| /* |
| * Copyright (C) 2017 Western Digital Corporation or its affiliates. |
| * |
| * This file is released under the GPL. |
| */ |
| |
| #include "dm-zoned.h" |
| |
| #include <linux/module.h> |
| #include <linux/crc32.h> |
| |
| #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 zone_bits_per_mblk; |
| |
| 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; |
| |
| if (dmz_bdev_is_dying(zmd->dev)) |
| return ERR_PTR(-EIO); |
| |
| /* Get a new block and a BIO to read it */ |
| mblk = dmz_alloc_mblock(zmd, mblk_no); |
| if (!mblk) |
| return ERR_PTR(-ENOMEM); |
| |
| bio = bio_alloc(GFP_NOIO, 1); |
| if (!bio) { |
| dmz_free_mblock(zmd, mblk); |
| return ERR_PTR(-ENOMEM); |
| } |
| |
| 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 (IS_ERR(mblk)) |
| return mblk; |
| } |
| |
| /* 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); |
| dmz_check_bdev(zmd->dev); |
| 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 int 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; |
| |
| if (dmz_bdev_is_dying(zmd->dev)) |
| return -EIO; |
| |
| bio = bio_alloc(GFP_NOIO, 1); |
| if (!bio) { |
| set_bit(DMZ_META_ERROR, &mblk->state); |
| return -ENOMEM; |
| } |
| |
| 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); |
| |
| return 0; |
| } |
| |
| /* |
| * 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; |
| |
| if (dmz_bdev_is_dying(zmd->dev)) |
| return -EIO; |
| |
| 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); |
| |
| if (ret) |
| dmz_check_bdev(zmd->dev); |
| 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, nr_mblks_submitted = 0; |
| |
| /* Issue writes */ |
| blk_start_plug(&plug); |
| list_for_each_entry(mblk, write_list, link) { |
| ret = dmz_write_mblock(zmd, mblk, set); |
| if (ret) |
| break; |
| nr_mblks_submitted++; |
| } |
| blk_finish_plug(&plug); |
| |
| /* Wait for completion */ |
| list_for_each_entry(mblk, write_list, link) { |
| if (!nr_mblks_submitted) |
| break; |
| 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); |
| dmz_check_bdev(zmd->dev); |
| ret = -EIO; |
| } |
| nr_mblks_submitted--; |
| } |
| |
| /* 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); |
| |
| if (dmz_bdev_is_dying(zmd->dev)) { |
| ret = -EIO; |
| goto out; |
| } |
| |
| /* 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 err; |
| } |
| |
| /* |
| * 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 err; |
| |
| /* |
| * 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 err; |
| |
| ret = dmz_write_sb(zmd, zmd->mblk_primary); |
| if (ret) |
| goto err; |
| |
| 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: |
| dmz_unlock_flush(zmd); |
| up_write(&zmd->mblk_sem); |
| |
| return ret; |
| |
| err: |
| if (!list_empty(&write_list)) { |
| spin_lock(&zmd->mblk_lock); |
| list_splice(&write_list, &zmd->mblk_dirty_list); |
| spin_unlock(&zmd->mblk_lock); |
| } |
| if (!dmz_check_bdev(zmd->dev)) |
| ret = -EIO; |
| goto out; |
| } |
| |
| /* |
| * 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 = |
| max_t(sector_t, 1, zmd->zone_bitmap_size >> DMZ_BLOCK_SHIFT); |
| zmd->zone_bits_per_mblk = min_t(sector_t, dev->zone_nr_blocks, |
| DMZ_BLOCK_SIZE_BITS); |
| |
| /* 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)); |
| dmz_check_bdev(zmd->dev); |
| 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 ERR_PTR(-EBUSY); |
| |
| 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 ERR_PTR(-EBUSY); |
| } |
| |
| /* |
| * 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 ERR_PTR(-EBUSY); |
| |
| list_for_each_entry(zone, &zmd->map_seq_list, link) { |
| if (!zone->bzone) |
| continue; |
| if (dmz_lock_zone_reclaim(zone)) |
| return zone; |
| } |
| |
| return ERR_PTR(-EBUSY); |
| } |
| |
| /* |
| * 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; |
| } |
| |
| /* |
| * 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) { |
| if (dmz_bdev_is_dying(zmd->dev)) { |
| dzone = ERR_PTR(-EIO); |
| goto out; |
| } |
| 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) { |
| if (dmz_bdev_is_dying(zmd->dev)) { |
| bzone = ERR_PTR(-EIO); |
| goto out; |
| } |
| 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 += zmd->zone_bits_per_mblk; |
| } |
| |
| 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, zmd->zone_bits_per_mblk - 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, zmd->zone_bits_per_mblk - 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 int zone_bits = zmd->zone_bits_per_mblk; |
| 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, zone_bits - bit); |
| if (set) |
| set_bit = find_next_bit(bitmap, zone_bits, bit); |
| else |
| set_bit = find_next_zero_bit(bitmap, zone_bits, bit); |
| dmz_release_mblock(zmd, mblk); |
| |
| n += set_bit - bit; |
| if (set_bit < zone_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, zmd->zone_bits_per_mblk - 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; |
| } |