Loading...
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * raid1.c : Multiple Devices driver for Linux
4 *
5 * Copyright (C) 1999, 2000, 2001 Ingo Molnar, Red Hat
6 *
7 * Copyright (C) 1996, 1997, 1998 Ingo Molnar, Miguel de Icaza, Gadi Oxman
8 *
9 * RAID-1 management functions.
10 *
11 * Better read-balancing code written by Mika Kuoppala <miku@iki.fi>, 2000
12 *
13 * Fixes to reconstruction by Jakob Østergaard" <jakob@ostenfeld.dk>
14 * Various fixes by Neil Brown <neilb@cse.unsw.edu.au>
15 *
16 * Changes by Peter T. Breuer <ptb@it.uc3m.es> 31/1/2003 to support
17 * bitmapped intelligence in resync:
18 *
19 * - bitmap marked during normal i/o
20 * - bitmap used to skip nondirty blocks during sync
21 *
22 * Additions to bitmap code, (C) 2003-2004 Paul Clements, SteelEye Technology:
23 * - persistent bitmap code
24 */
25
26#include <linux/slab.h>
27#include <linux/delay.h>
28#include <linux/blkdev.h>
29#include <linux/module.h>
30#include <linux/seq_file.h>
31#include <linux/ratelimit.h>
32#include <linux/interval_tree_generic.h>
33
34#include <trace/events/block.h>
35
36#include "md.h"
37#include "raid1.h"
38#include "md-bitmap.h"
39
40#define UNSUPPORTED_MDDEV_FLAGS \
41 ((1L << MD_HAS_JOURNAL) | \
42 (1L << MD_JOURNAL_CLEAN) | \
43 (1L << MD_HAS_PPL) | \
44 (1L << MD_HAS_MULTIPLE_PPLS))
45
46static void allow_barrier(struct r1conf *conf, sector_t sector_nr);
47static void lower_barrier(struct r1conf *conf, sector_t sector_nr);
48
49#define raid1_log(md, fmt, args...) \
50 do { if ((md)->queue) blk_add_trace_msg((md)->queue, "raid1 " fmt, ##args); } while (0)
51
52#define RAID_1_10_NAME "raid1"
53#include "raid1-10.c"
54
55#define START(node) ((node)->start)
56#define LAST(node) ((node)->last)
57INTERVAL_TREE_DEFINE(struct serial_info, node, sector_t, _subtree_last,
58 START, LAST, static inline, raid1_rb);
59
60static int check_and_add_serial(struct md_rdev *rdev, struct r1bio *r1_bio,
61 struct serial_info *si, int idx)
62{
63 unsigned long flags;
64 int ret = 0;
65 sector_t lo = r1_bio->sector;
66 sector_t hi = lo + r1_bio->sectors;
67 struct serial_in_rdev *serial = &rdev->serial[idx];
68
69 spin_lock_irqsave(&serial->serial_lock, flags);
70 /* collision happened */
71 if (raid1_rb_iter_first(&serial->serial_rb, lo, hi))
72 ret = -EBUSY;
73 else {
74 si->start = lo;
75 si->last = hi;
76 raid1_rb_insert(si, &serial->serial_rb);
77 }
78 spin_unlock_irqrestore(&serial->serial_lock, flags);
79
80 return ret;
81}
82
83static void wait_for_serialization(struct md_rdev *rdev, struct r1bio *r1_bio)
84{
85 struct mddev *mddev = rdev->mddev;
86 struct serial_info *si;
87 int idx = sector_to_idx(r1_bio->sector);
88 struct serial_in_rdev *serial = &rdev->serial[idx];
89
90 if (WARN_ON(!mddev->serial_info_pool))
91 return;
92 si = mempool_alloc(mddev->serial_info_pool, GFP_NOIO);
93 wait_event(serial->serial_io_wait,
94 check_and_add_serial(rdev, r1_bio, si, idx) == 0);
95}
96
97static void remove_serial(struct md_rdev *rdev, sector_t lo, sector_t hi)
98{
99 struct serial_info *si;
100 unsigned long flags;
101 int found = 0;
102 struct mddev *mddev = rdev->mddev;
103 int idx = sector_to_idx(lo);
104 struct serial_in_rdev *serial = &rdev->serial[idx];
105
106 spin_lock_irqsave(&serial->serial_lock, flags);
107 for (si = raid1_rb_iter_first(&serial->serial_rb, lo, hi);
108 si; si = raid1_rb_iter_next(si, lo, hi)) {
109 if (si->start == lo && si->last == hi) {
110 raid1_rb_remove(si, &serial->serial_rb);
111 mempool_free(si, mddev->serial_info_pool);
112 found = 1;
113 break;
114 }
115 }
116 if (!found)
117 WARN(1, "The write IO is not recorded for serialization\n");
118 spin_unlock_irqrestore(&serial->serial_lock, flags);
119 wake_up(&serial->serial_io_wait);
120}
121
122/*
123 * for resync bio, r1bio pointer can be retrieved from the per-bio
124 * 'struct resync_pages'.
125 */
126static inline struct r1bio *get_resync_r1bio(struct bio *bio)
127{
128 return get_resync_pages(bio)->raid_bio;
129}
130
131static void * r1bio_pool_alloc(gfp_t gfp_flags, void *data)
132{
133 struct pool_info *pi = data;
134 int size = offsetof(struct r1bio, bios[pi->raid_disks]);
135
136 /* allocate a r1bio with room for raid_disks entries in the bios array */
137 return kzalloc(size, gfp_flags);
138}
139
140#define RESYNC_DEPTH 32
141#define RESYNC_SECTORS (RESYNC_BLOCK_SIZE >> 9)
142#define RESYNC_WINDOW (RESYNC_BLOCK_SIZE * RESYNC_DEPTH)
143#define RESYNC_WINDOW_SECTORS (RESYNC_WINDOW >> 9)
144#define CLUSTER_RESYNC_WINDOW (16 * RESYNC_WINDOW)
145#define CLUSTER_RESYNC_WINDOW_SECTORS (CLUSTER_RESYNC_WINDOW >> 9)
146
147static void * r1buf_pool_alloc(gfp_t gfp_flags, void *data)
148{
149 struct pool_info *pi = data;
150 struct r1bio *r1_bio;
151 struct bio *bio;
152 int need_pages;
153 int j;
154 struct resync_pages *rps;
155
156 r1_bio = r1bio_pool_alloc(gfp_flags, pi);
157 if (!r1_bio)
158 return NULL;
159
160 rps = kmalloc_array(pi->raid_disks, sizeof(struct resync_pages),
161 gfp_flags);
162 if (!rps)
163 goto out_free_r1bio;
164
165 /*
166 * Allocate bios : 1 for reading, n-1 for writing
167 */
168 for (j = pi->raid_disks ; j-- ; ) {
169 bio = bio_kmalloc(RESYNC_PAGES, gfp_flags);
170 if (!bio)
171 goto out_free_bio;
172 bio_init(bio, NULL, bio->bi_inline_vecs, RESYNC_PAGES, 0);
173 r1_bio->bios[j] = bio;
174 }
175 /*
176 * Allocate RESYNC_PAGES data pages and attach them to
177 * the first bio.
178 * If this is a user-requested check/repair, allocate
179 * RESYNC_PAGES for each bio.
180 */
181 if (test_bit(MD_RECOVERY_REQUESTED, &pi->mddev->recovery))
182 need_pages = pi->raid_disks;
183 else
184 need_pages = 1;
185 for (j = 0; j < pi->raid_disks; j++) {
186 struct resync_pages *rp = &rps[j];
187
188 bio = r1_bio->bios[j];
189
190 if (j < need_pages) {
191 if (resync_alloc_pages(rp, gfp_flags))
192 goto out_free_pages;
193 } else {
194 memcpy(rp, &rps[0], sizeof(*rp));
195 resync_get_all_pages(rp);
196 }
197
198 rp->raid_bio = r1_bio;
199 bio->bi_private = rp;
200 }
201
202 r1_bio->master_bio = NULL;
203
204 return r1_bio;
205
206out_free_pages:
207 while (--j >= 0)
208 resync_free_pages(&rps[j]);
209
210out_free_bio:
211 while (++j < pi->raid_disks) {
212 bio_uninit(r1_bio->bios[j]);
213 kfree(r1_bio->bios[j]);
214 }
215 kfree(rps);
216
217out_free_r1bio:
218 rbio_pool_free(r1_bio, data);
219 return NULL;
220}
221
222static void r1buf_pool_free(void *__r1_bio, void *data)
223{
224 struct pool_info *pi = data;
225 int i;
226 struct r1bio *r1bio = __r1_bio;
227 struct resync_pages *rp = NULL;
228
229 for (i = pi->raid_disks; i--; ) {
230 rp = get_resync_pages(r1bio->bios[i]);
231 resync_free_pages(rp);
232 bio_uninit(r1bio->bios[i]);
233 kfree(r1bio->bios[i]);
234 }
235
236 /* resync pages array stored in the 1st bio's .bi_private */
237 kfree(rp);
238
239 rbio_pool_free(r1bio, data);
240}
241
242static void put_all_bios(struct r1conf *conf, struct r1bio *r1_bio)
243{
244 int i;
245
246 for (i = 0; i < conf->raid_disks * 2; i++) {
247 struct bio **bio = r1_bio->bios + i;
248 if (!BIO_SPECIAL(*bio))
249 bio_put(*bio);
250 *bio = NULL;
251 }
252}
253
254static void free_r1bio(struct r1bio *r1_bio)
255{
256 struct r1conf *conf = r1_bio->mddev->private;
257
258 put_all_bios(conf, r1_bio);
259 mempool_free(r1_bio, &conf->r1bio_pool);
260}
261
262static void put_buf(struct r1bio *r1_bio)
263{
264 struct r1conf *conf = r1_bio->mddev->private;
265 sector_t sect = r1_bio->sector;
266 int i;
267
268 for (i = 0; i < conf->raid_disks * 2; i++) {
269 struct bio *bio = r1_bio->bios[i];
270 if (bio->bi_end_io)
271 rdev_dec_pending(conf->mirrors[i].rdev, r1_bio->mddev);
272 }
273
274 mempool_free(r1_bio, &conf->r1buf_pool);
275
276 lower_barrier(conf, sect);
277}
278
279static void reschedule_retry(struct r1bio *r1_bio)
280{
281 unsigned long flags;
282 struct mddev *mddev = r1_bio->mddev;
283 struct r1conf *conf = mddev->private;
284 int idx;
285
286 idx = sector_to_idx(r1_bio->sector);
287 spin_lock_irqsave(&conf->device_lock, flags);
288 list_add(&r1_bio->retry_list, &conf->retry_list);
289 atomic_inc(&conf->nr_queued[idx]);
290 spin_unlock_irqrestore(&conf->device_lock, flags);
291
292 wake_up(&conf->wait_barrier);
293 md_wakeup_thread(mddev->thread);
294}
295
296/*
297 * raid_end_bio_io() is called when we have finished servicing a mirrored
298 * operation and are ready to return a success/failure code to the buffer
299 * cache layer.
300 */
301static void call_bio_endio(struct r1bio *r1_bio)
302{
303 struct bio *bio = r1_bio->master_bio;
304
305 if (!test_bit(R1BIO_Uptodate, &r1_bio->state))
306 bio->bi_status = BLK_STS_IOERR;
307
308 bio_endio(bio);
309}
310
311static void raid_end_bio_io(struct r1bio *r1_bio)
312{
313 struct bio *bio = r1_bio->master_bio;
314 struct r1conf *conf = r1_bio->mddev->private;
315 sector_t sector = r1_bio->sector;
316
317 /* if nobody has done the final endio yet, do it now */
318 if (!test_and_set_bit(R1BIO_Returned, &r1_bio->state)) {
319 pr_debug("raid1: sync end %s on sectors %llu-%llu\n",
320 (bio_data_dir(bio) == WRITE) ? "write" : "read",
321 (unsigned long long) bio->bi_iter.bi_sector,
322 (unsigned long long) bio_end_sector(bio) - 1);
323
324 call_bio_endio(r1_bio);
325 }
326
327 free_r1bio(r1_bio);
328 /*
329 * Wake up any possible resync thread that waits for the device
330 * to go idle. All I/Os, even write-behind writes, are done.
331 */
332 allow_barrier(conf, sector);
333}
334
335/*
336 * Update disk head position estimator based on IRQ completion info.
337 */
338static inline void update_head_pos(int disk, struct r1bio *r1_bio)
339{
340 struct r1conf *conf = r1_bio->mddev->private;
341
342 conf->mirrors[disk].head_position =
343 r1_bio->sector + (r1_bio->sectors);
344}
345
346/*
347 * Find the disk number which triggered given bio
348 */
349static int find_bio_disk(struct r1bio *r1_bio, struct bio *bio)
350{
351 int mirror;
352 struct r1conf *conf = r1_bio->mddev->private;
353 int raid_disks = conf->raid_disks;
354
355 for (mirror = 0; mirror < raid_disks * 2; mirror++)
356 if (r1_bio->bios[mirror] == bio)
357 break;
358
359 BUG_ON(mirror == raid_disks * 2);
360 update_head_pos(mirror, r1_bio);
361
362 return mirror;
363}
364
365static void raid1_end_read_request(struct bio *bio)
366{
367 int uptodate = !bio->bi_status;
368 struct r1bio *r1_bio = bio->bi_private;
369 struct r1conf *conf = r1_bio->mddev->private;
370 struct md_rdev *rdev = conf->mirrors[r1_bio->read_disk].rdev;
371
372 /*
373 * this branch is our 'one mirror IO has finished' event handler:
374 */
375 update_head_pos(r1_bio->read_disk, r1_bio);
376
377 if (uptodate)
378 set_bit(R1BIO_Uptodate, &r1_bio->state);
379 else if (test_bit(FailFast, &rdev->flags) &&
380 test_bit(R1BIO_FailFast, &r1_bio->state))
381 /* This was a fail-fast read so we definitely
382 * want to retry */
383 ;
384 else {
385 /* If all other devices have failed, we want to return
386 * the error upwards rather than fail the last device.
387 * Here we redefine "uptodate" to mean "Don't want to retry"
388 */
389 unsigned long flags;
390 spin_lock_irqsave(&conf->device_lock, flags);
391 if (r1_bio->mddev->degraded == conf->raid_disks ||
392 (r1_bio->mddev->degraded == conf->raid_disks-1 &&
393 test_bit(In_sync, &rdev->flags)))
394 uptodate = 1;
395 spin_unlock_irqrestore(&conf->device_lock, flags);
396 }
397
398 if (uptodate) {
399 raid_end_bio_io(r1_bio);
400 rdev_dec_pending(rdev, conf->mddev);
401 } else {
402 /*
403 * oops, read error:
404 */
405 pr_err_ratelimited("md/raid1:%s: %pg: rescheduling sector %llu\n",
406 mdname(conf->mddev),
407 rdev->bdev,
408 (unsigned long long)r1_bio->sector);
409 set_bit(R1BIO_ReadError, &r1_bio->state);
410 reschedule_retry(r1_bio);
411 /* don't drop the reference on read_disk yet */
412 }
413}
414
415static void close_write(struct r1bio *r1_bio)
416{
417 /* it really is the end of this request */
418 if (test_bit(R1BIO_BehindIO, &r1_bio->state)) {
419 bio_free_pages(r1_bio->behind_master_bio);
420 bio_put(r1_bio->behind_master_bio);
421 r1_bio->behind_master_bio = NULL;
422 }
423 /* clear the bitmap if all writes complete successfully */
424 md_bitmap_endwrite(r1_bio->mddev->bitmap, r1_bio->sector,
425 r1_bio->sectors,
426 !test_bit(R1BIO_Degraded, &r1_bio->state),
427 test_bit(R1BIO_BehindIO, &r1_bio->state));
428 md_write_end(r1_bio->mddev);
429}
430
431static void r1_bio_write_done(struct r1bio *r1_bio)
432{
433 if (!atomic_dec_and_test(&r1_bio->remaining))
434 return;
435
436 if (test_bit(R1BIO_WriteError, &r1_bio->state))
437 reschedule_retry(r1_bio);
438 else {
439 close_write(r1_bio);
440 if (test_bit(R1BIO_MadeGood, &r1_bio->state))
441 reschedule_retry(r1_bio);
442 else
443 raid_end_bio_io(r1_bio);
444 }
445}
446
447static void raid1_end_write_request(struct bio *bio)
448{
449 struct r1bio *r1_bio = bio->bi_private;
450 int behind = test_bit(R1BIO_BehindIO, &r1_bio->state);
451 struct r1conf *conf = r1_bio->mddev->private;
452 struct bio *to_put = NULL;
453 int mirror = find_bio_disk(r1_bio, bio);
454 struct md_rdev *rdev = conf->mirrors[mirror].rdev;
455 bool discard_error;
456 sector_t lo = r1_bio->sector;
457 sector_t hi = r1_bio->sector + r1_bio->sectors;
458
459 discard_error = bio->bi_status && bio_op(bio) == REQ_OP_DISCARD;
460
461 /*
462 * 'one mirror IO has finished' event handler:
463 */
464 if (bio->bi_status && !discard_error) {
465 set_bit(WriteErrorSeen, &rdev->flags);
466 if (!test_and_set_bit(WantReplacement, &rdev->flags))
467 set_bit(MD_RECOVERY_NEEDED, &
468 conf->mddev->recovery);
469
470 if (test_bit(FailFast, &rdev->flags) &&
471 (bio->bi_opf & MD_FAILFAST) &&
472 /* We never try FailFast to WriteMostly devices */
473 !test_bit(WriteMostly, &rdev->flags)) {
474 md_error(r1_bio->mddev, rdev);
475 }
476
477 /*
478 * When the device is faulty, it is not necessary to
479 * handle write error.
480 */
481 if (!test_bit(Faulty, &rdev->flags))
482 set_bit(R1BIO_WriteError, &r1_bio->state);
483 else {
484 /* Fail the request */
485 set_bit(R1BIO_Degraded, &r1_bio->state);
486 /* Finished with this branch */
487 r1_bio->bios[mirror] = NULL;
488 to_put = bio;
489 }
490 } else {
491 /*
492 * Set R1BIO_Uptodate in our master bio, so that we
493 * will return a good error code for to the higher
494 * levels even if IO on some other mirrored buffer
495 * fails.
496 *
497 * The 'master' represents the composite IO operation
498 * to user-side. So if something waits for IO, then it
499 * will wait for the 'master' bio.
500 */
501 sector_t first_bad;
502 int bad_sectors;
503
504 r1_bio->bios[mirror] = NULL;
505 to_put = bio;
506 /*
507 * Do not set R1BIO_Uptodate if the current device is
508 * rebuilding or Faulty. This is because we cannot use
509 * such device for properly reading the data back (we could
510 * potentially use it, if the current write would have felt
511 * before rdev->recovery_offset, but for simplicity we don't
512 * check this here.
513 */
514 if (test_bit(In_sync, &rdev->flags) &&
515 !test_bit(Faulty, &rdev->flags))
516 set_bit(R1BIO_Uptodate, &r1_bio->state);
517
518 /* Maybe we can clear some bad blocks. */
519 if (is_badblock(rdev, r1_bio->sector, r1_bio->sectors,
520 &first_bad, &bad_sectors) && !discard_error) {
521 r1_bio->bios[mirror] = IO_MADE_GOOD;
522 set_bit(R1BIO_MadeGood, &r1_bio->state);
523 }
524 }
525
526 if (behind) {
527 if (test_bit(CollisionCheck, &rdev->flags))
528 remove_serial(rdev, lo, hi);
529 if (test_bit(WriteMostly, &rdev->flags))
530 atomic_dec(&r1_bio->behind_remaining);
531
532 /*
533 * In behind mode, we ACK the master bio once the I/O
534 * has safely reached all non-writemostly
535 * disks. Setting the Returned bit ensures that this
536 * gets done only once -- we don't ever want to return
537 * -EIO here, instead we'll wait
538 */
539 if (atomic_read(&r1_bio->behind_remaining) >= (atomic_read(&r1_bio->remaining)-1) &&
540 test_bit(R1BIO_Uptodate, &r1_bio->state)) {
541 /* Maybe we can return now */
542 if (!test_and_set_bit(R1BIO_Returned, &r1_bio->state)) {
543 struct bio *mbio = r1_bio->master_bio;
544 pr_debug("raid1: behind end write sectors"
545 " %llu-%llu\n",
546 (unsigned long long) mbio->bi_iter.bi_sector,
547 (unsigned long long) bio_end_sector(mbio) - 1);
548 call_bio_endio(r1_bio);
549 }
550 }
551 } else if (rdev->mddev->serialize_policy)
552 remove_serial(rdev, lo, hi);
553 if (r1_bio->bios[mirror] == NULL)
554 rdev_dec_pending(rdev, conf->mddev);
555
556 /*
557 * Let's see if all mirrored write operations have finished
558 * already.
559 */
560 r1_bio_write_done(r1_bio);
561
562 if (to_put)
563 bio_put(to_put);
564}
565
566static sector_t align_to_barrier_unit_end(sector_t start_sector,
567 sector_t sectors)
568{
569 sector_t len;
570
571 WARN_ON(sectors == 0);
572 /*
573 * len is the number of sectors from start_sector to end of the
574 * barrier unit which start_sector belongs to.
575 */
576 len = round_up(start_sector + 1, BARRIER_UNIT_SECTOR_SIZE) -
577 start_sector;
578
579 if (len > sectors)
580 len = sectors;
581
582 return len;
583}
584
585/*
586 * This routine returns the disk from which the requested read should
587 * be done. There is a per-array 'next expected sequential IO' sector
588 * number - if this matches on the next IO then we use the last disk.
589 * There is also a per-disk 'last know head position' sector that is
590 * maintained from IRQ contexts, both the normal and the resync IO
591 * completion handlers update this position correctly. If there is no
592 * perfect sequential match then we pick the disk whose head is closest.
593 *
594 * If there are 2 mirrors in the same 2 devices, performance degrades
595 * because position is mirror, not device based.
596 *
597 * The rdev for the device selected will have nr_pending incremented.
598 */
599static int read_balance(struct r1conf *conf, struct r1bio *r1_bio, int *max_sectors)
600{
601 const sector_t this_sector = r1_bio->sector;
602 int sectors;
603 int best_good_sectors;
604 int best_disk, best_dist_disk, best_pending_disk;
605 int has_nonrot_disk;
606 int disk;
607 sector_t best_dist;
608 unsigned int min_pending;
609 struct md_rdev *rdev;
610 int choose_first;
611 int choose_next_idle;
612
613 /*
614 * Check if we can balance. We can balance on the whole
615 * device if no resync is going on, or below the resync window.
616 * We take the first readable disk when above the resync window.
617 */
618 retry:
619 sectors = r1_bio->sectors;
620 best_disk = -1;
621 best_dist_disk = -1;
622 best_dist = MaxSector;
623 best_pending_disk = -1;
624 min_pending = UINT_MAX;
625 best_good_sectors = 0;
626 has_nonrot_disk = 0;
627 choose_next_idle = 0;
628 clear_bit(R1BIO_FailFast, &r1_bio->state);
629
630 if ((conf->mddev->recovery_cp < this_sector + sectors) ||
631 (mddev_is_clustered(conf->mddev) &&
632 md_cluster_ops->area_resyncing(conf->mddev, READ, this_sector,
633 this_sector + sectors)))
634 choose_first = 1;
635 else
636 choose_first = 0;
637
638 for (disk = 0 ; disk < conf->raid_disks * 2 ; disk++) {
639 sector_t dist;
640 sector_t first_bad;
641 int bad_sectors;
642 unsigned int pending;
643 bool nonrot;
644
645 rdev = conf->mirrors[disk].rdev;
646 if (r1_bio->bios[disk] == IO_BLOCKED
647 || rdev == NULL
648 || test_bit(Faulty, &rdev->flags))
649 continue;
650 if (!test_bit(In_sync, &rdev->flags) &&
651 rdev->recovery_offset < this_sector + sectors)
652 continue;
653 if (test_bit(WriteMostly, &rdev->flags)) {
654 /* Don't balance among write-mostly, just
655 * use the first as a last resort */
656 if (best_dist_disk < 0) {
657 if (is_badblock(rdev, this_sector, sectors,
658 &first_bad, &bad_sectors)) {
659 if (first_bad <= this_sector)
660 /* Cannot use this */
661 continue;
662 best_good_sectors = first_bad - this_sector;
663 } else
664 best_good_sectors = sectors;
665 best_dist_disk = disk;
666 best_pending_disk = disk;
667 }
668 continue;
669 }
670 /* This is a reasonable device to use. It might
671 * even be best.
672 */
673 if (is_badblock(rdev, this_sector, sectors,
674 &first_bad, &bad_sectors)) {
675 if (best_dist < MaxSector)
676 /* already have a better device */
677 continue;
678 if (first_bad <= this_sector) {
679 /* cannot read here. If this is the 'primary'
680 * device, then we must not read beyond
681 * bad_sectors from another device..
682 */
683 bad_sectors -= (this_sector - first_bad);
684 if (choose_first && sectors > bad_sectors)
685 sectors = bad_sectors;
686 if (best_good_sectors > sectors)
687 best_good_sectors = sectors;
688
689 } else {
690 sector_t good_sectors = first_bad - this_sector;
691 if (good_sectors > best_good_sectors) {
692 best_good_sectors = good_sectors;
693 best_disk = disk;
694 }
695 if (choose_first)
696 break;
697 }
698 continue;
699 } else {
700 if ((sectors > best_good_sectors) && (best_disk >= 0))
701 best_disk = -1;
702 best_good_sectors = sectors;
703 }
704
705 if (best_disk >= 0)
706 /* At least two disks to choose from so failfast is OK */
707 set_bit(R1BIO_FailFast, &r1_bio->state);
708
709 nonrot = bdev_nonrot(rdev->bdev);
710 has_nonrot_disk |= nonrot;
711 pending = atomic_read(&rdev->nr_pending);
712 dist = abs(this_sector - conf->mirrors[disk].head_position);
713 if (choose_first) {
714 best_disk = disk;
715 break;
716 }
717 /* Don't change to another disk for sequential reads */
718 if (conf->mirrors[disk].next_seq_sect == this_sector
719 || dist == 0) {
720 int opt_iosize = bdev_io_opt(rdev->bdev) >> 9;
721 struct raid1_info *mirror = &conf->mirrors[disk];
722
723 best_disk = disk;
724 /*
725 * If buffered sequential IO size exceeds optimal
726 * iosize, check if there is idle disk. If yes, choose
727 * the idle disk. read_balance could already choose an
728 * idle disk before noticing it's a sequential IO in
729 * this disk. This doesn't matter because this disk
730 * will idle, next time it will be utilized after the
731 * first disk has IO size exceeds optimal iosize. In
732 * this way, iosize of the first disk will be optimal
733 * iosize at least. iosize of the second disk might be
734 * small, but not a big deal since when the second disk
735 * starts IO, the first disk is likely still busy.
736 */
737 if (nonrot && opt_iosize > 0 &&
738 mirror->seq_start != MaxSector &&
739 mirror->next_seq_sect > opt_iosize &&
740 mirror->next_seq_sect - opt_iosize >=
741 mirror->seq_start) {
742 choose_next_idle = 1;
743 continue;
744 }
745 break;
746 }
747
748 if (choose_next_idle)
749 continue;
750
751 if (min_pending > pending) {
752 min_pending = pending;
753 best_pending_disk = disk;
754 }
755
756 if (dist < best_dist) {
757 best_dist = dist;
758 best_dist_disk = disk;
759 }
760 }
761
762 /*
763 * If all disks are rotational, choose the closest disk. If any disk is
764 * non-rotational, choose the disk with less pending request even the
765 * disk is rotational, which might/might not be optimal for raids with
766 * mixed ratation/non-rotational disks depending on workload.
767 */
768 if (best_disk == -1) {
769 if (has_nonrot_disk || min_pending == 0)
770 best_disk = best_pending_disk;
771 else
772 best_disk = best_dist_disk;
773 }
774
775 if (best_disk >= 0) {
776 rdev = conf->mirrors[best_disk].rdev;
777 if (!rdev)
778 goto retry;
779 atomic_inc(&rdev->nr_pending);
780 sectors = best_good_sectors;
781
782 if (conf->mirrors[best_disk].next_seq_sect != this_sector)
783 conf->mirrors[best_disk].seq_start = this_sector;
784
785 conf->mirrors[best_disk].next_seq_sect = this_sector + sectors;
786 }
787 *max_sectors = sectors;
788
789 return best_disk;
790}
791
792static void wake_up_barrier(struct r1conf *conf)
793{
794 if (wq_has_sleeper(&conf->wait_barrier))
795 wake_up(&conf->wait_barrier);
796}
797
798static void flush_bio_list(struct r1conf *conf, struct bio *bio)
799{
800 /* flush any pending bitmap writes to disk before proceeding w/ I/O */
801 raid1_prepare_flush_writes(conf->mddev->bitmap);
802 wake_up_barrier(conf);
803
804 while (bio) { /* submit pending writes */
805 struct bio *next = bio->bi_next;
806
807 raid1_submit_write(bio);
808 bio = next;
809 cond_resched();
810 }
811}
812
813static void flush_pending_writes(struct r1conf *conf)
814{
815 /* Any writes that have been queued but are awaiting
816 * bitmap updates get flushed here.
817 */
818 spin_lock_irq(&conf->device_lock);
819
820 if (conf->pending_bio_list.head) {
821 struct blk_plug plug;
822 struct bio *bio;
823
824 bio = bio_list_get(&conf->pending_bio_list);
825 spin_unlock_irq(&conf->device_lock);
826
827 /*
828 * As this is called in a wait_event() loop (see freeze_array),
829 * current->state might be TASK_UNINTERRUPTIBLE which will
830 * cause a warning when we prepare to wait again. As it is
831 * rare that this path is taken, it is perfectly safe to force
832 * us to go around the wait_event() loop again, so the warning
833 * is a false-positive. Silence the warning by resetting
834 * thread state
835 */
836 __set_current_state(TASK_RUNNING);
837 blk_start_plug(&plug);
838 flush_bio_list(conf, bio);
839 blk_finish_plug(&plug);
840 } else
841 spin_unlock_irq(&conf->device_lock);
842}
843
844/* Barriers....
845 * Sometimes we need to suspend IO while we do something else,
846 * either some resync/recovery, or reconfigure the array.
847 * To do this we raise a 'barrier'.
848 * The 'barrier' is a counter that can be raised multiple times
849 * to count how many activities are happening which preclude
850 * normal IO.
851 * We can only raise the barrier if there is no pending IO.
852 * i.e. if nr_pending == 0.
853 * We choose only to raise the barrier if no-one is waiting for the
854 * barrier to go down. This means that as soon as an IO request
855 * is ready, no other operations which require a barrier will start
856 * until the IO request has had a chance.
857 *
858 * So: regular IO calls 'wait_barrier'. When that returns there
859 * is no backgroup IO happening, It must arrange to call
860 * allow_barrier when it has finished its IO.
861 * backgroup IO calls must call raise_barrier. Once that returns
862 * there is no normal IO happeing. It must arrange to call
863 * lower_barrier when the particular background IO completes.
864 *
865 * If resync/recovery is interrupted, returns -EINTR;
866 * Otherwise, returns 0.
867 */
868static int raise_barrier(struct r1conf *conf, sector_t sector_nr)
869{
870 int idx = sector_to_idx(sector_nr);
871
872 spin_lock_irq(&conf->resync_lock);
873
874 /* Wait until no block IO is waiting */
875 wait_event_lock_irq(conf->wait_barrier,
876 !atomic_read(&conf->nr_waiting[idx]),
877 conf->resync_lock);
878
879 /* block any new IO from starting */
880 atomic_inc(&conf->barrier[idx]);
881 /*
882 * In raise_barrier() we firstly increase conf->barrier[idx] then
883 * check conf->nr_pending[idx]. In _wait_barrier() we firstly
884 * increase conf->nr_pending[idx] then check conf->barrier[idx].
885 * A memory barrier here to make sure conf->nr_pending[idx] won't
886 * be fetched before conf->barrier[idx] is increased. Otherwise
887 * there will be a race between raise_barrier() and _wait_barrier().
888 */
889 smp_mb__after_atomic();
890
891 /* For these conditions we must wait:
892 * A: while the array is in frozen state
893 * B: while conf->nr_pending[idx] is not 0, meaning regular I/O
894 * existing in corresponding I/O barrier bucket.
895 * C: while conf->barrier[idx] >= RESYNC_DEPTH, meaning reaches
896 * max resync count which allowed on current I/O barrier bucket.
897 */
898 wait_event_lock_irq(conf->wait_barrier,
899 (!conf->array_frozen &&
900 !atomic_read(&conf->nr_pending[idx]) &&
901 atomic_read(&conf->barrier[idx]) < RESYNC_DEPTH) ||
902 test_bit(MD_RECOVERY_INTR, &conf->mddev->recovery),
903 conf->resync_lock);
904
905 if (test_bit(MD_RECOVERY_INTR, &conf->mddev->recovery)) {
906 atomic_dec(&conf->barrier[idx]);
907 spin_unlock_irq(&conf->resync_lock);
908 wake_up(&conf->wait_barrier);
909 return -EINTR;
910 }
911
912 atomic_inc(&conf->nr_sync_pending);
913 spin_unlock_irq(&conf->resync_lock);
914
915 return 0;
916}
917
918static void lower_barrier(struct r1conf *conf, sector_t sector_nr)
919{
920 int idx = sector_to_idx(sector_nr);
921
922 BUG_ON(atomic_read(&conf->barrier[idx]) <= 0);
923
924 atomic_dec(&conf->barrier[idx]);
925 atomic_dec(&conf->nr_sync_pending);
926 wake_up(&conf->wait_barrier);
927}
928
929static bool _wait_barrier(struct r1conf *conf, int idx, bool nowait)
930{
931 bool ret = true;
932
933 /*
934 * We need to increase conf->nr_pending[idx] very early here,
935 * then raise_barrier() can be blocked when it waits for
936 * conf->nr_pending[idx] to be 0. Then we can avoid holding
937 * conf->resync_lock when there is no barrier raised in same
938 * barrier unit bucket. Also if the array is frozen, I/O
939 * should be blocked until array is unfrozen.
940 */
941 atomic_inc(&conf->nr_pending[idx]);
942 /*
943 * In _wait_barrier() we firstly increase conf->nr_pending[idx], then
944 * check conf->barrier[idx]. In raise_barrier() we firstly increase
945 * conf->barrier[idx], then check conf->nr_pending[idx]. A memory
946 * barrier is necessary here to make sure conf->barrier[idx] won't be
947 * fetched before conf->nr_pending[idx] is increased. Otherwise there
948 * will be a race between _wait_barrier() and raise_barrier().
949 */
950 smp_mb__after_atomic();
951
952 /*
953 * Don't worry about checking two atomic_t variables at same time
954 * here. If during we check conf->barrier[idx], the array is
955 * frozen (conf->array_frozen is 1), and chonf->barrier[idx] is
956 * 0, it is safe to return and make the I/O continue. Because the
957 * array is frozen, all I/O returned here will eventually complete
958 * or be queued, no race will happen. See code comment in
959 * frozen_array().
960 */
961 if (!READ_ONCE(conf->array_frozen) &&
962 !atomic_read(&conf->barrier[idx]))
963 return ret;
964
965 /*
966 * After holding conf->resync_lock, conf->nr_pending[idx]
967 * should be decreased before waiting for barrier to drop.
968 * Otherwise, we may encounter a race condition because
969 * raise_barrer() might be waiting for conf->nr_pending[idx]
970 * to be 0 at same time.
971 */
972 spin_lock_irq(&conf->resync_lock);
973 atomic_inc(&conf->nr_waiting[idx]);
974 atomic_dec(&conf->nr_pending[idx]);
975 /*
976 * In case freeze_array() is waiting for
977 * get_unqueued_pending() == extra
978 */
979 wake_up_barrier(conf);
980 /* Wait for the barrier in same barrier unit bucket to drop. */
981
982 /* Return false when nowait flag is set */
983 if (nowait) {
984 ret = false;
985 } else {
986 wait_event_lock_irq(conf->wait_barrier,
987 !conf->array_frozen &&
988 !atomic_read(&conf->barrier[idx]),
989 conf->resync_lock);
990 atomic_inc(&conf->nr_pending[idx]);
991 }
992
993 atomic_dec(&conf->nr_waiting[idx]);
994 spin_unlock_irq(&conf->resync_lock);
995 return ret;
996}
997
998static bool wait_read_barrier(struct r1conf *conf, sector_t sector_nr, bool nowait)
999{
1000 int idx = sector_to_idx(sector_nr);
1001 bool ret = true;
1002
1003 /*
1004 * Very similar to _wait_barrier(). The difference is, for read
1005 * I/O we don't need wait for sync I/O, but if the whole array
1006 * is frozen, the read I/O still has to wait until the array is
1007 * unfrozen. Since there is no ordering requirement with
1008 * conf->barrier[idx] here, memory barrier is unnecessary as well.
1009 */
1010 atomic_inc(&conf->nr_pending[idx]);
1011
1012 if (!READ_ONCE(conf->array_frozen))
1013 return ret;
1014
1015 spin_lock_irq(&conf->resync_lock);
1016 atomic_inc(&conf->nr_waiting[idx]);
1017 atomic_dec(&conf->nr_pending[idx]);
1018 /*
1019 * In case freeze_array() is waiting for
1020 * get_unqueued_pending() == extra
1021 */
1022 wake_up_barrier(conf);
1023 /* Wait for array to be unfrozen */
1024
1025 /* Return false when nowait flag is set */
1026 if (nowait) {
1027 /* Return false when nowait flag is set */
1028 ret = false;
1029 } else {
1030 wait_event_lock_irq(conf->wait_barrier,
1031 !conf->array_frozen,
1032 conf->resync_lock);
1033 atomic_inc(&conf->nr_pending[idx]);
1034 }
1035
1036 atomic_dec(&conf->nr_waiting[idx]);
1037 spin_unlock_irq(&conf->resync_lock);
1038 return ret;
1039}
1040
1041static bool wait_barrier(struct r1conf *conf, sector_t sector_nr, bool nowait)
1042{
1043 int idx = sector_to_idx(sector_nr);
1044
1045 return _wait_barrier(conf, idx, nowait);
1046}
1047
1048static void _allow_barrier(struct r1conf *conf, int idx)
1049{
1050 atomic_dec(&conf->nr_pending[idx]);
1051 wake_up_barrier(conf);
1052}
1053
1054static void allow_barrier(struct r1conf *conf, sector_t sector_nr)
1055{
1056 int idx = sector_to_idx(sector_nr);
1057
1058 _allow_barrier(conf, idx);
1059}
1060
1061/* conf->resync_lock should be held */
1062static int get_unqueued_pending(struct r1conf *conf)
1063{
1064 int idx, ret;
1065
1066 ret = atomic_read(&conf->nr_sync_pending);
1067 for (idx = 0; idx < BARRIER_BUCKETS_NR; idx++)
1068 ret += atomic_read(&conf->nr_pending[idx]) -
1069 atomic_read(&conf->nr_queued[idx]);
1070
1071 return ret;
1072}
1073
1074static void freeze_array(struct r1conf *conf, int extra)
1075{
1076 /* Stop sync I/O and normal I/O and wait for everything to
1077 * go quiet.
1078 * This is called in two situations:
1079 * 1) management command handlers (reshape, remove disk, quiesce).
1080 * 2) one normal I/O request failed.
1081
1082 * After array_frozen is set to 1, new sync IO will be blocked at
1083 * raise_barrier(), and new normal I/O will blocked at _wait_barrier()
1084 * or wait_read_barrier(). The flying I/Os will either complete or be
1085 * queued. When everything goes quite, there are only queued I/Os left.
1086
1087 * Every flying I/O contributes to a conf->nr_pending[idx], idx is the
1088 * barrier bucket index which this I/O request hits. When all sync and
1089 * normal I/O are queued, sum of all conf->nr_pending[] will match sum
1090 * of all conf->nr_queued[]. But normal I/O failure is an exception,
1091 * in handle_read_error(), we may call freeze_array() before trying to
1092 * fix the read error. In this case, the error read I/O is not queued,
1093 * so get_unqueued_pending() == 1.
1094 *
1095 * Therefore before this function returns, we need to wait until
1096 * get_unqueued_pendings(conf) gets equal to extra. For
1097 * normal I/O context, extra is 1, in rested situations extra is 0.
1098 */
1099 spin_lock_irq(&conf->resync_lock);
1100 conf->array_frozen = 1;
1101 raid1_log(conf->mddev, "wait freeze");
1102 wait_event_lock_irq_cmd(
1103 conf->wait_barrier,
1104 get_unqueued_pending(conf) == extra,
1105 conf->resync_lock,
1106 flush_pending_writes(conf));
1107 spin_unlock_irq(&conf->resync_lock);
1108}
1109static void unfreeze_array(struct r1conf *conf)
1110{
1111 /* reverse the effect of the freeze */
1112 spin_lock_irq(&conf->resync_lock);
1113 conf->array_frozen = 0;
1114 spin_unlock_irq(&conf->resync_lock);
1115 wake_up(&conf->wait_barrier);
1116}
1117
1118static void alloc_behind_master_bio(struct r1bio *r1_bio,
1119 struct bio *bio)
1120{
1121 int size = bio->bi_iter.bi_size;
1122 unsigned vcnt = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
1123 int i = 0;
1124 struct bio *behind_bio = NULL;
1125
1126 behind_bio = bio_alloc_bioset(NULL, vcnt, 0, GFP_NOIO,
1127 &r1_bio->mddev->bio_set);
1128
1129 /* discard op, we don't support writezero/writesame yet */
1130 if (!bio_has_data(bio)) {
1131 behind_bio->bi_iter.bi_size = size;
1132 goto skip_copy;
1133 }
1134
1135 while (i < vcnt && size) {
1136 struct page *page;
1137 int len = min_t(int, PAGE_SIZE, size);
1138
1139 page = alloc_page(GFP_NOIO);
1140 if (unlikely(!page))
1141 goto free_pages;
1142
1143 if (!bio_add_page(behind_bio, page, len, 0)) {
1144 put_page(page);
1145 goto free_pages;
1146 }
1147
1148 size -= len;
1149 i++;
1150 }
1151
1152 bio_copy_data(behind_bio, bio);
1153skip_copy:
1154 r1_bio->behind_master_bio = behind_bio;
1155 set_bit(R1BIO_BehindIO, &r1_bio->state);
1156
1157 return;
1158
1159free_pages:
1160 pr_debug("%dB behind alloc failed, doing sync I/O\n",
1161 bio->bi_iter.bi_size);
1162 bio_free_pages(behind_bio);
1163 bio_put(behind_bio);
1164}
1165
1166static void raid1_unplug(struct blk_plug_cb *cb, bool from_schedule)
1167{
1168 struct raid1_plug_cb *plug = container_of(cb, struct raid1_plug_cb,
1169 cb);
1170 struct mddev *mddev = plug->cb.data;
1171 struct r1conf *conf = mddev->private;
1172 struct bio *bio;
1173
1174 if (from_schedule) {
1175 spin_lock_irq(&conf->device_lock);
1176 bio_list_merge(&conf->pending_bio_list, &plug->pending);
1177 spin_unlock_irq(&conf->device_lock);
1178 wake_up_barrier(conf);
1179 md_wakeup_thread(mddev->thread);
1180 kfree(plug);
1181 return;
1182 }
1183
1184 /* we aren't scheduling, so we can do the write-out directly. */
1185 bio = bio_list_get(&plug->pending);
1186 flush_bio_list(conf, bio);
1187 kfree(plug);
1188}
1189
1190static void init_r1bio(struct r1bio *r1_bio, struct mddev *mddev, struct bio *bio)
1191{
1192 r1_bio->master_bio = bio;
1193 r1_bio->sectors = bio_sectors(bio);
1194 r1_bio->state = 0;
1195 r1_bio->mddev = mddev;
1196 r1_bio->sector = bio->bi_iter.bi_sector;
1197}
1198
1199static inline struct r1bio *
1200alloc_r1bio(struct mddev *mddev, struct bio *bio)
1201{
1202 struct r1conf *conf = mddev->private;
1203 struct r1bio *r1_bio;
1204
1205 r1_bio = mempool_alloc(&conf->r1bio_pool, GFP_NOIO);
1206 /* Ensure no bio records IO_BLOCKED */
1207 memset(r1_bio->bios, 0, conf->raid_disks * sizeof(r1_bio->bios[0]));
1208 init_r1bio(r1_bio, mddev, bio);
1209 return r1_bio;
1210}
1211
1212static void raid1_read_request(struct mddev *mddev, struct bio *bio,
1213 int max_read_sectors, struct r1bio *r1_bio)
1214{
1215 struct r1conf *conf = mddev->private;
1216 struct raid1_info *mirror;
1217 struct bio *read_bio;
1218 struct bitmap *bitmap = mddev->bitmap;
1219 const enum req_op op = bio_op(bio);
1220 const blk_opf_t do_sync = bio->bi_opf & REQ_SYNC;
1221 int max_sectors;
1222 int rdisk;
1223 bool r1bio_existed = !!r1_bio;
1224 char b[BDEVNAME_SIZE];
1225
1226 /*
1227 * If r1_bio is set, we are blocking the raid1d thread
1228 * so there is a tiny risk of deadlock. So ask for
1229 * emergency memory if needed.
1230 */
1231 gfp_t gfp = r1_bio ? (GFP_NOIO | __GFP_HIGH) : GFP_NOIO;
1232
1233 if (r1bio_existed) {
1234 /* Need to get the block device name carefully */
1235 struct md_rdev *rdev = conf->mirrors[r1_bio->read_disk].rdev;
1236
1237 if (rdev)
1238 snprintf(b, sizeof(b), "%pg", rdev->bdev);
1239 else
1240 strcpy(b, "???");
1241 }
1242
1243 /*
1244 * Still need barrier for READ in case that whole
1245 * array is frozen.
1246 */
1247 if (!wait_read_barrier(conf, bio->bi_iter.bi_sector,
1248 bio->bi_opf & REQ_NOWAIT)) {
1249 bio_wouldblock_error(bio);
1250 return;
1251 }
1252
1253 if (!r1_bio)
1254 r1_bio = alloc_r1bio(mddev, bio);
1255 else
1256 init_r1bio(r1_bio, mddev, bio);
1257 r1_bio->sectors = max_read_sectors;
1258
1259 /*
1260 * make_request() can abort the operation when read-ahead is being
1261 * used and no empty request is available.
1262 */
1263 rdisk = read_balance(conf, r1_bio, &max_sectors);
1264
1265 if (rdisk < 0) {
1266 /* couldn't find anywhere to read from */
1267 if (r1bio_existed) {
1268 pr_crit_ratelimited("md/raid1:%s: %s: unrecoverable I/O read error for block %llu\n",
1269 mdname(mddev),
1270 b,
1271 (unsigned long long)r1_bio->sector);
1272 }
1273 raid_end_bio_io(r1_bio);
1274 return;
1275 }
1276 mirror = conf->mirrors + rdisk;
1277
1278 if (r1bio_existed)
1279 pr_info_ratelimited("md/raid1:%s: redirecting sector %llu to other mirror: %pg\n",
1280 mdname(mddev),
1281 (unsigned long long)r1_bio->sector,
1282 mirror->rdev->bdev);
1283
1284 if (test_bit(WriteMostly, &mirror->rdev->flags) &&
1285 bitmap) {
1286 /*
1287 * Reading from a write-mostly device must take care not to
1288 * over-take any writes that are 'behind'
1289 */
1290 raid1_log(mddev, "wait behind writes");
1291 wait_event(bitmap->behind_wait,
1292 atomic_read(&bitmap->behind_writes) == 0);
1293 }
1294
1295 if (max_sectors < bio_sectors(bio)) {
1296 struct bio *split = bio_split(bio, max_sectors,
1297 gfp, &conf->bio_split);
1298 bio_chain(split, bio);
1299 submit_bio_noacct(bio);
1300 bio = split;
1301 r1_bio->master_bio = bio;
1302 r1_bio->sectors = max_sectors;
1303 }
1304
1305 r1_bio->read_disk = rdisk;
1306 if (!r1bio_existed) {
1307 md_account_bio(mddev, &bio);
1308 r1_bio->master_bio = bio;
1309 }
1310 read_bio = bio_alloc_clone(mirror->rdev->bdev, bio, gfp,
1311 &mddev->bio_set);
1312
1313 r1_bio->bios[rdisk] = read_bio;
1314
1315 read_bio->bi_iter.bi_sector = r1_bio->sector +
1316 mirror->rdev->data_offset;
1317 read_bio->bi_end_io = raid1_end_read_request;
1318 read_bio->bi_opf = op | do_sync;
1319 if (test_bit(FailFast, &mirror->rdev->flags) &&
1320 test_bit(R1BIO_FailFast, &r1_bio->state))
1321 read_bio->bi_opf |= MD_FAILFAST;
1322 read_bio->bi_private = r1_bio;
1323
1324 if (mddev->gendisk)
1325 trace_block_bio_remap(read_bio, disk_devt(mddev->gendisk),
1326 r1_bio->sector);
1327
1328 submit_bio_noacct(read_bio);
1329}
1330
1331static void raid1_write_request(struct mddev *mddev, struct bio *bio,
1332 int max_write_sectors)
1333{
1334 struct r1conf *conf = mddev->private;
1335 struct r1bio *r1_bio;
1336 int i, disks;
1337 struct bitmap *bitmap = mddev->bitmap;
1338 unsigned long flags;
1339 struct md_rdev *blocked_rdev;
1340 int first_clone;
1341 int max_sectors;
1342 bool write_behind = false;
1343 bool is_discard = (bio_op(bio) == REQ_OP_DISCARD);
1344
1345 if (mddev_is_clustered(mddev) &&
1346 md_cluster_ops->area_resyncing(mddev, WRITE,
1347 bio->bi_iter.bi_sector, bio_end_sector(bio))) {
1348
1349 DEFINE_WAIT(w);
1350 if (bio->bi_opf & REQ_NOWAIT) {
1351 bio_wouldblock_error(bio);
1352 return;
1353 }
1354 for (;;) {
1355 prepare_to_wait(&conf->wait_barrier,
1356 &w, TASK_IDLE);
1357 if (!md_cluster_ops->area_resyncing(mddev, WRITE,
1358 bio->bi_iter.bi_sector,
1359 bio_end_sector(bio)))
1360 break;
1361 schedule();
1362 }
1363 finish_wait(&conf->wait_barrier, &w);
1364 }
1365
1366 /*
1367 * Register the new request and wait if the reconstruction
1368 * thread has put up a bar for new requests.
1369 * Continue immediately if no resync is active currently.
1370 */
1371 if (!wait_barrier(conf, bio->bi_iter.bi_sector,
1372 bio->bi_opf & REQ_NOWAIT)) {
1373 bio_wouldblock_error(bio);
1374 return;
1375 }
1376
1377 retry_write:
1378 r1_bio = alloc_r1bio(mddev, bio);
1379 r1_bio->sectors = max_write_sectors;
1380
1381 /* first select target devices under rcu_lock and
1382 * inc refcount on their rdev. Record them by setting
1383 * bios[x] to bio
1384 * If there are known/acknowledged bad blocks on any device on
1385 * which we have seen a write error, we want to avoid writing those
1386 * blocks.
1387 * This potentially requires several writes to write around
1388 * the bad blocks. Each set of writes gets it's own r1bio
1389 * with a set of bios attached.
1390 */
1391
1392 disks = conf->raid_disks * 2;
1393 blocked_rdev = NULL;
1394 max_sectors = r1_bio->sectors;
1395 for (i = 0; i < disks; i++) {
1396 struct md_rdev *rdev = conf->mirrors[i].rdev;
1397
1398 /*
1399 * The write-behind io is only attempted on drives marked as
1400 * write-mostly, which means we could allocate write behind
1401 * bio later.
1402 */
1403 if (!is_discard && rdev && test_bit(WriteMostly, &rdev->flags))
1404 write_behind = true;
1405
1406 if (rdev && unlikely(test_bit(Blocked, &rdev->flags))) {
1407 atomic_inc(&rdev->nr_pending);
1408 blocked_rdev = rdev;
1409 break;
1410 }
1411 r1_bio->bios[i] = NULL;
1412 if (!rdev || test_bit(Faulty, &rdev->flags)) {
1413 if (i < conf->raid_disks)
1414 set_bit(R1BIO_Degraded, &r1_bio->state);
1415 continue;
1416 }
1417
1418 atomic_inc(&rdev->nr_pending);
1419 if (test_bit(WriteErrorSeen, &rdev->flags)) {
1420 sector_t first_bad;
1421 int bad_sectors;
1422 int is_bad;
1423
1424 is_bad = is_badblock(rdev, r1_bio->sector, max_sectors,
1425 &first_bad, &bad_sectors);
1426 if (is_bad < 0) {
1427 /* mustn't write here until the bad block is
1428 * acknowledged*/
1429 set_bit(BlockedBadBlocks, &rdev->flags);
1430 blocked_rdev = rdev;
1431 break;
1432 }
1433 if (is_bad && first_bad <= r1_bio->sector) {
1434 /* Cannot write here at all */
1435 bad_sectors -= (r1_bio->sector - first_bad);
1436 if (bad_sectors < max_sectors)
1437 /* mustn't write more than bad_sectors
1438 * to other devices yet
1439 */
1440 max_sectors = bad_sectors;
1441 rdev_dec_pending(rdev, mddev);
1442 /* We don't set R1BIO_Degraded as that
1443 * only applies if the disk is
1444 * missing, so it might be re-added,
1445 * and we want to know to recover this
1446 * chunk.
1447 * In this case the device is here,
1448 * and the fact that this chunk is not
1449 * in-sync is recorded in the bad
1450 * block log
1451 */
1452 continue;
1453 }
1454 if (is_bad) {
1455 int good_sectors = first_bad - r1_bio->sector;
1456 if (good_sectors < max_sectors)
1457 max_sectors = good_sectors;
1458 }
1459 }
1460 r1_bio->bios[i] = bio;
1461 }
1462
1463 if (unlikely(blocked_rdev)) {
1464 /* Wait for this device to become unblocked */
1465 int j;
1466
1467 for (j = 0; j < i; j++)
1468 if (r1_bio->bios[j])
1469 rdev_dec_pending(conf->mirrors[j].rdev, mddev);
1470 free_r1bio(r1_bio);
1471 allow_barrier(conf, bio->bi_iter.bi_sector);
1472
1473 if (bio->bi_opf & REQ_NOWAIT) {
1474 bio_wouldblock_error(bio);
1475 return;
1476 }
1477 raid1_log(mddev, "wait rdev %d blocked", blocked_rdev->raid_disk);
1478 md_wait_for_blocked_rdev(blocked_rdev, mddev);
1479 wait_barrier(conf, bio->bi_iter.bi_sector, false);
1480 goto retry_write;
1481 }
1482
1483 /*
1484 * When using a bitmap, we may call alloc_behind_master_bio below.
1485 * alloc_behind_master_bio allocates a copy of the data payload a page
1486 * at a time and thus needs a new bio that can fit the whole payload
1487 * this bio in page sized chunks.
1488 */
1489 if (write_behind && bitmap)
1490 max_sectors = min_t(int, max_sectors,
1491 BIO_MAX_VECS * (PAGE_SIZE >> 9));
1492 if (max_sectors < bio_sectors(bio)) {
1493 struct bio *split = bio_split(bio, max_sectors,
1494 GFP_NOIO, &conf->bio_split);
1495 bio_chain(split, bio);
1496 submit_bio_noacct(bio);
1497 bio = split;
1498 r1_bio->master_bio = bio;
1499 r1_bio->sectors = max_sectors;
1500 }
1501
1502 md_account_bio(mddev, &bio);
1503 r1_bio->master_bio = bio;
1504 atomic_set(&r1_bio->remaining, 1);
1505 atomic_set(&r1_bio->behind_remaining, 0);
1506
1507 first_clone = 1;
1508
1509 for (i = 0; i < disks; i++) {
1510 struct bio *mbio = NULL;
1511 struct md_rdev *rdev = conf->mirrors[i].rdev;
1512 if (!r1_bio->bios[i])
1513 continue;
1514
1515 if (first_clone) {
1516 /* do behind I/O ?
1517 * Not if there are too many, or cannot
1518 * allocate memory, or a reader on WriteMostly
1519 * is waiting for behind writes to flush */
1520 if (bitmap && write_behind &&
1521 (atomic_read(&bitmap->behind_writes)
1522 < mddev->bitmap_info.max_write_behind) &&
1523 !waitqueue_active(&bitmap->behind_wait)) {
1524 alloc_behind_master_bio(r1_bio, bio);
1525 }
1526
1527 md_bitmap_startwrite(bitmap, r1_bio->sector, r1_bio->sectors,
1528 test_bit(R1BIO_BehindIO, &r1_bio->state));
1529 first_clone = 0;
1530 }
1531
1532 if (r1_bio->behind_master_bio) {
1533 mbio = bio_alloc_clone(rdev->bdev,
1534 r1_bio->behind_master_bio,
1535 GFP_NOIO, &mddev->bio_set);
1536 if (test_bit(CollisionCheck, &rdev->flags))
1537 wait_for_serialization(rdev, r1_bio);
1538 if (test_bit(WriteMostly, &rdev->flags))
1539 atomic_inc(&r1_bio->behind_remaining);
1540 } else {
1541 mbio = bio_alloc_clone(rdev->bdev, bio, GFP_NOIO,
1542 &mddev->bio_set);
1543
1544 if (mddev->serialize_policy)
1545 wait_for_serialization(rdev, r1_bio);
1546 }
1547
1548 r1_bio->bios[i] = mbio;
1549
1550 mbio->bi_iter.bi_sector = (r1_bio->sector + rdev->data_offset);
1551 mbio->bi_end_io = raid1_end_write_request;
1552 mbio->bi_opf = bio_op(bio) | (bio->bi_opf & (REQ_SYNC | REQ_FUA));
1553 if (test_bit(FailFast, &rdev->flags) &&
1554 !test_bit(WriteMostly, &rdev->flags) &&
1555 conf->raid_disks - mddev->degraded > 1)
1556 mbio->bi_opf |= MD_FAILFAST;
1557 mbio->bi_private = r1_bio;
1558
1559 atomic_inc(&r1_bio->remaining);
1560
1561 if (mddev->gendisk)
1562 trace_block_bio_remap(mbio, disk_devt(mddev->gendisk),
1563 r1_bio->sector);
1564 /* flush_pending_writes() needs access to the rdev so...*/
1565 mbio->bi_bdev = (void *)rdev;
1566 if (!raid1_add_bio_to_plug(mddev, mbio, raid1_unplug, disks)) {
1567 spin_lock_irqsave(&conf->device_lock, flags);
1568 bio_list_add(&conf->pending_bio_list, mbio);
1569 spin_unlock_irqrestore(&conf->device_lock, flags);
1570 md_wakeup_thread(mddev->thread);
1571 }
1572 }
1573
1574 r1_bio_write_done(r1_bio);
1575
1576 /* In case raid1d snuck in to freeze_array */
1577 wake_up_barrier(conf);
1578}
1579
1580static bool raid1_make_request(struct mddev *mddev, struct bio *bio)
1581{
1582 sector_t sectors;
1583
1584 if (unlikely(bio->bi_opf & REQ_PREFLUSH)
1585 && md_flush_request(mddev, bio))
1586 return true;
1587
1588 /*
1589 * There is a limit to the maximum size, but
1590 * the read/write handler might find a lower limit
1591 * due to bad blocks. To avoid multiple splits,
1592 * we pass the maximum number of sectors down
1593 * and let the lower level perform the split.
1594 */
1595 sectors = align_to_barrier_unit_end(
1596 bio->bi_iter.bi_sector, bio_sectors(bio));
1597
1598 if (bio_data_dir(bio) == READ)
1599 raid1_read_request(mddev, bio, sectors, NULL);
1600 else {
1601 if (!md_write_start(mddev,bio))
1602 return false;
1603 raid1_write_request(mddev, bio, sectors);
1604 }
1605 return true;
1606}
1607
1608static void raid1_status(struct seq_file *seq, struct mddev *mddev)
1609{
1610 struct r1conf *conf = mddev->private;
1611 int i;
1612
1613 lockdep_assert_held(&mddev->lock);
1614
1615 seq_printf(seq, " [%d/%d] [", conf->raid_disks,
1616 conf->raid_disks - mddev->degraded);
1617 for (i = 0; i < conf->raid_disks; i++) {
1618 struct md_rdev *rdev = READ_ONCE(conf->mirrors[i].rdev);
1619
1620 seq_printf(seq, "%s",
1621 rdev && test_bit(In_sync, &rdev->flags) ? "U" : "_");
1622 }
1623 seq_printf(seq, "]");
1624}
1625
1626/**
1627 * raid1_error() - RAID1 error handler.
1628 * @mddev: affected md device.
1629 * @rdev: member device to fail.
1630 *
1631 * The routine acknowledges &rdev failure and determines new @mddev state.
1632 * If it failed, then:
1633 * - &MD_BROKEN flag is set in &mddev->flags.
1634 * - recovery is disabled.
1635 * Otherwise, it must be degraded:
1636 * - recovery is interrupted.
1637 * - &mddev->degraded is bumped.
1638 *
1639 * @rdev is marked as &Faulty excluding case when array is failed and
1640 * &mddev->fail_last_dev is off.
1641 */
1642static void raid1_error(struct mddev *mddev, struct md_rdev *rdev)
1643{
1644 struct r1conf *conf = mddev->private;
1645 unsigned long flags;
1646
1647 spin_lock_irqsave(&conf->device_lock, flags);
1648
1649 if (test_bit(In_sync, &rdev->flags) &&
1650 (conf->raid_disks - mddev->degraded) == 1) {
1651 set_bit(MD_BROKEN, &mddev->flags);
1652
1653 if (!mddev->fail_last_dev) {
1654 conf->recovery_disabled = mddev->recovery_disabled;
1655 spin_unlock_irqrestore(&conf->device_lock, flags);
1656 return;
1657 }
1658 }
1659 set_bit(Blocked, &rdev->flags);
1660 if (test_and_clear_bit(In_sync, &rdev->flags))
1661 mddev->degraded++;
1662 set_bit(Faulty, &rdev->flags);
1663 spin_unlock_irqrestore(&conf->device_lock, flags);
1664 /*
1665 * if recovery is running, make sure it aborts.
1666 */
1667 set_bit(MD_RECOVERY_INTR, &mddev->recovery);
1668 set_mask_bits(&mddev->sb_flags, 0,
1669 BIT(MD_SB_CHANGE_DEVS) | BIT(MD_SB_CHANGE_PENDING));
1670 pr_crit("md/raid1:%s: Disk failure on %pg, disabling device.\n"
1671 "md/raid1:%s: Operation continuing on %d devices.\n",
1672 mdname(mddev), rdev->bdev,
1673 mdname(mddev), conf->raid_disks - mddev->degraded);
1674}
1675
1676static void print_conf(struct r1conf *conf)
1677{
1678 int i;
1679
1680 pr_debug("RAID1 conf printout:\n");
1681 if (!conf) {
1682 pr_debug("(!conf)\n");
1683 return;
1684 }
1685 pr_debug(" --- wd:%d rd:%d\n", conf->raid_disks - conf->mddev->degraded,
1686 conf->raid_disks);
1687
1688 lockdep_assert_held(&conf->mddev->reconfig_mutex);
1689 for (i = 0; i < conf->raid_disks; i++) {
1690 struct md_rdev *rdev = conf->mirrors[i].rdev;
1691 if (rdev)
1692 pr_debug(" disk %d, wo:%d, o:%d, dev:%pg\n",
1693 i, !test_bit(In_sync, &rdev->flags),
1694 !test_bit(Faulty, &rdev->flags),
1695 rdev->bdev);
1696 }
1697}
1698
1699static void close_sync(struct r1conf *conf)
1700{
1701 int idx;
1702
1703 for (idx = 0; idx < BARRIER_BUCKETS_NR; idx++) {
1704 _wait_barrier(conf, idx, false);
1705 _allow_barrier(conf, idx);
1706 }
1707
1708 mempool_exit(&conf->r1buf_pool);
1709}
1710
1711static int raid1_spare_active(struct mddev *mddev)
1712{
1713 int i;
1714 struct r1conf *conf = mddev->private;
1715 int count = 0;
1716 unsigned long flags;
1717
1718 /*
1719 * Find all failed disks within the RAID1 configuration
1720 * and mark them readable.
1721 * Called under mddev lock, so rcu protection not needed.
1722 * device_lock used to avoid races with raid1_end_read_request
1723 * which expects 'In_sync' flags and ->degraded to be consistent.
1724 */
1725 spin_lock_irqsave(&conf->device_lock, flags);
1726 for (i = 0; i < conf->raid_disks; i++) {
1727 struct md_rdev *rdev = conf->mirrors[i].rdev;
1728 struct md_rdev *repl = conf->mirrors[conf->raid_disks + i].rdev;
1729 if (repl
1730 && !test_bit(Candidate, &repl->flags)
1731 && repl->recovery_offset == MaxSector
1732 && !test_bit(Faulty, &repl->flags)
1733 && !test_and_set_bit(In_sync, &repl->flags)) {
1734 /* replacement has just become active */
1735 if (!rdev ||
1736 !test_and_clear_bit(In_sync, &rdev->flags))
1737 count++;
1738 if (rdev) {
1739 /* Replaced device not technically
1740 * faulty, but we need to be sure
1741 * it gets removed and never re-added
1742 */
1743 set_bit(Faulty, &rdev->flags);
1744 sysfs_notify_dirent_safe(
1745 rdev->sysfs_state);
1746 }
1747 }
1748 if (rdev
1749 && rdev->recovery_offset == MaxSector
1750 && !test_bit(Faulty, &rdev->flags)
1751 && !test_and_set_bit(In_sync, &rdev->flags)) {
1752 count++;
1753 sysfs_notify_dirent_safe(rdev->sysfs_state);
1754 }
1755 }
1756 mddev->degraded -= count;
1757 spin_unlock_irqrestore(&conf->device_lock, flags);
1758
1759 print_conf(conf);
1760 return count;
1761}
1762
1763static int raid1_add_disk(struct mddev *mddev, struct md_rdev *rdev)
1764{
1765 struct r1conf *conf = mddev->private;
1766 int err = -EEXIST;
1767 int mirror = 0, repl_slot = -1;
1768 struct raid1_info *p;
1769 int first = 0;
1770 int last = conf->raid_disks - 1;
1771
1772 if (mddev->recovery_disabled == conf->recovery_disabled)
1773 return -EBUSY;
1774
1775 if (md_integrity_add_rdev(rdev, mddev))
1776 return -ENXIO;
1777
1778 if (rdev->raid_disk >= 0)
1779 first = last = rdev->raid_disk;
1780
1781 /*
1782 * find the disk ... but prefer rdev->saved_raid_disk
1783 * if possible.
1784 */
1785 if (rdev->saved_raid_disk >= 0 &&
1786 rdev->saved_raid_disk >= first &&
1787 rdev->saved_raid_disk < conf->raid_disks &&
1788 conf->mirrors[rdev->saved_raid_disk].rdev == NULL)
1789 first = last = rdev->saved_raid_disk;
1790
1791 for (mirror = first; mirror <= last; mirror++) {
1792 p = conf->mirrors + mirror;
1793 if (!p->rdev) {
1794 if (mddev->gendisk)
1795 disk_stack_limits(mddev->gendisk, rdev->bdev,
1796 rdev->data_offset << 9);
1797
1798 p->head_position = 0;
1799 rdev->raid_disk = mirror;
1800 err = 0;
1801 /* As all devices are equivalent, we don't need a full recovery
1802 * if this was recently any drive of the array
1803 */
1804 if (rdev->saved_raid_disk < 0)
1805 conf->fullsync = 1;
1806 WRITE_ONCE(p->rdev, rdev);
1807 break;
1808 }
1809 if (test_bit(WantReplacement, &p->rdev->flags) &&
1810 p[conf->raid_disks].rdev == NULL && repl_slot < 0)
1811 repl_slot = mirror;
1812 }
1813
1814 if (err && repl_slot >= 0) {
1815 /* Add this device as a replacement */
1816 p = conf->mirrors + repl_slot;
1817 clear_bit(In_sync, &rdev->flags);
1818 set_bit(Replacement, &rdev->flags);
1819 rdev->raid_disk = repl_slot;
1820 err = 0;
1821 conf->fullsync = 1;
1822 WRITE_ONCE(p[conf->raid_disks].rdev, rdev);
1823 }
1824
1825 print_conf(conf);
1826 return err;
1827}
1828
1829static int raid1_remove_disk(struct mddev *mddev, struct md_rdev *rdev)
1830{
1831 struct r1conf *conf = mddev->private;
1832 int err = 0;
1833 int number = rdev->raid_disk;
1834 struct raid1_info *p = conf->mirrors + number;
1835
1836 if (unlikely(number >= conf->raid_disks))
1837 goto abort;
1838
1839 if (rdev != p->rdev)
1840 p = conf->mirrors + conf->raid_disks + number;
1841
1842 print_conf(conf);
1843 if (rdev == p->rdev) {
1844 if (test_bit(In_sync, &rdev->flags) ||
1845 atomic_read(&rdev->nr_pending)) {
1846 err = -EBUSY;
1847 goto abort;
1848 }
1849 /* Only remove non-faulty devices if recovery
1850 * is not possible.
1851 */
1852 if (!test_bit(Faulty, &rdev->flags) &&
1853 mddev->recovery_disabled != conf->recovery_disabled &&
1854 mddev->degraded < conf->raid_disks) {
1855 err = -EBUSY;
1856 goto abort;
1857 }
1858 WRITE_ONCE(p->rdev, NULL);
1859 if (conf->mirrors[conf->raid_disks + number].rdev) {
1860 /* We just removed a device that is being replaced.
1861 * Move down the replacement. We drain all IO before
1862 * doing this to avoid confusion.
1863 */
1864 struct md_rdev *repl =
1865 conf->mirrors[conf->raid_disks + number].rdev;
1866 freeze_array(conf, 0);
1867 if (atomic_read(&repl->nr_pending)) {
1868 /* It means that some queued IO of retry_list
1869 * hold repl. Thus, we cannot set replacement
1870 * as NULL, avoiding rdev NULL pointer
1871 * dereference in sync_request_write and
1872 * handle_write_finished.
1873 */
1874 err = -EBUSY;
1875 unfreeze_array(conf);
1876 goto abort;
1877 }
1878 clear_bit(Replacement, &repl->flags);
1879 WRITE_ONCE(p->rdev, repl);
1880 conf->mirrors[conf->raid_disks + number].rdev = NULL;
1881 unfreeze_array(conf);
1882 }
1883
1884 clear_bit(WantReplacement, &rdev->flags);
1885 err = md_integrity_register(mddev);
1886 }
1887abort:
1888
1889 print_conf(conf);
1890 return err;
1891}
1892
1893static void end_sync_read(struct bio *bio)
1894{
1895 struct r1bio *r1_bio = get_resync_r1bio(bio);
1896
1897 update_head_pos(r1_bio->read_disk, r1_bio);
1898
1899 /*
1900 * we have read a block, now it needs to be re-written,
1901 * or re-read if the read failed.
1902 * We don't do much here, just schedule handling by raid1d
1903 */
1904 if (!bio->bi_status)
1905 set_bit(R1BIO_Uptodate, &r1_bio->state);
1906
1907 if (atomic_dec_and_test(&r1_bio->remaining))
1908 reschedule_retry(r1_bio);
1909}
1910
1911static void abort_sync_write(struct mddev *mddev, struct r1bio *r1_bio)
1912{
1913 sector_t sync_blocks = 0;
1914 sector_t s = r1_bio->sector;
1915 long sectors_to_go = r1_bio->sectors;
1916
1917 /* make sure these bits don't get cleared. */
1918 do {
1919 md_bitmap_end_sync(mddev->bitmap, s, &sync_blocks, 1);
1920 s += sync_blocks;
1921 sectors_to_go -= sync_blocks;
1922 } while (sectors_to_go > 0);
1923}
1924
1925static void put_sync_write_buf(struct r1bio *r1_bio, int uptodate)
1926{
1927 if (atomic_dec_and_test(&r1_bio->remaining)) {
1928 struct mddev *mddev = r1_bio->mddev;
1929 int s = r1_bio->sectors;
1930
1931 if (test_bit(R1BIO_MadeGood, &r1_bio->state) ||
1932 test_bit(R1BIO_WriteError, &r1_bio->state))
1933 reschedule_retry(r1_bio);
1934 else {
1935 put_buf(r1_bio);
1936 md_done_sync(mddev, s, uptodate);
1937 }
1938 }
1939}
1940
1941static void end_sync_write(struct bio *bio)
1942{
1943 int uptodate = !bio->bi_status;
1944 struct r1bio *r1_bio = get_resync_r1bio(bio);
1945 struct mddev *mddev = r1_bio->mddev;
1946 struct r1conf *conf = mddev->private;
1947 sector_t first_bad;
1948 int bad_sectors;
1949 struct md_rdev *rdev = conf->mirrors[find_bio_disk(r1_bio, bio)].rdev;
1950
1951 if (!uptodate) {
1952 abort_sync_write(mddev, r1_bio);
1953 set_bit(WriteErrorSeen, &rdev->flags);
1954 if (!test_and_set_bit(WantReplacement, &rdev->flags))
1955 set_bit(MD_RECOVERY_NEEDED, &
1956 mddev->recovery);
1957 set_bit(R1BIO_WriteError, &r1_bio->state);
1958 } else if (is_badblock(rdev, r1_bio->sector, r1_bio->sectors,
1959 &first_bad, &bad_sectors) &&
1960 !is_badblock(conf->mirrors[r1_bio->read_disk].rdev,
1961 r1_bio->sector,
1962 r1_bio->sectors,
1963 &first_bad, &bad_sectors)
1964 )
1965 set_bit(R1BIO_MadeGood, &r1_bio->state);
1966
1967 put_sync_write_buf(r1_bio, uptodate);
1968}
1969
1970static int r1_sync_page_io(struct md_rdev *rdev, sector_t sector,
1971 int sectors, struct page *page, blk_opf_t rw)
1972{
1973 if (sync_page_io(rdev, sector, sectors << 9, page, rw, false))
1974 /* success */
1975 return 1;
1976 if (rw == REQ_OP_WRITE) {
1977 set_bit(WriteErrorSeen, &rdev->flags);
1978 if (!test_and_set_bit(WantReplacement,
1979 &rdev->flags))
1980 set_bit(MD_RECOVERY_NEEDED, &
1981 rdev->mddev->recovery);
1982 }
1983 /* need to record an error - either for the block or the device */
1984 if (!rdev_set_badblocks(rdev, sector, sectors, 0))
1985 md_error(rdev->mddev, rdev);
1986 return 0;
1987}
1988
1989static int fix_sync_read_error(struct r1bio *r1_bio)
1990{
1991 /* Try some synchronous reads of other devices to get
1992 * good data, much like with normal read errors. Only
1993 * read into the pages we already have so we don't
1994 * need to re-issue the read request.
1995 * We don't need to freeze the array, because being in an
1996 * active sync request, there is no normal IO, and
1997 * no overlapping syncs.
1998 * We don't need to check is_badblock() again as we
1999 * made sure that anything with a bad block in range
2000 * will have bi_end_io clear.
2001 */
2002 struct mddev *mddev = r1_bio->mddev;
2003 struct r1conf *conf = mddev->private;
2004 struct bio *bio = r1_bio->bios[r1_bio->read_disk];
2005 struct page **pages = get_resync_pages(bio)->pages;
2006 sector_t sect = r1_bio->sector;
2007 int sectors = r1_bio->sectors;
2008 int idx = 0;
2009 struct md_rdev *rdev;
2010
2011 rdev = conf->mirrors[r1_bio->read_disk].rdev;
2012 if (test_bit(FailFast, &rdev->flags)) {
2013 /* Don't try recovering from here - just fail it
2014 * ... unless it is the last working device of course */
2015 md_error(mddev, rdev);
2016 if (test_bit(Faulty, &rdev->flags))
2017 /* Don't try to read from here, but make sure
2018 * put_buf does it's thing
2019 */
2020 bio->bi_end_io = end_sync_write;
2021 }
2022
2023 while(sectors) {
2024 int s = sectors;
2025 int d = r1_bio->read_disk;
2026 int success = 0;
2027 int start;
2028
2029 if (s > (PAGE_SIZE>>9))
2030 s = PAGE_SIZE >> 9;
2031 do {
2032 if (r1_bio->bios[d]->bi_end_io == end_sync_read) {
2033 /* No rcu protection needed here devices
2034 * can only be removed when no resync is
2035 * active, and resync is currently active
2036 */
2037 rdev = conf->mirrors[d].rdev;
2038 if (sync_page_io(rdev, sect, s<<9,
2039 pages[idx],
2040 REQ_OP_READ, false)) {
2041 success = 1;
2042 break;
2043 }
2044 }
2045 d++;
2046 if (d == conf->raid_disks * 2)
2047 d = 0;
2048 } while (!success && d != r1_bio->read_disk);
2049
2050 if (!success) {
2051 int abort = 0;
2052 /* Cannot read from anywhere, this block is lost.
2053 * Record a bad block on each device. If that doesn't
2054 * work just disable and interrupt the recovery.
2055 * Don't fail devices as that won't really help.
2056 */
2057 pr_crit_ratelimited("md/raid1:%s: %pg: unrecoverable I/O read error for block %llu\n",
2058 mdname(mddev), bio->bi_bdev,
2059 (unsigned long long)r1_bio->sector);
2060 for (d = 0; d < conf->raid_disks * 2; d++) {
2061 rdev = conf->mirrors[d].rdev;
2062 if (!rdev || test_bit(Faulty, &rdev->flags))
2063 continue;
2064 if (!rdev_set_badblocks(rdev, sect, s, 0))
2065 abort = 1;
2066 }
2067 if (abort) {
2068 conf->recovery_disabled =
2069 mddev->recovery_disabled;
2070 set_bit(MD_RECOVERY_INTR, &mddev->recovery);
2071 md_done_sync(mddev, r1_bio->sectors, 0);
2072 put_buf(r1_bio);
2073 return 0;
2074 }
2075 /* Try next page */
2076 sectors -= s;
2077 sect += s;
2078 idx++;
2079 continue;
2080 }
2081
2082 start = d;
2083 /* write it back and re-read */
2084 while (d != r1_bio->read_disk) {
2085 if (d == 0)
2086 d = conf->raid_disks * 2;
2087 d--;
2088 if (r1_bio->bios[d]->bi_end_io != end_sync_read)
2089 continue;
2090 rdev = conf->mirrors[d].rdev;
2091 if (r1_sync_page_io(rdev, sect, s,
2092 pages[idx],
2093 REQ_OP_WRITE) == 0) {
2094 r1_bio->bios[d]->bi_end_io = NULL;
2095 rdev_dec_pending(rdev, mddev);
2096 }
2097 }
2098 d = start;
2099 while (d != r1_bio->read_disk) {
2100 if (d == 0)
2101 d = conf->raid_disks * 2;
2102 d--;
2103 if (r1_bio->bios[d]->bi_end_io != end_sync_read)
2104 continue;
2105 rdev = conf->mirrors[d].rdev;
2106 if (r1_sync_page_io(rdev, sect, s,
2107 pages[idx],
2108 REQ_OP_READ) != 0)
2109 atomic_add(s, &rdev->corrected_errors);
2110 }
2111 sectors -= s;
2112 sect += s;
2113 idx ++;
2114 }
2115 set_bit(R1BIO_Uptodate, &r1_bio->state);
2116 bio->bi_status = 0;
2117 return 1;
2118}
2119
2120static void process_checks(struct r1bio *r1_bio)
2121{
2122 /* We have read all readable devices. If we haven't
2123 * got the block, then there is no hope left.
2124 * If we have, then we want to do a comparison
2125 * and skip the write if everything is the same.
2126 * If any blocks failed to read, then we need to
2127 * attempt an over-write
2128 */
2129 struct mddev *mddev = r1_bio->mddev;
2130 struct r1conf *conf = mddev->private;
2131 int primary;
2132 int i;
2133 int vcnt;
2134
2135 /* Fix variable parts of all bios */
2136 vcnt = (r1_bio->sectors + PAGE_SIZE / 512 - 1) >> (PAGE_SHIFT - 9);
2137 for (i = 0; i < conf->raid_disks * 2; i++) {
2138 blk_status_t status;
2139 struct bio *b = r1_bio->bios[i];
2140 struct resync_pages *rp = get_resync_pages(b);
2141 if (b->bi_end_io != end_sync_read)
2142 continue;
2143 /* fixup the bio for reuse, but preserve errno */
2144 status = b->bi_status;
2145 bio_reset(b, conf->mirrors[i].rdev->bdev, REQ_OP_READ);
2146 b->bi_status = status;
2147 b->bi_iter.bi_sector = r1_bio->sector +
2148 conf->mirrors[i].rdev->data_offset;
2149 b->bi_end_io = end_sync_read;
2150 rp->raid_bio = r1_bio;
2151 b->bi_private = rp;
2152
2153 /* initialize bvec table again */
2154 md_bio_reset_resync_pages(b, rp, r1_bio->sectors << 9);
2155 }
2156 for (primary = 0; primary < conf->raid_disks * 2; primary++)
2157 if (r1_bio->bios[primary]->bi_end_io == end_sync_read &&
2158 !r1_bio->bios[primary]->bi_status) {
2159 r1_bio->bios[primary]->bi_end_io = NULL;
2160 rdev_dec_pending(conf->mirrors[primary].rdev, mddev);
2161 break;
2162 }
2163 r1_bio->read_disk = primary;
2164 for (i = 0; i < conf->raid_disks * 2; i++) {
2165 int j = 0;
2166 struct bio *pbio = r1_bio->bios[primary];
2167 struct bio *sbio = r1_bio->bios[i];
2168 blk_status_t status = sbio->bi_status;
2169 struct page **ppages = get_resync_pages(pbio)->pages;
2170 struct page **spages = get_resync_pages(sbio)->pages;
2171 struct bio_vec *bi;
2172 int page_len[RESYNC_PAGES] = { 0 };
2173 struct bvec_iter_all iter_all;
2174
2175 if (sbio->bi_end_io != end_sync_read)
2176 continue;
2177 /* Now we can 'fixup' the error value */
2178 sbio->bi_status = 0;
2179
2180 bio_for_each_segment_all(bi, sbio, iter_all)
2181 page_len[j++] = bi->bv_len;
2182
2183 if (!status) {
2184 for (j = vcnt; j-- ; ) {
2185 if (memcmp(page_address(ppages[j]),
2186 page_address(spages[j]),
2187 page_len[j]))
2188 break;
2189 }
2190 } else
2191 j = 0;
2192 if (j >= 0)
2193 atomic64_add(r1_bio->sectors, &mddev->resync_mismatches);
2194 if (j < 0 || (test_bit(MD_RECOVERY_CHECK, &mddev->recovery)
2195 && !status)) {
2196 /* No need to write to this device. */
2197 sbio->bi_end_io = NULL;
2198 rdev_dec_pending(conf->mirrors[i].rdev, mddev);
2199 continue;
2200 }
2201
2202 bio_copy_data(sbio, pbio);
2203 }
2204}
2205
2206static void sync_request_write(struct mddev *mddev, struct r1bio *r1_bio)
2207{
2208 struct r1conf *conf = mddev->private;
2209 int i;
2210 int disks = conf->raid_disks * 2;
2211 struct bio *wbio;
2212
2213 if (!test_bit(R1BIO_Uptodate, &r1_bio->state))
2214 /* ouch - failed to read all of that. */
2215 if (!fix_sync_read_error(r1_bio))
2216 return;
2217
2218 if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
2219 process_checks(r1_bio);
2220
2221 /*
2222 * schedule writes
2223 */
2224 atomic_set(&r1_bio->remaining, 1);
2225 for (i = 0; i < disks ; i++) {
2226 wbio = r1_bio->bios[i];
2227 if (wbio->bi_end_io == NULL ||
2228 (wbio->bi_end_io == end_sync_read &&
2229 (i == r1_bio->read_disk ||
2230 !test_bit(MD_RECOVERY_SYNC, &mddev->recovery))))
2231 continue;
2232 if (test_bit(Faulty, &conf->mirrors[i].rdev->flags)) {
2233 abort_sync_write(mddev, r1_bio);
2234 continue;
2235 }
2236
2237 wbio->bi_opf = REQ_OP_WRITE;
2238 if (test_bit(FailFast, &conf->mirrors[i].rdev->flags))
2239 wbio->bi_opf |= MD_FAILFAST;
2240
2241 wbio->bi_end_io = end_sync_write;
2242 atomic_inc(&r1_bio->remaining);
2243 md_sync_acct(conf->mirrors[i].rdev->bdev, bio_sectors(wbio));
2244
2245 submit_bio_noacct(wbio);
2246 }
2247
2248 put_sync_write_buf(r1_bio, 1);
2249}
2250
2251/*
2252 * This is a kernel thread which:
2253 *
2254 * 1. Retries failed read operations on working mirrors.
2255 * 2. Updates the raid superblock when problems encounter.
2256 * 3. Performs writes following reads for array synchronising.
2257 */
2258
2259static void fix_read_error(struct r1conf *conf, struct r1bio *r1_bio)
2260{
2261 sector_t sect = r1_bio->sector;
2262 int sectors = r1_bio->sectors;
2263 int read_disk = r1_bio->read_disk;
2264 struct mddev *mddev = conf->mddev;
2265 struct md_rdev *rdev = conf->mirrors[read_disk].rdev;
2266
2267 if (exceed_read_errors(mddev, rdev)) {
2268 r1_bio->bios[r1_bio->read_disk] = IO_BLOCKED;
2269 return;
2270 }
2271
2272 while(sectors) {
2273 int s = sectors;
2274 int d = read_disk;
2275 int success = 0;
2276 int start;
2277
2278 if (s > (PAGE_SIZE>>9))
2279 s = PAGE_SIZE >> 9;
2280
2281 do {
2282 sector_t first_bad;
2283 int bad_sectors;
2284
2285 rdev = conf->mirrors[d].rdev;
2286 if (rdev &&
2287 (test_bit(In_sync, &rdev->flags) ||
2288 (!test_bit(Faulty, &rdev->flags) &&
2289 rdev->recovery_offset >= sect + s)) &&
2290 is_badblock(rdev, sect, s,
2291 &first_bad, &bad_sectors) == 0) {
2292 atomic_inc(&rdev->nr_pending);
2293 if (sync_page_io(rdev, sect, s<<9,
2294 conf->tmppage, REQ_OP_READ, false))
2295 success = 1;
2296 rdev_dec_pending(rdev, mddev);
2297 if (success)
2298 break;
2299 }
2300
2301 d++;
2302 if (d == conf->raid_disks * 2)
2303 d = 0;
2304 } while (d != read_disk);
2305
2306 if (!success) {
2307 /* Cannot read from anywhere - mark it bad */
2308 struct md_rdev *rdev = conf->mirrors[read_disk].rdev;
2309 if (!rdev_set_badblocks(rdev, sect, s, 0))
2310 md_error(mddev, rdev);
2311 break;
2312 }
2313 /* write it back and re-read */
2314 start = d;
2315 while (d != read_disk) {
2316 if (d==0)
2317 d = conf->raid_disks * 2;
2318 d--;
2319 rdev = conf->mirrors[d].rdev;
2320 if (rdev &&
2321 !test_bit(Faulty, &rdev->flags)) {
2322 atomic_inc(&rdev->nr_pending);
2323 r1_sync_page_io(rdev, sect, s,
2324 conf->tmppage, REQ_OP_WRITE);
2325 rdev_dec_pending(rdev, mddev);
2326 }
2327 }
2328 d = start;
2329 while (d != read_disk) {
2330 if (d==0)
2331 d = conf->raid_disks * 2;
2332 d--;
2333 rdev = conf->mirrors[d].rdev;
2334 if (rdev &&
2335 !test_bit(Faulty, &rdev->flags)) {
2336 atomic_inc(&rdev->nr_pending);
2337 if (r1_sync_page_io(rdev, sect, s,
2338 conf->tmppage, REQ_OP_READ)) {
2339 atomic_add(s, &rdev->corrected_errors);
2340 pr_info("md/raid1:%s: read error corrected (%d sectors at %llu on %pg)\n",
2341 mdname(mddev), s,
2342 (unsigned long long)(sect +
2343 rdev->data_offset),
2344 rdev->bdev);
2345 }
2346 rdev_dec_pending(rdev, mddev);
2347 }
2348 }
2349 sectors -= s;
2350 sect += s;
2351 }
2352}
2353
2354static int narrow_write_error(struct r1bio *r1_bio, int i)
2355{
2356 struct mddev *mddev = r1_bio->mddev;
2357 struct r1conf *conf = mddev->private;
2358 struct md_rdev *rdev = conf->mirrors[i].rdev;
2359
2360 /* bio has the data to be written to device 'i' where
2361 * we just recently had a write error.
2362 * We repeatedly clone the bio and trim down to one block,
2363 * then try the write. Where the write fails we record
2364 * a bad block.
2365 * It is conceivable that the bio doesn't exactly align with
2366 * blocks. We must handle this somehow.
2367 *
2368 * We currently own a reference on the rdev.
2369 */
2370
2371 int block_sectors;
2372 sector_t sector;
2373 int sectors;
2374 int sect_to_write = r1_bio->sectors;
2375 int ok = 1;
2376
2377 if (rdev->badblocks.shift < 0)
2378 return 0;
2379
2380 block_sectors = roundup(1 << rdev->badblocks.shift,
2381 bdev_logical_block_size(rdev->bdev) >> 9);
2382 sector = r1_bio->sector;
2383 sectors = ((sector + block_sectors)
2384 & ~(sector_t)(block_sectors - 1))
2385 - sector;
2386
2387 while (sect_to_write) {
2388 struct bio *wbio;
2389 if (sectors > sect_to_write)
2390 sectors = sect_to_write;
2391 /* Write at 'sector' for 'sectors'*/
2392
2393 if (test_bit(R1BIO_BehindIO, &r1_bio->state)) {
2394 wbio = bio_alloc_clone(rdev->bdev,
2395 r1_bio->behind_master_bio,
2396 GFP_NOIO, &mddev->bio_set);
2397 } else {
2398 wbio = bio_alloc_clone(rdev->bdev, r1_bio->master_bio,
2399 GFP_NOIO, &mddev->bio_set);
2400 }
2401
2402 wbio->bi_opf = REQ_OP_WRITE;
2403 wbio->bi_iter.bi_sector = r1_bio->sector;
2404 wbio->bi_iter.bi_size = r1_bio->sectors << 9;
2405
2406 bio_trim(wbio, sector - r1_bio->sector, sectors);
2407 wbio->bi_iter.bi_sector += rdev->data_offset;
2408
2409 if (submit_bio_wait(wbio) < 0)
2410 /* failure! */
2411 ok = rdev_set_badblocks(rdev, sector,
2412 sectors, 0)
2413 && ok;
2414
2415 bio_put(wbio);
2416 sect_to_write -= sectors;
2417 sector += sectors;
2418 sectors = block_sectors;
2419 }
2420 return ok;
2421}
2422
2423static void handle_sync_write_finished(struct r1conf *conf, struct r1bio *r1_bio)
2424{
2425 int m;
2426 int s = r1_bio->sectors;
2427 for (m = 0; m < conf->raid_disks * 2 ; m++) {
2428 struct md_rdev *rdev = conf->mirrors[m].rdev;
2429 struct bio *bio = r1_bio->bios[m];
2430 if (bio->bi_end_io == NULL)
2431 continue;
2432 if (!bio->bi_status &&
2433 test_bit(R1BIO_MadeGood, &r1_bio->state)) {
2434 rdev_clear_badblocks(rdev, r1_bio->sector, s, 0);
2435 }
2436 if (bio->bi_status &&
2437 test_bit(R1BIO_WriteError, &r1_bio->state)) {
2438 if (!rdev_set_badblocks(rdev, r1_bio->sector, s, 0))
2439 md_error(conf->mddev, rdev);
2440 }
2441 }
2442 put_buf(r1_bio);
2443 md_done_sync(conf->mddev, s, 1);
2444}
2445
2446static void handle_write_finished(struct r1conf *conf, struct r1bio *r1_bio)
2447{
2448 int m, idx;
2449 bool fail = false;
2450
2451 for (m = 0; m < conf->raid_disks * 2 ; m++)
2452 if (r1_bio->bios[m] == IO_MADE_GOOD) {
2453 struct md_rdev *rdev = conf->mirrors[m].rdev;
2454 rdev_clear_badblocks(rdev,
2455 r1_bio->sector,
2456 r1_bio->sectors, 0);
2457 rdev_dec_pending(rdev, conf->mddev);
2458 } else if (r1_bio->bios[m] != NULL) {
2459 /* This drive got a write error. We need to
2460 * narrow down and record precise write
2461 * errors.
2462 */
2463 fail = true;
2464 if (!narrow_write_error(r1_bio, m)) {
2465 md_error(conf->mddev,
2466 conf->mirrors[m].rdev);
2467 /* an I/O failed, we can't clear the bitmap */
2468 set_bit(R1BIO_Degraded, &r1_bio->state);
2469 }
2470 rdev_dec_pending(conf->mirrors[m].rdev,
2471 conf->mddev);
2472 }
2473 if (fail) {
2474 spin_lock_irq(&conf->device_lock);
2475 list_add(&r1_bio->retry_list, &conf->bio_end_io_list);
2476 idx = sector_to_idx(r1_bio->sector);
2477 atomic_inc(&conf->nr_queued[idx]);
2478 spin_unlock_irq(&conf->device_lock);
2479 /*
2480 * In case freeze_array() is waiting for condition
2481 * get_unqueued_pending() == extra to be true.
2482 */
2483 wake_up(&conf->wait_barrier);
2484 md_wakeup_thread(conf->mddev->thread);
2485 } else {
2486 if (test_bit(R1BIO_WriteError, &r1_bio->state))
2487 close_write(r1_bio);
2488 raid_end_bio_io(r1_bio);
2489 }
2490}
2491
2492static void handle_read_error(struct r1conf *conf, struct r1bio *r1_bio)
2493{
2494 struct mddev *mddev = conf->mddev;
2495 struct bio *bio;
2496 struct md_rdev *rdev;
2497 sector_t sector;
2498
2499 clear_bit(R1BIO_ReadError, &r1_bio->state);
2500 /* we got a read error. Maybe the drive is bad. Maybe just
2501 * the block and we can fix it.
2502 * We freeze all other IO, and try reading the block from
2503 * other devices. When we find one, we re-write
2504 * and check it that fixes the read error.
2505 * This is all done synchronously while the array is
2506 * frozen
2507 */
2508
2509 bio = r1_bio->bios[r1_bio->read_disk];
2510 bio_put(bio);
2511 r1_bio->bios[r1_bio->read_disk] = NULL;
2512
2513 rdev = conf->mirrors[r1_bio->read_disk].rdev;
2514 if (mddev->ro == 0
2515 && !test_bit(FailFast, &rdev->flags)) {
2516 freeze_array(conf, 1);
2517 fix_read_error(conf, r1_bio);
2518 unfreeze_array(conf);
2519 } else if (mddev->ro == 0 && test_bit(FailFast, &rdev->flags)) {
2520 md_error(mddev, rdev);
2521 } else {
2522 r1_bio->bios[r1_bio->read_disk] = IO_BLOCKED;
2523 }
2524
2525 rdev_dec_pending(rdev, conf->mddev);
2526 sector = r1_bio->sector;
2527 bio = r1_bio->master_bio;
2528
2529 /* Reuse the old r1_bio so that the IO_BLOCKED settings are preserved */
2530 r1_bio->state = 0;
2531 raid1_read_request(mddev, bio, r1_bio->sectors, r1_bio);
2532 allow_barrier(conf, sector);
2533}
2534
2535static void raid1d(struct md_thread *thread)
2536{
2537 struct mddev *mddev = thread->mddev;
2538 struct r1bio *r1_bio;
2539 unsigned long flags;
2540 struct r1conf *conf = mddev->private;
2541 struct list_head *head = &conf->retry_list;
2542 struct blk_plug plug;
2543 int idx;
2544
2545 md_check_recovery(mddev);
2546
2547 if (!list_empty_careful(&conf->bio_end_io_list) &&
2548 !test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags)) {
2549 LIST_HEAD(tmp);
2550 spin_lock_irqsave(&conf->device_lock, flags);
2551 if (!test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags))
2552 list_splice_init(&conf->bio_end_io_list, &tmp);
2553 spin_unlock_irqrestore(&conf->device_lock, flags);
2554 while (!list_empty(&tmp)) {
2555 r1_bio = list_first_entry(&tmp, struct r1bio,
2556 retry_list);
2557 list_del(&r1_bio->retry_list);
2558 idx = sector_to_idx(r1_bio->sector);
2559 atomic_dec(&conf->nr_queued[idx]);
2560 if (mddev->degraded)
2561 set_bit(R1BIO_Degraded, &r1_bio->state);
2562 if (test_bit(R1BIO_WriteError, &r1_bio->state))
2563 close_write(r1_bio);
2564 raid_end_bio_io(r1_bio);
2565 }
2566 }
2567
2568 blk_start_plug(&plug);
2569 for (;;) {
2570
2571 flush_pending_writes(conf);
2572
2573 spin_lock_irqsave(&conf->device_lock, flags);
2574 if (list_empty(head)) {
2575 spin_unlock_irqrestore(&conf->device_lock, flags);
2576 break;
2577 }
2578 r1_bio = list_entry(head->prev, struct r1bio, retry_list);
2579 list_del(head->prev);
2580 idx = sector_to_idx(r1_bio->sector);
2581 atomic_dec(&conf->nr_queued[idx]);
2582 spin_unlock_irqrestore(&conf->device_lock, flags);
2583
2584 mddev = r1_bio->mddev;
2585 conf = mddev->private;
2586 if (test_bit(R1BIO_IsSync, &r1_bio->state)) {
2587 if (test_bit(R1BIO_MadeGood, &r1_bio->state) ||
2588 test_bit(R1BIO_WriteError, &r1_bio->state))
2589 handle_sync_write_finished(conf, r1_bio);
2590 else
2591 sync_request_write(mddev, r1_bio);
2592 } else if (test_bit(R1BIO_MadeGood, &r1_bio->state) ||
2593 test_bit(R1BIO_WriteError, &r1_bio->state))
2594 handle_write_finished(conf, r1_bio);
2595 else if (test_bit(R1BIO_ReadError, &r1_bio->state))
2596 handle_read_error(conf, r1_bio);
2597 else
2598 WARN_ON_ONCE(1);
2599
2600 cond_resched();
2601 if (mddev->sb_flags & ~(1<<MD_SB_CHANGE_PENDING))
2602 md_check_recovery(mddev);
2603 }
2604 blk_finish_plug(&plug);
2605}
2606
2607static int init_resync(struct r1conf *conf)
2608{
2609 int buffs;
2610
2611 buffs = RESYNC_WINDOW / RESYNC_BLOCK_SIZE;
2612 BUG_ON(mempool_initialized(&conf->r1buf_pool));
2613
2614 return mempool_init(&conf->r1buf_pool, buffs, r1buf_pool_alloc,
2615 r1buf_pool_free, conf->poolinfo);
2616}
2617
2618static struct r1bio *raid1_alloc_init_r1buf(struct r1conf *conf)
2619{
2620 struct r1bio *r1bio = mempool_alloc(&conf->r1buf_pool, GFP_NOIO);
2621 struct resync_pages *rps;
2622 struct bio *bio;
2623 int i;
2624
2625 for (i = conf->poolinfo->raid_disks; i--; ) {
2626 bio = r1bio->bios[i];
2627 rps = bio->bi_private;
2628 bio_reset(bio, NULL, 0);
2629 bio->bi_private = rps;
2630 }
2631 r1bio->master_bio = NULL;
2632 return r1bio;
2633}
2634
2635/*
2636 * perform a "sync" on one "block"
2637 *
2638 * We need to make sure that no normal I/O request - particularly write
2639 * requests - conflict with active sync requests.
2640 *
2641 * This is achieved by tracking pending requests and a 'barrier' concept
2642 * that can be installed to exclude normal IO requests.
2643 */
2644
2645static sector_t raid1_sync_request(struct mddev *mddev, sector_t sector_nr,
2646 int *skipped)
2647{
2648 struct r1conf *conf = mddev->private;
2649 struct r1bio *r1_bio;
2650 struct bio *bio;
2651 sector_t max_sector, nr_sectors;
2652 int disk = -1;
2653 int i;
2654 int wonly = -1;
2655 int write_targets = 0, read_targets = 0;
2656 sector_t sync_blocks;
2657 int still_degraded = 0;
2658 int good_sectors = RESYNC_SECTORS;
2659 int min_bad = 0; /* number of sectors that are bad in all devices */
2660 int idx = sector_to_idx(sector_nr);
2661 int page_idx = 0;
2662
2663 if (!mempool_initialized(&conf->r1buf_pool))
2664 if (init_resync(conf))
2665 return 0;
2666
2667 max_sector = mddev->dev_sectors;
2668 if (sector_nr >= max_sector) {
2669 /* If we aborted, we need to abort the
2670 * sync on the 'current' bitmap chunk (there will
2671 * only be one in raid1 resync.
2672 * We can find the current addess in mddev->curr_resync
2673 */
2674 if (mddev->curr_resync < max_sector) /* aborted */
2675 md_bitmap_end_sync(mddev->bitmap, mddev->curr_resync,
2676 &sync_blocks, 1);
2677 else /* completed sync */
2678 conf->fullsync = 0;
2679
2680 md_bitmap_close_sync(mddev->bitmap);
2681 close_sync(conf);
2682
2683 if (mddev_is_clustered(mddev)) {
2684 conf->cluster_sync_low = 0;
2685 conf->cluster_sync_high = 0;
2686 }
2687 return 0;
2688 }
2689
2690 if (mddev->bitmap == NULL &&
2691 mddev->recovery_cp == MaxSector &&
2692 !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery) &&
2693 conf->fullsync == 0) {
2694 *skipped = 1;
2695 return max_sector - sector_nr;
2696 }
2697 /* before building a request, check if we can skip these blocks..
2698 * This call the bitmap_start_sync doesn't actually record anything
2699 */
2700 if (!md_bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, 1) &&
2701 !conf->fullsync && !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) {
2702 /* We can skip this block, and probably several more */
2703 *skipped = 1;
2704 return sync_blocks;
2705 }
2706
2707 /*
2708 * If there is non-resync activity waiting for a turn, then let it
2709 * though before starting on this new sync request.
2710 */
2711 if (atomic_read(&conf->nr_waiting[idx]))
2712 schedule_timeout_uninterruptible(1);
2713
2714 /* we are incrementing sector_nr below. To be safe, we check against
2715 * sector_nr + two times RESYNC_SECTORS
2716 */
2717
2718 md_bitmap_cond_end_sync(mddev->bitmap, sector_nr,
2719 mddev_is_clustered(mddev) && (sector_nr + 2 * RESYNC_SECTORS > conf->cluster_sync_high));
2720
2721
2722 if (raise_barrier(conf, sector_nr))
2723 return 0;
2724
2725 r1_bio = raid1_alloc_init_r1buf(conf);
2726
2727 /*
2728 * If we get a correctably read error during resync or recovery,
2729 * we might want to read from a different device. So we
2730 * flag all drives that could conceivably be read from for READ,
2731 * and any others (which will be non-In_sync devices) for WRITE.
2732 * If a read fails, we try reading from something else for which READ
2733 * is OK.
2734 */
2735
2736 r1_bio->mddev = mddev;
2737 r1_bio->sector = sector_nr;
2738 r1_bio->state = 0;
2739 set_bit(R1BIO_IsSync, &r1_bio->state);
2740 /* make sure good_sectors won't go across barrier unit boundary */
2741 good_sectors = align_to_barrier_unit_end(sector_nr, good_sectors);
2742
2743 for (i = 0; i < conf->raid_disks * 2; i++) {
2744 struct md_rdev *rdev;
2745 bio = r1_bio->bios[i];
2746
2747 rdev = conf->mirrors[i].rdev;
2748 if (rdev == NULL ||
2749 test_bit(Faulty, &rdev->flags)) {
2750 if (i < conf->raid_disks)
2751 still_degraded = 1;
2752 } else if (!test_bit(In_sync, &rdev->flags)) {
2753 bio->bi_opf = REQ_OP_WRITE;
2754 bio->bi_end_io = end_sync_write;
2755 write_targets ++;
2756 } else {
2757 /* may need to read from here */
2758 sector_t first_bad = MaxSector;
2759 int bad_sectors;
2760
2761 if (is_badblock(rdev, sector_nr, good_sectors,
2762 &first_bad, &bad_sectors)) {
2763 if (first_bad > sector_nr)
2764 good_sectors = first_bad - sector_nr;
2765 else {
2766 bad_sectors -= (sector_nr - first_bad);
2767 if (min_bad == 0 ||
2768 min_bad > bad_sectors)
2769 min_bad = bad_sectors;
2770 }
2771 }
2772 if (sector_nr < first_bad) {
2773 if (test_bit(WriteMostly, &rdev->flags)) {
2774 if (wonly < 0)
2775 wonly = i;
2776 } else {
2777 if (disk < 0)
2778 disk = i;
2779 }
2780 bio->bi_opf = REQ_OP_READ;
2781 bio->bi_end_io = end_sync_read;
2782 read_targets++;
2783 } else if (!test_bit(WriteErrorSeen, &rdev->flags) &&
2784 test_bit(MD_RECOVERY_SYNC, &mddev->recovery) &&
2785 !test_bit(MD_RECOVERY_CHECK, &mddev->recovery)) {
2786 /*
2787 * The device is suitable for reading (InSync),
2788 * but has bad block(s) here. Let's try to correct them,
2789 * if we are doing resync or repair. Otherwise, leave
2790 * this device alone for this sync request.
2791 */
2792 bio->bi_opf = REQ_OP_WRITE;
2793 bio->bi_end_io = end_sync_write;
2794 write_targets++;
2795 }
2796 }
2797 if (rdev && bio->bi_end_io) {
2798 atomic_inc(&rdev->nr_pending);
2799 bio->bi_iter.bi_sector = sector_nr + rdev->data_offset;
2800 bio_set_dev(bio, rdev->bdev);
2801 if (test_bit(FailFast, &rdev->flags))
2802 bio->bi_opf |= MD_FAILFAST;
2803 }
2804 }
2805 if (disk < 0)
2806 disk = wonly;
2807 r1_bio->read_disk = disk;
2808
2809 if (read_targets == 0 && min_bad > 0) {
2810 /* These sectors are bad on all InSync devices, so we
2811 * need to mark them bad on all write targets
2812 */
2813 int ok = 1;
2814 for (i = 0 ; i < conf->raid_disks * 2 ; i++)
2815 if (r1_bio->bios[i]->bi_end_io == end_sync_write) {
2816 struct md_rdev *rdev = conf->mirrors[i].rdev;
2817 ok = rdev_set_badblocks(rdev, sector_nr,
2818 min_bad, 0
2819 ) && ok;
2820 }
2821 set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
2822 *skipped = 1;
2823 put_buf(r1_bio);
2824
2825 if (!ok) {
2826 /* Cannot record the badblocks, so need to
2827 * abort the resync.
2828 * If there are multiple read targets, could just
2829 * fail the really bad ones ???
2830 */
2831 conf->recovery_disabled = mddev->recovery_disabled;
2832 set_bit(MD_RECOVERY_INTR, &mddev->recovery);
2833 return 0;
2834 } else
2835 return min_bad;
2836
2837 }
2838 if (min_bad > 0 && min_bad < good_sectors) {
2839 /* only resync enough to reach the next bad->good
2840 * transition */
2841 good_sectors = min_bad;
2842 }
2843
2844 if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) && read_targets > 0)
2845 /* extra read targets are also write targets */
2846 write_targets += read_targets-1;
2847
2848 if (write_targets == 0 || read_targets == 0) {
2849 /* There is nowhere to write, so all non-sync
2850 * drives must be failed - so we are finished
2851 */
2852 sector_t rv;
2853 if (min_bad > 0)
2854 max_sector = sector_nr + min_bad;
2855 rv = max_sector - sector_nr;
2856 *skipped = 1;
2857 put_buf(r1_bio);
2858 return rv;
2859 }
2860
2861 if (max_sector > mddev->resync_max)
2862 max_sector = mddev->resync_max; /* Don't do IO beyond here */
2863 if (max_sector > sector_nr + good_sectors)
2864 max_sector = sector_nr + good_sectors;
2865 nr_sectors = 0;
2866 sync_blocks = 0;
2867 do {
2868 struct page *page;
2869 int len = PAGE_SIZE;
2870 if (sector_nr + (len>>9) > max_sector)
2871 len = (max_sector - sector_nr) << 9;
2872 if (len == 0)
2873 break;
2874 if (sync_blocks == 0) {
2875 if (!md_bitmap_start_sync(mddev->bitmap, sector_nr,
2876 &sync_blocks, still_degraded) &&
2877 !conf->fullsync &&
2878 !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
2879 break;
2880 if ((len >> 9) > sync_blocks)
2881 len = sync_blocks<<9;
2882 }
2883
2884 for (i = 0 ; i < conf->raid_disks * 2; i++) {
2885 struct resync_pages *rp;
2886
2887 bio = r1_bio->bios[i];
2888 rp = get_resync_pages(bio);
2889 if (bio->bi_end_io) {
2890 page = resync_fetch_page(rp, page_idx);
2891
2892 /*
2893 * won't fail because the vec table is big
2894 * enough to hold all these pages
2895 */
2896 __bio_add_page(bio, page, len, 0);
2897 }
2898 }
2899 nr_sectors += len>>9;
2900 sector_nr += len>>9;
2901 sync_blocks -= (len>>9);
2902 } while (++page_idx < RESYNC_PAGES);
2903
2904 r1_bio->sectors = nr_sectors;
2905
2906 if (mddev_is_clustered(mddev) &&
2907 conf->cluster_sync_high < sector_nr + nr_sectors) {
2908 conf->cluster_sync_low = mddev->curr_resync_completed;
2909 conf->cluster_sync_high = conf->cluster_sync_low + CLUSTER_RESYNC_WINDOW_SECTORS;
2910 /* Send resync message */
2911 md_cluster_ops->resync_info_update(mddev,
2912 conf->cluster_sync_low,
2913 conf->cluster_sync_high);
2914 }
2915
2916 /* For a user-requested sync, we read all readable devices and do a
2917 * compare
2918 */
2919 if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) {
2920 atomic_set(&r1_bio->remaining, read_targets);
2921 for (i = 0; i < conf->raid_disks * 2 && read_targets; i++) {
2922 bio = r1_bio->bios[i];
2923 if (bio->bi_end_io == end_sync_read) {
2924 read_targets--;
2925 md_sync_acct_bio(bio, nr_sectors);
2926 if (read_targets == 1)
2927 bio->bi_opf &= ~MD_FAILFAST;
2928 submit_bio_noacct(bio);
2929 }
2930 }
2931 } else {
2932 atomic_set(&r1_bio->remaining, 1);
2933 bio = r1_bio->bios[r1_bio->read_disk];
2934 md_sync_acct_bio(bio, nr_sectors);
2935 if (read_targets == 1)
2936 bio->bi_opf &= ~MD_FAILFAST;
2937 submit_bio_noacct(bio);
2938 }
2939 return nr_sectors;
2940}
2941
2942static sector_t raid1_size(struct mddev *mddev, sector_t sectors, int raid_disks)
2943{
2944 if (sectors)
2945 return sectors;
2946
2947 return mddev->dev_sectors;
2948}
2949
2950static struct r1conf *setup_conf(struct mddev *mddev)
2951{
2952 struct r1conf *conf;
2953 int i;
2954 struct raid1_info *disk;
2955 struct md_rdev *rdev;
2956 int err = -ENOMEM;
2957
2958 conf = kzalloc(sizeof(struct r1conf), GFP_KERNEL);
2959 if (!conf)
2960 goto abort;
2961
2962 conf->nr_pending = kcalloc(BARRIER_BUCKETS_NR,
2963 sizeof(atomic_t), GFP_KERNEL);
2964 if (!conf->nr_pending)
2965 goto abort;
2966
2967 conf->nr_waiting = kcalloc(BARRIER_BUCKETS_NR,
2968 sizeof(atomic_t), GFP_KERNEL);
2969 if (!conf->nr_waiting)
2970 goto abort;
2971
2972 conf->nr_queued = kcalloc(BARRIER_BUCKETS_NR,
2973 sizeof(atomic_t), GFP_KERNEL);
2974 if (!conf->nr_queued)
2975 goto abort;
2976
2977 conf->barrier = kcalloc(BARRIER_BUCKETS_NR,
2978 sizeof(atomic_t), GFP_KERNEL);
2979 if (!conf->barrier)
2980 goto abort;
2981
2982 conf->mirrors = kzalloc(array3_size(sizeof(struct raid1_info),
2983 mddev->raid_disks, 2),
2984 GFP_KERNEL);
2985 if (!conf->mirrors)
2986 goto abort;
2987
2988 conf->tmppage = alloc_page(GFP_KERNEL);
2989 if (!conf->tmppage)
2990 goto abort;
2991
2992 conf->poolinfo = kzalloc(sizeof(*conf->poolinfo), GFP_KERNEL);
2993 if (!conf->poolinfo)
2994 goto abort;
2995 conf->poolinfo->raid_disks = mddev->raid_disks * 2;
2996 err = mempool_init(&conf->r1bio_pool, NR_RAID_BIOS, r1bio_pool_alloc,
2997 rbio_pool_free, conf->poolinfo);
2998 if (err)
2999 goto abort;
3000
3001 err = bioset_init(&conf->bio_split, BIO_POOL_SIZE, 0, 0);
3002 if (err)
3003 goto abort;
3004
3005 conf->poolinfo->mddev = mddev;
3006
3007 err = -EINVAL;
3008 spin_lock_init(&conf->device_lock);
3009 rdev_for_each(rdev, mddev) {
3010 int disk_idx = rdev->raid_disk;
3011 if (disk_idx >= mddev->raid_disks
3012 || disk_idx < 0)
3013 continue;
3014 if (test_bit(Replacement, &rdev->flags))
3015 disk = conf->mirrors + mddev->raid_disks + disk_idx;
3016 else
3017 disk = conf->mirrors + disk_idx;
3018
3019 if (disk->rdev)
3020 goto abort;
3021 disk->rdev = rdev;
3022 disk->head_position = 0;
3023 disk->seq_start = MaxSector;
3024 }
3025 conf->raid_disks = mddev->raid_disks;
3026 conf->mddev = mddev;
3027 INIT_LIST_HEAD(&conf->retry_list);
3028 INIT_LIST_HEAD(&conf->bio_end_io_list);
3029
3030 spin_lock_init(&conf->resync_lock);
3031 init_waitqueue_head(&conf->wait_barrier);
3032
3033 bio_list_init(&conf->pending_bio_list);
3034 conf->recovery_disabled = mddev->recovery_disabled - 1;
3035
3036 err = -EIO;
3037 for (i = 0; i < conf->raid_disks * 2; i++) {
3038
3039 disk = conf->mirrors + i;
3040
3041 if (i < conf->raid_disks &&
3042 disk[conf->raid_disks].rdev) {
3043 /* This slot has a replacement. */
3044 if (!disk->rdev) {
3045 /* No original, just make the replacement
3046 * a recovering spare
3047 */
3048 disk->rdev =
3049 disk[conf->raid_disks].rdev;
3050 disk[conf->raid_disks].rdev = NULL;
3051 } else if (!test_bit(In_sync, &disk->rdev->flags))
3052 /* Original is not in_sync - bad */
3053 goto abort;
3054 }
3055
3056 if (!disk->rdev ||
3057 !test_bit(In_sync, &disk->rdev->flags)) {
3058 disk->head_position = 0;
3059 if (disk->rdev &&
3060 (disk->rdev->saved_raid_disk < 0))
3061 conf->fullsync = 1;
3062 }
3063 }
3064
3065 err = -ENOMEM;
3066 rcu_assign_pointer(conf->thread,
3067 md_register_thread(raid1d, mddev, "raid1"));
3068 if (!conf->thread)
3069 goto abort;
3070
3071 return conf;
3072
3073 abort:
3074 if (conf) {
3075 mempool_exit(&conf->r1bio_pool);
3076 kfree(conf->mirrors);
3077 safe_put_page(conf->tmppage);
3078 kfree(conf->poolinfo);
3079 kfree(conf->nr_pending);
3080 kfree(conf->nr_waiting);
3081 kfree(conf->nr_queued);
3082 kfree(conf->barrier);
3083 bioset_exit(&conf->bio_split);
3084 kfree(conf);
3085 }
3086 return ERR_PTR(err);
3087}
3088
3089static void raid1_free(struct mddev *mddev, void *priv);
3090static int raid1_run(struct mddev *mddev)
3091{
3092 struct r1conf *conf;
3093 int i;
3094 struct md_rdev *rdev;
3095 int ret;
3096
3097 if (mddev->level != 1) {
3098 pr_warn("md/raid1:%s: raid level not set to mirroring (%d)\n",
3099 mdname(mddev), mddev->level);
3100 return -EIO;
3101 }
3102 if (mddev->reshape_position != MaxSector) {
3103 pr_warn("md/raid1:%s: reshape_position set but not supported\n",
3104 mdname(mddev));
3105 return -EIO;
3106 }
3107
3108 /*
3109 * copy the already verified devices into our private RAID1
3110 * bookkeeping area. [whatever we allocate in run(),
3111 * should be freed in raid1_free()]
3112 */
3113 if (mddev->private == NULL)
3114 conf = setup_conf(mddev);
3115 else
3116 conf = mddev->private;
3117
3118 if (IS_ERR(conf))
3119 return PTR_ERR(conf);
3120
3121 if (mddev->queue)
3122 blk_queue_max_write_zeroes_sectors(mddev->queue, 0);
3123
3124 rdev_for_each(rdev, mddev) {
3125 if (!mddev->gendisk)
3126 continue;
3127 disk_stack_limits(mddev->gendisk, rdev->bdev,
3128 rdev->data_offset << 9);
3129 }
3130
3131 mddev->degraded = 0;
3132 for (i = 0; i < conf->raid_disks; i++)
3133 if (conf->mirrors[i].rdev == NULL ||
3134 !test_bit(In_sync, &conf->mirrors[i].rdev->flags) ||
3135 test_bit(Faulty, &conf->mirrors[i].rdev->flags))
3136 mddev->degraded++;
3137 /*
3138 * RAID1 needs at least one disk in active
3139 */
3140 if (conf->raid_disks - mddev->degraded < 1) {
3141 md_unregister_thread(mddev, &conf->thread);
3142 ret = -EINVAL;
3143 goto abort;
3144 }
3145
3146 if (conf->raid_disks - mddev->degraded == 1)
3147 mddev->recovery_cp = MaxSector;
3148
3149 if (mddev->recovery_cp != MaxSector)
3150 pr_info("md/raid1:%s: not clean -- starting background reconstruction\n",
3151 mdname(mddev));
3152 pr_info("md/raid1:%s: active with %d out of %d mirrors\n",
3153 mdname(mddev), mddev->raid_disks - mddev->degraded,
3154 mddev->raid_disks);
3155
3156 /*
3157 * Ok, everything is just fine now
3158 */
3159 rcu_assign_pointer(mddev->thread, conf->thread);
3160 rcu_assign_pointer(conf->thread, NULL);
3161 mddev->private = conf;
3162 set_bit(MD_FAILFAST_SUPPORTED, &mddev->flags);
3163
3164 md_set_array_sectors(mddev, raid1_size(mddev, 0, 0));
3165
3166 ret = md_integrity_register(mddev);
3167 if (ret) {
3168 md_unregister_thread(mddev, &mddev->thread);
3169 goto abort;
3170 }
3171 return 0;
3172
3173abort:
3174 raid1_free(mddev, conf);
3175 return ret;
3176}
3177
3178static void raid1_free(struct mddev *mddev, void *priv)
3179{
3180 struct r1conf *conf = priv;
3181
3182 mempool_exit(&conf->r1bio_pool);
3183 kfree(conf->mirrors);
3184 safe_put_page(conf->tmppage);
3185 kfree(conf->poolinfo);
3186 kfree(conf->nr_pending);
3187 kfree(conf->nr_waiting);
3188 kfree(conf->nr_queued);
3189 kfree(conf->barrier);
3190 bioset_exit(&conf->bio_split);
3191 kfree(conf);
3192}
3193
3194static int raid1_resize(struct mddev *mddev, sector_t sectors)
3195{
3196 /* no resync is happening, and there is enough space
3197 * on all devices, so we can resize.
3198 * We need to make sure resync covers any new space.
3199 * If the array is shrinking we should possibly wait until
3200 * any io in the removed space completes, but it hardly seems
3201 * worth it.
3202 */
3203 sector_t newsize = raid1_size(mddev, sectors, 0);
3204 if (mddev->external_size &&
3205 mddev->array_sectors > newsize)
3206 return -EINVAL;
3207 if (mddev->bitmap) {
3208 int ret = md_bitmap_resize(mddev->bitmap, newsize, 0, 0);
3209 if (ret)
3210 return ret;
3211 }
3212 md_set_array_sectors(mddev, newsize);
3213 if (sectors > mddev->dev_sectors &&
3214 mddev->recovery_cp > mddev->dev_sectors) {
3215 mddev->recovery_cp = mddev->dev_sectors;
3216 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3217 }
3218 mddev->dev_sectors = sectors;
3219 mddev->resync_max_sectors = sectors;
3220 return 0;
3221}
3222
3223static int raid1_reshape(struct mddev *mddev)
3224{
3225 /* We need to:
3226 * 1/ resize the r1bio_pool
3227 * 2/ resize conf->mirrors
3228 *
3229 * We allocate a new r1bio_pool if we can.
3230 * Then raise a device barrier and wait until all IO stops.
3231 * Then resize conf->mirrors and swap in the new r1bio pool.
3232 *
3233 * At the same time, we "pack" the devices so that all the missing
3234 * devices have the higher raid_disk numbers.
3235 */
3236 mempool_t newpool, oldpool;
3237 struct pool_info *newpoolinfo;
3238 struct raid1_info *newmirrors;
3239 struct r1conf *conf = mddev->private;
3240 int cnt, raid_disks;
3241 unsigned long flags;
3242 int d, d2;
3243 int ret;
3244
3245 memset(&newpool, 0, sizeof(newpool));
3246 memset(&oldpool, 0, sizeof(oldpool));
3247
3248 /* Cannot change chunk_size, layout, or level */
3249 if (mddev->chunk_sectors != mddev->new_chunk_sectors ||
3250 mddev->layout != mddev->new_layout ||
3251 mddev->level != mddev->new_level) {
3252 mddev->new_chunk_sectors = mddev->chunk_sectors;
3253 mddev->new_layout = mddev->layout;
3254 mddev->new_level = mddev->level;
3255 return -EINVAL;
3256 }
3257
3258 if (!mddev_is_clustered(mddev))
3259 md_allow_write(mddev);
3260
3261 raid_disks = mddev->raid_disks + mddev->delta_disks;
3262
3263 if (raid_disks < conf->raid_disks) {
3264 cnt=0;
3265 for (d= 0; d < conf->raid_disks; d++)
3266 if (conf->mirrors[d].rdev)
3267 cnt++;
3268 if (cnt > raid_disks)
3269 return -EBUSY;
3270 }
3271
3272 newpoolinfo = kmalloc(sizeof(*newpoolinfo), GFP_KERNEL);
3273 if (!newpoolinfo)
3274 return -ENOMEM;
3275 newpoolinfo->mddev = mddev;
3276 newpoolinfo->raid_disks = raid_disks * 2;
3277
3278 ret = mempool_init(&newpool, NR_RAID_BIOS, r1bio_pool_alloc,
3279 rbio_pool_free, newpoolinfo);
3280 if (ret) {
3281 kfree(newpoolinfo);
3282 return ret;
3283 }
3284 newmirrors = kzalloc(array3_size(sizeof(struct raid1_info),
3285 raid_disks, 2),
3286 GFP_KERNEL);
3287 if (!newmirrors) {
3288 kfree(newpoolinfo);
3289 mempool_exit(&newpool);
3290 return -ENOMEM;
3291 }
3292
3293 freeze_array(conf, 0);
3294
3295 /* ok, everything is stopped */
3296 oldpool = conf->r1bio_pool;
3297 conf->r1bio_pool = newpool;
3298
3299 for (d = d2 = 0; d < conf->raid_disks; d++) {
3300 struct md_rdev *rdev = conf->mirrors[d].rdev;
3301 if (rdev && rdev->raid_disk != d2) {
3302 sysfs_unlink_rdev(mddev, rdev);
3303 rdev->raid_disk = d2;
3304 sysfs_unlink_rdev(mddev, rdev);
3305 if (sysfs_link_rdev(mddev, rdev))
3306 pr_warn("md/raid1:%s: cannot register rd%d\n",
3307 mdname(mddev), rdev->raid_disk);
3308 }
3309 if (rdev)
3310 newmirrors[d2++].rdev = rdev;
3311 }
3312 kfree(conf->mirrors);
3313 conf->mirrors = newmirrors;
3314 kfree(conf->poolinfo);
3315 conf->poolinfo = newpoolinfo;
3316
3317 spin_lock_irqsave(&conf->device_lock, flags);
3318 mddev->degraded += (raid_disks - conf->raid_disks);
3319 spin_unlock_irqrestore(&conf->device_lock, flags);
3320 conf->raid_disks = mddev->raid_disks = raid_disks;
3321 mddev->delta_disks = 0;
3322
3323 unfreeze_array(conf);
3324
3325 set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
3326 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3327 md_wakeup_thread(mddev->thread);
3328
3329 mempool_exit(&oldpool);
3330 return 0;
3331}
3332
3333static void raid1_quiesce(struct mddev *mddev, int quiesce)
3334{
3335 struct r1conf *conf = mddev->private;
3336
3337 if (quiesce)
3338 freeze_array(conf, 0);
3339 else
3340 unfreeze_array(conf);
3341}
3342
3343static void *raid1_takeover(struct mddev *mddev)
3344{
3345 /* raid1 can take over:
3346 * raid5 with 2 devices, any layout or chunk size
3347 */
3348 if (mddev->level == 5 && mddev->raid_disks == 2) {
3349 struct r1conf *conf;
3350 mddev->new_level = 1;
3351 mddev->new_layout = 0;
3352 mddev->new_chunk_sectors = 0;
3353 conf = setup_conf(mddev);
3354 if (!IS_ERR(conf)) {
3355 /* Array must appear to be quiesced */
3356 conf->array_frozen = 1;
3357 mddev_clear_unsupported_flags(mddev,
3358 UNSUPPORTED_MDDEV_FLAGS);
3359 }
3360 return conf;
3361 }
3362 return ERR_PTR(-EINVAL);
3363}
3364
3365static struct md_personality raid1_personality =
3366{
3367 .name = "raid1",
3368 .level = 1,
3369 .owner = THIS_MODULE,
3370 .make_request = raid1_make_request,
3371 .run = raid1_run,
3372 .free = raid1_free,
3373 .status = raid1_status,
3374 .error_handler = raid1_error,
3375 .hot_add_disk = raid1_add_disk,
3376 .hot_remove_disk= raid1_remove_disk,
3377 .spare_active = raid1_spare_active,
3378 .sync_request = raid1_sync_request,
3379 .resize = raid1_resize,
3380 .size = raid1_size,
3381 .check_reshape = raid1_reshape,
3382 .quiesce = raid1_quiesce,
3383 .takeover = raid1_takeover,
3384};
3385
3386static int __init raid_init(void)
3387{
3388 return register_md_personality(&raid1_personality);
3389}
3390
3391static void raid_exit(void)
3392{
3393 unregister_md_personality(&raid1_personality);
3394}
3395
3396module_init(raid_init);
3397module_exit(raid_exit);
3398MODULE_LICENSE("GPL");
3399MODULE_DESCRIPTION("RAID1 (mirroring) personality for MD");
3400MODULE_ALIAS("md-personality-3"); /* RAID1 */
3401MODULE_ALIAS("md-raid1");
3402MODULE_ALIAS("md-level-1");
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * raid1.c : Multiple Devices driver for Linux
4 *
5 * Copyright (C) 1999, 2000, 2001 Ingo Molnar, Red Hat
6 *
7 * Copyright (C) 1996, 1997, 1998 Ingo Molnar, Miguel de Icaza, Gadi Oxman
8 *
9 * RAID-1 management functions.
10 *
11 * Better read-balancing code written by Mika Kuoppala <miku@iki.fi>, 2000
12 *
13 * Fixes to reconstruction by Jakob Østergaard" <jakob@ostenfeld.dk>
14 * Various fixes by Neil Brown <neilb@cse.unsw.edu.au>
15 *
16 * Changes by Peter T. Breuer <ptb@it.uc3m.es> 31/1/2003 to support
17 * bitmapped intelligence in resync:
18 *
19 * - bitmap marked during normal i/o
20 * - bitmap used to skip nondirty blocks during sync
21 *
22 * Additions to bitmap code, (C) 2003-2004 Paul Clements, SteelEye Technology:
23 * - persistent bitmap code
24 */
25
26#include <linux/slab.h>
27#include <linux/delay.h>
28#include <linux/blkdev.h>
29#include <linux/module.h>
30#include <linux/seq_file.h>
31#include <linux/ratelimit.h>
32#include <linux/interval_tree_generic.h>
33
34#include <trace/events/block.h>
35
36#include "md.h"
37#include "raid1.h"
38#include "md-bitmap.h"
39
40#define UNSUPPORTED_MDDEV_FLAGS \
41 ((1L << MD_HAS_JOURNAL) | \
42 (1L << MD_JOURNAL_CLEAN) | \
43 (1L << MD_HAS_PPL) | \
44 (1L << MD_HAS_MULTIPLE_PPLS))
45
46static void allow_barrier(struct r1conf *conf, sector_t sector_nr);
47static void lower_barrier(struct r1conf *conf, sector_t sector_nr);
48
49#define RAID_1_10_NAME "raid1"
50#include "raid1-10.c"
51
52#define START(node) ((node)->start)
53#define LAST(node) ((node)->last)
54INTERVAL_TREE_DEFINE(struct serial_info, node, sector_t, _subtree_last,
55 START, LAST, static inline, raid1_rb);
56
57static int check_and_add_serial(struct md_rdev *rdev, struct r1bio *r1_bio,
58 struct serial_info *si, int idx)
59{
60 unsigned long flags;
61 int ret = 0;
62 sector_t lo = r1_bio->sector;
63 sector_t hi = lo + r1_bio->sectors;
64 struct serial_in_rdev *serial = &rdev->serial[idx];
65
66 spin_lock_irqsave(&serial->serial_lock, flags);
67 /* collision happened */
68 if (raid1_rb_iter_first(&serial->serial_rb, lo, hi))
69 ret = -EBUSY;
70 else {
71 si->start = lo;
72 si->last = hi;
73 raid1_rb_insert(si, &serial->serial_rb);
74 }
75 spin_unlock_irqrestore(&serial->serial_lock, flags);
76
77 return ret;
78}
79
80static void wait_for_serialization(struct md_rdev *rdev, struct r1bio *r1_bio)
81{
82 struct mddev *mddev = rdev->mddev;
83 struct serial_info *si;
84 int idx = sector_to_idx(r1_bio->sector);
85 struct serial_in_rdev *serial = &rdev->serial[idx];
86
87 if (WARN_ON(!mddev->serial_info_pool))
88 return;
89 si = mempool_alloc(mddev->serial_info_pool, GFP_NOIO);
90 wait_event(serial->serial_io_wait,
91 check_and_add_serial(rdev, r1_bio, si, idx) == 0);
92}
93
94static void remove_serial(struct md_rdev *rdev, sector_t lo, sector_t hi)
95{
96 struct serial_info *si;
97 unsigned long flags;
98 int found = 0;
99 struct mddev *mddev = rdev->mddev;
100 int idx = sector_to_idx(lo);
101 struct serial_in_rdev *serial = &rdev->serial[idx];
102
103 spin_lock_irqsave(&serial->serial_lock, flags);
104 for (si = raid1_rb_iter_first(&serial->serial_rb, lo, hi);
105 si; si = raid1_rb_iter_next(si, lo, hi)) {
106 if (si->start == lo && si->last == hi) {
107 raid1_rb_remove(si, &serial->serial_rb);
108 mempool_free(si, mddev->serial_info_pool);
109 found = 1;
110 break;
111 }
112 }
113 if (!found)
114 WARN(1, "The write IO is not recorded for serialization\n");
115 spin_unlock_irqrestore(&serial->serial_lock, flags);
116 wake_up(&serial->serial_io_wait);
117}
118
119/*
120 * for resync bio, r1bio pointer can be retrieved from the per-bio
121 * 'struct resync_pages'.
122 */
123static inline struct r1bio *get_resync_r1bio(struct bio *bio)
124{
125 return get_resync_pages(bio)->raid_bio;
126}
127
128static void * r1bio_pool_alloc(gfp_t gfp_flags, void *data)
129{
130 struct pool_info *pi = data;
131 int size = offsetof(struct r1bio, bios[pi->raid_disks]);
132
133 /* allocate a r1bio with room for raid_disks entries in the bios array */
134 return kzalloc(size, gfp_flags);
135}
136
137#define RESYNC_DEPTH 32
138#define RESYNC_SECTORS (RESYNC_BLOCK_SIZE >> 9)
139#define RESYNC_WINDOW (RESYNC_BLOCK_SIZE * RESYNC_DEPTH)
140#define RESYNC_WINDOW_SECTORS (RESYNC_WINDOW >> 9)
141#define CLUSTER_RESYNC_WINDOW (16 * RESYNC_WINDOW)
142#define CLUSTER_RESYNC_WINDOW_SECTORS (CLUSTER_RESYNC_WINDOW >> 9)
143
144static void * r1buf_pool_alloc(gfp_t gfp_flags, void *data)
145{
146 struct pool_info *pi = data;
147 struct r1bio *r1_bio;
148 struct bio *bio;
149 int need_pages;
150 int j;
151 struct resync_pages *rps;
152
153 r1_bio = r1bio_pool_alloc(gfp_flags, pi);
154 if (!r1_bio)
155 return NULL;
156
157 rps = kmalloc_array(pi->raid_disks, sizeof(struct resync_pages),
158 gfp_flags);
159 if (!rps)
160 goto out_free_r1bio;
161
162 /*
163 * Allocate bios : 1 for reading, n-1 for writing
164 */
165 for (j = pi->raid_disks ; j-- ; ) {
166 bio = bio_kmalloc(RESYNC_PAGES, gfp_flags);
167 if (!bio)
168 goto out_free_bio;
169 bio_init(bio, NULL, bio->bi_inline_vecs, RESYNC_PAGES, 0);
170 r1_bio->bios[j] = bio;
171 }
172 /*
173 * Allocate RESYNC_PAGES data pages and attach them to
174 * the first bio.
175 * If this is a user-requested check/repair, allocate
176 * RESYNC_PAGES for each bio.
177 */
178 if (test_bit(MD_RECOVERY_REQUESTED, &pi->mddev->recovery))
179 need_pages = pi->raid_disks;
180 else
181 need_pages = 1;
182 for (j = 0; j < pi->raid_disks; j++) {
183 struct resync_pages *rp = &rps[j];
184
185 bio = r1_bio->bios[j];
186
187 if (j < need_pages) {
188 if (resync_alloc_pages(rp, gfp_flags))
189 goto out_free_pages;
190 } else {
191 memcpy(rp, &rps[0], sizeof(*rp));
192 resync_get_all_pages(rp);
193 }
194
195 rp->raid_bio = r1_bio;
196 bio->bi_private = rp;
197 }
198
199 r1_bio->master_bio = NULL;
200
201 return r1_bio;
202
203out_free_pages:
204 while (--j >= 0)
205 resync_free_pages(&rps[j]);
206
207out_free_bio:
208 while (++j < pi->raid_disks) {
209 bio_uninit(r1_bio->bios[j]);
210 kfree(r1_bio->bios[j]);
211 }
212 kfree(rps);
213
214out_free_r1bio:
215 rbio_pool_free(r1_bio, data);
216 return NULL;
217}
218
219static void r1buf_pool_free(void *__r1_bio, void *data)
220{
221 struct pool_info *pi = data;
222 int i;
223 struct r1bio *r1bio = __r1_bio;
224 struct resync_pages *rp = NULL;
225
226 for (i = pi->raid_disks; i--; ) {
227 rp = get_resync_pages(r1bio->bios[i]);
228 resync_free_pages(rp);
229 bio_uninit(r1bio->bios[i]);
230 kfree(r1bio->bios[i]);
231 }
232
233 /* resync pages array stored in the 1st bio's .bi_private */
234 kfree(rp);
235
236 rbio_pool_free(r1bio, data);
237}
238
239static void put_all_bios(struct r1conf *conf, struct r1bio *r1_bio)
240{
241 int i;
242
243 for (i = 0; i < conf->raid_disks * 2; i++) {
244 struct bio **bio = r1_bio->bios + i;
245 if (!BIO_SPECIAL(*bio))
246 bio_put(*bio);
247 *bio = NULL;
248 }
249}
250
251static void free_r1bio(struct r1bio *r1_bio)
252{
253 struct r1conf *conf = r1_bio->mddev->private;
254
255 put_all_bios(conf, r1_bio);
256 mempool_free(r1_bio, &conf->r1bio_pool);
257}
258
259static void put_buf(struct r1bio *r1_bio)
260{
261 struct r1conf *conf = r1_bio->mddev->private;
262 sector_t sect = r1_bio->sector;
263 int i;
264
265 for (i = 0; i < conf->raid_disks * 2; i++) {
266 struct bio *bio = r1_bio->bios[i];
267 if (bio->bi_end_io)
268 rdev_dec_pending(conf->mirrors[i].rdev, r1_bio->mddev);
269 }
270
271 mempool_free(r1_bio, &conf->r1buf_pool);
272
273 lower_barrier(conf, sect);
274}
275
276static void reschedule_retry(struct r1bio *r1_bio)
277{
278 unsigned long flags;
279 struct mddev *mddev = r1_bio->mddev;
280 struct r1conf *conf = mddev->private;
281 int idx;
282
283 idx = sector_to_idx(r1_bio->sector);
284 spin_lock_irqsave(&conf->device_lock, flags);
285 list_add(&r1_bio->retry_list, &conf->retry_list);
286 atomic_inc(&conf->nr_queued[idx]);
287 spin_unlock_irqrestore(&conf->device_lock, flags);
288
289 wake_up(&conf->wait_barrier);
290 md_wakeup_thread(mddev->thread);
291}
292
293/*
294 * raid_end_bio_io() is called when we have finished servicing a mirrored
295 * operation and are ready to return a success/failure code to the buffer
296 * cache layer.
297 */
298static void call_bio_endio(struct r1bio *r1_bio)
299{
300 struct bio *bio = r1_bio->master_bio;
301
302 if (!test_bit(R1BIO_Uptodate, &r1_bio->state))
303 bio->bi_status = BLK_STS_IOERR;
304
305 bio_endio(bio);
306}
307
308static void raid_end_bio_io(struct r1bio *r1_bio)
309{
310 struct bio *bio = r1_bio->master_bio;
311 struct r1conf *conf = r1_bio->mddev->private;
312 sector_t sector = r1_bio->sector;
313
314 /* if nobody has done the final endio yet, do it now */
315 if (!test_and_set_bit(R1BIO_Returned, &r1_bio->state)) {
316 pr_debug("raid1: sync end %s on sectors %llu-%llu\n",
317 (bio_data_dir(bio) == WRITE) ? "write" : "read",
318 (unsigned long long) bio->bi_iter.bi_sector,
319 (unsigned long long) bio_end_sector(bio) - 1);
320
321 call_bio_endio(r1_bio);
322 }
323
324 free_r1bio(r1_bio);
325 /*
326 * Wake up any possible resync thread that waits for the device
327 * to go idle. All I/Os, even write-behind writes, are done.
328 */
329 allow_barrier(conf, sector);
330}
331
332/*
333 * Update disk head position estimator based on IRQ completion info.
334 */
335static inline void update_head_pos(int disk, struct r1bio *r1_bio)
336{
337 struct r1conf *conf = r1_bio->mddev->private;
338
339 conf->mirrors[disk].head_position =
340 r1_bio->sector + (r1_bio->sectors);
341}
342
343/*
344 * Find the disk number which triggered given bio
345 */
346static int find_bio_disk(struct r1bio *r1_bio, struct bio *bio)
347{
348 int mirror;
349 struct r1conf *conf = r1_bio->mddev->private;
350 int raid_disks = conf->raid_disks;
351
352 for (mirror = 0; mirror < raid_disks * 2; mirror++)
353 if (r1_bio->bios[mirror] == bio)
354 break;
355
356 BUG_ON(mirror == raid_disks * 2);
357 update_head_pos(mirror, r1_bio);
358
359 return mirror;
360}
361
362static void raid1_end_read_request(struct bio *bio)
363{
364 int uptodate = !bio->bi_status;
365 struct r1bio *r1_bio = bio->bi_private;
366 struct r1conf *conf = r1_bio->mddev->private;
367 struct md_rdev *rdev = conf->mirrors[r1_bio->read_disk].rdev;
368
369 /*
370 * this branch is our 'one mirror IO has finished' event handler:
371 */
372 update_head_pos(r1_bio->read_disk, r1_bio);
373
374 if (uptodate)
375 set_bit(R1BIO_Uptodate, &r1_bio->state);
376 else if (test_bit(FailFast, &rdev->flags) &&
377 test_bit(R1BIO_FailFast, &r1_bio->state))
378 /* This was a fail-fast read so we definitely
379 * want to retry */
380 ;
381 else {
382 /* If all other devices have failed, we want to return
383 * the error upwards rather than fail the last device.
384 * Here we redefine "uptodate" to mean "Don't want to retry"
385 */
386 unsigned long flags;
387 spin_lock_irqsave(&conf->device_lock, flags);
388 if (r1_bio->mddev->degraded == conf->raid_disks ||
389 (r1_bio->mddev->degraded == conf->raid_disks-1 &&
390 test_bit(In_sync, &rdev->flags)))
391 uptodate = 1;
392 spin_unlock_irqrestore(&conf->device_lock, flags);
393 }
394
395 if (uptodate) {
396 raid_end_bio_io(r1_bio);
397 rdev_dec_pending(rdev, conf->mddev);
398 } else {
399 /*
400 * oops, read error:
401 */
402 pr_err_ratelimited("md/raid1:%s: %pg: rescheduling sector %llu\n",
403 mdname(conf->mddev),
404 rdev->bdev,
405 (unsigned long long)r1_bio->sector);
406 set_bit(R1BIO_ReadError, &r1_bio->state);
407 reschedule_retry(r1_bio);
408 /* don't drop the reference on read_disk yet */
409 }
410}
411
412static void close_write(struct r1bio *r1_bio)
413{
414 /* it really is the end of this request */
415 if (test_bit(R1BIO_BehindIO, &r1_bio->state)) {
416 bio_free_pages(r1_bio->behind_master_bio);
417 bio_put(r1_bio->behind_master_bio);
418 r1_bio->behind_master_bio = NULL;
419 }
420 /* clear the bitmap if all writes complete successfully */
421 md_bitmap_endwrite(r1_bio->mddev->bitmap, r1_bio->sector,
422 r1_bio->sectors,
423 !test_bit(R1BIO_Degraded, &r1_bio->state),
424 test_bit(R1BIO_BehindIO, &r1_bio->state));
425 md_write_end(r1_bio->mddev);
426}
427
428static void r1_bio_write_done(struct r1bio *r1_bio)
429{
430 if (!atomic_dec_and_test(&r1_bio->remaining))
431 return;
432
433 if (test_bit(R1BIO_WriteError, &r1_bio->state))
434 reschedule_retry(r1_bio);
435 else {
436 close_write(r1_bio);
437 if (test_bit(R1BIO_MadeGood, &r1_bio->state))
438 reschedule_retry(r1_bio);
439 else
440 raid_end_bio_io(r1_bio);
441 }
442}
443
444static void raid1_end_write_request(struct bio *bio)
445{
446 struct r1bio *r1_bio = bio->bi_private;
447 int behind = test_bit(R1BIO_BehindIO, &r1_bio->state);
448 struct r1conf *conf = r1_bio->mddev->private;
449 struct bio *to_put = NULL;
450 int mirror = find_bio_disk(r1_bio, bio);
451 struct md_rdev *rdev = conf->mirrors[mirror].rdev;
452 bool discard_error;
453 sector_t lo = r1_bio->sector;
454 sector_t hi = r1_bio->sector + r1_bio->sectors;
455
456 discard_error = bio->bi_status && bio_op(bio) == REQ_OP_DISCARD;
457
458 /*
459 * 'one mirror IO has finished' event handler:
460 */
461 if (bio->bi_status && !discard_error) {
462 set_bit(WriteErrorSeen, &rdev->flags);
463 if (!test_and_set_bit(WantReplacement, &rdev->flags))
464 set_bit(MD_RECOVERY_NEEDED, &
465 conf->mddev->recovery);
466
467 if (test_bit(FailFast, &rdev->flags) &&
468 (bio->bi_opf & MD_FAILFAST) &&
469 /* We never try FailFast to WriteMostly devices */
470 !test_bit(WriteMostly, &rdev->flags)) {
471 md_error(r1_bio->mddev, rdev);
472 }
473
474 /*
475 * When the device is faulty, it is not necessary to
476 * handle write error.
477 */
478 if (!test_bit(Faulty, &rdev->flags))
479 set_bit(R1BIO_WriteError, &r1_bio->state);
480 else {
481 /* Fail the request */
482 set_bit(R1BIO_Degraded, &r1_bio->state);
483 /* Finished with this branch */
484 r1_bio->bios[mirror] = NULL;
485 to_put = bio;
486 }
487 } else {
488 /*
489 * Set R1BIO_Uptodate in our master bio, so that we
490 * will return a good error code for to the higher
491 * levels even if IO on some other mirrored buffer
492 * fails.
493 *
494 * The 'master' represents the composite IO operation
495 * to user-side. So if something waits for IO, then it
496 * will wait for the 'master' bio.
497 */
498 r1_bio->bios[mirror] = NULL;
499 to_put = bio;
500 /*
501 * Do not set R1BIO_Uptodate if the current device is
502 * rebuilding or Faulty. This is because we cannot use
503 * such device for properly reading the data back (we could
504 * potentially use it, if the current write would have felt
505 * before rdev->recovery_offset, but for simplicity we don't
506 * check this here.
507 */
508 if (test_bit(In_sync, &rdev->flags) &&
509 !test_bit(Faulty, &rdev->flags))
510 set_bit(R1BIO_Uptodate, &r1_bio->state);
511
512 /* Maybe we can clear some bad blocks. */
513 if (rdev_has_badblock(rdev, r1_bio->sector, r1_bio->sectors) &&
514 !discard_error) {
515 r1_bio->bios[mirror] = IO_MADE_GOOD;
516 set_bit(R1BIO_MadeGood, &r1_bio->state);
517 }
518 }
519
520 if (behind) {
521 if (test_bit(CollisionCheck, &rdev->flags))
522 remove_serial(rdev, lo, hi);
523 if (test_bit(WriteMostly, &rdev->flags))
524 atomic_dec(&r1_bio->behind_remaining);
525
526 /*
527 * In behind mode, we ACK the master bio once the I/O
528 * has safely reached all non-writemostly
529 * disks. Setting the Returned bit ensures that this
530 * gets done only once -- we don't ever want to return
531 * -EIO here, instead we'll wait
532 */
533 if (atomic_read(&r1_bio->behind_remaining) >= (atomic_read(&r1_bio->remaining)-1) &&
534 test_bit(R1BIO_Uptodate, &r1_bio->state)) {
535 /* Maybe we can return now */
536 if (!test_and_set_bit(R1BIO_Returned, &r1_bio->state)) {
537 struct bio *mbio = r1_bio->master_bio;
538 pr_debug("raid1: behind end write sectors"
539 " %llu-%llu\n",
540 (unsigned long long) mbio->bi_iter.bi_sector,
541 (unsigned long long) bio_end_sector(mbio) - 1);
542 call_bio_endio(r1_bio);
543 }
544 }
545 } else if (rdev->mddev->serialize_policy)
546 remove_serial(rdev, lo, hi);
547 if (r1_bio->bios[mirror] == NULL)
548 rdev_dec_pending(rdev, conf->mddev);
549
550 /*
551 * Let's see if all mirrored write operations have finished
552 * already.
553 */
554 r1_bio_write_done(r1_bio);
555
556 if (to_put)
557 bio_put(to_put);
558}
559
560static sector_t align_to_barrier_unit_end(sector_t start_sector,
561 sector_t sectors)
562{
563 sector_t len;
564
565 WARN_ON(sectors == 0);
566 /*
567 * len is the number of sectors from start_sector to end of the
568 * barrier unit which start_sector belongs to.
569 */
570 len = round_up(start_sector + 1, BARRIER_UNIT_SECTOR_SIZE) -
571 start_sector;
572
573 if (len > sectors)
574 len = sectors;
575
576 return len;
577}
578
579static void update_read_sectors(struct r1conf *conf, int disk,
580 sector_t this_sector, int len)
581{
582 struct raid1_info *info = &conf->mirrors[disk];
583
584 atomic_inc(&info->rdev->nr_pending);
585 if (info->next_seq_sect != this_sector)
586 info->seq_start = this_sector;
587 info->next_seq_sect = this_sector + len;
588}
589
590static int choose_first_rdev(struct r1conf *conf, struct r1bio *r1_bio,
591 int *max_sectors)
592{
593 sector_t this_sector = r1_bio->sector;
594 int len = r1_bio->sectors;
595 int disk;
596
597 for (disk = 0 ; disk < conf->raid_disks * 2 ; disk++) {
598 struct md_rdev *rdev;
599 int read_len;
600
601 if (r1_bio->bios[disk] == IO_BLOCKED)
602 continue;
603
604 rdev = conf->mirrors[disk].rdev;
605 if (!rdev || test_bit(Faulty, &rdev->flags))
606 continue;
607
608 /* choose the first disk even if it has some bad blocks. */
609 read_len = raid1_check_read_range(rdev, this_sector, &len);
610 if (read_len > 0) {
611 update_read_sectors(conf, disk, this_sector, read_len);
612 *max_sectors = read_len;
613 return disk;
614 }
615 }
616
617 return -1;
618}
619
620static int choose_bb_rdev(struct r1conf *conf, struct r1bio *r1_bio,
621 int *max_sectors)
622{
623 sector_t this_sector = r1_bio->sector;
624 int best_disk = -1;
625 int best_len = 0;
626 int disk;
627
628 for (disk = 0 ; disk < conf->raid_disks * 2 ; disk++) {
629 struct md_rdev *rdev;
630 int len;
631 int read_len;
632
633 if (r1_bio->bios[disk] == IO_BLOCKED)
634 continue;
635
636 rdev = conf->mirrors[disk].rdev;
637 if (!rdev || test_bit(Faulty, &rdev->flags) ||
638 test_bit(WriteMostly, &rdev->flags))
639 continue;
640
641 /* keep track of the disk with the most readable sectors. */
642 len = r1_bio->sectors;
643 read_len = raid1_check_read_range(rdev, this_sector, &len);
644 if (read_len > best_len) {
645 best_disk = disk;
646 best_len = read_len;
647 }
648 }
649
650 if (best_disk != -1) {
651 *max_sectors = best_len;
652 update_read_sectors(conf, best_disk, this_sector, best_len);
653 }
654
655 return best_disk;
656}
657
658static int choose_slow_rdev(struct r1conf *conf, struct r1bio *r1_bio,
659 int *max_sectors)
660{
661 sector_t this_sector = r1_bio->sector;
662 int bb_disk = -1;
663 int bb_read_len = 0;
664 int disk;
665
666 for (disk = 0 ; disk < conf->raid_disks * 2 ; disk++) {
667 struct md_rdev *rdev;
668 int len;
669 int read_len;
670
671 if (r1_bio->bios[disk] == IO_BLOCKED)
672 continue;
673
674 rdev = conf->mirrors[disk].rdev;
675 if (!rdev || test_bit(Faulty, &rdev->flags) ||
676 !test_bit(WriteMostly, &rdev->flags))
677 continue;
678
679 /* there are no bad blocks, we can use this disk */
680 len = r1_bio->sectors;
681 read_len = raid1_check_read_range(rdev, this_sector, &len);
682 if (read_len == r1_bio->sectors) {
683 update_read_sectors(conf, disk, this_sector, read_len);
684 return disk;
685 }
686
687 /*
688 * there are partial bad blocks, choose the rdev with largest
689 * read length.
690 */
691 if (read_len > bb_read_len) {
692 bb_disk = disk;
693 bb_read_len = read_len;
694 }
695 }
696
697 if (bb_disk != -1) {
698 *max_sectors = bb_read_len;
699 update_read_sectors(conf, bb_disk, this_sector, bb_read_len);
700 }
701
702 return bb_disk;
703}
704
705static bool is_sequential(struct r1conf *conf, int disk, struct r1bio *r1_bio)
706{
707 /* TODO: address issues with this check and concurrency. */
708 return conf->mirrors[disk].next_seq_sect == r1_bio->sector ||
709 conf->mirrors[disk].head_position == r1_bio->sector;
710}
711
712/*
713 * If buffered sequential IO size exceeds optimal iosize, check if there is idle
714 * disk. If yes, choose the idle disk.
715 */
716static bool should_choose_next(struct r1conf *conf, int disk)
717{
718 struct raid1_info *mirror = &conf->mirrors[disk];
719 int opt_iosize;
720
721 if (!test_bit(Nonrot, &mirror->rdev->flags))
722 return false;
723
724 opt_iosize = bdev_io_opt(mirror->rdev->bdev) >> 9;
725 return opt_iosize > 0 && mirror->seq_start != MaxSector &&
726 mirror->next_seq_sect > opt_iosize &&
727 mirror->next_seq_sect - opt_iosize >= mirror->seq_start;
728}
729
730static bool rdev_readable(struct md_rdev *rdev, struct r1bio *r1_bio)
731{
732 if (!rdev || test_bit(Faulty, &rdev->flags))
733 return false;
734
735 /* still in recovery */
736 if (!test_bit(In_sync, &rdev->flags) &&
737 rdev->recovery_offset < r1_bio->sector + r1_bio->sectors)
738 return false;
739
740 /* don't read from slow disk unless have to */
741 if (test_bit(WriteMostly, &rdev->flags))
742 return false;
743
744 /* don't split IO for bad blocks unless have to */
745 if (rdev_has_badblock(rdev, r1_bio->sector, r1_bio->sectors))
746 return false;
747
748 return true;
749}
750
751struct read_balance_ctl {
752 sector_t closest_dist;
753 int closest_dist_disk;
754 int min_pending;
755 int min_pending_disk;
756 int sequential_disk;
757 int readable_disks;
758};
759
760static int choose_best_rdev(struct r1conf *conf, struct r1bio *r1_bio)
761{
762 int disk;
763 struct read_balance_ctl ctl = {
764 .closest_dist_disk = -1,
765 .closest_dist = MaxSector,
766 .min_pending_disk = -1,
767 .min_pending = UINT_MAX,
768 .sequential_disk = -1,
769 };
770
771 for (disk = 0 ; disk < conf->raid_disks * 2 ; disk++) {
772 struct md_rdev *rdev;
773 sector_t dist;
774 unsigned int pending;
775
776 if (r1_bio->bios[disk] == IO_BLOCKED)
777 continue;
778
779 rdev = conf->mirrors[disk].rdev;
780 if (!rdev_readable(rdev, r1_bio))
781 continue;
782
783 /* At least two disks to choose from so failfast is OK */
784 if (ctl.readable_disks++ == 1)
785 set_bit(R1BIO_FailFast, &r1_bio->state);
786
787 pending = atomic_read(&rdev->nr_pending);
788 dist = abs(r1_bio->sector - conf->mirrors[disk].head_position);
789
790 /* Don't change to another disk for sequential reads */
791 if (is_sequential(conf, disk, r1_bio)) {
792 if (!should_choose_next(conf, disk))
793 return disk;
794
795 /*
796 * Add 'pending' to avoid choosing this disk if
797 * there is other idle disk.
798 */
799 pending++;
800 /*
801 * If there is no other idle disk, this disk
802 * will be chosen.
803 */
804 ctl.sequential_disk = disk;
805 }
806
807 if (ctl.min_pending > pending) {
808 ctl.min_pending = pending;
809 ctl.min_pending_disk = disk;
810 }
811
812 if (ctl.closest_dist > dist) {
813 ctl.closest_dist = dist;
814 ctl.closest_dist_disk = disk;
815 }
816 }
817
818 /*
819 * sequential IO size exceeds optimal iosize, however, there is no other
820 * idle disk, so choose the sequential disk.
821 */
822 if (ctl.sequential_disk != -1 && ctl.min_pending != 0)
823 return ctl.sequential_disk;
824
825 /*
826 * If all disks are rotational, choose the closest disk. If any disk is
827 * non-rotational, choose the disk with less pending request even the
828 * disk is rotational, which might/might not be optimal for raids with
829 * mixed ratation/non-rotational disks depending on workload.
830 */
831 if (ctl.min_pending_disk != -1 &&
832 (READ_ONCE(conf->nonrot_disks) || ctl.min_pending == 0))
833 return ctl.min_pending_disk;
834 else
835 return ctl.closest_dist_disk;
836}
837
838/*
839 * This routine returns the disk from which the requested read should be done.
840 *
841 * 1) If resync is in progress, find the first usable disk and use it even if it
842 * has some bad blocks.
843 *
844 * 2) Now that there is no resync, loop through all disks and skipping slow
845 * disks and disks with bad blocks for now. Only pay attention to key disk
846 * choice.
847 *
848 * 3) If we've made it this far, now look for disks with bad blocks and choose
849 * the one with most number of sectors.
850 *
851 * 4) If we are all the way at the end, we have no choice but to use a disk even
852 * if it is write mostly.
853 *
854 * The rdev for the device selected will have nr_pending incremented.
855 */
856static int read_balance(struct r1conf *conf, struct r1bio *r1_bio,
857 int *max_sectors)
858{
859 int disk;
860
861 clear_bit(R1BIO_FailFast, &r1_bio->state);
862
863 if (raid1_should_read_first(conf->mddev, r1_bio->sector,
864 r1_bio->sectors))
865 return choose_first_rdev(conf, r1_bio, max_sectors);
866
867 disk = choose_best_rdev(conf, r1_bio);
868 if (disk >= 0) {
869 *max_sectors = r1_bio->sectors;
870 update_read_sectors(conf, disk, r1_bio->sector,
871 r1_bio->sectors);
872 return disk;
873 }
874
875 /*
876 * If we are here it means we didn't find a perfectly good disk so
877 * now spend a bit more time trying to find one with the most good
878 * sectors.
879 */
880 disk = choose_bb_rdev(conf, r1_bio, max_sectors);
881 if (disk >= 0)
882 return disk;
883
884 return choose_slow_rdev(conf, r1_bio, max_sectors);
885}
886
887static void wake_up_barrier(struct r1conf *conf)
888{
889 if (wq_has_sleeper(&conf->wait_barrier))
890 wake_up(&conf->wait_barrier);
891}
892
893static void flush_bio_list(struct r1conf *conf, struct bio *bio)
894{
895 /* flush any pending bitmap writes to disk before proceeding w/ I/O */
896 raid1_prepare_flush_writes(conf->mddev->bitmap);
897 wake_up_barrier(conf);
898
899 while (bio) { /* submit pending writes */
900 struct bio *next = bio->bi_next;
901
902 raid1_submit_write(bio);
903 bio = next;
904 cond_resched();
905 }
906}
907
908static void flush_pending_writes(struct r1conf *conf)
909{
910 /* Any writes that have been queued but are awaiting
911 * bitmap updates get flushed here.
912 */
913 spin_lock_irq(&conf->device_lock);
914
915 if (conf->pending_bio_list.head) {
916 struct blk_plug plug;
917 struct bio *bio;
918
919 bio = bio_list_get(&conf->pending_bio_list);
920 spin_unlock_irq(&conf->device_lock);
921
922 /*
923 * As this is called in a wait_event() loop (see freeze_array),
924 * current->state might be TASK_UNINTERRUPTIBLE which will
925 * cause a warning when we prepare to wait again. As it is
926 * rare that this path is taken, it is perfectly safe to force
927 * us to go around the wait_event() loop again, so the warning
928 * is a false-positive. Silence the warning by resetting
929 * thread state
930 */
931 __set_current_state(TASK_RUNNING);
932 blk_start_plug(&plug);
933 flush_bio_list(conf, bio);
934 blk_finish_plug(&plug);
935 } else
936 spin_unlock_irq(&conf->device_lock);
937}
938
939/* Barriers....
940 * Sometimes we need to suspend IO while we do something else,
941 * either some resync/recovery, or reconfigure the array.
942 * To do this we raise a 'barrier'.
943 * The 'barrier' is a counter that can be raised multiple times
944 * to count how many activities are happening which preclude
945 * normal IO.
946 * We can only raise the barrier if there is no pending IO.
947 * i.e. if nr_pending == 0.
948 * We choose only to raise the barrier if no-one is waiting for the
949 * barrier to go down. This means that as soon as an IO request
950 * is ready, no other operations which require a barrier will start
951 * until the IO request has had a chance.
952 *
953 * So: regular IO calls 'wait_barrier'. When that returns there
954 * is no backgroup IO happening, It must arrange to call
955 * allow_barrier when it has finished its IO.
956 * backgroup IO calls must call raise_barrier. Once that returns
957 * there is no normal IO happeing. It must arrange to call
958 * lower_barrier when the particular background IO completes.
959 *
960 * If resync/recovery is interrupted, returns -EINTR;
961 * Otherwise, returns 0.
962 */
963static int raise_barrier(struct r1conf *conf, sector_t sector_nr)
964{
965 int idx = sector_to_idx(sector_nr);
966
967 spin_lock_irq(&conf->resync_lock);
968
969 /* Wait until no block IO is waiting */
970 wait_event_lock_irq(conf->wait_barrier,
971 !atomic_read(&conf->nr_waiting[idx]),
972 conf->resync_lock);
973
974 /* block any new IO from starting */
975 atomic_inc(&conf->barrier[idx]);
976 /*
977 * In raise_barrier() we firstly increase conf->barrier[idx] then
978 * check conf->nr_pending[idx]. In _wait_barrier() we firstly
979 * increase conf->nr_pending[idx] then check conf->barrier[idx].
980 * A memory barrier here to make sure conf->nr_pending[idx] won't
981 * be fetched before conf->barrier[idx] is increased. Otherwise
982 * there will be a race between raise_barrier() and _wait_barrier().
983 */
984 smp_mb__after_atomic();
985
986 /* For these conditions we must wait:
987 * A: while the array is in frozen state
988 * B: while conf->nr_pending[idx] is not 0, meaning regular I/O
989 * existing in corresponding I/O barrier bucket.
990 * C: while conf->barrier[idx] >= RESYNC_DEPTH, meaning reaches
991 * max resync count which allowed on current I/O barrier bucket.
992 */
993 wait_event_lock_irq(conf->wait_barrier,
994 (!conf->array_frozen &&
995 !atomic_read(&conf->nr_pending[idx]) &&
996 atomic_read(&conf->barrier[idx]) < RESYNC_DEPTH) ||
997 test_bit(MD_RECOVERY_INTR, &conf->mddev->recovery),
998 conf->resync_lock);
999
1000 if (test_bit(MD_RECOVERY_INTR, &conf->mddev->recovery)) {
1001 atomic_dec(&conf->barrier[idx]);
1002 spin_unlock_irq(&conf->resync_lock);
1003 wake_up(&conf->wait_barrier);
1004 return -EINTR;
1005 }
1006
1007 atomic_inc(&conf->nr_sync_pending);
1008 spin_unlock_irq(&conf->resync_lock);
1009
1010 return 0;
1011}
1012
1013static void lower_barrier(struct r1conf *conf, sector_t sector_nr)
1014{
1015 int idx = sector_to_idx(sector_nr);
1016
1017 BUG_ON(atomic_read(&conf->barrier[idx]) <= 0);
1018
1019 atomic_dec(&conf->barrier[idx]);
1020 atomic_dec(&conf->nr_sync_pending);
1021 wake_up(&conf->wait_barrier);
1022}
1023
1024static bool _wait_barrier(struct r1conf *conf, int idx, bool nowait)
1025{
1026 bool ret = true;
1027
1028 /*
1029 * We need to increase conf->nr_pending[idx] very early here,
1030 * then raise_barrier() can be blocked when it waits for
1031 * conf->nr_pending[idx] to be 0. Then we can avoid holding
1032 * conf->resync_lock when there is no barrier raised in same
1033 * barrier unit bucket. Also if the array is frozen, I/O
1034 * should be blocked until array is unfrozen.
1035 */
1036 atomic_inc(&conf->nr_pending[idx]);
1037 /*
1038 * In _wait_barrier() we firstly increase conf->nr_pending[idx], then
1039 * check conf->barrier[idx]. In raise_barrier() we firstly increase
1040 * conf->barrier[idx], then check conf->nr_pending[idx]. A memory
1041 * barrier is necessary here to make sure conf->barrier[idx] won't be
1042 * fetched before conf->nr_pending[idx] is increased. Otherwise there
1043 * will be a race between _wait_barrier() and raise_barrier().
1044 */
1045 smp_mb__after_atomic();
1046
1047 /*
1048 * Don't worry about checking two atomic_t variables at same time
1049 * here. If during we check conf->barrier[idx], the array is
1050 * frozen (conf->array_frozen is 1), and chonf->barrier[idx] is
1051 * 0, it is safe to return and make the I/O continue. Because the
1052 * array is frozen, all I/O returned here will eventually complete
1053 * or be queued, no race will happen. See code comment in
1054 * frozen_array().
1055 */
1056 if (!READ_ONCE(conf->array_frozen) &&
1057 !atomic_read(&conf->barrier[idx]))
1058 return ret;
1059
1060 /*
1061 * After holding conf->resync_lock, conf->nr_pending[idx]
1062 * should be decreased before waiting for barrier to drop.
1063 * Otherwise, we may encounter a race condition because
1064 * raise_barrer() might be waiting for conf->nr_pending[idx]
1065 * to be 0 at same time.
1066 */
1067 spin_lock_irq(&conf->resync_lock);
1068 atomic_inc(&conf->nr_waiting[idx]);
1069 atomic_dec(&conf->nr_pending[idx]);
1070 /*
1071 * In case freeze_array() is waiting for
1072 * get_unqueued_pending() == extra
1073 */
1074 wake_up_barrier(conf);
1075 /* Wait for the barrier in same barrier unit bucket to drop. */
1076
1077 /* Return false when nowait flag is set */
1078 if (nowait) {
1079 ret = false;
1080 } else {
1081 wait_event_lock_irq(conf->wait_barrier,
1082 !conf->array_frozen &&
1083 !atomic_read(&conf->barrier[idx]),
1084 conf->resync_lock);
1085 atomic_inc(&conf->nr_pending[idx]);
1086 }
1087
1088 atomic_dec(&conf->nr_waiting[idx]);
1089 spin_unlock_irq(&conf->resync_lock);
1090 return ret;
1091}
1092
1093static bool wait_read_barrier(struct r1conf *conf, sector_t sector_nr, bool nowait)
1094{
1095 int idx = sector_to_idx(sector_nr);
1096 bool ret = true;
1097
1098 /*
1099 * Very similar to _wait_barrier(). The difference is, for read
1100 * I/O we don't need wait for sync I/O, but if the whole array
1101 * is frozen, the read I/O still has to wait until the array is
1102 * unfrozen. Since there is no ordering requirement with
1103 * conf->barrier[idx] here, memory barrier is unnecessary as well.
1104 */
1105 atomic_inc(&conf->nr_pending[idx]);
1106
1107 if (!READ_ONCE(conf->array_frozen))
1108 return ret;
1109
1110 spin_lock_irq(&conf->resync_lock);
1111 atomic_inc(&conf->nr_waiting[idx]);
1112 atomic_dec(&conf->nr_pending[idx]);
1113 /*
1114 * In case freeze_array() is waiting for
1115 * get_unqueued_pending() == extra
1116 */
1117 wake_up_barrier(conf);
1118 /* Wait for array to be unfrozen */
1119
1120 /* Return false when nowait flag is set */
1121 if (nowait) {
1122 /* Return false when nowait flag is set */
1123 ret = false;
1124 } else {
1125 wait_event_lock_irq(conf->wait_barrier,
1126 !conf->array_frozen,
1127 conf->resync_lock);
1128 atomic_inc(&conf->nr_pending[idx]);
1129 }
1130
1131 atomic_dec(&conf->nr_waiting[idx]);
1132 spin_unlock_irq(&conf->resync_lock);
1133 return ret;
1134}
1135
1136static bool wait_barrier(struct r1conf *conf, sector_t sector_nr, bool nowait)
1137{
1138 int idx = sector_to_idx(sector_nr);
1139
1140 return _wait_barrier(conf, idx, nowait);
1141}
1142
1143static void _allow_barrier(struct r1conf *conf, int idx)
1144{
1145 atomic_dec(&conf->nr_pending[idx]);
1146 wake_up_barrier(conf);
1147}
1148
1149static void allow_barrier(struct r1conf *conf, sector_t sector_nr)
1150{
1151 int idx = sector_to_idx(sector_nr);
1152
1153 _allow_barrier(conf, idx);
1154}
1155
1156/* conf->resync_lock should be held */
1157static int get_unqueued_pending(struct r1conf *conf)
1158{
1159 int idx, ret;
1160
1161 ret = atomic_read(&conf->nr_sync_pending);
1162 for (idx = 0; idx < BARRIER_BUCKETS_NR; idx++)
1163 ret += atomic_read(&conf->nr_pending[idx]) -
1164 atomic_read(&conf->nr_queued[idx]);
1165
1166 return ret;
1167}
1168
1169static void freeze_array(struct r1conf *conf, int extra)
1170{
1171 /* Stop sync I/O and normal I/O and wait for everything to
1172 * go quiet.
1173 * This is called in two situations:
1174 * 1) management command handlers (reshape, remove disk, quiesce).
1175 * 2) one normal I/O request failed.
1176
1177 * After array_frozen is set to 1, new sync IO will be blocked at
1178 * raise_barrier(), and new normal I/O will blocked at _wait_barrier()
1179 * or wait_read_barrier(). The flying I/Os will either complete or be
1180 * queued. When everything goes quite, there are only queued I/Os left.
1181
1182 * Every flying I/O contributes to a conf->nr_pending[idx], idx is the
1183 * barrier bucket index which this I/O request hits. When all sync and
1184 * normal I/O are queued, sum of all conf->nr_pending[] will match sum
1185 * of all conf->nr_queued[]. But normal I/O failure is an exception,
1186 * in handle_read_error(), we may call freeze_array() before trying to
1187 * fix the read error. In this case, the error read I/O is not queued,
1188 * so get_unqueued_pending() == 1.
1189 *
1190 * Therefore before this function returns, we need to wait until
1191 * get_unqueued_pendings(conf) gets equal to extra. For
1192 * normal I/O context, extra is 1, in rested situations extra is 0.
1193 */
1194 spin_lock_irq(&conf->resync_lock);
1195 conf->array_frozen = 1;
1196 mddev_add_trace_msg(conf->mddev, "raid1 wait freeze");
1197 wait_event_lock_irq_cmd(
1198 conf->wait_barrier,
1199 get_unqueued_pending(conf) == extra,
1200 conf->resync_lock,
1201 flush_pending_writes(conf));
1202 spin_unlock_irq(&conf->resync_lock);
1203}
1204static void unfreeze_array(struct r1conf *conf)
1205{
1206 /* reverse the effect of the freeze */
1207 spin_lock_irq(&conf->resync_lock);
1208 conf->array_frozen = 0;
1209 spin_unlock_irq(&conf->resync_lock);
1210 wake_up(&conf->wait_barrier);
1211}
1212
1213static void alloc_behind_master_bio(struct r1bio *r1_bio,
1214 struct bio *bio)
1215{
1216 int size = bio->bi_iter.bi_size;
1217 unsigned vcnt = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
1218 int i = 0;
1219 struct bio *behind_bio = NULL;
1220
1221 behind_bio = bio_alloc_bioset(NULL, vcnt, 0, GFP_NOIO,
1222 &r1_bio->mddev->bio_set);
1223
1224 /* discard op, we don't support writezero/writesame yet */
1225 if (!bio_has_data(bio)) {
1226 behind_bio->bi_iter.bi_size = size;
1227 goto skip_copy;
1228 }
1229
1230 while (i < vcnt && size) {
1231 struct page *page;
1232 int len = min_t(int, PAGE_SIZE, size);
1233
1234 page = alloc_page(GFP_NOIO);
1235 if (unlikely(!page))
1236 goto free_pages;
1237
1238 if (!bio_add_page(behind_bio, page, len, 0)) {
1239 put_page(page);
1240 goto free_pages;
1241 }
1242
1243 size -= len;
1244 i++;
1245 }
1246
1247 bio_copy_data(behind_bio, bio);
1248skip_copy:
1249 r1_bio->behind_master_bio = behind_bio;
1250 set_bit(R1BIO_BehindIO, &r1_bio->state);
1251
1252 return;
1253
1254free_pages:
1255 pr_debug("%dB behind alloc failed, doing sync I/O\n",
1256 bio->bi_iter.bi_size);
1257 bio_free_pages(behind_bio);
1258 bio_put(behind_bio);
1259}
1260
1261static void raid1_unplug(struct blk_plug_cb *cb, bool from_schedule)
1262{
1263 struct raid1_plug_cb *plug = container_of(cb, struct raid1_plug_cb,
1264 cb);
1265 struct mddev *mddev = plug->cb.data;
1266 struct r1conf *conf = mddev->private;
1267 struct bio *bio;
1268
1269 if (from_schedule) {
1270 spin_lock_irq(&conf->device_lock);
1271 bio_list_merge(&conf->pending_bio_list, &plug->pending);
1272 spin_unlock_irq(&conf->device_lock);
1273 wake_up_barrier(conf);
1274 md_wakeup_thread(mddev->thread);
1275 kfree(plug);
1276 return;
1277 }
1278
1279 /* we aren't scheduling, so we can do the write-out directly. */
1280 bio = bio_list_get(&plug->pending);
1281 flush_bio_list(conf, bio);
1282 kfree(plug);
1283}
1284
1285static void init_r1bio(struct r1bio *r1_bio, struct mddev *mddev, struct bio *bio)
1286{
1287 r1_bio->master_bio = bio;
1288 r1_bio->sectors = bio_sectors(bio);
1289 r1_bio->state = 0;
1290 r1_bio->mddev = mddev;
1291 r1_bio->sector = bio->bi_iter.bi_sector;
1292}
1293
1294static inline struct r1bio *
1295alloc_r1bio(struct mddev *mddev, struct bio *bio)
1296{
1297 struct r1conf *conf = mddev->private;
1298 struct r1bio *r1_bio;
1299
1300 r1_bio = mempool_alloc(&conf->r1bio_pool, GFP_NOIO);
1301 /* Ensure no bio records IO_BLOCKED */
1302 memset(r1_bio->bios, 0, conf->raid_disks * sizeof(r1_bio->bios[0]));
1303 init_r1bio(r1_bio, mddev, bio);
1304 return r1_bio;
1305}
1306
1307static void raid1_read_request(struct mddev *mddev, struct bio *bio,
1308 int max_read_sectors, struct r1bio *r1_bio)
1309{
1310 struct r1conf *conf = mddev->private;
1311 struct raid1_info *mirror;
1312 struct bio *read_bio;
1313 struct bitmap *bitmap = mddev->bitmap;
1314 const enum req_op op = bio_op(bio);
1315 const blk_opf_t do_sync = bio->bi_opf & REQ_SYNC;
1316 int max_sectors;
1317 int rdisk;
1318 bool r1bio_existed = !!r1_bio;
1319 char b[BDEVNAME_SIZE];
1320
1321 /*
1322 * If r1_bio is set, we are blocking the raid1d thread
1323 * so there is a tiny risk of deadlock. So ask for
1324 * emergency memory if needed.
1325 */
1326 gfp_t gfp = r1_bio ? (GFP_NOIO | __GFP_HIGH) : GFP_NOIO;
1327
1328 if (r1bio_existed) {
1329 /* Need to get the block device name carefully */
1330 struct md_rdev *rdev = conf->mirrors[r1_bio->read_disk].rdev;
1331
1332 if (rdev)
1333 snprintf(b, sizeof(b), "%pg", rdev->bdev);
1334 else
1335 strcpy(b, "???");
1336 }
1337
1338 /*
1339 * Still need barrier for READ in case that whole
1340 * array is frozen.
1341 */
1342 if (!wait_read_barrier(conf, bio->bi_iter.bi_sector,
1343 bio->bi_opf & REQ_NOWAIT)) {
1344 bio_wouldblock_error(bio);
1345 return;
1346 }
1347
1348 if (!r1_bio)
1349 r1_bio = alloc_r1bio(mddev, bio);
1350 else
1351 init_r1bio(r1_bio, mddev, bio);
1352 r1_bio->sectors = max_read_sectors;
1353
1354 /*
1355 * make_request() can abort the operation when read-ahead is being
1356 * used and no empty request is available.
1357 */
1358 rdisk = read_balance(conf, r1_bio, &max_sectors);
1359
1360 if (rdisk < 0) {
1361 /* couldn't find anywhere to read from */
1362 if (r1bio_existed) {
1363 pr_crit_ratelimited("md/raid1:%s: %s: unrecoverable I/O read error for block %llu\n",
1364 mdname(mddev),
1365 b,
1366 (unsigned long long)r1_bio->sector);
1367 }
1368 raid_end_bio_io(r1_bio);
1369 return;
1370 }
1371 mirror = conf->mirrors + rdisk;
1372
1373 if (r1bio_existed)
1374 pr_info_ratelimited("md/raid1:%s: redirecting sector %llu to other mirror: %pg\n",
1375 mdname(mddev),
1376 (unsigned long long)r1_bio->sector,
1377 mirror->rdev->bdev);
1378
1379 if (test_bit(WriteMostly, &mirror->rdev->flags) &&
1380 bitmap) {
1381 /*
1382 * Reading from a write-mostly device must take care not to
1383 * over-take any writes that are 'behind'
1384 */
1385 mddev_add_trace_msg(mddev, "raid1 wait behind writes");
1386 wait_event(bitmap->behind_wait,
1387 atomic_read(&bitmap->behind_writes) == 0);
1388 }
1389
1390 if (max_sectors < bio_sectors(bio)) {
1391 struct bio *split = bio_split(bio, max_sectors,
1392 gfp, &conf->bio_split);
1393 bio_chain(split, bio);
1394 submit_bio_noacct(bio);
1395 bio = split;
1396 r1_bio->master_bio = bio;
1397 r1_bio->sectors = max_sectors;
1398 }
1399
1400 r1_bio->read_disk = rdisk;
1401 if (!r1bio_existed) {
1402 md_account_bio(mddev, &bio);
1403 r1_bio->master_bio = bio;
1404 }
1405 read_bio = bio_alloc_clone(mirror->rdev->bdev, bio, gfp,
1406 &mddev->bio_set);
1407
1408 r1_bio->bios[rdisk] = read_bio;
1409
1410 read_bio->bi_iter.bi_sector = r1_bio->sector +
1411 mirror->rdev->data_offset;
1412 read_bio->bi_end_io = raid1_end_read_request;
1413 read_bio->bi_opf = op | do_sync;
1414 if (test_bit(FailFast, &mirror->rdev->flags) &&
1415 test_bit(R1BIO_FailFast, &r1_bio->state))
1416 read_bio->bi_opf |= MD_FAILFAST;
1417 read_bio->bi_private = r1_bio;
1418 mddev_trace_remap(mddev, read_bio, r1_bio->sector);
1419 submit_bio_noacct(read_bio);
1420}
1421
1422static void raid1_write_request(struct mddev *mddev, struct bio *bio,
1423 int max_write_sectors)
1424{
1425 struct r1conf *conf = mddev->private;
1426 struct r1bio *r1_bio;
1427 int i, disks;
1428 struct bitmap *bitmap = mddev->bitmap;
1429 unsigned long flags;
1430 struct md_rdev *blocked_rdev;
1431 int first_clone;
1432 int max_sectors;
1433 bool write_behind = false;
1434 bool is_discard = (bio_op(bio) == REQ_OP_DISCARD);
1435
1436 if (mddev_is_clustered(mddev) &&
1437 md_cluster_ops->area_resyncing(mddev, WRITE,
1438 bio->bi_iter.bi_sector, bio_end_sector(bio))) {
1439
1440 DEFINE_WAIT(w);
1441 if (bio->bi_opf & REQ_NOWAIT) {
1442 bio_wouldblock_error(bio);
1443 return;
1444 }
1445 for (;;) {
1446 prepare_to_wait(&conf->wait_barrier,
1447 &w, TASK_IDLE);
1448 if (!md_cluster_ops->area_resyncing(mddev, WRITE,
1449 bio->bi_iter.bi_sector,
1450 bio_end_sector(bio)))
1451 break;
1452 schedule();
1453 }
1454 finish_wait(&conf->wait_barrier, &w);
1455 }
1456
1457 /*
1458 * Register the new request and wait if the reconstruction
1459 * thread has put up a bar for new requests.
1460 * Continue immediately if no resync is active currently.
1461 */
1462 if (!wait_barrier(conf, bio->bi_iter.bi_sector,
1463 bio->bi_opf & REQ_NOWAIT)) {
1464 bio_wouldblock_error(bio);
1465 return;
1466 }
1467
1468 retry_write:
1469 r1_bio = alloc_r1bio(mddev, bio);
1470 r1_bio->sectors = max_write_sectors;
1471
1472 /* first select target devices under rcu_lock and
1473 * inc refcount on their rdev. Record them by setting
1474 * bios[x] to bio
1475 * If there are known/acknowledged bad blocks on any device on
1476 * which we have seen a write error, we want to avoid writing those
1477 * blocks.
1478 * This potentially requires several writes to write around
1479 * the bad blocks. Each set of writes gets it's own r1bio
1480 * with a set of bios attached.
1481 */
1482
1483 disks = conf->raid_disks * 2;
1484 blocked_rdev = NULL;
1485 max_sectors = r1_bio->sectors;
1486 for (i = 0; i < disks; i++) {
1487 struct md_rdev *rdev = conf->mirrors[i].rdev;
1488
1489 /*
1490 * The write-behind io is only attempted on drives marked as
1491 * write-mostly, which means we could allocate write behind
1492 * bio later.
1493 */
1494 if (!is_discard && rdev && test_bit(WriteMostly, &rdev->flags))
1495 write_behind = true;
1496
1497 if (rdev && unlikely(test_bit(Blocked, &rdev->flags))) {
1498 atomic_inc(&rdev->nr_pending);
1499 blocked_rdev = rdev;
1500 break;
1501 }
1502 r1_bio->bios[i] = NULL;
1503 if (!rdev || test_bit(Faulty, &rdev->flags)) {
1504 if (i < conf->raid_disks)
1505 set_bit(R1BIO_Degraded, &r1_bio->state);
1506 continue;
1507 }
1508
1509 atomic_inc(&rdev->nr_pending);
1510 if (test_bit(WriteErrorSeen, &rdev->flags)) {
1511 sector_t first_bad;
1512 int bad_sectors;
1513 int is_bad;
1514
1515 is_bad = is_badblock(rdev, r1_bio->sector, max_sectors,
1516 &first_bad, &bad_sectors);
1517 if (is_bad < 0) {
1518 /* mustn't write here until the bad block is
1519 * acknowledged*/
1520 set_bit(BlockedBadBlocks, &rdev->flags);
1521 blocked_rdev = rdev;
1522 break;
1523 }
1524 if (is_bad && first_bad <= r1_bio->sector) {
1525 /* Cannot write here at all */
1526 bad_sectors -= (r1_bio->sector - first_bad);
1527 if (bad_sectors < max_sectors)
1528 /* mustn't write more than bad_sectors
1529 * to other devices yet
1530 */
1531 max_sectors = bad_sectors;
1532 rdev_dec_pending(rdev, mddev);
1533 /* We don't set R1BIO_Degraded as that
1534 * only applies if the disk is
1535 * missing, so it might be re-added,
1536 * and we want to know to recover this
1537 * chunk.
1538 * In this case the device is here,
1539 * and the fact that this chunk is not
1540 * in-sync is recorded in the bad
1541 * block log
1542 */
1543 continue;
1544 }
1545 if (is_bad) {
1546 int good_sectors = first_bad - r1_bio->sector;
1547 if (good_sectors < max_sectors)
1548 max_sectors = good_sectors;
1549 }
1550 }
1551 r1_bio->bios[i] = bio;
1552 }
1553
1554 if (unlikely(blocked_rdev)) {
1555 /* Wait for this device to become unblocked */
1556 int j;
1557
1558 for (j = 0; j < i; j++)
1559 if (r1_bio->bios[j])
1560 rdev_dec_pending(conf->mirrors[j].rdev, mddev);
1561 mempool_free(r1_bio, &conf->r1bio_pool);
1562 allow_barrier(conf, bio->bi_iter.bi_sector);
1563
1564 if (bio->bi_opf & REQ_NOWAIT) {
1565 bio_wouldblock_error(bio);
1566 return;
1567 }
1568 mddev_add_trace_msg(mddev, "raid1 wait rdev %d blocked",
1569 blocked_rdev->raid_disk);
1570 md_wait_for_blocked_rdev(blocked_rdev, mddev);
1571 wait_barrier(conf, bio->bi_iter.bi_sector, false);
1572 goto retry_write;
1573 }
1574
1575 /*
1576 * When using a bitmap, we may call alloc_behind_master_bio below.
1577 * alloc_behind_master_bio allocates a copy of the data payload a page
1578 * at a time and thus needs a new bio that can fit the whole payload
1579 * this bio in page sized chunks.
1580 */
1581 if (write_behind && bitmap)
1582 max_sectors = min_t(int, max_sectors,
1583 BIO_MAX_VECS * (PAGE_SIZE >> 9));
1584 if (max_sectors < bio_sectors(bio)) {
1585 struct bio *split = bio_split(bio, max_sectors,
1586 GFP_NOIO, &conf->bio_split);
1587 bio_chain(split, bio);
1588 submit_bio_noacct(bio);
1589 bio = split;
1590 r1_bio->master_bio = bio;
1591 r1_bio->sectors = max_sectors;
1592 }
1593
1594 md_account_bio(mddev, &bio);
1595 r1_bio->master_bio = bio;
1596 atomic_set(&r1_bio->remaining, 1);
1597 atomic_set(&r1_bio->behind_remaining, 0);
1598
1599 first_clone = 1;
1600
1601 for (i = 0; i < disks; i++) {
1602 struct bio *mbio = NULL;
1603 struct md_rdev *rdev = conf->mirrors[i].rdev;
1604 if (!r1_bio->bios[i])
1605 continue;
1606
1607 if (first_clone) {
1608 /* do behind I/O ?
1609 * Not if there are too many, or cannot
1610 * allocate memory, or a reader on WriteMostly
1611 * is waiting for behind writes to flush */
1612 if (bitmap && write_behind &&
1613 (atomic_read(&bitmap->behind_writes)
1614 < mddev->bitmap_info.max_write_behind) &&
1615 !waitqueue_active(&bitmap->behind_wait)) {
1616 alloc_behind_master_bio(r1_bio, bio);
1617 }
1618
1619 md_bitmap_startwrite(bitmap, r1_bio->sector, r1_bio->sectors,
1620 test_bit(R1BIO_BehindIO, &r1_bio->state));
1621 first_clone = 0;
1622 }
1623
1624 if (r1_bio->behind_master_bio) {
1625 mbio = bio_alloc_clone(rdev->bdev,
1626 r1_bio->behind_master_bio,
1627 GFP_NOIO, &mddev->bio_set);
1628 if (test_bit(CollisionCheck, &rdev->flags))
1629 wait_for_serialization(rdev, r1_bio);
1630 if (test_bit(WriteMostly, &rdev->flags))
1631 atomic_inc(&r1_bio->behind_remaining);
1632 } else {
1633 mbio = bio_alloc_clone(rdev->bdev, bio, GFP_NOIO,
1634 &mddev->bio_set);
1635
1636 if (mddev->serialize_policy)
1637 wait_for_serialization(rdev, r1_bio);
1638 }
1639
1640 r1_bio->bios[i] = mbio;
1641
1642 mbio->bi_iter.bi_sector = (r1_bio->sector + rdev->data_offset);
1643 mbio->bi_end_io = raid1_end_write_request;
1644 mbio->bi_opf = bio_op(bio) | (bio->bi_opf & (REQ_SYNC | REQ_FUA));
1645 if (test_bit(FailFast, &rdev->flags) &&
1646 !test_bit(WriteMostly, &rdev->flags) &&
1647 conf->raid_disks - mddev->degraded > 1)
1648 mbio->bi_opf |= MD_FAILFAST;
1649 mbio->bi_private = r1_bio;
1650
1651 atomic_inc(&r1_bio->remaining);
1652 mddev_trace_remap(mddev, mbio, r1_bio->sector);
1653 /* flush_pending_writes() needs access to the rdev so...*/
1654 mbio->bi_bdev = (void *)rdev;
1655 if (!raid1_add_bio_to_plug(mddev, mbio, raid1_unplug, disks)) {
1656 spin_lock_irqsave(&conf->device_lock, flags);
1657 bio_list_add(&conf->pending_bio_list, mbio);
1658 spin_unlock_irqrestore(&conf->device_lock, flags);
1659 md_wakeup_thread(mddev->thread);
1660 }
1661 }
1662
1663 r1_bio_write_done(r1_bio);
1664
1665 /* In case raid1d snuck in to freeze_array */
1666 wake_up_barrier(conf);
1667}
1668
1669static bool raid1_make_request(struct mddev *mddev, struct bio *bio)
1670{
1671 sector_t sectors;
1672
1673 if (unlikely(bio->bi_opf & REQ_PREFLUSH)
1674 && md_flush_request(mddev, bio))
1675 return true;
1676
1677 /*
1678 * There is a limit to the maximum size, but
1679 * the read/write handler might find a lower limit
1680 * due to bad blocks. To avoid multiple splits,
1681 * we pass the maximum number of sectors down
1682 * and let the lower level perform the split.
1683 */
1684 sectors = align_to_barrier_unit_end(
1685 bio->bi_iter.bi_sector, bio_sectors(bio));
1686
1687 if (bio_data_dir(bio) == READ)
1688 raid1_read_request(mddev, bio, sectors, NULL);
1689 else {
1690 if (!md_write_start(mddev,bio))
1691 return false;
1692 raid1_write_request(mddev, bio, sectors);
1693 }
1694 return true;
1695}
1696
1697static void raid1_status(struct seq_file *seq, struct mddev *mddev)
1698{
1699 struct r1conf *conf = mddev->private;
1700 int i;
1701
1702 lockdep_assert_held(&mddev->lock);
1703
1704 seq_printf(seq, " [%d/%d] [", conf->raid_disks,
1705 conf->raid_disks - mddev->degraded);
1706 for (i = 0; i < conf->raid_disks; i++) {
1707 struct md_rdev *rdev = READ_ONCE(conf->mirrors[i].rdev);
1708
1709 seq_printf(seq, "%s",
1710 rdev && test_bit(In_sync, &rdev->flags) ? "U" : "_");
1711 }
1712 seq_printf(seq, "]");
1713}
1714
1715/**
1716 * raid1_error() - RAID1 error handler.
1717 * @mddev: affected md device.
1718 * @rdev: member device to fail.
1719 *
1720 * The routine acknowledges &rdev failure and determines new @mddev state.
1721 * If it failed, then:
1722 * - &MD_BROKEN flag is set in &mddev->flags.
1723 * - recovery is disabled.
1724 * Otherwise, it must be degraded:
1725 * - recovery is interrupted.
1726 * - &mddev->degraded is bumped.
1727 *
1728 * @rdev is marked as &Faulty excluding case when array is failed and
1729 * &mddev->fail_last_dev is off.
1730 */
1731static void raid1_error(struct mddev *mddev, struct md_rdev *rdev)
1732{
1733 struct r1conf *conf = mddev->private;
1734 unsigned long flags;
1735
1736 spin_lock_irqsave(&conf->device_lock, flags);
1737
1738 if (test_bit(In_sync, &rdev->flags) &&
1739 (conf->raid_disks - mddev->degraded) == 1) {
1740 set_bit(MD_BROKEN, &mddev->flags);
1741
1742 if (!mddev->fail_last_dev) {
1743 conf->recovery_disabled = mddev->recovery_disabled;
1744 spin_unlock_irqrestore(&conf->device_lock, flags);
1745 return;
1746 }
1747 }
1748 set_bit(Blocked, &rdev->flags);
1749 if (test_and_clear_bit(In_sync, &rdev->flags))
1750 mddev->degraded++;
1751 set_bit(Faulty, &rdev->flags);
1752 spin_unlock_irqrestore(&conf->device_lock, flags);
1753 /*
1754 * if recovery is running, make sure it aborts.
1755 */
1756 set_bit(MD_RECOVERY_INTR, &mddev->recovery);
1757 set_mask_bits(&mddev->sb_flags, 0,
1758 BIT(MD_SB_CHANGE_DEVS) | BIT(MD_SB_CHANGE_PENDING));
1759 pr_crit("md/raid1:%s: Disk failure on %pg, disabling device.\n"
1760 "md/raid1:%s: Operation continuing on %d devices.\n",
1761 mdname(mddev), rdev->bdev,
1762 mdname(mddev), conf->raid_disks - mddev->degraded);
1763}
1764
1765static void print_conf(struct r1conf *conf)
1766{
1767 int i;
1768
1769 pr_debug("RAID1 conf printout:\n");
1770 if (!conf) {
1771 pr_debug("(!conf)\n");
1772 return;
1773 }
1774 pr_debug(" --- wd:%d rd:%d\n", conf->raid_disks - conf->mddev->degraded,
1775 conf->raid_disks);
1776
1777 lockdep_assert_held(&conf->mddev->reconfig_mutex);
1778 for (i = 0; i < conf->raid_disks; i++) {
1779 struct md_rdev *rdev = conf->mirrors[i].rdev;
1780 if (rdev)
1781 pr_debug(" disk %d, wo:%d, o:%d, dev:%pg\n",
1782 i, !test_bit(In_sync, &rdev->flags),
1783 !test_bit(Faulty, &rdev->flags),
1784 rdev->bdev);
1785 }
1786}
1787
1788static void close_sync(struct r1conf *conf)
1789{
1790 int idx;
1791
1792 for (idx = 0; idx < BARRIER_BUCKETS_NR; idx++) {
1793 _wait_barrier(conf, idx, false);
1794 _allow_barrier(conf, idx);
1795 }
1796
1797 mempool_exit(&conf->r1buf_pool);
1798}
1799
1800static int raid1_spare_active(struct mddev *mddev)
1801{
1802 int i;
1803 struct r1conf *conf = mddev->private;
1804 int count = 0;
1805 unsigned long flags;
1806
1807 /*
1808 * Find all failed disks within the RAID1 configuration
1809 * and mark them readable.
1810 * Called under mddev lock, so rcu protection not needed.
1811 * device_lock used to avoid races with raid1_end_read_request
1812 * which expects 'In_sync' flags and ->degraded to be consistent.
1813 */
1814 spin_lock_irqsave(&conf->device_lock, flags);
1815 for (i = 0; i < conf->raid_disks; i++) {
1816 struct md_rdev *rdev = conf->mirrors[i].rdev;
1817 struct md_rdev *repl = conf->mirrors[conf->raid_disks + i].rdev;
1818 if (repl
1819 && !test_bit(Candidate, &repl->flags)
1820 && repl->recovery_offset == MaxSector
1821 && !test_bit(Faulty, &repl->flags)
1822 && !test_and_set_bit(In_sync, &repl->flags)) {
1823 /* replacement has just become active */
1824 if (!rdev ||
1825 !test_and_clear_bit(In_sync, &rdev->flags))
1826 count++;
1827 if (rdev) {
1828 /* Replaced device not technically
1829 * faulty, but we need to be sure
1830 * it gets removed and never re-added
1831 */
1832 set_bit(Faulty, &rdev->flags);
1833 sysfs_notify_dirent_safe(
1834 rdev->sysfs_state);
1835 }
1836 }
1837 if (rdev
1838 && rdev->recovery_offset == MaxSector
1839 && !test_bit(Faulty, &rdev->flags)
1840 && !test_and_set_bit(In_sync, &rdev->flags)) {
1841 count++;
1842 sysfs_notify_dirent_safe(rdev->sysfs_state);
1843 }
1844 }
1845 mddev->degraded -= count;
1846 spin_unlock_irqrestore(&conf->device_lock, flags);
1847
1848 print_conf(conf);
1849 return count;
1850}
1851
1852static bool raid1_add_conf(struct r1conf *conf, struct md_rdev *rdev, int disk,
1853 bool replacement)
1854{
1855 struct raid1_info *info = conf->mirrors + disk;
1856
1857 if (replacement)
1858 info += conf->raid_disks;
1859
1860 if (info->rdev)
1861 return false;
1862
1863 if (bdev_nonrot(rdev->bdev)) {
1864 set_bit(Nonrot, &rdev->flags);
1865 WRITE_ONCE(conf->nonrot_disks, conf->nonrot_disks + 1);
1866 }
1867
1868 rdev->raid_disk = disk;
1869 info->head_position = 0;
1870 info->seq_start = MaxSector;
1871 WRITE_ONCE(info->rdev, rdev);
1872
1873 return true;
1874}
1875
1876static bool raid1_remove_conf(struct r1conf *conf, int disk)
1877{
1878 struct raid1_info *info = conf->mirrors + disk;
1879 struct md_rdev *rdev = info->rdev;
1880
1881 if (!rdev || test_bit(In_sync, &rdev->flags) ||
1882 atomic_read(&rdev->nr_pending))
1883 return false;
1884
1885 /* Only remove non-faulty devices if recovery is not possible. */
1886 if (!test_bit(Faulty, &rdev->flags) &&
1887 rdev->mddev->recovery_disabled != conf->recovery_disabled &&
1888 rdev->mddev->degraded < conf->raid_disks)
1889 return false;
1890
1891 if (test_and_clear_bit(Nonrot, &rdev->flags))
1892 WRITE_ONCE(conf->nonrot_disks, conf->nonrot_disks - 1);
1893
1894 WRITE_ONCE(info->rdev, NULL);
1895 return true;
1896}
1897
1898static int raid1_add_disk(struct mddev *mddev, struct md_rdev *rdev)
1899{
1900 struct r1conf *conf = mddev->private;
1901 int err = -EEXIST;
1902 int mirror = 0, repl_slot = -1;
1903 struct raid1_info *p;
1904 int first = 0;
1905 int last = conf->raid_disks - 1;
1906
1907 if (mddev->recovery_disabled == conf->recovery_disabled)
1908 return -EBUSY;
1909
1910 if (md_integrity_add_rdev(rdev, mddev))
1911 return -ENXIO;
1912
1913 if (rdev->raid_disk >= 0)
1914 first = last = rdev->raid_disk;
1915
1916 /*
1917 * find the disk ... but prefer rdev->saved_raid_disk
1918 * if possible.
1919 */
1920 if (rdev->saved_raid_disk >= 0 &&
1921 rdev->saved_raid_disk >= first &&
1922 rdev->saved_raid_disk < conf->raid_disks &&
1923 conf->mirrors[rdev->saved_raid_disk].rdev == NULL)
1924 first = last = rdev->saved_raid_disk;
1925
1926 for (mirror = first; mirror <= last; mirror++) {
1927 p = conf->mirrors + mirror;
1928 if (!p->rdev) {
1929 err = mddev_stack_new_rdev(mddev, rdev);
1930 if (err)
1931 return err;
1932
1933 raid1_add_conf(conf, rdev, mirror, false);
1934 /* As all devices are equivalent, we don't need a full recovery
1935 * if this was recently any drive of the array
1936 */
1937 if (rdev->saved_raid_disk < 0)
1938 conf->fullsync = 1;
1939 break;
1940 }
1941 if (test_bit(WantReplacement, &p->rdev->flags) &&
1942 p[conf->raid_disks].rdev == NULL && repl_slot < 0)
1943 repl_slot = mirror;
1944 }
1945
1946 if (err && repl_slot >= 0) {
1947 /* Add this device as a replacement */
1948 clear_bit(In_sync, &rdev->flags);
1949 set_bit(Replacement, &rdev->flags);
1950 raid1_add_conf(conf, rdev, repl_slot, true);
1951 err = 0;
1952 conf->fullsync = 1;
1953 }
1954
1955 print_conf(conf);
1956 return err;
1957}
1958
1959static int raid1_remove_disk(struct mddev *mddev, struct md_rdev *rdev)
1960{
1961 struct r1conf *conf = mddev->private;
1962 int err = 0;
1963 int number = rdev->raid_disk;
1964 struct raid1_info *p = conf->mirrors + number;
1965
1966 if (unlikely(number >= conf->raid_disks))
1967 goto abort;
1968
1969 if (rdev != p->rdev) {
1970 number += conf->raid_disks;
1971 p = conf->mirrors + number;
1972 }
1973
1974 print_conf(conf);
1975 if (rdev == p->rdev) {
1976 if (!raid1_remove_conf(conf, number)) {
1977 err = -EBUSY;
1978 goto abort;
1979 }
1980
1981 if (number < conf->raid_disks &&
1982 conf->mirrors[conf->raid_disks + number].rdev) {
1983 /* We just removed a device that is being replaced.
1984 * Move down the replacement. We drain all IO before
1985 * doing this to avoid confusion.
1986 */
1987 struct md_rdev *repl =
1988 conf->mirrors[conf->raid_disks + number].rdev;
1989 freeze_array(conf, 0);
1990 if (atomic_read(&repl->nr_pending)) {
1991 /* It means that some queued IO of retry_list
1992 * hold repl. Thus, we cannot set replacement
1993 * as NULL, avoiding rdev NULL pointer
1994 * dereference in sync_request_write and
1995 * handle_write_finished.
1996 */
1997 err = -EBUSY;
1998 unfreeze_array(conf);
1999 goto abort;
2000 }
2001 clear_bit(Replacement, &repl->flags);
2002 WRITE_ONCE(p->rdev, repl);
2003 conf->mirrors[conf->raid_disks + number].rdev = NULL;
2004 unfreeze_array(conf);
2005 }
2006
2007 clear_bit(WantReplacement, &rdev->flags);
2008 err = md_integrity_register(mddev);
2009 }
2010abort:
2011
2012 print_conf(conf);
2013 return err;
2014}
2015
2016static void end_sync_read(struct bio *bio)
2017{
2018 struct r1bio *r1_bio = get_resync_r1bio(bio);
2019
2020 update_head_pos(r1_bio->read_disk, r1_bio);
2021
2022 /*
2023 * we have read a block, now it needs to be re-written,
2024 * or re-read if the read failed.
2025 * We don't do much here, just schedule handling by raid1d
2026 */
2027 if (!bio->bi_status)
2028 set_bit(R1BIO_Uptodate, &r1_bio->state);
2029
2030 if (atomic_dec_and_test(&r1_bio->remaining))
2031 reschedule_retry(r1_bio);
2032}
2033
2034static void abort_sync_write(struct mddev *mddev, struct r1bio *r1_bio)
2035{
2036 sector_t sync_blocks = 0;
2037 sector_t s = r1_bio->sector;
2038 long sectors_to_go = r1_bio->sectors;
2039
2040 /* make sure these bits don't get cleared. */
2041 do {
2042 md_bitmap_end_sync(mddev->bitmap, s, &sync_blocks, 1);
2043 s += sync_blocks;
2044 sectors_to_go -= sync_blocks;
2045 } while (sectors_to_go > 0);
2046}
2047
2048static void put_sync_write_buf(struct r1bio *r1_bio, int uptodate)
2049{
2050 if (atomic_dec_and_test(&r1_bio->remaining)) {
2051 struct mddev *mddev = r1_bio->mddev;
2052 int s = r1_bio->sectors;
2053
2054 if (test_bit(R1BIO_MadeGood, &r1_bio->state) ||
2055 test_bit(R1BIO_WriteError, &r1_bio->state))
2056 reschedule_retry(r1_bio);
2057 else {
2058 put_buf(r1_bio);
2059 md_done_sync(mddev, s, uptodate);
2060 }
2061 }
2062}
2063
2064static void end_sync_write(struct bio *bio)
2065{
2066 int uptodate = !bio->bi_status;
2067 struct r1bio *r1_bio = get_resync_r1bio(bio);
2068 struct mddev *mddev = r1_bio->mddev;
2069 struct r1conf *conf = mddev->private;
2070 struct md_rdev *rdev = conf->mirrors[find_bio_disk(r1_bio, bio)].rdev;
2071
2072 if (!uptodate) {
2073 abort_sync_write(mddev, r1_bio);
2074 set_bit(WriteErrorSeen, &rdev->flags);
2075 if (!test_and_set_bit(WantReplacement, &rdev->flags))
2076 set_bit(MD_RECOVERY_NEEDED, &
2077 mddev->recovery);
2078 set_bit(R1BIO_WriteError, &r1_bio->state);
2079 } else if (rdev_has_badblock(rdev, r1_bio->sector, r1_bio->sectors) &&
2080 !rdev_has_badblock(conf->mirrors[r1_bio->read_disk].rdev,
2081 r1_bio->sector, r1_bio->sectors)) {
2082 set_bit(R1BIO_MadeGood, &r1_bio->state);
2083 }
2084
2085 put_sync_write_buf(r1_bio, uptodate);
2086}
2087
2088static int r1_sync_page_io(struct md_rdev *rdev, sector_t sector,
2089 int sectors, struct page *page, blk_opf_t rw)
2090{
2091 if (sync_page_io(rdev, sector, sectors << 9, page, rw, false))
2092 /* success */
2093 return 1;
2094 if (rw == REQ_OP_WRITE) {
2095 set_bit(WriteErrorSeen, &rdev->flags);
2096 if (!test_and_set_bit(WantReplacement,
2097 &rdev->flags))
2098 set_bit(MD_RECOVERY_NEEDED, &
2099 rdev->mddev->recovery);
2100 }
2101 /* need to record an error - either for the block or the device */
2102 if (!rdev_set_badblocks(rdev, sector, sectors, 0))
2103 md_error(rdev->mddev, rdev);
2104 return 0;
2105}
2106
2107static int fix_sync_read_error(struct r1bio *r1_bio)
2108{
2109 /* Try some synchronous reads of other devices to get
2110 * good data, much like with normal read errors. Only
2111 * read into the pages we already have so we don't
2112 * need to re-issue the read request.
2113 * We don't need to freeze the array, because being in an
2114 * active sync request, there is no normal IO, and
2115 * no overlapping syncs.
2116 * We don't need to check is_badblock() again as we
2117 * made sure that anything with a bad block in range
2118 * will have bi_end_io clear.
2119 */
2120 struct mddev *mddev = r1_bio->mddev;
2121 struct r1conf *conf = mddev->private;
2122 struct bio *bio = r1_bio->bios[r1_bio->read_disk];
2123 struct page **pages = get_resync_pages(bio)->pages;
2124 sector_t sect = r1_bio->sector;
2125 int sectors = r1_bio->sectors;
2126 int idx = 0;
2127 struct md_rdev *rdev;
2128
2129 rdev = conf->mirrors[r1_bio->read_disk].rdev;
2130 if (test_bit(FailFast, &rdev->flags)) {
2131 /* Don't try recovering from here - just fail it
2132 * ... unless it is the last working device of course */
2133 md_error(mddev, rdev);
2134 if (test_bit(Faulty, &rdev->flags))
2135 /* Don't try to read from here, but make sure
2136 * put_buf does it's thing
2137 */
2138 bio->bi_end_io = end_sync_write;
2139 }
2140
2141 while(sectors) {
2142 int s = sectors;
2143 int d = r1_bio->read_disk;
2144 int success = 0;
2145 int start;
2146
2147 if (s > (PAGE_SIZE>>9))
2148 s = PAGE_SIZE >> 9;
2149 do {
2150 if (r1_bio->bios[d]->bi_end_io == end_sync_read) {
2151 /* No rcu protection needed here devices
2152 * can only be removed when no resync is
2153 * active, and resync is currently active
2154 */
2155 rdev = conf->mirrors[d].rdev;
2156 if (sync_page_io(rdev, sect, s<<9,
2157 pages[idx],
2158 REQ_OP_READ, false)) {
2159 success = 1;
2160 break;
2161 }
2162 }
2163 d++;
2164 if (d == conf->raid_disks * 2)
2165 d = 0;
2166 } while (!success && d != r1_bio->read_disk);
2167
2168 if (!success) {
2169 int abort = 0;
2170 /* Cannot read from anywhere, this block is lost.
2171 * Record a bad block on each device. If that doesn't
2172 * work just disable and interrupt the recovery.
2173 * Don't fail devices as that won't really help.
2174 */
2175 pr_crit_ratelimited("md/raid1:%s: %pg: unrecoverable I/O read error for block %llu\n",
2176 mdname(mddev), bio->bi_bdev,
2177 (unsigned long long)r1_bio->sector);
2178 for (d = 0; d < conf->raid_disks * 2; d++) {
2179 rdev = conf->mirrors[d].rdev;
2180 if (!rdev || test_bit(Faulty, &rdev->flags))
2181 continue;
2182 if (!rdev_set_badblocks(rdev, sect, s, 0))
2183 abort = 1;
2184 }
2185 if (abort) {
2186 conf->recovery_disabled =
2187 mddev->recovery_disabled;
2188 set_bit(MD_RECOVERY_INTR, &mddev->recovery);
2189 md_done_sync(mddev, r1_bio->sectors, 0);
2190 put_buf(r1_bio);
2191 return 0;
2192 }
2193 /* Try next page */
2194 sectors -= s;
2195 sect += s;
2196 idx++;
2197 continue;
2198 }
2199
2200 start = d;
2201 /* write it back and re-read */
2202 while (d != r1_bio->read_disk) {
2203 if (d == 0)
2204 d = conf->raid_disks * 2;
2205 d--;
2206 if (r1_bio->bios[d]->bi_end_io != end_sync_read)
2207 continue;
2208 rdev = conf->mirrors[d].rdev;
2209 if (r1_sync_page_io(rdev, sect, s,
2210 pages[idx],
2211 REQ_OP_WRITE) == 0) {
2212 r1_bio->bios[d]->bi_end_io = NULL;
2213 rdev_dec_pending(rdev, mddev);
2214 }
2215 }
2216 d = start;
2217 while (d != r1_bio->read_disk) {
2218 if (d == 0)
2219 d = conf->raid_disks * 2;
2220 d--;
2221 if (r1_bio->bios[d]->bi_end_io != end_sync_read)
2222 continue;
2223 rdev = conf->mirrors[d].rdev;
2224 if (r1_sync_page_io(rdev, sect, s,
2225 pages[idx],
2226 REQ_OP_READ) != 0)
2227 atomic_add(s, &rdev->corrected_errors);
2228 }
2229 sectors -= s;
2230 sect += s;
2231 idx ++;
2232 }
2233 set_bit(R1BIO_Uptodate, &r1_bio->state);
2234 bio->bi_status = 0;
2235 return 1;
2236}
2237
2238static void process_checks(struct r1bio *r1_bio)
2239{
2240 /* We have read all readable devices. If we haven't
2241 * got the block, then there is no hope left.
2242 * If we have, then we want to do a comparison
2243 * and skip the write if everything is the same.
2244 * If any blocks failed to read, then we need to
2245 * attempt an over-write
2246 */
2247 struct mddev *mddev = r1_bio->mddev;
2248 struct r1conf *conf = mddev->private;
2249 int primary;
2250 int i;
2251 int vcnt;
2252
2253 /* Fix variable parts of all bios */
2254 vcnt = (r1_bio->sectors + PAGE_SIZE / 512 - 1) >> (PAGE_SHIFT - 9);
2255 for (i = 0; i < conf->raid_disks * 2; i++) {
2256 blk_status_t status;
2257 struct bio *b = r1_bio->bios[i];
2258 struct resync_pages *rp = get_resync_pages(b);
2259 if (b->bi_end_io != end_sync_read)
2260 continue;
2261 /* fixup the bio for reuse, but preserve errno */
2262 status = b->bi_status;
2263 bio_reset(b, conf->mirrors[i].rdev->bdev, REQ_OP_READ);
2264 b->bi_status = status;
2265 b->bi_iter.bi_sector = r1_bio->sector +
2266 conf->mirrors[i].rdev->data_offset;
2267 b->bi_end_io = end_sync_read;
2268 rp->raid_bio = r1_bio;
2269 b->bi_private = rp;
2270
2271 /* initialize bvec table again */
2272 md_bio_reset_resync_pages(b, rp, r1_bio->sectors << 9);
2273 }
2274 for (primary = 0; primary < conf->raid_disks * 2; primary++)
2275 if (r1_bio->bios[primary]->bi_end_io == end_sync_read &&
2276 !r1_bio->bios[primary]->bi_status) {
2277 r1_bio->bios[primary]->bi_end_io = NULL;
2278 rdev_dec_pending(conf->mirrors[primary].rdev, mddev);
2279 break;
2280 }
2281 r1_bio->read_disk = primary;
2282 for (i = 0; i < conf->raid_disks * 2; i++) {
2283 int j = 0;
2284 struct bio *pbio = r1_bio->bios[primary];
2285 struct bio *sbio = r1_bio->bios[i];
2286 blk_status_t status = sbio->bi_status;
2287 struct page **ppages = get_resync_pages(pbio)->pages;
2288 struct page **spages = get_resync_pages(sbio)->pages;
2289 struct bio_vec *bi;
2290 int page_len[RESYNC_PAGES] = { 0 };
2291 struct bvec_iter_all iter_all;
2292
2293 if (sbio->bi_end_io != end_sync_read)
2294 continue;
2295 /* Now we can 'fixup' the error value */
2296 sbio->bi_status = 0;
2297
2298 bio_for_each_segment_all(bi, sbio, iter_all)
2299 page_len[j++] = bi->bv_len;
2300
2301 if (!status) {
2302 for (j = vcnt; j-- ; ) {
2303 if (memcmp(page_address(ppages[j]),
2304 page_address(spages[j]),
2305 page_len[j]))
2306 break;
2307 }
2308 } else
2309 j = 0;
2310 if (j >= 0)
2311 atomic64_add(r1_bio->sectors, &mddev->resync_mismatches);
2312 if (j < 0 || (test_bit(MD_RECOVERY_CHECK, &mddev->recovery)
2313 && !status)) {
2314 /* No need to write to this device. */
2315 sbio->bi_end_io = NULL;
2316 rdev_dec_pending(conf->mirrors[i].rdev, mddev);
2317 continue;
2318 }
2319
2320 bio_copy_data(sbio, pbio);
2321 }
2322}
2323
2324static void sync_request_write(struct mddev *mddev, struct r1bio *r1_bio)
2325{
2326 struct r1conf *conf = mddev->private;
2327 int i;
2328 int disks = conf->raid_disks * 2;
2329 struct bio *wbio;
2330
2331 if (!test_bit(R1BIO_Uptodate, &r1_bio->state))
2332 /* ouch - failed to read all of that. */
2333 if (!fix_sync_read_error(r1_bio))
2334 return;
2335
2336 if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
2337 process_checks(r1_bio);
2338
2339 /*
2340 * schedule writes
2341 */
2342 atomic_set(&r1_bio->remaining, 1);
2343 for (i = 0; i < disks ; i++) {
2344 wbio = r1_bio->bios[i];
2345 if (wbio->bi_end_io == NULL ||
2346 (wbio->bi_end_io == end_sync_read &&
2347 (i == r1_bio->read_disk ||
2348 !test_bit(MD_RECOVERY_SYNC, &mddev->recovery))))
2349 continue;
2350 if (test_bit(Faulty, &conf->mirrors[i].rdev->flags)) {
2351 abort_sync_write(mddev, r1_bio);
2352 continue;
2353 }
2354
2355 wbio->bi_opf = REQ_OP_WRITE;
2356 if (test_bit(FailFast, &conf->mirrors[i].rdev->flags))
2357 wbio->bi_opf |= MD_FAILFAST;
2358
2359 wbio->bi_end_io = end_sync_write;
2360 atomic_inc(&r1_bio->remaining);
2361 md_sync_acct(conf->mirrors[i].rdev->bdev, bio_sectors(wbio));
2362
2363 submit_bio_noacct(wbio);
2364 }
2365
2366 put_sync_write_buf(r1_bio, 1);
2367}
2368
2369/*
2370 * This is a kernel thread which:
2371 *
2372 * 1. Retries failed read operations on working mirrors.
2373 * 2. Updates the raid superblock when problems encounter.
2374 * 3. Performs writes following reads for array synchronising.
2375 */
2376
2377static void fix_read_error(struct r1conf *conf, struct r1bio *r1_bio)
2378{
2379 sector_t sect = r1_bio->sector;
2380 int sectors = r1_bio->sectors;
2381 int read_disk = r1_bio->read_disk;
2382 struct mddev *mddev = conf->mddev;
2383 struct md_rdev *rdev = conf->mirrors[read_disk].rdev;
2384
2385 if (exceed_read_errors(mddev, rdev)) {
2386 r1_bio->bios[r1_bio->read_disk] = IO_BLOCKED;
2387 return;
2388 }
2389
2390 while(sectors) {
2391 int s = sectors;
2392 int d = read_disk;
2393 int success = 0;
2394 int start;
2395
2396 if (s > (PAGE_SIZE>>9))
2397 s = PAGE_SIZE >> 9;
2398
2399 do {
2400 rdev = conf->mirrors[d].rdev;
2401 if (rdev &&
2402 (test_bit(In_sync, &rdev->flags) ||
2403 (!test_bit(Faulty, &rdev->flags) &&
2404 rdev->recovery_offset >= sect + s)) &&
2405 rdev_has_badblock(rdev, sect, s) == 0) {
2406 atomic_inc(&rdev->nr_pending);
2407 if (sync_page_io(rdev, sect, s<<9,
2408 conf->tmppage, REQ_OP_READ, false))
2409 success = 1;
2410 rdev_dec_pending(rdev, mddev);
2411 if (success)
2412 break;
2413 }
2414
2415 d++;
2416 if (d == conf->raid_disks * 2)
2417 d = 0;
2418 } while (d != read_disk);
2419
2420 if (!success) {
2421 /* Cannot read from anywhere - mark it bad */
2422 struct md_rdev *rdev = conf->mirrors[read_disk].rdev;
2423 if (!rdev_set_badblocks(rdev, sect, s, 0))
2424 md_error(mddev, rdev);
2425 break;
2426 }
2427 /* write it back and re-read */
2428 start = d;
2429 while (d != read_disk) {
2430 if (d==0)
2431 d = conf->raid_disks * 2;
2432 d--;
2433 rdev = conf->mirrors[d].rdev;
2434 if (rdev &&
2435 !test_bit(Faulty, &rdev->flags)) {
2436 atomic_inc(&rdev->nr_pending);
2437 r1_sync_page_io(rdev, sect, s,
2438 conf->tmppage, REQ_OP_WRITE);
2439 rdev_dec_pending(rdev, mddev);
2440 }
2441 }
2442 d = start;
2443 while (d != read_disk) {
2444 if (d==0)
2445 d = conf->raid_disks * 2;
2446 d--;
2447 rdev = conf->mirrors[d].rdev;
2448 if (rdev &&
2449 !test_bit(Faulty, &rdev->flags)) {
2450 atomic_inc(&rdev->nr_pending);
2451 if (r1_sync_page_io(rdev, sect, s,
2452 conf->tmppage, REQ_OP_READ)) {
2453 atomic_add(s, &rdev->corrected_errors);
2454 pr_info("md/raid1:%s: read error corrected (%d sectors at %llu on %pg)\n",
2455 mdname(mddev), s,
2456 (unsigned long long)(sect +
2457 rdev->data_offset),
2458 rdev->bdev);
2459 }
2460 rdev_dec_pending(rdev, mddev);
2461 }
2462 }
2463 sectors -= s;
2464 sect += s;
2465 }
2466}
2467
2468static int narrow_write_error(struct r1bio *r1_bio, int i)
2469{
2470 struct mddev *mddev = r1_bio->mddev;
2471 struct r1conf *conf = mddev->private;
2472 struct md_rdev *rdev = conf->mirrors[i].rdev;
2473
2474 /* bio has the data to be written to device 'i' where
2475 * we just recently had a write error.
2476 * We repeatedly clone the bio and trim down to one block,
2477 * then try the write. Where the write fails we record
2478 * a bad block.
2479 * It is conceivable that the bio doesn't exactly align with
2480 * blocks. We must handle this somehow.
2481 *
2482 * We currently own a reference on the rdev.
2483 */
2484
2485 int block_sectors;
2486 sector_t sector;
2487 int sectors;
2488 int sect_to_write = r1_bio->sectors;
2489 int ok = 1;
2490
2491 if (rdev->badblocks.shift < 0)
2492 return 0;
2493
2494 block_sectors = roundup(1 << rdev->badblocks.shift,
2495 bdev_logical_block_size(rdev->bdev) >> 9);
2496 sector = r1_bio->sector;
2497 sectors = ((sector + block_sectors)
2498 & ~(sector_t)(block_sectors - 1))
2499 - sector;
2500
2501 while (sect_to_write) {
2502 struct bio *wbio;
2503 if (sectors > sect_to_write)
2504 sectors = sect_to_write;
2505 /* Write at 'sector' for 'sectors'*/
2506
2507 if (test_bit(R1BIO_BehindIO, &r1_bio->state)) {
2508 wbio = bio_alloc_clone(rdev->bdev,
2509 r1_bio->behind_master_bio,
2510 GFP_NOIO, &mddev->bio_set);
2511 } else {
2512 wbio = bio_alloc_clone(rdev->bdev, r1_bio->master_bio,
2513 GFP_NOIO, &mddev->bio_set);
2514 }
2515
2516 wbio->bi_opf = REQ_OP_WRITE;
2517 wbio->bi_iter.bi_sector = r1_bio->sector;
2518 wbio->bi_iter.bi_size = r1_bio->sectors << 9;
2519
2520 bio_trim(wbio, sector - r1_bio->sector, sectors);
2521 wbio->bi_iter.bi_sector += rdev->data_offset;
2522
2523 if (submit_bio_wait(wbio) < 0)
2524 /* failure! */
2525 ok = rdev_set_badblocks(rdev, sector,
2526 sectors, 0)
2527 && ok;
2528
2529 bio_put(wbio);
2530 sect_to_write -= sectors;
2531 sector += sectors;
2532 sectors = block_sectors;
2533 }
2534 return ok;
2535}
2536
2537static void handle_sync_write_finished(struct r1conf *conf, struct r1bio *r1_bio)
2538{
2539 int m;
2540 int s = r1_bio->sectors;
2541 for (m = 0; m < conf->raid_disks * 2 ; m++) {
2542 struct md_rdev *rdev = conf->mirrors[m].rdev;
2543 struct bio *bio = r1_bio->bios[m];
2544 if (bio->bi_end_io == NULL)
2545 continue;
2546 if (!bio->bi_status &&
2547 test_bit(R1BIO_MadeGood, &r1_bio->state)) {
2548 rdev_clear_badblocks(rdev, r1_bio->sector, s, 0);
2549 }
2550 if (bio->bi_status &&
2551 test_bit(R1BIO_WriteError, &r1_bio->state)) {
2552 if (!rdev_set_badblocks(rdev, r1_bio->sector, s, 0))
2553 md_error(conf->mddev, rdev);
2554 }
2555 }
2556 put_buf(r1_bio);
2557 md_done_sync(conf->mddev, s, 1);
2558}
2559
2560static void handle_write_finished(struct r1conf *conf, struct r1bio *r1_bio)
2561{
2562 int m, idx;
2563 bool fail = false;
2564
2565 for (m = 0; m < conf->raid_disks * 2 ; m++)
2566 if (r1_bio->bios[m] == IO_MADE_GOOD) {
2567 struct md_rdev *rdev = conf->mirrors[m].rdev;
2568 rdev_clear_badblocks(rdev,
2569 r1_bio->sector,
2570 r1_bio->sectors, 0);
2571 rdev_dec_pending(rdev, conf->mddev);
2572 } else if (r1_bio->bios[m] != NULL) {
2573 /* This drive got a write error. We need to
2574 * narrow down and record precise write
2575 * errors.
2576 */
2577 fail = true;
2578 if (!narrow_write_error(r1_bio, m)) {
2579 md_error(conf->mddev,
2580 conf->mirrors[m].rdev);
2581 /* an I/O failed, we can't clear the bitmap */
2582 set_bit(R1BIO_Degraded, &r1_bio->state);
2583 }
2584 rdev_dec_pending(conf->mirrors[m].rdev,
2585 conf->mddev);
2586 }
2587 if (fail) {
2588 spin_lock_irq(&conf->device_lock);
2589 list_add(&r1_bio->retry_list, &conf->bio_end_io_list);
2590 idx = sector_to_idx(r1_bio->sector);
2591 atomic_inc(&conf->nr_queued[idx]);
2592 spin_unlock_irq(&conf->device_lock);
2593 /*
2594 * In case freeze_array() is waiting for condition
2595 * get_unqueued_pending() == extra to be true.
2596 */
2597 wake_up(&conf->wait_barrier);
2598 md_wakeup_thread(conf->mddev->thread);
2599 } else {
2600 if (test_bit(R1BIO_WriteError, &r1_bio->state))
2601 close_write(r1_bio);
2602 raid_end_bio_io(r1_bio);
2603 }
2604}
2605
2606static void handle_read_error(struct r1conf *conf, struct r1bio *r1_bio)
2607{
2608 struct mddev *mddev = conf->mddev;
2609 struct bio *bio;
2610 struct md_rdev *rdev;
2611 sector_t sector;
2612
2613 clear_bit(R1BIO_ReadError, &r1_bio->state);
2614 /* we got a read error. Maybe the drive is bad. Maybe just
2615 * the block and we can fix it.
2616 * We freeze all other IO, and try reading the block from
2617 * other devices. When we find one, we re-write
2618 * and check it that fixes the read error.
2619 * This is all done synchronously while the array is
2620 * frozen
2621 */
2622
2623 bio = r1_bio->bios[r1_bio->read_disk];
2624 bio_put(bio);
2625 r1_bio->bios[r1_bio->read_disk] = NULL;
2626
2627 rdev = conf->mirrors[r1_bio->read_disk].rdev;
2628 if (mddev->ro == 0
2629 && !test_bit(FailFast, &rdev->flags)) {
2630 freeze_array(conf, 1);
2631 fix_read_error(conf, r1_bio);
2632 unfreeze_array(conf);
2633 } else if (mddev->ro == 0 && test_bit(FailFast, &rdev->flags)) {
2634 md_error(mddev, rdev);
2635 } else {
2636 r1_bio->bios[r1_bio->read_disk] = IO_BLOCKED;
2637 }
2638
2639 rdev_dec_pending(rdev, conf->mddev);
2640 sector = r1_bio->sector;
2641 bio = r1_bio->master_bio;
2642
2643 /* Reuse the old r1_bio so that the IO_BLOCKED settings are preserved */
2644 r1_bio->state = 0;
2645 raid1_read_request(mddev, bio, r1_bio->sectors, r1_bio);
2646 allow_barrier(conf, sector);
2647}
2648
2649static void raid1d(struct md_thread *thread)
2650{
2651 struct mddev *mddev = thread->mddev;
2652 struct r1bio *r1_bio;
2653 unsigned long flags;
2654 struct r1conf *conf = mddev->private;
2655 struct list_head *head = &conf->retry_list;
2656 struct blk_plug plug;
2657 int idx;
2658
2659 md_check_recovery(mddev);
2660
2661 if (!list_empty_careful(&conf->bio_end_io_list) &&
2662 !test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags)) {
2663 LIST_HEAD(tmp);
2664 spin_lock_irqsave(&conf->device_lock, flags);
2665 if (!test_bit(MD_SB_CHANGE_PENDING, &mddev->sb_flags))
2666 list_splice_init(&conf->bio_end_io_list, &tmp);
2667 spin_unlock_irqrestore(&conf->device_lock, flags);
2668 while (!list_empty(&tmp)) {
2669 r1_bio = list_first_entry(&tmp, struct r1bio,
2670 retry_list);
2671 list_del(&r1_bio->retry_list);
2672 idx = sector_to_idx(r1_bio->sector);
2673 atomic_dec(&conf->nr_queued[idx]);
2674 if (mddev->degraded)
2675 set_bit(R1BIO_Degraded, &r1_bio->state);
2676 if (test_bit(R1BIO_WriteError, &r1_bio->state))
2677 close_write(r1_bio);
2678 raid_end_bio_io(r1_bio);
2679 }
2680 }
2681
2682 blk_start_plug(&plug);
2683 for (;;) {
2684
2685 flush_pending_writes(conf);
2686
2687 spin_lock_irqsave(&conf->device_lock, flags);
2688 if (list_empty(head)) {
2689 spin_unlock_irqrestore(&conf->device_lock, flags);
2690 break;
2691 }
2692 r1_bio = list_entry(head->prev, struct r1bio, retry_list);
2693 list_del(head->prev);
2694 idx = sector_to_idx(r1_bio->sector);
2695 atomic_dec(&conf->nr_queued[idx]);
2696 spin_unlock_irqrestore(&conf->device_lock, flags);
2697
2698 mddev = r1_bio->mddev;
2699 conf = mddev->private;
2700 if (test_bit(R1BIO_IsSync, &r1_bio->state)) {
2701 if (test_bit(R1BIO_MadeGood, &r1_bio->state) ||
2702 test_bit(R1BIO_WriteError, &r1_bio->state))
2703 handle_sync_write_finished(conf, r1_bio);
2704 else
2705 sync_request_write(mddev, r1_bio);
2706 } else if (test_bit(R1BIO_MadeGood, &r1_bio->state) ||
2707 test_bit(R1BIO_WriteError, &r1_bio->state))
2708 handle_write_finished(conf, r1_bio);
2709 else if (test_bit(R1BIO_ReadError, &r1_bio->state))
2710 handle_read_error(conf, r1_bio);
2711 else
2712 WARN_ON_ONCE(1);
2713
2714 cond_resched();
2715 if (mddev->sb_flags & ~(1<<MD_SB_CHANGE_PENDING))
2716 md_check_recovery(mddev);
2717 }
2718 blk_finish_plug(&plug);
2719}
2720
2721static int init_resync(struct r1conf *conf)
2722{
2723 int buffs;
2724
2725 buffs = RESYNC_WINDOW / RESYNC_BLOCK_SIZE;
2726 BUG_ON(mempool_initialized(&conf->r1buf_pool));
2727
2728 return mempool_init(&conf->r1buf_pool, buffs, r1buf_pool_alloc,
2729 r1buf_pool_free, conf->poolinfo);
2730}
2731
2732static struct r1bio *raid1_alloc_init_r1buf(struct r1conf *conf)
2733{
2734 struct r1bio *r1bio = mempool_alloc(&conf->r1buf_pool, GFP_NOIO);
2735 struct resync_pages *rps;
2736 struct bio *bio;
2737 int i;
2738
2739 for (i = conf->poolinfo->raid_disks; i--; ) {
2740 bio = r1bio->bios[i];
2741 rps = bio->bi_private;
2742 bio_reset(bio, NULL, 0);
2743 bio->bi_private = rps;
2744 }
2745 r1bio->master_bio = NULL;
2746 return r1bio;
2747}
2748
2749/*
2750 * perform a "sync" on one "block"
2751 *
2752 * We need to make sure that no normal I/O request - particularly write
2753 * requests - conflict with active sync requests.
2754 *
2755 * This is achieved by tracking pending requests and a 'barrier' concept
2756 * that can be installed to exclude normal IO requests.
2757 */
2758
2759static sector_t raid1_sync_request(struct mddev *mddev, sector_t sector_nr,
2760 int *skipped)
2761{
2762 struct r1conf *conf = mddev->private;
2763 struct r1bio *r1_bio;
2764 struct bio *bio;
2765 sector_t max_sector, nr_sectors;
2766 int disk = -1;
2767 int i;
2768 int wonly = -1;
2769 int write_targets = 0, read_targets = 0;
2770 sector_t sync_blocks;
2771 int still_degraded = 0;
2772 int good_sectors = RESYNC_SECTORS;
2773 int min_bad = 0; /* number of sectors that are bad in all devices */
2774 int idx = sector_to_idx(sector_nr);
2775 int page_idx = 0;
2776
2777 if (!mempool_initialized(&conf->r1buf_pool))
2778 if (init_resync(conf))
2779 return 0;
2780
2781 max_sector = mddev->dev_sectors;
2782 if (sector_nr >= max_sector) {
2783 /* If we aborted, we need to abort the
2784 * sync on the 'current' bitmap chunk (there will
2785 * only be one in raid1 resync.
2786 * We can find the current addess in mddev->curr_resync
2787 */
2788 if (mddev->curr_resync < max_sector) /* aborted */
2789 md_bitmap_end_sync(mddev->bitmap, mddev->curr_resync,
2790 &sync_blocks, 1);
2791 else /* completed sync */
2792 conf->fullsync = 0;
2793
2794 md_bitmap_close_sync(mddev->bitmap);
2795 close_sync(conf);
2796
2797 if (mddev_is_clustered(mddev)) {
2798 conf->cluster_sync_low = 0;
2799 conf->cluster_sync_high = 0;
2800 }
2801 return 0;
2802 }
2803
2804 if (mddev->bitmap == NULL &&
2805 mddev->recovery_cp == MaxSector &&
2806 !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery) &&
2807 conf->fullsync == 0) {
2808 *skipped = 1;
2809 return max_sector - sector_nr;
2810 }
2811 /* before building a request, check if we can skip these blocks..
2812 * This call the bitmap_start_sync doesn't actually record anything
2813 */
2814 if (!md_bitmap_start_sync(mddev->bitmap, sector_nr, &sync_blocks, 1) &&
2815 !conf->fullsync && !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) {
2816 /* We can skip this block, and probably several more */
2817 *skipped = 1;
2818 return sync_blocks;
2819 }
2820
2821 /*
2822 * If there is non-resync activity waiting for a turn, then let it
2823 * though before starting on this new sync request.
2824 */
2825 if (atomic_read(&conf->nr_waiting[idx]))
2826 schedule_timeout_uninterruptible(1);
2827
2828 /* we are incrementing sector_nr below. To be safe, we check against
2829 * sector_nr + two times RESYNC_SECTORS
2830 */
2831
2832 md_bitmap_cond_end_sync(mddev->bitmap, sector_nr,
2833 mddev_is_clustered(mddev) && (sector_nr + 2 * RESYNC_SECTORS > conf->cluster_sync_high));
2834
2835
2836 if (raise_barrier(conf, sector_nr))
2837 return 0;
2838
2839 r1_bio = raid1_alloc_init_r1buf(conf);
2840
2841 /*
2842 * If we get a correctably read error during resync or recovery,
2843 * we might want to read from a different device. So we
2844 * flag all drives that could conceivably be read from for READ,
2845 * and any others (which will be non-In_sync devices) for WRITE.
2846 * If a read fails, we try reading from something else for which READ
2847 * is OK.
2848 */
2849
2850 r1_bio->mddev = mddev;
2851 r1_bio->sector = sector_nr;
2852 r1_bio->state = 0;
2853 set_bit(R1BIO_IsSync, &r1_bio->state);
2854 /* make sure good_sectors won't go across barrier unit boundary */
2855 good_sectors = align_to_barrier_unit_end(sector_nr, good_sectors);
2856
2857 for (i = 0; i < conf->raid_disks * 2; i++) {
2858 struct md_rdev *rdev;
2859 bio = r1_bio->bios[i];
2860
2861 rdev = conf->mirrors[i].rdev;
2862 if (rdev == NULL ||
2863 test_bit(Faulty, &rdev->flags)) {
2864 if (i < conf->raid_disks)
2865 still_degraded = 1;
2866 } else if (!test_bit(In_sync, &rdev->flags)) {
2867 bio->bi_opf = REQ_OP_WRITE;
2868 bio->bi_end_io = end_sync_write;
2869 write_targets ++;
2870 } else {
2871 /* may need to read from here */
2872 sector_t first_bad = MaxSector;
2873 int bad_sectors;
2874
2875 if (is_badblock(rdev, sector_nr, good_sectors,
2876 &first_bad, &bad_sectors)) {
2877 if (first_bad > sector_nr)
2878 good_sectors = first_bad - sector_nr;
2879 else {
2880 bad_sectors -= (sector_nr - first_bad);
2881 if (min_bad == 0 ||
2882 min_bad > bad_sectors)
2883 min_bad = bad_sectors;
2884 }
2885 }
2886 if (sector_nr < first_bad) {
2887 if (test_bit(WriteMostly, &rdev->flags)) {
2888 if (wonly < 0)
2889 wonly = i;
2890 } else {
2891 if (disk < 0)
2892 disk = i;
2893 }
2894 bio->bi_opf = REQ_OP_READ;
2895 bio->bi_end_io = end_sync_read;
2896 read_targets++;
2897 } else if (!test_bit(WriteErrorSeen, &rdev->flags) &&
2898 test_bit(MD_RECOVERY_SYNC, &mddev->recovery) &&
2899 !test_bit(MD_RECOVERY_CHECK, &mddev->recovery)) {
2900 /*
2901 * The device is suitable for reading (InSync),
2902 * but has bad block(s) here. Let's try to correct them,
2903 * if we are doing resync or repair. Otherwise, leave
2904 * this device alone for this sync request.
2905 */
2906 bio->bi_opf = REQ_OP_WRITE;
2907 bio->bi_end_io = end_sync_write;
2908 write_targets++;
2909 }
2910 }
2911 if (rdev && bio->bi_end_io) {
2912 atomic_inc(&rdev->nr_pending);
2913 bio->bi_iter.bi_sector = sector_nr + rdev->data_offset;
2914 bio_set_dev(bio, rdev->bdev);
2915 if (test_bit(FailFast, &rdev->flags))
2916 bio->bi_opf |= MD_FAILFAST;
2917 }
2918 }
2919 if (disk < 0)
2920 disk = wonly;
2921 r1_bio->read_disk = disk;
2922
2923 if (read_targets == 0 && min_bad > 0) {
2924 /* These sectors are bad on all InSync devices, so we
2925 * need to mark them bad on all write targets
2926 */
2927 int ok = 1;
2928 for (i = 0 ; i < conf->raid_disks * 2 ; i++)
2929 if (r1_bio->bios[i]->bi_end_io == end_sync_write) {
2930 struct md_rdev *rdev = conf->mirrors[i].rdev;
2931 ok = rdev_set_badblocks(rdev, sector_nr,
2932 min_bad, 0
2933 ) && ok;
2934 }
2935 set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
2936 *skipped = 1;
2937 put_buf(r1_bio);
2938
2939 if (!ok) {
2940 /* Cannot record the badblocks, so need to
2941 * abort the resync.
2942 * If there are multiple read targets, could just
2943 * fail the really bad ones ???
2944 */
2945 conf->recovery_disabled = mddev->recovery_disabled;
2946 set_bit(MD_RECOVERY_INTR, &mddev->recovery);
2947 return 0;
2948 } else
2949 return min_bad;
2950
2951 }
2952 if (min_bad > 0 && min_bad < good_sectors) {
2953 /* only resync enough to reach the next bad->good
2954 * transition */
2955 good_sectors = min_bad;
2956 }
2957
2958 if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery) && read_targets > 0)
2959 /* extra read targets are also write targets */
2960 write_targets += read_targets-1;
2961
2962 if (write_targets == 0 || read_targets == 0) {
2963 /* There is nowhere to write, so all non-sync
2964 * drives must be failed - so we are finished
2965 */
2966 sector_t rv;
2967 if (min_bad > 0)
2968 max_sector = sector_nr + min_bad;
2969 rv = max_sector - sector_nr;
2970 *skipped = 1;
2971 put_buf(r1_bio);
2972 return rv;
2973 }
2974
2975 if (max_sector > mddev->resync_max)
2976 max_sector = mddev->resync_max; /* Don't do IO beyond here */
2977 if (max_sector > sector_nr + good_sectors)
2978 max_sector = sector_nr + good_sectors;
2979 nr_sectors = 0;
2980 sync_blocks = 0;
2981 do {
2982 struct page *page;
2983 int len = PAGE_SIZE;
2984 if (sector_nr + (len>>9) > max_sector)
2985 len = (max_sector - sector_nr) << 9;
2986 if (len == 0)
2987 break;
2988 if (sync_blocks == 0) {
2989 if (!md_bitmap_start_sync(mddev->bitmap, sector_nr,
2990 &sync_blocks, still_degraded) &&
2991 !conf->fullsync &&
2992 !test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery))
2993 break;
2994 if ((len >> 9) > sync_blocks)
2995 len = sync_blocks<<9;
2996 }
2997
2998 for (i = 0 ; i < conf->raid_disks * 2; i++) {
2999 struct resync_pages *rp;
3000
3001 bio = r1_bio->bios[i];
3002 rp = get_resync_pages(bio);
3003 if (bio->bi_end_io) {
3004 page = resync_fetch_page(rp, page_idx);
3005
3006 /*
3007 * won't fail because the vec table is big
3008 * enough to hold all these pages
3009 */
3010 __bio_add_page(bio, page, len, 0);
3011 }
3012 }
3013 nr_sectors += len>>9;
3014 sector_nr += len>>9;
3015 sync_blocks -= (len>>9);
3016 } while (++page_idx < RESYNC_PAGES);
3017
3018 r1_bio->sectors = nr_sectors;
3019
3020 if (mddev_is_clustered(mddev) &&
3021 conf->cluster_sync_high < sector_nr + nr_sectors) {
3022 conf->cluster_sync_low = mddev->curr_resync_completed;
3023 conf->cluster_sync_high = conf->cluster_sync_low + CLUSTER_RESYNC_WINDOW_SECTORS;
3024 /* Send resync message */
3025 md_cluster_ops->resync_info_update(mddev,
3026 conf->cluster_sync_low,
3027 conf->cluster_sync_high);
3028 }
3029
3030 /* For a user-requested sync, we read all readable devices and do a
3031 * compare
3032 */
3033 if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) {
3034 atomic_set(&r1_bio->remaining, read_targets);
3035 for (i = 0; i < conf->raid_disks * 2 && read_targets; i++) {
3036 bio = r1_bio->bios[i];
3037 if (bio->bi_end_io == end_sync_read) {
3038 read_targets--;
3039 md_sync_acct_bio(bio, nr_sectors);
3040 if (read_targets == 1)
3041 bio->bi_opf &= ~MD_FAILFAST;
3042 submit_bio_noacct(bio);
3043 }
3044 }
3045 } else {
3046 atomic_set(&r1_bio->remaining, 1);
3047 bio = r1_bio->bios[r1_bio->read_disk];
3048 md_sync_acct_bio(bio, nr_sectors);
3049 if (read_targets == 1)
3050 bio->bi_opf &= ~MD_FAILFAST;
3051 submit_bio_noacct(bio);
3052 }
3053 return nr_sectors;
3054}
3055
3056static sector_t raid1_size(struct mddev *mddev, sector_t sectors, int raid_disks)
3057{
3058 if (sectors)
3059 return sectors;
3060
3061 return mddev->dev_sectors;
3062}
3063
3064static struct r1conf *setup_conf(struct mddev *mddev)
3065{
3066 struct r1conf *conf;
3067 int i;
3068 struct raid1_info *disk;
3069 struct md_rdev *rdev;
3070 int err = -ENOMEM;
3071
3072 conf = kzalloc(sizeof(struct r1conf), GFP_KERNEL);
3073 if (!conf)
3074 goto abort;
3075
3076 conf->nr_pending = kcalloc(BARRIER_BUCKETS_NR,
3077 sizeof(atomic_t), GFP_KERNEL);
3078 if (!conf->nr_pending)
3079 goto abort;
3080
3081 conf->nr_waiting = kcalloc(BARRIER_BUCKETS_NR,
3082 sizeof(atomic_t), GFP_KERNEL);
3083 if (!conf->nr_waiting)
3084 goto abort;
3085
3086 conf->nr_queued = kcalloc(BARRIER_BUCKETS_NR,
3087 sizeof(atomic_t), GFP_KERNEL);
3088 if (!conf->nr_queued)
3089 goto abort;
3090
3091 conf->barrier = kcalloc(BARRIER_BUCKETS_NR,
3092 sizeof(atomic_t), GFP_KERNEL);
3093 if (!conf->barrier)
3094 goto abort;
3095
3096 conf->mirrors = kzalloc(array3_size(sizeof(struct raid1_info),
3097 mddev->raid_disks, 2),
3098 GFP_KERNEL);
3099 if (!conf->mirrors)
3100 goto abort;
3101
3102 conf->tmppage = alloc_page(GFP_KERNEL);
3103 if (!conf->tmppage)
3104 goto abort;
3105
3106 conf->poolinfo = kzalloc(sizeof(*conf->poolinfo), GFP_KERNEL);
3107 if (!conf->poolinfo)
3108 goto abort;
3109 conf->poolinfo->raid_disks = mddev->raid_disks * 2;
3110 err = mempool_init(&conf->r1bio_pool, NR_RAID_BIOS, r1bio_pool_alloc,
3111 rbio_pool_free, conf->poolinfo);
3112 if (err)
3113 goto abort;
3114
3115 err = bioset_init(&conf->bio_split, BIO_POOL_SIZE, 0, 0);
3116 if (err)
3117 goto abort;
3118
3119 conf->poolinfo->mddev = mddev;
3120
3121 err = -EINVAL;
3122 spin_lock_init(&conf->device_lock);
3123 conf->raid_disks = mddev->raid_disks;
3124 rdev_for_each(rdev, mddev) {
3125 int disk_idx = rdev->raid_disk;
3126
3127 if (disk_idx >= conf->raid_disks || disk_idx < 0)
3128 continue;
3129
3130 if (!raid1_add_conf(conf, rdev, disk_idx,
3131 test_bit(Replacement, &rdev->flags)))
3132 goto abort;
3133 }
3134 conf->mddev = mddev;
3135 INIT_LIST_HEAD(&conf->retry_list);
3136 INIT_LIST_HEAD(&conf->bio_end_io_list);
3137
3138 spin_lock_init(&conf->resync_lock);
3139 init_waitqueue_head(&conf->wait_barrier);
3140
3141 bio_list_init(&conf->pending_bio_list);
3142 conf->recovery_disabled = mddev->recovery_disabled - 1;
3143
3144 err = -EIO;
3145 for (i = 0; i < conf->raid_disks * 2; i++) {
3146
3147 disk = conf->mirrors + i;
3148
3149 if (i < conf->raid_disks &&
3150 disk[conf->raid_disks].rdev) {
3151 /* This slot has a replacement. */
3152 if (!disk->rdev) {
3153 /* No original, just make the replacement
3154 * a recovering spare
3155 */
3156 disk->rdev =
3157 disk[conf->raid_disks].rdev;
3158 disk[conf->raid_disks].rdev = NULL;
3159 } else if (!test_bit(In_sync, &disk->rdev->flags))
3160 /* Original is not in_sync - bad */
3161 goto abort;
3162 }
3163
3164 if (!disk->rdev ||
3165 !test_bit(In_sync, &disk->rdev->flags)) {
3166 disk->head_position = 0;
3167 if (disk->rdev &&
3168 (disk->rdev->saved_raid_disk < 0))
3169 conf->fullsync = 1;
3170 }
3171 }
3172
3173 err = -ENOMEM;
3174 rcu_assign_pointer(conf->thread,
3175 md_register_thread(raid1d, mddev, "raid1"));
3176 if (!conf->thread)
3177 goto abort;
3178
3179 return conf;
3180
3181 abort:
3182 if (conf) {
3183 mempool_exit(&conf->r1bio_pool);
3184 kfree(conf->mirrors);
3185 safe_put_page(conf->tmppage);
3186 kfree(conf->poolinfo);
3187 kfree(conf->nr_pending);
3188 kfree(conf->nr_waiting);
3189 kfree(conf->nr_queued);
3190 kfree(conf->barrier);
3191 bioset_exit(&conf->bio_split);
3192 kfree(conf);
3193 }
3194 return ERR_PTR(err);
3195}
3196
3197static int raid1_set_limits(struct mddev *mddev)
3198{
3199 struct queue_limits lim;
3200
3201 blk_set_stacking_limits(&lim);
3202 lim.max_write_zeroes_sectors = 0;
3203 mddev_stack_rdev_limits(mddev, &lim);
3204 return queue_limits_set(mddev->gendisk->queue, &lim);
3205}
3206
3207static void raid1_free(struct mddev *mddev, void *priv);
3208static int raid1_run(struct mddev *mddev)
3209{
3210 struct r1conf *conf;
3211 int i;
3212 int ret;
3213
3214 if (mddev->level != 1) {
3215 pr_warn("md/raid1:%s: raid level not set to mirroring (%d)\n",
3216 mdname(mddev), mddev->level);
3217 return -EIO;
3218 }
3219 if (mddev->reshape_position != MaxSector) {
3220 pr_warn("md/raid1:%s: reshape_position set but not supported\n",
3221 mdname(mddev));
3222 return -EIO;
3223 }
3224
3225 /*
3226 * copy the already verified devices into our private RAID1
3227 * bookkeeping area. [whatever we allocate in run(),
3228 * should be freed in raid1_free()]
3229 */
3230 if (mddev->private == NULL)
3231 conf = setup_conf(mddev);
3232 else
3233 conf = mddev->private;
3234
3235 if (IS_ERR(conf))
3236 return PTR_ERR(conf);
3237
3238 if (!mddev_is_dm(mddev)) {
3239 ret = raid1_set_limits(mddev);
3240 if (ret)
3241 goto abort;
3242 }
3243
3244 mddev->degraded = 0;
3245 for (i = 0; i < conf->raid_disks; i++)
3246 if (conf->mirrors[i].rdev == NULL ||
3247 !test_bit(In_sync, &conf->mirrors[i].rdev->flags) ||
3248 test_bit(Faulty, &conf->mirrors[i].rdev->flags))
3249 mddev->degraded++;
3250 /*
3251 * RAID1 needs at least one disk in active
3252 */
3253 if (conf->raid_disks - mddev->degraded < 1) {
3254 md_unregister_thread(mddev, &conf->thread);
3255 ret = -EINVAL;
3256 goto abort;
3257 }
3258
3259 if (conf->raid_disks - mddev->degraded == 1)
3260 mddev->recovery_cp = MaxSector;
3261
3262 if (mddev->recovery_cp != MaxSector)
3263 pr_info("md/raid1:%s: not clean -- starting background reconstruction\n",
3264 mdname(mddev));
3265 pr_info("md/raid1:%s: active with %d out of %d mirrors\n",
3266 mdname(mddev), mddev->raid_disks - mddev->degraded,
3267 mddev->raid_disks);
3268
3269 /*
3270 * Ok, everything is just fine now
3271 */
3272 rcu_assign_pointer(mddev->thread, conf->thread);
3273 rcu_assign_pointer(conf->thread, NULL);
3274 mddev->private = conf;
3275 set_bit(MD_FAILFAST_SUPPORTED, &mddev->flags);
3276
3277 md_set_array_sectors(mddev, raid1_size(mddev, 0, 0));
3278
3279 ret = md_integrity_register(mddev);
3280 if (ret) {
3281 md_unregister_thread(mddev, &mddev->thread);
3282 goto abort;
3283 }
3284 return 0;
3285
3286abort:
3287 raid1_free(mddev, conf);
3288 return ret;
3289}
3290
3291static void raid1_free(struct mddev *mddev, void *priv)
3292{
3293 struct r1conf *conf = priv;
3294
3295 mempool_exit(&conf->r1bio_pool);
3296 kfree(conf->mirrors);
3297 safe_put_page(conf->tmppage);
3298 kfree(conf->poolinfo);
3299 kfree(conf->nr_pending);
3300 kfree(conf->nr_waiting);
3301 kfree(conf->nr_queued);
3302 kfree(conf->barrier);
3303 bioset_exit(&conf->bio_split);
3304 kfree(conf);
3305}
3306
3307static int raid1_resize(struct mddev *mddev, sector_t sectors)
3308{
3309 /* no resync is happening, and there is enough space
3310 * on all devices, so we can resize.
3311 * We need to make sure resync covers any new space.
3312 * If the array is shrinking we should possibly wait until
3313 * any io in the removed space completes, but it hardly seems
3314 * worth it.
3315 */
3316 sector_t newsize = raid1_size(mddev, sectors, 0);
3317 if (mddev->external_size &&
3318 mddev->array_sectors > newsize)
3319 return -EINVAL;
3320 if (mddev->bitmap) {
3321 int ret = md_bitmap_resize(mddev->bitmap, newsize, 0, 0);
3322 if (ret)
3323 return ret;
3324 }
3325 md_set_array_sectors(mddev, newsize);
3326 if (sectors > mddev->dev_sectors &&
3327 mddev->recovery_cp > mddev->dev_sectors) {
3328 mddev->recovery_cp = mddev->dev_sectors;
3329 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3330 }
3331 mddev->dev_sectors = sectors;
3332 mddev->resync_max_sectors = sectors;
3333 return 0;
3334}
3335
3336static int raid1_reshape(struct mddev *mddev)
3337{
3338 /* We need to:
3339 * 1/ resize the r1bio_pool
3340 * 2/ resize conf->mirrors
3341 *
3342 * We allocate a new r1bio_pool if we can.
3343 * Then raise a device barrier and wait until all IO stops.
3344 * Then resize conf->mirrors and swap in the new r1bio pool.
3345 *
3346 * At the same time, we "pack" the devices so that all the missing
3347 * devices have the higher raid_disk numbers.
3348 */
3349 mempool_t newpool, oldpool;
3350 struct pool_info *newpoolinfo;
3351 struct raid1_info *newmirrors;
3352 struct r1conf *conf = mddev->private;
3353 int cnt, raid_disks;
3354 unsigned long flags;
3355 int d, d2;
3356 int ret;
3357
3358 memset(&newpool, 0, sizeof(newpool));
3359 memset(&oldpool, 0, sizeof(oldpool));
3360
3361 /* Cannot change chunk_size, layout, or level */
3362 if (mddev->chunk_sectors != mddev->new_chunk_sectors ||
3363 mddev->layout != mddev->new_layout ||
3364 mddev->level != mddev->new_level) {
3365 mddev->new_chunk_sectors = mddev->chunk_sectors;
3366 mddev->new_layout = mddev->layout;
3367 mddev->new_level = mddev->level;
3368 return -EINVAL;
3369 }
3370
3371 if (!mddev_is_clustered(mddev))
3372 md_allow_write(mddev);
3373
3374 raid_disks = mddev->raid_disks + mddev->delta_disks;
3375
3376 if (raid_disks < conf->raid_disks) {
3377 cnt=0;
3378 for (d= 0; d < conf->raid_disks; d++)
3379 if (conf->mirrors[d].rdev)
3380 cnt++;
3381 if (cnt > raid_disks)
3382 return -EBUSY;
3383 }
3384
3385 newpoolinfo = kmalloc(sizeof(*newpoolinfo), GFP_KERNEL);
3386 if (!newpoolinfo)
3387 return -ENOMEM;
3388 newpoolinfo->mddev = mddev;
3389 newpoolinfo->raid_disks = raid_disks * 2;
3390
3391 ret = mempool_init(&newpool, NR_RAID_BIOS, r1bio_pool_alloc,
3392 rbio_pool_free, newpoolinfo);
3393 if (ret) {
3394 kfree(newpoolinfo);
3395 return ret;
3396 }
3397 newmirrors = kzalloc(array3_size(sizeof(struct raid1_info),
3398 raid_disks, 2),
3399 GFP_KERNEL);
3400 if (!newmirrors) {
3401 kfree(newpoolinfo);
3402 mempool_exit(&newpool);
3403 return -ENOMEM;
3404 }
3405
3406 freeze_array(conf, 0);
3407
3408 /* ok, everything is stopped */
3409 oldpool = conf->r1bio_pool;
3410 conf->r1bio_pool = newpool;
3411
3412 for (d = d2 = 0; d < conf->raid_disks; d++) {
3413 struct md_rdev *rdev = conf->mirrors[d].rdev;
3414 if (rdev && rdev->raid_disk != d2) {
3415 sysfs_unlink_rdev(mddev, rdev);
3416 rdev->raid_disk = d2;
3417 sysfs_unlink_rdev(mddev, rdev);
3418 if (sysfs_link_rdev(mddev, rdev))
3419 pr_warn("md/raid1:%s: cannot register rd%d\n",
3420 mdname(mddev), rdev->raid_disk);
3421 }
3422 if (rdev)
3423 newmirrors[d2++].rdev = rdev;
3424 }
3425 kfree(conf->mirrors);
3426 conf->mirrors = newmirrors;
3427 kfree(conf->poolinfo);
3428 conf->poolinfo = newpoolinfo;
3429
3430 spin_lock_irqsave(&conf->device_lock, flags);
3431 mddev->degraded += (raid_disks - conf->raid_disks);
3432 spin_unlock_irqrestore(&conf->device_lock, flags);
3433 conf->raid_disks = mddev->raid_disks = raid_disks;
3434 mddev->delta_disks = 0;
3435
3436 unfreeze_array(conf);
3437
3438 set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
3439 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3440 md_wakeup_thread(mddev->thread);
3441
3442 mempool_exit(&oldpool);
3443 return 0;
3444}
3445
3446static void raid1_quiesce(struct mddev *mddev, int quiesce)
3447{
3448 struct r1conf *conf = mddev->private;
3449
3450 if (quiesce)
3451 freeze_array(conf, 0);
3452 else
3453 unfreeze_array(conf);
3454}
3455
3456static void *raid1_takeover(struct mddev *mddev)
3457{
3458 /* raid1 can take over:
3459 * raid5 with 2 devices, any layout or chunk size
3460 */
3461 if (mddev->level == 5 && mddev->raid_disks == 2) {
3462 struct r1conf *conf;
3463 mddev->new_level = 1;
3464 mddev->new_layout = 0;
3465 mddev->new_chunk_sectors = 0;
3466 conf = setup_conf(mddev);
3467 if (!IS_ERR(conf)) {
3468 /* Array must appear to be quiesced */
3469 conf->array_frozen = 1;
3470 mddev_clear_unsupported_flags(mddev,
3471 UNSUPPORTED_MDDEV_FLAGS);
3472 }
3473 return conf;
3474 }
3475 return ERR_PTR(-EINVAL);
3476}
3477
3478static struct md_personality raid1_personality =
3479{
3480 .name = "raid1",
3481 .level = 1,
3482 .owner = THIS_MODULE,
3483 .make_request = raid1_make_request,
3484 .run = raid1_run,
3485 .free = raid1_free,
3486 .status = raid1_status,
3487 .error_handler = raid1_error,
3488 .hot_add_disk = raid1_add_disk,
3489 .hot_remove_disk= raid1_remove_disk,
3490 .spare_active = raid1_spare_active,
3491 .sync_request = raid1_sync_request,
3492 .resize = raid1_resize,
3493 .size = raid1_size,
3494 .check_reshape = raid1_reshape,
3495 .quiesce = raid1_quiesce,
3496 .takeover = raid1_takeover,
3497};
3498
3499static int __init raid_init(void)
3500{
3501 return register_md_personality(&raid1_personality);
3502}
3503
3504static void raid_exit(void)
3505{
3506 unregister_md_personality(&raid1_personality);
3507}
3508
3509module_init(raid_init);
3510module_exit(raid_exit);
3511MODULE_LICENSE("GPL");
3512MODULE_DESCRIPTION("RAID1 (mirroring) personality for MD");
3513MODULE_ALIAS("md-personality-3"); /* RAID1 */
3514MODULE_ALIAS("md-raid1");
3515MODULE_ALIAS("md-level-1");