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 region_size = roundup_pow_of_two(min_region_size); 333 DMINFO("Choosing default region size of %lu sectors", 334 region_size); 335 } else { 336 DMINFO("Choosing default region size of 4MiB"); 337 region_size = 1 << 13; /* sectors */ 338 } 339 } else { 340 /* 341 * Validate user-supplied value. 342 */ 343 if (region_size > rs->ti->len) { 344 rs->ti->error = "Supplied region size is too large"; 345 return -EINVAL; 346 } 347 348 if (region_size < min_region_size) { 349 DMERR("Supplied region_size (%lu sectors) below minimum (%lu)", 350 region_size, min_region_size); 351 rs->ti->error = "Supplied region size is too small"; 352 return -EINVAL; 353 } 354 355 if (!is_power_of_2(region_size)) { 356 rs->ti->error = "Region size is not a power of 2"; 357 return -EINVAL; 358 } 359 360 if (region_size < rs->md.chunk_sectors) { 361 rs->ti->error = "Region size is smaller than the chunk size"; 362 return -EINVAL; 363 } 364 } 365 366 /* 367 * Convert sectors to bytes. 368 */ 369 rs->md.bitmap_info.chunksize = (region_size << 9); 370 371 return 0; 372 } 373 374 /* 375 * validate_raid_redundancy 376 * @rs 377 * 378 * Determine if there are enough devices in the array that haven't 379 * failed (or are being rebuilt) to form a usable array. 380 * 381 * Returns: 0 on success, -EINVAL on failure. 382 */ 383 static int validate_raid_redundancy(struct raid_set *rs) 384 { 385 unsigned i, rebuild_cnt = 0; 386 unsigned rebuilds_per_group = 0, copies, d; 387 unsigned group_size, last_group_start; 388 389 for (i = 0; i < rs->md.raid_disks; i++) 390 if (!test_bit(In_sync, &rs->dev[i].rdev.flags) || 391 !rs->dev[i].rdev.sb_page) 392 rebuild_cnt++; 393 394 switch (rs->raid_type->level) { 395 case 1: 396 if (rebuild_cnt >= rs->md.raid_disks) 397 goto too_many; 398 break; 399 case 4: 400 case 5: 401 case 6: 402 if (rebuild_cnt > rs->raid_type->parity_devs) 403 goto too_many; 404 break; 405 case 10: 406 copies = raid10_md_layout_to_copies(rs->md.layout); 407 if (rebuild_cnt < copies) 408 break; 409 410 /* 411 * It is possible to have a higher rebuild count for RAID10, 412 * as long as the failed devices occur in different mirror 413 * groups (i.e. different stripes). 414 * 415 * When checking "near" format, make sure no adjacent devices 416 * have failed beyond what can be handled. In addition to the 417 * simple case where the number of devices is a multiple of the 418 * number of copies, we must also handle cases where the number 419 * of devices is not a multiple of the number of copies. 420 * E.g. dev1 dev2 dev3 dev4 dev5 421 * A A B B C 422 * C D D E E 423 */ 424 if (!strcmp("near", raid10_md_layout_to_format(rs->md.layout))) { 425 for (i = 0; i < rs->md.raid_disks * copies; i++) { 426 if (!(i % copies)) 427 rebuilds_per_group = 0; 428 d = i % rs->md.raid_disks; 429 if ((!rs->dev[d].rdev.sb_page || 430 !test_bit(In_sync, &rs->dev[d].rdev.flags)) && 431 (++rebuilds_per_group >= copies)) 432 goto too_many; 433 } 434 break; 435 } 436 437 /* 438 * When checking "far" and "offset" formats, we need to ensure 439 * that the device that holds its copy is not also dead or 440 * being rebuilt. (Note that "far" and "offset" formats only 441 * support two copies right now. These formats also only ever 442 * use the 'use_far_sets' variant.) 443 * 444 * This check is somewhat complicated by the need to account 445 * for arrays that are not a multiple of (far) copies. This 446 * results in the need to treat the last (potentially larger) 447 * set differently. 448 */ 449 group_size = (rs->md.raid_disks / copies); 450 last_group_start = (rs->md.raid_disks / group_size) - 1; 451 last_group_start *= group_size; 452 for (i = 0; i < rs->md.raid_disks; i++) { 453 if (!(i % copies) && !(i > last_group_start)) 454 rebuilds_per_group = 0; 455 if ((!rs->dev[i].rdev.sb_page || 456 !test_bit(In_sync, &rs->dev[i].rdev.flags)) && 457 (++rebuilds_per_group >= copies)) 458 goto too_many; 459 } 460 break; 461 default: 462 if (rebuild_cnt) 463 return -EINVAL; 464 } 465 466 return 0; 467 468 too_many: 469 return -EINVAL; 470 } 471 472 /* 473 * Possible arguments are... 474 * <chunk_size> [optional_args] 475 * 476 * Argument definitions 477 * <chunk_size> The number of sectors per disk that 478 * will form the "stripe" 479 * [[no]sync] Force or prevent recovery of the 480 * entire array 481 * [rebuild <idx>] Rebuild the drive indicated by the index 482 * [daemon_sleep <ms>] Time between bitmap daemon work to 483 * clear bits 484 * [min_recovery_rate <kB/sec/disk>] Throttle RAID initialization 485 * [max_recovery_rate <kB/sec/disk>] Throttle RAID initialization 486 * [write_mostly <idx>] Indicate a write mostly drive via index 487 * [max_write_behind <sectors>] See '-write-behind=' (man mdadm) 488 * [stripe_cache <sectors>] Stripe cache size for higher RAIDs 489 * [region_size <sectors>] Defines granularity of bitmap 490 * 491 * RAID10-only options: 492 * [raid10_copies <# copies>] Number of copies. (Default: 2) 493 * [raid10_format <near|far|offset>] Layout algorithm. (Default: near) 494 */ 495 static int parse_raid_params(struct raid_set *rs, char **argv, 496 unsigned num_raid_params) 497 { 498 char *raid10_format = "near"; 499 unsigned raid10_copies = 2; 500 unsigned i; 501 unsigned long value, region_size = 0; 502 sector_t sectors_per_dev = rs->ti->len; 503 sector_t max_io_len; 504 char *key; 505 506 /* 507 * First, parse the in-order required arguments 508 * "chunk_size" is the only argument of this type. 509 */ 510 if ((kstrtoul(argv[0], 10, &value) < 0)) { 511 rs->ti->error = "Bad chunk size"; 512 return -EINVAL; 513 } else if (rs->raid_type->level == 1) { 514 if (value) 515 DMERR("Ignoring chunk size parameter for RAID 1"); 516 value = 0; 517 } else if (!is_power_of_2(value)) { 518 rs->ti->error = "Chunk size must be a power of 2"; 519 return -EINVAL; 520 } else if (value < 8) { 521 rs->ti->error = "Chunk size value is too small"; 522 return -EINVAL; 523 } 524 525 rs->md.new_chunk_sectors = rs->md.chunk_sectors = value; 526 argv++; 527 num_raid_params--; 528 529 /* 530 * We set each individual device as In_sync with a completed 531 * 'recovery_offset'. If there has been a device failure or 532 * replacement then one of the following cases applies: 533 * 534 * 1) User specifies 'rebuild'. 535 * - Device is reset when param is read. 536 * 2) A new device is supplied. 537 * - No matching superblock found, resets device. 538 * 3) Device failure was transient and returns on reload. 539 * - Failure noticed, resets device for bitmap replay. 540 * 4) Device hadn't completed recovery after previous failure. 541 * - Superblock is read and overrides recovery_offset. 542 * 543 * What is found in the superblocks of the devices is always 544 * authoritative, unless 'rebuild' or '[no]sync' was specified. 545 */ 546 for (i = 0; i < rs->md.raid_disks; i++) { 547 set_bit(In_sync, &rs->dev[i].rdev.flags); 548 rs->dev[i].rdev.recovery_offset = MaxSector; 549 } 550 551 /* 552 * Second, parse the unordered optional arguments 553 */ 554 for (i = 0; i < num_raid_params; i++) { 555 if (!strcasecmp(argv[i], "nosync")) { 556 rs->md.recovery_cp = MaxSector; 557 rs->ctr_flags |= CTR_FLAG_NOSYNC; 558 continue; 559 } 560 if (!strcasecmp(argv[i], "sync")) { 561 rs->md.recovery_cp = 0; 562 rs->ctr_flags |= CTR_FLAG_SYNC; 563 continue; 564 } 565 566 /* The rest of the optional arguments come in key/value pairs */ 567 if ((i + 1) >= num_raid_params) { 568 rs->ti->error = "Wrong number of raid parameters given"; 569 return -EINVAL; 570 } 571 572 key = argv[i++]; 573 574 /* Parameters that take a string value are checked here. */ 575 if (!strcasecmp(key, "raid10_format")) { 576 if (rs->raid_type->level != 10) { 577 rs->ti->error = "'raid10_format' is an invalid parameter for this RAID type"; 578 return -EINVAL; 579 } 580 if (strcmp("near", argv[i]) && 581 strcmp("far", argv[i]) && 582 strcmp("offset", argv[i])) { 583 rs->ti->error = "Invalid 'raid10_format' value given"; 584 return -EINVAL; 585 } 586 raid10_format = argv[i]; 587 rs->ctr_flags |= CTR_FLAG_RAID10_FORMAT; 588 continue; 589 } 590 591 if (kstrtoul(argv[i], 10, &value) < 0) { 592 rs->ti->error = "Bad numerical argument given in raid params"; 593 return -EINVAL; 594 } 595 596 /* Parameters that take a numeric value are checked here */ 597 if (!strcasecmp(key, "rebuild")) { 598 if (value >= rs->md.raid_disks) { 599 rs->ti->error = "Invalid rebuild index given"; 600 return -EINVAL; 601 } 602 clear_bit(In_sync, &rs->dev[value].rdev.flags); 603 rs->dev[value].rdev.recovery_offset = 0; 604 rs->ctr_flags |= CTR_FLAG_REBUILD; 605 } else if (!strcasecmp(key, "write_mostly")) { 606 if (rs->raid_type->level != 1) { 607 rs->ti->error = "write_mostly option is only valid for RAID1"; 608 return -EINVAL; 609 } 610 if (value >= rs->md.raid_disks) { 611 rs->ti->error = "Invalid write_mostly drive index given"; 612 return -EINVAL; 613 } 614 set_bit(WriteMostly, &rs->dev[value].rdev.flags); 615 } else if (!strcasecmp(key, "max_write_behind")) { 616 if (rs->raid_type->level != 1) { 617 rs->ti->error = "max_write_behind option is only valid for RAID1"; 618 return -EINVAL; 619 } 620 rs->ctr_flags |= CTR_FLAG_MAX_WRITE_BEHIND; 621 622 /* 623 * In device-mapper, we specify things in sectors, but 624 * MD records this value in kB 625 */ 626 value /= 2; 627 if (value > COUNTER_MAX) { 628 rs->ti->error = "Max write-behind limit out of range"; 629 return -EINVAL; 630 } 631 rs->md.bitmap_info.max_write_behind = value; 632 } else if (!strcasecmp(key, "daemon_sleep")) { 633 rs->ctr_flags |= CTR_FLAG_DAEMON_SLEEP; 634 if (!value || (value > MAX_SCHEDULE_TIMEOUT)) { 635 rs->ti->error = "daemon sleep period out of range"; 636 return -EINVAL; 637 } 638 rs->md.bitmap_info.daemon_sleep = value; 639 } else if (!strcasecmp(key, "stripe_cache")) { 640 rs->ctr_flags |= CTR_FLAG_STRIPE_CACHE; 641 642 /* 643 * In device-mapper, we specify things in sectors, but 644 * MD records this value in kB 645 */ 646 value /= 2; 647 648 if ((rs->raid_type->level != 5) && 649 (rs->raid_type->level != 6)) { 650 rs->ti->error = "Inappropriate argument: stripe_cache"; 651 return -EINVAL; 652 } 653 if (raid5_set_cache_size(&rs->md, (int)value)) { 654 rs->ti->error = "Bad stripe_cache size"; 655 return -EINVAL; 656 } 657 } else if (!strcasecmp(key, "min_recovery_rate")) { 658 rs->ctr_flags |= CTR_FLAG_MIN_RECOVERY_RATE; 659 if (value > INT_MAX) { 660 rs->ti->error = "min_recovery_rate out of range"; 661 return -EINVAL; 662 } 663 rs->md.sync_speed_min = (int)value; 664 } else if (!strcasecmp(key, "max_recovery_rate")) { 665 rs->ctr_flags |= CTR_FLAG_MAX_RECOVERY_RATE; 666 if (value > INT_MAX) { 667 rs->ti->error = "max_recovery_rate out of range"; 668 return -EINVAL; 669 } 670 rs->md.sync_speed_max = (int)value; 671 } else if (!strcasecmp(key, "region_size")) { 672 rs->ctr_flags |= CTR_FLAG_REGION_SIZE; 673 region_size = value; 674 } else if (!strcasecmp(key, "raid10_copies") && 675 (rs->raid_type->level == 10)) { 676 if ((value < 2) || (value > 0xFF)) { 677 rs->ti->error = "Bad value for 'raid10_copies'"; 678 return -EINVAL; 679 } 680 rs->ctr_flags |= CTR_FLAG_RAID10_COPIES; 681 raid10_copies = value; 682 } else { 683 DMERR("Unable to parse RAID parameter: %s", key); 684 rs->ti->error = "Unable to parse RAID parameters"; 685 return -EINVAL; 686 } 687 } 688 689 if (validate_region_size(rs, region_size)) 690 return -EINVAL; 691 692 if (rs->md.chunk_sectors) 693 max_io_len = rs->md.chunk_sectors; 694 else 695 max_io_len = region_size; 696 697 if (dm_set_target_max_io_len(rs->ti, max_io_len)) 698 return -EINVAL; 699 700 if (rs->raid_type->level == 10) { 701 if (raid10_copies > rs->md.raid_disks) { 702 rs->ti->error = "Not enough devices to satisfy specification"; 703 return -EINVAL; 704 } 705 706 /* 707 * If the format is not "near", we only support 708 * two copies at the moment. 709 */ 710 if (strcmp("near", raid10_format) && (raid10_copies > 2)) { 711 rs->ti->error = "Too many copies for given RAID10 format."; 712 return -EINVAL; 713 } 714 715 /* (Len * #mirrors) / #devices */ 716 sectors_per_dev = rs->ti->len * raid10_copies; 717 sector_div(sectors_per_dev, rs->md.raid_disks); 718 719 rs->md.layout = raid10_format_to_md_layout(raid10_format, 720 raid10_copies); 721 rs->md.new_layout = rs->md.layout; 722 } else if ((!rs->raid_type->level || rs->raid_type->level > 1) && 723 sector_div(sectors_per_dev, 724 (rs->md.raid_disks - rs->raid_type->parity_devs))) { 725 rs->ti->error = "Target length not divisible by number of data devices"; 726 return -EINVAL; 727 } 728 rs->md.dev_sectors = sectors_per_dev; 729 730 /* Assume there are no metadata devices until the drives are parsed */ 731 rs->md.persistent = 0; 732 rs->md.external = 1; 733 734 return 0; 735 } 736 737 static void do_table_event(struct work_struct *ws) 738 { 739 struct raid_set *rs = container_of(ws, struct raid_set, md.event_work); 740 741 dm_table_event(rs->ti->table); 742 } 743 744 static int raid_is_congested(struct dm_target_callbacks *cb, int bits) 745 { 746 struct raid_set *rs = container_of(cb, struct raid_set, callbacks); 747 748 return mddev_congested(&rs->md, bits); 749 } 750 751 /* 752 * This structure is never routinely used by userspace, unlike md superblocks. 753 * Devices with this superblock should only ever be accessed via device-mapper. 754 */ 755 #define DM_RAID_MAGIC 0x64526D44 756 struct dm_raid_superblock { 757 __le32 magic; /* "DmRd" */ 758 __le32 features; /* Used to indicate possible future changes */ 759 760 __le32 num_devices; /* Number of devices in this array. (Max 64) */ 761 __le32 array_position; /* The position of this drive in the array */ 762 763 __le64 events; /* Incremented by md when superblock updated */ 764 __le64 failed_devices; /* Bit field of devices to indicate failures */ 765 766 /* 767 * This offset tracks the progress of the repair or replacement of 768 * an individual drive. 769 */ 770 __le64 disk_recovery_offset; 771 772 /* 773 * This offset tracks the progress of the initial array 774 * synchronisation/parity calculation. 775 */ 776 __le64 array_resync_offset; 777 778 /* 779 * RAID characteristics 780 */ 781 __le32 level; 782 __le32 layout; 783 __le32 stripe_sectors; 784 785 /* Remainder of a logical block is zero-filled when writing (see super_sync()). */ 786 } __packed; 787 788 static int read_disk_sb(struct md_rdev *rdev, int size) 789 { 790 BUG_ON(!rdev->sb_page); 791 792 if (rdev->sb_loaded) 793 return 0; 794 795 if (!sync_page_io(rdev, 0, size, rdev->sb_page, READ, 1)) { 796 DMERR("Failed to read superblock of device at position %d", 797 rdev->raid_disk); 798 md_error(rdev->mddev, rdev); 799 return -EINVAL; 800 } 801 802 rdev->sb_loaded = 1; 803 804 return 0; 805 } 806 807 static void super_sync(struct mddev *mddev, struct md_rdev *rdev) 808 { 809 int i; 810 uint64_t failed_devices; 811 struct dm_raid_superblock *sb; 812 struct raid_set *rs = container_of(mddev, struct raid_set, md); 813 814 sb = page_address(rdev->sb_page); 815 failed_devices = le64_to_cpu(sb->failed_devices); 816 817 for (i = 0; i < mddev->raid_disks; i++) 818 if (!rs->dev[i].data_dev || 819 test_bit(Faulty, &(rs->dev[i].rdev.flags))) 820 failed_devices |= (1ULL << i); 821 822 memset(sb + 1, 0, rdev->sb_size - sizeof(*sb)); 823 824 sb->magic = cpu_to_le32(DM_RAID_MAGIC); 825 sb->features = cpu_to_le32(0); /* No features yet */ 826 827 sb->num_devices = cpu_to_le32(mddev->raid_disks); 828 sb->array_position = cpu_to_le32(rdev->raid_disk); 829 830 sb->events = cpu_to_le64(mddev->events); 831 sb->failed_devices = cpu_to_le64(failed_devices); 832 833 sb->disk_recovery_offset = cpu_to_le64(rdev->recovery_offset); 834 sb->array_resync_offset = cpu_to_le64(mddev->recovery_cp); 835 836 sb->level = cpu_to_le32(mddev->level); 837 sb->layout = cpu_to_le32(mddev->layout); 838 sb->stripe_sectors = cpu_to_le32(mddev->chunk_sectors); 839 } 840 841 /* 842 * super_load 843 * 844 * This function creates a superblock if one is not found on the device 845 * and will decide which superblock to use if there's a choice. 846 * 847 * Return: 1 if use rdev, 0 if use refdev, -Exxx otherwise 848 */ 849 static int super_load(struct md_rdev *rdev, struct md_rdev *refdev) 850 { 851 int ret; 852 struct dm_raid_superblock *sb; 853 struct dm_raid_superblock *refsb; 854 uint64_t events_sb, events_refsb; 855 856 rdev->sb_start = 0; 857 rdev->sb_size = bdev_logical_block_size(rdev->meta_bdev); 858 if (rdev->sb_size < sizeof(*sb) || rdev->sb_size > PAGE_SIZE) { 859 DMERR("superblock size of a logical block is no longer valid"); 860 return -EINVAL; 861 } 862 863 ret = read_disk_sb(rdev, rdev->sb_size); 864 if (ret) 865 return ret; 866 867 sb = page_address(rdev->sb_page); 868 869 /* 870 * Two cases that we want to write new superblocks and rebuild: 871 * 1) New device (no matching magic number) 872 * 2) Device specified for rebuild (!In_sync w/ offset == 0) 873 */ 874 if ((sb->magic != cpu_to_le32(DM_RAID_MAGIC)) || 875 (!test_bit(In_sync, &rdev->flags) && !rdev->recovery_offset)) { 876 super_sync(rdev->mddev, rdev); 877 878 set_bit(FirstUse, &rdev->flags); 879 880 /* Force writing of superblocks to disk */ 881 set_bit(MD_CHANGE_DEVS, &rdev->mddev->flags); 882 883 /* Any superblock is better than none, choose that if given */ 884 return refdev ? 0 : 1; 885 } 886 887 if (!refdev) 888 return 1; 889 890 events_sb = le64_to_cpu(sb->events); 891 892 refsb = page_address(refdev->sb_page); 893 events_refsb = le64_to_cpu(refsb->events); 894 895 return (events_sb > events_refsb) ? 1 : 0; 896 } 897 898 static int super_init_validation(struct mddev *mddev, struct md_rdev *rdev) 899 { 900 int role; 901 struct raid_set *rs = container_of(mddev, struct raid_set, md); 902 uint64_t events_sb; 903 uint64_t failed_devices; 904 struct dm_raid_superblock *sb; 905 uint32_t new_devs = 0; 906 uint32_t rebuilds = 0; 907 struct md_rdev *r; 908 struct dm_raid_superblock *sb2; 909 910 sb = page_address(rdev->sb_page); 911 events_sb = le64_to_cpu(sb->events); 912 failed_devices = le64_to_cpu(sb->failed_devices); 913 914 /* 915 * Initialise to 1 if this is a new superblock. 916 */ 917 mddev->events = events_sb ? : 1; 918 919 /* 920 * Reshaping is not currently allowed 921 */ 922 if (le32_to_cpu(sb->level) != mddev->level) { 923 DMERR("Reshaping arrays not yet supported. (RAID level change)"); 924 return -EINVAL; 925 } 926 if (le32_to_cpu(sb->layout) != mddev->layout) { 927 DMERR("Reshaping arrays not yet supported. (RAID layout change)"); 928 DMERR(" 0x%X vs 0x%X", le32_to_cpu(sb->layout), mddev->layout); 929 DMERR(" Old layout: %s w/ %d copies", 930 raid10_md_layout_to_format(le32_to_cpu(sb->layout)), 931 raid10_md_layout_to_copies(le32_to_cpu(sb->layout))); 932 DMERR(" New layout: %s w/ %d copies", 933 raid10_md_layout_to_format(mddev->layout), 934 raid10_md_layout_to_copies(mddev->layout)); 935 return -EINVAL; 936 } 937 if (le32_to_cpu(sb->stripe_sectors) != mddev->chunk_sectors) { 938 DMERR("Reshaping arrays not yet supported. (stripe sectors change)"); 939 return -EINVAL; 940 } 941 942 /* We can only change the number of devices in RAID1 right now */ 943 if ((rs->raid_type->level != 1) && 944 (le32_to_cpu(sb->num_devices) != mddev->raid_disks)) { 945 DMERR("Reshaping arrays not yet supported. (device count change)"); 946 return -EINVAL; 947 } 948 949 if (!(rs->ctr_flags & (CTR_FLAG_SYNC | CTR_FLAG_NOSYNC))) 950 mddev->recovery_cp = le64_to_cpu(sb->array_resync_offset); 951 952 /* 953 * During load, we set FirstUse if a new superblock was written. 954 * There are two reasons we might not have a superblock: 955 * 1) The array is brand new - in which case, all of the 956 * devices must have their In_sync bit set. Also, 957 * recovery_cp must be 0, unless forced. 958 * 2) This is a new device being added to an old array 959 * and the new device needs to be rebuilt - in which 960 * case the In_sync bit will /not/ be set and 961 * recovery_cp must be MaxSector. 962 */ 963 rdev_for_each(r, mddev) { 964 if (!test_bit(In_sync, &r->flags)) { 965 DMINFO("Device %d specified for rebuild: " 966 "Clearing superblock", r->raid_disk); 967 rebuilds++; 968 } else if (test_bit(FirstUse, &r->flags)) 969 new_devs++; 970 } 971 972 if (!rebuilds) { 973 if (new_devs == mddev->raid_disks) { 974 DMINFO("Superblocks created for new array"); 975 set_bit(MD_ARRAY_FIRST_USE, &mddev->flags); 976 } else if (new_devs) { 977 DMERR("New device injected " 978 "into existing array without 'rebuild' " 979 "parameter specified"); 980 return -EINVAL; 981 } 982 } else if (new_devs) { 983 DMERR("'rebuild' devices cannot be " 984 "injected into an array with other first-time devices"); 985 return -EINVAL; 986 } else if (mddev->recovery_cp != MaxSector) { 987 DMERR("'rebuild' specified while array is not in-sync"); 988 return -EINVAL; 989 } 990 991 /* 992 * Now we set the Faulty bit for those devices that are 993 * recorded in the superblock as failed. 994 */ 995 rdev_for_each(r, mddev) { 996 if (!r->sb_page) 997 continue; 998 sb2 = page_address(r->sb_page); 999 sb2->failed_devices = 0; 1000 1001 /* 1002 * Check for any device re-ordering. 1003 */ 1004 if (!test_bit(FirstUse, &r->flags) && (r->raid_disk >= 0)) { 1005 role = le32_to_cpu(sb2->array_position); 1006 if (role != r->raid_disk) { 1007 if (rs->raid_type->level != 1) { 1008 rs->ti->error = "Cannot change device " 1009 "positions in RAID array"; 1010 return -EINVAL; 1011 } 1012 DMINFO("RAID1 device #%d now at position #%d", 1013 role, r->raid_disk); 1014 } 1015 1016 /* 1017 * Partial recovery is performed on 1018 * returning failed devices. 1019 */ 1020 if (failed_devices & (1 << role)) 1021 set_bit(Faulty, &r->flags); 1022 } 1023 } 1024 1025 return 0; 1026 } 1027 1028 static int super_validate(struct raid_set *rs, struct md_rdev *rdev) 1029 { 1030 struct mddev *mddev = &rs->md; 1031 struct dm_raid_superblock *sb = page_address(rdev->sb_page); 1032 1033 /* 1034 * If mddev->events is not set, we know we have not yet initialized 1035 * the array. 1036 */ 1037 if (!mddev->events && super_init_validation(mddev, rdev)) 1038 return -EINVAL; 1039 1040 if (le32_to_cpu(sb->features)) { 1041 rs->ti->error = "Unable to assemble array: No feature flags supported yet"; 1042 return -EINVAL; 1043 } 1044 1045 /* Enable bitmap creation for RAID levels != 0 */ 1046 mddev->bitmap_info.offset = (rs->raid_type->level) ? to_sector(4096) : 0; 1047 rdev->mddev->bitmap_info.default_offset = mddev->bitmap_info.offset; 1048 1049 if (!test_bit(FirstUse, &rdev->flags)) { 1050 rdev->recovery_offset = le64_to_cpu(sb->disk_recovery_offset); 1051 if (rdev->recovery_offset != MaxSector) 1052 clear_bit(In_sync, &rdev->flags); 1053 } 1054 1055 /* 1056 * If a device comes back, set it as not In_sync and no longer faulty. 1057 */ 1058 if (test_bit(Faulty, &rdev->flags)) { 1059 clear_bit(Faulty, &rdev->flags); 1060 clear_bit(In_sync, &rdev->flags); 1061 rdev->saved_raid_disk = rdev->raid_disk; 1062 rdev->recovery_offset = 0; 1063 } 1064 1065 clear_bit(FirstUse, &rdev->flags); 1066 1067 return 0; 1068 } 1069 1070 /* 1071 * Analyse superblocks and select the freshest. 1072 */ 1073 static int analyse_superblocks(struct dm_target *ti, struct raid_set *rs) 1074 { 1075 int ret; 1076 struct raid_dev *dev; 1077 struct md_rdev *rdev, *tmp, *freshest; 1078 struct mddev *mddev = &rs->md; 1079 1080 freshest = NULL; 1081 rdev_for_each_safe(rdev, tmp, mddev) { 1082 /* 1083 * Skipping super_load due to CTR_FLAG_SYNC will cause 1084 * the array to undergo initialization again as 1085 * though it were new. This is the intended effect 1086 * of the "sync" directive. 1087 * 1088 * When reshaping capability is added, we must ensure 1089 * that the "sync" directive is disallowed during the 1090 * reshape. 1091 */ 1092 rdev->sectors = to_sector(i_size_read(rdev->bdev->bd_inode)); 1093 1094 if (rs->ctr_flags & CTR_FLAG_SYNC) 1095 continue; 1096 1097 if (!rdev->meta_bdev) 1098 continue; 1099 1100 ret = super_load(rdev, freshest); 1101 1102 switch (ret) { 1103 case 1: 1104 freshest = rdev; 1105 break; 1106 case 0: 1107 break; 1108 default: 1109 dev = container_of(rdev, struct raid_dev, rdev); 1110 if (dev->meta_dev) 1111 dm_put_device(ti, dev->meta_dev); 1112 1113 dev->meta_dev = NULL; 1114 rdev->meta_bdev = NULL; 1115 1116 if (rdev->sb_page) 1117 put_page(rdev->sb_page); 1118 1119 rdev->sb_page = NULL; 1120 1121 rdev->sb_loaded = 0; 1122 1123 /* 1124 * We might be able to salvage the data device 1125 * even though the meta device has failed. For 1126 * now, we behave as though '- -' had been 1127 * set for this device in the table. 1128 */ 1129 if (dev->data_dev) 1130 dm_put_device(ti, dev->data_dev); 1131 1132 dev->data_dev = NULL; 1133 rdev->bdev = NULL; 1134 1135 list_del(&rdev->same_set); 1136 } 1137 } 1138 1139 if (!freshest) 1140 return 0; 1141 1142 if (validate_raid_redundancy(rs)) { 1143 rs->ti->error = "Insufficient redundancy to activate array"; 1144 return -EINVAL; 1145 } 1146 1147 /* 1148 * Validation of the freshest device provides the source of 1149 * validation for the remaining devices. 1150 */ 1151 ti->error = "Unable to assemble array: Invalid superblocks"; 1152 if (super_validate(rs, freshest)) 1153 return -EINVAL; 1154 1155 rdev_for_each(rdev, mddev) 1156 if ((rdev != freshest) && super_validate(rs, rdev)) 1157 return -EINVAL; 1158 1159 return 0; 1160 } 1161 1162 /* 1163 * Enable/disable discard support on RAID set depending on 1164 * RAID level and discard properties of underlying RAID members. 1165 */ 1166 static void configure_discard_support(struct dm_target *ti, struct raid_set *rs) 1167 { 1168 int i; 1169 bool raid456; 1170 1171 /* Assume discards not supported until after checks below. */ 1172 ti->discards_supported = false; 1173 1174 /* RAID level 4,5,6 require discard_zeroes_data for data integrity! */ 1175 raid456 = (rs->md.level == 4 || rs->md.level == 5 || rs->md.level == 6); 1176 1177 for (i = 0; i < rs->md.raid_disks; i++) { 1178 struct request_queue *q; 1179 1180 if (!rs->dev[i].rdev.bdev) 1181 continue; 1182 1183 q = bdev_get_queue(rs->dev[i].rdev.bdev); 1184 if (!q || !blk_queue_discard(q)) 1185 return; 1186 1187 if (raid456) { 1188 if (!q->limits.discard_zeroes_data) 1189 return; 1190 if (!devices_handle_discard_safely) { 1191 DMERR("raid456 discard support disabled due to discard_zeroes_data uncertainty."); 1192 DMERR("Set dm-raid.devices_handle_discard_safely=Y to override."); 1193 return; 1194 } 1195 } 1196 } 1197 1198 /* All RAID members properly support discards */ 1199 ti->discards_supported = true; 1200 1201 /* 1202 * RAID1 and RAID10 personalities require bio splitting, 1203 * RAID0/4/5/6 don't and process large discard bios properly. 1204 */ 1205 ti->split_discard_bios = !!(rs->md.level == 1 || rs->md.level == 10); 1206 ti->num_discard_bios = 1; 1207 } 1208 1209 /* 1210 * Construct a RAID4/5/6 mapping: 1211 * Args: 1212 * <raid_type> <#raid_params> <raid_params> \ 1213 * <#raid_devs> { <meta_dev1> <dev1> .. <meta_devN> <devN> } 1214 * 1215 * <raid_params> varies by <raid_type>. See 'parse_raid_params' for 1216 * details on possible <raid_params>. 1217 */ 1218 static int raid_ctr(struct dm_target *ti, unsigned argc, char **argv) 1219 { 1220 int ret; 1221 struct raid_type *rt; 1222 unsigned long num_raid_params, num_raid_devs; 1223 struct raid_set *rs = NULL; 1224 1225 /* Must have at least <raid_type> <#raid_params> */ 1226 if (argc < 2) { 1227 ti->error = "Too few arguments"; 1228 return -EINVAL; 1229 } 1230 1231 /* raid type */ 1232 rt = get_raid_type(argv[0]); 1233 if (!rt) { 1234 ti->error = "Unrecognised raid_type"; 1235 return -EINVAL; 1236 } 1237 argc--; 1238 argv++; 1239 1240 /* number of RAID parameters */ 1241 if (kstrtoul(argv[0], 10, &num_raid_params) < 0) { 1242 ti->error = "Cannot understand number of RAID parameters"; 1243 return -EINVAL; 1244 } 1245 argc--; 1246 argv++; 1247 1248 /* Skip over RAID params for now and find out # of devices */ 1249 if (num_raid_params >= argc) { 1250 ti->error = "Arguments do not agree with counts given"; 1251 return -EINVAL; 1252 } 1253 1254 if ((kstrtoul(argv[num_raid_params], 10, &num_raid_devs) < 0) || 1255 (num_raid_devs > MAX_RAID_DEVICES)) { 1256 ti->error = "Cannot understand number of raid devices"; 1257 return -EINVAL; 1258 } 1259 1260 argc -= num_raid_params + 1; /* +1: we already have num_raid_devs */ 1261 if (argc != (num_raid_devs * 2)) { 1262 ti->error = "Supplied RAID devices does not match the count given"; 1263 return -EINVAL; 1264 } 1265 1266 rs = context_alloc(ti, rt, (unsigned)num_raid_devs); 1267 if (IS_ERR(rs)) 1268 return PTR_ERR(rs); 1269 1270 ret = parse_raid_params(rs, argv, (unsigned)num_raid_params); 1271 if (ret) 1272 goto bad; 1273 1274 argv += num_raid_params + 1; 1275 1276 ret = dev_parms(rs, argv); 1277 if (ret) 1278 goto bad; 1279 1280 rs->md.sync_super = super_sync; 1281 ret = analyse_superblocks(ti, rs); 1282 if (ret) 1283 goto bad; 1284 1285 INIT_WORK(&rs->md.event_work, do_table_event); 1286 ti->private = rs; 1287 ti->num_flush_bios = 1; 1288 1289 /* 1290 * Disable/enable discard support on RAID set. 1291 */ 1292 configure_discard_support(ti, rs); 1293 1294 /* Has to be held on running the array */ 1295 mddev_lock_nointr(&rs->md); 1296 ret = md_run(&rs->md); 1297 rs->md.in_sync = 0; /* Assume already marked dirty */ 1298 mddev_unlock(&rs->md); 1299 1300 if (ret) { 1301 ti->error = "Fail to run raid array"; 1302 goto bad; 1303 } 1304 1305 if (ti->len != rs->md.array_sectors) { 1306 ti->error = "Array size does not match requested target length"; 1307 ret = -EINVAL; 1308 goto size_mismatch; 1309 } 1310 rs->callbacks.congested_fn = raid_is_congested; 1311 dm_table_add_target_callbacks(ti->table, &rs->callbacks); 1312 1313 mddev_suspend(&rs->md); 1314 return 0; 1315 1316 size_mismatch: 1317 md_stop(&rs->md); 1318 bad: 1319 context_free(rs); 1320 1321 return ret; 1322 } 1323 1324 static void raid_dtr(struct dm_target *ti) 1325 { 1326 struct raid_set *rs = ti->private; 1327 1328 list_del_init(&rs->callbacks.list); 1329 md_stop(&rs->md); 1330 context_free(rs); 1331 } 1332 1333 static int raid_map(struct dm_target *ti, struct bio *bio) 1334 { 1335 struct raid_set *rs = ti->private; 1336 struct mddev *mddev = &rs->md; 1337 1338 mddev->pers->make_request(mddev, bio); 1339 1340 return DM_MAPIO_SUBMITTED; 1341 } 1342 1343 static const char *decipher_sync_action(struct mddev *mddev) 1344 { 1345 if (test_bit(MD_RECOVERY_FROZEN, &mddev->recovery)) 1346 return "frozen"; 1347 1348 if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) || 1349 (!mddev->ro && test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))) { 1350 if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)) 1351 return "reshape"; 1352 1353 if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) { 1354 if (!test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) 1355 return "resync"; 1356 else if (test_bit(MD_RECOVERY_CHECK, &mddev->recovery)) 1357 return "check"; 1358 return "repair"; 1359 } 1360 1361 if (test_bit(MD_RECOVERY_RECOVER, &mddev->recovery)) 1362 return "recover"; 1363 } 1364 1365 return "idle"; 1366 } 1367 1368 static void raid_status(struct dm_target *ti, status_type_t type, 1369 unsigned status_flags, char *result, unsigned maxlen) 1370 { 1371 struct raid_set *rs = ti->private; 1372 unsigned raid_param_cnt = 1; /* at least 1 for chunksize */ 1373 unsigned sz = 0; 1374 int i, array_in_sync = 0; 1375 sector_t sync; 1376 1377 switch (type) { 1378 case STATUSTYPE_INFO: 1379 DMEMIT("%s %d ", rs->raid_type->name, rs->md.raid_disks); 1380 1381 if (rs->raid_type->level) { 1382 if (test_bit(MD_RECOVERY_RUNNING, &rs->md.recovery)) 1383 sync = rs->md.curr_resync_completed; 1384 else 1385 sync = rs->md.recovery_cp; 1386 1387 if (sync >= rs->md.resync_max_sectors) { 1388 /* 1389 * Sync complete. 1390 */ 1391 array_in_sync = 1; 1392 sync = rs->md.resync_max_sectors; 1393 } else if (test_bit(MD_RECOVERY_REQUESTED, &rs->md.recovery)) { 1394 /* 1395 * If "check" or "repair" is occurring, the array has 1396 * undergone and initial sync and the health characters 1397 * should not be 'a' anymore. 1398 */ 1399 array_in_sync = 1; 1400 } else { 1401 /* 1402 * The array may be doing an initial sync, or it may 1403 * be rebuilding individual components. If all the 1404 * devices are In_sync, then it is the array that is 1405 * being initialized. 1406 */ 1407 for (i = 0; i < rs->md.raid_disks; i++) 1408 if (!test_bit(In_sync, &rs->dev[i].rdev.flags)) 1409 array_in_sync = 1; 1410 } 1411 } else { 1412 /* RAID0 */ 1413 array_in_sync = 1; 1414 sync = rs->md.resync_max_sectors; 1415 } 1416 1417 /* 1418 * Status characters: 1419 * 'D' = Dead/Failed device 1420 * 'a' = Alive but not in-sync 1421 * 'A' = Alive and in-sync 1422 */ 1423 for (i = 0; i < rs->md.raid_disks; i++) { 1424 if (test_bit(Faulty, &rs->dev[i].rdev.flags)) 1425 DMEMIT("D"); 1426 else if (!array_in_sync || 1427 !test_bit(In_sync, &rs->dev[i].rdev.flags)) 1428 DMEMIT("a"); 1429 else 1430 DMEMIT("A"); 1431 } 1432 1433 /* 1434 * In-sync ratio: 1435 * The in-sync ratio shows the progress of: 1436 * - Initializing the array 1437 * - Rebuilding a subset of devices of the array 1438 * The user can distinguish between the two by referring 1439 * to the status characters. 1440 */ 1441 DMEMIT(" %llu/%llu", 1442 (unsigned long long) sync, 1443 (unsigned long long) rs->md.resync_max_sectors); 1444 1445 /* 1446 * Sync action: 1447 * See Documentation/device-mapper/dm-raid.c for 1448 * information on each of these states. 1449 */ 1450 DMEMIT(" %s", decipher_sync_action(&rs->md)); 1451 1452 /* 1453 * resync_mismatches/mismatch_cnt 1454 * This field shows the number of discrepancies found when 1455 * performing a "check" of the array. 1456 */ 1457 DMEMIT(" %llu", 1458 (strcmp(rs->md.last_sync_action, "check")) ? 0 : 1459 (unsigned long long) 1460 atomic64_read(&rs->md.resync_mismatches)); 1461 break; 1462 case STATUSTYPE_TABLE: 1463 /* The string you would use to construct this array */ 1464 for (i = 0; i < rs->md.raid_disks; i++) { 1465 if ((rs->ctr_flags & CTR_FLAG_REBUILD) && 1466 rs->dev[i].data_dev && 1467 !test_bit(In_sync, &rs->dev[i].rdev.flags)) 1468 raid_param_cnt += 2; /* for rebuilds */ 1469 if (rs->dev[i].data_dev && 1470 test_bit(WriteMostly, &rs->dev[i].rdev.flags)) 1471 raid_param_cnt += 2; 1472 } 1473 1474 raid_param_cnt += (hweight32(rs->ctr_flags & ~CTR_FLAG_REBUILD) * 2); 1475 if (rs->ctr_flags & (CTR_FLAG_SYNC | CTR_FLAG_NOSYNC)) 1476 raid_param_cnt--; 1477 1478 DMEMIT("%s %u %u", rs->raid_type->name, 1479 raid_param_cnt, rs->md.chunk_sectors); 1480 1481 if ((rs->ctr_flags & CTR_FLAG_SYNC) && 1482 (rs->md.recovery_cp == MaxSector)) 1483 DMEMIT(" sync"); 1484 if (rs->ctr_flags & CTR_FLAG_NOSYNC) 1485 DMEMIT(" nosync"); 1486 1487 for (i = 0; i < rs->md.raid_disks; i++) 1488 if ((rs->ctr_flags & CTR_FLAG_REBUILD) && 1489 rs->dev[i].data_dev && 1490 !test_bit(In_sync, &rs->dev[i].rdev.flags)) 1491 DMEMIT(" rebuild %u", i); 1492 1493 if (rs->ctr_flags & CTR_FLAG_DAEMON_SLEEP) 1494 DMEMIT(" daemon_sleep %lu", 1495 rs->md.bitmap_info.daemon_sleep); 1496 1497 if (rs->ctr_flags & CTR_FLAG_MIN_RECOVERY_RATE) 1498 DMEMIT(" min_recovery_rate %d", rs->md.sync_speed_min); 1499 1500 if (rs->ctr_flags & CTR_FLAG_MAX_RECOVERY_RATE) 1501 DMEMIT(" max_recovery_rate %d", rs->md.sync_speed_max); 1502 1503 for (i = 0; i < rs->md.raid_disks; i++) 1504 if (rs->dev[i].data_dev && 1505 test_bit(WriteMostly, &rs->dev[i].rdev.flags)) 1506 DMEMIT(" write_mostly %u", i); 1507 1508 if (rs->ctr_flags & CTR_FLAG_MAX_WRITE_BEHIND) 1509 DMEMIT(" max_write_behind %lu", 1510 rs->md.bitmap_info.max_write_behind); 1511 1512 if (rs->ctr_flags & CTR_FLAG_STRIPE_CACHE) { 1513 struct r5conf *conf = rs->md.private; 1514 1515 /* convert from kiB to sectors */ 1516 DMEMIT(" stripe_cache %d", 1517 conf ? conf->max_nr_stripes * 2 : 0); 1518 } 1519 1520 if (rs->ctr_flags & CTR_FLAG_REGION_SIZE) 1521 DMEMIT(" region_size %lu", 1522 rs->md.bitmap_info.chunksize >> 9); 1523 1524 if (rs->ctr_flags & CTR_FLAG_RAID10_COPIES) 1525 DMEMIT(" raid10_copies %u", 1526 raid10_md_layout_to_copies(rs->md.layout)); 1527 1528 if (rs->ctr_flags & CTR_FLAG_RAID10_FORMAT) 1529 DMEMIT(" raid10_format %s", 1530 raid10_md_layout_to_format(rs->md.layout)); 1531 1532 DMEMIT(" %d", rs->md.raid_disks); 1533 for (i = 0; i < rs->md.raid_disks; i++) { 1534 if (rs->dev[i].meta_dev) 1535 DMEMIT(" %s", rs->dev[i].meta_dev->name); 1536 else 1537 DMEMIT(" -"); 1538 1539 if (rs->dev[i].data_dev) 1540 DMEMIT(" %s", rs->dev[i].data_dev->name); 1541 else 1542 DMEMIT(" -"); 1543 } 1544 } 1545 } 1546 1547 static int raid_message(struct dm_target *ti, unsigned argc, char **argv) 1548 { 1549 struct raid_set *rs = ti->private; 1550 struct mddev *mddev = &rs->md; 1551 1552 if (!strcasecmp(argv[0], "reshape")) { 1553 DMERR("Reshape not supported."); 1554 return -EINVAL; 1555 } 1556 1557 if (!mddev->pers || !mddev->pers->sync_request) 1558 return -EINVAL; 1559 1560 if (!strcasecmp(argv[0], "frozen")) 1561 set_bit(MD_RECOVERY_FROZEN, &mddev->recovery); 1562 else 1563 clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery); 1564 1565 if (!strcasecmp(argv[0], "idle") || !strcasecmp(argv[0], "frozen")) { 1566 if (mddev->sync_thread) { 1567 set_bit(MD_RECOVERY_INTR, &mddev->recovery); 1568 md_reap_sync_thread(mddev); 1569 } 1570 } else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) || 1571 test_bit(MD_RECOVERY_NEEDED, &mddev->recovery)) 1572 return -EBUSY; 1573 else if (!strcasecmp(argv[0], "resync")) 1574 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); 1575 else if (!strcasecmp(argv[0], "recover")) { 1576 set_bit(MD_RECOVERY_RECOVER, &mddev->recovery); 1577 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); 1578 } else { 1579 if (!strcasecmp(argv[0], "check")) 1580 set_bit(MD_RECOVERY_CHECK, &mddev->recovery); 1581 else if (!!strcasecmp(argv[0], "repair")) 1582 return -EINVAL; 1583 set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery); 1584 set_bit(MD_RECOVERY_SYNC, &mddev->recovery); 1585 } 1586 if (mddev->ro == 2) { 1587 /* A write to sync_action is enough to justify 1588 * canceling read-auto mode 1589 */ 1590 mddev->ro = 0; 1591 if (!mddev->suspended) 1592 md_wakeup_thread(mddev->sync_thread); 1593 } 1594 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); 1595 if (!mddev->suspended) 1596 md_wakeup_thread(mddev->thread); 1597 1598 return 0; 1599 } 1600 1601 static int raid_iterate_devices(struct dm_target *ti, 1602 iterate_devices_callout_fn fn, void *data) 1603 { 1604 struct raid_set *rs = ti->private; 1605 unsigned i; 1606 int ret = 0; 1607 1608 for (i = 0; !ret && i < rs->md.raid_disks; i++) 1609 if (rs->dev[i].data_dev) 1610 ret = fn(ti, 1611 rs->dev[i].data_dev, 1612 0, /* No offset on data devs */ 1613 rs->md.dev_sectors, 1614 data); 1615 1616 return ret; 1617 } 1618 1619 static void raid_io_hints(struct dm_target *ti, struct queue_limits *limits) 1620 { 1621 struct raid_set *rs = ti->private; 1622 unsigned chunk_size = rs->md.chunk_sectors << 9; 1623 struct r5conf *conf = rs->md.private; 1624 1625 blk_limits_io_min(limits, chunk_size); 1626 blk_limits_io_opt(limits, chunk_size * (conf->raid_disks - conf->max_degraded)); 1627 } 1628 1629 static void raid_presuspend(struct dm_target *ti) 1630 { 1631 struct raid_set *rs = ti->private; 1632 1633 md_stop_writes(&rs->md); 1634 } 1635 1636 static void raid_postsuspend(struct dm_target *ti) 1637 { 1638 struct raid_set *rs = ti->private; 1639 1640 mddev_suspend(&rs->md); 1641 } 1642 1643 static void attempt_restore_of_faulty_devices(struct raid_set *rs) 1644 { 1645 int i; 1646 uint64_t failed_devices, cleared_failed_devices = 0; 1647 unsigned long flags; 1648 struct dm_raid_superblock *sb; 1649 struct md_rdev *r; 1650 1651 for (i = 0; i < rs->md.raid_disks; i++) { 1652 r = &rs->dev[i].rdev; 1653 if (test_bit(Faulty, &r->flags) && r->sb_page && 1654 sync_page_io(r, 0, r->sb_size, r->sb_page, READ, 1)) { 1655 DMINFO("Faulty %s device #%d has readable super block." 1656 " Attempting to revive it.", 1657 rs->raid_type->name, i); 1658 1659 /* 1660 * Faulty bit may be set, but sometimes the array can 1661 * be suspended before the personalities can respond 1662 * by removing the device from the array (i.e. calling 1663 * 'hot_remove_disk'). If they haven't yet removed 1664 * the failed device, its 'raid_disk' number will be 1665 * '>= 0' - meaning we must call this function 1666 * ourselves. 1667 */ 1668 if ((r->raid_disk >= 0) && 1669 (r->mddev->pers->hot_remove_disk(r->mddev, r) != 0)) 1670 /* Failed to revive this device, try next */ 1671 continue; 1672 1673 r->raid_disk = i; 1674 r->saved_raid_disk = i; 1675 flags = r->flags; 1676 clear_bit(Faulty, &r->flags); 1677 clear_bit(WriteErrorSeen, &r->flags); 1678 clear_bit(In_sync, &r->flags); 1679 if (r->mddev->pers->hot_add_disk(r->mddev, r)) { 1680 r->raid_disk = -1; 1681 r->saved_raid_disk = -1; 1682 r->flags = flags; 1683 } else { 1684 r->recovery_offset = 0; 1685 cleared_failed_devices |= 1 << i; 1686 } 1687 } 1688 } 1689 if (cleared_failed_devices) { 1690 rdev_for_each(r, &rs->md) { 1691 sb = page_address(r->sb_page); 1692 failed_devices = le64_to_cpu(sb->failed_devices); 1693 failed_devices &= ~cleared_failed_devices; 1694 sb->failed_devices = cpu_to_le64(failed_devices); 1695 } 1696 } 1697 } 1698 1699 static void raid_resume(struct dm_target *ti) 1700 { 1701 struct raid_set *rs = ti->private; 1702 1703 if (rs->raid_type->level) { 1704 set_bit(MD_CHANGE_DEVS, &rs->md.flags); 1705 1706 if (!rs->bitmap_loaded) { 1707 bitmap_load(&rs->md); 1708 rs->bitmap_loaded = 1; 1709 } else { 1710 /* 1711 * A secondary resume while the device is active. 1712 * Take this opportunity to check whether any failed 1713 * devices are reachable again. 1714 */ 1715 attempt_restore_of_faulty_devices(rs); 1716 } 1717 1718 clear_bit(MD_RECOVERY_FROZEN, &rs->md.recovery); 1719 } 1720 1721 mddev_resume(&rs->md); 1722 } 1723 1724 static struct target_type raid_target = { 1725 .name = "raid", 1726 .version = {1, 8, 0}, 1727 .module = THIS_MODULE, 1728 .ctr = raid_ctr, 1729 .dtr = raid_dtr, 1730 .map = raid_map, 1731 .status = raid_status, 1732 .message = raid_message, 1733 .iterate_devices = raid_iterate_devices, 1734 .io_hints = raid_io_hints, 1735 .presuspend = raid_presuspend, 1736 .postsuspend = raid_postsuspend, 1737 .resume = raid_resume, 1738 }; 1739 1740 static int __init dm_raid_init(void) 1741 { 1742 DMINFO("Loading target version %u.%u.%u", 1743 raid_target.version[0], 1744 raid_target.version[1], 1745 raid_target.version[2]); 1746 return dm_register_target(&raid_target); 1747 } 1748 1749 static void __exit dm_raid_exit(void) 1750 { 1751 dm_unregister_target(&raid_target); 1752 } 1753 1754 module_init(dm_raid_init); 1755 module_exit(dm_raid_exit); 1756 1757 module_param(devices_handle_discard_safely, bool, 0644); 1758 MODULE_PARM_DESC(devices_handle_discard_safely, 1759 "Set to Y if all devices in each array reliably return zeroes on reads from discarded regions"); 1760 1761 MODULE_DESCRIPTION(DM_NAME " raid4/5/6 target"); 1762 MODULE_ALIAS("dm-raid1"); 1763 MODULE_ALIAS("dm-raid10"); 1764 MODULE_ALIAS("dm-raid4"); 1765 MODULE_ALIAS("dm-raid5"); 1766 MODULE_ALIAS("dm-raid6"); 1767 MODULE_AUTHOR("Neil Brown <dm-devel@redhat.com>"); 1768 MODULE_LICENSE("GPL"); 1769