drivers/md/dm-raid.c

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