1 /* 2 * Copyright (C) 2010-2011 Neil Brown 3 * Copyright (C) 2010-2011 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 21 /* 22 * The following flags are used by dm-raid.c to set up the array state. 23 * They must be cleared before md_run is called. 24 */ 25 #define FirstUse 10 /* rdev flag */ 26 27 struct raid_dev { 28 /* 29 * Two DM devices, one to hold metadata and one to hold the 30 * actual data/parity. The reason for this is to not confuse 31 * ti->len and give more flexibility in altering size and 32 * characteristics. 33 * 34 * While it is possible for this device to be associated 35 * with a different physical device than the data_dev, it 36 * is intended for it to be the same. 37 * |--------- Physical Device ---------| 38 * |- meta_dev -|------ data_dev ------| 39 */ 40 struct dm_dev *meta_dev; 41 struct dm_dev *data_dev; 42 struct md_rdev rdev; 43 }; 44 45 /* 46 * Flags for rs->print_flags field. 47 */ 48 #define DMPF_SYNC 0x1 49 #define DMPF_NOSYNC 0x2 50 #define DMPF_REBUILD 0x4 51 #define DMPF_DAEMON_SLEEP 0x8 52 #define DMPF_MIN_RECOVERY_RATE 0x10 53 #define DMPF_MAX_RECOVERY_RATE 0x20 54 #define DMPF_MAX_WRITE_BEHIND 0x40 55 #define DMPF_STRIPE_CACHE 0x80 56 #define DMPF_REGION_SIZE 0x100 57 #define DMPF_RAID10_COPIES 0x200 58 #define DMPF_RAID10_FORMAT 0x400 59 60 struct raid_set { 61 struct dm_target *ti; 62 63 uint32_t bitmap_loaded; 64 uint32_t print_flags; 65 66 struct mddev md; 67 struct raid_type *raid_type; 68 struct dm_target_callbacks callbacks; 69 70 struct raid_dev dev[0]; 71 }; 72 73 /* Supported raid types and properties. */ 74 static struct raid_type { 75 const char *name; /* RAID algorithm. */ 76 const char *descr; /* Descriptor text for logging. */ 77 const unsigned parity_devs; /* # of parity devices. */ 78 const unsigned minimal_devs; /* minimal # of devices in set. */ 79 const unsigned level; /* RAID level. */ 80 const unsigned algorithm; /* RAID algorithm. */ 81 } raid_types[] = { 82 {"raid1", "RAID1 (mirroring)", 0, 2, 1, 0 /* NONE */}, 83 {"raid10", "RAID10 (striped mirrors)", 0, 2, 10, UINT_MAX /* Varies */}, 84 {"raid4", "RAID4 (dedicated parity disk)", 1, 2, 5, ALGORITHM_PARITY_0}, 85 {"raid5_la", "RAID5 (left asymmetric)", 1, 2, 5, ALGORITHM_LEFT_ASYMMETRIC}, 86 {"raid5_ra", "RAID5 (right asymmetric)", 1, 2, 5, ALGORITHM_RIGHT_ASYMMETRIC}, 87 {"raid5_ls", "RAID5 (left symmetric)", 1, 2, 5, ALGORITHM_LEFT_SYMMETRIC}, 88 {"raid5_rs", "RAID5 (right symmetric)", 1, 2, 5, ALGORITHM_RIGHT_SYMMETRIC}, 89 {"raid6_zr", "RAID6 (zero restart)", 2, 4, 6, ALGORITHM_ROTATING_ZERO_RESTART}, 90 {"raid6_nr", "RAID6 (N restart)", 2, 4, 6, ALGORITHM_ROTATING_N_RESTART}, 91 {"raid6_nc", "RAID6 (N continue)", 2, 4, 6, ALGORITHM_ROTATING_N_CONTINUE} 92 }; 93 94 static char *raid10_md_layout_to_format(int layout) 95 { 96 /* 97 * Bit 16 and 17 stand for "offset" and "use_far_sets" 98 * Refer to MD's raid10.c for details 99 */ 100 if ((layout & 0x10000) && (layout & 0x20000)) 101 return "offset"; 102 103 if ((layout & 0xFF) > 1) 104 return "near"; 105 106 return "far"; 107 } 108 109 static unsigned raid10_md_layout_to_copies(int layout) 110 { 111 if ((layout & 0xFF) > 1) 112 return layout & 0xFF; 113 return (layout >> 8) & 0xFF; 114 } 115 116 static int raid10_format_to_md_layout(char *format, unsigned copies) 117 { 118 unsigned n = 1, f = 1; 119 120 if (!strcmp("near", format)) 121 n = copies; 122 else 123 f = copies; 124 125 if (!strcmp("offset", format)) 126 return 0x30000 | (f << 8) | n; 127 128 if (!strcmp("far", format)) 129 return 0x20000 | (f << 8) | n; 130 131 return (f << 8) | n; 132 } 133 134 static struct raid_type *get_raid_type(char *name) 135 { 136 int i; 137 138 for (i = 0; i < ARRAY_SIZE(raid_types); i++) 139 if (!strcmp(raid_types[i].name, name)) 140 return &raid_types[i]; 141 142 return NULL; 143 } 144 145 static struct raid_set *context_alloc(struct dm_target *ti, struct raid_type *raid_type, unsigned raid_devs) 146 { 147 unsigned i; 148 struct raid_set *rs; 149 150 if (raid_devs <= raid_type->parity_devs) { 151 ti->error = "Insufficient number of devices"; 152 return ERR_PTR(-EINVAL); 153 } 154 155 rs = kzalloc(sizeof(*rs) + raid_devs * sizeof(rs->dev[0]), GFP_KERNEL); 156 if (!rs) { 157 ti->error = "Cannot allocate raid context"; 158 return ERR_PTR(-ENOMEM); 159 } 160 161 mddev_init(&rs->md); 162 163 rs->ti = ti; 164 rs->raid_type = raid_type; 165 rs->md.raid_disks = raid_devs; 166 rs->md.level = raid_type->level; 167 rs->md.new_level = rs->md.level; 168 rs->md.layout = raid_type->algorithm; 169 rs->md.new_layout = rs->md.layout; 170 rs->md.delta_disks = 0; 171 rs->md.recovery_cp = 0; 172 173 for (i = 0; i < raid_devs; i++) 174 md_rdev_init(&rs->dev[i].rdev); 175 176 /* 177 * Remaining items to be initialized by further RAID params: 178 * rs->md.persistent 179 * rs->md.external 180 * rs->md.chunk_sectors 181 * rs->md.new_chunk_sectors 182 * rs->md.dev_sectors 183 */ 184 185 return rs; 186 } 187 188 static void context_free(struct raid_set *rs) 189 { 190 int i; 191 192 for (i = 0; i < rs->md.raid_disks; i++) { 193 if (rs->dev[i].meta_dev) 194 dm_put_device(rs->ti, rs->dev[i].meta_dev); 195 md_rdev_clear(&rs->dev[i].rdev); 196 if (rs->dev[i].data_dev) 197 dm_put_device(rs->ti, rs->dev[i].data_dev); 198 } 199 200 kfree(rs); 201 } 202 203 /* 204 * For every device we have two words 205 * <meta_dev>: meta device name or '-' if missing 206 * <data_dev>: data device name or '-' if missing 207 * 208 * The following are permitted: 209 * - - 210 * - <data_dev> 211 * <meta_dev> <data_dev> 212 * 213 * The following is not allowed: 214 * <meta_dev> - 215 * 216 * This code parses those words. If there is a failure, 217 * the caller must use context_free to unwind the operations. 218 */ 219 static int dev_parms(struct raid_set *rs, char **argv) 220 { 221 int i; 222 int rebuild = 0; 223 int metadata_available = 0; 224 int ret = 0; 225 226 for (i = 0; i < rs->md.raid_disks; i++, argv += 2) { 227 rs->dev[i].rdev.raid_disk = i; 228 229 rs->dev[i].meta_dev = NULL; 230 rs->dev[i].data_dev = NULL; 231 232 /* 233 * There are no offsets, since there is a separate device 234 * for data and metadata. 235 */ 236 rs->dev[i].rdev.data_offset = 0; 237 rs->dev[i].rdev.mddev = &rs->md; 238 239 if (strcmp(argv[0], "-")) { 240 ret = dm_get_device(rs->ti, argv[0], 241 dm_table_get_mode(rs->ti->table), 242 &rs->dev[i].meta_dev); 243 rs->ti->error = "RAID metadata device lookup failure"; 244 if (ret) 245 return ret; 246 247 rs->dev[i].rdev.sb_page = alloc_page(GFP_KERNEL); 248 if (!rs->dev[i].rdev.sb_page) 249 return -ENOMEM; 250 } 251 252 if (!strcmp(argv[1], "-")) { 253 if (!test_bit(In_sync, &rs->dev[i].rdev.flags) && 254 (!rs->dev[i].rdev.recovery_offset)) { 255 rs->ti->error = "Drive designated for rebuild not specified"; 256 return -EINVAL; 257 } 258 259 rs->ti->error = "No data device supplied with metadata device"; 260 if (rs->dev[i].meta_dev) 261 return -EINVAL; 262 263 continue; 264 } 265 266 ret = dm_get_device(rs->ti, argv[1], 267 dm_table_get_mode(rs->ti->table), 268 &rs->dev[i].data_dev); 269 if (ret) { 270 rs->ti->error = "RAID device lookup failure"; 271 return ret; 272 } 273 274 if (rs->dev[i].meta_dev) { 275 metadata_available = 1; 276 rs->dev[i].rdev.meta_bdev = rs->dev[i].meta_dev->bdev; 277 } 278 rs->dev[i].rdev.bdev = rs->dev[i].data_dev->bdev; 279 list_add(&rs->dev[i].rdev.same_set, &rs->md.disks); 280 if (!test_bit(In_sync, &rs->dev[i].rdev.flags)) 281 rebuild++; 282 } 283 284 if (metadata_available) { 285 rs->md.external = 0; 286 rs->md.persistent = 1; 287 rs->md.major_version = 2; 288 } else if (rebuild && !rs->md.recovery_cp) { 289 /* 290 * Without metadata, we will not be able to tell if the array 291 * is in-sync or not - we must assume it is not. Therefore, 292 * it is impossible to rebuild a drive. 293 * 294 * Even if there is metadata, the on-disk information may 295 * indicate that the array is not in-sync and it will then 296 * fail at that time. 297 * 298 * User could specify 'nosync' option if desperate. 299 */ 300 DMERR("Unable to rebuild drive while array is not in-sync"); 301 rs->ti->error = "RAID device lookup failure"; 302 return -EINVAL; 303 } 304 305 return 0; 306 } 307 308 /* 309 * validate_region_size 310 * @rs 311 * @region_size: region size in sectors. If 0, pick a size (4MiB default). 312 * 313 * Set rs->md.bitmap_info.chunksize (which really refers to 'region size'). 314 * Ensure that (ti->len/region_size < 2^21) - required by MD bitmap. 315 * 316 * Returns: 0 on success, -EINVAL on failure. 317 */ 318 static int validate_region_size(struct raid_set *rs, unsigned long region_size) 319 { 320 unsigned long min_region_size = rs->ti->len / (1 << 21); 321 322 if (!region_size) { 323 /* 324 * Choose a reasonable default. All figures in sectors. 325 */ 326 if (min_region_size > (1 << 13)) { 327 /* If not a power of 2, make it the next power of 2 */ 328 if (min_region_size & (min_region_size - 1)) 329 region_size = 1 << fls(region_size); 330 DMINFO("Choosing default region size of %lu sectors", 331 region_size); 332 } else { 333 DMINFO("Choosing default region size of 4MiB"); 334 region_size = 1 << 13; /* sectors */ 335 } 336 } else { 337 /* 338 * Validate user-supplied value. 339 */ 340 if (region_size > rs->ti->len) { 341 rs->ti->error = "Supplied region size is too large"; 342 return -EINVAL; 343 } 344 345 if (region_size < min_region_size) { 346 DMERR("Supplied region_size (%lu sectors) below minimum (%lu)", 347 region_size, min_region_size); 348 rs->ti->error = "Supplied region size is too small"; 349 return -EINVAL; 350 } 351 352 if (!is_power_of_2(region_size)) { 353 rs->ti->error = "Region size is not a power of 2"; 354 return -EINVAL; 355 } 356 357 if (region_size < rs->md.chunk_sectors) { 358 rs->ti->error = "Region size is smaller than the chunk size"; 359 return -EINVAL; 360 } 361 } 362 363 /* 364 * Convert sectors to bytes. 365 */ 366 rs->md.bitmap_info.chunksize = (region_size << 9); 367 368 return 0; 369 } 370 371 /* 372 * validate_raid_redundancy 373 * @rs 374 * 375 * Determine if there are enough devices in the array that haven't 376 * failed (or are being rebuilt) to form a usable array. 377 * 378 * Returns: 0 on success, -EINVAL on failure. 379 */ 380 static int validate_raid_redundancy(struct raid_set *rs) 381 { 382 unsigned i, rebuild_cnt = 0; 383 unsigned rebuilds_per_group = 0, copies, d; 384 unsigned group_size, last_group_start; 385 386 for (i = 0; i < rs->md.raid_disks; i++) 387 if (!test_bit(In_sync, &rs->dev[i].rdev.flags) || 388 !rs->dev[i].rdev.sb_page) 389 rebuild_cnt++; 390 391 switch (rs->raid_type->level) { 392 case 1: 393 if (rebuild_cnt >= rs->md.raid_disks) 394 goto too_many; 395 break; 396 case 4: 397 case 5: 398 case 6: 399 if (rebuild_cnt > rs->raid_type->parity_devs) 400 goto too_many; 401 break; 402 case 10: 403 copies = raid10_md_layout_to_copies(rs->md.layout); 404 if (rebuild_cnt < copies) 405 break; 406 407 /* 408 * It is possible to have a higher rebuild count for RAID10, 409 * as long as the failed devices occur in different mirror 410 * groups (i.e. different stripes). 411 * 412 * When checking "near" format, make sure no adjacent devices 413 * have failed beyond what can be handled. In addition to the 414 * simple case where the number of devices is a multiple of the 415 * number of copies, we must also handle cases where the number 416 * of devices is not a multiple of the number of copies. 417 * E.g. dev1 dev2 dev3 dev4 dev5 418 * A A B B C 419 * C D D E E 420 */ 421 if (!strcmp("near", raid10_md_layout_to_format(rs->md.layout))) { 422 for (i = 0; i < rs->md.raid_disks * copies; i++) { 423 if (!(i % copies)) 424 rebuilds_per_group = 0; 425 d = i % rs->md.raid_disks; 426 if ((!rs->dev[d].rdev.sb_page || 427 !test_bit(In_sync, &rs->dev[d].rdev.flags)) && 428 (++rebuilds_per_group >= copies)) 429 goto too_many; 430 } 431 break; 432 } 433 434 /* 435 * When checking "far" and "offset" formats, we need to ensure 436 * that the device that holds its copy is not also dead or 437 * being rebuilt. (Note that "far" and "offset" formats only 438 * support two copies right now. These formats also only ever 439 * use the 'use_far_sets' variant.) 440 * 441 * This check is somewhat complicated by the need to account 442 * for arrays that are not a multiple of (far) copies. This 443 * results in the need to treat the last (potentially larger) 444 * set differently. 445 */ 446 group_size = (rs->md.raid_disks / copies); 447 last_group_start = (rs->md.raid_disks / group_size) - 1; 448 last_group_start *= group_size; 449 for (i = 0; i < rs->md.raid_disks; i++) { 450 if (!(i % copies) && !(i > last_group_start)) 451 rebuilds_per_group = 0; 452 if ((!rs->dev[i].rdev.sb_page || 453 !test_bit(In_sync, &rs->dev[i].rdev.flags)) && 454 (++rebuilds_per_group >= copies)) 455 goto too_many; 456 } 457 break; 458 default: 459 if (rebuild_cnt) 460 return -EINVAL; 461 } 462 463 return 0; 464 465 too_many: 466 return -EINVAL; 467 } 468 469 /* 470 * Possible arguments are... 471 * <chunk_size> [optional_args] 472 * 473 * Argument definitions 474 * <chunk_size> The number of sectors per disk that 475 * will form the "stripe" 476 * [[no]sync] Force or prevent recovery of the 477 * entire array 478 * [rebuild <idx>] Rebuild the drive indicated by the index 479 * [daemon_sleep <ms>] Time between bitmap daemon work to 480 * clear bits 481 * [min_recovery_rate <kB/sec/disk>] Throttle RAID initialization 482 * [max_recovery_rate <kB/sec/disk>] Throttle RAID initialization 483 * [write_mostly <idx>] Indicate a write mostly drive via index 484 * [max_write_behind <sectors>] See '-write-behind=' (man mdadm) 485 * [stripe_cache <sectors>] Stripe cache size for higher RAIDs 486 * [region_size <sectors>] Defines granularity of bitmap 487 * 488 * RAID10-only options: 489 * [raid10_copies <# copies>] Number of copies. (Default: 2) 490 * [raid10_format <near|far|offset>] Layout algorithm. (Default: near) 491 */ 492 static int parse_raid_params(struct raid_set *rs, char **argv, 493 unsigned num_raid_params) 494 { 495 char *raid10_format = "near"; 496 unsigned raid10_copies = 2; 497 unsigned i; 498 unsigned long value, region_size = 0; 499 sector_t sectors_per_dev = rs->ti->len; 500 sector_t max_io_len; 501 char *key; 502 503 /* 504 * First, parse the in-order required arguments 505 * "chunk_size" is the only argument of this type. 506 */ 507 if ((kstrtoul(argv[0], 10, &value) < 0)) { 508 rs->ti->error = "Bad chunk size"; 509 return -EINVAL; 510 } else if (rs->raid_type->level == 1) { 511 if (value) 512 DMERR("Ignoring chunk size parameter for RAID 1"); 513 value = 0; 514 } else if (!is_power_of_2(value)) { 515 rs->ti->error = "Chunk size must be a power of 2"; 516 return -EINVAL; 517 } else if (value < 8) { 518 rs->ti->error = "Chunk size value is too small"; 519 return -EINVAL; 520 } 521 522 rs->md.new_chunk_sectors = rs->md.chunk_sectors = value; 523 argv++; 524 num_raid_params--; 525 526 /* 527 * We set each individual device as In_sync with a completed 528 * 'recovery_offset'. If there has been a device failure or 529 * replacement then one of the following cases applies: 530 * 531 * 1) User specifies 'rebuild'. 532 * - Device is reset when param is read. 533 * 2) A new device is supplied. 534 * - No matching superblock found, resets device. 535 * 3) Device failure was transient and returns on reload. 536 * - Failure noticed, resets device for bitmap replay. 537 * 4) Device hadn't completed recovery after previous failure. 538 * - Superblock is read and overrides recovery_offset. 539 * 540 * What is found in the superblocks of the devices is always 541 * authoritative, unless 'rebuild' or '[no]sync' was specified. 542 */ 543 for (i = 0; i < rs->md.raid_disks; i++) { 544 set_bit(In_sync, &rs->dev[i].rdev.flags); 545 rs->dev[i].rdev.recovery_offset = MaxSector; 546 } 547 548 /* 549 * Second, parse the unordered optional arguments 550 */ 551 for (i = 0; i < num_raid_params; i++) { 552 if (!strcasecmp(argv[i], "nosync")) { 553 rs->md.recovery_cp = MaxSector; 554 rs->print_flags |= DMPF_NOSYNC; 555 continue; 556 } 557 if (!strcasecmp(argv[i], "sync")) { 558 rs->md.recovery_cp = 0; 559 rs->print_flags |= DMPF_SYNC; 560 continue; 561 } 562 563 /* The rest of the optional arguments come in key/value pairs */ 564 if ((i + 1) >= num_raid_params) { 565 rs->ti->error = "Wrong number of raid parameters given"; 566 return -EINVAL; 567 } 568 569 key = argv[i++]; 570 571 /* Parameters that take a string value are checked here. */ 572 if (!strcasecmp(key, "raid10_format")) { 573 if (rs->raid_type->level != 10) { 574 rs->ti->error = "'raid10_format' is an invalid parameter for this RAID type"; 575 return -EINVAL; 576 } 577 if (strcmp("near", argv[i]) && 578 strcmp("far", argv[i]) && 579 strcmp("offset", argv[i])) { 580 rs->ti->error = "Invalid 'raid10_format' value given"; 581 return -EINVAL; 582 } 583 raid10_format = argv[i]; 584 rs->print_flags |= DMPF_RAID10_FORMAT; 585 continue; 586 } 587 588 if (kstrtoul(argv[i], 10, &value) < 0) { 589 rs->ti->error = "Bad numerical argument given in raid params"; 590 return -EINVAL; 591 } 592 593 /* Parameters that take a numeric value are checked here */ 594 if (!strcasecmp(key, "rebuild")) { 595 if (value >= rs->md.raid_disks) { 596 rs->ti->error = "Invalid rebuild index given"; 597 return -EINVAL; 598 } 599 clear_bit(In_sync, &rs->dev[value].rdev.flags); 600 rs->dev[value].rdev.recovery_offset = 0; 601 rs->print_flags |= DMPF_REBUILD; 602 } else if (!strcasecmp(key, "write_mostly")) { 603 if (rs->raid_type->level != 1) { 604 rs->ti->error = "write_mostly option is only valid for RAID1"; 605 return -EINVAL; 606 } 607 if (value >= rs->md.raid_disks) { 608 rs->ti->error = "Invalid write_mostly drive index given"; 609 return -EINVAL; 610 } 611 set_bit(WriteMostly, &rs->dev[value].rdev.flags); 612 } else if (!strcasecmp(key, "max_write_behind")) { 613 if (rs->raid_type->level != 1) { 614 rs->ti->error = "max_write_behind option is only valid for RAID1"; 615 return -EINVAL; 616 } 617 rs->print_flags |= DMPF_MAX_WRITE_BEHIND; 618 619 /* 620 * In device-mapper, we specify things in sectors, but 621 * MD records this value in kB 622 */ 623 value /= 2; 624 if (value > COUNTER_MAX) { 625 rs->ti->error = "Max write-behind limit out of range"; 626 return -EINVAL; 627 } 628 rs->md.bitmap_info.max_write_behind = value; 629 } else if (!strcasecmp(key, "daemon_sleep")) { 630 rs->print_flags |= DMPF_DAEMON_SLEEP; 631 if (!value || (value > MAX_SCHEDULE_TIMEOUT)) { 632 rs->ti->error = "daemon sleep period out of range"; 633 return -EINVAL; 634 } 635 rs->md.bitmap_info.daemon_sleep = value; 636 } else if (!strcasecmp(key, "stripe_cache")) { 637 rs->print_flags |= DMPF_STRIPE_CACHE; 638 639 /* 640 * In device-mapper, we specify things in sectors, but 641 * MD records this value in kB 642 */ 643 value /= 2; 644 645 if ((rs->raid_type->level != 5) && 646 (rs->raid_type->level != 6)) { 647 rs->ti->error = "Inappropriate argument: stripe_cache"; 648 return -EINVAL; 649 } 650 if (raid5_set_cache_size(&rs->md, (int)value)) { 651 rs->ti->error = "Bad stripe_cache size"; 652 return -EINVAL; 653 } 654 } else if (!strcasecmp(key, "min_recovery_rate")) { 655 rs->print_flags |= DMPF_MIN_RECOVERY_RATE; 656 if (value > INT_MAX) { 657 rs->ti->error = "min_recovery_rate out of range"; 658 return -EINVAL; 659 } 660 rs->md.sync_speed_min = (int)value; 661 } else if (!strcasecmp(key, "max_recovery_rate")) { 662 rs->print_flags |= DMPF_MAX_RECOVERY_RATE; 663 if (value > INT_MAX) { 664 rs->ti->error = "max_recovery_rate out of range"; 665 return -EINVAL; 666 } 667 rs->md.sync_speed_max = (int)value; 668 } else if (!strcasecmp(key, "region_size")) { 669 rs->print_flags |= DMPF_REGION_SIZE; 670 region_size = value; 671 } else if (!strcasecmp(key, "raid10_copies") && 672 (rs->raid_type->level == 10)) { 673 if ((value < 2) || (value > 0xFF)) { 674 rs->ti->error = "Bad value for 'raid10_copies'"; 675 return -EINVAL; 676 } 677 rs->print_flags |= DMPF_RAID10_COPIES; 678 raid10_copies = value; 679 } else { 680 DMERR("Unable to parse RAID parameter: %s", key); 681 rs->ti->error = "Unable to parse RAID parameters"; 682 return -EINVAL; 683 } 684 } 685 686 if (validate_region_size(rs, region_size)) 687 return -EINVAL; 688 689 if (rs->md.chunk_sectors) 690 max_io_len = rs->md.chunk_sectors; 691 else 692 max_io_len = region_size; 693 694 if (dm_set_target_max_io_len(rs->ti, max_io_len)) 695 return -EINVAL; 696 697 if (rs->raid_type->level == 10) { 698 if (raid10_copies > rs->md.raid_disks) { 699 rs->ti->error = "Not enough devices to satisfy specification"; 700 return -EINVAL; 701 } 702 703 /* 704 * If the format is not "near", we only support 705 * two copies at the moment. 706 */ 707 if (strcmp("near", raid10_format) && (raid10_copies > 2)) { 708 rs->ti->error = "Too many copies for given RAID10 format."; 709 return -EINVAL; 710 } 711 712 /* (Len * #mirrors) / #devices */ 713 sectors_per_dev = rs->ti->len * raid10_copies; 714 sector_div(sectors_per_dev, rs->md.raid_disks); 715 716 rs->md.layout = raid10_format_to_md_layout(raid10_format, 717 raid10_copies); 718 rs->md.new_layout = rs->md.layout; 719 } else if ((rs->raid_type->level > 1) && 720 sector_div(sectors_per_dev, 721 (rs->md.raid_disks - rs->raid_type->parity_devs))) { 722 rs->ti->error = "Target length not divisible by number of data devices"; 723 return -EINVAL; 724 } 725 rs->md.dev_sectors = sectors_per_dev; 726 727 /* Assume there are no metadata devices until the drives are parsed */ 728 rs->md.persistent = 0; 729 rs->md.external = 1; 730 731 return 0; 732 } 733 734 static void do_table_event(struct work_struct *ws) 735 { 736 struct raid_set *rs = container_of(ws, struct raid_set, md.event_work); 737 738 dm_table_event(rs->ti->table); 739 } 740 741 static int raid_is_congested(struct dm_target_callbacks *cb, int bits) 742 { 743 struct raid_set *rs = container_of(cb, struct raid_set, callbacks); 744 745 if (rs->raid_type->level == 1) 746 return md_raid1_congested(&rs->md, bits); 747 748 if (rs->raid_type->level == 10) 749 return md_raid10_congested(&rs->md, bits); 750 751 return md_raid5_congested(&rs->md, bits); 752 } 753 754 /* 755 * This structure is never routinely used by userspace, unlike md superblocks. 756 * Devices with this superblock should only ever be accessed via device-mapper. 757 */ 758 #define DM_RAID_MAGIC 0x64526D44 759 struct dm_raid_superblock { 760 __le32 magic; /* "DmRd" */ 761 __le32 features; /* Used to indicate possible future changes */ 762 763 __le32 num_devices; /* Number of devices in this array. (Max 64) */ 764 __le32 array_position; /* The position of this drive in the array */ 765 766 __le64 events; /* Incremented by md when superblock updated */ 767 __le64 failed_devices; /* Bit field of devices to indicate failures */ 768 769 /* 770 * This offset tracks the progress of the repair or replacement of 771 * an individual drive. 772 */ 773 __le64 disk_recovery_offset; 774 775 /* 776 * This offset tracks the progress of the initial array 777 * synchronisation/parity calculation. 778 */ 779 __le64 array_resync_offset; 780 781 /* 782 * RAID characteristics 783 */ 784 __le32 level; 785 __le32 layout; 786 __le32 stripe_sectors; 787 788 __u8 pad[452]; /* Round struct to 512 bytes. */ 789 /* Always set to 0 when writing. */ 790 } __packed; 791 792 static int read_disk_sb(struct md_rdev *rdev, int size) 793 { 794 BUG_ON(!rdev->sb_page); 795 796 if (rdev->sb_loaded) 797 return 0; 798 799 if (!sync_page_io(rdev, 0, size, rdev->sb_page, READ, 1)) { 800 DMERR("Failed to read superblock of device at position %d", 801 rdev->raid_disk); 802 md_error(rdev->mddev, rdev); 803 return -EINVAL; 804 } 805 806 rdev->sb_loaded = 1; 807 808 return 0; 809 } 810 811 static void super_sync(struct mddev *mddev, struct md_rdev *rdev) 812 { 813 int i; 814 uint64_t failed_devices; 815 struct dm_raid_superblock *sb; 816 struct raid_set *rs = container_of(mddev, struct raid_set, md); 817 818 sb = page_address(rdev->sb_page); 819 failed_devices = le64_to_cpu(sb->failed_devices); 820 821 for (i = 0; i < mddev->raid_disks; i++) 822 if (!rs->dev[i].data_dev || 823 test_bit(Faulty, &(rs->dev[i].rdev.flags))) 824 failed_devices |= (1ULL << i); 825 826 memset(sb, 0, sizeof(*sb)); 827 828 sb->magic = cpu_to_le32(DM_RAID_MAGIC); 829 sb->features = cpu_to_le32(0); /* No features yet */ 830 831 sb->num_devices = cpu_to_le32(mddev->raid_disks); 832 sb->array_position = cpu_to_le32(rdev->raid_disk); 833 834 sb->events = cpu_to_le64(mddev->events); 835 sb->failed_devices = cpu_to_le64(failed_devices); 836 837 sb->disk_recovery_offset = cpu_to_le64(rdev->recovery_offset); 838 sb->array_resync_offset = cpu_to_le64(mddev->recovery_cp); 839 840 sb->level = cpu_to_le32(mddev->level); 841 sb->layout = cpu_to_le32(mddev->layout); 842 sb->stripe_sectors = cpu_to_le32(mddev->chunk_sectors); 843 } 844 845 /* 846 * super_load 847 * 848 * This function creates a superblock if one is not found on the device 849 * and will decide which superblock to use if there's a choice. 850 * 851 * Return: 1 if use rdev, 0 if use refdev, -Exxx otherwise 852 */ 853 static int super_load(struct md_rdev *rdev, struct md_rdev *refdev) 854 { 855 int ret; 856 struct dm_raid_superblock *sb; 857 struct dm_raid_superblock *refsb; 858 uint64_t events_sb, events_refsb; 859 860 rdev->sb_start = 0; 861 rdev->sb_size = sizeof(*sb); 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->print_flags & (DMPF_SYNC | DMPF_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 mddev *mddev, struct md_rdev *rdev) 1029 { 1030 struct dm_raid_superblock *sb = page_address(rdev->sb_page); 1031 1032 /* 1033 * If mddev->events is not set, we know we have not yet initialized 1034 * the array. 1035 */ 1036 if (!mddev->events && super_init_validation(mddev, rdev)) 1037 return -EINVAL; 1038 1039 mddev->bitmap_info.offset = 4096 >> 9; /* Enable bitmap creation */ 1040 rdev->mddev->bitmap_info.default_offset = 4096 >> 9; 1041 if (!test_bit(FirstUse, &rdev->flags)) { 1042 rdev->recovery_offset = le64_to_cpu(sb->disk_recovery_offset); 1043 if (rdev->recovery_offset != MaxSector) 1044 clear_bit(In_sync, &rdev->flags); 1045 } 1046 1047 /* 1048 * If a device comes back, set it as not In_sync and no longer faulty. 1049 */ 1050 if (test_bit(Faulty, &rdev->flags)) { 1051 clear_bit(Faulty, &rdev->flags); 1052 clear_bit(In_sync, &rdev->flags); 1053 rdev->saved_raid_disk = rdev->raid_disk; 1054 rdev->recovery_offset = 0; 1055 } 1056 1057 clear_bit(FirstUse, &rdev->flags); 1058 1059 return 0; 1060 } 1061 1062 /* 1063 * Analyse superblocks and select the freshest. 1064 */ 1065 static int analyse_superblocks(struct dm_target *ti, struct raid_set *rs) 1066 { 1067 int ret; 1068 struct raid_dev *dev; 1069 struct md_rdev *rdev, *tmp, *freshest; 1070 struct mddev *mddev = &rs->md; 1071 1072 freshest = NULL; 1073 rdev_for_each_safe(rdev, tmp, mddev) { 1074 /* 1075 * Skipping super_load due to DMPF_SYNC will cause 1076 * the array to undergo initialization again as 1077 * though it were new. This is the intended effect 1078 * of the "sync" directive. 1079 * 1080 * When reshaping capability is added, we must ensure 1081 * that the "sync" directive is disallowed during the 1082 * reshape. 1083 */ 1084 if (rs->print_flags & DMPF_SYNC) 1085 continue; 1086 1087 if (!rdev->meta_bdev) 1088 continue; 1089 1090 ret = super_load(rdev, freshest); 1091 1092 switch (ret) { 1093 case 1: 1094 freshest = rdev; 1095 break; 1096 case 0: 1097 break; 1098 default: 1099 dev = container_of(rdev, struct raid_dev, rdev); 1100 if (dev->meta_dev) 1101 dm_put_device(ti, dev->meta_dev); 1102 1103 dev->meta_dev = NULL; 1104 rdev->meta_bdev = NULL; 1105 1106 if (rdev->sb_page) 1107 put_page(rdev->sb_page); 1108 1109 rdev->sb_page = NULL; 1110 1111 rdev->sb_loaded = 0; 1112 1113 /* 1114 * We might be able to salvage the data device 1115 * even though the meta device has failed. For 1116 * now, we behave as though '- -' had been 1117 * set for this device in the table. 1118 */ 1119 if (dev->data_dev) 1120 dm_put_device(ti, dev->data_dev); 1121 1122 dev->data_dev = NULL; 1123 rdev->bdev = NULL; 1124 1125 list_del(&rdev->same_set); 1126 } 1127 } 1128 1129 if (!freshest) 1130 return 0; 1131 1132 if (validate_raid_redundancy(rs)) { 1133 rs->ti->error = "Insufficient redundancy to activate array"; 1134 return -EINVAL; 1135 } 1136 1137 /* 1138 * Validation of the freshest device provides the source of 1139 * validation for the remaining devices. 1140 */ 1141 ti->error = "Unable to assemble array: Invalid superblocks"; 1142 if (super_validate(mddev, freshest)) 1143 return -EINVAL; 1144 1145 rdev_for_each(rdev, mddev) 1146 if ((rdev != freshest) && super_validate(mddev, rdev)) 1147 return -EINVAL; 1148 1149 return 0; 1150 } 1151 1152 /* 1153 * Construct a RAID4/5/6 mapping: 1154 * Args: 1155 * <raid_type> <#raid_params> <raid_params> \ 1156 * <#raid_devs> { <meta_dev1> <dev1> .. <meta_devN> <devN> } 1157 * 1158 * <raid_params> varies by <raid_type>. See 'parse_raid_params' for 1159 * details on possible <raid_params>. 1160 */ 1161 static int raid_ctr(struct dm_target *ti, unsigned argc, char **argv) 1162 { 1163 int ret; 1164 struct raid_type *rt; 1165 unsigned long num_raid_params, num_raid_devs; 1166 struct raid_set *rs = NULL; 1167 1168 /* Must have at least <raid_type> <#raid_params> */ 1169 if (argc < 2) { 1170 ti->error = "Too few arguments"; 1171 return -EINVAL; 1172 } 1173 1174 /* raid type */ 1175 rt = get_raid_type(argv[0]); 1176 if (!rt) { 1177 ti->error = "Unrecognised raid_type"; 1178 return -EINVAL; 1179 } 1180 argc--; 1181 argv++; 1182 1183 /* number of RAID parameters */ 1184 if (kstrtoul(argv[0], 10, &num_raid_params) < 0) { 1185 ti->error = "Cannot understand number of RAID parameters"; 1186 return -EINVAL; 1187 } 1188 argc--; 1189 argv++; 1190 1191 /* Skip over RAID params for now and find out # of devices */ 1192 if (num_raid_params + 1 > argc) { 1193 ti->error = "Arguments do not agree with counts given"; 1194 return -EINVAL; 1195 } 1196 1197 if ((kstrtoul(argv[num_raid_params], 10, &num_raid_devs) < 0) || 1198 (num_raid_devs >= INT_MAX)) { 1199 ti->error = "Cannot understand number of raid devices"; 1200 return -EINVAL; 1201 } 1202 1203 rs = context_alloc(ti, rt, (unsigned)num_raid_devs); 1204 if (IS_ERR(rs)) 1205 return PTR_ERR(rs); 1206 1207 ret = parse_raid_params(rs, argv, (unsigned)num_raid_params); 1208 if (ret) 1209 goto bad; 1210 1211 ret = -EINVAL; 1212 1213 argc -= num_raid_params + 1; /* +1: we already have num_raid_devs */ 1214 argv += num_raid_params + 1; 1215 1216 if (argc != (num_raid_devs * 2)) { 1217 ti->error = "Supplied RAID devices does not match the count given"; 1218 goto bad; 1219 } 1220 1221 ret = dev_parms(rs, argv); 1222 if (ret) 1223 goto bad; 1224 1225 rs->md.sync_super = super_sync; 1226 ret = analyse_superblocks(ti, rs); 1227 if (ret) 1228 goto bad; 1229 1230 INIT_WORK(&rs->md.event_work, do_table_event); 1231 ti->private = rs; 1232 ti->num_flush_bios = 1; 1233 1234 mutex_lock(&rs->md.reconfig_mutex); 1235 ret = md_run(&rs->md); 1236 rs->md.in_sync = 0; /* Assume already marked dirty */ 1237 mutex_unlock(&rs->md.reconfig_mutex); 1238 1239 if (ret) { 1240 ti->error = "Fail to run raid array"; 1241 goto bad; 1242 } 1243 1244 if (ti->len != rs->md.array_sectors) { 1245 ti->error = "Array size does not match requested target length"; 1246 ret = -EINVAL; 1247 goto size_mismatch; 1248 } 1249 rs->callbacks.congested_fn = raid_is_congested; 1250 dm_table_add_target_callbacks(ti->table, &rs->callbacks); 1251 1252 mddev_suspend(&rs->md); 1253 return 0; 1254 1255 size_mismatch: 1256 md_stop(&rs->md); 1257 bad: 1258 context_free(rs); 1259 1260 return ret; 1261 } 1262 1263 static void raid_dtr(struct dm_target *ti) 1264 { 1265 struct raid_set *rs = ti->private; 1266 1267 list_del_init(&rs->callbacks.list); 1268 md_stop(&rs->md); 1269 context_free(rs); 1270 } 1271 1272 static int raid_map(struct dm_target *ti, struct bio *bio) 1273 { 1274 struct raid_set *rs = ti->private; 1275 struct mddev *mddev = &rs->md; 1276 1277 mddev->pers->make_request(mddev, bio); 1278 1279 return DM_MAPIO_SUBMITTED; 1280 } 1281 1282 static const char *decipher_sync_action(struct mddev *mddev) 1283 { 1284 if (test_bit(MD_RECOVERY_FROZEN, &mddev->recovery)) 1285 return "frozen"; 1286 1287 if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) || 1288 (!mddev->ro && test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))) { 1289 if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)) 1290 return "reshape"; 1291 1292 if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) { 1293 if (!test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) 1294 return "resync"; 1295 else if (test_bit(MD_RECOVERY_CHECK, &mddev->recovery)) 1296 return "check"; 1297 return "repair"; 1298 } 1299 1300 if (test_bit(MD_RECOVERY_RECOVER, &mddev->recovery)) 1301 return "recover"; 1302 } 1303 1304 return "idle"; 1305 } 1306 1307 static void raid_status(struct dm_target *ti, status_type_t type, 1308 unsigned status_flags, char *result, unsigned maxlen) 1309 { 1310 struct raid_set *rs = ti->private; 1311 unsigned raid_param_cnt = 1; /* at least 1 for chunksize */ 1312 unsigned sz = 0; 1313 int i, array_in_sync = 0; 1314 sector_t sync; 1315 1316 switch (type) { 1317 case STATUSTYPE_INFO: 1318 DMEMIT("%s %d ", rs->raid_type->name, rs->md.raid_disks); 1319 1320 if (test_bit(MD_RECOVERY_RUNNING, &rs->md.recovery)) 1321 sync = rs->md.curr_resync_completed; 1322 else 1323 sync = rs->md.recovery_cp; 1324 1325 if (sync >= rs->md.resync_max_sectors) { 1326 /* 1327 * Sync complete. 1328 */ 1329 array_in_sync = 1; 1330 sync = rs->md.resync_max_sectors; 1331 } else if (test_bit(MD_RECOVERY_REQUESTED, &rs->md.recovery)) { 1332 /* 1333 * If "check" or "repair" is occurring, the array has 1334 * undergone and initial sync and the health characters 1335 * should not be 'a' anymore. 1336 */ 1337 array_in_sync = 1; 1338 } else { 1339 /* 1340 * The array may be doing an initial sync, or it may 1341 * be rebuilding individual components. If all the 1342 * devices are In_sync, then it is the array that is 1343 * being initialized. 1344 */ 1345 for (i = 0; i < rs->md.raid_disks; i++) 1346 if (!test_bit(In_sync, &rs->dev[i].rdev.flags)) 1347 array_in_sync = 1; 1348 } 1349 1350 /* 1351 * Status characters: 1352 * 'D' = Dead/Failed device 1353 * 'a' = Alive but not in-sync 1354 * 'A' = Alive and in-sync 1355 */ 1356 for (i = 0; i < rs->md.raid_disks; i++) { 1357 if (test_bit(Faulty, &rs->dev[i].rdev.flags)) 1358 DMEMIT("D"); 1359 else if (!array_in_sync || 1360 !test_bit(In_sync, &rs->dev[i].rdev.flags)) 1361 DMEMIT("a"); 1362 else 1363 DMEMIT("A"); 1364 } 1365 1366 /* 1367 * In-sync ratio: 1368 * The in-sync ratio shows the progress of: 1369 * - Initializing the array 1370 * - Rebuilding a subset of devices of the array 1371 * The user can distinguish between the two by referring 1372 * to the status characters. 1373 */ 1374 DMEMIT(" %llu/%llu", 1375 (unsigned long long) sync, 1376 (unsigned long long) rs->md.resync_max_sectors); 1377 1378 /* 1379 * Sync action: 1380 * See Documentation/device-mapper/dm-raid.c for 1381 * information on each of these states. 1382 */ 1383 DMEMIT(" %s", decipher_sync_action(&rs->md)); 1384 1385 /* 1386 * resync_mismatches/mismatch_cnt 1387 * This field shows the number of discrepancies found when 1388 * performing a "check" of the array. 1389 */ 1390 DMEMIT(" %llu", 1391 (strcmp(rs->md.last_sync_action, "check")) ? 0 : 1392 (unsigned long long) 1393 atomic64_read(&rs->md.resync_mismatches)); 1394 break; 1395 case STATUSTYPE_TABLE: 1396 /* The string you would use to construct this array */ 1397 for (i = 0; i < rs->md.raid_disks; i++) { 1398 if ((rs->print_flags & DMPF_REBUILD) && 1399 rs->dev[i].data_dev && 1400 !test_bit(In_sync, &rs->dev[i].rdev.flags)) 1401 raid_param_cnt += 2; /* for rebuilds */ 1402 if (rs->dev[i].data_dev && 1403 test_bit(WriteMostly, &rs->dev[i].rdev.flags)) 1404 raid_param_cnt += 2; 1405 } 1406 1407 raid_param_cnt += (hweight32(rs->print_flags & ~DMPF_REBUILD) * 2); 1408 if (rs->print_flags & (DMPF_SYNC | DMPF_NOSYNC)) 1409 raid_param_cnt--; 1410 1411 DMEMIT("%s %u %u", rs->raid_type->name, 1412 raid_param_cnt, rs->md.chunk_sectors); 1413 1414 if ((rs->print_flags & DMPF_SYNC) && 1415 (rs->md.recovery_cp == MaxSector)) 1416 DMEMIT(" sync"); 1417 if (rs->print_flags & DMPF_NOSYNC) 1418 DMEMIT(" nosync"); 1419 1420 for (i = 0; i < rs->md.raid_disks; i++) 1421 if ((rs->print_flags & DMPF_REBUILD) && 1422 rs->dev[i].data_dev && 1423 !test_bit(In_sync, &rs->dev[i].rdev.flags)) 1424 DMEMIT(" rebuild %u", i); 1425 1426 if (rs->print_flags & DMPF_DAEMON_SLEEP) 1427 DMEMIT(" daemon_sleep %lu", 1428 rs->md.bitmap_info.daemon_sleep); 1429 1430 if (rs->print_flags & DMPF_MIN_RECOVERY_RATE) 1431 DMEMIT(" min_recovery_rate %d", rs->md.sync_speed_min); 1432 1433 if (rs->print_flags & DMPF_MAX_RECOVERY_RATE) 1434 DMEMIT(" max_recovery_rate %d", rs->md.sync_speed_max); 1435 1436 for (i = 0; i < rs->md.raid_disks; i++) 1437 if (rs->dev[i].data_dev && 1438 test_bit(WriteMostly, &rs->dev[i].rdev.flags)) 1439 DMEMIT(" write_mostly %u", i); 1440 1441 if (rs->print_flags & DMPF_MAX_WRITE_BEHIND) 1442 DMEMIT(" max_write_behind %lu", 1443 rs->md.bitmap_info.max_write_behind); 1444 1445 if (rs->print_flags & DMPF_STRIPE_CACHE) { 1446 struct r5conf *conf = rs->md.private; 1447 1448 /* convert from kiB to sectors */ 1449 DMEMIT(" stripe_cache %d", 1450 conf ? conf->max_nr_stripes * 2 : 0); 1451 } 1452 1453 if (rs->print_flags & DMPF_REGION_SIZE) 1454 DMEMIT(" region_size %lu", 1455 rs->md.bitmap_info.chunksize >> 9); 1456 1457 if (rs->print_flags & DMPF_RAID10_COPIES) 1458 DMEMIT(" raid10_copies %u", 1459 raid10_md_layout_to_copies(rs->md.layout)); 1460 1461 if (rs->print_flags & DMPF_RAID10_FORMAT) 1462 DMEMIT(" raid10_format %s", 1463 raid10_md_layout_to_format(rs->md.layout)); 1464 1465 DMEMIT(" %d", rs->md.raid_disks); 1466 for (i = 0; i < rs->md.raid_disks; i++) { 1467 if (rs->dev[i].meta_dev) 1468 DMEMIT(" %s", rs->dev[i].meta_dev->name); 1469 else 1470 DMEMIT(" -"); 1471 1472 if (rs->dev[i].data_dev) 1473 DMEMIT(" %s", rs->dev[i].data_dev->name); 1474 else 1475 DMEMIT(" -"); 1476 } 1477 } 1478 } 1479 1480 static int raid_message(struct dm_target *ti, unsigned argc, char **argv) 1481 { 1482 struct raid_set *rs = ti->private; 1483 struct mddev *mddev = &rs->md; 1484 1485 if (!strcasecmp(argv[0], "reshape")) { 1486 DMERR("Reshape not supported."); 1487 return -EINVAL; 1488 } 1489 1490 if (!mddev->pers || !mddev->pers->sync_request) 1491 return -EINVAL; 1492 1493 if (!strcasecmp(argv[0], "frozen")) 1494 set_bit(MD_RECOVERY_FROZEN, &mddev->recovery); 1495 else 1496 clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery); 1497 1498 if (!strcasecmp(argv[0], "idle") || !strcasecmp(argv[0], "frozen")) { 1499 if (mddev->sync_thread) { 1500 set_bit(MD_RECOVERY_INTR, &mddev->recovery); 1501 md_reap_sync_thread(mddev); 1502 } 1503 } else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) || 1504 test_bit(MD_RECOVERY_NEEDED, &mddev->recovery)) 1505 return -EBUSY; 1506 else if (!strcasecmp(argv[0], "resync")) 1507 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); 1508 else if (!strcasecmp(argv[0], "recover")) { 1509 set_bit(MD_RECOVERY_RECOVER, &mddev->recovery); 1510 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); 1511 } else { 1512 if (!strcasecmp(argv[0], "check")) 1513 set_bit(MD_RECOVERY_CHECK, &mddev->recovery); 1514 else if (!!strcasecmp(argv[0], "repair")) 1515 return -EINVAL; 1516 set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery); 1517 set_bit(MD_RECOVERY_SYNC, &mddev->recovery); 1518 } 1519 if (mddev->ro == 2) { 1520 /* A write to sync_action is enough to justify 1521 * canceling read-auto mode 1522 */ 1523 mddev->ro = 0; 1524 if (!mddev->suspended) 1525 md_wakeup_thread(mddev->sync_thread); 1526 } 1527 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); 1528 if (!mddev->suspended) 1529 md_wakeup_thread(mddev->thread); 1530 1531 return 0; 1532 } 1533 1534 static int raid_iterate_devices(struct dm_target *ti, 1535 iterate_devices_callout_fn fn, void *data) 1536 { 1537 struct raid_set *rs = ti->private; 1538 unsigned i; 1539 int ret = 0; 1540 1541 for (i = 0; !ret && i < rs->md.raid_disks; i++) 1542 if (rs->dev[i].data_dev) 1543 ret = fn(ti, 1544 rs->dev[i].data_dev, 1545 0, /* No offset on data devs */ 1546 rs->md.dev_sectors, 1547 data); 1548 1549 return ret; 1550 } 1551 1552 static void raid_io_hints(struct dm_target *ti, struct queue_limits *limits) 1553 { 1554 struct raid_set *rs = ti->private; 1555 unsigned chunk_size = rs->md.chunk_sectors << 9; 1556 struct r5conf *conf = rs->md.private; 1557 1558 blk_limits_io_min(limits, chunk_size); 1559 blk_limits_io_opt(limits, chunk_size * (conf->raid_disks - conf->max_degraded)); 1560 } 1561 1562 static void raid_presuspend(struct dm_target *ti) 1563 { 1564 struct raid_set *rs = ti->private; 1565 1566 md_stop_writes(&rs->md); 1567 } 1568 1569 static void raid_postsuspend(struct dm_target *ti) 1570 { 1571 struct raid_set *rs = ti->private; 1572 1573 mddev_suspend(&rs->md); 1574 } 1575 1576 static void attempt_restore_of_faulty_devices(struct raid_set *rs) 1577 { 1578 int i; 1579 uint64_t failed_devices, cleared_failed_devices = 0; 1580 unsigned long flags; 1581 struct dm_raid_superblock *sb; 1582 struct md_rdev *r; 1583 1584 for (i = 0; i < rs->md.raid_disks; i++) { 1585 r = &rs->dev[i].rdev; 1586 if (test_bit(Faulty, &r->flags) && r->sb_page && 1587 sync_page_io(r, 0, r->sb_size, r->sb_page, READ, 1)) { 1588 DMINFO("Faulty %s device #%d has readable super block." 1589 " Attempting to revive it.", 1590 rs->raid_type->name, i); 1591 1592 /* 1593 * Faulty bit may be set, but sometimes the array can 1594 * be suspended before the personalities can respond 1595 * by removing the device from the array (i.e. calling 1596 * 'hot_remove_disk'). If they haven't yet removed 1597 * the failed device, its 'raid_disk' number will be 1598 * '>= 0' - meaning we must call this function 1599 * ourselves. 1600 */ 1601 if ((r->raid_disk >= 0) && 1602 (r->mddev->pers->hot_remove_disk(r->mddev, r) != 0)) 1603 /* Failed to revive this device, try next */ 1604 continue; 1605 1606 r->raid_disk = i; 1607 r->saved_raid_disk = i; 1608 flags = r->flags; 1609 clear_bit(Faulty, &r->flags); 1610 clear_bit(WriteErrorSeen, &r->flags); 1611 clear_bit(In_sync, &r->flags); 1612 if (r->mddev->pers->hot_add_disk(r->mddev, r)) { 1613 r->raid_disk = -1; 1614 r->saved_raid_disk = -1; 1615 r->flags = flags; 1616 } else { 1617 r->recovery_offset = 0; 1618 cleared_failed_devices |= 1 << i; 1619 } 1620 } 1621 } 1622 if (cleared_failed_devices) { 1623 rdev_for_each(r, &rs->md) { 1624 sb = page_address(r->sb_page); 1625 failed_devices = le64_to_cpu(sb->failed_devices); 1626 failed_devices &= ~cleared_failed_devices; 1627 sb->failed_devices = cpu_to_le64(failed_devices); 1628 } 1629 } 1630 } 1631 1632 static void raid_resume(struct dm_target *ti) 1633 { 1634 struct raid_set *rs = ti->private; 1635 1636 set_bit(MD_CHANGE_DEVS, &rs->md.flags); 1637 if (!rs->bitmap_loaded) { 1638 bitmap_load(&rs->md); 1639 rs->bitmap_loaded = 1; 1640 } else { 1641 /* 1642 * A secondary resume while the device is active. 1643 * Take this opportunity to check whether any failed 1644 * devices are reachable again. 1645 */ 1646 attempt_restore_of_faulty_devices(rs); 1647 } 1648 1649 clear_bit(MD_RECOVERY_FROZEN, &rs->md.recovery); 1650 mddev_resume(&rs->md); 1651 } 1652 1653 static struct target_type raid_target = { 1654 .name = "raid", 1655 .version = {1, 5, 2}, 1656 .module = THIS_MODULE, 1657 .ctr = raid_ctr, 1658 .dtr = raid_dtr, 1659 .map = raid_map, 1660 .status = raid_status, 1661 .message = raid_message, 1662 .iterate_devices = raid_iterate_devices, 1663 .io_hints = raid_io_hints, 1664 .presuspend = raid_presuspend, 1665 .postsuspend = raid_postsuspend, 1666 .resume = raid_resume, 1667 }; 1668 1669 static int __init dm_raid_init(void) 1670 { 1671 DMINFO("Loading target version %u.%u.%u", 1672 raid_target.version[0], 1673 raid_target.version[1], 1674 raid_target.version[2]); 1675 return dm_register_target(&raid_target); 1676 } 1677 1678 static void __exit dm_raid_exit(void) 1679 { 1680 dm_unregister_target(&raid_target); 1681 } 1682 1683 module_init(dm_raid_init); 1684 module_exit(dm_raid_exit); 1685 1686 MODULE_DESCRIPTION(DM_NAME " raid4/5/6 target"); 1687 MODULE_ALIAS("dm-raid1"); 1688 MODULE_ALIAS("dm-raid10"); 1689 MODULE_ALIAS("dm-raid4"); 1690 MODULE_ALIAS("dm-raid5"); 1691 MODULE_ALIAS("dm-raid6"); 1692 MODULE_AUTHOR("Neil Brown <dm-devel@redhat.com>"); 1693 MODULE_LICENSE("GPL"); 1694