1 /* 2 * Copyright (C) 2010-2011 Neil Brown 3 * Copyright (C) 2010-2016 Red Hat, Inc. All rights reserved. 4 * 5 * This file is released under the GPL. 6 */ 7 8 #include <linux/slab.h> 9 #include <linux/module.h> 10 11 #include "md.h" 12 #include "raid1.h" 13 #include "raid5.h" 14 #include "raid10.h" 15 #include "bitmap.h" 16 17 #include <linux/device-mapper.h> 18 19 #define DM_MSG_PREFIX "raid" 20 #define MAX_RAID_DEVICES 253 /* md-raid kernel limit */ 21 22 /* 23 * Minimum sectors of free reshape space per raid device 24 */ 25 #define MIN_FREE_RESHAPE_SPACE to_sector(4*4096) 26 27 static bool devices_handle_discard_safely = false; 28 29 /* 30 * The following flags are used by dm-raid.c to set up the array state. 31 * They must be cleared before md_run is called. 32 */ 33 #define FirstUse 10 /* rdev flag */ 34 35 struct raid_dev { 36 /* 37 * Two DM devices, one to hold metadata and one to hold the 38 * actual data/parity. The reason for this is to not confuse 39 * ti->len and give more flexibility in altering size and 40 * characteristics. 41 * 42 * While it is possible for this device to be associated 43 * with a different physical device than the data_dev, it 44 * is intended for it to be the same. 45 * |--------- Physical Device ---------| 46 * |- meta_dev -|------ data_dev ------| 47 */ 48 struct dm_dev *meta_dev; 49 struct dm_dev *data_dev; 50 struct md_rdev rdev; 51 }; 52 53 /* 54 * Bits for establishing rs->ctr_flags 55 * 56 * 1 = no flag value 57 * 2 = flag with value 58 */ 59 #define __CTR_FLAG_SYNC 0 /* 1 */ /* Not with raid0! */ 60 #define __CTR_FLAG_NOSYNC 1 /* 1 */ /* Not with raid0! */ 61 #define __CTR_FLAG_REBUILD 2 /* 2 */ /* Not with raid0! */ 62 #define __CTR_FLAG_DAEMON_SLEEP 3 /* 2 */ /* Not with raid0! */ 63 #define __CTR_FLAG_MIN_RECOVERY_RATE 4 /* 2 */ /* Not with raid0! */ 64 #define __CTR_FLAG_MAX_RECOVERY_RATE 5 /* 2 */ /* Not with raid0! */ 65 #define __CTR_FLAG_MAX_WRITE_BEHIND 6 /* 2 */ /* Only with raid1! */ 66 #define __CTR_FLAG_WRITE_MOSTLY 7 /* 2 */ /* Only with raid1! */ 67 #define __CTR_FLAG_STRIPE_CACHE 8 /* 2 */ /* Only with raid4/5/6! */ 68 #define __CTR_FLAG_REGION_SIZE 9 /* 2 */ /* Not with raid0! */ 69 #define __CTR_FLAG_RAID10_COPIES 10 /* 2 */ /* Only with raid10 */ 70 #define __CTR_FLAG_RAID10_FORMAT 11 /* 2 */ /* Only with raid10 */ 71 /* New for v1.9.0 */ 72 #define __CTR_FLAG_DELTA_DISKS 12 /* 2 */ /* Only with reshapable raid1/4/5/6/10! */ 73 #define __CTR_FLAG_DATA_OFFSET 13 /* 2 */ /* Only with reshapable raid4/5/6/10! */ 74 #define __CTR_FLAG_RAID10_USE_NEAR_SETS 14 /* 2 */ /* Only with raid10! */ 75 76 /* 77 * Flags for rs->ctr_flags field. 78 */ 79 #define CTR_FLAG_SYNC (1 << __CTR_FLAG_SYNC) 80 #define CTR_FLAG_NOSYNC (1 << __CTR_FLAG_NOSYNC) 81 #define CTR_FLAG_REBUILD (1 << __CTR_FLAG_REBUILD) 82 #define CTR_FLAG_DAEMON_SLEEP (1 << __CTR_FLAG_DAEMON_SLEEP) 83 #define CTR_FLAG_MIN_RECOVERY_RATE (1 << __CTR_FLAG_MIN_RECOVERY_RATE) 84 #define CTR_FLAG_MAX_RECOVERY_RATE (1 << __CTR_FLAG_MAX_RECOVERY_RATE) 85 #define CTR_FLAG_MAX_WRITE_BEHIND (1 << __CTR_FLAG_MAX_WRITE_BEHIND) 86 #define CTR_FLAG_WRITE_MOSTLY (1 << __CTR_FLAG_WRITE_MOSTLY) 87 #define CTR_FLAG_STRIPE_CACHE (1 << __CTR_FLAG_STRIPE_CACHE) 88 #define CTR_FLAG_REGION_SIZE (1 << __CTR_FLAG_REGION_SIZE) 89 #define CTR_FLAG_RAID10_COPIES (1 << __CTR_FLAG_RAID10_COPIES) 90 #define CTR_FLAG_RAID10_FORMAT (1 << __CTR_FLAG_RAID10_FORMAT) 91 #define CTR_FLAG_DELTA_DISKS (1 << __CTR_FLAG_DELTA_DISKS) 92 #define CTR_FLAG_DATA_OFFSET (1 << __CTR_FLAG_DATA_OFFSET) 93 #define CTR_FLAG_RAID10_USE_NEAR_SETS (1 << __CTR_FLAG_RAID10_USE_NEAR_SETS) 94 95 /* 96 * Definitions of various constructor flags to 97 * be used in checks of valid / invalid flags 98 * per raid level. 99 */ 100 /* Define all any sync flags */ 101 #define CTR_FLAGS_ANY_SYNC (CTR_FLAG_SYNC | CTR_FLAG_NOSYNC) 102 103 /* Define flags for options without argument (e.g. 'nosync') */ 104 #define CTR_FLAG_OPTIONS_NO_ARGS (CTR_FLAGS_ANY_SYNC | \ 105 CTR_FLAG_RAID10_USE_NEAR_SETS) 106 107 /* Define flags for options with one argument (e.g. 'delta_disks +2') */ 108 #define CTR_FLAG_OPTIONS_ONE_ARG (CTR_FLAG_REBUILD | \ 109 CTR_FLAG_WRITE_MOSTLY | \ 110 CTR_FLAG_DAEMON_SLEEP | \ 111 CTR_FLAG_MIN_RECOVERY_RATE | \ 112 CTR_FLAG_MAX_RECOVERY_RATE | \ 113 CTR_FLAG_MAX_WRITE_BEHIND | \ 114 CTR_FLAG_STRIPE_CACHE | \ 115 CTR_FLAG_REGION_SIZE | \ 116 CTR_FLAG_RAID10_COPIES | \ 117 CTR_FLAG_RAID10_FORMAT | \ 118 CTR_FLAG_DELTA_DISKS | \ 119 CTR_FLAG_DATA_OFFSET) 120 121 /* Valid options definitions per raid level... */ 122 123 /* "raid0" does only accept data offset */ 124 #define RAID0_VALID_FLAGS (CTR_FLAG_DATA_OFFSET) 125 126 /* "raid1" does not accept stripe cache, data offset, delta_disks or any raid10 options */ 127 #define RAID1_VALID_FLAGS (CTR_FLAGS_ANY_SYNC | \ 128 CTR_FLAG_REBUILD | \ 129 CTR_FLAG_WRITE_MOSTLY | \ 130 CTR_FLAG_DAEMON_SLEEP | \ 131 CTR_FLAG_MIN_RECOVERY_RATE | \ 132 CTR_FLAG_MAX_RECOVERY_RATE | \ 133 CTR_FLAG_MAX_WRITE_BEHIND | \ 134 CTR_FLAG_REGION_SIZE | \ 135 CTR_FLAG_DELTA_DISKS | \ 136 CTR_FLAG_DATA_OFFSET) 137 138 /* "raid10" does not accept any raid1 or stripe cache options */ 139 #define RAID10_VALID_FLAGS (CTR_FLAGS_ANY_SYNC | \ 140 CTR_FLAG_REBUILD | \ 141 CTR_FLAG_DAEMON_SLEEP | \ 142 CTR_FLAG_MIN_RECOVERY_RATE | \ 143 CTR_FLAG_MAX_RECOVERY_RATE | \ 144 CTR_FLAG_REGION_SIZE | \ 145 CTR_FLAG_RAID10_COPIES | \ 146 CTR_FLAG_RAID10_FORMAT | \ 147 CTR_FLAG_DELTA_DISKS | \ 148 CTR_FLAG_DATA_OFFSET | \ 149 CTR_FLAG_RAID10_USE_NEAR_SETS) 150 151 /* 152 * "raid4/5/6" do not accept any raid1 or raid10 specific options 153 * 154 * "raid6" does not accept "nosync", because it is not guaranteed 155 * that both parity and q-syndrome are being written properly with 156 * any writes 157 */ 158 #define RAID45_VALID_FLAGS (CTR_FLAGS_ANY_SYNC | \ 159 CTR_FLAG_REBUILD | \ 160 CTR_FLAG_DAEMON_SLEEP | \ 161 CTR_FLAG_MIN_RECOVERY_RATE | \ 162 CTR_FLAG_MAX_RECOVERY_RATE | \ 163 CTR_FLAG_MAX_WRITE_BEHIND | \ 164 CTR_FLAG_STRIPE_CACHE | \ 165 CTR_FLAG_REGION_SIZE | \ 166 CTR_FLAG_DELTA_DISKS | \ 167 CTR_FLAG_DATA_OFFSET) 168 169 #define RAID6_VALID_FLAGS (CTR_FLAG_SYNC | \ 170 CTR_FLAG_REBUILD | \ 171 CTR_FLAG_DAEMON_SLEEP | \ 172 CTR_FLAG_MIN_RECOVERY_RATE | \ 173 CTR_FLAG_MAX_RECOVERY_RATE | \ 174 CTR_FLAG_MAX_WRITE_BEHIND | \ 175 CTR_FLAG_STRIPE_CACHE | \ 176 CTR_FLAG_REGION_SIZE | \ 177 CTR_FLAG_DELTA_DISKS | \ 178 CTR_FLAG_DATA_OFFSET) 179 /* ...valid options definitions per raid level */ 180 181 /* 182 * Flags for rs->runtime_flags field 183 * (RT_FLAG prefix meaning "runtime flag") 184 * 185 * These are all internal and used to define runtime state, 186 * e.g. to prevent another resume from preresume processing 187 * the raid set all over again. 188 */ 189 #define RT_FLAG_RS_PRERESUMED 0 190 #define RT_FLAG_RS_RESUMED 1 191 #define RT_FLAG_RS_BITMAP_LOADED 2 192 #define RT_FLAG_UPDATE_SBS 3 193 #define RT_FLAG_RESHAPE_RS 4 194 #define RT_FLAG_KEEP_RS_FROZEN 5 195 196 /* Array elements of 64 bit needed for rebuild/failed disk bits */ 197 #define DISKS_ARRAY_ELEMS ((MAX_RAID_DEVICES + (sizeof(uint64_t) * 8 - 1)) / sizeof(uint64_t) / 8) 198 199 /* 200 * raid set level, layout and chunk sectors backup/restore 201 */ 202 struct rs_layout { 203 int new_level; 204 int new_layout; 205 int new_chunk_sectors; 206 }; 207 208 struct raid_set { 209 struct dm_target *ti; 210 211 uint32_t bitmap_loaded; 212 uint32_t stripe_cache_entries; 213 unsigned long ctr_flags; 214 unsigned long runtime_flags; 215 216 uint64_t rebuild_disks[DISKS_ARRAY_ELEMS]; 217 218 int raid_disks; 219 int delta_disks; 220 int data_offset; 221 int raid10_copies; 222 int requested_bitmap_chunk_sectors; 223 224 struct mddev md; 225 struct raid_type *raid_type; 226 struct dm_target_callbacks callbacks; 227 228 struct raid_dev dev[0]; 229 }; 230 231 static void rs_config_backup(struct raid_set *rs, struct rs_layout *l) 232 { 233 struct mddev *mddev = &rs->md; 234 235 l->new_level = mddev->new_level; 236 l->new_layout = mddev->new_layout; 237 l->new_chunk_sectors = mddev->new_chunk_sectors; 238 } 239 240 static void rs_config_restore(struct raid_set *rs, struct rs_layout *l) 241 { 242 struct mddev *mddev = &rs->md; 243 244 mddev->new_level = l->new_level; 245 mddev->new_layout = l->new_layout; 246 mddev->new_chunk_sectors = l->new_chunk_sectors; 247 } 248 249 /* raid10 algorithms (i.e. formats) */ 250 #define ALGORITHM_RAID10_DEFAULT 0 251 #define ALGORITHM_RAID10_NEAR 1 252 #define ALGORITHM_RAID10_OFFSET 2 253 #define ALGORITHM_RAID10_FAR 3 254 255 /* Supported raid types and properties. */ 256 static struct raid_type { 257 const char *name; /* RAID algorithm. */ 258 const char *descr; /* Descriptor text for logging. */ 259 const unsigned int parity_devs; /* # of parity devices. */ 260 const unsigned int minimal_devs;/* minimal # of devices in set. */ 261 const unsigned int level; /* RAID level. */ 262 const unsigned int algorithm; /* RAID algorithm. */ 263 } raid_types[] = { 264 {"raid0", "raid0 (striping)", 0, 2, 0, 0 /* NONE */}, 265 {"raid1", "raid1 (mirroring)", 0, 2, 1, 0 /* NONE */}, 266 {"raid10_far", "raid10 far (striped mirrors)", 0, 2, 10, ALGORITHM_RAID10_FAR}, 267 {"raid10_offset", "raid10 offset (striped mirrors)", 0, 2, 10, ALGORITHM_RAID10_OFFSET}, 268 {"raid10_near", "raid10 near (striped mirrors)", 0, 2, 10, ALGORITHM_RAID10_NEAR}, 269 {"raid10", "raid10 (striped mirrors)", 0, 2, 10, ALGORITHM_RAID10_DEFAULT}, 270 {"raid4", "raid4 (dedicated last parity disk)", 1, 2, 4, ALGORITHM_PARITY_N}, /* raid4 layout = raid5_n */ 271 {"raid5_n", "raid5 (dedicated last parity disk)", 1, 2, 5, ALGORITHM_PARITY_N}, 272 {"raid5_ls", "raid5 (left symmetric)", 1, 2, 5, ALGORITHM_LEFT_SYMMETRIC}, 273 {"raid5_rs", "raid5 (right symmetric)", 1, 2, 5, ALGORITHM_RIGHT_SYMMETRIC}, 274 {"raid5_la", "raid5 (left asymmetric)", 1, 2, 5, ALGORITHM_LEFT_ASYMMETRIC}, 275 {"raid5_ra", "raid5 (right asymmetric)", 1, 2, 5, ALGORITHM_RIGHT_ASYMMETRIC}, 276 {"raid6_zr", "raid6 (zero restart)", 2, 4, 6, ALGORITHM_ROTATING_ZERO_RESTART}, 277 {"raid6_nr", "raid6 (N restart)", 2, 4, 6, ALGORITHM_ROTATING_N_RESTART}, 278 {"raid6_nc", "raid6 (N continue)", 2, 4, 6, ALGORITHM_ROTATING_N_CONTINUE}, 279 {"raid6_n_6", "raid6 (dedicated parity/Q n/6)", 2, 4, 6, ALGORITHM_PARITY_N_6}, 280 {"raid6_ls_6", "raid6 (left symmetric dedicated Q 6)", 2, 4, 6, ALGORITHM_LEFT_SYMMETRIC_6}, 281 {"raid6_rs_6", "raid6 (right symmetric dedicated Q 6)", 2, 4, 6, ALGORITHM_RIGHT_SYMMETRIC_6}, 282 {"raid6_la_6", "raid6 (left asymmetric dedicated Q 6)", 2, 4, 6, ALGORITHM_LEFT_ASYMMETRIC_6}, 283 {"raid6_ra_6", "raid6 (right asymmetric dedicated Q 6)", 2, 4, 6, ALGORITHM_RIGHT_ASYMMETRIC_6} 284 }; 285 286 /* True, if @v is in inclusive range [@min, @max] */ 287 static bool __within_range(long v, long min, long max) 288 { 289 return v >= min && v <= max; 290 } 291 292 /* All table line arguments are defined here */ 293 static struct arg_name_flag { 294 const unsigned long flag; 295 const char *name; 296 } __arg_name_flags[] = { 297 { CTR_FLAG_SYNC, "sync"}, 298 { CTR_FLAG_NOSYNC, "nosync"}, 299 { CTR_FLAG_REBUILD, "rebuild"}, 300 { CTR_FLAG_DAEMON_SLEEP, "daemon_sleep"}, 301 { CTR_FLAG_MIN_RECOVERY_RATE, "min_recovery_rate"}, 302 { CTR_FLAG_MAX_RECOVERY_RATE, "max_recovery_rate"}, 303 { CTR_FLAG_MAX_WRITE_BEHIND, "max_write_behind"}, 304 { CTR_FLAG_WRITE_MOSTLY, "write_mostly"}, 305 { CTR_FLAG_STRIPE_CACHE, "stripe_cache"}, 306 { CTR_FLAG_REGION_SIZE, "region_size"}, 307 { CTR_FLAG_RAID10_COPIES, "raid10_copies"}, 308 { CTR_FLAG_RAID10_FORMAT, "raid10_format"}, 309 { CTR_FLAG_DATA_OFFSET, "data_offset"}, 310 { CTR_FLAG_DELTA_DISKS, "delta_disks"}, 311 { CTR_FLAG_RAID10_USE_NEAR_SETS, "raid10_use_near_sets"}, 312 }; 313 314 /* Return argument name string for given @flag */ 315 static const char *dm_raid_arg_name_by_flag(const uint32_t flag) 316 { 317 if (hweight32(flag) == 1) { 318 struct arg_name_flag *anf = __arg_name_flags + ARRAY_SIZE(__arg_name_flags); 319 320 while (anf-- > __arg_name_flags) 321 if (flag & anf->flag) 322 return anf->name; 323 324 } else 325 DMERR("%s called with more than one flag!", __func__); 326 327 return NULL; 328 } 329 330 /* 331 * Bool helpers to test for various raid levels of a raid set. 332 * It's level as reported by the superblock rather than 333 * the requested raid_type passed to the constructor. 334 */ 335 /* Return true, if raid set in @rs is raid0 */ 336 static bool rs_is_raid0(struct raid_set *rs) 337 { 338 return !rs->md.level; 339 } 340 341 /* Return true, if raid set in @rs is raid1 */ 342 static bool rs_is_raid1(struct raid_set *rs) 343 { 344 return rs->md.level == 1; 345 } 346 347 /* Return true, if raid set in @rs is raid10 */ 348 static bool rs_is_raid10(struct raid_set *rs) 349 { 350 return rs->md.level == 10; 351 } 352 353 /* Return true, if raid set in @rs is level 6 */ 354 static bool rs_is_raid6(struct raid_set *rs) 355 { 356 return rs->md.level == 6; 357 } 358 359 /* Return true, if raid set in @rs is level 4, 5 or 6 */ 360 static bool rs_is_raid456(struct raid_set *rs) 361 { 362 return __within_range(rs->md.level, 4, 6); 363 } 364 365 /* Return true, if raid set in @rs is reshapable */ 366 static bool __is_raid10_far(int layout); 367 static bool rs_is_reshapable(struct raid_set *rs) 368 { 369 return rs_is_raid456(rs) || 370 (rs_is_raid10(rs) && !__is_raid10_far(rs->md.new_layout)); 371 } 372 373 /* Return true, if raid set in @rs is recovering */ 374 static bool rs_is_recovering(struct raid_set *rs) 375 { 376 return rs->md.recovery_cp < rs->dev[0].rdev.sectors; 377 } 378 379 /* Return true, if raid set in @rs is reshaping */ 380 static bool rs_is_reshaping(struct raid_set *rs) 381 { 382 return rs->md.reshape_position != MaxSector; 383 } 384 385 /* 386 * bool helpers to test for various raid levels of a raid type @rt 387 */ 388 389 /* Return true, if raid type in @rt is raid0 */ 390 static bool rt_is_raid0(struct raid_type *rt) 391 { 392 return !rt->level; 393 } 394 395 /* Return true, if raid type in @rt is raid1 */ 396 static bool rt_is_raid1(struct raid_type *rt) 397 { 398 return rt->level == 1; 399 } 400 401 /* Return true, if raid type in @rt is raid10 */ 402 static bool rt_is_raid10(struct raid_type *rt) 403 { 404 return rt->level == 10; 405 } 406 407 /* Return true, if raid type in @rt is raid4/5 */ 408 static bool rt_is_raid45(struct raid_type *rt) 409 { 410 return __within_range(rt->level, 4, 5); 411 } 412 413 /* Return true, if raid type in @rt is raid6 */ 414 static bool rt_is_raid6(struct raid_type *rt) 415 { 416 return rt->level == 6; 417 } 418 419 /* Return true, if raid type in @rt is raid4/5/6 */ 420 static bool rt_is_raid456(struct raid_type *rt) 421 { 422 return __within_range(rt->level, 4, 6); 423 } 424 /* END: raid level bools */ 425 426 /* Return valid ctr flags for the raid level of @rs */ 427 static unsigned long __valid_flags(struct raid_set *rs) 428 { 429 if (rt_is_raid0(rs->raid_type)) 430 return RAID0_VALID_FLAGS; 431 else if (rt_is_raid1(rs->raid_type)) 432 return RAID1_VALID_FLAGS; 433 else if (rt_is_raid10(rs->raid_type)) 434 return RAID10_VALID_FLAGS; 435 else if (rt_is_raid45(rs->raid_type)) 436 return RAID45_VALID_FLAGS; 437 else if (rt_is_raid6(rs->raid_type)) 438 return RAID6_VALID_FLAGS; 439 440 return 0; 441 } 442 443 /* 444 * Check for valid flags set on @rs 445 * 446 * Has to be called after parsing of the ctr flags! 447 */ 448 static int rs_check_for_valid_flags(struct raid_set *rs) 449 { 450 if (rs->ctr_flags & ~__valid_flags(rs)) { 451 rs->ti->error = "Invalid flags combination"; 452 return -EINVAL; 453 } 454 455 return 0; 456 } 457 458 /* MD raid10 bit definitions and helpers */ 459 #define RAID10_OFFSET (1 << 16) /* stripes with data copies area adjacent on devices */ 460 #define RAID10_BROCKEN_USE_FAR_SETS (1 << 17) /* Broken in raid10.c: use sets instead of whole stripe rotation */ 461 #define RAID10_USE_FAR_SETS (1 << 18) /* Use sets instead of whole stripe rotation */ 462 #define RAID10_FAR_COPIES_SHIFT 8 /* raid10 # far copies shift (2nd byte of layout) */ 463 464 /* Return md raid10 near copies for @layout */ 465 static unsigned int __raid10_near_copies(int layout) 466 { 467 return layout & 0xFF; 468 } 469 470 /* Return md raid10 far copies for @layout */ 471 static unsigned int __raid10_far_copies(int layout) 472 { 473 return __raid10_near_copies(layout >> RAID10_FAR_COPIES_SHIFT); 474 } 475 476 /* Return true if md raid10 offset for @layout */ 477 static bool __is_raid10_offset(int layout) 478 { 479 return !!(layout & RAID10_OFFSET); 480 } 481 482 /* Return true if md raid10 near for @layout */ 483 static bool __is_raid10_near(int layout) 484 { 485 return !__is_raid10_offset(layout) && __raid10_near_copies(layout) > 1; 486 } 487 488 /* Return true if md raid10 far for @layout */ 489 static bool __is_raid10_far(int layout) 490 { 491 return !__is_raid10_offset(layout) && __raid10_far_copies(layout) > 1; 492 } 493 494 /* Return md raid10 layout string for @layout */ 495 static const char *raid10_md_layout_to_format(int layout) 496 { 497 /* 498 * Bit 16 stands for "offset" 499 * (i.e. adjacent stripes hold copies) 500 * 501 * Refer to MD's raid10.c for details 502 */ 503 if (__is_raid10_offset(layout)) 504 return "offset"; 505 506 if (__raid10_near_copies(layout) > 1) 507 return "near"; 508 509 WARN_ON(__raid10_far_copies(layout) < 2); 510 511 return "far"; 512 } 513 514 /* Return md raid10 algorithm for @name */ 515 static int raid10_name_to_format(const char *name) 516 { 517 if (!strcasecmp(name, "near")) 518 return ALGORITHM_RAID10_NEAR; 519 else if (!strcasecmp(name, "offset")) 520 return ALGORITHM_RAID10_OFFSET; 521 else if (!strcasecmp(name, "far")) 522 return ALGORITHM_RAID10_FAR; 523 524 return -EINVAL; 525 } 526 527 /* Return md raid10 copies for @layout */ 528 static unsigned int raid10_md_layout_to_copies(int layout) 529 { 530 return max(__raid10_near_copies(layout), __raid10_far_copies(layout)); 531 } 532 533 /* Return md raid10 format id for @format string */ 534 static int raid10_format_to_md_layout(struct raid_set *rs, 535 unsigned int algorithm, 536 unsigned int copies) 537 { 538 unsigned int n = 1, f = 1, r = 0; 539 540 /* 541 * MD resilienece flaw: 542 * 543 * enabling use_far_sets for far/offset formats causes copies 544 * to be colocated on the same devs together with their origins! 545 * 546 * -> disable it for now in the definition above 547 */ 548 if (algorithm == ALGORITHM_RAID10_DEFAULT || 549 algorithm == ALGORITHM_RAID10_NEAR) 550 n = copies; 551 552 else if (algorithm == ALGORITHM_RAID10_OFFSET) { 553 f = copies; 554 r = RAID10_OFFSET; 555 if (!test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags)) 556 r |= RAID10_USE_FAR_SETS; 557 558 } else if (algorithm == ALGORITHM_RAID10_FAR) { 559 f = copies; 560 r = !RAID10_OFFSET; 561 if (!test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags)) 562 r |= RAID10_USE_FAR_SETS; 563 564 } else 565 return -EINVAL; 566 567 return r | (f << RAID10_FAR_COPIES_SHIFT) | n; 568 } 569 /* END: MD raid10 bit definitions and helpers */ 570 571 /* Check for any of the raid10 algorithms */ 572 static bool __got_raid10(struct raid_type *rtp, const int layout) 573 { 574 if (rtp->level == 10) { 575 switch (rtp->algorithm) { 576 case ALGORITHM_RAID10_DEFAULT: 577 case ALGORITHM_RAID10_NEAR: 578 return __is_raid10_near(layout); 579 case ALGORITHM_RAID10_OFFSET: 580 return __is_raid10_offset(layout); 581 case ALGORITHM_RAID10_FAR: 582 return __is_raid10_far(layout); 583 default: 584 break; 585 } 586 } 587 588 return false; 589 } 590 591 /* Return raid_type for @name */ 592 static struct raid_type *get_raid_type(const char *name) 593 { 594 struct raid_type *rtp = raid_types + ARRAY_SIZE(raid_types); 595 596 while (rtp-- > raid_types) 597 if (!strcasecmp(rtp->name, name)) 598 return rtp; 599 600 return NULL; 601 } 602 603 /* Return raid_type for @name based derived from @level and @layout */ 604 static struct raid_type *get_raid_type_by_ll(const int level, const int layout) 605 { 606 struct raid_type *rtp = raid_types + ARRAY_SIZE(raid_types); 607 608 while (rtp-- > raid_types) { 609 /* RAID10 special checks based on @layout flags/properties */ 610 if (rtp->level == level && 611 (__got_raid10(rtp, layout) || rtp->algorithm == layout)) 612 return rtp; 613 } 614 615 return NULL; 616 } 617 618 /* 619 * Conditionally change bdev capacity of @rs 620 * in case of a disk add/remove reshape 621 */ 622 static void rs_set_capacity(struct raid_set *rs) 623 { 624 struct mddev *mddev = &rs->md; 625 struct md_rdev *rdev; 626 struct gendisk *gendisk = dm_disk(dm_table_get_md(rs->ti->table)); 627 628 /* 629 * raid10 sets rdev->sector to the device size, which 630 * is unintended in case of out-of-place reshaping 631 */ 632 rdev_for_each(rdev, mddev) 633 rdev->sectors = mddev->dev_sectors; 634 635 set_capacity(gendisk, mddev->array_sectors); 636 revalidate_disk(gendisk); 637 } 638 639 /* 640 * Set the mddev properties in @rs to the current 641 * ones retrieved from the freshest superblock 642 */ 643 static void rs_set_cur(struct raid_set *rs) 644 { 645 struct mddev *mddev = &rs->md; 646 647 mddev->new_level = mddev->level; 648 mddev->new_layout = mddev->layout; 649 mddev->new_chunk_sectors = mddev->chunk_sectors; 650 } 651 652 /* 653 * Set the mddev properties in @rs to the new 654 * ones requested by the ctr 655 */ 656 static void rs_set_new(struct raid_set *rs) 657 { 658 struct mddev *mddev = &rs->md; 659 660 mddev->level = mddev->new_level; 661 mddev->layout = mddev->new_layout; 662 mddev->chunk_sectors = mddev->new_chunk_sectors; 663 mddev->raid_disks = rs->raid_disks; 664 mddev->delta_disks = 0; 665 } 666 667 static struct raid_set *raid_set_alloc(struct dm_target *ti, struct raid_type *raid_type, 668 unsigned int raid_devs) 669 { 670 unsigned int i; 671 struct raid_set *rs; 672 673 if (raid_devs <= raid_type->parity_devs) { 674 ti->error = "Insufficient number of devices"; 675 return ERR_PTR(-EINVAL); 676 } 677 678 rs = kzalloc(sizeof(*rs) + raid_devs * sizeof(rs->dev[0]), GFP_KERNEL); 679 if (!rs) { 680 ti->error = "Cannot allocate raid context"; 681 return ERR_PTR(-ENOMEM); 682 } 683 684 mddev_init(&rs->md); 685 686 rs->raid_disks = raid_devs; 687 rs->delta_disks = 0; 688 689 rs->ti = ti; 690 rs->raid_type = raid_type; 691 rs->stripe_cache_entries = 256; 692 rs->md.raid_disks = raid_devs; 693 rs->md.level = raid_type->level; 694 rs->md.new_level = rs->md.level; 695 rs->md.layout = raid_type->algorithm; 696 rs->md.new_layout = rs->md.layout; 697 rs->md.delta_disks = 0; 698 rs->md.recovery_cp = MaxSector; 699 700 for (i = 0; i < raid_devs; i++) 701 md_rdev_init(&rs->dev[i].rdev); 702 703 /* 704 * Remaining items to be initialized by further RAID params: 705 * rs->md.persistent 706 * rs->md.external 707 * rs->md.chunk_sectors 708 * rs->md.new_chunk_sectors 709 * rs->md.dev_sectors 710 */ 711 712 return rs; 713 } 714 715 static void raid_set_free(struct raid_set *rs) 716 { 717 int i; 718 719 for (i = 0; i < rs->raid_disks; i++) { 720 if (rs->dev[i].meta_dev) 721 dm_put_device(rs->ti, rs->dev[i].meta_dev); 722 md_rdev_clear(&rs->dev[i].rdev); 723 if (rs->dev[i].data_dev) 724 dm_put_device(rs->ti, rs->dev[i].data_dev); 725 } 726 727 kfree(rs); 728 } 729 730 /* 731 * For every device we have two words 732 * <meta_dev>: meta device name or '-' if missing 733 * <data_dev>: data device name or '-' if missing 734 * 735 * The following are permitted: 736 * - - 737 * - <data_dev> 738 * <meta_dev> <data_dev> 739 * 740 * The following is not allowed: 741 * <meta_dev> - 742 * 743 * This code parses those words. If there is a failure, 744 * the caller must use raid_set_free() to unwind the operations. 745 */ 746 static int parse_dev_params(struct raid_set *rs, struct dm_arg_set *as) 747 { 748 int i; 749 int rebuild = 0; 750 int metadata_available = 0; 751 int r = 0; 752 const char *arg; 753 754 /* Put off the number of raid devices argument to get to dev pairs */ 755 arg = dm_shift_arg(as); 756 if (!arg) 757 return -EINVAL; 758 759 for (i = 0; i < rs->raid_disks; i++) { 760 rs->dev[i].rdev.raid_disk = i; 761 762 rs->dev[i].meta_dev = NULL; 763 rs->dev[i].data_dev = NULL; 764 765 /* 766 * There are no offsets, since there is a separate device 767 * for data and metadata. 768 */ 769 rs->dev[i].rdev.data_offset = 0; 770 rs->dev[i].rdev.mddev = &rs->md; 771 772 arg = dm_shift_arg(as); 773 if (!arg) 774 return -EINVAL; 775 776 if (strcmp(arg, "-")) { 777 r = dm_get_device(rs->ti, arg, dm_table_get_mode(rs->ti->table), 778 &rs->dev[i].meta_dev); 779 if (r) { 780 rs->ti->error = "RAID metadata device lookup failure"; 781 return r; 782 } 783 784 rs->dev[i].rdev.sb_page = alloc_page(GFP_KERNEL); 785 if (!rs->dev[i].rdev.sb_page) { 786 rs->ti->error = "Failed to allocate superblock page"; 787 return -ENOMEM; 788 } 789 } 790 791 arg = dm_shift_arg(as); 792 if (!arg) 793 return -EINVAL; 794 795 if (!strcmp(arg, "-")) { 796 if (!test_bit(In_sync, &rs->dev[i].rdev.flags) && 797 (!rs->dev[i].rdev.recovery_offset)) { 798 rs->ti->error = "Drive designated for rebuild not specified"; 799 return -EINVAL; 800 } 801 802 if (rs->dev[i].meta_dev) { 803 rs->ti->error = "No data device supplied with metadata device"; 804 return -EINVAL; 805 } 806 807 continue; 808 } 809 810 r = dm_get_device(rs->ti, arg, dm_table_get_mode(rs->ti->table), 811 &rs->dev[i].data_dev); 812 if (r) { 813 rs->ti->error = "RAID device lookup failure"; 814 return r; 815 } 816 817 if (rs->dev[i].meta_dev) { 818 metadata_available = 1; 819 rs->dev[i].rdev.meta_bdev = rs->dev[i].meta_dev->bdev; 820 } 821 rs->dev[i].rdev.bdev = rs->dev[i].data_dev->bdev; 822 list_add_tail(&rs->dev[i].rdev.same_set, &rs->md.disks); 823 if (!test_bit(In_sync, &rs->dev[i].rdev.flags)) 824 rebuild++; 825 } 826 827 if (metadata_available) { 828 rs->md.external = 0; 829 rs->md.persistent = 1; 830 rs->md.major_version = 2; 831 } else if (rebuild && !rs->md.recovery_cp) { 832 /* 833 * Without metadata, we will not be able to tell if the array 834 * is in-sync or not - we must assume it is not. Therefore, 835 * it is impossible to rebuild a drive. 836 * 837 * Even if there is metadata, the on-disk information may 838 * indicate that the array is not in-sync and it will then 839 * fail at that time. 840 * 841 * User could specify 'nosync' option if desperate. 842 */ 843 rs->ti->error = "Unable to rebuild drive while array is not in-sync"; 844 return -EINVAL; 845 } 846 847 return 0; 848 } 849 850 /* 851 * validate_region_size 852 * @rs 853 * @region_size: region size in sectors. If 0, pick a size (4MiB default). 854 * 855 * Set rs->md.bitmap_info.chunksize (which really refers to 'region size'). 856 * Ensure that (ti->len/region_size < 2^21) - required by MD bitmap. 857 * 858 * Returns: 0 on success, -EINVAL on failure. 859 */ 860 static int validate_region_size(struct raid_set *rs, unsigned long region_size) 861 { 862 unsigned long min_region_size = rs->ti->len / (1 << 21); 863 864 if (!region_size) { 865 /* 866 * Choose a reasonable default. All figures in sectors. 867 */ 868 if (min_region_size > (1 << 13)) { 869 /* If not a power of 2, make it the next power of 2 */ 870 region_size = roundup_pow_of_two(min_region_size); 871 DMINFO("Choosing default region size of %lu sectors", 872 region_size); 873 } else { 874 DMINFO("Choosing default region size of 4MiB"); 875 region_size = 1 << 13; /* sectors */ 876 } 877 } else { 878 /* 879 * Validate user-supplied value. 880 */ 881 if (region_size > rs->ti->len) { 882 rs->ti->error = "Supplied region size is too large"; 883 return -EINVAL; 884 } 885 886 if (region_size < min_region_size) { 887 DMERR("Supplied region_size (%lu sectors) below minimum (%lu)", 888 region_size, min_region_size); 889 rs->ti->error = "Supplied region size is too small"; 890 return -EINVAL; 891 } 892 893 if (!is_power_of_2(region_size)) { 894 rs->ti->error = "Region size is not a power of 2"; 895 return -EINVAL; 896 } 897 898 if (region_size < rs->md.chunk_sectors) { 899 rs->ti->error = "Region size is smaller than the chunk size"; 900 return -EINVAL; 901 } 902 } 903 904 /* 905 * Convert sectors to bytes. 906 */ 907 rs->md.bitmap_info.chunksize = to_bytes(region_size); 908 909 return 0; 910 } 911 912 /* 913 * validate_raid_redundancy 914 * @rs 915 * 916 * Determine if there are enough devices in the array that haven't 917 * failed (or are being rebuilt) to form a usable array. 918 * 919 * Returns: 0 on success, -EINVAL on failure. 920 */ 921 static int validate_raid_redundancy(struct raid_set *rs) 922 { 923 unsigned int i, rebuild_cnt = 0; 924 unsigned int rebuilds_per_group = 0, copies; 925 unsigned int group_size, last_group_start; 926 927 for (i = 0; i < rs->md.raid_disks; i++) 928 if (!test_bit(In_sync, &rs->dev[i].rdev.flags) || 929 !rs->dev[i].rdev.sb_page) 930 rebuild_cnt++; 931 932 switch (rs->raid_type->level) { 933 case 1: 934 if (rebuild_cnt >= rs->md.raid_disks) 935 goto too_many; 936 break; 937 case 4: 938 case 5: 939 case 6: 940 if (rebuild_cnt > rs->raid_type->parity_devs) 941 goto too_many; 942 break; 943 case 10: 944 copies = raid10_md_layout_to_copies(rs->md.new_layout); 945 if (rebuild_cnt < copies) 946 break; 947 948 /* 949 * It is possible to have a higher rebuild count for RAID10, 950 * as long as the failed devices occur in different mirror 951 * groups (i.e. different stripes). 952 * 953 * When checking "near" format, make sure no adjacent devices 954 * have failed beyond what can be handled. In addition to the 955 * simple case where the number of devices is a multiple of the 956 * number of copies, we must also handle cases where the number 957 * of devices is not a multiple of the number of copies. 958 * E.g. dev1 dev2 dev3 dev4 dev5 959 * A A B B C 960 * C D D E E 961 */ 962 if (__is_raid10_near(rs->md.new_layout)) { 963 for (i = 0; i < rs->md.raid_disks; i++) { 964 if (!(i % copies)) 965 rebuilds_per_group = 0; 966 if ((!rs->dev[i].rdev.sb_page || 967 !test_bit(In_sync, &rs->dev[i].rdev.flags)) && 968 (++rebuilds_per_group >= copies)) 969 goto too_many; 970 } 971 break; 972 } 973 974 /* 975 * When checking "far" and "offset" formats, we need to ensure 976 * that the device that holds its copy is not also dead or 977 * being rebuilt. (Note that "far" and "offset" formats only 978 * support two copies right now. These formats also only ever 979 * use the 'use_far_sets' variant.) 980 * 981 * This check is somewhat complicated by the need to account 982 * for arrays that are not a multiple of (far) copies. This 983 * results in the need to treat the last (potentially larger) 984 * set differently. 985 */ 986 group_size = (rs->md.raid_disks / copies); 987 last_group_start = (rs->md.raid_disks / group_size) - 1; 988 last_group_start *= group_size; 989 for (i = 0; i < rs->md.raid_disks; i++) { 990 if (!(i % copies) && !(i > last_group_start)) 991 rebuilds_per_group = 0; 992 if ((!rs->dev[i].rdev.sb_page || 993 !test_bit(In_sync, &rs->dev[i].rdev.flags)) && 994 (++rebuilds_per_group >= copies)) 995 goto too_many; 996 } 997 break; 998 default: 999 if (rebuild_cnt) 1000 return -EINVAL; 1001 } 1002 1003 return 0; 1004 1005 too_many: 1006 return -EINVAL; 1007 } 1008 1009 /* 1010 * Possible arguments are... 1011 * <chunk_size> [optional_args] 1012 * 1013 * Argument definitions 1014 * <chunk_size> The number of sectors per disk that 1015 * will form the "stripe" 1016 * [[no]sync] Force or prevent recovery of the 1017 * entire array 1018 * [rebuild <idx>] Rebuild the drive indicated by the index 1019 * [daemon_sleep <ms>] Time between bitmap daemon work to 1020 * clear bits 1021 * [min_recovery_rate <kB/sec/disk>] Throttle RAID initialization 1022 * [max_recovery_rate <kB/sec/disk>] Throttle RAID initialization 1023 * [write_mostly <idx>] Indicate a write mostly drive via index 1024 * [max_write_behind <sectors>] See '-write-behind=' (man mdadm) 1025 * [stripe_cache <sectors>] Stripe cache size for higher RAIDs 1026 * [region_size <sectors>] Defines granularity of bitmap 1027 * 1028 * RAID10-only options: 1029 * [raid10_copies <# copies>] Number of copies. (Default: 2) 1030 * [raid10_format <near|far|offset>] Layout algorithm. (Default: near) 1031 */ 1032 static int parse_raid_params(struct raid_set *rs, struct dm_arg_set *as, 1033 unsigned int num_raid_params) 1034 { 1035 int value, raid10_format = ALGORITHM_RAID10_DEFAULT; 1036 unsigned int raid10_copies = 2; 1037 unsigned int i, write_mostly = 0; 1038 unsigned int region_size = 0; 1039 sector_t max_io_len; 1040 const char *arg, *key; 1041 struct raid_dev *rd; 1042 struct raid_type *rt = rs->raid_type; 1043 1044 arg = dm_shift_arg(as); 1045 num_raid_params--; /* Account for chunk_size argument */ 1046 1047 if (kstrtoint(arg, 10, &value) < 0) { 1048 rs->ti->error = "Bad numerical argument given for chunk_size"; 1049 return -EINVAL; 1050 } 1051 1052 /* 1053 * First, parse the in-order required arguments 1054 * "chunk_size" is the only argument of this type. 1055 */ 1056 if (rt_is_raid1(rt)) { 1057 if (value) 1058 DMERR("Ignoring chunk size parameter for RAID 1"); 1059 value = 0; 1060 } else if (!is_power_of_2(value)) { 1061 rs->ti->error = "Chunk size must be a power of 2"; 1062 return -EINVAL; 1063 } else if (value < 8) { 1064 rs->ti->error = "Chunk size value is too small"; 1065 return -EINVAL; 1066 } 1067 1068 rs->md.new_chunk_sectors = rs->md.chunk_sectors = value; 1069 1070 /* 1071 * We set each individual device as In_sync with a completed 1072 * 'recovery_offset'. If there has been a device failure or 1073 * replacement then one of the following cases applies: 1074 * 1075 * 1) User specifies 'rebuild'. 1076 * - Device is reset when param is read. 1077 * 2) A new device is supplied. 1078 * - No matching superblock found, resets device. 1079 * 3) Device failure was transient and returns on reload. 1080 * - Failure noticed, resets device for bitmap replay. 1081 * 4) Device hadn't completed recovery after previous failure. 1082 * - Superblock is read and overrides recovery_offset. 1083 * 1084 * What is found in the superblocks of the devices is always 1085 * authoritative, unless 'rebuild' or '[no]sync' was specified. 1086 */ 1087 for (i = 0; i < rs->raid_disks; i++) { 1088 set_bit(In_sync, &rs->dev[i].rdev.flags); 1089 rs->dev[i].rdev.recovery_offset = MaxSector; 1090 } 1091 1092 /* 1093 * Second, parse the unordered optional arguments 1094 */ 1095 for (i = 0; i < num_raid_params; i++) { 1096 key = dm_shift_arg(as); 1097 if (!key) { 1098 rs->ti->error = "Not enough raid parameters given"; 1099 return -EINVAL; 1100 } 1101 1102 if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_NOSYNC))) { 1103 if (test_and_set_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) { 1104 rs->ti->error = "Only one 'nosync' argument allowed"; 1105 return -EINVAL; 1106 } 1107 continue; 1108 } 1109 if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_SYNC))) { 1110 if (test_and_set_bit(__CTR_FLAG_SYNC, &rs->ctr_flags)) { 1111 rs->ti->error = "Only one 'sync' argument allowed"; 1112 return -EINVAL; 1113 } 1114 continue; 1115 } 1116 if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_USE_NEAR_SETS))) { 1117 if (test_and_set_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags)) { 1118 rs->ti->error = "Only one 'raid10_use_new_sets' argument allowed"; 1119 return -EINVAL; 1120 } 1121 continue; 1122 } 1123 1124 arg = dm_shift_arg(as); 1125 i++; /* Account for the argument pairs */ 1126 if (!arg) { 1127 rs->ti->error = "Wrong number of raid parameters given"; 1128 return -EINVAL; 1129 } 1130 1131 /* 1132 * Parameters that take a string value are checked here. 1133 */ 1134 1135 if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_FORMAT))) { 1136 if (test_and_set_bit(__CTR_FLAG_RAID10_FORMAT, &rs->ctr_flags)) { 1137 rs->ti->error = "Only one 'raid10_format' argument pair allowed"; 1138 return -EINVAL; 1139 } 1140 if (!rt_is_raid10(rt)) { 1141 rs->ti->error = "'raid10_format' is an invalid parameter for this RAID type"; 1142 return -EINVAL; 1143 } 1144 raid10_format = raid10_name_to_format(arg); 1145 if (raid10_format < 0) { 1146 rs->ti->error = "Invalid 'raid10_format' value given"; 1147 return raid10_format; 1148 } 1149 continue; 1150 } 1151 1152 if (kstrtoint(arg, 10, &value) < 0) { 1153 rs->ti->error = "Bad numerical argument given in raid params"; 1154 return -EINVAL; 1155 } 1156 1157 if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_REBUILD))) { 1158 /* 1159 * "rebuild" is being passed in by userspace to provide 1160 * indexes of replaced devices and to set up additional 1161 * devices on raid level takeover. 1162 */ 1163 if (!__within_range(value, 0, rs->raid_disks - 1)) { 1164 rs->ti->error = "Invalid rebuild index given"; 1165 return -EINVAL; 1166 } 1167 1168 if (test_and_set_bit(value, (void *) rs->rebuild_disks)) { 1169 rs->ti->error = "rebuild for this index already given"; 1170 return -EINVAL; 1171 } 1172 1173 rd = rs->dev + value; 1174 clear_bit(In_sync, &rd->rdev.flags); 1175 clear_bit(Faulty, &rd->rdev.flags); 1176 rd->rdev.recovery_offset = 0; 1177 set_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags); 1178 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_WRITE_MOSTLY))) { 1179 if (!rt_is_raid1(rt)) { 1180 rs->ti->error = "write_mostly option is only valid for RAID1"; 1181 return -EINVAL; 1182 } 1183 1184 if (!__within_range(value, 0, rs->md.raid_disks - 1)) { 1185 rs->ti->error = "Invalid write_mostly index given"; 1186 return -EINVAL; 1187 } 1188 1189 write_mostly++; 1190 set_bit(WriteMostly, &rs->dev[value].rdev.flags); 1191 set_bit(__CTR_FLAG_WRITE_MOSTLY, &rs->ctr_flags); 1192 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MAX_WRITE_BEHIND))) { 1193 if (!rt_is_raid1(rt)) { 1194 rs->ti->error = "max_write_behind option is only valid for RAID1"; 1195 return -EINVAL; 1196 } 1197 1198 if (test_and_set_bit(__CTR_FLAG_MAX_WRITE_BEHIND, &rs->ctr_flags)) { 1199 rs->ti->error = "Only one max_write_behind argument pair allowed"; 1200 return -EINVAL; 1201 } 1202 1203 /* 1204 * In device-mapper, we specify things in sectors, but 1205 * MD records this value in kB 1206 */ 1207 value /= 2; 1208 if (value > COUNTER_MAX) { 1209 rs->ti->error = "Max write-behind limit out of range"; 1210 return -EINVAL; 1211 } 1212 1213 rs->md.bitmap_info.max_write_behind = value; 1214 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DAEMON_SLEEP))) { 1215 if (test_and_set_bit(__CTR_FLAG_DAEMON_SLEEP, &rs->ctr_flags)) { 1216 rs->ti->error = "Only one daemon_sleep argument pair allowed"; 1217 return -EINVAL; 1218 } 1219 if (!value || (value > MAX_SCHEDULE_TIMEOUT)) { 1220 rs->ti->error = "daemon sleep period out of range"; 1221 return -EINVAL; 1222 } 1223 rs->md.bitmap_info.daemon_sleep = value; 1224 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DATA_OFFSET))) { 1225 /* Userspace passes new data_offset after having extended the the data image LV */ 1226 if (test_and_set_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags)) { 1227 rs->ti->error = "Only one data_offset argument pair allowed"; 1228 return -EINVAL; 1229 } 1230 /* Ensure sensible data offset */ 1231 if (value < 0 || 1232 (value && (value < MIN_FREE_RESHAPE_SPACE || value % to_sector(PAGE_SIZE)))) { 1233 rs->ti->error = "Bogus data_offset value"; 1234 return -EINVAL; 1235 } 1236 rs->data_offset = value; 1237 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DELTA_DISKS))) { 1238 /* Define the +/-# of disks to add to/remove from the given raid set */ 1239 if (test_and_set_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags)) { 1240 rs->ti->error = "Only one delta_disks argument pair allowed"; 1241 return -EINVAL; 1242 } 1243 /* Ensure MAX_RAID_DEVICES and raid type minimal_devs! */ 1244 if (!__within_range(abs(value), 1, MAX_RAID_DEVICES - rt->minimal_devs)) { 1245 rs->ti->error = "Too many delta_disk requested"; 1246 return -EINVAL; 1247 } 1248 1249 rs->delta_disks = value; 1250 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_STRIPE_CACHE))) { 1251 if (test_and_set_bit(__CTR_FLAG_STRIPE_CACHE, &rs->ctr_flags)) { 1252 rs->ti->error = "Only one stripe_cache argument pair allowed"; 1253 return -EINVAL; 1254 } 1255 1256 if (!rt_is_raid456(rt)) { 1257 rs->ti->error = "Inappropriate argument: stripe_cache"; 1258 return -EINVAL; 1259 } 1260 1261 rs->stripe_cache_entries = value; 1262 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MIN_RECOVERY_RATE))) { 1263 if (test_and_set_bit(__CTR_FLAG_MIN_RECOVERY_RATE, &rs->ctr_flags)) { 1264 rs->ti->error = "Only one min_recovery_rate argument pair allowed"; 1265 return -EINVAL; 1266 } 1267 if (value > INT_MAX) { 1268 rs->ti->error = "min_recovery_rate out of range"; 1269 return -EINVAL; 1270 } 1271 rs->md.sync_speed_min = (int)value; 1272 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MAX_RECOVERY_RATE))) { 1273 if (test_and_set_bit(__CTR_FLAG_MAX_RECOVERY_RATE, &rs->ctr_flags)) { 1274 rs->ti->error = "Only one max_recovery_rate argument pair allowed"; 1275 return -EINVAL; 1276 } 1277 if (value > INT_MAX) { 1278 rs->ti->error = "max_recovery_rate out of range"; 1279 return -EINVAL; 1280 } 1281 rs->md.sync_speed_max = (int)value; 1282 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_REGION_SIZE))) { 1283 if (test_and_set_bit(__CTR_FLAG_REGION_SIZE, &rs->ctr_flags)) { 1284 rs->ti->error = "Only one region_size argument pair allowed"; 1285 return -EINVAL; 1286 } 1287 1288 region_size = value; 1289 rs->requested_bitmap_chunk_sectors = value; 1290 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_COPIES))) { 1291 if (test_and_set_bit(__CTR_FLAG_RAID10_COPIES, &rs->ctr_flags)) { 1292 rs->ti->error = "Only one raid10_copies argument pair allowed"; 1293 return -EINVAL; 1294 } 1295 1296 if (!__within_range(value, 2, rs->md.raid_disks)) { 1297 rs->ti->error = "Bad value for 'raid10_copies'"; 1298 return -EINVAL; 1299 } 1300 1301 raid10_copies = value; 1302 } else { 1303 DMERR("Unable to parse RAID parameter: %s", key); 1304 rs->ti->error = "Unable to parse RAID parameter"; 1305 return -EINVAL; 1306 } 1307 } 1308 1309 if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags) && 1310 test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) { 1311 rs->ti->error = "sync and nosync are mutually exclusive"; 1312 return -EINVAL; 1313 } 1314 1315 if (test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags) && 1316 (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags) || 1317 test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags))) { 1318 rs->ti->error = "sync/nosync and rebuild are mutually exclusive"; 1319 return -EINVAL; 1320 } 1321 1322 if (write_mostly >= rs->md.raid_disks) { 1323 rs->ti->error = "Can't set all raid1 devices to write_mostly"; 1324 return -EINVAL; 1325 } 1326 1327 if (validate_region_size(rs, region_size)) 1328 return -EINVAL; 1329 1330 if (rs->md.chunk_sectors) 1331 max_io_len = rs->md.chunk_sectors; 1332 else 1333 max_io_len = region_size; 1334 1335 if (dm_set_target_max_io_len(rs->ti, max_io_len)) 1336 return -EINVAL; 1337 1338 if (rt_is_raid10(rt)) { 1339 if (raid10_copies > rs->md.raid_disks) { 1340 rs->ti->error = "Not enough devices to satisfy specification"; 1341 return -EINVAL; 1342 } 1343 1344 rs->md.new_layout = raid10_format_to_md_layout(rs, raid10_format, raid10_copies); 1345 if (rs->md.new_layout < 0) { 1346 rs->ti->error = "Error getting raid10 format"; 1347 return rs->md.new_layout; 1348 } 1349 1350 rt = get_raid_type_by_ll(10, rs->md.new_layout); 1351 if (!rt) { 1352 rs->ti->error = "Failed to recognize new raid10 layout"; 1353 return -EINVAL; 1354 } 1355 1356 if ((rt->algorithm == ALGORITHM_RAID10_DEFAULT || 1357 rt->algorithm == ALGORITHM_RAID10_NEAR) && 1358 test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags)) { 1359 rs->ti->error = "RAID10 format 'near' and 'raid10_use_near_sets' are incompatible"; 1360 return -EINVAL; 1361 } 1362 } 1363 1364 rs->raid10_copies = raid10_copies; 1365 1366 /* Assume there are no metadata devices until the drives are parsed */ 1367 rs->md.persistent = 0; 1368 rs->md.external = 1; 1369 1370 /* Check, if any invalid ctr arguments have been passed in for the raid level */ 1371 return rs_check_for_valid_flags(rs); 1372 } 1373 1374 /* Set raid4/5/6 cache size */ 1375 static int rs_set_raid456_stripe_cache(struct raid_set *rs) 1376 { 1377 int r; 1378 struct r5conf *conf; 1379 struct mddev *mddev = &rs->md; 1380 uint32_t min_stripes = max(mddev->chunk_sectors, mddev->new_chunk_sectors) / 2; 1381 uint32_t nr_stripes = rs->stripe_cache_entries; 1382 1383 if (!rt_is_raid456(rs->raid_type)) { 1384 rs->ti->error = "Inappropriate raid level; cannot change stripe_cache size"; 1385 return -EINVAL; 1386 } 1387 1388 if (nr_stripes < min_stripes) { 1389 DMINFO("Adjusting requested %u stripe cache entries to %u to suit stripe size", 1390 nr_stripes, min_stripes); 1391 nr_stripes = min_stripes; 1392 } 1393 1394 conf = mddev->private; 1395 if (!conf) { 1396 rs->ti->error = "Cannot change stripe_cache size on inactive RAID set"; 1397 return -EINVAL; 1398 } 1399 1400 /* Try setting number of stripes in raid456 stripe cache */ 1401 if (conf->min_nr_stripes != nr_stripes) { 1402 r = raid5_set_cache_size(mddev, nr_stripes); 1403 if (r) { 1404 rs->ti->error = "Failed to set raid4/5/6 stripe cache size"; 1405 return r; 1406 } 1407 1408 DMINFO("%u stripe cache entries", nr_stripes); 1409 } 1410 1411 return 0; 1412 } 1413 1414 /* Return # of data stripes as kept in mddev as of @rs (i.e. as of superblock) */ 1415 static unsigned int mddev_data_stripes(struct raid_set *rs) 1416 { 1417 return rs->md.raid_disks - rs->raid_type->parity_devs; 1418 } 1419 1420 /* Return # of data stripes of @rs (i.e. as of ctr) */ 1421 static unsigned int rs_data_stripes(struct raid_set *rs) 1422 { 1423 return rs->raid_disks - rs->raid_type->parity_devs; 1424 } 1425 1426 /* Calculate the sectors per device and per array used for @rs */ 1427 static int rs_set_dev_and_array_sectors(struct raid_set *rs, bool use_mddev) 1428 { 1429 int delta_disks; 1430 unsigned int data_stripes; 1431 struct mddev *mddev = &rs->md; 1432 struct md_rdev *rdev; 1433 sector_t array_sectors = rs->ti->len, dev_sectors = rs->ti->len; 1434 1435 if (use_mddev) { 1436 delta_disks = mddev->delta_disks; 1437 data_stripes = mddev_data_stripes(rs); 1438 } else { 1439 delta_disks = rs->delta_disks; 1440 data_stripes = rs_data_stripes(rs); 1441 } 1442 1443 /* Special raid1 case w/o delta_disks support (yet) */ 1444 if (rt_is_raid1(rs->raid_type)) 1445 ; 1446 else if (rt_is_raid10(rs->raid_type)) { 1447 if (rs->raid10_copies < 2 || 1448 delta_disks < 0) { 1449 rs->ti->error = "Bogus raid10 data copies or delta disks"; 1450 return -EINVAL; 1451 } 1452 1453 dev_sectors *= rs->raid10_copies; 1454 if (sector_div(dev_sectors, data_stripes)) 1455 goto bad; 1456 1457 array_sectors = (data_stripes + delta_disks) * dev_sectors; 1458 if (sector_div(array_sectors, rs->raid10_copies)) 1459 goto bad; 1460 1461 } else if (sector_div(dev_sectors, data_stripes)) 1462 goto bad; 1463 1464 else 1465 /* Striped layouts */ 1466 array_sectors = (data_stripes + delta_disks) * dev_sectors; 1467 1468 rdev_for_each(rdev, mddev) 1469 rdev->sectors = dev_sectors; 1470 1471 mddev->array_sectors = array_sectors; 1472 mddev->dev_sectors = dev_sectors; 1473 1474 return 0; 1475 bad: 1476 rs->ti->error = "Target length not divisible by number of data devices"; 1477 return -EINVAL; 1478 } 1479 1480 /* Setup recovery on @rs */ 1481 static void __rs_setup_recovery(struct raid_set *rs, sector_t dev_sectors) 1482 { 1483 /* raid0 does not recover */ 1484 if (rs_is_raid0(rs)) 1485 rs->md.recovery_cp = MaxSector; 1486 /* 1487 * A raid6 set has to be recovered either 1488 * completely or for the grown part to 1489 * ensure proper parity and Q-Syndrome 1490 */ 1491 else if (rs_is_raid6(rs)) 1492 rs->md.recovery_cp = dev_sectors; 1493 /* 1494 * Other raid set types may skip recovery 1495 * depending on the 'nosync' flag. 1496 */ 1497 else 1498 rs->md.recovery_cp = test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags) 1499 ? MaxSector : dev_sectors; 1500 } 1501 1502 /* Setup recovery on @rs based on raid type, device size and 'nosync' flag */ 1503 static void rs_setup_recovery(struct raid_set *rs, sector_t dev_sectors) 1504 { 1505 if (!dev_sectors) 1506 /* New raid set or 'sync' flag provided */ 1507 __rs_setup_recovery(rs, 0); 1508 else if (dev_sectors == MaxSector) 1509 /* Prevent recovery */ 1510 __rs_setup_recovery(rs, MaxSector); 1511 else if (rs->dev[0].rdev.sectors < dev_sectors) 1512 /* Grown raid set */ 1513 __rs_setup_recovery(rs, rs->dev[0].rdev.sectors); 1514 else 1515 __rs_setup_recovery(rs, MaxSector); 1516 } 1517 1518 static void do_table_event(struct work_struct *ws) 1519 { 1520 struct raid_set *rs = container_of(ws, struct raid_set, md.event_work); 1521 1522 smp_rmb(); /* Make sure we access most actual mddev properties */ 1523 if (!rs_is_reshaping(rs)) 1524 rs_set_capacity(rs); 1525 dm_table_event(rs->ti->table); 1526 } 1527 1528 static int raid_is_congested(struct dm_target_callbacks *cb, int bits) 1529 { 1530 struct raid_set *rs = container_of(cb, struct raid_set, callbacks); 1531 1532 return mddev_congested(&rs->md, bits); 1533 } 1534 1535 /* 1536 * Make sure a valid takover (level switch) is being requested on @rs 1537 * 1538 * Conversions of raid sets from one MD personality to another 1539 * have to conform to restrictions which are enforced here. 1540 */ 1541 static int rs_check_takeover(struct raid_set *rs) 1542 { 1543 struct mddev *mddev = &rs->md; 1544 unsigned int near_copies; 1545 1546 if (rs->md.degraded) { 1547 rs->ti->error = "Can't takeover degraded raid set"; 1548 return -EPERM; 1549 } 1550 1551 if (rs_is_reshaping(rs)) { 1552 rs->ti->error = "Can't takeover reshaping raid set"; 1553 return -EPERM; 1554 } 1555 1556 switch (mddev->level) { 1557 case 0: 1558 /* raid0 -> raid1/5 with one disk */ 1559 if ((mddev->new_level == 1 || mddev->new_level == 5) && 1560 mddev->raid_disks == 1) 1561 return 0; 1562 1563 /* raid0 -> raid10 */ 1564 if (mddev->new_level == 10 && 1565 !(rs->raid_disks % mddev->raid_disks)) 1566 return 0; 1567 1568 /* raid0 with multiple disks -> raid4/5/6 */ 1569 if (__within_range(mddev->new_level, 4, 6) && 1570 mddev->new_layout == ALGORITHM_PARITY_N && 1571 mddev->raid_disks > 1) 1572 return 0; 1573 1574 break; 1575 1576 case 10: 1577 /* Can't takeover raid10_offset! */ 1578 if (__is_raid10_offset(mddev->layout)) 1579 break; 1580 1581 near_copies = __raid10_near_copies(mddev->layout); 1582 1583 /* raid10* -> raid0 */ 1584 if (mddev->new_level == 0) { 1585 /* Can takeover raid10_near with raid disks divisable by data copies! */ 1586 if (near_copies > 1 && 1587 !(mddev->raid_disks % near_copies)) { 1588 mddev->raid_disks /= near_copies; 1589 mddev->delta_disks = mddev->raid_disks; 1590 return 0; 1591 } 1592 1593 /* Can takeover raid10_far */ 1594 if (near_copies == 1 && 1595 __raid10_far_copies(mddev->layout) > 1) 1596 return 0; 1597 1598 break; 1599 } 1600 1601 /* raid10_{near,far} -> raid1 */ 1602 if (mddev->new_level == 1 && 1603 max(near_copies, __raid10_far_copies(mddev->layout)) == mddev->raid_disks) 1604 return 0; 1605 1606 /* raid10_{near,far} with 2 disks -> raid4/5 */ 1607 if (__within_range(mddev->new_level, 4, 5) && 1608 mddev->raid_disks == 2) 1609 return 0; 1610 break; 1611 1612 case 1: 1613 /* raid1 with 2 disks -> raid4/5 */ 1614 if (__within_range(mddev->new_level, 4, 5) && 1615 mddev->raid_disks == 2) { 1616 mddev->degraded = 1; 1617 return 0; 1618 } 1619 1620 /* raid1 -> raid0 */ 1621 if (mddev->new_level == 0 && 1622 mddev->raid_disks == 1) 1623 return 0; 1624 1625 /* raid1 -> raid10 */ 1626 if (mddev->new_level == 10) 1627 return 0; 1628 break; 1629 1630 case 4: 1631 /* raid4 -> raid0 */ 1632 if (mddev->new_level == 0) 1633 return 0; 1634 1635 /* raid4 -> raid1/5 with 2 disks */ 1636 if ((mddev->new_level == 1 || mddev->new_level == 5) && 1637 mddev->raid_disks == 2) 1638 return 0; 1639 1640 /* raid4 -> raid5/6 with parity N */ 1641 if (__within_range(mddev->new_level, 5, 6) && 1642 mddev->layout == ALGORITHM_PARITY_N) 1643 return 0; 1644 break; 1645 1646 case 5: 1647 /* raid5 with parity N -> raid0 */ 1648 if (mddev->new_level == 0 && 1649 mddev->layout == ALGORITHM_PARITY_N) 1650 return 0; 1651 1652 /* raid5 with parity N -> raid4 */ 1653 if (mddev->new_level == 4 && 1654 mddev->layout == ALGORITHM_PARITY_N) 1655 return 0; 1656 1657 /* raid5 with 2 disks -> raid1/4/10 */ 1658 if ((mddev->new_level == 1 || mddev->new_level == 4 || mddev->new_level == 10) && 1659 mddev->raid_disks == 2) 1660 return 0; 1661 1662 /* raid5_* -> raid6_*_6 with Q-Syndrome N (e.g. raid5_ra -> raid6_ra_6 */ 1663 if (mddev->new_level == 6 && 1664 ((mddev->layout == ALGORITHM_PARITY_N && mddev->new_layout == ALGORITHM_PARITY_N) || 1665 __within_range(mddev->new_layout, ALGORITHM_LEFT_ASYMMETRIC_6, ALGORITHM_RIGHT_SYMMETRIC_6))) 1666 return 0; 1667 break; 1668 1669 case 6: 1670 /* raid6 with parity N -> raid0 */ 1671 if (mddev->new_level == 0 && 1672 mddev->layout == ALGORITHM_PARITY_N) 1673 return 0; 1674 1675 /* raid6 with parity N -> raid4 */ 1676 if (mddev->new_level == 4 && 1677 mddev->layout == ALGORITHM_PARITY_N) 1678 return 0; 1679 1680 /* raid6_*_n with Q-Syndrome N -> raid5_* */ 1681 if (mddev->new_level == 5 && 1682 ((mddev->layout == ALGORITHM_PARITY_N && mddev->new_layout == ALGORITHM_PARITY_N) || 1683 __within_range(mddev->new_layout, ALGORITHM_LEFT_ASYMMETRIC, ALGORITHM_RIGHT_SYMMETRIC))) 1684 return 0; 1685 1686 default: 1687 break; 1688 } 1689 1690 rs->ti->error = "takeover not possible"; 1691 return -EINVAL; 1692 } 1693 1694 /* True if @rs requested to be taken over */ 1695 static bool rs_takeover_requested(struct raid_set *rs) 1696 { 1697 return rs->md.new_level != rs->md.level; 1698 } 1699 1700 /* True if @rs is requested to reshape by ctr */ 1701 static bool rs_reshape_requested(struct raid_set *rs) 1702 { 1703 bool change; 1704 struct mddev *mddev = &rs->md; 1705 1706 if (rs_takeover_requested(rs)) 1707 return false; 1708 1709 if (!mddev->level) 1710 return false; 1711 1712 change = mddev->new_layout != mddev->layout || 1713 mddev->new_chunk_sectors != mddev->chunk_sectors || 1714 rs->delta_disks; 1715 1716 /* Historical case to support raid1 reshape without delta disks */ 1717 if (mddev->level == 1) { 1718 if (rs->delta_disks) 1719 return !!rs->delta_disks; 1720 1721 return !change && 1722 mddev->raid_disks != rs->raid_disks; 1723 } 1724 1725 if (mddev->level == 10) 1726 return change && 1727 !__is_raid10_far(mddev->new_layout) && 1728 rs->delta_disks >= 0; 1729 1730 return change; 1731 } 1732 1733 /* Features */ 1734 #define FEATURE_FLAG_SUPPORTS_V190 0x1 /* Supports extended superblock */ 1735 1736 /* State flags for sb->flags */ 1737 #define SB_FLAG_RESHAPE_ACTIVE 0x1 1738 #define SB_FLAG_RESHAPE_BACKWARDS 0x2 1739 1740 /* 1741 * This structure is never routinely used by userspace, unlike md superblocks. 1742 * Devices with this superblock should only ever be accessed via device-mapper. 1743 */ 1744 #define DM_RAID_MAGIC 0x64526D44 1745 struct dm_raid_superblock { 1746 __le32 magic; /* "DmRd" */ 1747 __le32 compat_features; /* Used to indicate compatible features (like 1.9.0 ondisk metadata extension) */ 1748 1749 __le32 num_devices; /* Number of devices in this raid set. (Max 64) */ 1750 __le32 array_position; /* The position of this drive in the raid set */ 1751 1752 __le64 events; /* Incremented by md when superblock updated */ 1753 __le64 failed_devices; /* Pre 1.9.0 part of bit field of devices to */ 1754 /* indicate failures (see extension below) */ 1755 1756 /* 1757 * This offset tracks the progress of the repair or replacement of 1758 * an individual drive. 1759 */ 1760 __le64 disk_recovery_offset; 1761 1762 /* 1763 * This offset tracks the progress of the initial raid set 1764 * synchronisation/parity calculation. 1765 */ 1766 __le64 array_resync_offset; 1767 1768 /* 1769 * raid characteristics 1770 */ 1771 __le32 level; 1772 __le32 layout; 1773 __le32 stripe_sectors; 1774 1775 /******************************************************************** 1776 * BELOW FOLLOW V1.9.0 EXTENSIONS TO THE PRISTINE SUPERBLOCK FORMAT!!! 1777 * 1778 * FEATURE_FLAG_SUPPORTS_V190 in the features member indicates that those exist 1779 */ 1780 1781 __le32 flags; /* Flags defining array states for reshaping */ 1782 1783 /* 1784 * This offset tracks the progress of a raid 1785 * set reshape in order to be able to restart it 1786 */ 1787 __le64 reshape_position; 1788 1789 /* 1790 * These define the properties of the array in case of an interrupted reshape 1791 */ 1792 __le32 new_level; 1793 __le32 new_layout; 1794 __le32 new_stripe_sectors; 1795 __le32 delta_disks; 1796 1797 __le64 array_sectors; /* Array size in sectors */ 1798 1799 /* 1800 * Sector offsets to data on devices (reshaping). 1801 * Needed to support out of place reshaping, thus 1802 * not writing over any stripes whilst converting 1803 * them from old to new layout 1804 */ 1805 __le64 data_offset; 1806 __le64 new_data_offset; 1807 1808 __le64 sectors; /* Used device size in sectors */ 1809 1810 /* 1811 * Additonal Bit field of devices indicating failures to support 1812 * up to 256 devices with the 1.9.0 on-disk metadata format 1813 */ 1814 __le64 extended_failed_devices[DISKS_ARRAY_ELEMS - 1]; 1815 1816 __le32 incompat_features; /* Used to indicate any incompatible features */ 1817 1818 /* Always set rest up to logical block size to 0 when writing (see get_metadata_device() below). */ 1819 } __packed; 1820 1821 /* 1822 * Check for reshape constraints on raid set @rs: 1823 * 1824 * - reshape function non-existent 1825 * - degraded set 1826 * - ongoing recovery 1827 * - ongoing reshape 1828 * 1829 * Returns 0 if none or -EPERM if given constraint 1830 * and error message reference in @errmsg 1831 */ 1832 static int rs_check_reshape(struct raid_set *rs) 1833 { 1834 struct mddev *mddev = &rs->md; 1835 1836 if (!mddev->pers || !mddev->pers->check_reshape) 1837 rs->ti->error = "Reshape not supported"; 1838 else if (mddev->degraded) 1839 rs->ti->error = "Can't reshape degraded raid set"; 1840 else if (rs_is_recovering(rs)) 1841 rs->ti->error = "Convert request on recovering raid set prohibited"; 1842 else if (rs_is_reshaping(rs)) 1843 rs->ti->error = "raid set already reshaping!"; 1844 else if (!(rs_is_raid1(rs) || rs_is_raid10(rs) || rs_is_raid456(rs))) 1845 rs->ti->error = "Reshaping only supported for raid1/4/5/6/10"; 1846 else 1847 return 0; 1848 1849 return -EPERM; 1850 } 1851 1852 static int read_disk_sb(struct md_rdev *rdev, int size) 1853 { 1854 BUG_ON(!rdev->sb_page); 1855 1856 if (rdev->sb_loaded) 1857 return 0; 1858 1859 if (!sync_page_io(rdev, 0, size, rdev->sb_page, REQ_OP_READ, 0, true)) { 1860 DMERR("Failed to read superblock of device at position %d", 1861 rdev->raid_disk); 1862 md_error(rdev->mddev, rdev); 1863 return -EINVAL; 1864 } 1865 1866 rdev->sb_loaded = 1; 1867 1868 return 0; 1869 } 1870 1871 static void sb_retrieve_failed_devices(struct dm_raid_superblock *sb, uint64_t *failed_devices) 1872 { 1873 failed_devices[0] = le64_to_cpu(sb->failed_devices); 1874 memset(failed_devices + 1, 0, sizeof(sb->extended_failed_devices)); 1875 1876 if (le32_to_cpu(sb->compat_features) & FEATURE_FLAG_SUPPORTS_V190) { 1877 int i = ARRAY_SIZE(sb->extended_failed_devices); 1878 1879 while (i--) 1880 failed_devices[i+1] = le64_to_cpu(sb->extended_failed_devices[i]); 1881 } 1882 } 1883 1884 static void sb_update_failed_devices(struct dm_raid_superblock *sb, uint64_t *failed_devices) 1885 { 1886 int i = ARRAY_SIZE(sb->extended_failed_devices); 1887 1888 sb->failed_devices = cpu_to_le64(failed_devices[0]); 1889 while (i--) 1890 sb->extended_failed_devices[i] = cpu_to_le64(failed_devices[i+1]); 1891 } 1892 1893 /* 1894 * Synchronize the superblock members with the raid set properties 1895 * 1896 * All superblock data is little endian. 1897 */ 1898 static void super_sync(struct mddev *mddev, struct md_rdev *rdev) 1899 { 1900 bool update_failed_devices = false; 1901 unsigned int i; 1902 uint64_t failed_devices[DISKS_ARRAY_ELEMS]; 1903 struct dm_raid_superblock *sb; 1904 struct raid_set *rs = container_of(mddev, struct raid_set, md); 1905 1906 /* No metadata device, no superblock */ 1907 if (!rdev->meta_bdev) 1908 return; 1909 1910 BUG_ON(!rdev->sb_page); 1911 1912 sb = page_address(rdev->sb_page); 1913 1914 sb_retrieve_failed_devices(sb, failed_devices); 1915 1916 for (i = 0; i < rs->raid_disks; i++) 1917 if (!rs->dev[i].data_dev || test_bit(Faulty, &rs->dev[i].rdev.flags)) { 1918 update_failed_devices = true; 1919 set_bit(i, (void *) failed_devices); 1920 } 1921 1922 if (update_failed_devices) 1923 sb_update_failed_devices(sb, failed_devices); 1924 1925 sb->magic = cpu_to_le32(DM_RAID_MAGIC); 1926 sb->compat_features = cpu_to_le32(FEATURE_FLAG_SUPPORTS_V190); 1927 1928 sb->num_devices = cpu_to_le32(mddev->raid_disks); 1929 sb->array_position = cpu_to_le32(rdev->raid_disk); 1930 1931 sb->events = cpu_to_le64(mddev->events); 1932 1933 sb->disk_recovery_offset = cpu_to_le64(rdev->recovery_offset); 1934 sb->array_resync_offset = cpu_to_le64(mddev->recovery_cp); 1935 1936 sb->level = cpu_to_le32(mddev->level); 1937 sb->layout = cpu_to_le32(mddev->layout); 1938 sb->stripe_sectors = cpu_to_le32(mddev->chunk_sectors); 1939 1940 sb->new_level = cpu_to_le32(mddev->new_level); 1941 sb->new_layout = cpu_to_le32(mddev->new_layout); 1942 sb->new_stripe_sectors = cpu_to_le32(mddev->new_chunk_sectors); 1943 1944 sb->delta_disks = cpu_to_le32(mddev->delta_disks); 1945 1946 smp_rmb(); /* Make sure we access most recent reshape position */ 1947 sb->reshape_position = cpu_to_le64(mddev->reshape_position); 1948 if (le64_to_cpu(sb->reshape_position) != MaxSector) { 1949 /* Flag ongoing reshape */ 1950 sb->flags |= cpu_to_le32(SB_FLAG_RESHAPE_ACTIVE); 1951 1952 if (mddev->delta_disks < 0 || mddev->reshape_backwards) 1953 sb->flags |= cpu_to_le32(SB_FLAG_RESHAPE_BACKWARDS); 1954 } else { 1955 /* Clear reshape flags */ 1956 sb->flags &= ~(cpu_to_le32(SB_FLAG_RESHAPE_ACTIVE|SB_FLAG_RESHAPE_BACKWARDS)); 1957 } 1958 1959 sb->array_sectors = cpu_to_le64(mddev->array_sectors); 1960 sb->data_offset = cpu_to_le64(rdev->data_offset); 1961 sb->new_data_offset = cpu_to_le64(rdev->new_data_offset); 1962 sb->sectors = cpu_to_le64(rdev->sectors); 1963 sb->incompat_features = cpu_to_le32(0); 1964 1965 /* Zero out the rest of the payload after the size of the superblock */ 1966 memset(sb + 1, 0, rdev->sb_size - sizeof(*sb)); 1967 } 1968 1969 /* 1970 * super_load 1971 * 1972 * This function creates a superblock if one is not found on the device 1973 * and will decide which superblock to use if there's a choice. 1974 * 1975 * Return: 1 if use rdev, 0 if use refdev, -Exxx otherwise 1976 */ 1977 static int super_load(struct md_rdev *rdev, struct md_rdev *refdev) 1978 { 1979 int r; 1980 struct dm_raid_superblock *sb; 1981 struct dm_raid_superblock *refsb; 1982 uint64_t events_sb, events_refsb; 1983 1984 rdev->sb_start = 0; 1985 rdev->sb_size = bdev_logical_block_size(rdev->meta_bdev); 1986 if (rdev->sb_size < sizeof(*sb) || rdev->sb_size > PAGE_SIZE) { 1987 DMERR("superblock size of a logical block is no longer valid"); 1988 return -EINVAL; 1989 } 1990 1991 r = read_disk_sb(rdev, rdev->sb_size); 1992 if (r) 1993 return r; 1994 1995 sb = page_address(rdev->sb_page); 1996 1997 /* 1998 * Two cases that we want to write new superblocks and rebuild: 1999 * 1) New device (no matching magic number) 2000 * 2) Device specified for rebuild (!In_sync w/ offset == 0) 2001 */ 2002 if ((sb->magic != cpu_to_le32(DM_RAID_MAGIC)) || 2003 (!test_bit(In_sync, &rdev->flags) && !rdev->recovery_offset)) { 2004 super_sync(rdev->mddev, rdev); 2005 2006 set_bit(FirstUse, &rdev->flags); 2007 sb->compat_features = cpu_to_le32(FEATURE_FLAG_SUPPORTS_V190); 2008 2009 /* Force writing of superblocks to disk */ 2010 set_bit(MD_CHANGE_DEVS, &rdev->mddev->flags); 2011 2012 /* Any superblock is better than none, choose that if given */ 2013 return refdev ? 0 : 1; 2014 } 2015 2016 if (!refdev) 2017 return 1; 2018 2019 events_sb = le64_to_cpu(sb->events); 2020 2021 refsb = page_address(refdev->sb_page); 2022 events_refsb = le64_to_cpu(refsb->events); 2023 2024 return (events_sb > events_refsb) ? 1 : 0; 2025 } 2026 2027 static int super_init_validation(struct raid_set *rs, struct md_rdev *rdev) 2028 { 2029 int role; 2030 unsigned int d; 2031 struct mddev *mddev = &rs->md; 2032 uint64_t events_sb; 2033 uint64_t failed_devices[DISKS_ARRAY_ELEMS]; 2034 struct dm_raid_superblock *sb; 2035 uint32_t new_devs = 0, rebuild_and_new = 0, rebuilds = 0; 2036 struct md_rdev *r; 2037 struct dm_raid_superblock *sb2; 2038 2039 sb = page_address(rdev->sb_page); 2040 events_sb = le64_to_cpu(sb->events); 2041 2042 /* 2043 * Initialise to 1 if this is a new superblock. 2044 */ 2045 mddev->events = events_sb ? : 1; 2046 2047 mddev->reshape_position = MaxSector; 2048 2049 /* 2050 * Reshaping is supported, e.g. reshape_position is valid 2051 * in superblock and superblock content is authoritative. 2052 */ 2053 if (le32_to_cpu(sb->compat_features) & FEATURE_FLAG_SUPPORTS_V190) { 2054 /* Superblock is authoritative wrt given raid set layout! */ 2055 mddev->raid_disks = le32_to_cpu(sb->num_devices); 2056 mddev->level = le32_to_cpu(sb->level); 2057 mddev->layout = le32_to_cpu(sb->layout); 2058 mddev->chunk_sectors = le32_to_cpu(sb->stripe_sectors); 2059 mddev->new_level = le32_to_cpu(sb->new_level); 2060 mddev->new_layout = le32_to_cpu(sb->new_layout); 2061 mddev->new_chunk_sectors = le32_to_cpu(sb->new_stripe_sectors); 2062 mddev->delta_disks = le32_to_cpu(sb->delta_disks); 2063 mddev->array_sectors = le64_to_cpu(sb->array_sectors); 2064 2065 /* raid was reshaping and got interrupted */ 2066 if (le32_to_cpu(sb->flags) & SB_FLAG_RESHAPE_ACTIVE) { 2067 if (test_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags)) { 2068 DMERR("Reshape requested but raid set is still reshaping"); 2069 return -EINVAL; 2070 } 2071 2072 if (mddev->delta_disks < 0 || 2073 (!mddev->delta_disks && (le32_to_cpu(sb->flags) & SB_FLAG_RESHAPE_BACKWARDS))) 2074 mddev->reshape_backwards = 1; 2075 else 2076 mddev->reshape_backwards = 0; 2077 2078 mddev->reshape_position = le64_to_cpu(sb->reshape_position); 2079 rs->raid_type = get_raid_type_by_ll(mddev->level, mddev->layout); 2080 } 2081 2082 } else { 2083 /* 2084 * No takeover/reshaping, because we don't have the extended v1.9.0 metadata 2085 */ 2086 if (le32_to_cpu(sb->level) != mddev->level) { 2087 DMERR("Reshaping/takeover raid sets not yet supported. (raid level/stripes/size change)"); 2088 return -EINVAL; 2089 } 2090 if (le32_to_cpu(sb->layout) != mddev->layout) { 2091 DMERR("Reshaping raid sets not yet supported. (raid layout change)"); 2092 DMERR(" 0x%X vs 0x%X", le32_to_cpu(sb->layout), mddev->layout); 2093 DMERR(" Old layout: %s w/ %d copies", 2094 raid10_md_layout_to_format(le32_to_cpu(sb->layout)), 2095 raid10_md_layout_to_copies(le32_to_cpu(sb->layout))); 2096 DMERR(" New layout: %s w/ %d copies", 2097 raid10_md_layout_to_format(mddev->layout), 2098 raid10_md_layout_to_copies(mddev->layout)); 2099 return -EINVAL; 2100 } 2101 if (le32_to_cpu(sb->stripe_sectors) != mddev->chunk_sectors) { 2102 DMERR("Reshaping raid sets not yet supported. (stripe sectors change)"); 2103 return -EINVAL; 2104 } 2105 2106 /* We can only change the number of devices in raid1 with old (i.e. pre 1.0.7) metadata */ 2107 if (!rt_is_raid1(rs->raid_type) && 2108 (le32_to_cpu(sb->num_devices) != mddev->raid_disks)) { 2109 DMERR("Reshaping raid sets not yet supported. (device count change from %u to %u)", 2110 sb->num_devices, mddev->raid_disks); 2111 return -EINVAL; 2112 } 2113 2114 /* Table line is checked vs. authoritative superblock */ 2115 rs_set_new(rs); 2116 } 2117 2118 if (!test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) 2119 mddev->recovery_cp = le64_to_cpu(sb->array_resync_offset); 2120 2121 /* 2122 * During load, we set FirstUse if a new superblock was written. 2123 * There are two reasons we might not have a superblock: 2124 * 1) The raid set is brand new - in which case, all of the 2125 * devices must have their In_sync bit set. Also, 2126 * recovery_cp must be 0, unless forced. 2127 * 2) This is a new device being added to an old raid set 2128 * and the new device needs to be rebuilt - in which 2129 * case the In_sync bit will /not/ be set and 2130 * recovery_cp must be MaxSector. 2131 * 3) This is/are a new device(s) being added to an old 2132 * raid set during takeover to a higher raid level 2133 * to provide capacity for redundancy or during reshape 2134 * to add capacity to grow the raid set. 2135 */ 2136 d = 0; 2137 rdev_for_each(r, mddev) { 2138 if (test_bit(FirstUse, &r->flags)) 2139 new_devs++; 2140 2141 if (!test_bit(In_sync, &r->flags)) { 2142 DMINFO("Device %d specified for rebuild; clearing superblock", 2143 r->raid_disk); 2144 rebuilds++; 2145 2146 if (test_bit(FirstUse, &r->flags)) 2147 rebuild_and_new++; 2148 } 2149 2150 d++; 2151 } 2152 2153 if (new_devs == rs->raid_disks || !rebuilds) { 2154 /* Replace a broken device */ 2155 if (new_devs == 1 && !rs->delta_disks) 2156 ; 2157 if (new_devs == rs->raid_disks) { 2158 DMINFO("Superblocks created for new raid set"); 2159 set_bit(MD_ARRAY_FIRST_USE, &mddev->flags); 2160 } else if (new_devs != rebuilds && 2161 new_devs != rs->delta_disks) { 2162 DMERR("New device injected into existing raid set without " 2163 "'delta_disks' or 'rebuild' parameter specified"); 2164 return -EINVAL; 2165 } 2166 } else if (new_devs && new_devs != rebuilds) { 2167 DMERR("%u 'rebuild' devices cannot be injected into" 2168 " a raid set with %u other first-time devices", 2169 rebuilds, new_devs); 2170 return -EINVAL; 2171 } else if (rebuilds) { 2172 if (rebuild_and_new && rebuilds != rebuild_and_new) { 2173 DMERR("new device%s provided without 'rebuild'", 2174 new_devs > 1 ? "s" : ""); 2175 return -EINVAL; 2176 } else if (rs_is_recovering(rs)) { 2177 DMERR("'rebuild' specified while raid set is not in-sync (recovery_cp=%llu)", 2178 (unsigned long long) mddev->recovery_cp); 2179 return -EINVAL; 2180 } else if (rs_is_reshaping(rs)) { 2181 DMERR("'rebuild' specified while raid set is being reshaped (reshape_position=%llu)", 2182 (unsigned long long) mddev->reshape_position); 2183 return -EINVAL; 2184 } 2185 } 2186 2187 /* 2188 * Now we set the Faulty bit for those devices that are 2189 * recorded in the superblock as failed. 2190 */ 2191 sb_retrieve_failed_devices(sb, failed_devices); 2192 rdev_for_each(r, mddev) { 2193 if (!r->sb_page) 2194 continue; 2195 sb2 = page_address(r->sb_page); 2196 sb2->failed_devices = 0; 2197 memset(sb2->extended_failed_devices, 0, sizeof(sb2->extended_failed_devices)); 2198 2199 /* 2200 * Check for any device re-ordering. 2201 */ 2202 if (!test_bit(FirstUse, &r->flags) && (r->raid_disk >= 0)) { 2203 role = le32_to_cpu(sb2->array_position); 2204 if (role < 0) 2205 continue; 2206 2207 if (role != r->raid_disk) { 2208 if (__is_raid10_near(mddev->layout)) { 2209 if (mddev->raid_disks % __raid10_near_copies(mddev->layout) || 2210 rs->raid_disks % rs->raid10_copies) { 2211 rs->ti->error = 2212 "Cannot change raid10 near set to odd # of devices!"; 2213 return -EINVAL; 2214 } 2215 2216 sb2->array_position = cpu_to_le32(r->raid_disk); 2217 2218 } else if (!(rs_is_raid10(rs) && rt_is_raid0(rs->raid_type)) && 2219 !(rs_is_raid0(rs) && rt_is_raid10(rs->raid_type)) && 2220 !rt_is_raid1(rs->raid_type)) { 2221 rs->ti->error = "Cannot change device positions in raid set"; 2222 return -EINVAL; 2223 } 2224 2225 DMINFO("raid device #%d now at position #%d", role, r->raid_disk); 2226 } 2227 2228 /* 2229 * Partial recovery is performed on 2230 * returning failed devices. 2231 */ 2232 if (test_bit(role, (void *) failed_devices)) 2233 set_bit(Faulty, &r->flags); 2234 } 2235 } 2236 2237 return 0; 2238 } 2239 2240 static int super_validate(struct raid_set *rs, struct md_rdev *rdev) 2241 { 2242 struct mddev *mddev = &rs->md; 2243 struct dm_raid_superblock *sb; 2244 2245 if (rs_is_raid0(rs) || !rdev->sb_page) 2246 return 0; 2247 2248 sb = page_address(rdev->sb_page); 2249 2250 /* 2251 * If mddev->events is not set, we know we have not yet initialized 2252 * the array. 2253 */ 2254 if (!mddev->events && super_init_validation(rs, rdev)) 2255 return -EINVAL; 2256 2257 if (le32_to_cpu(sb->compat_features) != FEATURE_FLAG_SUPPORTS_V190) { 2258 rs->ti->error = "Unable to assemble array: Unknown flag(s) in compatible feature flags"; 2259 return -EINVAL; 2260 } 2261 2262 if (sb->incompat_features) { 2263 rs->ti->error = "Unable to assemble array: No incompatible feature flags supported yet"; 2264 return -EINVAL; 2265 } 2266 2267 /* Enable bitmap creation for RAID levels != 0 */ 2268 mddev->bitmap_info.offset = rt_is_raid0(rs->raid_type) ? 0 : to_sector(4096); 2269 rdev->mddev->bitmap_info.default_offset = mddev->bitmap_info.offset; 2270 2271 if (!test_and_clear_bit(FirstUse, &rdev->flags)) { 2272 /* Retrieve device size stored in superblock to be prepared for shrink */ 2273 rdev->sectors = le64_to_cpu(sb->sectors); 2274 rdev->recovery_offset = le64_to_cpu(sb->disk_recovery_offset); 2275 if (rdev->recovery_offset == MaxSector) 2276 set_bit(In_sync, &rdev->flags); 2277 /* 2278 * If no reshape in progress -> we're recovering single 2279 * disk(s) and have to set the device(s) to out-of-sync 2280 */ 2281 else if (!rs_is_reshaping(rs)) 2282 clear_bit(In_sync, &rdev->flags); /* Mandatory for recovery */ 2283 } 2284 2285 /* 2286 * If a device comes back, set it as not In_sync and no longer faulty. 2287 */ 2288 if (test_and_clear_bit(Faulty, &rdev->flags)) { 2289 rdev->recovery_offset = 0; 2290 clear_bit(In_sync, &rdev->flags); 2291 rdev->saved_raid_disk = rdev->raid_disk; 2292 } 2293 2294 /* Reshape support -> restore repective data offsets */ 2295 rdev->data_offset = le64_to_cpu(sb->data_offset); 2296 rdev->new_data_offset = le64_to_cpu(sb->new_data_offset); 2297 2298 return 0; 2299 } 2300 2301 /* 2302 * Analyse superblocks and select the freshest. 2303 */ 2304 static int analyse_superblocks(struct dm_target *ti, struct raid_set *rs) 2305 { 2306 int r; 2307 struct raid_dev *dev; 2308 struct md_rdev *rdev, *tmp, *freshest; 2309 struct mddev *mddev = &rs->md; 2310 2311 freshest = NULL; 2312 rdev_for_each_safe(rdev, tmp, mddev) { 2313 /* 2314 * Skipping super_load due to CTR_FLAG_SYNC will cause 2315 * the array to undergo initialization again as 2316 * though it were new. This is the intended effect 2317 * of the "sync" directive. 2318 * 2319 * When reshaping capability is added, we must ensure 2320 * that the "sync" directive is disallowed during the 2321 * reshape. 2322 */ 2323 if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags)) 2324 continue; 2325 2326 if (!rdev->meta_bdev) 2327 continue; 2328 2329 r = super_load(rdev, freshest); 2330 2331 switch (r) { 2332 case 1: 2333 freshest = rdev; 2334 break; 2335 case 0: 2336 break; 2337 default: 2338 dev = container_of(rdev, struct raid_dev, rdev); 2339 if (dev->meta_dev) 2340 dm_put_device(ti, dev->meta_dev); 2341 2342 dev->meta_dev = NULL; 2343 rdev->meta_bdev = NULL; 2344 2345 if (rdev->sb_page) 2346 put_page(rdev->sb_page); 2347 2348 rdev->sb_page = NULL; 2349 2350 rdev->sb_loaded = 0; 2351 2352 /* 2353 * We might be able to salvage the data device 2354 * even though the meta device has failed. For 2355 * now, we behave as though '- -' had been 2356 * set for this device in the table. 2357 */ 2358 if (dev->data_dev) 2359 dm_put_device(ti, dev->data_dev); 2360 2361 dev->data_dev = NULL; 2362 rdev->bdev = NULL; 2363 2364 list_del(&rdev->same_set); 2365 } 2366 } 2367 2368 if (!freshest) 2369 return 0; 2370 2371 if (validate_raid_redundancy(rs)) { 2372 rs->ti->error = "Insufficient redundancy to activate array"; 2373 return -EINVAL; 2374 } 2375 2376 /* 2377 * Validation of the freshest device provides the source of 2378 * validation for the remaining devices. 2379 */ 2380 rs->ti->error = "Unable to assemble array: Invalid superblocks"; 2381 if (super_validate(rs, freshest)) 2382 return -EINVAL; 2383 2384 rdev_for_each(rdev, mddev) 2385 if ((rdev != freshest) && super_validate(rs, rdev)) 2386 return -EINVAL; 2387 return 0; 2388 } 2389 2390 /* 2391 * Adjust data_offset and new_data_offset on all disk members of @rs 2392 * for out of place reshaping if requested by contructor 2393 * 2394 * We need free space at the beginning of each raid disk for forward 2395 * and at the end for backward reshapes which userspace has to provide 2396 * via remapping/reordering of space. 2397 */ 2398 static int rs_adjust_data_offsets(struct raid_set *rs) 2399 { 2400 sector_t data_offset = 0, new_data_offset = 0; 2401 struct md_rdev *rdev; 2402 2403 /* Constructor did not request data offset change */ 2404 if (!test_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags)) { 2405 if (!rs_is_reshapable(rs)) 2406 goto out; 2407 2408 return 0; 2409 } 2410 2411 /* HM FIXME: get InSync raid_dev? */ 2412 rdev = &rs->dev[0].rdev; 2413 2414 if (rs->delta_disks < 0) { 2415 /* 2416 * Removing disks (reshaping backwards): 2417 * 2418 * - before reshape: data is at offset 0 and free space 2419 * is at end of each component LV 2420 * 2421 * - after reshape: data is at offset rs->data_offset != 0 on each component LV 2422 */ 2423 data_offset = 0; 2424 new_data_offset = rs->data_offset; 2425 2426 } else if (rs->delta_disks > 0) { 2427 /* 2428 * Adding disks (reshaping forwards): 2429 * 2430 * - before reshape: data is at offset rs->data_offset != 0 and 2431 * free space is at begin of each component LV 2432 * 2433 * - after reshape: data is at offset 0 on each component LV 2434 */ 2435 data_offset = rs->data_offset; 2436 new_data_offset = 0; 2437 2438 } else { 2439 /* 2440 * User space passes in 0 for data offset after having removed reshape space 2441 * 2442 * - or - (data offset != 0) 2443 * 2444 * Changing RAID layout or chunk size -> toggle offsets 2445 * 2446 * - before reshape: data is at offset rs->data_offset 0 and 2447 * free space is at end of each component LV 2448 * -or- 2449 * data is at offset rs->data_offset != 0 and 2450 * free space is at begin of each component LV 2451 * 2452 * - after reshape: data is at offset 0 if it was at offset != 0 2453 * or at offset != 0 if it was at offset 0 2454 * on each component LV 2455 * 2456 */ 2457 data_offset = rs->data_offset ? rdev->data_offset : 0; 2458 new_data_offset = data_offset ? 0 : rs->data_offset; 2459 set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags); 2460 } 2461 2462 /* 2463 * Make sure we got a minimum amount of free sectors per device 2464 */ 2465 if (rs->data_offset && 2466 to_sector(i_size_read(rdev->bdev->bd_inode)) - rdev->sectors < MIN_FREE_RESHAPE_SPACE) { 2467 rs->ti->error = data_offset ? "No space for forward reshape" : 2468 "No space for backward reshape"; 2469 return -ENOSPC; 2470 } 2471 out: 2472 /* Adjust data offsets on all rdevs */ 2473 rdev_for_each(rdev, &rs->md) { 2474 rdev->data_offset = data_offset; 2475 rdev->new_data_offset = new_data_offset; 2476 } 2477 2478 return 0; 2479 } 2480 2481 /* Userpace reordered disks -> adjust raid_disk indexes in @rs */ 2482 static void __reorder_raid_disk_indexes(struct raid_set *rs) 2483 { 2484 int i = 0; 2485 struct md_rdev *rdev; 2486 2487 rdev_for_each(rdev, &rs->md) { 2488 rdev->raid_disk = i++; 2489 rdev->saved_raid_disk = rdev->new_raid_disk = -1; 2490 } 2491 } 2492 2493 /* 2494 * Setup @rs for takeover by a different raid level 2495 */ 2496 static int rs_setup_takeover(struct raid_set *rs) 2497 { 2498 struct mddev *mddev = &rs->md; 2499 struct md_rdev *rdev; 2500 unsigned int d = mddev->raid_disks = rs->raid_disks; 2501 sector_t new_data_offset = rs->dev[0].rdev.data_offset ? 0 : rs->data_offset; 2502 2503 if (rt_is_raid10(rs->raid_type)) { 2504 if (mddev->level == 0) { 2505 /* Userpace reordered disks -> adjust raid_disk indexes */ 2506 __reorder_raid_disk_indexes(rs); 2507 2508 /* raid0 -> raid10_far layout */ 2509 mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_FAR, 2510 rs->raid10_copies); 2511 } else if (mddev->level == 1) 2512 /* raid1 -> raid10_near layout */ 2513 mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_NEAR, 2514 rs->raid_disks); 2515 else 2516 return -EINVAL; 2517 2518 } 2519 2520 clear_bit(MD_ARRAY_FIRST_USE, &mddev->flags); 2521 mddev->recovery_cp = MaxSector; 2522 2523 while (d--) { 2524 rdev = &rs->dev[d].rdev; 2525 2526 if (test_bit(d, (void *) rs->rebuild_disks)) { 2527 clear_bit(In_sync, &rdev->flags); 2528 clear_bit(Faulty, &rdev->flags); 2529 mddev->recovery_cp = rdev->recovery_offset = 0; 2530 /* Bitmap has to be created when we do an "up" takeover */ 2531 set_bit(MD_ARRAY_FIRST_USE, &mddev->flags); 2532 } 2533 2534 rdev->new_data_offset = new_data_offset; 2535 } 2536 2537 return 0; 2538 } 2539 2540 /* Prepare @rs for reshape */ 2541 static int rs_prepare_reshape(struct raid_set *rs) 2542 { 2543 bool reshape; 2544 struct mddev *mddev = &rs->md; 2545 2546 if (rs_is_raid10(rs)) { 2547 if (rs->raid_disks != mddev->raid_disks && 2548 __is_raid10_near(mddev->layout) && 2549 rs->raid10_copies && 2550 rs->raid10_copies != __raid10_near_copies(mddev->layout)) { 2551 /* 2552 * raid disk have to be multiple of data copies to allow this conversion, 2553 * 2554 * This is actually not a reshape it is a 2555 * rebuild of any additional mirrors per group 2556 */ 2557 if (rs->raid_disks % rs->raid10_copies) { 2558 rs->ti->error = "Can't reshape raid10 mirror groups"; 2559 return -EINVAL; 2560 } 2561 2562 /* Userpace reordered disks to add/remove mirrors -> adjust raid_disk indexes */ 2563 __reorder_raid_disk_indexes(rs); 2564 mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_NEAR, 2565 rs->raid10_copies); 2566 mddev->new_layout = mddev->layout; 2567 reshape = false; 2568 } else 2569 reshape = true; 2570 2571 } else if (rs_is_raid456(rs)) 2572 reshape = true; 2573 2574 else if (rs_is_raid1(rs)) { 2575 if (rs->delta_disks) { 2576 /* Process raid1 via delta_disks */ 2577 mddev->degraded = rs->delta_disks < 0 ? -rs->delta_disks : rs->delta_disks; 2578 reshape = true; 2579 } else { 2580 /* Process raid1 without delta_disks */ 2581 mddev->raid_disks = rs->raid_disks; 2582 set_bit(RT_FLAG_KEEP_RS_FROZEN, &rs->runtime_flags); 2583 reshape = false; 2584 } 2585 } else { 2586 rs->ti->error = "Called with bogus raid type"; 2587 return -EINVAL; 2588 } 2589 2590 if (reshape) { 2591 set_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags); 2592 set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags); 2593 set_bit(RT_FLAG_KEEP_RS_FROZEN, &rs->runtime_flags); 2594 } else if (mddev->raid_disks < rs->raid_disks) 2595 /* Create new superblocks and bitmaps, if any new disks */ 2596 set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags); 2597 2598 return 0; 2599 } 2600 2601 /* 2602 * 2603 * - change raid layout 2604 * - change chunk size 2605 * - add disks 2606 * - remove disks 2607 */ 2608 static int rs_setup_reshape(struct raid_set *rs) 2609 { 2610 int r = 0; 2611 unsigned int cur_raid_devs, d; 2612 struct mddev *mddev = &rs->md; 2613 struct md_rdev *rdev; 2614 2615 mddev->delta_disks = rs->delta_disks; 2616 cur_raid_devs = mddev->raid_disks; 2617 2618 /* Ignore impossible layout change whilst adding/removing disks */ 2619 if (mddev->delta_disks && 2620 mddev->layout != mddev->new_layout) { 2621 DMINFO("Ignoring invalid layout change with delta_disks=%d", rs->delta_disks); 2622 mddev->new_layout = mddev->layout; 2623 } 2624 2625 /* 2626 * Adjust array size: 2627 * 2628 * - in case of adding disks, array size has 2629 * to grow after the disk adding reshape, 2630 * which'll hapen in the event handler; 2631 * reshape will happen forward, so space has to 2632 * be available at the beginning of each disk 2633 * 2634 * - in case of removing disks, array size 2635 * has to shrink before starting the reshape, 2636 * which'll happen here; 2637 * reshape will happen backward, so space has to 2638 * be available at the end of each disk 2639 * 2640 * - data_offset and new_data_offset are 2641 * adjusted for aforementioned out of place 2642 * reshaping based on userspace passing in 2643 * the "data_offset <sectors>" key/value 2644 * pair via the constructor 2645 */ 2646 2647 /* Add disk(s) */ 2648 if (rs->delta_disks > 0) { 2649 /* Prepare disks for check in raid4/5/6/10 {check|start}_reshape */ 2650 for (d = cur_raid_devs; d < rs->raid_disks; d++) { 2651 rdev = &rs->dev[d].rdev; 2652 clear_bit(In_sync, &rdev->flags); 2653 2654 /* 2655 * save_raid_disk needs to be -1, or recovery_offset will be set to 0 2656 * by md, which'll store that erroneously in the superblock on reshape 2657 */ 2658 rdev->saved_raid_disk = -1; 2659 rdev->raid_disk = d; 2660 2661 rdev->sectors = mddev->dev_sectors; 2662 rdev->recovery_offset = rs_is_raid1(rs) ? 0 : MaxSector; 2663 } 2664 2665 mddev->reshape_backwards = 0; /* adding disks -> forward reshape */ 2666 2667 /* Remove disk(s) */ 2668 } else if (rs->delta_disks < 0) { 2669 r = rs_set_dev_and_array_sectors(rs, true); 2670 mddev->reshape_backwards = 1; /* removing disk(s) -> backward reshape */ 2671 2672 /* Change layout and/or chunk size */ 2673 } else { 2674 /* 2675 * Reshape layout (e.g. raid5_ls -> raid5_n) and/or chunk size: 2676 * 2677 * keeping number of disks and do layout change -> 2678 * 2679 * toggle reshape_backward depending on data_offset: 2680 * 2681 * - free space upfront -> reshape forward 2682 * 2683 * - free space at the end -> reshape backward 2684 * 2685 * 2686 * This utilizes free reshape space avoiding the need 2687 * for userspace to move (parts of) LV segments in 2688 * case of layout/chunksize change (for disk 2689 * adding/removing reshape space has to be at 2690 * the proper address (see above with delta_disks): 2691 * 2692 * add disk(s) -> begin 2693 * remove disk(s)-> end 2694 */ 2695 mddev->reshape_backwards = rs->dev[0].rdev.data_offset ? 0 : 1; 2696 } 2697 2698 return r; 2699 } 2700 2701 /* 2702 * Enable/disable discard support on RAID set depending on 2703 * RAID level and discard properties of underlying RAID members. 2704 */ 2705 static void configure_discard_support(struct raid_set *rs) 2706 { 2707 int i; 2708 bool raid456; 2709 struct dm_target *ti = rs->ti; 2710 2711 /* Assume discards not supported until after checks below. */ 2712 ti->discards_supported = false; 2713 2714 /* RAID level 4,5,6 require discard_zeroes_data for data integrity! */ 2715 raid456 = (rs->md.level == 4 || rs->md.level == 5 || rs->md.level == 6); 2716 2717 for (i = 0; i < rs->raid_disks; i++) { 2718 struct request_queue *q; 2719 2720 if (!rs->dev[i].rdev.bdev) 2721 continue; 2722 2723 q = bdev_get_queue(rs->dev[i].rdev.bdev); 2724 if (!q || !blk_queue_discard(q)) 2725 return; 2726 2727 if (raid456) { 2728 if (!q->limits.discard_zeroes_data) 2729 return; 2730 if (!devices_handle_discard_safely) { 2731 DMERR("raid456 discard support disabled due to discard_zeroes_data uncertainty."); 2732 DMERR("Set dm-raid.devices_handle_discard_safely=Y to override."); 2733 return; 2734 } 2735 } 2736 } 2737 2738 /* All RAID members properly support discards */ 2739 ti->discards_supported = true; 2740 2741 /* 2742 * RAID1 and RAID10 personalities require bio splitting, 2743 * RAID0/4/5/6 don't and process large discard bios properly. 2744 */ 2745 ti->split_discard_bios = !!(rs->md.level == 1 || rs->md.level == 10); 2746 ti->num_discard_bios = 1; 2747 } 2748 2749 /* 2750 * Construct a RAID0/1/10/4/5/6 mapping: 2751 * Args: 2752 * <raid_type> <#raid_params> <raid_params>{0,} \ 2753 * <#raid_devs> [<meta_dev1> <dev1>]{1,} 2754 * 2755 * <raid_params> varies by <raid_type>. See 'parse_raid_params' for 2756 * details on possible <raid_params>. 2757 * 2758 * Userspace is free to initialize the metadata devices, hence the superblocks to 2759 * enforce recreation based on the passed in table parameters. 2760 * 2761 */ 2762 static int raid_ctr(struct dm_target *ti, unsigned int argc, char **argv) 2763 { 2764 int r; 2765 bool resize; 2766 struct raid_type *rt; 2767 unsigned int num_raid_params, num_raid_devs; 2768 sector_t calculated_dev_sectors; 2769 struct raid_set *rs = NULL; 2770 const char *arg; 2771 struct rs_layout rs_layout; 2772 struct dm_arg_set as = { argc, argv }, as_nrd; 2773 struct dm_arg _args[] = { 2774 { 0, as.argc, "Cannot understand number of raid parameters" }, 2775 { 1, 254, "Cannot understand number of raid devices parameters" } 2776 }; 2777 2778 /* Must have <raid_type> */ 2779 arg = dm_shift_arg(&as); 2780 if (!arg) { 2781 ti->error = "No arguments"; 2782 return -EINVAL; 2783 } 2784 2785 rt = get_raid_type(arg); 2786 if (!rt) { 2787 ti->error = "Unrecognised raid_type"; 2788 return -EINVAL; 2789 } 2790 2791 /* Must have <#raid_params> */ 2792 if (dm_read_arg_group(_args, &as, &num_raid_params, &ti->error)) 2793 return -EINVAL; 2794 2795 /* number of raid device tupples <meta_dev data_dev> */ 2796 as_nrd = as; 2797 dm_consume_args(&as_nrd, num_raid_params); 2798 _args[1].max = (as_nrd.argc - 1) / 2; 2799 if (dm_read_arg(_args + 1, &as_nrd, &num_raid_devs, &ti->error)) 2800 return -EINVAL; 2801 2802 if (!__within_range(num_raid_devs, 1, MAX_RAID_DEVICES)) { 2803 ti->error = "Invalid number of supplied raid devices"; 2804 return -EINVAL; 2805 } 2806 2807 rs = raid_set_alloc(ti, rt, num_raid_devs); 2808 if (IS_ERR(rs)) 2809 return PTR_ERR(rs); 2810 2811 r = parse_raid_params(rs, &as, num_raid_params); 2812 if (r) 2813 goto bad; 2814 2815 r = parse_dev_params(rs, &as); 2816 if (r) 2817 goto bad; 2818 2819 rs->md.sync_super = super_sync; 2820 2821 /* 2822 * Calculate ctr requested array and device sizes to allow 2823 * for superblock analysis needing device sizes defined. 2824 * 2825 * Any existing superblock will overwrite the array and device sizes 2826 */ 2827 r = rs_set_dev_and_array_sectors(rs, false); 2828 if (r) 2829 goto bad; 2830 2831 calculated_dev_sectors = rs->dev[0].rdev.sectors; 2832 2833 /* 2834 * Backup any new raid set level, layout, ... 2835 * requested to be able to compare to superblock 2836 * members for conversion decisions. 2837 */ 2838 rs_config_backup(rs, &rs_layout); 2839 2840 r = analyse_superblocks(ti, rs); 2841 if (r) 2842 goto bad; 2843 2844 resize = calculated_dev_sectors != rs->dev[0].rdev.sectors; 2845 2846 INIT_WORK(&rs->md.event_work, do_table_event); 2847 ti->private = rs; 2848 ti->num_flush_bios = 1; 2849 2850 /* Restore any requested new layout for conversion decision */ 2851 rs_config_restore(rs, &rs_layout); 2852 2853 /* 2854 * Now that we have any superblock metadata available, 2855 * check for new, recovering, reshaping, to be taken over, 2856 * to be reshaped or an existing, unchanged raid set to 2857 * run in sequence. 2858 */ 2859 if (test_bit(MD_ARRAY_FIRST_USE, &rs->md.flags)) { 2860 /* A new raid6 set has to be recovered to ensure proper parity and Q-Syndrome */ 2861 if (rs_is_raid6(rs) && 2862 test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) { 2863 ti->error = "'nosync' not allowed for new raid6 set"; 2864 r = -EINVAL; 2865 goto bad; 2866 } 2867 rs_setup_recovery(rs, 0); 2868 set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags); 2869 rs_set_new(rs); 2870 } else if (rs_is_recovering(rs)) { 2871 /* A recovering raid set may be resized */ 2872 ; /* skip setup rs */ 2873 } else if (rs_is_reshaping(rs)) { 2874 /* Have to reject size change request during reshape */ 2875 if (resize) { 2876 ti->error = "Can't resize a reshaping raid set"; 2877 r = -EPERM; 2878 goto bad; 2879 } 2880 /* skip setup rs */ 2881 } else if (rs_takeover_requested(rs)) { 2882 if (rs_is_reshaping(rs)) { 2883 ti->error = "Can't takeover a reshaping raid set"; 2884 r = -EPERM; 2885 goto bad; 2886 } 2887 2888 /* 2889 * If a takeover is needed, userspace sets any additional 2890 * devices to rebuild and we can check for a valid request here. 2891 * 2892 * If acceptible, set the level to the new requested 2893 * one, prohibit requesting recovery, allow the raid 2894 * set to run and store superblocks during resume. 2895 */ 2896 r = rs_check_takeover(rs); 2897 if (r) 2898 goto bad; 2899 2900 r = rs_setup_takeover(rs); 2901 if (r) 2902 goto bad; 2903 2904 set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags); 2905 set_bit(RT_FLAG_KEEP_RS_FROZEN, &rs->runtime_flags); 2906 /* Takeover ain't recovery, so disable recovery */ 2907 rs_setup_recovery(rs, MaxSector); 2908 rs_set_new(rs); 2909 } else if (rs_reshape_requested(rs)) { 2910 /* 2911 * We can only prepare for a reshape here, because the 2912 * raid set needs to run to provide the repective reshape 2913 * check functions via its MD personality instance. 2914 * 2915 * So do the reshape check after md_run() succeeded. 2916 */ 2917 r = rs_prepare_reshape(rs); 2918 if (r) 2919 return r; 2920 2921 /* Reshaping ain't recovery, so disable recovery */ 2922 rs_setup_recovery(rs, MaxSector); 2923 rs_set_cur(rs); 2924 } else { 2925 /* May not set recovery when a device rebuild is requested */ 2926 if (test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags)) { 2927 rs_setup_recovery(rs, MaxSector); 2928 set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags); 2929 } else 2930 rs_setup_recovery(rs, test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags) ? 2931 0 : (resize ? calculated_dev_sectors : MaxSector)); 2932 rs_set_cur(rs); 2933 } 2934 2935 /* If constructor requested it, change data and new_data offsets */ 2936 r = rs_adjust_data_offsets(rs); 2937 if (r) 2938 goto bad; 2939 2940 /* Start raid set read-only and assumed clean to change in raid_resume() */ 2941 rs->md.ro = 1; 2942 rs->md.in_sync = 1; 2943 set_bit(MD_RECOVERY_FROZEN, &rs->md.recovery); 2944 2945 /* Has to be held on running the array */ 2946 mddev_lock_nointr(&rs->md); 2947 r = md_run(&rs->md); 2948 rs->md.in_sync = 0; /* Assume already marked dirty */ 2949 2950 if (r) { 2951 ti->error = "Failed to run raid array"; 2952 mddev_unlock(&rs->md); 2953 goto bad; 2954 } 2955 2956 rs->callbacks.congested_fn = raid_is_congested; 2957 dm_table_add_target_callbacks(ti->table, &rs->callbacks); 2958 2959 mddev_suspend(&rs->md); 2960 2961 /* Try to adjust the raid4/5/6 stripe cache size to the stripe size */ 2962 if (rs_is_raid456(rs)) { 2963 r = rs_set_raid456_stripe_cache(rs); 2964 if (r) 2965 goto bad_stripe_cache; 2966 } 2967 2968 /* Now do an early reshape check */ 2969 if (test_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags)) { 2970 r = rs_check_reshape(rs); 2971 if (r) 2972 goto bad_check_reshape; 2973 2974 /* Restore new, ctr requested layout to perform check */ 2975 rs_config_restore(rs, &rs_layout); 2976 2977 if (rs->md.pers->start_reshape) { 2978 r = rs->md.pers->check_reshape(&rs->md); 2979 if (r) { 2980 ti->error = "Reshape check failed"; 2981 goto bad_check_reshape; 2982 } 2983 } 2984 } 2985 2986 mddev_unlock(&rs->md); 2987 return 0; 2988 2989 bad_stripe_cache: 2990 bad_check_reshape: 2991 md_stop(&rs->md); 2992 bad: 2993 raid_set_free(rs); 2994 2995 return r; 2996 } 2997 2998 static void raid_dtr(struct dm_target *ti) 2999 { 3000 struct raid_set *rs = ti->private; 3001 3002 list_del_init(&rs->callbacks.list); 3003 md_stop(&rs->md); 3004 raid_set_free(rs); 3005 } 3006 3007 static int raid_map(struct dm_target *ti, struct bio *bio) 3008 { 3009 struct raid_set *rs = ti->private; 3010 struct mddev *mddev = &rs->md; 3011 3012 /* 3013 * If we're reshaping to add disk(s)), ti->len and 3014 * mddev->array_sectors will differ during the process 3015 * (ti->len > mddev->array_sectors), so we have to requeue 3016 * bios with addresses > mddev->array_sectors here or 3017 * there will occur accesses past EOD of the component 3018 * data images thus erroring the raid set. 3019 */ 3020 if (unlikely(bio_end_sector(bio) > mddev->array_sectors)) 3021 return DM_MAPIO_REQUEUE; 3022 3023 mddev->pers->make_request(mddev, bio); 3024 3025 return DM_MAPIO_SUBMITTED; 3026 } 3027 3028 /* Return string describing the current sync action of @mddev */ 3029 static const char *decipher_sync_action(struct mddev *mddev) 3030 { 3031 if (test_bit(MD_RECOVERY_FROZEN, &mddev->recovery)) 3032 return "frozen"; 3033 3034 if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) || 3035 (!mddev->ro && test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))) { 3036 if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)) 3037 return "reshape"; 3038 3039 if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) { 3040 if (!test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) 3041 return "resync"; 3042 else if (test_bit(MD_RECOVERY_CHECK, &mddev->recovery)) 3043 return "check"; 3044 return "repair"; 3045 } 3046 3047 if (test_bit(MD_RECOVERY_RECOVER, &mddev->recovery)) 3048 return "recover"; 3049 } 3050 3051 return "idle"; 3052 } 3053 3054 /* 3055 * Return status string @rdev 3056 * 3057 * Status characters: 3058 * 3059 * 'D' = Dead/Failed device 3060 * 'a' = Alive but not in-sync 3061 * 'A' = Alive and in-sync 3062 */ 3063 static const char *__raid_dev_status(struct md_rdev *rdev, bool array_in_sync) 3064 { 3065 if (test_bit(Faulty, &rdev->flags)) 3066 return "D"; 3067 else if (!array_in_sync || !test_bit(In_sync, &rdev->flags)) 3068 return "a"; 3069 else 3070 return "A"; 3071 } 3072 3073 /* Helper to return resync/reshape progress for @rs and @array_in_sync */ 3074 static sector_t rs_get_progress(struct raid_set *rs, 3075 sector_t resync_max_sectors, bool *array_in_sync) 3076 { 3077 sector_t r, recovery_cp, curr_resync_completed; 3078 struct mddev *mddev = &rs->md; 3079 3080 curr_resync_completed = mddev->curr_resync_completed ?: mddev->recovery_cp; 3081 recovery_cp = mddev->recovery_cp; 3082 *array_in_sync = false; 3083 3084 if (rs_is_raid0(rs)) { 3085 r = resync_max_sectors; 3086 *array_in_sync = true; 3087 3088 } else { 3089 r = mddev->reshape_position; 3090 3091 /* Reshape is relative to the array size */ 3092 if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) || 3093 r != MaxSector) { 3094 if (r == MaxSector) { 3095 *array_in_sync = true; 3096 r = resync_max_sectors; 3097 } else { 3098 /* Got to reverse on backward reshape */ 3099 if (mddev->reshape_backwards) 3100 r = mddev->array_sectors - r; 3101 3102 /* Devide by # of data stripes */ 3103 sector_div(r, mddev_data_stripes(rs)); 3104 } 3105 3106 /* Sync is relative to the component device size */ 3107 } else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery)) 3108 r = curr_resync_completed; 3109 else 3110 r = recovery_cp; 3111 3112 if (r == MaxSector) { 3113 /* 3114 * Sync complete. 3115 */ 3116 *array_in_sync = true; 3117 r = resync_max_sectors; 3118 } else if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) { 3119 /* 3120 * If "check" or "repair" is occurring, the raid set has 3121 * undergone an initial sync and the health characters 3122 * should not be 'a' anymore. 3123 */ 3124 *array_in_sync = true; 3125 } else { 3126 struct md_rdev *rdev; 3127 3128 /* 3129 * The raid set may be doing an initial sync, or it may 3130 * be rebuilding individual components. If all the 3131 * devices are In_sync, then it is the raid set that is 3132 * being initialized. 3133 */ 3134 rdev_for_each(rdev, mddev) 3135 if (!test_bit(In_sync, &rdev->flags)) 3136 *array_in_sync = true; 3137 #if 0 3138 r = 0; /* HM FIXME: TESTME: https://bugzilla.redhat.com/show_bug.cgi?id=1210637 ? */ 3139 #endif 3140 } 3141 } 3142 3143 return r; 3144 } 3145 3146 /* Helper to return @dev name or "-" if !@dev */ 3147 static const char *__get_dev_name(struct dm_dev *dev) 3148 { 3149 return dev ? dev->name : "-"; 3150 } 3151 3152 static void raid_status(struct dm_target *ti, status_type_t type, 3153 unsigned int status_flags, char *result, unsigned int maxlen) 3154 { 3155 struct raid_set *rs = ti->private; 3156 struct mddev *mddev = &rs->md; 3157 struct r5conf *conf = mddev->private; 3158 int i, max_nr_stripes = conf ? conf->max_nr_stripes : 0; 3159 bool array_in_sync; 3160 unsigned int raid_param_cnt = 1; /* at least 1 for chunksize */ 3161 unsigned int sz = 0; 3162 unsigned int rebuild_disks; 3163 unsigned int write_mostly_params = 0; 3164 sector_t progress, resync_max_sectors, resync_mismatches; 3165 const char *sync_action; 3166 struct raid_type *rt; 3167 struct md_rdev *rdev; 3168 3169 switch (type) { 3170 case STATUSTYPE_INFO: 3171 /* *Should* always succeed */ 3172 rt = get_raid_type_by_ll(mddev->new_level, mddev->new_layout); 3173 if (!rt) 3174 return; 3175 3176 DMEMIT("%s %d ", rt->name, mddev->raid_disks); 3177 3178 /* Access most recent mddev properties for status output */ 3179 smp_rmb(); 3180 /* Get sensible max sectors even if raid set not yet started */ 3181 resync_max_sectors = test_bit(RT_FLAG_RS_PRERESUMED, &rs->runtime_flags) ? 3182 mddev->resync_max_sectors : mddev->dev_sectors; 3183 progress = rs_get_progress(rs, resync_max_sectors, &array_in_sync); 3184 resync_mismatches = (mddev->last_sync_action && !strcasecmp(mddev->last_sync_action, "check")) ? 3185 atomic64_read(&mddev->resync_mismatches) : 0; 3186 sync_action = decipher_sync_action(&rs->md); 3187 3188 /* HM FIXME: do we want another state char for raid0? It shows 'D' or 'A' now */ 3189 rdev_for_each(rdev, mddev) 3190 DMEMIT(__raid_dev_status(rdev, array_in_sync)); 3191 3192 /* 3193 * In-sync/Reshape ratio: 3194 * The in-sync ratio shows the progress of: 3195 * - Initializing the raid set 3196 * - Rebuilding a subset of devices of the raid set 3197 * The user can distinguish between the two by referring 3198 * to the status characters. 3199 * 3200 * The reshape ratio shows the progress of 3201 * changing the raid layout or the number of 3202 * disks of a raid set 3203 */ 3204 DMEMIT(" %llu/%llu", (unsigned long long) progress, 3205 (unsigned long long) resync_max_sectors); 3206 3207 /* 3208 * v1.5.0+: 3209 * 3210 * Sync action: 3211 * See Documentation/device-mapper/dm-raid.txt for 3212 * information on each of these states. 3213 */ 3214 DMEMIT(" %s", sync_action); 3215 3216 /* 3217 * v1.5.0+: 3218 * 3219 * resync_mismatches/mismatch_cnt 3220 * This field shows the number of discrepancies found when 3221 * performing a "check" of the raid set. 3222 */ 3223 DMEMIT(" %llu", (unsigned long long) resync_mismatches); 3224 3225 /* 3226 * v1.9.0+: 3227 * 3228 * data_offset (needed for out of space reshaping) 3229 * This field shows the data offset into the data 3230 * image LV where the first stripes data starts. 3231 * 3232 * We keep data_offset equal on all raid disks of the set, 3233 * so retrieving it from the first raid disk is sufficient. 3234 */ 3235 DMEMIT(" %llu", (unsigned long long) rs->dev[0].rdev.data_offset); 3236 break; 3237 3238 case STATUSTYPE_TABLE: 3239 /* Report the table line string you would use to construct this raid set */ 3240 3241 /* Calculate raid parameter count */ 3242 for (i = 0; i < rs->raid_disks; i++) 3243 if (test_bit(WriteMostly, &rs->dev[i].rdev.flags)) 3244 write_mostly_params += 2; 3245 rebuild_disks = memweight(rs->rebuild_disks, DISKS_ARRAY_ELEMS * sizeof(*rs->rebuild_disks)); 3246 raid_param_cnt += rebuild_disks * 2 + 3247 write_mostly_params + 3248 hweight32(rs->ctr_flags & CTR_FLAG_OPTIONS_NO_ARGS) + 3249 hweight32(rs->ctr_flags & CTR_FLAG_OPTIONS_ONE_ARG) * 2; 3250 /* Emit table line */ 3251 DMEMIT("%s %u %u", rs->raid_type->name, raid_param_cnt, mddev->new_chunk_sectors); 3252 if (test_bit(__CTR_FLAG_RAID10_FORMAT, &rs->ctr_flags)) 3253 DMEMIT(" %s %s", dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_FORMAT), 3254 raid10_md_layout_to_format(mddev->layout)); 3255 if (test_bit(__CTR_FLAG_RAID10_COPIES, &rs->ctr_flags)) 3256 DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_COPIES), 3257 raid10_md_layout_to_copies(mddev->layout)); 3258 if (test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) 3259 DMEMIT(" %s", dm_raid_arg_name_by_flag(CTR_FLAG_NOSYNC)); 3260 if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags)) 3261 DMEMIT(" %s", dm_raid_arg_name_by_flag(CTR_FLAG_SYNC)); 3262 if (test_bit(__CTR_FLAG_REGION_SIZE, &rs->ctr_flags)) 3263 DMEMIT(" %s %llu", dm_raid_arg_name_by_flag(CTR_FLAG_REGION_SIZE), 3264 (unsigned long long) to_sector(mddev->bitmap_info.chunksize)); 3265 if (test_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags)) 3266 DMEMIT(" %s %llu", dm_raid_arg_name_by_flag(CTR_FLAG_DATA_OFFSET), 3267 (unsigned long long) rs->data_offset); 3268 if (test_bit(__CTR_FLAG_DAEMON_SLEEP, &rs->ctr_flags)) 3269 DMEMIT(" %s %lu", dm_raid_arg_name_by_flag(CTR_FLAG_DAEMON_SLEEP), 3270 mddev->bitmap_info.daemon_sleep); 3271 if (test_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags)) 3272 DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_DELTA_DISKS), 3273 max(rs->delta_disks, mddev->delta_disks)); 3274 if (test_bit(__CTR_FLAG_STRIPE_CACHE, &rs->ctr_flags)) 3275 DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_STRIPE_CACHE), 3276 max_nr_stripes); 3277 if (rebuild_disks) 3278 for (i = 0; i < rs->raid_disks; i++) 3279 if (test_bit(rs->dev[i].rdev.raid_disk, (void *) rs->rebuild_disks)) 3280 DMEMIT(" %s %u", dm_raid_arg_name_by_flag(CTR_FLAG_REBUILD), 3281 rs->dev[i].rdev.raid_disk); 3282 if (write_mostly_params) 3283 for (i = 0; i < rs->raid_disks; i++) 3284 if (test_bit(WriteMostly, &rs->dev[i].rdev.flags)) 3285 DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_WRITE_MOSTLY), 3286 rs->dev[i].rdev.raid_disk); 3287 if (test_bit(__CTR_FLAG_MAX_WRITE_BEHIND, &rs->ctr_flags)) 3288 DMEMIT(" %s %lu", dm_raid_arg_name_by_flag(CTR_FLAG_MAX_WRITE_BEHIND), 3289 mddev->bitmap_info.max_write_behind); 3290 if (test_bit(__CTR_FLAG_MAX_RECOVERY_RATE, &rs->ctr_flags)) 3291 DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_MAX_RECOVERY_RATE), 3292 mddev->sync_speed_max); 3293 if (test_bit(__CTR_FLAG_MIN_RECOVERY_RATE, &rs->ctr_flags)) 3294 DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_MIN_RECOVERY_RATE), 3295 mddev->sync_speed_min); 3296 DMEMIT(" %d", rs->raid_disks); 3297 for (i = 0; i < rs->raid_disks; i++) 3298 DMEMIT(" %s %s", __get_dev_name(rs->dev[i].meta_dev), 3299 __get_dev_name(rs->dev[i].data_dev)); 3300 } 3301 } 3302 3303 static int raid_message(struct dm_target *ti, unsigned int argc, char **argv) 3304 { 3305 struct raid_set *rs = ti->private; 3306 struct mddev *mddev = &rs->md; 3307 3308 if (!mddev->pers || !mddev->pers->sync_request) 3309 return -EINVAL; 3310 3311 if (!strcasecmp(argv[0], "frozen")) 3312 set_bit(MD_RECOVERY_FROZEN, &mddev->recovery); 3313 else 3314 clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery); 3315 3316 if (!strcasecmp(argv[0], "idle") || !strcasecmp(argv[0], "frozen")) { 3317 if (mddev->sync_thread) { 3318 set_bit(MD_RECOVERY_INTR, &mddev->recovery); 3319 md_reap_sync_thread(mddev); 3320 } 3321 } else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) || 3322 test_bit(MD_RECOVERY_NEEDED, &mddev->recovery)) 3323 return -EBUSY; 3324 else if (!strcasecmp(argv[0], "resync")) 3325 ; /* MD_RECOVERY_NEEDED set below */ 3326 else if (!strcasecmp(argv[0], "recover")) 3327 set_bit(MD_RECOVERY_RECOVER, &mddev->recovery); 3328 else { 3329 if (!strcasecmp(argv[0], "check")) 3330 set_bit(MD_RECOVERY_CHECK, &mddev->recovery); 3331 else if (!!strcasecmp(argv[0], "repair")) 3332 return -EINVAL; 3333 set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery); 3334 set_bit(MD_RECOVERY_SYNC, &mddev->recovery); 3335 } 3336 if (mddev->ro == 2) { 3337 /* A write to sync_action is enough to justify 3338 * canceling read-auto mode 3339 */ 3340 mddev->ro = 0; 3341 if (!mddev->suspended && mddev->sync_thread) 3342 md_wakeup_thread(mddev->sync_thread); 3343 } 3344 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); 3345 if (!mddev->suspended && mddev->thread) 3346 md_wakeup_thread(mddev->thread); 3347 3348 return 0; 3349 } 3350 3351 static int raid_iterate_devices(struct dm_target *ti, 3352 iterate_devices_callout_fn fn, void *data) 3353 { 3354 struct raid_set *rs = ti->private; 3355 unsigned int i; 3356 int r = 0; 3357 3358 for (i = 0; !r && i < rs->md.raid_disks; i++) 3359 if (rs->dev[i].data_dev) 3360 r = fn(ti, 3361 rs->dev[i].data_dev, 3362 0, /* No offset on data devs */ 3363 rs->md.dev_sectors, 3364 data); 3365 3366 return r; 3367 } 3368 3369 static void raid_io_hints(struct dm_target *ti, struct queue_limits *limits) 3370 { 3371 struct raid_set *rs = ti->private; 3372 unsigned int chunk_size = to_bytes(rs->md.chunk_sectors); 3373 3374 blk_limits_io_min(limits, chunk_size); 3375 blk_limits_io_opt(limits, chunk_size * mddev_data_stripes(rs)); 3376 } 3377 3378 static void raid_presuspend(struct dm_target *ti) 3379 { 3380 struct raid_set *rs = ti->private; 3381 3382 md_stop_writes(&rs->md); 3383 } 3384 3385 static void raid_postsuspend(struct dm_target *ti) 3386 { 3387 struct raid_set *rs = ti->private; 3388 3389 if (test_and_clear_bit(RT_FLAG_RS_RESUMED, &rs->runtime_flags)) { 3390 if (!rs->md.suspended) 3391 mddev_suspend(&rs->md); 3392 rs->md.ro = 1; 3393 } 3394 } 3395 3396 static void attempt_restore_of_faulty_devices(struct raid_set *rs) 3397 { 3398 int i; 3399 uint64_t failed_devices, cleared_failed_devices = 0; 3400 unsigned long flags; 3401 struct dm_raid_superblock *sb; 3402 struct md_rdev *r; 3403 3404 for (i = 0; i < rs->md.raid_disks; i++) { 3405 r = &rs->dev[i].rdev; 3406 if (test_bit(Faulty, &r->flags) && r->sb_page && 3407 sync_page_io(r, 0, r->sb_size, r->sb_page, 3408 REQ_OP_READ, 0, true)) { 3409 DMINFO("Faulty %s device #%d has readable super block." 3410 " Attempting to revive it.", 3411 rs->raid_type->name, i); 3412 3413 /* 3414 * Faulty bit may be set, but sometimes the array can 3415 * be suspended before the personalities can respond 3416 * by removing the device from the array (i.e. calling 3417 * 'hot_remove_disk'). If they haven't yet removed 3418 * the failed device, its 'raid_disk' number will be 3419 * '>= 0' - meaning we must call this function 3420 * ourselves. 3421 */ 3422 if ((r->raid_disk >= 0) && 3423 (r->mddev->pers->hot_remove_disk(r->mddev, r) != 0)) 3424 /* Failed to revive this device, try next */ 3425 continue; 3426 3427 r->raid_disk = i; 3428 r->saved_raid_disk = i; 3429 flags = r->flags; 3430 clear_bit(Faulty, &r->flags); 3431 clear_bit(WriteErrorSeen, &r->flags); 3432 clear_bit(In_sync, &r->flags); 3433 if (r->mddev->pers->hot_add_disk(r->mddev, r)) { 3434 r->raid_disk = -1; 3435 r->saved_raid_disk = -1; 3436 r->flags = flags; 3437 } else { 3438 r->recovery_offset = 0; 3439 cleared_failed_devices |= 1 << i; 3440 } 3441 } 3442 } 3443 if (cleared_failed_devices) { 3444 rdev_for_each(r, &rs->md) { 3445 sb = page_address(r->sb_page); 3446 failed_devices = le64_to_cpu(sb->failed_devices); 3447 failed_devices &= ~cleared_failed_devices; 3448 sb->failed_devices = cpu_to_le64(failed_devices); 3449 } 3450 } 3451 } 3452 3453 static int __load_dirty_region_bitmap(struct raid_set *rs) 3454 { 3455 int r = 0; 3456 3457 /* Try loading the bitmap unless "raid0", which does not have one */ 3458 if (!rs_is_raid0(rs) && 3459 !test_and_set_bit(RT_FLAG_RS_BITMAP_LOADED, &rs->runtime_flags)) { 3460 r = bitmap_load(&rs->md); 3461 if (r) 3462 DMERR("Failed to load bitmap"); 3463 } 3464 3465 return r; 3466 } 3467 3468 /* Enforce updating all superblocks */ 3469 static void rs_update_sbs(struct raid_set *rs) 3470 { 3471 struct mddev *mddev = &rs->md; 3472 int ro = mddev->ro; 3473 3474 set_bit(MD_CHANGE_DEVS, &mddev->flags); 3475 mddev->ro = 0; 3476 md_update_sb(mddev, 1); 3477 mddev->ro = ro; 3478 } 3479 3480 /* 3481 * Reshape changes raid algorithm of @rs to new one within personality 3482 * (e.g. raid6_zr -> raid6_nc), changes stripe size, adds/removes 3483 * disks from a raid set thus growing/shrinking it or resizes the set 3484 * 3485 * Call mddev_lock_nointr() before! 3486 */ 3487 static int rs_start_reshape(struct raid_set *rs) 3488 { 3489 int r; 3490 struct mddev *mddev = &rs->md; 3491 struct md_personality *pers = mddev->pers; 3492 3493 r = rs_setup_reshape(rs); 3494 if (r) 3495 return r; 3496 3497 /* Need to be resumed to be able to start reshape, recovery is frozen until raid_resume() though */ 3498 if (mddev->suspended) 3499 mddev_resume(mddev); 3500 3501 /* 3502 * Check any reshape constraints enforced by the personalility 3503 * 3504 * May as well already kick the reshape off so that * pers->start_reshape() becomes optional. 3505 */ 3506 r = pers->check_reshape(mddev); 3507 if (r) { 3508 rs->ti->error = "pers->check_reshape() failed"; 3509 return r; 3510 } 3511 3512 /* 3513 * Personality may not provide start reshape method in which 3514 * case check_reshape above has already covered everything 3515 */ 3516 if (pers->start_reshape) { 3517 r = pers->start_reshape(mddev); 3518 if (r) { 3519 rs->ti->error = "pers->start_reshape() failed"; 3520 return r; 3521 } 3522 } 3523 3524 /* Suspend because a resume will happen in raid_resume() */ 3525 if (!mddev->suspended) 3526 mddev_suspend(mddev); 3527 3528 /* 3529 * Now reshape got set up, update superblocks to 3530 * reflect the fact so that a table reload will 3531 * access proper superblock content in the ctr. 3532 */ 3533 rs_update_sbs(rs); 3534 3535 return 0; 3536 } 3537 3538 static int raid_preresume(struct dm_target *ti) 3539 { 3540 int r; 3541 struct raid_set *rs = ti->private; 3542 struct mddev *mddev = &rs->md; 3543 3544 /* This is a resume after a suspend of the set -> it's already started */ 3545 if (test_and_set_bit(RT_FLAG_RS_PRERESUMED, &rs->runtime_flags)) 3546 return 0; 3547 3548 /* 3549 * The superblocks need to be updated on disk if the 3550 * array is new or new devices got added (thus zeroed 3551 * out by userspace) or __load_dirty_region_bitmap 3552 * will overwrite them in core with old data or fail. 3553 */ 3554 if (test_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags)) 3555 rs_update_sbs(rs); 3556 3557 /* 3558 * Disable/enable discard support on raid set after any 3559 * conversion, because devices can have been added 3560 */ 3561 configure_discard_support(rs); 3562 3563 /* Load the bitmap from disk unless raid0 */ 3564 r = __load_dirty_region_bitmap(rs); 3565 if (r) 3566 return r; 3567 3568 /* Resize bitmap to adjust to changed region size (aka MD bitmap chunksize) */ 3569 if (test_bit(RT_FLAG_RS_BITMAP_LOADED, &rs->runtime_flags) && 3570 mddev->bitmap_info.chunksize != to_bytes(rs->requested_bitmap_chunk_sectors)) { 3571 r = bitmap_resize(mddev->bitmap, mddev->dev_sectors, 3572 to_bytes(rs->requested_bitmap_chunk_sectors), 0); 3573 if (r) 3574 DMERR("Failed to resize bitmap"); 3575 } 3576 3577 /* Check for any resize/reshape on @rs and adjust/initiate */ 3578 /* Be prepared for mddev_resume() in raid_resume() */ 3579 set_bit(MD_RECOVERY_FROZEN, &mddev->recovery); 3580 if (mddev->recovery_cp && mddev->recovery_cp < MaxSector) { 3581 set_bit(MD_RECOVERY_SYNC, &mddev->recovery); 3582 mddev->resync_min = mddev->recovery_cp; 3583 } 3584 3585 rs_set_capacity(rs); 3586 3587 /* Check for any reshape request unless new raid set */ 3588 if (test_and_clear_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags)) { 3589 /* Initiate a reshape. */ 3590 mddev_lock_nointr(mddev); 3591 r = rs_start_reshape(rs); 3592 mddev_unlock(mddev); 3593 if (r) 3594 DMWARN("Failed to check/start reshape, continuing without change"); 3595 r = 0; 3596 } 3597 3598 return r; 3599 } 3600 3601 static void raid_resume(struct dm_target *ti) 3602 { 3603 struct raid_set *rs = ti->private; 3604 struct mddev *mddev = &rs->md; 3605 3606 if (test_and_set_bit(RT_FLAG_RS_RESUMED, &rs->runtime_flags)) { 3607 /* 3608 * A secondary resume while the device is active. 3609 * Take this opportunity to check whether any failed 3610 * devices are reachable again. 3611 */ 3612 attempt_restore_of_faulty_devices(rs); 3613 } else { 3614 mddev->ro = 0; 3615 mddev->in_sync = 0; 3616 3617 /* 3618 * When passing in flags to the ctr, we expect userspace 3619 * to reset them because they made it to the superblocks 3620 * and reload the mapping anyway. 3621 * 3622 * -> only unfreeze recovery in case of a table reload or 3623 * we'll have a bogus recovery/reshape position 3624 * retrieved from the superblock by the ctr because 3625 * the ongoing recovery/reshape will change it after read. 3626 */ 3627 if (!test_bit(RT_FLAG_KEEP_RS_FROZEN, &rs->runtime_flags)) 3628 clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery); 3629 3630 if (mddev->suspended) 3631 mddev_resume(mddev); 3632 } 3633 } 3634 3635 static struct target_type raid_target = { 3636 .name = "raid", 3637 .version = {1, 9, 0}, 3638 .module = THIS_MODULE, 3639 .ctr = raid_ctr, 3640 .dtr = raid_dtr, 3641 .map = raid_map, 3642 .status = raid_status, 3643 .message = raid_message, 3644 .iterate_devices = raid_iterate_devices, 3645 .io_hints = raid_io_hints, 3646 .presuspend = raid_presuspend, 3647 .postsuspend = raid_postsuspend, 3648 .preresume = raid_preresume, 3649 .resume = raid_resume, 3650 }; 3651 3652 static int __init dm_raid_init(void) 3653 { 3654 DMINFO("Loading target version %u.%u.%u", 3655 raid_target.version[0], 3656 raid_target.version[1], 3657 raid_target.version[2]); 3658 return dm_register_target(&raid_target); 3659 } 3660 3661 static void __exit dm_raid_exit(void) 3662 { 3663 dm_unregister_target(&raid_target); 3664 } 3665 3666 module_init(dm_raid_init); 3667 module_exit(dm_raid_exit); 3668 3669 module_param(devices_handle_discard_safely, bool, 0644); 3670 MODULE_PARM_DESC(devices_handle_discard_safely, 3671 "Set to Y if all devices in each array reliably return zeroes on reads from discarded regions"); 3672 3673 MODULE_DESCRIPTION(DM_NAME " raid0/1/10/4/5/6 target"); 3674 MODULE_ALIAS("dm-raid0"); 3675 MODULE_ALIAS("dm-raid1"); 3676 MODULE_ALIAS("dm-raid10"); 3677 MODULE_ALIAS("dm-raid4"); 3678 MODULE_ALIAS("dm-raid5"); 3679 MODULE_ALIAS("dm-raid6"); 3680 MODULE_AUTHOR("Neil Brown <dm-devel@redhat.com>"); 3681 MODULE_AUTHOR("Heinz Mauelshagen <dm-devel@redhat.com>"); 3682 MODULE_LICENSE("GPL"); 3683