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 4 194 195 /* Array elements of 64 bit needed for rebuild/failed disk bits */ 196 #define DISKS_ARRAY_ELEMS ((MAX_RAID_DEVICES + (sizeof(uint64_t) * 8 - 1)) / sizeof(uint64_t) / 8) 197 198 /* 199 * raid set level, layout and chunk sectors backup/restore 200 */ 201 struct rs_layout { 202 int new_level; 203 int new_layout; 204 int new_chunk_sectors; 205 }; 206 207 struct raid_set { 208 struct dm_target *ti; 209 210 uint32_t bitmap_loaded; 211 uint32_t stripe_cache_entries; 212 unsigned long ctr_flags; 213 unsigned long runtime_flags; 214 215 uint64_t rebuild_disks[DISKS_ARRAY_ELEMS]; 216 217 int raid_disks; 218 int delta_disks; 219 int data_offset; 220 int raid10_copies; 221 int requested_bitmap_chunk_sectors; 222 223 struct mddev md; 224 struct raid_type *raid_type; 225 struct dm_target_callbacks callbacks; 226 227 struct raid_dev dev[0]; 228 }; 229 230 static void rs_config_backup(struct raid_set *rs, struct rs_layout *l) 231 { 232 struct mddev *mddev = &rs->md; 233 234 l->new_level = mddev->new_level; 235 l->new_layout = mddev->new_layout; 236 l->new_chunk_sectors = mddev->new_chunk_sectors; 237 } 238 239 static void rs_config_restore(struct raid_set *rs, struct rs_layout *l) 240 { 241 struct mddev *mddev = &rs->md; 242 243 mddev->new_level = l->new_level; 244 mddev->new_layout = l->new_layout; 245 mddev->new_chunk_sectors = l->new_chunk_sectors; 246 } 247 248 /* raid10 algorithms (i.e. formats) */ 249 #define ALGORITHM_RAID10_DEFAULT 0 250 #define ALGORITHM_RAID10_NEAR 1 251 #define ALGORITHM_RAID10_OFFSET 2 252 #define ALGORITHM_RAID10_FAR 3 253 254 /* Supported raid types and properties. */ 255 static struct raid_type { 256 const char *name; /* RAID algorithm. */ 257 const char *descr; /* Descriptor text for logging. */ 258 const unsigned int parity_devs; /* # of parity devices. */ 259 const unsigned int minimal_devs;/* minimal # of devices in set. */ 260 const unsigned int level; /* RAID level. */ 261 const unsigned int algorithm; /* RAID algorithm. */ 262 } raid_types[] = { 263 {"raid0", "raid0 (striping)", 0, 2, 0, 0 /* NONE */}, 264 {"raid1", "raid1 (mirroring)", 0, 2, 1, 0 /* NONE */}, 265 {"raid10_far", "raid10 far (striped mirrors)", 0, 2, 10, ALGORITHM_RAID10_FAR}, 266 {"raid10_offset", "raid10 offset (striped mirrors)", 0, 2, 10, ALGORITHM_RAID10_OFFSET}, 267 {"raid10_near", "raid10 near (striped mirrors)", 0, 2, 10, ALGORITHM_RAID10_NEAR}, 268 {"raid10", "raid10 (striped mirrors)", 0, 2, 10, ALGORITHM_RAID10_DEFAULT}, 269 {"raid4", "raid4 (dedicated last parity disk)", 1, 2, 4, ALGORITHM_PARITY_N}, /* raid4 layout = raid5_n */ 270 {"raid5_n", "raid5 (dedicated last parity disk)", 1, 2, 5, ALGORITHM_PARITY_N}, 271 {"raid5_ls", "raid5 (left symmetric)", 1, 2, 5, ALGORITHM_LEFT_SYMMETRIC}, 272 {"raid5_rs", "raid5 (right symmetric)", 1, 2, 5, ALGORITHM_RIGHT_SYMMETRIC}, 273 {"raid5_la", "raid5 (left asymmetric)", 1, 2, 5, ALGORITHM_LEFT_ASYMMETRIC}, 274 {"raid5_ra", "raid5 (right asymmetric)", 1, 2, 5, ALGORITHM_RIGHT_ASYMMETRIC}, 275 {"raid6_zr", "raid6 (zero restart)", 2, 4, 6, ALGORITHM_ROTATING_ZERO_RESTART}, 276 {"raid6_nr", "raid6 (N restart)", 2, 4, 6, ALGORITHM_ROTATING_N_RESTART}, 277 {"raid6_nc", "raid6 (N continue)", 2, 4, 6, ALGORITHM_ROTATING_N_CONTINUE}, 278 {"raid6_n_6", "raid6 (dedicated parity/Q n/6)", 2, 4, 6, ALGORITHM_PARITY_N_6}, 279 {"raid6_ls_6", "raid6 (left symmetric dedicated Q 6)", 2, 4, 6, ALGORITHM_LEFT_SYMMETRIC_6}, 280 {"raid6_rs_6", "raid6 (right symmetric dedicated Q 6)", 2, 4, 6, ALGORITHM_RIGHT_SYMMETRIC_6}, 281 {"raid6_la_6", "raid6 (left asymmetric dedicated Q 6)", 2, 4, 6, ALGORITHM_LEFT_ASYMMETRIC_6}, 282 {"raid6_ra_6", "raid6 (right asymmetric dedicated Q 6)", 2, 4, 6, ALGORITHM_RIGHT_ASYMMETRIC_6} 283 }; 284 285 /* True, if @v is in inclusive range [@min, @max] */ 286 static bool __within_range(long v, long min, long max) 287 { 288 return v >= min && v <= max; 289 } 290 291 /* All table line arguments are defined here */ 292 static struct arg_name_flag { 293 const unsigned long flag; 294 const char *name; 295 } __arg_name_flags[] = { 296 { CTR_FLAG_SYNC, "sync"}, 297 { CTR_FLAG_NOSYNC, "nosync"}, 298 { CTR_FLAG_REBUILD, "rebuild"}, 299 { CTR_FLAG_DAEMON_SLEEP, "daemon_sleep"}, 300 { CTR_FLAG_MIN_RECOVERY_RATE, "min_recovery_rate"}, 301 { CTR_FLAG_MAX_RECOVERY_RATE, "max_recovery_rate"}, 302 { CTR_FLAG_MAX_WRITE_BEHIND, "max_write_behind"}, 303 { CTR_FLAG_WRITE_MOSTLY, "write_mostly"}, 304 { CTR_FLAG_STRIPE_CACHE, "stripe_cache"}, 305 { CTR_FLAG_REGION_SIZE, "region_size"}, 306 { CTR_FLAG_RAID10_COPIES, "raid10_copies"}, 307 { CTR_FLAG_RAID10_FORMAT, "raid10_format"}, 308 { CTR_FLAG_DATA_OFFSET, "data_offset"}, 309 { CTR_FLAG_DELTA_DISKS, "delta_disks"}, 310 { CTR_FLAG_RAID10_USE_NEAR_SETS, "raid10_use_near_sets"}, 311 }; 312 313 /* Return argument name string for given @flag */ 314 static const char *dm_raid_arg_name_by_flag(const uint32_t flag) 315 { 316 if (hweight32(flag) == 1) { 317 struct arg_name_flag *anf = __arg_name_flags + ARRAY_SIZE(__arg_name_flags); 318 319 while (anf-- > __arg_name_flags) 320 if (flag & anf->flag) 321 return anf->name; 322 323 } else 324 DMERR("%s called with more than one flag!", __func__); 325 326 return NULL; 327 } 328 329 /* 330 * Bool helpers to test for various raid levels of a raid set. 331 * It's level as reported by the superblock rather than 332 * the requested raid_type passed to the constructor. 333 */ 334 /* Return true, if raid set in @rs is raid0 */ 335 static bool rs_is_raid0(struct raid_set *rs) 336 { 337 return !rs->md.level; 338 } 339 340 /* Return true, if raid set in @rs is raid1 */ 341 static bool rs_is_raid1(struct raid_set *rs) 342 { 343 return rs->md.level == 1; 344 } 345 346 /* Return true, if raid set in @rs is raid10 */ 347 static bool rs_is_raid10(struct raid_set *rs) 348 { 349 return rs->md.level == 10; 350 } 351 352 /* Return true, if raid set in @rs is level 6 */ 353 static bool rs_is_raid6(struct raid_set *rs) 354 { 355 return rs->md.level == 6; 356 } 357 358 /* Return true, if raid set in @rs is level 4, 5 or 6 */ 359 static bool rs_is_raid456(struct raid_set *rs) 360 { 361 return __within_range(rs->md.level, 4, 6); 362 } 363 364 /* Return true, if raid set in @rs is reshapable */ 365 static bool __is_raid10_far(int layout); 366 static bool rs_is_reshapable(struct raid_set *rs) 367 { 368 return rs_is_raid456(rs) || 369 (rs_is_raid10(rs) && !__is_raid10_far(rs->md.new_layout)); 370 } 371 372 /* Return true, if raid set in @rs is recovering */ 373 static bool rs_is_recovering(struct raid_set *rs) 374 { 375 return rs->md.recovery_cp < rs->dev[0].rdev.sectors; 376 } 377 378 /* Return true, if raid set in @rs is reshaping */ 379 static bool rs_is_reshaping(struct raid_set *rs) 380 { 381 return rs->md.reshape_position != MaxSector; 382 } 383 384 /* 385 * bool helpers to test for various raid levels of a raid type @rt 386 */ 387 388 /* Return true, if raid type in @rt is raid0 */ 389 static bool rt_is_raid0(struct raid_type *rt) 390 { 391 return !rt->level; 392 } 393 394 /* Return true, if raid type in @rt is raid1 */ 395 static bool rt_is_raid1(struct raid_type *rt) 396 { 397 return rt->level == 1; 398 } 399 400 /* Return true, if raid type in @rt is raid10 */ 401 static bool rt_is_raid10(struct raid_type *rt) 402 { 403 return rt->level == 10; 404 } 405 406 /* Return true, if raid type in @rt is raid4/5 */ 407 static bool rt_is_raid45(struct raid_type *rt) 408 { 409 return __within_range(rt->level, 4, 5); 410 } 411 412 /* Return true, if raid type in @rt is raid6 */ 413 static bool rt_is_raid6(struct raid_type *rt) 414 { 415 return rt->level == 6; 416 } 417 418 /* Return true, if raid type in @rt is raid4/5/6 */ 419 static bool rt_is_raid456(struct raid_type *rt) 420 { 421 return __within_range(rt->level, 4, 6); 422 } 423 /* END: raid level bools */ 424 425 /* Return valid ctr flags for the raid level of @rs */ 426 static unsigned long __valid_flags(struct raid_set *rs) 427 { 428 if (rt_is_raid0(rs->raid_type)) 429 return RAID0_VALID_FLAGS; 430 else if (rt_is_raid1(rs->raid_type)) 431 return RAID1_VALID_FLAGS; 432 else if (rt_is_raid10(rs->raid_type)) 433 return RAID10_VALID_FLAGS; 434 else if (rt_is_raid45(rs->raid_type)) 435 return RAID45_VALID_FLAGS; 436 else if (rt_is_raid6(rs->raid_type)) 437 return RAID6_VALID_FLAGS; 438 439 return 0; 440 } 441 442 /* 443 * Check for valid flags set on @rs 444 * 445 * Has to be called after parsing of the ctr flags! 446 */ 447 static int rs_check_for_valid_flags(struct raid_set *rs) 448 { 449 if (rs->ctr_flags & ~__valid_flags(rs)) { 450 rs->ti->error = "Invalid flags combination"; 451 return -EINVAL; 452 } 453 454 return 0; 455 } 456 457 /* MD raid10 bit definitions and helpers */ 458 #define RAID10_OFFSET (1 << 16) /* stripes with data copies area adjacent on devices */ 459 #define RAID10_BROCKEN_USE_FAR_SETS (1 << 17) /* Broken in raid10.c: use sets instead of whole stripe rotation */ 460 #define RAID10_USE_FAR_SETS (1 << 18) /* Use sets instead of whole stripe rotation */ 461 #define RAID10_FAR_COPIES_SHIFT 8 /* raid10 # far copies shift (2nd byte of layout) */ 462 463 /* Return md raid10 near copies for @layout */ 464 static unsigned int __raid10_near_copies(int layout) 465 { 466 return layout & 0xFF; 467 } 468 469 /* Return md raid10 far copies for @layout */ 470 static unsigned int __raid10_far_copies(int layout) 471 { 472 return __raid10_near_copies(layout >> RAID10_FAR_COPIES_SHIFT); 473 } 474 475 /* Return true if md raid10 offset for @layout */ 476 static bool __is_raid10_offset(int layout) 477 { 478 return !!(layout & RAID10_OFFSET); 479 } 480 481 /* Return true if md raid10 near for @layout */ 482 static bool __is_raid10_near(int layout) 483 { 484 return !__is_raid10_offset(layout) && __raid10_near_copies(layout) > 1; 485 } 486 487 /* Return true if md raid10 far for @layout */ 488 static bool __is_raid10_far(int layout) 489 { 490 return !__is_raid10_offset(layout) && __raid10_far_copies(layout) > 1; 491 } 492 493 /* Return md raid10 layout string for @layout */ 494 static const char *raid10_md_layout_to_format(int layout) 495 { 496 /* 497 * Bit 16 stands for "offset" 498 * (i.e. adjacent stripes hold copies) 499 * 500 * Refer to MD's raid10.c for details 501 */ 502 if (__is_raid10_offset(layout)) 503 return "offset"; 504 505 if (__raid10_near_copies(layout) > 1) 506 return "near"; 507 508 WARN_ON(__raid10_far_copies(layout) < 2); 509 510 return "far"; 511 } 512 513 /* Return md raid10 algorithm for @name */ 514 static int raid10_name_to_format(const char *name) 515 { 516 if (!strcasecmp(name, "near")) 517 return ALGORITHM_RAID10_NEAR; 518 else if (!strcasecmp(name, "offset")) 519 return ALGORITHM_RAID10_OFFSET; 520 else if (!strcasecmp(name, "far")) 521 return ALGORITHM_RAID10_FAR; 522 523 return -EINVAL; 524 } 525 526 /* Return md raid10 copies for @layout */ 527 static unsigned int raid10_md_layout_to_copies(int layout) 528 { 529 return max(__raid10_near_copies(layout), __raid10_far_copies(layout)); 530 } 531 532 /* Return md raid10 format id for @format string */ 533 static int raid10_format_to_md_layout(struct raid_set *rs, 534 unsigned int algorithm, 535 unsigned int copies) 536 { 537 unsigned int n = 1, f = 1, r = 0; 538 539 /* 540 * MD resilienece flaw: 541 * 542 * enabling use_far_sets for far/offset formats causes copies 543 * to be colocated on the same devs together with their origins! 544 * 545 * -> disable it for now in the definition above 546 */ 547 if (algorithm == ALGORITHM_RAID10_DEFAULT || 548 algorithm == ALGORITHM_RAID10_NEAR) 549 n = copies; 550 551 else if (algorithm == ALGORITHM_RAID10_OFFSET) { 552 f = copies; 553 r = RAID10_OFFSET; 554 if (!test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags)) 555 r |= RAID10_USE_FAR_SETS; 556 557 } else if (algorithm == ALGORITHM_RAID10_FAR) { 558 f = copies; 559 r = !RAID10_OFFSET; 560 if (!test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags)) 561 r |= RAID10_USE_FAR_SETS; 562 563 } else 564 return -EINVAL; 565 566 return r | (f << RAID10_FAR_COPIES_SHIFT) | n; 567 } 568 /* END: MD raid10 bit definitions and helpers */ 569 570 /* Check for any of the raid10 algorithms */ 571 static bool __got_raid10(struct raid_type *rtp, const int layout) 572 { 573 if (rtp->level == 10) { 574 switch (rtp->algorithm) { 575 case ALGORITHM_RAID10_DEFAULT: 576 case ALGORITHM_RAID10_NEAR: 577 return __is_raid10_near(layout); 578 case ALGORITHM_RAID10_OFFSET: 579 return __is_raid10_offset(layout); 580 case ALGORITHM_RAID10_FAR: 581 return __is_raid10_far(layout); 582 default: 583 break; 584 } 585 } 586 587 return false; 588 } 589 590 /* Return raid_type for @name */ 591 static struct raid_type *get_raid_type(const char *name) 592 { 593 struct raid_type *rtp = raid_types + ARRAY_SIZE(raid_types); 594 595 while (rtp-- > raid_types) 596 if (!strcasecmp(rtp->name, name)) 597 return rtp; 598 599 return NULL; 600 } 601 602 /* Return raid_type for @name based derived from @level and @layout */ 603 static struct raid_type *get_raid_type_by_ll(const int level, const int layout) 604 { 605 struct raid_type *rtp = raid_types + ARRAY_SIZE(raid_types); 606 607 while (rtp-- > raid_types) { 608 /* RAID10 special checks based on @layout flags/properties */ 609 if (rtp->level == level && 610 (__got_raid10(rtp, layout) || rtp->algorithm == layout)) 611 return rtp; 612 } 613 614 return NULL; 615 } 616 617 /* 618 * Conditionally change bdev capacity of @rs 619 * in case of a disk add/remove reshape 620 */ 621 static void rs_set_capacity(struct raid_set *rs) 622 { 623 struct mddev *mddev = &rs->md; 624 struct md_rdev *rdev; 625 struct gendisk *gendisk = dm_disk(dm_table_get_md(rs->ti->table)); 626 627 /* 628 * raid10 sets rdev->sector to the device size, which 629 * is unintended in case of out-of-place reshaping 630 */ 631 rdev_for_each(rdev, mddev) 632 rdev->sectors = mddev->dev_sectors; 633 634 set_capacity(gendisk, mddev->array_sectors); 635 revalidate_disk(gendisk); 636 } 637 638 /* 639 * Set the mddev properties in @rs to the current 640 * ones retrieved from the freshest superblock 641 */ 642 static void rs_set_cur(struct raid_set *rs) 643 { 644 struct mddev *mddev = &rs->md; 645 646 mddev->new_level = mddev->level; 647 mddev->new_layout = mddev->layout; 648 mddev->new_chunk_sectors = mddev->chunk_sectors; 649 } 650 651 /* 652 * Set the mddev properties in @rs to the new 653 * ones requested by the ctr 654 */ 655 static void rs_set_new(struct raid_set *rs) 656 { 657 struct mddev *mddev = &rs->md; 658 659 mddev->level = mddev->new_level; 660 mddev->layout = mddev->new_layout; 661 mddev->chunk_sectors = mddev->new_chunk_sectors; 662 mddev->raid_disks = rs->raid_disks; 663 mddev->delta_disks = 0; 664 } 665 666 static struct raid_set *raid_set_alloc(struct dm_target *ti, struct raid_type *raid_type, 667 unsigned int raid_devs) 668 { 669 unsigned int i; 670 struct raid_set *rs; 671 672 if (raid_devs <= raid_type->parity_devs) { 673 ti->error = "Insufficient number of devices"; 674 return ERR_PTR(-EINVAL); 675 } 676 677 rs = kzalloc(sizeof(*rs) + raid_devs * sizeof(rs->dev[0]), GFP_KERNEL); 678 if (!rs) { 679 ti->error = "Cannot allocate raid context"; 680 return ERR_PTR(-ENOMEM); 681 } 682 683 mddev_init(&rs->md); 684 685 rs->raid_disks = raid_devs; 686 rs->delta_disks = 0; 687 688 rs->ti = ti; 689 rs->raid_type = raid_type; 690 rs->stripe_cache_entries = 256; 691 rs->md.raid_disks = raid_devs; 692 rs->md.level = raid_type->level; 693 rs->md.new_level = rs->md.level; 694 rs->md.layout = raid_type->algorithm; 695 rs->md.new_layout = rs->md.layout; 696 rs->md.delta_disks = 0; 697 rs->md.recovery_cp = MaxSector; 698 699 for (i = 0; i < raid_devs; i++) 700 md_rdev_init(&rs->dev[i].rdev); 701 702 /* 703 * Remaining items to be initialized by further RAID params: 704 * rs->md.persistent 705 * rs->md.external 706 * rs->md.chunk_sectors 707 * rs->md.new_chunk_sectors 708 * rs->md.dev_sectors 709 */ 710 711 return rs; 712 } 713 714 static void raid_set_free(struct raid_set *rs) 715 { 716 int i; 717 718 for (i = 0; i < rs->raid_disks; i++) { 719 if (rs->dev[i].meta_dev) 720 dm_put_device(rs->ti, rs->dev[i].meta_dev); 721 md_rdev_clear(&rs->dev[i].rdev); 722 if (rs->dev[i].data_dev) 723 dm_put_device(rs->ti, rs->dev[i].data_dev); 724 } 725 726 kfree(rs); 727 } 728 729 /* 730 * For every device we have two words 731 * <meta_dev>: meta device name or '-' if missing 732 * <data_dev>: data device name or '-' if missing 733 * 734 * The following are permitted: 735 * - - 736 * - <data_dev> 737 * <meta_dev> <data_dev> 738 * 739 * The following is not allowed: 740 * <meta_dev> - 741 * 742 * This code parses those words. If there is a failure, 743 * the caller must use raid_set_free() to unwind the operations. 744 */ 745 static int parse_dev_params(struct raid_set *rs, struct dm_arg_set *as) 746 { 747 int i; 748 int rebuild = 0; 749 int metadata_available = 0; 750 int r = 0; 751 const char *arg; 752 753 /* Put off the number of raid devices argument to get to dev pairs */ 754 arg = dm_shift_arg(as); 755 if (!arg) 756 return -EINVAL; 757 758 for (i = 0; i < rs->raid_disks; i++) { 759 rs->dev[i].rdev.raid_disk = i; 760 761 rs->dev[i].meta_dev = NULL; 762 rs->dev[i].data_dev = NULL; 763 764 /* 765 * There are no offsets, since there is a separate device 766 * for data and metadata. 767 */ 768 rs->dev[i].rdev.data_offset = 0; 769 rs->dev[i].rdev.mddev = &rs->md; 770 771 arg = dm_shift_arg(as); 772 if (!arg) 773 return -EINVAL; 774 775 if (strcmp(arg, "-")) { 776 r = dm_get_device(rs->ti, arg, dm_table_get_mode(rs->ti->table), 777 &rs->dev[i].meta_dev); 778 if (r) { 779 rs->ti->error = "RAID metadata device lookup failure"; 780 return r; 781 } 782 783 rs->dev[i].rdev.sb_page = alloc_page(GFP_KERNEL); 784 if (!rs->dev[i].rdev.sb_page) { 785 rs->ti->error = "Failed to allocate superblock page"; 786 return -ENOMEM; 787 } 788 } 789 790 arg = dm_shift_arg(as); 791 if (!arg) 792 return -EINVAL; 793 794 if (!strcmp(arg, "-")) { 795 if (!test_bit(In_sync, &rs->dev[i].rdev.flags) && 796 (!rs->dev[i].rdev.recovery_offset)) { 797 rs->ti->error = "Drive designated for rebuild not specified"; 798 return -EINVAL; 799 } 800 801 if (rs->dev[i].meta_dev) { 802 rs->ti->error = "No data device supplied with metadata device"; 803 return -EINVAL; 804 } 805 806 continue; 807 } 808 809 r = dm_get_device(rs->ti, arg, dm_table_get_mode(rs->ti->table), 810 &rs->dev[i].data_dev); 811 if (r) { 812 rs->ti->error = "RAID device lookup failure"; 813 return r; 814 } 815 816 if (rs->dev[i].meta_dev) { 817 metadata_available = 1; 818 rs->dev[i].rdev.meta_bdev = rs->dev[i].meta_dev->bdev; 819 } 820 rs->dev[i].rdev.bdev = rs->dev[i].data_dev->bdev; 821 list_add_tail(&rs->dev[i].rdev.same_set, &rs->md.disks); 822 if (!test_bit(In_sync, &rs->dev[i].rdev.flags)) 823 rebuild++; 824 } 825 826 if (metadata_available) { 827 rs->md.external = 0; 828 rs->md.persistent = 1; 829 rs->md.major_version = 2; 830 } else if (rebuild && !rs->md.recovery_cp) { 831 /* 832 * Without metadata, we will not be able to tell if the array 833 * is in-sync or not - we must assume it is not. Therefore, 834 * it is impossible to rebuild a drive. 835 * 836 * Even if there is metadata, the on-disk information may 837 * indicate that the array is not in-sync and it will then 838 * fail at that time. 839 * 840 * User could specify 'nosync' option if desperate. 841 */ 842 rs->ti->error = "Unable to rebuild drive while array is not in-sync"; 843 return -EINVAL; 844 } 845 846 return 0; 847 } 848 849 /* 850 * validate_region_size 851 * @rs 852 * @region_size: region size in sectors. If 0, pick a size (4MiB default). 853 * 854 * Set rs->md.bitmap_info.chunksize (which really refers to 'region size'). 855 * Ensure that (ti->len/region_size < 2^21) - required by MD bitmap. 856 * 857 * Returns: 0 on success, -EINVAL on failure. 858 */ 859 static int validate_region_size(struct raid_set *rs, unsigned long region_size) 860 { 861 unsigned long min_region_size = rs->ti->len / (1 << 21); 862 863 if (rs_is_raid0(rs)) 864 return 0; 865 866 if (!region_size) { 867 /* 868 * Choose a reasonable default. All figures in sectors. 869 */ 870 if (min_region_size > (1 << 13)) { 871 /* If not a power of 2, make it the next power of 2 */ 872 region_size = roundup_pow_of_two(min_region_size); 873 DMINFO("Choosing default region size of %lu sectors", 874 region_size); 875 } else { 876 DMINFO("Choosing default region size of 4MiB"); 877 region_size = 1 << 13; /* sectors */ 878 } 879 } else { 880 /* 881 * Validate user-supplied value. 882 */ 883 if (region_size > rs->ti->len) { 884 rs->ti->error = "Supplied region size is too large"; 885 return -EINVAL; 886 } 887 888 if (region_size < min_region_size) { 889 DMERR("Supplied region_size (%lu sectors) below minimum (%lu)", 890 region_size, min_region_size); 891 rs->ti->error = "Supplied region size is too small"; 892 return -EINVAL; 893 } 894 895 if (!is_power_of_2(region_size)) { 896 rs->ti->error = "Region size is not a power of 2"; 897 return -EINVAL; 898 } 899 900 if (region_size < rs->md.chunk_sectors) { 901 rs->ti->error = "Region size is smaller than the chunk size"; 902 return -EINVAL; 903 } 904 } 905 906 /* 907 * Convert sectors to bytes. 908 */ 909 rs->md.bitmap_info.chunksize = to_bytes(region_size); 910 911 return 0; 912 } 913 914 /* 915 * validate_raid_redundancy 916 * @rs 917 * 918 * Determine if there are enough devices in the array that haven't 919 * failed (or are being rebuilt) to form a usable array. 920 * 921 * Returns: 0 on success, -EINVAL on failure. 922 */ 923 static int validate_raid_redundancy(struct raid_set *rs) 924 { 925 unsigned int i, rebuild_cnt = 0; 926 unsigned int rebuilds_per_group = 0, copies; 927 unsigned int group_size, last_group_start; 928 929 for (i = 0; i < rs->md.raid_disks; i++) 930 if (!test_bit(In_sync, &rs->dev[i].rdev.flags) || 931 !rs->dev[i].rdev.sb_page) 932 rebuild_cnt++; 933 934 switch (rs->raid_type->level) { 935 case 0: 936 break; 937 case 1: 938 if (rebuild_cnt >= rs->md.raid_disks) 939 goto too_many; 940 break; 941 case 4: 942 case 5: 943 case 6: 944 if (rebuild_cnt > rs->raid_type->parity_devs) 945 goto too_many; 946 break; 947 case 10: 948 copies = raid10_md_layout_to_copies(rs->md.new_layout); 949 if (rebuild_cnt < copies) 950 break; 951 952 /* 953 * It is possible to have a higher rebuild count for RAID10, 954 * as long as the failed devices occur in different mirror 955 * groups (i.e. different stripes). 956 * 957 * When checking "near" format, make sure no adjacent devices 958 * have failed beyond what can be handled. In addition to the 959 * simple case where the number of devices is a multiple of the 960 * number of copies, we must also handle cases where the number 961 * of devices is not a multiple of the number of copies. 962 * E.g. dev1 dev2 dev3 dev4 dev5 963 * A A B B C 964 * C D D E E 965 */ 966 if (__is_raid10_near(rs->md.new_layout)) { 967 for (i = 0; i < rs->md.raid_disks; i++) { 968 if (!(i % copies)) 969 rebuilds_per_group = 0; 970 if ((!rs->dev[i].rdev.sb_page || 971 !test_bit(In_sync, &rs->dev[i].rdev.flags)) && 972 (++rebuilds_per_group >= copies)) 973 goto too_many; 974 } 975 break; 976 } 977 978 /* 979 * When checking "far" and "offset" formats, we need to ensure 980 * that the device that holds its copy is not also dead or 981 * being rebuilt. (Note that "far" and "offset" formats only 982 * support two copies right now. These formats also only ever 983 * use the 'use_far_sets' variant.) 984 * 985 * This check is somewhat complicated by the need to account 986 * for arrays that are not a multiple of (far) copies. This 987 * results in the need to treat the last (potentially larger) 988 * set differently. 989 */ 990 group_size = (rs->md.raid_disks / copies); 991 last_group_start = (rs->md.raid_disks / group_size) - 1; 992 last_group_start *= group_size; 993 for (i = 0; i < rs->md.raid_disks; i++) { 994 if (!(i % copies) && !(i > last_group_start)) 995 rebuilds_per_group = 0; 996 if ((!rs->dev[i].rdev.sb_page || 997 !test_bit(In_sync, &rs->dev[i].rdev.flags)) && 998 (++rebuilds_per_group >= copies)) 999 goto too_many; 1000 } 1001 break; 1002 default: 1003 if (rebuild_cnt) 1004 return -EINVAL; 1005 } 1006 1007 return 0; 1008 1009 too_many: 1010 return -EINVAL; 1011 } 1012 1013 /* 1014 * Possible arguments are... 1015 * <chunk_size> [optional_args] 1016 * 1017 * Argument definitions 1018 * <chunk_size> The number of sectors per disk that 1019 * will form the "stripe" 1020 * [[no]sync] Force or prevent recovery of the 1021 * entire array 1022 * [rebuild <idx>] Rebuild the drive indicated by the index 1023 * [daemon_sleep <ms>] Time between bitmap daemon work to 1024 * clear bits 1025 * [min_recovery_rate <kB/sec/disk>] Throttle RAID initialization 1026 * [max_recovery_rate <kB/sec/disk>] Throttle RAID initialization 1027 * [write_mostly <idx>] Indicate a write mostly drive via index 1028 * [max_write_behind <sectors>] See '-write-behind=' (man mdadm) 1029 * [stripe_cache <sectors>] Stripe cache size for higher RAIDs 1030 * [region_size <sectors>] Defines granularity of bitmap 1031 * 1032 * RAID10-only options: 1033 * [raid10_copies <# copies>] Number of copies. (Default: 2) 1034 * [raid10_format <near|far|offset>] Layout algorithm. (Default: near) 1035 */ 1036 static int parse_raid_params(struct raid_set *rs, struct dm_arg_set *as, 1037 unsigned int num_raid_params) 1038 { 1039 int value, raid10_format = ALGORITHM_RAID10_DEFAULT; 1040 unsigned int raid10_copies = 2; 1041 unsigned int i, write_mostly = 0; 1042 unsigned int region_size = 0; 1043 sector_t max_io_len; 1044 const char *arg, *key; 1045 struct raid_dev *rd; 1046 struct raid_type *rt = rs->raid_type; 1047 1048 arg = dm_shift_arg(as); 1049 num_raid_params--; /* Account for chunk_size argument */ 1050 1051 if (kstrtoint(arg, 10, &value) < 0) { 1052 rs->ti->error = "Bad numerical argument given for chunk_size"; 1053 return -EINVAL; 1054 } 1055 1056 /* 1057 * First, parse the in-order required arguments 1058 * "chunk_size" is the only argument of this type. 1059 */ 1060 if (rt_is_raid1(rt)) { 1061 if (value) 1062 DMERR("Ignoring chunk size parameter for RAID 1"); 1063 value = 0; 1064 } else if (!is_power_of_2(value)) { 1065 rs->ti->error = "Chunk size must be a power of 2"; 1066 return -EINVAL; 1067 } else if (value < 8) { 1068 rs->ti->error = "Chunk size value is too small"; 1069 return -EINVAL; 1070 } 1071 1072 rs->md.new_chunk_sectors = rs->md.chunk_sectors = value; 1073 1074 /* 1075 * We set each individual device as In_sync with a completed 1076 * 'recovery_offset'. If there has been a device failure or 1077 * replacement then one of the following cases applies: 1078 * 1079 * 1) User specifies 'rebuild'. 1080 * - Device is reset when param is read. 1081 * 2) A new device is supplied. 1082 * - No matching superblock found, resets device. 1083 * 3) Device failure was transient and returns on reload. 1084 * - Failure noticed, resets device for bitmap replay. 1085 * 4) Device hadn't completed recovery after previous failure. 1086 * - Superblock is read and overrides recovery_offset. 1087 * 1088 * What is found in the superblocks of the devices is always 1089 * authoritative, unless 'rebuild' or '[no]sync' was specified. 1090 */ 1091 for (i = 0; i < rs->raid_disks; i++) { 1092 set_bit(In_sync, &rs->dev[i].rdev.flags); 1093 rs->dev[i].rdev.recovery_offset = MaxSector; 1094 } 1095 1096 /* 1097 * Second, parse the unordered optional arguments 1098 */ 1099 for (i = 0; i < num_raid_params; i++) { 1100 key = dm_shift_arg(as); 1101 if (!key) { 1102 rs->ti->error = "Not enough raid parameters given"; 1103 return -EINVAL; 1104 } 1105 1106 if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_NOSYNC))) { 1107 if (test_and_set_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) { 1108 rs->ti->error = "Only one 'nosync' argument allowed"; 1109 return -EINVAL; 1110 } 1111 continue; 1112 } 1113 if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_SYNC))) { 1114 if (test_and_set_bit(__CTR_FLAG_SYNC, &rs->ctr_flags)) { 1115 rs->ti->error = "Only one 'sync' argument allowed"; 1116 return -EINVAL; 1117 } 1118 continue; 1119 } 1120 if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_USE_NEAR_SETS))) { 1121 if (test_and_set_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags)) { 1122 rs->ti->error = "Only one 'raid10_use_new_sets' argument allowed"; 1123 return -EINVAL; 1124 } 1125 continue; 1126 } 1127 1128 arg = dm_shift_arg(as); 1129 i++; /* Account for the argument pairs */ 1130 if (!arg) { 1131 rs->ti->error = "Wrong number of raid parameters given"; 1132 return -EINVAL; 1133 } 1134 1135 /* 1136 * Parameters that take a string value are checked here. 1137 */ 1138 1139 if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_FORMAT))) { 1140 if (test_and_set_bit(__CTR_FLAG_RAID10_FORMAT, &rs->ctr_flags)) { 1141 rs->ti->error = "Only one 'raid10_format' argument pair allowed"; 1142 return -EINVAL; 1143 } 1144 if (!rt_is_raid10(rt)) { 1145 rs->ti->error = "'raid10_format' is an invalid parameter for this RAID type"; 1146 return -EINVAL; 1147 } 1148 raid10_format = raid10_name_to_format(arg); 1149 if (raid10_format < 0) { 1150 rs->ti->error = "Invalid 'raid10_format' value given"; 1151 return raid10_format; 1152 } 1153 continue; 1154 } 1155 1156 if (kstrtoint(arg, 10, &value) < 0) { 1157 rs->ti->error = "Bad numerical argument given in raid params"; 1158 return -EINVAL; 1159 } 1160 1161 if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_REBUILD))) { 1162 /* 1163 * "rebuild" is being passed in by userspace to provide 1164 * indexes of replaced devices and to set up additional 1165 * devices on raid level takeover. 1166 */ 1167 if (!__within_range(value, 0, rs->raid_disks - 1)) { 1168 rs->ti->error = "Invalid rebuild index given"; 1169 return -EINVAL; 1170 } 1171 1172 if (test_and_set_bit(value, (void *) rs->rebuild_disks)) { 1173 rs->ti->error = "rebuild for this index already given"; 1174 return -EINVAL; 1175 } 1176 1177 rd = rs->dev + value; 1178 clear_bit(In_sync, &rd->rdev.flags); 1179 clear_bit(Faulty, &rd->rdev.flags); 1180 rd->rdev.recovery_offset = 0; 1181 set_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags); 1182 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_WRITE_MOSTLY))) { 1183 if (!rt_is_raid1(rt)) { 1184 rs->ti->error = "write_mostly option is only valid for RAID1"; 1185 return -EINVAL; 1186 } 1187 1188 if (!__within_range(value, 0, rs->md.raid_disks - 1)) { 1189 rs->ti->error = "Invalid write_mostly index given"; 1190 return -EINVAL; 1191 } 1192 1193 write_mostly++; 1194 set_bit(WriteMostly, &rs->dev[value].rdev.flags); 1195 set_bit(__CTR_FLAG_WRITE_MOSTLY, &rs->ctr_flags); 1196 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MAX_WRITE_BEHIND))) { 1197 if (!rt_is_raid1(rt)) { 1198 rs->ti->error = "max_write_behind option is only valid for RAID1"; 1199 return -EINVAL; 1200 } 1201 1202 if (test_and_set_bit(__CTR_FLAG_MAX_WRITE_BEHIND, &rs->ctr_flags)) { 1203 rs->ti->error = "Only one max_write_behind argument pair allowed"; 1204 return -EINVAL; 1205 } 1206 1207 /* 1208 * In device-mapper, we specify things in sectors, but 1209 * MD records this value in kB 1210 */ 1211 value /= 2; 1212 if (value > COUNTER_MAX) { 1213 rs->ti->error = "Max write-behind limit out of range"; 1214 return -EINVAL; 1215 } 1216 1217 rs->md.bitmap_info.max_write_behind = value; 1218 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DAEMON_SLEEP))) { 1219 if (test_and_set_bit(__CTR_FLAG_DAEMON_SLEEP, &rs->ctr_flags)) { 1220 rs->ti->error = "Only one daemon_sleep argument pair allowed"; 1221 return -EINVAL; 1222 } 1223 if (!value || (value > MAX_SCHEDULE_TIMEOUT)) { 1224 rs->ti->error = "daemon sleep period out of range"; 1225 return -EINVAL; 1226 } 1227 rs->md.bitmap_info.daemon_sleep = value; 1228 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DATA_OFFSET))) { 1229 /* Userspace passes new data_offset after having extended the the data image LV */ 1230 if (test_and_set_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags)) { 1231 rs->ti->error = "Only one data_offset argument pair allowed"; 1232 return -EINVAL; 1233 } 1234 /* Ensure sensible data offset */ 1235 if (value < 0 || 1236 (value && (value < MIN_FREE_RESHAPE_SPACE || value % to_sector(PAGE_SIZE)))) { 1237 rs->ti->error = "Bogus data_offset value"; 1238 return -EINVAL; 1239 } 1240 rs->data_offset = value; 1241 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DELTA_DISKS))) { 1242 /* Define the +/-# of disks to add to/remove from the given raid set */ 1243 if (test_and_set_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags)) { 1244 rs->ti->error = "Only one delta_disks argument pair allowed"; 1245 return -EINVAL; 1246 } 1247 /* Ensure MAX_RAID_DEVICES and raid type minimal_devs! */ 1248 if (!__within_range(abs(value), 1, MAX_RAID_DEVICES - rt->minimal_devs)) { 1249 rs->ti->error = "Too many delta_disk requested"; 1250 return -EINVAL; 1251 } 1252 1253 rs->delta_disks = value; 1254 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_STRIPE_CACHE))) { 1255 if (test_and_set_bit(__CTR_FLAG_STRIPE_CACHE, &rs->ctr_flags)) { 1256 rs->ti->error = "Only one stripe_cache argument pair allowed"; 1257 return -EINVAL; 1258 } 1259 1260 if (!rt_is_raid456(rt)) { 1261 rs->ti->error = "Inappropriate argument: stripe_cache"; 1262 return -EINVAL; 1263 } 1264 1265 rs->stripe_cache_entries = value; 1266 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MIN_RECOVERY_RATE))) { 1267 if (test_and_set_bit(__CTR_FLAG_MIN_RECOVERY_RATE, &rs->ctr_flags)) { 1268 rs->ti->error = "Only one min_recovery_rate argument pair allowed"; 1269 return -EINVAL; 1270 } 1271 if (value > INT_MAX) { 1272 rs->ti->error = "min_recovery_rate out of range"; 1273 return -EINVAL; 1274 } 1275 rs->md.sync_speed_min = (int)value; 1276 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MAX_RECOVERY_RATE))) { 1277 if (test_and_set_bit(__CTR_FLAG_MAX_RECOVERY_RATE, &rs->ctr_flags)) { 1278 rs->ti->error = "Only one max_recovery_rate argument pair allowed"; 1279 return -EINVAL; 1280 } 1281 if (value > INT_MAX) { 1282 rs->ti->error = "max_recovery_rate out of range"; 1283 return -EINVAL; 1284 } 1285 rs->md.sync_speed_max = (int)value; 1286 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_REGION_SIZE))) { 1287 if (test_and_set_bit(__CTR_FLAG_REGION_SIZE, &rs->ctr_flags)) { 1288 rs->ti->error = "Only one region_size argument pair allowed"; 1289 return -EINVAL; 1290 } 1291 1292 region_size = value; 1293 rs->requested_bitmap_chunk_sectors = value; 1294 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_COPIES))) { 1295 if (test_and_set_bit(__CTR_FLAG_RAID10_COPIES, &rs->ctr_flags)) { 1296 rs->ti->error = "Only one raid10_copies argument pair allowed"; 1297 return -EINVAL; 1298 } 1299 1300 if (!__within_range(value, 2, rs->md.raid_disks)) { 1301 rs->ti->error = "Bad value for 'raid10_copies'"; 1302 return -EINVAL; 1303 } 1304 1305 raid10_copies = value; 1306 } else { 1307 DMERR("Unable to parse RAID parameter: %s", key); 1308 rs->ti->error = "Unable to parse RAID parameter"; 1309 return -EINVAL; 1310 } 1311 } 1312 1313 if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags) && 1314 test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) { 1315 rs->ti->error = "sync and nosync are mutually exclusive"; 1316 return -EINVAL; 1317 } 1318 1319 if (test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags) && 1320 (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags) || 1321 test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags))) { 1322 rs->ti->error = "sync/nosync and rebuild are mutually exclusive"; 1323 return -EINVAL; 1324 } 1325 1326 if (write_mostly >= rs->md.raid_disks) { 1327 rs->ti->error = "Can't set all raid1 devices to write_mostly"; 1328 return -EINVAL; 1329 } 1330 1331 if (validate_region_size(rs, region_size)) 1332 return -EINVAL; 1333 1334 if (rs->md.chunk_sectors) 1335 max_io_len = rs->md.chunk_sectors; 1336 else 1337 max_io_len = region_size; 1338 1339 if (dm_set_target_max_io_len(rs->ti, max_io_len)) 1340 return -EINVAL; 1341 1342 if (rt_is_raid10(rt)) { 1343 if (raid10_copies > rs->md.raid_disks) { 1344 rs->ti->error = "Not enough devices to satisfy specification"; 1345 return -EINVAL; 1346 } 1347 1348 rs->md.new_layout = raid10_format_to_md_layout(rs, raid10_format, raid10_copies); 1349 if (rs->md.new_layout < 0) { 1350 rs->ti->error = "Error getting raid10 format"; 1351 return rs->md.new_layout; 1352 } 1353 1354 rt = get_raid_type_by_ll(10, rs->md.new_layout); 1355 if (!rt) { 1356 rs->ti->error = "Failed to recognize new raid10 layout"; 1357 return -EINVAL; 1358 } 1359 1360 if ((rt->algorithm == ALGORITHM_RAID10_DEFAULT || 1361 rt->algorithm == ALGORITHM_RAID10_NEAR) && 1362 test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags)) { 1363 rs->ti->error = "RAID10 format 'near' and 'raid10_use_near_sets' are incompatible"; 1364 return -EINVAL; 1365 } 1366 } 1367 1368 rs->raid10_copies = raid10_copies; 1369 1370 /* Assume there are no metadata devices until the drives are parsed */ 1371 rs->md.persistent = 0; 1372 rs->md.external = 1; 1373 1374 /* Check, if any invalid ctr arguments have been passed in for the raid level */ 1375 return rs_check_for_valid_flags(rs); 1376 } 1377 1378 /* Set raid4/5/6 cache size */ 1379 static int rs_set_raid456_stripe_cache(struct raid_set *rs) 1380 { 1381 int r; 1382 struct r5conf *conf; 1383 struct mddev *mddev = &rs->md; 1384 uint32_t min_stripes = max(mddev->chunk_sectors, mddev->new_chunk_sectors) / 2; 1385 uint32_t nr_stripes = rs->stripe_cache_entries; 1386 1387 if (!rt_is_raid456(rs->raid_type)) { 1388 rs->ti->error = "Inappropriate raid level; cannot change stripe_cache size"; 1389 return -EINVAL; 1390 } 1391 1392 if (nr_stripes < min_stripes) { 1393 DMINFO("Adjusting requested %u stripe cache entries to %u to suit stripe size", 1394 nr_stripes, min_stripes); 1395 nr_stripes = min_stripes; 1396 } 1397 1398 conf = mddev->private; 1399 if (!conf) { 1400 rs->ti->error = "Cannot change stripe_cache size on inactive RAID set"; 1401 return -EINVAL; 1402 } 1403 1404 /* Try setting number of stripes in raid456 stripe cache */ 1405 if (conf->min_nr_stripes != nr_stripes) { 1406 r = raid5_set_cache_size(mddev, nr_stripes); 1407 if (r) { 1408 rs->ti->error = "Failed to set raid4/5/6 stripe cache size"; 1409 return r; 1410 } 1411 1412 DMINFO("%u stripe cache entries", nr_stripes); 1413 } 1414 1415 return 0; 1416 } 1417 1418 /* Return # of data stripes as kept in mddev as of @rs (i.e. as of superblock) */ 1419 static unsigned int mddev_data_stripes(struct raid_set *rs) 1420 { 1421 return rs->md.raid_disks - rs->raid_type->parity_devs; 1422 } 1423 1424 /* Return # of data stripes of @rs (i.e. as of ctr) */ 1425 static unsigned int rs_data_stripes(struct raid_set *rs) 1426 { 1427 return rs->raid_disks - rs->raid_type->parity_devs; 1428 } 1429 1430 /* Calculate the sectors per device and per array used for @rs */ 1431 static int rs_set_dev_and_array_sectors(struct raid_set *rs, bool use_mddev) 1432 { 1433 int delta_disks; 1434 unsigned int data_stripes; 1435 struct mddev *mddev = &rs->md; 1436 struct md_rdev *rdev; 1437 sector_t array_sectors = rs->ti->len, dev_sectors = rs->ti->len; 1438 1439 if (use_mddev) { 1440 delta_disks = mddev->delta_disks; 1441 data_stripes = mddev_data_stripes(rs); 1442 } else { 1443 delta_disks = rs->delta_disks; 1444 data_stripes = rs_data_stripes(rs); 1445 } 1446 1447 /* Special raid1 case w/o delta_disks support (yet) */ 1448 if (rt_is_raid1(rs->raid_type)) 1449 ; 1450 else if (rt_is_raid10(rs->raid_type)) { 1451 if (rs->raid10_copies < 2 || 1452 delta_disks < 0) { 1453 rs->ti->error = "Bogus raid10 data copies or delta disks"; 1454 return -EINVAL; 1455 } 1456 1457 dev_sectors *= rs->raid10_copies; 1458 if (sector_div(dev_sectors, data_stripes)) 1459 goto bad; 1460 1461 array_sectors = (data_stripes + delta_disks) * dev_sectors; 1462 if (sector_div(array_sectors, rs->raid10_copies)) 1463 goto bad; 1464 1465 } else if (sector_div(dev_sectors, data_stripes)) 1466 goto bad; 1467 1468 else 1469 /* Striped layouts */ 1470 array_sectors = (data_stripes + delta_disks) * dev_sectors; 1471 1472 rdev_for_each(rdev, mddev) 1473 rdev->sectors = dev_sectors; 1474 1475 mddev->array_sectors = array_sectors; 1476 mddev->dev_sectors = dev_sectors; 1477 1478 return 0; 1479 bad: 1480 rs->ti->error = "Target length not divisible by number of data devices"; 1481 return -EINVAL; 1482 } 1483 1484 /* Setup recovery on @rs */ 1485 static void __rs_setup_recovery(struct raid_set *rs, sector_t dev_sectors) 1486 { 1487 /* raid0 does not recover */ 1488 if (rs_is_raid0(rs)) 1489 rs->md.recovery_cp = MaxSector; 1490 /* 1491 * A raid6 set has to be recovered either 1492 * completely or for the grown part to 1493 * ensure proper parity and Q-Syndrome 1494 */ 1495 else if (rs_is_raid6(rs)) 1496 rs->md.recovery_cp = dev_sectors; 1497 /* 1498 * Other raid set types may skip recovery 1499 * depending on the 'nosync' flag. 1500 */ 1501 else 1502 rs->md.recovery_cp = test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags) 1503 ? MaxSector : dev_sectors; 1504 } 1505 1506 /* Setup recovery on @rs based on raid type, device size and 'nosync' flag */ 1507 static void rs_setup_recovery(struct raid_set *rs, sector_t dev_sectors) 1508 { 1509 if (!dev_sectors) 1510 /* New raid set or 'sync' flag provided */ 1511 __rs_setup_recovery(rs, 0); 1512 else if (dev_sectors == MaxSector) 1513 /* Prevent recovery */ 1514 __rs_setup_recovery(rs, MaxSector); 1515 else if (rs->dev[0].rdev.sectors < dev_sectors) 1516 /* Grown raid set */ 1517 __rs_setup_recovery(rs, rs->dev[0].rdev.sectors); 1518 else 1519 __rs_setup_recovery(rs, MaxSector); 1520 } 1521 1522 static void do_table_event(struct work_struct *ws) 1523 { 1524 struct raid_set *rs = container_of(ws, struct raid_set, md.event_work); 1525 1526 smp_rmb(); /* Make sure we access most actual mddev properties */ 1527 if (!rs_is_reshaping(rs)) 1528 rs_set_capacity(rs); 1529 dm_table_event(rs->ti->table); 1530 } 1531 1532 static int raid_is_congested(struct dm_target_callbacks *cb, int bits) 1533 { 1534 struct raid_set *rs = container_of(cb, struct raid_set, callbacks); 1535 1536 return mddev_congested(&rs->md, bits); 1537 } 1538 1539 /* 1540 * Make sure a valid takover (level switch) is being requested on @rs 1541 * 1542 * Conversions of raid sets from one MD personality to another 1543 * have to conform to restrictions which are enforced here. 1544 */ 1545 static int rs_check_takeover(struct raid_set *rs) 1546 { 1547 struct mddev *mddev = &rs->md; 1548 unsigned int near_copies; 1549 1550 if (rs->md.degraded) { 1551 rs->ti->error = "Can't takeover degraded raid set"; 1552 return -EPERM; 1553 } 1554 1555 if (rs_is_reshaping(rs)) { 1556 rs->ti->error = "Can't takeover reshaping raid set"; 1557 return -EPERM; 1558 } 1559 1560 switch (mddev->level) { 1561 case 0: 1562 /* raid0 -> raid1/5 with one disk */ 1563 if ((mddev->new_level == 1 || mddev->new_level == 5) && 1564 mddev->raid_disks == 1) 1565 return 0; 1566 1567 /* raid0 -> raid10 */ 1568 if (mddev->new_level == 10 && 1569 !(rs->raid_disks % mddev->raid_disks)) 1570 return 0; 1571 1572 /* raid0 with multiple disks -> raid4/5/6 */ 1573 if (__within_range(mddev->new_level, 4, 6) && 1574 mddev->new_layout == ALGORITHM_PARITY_N && 1575 mddev->raid_disks > 1) 1576 return 0; 1577 1578 break; 1579 1580 case 10: 1581 /* Can't takeover raid10_offset! */ 1582 if (__is_raid10_offset(mddev->layout)) 1583 break; 1584 1585 near_copies = __raid10_near_copies(mddev->layout); 1586 1587 /* raid10* -> raid0 */ 1588 if (mddev->new_level == 0) { 1589 /* Can takeover raid10_near with raid disks divisable by data copies! */ 1590 if (near_copies > 1 && 1591 !(mddev->raid_disks % near_copies)) { 1592 mddev->raid_disks /= near_copies; 1593 mddev->delta_disks = mddev->raid_disks; 1594 return 0; 1595 } 1596 1597 /* Can takeover raid10_far */ 1598 if (near_copies == 1 && 1599 __raid10_far_copies(mddev->layout) > 1) 1600 return 0; 1601 1602 break; 1603 } 1604 1605 /* raid10_{near,far} -> raid1 */ 1606 if (mddev->new_level == 1 && 1607 max(near_copies, __raid10_far_copies(mddev->layout)) == mddev->raid_disks) 1608 return 0; 1609 1610 /* raid10_{near,far} with 2 disks -> raid4/5 */ 1611 if (__within_range(mddev->new_level, 4, 5) && 1612 mddev->raid_disks == 2) 1613 return 0; 1614 break; 1615 1616 case 1: 1617 /* raid1 with 2 disks -> raid4/5 */ 1618 if (__within_range(mddev->new_level, 4, 5) && 1619 mddev->raid_disks == 2) { 1620 mddev->degraded = 1; 1621 return 0; 1622 } 1623 1624 /* raid1 -> raid0 */ 1625 if (mddev->new_level == 0 && 1626 mddev->raid_disks == 1) 1627 return 0; 1628 1629 /* raid1 -> raid10 */ 1630 if (mddev->new_level == 10) 1631 return 0; 1632 break; 1633 1634 case 4: 1635 /* raid4 -> raid0 */ 1636 if (mddev->new_level == 0) 1637 return 0; 1638 1639 /* raid4 -> raid1/5 with 2 disks */ 1640 if ((mddev->new_level == 1 || mddev->new_level == 5) && 1641 mddev->raid_disks == 2) 1642 return 0; 1643 1644 /* raid4 -> raid5/6 with parity N */ 1645 if (__within_range(mddev->new_level, 5, 6) && 1646 mddev->layout == ALGORITHM_PARITY_N) 1647 return 0; 1648 break; 1649 1650 case 5: 1651 /* raid5 with parity N -> raid0 */ 1652 if (mddev->new_level == 0 && 1653 mddev->layout == ALGORITHM_PARITY_N) 1654 return 0; 1655 1656 /* raid5 with parity N -> raid4 */ 1657 if (mddev->new_level == 4 && 1658 mddev->layout == ALGORITHM_PARITY_N) 1659 return 0; 1660 1661 /* raid5 with 2 disks -> raid1/4/10 */ 1662 if ((mddev->new_level == 1 || mddev->new_level == 4 || mddev->new_level == 10) && 1663 mddev->raid_disks == 2) 1664 return 0; 1665 1666 /* raid5_* -> raid6_*_6 with Q-Syndrome N (e.g. raid5_ra -> raid6_ra_6 */ 1667 if (mddev->new_level == 6 && 1668 ((mddev->layout == ALGORITHM_PARITY_N && mddev->new_layout == ALGORITHM_PARITY_N) || 1669 __within_range(mddev->new_layout, ALGORITHM_LEFT_ASYMMETRIC_6, ALGORITHM_RIGHT_SYMMETRIC_6))) 1670 return 0; 1671 break; 1672 1673 case 6: 1674 /* raid6 with parity N -> raid0 */ 1675 if (mddev->new_level == 0 && 1676 mddev->layout == ALGORITHM_PARITY_N) 1677 return 0; 1678 1679 /* raid6 with parity N -> raid4 */ 1680 if (mddev->new_level == 4 && 1681 mddev->layout == ALGORITHM_PARITY_N) 1682 return 0; 1683 1684 /* raid6_*_n with Q-Syndrome N -> raid5_* */ 1685 if (mddev->new_level == 5 && 1686 ((mddev->layout == ALGORITHM_PARITY_N && mddev->new_layout == ALGORITHM_PARITY_N) || 1687 __within_range(mddev->new_layout, ALGORITHM_LEFT_ASYMMETRIC, ALGORITHM_RIGHT_SYMMETRIC))) 1688 return 0; 1689 1690 default: 1691 break; 1692 } 1693 1694 rs->ti->error = "takeover not possible"; 1695 return -EINVAL; 1696 } 1697 1698 /* True if @rs requested to be taken over */ 1699 static bool rs_takeover_requested(struct raid_set *rs) 1700 { 1701 return rs->md.new_level != rs->md.level; 1702 } 1703 1704 /* True if @rs is requested to reshape by ctr */ 1705 static bool rs_reshape_requested(struct raid_set *rs) 1706 { 1707 bool change; 1708 struct mddev *mddev = &rs->md; 1709 1710 if (rs_takeover_requested(rs)) 1711 return false; 1712 1713 if (!mddev->level) 1714 return false; 1715 1716 change = mddev->new_layout != mddev->layout || 1717 mddev->new_chunk_sectors != mddev->chunk_sectors || 1718 rs->delta_disks; 1719 1720 /* Historical case to support raid1 reshape without delta disks */ 1721 if (mddev->level == 1) { 1722 if (rs->delta_disks) 1723 return !!rs->delta_disks; 1724 1725 return !change && 1726 mddev->raid_disks != rs->raid_disks; 1727 } 1728 1729 if (mddev->level == 10) 1730 return change && 1731 !__is_raid10_far(mddev->new_layout) && 1732 rs->delta_disks >= 0; 1733 1734 return change; 1735 } 1736 1737 /* Features */ 1738 #define FEATURE_FLAG_SUPPORTS_V190 0x1 /* Supports extended superblock */ 1739 1740 /* State flags for sb->flags */ 1741 #define SB_FLAG_RESHAPE_ACTIVE 0x1 1742 #define SB_FLAG_RESHAPE_BACKWARDS 0x2 1743 1744 /* 1745 * This structure is never routinely used by userspace, unlike md superblocks. 1746 * Devices with this superblock should only ever be accessed via device-mapper. 1747 */ 1748 #define DM_RAID_MAGIC 0x64526D44 1749 struct dm_raid_superblock { 1750 __le32 magic; /* "DmRd" */ 1751 __le32 compat_features; /* Used to indicate compatible features (like 1.9.0 ondisk metadata extension) */ 1752 1753 __le32 num_devices; /* Number of devices in this raid set. (Max 64) */ 1754 __le32 array_position; /* The position of this drive in the raid set */ 1755 1756 __le64 events; /* Incremented by md when superblock updated */ 1757 __le64 failed_devices; /* Pre 1.9.0 part of bit field of devices to */ 1758 /* indicate failures (see extension below) */ 1759 1760 /* 1761 * This offset tracks the progress of the repair or replacement of 1762 * an individual drive. 1763 */ 1764 __le64 disk_recovery_offset; 1765 1766 /* 1767 * This offset tracks the progress of the initial raid set 1768 * synchronisation/parity calculation. 1769 */ 1770 __le64 array_resync_offset; 1771 1772 /* 1773 * raid characteristics 1774 */ 1775 __le32 level; 1776 __le32 layout; 1777 __le32 stripe_sectors; 1778 1779 /******************************************************************** 1780 * BELOW FOLLOW V1.9.0 EXTENSIONS TO THE PRISTINE SUPERBLOCK FORMAT!!! 1781 * 1782 * FEATURE_FLAG_SUPPORTS_V190 in the features member indicates that those exist 1783 */ 1784 1785 __le32 flags; /* Flags defining array states for reshaping */ 1786 1787 /* 1788 * This offset tracks the progress of a raid 1789 * set reshape in order to be able to restart it 1790 */ 1791 __le64 reshape_position; 1792 1793 /* 1794 * These define the properties of the array in case of an interrupted reshape 1795 */ 1796 __le32 new_level; 1797 __le32 new_layout; 1798 __le32 new_stripe_sectors; 1799 __le32 delta_disks; 1800 1801 __le64 array_sectors; /* Array size in sectors */ 1802 1803 /* 1804 * Sector offsets to data on devices (reshaping). 1805 * Needed to support out of place reshaping, thus 1806 * not writing over any stripes whilst converting 1807 * them from old to new layout 1808 */ 1809 __le64 data_offset; 1810 __le64 new_data_offset; 1811 1812 __le64 sectors; /* Used device size in sectors */ 1813 1814 /* 1815 * Additonal Bit field of devices indicating failures to support 1816 * up to 256 devices with the 1.9.0 on-disk metadata format 1817 */ 1818 __le64 extended_failed_devices[DISKS_ARRAY_ELEMS - 1]; 1819 1820 __le32 incompat_features; /* Used to indicate any incompatible features */ 1821 1822 /* Always set rest up to logical block size to 0 when writing (see get_metadata_device() below). */ 1823 } __packed; 1824 1825 /* 1826 * Check for reshape constraints on raid set @rs: 1827 * 1828 * - reshape function non-existent 1829 * - degraded set 1830 * - ongoing recovery 1831 * - ongoing reshape 1832 * 1833 * Returns 0 if none or -EPERM if given constraint 1834 * and error message reference in @errmsg 1835 */ 1836 static int rs_check_reshape(struct raid_set *rs) 1837 { 1838 struct mddev *mddev = &rs->md; 1839 1840 if (!mddev->pers || !mddev->pers->check_reshape) 1841 rs->ti->error = "Reshape not supported"; 1842 else if (mddev->degraded) 1843 rs->ti->error = "Can't reshape degraded raid set"; 1844 else if (rs_is_recovering(rs)) 1845 rs->ti->error = "Convert request on recovering raid set prohibited"; 1846 else if (rs_is_reshaping(rs)) 1847 rs->ti->error = "raid set already reshaping!"; 1848 else if (!(rs_is_raid1(rs) || rs_is_raid10(rs) || rs_is_raid456(rs))) 1849 rs->ti->error = "Reshaping only supported for raid1/4/5/6/10"; 1850 else 1851 return 0; 1852 1853 return -EPERM; 1854 } 1855 1856 static int read_disk_sb(struct md_rdev *rdev, int size) 1857 { 1858 BUG_ON(!rdev->sb_page); 1859 1860 if (rdev->sb_loaded) 1861 return 0; 1862 1863 if (!sync_page_io(rdev, 0, size, rdev->sb_page, REQ_OP_READ, 0, true)) { 1864 DMERR("Failed to read superblock of device at position %d", 1865 rdev->raid_disk); 1866 md_error(rdev->mddev, rdev); 1867 return -EINVAL; 1868 } 1869 1870 rdev->sb_loaded = 1; 1871 1872 return 0; 1873 } 1874 1875 static void sb_retrieve_failed_devices(struct dm_raid_superblock *sb, uint64_t *failed_devices) 1876 { 1877 failed_devices[0] = le64_to_cpu(sb->failed_devices); 1878 memset(failed_devices + 1, 0, sizeof(sb->extended_failed_devices)); 1879 1880 if (le32_to_cpu(sb->compat_features) & FEATURE_FLAG_SUPPORTS_V190) { 1881 int i = ARRAY_SIZE(sb->extended_failed_devices); 1882 1883 while (i--) 1884 failed_devices[i+1] = le64_to_cpu(sb->extended_failed_devices[i]); 1885 } 1886 } 1887 1888 static void sb_update_failed_devices(struct dm_raid_superblock *sb, uint64_t *failed_devices) 1889 { 1890 int i = ARRAY_SIZE(sb->extended_failed_devices); 1891 1892 sb->failed_devices = cpu_to_le64(failed_devices[0]); 1893 while (i--) 1894 sb->extended_failed_devices[i] = cpu_to_le64(failed_devices[i+1]); 1895 } 1896 1897 /* 1898 * Synchronize the superblock members with the raid set properties 1899 * 1900 * All superblock data is little endian. 1901 */ 1902 static void super_sync(struct mddev *mddev, struct md_rdev *rdev) 1903 { 1904 bool update_failed_devices = false; 1905 unsigned int i; 1906 uint64_t failed_devices[DISKS_ARRAY_ELEMS]; 1907 struct dm_raid_superblock *sb; 1908 struct raid_set *rs = container_of(mddev, struct raid_set, md); 1909 1910 /* No metadata device, no superblock */ 1911 if (!rdev->meta_bdev) 1912 return; 1913 1914 BUG_ON(!rdev->sb_page); 1915 1916 sb = page_address(rdev->sb_page); 1917 1918 sb_retrieve_failed_devices(sb, failed_devices); 1919 1920 for (i = 0; i < rs->raid_disks; i++) 1921 if (!rs->dev[i].data_dev || test_bit(Faulty, &rs->dev[i].rdev.flags)) { 1922 update_failed_devices = true; 1923 set_bit(i, (void *) failed_devices); 1924 } 1925 1926 if (update_failed_devices) 1927 sb_update_failed_devices(sb, failed_devices); 1928 1929 sb->magic = cpu_to_le32(DM_RAID_MAGIC); 1930 sb->compat_features = cpu_to_le32(FEATURE_FLAG_SUPPORTS_V190); 1931 1932 sb->num_devices = cpu_to_le32(mddev->raid_disks); 1933 sb->array_position = cpu_to_le32(rdev->raid_disk); 1934 1935 sb->events = cpu_to_le64(mddev->events); 1936 1937 sb->disk_recovery_offset = cpu_to_le64(rdev->recovery_offset); 1938 sb->array_resync_offset = cpu_to_le64(mddev->recovery_cp); 1939 1940 sb->level = cpu_to_le32(mddev->level); 1941 sb->layout = cpu_to_le32(mddev->layout); 1942 sb->stripe_sectors = cpu_to_le32(mddev->chunk_sectors); 1943 1944 sb->new_level = cpu_to_le32(mddev->new_level); 1945 sb->new_layout = cpu_to_le32(mddev->new_layout); 1946 sb->new_stripe_sectors = cpu_to_le32(mddev->new_chunk_sectors); 1947 1948 sb->delta_disks = cpu_to_le32(mddev->delta_disks); 1949 1950 smp_rmb(); /* Make sure we access most recent reshape position */ 1951 sb->reshape_position = cpu_to_le64(mddev->reshape_position); 1952 if (le64_to_cpu(sb->reshape_position) != MaxSector) { 1953 /* Flag ongoing reshape */ 1954 sb->flags |= cpu_to_le32(SB_FLAG_RESHAPE_ACTIVE); 1955 1956 if (mddev->delta_disks < 0 || mddev->reshape_backwards) 1957 sb->flags |= cpu_to_le32(SB_FLAG_RESHAPE_BACKWARDS); 1958 } else { 1959 /* Clear reshape flags */ 1960 sb->flags &= ~(cpu_to_le32(SB_FLAG_RESHAPE_ACTIVE|SB_FLAG_RESHAPE_BACKWARDS)); 1961 } 1962 1963 sb->array_sectors = cpu_to_le64(mddev->array_sectors); 1964 sb->data_offset = cpu_to_le64(rdev->data_offset); 1965 sb->new_data_offset = cpu_to_le64(rdev->new_data_offset); 1966 sb->sectors = cpu_to_le64(rdev->sectors); 1967 sb->incompat_features = cpu_to_le32(0); 1968 1969 /* Zero out the rest of the payload after the size of the superblock */ 1970 memset(sb + 1, 0, rdev->sb_size - sizeof(*sb)); 1971 } 1972 1973 /* 1974 * super_load 1975 * 1976 * This function creates a superblock if one is not found on the device 1977 * and will decide which superblock to use if there's a choice. 1978 * 1979 * Return: 1 if use rdev, 0 if use refdev, -Exxx otherwise 1980 */ 1981 static int super_load(struct md_rdev *rdev, struct md_rdev *refdev) 1982 { 1983 int r; 1984 struct dm_raid_superblock *sb; 1985 struct dm_raid_superblock *refsb; 1986 uint64_t events_sb, events_refsb; 1987 1988 rdev->sb_start = 0; 1989 rdev->sb_size = bdev_logical_block_size(rdev->meta_bdev); 1990 if (rdev->sb_size < sizeof(*sb) || rdev->sb_size > PAGE_SIZE) { 1991 DMERR("superblock size of a logical block is no longer valid"); 1992 return -EINVAL; 1993 } 1994 1995 r = read_disk_sb(rdev, rdev->sb_size); 1996 if (r) 1997 return r; 1998 1999 sb = page_address(rdev->sb_page); 2000 2001 /* 2002 * Two cases that we want to write new superblocks and rebuild: 2003 * 1) New device (no matching magic number) 2004 * 2) Device specified for rebuild (!In_sync w/ offset == 0) 2005 */ 2006 if ((sb->magic != cpu_to_le32(DM_RAID_MAGIC)) || 2007 (!test_bit(In_sync, &rdev->flags) && !rdev->recovery_offset)) { 2008 super_sync(rdev->mddev, rdev); 2009 2010 set_bit(FirstUse, &rdev->flags); 2011 sb->compat_features = cpu_to_le32(FEATURE_FLAG_SUPPORTS_V190); 2012 2013 /* Force writing of superblocks to disk */ 2014 set_bit(MD_CHANGE_DEVS, &rdev->mddev->flags); 2015 2016 /* Any superblock is better than none, choose that if given */ 2017 return refdev ? 0 : 1; 2018 } 2019 2020 if (!refdev) 2021 return 1; 2022 2023 events_sb = le64_to_cpu(sb->events); 2024 2025 refsb = page_address(refdev->sb_page); 2026 events_refsb = le64_to_cpu(refsb->events); 2027 2028 return (events_sb > events_refsb) ? 1 : 0; 2029 } 2030 2031 static int super_init_validation(struct raid_set *rs, struct md_rdev *rdev) 2032 { 2033 int role; 2034 unsigned int d; 2035 struct mddev *mddev = &rs->md; 2036 uint64_t events_sb; 2037 uint64_t failed_devices[DISKS_ARRAY_ELEMS]; 2038 struct dm_raid_superblock *sb; 2039 uint32_t new_devs = 0, rebuild_and_new = 0, rebuilds = 0; 2040 struct md_rdev *r; 2041 struct dm_raid_superblock *sb2; 2042 2043 sb = page_address(rdev->sb_page); 2044 events_sb = le64_to_cpu(sb->events); 2045 2046 /* 2047 * Initialise to 1 if this is a new superblock. 2048 */ 2049 mddev->events = events_sb ? : 1; 2050 2051 mddev->reshape_position = MaxSector; 2052 2053 /* 2054 * Reshaping is supported, e.g. reshape_position is valid 2055 * in superblock and superblock content is authoritative. 2056 */ 2057 if (le32_to_cpu(sb->compat_features) & FEATURE_FLAG_SUPPORTS_V190) { 2058 /* Superblock is authoritative wrt given raid set layout! */ 2059 mddev->raid_disks = le32_to_cpu(sb->num_devices); 2060 mddev->level = le32_to_cpu(sb->level); 2061 mddev->layout = le32_to_cpu(sb->layout); 2062 mddev->chunk_sectors = le32_to_cpu(sb->stripe_sectors); 2063 mddev->new_level = le32_to_cpu(sb->new_level); 2064 mddev->new_layout = le32_to_cpu(sb->new_layout); 2065 mddev->new_chunk_sectors = le32_to_cpu(sb->new_stripe_sectors); 2066 mddev->delta_disks = le32_to_cpu(sb->delta_disks); 2067 mddev->array_sectors = le64_to_cpu(sb->array_sectors); 2068 2069 /* raid was reshaping and got interrupted */ 2070 if (le32_to_cpu(sb->flags) & SB_FLAG_RESHAPE_ACTIVE) { 2071 if (test_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags)) { 2072 DMERR("Reshape requested but raid set is still reshaping"); 2073 return -EINVAL; 2074 } 2075 2076 if (mddev->delta_disks < 0 || 2077 (!mddev->delta_disks && (le32_to_cpu(sb->flags) & SB_FLAG_RESHAPE_BACKWARDS))) 2078 mddev->reshape_backwards = 1; 2079 else 2080 mddev->reshape_backwards = 0; 2081 2082 mddev->reshape_position = le64_to_cpu(sb->reshape_position); 2083 rs->raid_type = get_raid_type_by_ll(mddev->level, mddev->layout); 2084 } 2085 2086 } else { 2087 /* 2088 * No takeover/reshaping, because we don't have the extended v1.9.0 metadata 2089 */ 2090 if (le32_to_cpu(sb->level) != mddev->level) { 2091 DMERR("Reshaping/takeover raid sets not yet supported. (raid level/stripes/size change)"); 2092 return -EINVAL; 2093 } 2094 if (le32_to_cpu(sb->layout) != mddev->layout) { 2095 DMERR("Reshaping raid sets not yet supported. (raid layout change)"); 2096 DMERR(" 0x%X vs 0x%X", le32_to_cpu(sb->layout), mddev->layout); 2097 DMERR(" Old layout: %s w/ %d copies", 2098 raid10_md_layout_to_format(le32_to_cpu(sb->layout)), 2099 raid10_md_layout_to_copies(le32_to_cpu(sb->layout))); 2100 DMERR(" New layout: %s w/ %d copies", 2101 raid10_md_layout_to_format(mddev->layout), 2102 raid10_md_layout_to_copies(mddev->layout)); 2103 return -EINVAL; 2104 } 2105 if (le32_to_cpu(sb->stripe_sectors) != mddev->chunk_sectors) { 2106 DMERR("Reshaping raid sets not yet supported. (stripe sectors change)"); 2107 return -EINVAL; 2108 } 2109 2110 /* We can only change the number of devices in raid1 with old (i.e. pre 1.0.7) metadata */ 2111 if (!rt_is_raid1(rs->raid_type) && 2112 (le32_to_cpu(sb->num_devices) != mddev->raid_disks)) { 2113 DMERR("Reshaping raid sets not yet supported. (device count change from %u to %u)", 2114 sb->num_devices, mddev->raid_disks); 2115 return -EINVAL; 2116 } 2117 2118 /* Table line is checked vs. authoritative superblock */ 2119 rs_set_new(rs); 2120 } 2121 2122 if (!test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) 2123 mddev->recovery_cp = le64_to_cpu(sb->array_resync_offset); 2124 2125 /* 2126 * During load, we set FirstUse if a new superblock was written. 2127 * There are two reasons we might not have a superblock: 2128 * 1) The raid set is brand new - in which case, all of the 2129 * devices must have their In_sync bit set. Also, 2130 * recovery_cp must be 0, unless forced. 2131 * 2) This is a new device being added to an old raid set 2132 * and the new device needs to be rebuilt - in which 2133 * case the In_sync bit will /not/ be set and 2134 * recovery_cp must be MaxSector. 2135 * 3) This is/are a new device(s) being added to an old 2136 * raid set during takeover to a higher raid level 2137 * to provide capacity for redundancy or during reshape 2138 * to add capacity to grow the raid set. 2139 */ 2140 d = 0; 2141 rdev_for_each(r, mddev) { 2142 if (test_bit(FirstUse, &r->flags)) 2143 new_devs++; 2144 2145 if (!test_bit(In_sync, &r->flags)) { 2146 DMINFO("Device %d specified for rebuild; clearing superblock", 2147 r->raid_disk); 2148 rebuilds++; 2149 2150 if (test_bit(FirstUse, &r->flags)) 2151 rebuild_and_new++; 2152 } 2153 2154 d++; 2155 } 2156 2157 if (new_devs == rs->raid_disks || !rebuilds) { 2158 /* Replace a broken device */ 2159 if (new_devs == 1 && !rs->delta_disks) 2160 ; 2161 if (new_devs == rs->raid_disks) { 2162 DMINFO("Superblocks created for new raid set"); 2163 set_bit(MD_ARRAY_FIRST_USE, &mddev->flags); 2164 } else if (new_devs != rebuilds && 2165 new_devs != rs->delta_disks) { 2166 DMERR("New device injected into existing raid set without " 2167 "'delta_disks' or 'rebuild' parameter specified"); 2168 return -EINVAL; 2169 } 2170 } else if (new_devs && new_devs != rebuilds) { 2171 DMERR("%u 'rebuild' devices cannot be injected into" 2172 " a raid set with %u other first-time devices", 2173 rebuilds, new_devs); 2174 return -EINVAL; 2175 } else if (rebuilds) { 2176 if (rebuild_and_new && rebuilds != rebuild_and_new) { 2177 DMERR("new device%s provided without 'rebuild'", 2178 new_devs > 1 ? "s" : ""); 2179 return -EINVAL; 2180 } else if (rs_is_recovering(rs)) { 2181 DMERR("'rebuild' specified while raid set is not in-sync (recovery_cp=%llu)", 2182 (unsigned long long) mddev->recovery_cp); 2183 return -EINVAL; 2184 } else if (rs_is_reshaping(rs)) { 2185 DMERR("'rebuild' specified while raid set is being reshaped (reshape_position=%llu)", 2186 (unsigned long long) mddev->reshape_position); 2187 return -EINVAL; 2188 } 2189 } 2190 2191 /* 2192 * Now we set the Faulty bit for those devices that are 2193 * recorded in the superblock as failed. 2194 */ 2195 sb_retrieve_failed_devices(sb, failed_devices); 2196 rdev_for_each(r, mddev) { 2197 if (!r->sb_page) 2198 continue; 2199 sb2 = page_address(r->sb_page); 2200 sb2->failed_devices = 0; 2201 memset(sb2->extended_failed_devices, 0, sizeof(sb2->extended_failed_devices)); 2202 2203 /* 2204 * Check for any device re-ordering. 2205 */ 2206 if (!test_bit(FirstUse, &r->flags) && (r->raid_disk >= 0)) { 2207 role = le32_to_cpu(sb2->array_position); 2208 if (role < 0) 2209 continue; 2210 2211 if (role != r->raid_disk) { 2212 if (__is_raid10_near(mddev->layout)) { 2213 if (mddev->raid_disks % __raid10_near_copies(mddev->layout) || 2214 rs->raid_disks % rs->raid10_copies) { 2215 rs->ti->error = 2216 "Cannot change raid10 near set to odd # of devices!"; 2217 return -EINVAL; 2218 } 2219 2220 sb2->array_position = cpu_to_le32(r->raid_disk); 2221 2222 } else if (!(rs_is_raid10(rs) && rt_is_raid0(rs->raid_type)) && 2223 !(rs_is_raid0(rs) && rt_is_raid10(rs->raid_type)) && 2224 !rt_is_raid1(rs->raid_type)) { 2225 rs->ti->error = "Cannot change device positions in raid set"; 2226 return -EINVAL; 2227 } 2228 2229 DMINFO("raid device #%d now at position #%d", role, r->raid_disk); 2230 } 2231 2232 /* 2233 * Partial recovery is performed on 2234 * returning failed devices. 2235 */ 2236 if (test_bit(role, (void *) failed_devices)) 2237 set_bit(Faulty, &r->flags); 2238 } 2239 } 2240 2241 return 0; 2242 } 2243 2244 static int super_validate(struct raid_set *rs, struct md_rdev *rdev) 2245 { 2246 struct mddev *mddev = &rs->md; 2247 struct dm_raid_superblock *sb; 2248 2249 if (rs_is_raid0(rs) || !rdev->sb_page) 2250 return 0; 2251 2252 sb = page_address(rdev->sb_page); 2253 2254 /* 2255 * If mddev->events is not set, we know we have not yet initialized 2256 * the array. 2257 */ 2258 if (!mddev->events && super_init_validation(rs, rdev)) 2259 return -EINVAL; 2260 2261 if (le32_to_cpu(sb->compat_features) != FEATURE_FLAG_SUPPORTS_V190) { 2262 rs->ti->error = "Unable to assemble array: Unknown flag(s) in compatible feature flags"; 2263 return -EINVAL; 2264 } 2265 2266 if (sb->incompat_features) { 2267 rs->ti->error = "Unable to assemble array: No incompatible feature flags supported yet"; 2268 return -EINVAL; 2269 } 2270 2271 /* Enable bitmap creation for RAID levels != 0 */ 2272 mddev->bitmap_info.offset = rt_is_raid0(rs->raid_type) ? 0 : to_sector(4096); 2273 rdev->mddev->bitmap_info.default_offset = mddev->bitmap_info.offset; 2274 2275 if (!test_and_clear_bit(FirstUse, &rdev->flags)) { 2276 /* Retrieve device size stored in superblock to be prepared for shrink */ 2277 rdev->sectors = le64_to_cpu(sb->sectors); 2278 rdev->recovery_offset = le64_to_cpu(sb->disk_recovery_offset); 2279 if (rdev->recovery_offset == MaxSector) 2280 set_bit(In_sync, &rdev->flags); 2281 /* 2282 * If no reshape in progress -> we're recovering single 2283 * disk(s) and have to set the device(s) to out-of-sync 2284 */ 2285 else if (!rs_is_reshaping(rs)) 2286 clear_bit(In_sync, &rdev->flags); /* Mandatory for recovery */ 2287 } 2288 2289 /* 2290 * If a device comes back, set it as not In_sync and no longer faulty. 2291 */ 2292 if (test_and_clear_bit(Faulty, &rdev->flags)) { 2293 rdev->recovery_offset = 0; 2294 clear_bit(In_sync, &rdev->flags); 2295 rdev->saved_raid_disk = rdev->raid_disk; 2296 } 2297 2298 /* Reshape support -> restore repective data offsets */ 2299 rdev->data_offset = le64_to_cpu(sb->data_offset); 2300 rdev->new_data_offset = le64_to_cpu(sb->new_data_offset); 2301 2302 return 0; 2303 } 2304 2305 /* 2306 * Analyse superblocks and select the freshest. 2307 */ 2308 static int analyse_superblocks(struct dm_target *ti, struct raid_set *rs) 2309 { 2310 int r; 2311 struct raid_dev *dev; 2312 struct md_rdev *rdev, *tmp, *freshest; 2313 struct mddev *mddev = &rs->md; 2314 2315 freshest = NULL; 2316 rdev_for_each_safe(rdev, tmp, mddev) { 2317 /* 2318 * Skipping super_load due to CTR_FLAG_SYNC will cause 2319 * the array to undergo initialization again as 2320 * though it were new. This is the intended effect 2321 * of the "sync" directive. 2322 * 2323 * When reshaping capability is added, we must ensure 2324 * that the "sync" directive is disallowed during the 2325 * reshape. 2326 */ 2327 if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags)) 2328 continue; 2329 2330 if (!rdev->meta_bdev) 2331 continue; 2332 2333 r = super_load(rdev, freshest); 2334 2335 switch (r) { 2336 case 1: 2337 freshest = rdev; 2338 break; 2339 case 0: 2340 break; 2341 default: 2342 /* 2343 * We have to keep any raid0 data/metadata device pairs or 2344 * the MD raid0 personality will fail to start the array. 2345 */ 2346 if (rs_is_raid0(rs)) 2347 continue; 2348 2349 dev = container_of(rdev, struct raid_dev, rdev); 2350 if (dev->meta_dev) 2351 dm_put_device(ti, dev->meta_dev); 2352 2353 dev->meta_dev = NULL; 2354 rdev->meta_bdev = NULL; 2355 2356 if (rdev->sb_page) 2357 put_page(rdev->sb_page); 2358 2359 rdev->sb_page = NULL; 2360 2361 rdev->sb_loaded = 0; 2362 2363 /* 2364 * We might be able to salvage the data device 2365 * even though the meta device has failed. For 2366 * now, we behave as though '- -' had been 2367 * set for this device in the table. 2368 */ 2369 if (dev->data_dev) 2370 dm_put_device(ti, dev->data_dev); 2371 2372 dev->data_dev = NULL; 2373 rdev->bdev = NULL; 2374 2375 list_del(&rdev->same_set); 2376 } 2377 } 2378 2379 if (!freshest) 2380 return 0; 2381 2382 if (validate_raid_redundancy(rs)) { 2383 rs->ti->error = "Insufficient redundancy to activate array"; 2384 return -EINVAL; 2385 } 2386 2387 /* 2388 * Validation of the freshest device provides the source of 2389 * validation for the remaining devices. 2390 */ 2391 rs->ti->error = "Unable to assemble array: Invalid superblocks"; 2392 if (super_validate(rs, freshest)) 2393 return -EINVAL; 2394 2395 rdev_for_each(rdev, mddev) 2396 if ((rdev != freshest) && super_validate(rs, rdev)) 2397 return -EINVAL; 2398 return 0; 2399 } 2400 2401 /* 2402 * Adjust data_offset and new_data_offset on all disk members of @rs 2403 * for out of place reshaping if requested by contructor 2404 * 2405 * We need free space at the beginning of each raid disk for forward 2406 * and at the end for backward reshapes which userspace has to provide 2407 * via remapping/reordering of space. 2408 */ 2409 static int rs_adjust_data_offsets(struct raid_set *rs) 2410 { 2411 sector_t data_offset = 0, new_data_offset = 0; 2412 struct md_rdev *rdev; 2413 2414 /* Constructor did not request data offset change */ 2415 if (!test_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags)) { 2416 if (!rs_is_reshapable(rs)) 2417 goto out; 2418 2419 return 0; 2420 } 2421 2422 /* HM FIXME: get InSync raid_dev? */ 2423 rdev = &rs->dev[0].rdev; 2424 2425 if (rs->delta_disks < 0) { 2426 /* 2427 * Removing disks (reshaping backwards): 2428 * 2429 * - before reshape: data is at offset 0 and free space 2430 * is at end of each component LV 2431 * 2432 * - after reshape: data is at offset rs->data_offset != 0 on each component LV 2433 */ 2434 data_offset = 0; 2435 new_data_offset = rs->data_offset; 2436 2437 } else if (rs->delta_disks > 0) { 2438 /* 2439 * Adding disks (reshaping forwards): 2440 * 2441 * - before reshape: data is at offset rs->data_offset != 0 and 2442 * free space is at begin of each component LV 2443 * 2444 * - after reshape: data is at offset 0 on each component LV 2445 */ 2446 data_offset = rs->data_offset; 2447 new_data_offset = 0; 2448 2449 } else { 2450 /* 2451 * User space passes in 0 for data offset after having removed reshape space 2452 * 2453 * - or - (data offset != 0) 2454 * 2455 * Changing RAID layout or chunk size -> toggle offsets 2456 * 2457 * - before reshape: data is at offset rs->data_offset 0 and 2458 * free space is at end of each component LV 2459 * -or- 2460 * data is at offset rs->data_offset != 0 and 2461 * free space is at begin of each component LV 2462 * 2463 * - after reshape: data is at offset 0 if it was at offset != 0 2464 * or at offset != 0 if it was at offset 0 2465 * on each component LV 2466 * 2467 */ 2468 data_offset = rs->data_offset ? rdev->data_offset : 0; 2469 new_data_offset = data_offset ? 0 : rs->data_offset; 2470 set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags); 2471 } 2472 2473 /* 2474 * Make sure we got a minimum amount of free sectors per device 2475 */ 2476 if (rs->data_offset && 2477 to_sector(i_size_read(rdev->bdev->bd_inode)) - rdev->sectors < MIN_FREE_RESHAPE_SPACE) { 2478 rs->ti->error = data_offset ? "No space for forward reshape" : 2479 "No space for backward reshape"; 2480 return -ENOSPC; 2481 } 2482 out: 2483 /* Adjust data offsets on all rdevs */ 2484 rdev_for_each(rdev, &rs->md) { 2485 rdev->data_offset = data_offset; 2486 rdev->new_data_offset = new_data_offset; 2487 } 2488 2489 return 0; 2490 } 2491 2492 /* Userpace reordered disks -> adjust raid_disk indexes in @rs */ 2493 static void __reorder_raid_disk_indexes(struct raid_set *rs) 2494 { 2495 int i = 0; 2496 struct md_rdev *rdev; 2497 2498 rdev_for_each(rdev, &rs->md) { 2499 rdev->raid_disk = i++; 2500 rdev->saved_raid_disk = rdev->new_raid_disk = -1; 2501 } 2502 } 2503 2504 /* 2505 * Setup @rs for takeover by a different raid level 2506 */ 2507 static int rs_setup_takeover(struct raid_set *rs) 2508 { 2509 struct mddev *mddev = &rs->md; 2510 struct md_rdev *rdev; 2511 unsigned int d = mddev->raid_disks = rs->raid_disks; 2512 sector_t new_data_offset = rs->dev[0].rdev.data_offset ? 0 : rs->data_offset; 2513 2514 if (rt_is_raid10(rs->raid_type)) { 2515 if (mddev->level == 0) { 2516 /* Userpace reordered disks -> adjust raid_disk indexes */ 2517 __reorder_raid_disk_indexes(rs); 2518 2519 /* raid0 -> raid10_far layout */ 2520 mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_FAR, 2521 rs->raid10_copies); 2522 } else if (mddev->level == 1) 2523 /* raid1 -> raid10_near layout */ 2524 mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_NEAR, 2525 rs->raid_disks); 2526 else 2527 return -EINVAL; 2528 2529 } 2530 2531 clear_bit(MD_ARRAY_FIRST_USE, &mddev->flags); 2532 mddev->recovery_cp = MaxSector; 2533 2534 while (d--) { 2535 rdev = &rs->dev[d].rdev; 2536 2537 if (test_bit(d, (void *) rs->rebuild_disks)) { 2538 clear_bit(In_sync, &rdev->flags); 2539 clear_bit(Faulty, &rdev->flags); 2540 mddev->recovery_cp = rdev->recovery_offset = 0; 2541 /* Bitmap has to be created when we do an "up" takeover */ 2542 set_bit(MD_ARRAY_FIRST_USE, &mddev->flags); 2543 } 2544 2545 rdev->new_data_offset = new_data_offset; 2546 } 2547 2548 return 0; 2549 } 2550 2551 /* Prepare @rs for reshape */ 2552 static int rs_prepare_reshape(struct raid_set *rs) 2553 { 2554 bool reshape; 2555 struct mddev *mddev = &rs->md; 2556 2557 if (rs_is_raid10(rs)) { 2558 if (rs->raid_disks != mddev->raid_disks && 2559 __is_raid10_near(mddev->layout) && 2560 rs->raid10_copies && 2561 rs->raid10_copies != __raid10_near_copies(mddev->layout)) { 2562 /* 2563 * raid disk have to be multiple of data copies to allow this conversion, 2564 * 2565 * This is actually not a reshape it is a 2566 * rebuild of any additional mirrors per group 2567 */ 2568 if (rs->raid_disks % rs->raid10_copies) { 2569 rs->ti->error = "Can't reshape raid10 mirror groups"; 2570 return -EINVAL; 2571 } 2572 2573 /* Userpace reordered disks to add/remove mirrors -> adjust raid_disk indexes */ 2574 __reorder_raid_disk_indexes(rs); 2575 mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_NEAR, 2576 rs->raid10_copies); 2577 mddev->new_layout = mddev->layout; 2578 reshape = false; 2579 } else 2580 reshape = true; 2581 2582 } else if (rs_is_raid456(rs)) 2583 reshape = true; 2584 2585 else if (rs_is_raid1(rs)) { 2586 if (rs->delta_disks) { 2587 /* Process raid1 via delta_disks */ 2588 mddev->degraded = rs->delta_disks < 0 ? -rs->delta_disks : rs->delta_disks; 2589 reshape = true; 2590 } else { 2591 /* Process raid1 without delta_disks */ 2592 mddev->raid_disks = rs->raid_disks; 2593 reshape = false; 2594 } 2595 } else { 2596 rs->ti->error = "Called with bogus raid type"; 2597 return -EINVAL; 2598 } 2599 2600 if (reshape) { 2601 set_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags); 2602 set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags); 2603 } else if (mddev->raid_disks < rs->raid_disks) 2604 /* Create new superblocks and bitmaps, if any new disks */ 2605 set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags); 2606 2607 return 0; 2608 } 2609 2610 /* 2611 * 2612 * - change raid layout 2613 * - change chunk size 2614 * - add disks 2615 * - remove disks 2616 */ 2617 static int rs_setup_reshape(struct raid_set *rs) 2618 { 2619 int r = 0; 2620 unsigned int cur_raid_devs, d; 2621 struct mddev *mddev = &rs->md; 2622 struct md_rdev *rdev; 2623 2624 mddev->delta_disks = rs->delta_disks; 2625 cur_raid_devs = mddev->raid_disks; 2626 2627 /* Ignore impossible layout change whilst adding/removing disks */ 2628 if (mddev->delta_disks && 2629 mddev->layout != mddev->new_layout) { 2630 DMINFO("Ignoring invalid layout change with delta_disks=%d", rs->delta_disks); 2631 mddev->new_layout = mddev->layout; 2632 } 2633 2634 /* 2635 * Adjust array size: 2636 * 2637 * - in case of adding disks, array size has 2638 * to grow after the disk adding reshape, 2639 * which'll hapen in the event handler; 2640 * reshape will happen forward, so space has to 2641 * be available at the beginning of each disk 2642 * 2643 * - in case of removing disks, array size 2644 * has to shrink before starting the reshape, 2645 * which'll happen here; 2646 * reshape will happen backward, so space has to 2647 * be available at the end of each disk 2648 * 2649 * - data_offset and new_data_offset are 2650 * adjusted for aforementioned out of place 2651 * reshaping based on userspace passing in 2652 * the "data_offset <sectors>" key/value 2653 * pair via the constructor 2654 */ 2655 2656 /* Add disk(s) */ 2657 if (rs->delta_disks > 0) { 2658 /* Prepare disks for check in raid4/5/6/10 {check|start}_reshape */ 2659 for (d = cur_raid_devs; d < rs->raid_disks; d++) { 2660 rdev = &rs->dev[d].rdev; 2661 clear_bit(In_sync, &rdev->flags); 2662 2663 /* 2664 * save_raid_disk needs to be -1, or recovery_offset will be set to 0 2665 * by md, which'll store that erroneously in the superblock on reshape 2666 */ 2667 rdev->saved_raid_disk = -1; 2668 rdev->raid_disk = d; 2669 2670 rdev->sectors = mddev->dev_sectors; 2671 rdev->recovery_offset = rs_is_raid1(rs) ? 0 : MaxSector; 2672 } 2673 2674 mddev->reshape_backwards = 0; /* adding disks -> forward reshape */ 2675 2676 /* Remove disk(s) */ 2677 } else if (rs->delta_disks < 0) { 2678 r = rs_set_dev_and_array_sectors(rs, true); 2679 mddev->reshape_backwards = 1; /* removing disk(s) -> backward reshape */ 2680 2681 /* Change layout and/or chunk size */ 2682 } else { 2683 /* 2684 * Reshape layout (e.g. raid5_ls -> raid5_n) and/or chunk size: 2685 * 2686 * keeping number of disks and do layout change -> 2687 * 2688 * toggle reshape_backward depending on data_offset: 2689 * 2690 * - free space upfront -> reshape forward 2691 * 2692 * - free space at the end -> reshape backward 2693 * 2694 * 2695 * This utilizes free reshape space avoiding the need 2696 * for userspace to move (parts of) LV segments in 2697 * case of layout/chunksize change (for disk 2698 * adding/removing reshape space has to be at 2699 * the proper address (see above with delta_disks): 2700 * 2701 * add disk(s) -> begin 2702 * remove disk(s)-> end 2703 */ 2704 mddev->reshape_backwards = rs->dev[0].rdev.data_offset ? 0 : 1; 2705 } 2706 2707 return r; 2708 } 2709 2710 /* 2711 * Enable/disable discard support on RAID set depending on 2712 * RAID level and discard properties of underlying RAID members. 2713 */ 2714 static void configure_discard_support(struct raid_set *rs) 2715 { 2716 int i; 2717 bool raid456; 2718 struct dm_target *ti = rs->ti; 2719 2720 /* Assume discards not supported until after checks below. */ 2721 ti->discards_supported = false; 2722 2723 /* RAID level 4,5,6 require discard_zeroes_data for data integrity! */ 2724 raid456 = (rs->md.level == 4 || rs->md.level == 5 || rs->md.level == 6); 2725 2726 for (i = 0; i < rs->raid_disks; i++) { 2727 struct request_queue *q; 2728 2729 if (!rs->dev[i].rdev.bdev) 2730 continue; 2731 2732 q = bdev_get_queue(rs->dev[i].rdev.bdev); 2733 if (!q || !blk_queue_discard(q)) 2734 return; 2735 2736 if (raid456) { 2737 if (!q->limits.discard_zeroes_data) 2738 return; 2739 if (!devices_handle_discard_safely) { 2740 DMERR("raid456 discard support disabled due to discard_zeroes_data uncertainty."); 2741 DMERR("Set dm-raid.devices_handle_discard_safely=Y to override."); 2742 return; 2743 } 2744 } 2745 } 2746 2747 /* All RAID members properly support discards */ 2748 ti->discards_supported = true; 2749 2750 /* 2751 * RAID1 and RAID10 personalities require bio splitting, 2752 * RAID0/4/5/6 don't and process large discard bios properly. 2753 */ 2754 ti->split_discard_bios = !!(rs->md.level == 1 || rs->md.level == 10); 2755 ti->num_discard_bios = 1; 2756 } 2757 2758 /* 2759 * Construct a RAID0/1/10/4/5/6 mapping: 2760 * Args: 2761 * <raid_type> <#raid_params> <raid_params>{0,} \ 2762 * <#raid_devs> [<meta_dev1> <dev1>]{1,} 2763 * 2764 * <raid_params> varies by <raid_type>. See 'parse_raid_params' for 2765 * details on possible <raid_params>. 2766 * 2767 * Userspace is free to initialize the metadata devices, hence the superblocks to 2768 * enforce recreation based on the passed in table parameters. 2769 * 2770 */ 2771 static int raid_ctr(struct dm_target *ti, unsigned int argc, char **argv) 2772 { 2773 int r; 2774 bool resize; 2775 struct raid_type *rt; 2776 unsigned int num_raid_params, num_raid_devs; 2777 sector_t calculated_dev_sectors; 2778 struct raid_set *rs = NULL; 2779 const char *arg; 2780 struct rs_layout rs_layout; 2781 struct dm_arg_set as = { argc, argv }, as_nrd; 2782 struct dm_arg _args[] = { 2783 { 0, as.argc, "Cannot understand number of raid parameters" }, 2784 { 1, 254, "Cannot understand number of raid devices parameters" } 2785 }; 2786 2787 /* Must have <raid_type> */ 2788 arg = dm_shift_arg(&as); 2789 if (!arg) { 2790 ti->error = "No arguments"; 2791 return -EINVAL; 2792 } 2793 2794 rt = get_raid_type(arg); 2795 if (!rt) { 2796 ti->error = "Unrecognised raid_type"; 2797 return -EINVAL; 2798 } 2799 2800 /* Must have <#raid_params> */ 2801 if (dm_read_arg_group(_args, &as, &num_raid_params, &ti->error)) 2802 return -EINVAL; 2803 2804 /* number of raid device tupples <meta_dev data_dev> */ 2805 as_nrd = as; 2806 dm_consume_args(&as_nrd, num_raid_params); 2807 _args[1].max = (as_nrd.argc - 1) / 2; 2808 if (dm_read_arg(_args + 1, &as_nrd, &num_raid_devs, &ti->error)) 2809 return -EINVAL; 2810 2811 if (!__within_range(num_raid_devs, 1, MAX_RAID_DEVICES)) { 2812 ti->error = "Invalid number of supplied raid devices"; 2813 return -EINVAL; 2814 } 2815 2816 rs = raid_set_alloc(ti, rt, num_raid_devs); 2817 if (IS_ERR(rs)) 2818 return PTR_ERR(rs); 2819 2820 r = parse_raid_params(rs, &as, num_raid_params); 2821 if (r) 2822 goto bad; 2823 2824 r = parse_dev_params(rs, &as); 2825 if (r) 2826 goto bad; 2827 2828 rs->md.sync_super = super_sync; 2829 2830 /* 2831 * Calculate ctr requested array and device sizes to allow 2832 * for superblock analysis needing device sizes defined. 2833 * 2834 * Any existing superblock will overwrite the array and device sizes 2835 */ 2836 r = rs_set_dev_and_array_sectors(rs, false); 2837 if (r) 2838 goto bad; 2839 2840 calculated_dev_sectors = rs->dev[0].rdev.sectors; 2841 2842 /* 2843 * Backup any new raid set level, layout, ... 2844 * requested to be able to compare to superblock 2845 * members for conversion decisions. 2846 */ 2847 rs_config_backup(rs, &rs_layout); 2848 2849 r = analyse_superblocks(ti, rs); 2850 if (r) 2851 goto bad; 2852 2853 resize = calculated_dev_sectors != rs->dev[0].rdev.sectors; 2854 2855 INIT_WORK(&rs->md.event_work, do_table_event); 2856 ti->private = rs; 2857 ti->num_flush_bios = 1; 2858 2859 /* Restore any requested new layout for conversion decision */ 2860 rs_config_restore(rs, &rs_layout); 2861 2862 /* 2863 * Now that we have any superblock metadata available, 2864 * check for new, recovering, reshaping, to be taken over, 2865 * to be reshaped or an existing, unchanged raid set to 2866 * run in sequence. 2867 */ 2868 if (test_bit(MD_ARRAY_FIRST_USE, &rs->md.flags)) { 2869 /* A new raid6 set has to be recovered to ensure proper parity and Q-Syndrome */ 2870 if (rs_is_raid6(rs) && 2871 test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) { 2872 ti->error = "'nosync' not allowed for new raid6 set"; 2873 r = -EINVAL; 2874 goto bad; 2875 } 2876 rs_setup_recovery(rs, 0); 2877 set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags); 2878 rs_set_new(rs); 2879 } else if (rs_is_recovering(rs)) { 2880 /* A recovering raid set may be resized */ 2881 ; /* skip setup rs */ 2882 } else if (rs_is_reshaping(rs)) { 2883 /* Have to reject size change request during reshape */ 2884 if (resize) { 2885 ti->error = "Can't resize a reshaping raid set"; 2886 r = -EPERM; 2887 goto bad; 2888 } 2889 /* skip setup rs */ 2890 } else if (rs_takeover_requested(rs)) { 2891 if (rs_is_reshaping(rs)) { 2892 ti->error = "Can't takeover a reshaping raid set"; 2893 r = -EPERM; 2894 goto bad; 2895 } 2896 2897 /* 2898 * If a takeover is needed, userspace sets any additional 2899 * devices to rebuild and we can check for a valid request here. 2900 * 2901 * If acceptible, set the level to the new requested 2902 * one, prohibit requesting recovery, allow the raid 2903 * set to run and store superblocks during resume. 2904 */ 2905 r = rs_check_takeover(rs); 2906 if (r) 2907 goto bad; 2908 2909 r = rs_setup_takeover(rs); 2910 if (r) 2911 goto bad; 2912 2913 set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags); 2914 /* Takeover ain't recovery, so disable recovery */ 2915 rs_setup_recovery(rs, MaxSector); 2916 rs_set_new(rs); 2917 } else if (rs_reshape_requested(rs)) { 2918 /* 2919 * We can only prepare for a reshape here, because the 2920 * raid set needs to run to provide the repective reshape 2921 * check functions via its MD personality instance. 2922 * 2923 * So do the reshape check after md_run() succeeded. 2924 */ 2925 r = rs_prepare_reshape(rs); 2926 if (r) 2927 return r; 2928 2929 /* Reshaping ain't recovery, so disable recovery */ 2930 rs_setup_recovery(rs, MaxSector); 2931 rs_set_cur(rs); 2932 } else { 2933 /* May not set recovery when a device rebuild is requested */ 2934 if (test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags)) { 2935 rs_setup_recovery(rs, MaxSector); 2936 set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags); 2937 } else 2938 rs_setup_recovery(rs, test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags) ? 2939 0 : (resize ? calculated_dev_sectors : MaxSector)); 2940 rs_set_cur(rs); 2941 } 2942 2943 /* If constructor requested it, change data and new_data offsets */ 2944 r = rs_adjust_data_offsets(rs); 2945 if (r) 2946 goto bad; 2947 2948 /* Start raid set read-only and assumed clean to change in raid_resume() */ 2949 rs->md.ro = 1; 2950 rs->md.in_sync = 1; 2951 set_bit(MD_RECOVERY_FROZEN, &rs->md.recovery); 2952 2953 /* Has to be held on running the array */ 2954 mddev_lock_nointr(&rs->md); 2955 r = md_run(&rs->md); 2956 rs->md.in_sync = 0; /* Assume already marked dirty */ 2957 2958 if (r) { 2959 ti->error = "Failed to run raid array"; 2960 mddev_unlock(&rs->md); 2961 goto bad; 2962 } 2963 2964 rs->callbacks.congested_fn = raid_is_congested; 2965 dm_table_add_target_callbacks(ti->table, &rs->callbacks); 2966 2967 mddev_suspend(&rs->md); 2968 2969 /* Try to adjust the raid4/5/6 stripe cache size to the stripe size */ 2970 if (rs_is_raid456(rs)) { 2971 r = rs_set_raid456_stripe_cache(rs); 2972 if (r) 2973 goto bad_stripe_cache; 2974 } 2975 2976 /* Now do an early reshape check */ 2977 if (test_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags)) { 2978 r = rs_check_reshape(rs); 2979 if (r) 2980 goto bad_check_reshape; 2981 2982 /* Restore new, ctr requested layout to perform check */ 2983 rs_config_restore(rs, &rs_layout); 2984 2985 if (rs->md.pers->start_reshape) { 2986 r = rs->md.pers->check_reshape(&rs->md); 2987 if (r) { 2988 ti->error = "Reshape check failed"; 2989 goto bad_check_reshape; 2990 } 2991 } 2992 } 2993 2994 mddev_unlock(&rs->md); 2995 return 0; 2996 2997 bad_stripe_cache: 2998 bad_check_reshape: 2999 md_stop(&rs->md); 3000 bad: 3001 raid_set_free(rs); 3002 3003 return r; 3004 } 3005 3006 static void raid_dtr(struct dm_target *ti) 3007 { 3008 struct raid_set *rs = ti->private; 3009 3010 list_del_init(&rs->callbacks.list); 3011 md_stop(&rs->md); 3012 raid_set_free(rs); 3013 } 3014 3015 static int raid_map(struct dm_target *ti, struct bio *bio) 3016 { 3017 struct raid_set *rs = ti->private; 3018 struct mddev *mddev = &rs->md; 3019 3020 /* 3021 * If we're reshaping to add disk(s)), ti->len and 3022 * mddev->array_sectors will differ during the process 3023 * (ti->len > mddev->array_sectors), so we have to requeue 3024 * bios with addresses > mddev->array_sectors here or 3025 * there will occur accesses past EOD of the component 3026 * data images thus erroring the raid set. 3027 */ 3028 if (unlikely(bio_end_sector(bio) > mddev->array_sectors)) 3029 return DM_MAPIO_REQUEUE; 3030 3031 mddev->pers->make_request(mddev, bio); 3032 3033 return DM_MAPIO_SUBMITTED; 3034 } 3035 3036 /* Return string describing the current sync action of @mddev */ 3037 static const char *decipher_sync_action(struct mddev *mddev) 3038 { 3039 if (test_bit(MD_RECOVERY_FROZEN, &mddev->recovery)) 3040 return "frozen"; 3041 3042 if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) || 3043 (!mddev->ro && test_bit(MD_RECOVERY_NEEDED, &mddev->recovery))) { 3044 if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery)) 3045 return "reshape"; 3046 3047 if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) { 3048 if (!test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) 3049 return "resync"; 3050 else if (test_bit(MD_RECOVERY_CHECK, &mddev->recovery)) 3051 return "check"; 3052 return "repair"; 3053 } 3054 3055 if (test_bit(MD_RECOVERY_RECOVER, &mddev->recovery)) 3056 return "recover"; 3057 } 3058 3059 return "idle"; 3060 } 3061 3062 /* 3063 * Return status string @rdev 3064 * 3065 * Status characters: 3066 * 3067 * 'D' = Dead/Failed device 3068 * 'a' = Alive but not in-sync 3069 * 'A' = Alive and in-sync 3070 */ 3071 static const char *__raid_dev_status(struct md_rdev *rdev, bool array_in_sync) 3072 { 3073 if (test_bit(Faulty, &rdev->flags)) 3074 return "D"; 3075 else if (!array_in_sync || !test_bit(In_sync, &rdev->flags)) 3076 return "a"; 3077 else 3078 return "A"; 3079 } 3080 3081 /* Helper to return resync/reshape progress for @rs and @array_in_sync */ 3082 static sector_t rs_get_progress(struct raid_set *rs, 3083 sector_t resync_max_sectors, bool *array_in_sync) 3084 { 3085 sector_t r, recovery_cp, curr_resync_completed; 3086 struct mddev *mddev = &rs->md; 3087 3088 curr_resync_completed = mddev->curr_resync_completed ?: mddev->recovery_cp; 3089 recovery_cp = mddev->recovery_cp; 3090 *array_in_sync = false; 3091 3092 if (rs_is_raid0(rs)) { 3093 r = resync_max_sectors; 3094 *array_in_sync = true; 3095 3096 } else { 3097 r = mddev->reshape_position; 3098 3099 /* Reshape is relative to the array size */ 3100 if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery) || 3101 r != MaxSector) { 3102 if (r == MaxSector) { 3103 *array_in_sync = true; 3104 r = resync_max_sectors; 3105 } else { 3106 /* Got to reverse on backward reshape */ 3107 if (mddev->reshape_backwards) 3108 r = mddev->array_sectors - r; 3109 3110 /* Devide by # of data stripes */ 3111 sector_div(r, mddev_data_stripes(rs)); 3112 } 3113 3114 /* Sync is relative to the component device size */ 3115 } else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery)) 3116 r = curr_resync_completed; 3117 else 3118 r = recovery_cp; 3119 3120 if (r == MaxSector) { 3121 /* 3122 * Sync complete. 3123 */ 3124 *array_in_sync = true; 3125 r = resync_max_sectors; 3126 } else if (test_bit(MD_RECOVERY_REQUESTED, &mddev->recovery)) { 3127 /* 3128 * If "check" or "repair" is occurring, the raid set has 3129 * undergone an initial sync and the health characters 3130 * should not be 'a' anymore. 3131 */ 3132 *array_in_sync = true; 3133 } else { 3134 struct md_rdev *rdev; 3135 3136 /* 3137 * The raid set may be doing an initial sync, or it may 3138 * be rebuilding individual components. If all the 3139 * devices are In_sync, then it is the raid set that is 3140 * being initialized. 3141 */ 3142 rdev_for_each(rdev, mddev) 3143 if (!test_bit(In_sync, &rdev->flags)) 3144 *array_in_sync = true; 3145 #if 0 3146 r = 0; /* HM FIXME: TESTME: https://bugzilla.redhat.com/show_bug.cgi?id=1210637 ? */ 3147 #endif 3148 } 3149 } 3150 3151 return r; 3152 } 3153 3154 /* Helper to return @dev name or "-" if !@dev */ 3155 static const char *__get_dev_name(struct dm_dev *dev) 3156 { 3157 return dev ? dev->name : "-"; 3158 } 3159 3160 static void raid_status(struct dm_target *ti, status_type_t type, 3161 unsigned int status_flags, char *result, unsigned int maxlen) 3162 { 3163 struct raid_set *rs = ti->private; 3164 struct mddev *mddev = &rs->md; 3165 struct r5conf *conf = mddev->private; 3166 int i, max_nr_stripes = conf ? conf->max_nr_stripes : 0; 3167 bool array_in_sync; 3168 unsigned int raid_param_cnt = 1; /* at least 1 for chunksize */ 3169 unsigned int sz = 0; 3170 unsigned int rebuild_disks; 3171 unsigned int write_mostly_params = 0; 3172 sector_t progress, resync_max_sectors, resync_mismatches; 3173 const char *sync_action; 3174 struct raid_type *rt; 3175 struct md_rdev *rdev; 3176 3177 switch (type) { 3178 case STATUSTYPE_INFO: 3179 /* *Should* always succeed */ 3180 rt = get_raid_type_by_ll(mddev->new_level, mddev->new_layout); 3181 if (!rt) 3182 return; 3183 3184 DMEMIT("%s %d ", rt->name, mddev->raid_disks); 3185 3186 /* Access most recent mddev properties for status output */ 3187 smp_rmb(); 3188 /* Get sensible max sectors even if raid set not yet started */ 3189 resync_max_sectors = test_bit(RT_FLAG_RS_PRERESUMED, &rs->runtime_flags) ? 3190 mddev->resync_max_sectors : mddev->dev_sectors; 3191 progress = rs_get_progress(rs, resync_max_sectors, &array_in_sync); 3192 resync_mismatches = (mddev->last_sync_action && !strcasecmp(mddev->last_sync_action, "check")) ? 3193 atomic64_read(&mddev->resync_mismatches) : 0; 3194 sync_action = decipher_sync_action(&rs->md); 3195 3196 /* HM FIXME: do we want another state char for raid0? It shows 'D' or 'A' now */ 3197 rdev_for_each(rdev, mddev) 3198 DMEMIT(__raid_dev_status(rdev, array_in_sync)); 3199 3200 /* 3201 * In-sync/Reshape ratio: 3202 * The in-sync ratio shows the progress of: 3203 * - Initializing the raid set 3204 * - Rebuilding a subset of devices of the raid set 3205 * The user can distinguish between the two by referring 3206 * to the status characters. 3207 * 3208 * The reshape ratio shows the progress of 3209 * changing the raid layout or the number of 3210 * disks of a raid set 3211 */ 3212 DMEMIT(" %llu/%llu", (unsigned long long) progress, 3213 (unsigned long long) resync_max_sectors); 3214 3215 /* 3216 * v1.5.0+: 3217 * 3218 * Sync action: 3219 * See Documentation/device-mapper/dm-raid.txt for 3220 * information on each of these states. 3221 */ 3222 DMEMIT(" %s", sync_action); 3223 3224 /* 3225 * v1.5.0+: 3226 * 3227 * resync_mismatches/mismatch_cnt 3228 * This field shows the number of discrepancies found when 3229 * performing a "check" of the raid set. 3230 */ 3231 DMEMIT(" %llu", (unsigned long long) resync_mismatches); 3232 3233 /* 3234 * v1.9.0+: 3235 * 3236 * data_offset (needed for out of space reshaping) 3237 * This field shows the data offset into the data 3238 * image LV where the first stripes data starts. 3239 * 3240 * We keep data_offset equal on all raid disks of the set, 3241 * so retrieving it from the first raid disk is sufficient. 3242 */ 3243 DMEMIT(" %llu", (unsigned long long) rs->dev[0].rdev.data_offset); 3244 break; 3245 3246 case STATUSTYPE_TABLE: 3247 /* Report the table line string you would use to construct this raid set */ 3248 3249 /* Calculate raid parameter count */ 3250 for (i = 0; i < rs->raid_disks; i++) 3251 if (test_bit(WriteMostly, &rs->dev[i].rdev.flags)) 3252 write_mostly_params += 2; 3253 rebuild_disks = memweight(rs->rebuild_disks, DISKS_ARRAY_ELEMS * sizeof(*rs->rebuild_disks)); 3254 raid_param_cnt += rebuild_disks * 2 + 3255 write_mostly_params + 3256 hweight32(rs->ctr_flags & CTR_FLAG_OPTIONS_NO_ARGS) + 3257 hweight32(rs->ctr_flags & CTR_FLAG_OPTIONS_ONE_ARG) * 2; 3258 /* Emit table line */ 3259 DMEMIT("%s %u %u", rs->raid_type->name, raid_param_cnt, mddev->new_chunk_sectors); 3260 if (test_bit(__CTR_FLAG_RAID10_FORMAT, &rs->ctr_flags)) 3261 DMEMIT(" %s %s", dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_FORMAT), 3262 raid10_md_layout_to_format(mddev->layout)); 3263 if (test_bit(__CTR_FLAG_RAID10_COPIES, &rs->ctr_flags)) 3264 DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_COPIES), 3265 raid10_md_layout_to_copies(mddev->layout)); 3266 if (test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) 3267 DMEMIT(" %s", dm_raid_arg_name_by_flag(CTR_FLAG_NOSYNC)); 3268 if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags)) 3269 DMEMIT(" %s", dm_raid_arg_name_by_flag(CTR_FLAG_SYNC)); 3270 if (test_bit(__CTR_FLAG_REGION_SIZE, &rs->ctr_flags)) 3271 DMEMIT(" %s %llu", dm_raid_arg_name_by_flag(CTR_FLAG_REGION_SIZE), 3272 (unsigned long long) to_sector(mddev->bitmap_info.chunksize)); 3273 if (test_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags)) 3274 DMEMIT(" %s %llu", dm_raid_arg_name_by_flag(CTR_FLAG_DATA_OFFSET), 3275 (unsigned long long) rs->data_offset); 3276 if (test_bit(__CTR_FLAG_DAEMON_SLEEP, &rs->ctr_flags)) 3277 DMEMIT(" %s %lu", dm_raid_arg_name_by_flag(CTR_FLAG_DAEMON_SLEEP), 3278 mddev->bitmap_info.daemon_sleep); 3279 if (test_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags)) 3280 DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_DELTA_DISKS), 3281 max(rs->delta_disks, mddev->delta_disks)); 3282 if (test_bit(__CTR_FLAG_STRIPE_CACHE, &rs->ctr_flags)) 3283 DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_STRIPE_CACHE), 3284 max_nr_stripes); 3285 if (rebuild_disks) 3286 for (i = 0; i < rs->raid_disks; i++) 3287 if (test_bit(rs->dev[i].rdev.raid_disk, (void *) rs->rebuild_disks)) 3288 DMEMIT(" %s %u", dm_raid_arg_name_by_flag(CTR_FLAG_REBUILD), 3289 rs->dev[i].rdev.raid_disk); 3290 if (write_mostly_params) 3291 for (i = 0; i < rs->raid_disks; i++) 3292 if (test_bit(WriteMostly, &rs->dev[i].rdev.flags)) 3293 DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_WRITE_MOSTLY), 3294 rs->dev[i].rdev.raid_disk); 3295 if (test_bit(__CTR_FLAG_MAX_WRITE_BEHIND, &rs->ctr_flags)) 3296 DMEMIT(" %s %lu", dm_raid_arg_name_by_flag(CTR_FLAG_MAX_WRITE_BEHIND), 3297 mddev->bitmap_info.max_write_behind); 3298 if (test_bit(__CTR_FLAG_MAX_RECOVERY_RATE, &rs->ctr_flags)) 3299 DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_MAX_RECOVERY_RATE), 3300 mddev->sync_speed_max); 3301 if (test_bit(__CTR_FLAG_MIN_RECOVERY_RATE, &rs->ctr_flags)) 3302 DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_MIN_RECOVERY_RATE), 3303 mddev->sync_speed_min); 3304 DMEMIT(" %d", rs->raid_disks); 3305 for (i = 0; i < rs->raid_disks; i++) 3306 DMEMIT(" %s %s", __get_dev_name(rs->dev[i].meta_dev), 3307 __get_dev_name(rs->dev[i].data_dev)); 3308 } 3309 } 3310 3311 static int raid_message(struct dm_target *ti, unsigned int argc, char **argv) 3312 { 3313 struct raid_set *rs = ti->private; 3314 struct mddev *mddev = &rs->md; 3315 3316 if (!mddev->pers || !mddev->pers->sync_request) 3317 return -EINVAL; 3318 3319 if (!strcasecmp(argv[0], "frozen")) 3320 set_bit(MD_RECOVERY_FROZEN, &mddev->recovery); 3321 else 3322 clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery); 3323 3324 if (!strcasecmp(argv[0], "idle") || !strcasecmp(argv[0], "frozen")) { 3325 if (mddev->sync_thread) { 3326 set_bit(MD_RECOVERY_INTR, &mddev->recovery); 3327 md_reap_sync_thread(mddev); 3328 } 3329 } else if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery) || 3330 test_bit(MD_RECOVERY_NEEDED, &mddev->recovery)) 3331 return -EBUSY; 3332 else if (!strcasecmp(argv[0], "resync")) 3333 ; /* MD_RECOVERY_NEEDED set below */ 3334 else if (!strcasecmp(argv[0], "recover")) 3335 set_bit(MD_RECOVERY_RECOVER, &mddev->recovery); 3336 else { 3337 if (!strcasecmp(argv[0], "check")) 3338 set_bit(MD_RECOVERY_CHECK, &mddev->recovery); 3339 else if (!!strcasecmp(argv[0], "repair")) 3340 return -EINVAL; 3341 set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery); 3342 set_bit(MD_RECOVERY_SYNC, &mddev->recovery); 3343 } 3344 if (mddev->ro == 2) { 3345 /* A write to sync_action is enough to justify 3346 * canceling read-auto mode 3347 */ 3348 mddev->ro = 0; 3349 if (!mddev->suspended && mddev->sync_thread) 3350 md_wakeup_thread(mddev->sync_thread); 3351 } 3352 set_bit(MD_RECOVERY_NEEDED, &mddev->recovery); 3353 if (!mddev->suspended && mddev->thread) 3354 md_wakeup_thread(mddev->thread); 3355 3356 return 0; 3357 } 3358 3359 static int raid_iterate_devices(struct dm_target *ti, 3360 iterate_devices_callout_fn fn, void *data) 3361 { 3362 struct raid_set *rs = ti->private; 3363 unsigned int i; 3364 int r = 0; 3365 3366 for (i = 0; !r && i < rs->md.raid_disks; i++) 3367 if (rs->dev[i].data_dev) 3368 r = fn(ti, 3369 rs->dev[i].data_dev, 3370 0, /* No offset on data devs */ 3371 rs->md.dev_sectors, 3372 data); 3373 3374 return r; 3375 } 3376 3377 static void raid_io_hints(struct dm_target *ti, struct queue_limits *limits) 3378 { 3379 struct raid_set *rs = ti->private; 3380 unsigned int chunk_size = to_bytes(rs->md.chunk_sectors); 3381 3382 blk_limits_io_min(limits, chunk_size); 3383 blk_limits_io_opt(limits, chunk_size * mddev_data_stripes(rs)); 3384 } 3385 3386 static void raid_presuspend(struct dm_target *ti) 3387 { 3388 struct raid_set *rs = ti->private; 3389 3390 md_stop_writes(&rs->md); 3391 } 3392 3393 static void raid_postsuspend(struct dm_target *ti) 3394 { 3395 struct raid_set *rs = ti->private; 3396 3397 if (!rs->md.suspended) 3398 mddev_suspend(&rs->md); 3399 3400 rs->md.ro = 1; 3401 } 3402 3403 static void attempt_restore_of_faulty_devices(struct raid_set *rs) 3404 { 3405 int i; 3406 uint64_t cleared_failed_devices[DISKS_ARRAY_ELEMS]; 3407 unsigned long flags; 3408 bool cleared = false; 3409 struct dm_raid_superblock *sb; 3410 struct mddev *mddev = &rs->md; 3411 struct md_rdev *r; 3412 3413 /* RAID personalities have to provide hot add/remove methods or we need to bail out. */ 3414 if (!mddev->pers || !mddev->pers->hot_add_disk || !mddev->pers->hot_remove_disk) 3415 return; 3416 3417 memset(cleared_failed_devices, 0, sizeof(cleared_failed_devices)); 3418 3419 for (i = 0; i < rs->md.raid_disks; i++) { 3420 r = &rs->dev[i].rdev; 3421 if (test_bit(Faulty, &r->flags) && r->sb_page && 3422 sync_page_io(r, 0, r->sb_size, r->sb_page, 3423 REQ_OP_READ, 0, true)) { 3424 DMINFO("Faulty %s device #%d has readable super block." 3425 " Attempting to revive it.", 3426 rs->raid_type->name, i); 3427 3428 /* 3429 * Faulty bit may be set, but sometimes the array can 3430 * be suspended before the personalities can respond 3431 * by removing the device from the array (i.e. calling 3432 * 'hot_remove_disk'). If they haven't yet removed 3433 * the failed device, its 'raid_disk' number will be 3434 * '>= 0' - meaning we must call this function 3435 * ourselves. 3436 */ 3437 if ((r->raid_disk >= 0) && 3438 (mddev->pers->hot_remove_disk(mddev, r) != 0)) 3439 /* Failed to revive this device, try next */ 3440 continue; 3441 3442 r->raid_disk = i; 3443 r->saved_raid_disk = i; 3444 flags = r->flags; 3445 clear_bit(Faulty, &r->flags); 3446 clear_bit(WriteErrorSeen, &r->flags); 3447 clear_bit(In_sync, &r->flags); 3448 if (mddev->pers->hot_add_disk(mddev, r)) { 3449 r->raid_disk = -1; 3450 r->saved_raid_disk = -1; 3451 r->flags = flags; 3452 } else { 3453 r->recovery_offset = 0; 3454 set_bit(i, (void *) cleared_failed_devices); 3455 cleared = true; 3456 } 3457 } 3458 } 3459 3460 /* If any failed devices could be cleared, update all sbs failed_devices bits */ 3461 if (cleared) { 3462 uint64_t failed_devices[DISKS_ARRAY_ELEMS]; 3463 3464 rdev_for_each(r, &rs->md) { 3465 sb = page_address(r->sb_page); 3466 sb_retrieve_failed_devices(sb, failed_devices); 3467 3468 for (i = 0; i < DISKS_ARRAY_ELEMS; i++) 3469 failed_devices[i] &= ~cleared_failed_devices[i]; 3470 3471 sb_update_failed_devices(sb, failed_devices); 3472 } 3473 } 3474 } 3475 3476 static int __load_dirty_region_bitmap(struct raid_set *rs) 3477 { 3478 int r = 0; 3479 3480 /* Try loading the bitmap unless "raid0", which does not have one */ 3481 if (!rs_is_raid0(rs) && 3482 !test_and_set_bit(RT_FLAG_RS_BITMAP_LOADED, &rs->runtime_flags)) { 3483 r = bitmap_load(&rs->md); 3484 if (r) 3485 DMERR("Failed to load bitmap"); 3486 } 3487 3488 return r; 3489 } 3490 3491 /* Enforce updating all superblocks */ 3492 static void rs_update_sbs(struct raid_set *rs) 3493 { 3494 struct mddev *mddev = &rs->md; 3495 int ro = mddev->ro; 3496 3497 set_bit(MD_CHANGE_DEVS, &mddev->flags); 3498 mddev->ro = 0; 3499 md_update_sb(mddev, 1); 3500 mddev->ro = ro; 3501 } 3502 3503 /* 3504 * Reshape changes raid algorithm of @rs to new one within personality 3505 * (e.g. raid6_zr -> raid6_nc), changes stripe size, adds/removes 3506 * disks from a raid set thus growing/shrinking it or resizes the set 3507 * 3508 * Call mddev_lock_nointr() before! 3509 */ 3510 static int rs_start_reshape(struct raid_set *rs) 3511 { 3512 int r; 3513 struct mddev *mddev = &rs->md; 3514 struct md_personality *pers = mddev->pers; 3515 3516 r = rs_setup_reshape(rs); 3517 if (r) 3518 return r; 3519 3520 /* Need to be resumed to be able to start reshape, recovery is frozen until raid_resume() though */ 3521 if (mddev->suspended) 3522 mddev_resume(mddev); 3523 3524 /* 3525 * Check any reshape constraints enforced by the personalility 3526 * 3527 * May as well already kick the reshape off so that * pers->start_reshape() becomes optional. 3528 */ 3529 r = pers->check_reshape(mddev); 3530 if (r) { 3531 rs->ti->error = "pers->check_reshape() failed"; 3532 return r; 3533 } 3534 3535 /* 3536 * Personality may not provide start reshape method in which 3537 * case check_reshape above has already covered everything 3538 */ 3539 if (pers->start_reshape) { 3540 r = pers->start_reshape(mddev); 3541 if (r) { 3542 rs->ti->error = "pers->start_reshape() failed"; 3543 return r; 3544 } 3545 } 3546 3547 /* Suspend because a resume will happen in raid_resume() */ 3548 if (!mddev->suspended) 3549 mddev_suspend(mddev); 3550 3551 /* 3552 * Now reshape got set up, update superblocks to 3553 * reflect the fact so that a table reload will 3554 * access proper superblock content in the ctr. 3555 */ 3556 rs_update_sbs(rs); 3557 3558 return 0; 3559 } 3560 3561 static int raid_preresume(struct dm_target *ti) 3562 { 3563 int r; 3564 struct raid_set *rs = ti->private; 3565 struct mddev *mddev = &rs->md; 3566 3567 /* This is a resume after a suspend of the set -> it's already started */ 3568 if (test_and_set_bit(RT_FLAG_RS_PRERESUMED, &rs->runtime_flags)) 3569 return 0; 3570 3571 /* 3572 * The superblocks need to be updated on disk if the 3573 * array is new or new devices got added (thus zeroed 3574 * out by userspace) or __load_dirty_region_bitmap 3575 * will overwrite them in core with old data or fail. 3576 */ 3577 if (test_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags)) 3578 rs_update_sbs(rs); 3579 3580 /* 3581 * Disable/enable discard support on raid set after any 3582 * conversion, because devices can have been added 3583 */ 3584 configure_discard_support(rs); 3585 3586 /* Load the bitmap from disk unless raid0 */ 3587 r = __load_dirty_region_bitmap(rs); 3588 if (r) 3589 return r; 3590 3591 /* Resize bitmap to adjust to changed region size (aka MD bitmap chunksize) */ 3592 if (test_bit(RT_FLAG_RS_BITMAP_LOADED, &rs->runtime_flags) && 3593 mddev->bitmap_info.chunksize != to_bytes(rs->requested_bitmap_chunk_sectors)) { 3594 r = bitmap_resize(mddev->bitmap, mddev->dev_sectors, 3595 to_bytes(rs->requested_bitmap_chunk_sectors), 0); 3596 if (r) 3597 DMERR("Failed to resize bitmap"); 3598 } 3599 3600 /* Check for any resize/reshape on @rs and adjust/initiate */ 3601 /* Be prepared for mddev_resume() in raid_resume() */ 3602 set_bit(MD_RECOVERY_FROZEN, &mddev->recovery); 3603 if (mddev->recovery_cp && mddev->recovery_cp < MaxSector) { 3604 set_bit(MD_RECOVERY_SYNC, &mddev->recovery); 3605 mddev->resync_min = mddev->recovery_cp; 3606 } 3607 3608 rs_set_capacity(rs); 3609 3610 /* Check for any reshape request unless new raid set */ 3611 if (test_and_clear_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags)) { 3612 /* Initiate a reshape. */ 3613 mddev_lock_nointr(mddev); 3614 r = rs_start_reshape(rs); 3615 mddev_unlock(mddev); 3616 if (r) 3617 DMWARN("Failed to check/start reshape, continuing without change"); 3618 r = 0; 3619 } 3620 3621 return r; 3622 } 3623 3624 static void raid_resume(struct dm_target *ti) 3625 { 3626 struct raid_set *rs = ti->private; 3627 struct mddev *mddev = &rs->md; 3628 3629 if (test_and_set_bit(RT_FLAG_RS_RESUMED, &rs->runtime_flags)) { 3630 /* 3631 * A secondary resume while the device is active. 3632 * Take this opportunity to check whether any failed 3633 * devices are reachable again. 3634 */ 3635 attempt_restore_of_faulty_devices(rs); 3636 } 3637 3638 mddev->ro = 0; 3639 mddev->in_sync = 0; 3640 3641 clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery); 3642 3643 if (mddev->suspended) 3644 mddev_resume(mddev); 3645 } 3646 3647 static struct target_type raid_target = { 3648 .name = "raid", 3649 .version = {1, 9, 0}, 3650 .module = THIS_MODULE, 3651 .ctr = raid_ctr, 3652 .dtr = raid_dtr, 3653 .map = raid_map, 3654 .status = raid_status, 3655 .message = raid_message, 3656 .iterate_devices = raid_iterate_devices, 3657 .io_hints = raid_io_hints, 3658 .presuspend = raid_presuspend, 3659 .postsuspend = raid_postsuspend, 3660 .preresume = raid_preresume, 3661 .resume = raid_resume, 3662 }; 3663 3664 static int __init dm_raid_init(void) 3665 { 3666 DMINFO("Loading target version %u.%u.%u", 3667 raid_target.version[0], 3668 raid_target.version[1], 3669 raid_target.version[2]); 3670 return dm_register_target(&raid_target); 3671 } 3672 3673 static void __exit dm_raid_exit(void) 3674 { 3675 dm_unregister_target(&raid_target); 3676 } 3677 3678 module_init(dm_raid_init); 3679 module_exit(dm_raid_exit); 3680 3681 module_param(devices_handle_discard_safely, bool, 0644); 3682 MODULE_PARM_DESC(devices_handle_discard_safely, 3683 "Set to Y if all devices in each array reliably return zeroes on reads from discarded regions"); 3684 3685 MODULE_DESCRIPTION(DM_NAME " raid0/1/10/4/5/6 target"); 3686 MODULE_ALIAS("dm-raid0"); 3687 MODULE_ALIAS("dm-raid1"); 3688 MODULE_ALIAS("dm-raid10"); 3689 MODULE_ALIAS("dm-raid4"); 3690 MODULE_ALIAS("dm-raid5"); 3691 MODULE_ALIAS("dm-raid6"); 3692 MODULE_AUTHOR("Neil Brown <dm-devel@redhat.com>"); 3693 MODULE_AUTHOR("Heinz Mauelshagen <dm-devel@redhat.com>"); 3694 MODULE_LICENSE("GPL"); 3695