drivers/md/dm-zoned-metadata.c

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This source file includes following definitions.
dmz_id
dmz_start_sect
dmz_start_block
dmz_nr_chunks
dmz_nr_rnd_zones
dmz_nr_unmap_rnd_zones
dmz_lock_map
dmz_unlock_map
dmz_lock_metadata
dmz_unlock_metadata
dmz_lock_flush
dmz_unlock_flush
dmz_alloc_mblock
dmz_free_mblock
dmz_insert_mblock
dmz_get_mblock_fast
dmz_mblock_bio_end_io
dmz_get_mblock_slow
dmz_shrink_mblock_cache
dmz_mblock_shrinker_count
dmz_mblock_shrinker_scan
dmz_release_mblock
dmz_get_mblock
dmz_dirty_mblock
dmz_write_mblock
dmz_rdwr_block
dmz_write_sb
dmz_write_dirty_mblocks
dmz_log_dirty_mblocks
dmz_flush_metadata
dmz_check_sb
dmz_read_sb
dmz_lookup_secondary_sb
dmz_get_sb
dmz_recover_mblocks
dmz_load_sb
dmz_init_zone
dmz_drop_zones
dmz_init_zones
dmz_update_zone
dmz_handle_seq_write_err
dmz_get
dmz_reset_zone
dmz_load_mapping
dmz_set_chunk_mapping
__dmz_lru_zone
dmz_lru_zone
dmz_wait_for_free_zones
dmz_lock_zone_reclaim
dmz_unlock_zone_reclaim
dmz_wait_for_reclaim
dmz_get_rnd_zone_for_reclaim
dmz_get_seq_zone_for_reclaim
dmz_get_zone_for_reclaim
dmz_get_chunk_mapping
dmz_put_chunk_mapping
dmz_get_chunk_buffer
dmz_alloc_zone
dmz_free_zone
dmz_map_zone
dmz_unmap_zone
dmz_set_bits
dmz_get_bitmap
dmz_copy_valid_blocks
dmz_merge_valid_blocks
dmz_validate_blocks
dmz_clear_bits
dmz_invalidate_blocks
dmz_test_block
dmz_to_next_set_block
dmz_block_valid
dmz_first_valid_block
dmz_count_bits
dmz_get_zone_weight
dmz_cleanup_metadata
dmz_ctr_metadata
dmz_dtr_metadata
dmz_resume_metadata
   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2017 Western Digital Corporation or its affiliates.
   4  *
   5  * This file is released under the GPL.
   6  */
   7 
   8 #include "dm-zoned.h"
   9 
  10 #include <linux/module.h>
  11 #include <linux/crc32.h>
  12 #include <linux/sched/mm.h>
  13 
  14 #define DM_MSG_PREFIX           "zoned metadata"
  15 
  16 /*
  17  * Metadata version.
  18  */
  19 #define DMZ_META_VER    1
  20 
  21 /*
  22  * On-disk super block magic.
  23  */
  24 #define DMZ_MAGIC       ((((unsigned int)('D')) << 24) | \
  25                          (((unsigned int)('Z')) << 16) | \
  26                          (((unsigned int)('B')) <<  8) | \
  27                          ((unsigned int)('D')))
  28 
  29 /*
  30  * On disk super block.
  31  * This uses only 512 B but uses on disk a full 4KB block. This block is
  32  * followed on disk by the mapping table of chunks to zones and the bitmap
  33  * blocks indicating zone block validity.
  34  * The overall resulting metadata format is:
  35  *    (1) Super block (1 block)
  36  *    (2) Chunk mapping table (nr_map_blocks)
  37  *    (3) Bitmap blocks (nr_bitmap_blocks)
  38  * All metadata blocks are stored in conventional zones, starting from
  39  * the first conventional zone found on disk.
  40  */
  41 struct dmz_super {
  42         /* Magic number */
  43         __le32          magic;                  /*   4 */
  44 
  45         /* Metadata version number */
  46         __le32          version;                /*   8 */
  47 
  48         /* Generation number */
  49         __le64          gen;                    /*  16 */
  50 
  51         /* This block number */
  52         __le64          sb_block;               /*  24 */
  53 
  54         /* The number of metadata blocks, including this super block */
  55         __le32          nr_meta_blocks;         /*  28 */
  56 
  57         /* The number of sequential zones reserved for reclaim */
  58         __le32          nr_reserved_seq;        /*  32 */
  59 
  60         /* The number of entries in the mapping table */
  61         __le32          nr_chunks;              /*  36 */
  62 
  63         /* The number of blocks used for the chunk mapping table */
  64         __le32          nr_map_blocks;          /*  40 */
  65 
  66         /* The number of blocks used for the block bitmaps */
  67         __le32          nr_bitmap_blocks;       /*  44 */
  68 
  69         /* Checksum */
  70         __le32          crc;                    /*  48 */
  71 
  72         /* Padding to full 512B sector */
  73         u8              reserved[464];          /* 512 */
  74 };
  75 
  76 /*
  77  * Chunk mapping entry: entries are indexed by chunk number
  78  * and give the zone ID (dzone_id) mapping the chunk on disk.
  79  * This zone may be sequential or random. If it is a sequential
  80  * zone, a second zone (bzone_id) used as a write buffer may
  81  * also be specified. This second zone will always be a randomly
  82  * writeable zone.
  83  */
  84 struct dmz_map {
  85         __le32                  dzone_id;
  86         __le32                  bzone_id;
  87 };
  88 
  89 /*
  90  * Chunk mapping table metadata: 512 8-bytes entries per 4KB block.
  91  */
  92 #define DMZ_MAP_ENTRIES         (DMZ_BLOCK_SIZE / sizeof(struct dmz_map))
  93 #define DMZ_MAP_ENTRIES_SHIFT   (ilog2(DMZ_MAP_ENTRIES))
  94 #define DMZ_MAP_ENTRIES_MASK    (DMZ_MAP_ENTRIES - 1)
  95 #define DMZ_MAP_UNMAPPED        UINT_MAX
  96 
  97 /*
  98  * Meta data block descriptor (for cached metadata blocks).
  99  */
 100 struct dmz_mblock {
 101         struct rb_node          node;
 102         struct list_head        link;
 103         sector_t                no;
 104         unsigned int            ref;
 105         unsigned long           state;
 106         struct page             *page;
 107         void                    *data;
 108 };
 109 
 110 /*
 111  * Metadata block state flags.
 112  */
 113 enum {
 114         DMZ_META_DIRTY,
 115         DMZ_META_READING,
 116         DMZ_META_WRITING,
 117         DMZ_META_ERROR,
 118 };
 119 
 120 /*
 121  * Super block information (one per metadata set).
 122  */
 123 struct dmz_sb {
 124         sector_t                block;
 125         struct dmz_mblock       *mblk;
 126         struct dmz_super        *sb;
 127 };
 128 
 129 /*
 130  * In-memory metadata.
 131  */
 132 struct dmz_metadata {
 133         struct dmz_dev          *dev;
 134 
 135         sector_t                zone_bitmap_size;
 136         unsigned int            zone_nr_bitmap_blocks;
 137         unsigned int            zone_bits_per_mblk;
 138 
 139         unsigned int            nr_bitmap_blocks;
 140         unsigned int            nr_map_blocks;
 141 
 142         unsigned int            nr_useable_zones;
 143         unsigned int            nr_meta_blocks;
 144         unsigned int            nr_meta_zones;
 145         unsigned int            nr_data_zones;
 146         unsigned int            nr_rnd_zones;
 147         unsigned int            nr_reserved_seq;
 148         unsigned int            nr_chunks;
 149 
 150         /* Zone information array */
 151         struct dm_zone          *zones;
 152 
 153         struct dm_zone          *sb_zone;
 154         struct dmz_sb           sb[2];
 155         unsigned int            mblk_primary;
 156         u64                     sb_gen;
 157         unsigned int            min_nr_mblks;
 158         unsigned int            max_nr_mblks;
 159         atomic_t                nr_mblks;
 160         struct rw_semaphore     mblk_sem;
 161         struct mutex            mblk_flush_lock;
 162         spinlock_t              mblk_lock;
 163         struct rb_root          mblk_rbtree;
 164         struct list_head        mblk_lru_list;
 165         struct list_head        mblk_dirty_list;
 166         struct shrinker         mblk_shrinker;
 167 
 168         /* Zone allocation management */
 169         struct mutex            map_lock;
 170         struct dmz_mblock       **map_mblk;
 171         unsigned int            nr_rnd;
 172         atomic_t                unmap_nr_rnd;
 173         struct list_head        unmap_rnd_list;
 174         struct list_head        map_rnd_list;
 175 
 176         unsigned int            nr_seq;
 177         atomic_t                unmap_nr_seq;
 178         struct list_head        unmap_seq_list;
 179         struct list_head        map_seq_list;
 180 
 181         atomic_t                nr_reserved_seq_zones;
 182         struct list_head        reserved_seq_zones_list;
 183 
 184         wait_queue_head_t       free_wq;
 185 };
 186 
 187 /*
 188  * Various accessors
 189  */
 190 unsigned int dmz_id(struct dmz_metadata *zmd, struct dm_zone *zone)
 191 {
 192         return ((unsigned int)(zone - zmd->zones));
 193 }
 194 
 195 sector_t dmz_start_sect(struct dmz_metadata *zmd, struct dm_zone *zone)
 196 {
 197         return (sector_t)dmz_id(zmd, zone) << zmd->dev->zone_nr_sectors_shift;
 198 }
 199 
 200 sector_t dmz_start_block(struct dmz_metadata *zmd, struct dm_zone *zone)
 201 {
 202         return (sector_t)dmz_id(zmd, zone) << zmd->dev->zone_nr_blocks_shift;
 203 }
 204 
 205 unsigned int dmz_nr_chunks(struct dmz_metadata *zmd)
 206 {
 207         return zmd->nr_chunks;
 208 }
 209 
 210 unsigned int dmz_nr_rnd_zones(struct dmz_metadata *zmd)
 211 {
 212         return zmd->nr_rnd;
 213 }
 214 
 215 unsigned int dmz_nr_unmap_rnd_zones(struct dmz_metadata *zmd)
 216 {
 217         return atomic_read(&zmd->unmap_nr_rnd);
 218 }
 219 
 220 /*
 221  * Lock/unlock mapping table.
 222  * The map lock also protects all the zone lists.
 223  */
 224 void dmz_lock_map(struct dmz_metadata *zmd)
 225 {
 226         mutex_lock(&zmd->map_lock);
 227 }
 228 
 229 void dmz_unlock_map(struct dmz_metadata *zmd)
 230 {
 231         mutex_unlock(&zmd->map_lock);
 232 }
 233 
 234 /*
 235  * Lock/unlock metadata access. This is a "read" lock on a semaphore
 236  * that prevents metadata flush from running while metadata are being
 237  * modified. The actual metadata write mutual exclusion is achieved with
 238  * the map lock and zone state management (active and reclaim state are
 239  * mutually exclusive).
 240  */
 241 void dmz_lock_metadata(struct dmz_metadata *zmd)
 242 {
 243         down_read(&zmd->mblk_sem);
 244 }
 245 
 246 void dmz_unlock_metadata(struct dmz_metadata *zmd)
 247 {
 248         up_read(&zmd->mblk_sem);
 249 }
 250 
 251 /*
 252  * Lock/unlock flush: prevent concurrent executions
 253  * of dmz_flush_metadata as well as metadata modification in reclaim
 254  * while flush is being executed.
 255  */
 256 void dmz_lock_flush(struct dmz_metadata *zmd)
 257 {
 258         mutex_lock(&zmd->mblk_flush_lock);
 259 }
 260 
 261 void dmz_unlock_flush(struct dmz_metadata *zmd)
 262 {
 263         mutex_unlock(&zmd->mblk_flush_lock);
 264 }
 265 
 266 /*
 267  * Allocate a metadata block.
 268  */
 269 static struct dmz_mblock *dmz_alloc_mblock(struct dmz_metadata *zmd,
 270                                            sector_t mblk_no)
 271 {
 272         struct dmz_mblock *mblk = NULL;
 273 
 274         /* See if we can reuse cached blocks */
 275         if (zmd->max_nr_mblks && atomic_read(&zmd->nr_mblks) > zmd->max_nr_mblks) {
 276                 spin_lock(&zmd->mblk_lock);
 277                 mblk = list_first_entry_or_null(&zmd->mblk_lru_list,
 278                                                 struct dmz_mblock, link);
 279                 if (mblk) {
 280                         list_del_init(&mblk->link);
 281                         rb_erase(&mblk->node, &zmd->mblk_rbtree);
 282                         mblk->no = mblk_no;
 283                 }
 284                 spin_unlock(&zmd->mblk_lock);
 285                 if (mblk)
 286                         return mblk;
 287         }
 288 
 289         /* Allocate a new block */
 290         mblk = kmalloc(sizeof(struct dmz_mblock), GFP_NOIO);
 291         if (!mblk)
 292                 return NULL;
 293 
 294         mblk->page = alloc_page(GFP_NOIO);
 295         if (!mblk->page) {
 296                 kfree(mblk);
 297                 return NULL;
 298         }
 299 
 300         RB_CLEAR_NODE(&mblk->node);
 301         INIT_LIST_HEAD(&mblk->link);
 302         mblk->ref = 0;
 303         mblk->state = 0;
 304         mblk->no = mblk_no;
 305         mblk->data = page_address(mblk->page);
 306 
 307         atomic_inc(&zmd->nr_mblks);
 308 
 309         return mblk;
 310 }
 311 
 312 /*
 313  * Free a metadata block.
 314  */
 315 static void dmz_free_mblock(struct dmz_metadata *zmd, struct dmz_mblock *mblk)
 316 {
 317         __free_pages(mblk->page, 0);
 318         kfree(mblk);
 319 
 320         atomic_dec(&zmd->nr_mblks);
 321 }
 322 
 323 /*
 324  * Insert a metadata block in the rbtree.
 325  */
 326 static void dmz_insert_mblock(struct dmz_metadata *zmd, struct dmz_mblock *mblk)
 327 {
 328         struct rb_root *root = &zmd->mblk_rbtree;
 329         struct rb_node **new = &(root->rb_node), *parent = NULL;
 330         struct dmz_mblock *b;
 331 
 332         /* Figure out where to put the new node */
 333         while (*new) {
 334                 b = container_of(*new, struct dmz_mblock, node);
 335                 parent = *new;
 336                 new = (b->no < mblk->no) ? &((*new)->rb_left) : &((*new)->rb_right);
 337         }
 338 
 339         /* Add new node and rebalance tree */
 340         rb_link_node(&mblk->node, parent, new);
 341         rb_insert_color(&mblk->node, root);
 342 }
 343 
 344 /*
 345  * Lookup a metadata block in the rbtree. If the block is found, increment
 346  * its reference count.
 347  */
 348 static struct dmz_mblock *dmz_get_mblock_fast(struct dmz_metadata *zmd,
 349                                               sector_t mblk_no)
 350 {
 351         struct rb_root *root = &zmd->mblk_rbtree;
 352         struct rb_node *node = root->rb_node;
 353         struct dmz_mblock *mblk;
 354 
 355         while (node) {
 356                 mblk = container_of(node, struct dmz_mblock, node);
 357                 if (mblk->no == mblk_no) {
 358                         /*
 359                          * If this is the first reference to the block,
 360                          * remove it from the LRU list.
 361                          */
 362                         mblk->ref++;
 363                         if (mblk->ref == 1 &&
 364                             !test_bit(DMZ_META_DIRTY, &mblk->state))
 365                                 list_del_init(&mblk->link);
 366                         return mblk;
 367                 }
 368                 node = (mblk->no < mblk_no) ? node->rb_left : node->rb_right;
 369         }
 370 
 371         return NULL;
 372 }
 373 
 374 /*
 375  * Metadata block BIO end callback.
 376  */
 377 static void dmz_mblock_bio_end_io(struct bio *bio)
 378 {
 379         struct dmz_mblock *mblk = bio->bi_private;
 380         int flag;
 381 
 382         if (bio->bi_status)
 383                 set_bit(DMZ_META_ERROR, &mblk->state);
 384 
 385         if (bio_op(bio) == REQ_OP_WRITE)
 386                 flag = DMZ_META_WRITING;
 387         else
 388                 flag = DMZ_META_READING;
 389 
 390         clear_bit_unlock(flag, &mblk->state);
 391         smp_mb__after_atomic();
 392         wake_up_bit(&mblk->state, flag);
 393 
 394         bio_put(bio);
 395 }
 396 
 397 /*
 398  * Read an uncached metadata block from disk and add it to the cache.
 399  */
 400 static struct dmz_mblock *dmz_get_mblock_slow(struct dmz_metadata *zmd,
 401                                               sector_t mblk_no)
 402 {
 403         struct dmz_mblock *mblk, *m;
 404         sector_t block = zmd->sb[zmd->mblk_primary].block + mblk_no;
 405         struct bio *bio;
 406 
 407         if (dmz_bdev_is_dying(zmd->dev))
 408                 return ERR_PTR(-EIO);
 409 
 410         /* Get a new block and a BIO to read it */
 411         mblk = dmz_alloc_mblock(zmd, mblk_no);
 412         if (!mblk)
 413                 return ERR_PTR(-ENOMEM);
 414 
 415         bio = bio_alloc(GFP_NOIO, 1);
 416         if (!bio) {
 417                 dmz_free_mblock(zmd, mblk);
 418                 return ERR_PTR(-ENOMEM);
 419         }
 420 
 421         spin_lock(&zmd->mblk_lock);
 422 
 423         /*
 424          * Make sure that another context did not start reading
 425          * the block already.
 426          */
 427         m = dmz_get_mblock_fast(zmd, mblk_no);
 428         if (m) {
 429                 spin_unlock(&zmd->mblk_lock);
 430                 dmz_free_mblock(zmd, mblk);
 431                 bio_put(bio);
 432                 return m;
 433         }
 434 
 435         mblk->ref++;
 436         set_bit(DMZ_META_READING, &mblk->state);
 437         dmz_insert_mblock(zmd, mblk);
 438 
 439         spin_unlock(&zmd->mblk_lock);
 440 
 441         /* Submit read BIO */
 442         bio->bi_iter.bi_sector = dmz_blk2sect(block);
 443         bio_set_dev(bio, zmd->dev->bdev);
 444         bio->bi_private = mblk;
 445         bio->bi_end_io = dmz_mblock_bio_end_io;
 446         bio_set_op_attrs(bio, REQ_OP_READ, REQ_META | REQ_PRIO);
 447         bio_add_page(bio, mblk->page, DMZ_BLOCK_SIZE, 0);
 448         submit_bio(bio);
 449 
 450         return mblk;
 451 }
 452 
 453 /*
 454  * Free metadata blocks.
 455  */
 456 static unsigned long dmz_shrink_mblock_cache(struct dmz_metadata *zmd,
 457                                              unsigned long limit)
 458 {
 459         struct dmz_mblock *mblk;
 460         unsigned long count = 0;
 461 
 462         if (!zmd->max_nr_mblks)
 463                 return 0;
 464 
 465         while (!list_empty(&zmd->mblk_lru_list) &&
 466                atomic_read(&zmd->nr_mblks) > zmd->min_nr_mblks &&
 467                count < limit) {
 468                 mblk = list_first_entry(&zmd->mblk_lru_list,
 469                                         struct dmz_mblock, link);
 470                 list_del_init(&mblk->link);
 471                 rb_erase(&mblk->node, &zmd->mblk_rbtree);
 472                 dmz_free_mblock(zmd, mblk);
 473                 count++;
 474         }
 475 
 476         return count;
 477 }
 478 
 479 /*
 480  * For mblock shrinker: get the number of unused metadata blocks in the cache.
 481  */
 482 static unsigned long dmz_mblock_shrinker_count(struct shrinker *shrink,
 483                                                struct shrink_control *sc)
 484 {
 485         struct dmz_metadata *zmd = container_of(shrink, struct dmz_metadata, mblk_shrinker);
 486 
 487         return atomic_read(&zmd->nr_mblks);
 488 }
 489 
 490 /*
 491  * For mblock shrinker: scan unused metadata blocks and shrink the cache.
 492  */
 493 static unsigned long dmz_mblock_shrinker_scan(struct shrinker *shrink,
 494                                               struct shrink_control *sc)
 495 {
 496         struct dmz_metadata *zmd = container_of(shrink, struct dmz_metadata, mblk_shrinker);
 497         unsigned long count;
 498 
 499         spin_lock(&zmd->mblk_lock);
 500         count = dmz_shrink_mblock_cache(zmd, sc->nr_to_scan);
 501         spin_unlock(&zmd->mblk_lock);
 502 
 503         return count ? count : SHRINK_STOP;
 504 }
 505 
 506 /*
 507  * Release a metadata block.
 508  */
 509 static void dmz_release_mblock(struct dmz_metadata *zmd,
 510                                struct dmz_mblock *mblk)
 511 {
 512 
 513         if (!mblk)
 514                 return;
 515 
 516         spin_lock(&zmd->mblk_lock);
 517 
 518         mblk->ref--;
 519         if (mblk->ref == 0) {
 520                 if (test_bit(DMZ_META_ERROR, &mblk->state)) {
 521                         rb_erase(&mblk->node, &zmd->mblk_rbtree);
 522                         dmz_free_mblock(zmd, mblk);
 523                 } else if (!test_bit(DMZ_META_DIRTY, &mblk->state)) {
 524                         list_add_tail(&mblk->link, &zmd->mblk_lru_list);
 525                         dmz_shrink_mblock_cache(zmd, 1);
 526                 }
 527         }
 528 
 529         spin_unlock(&zmd->mblk_lock);
 530 }
 531 
 532 /*
 533  * Get a metadata block from the rbtree. If the block
 534  * is not present, read it from disk.
 535  */
 536 static struct dmz_mblock *dmz_get_mblock(struct dmz_metadata *zmd,
 537                                          sector_t mblk_no)
 538 {
 539         struct dmz_mblock *mblk;
 540 
 541         /* Check rbtree */
 542         spin_lock(&zmd->mblk_lock);
 543         mblk = dmz_get_mblock_fast(zmd, mblk_no);
 544         spin_unlock(&zmd->mblk_lock);
 545 
 546         if (!mblk) {
 547                 /* Cache miss: read the block from disk */
 548                 mblk = dmz_get_mblock_slow(zmd, mblk_no);
 549                 if (IS_ERR(mblk))
 550                         return mblk;
 551         }
 552 
 553         /* Wait for on-going read I/O and check for error */
 554         wait_on_bit_io(&mblk->state, DMZ_META_READING,
 555                        TASK_UNINTERRUPTIBLE);
 556         if (test_bit(DMZ_META_ERROR, &mblk->state)) {
 557                 dmz_release_mblock(zmd, mblk);
 558                 dmz_check_bdev(zmd->dev);
 559                 return ERR_PTR(-EIO);
 560         }
 561 
 562         return mblk;
 563 }
 564 
 565 /*
 566  * Mark a metadata block dirty.
 567  */
 568 static void dmz_dirty_mblock(struct dmz_metadata *zmd, struct dmz_mblock *mblk)
 569 {
 570         spin_lock(&zmd->mblk_lock);
 571         if (!test_and_set_bit(DMZ_META_DIRTY, &mblk->state))
 572                 list_add_tail(&mblk->link, &zmd->mblk_dirty_list);
 573         spin_unlock(&zmd->mblk_lock);
 574 }
 575 
 576 /*
 577  * Issue a metadata block write BIO.
 578  */
 579 static int dmz_write_mblock(struct dmz_metadata *zmd, struct dmz_mblock *mblk,
 580                             unsigned int set)
 581 {
 582         sector_t block = zmd->sb[set].block + mblk->no;
 583         struct bio *bio;
 584 
 585         if (dmz_bdev_is_dying(zmd->dev))
 586                 return -EIO;
 587 
 588         bio = bio_alloc(GFP_NOIO, 1);
 589         if (!bio) {
 590                 set_bit(DMZ_META_ERROR, &mblk->state);
 591                 return -ENOMEM;
 592         }
 593 
 594         set_bit(DMZ_META_WRITING, &mblk->state);
 595 
 596         bio->bi_iter.bi_sector = dmz_blk2sect(block);
 597         bio_set_dev(bio, zmd->dev->bdev);
 598         bio->bi_private = mblk;
 599         bio->bi_end_io = dmz_mblock_bio_end_io;
 600         bio_set_op_attrs(bio, REQ_OP_WRITE, REQ_META | REQ_PRIO);
 601         bio_add_page(bio, mblk->page, DMZ_BLOCK_SIZE, 0);
 602         submit_bio(bio);
 603 
 604         return 0;
 605 }
 606 
 607 /*
 608  * Read/write a metadata block.
 609  */
 610 static int dmz_rdwr_block(struct dmz_metadata *zmd, int op, sector_t block,
 611                           struct page *page)
 612 {
 613         struct bio *bio;
 614         int ret;
 615 
 616         if (dmz_bdev_is_dying(zmd->dev))
 617                 return -EIO;
 618 
 619         bio = bio_alloc(GFP_NOIO, 1);
 620         if (!bio)
 621                 return -ENOMEM;
 622 
 623         bio->bi_iter.bi_sector = dmz_blk2sect(block);
 624         bio_set_dev(bio, zmd->dev->bdev);
 625         bio_set_op_attrs(bio, op, REQ_SYNC | REQ_META | REQ_PRIO);
 626         bio_add_page(bio, page, DMZ_BLOCK_SIZE, 0);
 627         ret = submit_bio_wait(bio);
 628         bio_put(bio);
 629 
 630         if (ret)
 631                 dmz_check_bdev(zmd->dev);
 632         return ret;
 633 }
 634 
 635 /*
 636  * Write super block of the specified metadata set.
 637  */
 638 static int dmz_write_sb(struct dmz_metadata *zmd, unsigned int set)
 639 {
 640         sector_t block = zmd->sb[set].block;
 641         struct dmz_mblock *mblk = zmd->sb[set].mblk;
 642         struct dmz_super *sb = zmd->sb[set].sb;
 643         u64 sb_gen = zmd->sb_gen + 1;
 644         int ret;
 645 
 646         sb->magic = cpu_to_le32(DMZ_MAGIC);
 647         sb->version = cpu_to_le32(DMZ_META_VER);
 648 
 649         sb->gen = cpu_to_le64(sb_gen);
 650 
 651         sb->sb_block = cpu_to_le64(block);
 652         sb->nr_meta_blocks = cpu_to_le32(zmd->nr_meta_blocks);
 653         sb->nr_reserved_seq = cpu_to_le32(zmd->nr_reserved_seq);
 654         sb->nr_chunks = cpu_to_le32(zmd->nr_chunks);
 655 
 656         sb->nr_map_blocks = cpu_to_le32(zmd->nr_map_blocks);
 657         sb->nr_bitmap_blocks = cpu_to_le32(zmd->nr_bitmap_blocks);
 658 
 659         sb->crc = 0;
 660         sb->crc = cpu_to_le32(crc32_le(sb_gen, (unsigned char *)sb, DMZ_BLOCK_SIZE));
 661 
 662         ret = dmz_rdwr_block(zmd, REQ_OP_WRITE, block, mblk->page);
 663         if (ret == 0)
 664                 ret = blkdev_issue_flush(zmd->dev->bdev, GFP_NOIO, NULL);
 665 
 666         return ret;
 667 }
 668 
 669 /*
 670  * Write dirty metadata blocks to the specified set.
 671  */
 672 static int dmz_write_dirty_mblocks(struct dmz_metadata *zmd,
 673                                    struct list_head *write_list,
 674                                    unsigned int set)
 675 {
 676         struct dmz_mblock *mblk;
 677         struct blk_plug plug;
 678         int ret = 0, nr_mblks_submitted = 0;
 679 
 680         /* Issue writes */
 681         blk_start_plug(&plug);
 682         list_for_each_entry(mblk, write_list, link) {
 683                 ret = dmz_write_mblock(zmd, mblk, set);
 684                 if (ret)
 685                         break;
 686                 nr_mblks_submitted++;
 687         }
 688         blk_finish_plug(&plug);
 689 
 690         /* Wait for completion */
 691         list_for_each_entry(mblk, write_list, link) {
 692                 if (!nr_mblks_submitted)
 693                         break;
 694                 wait_on_bit_io(&mblk->state, DMZ_META_WRITING,
 695                                TASK_UNINTERRUPTIBLE);
 696                 if (test_bit(DMZ_META_ERROR, &mblk->state)) {
 697                         clear_bit(DMZ_META_ERROR, &mblk->state);
 698                         dmz_check_bdev(zmd->dev);
 699                         ret = -EIO;
 700                 }
 701                 nr_mblks_submitted--;
 702         }
 703 
 704         /* Flush drive cache (this will also sync data) */
 705         if (ret == 0)
 706                 ret = blkdev_issue_flush(zmd->dev->bdev, GFP_NOIO, NULL);
 707 
 708         return ret;
 709 }
 710 
 711 /*
 712  * Log dirty metadata blocks.
 713  */
 714 static int dmz_log_dirty_mblocks(struct dmz_metadata *zmd,
 715                                  struct list_head *write_list)
 716 {
 717         unsigned int log_set = zmd->mblk_primary ^ 0x1;
 718         int ret;
 719 
 720         /* Write dirty blocks to the log */
 721         ret = dmz_write_dirty_mblocks(zmd, write_list, log_set);
 722         if (ret)
 723                 return ret;
 724 
 725         /*
 726          * No error so far: now validate the log by updating the
 727          * log index super block generation.
 728          */
 729         ret = dmz_write_sb(zmd, log_set);
 730         if (ret)
 731                 return ret;
 732 
 733         return 0;
 734 }
 735 
 736 /*
 737  * Flush dirty metadata blocks.
 738  */
 739 int dmz_flush_metadata(struct dmz_metadata *zmd)
 740 {
 741         struct dmz_mblock *mblk;
 742         struct list_head write_list;
 743         int ret;
 744 
 745         if (WARN_ON(!zmd))
 746                 return 0;
 747 
 748         INIT_LIST_HEAD(&write_list);
 749 
 750         /*
 751          * Make sure that metadata blocks are stable before logging: take
 752          * the write lock on the metadata semaphore to prevent target BIOs
 753          * from modifying metadata.
 754          */
 755         down_write(&zmd->mblk_sem);
 756 
 757         /*
 758          * This is called from the target flush work and reclaim work.
 759          * Concurrent execution is not allowed.
 760          */
 761         dmz_lock_flush(zmd);
 762 
 763         if (dmz_bdev_is_dying(zmd->dev)) {
 764                 ret = -EIO;
 765                 goto out;
 766         }
 767 
 768         /* Get dirty blocks */
 769         spin_lock(&zmd->mblk_lock);
 770         list_splice_init(&zmd->mblk_dirty_list, &write_list);
 771         spin_unlock(&zmd->mblk_lock);
 772 
 773         /* If there are no dirty metadata blocks, just flush the device cache */
 774         if (list_empty(&write_list)) {
 775                 ret = blkdev_issue_flush(zmd->dev->bdev, GFP_NOIO, NULL);
 776                 goto err;
 777         }
 778 
 779         /*
 780          * The primary metadata set is still clean. Keep it this way until
 781          * all updates are successful in the secondary set. That is, use
 782          * the secondary set as a log.
 783          */
 784         ret = dmz_log_dirty_mblocks(zmd, &write_list);
 785         if (ret)
 786                 goto err;
 787 
 788         /*
 789          * The log is on disk. It is now safe to update in place
 790          * in the primary metadata set.
 791          */
 792         ret = dmz_write_dirty_mblocks(zmd, &write_list, zmd->mblk_primary);
 793         if (ret)
 794                 goto err;
 795 
 796         ret = dmz_write_sb(zmd, zmd->mblk_primary);
 797         if (ret)
 798                 goto err;
 799 
 800         while (!list_empty(&write_list)) {
 801                 mblk = list_first_entry(&write_list, struct dmz_mblock, link);
 802                 list_del_init(&mblk->link);
 803 
 804                 spin_lock(&zmd->mblk_lock);
 805                 clear_bit(DMZ_META_DIRTY, &mblk->state);
 806                 if (mblk->ref == 0)
 807                         list_add_tail(&mblk->link, &zmd->mblk_lru_list);
 808                 spin_unlock(&zmd->mblk_lock);
 809         }
 810 
 811         zmd->sb_gen++;
 812 out:
 813         dmz_unlock_flush(zmd);
 814         up_write(&zmd->mblk_sem);
 815 
 816         return ret;
 817 
 818 err:
 819         if (!list_empty(&write_list)) {
 820                 spin_lock(&zmd->mblk_lock);
 821                 list_splice(&write_list, &zmd->mblk_dirty_list);
 822                 spin_unlock(&zmd->mblk_lock);
 823         }
 824         if (!dmz_check_bdev(zmd->dev))
 825                 ret = -EIO;
 826         goto out;
 827 }
 828 
 829 /*
 830  * Check super block.
 831  */
 832 static int dmz_check_sb(struct dmz_metadata *zmd, struct dmz_super *sb)
 833 {
 834         unsigned int nr_meta_zones, nr_data_zones;
 835         struct dmz_dev *dev = zmd->dev;
 836         u32 crc, stored_crc;
 837         u64 gen;
 838 
 839         gen = le64_to_cpu(sb->gen);
 840         stored_crc = le32_to_cpu(sb->crc);
 841         sb->crc = 0;
 842         crc = crc32_le(gen, (unsigned char *)sb, DMZ_BLOCK_SIZE);
 843         if (crc != stored_crc) {
 844                 dmz_dev_err(dev, "Invalid checksum (needed 0x%08x, got 0x%08x)",
 845                             crc, stored_crc);
 846                 return -ENXIO;
 847         }
 848 
 849         if (le32_to_cpu(sb->magic) != DMZ_MAGIC) {
 850                 dmz_dev_err(dev, "Invalid meta magic (needed 0x%08x, got 0x%08x)",
 851                             DMZ_MAGIC, le32_to_cpu(sb->magic));
 852                 return -ENXIO;
 853         }
 854 
 855         if (le32_to_cpu(sb->version) != DMZ_META_VER) {
 856                 dmz_dev_err(dev, "Invalid meta version (needed %d, got %d)",
 857                             DMZ_META_VER, le32_to_cpu(sb->version));
 858                 return -ENXIO;
 859         }
 860 
 861         nr_meta_zones = (le32_to_cpu(sb->nr_meta_blocks) + dev->zone_nr_blocks - 1)
 862                 >> dev->zone_nr_blocks_shift;
 863         if (!nr_meta_zones ||
 864             nr_meta_zones >= zmd->nr_rnd_zones) {
 865                 dmz_dev_err(dev, "Invalid number of metadata blocks");
 866                 return -ENXIO;
 867         }
 868 
 869         if (!le32_to_cpu(sb->nr_reserved_seq) ||
 870             le32_to_cpu(sb->nr_reserved_seq) >= (zmd->nr_useable_zones - nr_meta_zones)) {
 871                 dmz_dev_err(dev, "Invalid number of reserved sequential zones");
 872                 return -ENXIO;
 873         }
 874 
 875         nr_data_zones = zmd->nr_useable_zones -
 876                 (nr_meta_zones * 2 + le32_to_cpu(sb->nr_reserved_seq));
 877         if (le32_to_cpu(sb->nr_chunks) > nr_data_zones) {
 878                 dmz_dev_err(dev, "Invalid number of chunks %u / %u",
 879                             le32_to_cpu(sb->nr_chunks), nr_data_zones);
 880                 return -ENXIO;
 881         }
 882 
 883         /* OK */
 884         zmd->nr_meta_blocks = le32_to_cpu(sb->nr_meta_blocks);
 885         zmd->nr_reserved_seq = le32_to_cpu(sb->nr_reserved_seq);
 886         zmd->nr_chunks = le32_to_cpu(sb->nr_chunks);
 887         zmd->nr_map_blocks = le32_to_cpu(sb->nr_map_blocks);
 888         zmd->nr_bitmap_blocks = le32_to_cpu(sb->nr_bitmap_blocks);
 889         zmd->nr_meta_zones = nr_meta_zones;
 890         zmd->nr_data_zones = nr_data_zones;
 891 
 892         return 0;
 893 }
 894 
 895 /*
 896  * Read the first or second super block from disk.
 897  */
 898 static int dmz_read_sb(struct dmz_metadata *zmd, unsigned int set)
 899 {
 900         return dmz_rdwr_block(zmd, REQ_OP_READ, zmd->sb[set].block,
 901                               zmd->sb[set].mblk->page);
 902 }
 903 
 904 /*
 905  * Determine the position of the secondary super blocks on disk.
 906  * This is used only if a corruption of the primary super block
 907  * is detected.
 908  */
 909 static int dmz_lookup_secondary_sb(struct dmz_metadata *zmd)
 910 {
 911         unsigned int zone_nr_blocks = zmd->dev->zone_nr_blocks;
 912         struct dmz_mblock *mblk;
 913         int i;
 914 
 915         /* Allocate a block */
 916         mblk = dmz_alloc_mblock(zmd, 0);
 917         if (!mblk)
 918                 return -ENOMEM;
 919 
 920         zmd->sb[1].mblk = mblk;
 921         zmd->sb[1].sb = mblk->data;
 922 
 923         /* Bad first super block: search for the second one */
 924         zmd->sb[1].block = zmd->sb[0].block + zone_nr_blocks;
 925         for (i = 0; i < zmd->nr_rnd_zones - 1; i++) {
 926                 if (dmz_read_sb(zmd, 1) != 0)
 927                         break;
 928                 if (le32_to_cpu(zmd->sb[1].sb->magic) == DMZ_MAGIC)
 929                         return 0;
 930                 zmd->sb[1].block += zone_nr_blocks;
 931         }
 932 
 933         dmz_free_mblock(zmd, mblk);
 934         zmd->sb[1].mblk = NULL;
 935 
 936         return -EIO;
 937 }
 938 
 939 /*
 940  * Read the first or second super block from disk.
 941  */
 942 static int dmz_get_sb(struct dmz_metadata *zmd, unsigned int set)
 943 {
 944         struct dmz_mblock *mblk;
 945         int ret;
 946 
 947         /* Allocate a block */
 948         mblk = dmz_alloc_mblock(zmd, 0);
 949         if (!mblk)
 950                 return -ENOMEM;
 951 
 952         zmd->sb[set].mblk = mblk;
 953         zmd->sb[set].sb = mblk->data;
 954 
 955         /* Read super block */
 956         ret = dmz_read_sb(zmd, set);
 957         if (ret) {
 958                 dmz_free_mblock(zmd, mblk);
 959                 zmd->sb[set].mblk = NULL;
 960                 return ret;
 961         }
 962 
 963         return 0;
 964 }
 965 
 966 /*
 967  * Recover a metadata set.
 968  */
 969 static int dmz_recover_mblocks(struct dmz_metadata *zmd, unsigned int dst_set)
 970 {
 971         unsigned int src_set = dst_set ^ 0x1;
 972         struct page *page;
 973         int i, ret;
 974 
 975         dmz_dev_warn(zmd->dev, "Metadata set %u invalid: recovering", dst_set);
 976 
 977         if (dst_set == 0)
 978                 zmd->sb[0].block = dmz_start_block(zmd, zmd->sb_zone);
 979         else {
 980                 zmd->sb[1].block = zmd->sb[0].block +
 981                         (zmd->nr_meta_zones << zmd->dev->zone_nr_blocks_shift);
 982         }
 983 
 984         page = alloc_page(GFP_NOIO);
 985         if (!page)
 986                 return -ENOMEM;
 987 
 988         /* Copy metadata blocks */
 989         for (i = 1; i < zmd->nr_meta_blocks; i++) {
 990                 ret = dmz_rdwr_block(zmd, REQ_OP_READ,
 991                                      zmd->sb[src_set].block + i, page);
 992                 if (ret)
 993                         goto out;
 994                 ret = dmz_rdwr_block(zmd, REQ_OP_WRITE,
 995                                      zmd->sb[dst_set].block + i, page);
 996                 if (ret)
 997                         goto out;
 998         }
 999 
1000         /* Finalize with the super block */
1001         if (!zmd->sb[dst_set].mblk) {
1002                 zmd->sb[dst_set].mblk = dmz_alloc_mblock(zmd, 0);
1003                 if (!zmd->sb[dst_set].mblk) {
1004                         ret = -ENOMEM;
1005                         goto out;
1006                 }
1007                 zmd->sb[dst_set].sb = zmd->sb[dst_set].mblk->data;
1008         }
1009 
1010         ret = dmz_write_sb(zmd, dst_set);
1011 out:
1012         __free_pages(page, 0);
1013 
1014         return ret;
1015 }
1016 
1017 /*
1018  * Get super block from disk.
1019  */
1020 static int dmz_load_sb(struct dmz_metadata *zmd)
1021 {
1022         bool sb_good[2] = {false, false};
1023         u64 sb_gen[2] = {0, 0};
1024         int ret;
1025 
1026         /* Read and check the primary super block */
1027         zmd->sb[0].block = dmz_start_block(zmd, zmd->sb_zone);
1028         ret = dmz_get_sb(zmd, 0);
1029         if (ret) {
1030                 dmz_dev_err(zmd->dev, "Read primary super block failed");
1031                 return ret;
1032         }
1033 
1034         ret = dmz_check_sb(zmd, zmd->sb[0].sb);
1035 
1036         /* Read and check secondary super block */
1037         if (ret == 0) {
1038                 sb_good[0] = true;
1039                 zmd->sb[1].block = zmd->sb[0].block +
1040                         (zmd->nr_meta_zones << zmd->dev->zone_nr_blocks_shift);
1041                 ret = dmz_get_sb(zmd, 1);
1042         } else
1043                 ret = dmz_lookup_secondary_sb(zmd);
1044 
1045         if (ret) {
1046                 dmz_dev_err(zmd->dev, "Read secondary super block failed");
1047                 return ret;
1048         }
1049 
1050         ret = dmz_check_sb(zmd, zmd->sb[1].sb);
1051         if (ret == 0)
1052                 sb_good[1] = true;
1053 
1054         /* Use highest generation sb first */
1055         if (!sb_good[0] && !sb_good[1]) {
1056                 dmz_dev_err(zmd->dev, "No valid super block found");
1057                 return -EIO;
1058         }
1059 
1060         if (sb_good[0])
1061                 sb_gen[0] = le64_to_cpu(zmd->sb[0].sb->gen);
1062         else
1063                 ret = dmz_recover_mblocks(zmd, 0);
1064 
1065         if (sb_good[1])
1066                 sb_gen[1] = le64_to_cpu(zmd->sb[1].sb->gen);
1067         else
1068                 ret = dmz_recover_mblocks(zmd, 1);
1069 
1070         if (ret) {
1071                 dmz_dev_err(zmd->dev, "Recovery failed");
1072                 return -EIO;
1073         }
1074 
1075         if (sb_gen[0] >= sb_gen[1]) {
1076                 zmd->sb_gen = sb_gen[0];
1077                 zmd->mblk_primary = 0;
1078         } else {
1079                 zmd->sb_gen = sb_gen[1];
1080                 zmd->mblk_primary = 1;
1081         }
1082 
1083         dmz_dev_debug(zmd->dev, "Using super block %u (gen %llu)",
1084                       zmd->mblk_primary, zmd->sb_gen);
1085 
1086         return 0;
1087 }
1088 
1089 /*
1090  * Initialize a zone descriptor.
1091  */
1092 static int dmz_init_zone(struct dmz_metadata *zmd, struct dm_zone *zone,
1093                          struct blk_zone *blkz)
1094 {
1095         struct dmz_dev *dev = zmd->dev;
1096 
1097         /* Ignore the eventual last runt (smaller) zone */
1098         if (blkz->len != dev->zone_nr_sectors) {
1099                 if (blkz->start + blkz->len == dev->capacity)
1100                         return 0;
1101                 return -ENXIO;
1102         }
1103 
1104         INIT_LIST_HEAD(&zone->link);
1105         atomic_set(&zone->refcount, 0);
1106         zone->chunk = DMZ_MAP_UNMAPPED;
1107 
1108         if (blkz->type == BLK_ZONE_TYPE_CONVENTIONAL) {
1109                 set_bit(DMZ_RND, &zone->flags);
1110         } else if (blkz->type == BLK_ZONE_TYPE_SEQWRITE_REQ ||
1111                    blkz->type == BLK_ZONE_TYPE_SEQWRITE_PREF) {
1112                 set_bit(DMZ_SEQ, &zone->flags);
1113         } else
1114                 return -ENXIO;
1115 
1116         if (blkz->cond == BLK_ZONE_COND_OFFLINE)
1117                 set_bit(DMZ_OFFLINE, &zone->flags);
1118         else if (blkz->cond == BLK_ZONE_COND_READONLY)
1119                 set_bit(DMZ_READ_ONLY, &zone->flags);
1120 
1121         if (dmz_is_rnd(zone))
1122                 zone->wp_block = 0;
1123         else
1124                 zone->wp_block = dmz_sect2blk(blkz->wp - blkz->start);
1125 
1126         if (!dmz_is_offline(zone) && !dmz_is_readonly(zone)) {
1127                 zmd->nr_useable_zones++;
1128                 if (dmz_is_rnd(zone)) {
1129                         zmd->nr_rnd_zones++;
1130                         if (!zmd->sb_zone) {
1131                                 /* Super block zone */
1132                                 zmd->sb_zone = zone;
1133                         }
1134                 }
1135         }
1136 
1137         return 0;
1138 }
1139 
1140 /*
1141  * Free zones descriptors.
1142  */
1143 static void dmz_drop_zones(struct dmz_metadata *zmd)
1144 {
1145         kfree(zmd->zones);
1146         zmd->zones = NULL;
1147 }
1148 
1149 /*
1150  * The size of a zone report in number of zones.
1151  * This results in 4096*64B=256KB report zones commands.
1152  */
1153 #define DMZ_REPORT_NR_ZONES     4096
1154 
1155 /*
1156  * Allocate and initialize zone descriptors using the zone
1157  * information from disk.
1158  */
1159 static int dmz_init_zones(struct dmz_metadata *zmd)
1160 {
1161         struct dmz_dev *dev = zmd->dev;
1162         struct dm_zone *zone;
1163         struct blk_zone *blkz;
1164         unsigned int nr_blkz;
1165         sector_t sector = 0;
1166         int i, ret = 0;
1167 
1168         /* Init */
1169         zmd->zone_bitmap_size = dev->zone_nr_blocks >> 3;
1170         zmd->zone_nr_bitmap_blocks =
1171                 max_t(sector_t, 1, zmd->zone_bitmap_size >> DMZ_BLOCK_SHIFT);
1172         zmd->zone_bits_per_mblk = min_t(sector_t, dev->zone_nr_blocks,
1173                                         DMZ_BLOCK_SIZE_BITS);
1174 
1175         /* Allocate zone array */
1176         zmd->zones = kcalloc(dev->nr_zones, sizeof(struct dm_zone), GFP_KERNEL);
1177         if (!zmd->zones)
1178                 return -ENOMEM;
1179 
1180         dmz_dev_info(dev, "Using %zu B for zone information",
1181                      sizeof(struct dm_zone) * dev->nr_zones);
1182 
1183         /* Get zone information */
1184         nr_blkz = DMZ_REPORT_NR_ZONES;
1185         blkz = kcalloc(nr_blkz, sizeof(struct blk_zone), GFP_KERNEL);
1186         if (!blkz) {
1187                 ret = -ENOMEM;
1188                 goto out;
1189         }
1190 
1191         /*
1192          * Get zone information and initialize zone descriptors.
1193          * At the same time, determine where the super block
1194          * should be: first block of the first randomly writable
1195          * zone.
1196          */
1197         zone = zmd->zones;
1198         while (sector < dev->capacity) {
1199                 /* Get zone information */
1200                 nr_blkz = DMZ_REPORT_NR_ZONES;
1201                 ret = blkdev_report_zones(dev->bdev, sector, blkz, &nr_blkz);
1202                 if (ret) {
1203                         dmz_dev_err(dev, "Report zones failed %d", ret);
1204                         goto out;
1205                 }
1206 
1207                 if (!nr_blkz)
1208                         break;
1209 
1210                 /* Process report */
1211                 for (i = 0; i < nr_blkz; i++) {
1212                         ret = dmz_init_zone(zmd, zone, &blkz[i]);
1213                         if (ret)
1214                                 goto out;
1215                         sector += dev->zone_nr_sectors;
1216                         zone++;
1217                 }
1218         }
1219 
1220         /* The entire zone configuration of the disk should now be known */
1221         if (sector < dev->capacity) {
1222                 dmz_dev_err(dev, "Failed to get correct zone information");
1223                 ret = -ENXIO;
1224         }
1225 out:
1226         kfree(blkz);
1227         if (ret)
1228                 dmz_drop_zones(zmd);
1229 
1230         return ret;
1231 }
1232 
1233 /*
1234  * Update a zone information.
1235  */
1236 static int dmz_update_zone(struct dmz_metadata *zmd, struct dm_zone *zone)
1237 {
1238         unsigned int nr_blkz = 1;
1239         unsigned int noio_flag;
1240         struct blk_zone blkz;
1241         int ret;
1242 
1243         /*
1244          * Get zone information from disk. Since blkdev_report_zones() uses
1245          * GFP_KERNEL by default for memory allocations, set the per-task
1246          * PF_MEMALLOC_NOIO flag so that all allocations are done as if
1247          * GFP_NOIO was specified.
1248          */
1249         noio_flag = memalloc_noio_save();
1250         ret = blkdev_report_zones(zmd->dev->bdev, dmz_start_sect(zmd, zone),
1251                                   &blkz, &nr_blkz);
1252         memalloc_noio_restore(noio_flag);
1253         if (!nr_blkz)
1254                 ret = -EIO;
1255         if (ret) {
1256                 dmz_dev_err(zmd->dev, "Get zone %u report failed",
1257                             dmz_id(zmd, zone));
1258                 dmz_check_bdev(zmd->dev);
1259                 return ret;
1260         }
1261 
1262         clear_bit(DMZ_OFFLINE, &zone->flags);
1263         clear_bit(DMZ_READ_ONLY, &zone->flags);
1264         if (blkz.cond == BLK_ZONE_COND_OFFLINE)
1265                 set_bit(DMZ_OFFLINE, &zone->flags);
1266         else if (blkz.cond == BLK_ZONE_COND_READONLY)
1267                 set_bit(DMZ_READ_ONLY, &zone->flags);
1268 
1269         if (dmz_is_seq(zone))
1270                 zone->wp_block = dmz_sect2blk(blkz.wp - blkz.start);
1271         else
1272                 zone->wp_block = 0;
1273 
1274         return 0;
1275 }
1276 
1277 /*
1278  * Check a zone write pointer position when the zone is marked
1279  * with the sequential write error flag.
1280  */
1281 static int dmz_handle_seq_write_err(struct dmz_metadata *zmd,
1282                                     struct dm_zone *zone)
1283 {
1284         unsigned int wp = 0;
1285         int ret;
1286 
1287         wp = zone->wp_block;
1288         ret = dmz_update_zone(zmd, zone);
1289         if (ret)
1290                 return ret;
1291 
1292         dmz_dev_warn(zmd->dev, "Processing zone %u write error (zone wp %u/%u)",
1293                      dmz_id(zmd, zone), zone->wp_block, wp);
1294 
1295         if (zone->wp_block < wp) {
1296                 dmz_invalidate_blocks(zmd, zone, zone->wp_block,
1297                                       wp - zone->wp_block);
1298         }
1299 
1300         return 0;
1301 }
1302 
1303 static struct dm_zone *dmz_get(struct dmz_metadata *zmd, unsigned int zone_id)
1304 {
1305         return &zmd->zones[zone_id];
1306 }
1307 
1308 /*
1309  * Reset a zone write pointer.
1310  */
1311 static int dmz_reset_zone(struct dmz_metadata *zmd, struct dm_zone *zone)
1312 {
1313         int ret;
1314 
1315         /*
1316          * Ignore offline zones, read only zones,
1317          * and conventional zones.
1318          */
1319         if (dmz_is_offline(zone) ||
1320             dmz_is_readonly(zone) ||
1321             dmz_is_rnd(zone))
1322                 return 0;
1323 
1324         if (!dmz_is_empty(zone) || dmz_seq_write_err(zone)) {
1325                 struct dmz_dev *dev = zmd->dev;
1326 
1327                 ret = blkdev_reset_zones(dev->bdev,
1328                                          dmz_start_sect(zmd, zone),
1329                                          dev->zone_nr_sectors, GFP_NOIO);
1330                 if (ret) {
1331                         dmz_dev_err(dev, "Reset zone %u failed %d",
1332                                     dmz_id(zmd, zone), ret);
1333                         return ret;
1334                 }
1335         }
1336 
1337         /* Clear write error bit and rewind write pointer position */
1338         clear_bit(DMZ_SEQ_WRITE_ERR, &zone->flags);
1339         zone->wp_block = 0;
1340 
1341         return 0;
1342 }
1343 
1344 static void dmz_get_zone_weight(struct dmz_metadata *zmd, struct dm_zone *zone);
1345 
1346 /*
1347  * Initialize chunk mapping.
1348  */
1349 static int dmz_load_mapping(struct dmz_metadata *zmd)
1350 {
1351         struct dmz_dev *dev = zmd->dev;
1352         struct dm_zone *dzone, *bzone;
1353         struct dmz_mblock *dmap_mblk = NULL;
1354         struct dmz_map *dmap;
1355         unsigned int i = 0, e = 0, chunk = 0;
1356         unsigned int dzone_id;
1357         unsigned int bzone_id;
1358 
1359         /* Metadata block array for the chunk mapping table */
1360         zmd->map_mblk = kcalloc(zmd->nr_map_blocks,
1361                                 sizeof(struct dmz_mblk *), GFP_KERNEL);
1362         if (!zmd->map_mblk)
1363                 return -ENOMEM;
1364 
1365         /* Get chunk mapping table blocks and initialize zone mapping */
1366         while (chunk < zmd->nr_chunks) {
1367                 if (!dmap_mblk) {
1368                         /* Get mapping block */
1369                         dmap_mblk = dmz_get_mblock(zmd, i + 1);
1370                         if (IS_ERR(dmap_mblk))
1371                                 return PTR_ERR(dmap_mblk);
1372                         zmd->map_mblk[i] = dmap_mblk;
1373                         dmap = (struct dmz_map *) dmap_mblk->data;
1374                         i++;
1375                         e = 0;
1376                 }
1377 
1378                 /* Check data zone */
1379                 dzone_id = le32_to_cpu(dmap[e].dzone_id);
1380                 if (dzone_id == DMZ_MAP_UNMAPPED)
1381                         goto next;
1382 
1383                 if (dzone_id >= dev->nr_zones) {
1384                         dmz_dev_err(dev, "Chunk %u mapping: invalid data zone ID %u",
1385                                     chunk, dzone_id);
1386                         return -EIO;
1387                 }
1388 
1389                 dzone = dmz_get(zmd, dzone_id);
1390                 set_bit(DMZ_DATA, &dzone->flags);
1391                 dzone->chunk = chunk;
1392                 dmz_get_zone_weight(zmd, dzone);
1393 
1394                 if (dmz_is_rnd(dzone))
1395                         list_add_tail(&dzone->link, &zmd->map_rnd_list);
1396                 else
1397                         list_add_tail(&dzone->link, &zmd->map_seq_list);
1398 
1399                 /* Check buffer zone */
1400                 bzone_id = le32_to_cpu(dmap[e].bzone_id);
1401                 if (bzone_id == DMZ_MAP_UNMAPPED)
1402                         goto next;
1403 
1404                 if (bzone_id >= dev->nr_zones) {
1405                         dmz_dev_err(dev, "Chunk %u mapping: invalid buffer zone ID %u",
1406                                     chunk, bzone_id);
1407                         return -EIO;
1408                 }
1409 
1410                 bzone = dmz_get(zmd, bzone_id);
1411                 if (!dmz_is_rnd(bzone)) {
1412                         dmz_dev_err(dev, "Chunk %u mapping: invalid buffer zone %u",
1413                                     chunk, bzone_id);
1414                         return -EIO;
1415                 }
1416 
1417                 set_bit(DMZ_DATA, &bzone->flags);
1418                 set_bit(DMZ_BUF, &bzone->flags);
1419                 bzone->chunk = chunk;
1420                 bzone->bzone = dzone;
1421                 dzone->bzone = bzone;
1422                 dmz_get_zone_weight(zmd, bzone);
1423                 list_add_tail(&bzone->link, &zmd->map_rnd_list);
1424 next:
1425                 chunk++;
1426                 e++;
1427                 if (e >= DMZ_MAP_ENTRIES)
1428                         dmap_mblk = NULL;
1429         }
1430 
1431         /*
1432          * At this point, only meta zones and mapped data zones were
1433          * fully initialized. All remaining zones are unmapped data
1434          * zones. Finish initializing those here.
1435          */
1436         for (i = 0; i < dev->nr_zones; i++) {
1437                 dzone = dmz_get(zmd, i);
1438                 if (dmz_is_meta(dzone))
1439                         continue;
1440 
1441                 if (dmz_is_rnd(dzone))
1442                         zmd->nr_rnd++;
1443                 else
1444                         zmd->nr_seq++;
1445 
1446                 if (dmz_is_data(dzone)) {
1447                         /* Already initialized */
1448                         continue;
1449                 }
1450 
1451                 /* Unmapped data zone */
1452                 set_bit(DMZ_DATA, &dzone->flags);
1453                 dzone->chunk = DMZ_MAP_UNMAPPED;
1454                 if (dmz_is_rnd(dzone)) {
1455                         list_add_tail(&dzone->link, &zmd->unmap_rnd_list);
1456                         atomic_inc(&zmd->unmap_nr_rnd);
1457                 } else if (atomic_read(&zmd->nr_reserved_seq_zones) < zmd->nr_reserved_seq) {
1458                         list_add_tail(&dzone->link, &zmd->reserved_seq_zones_list);
1459                         atomic_inc(&zmd->nr_reserved_seq_zones);
1460                         zmd->nr_seq--;
1461                 } else {
1462                         list_add_tail(&dzone->link, &zmd->unmap_seq_list);
1463                         atomic_inc(&zmd->unmap_nr_seq);
1464                 }
1465         }
1466 
1467         return 0;
1468 }
1469 
1470 /*
1471  * Set a data chunk mapping.
1472  */
1473 static void dmz_set_chunk_mapping(struct dmz_metadata *zmd, unsigned int chunk,
1474                                   unsigned int dzone_id, unsigned int bzone_id)
1475 {
1476         struct dmz_mblock *dmap_mblk = zmd->map_mblk[chunk >> DMZ_MAP_ENTRIES_SHIFT];
1477         struct dmz_map *dmap = (struct dmz_map *) dmap_mblk->data;
1478         int map_idx = chunk & DMZ_MAP_ENTRIES_MASK;
1479 
1480         dmap[map_idx].dzone_id = cpu_to_le32(dzone_id);
1481         dmap[map_idx].bzone_id = cpu_to_le32(bzone_id);
1482         dmz_dirty_mblock(zmd, dmap_mblk);
1483 }
1484 
1485 /*
1486  * The list of mapped zones is maintained in LRU order.
1487  * This rotates a zone at the end of its map list.
1488  */
1489 static void __dmz_lru_zone(struct dmz_metadata *zmd, struct dm_zone *zone)
1490 {
1491         if (list_empty(&zone->link))
1492                 return;
1493 
1494         list_del_init(&zone->link);
1495         if (dmz_is_seq(zone)) {
1496                 /* LRU rotate sequential zone */
1497                 list_add_tail(&zone->link, &zmd->map_seq_list);
1498         } else {
1499                 /* LRU rotate random zone */
1500                 list_add_tail(&zone->link, &zmd->map_rnd_list);
1501         }
1502 }
1503 
1504 /*
1505  * The list of mapped random zones is maintained
1506  * in LRU order. This rotates a zone at the end of the list.
1507  */
1508 static void dmz_lru_zone(struct dmz_metadata *zmd, struct dm_zone *zone)
1509 {
1510         __dmz_lru_zone(zmd, zone);
1511         if (zone->bzone)
1512                 __dmz_lru_zone(zmd, zone->bzone);
1513 }
1514 
1515 /*
1516  * Wait for any zone to be freed.
1517  */
1518 static void dmz_wait_for_free_zones(struct dmz_metadata *zmd)
1519 {
1520         DEFINE_WAIT(wait);
1521 
1522         prepare_to_wait(&zmd->free_wq, &wait, TASK_UNINTERRUPTIBLE);
1523         dmz_unlock_map(zmd);
1524         dmz_unlock_metadata(zmd);
1525 
1526         io_schedule_timeout(HZ);
1527 
1528         dmz_lock_metadata(zmd);
1529         dmz_lock_map(zmd);
1530         finish_wait(&zmd->free_wq, &wait);
1531 }
1532 
1533 /*
1534  * Lock a zone for reclaim (set the zone RECLAIM bit).
1535  * Returns false if the zone cannot be locked or if it is already locked
1536  * and 1 otherwise.
1537  */
1538 int dmz_lock_zone_reclaim(struct dm_zone *zone)
1539 {
1540         /* Active zones cannot be reclaimed */
1541         if (dmz_is_active(zone))
1542                 return 0;
1543 
1544         return !test_and_set_bit(DMZ_RECLAIM, &zone->flags);
1545 }
1546 
1547 /*
1548  * Clear a zone reclaim flag.
1549  */
1550 void dmz_unlock_zone_reclaim(struct dm_zone *zone)
1551 {
1552         WARN_ON(dmz_is_active(zone));
1553         WARN_ON(!dmz_in_reclaim(zone));
1554 
1555         clear_bit_unlock(DMZ_RECLAIM, &zone->flags);
1556         smp_mb__after_atomic();
1557         wake_up_bit(&zone->flags, DMZ_RECLAIM);
1558 }
1559 
1560 /*
1561  * Wait for a zone reclaim to complete.
1562  */
1563 static void dmz_wait_for_reclaim(struct dmz_metadata *zmd, struct dm_zone *zone)
1564 {
1565         dmz_unlock_map(zmd);
1566         dmz_unlock_metadata(zmd);
1567         wait_on_bit_timeout(&zone->flags, DMZ_RECLAIM, TASK_UNINTERRUPTIBLE, HZ);
1568         dmz_lock_metadata(zmd);
1569         dmz_lock_map(zmd);
1570 }
1571 
1572 /*
1573  * Select a random write zone for reclaim.
1574  */
1575 static struct dm_zone *dmz_get_rnd_zone_for_reclaim(struct dmz_metadata *zmd)
1576 {
1577         struct dm_zone *dzone = NULL;
1578         struct dm_zone *zone;
1579 
1580         if (list_empty(&zmd->map_rnd_list))
1581                 return ERR_PTR(-EBUSY);
1582 
1583         list_for_each_entry(zone, &zmd->map_rnd_list, link) {
1584                 if (dmz_is_buf(zone))
1585                         dzone = zone->bzone;
1586                 else
1587                         dzone = zone;
1588                 if (dmz_lock_zone_reclaim(dzone))
1589                         return dzone;
1590         }
1591 
1592         return ERR_PTR(-EBUSY);
1593 }
1594 
1595 /*
1596  * Select a buffered sequential zone for reclaim.
1597  */
1598 static struct dm_zone *dmz_get_seq_zone_for_reclaim(struct dmz_metadata *zmd)
1599 {
1600         struct dm_zone *zone;
1601 
1602         if (list_empty(&zmd->map_seq_list))
1603                 return ERR_PTR(-EBUSY);
1604 
1605         list_for_each_entry(zone, &zmd->map_seq_list, link) {
1606                 if (!zone->bzone)
1607                         continue;
1608                 if (dmz_lock_zone_reclaim(zone))
1609                         return zone;
1610         }
1611 
1612         return ERR_PTR(-EBUSY);
1613 }
1614 
1615 /*
1616  * Select a zone for reclaim.
1617  */
1618 struct dm_zone *dmz_get_zone_for_reclaim(struct dmz_metadata *zmd)
1619 {
1620         struct dm_zone *zone;
1621 
1622         /*
1623          * Search for a zone candidate to reclaim: 2 cases are possible.
1624          * (1) There is no free sequential zones. Then a random data zone
1625          *     cannot be reclaimed. So choose a sequential zone to reclaim so
1626          *     that afterward a random zone can be reclaimed.
1627          * (2) At least one free sequential zone is available, then choose
1628          *     the oldest random zone (data or buffer) that can be locked.
1629          */
1630         dmz_lock_map(zmd);
1631         if (list_empty(&zmd->reserved_seq_zones_list))
1632                 zone = dmz_get_seq_zone_for_reclaim(zmd);
1633         else
1634                 zone = dmz_get_rnd_zone_for_reclaim(zmd);
1635         dmz_unlock_map(zmd);
1636 
1637         return zone;
1638 }
1639 
1640 /*
1641  * Get the zone mapping a chunk, if the chunk is mapped already.
1642  * If no mapping exist and the operation is WRITE, a zone is
1643  * allocated and used to map the chunk.
1644  * The zone returned will be set to the active state.
1645  */
1646 struct dm_zone *dmz_get_chunk_mapping(struct dmz_metadata *zmd, unsigned int chunk, int op)
1647 {
1648         struct dmz_mblock *dmap_mblk = zmd->map_mblk[chunk >> DMZ_MAP_ENTRIES_SHIFT];
1649         struct dmz_map *dmap = (struct dmz_map *) dmap_mblk->data;
1650         int dmap_idx = chunk & DMZ_MAP_ENTRIES_MASK;
1651         unsigned int dzone_id;
1652         struct dm_zone *dzone = NULL;
1653         int ret = 0;
1654 
1655         dmz_lock_map(zmd);
1656 again:
1657         /* Get the chunk mapping */
1658         dzone_id = le32_to_cpu(dmap[dmap_idx].dzone_id);
1659         if (dzone_id == DMZ_MAP_UNMAPPED) {
1660                 /*
1661                  * Read or discard in unmapped chunks are fine. But for
1662                  * writes, we need a mapping, so get one.
1663                  */
1664                 if (op != REQ_OP_WRITE)
1665                         goto out;
1666 
1667                 /* Allocate a random zone */
1668                 dzone = dmz_alloc_zone(zmd, DMZ_ALLOC_RND);
1669                 if (!dzone) {
1670                         if (dmz_bdev_is_dying(zmd->dev)) {
1671                                 dzone = ERR_PTR(-EIO);
1672                                 goto out;
1673                         }
1674                         dmz_wait_for_free_zones(zmd);
1675                         goto again;
1676                 }
1677 
1678                 dmz_map_zone(zmd, dzone, chunk);
1679 
1680         } else {
1681                 /* The chunk is already mapped: get the mapping zone */
1682                 dzone = dmz_get(zmd, dzone_id);
1683                 if (dzone->chunk != chunk) {
1684                         dzone = ERR_PTR(-EIO);
1685                         goto out;
1686                 }
1687 
1688                 /* Repair write pointer if the sequential dzone has error */
1689                 if (dmz_seq_write_err(dzone)) {
1690                         ret = dmz_handle_seq_write_err(zmd, dzone);
1691                         if (ret) {
1692                                 dzone = ERR_PTR(-EIO);
1693                                 goto out;
1694                         }
1695                         clear_bit(DMZ_SEQ_WRITE_ERR, &dzone->flags);
1696                 }
1697         }
1698 
1699         /*
1700          * If the zone is being reclaimed, the chunk mapping may change
1701          * to a different zone. So wait for reclaim and retry. Otherwise,
1702          * activate the zone (this will prevent reclaim from touching it).
1703          */
1704         if (dmz_in_reclaim(dzone)) {
1705                 dmz_wait_for_reclaim(zmd, dzone);
1706                 goto again;
1707         }
1708         dmz_activate_zone(dzone);
1709         dmz_lru_zone(zmd, dzone);
1710 out:
1711         dmz_unlock_map(zmd);
1712 
1713         return dzone;
1714 }
1715 
1716 /*
1717  * Write and discard change the block validity of data zones and their buffer
1718  * zones. Check here that valid blocks are still present. If all blocks are
1719  * invalid, the zones can be unmapped on the fly without waiting for reclaim
1720  * to do it.
1721  */
1722 void dmz_put_chunk_mapping(struct dmz_metadata *zmd, struct dm_zone *dzone)
1723 {
1724         struct dm_zone *bzone;
1725 
1726         dmz_lock_map(zmd);
1727 
1728         bzone = dzone->bzone;
1729         if (bzone) {
1730                 if (dmz_weight(bzone))
1731                         dmz_lru_zone(zmd, bzone);
1732                 else {
1733                         /* Empty buffer zone: reclaim it */
1734                         dmz_unmap_zone(zmd, bzone);
1735                         dmz_free_zone(zmd, bzone);
1736                         bzone = NULL;
1737                 }
1738         }
1739 
1740         /* Deactivate the data zone */
1741         dmz_deactivate_zone(dzone);
1742         if (dmz_is_active(dzone) || bzone || dmz_weight(dzone))
1743                 dmz_lru_zone(zmd, dzone);
1744         else {
1745                 /* Unbuffered inactive empty data zone: reclaim it */
1746                 dmz_unmap_zone(zmd, dzone);
1747                 dmz_free_zone(zmd, dzone);
1748         }
1749 
1750         dmz_unlock_map(zmd);
1751 }
1752 
1753 /*
1754  * Allocate and map a random zone to buffer a chunk
1755  * already mapped to a sequential zone.
1756  */
1757 struct dm_zone *dmz_get_chunk_buffer(struct dmz_metadata *zmd,
1758                                      struct dm_zone *dzone)
1759 {
1760         struct dm_zone *bzone;
1761 
1762         dmz_lock_map(zmd);
1763 again:
1764         bzone = dzone->bzone;
1765         if (bzone)
1766                 goto out;
1767 
1768         /* Allocate a random zone */
1769         bzone = dmz_alloc_zone(zmd, DMZ_ALLOC_RND);
1770         if (!bzone) {
1771                 if (dmz_bdev_is_dying(zmd->dev)) {
1772                         bzone = ERR_PTR(-EIO);
1773                         goto out;
1774                 }
1775                 dmz_wait_for_free_zones(zmd);
1776                 goto again;
1777         }
1778 
1779         /* Update the chunk mapping */
1780         dmz_set_chunk_mapping(zmd, dzone->chunk, dmz_id(zmd, dzone),
1781                               dmz_id(zmd, bzone));
1782 
1783         set_bit(DMZ_BUF, &bzone->flags);
1784         bzone->chunk = dzone->chunk;
1785         bzone->bzone = dzone;
1786         dzone->bzone = bzone;
1787         list_add_tail(&bzone->link, &zmd->map_rnd_list);
1788 out:
1789         dmz_unlock_map(zmd);
1790 
1791         return bzone;
1792 }
1793 
1794 /*
1795  * Get an unmapped (free) zone.
1796  * This must be called with the mapping lock held.
1797  */
1798 struct dm_zone *dmz_alloc_zone(struct dmz_metadata *zmd, unsigned long flags)
1799 {
1800         struct list_head *list;
1801         struct dm_zone *zone;
1802 
1803         if (flags & DMZ_ALLOC_RND)
1804                 list = &zmd->unmap_rnd_list;
1805         else
1806                 list = &zmd->unmap_seq_list;
1807 again:
1808         if (list_empty(list)) {
1809                 /*
1810                  * No free zone: if this is for reclaim, allow using the
1811                  * reserved sequential zones.
1812                  */
1813                 if (!(flags & DMZ_ALLOC_RECLAIM) ||
1814                     list_empty(&zmd->reserved_seq_zones_list))
1815                         return NULL;
1816 
1817                 zone = list_first_entry(&zmd->reserved_seq_zones_list,
1818                                         struct dm_zone, link);
1819                 list_del_init(&zone->link);
1820                 atomic_dec(&zmd->nr_reserved_seq_zones);
1821                 return zone;
1822         }
1823 
1824         zone = list_first_entry(list, struct dm_zone, link);
1825         list_del_init(&zone->link);
1826 
1827         if (dmz_is_rnd(zone))
1828                 atomic_dec(&zmd->unmap_nr_rnd);
1829         else
1830                 atomic_dec(&zmd->unmap_nr_seq);
1831 
1832         if (dmz_is_offline(zone)) {
1833                 dmz_dev_warn(zmd->dev, "Zone %u is offline", dmz_id(zmd, zone));
1834                 zone = NULL;
1835                 goto again;
1836         }
1837 
1838         return zone;
1839 }
1840 
1841 /*
1842  * Free a zone.
1843  * This must be called with the mapping lock held.
1844  */
1845 void dmz_free_zone(struct dmz_metadata *zmd, struct dm_zone *zone)
1846 {
1847         /* If this is a sequential zone, reset it */
1848         if (dmz_is_seq(zone))
1849                 dmz_reset_zone(zmd, zone);
1850 
1851         /* Return the zone to its type unmap list */
1852         if (dmz_is_rnd(zone)) {
1853                 list_add_tail(&zone->link, &zmd->unmap_rnd_list);
1854                 atomic_inc(&zmd->unmap_nr_rnd);
1855         } else if (atomic_read(&zmd->nr_reserved_seq_zones) <
1856                    zmd->nr_reserved_seq) {
1857                 list_add_tail(&zone->link, &zmd->reserved_seq_zones_list);
1858                 atomic_inc(&zmd->nr_reserved_seq_zones);
1859         } else {
1860                 list_add_tail(&zone->link, &zmd->unmap_seq_list);
1861                 atomic_inc(&zmd->unmap_nr_seq);
1862         }
1863 
1864         wake_up_all(&zmd->free_wq);
1865 }
1866 
1867 /*
1868  * Map a chunk to a zone.
1869  * This must be called with the mapping lock held.
1870  */
1871 void dmz_map_zone(struct dmz_metadata *zmd, struct dm_zone *dzone,
1872                   unsigned int chunk)
1873 {
1874         /* Set the chunk mapping */
1875         dmz_set_chunk_mapping(zmd, chunk, dmz_id(zmd, dzone),
1876                               DMZ_MAP_UNMAPPED);
1877         dzone->chunk = chunk;
1878         if (dmz_is_rnd(dzone))
1879                 list_add_tail(&dzone->link, &zmd->map_rnd_list);
1880         else
1881                 list_add_tail(&dzone->link, &zmd->map_seq_list);
1882 }
1883 
1884 /*
1885  * Unmap a zone.
1886  * This must be called with the mapping lock held.
1887  */
1888 void dmz_unmap_zone(struct dmz_metadata *zmd, struct dm_zone *zone)
1889 {
1890         unsigned int chunk = zone->chunk;
1891         unsigned int dzone_id;
1892 
1893         if (chunk == DMZ_MAP_UNMAPPED) {
1894                 /* Already unmapped */
1895                 return;
1896         }
1897 
1898         if (test_and_clear_bit(DMZ_BUF, &zone->flags)) {
1899                 /*
1900                  * Unmapping the chunk buffer zone: clear only
1901                  * the chunk buffer mapping
1902                  */
1903                 dzone_id = dmz_id(zmd, zone->bzone);
1904                 zone->bzone->bzone = NULL;
1905                 zone->bzone = NULL;
1906 
1907         } else {
1908                 /*
1909                  * Unmapping the chunk data zone: the zone must
1910                  * not be buffered.
1911                  */
1912                 if (WARN_ON(zone->bzone)) {
1913                         zone->bzone->bzone = NULL;
1914                         zone->bzone = NULL;
1915                 }
1916                 dzone_id = DMZ_MAP_UNMAPPED;
1917         }
1918 
1919         dmz_set_chunk_mapping(zmd, chunk, dzone_id, DMZ_MAP_UNMAPPED);
1920 
1921         zone->chunk = DMZ_MAP_UNMAPPED;
1922         list_del_init(&zone->link);
1923 }
1924 
1925 /*
1926  * Set @nr_bits bits in @bitmap starting from @bit.
1927  * Return the number of bits changed from 0 to 1.
1928  */
1929 static unsigned int dmz_set_bits(unsigned long *bitmap,
1930                                  unsigned int bit, unsigned int nr_bits)
1931 {
1932         unsigned long *addr;
1933         unsigned int end = bit + nr_bits;
1934         unsigned int n = 0;
1935 
1936         while (bit < end) {
1937                 if (((bit & (BITS_PER_LONG - 1)) == 0) &&
1938                     ((end - bit) >= BITS_PER_LONG)) {
1939                         /* Try to set the whole word at once */
1940                         addr = bitmap + BIT_WORD(bit);
1941                         if (*addr == 0) {
1942                                 *addr = ULONG_MAX;
1943                                 n += BITS_PER_LONG;
1944                                 bit += BITS_PER_LONG;
1945                                 continue;
1946                         }
1947                 }
1948 
1949                 if (!test_and_set_bit(bit, bitmap))
1950                         n++;
1951                 bit++;
1952         }
1953 
1954         return n;
1955 }
1956 
1957 /*
1958  * Get the bitmap block storing the bit for chunk_block in zone.
1959  */
1960 static struct dmz_mblock *dmz_get_bitmap(struct dmz_metadata *zmd,
1961                                          struct dm_zone *zone,
1962                                          sector_t chunk_block)
1963 {
1964         sector_t bitmap_block = 1 + zmd->nr_map_blocks +
1965                 (sector_t)(dmz_id(zmd, zone) * zmd->zone_nr_bitmap_blocks) +
1966                 (chunk_block >> DMZ_BLOCK_SHIFT_BITS);
1967 
1968         return dmz_get_mblock(zmd, bitmap_block);
1969 }
1970 
1971 /*
1972  * Copy the valid blocks bitmap of from_zone to the bitmap of to_zone.
1973  */
1974 int dmz_copy_valid_blocks(struct dmz_metadata *zmd, struct dm_zone *from_zone,
1975                           struct dm_zone *to_zone)
1976 {
1977         struct dmz_mblock *from_mblk, *to_mblk;
1978         sector_t chunk_block = 0;
1979 
1980         /* Get the zones bitmap blocks */
1981         while (chunk_block < zmd->dev->zone_nr_blocks) {
1982                 from_mblk = dmz_get_bitmap(zmd, from_zone, chunk_block);
1983                 if (IS_ERR(from_mblk))
1984                         return PTR_ERR(from_mblk);
1985                 to_mblk = dmz_get_bitmap(zmd, to_zone, chunk_block);
1986                 if (IS_ERR(to_mblk)) {
1987                         dmz_release_mblock(zmd, from_mblk);
1988                         return PTR_ERR(to_mblk);
1989                 }
1990 
1991                 memcpy(to_mblk->data, from_mblk->data, DMZ_BLOCK_SIZE);
1992                 dmz_dirty_mblock(zmd, to_mblk);
1993 
1994                 dmz_release_mblock(zmd, to_mblk);
1995                 dmz_release_mblock(zmd, from_mblk);
1996 
1997                 chunk_block += zmd->zone_bits_per_mblk;
1998         }
1999 
2000         to_zone->weight = from_zone->weight;
2001 
2002         return 0;
2003 }
2004 
2005 /*
2006  * Merge the valid blocks bitmap of from_zone into the bitmap of to_zone,
2007  * starting from chunk_block.
2008  */
2009 int dmz_merge_valid_blocks(struct dmz_metadata *zmd, struct dm_zone *from_zone,
2010                            struct dm_zone *to_zone, sector_t chunk_block)
2011 {
2012         unsigned int nr_blocks;
2013         int ret;
2014 
2015         /* Get the zones bitmap blocks */
2016         while (chunk_block < zmd->dev->zone_nr_blocks) {
2017                 /* Get a valid region from the source zone */
2018                 ret = dmz_first_valid_block(zmd, from_zone, &chunk_block);
2019                 if (ret <= 0)
2020                         return ret;
2021 
2022                 nr_blocks = ret;
2023                 ret = dmz_validate_blocks(zmd, to_zone, chunk_block, nr_blocks);
2024                 if (ret)
2025                         return ret;
2026 
2027                 chunk_block += nr_blocks;
2028         }
2029 
2030         return 0;
2031 }
2032 
2033 /*
2034  * Validate all the blocks in the range [block..block+nr_blocks-1].
2035  */
2036 int dmz_validate_blocks(struct dmz_metadata *zmd, struct dm_zone *zone,
2037                         sector_t chunk_block, unsigned int nr_blocks)
2038 {
2039         unsigned int count, bit, nr_bits;
2040         unsigned int zone_nr_blocks = zmd->dev->zone_nr_blocks;
2041         struct dmz_mblock *mblk;
2042         unsigned int n = 0;
2043 
2044         dmz_dev_debug(zmd->dev, "=> VALIDATE zone %u, block %llu, %u blocks",
2045                       dmz_id(zmd, zone), (unsigned long long)chunk_block,
2046                       nr_blocks);
2047 
2048         WARN_ON(chunk_block + nr_blocks > zone_nr_blocks);
2049 
2050         while (nr_blocks) {
2051                 /* Get bitmap block */
2052                 mblk = dmz_get_bitmap(zmd, zone, chunk_block);
2053                 if (IS_ERR(mblk))
2054                         return PTR_ERR(mblk);
2055 
2056                 /* Set bits */
2057                 bit = chunk_block & DMZ_BLOCK_MASK_BITS;
2058                 nr_bits = min(nr_blocks, zmd->zone_bits_per_mblk - bit);
2059 
2060                 count = dmz_set_bits((unsigned long *)mblk->data, bit, nr_bits);
2061                 if (count) {
2062                         dmz_dirty_mblock(zmd, mblk);
2063                         n += count;
2064                 }
2065                 dmz_release_mblock(zmd, mblk);
2066 
2067                 nr_blocks -= nr_bits;
2068                 chunk_block += nr_bits;
2069         }
2070 
2071         if (likely(zone->weight + n <= zone_nr_blocks))
2072                 zone->weight += n;
2073         else {
2074                 dmz_dev_warn(zmd->dev, "Zone %u: weight %u should be <= %u",
2075                              dmz_id(zmd, zone), zone->weight,
2076                              zone_nr_blocks - n);
2077                 zone->weight = zone_nr_blocks;
2078         }
2079 
2080         return 0;
2081 }
2082 
2083 /*
2084  * Clear nr_bits bits in bitmap starting from bit.
2085  * Return the number of bits cleared.
2086  */
2087 static int dmz_clear_bits(unsigned long *bitmap, int bit, int nr_bits)
2088 {
2089         unsigned long *addr;
2090         int end = bit + nr_bits;
2091         int n = 0;
2092 
2093         while (bit < end) {
2094                 if (((bit & (BITS_PER_LONG - 1)) == 0) &&
2095                     ((end - bit) >= BITS_PER_LONG)) {
2096                         /* Try to clear whole word at once */
2097                         addr = bitmap + BIT_WORD(bit);
2098                         if (*addr == ULONG_MAX) {
2099                                 *addr = 0;
2100                                 n += BITS_PER_LONG;
2101                                 bit += BITS_PER_LONG;
2102                                 continue;
2103                         }
2104                 }
2105 
2106                 if (test_and_clear_bit(bit, bitmap))
2107                         n++;
2108                 bit++;
2109         }
2110 
2111         return n;
2112 }
2113 
2114 /*
2115  * Invalidate all the blocks in the range [block..block+nr_blocks-1].
2116  */
2117 int dmz_invalidate_blocks(struct dmz_metadata *zmd, struct dm_zone *zone,
2118                           sector_t chunk_block, unsigned int nr_blocks)
2119 {
2120         unsigned int count, bit, nr_bits;
2121         struct dmz_mblock *mblk;
2122         unsigned int n = 0;
2123 
2124         dmz_dev_debug(zmd->dev, "=> INVALIDATE zone %u, block %llu, %u blocks",
2125                       dmz_id(zmd, zone), (u64)chunk_block, nr_blocks);
2126 
2127         WARN_ON(chunk_block + nr_blocks > zmd->dev->zone_nr_blocks);
2128 
2129         while (nr_blocks) {
2130                 /* Get bitmap block */
2131                 mblk = dmz_get_bitmap(zmd, zone, chunk_block);
2132                 if (IS_ERR(mblk))
2133                         return PTR_ERR(mblk);
2134 
2135                 /* Clear bits */
2136                 bit = chunk_block & DMZ_BLOCK_MASK_BITS;
2137                 nr_bits = min(nr_blocks, zmd->zone_bits_per_mblk - bit);
2138 
2139                 count = dmz_clear_bits((unsigned long *)mblk->data,
2140                                        bit, nr_bits);
2141                 if (count) {
2142                         dmz_dirty_mblock(zmd, mblk);
2143                         n += count;
2144                 }
2145                 dmz_release_mblock(zmd, mblk);
2146 
2147                 nr_blocks -= nr_bits;
2148                 chunk_block += nr_bits;
2149         }
2150 
2151         if (zone->weight >= n)
2152                 zone->weight -= n;
2153         else {
2154                 dmz_dev_warn(zmd->dev, "Zone %u: weight %u should be >= %u",
2155                              dmz_id(zmd, zone), zone->weight, n);
2156                 zone->weight = 0;
2157         }
2158 
2159         return 0;
2160 }
2161 
2162 /*
2163  * Get a block bit value.
2164  */
2165 static int dmz_test_block(struct dmz_metadata *zmd, struct dm_zone *zone,
2166                           sector_t chunk_block)
2167 {
2168         struct dmz_mblock *mblk;
2169         int ret;
2170 
2171         WARN_ON(chunk_block >= zmd->dev->zone_nr_blocks);
2172 
2173         /* Get bitmap block */
2174         mblk = dmz_get_bitmap(zmd, zone, chunk_block);
2175         if (IS_ERR(mblk))
2176                 return PTR_ERR(mblk);
2177 
2178         /* Get offset */
2179         ret = test_bit(chunk_block & DMZ_BLOCK_MASK_BITS,
2180                        (unsigned long *) mblk->data) != 0;
2181 
2182         dmz_release_mblock(zmd, mblk);
2183 
2184         return ret;
2185 }
2186 
2187 /*
2188  * Return the number of blocks from chunk_block to the first block with a bit
2189  * value specified by set. Search at most nr_blocks blocks from chunk_block.
2190  */
2191 static int dmz_to_next_set_block(struct dmz_metadata *zmd, struct dm_zone *zone,
2192                                  sector_t chunk_block, unsigned int nr_blocks,
2193                                  int set)
2194 {
2195         struct dmz_mblock *mblk;
2196         unsigned int bit, set_bit, nr_bits;
2197         unsigned int zone_bits = zmd->zone_bits_per_mblk;
2198         unsigned long *bitmap;
2199         int n = 0;
2200 
2201         WARN_ON(chunk_block + nr_blocks > zmd->dev->zone_nr_blocks);
2202 
2203         while (nr_blocks) {
2204                 /* Get bitmap block */
2205                 mblk = dmz_get_bitmap(zmd, zone, chunk_block);
2206                 if (IS_ERR(mblk))
2207                         return PTR_ERR(mblk);
2208 
2209                 /* Get offset */
2210                 bitmap = (unsigned long *) mblk->data;
2211                 bit = chunk_block & DMZ_BLOCK_MASK_BITS;
2212                 nr_bits = min(nr_blocks, zone_bits - bit);
2213                 if (set)
2214                         set_bit = find_next_bit(bitmap, zone_bits, bit);
2215                 else
2216                         set_bit = find_next_zero_bit(bitmap, zone_bits, bit);
2217                 dmz_release_mblock(zmd, mblk);
2218 
2219                 n += set_bit - bit;
2220                 if (set_bit < zone_bits)
2221                         break;
2222 
2223                 nr_blocks -= nr_bits;
2224                 chunk_block += nr_bits;
2225         }
2226 
2227         return n;
2228 }
2229 
2230 /*
2231  * Test if chunk_block is valid. If it is, the number of consecutive
2232  * valid blocks from chunk_block will be returned.
2233  */
2234 int dmz_block_valid(struct dmz_metadata *zmd, struct dm_zone *zone,
2235                     sector_t chunk_block)
2236 {
2237         int valid;
2238 
2239         valid = dmz_test_block(zmd, zone, chunk_block);
2240         if (valid <= 0)
2241                 return valid;
2242 
2243         /* The block is valid: get the number of valid blocks from block */
2244         return dmz_to_next_set_block(zmd, zone, chunk_block,
2245                                      zmd->dev->zone_nr_blocks - chunk_block, 0);
2246 }
2247 
2248 /*
2249  * Find the first valid block from @chunk_block in @zone.
2250  * If such a block is found, its number is returned using
2251  * @chunk_block and the total number of valid blocks from @chunk_block
2252  * is returned.
2253  */
2254 int dmz_first_valid_block(struct dmz_metadata *zmd, struct dm_zone *zone,
2255                           sector_t *chunk_block)
2256 {
2257         sector_t start_block = *chunk_block;
2258         int ret;
2259 
2260         ret = dmz_to_next_set_block(zmd, zone, start_block,
2261                                     zmd->dev->zone_nr_blocks - start_block, 1);
2262         if (ret < 0)
2263                 return ret;
2264 
2265         start_block += ret;
2266         *chunk_block = start_block;
2267 
2268         return dmz_to_next_set_block(zmd, zone, start_block,
2269                                      zmd->dev->zone_nr_blocks - start_block, 0);
2270 }
2271 
2272 /*
2273  * Count the number of bits set starting from bit up to bit + nr_bits - 1.
2274  */
2275 static int dmz_count_bits(void *bitmap, int bit, int nr_bits)
2276 {
2277         unsigned long *addr;
2278         int end = bit + nr_bits;
2279         int n = 0;
2280 
2281         while (bit < end) {
2282                 if (((bit & (BITS_PER_LONG - 1)) == 0) &&
2283                     ((end - bit) >= BITS_PER_LONG)) {
2284                         addr = (unsigned long *)bitmap + BIT_WORD(bit);
2285                         if (*addr == ULONG_MAX) {
2286                                 n += BITS_PER_LONG;
2287                                 bit += BITS_PER_LONG;
2288                                 continue;
2289                         }
2290                 }
2291 
2292                 if (test_bit(bit, bitmap))
2293                         n++;
2294                 bit++;
2295         }
2296 
2297         return n;
2298 }
2299 
2300 /*
2301  * Get a zone weight.
2302  */
2303 static void dmz_get_zone_weight(struct dmz_metadata *zmd, struct dm_zone *zone)
2304 {
2305         struct dmz_mblock *mblk;
2306         sector_t chunk_block = 0;
2307         unsigned int bit, nr_bits;
2308         unsigned int nr_blocks = zmd->dev->zone_nr_blocks;
2309         void *bitmap;
2310         int n = 0;
2311 
2312         while (nr_blocks) {
2313                 /* Get bitmap block */
2314                 mblk = dmz_get_bitmap(zmd, zone, chunk_block);
2315                 if (IS_ERR(mblk)) {
2316                         n = 0;
2317                         break;
2318                 }
2319 
2320                 /* Count bits in this block */
2321                 bitmap = mblk->data;
2322                 bit = chunk_block & DMZ_BLOCK_MASK_BITS;
2323                 nr_bits = min(nr_blocks, zmd->zone_bits_per_mblk - bit);
2324                 n += dmz_count_bits(bitmap, bit, nr_bits);
2325 
2326                 dmz_release_mblock(zmd, mblk);
2327 
2328                 nr_blocks -= nr_bits;
2329                 chunk_block += nr_bits;
2330         }
2331 
2332         zone->weight = n;
2333 }
2334 
2335 /*
2336  * Cleanup the zoned metadata resources.
2337  */
2338 static void dmz_cleanup_metadata(struct dmz_metadata *zmd)
2339 {
2340         struct rb_root *root;
2341         struct dmz_mblock *mblk, *next;
2342         int i;
2343 
2344         /* Release zone mapping resources */
2345         if (zmd->map_mblk) {
2346                 for (i = 0; i < zmd->nr_map_blocks; i++)
2347                         dmz_release_mblock(zmd, zmd->map_mblk[i]);
2348                 kfree(zmd->map_mblk);
2349                 zmd->map_mblk = NULL;
2350         }
2351 
2352         /* Release super blocks */
2353         for (i = 0; i < 2; i++) {
2354                 if (zmd->sb[i].mblk) {
2355                         dmz_free_mblock(zmd, zmd->sb[i].mblk);
2356                         zmd->sb[i].mblk = NULL;
2357                 }
2358         }
2359 
2360         /* Free cached blocks */
2361         while (!list_empty(&zmd->mblk_dirty_list)) {
2362                 mblk = list_first_entry(&zmd->mblk_dirty_list,
2363                                         struct dmz_mblock, link);
2364                 dmz_dev_warn(zmd->dev, "mblock %llu still in dirty list (ref %u)",
2365                              (u64)mblk->no, mblk->ref);
2366                 list_del_init(&mblk->link);
2367                 rb_erase(&mblk->node, &zmd->mblk_rbtree);
2368                 dmz_free_mblock(zmd, mblk);
2369         }
2370 
2371         while (!list_empty(&zmd->mblk_lru_list)) {
2372                 mblk = list_first_entry(&zmd->mblk_lru_list,
2373                                         struct dmz_mblock, link);
2374                 list_del_init(&mblk->link);
2375                 rb_erase(&mblk->node, &zmd->mblk_rbtree);
2376                 dmz_free_mblock(zmd, mblk);
2377         }
2378 
2379         /* Sanity checks: the mblock rbtree should now be empty */
2380         root = &zmd->mblk_rbtree;
2381         rbtree_postorder_for_each_entry_safe(mblk, next, root, node) {
2382                 dmz_dev_warn(zmd->dev, "mblock %llu ref %u still in rbtree",
2383                              (u64)mblk->no, mblk->ref);
2384                 mblk->ref = 0;
2385                 dmz_free_mblock(zmd, mblk);
2386         }
2387 
2388         /* Free the zone descriptors */
2389         dmz_drop_zones(zmd);
2390 
2391         mutex_destroy(&zmd->mblk_flush_lock);
2392         mutex_destroy(&zmd->map_lock);
2393 }
2394 
2395 /*
2396  * Initialize the zoned metadata.
2397  */
2398 int dmz_ctr_metadata(struct dmz_dev *dev, struct dmz_metadata **metadata)
2399 {
2400         struct dmz_metadata *zmd;
2401         unsigned int i, zid;
2402         struct dm_zone *zone;
2403         int ret;
2404 
2405         zmd = kzalloc(sizeof(struct dmz_metadata), GFP_KERNEL);
2406         if (!zmd)
2407                 return -ENOMEM;
2408 
2409         zmd->dev = dev;
2410         zmd->mblk_rbtree = RB_ROOT;
2411         init_rwsem(&zmd->mblk_sem);
2412         mutex_init(&zmd->mblk_flush_lock);
2413         spin_lock_init(&zmd->mblk_lock);
2414         INIT_LIST_HEAD(&zmd->mblk_lru_list);
2415         INIT_LIST_HEAD(&zmd->mblk_dirty_list);
2416 
2417         mutex_init(&zmd->map_lock);
2418         atomic_set(&zmd->unmap_nr_rnd, 0);
2419         INIT_LIST_HEAD(&zmd->unmap_rnd_list);
2420         INIT_LIST_HEAD(&zmd->map_rnd_list);
2421 
2422         atomic_set(&zmd->unmap_nr_seq, 0);
2423         INIT_LIST_HEAD(&zmd->unmap_seq_list);
2424         INIT_LIST_HEAD(&zmd->map_seq_list);
2425 
2426         atomic_set(&zmd->nr_reserved_seq_zones, 0);
2427         INIT_LIST_HEAD(&zmd->reserved_seq_zones_list);
2428 
2429         init_waitqueue_head(&zmd->free_wq);
2430 
2431         /* Initialize zone descriptors */
2432         ret = dmz_init_zones(zmd);
2433         if (ret)
2434                 goto err;
2435 
2436         /* Get super block */
2437         ret = dmz_load_sb(zmd);
2438         if (ret)
2439                 goto err;
2440 
2441         /* Set metadata zones starting from sb_zone */
2442         zid = dmz_id(zmd, zmd->sb_zone);
2443         for (i = 0; i < zmd->nr_meta_zones << 1; i++) {
2444                 zone = dmz_get(zmd, zid + i);
2445                 if (!dmz_is_rnd(zone))
2446                         goto err;
2447                 set_bit(DMZ_META, &zone->flags);
2448         }
2449 
2450         /* Load mapping table */
2451         ret = dmz_load_mapping(zmd);
2452         if (ret)
2453                 goto err;
2454 
2455         /*
2456          * Cache size boundaries: allow at least 2 super blocks, the chunk map
2457          * blocks and enough blocks to be able to cache the bitmap blocks of
2458          * up to 16 zones when idle (min_nr_mblks). Otherwise, if busy, allow
2459          * the cache to add 512 more metadata blocks.
2460          */
2461         zmd->min_nr_mblks = 2 + zmd->nr_map_blocks + zmd->zone_nr_bitmap_blocks * 16;
2462         zmd->max_nr_mblks = zmd->min_nr_mblks + 512;
2463         zmd->mblk_shrinker.count_objects = dmz_mblock_shrinker_count;
2464         zmd->mblk_shrinker.scan_objects = dmz_mblock_shrinker_scan;
2465         zmd->mblk_shrinker.seeks = DEFAULT_SEEKS;
2466 
2467         /* Metadata cache shrinker */
2468         ret = register_shrinker(&zmd->mblk_shrinker);
2469         if (ret) {
2470                 dmz_dev_err(dev, "Register metadata cache shrinker failed");
2471                 goto err;
2472         }
2473 
2474         dmz_dev_info(dev, "Host-%s zoned block device",
2475                      bdev_zoned_model(dev->bdev) == BLK_ZONED_HA ?
2476                      "aware" : "managed");
2477         dmz_dev_info(dev, "  %llu 512-byte logical sectors",
2478                      (u64)dev->capacity);
2479         dmz_dev_info(dev, "  %u zones of %llu 512-byte logical sectors",
2480                      dev->nr_zones, (u64)dev->zone_nr_sectors);
2481         dmz_dev_info(dev, "  %u metadata zones",
2482                      zmd->nr_meta_zones * 2);
2483         dmz_dev_info(dev, "  %u data zones for %u chunks",
2484                      zmd->nr_data_zones, zmd->nr_chunks);
2485         dmz_dev_info(dev, "    %u random zones (%u unmapped)",
2486                      zmd->nr_rnd, atomic_read(&zmd->unmap_nr_rnd));
2487         dmz_dev_info(dev, "    %u sequential zones (%u unmapped)",
2488                      zmd->nr_seq, atomic_read(&zmd->unmap_nr_seq));
2489         dmz_dev_info(dev, "  %u reserved sequential data zones",
2490                      zmd->nr_reserved_seq);
2491 
2492         dmz_dev_debug(dev, "Format:");
2493         dmz_dev_debug(dev, "%u metadata blocks per set (%u max cache)",
2494                       zmd->nr_meta_blocks, zmd->max_nr_mblks);
2495         dmz_dev_debug(dev, "  %u data zone mapping blocks",
2496                       zmd->nr_map_blocks);
2497         dmz_dev_debug(dev, "  %u bitmap blocks",
2498                       zmd->nr_bitmap_blocks);
2499 
2500         *metadata = zmd;
2501 
2502         return 0;
2503 err:
2504         dmz_cleanup_metadata(zmd);
2505         kfree(zmd);
2506         *metadata = NULL;
2507 
2508         return ret;
2509 }
2510 
2511 /*
2512  * Cleanup the zoned metadata resources.
2513  */
2514 void dmz_dtr_metadata(struct dmz_metadata *zmd)
2515 {
2516         unregister_shrinker(&zmd->mblk_shrinker);
2517         dmz_cleanup_metadata(zmd);
2518         kfree(zmd);
2519 }
2520 
2521 /*
2522  * Check zone information on resume.
2523  */
2524 int dmz_resume_metadata(struct dmz_metadata *zmd)
2525 {
2526         struct dmz_dev *dev = zmd->dev;
2527         struct dm_zone *zone;
2528         sector_t wp_block;
2529         unsigned int i;
2530         int ret;
2531 
2532         /* Check zones */
2533         for (i = 0; i < dev->nr_zones; i++) {
2534                 zone = dmz_get(zmd, i);
2535                 if (!zone) {
2536                         dmz_dev_err(dev, "Unable to get zone %u", i);
2537                         return -EIO;
2538                 }
2539 
2540                 wp_block = zone->wp_block;
2541 
2542                 ret = dmz_update_zone(zmd, zone);
2543                 if (ret) {
2544                         dmz_dev_err(dev, "Broken zone %u", i);
2545                         return ret;
2546                 }
2547 
2548                 if (dmz_is_offline(zone)) {
2549                         dmz_dev_warn(dev, "Zone %u is offline", i);
2550                         continue;
2551                 }
2552 
2553                 /* Check write pointer */
2554                 if (!dmz_is_seq(zone))
2555                         zone->wp_block = 0;
2556                 else if (zone->wp_block != wp_block) {
2557                         dmz_dev_err(dev, "Zone %u: Invalid wp (%llu / %llu)",
2558                                     i, (u64)zone->wp_block, (u64)wp_block);
2559                         zone->wp_block = wp_block;
2560                         dmz_invalidate_blocks(zmd, zone, zone->wp_block,
2561                                               dev->zone_nr_blocks - zone->wp_block);
2562                 }
2563         }
2564 
2565         return 0;
2566 }
/* [<][>][^][v][top][bottom][index][help] */
root/drivers/md/dm-zoned-metadata.c

DEFINITIONS
