_IO_STARTED, &sh->state);
1095
74d46992 1096 bio_set_dev(bi, rdev->bdev);
796a5cf0
MC		 1097 bio_set_op_attrs(bi, op, op_flags);
1098 bi->bi_end_io = op_is_write(op)
2f6db2a7
KO		 1099 ? raid5_end_write_request
1100 : raid5_end_read_request;
1101 bi->bi_private = sh;
1102
6296b960 1103 pr_debug("%s: for %llu schedule op %d on disc %d\n",
e46b272b 1104 __func__, (unsigned long long)sh->sector,
1eff9d32 1105 bi->bi_opf, i);
91c00924 1106 atomic_inc(&sh->count);
59fc630b 1107 if (sh != head_sh)
1108 atomic_inc(&head_sh->count);
05616be5 1109 if (use_new_offset(conf, sh))
4f024f37 1110 bi->bi_iter.bi_sector = (sh->sector
05616be5
N		 1111 + rdev->new_data_offset);
1112 else
4f024f37 1113 bi->bi_iter.bi_sector = (sh->sector
05616be5 1114 + rdev->data_offset);
59fc630b 1115 if (test_bit(R5_ReadNoMerge, &head_sh->dev[i].flags))
1eff9d32 1116 bi->bi_opf |= REQ_NOMERGE;
3f9e7c14 1117
d592a996
SL		 1118 if (test_bit(R5_SkipCopy, &sh->dev[i].flags))
1119 WARN_ON(test_bit(R5_UPTODATE, &sh->dev[i].flags));
86aa1397
SL		 1120
1121 if (!op_is_write(op) &&
1122 test_bit(R5_InJournal, &sh->dev[i].flags))
1123 /*
1124 * issuing read for a page in journal, this
1125 * must be preparing for prexor in rmw; read
1126 * the data into orig_page
1127 */
1128 sh->dev[i].vec.bv_page = sh->dev[i].orig_page;
1129 else
1130 sh->dev[i].vec.bv_page = sh->dev[i].page;
4997b72e 1131 bi->bi_vcnt = 1;
91c00924
DW		 1132 bi->bi_io_vec[0].bv_len = STRIPE_SIZE;
1133 bi->bi_io_vec[0].bv_offset = 0;
4f024f37 1134 bi->bi_iter.bi_size = STRIPE_SIZE;
2cd259a7
MD		 1135 bi->bi_write_hint = sh->dev[i].write_hint;
1136 if (!rrdev)
1137 sh->dev[i].write_hint = RWF_WRITE_LIFE_NOT_SET;
37c61ff3
SL		 1138 /*
1139 * If this is discard request, set bi_vcnt 0. We don't
1140 * want to confuse SCSI because SCSI will replace payload
1141 */
796a5cf0 1142 if (op == REQ_OP_DISCARD)
37c61ff3 1143 bi->bi_vcnt = 0;
977df362
N		 1144 if (rrdev)
1145 set_bit(R5_DOUBLE_LOCKED, &sh->dev[i].flags);
e3620a3a
JB		 1146
1147 if (conf->mddev->gendisk)
74d46992 1148 trace_block_bio_remap(bi->bi_disk->queue,
e3620a3a
JB		 1149 bi, disk_devt(conf->mddev->gendisk),
1150 sh->dev[i].sector);
aaf9f12e
SL		 1151 if (should_defer && op_is_write(op))
1152 bio_list_add(&pending_bios, bi);
1153 else
1154 generic_make_request(bi);
977df362
N		 1155 }
1156 if (rrdev) {
9a3e1101
N		 1157 if (s->syncing || s->expanding || s->expanded
1158 || s->replacing)
977df362
N		 1159 md_sync_acct(rrdev->bdev, STRIPE_SECTORS);
1160
1161 set_bit(STRIPE_IO_STARTED, &sh->state);
1162
74d46992 1163 bio_set_dev(rbi, rrdev->bdev);
796a5cf0
MC		 1164 bio_set_op_attrs(rbi, op, op_flags);
1165 BUG_ON(!op_is_write(op));
2f6db2a7
KO		 1166 rbi->bi_end_io = raid5_end_write_request;
1167 rbi->bi_private = sh;
1168
6296b960 1169 pr_debug("%s: for %llu schedule op %d on "
977df362
N		 1170 "replacement disc %d\n",
1171 __func__, (unsigned long long)sh->sector,
1eff9d32 1172 rbi->bi_opf, i);
977df362 1173 atomic_inc(&sh->count);
59fc630b 1174 if (sh != head_sh)
1175 atomic_inc(&head_sh->count);
05616be5 1176 if (use_new_offset(conf, sh))
4f024f37 1177 rbi->bi_iter.bi_sector = (sh->sector
05616be5
N		 1178 + rrdev->new_data_offset);
1179 else
4f024f37 1180 rbi->bi_iter.bi_sector = (sh->sector
05616be5 1181 + rrdev->data_offset);
d592a996
SL		 1182 if (test_bit(R5_SkipCopy, &sh->dev[i].flags))
1183 WARN_ON(test_bit(R5_UPTODATE, &sh->dev[i].flags));
1184 sh->dev[i].rvec.bv_page = sh->dev[i].page;
4997b72e 1185 rbi->bi_vcnt = 1;
977df362
N		 1186 rbi->bi_io_vec[0].bv_len = STRIPE_SIZE;
1187 rbi->bi_io_vec[0].bv_offset = 0;
4f024f37 1188 rbi->bi_iter.bi_size = STRIPE_SIZE;
2cd259a7
MD		 1189 rbi->bi_write_hint = sh->dev[i].write_hint;
1190 sh->dev[i].write_hint = RWF_WRITE_LIFE_NOT_SET;
37c61ff3
SL		 1191 /*
1192 * If this is discard request, set bi_vcnt 0. We don't
1193 * want to confuse SCSI because SCSI will replace payload
1194 */
796a5cf0 1195 if (op == REQ_OP_DISCARD)
37c61ff3 1196 rbi->bi_vcnt = 0;
e3620a3a 1197 if (conf->mddev->gendisk)
74d46992 1198 trace_block_bio_remap(rbi->bi_disk->queue,
e3620a3a
JB		 1199 rbi, disk_devt(conf->mddev->gendisk),
1200 sh->dev[i].sector);
aaf9f12e
SL		 1201 if (should_defer && op_is_write(op))
1202 bio_list_add(&pending_bios, rbi);
1203 else
1204 generic_make_request(rbi);
977df362
N		 1205 }
1206 if (!rdev && !rrdev) {
796a5cf0 1207 if (op_is_write(op))
91c00924 1208 set_bit(STRIPE_DEGRADED, &sh->state);
6296b960 1209 pr_debug("skip op %d on disc %d for sector %llu\n",
1eff9d32 1210 bi->bi_opf, i, (unsigned long long)sh->sector);
91c00924
DW		 1211 clear_bit(R5_LOCKED, &sh->dev[i].flags);
1212 set_bit(STRIPE_HANDLE, &sh->state);
1213 }
59fc630b 1214
1215 if (!head_sh->batch_head)
1216 continue;
1217 sh = list_first_entry(&sh->batch_list, struct stripe_head,
1218 batch_list);
1219 if (sh != head_sh)
1220 goto again;
91c00924 1221 }
aaf9f12e
SL		 1222
1223 if (should_defer && !bio_list_empty(&pending_bios))
1224 defer_issue_bios(conf, head_sh->sector, &pending_bios);
91c00924
DW		 1225}
1226
1227static struct dma_async_tx_descriptor *
d592a996
SL		 1228async_copy_data(int frombio, struct bio *bio, struct page **page,
1229 sector_t sector, struct dma_async_tx_descriptor *tx,
1e6d690b 1230 struct stripe_head *sh, int no_skipcopy)
91c00924 1231{
7988613b
KO		 1232 struct bio_vec bvl;
1233 struct bvec_iter iter;
91c00924 1234 struct page *bio_page;
91c00924 1235 int page_offset;
a08abd8c 1236 struct async_submit_ctl submit;
0403e382 1237 enum async_tx_flags flags = 0;
91c00924 1238
4f024f37
KO		 1239 if (bio->bi_iter.bi_sector >= sector)
1240 page_offset = (signed)(bio->bi_iter.bi_sector - sector) * 512;
91c00924 1241 else
4f024f37 1242 page_offset = (signed)(sector - bio->bi_iter.bi_sector) * -512;
a08abd8c 1243
0403e382
DW		 1244 if (frombio)
1245 flags |= ASYNC_TX_FENCE;
1246 init_async_submit(&submit, flags, tx, NULL, NULL, NULL);
1247
7988613b
KO		 1248 bio_for_each_segment(bvl, bio, iter) {
1249 int len = bvl.bv_len;
91c00924
DW		 1250 int clen;
1251 int b_offset = 0;
1252
1253 if (page_offset < 0) {
1254 b_offset = -page_offset;
1255 page_offset += b_offset;
1256 len -= b_offset;
1257 }
1258
1259 if (len > 0 && page_offset + len > STRIPE_SIZE)
1260 clen = STRIPE_SIZE - page_offset;
1261 else
1262 clen = len;
1263
1264 if (clen > 0) {
7988613b
KO		 1265 b_offset += bvl.bv_offset;
1266 bio_page = bvl.bv_page;
d592a996
SL		 1267 if (frombio) {
1268 if (sh->raid_conf->skip_copy &&
1269 b_offset == 0 && page_offset == 0 &&
1e6d690b
SL		 1270 clen == STRIPE_SIZE &&
1271 !no_skipcopy)
d592a996
SL		 1272 *page = bio_page;
1273 else
1274 tx = async_memcpy(*page, bio_page, page_offset,
a08abd8c 1275 b_offset, clen, &submit);
d592a996
SL		 1276 } else
1277 tx = async_memcpy(bio_page, *page, b_offset,
a08abd8c 1278 page_offset, clen, &submit);
91c00924 1279 }
a08abd8c
DW		 1280 /* chain the operations */
1281 submit.depend_tx = tx;
1282
91c00924
DW		 1283 if (clen < len) /* hit end of page */
1284 break;
1285 page_offset += len;
1286 }
1287
1288 return tx;
1289}
1290
1291static void ops_complete_biofill(void *stripe_head_ref)
1292{
1293 struct stripe_head *sh = stripe_head_ref;
e4d84909 1294 int i;
91c00924 1295
e46b272b 1296 pr_debug("%s: stripe %llu\n", __func__,
91c00924
DW		 1297 (unsigned long long)sh->sector);
1298
1299 /* clear completed biofills */
1300 for (i = sh->disks; i--; ) {
1301 struct r5dev *dev = &sh->dev[i];
91c00924
DW		 1302
1303 /* acknowledge completion of a biofill operation */
e4d84909
DW		 1304 /* and check if we need to reply to a read request,
1305 * new R5_Wantfill requests are held off until
83de75cc 1306 * !STRIPE_BIOFILL_RUN
e4d84909
DW		 1307 */
1308 if (test_and_clear_bit(R5_Wantfill, &dev->flags)) {
91c00924 1309 struct bio *rbi, *rbi2;
91c00924 1310
91c00924
DW		 1311 BUG_ON(!dev->read);
1312 rbi = dev->read;
1313 dev->read = NULL;
4f024f37 1314 while (rbi && rbi->bi_iter.bi_sector <
91c00924
DW		 1315 dev->sector + STRIPE_SECTORS) {
1316 rbi2 = r5_next_bio(rbi, dev->sector);
016c76ac 1317 bio_endio(rbi);
91c00924
DW		 1318 rbi = rbi2;
1319 }
1320 }
1321 }
83de75cc 1322 clear_bit(STRIPE_BIOFILL_RUN, &sh->state);
91c00924 1323
e4d84909 1324 set_bit(STRIPE_HANDLE, &sh->state);
6d036f7d 1325 raid5_release_stripe(sh);
91c00924
DW		 1326}
1327
1328static void ops_run_biofill(struct stripe_head *sh)
1329{
1330 struct dma_async_tx_descriptor *tx = NULL;
a08abd8c 1331 struct async_submit_ctl submit;
91c00924
DW		 1332 int i;
1333
59fc630b 1334 BUG_ON(sh->batch_head);
e46b272b 1335 pr_debug("%s: stripe %llu\n", __func__,
91c00924
DW		 1336 (unsigned long long)sh->sector);
1337
1338 for (i = sh->disks; i--; ) {
1339 struct r5dev *dev = &sh->dev[i];
1340 if (test_bit(R5_Wantfill, &dev->flags)) {
1341 struct bio *rbi;
b17459c0 1342 spin_lock_irq(&sh->stripe_lock);
91c00924
DW		 1343 dev->read = rbi = dev->toread;
1344 dev->toread = NULL;
b17459c0 1345 spin_unlock_irq(&sh->stripe_lock);
4f024f37 1346 while (rbi && rbi->bi_iter.bi_sector <
91c00924 1347 dev->sector + STRIPE_SECTORS) {
d592a996 1348 tx = async_copy_data(0, rbi, &dev->page,
1e6d690b 1349 dev->sector, tx, sh, 0);
91c00924
DW		 1350 rbi = r5_next_bio(rbi, dev->sector);
1351 }
1352 }
1353 }
1354
1355 atomic_inc(&sh->count);
a08abd8c
DW		 1356 init_async_submit(&submit, ASYNC_TX_ACK, tx, ops_complete_biofill, sh, NULL);
1357 async_trigger_callback(&submit);
91c00924
DW		 1358}
1359
4e7d2c0a 1360static void mark_target_uptodate(struct stripe_head *sh, int target)
91c00924 1361{
4e7d2c0a 1362 struct r5dev *tgt;
91c00924 1363
4e7d2c0a
DW		 1364 if (target < 0)
1365 return;
91c00924 1366
4e7d2c0a 1367 tgt = &sh->dev[target];
91c00924
DW		 1368 set_bit(R5_UPTODATE, &tgt->flags);
1369 BUG_ON(!test_bit(R5_Wantcompute, &tgt->flags));
1370 clear_bit(R5_Wantcompute, &tgt->flags);
4e7d2c0a
DW		 1371}
1372
ac6b53b6 1373static void ops_complete_compute(void *stripe_head_ref)
91c00924
DW		 1374{
1375 struct stripe_head *sh = stripe_head_ref;
91c00924 1376
e46b272b 1377 pr_debug("%s: stripe %llu\n", __func__,
91c00924
DW		 1378 (unsigned long long)sh->sector);
1379
ac6b53b6 1380 /* mark the computed target(s) as uptodate */
4e7d2c0a 1381 mark_target_uptodate(sh, sh->ops.target);
ac6b53b6 1382 mark_target_uptodate(sh, sh->ops.target2);
4e7d2c0a 1383
ecc65c9b
DW		 1384 clear_bit(STRIPE_COMPUTE_RUN, &sh->state);
1385 if (sh->check_state == check_state_compute_run)
1386 sh->check_state = check_state_compute_result;
91c00924 1387 set_bit(STRIPE_HANDLE, &sh->state);
6d036f7d 1388 raid5_release_stripe(sh);
91c00924
DW		 1389}
1390
d6f38f31 1391/* return a pointer to the address conversion region of the scribble buffer */
b330e6a4 1392static struct page **to_addr_page(struct raid5_percpu *percpu, int i)
d6f38f31 1393{
b330e6a4 1394 return percpu->scribble + i * percpu->scribble_obj_size;
46d5b785 1395}
1396
1397/* return a pointer to the address conversion region of the scribble buffer */
b330e6a4
KO		 1398static addr_conv_t *to_addr_conv(struct stripe_head *sh,
1399 struct raid5_percpu *percpu, int i)
46d5b785 1400{
b330e6a4 1401 return (void *) (to_addr_page(percpu, i) + sh->disks + 2);
d6f38f31
DW		 1402}
1403
1404static struct dma_async_tx_descriptor *
1405ops_run_compute5(struct stripe_head *sh, struct raid5_percpu *percpu)
91c00924 1406{
91c00924 1407 int disks = sh->disks;
46d5b785 1408 struct page **xor_srcs = to_addr_page(percpu, 0);
91c00924
DW		 1409 int target = sh->ops.target;
1410 struct r5dev *tgt = &sh->dev[target];
1411 struct page *xor_dest = tgt->page;
1412 int count = 0;
1413 struct dma_async_tx_descriptor *tx;
a08abd8c 1414 struct async_submit_ctl submit;
91c00924
DW		 1415 int i;
1416
59fc630b 1417 BUG_ON(sh->batch_head);
1418
91c00924 1419 pr_debug("%s: stripe %llu block: %d\n",
e46b272b 1420 __func__, (unsigned long long)sh->sector, target);
91c00924
DW		 1421 BUG_ON(!test_bit(R5_Wantcompute, &tgt->flags));
1422
1423 for (i = disks; i--; )
1424 if (i != target)
1425 xor_srcs[count++] = sh->dev[i].page;
1426
1427 atomic_inc(&sh->count);
1428
0403e382 1429 init_async_submit(&submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_ZERO_DST, NULL,
46d5b785 1430 ops_complete_compute, sh, to_addr_conv(sh, percpu, 0));
91c00924 1431 if (unlikely(count == 1))
a08abd8c 1432 tx = async_memcpy(xor_dest, xor_srcs[0], 0, 0, STRIPE_SIZE, &submit);
91c00924 1433 else
a08abd8c 1434 tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, &submit);
91c00924 1435
91c00924
DW		 1436 return tx;
1437}
1438
ac6b53b6
DW		 1439/* set_syndrome_sources - populate source buffers for gen_syndrome
1440 * @srcs - (struct page *) array of size sh->disks
1441 * @sh - stripe_head to parse
1442 *
1443 * Populates srcs in proper layout order for the stripe and returns the
1444 * 'count' of sources to be used in a call to async_gen_syndrome. The P
1445 * destination buffer is recorded in srcs[count] and the Q destination
1446 * is recorded in srcs[count+1]].
1447 */
584acdd4
MS		 1448static int set_syndrome_sources(struct page **srcs,
1449 struct stripe_head *sh,
1450 int srctype)
ac6b53b6
DW		 1451{
1452 int disks = sh->disks;
1453 int syndrome_disks = sh->ddf_layout ? disks : (disks - 2);
1454 int d0_idx = raid6_d0(sh);
1455 int count;
1456 int i;
1457
1458 for (i = 0; i < disks; i++)
5dd33c9a 1459 srcs[i] = NULL;
ac6b53b6
DW		 1460
1461 count = 0;
1462 i = d0_idx;
1463 do {
1464 int slot = raid6_idx_to_slot(i, sh, &count, syndrome_disks);
584acdd4 1465 struct r5dev *dev = &sh->dev[i];
ac6b53b6 1466
584acdd4
MS		 1467 if (i == sh->qd_idx || i == sh->pd_idx ||
1468 (srctype == SYNDROME_SRC_ALL) ||
1469 (srctype == SYNDROME_SRC_WANT_DRAIN &&
1e6d690b
SL		 1470 (test_bit(R5_Wantdrain, &dev->flags) ||
1471 test_bit(R5_InJournal, &dev->flags))) ||
584acdd4 1472 (srctype == SYNDROME_SRC_WRITTEN &&
0977762f
SL		 1473 (dev->written ||
1474 test_bit(R5_InJournal, &dev->flags)))) {
1e6d690b
SL		 1475 if (test_bit(R5_InJournal, &dev->flags))
1476 srcs[slot] = sh->dev[i].orig_page;
1477 else
1478 srcs[slot] = sh->dev[i].page;
1479 }
ac6b53b6
DW		 1480 i = raid6_next_disk(i, disks);
1481 } while (i != d0_idx);
ac6b53b6 1482
e4424fee 1483 return syndrome_disks;
ac6b53b6
DW		 1484}
1485
1486static struct dma_async_tx_descriptor *
1487ops_run_compute6_1(struct stripe_head *sh, struct raid5_percpu *percpu)
1488{
1489 int disks = sh->disks;
46d5b785 1490 struct page **blocks = to_addr_page(percpu, 0);
ac6b53b6
DW		 1491 int target;
1492 int qd_idx = sh->qd_idx;
1493 struct dma_async_tx_descriptor *tx;
1494 struct async_submit_ctl submit;
1495 struct r5dev *tgt;
1496 struct page *dest;
1497 int i;
1498 int count;
1499
59fc630b 1500 BUG_ON(sh->batch_head);
ac6b53b6
DW		 1501 if (sh->ops.target < 0)
1502 target = sh->ops.target2;
1503 else if (sh->ops.target2 < 0)
1504 target = sh->ops.target;
91c00924 1505 else
ac6b53b6
DW		 1506 /* we should only have one valid target */
1507 BUG();
1508 BUG_ON(target < 0);
1509 pr_debug("%s: stripe %llu block: %d\n",
1510 __func__, (unsigned long long)sh->sector, target);
1511
1512 tgt = &sh->dev[target];
1513 BUG_ON(!test_bit(R5_Wantcompute, &tgt->flags));
1514 dest = tgt->page;
1515
1516 atomic_inc(&sh->count);
1517
1518 if (target == qd_idx) {
584acdd4 1519 count = set_syndrome_sources(blocks, sh, SYNDROME_SRC_ALL);
ac6b53b6
DW		 1520 blocks[count] = NULL; /* regenerating p is not necessary */
1521 BUG_ON(blocks[count+1] != dest); /* q should already be set */
0403e382
DW		 1522 init_async_submit(&submit, ASYNC_TX_FENCE, NULL,
1523 ops_complete_compute, sh,
46d5b785 1524 to_addr_conv(sh, percpu, 0));
ac6b53b6
DW		 1525 tx = async_gen_syndrome(blocks, 0, count+2, STRIPE_SIZE, &submit);
1526 } else {
1527 /* Compute any data- or p-drive using XOR */
1528 count = 0;
1529 for (i = disks; i-- ; ) {
1530 if (i == target || i == qd_idx)
1531 continue;
1532 blocks[count++] = sh->dev[i].page;
1533 }
1534
0403e382
DW		 1535 init_async_submit(&submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_ZERO_DST,
1536 NULL, ops_complete_compute, sh,
46d5b785 1537 to_addr_conv(sh, percpu, 0));
ac6b53b6
DW		 1538 tx = async_xor(dest, blocks, 0, count, STRIPE_SIZE, &submit);
1539 }
91c00924 1540
91c00924
DW		 1541 return tx;
1542}
1543
ac6b53b6
DW		 1544static struct dma_async_tx_descriptor *
1545ops_run_compute6_2(struct stripe_head *sh, struct raid5_percpu *percpu)
1546{
1547 int i, count, disks = sh->disks;
1548 int syndrome_disks = sh->ddf_layout ? disks : disks-2;
1549 int d0_idx = raid6_d0(sh);
1550 int faila = -1, failb = -1;
1551 int target = sh->ops.target;
1552 int target2 = sh->ops.target2;
1553 struct r5dev *tgt = &sh->dev[target];
1554 struct r5dev *tgt2 = &sh->dev[target2];
1555 struct dma_async_tx_descriptor *tx;
46d5b785 1556 struct page **blocks = to_addr_page(percpu, 0);
ac6b53b6
DW		 1557 struct async_submit_ctl submit;
1558
59fc630b 1559 BUG_ON(sh->batch_head);
ac6b53b6
DW		 1560 pr_debug("%s: stripe %llu block1: %d block2: %d\n",
1561 __func__, (unsigned long long)sh->sector, target, target2);
1562 BUG_ON(target < 0 || target2 < 0);
1563 BUG_ON(!test_bit(R5_Wantcompute, &tgt->flags));
1564 BUG_ON(!test_bit(R5_Wantcompute, &tgt2->flags));
1565
6c910a78 1566 /* we need to open-code set_syndrome_sources to handle the
ac6b53b6
DW		 1567 * slot number conversion for 'faila' and 'failb'
1568 */
1569 for (i = 0; i < disks ; i++)
5dd33c9a 1570 blocks[i] = NULL;
ac6b53b6
DW		 1571 count = 0;
1572 i = d0_idx;
1573 do {
1574 int slot = raid6_idx_to_slot(i, sh, &count, syndrome_disks);
1575
1576 blocks[slot] = sh->dev[i].page;
1577
1578 if (i == target)
1579 faila = slot;
1580 if (i == target2)
1581 failb = slot;
1582 i = raid6_next_disk(i, disks);
1583 } while (i != d0_idx);
ac6b53b6
DW		 1584
1585 BUG_ON(faila == failb);
1586 if (failb < faila)
1587 swap(faila, failb);
1588 pr_debug("%s: stripe: %llu faila: %d failb: %d\n",
1589 __func__, (unsigned long long)sh->sector, faila, failb);
1590
1591 atomic_inc(&sh->count);
1592
1593 if (failb == syndrome_disks+1) {
1594 /* Q disk is one of the missing disks */
1595 if (faila == syndrome_disks) {
1596 /* Missing P+Q, just recompute */
0403e382
DW		 1597 init_async_submit(&submit, ASYNC_TX_FENCE, NULL,
1598 ops_complete_compute, sh,
46d5b785 1599 to_addr_conv(sh, percpu, 0));
e4424fee 1600 return async_gen_syndrome(blocks, 0, syndrome_disks+2,
ac6b53b6
DW		 1601 STRIPE_SIZE, &submit);
1602 } else {
1603 struct page *dest;
1604 int data_target;
1605 int qd_idx = sh->qd_idx;
1606
1607 /* Missing D+Q: recompute D from P, then recompute Q */
1608 if (target == qd_idx)
1609 data_target = target2;
1610 else
1611 data_target = target;
1612
1613 count = 0;
1614 for (i = disks; i-- ; ) {
1615 if (i == data_target || i == qd_idx)
1616 continue;
1617 blocks[count++] = sh->dev[i].page;
1618 }
1619 dest = sh->dev[data_target].page;
0403e382
DW		 1620 init_async_submit(&submit,
1621 ASYNC_TX_FENCE|ASYNC_TX_XOR_ZERO_DST,
1622 NULL, NULL, NULL,
46d5b785 1623 to_addr_conv(sh, percpu, 0));
ac6b53b6
DW		 1624 tx = async_xor(dest, blocks, 0, count, STRIPE_SIZE,
1625 &submit);
1626
584acdd4 1627 count = set_syndrome_sources(blocks, sh, SYNDROME_SRC_ALL);
0403e382
DW		 1628 init_async_submit(&submit, ASYNC_TX_FENCE, tx,
1629 ops_complete_compute, sh,
46d5b785 1630 to_addr_conv(sh, percpu, 0));
ac6b53b6
DW		 1631 return async_gen_syndrome(blocks, 0, count+2,
1632 STRIPE_SIZE, &submit);
1633 }
ac6b53b6 1634 } else {
6c910a78
DW		 1635 init_async_submit(&submit, ASYNC_TX_FENCE, NULL,
1636 ops_complete_compute, sh,
46d5b785 1637 to_addr_conv(sh, percpu, 0));
6c910a78
DW		 1638 if (failb == syndrome_disks) {
1639 /* We're missing D+P. */
1640 return async_raid6_datap_recov(syndrome_disks+2,
1641 STRIPE_SIZE, faila,
1642 blocks, &submit);
1643 } else {
1644 /* We're missing D+D. */
1645 return async_raid6_2data_recov(syndrome_disks+2,
1646 STRIPE_SIZE, faila, failb,
1647 blocks, &submit);
1648 }
ac6b53b6
DW		 1649 }
1650}
1651
91c00924
DW		 1652static void ops_complete_prexor(void *stripe_head_ref)
1653{
1654 struct stripe_head *sh = stripe_head_ref;
1655
e46b272b 1656 pr_debug("%s: stripe %llu\n", __func__,
91c00924 1657 (unsigned long long)sh->sector);
1e6d690b
SL		 1658
1659 if (r5c_is_writeback(sh->raid_conf->log))
1660 /*
1661 * raid5-cache write back uses orig_page during prexor.
1662 * After prexor, it is time to free orig_page
1663 */
1664 r5c_release_extra_page(sh);
91c00924
DW		 1665}
1666
1667static struct dma_async_tx_descriptor *
584acdd4
MS		 1668ops_run_prexor5(struct stripe_head *sh, struct raid5_percpu *percpu,
1669 struct dma_async_tx_descriptor *tx)
91c00924 1670{
91c00924 1671 int disks = sh->disks;
46d5b785 1672 struct page **xor_srcs = to_addr_page(percpu, 0);
91c00924 1673 int count = 0, pd_idx = sh->pd_idx, i;
a08abd8c 1674 struct async_submit_ctl submit;
91c00924
DW		 1675
1676 /* existing parity data subtracted */
1677 struct page *xor_dest = xor_srcs[count++] = sh->dev[pd_idx].page;
1678
59fc630b 1679 BUG_ON(sh->batch_head);
e46b272b 1680 pr_debug("%s: stripe %llu\n", __func__,
91c00924
DW		 1681 (unsigned long long)sh->sector);
1682
1683 for (i = disks; i--; ) {
1684 struct r5dev *dev = &sh->dev[i];
1685 /* Only process blocks that are known to be uptodate */
1e6d690b
SL		 1686 if (test_bit(R5_InJournal, &dev->flags))
1687 xor_srcs[count++] = dev->orig_page;
1688 else if (test_bit(R5_Wantdrain, &dev->flags))
91c00924
DW		 1689 xor_srcs[count++] = dev->page;
1690 }
1691
0403e382 1692 init_async_submit(&submit, ASYNC_TX_FENCE|ASYNC_TX_XOR_DROP_DST, tx,
46d5b785 1693 ops_complete_prexor, sh, to_addr_conv(sh, percpu, 0));
a08abd8c 1694 tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, &submit);
91c00924
DW		 1695
1696 return tx;
1697}
1698
584acdd4
MS		 1699static struct dma_async_tx_descriptor *
1700ops_run_prexor6(struct stripe_head *sh, struct raid5_percpu *percpu,
1701 struct dma_async_tx_descriptor *tx)
1702{
1703 struct page **blocks = to_addr_page(percpu, 0);
1704 int count;
1705 struct async_submit_ctl submit;
1706
1707 pr_debug("%s: stripe %llu\n", __func__,
1708 (unsigned long long)sh->sector);
1709
1710 count = set_syndrome_sources(blocks, sh, SYNDROME_SRC_WANT_DRAIN);
1711
1712 init_async_submit(&submit, ASYNC_TX_FENCE|ASYNC_TX_PQ_XOR_DST, tx,
1713 ops_complete_prexor, sh, to_addr_conv(sh, percpu, 0));
1714 tx = async_gen_syndrome(blocks, 0, count+2, STRIPE_SIZE, &submit);
1715
1716 return tx;
1717}
1718
91c00924 1719static struct dma_async_tx_descriptor *
d8ee0728 1720ops_run_biodrain(struct stripe_head *sh, struct dma_async_tx_descriptor *tx)
91c00924 1721{
1e6d690b 1722 struct r5conf *conf = sh->raid_conf;
91c00924 1723 int disks = sh->disks;
d8ee0728 1724 int i;
59fc630b 1725 struct stripe_head *head_sh = sh;
91c00924 1726
e46b272b 1727 pr_debug("%s: stripe %llu\n", __func__,
91c00924
DW		 1728 (unsigned long long)sh->sector);
1729
1730 for (i = disks; i--; ) {
59fc630b 1731 struct r5dev *dev;
91c00924 1732 struct bio *chosen;
91c00924 1733
59fc630b 1734 sh = head_sh;
1735 if (test_and_clear_bit(R5_Wantdrain, &head_sh->dev[i].flags)) {
91c00924
DW		 1736 struct bio *wbi;
1737
59fc630b 1738again:
1739 dev = &sh->dev[i];
1e6d690b
SL		 1740 /*
1741 * clear R5_InJournal, so when rewriting a page in
1742 * journal, it is not skipped by r5l_log_stripe()
1743 */
1744 clear_bit(R5_InJournal, &dev->flags);
b17459c0 1745 spin_lock_irq(&sh->stripe_lock);
91c00924
DW		 1746 chosen = dev->towrite;
1747 dev->towrite = NULL;
7a87f434 1748 sh->overwrite_disks = 0;
91c00924
DW		 1749 BUG_ON(dev->written);
1750 wbi = dev->written = chosen;
b17459c0 1751 spin_unlock_irq(&sh->stripe_lock);
d592a996 1752 WARN_ON(dev->page != dev->orig_page);
91c00924 1753
4f024f37 1754 while (wbi && wbi->bi_iter.bi_sector <
91c00924 1755 dev->sector + STRIPE_SECTORS) {
1eff9d32 1756 if (wbi->bi_opf & REQ_FUA)
e9c7469b 1757 set_bit(R5_WantFUA, &dev->flags);
1eff9d32 1758 if (wbi->bi_opf & REQ_SYNC)
bc0934f0 1759 set_bit(R5_SyncIO, &dev->flags);
796a5cf0 1760 if (bio_op(wbi) == REQ_OP_DISCARD)
620125f2 1761 set_bit(R5_Discard, &dev->flags);
d592a996
SL		 1762 else {
1763 tx = async_copy_data(1, wbi, &dev->page,
1e6d690b
SL		 1764 dev->sector, tx, sh,
1765 r5c_is_writeback(conf->log));
1766 if (dev->page != dev->orig_page &&
1767 !r5c_is_writeback(conf->log)) {
d592a996
SL		 1768 set_bit(R5_SkipCopy, &dev->flags);
1769 clear_bit(R5_UPTODATE, &dev->flags);
1770 clear_bit(R5_OVERWRITE, &dev->flags);
1771 }
1772 }
91c00924
DW		 1773 wbi = r5_next_bio(wbi, dev->sector);
1774 }
59fc630b 1775
1776 if (head_sh->batch_head) {
1777 sh = list_first_entry(&sh->batch_list,
1778 struct stripe_head,
1779 batch_list);
1780 if (sh == head_sh)
1781 continue;
1782 goto again;
1783 }
91c00924
DW		 1784 }
1785 }
1786
1787 return tx;
1788}
1789
ac6b53b6 1790static void ops_complete_reconstruct(void *stripe_head_ref)
91c00924
DW		 1791{
1792 struct stripe_head *sh = stripe_head_ref;
ac6b53b6
DW		 1793 int disks = sh->disks;
1794 int pd_idx = sh->pd_idx;
1795 int qd_idx = sh->qd_idx;
1796 int i;
9e444768 1797 bool fua = false, sync = false, discard = false;
91c00924 1798
e46b272b 1799 pr_debug("%s: stripe %llu\n", __func__,
91c00924
DW		 1800 (unsigned long long)sh->sector);
1801
bc0934f0 1802 for (i = disks; i--; ) {
e9c7469b 1803 fua |= test_bit(R5_WantFUA, &sh->dev[i].flags);
bc0934f0 1804 sync |= test_bit(R5_SyncIO, &sh->dev[i].flags);
9e444768 1805 discard |= test_bit(R5_Discard, &sh->dev[i].flags);
bc0934f0 1806 }
e9c7469b 1807
91c00924
DW		 1808 for (i = disks; i--; ) {
1809 struct r5dev *dev = &sh->dev[i];
ac6b53b6 1810
e9c7469b 1811 if (dev->written || i == pd_idx || i == qd_idx) {
235b6003 1812 if (!discard && !test_bit(R5_SkipCopy, &dev->flags)) {
9e444768 1813 set_bit(R5_UPTODATE, &dev->flags);
235b6003
N		 1814 if (test_bit(STRIPE_EXPAND_READY, &sh->state))
1815 set_bit(R5_Expanded, &dev->flags);
1816 }
e9c7469b
TH		 1817 if (fua)
1818 set_bit(R5_WantFUA, &dev->flags);
bc0934f0
SL		 1819 if (sync)
1820 set_bit(R5_SyncIO, &dev->flags);
e9c7469b 1821 }
91c00924
DW		 1822 }
1823
d8ee0728
DW		 1824 if (sh->reconstruct_state == reconstruct_state_drain_run)
1825 sh->reconstruct_state = reconstruct_state_drain_result;
1826 else if (sh->reconstruct_state == reconstruct_state_prexor_drain_run)
1827 sh->reconstruct_state = reconstruct_state_prexor_drain_result;
1828 else {
1829 BUG_ON(sh->reconstruct_state != reconstruct_state_run);
1830 sh->reconstruct_state = reconstruct_state_result;
1831 }
91c00924
DW		 1832
1833 set_bit(STRIPE_HANDLE, &sh->state);
6d036f7d 1834 raid5_release_stripe(sh);
91c00924
DW		 1835}
1836
1837static void
ac6b53b6
DW		 1838ops_run_reconstruct5(struct stripe_head *sh, struct raid5_percpu *percpu,
1839 struct dma_async_tx_descriptor *tx)
91c00924 1840{
91c00924 1841 int disks = sh->disks;
59fc630b 1842 struct page **xor_srcs;
a08abd8c 1843 struct async_submit_ctl submit;
59fc630b 1844 int count, pd_idx = sh->pd_idx, i;
91c00924 1845 struct page *xor_dest;
d8ee0728 1846 int prexor = 0;
91c00924 1847 unsigned long flags;
59fc630b 1848 int j = 0;
1849 struct stripe_head *head_sh = sh;
1850 int last_stripe;
91c00924 1851
e46b272b 1852 pr_debug("%s: stripe %llu\n", __func__,
91c00924
DW		 1853 (unsigned long long)sh->sector);
1854
620125f2
SL		 1855 for (i = 0; i < sh->disks; i++) {
1856 if (pd_idx == i)
1857 continue;
1858 if (!test_bit(R5_Discard, &sh->dev[i].flags))
1859 break;
1860 }
1861 if (i >= sh->disks) {
1862 atomic_inc(&sh->count);
620125f2
SL		 1863 set_bit(R5_Discard, &sh->dev[pd_idx].flags);
1864 ops_complete_reconstruct(sh);
1865 return;
1866 }
59fc630b 1867again:
1868 count = 0;
1869 xor_srcs = to_addr_page(percpu, j);
91c00924
DW		 1870 /* check if prexor is active which means only process blocks
1871 * that are part of a read-modify-write (written)
1872 */
59fc630b 1873 if (head_sh->reconstruct_state == reconstruct_state_prexor_drain_run) {
d8ee0728 1874 prexor = 1;
91c00924
DW		 1875 xor_dest = xor_srcs[count++] = sh->dev[pd_idx].page;
1876 for (i = disks; i--; ) {
1877 struct r5dev *dev = &sh->dev[i];
1e6d690b
SL		 1878 if (head_sh->dev[i].written ||
1879 test_bit(R5_InJournal, &head_sh->dev[i].flags))
91c00924
DW		 1880 xor_srcs[count++] = dev->page;
1881 }
1882 } else {
1883 xor_dest = sh->dev[pd_idx].page;
1884 for (i = disks; i--; ) {
1885 struct r5dev *dev = &sh->dev[i];
1886 if (i != pd_idx)
1887 xor_srcs[count++] = dev->page;
1888 }
1889 }
1890
91c00924
DW		 1891 /* 1/ if we prexor'd then the dest is reused as a source
1892 * 2/ if we did not prexor then we are redoing the parity
1893 * set ASYNC_TX_XOR_DROP_DST and ASYNC_TX_XOR_ZERO_DST
1894 * for the synchronous xor case
1895 */
59fc630b 1896 last_stripe = !head_sh->batch_head ||
1897 list_first_entry(&sh->batch_list,
1898 struct stripe_head, batch_list) == head_sh;
1899 if (last_stripe) {
1900 flags = ASYNC_TX_ACK |
1901 (prexor ? ASYNC_TX_XOR_DROP_DST : ASYNC_TX_XOR_ZERO_DST);
1902
1903 atomic_inc(&head_sh->count);
1904 init_async_submit(&submit, flags, tx, ops_complete_reconstruct, head_sh,
1905 to_addr_conv(sh, percpu, j));
1906 } else {
1907 flags = prexor ? ASYNC_TX_XOR_DROP_DST : ASYNC_TX_XOR_ZERO_DST;
1908 init_async_submit(&submit, flags, tx, NULL, NULL,
1909 to_addr_conv(sh, percpu, j));
1910 }
91c00924 1911
a08abd8c
DW		 1912 if (unlikely(count == 1))
1913 tx = async_memcpy(xor_dest, xor_srcs[0], 0, 0, STRIPE_SIZE, &submit);
1914 else
1915 tx = async_xor(xor_dest, xor_srcs, 0, count, STRIPE_SIZE, &submit);
59fc630b 1916 if (!last_stripe) {
1917 j++;
1918 sh = list_first_entry(&sh->batch_list, struct stripe_head,
1919 batch_list);
1920 goto again;
1921 }
91c00924
DW		 1922}
1923
ac6b53b6
DW		 1924static void
1925ops_run_reconstruct6(struct stripe_head *sh, struct raid5_percpu *percpu,
1926 struct dma_async_tx_descriptor *tx)
1927{
1928 struct async_submit_ctl submit;
59fc630b 1929 struct page **blocks;
1930 int count, i, j = 0;
1931 struct stripe_head *head_sh = sh;
1932 int last_stripe;
584acdd4
MS		 1933 int synflags;
1934 unsigned long txflags;
ac6b53b6
DW		 1935
1936 pr_debug("%s: stripe %llu\n", __func__, (unsigned long long)sh->sector);
1937
620125f2
SL		 1938 for (i = 0; i < sh->disks; i++) {
1939 if (sh->pd_idx == i || sh->qd_idx == i)
1940 continue;
1941 if (!test_bit(R5_Discard, &sh->dev[i].flags))
1942 break;
1943 }
1944 if (i >= sh->disks) {
1945 atomic_inc(&sh->count);
620125f2
SL		 1946 set_bit(R5_Discard, &sh->dev[sh->pd_idx].flags);
1947 set_bit(R5_Discard, &sh->dev[sh->qd_idx].flags);
1948 ops_complete_reconstruct(sh);
1949 return;
1950 }
1951
59fc630b 1952again:
1953 blocks = to_addr_page(percpu, j);
584acdd4
MS		 1954
1955 if (sh->reconstruct_state == reconstruct_state_prexor_drain_run) {
1956 synflags = SYNDROME_SRC_WRITTEN;
1957 txflags = ASYNC_TX_ACK | ASYNC_TX_PQ_XOR_DST;
1958 } else {
1959 synflags = SYNDROME_SRC_ALL;
1960 txflags = ASYNC_TX_ACK;
1961 }
1962
1963 count = set_syndrome_sources(blocks, sh, synflags);
59fc630b 1964 last_stripe = !head_sh->batch_head ||
1965 list_first_entry(&sh->batch_list,
1966 struct stripe_head, batch_list) == head_sh;
1967
1968 if (last_stripe) {
1969 atomic_inc(&head_sh->count);
584acdd4 1970 init_async_submit(&submit, txflags, tx, ops_complete_reconstruct,
59fc630b 1971 head_sh, to_addr_conv(sh, percpu, j));
1972 } else
1973 init_async_submit(&submit, 0, tx, NULL, NULL,
1974 to_addr_conv(sh, percpu, j));
48769695 1975 tx = async_gen_syndrome(blocks, 0, count+2, STRIPE_SIZE, &submit);
59fc630b 1976 if (!last_stripe) {
1977 j++;
1978 sh = list_first_entry(&sh->batch_list, struct stripe_head,
1979 batch_list);
1980 goto again;
1981 }
91c00924
DW		 1982}
1983
1984static void ops_complete_check(void *stripe_head_ref)
1985{
1986 struct stripe_head *sh = stripe_head_ref;
91c00924 1987
e46b272b 1988 pr_debug("%s: stripe %llu\n", __func__,
91c00924
DW		 1989 (unsigned long long)sh->sector);
1990
ecc65c9b 1991 sh->check_state = check_state_check_result;
91c00924 1992 set_bit(STRIPE_HANDLE, &sh->state);
6d036f7d 1993 raid5_release_stripe(sh);
91c00924
DW		 1994}
1995
ac6b53b6 1996static void ops_run_check_p(struct stripe_head *sh, struct raid5_percpu *percpu)
91c00924 1997{
91c00924 1998 int disks = sh->disks;
ac6b53b6
DW		 1999 int pd_idx = sh->pd_idx;
2000 int qd_idx = sh->qd_idx;
2001 struct page *xor_dest;
46d5b785 2002 struct page **xor_srcs = to_addr_page(percpu, 0);
91c00924 2003 struct dma_async_tx_descriptor *tx;
a08abd8c 2004 struct async_submit_ctl submit;
ac6b53b6
DW		 2005 int count;
2006 int i;
91c00924 2007
e46b272b 2008 pr_debug("%s: stripe %llu\n", __func__,
91c00924
DW		 2009 (unsigned long long)sh->sector);
2010
59fc630b 2011 BUG_ON(sh->batch_head);
ac6b53b6
DW		 2012 count = 0;
2013 xor_dest = sh->dev[pd_idx].page;
2014 xor_srcs[count++] = xor_dest;
91c00924 2015 for (i = disks; i--; ) {
ac6b53b6
DW		 2016 if (i == pd_idx || i == qd_idx)
2017 continue;
2018 xor_srcs[count++] = sh->dev[i].page;
91c00924
DW		 2019 }
2020
d6f38f31 2021 init_async_submit(&submit, 0, NULL, NULL, NULL,
46d5b785 2022 to_addr_conv(sh, percpu, 0));
099f53cb 2023 tx = async_xor_val(xor_dest, xor_srcs, 0, count, STRIPE_SIZE,
a08abd8c 2024 &sh->ops.zero_sum_result, &submit);
91c00924 2025
91c00924 2026 atomic_inc(&sh->count);
a08abd8c
DW		 2027 init_async_submit(&submit, ASYNC_TX_ACK, tx, ops_complete_check, sh, NULL);
2028 tx = async_trigger_callback(&submit);
91c00924
DW		 2029}
2030
ac6b53b6
DW		 2031static void ops_run_check_pq(struct stripe_head *sh, struct raid5_percpu *percpu, int checkp)
2032{
46d5b785 2033 struct page **srcs = to_addr_page(percpu, 0);
ac6b53b6
DW		 2034 struct async_submit_ctl submit;
2035 int count;
2036
2037 pr_debug("%s: stripe %llu checkp: %d\n", __func__,
2038 (unsigned long long)sh->sector, checkp);
2039
59fc630b 2040 BUG_ON(sh->batch_head);
584acdd4 2041 count = set_syndrome_sources(srcs, sh, SYNDROME_SRC_ALL);
ac6b53b6
DW		 2042 if (!checkp)
2043 srcs[count] = NULL;
91c00924 2044
91c00924 2045 atomic_inc(&sh->count);
ac6b53b6 2046 init_async_submit(&submit, ASYNC_TX_ACK, NULL, ops_complete_check,
46d5b785 2047 sh, to_addr_conv(sh, percpu, 0));
ac6b53b6
DW		 2048 async_syndrome_val(srcs, 0, count+2, STRIPE_SIZE,
2049 &sh->ops.zero_sum_result, percpu->spare_page, &submit);
91c00924
DW		 2050}
2051
51acbcec 2052static void raid_run_ops(struct stripe_head *sh, unsigned long ops_request)
91c00924
DW		 2053{
2054 int overlap_clear = 0, i, disks = sh->disks;
2055 struct dma_async_tx_descriptor *tx = NULL;
d1688a6d 2056 struct r5conf *conf = sh->raid_conf;
ac6b53b6 2057 int level = conf->level;
d6f38f31
DW		 2058 struct raid5_percpu *percpu;
2059 unsigned long cpu;
91c00924 2060
d6f38f31
DW		 2061 cpu = get_cpu();
2062 percpu = per_cpu_ptr(conf->percpu, cpu);
83de75cc 2063 if (test_bit(STRIPE_OP_BIOFILL, &ops_request)) {
91c00924
DW		 2064 ops_run_biofill(sh);
2065 overlap_clear++;
2066 }
2067
7b3a871e 2068 if (test_bit(STRIPE_OP_COMPUTE_BLK, &ops_request)) {
ac6b53b6
DW		 2069 if (level < 6)
2070 tx = ops_run_compute5(sh, percpu);
2071 else {
2072 if (sh->ops.target2 < 0 || sh->ops.target < 0)
2073 tx = ops_run_compute6_1(sh, percpu);
2074 else
2075 tx = ops_run_compute6_2(sh, percpu);
2076 }
2077 /* terminate the chain if reconstruct is not set to be run */
2078 if (tx && !test_bit(STRIPE_OP_RECONSTRUCT, &ops_request))
7b3a871e
DW		 2079 async_tx_ack(tx);
2080 }
91c00924 2081
584acdd4
MS		 2082 if (test_bit(STRIPE_OP_PREXOR, &ops_request)) {
2083 if (level < 6)
2084 tx = ops_run_prexor5(sh, percpu, tx);
2085 else
2086 tx = ops_run_prexor6(sh, percpu, tx);
2087 }
91c00924 2088
ae1713e2
AP		 2089 if (test_bit(STRIPE_OP_PARTIAL_PARITY, &ops_request))
2090 tx = ops_run_partial_parity(sh, percpu, tx);
2091
600aa109 2092 if (test_bit(STRIPE_OP_BIODRAIN, &ops_request)) {
d8ee0728 2093 tx = ops_run_biodrain(sh, tx);
91c00924
DW		 2094 overlap_clear++;
2095 }
2096
ac6b53b6
DW		 2097 if (test_bit(STRIPE_OP_RECONSTRUCT, &ops_request)) {
2098 if (level < 6)
2099 ops_run_reconstruct5(sh, percpu, tx);
2100 else
2101 ops_run_reconstruct6(sh, percpu, tx);
2102 }
91c00924 2103
ac6b53b6
DW		 2104 if (test_bit(STRIPE_OP_CHECK, &ops_request)) {
2105 if (sh->check_state == check_state_run)
2106 ops_run_check_p(sh, percpu);
2107 else if (sh->check_state == check_state_run_q)
2108 ops_run_check_pq(sh, percpu, 0);
2109 else if (sh->check_state == check_state_run_pq)
2110 ops_run_check_pq(sh, percpu, 1);
2111 else
2112 BUG();
2113 }
91c00924 2114
59fc630b 2115 if (overlap_clear && !sh->batch_head)
91c00924
DW		 2116 for (i = disks; i--; ) {
2117 struct r5dev *dev = &sh->dev[i];
2118 if (test_and_clear_bit(R5_Overlap, &dev->flags))
2119 wake_up(&sh->raid_conf->wait_for_overlap);
2120 }
d6f38f31 2121 put_cpu();
91c00924
DW		 2122}
2123
845b9e22
AP		 2124static void free_stripe(struct kmem_cache *sc, struct stripe_head *sh)
2125{
2126 if (sh->ppl_page)
2127 __free_page(sh->ppl_page);
2128 kmem_cache_free(sc, sh);
2129}
2130
5f9d1fde 2131static struct stripe_head *alloc_stripe(struct kmem_cache *sc, gfp_t gfp,
845b9e22 2132 int disks, struct r5conf *conf)
f18c1a35
N		 2133{
2134 struct stripe_head *sh;
5f9d1fde 2135 int i;
f18c1a35
N		 2136
2137 sh = kmem_cache_zalloc(sc, gfp);
2138 if (sh) {
2139 spin_lock_init(&sh->stripe_lock);
2140 spin_lock_init(&sh->batch_lock);
2141 INIT_LIST_HEAD(&sh->batch_list);
2142 INIT_LIST_HEAD(&sh->lru);
a39f7afd 2143 INIT_LIST_HEAD(&sh->r5c);
d7bd398e 2144 INIT_LIST_HEAD(&sh->log_list);
f18c1a35 2145 atomic_set(&sh->count, 1);
845b9e22 2146 sh->raid_conf = conf;
a39f7afd 2147 sh->log_start = MaxSector;
5f9d1fde
SL		 2148 for (i = 0; i < disks; i++) {
2149 struct r5dev *dev = &sh->dev[i];
2150
3a83f467
ML		 2151 bio_init(&dev->req, &dev->vec, 1);
2152 bio_init(&dev->rreq, &dev->rvec, 1);
5f9d1fde 2153 }
845b9e22
AP		 2154
2155 if (raid5_has_ppl(conf)) {
2156 sh->ppl_page = alloc_page(gfp);
2157 if (!sh->ppl_page) {
2158 free_stripe(sc, sh);
2159 sh = NULL;
2160 }
2161 }
f18c1a35
N		 2162 }
2163 return sh;
2164}
486f0644 2165static int grow_one_stripe(struct r5conf *conf, gfp_t gfp)
1da177e4
LT		 2166{
2167 struct stripe_head *sh;
f18c1a35 2168
845b9e22 2169 sh = alloc_stripe(conf->slab_cache, gfp, conf->pool_size, conf);
3f294f4f
N		 2170 if (!sh)
2171 return 0;
6ce32846 2172
a9683a79 2173 if (grow_buffers(sh, gfp)) {
e4e11e38 2174 shrink_buffers(sh);
845b9e22 2175 free_stripe(conf->slab_cache, sh);
3f294f4f
N		 2176 return 0;
2177 }
486f0644
N		 2178 sh->hash_lock_index =
2179 conf->max_nr_stripes % NR_STRIPE_HASH_LOCKS;
3f294f4f 2180 /* we just created an active stripe so... */
3f294f4f 2181 atomic_inc(&conf->active_stripes);
59fc630b 2182
6d036f7d 2183 raid5_release_stripe(sh);
486f0644 2184 conf->max_nr_stripes++;
3f294f4f
N		 2185 return 1;
2186}
2187
d1688a6d 2188static int grow_stripes(struct r5conf *conf, int num)
3f294f4f 2189{
e18b890b 2190 struct kmem_cache *sc;
53b8d89d 2191 size_t namelen = sizeof(conf->cache_name[0]);
5e5e3e78 2192 int devs = max(conf->raid_disks, conf->previous_raid_disks);
1da177e4 2193
f4be6b43 2194 if (conf->mddev->gendisk)
53b8d89d 2195 snprintf(conf->cache_name[0], namelen,
f4be6b43
N		 2196 "raid%d-%s", conf->level, mdname(conf->mddev));
2197 else
53b8d89d 2198 snprintf(conf->cache_name[0], namelen,
f4be6b43 2199 "raid%d-%p", conf->level, conf->mddev);
53b8d89d 2200 snprintf(conf->cache_name[1], namelen, "%.27s-alt", conf->cache_name[0]);
f4be6b43 2201
ad01c9e3
N		 2202 conf->active_name = 0;
2203 sc = kmem_cache_create(conf->cache_name[conf->active_name],
1da177e4 2204 sizeof(struct stripe_head)+(devs-1)*sizeof(struct r5dev),
20c2df83 2205 0, 0, NULL);
1da177e4
LT		 2206 if (!sc)
2207 return 1;
2208 conf->slab_cache = sc;
ad01c9e3 2209 conf->pool_size = devs;
486f0644
N		 2210 while (num--)
2211 if (!grow_one_stripe(conf, GFP_KERNEL))
1da177e4 2212 return 1;
486f0644 2213
1da177e4
LT		 2214 return 0;
2215}
29269553 2216
d6f38f31
DW		 2217/**
2218 * scribble_len - return the required size of the scribble region
2219 * @num - total number of disks in the array
2220 *
2221 * The size must be enough to contain:
2222 * 1/ a struct page pointer for each device in the array +2
2223 * 2/ room to convert each entry in (1) to its corresponding dma
2224 * (dma_map_page()) or page (page_address()) address.
2225 *
2226 * Note: the +2 is for the destination buffers of the ddf/raid6 case where we
2227 * calculate over all devices (not just the data blocks), using zeros in place
2228 * of the P and Q blocks.
2229 */
b330e6a4
KO		 2230static int scribble_alloc(struct raid5_percpu *percpu,
2231 int num, int cnt, gfp_t flags)
d6f38f31 2232{
b330e6a4
KO		 2233 size_t obj_size =
2234 sizeof(struct page *) * (num+2) +
2235 sizeof(addr_conv_t) * (num+2);
2236 void *scribble;
d6f38f31 2237
b330e6a4
KO		 2238 scribble = kvmalloc_array(cnt, obj_size, flags);
2239 if (!scribble)
2240 return -ENOMEM;
2241
2242 kvfree(percpu->scribble);
2243
2244 percpu->scribble = scribble;
2245 percpu->scribble_obj_size = obj_size;
2246 return 0;
d6f38f31
DW		 2247}
2248
738a2738
N		 2249static int resize_chunks(struct r5conf *conf, int new_disks, int new_sectors)
2250{
2251 unsigned long cpu;
2252 int err = 0;
2253
27a353c0
SL		 2254 /*
2255 * Never shrink. And mddev_suspend() could deadlock if this is called
2256 * from raid5d. In that case, scribble_disks and scribble_sectors
2257 * should equal to new_disks and new_sectors
2258 */
2259 if (conf->scribble_disks >= new_disks &&
2260 conf->scribble_sectors >= new_sectors)
2261 return 0;
738a2738
N		 2262 mddev_suspend(conf->mddev);
2263 get_online_cpus();
b330e6a4 2264
738a2738
N		 2265 for_each_present_cpu(cpu) {
2266 struct raid5_percpu *percpu;
738a2738
N		 2267
2268 percpu = per_cpu_ptr(conf->percpu, cpu);
b330e6a4
KO		 2269 err = scribble_alloc(percpu, new_disks,
2270 new_sectors / STRIPE_SECTORS,
2271 GFP_NOIO);
2272 if (err)
738a2738 2273 break;
738a2738 2274 }
b330e6a4 2275
738a2738
N		 2276 put_online_cpus();
2277 mddev_resume(conf->mddev);
27a353c0
SL		 2278 if (!err) {
2279 conf->scribble_disks = new_disks;
2280 conf->scribble_sectors = new_sectors;
2281 }
738a2738
N		 2282 return err;
2283}
2284
d1688a6d 2285static int resize_stripes(struct r5conf *conf, int newsize)
ad01c9e3
N		 2286{
2287 /* Make all the stripes able to hold 'newsize' devices.
2288 * New slots in each stripe get 'page' set to a new page.
2289 *
2290 * This happens in stages:
2291 * 1/ create a new kmem_cache and allocate the required number of
2292 * stripe_heads.
83f0d77a 2293 * 2/ gather all the old stripe_heads and transfer the pages across
ad01c9e3
N		 2294 * to the new stripe_heads. This will have the side effect of
2295 * freezing the array as once all stripe_heads have been collected,
2296 * no IO will be possible. Old stripe heads are freed once their
2297 * pages have been transferred over, and the old kmem_cache is
2298 * freed when all stripes are done.
2299 * 3/ reallocate conf->disks to be suitable bigger. If this fails,
3560741e 2300 * we simple return a failure status - no need to clean anything up.
ad01c9e3
N		 2301 * 4/ allocate new pages for the new slots in the new stripe_heads.
2302 * If this fails, we don't bother trying the shrink the
2303 * stripe_heads down again, we just leave them as they are.
2304 * As each stripe_head is processed the new one is released into
2305 * active service.
2306 *
2307 * Once step2 is started, we cannot afford to wait for a write,
2308 * so we use GFP_NOIO allocations.
2309 */
2310 struct stripe_head *osh, *nsh;
2311 LIST_HEAD(newstripes);
2312 struct disk_info *ndisks;
2214c260 2313 int err = 0;
e18b890b 2314 struct kmem_cache *sc;
ad01c9e3 2315 int i;
566c09c5 2316 int hash, cnt;
ad01c9e3 2317
2214c260 2318 md_allow_write(conf->mddev);
2a2275d6 2319
ad01c9e3
N		 2320 /* Step 1 */
2321 sc = kmem_cache_create(conf->cache_name[1-conf->active_name],
2322 sizeof(struct stripe_head)+(newsize-1)*sizeof(struct r5dev),
20c2df83 2323 0, 0, NULL);
ad01c9e3
N		 2324 if (!sc)
2325 return -ENOMEM;
2326
2d5b569b
N		 2327 /* Need to ensure auto-resizing doesn't interfere */
2328 mutex_lock(&conf->cache_size_mutex);
2329
ad01c9e3 2330 for (i = conf->max_nr_stripes; i; i--) {
845b9e22 2331 nsh = alloc_stripe(sc, GFP_KERNEL, newsize, conf);
ad01c9e3
N		 2332 if (!nsh)
2333 break;
2334
ad01c9e3
N		 2335 list_add(&nsh->lru, &newstripes);
2336 }
2337 if (i) {
2338 /* didn't get enough, give up */
2339 while (!list_empty(&newstripes)) {
2340 nsh = list_entry(newstripes.next, struct stripe_head, lru);
2341 list_del(&nsh->lru);
845b9e22 2342 free_stripe(sc, nsh);
ad01c9e3
N		 2343 }
2344 kmem_cache_destroy(sc);
2d5b569b 2345 mutex_unlock(&conf->cache_size_mutex);
ad01c9e3
N		 2346 return -ENOMEM;
2347 }
2348 /* Step 2 - Must use GFP_NOIO now.
2349 * OK, we have enough stripes, start collecting inactive
2350 * stripes and copying them over
2351 */
566c09c5
SL		 2352 hash = 0;
2353 cnt = 0;
ad01c9e3 2354 list_for_each_entry(nsh, &newstripes, lru) {
566c09c5 2355 lock_device_hash_lock(conf, hash);
6ab2a4b8 2356 wait_event_cmd(conf->wait_for_stripe,
566c09c5
SL		 2357 !list_empty(conf->inactive_list + hash),
2358 unlock_device_hash_lock(conf, hash),
2359 lock_device_hash_lock(conf, hash));
2360 osh = get_free_stripe(conf, hash);
2361 unlock_device_hash_lock(conf, hash);
f18c1a35 2362
d592a996 2363 for(i=0; i<conf->pool_size; i++) {
ad01c9e3 2364 nsh->dev[i].page = osh->dev[i].page;
d592a996
SL		 2365 nsh->dev[i].orig_page = osh->dev[i].page;
2366 }
566c09c5 2367 nsh->hash_lock_index = hash;
845b9e22 2368 free_stripe(conf->slab_cache, osh);
566c09c5
SL		 2369 cnt++;
2370 if (cnt >= conf->max_nr_stripes / NR_STRIPE_HASH_LOCKS +
2371 !!((conf->max_nr_stripes % NR_STRIPE_HASH_LOCKS) > hash)) {
2372 hash++;
2373 cnt = 0;
2374 }
ad01c9e3
N		 2375 }
2376 kmem_cache_destroy(conf->slab_cache);
2377
2378 /* Step 3.
2379 * At this point, we are holding all the stripes so the array
2380 * is completely stalled, so now is a good time to resize
d6f38f31 2381 * conf->disks and the scribble region
ad01c9e3 2382 */
6396bb22 2383 ndisks = kcalloc(newsize, sizeof(struct disk_info), GFP_NOIO);
ad01c9e3 2384 if (ndisks) {
d7bd398e 2385 for (i = 0; i < conf->pool_size; i++)
ad01c9e3 2386 ndisks[i] = conf->disks[i];
d7bd398e
SL		 2387
2388 for (i = conf->pool_size; i < newsize; i++) {
2389 ndisks[i].extra_page = alloc_page(GFP_NOIO);
2390 if (!ndisks[i].extra_page)
2391 err = -ENOMEM;
2392 }
2393
2394 if (err) {
2395 for (i = conf->pool_size; i < newsize; i++)
2396 if (ndisks[i].extra_page)
2397 put_page(ndisks[i].extra_page);
2398 kfree(ndisks);
2399 } else {
2400 kfree(conf->disks);
2401 conf->disks = ndisks;
2402 }
ad01c9e3
N		 2403 } else
2404 err = -ENOMEM;
2405
2d5b569b 2406 mutex_unlock(&conf->cache_size_mutex);
583da48e
DY		 2407
2408 conf->slab_cache = sc;
2409 conf->active_name = 1-conf->active_name;
2410
ad01c9e3
N		 2411 /* Step 4, return new stripes to service */
2412 while(!list_empty(&newstripes)) {
2413 nsh = list_entry(newstripes.next, struct stripe_head, lru);
2414 list_del_init(&nsh->lru);
d6f38f31 2415
ad01c9e3
N		 2416 for (i=conf->raid_disks; i < newsize; i++)
2417 if (nsh->dev[i].page == NULL) {
2418 struct page *p = alloc_page(GFP_NOIO);
2419 nsh->dev[i].page = p;
d592a996 2420 nsh->dev[i].orig_page = p;
ad01c9e3
N		 2421 if (!p)
2422 err = -ENOMEM;
2423 }
6d036f7d 2424 raid5_release_stripe(nsh);
ad01c9e3
N		 2425 }
2426 /* critical section pass, GFP_NOIO no longer needed */
2427
6e9eac2d
N		 2428 if (!err)
2429 conf->pool_size = newsize;
ad01c9e3
N		 2430 return err;
2431}
1da177e4 2432
486f0644 2433static int drop_one_stripe(struct r5conf *conf)
1da177e4
LT		 2434{
2435 struct stripe_head *sh;
49895bcc 2436 int hash = (conf->max_nr_stripes - 1) & STRIPE_HASH_LOCKS_MASK;
1da177e4 2437
566c09c5
SL		 2438 spin_lock_irq(conf->hash_locks + hash);
2439 sh = get_free_stripe(conf, hash);
2440 spin_unlock_irq(conf->hash_locks + hash);
3f294f4f
N		 2441 if (!sh)
2442 return 0;
78bafebd 2443 BUG_ON(atomic_read(&sh->count));
e4e11e38 2444 shrink_buffers(sh);
845b9e22 2445 free_stripe(conf->slab_cache, sh);
3f294f4f 2446 atomic_dec(&conf->active_stripes);
486f0644 2447 conf->max_nr_stripes--;
3f294f4f
N		 2448 return 1;
2449}
2450
d1688a6d 2451static void shrink_stripes(struct r5conf *conf)
3f294f4f 2452{
486f0644
N		 2453 while (conf->max_nr_stripes &&
2454 drop_one_stripe(conf))
2455 ;
3f294f4f 2456
644df1a8 2457 kmem_cache_destroy(conf->slab_cache);
1da177e4
LT		 2458 conf->slab_cache = NULL;
2459}
2460
4246a0b6 2461static void raid5_end_read_request(struct bio * bi)
1da177e4 2462{
99c0fb5f 2463 struct stripe_head *sh = bi->bi_private;
d1688a6d 2464 struct r5conf *conf = sh->raid_conf;
7ecaa1e6 2465 int disks = sh->disks, i;
d6950432 2466 char b[BDEVNAME_SIZE];
dd054fce 2467 struct md_rdev *rdev = NULL;
05616be5 2468 sector_t s;
1da177e4
LT		 2469
2470 for (i=0 ; i<disks; i++)
2471 if (bi == &sh->dev[i].req)
2472 break;
2473
4246a0b6 2474 pr_debug("end_read_request %llu/%d, count: %d, error %d.\n",
45b4233c 2475 (unsigned long long)sh->sector, i, atomic_read(&sh->count),
4e4cbee9 2476 bi->bi_status);
1da177e4 2477 if (i == disks) {
5f9d1fde 2478 bio_reset(bi);
1da177e4 2479 BUG();
6712ecf8 2480 return;
1da177e4 2481 }
14a75d3e 2482 if (test_bit(R5_ReadRepl, &sh->dev[i].flags))
dd054fce
N		 2483 /* If replacement finished while this request was outstanding,
2484 * 'replacement' might be NULL already.
2485 * In that case it moved down to 'rdev'.
2486 * rdev is not removed until all requests are finished.
2487 */
14a75d3e 2488 rdev = conf->disks[i].replacement;
dd054fce 2489 if (!rdev)
14a75d3e 2490 rdev = conf->disks[i].rdev;
1da177e4 2491
05616be5
N		 2492 if (use_new_offset(conf, sh))
2493 s = sh->sector + rdev->new_data_offset;
2494 else
2495 s = sh->sector + rdev->data_offset;
4e4cbee9 2496 if (!bi->bi_status) {
1da177e4 2497 set_bit(R5_UPTODATE, &sh->dev[i].flags);
4e5314b5 2498 if (test_bit(R5_ReadError, &sh->dev[i].flags)) {
14a75d3e
N		 2499 /* Note that this cannot happen on a
2500 * replacement device. We just fail those on
2501 * any error
2502 */
cc6167b4
N		 2503 pr_info_ratelimited(
2504 "md/raid:%s: read error corrected (%lu sectors at %llu on %s)\n",
8bda470e 2505 mdname(conf->mddev), STRIPE_SECTORS,
05616be5 2506 (unsigned long long)s,
8bda470e 2507 bdevname(rdev->bdev, b));
ddd5115f 2508 atomic_add(STRIPE_SECTORS, &rdev->corrected_errors);
4e5314b5
N		 2509 clear_bit(R5_ReadError, &sh->dev[i].flags);
2510 clear_bit(R5_ReWrite, &sh->dev[i].flags);
3f9e7c14 2511 } else if (test_bit(R5_ReadNoMerge, &sh->dev[i].flags))
2512 clear_bit(R5_ReadNoMerge, &sh->dev[i].flags);
2513
86aa1397
SL		 2514 if (test_bit(R5_InJournal, &sh->dev[i].flags))
2515 /*
2516 * end read for a page in journal, this
2517 * must be preparing for prexor in rmw
2518 */
2519 set_bit(R5_OrigPageUPTDODATE, &sh->dev[i].flags);
2520
14a75d3e
N		 2521 if (atomic_read(&rdev->read_errors))
2522 atomic_set(&rdev->read_errors, 0);
1da177e4 2523 } else {
14a75d3e 2524 const char *bdn = bdevname(rdev->bdev, b);
ba22dcbf 2525 int retry = 0;
2e8ac303 2526 int set_bad = 0;
d6950432 2527
1da177e4 2528 clear_bit(R5_UPTODATE, &sh->dev[i].flags);
d6950432 2529 atomic_inc(&rdev->read_errors);
14a75d3e 2530 if (test_bit(R5_ReadRepl, &sh->dev[i].flags))
cc6167b4
N		 2531 pr_warn_ratelimited(
2532 "md/raid:%s: read error on replacement device (sector %llu on %s).\n",
14a75d3e 2533 mdname(conf->mddev),
05616be5 2534 (unsigned long long)s,
14a75d3e 2535 bdn);
2e8ac303 2536 else if (conf->mddev->degraded >= conf->max_degraded) {
2537 set_bad = 1;
cc6167b4
N		 2538 pr_warn_ratelimited(
2539 "md/raid:%s: read error not correctable (sector %llu on %s).\n",
8bda470e 2540 mdname(conf->mddev),
05616be5 2541 (unsigned long long)s,
8bda470e 2542 bdn);
2e8ac303 2543 } else if (test_bit(R5_ReWrite, &sh->dev[i].flags)) {
4e5314b5 2544 /* Oh, no!!! */
2e8ac303 2545 set_bad = 1;
cc6167b4
N		 2546 pr_warn_ratelimited(
2547 "md/raid:%s: read error NOT corrected!! (sector %llu on %s).\n",
8bda470e 2548 mdname(conf->mddev),
05616be5 2549 (unsigned long long)s,
8bda470e 2550 bdn);
2e8ac303 2551 } else if (atomic_read(&rdev->read_errors)
ba22dcbf 2552 > conf->max_nr_stripes)
cc6167b4 2553 pr_warn("md/raid:%s: Too many read errors, failing device %s.\n",
d6950432 2554 mdname(conf->mddev), bdn);
ba22dcbf
N		 2555 else
2556 retry = 1;
edfa1f65
BY		 2557 if (set_bad && test_bit(In_sync, &rdev->flags)
2558 && !test_bit(R5_ReadNoMerge, &sh->dev[i].flags))
2559 retry = 1;
ba22dcbf 2560 if (retry)
3f9e7c14 2561 if (test_bit(R5_ReadNoMerge, &sh->dev[i].flags)) {
2562 set_bit(R5_ReadError, &sh->dev[i].flags);
2563 clear_bit(R5_ReadNoMerge, &sh->dev[i].flags);
2564 } else
2565 set_bit(R5_ReadNoMerge, &sh->dev[i].flags);
ba22dcbf 2566 else {
4e5314b5
N		 2567 clear_bit(R5_ReadError, &sh->dev[i].flags);
2568 clear_bit(R5_ReWrite, &sh->dev[i].flags);
2e8ac303 2569 if (!(set_bad
2570 && test_bit(In_sync, &rdev->flags)
2571 && rdev_set_badblocks(
2572 rdev, sh->sector, STRIPE_SECTORS, 0)))
2573 md_error(conf->mddev, rdev);
ba22dcbf 2574 }
1da177e4 2575 }
14a75d3e 2576 rdev_dec_pending(rdev, conf->mddev);
c9445555 2577 bio_reset(bi);
1da177e4
LT		 2578 clear_bit(R5_LOCKED, &sh->dev[i].flags);
2579 set_bit(STRIPE_HANDLE, &sh->state);
6d036f7d 2580 raid5_release_stripe(sh);
1da177e4
LT		 2581}
2582
4246a0b6 2583static void raid5_end_write_request(struct bio *bi)
1da177e4 2584{
99c0fb5f 2585 struct stripe_head *sh = bi->bi_private;
d1688a6d 2586 struct r5conf *conf = sh->raid_conf;
7ecaa1e6 2587 int disks = sh->disks, i;
977df362 2588 struct md_rdev *uninitialized_var(rdev);
b84db560
N		 2589 sector_t first_bad;
2590 int bad_sectors;
977df362 2591 int replacement = 0;
1da177e4 2592
977df362
N		 2593 for (i = 0 ; i < disks; i++) {
2594 if (bi == &sh->dev[i].req) {
2595 rdev = conf->disks[i].rdev;
1da177e4 2596 break;
977df362
N		 2597 }
2598 if (bi == &sh->dev[i].rreq) {
2599 rdev = conf->disks[i].replacement;
dd054fce
N		 2600 if (rdev)
2601 replacement = 1;
2602 else
2603 /* rdev was removed and 'replacement'
2604 * replaced it. rdev is not removed
2605 * until all requests are finished.
2606 */
2607 rdev = conf->disks[i].rdev;
977df362
N		 2608 break;
2609 }
2610 }
4246a0b6 2611 pr_debug("end_write_request %llu/%d, count %d, error: %d.\n",
1da177e4 2612 (unsigned long long)sh->sector, i, atomic_read(&sh->count),
4e4cbee9 2613 bi->bi_status);
1da177e4 2614 if (i == disks) {
5f9d1fde 2615 bio_reset(bi);
1da177e4 2616 BUG();
6712ecf8 2617 return;
1da177e4
LT		 2618 }
2619
977df362 2620 if (replacement) {
4e4cbee9 2621 if (bi->bi_status)
977df362
N		 2622 md_error(conf->mddev, rdev);
2623 else if (is_badblock(rdev, sh->sector,
2624 STRIPE_SECTORS,
2625 &first_bad, &bad_sectors))
2626 set_bit(R5_MadeGoodRepl, &sh->dev[i].flags);
2627 } else {
4e4cbee9 2628 if (bi->bi_status) {
9f97e4b1 2629 set_bit(STRIPE_DEGRADED, &sh->state);
977df362
N		 2630 set_bit(WriteErrorSeen, &rdev->flags);
2631 set_bit(R5_WriteError, &sh->dev[i].flags);
3a6de292
N		 2632 if (!test_and_set_bit(WantReplacement, &rdev->flags))
2633 set_bit(MD_RECOVERY_NEEDED,
2634 &rdev->mddev->recovery);
977df362
N		 2635 } else if (is_badblock(rdev, sh->sector,
2636 STRIPE_SECTORS,
c0b32972 2637 &first_bad, &bad_sectors)) {
977df362 2638 set_bit(R5_MadeGood, &sh->dev[i].flags);
c0b32972
N		 2639 if (test_bit(R5_ReadError, &sh->dev[i].flags))
2640 /* That was a successful write so make
2641 * sure it looks like we already did
2642 * a re-write.
2643 */
2644 set_bit(R5_ReWrite, &sh->dev[i].flags);
2645 }
977df362
N		 2646 }
2647 rdev_dec_pending(rdev, conf->mddev);
1da177e4 2648
4e4cbee9 2649 if (sh->batch_head && bi->bi_status && !replacement)
72ac7330 2650 set_bit(STRIPE_BATCH_ERR, &sh->batch_head->state);
2651
c9445555 2652 bio_reset(bi);
977df362
N		 2653 if (!test_and_clear_bit(R5_DOUBLE_LOCKED, &sh->dev[i].flags))
2654 clear_bit(R5_LOCKED, &sh->dev[i].flags);
1da177e4 2655 set_bit(STRIPE_HANDLE, &sh->state);
6d036f7d 2656 raid5_release_stripe(sh);
59fc630b 2657
2658 if (sh->batch_head && sh != sh->batch_head)
6d036f7d 2659 raid5_release_stripe(sh->batch_head);
1da177e4
LT		 2660}
2661
849674e4 2662static void raid5_error(struct mddev *mddev, struct md_rdev *rdev)
1da177e4
LT		 2663{
2664 char b[BDEVNAME_SIZE];
d1688a6d 2665 struct r5conf *conf = mddev->private;
908f4fbd 2666 unsigned long flags;
0c55e022 2667 pr_debug("raid456: error called\n");
1da177e4 2668
908f4fbd 2669 spin_lock_irqsave(&conf->device_lock, flags);
fb73b357
MT		 2670
2671 if (test_bit(In_sync, &rdev->flags) &&
2672 mddev->degraded == conf->max_degraded) {
2673 /*
2674 * Don't allow to achieve failed state
2675 * Don't try to recover this device
2676 */
2677 conf->recovery_disabled = mddev->recovery_disabled;
2678 spin_unlock_irqrestore(&conf->device_lock, flags);
2679 return;
2680 }
2681
aff69d89 2682 set_bit(Faulty, &rdev->flags);
908f4fbd 2683 clear_bit(In_sync, &rdev->flags);
2e38a37f 2684 mddev->degraded = raid5_calc_degraded(conf);
908f4fbd
N		 2685 spin_unlock_irqrestore(&conf->device_lock, flags);
2686 set_bit(MD_RECOVERY_INTR, &mddev->recovery);
2687
de393cde 2688 set_bit(Blocked, &rdev->flags);
2953079c
SL		 2689 set_mask_bits(&mddev->sb_flags, 0,
2690 BIT(MD_SB_CHANGE_DEVS) | BIT(MD_SB_CHANGE_PENDING));
cc6167b4
N		 2691 pr_crit("md/raid:%s: Disk failure on %s, disabling device.\n"
2692 "md/raid:%s: Operation continuing on %d devices.\n",
2693 mdname(mddev),
2694 bdevname(rdev->bdev, b),
2695 mdname(mddev),
2696 conf->raid_disks - mddev->degraded);
70d466f7 2697 r5c_update_on_rdev_error(mddev, rdev);
16a53ecc 2698}
1da177e4
LT		 2699
2700/*
2701 * Input: a 'big' sector number,
2702 * Output: index of the data and parity disk, and the sector # in them.
2703 */
6d036f7d
SL		 2704sector_t raid5_compute_sector(struct r5conf *conf, sector_t r_sector,
2705 int previous, int *dd_idx,
2706 struct stripe_head *sh)
1da177e4 2707{
6e3b96ed 2708 sector_t stripe, stripe2;
35f2a591 2709 sector_t chunk_number;
1da177e4 2710 unsigned int chunk_offset;
911d4ee8 2711 int pd_idx, qd_idx;
67cc2b81 2712 int ddf_layout = 0;
1da177e4 2713 sector_t new_sector;
e183eaed
N		 2714 int algorithm = previous ? conf->prev_algo
2715 : conf->algorithm;
09c9e5fa
AN		 2716 int sectors_per_chunk = previous ? conf->prev_chunk_sectors
2717 : conf->chunk_sectors;
112bf897
N		 2718 int raid_disks = previous ? conf->previous_raid_disks
2719 : conf->raid_disks;
2720 int data_disks = raid_disks - conf->max_degraded;
1da177e4
LT		 2721
2722 /* First compute the information on this sector */
2723
2724 /*
2725 * Compute the chunk number and the sector offset inside the chunk
2726 */
2727 chunk_offset = sector_div(r_sector, sectors_per_chunk);
2728 chunk_number = r_sector;
1da177e4
LT		 2729
2730 /*
2731 * Compute the stripe number
2732 */
35f2a591
N		 2733 stripe = chunk_number;
2734 *dd_idx = sector_div(stripe, data_disks);
6e3b96ed 2735 stripe2 = stripe;
1da177e4
LT		 2736 /*
2737 * Select the parity disk based on the user selected algorithm.
2738 */
84789554 2739 pd_idx = qd_idx = -1;
16a53ecc
N		 2740 switch(conf->level) {
2741 case 4:
911d4ee8 2742 pd_idx = data_disks;
16a53ecc
N		 2743 break;
2744 case 5:
e183eaed 2745 switch (algorithm) {
1da177e4 2746 case ALGORITHM_LEFT_ASYMMETRIC:
6e3b96ed 2747 pd_idx = data_disks - sector_div(stripe2, raid_disks);
911d4ee8 2748 if (*dd_idx >= pd_idx)
1da177e4
LT		 2749 (*dd_idx)++;
2750 break;
2751 case ALGORITHM_RIGHT_ASYMMETRIC:
6e3b96ed 2752 pd_idx = sector_div(stripe2, raid_disks);
911d4ee8 2753 if (*dd_idx >= pd_idx)
1da177e4
LT		 2754 (*dd_idx)++;
2755 break;
2756 case ALGORITHM_LEFT_SYMMETRIC:
6e3b96ed 2757 pd_idx = data_disks - sector_div(stripe2, raid_disks);
911d4ee8 2758 *dd_idx = (pd_idx + 1 + *dd_idx) % raid_disks;
1da177e4
LT		 2759 break;
2760 case ALGORITHM_RIGHT_SYMMETRIC:
6e3b96ed 2761 pd_idx = sector_div(stripe2, raid_disks);
911d4ee8 2762 *dd_idx = (pd_idx + 1 + *dd_idx) % raid_disks;
1da177e4 2763 break;
99c0fb5f
N		 2764 case ALGORITHM_PARITY_0:
2765 pd_idx = 0;
2766 (*dd_idx)++;
2767 break;
2768 case ALGORITHM_PARITY_N:
2769 pd_idx = data_disks;
2770 break;
1da177e4 2771 default:
99c0fb5f 2772 BUG();
16a53ecc
N		 2773 }
2774 break;
2775 case 6:
2776
e183eaed 2777 switch (algorithm) {
16a53ecc 2778 case ALGORITHM_LEFT_ASYMMETRIC:
6e3b96ed 2779 pd_idx = raid_disks - 1 - sector_div(stripe2, raid_disks);
911d4ee8
N		 2780 qd_idx = pd_idx + 1;
2781 if (pd_idx == raid_disks-1) {
99c0fb5f 2782 (*dd_idx)++; /* Q D D D P */
911d4ee8
N		 2783 qd_idx = 0;
2784 } else if (*dd_idx >= pd_idx)
16a53ecc
N		 2785 (*dd_idx) += 2; /* D D P Q D */
2786 break;
2787 case ALGORITHM_RIGHT_ASYMMETRIC:
6e3b96ed 2788 pd_idx = sector_div(stripe2, raid_disks);
911d4ee8
N		 2789 qd_idx = pd_idx + 1;
2790 if (pd_idx == raid_disks-1) {
99c0fb5f 2791 (*dd_idx)++; /* Q D D D P */
911d4ee8
N		 2792 qd_idx = 0;
2793 } else if (*dd_idx >= pd_idx)
16a53ecc
N		 2794 (*dd_idx) += 2; /* D D P Q D */
2795 break;
2796 case ALGORITHM_LEFT_SYMMETRIC:
6e3b96ed 2797 pd_idx = raid_disks - 1 - sector_div(stripe2, raid_disks);
911d4ee8
N		 2798 qd_idx = (pd_idx + 1) % raid_disks;
2799 *dd_idx = (pd_idx + 2 + *dd_idx) % raid_disks;
16a53ecc
N		 2800 break;
2801 case ALGORITHM_RIGHT_SYMMETRIC:
6e3b96ed 2802 pd_idx = sector_div(stripe2, raid_disks);
911d4ee8
N		 2803 qd_idx = (pd_idx + 1) % raid_disks;
2804 *dd_idx = (pd_idx + 2 + *dd_idx) % raid_disks;
16a53ecc 2805 break;
99c0fb5f
N		 2806
2807 case ALGORITHM_PARITY_0:
2808 pd_idx = 0;
2809 qd_idx = 1;
2810 (*dd_idx) += 2;
2811 break;
2812 case ALGORITHM_PARITY_N:
2813 pd_idx = data_disks;
2814 qd_idx = data_disks + 1;
2815 break;
2816
2817 case ALGORITHM_ROTATING_ZERO_RESTART:
2818 /* Exactly the same as RIGHT_ASYMMETRIC, but or
2819 * of blocks for computing Q is different.
2820 */
6e3b96ed 2821 pd_idx = sector_div(stripe2, raid_disks);
99c0fb5f
N		 2822 qd_idx = pd_idx + 1;
2823 if (pd_idx == raid_disks-1) {
2824 (*dd_idx)++; /* Q D D D P */
2825 qd_idx = 0;
2826 } else if (*dd_idx >= pd_idx)
2827 (*dd_idx) += 2; /* D D P Q D */
67cc2b81 2828 ddf_layout = 1;
99c0fb5f
N		 2829 break;
2830
2831 case ALGORITHM_ROTATING_N_RESTART:
2832 /* Same a left_asymmetric, by first stripe is
2833 * D D D P Q rather than
2834 * Q D D D P
2835 */
6e3b96ed
N		 2836 stripe2 += 1;
2837 pd_idx = raid_disks - 1 - sector_div(stripe2, raid_disks);
99c0fb5f
N		 2838 qd_idx = pd_idx + 1;
2839 if (pd_idx == raid_disks-1) {
2840 (*dd_idx)++; /* Q D D D P */
2841 qd_idx = 0;
2842 } else if (*dd_idx >= pd_idx)
2843 (*dd_idx) += 2; /* D D P Q D */
67cc2b81 2844 ddf_layout = 1;
99c0fb5f
N		 2845 break;
2846
2847 case ALGORITHM_ROTATING_N_CONTINUE:
2848 /* Same as left_symmetric but Q is before P */
6e3b96ed 2849 pd_idx = raid_disks - 1 - sector_div(stripe2, raid_disks);
99c0fb5f
N		 2850 qd_idx = (pd_idx + raid_disks - 1) % raid_disks;
2851 *dd_idx = (pd_idx + 1 + *dd_idx) % raid_disks;
67cc2b81 2852 ddf_layout = 1;
99c0fb5f
N		 2853 break;
2854
2855 case ALGORITHM_LEFT_ASYMMETRIC_6:
2856 /* RAID5 left_asymmetric, with Q on last device */
6e3b96ed 2857 pd_idx = data_disks - sector_div(stripe2, raid_disks-1);
99c0fb5f
N		 2858 if (*dd_idx >= pd_idx)
2859 (*dd_idx)++;
2860 qd_idx = raid_disks - 1;
2861 break;
2862
2863 case ALGORITHM_RIGHT_ASYMMETRIC_6:
6e3b96ed 2864 pd_idx = sector_div(stripe2, raid_disks-1);
99c0fb5f
N		 2865 if (*dd_idx >= pd_idx)
2866 (*dd_idx)++;
2867 qd_idx = raid_disks - 1;
2868 break;
2869
2870 case ALGORITHM_LEFT_SYMMETRIC_6:
6e3b96ed 2871 pd_idx = data_disks - sector_div(stripe2, raid_disks-1);
99c0fb5f
N		 2872 *dd_idx = (pd_idx + 1 + *dd_idx) % (raid_disks-1);
2873 qd_idx = raid_disks - 1;
2874 break;
2875
2876 case ALGORITHM_RIGHT_SYMMETRIC_6:
6e3b96ed 2877 pd_idx = sector_div(stripe2, raid_disks-1);
99c0fb5f
N		 2878 *dd_idx = (pd_idx + 1 + *dd_idx) % (raid_disks-1);
2879 qd_idx = raid_disks - 1;
2880 break;
2881
2882 case ALGORITHM_PARITY_0_6:
2883 pd_idx = 0;
2884 (*dd_idx)++;
2885 qd_idx = raid_disks - 1;
2886 break;
2887
16a53ecc 2888 default:
99c0fb5f 2889 BUG();
16a53ecc
N		 2890 }
2891 break;
1da177e4
LT		 2892 }
2893
911d4ee8
N		 2894 if (sh) {
2895 sh->pd_idx = pd_idx;
2896 sh->qd_idx = qd_idx;
67cc2b81 2897 sh->ddf_layout = ddf_layout;
911d4ee8 2898 }
1da177e4
LT		 2899 /*
2900 * Finally, compute the new sector number
2901 */
2902 new_sector = (sector_t)stripe * sectors_per_chunk + chunk_offset;
2903 return new_sector;
2904}
2905
6d036f7d 2906sector_t raid5_compute_blocknr(struct stripe_head *sh, int i, int previous)
1da177e4 2907{
d1688a6d 2908 struct r5conf *conf = sh->raid_conf;
b875e531
N		 2909 int raid_disks = sh->disks;
2910 int data_disks = raid_disks - conf->max_degraded;
1da177e4 2911 sector_t new_sector = sh->sector, check;
09c9e5fa
AN		 2912 int sectors_per_chunk = previous ? conf->prev_chunk_sectors
2913 : conf->chunk_sectors;
e183eaed
N		 2914 int algorithm = previous ? conf->prev_algo
2915 : conf->algorithm;
1da177e4
LT		 2916 sector_t stripe;
2917 int chunk_offset;
35f2a591
N		 2918 sector_t chunk_number;
2919 int dummy1, dd_idx = i;
1da177e4 2920 sector_t r_sector;
911d4ee8 2921 struct stripe_head sh2;
1da177e4
LT		 2922
2923 chunk_offset = sector_div(new_sector, sectors_per_chunk);
2924 stripe = new_sector;
1da177e4 2925
16a53ecc
N		 2926 if (i == sh->pd_idx)
2927 return 0;
2928 switch(conf->level) {
2929 case 4: break;
2930 case 5:
e183eaed 2931 switch (algorithm) {
1da177e4
LT		 2932 case ALGORITHM_LEFT_ASYMMETRIC:
2933 case ALGORITHM_RIGHT_ASYMMETRIC:
2934 if (i > sh->pd_idx)
2935 i--;
2936 break;
2937 case ALGORITHM_LEFT_SYMMETRIC:
2938 case ALGORITHM_RIGHT_SYMMETRIC:
2939 if (i < sh->pd_idx)
2940 i += raid_disks;
2941 i -= (sh->pd_idx + 1);
2942 break;
99c0fb5f
N		 2943 case ALGORITHM_PARITY_0:
2944 i -= 1;
2945 break;
2946 case ALGORITHM_PARITY_N:
2947 break;
1da177e4 2948 default:
99c0fb5f 2949 BUG();
16a53ecc
N		 2950 }
2951 break;
2952 case 6:
d0dabf7e 2953 if (i == sh->qd_idx)
16a53ecc 2954 return 0; /* It is the Q disk */
e183eaed 2955 switch (algorithm) {
16a53ecc
N		 2956 case ALGORITHM_LEFT_ASYMMETRIC:
2957 case ALGORITHM_RIGHT_ASYMMETRIC:
99c0fb5f
N		 2958 case ALGORITHM_ROTATING_ZERO_RESTART:
2959 case ALGORITHM_ROTATING_N_RESTART:
2960 if (sh->pd_idx == raid_disks-1)
2961 i--; /* Q D D D P */
16a53ecc
N		 2962 else if (i > sh->pd_idx)
2963 i -= 2; /* D D P Q D */
2964 break;
2965 case ALGORITHM_LEFT_SYMMETRIC:
2966 case ALGORITHM_RIGHT_SYMMETRIC:
2967 if (sh->pd_idx == raid_disks-1)
2968 i--; /* Q D D D P */
2969 else {
2970 /* D D P Q D */
2971 if (i < sh->pd_idx)
2972 i += raid_disks;
2973 i -= (sh->pd_idx + 2);
2974 }
2975 break;
99c0fb5f
N		 2976 case ALGORITHM_PARITY_0:
2977 i -= 2;
2978 break;
2979 case ALGORITHM_PARITY_N:
2980 break;
2981 case ALGORITHM_ROTATING_N_CONTINUE:
e4424fee 2982 /* Like left_symmetric, but P is before Q */
99c0fb5f
N		 2983 if (sh->pd_idx == 0)
2984 i--; /* P D D D Q */
e4424fee
N		 2985 else {
2986 /* D D Q P D */
2987 if (i < sh->pd_idx)
2988 i += raid_disks;
2989 i -= (sh->pd_idx + 1);
2990 }
99c0fb5f
N		 2991 break;
2992 case ALGORITHM_LEFT_ASYMMETRIC_6:
2993 case ALGORITHM_RIGHT_ASYMMETRIC_6:
2994 if (i > sh->pd_idx)
2995 i--;
2996 break;
2997 case ALGORITHM_LEFT_SYMMETRIC_6:
2998 case ALGORITHM_RIGHT_SYMMETRIC_6:
2999 if (i < sh->pd_idx)
3000 i += data_disks + 1;
3001 i -= (sh->pd_idx + 1);
3002 break;
3003 case ALGORITHM_PARITY_0_6:
3004 i -= 1;
3005 break;
16a53ecc 3006 default:
99c0fb5f 3007 BUG();
16a53ecc
N		 3008 }
3009 break;
1da177e4
LT		 3010 }
3011
3012 chunk_number = stripe * data_disks + i;
35f2a591 3013 r_sector = chunk_number * sectors_per_chunk + chunk_offset;
1da177e4 3014
112bf897 3015 check = raid5_compute_sector(conf, r_sector,
784052ec 3016 previous, &dummy1, &sh2);
911d4ee8
N		 3017 if (check != sh->sector || dummy1 != dd_idx || sh2.pd_idx != sh->pd_idx
3018 || sh2.qd_idx != sh->qd_idx) {
cc6167b4
N		 3019 pr_warn("md/raid:%s: compute_blocknr: map not correct\n",
3020 mdname(conf->mddev));
1da177e4
LT		 3021 return 0;
3022 }
3023 return r_sector;
3024}
3025
07e83364
SL		 3026/*
3027 * There are cases where we want handle_stripe_dirtying() and
3028 * schedule_reconstruction() to delay towrite to some dev of a stripe.
3029 *
3030 * This function checks whether we want to delay the towrite. Specifically,
3031 * we delay the towrite when:
3032 *
3033 * 1. degraded stripe has a non-overwrite to the missing dev, AND this
3034 * stripe has data in journal (for other devices).
3035 *
3036 * In this case, when reading data for the non-overwrite dev, it is
3037 * necessary to handle complex rmw of write back cache (prexor with
3038 * orig_page, and xor with page). To keep read path simple, we would
3039 * like to flush data in journal to RAID disks first, so complex rmw
3040 * is handled in the write patch (handle_stripe_dirtying).
3041 *
39b99586
SL		 3042 * 2. when journal space is critical (R5C_LOG_CRITICAL=1)
3043 *
3044 * It is important to be able to flush all stripes in raid5-cache.
3045 * Therefore, we need reserve some space on the journal device for
3046 * these flushes. If flush operation includes pending writes to the
3047 * stripe, we need to reserve (conf->raid_disk + 1) pages per stripe
3048 * for the flush out. If we exclude these pending writes from flush
3049 * operation, we only need (conf->max_degraded + 1) pages per stripe.
3050 * Therefore, excluding pending writes in these cases enables more
3051 * efficient use of the journal device.
3052 *
3053 * Note: To make sure the stripe makes progress, we only delay
3054 * towrite for stripes with data already in journal (injournal > 0).
3055 * When LOG_CRITICAL, stripes with injournal == 0 will be sent to
3056 * no_space_stripes list.
3057 *
70d466f7
SL		 3058 * 3. during journal failure
3059 * In journal failure, we try to flush all cached data to raid disks
3060 * based on data in stripe cache. The array is read-only to upper
3061 * layers, so we would skip all pending writes.
3062 *
07e83364 3063 */
39b99586
SL		 3064static inline bool delay_towrite(struct r5conf *conf,
3065 struct r5dev *dev,
3066 struct stripe_head_state *s)
07e83364 3067{
39b99586
SL		 3068 /* case 1 above */
3069 if (!test_bit(R5_OVERWRITE, &dev->flags) &&
3070 !test_bit(R5_Insync, &dev->flags) && s->injournal)
3071 return true;
3072 /* case 2 above */
3073 if (test_bit(R5C_LOG_CRITICAL, &conf->cache_state) &&
3074 s->injournal > 0)
3075 return true;
70d466f7
SL		 3076 /* case 3 above */
3077 if (s->log_failed && s->injournal)
3078 return true;
39b99586 3079 return false;
07e83364
SL		 3080}
3081
600aa109 3082static void
c0f7bddb 3083schedule_reconstruction(struct stripe_head *sh, struct stripe_head_state *s,
600aa109 3084 int rcw, int expand)
e33129d8 3085{
584acdd4 3086 int i, pd_idx = sh->pd_idx, qd_idx = sh->qd_idx, disks = sh->disks;
d1688a6d 3087 struct r5conf *conf = sh->raid_conf;
c0f7bddb 3088 int level = conf->level;
e33129d8
DW		 3089
3090 if (rcw) {
1e6d690b
SL		 3091 /*
3092 * In some cases, handle_stripe_dirtying initially decided to
3093 * run rmw and allocates extra page for prexor. However, rcw is
3094 * cheaper later on. We need to free the extra page now,
3095 * because we won't be able to do that in ops_complete_prexor().
3096 */
3097 r5c_release_extra_page(sh);
e33129d8
DW		 3098
3099 for (i = disks; i--; ) {
3100 struct r5dev *dev = &sh->dev[i];
3101
39b99586 3102 if (dev->towrite && !delay_towrite(conf, dev, s)) {
e33129d8 3103 set_bit(R5_LOCKED, &dev->flags);
d8ee0728 3104 set_bit(R5_Wantdrain, &dev->flags);
e33129d8
DW		 3105 if (!expand)
3106 clear_bit(R5_UPTODATE, &dev->flags);
600aa109 3107 s->locked++;
1e6d690b
SL		 3108 } else if (test_bit(R5_InJournal, &dev->flags)) {
3109 set_bit(R5_LOCKED, &dev->flags);
3110 s->locked++;
e33129d8
DW		 3111 }
3112 }
ce7d363a
N		 3113 /* if we are not expanding this is a proper write request, and
3114 * there will be bios with new data to be drained into the
3115 * stripe cache
3116 */
3117 if (!expand) {
3118 if (!s->locked)
3119 /* False alarm, nothing to do */
3120 return;
3121 sh->reconstruct_state = reconstruct_state_drain_run;
3122 set_bit(STRIPE_OP_BIODRAIN, &s->ops_request);
3123 } else
3124 sh->reconstruct_state = reconstruct_state_run;
3125
3126 set_bit(STRIPE_OP_RECONSTRUCT, &s->ops_request);
3127
c0f7bddb 3128 if (s->locked + conf->max_degraded == disks)
8b3e6cdc 3129 if (!test_and_set_bit(STRIPE_FULL_WRITE, &sh->state))
c0f7bddb 3130 atomic_inc(&conf->pending_full_writes);
e33129d8
DW		 3131 } else {
3132 BUG_ON(!(test_bit(R5_UPTODATE, &sh->dev[pd_idx].flags) ||
3133 test_bit(R5_Wantcompute, &sh->dev[pd_idx].flags)));
584acdd4
MS		 3134 BUG_ON(level == 6 &&
3135 (!(test_bit(R5_UPTODATE, &sh->dev[qd_idx].flags) ||
3136 test_bit(R5_Wantcompute, &sh->dev[qd_idx].flags))));
e33129d8 3137
e33129d8
DW		 3138 for (i = disks; i--; ) {
3139 struct r5dev *dev = &sh->dev[i];
584acdd4 3140 if (i == pd_idx || i == qd_idx)
e33129d8
DW		 3141 continue;
3142
e33129d8
DW		 3143 if (dev->towrite &&
3144 (test_bit(R5_UPTODATE, &dev->flags) ||
d8ee0728
DW		 3145 test_bit(R5_Wantcompute, &dev->flags))) {
3146 set_bit(R5_Wantdrain, &dev->flags);
e33129d8
DW		 3147 set_bit(R5_LOCKED, &dev->flags);
3148 clear_bit(R5_UPTODATE, &dev->flags);
600aa109 3149 s->locked++;
1e6d690b
SL		 3150 } else if (test_bit(R5_InJournal, &dev->flags)) {
3151 set_bit(R5_LOCKED, &dev->flags);
3152 s->locked++;
e33129d8
DW		 3153 }
3154 }
ce7d363a
N		 3155 if (!s->locked)
3156 /* False alarm - nothing to do */
3157 return;
3158 sh->reconstruct_state = reconstruct_state_prexor_drain_run;
3159 set_bit(STRIPE_OP_PREXOR, &s->ops_request);
3160 set_bit(STRIPE_OP_BIODRAIN, &s->ops_request);
3161 set_bit(STRIPE_OP_RECONSTRUCT, &s->ops_request);
e33129d8
DW		 3162 }
3163
c0f7bddb 3164 /* keep the parity disk(s) locked while asynchronous operations
e33129d8
DW		 3165 * are in flight
3166 */
3167 set_bit(R5_LOCKED, &sh->dev[pd_idx].flags);
3168 clear_bit(R5_UPTODATE, &sh->dev[pd_idx].flags);
600aa109 3169 s->locked++;
e33129d8 3170
c0f7bddb
YT		 3171 if (level == 6) {
3172 int qd_idx = sh->qd_idx;
3173 struct r5dev *dev = &sh->dev[qd_idx];
3174
3175 set_bit(R5_LOCKED, &dev->flags);
3176 clear_bit(R5_UPTODATE, &dev->flags);
3177 s->locked++;
3178 }
3179
845b9e22 3180 if (raid5_has_ppl(sh->raid_conf) && sh->ppl_page &&
3418d036
AP		 3181 test_bit(STRIPE_OP_BIODRAIN, &s->ops_request) &&
3182 !test_bit(STRIPE_FULL_WRITE, &sh->state) &&
3183 test_bit(R5_Insync, &sh->dev[pd_idx].flags))
3184 set_bit(STRIPE_OP_PARTIAL_PARITY, &s->ops_request);
3185
600aa109 3186 pr_debug("%s: stripe %llu locked: %d ops_request: %lx\n",
e46b272b 3187 __func__, (unsigned long long)sh->sector,
600aa109 3188 s->locked, s->ops_request);
e33129d8 3189}
16a53ecc 3190
1da177e4
LT		 3191/*
3192 * Each stripe/dev can have one or more bion attached.
16a53ecc 3193 * toread/towrite point to the first in a chain.
1da177e4
LT		 3194 * The bi_next chain must be in order.
3195 */
da41ba65 3196static int add_stripe_bio(struct stripe_head *sh, struct bio *bi, int dd_idx,
3197 int forwrite, int previous)
1da177e4
LT		 3198{
3199 struct bio **bip;
d1688a6d 3200 struct r5conf *conf = sh->raid_conf;
72626685 3201 int firstwrite=0;
1da177e4 3202
cbe47ec5 3203 pr_debug("adding bi b#%llu to stripe s#%llu\n",
4f024f37 3204 (unsigned long long)bi->bi_iter.bi_sector,
1da177e4
LT		 3205 (unsigned long long)sh->sector);
3206
b17459c0 3207 spin_lock_irq(&sh->stripe_lock);
2cd259a7 3208 sh->dev[dd_idx].write_hint = bi->bi_write_hint;
59fc630b 3209 /* Don't allow new IO added to stripes in batch list */
3210 if (sh->batch_head)
3211 goto overlap;
72626685 3212 if (forwrite) {
1da177e4 3213 bip = &sh->dev[dd_idx].towrite;
7eaf7e8e 3214 if (*bip == NULL)
72626685
N		 3215 firstwrite = 1;
3216 } else
1da177e4 3217 bip = &sh->dev[dd_idx].toread;
4f024f37
KO		 3218 while (*bip && (*bip)->bi_iter.bi_sector < bi->bi_iter.bi_sector) {
3219 if (bio_end_sector(*bip) > bi->bi_iter.bi_sector)
1da177e4
LT		 3220 goto overlap;
3221 bip = & (*bip)->bi_next;
3222 }
4f024f37 3223 if (*bip && (*bip)->bi_iter.bi_sector < bio_end_sector(bi))
1da177e4
LT		 3224 goto overlap;
3225
3418d036
AP		 3226 if (forwrite && raid5_has_ppl(conf)) {
3227 /*
3228 * With PPL only writes to consecutive data chunks within a
3229 * stripe are allowed because for a single stripe_head we can
3230 * only have one PPL entry at a time, which describes one data
3231 * range. Not really an overlap, but wait_for_overlap can be
3232 * used to handle this.
3233 */
3234 sector_t sector;
3235 sector_t first = 0;
3236 sector_t last = 0;
3237 int count = 0;
3238 int i;
3239
3240 for (i = 0; i < sh->disks; i++) {
3241 if (i != sh->pd_idx &&
3242 (i == dd_idx || sh->dev[i].towrite)) {
3243 sector = sh->dev[i].sector;
3244 if (count == 0 || sector < first)
3245 first = sector;
3246 if (sector > last)
3247 last = sector;
3248 count++;
3249 }
3250 }
3251
3252 if (first + conf->chunk_sectors * (count - 1) != last)
3253 goto overlap;
3254 }
3255
da41ba65 3256 if (!forwrite || previous)
3257 clear_bit(STRIPE_BATCH_READY, &sh->state);
3258
78bafebd 3259 BUG_ON(*bip && bi->bi_next && (*bip) != bi->bi_next);
1da177e4
LT		 3260 if (*bip)
3261 bi->bi_next = *bip;
3262 *bip = bi;
016c76ac 3263 bio_inc_remaining(bi);
49728050 3264 md_write_inc(conf->mddev, bi);
72626685 3265
1da177e4
LT		 3266 if (forwrite) {
3267 /* check if page is covered */
3268 sector_t sector = sh->dev[dd_idx].sector;
3269 for (bi=sh->dev[dd_idx].towrite;
3270 sector < sh->dev[dd_idx].sector + STRIPE_SECTORS &&
4f024f37 3271 bi && bi->bi_iter.bi_sector <= sector;
1da177e4 3272 bi = r5_next_bio(bi, sh->dev[dd_idx].sector)) {
f73a1c7d
KO		 3273 if (bio_end_sector(bi) >= sector)
3274 sector = bio_end_sector(bi);
1da177e4
LT		 3275 }
3276 if (sector >= sh->dev[dd_idx].sector + STRIPE_SECTORS)
7a87f434 3277 if (!test_and_set_bit(R5_OVERWRITE, &sh->dev[dd_idx].flags))
3278 sh->overwrite_disks++;
1da177e4 3279 }
cbe47ec5
N		 3280
3281 pr_debug("added bi b#%llu to stripe s#%llu, disk %d.\n",
4f024f37 3282 (unsigned long long)(*bip)->bi_iter.bi_sector,
cbe47ec5
N		 3283 (unsigned long long)sh->sector, dd_idx);
3284
3285 if (conf->mddev->bitmap && firstwrite) {
d0852df5
N		 3286 /* Cannot hold spinlock over bitmap_startwrite,
3287 * but must ensure this isn't added to a batch until
3288 * we have added to the bitmap and set bm_seq.
3289 * So set STRIPE_BITMAP_PENDING to prevent
3290 * batching.
3291 * If multiple add_stripe_bio() calls race here they
3292 * much all set STRIPE_BITMAP_PENDING. So only the first one
3293 * to complete "bitmap_startwrite" gets to set
3294 * STRIPE_BIT_DELAY. This is important as once a stripe
3295 * is added to a batch, STRIPE_BIT_DELAY cannot be changed
3296 * any more.
3297 */
3298 set_bit(STRIPE_BITMAP_PENDING, &sh->state);
3299 spin_unlock_irq(&sh->stripe_lock);
e64e4018
AS		 3300 md_bitmap_startwrite(conf->mddev->bitmap, sh->sector,
3301 STRIPE_SECTORS, 0);
d0852df5
N		 3302 spin_lock_irq(&sh->stripe_lock);
3303 clear_bit(STRIPE_BITMAP_PENDING, &sh->state);
3304 if (!sh->batch_head) {
3305 sh->bm_seq = conf->seq_flush+1;
3306 set_bit(STRIPE_BIT_DELAY, &sh->state);
3307 }
cbe47ec5 3308 }
d0852df5 3309 spin_unlock_irq(&sh->stripe_lock);
59fc630b 3310
3311 if (stripe_can_batch(sh))
3312 stripe_add_to_batch_list(conf, sh);
1da177e4
LT		 3313 return 1;
3314
3315 overlap:
3316 set_bit(R5_Overlap, &sh->dev[dd_idx].flags);
b17459c0 3317 spin_unlock_irq(&sh->stripe_lock);
1da177e4
LT		 3318 return 0;
3319}
3320
d1688a6d 3321static void end_reshape(struct r5conf *conf);
29269553 3322
d1688a6d 3323static void stripe_set_idx(sector_t stripe, struct r5conf *conf, int previous,
911d4ee8 3324 struct stripe_head *sh)
ccfcc3c1 3325{
784052ec 3326 int sectors_per_chunk =
09c9e5fa 3327 previous ? conf->prev_chunk_sectors : conf->chunk_sectors;
911d4ee8 3328 int dd_idx;
2d2063ce 3329 int chunk_offset = sector_div(stripe, sectors_per_chunk);
112bf897 3330 int disks = previous ? conf->previous_raid_disks : conf->raid_disks;
2d2063ce 3331
112bf897
N		 3332 raid5_compute_sector(conf,
3333 stripe * (disks - conf->max_degraded)
b875e531 3334 *sectors_per_chunk + chunk_offset,
112bf897 3335 previous,
911d4ee8 3336 &dd_idx, sh);
ccfcc3c1
N		 3337}
3338
a4456856 3339static void
d1688a6d 3340handle_failed_stripe(struct r5conf *conf, struct stripe_head *sh,
bd83d0a2 3341 struct stripe_head_state *s, int disks)
a4456856
DW		 3342{
3343 int i;
59fc630b 3344 BUG_ON(sh->batch_head);
a4456856
DW		 3345 for (i = disks; i--; ) {
3346 struct bio *bi;
3347 int bitmap_end = 0;
3348
3349 if (test_bit(R5_ReadError, &sh->dev[i].flags)) {
3cb03002 3350 struct md_rdev *rdev;
a4456856
DW		 3351 rcu_read_lock();
3352 rdev = rcu_dereference(conf->disks[i].rdev);
f5b67ae8
N		 3353 if (rdev && test_bit(In_sync, &rdev->flags) &&
3354 !test_bit(Faulty, &rdev->flags))
7f0da59b
N		 3355 atomic_inc(&rdev->nr_pending);
3356 else
3357 rdev = NULL;
a4456856 3358 rcu_read_unlock();
7f0da59b
N		 3359 if (rdev) {
3360 if (!rdev_set_badblocks(
3361 rdev,
3362 sh->sector,
3363 STRIPE_SECTORS, 0))
3364 md_error(conf->mddev, rdev);
3365 rdev_dec_pending(rdev, conf->mddev);
3366 }
a4456856 3367 }
b17459c0 3368 spin_lock_irq(&sh->stripe_lock);
a4456856
DW		 3369 /* fail all writes first */
3370 bi = sh->dev[i].towrite;
3371 sh->dev[i].towrite = NULL;
7a87f434 3372 sh->overwrite_disks = 0;
b17459c0 3373 spin_unlock_irq(&sh->stripe_lock);
1ed850f3 3374 if (bi)
a4456856 3375 bitmap_end = 1;
a4456856 3376
ff875738 3377 log_stripe_write_finished(sh);
0576b1c6 3378
a4456856
DW		 3379 if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags))
3380 wake_up(&conf->wait_for_overlap);
3381
4f024f37 3382 while (bi && bi->bi_iter.bi_sector <
a4456856
DW		 3383 sh->dev[i].sector + STRIPE_SECTORS) {
3384 struct bio *nextbi = r5_next_bio(bi, sh->dev[i].sector);
4246a0b6 3385
49728050 3386 md_write_end(conf->mddev);
6308d8e3 3387 bio_io_error(bi);
a4456856
DW		 3388 bi = nextbi;
3389 }
7eaf7e8e 3390 if (bitmap_end)
e64e4018
AS		 3391 md_bitmap_endwrite(conf->mddev->bitmap, sh->sector,
3392 STRIPE_SECTORS, 0, 0);
7eaf7e8e 3393 bitmap_end = 0;
a4456856
DW		 3394 /* and fail all 'written' */
3395 bi = sh->dev[i].written;
3396 sh->dev[i].written = NULL;
d592a996
SL		 3397 if (test_and_clear_bit(R5_SkipCopy, &sh->dev[i].flags)) {
3398 WARN_ON(test_bit(R5_UPTODATE, &sh->dev[i].flags));
3399 sh->dev[i].page = sh->dev[i].orig_page;
3400 }
3401
a4456856 3402 if (bi) bitmap_end = 1;
4f024f37 3403 while (bi && bi->bi_iter.bi_sector <
a4456856
DW		 3404 sh->dev[i].sector + STRIPE_SECTORS) {
3405 struct bio *bi2 = r5_next_bio(bi, sh->dev[i].sector);
4246a0b6 3406
49728050 3407 md_write_end(conf->mddev);
6308d8e3 3408 bio_io_error(bi);
a4456856
DW		 3409 bi = bi2;
3410 }
3411
b5e98d65
DW		 3412 /* fail any reads if this device is non-operational and
3413 * the data has not reached the cache yet.
3414 */
3415 if (!test_bit(R5_Wantfill, &sh->dev[i].flags) &&
6e74a9cf 3416 s->failed > conf->max_degraded &&
b5e98d65
DW		 3417 (!test_bit(R5_Insync, &sh->dev[i].flags) ||
3418 test_bit(R5_ReadError, &sh->dev[i].flags))) {
143c4d05 3419 spin_lock_irq(&sh->stripe_lock);
a4456856
DW		 3420 bi = sh->dev[i].toread;
3421 sh->dev[i].toread = NULL;
143c4d05 3422 spin_unlock_irq(&sh->stripe_lock);
a4456856
DW		 3423 if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags))
3424 wake_up(&conf->wait_for_overlap);
ebda780b
SL		 3425 if (bi)
3426 s->to_read--;
4f024f37 3427 while (bi && bi->bi_iter.bi_sector <
a4456856
DW		 3428 sh->dev[i].sector + STRIPE_SECTORS) {
3429 struct bio *nextbi =
3430 r5_next_bio(bi, sh->dev[i].sector);
4246a0b6 3431
6308d8e3 3432 bio_io_error(bi);
a4456856
DW		 3433 bi = nextbi;
3434 }
3435 }
a4456856 3436 if (bitmap_end)
e64e4018
AS		 3437 md_bitmap_endwrite(conf->mddev->bitmap, sh->sector,
3438 STRIPE_SECTORS, 0, 0);
8cfa7b0f
N		 3439 /* If we were in the middle of a write the parity block might
3440 * still be locked - so just clear all R5_LOCKED flags
3441 */
3442 clear_bit(R5_LOCKED, &sh->dev[i].flags);
a4456856 3443 }
ebda780b
SL		 3444 s->to_write = 0;
3445 s->written = 0;
a4456856 3446
8b3e6cdc
DW		 3447 if (test_and_clear_bit(STRIPE_FULL_WRITE, &sh->state))
3448 if (atomic_dec_and_test(&conf->pending_full_writes))
3449 md_wakeup_thread(conf->mddev->thread);
a4456856
DW		 3450}
3451
7f0da59b 3452static void
d1688a6d 3453handle_failed_sync(struct r5conf *conf, struct stripe_head *sh,
7f0da59b
N		 3454 struct stripe_head_state *s)
3455{
3456 int abort = 0;
3457 int i;
3458
59fc630b 3459 BUG_ON(sh->batch_head);
7f0da59b 3460 clear_bit(STRIPE_SYNCING, &sh->state);
f8dfcffd
N		 3461 if (test_and_clear_bit(R5_Overlap, &sh->dev[sh->pd_idx].flags))
3462 wake_up(&conf->wait_for_overlap);
7f0da59b 3463 s->syncing = 0;
9a3e1101 3464 s->replacing = 0;
7f0da59b 3465 /* There is nothing more to do for sync/check/repair.
18b9837e
N		 3466 * Don't even need to abort as that is handled elsewhere
3467 * if needed, and not always wanted e.g. if there is a known
3468 * bad block here.
9a3e1101 3469 * For recover/replace we need to record a bad block on all
7f0da59b
N		 3470 * non-sync devices, or abort the recovery
3471 */
18b9837e
N		 3472 if (test_bit(MD_RECOVERY_RECOVER, &conf->mddev->recovery)) {
3473 /* During recovery devices cannot be removed, so
3474 * locking and refcounting of rdevs is not needed
3475 */
e50d3992 3476 rcu_read_lock();
18b9837e 3477 for (i = 0; i < conf->raid_disks; i++) {
e50d3992 3478 struct md_rdev *rdev = rcu_dereference(conf->disks[i].rdev);
18b9837e
N		 3479 if (rdev
3480 && !test_bit(Faulty, &rdev->flags)
3481 && !test_bit(In_sync, &rdev->flags)
3482 && !rdev_set_badblocks(rdev, sh->sector,
3483 STRIPE_SECTORS, 0))
3484 abort = 1;
e50d3992 3485 rdev = rcu_dereference(conf->disks[i].replacement);
18b9837e
N		 3486 if (rdev
3487 && !test_bit(Faulty, &rdev->flags)
3488 && !test_bit(In_sync, &rdev->flags)
3489 && !rdev_set_badblocks(rdev, sh->sector,
3490 STRIPE_SECTORS, 0))
3491 abort = 1;
3492 }
e50d3992 3493 rcu_read_unlock();
18b9837e
N		 3494 if (abort)
3495 conf->recovery_disabled =
3496 conf->mddev->recovery_disabled;
7f0da59b 3497 }
18b9837e 3498 md_done_sync(conf->mddev, STRIPE_SECTORS, !abort);
7f0da59b
N		 3499}
3500
9a3e1101
N		 3501static int want_replace(struct stripe_head *sh, int disk_idx)
3502{
3503 struct md_rdev *rdev;
3504 int rv = 0;
3f232d6a
N		 3505
3506 rcu_read_lock();
3507 rdev = rcu_dereference(sh->raid_conf->disks[disk_idx].replacement);
9a3e1101
N		 3508 if (rdev
3509 && !test_bit(Faulty, &rdev->flags)
3510 && !test_bit(In_sync, &rdev->flags)
3511 && (rdev->recovery_offset <= sh->sector
3512 || rdev->mddev->recovery_cp <= sh->sector))
3513 rv = 1;
3f232d6a 3514 rcu_read_unlock();
9a3e1101
N		 3515 return rv;
3516}
3517
2c58f06e
N		 3518static int need_this_block(struct stripe_head *sh, struct stripe_head_state *s,
3519 int disk_idx, int disks)
a4456856 3520{
5599becc 3521 struct r5dev *dev = &sh->dev[disk_idx];
f2b3b44d
N		 3522 struct r5dev *fdev[2] = { &sh->dev[s->failed_num[0]],
3523 &sh->dev[s->failed_num[1]] };
ea664c82 3524 int i;
5599becc 3525
a79cfe12
N		 3526
3527 if (test_bit(R5_LOCKED, &dev->flags) ||
3528 test_bit(R5_UPTODATE, &dev->flags))
3529 /* No point reading this as we already have it or have
3530 * decided to get it.
3531 */
3532 return 0;
3533
3534 if (dev->toread ||
3535 (dev->towrite && !test_bit(R5_OVERWRITE, &dev->flags)))
3536 /* We need this block to directly satisfy a request */
3537 return 1;
3538
3539 if (s->syncing || s->expanding ||
3540 (s->replacing && want_replace(sh, disk_idx)))
3541 /* When syncing, or expanding we read everything.
3542 * When replacing, we need the replaced block.
3543 */
3544 return 1;
3545
3546 if ((s->failed >= 1 && fdev[0]->toread) ||
3547 (s->failed >= 2 && fdev[1]->toread))
3548 /* If we want to read from a failed device, then
3549 * we need to actually read every other device.
3550 */
3551 return 1;
3552
a9d56950
N		 3553 /* Sometimes neither read-modify-write nor reconstruct-write
3554 * cycles can work. In those cases we read every block we
3555 * can. Then the parity-update is certain to have enough to
3556 * work with.
3557 * This can only be a problem when we need to write something,
3558 * and some device has failed. If either of those tests
3559 * fail we need look no further.
3560 */
3561 if (!s->failed || !s->to_write)
3562 return 0;
3563
3564 if (test_bit(R5_Insync, &dev->flags) &&
3565 !test_bit(STRIPE_PREREAD_ACTIVE, &sh->state))
3566 /* Pre-reads at not permitted until after short delay
3567 * to gather multiple requests. However if this
3560741e 3568 * device is no Insync, the block could only be computed
a9d56950
N		 3569 * and there is no need to delay that.
3570 */
3571 return 0;
ea664c82 3572
36707bb2 3573 for (i = 0; i < s->failed && i < 2; i++) {
ea664c82
N		 3574 if (fdev[i]->towrite &&
3575 !test_bit(R5_UPTODATE, &fdev[i]->flags) &&
3576 !test_bit(R5_OVERWRITE, &fdev[i]->flags))
3577 /* If we have a partial write to a failed
3578 * device, then we will need to reconstruct
3579 * the content of that device, so all other
3580 * devices must be read.
3581 */
3582 return 1;
3583 }
3584
3585 /* If we are forced to do a reconstruct-write, either because
3586 * the current RAID6 implementation only supports that, or
3560741e 3587 * because parity cannot be trusted and we are currently
ea664c82
N		 3588 * recovering it, there is extra need to be careful.
3589 * If one of the devices that we would need to read, because
3590 * it is not being overwritten (and maybe not written at all)
3591 * is missing/faulty, then we need to read everything we can.
3592 */
3593 if (sh->raid_conf->level != 6 &&
3594 sh->sector < sh->raid_conf->mddev->recovery_cp)
3595 /* reconstruct-write isn't being forced */
3596 return 0;
36707bb2 3597 for (i = 0; i < s->failed && i < 2; i++) {
10d82c5f
N		 3598 if (s->failed_num[i] != sh->pd_idx &&
3599 s->failed_num[i] != sh->qd_idx &&
3600 !test_bit(R5_UPTODATE, &fdev[i]->flags) &&
ea664c82
N		 3601 !test_bit(R5_OVERWRITE, &fdev[i]->flags))
3602 return 1;
3603 }
3604
2c58f06e
N		 3605 return 0;
3606}
3607
ba02684d
SL		 3608/* fetch_block - checks the given member device to see if its data needs
3609 * to be read or computed to satisfy a request.
3610 *
3611 * Returns 1 when no more member devices need to be checked, otherwise returns
3612 * 0 to tell the loop in handle_stripe_fill to continue
3613 */
2c58f06e
N		 3614static int fetch_block(struct stripe_head *sh, struct stripe_head_state *s,
3615 int disk_idx, int disks)
3616{
3617 struct r5dev *dev = &sh->dev[disk_idx];
3618
3619 /* is the data in this block needed, and can we get it? */
3620 if (need_this_block(sh, s, disk_idx, disks)) {
5599becc
YT		 3621 /* we would like to get this block, possibly by computing it,
3622 * otherwise read it if the backing disk is insync
3623 */
3624 BUG_ON(test_bit(R5_Wantcompute, &dev->flags));
3625 BUG_ON(test_bit(R5_Wantread, &dev->flags));
b0c783b3 3626 BUG_ON(sh->batch_head);
7471fb77
N		 3627
3628 /*
3629 * In the raid6 case if the only non-uptodate disk is P
3630 * then we already trusted P to compute the other failed
3631 * drives. It is safe to compute rather than re-read P.
3632 * In other cases we only compute blocks from failed
3633 * devices, otherwise check/repair might fail to detect
3634 * a real inconsistency.
3635 */
3636
5599becc 3637 if ((s->uptodate == disks - 1) &&
7471fb77 3638 ((sh->qd_idx >= 0 && sh->pd_idx == disk_idx) ||
f2b3b44d 3639 (s->failed && (disk_idx == s->failed_num[0] ||
7471fb77 3640 disk_idx == s->failed_num[1])))) {
5599becc
YT		 3641 /* have disk failed, and we're requested to fetch it;
3642 * do compute it
a4456856 3643 */
5599becc
YT		 3644 pr_debug("Computing stripe %llu block %d\n",
3645 (unsigned long long)sh->sector, disk_idx);
3646 set_bit(STRIPE_COMPUTE_RUN, &sh->state);
3647 set_bit(STRIPE_OP_COMPUTE_BLK, &s->ops_request);
3648 set_bit(R5_Wantcompute, &dev->flags);
3649 sh->ops.target = disk_idx;
3650 sh->ops.target2 = -1; /* no 2nd target */
3651 s->req_compute = 1;
93b3dbce
N		 3652 /* Careful: from this point on 'uptodate' is in the eye
3653 * of raid_run_ops which services 'compute' operations
3654 * before writes. R5_Wantcompute flags a block that will
3655 * be R5_UPTODATE by the time it is needed for a
3656 * subsequent operation.
3657 */
5599becc
YT		 3658 s->uptodate++;
3659 return 1;
3660 } else if (s->uptodate == disks-2 && s->failed >= 2) {
3661 /* Computing 2-failure is *very* expensive; only
3662 * do it if failed >= 2
3663 */
3664 int other;
3665 for (other = disks; other--; ) {
3666 if (other == disk_idx)
3667 continue;
3668 if (!test_bit(R5_UPTODATE,
3669 &sh->dev[other].flags))
3670 break;
a4456856 3671 }
5599becc
YT		 3672 BUG_ON(other < 0);
3673 pr_debug("Computing stripe %llu blocks %d,%d\n",
3674 (unsigned long long)sh->sector,
3675 disk_idx, other);
3676 set_bit(STRIPE_COMPUTE_RUN, &sh->state);
3677 set_bit(STRIPE_OP_COMPUTE_BLK, &s->ops_request);
3678 set_bit(R5_Wantcompute, &sh->dev[disk_idx].flags);
3679 set_bit(R5_Wantcompute, &sh->dev[other].flags);
3680 sh->ops.target = disk_idx;
3681 sh->ops.target2 = other;
3682 s->uptodate += 2;
3683 s->req_compute = 1;
3684 return 1;
3685 } else if (test_bit(R5_Insync, &dev->flags)) {
3686 set_bit(R5_LOCKED, &dev->flags);
3687 set_bit(R5_Wantread, &dev->flags);
3688 s->locked++;
3689 pr_debug("Reading block %d (sync=%d)\n",
3690 disk_idx, s->syncing);
a4456856
DW		 3691 }
3692 }
5599becc
YT		 3693
3694 return 0;
3695}
3696
3697/**
93b3dbce 3698 * handle_stripe_fill - read or compute data to satisfy pending requests.
5599becc 3699 */
93b3dbce
N		 3700static void handle_stripe_fill(struct stripe_head *sh,
3701 struct stripe_head_state *s,
3702 int disks)
5599becc
YT		 3703{
3704 int i;
3705
3706 /* look for blocks to read/compute, skip this if a compute
3707 * is already in flight, or if the stripe contents are in the
3708 * midst of changing due to a write
3709 */
3710 if (!test_bit(STRIPE_COMPUTE_RUN, &sh->state) && !sh->check_state &&
07e83364
SL		 3711 !sh->reconstruct_state) {
3712
3713 /*
3714 * For degraded stripe with data in journal, do not handle
3715 * read requests yet, instead, flush the stripe to raid
3716 * disks first, this avoids handling complex rmw of write
3717 * back cache (prexor with orig_page, and then xor with
3718 * page) in the read path
3719 */
3720 if (s->injournal && s->failed) {
3721 if (test_bit(STRIPE_R5C_CACHING, &sh->state))
3722 r5c_make_stripe_write_out(sh);
3723 goto out;
3724 }
3725
5599becc 3726 for (i = disks; i--; )
93b3dbce 3727 if (fetch_block(sh, s, i, disks))
5599becc 3728 break;
07e83364
SL		 3729 }
3730out:
a4456856
DW		 3731 set_bit(STRIPE_HANDLE, &sh->state);
3732}
3733
787b76fa
N		 3734static void break_stripe_batch_list(struct stripe_head *head_sh,
3735 unsigned long handle_flags);
1fe797e6 3736/* handle_stripe_clean_event
a4456856
DW		 3737 * any written block on an uptodate or failed drive can be returned.
3738 * Note that if we 'wrote' to a failed drive, it will be UPTODATE, but
3739 * never LOCKED, so we don't need to test 'failed' directly.
3740 */
d1688a6d 3741static void handle_stripe_clean_event(struct r5conf *conf,
bd83d0a2 3742 struct stripe_head *sh, int disks)
a4456856
DW		 3743{
3744 int i;
3745 struct r5dev *dev;
f8dfcffd 3746 int discard_pending = 0;
59fc630b 3747 struct stripe_head *head_sh = sh;
3748 bool do_endio = false;
a4456856
DW		 3749
3750 for (i = disks; i--; )
3751 if (sh->dev[i].written) {
3752 dev = &sh->dev[i];
3753 if (!test_bit(R5_LOCKED, &dev->flags) &&
9e444768 3754 (test_bit(R5_UPTODATE, &dev->flags) ||
d592a996
SL		 3755 test_bit(R5_Discard, &dev->flags) ||
3756 test_bit(R5_SkipCopy, &dev->flags))) {
a4456856
DW		 3757 /* We can return any write requests */
3758 struct bio *wbi, *wbi2;
45b4233c 3759 pr_debug("Return write for disc %d\n", i);
ca64cae9
N		 3760 if (test_and_clear_bit(R5_Discard, &dev->flags))
3761 clear_bit(R5_UPTODATE, &dev->flags);
d592a996
SL		 3762 if (test_and_clear_bit(R5_SkipCopy, &dev->flags)) {
3763 WARN_ON(test_bit(R5_UPTODATE, &dev->flags));
d592a996 3764 }
59fc630b 3765 do_endio = true;
3766
3767returnbi:
3768 dev->page = dev->orig_page;
a4456856
DW		 3769 wbi = dev->written;
3770 dev->written = NULL;
4f024f37 3771 while (wbi && wbi->bi_iter.bi_sector <
a4456856
DW		 3772 dev->sector + STRIPE_SECTORS) {
3773 wbi2 = r5_next_bio(wbi, dev->sector);
49728050 3774 md_write_end(conf->mddev);
016c76ac 3775 bio_endio(wbi);
a4456856
DW		 3776 wbi = wbi2;
3777 }
e64e4018
AS		 3778 md_bitmap_endwrite(conf->mddev->bitmap, sh->sector,
3779 STRIPE_SECTORS,
3780 !test_bit(STRIPE_DEGRADED, &sh->state),
3781 0);
59fc630b 3782 if (head_sh->batch_head) {
3783 sh = list_first_entry(&sh->batch_list,
3784 struct stripe_head,
3785 batch_list);
3786 if (sh != head_sh) {
3787 dev = &sh->dev[i];
3788 goto returnbi;
3789 }
3790 }
3791 sh = head_sh;
3792 dev = &sh->dev[i];
f8dfcffd
N		 3793 } else if (test_bit(R5_Discard, &dev->flags))
3794 discard_pending = 1;
3795 }
f6bed0ef 3796
ff875738 3797 log_stripe_write_finished(sh);
0576b1c6 3798
f8dfcffd
N		 3799 if (!discard_pending &&
3800 test_bit(R5_Discard, &sh->dev[sh->pd_idx].flags)) {
b8a9d66d 3801 int hash;
f8dfcffd
N		 3802 clear_bit(R5_Discard, &sh->dev[sh->pd_idx].flags);
3803 clear_bit(R5_UPTODATE, &sh->dev[sh->pd_idx].flags);
3804 if (sh->qd_idx >= 0) {
3805 clear_bit(R5_Discard, &sh->dev[sh->qd_idx].flags);
3806 clear_bit(R5_UPTODATE, &sh->dev[sh->qd_idx].flags);
3807 }
3808 /* now that discard is done we can proceed with any sync */
3809 clear_bit(STRIPE_DISCARD, &sh->state);
d47648fc
SL		 3810 /*
3811 * SCSI discard will change some bio fields and the stripe has
3812 * no updated data, so remove it from hash list and the stripe
3813 * will be reinitialized
3814 */
59fc630b 3815unhash:
b8a9d66d
RG		 3816 hash = sh->hash_lock_index;
3817 spin_lock_irq(conf->hash_locks + hash);
d47648fc 3818 remove_hash(sh);
b8a9d66d 3819 spin_unlock_irq(conf->hash_locks + hash);
59fc630b 3820 if (head_sh->batch_head) {
3821 sh = list_first_entry(&sh->batch_list,
3822 struct stripe_head, batch_list);
3823 if (sh != head_sh)
3824 goto unhash;
3825 }
59fc630b 3826 sh = head_sh;
3827
f8dfcffd
N		 3828 if (test_bit(STRIPE_SYNC_REQUESTED, &sh->state))
3829 set_bit(STRIPE_HANDLE, &sh->state);
3830
3831 }
8b3e6cdc
DW		 3832
3833 if (test_and_clear_bit(STRIPE_FULL_WRITE, &sh->state))
3834 if (atomic_dec_and_test(&conf->pending_full_writes))
3835 md_wakeup_thread(conf->mddev->thread);
59fc630b 3836
787b76fa
N		 3837 if (head_sh->batch_head && do_endio)
3838 break_stripe_batch_list(head_sh, STRIPE_EXPAND_SYNC_FLAGS);
a4456856
DW		 3839}
3840
86aa1397
SL		 3841/*
3842 * For RMW in write back cache, we need extra page in prexor to store the
3843 * old data. This page is stored in dev->orig_page.
3844 *
3845 * This function checks whether we have data for prexor. The exact logic
3846 * is:
3847 * R5_UPTODATE && (!R5_InJournal || R5_OrigPageUPTDODATE)
3848 */
3849static inline bool uptodate_for_rmw(struct r5dev *dev)
3850{
3851 return (test_bit(R5_UPTODATE, &dev->flags)) &&
3852 (!test_bit(R5_InJournal, &dev->flags) ||
3853 test_bit(R5_OrigPageUPTDODATE, &dev->flags));
3854}
3855
d7bd398e
SL		 3856static int handle_stripe_dirtying(struct r5conf *conf,
3857 struct stripe_head *sh,
3858 struct stripe_head_state *s,
3859 int disks)
a4456856
DW		 3860{
3861 int rmw = 0, rcw = 0, i;
a7854487
AL		 3862 sector_t recovery_cp = conf->mddev->recovery_cp;
3863
584acdd4 3864 /* Check whether resync is now happening or should start.
a7854487
AL		 3865 * If yes, then the array is dirty (after unclean shutdown or
3866 * initial creation), so parity in some stripes might be inconsistent.
3867 * In this case, we need to always do reconstruct-write, to ensure
3868 * that in case of drive failure or read-error correction, we
3869 * generate correct data from the parity.
3870 */
584acdd4 3871 if (conf->rmw_level == PARITY_DISABLE_RMW ||
26ac1073
N		 3872 (recovery_cp < MaxSector && sh->sector >= recovery_cp &&
3873 s->failed == 0)) {
a7854487 3874 /* Calculate the real rcw later - for now make it
c8ac1803
N		 3875 * look like rcw is cheaper
3876 */
3877 rcw = 1; rmw = 2;
584acdd4
MS		 3878 pr_debug("force RCW rmw_level=%u, recovery_cp=%llu sh->sector=%llu\n",
3879 conf->rmw_level, (unsigned long long)recovery_cp,
a7854487 3880 (unsigned long long)sh->sector);
c8ac1803 3881 } else for (i = disks; i--; ) {
a4456856
DW		 3882 /* would I have to read this buffer for read_modify_write */
3883 struct r5dev *dev = &sh->dev[i];
39b99586 3884 if (((dev->towrite && !delay_towrite(conf, dev, s)) ||
07e83364 3885 i == sh->pd_idx || i == sh->qd_idx ||
1e6d690b 3886 test_bit(R5_InJournal, &dev->flags)) &&
a4456856 3887 !test_bit(R5_LOCKED, &dev->flags) &&
86aa1397 3888 !(uptodate_for_rmw(dev) ||
f38e1219 3889 test_bit(R5_Wantcompute, &dev->flags))) {
a4456856
DW		 3890 if (test_bit(R5_Insync, &dev->flags))
3891 rmw++;
3892 else
3893 rmw += 2*disks; /* cannot read it */
3894 }
3895 /* Would I have to read this buffer for reconstruct_write */
584acdd4
MS		 3896 if (!test_bit(R5_OVERWRITE, &dev->flags) &&
3897 i != sh->pd_idx && i != sh->qd_idx &&
a4456856 3898 !test_bit(R5_LOCKED, &dev->flags) &&
f38e1219 3899 !(test_bit(R5_UPTODATE, &dev->flags) ||
1e6d690b 3900 test_bit(R5_Wantcompute, &dev->flags))) {
67f45548
N		 3901 if (test_bit(R5_Insync, &dev->flags))
3902 rcw++;
a4456856
DW		 3903 else
3904 rcw += 2*disks;
3905 }
3906 }
1e6d690b 3907
39b99586
SL		 3908 pr_debug("for sector %llu state 0x%lx, rmw=%d rcw=%d\n",
3909 (unsigned long long)sh->sector, sh->state, rmw, rcw);
a4456856 3910 set_bit(STRIPE_HANDLE, &sh->state);
41257580 3911 if ((rmw < rcw || (rmw == rcw && conf->rmw_level == PARITY_PREFER_RMW)) && rmw > 0) {
a4456856 3912 /* prefer read-modify-write, but need to get some data */
e3620a3a
JB		 3913 if (conf->mddev->queue)
3914 blk_add_trace_msg(conf->mddev->queue,
3915 "raid5 rmw %llu %d",
3916 (unsigned long long)sh->sector, rmw);
a4456856
DW		 3917 for (i = disks; i--; ) {
3918 struct r5dev *dev = &sh->dev[i];
1e6d690b
SL		 3919 if (test_bit(R5_InJournal, &dev->flags) &&
3920 dev->page == dev->orig_page &&
3921 !test_bit(R5_LOCKED, &sh->dev[sh->pd_idx].flags)) {
3922 /* alloc page for prexor */
d7bd398e
SL		 3923 struct page *p = alloc_page(GFP_NOIO);
3924
3925 if (p) {
3926 dev->orig_page = p;
3927 continue;
3928 }
3929
3930 /*
3931 * alloc_page() failed, try use
3932 * disk_info->extra_page
3933 */
3934 if (!test_and_set_bit(R5C_EXTRA_PAGE_IN_USE,
3935 &conf->cache_state)) {
3936 r5c_use_extra_page(sh);
3937 break;
3938 }
1e6d690b 3939
d7bd398e
SL		 3940 /* extra_page in use, add to delayed_list */
3941 set_bit(STRIPE_DELAYED, &sh->state);
3942 s->waiting_extra_page = 1;
3943 return -EAGAIN;
1e6d690b 3944 }
d7bd398e 3945 }
1e6d690b 3946
d7bd398e
SL		 3947 for (i = disks; i--; ) {
3948 struct r5dev *dev = &sh->dev[i];
39b99586 3949 if (((dev->towrite && !delay_towrite(conf, dev, s)) ||
1e6d690b
SL		 3950 i == sh->pd_idx || i == sh->qd_idx ||
3951 test_bit(R5_InJournal, &dev->flags)) &&
a4456856 3952 !test_bit(R5_LOCKED, &dev->flags) &&
86aa1397 3953 !(uptodate_for_rmw(dev) ||
1e6d690b 3954 test_bit(R5_Wantcompute, &dev->flags)) &&
a4456856 3955 test_bit(R5_Insync, &dev->flags)) {
67f45548
N		 3956 if (test_bit(STRIPE_PREREAD_ACTIVE,
3957 &sh->state)) {
3958 pr_debug("Read_old block %d for r-m-w\n",
3959 i);
a4456856
DW		 3960 set_bit(R5_LOCKED, &dev->flags);
3961 set_bit(R5_Wantread, &dev->flags);
3962 s->locked++;
3963 } else {
3964 set_bit(STRIPE_DELAYED, &sh->state);
3965 set_bit(STRIPE_HANDLE, &sh->state);
3966 }
3967 }
3968 }
a9add5d9 3969 }
41257580 3970 if ((rcw < rmw || (rcw == rmw && conf->rmw_level != PARITY_PREFER_RMW)) && rcw > 0) {
a4456856 3971 /* want reconstruct write, but need to get some data */
a9add5d9 3972 int qread =0;
c8ac1803 3973 rcw = 0;
a4456856
DW		 3974 for (i = disks; i--; ) {
3975 struct r5dev *dev = &sh->dev[i];
3976 if (!test_bit(R5_OVERWRITE, &dev->flags) &&
c8ac1803 3977 i != sh->pd_idx && i != sh->qd_idx &&
a4456856 3978 !test_bit(R5_LOCKED, &dev->flags) &&
f38e1219 3979 !(test_bit(R5_UPTODATE, &dev->flags) ||
c8ac1803
N		 3980 test_bit(R5_Wantcompute, &dev->flags))) {
3981 rcw++;
67f45548
N		 3982 if (test_bit(R5_Insync, &dev->flags) &&
3983 test_bit(STRIPE_PREREAD_ACTIVE,
3984 &sh->state)) {
45b4233c 3985 pr_debug("Read_old block "
a4456856
DW		 3986 "%d for Reconstruct\n", i);
3987 set_bit(R5_LOCKED, &dev->flags);
3988 set_bit(R5_Wantread, &dev->flags);
3989 s->locked++;
a9add5d9 3990 qread++;
a4456856
DW		 3991 } else {
3992 set_bit(STRIPE_DELAYED, &sh->state);
3993 set_bit(STRIPE_HANDLE, &sh->state);
3994 }
3995 }
3996 }
e3620a3a 3997 if (rcw && conf->mddev->queue)
a9add5d9
N		 3998 blk_add_trace_msg(conf->mddev->queue, "raid5 rcw %llu %d %d %d",
3999 (unsigned long long)sh->sector,
4000 rcw, qread, test_bit(STRIPE_DELAYED, &sh->state));
c8ac1803 4001 }
b1b02fe9
N		 4002
4003 if (rcw > disks && rmw > disks &&
4004 !test_bit(STRIPE_PREREAD_ACTIVE, &sh->state))
4005 set_bit(STRIPE_DELAYED, &sh->state);
4006
a4456856
DW		 4007 /* now if nothing is locked, and if we have enough data,
4008 * we can start a write request
4009 */
f38e1219
DW		 4010 /* since handle_stripe can be called at any time we need to handle the
4011 * case where a compute block operation has been submitted and then a
ac6b53b6
DW		 4012 * subsequent call wants to start a write request. raid_run_ops only
4013 * handles the case where compute block and reconstruct are requested
f38e1219
DW		 4014 * simultaneously. If this is not the case then new writes need to be
4015 * held off until the compute completes.
4016 */
976ea8d4
DW		 4017 if ((s->req_compute || !test_bit(STRIPE_COMPUTE_RUN, &sh->state)) &&
4018 (s->locked == 0 && (rcw == 0 || rmw == 0) &&
1e6d690b 4019 !test_bit(STRIPE_BIT_DELAY, &sh->state)))
c0f7bddb 4020 schedule_reconstruction(sh, s, rcw == 0, 0);
d7bd398e 4021 return 0;
a4456856
DW		 4022}
4023
d1688a6d 4024static void handle_parity_checks5(struct r5conf *conf, struct stripe_head *sh,
a4456856
DW		 4025 struct stripe_head_state *s, int disks)
4026{
ecc65c9b 4027 struct r5dev *dev = NULL;
bd2ab670 4028
59fc630b 4029 BUG_ON(sh->batch_head);
a4456856 4030 set_bit(STRIPE_HANDLE, &sh->state);
e89f8962 4031
ecc65c9b
DW		 4032 switch (sh->check_state) {
4033 case check_state_idle:
4034 /* start a new check operation if there are no failures */
bd2ab670 4035 if (s->failed == 0) {
bd2ab670 4036 BUG_ON(s->uptodate != disks);
ecc65c9b
DW		 4037 sh->check_state = check_state_run;
4038 set_bit(STRIPE_OP_CHECK, &s->ops_request);
bd2ab670 4039 clear_bit(R5_UPTODATE, &sh->dev[sh->pd_idx].flags);
bd2ab670 4040 s->uptodate--;
ecc65c9b 4041 break;
bd2ab670 4042 }
f2b3b44d 4043 dev = &sh->dev[s->failed_num[0]];
ecc65c9b
DW		 4044 /* fall through */
4045 case check_state_compute_result:
4046 sh->check_state = check_state_idle;
4047 if (!dev)
4048 dev = &sh->dev[sh->pd_idx];
4049
4050 /* check that a write has not made the stripe insync */
4051 if (test_bit(STRIPE_INSYNC, &sh->state))
4052 break;
c8894419 4053
a4456856 4054 /* either failed parity check, or recovery is happening */
a4456856
DW		 4055 BUG_ON(!test_bit(R5_UPTODATE, &dev->flags));
4056 BUG_ON(s->uptodate != disks);
4057
4058 set_bit(R5_LOCKED, &dev->flags);
ecc65c9b 4059 s->locked++;
a4456856 4060 set_bit(R5_Wantwrite, &dev->flags);
830ea016 4061
a4456856 4062 clear_bit(STRIPE_DEGRADED, &sh->state);
a4456856 4063 set_bit(STRIPE_INSYNC, &sh->state);
ecc65c9b
DW		 4064 break;
4065 case check_state_run:
4066 break; /* we will be called again upon completion */
4067 case check_state_check_result:
4068 sh->check_state = check_state_idle;
4069
4070 /* if a failure occurred during the check operation, leave
4071 * STRIPE_INSYNC not set and let the stripe be handled again
4072 */
4073 if (s->failed)
4074 break;
4075
4076 /* handle a successful check operation, if parity is correct
4077 * we are done. Otherwise update the mismatch count and repair
4078 * parity if !MD_RECOVERY_CHECK
4079 */
ad283ea4 4080 if ((sh->ops.zero_sum_result & SUM_CHECK_P_RESULT) == 0)
ecc65c9b
DW		 4081 /* parity is correct (on disc,
4082 * not in buffer any more)
4083 */
4084 set_bit(STRIPE_INSYNC, &sh->state);
4085 else {
7f7583d4 4086 atomic64_add(STRIPE_SECTORS, &conf->mddev->resync_mismatches);
e1539036 4087 if (test_bit(MD_RECOVERY_CHECK, &conf->mddev->recovery)) {
ecc65c9b
DW		 4088 /* don't try to repair!! */
4089 set_bit(STRIPE_INSYNC, &sh->state);
e1539036
N		 4090 pr_warn_ratelimited("%s: mismatch sector in range "
4091 "%llu-%llu\n", mdname(conf->mddev),
4092 (unsigned long long) sh->sector,
4093 (unsigned long long) sh->sector +
4094 STRIPE_SECTORS);
4095 } else {
ecc65c9b 4096 sh->check_state = check_state_compute_run;
976ea8d4 4097 set_bit(STRIPE_COMPUTE_RUN, &sh->state);
ecc65c9b
DW		 4098 set_bit(STRIPE_OP_COMPUTE_BLK, &s->ops_request);
4099 set_bit(R5_Wantcompute,
4100 &sh->dev[sh->pd_idx].flags);
4101 sh->ops.target = sh->pd_idx;
ac6b53b6 4102 sh->ops.target2 = -1;
ecc65c9b
DW		 4103 s->uptodate++;
4104 }
4105 }
4106 break;
4107 case check_state_compute_run:
4108 break;
4109 default:
cc6167b4 4110 pr_err("%s: unknown check_state: %d sector: %llu\n",
ecc65c9b
DW		 4111 __func__, sh->check_state,
4112 (unsigned long long) sh->sector);
4113 BUG();
a4456856
DW		 4114 }
4115}
4116
d1688a6d 4117static void handle_parity_checks6(struct r5conf *conf, struct stripe_head *sh,
36d1c647 4118 struct stripe_head_state *s,
f2b3b44d 4119 int disks)
a4456856 4120{
a4456856 4121 int pd_idx = sh->pd_idx;
34e04e87 4122 int qd_idx = sh->qd_idx;
d82dfee0 4123 struct r5dev *dev;
a4456856 4124
59fc630b 4125 BUG_ON(sh->batch_head);
a4456856
DW		 4126 set_bit(STRIPE_HANDLE, &sh->state);
4127
4128 BUG_ON(s->failed > 2);
d82dfee0 4129
a4456856
DW		 4130 /* Want to check and possibly repair P and Q.
4131 * However there could be one 'failed' device, in which
4132 * case we can only check one of them, possibly using the
4133 * other to generate missing data
4134 */
4135
d82dfee0
DW		 4136 switch (sh->check_state) {
4137 case check_state_idle:
4138 /* start a new check operation if there are < 2 failures */
f2b3b44d 4139 if (s->failed == s->q_failed) {
d82dfee0 4140 /* The only possible failed device holds Q, so it
a4456856
DW		 4141 * makes sense to check P (If anything else were failed,
4142 * we would have used P to recreate it).
4143 */
d82dfee0 4144 sh->check_state = check_state_run;
a4456856 4145 }
f2b3b44d 4146 if (!s->q_failed && s->failed < 2) {
d82dfee0 4147 /* Q is not failed, and we didn't use it to generate
a4456856
DW		 4148 * anything, so it makes sense to check it
4149 */
d82dfee0
DW		 4150 if (sh->check_state == check_state_run)
4151 sh->check_state = check_state_run_pq;
4152 else
4153 sh->check_state = check_state_run_q;
a4456856 4154 }
a4456856 4155
d82dfee0
DW		 4156 /* discard potentially stale zero_sum_result */
4157 sh->ops.zero_sum_result = 0;
a4456856 4158
d82dfee0
DW		 4159 if (sh->check_state == check_state_run) {
4160 /* async_xor_zero_sum destroys the contents of P */
4161 clear_bit(R5_UPTODATE, &sh->dev[pd_idx].flags);
4162 s->uptodate--;
a4456856 4163 }
d82dfee0
DW		 4164 if (sh->check_state >= check_state_run &&
4165 sh->check_state <= check_state_run_pq) {
4166 /* async_syndrome_zero_sum preserves P and Q, so
4167 * no need to mark them !uptodate here
4168 */
4169 set_bit(STRIPE_OP_CHECK, &s->ops_request);
4170 break;
a4456856
DW		 4171 }
4172
d82dfee0
DW		 4173 /* we have 2-disk failure */
4174 BUG_ON(s->failed != 2);
4175 /* fall through */
4176 case check_state_compute_result:
4177 sh->check_state = check_state_idle;
a4456856 4178
d82dfee0
DW		 4179 /* check that a write has not made the stripe insync */
4180 if (test_bit(STRIPE_INSYNC, &sh->state))
4181 break;
a4456856
DW		 4182
4183 /* now write out any block on a failed drive,
d82dfee0 4184 * or P or Q if they were recomputed
a4456856 4185 */
b2176a1d 4186 dev = NULL;
a4456856 4187 if (s->failed == 2) {
f2b3b44d 4188 dev = &sh->dev[s->failed_num[1]];
a4456856
DW		 4189 s->locked++;
4190 set_bit(R5_LOCKED, &dev->flags);
4191 set_bit(R5_Wantwrite, &dev->flags);
4192 }
4193 if (s->failed >= 1) {
f2b3b44d 4194 dev = &sh->dev[s->failed_num[0]];
a4456856
DW		 4195 s->locked++;
4196 set_bit(R5_LOCKED, &dev->flags);
4197 set_bit(R5_Wantwrite, &dev->flags);
4198 }
d82dfee0 4199 if (sh->ops.zero_sum_result & SUM_CHECK_P_RESULT) {
a4456856
DW		 4200 dev = &sh->dev[pd_idx];
4201 s->locked++;
4202 set_bit(R5_LOCKED, &dev->flags);
4203 set_bit(R5_Wantwrite, &dev->flags);
4204 }
d82dfee0 4205 if (sh->ops.zero_sum_result & SUM_CHECK_Q_RESULT) {
a4456856
DW		 4206 dev = &sh->dev[qd_idx];
4207 s->locked++;
4208 set_bit(R5_LOCKED, &dev->flags);
4209 set_bit(R5_Wantwrite, &dev->flags);
4210 }
b2176a1d
NC		 4211 if (WARN_ONCE(dev && !test_bit(R5_UPTODATE, &dev->flags),
4212 "%s: disk%td not up to date\n",
4213 mdname(conf->mddev),
4214 dev - (struct r5dev *) &sh->dev)) {
4215 clear_bit(R5_LOCKED, &dev->flags);
4216 clear_bit(R5_Wantwrite, &dev->flags);
4217 s->locked--;
4218 }
a4456856
DW		 4219 clear_bit(STRIPE_DEGRADED, &sh->state);
4220
4221 set_bit(STRIPE_INSYNC, &sh->state);
d82dfee0
DW		 4222 break;
4223 case check_state_run:
4224 case check_state_run_q:
4225 case check_state_run_pq:
4226 break; /* we will be called again upon completion */
4227 case check_state_check_result:
4228 sh->check_state = check_state_idle;
4229
4230 /* handle a successful check operation, if parity is correct
4231 * we are done. Otherwise update the mismatch count and repair
4232 * parity if !MD_RECOVERY_CHECK
4233 */
4234 if (sh->ops.zero_sum_result == 0) {
a25d8c32
SL		 4235 /* both parities are correct */
4236 if (!s->failed)
4237 set_bit(STRIPE_INSYNC, &sh->state);
4238 else {
4239 /* in contrast to the raid5 case we can validate
4240 * parity, but still have a failure to write
4241 * back
4242 */
4243 sh->check_state = check_state_compute_result;
4244 /* Returning at this point means that we may go
4245 * off and bring p and/or q uptodate again so
4246 * we make sure to check zero_sum_result again
4247 * to verify if p or q need writeback
4248 */
4249 }
d82dfee0 4250 } else {
7f7583d4 4251 atomic64_add(STRIPE_SECTORS, &conf->mddev->resync_mismatches);
e1539036 4252 if (test_bit(MD_RECOVERY_CHECK, &conf->mddev->recovery)) {
d82dfee0
DW		 4253 /* don't try to repair!! */
4254 set_bit(STRIPE_INSYNC, &sh->state);
e1539036
N		 4255 pr_warn_ratelimited("%s: mismatch sector in range "
4256 "%llu-%llu\n", mdname(conf->mddev),
4257 (unsigned long long) sh->sector,
4258 (unsigned long long) sh->sector +
4259 STRIPE_SECTORS);
4260 } else {
d82dfee0
DW		 4261 int *target = &sh->ops.target;
4262
4263 sh->ops.target = -1;
4264 sh->ops.target2 = -1;
4265 sh->check_state = check_state_compute_run;
4266 set_bit(STRIPE_COMPUTE_RUN, &sh->state);
4267 set_bit(STRIPE_OP_COMPUTE_BLK, &s->ops_request);
4268 if (sh->ops.zero_sum_result & SUM_CHECK_P_RESULT) {
4269 set_bit(R5_Wantcompute,
4270 &sh->dev[pd_idx].flags);
4271 *target = pd_idx;
4272 target = &sh->ops.target2;
4273 s->uptodate++;
4274 }
4275 if (sh->ops.zero_sum_result & SUM_CHECK_Q_RESULT) {
4276 set_bit(R5_Wantcompute,
4277 &sh->dev[qd_idx].flags);
4278 *target = qd_idx;
4279 s->uptodate++;
4280 }
4281 }
4282 }
4283 break;
4284 case check_state_compute_run:
4285 break;
4286 default:
cc6167b4
N		 4287 pr_warn("%s: unknown check_state: %d sector: %llu\n",
4288 __func__, sh->check_state,
4289 (unsigned long long) sh->sector);
d82dfee0 4290 BUG();
a4456856
DW		 4291 }
4292}
4293
d1688a6d 4294static void handle_stripe_expansion(struct r5conf *conf, struct stripe_head *sh)
a4456856
DW		 4295{
4296 int i;
4297
4298 /* We have read all the blocks in this stripe and now we need to
4299 * copy some of them into a target stripe for expand.
4300 */
f0a50d37 4301 struct dma_async_tx_descriptor *tx = NULL;
59fc630b 4302 BUG_ON(sh->batch_head);
a4456856
DW		 4303 clear_bit(STRIPE_EXPAND_SOURCE, &sh->state);
4304 for (i = 0; i < sh->disks; i++)
34e04e87 4305 if (i != sh->pd_idx && i != sh->qd_idx) {
911d4ee8 4306 int dd_idx, j;
a4456856 4307 struct stripe_head *sh2;
a08abd8c 4308 struct async_submit_ctl submit;
a4456856 4309
6d036f7d 4310 sector_t bn = raid5_compute_blocknr(sh, i, 1);
911d4ee8
N		 4311 sector_t s = raid5_compute_sector(conf, bn, 0,
4312 &dd_idx, NULL);
6d036f7d 4313 sh2 = raid5_get_active_stripe(conf, s, 0, 1, 1);
a4456856
DW		 4314 if (sh2 == NULL)
4315 /* so far only the early blocks of this stripe
4316 * have been requested. When later blocks
4317 * get requested, we will try again
4318 */
4319 continue;
4320 if (!test_bit(STRIPE_EXPANDING, &sh2->state) ||
4321 test_bit(R5_Expanded, &sh2->dev[dd_idx].flags)) {
4322 /* must have already done this block */
6d036f7d 4323 raid5_release_stripe(sh2);
a4456856
DW		 4324 continue;
4325 }
f0a50d37
DW		 4326
4327 /* place all the copies on one channel */
a08abd8c 4328 init_async_submit(&submit, 0, tx, NULL, NULL, NULL);
f0a50d37 4329 tx = async_memcpy(sh2->dev[dd_idx].page,
88ba2aa5 4330 sh->dev[i].page, 0, 0, STRIPE_SIZE,
a08abd8c 4331 &submit);
f0a50d37 4332
a4456856
DW		 4333 set_bit(R5_Expanded, &sh2->dev[dd_idx].flags);
4334 set_bit(R5_UPTODATE, &sh2->dev[dd_idx].flags);
4335 for (j = 0; j < conf->raid_disks; j++)
4336 if (j != sh2->pd_idx &&
86c374ba 4337 j != sh2->qd_idx &&
a4456856
DW		 4338 !test_bit(R5_Expanded, &sh2->dev[j].flags))
4339 break;
4340 if (j == conf->raid_disks) {
4341 set_bit(STRIPE_EXPAND_READY, &sh2->state);
4342 set_bit(STRIPE_HANDLE, &sh2->state);
4343 }
6d036f7d 4344 raid5_release_stripe(sh2);
f0a50d37 4345
a4456856 4346 }
a2e08551 4347 /* done submitting copies, wait for them to complete */
749586b7 4348 async_tx_quiesce(&tx);
a4456856 4349}
1da177e4
LT		 4350
4351/*
4352 * handle_stripe - do things to a stripe.
4353 *
9a3e1101
N		 4354 * We lock the stripe by setting STRIPE_ACTIVE and then examine the
4355 * state of various bits to see what needs to be done.
1da177e4 4356 * Possible results:
9a3e1101
N		 4357 * return some read requests which now have data
4358 * return some write requests which are safely on storage
1da177e4
LT		 4359 * schedule a read on some buffers
4360 * schedule a write of some buffers
4361 * return confirmation of parity correctness
4362 *
1da177e4 4363 */
a4456856 4364
acfe726b 4365static void analyse_stripe(struct stripe_head *sh, struct stripe_head_state *s)
1da177e4 4366{
d1688a6d 4367 struct r5conf *conf = sh->raid_conf;
f416885e 4368 int disks = sh->disks;
474af965
N		 4369 struct r5dev *dev;
4370 int i;
9a3e1101 4371 int do_recovery = 0;
1da177e4 4372
acfe726b
N		 4373 memset(s, 0, sizeof(*s));
4374
dabc4ec6 4375 s->expanding = test_bit(STRIPE_EXPAND_SOURCE, &sh->state) && !sh->batch_head;
4376 s->expanded = test_bit(STRIPE_EXPAND_READY, &sh->state) && !sh->batch_head;
acfe726b
N		 4377 s->failed_num[0] = -1;
4378 s->failed_num[1] = -1;
6e74a9cf 4379 s->log_failed = r5l_log_disk_error(conf);
1da177e4 4380
acfe726b 4381 /* Now to look around and see what can be done */
1da177e4 4382 rcu_read_lock();
16a53ecc 4383 for (i=disks; i--; ) {
3cb03002 4384 struct md_rdev *rdev;
31c176ec
N		 4385 sector_t first_bad;
4386 int bad_sectors;
4387 int is_bad = 0;
acfe726b 4388
16a53ecc 4389 dev = &sh->dev[i];
1da177e4 4390
45b4233c 4391 pr_debug("check %d: state 0x%lx read %p write %p written %p\n",
9a3e1101
N		 4392 i, dev->flags,
4393 dev->toread, dev->towrite, dev->written);
6c0069c0
YT		 4394 /* maybe we can reply to a read
4395 *
4396 * new wantfill requests are only permitted while
4397 * ops_complete_biofill is guaranteed to be inactive
4398 */
4399 if (test_bit(R5_UPTODATE, &dev->flags) && dev->toread &&
4400 !test_bit(STRIPE_BIOFILL_RUN, &sh->state))
4401 set_bit(R5_Wantfill, &dev->flags);
1da177e4 4402
16a53ecc 4403 /* now count some things */
cc94015a
N		 4404 if (test_bit(R5_LOCKED, &dev->flags))
4405 s->locked++;
4406 if (test_bit(R5_UPTODATE, &dev->flags))
4407 s->uptodate++;
2d6e4ecc 4408 if (test_bit(R5_Wantcompute, &dev->flags)) {
cc94015a
N		 4409 s->compute++;
4410 BUG_ON(s->compute > 2);
2d6e4ecc 4411 }
1da177e4 4412
acfe726b 4413 if (test_bit(R5_Wantfill, &dev->flags))
cc94015a 4414 s->to_fill++;
acfe726b 4415 else if (dev->toread)
cc94015a 4416 s->to_read++;
16a53ecc 4417 if (dev->towrite) {
cc94015a 4418 s->to_write++;
16a53ecc 4419 if (!test_bit(R5_OVERWRITE, &dev->flags))
cc94015a 4420 s->non_overwrite++;
16a53ecc 4421 }
a4456856 4422 if (dev->written)
cc94015a 4423 s->written++;
14a75d3e
N		 4424 /* Prefer to use the replacement for reads, but only
4425 * if it is recovered enough and has no bad blocks.
4426 */
4427 rdev = rcu_dereference(conf->disks[i].replacement);
4428 if (rdev && !test_bit(Faulty, &rdev->flags) &&
4429 rdev->recovery_offset >= sh->sector + STRIPE_SECTORS &&
4430 !is_badblock(rdev, sh->sector, STRIPE_SECTORS,
4431 &first_bad, &bad_sectors))
4432 set_bit(R5_ReadRepl, &dev->flags);
4433 else {
e6030cb0 4434 if (rdev && !test_bit(Faulty, &rdev->flags))
9a3e1101 4435 set_bit(R5_NeedReplace, &dev->flags);
e6030cb0
N		 4436 else
4437 clear_bit(R5_NeedReplace, &dev->flags);
14a75d3e
N		 4438 rdev = rcu_dereference(conf->disks[i].rdev);
4439 clear_bit(R5_ReadRepl, &dev->flags);
4440 }
9283d8c5
N		 4441 if (rdev && test_bit(Faulty, &rdev->flags))
4442 rdev = NULL;
31c176ec
N		 4443 if (rdev) {
4444 is_bad = is_badblock(rdev, sh->sector, STRIPE_SECTORS,
4445 &first_bad, &bad_sectors);
4446 if (s->blocked_rdev == NULL
4447 && (test_bit(Blocked, &rdev->flags)
4448 || is_bad < 0)) {
4449 if (is_bad < 0)
4450 set_bit(BlockedBadBlocks,
4451 &rdev->flags);
4452 s->blocked_rdev = rdev;
4453 atomic_inc(&rdev->nr_pending);
4454 }
6bfe0b49 4455 }
415e72d0
N		 4456 clear_bit(R5_Insync, &dev->flags);
4457 if (!rdev)
4458 /* Not in-sync */;
31c176ec
N		 4459 else if (is_bad) {
4460 /* also not in-sync */
18b9837e
N		 4461 if (!test_bit(WriteErrorSeen, &rdev->flags) &&
4462 test_bit(R5_UPTODATE, &dev->flags)) {
31c176ec
N		 4463 /* treat as in-sync, but with a read error
4464 * which we can now try to correct
4465 */
4466 set_bit(R5_Insync, &dev->flags);
4467 set_bit(R5_ReadError, &dev->flags);
4468 }
4469 } else if (test_bit(In_sync, &rdev->flags))
415e72d0 4470 set_bit(R5_Insync, &dev->flags);
30d7a483 4471 else if (sh->sector + STRIPE_SECTORS <= rdev->recovery_offset)
415e72d0 4472 /* in sync if before recovery_offset */
30d7a483
N		 4473 set_bit(R5_Insync, &dev->flags);
4474 else if (test_bit(R5_UPTODATE, &dev->flags) &&
4475 test_bit(R5_Expanded, &dev->flags))
4476 /* If we've reshaped into here, we assume it is Insync.
4477 * We will shortly update recovery_offset to make
4478 * it official.
4479 */
4480 set_bit(R5_Insync, &dev->flags);
4481
1cc03eb9 4482 if (test_bit(R5_WriteError, &dev->flags)) {
14a75d3e
N		 4483 /* This flag does not apply to '.replacement'
4484 * only to .rdev, so make sure to check that*/
4485 struct md_rdev *rdev2 = rcu_dereference(
4486 conf->disks[i].rdev);
4487 if (rdev2 == rdev)
4488 clear_bit(R5_Insync, &dev->flags);
4489 if (rdev2 && !test_bit(Faulty, &rdev2->flags)) {
bc2607f3 4490 s->handle_bad_blocks = 1;
14a75d3e 4491 atomic_inc(&rdev2->nr_pending);
bc2607f3
N		 4492 } else
4493 clear_bit(R5_WriteError, &dev->flags);
4494 }
1cc03eb9 4495 if (test_bit(R5_MadeGood, &dev->flags)) {
14a75d3e
N		 4496 /* This flag does not apply to '.replacement'
4497 * only to .rdev, so make sure to check that*/
4498 struct md_rdev *rdev2 = rcu_dereference(
4499 conf->disks[i].rdev);
4500 if (rdev2 && !test_bit(Faulty, &rdev2->flags)) {
b84db560 4501 s->handle_bad_blocks = 1;
14a75d3e 4502 atomic_inc(&rdev2->nr_pending);
b84db560
N		 4503 } else
4504 clear_bit(R5_MadeGood, &dev->flags);
4505 }
977df362
N		 4506 if (test_bit(R5_MadeGoodRepl, &dev->flags)) {
4507 struct md_rdev *rdev2 = rcu_dereference(
4508 conf->disks[i].replacement);
4509 if (rdev2 && !test_bit(Faulty, &rdev2->flags)) {
4510 s->handle_bad_blocks = 1;
4511 atomic_inc(&rdev2->nr_pending);
4512 } else
4513 clear_bit(R5_MadeGoodRepl, &dev->flags);
4514 }
415e72d0 4515 if (!test_bit(R5_Insync, &dev->flags)) {
16a53ecc
N		 4516 /* The ReadError flag will just be confusing now */
4517 clear_bit(R5_ReadError, &dev->flags);
4518 clear_bit(R5_ReWrite, &dev->flags);
1da177e4 4519 }
415e72d0
N		 4520 if (test_bit(R5_ReadError, &dev->flags))
4521 clear_bit(R5_Insync, &dev->flags);
4522 if (!test_bit(R5_Insync, &dev->flags)) {
cc94015a
N		 4523 if (s->failed < 2)
4524 s->failed_num[s->failed] = i;
4525 s->failed++;
9a3e1101
N		 4526 if (rdev && !test_bit(Faulty, &rdev->flags))
4527 do_recovery = 1;
d63e2fc8
BC		 4528 else if (!rdev) {
4529 rdev = rcu_dereference(
4530 conf->disks[i].replacement);
4531 if (rdev && !test_bit(Faulty, &rdev->flags))
4532 do_recovery = 1;
4533 }
415e72d0 4534 }
2ded3703
SL		 4535
4536 if (test_bit(R5_InJournal, &dev->flags))
4537 s->injournal++;
1e6d690b
SL		 4538 if (test_bit(R5_InJournal, &dev->flags) && dev->written)
4539 s->just_cached++;
1da177e4 4540 }
9a3e1101
N		 4541 if (test_bit(STRIPE_SYNCING, &sh->state)) {
4542 /* If there is a failed device being replaced,
4543 * we must be recovering.
4544 * else if we are after recovery_cp, we must be syncing
c6d2e084 4545 * else if MD_RECOVERY_REQUESTED is set, we also are syncing.
9a3e1101
N		 4546 * else we can only be replacing
4547 * sync and recovery both need to read all devices, and so
4548 * use the same flag.
4549 */
4550 if (do_recovery ||
c6d2e084 4551 sh->sector >= conf->mddev->recovery_cp ||
4552 test_bit(MD_RECOVERY_REQUESTED, &(conf->mddev->recovery)))
9a3e1101
N		 4553 s->syncing = 1;
4554 else
4555 s->replacing = 1;
4556 }
1da177e4 4557 rcu_read_unlock();
cc94015a
N		 4558}
4559
59fc630b 4560static int clear_batch_ready(struct stripe_head *sh)
4561{
b15a9dbd
N		 4562 /* Return '1' if this is a member of batch, or
4563 * '0' if it is a lone stripe or a head which can now be
4564 * handled.
4565 */
59fc630b 4566 struct stripe_head *tmp;
4567 if (!test_and_clear_bit(STRIPE_BATCH_READY, &sh->state))
b15a9dbd 4568 return (sh->batch_head && sh->batch_head != sh);
59fc630b 4569 spin_lock(&sh->stripe_lock);
4570 if (!sh->batch_head) {
4571 spin_unlock(&sh->stripe_lock);
4572 return 0;
4573 }
4574
4575 /*
4576 * this stripe could be added to a batch list before we check
4577 * BATCH_READY, skips it
4578 */
4579 if (sh->batch_head != sh) {
4580 spin_unlock(&sh->stripe_lock);
4581 return 1;
4582 }
4583 spin_lock(&sh->batch_lock);
4584 list_for_each_entry(tmp, &sh->batch_list, batch_list)
4585 clear_bit(STRIPE_BATCH_READY, &tmp->state);
4586 spin_unlock(&sh->batch_lock);
4587 spin_unlock(&sh->stripe_lock);
4588
4589 /*
4590 * BATCH_READY is cleared, no new stripes can be added.
4591 * batch_list can be accessed without lock
4592 */
4593 return 0;
4594}
4595
3960ce79
N		 4596static void break_stripe_batch_list(struct stripe_head *head_sh,
4597 unsigned long handle_flags)
72ac7330 4598{
4e3d62ff 4599 struct stripe_head *sh, *next;
72ac7330 4600 int i;
fb642b92 4601 int do_wakeup = 0;
72ac7330 4602
bb27051f
N		 4603 list_for_each_entry_safe(sh, next, &head_sh->batch_list, batch_list) {
4604
72ac7330 4605 list_del_init(&sh->batch_list);
4606
fb3229d5 4607 WARN_ONCE(sh->state & ((1 << STRIPE_ACTIVE) |
1b956f7a
N		 4608 (1 << STRIPE_SYNCING) |
4609 (1 << STRIPE_REPLACED) |
1b956f7a
N		 4610 (1 << STRIPE_DELAYED) |
4611 (1 << STRIPE_BIT_DELAY) |
4612 (1 << STRIPE_FULL_WRITE) |
4613 (1 << STRIPE_BIOFILL_RUN) |
4614 (1 << STRIPE_COMPUTE_RUN) |
4615 (1 << STRIPE_OPS_REQ_PENDING) |
4616 (1 << STRIPE_DISCARD) |
4617 (1 << STRIPE_BATCH_READY) |
4618 (1 << STRIPE_BATCH_ERR) |
fb3229d5
SL		 4619 (1 << STRIPE_BITMAP_PENDING)),
4620 "stripe state: %lx\n", sh->state);
4621 WARN_ONCE(head_sh->state & ((1 << STRIPE_DISCARD) |
4622 (1 << STRIPE_REPLACED)),
4623 "head stripe state: %lx\n", head_sh->state);
1b956f7a
N		 4624
4625 set_mask_bits(&sh->state, ~(STRIPE_EXPAND_SYNC_FLAGS |
550da24f 4626 (1 << STRIPE_PREREAD_ACTIVE) |
184a09eb
DY		 4627 (1 << STRIPE_DEGRADED) |
4628 (1 << STRIPE_ON_UNPLUG_LIST)),
1b956f7a
N		 4629 head_sh->state & (1 << STRIPE_INSYNC));
4630
72ac7330 4631 sh->check_state = head_sh->check_state;
4632 sh->reconstruct_state = head_sh->reconstruct_state;
448ec638
AC		 4633 spin_lock_irq(&sh->stripe_lock);
4634 sh->batch_head = NULL;
4635 spin_unlock_irq(&sh->stripe_lock);
fb642b92
N		 4636 for (i = 0; i < sh->disks; i++) {
4637 if (test_and_clear_bit(R5_Overlap, &sh->dev[i].flags))
4638 do_wakeup = 1;
72ac7330 4639 sh->dev[i].flags = head_sh->dev[i].flags &
4640 (~((1 << R5_WriteError) | (1 << R5_Overlap)));
fb642b92 4641 }
3960ce79
N		 4642 if (handle_flags == 0 ||
4643 sh->state & handle_flags)
4644 set_bit(STRIPE_HANDLE, &sh->state);
6d036f7d 4645 raid5_release_stripe(sh);
72ac7330 4646 }
fb642b92
N		 4647 spin_lock_irq(&head_sh->stripe_lock);
4648 head_sh->batch_head = NULL;
4649 spin_unlock_irq(&head_sh->stripe_lock);
4650 for (i = 0; i < head_sh->disks; i++)
4651 if (test_and_clear_bit(R5_Overlap, &head_sh->dev[i].flags))
4652 do_wakeup = 1;
3960ce79
N		 4653 if (head_sh->state & handle_flags)
4654 set_bit(STRIPE_HANDLE, &head_sh->state);
fb642b92
N		 4655
4656 if (do_wakeup)
4657 wake_up(&head_sh->raid_conf->wait_for_overlap);
72ac7330 4658}
4659
cc94015a
N		 4660static void handle_stripe(struct stripe_head *sh)
4661{
4662 struct stripe_head_state s;
d1688a6d 4663 struct r5conf *conf = sh->raid_conf;
3687c061 4664 int i;
84789554
N		 4665 int prexor;
4666 int disks = sh->disks;
474af965 4667 struct r5dev *pdev, *qdev;
cc94015a
N		 4668
4669 clear_bit(STRIPE_HANDLE, &sh->state);
257a4b42 4670 if (test_and_set_bit_lock(STRIPE_ACTIVE, &sh->state)) {
cc94015a
N		 4671 /* already being handled, ensure it gets handled
4672 * again when current action finishes */
4673 set_bit(STRIPE_HANDLE, &sh->state);
4674 return;
4675 }
4676
59fc630b 4677 if (clear_batch_ready(sh) ) {
4678 clear_bit_unlock(STRIPE_ACTIVE, &sh->state);
4679 return;
4680 }
4681
4e3d62ff 4682 if (test_and_clear_bit(STRIPE_BATCH_ERR, &sh->state))
3960ce79 4683 break_stripe_batch_list(sh, 0);
72ac7330 4684
dabc4ec6 4685 if (test_bit(STRIPE_SYNC_REQUESTED, &sh->state) && !sh->batch_head) {
f8dfcffd 4686 spin_lock(&sh->stripe_lock);
5ddf0440
SL		 4687 /*
4688 * Cannot process 'sync' concurrently with 'discard'.
4689 * Flush data in r5cache before 'sync'.
4690 */
4691 if (!test_bit(STRIPE_R5C_PARTIAL_STRIPE, &sh->state) &&
4692 !test_bit(STRIPE_R5C_FULL_STRIPE, &sh->state) &&
4693 !test_bit(STRIPE_DISCARD, &sh->state) &&
f8dfcffd
N		 4694 test_and_clear_bit(STRIPE_SYNC_REQUESTED, &sh->state)) {
4695 set_bit(STRIPE_SYNCING, &sh->state);
4696 clear_bit(STRIPE_INSYNC, &sh->state);
f94c0b66 4697 clear_bit(STRIPE_REPLACED, &sh->state);
f8dfcffd
N		 4698 }
4699 spin_unlock(&sh->stripe_lock);
cc94015a
N		 4700 }
4701 clear_bit(STRIPE_DELAYED, &sh->state);
4702
4703 pr_debug("handling stripe %llu, state=%#lx cnt=%d, "
4704 "pd_idx=%d, qd_idx=%d\n, check:%d, reconstruct:%d\n",
4705 (unsigned long long)sh->sector, sh->state,
4706 atomic_read(&sh->count), sh->pd_idx, sh->qd_idx,
4707 sh->check_state, sh->reconstruct_state);
3687c061 4708
acfe726b 4709 analyse_stripe(sh, &s);
c5a31000 4710
b70abcb2
SL		 4711 if (test_bit(STRIPE_LOG_TRAPPED, &sh->state))
4712 goto finish;
4713
16d997b7
N		 4714 if (s.handle_bad_blocks ||
4715 test_bit(MD_SB_CHANGE_PENDING, &conf->mddev->sb_flags)) {
bc2607f3
N		 4716 set_bit(STRIPE_HANDLE, &sh->state);
4717 goto finish;
4718 }
4719
474af965
N		 4720 if (unlikely(s.blocked_rdev)) {
4721 if (s.syncing || s.expanding || s.expanded ||
9a3e1101 4722 s.replacing || s.to_write || s.written) {
474af965
N		 4723 set_bit(STRIPE_HANDLE, &sh->state);
4724 goto finish;
4725 }
4726 /* There is nothing for the blocked_rdev to block */
4727 rdev_dec_pending(s.blocked_rdev, conf->mddev);
4728 s.blocked_rdev = NULL;
4729 }
4730
4731 if (s.to_fill && !test_bit(STRIPE_BIOFILL_RUN, &sh->state)) {
4732 set_bit(STRIPE_OP_BIOFILL, &s.ops_request);
4733 set_bit(STRIPE_BIOFILL_RUN, &sh->state);
4734 }
4735
4736 pr_debug("locked=%d uptodate=%d to_read=%d"
4737 " to_write=%d failed=%d failed_num=%d,%d\n",
4738 s.locked, s.uptodate, s.to_read, s.to_write, s.failed,
4739 s.failed_num[0], s.failed_num[1]);
70d466f7
SL		 4740 /*
4741 * check if the array has lost more than max_degraded devices and,
474af965 4742 * if so, some requests might need to be failed.
70d466f7
SL		 4743 *
4744 * When journal device failed (log_failed), we will only process
4745 * the stripe if there is data need write to raid disks
474af965 4746 */
70d466f7
SL		 4747 if (s.failed > conf->max_degraded ||
4748 (s.log_failed && s.injournal == 0)) {
9a3f530f
N		 4749 sh->check_state = 0;
4750 sh->reconstruct_state = 0;
626f2092 4751 break_stripe_batch_list(sh, 0);
9a3f530f 4752 if (s.to_read+s.to_write+s.written)
bd83d0a2 4753 handle_failed_stripe(conf, sh, &s, disks);
9a3e1101 4754 if (s.syncing + s.replacing)
9a3f530f
N		 4755 handle_failed_sync(conf, sh, &s);
4756 }
474af965 4757
84789554
N		 4758 /* Now we check to see if any write operations have recently
4759 * completed
4760 */
4761 prexor = 0;
4762 if (sh->reconstruct_state == reconstruct_state_prexor_drain_result)
4763 prexor = 1;
4764 if (sh->reconstruct_state == reconstruct_state_drain_result ||
4765 sh->reconstruct_state == reconstruct_state_prexor_drain_result) {
4766 sh->reconstruct_state = reconstruct_state_idle;
4767
4768 /* All the 'written' buffers and the parity block are ready to
4769 * be written back to disk
4770 */
9e444768
SL		 4771 BUG_ON(!test_bit(R5_UPTODATE, &sh->dev[sh->pd_idx].flags) &&
4772 !test_bit(R5_Discard, &sh->dev[sh->pd_idx].flags));
84789554 4773 BUG_ON(sh->qd_idx >= 0 &&
9e444768
SL		 4774 !test_bit(R5_UPTODATE, &sh->dev[sh->qd_idx].flags) &&
4775 !test_bit(R5_Discard, &sh->dev[sh->qd_idx].flags));
84789554
N		 4776 for (i = disks; i--; ) {
4777 struct r5dev *dev = &sh->dev[i];
4778 if (test_bit(R5_LOCKED, &dev->flags) &&
4779 (i == sh->pd_idx || i == sh->qd_idx ||
1e6d690b
SL		 4780 dev->written || test_bit(R5_InJournal,
4781 &dev->flags))) {
84789554
N		 4782 pr_debug("Writing block %d\n", i);
4783 set_bit(R5_Wantwrite, &dev->flags);
4784 if (prexor)
4785 continue;
9c4bdf69
N		 4786 if (s.failed > 1)
4787 continue;
84789554
N		 4788 if (!test_bit(R5_Insync, &dev->flags) ||
4789 ((i == sh->pd_idx || i == sh->qd_idx) &&
4790 s.failed == 0))
4791 set_bit(STRIPE_INSYNC, &sh->state);
4792 }
4793 }
4794 if (test_and_clear_bit(STRIPE_PREREAD_ACTIVE, &sh->state))
4795 s.dec_preread_active = 1;
4796 }
4797
ef5b7c69
N		 4798 /*
4799 * might be able to return some write requests if the parity blocks
4800 * are safe, or on a failed drive
4801 */
4802 pdev = &sh->dev[sh->pd_idx];
4803 s.p_failed = (s.failed >= 1 && s.failed_num[0] == sh->pd_idx)
4804 || (s.failed >= 2 && s.failed_num[1] == sh->pd_idx);
4805 qdev = &sh->dev[sh->qd_idx];
4806 s.q_failed = (s.failed >= 1 && s.failed_num[0] == sh->qd_idx)
4807 || (s.failed >= 2 && s.failed_num[1] == sh->qd_idx)
4808 || conf->level < 6;
4809
4810 if (s.written &&
4811 (s.p_failed || ((test_bit(R5_Insync, &pdev->flags)
4812 && !test_bit(R5_LOCKED, &pdev->flags)
4813 && (test_bit(R5_UPTODATE, &pdev->flags) ||
4814 test_bit(R5_Discard, &pdev->flags))))) &&
4815 (s.q_failed || ((test_bit(R5_Insync, &qdev->flags)
4816 && !test_bit(R5_LOCKED, &qdev->flags)
4817 && (test_bit(R5_UPTODATE, &qdev->flags) ||
4818 test_bit(R5_Discard, &qdev->flags))))))
bd83d0a2 4819 handle_stripe_clean_event(conf, sh, disks);
ef5b7c69 4820
1e6d690b 4821 if (s.just_cached)
bd83d0a2 4822 r5c_handle_cached_data_endio(conf, sh, disks);
ff875738 4823 log_stripe_write_finished(sh);
1e6d690b 4824
ef5b7c69
N		 4825 /* Now we might consider reading some blocks, either to check/generate
4826 * parity, or to satisfy requests
4827 * or to load a block that is being partially written.
4828 */
4829 if (s.to_read || s.non_overwrite
4830 || (conf->level == 6 && s.to_write && s.failed)
4831 || (s.syncing && (s.uptodate + s.compute < disks))
4832 || s.replacing
4833 || s.expanding)
4834 handle_stripe_fill(sh, &s, disks);
4835
2ded3703
SL		 4836 /*
4837 * When the stripe finishes full journal write cycle (write to journal
4838 * and raid disk), this is the clean up procedure so it is ready for
4839 * next operation.
4840 */
4841 r5c_finish_stripe_write_out(conf, sh, &s);
4842
4843 /*
4844 * Now to consider new write requests, cache write back and what else,
4845 * if anything should be read. We do not handle new writes when:
84789554
N		 4846 * 1/ A 'write' operation (copy+xor) is already in flight.
4847 * 2/ A 'check' operation is in flight, as it may clobber the parity
4848 * block.
2ded3703 4849 * 3/ A r5c cache log write is in flight.
84789554 4850 */
2ded3703
SL		 4851
4852 if (!sh->reconstruct_state && !sh->check_state && !sh->log_io) {
4853 if (!r5c_is_writeback(conf->log)) {
4854 if (s.to_write)
4855 handle_stripe_dirtying(conf, sh, &s, disks);
4856 } else { /* write back cache */
4857 int ret = 0;
4858
4859 /* First, try handle writes in caching phase */
4860 if (s.to_write)
4861 ret = r5c_try_caching_write(conf, sh, &s,
4862 disks);
4863 /*
4864 * If caching phase failed: ret == -EAGAIN
4865 * OR
4866 * stripe under reclaim: !caching && injournal
4867 *
4868 * fall back to handle_stripe_dirtying()
4869 */
4870 if (ret == -EAGAIN ||
4871 /* stripe under reclaim: !caching && injournal */
4872 (!test_bit(STRIPE_R5C_CACHING, &sh->state) &&
d7bd398e
SL		 4873 s.injournal > 0)) {
4874 ret = handle_stripe_dirtying(conf, sh, &s,
4875 disks);
4876 if (ret == -EAGAIN)
4877 goto finish;
4878 }
2ded3703
SL		 4879 }
4880 }
84789554
N		 4881
4882 /* maybe we need to check and possibly fix the parity for this stripe
4883 * Any reads will already have been scheduled, so we just see if enough
4884 * data is available. The parity check is held off while parity
4885 * dependent operations are in flight.
4886 */
4887 if (sh->check_state ||
4888 (s.syncing && s.locked == 0 &&
4889 !test_bit(STRIPE_COMPUTE_RUN, &sh->state) &&
4890 !test_bit(STRIPE_INSYNC, &sh->state))) {
4891 if (conf->level == 6)
4892 handle_parity_checks6(conf, sh, &s, disks);
4893 else
4894 handle_parity_checks5(conf, sh, &s, disks);
4895 }
c5a31000 4896
f94c0b66
N		 4897 if ((s.replacing || s.syncing) && s.locked == 0
4898 && !test_bit(STRIPE_COMPUTE_RUN, &sh->state)
4899 && !test_bit(STRIPE_REPLACED, &sh->state)) {
9a3e1101
N		 4900 /* Write out to replacement devices where possible */
4901 for (i = 0; i < conf->raid_disks; i++)
f94c0b66
N		 4902 if (test_bit(R5_NeedReplace, &sh->dev[i].flags)) {
4903 WARN_ON(!test_bit(R5_UPTODATE, &sh->dev[i].flags));
9a3e1101
N		 4904 set_bit(R5_WantReplace, &sh->dev[i].flags);
4905 set_bit(R5_LOCKED, &sh->dev[i].flags);
4906 s.locked++;
4907 }
f94c0b66
N		 4908 if (s.replacing)
4909 set_bit(STRIPE_INSYNC, &sh->state);
4910 set_bit(STRIPE_REPLACED, &sh->state);
9a3e1101
N		 4911 }
4912 if ((s.syncing || s.replacing) && s.locked == 0 &&
f94c0b66 4913 !test_bit(STRIPE_COMPUTE_RUN, &sh->state) &&
9a3e1101 4914 test_bit(STRIPE_INSYNC, &sh->state)) {
c5a31000
N		 4915 md_done_sync(conf->mddev, STRIPE_SECTORS, 1);
4916 clear_bit(STRIPE_SYNCING, &sh->state);
f8dfcffd
N		 4917 if (test_and_clear_bit(R5_Overlap, &sh->dev[sh->pd_idx].flags))
4918 wake_up(&conf->wait_for_overlap);
c5a31000
N		 4919 }
4920
4921 /* If the failed drives are just a ReadError, then we might need
4922 * to progress the repair/check process
4923 */
4924 if (s.failed <= conf->max_degraded && !conf->mddev->ro)
4925 for (i = 0; i < s.failed; i++) {
4926 struct r5dev *dev = &sh->dev[s.failed_num[i]];
4927 if (test_bit(R5_ReadError, &dev->flags)
4928 && !test_bit(R5_LOCKED, &dev->flags)
4929 && test_bit(R5_UPTODATE, &dev->flags)
4930 ) {
4931 if (!test_bit(R5_ReWrite, &dev->flags)) {
4932 set_bit(R5_Wantwrite, &dev->flags);
4933 set_bit(R5_ReWrite, &dev->flags);
4934 set_bit(R5_LOCKED, &dev->flags);
4935 s.locked++;
4936 } else {
4937 /* let's read it back */
4938 set_bit(R5_Wantread, &dev->flags);
4939 set_bit(R5_LOCKED, &dev->flags);
4940 s.locked++;
4941 }
4942 }
4943 }
4944
3687c061
N		 4945 /* Finish reconstruct operations initiated by the expansion process */
4946 if (sh->reconstruct_state == reconstruct_state_result) {
4947 struct stripe_head *sh_src
6d036f7d 4948 = raid5_get_active_stripe(conf, sh->sector, 1, 1, 1);
3687c061
N		 4949 if (sh_src && test_bit(STRIPE_EXPAND_SOURCE, &sh_src->state)) {
4950 /* sh cannot be written until sh_src has been read.
4951 * so arrange for sh to be delayed a little
4952 */
4953 set_bit(STRIPE_DELAYED, &sh->state);
4954 set_bit(STRIPE_HANDLE, &sh->state);
4955 if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE,
4956 &sh_src->state))
4957 atomic_inc(&conf->preread_active_stripes);
6d036f7d 4958 raid5_release_stripe(sh_src);
3687c061
N		 4959 goto finish;
4960 }
4961 if (sh_src)
6d036f7d 4962 raid5_release_stripe(sh_src);
3687c061
N		 4963
4964 sh->reconstruct_state = reconstruct_state_idle;
4965 clear_bit(STRIPE_EXPANDING, &sh->state);
4966 for (i = conf->raid_disks; i--; ) {
4967 set_bit(R5_Wantwrite, &sh->dev[i].flags);
4968 set_bit(R5_LOCKED, &sh->dev[i].flags);
4969 s.locked++;
4970 }
4971 }
f416885e 4972
3687c061
N		 4973 if (s.expanded && test_bit(STRIPE_EXPANDING, &sh->state) &&
4974 !sh->reconstruct_state) {
4975 /* Need to write out all blocks after computing parity */
4976 sh->disks = conf->raid_disks;
4977 stripe_set_idx(sh->sector, conf, 0, sh);
4978 schedule_reconstruction(sh, &s, 1, 1);
4979 } else if (s.expanded && !sh->reconstruct_state && s.locked == 0) {
4980 clear_bit(STRIPE_EXPAND_READY, &sh->state);
4981 atomic_dec(&conf->reshape_stripes);
4982 wake_up(&conf->wait_for_overlap);
4983 md_done_sync(conf->mddev, STRIPE_SECTORS, 1);
4984 }
4985
4986 if (s.expanding && s.locked == 0 &&
4987 !test_bit(STRIPE_COMPUTE_RUN, &sh->state))
4988 handle_stripe_expansion(conf, sh);
16a53ecc 4989
3687c061 4990finish:
6bfe0b49 4991 /* wait for this device to become unblocked */
5f066c63
N		 4992 if (unlikely(s.blocked_rdev)) {
4993 if (conf->mddev->external)
4994 md_wait_for_blocked_rdev(s.blocked_rdev,
4995 conf->mddev);
4996 else
4997 /* Internal metadata will immediately
4998 * be written by raid5d, so we don't
4999 * need to wait here.
5000 */
5001 rdev_dec_pending(s.blocked_rdev,
5002 conf->mddev);
5003 }
6bfe0b49 5004
bc2607f3
N		 5005 if (s.handle_bad_blocks)
5006 for (i = disks; i--; ) {
3cb03002 5007 struct md_rdev *rdev;
bc2607f3
N		 5008 struct r5dev *dev = &sh->dev[i];
5009 if (test_and_clear_bit(R5_WriteError, &dev->flags)) {
5010 /* We own a safe reference to the rdev */
5011 rdev = conf->disks[i].rdev;
5012 if (!rdev_set_badblocks(rdev, sh->sector,
5013 STRIPE_SECTORS, 0))
5014 md_error(conf->mddev, rdev);
5015 rdev_dec_pending(rdev, conf->mddev);
5016 }
b84db560
N		 5017 if (test_and_clear_bit(R5_MadeGood, &dev->flags)) {
5018 rdev = conf->disks[i].rdev;
5019 rdev_clear_badblocks(rdev, sh->sector,
c6563a8c 5020 STRIPE_SECTORS, 0);
b84db560
N		 5021 rdev_dec_pending(rdev, conf->mddev);
5022 }
977df362
N		 5023 if (test_and_clear_bit(R5_MadeGoodRepl, &dev->flags)) {
5024 rdev = conf->disks[i].replacement;
dd054fce
N		 5025 if (!rdev)
5026 /* rdev have been moved down */
5027 rdev = conf->disks[i].rdev;
977df362 5028 rdev_clear_badblocks(rdev, sh->sector,
c6563a8c 5029 STRIPE_SECTORS, 0);
977df362
N		 5030 rdev_dec_pending(rdev, conf->mddev);
5031 }
bc2607f3
N		 5032 }
5033
6c0069c0
YT		 5034 if (s.ops_request)
5035 raid_run_ops(sh, s.ops_request);
5036
f0e43bcd 5037 ops_run_io(sh, &s);
16a53ecc 5038
c5709ef6 5039 if (s.dec_preread_active) {
729a1866 5040 /* We delay this until after ops_run_io so that if make_request
e9c7469b 5041 * is waiting on a flush, it won't continue until the writes
729a1866
N		 5042 * have actually been submitted.
5043 */
5044 atomic_dec(&conf->preread_active_stripes);
5045 if (atomic_read(&conf->preread_active_stripes) <
5046 IO_THRESHOLD)
5047 md_wakeup_thread(conf->mddev->thread);
5048 }
5049
257a4b42 5050 clear_bit_unlock(STRIPE_ACTIVE, &sh->state);
16a53ecc
N		 5051}
5052
d1688a6d 5053static void raid5_activate_delayed(struct r5conf *conf)
16a53ecc
N		 5054{
5055 if (atomic_read(&conf->preread_active_stripes) < IO_THRESHOLD) {
5056 while (!list_empty(&conf->delayed_list)) {
5057 struct list_head *l = conf->delayed_list.next;
5058 struct stripe_head *sh;
5059 sh = list_entry(l, struct stripe_head, lru);
5060 list_del_init(l);
5061 clear_bit(STRIPE_DELAYED, &sh->state);
5062 if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE, &sh->state))
5063 atomic_inc(&conf->preread_active_stripes);
8b3e6cdc 5064 list_add_tail(&sh->lru, &conf->hold_list);
851c30c9 5065 raid5_wakeup_stripe_thread(sh);
16a53ecc 5066 }
482c0834 5067 }
16a53ecc
N		 5068}
5069
566c09c5
SL		 5070static void activate_bit_delay(struct r5conf *conf,
5071 struct list_head *temp_inactive_list)
16a53ecc
N		 5072{
5073 /* device_lock is held */
5074 struct list_head head;
5075 list_add(&head, &conf->bitmap_list);
5076 list_del_init(&conf->bitmap_list);
5077 while (!list_empty(&head)) {
5078 struct stripe_head *sh = list_entry(head.next, struct stripe_head, lru);
566c09c5 5079 int hash;
16a53ecc
N		 5080 list_del_init(&sh->lru);
5081 atomic_inc(&sh->count);
566c09c5
SL		 5082 hash = sh->hash_lock_index;
5083 __release_stripe(conf, sh, &temp_inactive_list[hash]);
16a53ecc
N		 5084 }
5085}
5086
5c675f83 5087static int raid5_congested(struct mddev *mddev, int bits)
f022b2fd 5088{
d1688a6d 5089 struct r5conf *conf = mddev->private;
f022b2fd
N		 5090
5091 /* No difference between reads and writes. Just check
5092 * how busy the stripe_cache is
5093 */
3fa841d7 5094
5423399a 5095 if (test_bit(R5_INACTIVE_BLOCKED, &conf->cache_state))
f022b2fd 5096 return 1;
a39f7afd
SL		 5097
5098 /* Also checks whether there is pressure on r5cache log space */
5099 if (test_bit(R5C_LOG_TIGHT, &conf->cache_state))
5100 return 1;
f022b2fd
N		 5101 if (conf->quiesce)
5102 return 1;
4bda556a 5103 if (atomic_read(&conf->empty_inactive_list_nr))
f022b2fd
N		 5104 return 1;
5105
5106 return 0;
5107}
5108
fd01b88c 5109static int in_chunk_boundary(struct mddev *mddev, struct bio *bio)
f679623f 5110{
3cb5edf4 5111 struct r5conf *conf = mddev->private;
10433d04 5112 sector_t sector = bio->bi_iter.bi_sector;
3cb5edf4 5113 unsigned int chunk_sectors;
aa8b57aa 5114 unsigned int bio_sectors = bio_sectors(bio);
f679623f 5115
10433d04
CH		 5116 WARN_ON_ONCE(bio->bi_partno);
5117
3cb5edf4 5118 chunk_sectors = min(conf->chunk_sectors, conf->prev_chunk_sectors);
f679623f
RBJ		 5119 return chunk_sectors >=
5120 ((sector & (chunk_sectors - 1)) + bio_sectors);
5121}
5122
46031f9a
RBJ		 5123/*
5124 * add bio to the retry LIFO ( in O(1) ... we are in interrupt )
5125 * later sampled by raid5d.
5126 */
d1688a6d 5127static void add_bio_to_retry(struct bio *bi,struct r5conf *conf)
46031f9a
RBJ		 5128{
5129 unsigned long flags;
5130
5131 spin_lock_irqsave(&conf->device_lock, flags);
5132
5133 bi->bi_next = conf->retry_read_aligned_list;
5134 conf->retry_read_aligned_list = bi;
5135
5136 spin_unlock_irqrestore(&conf->device_lock, flags);
5137 md_wakeup_thread(conf->mddev->thread);
5138}
5139
0472a42b
N		 5140static struct bio *remove_bio_from_retry(struct r5conf *conf,
5141 unsigned int *offset)
46031f9a
RBJ		 5142{
5143 struct bio *bi;
5144
5145 bi = conf->retry_read_aligned;
5146 if (bi) {
0472a42b 5147 *offset = conf->retry_read_offset;
46031f9a
RBJ		 5148 conf->retry_read_aligned = NULL;
5149 return bi;
5150 }
5151 bi = conf->retry_read_aligned_list;
5152 if(bi) {
387bb173 5153 conf->retry_read_aligned_list = bi->bi_next;
46031f9a 5154 bi->bi_next = NULL;
0472a42b 5155 *offset = 0;
46031f9a
RBJ		 5156 }
5157
5158 return bi;
5159}
5160
f679623f
RBJ		 5161/*
5162 * The "raid5_align_endio" should check if the read succeeded and if it
5163 * did, call bio_endio on the original bio (having bio_put the new bio
5164 * first).
5165 * If the read failed..
5166 */
4246a0b6 5167static void raid5_align_endio(struct bio *bi)
f679623f
RBJ		 5168{
5169 struct bio* raid_bi = bi->bi_private;
fd01b88c 5170 struct mddev *mddev;
d1688a6d 5171 struct r5conf *conf;
3cb03002 5172 struct md_rdev *rdev;
4e4cbee9 5173 blk_status_t error = bi->bi_status;
46031f9a 5174
f679623f 5175 bio_put(bi);
46031f9a 5176
46031f9a
RBJ		 5177 rdev = (void*)raid_bi->bi_next;
5178 raid_bi->bi_next = NULL;
2b7f2228
N		 5179 mddev = rdev->mddev;
5180 conf = mddev->private;
46031f9a
RBJ		 5181
5182 rdev_dec_pending(rdev, conf->mddev);
5183
9b81c842 5184 if (!error) {
4246a0b6 5185 bio_endio(raid_bi);
46031f9a 5186 if (atomic_dec_and_test(&conf->active_aligned_reads))
b1b46486 5187 wake_up(&conf->wait_for_quiescent);
6712ecf8 5188 return;
46031f9a
RBJ		 5189 }
5190
45b4233c 5191 pr_debug("raid5_align_endio : io error...handing IO for a retry\n");
46031f9a
RBJ		 5192
5193 add_bio_to_retry(raid_bi, conf);
f679623f
RBJ		 5194}
5195
7ef6b12a 5196static int raid5_read_one_chunk(struct mddev *mddev, struct bio *raid_bio)
f679623f 5197{
d1688a6d 5198 struct r5conf *conf = mddev->private;
8553fe7e 5199 int dd_idx;
f679623f 5200 struct bio* align_bi;
3cb03002 5201 struct md_rdev *rdev;
671488cc 5202 sector_t end_sector;
f679623f
RBJ		 5203
5204 if (!in_chunk_boundary(mddev, raid_bio)) {
7ef6b12a 5205 pr_debug("%s: non aligned\n", __func__);
f679623f
RBJ		 5206 return 0;
5207 }
5208 /*
d7a10308 5209 * use bio_clone_fast to make a copy of the bio
f679623f 5210 */
afeee514 5211 align_bi = bio_clone_fast(raid_bio, GFP_NOIO, &mddev->bio_set);
f679623f
RBJ		 5212 if (!align_bi)
5213 return 0;
5214 /*
5215 * set bi_end_io to a new function, and set bi_private to the
5216 * original bio.
5217 */
5218 align_bi->bi_end_io = raid5_align_endio;
5219 align_bi->bi_private = raid_bio;
5220 /*
5221 * compute position
5222 */
4f024f37
KO		 5223 align_bi->bi_iter.bi_sector =
5224 raid5_compute_sector(conf, raid_bio->bi_iter.bi_sector,
5225 0, &dd_idx, NULL);
f679623f 5226
f73a1c7d 5227 end_sector = bio_end_sector(align_bi);
f679623f 5228 rcu_read_lock();
671488cc
N		 5229 rdev = rcu_dereference(conf->disks[dd_idx].replacement);
5230 if (!rdev || test_bit(Faulty, &rdev->flags) ||
5231 rdev->recovery_offset < end_sector) {
5232 rdev = rcu_dereference(conf->disks[dd_idx].rdev);
5233 if (rdev &&
5234 (test_bit(Faulty, &rdev->flags) ||
5235 !(test_bit(In_sync, &rdev->flags) ||
5236 rdev->recovery_offset >= end_sector)))
5237 rdev = NULL;
5238 }
03b047f4
SL		 5239
5240 if (r5c_big_stripe_cached(conf, align_bi->bi_iter.bi_sector)) {
5241 rcu_read_unlock();
5242 bio_put(align_bi);
5243 return 0;
5244 }
5245
671488cc 5246 if (rdev) {
31c176ec
N		 5247 sector_t first_bad;
5248 int bad_sectors;
5249
f679623f
RBJ		 5250 atomic_inc(&rdev->nr_pending);
5251 rcu_read_unlock();
46031f9a 5252 raid_bio->bi_next = (void*)rdev;
74d46992 5253 bio_set_dev(align_bi, rdev->bdev);
46031f9a 5254
7140aafc 5255 if (is_badblock(rdev, align_bi->bi_iter.bi_sector,
4f024f37 5256 bio_sectors(align_bi),
31c176ec 5257 &first_bad, &bad_sectors)) {
387bb173
NB		 5258 bio_put(align_bi);
5259 rdev_dec_pending(rdev, mddev);
5260 return 0;
5261 }
5262
6c0544e2 5263 /* No reshape active, so we can trust rdev->data_offset */
4f024f37 5264 align_bi->bi_iter.bi_sector += rdev->data_offset;
6c0544e2 5265
46031f9a 5266 spin_lock_irq(&conf->device_lock);
b1b46486 5267 wait_event_lock_irq(conf->wait_for_quiescent,
46031f9a 5268 conf->quiesce == 0,
eed8c02e 5269 conf->device_lock);
46031f9a
RBJ		 5270 atomic_inc(&conf->active_aligned_reads);
5271 spin_unlock_irq(&conf->device_lock);
5272
e3620a3a 5273 if (mddev->gendisk)
74d46992 5274 trace_block_bio_remap(align_bi->bi_disk->queue,
e3620a3a 5275 align_bi, disk_devt(mddev->gendisk),
4f024f37 5276 raid_bio->bi_iter.bi_sector);
f679623f
RBJ		 5277 generic_make_request(align_bi);
5278 return 1;
5279 } else {
5280 rcu_read_unlock();
46031f9a 5281 bio_put(align_bi);
f679623f
RBJ		 5282 return 0;
5283 }
5284}
5285
7ef6b12a
ML		 5286static struct bio *chunk_aligned_read(struct mddev *mddev, struct bio *raid_bio)
5287{
5288 struct bio *split;
dd7a8f5d
N		 5289 sector_t sector = raid_bio->bi_iter.bi_sector;
5290 unsigned chunk_sects = mddev->chunk_sectors;
5291 unsigned sectors = chunk_sects - (sector & (chunk_sects-1));
7ef6b12a 5292
dd7a8f5d
N		 5293 if (sectors < bio_sectors(raid_bio)) {
5294 struct r5conf *conf = mddev->private;
afeee514 5295 split = bio_split(raid_bio, sectors, GFP_NOIO, &conf->bio_split);
dd7a8f5d
N		 5296 bio_chain(split, raid_bio);
5297 generic_make_request(raid_bio);
5298 raid_bio = split;
5299 }
7ef6b12a 5300
dd7a8f5d
N		 5301 if (!raid5_read_one_chunk(mddev, raid_bio))
5302 return raid_bio;
7ef6b12a
ML		 5303
5304 return NULL;
5305}
5306
8b3e6cdc
DW		 5307/* __get_priority_stripe - get the next stripe to process
5308 *
5309 * Full stripe writes are allowed to pass preread active stripes up until
5310 * the bypass_threshold is exceeded. In general the bypass_count
5311 * increments when the handle_list is handled before the hold_list; however, it
5312 * will not be incremented when STRIPE_IO_STARTED is sampled set signifying a
5313 * stripe with in flight i/o. The bypass_count will be reset when the
5314 * head of the hold_list has changed, i.e. the head was promoted to the
5315 * handle_list.
5316 */
851c30c9 5317static struct stripe_head *__get_priority_stripe(struct r5conf *conf, int group)
8b3e6cdc 5318{
535ae4eb 5319 struct stripe_head *sh, *tmp;
851c30c9 5320 struct list_head *handle_list = NULL;
535ae4eb 5321 struct r5worker_group *wg;
70d466f7
SL		 5322 bool second_try = !r5c_is_writeback(conf->log) &&
5323 !r5l_log_disk_error(conf);
5324 bool try_loprio = test_bit(R5C_LOG_TIGHT, &conf->cache_state) ||
5325 r5l_log_disk_error(conf);
851c30c9 5326
535ae4eb
SL		 5327again:
5328 wg = NULL;
5329 sh = NULL;
851c30c9 5330 if (conf->worker_cnt_per_group == 0) {
535ae4eb
SL		 5331 handle_list = try_loprio ? &conf->loprio_list :
5332 &conf->handle_list;
851c30c9 5333 } else if (group != ANY_GROUP) {
535ae4eb
SL		 5334 handle_list = try_loprio ? &conf->worker_groups[group].loprio_list :
5335 &conf->worker_groups[group].handle_list;
bfc90cb0 5336 wg = &conf->worker_groups[group];
851c30c9
SL		 5337 } else {
5338 int i;
5339 for (i = 0; i < conf->group_cnt; i++) {
535ae4eb
SL		 5340 handle_list = try_loprio ? &conf->worker_groups[i].loprio_list :
5341 &conf->worker_groups[i].handle_list;
bfc90cb0 5342 wg = &conf->worker_groups[i];
851c30c9
SL		 5343 if (!list_empty(handle_list))
5344 break;
5345 }
5346 }
8b3e6cdc
DW		 5347
5348 pr_debug("%s: handle: %s hold: %s full_writes: %d bypass_count: %d\n",
5349 __func__,
851c30c9 5350 list_empty(handle_list) ? "empty" : "busy",
8b3e6cdc
DW		 5351 list_empty(&conf->hold_list) ? "empty" : "busy",
5352 atomic_read(&conf->pending_full_writes), conf->bypass_count);
5353
851c30c9
SL		 5354 if (!list_empty(handle_list)) {
5355 sh = list_entry(handle_list->next, typeof(*sh), lru);
8b3e6cdc
DW		 5356
5357 if (list_empty(&conf->hold_list))
5358 conf->bypass_count = 0;
5359 else if (!test_bit(STRIPE_IO_STARTED, &sh->state)) {
5360 if (conf->hold_list.next == conf->last_hold)
5361 conf->bypass_count++;
5362 else {
5363 conf->last_hold = conf->hold_list.next;
5364 conf->bypass_count -= conf->bypass_threshold;
5365 if (conf->bypass_count < 0)
5366 conf->bypass_count = 0;
5367 }
5368 }
5369 } else if (!list_empty(&conf->hold_list) &&
5370 ((conf->bypass_threshold &&
5371 conf->bypass_count > conf->bypass_threshold) ||
5372 atomic_read(&conf->pending_full_writes) == 0)) {
851c30c9
SL		 5373
5374 list_for_each_entry(tmp, &conf->hold_list, lru) {
5375 if (conf->worker_cnt_per_group == 0 ||
5376 group == ANY_GROUP ||
5377 !cpu_online(tmp->cpu) ||
5378 cpu_to_group(tmp->cpu) == group) {
5379 sh = tmp;
5380 break;
5381 }
5382 }
5383
5384 if (sh) {
5385 conf->bypass_count -= conf->bypass_threshold;
5386 if (conf->bypass_count < 0)
5387 conf->bypass_count = 0;
5388 }
bfc90cb0 5389 wg = NULL;
851c30c9
SL		 5390 }
5391
535ae4eb
SL		 5392 if (!sh) {
5393 if (second_try)
5394 return NULL;
5395 second_try = true;
5396 try_loprio = !try_loprio;
5397 goto again;
5398 }
8b3e6cdc 5399
bfc90cb0
SL		 5400 if (wg) {
5401 wg->stripes_cnt--;
5402 sh->group = NULL;
5403 }
8b3e6cdc 5404 list_del_init(&sh->lru);
c7a6d35e 5405 BUG_ON(atomic_inc_return(&sh->count) != 1);
8b3e6cdc
DW		 5406 return sh;
5407}
f679623f 5408
8811b596
SL		 5409struct raid5_plug_cb {
5410 struct blk_plug_cb cb;
5411 struct list_head list;
566c09c5 5412 struct list_head temp_inactive_list[NR_STRIPE_HASH_LOCKS];
8811b596
SL		 5413};
5414
5415static void raid5_unplug(struct blk_plug_cb *blk_cb, bool from_schedule)
5416{
5417 struct raid5_plug_cb *cb = container_of(
5418 blk_cb, struct raid5_plug_cb, cb);
5419 struct stripe_head *sh;
5420 struct mddev *mddev = cb->cb.data;
5421 struct r5conf *conf = mddev->private;
a9add5d9 5422 int cnt = 0;
566c09c5 5423 int hash;
8811b596
SL		 5424
5425 if (cb->list.next && !list_empty(&cb->list)) {
5426 spin_lock_irq(&conf->device_lock);
5427 while (!list_empty(&cb->list)) {
5428 sh = list_first_entry(&cb->list, struct stripe_head, lru);
5429 list_del_init(&sh->lru);
5430 /*
5431 * avoid race release_stripe_plug() sees
5432 * STRIPE_ON_UNPLUG_LIST clear but the stripe
5433 * is still in our list
5434 */
4e857c58 5435 smp_mb__before_atomic();
8811b596 5436 clear_bit(STRIPE_ON_UNPLUG_LIST, &sh->state);
773ca82f
SL		 5437 /*
5438 * STRIPE_ON_RELEASE_LIST could be set here. In that
5439 * case, the count is always > 1 here
5440 */
566c09c5
SL		 5441 hash = sh->hash_lock_index;
5442 __release_stripe(conf, sh, &cb->temp_inactive_list[hash]);
a9add5d9 5443 cnt++;
8811b596
SL		 5444 }
5445 spin_unlock_irq(&conf->device_lock);
5446 }
566c09c5
SL		 5447 release_inactive_stripe_list(conf, cb->temp_inactive_list,
5448 NR_STRIPE_HASH_LOCKS);
e3620a3a
JB		 5449 if (mddev->queue)
5450 trace_block_unplug(mddev->queue, cnt, !from_schedule);
8811b596
SL		 5451 kfree(cb);
5452}
5453
5454static void release_stripe_plug(struct mddev *mddev,
5455 struct stripe_head *sh)
5456{
5457 struct blk_plug_cb *blk_cb = blk_check_plugged(
5458 raid5_unplug, mddev,
5459 sizeof(struct raid5_plug_cb));
5460 struct raid5_plug_cb *cb;
5461
5462 if (!blk_cb) {
6d036f7d 5463 raid5_release_stripe(sh);
8811b596
SL		 5464 return;
5465 }
5466
5467 cb = container_of(blk_cb, struct raid5_plug_cb, cb);
5468
566c09c5
SL		 5469 if (cb->list.next == NULL) {
5470 int i;
8811b596 5471 INIT_LIST_HEAD(&cb->list);
566c09c5
SL		 5472 for (i = 0; i < NR_STRIPE_HASH_LOCKS; i++)
5473 INIT_LIST_HEAD(cb->temp_inactive_list + i);
5474 }
8811b596
SL		 5475
5476 if (!test_and_set_bit(STRIPE_ON_UNPLUG_LIST, &sh->state))
5477 list_add_tail(&sh->lru, &cb->list);
5478 else
6d036f7d 5479 raid5_release_stripe(sh);
8811b596
SL		 5480}
5481
620125f2
SL		 5482static void make_discard_request(struct mddev *mddev, struct bio *bi)
5483{
5484 struct r5conf *conf = mddev->private;
5485 sector_t logical_sector, last_sector;
5486 struct stripe_head *sh;
620125f2
SL		 5487 int stripe_sectors;
5488
5489 if (mddev->reshape_position != MaxSector)
5490 /* Skip discard while reshape is happening */
5491 return;
5492
4f024f37
KO		 5493 logical_sector = bi->bi_iter.bi_sector & ~((sector_t)STRIPE_SECTORS-1);
5494 last_sector = bi->bi_iter.bi_sector + (bi->bi_iter.bi_size>>9);
620125f2
SL		 5495
5496 bi->bi_next = NULL;
620125f2
SL		 5497
5498 stripe_sectors = conf->chunk_sectors *
5499 (conf->raid_disks - conf->max_degraded);
5500 logical_sector = DIV_ROUND_UP_SECTOR_T(logical_sector,
5501 stripe_sectors);
5502 sector_div(last_sector, stripe_sectors);
5503
5504 logical_sector *= conf->chunk_sectors;
5505 last_sector *= conf->chunk_sectors;
5506
5507 for (; logical_sector < last_sector;
5508 logical_sector += STRIPE_SECTORS) {
5509 DEFINE_WAIT(w);
5510 int d;
5511 again:
6d036f7d 5512 sh = raid5_get_active_stripe(conf, logical_sector, 0, 0, 0);
620125f2
SL		 5513 prepare_to_wait(&conf->wait_for_overlap, &w,
5514 TASK_UNINTERRUPTIBLE);
f8dfcffd
N		 5515 set_bit(R5_Overlap, &sh->dev[sh->pd_idx].flags);
5516 if (test_bit(STRIPE_SYNCING, &sh->state)) {
6d036f7d 5517 raid5_release_stripe(sh);
f8dfcffd
N		 5518 schedule();
5519 goto again;
5520 }
5521 clear_bit(R5_Overlap, &sh->dev[sh->pd_idx].flags);
620125f2
SL		 5522 spin_lock_irq(&sh->stripe_lock);
5523 for (d = 0; d < conf->raid_disks; d++) {
5524 if (d == sh->pd_idx || d == sh->qd_idx)
5525 continue;
5526 if (sh->dev[d].towrite || sh->dev[d].toread) {
5527 set_bit(R5_Overlap, &sh->dev[d].flags);
5528 spin_unlock_irq(&sh->stripe_lock);
6d036f7d 5529 raid5_release_stripe(sh);
620125f2
SL		 5530 schedule();
5531 goto again;
5532 }
5533 }
f8dfcffd 5534 set_bit(STRIPE_DISCARD, &sh->state);
620125f2 5535 finish_wait(&conf->wait_for_overlap, &w);
7a87f434 5536 sh->overwrite_disks = 0;
620125f2
SL		 5537 for (d = 0; d < conf->raid_disks; d++) {
5538 if (d == sh->pd_idx || d == sh->qd_idx)
5539 continue;
5540 sh->dev[d].towrite = bi;
5541 set_bit(R5_OVERWRITE, &sh->dev[d].flags);
016c76ac 5542 bio_inc_remaining(bi);
49728050 5543 md_write_inc(mddev, bi);
7a87f434 5544 sh->overwrite_disks++;
620125f2
SL		 5545 }
5546 spin_unlock_irq(&sh->stripe_lock);
5547 if (conf->mddev->bitmap) {
5548 for (d = 0;
5549 d < conf->raid_disks - conf->max_degraded;
5550 d++)
e64e4018
AS		 5551 md_bitmap_startwrite(mddev->bitmap,
5552 sh->sector,
5553 STRIPE_SECTORS,
5554 0);
620125f2
SL		 5555 sh->bm_seq = conf->seq_flush + 1;
5556 set_bit(STRIPE_BIT_DELAY, &sh->state);
5557 }
5558
5559 set_bit(STRIPE_HANDLE, &sh->state);
5560 clear_bit(STRIPE_DELAYED, &sh->state);
5561 if (!test_and_set_bit(STRIPE_PREREAD_ACTIVE, &sh->state))
5562 atomic_inc(&conf->preread_active_stripes);
5563 release_stripe_plug(mddev, sh);
5564 }
5565
016c76ac 5566 bio_endio(bi);
620125f2
SL		 5567}
5568
cc27b0c7 5569static bool raid5_make_request(struct mddev *mddev, struct bio * bi)
1da177e4 5570{
d1688a6d 5571 struct r5conf *conf = mddev->private;
911d4ee8 5572 int dd_idx;
1da177e4
LT		 5573 sector_t new_sector;
5574 sector_t logical_sector, last_sector;
5575 struct stripe_head *sh;
a362357b 5576 const int rw = bio_data_dir(bi);
27c0f68f
SL		 5577 DEFINE_WAIT(w);
5578 bool do_prepare;
3bddb7f8 5579 bool do_flush = false;
1da177e4 5580
1eff9d32 5581 if (unlikely(bi->bi_opf & REQ_PREFLUSH)) {
1532d9e8 5582 int ret = log_handle_flush_request(conf, bi);
828cbe98
SL		 5583
5584 if (ret == 0)
cc27b0c7 5585 return true;
828cbe98
SL		 5586 if (ret == -ENODEV) {
5587 md_flush_request(mddev, bi);
cc27b0c7 5588 return true;
828cbe98
SL		 5589 }
5590 /* ret == -EAGAIN, fallback */
3bddb7f8
SL		 5591 /*
5592 * if r5l_handle_flush_request() didn't clear REQ_PREFLUSH,
5593 * we need to flush journal device
5594 */
5595 do_flush = bi->bi_opf & REQ_PREFLUSH;
e5dcdd80
N		 5596 }
5597
cc27b0c7
N		 5598 if (!md_write_start(mddev, bi))
5599 return false;
9ffc8f7c
EM		 5600 /*
5601 * If array is degraded, better not do chunk aligned read because
5602 * later we might have to read it again in order to reconstruct
5603 * data on failed drives.
5604 */
5605 if (rw == READ && mddev->degraded == 0 &&
7ef6b12a
ML		 5606 mddev->reshape_position == MaxSector) {
5607 bi = chunk_aligned_read(mddev, bi);
5608 if (!bi)
cc27b0c7 5609 return true;
7ef6b12a 5610 }
52488615 5611
796a5cf0 5612 if (unlikely(bio_op(bi) == REQ_OP_DISCARD)) {
620125f2 5613 make_discard_request(mddev, bi);
cc27b0c7
N		 5614 md_write_end(mddev);
5615 return true;
620125f2
SL		 5616 }
5617
4f024f37 5618 logical_sector = bi->bi_iter.bi_sector & ~((sector_t)STRIPE_SECTORS-1);
f73a1c7d 5619 last_sector = bio_end_sector(bi);
1da177e4 5620 bi->bi_next = NULL;
06d91a5f 5621
27c0f68f 5622 prepare_to_wait(&conf->wait_for_overlap, &w, TASK_UNINTERRUPTIBLE);
1da177e4 5623 for (;logical_sector < last_sector; logical_sector += STRIPE_SECTORS) {
b5663ba4 5624 int previous;
c46501b2 5625 int seq;
b578d55f 5626
27c0f68f 5627 do_prepare = false;
7ecaa1e6 5628 retry:
c46501b2 5629 seq = read_seqcount_begin(&conf->gen_lock);
b5663ba4 5630 previous = 0;
27c0f68f
SL		 5631 if (do_prepare)
5632 prepare_to_wait(&conf->wait_for_overlap, &w,
5633 TASK_UNINTERRUPTIBLE);
b0f9ec04 5634 if (unlikely(conf->reshape_progress != MaxSector)) {
fef9c61f 5635 /* spinlock is needed as reshape_progress may be
df8e7f76
N		 5636 * 64bit on a 32bit platform, and so it might be
5637 * possible to see a half-updated value
aeb878b0 5638 * Of course reshape_progress could change after
df8e7f76
N		 5639 * the lock is dropped, so once we get a reference
5640 * to the stripe that we think it is, we will have
5641 * to check again.
5642 */
7ecaa1e6 5643 spin_lock_irq(&conf->device_lock);
2c810cdd 5644 if (mddev->reshape_backwards
fef9c61f
N		 5645 ? logical_sector < conf->reshape_progress
5646 : logical_sector >= conf->reshape_progress) {
b5663ba4
N		 5647 previous = 1;
5648 } else {
2c810cdd 5649 if (mddev->reshape_backwards
fef9c61f
N		 5650 ? logical_sector < conf->reshape_safe
5651 : logical_sector >= conf->reshape_safe) {
b578d55f
N		 5652 spin_unlock_irq(&conf->device_lock);
5653 schedule();
27c0f68f 5654 do_prepare = true;
b578d55f
N		 5655 goto retry;
5656 }
5657 }
7ecaa1e6
N		 5658 spin_unlock_irq(&conf->device_lock);
5659 }
16a53ecc 5660
112bf897
N		 5661 new_sector = raid5_compute_sector(conf, logical_sector,
5662 previous,
911d4ee8 5663 &dd_idx, NULL);
849674e4 5664 pr_debug("raid456: raid5_make_request, sector %llu logical %llu\n",
c46501b2 5665 (unsigned long long)new_sector,
1da177e4
LT		 5666 (unsigned long long)logical_sector);
5667
6d036f7d 5668 sh = raid5_get_active_stripe(conf, new_sector, previous,
1eff9d32 5669 (bi->bi_opf & REQ_RAHEAD), 0);
1da177e4 5670 if (sh) {
b0f9ec04 5671 if (unlikely(previous)) {
7ecaa1e6 5672 /* expansion might have moved on while waiting for a
df8e7f76
N		 5673 * stripe, so we must do the range check again.
5674 * Expansion could still move past after this
5675 * test, but as we are holding a reference to
5676 * 'sh', we know that if that happens,
5677 * STRIPE_EXPANDING will get set and the expansion
5678 * won't proceed until we finish with the stripe.
7ecaa1e6
N		 5679 */
5680 int must_retry = 0;
5681 spin_lock_irq(&conf->device_lock);
2c810cdd 5682 if (mddev->reshape_backwards
b0f9ec04
N		 5683 ? logical_sector >= conf->reshape_progress
5684 : logical_sector < conf->reshape_progress)
7ecaa1e6
N		 5685 /* mismatch, need to try again */
5686 must_retry = 1;
5687 spin_unlock_irq(&conf->device_lock);
5688 if (must_retry) {
6d036f7d 5689 raid5_release_stripe(sh);
7a3ab908 5690 schedule();
27c0f68f 5691 do_prepare = true;
7ecaa1e6
N		 5692 goto retry;
5693 }
5694 }
c46501b2
N		 5695 if (read_seqcount_retry(&conf->gen_lock, seq)) {
5696 /* Might have got the wrong stripe_head
5697 * by accident
5698 */
6d036f7d 5699 raid5_release_stripe(sh);
c46501b2
N		 5700 goto retry;
5701 }
e62e58a5 5702
7ecaa1e6 5703 if (test_bit(STRIPE_EXPANDING, &sh->state) ||
da41ba65 5704 !add_stripe_bio(sh, bi, dd_idx, rw, previous)) {
7ecaa1e6
N		 5705 /* Stripe is busy expanding or
5706 * add failed due to overlap. Flush everything
1da177e4
LT		 5707 * and wait a while
5708 */
482c0834 5709 md_wakeup_thread(mddev->thread);
6d036f7d 5710 raid5_release_stripe(sh);
1da177e4 5711 schedule();
27c0f68f 5712 do_prepare = true;
1da177e4
LT		 5713 goto retry;
5714 }
3bddb7f8
SL		 5715 if (do_flush) {
5716 set_bit(STRIPE_R5C_PREFLUSH, &sh->state);
5717 /* we only need flush for one stripe */
5718 do_flush = false;
5719 }
5720
6ed3003c
N		 5721 set_bit(STRIPE_HANDLE, &sh->state);
5722 clear_bit(STRIPE_DELAYED, &sh->state);
59fc630b 5723 if ((!sh->batch_head || sh == sh->batch_head) &&
1eff9d32 5724 (bi->bi_opf & REQ_SYNC) &&
729a1866
N		 5725 !test_and_set_bit(STRIPE_PREREAD_ACTIVE, &sh->state))
5726 atomic_inc(&conf->preread_active_stripes);
8811b596 5727 release_stripe_plug(mddev, sh);
1da177e4
LT		 5728 } else {
5729 /* cannot get stripe for read-ahead, just give-up */
4e4cbee9 5730 bi->bi_status = BLK_STS_IOERR;
1da177e4
LT		 5731 break;
5732 }
1da177e4 5733 }
27c0f68f 5734 finish_wait(&conf->wait_for_overlap, &w);
7c13edc8 5735
49728050
N		 5736 if (rw == WRITE)
5737 md_write_end(mddev);
016c76ac 5738 bio_endio(bi);
cc27b0c7 5739 return true;
1da177e4
LT		 5740}
5741
fd01b88c 5742static sector_t raid5_size(struct mddev *mddev, sector_t sectors, int raid_disks);
b522adcd 5743
fd01b88c 5744static sector_t reshape_request(struct mddev *mddev, sector_t sector_nr, int *skipped)
1da177e4 5745{
52c03291
N		 5746 /* reshaping is quite different to recovery/resync so it is
5747 * handled quite separately ... here.
5748 *
5749 * On each call to sync_request, we gather one chunk worth of
5750 * destination stripes and flag them as expanding.
5751 * Then we find all the source stripes and request reads.
5752 * As the reads complete, handle_stripe will copy the data
5753 * into the destination stripe and release that stripe.
5754 */
d1688a6d 5755 struct r5conf *conf = mddev->private;
1da177e4 5756 struct stripe_head *sh;
db0505d3 5757 struct md_rdev *rdev;
ccfcc3c1 5758 sector_t first_sector, last_sector;
f416885e
N		 5759 int raid_disks = conf->previous_raid_disks;
5760 int data_disks = raid_disks - conf->max_degraded;
5761 int new_data_disks = conf->raid_disks - conf->max_degraded;
52c03291
N		 5762 int i;
5763 int dd_idx;
c8f517c4 5764 sector_t writepos, readpos, safepos;
ec32a2bd 5765 sector_t stripe_addr;
7a661381 5766 int reshape_sectors;
ab69ae12 5767 struct list_head stripes;
92140480 5768 sector_t retn;
52c03291 5769
fef9c61f
N		 5770 if (sector_nr == 0) {
5771 /* If restarting in the middle, skip the initial sectors */
2c810cdd 5772 if (mddev->reshape_backwards &&
fef9c61f
N		 5773 conf->reshape_progress < raid5_size(mddev, 0, 0)) {
5774 sector_nr = raid5_size(mddev, 0, 0)
5775 - conf->reshape_progress;
6cbd8148
N		 5776 } else if (mddev->reshape_backwards &&
5777 conf->reshape_progress == MaxSector) {
5778 /* shouldn't happen, but just in case, finish up.*/
5779 sector_nr = MaxSector;
2c810cdd 5780 } else if (!mddev->reshape_backwards &&
fef9c61f
N		 5781 conf->reshape_progress > 0)
5782 sector_nr = conf->reshape_progress;
f416885e 5783 sector_div(sector_nr, new_data_disks);
fef9c61f 5784 if (sector_nr) {
8dee7211
N		 5785 mddev->curr_resync_completed = sector_nr;
5786 sysfs_notify(&mddev->kobj, NULL, "sync_completed");
fef9c61f 5787 *skipped = 1;
92140480
N		 5788 retn = sector_nr;
5789 goto finish;
fef9c61f 5790 }
52c03291
N		 5791 }
5792
7a661381
N		 5793 /* We need to process a full chunk at a time.
5794 * If old and new chunk sizes differ, we need to process the
5795 * largest of these
5796 */
3cb5edf4
N		 5797
5798 reshape_sectors = max(conf->chunk_sectors, conf->prev_chunk_sectors);
7a661381 5799
b5254dd5
N		 5800 /* We update the metadata at least every 10 seconds, or when
5801 * the data about to be copied would over-write the source of
5802 * the data at the front of the range. i.e. one new_stripe
5803 * along from reshape_progress new_maps to after where
5804 * reshape_safe old_maps to
52c03291 5805 */
fef9c61f 5806 writepos = conf->reshape_progress;
f416885e 5807 sector_div(writepos, new_data_disks);
c8f517c4
N		 5808 readpos = conf->reshape_progress;
5809 sector_div(readpos, data_disks);
fef9c61f 5810 safepos = conf->reshape_safe;
f416885e 5811 sector_div(safepos, data_disks);
2c810cdd 5812 if (mddev->reshape_backwards) {
c74c0d76
N		 5813 BUG_ON(writepos < reshape_sectors);
5814 writepos -= reshape_sectors;
c8f517c4 5815 readpos += reshape_sectors;
7a661381 5816 safepos += reshape_sectors;
fef9c61f 5817 } else {
7a661381 5818 writepos += reshape_sectors;
c74c0d76
N		 5819 /* readpos and safepos are worst-case calculations.
5820 * A negative number is overly pessimistic, and causes
5821 * obvious problems for unsigned storage. So clip to 0.
5822 */
ed37d83e
N		 5823 readpos -= min_t(sector_t, reshape_sectors, readpos);
5824 safepos -= min_t(sector_t, reshape_sectors, safepos);
fef9c61f 5825 }
52c03291 5826
b5254dd5
N		 5827 /* Having calculated the 'writepos' possibly use it
5828 * to set 'stripe_addr' which is where we will write to.
5829 */
5830 if (mddev->reshape_backwards) {
5831 BUG_ON(conf->reshape_progress == 0);
5832 stripe_addr = writepos;
5833 BUG_ON((mddev->dev_sectors &
5834 ~((sector_t)reshape_sectors - 1))
5835 - reshape_sectors - stripe_addr
5836 != sector_nr);
5837 } else {
5838 BUG_ON(writepos != sector_nr + reshape_sectors);
5839 stripe_addr = sector_nr;
5840 }
5841
c8f517c4
N		 5842 /* 'writepos' is the most advanced device address we might write.
5843 * 'readpos' is the least advanced device address we might read.
5844 * 'safepos' is the least address recorded in the metadata as having
5845 * been reshaped.
b5254dd5
N		 5846 * If there is a min_offset_diff, these are adjusted either by
5847 * increasing the safepos/readpos if diff is negative, or
5848 * increasing writepos if diff is positive.
5849 * If 'readpos' is then behind 'writepos', there is no way that we can
c8f517c4
N		 5850 * ensure safety in the face of a crash - that must be done by userspace
5851 * making a backup of the data. So in that case there is no particular
5852 * rush to update metadata.
5853 * Otherwise if 'safepos' is behind 'writepos', then we really need to
5854 * update the metadata to advance 'safepos' to match 'readpos' so that
5855 * we can be safe in the event of a crash.
5856 * So we insist on updating metadata if safepos is behind writepos and
5857 * readpos is beyond writepos.
5858 * In any case, update the metadata every 10 seconds.
5859 * Maybe that number should be configurable, but I'm not sure it is
5860 * worth it.... maybe it could be a multiple of safemode_delay???
5861 */
b5254dd5
N		 5862 if (conf->min_offset_diff < 0) {
5863 safepos += -conf->min_offset_diff;
5864 readpos += -conf->min_offset_diff;
5865 } else
5866 writepos += conf->min_offset_diff;
5867
2c810cdd 5868 if ((mddev->reshape_backwards
c8f517c4
N		 5869 ? (safepos > writepos && readpos < writepos)
5870 : (safepos < writepos && readpos > writepos)) ||
5871 time_after(jiffies, conf->reshape_checkpoint + 10*HZ)) {
52c03291
N		 5872 /* Cannot proceed until we've updated the superblock... */
5873 wait_event(conf->wait_for_overlap,
c91abf5a
N		 5874 atomic_read(&conf->reshape_stripes)==0
5875 || test_bit(MD_RECOVERY_INTR, &mddev->recovery));
5876 if (atomic_read(&conf->reshape_stripes) != 0)
5877 return 0;
fef9c61f 5878 mddev->reshape_position = conf->reshape_progress;
75d3da43 5879 mddev->curr_resync_completed = sector_nr;
db0505d3
N		 5880 if (!mddev->reshape_backwards)
5881 /* Can update recovery_offset */
5882 rdev_for_each(rdev, mddev)
5883 if (rdev->raid_disk >= 0 &&
5884 !test_bit(Journal, &rdev->flags) &&
5885 !test_bit(In_sync, &rdev->flags) &&
5886 rdev->recovery_offset < sector_nr)
5887 rdev->recovery_offset = sector_nr;
5888
c8f517c4 5889 conf->reshape_checkpoint = jiffies;
2953079c 5890 set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
52c03291 5891 md_wakeup_thread(mddev->thread);
2953079c 5892 wait_event(mddev->sb_wait, mddev->sb_flags == 0 ||
c91abf5a
N		 5893 test_bit(MD_RECOVERY_INTR, &mddev->recovery));
5894 if (test_bit(MD_RECOVERY_INTR, &mddev->recovery))
5895 return 0;
52c03291 5896 spin_lock_irq(&conf->device_lock);
fef9c61f 5897 conf->reshape_safe = mddev->reshape_position;
52c03291
N		 5898 spin_unlock_irq(&conf->device_lock);
5899 wake_up(&conf->wait_for_overlap);
acb180b0 5900 sysfs_notify(&mddev->kobj, NULL, "sync_completed");
52c03291
N		 5901 }
5902
ab69ae12 5903 INIT_LIST_HEAD(&stripes);
7a661381 5904 for (i = 0; i < reshape_sectors; i += STRIPE_SECTORS) {
52c03291 5905 int j;
a9f326eb 5906 int skipped_disk = 0;
6d036f7d 5907 sh = raid5_get_active_stripe(conf, stripe_addr+i, 0, 0, 1);
52c03291
N		 5908 set_bit(STRIPE_EXPANDING, &sh->state);
5909 atomic_inc(&conf->reshape_stripes);
5910 /* If any of this stripe is beyond the end of the old
5911 * array, then we need to zero those blocks
5912 */
5913 for (j=sh->disks; j--;) {
5914 sector_t s;
5915 if (j == sh->pd_idx)
5916 continue;
f416885e 5917 if (conf->level == 6 &&
d0dabf7e 5918 j == sh->qd_idx)
f416885e 5919 continue;
6d036f7d 5920 s = raid5_compute_blocknr(sh, j, 0);
b522adcd 5921 if (s < raid5_size(mddev, 0, 0)) {
a9f326eb 5922 skipped_disk = 1;
52c03291
N		 5923 continue;
5924 }
5925 memset(page_address(sh->dev[j].page), 0, STRIPE_SIZE);
5926 set_bit(R5_Expanded, &sh->dev[j].flags);
5927 set_bit(R5_UPTODATE, &sh->dev[j].flags);
5928 }
a9f326eb 5929 if (!skipped_disk) {
52c03291
N		 5930 set_bit(STRIPE_EXPAND_READY, &sh->state);
5931 set_bit(STRIPE_HANDLE, &sh->state);
5932 }
ab69ae12 5933 list_add(&sh->lru, &stripes);
52c03291
N		 5934 }
5935 spin_lock_irq(&conf->device_lock);
2c810cdd 5936 if (mddev->reshape_backwards)
7a661381 5937 conf->reshape_progress -= reshape_sectors * new_data_disks;
fef9c61f 5938 else
7a661381 5939 conf->reshape_progress += reshape_sectors * new_data_disks;
52c03291
N		 5940 spin_unlock_irq(&conf->device_lock);
5941 /* Ok, those stripe are ready. We can start scheduling
5942 * reads on the source stripes.
5943 * The source stripes are determined by mapping the first and last
5944 * block on the destination stripes.
5945 */
52c03291 5946 first_sector =
ec32a2bd 5947 raid5_compute_sector(conf, stripe_addr*(new_data_disks),
911d4ee8 5948 1, &dd_idx, NULL);
52c03291 5949 last_sector =
0e6e0271 5950 raid5_compute_sector(conf, ((stripe_addr+reshape_sectors)
09c9e5fa 5951 * new_data_disks - 1),
911d4ee8 5952 1, &dd_idx, NULL);
58c0fed4
AN		 5953 if (last_sector >= mddev->dev_sectors)
5954 last_sector = mddev->dev_sectors - 1;
52c03291 5955 while (first_sector <= last_sector) {
6d036f7d 5956 sh = raid5_get_active_stripe(conf, first_sector, 1, 0, 1);
52c03291
N		 5957 set_bit(STRIPE_EXPAND_SOURCE, &sh->state);
5958 set_bit(STRIPE_HANDLE, &sh->state);
6d036f7d 5959 raid5_release_stripe(sh);
52c03291
N		 5960 first_sector += STRIPE_SECTORS;
5961 }
ab69ae12
N		 5962 /* Now that the sources are clearly marked, we can release
5963 * the destination stripes
5964 */
5965 while (!list_empty(&stripes)) {
5966 sh = list_entry(stripes.next, struct stripe_head, lru);
5967 list_del_init(&sh->lru);
6d036f7d 5968 raid5_release_stripe(sh);
ab69ae12 5969 }
c6207277
N		 5970 /* If this takes us to the resync_max point where we have to pause,
5971 * then we need to write out the superblock.
5972 */
7a661381 5973 sector_nr += reshape_sectors;
92140480
N		 5974 retn = reshape_sectors;
5975finish:
c5e19d90
N		 5976 if (mddev->curr_resync_completed > mddev->resync_max ||
5977 (sector_nr - mddev->curr_resync_completed) * 2
c03f6a19 5978 >= mddev->resync_max - mddev->curr_resync_completed) {
c6207277
N		 5979 /* Cannot proceed until we've updated the superblock... */
5980 wait_event(conf->wait_for_overlap,
c91abf5a
N		 5981 atomic_read(&conf->reshape_stripes) == 0
5982 || test_bit(MD_RECOVERY_INTR, &mddev->recovery));
5983 if (atomic_read(&conf->reshape_stripes) != 0)
5984 goto ret;
fef9c61f 5985 mddev->reshape_position = conf->reshape_progress;
75d3da43 5986 mddev->curr_resync_completed = sector_nr;
db0505d3
N		 5987 if (!mddev->reshape_backwards)
5988 /* Can update recovery_offset */
5989 rdev_for_each(rdev, mddev)
5990 if (rdev->raid_disk >= 0 &&
5991 !test_bit(Journal, &rdev->flags) &&
5992 !test_bit(In_sync, &rdev->flags) &&
5993 rdev->recovery_offset < sector_nr)
5994 rdev->recovery_offset = sector_nr;
c8f517c4 5995 conf->reshape_checkpoint = jiffies;
2953079c 5996 set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
c6207277
N		 5997 md_wakeup_thread(mddev->thread);
5998 wait_event(mddev->sb_wait,
2953079c 5999 !test_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags)
c91abf5a
N		 6000 || test_bit(MD_RECOVERY_INTR, &mddev->recovery));
6001 if (test_bit(MD_RECOVERY_INTR, &mddev->recovery))
6002 goto ret;
c6207277 6003 spin_lock_irq(&conf->device_lock);
fef9c61f 6004 conf->reshape_safe = mddev->reshape_position;
c6207277
N		 6005 spin_unlock_irq(&conf->device_lock);
6006 wake_up(&conf->wait_for_overlap);
acb180b0 6007 sysfs_notify(&mddev->kobj, NULL, "sync_completed");
c6207277 6008 }
c91abf5a 6009ret:
92140480 6010 return retn;
52c03291
N		 6011}
6012
849674e4
SL		 6013static inline sector_t raid5_sync_request(struct mddev *mddev, sector_t sector_nr,
6014 int *skipped)
52c03291 6015{
d1688a6d 6016 struct r5conf *conf = mddev->private;
52c03291 6017 struct stripe_head *sh;
58c0fed4 6018 sector_t max_sector = mddev->dev_sectors;
57dab0bd 6019 sector_t sync_blocks;
16a53ecc
N		 6020 int still_degraded = 0;
6021 int i;
1da177e4 6022
72626685 6023 if (sector_nr >= max_sector) {
1da177e4 6024 /* just being told to finish up .. nothing much to do */
cea9c228 6025
29269553
N		 6026 if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)) {
6027 end_reshape(conf);
6028 return 0;
6029 }
72626685
N		 6030
6031 if (mddev->curr_resync < max_sector) /* aborted */
e64e4018
AS		 6032 md_bitmap_end_sync(mddev->bitmap, mddev->curr_resync,
6033 &sync_blocks, 1);
16a53ecc 6034 else /* completed sync */
72626685 6035 conf->fullsync = 0;
e64e4018 6036 md_bitmap_close_sync(mddev->bitmap);
72626685 6037
1da177e4
LT		 6038 return 0;
6039 }
ccfcc3c1 6040
64bd660b
N		 6041 /* Allow raid5_quiesce to complete */
6042 wait_event(conf->wait_for_overlap, conf->quiesce != 2);
6043
52c03291
N		 6044 if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
6045 return reshape_request(mddev, sector_nr, skipped);
f6705578 6046
c6207277
N		 6047 /* No need to check resync_max as we never do more than one
6048 * stripe, and as resync_max will always be on a chunk boundary,
6049 * if the check in md_do_sync didn't fire, there is no chance
6050 * of overstepping resync_max here
6051 */
6052
16a53ecc 6053 /* if there is too many failed drives and we are trying
1da177e4
LT		 6054 * to resync, then assert that we are finished, because there is
6055 * nothing we can do.
6056 */
3285edf1 6057 if (mddev->degraded >= conf->max_degraded &&
16a53ecc 6058 test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) {
58c0fed4 6059 sector_t rv = mddev->dev_sectors - sector_nr;
57afd89f 6060 *skipped = 1;
1da177e4
LT		 6061 return rv;
6062 }
6f608040 6063 if (!test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery) &&
6064 !conf->fullsync &&
e64e4018 6065 !md_bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, 1) &&
6f608040 6066 sync_blocks >= STRIPE_SECTORS) {
72626685
N		 6067 /* we can skip this block, and probably more */
6068 sync_blocks /= STRIPE_SECTORS;
6069 *skipped = 1;
6070 return sync_blocks * STRIPE_SECTORS; /* keep things rounded to whole stripes */
6071 }
1da177e4 6072
e64e4018 6073 md_bitmap_cond_end_sync(mddev->bitmap, sector_nr, false);
b47490c9 6074
6d036f7d 6075 sh = raid5_get_active_stripe(conf, sector_nr, 0, 1, 0);
1da177e4 6076 if (sh == NULL) {
6d036f7d 6077 sh = raid5_get_active_stripe(conf, sector_nr, 0, 0, 0);
1da177e4 6078 /* make sure we don't swamp the stripe cache if someone else
16a53ecc 6079 * is trying to get access
1da177e4 6080 */
66c006a5 6081 schedule_timeout_uninterruptible(1);
1da177e4 6082 }
16a53ecc 6083 /* Need to check if array will still be degraded after recovery/resync
16d9cfab
EM		 6084 * Note in case of > 1 drive failures it's possible we're rebuilding
6085 * one drive while leaving another faulty drive in array.
16a53ecc 6086 */
16d9cfab
EM		 6087 rcu_read_lock();
6088 for (i = 0; i < conf->raid_disks; i++) {
6aa7de05 6089 struct md_rdev *rdev = READ_ONCE(conf->disks[i].rdev);
16d9cfab
EM		 6090
6091 if (rdev == NULL || test_bit(Faulty, &rdev->flags))
16a53ecc 6092 still_degraded = 1;
16d9cfab
EM		 6093 }
6094 rcu_read_unlock();
16a53ecc 6095
e64e4018 6096 md_bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, still_degraded);
16a53ecc 6097
83206d66 6098 set_bit(STRIPE_SYNC_REQUESTED, &sh->state);
053f5b65 6099 set_bit(STRIPE_HANDLE, &sh->state);
1da177e4 6100
6d036f7d 6101 raid5_release_stripe(sh);
1da177e4
LT		 6102
6103 return STRIPE_SECTORS;
6104}
6105
0472a42b
N		 6106static int retry_aligned_read(struct r5conf *conf, struct bio *raid_bio,
6107 unsigned int offset)
46031f9a
RBJ		 6108{
6109 /* We may not be able to submit a whole bio at once as there
6110 * may not be enough stripe_heads available.
6111 * We cannot pre-allocate enough stripe_heads as we may need
6112 * more than exist in the cache (if we allow ever large chunks).
6113 * So we do one stripe head at a time and record in
6114 * ->bi_hw_segments how many have been done.
6115 *
6116 * We *know* that this entire raid_bio is in one chunk, so
6117 * it will be only one 'dd_idx' and only need one call to raid5_compute_sector.
6118 */
6119 struct stripe_head *sh;
911d4ee8 6120 int dd_idx;
46031f9a
RBJ		 6121 sector_t sector, logical_sector, last_sector;
6122 int scnt = 0;
46031f9a
RBJ		 6123 int handled = 0;
6124
4f024f37
KO		 6125 logical_sector = raid_bio->bi_iter.bi_sector &
6126 ~((sector_t)STRIPE_SECTORS-1);
112bf897 6127 sector = raid5_compute_sector(conf, logical_sector,
911d4ee8 6128 0, &dd_idx, NULL);
f73a1c7d 6129 last_sector = bio_end_sector(raid_bio);
46031f9a
RBJ		 6130
6131 for (; logical_sector < last_sector;
387bb173
NB		 6132 logical_sector += STRIPE_SECTORS,
6133 sector += STRIPE_SECTORS,
6134 scnt++) {
46031f9a 6135
0472a42b 6136 if (scnt < offset)
46031f9a
RBJ		 6137 /* already done this stripe */
6138 continue;
6139
6d036f7d 6140 sh = raid5_get_active_stripe(conf, sector, 0, 1, 1);
46031f9a
RBJ		 6141
6142 if (!sh) {
6143 /* failed to get a stripe - must wait */
46031f9a 6144 conf->retry_read_aligned = raid_bio;
0472a42b 6145 conf->retry_read_offset = scnt;
46031f9a
RBJ		 6146 return handled;
6147 }
6148
da41ba65 6149 if (!add_stripe_bio(sh, raid_bio, dd_idx, 0, 0)) {
6d036f7d 6150 raid5_release_stripe(sh);
387bb173 6151 conf->retry_read_aligned = raid_bio;
0472a42b 6152 conf->retry_read_offset = scnt;
387bb173
NB		 6153 return handled;
6154 }
6155
3f9e7c14 6156 set_bit(R5_ReadNoMerge, &sh->dev[dd_idx].flags);
36d1c647 6157 handle_stripe(sh);
6d036f7d 6158 raid5_release_stripe(sh);
46031f9a
RBJ		 6159 handled++;
6160 }
016c76ac
N		 6161
6162 bio_endio(raid_bio);
6163
46031f9a 6164 if (atomic_dec_and_test(&conf->active_aligned_reads))
b1b46486 6165 wake_up(&conf->wait_for_quiescent);
46031f9a
RBJ		 6166 return handled;
6167}
6168
bfc90cb0 6169static int handle_active_stripes(struct r5conf *conf, int group,
566c09c5
SL		 6170 struct r5worker *worker,
6171 struct list_head *temp_inactive_list)
efcd487c
CH		 6172 __releases(&conf->device_lock)
6173 __acquires(&conf->device_lock)
46a06401
SL		 6174{
6175 struct stripe_head *batch[MAX_STRIPE_BATCH], *sh;
566c09c5
SL		 6176 int i, batch_size = 0, hash;
6177 bool release_inactive = false;
46a06401
SL		 6178
6179 while (batch_size < MAX_STRIPE_BATCH &&
851c30c9 6180 (sh = __get_priority_stripe(conf, group)) != NULL)
46a06401
SL		 6181 batch[batch_size++] = sh;
6182
566c09c5
SL		 6183 if (batch_size == 0) {
6184 for (i = 0; i < NR_STRIPE_HASH_LOCKS; i++)
6185 if (!list_empty(temp_inactive_list + i))
6186 break;
a8c34f91
SL		 6187 if (i == NR_STRIPE_HASH_LOCKS) {
6188 spin_unlock_irq(&conf->device_lock);
1532d9e8 6189 log_flush_stripe_to_raid(conf);
a8c34f91 6190 spin_lock_irq(&conf->device_lock);
566c09c5 6191 return batch_size;
a8c34f91 6192 }
566c09c5
SL		 6193 release_inactive = true;
6194 }
46a06401
SL		 6195 spin_unlock_irq(&conf->device_lock);
6196
566c09c5
SL		 6197 release_inactive_stripe_list(conf, temp_inactive_list,
6198 NR_STRIPE_HASH_LOCKS);
6199
a8c34f91 6200 r5l_flush_stripe_to_raid(conf->log);
566c09c5
SL		 6201 if (release_inactive) {
6202 spin_lock_irq(&conf->device_lock);
6203 return 0;
6204 }
6205
46a06401
SL		 6206 for (i = 0; i < batch_size; i++)
6207 handle_stripe(batch[i]);
ff875738 6208 log_write_stripe_run(conf);
46a06401
SL		 6209
6210 cond_resched();
6211
6212 spin_lock_irq(&conf->device_lock);
566c09c5
SL		 6213 for (i = 0; i < batch_size; i++) {
6214 hash = batch[i]->hash_lock_index;
6215 __release_stripe(conf, batch[i], &temp_inactive_list[hash]);
6216 }
46a06401
SL		 6217 return batch_size;
6218}
46031f9a 6219
851c30c9
SL		 6220static void raid5_do_work(struct work_struct *work)
6221{
6222 struct r5worker *worker = container_of(work, struct r5worker, work);
6223 struct r5worker_group *group = worker->group;
6224 struct r5conf *conf = group->conf;
16d997b7 6225 struct mddev *mddev = conf->mddev;
851c30c9
SL		 6226 int group_id = group - conf->worker_groups;
6227 int handled;
6228 struct blk_plug plug;
6229
6230 pr_debug("+++ raid5worker active\n");
6231
6232 blk_start_plug(&plug);
6233 handled = 0;
6234 spin_lock_irq(&conf->device_lock);
6235 while (1) {
6236 int batch_size, released;
6237
566c09c5 6238 released = release_stripe_list(conf, worker->temp_inactive_list);
851c30c9 6239
566c09c5
SL		 6240 batch_size = handle_active_stripes(conf, group_id, worker,
6241 worker->temp_inactive_list);
bfc90cb0 6242 worker->working = false;
851c30c9
SL		 6243 if (!batch_size && !released)
6244 break;
6245 handled += batch_size;
16d997b7
N		 6246 wait_event_lock_irq(mddev->sb_wait,
6247 !test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags),
6248 conf->device_lock);
851c30c9
SL		 6249 }
6250 pr_debug("%d stripes handled\n", handled);
6251
6252 spin_unlock_irq(&conf->device_lock);
7e96d559 6253
9c72a18e
SL		 6254 flush_deferred_bios(conf);
6255
6256 r5l_flush_stripe_to_raid(conf->log);
6257
7e96d559 6258 async_tx_issue_pending_all();
851c30c9
SL		 6259 blk_finish_plug(&plug);
6260
6261 pr_debug("--- raid5worker inactive\n");
6262}
6263
1da177e4
LT		 6264/*
6265 * This is our raid5 kernel thread.
6266 *
6267 * We scan the hash table for stripes which can be handled now.
6268 * During the scan, completed stripes are saved for us by the interrupt
6269 * handler, so that they will not have to wait for our next wakeup.
6270 */
4ed8731d 6271static void raid5d(struct md_thread *thread)
1da177e4 6272{
4ed8731d 6273 struct mddev *mddev = thread->mddev;
d1688a6d 6274 struct r5conf *conf = mddev->private;
1da177e4 6275 int handled;
e1dfa0a2 6276 struct blk_plug plug;
1da177e4 6277
45b4233c 6278 pr_debug("+++ raid5d active\n");
1da177e4
LT		 6279
6280 md_check_recovery(mddev);
1da177e4 6281
e1dfa0a2 6282 blk_start_plug(&plug);
1da177e4
LT		 6283 handled = 0;
6284 spin_lock_irq(&conf->device_lock);
6285 while (1) {
46031f9a 6286 struct bio *bio;
773ca82f 6287 int batch_size, released;
0472a42b 6288 unsigned int offset;
773ca82f 6289
566c09c5 6290 released = release_stripe_list(conf, conf->temp_inactive_list);
edbe83ab
N		 6291 if (released)
6292 clear_bit(R5_DID_ALLOC, &conf->cache_state);
1da177e4 6293
0021b7bc 6294 if (
7c13edc8
N		 6295 !list_empty(&conf->bitmap_list)) {
6296 /* Now is a good time to flush some bitmap updates */
6297 conf->seq_flush++;
700e432d 6298 spin_unlock_irq(&conf->device_lock);
e64e4018 6299 md_bitmap_unplug(mddev->bitmap);
700e432d 6300 spin_lock_irq(&conf->device_lock);
7c13edc8 6301 conf->seq_write = conf->seq_flush;
566c09c5 6302 activate_bit_delay(conf, conf->temp_inactive_list);
72626685 6303 }
0021b7bc 6304 raid5_activate_delayed(conf);
72626685 6305
0472a42b 6306 while ((bio = remove_bio_from_retry(conf, &offset))) {
46031f9a
RBJ		 6307 int ok;
6308 spin_unlock_irq(&conf->device_lock);
0472a42b 6309 ok = retry_aligned_read(conf, bio, offset);
46031f9a
RBJ		 6310 spin_lock_irq(&conf->device_lock);
6311 if (!ok)
6312 break;
6313 handled++;
6314 }
6315
566c09c5
SL		 6316 batch_size = handle_active_stripes(conf, ANY_GROUP, NULL,
6317 conf->temp_inactive_list);
773ca82f 6318 if (!batch_size && !released)
1da177e4 6319 break;
46a06401 6320 handled += batch_size;
1da177e4 6321
2953079c 6322 if (mddev->sb_flags & ~(1 << MD_SB_CHANGE_PENDING)) {
46a06401 6323 spin_unlock_irq(&conf->device_lock);
de393cde 6324 md_check_recovery(mddev);
46a06401
SL		 6325 spin_lock_irq(&conf->device_lock);
6326 }
1da177e4 6327 }
45b4233c 6328 pr_debug("%d stripes handled\n", handled);
1da177e4
LT		 6329
6330 spin_unlock_irq(&conf->device_lock);
2d5b569b
N		 6331 if (test_and_clear_bit(R5_ALLOC_MORE, &conf->cache_state) &&
6332 mutex_trylock(&conf->cache_size_mutex)) {
edbe83ab
N		 6333 grow_one_stripe(conf, __GFP_NOWARN);
6334 /* Set flag even if allocation failed. This helps
6335 * slow down allocation requests when mem is short
6336 */
6337 set_bit(R5_DID_ALLOC, &conf->cache_state);
2d5b569b 6338 mutex_unlock(&conf->cache_size_mutex);
edbe83ab 6339 }
1da177e4 6340
765d704d
SL		 6341 flush_deferred_bios(conf);
6342
0576b1c6
SL		 6343 r5l_flush_stripe_to_raid(conf->log);
6344
c9f21aaf 6345 async_tx_issue_pending_all();
e1dfa0a2 6346 blk_finish_plug(&plug);
1da177e4 6347
45b4233c 6348 pr_debug("--- raid5d inactive\n");
1da177e4
LT		 6349}
6350
3f294f4f 6351static ssize_t
fd01b88c 6352raid5_show_stripe_cache_size(struct mddev *mddev, char *page)
3f294f4f 6353{
7b1485ba
N		 6354 struct r5conf *conf;
6355 int ret = 0;
6356 spin_lock(&mddev->lock);
6357 conf = mddev->private;
96de1e66 6358 if (conf)
edbe83ab 6359 ret = sprintf(page, "%d\n", conf->min_nr_stripes);
7b1485ba
N		 6360 spin_unlock(&mddev->lock);
6361 return ret;
3f294f4f
N		 6362}
6363
c41d4ac4 6364int
fd01b88c 6365raid5_set_cache_size(struct mddev *mddev, int size)
3f294f4f 6366{
483cbbed 6367 int result = 0;
d1688a6d 6368 struct r5conf *conf = mddev->private;
b5470dc5 6369
c41d4ac4 6370 if (size <= 16 || size > 32768)
3f294f4f 6371 return -EINVAL;
486f0644 6372
edbe83ab 6373 conf->min_nr_stripes = size;
2d5b569b 6374 mutex_lock(&conf->cache_size_mutex);
486f0644
N		 6375 while (size < conf->max_nr_stripes &&
6376 drop_one_stripe(conf))
6377 ;
2d5b569b 6378 mutex_unlock(&conf->cache_size_mutex);
486f0644 6379
2214c260 6380 md_allow_write(mddev);
486f0644 6381
2d5b569b 6382 mutex_lock(&conf->cache_size_mutex);
486f0644 6383 while (size > conf->max_nr_stripes)
483cbbed
AN		 6384 if (!grow_one_stripe(conf, GFP_KERNEL)) {
6385 conf->min_nr_stripes = conf->max_nr_stripes;
6386 result = -ENOMEM;
486f0644 6387 break;
483cbbed 6388 }
2d5b569b 6389 mutex_unlock(&conf->cache_size_mutex);
486f0644 6390
483cbbed 6391 return result;
c41d4ac4
N		 6392}
6393EXPORT_SYMBOL(raid5_set_cache_size);
6394
6395static ssize_t
fd01b88c 6396raid5_store_stripe_cache_size(struct mddev *mddev, const char *page, size_t len)
c41d4ac4 6397{
6791875e 6398 struct r5conf *conf;
c41d4ac4
N		 6399 unsigned long new;
6400 int err;
6401
6402 if (len >= PAGE_SIZE)
6403 return -EINVAL;
b29bebd6 6404 if (kstrtoul(page, 10, &new))
c41d4ac4 6405 return -EINVAL;
6791875e 6406 err = mddev_lock(mddev);
c41d4ac4
N		 6407 if (err)
6408 return err;
6791875e
N		 6409 conf = mddev->private;
6410 if (!conf)
6411 err = -ENODEV;
6412 else
6413 err = raid5_set_cache_size(mddev, new);
6414 mddev_unlock(mddev);
6415
6416 return err ?: len;
3f294f4f 6417}
007583c9 6418
96de1e66
N		 6419static struct md_sysfs_entry
6420raid5_stripecache_size = __ATTR(stripe_cache_size, S_IRUGO | S_IWUSR,
6421 raid5_show_stripe_cache_size,
6422 raid5_store_stripe_cache_size);
3f294f4f 6423
d06f191f
MS		 6424static ssize_t
6425raid5_show_rmw_level(struct mddev *mddev, char *page)
6426{
6427 struct r5conf *conf = mddev->private;
6428 if (conf)
6429 return sprintf(page, "%d\n", conf->rmw_level);
6430 else
6431 return 0;
6432}
6433
6434static ssize_t
6435raid5_store_rmw_level(struct mddev *mddev, const char *page, size_t len)
6436{
6437 struct r5conf *conf = mddev->private;
6438 unsigned long new;
6439
6440 if (!conf)
6441 return -ENODEV;
6442
6443 if (len >= PAGE_SIZE)
6444 return -EINVAL;
6445
6446 if (kstrtoul(page, 10, &new))
6447 return -EINVAL;
6448
6449 if (new != PARITY_DISABLE_RMW && !raid6_call.xor_syndrome)
6450 return -EINVAL;
6451
6452 if (new != PARITY_DISABLE_RMW &&
6453 new != PARITY_ENABLE_RMW &&
6454 new != PARITY_PREFER_RMW)
6455 return -EINVAL;
6456
6457 conf->rmw_level = new;
6458 return len;
6459}
6460
6461static struct md_sysfs_entry
6462raid5_rmw_level = __ATTR(rmw_level, S_IRUGO | S_IWUSR,
6463 raid5_show_rmw_level,
6464 raid5_store_rmw_level);
6465
6466
8b3e6cdc 6467static ssize_t
fd01b88c 6468raid5_show_preread_threshold(struct mddev *mddev, char *page)
8b3e6cdc 6469{
7b1485ba
N		 6470 struct r5conf *conf;
6471 int ret = 0;
6472 spin_lock(&mddev->lock);
6473 conf = mddev->private;
8b3e6cdc 6474 if (conf)
7b1485ba
N		 6475 ret = sprintf(page, "%d\n", conf->bypass_threshold);
6476 spin_unlock(&mddev->lock);
6477 return ret;
8b3e6cdc
DW		 6478}
6479
6480static ssize_t
fd01b88c 6481raid5_store_preread_threshold(struct mddev *mddev, const char *page, size_t len)
8b3e6cdc 6482{
6791875e 6483 struct r5conf *conf;
4ef197d8 6484 unsigned long new;
6791875e
N		 6485 int err;
6486
8b3e6cdc
DW		 6487 if (len >= PAGE_SIZE)
6488 return -EINVAL;
b29bebd6 6489 if (kstrtoul(page, 10, &new))
8b3e6cdc 6490 return -EINVAL;
6791875e
N		 6491
6492 err = mddev_lock(mddev);
6493 if (err)
6494 return err;
6495 conf = mddev->private;
6496 if (!conf)
6497 err = -ENODEV;
edbe83ab 6498 else if (new > conf->min_nr_stripes)
6791875e
N		 6499 err = -EINVAL;
6500 else
6501 conf->bypass_threshold = new;
6502 mddev_unlock(mddev);
6503 return err ?: len;
8b3e6cdc
DW		 6504}
6505
6506static struct md_sysfs_entry
6507raid5_preread_bypass_threshold = __ATTR(preread_bypass_threshold,
6508 S_IRUGO | S_IWUSR,
6509 raid5_show_preread_threshold,
6510 raid5_store_preread_threshold);
6511
d592a996
SL		 6512static ssize_t
6513raid5_show_skip_copy(struct mddev *mddev, char *page)
6514{
7b1485ba
N		 6515 struct r5conf *conf;
6516 int ret = 0;
6517 spin_lock(&mddev->lock);
6518 conf = mddev->private;
d592a996 6519 if (conf)
7b1485ba
N		 6520 ret = sprintf(page, "%d\n", conf->skip_copy);
6521 spin_unlock(&mddev->lock);
6522 return ret;
d592a996
SL		 6523}
6524
6525static ssize_t
6526raid5_store_skip_copy(struct mddev *mddev, const char *page, size_t len)
6527{
6791875e 6528 struct r5conf *conf;
d592a996 6529 unsigned long new;
6791875e
N		 6530 int err;
6531
d592a996
SL		 6532 if (len >= PAGE_SIZE)
6533 return -EINVAL;
d592a996
SL		 6534 if (kstrtoul(page, 10, &new))
6535 return -EINVAL;
6536 new = !!new;
6791875e
N		 6537
6538 err = mddev_lock(mddev);
6539 if (err)
6540 return err;
6541 conf = mddev->private;
6542 if (!conf)
6543 err = -ENODEV;
6544 else if (new != conf->skip_copy) {
6545 mddev_suspend(mddev);
6546 conf->skip_copy = new;
6547 if (new)
dc3b17cc 6548 mddev->queue->backing_dev_info->capabilities |=
6791875e
N		 6549 BDI_CAP_STABLE_WRITES;
6550 else
dc3b17cc 6551 mddev->queue->backing_dev_info->capabilities &=
6791875e
N		 6552 ~BDI_CAP_STABLE_WRITES;
6553 mddev_resume(mddev);
6554 }
6555 mddev_unlock(mddev);
6556 return err ?: len;
d592a996
SL		 6557}
6558
6559static struct md_sysfs_entry
6560raid5_skip_copy = __ATTR(skip_copy, S_IRUGO | S_IWUSR,
6561 raid5_show_skip_copy,
6562 raid5_store_skip_copy);
6563
3f294f4f 6564static ssize_t
fd01b88c 6565stripe_cache_active_show(struct mddev *mddev, char *page)
3f294f4f 6566{
d1688a6d 6567 struct r5conf *conf = mddev->private;
96de1e66
N		 6568 if (conf)
6569 return sprintf(page, "%d\n", atomic_read(&conf->active_stripes));
6570 else
6571 return 0;
3f294f4f
N		 6572}
6573
96de1e66
N		 6574static struct md_sysfs_entry
6575raid5_stripecache_active = __ATTR_RO(stripe_cache_active);
3f294f4f 6576
b721420e
SL		 6577static ssize_t
6578raid5_show_group_thread_cnt(struct mddev *mddev, char *page)
6579{
7b1485ba
N		 6580 struct r5conf *conf;
6581 int ret = 0;
6582 spin_lock(&mddev->lock);
6583 conf = mddev->private;
b721420e 6584 if (conf)
7b1485ba
N		 6585 ret = sprintf(page, "%d\n", conf->worker_cnt_per_group);
6586 spin_unlock(&mddev->lock);
6587 return ret;
b721420e
SL		 6588}
6589
60aaf933 6590static int alloc_thread_groups(struct r5conf *conf, int cnt,
6591 int *group_cnt,
6592 int *worker_cnt_per_group,
6593 struct r5worker_group **worker_groups);
b721420e
SL		 6594static ssize_t
6595raid5_store_group_thread_cnt(struct mddev *mddev, const char *page, size_t len)
6596{
6791875e 6597 struct r5conf *conf;
7d5d7b50 6598 unsigned int new;
b721420e 6599 int err;
60aaf933 6600 struct r5worker_group *new_groups, *old_groups;
6601 int group_cnt, worker_cnt_per_group;
b721420e
SL		 6602
6603 if (len >= PAGE_SIZE)
6604 return -EINVAL;
7d5d7b50
SL		 6605 if (kstrtouint(page, 10, &new))
6606 return -EINVAL;
6607 /* 8192 should be big enough */
6608 if (new > 8192)
b721420e
SL		 6609 return -EINVAL;
6610
6791875e
N		 6611 err = mddev_lock(mddev);
6612 if (err)
6613 return err;
6614 conf = mddev->private;
6615 if (!conf)
6616 err = -ENODEV;
6617 else if (new != conf->worker_cnt_per_group) {
6618 mddev_suspend(mddev);
b721420e 6619
6791875e
N		 6620 old_groups = conf->worker_groups;
6621 if (old_groups)
6622 flush_workqueue(raid5_wq);
d206dcfa 6623
6791875e
N		 6624 err = alloc_thread_groups(conf, new,
6625 &group_cnt, &worker_cnt_per_group,
6626 &new_groups);
6627 if (!err) {
6628 spin_lock_irq(&conf->device_lock);
6629 conf->group_cnt = group_cnt;
6630 conf->worker_cnt_per_group = worker_cnt_per_group;
6631 conf->worker_groups = new_groups;
6632 spin_unlock_irq(&conf->device_lock);
b721420e 6633
6791875e
N		 6634 if (old_groups)
6635 kfree(old_groups[0].workers);
6636 kfree(old_groups);
6637 }
6638 mddev_resume(mddev);
b721420e 6639 }
6791875e 6640 mddev_unlock(mddev);
b721420e 6641
6791875e 6642 return err ?: len;
b721420e
SL		 6643}
6644
6645static struct md_sysfs_entry
6646raid5_group_thread_cnt = __ATTR(group_thread_cnt, S_IRUGO | S_IWUSR,
6647 raid5_show_group_thread_cnt,
6648 raid5_store_group_thread_cnt);
6649
007583c9 6650static struct attribute *raid5_attrs[] = {
3f294f4f
N		 6651 &raid5_stripecache_size.attr,
6652 &raid5_stripecache_active.attr,
8b3e6cdc 6653 &raid5_preread_bypass_threshold.attr,
b721420e 6654 &raid5_group_thread_cnt.attr,
d592a996 6655 &raid5_skip_copy.attr,
d06f191f 6656 &raid5_rmw_level.attr,
2c7da14b 6657 &r5c_journal_mode.attr,
a596d086 6658 &ppl_write_hint.attr,
3f294f4f
N		 6659 NULL,
6660};
007583c9
N		 6661static struct attribute_group raid5_attrs_group = {
6662 .name = NULL,
6663 .attrs = raid5_attrs,
3f294f4f
N		 6664};
6665
60aaf933 6666static int alloc_thread_groups(struct r5conf *conf, int cnt,
6667 int *group_cnt,
6668 int *worker_cnt_per_group,
6669 struct r5worker_group **worker_groups)
851c30c9 6670{
566c09c5 6671 int i, j, k;
851c30c9
SL		 6672 ssize_t size;
6673 struct r5worker *workers;
6674
60aaf933 6675 *worker_cnt_per_group = cnt;
851c30c9 6676 if (cnt == 0) {
60aaf933 6677 *group_cnt = 0;
6678 *worker_groups = NULL;
851c30c9
SL		 6679 return 0;
6680 }
60aaf933 6681 *group_cnt = num_possible_nodes();
851c30c9 6682 size = sizeof(struct r5worker) * cnt;
6396bb22
KC		 6683 workers = kcalloc(size, *group_cnt, GFP_NOIO);
6684 *worker_groups = kcalloc(*group_cnt, sizeof(struct r5worker_group),
6685 GFP_NOIO);
60aaf933 6686 if (!*worker_groups || !workers) {
851c30c9 6687 kfree(workers);
60aaf933 6688 kfree(*worker_groups);
851c30c9
SL		 6689 return -ENOMEM;
6690 }
6691
60aaf933 6692 for (i = 0; i < *group_cnt; i++) {
851c30c9
SL		 6693 struct r5worker_group *group;
6694
0c775d52 6695 group = &(*worker_groups)[i];
851c30c9 6696 INIT_LIST_HEAD(&group->handle_list);
535ae4eb 6697 INIT_LIST_HEAD(&group->loprio_list);
851c30c9
SL		 6698 group->conf = conf;
6699 group->workers = workers + i * cnt;
6700
6701 for (j = 0; j < cnt; j++) {
566c09c5
SL		 6702 struct r5worker *worker = group->workers + j;
6703 worker->group = group;
6704 INIT_WORK(&worker->work, raid5_do_work);
6705
6706 for (k = 0; k < NR_STRIPE_HASH_LOCKS; k++)
6707 INIT_LIST_HEAD(worker->temp_inactive_list + k);
851c30c9
SL		 6708 }
6709 }
6710
6711 return 0;
6712}
6713
6714static void free_thread_groups(struct r5conf *conf)
6715{
6716 if (conf->worker_groups)
6717 kfree(conf->worker_groups[0].workers);
6718 kfree(conf->worker_groups);
6719 conf->worker_groups = NULL;
6720}
6721
80c3a6ce 6722static sector_t
fd01b88c 6723raid5_size(struct mddev *mddev, sector_t sectors, int raid_disks)
80c3a6ce 6724{
d1688a6d 6725 struct r5conf *conf = mddev->private;
80c3a6ce
DW		 6726
6727 if (!sectors)
6728 sectors = mddev->dev_sectors;
5e5e3e78 6729 if (!raid_disks)
7ec05478 6730 /* size is defined by the smallest of previous and new size */
5e5e3e78 6731 raid_disks = min(conf->raid_disks, conf->previous_raid_disks);
80c3a6ce 6732
3cb5edf4
N		 6733 sectors &= ~((sector_t)conf->chunk_sectors - 1);
6734 sectors &= ~((sector_t)conf->prev_chunk_sectors - 1);
80c3a6ce
DW		 6735 return sectors * (raid_disks - conf->max_degraded);
6736}
6737
789b5e03
ON		 6738static void free_scratch_buffer(struct r5conf *conf, struct raid5_percpu *percpu)
6739{
6740 safe_put_page(percpu->spare_page);
789b5e03 6741 percpu->spare_page = NULL;
b330e6a4 6742 kvfree(percpu->scribble);
789b5e03
ON		 6743 percpu->scribble = NULL;
6744}
6745
6746static int alloc_scratch_buffer(struct r5conf *conf, struct raid5_percpu *percpu)
6747{
b330e6a4 6748 if (conf->level == 6 && !percpu->spare_page) {
789b5e03 6749 percpu->spare_page = alloc_page(GFP_KERNEL);
b330e6a4
KO		 6750 if (!percpu->spare_page)
6751 return -ENOMEM;
6752 }
6753
6754 if (scribble_alloc(percpu,
6755 max(conf->raid_disks,
6756 conf->previous_raid_disks),
6757 max(conf->chunk_sectors,
6758 conf->prev_chunk_sectors)
6759 / STRIPE_SECTORS,
6760 GFP_KERNEL)) {
789b5e03
ON		 6761 free_scratch_buffer(conf, percpu);
6762 return -ENOMEM;
6763 }
6764
6765 return 0;
6766}
6767
29c6d1bb 6768static int raid456_cpu_dead(unsigned int cpu, struct hlist_node *node)
36d1c647 6769{
29c6d1bb
SAS		 6770 struct r5conf *conf = hlist_entry_safe(node, struct r5conf, node);
6771
6772 free_scratch_buffer(conf, per_cpu_ptr(conf->percpu, cpu));
6773 return 0;
6774}
36d1c647 6775
29c6d1bb
SAS		 6776static void raid5_free_percpu(struct r5conf *conf)
6777{
36d1c647
DW		 6778 if (!conf->percpu)
6779 return;
6780
29c6d1bb 6781 cpuhp_state_remove_instance(CPUHP_MD_RAID5_PREPARE, &conf->node);
36d1c647
DW		 6782 free_percpu(conf->percpu);
6783}
6784
d1688a6d 6785static void free_conf(struct r5conf *conf)
95fc17aa 6786{
d7bd398e
SL		 6787 int i;
6788
ff875738
AP		 6789 log_exit(conf);
6790
565e0450 6791 unregister_shrinker(&conf->shrinker);
851c30c9 6792 free_thread_groups(conf);
95fc17aa 6793 shrink_stripes(conf);
36d1c647 6794 raid5_free_percpu(conf);
d7bd398e
SL		 6795 for (i = 0; i < conf->pool_size; i++)
6796 if (conf->disks[i].extra_page)
6797 put_page(conf->disks[i].extra_page);
95fc17aa 6798 kfree(conf->disks);
afeee514 6799 bioset_exit(&conf->bio_split);
95fc17aa 6800 kfree(conf->stripe_hashtbl);
aaf9f12e 6801 kfree(conf->pending_data);
95fc17aa
DW		 6802 kfree(conf);
6803}
6804
29c6d1bb 6805static int raid456_cpu_up_prepare(unsigned int cpu, struct hlist_node *node)
36d1c647 6806{
29c6d1bb 6807 struct r5conf *conf = hlist_entry_safe(node, struct r5conf, node);
36d1c647
DW		 6808 struct raid5_percpu *percpu = per_cpu_ptr(conf->percpu, cpu);
6809
29c6d1bb 6810 if (alloc_scratch_buffer(conf, percpu)) {
cc6167b4
N		 6811 pr_warn("%s: failed memory allocation for cpu%u\n",
6812 __func__, cpu);
29c6d1bb 6813 return -ENOMEM;
36d1c647 6814 }
29c6d1bb 6815 return 0;
36d1c647 6816}
36d1c647 6817
d1688a6d 6818static int raid5_alloc_percpu(struct r5conf *conf)
36d1c647 6819{
789b5e03 6820 int err = 0;
36d1c647 6821
789b5e03
ON		 6822 conf->percpu = alloc_percpu(struct raid5_percpu);
6823 if (!conf->percpu)
36d1c647 6824 return -ENOMEM;
789b5e03 6825
29c6d1bb 6826 err = cpuhp_state_add_instance(CPUHP_MD_RAID5_PREPARE, &conf->node);
27a353c0
SL		 6827 if (!err) {
6828 conf->scribble_disks = max(conf->raid_disks,
6829 conf->previous_raid_disks);
6830 conf->scribble_sectors = max(conf->chunk_sectors,
6831 conf->prev_chunk_sectors);
6832 }
36d1c647
DW		 6833 return err;
6834}
6835
edbe83ab
N		 6836static unsigned long raid5_cache_scan(struct shrinker *shrink,
6837 struct shrink_control *sc)
6838{
6839 struct r5conf *conf = container_of(shrink, struct r5conf, shrinker);
2d5b569b
N		 6840 unsigned long ret = SHRINK_STOP;
6841
6842 if (mutex_trylock(&conf->cache_size_mutex)) {
6843 ret= 0;
49895bcc
N		 6844 while (ret < sc->nr_to_scan &&
6845 conf->max_nr_stripes > conf->min_nr_stripes) {
2d5b569b
N		 6846 if (drop_one_stripe(conf) == 0) {
6847 ret = SHRINK_STOP;
6848 break;
6849 }
6850 ret++;
6851 }
6852 mutex_unlock(&conf->cache_size_mutex);
edbe83ab
N		 6853 }
6854 return ret;
6855}
6856
6857static unsigned long raid5_cache_count(struct shrinker *shrink,
6858 struct shrink_control *sc)
6859{
6860 struct r5conf *conf = container_of(shrink, struct r5conf, shrinker);
6861
6862 if (conf->max_nr_stripes < conf->min_nr_stripes)
6863 /* unlikely, but not impossible */
6864 return 0;
6865 return conf->max_nr_stripes - conf->min_nr_stripes;
6866}
6867
d1688a6d 6868static struct r5conf *setup_conf(struct mddev *mddev)
1da177e4 6869{
d1688a6d 6870 struct r5conf *conf;
5e5e3e78 6871 int raid_disk, memory, max_disks;
3cb03002 6872 struct md_rdev *rdev;
1da177e4 6873 struct disk_info *disk;
0232605d 6874 char pers_name[6];
566c09c5 6875 int i;
60aaf933 6876 int group_cnt, worker_cnt_per_group;
6877 struct r5worker_group *new_group;
afeee514 6878 int ret;
1da177e4 6879
91adb564
N		 6880 if (mddev->new_level != 5
6881 && mddev->new_level != 4
6882 && mddev->new_level != 6) {
cc6167b4
N		 6883 pr_warn("md/raid:%s: raid level not set to 4/5/6 (%d)\n",
6884 mdname(mddev), mddev->new_level);
91adb564 6885 return ERR_PTR(-EIO);
1da177e4 6886 }
91adb564
N		 6887 if ((mddev->new_level == 5
6888 && !algorithm_valid_raid5(mddev->new_layout)) ||
6889 (mddev->new_level == 6
6890 && !algorithm_valid_raid6(mddev->new_layout))) {
cc6167b4
N		 6891 pr_warn("md/raid:%s: layout %d not supported\n",
6892 mdname(mddev), mddev->new_layout);
91adb564 6893 return ERR_PTR(-EIO);
99c0fb5f 6894 }
91adb564 6895 if (mddev->new_level == 6 && mddev->raid_disks < 4) {
cc6167b4
N		 6896 pr_warn("md/raid:%s: not enough configured devices (%d, minimum 4)\n",
6897 mdname(mddev), mddev->raid_disks);
91adb564 6898 return ERR_PTR(-EINVAL);
4bbf3771
N		 6899 }
6900
664e7c41
AN		 6901 if (!mddev->new_chunk_sectors ||
6902 (mddev->new_chunk_sectors << 9) % PAGE_SIZE ||
6903 !is_power_of_2(mddev->new_chunk_sectors)) {
cc6167b4
N		 6904 pr_warn("md/raid:%s: invalid chunk size %d\n",
6905 mdname(mddev), mddev->new_chunk_sectors << 9);
91adb564 6906 return ERR_PTR(-EINVAL);
f6705578
N		 6907 }
6908
d1688a6d 6909 conf = kzalloc(sizeof(struct r5conf), GFP_KERNEL);
91adb564 6910 if (conf == NULL)
1da177e4 6911 goto abort;
aaf9f12e
SL		 6912 INIT_LIST_HEAD(&conf->free_list);
6913 INIT_LIST_HEAD(&conf->pending_list);
6396bb22
KC		 6914 conf->pending_data = kcalloc(PENDING_IO_MAX,
6915 sizeof(struct r5pending_data),
6916 GFP_KERNEL);
aaf9f12e
SL		 6917 if (!conf->pending_data)
6918 goto abort;
6919 for (i = 0; i < PENDING_IO_MAX; i++)
6920 list_add(&conf->pending_data[i].sibling, &conf->free_list);
851c30c9 6921 /* Don't enable multi-threading by default*/
60aaf933 6922 if (!alloc_thread_groups(conf, 0, &group_cnt, &worker_cnt_per_group,
6923 &new_group)) {
6924 conf->group_cnt = group_cnt;
6925 conf->worker_cnt_per_group = worker_cnt_per_group;
6926 conf->worker_groups = new_group;
6927 } else
851c30c9 6928 goto abort;
f5efd45a 6929 spin_lock_init(&conf->device_lock);
c46501b2 6930 seqcount_init(&conf->gen_lock);
2d5b569b 6931 mutex_init(&conf->cache_size_mutex);
b1b46486 6932 init_waitqueue_head(&conf->wait_for_quiescent);
6ab2a4b8 6933 init_waitqueue_head(&conf->wait_for_stripe);
f5efd45a
DW		 6934 init_waitqueue_head(&conf->wait_for_overlap);
6935 INIT_LIST_HEAD(&conf->handle_list);
535ae4eb 6936 INIT_LIST_HEAD(&conf->loprio_list);
f5efd45a
DW		 6937 INIT_LIST_HEAD(&conf->hold_list);
6938 INIT_LIST_HEAD(&conf->delayed_list);
6939 INIT_LIST_HEAD(&conf->bitmap_list);
773ca82f 6940 init_llist_head(&conf->released_stripes);
f5efd45a
DW		 6941 atomic_set(&conf->active_stripes, 0);
6942 atomic_set(&conf->preread_active_stripes, 0);
6943 atomic_set(&conf->active_aligned_reads, 0);
765d704d
SL		 6944 spin_lock_init(&conf->pending_bios_lock);
6945 conf->batch_bio_dispatch = true;
6946 rdev_for_each(rdev, mddev) {
6947 if (test_bit(Journal, &rdev->flags))
6948 continue;
6949 if (blk_queue_nonrot(bdev_get_queue(rdev->bdev))) {
6950 conf->batch_bio_dispatch = false;
6951 break;
6952 }
6953 }
6954
f5efd45a 6955 conf->bypass_threshold = BYPASS_THRESHOLD;
d890fa2b 6956 conf->recovery_disabled = mddev->recovery_disabled - 1;
91adb564
N		 6957
6958 conf->raid_disks = mddev->raid_disks;
6959 if (mddev->reshape_position == MaxSector)
6960 conf->previous_raid_disks = mddev->raid_disks;
6961 else
f6705578 6962 conf->previous_raid_disks = mddev->raid_disks - mddev->delta_disks;
5e5e3e78 6963 max_disks = max(conf->raid_disks, conf->previous_raid_disks);
f6705578 6964
6396bb22 6965 conf->disks = kcalloc(max_disks, sizeof(struct disk_info),
b55e6bfc 6966 GFP_KERNEL);
d7bd398e 6967
b55e6bfc
N		 6968 if (!conf->disks)
6969 goto abort;
9ffae0cf 6970
d7bd398e
SL		 6971 for (i = 0; i < max_disks; i++) {
6972 conf->disks[i].extra_page = alloc_page(GFP_KERNEL);
6973 if (!conf->disks[i].extra_page)
6974 goto abort;
6975 }
6976
afeee514
KO		 6977 ret = bioset_init(&conf->bio_split, BIO_POOL_SIZE, 0, 0);
6978 if (ret)
dd7a8f5d 6979 goto abort;
1da177e4
LT		 6980 conf->mddev = mddev;
6981
fccddba0 6982 if ((conf->stripe_hashtbl = kzalloc(PAGE_SIZE, GFP_KERNEL)) == NULL)
1da177e4 6983 goto abort;
1da177e4 6984
566c09c5
SL		 6985 /* We init hash_locks[0] separately to that it can be used
6986 * as the reference lock in the spin_lock_nest_lock() call
6987 * in lock_all_device_hash_locks_irq in order to convince
6988 * lockdep that we know what we are doing.
6989 */
6990 spin_lock_init(conf->hash_locks);
6991 for (i = 1; i < NR_STRIPE_HASH_LOCKS; i++)
6992 spin_lock_init(conf->hash_locks + i);
6993
6994 for (i = 0; i < NR_STRIPE_HASH_LOCKS; i++)
6995 INIT_LIST_HEAD(conf->inactive_list + i);
6996
6997 for (i = 0; i < NR_STRIPE_HASH_LOCKS; i++)
6998 INIT_LIST_HEAD(conf->temp_inactive_list + i);
6999
1e6d690b
SL		 7000 atomic_set(&conf->r5c_cached_full_stripes, 0);
7001 INIT_LIST_HEAD(&conf->r5c_full_stripe_list);
7002 atomic_set(&conf->r5c_cached_partial_stripes, 0);
7003 INIT_LIST_HEAD(&conf->r5c_partial_stripe_list);
e33fbb9c
SL		 7004 atomic_set(&conf->r5c_flushing_full_stripes, 0);
7005 atomic_set(&conf->r5c_flushing_partial_stripes, 0);
1e6d690b 7006
36d1c647 7007 conf->level = mddev->new_level;
46d5b785 7008 conf->chunk_sectors = mddev->new_chunk_sectors;
36d1c647
DW		 7009 if (raid5_alloc_percpu(conf) != 0)
7010 goto abort;
7011
0c55e022 7012 pr_debug("raid456: run(%s) called.\n", mdname(mddev));
1da177e4 7013
dafb20fa 7014 rdev_for_each(rdev, mddev) {
1da177e4 7015 raid_disk = rdev->raid_disk;
5e5e3e78 7016 if (raid_disk >= max_disks
f2076e7d 7017 || raid_disk < 0 || test_bit(Journal, &rdev->flags))
1da177e4
LT		 7018 continue;
7019 disk = conf->disks + raid_disk;
7020
17045f52
N		 7021 if (test_bit(Replacement, &rdev->flags)) {
7022 if (disk->replacement)
7023 goto abort;
7024 disk->replacement = rdev;
7025 } else {
7026 if (disk->rdev)
7027 goto abort;
7028 disk->rdev = rdev;
7029 }
1da177e4 7030
b2d444d7 7031 if (test_bit(In_sync, &rdev->flags)) {
1da177e4 7032 char b[BDEVNAME_SIZE];
cc6167b4
N		 7033 pr_info("md/raid:%s: device %s operational as raid disk %d\n",
7034 mdname(mddev), bdevname(rdev->bdev, b), raid_disk);
d6b212f4 7035 } else if (rdev->saved_raid_disk != raid_disk)
8c2e870a
NB		 7036 /* Cannot rely on bitmap to complete recovery */
7037 conf->fullsync = 1;
1da177e4
LT		 7038 }
7039
91adb564 7040 conf->level = mddev->new_level;
584acdd4 7041 if (conf->level == 6) {
16a53ecc 7042 conf->max_degraded = 2;
584acdd4
MS		 7043 if (raid6_call.xor_syndrome)
7044 conf->rmw_level = PARITY_ENABLE_RMW;
7045 else
7046 conf->rmw_level = PARITY_DISABLE_RMW;
7047 } else {
16a53ecc 7048 conf->max_degraded = 1;
584acdd4
MS		 7049 conf->rmw_level = PARITY_ENABLE_RMW;
7050 }
91adb564 7051 conf->algorithm = mddev->new_layout;
fef9c61f 7052 conf->reshape_progress = mddev->reshape_position;
e183eaed 7053 if (conf->reshape_progress != MaxSector) {
09c9e5fa 7054 conf->prev_chunk_sectors = mddev->chunk_sectors;
e183eaed 7055 conf->prev_algo = mddev->layout;
5cac6bcb
N		 7056 } else {
7057 conf->prev_chunk_sectors = conf->chunk_sectors;
7058 conf->prev_algo = conf->algorithm;
e183eaed 7059 }
1da177e4 7060
edbe83ab 7061 conf->min_nr_stripes = NR_STRIPES;
ad5b0f76
SL		 7062 if (mddev->reshape_position != MaxSector) {
7063 int stripes = max_t(int,
7064 ((mddev->chunk_sectors << 9) / STRIPE_SIZE) * 4,
7065 ((mddev->new_chunk_sectors << 9) / STRIPE_SIZE) * 4);
7066 conf->min_nr_stripes = max(NR_STRIPES, stripes);
7067 if (conf->min_nr_stripes != NR_STRIPES)
cc6167b4 7068 pr_info("md/raid:%s: force stripe size %d for reshape\n",
ad5b0f76
SL		 7069 mdname(mddev), conf->min_nr_stripes);
7070 }
edbe83ab 7071 memory = conf->min_nr_stripes * (sizeof(struct stripe_head) +
5e5e3e78 7072 max_disks * ((sizeof(struct bio) + PAGE_SIZE))) / 1024;
4bda556a 7073 atomic_set(&conf->empty_inactive_list_nr, NR_STRIPE_HASH_LOCKS);
edbe83ab 7074 if (grow_stripes(conf, conf->min_nr_stripes)) {
cc6167b4
N		 7075 pr_warn("md/raid:%s: couldn't allocate %dkB for buffers\n",
7076 mdname(mddev), memory);
91adb564
N		 7077 goto abort;
7078 } else
cc6167b4 7079 pr_debug("md/raid:%s: allocated %dkB\n", mdname(mddev), memory);
edbe83ab
N		 7080 /*
7081 * Losing a stripe head costs more than the time to refill it,
7082 * it reduces the queue depth and so can hurt throughput.
7083 * So set it rather large, scaled by number of devices.
7084 */
7085 conf->shrinker.seeks = DEFAULT_SEEKS * conf->raid_disks * 4;
7086 conf->shrinker.scan_objects = raid5_cache_scan;
7087 conf->shrinker.count_objects = raid5_cache_count;
7088 conf->shrinker.batch = 128;
7089 conf->shrinker.flags = 0;
6a0f53ff 7090 if (register_shrinker(&conf->shrinker)) {
cc6167b4
N		 7091 pr_warn("md/raid:%s: couldn't register shrinker.\n",
7092 mdname(mddev));
6a0f53ff
CY		 7093 goto abort;
7094 }
1da177e4 7095
0232605d
N		 7096 sprintf(pers_name, "raid%d", mddev->new_level);
7097 conf->thread = md_register_thread(raid5d, mddev, pers_name);
91adb564 7098 if (!conf->thread) {
cc6167b4
N		 7099 pr_warn("md/raid:%s: couldn't allocate thread.\n",
7100 mdname(mddev));
16a53ecc
N		 7101 goto abort;
7102 }
91adb564
N		 7103
7104 return conf;
7105
7106 abort:
7107 if (conf) {
95fc17aa 7108 free_conf(conf);
91adb564
N		 7109 return ERR_PTR(-EIO);
7110 } else
7111 return ERR_PTR(-ENOMEM);
7112}
7113
c148ffdc
N		 7114static int only_parity(int raid_disk, int algo, int raid_disks, int max_degraded)
7115{
7116 switch (algo) {
7117 case ALGORITHM_PARITY_0:
7118 if (raid_disk < max_degraded)
7119 return 1;
7120 break;
7121 case ALGORITHM_PARITY_N:
7122 if (raid_disk >= raid_disks - max_degraded)
7123 return 1;
7124 break;
7125 case ALGORITHM_PARITY_0_6:
f72ffdd6 7126 if (raid_disk == 0 ||
c148ffdc
N		 7127 raid_disk == raid_disks - 1)
7128 return 1;
7129 break;
7130 case ALGORITHM_LEFT_ASYMMETRIC_6:
7131 case ALGORITHM_RIGHT_ASYMMETRIC_6:
7132 case ALGORITHM_LEFT_SYMMETRIC_6:
7133 case ALGORITHM_RIGHT_SYMMETRIC_6:
7134 if (raid_disk == raid_disks - 1)
7135 return 1;
7136 }
7137 return 0;
7138}
7139
849674e4 7140static int raid5_run(struct mddev *mddev)
91adb564 7141{
d1688a6d 7142 struct r5conf *conf;
9f7c2220 7143 int working_disks = 0;
c148ffdc 7144 int dirty_parity_disks = 0;
3cb03002 7145 struct md_rdev *rdev;
713cf5a6 7146 struct md_rdev *journal_dev = NULL;
c148ffdc 7147 sector_t reshape_offset = 0;
17045f52 7148 int i;
b5254dd5
N		 7149 long long min_offset_diff = 0;
7150 int first = 1;
91adb564 7151
a415c0f1
N		 7152 if (mddev_init_writes_pending(mddev) < 0)
7153 return -ENOMEM;
7154
8c6ac868 7155 if (mddev->recovery_cp != MaxSector)
cc6167b4
N		 7156 pr_notice("md/raid:%s: not clean -- starting background reconstruction\n",
7157 mdname(mddev));
b5254dd5
N		 7158
7159 rdev_for_each(rdev, mddev) {
7160 long long diff;
713cf5a6 7161
f2076e7d 7162 if (test_bit(Journal, &rdev->flags)) {
713cf5a6 7163 journal_dev = rdev;
f2076e7d
SL		 7164 continue;
7165 }
b5254dd5
N		 7166 if (rdev->raid_disk < 0)
7167 continue;
7168 diff = (rdev->new_data_offset - rdev->data_offset);
7169 if (first) {
7170 min_offset_diff = diff;
7171 first = 0;
7172 } else if (mddev->reshape_backwards &&
7173 diff < min_offset_diff)
7174 min_offset_diff = diff;
7175 else if (!mddev->reshape_backwards &&
7176 diff > min_offset_diff)
7177 min_offset_diff = diff;
7178 }
7179
230b55fa
N		 7180 if ((test_bit(MD_HAS_JOURNAL, &mddev->flags) || journal_dev) &&
7181 (mddev->bitmap_info.offset || mddev->bitmap_info.file)) {
7182 pr_notice("md/raid:%s: array cannot have both journal and bitmap\n",
7183 mdname(mddev));
7184 return -EINVAL;
7185 }
7186
91adb564
N		 7187 if (mddev->reshape_position != MaxSector) {
7188 /* Check that we can continue the reshape.
b5254dd5
N		 7189 * Difficulties arise if the stripe we would write to
7190 * next is at or after the stripe we would read from next.
7191 * For a reshape that changes the number of devices, this
7192 * is only possible for a very short time, and mdadm makes
7193 * sure that time appears to have past before assembling
7194 * the array. So we fail if that time hasn't passed.
7195 * For a reshape that keeps the number of devices the same
7196 * mdadm must be monitoring the reshape can keeping the
7197 * critical areas read-only and backed up. It will start
7198 * the array in read-only mode, so we check for that.
91adb564
N		 7199 */
7200 sector_t here_new, here_old;
7201 int old_disks;
18b00334 7202 int max_degraded = (mddev->level == 6 ? 2 : 1);
05256d98
N		 7203 int chunk_sectors;
7204 int new_data_disks;
91adb564 7205
713cf5a6 7206 if (journal_dev) {
cc6167b4
N		 7207 pr_warn("md/raid:%s: don't support reshape with journal - aborting.\n",
7208 mdname(mddev));
713cf5a6
SL		 7209 return -EINVAL;
7210 }
7211
88ce4930 7212 if (mddev->new_level != mddev->level) {
cc6167b4
N		 7213 pr_warn("md/raid:%s: unsupported reshape required - aborting.\n",
7214 mdname(mddev));
91adb564
N		 7215 return -EINVAL;
7216 }
91adb564
N		 7217 old_disks = mddev->raid_disks - mddev->delta_disks;
7218 /* reshape_position must be on a new-stripe boundary, and one
7219 * further up in new geometry must map after here in old
7220 * geometry.
05256d98
N		 7221 * If the chunk sizes are different, then as we perform reshape
7222 * in units of the largest of the two, reshape_position needs
7223 * be a multiple of the largest chunk size times new data disks.
91adb564
N		 7224 */
7225 here_new = mddev->reshape_position;
05256d98
N		 7226 chunk_sectors = max(mddev->chunk_sectors, mddev->new_chunk_sectors);
7227 new_data_disks = mddev->raid_disks - max_degraded;
7228 if (sector_div(here_new, chunk_sectors * new_data_disks)) {
cc6167b4
N		 7229 pr_warn("md/raid:%s: reshape_position not on a stripe boundary\n",
7230 mdname(mddev));
91adb564
N		 7231 return -EINVAL;
7232 }
05256d98 7233 reshape_offset = here_new * chunk_sectors;
91adb564
N		 7234 /* here_new is the stripe we will write to */
7235 here_old = mddev->reshape_position;
05256d98 7236 sector_div(here_old, chunk_sectors * (old_disks-max_degraded));
91adb564
N		 7237 /* here_old is the first stripe that we might need to read
7238 * from */
67ac6011
N		 7239 if (mddev->delta_disks == 0) {
7240 /* We cannot be sure it is safe to start an in-place
b5254dd5 7241 * reshape. It is only safe if user-space is monitoring
67ac6011
N		 7242 * and taking constant backups.
7243 * mdadm always starts a situation like this in
7244 * readonly mode so it can take control before
7245 * allowing any writes. So just check for that.
7246 */
b5254dd5
N		 7247 if (abs(min_offset_diff) >= mddev->chunk_sectors &&
7248 abs(min_offset_diff) >= mddev->new_chunk_sectors)
7249 /* not really in-place - so OK */;
7250 else if (mddev->ro == 0) {
cc6167b4
N		 7251 pr_warn("md/raid:%s: in-place reshape must be started in read-only mode - aborting\n",
7252 mdname(mddev));
67ac6011
N		 7253 return -EINVAL;
7254 }
2c810cdd 7255 } else if (mddev->reshape_backwards
05256d98
N		 7256 ? (here_new * chunk_sectors + min_offset_diff <=
7257 here_old * chunk_sectors)
7258 : (here_new * chunk_sectors >=
7259 here_old * chunk_sectors + (-min_offset_diff))) {
91adb564 7260 /* Reading from the same stripe as writing to - bad */
cc6167b4
N		 7261 pr_warn("md/raid:%s: reshape_position too early for auto-recovery - aborting.\n",
7262 mdname(mddev));
91adb564
N		 7263 return -EINVAL;
7264 }
cc6167b4 7265 pr_debug("md/raid:%s: reshape will continue\n", mdname(mddev));
91adb564
N		 7266 /* OK, we should be able to continue; */
7267 } else {
7268 BUG_ON(mddev->level != mddev->new_level);
7269 BUG_ON(mddev->layout != mddev->new_layout);
664e7c41 7270 BUG_ON(mddev->chunk_sectors != mddev->new_chunk_sectors);
91adb564 7271 BUG_ON(mddev->delta_disks != 0);
1da177e4 7272 }
91adb564 7273
3418d036
AP		 7274 if (test_bit(MD_HAS_JOURNAL, &mddev->flags) &&
7275 test_bit(MD_HAS_PPL, &mddev->flags)) {
7276 pr_warn("md/raid:%s: using journal device and PPL not allowed - disabling PPL\n",
7277 mdname(mddev));
7278 clear_bit(MD_HAS_PPL, &mddev->flags);
ddc08823 7279 clear_bit(MD_HAS_MULTIPLE_PPLS, &mddev->flags);
3418d036
AP		 7280 }
7281
245f46c2
N		 7282 if (mddev->private == NULL)
7283 conf = setup_conf(mddev);
7284 else
7285 conf = mddev->private;
7286
91adb564
N		 7287 if (IS_ERR(conf))
7288 return PTR_ERR(conf);
7289
486b0f7b
SL		 7290 if (test_bit(MD_HAS_JOURNAL, &mddev->flags)) {
7291 if (!journal_dev) {
cc6167b4
N		 7292 pr_warn("md/raid:%s: journal disk is missing, force array readonly\n",
7293 mdname(mddev));
486b0f7b
SL		 7294 mddev->ro = 1;
7295 set_disk_ro(mddev->gendisk, 1);
7296 } else if (mddev->recovery_cp == MaxSector)
7297 set_bit(MD_JOURNAL_CLEAN, &mddev->flags);
7dde2ad3
SL		 7298 }
7299
b5254dd5 7300 conf->min_offset_diff = min_offset_diff;
91adb564
N		 7301 mddev->thread = conf->thread;
7302 conf->thread = NULL;
7303 mddev->private = conf;
7304
17045f52
N		 7305 for (i = 0; i < conf->raid_disks && conf->previous_raid_disks;
7306 i++) {
7307 rdev = conf->disks[i].rdev;
7308 if (!rdev && conf->disks[i].replacement) {
7309 /* The replacement is all we have yet */
7310 rdev = conf->disks[i].replacement;
7311 conf->disks[i].replacement = NULL;
7312 clear_bit(Replacement, &rdev->flags);
7313 conf->disks[i].rdev = rdev;
7314 }
7315 if (!rdev)
c148ffdc 7316 continue;
17045f52
N		 7317 if (conf->disks[i].replacement &&
7318 conf->reshape_progress != MaxSector) {
7319 /* replacements and reshape simply do not mix. */
cc6167b4 7320 pr_warn("md: cannot handle concurrent replacement and reshape.\n");
17045f52
N		 7321 goto abort;
7322 }
2f115882 7323 if (test_bit(In_sync, &rdev->flags)) {
91adb564 7324 working_disks++;
2f115882
N		 7325 continue;
7326 }
c148ffdc
N		 7327 /* This disc is not fully in-sync. However if it
7328 * just stored parity (beyond the recovery_offset),
7329 * when we don't need to be concerned about the
7330 * array being dirty.
7331 * When reshape goes 'backwards', we never have
7332 * partially completed devices, so we only need
7333 * to worry about reshape going forwards.
7334 */
7335 /* Hack because v0.91 doesn't store recovery_offset properly. */
7336 if (mddev->major_version == 0 &&
7337 mddev->minor_version > 90)
7338 rdev->recovery_offset = reshape_offset;
5026d7a9 7339
c148ffdc
N		 7340 if (rdev->recovery_offset < reshape_offset) {
7341 /* We need to check old and new layout */
7342 if (!only_parity(rdev->raid_disk,
7343 conf->algorithm,
7344 conf->raid_disks,
7345 conf->max_degraded))
7346 continue;
7347 }
7348 if (!only_parity(rdev->raid_disk,
7349 conf->prev_algo,
7350 conf->previous_raid_disks,
7351 conf->max_degraded))
7352 continue;
7353 dirty_parity_disks++;
7354 }
91adb564 7355
17045f52
N		 7356 /*
7357 * 0 for a fully functional array, 1 or 2 for a degraded array.
7358 */
2e38a37f 7359 mddev->degraded = raid5_calc_degraded(conf);
91adb564 7360
674806d6 7361 if (has_failed(conf)) {
cc6167b4 7362 pr_crit("md/raid:%s: not enough operational devices (%d/%d failed)\n",
02c2de8c 7363 mdname(mddev), mddev->degraded, conf->raid_disks);
1da177e4
LT		 7364 goto abort;
7365 }
7366
91adb564 7367 /* device size must be a multiple of chunk size */
9d8f0363 7368 mddev->dev_sectors &= ~(mddev->chunk_sectors - 1);
91adb564
N		 7369 mddev->resync_max_sectors = mddev->dev_sectors;
7370
c148ffdc 7371 if (mddev->degraded > dirty_parity_disks &&
1da177e4 7372 mddev->recovery_cp != MaxSector) {
4536bf9b
AP		 7373 if (test_bit(MD_HAS_PPL, &mddev->flags))
7374 pr_crit("md/raid:%s: starting dirty degraded array with PPL.\n",
7375 mdname(mddev));
7376 else if (mddev->ok_start_degraded)
cc6167b4
N		 7377 pr_crit("md/raid:%s: starting dirty degraded array - data corruption possible.\n",
7378 mdname(mddev));
6ff8d8ec 7379 else {
cc6167b4
N		 7380 pr_crit("md/raid:%s: cannot start dirty degraded array.\n",
7381 mdname(mddev));
6ff8d8ec
N		 7382 goto abort;
7383 }
1da177e4
LT		 7384 }
7385
cc6167b4
N		 7386 pr_info("md/raid:%s: raid level %d active with %d out of %d devices, algorithm %d\n",
7387 mdname(mddev), conf->level,
7388 mddev->raid_disks-mddev->degraded, mddev->raid_disks,
7389 mddev->new_layout);
1da177e4
LT		 7390
7391 print_raid5_conf(conf);
7392
fef9c61f 7393 if (conf->reshape_progress != MaxSector) {
fef9c61f 7394 conf->reshape_safe = conf->reshape_progress;
f6705578
N		 7395 atomic_set(&conf->reshape_stripes, 0);
7396 clear_bit(MD_RECOVERY_SYNC, &mddev->recovery);
7397 clear_bit(MD_RECOVERY_CHECK, &mddev->recovery);
7398 set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery);
7399 set_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
7400 mddev->sync_thread = md_register_thread(md_do_sync, mddev,
0da3c619 7401 "reshape");
e406f12d
AP		 7402 if (!mddev->sync_thread)
7403 goto abort;
f6705578
N		 7404 }
7405
1da177e4 7406 /* Ok, everything is just fine now */
a64c876f
N		 7407 if (mddev->to_remove == &raid5_attrs_group)
7408 mddev->to_remove = NULL;
00bcb4ac
N		 7409 else if (mddev->kobj.sd &&
7410 sysfs_create_group(&mddev->kobj, &raid5_attrs_group))
cc6167b4
N		 7411 pr_warn("raid5: failed to create sysfs attributes for %s\n",
7412 mdname(mddev));
4a5add49 7413 md_set_array_sectors(mddev, raid5_size(mddev, 0, 0));
7a5febe9 7414
4a5add49 7415 if (mddev->queue) {
9f7c2220 7416 int chunk_size;
4a5add49
N		 7417 /* read-ahead size must cover two whole stripes, which
7418 * is 2 * (datadisks) * chunksize where 'n' is the
7419 * number of raid devices
7420 */
7421 int data_disks = conf->previous_raid_disks - conf->max_degraded;
7422 int stripe = data_disks *
7423 ((mddev->chunk_sectors << 9) / PAGE_SIZE);
dc3b17cc
JK		 7424 if (mddev->queue->backing_dev_info->ra_pages < 2 * stripe)
7425 mddev->queue->backing_dev_info->ra_pages = 2 * stripe;
91adb564 7426
9f7c2220
N		 7427 chunk_size = mddev->chunk_sectors << 9;
7428 blk_queue_io_min(mddev->queue, chunk_size);
7429 blk_queue_io_opt(mddev->queue, chunk_size *
7430 (conf->raid_disks - conf->max_degraded));
c78afc62 7431 mddev->queue->limits.raid_partial_stripes_expensive = 1;
620125f2
SL		 7432 /*
7433 * We can only discard a whole stripe. It doesn't make sense to
7434 * discard data disk but write parity disk
7435 */
7436 stripe = stripe * PAGE_SIZE;
4ac6875e
N		 7437 /* Round up to power of 2, as discard handling
7438 * currently assumes that */
7439 while ((stripe-1) & stripe)
7440 stripe = (stripe | (stripe-1)) + 1;
620125f2
SL		 7441 mddev->queue->limits.discard_alignment = stripe;
7442 mddev->queue->limits.discard_granularity = stripe;
e8d7c332 7443
5026d7a9 7444 blk_queue_max_write_same_sectors(mddev->queue, 0);
3deff1a7 7445 blk_queue_max_write_zeroes_sectors(mddev->queue, 0);
5026d7a9 7446
05616be5 7447 rdev_for_each(rdev, mddev) {
9f7c2220
N		 7448 disk_stack_limits(mddev->gendisk, rdev->bdev,
7449 rdev->data_offset << 9);
05616be5
N		 7450 disk_stack_limits(mddev->gendisk, rdev->bdev,
7451 rdev->new_data_offset << 9);
7452 }
620125f2 7453
48920ff2
CH		 7454 /*
7455 * zeroing is required, otherwise data
7456 * could be lost. Consider a scenario: discard a stripe
7457 * (the stripe could be inconsistent if
7458 * discard_zeroes_data is 0); write one disk of the
7459 * stripe (the stripe could be inconsistent again
7460 * depending on which disks are used to calculate
7461 * parity); the disk is broken; The stripe data of this
7462 * disk is lost.
7463 *
7464 * We only allow DISCARD if the sysadmin has confirmed that
7465 * only safe devices are in use by setting a module parameter.
7466 * A better idea might be to turn DISCARD into WRITE_ZEROES
7467 * requests, as that is required to be safe.
7468 */
7469 if (devices_handle_discard_safely &&
e7597e69
JS		 7470 mddev->queue->limits.max_discard_sectors >= (stripe >> 9) &&
7471 mddev->queue->limits.discard_granularity >= stripe)
8b904b5b 7472 blk_queue_flag_set(QUEUE_FLAG_DISCARD,
620125f2
SL		 7473 mddev->queue);
7474 else
8b904b5b 7475 blk_queue_flag_clear(QUEUE_FLAG_DISCARD,
620125f2 7476 mddev->queue);
1dffdddd
SL		 7477
7478 blk_queue_max_hw_sectors(mddev->queue, UINT_MAX);
9f7c2220 7479 }
23032a0e 7480
845b9e22 7481 if (log_init(conf, journal_dev, raid5_has_ppl(conf)))
ff875738 7482 goto abort;
5c7e81c3 7483
1da177e4
LT		 7484 return 0;
7485abort:
01f96c0a 7486 md_unregister_thread(&mddev->thread);
e4f869d9
N		 7487 print_raid5_conf(conf);
7488 free_conf(conf);
1da177e4 7489 mddev->private = NULL;
cc6167b4 7490 pr_warn("md/raid:%s: failed to run raid set.\n", mdname(mddev));
1da177e4
LT		 7491 return -EIO;
7492}
7493
afa0f557 7494static void raid5_free(struct mddev *mddev, void *priv)
1da177e4 7495{
afa0f557 7496 struct r5conf *conf = priv;
1da177e4 7497
95fc17aa 7498 free_conf(conf);
a64c876f 7499 mddev->to_remove = &raid5_attrs_group;
1da177e4
LT		 7500}
7501
849674e4 7502static void raid5_status(struct seq_file *seq, struct mddev *mddev)
1da177e4 7503{
d1688a6d 7504 struct r5conf *conf = mddev->private;
1da177e4
LT		 7505 int i;
7506
9d8f0363 7507 seq_printf(seq, " level %d, %dk chunk, algorithm %d", mddev->level,
3cb5edf4 7508 conf->chunk_sectors / 2, mddev->layout);
02c2de8c 7509 seq_printf (seq, " [%d/%d] [", conf->raid_disks, conf->raid_disks - mddev->degraded);
5fd13351
N		 7510 rcu_read_lock();
7511 for (i = 0; i < conf->raid_disks; i++) {
7512 struct md_rdev *rdev = rcu_dereference(conf->disks[i].rdev);
7513 seq_printf (seq, "%s", rdev && test_bit(In_sync, &rdev->flags) ? "U" : "_");
7514 }
7515 rcu_read_unlock();
1da177e4 7516 seq_printf (seq, "]");
1da177e4
LT		 7517}
7518
d1688a6d 7519static void print_raid5_conf (struct r5conf *conf)
1da177e4
LT		 7520{
7521 int i;
7522 struct disk_info *tmp;
7523
cc6167b4 7524 pr_debug("RAID conf printout:\n");
1da177e4 7525 if (!conf) {
cc6167b4 7526 pr_debug("(conf==NULL)\n");
1da177e4
LT		 7527 return;
7528 }
cc6167b4 7529 pr_debug(" --- level:%d rd:%d wd:%d\n", conf->level,
0c55e022
N		 7530 conf->raid_disks,
7531 conf->raid_disks - conf->mddev->degraded);
1da177e4
LT		 7532
7533 for (i = 0; i < conf->raid_disks; i++) {
7534 char b[BDEVNAME_SIZE];
7535 tmp = conf->disks + i;
7536 if (tmp->rdev)
cc6167b4 7537 pr_debug(" disk %d, o:%d, dev:%s\n",
0c55e022
N		 7538 i, !test_bit(Faulty, &tmp->rdev->flags),
7539 bdevname(tmp->rdev->bdev, b));
1da177e4
LT		 7540 }
7541}
7542
fd01b88c 7543static int raid5_spare_active(struct mddev *mddev)
1da177e4
LT		 7544{
7545 int i;
d1688a6d 7546 struct r5conf *conf = mddev->private;
1da177e4 7547 struct disk_info *tmp;
6b965620
N		 7548 int count = 0;
7549 unsigned long flags;
1da177e4
LT		 7550
7551 for (i = 0; i < conf->raid_disks; i++) {
7552 tmp = conf->disks + i;
dd054fce
N		 7553 if (tmp->replacement
7554 && tmp->replacement->recovery_offset == MaxSector
7555 && !test_bit(Faulty, &tmp->replacement->flags)
7556 && !test_and_set_bit(In_sync, &tmp->replacement->flags)) {
7557 /* Replacement has just become active. */
7558 if (!tmp->rdev
7559 || !test_and_clear_bit(In_sync, &tmp->rdev->flags))
7560 count++;
7561 if (tmp->rdev) {
7562 /* Replaced device not technically faulty,
7563 * but we need to be sure it gets removed
7564 * and never re-added.
7565 */
7566 set_bit(Faulty, &tmp->rdev->flags);
7567 sysfs_notify_dirent_safe(
7568 tmp->rdev->sysfs_state);
7569 }
7570 sysfs_notify_dirent_safe(tmp->replacement->sysfs_state);
7571 } else if (tmp->rdev
70fffd0b 7572 && tmp->rdev->recovery_offset == MaxSector
b2d444d7 7573 && !test_bit(Faulty, &tmp->rdev->flags)
c04be0aa 7574 && !test_and_set_bit(In_sync, &tmp->rdev->flags)) {
6b965620 7575 count++;
43c73ca4 7576 sysfs_notify_dirent_safe(tmp->rdev->sysfs_state);
1da177e4
LT		 7577 }
7578 }
6b965620 7579 spin_lock_irqsave(&conf->device_lock, flags);
2e38a37f 7580 mddev->degraded = raid5_calc_degraded(conf);
6b965620 7581 spin_unlock_irqrestore(&conf->device_lock, flags);
1da177e4 7582 print_raid5_conf(conf);
6b965620 7583 return count;
1da177e4
LT		 7584}
7585
b8321b68 7586static int raid5_remove_disk(struct mddev *mddev, struct md_rdev *rdev)
1da177e4 7587{
d1688a6d 7588 struct r5conf *conf = mddev->private;
1da177e4 7589 int err = 0;
b8321b68 7590 int number = rdev->raid_disk;
657e3e4d 7591 struct md_rdev **rdevp;
1da177e4
LT		 7592 struct disk_info *p = conf->disks + number;
7593
7594 print_raid5_conf(conf);
f6b6ec5c 7595 if (test_bit(Journal, &rdev->flags) && conf->log) {
c2bb6242 7596 /*
f6b6ec5c
SL		 7597 * we can't wait pending write here, as this is called in
7598 * raid5d, wait will deadlock.
84dd97a6
N		 7599 * neilb: there is no locking about new writes here,
7600 * so this cannot be safe.
c2bb6242 7601 */
70d466f7
SL		 7602 if (atomic_read(&conf->active_stripes) ||
7603 atomic_read(&conf->r5c_cached_full_stripes) ||
7604 atomic_read(&conf->r5c_cached_partial_stripes)) {
f6b6ec5c 7605 return -EBUSY;
84dd97a6 7606 }
ff875738 7607 log_exit(conf);
f6b6ec5c 7608 return 0;
c2bb6242 7609 }
657e3e4d
N		 7610 if (rdev == p->rdev)
7611 rdevp = &p->rdev;
7612 else if (rdev == p->replacement)
7613 rdevp = &p->replacement;
7614 else
7615 return 0;
7616
7617 if (number >= conf->raid_disks &&
7618 conf->reshape_progress == MaxSector)
7619 clear_bit(In_sync, &rdev->flags);
7620
7621 if (test_bit(In_sync, &rdev->flags) ||
7622 atomic_read(&rdev->nr_pending)) {
7623 err = -EBUSY;
7624 goto abort;
7625 }
7626 /* Only remove non-faulty devices if recovery
7627 * isn't possible.
7628 */
7629 if (!test_bit(Faulty, &rdev->flags) &&
7630 mddev->recovery_disabled != conf->recovery_disabled &&
7631 !has_failed(conf) &&
dd054fce 7632 (!p->replacement || p->replacement == rdev) &&
657e3e4d
N		 7633 number < conf->raid_disks) {
7634 err = -EBUSY;
7635 goto abort;
7636 }
7637 *rdevp = NULL;
d787be40
N		 7638 if (!test_bit(RemoveSynchronized, &rdev->flags)) {
7639 synchronize_rcu();
7640 if (atomic_read(&rdev->nr_pending)) {
7641 /* lost the race, try later */
7642 err = -EBUSY;
7643 *rdevp = rdev;
7644 }
7645 }
6358c239
AP		 7646 if (!err) {
7647 err = log_modify(conf, rdev, false);
7648 if (err)
7649 goto abort;
7650 }
d787be40 7651 if (p->replacement) {
dd054fce
N		 7652 /* We must have just cleared 'rdev' */
7653 p->rdev = p->replacement;
7654 clear_bit(Replacement, &p->replacement->flags);
7655 smp_mb(); /* Make sure other CPUs may see both as identical
7656 * but will never see neither - if they are careful
7657 */
7658 p->replacement = NULL;
6358c239
AP		 7659
7660 if (!err)
7661 err = log_modify(conf, p->rdev, true);
e5bc9c3c
GJ		 7662 }
7663
7664 clear_bit(WantReplacement, &rdev->flags);
1da177e4
LT		 7665abort:
7666
7667 print_raid5_conf(conf);
7668 return err;
7669}
7670
fd01b88c 7671static int raid5_add_disk(struct mddev *mddev, struct md_rdev *rdev)
1da177e4 7672{
d1688a6d 7673 struct r5conf *conf = mddev->private;
d9771f5e 7674 int ret, err = -EEXIST;
1da177e4
LT		 7675 int disk;
7676 struct disk_info *p;
6c2fce2e
NB		 7677 int first = 0;
7678 int last = conf->raid_disks - 1;
1da177e4 7679
f6b6ec5c 7680 if (test_bit(Journal, &rdev->flags)) {
f6b6ec5c
SL		 7681 if (conf->log)
7682 return -EBUSY;
7683
7684 rdev->raid_disk = 0;
7685 /*
7686 * The array is in readonly mode if journal is missing, so no
7687 * write requests running. We should be safe
7688 */
d9771f5e
XN		 7689 ret = log_init(conf, rdev, false);
7690 if (ret)
7691 return ret;
7692
7693 ret = r5l_start(conf->log);
7694 if (ret)
7695 return ret;
7696
f6b6ec5c
SL		 7697 return 0;
7698 }
7f0da59b
N		 7699 if (mddev->recovery_disabled == conf->recovery_disabled)
7700 return -EBUSY;
7701
dc10c643 7702 if (rdev->saved_raid_disk < 0 && has_failed(conf))
1da177e4 7703 /* no point adding a device */
199050ea 7704 return -EINVAL;
1da177e4 7705
6c2fce2e
NB		 7706 if (rdev->raid_disk >= 0)
7707 first = last = rdev->raid_disk;
1da177e4
LT		 7708
7709 /*
16a53ecc
N		 7710 * find the disk ... but prefer rdev->saved_raid_disk
7711 * if possible.
1da177e4 7712 */
16a53ecc 7713 if (rdev->saved_raid_disk >= 0 &&
6c2fce2e 7714 rdev->saved_raid_disk >= first &&
16a53ecc 7715 conf->disks[rdev->saved_raid_disk].rdev == NULL)
5cfb22a1
N		 7716 first = rdev->saved_raid_disk;
7717
7718 for (disk = first; disk <= last; disk++) {
7bfec5f3
N		 7719 p = conf->disks + disk;
7720 if (p->rdev == NULL) {
b2d444d7 7721 clear_bit(In_sync, &rdev->flags);
1da177e4 7722 rdev->raid_disk = disk;
72626685
N		 7723 if (rdev->saved_raid_disk != disk)
7724 conf->fullsync = 1;
d6065f7b 7725 rcu_assign_pointer(p->rdev, rdev);
6358c239
AP		 7726
7727 err = log_modify(conf, rdev, true);
7728
5cfb22a1 7729 goto out;
1da177e4 7730 }
5cfb22a1
N		 7731 }
7732 for (disk = first; disk <= last; disk++) {
7733 p = conf->disks + disk;
7bfec5f3
N		 7734 if (test_bit(WantReplacement, &p->rdev->flags) &&
7735 p->replacement == NULL) {
7736 clear_bit(In_sync, &rdev->flags);
7737 set_bit(Replacement, &rdev->flags);
7738 rdev->raid_disk = disk;
7739 err = 0;
7740 conf->fullsync = 1;
7741 rcu_assign_pointer(p->replacement, rdev);
7742 break;
7743 }
7744 }
5cfb22a1 7745out:
1da177e4 7746 print_raid5_conf(conf);
199050ea 7747 return err;
1da177e4
LT		 7748}
7749
fd01b88c 7750static int raid5_resize(struct mddev *mddev, sector_t sectors)
1da177e4
LT		 7751{
7752 /* no resync is happening, and there is enough space
7753 * on all devices, so we can resize.
7754 * We need to make sure resync covers any new space.
7755 * If the array is shrinking we should possibly wait until
7756 * any io in the removed space completes, but it hardly seems
7757 * worth it.
7758 */
a4a6125a 7759 sector_t newsize;
3cb5edf4
N		 7760 struct r5conf *conf = mddev->private;
7761
e254de6b 7762 if (raid5_has_log(conf) || raid5_has_ppl(conf))
713cf5a6 7763 return -EINVAL;
3cb5edf4 7764 sectors &= ~((sector_t)conf->chunk_sectors - 1);
a4a6125a
N		 7765 newsize = raid5_size(mddev, sectors, mddev->raid_disks);
7766 if (mddev->external_size &&
7767 mddev->array_sectors > newsize)
b522adcd 7768 return -EINVAL;
a4a6125a 7769 if (mddev->bitmap) {
e64e4018 7770 int ret = md_bitmap_resize(mddev->bitmap, sectors, 0, 0);
a4a6125a
N		 7771 if (ret)
7772 return ret;
7773 }
7774 md_set_array_sectors(mddev, newsize);
b098636c
N		 7775 if (sectors > mddev->dev_sectors &&
7776 mddev->recovery_cp > mddev->dev_sectors) {
58c0fed4 7777 mddev->recovery_cp = mddev->dev_sectors;
1da177e4
LT		 7778 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
7779 }
58c0fed4 7780 mddev->dev_sectors = sectors;
4b5c7ae8 7781 mddev->resync_max_sectors = sectors;
1da177e4
LT		 7782 return 0;
7783}
7784
fd01b88c 7785static int check_stripe_cache(struct mddev *mddev)
01ee22b4
N		 7786{
7787 /* Can only proceed if there are plenty of stripe_heads.
7788 * We need a minimum of one full stripe,, and for sensible progress
7789 * it is best to have about 4 times that.
7790 * If we require 4 times, then the default 256 4K stripe_heads will
7791 * allow for chunk sizes up to 256K, which is probably OK.
7792 * If the chunk size is greater, user-space should request more
7793 * stripe_heads first.
7794 */
d1688a6d 7795 struct r5conf *conf = mddev->private;
01ee22b4 7796 if (((mddev->chunk_sectors << 9) / STRIPE_SIZE) * 4
edbe83ab 7797 > conf->min_nr_stripes ||
01ee22b4 7798 ((mddev->new_chunk_sectors << 9) / STRIPE_SIZE) * 4
edbe83ab 7799 > conf->min_nr_stripes) {
cc6167b4
N		 7800 pr_warn("md/raid:%s: reshape: not enough stripes. Needed %lu\n",
7801 mdname(mddev),
7802 ((max(mddev->chunk_sectors, mddev->new_chunk_sectors) << 9)
7803 / STRIPE_SIZE)*4);
01ee22b4
N		 7804 return 0;
7805 }
7806 return 1;
7807}
7808
fd01b88c 7809static int check_reshape(struct mddev *mddev)
29269553 7810{
d1688a6d 7811 struct r5conf *conf = mddev->private;
29269553 7812
e254de6b 7813 if (raid5_has_log(conf) || raid5_has_ppl(conf))
713cf5a6 7814 return -EINVAL;
88ce4930
N		 7815 if (mddev->delta_disks == 0 &&
7816 mddev->new_layout == mddev->layout &&
664e7c41 7817 mddev->new_chunk_sectors == mddev->chunk_sectors)
50ac168a 7818 return 0; /* nothing to do */
674806d6 7819 if (has_failed(conf))
ec32a2bd 7820 return -EINVAL;
fdcfbbb6 7821 if (mddev->delta_disks < 0 && mddev->reshape_position == MaxSector) {
ec32a2bd
N		 7822 /* We might be able to shrink, but the devices must
7823 * be made bigger first.
7824 * For raid6, 4 is the minimum size.
7825 * Otherwise 2 is the minimum
7826 */
7827 int min = 2;
7828 if (mddev->level == 6)
7829 min = 4;
7830 if (mddev->raid_disks + mddev->delta_disks < min)
7831 return -EINVAL;
7832 }
29269553 7833
01ee22b4 7834 if (!check_stripe_cache(mddev))
29269553 7835 return -ENOSPC;
29269553 7836
738a2738
N		 7837 if (mddev->new_chunk_sectors > mddev->chunk_sectors ||
7838 mddev->delta_disks > 0)
7839 if (resize_chunks(conf,
7840 conf->previous_raid_disks
7841 + max(0, mddev->delta_disks),
7842 max(mddev->new_chunk_sectors,
7843 mddev->chunk_sectors)
7844 ) < 0)
7845 return -ENOMEM;
845b9e22
AP		 7846
7847 if (conf->previous_raid_disks + mddev->delta_disks <= conf->pool_size)
7848 return 0; /* never bother to shrink */
e56108d6
N		 7849 return resize_stripes(conf, (conf->previous_raid_disks
7850 + mddev->delta_disks));
63c70c4f
N		 7851}
7852
fd01b88c 7853static int raid5_start_reshape(struct mddev *mddev)
63c70c4f 7854{
d1688a6d 7855 struct r5conf *conf = mddev->private;
3cb03002 7856 struct md_rdev *rdev;
63c70c4f 7857 int spares = 0;
c04be0aa 7858 unsigned long flags;
63c70c4f 7859
f416885e 7860 if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
63c70c4f
N		 7861 return -EBUSY;
7862
01ee22b4
N		 7863 if (!check_stripe_cache(mddev))
7864 return -ENOSPC;
7865
30b67645
N		 7866 if (has_failed(conf))
7867 return -EINVAL;
7868
c6563a8c 7869 rdev_for_each(rdev, mddev) {
469518a3
N		 7870 if (!test_bit(In_sync, &rdev->flags)
7871 && !test_bit(Faulty, &rdev->flags))
29269553 7872 spares++;
c6563a8c 7873 }
63c70c4f 7874
f416885e 7875 if (spares - mddev->degraded < mddev->delta_disks - conf->max_degraded)
29269553
N		 7876 /* Not enough devices even to make a degraded array
7877 * of that size
7878 */
7879 return -EINVAL;
7880
ec32a2bd
N		 7881 /* Refuse to reduce size of the array. Any reductions in
7882 * array size must be through explicit setting of array_size
7883 * attribute.
7884 */
7885 if (raid5_size(mddev, 0, conf->raid_disks + mddev->delta_disks)
7886 < mddev->array_sectors) {
cc6167b4
N		 7887 pr_warn("md/raid:%s: array size must be reduced before number of disks\n",
7888 mdname(mddev));
ec32a2bd
N		 7889 return -EINVAL;
7890 }
7891
f6705578 7892 atomic_set(&conf->reshape_stripes, 0);
29269553 7893 spin_lock_irq(&conf->device_lock);
c46501b2 7894 write_seqcount_begin(&conf->gen_lock);
29269553 7895 conf->previous_raid_disks = conf->raid_disks;
63c70c4f 7896 conf->raid_disks += mddev->delta_disks;
09c9e5fa
AN		 7897 conf->prev_chunk_sectors = conf->chunk_sectors;
7898 conf->chunk_sectors = mddev->new_chunk_sectors;
88ce4930
N		 7899 conf->prev_algo = conf->algorithm;
7900 conf->algorithm = mddev->new_layout;
05616be5
N		 7901 conf->generation++;
7902 /* Code that selects data_offset needs to see the generation update
7903 * if reshape_progress has been set - so a memory barrier needed.
7904 */
7905 smp_mb();
2c810cdd 7906 if (mddev->reshape_backwards)
fef9c61f
N		 7907 conf->reshape_progress = raid5_size(mddev, 0, 0);
7908 else
7909 conf->reshape_progress = 0;
7910 conf->reshape_safe = conf->reshape_progress;
c46501b2 7911 write_seqcount_end(&conf->gen_lock);
29269553
N		 7912 spin_unlock_irq(&conf->device_lock);
7913
4d77e3ba
N		 7914 /* Now make sure any requests that proceeded on the assumption
7915 * the reshape wasn't running - like Discard or Read - have
7916 * completed.
7917 */
7918 mddev_suspend(mddev);
7919 mddev_resume(mddev);
7920
29269553
N		 7921 /* Add some new drives, as many as will fit.
7922 * We know there are enough to make the newly sized array work.
3424bf6a
N		 7923 * Don't add devices if we are reducing the number of
7924 * devices in the array. This is because it is not possible
7925 * to correctly record the "partially reconstructed" state of
7926 * such devices during the reshape and confusion could result.
29269553 7927 */
87a8dec9 7928 if (mddev->delta_disks >= 0) {
dafb20fa 7929 rdev_for_each(rdev, mddev)
87a8dec9
N		 7930 if (rdev->raid_disk < 0 &&
7931 !test_bit(Faulty, &rdev->flags)) {
7932 if (raid5_add_disk(mddev, rdev) == 0) {
87a8dec9 7933 if (rdev->raid_disk
9d4c7d87 7934 >= conf->previous_raid_disks)
87a8dec9 7935 set_bit(In_sync, &rdev->flags);
9d4c7d87 7936 else
87a8dec9 7937 rdev->recovery_offset = 0;
36fad858
NK		 7938
7939 if (sysfs_link_rdev(mddev, rdev))
87a8dec9 7940 /* Failure here is OK */;
50da0840 7941 }
87a8dec9
N		 7942 } else if (rdev->raid_disk >= conf->previous_raid_disks
7943 && !test_bit(Faulty, &rdev->flags)) {
7944 /* This is a spare that was manually added */
7945 set_bit(In_sync, &rdev->flags);
87a8dec9 7946 }
29269553 7947
87a8dec9
N		 7948 /* When a reshape changes the number of devices,
7949 * ->degraded is measured against the larger of the
7950 * pre and post number of devices.
7951 */
ec32a2bd 7952 spin_lock_irqsave(&conf->device_lock, flags);
2e38a37f 7953 mddev->degraded = raid5_calc_degraded(conf);
ec32a2bd
N		 7954 spin_unlock_irqrestore(&conf->device_lock, flags);
7955 }
63c70c4f 7956 mddev->raid_disks = conf->raid_disks;
e516402c 7957 mddev->reshape_position = conf->reshape_progress;
2953079c 7958 set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
f6705578 7959
29269553
N		 7960 clear_bit(MD_RECOVERY_SYNC, &mddev->recovery);
7961 clear_bit(MD_RECOVERY_CHECK, &mddev->recovery);
ea358cd0 7962 clear_bit(MD_RECOVERY_DONE, &mddev->recovery);
29269553
N		 7963 set_bit(MD_RECOVERY_RESHAPE, &mddev->recovery);
7964 set_bit(MD_RECOVERY_RUNNING, &mddev->recovery);
7965 mddev->sync_thread = md_register_thread(md_do_sync, mddev,
0da3c619 7966 "reshape");
29269553
N		 7967 if (!mddev->sync_thread) {
7968 mddev->recovery = 0;
7969 spin_lock_irq(&conf->device_lock);
ba8805b9 7970 write_seqcount_begin(&conf->gen_lock);
29269553 7971 mddev->raid_disks = conf->raid_disks = conf->previous_raid_disks;
ba8805b9
N		 7972 mddev->new_chunk_sectors =
7973 conf->chunk_sectors = conf->prev_chunk_sectors;
7974 mddev->new_layout = conf->algorithm = conf->prev_algo;
05616be5
N		 7975 rdev_for_each(rdev, mddev)
7976 rdev->new_data_offset = rdev->data_offset;
7977 smp_wmb();
ba8805b9 7978 conf->generation --;
fef9c61f 7979 conf->reshape_progress = MaxSector;
1e3fa9bd 7980 mddev->reshape_position = MaxSector;
ba8805b9 7981 write_seqcount_end(&conf->gen_lock);
29269553
N		 7982 spin_unlock_irq(&conf->device_lock);
7983 return -EAGAIN;
7984 }
c8f517c4 7985 conf->reshape_checkpoint = jiffies;
29269553
N		 7986 md_wakeup_thread(mddev->sync_thread);
7987 md_new_event(mddev);
7988 return 0;
7989}
29269553 7990
ec32a2bd
N		 7991/* This is called from the reshape thread and should make any
7992 * changes needed in 'conf'
7993 */
d1688a6d 7994static void end_reshape(struct r5conf *conf)
29269553 7995{
29269553 7996
f6705578 7997 if (!test_bit(MD_RECOVERY_INTR, &conf->mddev->recovery)) {
db0505d3 7998 struct md_rdev *rdev;
f6705578 7999
f6705578 8000 spin_lock_irq(&conf->device_lock);
cea9c228 8001 conf->previous_raid_disks = conf->raid_disks;
b5d27718 8002 md_finish_reshape(conf->mddev);
05616be5 8003 smp_wmb();
fef9c61f 8004 conf->reshape_progress = MaxSector;
6cbd8148 8005 conf->mddev->reshape_position = MaxSector;
db0505d3
N		 8006 rdev_for_each(rdev, conf->mddev)
8007 if (rdev->raid_disk >= 0 &&
8008 !test_bit(Journal, &rdev->flags) &&
8009 !test_bit(In_sync, &rdev->flags))
8010 rdev->recovery_offset = MaxSector;
f6705578 8011 spin_unlock_irq(&conf->device_lock);
b0f9ec04 8012 wake_up(&conf->wait_for_overlap);
16a53ecc
N		 8013
8014 /* read-ahead size must cover two whole stripes, which is
8015 * 2 * (datadisks) * chunksize where 'n' is the number of raid devices
8016 */
4a5add49 8017 if (conf->mddev->queue) {
cea9c228 8018 int data_disks = conf->raid_disks - conf->max_degraded;
09c9e5fa 8019 int stripe = data_disks * ((conf->chunk_sectors << 9)
cea9c228 8020 / PAGE_SIZE);
dc3b17cc
JK		 8021 if (conf->mddev->queue->backing_dev_info->ra_pages < 2 * stripe)
8022 conf->mddev->queue->backing_dev_info->ra_pages = 2 * stripe;
16a53ecc 8023 }
29269553 8024 }
29269553
N		 8025}
8026
ec32a2bd
N		 8027/* This is called from the raid5d thread with mddev_lock held.
8028 * It makes config changes to the device.
8029 */
fd01b88c 8030static void raid5_finish_reshape(struct mddev *mddev)
cea9c228 8031{
d1688a6d 8032 struct r5conf *conf = mddev->private;
cea9c228
N		 8033
8034 if (!test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
8035
8876391e 8036 if (mddev->delta_disks <= 0) {
ec32a2bd 8037 int d;
908f4fbd 8038 spin_lock_irq(&conf->device_lock);
2e38a37f 8039 mddev->degraded = raid5_calc_degraded(conf);
908f4fbd 8040 spin_unlock_irq(&conf->device_lock);
ec32a2bd
N		 8041 for (d = conf->raid_disks ;
8042 d < conf->raid_disks - mddev->delta_disks;
1a67dde0 8043 d++) {
3cb03002 8044 struct md_rdev *rdev = conf->disks[d].rdev;
da7613b8
N		 8045 if (rdev)
8046 clear_bit(In_sync, &rdev->flags);
8047 rdev = conf->disks[d].replacement;
8048 if (rdev)
8049 clear_bit(In_sync, &rdev->flags);
1a67dde0 8050 }
cea9c228 8051 }
88ce4930 8052 mddev->layout = conf->algorithm;
09c9e5fa 8053 mddev->chunk_sectors = conf->chunk_sectors;
ec32a2bd
N		 8054 mddev->reshape_position = MaxSector;
8055 mddev->delta_disks = 0;
2c810cdd 8056 mddev->reshape_backwards = 0;
cea9c228
N		 8057 }
8058}
8059
b03e0ccb 8060static void raid5_quiesce(struct mddev *mddev, int quiesce)
72626685 8061{
d1688a6d 8062 struct r5conf *conf = mddev->private;
72626685 8063
b03e0ccb
N		 8064 if (quiesce) {
8065 /* stop all writes */
566c09c5 8066 lock_all_device_hash_locks_irq(conf);
64bd660b
N		 8067 /* '2' tells resync/reshape to pause so that all
8068 * active stripes can drain
8069 */
a39f7afd 8070 r5c_flush_cache(conf, INT_MAX);
64bd660b 8071 conf->quiesce = 2;
b1b46486 8072 wait_event_cmd(conf->wait_for_quiescent,
46031f9a
RBJ		 8073 atomic_read(&conf->active_stripes) == 0 &&
8074 atomic_read(&conf->active_aligned_reads) == 0,
566c09c5
SL		 8075 unlock_all_device_hash_locks_irq(conf),
8076 lock_all_device_hash_locks_irq(conf));
64bd660b 8077 conf->quiesce = 1;
566c09c5 8078 unlock_all_device_hash_locks_irq(conf);
64bd660b
N		 8079 /* allow reshape to continue */
8080 wake_up(&conf->wait_for_overlap);
b03e0ccb
N		 8081 } else {
8082 /* re-enable writes */
566c09c5 8083 lock_all_device_hash_locks_irq(conf);
72626685 8084 conf->quiesce = 0;
b1b46486 8085 wake_up(&conf->wait_for_quiescent);
e464eafd 8086 wake_up(&conf->wait_for_overlap);
566c09c5 8087 unlock_all_device_hash_locks_irq(conf);
72626685 8088 }
1532d9e8 8089 log_quiesce(conf, quiesce);
72626685 8090}
b15c2e57 8091
fd01b88c 8092static void *raid45_takeover_raid0(struct mddev *mddev, int level)
54071b38 8093{
e373ab10 8094 struct r0conf *raid0_conf = mddev->private;
d76c8420 8095 sector_t sectors;
54071b38 8096
f1b29bca 8097 /* for raid0 takeover only one zone is supported */
e373ab10 8098 if (raid0_conf->nr_strip_zones > 1) {
cc6167b4
N		 8099 pr_warn("md/raid:%s: cannot takeover raid0 with more than one zone.\n",
8100 mdname(mddev));
f1b29bca
DW		 8101 return ERR_PTR(-EINVAL);
8102 }
8103
e373ab10
N		 8104 sectors = raid0_conf->strip_zone[0].zone_end;
8105 sector_div(sectors, raid0_conf->strip_zone[0].nb_dev);
3b71bd93 8106 mddev->dev_sectors = sectors;
f1b29bca 8107 mddev->new_level = level;
54071b38
TM		 8108 mddev->new_layout = ALGORITHM_PARITY_N;
8109 mddev->new_chunk_sectors = mddev->chunk_sectors;
8110 mddev->raid_disks += 1;
8111 mddev->delta_disks = 1;
8112 /* make sure it will be not marked as dirty */
8113 mddev->recovery_cp = MaxSector;
8114
8115 return setup_conf(mddev);
8116}
8117
fd01b88c 8118static void *raid5_takeover_raid1(struct mddev *mddev)
d562b0c4
N		 8119{
8120 int chunksect;
6995f0b2 8121 void *ret;
d562b0c4
N		 8122
8123 if (mddev->raid_disks != 2 ||
8124 mddev->degraded > 1)
8125 return ERR_PTR(-EINVAL);
8126
8127 /* Should check if there are write-behind devices? */
8128
8129 chunksect = 64*2; /* 64K by default */
8130
8131 /* The array must be an exact multiple of chunksize */
8132 while (chunksect && (mddev->array_sectors & (chunksect-1)))
8133 chunksect >>= 1;
8134
8135 if ((chunksect<<9) < STRIPE_SIZE)
8136 /* array size does not allow a suitable chunk size */
8137 return ERR_PTR(-EINVAL);
8138
8139 mddev->new_level = 5;
8140 mddev->new_layout = ALGORITHM_LEFT_SYMMETRIC;
664e7c41 8141 mddev->new_chunk_sectors = chunksect;
d562b0c4 8142
6995f0b2 8143 ret = setup_conf(mddev);
32cd7cbb 8144 if (!IS_ERR(ret))
394ed8e4
SL		 8145 mddev_clear_unsupported_flags(mddev,
8146 UNSUPPORTED_MDDEV_FLAGS);
6995f0b2 8147 return ret;
d562b0c4
N		 8148}
8149
fd01b88c 8150static void *raid5_takeover_raid6(struct mddev *mddev)
fc9739c6
N		 8151{
8152 int new_layout;
8153
8154 switch (mddev->layout) {
8155 case ALGORITHM_LEFT_ASYMMETRIC_6:
8156 new_layout = ALGORITHM_LEFT_ASYMMETRIC;
8157 break;
8158 case ALGORITHM_RIGHT_ASYMMETRIC_6:
8159 new_layout = ALGORITHM_RIGHT_ASYMMETRIC;
8160 break;
8161 case ALGORITHM_LEFT_SYMMETRIC_6:
8162 new_layout = ALGORITHM_LEFT_SYMMETRIC;
8163 break;
8164 case ALGORITHM_RIGHT_SYMMETRIC_6:
8165 new_layout = ALGORITHM_RIGHT_SYMMETRIC;
8166 break;
8167 case ALGORITHM_PARITY_0_6:
8168 new_layout = ALGORITHM_PARITY_0;
8169 break;
8170 case ALGORITHM_PARITY_N:
8171 new_layout = ALGORITHM_PARITY_N;
8172 break;
8173 default:
8174 return ERR_PTR(-EINVAL);
8175 }
8176 mddev->new_level = 5;
8177 mddev->new_layout = new_layout;
8178 mddev->delta_disks = -1;
8179 mddev->raid_disks -= 1;
8180 return setup_conf(mddev);
8181}
8182
fd01b88c 8183static int raid5_check_reshape(struct mddev *mddev)
b3546035 8184{
88ce4930
N		 8185 /* For a 2-drive array, the layout and chunk size can be changed
8186 * immediately as not restriping is needed.
8187 * For larger arrays we record the new value - after validation
8188 * to be used by a reshape pass.
b3546035 8189 */
d1688a6d 8190 struct r5conf *conf = mddev->private;
597a711b 8191 int new_chunk = mddev->new_chunk_sectors;
b3546035 8192
597a711b 8193 if (mddev->new_layout >= 0 && !algorithm_valid_raid5(mddev->new_layout))
b3546035
N		 8194 return -EINVAL;
8195 if (new_chunk > 0) {
0ba459d2 8196 if (!is_power_of_2(new_chunk))
b3546035 8197 return -EINVAL;
597a711b 8198 if (new_chunk < (PAGE_SIZE>>9))
b3546035 8199 return -EINVAL;
597a711b 8200 if (mddev->array_sectors & (new_chunk-1))
b3546035
N		 8201 /* not factor of array size */
8202 return -EINVAL;
8203 }
8204
8205 /* They look valid */
8206
88ce4930 8207 if (mddev->raid_disks == 2) {
597a711b
N		 8208 /* can make the change immediately */
8209 if (mddev->new_layout >= 0) {
8210 conf->algorithm = mddev->new_layout;
8211 mddev->layout = mddev->new_layout;
88ce4930
N		 8212 }
8213 if (new_chunk > 0) {
597a711b
N		 8214 conf->chunk_sectors = new_chunk ;
8215 mddev->chunk_sectors = new_chunk;
88ce4930 8216 }
2953079c 8217 set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
88ce4930 8218 md_wakeup_thread(mddev->thread);
b3546035 8219 }
50ac168a 8220 return check_reshape(mddev);
88ce4930
N		 8221}
8222
fd01b88c 8223static int raid6_check_reshape(struct mddev *mddev)
88ce4930 8224{
597a711b 8225 int new_chunk = mddev->new_chunk_sectors;
50ac168a 8226
597a711b 8227 if (mddev->new_layout >= 0 && !algorithm_valid_raid6(mddev->new_layout))
88ce4930 8228 return -EINVAL;
b3546035 8229 if (new_chunk > 0) {
0ba459d2 8230 if (!is_power_of_2(new_chunk))
88ce4930 8231 return -EINVAL;
597a711b 8232 if (new_chunk < (PAGE_SIZE >> 9))
88ce4930 8233 return -EINVAL;
597a711b 8234 if (mddev->array_sectors & (new_chunk-1))
88ce4930
N		 8235 /* not factor of array size */
8236 return -EINVAL;
b3546035 8237 }
88ce4930
N		 8238
8239 /* They look valid */
50ac168a 8240 return check_reshape(mddev);
b3546035
N		 8241}
8242
fd01b88c 8243static void *raid5_takeover(struct mddev *mddev)
d562b0c4
N		 8244{
8245 /* raid5 can take over:
f1b29bca 8246 * raid0 - if there is only one strip zone - make it a raid4 layout
d562b0c4
N		 8247 * raid1 - if there are two drives. We need to know the chunk size
8248 * raid4 - trivial - just use a raid4 layout.
8249 * raid6 - Providing it is a *_6 layout
d562b0c4 8250 */
f1b29bca
DW		 8251 if (mddev->level == 0)
8252 return raid45_takeover_raid0(mddev, 5);
d562b0c4
N		 8253 if (mddev->level == 1)
8254 return raid5_takeover_raid1(mddev);
e9d4758f
N		 8255 if (mddev->level == 4) {
8256 mddev->new_layout = ALGORITHM_PARITY_N;
8257 mddev->new_level = 5;
8258 return setup_conf(mddev);
8259 }
fc9739c6
N		 8260 if (mddev->level == 6)
8261 return raid5_takeover_raid6(mddev);
d562b0c4
N		 8262
8263 return ERR_PTR(-EINVAL);
8264}
8265
fd01b88c 8266static void *raid4_takeover(struct mddev *mddev)
a78d38a1 8267{
f1b29bca
DW		 8268 /* raid4 can take over:
8269 * raid0 - if there is only one strip zone
8270 * raid5 - if layout is right
a78d38a1 8271 */
f1b29bca
DW		 8272 if (mddev->level == 0)
8273 return raid45_takeover_raid0(mddev, 4);
a78d38a1
N		 8274 if (mddev->level == 5 &&
8275 mddev->layout == ALGORITHM_PARITY_N) {
8276 mddev->new_layout = 0;
8277 mddev->new_level = 4;
8278 return setup_conf(mddev);
8279 }
8280 return ERR_PTR(-EINVAL);
8281}
d562b0c4 8282
84fc4b56 8283static struct md_personality raid5_personality;
245f46c2 8284
fd01b88c 8285static void *raid6_takeover(struct mddev *mddev)
245f46c2
N		 8286{
8287 /* Currently can only take over a raid5. We map the
8288 * personality to an equivalent raid6 personality
8289 * with the Q block at the end.
8290 */
8291 int new_layout;
8292
8293 if (mddev->pers != &raid5_personality)
8294 return ERR_PTR(-EINVAL);
8295 if (mddev->degraded > 1)
8296 return ERR_PTR(-EINVAL);
8297 if (mddev->raid_disks > 253)
8298 return ERR_PTR(-EINVAL);
8299 if (mddev->raid_disks < 3)
8300 return ERR_PTR(-EINVAL);
8301
8302 switch (mddev->layout) {
8303 case ALGORITHM_LEFT_ASYMMETRIC:
8304 new_layout = ALGORITHM_LEFT_ASYMMETRIC_6;
8305 break;
8306 case ALGORITHM_RIGHT_ASYMMETRIC:
8307 new_layout = ALGORITHM_RIGHT_ASYMMETRIC_6;
8308 break;
8309 case ALGORITHM_LEFT_SYMMETRIC:
8310 new_layout = ALGORITHM_LEFT_SYMMETRIC_6;
8311 break;
8312 case ALGORITHM_RIGHT_SYMMETRIC:
8313 new_layout = ALGORITHM_RIGHT_SYMMETRIC_6;
8314 break;
8315 case ALGORITHM_PARITY_0:
8316 new_layout = ALGORITHM_PARITY_0_6;
8317 break;
8318 case ALGORITHM_PARITY_N:
8319 new_layout = ALGORITHM_PARITY_N;
8320 break;
8321 default:
8322 return ERR_PTR(-EINVAL);
8323 }
8324 mddev->new_level = 6;
8325 mddev->new_layout = new_layout;
8326 mddev->delta_disks = 1;
8327 mddev->raid_disks += 1;
8328 return setup_conf(mddev);
8329}
8330
ba903a3e
AP		 8331static int raid5_change_consistency_policy(struct mddev *mddev, const char *buf)
8332{
8333 struct r5conf *conf;
8334 int err;
8335
8336 err = mddev_lock(mddev);
8337 if (err)
8338 return err;
8339 conf = mddev->private;
8340 if (!conf) {
8341 mddev_unlock(mddev);
8342 return -ENODEV;
8343 }
8344
845b9e22 8345 if (strncmp(buf, "ppl", 3) == 0) {
0bb0c105 8346 /* ppl only works with RAID 5 */
845b9e22
AP		 8347 if (!raid5_has_ppl(conf) && conf->level == 5) {
8348 err = log_init(conf, NULL, true);
8349 if (!err) {
8350 err = resize_stripes(conf, conf->pool_size);
8351 if (err)
8352 log_exit(conf);
8353 }
0bb0c105
SL		 8354 } else
8355 err = -EINVAL;
8356 } else if (strncmp(buf, "resync", 6) == 0) {
8357 if (raid5_has_ppl(conf)) {
8358 mddev_suspend(mddev);
8359 log_exit(conf);
0bb0c105 8360 mddev_resume(mddev);
845b9e22 8361 err = resize_stripes(conf, conf->pool_size);
0bb0c105
SL		 8362 } else if (test_bit(MD_HAS_JOURNAL, &conf->mddev->flags) &&
8363 r5l_log_disk_error(conf)) {
8364 bool journal_dev_exists = false;
8365 struct md_rdev *rdev;
8366
8367 rdev_for_each(rdev, mddev)
8368 if (test_bit(Journal, &rdev->flags)) {
8369 journal_dev_exists = true;
8370 break;
8371 }
8372
8373 if (!journal_dev_exists) {
8374 mddev_suspend(mddev);
8375 clear_bit(MD_HAS_JOURNAL, &mddev->flags);
8376 mddev_resume(mddev);
8377 } else /* need remove journal device first */
8378 err = -EBUSY;
8379 } else
8380 err = -EINVAL;
ba903a3e
AP		 8381 } else {
8382 err = -EINVAL;
8383 }
8384
8385 if (!err)
8386 md_update_sb(mddev, 1);
8387
8388 mddev_unlock(mddev);
8389
8390 return err;
8391}
8392
d5d885fd
SL		 8393static int raid5_start(struct mddev *mddev)
8394{
8395 struct r5conf *conf = mddev->private;
8396
8397 return r5l_start(conf->log);
8398}
8399
84fc4b56 8400static struct md_personality raid6_personality =
16a53ecc
N		 8401{
8402 .name = "raid6",
8403 .level = 6,
8404 .owner = THIS_MODULE,
849674e4
SL		 8405 .make_request = raid5_make_request,
8406 .run = raid5_run,
d5d885fd 8407 .start = raid5_start,
afa0f557 8408 .free = raid5_free,
849674e4
SL		 8409 .status = raid5_status,
8410 .error_handler = raid5_error,
16a53ecc
N		 8411 .hot_add_disk = raid5_add_disk,
8412 .hot_remove_disk= raid5_remove_disk,
8413 .spare_active = raid5_spare_active,
849674e4 8414 .sync_request = raid5_sync_request,
16a53ecc 8415 .resize = raid5_resize,
80c3a6ce 8416 .size = raid5_size,
50ac168a 8417 .check_reshape = raid6_check_reshape,
f416885e 8418 .start_reshape = raid5_start_reshape,
cea9c228 8419 .finish_reshape = raid5_finish_reshape,
16a53ecc 8420 .quiesce = raid5_quiesce,
245f46c2 8421 .takeover = raid6_takeover,
5c675f83 8422 .congested = raid5_congested,
0bb0c105 8423 .change_consistency_policy = raid5_change_consistency_policy,
16a53ecc 8424};
84fc4b56 8425static struct md_personality raid5_personality =
1da177e4
LT		 8426{
8427 .name = "raid5",
2604b703 8428 .level = 5,
1da177e4 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,
1da177e4
LT		 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,
1da177e4 8440 .resize = raid5_resize,
80c3a6ce 8441 .size = raid5_size,
63c70c4f
N		 8442 .check_reshape = raid5_check_reshape,
8443 .start_reshape = raid5_start_reshape,
cea9c228 8444 .finish_reshape = raid5_finish_reshape,
72626685 8445 .quiesce = raid5_quiesce,
d562b0c4 8446 .takeover = raid5_takeover,
5c675f83 8447 .congested = raid5_congested,
ba903a3e 8448 .change_consistency_policy = raid5_change_consistency_policy,
1da177e4
LT		 8449};
8450
84fc4b56 8451static struct md_personality raid4_personality =
1da177e4 8452{
2604b703
N		 8453 .name = "raid4",
8454 .level = 4,
8455 .owner = THIS_MODULE,
849674e4
SL		 8456 .make_request = raid5_make_request,
8457 .run = raid5_run,
d5d885fd 8458 .start = raid5_start,
afa0f557 8459 .free = raid5_free,
849674e4
SL		 8460 .status = raid5_status,
8461 .error_handler = raid5_error,
2604b703
N		 8462 .hot_add_disk = raid5_add_disk,
8463 .hot_remove_disk= raid5_remove_disk,
8464 .spare_active = raid5_spare_active,
849674e4 8465 .sync_request = raid5_sync_request,
2604b703 8466 .resize = raid5_resize,
80c3a6ce 8467 .size = raid5_size,
3d37890b
N		 8468 .check_reshape = raid5_check_reshape,
8469 .start_reshape = raid5_start_reshape,
cea9c228 8470 .finish_reshape = raid5_finish_reshape,
2604b703 8471 .quiesce = raid5_quiesce,
a78d38a1 8472 .takeover = raid4_takeover,
5c675f83 8473 .congested = raid5_congested,
0bb0c105 8474 .change_consistency_policy = raid5_change_consistency_policy,
2604b703
N		 8475};
8476
8477static int __init raid5_init(void)
8478{
29c6d1bb
SAS		 8479 int ret;
8480
851c30c9
SL		 8481 raid5_wq = alloc_workqueue("raid5wq",
8482 WQ_UNBOUND|WQ_MEM_RECLAIM|WQ_CPU_INTENSIVE|WQ_SYSFS, 0);
8483 if (!raid5_wq)
8484 return -ENOMEM;
29c6d1bb
SAS		 8485
8486 ret = cpuhp_setup_state_multi(CPUHP_MD_RAID5_PREPARE,
8487 "md/raid5:prepare",
8488 raid456_cpu_up_prepare,
8489 raid456_cpu_dead);
8490 if (ret) {
8491 destroy_workqueue(raid5_wq);
8492 return ret;
8493 }
16a53ecc 8494 register_md_personality(&raid6_personality);
2604b703
N		 8495 register_md_personality(&raid5_personality);
8496 register_md_personality(&raid4_personality);
8497 return 0;
1da177e4
LT		 8498}
8499
2604b703 8500static void raid5_exit(void)
1da177e4 8501{
16a53ecc 8502 unregister_md_personality(&raid6_personality);
2604b703
N		 8503 unregister_md_personality(&raid5_personality);
8504 unregister_md_personality(&raid4_personality);
29c6d1bb 8505 cpuhp_remove_multi_state(CPUHP_MD_RAID5_PREPARE);
851c30c9 8506 destroy_workqueue(raid5_wq);
1da177e4
LT		 8507}
8508
8509module_init(raid5_init);
8510module_exit(raid5_exit);
8511MODULE_LICENSE("GPL");
0efb9e61 8512MODULE_DESCRIPTION("RAID4/5/6 (striping with parity) personality for MD");
1da177e4 8513MODULE_ALIAS("md-personality-4"); /* RAID5 */
d9d166c2
N		 8514MODULE_ALIAS("md-raid5");
8515MODULE_ALIAS("md-raid4");
2604b703
N		 8516MODULE_ALIAS("md-level-5");
8517MODULE_ALIAS("md-level-4");
16a53ecc
N		 8518MODULE_ALIAS("md-personality-8"); /* RAID6 */
8519MODULE_ALIAS("md-raid6");
8520MODULE_ALIAS("md-level-6");
8521
8522/* This used to be two separate modules, they were: */
8523MODULE_ALIAS("raid5");
8524MODULE_ALIAS("raid6");
Linux 6.x block layer and io_uring tree(s)