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 unsigned raid10_md_layout_to_copies(int layout) 95 { 96 return layout & 0xFF; 97 } 98 99 static int raid10_format_to_md_layout(char *format, unsigned copies) 100 { 101 /* 1 "far" copy, and 'copies' "near" copies */ 102 return (1 << 8) | (copies & 0xFF); 103 } 104 105 static struct raid_type *get_raid_type(char *name) 106 { 107 int i; 108 109 for (i = 0; i < ARRAY_SIZE(raid_types); i++) 110 if (!strcmp(raid_types[i].name, name)) 111 return &raid_types[i]; 112 113 return NULL; 114 } 115 116 static struct raid_set *context_alloc(struct dm_target *ti, struct raid_type *raid_type, unsigned raid_devs) 117 { 118 unsigned i; 119 struct raid_set *rs; 120 121 if (raid_devs <= raid_type->parity_devs) { 122 ti->error = "Insufficient number of devices"; 123 return ERR_PTR(-EINVAL); 124 } 125 126 rs = kzalloc(sizeof(*rs) + raid_devs * sizeof(rs->dev[0]), GFP_KERNEL); 127 if (!rs) { 128 ti->error = "Cannot allocate raid context"; 129 return ERR_PTR(-ENOMEM); 130 } 131 132 mddev_init(&rs->md); 133 134 rs->ti = ti; 135 rs->raid_type = raid_type; 136 rs->md.raid_disks = raid_devs; 137 rs->md.level = raid_type->level; 138 rs->md.new_level = rs->md.level; 139 rs->md.layout = raid_type->algorithm; 140 rs->md.new_layout = rs->md.layout; 141 rs->md.delta_disks = 0; 142 rs->md.recovery_cp = 0; 143 144 for (i = 0; i < raid_devs; i++) 145 md_rdev_init(&rs->dev[i].rdev); 146 147 /* 148 * Remaining items to be initialized by further RAID params: 149 * rs->md.persistent 150 * rs->md.external 151 * rs->md.chunk_sectors 152 * rs->md.new_chunk_sectors 153 * rs->md.dev_sectors 154 */ 155 156 return rs; 157 } 158 159 static void context_free(struct raid_set *rs) 160 { 161 int i; 162 163 for (i = 0; i < rs->md.raid_disks; i++) { 164 if (rs->dev[i].meta_dev) 165 dm_put_device(rs->ti, rs->dev[i].meta_dev); 166 md_rdev_clear(&rs->dev[i].rdev); 167 if (rs->dev[i].data_dev) 168 dm_put_device(rs->ti, rs->dev[i].data_dev); 169 } 170 171 kfree(rs); 172 } 173 174 /* 175 * For every device we have two words 176 * <meta_dev>: meta device name or '-' if missing 177 * <data_dev>: data device name or '-' if missing 178 * 179 * The following are permitted: 180 * - - 181 * - <data_dev> 182 * <meta_dev> <data_dev> 183 * 184 * The following is not allowed: 185 * <meta_dev> - 186 * 187 * This code parses those words. If there is a failure, 188 * the caller must use context_free to unwind the operations. 189 */ 190 static int dev_parms(struct raid_set *rs, char **argv) 191 { 192 int i; 193 int rebuild = 0; 194 int metadata_available = 0; 195 int ret = 0; 196 197 for (i = 0; i < rs->md.raid_disks; i++, argv += 2) { 198 rs->dev[i].rdev.raid_disk = i; 199 200 rs->dev[i].meta_dev = NULL; 201 rs->dev[i].data_dev = NULL; 202 203 /* 204 * There are no offsets, since there is a separate device 205 * for data and metadata. 206 */ 207 rs->dev[i].rdev.data_offset = 0; 208 rs->dev[i].rdev.mddev = &rs->md; 209 210 if (strcmp(argv[0], "-")) { 211 ret = dm_get_device(rs->ti, argv[0], 212 dm_table_get_mode(rs->ti->table), 213 &rs->dev[i].meta_dev); 214 rs->ti->error = "RAID metadata device lookup failure"; 215 if (ret) 216 return ret; 217 218 rs->dev[i].rdev.sb_page = alloc_page(GFP_KERNEL); 219 if (!rs->dev[i].rdev.sb_page) 220 return -ENOMEM; 221 } 222 223 if (!strcmp(argv[1], "-")) { 224 if (!test_bit(In_sync, &rs->dev[i].rdev.flags) && 225 (!rs->dev[i].rdev.recovery_offset)) { 226 rs->ti->error = "Drive designated for rebuild not specified"; 227 return -EINVAL; 228 } 229 230 rs->ti->error = "No data device supplied with metadata device"; 231 if (rs->dev[i].meta_dev) 232 return -EINVAL; 233 234 continue; 235 } 236 237 ret = dm_get_device(rs->ti, argv[1], 238 dm_table_get_mode(rs->ti->table), 239 &rs->dev[i].data_dev); 240 if (ret) { 241 rs->ti->error = "RAID device lookup failure"; 242 return ret; 243 } 244 245 if (rs->dev[i].meta_dev) { 246 metadata_available = 1; 247 rs->dev[i].rdev.meta_bdev = rs->dev[i].meta_dev->bdev; 248 } 249 rs->dev[i].rdev.bdev = rs->dev[i].data_dev->bdev; 250 list_add(&rs->dev[i].rdev.same_set, &rs->md.disks); 251 if (!test_bit(In_sync, &rs->dev[i].rdev.flags)) 252 rebuild++; 253 } 254 255 if (metadata_available) { 256 rs->md.external = 0; 257 rs->md.persistent = 1; 258 rs->md.major_version = 2; 259 } else if (rebuild && !rs->md.recovery_cp) { 260 /* 261 * Without metadata, we will not be able to tell if the array 262 * is in-sync or not - we must assume it is not. Therefore, 263 * it is impossible to rebuild a drive. 264 * 265 * Even if there is metadata, the on-disk information may 266 * indicate that the array is not in-sync and it will then 267 * fail at that time. 268 * 269 * User could specify 'nosync' option if desperate. 270 */ 271 DMERR("Unable to rebuild drive while array is not in-sync"); 272 rs->ti->error = "RAID device lookup failure"; 273 return -EINVAL; 274 } 275 276 return 0; 277 } 278 279 /* 280 * validate_region_size 281 * @rs 282 * @region_size: region size in sectors. If 0, pick a size (4MiB default). 283 * 284 * Set rs->md.bitmap_info.chunksize (which really refers to 'region size'). 285 * Ensure that (ti->len/region_size < 2^21) - required by MD bitmap. 286 * 287 * Returns: 0 on success, -EINVAL on failure. 288 */ 289 static int validate_region_size(struct raid_set *rs, unsigned long region_size) 290 { 291 unsigned long min_region_size = rs->ti->len / (1 << 21); 292 293 if (!region_size) { 294 /* 295 * Choose a reasonable default. All figures in sectors. 296 */ 297 if (min_region_size > (1 << 13)) { 298 DMINFO("Choosing default region size of %lu sectors", 299 region_size); 300 region_size = min_region_size; 301 } else { 302 DMINFO("Choosing default region size of 4MiB"); 303 region_size = 1 << 13; /* sectors */ 304 } 305 } else { 306 /* 307 * Validate user-supplied value. 308 */ 309 if (region_size > rs->ti->len) { 310 rs->ti->error = "Supplied region size is too large"; 311 return -EINVAL; 312 } 313 314 if (region_size < min_region_size) { 315 DMERR("Supplied region_size (%lu sectors) below minimum (%lu)", 316 region_size, min_region_size); 317 rs->ti->error = "Supplied region size is too small"; 318 return -EINVAL; 319 } 320 321 if (!is_power_of_2(region_size)) { 322 rs->ti->error = "Region size is not a power of 2"; 323 return -EINVAL; 324 } 325 326 if (region_size < rs->md.chunk_sectors) { 327 rs->ti->error = "Region size is smaller than the chunk size"; 328 return -EINVAL; 329 } 330 } 331 332 /* 333 * Convert sectors to bytes. 334 */ 335 rs->md.bitmap_info.chunksize = (region_size << 9); 336 337 return 0; 338 } 339 340 /* 341 * validate_rebuild_devices 342 * @rs 343 * 344 * Determine if the devices specified for rebuild can result in a valid 345 * usable array that is capable of rebuilding the given devices. 346 * 347 * Returns: 0 on success, -EINVAL on failure. 348 */ 349 static int validate_rebuild_devices(struct raid_set *rs) 350 { 351 unsigned i, rebuild_cnt = 0; 352 unsigned rebuilds_per_group, copies, d; 353 354 if (!(rs->print_flags & DMPF_REBUILD)) 355 return 0; 356 357 for (i = 0; i < rs->md.raid_disks; i++) 358 if (!test_bit(In_sync, &rs->dev[i].rdev.flags)) 359 rebuild_cnt++; 360 361 switch (rs->raid_type->level) { 362 case 1: 363 if (rebuild_cnt >= rs->md.raid_disks) 364 goto too_many; 365 break; 366 case 4: 367 case 5: 368 case 6: 369 if (rebuild_cnt > rs->raid_type->parity_devs) 370 goto too_many; 371 break; 372 case 10: 373 copies = raid10_md_layout_to_copies(rs->md.layout); 374 if (rebuild_cnt < copies) 375 break; 376 377 /* 378 * It is possible to have a higher rebuild count for RAID10, 379 * as long as the failed devices occur in different mirror 380 * groups (i.e. different stripes). 381 * 382 * Right now, we only allow for "near" copies. When other 383 * formats are added, we will have to check those too. 384 * 385 * When checking "near" format, make sure no adjacent devices 386 * have failed beyond what can be handled. In addition to the 387 * simple case where the number of devices is a multiple of the 388 * number of copies, we must also handle cases where the number 389 * of devices is not a multiple of the number of copies. 390 * E.g. dev1 dev2 dev3 dev4 dev5 391 * A A B B C 392 * C D D E E 393 */ 394 rebuilds_per_group = 0; 395 for (i = 0; i < rs->md.raid_disks * copies; i++) { 396 d = i % rs->md.raid_disks; 397 if (!test_bit(In_sync, &rs->dev[d].rdev.flags) && 398 (++rebuilds_per_group >= copies)) 399 goto too_many; 400 if (!((i + 1) % copies)) 401 rebuilds_per_group = 0; 402 } 403 break; 404 default: 405 DMERR("The rebuild parameter is not supported for %s", 406 rs->raid_type->name); 407 rs->ti->error = "Rebuild not supported for this RAID type"; 408 return -EINVAL; 409 } 410 411 return 0; 412 413 too_many: 414 rs->ti->error = "Too many rebuild devices specified"; 415 return -EINVAL; 416 } 417 418 /* 419 * Possible arguments are... 420 * <chunk_size> [optional_args] 421 * 422 * Argument definitions 423 * <chunk_size> The number of sectors per disk that 424 * will form the "stripe" 425 * [[no]sync] Force or prevent recovery of the 426 * entire array 427 * [rebuild <idx>] Rebuild the drive indicated by the index 428 * [daemon_sleep <ms>] Time between bitmap daemon work to 429 * clear bits 430 * [min_recovery_rate <kB/sec/disk>] Throttle RAID initialization 431 * [max_recovery_rate <kB/sec/disk>] Throttle RAID initialization 432 * [write_mostly <idx>] Indicate a write mostly drive via index 433 * [max_write_behind <sectors>] See '-write-behind=' (man mdadm) 434 * [stripe_cache <sectors>] Stripe cache size for higher RAIDs 435 * [region_size <sectors>] Defines granularity of bitmap 436 * 437 * RAID10-only options: 438 * [raid10_copies <# copies>] Number of copies. (Default: 2) 439 * [raid10_format <near>] Layout algorithm. (Default: near) 440 */ 441 static int parse_raid_params(struct raid_set *rs, char **argv, 442 unsigned num_raid_params) 443 { 444 char *raid10_format = "near"; 445 unsigned raid10_copies = 2; 446 unsigned i; 447 unsigned long value, region_size = 0; 448 sector_t sectors_per_dev = rs->ti->len; 449 sector_t max_io_len; 450 char *key; 451 452 /* 453 * First, parse the in-order required arguments 454 * "chunk_size" is the only argument of this type. 455 */ 456 if ((strict_strtoul(argv[0], 10, &value) < 0)) { 457 rs->ti->error = "Bad chunk size"; 458 return -EINVAL; 459 } else if (rs->raid_type->level == 1) { 460 if (value) 461 DMERR("Ignoring chunk size parameter for RAID 1"); 462 value = 0; 463 } else if (!is_power_of_2(value)) { 464 rs->ti->error = "Chunk size must be a power of 2"; 465 return -EINVAL; 466 } else if (value < 8) { 467 rs->ti->error = "Chunk size value is too small"; 468 return -EINVAL; 469 } 470 471 rs->md.new_chunk_sectors = rs->md.chunk_sectors = value; 472 argv++; 473 num_raid_params--; 474 475 /* 476 * We set each individual device as In_sync with a completed 477 * 'recovery_offset'. If there has been a device failure or 478 * replacement then one of the following cases applies: 479 * 480 * 1) User specifies 'rebuild'. 481 * - Device is reset when param is read. 482 * 2) A new device is supplied. 483 * - No matching superblock found, resets device. 484 * 3) Device failure was transient and returns on reload. 485 * - Failure noticed, resets device for bitmap replay. 486 * 4) Device hadn't completed recovery after previous failure. 487 * - Superblock is read and overrides recovery_offset. 488 * 489 * What is found in the superblocks of the devices is always 490 * authoritative, unless 'rebuild' or '[no]sync' was specified. 491 */ 492 for (i = 0; i < rs->md.raid_disks; i++) { 493 set_bit(In_sync, &rs->dev[i].rdev.flags); 494 rs->dev[i].rdev.recovery_offset = MaxSector; 495 } 496 497 /* 498 * Second, parse the unordered optional arguments 499 */ 500 for (i = 0; i < num_raid_params; i++) { 501 if (!strcasecmp(argv[i], "nosync")) { 502 rs->md.recovery_cp = MaxSector; 503 rs->print_flags |= DMPF_NOSYNC; 504 continue; 505 } 506 if (!strcasecmp(argv[i], "sync")) { 507 rs->md.recovery_cp = 0; 508 rs->print_flags |= DMPF_SYNC; 509 continue; 510 } 511 512 /* The rest of the optional arguments come in key/value pairs */ 513 if ((i + 1) >= num_raid_params) { 514 rs->ti->error = "Wrong number of raid parameters given"; 515 return -EINVAL; 516 } 517 518 key = argv[i++]; 519 520 /* Parameters that take a string value are checked here. */ 521 if (!strcasecmp(key, "raid10_format")) { 522 if (rs->raid_type->level != 10) { 523 rs->ti->error = "'raid10_format' is an invalid parameter for this RAID type"; 524 return -EINVAL; 525 } 526 if (strcmp("near", argv[i])) { 527 rs->ti->error = "Invalid 'raid10_format' value given"; 528 return -EINVAL; 529 } 530 raid10_format = argv[i]; 531 rs->print_flags |= DMPF_RAID10_FORMAT; 532 continue; 533 } 534 535 if (strict_strtoul(argv[i], 10, &value) < 0) { 536 rs->ti->error = "Bad numerical argument given in raid params"; 537 return -EINVAL; 538 } 539 540 /* Parameters that take a numeric value are checked here */ 541 if (!strcasecmp(key, "rebuild")) { 542 if (value >= rs->md.raid_disks) { 543 rs->ti->error = "Invalid rebuild index given"; 544 return -EINVAL; 545 } 546 clear_bit(In_sync, &rs->dev[value].rdev.flags); 547 rs->dev[value].rdev.recovery_offset = 0; 548 rs->print_flags |= DMPF_REBUILD; 549 } else if (!strcasecmp(key, "write_mostly")) { 550 if (rs->raid_type->level != 1) { 551 rs->ti->error = "write_mostly option is only valid for RAID1"; 552 return -EINVAL; 553 } 554 if (value >= rs->md.raid_disks) { 555 rs->ti->error = "Invalid write_mostly drive index given"; 556 return -EINVAL; 557 } 558 set_bit(WriteMostly, &rs->dev[value].rdev.flags); 559 } else if (!strcasecmp(key, "max_write_behind")) { 560 if (rs->raid_type->level != 1) { 561 rs->ti->error = "max_write_behind option is only valid for RAID1"; 562 return -EINVAL; 563 } 564 rs->print_flags |= DMPF_MAX_WRITE_BEHIND; 565 566 /* 567 * In device-mapper, we specify things in sectors, but 568 * MD records this value in kB 569 */ 570 value /= 2; 571 if (value > COUNTER_MAX) { 572 rs->ti->error = "Max write-behind limit out of range"; 573 return -EINVAL; 574 } 575 rs->md.bitmap_info.max_write_behind = value; 576 } else if (!strcasecmp(key, "daemon_sleep")) { 577 rs->print_flags |= DMPF_DAEMON_SLEEP; 578 if (!value || (value > MAX_SCHEDULE_TIMEOUT)) { 579 rs->ti->error = "daemon sleep period out of range"; 580 return -EINVAL; 581 } 582 rs->md.bitmap_info.daemon_sleep = value; 583 } else if (!strcasecmp(key, "stripe_cache")) { 584 rs->print_flags |= DMPF_STRIPE_CACHE; 585 586 /* 587 * In device-mapper, we specify things in sectors, but 588 * MD records this value in kB 589 */ 590 value /= 2; 591 592 if ((rs->raid_type->level != 5) && 593 (rs->raid_type->level != 6)) { 594 rs->ti->error = "Inappropriate argument: stripe_cache"; 595 return -EINVAL; 596 } 597 if (raid5_set_cache_size(&rs->md, (int)value)) { 598 rs->ti->error = "Bad stripe_cache size"; 599 return -EINVAL; 600 } 601 } else if (!strcasecmp(key, "min_recovery_rate")) { 602 rs->print_flags |= DMPF_MIN_RECOVERY_RATE; 603 if (value > INT_MAX) { 604 rs->ti->error = "min_recovery_rate out of range"; 605 return -EINVAL; 606 } 607 rs->md.sync_speed_min = (int)value; 608 } else if (!strcasecmp(key, "max_recovery_rate")) { 609 rs->print_flags |= DMPF_MAX_RECOVERY_RATE; 610 if (value > INT_MAX) { 611 rs->ti->error = "max_recovery_rate out of range"; 612 return -EINVAL; 613 } 614 rs->md.sync_speed_max = (int)value; 615 } else if (!strcasecmp(key, "region_size")) { 616 rs->print_flags |= DMPF_REGION_SIZE; 617 region_size = value; 618 } else if (!strcasecmp(key, "raid10_copies") && 619 (rs->raid_type->level == 10)) { 620 if ((value < 2) || (value > 0xFF)) { 621 rs->ti->error = "Bad value for 'raid10_copies'"; 622 return -EINVAL; 623 } 624 rs->print_flags |= DMPF_RAID10_COPIES; 625 raid10_copies = value; 626 } else { 627 DMERR("Unable to parse RAID parameter: %s", key); 628 rs->ti->error = "Unable to parse RAID parameters"; 629 return -EINVAL; 630 } 631 } 632 633 if (validate_region_size(rs, region_size)) 634 return -EINVAL; 635 636 if (rs->md.chunk_sectors) 637 max_io_len = rs->md.chunk_sectors; 638 else 639 max_io_len = region_size; 640 641 if (dm_set_target_max_io_len(rs->ti, max_io_len)) 642 return -EINVAL; 643 644 if (rs->raid_type->level == 10) { 645 if (raid10_copies > rs->md.raid_disks) { 646 rs->ti->error = "Not enough devices to satisfy specification"; 647 return -EINVAL; 648 } 649 650 /* (Len * #mirrors) / #devices */ 651 sectors_per_dev = rs->ti->len * raid10_copies; 652 sector_div(sectors_per_dev, rs->md.raid_disks); 653 654 rs->md.layout = raid10_format_to_md_layout(raid10_format, 655 raid10_copies); 656 rs->md.new_layout = rs->md.layout; 657 } else if ((rs->raid_type->level > 1) && 658 sector_div(sectors_per_dev, 659 (rs->md.raid_disks - rs->raid_type->parity_devs))) { 660 rs->ti->error = "Target length not divisible by number of data devices"; 661 return -EINVAL; 662 } 663 rs->md.dev_sectors = sectors_per_dev; 664 665 if (validate_rebuild_devices(rs)) 666 return -EINVAL; 667 668 /* Assume there are no metadata devices until the drives are parsed */ 669 rs->md.persistent = 0; 670 rs->md.external = 1; 671 672 return 0; 673 } 674 675 static void do_table_event(struct work_struct *ws) 676 { 677 struct raid_set *rs = container_of(ws, struct raid_set, md.event_work); 678 679 dm_table_event(rs->ti->table); 680 } 681 682 static int raid_is_congested(struct dm_target_callbacks *cb, int bits) 683 { 684 struct raid_set *rs = container_of(cb, struct raid_set, callbacks); 685 686 if (rs->raid_type->level == 1) 687 return md_raid1_congested(&rs->md, bits); 688 689 if (rs->raid_type->level == 10) 690 return md_raid10_congested(&rs->md, bits); 691 692 return md_raid5_congested(&rs->md, bits); 693 } 694 695 /* 696 * This structure is never routinely used by userspace, unlike md superblocks. 697 * Devices with this superblock should only ever be accessed via device-mapper. 698 */ 699 #define DM_RAID_MAGIC 0x64526D44 700 struct dm_raid_superblock { 701 __le32 magic; /* "DmRd" */ 702 __le32 features; /* Used to indicate possible future changes */ 703 704 __le32 num_devices; /* Number of devices in this array. (Max 64) */ 705 __le32 array_position; /* The position of this drive in the array */ 706 707 __le64 events; /* Incremented by md when superblock updated */ 708 __le64 failed_devices; /* Bit field of devices to indicate failures */ 709 710 /* 711 * This offset tracks the progress of the repair or replacement of 712 * an individual drive. 713 */ 714 __le64 disk_recovery_offset; 715 716 /* 717 * This offset tracks the progress of the initial array 718 * synchronisation/parity calculation. 719 */ 720 __le64 array_resync_offset; 721 722 /* 723 * RAID characteristics 724 */ 725 __le32 level; 726 __le32 layout; 727 __le32 stripe_sectors; 728 729 __u8 pad[452]; /* Round struct to 512 bytes. */ 730 /* Always set to 0 when writing. */ 731 } __packed; 732 733 static int read_disk_sb(struct md_rdev *rdev, int size) 734 { 735 BUG_ON(!rdev->sb_page); 736 737 if (rdev->sb_loaded) 738 return 0; 739 740 if (!sync_page_io(rdev, 0, size, rdev->sb_page, READ, 1)) { 741 DMERR("Failed to read superblock of device at position %d", 742 rdev->raid_disk); 743 md_error(rdev->mddev, rdev); 744 return -EINVAL; 745 } 746 747 rdev->sb_loaded = 1; 748 749 return 0; 750 } 751 752 static void super_sync(struct mddev *mddev, struct md_rdev *rdev) 753 { 754 int i; 755 uint64_t failed_devices; 756 struct dm_raid_superblock *sb; 757 struct raid_set *rs = container_of(mddev, struct raid_set, md); 758 759 sb = page_address(rdev->sb_page); 760 failed_devices = le64_to_cpu(sb->failed_devices); 761 762 for (i = 0; i < mddev->raid_disks; i++) 763 if (!rs->dev[i].data_dev || 764 test_bit(Faulty, &(rs->dev[i].rdev.flags))) 765 failed_devices |= (1ULL << i); 766 767 memset(sb, 0, sizeof(*sb)); 768 769 sb->magic = cpu_to_le32(DM_RAID_MAGIC); 770 sb->features = cpu_to_le32(0); /* No features yet */ 771 772 sb->num_devices = cpu_to_le32(mddev->raid_disks); 773 sb->array_position = cpu_to_le32(rdev->raid_disk); 774 775 sb->events = cpu_to_le64(mddev->events); 776 sb->failed_devices = cpu_to_le64(failed_devices); 777 778 sb->disk_recovery_offset = cpu_to_le64(rdev->recovery_offset); 779 sb->array_resync_offset = cpu_to_le64(mddev->recovery_cp); 780 781 sb->level = cpu_to_le32(mddev->level); 782 sb->layout = cpu_to_le32(mddev->layout); 783 sb->stripe_sectors = cpu_to_le32(mddev->chunk_sectors); 784 } 785 786 /* 787 * super_load 788 * 789 * This function creates a superblock if one is not found on the device 790 * and will decide which superblock to use if there's a choice. 791 * 792 * Return: 1 if use rdev, 0 if use refdev, -Exxx otherwise 793 */ 794 static int super_load(struct md_rdev *rdev, struct md_rdev *refdev) 795 { 796 int ret; 797 struct dm_raid_superblock *sb; 798 struct dm_raid_superblock *refsb; 799 uint64_t events_sb, events_refsb; 800 801 rdev->sb_start = 0; 802 rdev->sb_size = sizeof(*sb); 803 804 ret = read_disk_sb(rdev, rdev->sb_size); 805 if (ret) 806 return ret; 807 808 sb = page_address(rdev->sb_page); 809 810 /* 811 * Two cases that we want to write new superblocks and rebuild: 812 * 1) New device (no matching magic number) 813 * 2) Device specified for rebuild (!In_sync w/ offset == 0) 814 */ 815 if ((sb->magic != cpu_to_le32(DM_RAID_MAGIC)) || 816 (!test_bit(In_sync, &rdev->flags) && !rdev->recovery_offset)) { 817 super_sync(rdev->mddev, rdev); 818 819 set_bit(FirstUse, &rdev->flags); 820 821 /* Force writing of superblocks to disk */ 822 set_bit(MD_CHANGE_DEVS, &rdev->mddev->flags); 823 824 /* Any superblock is better than none, choose that if given */ 825 return refdev ? 0 : 1; 826 } 827 828 if (!refdev) 829 return 1; 830 831 events_sb = le64_to_cpu(sb->events); 832 833 refsb = page_address(refdev->sb_page); 834 events_refsb = le64_to_cpu(refsb->events); 835 836 return (events_sb > events_refsb) ? 1 : 0; 837 } 838 839 static int super_init_validation(struct mddev *mddev, struct md_rdev *rdev) 840 { 841 int role; 842 struct raid_set *rs = container_of(mddev, struct raid_set, md); 843 uint64_t events_sb; 844 uint64_t failed_devices; 845 struct dm_raid_superblock *sb; 846 uint32_t new_devs = 0; 847 uint32_t rebuilds = 0; 848 struct md_rdev *r; 849 struct dm_raid_superblock *sb2; 850 851 sb = page_address(rdev->sb_page); 852 events_sb = le64_to_cpu(sb->events); 853 failed_devices = le64_to_cpu(sb->failed_devices); 854 855 /* 856 * Initialise to 1 if this is a new superblock. 857 */ 858 mddev->events = events_sb ? : 1; 859 860 /* 861 * Reshaping is not currently allowed 862 */ 863 if ((le32_to_cpu(sb->level) != mddev->level) || 864 (le32_to_cpu(sb->layout) != mddev->layout) || 865 (le32_to_cpu(sb->stripe_sectors) != mddev->chunk_sectors)) { 866 DMERR("Reshaping arrays not yet supported."); 867 return -EINVAL; 868 } 869 870 /* We can only change the number of devices in RAID1 right now */ 871 if ((rs->raid_type->level != 1) && 872 (le32_to_cpu(sb->num_devices) != mddev->raid_disks)) { 873 DMERR("Reshaping arrays not yet supported."); 874 return -EINVAL; 875 } 876 877 if (!(rs->print_flags & (DMPF_SYNC | DMPF_NOSYNC))) 878 mddev->recovery_cp = le64_to_cpu(sb->array_resync_offset); 879 880 /* 881 * During load, we set FirstUse if a new superblock was written. 882 * There are two reasons we might not have a superblock: 883 * 1) The array is brand new - in which case, all of the 884 * devices must have their In_sync bit set. Also, 885 * recovery_cp must be 0, unless forced. 886 * 2) This is a new device being added to an old array 887 * and the new device needs to be rebuilt - in which 888 * case the In_sync bit will /not/ be set and 889 * recovery_cp must be MaxSector. 890 */ 891 rdev_for_each(r, mddev) { 892 if (!test_bit(In_sync, &r->flags)) { 893 DMINFO("Device %d specified for rebuild: " 894 "Clearing superblock", r->raid_disk); 895 rebuilds++; 896 } else if (test_bit(FirstUse, &r->flags)) 897 new_devs++; 898 } 899 900 if (!rebuilds) { 901 if (new_devs == mddev->raid_disks) { 902 DMINFO("Superblocks created for new array"); 903 set_bit(MD_ARRAY_FIRST_USE, &mddev->flags); 904 } else if (new_devs) { 905 DMERR("New device injected " 906 "into existing array without 'rebuild' " 907 "parameter specified"); 908 return -EINVAL; 909 } 910 } else if (new_devs) { 911 DMERR("'rebuild' devices cannot be " 912 "injected into an array with other first-time devices"); 913 return -EINVAL; 914 } else if (mddev->recovery_cp != MaxSector) { 915 DMERR("'rebuild' specified while array is not in-sync"); 916 return -EINVAL; 917 } 918 919 /* 920 * Now we set the Faulty bit for those devices that are 921 * recorded in the superblock as failed. 922 */ 923 rdev_for_each(r, mddev) { 924 if (!r->sb_page) 925 continue; 926 sb2 = page_address(r->sb_page); 927 sb2->failed_devices = 0; 928 929 /* 930 * Check for any device re-ordering. 931 */ 932 if (!test_bit(FirstUse, &r->flags) && (r->raid_disk >= 0)) { 933 role = le32_to_cpu(sb2->array_position); 934 if (role != r->raid_disk) { 935 if (rs->raid_type->level != 1) { 936 rs->ti->error = "Cannot change device " 937 "positions in RAID array"; 938 return -EINVAL; 939 } 940 DMINFO("RAID1 device #%d now at position #%d", 941 role, r->raid_disk); 942 } 943 944 /* 945 * Partial recovery is performed on 946 * returning failed devices. 947 */ 948 if (failed_devices & (1 << role)) 949 set_bit(Faulty, &r->flags); 950 } 951 } 952 953 return 0; 954 } 955 956 static int super_validate(struct mddev *mddev, struct md_rdev *rdev) 957 { 958 struct dm_raid_superblock *sb = page_address(rdev->sb_page); 959 960 /* 961 * If mddev->events is not set, we know we have not yet initialized 962 * the array. 963 */ 964 if (!mddev->events && super_init_validation(mddev, rdev)) 965 return -EINVAL; 966 967 mddev->bitmap_info.offset = 4096 >> 9; /* Enable bitmap creation */ 968 rdev->mddev->bitmap_info.default_offset = 4096 >> 9; 969 if (!test_bit(FirstUse, &rdev->flags)) { 970 rdev->recovery_offset = le64_to_cpu(sb->disk_recovery_offset); 971 if (rdev->recovery_offset != MaxSector) 972 clear_bit(In_sync, &rdev->flags); 973 } 974 975 /* 976 * If a device comes back, set it as not In_sync and no longer faulty. 977 */ 978 if (test_bit(Faulty, &rdev->flags)) { 979 clear_bit(Faulty, &rdev->flags); 980 clear_bit(In_sync, &rdev->flags); 981 rdev->saved_raid_disk = rdev->raid_disk; 982 rdev->recovery_offset = 0; 983 } 984 985 clear_bit(FirstUse, &rdev->flags); 986 987 return 0; 988 } 989 990 /* 991 * Analyse superblocks and select the freshest. 992 */ 993 static int analyse_superblocks(struct dm_target *ti, struct raid_set *rs) 994 { 995 int ret; 996 unsigned redundancy = 0; 997 struct raid_dev *dev; 998 struct md_rdev *rdev, *tmp, *freshest; 999 struct mddev *mddev = &rs->md; 1000 1001 switch (rs->raid_type->level) { 1002 case 1: 1003 redundancy = rs->md.raid_disks - 1; 1004 break; 1005 case 4: 1006 case 5: 1007 case 6: 1008 redundancy = rs->raid_type->parity_devs; 1009 break; 1010 case 10: 1011 redundancy = raid10_md_layout_to_copies(mddev->layout) - 1; 1012 break; 1013 default: 1014 ti->error = "Unknown RAID type"; 1015 return -EINVAL; 1016 } 1017 1018 freshest = NULL; 1019 rdev_for_each_safe(rdev, tmp, mddev) { 1020 /* 1021 * Skipping super_load due to DMPF_SYNC will cause 1022 * the array to undergo initialization again as 1023 * though it were new. This is the intended effect 1024 * of the "sync" directive. 1025 * 1026 * When reshaping capability is added, we must ensure 1027 * that the "sync" directive is disallowed during the 1028 * reshape. 1029 */ 1030 if (rs->print_flags & DMPF_SYNC) 1031 continue; 1032 1033 if (!rdev->meta_bdev) 1034 continue; 1035 1036 ret = super_load(rdev, freshest); 1037 1038 switch (ret) { 1039 case 1: 1040 freshest = rdev; 1041 break; 1042 case 0: 1043 break; 1044 default: 1045 dev = container_of(rdev, struct raid_dev, rdev); 1046 if (redundancy--) { 1047 if (dev->meta_dev) 1048 dm_put_device(ti, dev->meta_dev); 1049 1050 dev->meta_dev = NULL; 1051 rdev->meta_bdev = NULL; 1052 1053 if (rdev->sb_page) 1054 put_page(rdev->sb_page); 1055 1056 rdev->sb_page = NULL; 1057 1058 rdev->sb_loaded = 0; 1059 1060 /* 1061 * We might be able to salvage the data device 1062 * even though the meta device has failed. For 1063 * now, we behave as though '- -' had been 1064 * set for this device in the table. 1065 */ 1066 if (dev->data_dev) 1067 dm_put_device(ti, dev->data_dev); 1068 1069 dev->data_dev = NULL; 1070 rdev->bdev = NULL; 1071 1072 list_del(&rdev->same_set); 1073 1074 continue; 1075 } 1076 ti->error = "Failed to load superblock"; 1077 return ret; 1078 } 1079 } 1080 1081 if (!freshest) 1082 return 0; 1083 1084 /* 1085 * Validation of the freshest device provides the source of 1086 * validation for the remaining devices. 1087 */ 1088 ti->error = "Unable to assemble array: Invalid superblocks"; 1089 if (super_validate(mddev, freshest)) 1090 return -EINVAL; 1091 1092 rdev_for_each(rdev, mddev) 1093 if ((rdev != freshest) && super_validate(mddev, rdev)) 1094 return -EINVAL; 1095 1096 return 0; 1097 } 1098 1099 /* 1100 * Construct a RAID4/5/6 mapping: 1101 * Args: 1102 * <raid_type> <#raid_params> <raid_params> \ 1103 * <#raid_devs> { <meta_dev1> <dev1> .. <meta_devN> <devN> } 1104 * 1105 * <raid_params> varies by <raid_type>. See 'parse_raid_params' for 1106 * details on possible <raid_params>. 1107 */ 1108 static int raid_ctr(struct dm_target *ti, unsigned argc, char **argv) 1109 { 1110 int ret; 1111 struct raid_type *rt; 1112 unsigned long num_raid_params, num_raid_devs; 1113 struct raid_set *rs = NULL; 1114 1115 /* Must have at least <raid_type> <#raid_params> */ 1116 if (argc < 2) { 1117 ti->error = "Too few arguments"; 1118 return -EINVAL; 1119 } 1120 1121 /* raid type */ 1122 rt = get_raid_type(argv[0]); 1123 if (!rt) { 1124 ti->error = "Unrecognised raid_type"; 1125 return -EINVAL; 1126 } 1127 argc--; 1128 argv++; 1129 1130 /* number of RAID parameters */ 1131 if (strict_strtoul(argv[0], 10, &num_raid_params) < 0) { 1132 ti->error = "Cannot understand number of RAID parameters"; 1133 return -EINVAL; 1134 } 1135 argc--; 1136 argv++; 1137 1138 /* Skip over RAID params for now and find out # of devices */ 1139 if (num_raid_params + 1 > argc) { 1140 ti->error = "Arguments do not agree with counts given"; 1141 return -EINVAL; 1142 } 1143 1144 if ((strict_strtoul(argv[num_raid_params], 10, &num_raid_devs) < 0) || 1145 (num_raid_devs >= INT_MAX)) { 1146 ti->error = "Cannot understand number of raid devices"; 1147 return -EINVAL; 1148 } 1149 1150 rs = context_alloc(ti, rt, (unsigned)num_raid_devs); 1151 if (IS_ERR(rs)) 1152 return PTR_ERR(rs); 1153 1154 ret = parse_raid_params(rs, argv, (unsigned)num_raid_params); 1155 if (ret) 1156 goto bad; 1157 1158 ret = -EINVAL; 1159 1160 argc -= num_raid_params + 1; /* +1: we already have num_raid_devs */ 1161 argv += num_raid_params + 1; 1162 1163 if (argc != (num_raid_devs * 2)) { 1164 ti->error = "Supplied RAID devices does not match the count given"; 1165 goto bad; 1166 } 1167 1168 ret = dev_parms(rs, argv); 1169 if (ret) 1170 goto bad; 1171 1172 rs->md.sync_super = super_sync; 1173 ret = analyse_superblocks(ti, rs); 1174 if (ret) 1175 goto bad; 1176 1177 INIT_WORK(&rs->md.event_work, do_table_event); 1178 ti->private = rs; 1179 ti->num_flush_requests = 1; 1180 1181 mutex_lock(&rs->md.reconfig_mutex); 1182 ret = md_run(&rs->md); 1183 rs->md.in_sync = 0; /* Assume already marked dirty */ 1184 mutex_unlock(&rs->md.reconfig_mutex); 1185 1186 if (ret) { 1187 ti->error = "Fail to run raid array"; 1188 goto bad; 1189 } 1190 1191 if (ti->len != rs->md.array_sectors) { 1192 ti->error = "Array size does not match requested target length"; 1193 ret = -EINVAL; 1194 goto size_mismatch; 1195 } 1196 rs->callbacks.congested_fn = raid_is_congested; 1197 dm_table_add_target_callbacks(ti->table, &rs->callbacks); 1198 1199 mddev_suspend(&rs->md); 1200 return 0; 1201 1202 size_mismatch: 1203 md_stop(&rs->md); 1204 bad: 1205 context_free(rs); 1206 1207 return ret; 1208 } 1209 1210 static void raid_dtr(struct dm_target *ti) 1211 { 1212 struct raid_set *rs = ti->private; 1213 1214 list_del_init(&rs->callbacks.list); 1215 md_stop(&rs->md); 1216 context_free(rs); 1217 } 1218 1219 static int raid_map(struct dm_target *ti, struct bio *bio, union map_info *map_context) 1220 { 1221 struct raid_set *rs = ti->private; 1222 struct mddev *mddev = &rs->md; 1223 1224 mddev->pers->make_request(mddev, bio); 1225 1226 return DM_MAPIO_SUBMITTED; 1227 } 1228 1229 static int raid_status(struct dm_target *ti, status_type_t type, 1230 unsigned status_flags, char *result, unsigned maxlen) 1231 { 1232 struct raid_set *rs = ti->private; 1233 unsigned raid_param_cnt = 1; /* at least 1 for chunksize */ 1234 unsigned sz = 0; 1235 int i, array_in_sync = 0; 1236 sector_t sync; 1237 1238 switch (type) { 1239 case STATUSTYPE_INFO: 1240 DMEMIT("%s %d ", rs->raid_type->name, rs->md.raid_disks); 1241 1242 if (test_bit(MD_RECOVERY_RUNNING, &rs->md.recovery)) 1243 sync = rs->md.curr_resync_completed; 1244 else 1245 sync = rs->md.recovery_cp; 1246 1247 if (sync >= rs->md.resync_max_sectors) { 1248 array_in_sync = 1; 1249 sync = rs->md.resync_max_sectors; 1250 } else { 1251 /* 1252 * The array may be doing an initial sync, or it may 1253 * be rebuilding individual components. If all the 1254 * devices are In_sync, then it is the array that is 1255 * being initialized. 1256 */ 1257 for (i = 0; i < rs->md.raid_disks; i++) 1258 if (!test_bit(In_sync, &rs->dev[i].rdev.flags)) 1259 array_in_sync = 1; 1260 } 1261 /* 1262 * Status characters: 1263 * 'D' = Dead/Failed device 1264 * 'a' = Alive but not in-sync 1265 * 'A' = Alive and in-sync 1266 */ 1267 for (i = 0; i < rs->md.raid_disks; i++) { 1268 if (test_bit(Faulty, &rs->dev[i].rdev.flags)) 1269 DMEMIT("D"); 1270 else if (!array_in_sync || 1271 !test_bit(In_sync, &rs->dev[i].rdev.flags)) 1272 DMEMIT("a"); 1273 else 1274 DMEMIT("A"); 1275 } 1276 1277 /* 1278 * In-sync ratio: 1279 * The in-sync ratio shows the progress of: 1280 * - Initializing the array 1281 * - Rebuilding a subset of devices of the array 1282 * The user can distinguish between the two by referring 1283 * to the status characters. 1284 */ 1285 DMEMIT(" %llu/%llu", 1286 (unsigned long long) sync, 1287 (unsigned long long) rs->md.resync_max_sectors); 1288 1289 break; 1290 case STATUSTYPE_TABLE: 1291 /* The string you would use to construct this array */ 1292 for (i = 0; i < rs->md.raid_disks; i++) { 1293 if ((rs->print_flags & DMPF_REBUILD) && 1294 rs->dev[i].data_dev && 1295 !test_bit(In_sync, &rs->dev[i].rdev.flags)) 1296 raid_param_cnt += 2; /* for rebuilds */ 1297 if (rs->dev[i].data_dev && 1298 test_bit(WriteMostly, &rs->dev[i].rdev.flags)) 1299 raid_param_cnt += 2; 1300 } 1301 1302 raid_param_cnt += (hweight32(rs->print_flags & ~DMPF_REBUILD) * 2); 1303 if (rs->print_flags & (DMPF_SYNC | DMPF_NOSYNC)) 1304 raid_param_cnt--; 1305 1306 DMEMIT("%s %u %u", rs->raid_type->name, 1307 raid_param_cnt, rs->md.chunk_sectors); 1308 1309 if ((rs->print_flags & DMPF_SYNC) && 1310 (rs->md.recovery_cp == MaxSector)) 1311 DMEMIT(" sync"); 1312 if (rs->print_flags & DMPF_NOSYNC) 1313 DMEMIT(" nosync"); 1314 1315 for (i = 0; i < rs->md.raid_disks; i++) 1316 if ((rs->print_flags & DMPF_REBUILD) && 1317 rs->dev[i].data_dev && 1318 !test_bit(In_sync, &rs->dev[i].rdev.flags)) 1319 DMEMIT(" rebuild %u", i); 1320 1321 if (rs->print_flags & DMPF_DAEMON_SLEEP) 1322 DMEMIT(" daemon_sleep %lu", 1323 rs->md.bitmap_info.daemon_sleep); 1324 1325 if (rs->print_flags & DMPF_MIN_RECOVERY_RATE) 1326 DMEMIT(" min_recovery_rate %d", rs->md.sync_speed_min); 1327 1328 if (rs->print_flags & DMPF_MAX_RECOVERY_RATE) 1329 DMEMIT(" max_recovery_rate %d", rs->md.sync_speed_max); 1330 1331 for (i = 0; i < rs->md.raid_disks; i++) 1332 if (rs->dev[i].data_dev && 1333 test_bit(WriteMostly, &rs->dev[i].rdev.flags)) 1334 DMEMIT(" write_mostly %u", i); 1335 1336 if (rs->print_flags & DMPF_MAX_WRITE_BEHIND) 1337 DMEMIT(" max_write_behind %lu", 1338 rs->md.bitmap_info.max_write_behind); 1339 1340 if (rs->print_flags & DMPF_STRIPE_CACHE) { 1341 struct r5conf *conf = rs->md.private; 1342 1343 /* convert from kiB to sectors */ 1344 DMEMIT(" stripe_cache %d", 1345 conf ? conf->max_nr_stripes * 2 : 0); 1346 } 1347 1348 if (rs->print_flags & DMPF_REGION_SIZE) 1349 DMEMIT(" region_size %lu", 1350 rs->md.bitmap_info.chunksize >> 9); 1351 1352 if (rs->print_flags & DMPF_RAID10_COPIES) 1353 DMEMIT(" raid10_copies %u", 1354 raid10_md_layout_to_copies(rs->md.layout)); 1355 1356 if (rs->print_flags & DMPF_RAID10_FORMAT) 1357 DMEMIT(" raid10_format near"); 1358 1359 DMEMIT(" %d", rs->md.raid_disks); 1360 for (i = 0; i < rs->md.raid_disks; i++) { 1361 if (rs->dev[i].meta_dev) 1362 DMEMIT(" %s", rs->dev[i].meta_dev->name); 1363 else 1364 DMEMIT(" -"); 1365 1366 if (rs->dev[i].data_dev) 1367 DMEMIT(" %s", rs->dev[i].data_dev->name); 1368 else 1369 DMEMIT(" -"); 1370 } 1371 } 1372 1373 return 0; 1374 } 1375 1376 static int raid_iterate_devices(struct dm_target *ti, iterate_devices_callout_fn fn, void *data) 1377 { 1378 struct raid_set *rs = ti->private; 1379 unsigned i; 1380 int ret = 0; 1381 1382 for (i = 0; !ret && i < rs->md.raid_disks; i++) 1383 if (rs->dev[i].data_dev) 1384 ret = fn(ti, 1385 rs->dev[i].data_dev, 1386 0, /* No offset on data devs */ 1387 rs->md.dev_sectors, 1388 data); 1389 1390 return ret; 1391 } 1392 1393 static void raid_io_hints(struct dm_target *ti, struct queue_limits *limits) 1394 { 1395 struct raid_set *rs = ti->private; 1396 unsigned chunk_size = rs->md.chunk_sectors << 9; 1397 struct r5conf *conf = rs->md.private; 1398 1399 blk_limits_io_min(limits, chunk_size); 1400 blk_limits_io_opt(limits, chunk_size * (conf->raid_disks - conf->max_degraded)); 1401 } 1402 1403 static void raid_presuspend(struct dm_target *ti) 1404 { 1405 struct raid_set *rs = ti->private; 1406 1407 md_stop_writes(&rs->md); 1408 } 1409 1410 static void raid_postsuspend(struct dm_target *ti) 1411 { 1412 struct raid_set *rs = ti->private; 1413 1414 mddev_suspend(&rs->md); 1415 } 1416 1417 static void raid_resume(struct dm_target *ti) 1418 { 1419 struct raid_set *rs = ti->private; 1420 1421 set_bit(MD_CHANGE_DEVS, &rs->md.flags); 1422 if (!rs->bitmap_loaded) { 1423 bitmap_load(&rs->md); 1424 rs->bitmap_loaded = 1; 1425 } 1426 1427 clear_bit(MD_RECOVERY_FROZEN, &rs->md.recovery); 1428 mddev_resume(&rs->md); 1429 } 1430 1431 static struct target_type raid_target = { 1432 .name = "raid", 1433 .version = {1, 3, 1}, 1434 .module = THIS_MODULE, 1435 .ctr = raid_ctr, 1436 .dtr = raid_dtr, 1437 .map = raid_map, 1438 .status = raid_status, 1439 .iterate_devices = raid_iterate_devices, 1440 .io_hints = raid_io_hints, 1441 .presuspend = raid_presuspend, 1442 .postsuspend = raid_postsuspend, 1443 .resume = raid_resume, 1444 }; 1445 1446 static int __init dm_raid_init(void) 1447 { 1448 return dm_register_target(&raid_target); 1449 } 1450 1451 static void __exit dm_raid_exit(void) 1452 { 1453 dm_unregister_target(&raid_target); 1454 } 1455 1456 module_init(dm_raid_init); 1457 module_exit(dm_raid_exit); 1458 1459 MODULE_DESCRIPTION(DM_NAME " raid4/5/6 target"); 1460 MODULE_ALIAS("dm-raid1"); 1461 MODULE_ALIAS("dm-raid10"); 1462 MODULE_ALIAS("dm-raid4"); 1463 MODULE_ALIAS("dm-raid5"); 1464 MODULE_ALIAS("dm-raid6"); 1465 MODULE_AUTHOR("Neil Brown <dm-devel@redhat.com>"); 1466 MODULE_LICENSE("GPL"); 1467