1/* 2 * Copyright (C) 2010-2011 Neil Brown 3 * Copyright (C) 2010-2014 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 21static bool devices_handle_discard_safely = false; 22 23/* 24 * The following flags are used by dm-raid.c to set up the array state. 25 * They must be cleared before md_run is called. 26 */ 27#define FirstUse 10 /* rdev flag */ 28 29struct raid_dev { 30 /* 31 * Two DM devices, one to hold metadata and one to hold the 32 * actual data/parity. The reason for this is to not confuse 33 * ti->len and give more flexibility in altering size and 34 * characteristics. 35 * 36 * While it is possible for this device to be associated 37 * with a different physical device than the data_dev, it 38 * is intended for it to be the same. 39 * |--------- Physical Device ---------| 40 * |- meta_dev -|------ data_dev ------| 41 */ 42 struct dm_dev *meta_dev; 43 struct dm_dev *data_dev; 44 struct md_rdev rdev; 45}; 46 47/* 48 * Flags for rs->print_flags field. 49 */ 50#define DMPF_SYNC 0x1 51#define DMPF_NOSYNC 0x2 52#define DMPF_REBUILD 0x4 53#define DMPF_DAEMON_SLEEP 0x8 54#define DMPF_MIN_RECOVERY_RATE 0x10 55#define DMPF_MAX_RECOVERY_RATE 0x20 56#define DMPF_MAX_WRITE_BEHIND 0x40 57#define DMPF_STRIPE_CACHE 0x80 58#define DMPF_REGION_SIZE 0x100 59#define DMPF_RAID10_COPIES 0x200 60#define DMPF_RAID10_FORMAT 0x400 61 62struct raid_set { 63 struct dm_target *ti; 64 65 uint32_t bitmap_loaded; 66 uint32_t print_flags; 67 68 struct mddev md; 69 struct raid_type *raid_type; 70 struct dm_target_callbacks callbacks; 71 72 struct raid_dev dev[0]; 73}; 74 75/* Supported raid types and properties. */ 76static struct raid_type { 77 const char *name; /* RAID algorithm. */ 78 const char *descr; /* Descriptor text for logging. */ 79 const unsigned parity_devs; /* # of parity devices. */ 80 const unsigned minimal_devs; /* minimal # of devices in set. */ 81 const unsigned level; /* RAID level. */ 82 const unsigned algorithm; /* RAID algorithm. */ 83} raid_types[] = { 84 {"raid1", "RAID1 (mirroring)", 0, 2, 1, 0 /* NONE */}, 85 {"raid10", "RAID10 (striped mirrors)", 0, 2, 10, UINT_MAX /* Varies */}, 86 {"raid4", "RAID4 (dedicated parity disk)", 1, 2, 5, ALGORITHM_PARITY_0}, 87 {"raid5_la", "RAID5 (left asymmetric)", 1, 2, 5, ALGORITHM_LEFT_ASYMMETRIC}, 88 {"raid5_ra", "RAID5 (right asymmetric)", 1, 2, 5, ALGORITHM_RIGHT_ASYMMETRIC}, 89 {"raid5_ls", "RAID5 (left symmetric)", 1, 2, 5, ALGORITHM_LEFT_SYMMETRIC}, 90 {"raid5_rs", "RAID5 (right symmetric)", 1, 2, 5, ALGORITHM_RIGHT_SYMMETRIC}, 91 {"raid6_zr", "RAID6 (zero restart)", 2, 4, 6, ALGORITHM_ROTATING_ZERO_RESTART}, 92 {"raid6_nr", "RAID6 (N restart)", 2, 4, 6, ALGORITHM_ROTATING_N_RESTART}, 93 {"raid6_nc", "RAID6 (N continue)", 2, 4, 6, ALGORITHM_ROTATING_N_CONTINUE} 94}; 95 96static char *raid10_md_layout_to_format(int layout) 97{ 98 /* 99 * Bit 16 and 17 stand for "offset" and "use_far_sets" 100 * Refer to MD's raid10.c for details 101 */ 102 if ((layout & 0x10000) && (layout & 0x20000)) 103 return "offset"; 104 105 if ((layout & 0xFF) > 1) 106 return "near"; 107 108 return "far"; 109} 110 111static unsigned raid10_md_layout_to_copies(int layout) 112{ 113 if ((layout & 0xFF) > 1) 114 return layout & 0xFF; 115 return (layout >> 8) & 0xFF; 116} 117 118static int raid10_format_to_md_layout(char *format, unsigned copies) 119{ 120 unsigned n = 1, f = 1; 121 122 if (!strcmp("near", format)) 123 n = copies; 124 else 125 f = copies; 126 127 if (!strcmp("offset", format)) 128 return 0x30000 | (f << 8) | n; 129 130 if (!strcmp("far", format)) 131 return 0x20000 | (f << 8) | n; 132 133 return (f << 8) | n; 134} 135 136static struct raid_type *get_raid_type(char *name) 137{ 138 int i; 139 140 for (i = 0; i < ARRAY_SIZE(raid_types); i++) 141 if (!strcmp(raid_types[i].name, name)) 142 return &raid_types[i]; 143 144 return NULL; 145} 146 147static struct raid_set *context_alloc(struct dm_target *ti, struct raid_type *raid_type, unsigned raid_devs) 148{ 149 unsigned i; 150 struct raid_set *rs; 151 152 if (raid_devs <= raid_type->parity_devs) { 153 ti->error = "Insufficient number of devices"; 154 return ERR_PTR(-EINVAL); 155 } 156 157 rs = kzalloc(sizeof(*rs) + raid_devs * sizeof(rs->dev[0]), GFP_KERNEL); 158 if (!rs) { 159 ti->error = "Cannot allocate raid context"; 160 return ERR_PTR(-ENOMEM); 161 } 162 163 mddev_init(&rs->md); 164 165 rs->ti = ti; 166 rs->raid_type = raid_type; 167 rs->md.raid_disks = raid_devs; 168 rs->md.level = raid_type->level; 169 rs->md.new_level = rs->md.level; 170 rs->md.layout = raid_type->algorithm; 171 rs->md.new_layout = rs->md.layout; 172 rs->md.delta_disks = 0; 173 rs->md.recovery_cp = 0; 174 175 for (i = 0; i < raid_devs; i++) 176 md_rdev_init(&rs->dev[i].rdev); 177 178 /* 179 * Remaining items to be initialized by further RAID params: 180 * rs->md.persistent 181 * rs->md.external 182 * rs->md.chunk_sectors 183 * rs->md.new_chunk_sectors 184 * rs->md.dev_sectors 185 */ 186 187 return rs; 188} 189 190static void context_free(struct raid_set *rs) 191{ 192 int i; 193 194 for (i = 0; i < rs->md.raid_disks; i++) { 195 if (rs->dev[i].meta_dev) 196 dm_put_device(rs->ti, rs->dev[i].meta_dev); 197 md_rdev_clear(&rs->dev[i].rdev); 198 if (rs->dev[i].data_dev) 199 dm_put_device(rs->ti, rs->dev[i].data_dev); 200 } 201 202 kfree(rs); 203} 204 205/* 206 * For every device we have two words 207 * <meta_dev>: meta device name or '-' if missing 208 * <data_dev>: data device name or '-' if missing 209 * 210 * The following are permitted: 211 * - - 212 * - <data_dev> 213 * <meta_dev> <data_dev> 214 * 215 * The following is not allowed: 216 * <meta_dev> - 217 * 218 * This code parses those words. If there is a failure, 219 * the caller must use context_free to unwind the operations. 220 */ 221static int dev_parms(struct raid_set *rs, char **argv) 222{ 223 int i; 224 int rebuild = 0; 225 int metadata_available = 0; 226 int ret = 0; 227 228 for (i = 0; i < rs->md.raid_disks; i++, argv += 2) { 229 rs->dev[i].rdev.raid_disk = i; 230 231 rs->dev[i].meta_dev = NULL; 232 rs->dev[i].data_dev = NULL; 233 234 /* 235 * There are no offsets, since there is a separate device 236 * for data and metadata. 237 */ 238 rs->dev[i].rdev.data_offset = 0; 239 rs->dev[i].rdev.mddev = &rs->md; 240 241 if (strcmp(argv[0], "-")) { 242 ret = dm_get_device(rs->ti, argv[0], 243 dm_table_get_mode(rs->ti->table), 244 &rs->dev[i].meta_dev); 245 rs->ti->error = "RAID metadata device lookup failure"; 246 if (ret) 247 return ret; 248 249 rs->dev[i].rdev.sb_page = alloc_page(GFP_KERNEL); 250 if (!rs->dev[i].rdev.sb_page) 251 return -ENOMEM; 252 } 253 254 if (!strcmp(argv[1], "-")) { 255 if (!test_bit(In_sync, &rs->dev[i].rdev.flags) && 256 (!rs->dev[i].rdev.recovery_offset)) { 257 rs->ti->error = "Drive designated for rebuild not specified"; 258 return -EINVAL; 259 } 260 261 rs->ti->error = "No data device supplied with metadata device"; 262 if (rs->dev[i].meta_dev) 263 return -EINVAL; 264 265 continue; 266 } 267 268 ret = dm_get_device(rs->ti, argv[1], 269 dm_table_get_mode(rs->ti->table), 270 &rs->dev[i].data_dev); 271 if (ret) { 272 rs->ti->error = "RAID device lookup failure"; 273 return ret; 274 } 275 276 if (rs->dev[i].meta_dev) { 277 metadata_available = 1; 278 rs->dev[i].rdev.meta_bdev = rs->dev[i].meta_dev->bdev; 279 } 280 rs->dev[i].rdev.bdev = rs->dev[i].data_dev->bdev; 281 list_add(&rs->dev[i].rdev.same_set, &rs->md.disks); 282 if (!test_bit(In_sync, &rs->dev[i].rdev.flags)) 283 rebuild++; 284 } 285 286 if (metadata_available) { 287 rs->md.external = 0; 288 rs->md.persistent = 1; 289 rs->md.major_version = 2; 290 } else if (rebuild && !rs->md.recovery_cp) { 291 /* 292 * Without metadata, we will not be able to tell if the array 293 * is in-sync or not - we must assume it is not. Therefore, 294 * it is impossible to rebuild a drive. 295 * 296 * Even if there is metadata, the on-disk information may 297 * indicate that the array is not in-sync and it will then 298 * fail at that time. 299 * 300 * User could specify 'nosync' option if desperate. 301 */ 302 DMERR("Unable to rebuild drive while array is not in-sync"); 303 rs->ti->error = "RAID device lookup failure"; 304 return -EINVAL; 305 } 306 307 return 0; 308} 309 310/* 311 * validate_region_size 312 * @rs 313 * @region_size: region size in sectors. If 0, pick a size (4MiB default). 314 * 315 * Set rs->md.bitmap_info.chunksize (which really refers to 'region size'). 316 * Ensure that (ti->len/region_size < 2^21) - required by MD bitmap. 317 * 318 * Returns: 0 on success, -EINVAL on failure. 319 */ 320static int validate_region_size(struct raid_set *rs, unsigned long region_size) 321{ 322 unsigned long min_region_size = rs->ti->len / (1 << 21); 323 324 if (!region_size) { 325 /* 326 * Choose a reasonable default. All figures in sectors. 327 */ 328 if (min_region_size > (1 << 13)) { 329 /* If not a power of 2, make it the next power of 2 */ 330 region_size = roundup_pow_of_two(min_region_size); 331 DMINFO("Choosing default region size of %lu sectors", 332 region_size); 333 } else { 334 DMINFO("Choosing default region size of 4MiB"); 335 region_size = 1 << 13; /* sectors */ 336 } 337 } else { 338 /* 339 * Validate user-supplied value. 340 */ 341 if (region_size > rs->ti->len) { 342 rs->ti->error = "Supplied region size is too large"; 343 return -EINVAL; 344 } 345 346 if (region_size < min_region_size) { 347 DMERR("Supplied region_size (%lu sectors) below minimum (%lu)", 348 region_size, min_region_size); 349 rs->ti->error = "Supplied region size is too small"; 350 return -EINVAL; 351 } 352 353 if (!is_power_of_2(region_size)) { 354 rs->ti->error = "Region size is not a power of 2"; 355 return -EINVAL; 356 } 357 358 if (region_size < rs->md.chunk_sectors) { 359 rs->ti->error = "Region size is smaller than the chunk size"; 360 return -EINVAL; 361 } 362 } 363 364 /* 365 * Convert sectors to bytes. 366 */ 367 rs->md.bitmap_info.chunksize = (region_size << 9); 368 369 return 0; 370} 371 372/* 373 * validate_raid_redundancy 374 * @rs 375 * 376 * Determine if there are enough devices in the array that haven't 377 * failed (or are being rebuilt) to form a usable array. 378 * 379 * Returns: 0 on success, -EINVAL on failure. 380 */ 381static int validate_raid_redundancy(struct raid_set *rs) 382{ 383 unsigned i, rebuild_cnt = 0; 384 unsigned rebuilds_per_group = 0, copies, d; 385 unsigned group_size, last_group_start; 386 387 for (i = 0; i < rs->md.raid_disks; i++) 388 if (!test_bit(In_sync, &rs->dev[i].rdev.flags) || 389 !rs->dev[i].rdev.sb_page) 390 rebuild_cnt++; 391 392 switch (rs->raid_type->level) { 393 case 1: 394 if (rebuild_cnt >= rs->md.raid_disks) 395 goto too_many; 396 break; 397 case 4: 398 case 5: 399 case 6: 400 if (rebuild_cnt > rs->raid_type->parity_devs) 401 goto too_many; 402 break; 403 case 10: 404 copies = raid10_md_layout_to_copies(rs->md.layout); 405 if (rebuild_cnt < copies) 406 break; 407 408 /* 409 * It is possible to have a higher rebuild count for RAID10, 410 * as long as the failed devices occur in different mirror 411 * groups (i.e. different stripes). 412 * 413 * When checking "near" format, make sure no adjacent devices 414 * have failed beyond what can be handled. In addition to the 415 * simple case where the number of devices is a multiple of the 416 * number of copies, we must also handle cases where the number 417 * of devices is not a multiple of the number of copies. 418 * E.g. dev1 dev2 dev3 dev4 dev5 419 * A A B B C 420 * C D D E E 421 */ 422 if (!strcmp("near", raid10_md_layout_to_format(rs->md.layout))) { 423 for (i = 0; i < rs->md.raid_disks * copies; i++) { 424 if (!(i % copies)) 425 rebuilds_per_group = 0; 426 d = i % rs->md.raid_disks; 427 if ((!rs->dev[d].rdev.sb_page || 428 !test_bit(In_sync, &rs->dev[d].rdev.flags)) && 429 (++rebuilds_per_group >= copies)) 430 goto too_many; 431 } 432 break; 433 } 434 435 /* 436 * When checking "far" and "offset" formats, we need to ensure 437 * that the device that holds its copy is not also dead or 438 * being rebuilt. (Note that "far" and "offset" formats only 439 * support two copies right now. These formats also only ever 440 * use the 'use_far_sets' variant.) 441 * 442 * This check is somewhat complicated by the need to account 443 * for arrays that are not a multiple of (far) copies. This 444 * results in the need to treat the last (potentially larger) 445 * set differently. 446 */ 447 group_size = (rs->md.raid_disks / copies); 448 last_group_start = (rs->md.raid_disks / group_size) - 1; 449 last_group_start *= group_size; 450 for (i = 0; i < rs->md.raid_disks; i++) { 451 if (!(i % copies) && !(i > last_group_start)) 452 rebuilds_per_group = 0; 453 if ((!rs->dev[i].rdev.sb_page || 454 !test_bit(In_sync, &rs->dev[i].rdev.flags)) && 455 (++rebuilds_per_group >= copies)) 456 goto too_many; 457 } 458 break; 459 default: 460 if (rebuild_cnt) 461 return -EINVAL; 462 } 463 464 return 0; 465 466too_many: 467 return -EINVAL; 468} 469 470/* 471 * Possible arguments are... 472 * <chunk_size> [optional_args] 473 * 474 * Argument definitions 475 * <chunk_size> The number of sectors per disk that 476 * will form the "stripe" 477 * [[no]sync] Force or prevent recovery of the 478 * entire array 479 * [devices_handle_discard_safely] Allow discards on RAID4/5/6; useful if RAID 480 * member device(s) properly support TRIM/UNMAP 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 */ 495static 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->print_flags |= DMPF_NOSYNC; 558 continue; 559 } 560 if (!strcasecmp(argv[i], "sync")) { 561 rs->md.recovery_cp = 0; 562 rs->print_flags |= DMPF_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->print_flags |= DMPF_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->print_flags |= DMPF_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->print_flags |= DMPF_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->print_flags |= DMPF_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->print_flags |= DMPF_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->print_flags |= DMPF_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->print_flags |= DMPF_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->print_flags |= DMPF_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->print_flags |= DMPF_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 > 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 737static 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 744static 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 756struct 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 788static 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 807static 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 */ 849static 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 898static 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 1028static 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 */ 1065static 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 * Enable/disable discard support on RAID set depending on 1154 * RAID level and discard properties of underlying RAID members. 1155 */ 1156static void configure_discard_support(struct dm_target *ti, struct raid_set *rs) 1157{ 1158 int i; 1159 bool raid456; 1160 1161 /* Assume discards not supported until after checks below. */ 1162 ti->discards_supported = false; 1163 1164 /* RAID level 4,5,6 require discard_zeroes_data for data integrity! */ 1165 raid456 = (rs->md.level == 4 || rs->md.level == 5 || rs->md.level == 6); 1166 1167 for (i = 0; i < rs->md.raid_disks; i++) { 1168 struct request_queue *q; 1169 1170 if (!rs->dev[i].rdev.bdev) 1171 continue; 1172 1173 q = bdev_get_queue(rs->dev[i].rdev.bdev); 1174 if (!q || !blk_queue_discard(q)) 1175 return; 1176 1177 if (raid456) { 1178 if (!q->limits.discard_zeroes_data) 1179 return; 1180 if (!devices_handle_discard_safely) { 1181 DMERR("raid456 discard support disabled due to discard_zeroes_data uncertainty."); 1182 DMERR("Set dm-raid.devices_handle_discard_safely=Y to override."); 1183 return; 1184 } 1185 } 1186 } 1187 1188 /* All RAID members properly support discards */ 1189 ti->discards_supported = true; 1190 1191 /* 1192 * RAID1 and RAID10 personalities require bio splitting, 1193 * RAID0/4/5/6 don't and process large discard bios properly. 1194 */ 1195 ti->split_discard_bios = !!(rs->md.level == 1 || rs->md.level == 10); 1196 ti->num_discard_bios = 1; 1197} 1198 1199/* 1200 * Construct a RAID4/5/6 mapping: 1201 * Args: 1202 * <raid_type> <#raid_params> <raid_params> \ 1203 * <#raid_devs> { <meta_dev1> <dev1> .. <meta_devN> <devN> } 1204 * 1205 * <raid_params> varies by <raid_type>. See 'parse_raid_params' for 1206 * details on possible <raid_params>. 1207 */ 1208static int raid_ctr(struct dm_target *ti, unsigned argc, char **argv) 1209{ 1210 int ret; 1211 struct raid_type *rt; 1212 unsigned long num_raid_params, num_raid_devs; 1213 struct raid_set *rs = NULL; 1214 1215 /* Must have at least <raid_type> <#raid_params> */ 1216 if (argc < 2) { 1217 ti->error = "Too few arguments"; 1218 return -EINVAL; 1219 } 1220 1221 /* raid type */ 1222 rt = get_raid_type(argv[0]); 1223 if (!rt) { 1224 ti->error = "Unrecognised raid_type"; 1225 return -EINVAL; 1226 } 1227 argc--; 1228 argv++; 1229 1230 /* number of RAID parameters */ 1231 if (kstrtoul(argv[0], 10, &num_raid_params) < 0) { 1232 ti->error = "Cannot understand number of RAID parameters"; 1233 return -EINVAL; 1234 } 1235 argc--; 1236 argv++; 1237 1238 /* Skip over RAID params for now and find out # of devices */ 1239 if (num_raid_params >= argc) { 1240 ti->error = "Arguments do not agree with counts given"; 1241 return -EINVAL; 1242 } 1243 1244 if ((kstrtoul(argv[num_raid_params], 10, &num_raid_devs) < 0) || 1245 (num_raid_devs >= INT_MAX)) { 1246 ti->error = "Cannot understand number of raid devices"; 1247 return -EINVAL; 1248 } 1249 1250 argc -= num_raid_params + 1; /* +1: we already have num_raid_devs */ 1251 if (argc != (num_raid_devs * 2)) { 1252 ti->error = "Supplied RAID devices does not match the count given"; 1253 return -EINVAL; 1254 } 1255 1256 rs = context_alloc(ti, rt, (unsigned)num_raid_devs); 1257 if (IS_ERR(rs)) 1258 return PTR_ERR(rs); 1259 1260 ret = parse_raid_params(rs, argv, (unsigned)num_raid_params); 1261 if (ret) 1262 goto bad; 1263 1264 argv += num_raid_params + 1; 1265 1266 ret = dev_parms(rs, argv); 1267 if (ret) 1268 goto bad; 1269 1270 rs->md.sync_super = super_sync; 1271 ret = analyse_superblocks(ti, rs); 1272 if (ret) 1273 goto bad; 1274 1275 INIT_WORK(&rs->md.event_work, do_table_event); 1276 ti->private = rs; 1277 ti->num_flush_bios = 1; 1278 1279 /* 1280 * Disable/enable discard support on RAID set. 1281 */ 1282 configure_discard_support(ti, rs); 1283 1284 mutex_lock(&rs->md.reconfig_mutex); 1285 ret = md_run(&rs->md); 1286 rs->md.in_sync = 0; /* Assume already marked dirty */ 1287 mutex_unlock(&rs->md.reconfig_mutex); 1288 1289 if (ret) { 1290 ti->error = "Fail to run raid array"; 1291 goto bad; 1292 } 1293 1294 if (ti->len != rs->md.array_sectors) { 1295 ti->error = "Array size does not match requested target length"; 1296 ret = -EINVAL; 1297 goto size_mismatch; 1298 } 1299 rs->callbacks.congested_fn = raid_is_congested; 1300 dm_table_add_target_callbacks(ti->table, &rs->callbacks); 1301 1302 mddev_suspend(&rs->md); 1303 return 0; 1304 1305size_mismatch: 1306 md_stop(&rs->md); 1307bad: 1308 context_free(rs); 1309 1310 return ret; 1311} 1312 1313static void raid_dtr(struct dm_target *ti) 1314{ 1315 struct raid_set *rs = ti->private; 1316 1317 list_del_init(&rs->callbacks.list); 1318 md_stop(&rs->md); 1319 context_free(rs); 1320} 1321 1322static int raid_map(struct dm_target *ti, struct bio *bio) 1323{ 1324 struct raid_set *rs = ti->private; 1325 struct mddev *mddev = &rs->md; 1326 1327 mddev->pers->make_request(mddev, bio); 1328 1329 return DM_MAPIO_SUBMITTED; 1330} 1331 1332static const char *decipher_sync_action(struct mddev *mddev) 1333{ 1334 if (test_bit(MD_RECOVERY_FROZEN, &mddev->recovery)) 1335 return "frozen"; 1336 1337 if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) || 1338 (!mddev->ro && test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))) { 1339 if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)) 1340 return "reshape"; 1341 1342 if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) { 1343 if (!test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) 1344 return "resync"; 1345 else if (test_bit(MD_RECOVERY_CHECK, &mddev->recovery)) 1346 return "check"; 1347 return "repair"; 1348 } 1349 1350 if (test_bit(MD_RECOVERY_RECOVER, &mddev->recovery)) 1351 return "recover"; 1352 } 1353 1354 return "idle"; 1355} 1356 1357static void raid_status(struct dm_target *ti, status_type_t type, 1358 unsigned status_flags, char *result, unsigned maxlen) 1359{ 1360 struct raid_set *rs = ti->private; 1361 unsigned raid_param_cnt = 1; /* at least 1 for chunksize */ 1362 unsigned sz = 0; 1363 int i, array_in_sync = 0; 1364 sector_t sync; 1365 1366 switch (type) { 1367 case STATUSTYPE_INFO: 1368 DMEMIT("%s %d ", rs->raid_type->name, rs->md.raid_disks); 1369 1370 if (test_bit(MD_RECOVERY_RUNNING, &rs->md.recovery)) 1371 sync = rs->md.curr_resync_completed; 1372 else 1373 sync = rs->md.recovery_cp; 1374 1375 if (sync >= rs->md.resync_max_sectors) { 1376 /* 1377 * Sync complete. 1378 */ 1379 array_in_sync = 1; 1380 sync = rs->md.resync_max_sectors; 1381 } else if (test_bit(MD_RECOVERY_REQUESTED, &rs->md.recovery)) { 1382 /* 1383 * If "check" or "repair" is occurring, the array has 1384 * undergone and initial sync and the health characters 1385 * should not be 'a' anymore. 1386 */ 1387 array_in_sync = 1; 1388 } else { 1389 /* 1390 * The array may be doing an initial sync, or it may 1391 * be rebuilding individual components. If all the 1392 * devices are In_sync, then it is the array that is 1393 * being initialized. 1394 */ 1395 for (i = 0; i < rs->md.raid_disks; i++) 1396 if (!test_bit(In_sync, &rs->dev[i].rdev.flags)) 1397 array_in_sync = 1; 1398 } 1399 1400 /* 1401 * Status characters: 1402 * 'D' = Dead/Failed device 1403 * 'a' = Alive but not in-sync 1404 * 'A' = Alive and in-sync 1405 */ 1406 for (i = 0; i < rs->md.raid_disks; i++) { 1407 if (test_bit(Faulty, &rs->dev[i].rdev.flags)) 1408 DMEMIT("D"); 1409 else if (!array_in_sync || 1410 !test_bit(In_sync, &rs->dev[i].rdev.flags)) 1411 DMEMIT("a"); 1412 else 1413 DMEMIT("A"); 1414 } 1415 1416 /* 1417 * In-sync ratio: 1418 * The in-sync ratio shows the progress of: 1419 * - Initializing the array 1420 * - Rebuilding a subset of devices of the array 1421 * The user can distinguish between the two by referring 1422 * to the status characters. 1423 */ 1424 DMEMIT(" %llu/%llu", 1425 (unsigned long long) sync, 1426 (unsigned long long) rs->md.resync_max_sectors); 1427 1428 /* 1429 * Sync action: 1430 * See Documentation/device-mapper/dm-raid.c for 1431 * information on each of these states. 1432 */ 1433 DMEMIT(" %s", decipher_sync_action(&rs->md)); 1434 1435 /* 1436 * resync_mismatches/mismatch_cnt 1437 * This field shows the number of discrepancies found when 1438 * performing a "check" of the array. 1439 */ 1440 DMEMIT(" %llu", 1441 (strcmp(rs->md.last_sync_action, "check")) ? 0 : 1442 (unsigned long long) 1443 atomic64_read(&rs->md.resync_mismatches)); 1444 break; 1445 case STATUSTYPE_TABLE: 1446 /* The string you would use to construct this array */ 1447 for (i = 0; i < rs->md.raid_disks; i++) { 1448 if ((rs->print_flags & DMPF_REBUILD) && 1449 rs->dev[i].data_dev && 1450 !test_bit(In_sync, &rs->dev[i].rdev.flags)) 1451 raid_param_cnt += 2; /* for rebuilds */ 1452 if (rs->dev[i].data_dev && 1453 test_bit(WriteMostly, &rs->dev[i].rdev.flags)) 1454 raid_param_cnt += 2; 1455 } 1456 1457 raid_param_cnt += (hweight32(rs->print_flags & ~DMPF_REBUILD) * 2); 1458 if (rs->print_flags & (DMPF_SYNC | DMPF_NOSYNC)) 1459 raid_param_cnt--; 1460 1461 DMEMIT("%s %u %u", rs->raid_type->name, 1462 raid_param_cnt, rs->md.chunk_sectors); 1463 1464 if ((rs->print_flags & DMPF_SYNC) && 1465 (rs->md.recovery_cp == MaxSector)) 1466 DMEMIT(" sync"); 1467 if (rs->print_flags & DMPF_NOSYNC) 1468 DMEMIT(" nosync"); 1469 1470 for (i = 0; i < rs->md.raid_disks; i++) 1471 if ((rs->print_flags & DMPF_REBUILD) && 1472 rs->dev[i].data_dev && 1473 !test_bit(In_sync, &rs->dev[i].rdev.flags)) 1474 DMEMIT(" rebuild %u", i); 1475 1476 if (rs->print_flags & DMPF_DAEMON_SLEEP) 1477 DMEMIT(" daemon_sleep %lu", 1478 rs->md.bitmap_info.daemon_sleep); 1479 1480 if (rs->print_flags & DMPF_MIN_RECOVERY_RATE) 1481 DMEMIT(" min_recovery_rate %d", rs->md.sync_speed_min); 1482 1483 if (rs->print_flags & DMPF_MAX_RECOVERY_RATE) 1484 DMEMIT(" max_recovery_rate %d", rs->md.sync_speed_max); 1485 1486 for (i = 0; i < rs->md.raid_disks; i++) 1487 if (rs->dev[i].data_dev && 1488 test_bit(WriteMostly, &rs->dev[i].rdev.flags)) 1489 DMEMIT(" write_mostly %u", i); 1490 1491 if (rs->print_flags & DMPF_MAX_WRITE_BEHIND) 1492 DMEMIT(" max_write_behind %lu", 1493 rs->md.bitmap_info.max_write_behind); 1494 1495 if (rs->print_flags & DMPF_STRIPE_CACHE) { 1496 struct r5conf *conf = rs->md.private; 1497 1498 /* convert from kiB to sectors */ 1499 DMEMIT(" stripe_cache %d", 1500 conf ? conf->max_nr_stripes * 2 : 0); 1501 } 1502 1503 if (rs->print_flags & DMPF_REGION_SIZE) 1504 DMEMIT(" region_size %lu", 1505 rs->md.bitmap_info.chunksize >> 9); 1506 1507 if (rs->print_flags & DMPF_RAID10_COPIES) 1508 DMEMIT(" raid10_copies %u", 1509 raid10_md_layout_to_copies(rs->md.layout)); 1510 1511 if (rs->print_flags & DMPF_RAID10_FORMAT) 1512 DMEMIT(" raid10_format %s", 1513 raid10_md_layout_to_format(rs->md.layout)); 1514 1515 DMEMIT(" %d", rs->md.raid_disks); 1516 for (i = 0; i < rs->md.raid_disks; i++) { 1517 if (rs->dev[i].meta_dev) 1518 DMEMIT(" %s", rs->dev[i].meta_dev->name); 1519 else 1520 DMEMIT(" -"); 1521 1522 if (rs->dev[i].data_dev) 1523 DMEMIT(" %s", rs->dev[i].data_dev->name); 1524 else 1525 DMEMIT(" -"); 1526 } 1527 } 1528} 1529 1530static int raid_message(struct dm_target *ti, unsigned argc, char **argv) 1531{ 1532 struct raid_set *rs = ti->private; 1533 struct mddev *mddev = &rs->md; 1534 1535 if (!strcasecmp(argv[0], "reshape")) { 1536 DMERR("Reshape not supported."); 1537 return -EINVAL; 1538 } 1539 1540 if (!mddev->pers || !mddev->pers->sync_request) 1541 return -EINVAL; 1542 1543 if (!strcasecmp(argv[0], "frozen")) 1544 set_bit(MD_RECOVERY_FROZEN, &mddev->recovery); 1545 else 1546 clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery); 1547 1548 if (!strcasecmp(argv[0], "idle") || !strcasecmp(argv[0], "frozen")) { 1549 if (mddev->sync_thread) { 1550 set_bit(MD_RECOVERY_INTR, &mddev->recovery); 1551 md_reap_sync_thread(mddev); 1552 } 1553 } else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) || 1554 test_bit(MD_RECOVERY_NEEDED, &mddev->recovery)) 1555 return -EBUSY; 1556 else if (!strcasecmp(argv[0], "resync")) 1557 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); 1558 else if (!strcasecmp(argv[0], "recover")) { 1559 set_bit(MD_RECOVERY_RECOVER, &mddev->recovery); 1560 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); 1561 } else { 1562 if (!strcasecmp(argv[0], "check")) 1563 set_bit(MD_RECOVERY_CHECK, &mddev->recovery); 1564 else if (!!strcasecmp(argv[0], "repair")) 1565 return -EINVAL; 1566 set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery); 1567 set_bit(MD_RECOVERY_SYNC, &mddev->recovery); 1568 } 1569 if (mddev->ro == 2) { 1570 /* A write to sync_action is enough to justify 1571 * canceling read-auto mode 1572 */ 1573 mddev->ro = 0; 1574 if (!mddev->suspended) 1575 md_wakeup_thread(mddev->sync_thread); 1576 } 1577 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); 1578 if (!mddev->suspended) 1579 md_wakeup_thread(mddev->thread); 1580 1581 return 0; 1582} 1583 1584static int raid_iterate_devices(struct dm_target *ti, 1585 iterate_devices_callout_fn fn, void *data) 1586{ 1587 struct raid_set *rs = ti->private; 1588 unsigned i; 1589 int ret = 0; 1590 1591 for (i = 0; !ret && i < rs->md.raid_disks; i++) 1592 if (rs->dev[i].data_dev) 1593 ret = fn(ti, 1594 rs->dev[i].data_dev, 1595 0, /* No offset on data devs */ 1596 rs->md.dev_sectors, 1597 data); 1598 1599 return ret; 1600} 1601 1602static void raid_io_hints(struct dm_target *ti, struct queue_limits *limits) 1603{ 1604 struct raid_set *rs = ti->private; 1605 unsigned chunk_size = rs->md.chunk_sectors << 9; 1606 struct r5conf *conf = rs->md.private; 1607 1608 blk_limits_io_min(limits, chunk_size); 1609 blk_limits_io_opt(limits, chunk_size * (conf->raid_disks - conf->max_degraded)); 1610} 1611 1612static void raid_presuspend(struct dm_target *ti) 1613{ 1614 struct raid_set *rs = ti->private; 1615 1616 md_stop_writes(&rs->md); 1617} 1618 1619static void raid_postsuspend(struct dm_target *ti) 1620{ 1621 struct raid_set *rs = ti->private; 1622 1623 mddev_suspend(&rs->md); 1624} 1625 1626static void attempt_restore_of_faulty_devices(struct raid_set *rs) 1627{ 1628 int i; 1629 uint64_t failed_devices, cleared_failed_devices = 0; 1630 unsigned long flags; 1631 struct dm_raid_superblock *sb; 1632 struct md_rdev *r; 1633 1634 for (i = 0; i < rs->md.raid_disks; i++) { 1635 r = &rs->dev[i].rdev; 1636 if (test_bit(Faulty, &r->flags) && r->sb_page && 1637 sync_page_io(r, 0, r->sb_size, r->sb_page, READ, 1)) { 1638 DMINFO("Faulty %s device #%d has readable super block." 1639 " Attempting to revive it.", 1640 rs->raid_type->name, i); 1641 1642 /* 1643 * Faulty bit may be set, but sometimes the array can 1644 * be suspended before the personalities can respond 1645 * by removing the device from the array (i.e. calling 1646 * 'hot_remove_disk'). If they haven't yet removed 1647 * the failed device, its 'raid_disk' number will be 1648 * '>= 0' - meaning we must call this function 1649 * ourselves. 1650 */ 1651 if ((r->raid_disk >= 0) && 1652 (r->mddev->pers->hot_remove_disk(r->mddev, r) != 0)) 1653 /* Failed to revive this device, try next */ 1654 continue; 1655 1656 r->raid_disk = i; 1657 r->saved_raid_disk = i; 1658 flags = r->flags; 1659 clear_bit(Faulty, &r->flags); 1660 clear_bit(WriteErrorSeen, &r->flags); 1661 clear_bit(In_sync, &r->flags); 1662 if (r->mddev->pers->hot_add_disk(r->mddev, r)) { 1663 r->raid_disk = -1; 1664 r->saved_raid_disk = -1; 1665 r->flags = flags; 1666 } else { 1667 r->recovery_offset = 0; 1668 cleared_failed_devices |= 1 << i; 1669 } 1670 } 1671 } 1672 if (cleared_failed_devices) { 1673 rdev_for_each(r, &rs->md) { 1674 sb = page_address(r->sb_page); 1675 failed_devices = le64_to_cpu(sb->failed_devices); 1676 failed_devices &= ~cleared_failed_devices; 1677 sb->failed_devices = cpu_to_le64(failed_devices); 1678 } 1679 } 1680} 1681 1682static void raid_resume(struct dm_target *ti) 1683{ 1684 struct raid_set *rs = ti->private; 1685 1686 set_bit(MD_CHANGE_DEVS, &rs->md.flags); 1687 if (!rs->bitmap_loaded) { 1688 bitmap_load(&rs->md); 1689 rs->bitmap_loaded = 1; 1690 } else { 1691 /* 1692 * A secondary resume while the device is active. 1693 * Take this opportunity to check whether any failed 1694 * devices are reachable again. 1695 */ 1696 attempt_restore_of_faulty_devices(rs); 1697 } 1698 1699 clear_bit(MD_RECOVERY_FROZEN, &rs->md.recovery); 1700 mddev_resume(&rs->md); 1701} 1702 1703static struct target_type raid_target = { 1704 .name = "raid", 1705 .version = {1, 6, 0}, 1706 .module = THIS_MODULE, 1707 .ctr = raid_ctr, 1708 .dtr = raid_dtr, 1709 .map = raid_map, 1710 .status = raid_status, 1711 .message = raid_message, 1712 .iterate_devices = raid_iterate_devices, 1713 .io_hints = raid_io_hints, 1714 .presuspend = raid_presuspend, 1715 .postsuspend = raid_postsuspend, 1716 .resume = raid_resume, 1717}; 1718 1719static int __init dm_raid_init(void) 1720{ 1721 DMINFO("Loading target version %u.%u.%u", 1722 raid_target.version[0], 1723 raid_target.version[1], 1724 raid_target.version[2]); 1725 return dm_register_target(&raid_target); 1726} 1727 1728static void __exit dm_raid_exit(void) 1729{ 1730 dm_unregister_target(&raid_target); 1731} 1732 1733module_init(dm_raid_init); 1734module_exit(dm_raid_exit); 1735 1736module_param(devices_handle_discard_safely, bool, 0644); 1737MODULE_PARM_DESC(devices_handle_discard_safely, 1738 "Set to Y if all devices in each array reliably return zeroes on reads from discarded regions"); 1739 1740MODULE_DESCRIPTION(DM_NAME " raid4/5/6 target"); 1741MODULE_ALIAS("dm-raid1"); 1742MODULE_ALIAS("dm-raid10"); 1743MODULE_ALIAS("dm-raid4"); 1744MODULE_ALIAS("dm-raid5"); 1745MODULE_ALIAS("dm-raid6"); 1746MODULE_AUTHOR("Neil Brown <dm-devel@redhat.com>"); 1747MODULE_LICENSE("GPL"); 1748