/* * Copyright (C) 2017 Western Digital Corporation or its affiliates. * * This file is released under the GPL. */ #include "dm-zoned.h" #include #include #define DM_MSG_PREFIX "zoned metadata" /* * Metadata version. */ #define DMZ_META_VER 1 /* * On-disk super block magic. */ #define DMZ_MAGIC ((((unsigned int)('D')) << 24) | \ (((unsigned int)('Z')) << 16) | \ (((unsigned int)('B')) << 8) | \ ((unsigned int)('D'))) /* * On disk super block. * This uses only 512 B but uses on disk a full 4KB block. This block is * followed on disk by the mapping table of chunks to zones and the bitmap * blocks indicating zone block validity. * The overall resulting metadata format is: * (1) Super block (1 block) * (2) Chunk mapping table (nr_map_blocks) * (3) Bitmap blocks (nr_bitmap_blocks) * All metadata blocks are stored in conventional zones, starting from the * the first conventional zone found on disk. */ struct dmz_super { /* Magic number */ __le32 magic; /* 4 */ /* Metadata version number */ __le32 version; /* 8 */ /* Generation number */ __le64 gen; /* 16 */ /* This block number */ __le64 sb_block; /* 24 */ /* The number of metadata blocks, including this super block */ __le32 nr_meta_blocks; /* 28 */ /* The number of sequential zones reserved for reclaim */ __le32 nr_reserved_seq; /* 32 */ /* The number of entries in the mapping table */ __le32 nr_chunks; /* 36 */ /* The number of blocks used for the chunk mapping table */ __le32 nr_map_blocks; /* 40 */ /* The number of blocks used for the block bitmaps */ __le32 nr_bitmap_blocks; /* 44 */ /* Checksum */ __le32 crc; /* 48 */ /* Padding to full 512B sector */ u8 reserved[464]; /* 512 */ }; /* * Chunk mapping entry: entries are indexed by chunk number * and give the zone ID (dzone_id) mapping the chunk on disk. * This zone may be sequential or random. If it is a sequential * zone, a second zone (bzone_id) used as a write buffer may * also be specified. This second zone will always be a randomly * writeable zone. */ struct dmz_map { __le32 dzone_id; __le32 bzone_id; }; /* * Chunk mapping table metadata: 512 8-bytes entries per 4KB block. */ #define DMZ_MAP_ENTRIES (DMZ_BLOCK_SIZE / sizeof(struct dmz_map)) #define DMZ_MAP_ENTRIES_SHIFT (ilog2(DMZ_MAP_ENTRIES)) #define DMZ_MAP_ENTRIES_MASK (DMZ_MAP_ENTRIES - 1) #define DMZ_MAP_UNMAPPED UINT_MAX /* * Meta data block descriptor (for cached metadata blocks). */ struct dmz_mblock { struct rb_node node; struct list_head link; sector_t no; unsigned int ref; unsigned long state; struct page *page; void *data; }; /* * Metadata block state flags. */ enum { DMZ_META_DIRTY, DMZ_META_READING, DMZ_META_WRITING, DMZ_META_ERROR, }; /* * Super block information (one per metadata set). */ struct dmz_sb { sector_t block; struct dmz_mblock *mblk; struct dmz_super *sb; }; /* * In-memory metadata. */ struct dmz_metadata { struct dmz_dev *dev; sector_t zone_bitmap_size; unsigned int zone_nr_bitmap_blocks; unsigned int nr_bitmap_blocks; unsigned int nr_map_blocks; unsigned int nr_useable_zones; unsigned int nr_meta_blocks; unsigned int nr_meta_zones; unsigned int nr_data_zones; unsigned int nr_rnd_zones; unsigned int nr_reserved_seq; unsigned int nr_chunks; /* Zone information array */ struct dm_zone *zones; struct dm_zone *sb_zone; struct dmz_sb sb[2]; unsigned int mblk_primary; u64 sb_gen; unsigned int min_nr_mblks; unsigned int max_nr_mblks; atomic_t nr_mblks; struct rw_semaphore mblk_sem; struct mutex mblk_flush_lock; spinlock_t mblk_lock; struct rb_root mblk_rbtree; struct list_head mblk_lru_list; struct list_head mblk_dirty_list; struct shrinker mblk_shrinker; /* Zone allocation management */ struct mutex map_lock; struct dmz_mblock **map_mblk; unsigned int nr_rnd; atomic_t unmap_nr_rnd; struct list_head unmap_rnd_list; struct list_head map_rnd_list; unsigned int nr_seq; atomic_t unmap_nr_seq; struct list_head unmap_seq_list; struct list_head map_seq_list; atomic_t nr_reserved_seq_zones; struct list_head reserved_seq_zones_list; wait_queue_head_t free_wq; }; /* * Various accessors */ unsigned int dmz_id(struct dmz_metadata *zmd, struct dm_zone *zone) { return ((unsigned int)(zone - zmd->zones)); } sector_t dmz_start_sect(struct dmz_metadata *zmd, struct dm_zone *zone) { return (sector_t)dmz_id(zmd, zone) << zmd->dev->zone_nr_sectors_shift; } sector_t dmz_start_block(struct dmz_metadata *zmd, struct dm_zone *zone) { return (sector_t)dmz_id(zmd, zone) << zmd->dev->zone_nr_blocks_shift; } unsigned int dmz_nr_chunks(struct dmz_metadata *zmd) { return zmd->nr_chunks; } unsigned int dmz_nr_rnd_zones(struct dmz_metadata *zmd) { return zmd->nr_rnd; } unsigned int dmz_nr_unmap_rnd_zones(struct dmz_metadata *zmd) { return atomic_read(&zmd->unmap_nr_rnd); } /* * Lock/unlock mapping table. * The map lock also protects all the zone lists. */ void dmz_lock_map(struct dmz_metadata *zmd) { mutex_lock(&zmd->map_lock); } void dmz_unlock_map(struct dmz_metadata *zmd) { mutex_unlock(&zmd->map_lock); } /* * Lock/unlock metadata access. This is a "read" lock on a semaphore * that prevents metadata flush from running while metadata are being * modified. The actual metadata write mutual exclusion is achieved with * the map lock and zone styate management (active and reclaim state are * mutually exclusive). */ void dmz_lock_metadata(struct dmz_metadata *zmd) { down_read(&zmd->mblk_sem); } void dmz_unlock_metadata(struct dmz_metadata *zmd) { up_read(&zmd->mblk_sem); } /* * Lock/unlock flush: prevent concurrent executions * of dmz_flush_metadata as well as metadata modification in reclaim * while flush is being executed. */ void dmz_lock_flush(struct dmz_metadata *zmd) { mutex_lock(&zmd->mblk_flush_lock); } void dmz_unlock_flush(struct dmz_metadata *zmd) { mutex_unlock(&zmd->mblk_flush_lock); } /* * Allocate a metadata block. */ static struct dmz_mblock *dmz_alloc_mblock(struct dmz_metadata *zmd, sector_t mblk_no) { struct dmz_mblock *mblk = NULL; /* See if we can reuse cached blocks */ if (zmd->max_nr_mblks && atomic_read(&zmd->nr_mblks) > zmd->max_nr_mblks) { spin_lock(&zmd->mblk_lock); mblk = list_first_entry_or_null(&zmd->mblk_lru_list, struct dmz_mblock, link); if (mblk) { list_del_init(&mblk->link); rb_erase(&mblk->node, &zmd->mblk_rbtree); mblk->no = mblk_no; } spin_unlock(&zmd->mblk_lock); if (mblk) return mblk; } /* Allocate a new block */ mblk = kmalloc(sizeof(struct dmz_mblock), GFP_NOIO); if (!mblk) return NULL; mblk->page = alloc_page(GFP_NOIO); if (!mblk->page) { kfree(mblk); return NULL; } RB_CLEAR_NODE(&mblk->node); INIT_LIST_HEAD(&mblk->link); mblk->ref = 0; mblk->state = 0; mblk->no = mblk_no; mblk->data = page_address(mblk->page); atomic_inc(&zmd->nr_mblks); return mblk; } /* * Free a metadata block. */ static void dmz_free_mblock(struct dmz_metadata *zmd, struct dmz_mblock *mblk) { __free_pages(mblk->page, 0); kfree(mblk); atomic_dec(&zmd->nr_mblks); } /* * Insert a metadata block in the rbtree. */ static void dmz_insert_mblock(struct dmz_metadata *zmd, struct dmz_mblock *mblk) { struct rb_root *root = &zmd->mblk_rbtree; struct rb_node **new = &(root->rb_node), *parent = NULL; struct dmz_mblock *b; /* Figure out where to put the new node */ while (*new) { b = container_of(*new, struct dmz_mblock, node); parent = *new; new = (b->no < mblk->no) ? &((*new)->rb_left) : &((*new)->rb_right); } /* Add new node and rebalance tree */ rb_link_node(&mblk->node, parent, new); rb_insert_color(&mblk->node, root); } /* * Lookup a metadata block in the rbtree. If the block is found, increment * its reference count. */ static struct dmz_mblock *dmz_get_mblock_fast(struct dmz_metadata *zmd, sector_t mblk_no) { struct rb_root *root = &zmd->mblk_rbtree; struct rb_node *node = root->rb_node; struct dmz_mblock *mblk; while (node) { mblk = container_of(node, struct dmz_mblock, node); if (mblk->no == mblk_no) { /* * If this is the first reference to the block, * remove it from the LRU list. */ mblk->ref++; if (mblk->ref == 1 && !test_bit(DMZ_META_DIRTY, &mblk->state)) list_del_init(&mblk->link); return mblk; } node = (mblk->no < mblk_no) ? node->rb_left : node->rb_right; } return NULL; } /* * Metadata block BIO end callback. */ static void dmz_mblock_bio_end_io(struct bio *bio) { struct dmz_mblock *mblk = bio->bi_private; int flag; if (bio->bi_status) set_bit(DMZ_META_ERROR, &mblk->state); if (bio_op(bio) == REQ_OP_WRITE) flag = DMZ_META_WRITING; else flag = DMZ_META_READING; clear_bit_unlock(flag, &mblk->state); smp_mb__after_atomic(); wake_up_bit(&mblk->state, flag); bio_put(bio); } /* * Read an uncached metadata block from disk and add it to the cache. */ static struct dmz_mblock *dmz_get_mblock_slow(struct dmz_metadata *zmd, sector_t mblk_no) { struct dmz_mblock *mblk, *m; sector_t block = zmd->sb[zmd->mblk_primary].block + mblk_no; struct bio *bio; /* Get a new block and a BIO to read it */ mblk = dmz_alloc_mblock(zmd, mblk_no); if (!mblk) return NULL; bio = bio_alloc(GFP_NOIO, 1); if (!bio) { dmz_free_mblock(zmd, mblk); return NULL; } spin_lock(&zmd->mblk_lock); /* * Make sure that another context did not start reading * the block already. */ m = dmz_get_mblock_fast(zmd, mblk_no); if (m) { spin_unlock(&zmd->mblk_lock); dmz_free_mblock(zmd, mblk); bio_put(bio); return m; } mblk->ref++; set_bit(DMZ_META_READING, &mblk->state); dmz_insert_mblock(zmd, mblk); spin_unlock(&zmd->mblk_lock); /* Submit read BIO */ bio->bi_iter.bi_sector = dmz_blk2sect(block); bio_set_dev(bio, zmd->dev->bdev); bio->bi_private = mblk; bio->bi_end_io = dmz_mblock_bio_end_io; bio_set_op_attrs(bio, REQ_OP_READ, REQ_META | REQ_PRIO); bio_add_page(bio, mblk->page, DMZ_BLOCK_SIZE, 0); submit_bio(bio); return mblk; } /* * Free metadata blocks. */ static unsigned long dmz_shrink_mblock_cache(struct dmz_metadata *zmd, unsigned long limit) { struct dmz_mblock *mblk; unsigned long count = 0; if (!zmd->max_nr_mblks) return 0; while (!list_empty(&zmd->mblk_lru_list) && atomic_read(&zmd->nr_mblks) > zmd->min_nr_mblks && count < limit) { mblk = list_first_entry(&zmd->mblk_lru_list, struct dmz_mblock, link); list_del_init(&mblk->link); rb_erase(&mblk->node, &zmd->mblk_rbtree); dmz_free_mblock(zmd, mblk); count++; } return count; } /* * For mblock shrinker: get the number of unused metadata blocks in the cache. */ static unsigned long dmz_mblock_shrinker_count(struct shrinker *shrink, struct shrink_control *sc) { struct dmz_metadata *zmd = container_of(shrink, struct dmz_metadata, mblk_shrinker); return atomic_read(&zmd->nr_mblks); } /* * For mblock shrinker: scan unused metadata blocks and shrink the cache. */ static unsigned long dmz_mblock_shrinker_scan(struct shrinker *shrink, struct shrink_control *sc) { struct dmz_metadata *zmd = container_of(shrink, struct dmz_metadata, mblk_shrinker); unsigned long count; spin_lock(&zmd->mblk_lock); count = dmz_shrink_mblock_cache(zmd, sc->nr_to_scan); spin_unlock(&zmd->mblk_lock); return count ? count : SHRINK_STOP; } /* * Release a metadata block. */ static void dmz_release_mblock(struct dmz_metadata *zmd, struct dmz_mblock *mblk) { if (!mblk) return; spin_lock(&zmd->mblk_lock); mblk->ref--; if (mblk->ref == 0) { if (test_bit(DMZ_META_ERROR, &mblk->state)) { rb_erase(&mblk->node, &zmd->mblk_rbtree); dmz_free_mblock(zmd, mblk); } else if (!test_bit(DMZ_META_DIRTY, &mblk->state)) { list_add_tail(&mblk->link, &zmd->mblk_lru_list); dmz_shrink_mblock_cache(zmd, 1); } } spin_unlock(&zmd->mblk_lock); } /* * Get a metadata block from the rbtree. If the block * is not present, read it from disk. */ static struct dmz_mblock *dmz_get_mblock(struct dmz_metadata *zmd, sector_t mblk_no) { struct dmz_mblock *mblk; /* Check rbtree */ spin_lock(&zmd->mblk_lock); mblk = dmz_get_mblock_fast(zmd, mblk_no); spin_unlock(&zmd->mblk_lock); if (!mblk) { /* Cache miss: read the block from disk */ mblk = dmz_get_mblock_slow(zmd, mblk_no); if (!mblk) return ERR_PTR(-ENOMEM); } /* Wait for on-going read I/O and check for error */ wait_on_bit_io(&mblk->state, DMZ_META_READING, TASK_UNINTERRUPTIBLE); if (test_bit(DMZ_META_ERROR, &mblk->state)) { dmz_release_mblock(zmd, mblk); return ERR_PTR(-EIO); } return mblk; } /* * Mark a metadata block dirty. */ static void dmz_dirty_mblock(struct dmz_metadata *zmd, struct dmz_mblock *mblk) { spin_lock(&zmd->mblk_lock); if (!test_and_set_bit(DMZ_META_DIRTY, &mblk->state)) list_add_tail(&mblk->link, &zmd->mblk_dirty_list); spin_unlock(&zmd->mblk_lock); } /* * Issue a metadata block write BIO. */ static void dmz_write_mblock(struct dmz_metadata *zmd, struct dmz_mblock *mblk, unsigned int set) { sector_t block = zmd->sb[set].block + mblk->no; struct bio *bio; bio = bio_alloc(GFP_NOIO, 1); if (!bio) { set_bit(DMZ_META_ERROR, &mblk->state); return; } set_bit(DMZ_META_WRITING, &mblk->state); bio->bi_iter.bi_sector = dmz_blk2sect(block); bio_set_dev(bio, zmd->dev->bdev); bio->bi_private = mblk; bio->bi_end_io = dmz_mblock_bio_end_io; bio_set_op_attrs(bio, REQ_OP_WRITE, REQ_META | REQ_PRIO); bio_add_page(bio, mblk->page, DMZ_BLOCK_SIZE, 0); submit_bio(bio); } /* * Read/write a metadata block. */ static int dmz_rdwr_block(struct dmz_metadata *zmd, int op, sector_t block, struct page *page) { struct bio *bio; int ret; bio = bio_alloc(GFP_NOIO, 1); if (!bio) return -ENOMEM; bio->bi_iter.bi_sector = dmz_blk2sect(block); bio_set_dev(bio, zmd->dev->bdev); bio_set_op_attrs(bio, op, REQ_SYNC | REQ_META | REQ_PRIO); bio_add_page(bio, page, DMZ_BLOCK_SIZE, 0); ret = submit_bio_wait(bio); bio_put(bio); return ret; } /* * Write super block of the specified metadata set. */ static int dmz_write_sb(struct dmz_metadata *zmd, unsigned int set) { sector_t block = zmd->sb[set].block; struct dmz_mblock *mblk = zmd->sb[set].mblk; struct dmz_super *sb = zmd->sb[set].sb; u64 sb_gen = zmd->sb_gen + 1; int ret; sb->magic = cpu_to_le32(DMZ_MAGIC); sb->version = cpu_to_le32(DMZ_META_VER); sb->gen = cpu_to_le64(sb_gen); sb->sb_block = cpu_to_le64(block); sb->nr_meta_blocks = cpu_to_le32(zmd->nr_meta_blocks); sb->nr_reserved_seq = cpu_to_le32(zmd->nr_reserved_seq); sb->nr_chunks = cpu_to_le32(zmd->nr_chunks); sb->nr_map_blocks = cpu_to_le32(zmd->nr_map_blocks); sb->nr_bitmap_blocks = cpu_to_le32(zmd->nr_bitmap_blocks); sb->crc = 0; sb->crc = cpu_to_le32(crc32_le(sb_gen, (unsigned char *)sb, DMZ_BLOCK_SIZE)); ret = dmz_rdwr_block(zmd, REQ_OP_WRITE, block, mblk->page); if (ret == 0) ret = blkdev_issue_flush(zmd->dev->bdev, GFP_NOIO, NULL); return ret; } /* * Write dirty metadata blocks to the specified set. */ static int dmz_write_dirty_mblocks(struct dmz_metadata *zmd, struct list_head *write_list, unsigned int set) { struct dmz_mblock *mblk; struct blk_plug plug; int ret = 0; /* Issue writes */ blk_start_plug(&plug); list_for_each_entry(mblk, write_list, link) dmz_write_mblock(zmd, mblk, set); blk_finish_plug(&plug); /* Wait for completion */ list_for_each_entry(mblk, write_list, link) { wait_on_bit_io(&mblk->state, DMZ_META_WRITING, TASK_UNINTERRUPTIBLE); if (test_bit(DMZ_META_ERROR, &mblk->state)) { clear_bit(DMZ_META_ERROR, &mblk->state); ret = -EIO; } } /* Flush drive cache (this will also sync data) */ if (ret == 0) ret = blkdev_issue_flush(zmd->dev->bdev, GFP_NOIO, NULL); return ret; } /* * Log dirty metadata blocks. */ static int dmz_log_dirty_mblocks(struct dmz_metadata *zmd, struct list_head *write_list) { unsigned int log_set = zmd->mblk_primary ^ 0x1; int ret; /* Write dirty blocks to the log */ ret = dmz_write_dirty_mblocks(zmd, write_list, log_set); if (ret) return ret; /* * No error so far: now validate the log by updating the * log index super block generation. */ ret = dmz_write_sb(zmd, log_set); if (ret) return ret; return 0; } /* * Flush dirty metadata blocks. */ int dmz_flush_metadata(struct dmz_metadata *zmd) { struct dmz_mblock *mblk; struct list_head write_list; int ret; if (WARN_ON(!zmd)) return 0; INIT_LIST_HEAD(&write_list); /* * Make sure that metadata blocks are stable before logging: take * the write lock on the metadata semaphore to prevent target BIOs * from modifying metadata. */ down_write(&zmd->mblk_sem); /* * This is called from the target flush work and reclaim work. * Concurrent execution is not allowed. */ dmz_lock_flush(zmd); /* Get dirty blocks */ spin_lock(&zmd->mblk_lock); list_splice_init(&zmd->mblk_dirty_list, &write_list); spin_unlock(&zmd->mblk_lock); /* If there are no dirty metadata blocks, just flush the device cache */ if (list_empty(&write_list)) { ret = blkdev_issue_flush(zmd->dev->bdev, GFP_NOIO, NULL); goto out; } /* * The primary metadata set is still clean. Keep it this way until * all updates are successful in the secondary set. That is, use * the secondary set as a log. */ ret = dmz_log_dirty_mblocks(zmd, &write_list); if (ret) goto out; /* * The log is on disk. It is now safe to update in place * in the primary metadata set. */ ret = dmz_write_dirty_mblocks(zmd, &write_list, zmd->mblk_primary); if (ret) goto out; ret = dmz_write_sb(zmd, zmd->mblk_primary); if (ret) goto out; while (!list_empty(&write_list)) { mblk = list_first_entry(&write_list, struct dmz_mblock, link); list_del_init(&mblk->link); spin_lock(&zmd->mblk_lock); clear_bit(DMZ_META_DIRTY, &mblk->state); if (mblk->ref == 0) list_add_tail(&mblk->link, &zmd->mblk_lru_list); spin_unlock(&zmd->mblk_lock); } zmd->sb_gen++; out: if (ret && !list_empty(&write_list)) { spin_lock(&zmd->mblk_lock); list_splice(&write_list, &zmd->mblk_dirty_list); spin_unlock(&zmd->mblk_lock); } dmz_unlock_flush(zmd); up_write(&zmd->mblk_sem); return ret; } /* * Check super block. */ static int dmz_check_sb(struct dmz_metadata *zmd, struct dmz_super *sb) { unsigned int nr_meta_zones, nr_data_zones; struct dmz_dev *dev = zmd->dev; u32 crc, stored_crc; u64 gen; gen = le64_to_cpu(sb->gen); stored_crc = le32_to_cpu(sb->crc); sb->crc = 0; crc = crc32_le(gen, (unsigned char *)sb, DMZ_BLOCK_SIZE); if (crc != stored_crc) { dmz_dev_err(dev, "Invalid checksum (needed 0x%08x, got 0x%08x)", crc, stored_crc); return -ENXIO; } if (le32_to_cpu(sb->magic) != DMZ_MAGIC) { dmz_dev_err(dev, "Invalid meta magic (needed 0x%08x, got 0x%08x)", DMZ_MAGIC, le32_to_cpu(sb->magic)); return -ENXIO; } if (le32_to_cpu(sb->version) != DMZ_META_VER) { dmz_dev_err(dev, "Invalid meta version (needed %d, got %d)", DMZ_META_VER, le32_to_cpu(sb->version)); return -ENXIO; } nr_meta_zones = (le32_to_cpu(sb->nr_meta_blocks) + dev->zone_nr_blocks - 1) >> dev->zone_nr_blocks_shift; if (!nr_meta_zones || nr_meta_zones >= zmd->nr_rnd_zones) { dmz_dev_err(dev, "Invalid number of metadata blocks"); return -ENXIO; } if (!le32_to_cpu(sb->nr_reserved_seq) || le32_to_cpu(sb->nr_reserved_seq) >= (zmd->nr_useable_zones - nr_meta_zones)) { dmz_dev_err(dev, "Invalid number of reserved sequential zones"); return -ENXIO; } nr_data_zones = zmd->nr_useable_zones - (nr_meta_zones * 2 + le32_to_cpu(sb->nr_reserved_seq)); if (le32_to_cpu(sb->nr_chunks) > nr_data_zones) { dmz_dev_err(dev, "Invalid number of chunks %u / %u", le32_to_cpu(sb->nr_chunks), nr_data_zones); return -ENXIO; } /* OK */ zmd->nr_meta_blocks = le32_to_cpu(sb->nr_meta_blocks); zmd->nr_reserved_seq = le32_to_cpu(sb->nr_reserved_seq); zmd->nr_chunks = le32_to_cpu(sb->nr_chunks); zmd->nr_map_blocks = le32_to_cpu(sb->nr_map_blocks); zmd->nr_bitmap_blocks = le32_to_cpu(sb->nr_bitmap_blocks); zmd->nr_meta_zones = nr_meta_zones; zmd->nr_data_zones = nr_data_zones; return 0; } /* * Read the first or second super block from disk. */ static int dmz_read_sb(struct dmz_metadata *zmd, unsigned int set) { return dmz_rdwr_block(zmd, REQ_OP_READ, zmd->sb[set].block, zmd->sb[set].mblk->page); } /* * Determine the position of the secondary super blocks on disk. * This is used only if a corruption of the primary super block * is detected. */ static int dmz_lookup_secondary_sb(struct dmz_metadata *zmd) { unsigned int zone_nr_blocks = zmd->dev->zone_nr_blocks; struct dmz_mblock *mblk; int i; /* Allocate a block */ mblk = dmz_alloc_mblock(zmd, 0); if (!mblk) return -ENOMEM; zmd->sb[1].mblk = mblk; zmd->sb[1].sb = mblk->data; /* Bad first super block: search for the second one */ zmd->sb[1].block = zmd->sb[0].block + zone_nr_blocks; for (i = 0; i < zmd->nr_rnd_zones - 1; i++) { if (dmz_read_sb(zmd, 1) != 0) break; if (le32_to_cpu(zmd->sb[1].sb->magic) == DMZ_MAGIC) return 0; zmd->sb[1].block += zone_nr_blocks; } dmz_free_mblock(zmd, mblk); zmd->sb[1].mblk = NULL; return -EIO; } /* * Read the first or second super block from disk. */ static int dmz_get_sb(struct dmz_metadata *zmd, unsigned int set) { struct dmz_mblock *mblk; int ret; /* Allocate a block */ mblk = dmz_alloc_mblock(zmd, 0); if (!mblk) return -ENOMEM; zmd->sb[set].mblk = mblk; zmd->sb[set].sb = mblk->data; /* Read super block */ ret = dmz_read_sb(zmd, set); if (ret) { dmz_free_mblock(zmd, mblk); zmd->sb[set].mblk = NULL; return ret; } return 0; } /* * Recover a metadata set. */ static int dmz_recover_mblocks(struct dmz_metadata *zmd, unsigned int dst_set) { unsigned int src_set = dst_set ^ 0x1; struct page *page; int i, ret; dmz_dev_warn(zmd->dev, "Metadata set %u invalid: recovering", dst_set); if (dst_set == 0) zmd->sb[0].block = dmz_start_block(zmd, zmd->sb_zone); else { zmd->sb[1].block = zmd->sb[0].block + (zmd->nr_meta_zones << zmd->dev->zone_nr_blocks_shift); } page = alloc_page(GFP_NOIO); if (!page) return -ENOMEM; /* Copy metadata blocks */ for (i = 1; i < zmd->nr_meta_blocks; i++) { ret = dmz_rdwr_block(zmd, REQ_OP_READ, zmd->sb[src_set].block + i, page); if (ret) goto out; ret = dmz_rdwr_block(zmd, REQ_OP_WRITE, zmd->sb[dst_set].block + i, page); if (ret) goto out; } /* Finalize with the super block */ if (!zmd->sb[dst_set].mblk) { zmd->sb[dst_set].mblk = dmz_alloc_mblock(zmd, 0); if (!zmd->sb[dst_set].mblk) { ret = -ENOMEM; goto out; } zmd->sb[dst_set].sb = zmd->sb[dst_set].mblk->data; } ret = dmz_write_sb(zmd, dst_set); out: __free_pages(page, 0); return ret; } /* * Get super block from disk. */ static int dmz_load_sb(struct dmz_metadata *zmd) { bool sb_good[2] = {false, false}; u64 sb_gen[2] = {0, 0}; int ret; /* Read and check the primary super block */ zmd->sb[0].block = dmz_start_block(zmd, zmd->sb_zone); ret = dmz_get_sb(zmd, 0); if (ret) { dmz_dev_err(zmd->dev, "Read primary super block failed"); return ret; } ret = dmz_check_sb(zmd, zmd->sb[0].sb); /* Read and check secondary super block */ if (ret == 0) { sb_good[0] = true; zmd->sb[1].block = zmd->sb[0].block + (zmd->nr_meta_zones << zmd->dev->zone_nr_blocks_shift); ret = dmz_get_sb(zmd, 1); } else ret = dmz_lookup_secondary_sb(zmd); if (ret) { dmz_dev_err(zmd->dev, "Read secondary super block failed"); return ret; } ret = dmz_check_sb(zmd, zmd->sb[1].sb); if (ret == 0) sb_good[1] = true; /* Use highest generation sb first */ if (!sb_good[0] && !sb_good[1]) { dmz_dev_err(zmd->dev, "No valid super block found"); return -EIO; } if (sb_good[0]) sb_gen[0] = le64_to_cpu(zmd->sb[0].sb->gen); else ret = dmz_recover_mblocks(zmd, 0); if (sb_good[1]) sb_gen[1] = le64_to_cpu(zmd->sb[1].sb->gen); else ret = dmz_recover_mblocks(zmd, 1); if (ret) { dmz_dev_err(zmd->dev, "Recovery failed"); return -EIO; } if (sb_gen[0] >= sb_gen[1]) { zmd->sb_gen = sb_gen[0]; zmd->mblk_primary = 0; } else { zmd->sb_gen = sb_gen[1]; zmd->mblk_primary = 1; } dmz_dev_debug(zmd->dev, "Using super block %u (gen %llu)", zmd->mblk_primary, zmd->sb_gen); return 0; } /* * Initialize a zone descriptor. */ static int dmz_init_zone(struct dmz_metadata *zmd, struct dm_zone *zone, struct blk_zone *blkz) { struct dmz_dev *dev = zmd->dev; /* Ignore the eventual last runt (smaller) zone */ if (blkz->len != dev->zone_nr_sectors) { if (blkz->start + blkz->len == dev->capacity) return 0; return -ENXIO; } INIT_LIST_HEAD(&zone->link); atomic_set(&zone->refcount, 0); zone->chunk = DMZ_MAP_UNMAPPED; if (blkz->type == BLK_ZONE_TYPE_CONVENTIONAL) { set_bit(DMZ_RND, &zone->flags); zmd->nr_rnd_zones++; } else if (blkz->type == BLK_ZONE_TYPE_SEQWRITE_REQ || blkz->type == BLK_ZONE_TYPE_SEQWRITE_PREF) { set_bit(DMZ_SEQ, &zone->flags); } else return -ENXIO; if (blkz->cond == BLK_ZONE_COND_OFFLINE) set_bit(DMZ_OFFLINE, &zone->flags); else if (blkz->cond == BLK_ZONE_COND_READONLY) set_bit(DMZ_READ_ONLY, &zone->flags); if (dmz_is_rnd(zone)) zone->wp_block = 0; else zone->wp_block = dmz_sect2blk(blkz->wp - blkz->start); if (!dmz_is_offline(zone) && !dmz_is_readonly(zone)) { zmd->nr_useable_zones++; if (dmz_is_rnd(zone)) { zmd->nr_rnd_zones++; if (!zmd->sb_zone) { /* Super block zone */ zmd->sb_zone = zone; } } } return 0; } /* * Free zones descriptors. */ static void dmz_drop_zones(struct dmz_metadata *zmd) { kfree(zmd->zones); zmd->zones = NULL; } /* * The size of a zone report in number of zones. * This results in 4096*64B=256KB report zones commands. */ #define DMZ_REPORT_NR_ZONES 4096 /* * Allocate and initialize zone descriptors using the zone * information from disk. */ static int dmz_init_zones(struct dmz_metadata *zmd) { struct dmz_dev *dev = zmd->dev; struct dm_zone *zone; struct blk_zone *blkz; unsigned int nr_blkz; sector_t sector = 0; int i, ret = 0; /* Init */ zmd->zone_bitmap_size = dev->zone_nr_blocks >> 3; zmd->zone_nr_bitmap_blocks = zmd->zone_bitmap_size >> DMZ_BLOCK_SHIFT; /* Allocate zone array */ zmd->zones = kcalloc(dev->nr_zones, sizeof(struct dm_zone), GFP_KERNEL); if (!zmd->zones) return -ENOMEM; dmz_dev_info(dev, "Using %zu B for zone information", sizeof(struct dm_zone) * dev->nr_zones); /* Get zone information */ nr_blkz = DMZ_REPORT_NR_ZONES; blkz = kcalloc(nr_blkz, sizeof(struct blk_zone), GFP_KERNEL); if (!blkz) { ret = -ENOMEM; goto out; } /* * Get zone information and initialize zone descriptors. * At the same time, determine where the super block * should be: first block of the first randomly writable * zone. */ zone = zmd->zones; while (sector < dev->capacity) { /* Get zone information */ nr_blkz = DMZ_REPORT_NR_ZONES; ret = blkdev_report_zones(dev->bdev, sector, blkz, &nr_blkz, GFP_KERNEL); if (ret) { dmz_dev_err(dev, "Report zones failed %d", ret); goto out; } if (!nr_blkz) break; /* Process report */ for (i = 0; i < nr_blkz; i++) { ret = dmz_init_zone(zmd, zone, &blkz[i]); if (ret) goto out; sector += dev->zone_nr_sectors; zone++; } } /* The entire zone configuration of the disk should now be known */ if (sector < dev->capacity) { dmz_dev_err(dev, "Failed to get correct zone information"); ret = -ENXIO; } out: kfree(blkz); if (ret) dmz_drop_zones(zmd); return ret; } /* * Update a zone information. */ static int dmz_update_zone(struct dmz_metadata *zmd, struct dm_zone *zone) { unsigned int nr_blkz = 1; struct blk_zone blkz; int ret; /* Get zone information from disk */ ret = blkdev_report_zones(zmd->dev->bdev, dmz_start_sect(zmd, zone), &blkz, &nr_blkz, GFP_NOIO); if (!nr_blkz) ret = -EIO; if (ret) { dmz_dev_err(zmd->dev, "Get zone %u report failed", dmz_id(zmd, zone)); return ret; } clear_bit(DMZ_OFFLINE, &zone->flags); clear_bit(DMZ_READ_ONLY, &zone->flags); if (blkz.cond == BLK_ZONE_COND_OFFLINE) set_bit(DMZ_OFFLINE, &zone->flags); else if (blkz.cond == BLK_ZONE_COND_READONLY) set_bit(DMZ_READ_ONLY, &zone->flags); if (dmz_is_seq(zone)) zone->wp_block = dmz_sect2blk(blkz.wp - blkz.start); else zone->wp_block = 0; return 0; } /* * Check a zone write pointer position when the zone is marked * with the sequential write error flag. */ static int dmz_handle_seq_write_err(struct dmz_metadata *zmd, struct dm_zone *zone) { unsigned int wp = 0; int ret; wp = zone->wp_block; ret = dmz_update_zone(zmd, zone); if (ret) return ret; dmz_dev_warn(zmd->dev, "Processing zone %u write error (zone wp %u/%u)", dmz_id(zmd, zone), zone->wp_block, wp); if (zone->wp_block < wp) { dmz_invalidate_blocks(zmd, zone, zone->wp_block, wp - zone->wp_block); } return 0; } static struct dm_zone *dmz_get(struct dmz_metadata *zmd, unsigned int zone_id) { return &zmd->zones[zone_id]; } /* * Reset a zone write pointer. */ static int dmz_reset_zone(struct dmz_metadata *zmd, struct dm_zone *zone) { int ret; /* * Ignore offline zones, read only zones, * and conventional zones. */ if (dmz_is_offline(zone) || dmz_is_readonly(zone) || dmz_is_rnd(zone)) return 0; if (!dmz_is_empty(zone) || dmz_seq_write_err(zone)) { struct dmz_dev *dev = zmd->dev; ret = blkdev_reset_zones(dev->bdev, dmz_start_sect(zmd, zone), dev->zone_nr_sectors, GFP_NOIO); if (ret) { dmz_dev_err(dev, "Reset zone %u failed %d", dmz_id(zmd, zone), ret); return ret; } } /* Clear write error bit and rewind write pointer position */ clear_bit(DMZ_SEQ_WRITE_ERR, &zone->flags); zone->wp_block = 0; return 0; } static void dmz_get_zone_weight(struct dmz_metadata *zmd, struct dm_zone *zone); /* * Initialize chunk mapping. */ static int dmz_load_mapping(struct dmz_metadata *zmd) { struct dmz_dev *dev = zmd->dev; struct dm_zone *dzone, *bzone; struct dmz_mblock *dmap_mblk = NULL; struct dmz_map *dmap; unsigned int i = 0, e = 0, chunk = 0; unsigned int dzone_id; unsigned int bzone_id; /* Metadata block array for the chunk mapping table */ zmd->map_mblk = kcalloc(zmd->nr_map_blocks, sizeof(struct dmz_mblk *), GFP_KERNEL); if (!zmd->map_mblk) return -ENOMEM; /* Get chunk mapping table blocks and initialize zone mapping */ while (chunk < zmd->nr_chunks) { if (!dmap_mblk) { /* Get mapping block */ dmap_mblk = dmz_get_mblock(zmd, i + 1); if (IS_ERR(dmap_mblk)) return PTR_ERR(dmap_mblk); zmd->map_mblk[i] = dmap_mblk; dmap = (struct dmz_map *) dmap_mblk->data; i++; e = 0; } /* Check data zone */ dzone_id = le32_to_cpu(dmap[e].dzone_id); if (dzone_id == DMZ_MAP_UNMAPPED) goto next; if (dzone_id >= dev->nr_zones) { dmz_dev_err(dev, "Chunk %u mapping: invalid data zone ID %u", chunk, dzone_id); return -EIO; } dzone = dmz_get(zmd, dzone_id); set_bit(DMZ_DATA, &dzone->flags); dzone->chunk = chunk; dmz_get_zone_weight(zmd, dzone); if (dmz_is_rnd(dzone)) list_add_tail(&dzone->link, &zmd->map_rnd_list); else list_add_tail(&dzone->link, &zmd->map_seq_list); /* Check buffer zone */ bzone_id = le32_to_cpu(dmap[e].bzone_id); if (bzone_id == DMZ_MAP_UNMAPPED) goto next; if (bzone_id >= dev->nr_zones) { dmz_dev_err(dev, "Chunk %u mapping: invalid buffer zone ID %u", chunk, bzone_id); return -EIO; } bzone = dmz_get(zmd, bzone_id); if (!dmz_is_rnd(bzone)) { dmz_dev_err(dev, "Chunk %u mapping: invalid buffer zone %u", chunk, bzone_id); return -EIO; } set_bit(DMZ_DATA, &bzone->flags); set_bit(DMZ_BUF, &bzone->flags); bzone->chunk = chunk; bzone->bzone = dzone; dzone->bzone = bzone; dmz_get_zone_weight(zmd, bzone); list_add_tail(&bzone->link, &zmd->map_rnd_list); next: chunk++; e++; if (e >= DMZ_MAP_ENTRIES) dmap_mblk = NULL; } /* * At this point, only meta zones and mapped data zones were * fully initialized. All remaining zones are unmapped data * zones. Finish initializing those here. */ for (i = 0; i < dev->nr_zones; i++) { dzone = dmz_get(zmd, i); if (dmz_is_meta(dzone)) continue; if (dmz_is_rnd(dzone)) zmd->nr_rnd++; else zmd->nr_seq++; if (dmz_is_data(dzone)) { /* Already initialized */ continue; } /* Unmapped data zone */ set_bit(DMZ_DATA, &dzone->flags); dzone->chunk = DMZ_MAP_UNMAPPED; if (dmz_is_rnd(dzone)) { list_add_tail(&dzone->link, &zmd->unmap_rnd_list); atomic_inc(&zmd->unmap_nr_rnd); } else if (atomic_read(&zmd->nr_reserved_seq_zones) < zmd->nr_reserved_seq) { list_add_tail(&dzone->link, &zmd->reserved_seq_zones_list); atomic_inc(&zmd->nr_reserved_seq_zones); zmd->nr_seq--; } else { list_add_tail(&dzone->link, &zmd->unmap_seq_list); atomic_inc(&zmd->unmap_nr_seq); } } return 0; } /* * Set a data chunk mapping. */ static void dmz_set_chunk_mapping(struct dmz_metadata *zmd, unsigned int chunk, unsigned int dzone_id, unsigned int bzone_id) { struct dmz_mblock *dmap_mblk = zmd->map_mblk[chunk >> DMZ_MAP_ENTRIES_SHIFT]; struct dmz_map *dmap = (struct dmz_map *) dmap_mblk->data; int map_idx = chunk & DMZ_MAP_ENTRIES_MASK; dmap[map_idx].dzone_id = cpu_to_le32(dzone_id); dmap[map_idx].bzone_id = cpu_to_le32(bzone_id); dmz_dirty_mblock(zmd, dmap_mblk); } /* * The list of mapped zones is maintained in LRU order. * This rotates a zone at the end of its map list. */ static void __dmz_lru_zone(struct dmz_metadata *zmd, struct dm_zone *zone) { if (list_empty(&zone->link)) return; list_del_init(&zone->link); if (dmz_is_seq(zone)) { /* LRU rotate sequential zone */ list_add_tail(&zone->link, &zmd->map_seq_list); } else { /* LRU rotate random zone */ list_add_tail(&zone->link, &zmd->map_rnd_list); } } /* * The list of mapped random zones is maintained * in LRU order. This rotates a zone at the end of the list. */ static void dmz_lru_zone(struct dmz_metadata *zmd, struct dm_zone *zone) { __dmz_lru_zone(zmd, zone); if (zone->bzone) __dmz_lru_zone(zmd, zone->bzone); } /* * Wait for any zone to be freed. */ static void dmz_wait_for_free_zones(struct dmz_metadata *zmd) { DEFINE_WAIT(wait); prepare_to_wait(&zmd->free_wq, &wait, TASK_UNINTERRUPTIBLE); dmz_unlock_map(zmd); dmz_unlock_metadata(zmd); io_schedule_timeout(HZ); dmz_lock_metadata(zmd); dmz_lock_map(zmd); finish_wait(&zmd->free_wq, &wait); } /* * Lock a zone for reclaim (set the zone RECLAIM bit). * Returns false if the zone cannot be locked or if it is already locked * and 1 otherwise. */ int dmz_lock_zone_reclaim(struct dm_zone *zone) { /* Active zones cannot be reclaimed */ if (dmz_is_active(zone)) return 0; return !test_and_set_bit(DMZ_RECLAIM, &zone->flags); } /* * Clear a zone reclaim flag. */ void dmz_unlock_zone_reclaim(struct dm_zone *zone) { WARN_ON(dmz_is_active(zone)); WARN_ON(!dmz_in_reclaim(zone)); clear_bit_unlock(DMZ_RECLAIM, &zone->flags); smp_mb__after_atomic(); wake_up_bit(&zone->flags, DMZ_RECLAIM); } /* * Wait for a zone reclaim to complete. */ static void dmz_wait_for_reclaim(struct dmz_metadata *zmd, struct dm_zone *zone) { dmz_unlock_map(zmd); dmz_unlock_metadata(zmd); wait_on_bit_timeout(&zone->flags, DMZ_RECLAIM, TASK_UNINTERRUPTIBLE, HZ); dmz_lock_metadata(zmd); dmz_lock_map(zmd); } /* * Select a random write zone for reclaim. */ static struct dm_zone *dmz_get_rnd_zone_for_reclaim(struct dmz_metadata *zmd) { struct dm_zone *dzone = NULL; struct dm_zone *zone; if (list_empty(&zmd->map_rnd_list)) return NULL; list_for_each_entry(zone, &zmd->map_rnd_list, link) { if (dmz_is_buf(zone)) dzone = zone->bzone; else dzone = zone; if (dmz_lock_zone_reclaim(dzone)) return dzone; } return NULL; } /* * Select a buffered sequential zone for reclaim. */ static struct dm_zone *dmz_get_seq_zone_for_reclaim(struct dmz_metadata *zmd) { struct dm_zone *zone; if (list_empty(&zmd->map_seq_list)) return NULL; list_for_each_entry(zone, &zmd->map_seq_list, link) { if (!zone->bzone) continue; if (dmz_lock_zone_reclaim(zone)) return zone; } return NULL; } /* * Select a zone for reclaim. */ struct dm_zone *dmz_get_zone_for_reclaim(struct dmz_metadata *zmd) { struct dm_zone *zone; /* * Search for a zone candidate to reclaim: 2 cases are possible. * (1) There is no free sequential zones. Then a random data zone * cannot be reclaimed. So choose a sequential zone to reclaim so * that afterward a random zone can be reclaimed. * (2) At least one free sequential zone is available, then choose * the oldest random zone (data or buffer) that can be locked. */ dmz_lock_map(zmd); if (list_empty(&zmd->reserved_seq_zones_list)) zone = dmz_get_seq_zone_for_reclaim(zmd); else zone = dmz_get_rnd_zone_for_reclaim(zmd); dmz_unlock_map(zmd); return zone; } /* * Activate a zone (increment its reference count). */ void dmz_activate_zone(struct dm_zone *zone) { set_bit(DMZ_ACTIVE, &zone->flags); atomic_inc(&zone->refcount); } /* * Deactivate a zone. This decrement the zone reference counter * and clears the active state of the zone once the count reaches 0, * indicating that all BIOs to the zone have completed. Returns * true if the zone was deactivated. */ void dmz_deactivate_zone(struct dm_zone *zone) { if (atomic_dec_and_test(&zone->refcount)) { WARN_ON(!test_bit(DMZ_ACTIVE, &zone->flags)); clear_bit_unlock(DMZ_ACTIVE, &zone->flags); smp_mb__after_atomic(); } } /* * Get the zone mapping a chunk, if the chunk is mapped already. * If no mapping exist and the operation is WRITE, a zone is * allocated and used to map the chunk. * The zone returned will be set to the active state. */ struct dm_zone *dmz_get_chunk_mapping(struct dmz_metadata *zmd, unsigned int chunk, int op) { struct dmz_mblock *dmap_mblk = zmd->map_mblk[chunk >> DMZ_MAP_ENTRIES_SHIFT]; struct dmz_map *dmap = (struct dmz_map *) dmap_mblk->data; int dmap_idx = chunk & DMZ_MAP_ENTRIES_MASK; unsigned int dzone_id; struct dm_zone *dzone = NULL; int ret = 0; dmz_lock_map(zmd); again: /* Get the chunk mapping */ dzone_id = le32_to_cpu(dmap[dmap_idx].dzone_id); if (dzone_id == DMZ_MAP_UNMAPPED) { /* * Read or discard in unmapped chunks are fine. But for * writes, we need a mapping, so get one. */ if (op != REQ_OP_WRITE) goto out; /* Alloate a random zone */ dzone = dmz_alloc_zone(zmd, DMZ_ALLOC_RND); if (!dzone) { dmz_wait_for_free_zones(zmd); goto again; } dmz_map_zone(zmd, dzone, chunk); } else { /* The chunk is already mapped: get the mapping zone */ dzone = dmz_get(zmd, dzone_id); if (dzone->chunk != chunk) { dzone = ERR_PTR(-EIO); goto out; } /* Repair write pointer if the sequential dzone has error */ if (dmz_seq_write_err(dzone)) { ret = dmz_handle_seq_write_err(zmd, dzone); if (ret) { dzone = ERR_PTR(-EIO); goto out; } clear_bit(DMZ_SEQ_WRITE_ERR, &dzone->flags); } } /* * If the zone is being reclaimed, the chunk mapping may change * to a different zone. So wait for reclaim and retry. Otherwise, * activate the zone (this will prevent reclaim from touching it). */ if (dmz_in_reclaim(dzone)) { dmz_wait_for_reclaim(zmd, dzone); goto again; } dmz_activate_zone(dzone); dmz_lru_zone(zmd, dzone); out: dmz_unlock_map(zmd); return dzone; } /* * Write and discard change the block validity of data zones and their buffer * zones. Check here that valid blocks are still present. If all blocks are * invalid, the zones can be unmapped on the fly without waiting for reclaim * to do it. */ void dmz_put_chunk_mapping(struct dmz_metadata *zmd, struct dm_zone *dzone) { struct dm_zone *bzone; dmz_lock_map(zmd); bzone = dzone->bzone; if (bzone) { if (dmz_weight(bzone)) dmz_lru_zone(zmd, bzone); else { /* Empty buffer zone: reclaim it */ dmz_unmap_zone(zmd, bzone); dmz_free_zone(zmd, bzone); bzone = NULL; } } /* Deactivate the data zone */ dmz_deactivate_zone(dzone); if (dmz_is_active(dzone) || bzone || dmz_weight(dzone)) dmz_lru_zone(zmd, dzone); else { /* Unbuffered inactive empty data zone: reclaim it */ dmz_unmap_zone(zmd, dzone); dmz_free_zone(zmd, dzone); } dmz_unlock_map(zmd); } /* * Allocate and map a random zone to buffer a chunk * already mapped to a sequential zone. */ struct dm_zone *dmz_get_chunk_buffer(struct dmz_metadata *zmd, struct dm_zone *dzone) { struct dm_zone *bzone; dmz_lock_map(zmd); again: bzone = dzone->bzone; if (bzone) goto out; /* Alloate a random zone */ bzone = dmz_alloc_zone(zmd, DMZ_ALLOC_RND); if (!bzone) { dmz_wait_for_free_zones(zmd); goto again; } /* Update the chunk mapping */ dmz_set_chunk_mapping(zmd, dzone->chunk, dmz_id(zmd, dzone), dmz_id(zmd, bzone)); set_bit(DMZ_BUF, &bzone->flags); bzone->chunk = dzone->chunk; bzone->bzone = dzone; dzone->bzone = bzone; list_add_tail(&bzone->link, &zmd->map_rnd_list); out: dmz_unlock_map(zmd); return bzone; } /* * Get an unmapped (free) zone. * This must be called with the mapping lock held. */ struct dm_zone *dmz_alloc_zone(struct dmz_metadata *zmd, unsigned long flags) { struct list_head *list; struct dm_zone *zone; if (flags & DMZ_ALLOC_RND) list = &zmd->unmap_rnd_list; else list = &zmd->unmap_seq_list; again: if (list_empty(list)) { /* * No free zone: if this is for reclaim, allow using the * reserved sequential zones. */ if (!(flags & DMZ_ALLOC_RECLAIM) || list_empty(&zmd->reserved_seq_zones_list)) return NULL; zone = list_first_entry(&zmd->reserved_seq_zones_list, struct dm_zone, link); list_del_init(&zone->link); atomic_dec(&zmd->nr_reserved_seq_zones); return zone; } zone = list_first_entry(list, struct dm_zone, link); list_del_init(&zone->link); if (dmz_is_rnd(zone)) atomic_dec(&zmd->unmap_nr_rnd); else atomic_dec(&zmd->unmap_nr_seq); if (dmz_is_offline(zone)) { dmz_dev_warn(zmd->dev, "Zone %u is offline", dmz_id(zmd, zone)); zone = NULL; goto again; } return zone; } /* * Free a zone. * This must be called with the mapping lock held. */ void dmz_free_zone(struct dmz_metadata *zmd, struct dm_zone *zone) { /* If this is a sequential zone, reset it */ if (dmz_is_seq(zone)) dmz_reset_zone(zmd, zone); /* Return the zone to its type unmap list */ if (dmz_is_rnd(zone)) { list_add_tail(&zone->link, &zmd->unmap_rnd_list); atomic_inc(&zmd->unmap_nr_rnd); } else if (atomic_read(&zmd->nr_reserved_seq_zones) < zmd->nr_reserved_seq) { list_add_tail(&zone->link, &zmd->reserved_seq_zones_list); atomic_inc(&zmd->nr_reserved_seq_zones); } else { list_add_tail(&zone->link, &zmd->unmap_seq_list); atomic_inc(&zmd->unmap_nr_seq); } wake_up_all(&zmd->free_wq); } /* * Map a chunk to a zone. * This must be called with the mapping lock held. */ void dmz_map_zone(struct dmz_metadata *zmd, struct dm_zone *dzone, unsigned int chunk) { /* Set the chunk mapping */ dmz_set_chunk_mapping(zmd, chunk, dmz_id(zmd, dzone), DMZ_MAP_UNMAPPED); dzone->chunk = chunk; if (dmz_is_rnd(dzone)) list_add_tail(&dzone->link, &zmd->map_rnd_list); else list_add_tail(&dzone->link, &zmd->map_seq_list); } /* * Unmap a zone. * This must be called with the mapping lock held. */ void dmz_unmap_zone(struct dmz_metadata *zmd, struct dm_zone *zone) { unsigned int chunk = zone->chunk; unsigned int dzone_id; if (chunk == DMZ_MAP_UNMAPPED) { /* Already unmapped */ return; } if (test_and_clear_bit(DMZ_BUF, &zone->flags)) { /* * Unmapping the chunk buffer zone: clear only * the chunk buffer mapping */ dzone_id = dmz_id(zmd, zone->bzone); zone->bzone->bzone = NULL; zone->bzone = NULL; } else { /* * Unmapping the chunk data zone: the zone must * not be buffered. */ if (WARN_ON(zone->bzone)) { zone->bzone->bzone = NULL; zone->bzone = NULL; } dzone_id = DMZ_MAP_UNMAPPED; } dmz_set_chunk_mapping(zmd, chunk, dzone_id, DMZ_MAP_UNMAPPED); zone->chunk = DMZ_MAP_UNMAPPED; list_del_init(&zone->link); } /* * Set @nr_bits bits in @bitmap starting from @bit. * Return the number of bits changed from 0 to 1. */ static unsigned int dmz_set_bits(unsigned long *bitmap, unsigned int bit, unsigned int nr_bits) { unsigned long *addr; unsigned int end = bit + nr_bits; unsigned int n = 0; while (bit < end) { if (((bit & (BITS_PER_LONG - 1)) == 0) && ((end - bit) >= BITS_PER_LONG)) { /* Try to set the whole word at once */ addr = bitmap + BIT_WORD(bit); if (*addr == 0) { *addr = ULONG_MAX; n += BITS_PER_LONG; bit += BITS_PER_LONG; continue; } } if (!test_and_set_bit(bit, bitmap)) n++; bit++; } return n; } /* * Get the bitmap block storing the bit for chunk_block in zone. */ static struct dmz_mblock *dmz_get_bitmap(struct dmz_metadata *zmd, struct dm_zone *zone, sector_t chunk_block) { sector_t bitmap_block = 1 + zmd->nr_map_blocks + (sector_t)(dmz_id(zmd, zone) * zmd->zone_nr_bitmap_blocks) + (chunk_block >> DMZ_BLOCK_SHIFT_BITS); return dmz_get_mblock(zmd, bitmap_block); } /* * Copy the valid blocks bitmap of from_zone to the bitmap of to_zone. */ int dmz_copy_valid_blocks(struct dmz_metadata *zmd, struct dm_zone *from_zone, struct dm_zone *to_zone) { struct dmz_mblock *from_mblk, *to_mblk; sector_t chunk_block = 0; /* Get the zones bitmap blocks */ while (chunk_block < zmd->dev->zone_nr_blocks) { from_mblk = dmz_get_bitmap(zmd, from_zone, chunk_block); if (IS_ERR(from_mblk)) return PTR_ERR(from_mblk); to_mblk = dmz_get_bitmap(zmd, to_zone, chunk_block); if (IS_ERR(to_mblk)) { dmz_release_mblock(zmd, from_mblk); return PTR_ERR(to_mblk); } memcpy(to_mblk->data, from_mblk->data, DMZ_BLOCK_SIZE); dmz_dirty_mblock(zmd, to_mblk); dmz_release_mblock(zmd, to_mblk); dmz_release_mblock(zmd, from_mblk); chunk_block += DMZ_BLOCK_SIZE_BITS; } to_zone->weight = from_zone->weight; return 0; } /* * Merge the valid blocks bitmap of from_zone into the bitmap of to_zone, * starting from chunk_block. */ int dmz_merge_valid_blocks(struct dmz_metadata *zmd, struct dm_zone *from_zone, struct dm_zone *to_zone, sector_t chunk_block) { unsigned int nr_blocks; int ret; /* Get the zones bitmap blocks */ while (chunk_block < zmd->dev->zone_nr_blocks) { /* Get a valid region from the source zone */ ret = dmz_first_valid_block(zmd, from_zone, &chunk_block); if (ret <= 0) return ret; nr_blocks = ret; ret = dmz_validate_blocks(zmd, to_zone, chunk_block, nr_blocks); if (ret) return ret; chunk_block += nr_blocks; } return 0; } /* * Validate all the blocks in the range [block..block+nr_blocks-1]. */ int dmz_validate_blocks(struct dmz_metadata *zmd, struct dm_zone *zone, sector_t chunk_block, unsigned int nr_blocks) { unsigned int count, bit, nr_bits; unsigned int zone_nr_blocks = zmd->dev->zone_nr_blocks; struct dmz_mblock *mblk; unsigned int n = 0; dmz_dev_debug(zmd->dev, "=> VALIDATE zone %u, block %llu, %u blocks", dmz_id(zmd, zone), (unsigned long long)chunk_block, nr_blocks); WARN_ON(chunk_block + nr_blocks > zone_nr_blocks); while (nr_blocks) { /* Get bitmap block */ mblk = dmz_get_bitmap(zmd, zone, chunk_block); if (IS_ERR(mblk)) return PTR_ERR(mblk); /* Set bits */ bit = chunk_block & DMZ_BLOCK_MASK_BITS; nr_bits = min(nr_blocks, DMZ_BLOCK_SIZE_BITS - bit); count = dmz_set_bits((unsigned long *)mblk->data, bit, nr_bits); if (count) { dmz_dirty_mblock(zmd, mblk); n += count; } dmz_release_mblock(zmd, mblk); nr_blocks -= nr_bits; chunk_block += nr_bits; } if (likely(zone->weight + n <= zone_nr_blocks)) zone->weight += n; else { dmz_dev_warn(zmd->dev, "Zone %u: weight %u should be <= %u", dmz_id(zmd, zone), zone->weight, zone_nr_blocks - n); zone->weight = zone_nr_blocks; } return 0; } /* * Clear nr_bits bits in bitmap starting from bit. * Return the number of bits cleared. */ static int dmz_clear_bits(unsigned long *bitmap, int bit, int nr_bits) { unsigned long *addr; int end = bit + nr_bits; int n = 0; while (bit < end) { if (((bit & (BITS_PER_LONG - 1)) == 0) && ((end - bit) >= BITS_PER_LONG)) { /* Try to clear whole word at once */ addr = bitmap + BIT_WORD(bit); if (*addr == ULONG_MAX) { *addr = 0; n += BITS_PER_LONG; bit += BITS_PER_LONG; continue; } } if (test_and_clear_bit(bit, bitmap)) n++; bit++; } return n; } /* * Invalidate all the blocks in the range [block..block+nr_blocks-1]. */ int dmz_invalidate_blocks(struct dmz_metadata *zmd, struct dm_zone *zone, sector_t chunk_block, unsigned int nr_blocks) { unsigned int count, bit, nr_bits; struct dmz_mblock *mblk; unsigned int n = 0; dmz_dev_debug(zmd->dev, "=> INVALIDATE zone %u, block %llu, %u blocks", dmz_id(zmd, zone), (u64)chunk_block, nr_blocks); WARN_ON(chunk_block + nr_blocks > zmd->dev->zone_nr_blocks); while (nr_blocks) { /* Get bitmap block */ mblk = dmz_get_bitmap(zmd, zone, chunk_block); if (IS_ERR(mblk)) return PTR_ERR(mblk); /* Clear bits */ bit = chunk_block & DMZ_BLOCK_MASK_BITS; nr_bits = min(nr_blocks, DMZ_BLOCK_SIZE_BITS - bit); count = dmz_clear_bits((unsigned long *)mblk->data, bit, nr_bits); if (count) { dmz_dirty_mblock(zmd, mblk); n += count; } dmz_release_mblock(zmd, mblk); nr_blocks -= nr_bits; chunk_block += nr_bits; } if (zone->weight >= n) zone->weight -= n; else { dmz_dev_warn(zmd->dev, "Zone %u: weight %u should be >= %u", dmz_id(zmd, zone), zone->weight, n); zone->weight = 0; } return 0; } /* * Get a block bit value. */ static int dmz_test_block(struct dmz_metadata *zmd, struct dm_zone *zone, sector_t chunk_block) { struct dmz_mblock *mblk; int ret; WARN_ON(chunk_block >= zmd->dev->zone_nr_blocks); /* Get bitmap block */ mblk = dmz_get_bitmap(zmd, zone, chunk_block); if (IS_ERR(mblk)) return PTR_ERR(mblk); /* Get offset */ ret = test_bit(chunk_block & DMZ_BLOCK_MASK_BITS, (unsigned long *) mblk->data) != 0; dmz_release_mblock(zmd, mblk); return ret; } /* * Return the number of blocks from chunk_block to the first block with a bit * value specified by set. Search at most nr_blocks blocks from chunk_block. */ static int dmz_to_next_set_block(struct dmz_metadata *zmd, struct dm_zone *zone, sector_t chunk_block, unsigned int nr_blocks, int set) { struct dmz_mblock *mblk; unsigned int bit, set_bit, nr_bits; unsigned long *bitmap; int n = 0; WARN_ON(chunk_block + nr_blocks > zmd->dev->zone_nr_blocks); while (nr_blocks) { /* Get bitmap block */ mblk = dmz_get_bitmap(zmd, zone, chunk_block); if (IS_ERR(mblk)) return PTR_ERR(mblk); /* Get offset */ bitmap = (unsigned long *) mblk->data; bit = chunk_block & DMZ_BLOCK_MASK_BITS; nr_bits = min(nr_blocks, DMZ_BLOCK_SIZE_BITS - bit); if (set) set_bit = find_next_bit(bitmap, DMZ_BLOCK_SIZE_BITS, bit); else set_bit = find_next_zero_bit(bitmap, DMZ_BLOCK_SIZE_BITS, bit); dmz_release_mblock(zmd, mblk); n += set_bit - bit; if (set_bit < DMZ_BLOCK_SIZE_BITS) break; nr_blocks -= nr_bits; chunk_block += nr_bits; } return n; } /* * Test if chunk_block is valid. If it is, the number of consecutive * valid blocks from chunk_block will be returned. */ int dmz_block_valid(struct dmz_metadata *zmd, struct dm_zone *zone, sector_t chunk_block) { int valid; valid = dmz_test_block(zmd, zone, chunk_block); if (valid <= 0) return valid; /* The block is valid: get the number of valid blocks from block */ return dmz_to_next_set_block(zmd, zone, chunk_block, zmd->dev->zone_nr_blocks - chunk_block, 0); } /* * Find the first valid block from @chunk_block in @zone. * If such a block is found, its number is returned using * @chunk_block and the total number of valid blocks from @chunk_block * is returned. */ int dmz_first_valid_block(struct dmz_metadata *zmd, struct dm_zone *zone, sector_t *chunk_block) { sector_t start_block = *chunk_block; int ret; ret = dmz_to_next_set_block(zmd, zone, start_block, zmd->dev->zone_nr_blocks - start_block, 1); if (ret < 0) return ret; start_block += ret; *chunk_block = start_block; return dmz_to_next_set_block(zmd, zone, start_block, zmd->dev->zone_nr_blocks - start_block, 0); } /* * Count the number of bits set starting from bit up to bit + nr_bits - 1. */ static int dmz_count_bits(void *bitmap, int bit, int nr_bits) { unsigned long *addr; int end = bit + nr_bits; int n = 0; while (bit < end) { if (((bit & (BITS_PER_LONG - 1)) == 0) && ((end - bit) >= BITS_PER_LONG)) { addr = (unsigned long *)bitmap + BIT_WORD(bit); if (*addr == ULONG_MAX) { n += BITS_PER_LONG; bit += BITS_PER_LONG; continue; } } if (test_bit(bit, bitmap)) n++; bit++; } return n; } /* * Get a zone weight. */ static void dmz_get_zone_weight(struct dmz_metadata *zmd, struct dm_zone *zone) { struct dmz_mblock *mblk; sector_t chunk_block = 0; unsigned int bit, nr_bits; unsigned int nr_blocks = zmd->dev->zone_nr_blocks; void *bitmap; int n = 0; while (nr_blocks) { /* Get bitmap block */ mblk = dmz_get_bitmap(zmd, zone, chunk_block); if (IS_ERR(mblk)) { n = 0; break; } /* Count bits in this block */ bitmap = mblk->data; bit = chunk_block & DMZ_BLOCK_MASK_BITS; nr_bits = min(nr_blocks, DMZ_BLOCK_SIZE_BITS - bit); n += dmz_count_bits(bitmap, bit, nr_bits); dmz_release_mblock(zmd, mblk); nr_blocks -= nr_bits; chunk_block += nr_bits; } zone->weight = n; } /* * Cleanup the zoned metadata resources. */ static void dmz_cleanup_metadata(struct dmz_metadata *zmd) { struct rb_root *root; struct dmz_mblock *mblk, *next; int i; /* Release zone mapping resources */ if (zmd->map_mblk) { for (i = 0; i < zmd->nr_map_blocks; i++) dmz_release_mblock(zmd, zmd->map_mblk[i]); kfree(zmd->map_mblk); zmd->map_mblk = NULL; } /* Release super blocks */ for (i = 0; i < 2; i++) { if (zmd->sb[i].mblk) { dmz_free_mblock(zmd, zmd->sb[i].mblk); zmd->sb[i].mblk = NULL; } } /* Free cached blocks */ while (!list_empty(&zmd->mblk_dirty_list)) { mblk = list_first_entry(&zmd->mblk_dirty_list, struct dmz_mblock, link); dmz_dev_warn(zmd->dev, "mblock %llu still in dirty list (ref %u)", (u64)mblk->no, mblk->ref); list_del_init(&mblk->link); rb_erase(&mblk->node, &zmd->mblk_rbtree); dmz_free_mblock(zmd, mblk); } while (!list_empty(&zmd->mblk_lru_list)) { mblk = list_first_entry(&zmd->mblk_lru_list, struct dmz_mblock, link); list_del_init(&mblk->link); rb_erase(&mblk->node, &zmd->mblk_rbtree); dmz_free_mblock(zmd, mblk); } /* Sanity checks: the mblock rbtree should now be empty */ root = &zmd->mblk_rbtree; rbtree_postorder_for_each_entry_safe(mblk, next, root, node) { dmz_dev_warn(zmd->dev, "mblock %llu ref %u still in rbtree", (u64)mblk->no, mblk->ref); mblk->ref = 0; dmz_free_mblock(zmd, mblk); } /* Free the zone descriptors */ dmz_drop_zones(zmd); mutex_destroy(&zmd->mblk_flush_lock); mutex_destroy(&zmd->map_lock); } /* * Initialize the zoned metadata. */ int dmz_ctr_metadata(struct dmz_dev *dev, struct dmz_metadata **metadata) { struct dmz_metadata *zmd; unsigned int i, zid; struct dm_zone *zone; int ret; zmd = kzalloc(sizeof(struct dmz_metadata), GFP_KERNEL); if (!zmd) return -ENOMEM; zmd->dev = dev; zmd->mblk_rbtree = RB_ROOT; init_rwsem(&zmd->mblk_sem); mutex_init(&zmd->mblk_flush_lock); spin_lock_init(&zmd->mblk_lock); INIT_LIST_HEAD(&zmd->mblk_lru_list); INIT_LIST_HEAD(&zmd->mblk_dirty_list); mutex_init(&zmd->map_lock); atomic_set(&zmd->unmap_nr_rnd, 0); INIT_LIST_HEAD(&zmd->unmap_rnd_list); INIT_LIST_HEAD(&zmd->map_rnd_list); atomic_set(&zmd->unmap_nr_seq, 0); INIT_LIST_HEAD(&zmd->unmap_seq_list); INIT_LIST_HEAD(&zmd->map_seq_list); atomic_set(&zmd->nr_reserved_seq_zones, 0); INIT_LIST_HEAD(&zmd->reserved_seq_zones_list); init_waitqueue_head(&zmd->free_wq); /* Initialize zone descriptors */ ret = dmz_init_zones(zmd); if (ret) goto err; /* Get super block */ ret = dmz_load_sb(zmd); if (ret) goto err; /* Set metadata zones starting from sb_zone */ zid = dmz_id(zmd, zmd->sb_zone); for (i = 0; i < zmd->nr_meta_zones << 1; i++) { zone = dmz_get(zmd, zid + i); if (!dmz_is_rnd(zone)) goto err; set_bit(DMZ_META, &zone->flags); } /* Load mapping table */ ret = dmz_load_mapping(zmd); if (ret) goto err; /* * Cache size boundaries: allow at least 2 super blocks, the chunk map * blocks and enough blocks to be able to cache the bitmap blocks of * up to 16 zones when idle (min_nr_mblks). Otherwise, if busy, allow * the cache to add 512 more metadata blocks. */ zmd->min_nr_mblks = 2 + zmd->nr_map_blocks + zmd->zone_nr_bitmap_blocks * 16; zmd->max_nr_mblks = zmd->min_nr_mblks + 512; zmd->mblk_shrinker.count_objects = dmz_mblock_shrinker_count; zmd->mblk_shrinker.scan_objects = dmz_mblock_shrinker_scan; zmd->mblk_shrinker.seeks = DEFAULT_SEEKS; /* Metadata cache shrinker */ ret = register_shrinker(&zmd->mblk_shrinker); if (ret) { dmz_dev_err(dev, "Register metadata cache shrinker failed"); goto err; } dmz_dev_info(dev, "Host-%s zoned block device", bdev_zoned_model(dev->bdev) == BLK_ZONED_HA ? "aware" : "managed"); dmz_dev_info(dev, " %llu 512-byte logical sectors", (u64)dev->capacity); dmz_dev_info(dev, " %u zones of %llu 512-byte logical sectors", dev->nr_zones, (u64)dev->zone_nr_sectors); dmz_dev_info(dev, " %u metadata zones", zmd->nr_meta_zones * 2); dmz_dev_info(dev, " %u data zones for %u chunks", zmd->nr_data_zones, zmd->nr_chunks); dmz_dev_info(dev, " %u random zones (%u unmapped)", zmd->nr_rnd, atomic_read(&zmd->unmap_nr_rnd)); dmz_dev_info(dev, " %u sequential zones (%u unmapped)", zmd->nr_seq, atomic_read(&zmd->unmap_nr_seq)); dmz_dev_info(dev, " %u reserved sequential data zones", zmd->nr_reserved_seq); dmz_dev_debug(dev, "Format:"); dmz_dev_debug(dev, "%u metadata blocks per set (%u max cache)", zmd->nr_meta_blocks, zmd->max_nr_mblks); dmz_dev_debug(dev, " %u data zone mapping blocks", zmd->nr_map_blocks); dmz_dev_debug(dev, " %u bitmap blocks", zmd->nr_bitmap_blocks); *metadata = zmd; return 0; err: dmz_cleanup_metadata(zmd); kfree(zmd); *metadata = NULL; return ret; } /* * Cleanup the zoned metadata resources. */ void dmz_dtr_metadata(struct dmz_metadata *zmd) { unregister_shrinker(&zmd->mblk_shrinker); dmz_cleanup_metadata(zmd); kfree(zmd); } /* * Check zone information on resume. */ int dmz_resume_metadata(struct dmz_metadata *zmd) { struct dmz_dev *dev = zmd->dev; struct dm_zone *zone; sector_t wp_block; unsigned int i; int ret; /* Check zones */ for (i = 0; i < dev->nr_zones; i++) { zone = dmz_get(zmd, i); if (!zone) { dmz_dev_err(dev, "Unable to get zone %u", i); return -EIO; } wp_block = zone->wp_block; ret = dmz_update_zone(zmd, zone); if (ret) { dmz_dev_err(dev, "Broken zone %u", i); return ret; } if (dmz_is_offline(zone)) { dmz_dev_warn(dev, "Zone %u is offline", i); continue; } /* Check write pointer */ if (!dmz_is_seq(zone)) zone->wp_block = 0; else if (zone->wp_block != wp_block) { dmz_dev_err(dev, "Zone %u: Invalid wp (%llu / %llu)", i, (u64)zone->wp_block, (u64)wp_block); zone->wp_block = wp_block; dmz_invalidate_blocks(zmd, zone, zone->wp_block, dev->zone_nr_blocks - zone->wp_block); } } return 0; }