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