drivers/md/dm-raid.c

   1 /*
   2  * Copyright (C) 2010-2011 Neil Brown
   3  * Copyright (C) 2010-2018 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 "md-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 /*
  28  * Minimum journal space 4 MiB in sectors.
  29  */
  30 #define MIN_RAID456_JOURNAL_SPACE (4*2048)
  31
  32 static bool devices_handle_discard_safely = false;
  33
  34 /*
  35  * The following flags are used by dm-raid.c to set up the array state.
  36  * They must be cleared before md_run is called.
  37  */
  38 #define FirstUse 10             /* rdev flag */
  39
  40 struct raid_dev {
  41         /*
  42          * Two DM devices, one to hold metadata and one to hold the
  43          * actual data/parity.  The reason for this is to not confuse
  44          * ti->len and give more flexibility in altering size and
  45          * characteristics.
  46          *
  47          * While it is possible for this device to be associated
  48          * with a different physical device than the data_dev, it
  49          * is intended for it to be the same.
  50          *    |--------- Physical Device ---------|
  51          *    |- meta_dev -|------ data_dev ------|
  52          */
  53         struct dm_dev *meta_dev;
  54         struct dm_dev *data_dev;
  55         struct md_rdev rdev;
  56 };
  57
  58 /*
  59  * Bits for establishing rs->ctr_flags
  60  *
  61  * 1 = no flag value
  62  * 2 = flag with value
  63  */
  64 #define __CTR_FLAG_SYNC                 0  /* 1 */ /* Not with raid0! */
  65 #define __CTR_FLAG_NOSYNC               1  /* 1 */ /* Not with raid0! */
  66 #define __CTR_FLAG_REBUILD              2  /* 2 */ /* Not with raid0! */
  67 #define __CTR_FLAG_DAEMON_SLEEP         3  /* 2 */ /* Not with raid0! */
  68 #define __CTR_FLAG_MIN_RECOVERY_RATE    4  /* 2 */ /* Not with raid0! */
  69 #define __CTR_FLAG_MAX_RECOVERY_RATE    5  /* 2 */ /* Not with raid0! */
  70 #define __CTR_FLAG_MAX_WRITE_BEHIND     6  /* 2 */ /* Only with raid1! */
  71 #define __CTR_FLAG_WRITE_MOSTLY         7  /* 2 */ /* Only with raid1! */
  72 #define __CTR_FLAG_STRIPE_CACHE         8  /* 2 */ /* Only with raid4/5/6! */
  73 #define __CTR_FLAG_REGION_SIZE          9  /* 2 */ /* Not with raid0! */
  74 #define __CTR_FLAG_RAID10_COPIES        10 /* 2 */ /* Only with raid10 */
  75 #define __CTR_FLAG_RAID10_FORMAT        11 /* 2 */ /* Only with raid10 */
  76 /* New for v1.9.0 */
  77 #define __CTR_FLAG_DELTA_DISKS          12 /* 2 */ /* Only with reshapable raid1/4/5/6/10! */
  78 #define __CTR_FLAG_DATA_OFFSET          13 /* 2 */ /* Only with reshapable raid4/5/6/10! */
  79 #define __CTR_FLAG_RAID10_USE_NEAR_SETS 14 /* 2 */ /* Only with raid10! */
  80
  81 /* New for v1.10.0 */
  82 #define __CTR_FLAG_JOURNAL_DEV          15 /* 2 */ /* Only with raid4/5/6 (journal device)! */
  83
  84 /* New for v1.11.1 */
  85 #define __CTR_FLAG_JOURNAL_MODE         16 /* 2 */ /* Only with raid4/5/6 (journal mode)! */
  86
  87 /*
  88  * Flags for rs->ctr_flags field.
  89  */
  90 #define CTR_FLAG_SYNC                   (1 << __CTR_FLAG_SYNC)
  91 #define CTR_FLAG_NOSYNC                 (1 << __CTR_FLAG_NOSYNC)
  92 #define CTR_FLAG_REBUILD                (1 << __CTR_FLAG_REBUILD)
  93 #define CTR_FLAG_DAEMON_SLEEP           (1 << __CTR_FLAG_DAEMON_SLEEP)
  94 #define CTR_FLAG_MIN_RECOVERY_RATE      (1 << __CTR_FLAG_MIN_RECOVERY_RATE)
  95 #define CTR_FLAG_MAX_RECOVERY_RATE      (1 << __CTR_FLAG_MAX_RECOVERY_RATE)
  96 #define CTR_FLAG_MAX_WRITE_BEHIND       (1 << __CTR_FLAG_MAX_WRITE_BEHIND)
  97 #define CTR_FLAG_WRITE_MOSTLY           (1 << __CTR_FLAG_WRITE_MOSTLY)
  98 #define CTR_FLAG_STRIPE_CACHE           (1 << __CTR_FLAG_STRIPE_CACHE)
  99 #define CTR_FLAG_REGION_SIZE            (1 << __CTR_FLAG_REGION_SIZE)
 100 #define CTR_FLAG_RAID10_COPIES          (1 << __CTR_FLAG_RAID10_COPIES)
 101 #define CTR_FLAG_RAID10_FORMAT          (1 << __CTR_FLAG_RAID10_FORMAT)
 102 #define CTR_FLAG_DELTA_DISKS            (1 << __CTR_FLAG_DELTA_DISKS)
 103 #define CTR_FLAG_DATA_OFFSET            (1 << __CTR_FLAG_DATA_OFFSET)
 104 #define CTR_FLAG_RAID10_USE_NEAR_SETS   (1 << __CTR_FLAG_RAID10_USE_NEAR_SETS)
 105 #define CTR_FLAG_JOURNAL_DEV            (1 << __CTR_FLAG_JOURNAL_DEV)
 106 #define CTR_FLAG_JOURNAL_MODE           (1 << __CTR_FLAG_JOURNAL_MODE)
 107
 108 /*
 109  * Definitions of various constructor flags to
 110  * be used in checks of valid / invalid flags
 111  * per raid level.
 112  */
 113 /* Define all any sync flags */
 114 #define CTR_FLAGS_ANY_SYNC              (CTR_FLAG_SYNC | CTR_FLAG_NOSYNC)
 115
 116 /* Define flags for options without argument (e.g. 'nosync') */
 117 #define CTR_FLAG_OPTIONS_NO_ARGS        (CTR_FLAGS_ANY_SYNC | \
 118                                          CTR_FLAG_RAID10_USE_NEAR_SETS)
 119
 120 /* Define flags for options with one argument (e.g. 'delta_disks +2') */
 121 #define CTR_FLAG_OPTIONS_ONE_ARG (CTR_FLAG_REBUILD | \
 122                                   CTR_FLAG_WRITE_MOSTLY | \
 123                                   CTR_FLAG_DAEMON_SLEEP | \
 124                                   CTR_FLAG_MIN_RECOVERY_RATE | \
 125                                   CTR_FLAG_MAX_RECOVERY_RATE | \
 126                                   CTR_FLAG_MAX_WRITE_BEHIND | \
 127                                   CTR_FLAG_STRIPE_CACHE | \
 128                                   CTR_FLAG_REGION_SIZE | \
 129                                   CTR_FLAG_RAID10_COPIES | \
 130                                   CTR_FLAG_RAID10_FORMAT | \
 131                                   CTR_FLAG_DELTA_DISKS | \
 132                                   CTR_FLAG_DATA_OFFSET | \
 133                                   CTR_FLAG_JOURNAL_DEV | \
 134                                   CTR_FLAG_JOURNAL_MODE)
 135
 136 /* Valid options definitions per raid level... */
 137
 138 /* "raid0" does only accept data offset */
 139 #define RAID0_VALID_FLAGS       (CTR_FLAG_DATA_OFFSET)
 140
 141 /* "raid1" does not accept stripe cache, data offset, delta_disks or any raid10 options */
 142 #define RAID1_VALID_FLAGS       (CTR_FLAGS_ANY_SYNC | \
 143                                  CTR_FLAG_REBUILD | \
 144                                  CTR_FLAG_WRITE_MOSTLY | \
 145                                  CTR_FLAG_DAEMON_SLEEP | \
 146                                  CTR_FLAG_MIN_RECOVERY_RATE | \
 147                                  CTR_FLAG_MAX_RECOVERY_RATE | \
 148                                  CTR_FLAG_MAX_WRITE_BEHIND | \
 149                                  CTR_FLAG_REGION_SIZE | \
 150                                  CTR_FLAG_DELTA_DISKS | \
 151                                  CTR_FLAG_DATA_OFFSET)
 152
 153 /* "raid10" does not accept any raid1 or stripe cache options */
 154 #define RAID10_VALID_FLAGS      (CTR_FLAGS_ANY_SYNC | \
 155                                  CTR_FLAG_REBUILD | \
 156                                  CTR_FLAG_DAEMON_SLEEP | \
 157                                  CTR_FLAG_MIN_RECOVERY_RATE | \
 158                                  CTR_FLAG_MAX_RECOVERY_RATE | \
 159                                  CTR_FLAG_REGION_SIZE | \
 160                                  CTR_FLAG_RAID10_COPIES | \
 161                                  CTR_FLAG_RAID10_FORMAT | \
 162                                  CTR_FLAG_DELTA_DISKS | \
 163                                  CTR_FLAG_DATA_OFFSET | \
 164                                  CTR_FLAG_RAID10_USE_NEAR_SETS)
 165
 166 /*
 167  * "raid4/5/6" do not accept any raid1 or raid10 specific options
 168  *
 169  * "raid6" does not accept "nosync", because it is not guaranteed
 170  * that both parity and q-syndrome are being written properly with
 171  * any writes
 172  */
 173 #define RAID45_VALID_FLAGS      (CTR_FLAGS_ANY_SYNC | \
 174                                  CTR_FLAG_REBUILD | \
 175                                  CTR_FLAG_DAEMON_SLEEP | \
 176                                  CTR_FLAG_MIN_RECOVERY_RATE | \
 177                                  CTR_FLAG_MAX_RECOVERY_RATE | \
 178                                  CTR_FLAG_STRIPE_CACHE | \
 179                                  CTR_FLAG_REGION_SIZE | \
 180                                  CTR_FLAG_DELTA_DISKS | \
 181                                  CTR_FLAG_DATA_OFFSET | \
 182                                  CTR_FLAG_JOURNAL_DEV | \
 183                                  CTR_FLAG_JOURNAL_MODE)
 184
 185 #define RAID6_VALID_FLAGS       (CTR_FLAG_SYNC | \
 186                                  CTR_FLAG_REBUILD | \
 187                                  CTR_FLAG_DAEMON_SLEEP | \
 188                                  CTR_FLAG_MIN_RECOVERY_RATE | \
 189                                  CTR_FLAG_MAX_RECOVERY_RATE | \
 190                                  CTR_FLAG_STRIPE_CACHE | \
 191                                  CTR_FLAG_REGION_SIZE | \
 192                                  CTR_FLAG_DELTA_DISKS | \
 193                                  CTR_FLAG_DATA_OFFSET | \
 194                                  CTR_FLAG_JOURNAL_DEV | \
 195                                  CTR_FLAG_JOURNAL_MODE)
 196 /* ...valid options definitions per raid level */
 197
 198 /*
 199  * Flags for rs->runtime_flags field
 200  * (RT_FLAG prefix meaning "runtime flag")
 201  *
 202  * These are all internal and used to define runtime state,
 203  * e.g. to prevent another resume from preresume processing
 204  * the raid set all over again.
 205  */
 206 #define RT_FLAG_RS_PRERESUMED           0
 207 #define RT_FLAG_RS_RESUMED              1
 208 #define RT_FLAG_RS_BITMAP_LOADED        2
 209 #define RT_FLAG_UPDATE_SBS              3
 210 #define RT_FLAG_RESHAPE_RS              4
 211 #define RT_FLAG_RS_SUSPENDED            5
 212 #define RT_FLAG_RS_IN_SYNC              6
 213 #define RT_FLAG_RS_RESYNCING            7
 214 #define RT_FLAG_RS_GROW                 8
 215
 216 /* Array elements of 64 bit needed for rebuild/failed disk bits */
 217 #define DISKS_ARRAY_ELEMS ((MAX_RAID_DEVICES + (sizeof(uint64_t) * 8 - 1)) / sizeof(uint64_t) / 8)
 218
 219 /*
 220  * raid set level, layout and chunk sectors backup/restore
 221  */
 222 struct rs_layout {
 223         int new_level;
 224         int new_layout;
 225         int new_chunk_sectors;
 226 };
 227
 228 struct raid_set {
 229         struct dm_target *ti;
 230
 231         uint32_t stripe_cache_entries;
 232         unsigned long ctr_flags;
 233         unsigned long runtime_flags;
 234
 235         uint64_t rebuild_disks[DISKS_ARRAY_ELEMS];
 236
 237         int raid_disks;
 238         int delta_disks;
 239         int data_offset;
 240         int raid10_copies;
 241         int requested_bitmap_chunk_sectors;
 242
 243         struct mddev md;
 244         struct raid_type *raid_type;
 245
 246         sector_t array_sectors;
 247         sector_t dev_sectors;
 248
 249         /* Optional raid4/5/6 journal device */
 250         struct journal_dev {
 251                 struct dm_dev *dev;
 252                 struct md_rdev rdev;
 253                 int mode;
 254         } journal_dev;
 255
 256         struct raid_dev dev[];
 257 };
 258
 259 static void rs_config_backup(struct raid_set *rs, struct rs_layout *l)
 260 {
 261         struct mddev *mddev = &rs->md;
 262
 263         l->new_level = mddev->new_level;
 264         l->new_layout = mddev->new_layout;
 265         l->new_chunk_sectors = mddev->new_chunk_sectors;
 266 }
 267
 268 static void rs_config_restore(struct raid_set *rs, struct rs_layout *l)
 269 {
 270         struct mddev *mddev = &rs->md;
 271
 272         mddev->new_level = l->new_level;
 273         mddev->new_layout = l->new_layout;
 274         mddev->new_chunk_sectors = l->new_chunk_sectors;
 275 }
 276
 277 /* raid10 algorithms (i.e. formats) */
 278 #define ALGORITHM_RAID10_DEFAULT        0
 279 #define ALGORITHM_RAID10_NEAR           1
 280 #define ALGORITHM_RAID10_OFFSET         2
 281 #define ALGORITHM_RAID10_FAR            3
 282
 283 /* Supported raid types and properties. */
 284 static struct raid_type {
 285         const char *name;               /* RAID algorithm. */
 286         const char *descr;              /* Descriptor text for logging. */
 287         const unsigned int parity_devs; /* # of parity devices. */
 288         const unsigned int minimal_devs;/* minimal # of devices in set. */
 289         const unsigned int level;       /* RAID level. */
 290         const unsigned int algorithm;   /* RAID algorithm. */
 291 } raid_types[] = {
 292         {"raid0",         "raid0 (striping)",                       0, 2, 0,  0 /* NONE */},
 293         {"raid1",         "raid1 (mirroring)",                      0, 2, 1,  0 /* NONE */},
 294         {"raid10_far",    "raid10 far (striped mirrors)",           0, 2, 10, ALGORITHM_RAID10_FAR},
 295         {"raid10_offset", "raid10 offset (striped mirrors)",        0, 2, 10, ALGORITHM_RAID10_OFFSET},
 296         {"raid10_near",   "raid10 near (striped mirrors)",          0, 2, 10, ALGORITHM_RAID10_NEAR},
 297         {"raid10",        "raid10 (striped mirrors)",               0, 2, 10, ALGORITHM_RAID10_DEFAULT},
 298         {"raid4",         "raid4 (dedicated first parity disk)",    1, 2, 5,  ALGORITHM_PARITY_0}, /* raid4 layout = raid5_0 */
 299         {"raid5_n",       "raid5 (dedicated last parity disk)",     1, 2, 5,  ALGORITHM_PARITY_N},
 300         {"raid5_ls",      "raid5 (left symmetric)",                 1, 2, 5,  ALGORITHM_LEFT_SYMMETRIC},
 301         {"raid5_rs",      "raid5 (right symmetric)",                1, 2, 5,  ALGORITHM_RIGHT_SYMMETRIC},
 302         {"raid5_la",      "raid5 (left asymmetric)",                1, 2, 5,  ALGORITHM_LEFT_ASYMMETRIC},
 303         {"raid5_ra",      "raid5 (right asymmetric)",               1, 2, 5,  ALGORITHM_RIGHT_ASYMMETRIC},
 304         {"raid6_zr",      "raid6 (zero restart)",                   2, 4, 6,  ALGORITHM_ROTATING_ZERO_RESTART},
 305         {"raid6_nr",      "raid6 (N restart)",                      2, 4, 6,  ALGORITHM_ROTATING_N_RESTART},
 306         {"raid6_nc",      "raid6 (N continue)",                     2, 4, 6,  ALGORITHM_ROTATING_N_CONTINUE},
 307         {"raid6_n_6",     "raid6 (dedicated parity/Q n/6)",         2, 4, 6,  ALGORITHM_PARITY_N_6},
 308         {"raid6_ls_6",    "raid6 (left symmetric dedicated Q 6)",   2, 4, 6,  ALGORITHM_LEFT_SYMMETRIC_6},
 309         {"raid6_rs_6",    "raid6 (right symmetric dedicated Q 6)",  2, 4, 6,  ALGORITHM_RIGHT_SYMMETRIC_6},
 310         {"raid6_la_6",    "raid6 (left asymmetric dedicated Q 6)",  2, 4, 6,  ALGORITHM_LEFT_ASYMMETRIC_6},
 311         {"raid6_ra_6",    "raid6 (right asymmetric dedicated Q 6)", 2, 4, 6,  ALGORITHM_RIGHT_ASYMMETRIC_6}
 312 };
 313
 314 /* True, if @v is in inclusive range [@min, @max] */
 315 static bool __within_range(long v, long min, long max)
 316 {
 317         return v >= min && v <= max;
 318 }
 319
 320 /* All table line arguments are defined here */
 321 static struct arg_name_flag {
 322         const unsigned long flag;
 323         const char *name;
 324 } __arg_name_flags[] = {
 325         { CTR_FLAG_SYNC, "sync"},
 326         { CTR_FLAG_NOSYNC, "nosync"},
 327         { CTR_FLAG_REBUILD, "rebuild"},
 328         { CTR_FLAG_DAEMON_SLEEP, "daemon_sleep"},
 329         { CTR_FLAG_MIN_RECOVERY_RATE, "min_recovery_rate"},
 330         { CTR_FLAG_MAX_RECOVERY_RATE, "max_recovery_rate"},
 331         { CTR_FLAG_MAX_WRITE_BEHIND, "max_write_behind"},
 332         { CTR_FLAG_WRITE_MOSTLY, "write_mostly"},
 333         { CTR_FLAG_STRIPE_CACHE, "stripe_cache"},
 334         { CTR_FLAG_REGION_SIZE, "region_size"},
 335         { CTR_FLAG_RAID10_COPIES, "raid10_copies"},
 336         { CTR_FLAG_RAID10_FORMAT, "raid10_format"},
 337         { CTR_FLAG_DATA_OFFSET, "data_offset"},
 338         { CTR_FLAG_DELTA_DISKS, "delta_disks"},
 339         { CTR_FLAG_RAID10_USE_NEAR_SETS, "raid10_use_near_sets"},
 340         { CTR_FLAG_JOURNAL_DEV, "journal_dev" },
 341         { CTR_FLAG_JOURNAL_MODE, "journal_mode" },
 342 };
 343
 344 /* Return argument name string for given @flag */
 345 static const char *dm_raid_arg_name_by_flag(const uint32_t flag)
 346 {
 347         if (hweight32(flag) == 1) {
 348                 struct arg_name_flag *anf = __arg_name_flags + ARRAY_SIZE(__arg_name_flags);
 349
 350                 while (anf-- > __arg_name_flags)
 351                         if (flag & anf->flag)
 352                                 return anf->name;
 353
 354         } else
 355                 DMERR("%s called with more than one flag!", __func__);
 356
 357         return NULL;
 358 }
 359
 360 /* Define correlation of raid456 journal cache modes and dm-raid target line parameters */
 361 static struct {
 362         const int mode;
 363         const char *param;
 364 } _raid456_journal_mode[] = {
 365         { R5C_JOURNAL_MODE_WRITE_THROUGH , "writethrough" },
 366         { R5C_JOURNAL_MODE_WRITE_BACK    , "writeback" }
 367 };
 368
 369 /* Return MD raid4/5/6 journal mode for dm @journal_mode one */
 370 static int dm_raid_journal_mode_to_md(const char *mode)
 371 {
 372         int m = ARRAY_SIZE(_raid456_journal_mode);
 373
 374         while (m--)
 375                 if (!strcasecmp(mode, _raid456_journal_mode[m].param))
 376                         return _raid456_journal_mode[m].mode;
 377
 378         return -EINVAL;
 379 }
 380
 381 /* Return dm-raid raid4/5/6 journal mode string for @mode */
 382 static const char *md_journal_mode_to_dm_raid(const int mode)
 383 {
 384         int m = ARRAY_SIZE(_raid456_journal_mode);
 385
 386         while (m--)
 387                 if (mode == _raid456_journal_mode[m].mode)
 388                         return _raid456_journal_mode[m].param;
 389
 390         return "unknown";
 391 }
 392
 393 /*
 394  * Bool helpers to test for various raid levels of a raid set.
 395  * It's level as reported by the superblock rather than
 396  * the requested raid_type passed to the constructor.
 397  */
 398 /* Return true, if raid set in @rs is raid0 */
 399 static bool rs_is_raid0(struct raid_set *rs)
 400 {
 401         return !rs->md.level;
 402 }
 403
 404 /* Return true, if raid set in @rs is raid1 */
 405 static bool rs_is_raid1(struct raid_set *rs)
 406 {
 407         return rs->md.level == 1;
 408 }
 409
 410 /* Return true, if raid set in @rs is raid10 */
 411 static bool rs_is_raid10(struct raid_set *rs)
 412 {
 413         return rs->md.level == 10;
 414 }
 415
 416 /* Return true, if raid set in @rs is level 6 */
 417 static bool rs_is_raid6(struct raid_set *rs)
 418 {
 419         return rs->md.level == 6;
 420 }
 421
 422 /* Return true, if raid set in @rs is level 4, 5 or 6 */
 423 static bool rs_is_raid456(struct raid_set *rs)
 424 {
 425         return __within_range(rs->md.level, 4, 6);
 426 }
 427
 428 /* Return true, if raid set in @rs is reshapable */
 429 static bool __is_raid10_far(int layout);
 430 static bool rs_is_reshapable(struct raid_set *rs)
 431 {
 432         return rs_is_raid456(rs) ||
 433                (rs_is_raid10(rs) && !__is_raid10_far(rs->md.new_layout));
 434 }
 435
 436 /* Return true, if raid set in @rs is recovering */
 437 static bool rs_is_recovering(struct raid_set *rs)
 438 {
 439         return rs->md.recovery_cp < rs->md.dev_sectors;
 440 }
 441
 442 /* Return true, if raid set in @rs is reshaping */
 443 static bool rs_is_reshaping(struct raid_set *rs)
 444 {
 445         return rs->md.reshape_position != MaxSector;
 446 }
 447
 448 /*
 449  * bool helpers to test for various raid levels of a raid type @rt
 450  */
 451
 452 /* Return true, if raid type in @rt is raid0 */
 453 static bool rt_is_raid0(struct raid_type *rt)
 454 {
 455         return !rt->level;
 456 }
 457
 458 /* Return true, if raid type in @rt is raid1 */
 459 static bool rt_is_raid1(struct raid_type *rt)
 460 {
 461         return rt->level == 1;
 462 }
 463
 464 /* Return true, if raid type in @rt is raid10 */
 465 static bool rt_is_raid10(struct raid_type *rt)
 466 {
 467         return rt->level == 10;
 468 }
 469
 470 /* Return true, if raid type in @rt is raid4/5 */
 471 static bool rt_is_raid45(struct raid_type *rt)
 472 {
 473         return __within_range(rt->level, 4, 5);
 474 }
 475
 476 /* Return true, if raid type in @rt is raid6 */
 477 static bool rt_is_raid6(struct raid_type *rt)
 478 {
 479         return rt->level == 6;
 480 }
 481
 482 /* Return true, if raid type in @rt is raid4/5/6 */
 483 static bool rt_is_raid456(struct raid_type *rt)
 484 {
 485         return __within_range(rt->level, 4, 6);
 486 }
 487 /* END: raid level bools */
 488
 489 /* Return valid ctr flags for the raid level of @rs */
 490 static unsigned long __valid_flags(struct raid_set *rs)
 491 {
 492         if (rt_is_raid0(rs->raid_type))
 493                 return RAID0_VALID_FLAGS;
 494         else if (rt_is_raid1(rs->raid_type))
 495                 return RAID1_VALID_FLAGS;
 496         else if (rt_is_raid10(rs->raid_type))
 497                 return RAID10_VALID_FLAGS;
 498         else if (rt_is_raid45(rs->raid_type))
 499                 return RAID45_VALID_FLAGS;
 500         else if (rt_is_raid6(rs->raid_type))
 501                 return RAID6_VALID_FLAGS;
 502
 503         return 0;
 504 }
 505
 506 /*
 507  * Check for valid flags set on @rs
 508  *
 509  * Has to be called after parsing of the ctr flags!
 510  */
 511 static int rs_check_for_valid_flags(struct raid_set *rs)
 512 {
 513         if (rs->ctr_flags & ~__valid_flags(rs)) {
 514                 rs->ti->error = "Invalid flags combination";
 515                 return -EINVAL;
 516         }
 517
 518         return 0;
 519 }
 520
 521 /* MD raid10 bit definitions and helpers */
 522 #define RAID10_OFFSET                   (1 << 16) /* stripes with data copies area adjacent on devices */
 523 #define RAID10_BROCKEN_USE_FAR_SETS     (1 << 17) /* Broken in raid10.c: use sets instead of whole stripe rotation */
 524 #define RAID10_USE_FAR_SETS             (1 << 18) /* Use sets instead of whole stripe rotation */
 525 #define RAID10_FAR_COPIES_SHIFT         8         /* raid10 # far copies shift (2nd byte of layout) */
 526
 527 /* Return md raid10 near copies for @layout */
 528 static unsigned int __raid10_near_copies(int layout)
 529 {
 530         return layout & 0xFF;
 531 }
 532
 533 /* Return md raid10 far copies for @layout */
 534 static unsigned int __raid10_far_copies(int layout)
 535 {
 536         return __raid10_near_copies(layout >> RAID10_FAR_COPIES_SHIFT);
 537 }
 538
 539 /* Return true if md raid10 offset for @layout */
 540 static bool __is_raid10_offset(int layout)
 541 {
 542         return !!(layout & RAID10_OFFSET);
 543 }
 544
 545 /* Return true if md raid10 near for @layout */
 546 static bool __is_raid10_near(int layout)
 547 {
 548         return !__is_raid10_offset(layout) && __raid10_near_copies(layout) > 1;
 549 }
 550
 551 /* Return true if md raid10 far for @layout */
 552 static bool __is_raid10_far(int layout)
 553 {
 554         return !__is_raid10_offset(layout) && __raid10_far_copies(layout) > 1;
 555 }
 556
 557 /* Return md raid10 layout string for @layout */
 558 static const char *raid10_md_layout_to_format(int layout)
 559 {
 560         /*
 561          * Bit 16 stands for "offset"
 562          * (i.e. adjacent stripes hold copies)
 563          *
 564          * Refer to MD's raid10.c for details
 565          */
 566         if (__is_raid10_offset(layout))
 567                 return "offset";
 568
 569         if (__raid10_near_copies(layout) > 1)
 570                 return "near";
 571
 572         if (__raid10_far_copies(layout) > 1)
 573                 return "far";
 574
 575         return "unknown";
 576 }
 577
 578 /* Return md raid10 algorithm for @name */
 579 static int raid10_name_to_format(const char *name)
 580 {
 581         if (!strcasecmp(name, "near"))
 582                 return ALGORITHM_RAID10_NEAR;
 583         else if (!strcasecmp(name, "offset"))
 584                 return ALGORITHM_RAID10_OFFSET;
 585         else if (!strcasecmp(name, "far"))
 586                 return ALGORITHM_RAID10_FAR;
 587
 588         return -EINVAL;
 589 }
 590
 591 /* Return md raid10 copies for @layout */
 592 static unsigned int raid10_md_layout_to_copies(int layout)
 593 {
 594         return max(__raid10_near_copies(layout), __raid10_far_copies(layout));
 595 }
 596
 597 /* Return md raid10 format id for @format string */
 598 static int raid10_format_to_md_layout(struct raid_set *rs,
 599                                       unsigned int algorithm,
 600                                       unsigned int copies)
 601 {
 602         unsigned int n = 1, f = 1, r = 0;
 603
 604         /*
 605          * MD resilienece flaw:
 606          *
 607          * enabling use_far_sets for far/offset formats causes copies
 608          * to be colocated on the same devs together with their origins!
 609          *
 610          * -> disable it for now in the definition above
 611          */
 612         if (algorithm == ALGORITHM_RAID10_DEFAULT ||
 613             algorithm == ALGORITHM_RAID10_NEAR)
 614                 n = copies;
 615
 616         else if (algorithm == ALGORITHM_RAID10_OFFSET) {
 617                 f = copies;
 618                 r = RAID10_OFFSET;
 619                 if (!test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags))
 620                         r |= RAID10_USE_FAR_SETS;
 621
 622         } else if (algorithm == ALGORITHM_RAID10_FAR) {
 623                 f = copies;
 624                 if (!test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags))
 625                         r |= RAID10_USE_FAR_SETS;
 626
 627         } else
 628                 return -EINVAL;
 629
 630         return r | (f << RAID10_FAR_COPIES_SHIFT) | n;
 631 }
 632 /* END: MD raid10 bit definitions and helpers */
 633
 634 /* Check for any of the raid10 algorithms */
 635 static bool __got_raid10(struct raid_type *rtp, const int layout)
 636 {
 637         if (rtp->level == 10) {
 638                 switch (rtp->algorithm) {
 639                 case ALGORITHM_RAID10_DEFAULT:
 640                 case ALGORITHM_RAID10_NEAR:
 641                         return __is_raid10_near(layout);
 642                 case ALGORITHM_RAID10_OFFSET:
 643                         return __is_raid10_offset(layout);
 644                 case ALGORITHM_RAID10_FAR:
 645                         return __is_raid10_far(layout);
 646                 default:
 647                         break;
 648                 }
 649         }
 650
 651         return false;
 652 }
 653
 654 /* Return raid_type for @name */
 655 static struct raid_type *get_raid_type(const char *name)
 656 {
 657         struct raid_type *rtp = raid_types + ARRAY_SIZE(raid_types);
 658
 659         while (rtp-- > raid_types)
 660                 if (!strcasecmp(rtp->name, name))
 661                         return rtp;
 662
 663         return NULL;
 664 }
 665
 666 /* Return raid_type for @name based derived from @level and @layout */
 667 static struct raid_type *get_raid_type_by_ll(const int level, const int layout)
 668 {
 669         struct raid_type *rtp = raid_types + ARRAY_SIZE(raid_types);
 670
 671         while (rtp-- > raid_types) {
 672                 /* RAID10 special checks based on @layout flags/properties */
 673                 if (rtp->level == level &&
 674                     (__got_raid10(rtp, layout) || rtp->algorithm == layout))
 675                         return rtp;
 676         }
 677
 678         return NULL;
 679 }
 680
 681 /* Adjust rdev sectors */
 682 static void rs_set_rdev_sectors(struct raid_set *rs)
 683 {
 684         struct mddev *mddev = &rs->md;
 685         struct md_rdev *rdev;
 686
 687         /*
 688          * raid10 sets rdev->sector to the device size, which
 689          * is unintended in case of out-of-place reshaping
 690          */
 691         rdev_for_each(rdev, mddev)
 692                 if (!test_bit(Journal, &rdev->flags))
 693                         rdev->sectors = mddev->dev_sectors;
 694 }
 695
 696 /*
 697  * Change bdev capacity of @rs in case of a disk add/remove reshape
 698  */
 699 static void rs_set_capacity(struct raid_set *rs)
 700 {
 701         struct gendisk *gendisk = dm_disk(dm_table_get_md(rs->ti->table));
 702
 703         set_capacity_and_notify(gendisk, rs->md.array_sectors);
 704 }
 705
 706 /*
 707  * Set the mddev properties in @rs to the current
 708  * ones retrieved from the freshest superblock
 709  */
 710 static void rs_set_cur(struct raid_set *rs)
 711 {
 712         struct mddev *mddev = &rs->md;
 713
 714         mddev->new_level = mddev->level;
 715         mddev->new_layout = mddev->layout;
 716         mddev->new_chunk_sectors = mddev->chunk_sectors;
 717 }
 718
 719 /*
 720  * Set the mddev properties in @rs to the new
 721  * ones requested by the ctr
 722  */
 723 static void rs_set_new(struct raid_set *rs)
 724 {
 725         struct mddev *mddev = &rs->md;
 726
 727         mddev->level = mddev->new_level;
 728         mddev->layout = mddev->new_layout;
 729         mddev->chunk_sectors = mddev->new_chunk_sectors;
 730         mddev->raid_disks = rs->raid_disks;
 731         mddev->delta_disks = 0;
 732 }
 733
 734 static struct raid_set *raid_set_alloc(struct dm_target *ti, struct raid_type *raid_type,
 735                                        unsigned int raid_devs)
 736 {
 737         unsigned int i;
 738         struct raid_set *rs;
 739
 740         if (raid_devs <= raid_type->parity_devs) {
 741                 ti->error = "Insufficient number of devices";
 742                 return ERR_PTR(-EINVAL);
 743         }
 744
 745         rs = kzalloc(struct_size(rs, dev, raid_devs), GFP_KERNEL);
 746         if (!rs) {
 747                 ti->error = "Cannot allocate raid context";
 748                 return ERR_PTR(-ENOMEM);
 749         }
 750
 751         mddev_init(&rs->md);
 752
 753         rs->raid_disks = raid_devs;
 754         rs->delta_disks = 0;
 755
 756         rs->ti = ti;
 757         rs->raid_type = raid_type;
 758         rs->stripe_cache_entries = 256;
 759         rs->md.raid_disks = raid_devs;
 760         rs->md.level = raid_type->level;
 761         rs->md.new_level = rs->md.level;
 762         rs->md.layout = raid_type->algorithm;
 763         rs->md.new_layout = rs->md.layout;
 764         rs->md.delta_disks = 0;
 765         rs->md.recovery_cp = MaxSector;
 766
 767         for (i = 0; i < raid_devs; i++)
 768                 md_rdev_init(&rs->dev[i].rdev);
 769
 770         /*
 771          * Remaining items to be initialized by further RAID params:
 772          *  rs->md.persistent
 773          *  rs->md.external
 774          *  rs->md.chunk_sectors
 775          *  rs->md.new_chunk_sectors
 776          *  rs->md.dev_sectors
 777          */
 778
 779         return rs;
 780 }
 781
 782 /* Free all @rs allocations */
 783 static void raid_set_free(struct raid_set *rs)
 784 {
 785         int i;
 786
 787         if (rs->journal_dev.dev) {
 788                 md_rdev_clear(&rs->journal_dev.rdev);
 789                 dm_put_device(rs->ti, rs->journal_dev.dev);
 790         }
 791
 792         for (i = 0; i < rs->raid_disks; i++) {
 793                 if (rs->dev[i].meta_dev)
 794                         dm_put_device(rs->ti, rs->dev[i].meta_dev);
 795                 md_rdev_clear(&rs->dev[i].rdev);
 796                 if (rs->dev[i].data_dev)
 797                         dm_put_device(rs->ti, rs->dev[i].data_dev);
 798         }
 799
 800         kfree(rs);
 801 }
 802
 803 /*
 804  * For every device we have two words
 805  *  <meta_dev>: meta device name or '-' if missing
 806  *  <data_dev>: data device name or '-' if missing
 807  *
 808  * The following are permitted:
 809  *    - -
 810  *    - <data_dev>
 811  *    <meta_dev> <data_dev>
 812  *
 813  * The following is not allowed:
 814  *    <meta_dev> -
 815  *
 816  * This code parses those words.  If there is a failure,
 817  * the caller must use raid_set_free() to unwind the operations.
 818  */
 819 static int parse_dev_params(struct raid_set *rs, struct dm_arg_set *as)
 820 {
 821         int i;
 822         int rebuild = 0;
 823         int metadata_available = 0;
 824         int r = 0;
 825         const char *arg;
 826
 827         /* Put off the number of raid devices argument to get to dev pairs */
 828         arg = dm_shift_arg(as);
 829         if (!arg)
 830                 return -EINVAL;
 831
 832         for (i = 0; i < rs->raid_disks; i++) {
 833                 rs->dev[i].rdev.raid_disk = i;
 834
 835                 rs->dev[i].meta_dev = NULL;
 836                 rs->dev[i].data_dev = NULL;
 837
 838                 /*
 839                  * There are no offsets initially.
 840                  * Out of place reshape will set them accordingly.
 841                  */
 842                 rs->dev[i].rdev.data_offset = 0;
 843                 rs->dev[i].rdev.new_data_offset = 0;
 844                 rs->dev[i].rdev.mddev = &rs->md;
 845
 846                 arg = dm_shift_arg(as);
 847                 if (!arg)
 848                         return -EINVAL;
 849
 850                 if (strcmp(arg, "-")) {
 851                         r = dm_get_device(rs->ti, arg, dm_table_get_mode(rs->ti->table),
 852                                           &rs->dev[i].meta_dev);
 853                         if (r) {
 854                                 rs->ti->error = "RAID metadata device lookup failure";
 855                                 return r;
 856                         }
 857
 858                         rs->dev[i].rdev.sb_page = alloc_page(GFP_KERNEL);
 859                         if (!rs->dev[i].rdev.sb_page) {
 860                                 rs->ti->error = "Failed to allocate superblock page";
 861                                 return -ENOMEM;
 862                         }
 863                 }
 864
 865                 arg = dm_shift_arg(as);
 866                 if (!arg)
 867                         return -EINVAL;
 868
 869                 if (!strcmp(arg, "-")) {
 870                         if (!test_bit(In_sync, &rs->dev[i].rdev.flags) &&
 871                             (!rs->dev[i].rdev.recovery_offset)) {
 872                                 rs->ti->error = "Drive designated for rebuild not specified";
 873                                 return -EINVAL;
 874                         }
 875
 876                         if (rs->dev[i].meta_dev) {
 877                                 rs->ti->error = "No data device supplied with metadata device";
 878                                 return -EINVAL;
 879                         }
 880
 881                         continue;
 882                 }
 883
 884                 r = dm_get_device(rs->ti, arg, dm_table_get_mode(rs->ti->table),
 885                                   &rs->dev[i].data_dev);
 886                 if (r) {
 887                         rs->ti->error = "RAID device lookup failure";
 888                         return r;
 889                 }
 890
 891                 if (rs->dev[i].meta_dev) {
 892                         metadata_available = 1;
 893                         rs->dev[i].rdev.meta_bdev = rs->dev[i].meta_dev->bdev;
 894                 }
 895                 rs->dev[i].rdev.bdev = rs->dev[i].data_dev->bdev;
 896                 list_add_tail(&rs->dev[i].rdev.same_set, &rs->md.disks);
 897                 if (!test_bit(In_sync, &rs->dev[i].rdev.flags))
 898                         rebuild++;
 899         }
 900
 901         if (rs->journal_dev.dev)
 902                 list_add_tail(&rs->journal_dev.rdev.same_set, &rs->md.disks);
 903
 904         if (metadata_available) {
 905                 rs->md.external = 0;
 906                 rs->md.persistent = 1;
 907                 rs->md.major_version = 2;
 908         } else if (rebuild && !rs->md.recovery_cp) {
 909                 /*
 910                  * Without metadata, we will not be able to tell if the array
 911                  * is in-sync or not - we must assume it is not.  Therefore,
 912                  * it is impossible to rebuild a drive.
 913                  *
 914                  * Even if there is metadata, the on-disk information may
 915                  * indicate that the array is not in-sync and it will then
 916                  * fail at that time.
 917                  *
 918                  * User could specify 'nosync' option if desperate.
 919                  */
 920                 rs->ti->error = "Unable to rebuild drive while array is not in-sync";
 921                 return -EINVAL;
 922         }
 923
 924         return 0;
 925 }
 926
 927 /*
 928  * validate_region_size
 929  * @rs
 930  * @region_size:  region size in sectors.  If 0, pick a size (4MiB default).
 931  *
 932  * Set rs->md.bitmap_info.chunksize (which really refers to 'region size').
 933  * Ensure that (ti->len/region_size < 2^21) - required by MD bitmap.
 934  *
 935  * Returns: 0 on success, -EINVAL on failure.
 936  */
 937 static int validate_region_size(struct raid_set *rs, unsigned long region_size)
 938 {
 939         unsigned long min_region_size = rs->ti->len / (1 << 21);
 940
 941         if (rs_is_raid0(rs))
 942                 return 0;
 943
 944         if (!region_size) {
 945                 /*
 946                  * Choose a reasonable default.  All figures in sectors.
 947                  */
 948                 if (min_region_size > (1 << 13)) {
 949                         /* If not a power of 2, make it the next power of 2 */
 950                         region_size = roundup_pow_of_two(min_region_size);
 951                         DMINFO("Choosing default region size of %lu sectors",
 952                                region_size);
 953                 } else {
 954                         DMINFO("Choosing default region size of 4MiB");
 955                         region_size = 1 << 13; /* sectors */
 956                 }
 957         } else {
 958                 /*
 959                  * Validate user-supplied value.
 960                  */
 961                 if (region_size > rs->ti->len) {
 962                         rs->ti->error = "Supplied region size is too large";
 963                         return -EINVAL;
 964                 }
 965
 966                 if (region_size < min_region_size) {
 967                         DMERR("Supplied region_size (%lu sectors) below minimum (%lu)",
 968                               region_size, min_region_size);
 969                         rs->ti->error = "Supplied region size is too small";
 970                         return -EINVAL;
 971                 }
 972
 973                 if (!is_power_of_2(region_size)) {
 974                         rs->ti->error = "Region size is not a power of 2";
 975                         return -EINVAL;
 976                 }
 977
 978                 if (region_size < rs->md.chunk_sectors) {
 979                         rs->ti->error = "Region size is smaller than the chunk size";
 980                         return -EINVAL;
 981                 }
 982         }
 983
 984         /*
 985          * Convert sectors to bytes.
 986          */
 987         rs->md.bitmap_info.chunksize = to_bytes(region_size);
 988
 989         return 0;
 990 }
 991
 992 /*
 993  * validate_raid_redundancy
 994  * @rs
 995  *
 996  * Determine if there are enough devices in the array that haven't
 997  * failed (or are being rebuilt) to form a usable array.
 998  *
 999  * Returns: 0 on success, -EINVAL on failure.
1000  */
1001 static int validate_raid_redundancy(struct raid_set *rs)
1002 {
1003         unsigned int i, rebuild_cnt = 0;
1004         unsigned int rebuilds_per_group = 0, copies, raid_disks;
1005         unsigned int group_size, last_group_start;
1006
1007         for (i = 0; i < rs->raid_disks; i++)
1008                 if (!test_bit(FirstUse, &rs->dev[i].rdev.flags) &&
1009                     ((!test_bit(In_sync, &rs->dev[i].rdev.flags) ||
1010                       !rs->dev[i].rdev.sb_page)))
1011                         rebuild_cnt++;
1012
1013         switch (rs->md.level) {
1014         case 0:
1015                 break;
1016         case 1:
1017                 if (rebuild_cnt >= rs->md.raid_disks)
1018                         goto too_many;
1019                 break;
1020         case 4:
1021         case 5:
1022         case 6:
1023                 if (rebuild_cnt > rs->raid_type->parity_devs)
1024                         goto too_many;
1025                 break;
1026         case 10:
1027                 copies = raid10_md_layout_to_copies(rs->md.new_layout);
1028                 if (copies < 2) {
1029                         DMERR("Bogus raid10 data copies < 2!");
1030                         return -EINVAL;
1031                 }
1032
1033                 if (rebuild_cnt < copies)
1034                         break;
1035
1036                 /*
1037                  * It is possible to have a higher rebuild count for RAID10,
1038                  * as long as the failed devices occur in different mirror
1039                  * groups (i.e. different stripes).
1040                  *
1041                  * When checking "near" format, make sure no adjacent devices
1042                  * have failed beyond what can be handled.  In addition to the
1043                  * simple case where the number of devices is a multiple of the
1044                  * number of copies, we must also handle cases where the number
1045                  * of devices is not a multiple of the number of copies.
1046                  * E.g.    dev1 dev2 dev3 dev4 dev5
1047                  *          A    A    B    B    C
1048                  *          C    D    D    E    E
1049                  */
1050                 raid_disks = min(rs->raid_disks, rs->md.raid_disks);
1051                 if (__is_raid10_near(rs->md.new_layout)) {
1052                         for (i = 0; i < raid_disks; i++) {
1053                                 if (!(i % copies))
1054                                         rebuilds_per_group = 0;
1055                                 if ((!rs->dev[i].rdev.sb_page ||
1056                                     !test_bit(In_sync, &rs->dev[i].rdev.flags)) &&
1057                                     (++rebuilds_per_group >= copies))
1058                                         goto too_many;
1059                         }
1060                         break;
1061                 }
1062
1063                 /*
1064                  * When checking "far" and "offset" formats, we need to ensure
1065                  * that the device that holds its copy is not also dead or
1066                  * being rebuilt.  (Note that "far" and "offset" formats only
1067                  * support two copies right now.  These formats also only ever
1068                  * use the 'use_far_sets' variant.)
1069                  *
1070                  * This check is somewhat complicated by the need to account
1071                  * for arrays that are not a multiple of (far) copies.  This
1072                  * results in the need to treat the last (potentially larger)
1073                  * set differently.
1074                  */
1075                 group_size = (raid_disks / copies);
1076                 last_group_start = (raid_disks / group_size) - 1;
1077                 last_group_start *= group_size;
1078                 for (i = 0; i < raid_disks; i++) {
1079                         if (!(i % copies) && !(i > last_group_start))
1080                                 rebuilds_per_group = 0;
1081                         if ((!rs->dev[i].rdev.sb_page ||
1082                              !test_bit(In_sync, &rs->dev[i].rdev.flags)) &&
1083                             (++rebuilds_per_group >= copies))
1084                                         goto too_many;
1085                 }
1086                 break;
1087         default:
1088                 if (rebuild_cnt)
1089                         return -EINVAL;
1090         }
1091
1092         return 0;
1093
1094 too_many:
1095         return -EINVAL;
1096 }
1097
1098 /*
1099  * Possible arguments are...
1100  *      <chunk_size> [optional_args]
1101  *
1102  * Argument definitions
1103  *    <chunk_size>                      The number of sectors per disk that
1104  *                                      will form the "stripe"
1105  *    [[no]sync]                        Force or prevent recovery of the
1106  *                                      entire array
1107  *    [rebuild <idx>]                   Rebuild the drive indicated by the index
1108  *    [daemon_sleep <ms>]               Time between bitmap daemon work to
1109  *                                      clear bits
1110  *    [min_recovery_rate <kB/sec/disk>] Throttle RAID initialization
1111  *    [max_recovery_rate <kB/sec/disk>] Throttle RAID initialization
1112  *    [write_mostly <idx>]              Indicate a write mostly drive via index
1113  *    [max_write_behind <sectors>]      See '-write-behind=' (man mdadm)
1114  *    [stripe_cache <sectors>]          Stripe cache size for higher RAIDs
1115  *    [region_size <sectors>]           Defines granularity of bitmap
1116  *    [journal_dev <dev>]               raid4/5/6 journaling deviice
1117  *                                      (i.e. write hole closing log)
1118  *
1119  * RAID10-only options:
1120  *    [raid10_copies <# copies>]        Number of copies.  (Default: 2)
1121  *    [raid10_format <near|far|offset>] Layout algorithm.  (Default: near)
1122  */
1123 static int parse_raid_params(struct raid_set *rs, struct dm_arg_set *as,
1124                              unsigned int num_raid_params)
1125 {
1126         int value, raid10_format = ALGORITHM_RAID10_DEFAULT;
1127         unsigned int raid10_copies = 2;
1128         unsigned int i, write_mostly = 0;
1129         unsigned int region_size = 0;
1130         sector_t max_io_len;
1131         const char *arg, *key;
1132         struct raid_dev *rd;
1133         struct raid_type *rt = rs->raid_type;
1134
1135         arg = dm_shift_arg(as);
1136         num_raid_params--; /* Account for chunk_size argument */
1137
1138         if (kstrtoint(arg, 10, &value) < 0) {
1139                 rs->ti->error = "Bad numerical argument given for chunk_size";
1140                 return -EINVAL;
1141         }
1142
1143         /*
1144          * First, parse the in-order required arguments
1145          * "chunk_size" is the only argument of this type.
1146          */
1147         if (rt_is_raid1(rt)) {
1148                 if (value)
1149                         DMERR("Ignoring chunk size parameter for RAID 1");
1150                 value = 0;
1151         } else if (!is_power_of_2(value)) {
1152                 rs->ti->error = "Chunk size must be a power of 2";
1153                 return -EINVAL;
1154         } else if (value < 8) {
1155                 rs->ti->error = "Chunk size value is too small";
1156                 return -EINVAL;
1157         }
1158
1159         rs->md.new_chunk_sectors = rs->md.chunk_sectors = value;
1160
1161         /*
1162          * We set each individual device as In_sync with a completed
1163          * 'recovery_offset'.  If there has been a device failure or
1164          * replacement then one of the following cases applies:
1165          *
1166          *   1) User specifies 'rebuild'.
1167          *      - Device is reset when param is read.
1168          *   2) A new device is supplied.
1169          *      - No matching superblock found, resets device.
1170          *   3) Device failure was transient and returns on reload.
1171          *      - Failure noticed, resets device for bitmap replay.
1172          *   4) Device hadn't completed recovery after previous failure.
1173          *      - Superblock is read and overrides recovery_offset.
1174          *
1175          * What is found in the superblocks of the devices is always
1176          * authoritative, unless 'rebuild' or '[no]sync' was specified.
1177          */
1178         for (i = 0; i < rs->raid_disks; i++) {
1179                 set_bit(In_sync, &rs->dev[i].rdev.flags);
1180                 rs->dev[i].rdev.recovery_offset = MaxSector;
1181         }
1182
1183         /*
1184          * Second, parse the unordered optional arguments
1185          */
1186         for (i = 0; i < num_raid_params; i++) {
1187                 key = dm_shift_arg(as);
1188                 if (!key) {
1189                         rs->ti->error = "Not enough raid parameters given";
1190                         return -EINVAL;
1191                 }
1192
1193                 if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_NOSYNC))) {
1194                         if (test_and_set_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) {
1195                                 rs->ti->error = "Only one 'nosync' argument allowed";
1196                                 return -EINVAL;
1197                         }
1198                         continue;
1199                 }
1200                 if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_SYNC))) {
1201                         if (test_and_set_bit(__CTR_FLAG_SYNC, &rs->ctr_flags)) {
1202                                 rs->ti->error = "Only one 'sync' argument allowed";
1203                                 return -EINVAL;
1204                         }
1205                         continue;
1206                 }
1207                 if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_USE_NEAR_SETS))) {
1208                         if (test_and_set_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags)) {
1209                                 rs->ti->error = "Only one 'raid10_use_new_sets' argument allowed";
1210                                 return -EINVAL;
1211                         }
1212                         continue;
1213                 }
1214
1215                 arg = dm_shift_arg(as);
1216                 i++; /* Account for the argument pairs */
1217                 if (!arg) {
1218                         rs->ti->error = "Wrong number of raid parameters given";
1219                         return -EINVAL;
1220                 }
1221
1222                 /*
1223                  * Parameters that take a string value are checked here.
1224                  */
1225                 /* "raid10_format {near|offset|far} */
1226                 if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_FORMAT))) {
1227                         if (test_and_set_bit(__CTR_FLAG_RAID10_FORMAT, &rs->ctr_flags)) {
1228                                 rs->ti->error = "Only one 'raid10_format' argument pair allowed";
1229                                 return -EINVAL;
1230                         }
1231                         if (!rt_is_raid10(rt)) {
1232                                 rs->ti->error = "'raid10_format' is an invalid parameter for this RAID type";
1233                                 return -EINVAL;
1234                         }
1235                         raid10_format = raid10_name_to_format(arg);
1236                         if (raid10_format < 0) {
1237                                 rs->ti->error = "Invalid 'raid10_format' value given";
1238                                 return raid10_format;
1239                         }
1240                         continue;
1241                 }
1242
1243                 /* "journal_dev <dev>" */
1244                 if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_JOURNAL_DEV))) {
1245                         int r;
1246                         struct md_rdev *jdev;
1247
1248                         if (test_and_set_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags)) {
1249                                 rs->ti->error = "Only one raid4/5/6 set journaling device allowed";
1250                                 return -EINVAL;
1251                         }
1252                         if (!rt_is_raid456(rt)) {
1253                                 rs->ti->error = "'journal_dev' is an invalid parameter for this RAID type";
1254                                 return -EINVAL;
1255                         }
1256                         r = dm_get_device(rs->ti, arg, dm_table_get_mode(rs->ti->table),
1257                                           &rs->journal_dev.dev);
1258                         if (r) {
1259                                 rs->ti->error = "raid4/5/6 journal device lookup failure";
1260                                 return r;
1261                         }
1262                         jdev = &rs->journal_dev.rdev;
1263                         md_rdev_init(jdev);
1264                         jdev->mddev = &rs->md;
1265                         jdev->bdev = rs->journal_dev.dev->bdev;
1266                         jdev->sectors = bdev_nr_sectors(jdev->bdev);
1267                         if (jdev->sectors < MIN_RAID456_JOURNAL_SPACE) {
1268                                 rs->ti->error = "No space for raid4/5/6 journal";
1269                                 return -ENOSPC;
1270                         }
1271                         rs->journal_dev.mode = R5C_JOURNAL_MODE_WRITE_THROUGH;
1272                         set_bit(Journal, &jdev->flags);
1273                         continue;
1274                 }
1275
1276                 /* "journal_mode <mode>" ("journal_dev" mandatory!) */
1277                 if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_JOURNAL_MODE))) {
1278                         int r;
1279
1280                         if (!test_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags)) {
1281                                 rs->ti->error = "raid4/5/6 'journal_mode' is invalid without 'journal_dev'";
1282                                 return -EINVAL;
1283                         }
1284                         if (test_and_set_bit(__CTR_FLAG_JOURNAL_MODE, &rs->ctr_flags)) {
1285                                 rs->ti->error = "Only one raid4/5/6 'journal_mode' argument allowed";
1286                                 return -EINVAL;
1287                         }
1288                         r = dm_raid_journal_mode_to_md(arg);
1289                         if (r < 0) {
1290                                 rs->ti->error = "Invalid 'journal_mode' argument";
1291                                 return r;
1292                         }
1293                         rs->journal_dev.mode = r;
1294                         continue;
1295                 }
1296
1297                 /*
1298                  * Parameters with number values from here on.
1299                  */
1300                 if (kstrtoint(arg, 10, &value) < 0) {
1301                         rs->ti->error = "Bad numerical argument given in raid params";
1302                         return -EINVAL;
1303                 }
1304
1305                 if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_REBUILD))) {
1306                         /*
1307                          * "rebuild" is being passed in by userspace to provide
1308                          * indexes of replaced devices and to set up additional
1309                          * devices on raid level takeover.
1310                          */
1311                         if (!__within_range(value, 0, rs->raid_disks - 1)) {
1312                                 rs->ti->error = "Invalid rebuild index given";
1313                                 return -EINVAL;
1314                         }
1315
1316                         if (test_and_set_bit(value, (void *) rs->rebuild_disks)) {
1317                                 rs->ti->error = "rebuild for this index already given";
1318                                 return -EINVAL;
1319                         }
1320
1321                         rd = rs->dev + value;
1322                         clear_bit(In_sync, &rd->rdev.flags);
1323                         clear_bit(Faulty, &rd->rdev.flags);
1324                         rd->rdev.recovery_offset = 0;
1325                         set_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags);
1326                 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_WRITE_MOSTLY))) {
1327                         if (!rt_is_raid1(rt)) {
1328                                 rs->ti->error = "write_mostly option is only valid for RAID1";
1329                                 return -EINVAL;
1330                         }
1331
1332                         if (!__within_range(value, 0, rs->md.raid_disks - 1)) {
1333                                 rs->ti->error = "Invalid write_mostly index given";
1334                                 return -EINVAL;
1335                         }
1336
1337                         write_mostly++;
1338                         set_bit(WriteMostly, &rs->dev[value].rdev.flags);
1339                         set_bit(__CTR_FLAG_WRITE_MOSTLY, &rs->ctr_flags);
1340                 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MAX_WRITE_BEHIND))) {
1341                         if (!rt_is_raid1(rt)) {
1342                                 rs->ti->error = "max_write_behind option is only valid for RAID1";
1343                                 return -EINVAL;
1344                         }
1345
1346                         if (test_and_set_bit(__CTR_FLAG_MAX_WRITE_BEHIND, &rs->ctr_flags)) {
1347                                 rs->ti->error = "Only one max_write_behind argument pair allowed";
1348                                 return -EINVAL;
1349                         }
1350
1351                         /*
1352                          * In device-mapper, we specify things in sectors, but
1353                          * MD records this value in kB
1354                          */
1355                         if (value < 0 || value / 2 > COUNTER_MAX) {
1356                                 rs->ti->error = "Max write-behind limit out of range";
1357                                 return -EINVAL;
1358                         }
1359
1360                         rs->md.bitmap_info.max_write_behind = value / 2;
1361                 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DAEMON_SLEEP))) {
1362                         if (test_and_set_bit(__CTR_FLAG_DAEMON_SLEEP, &rs->ctr_flags)) {
1363                                 rs->ti->error = "Only one daemon_sleep argument pair allowed";
1364                                 return -EINVAL;
1365                         }
1366                         if (value < 0) {
1367                                 rs->ti->error = "daemon sleep period out of range";
1368                                 return -EINVAL;
1369                         }
1370                         rs->md.bitmap_info.daemon_sleep = value;
1371                 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DATA_OFFSET))) {
1372                         /* Userspace passes new data_offset after having extended the data image LV */
1373                         if (test_and_set_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags)) {
1374                                 rs->ti->error = "Only one data_offset argument pair allowed";
1375                                 return -EINVAL;
1376                         }
1377                         /* Ensure sensible data offset */
1378                         if (value < 0 ||
1379                             (value && (value < MIN_FREE_RESHAPE_SPACE || value % to_sector(PAGE_SIZE)))) {
1380                                 rs->ti->error = "Bogus data_offset value";
1381                                 return -EINVAL;
1382                         }
1383                         rs->data_offset = value;
1384                 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_DELTA_DISKS))) {
1385                         /* Define the +/-# of disks to add to/remove from the given raid set */
1386                         if (test_and_set_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags)) {
1387                                 rs->ti->error = "Only one delta_disks argument pair allowed";
1388                                 return -EINVAL;
1389                         }
1390                         /* Ensure MAX_RAID_DEVICES and raid type minimal_devs! */
1391                         if (!__within_range(abs(value), 1, MAX_RAID_DEVICES - rt->minimal_devs)) {
1392                                 rs->ti->error = "Too many delta_disk requested";
1393                                 return -EINVAL;
1394                         }
1395
1396                         rs->delta_disks = value;
1397                 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_STRIPE_CACHE))) {
1398                         if (test_and_set_bit(__CTR_FLAG_STRIPE_CACHE, &rs->ctr_flags)) {
1399                                 rs->ti->error = "Only one stripe_cache argument pair allowed";
1400                                 return -EINVAL;
1401                         }
1402
1403                         if (!rt_is_raid456(rt)) {
1404                                 rs->ti->error = "Inappropriate argument: stripe_cache";
1405                                 return -EINVAL;
1406                         }
1407
1408                         if (value < 0) {
1409                                 rs->ti->error = "Bogus stripe cache entries value";
1410                                 return -EINVAL;
1411                         }
1412                         rs->stripe_cache_entries = value;
1413                 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MIN_RECOVERY_RATE))) {
1414                         if (test_and_set_bit(__CTR_FLAG_MIN_RECOVERY_RATE, &rs->ctr_flags)) {
1415                                 rs->ti->error = "Only one min_recovery_rate argument pair allowed";
1416                                 return -EINVAL;
1417                         }
1418
1419                         if (value < 0) {
1420                                 rs->ti->error = "min_recovery_rate out of range";
1421                                 return -EINVAL;
1422                         }
1423                         rs->md.sync_speed_min = value;
1424                 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_MAX_RECOVERY_RATE))) {
1425                         if (test_and_set_bit(__CTR_FLAG_MAX_RECOVERY_RATE, &rs->ctr_flags)) {
1426                                 rs->ti->error = "Only one max_recovery_rate argument pair allowed";
1427                                 return -EINVAL;
1428                         }
1429
1430                         if (value < 0) {
1431                                 rs->ti->error = "max_recovery_rate out of range";
1432                                 return -EINVAL;
1433                         }
1434                         rs->md.sync_speed_max = value;
1435                 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_REGION_SIZE))) {
1436                         if (test_and_set_bit(__CTR_FLAG_REGION_SIZE, &rs->ctr_flags)) {
1437                                 rs->ti->error = "Only one region_size argument pair allowed";
1438                                 return -EINVAL;
1439                         }
1440
1441                         region_size = value;
1442                         rs->requested_bitmap_chunk_sectors = value;
1443                 } else if (!strcasecmp(key, dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_COPIES))) {
1444                         if (test_and_set_bit(__CTR_FLAG_RAID10_COPIES, &rs->ctr_flags)) {
1445                                 rs->ti->error = "Only one raid10_copies argument pair allowed";
1446                                 return -EINVAL;
1447                         }
1448
1449                         if (!__within_range(value, 2, rs->md.raid_disks)) {
1450                                 rs->ti->error = "Bad value for 'raid10_copies'";
1451                                 return -EINVAL;
1452                         }
1453
1454                         raid10_copies = value;
1455                 } else {
1456                         DMERR("Unable to parse RAID parameter: %s", key);
1457                         rs->ti->error = "Unable to parse RAID parameter";
1458                         return -EINVAL;
1459                 }
1460         }
1461
1462         if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags) &&
1463             test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) {
1464                 rs->ti->error = "sync and nosync are mutually exclusive";
1465                 return -EINVAL;
1466         }
1467
1468         if (test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags) &&
1469             (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags) ||
1470              test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags))) {
1471                 rs->ti->error = "sync/nosync and rebuild are mutually exclusive";
1472                 return -EINVAL;
1473         }
1474
1475         if (write_mostly >= rs->md.raid_disks) {
1476                 rs->ti->error = "Can't set all raid1 devices to write_mostly";
1477                 return -EINVAL;
1478         }
1479
1480         if (rs->md.sync_speed_max &&
1481             rs->md.sync_speed_min > rs->md.sync_speed_max) {
1482                 rs->ti->error = "Bogus recovery rates";
1483                 return -EINVAL;
1484         }
1485
1486         if (validate_region_size(rs, region_size))
1487                 return -EINVAL;
1488
1489         if (rs->md.chunk_sectors)
1490                 max_io_len = rs->md.chunk_sectors;
1491         else
1492                 max_io_len = region_size;
1493
1494         if (dm_set_target_max_io_len(rs->ti, max_io_len))
1495                 return -EINVAL;
1496
1497         if (rt_is_raid10(rt)) {
1498                 if (raid10_copies > rs->md.raid_disks) {
1499                         rs->ti->error = "Not enough devices to satisfy specification";
1500                         return -EINVAL;
1501                 }
1502
1503                 rs->md.new_layout = raid10_format_to_md_layout(rs, raid10_format, raid10_copies);
1504                 if (rs->md.new_layout < 0) {
1505                         rs->ti->error = "Error getting raid10 format";
1506                         return rs->md.new_layout;
1507                 }
1508
1509                 rt = get_raid_type_by_ll(10, rs->md.new_layout);
1510                 if (!rt) {
1511                         rs->ti->error = "Failed to recognize new raid10 layout";
1512                         return -EINVAL;
1513                 }
1514
1515                 if ((rt->algorithm == ALGORITHM_RAID10_DEFAULT ||
1516                      rt->algorithm == ALGORITHM_RAID10_NEAR) &&
1517                     test_bit(__CTR_FLAG_RAID10_USE_NEAR_SETS, &rs->ctr_flags)) {
1518                         rs->ti->error = "RAID10 format 'near' and 'raid10_use_near_sets' are incompatible";
1519                         return -EINVAL;
1520                 }
1521         }
1522
1523         rs->raid10_copies = raid10_copies;
1524
1525         /* Assume there are no metadata devices until the drives are parsed */
1526         rs->md.persistent = 0;
1527         rs->md.external = 1;
1528
1529         /* Check, if any invalid ctr arguments have been passed in for the raid level */
1530         return rs_check_for_valid_flags(rs);
1531 }
1532
1533 /* Set raid4/5/6 cache size */
1534 static int rs_set_raid456_stripe_cache(struct raid_set *rs)
1535 {
1536         int r;
1537         struct r5conf *conf;
1538         struct mddev *mddev = &rs->md;
1539         uint32_t min_stripes = max(mddev->chunk_sectors, mddev->new_chunk_sectors) / 2;
1540         uint32_t nr_stripes = rs->stripe_cache_entries;
1541
1542         if (!rt_is_raid456(rs->raid_type)) {
1543                 rs->ti->error = "Inappropriate raid level; cannot change stripe_cache size";
1544                 return -EINVAL;
1545         }
1546
1547         if (nr_stripes < min_stripes) {
1548                 DMINFO("Adjusting requested %u stripe cache entries to %u to suit stripe size",
1549                        nr_stripes, min_stripes);
1550                 nr_stripes = min_stripes;
1551         }
1552
1553         conf = mddev->private;
1554         if (!conf) {
1555                 rs->ti->error = "Cannot change stripe_cache size on inactive RAID set";
1556                 return -EINVAL;
1557         }
1558
1559         /* Try setting number of stripes in raid456 stripe cache */
1560         if (conf->min_nr_stripes != nr_stripes) {
1561                 r = raid5_set_cache_size(mddev, nr_stripes);
1562                 if (r) {
1563                         rs->ti->error = "Failed to set raid4/5/6 stripe cache size";
1564                         return r;
1565                 }
1566
1567                 DMINFO("%u stripe cache entries", nr_stripes);
1568         }
1569
1570         return 0;
1571 }
1572
1573 /* Return # of data stripes as kept in mddev as of @rs (i.e. as of superblock) */
1574 static unsigned int mddev_data_stripes(struct raid_set *rs)
1575 {
1576         return rs->md.raid_disks - rs->raid_type->parity_devs;
1577 }
1578
1579 /* Return # of data stripes of @rs (i.e. as of ctr) */
1580 static unsigned int rs_data_stripes(struct raid_set *rs)
1581 {
1582         return rs->raid_disks - rs->raid_type->parity_devs;
1583 }
1584
1585 /*
1586  * Retrieve rdev->sectors from any valid raid device of @rs
1587  * to allow userpace to pass in arbitray "- -" device tupples.
1588  */
1589 static sector_t __rdev_sectors(struct raid_set *rs)
1590 {
1591         int i;
1592
1593         for (i = 0; i < rs->raid_disks; i++) {
1594                 struct md_rdev *rdev = &rs->dev[i].rdev;
1595
1596                 if (!test_bit(Journal, &rdev->flags) &&
1597                     rdev->bdev && rdev->sectors)
1598                         return rdev->sectors;
1599         }
1600
1601         return 0;
1602 }
1603
1604 /* Check that calculated dev_sectors fits all component devices. */
1605 static int _check_data_dev_sectors(struct raid_set *rs)
1606 {
1607         sector_t ds = ~0;
1608         struct md_rdev *rdev;
1609
1610         rdev_for_each(rdev, &rs->md)
1611                 if (!test_bit(Journal, &rdev->flags) && rdev->bdev) {
1612                         ds = min(ds, bdev_nr_sectors(rdev->bdev));
1613                         if (ds < rs->md.dev_sectors) {
1614                                 rs->ti->error = "Component device(s) too small";
1615                                 return -EINVAL;
1616                         }
1617                 }
1618
1619         return 0;
1620 }
1621
1622 /* Calculate the sectors per device and per array used for @rs */
1623 static int rs_set_dev_and_array_sectors(struct raid_set *rs, sector_t sectors, bool use_mddev)
1624 {
1625         int delta_disks;
1626         unsigned int data_stripes;
1627         sector_t array_sectors = sectors, dev_sectors = sectors;
1628         struct mddev *mddev = &rs->md;
1629
1630         if (use_mddev) {
1631                 delta_disks = mddev->delta_disks;
1632                 data_stripes = mddev_data_stripes(rs);
1633         } else {
1634                 delta_disks = rs->delta_disks;
1635                 data_stripes = rs_data_stripes(rs);
1636         }
1637
1638         /* Special raid1 case w/o delta_disks support (yet) */
1639         if (rt_is_raid1(rs->raid_type))
1640                 ;
1641         else if (rt_is_raid10(rs->raid_type)) {
1642                 if (rs->raid10_copies < 2 ||
1643                     delta_disks < 0) {
1644                         rs->ti->error = "Bogus raid10 data copies or delta disks";
1645                         return -EINVAL;
1646                 }
1647
1648                 dev_sectors *= rs->raid10_copies;
1649                 if (sector_div(dev_sectors, data_stripes))
1650                         goto bad;
1651
1652                 array_sectors = (data_stripes + delta_disks) * dev_sectors;
1653                 if (sector_div(array_sectors, rs->raid10_copies))
1654                         goto bad;
1655
1656         } else if (sector_div(dev_sectors, data_stripes))
1657                 goto bad;
1658
1659         else
1660                 /* Striped layouts */
1661                 array_sectors = (data_stripes + delta_disks) * dev_sectors;
1662
1663         mddev->array_sectors = array_sectors;
1664         mddev->dev_sectors = dev_sectors;
1665         rs_set_rdev_sectors(rs);
1666
1667         return _check_data_dev_sectors(rs);
1668 bad:
1669         rs->ti->error = "Target length not divisible by number of data devices";
1670         return -EINVAL;
1671 }
1672
1673 /* Setup recovery on @rs */
1674 static void rs_setup_recovery(struct raid_set *rs, sector_t dev_sectors)
1675 {
1676         /* raid0 does not recover */
1677         if (rs_is_raid0(rs))
1678                 rs->md.recovery_cp = MaxSector;
1679         /*
1680          * A raid6 set has to be recovered either
1681          * completely or for the grown part to
1682          * ensure proper parity and Q-Syndrome
1683          */
1684         else if (rs_is_raid6(rs))
1685                 rs->md.recovery_cp = dev_sectors;
1686         /*
1687          * Other raid set types may skip recovery
1688          * depending on the 'nosync' flag.
1689          */
1690         else
1691                 rs->md.recovery_cp = test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)
1692                                      ? MaxSector : dev_sectors;
1693 }
1694
1695 static void do_table_event(struct work_struct *ws)
1696 {
1697         struct raid_set *rs = container_of(ws, struct raid_set, md.event_work);
1698
1699         smp_rmb(); /* Make sure we access most actual mddev properties */
1700         if (!rs_is_reshaping(rs)) {
1701                 if (rs_is_raid10(rs))
1702                         rs_set_rdev_sectors(rs);
1703                 rs_set_capacity(rs);
1704         }
1705         dm_table_event(rs->ti->table);
1706 }
1707
1708 /*
1709  * Make sure a valid takover (level switch) is being requested on @rs
1710  *
1711  * Conversions of raid sets from one MD personality to another
1712  * have to conform to restrictions which are enforced here.
1713  */
1714 static int rs_check_takeover(struct raid_set *rs)
1715 {
1716         struct mddev *mddev = &rs->md;
1717         unsigned int near_copies;
1718
1719         if (rs->md.degraded) {
1720                 rs->ti->error = "Can't takeover degraded raid set";
1721                 return -EPERM;
1722         }
1723
1724         if (rs_is_reshaping(rs)) {
1725                 rs->ti->error = "Can't takeover reshaping raid set";
1726                 return -EPERM;
1727         }
1728
1729         switch (mddev->level) {
1730         case 0:
1731                 /* raid0 -> raid1/5 with one disk */
1732                 if ((mddev->new_level == 1 || mddev->new_level == 5) &&
1733                     mddev->raid_disks == 1)
1734                         return 0;
1735
1736                 /* raid0 -> raid10 */
1737                 if (mddev->new_level == 10 &&
1738                     !(rs->raid_disks % mddev->raid_disks))
1739                         return 0;
1740
1741                 /* raid0 with multiple disks -> raid4/5/6 */
1742                 if (__within_range(mddev->new_level, 4, 6) &&
1743                     mddev->new_layout == ALGORITHM_PARITY_N &&
1744                     mddev->raid_disks > 1)
1745                         return 0;
1746
1747                 break;
1748
1749         case 10:
1750                 /* Can't takeover raid10_offset! */
1751                 if (__is_raid10_offset(mddev->layout))
1752                         break;
1753
1754                 near_copies = __raid10_near_copies(mddev->layout);
1755
1756                 /* raid10* -> raid0 */
1757                 if (mddev->new_level == 0) {
1758                         /* Can takeover raid10_near with raid disks divisable by data copies! */
1759                         if (near_copies > 1 &&
1760                             !(mddev->raid_disks % near_copies)) {
1761                                 mddev->raid_disks /= near_copies;
1762                                 mddev->delta_disks = mddev->raid_disks;
1763                                 return 0;
1764                         }
1765
1766                         /* Can takeover raid10_far */
1767                         if (near_copies == 1 &&
1768                             __raid10_far_copies(mddev->layout) > 1)
1769                                 return 0;
1770
1771                         break;
1772                 }
1773
1774                 /* raid10_{near,far} -> raid1 */
1775                 if (mddev->new_level == 1 &&
1776                     max(near_copies, __raid10_far_copies(mddev->layout)) == mddev->raid_disks)
1777                         return 0;
1778
1779                 /* raid10_{near,far} with 2 disks -> raid4/5 */
1780                 if (__within_range(mddev->new_level, 4, 5) &&
1781                     mddev->raid_disks == 2)
1782                         return 0;
1783                 break;
1784
1785         case 1:
1786                 /* raid1 with 2 disks -> raid4/5 */
1787                 if (__within_range(mddev->new_level, 4, 5) &&
1788                     mddev->raid_disks == 2) {
1789                         mddev->degraded = 1;
1790                         return 0;
1791                 }
1792
1793                 /* raid1 -> raid0 */
1794                 if (mddev->new_level == 0 &&
1795                     mddev->raid_disks == 1)
1796                         return 0;
1797
1798                 /* raid1 -> raid10 */
1799                 if (mddev->new_level == 10)
1800                         return 0;
1801                 break;
1802
1803         case 4:
1804                 /* raid4 -> raid0 */
1805                 if (mddev->new_level == 0)
1806                         return 0;
1807
1808                 /* raid4 -> raid1/5 with 2 disks */
1809                 if ((mddev->new_level == 1 || mddev->new_level == 5) &&
1810                     mddev->raid_disks == 2)
1811                         return 0;
1812
1813                 /* raid4 -> raid5/6 with parity N */
1814                 if (__within_range(mddev->new_level, 5, 6) &&
1815                     mddev->layout == ALGORITHM_PARITY_N)
1816                         return 0;
1817                 break;
1818
1819         case 5:
1820                 /* raid5 with parity N -> raid0 */
1821                 if (mddev->new_level == 0 &&
1822                     mddev->layout == ALGORITHM_PARITY_N)
1823                         return 0;
1824
1825                 /* raid5 with parity N -> raid4 */
1826                 if (mddev->new_level == 4 &&
1827                     mddev->layout == ALGORITHM_PARITY_N)
1828                         return 0;
1829
1830                 /* raid5 with 2 disks -> raid1/4/10 */
1831                 if ((mddev->new_level == 1 || mddev->new_level == 4 || mddev->new_level == 10) &&
1832                     mddev->raid_disks == 2)
1833                         return 0;
1834
1835                 /* raid5_* ->  raid6_*_6 with Q-Syndrome N (e.g. raid5_ra -> raid6_ra_6 */
1836                 if (mddev->new_level == 6 &&
1837                     ((mddev->layout == ALGORITHM_PARITY_N && mddev->new_layout == ALGORITHM_PARITY_N) ||
1838                       __within_range(mddev->new_layout, ALGORITHM_LEFT_ASYMMETRIC_6, ALGORITHM_RIGHT_SYMMETRIC_6)))
1839                         return 0;
1840                 break;
1841
1842         case 6:
1843                 /* raid6 with parity N -> raid0 */
1844                 if (mddev->new_level == 0 &&
1845                     mddev->layout == ALGORITHM_PARITY_N)
1846                         return 0;
1847
1848                 /* raid6 with parity N -> raid4 */
1849                 if (mddev->new_level == 4 &&
1850                     mddev->layout == ALGORITHM_PARITY_N)
1851                         return 0;
1852
1853                 /* raid6_*_n with Q-Syndrome N -> raid5_* */
1854                 if (mddev->new_level == 5 &&
1855                     ((mddev->layout == ALGORITHM_PARITY_N && mddev->new_layout == ALGORITHM_PARITY_N) ||
1856                      __within_range(mddev->new_layout, ALGORITHM_LEFT_ASYMMETRIC, ALGORITHM_RIGHT_SYMMETRIC)))
1857                         return 0;
1858                 break;
1859
1860         default:
1861                 break;
1862         }
1863
1864         rs->ti->error = "takeover not possible";
1865         return -EINVAL;
1866 }
1867
1868 /* True if @rs requested to be taken over */
1869 static bool rs_takeover_requested(struct raid_set *rs)
1870 {
1871         return rs->md.new_level != rs->md.level;
1872 }
1873
1874 /* True if layout is set to reshape. */
1875 static bool rs_is_layout_change(struct raid_set *rs, bool use_mddev)
1876 {
1877         return (use_mddev ? rs->md.delta_disks : rs->delta_disks) ||
1878                rs->md.new_layout != rs->md.layout ||
1879                rs->md.new_chunk_sectors != rs->md.chunk_sectors;
1880 }
1881
1882 /* True if @rs is requested to reshape by ctr */
1883 static bool rs_reshape_requested(struct raid_set *rs)
1884 {
1885         bool change;
1886         struct mddev *mddev = &rs->md;
1887
1888         if (rs_takeover_requested(rs))
1889                 return false;
1890
1891         if (rs_is_raid0(rs))
1892                 return false;
1893
1894         change = rs_is_layout_change(rs, false);
1895
1896         /* Historical case to support raid1 reshape without delta disks */
1897         if (rs_is_raid1(rs)) {
1898                 if (rs->delta_disks)
1899                         return !!rs->delta_disks;
1900
1901                 return !change &&
1902                        mddev->raid_disks != rs->raid_disks;
1903         }
1904
1905         if (rs_is_raid10(rs))
1906                 return change &&
1907                        !__is_raid10_far(mddev->new_layout) &&
1908                        rs->delta_disks >= 0;
1909
1910         return change;
1911 }
1912
1913 /*  Features */
1914 #define FEATURE_FLAG_SUPPORTS_V190      0x1 /* Supports extended superblock */
1915
1916 /* State flags for sb->flags */
1917 #define SB_FLAG_RESHAPE_ACTIVE          0x1
1918 #define SB_FLAG_RESHAPE_BACKWARDS       0x2
1919
1920 /*
1921  * This structure is never routinely used by userspace, unlike md superblocks.
1922  * Devices with this superblock should only ever be accessed via device-mapper.
1923  */
1924 #define DM_RAID_MAGIC 0x64526D44
1925 struct dm_raid_superblock {
1926         __le32 magic;           /* "DmRd" */
1927         __le32 compat_features; /* Used to indicate compatible features (like 1.9.0 ondisk metadata extension) */
1928
1929         __le32 num_devices;     /* Number of devices in this raid set. (Max 64) */
1930         __le32 array_position;  /* The position of this drive in the raid set */
1931
1932         __le64 events;          /* Incremented by md when superblock updated */
1933         __le64 failed_devices;  /* Pre 1.9.0 part of bit field of devices to */
1934                                 /* indicate failures (see extension below) */
1935
1936         /*
1937          * This offset tracks the progress of the repair or replacement of
1938          * an individual drive.
1939          */
1940         __le64 disk_recovery_offset;
1941
1942         /*
1943          * This offset tracks the progress of the initial raid set
1944          * synchronisation/parity calculation.
1945          */
1946         __le64 array_resync_offset;
1947
1948         /*
1949          * raid characteristics
1950          */
1951         __le32 level;
1952         __le32 layout;
1953         __le32 stripe_sectors;
1954
1955         /********************************************************************
1956          * BELOW FOLLOW V1.9.0 EXTENSIONS TO THE PRISTINE SUPERBLOCK FORMAT!!!
1957          *
1958          * FEATURE_FLAG_SUPPORTS_V190 in the compat_features member indicates that those exist
1959          */
1960
1961         __le32 flags; /* Flags defining array states for reshaping */
1962
1963         /*
1964          * This offset tracks the progress of a raid
1965          * set reshape in order to be able to restart it
1966          */
1967         __le64 reshape_position;
1968
1969         /*
1970          * These define the properties of the array in case of an interrupted reshape
1971          */
1972         __le32 new_level;
1973         __le32 new_layout;
1974         __le32 new_stripe_sectors;
1975         __le32 delta_disks;
1976
1977         __le64 array_sectors; /* Array size in sectors */
1978
1979         /*
1980          * Sector offsets to data on devices (reshaping).
1981          * Needed to support out of place reshaping, thus
1982          * not writing over any stripes whilst converting
1983          * them from old to new layout
1984          */
1985         __le64 data_offset;
1986         __le64 new_data_offset;
1987
1988         __le64 sectors; /* Used device size in sectors */
1989
1990         /*
1991          * Additonal Bit field of devices indicating failures to support
1992          * up to 256 devices with the 1.9.0 on-disk metadata format
1993          */
1994         __le64 extended_failed_devices[DISKS_ARRAY_ELEMS - 1];
1995
1996         __le32 incompat_features;       /* Used to indicate any incompatible features */
1997
1998         /* Always set rest up to logical block size to 0 when writing (see get_metadata_device() below). */
1999 } __packed;
2000
2001 /*
2002  * Check for reshape constraints on raid set @rs:
2003  *
2004  * - reshape function non-existent
2005  * - degraded set
2006  * - ongoing recovery
2007  * - ongoing reshape
2008  *
2009  * Returns 0 if none or -EPERM if given constraint
2010  * and error message reference in @errmsg
2011  */
2012 static int rs_check_reshape(struct raid_set *rs)
2013 {
2014         struct mddev *mddev = &rs->md;
2015
2016         if (!mddev->pers || !mddev->pers->check_reshape)
2017                 rs->ti->error = "Reshape not supported";
2018         else if (mddev->degraded)
2019                 rs->ti->error = "Can't reshape degraded raid set";
2020         else if (rs_is_recovering(rs))
2021                 rs->ti->error = "Convert request on recovering raid set prohibited";
2022         else if (rs_is_reshaping(rs))
2023                 rs->ti->error = "raid set already reshaping!";
2024         else if (!(rs_is_raid1(rs) || rs_is_raid10(rs) || rs_is_raid456(rs)))
2025                 rs->ti->error = "Reshaping only supported for raid1/4/5/6/10";
2026         else
2027                 return 0;
2028
2029         return -EPERM;
2030 }
2031
2032 static int read_disk_sb(struct md_rdev *rdev, int size, bool force_reload)
2033 {
2034         BUG_ON(!rdev->sb_page);
2035
2036         if (rdev->sb_loaded && !force_reload)
2037                 return 0;
2038
2039         rdev->sb_loaded = 0;
2040
2041         if (!sync_page_io(rdev, 0, size, rdev->sb_page, REQ_OP_READ, true)) {
2042                 DMERR("Failed to read superblock of device at position %d",
2043                       rdev->raid_disk);
2044                 md_error(rdev->mddev, rdev);
2045                 set_bit(Faulty, &rdev->flags);
2046                 return -EIO;
2047         }
2048
2049         rdev->sb_loaded = 1;
2050
2051         return 0;
2052 }
2053
2054 static void sb_retrieve_failed_devices(struct dm_raid_superblock *sb, uint64_t *failed_devices)
2055 {
2056         failed_devices[0] = le64_to_cpu(sb->failed_devices);
2057         memset(failed_devices + 1, 0, sizeof(sb->extended_failed_devices));
2058
2059         if (le32_to_cpu(sb->compat_features) & FEATURE_FLAG_SUPPORTS_V190) {
2060                 int i = ARRAY_SIZE(sb->extended_failed_devices);
2061
2062                 while (i--)
2063                         failed_devices[i+1] = le64_to_cpu(sb->extended_failed_devices[i]);
2064         }
2065 }
2066
2067 static void sb_update_failed_devices(struct dm_raid_superblock *sb, uint64_t *failed_devices)
2068 {
2069         int i = ARRAY_SIZE(sb->extended_failed_devices);
2070
2071         sb->failed_devices = cpu_to_le64(failed_devices[0]);
2072         while (i--)
2073                 sb->extended_failed_devices[i] = cpu_to_le64(failed_devices[i+1]);
2074 }
2075
2076 /*
2077  * Synchronize the superblock members with the raid set properties
2078  *
2079  * All superblock data is little endian.
2080  */
2081 static void super_sync(struct mddev *mddev, struct md_rdev *rdev)
2082 {
2083         bool update_failed_devices = false;
2084         unsigned int i;
2085         uint64_t failed_devices[DISKS_ARRAY_ELEMS];
2086         struct dm_raid_superblock *sb;
2087         struct raid_set *rs = container_of(mddev, struct raid_set, md);
2088
2089         /* No metadata device, no superblock */
2090         if (!rdev->meta_bdev)
2091                 return;
2092
2093         BUG_ON(!rdev->sb_page);
2094
2095         sb = page_address(rdev->sb_page);
2096
2097         sb_retrieve_failed_devices(sb, failed_devices);
2098
2099         for (i = 0; i < rs->raid_disks; i++)
2100                 if (!rs->dev[i].data_dev || test_bit(Faulty, &rs->dev[i].rdev.flags)) {
2101                         update_failed_devices = true;
2102                         set_bit(i, (void *) failed_devices);
2103                 }
2104
2105         if (update_failed_devices)
2106                 sb_update_failed_devices(sb, failed_devices);
2107
2108         sb->magic = cpu_to_le32(DM_RAID_MAGIC);
2109         sb->compat_features = cpu_to_le32(FEATURE_FLAG_SUPPORTS_V190);
2110
2111         sb->num_devices = cpu_to_le32(mddev->raid_disks);
2112         sb->array_position = cpu_to_le32(rdev->raid_disk);
2113
2114         sb->events = cpu_to_le64(mddev->events);
2115
2116         sb->disk_recovery_offset = cpu_to_le64(rdev->recovery_offset);
2117         sb->array_resync_offset = cpu_to_le64(mddev->recovery_cp);
2118
2119         sb->level = cpu_to_le32(mddev->level);
2120         sb->layout = cpu_to_le32(mddev->layout);
2121         sb->stripe_sectors = cpu_to_le32(mddev->chunk_sectors);
2122
2123         /********************************************************************
2124          * BELOW FOLLOW V1.9.0 EXTENSIONS TO THE PRISTINE SUPERBLOCK FORMAT!!!
2125          *
2126          * FEATURE_FLAG_SUPPORTS_V190 in the compat_features member indicates that those exist
2127          */
2128         sb->new_level = cpu_to_le32(mddev->new_level);
2129         sb->new_layout = cpu_to_le32(mddev->new_layout);
2130         sb->new_stripe_sectors = cpu_to_le32(mddev->new_chunk_sectors);
2131
2132         sb->delta_disks = cpu_to_le32(mddev->delta_disks);
2133
2134         smp_rmb(); /* Make sure we access most recent reshape position */
2135         sb->reshape_position = cpu_to_le64(mddev->reshape_position);
2136         if (le64_to_cpu(sb->reshape_position) != MaxSector) {
2137                 /* Flag ongoing reshape */
2138                 sb->flags |= cpu_to_le32(SB_FLAG_RESHAPE_ACTIVE);
2139
2140                 if (mddev->delta_disks < 0 || mddev->reshape_backwards)
2141                         sb->flags |= cpu_to_le32(SB_FLAG_RESHAPE_BACKWARDS);
2142         } else {
2143                 /* Clear reshape flags */
2144                 sb->flags &= ~(cpu_to_le32(SB_FLAG_RESHAPE_ACTIVE|SB_FLAG_RESHAPE_BACKWARDS));
2145         }
2146
2147         sb->array_sectors = cpu_to_le64(mddev->array_sectors);
2148         sb->data_offset = cpu_to_le64(rdev->data_offset);
2149         sb->new_data_offset = cpu_to_le64(rdev->new_data_offset);
2150         sb->sectors = cpu_to_le64(rdev->sectors);
2151         sb->incompat_features = cpu_to_le32(0);
2152
2153         /* Zero out the rest of the payload after the size of the superblock */
2154         memset(sb + 1, 0, rdev->sb_size - sizeof(*sb));
2155 }
2156
2157 /*
2158  * super_load
2159  *
2160  * This function creates a superblock if one is not found on the device
2161  * and will decide which superblock to use if there's a choice.
2162  *
2163  * Return: 1 if use rdev, 0 if use refdev, -Exxx otherwise
2164  */
2165 static int super_load(struct md_rdev *rdev, struct md_rdev *refdev)
2166 {
2167         int r;
2168         struct dm_raid_superblock *sb;
2169         struct dm_raid_superblock *refsb;
2170         uint64_t events_sb, events_refsb;
2171
2172         r = read_disk_sb(rdev, rdev->sb_size, false);
2173         if (r)
2174                 return r;
2175
2176         sb = page_address(rdev->sb_page);
2177
2178         /*
2179          * Two cases that we want to write new superblocks and rebuild:
2180          * 1) New device (no matching magic number)
2181          * 2) Device specified for rebuild (!In_sync w/ offset == 0)
2182          */
2183         if ((sb->magic != cpu_to_le32(DM_RAID_MAGIC)) ||
2184             (!test_bit(In_sync, &rdev->flags) && !rdev->recovery_offset)) {
2185                 super_sync(rdev->mddev, rdev);
2186
2187                 set_bit(FirstUse, &rdev->flags);
2188                 sb->compat_features = cpu_to_le32(FEATURE_FLAG_SUPPORTS_V190);
2189
2190                 /* Force writing of superblocks to disk */
2191                 set_bit(MD_SB_CHANGE_DEVS, &rdev->mddev->sb_flags);
2192
2193                 /* Any superblock is better than none, choose that if given */
2194                 return refdev ? 0 : 1;
2195         }
2196
2197         if (!refdev)
2198                 return 1;
2199
2200         events_sb = le64_to_cpu(sb->events);
2201
2202         refsb = page_address(refdev->sb_page);
2203         events_refsb = le64_to_cpu(refsb->events);
2204
2205         return (events_sb > events_refsb) ? 1 : 0;
2206 }
2207
2208 static int super_init_validation(struct raid_set *rs, struct md_rdev *rdev)
2209 {
2210         int role;
2211         unsigned int d;
2212         struct mddev *mddev = &rs->md;
2213         uint64_t events_sb;
2214         uint64_t failed_devices[DISKS_ARRAY_ELEMS];
2215         struct dm_raid_superblock *sb;
2216         uint32_t new_devs = 0, rebuild_and_new = 0, rebuilds = 0;
2217         struct md_rdev *r;
2218         struct dm_raid_superblock *sb2;
2219
2220         sb = page_address(rdev->sb_page);
2221         events_sb = le64_to_cpu(sb->events);
2222
2223         /*
2224          * Initialise to 1 if this is a new superblock.
2225          */
2226         mddev->events = events_sb ? : 1;
2227
2228         mddev->reshape_position = MaxSector;
2229
2230         mddev->raid_disks = le32_to_cpu(sb->num_devices);
2231         mddev->level = le32_to_cpu(sb->level);
2232         mddev->layout = le32_to_cpu(sb->layout);
2233         mddev->chunk_sectors = le32_to_cpu(sb->stripe_sectors);
2234
2235         /*
2236          * Reshaping is supported, e.g. reshape_position is valid
2237          * in superblock and superblock content is authoritative.
2238          */
2239         if (le32_to_cpu(sb->compat_features) & FEATURE_FLAG_SUPPORTS_V190) {
2240                 /* Superblock is authoritative wrt given raid set layout! */
2241                 mddev->new_level = le32_to_cpu(sb->new_level);
2242                 mddev->new_layout = le32_to_cpu(sb->new_layout);
2243                 mddev->new_chunk_sectors = le32_to_cpu(sb->new_stripe_sectors);
2244                 mddev->delta_disks = le32_to_cpu(sb->delta_disks);
2245                 mddev->array_sectors = le64_to_cpu(sb->array_sectors);
2246
2247                 /* raid was reshaping and got interrupted */
2248                 if (le32_to_cpu(sb->flags) & SB_FLAG_RESHAPE_ACTIVE) {
2249                         if (test_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags)) {
2250                                 DMERR("Reshape requested but raid set is still reshaping");
2251                                 return -EINVAL;
2252                         }
2253
2254                         if (mddev->delta_disks < 0 ||
2255                             (!mddev->delta_disks && (le32_to_cpu(sb->flags) & SB_FLAG_RESHAPE_BACKWARDS)))
2256                                 mddev->reshape_backwards = 1;
2257                         else
2258                                 mddev->reshape_backwards = 0;
2259
2260                         mddev->reshape_position = le64_to_cpu(sb->reshape_position);
2261                         rs->raid_type = get_raid_type_by_ll(mddev->level, mddev->layout);
2262                 }
2263
2264         } else {
2265                 /*
2266                  * No takeover/reshaping, because we don't have the extended v1.9.0 metadata
2267                  */
2268                 struct raid_type *rt_cur = get_raid_type_by_ll(mddev->level, mddev->layout);
2269                 struct raid_type *rt_new = get_raid_type_by_ll(mddev->new_level, mddev->new_layout);
2270
2271                 if (rs_takeover_requested(rs)) {
2272                         if (rt_cur && rt_new)
2273                                 DMERR("Takeover raid sets from %s to %s not yet supported by metadata. (raid level change)",
2274                                       rt_cur->name, rt_new->name);
2275                         else
2276                                 DMERR("Takeover raid sets not yet supported by metadata. (raid level change)");
2277                         return -EINVAL;
2278                 } else if (rs_reshape_requested(rs)) {
2279                         DMERR("Reshaping raid sets not yet supported by metadata. (raid layout change keeping level)");
2280                         if (mddev->layout != mddev->new_layout) {
2281                                 if (rt_cur && rt_new)
2282                                         DMERR("  current layout %s vs new layout %s",
2283                                               rt_cur->name, rt_new->name);
2284                                 else
2285                                         DMERR("  current layout 0x%X vs new layout 0x%X",
2286                                               le32_to_cpu(sb->layout), mddev->new_layout);
2287                         }
2288                         if (mddev->chunk_sectors != mddev->new_chunk_sectors)
2289                                 DMERR("  current stripe sectors %u vs new stripe sectors %u",
2290                                       mddev->chunk_sectors, mddev->new_chunk_sectors);
2291                         if (rs->delta_disks)
2292                                 DMERR("  current %u disks vs new %u disks",
2293                                       mddev->raid_disks, mddev->raid_disks + rs->delta_disks);
2294                         if (rs_is_raid10(rs)) {
2295                                 DMERR("  Old layout: %s w/ %u copies",
2296                                       raid10_md_layout_to_format(mddev->layout),
2297                                       raid10_md_layout_to_copies(mddev->layout));
2298                                 DMERR("  New layout: %s w/ %u copies",
2299                                       raid10_md_layout_to_format(mddev->new_layout),
2300                                       raid10_md_layout_to_copies(mddev->new_layout));
2301                         }
2302                         return -EINVAL;
2303                 }
2304
2305                 DMINFO("Discovered old metadata format; upgrading to extended metadata format");
2306         }
2307
2308         if (!test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags))
2309                 mddev->recovery_cp = le64_to_cpu(sb->array_resync_offset);
2310
2311         /*
2312          * During load, we set FirstUse if a new superblock was written.
2313          * There are two reasons we might not have a superblock:
2314          * 1) The raid set is brand new - in which case, all of the
2315          *    devices must have their In_sync bit set.  Also,
2316          *    recovery_cp must be 0, unless forced.
2317          * 2) This is a new device being added to an old raid set
2318          *    and the new device needs to be rebuilt - in which
2319          *    case the In_sync bit will /not/ be set and
2320          *    recovery_cp must be MaxSector.
2321          * 3) This is/are a new device(s) being added to an old
2322          *    raid set during takeover to a higher raid level
2323          *    to provide capacity for redundancy or during reshape
2324          *    to add capacity to grow the raid set.
2325          */
2326         d = 0;
2327         rdev_for_each(r, mddev) {
2328                 if (test_bit(Journal, &rdev->flags))
2329                         continue;
2330
2331                 if (test_bit(FirstUse, &r->flags))
2332                         new_devs++;
2333
2334                 if (!test_bit(In_sync, &r->flags)) {
2335                         DMINFO("Device %d specified for rebuild; clearing superblock",
2336                                 r->raid_disk);
2337                         rebuilds++;
2338
2339                         if (test_bit(FirstUse, &r->flags))
2340                                 rebuild_and_new++;
2341                 }
2342
2343                 d++;
2344         }
2345
2346         if (new_devs == rs->raid_disks || !rebuilds) {
2347                 /* Replace a broken device */
2348                 if (new_devs == rs->raid_disks) {
2349                         DMINFO("Superblocks created for new raid set");
2350                         set_bit(MD_ARRAY_FIRST_USE, &mddev->flags);
2351                 } else if (new_devs != rebuilds &&
2352                            new_devs != rs->delta_disks) {
2353                         DMERR("New device injected into existing raid set without "
2354                               "'delta_disks' or 'rebuild' parameter specified");
2355                         return -EINVAL;
2356                 }
2357         } else if (new_devs && new_devs != rebuilds) {
2358                 DMERR("%u 'rebuild' devices cannot be injected into"
2359                       " a raid set with %u other first-time devices",
2360                       rebuilds, new_devs);
2361                 return -EINVAL;
2362         } else if (rebuilds) {
2363                 if (rebuild_and_new && rebuilds != rebuild_and_new) {
2364                         DMERR("new device%s provided without 'rebuild'",
2365                               new_devs > 1 ? "s" : "");
2366                         return -EINVAL;
2367                 } else if (!test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags) && rs_is_recovering(rs)) {
2368                         DMERR("'rebuild' specified while raid set is not in-sync (recovery_cp=%llu)",
2369                               (unsigned long long) mddev->recovery_cp);
2370                         return -EINVAL;
2371                 } else if (rs_is_reshaping(rs)) {
2372                         DMERR("'rebuild' specified while raid set is being reshaped (reshape_position=%llu)",
2373                               (unsigned long long) mddev->reshape_position);
2374                         return -EINVAL;
2375                 }
2376         }
2377
2378         /*
2379          * Now we set the Faulty bit for those devices that are
2380          * recorded in the superblock as failed.
2381          */
2382         sb_retrieve_failed_devices(sb, failed_devices);
2383         rdev_for_each(r, mddev) {
2384                 if (test_bit(Journal, &rdev->flags) ||
2385                     !r->sb_page)
2386                         continue;
2387                 sb2 = page_address(r->sb_page);
2388                 sb2->failed_devices = 0;
2389                 memset(sb2->extended_failed_devices, 0, sizeof(sb2->extended_failed_devices));
2390
2391                 /*
2392                  * Check for any device re-ordering.
2393                  */
2394                 if (!test_bit(FirstUse, &r->flags) && (r->raid_disk >= 0)) {
2395                         role = le32_to_cpu(sb2->array_position);
2396                         if (role < 0)
2397                                 continue;
2398
2399                         if (role != r->raid_disk) {
2400                                 if (rs_is_raid10(rs) && __is_raid10_near(mddev->layout)) {
2401                                         if (mddev->raid_disks % __raid10_near_copies(mddev->layout) ||
2402                                             rs->raid_disks % rs->raid10_copies) {
2403                                                 rs->ti->error =
2404                                                         "Cannot change raid10 near set to odd # of devices!";
2405                                                 return -EINVAL;
2406                                         }
2407
2408                                         sb2->array_position = cpu_to_le32(r->raid_disk);
2409
2410                                 } else if (!(rs_is_raid10(rs) && rt_is_raid0(rs->raid_type)) &&
2411                                            !(rs_is_raid0(rs) && rt_is_raid10(rs->raid_type)) &&
2412                                            !rt_is_raid1(rs->raid_type)) {
2413                                         rs->ti->error = "Cannot change device positions in raid set";
2414                                         return -EINVAL;
2415                                 }
2416
2417                                 DMINFO("raid device #%d now at position #%d", role, r->raid_disk);
2418                         }
2419
2420                         /*
2421                          * Partial recovery is performed on
2422                          * returning failed devices.
2423                          */
2424                         if (test_bit(role, (void *) failed_devices))
2425                                 set_bit(Faulty, &r->flags);
2426                 }
2427         }
2428
2429         return 0;
2430 }
2431
2432 static int super_validate(struct raid_set *rs, struct md_rdev *rdev)
2433 {
2434         struct mddev *mddev = &rs->md;
2435         struct dm_raid_superblock *sb;
2436
2437         if (rs_is_raid0(rs) || !rdev->sb_page || rdev->raid_disk < 0)
2438                 return 0;
2439
2440         sb = page_address(rdev->sb_page);
2441
2442         /*
2443          * If mddev->events is not set, we know we have not yet initialized
2444          * the array.
2445          */
2446         if (!mddev->events && super_init_validation(rs, rdev))
2447                 return -EINVAL;
2448
2449         if (le32_to_cpu(sb->compat_features) &&
2450             le32_to_cpu(sb->compat_features) != FEATURE_FLAG_SUPPORTS_V190) {
2451                 rs->ti->error = "Unable to assemble array: Unknown flag(s) in compatible feature flags";
2452                 return -EINVAL;
2453         }
2454
2455         if (sb->incompat_features) {
2456                 rs->ti->error = "Unable to assemble array: No incompatible feature flags supported yet";
2457                 return -EINVAL;
2458         }
2459
2460         /* Enable bitmap creation on @rs unless no metadevs or raid0 or journaled raid4/5/6 set. */
2461         mddev->bitmap_info.offset = (rt_is_raid0(rs->raid_type) || rs->journal_dev.dev) ? 0 : to_sector(4096);
2462         mddev->bitmap_info.default_offset = mddev->bitmap_info.offset;
2463
2464         if (!test_and_clear_bit(FirstUse, &rdev->flags)) {
2465                 /*
2466                  * Retrieve rdev size stored in superblock to be prepared for shrink.
2467                  * Check extended superblock members are present otherwise the size
2468                  * will not be set!
2469                  */
2470                 if (le32_to_cpu(sb->compat_features) & FEATURE_FLAG_SUPPORTS_V190)
2471                         rdev->sectors = le64_to_cpu(sb->sectors);
2472
2473                 rdev->recovery_offset = le64_to_cpu(sb->disk_recovery_offset);
2474                 if (rdev->recovery_offset == MaxSector)
2475                         set_bit(In_sync, &rdev->flags);
2476                 /*
2477                  * If no reshape in progress -> we're recovering single
2478                  * disk(s) and have to set the device(s) to out-of-sync
2479                  */
2480                 else if (!rs_is_reshaping(rs))
2481                         clear_bit(In_sync, &rdev->flags); /* Mandatory for recovery */
2482         }
2483
2484         /*
2485          * If a device comes back, set it as not In_sync and no longer faulty.
2486          */
2487         if (test_and_clear_bit(Faulty, &rdev->flags)) {
2488                 rdev->recovery_offset = 0;
2489                 clear_bit(In_sync, &rdev->flags);
2490                 rdev->saved_raid_disk = rdev->raid_disk;
2491         }
2492
2493         /* Reshape support -> restore repective data offsets */
2494         rdev->data_offset = le64_to_cpu(sb->data_offset);
2495         rdev->new_data_offset = le64_to_cpu(sb->new_data_offset);
2496
2497         return 0;
2498 }
2499
2500 /*
2501  * Analyse superblocks and select the freshest.
2502  */
2503 static int analyse_superblocks(struct dm_target *ti, struct raid_set *rs)
2504 {
2505         int r;
2506         struct md_rdev *rdev, *freshest;
2507         struct mddev *mddev = &rs->md;
2508
2509         freshest = NULL;
2510         rdev_for_each(rdev, mddev) {
2511                 if (test_bit(Journal, &rdev->flags))
2512                         continue;
2513
2514                 if (!rdev->meta_bdev)
2515                         continue;
2516
2517                 /* Set superblock offset/size for metadata device. */
2518                 rdev->sb_start = 0;
2519                 rdev->sb_size = bdev_logical_block_size(rdev->meta_bdev);
2520                 if (rdev->sb_size < sizeof(struct dm_raid_superblock) || rdev->sb_size > PAGE_SIZE) {
2521                         DMERR("superblock size of a logical block is no longer valid");
2522                         return -EINVAL;
2523                 }
2524
2525                 /*
2526                  * Skipping super_load due to CTR_FLAG_SYNC will cause
2527                  * the array to undergo initialization again as
2528                  * though it were new.  This is the intended effect
2529                  * of the "sync" directive.
2530                  *
2531                  * With reshaping capability added, we must ensure that
2532                  * the "sync" directive is disallowed during the reshape.
2533                  */
2534                 if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags))
2535                         continue;
2536
2537                 r = super_load(rdev, freshest);
2538
2539                 switch (r) {
2540                 case 1:
2541                         freshest = rdev;
2542                         break;
2543                 case 0:
2544                         break;
2545                 default:
2546                         /* This is a failure to read the superblock from the metadata device. */
2547                         /*
2548                          * We have to keep any raid0 data/metadata device pairs or
2549                          * the MD raid0 personality will fail to start the array.
2550                          */
2551                         if (rs_is_raid0(rs))
2552                                 continue;
2553
2554                         /*
2555                          * We keep the dm_devs to be able to emit the device tuple
2556                          * properly on the table line in raid_status() (rather than
2557                          * mistakenly acting as if '- -' got passed into the constructor).
2558                          *
2559                          * The rdev has to stay on the same_set list to allow for
2560                          * the attempt to restore faulty devices on second resume.
2561                          */
2562                         rdev->raid_disk = rdev->saved_raid_disk = -1;
2563                         break;
2564                 }
2565         }
2566
2567         if (!freshest)
2568                 return 0;
2569
2570         /*
2571          * Validation of the freshest device provides the source of
2572          * validation for the remaining devices.
2573          */
2574         rs->ti->error = "Unable to assemble array: Invalid superblocks";
2575         if (super_validate(rs, freshest))
2576                 return -EINVAL;
2577
2578         if (validate_raid_redundancy(rs)) {
2579                 rs->ti->error = "Insufficient redundancy to activate array";
2580                 return -EINVAL;
2581         }
2582
2583         rdev_for_each(rdev, mddev)
2584                 if (!test_bit(Journal, &rdev->flags) &&
2585                     rdev != freshest &&
2586                     super_validate(rs, rdev))
2587                         return -EINVAL;
2588         return 0;
2589 }
2590
2591 /*
2592  * Adjust data_offset and new_data_offset on all disk members of @rs
2593  * for out of place reshaping if requested by constructor
2594  *
2595  * We need free space at the beginning of each raid disk for forward
2596  * and at the end for backward reshapes which userspace has to provide
2597  * via remapping/reordering of space.
2598  */
2599 static int rs_adjust_data_offsets(struct raid_set *rs)
2600 {
2601         sector_t data_offset = 0, new_data_offset = 0;
2602         struct md_rdev *rdev;
2603
2604         /* Constructor did not request data offset change */
2605         if (!test_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags)) {
2606                 if (!rs_is_reshapable(rs))
2607                         goto out;
2608
2609                 return 0;
2610         }
2611
2612         /* HM FIXME: get In_Sync raid_dev? */
2613         rdev = &rs->dev[0].rdev;
2614
2615         if (rs->delta_disks < 0) {
2616                 /*
2617                  * Removing disks (reshaping backwards):
2618                  *
2619                  * - before reshape: data is at offset 0 and free space
2620                  *                   is at end of each component LV
2621                  *
2622                  * - after reshape: data is at offset rs->data_offset != 0 on each component LV
2623                  */
2624                 data_offset = 0;
2625                 new_data_offset = rs->data_offset;
2626
2627         } else if (rs->delta_disks > 0) {
2628                 /*
2629                  * Adding disks (reshaping forwards):
2630                  *
2631                  * - before reshape: data is at offset rs->data_offset != 0 and
2632                  *                   free space is at begin of each component LV
2633                  *
2634                  * - after reshape: data is at offset 0 on each component LV
2635                  */
2636                 data_offset = rs->data_offset;
2637                 new_data_offset = 0;
2638
2639         } else {
2640                 /*
2641                  * User space passes in 0 for data offset after having removed reshape space
2642                  *
2643                  * - or - (data offset != 0)
2644                  *
2645                  * Changing RAID layout or chunk size -> toggle offsets
2646                  *
2647                  * - before reshape: data is at offset rs->data_offset 0 and
2648                  *                   free space is at end of each component LV
2649                  *                   -or-
2650                  *                   data is at offset rs->data_offset != 0 and
2651                  *                   free space is at begin of each component LV
2652                  *
2653                  * - after reshape: data is at offset 0 if it was at offset != 0
2654                  *                  or at offset != 0 if it was at offset 0
2655                  *                  on each component LV
2656                  *
2657                  */
2658                 data_offset = rs->data_offset ? rdev->data_offset : 0;
2659                 new_data_offset = data_offset ? 0 : rs->data_offset;
2660                 set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
2661         }
2662
2663         /*
2664          * Make sure we got a minimum amount of free sectors per device
2665          */
2666         if (rs->data_offset &&
2667             bdev_nr_sectors(rdev->bdev) - rs->md.dev_sectors < MIN_FREE_RESHAPE_SPACE) {
2668                 rs->ti->error = data_offset ? "No space for forward reshape" :
2669                                               "No space for backward reshape";
2670                 return -ENOSPC;
2671         }
2672 out:
2673         /*
2674          * Raise recovery_cp in case data_offset != 0 to
2675          * avoid false recovery positives in the constructor.
2676          */
2677         if (rs->md.recovery_cp < rs->md.dev_sectors)
2678                 rs->md.recovery_cp += rs->dev[0].rdev.data_offset;
2679
2680         /* Adjust data offsets on all rdevs but on any raid4/5/6 journal device */
2681         rdev_for_each(rdev, &rs->md) {
2682                 if (!test_bit(Journal, &rdev->flags)) {
2683                         rdev->data_offset = data_offset;
2684                         rdev->new_data_offset = new_data_offset;
2685                 }
2686         }
2687
2688         return 0;
2689 }
2690
2691 /* Userpace reordered disks -> adjust raid_disk indexes in @rs */
2692 static void __reorder_raid_disk_indexes(struct raid_set *rs)
2693 {
2694         int i = 0;
2695         struct md_rdev *rdev;
2696
2697         rdev_for_each(rdev, &rs->md) {
2698                 if (!test_bit(Journal, &rdev->flags)) {
2699                         rdev->raid_disk = i++;
2700                         rdev->saved_raid_disk = rdev->new_raid_disk = -1;
2701                 }
2702         }
2703 }
2704
2705 /*
2706  * Setup @rs for takeover by a different raid level
2707  */
2708 static int rs_setup_takeover(struct raid_set *rs)
2709 {
2710         struct mddev *mddev = &rs->md;
2711         struct md_rdev *rdev;
2712         unsigned int d = mddev->raid_disks = rs->raid_disks;
2713         sector_t new_data_offset = rs->dev[0].rdev.data_offset ? 0 : rs->data_offset;
2714
2715         if (rt_is_raid10(rs->raid_type)) {
2716                 if (rs_is_raid0(rs)) {
2717                         /* Userpace reordered disks -> adjust raid_disk indexes */
2718                         __reorder_raid_disk_indexes(rs);
2719
2720                         /* raid0 -> raid10_far layout */
2721                         mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_FAR,
2722                                                                    rs->raid10_copies);
2723                 } else if (rs_is_raid1(rs))
2724                         /* raid1 -> raid10_near layout */
2725                         mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_NEAR,
2726                                                                    rs->raid_disks);
2727                 else
2728                         return -EINVAL;
2729
2730         }
2731
2732         clear_bit(MD_ARRAY_FIRST_USE, &mddev->flags);
2733         mddev->recovery_cp = MaxSector;
2734
2735         while (d--) {
2736                 rdev = &rs->dev[d].rdev;
2737
2738                 if (test_bit(d, (void *) rs->rebuild_disks)) {
2739                         clear_bit(In_sync, &rdev->flags);
2740                         clear_bit(Faulty, &rdev->flags);
2741                         mddev->recovery_cp = rdev->recovery_offset = 0;
2742                         /* Bitmap has to be created when we do an "up" takeover */
2743                         set_bit(MD_ARRAY_FIRST_USE, &mddev->flags);
2744                 }
2745
2746                 rdev->new_data_offset = new_data_offset;
2747         }
2748
2749         return 0;
2750 }
2751
2752 /* Prepare @rs for reshape */
2753 static int rs_prepare_reshape(struct raid_set *rs)
2754 {
2755         bool reshape;
2756         struct mddev *mddev = &rs->md;
2757
2758         if (rs_is_raid10(rs)) {
2759                 if (rs->raid_disks != mddev->raid_disks &&
2760                     __is_raid10_near(mddev->layout) &&
2761                     rs->raid10_copies &&
2762                     rs->raid10_copies != __raid10_near_copies(mddev->layout)) {
2763                         /*
2764                          * raid disk have to be multiple of data copies to allow this conversion,
2765                          *
2766                          * This is actually not a reshape it is a
2767                          * rebuild of any additional mirrors per group
2768                          */
2769                         if (rs->raid_disks % rs->raid10_copies) {
2770                                 rs->ti->error = "Can't reshape raid10 mirror groups";
2771                                 return -EINVAL;
2772                         }
2773
2774                         /* Userpace reordered disks to add/remove mirrors -> adjust raid_disk indexes */
2775                         __reorder_raid_disk_indexes(rs);
2776                         mddev->layout = raid10_format_to_md_layout(rs, ALGORITHM_RAID10_NEAR,
2777                                                                    rs->raid10_copies);
2778                         mddev->new_layout = mddev->layout;
2779                         reshape = false;
2780                 } else
2781                         reshape = true;
2782
2783         } else if (rs_is_raid456(rs))
2784                 reshape = true;
2785
2786         else if (rs_is_raid1(rs)) {
2787                 if (rs->delta_disks) {
2788                         /* Process raid1 via delta_disks */
2789                         mddev->degraded = rs->delta_disks < 0 ? -rs->delta_disks : rs->delta_disks;
2790                         reshape = true;
2791                 } else {
2792                         /* Process raid1 without delta_disks */
2793                         mddev->raid_disks = rs->raid_disks;
2794                         reshape = false;
2795                 }
2796         } else {
2797                 rs->ti->error = "Called with bogus raid type";
2798                 return -EINVAL;
2799         }
2800
2801         if (reshape) {
2802                 set_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags);
2803                 set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
2804         } else if (mddev->raid_disks < rs->raid_disks)
2805                 /* Create new superblocks and bitmaps, if any new disks */
2806                 set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
2807
2808         return 0;
2809 }
2810
2811 /* Get reshape sectors from data_offsets or raid set */
2812 static sector_t _get_reshape_sectors(struct raid_set *rs)
2813 {
2814         struct md_rdev *rdev;
2815         sector_t reshape_sectors = 0;
2816
2817         rdev_for_each(rdev, &rs->md)
2818                 if (!test_bit(Journal, &rdev->flags)) {
2819                         reshape_sectors = (rdev->data_offset > rdev->new_data_offset) ?
2820                                         rdev->data_offset - rdev->new_data_offset :
2821                                         rdev->new_data_offset - rdev->data_offset;
2822                         break;
2823                 }
2824
2825         return max(reshape_sectors, (sector_t) rs->data_offset);
2826 }
2827
2828 /*
2829  * Reshape:
2830  * - change raid layout
2831  * - change chunk size
2832  * - add disks
2833  * - remove disks
2834  */
2835 static int rs_setup_reshape(struct raid_set *rs)
2836 {
2837         int r = 0;
2838         unsigned int cur_raid_devs, d;
2839         sector_t reshape_sectors = _get_reshape_sectors(rs);
2840         struct mddev *mddev = &rs->md;
2841         struct md_rdev *rdev;
2842
2843         mddev->delta_disks = rs->delta_disks;
2844         cur_raid_devs = mddev->raid_disks;
2845
2846         /* Ignore impossible layout change whilst adding/removing disks */
2847         if (mddev->delta_disks &&
2848             mddev->layout != mddev->new_layout) {
2849                 DMINFO("Ignoring invalid layout change with delta_disks=%d", rs->delta_disks);
2850                 mddev->new_layout = mddev->layout;
2851         }
2852
2853         /*
2854          * Adjust array size:
2855          *
2856          * - in case of adding disk(s), array size has
2857          *   to grow after the disk adding reshape,
2858          *   which'll hapen in the event handler;
2859          *   reshape will happen forward, so space has to
2860          *   be available at the beginning of each disk
2861          *
2862          * - in case of removing disk(s), array size
2863          *   has to shrink before starting the reshape,
2864          *   which'll happen here;
2865          *   reshape will happen backward, so space has to
2866          *   be available at the end of each disk
2867          *
2868          * - data_offset and new_data_offset are
2869          *   adjusted for aforementioned out of place
2870          *   reshaping based on userspace passing in
2871          *   the "data_offset <sectors>" key/value
2872          *   pair via the constructor
2873          */
2874
2875         /* Add disk(s) */
2876         if (rs->delta_disks > 0) {
2877                 /* Prepare disks for check in raid4/5/6/10 {check|start}_reshape */
2878                 for (d = cur_raid_devs; d < rs->raid_disks; d++) {
2879                         rdev = &rs->dev[d].rdev;
2880                         clear_bit(In_sync, &rdev->flags);
2881
2882                         /*
2883                          * save_raid_disk needs to be -1, or recovery_offset will be set to 0
2884                          * by md, which'll store that erroneously in the superblock on reshape
2885                          */
2886                         rdev->saved_raid_disk = -1;
2887                         rdev->raid_disk = d;
2888
2889                         rdev->sectors = mddev->dev_sectors;
2890                         rdev->recovery_offset = rs_is_raid1(rs) ? 0 : MaxSector;
2891                 }
2892
2893                 mddev->reshape_backwards = 0; /* adding disk(s) -> forward reshape */
2894
2895         /* Remove disk(s) */
2896         } else if (rs->delta_disks < 0) {
2897                 r = rs_set_dev_and_array_sectors(rs, rs->ti->len, true);
2898                 mddev->reshape_backwards = 1; /* removing disk(s) -> backward reshape */
2899
2900         /* Change layout and/or chunk size */
2901         } else {
2902                 /*
2903                  * Reshape layout (e.g. raid5_ls -> raid5_n) and/or chunk size:
2904                  *
2905                  * keeping number of disks and do layout change ->
2906                  *
2907                  * toggle reshape_backward depending on data_offset:
2908                  *
2909                  * - free space upfront -> reshape forward
2910                  *
2911                  * - free space at the end -> reshape backward
2912                  *
2913                  *
2914                  * This utilizes free reshape space avoiding the need
2915                  * for userspace to move (parts of) LV segments in
2916                  * case of layout/chunksize change  (for disk
2917                  * adding/removing reshape space has to be at
2918                  * the proper address (see above with delta_disks):
2919                  *
2920                  * add disk(s)   -> begin
2921                  * remove disk(s)-> end
2922                  */
2923                 mddev->reshape_backwards = rs->dev[0].rdev.data_offset ? 0 : 1;
2924         }
2925
2926         /*
2927          * Adjust device size for forward reshape
2928          * because md_finish_reshape() reduces it.
2929          */
2930         if (!mddev->reshape_backwards)
2931                 rdev_for_each(rdev, &rs->md)
2932                         if (!test_bit(Journal, &rdev->flags))
2933                                 rdev->sectors += reshape_sectors;
2934
2935         return r;
2936 }
2937
2938 /*
2939  * If the md resync thread has updated superblock with max reshape position
2940  * at the end of a reshape but not (yet) reset the layout configuration
2941  * changes -> reset the latter.
2942  */
2943 static void rs_reset_inconclusive_reshape(struct raid_set *rs)
2944 {
2945         if (!rs_is_reshaping(rs) && rs_is_layout_change(rs, true)) {
2946                 rs_set_cur(rs);
2947                 rs->md.delta_disks = 0;
2948                 rs->md.reshape_backwards = 0;
2949         }
2950 }
2951
2952 /*
2953  * Enable/disable discard support on RAID set depending on
2954  * RAID level and discard properties of underlying RAID members.
2955  */
2956 static void configure_discard_support(struct raid_set *rs)
2957 {
2958         int i;
2959         bool raid456;
2960         struct dm_target *ti = rs->ti;
2961
2962         /*
2963          * XXX: RAID level 4,5,6 require zeroing for safety.
2964          */
2965         raid456 = rs_is_raid456(rs);
2966
2967         for (i = 0; i < rs->raid_disks; i++) {
2968                 if (!rs->dev[i].rdev.bdev ||
2969                     !bdev_max_discard_sectors(rs->dev[i].rdev.bdev))
2970                         return;
2971
2972                 if (raid456) {
2973                         if (!devices_handle_discard_safely) {
2974                                 DMERR("raid456 discard support disabled due to discard_zeroes_data uncertainty.");
2975                                 DMERR("Set dm-raid.devices_handle_discard_safely=Y to override.");
2976                                 return;
2977                         }
2978                 }
2979         }
2980
2981         ti->num_discard_bios = 1;
2982 }
2983
2984 /*
2985  * Construct a RAID0/1/10/4/5/6 mapping:
2986  * Args:
2987  *      <raid_type> <#raid_params> <raid_params>{0,}    \
2988  *      <#raid_devs> [<meta_dev1> <dev1>]{1,}
2989  *
2990  * <raid_params> varies by <raid_type>.  See 'parse_raid_params' for
2991  * details on possible <raid_params>.
2992  *
2993  * Userspace is free to initialize the metadata devices, hence the superblocks to
2994  * enforce recreation based on the passed in table parameters.
2995  *
2996  */
2997 static int raid_ctr(struct dm_target *ti, unsigned int argc, char **argv)
2998 {
2999         int r;
3000         bool resize = false;
3001         struct raid_type *rt;
3002         unsigned int num_raid_params, num_raid_devs;
3003         sector_t sb_array_sectors, rdev_sectors, reshape_sectors;
3004         struct raid_set *rs = NULL;
3005         const char *arg;
3006         struct rs_layout rs_layout;
3007         struct dm_arg_set as = { argc, argv }, as_nrd;
3008         struct dm_arg _args[] = {
3009                 { 0, as.argc, "Cannot understand number of raid parameters" },
3010                 { 1, 254, "Cannot understand number of raid devices parameters" }
3011         };
3012
3013         arg = dm_shift_arg(&as);
3014         if (!arg) {
3015                 ti->error = "No arguments";
3016                 return -EINVAL;
3017         }
3018
3019         rt = get_raid_type(arg);
3020         if (!rt) {
3021                 ti->error = "Unrecognised raid_type";
3022                 return -EINVAL;
3023         }
3024
3025         /* Must have <#raid_params> */
3026         if (dm_read_arg_group(_args, &as, &num_raid_params, &ti->error))
3027                 return -EINVAL;
3028
3029         /* number of raid device tupples <meta_dev data_dev> */
3030         as_nrd = as;
3031         dm_consume_args(&as_nrd, num_raid_params);
3032         _args[1].max = (as_nrd.argc - 1) / 2;
3033         if (dm_read_arg(_args + 1, &as_nrd, &num_raid_devs, &ti->error))
3034                 return -EINVAL;
3035
3036         if (!__within_range(num_raid_devs, 1, MAX_RAID_DEVICES)) {
3037                 ti->error = "Invalid number of supplied raid devices";
3038                 return -EINVAL;
3039         }
3040
3041         rs = raid_set_alloc(ti, rt, num_raid_devs);
3042         if (IS_ERR(rs))
3043                 return PTR_ERR(rs);
3044
3045         r = parse_raid_params(rs, &as, num_raid_params);
3046         if (r)
3047                 goto bad;
3048
3049         r = parse_dev_params(rs, &as);
3050         if (r)
3051                 goto bad;
3052
3053         rs->md.sync_super = super_sync;
3054
3055         /*
3056          * Calculate ctr requested array and device sizes to allow
3057          * for superblock analysis needing device sizes defined.
3058          *
3059          * Any existing superblock will overwrite the array and device sizes
3060          */
3061         r = rs_set_dev_and_array_sectors(rs, rs->ti->len, false);
3062         if (r)
3063                 goto bad;
3064
3065         /* Memorize just calculated, potentially larger sizes to grow the raid set in preresume */
3066         rs->array_sectors = rs->md.array_sectors;
3067         rs->dev_sectors = rs->md.dev_sectors;
3068
3069         /*
3070          * Backup any new raid set level, layout, ...
3071          * requested to be able to compare to superblock
3072          * members for conversion decisions.
3073          */
3074         rs_config_backup(rs, &rs_layout);
3075
3076         r = analyse_superblocks(ti, rs);
3077         if (r)
3078                 goto bad;
3079
3080         /* All in-core metadata now as of current superblocks after calling analyse_superblocks() */
3081         sb_array_sectors = rs->md.array_sectors;
3082         rdev_sectors = __rdev_sectors(rs);
3083         if (!rdev_sectors) {
3084                 ti->error = "Invalid rdev size";
3085                 r = -EINVAL;
3086                 goto bad;
3087         }
3088
3089
3090         reshape_sectors = _get_reshape_sectors(rs);
3091         if (rs->dev_sectors != rdev_sectors) {
3092                 resize = (rs->dev_sectors != rdev_sectors - reshape_sectors);
3093                 if (rs->dev_sectors > rdev_sectors - reshape_sectors)
3094                         set_bit(RT_FLAG_RS_GROW, &rs->runtime_flags);
3095         }
3096
3097         INIT_WORK(&rs->md.event_work, do_table_event);
3098         ti->private = rs;
3099         ti->num_flush_bios = 1;
3100         ti->needs_bio_set_dev = true;
3101
3102         /* Restore any requested new layout for conversion decision */
3103         rs_config_restore(rs, &rs_layout);
3104
3105         /*
3106          * Now that we have any superblock metadata available,
3107          * check for new, recovering, reshaping, to be taken over,
3108          * to be reshaped or an existing, unchanged raid set to
3109          * run in sequence.
3110          */
3111         if (test_bit(MD_ARRAY_FIRST_USE, &rs->md.flags)) {
3112                 /* A new raid6 set has to be recovered to ensure proper parity and Q-Syndrome */
3113                 if (rs_is_raid6(rs) &&
3114                     test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags)) {
3115                         ti->error = "'nosync' not allowed for new raid6 set";
3116                         r = -EINVAL;
3117                         goto bad;
3118                 }
3119                 rs_setup_recovery(rs, 0);
3120                 set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
3121                 rs_set_new(rs);
3122         } else if (rs_is_recovering(rs)) {
3123                 /* A recovering raid set may be resized */
3124                 goto size_check;
3125         } else if (rs_is_reshaping(rs)) {
3126                 /* Have to reject size change request during reshape */
3127                 if (resize) {
3128                         ti->error = "Can't resize a reshaping raid set";
3129                         r = -EPERM;
3130                         goto bad;
3131                 }
3132                 /* skip setup rs */
3133         } else if (rs_takeover_requested(rs)) {
3134                 if (rs_is_reshaping(rs)) {
3135                         ti->error = "Can't takeover a reshaping raid set";
3136                         r = -EPERM;
3137                         goto bad;
3138                 }
3139
3140                 /* We can't takeover a journaled raid4/5/6 */
3141                 if (test_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags)) {
3142                         ti->error = "Can't takeover a journaled raid4/5/6 set";
3143                         r = -EPERM;
3144                         goto bad;
3145                 }
3146
3147                 /*
3148                  * If a takeover is needed, userspace sets any additional
3149                  * devices to rebuild and we can check for a valid request here.
3150                  *
3151                  * If acceptible, set the level to the new requested
3152                  * one, prohibit requesting recovery, allow the raid
3153                  * set to run and store superblocks during resume.
3154                  */
3155                 r = rs_check_takeover(rs);
3156                 if (r)
3157                         goto bad;
3158
3159                 r = rs_setup_takeover(rs);
3160                 if (r)
3161                         goto bad;
3162
3163                 set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
3164                 /* Takeover ain't recovery, so disable recovery */
3165                 rs_setup_recovery(rs, MaxSector);
3166                 rs_set_new(rs);
3167         } else if (rs_reshape_requested(rs)) {
3168                 /* Only request grow on raid set size extensions, not on reshapes. */
3169                 clear_bit(RT_FLAG_RS_GROW, &rs->runtime_flags);
3170
3171                 /*
3172                  * No need to check for 'ongoing' takeover here, because takeover
3173                  * is an instant operation as oposed to an ongoing reshape.
3174                  */
3175
3176                 /* We can't reshape a journaled raid4/5/6 */
3177                 if (test_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags)) {
3178                         ti->error = "Can't reshape a journaled raid4/5/6 set";
3179                         r = -EPERM;
3180                         goto bad;
3181                 }
3182
3183                 /* Out-of-place space has to be available to allow for a reshape unless raid1! */
3184                 if (reshape_sectors || rs_is_raid1(rs)) {
3185                         /*
3186                           * We can only prepare for a reshape here, because the
3187                           * raid set needs to run to provide the repective reshape
3188                           * check functions via its MD personality instance.
3189                           *
3190                           * So do the reshape check after md_run() succeeded.
3191                           */
3192                         r = rs_prepare_reshape(rs);
3193                         if (r)
3194                                 goto bad;
3195
3196                         /* Reshaping ain't recovery, so disable recovery */
3197                         rs_setup_recovery(rs, MaxSector);
3198                 }
3199                 rs_set_cur(rs);
3200         } else {
3201 size_check:
3202                 /* May not set recovery when a device rebuild is requested */
3203                 if (test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags)) {
3204                         clear_bit(RT_FLAG_RS_GROW, &rs->runtime_flags);
3205                         set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
3206                         rs_setup_recovery(rs, MaxSector);
3207                 } else if (test_bit(RT_FLAG_RS_GROW, &rs->runtime_flags)) {
3208                         /*
3209                          * Set raid set to current size, i.e. size as of
3210                          * superblocks to grow to larger size in preresume.
3211                          */
3212                         r = rs_set_dev_and_array_sectors(rs, sb_array_sectors, false);
3213                         if (r)
3214                                 goto bad;
3215
3216                         rs_setup_recovery(rs, rs->md.recovery_cp < rs->md.dev_sectors ? rs->md.recovery_cp : rs->md.dev_sectors);
3217                 } else {
3218                         /* This is no size change or it is shrinking, update size and record in superblocks */
3219                         r = rs_set_dev_and_array_sectors(rs, rs->ti->len, false);
3220                         if (r)
3221                                 goto bad;
3222
3223                         if (sb_array_sectors > rs->array_sectors)
3224                                 set_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags);
3225                 }
3226                 rs_set_cur(rs);
3227         }
3228
3229         /* If constructor requested it, change data and new_data offsets */
3230         r = rs_adjust_data_offsets(rs);
3231         if (r)
3232                 goto bad;
3233
3234         /* Catch any inconclusive reshape superblock content. */
3235         rs_reset_inconclusive_reshape(rs);
3236
3237         /* Start raid set read-only and assumed clean to change in raid_resume() */
3238         rs->md.ro = 1;
3239         rs->md.in_sync = 1;
3240
3241         /* Keep array frozen until resume. */
3242         set_bit(MD_RECOVERY_FROZEN, &rs->md.recovery);
3243
3244         /* Has to be held on running the array */
3245         mddev_lock_nointr(&rs->md);
3246         r = md_run(&rs->md);
3247         rs->md.in_sync = 0; /* Assume already marked dirty */
3248         if (r) {
3249                 ti->error = "Failed to run raid array";
3250                 mddev_unlock(&rs->md);
3251                 goto bad;
3252         }
3253
3254         r = md_start(&rs->md);
3255         if (r) {
3256                 ti->error = "Failed to start raid array";
3257                 mddev_unlock(&rs->md);
3258                 goto bad_md_start;
3259         }
3260
3261         /* If raid4/5/6 journal mode explicitly requested (only possible with journal dev) -> set it */
3262         if (test_bit(__CTR_FLAG_JOURNAL_MODE, &rs->ctr_flags)) {
3263                 r = r5c_journal_mode_set(&rs->md, rs->journal_dev.mode);
3264                 if (r) {
3265                         ti->error = "Failed to set raid4/5/6 journal mode";
3266                         mddev_unlock(&rs->md);
3267                         goto bad_journal_mode_set;
3268                 }
3269         }
3270
3271         mddev_suspend(&rs->md);
3272         set_bit(RT_FLAG_RS_SUSPENDED, &rs->runtime_flags);
3273
3274         /* Try to adjust the raid4/5/6 stripe cache size to the stripe size */
3275         if (rs_is_raid456(rs)) {
3276                 r = rs_set_raid456_stripe_cache(rs);
3277                 if (r)
3278                         goto bad_stripe_cache;
3279         }
3280
3281         /* Now do an early reshape check */
3282         if (test_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags)) {
3283                 r = rs_check_reshape(rs);
3284                 if (r)
3285                         goto bad_check_reshape;
3286
3287                 /* Restore new, ctr requested layout to perform check */
3288                 rs_config_restore(rs, &rs_layout);
3289
3290                 if (rs->md.pers->start_reshape) {
3291                         r = rs->md.pers->check_reshape(&rs->md);
3292                         if (r) {
3293                                 ti->error = "Reshape check failed";
3294                                 goto bad_check_reshape;
3295                         }
3296                 }
3297         }
3298
3299         /* Disable/enable discard support on raid set. */
3300         configure_discard_support(rs);
3301
3302         mddev_unlock(&rs->md);
3303         return 0;
3304
3305 bad_md_start:
3306 bad_journal_mode_set:
3307 bad_stripe_cache:
3308 bad_check_reshape:
3309         md_stop(&rs->md);
3310 bad:
3311         raid_set_free(rs);
3312
3313         return r;
3314 }
3315
3316 static void raid_dtr(struct dm_target *ti)
3317 {
3318         struct raid_set *rs = ti->private;
3319
3320         md_stop(&rs->md);
3321         raid_set_free(rs);
3322 }
3323
3324 static int raid_map(struct dm_target *ti, struct bio *bio)
3325 {
3326         struct raid_set *rs = ti->private;
3327         struct mddev *mddev = &rs->md;
3328
3329         /*
3330          * If we're reshaping to add disk(s)), ti->len and
3331          * mddev->array_sectors will differ during the process
3332          * (ti->len > mddev->array_sectors), so we have to requeue
3333          * bios with addresses > mddev->array_sectors here or
3334          * there will occur accesses past EOD of the component
3335          * data images thus erroring the raid set.
3336          */
3337         if (unlikely(bio_end_sector(bio) > mddev->array_sectors))
3338                 return DM_MAPIO_REQUEUE;
3339
3340         md_handle_request(mddev, bio);
3341
3342         return DM_MAPIO_SUBMITTED;
3343 }
3344
3345 /* Return sync state string for @state */
3346 enum sync_state { st_frozen, st_reshape, st_resync, st_check, st_repair, st_recover, st_idle };
3347 static const char *sync_str(enum sync_state state)
3348 {
3349         /* Has to be in above sync_state order! */
3350         static const char *sync_strs[] = {
3351                 "frozen",
3352                 "reshape",
3353                 "resync",
3354                 "check",
3355                 "repair",
3356                 "recover",
3357                 "idle"
3358         };
3359
3360         return __within_range(state, 0, ARRAY_SIZE(sync_strs) - 1) ? sync_strs[state] : "undef";
3361 };
3362
3363 /* Return enum sync_state for @mddev derived from @recovery flags */
3364 static enum sync_state decipher_sync_action(struct mddev *mddev, unsigned long recovery)
3365 {
3366         if (test_bit(MD_RECOVERY_FROZEN, &recovery))
3367                 return st_frozen;
3368
3369         /* The MD sync thread can be done with io or be interrupted but still be running */
3370         if (!test_bit(MD_RECOVERY_DONE, &recovery) &&
3371             (test_bit(MD_RECOVERY_RUNNING, &recovery) ||
3372              (!mddev->ro && test_bit(MD_RECOVERY_NEEDED, &recovery)))) {
3373                 if (test_bit(MD_RECOVERY_RESHAPE, &recovery))
3374                         return st_reshape;
3375
3376                 if (test_bit(MD_RECOVERY_SYNC, &recovery)) {
3377                         if (!test_bit(MD_RECOVERY_REQUESTED, &recovery))
3378                                 return st_resync;
3379                         if (test_bit(MD_RECOVERY_CHECK, &recovery))
3380                                 return st_check;
3381                         return st_repair;
3382                 }
3383
3384                 if (test_bit(MD_RECOVERY_RECOVER, &recovery))
3385                         return st_recover;
3386
3387                 if (mddev->reshape_position != MaxSector)
3388                         return st_reshape;
3389         }
3390
3391         return st_idle;
3392 }
3393
3394 /*
3395  * Return status string for @rdev
3396  *
3397  * Status characters:
3398  *
3399  *  'D' = Dead/Failed raid set component or raid4/5/6 journal device
3400  *  'a' = Alive but not in-sync raid set component _or_ alive raid4/5/6 'write_back' journal device
3401  *  'A' = Alive and in-sync raid set component _or_ alive raid4/5/6 'write_through' journal device
3402  *  '-' = Non-existing device (i.e. uspace passed '- -' into the ctr)
3403  */
3404 static const char *__raid_dev_status(struct raid_set *rs, struct md_rdev *rdev)
3405 {
3406         if (!rdev->bdev)
3407                 return "-";
3408         else if (test_bit(Faulty, &rdev->flags))
3409                 return "D";
3410         else if (test_bit(Journal, &rdev->flags))
3411                 return (rs->journal_dev.mode == R5C_JOURNAL_MODE_WRITE_THROUGH) ? "A" : "a";
3412         else if (test_bit(RT_FLAG_RS_RESYNCING, &rs->runtime_flags) ||
3413                  (!test_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags) &&
3414                   !test_bit(In_sync, &rdev->flags)))
3415                 return "a";
3416         else
3417                 return "A";
3418 }
3419
3420 /* Helper to return resync/reshape progress for @rs and runtime flags for raid set in sync / resynching */
3421 static sector_t rs_get_progress(struct raid_set *rs, unsigned long recovery,
3422                                 enum sync_state state, sector_t resync_max_sectors)
3423 {
3424         sector_t r;
3425         struct mddev *mddev = &rs->md;
3426
3427         clear_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags);
3428         clear_bit(RT_FLAG_RS_RESYNCING, &rs->runtime_flags);
3429
3430         if (rs_is_raid0(rs)) {
3431                 r = resync_max_sectors;
3432                 set_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags);
3433
3434         } else {
3435                 if (state == st_idle && !test_bit(MD_RECOVERY_INTR, &recovery))
3436                         r = mddev->recovery_cp;
3437                 else
3438                         r = mddev->curr_resync_completed;
3439
3440                 if (state == st_idle && r >= resync_max_sectors) {
3441                         /*
3442                          * Sync complete.
3443                          */
3444                         /* In case we have finished recovering, the array is in sync. */
3445                         if (test_bit(MD_RECOVERY_RECOVER, &recovery))
3446                                 set_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags);
3447
3448                 } else if (state == st_recover)
3449                         /*
3450                          * In case we are recovering, the array is not in sync
3451                          * and health chars should show the recovering legs.
3452                          *
3453                          * Already retrieved recovery offset from curr_resync_completed above.
3454                          */
3455                         ;
3456
3457                 else if (state == st_resync || state == st_reshape)
3458                         /*
3459                          * If "resync/reshape" is occurring, the raid set
3460                          * is or may be out of sync hence the health
3461                          * characters shall be 'a'.
3462                          */
3463                         set_bit(RT_FLAG_RS_RESYNCING, &rs->runtime_flags);
3464
3465                 else if (state == st_check || state == st_repair)
3466                         /*
3467                          * If "check" or "repair" is occurring, the raid set has
3468                          * undergone an initial sync and the health characters
3469                          * should not be 'a' anymore.
3470                          */
3471                         set_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags);
3472
3473                 else if (test_bit(MD_RECOVERY_NEEDED, &recovery))
3474                         /*
3475                          * We are idle and recovery is needed, prevent 'A' chars race
3476                          * caused by components still set to in-sync by constructor.
3477                          */
3478                         set_bit(RT_FLAG_RS_RESYNCING, &rs->runtime_flags);
3479
3480                 else {
3481                         /*
3482                          * We are idle and the raid set may be doing an initial
3483                          * sync, or it may be rebuilding individual components.
3484                          * If all the devices are In_sync, then it is the raid set
3485                          * that is being initialized.
3486                          */
3487                         struct md_rdev *rdev;
3488
3489                         set_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags);
3490                         rdev_for_each(rdev, mddev)
3491                                 if (!test_bit(Journal, &rdev->flags) &&
3492                                     !test_bit(In_sync, &rdev->flags)) {
3493                                         clear_bit(RT_FLAG_RS_IN_SYNC, &rs->runtime_flags);
3494                                         break;
3495                                 }
3496                 }
3497         }
3498
3499         return min(r, resync_max_sectors);
3500 }
3501
3502 /* Helper to return @dev name or "-" if !@dev */
3503 static const char *__get_dev_name(struct dm_dev *dev)
3504 {
3505         return dev ? dev->name : "-";
3506 }
3507
3508 static void raid_status(struct dm_target *ti, status_type_t type,
3509                         unsigned int status_flags, char *result, unsigned int maxlen)
3510 {
3511         struct raid_set *rs = ti->private;
3512         struct mddev *mddev = &rs->md;
3513         struct r5conf *conf = rs_is_raid456(rs) ? mddev->private : NULL;
3514         int i, max_nr_stripes = conf ? conf->max_nr_stripes : 0;
3515         unsigned long recovery;
3516         unsigned int raid_param_cnt = 1; /* at least 1 for chunksize */
3517         unsigned int sz = 0;
3518         unsigned int rebuild_writemostly_count = 0;
3519         sector_t progress, resync_max_sectors, resync_mismatches;
3520         enum sync_state state;
3521         struct raid_type *rt;
3522
3523         switch (type) {
3524         case STATUSTYPE_INFO:
3525                 /* *Should* always succeed */
3526                 rt = get_raid_type_by_ll(mddev->new_level, mddev->new_layout);
3527                 if (!rt)
3528                         return;
3529
3530                 DMEMIT("%s %d ", rt->name, mddev->raid_disks);
3531
3532                 /* Access most recent mddev properties for status output */
3533                 smp_rmb();
3534                 /* Get sensible max sectors even if raid set not yet started */
3535                 resync_max_sectors = test_bit(RT_FLAG_RS_PRERESUMED, &rs->runtime_flags) ?
3536                                       mddev->resync_max_sectors : mddev->dev_sectors;
3537                 recovery = rs->md.recovery;
3538                 state = decipher_sync_action(mddev, recovery);
3539                 progress = rs_get_progress(rs, recovery, state, resync_max_sectors);
3540                 resync_mismatches = (mddev->last_sync_action && !strcasecmp(mddev->last_sync_action, "check")) ?
3541                                     atomic64_read(&mddev->resync_mismatches) : 0;
3542
3543                 /* HM FIXME: do we want another state char for raid0? It shows 'D'/'A'/'-' now */
3544                 for (i = 0; i < rs->raid_disks; i++)
3545                         DMEMIT(__raid_dev_status(rs, &rs->dev[i].rdev));
3546
3547                 /*
3548                  * In-sync/Reshape ratio:
3549                  *  The in-sync ratio shows the progress of:
3550                  *   - Initializing the raid set
3551                  *   - Rebuilding a subset of devices of the raid set
3552                  *  The user can distinguish between the two by referring
3553                  *  to the status characters.
3554                  *
3555                  *  The reshape ratio shows the progress of
3556                  *  changing the raid layout or the number of
3557                  *  disks of a raid set
3558                  */
3559                 DMEMIT(" %llu/%llu", (unsigned long long) progress,
3560                                      (unsigned long long) resync_max_sectors);
3561
3562                 /*
3563                  * v1.5.0+:
3564                  *
3565                  * Sync action:
3566                  *   See Documentation/admin-guide/device-mapper/dm-raid.rst for
3567                  *   information on each of these states.
3568                  */
3569                 DMEMIT(" %s", sync_str(state));
3570
3571                 /*
3572                  * v1.5.0+:
3573                  *
3574                  * resync_mismatches/mismatch_cnt
3575                  *   This field shows the number of discrepancies found when
3576                  *   performing a "check" of the raid set.
3577                  */
3578                 DMEMIT(" %llu", (unsigned long long) resync_mismatches);
3579
3580                 /*
3581                  * v1.9.0+:
3582                  *
3583                  * data_offset (needed for out of space reshaping)
3584                  *   This field shows the data offset into the data
3585                  *   image LV where the first stripes data starts.
3586                  *
3587                  * We keep data_offset equal on all raid disks of the set,
3588                  * so retrieving it from the first raid disk is sufficient.
3589                  */
3590                 DMEMIT(" %llu", (unsigned long long) rs->dev[0].rdev.data_offset);
3591
3592                 /*
3593                  * v1.10.0+:
3594                  */
3595                 DMEMIT(" %s", test_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags) ?
3596                               __raid_dev_status(rs, &rs->journal_dev.rdev) : "-");
3597                 break;
3598
3599         case STATUSTYPE_TABLE:
3600                 /* Report the table line string you would use to construct this raid set */
3601
3602                 /*
3603                  * Count any rebuild or writemostly argument pairs and subtract the
3604                  * hweight count being added below of any rebuild and writemostly ctr flags.
3605                  */
3606                 for (i = 0; i < rs->raid_disks; i++) {
3607                         rebuild_writemostly_count += (test_bit(i, (void *) rs->rebuild_disks) ? 2 : 0) +
3608                                                      (test_bit(WriteMostly, &rs->dev[i].rdev.flags) ? 2 : 0);
3609                 }
3610                 rebuild_writemostly_count -= (test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags) ? 2 : 0) +
3611                                              (test_bit(__CTR_FLAG_WRITE_MOSTLY, &rs->ctr_flags) ? 2 : 0);
3612                 /* Calculate raid parameter count based on ^ rebuild/writemostly argument counts and ctr flags set. */
3613                 raid_param_cnt += rebuild_writemostly_count +
3614                                   hweight32(rs->ctr_flags & CTR_FLAG_OPTIONS_NO_ARGS) +
3615                                   hweight32(rs->ctr_flags & CTR_FLAG_OPTIONS_ONE_ARG) * 2;
3616                 /* Emit table line */
3617                 /* This has to be in the documented order for userspace! */
3618                 DMEMIT("%s %u %u", rs->raid_type->name, raid_param_cnt, mddev->new_chunk_sectors);
3619                 if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags))
3620                         DMEMIT(" %s", dm_raid_arg_name_by_flag(CTR_FLAG_SYNC));
3621                 if (test_bit(__CTR_FLAG_NOSYNC, &rs->ctr_flags))
3622                         DMEMIT(" %s", dm_raid_arg_name_by_flag(CTR_FLAG_NOSYNC));
3623                 if (test_bit(__CTR_FLAG_REBUILD, &rs->ctr_flags))
3624                         for (i = 0; i < rs->raid_disks; i++)
3625                                 if (test_bit(i, (void *) rs->rebuild_disks))
3626                                         DMEMIT(" %s %u", dm_raid_arg_name_by_flag(CTR_FLAG_REBUILD), i);
3627                 if (test_bit(__CTR_FLAG_DAEMON_SLEEP, &rs->ctr_flags))
3628                         DMEMIT(" %s %lu", dm_raid_arg_name_by_flag(CTR_FLAG_DAEMON_SLEEP),
3629                                           mddev->bitmap_info.daemon_sleep);
3630                 if (test_bit(__CTR_FLAG_MIN_RECOVERY_RATE, &rs->ctr_flags))
3631                         DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_MIN_RECOVERY_RATE),
3632                                          mddev->sync_speed_min);
3633                 if (test_bit(__CTR_FLAG_MAX_RECOVERY_RATE, &rs->ctr_flags))
3634                         DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_MAX_RECOVERY_RATE),
3635                                          mddev->sync_speed_max);
3636                 if (test_bit(__CTR_FLAG_WRITE_MOSTLY, &rs->ctr_flags))
3637                         for (i = 0; i < rs->raid_disks; i++)
3638                                 if (test_bit(WriteMostly, &rs->dev[i].rdev.flags))
3639                                         DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_WRITE_MOSTLY),
3640                                                rs->dev[i].rdev.raid_disk);
3641                 if (test_bit(__CTR_FLAG_MAX_WRITE_BEHIND, &rs->ctr_flags))
3642                         DMEMIT(" %s %lu", dm_raid_arg_name_by_flag(CTR_FLAG_MAX_WRITE_BEHIND),
3643                                           mddev->bitmap_info.max_write_behind);
3644                 if (test_bit(__CTR_FLAG_STRIPE_CACHE, &rs->ctr_flags))
3645                         DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_STRIPE_CACHE),
3646                                          max_nr_stripes);
3647                 if (test_bit(__CTR_FLAG_REGION_SIZE, &rs->ctr_flags))
3648                         DMEMIT(" %s %llu", dm_raid_arg_name_by_flag(CTR_FLAG_REGION_SIZE),
3649                                            (unsigned long long) to_sector(mddev->bitmap_info.chunksize));
3650                 if (test_bit(__CTR_FLAG_RAID10_COPIES, &rs->ctr_flags))
3651                         DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_COPIES),
3652                                          raid10_md_layout_to_copies(mddev->layout));
3653                 if (test_bit(__CTR_FLAG_RAID10_FORMAT, &rs->ctr_flags))
3654                         DMEMIT(" %s %s", dm_raid_arg_name_by_flag(CTR_FLAG_RAID10_FORMAT),
3655                                          raid10_md_layout_to_format(mddev->layout));
3656                 if (test_bit(__CTR_FLAG_DELTA_DISKS, &rs->ctr_flags))
3657                         DMEMIT(" %s %d", dm_raid_arg_name_by_flag(CTR_FLAG_DELTA_DISKS),
3658                                          max(rs->delta_disks, mddev->delta_disks));
3659                 if (test_bit(__CTR_FLAG_DATA_OFFSET, &rs->ctr_flags))
3660                         DMEMIT(" %s %llu", dm_raid_arg_name_by_flag(CTR_FLAG_DATA_OFFSET),
3661                                            (unsigned long long) rs->data_offset);
3662                 if (test_bit(__CTR_FLAG_JOURNAL_DEV, &rs->ctr_flags))
3663                         DMEMIT(" %s %s", dm_raid_arg_name_by_flag(CTR_FLAG_JOURNAL_DEV),
3664                                         __get_dev_name(rs->journal_dev.dev));
3665                 if (test_bit(__CTR_FLAG_JOURNAL_MODE, &rs->ctr_flags))
3666                         DMEMIT(" %s %s", dm_raid_arg_name_by_flag(CTR_FLAG_JOURNAL_MODE),
3667                                          md_journal_mode_to_dm_raid(rs->journal_dev.mode));
3668                 DMEMIT(" %d", rs->raid_disks);
3669                 for (i = 0; i < rs->raid_disks; i++)
3670                         DMEMIT(" %s %s", __get_dev_name(rs->dev[i].meta_dev),
3671                                          __get_dev_name(rs->dev[i].data_dev));
3672                 break;
3673
3674         case STATUSTYPE_IMA:
3675                 rt = get_raid_type_by_ll(mddev->new_level, mddev->new_layout);
3676                 if (!rt)
3677                         return;
3678
3679                 DMEMIT_TARGET_NAME_VERSION(ti->type);
3680                 DMEMIT(",raid_type=%s,raid_disks=%d", rt->name, mddev->raid_disks);
3681
3682                 /* Access most recent mddev properties for status output */
3683                 smp_rmb();
3684                 recovery = rs->md.recovery;
3685                 state = decipher_sync_action(mddev, recovery);
3686                 DMEMIT(",raid_state=%s", sync_str(state));
3687
3688                 for (i = 0; i < rs->raid_disks; i++) {
3689                         DMEMIT(",raid_device_%d_status=", i);
3690                         DMEMIT(__raid_dev_status(rs, &rs->dev[i].rdev));
3691                 }
3692
3693                 if (rt_is_raid456(rt)) {
3694                         DMEMIT(",journal_dev_mode=");
3695                         switch (rs->journal_dev.mode) {
3696                         case R5C_JOURNAL_MODE_WRITE_THROUGH:
3697                                 DMEMIT("%s",
3698                                        _raid456_journal_mode[R5C_JOURNAL_MODE_WRITE_THROUGH].param);
3699                                 break;
3700                         case R5C_JOURNAL_MODE_WRITE_BACK:
3701                                 DMEMIT("%s",
3702                                        _raid456_journal_mode[R5C_JOURNAL_MODE_WRITE_BACK].param);
3703                                 break;
3704                         default:
3705                                 DMEMIT("invalid");
3706                                 break;
3707                         }
3708                 }
3709                 DMEMIT(";");
3710                 break;
3711         }
3712 }
3713
3714 static int raid_message(struct dm_target *ti, unsigned int argc, char **argv,
3715                         char *result, unsigned maxlen)
3716 {
3717         struct raid_set *rs = ti->private;
3718         struct mddev *mddev = &rs->md;
3719
3720         if (!mddev->pers || !mddev->pers->sync_request)
3721                 return -EINVAL;
3722
3723         if (!strcasecmp(argv[0], "frozen"))
3724                 set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
3725         else
3726                 clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
3727
3728         if (!strcasecmp(argv[0], "idle") || !strcasecmp(argv[0], "frozen")) {
3729                 if (mddev->sync_thread) {
3730                         set_bit(MD_RECOVERY_INTR, &mddev->recovery);
3731                         md_unregister_thread(&mddev->sync_thread);
3732                         md_reap_sync_thread(mddev);
3733                 }
3734         } else if (decipher_sync_action(mddev, mddev->recovery) != st_idle)
3735                 return -EBUSY;
3736         else if (!strcasecmp(argv[0], "resync"))
3737                 ; /* MD_RECOVERY_NEEDED set below */
3738         else if (!strcasecmp(argv[0], "recover"))
3739                 set_bit(MD_RECOVERY_RECOVER, &mddev->recovery);
3740         else {
3741                 if (!strcasecmp(argv[0], "check")) {
3742                         set_bit(MD_RECOVERY_CHECK, &mddev->recovery);
3743                         set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
3744                         set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
3745                 } else if (!strcasecmp(argv[0], "repair")) {
3746                         set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
3747                         set_bit(MD_RECOVERY_SYNC, &mddev->recovery);
3748                 } else
3749                         return -EINVAL;
3750         }
3751         if (mddev->ro == 2) {
3752                 /* A write to sync_action is enough to justify
3753                  * canceling read-auto mode
3754                  */
3755                 mddev->ro = 0;
3756                 if (!mddev->suspended && mddev->sync_thread)
3757                         md_wakeup_thread(mddev->sync_thread);
3758         }
3759         set_bit(MD_RECOVERY_NEEDED, &mddev->recovery);
3760         if (!mddev->suspended && mddev->thread)
3761                 md_wakeup_thread(mddev->thread);
3762
3763         return 0;
3764 }
3765
3766 static int raid_iterate_devices(struct dm_target *ti,
3767                                 iterate_devices_callout_fn fn, void *data)
3768 {
3769         struct raid_set *rs = ti->private;
3770         unsigned int i;
3771         int r = 0;
3772
3773         for (i = 0; !r && i < rs->raid_disks; i++) {
3774                 if (rs->dev[i].data_dev) {
3775                         r = fn(ti, rs->dev[i].data_dev,
3776                                0, /* No offset on data devs */
3777                                rs->md.dev_sectors, data);
3778                 }
3779         }
3780
3781         return r;
3782 }
3783
3784 static void raid_io_hints(struct dm_target *ti, struct queue_limits *limits)
3785 {
3786         struct raid_set *rs = ti->private;
3787         unsigned int chunk_size_bytes = to_bytes(rs->md.chunk_sectors);
3788
3789         blk_limits_io_min(limits, chunk_size_bytes);
3790         blk_limits_io_opt(limits, chunk_size_bytes * mddev_data_stripes(rs));
3791 }
3792
3793 static void raid_postsuspend(struct dm_target *ti)
3794 {
3795         struct raid_set *rs = ti->private;
3796
3797         if (!test_and_set_bit(RT_FLAG_RS_SUSPENDED, &rs->runtime_flags)) {
3798                 /* Writes have to be stopped before suspending to avoid deadlocks. */
3799                 if (!test_bit(MD_RECOVERY_FROZEN, &rs->md.recovery))
3800                         md_stop_writes(&rs->md);
3801
3802                 mddev_lock_nointr(&rs->md);
3803                 mddev_suspend(&rs->md);
3804                 mddev_unlock(&rs->md);
3805         }
3806 }
3807
3808 static void attempt_restore_of_faulty_devices(struct raid_set *rs)
3809 {
3810         int i;
3811         uint64_t cleared_failed_devices[DISKS_ARRAY_ELEMS];
3812         unsigned long flags;
3813         bool cleared = false;
3814         struct dm_raid_superblock *sb;
3815         struct mddev *mddev = &rs->md;
3816         struct md_rdev *r;
3817
3818         /* RAID personalities have to provide hot add/remove methods or we need to bail out. */
3819         if (!mddev->pers || !mddev->pers->hot_add_disk || !mddev->pers->hot_remove_disk)
3820                 return;
3821
3822         memset(cleared_failed_devices, 0, sizeof(cleared_failed_devices));
3823
3824         for (i = 0; i < rs->raid_disks; i++) {
3825                 r = &rs->dev[i].rdev;
3826                 /* HM FIXME: enhance journal device recovery processing */
3827                 if (test_bit(Journal, &r->flags))
3828                         continue;
3829
3830                 if (test_bit(Faulty, &r->flags) &&
3831                     r->meta_bdev && !read_disk_sb(r, r->sb_size, true)) {
3832                         DMINFO("Faulty %s device #%d has readable super block."
3833                                "  Attempting to revive it.",
3834                                rs->raid_type->name, i);
3835
3836                         /*
3837                          * Faulty bit may be set, but sometimes the array can
3838                          * be suspended before the personalities can respond
3839                          * by removing the device from the array (i.e. calling
3840                          * 'hot_remove_disk').  If they haven't yet removed
3841                          * the failed device, its 'raid_disk' number will be
3842                          * '>= 0' - meaning we must call this function
3843                          * ourselves.
3844                          */
3845                         flags = r->flags;
3846                         clear_bit(In_sync, &r->flags); /* Mandatory for hot remove. */
3847                         if (r->raid_disk >= 0) {
3848                                 if (mddev->pers->hot_remove_disk(mddev, r)) {
3849                                         /* Failed to revive this device, try next */
3850                                         r->flags = flags;
3851                                         continue;
3852                                 }
3853                         } else
3854                                 r->raid_disk = r->saved_raid_disk = i;
3855
3856                         clear_bit(Faulty, &r->flags);
3857                         clear_bit(WriteErrorSeen, &r->flags);
3858
3859                         if (mddev->pers->hot_add_disk(mddev, r)) {
3860                                 /* Failed to revive this device, try next */
3861                                 r->raid_disk = r->saved_raid_disk = -1;
3862                                 r->flags = flags;
3863                         } else {
3864                                 clear_bit(In_sync, &r->flags);
3865                                 r->recovery_offset = 0;
3866                                 set_bit(i, (void *) cleared_failed_devices);
3867                                 cleared = true;
3868                         }
3869                 }
3870         }
3871
3872         /* If any failed devices could be cleared, update all sbs failed_devices bits */
3873         if (cleared) {
3874                 uint64_t failed_devices[DISKS_ARRAY_ELEMS];
3875
3876                 rdev_for_each(r, &rs->md) {
3877                         if (test_bit(Journal, &r->flags))
3878                                 continue;
3879
3880                         sb = page_address(r->sb_page);
3881                         sb_retrieve_failed_devices(sb, failed_devices);
3882
3883                         for (i = 0; i < DISKS_ARRAY_ELEMS; i++)
3884                                 failed_devices[i] &= ~cleared_failed_devices[i];
3885
3886                         sb_update_failed_devices(sb, failed_devices);
3887                 }
3888         }
3889 }
3890
3891 static int __load_dirty_region_bitmap(struct raid_set *rs)
3892 {
3893         int r = 0;
3894
3895         /* Try loading the bitmap unless "raid0", which does not have one */
3896         if (!rs_is_raid0(rs) &&
3897             !test_and_set_bit(RT_FLAG_RS_BITMAP_LOADED, &rs->runtime_flags)) {
3898                 r = md_bitmap_load(&rs->md);
3899                 if (r)
3900                         DMERR("Failed to load bitmap");
3901         }
3902
3903         return r;
3904 }
3905
3906 /* Enforce updating all superblocks */
3907 static void rs_update_sbs(struct raid_set *rs)
3908 {
3909         struct mddev *mddev = &rs->md;
3910         int ro = mddev->ro;
3911
3912         set_bit(MD_SB_CHANGE_DEVS, &mddev->sb_flags);
3913         mddev->ro = 0;
3914         md_update_sb(mddev, 1);
3915         mddev->ro = ro;
3916 }
3917
3918 /*
3919  * Reshape changes raid algorithm of @rs to new one within personality
3920  * (e.g. raid6_zr -> raid6_nc), changes stripe size, adds/removes
3921  * disks from a raid set thus growing/shrinking it or resizes the set
3922  *
3923  * Call mddev_lock_nointr() before!
3924  */
3925 static int rs_start_reshape(struct raid_set *rs)
3926 {
3927         int r;
3928         struct mddev *mddev = &rs->md;
3929         struct md_personality *pers = mddev->pers;
3930
3931         /* Don't allow the sync thread to work until the table gets reloaded. */
3932         set_bit(MD_RECOVERY_WAIT, &mddev->recovery);
3933
3934         r = rs_setup_reshape(rs);
3935         if (r)
3936                 return r;
3937
3938         /*
3939          * Check any reshape constraints enforced by the personalility
3940          *
3941          * May as well already kick the reshape off so that * pers->start_reshape() becomes optional.
3942          */
3943         r = pers->check_reshape(mddev);
3944         if (r) {
3945                 rs->ti->error = "pers->check_reshape() failed";
3946                 return r;
3947         }
3948
3949         /*
3950          * Personality may not provide start reshape method in which
3951          * case check_reshape above has already covered everything
3952          */
3953         if (pers->start_reshape) {
3954                 r = pers->start_reshape(mddev);
3955                 if (r) {
3956                         rs->ti->error = "pers->start_reshape() failed";
3957                         return r;
3958                 }
3959         }
3960
3961         /*
3962          * Now reshape got set up, update superblocks to
3963          * reflect the fact so that a table reload will
3964          * access proper superblock content in the ctr.
3965          */
3966         rs_update_sbs(rs);
3967
3968         return 0;
3969 }
3970
3971 static int raid_preresume(struct dm_target *ti)
3972 {
3973         int r;
3974         struct raid_set *rs = ti->private;
3975         struct mddev *mddev = &rs->md;
3976
3977         /* This is a resume after a suspend of the set -> it's already started. */
3978         if (test_and_set_bit(RT_FLAG_RS_PRERESUMED, &rs->runtime_flags))
3979                 return 0;
3980
3981         /*
3982          * The superblocks need to be updated on disk if the
3983          * array is new or new devices got added (thus zeroed
3984          * out by userspace) or __load_dirty_region_bitmap
3985          * will overwrite them in core with old data or fail.
3986          */
3987         if (test_bit(RT_FLAG_UPDATE_SBS, &rs->runtime_flags))
3988                 rs_update_sbs(rs);
3989
3990         /* Load the bitmap from disk unless raid0 */
3991         r = __load_dirty_region_bitmap(rs);
3992         if (r)
3993                 return r;
3994
3995         /* We are extending the raid set size, adjust mddev/md_rdev sizes and set capacity. */
3996         if (test_bit(RT_FLAG_RS_GROW, &rs->runtime_flags)) {
3997                 mddev->array_sectors = rs->array_sectors;
3998                 mddev->dev_sectors = rs->dev_sectors;
3999                 rs_set_rdev_sectors(rs);
4000                 rs_set_capacity(rs);
4001         }
4002
4003         /* Resize bitmap to adjust to changed region size (aka MD bitmap chunksize) or grown device size */
4004         if (test_bit(RT_FLAG_RS_BITMAP_LOADED, &rs->runtime_flags) && mddev->bitmap &&
4005             (test_bit(RT_FLAG_RS_GROW, &rs->runtime_flags) ||
4006              (rs->requested_bitmap_chunk_sectors &&
4007                mddev->bitmap_info.chunksize != to_bytes(rs->requested_bitmap_chunk_sectors)))) {
4008                 int chunksize = to_bytes(rs->requested_bitmap_chunk_sectors) ?: mddev->bitmap_info.chunksize;
4009
4010                 r = md_bitmap_resize(mddev->bitmap, mddev->dev_sectors, chunksize, 0);
4011                 if (r)
4012                         DMERR("Failed to resize bitmap");
4013         }
4014
4015         /* Check for any resize/reshape on @rs and adjust/initiate */
4016         /* Be prepared for mddev_resume() in raid_resume() */
4017         set_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
4018         if (mddev->recovery_cp && mddev->recovery_cp < MaxSector) {
4019                 set_bit(MD_RECOVERY_REQUESTED, &mddev->recovery);
4020                 mddev->resync_min = mddev->recovery_cp;
4021                 if (test_bit(RT_FLAG_RS_GROW, &rs->runtime_flags))
4022                         mddev->resync_max_sectors = mddev->dev_sectors;
4023         }
4024
4025         /* Check for any reshape request unless new raid set */
4026         if (test_bit(RT_FLAG_RESHAPE_RS, &rs->runtime_flags)) {
4027                 /* Initiate a reshape. */
4028                 rs_set_rdev_sectors(rs);
4029                 mddev_lock_nointr(mddev);
4030                 r = rs_start_reshape(rs);
4031                 mddev_unlock(mddev);
4032                 if (r)
4033                         DMWARN("Failed to check/start reshape, continuing without change");
4034                 r = 0;
4035         }
4036
4037         return r;
4038 }
4039
4040 static void raid_resume(struct dm_target *ti)
4041 {
4042         struct raid_set *rs = ti->private;
4043         struct mddev *mddev = &rs->md;
4044
4045         if (test_and_set_bit(RT_FLAG_RS_RESUMED, &rs->runtime_flags)) {
4046                 /*
4047                  * A secondary resume while the device is active.
4048                  * Take this opportunity to check whether any failed
4049                  * devices are reachable again.
4050                  */
4051                 attempt_restore_of_faulty_devices(rs);
4052         }
4053
4054         if (test_and_clear_bit(RT_FLAG_RS_SUSPENDED, &rs->runtime_flags)) {
4055                 /* Only reduce raid set size before running a disk removing reshape. */
4056                 if (mddev->delta_disks < 0)
4057                         rs_set_capacity(rs);
4058
4059                 mddev_lock_nointr(mddev);
4060                 clear_bit(MD_RECOVERY_FROZEN, &mddev->recovery);
4061                 mddev->ro = 0;
4062                 mddev->in_sync = 0;
4063                 mddev_resume(mddev);
4064                 mddev_unlock(mddev);
4065         }
4066 }
4067
4068 static struct target_type raid_target = {
4069         .name = "raid",
4070         .version = {1, 15, 1},
4071         .module = THIS_MODULE,
4072         .ctr = raid_ctr,
4073         .dtr = raid_dtr,
4074         .map = raid_map,
4075         .status = raid_status,
4076         .message = raid_message,
4077         .iterate_devices = raid_iterate_devices,
4078         .io_hints = raid_io_hints,
4079         .postsuspend = raid_postsuspend,
4080         .preresume = raid_preresume,
4081         .resume = raid_resume,
4082 };
4083
4084 static int __init dm_raid_init(void)
4085 {
4086         DMINFO("Loading target version %u.%u.%u",
4087                raid_target.version[0],
4088                raid_target.version[1],
4089                raid_target.version[2]);
4090         return dm_register_target(&raid_target);
4091 }
4092
4093 static void __exit dm_raid_exit(void)
4094 {
4095         dm_unregister_target(&raid_target);
4096 }
4097
4098 module_init(dm_raid_init);
4099 module_exit(dm_raid_exit);
4100
4101 module_param(devices_handle_discard_safely, bool, 0644);
4102 MODULE_PARM_DESC(devices_handle_discard_safely,
4103                  "Set to Y if all devices in each array reliably return zeroes on reads from discarded regions");
4104
4105 MODULE_DESCRIPTION(DM_NAME " raid0/1/10/4/5/6 target");
4106 MODULE_ALIAS("dm-raid0");
4107 MODULE_ALIAS("dm-raid1");
4108 MODULE_ALIAS("dm-raid10");
4109 MODULE_ALIAS("dm-raid4");
4110 MODULE_ALIAS("dm-raid5");
4111 MODULE_ALIAS("dm-raid6");
4112 MODULE_AUTHOR("Neil Brown <dm-devel@redhat.com>");
4113 MODULE_AUTHOR("Heinz Mauelshagen <dm-devel@redhat.com>");
4114 MODULE_LICENSE("GPL");