1 /* 2 * Copyright (C) 2010-2011 Neil Brown 3 * Copyright (C) 2010-2015 Red Hat, Inc. All rights reserved. 4 * 5 * This file is released under the GPL. 6 */ 7 8 #include <linux/slab.h> 9 #include <linux/module.h> 10 11 #include "md.h" 12 #include "raid1.h" 13 #include "raid5.h" 14 #include "raid10.h" 15 #include "bitmap.h" 16 17 #include <linux/device-mapper.h> 18 19 #define DM_MSG_PREFIX "raid" 20 #define MAX_RAID_DEVICES 253 /* raid4/5/6 limit */ 21 22 static bool devices_handle_discard_safely = false; 23 24 /* 25 * The following flags are used by dm-raid.c to set up the array state. 26 * They must be cleared before md_run is called. 27 */ 28 #define FirstUse 10 /* rdev flag */ 29 30 struct raid_dev { 31 /* 32 * Two DM devices, one to hold metadata and one to hold the 33 * actual data/parity. The reason for this is to not confuse 34 * ti->len and give more flexibility in altering size and 35 * characteristics. 36 * 37 * While it is possible for this device to be associated 38 * with a different physical device than the data_dev, it 39 * is intended for it to be the same. 40 * |--------- Physical Device ---------| 41 * |- meta_dev -|------ data_dev ------| 42 */ 43 struct dm_dev *meta_dev; 44 struct dm_dev *data_dev; 45 struct md_rdev rdev; 46 }; 47 48 /* 49 * Flags for rs->ctr_flags field. 50 */ 51 #define CTR_FLAG_SYNC 0x1 52 #define CTR_FLAG_NOSYNC 0x2 53 #define CTR_FLAG_REBUILD 0x4 54 #define CTR_FLAG_DAEMON_SLEEP 0x8 55 #define CTR_FLAG_MIN_RECOVERY_RATE 0x10 56 #define CTR_FLAG_MAX_RECOVERY_RATE 0x20 57 #define CTR_FLAG_MAX_WRITE_BEHIND 0x40 58 #define CTR_FLAG_STRIPE_CACHE 0x80 59 #define CTR_FLAG_REGION_SIZE 0x100 60 #define CTR_FLAG_RAID10_COPIES 0x200 61 #define CTR_FLAG_RAID10_FORMAT 0x400 62 63 struct raid_set { 64 struct dm_target *ti; 65 66 uint32_t bitmap_loaded; 67 uint32_t ctr_flags; 68 69 struct mddev md; 70 struct raid_type *raid_type; 71 struct dm_target_callbacks callbacks; 72 73 struct raid_dev dev[0]; 74 }; 75 76 /* Supported raid types and properties. */ 77 static struct raid_type { 78 const char *name; /* RAID algorithm. */ 79 const char *descr; /* Descriptor text for logging. */ 80 const unsigned parity_devs; /* # of parity devices. */ 81 const unsigned minimal_devs; /* minimal # of devices in set. */ 82 const unsigned level; /* RAID level. */ 83 const unsigned algorithm; /* RAID algorithm. */ 84 } raid_types[] = { 85 {"raid0", "RAID0 (striping)", 0, 2, 0, 0 /* NONE */}, 86 {"raid1", "RAID1 (mirroring)", 0, 2, 1, 0 /* NONE */}, 87 {"raid10", "RAID10 (striped mirrors)", 0, 2, 10, UINT_MAX /* Varies */}, 88 {"raid4", "RAID4 (dedicated parity disk)", 1, 2, 5, ALGORITHM_PARITY_0}, 89 {"raid5_la", "RAID5 (left asymmetric)", 1, 2, 5, ALGORITHM_LEFT_ASYMMETRIC}, 90 {"raid5_ra", "RAID5 (right asymmetric)", 1, 2, 5, ALGORITHM_RIGHT_ASYMMETRIC}, 91 {"raid5_ls", "RAID5 (left symmetric)", 1, 2, 5, ALGORITHM_LEFT_SYMMETRIC}, 92 {"raid5_rs", "RAID5 (right symmetric)", 1, 2, 5, ALGORITHM_RIGHT_SYMMETRIC}, 93 {"raid6_zr", "RAID6 (zero restart)", 2, 4, 6, ALGORITHM_ROTATING_ZERO_RESTART}, 94 {"raid6_nr", "RAID6 (N restart)", 2, 4, 6, ALGORITHM_ROTATING_N_RESTART}, 95 {"raid6_nc", "RAID6 (N continue)", 2, 4, 6, ALGORITHM_ROTATING_N_CONTINUE} 96 }; 97 98 static char *raid10_md_layout_to_format(int layout) 99 { 100 /* 101 * Bit 16 and 17 stand for "offset" and "use_far_sets" 102 * Refer to MD's raid10.c for details 103 */ 104 if ((layout & 0x10000) && (layout & 0x20000)) 105 return "offset"; 106 107 if ((layout & 0xFF) > 1) 108 return "near"; 109 110 return "far"; 111 } 112 113 static unsigned raid10_md_layout_to_copies(int layout) 114 { 115 if ((layout & 0xFF) > 1) 116 return layout & 0xFF; 117 return (layout >> 8) & 0xFF; 118 } 119 120 static int raid10_format_to_md_layout(char *format, unsigned copies) 121 { 122 unsigned n = 1, f = 1; 123 124 if (!strcasecmp("near", format)) 125 n = copies; 126 else 127 f = copies; 128 129 if (!strcasecmp("offset", format)) 130 return 0x30000 | (f << 8) | n; 131 132 if (!strcasecmp("far", format)) 133 return 0x20000 | (f << 8) | n; 134 135 return (f << 8) | n; 136 } 137 138 static struct raid_type *get_raid_type(char *name) 139 { 140 int i; 141 142 for (i = 0; i < ARRAY_SIZE(raid_types); i++) 143 if (!strcmp(raid_types[i].name, name)) 144 return &raid_types[i]; 145 146 return NULL; 147 } 148 149 static struct raid_set *context_alloc(struct dm_target *ti, struct raid_type *raid_type, unsigned raid_devs) 150 { 151 unsigned i; 152 struct raid_set *rs; 153 154 if (raid_devs <= raid_type->parity_devs) { 155 ti->error = "Insufficient number of devices"; 156 return ERR_PTR(-EINVAL); 157 } 158 159 rs = kzalloc(sizeof(*rs) + raid_devs * sizeof(rs->dev[0]), GFP_KERNEL); 160 if (!rs) { 161 ti->error = "Cannot allocate raid context"; 162 return ERR_PTR(-ENOMEM); 163 } 164 165 mddev_init(&rs->md); 166 167 rs->ti = ti; 168 rs->raid_type = raid_type; 169 rs->md.raid_disks = raid_devs; 170 rs->md.level = raid_type->level; 171 rs->md.new_level = rs->md.level; 172 rs->md.layout = raid_type->algorithm; 173 rs->md.new_layout = rs->md.layout; 174 rs->md.delta_disks = 0; 175 rs->md.recovery_cp = 0; 176 177 for (i = 0; i < raid_devs; i++) 178 md_rdev_init(&rs->dev[i].rdev); 179 180 /* 181 * Remaining items to be initialized by further RAID params: 182 * rs->md.persistent 183 * rs->md.external 184 * rs->md.chunk_sectors 185 * rs->md.new_chunk_sectors 186 * rs->md.dev_sectors 187 */ 188 189 return rs; 190 } 191 192 static void context_free(struct raid_set *rs) 193 { 194 int i; 195 196 for (i = 0; i < rs->md.raid_disks; i++) { 197 if (rs->dev[i].meta_dev) 198 dm_put_device(rs->ti, rs->dev[i].meta_dev); 199 md_rdev_clear(&rs->dev[i].rdev); 200 if (rs->dev[i].data_dev) 201 dm_put_device(rs->ti, rs->dev[i].data_dev); 202 } 203 204 kfree(rs); 205 } 206 207 /* 208 * For every device we have two words 209 * <meta_dev>: meta device name or '-' if missing 210 * <data_dev>: data device name or '-' if missing 211 * 212 * The following are permitted: 213 * - - 214 * - <data_dev> 215 * <meta_dev> <data_dev> 216 * 217 * The following is not allowed: 218 * <meta_dev> - 219 * 220 * This code parses those words. If there is a failure, 221 * the caller must use context_free to unwind the operations. 222 */ 223 static int dev_parms(struct raid_set *rs, char **argv) 224 { 225 int i; 226 int rebuild = 0; 227 int metadata_available = 0; 228 int ret = 0; 229 230 for (i = 0; i < rs->md.raid_disks; i++, argv += 2) { 231 rs->dev[i].rdev.raid_disk = i; 232 233 rs->dev[i].meta_dev = NULL; 234 rs->dev[i].data_dev = NULL; 235 236 /* 237 * There are no offsets, since there is a separate device 238 * for data and metadata. 239 */ 240 rs->dev[i].rdev.data_offset = 0; 241 rs->dev[i].rdev.mddev = &rs->md; 242 243 if (strcmp(argv[0], "-")) { 244 ret = dm_get_device(rs->ti, argv[0], 245 dm_table_get_mode(rs->ti->table), 246 &rs->dev[i].meta_dev); 247 rs->ti->error = "RAID metadata device lookup failure"; 248 if (ret) 249 return ret; 250 251 rs->dev[i].rdev.sb_page = alloc_page(GFP_KERNEL); 252 if (!rs->dev[i].rdev.sb_page) 253 return -ENOMEM; 254 } 255 256 if (!strcmp(argv[1], "-")) { 257 if (!test_bit(In_sync, &rs->dev[i].rdev.flags) && 258 (!rs->dev[i].rdev.recovery_offset)) { 259 rs->ti->error = "Drive designated for rebuild not specified"; 260 return -EINVAL; 261 } 262 263 rs->ti->error = "No data device supplied with metadata device"; 264 if (rs->dev[i].meta_dev) 265 return -EINVAL; 266 267 continue; 268 } 269 270 ret = dm_get_device(rs->ti, argv[1], 271 dm_table_get_mode(rs->ti->table), 272 &rs->dev[i].data_dev); 273 if (ret) { 274 rs->ti->error = "RAID device lookup failure"; 275 return ret; 276 } 277 278 if (rs->dev[i].meta_dev) { 279 metadata_available = 1; 280 rs->dev[i].rdev.meta_bdev = rs->dev[i].meta_dev->bdev; 281 } 282 rs->dev[i].rdev.bdev = rs->dev[i].data_dev->bdev; 283 list_add(&rs->dev[i].rdev.same_set, &rs->md.disks); 284 if (!test_bit(In_sync, &rs->dev[i].rdev.flags)) 285 rebuild++; 286 } 287 288 if (metadata_available) { 289 rs->md.external = 0; 290 rs->md.persistent = 1; 291 rs->md.major_version = 2; 292 } else if (rebuild && !rs->md.recovery_cp) { 293 /* 294 * Without metadata, we will not be able to tell if the array 295 * is in-sync or not - we must assume it is not. Therefore, 296 * it is impossible to rebuild a drive. 297 * 298 * Even if there is metadata, the on-disk information may 299 * indicate that the array is not in-sync and it will then 300 * fail at that time. 301 * 302 * User could specify 'nosync' option if desperate. 303 */ 304 DMERR("Unable to rebuild drive while array is not in-sync"); 305 rs->ti->error = "RAID device lookup failure"; 306 return -EINVAL; 307 } 308 309 return 0; 310 } 311 312 /* 313 * validate_region_size 314 * @rs 315 * @region_size: region size in sectors. If 0, pick a size (4MiB default). 316 * 317 * Set rs->md.bitmap_info.chunksize (which really refers to 'region size'). 318 * Ensure that (ti->len/region_size < 2^21) - required by MD bitmap. 319 * 320 * Returns: 0 on success, -EINVAL on failure. 321 */ 322 static int validate_region_size(struct raid_set *rs, unsigned long region_size) 323 { 324 unsigned long min_region_size = rs->ti->len / (1 << 21); 325 326 if (!region_size) { 327 /* 328 * Choose a reasonable default. All figures in sectors. 329 */ 330 if (min_region_size > (1 << 13)) { 331 /* If not a power of 2, make it the next power of 2 */ 332 if (min_region_size & (min_region_size - 1)) 333 region_size = 1 << fls(region_size); 334 DMINFO("Choosing default region size of %lu sectors", 335 region_size); 336 } else { 337 DMINFO("Choosing default region size of 4MiB"); 338 region_size = 1 << 13; /* sectors */ 339 } 340 } else { 341 /* 342 * Validate user-supplied value. 343 */ 344 if (region_size > rs->ti->len) { 345 rs->ti->error = "Supplied region size is too large"; 346 return -EINVAL; 347 } 348 349 if (region_size < min_region_size) { 350 DMERR("Supplied region_size (%lu sectors) below minimum (%lu)", 351 region_size, min_region_size); 352 rs->ti->error = "Supplied region size is too small"; 353 return -EINVAL; 354 } 355 356 if (!is_power_of_2(region_size)) { 357 rs->ti->error = "Region size is not a power of 2"; 358 return -EINVAL; 359 } 360 361 if (region_size < rs->md.chunk_sectors) { 362 rs->ti->error = "Region size is smaller than the chunk size"; 363 return -EINVAL; 364 } 365 } 366 367 /* 368 * Convert sectors to bytes. 369 */ 370 rs->md.bitmap_info.chunksize = (region_size << 9); 371 372 return 0; 373 } 374 375 /* 376 * validate_raid_redundancy 377 * @rs 378 * 379 * Determine if there are enough devices in the array that haven't 380 * failed (or are being rebuilt) to form a usable array. 381 * 382 * Returns: 0 on success, -EINVAL on failure. 383 */ 384 static int validate_raid_redundancy(struct raid_set *rs) 385 { 386 unsigned i, rebuild_cnt = 0; 387 unsigned rebuilds_per_group = 0, copies, d; 388 unsigned group_size, last_group_start; 389 390 for (i = 0; i < rs->md.raid_disks; i++) 391 if (!test_bit(In_sync, &rs->dev[i].rdev.flags) || 392 !rs->dev[i].rdev.sb_page) 393 rebuild_cnt++; 394 395 switch (rs->raid_type->level) { 396 case 1: 397 if (rebuild_cnt >= rs->md.raid_disks) 398 goto too_many; 399 break; 400 case 4: 401 case 5: 402 case 6: 403 if (rebuild_cnt > rs->raid_type->parity_devs) 404 goto too_many; 405 break; 406 case 10: 407 copies = raid10_md_layout_to_copies(rs->md.layout); 408 if (rebuild_cnt < copies) 409 break; 410 411 /* 412 * It is possible to have a higher rebuild count for RAID10, 413 * as long as the failed devices occur in different mirror 414 * groups (i.e. different stripes). 415 * 416 * When checking "near" format, make sure no adjacent devices 417 * have failed beyond what can be handled. In addition to the 418 * simple case where the number of devices is a multiple of the 419 * number of copies, we must also handle cases where the number 420 * of devices is not a multiple of the number of copies. 421 * E.g. dev1 dev2 dev3 dev4 dev5 422 * A A B B C 423 * C D D E E 424 */ 425 if (!strcmp("near", raid10_md_layout_to_format(rs->md.layout))) { 426 for (i = 0; i < rs->md.raid_disks * copies; i++) { 427 if (!(i % copies)) 428 rebuilds_per_group = 0; 429 d = i % rs->md.raid_disks; 430 if ((!rs->dev[d].rdev.sb_page || 431 !test_bit(In_sync, &rs->dev[d].rdev.flags)) && 432 (++rebuilds_per_group >= copies)) 433 goto too_many; 434 } 435 break; 436 } 437 438 /* 439 * When checking "far" and "offset" formats, we need to ensure 440 * that the device that holds its copy is not also dead or 441 * being rebuilt. (Note that "far" and "offset" formats only 442 * support two copies right now. These formats also only ever 443 * use the 'use_far_sets' variant.) 444 * 445 * This check is somewhat complicated by the need to account 446 * for arrays that are not a multiple of (far) copies. This 447 * results in the need to treat the last (potentially larger) 448 * set differently. 449 */ 450 group_size = (rs->md.raid_disks / copies); 451 last_group_start = (rs->md.raid_disks / group_size) - 1; 452 last_group_start *= group_size; 453 for (i = 0; i < rs->md.raid_disks; i++) { 454 if (!(i % copies) && !(i > last_group_start)) 455 rebuilds_per_group = 0; 456 if ((!rs->dev[i].rdev.sb_page || 457 !test_bit(In_sync, &rs->dev[i].rdev.flags)) && 458 (++rebuilds_per_group >= copies)) 459 goto too_many; 460 } 461 break; 462 default: 463 if (rebuild_cnt) 464 return -EINVAL; 465 } 466 467 return 0; 468 469 too_many: 470 return -EINVAL; 471 } 472 473 /* 474 * Possible arguments are... 475 * <chunk_size> [optional_args] 476 * 477 * Argument definitions 478 * <chunk_size> The number of sectors per disk that 479 * will form the "stripe" 480 * [[no]sync] Force or prevent recovery of the 481 * entire array 482 * [rebuild <idx>] Rebuild the drive indicated by the index 483 * [daemon_sleep <ms>] Time between bitmap daemon work to 484 * clear bits 485 * [min_recovery_rate <kB/sec/disk>] Throttle RAID initialization 486 * [max_recovery_rate <kB/sec/disk>] Throttle RAID initialization 487 * [write_mostly <idx>] Indicate a write mostly drive via index 488 * [max_write_behind <sectors>] See '-write-behind=' (man mdadm) 489 * [stripe_cache <sectors>] Stripe cache size for higher RAIDs 490 * [region_size <sectors>] Defines granularity of bitmap 491 * 492 * RAID10-only options: 493 * [raid10_copies <# copies>] Number of copies. (Default: 2) 494 * [raid10_format <near|far|offset>] Layout algorithm. (Default: near) 495 */ 496 static int parse_raid_params(struct raid_set *rs, char **argv, 497 unsigned num_raid_params) 498 { 499 char *raid10_format = "near"; 500 unsigned raid10_copies = 2; 501 unsigned i; 502 unsigned long value, region_size = 0; 503 sector_t sectors_per_dev = rs->ti->len; 504 sector_t max_io_len; 505 char *key; 506 507 /* 508 * First, parse the in-order required arguments 509 * "chunk_size" is the only argument of this type. 510 */ 511 if ((kstrtoul(argv[0], 10, &value) < 0)) { 512 rs->ti->error = "Bad chunk size"; 513 return -EINVAL; 514 } else if (rs->raid_type->level == 1) { 515 if (value) 516 DMERR("Ignoring chunk size parameter for RAID 1"); 517 value = 0; 518 } else if (!is_power_of_2(value)) { 519 rs->ti->error = "Chunk size must be a power of 2"; 520 return -EINVAL; 521 } else if (value < 8) { 522 rs->ti->error = "Chunk size value is too small"; 523 return -EINVAL; 524 } 525 526 rs->md.new_chunk_sectors = rs->md.chunk_sectors = value; 527 argv++; 528 num_raid_params--; 529 530 /* 531 * We set each individual device as In_sync with a completed 532 * 'recovery_offset'. If there has been a device failure or 533 * replacement then one of the following cases applies: 534 * 535 * 1) User specifies 'rebuild'. 536 * - Device is reset when param is read. 537 * 2) A new device is supplied. 538 * - No matching superblock found, resets device. 539 * 3) Device failure was transient and returns on reload. 540 * - Failure noticed, resets device for bitmap replay. 541 * 4) Device hadn't completed recovery after previous failure. 542 * - Superblock is read and overrides recovery_offset. 543 * 544 * What is found in the superblocks of the devices is always 545 * authoritative, unless 'rebuild' or '[no]sync' was specified. 546 */ 547 for (i = 0; i < rs->md.raid_disks; i++) { 548 set_bit(In_sync, &rs->dev[i].rdev.flags); 549 rs->dev[i].rdev.recovery_offset = MaxSector; 550 } 551 552 /* 553 * Second, parse the unordered optional arguments 554 */ 555 for (i = 0; i < num_raid_params; i++) { 556 if (!strcasecmp(argv[i], "nosync")) { 557 rs->md.recovery_cp = MaxSector; 558 rs->ctr_flags |= CTR_FLAG_NOSYNC; 559 continue; 560 } 561 if (!strcasecmp(argv[i], "sync")) { 562 rs->md.recovery_cp = 0; 563 rs->ctr_flags |= CTR_FLAG_SYNC; 564 continue; 565 } 566 567 /* The rest of the optional arguments come in key/value pairs */ 568 if ((i + 1) >= num_raid_params) { 569 rs->ti->error = "Wrong number of raid parameters given"; 570 return -EINVAL; 571 } 572 573 key = argv[i++]; 574 575 /* Parameters that take a string value are checked here. */ 576 if (!strcasecmp(key, "raid10_format")) { 577 if (rs->raid_type->level != 10) { 578 rs->ti->error = "'raid10_format' is an invalid parameter for this RAID type"; 579 return -EINVAL; 580 } 581 if (strcmp("near", argv[i]) && 582 strcmp("far", argv[i]) && 583 strcmp("offset", argv[i])) { 584 rs->ti->error = "Invalid 'raid10_format' value given"; 585 return -EINVAL; 586 } 587 raid10_format = argv[i]; 588 rs->ctr_flags |= CTR_FLAG_RAID10_FORMAT; 589 continue; 590 } 591 592 if (kstrtoul(argv[i], 10, &value) < 0) { 593 rs->ti->error = "Bad numerical argument given in raid params"; 594 return -EINVAL; 595 } 596 597 /* Parameters that take a numeric value are checked here */ 598 if (!strcasecmp(key, "rebuild")) { 599 if (value >= rs->md.raid_disks) { 600 rs->ti->error = "Invalid rebuild index given"; 601 return -EINVAL; 602 } 603 clear_bit(In_sync, &rs->dev[value].rdev.flags); 604 rs->dev[value].rdev.recovery_offset = 0; 605 rs->ctr_flags |= CTR_FLAG_REBUILD; 606 } else if (!strcasecmp(key, "write_mostly")) { 607 if (rs->raid_type->level != 1) { 608 rs->ti->error = "write_mostly option is only valid for RAID1"; 609 return -EINVAL; 610 } 611 if (value >= rs->md.raid_disks) { 612 rs->ti->error = "Invalid write_mostly drive index given"; 613 return -EINVAL; 614 } 615 set_bit(WriteMostly, &rs->dev[value].rdev.flags); 616 } else if (!strcasecmp(key, "max_write_behind")) { 617 if (rs->raid_type->level != 1) { 618 rs->ti->error = "max_write_behind option is only valid for RAID1"; 619 return -EINVAL; 620 } 621 rs->ctr_flags |= CTR_FLAG_MAX_WRITE_BEHIND; 622 623 /* 624 * In device-mapper, we specify things in sectors, but 625 * MD records this value in kB 626 */ 627 value /= 2; 628 if (value > COUNTER_MAX) { 629 rs->ti->error = "Max write-behind limit out of range"; 630 return -EINVAL; 631 } 632 rs->md.bitmap_info.max_write_behind = value; 633 } else if (!strcasecmp(key, "daemon_sleep")) { 634 rs->ctr_flags |= CTR_FLAG_DAEMON_SLEEP; 635 if (!value || (value > MAX_SCHEDULE_TIMEOUT)) { 636 rs->ti->error = "daemon sleep period out of range"; 637 return -EINVAL; 638 } 639 rs->md.bitmap_info.daemon_sleep = value; 640 } else if (!strcasecmp(key, "stripe_cache")) { 641 rs->ctr_flags |= CTR_FLAG_STRIPE_CACHE; 642 643 /* 644 * In device-mapper, we specify things in sectors, but 645 * MD records this value in kB 646 */ 647 value /= 2; 648 649 if ((rs->raid_type->level != 5) && 650 (rs->raid_type->level != 6)) { 651 rs->ti->error = "Inappropriate argument: stripe_cache"; 652 return -EINVAL; 653 } 654 if (raid5_set_cache_size(&rs->md, (int)value)) { 655 rs->ti->error = "Bad stripe_cache size"; 656 return -EINVAL; 657 } 658 } else if (!strcasecmp(key, "min_recovery_rate")) { 659 rs->ctr_flags |= CTR_FLAG_MIN_RECOVERY_RATE; 660 if (value > INT_MAX) { 661 rs->ti->error = "min_recovery_rate out of range"; 662 return -EINVAL; 663 } 664 rs->md.sync_speed_min = (int)value; 665 } else if (!strcasecmp(key, "max_recovery_rate")) { 666 rs->ctr_flags |= CTR_FLAG_MAX_RECOVERY_RATE; 667 if (value > INT_MAX) { 668 rs->ti->error = "max_recovery_rate out of range"; 669 return -EINVAL; 670 } 671 rs->md.sync_speed_max = (int)value; 672 } else if (!strcasecmp(key, "region_size")) { 673 rs->ctr_flags |= CTR_FLAG_REGION_SIZE; 674 region_size = value; 675 } else if (!strcasecmp(key, "raid10_copies") && 676 (rs->raid_type->level == 10)) { 677 if ((value < 2) || (value > 0xFF)) { 678 rs->ti->error = "Bad value for 'raid10_copies'"; 679 return -EINVAL; 680 } 681 rs->ctr_flags |= CTR_FLAG_RAID10_COPIES; 682 raid10_copies = value; 683 } else { 684 DMERR("Unable to parse RAID parameter: %s", key); 685 rs->ti->error = "Unable to parse RAID parameters"; 686 return -EINVAL; 687 } 688 } 689 690 if (validate_region_size(rs, region_size)) 691 return -EINVAL; 692 693 if (rs->md.chunk_sectors) 694 max_io_len = rs->md.chunk_sectors; 695 else 696 max_io_len = region_size; 697 698 if (dm_set_target_max_io_len(rs->ti, max_io_len)) 699 return -EINVAL; 700 701 if (rs->raid_type->level == 10) { 702 if (raid10_copies > rs->md.raid_disks) { 703 rs->ti->error = "Not enough devices to satisfy specification"; 704 return -EINVAL; 705 } 706 707 /* 708 * If the format is not "near", we only support 709 * two copies at the moment. 710 */ 711 if (strcmp("near", raid10_format) && (raid10_copies > 2)) { 712 rs->ti->error = "Too many copies for given RAID10 format."; 713 return -EINVAL; 714 } 715 716 /* (Len * #mirrors) / #devices */ 717 sectors_per_dev = rs->ti->len * raid10_copies; 718 sector_div(sectors_per_dev, rs->md.raid_disks); 719 720 rs->md.layout = raid10_format_to_md_layout(raid10_format, 721 raid10_copies); 722 rs->md.new_layout = rs->md.layout; 723 } else if ((!rs->raid_type->level || rs->raid_type->level > 1) && 724 sector_div(sectors_per_dev, 725 (rs->md.raid_disks - rs->raid_type->parity_devs))) { 726 rs->ti->error = "Target length not divisible by number of data devices"; 727 return -EINVAL; 728 } 729 rs->md.dev_sectors = sectors_per_dev; 730 731 /* Assume there are no metadata devices until the drives are parsed */ 732 rs->md.persistent = 0; 733 rs->md.external = 1; 734 735 return 0; 736 } 737 738 static void do_table_event(struct work_struct *ws) 739 { 740 struct raid_set *rs = container_of(ws, struct raid_set, md.event_work); 741 742 dm_table_event(rs->ti->table); 743 } 744 745 static int raid_is_congested(struct dm_target_callbacks *cb, int bits) 746 { 747 struct raid_set *rs = container_of(cb, struct raid_set, callbacks); 748 749 return mddev_congested(&rs->md, bits); 750 } 751 752 /* 753 * This structure is never routinely used by userspace, unlike md superblocks. 754 * Devices with this superblock should only ever be accessed via device-mapper. 755 */ 756 #define DM_RAID_MAGIC 0x64526D44 757 struct dm_raid_superblock { 758 __le32 magic; /* "DmRd" */ 759 __le32 features; /* Used to indicate possible future changes */ 760 761 __le32 num_devices; /* Number of devices in this array. (Max 64) */ 762 __le32 array_position; /* The position of this drive in the array */ 763 764 __le64 events; /* Incremented by md when superblock updated */ 765 __le64 failed_devices; /* Bit field of devices to indicate failures */ 766 767 /* 768 * This offset tracks the progress of the repair or replacement of 769 * an individual drive. 770 */ 771 __le64 disk_recovery_offset; 772 773 /* 774 * This offset tracks the progress of the initial array 775 * synchronisation/parity calculation. 776 */ 777 __le64 array_resync_offset; 778 779 /* 780 * RAID characteristics 781 */ 782 __le32 level; 783 __le32 layout; 784 __le32 stripe_sectors; 785 786 /* Remainder of a logical block is zero-filled when writing (see super_sync()). */ 787 } __packed; 788 789 static int read_disk_sb(struct md_rdev *rdev, int size) 790 { 791 BUG_ON(!rdev->sb_page); 792 793 if (rdev->sb_loaded) 794 return 0; 795 796 if (!sync_page_io(rdev, 0, size, rdev->sb_page, READ, 1)) { 797 DMERR("Failed to read superblock of device at position %d", 798 rdev->raid_disk); 799 md_error(rdev->mddev, rdev); 800 return -EINVAL; 801 } 802 803 rdev->sb_loaded = 1; 804 805 return 0; 806 } 807 808 static void super_sync(struct mddev *mddev, struct md_rdev *rdev) 809 { 810 int i; 811 uint64_t failed_devices; 812 struct dm_raid_superblock *sb; 813 struct raid_set *rs = container_of(mddev, struct raid_set, md); 814 815 sb = page_address(rdev->sb_page); 816 failed_devices = le64_to_cpu(sb->failed_devices); 817 818 for (i = 0; i < mddev->raid_disks; i++) 819 if (!rs->dev[i].data_dev || 820 test_bit(Faulty, &(rs->dev[i].rdev.flags))) 821 failed_devices |= (1ULL << i); 822 823 memset(sb + 1, 0, rdev->sb_size - sizeof(*sb)); 824 825 sb->magic = cpu_to_le32(DM_RAID_MAGIC); 826 sb->features = cpu_to_le32(0); /* No features yet */ 827 828 sb->num_devices = cpu_to_le32(mddev->raid_disks); 829 sb->array_position = cpu_to_le32(rdev->raid_disk); 830 831 sb->events = cpu_to_le64(mddev->events); 832 sb->failed_devices = cpu_to_le64(failed_devices); 833 834 sb->disk_recovery_offset = cpu_to_le64(rdev->recovery_offset); 835 sb->array_resync_offset = cpu_to_le64(mddev->recovery_cp); 836 837 sb->level = cpu_to_le32(mddev->level); 838 sb->layout = cpu_to_le32(mddev->layout); 839 sb->stripe_sectors = cpu_to_le32(mddev->chunk_sectors); 840 } 841 842 /* 843 * super_load 844 * 845 * This function creates a superblock if one is not found on the device 846 * and will decide which superblock to use if there's a choice. 847 * 848 * Return: 1 if use rdev, 0 if use refdev, -Exxx otherwise 849 */ 850 static int super_load(struct md_rdev *rdev, struct md_rdev *refdev) 851 { 852 int ret; 853 struct dm_raid_superblock *sb; 854 struct dm_raid_superblock *refsb; 855 uint64_t events_sb, events_refsb; 856 857 rdev->sb_start = 0; 858 rdev->sb_size = bdev_logical_block_size(rdev->meta_bdev); 859 if (rdev->sb_size < sizeof(*sb) || rdev->sb_size > PAGE_SIZE) { 860 DMERR("superblock size of a logical block is no longer valid"); 861 return -EINVAL; 862 } 863 864 ret = read_disk_sb(rdev, rdev->sb_size); 865 if (ret) 866 return ret; 867 868 sb = page_address(rdev->sb_page); 869 870 /* 871 * Two cases that we want to write new superblocks and rebuild: 872 * 1) New device (no matching magic number) 873 * 2) Device specified for rebuild (!In_sync w/ offset == 0) 874 */ 875 if ((sb->magic != cpu_to_le32(DM_RAID_MAGIC)) || 876 (!test_bit(In_sync, &rdev->flags) && !rdev->recovery_offset)) { 877 super_sync(rdev->mddev, rdev); 878 879 set_bit(FirstUse, &rdev->flags); 880 881 /* Force writing of superblocks to disk */ 882 set_bit(MD_CHANGE_DEVS, &rdev->mddev->flags); 883 884 /* Any superblock is better than none, choose that if given */ 885 return refdev ? 0 : 1; 886 } 887 888 if (!refdev) 889 return 1; 890 891 events_sb = le64_to_cpu(sb->events); 892 893 refsb = page_address(refdev->sb_page); 894 events_refsb = le64_to_cpu(refsb->events); 895 896 return (events_sb > events_refsb) ? 1 : 0; 897 } 898 899 static int super_init_validation(struct mddev *mddev, struct md_rdev *rdev) 900 { 901 int role; 902 struct raid_set *rs = container_of(mddev, struct raid_set, md); 903 uint64_t events_sb; 904 uint64_t failed_devices; 905 struct dm_raid_superblock *sb; 906 uint32_t new_devs = 0; 907 uint32_t rebuilds = 0; 908 struct md_rdev *r; 909 struct dm_raid_superblock *sb2; 910 911 sb = page_address(rdev->sb_page); 912 events_sb = le64_to_cpu(sb->events); 913 failed_devices = le64_to_cpu(sb->failed_devices); 914 915 /* 916 * Initialise to 1 if this is a new superblock. 917 */ 918 mddev->events = events_sb ? : 1; 919 920 /* 921 * Reshaping is not currently allowed 922 */ 923 if (le32_to_cpu(sb->level) != mddev->level) { 924 DMERR("Reshaping arrays not yet supported. (RAID level change)"); 925 return -EINVAL; 926 } 927 if (le32_to_cpu(sb->layout) != mddev->layout) { 928 DMERR("Reshaping arrays not yet supported. (RAID layout change)"); 929 DMERR(" 0x%X vs 0x%X", le32_to_cpu(sb->layout), mddev->layout); 930 DMERR(" Old layout: %s w/ %d copies", 931 raid10_md_layout_to_format(le32_to_cpu(sb->layout)), 932 raid10_md_layout_to_copies(le32_to_cpu(sb->layout))); 933 DMERR(" New layout: %s w/ %d copies", 934 raid10_md_layout_to_format(mddev->layout), 935 raid10_md_layout_to_copies(mddev->layout)); 936 return -EINVAL; 937 } 938 if (le32_to_cpu(sb->stripe_sectors) != mddev->chunk_sectors) { 939 DMERR("Reshaping arrays not yet supported. (stripe sectors change)"); 940 return -EINVAL; 941 } 942 943 /* We can only change the number of devices in RAID1 right now */ 944 if ((rs->raid_type->level != 1) && 945 (le32_to_cpu(sb->num_devices) != mddev->raid_disks)) { 946 DMERR("Reshaping arrays not yet supported. (device count change)"); 947 return -EINVAL; 948 } 949 950 if (!(rs->ctr_flags & (CTR_FLAG_SYNC | CTR_FLAG_NOSYNC))) 951 mddev->recovery_cp = le64_to_cpu(sb->array_resync_offset); 952 953 /* 954 * During load, we set FirstUse if a new superblock was written. 955 * There are two reasons we might not have a superblock: 956 * 1) The array is brand new - in which case, all of the 957 * devices must have their In_sync bit set. Also, 958 * recovery_cp must be 0, unless forced. 959 * 2) This is a new device being added to an old array 960 * and the new device needs to be rebuilt - in which 961 * case the In_sync bit will /not/ be set and 962 * recovery_cp must be MaxSector. 963 */ 964 rdev_for_each(r, mddev) { 965 if (!test_bit(In_sync, &r->flags)) { 966 DMINFO("Device %d specified for rebuild: " 967 "Clearing superblock", r->raid_disk); 968 rebuilds++; 969 } else if (test_bit(FirstUse, &r->flags)) 970 new_devs++; 971 } 972 973 if (!rebuilds) { 974 if (new_devs == mddev->raid_disks) { 975 DMINFO("Superblocks created for new array"); 976 set_bit(MD_ARRAY_FIRST_USE, &mddev->flags); 977 } else if (new_devs) { 978 DMERR("New device injected " 979 "into existing array without 'rebuild' " 980 "parameter specified"); 981 return -EINVAL; 982 } 983 } else if (new_devs) { 984 DMERR("'rebuild' devices cannot be " 985 "injected into an array with other first-time devices"); 986 return -EINVAL; 987 } else if (mddev->recovery_cp != MaxSector) { 988 DMERR("'rebuild' specified while array is not in-sync"); 989 return -EINVAL; 990 } 991 992 /* 993 * Now we set the Faulty bit for those devices that are 994 * recorded in the superblock as failed. 995 */ 996 rdev_for_each(r, mddev) { 997 if (!r->sb_page) 998 continue; 999 sb2 = page_address(r->sb_page); 1000 sb2->failed_devices = 0; 1001 1002 /* 1003 * Check for any device re-ordering. 1004 */ 1005 if (!test_bit(FirstUse, &r->flags) && (r->raid_disk >= 0)) { 1006 role = le32_to_cpu(sb2->array_position); 1007 if (role != r->raid_disk) { 1008 if (rs->raid_type->level != 1) { 1009 rs->ti->error = "Cannot change device " 1010 "positions in RAID array"; 1011 return -EINVAL; 1012 } 1013 DMINFO("RAID1 device #%d now at position #%d", 1014 role, r->raid_disk); 1015 } 1016 1017 /* 1018 * Partial recovery is performed on 1019 * returning failed devices. 1020 */ 1021 if (failed_devices & (1 << role)) 1022 set_bit(Faulty, &r->flags); 1023 } 1024 } 1025 1026 return 0; 1027 } 1028 1029 static int super_validate(struct raid_set *rs, struct md_rdev *rdev) 1030 { 1031 struct mddev *mddev = &rs->md; 1032 struct dm_raid_superblock *sb = page_address(rdev->sb_page); 1033 1034 /* 1035 * If mddev->events is not set, we know we have not yet initialized 1036 * the array. 1037 */ 1038 if (!mddev->events && super_init_validation(mddev, rdev)) 1039 return -EINVAL; 1040 1041 /* Enable bitmap creation for RAID levels != 0 */ 1042 mddev->bitmap_info.offset = (rs->raid_type->level) ? to_sector(4096) : 0; 1043 rdev->mddev->bitmap_info.default_offset = mddev->bitmap_info.offset; 1044 1045 if (!test_bit(FirstUse, &rdev->flags)) { 1046 rdev->recovery_offset = le64_to_cpu(sb->disk_recovery_offset); 1047 if (rdev->recovery_offset != MaxSector) 1048 clear_bit(In_sync, &rdev->flags); 1049 } 1050 1051 /* 1052 * If a device comes back, set it as not In_sync and no longer faulty. 1053 */ 1054 if (test_bit(Faulty, &rdev->flags)) { 1055 clear_bit(Faulty, &rdev->flags); 1056 clear_bit(In_sync, &rdev->flags); 1057 rdev->saved_raid_disk = rdev->raid_disk; 1058 rdev->recovery_offset = 0; 1059 } 1060 1061 clear_bit(FirstUse, &rdev->flags); 1062 1063 return 0; 1064 } 1065 1066 /* 1067 * Analyse superblocks and select the freshest. 1068 */ 1069 static int analyse_superblocks(struct dm_target *ti, struct raid_set *rs) 1070 { 1071 int ret; 1072 struct raid_dev *dev; 1073 struct md_rdev *rdev, *tmp, *freshest; 1074 struct mddev *mddev = &rs->md; 1075 1076 freshest = NULL; 1077 rdev_for_each_safe(rdev, tmp, mddev) { 1078 /* 1079 * Skipping super_load due to CTR_FLAG_SYNC will cause 1080 * the array to undergo initialization again as 1081 * though it were new. This is the intended effect 1082 * of the "sync" directive. 1083 * 1084 * When reshaping capability is added, we must ensure 1085 * that the "sync" directive is disallowed during the 1086 * reshape. 1087 */ 1088 rdev->sectors = to_sector(i_size_read(rdev->bdev->bd_inode)); 1089 1090 if (rs->ctr_flags & CTR_FLAG_SYNC) 1091 continue; 1092 1093 if (!rdev->meta_bdev) 1094 continue; 1095 1096 ret = super_load(rdev, freshest); 1097 1098 switch (ret) { 1099 case 1: 1100 freshest = rdev; 1101 break; 1102 case 0: 1103 break; 1104 default: 1105 dev = container_of(rdev, struct raid_dev, rdev); 1106 if (dev->meta_dev) 1107 dm_put_device(ti, dev->meta_dev); 1108 1109 dev->meta_dev = NULL; 1110 rdev->meta_bdev = NULL; 1111 1112 if (rdev->sb_page) 1113 put_page(rdev->sb_page); 1114 1115 rdev->sb_page = NULL; 1116 1117 rdev->sb_loaded = 0; 1118 1119 /* 1120 * We might be able to salvage the data device 1121 * even though the meta device has failed. For 1122 * now, we behave as though '- -' had been 1123 * set for this device in the table. 1124 */ 1125 if (dev->data_dev) 1126 dm_put_device(ti, dev->data_dev); 1127 1128 dev->data_dev = NULL; 1129 rdev->bdev = NULL; 1130 1131 list_del(&rdev->same_set); 1132 } 1133 } 1134 1135 if (!freshest) 1136 return 0; 1137 1138 if (validate_raid_redundancy(rs)) { 1139 rs->ti->error = "Insufficient redundancy to activate array"; 1140 return -EINVAL; 1141 } 1142 1143 /* 1144 * Validation of the freshest device provides the source of 1145 * validation for the remaining devices. 1146 */ 1147 ti->error = "Unable to assemble array: Invalid superblocks"; 1148 if (super_validate(rs, freshest)) 1149 return -EINVAL; 1150 1151 rdev_for_each(rdev, mddev) 1152 if ((rdev != freshest) && super_validate(rs, rdev)) 1153 return -EINVAL; 1154 1155 return 0; 1156 } 1157 1158 /* 1159 * Enable/disable discard support on RAID set depending on 1160 * RAID level and discard properties of underlying RAID members. 1161 */ 1162 static void configure_discard_support(struct dm_target *ti, struct raid_set *rs) 1163 { 1164 int i; 1165 bool raid456; 1166 1167 /* Assume discards not supported until after checks below. */ 1168 ti->discards_supported = false; 1169 1170 /* RAID level 4,5,6 require discard_zeroes_data for data integrity! */ 1171 raid456 = (rs->md.level == 4 || rs->md.level == 5 || rs->md.level == 6); 1172 1173 for (i = 0; i < rs->md.raid_disks; i++) { 1174 struct request_queue *q; 1175 1176 if (!rs->dev[i].rdev.bdev) 1177 continue; 1178 1179 q = bdev_get_queue(rs->dev[i].rdev.bdev); 1180 if (!q || !blk_queue_discard(q)) 1181 return; 1182 1183 if (raid456) { 1184 if (!q->limits.discard_zeroes_data) 1185 return; 1186 if (!devices_handle_discard_safely) { 1187 DMERR("raid456 discard support disabled due to discard_zeroes_data uncertainty."); 1188 DMERR("Set dm-raid.devices_handle_discard_safely=Y to override."); 1189 return; 1190 } 1191 } 1192 } 1193 1194 /* All RAID members properly support discards */ 1195 ti->discards_supported = true; 1196 1197 /* 1198 * RAID1 and RAID10 personalities require bio splitting, 1199 * RAID0/4/5/6 don't and process large discard bios properly. 1200 */ 1201 ti->split_discard_bios = !!(rs->md.level == 1 || rs->md.level == 10); 1202 ti->num_discard_bios = 1; 1203 } 1204 1205 /* 1206 * Construct a RAID4/5/6 mapping: 1207 * Args: 1208 * <raid_type> <#raid_params> <raid_params> \ 1209 * <#raid_devs> { <meta_dev1> <dev1> .. <meta_devN> <devN> } 1210 * 1211 * <raid_params> varies by <raid_type>. See 'parse_raid_params' for 1212 * details on possible <raid_params>. 1213 */ 1214 static int raid_ctr(struct dm_target *ti, unsigned argc, char **argv) 1215 { 1216 int ret; 1217 struct raid_type *rt; 1218 unsigned long num_raid_params, num_raid_devs; 1219 struct raid_set *rs = NULL; 1220 1221 /* Must have at least <raid_type> <#raid_params> */ 1222 if (argc < 2) { 1223 ti->error = "Too few arguments"; 1224 return -EINVAL; 1225 } 1226 1227 /* raid type */ 1228 rt = get_raid_type(argv[0]); 1229 if (!rt) { 1230 ti->error = "Unrecognised raid_type"; 1231 return -EINVAL; 1232 } 1233 argc--; 1234 argv++; 1235 1236 /* number of RAID parameters */ 1237 if (kstrtoul(argv[0], 10, &num_raid_params) < 0) { 1238 ti->error = "Cannot understand number of RAID parameters"; 1239 return -EINVAL; 1240 } 1241 argc--; 1242 argv++; 1243 1244 /* Skip over RAID params for now and find out # of devices */ 1245 if (num_raid_params >= argc) { 1246 ti->error = "Arguments do not agree with counts given"; 1247 return -EINVAL; 1248 } 1249 1250 if ((kstrtoul(argv[num_raid_params], 10, &num_raid_devs) < 0) || 1251 (num_raid_devs > MAX_RAID_DEVICES)) { 1252 ti->error = "Cannot understand number of raid devices"; 1253 return -EINVAL; 1254 } 1255 1256 argc -= num_raid_params + 1; /* +1: we already have num_raid_devs */ 1257 if (argc != (num_raid_devs * 2)) { 1258 ti->error = "Supplied RAID devices does not match the count given"; 1259 return -EINVAL; 1260 } 1261 1262 rs = context_alloc(ti, rt, (unsigned)num_raid_devs); 1263 if (IS_ERR(rs)) 1264 return PTR_ERR(rs); 1265 1266 ret = parse_raid_params(rs, argv, (unsigned)num_raid_params); 1267 if (ret) 1268 goto bad; 1269 1270 argv += num_raid_params + 1; 1271 1272 ret = dev_parms(rs, argv); 1273 if (ret) 1274 goto bad; 1275 1276 rs->md.sync_super = super_sync; 1277 ret = analyse_superblocks(ti, rs); 1278 if (ret) 1279 goto bad; 1280 1281 INIT_WORK(&rs->md.event_work, do_table_event); 1282 ti->private = rs; 1283 ti->num_flush_bios = 1; 1284 1285 /* 1286 * Disable/enable discard support on RAID set. 1287 */ 1288 configure_discard_support(ti, rs); 1289 1290 /* Has to be held on running the array */ 1291 mddev_lock_nointr(&rs->md); 1292 ret = md_run(&rs->md); 1293 rs->md.in_sync = 0; /* Assume already marked dirty */ 1294 mddev_unlock(&rs->md); 1295 1296 if (ret) { 1297 ti->error = "Fail to run raid array"; 1298 goto bad; 1299 } 1300 1301 if (ti->len != rs->md.array_sectors) { 1302 ti->error = "Array size does not match requested target length"; 1303 ret = -EINVAL; 1304 goto size_mismatch; 1305 } 1306 rs->callbacks.congested_fn = raid_is_congested; 1307 dm_table_add_target_callbacks(ti->table, &rs->callbacks); 1308 1309 mddev_suspend(&rs->md); 1310 return 0; 1311 1312 size_mismatch: 1313 md_stop(&rs->md); 1314 bad: 1315 context_free(rs); 1316 1317 return ret; 1318 } 1319 1320 static void raid_dtr(struct dm_target *ti) 1321 { 1322 struct raid_set *rs = ti->private; 1323 1324 list_del_init(&rs->callbacks.list); 1325 md_stop(&rs->md); 1326 context_free(rs); 1327 } 1328 1329 static int raid_map(struct dm_target *ti, struct bio *bio) 1330 { 1331 struct raid_set *rs = ti->private; 1332 struct mddev *mddev = &rs->md; 1333 1334 mddev->pers->make_request(mddev, bio); 1335 1336 return DM_MAPIO_SUBMITTED; 1337 } 1338 1339 static const char *decipher_sync_action(struct mddev *mddev) 1340 { 1341 if (test_bit(MD_RECOVERY_FROZEN, &mddev->recovery)) 1342 return "frozen"; 1343 1344 if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) || 1345 (!mddev->ro && test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))) { 1346 if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)) 1347 return "reshape"; 1348 1349 if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) { 1350 if (!test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) 1351 return "resync"; 1352 else if (test_bit(MD_RECOVERY_CHECK, &mddev->recovery)) 1353 return "check"; 1354 return "repair"; 1355 } 1356 1357 if (test_bit(MD_RECOVERY_RECOVER, &mddev->recovery)) 1358 return "recover"; 1359 } 1360 1361 return "idle"; 1362 } 1363 1364 static void raid_status(struct dm_target *ti, status_type_t type, 1365 unsigned status_flags, char *result, unsigned maxlen) 1366 { 1367 struct raid_set *rs = ti->private; 1368 unsigned raid_param_cnt = 1; /* at least 1 for chunksize */ 1369 unsigned sz = 0; 1370 int i, array_in_sync = 0; 1371 sector_t sync; 1372 1373 switch (type) { 1374 case STATUSTYPE_INFO: 1375 DMEMIT("%s %d ", rs->raid_type->name, rs->md.raid_disks); 1376 1377 if (rs->raid_type->level) { 1378 if (test_bit(MD_RECOVERY_RUNNING, &rs->md.recovery)) 1379 sync = rs->md.curr_resync_completed; 1380 else 1381 sync = rs->md.recovery_cp; 1382 1383 if (sync >= rs->md.resync_max_sectors) { 1384 /* 1385 * Sync complete. 1386 */ 1387 array_in_sync = 1; 1388 sync = rs->md.resync_max_sectors; 1389 } else if (test_bit(MD_RECOVERY_REQUESTED, &rs->md.recovery)) { 1390 /* 1391 * If "check" or "repair" is occurring, the array has 1392 * undergone and initial sync and the health characters 1393 * should not be 'a' anymore. 1394 */ 1395 array_in_sync = 1; 1396 } else { 1397 /* 1398 * The array may be doing an initial sync, or it may 1399 * be rebuilding individual components. If all the 1400 * devices are In_sync, then it is the array that is 1401 * being initialized. 1402 */ 1403 for (i = 0; i < rs->md.raid_disks; i++) 1404 if (!test_bit(In_sync, &rs->dev[i].rdev.flags)) 1405 array_in_sync = 1; 1406 } 1407 } else { 1408 /* RAID0 */ 1409 array_in_sync = 1; 1410 sync = rs->md.resync_max_sectors; 1411 } 1412 1413 /* 1414 * Status characters: 1415 * 'D' = Dead/Failed device 1416 * 'a' = Alive but not in-sync 1417 * 'A' = Alive and in-sync 1418 */ 1419 for (i = 0; i < rs->md.raid_disks; i++) { 1420 if (test_bit(Faulty, &rs->dev[i].rdev.flags)) 1421 DMEMIT("D"); 1422 else if (!array_in_sync || 1423 !test_bit(In_sync, &rs->dev[i].rdev.flags)) 1424 DMEMIT("a"); 1425 else 1426 DMEMIT("A"); 1427 } 1428 1429 /* 1430 * In-sync ratio: 1431 * The in-sync ratio shows the progress of: 1432 * - Initializing the array 1433 * - Rebuilding a subset of devices of the array 1434 * The user can distinguish between the two by referring 1435 * to the status characters. 1436 */ 1437 DMEMIT(" %llu/%llu", 1438 (unsigned long long) sync, 1439 (unsigned long long) rs->md.resync_max_sectors); 1440 1441 /* 1442 * Sync action: 1443 * See Documentation/device-mapper/dm-raid.c for 1444 * information on each of these states. 1445 */ 1446 DMEMIT(" %s", decipher_sync_action(&rs->md)); 1447 1448 /* 1449 * resync_mismatches/mismatch_cnt 1450 * This field shows the number of discrepancies found when 1451 * performing a "check" of the array. 1452 */ 1453 DMEMIT(" %llu", 1454 (strcmp(rs->md.last_sync_action, "check")) ? 0 : 1455 (unsigned long long) 1456 atomic64_read(&rs->md.resync_mismatches)); 1457 break; 1458 case STATUSTYPE_TABLE: 1459 /* The string you would use to construct this array */ 1460 for (i = 0; i < rs->md.raid_disks; i++) { 1461 if ((rs->ctr_flags & CTR_FLAG_REBUILD) && 1462 rs->dev[i].data_dev && 1463 !test_bit(In_sync, &rs->dev[i].rdev.flags)) 1464 raid_param_cnt += 2; /* for rebuilds */ 1465 if (rs->dev[i].data_dev && 1466 test_bit(WriteMostly, &rs->dev[i].rdev.flags)) 1467 raid_param_cnt += 2; 1468 } 1469 1470 raid_param_cnt += (hweight32(rs->ctr_flags & ~CTR_FLAG_REBUILD) * 2); 1471 if (rs->ctr_flags & (CTR_FLAG_SYNC | CTR_FLAG_NOSYNC)) 1472 raid_param_cnt--; 1473 1474 DMEMIT("%s %u %u", rs->raid_type->name, 1475 raid_param_cnt, rs->md.chunk_sectors); 1476 1477 if ((rs->ctr_flags & CTR_FLAG_SYNC) && 1478 (rs->md.recovery_cp == MaxSector)) 1479 DMEMIT(" sync"); 1480 if (rs->ctr_flags & CTR_FLAG_NOSYNC) 1481 DMEMIT(" nosync"); 1482 1483 for (i = 0; i < rs->md.raid_disks; i++) 1484 if ((rs->ctr_flags & CTR_FLAG_REBUILD) && 1485 rs->dev[i].data_dev && 1486 !test_bit(In_sync, &rs->dev[i].rdev.flags)) 1487 DMEMIT(" rebuild %u", i); 1488 1489 if (rs->ctr_flags & CTR_FLAG_DAEMON_SLEEP) 1490 DMEMIT(" daemon_sleep %lu", 1491 rs->md.bitmap_info.daemon_sleep); 1492 1493 if (rs->ctr_flags & CTR_FLAG_MIN_RECOVERY_RATE) 1494 DMEMIT(" min_recovery_rate %d", rs->md.sync_speed_min); 1495 1496 if (rs->ctr_flags & CTR_FLAG_MAX_RECOVERY_RATE) 1497 DMEMIT(" max_recovery_rate %d", rs->md.sync_speed_max); 1498 1499 for (i = 0; i < rs->md.raid_disks; i++) 1500 if (rs->dev[i].data_dev && 1501 test_bit(WriteMostly, &rs->dev[i].rdev.flags)) 1502 DMEMIT(" write_mostly %u", i); 1503 1504 if (rs->ctr_flags & CTR_FLAG_MAX_WRITE_BEHIND) 1505 DMEMIT(" max_write_behind %lu", 1506 rs->md.bitmap_info.max_write_behind); 1507 1508 if (rs->ctr_flags & CTR_FLAG_STRIPE_CACHE) { 1509 struct r5conf *conf = rs->md.private; 1510 1511 /* convert from kiB to sectors */ 1512 DMEMIT(" stripe_cache %d", 1513 conf ? conf->max_nr_stripes * 2 : 0); 1514 } 1515 1516 if (rs->ctr_flags & CTR_FLAG_REGION_SIZE) 1517 DMEMIT(" region_size %lu", 1518 rs->md.bitmap_info.chunksize >> 9); 1519 1520 if (rs->ctr_flags & CTR_FLAG_RAID10_COPIES) 1521 DMEMIT(" raid10_copies %u", 1522 raid10_md_layout_to_copies(rs->md.layout)); 1523 1524 if (rs->ctr_flags & CTR_FLAG_RAID10_FORMAT) 1525 DMEMIT(" raid10_format %s", 1526 raid10_md_layout_to_format(rs->md.layout)); 1527 1528 DMEMIT(" %d", rs->md.raid_disks); 1529 for (i = 0; i < rs->md.raid_disks; i++) { 1530 if (rs->dev[i].meta_dev) 1531 DMEMIT(" %s", rs->dev[i].meta_dev->name); 1532 else 1533 DMEMIT(" -"); 1534 1535 if (rs->dev[i].data_dev) 1536 DMEMIT(" %s", rs->dev[i].data_dev->name); 1537 else 1538 DMEMIT(" -"); 1539 } 1540 } 1541 } 1542 1543 static int raid_message(struct dm_target *ti, unsigned argc, char **argv) 1544 { 1545 struct raid_set *rs = ti->private; 1546 struct mddev *mddev = &rs->md; 1547 1548 if (!strcasecmp(argv[0], "reshape")) { 1549 DMERR("Reshape not supported."); 1550 return -EINVAL; 1551 } 1552 1553 if (!mddev->pers || !mddev->pers->sync_request) 1554 return -EINVAL; 1555 1556 if (!strcasecmp(argv[0], "frozen")) 1557 set_bit(MD_RECOVERY_FROZEN, &mddev->recovery); 1558 else 1559 clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery); 1560 1561 if (!strcasecmp(argv[0], "idle") || !strcasecmp(argv[0], "frozen")) { 1562 if (mddev->sync_thread) { 1563 set_bit(MD_RECOVERY_INTR, &mddev->recovery); 1564 md_reap_sync_thread(mddev); 1565 } 1566 } else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) || 1567 test_bit(MD_RECOVERY_NEEDED, &mddev->recovery)) 1568 return -EBUSY; 1569 else if (!strcasecmp(argv[0], "resync")) 1570 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); 1571 else if (!strcasecmp(argv[0], "recover")) { 1572 set_bit(MD_RECOVERY_RECOVER, &mddev->recovery); 1573 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); 1574 } else { 1575 if (!strcasecmp(argv[0], "check")) 1576 set_bit(MD_RECOVERY_CHECK, &mddev->recovery); 1577 else if (!!strcasecmp(argv[0], "repair")) 1578 return -EINVAL; 1579 set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery); 1580 set_bit(MD_RECOVERY_SYNC, &mddev->recovery); 1581 } 1582 if (mddev->ro == 2) { 1583 /* A write to sync_action is enough to justify 1584 * canceling read-auto mode 1585 */ 1586 mddev->ro = 0; 1587 if (!mddev->suspended) 1588 md_wakeup_thread(mddev->sync_thread); 1589 } 1590 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); 1591 if (!mddev->suspended) 1592 md_wakeup_thread(mddev->thread); 1593 1594 return 0; 1595 } 1596 1597 static int raid_iterate_devices(struct dm_target *ti, 1598 iterate_devices_callout_fn fn, void *data) 1599 { 1600 struct raid_set *rs = ti->private; 1601 unsigned i; 1602 int ret = 0; 1603 1604 for (i = 0; !ret && i < rs->md.raid_disks; i++) 1605 if (rs->dev[i].data_dev) 1606 ret = fn(ti, 1607 rs->dev[i].data_dev, 1608 0, /* No offset on data devs */ 1609 rs->md.dev_sectors, 1610 data); 1611 1612 return ret; 1613 } 1614 1615 static void raid_io_hints(struct dm_target *ti, struct queue_limits *limits) 1616 { 1617 struct raid_set *rs = ti->private; 1618 unsigned chunk_size = rs->md.chunk_sectors << 9; 1619 struct r5conf *conf = rs->md.private; 1620 1621 blk_limits_io_min(limits, chunk_size); 1622 blk_limits_io_opt(limits, chunk_size * (conf->raid_disks - conf->max_degraded)); 1623 } 1624 1625 static void raid_presuspend(struct dm_target *ti) 1626 { 1627 struct raid_set *rs = ti->private; 1628 1629 md_stop_writes(&rs->md); 1630 } 1631 1632 static void raid_postsuspend(struct dm_target *ti) 1633 { 1634 struct raid_set *rs = ti->private; 1635 1636 mddev_suspend(&rs->md); 1637 } 1638 1639 static void attempt_restore_of_faulty_devices(struct raid_set *rs) 1640 { 1641 int i; 1642 uint64_t failed_devices, cleared_failed_devices = 0; 1643 unsigned long flags; 1644 struct dm_raid_superblock *sb; 1645 struct md_rdev *r; 1646 1647 for (i = 0; i < rs->md.raid_disks; i++) { 1648 r = &rs->dev[i].rdev; 1649 if (test_bit(Faulty, &r->flags) && r->sb_page && 1650 sync_page_io(r, 0, r->sb_size, r->sb_page, READ, 1)) { 1651 DMINFO("Faulty %s device #%d has readable super block." 1652 " Attempting to revive it.", 1653 rs->raid_type->name, i); 1654 1655 /* 1656 * Faulty bit may be set, but sometimes the array can 1657 * be suspended before the personalities can respond 1658 * by removing the device from the array (i.e. calling 1659 * 'hot_remove_disk'). If they haven't yet removed 1660 * the failed device, its 'raid_disk' number will be 1661 * '>= 0' - meaning we must call this function 1662 * ourselves. 1663 */ 1664 if ((r->raid_disk >= 0) && 1665 (r->mddev->pers->hot_remove_disk(r->mddev, r) != 0)) 1666 /* Failed to revive this device, try next */ 1667 continue; 1668 1669 r->raid_disk = i; 1670 r->saved_raid_disk = i; 1671 flags = r->flags; 1672 clear_bit(Faulty, &r->flags); 1673 clear_bit(WriteErrorSeen, &r->flags); 1674 clear_bit(In_sync, &r->flags); 1675 if (r->mddev->pers->hot_add_disk(r->mddev, r)) { 1676 r->raid_disk = -1; 1677 r->saved_raid_disk = -1; 1678 r->flags = flags; 1679 } else { 1680 r->recovery_offset = 0; 1681 cleared_failed_devices |= 1 << i; 1682 } 1683 } 1684 } 1685 if (cleared_failed_devices) { 1686 rdev_for_each(r, &rs->md) { 1687 sb = page_address(r->sb_page); 1688 failed_devices = le64_to_cpu(sb->failed_devices); 1689 failed_devices &= ~cleared_failed_devices; 1690 sb->failed_devices = cpu_to_le64(failed_devices); 1691 } 1692 } 1693 } 1694 1695 static void raid_resume(struct dm_target *ti) 1696 { 1697 struct raid_set *rs = ti->private; 1698 1699 if (rs->raid_type->level) { 1700 set_bit(MD_CHANGE_DEVS, &rs->md.flags); 1701 1702 if (!rs->bitmap_loaded) { 1703 bitmap_load(&rs->md); 1704 rs->bitmap_loaded = 1; 1705 } else { 1706 /* 1707 * A secondary resume while the device is active. 1708 * Take this opportunity to check whether any failed 1709 * devices are reachable again. 1710 */ 1711 attempt_restore_of_faulty_devices(rs); 1712 } 1713 1714 clear_bit(MD_RECOVERY_FROZEN, &rs->md.recovery); 1715 } 1716 1717 mddev_resume(&rs->md); 1718 } 1719 1720 static struct target_type raid_target = { 1721 .name = "raid", 1722 .version = {1, 7, 0}, 1723 .module = THIS_MODULE, 1724 .ctr = raid_ctr, 1725 .dtr = raid_dtr, 1726 .map = raid_map, 1727 .status = raid_status, 1728 .message = raid_message, 1729 .iterate_devices = raid_iterate_devices, 1730 .io_hints = raid_io_hints, 1731 .presuspend = raid_presuspend, 1732 .postsuspend = raid_postsuspend, 1733 .resume = raid_resume, 1734 }; 1735 1736 static int __init dm_raid_init(void) 1737 { 1738 DMINFO("Loading target version %u.%u.%u", 1739 raid_target.version[0], 1740 raid_target.version[1], 1741 raid_target.version[2]); 1742 return dm_register_target(&raid_target); 1743 } 1744 1745 static void __exit dm_raid_exit(void) 1746 { 1747 dm_unregister_target(&raid_target); 1748 } 1749 1750 module_init(dm_raid_init); 1751 module_exit(dm_raid_exit); 1752 1753 module_param(devices_handle_discard_safely, bool, 0644); 1754 MODULE_PARM_DESC(devices_handle_discard_safely, 1755 "Set to Y if all devices in each array reliably return zeroes on reads from discarded regions"); 1756 1757 MODULE_DESCRIPTION(DM_NAME " raid4/5/6 target"); 1758 MODULE_ALIAS("dm-raid1"); 1759 MODULE_ALIAS("dm-raid10"); 1760 MODULE_ALIAS("dm-raid4"); 1761 MODULE_ALIAS("dm-raid5"); 1762 MODULE_ALIAS("dm-raid6"); 1763 MODULE_AUTHOR("Neil Brown <dm-devel@redhat.com>"); 1764 MODULE_LICENSE("GPL"); 1765