diff options
Diffstat (limited to 'drivers/md/dm-zoned-metadata.c')
| -rw-r--r-- | drivers/md/dm-zoned-metadata.c | 3061 |
1 files changed, 3061 insertions, 0 deletions
diff --git a/drivers/md/dm-zoned-metadata.c b/drivers/md/dm-zoned-metadata.c new file mode 100644 index 000000000..510090797 --- /dev/null +++ b/drivers/md/dm-zoned-metadata.c @@ -0,0 +1,3061 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * 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> +#include <linux/sched/mm.h> + +#define DM_MSG_PREFIX "zoned metadata" + +/* + * Metadata version. + */ +#define DMZ_META_VER 2 + +/* + * 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 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 */ + + /* DM-Zoned label */ + u8 dmz_label[32]; /* 80 */ + + /* DM-Zoned UUID */ + u8 dmz_uuid[16]; /* 96 */ + + /* Device UUID */ + u8 dev_uuid[16]; /* 112 */ + + /* Padding to full 512B sector */ + u8 reserved[400]; /* 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_dev *dev; + struct dmz_mblock *mblk; + struct dmz_super *sb; + struct dm_zone *zone; +}; + +/* + * In-memory metadata. + */ +struct dmz_metadata { + struct dmz_dev *dev; + unsigned int nr_devs; + + char devname[BDEVNAME_SIZE]; + char label[BDEVNAME_SIZE]; + uuid_t uuid; + + sector_t zone_bitmap_size; + unsigned int zone_nr_bitmap_blocks; + unsigned int zone_bits_per_mblk; + + sector_t zone_nr_blocks; + sector_t zone_nr_blocks_shift; + + sector_t zone_nr_sectors; + sector_t zone_nr_sectors_shift; + + unsigned int nr_bitmap_blocks; + unsigned int nr_map_blocks; + + unsigned int nr_zones; + unsigned int nr_useable_zones; + unsigned int nr_meta_blocks; + unsigned int nr_meta_zones; + unsigned int nr_data_zones; + unsigned int nr_cache_zones; + unsigned int nr_rnd_zones; + unsigned int nr_reserved_seq; + unsigned int nr_chunks; + + /* Zone information array */ + struct xarray zones; + + struct dmz_sb sb[2]; + unsigned int mblk_primary; + unsigned int sb_version; + 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_cache; + atomic_t unmap_nr_cache; + struct list_head unmap_cache_list; + struct list_head map_cache_list; + + atomic_t nr_reserved_seq_zones; + struct list_head reserved_seq_zones_list; + + wait_queue_head_t free_wq; +}; + +#define dmz_zmd_info(zmd, format, args...) \ + DMINFO("(%s): " format, (zmd)->label, ## args) + +#define dmz_zmd_err(zmd, format, args...) \ + DMERR("(%s): " format, (zmd)->label, ## args) + +#define dmz_zmd_warn(zmd, format, args...) \ + DMWARN("(%s): " format, (zmd)->label, ## args) + +#define dmz_zmd_debug(zmd, format, args...) \ + DMDEBUG("(%s): " format, (zmd)->label, ## args) +/* + * Various accessors + */ +static unsigned int dmz_dev_zone_id(struct dmz_metadata *zmd, struct dm_zone *zone) +{ + if (WARN_ON(!zone)) + return 0; + + return zone->id - zone->dev->zone_offset; +} + +sector_t dmz_start_sect(struct dmz_metadata *zmd, struct dm_zone *zone) +{ + unsigned int zone_id = dmz_dev_zone_id(zmd, zone); + + return (sector_t)zone_id << zmd->zone_nr_sectors_shift; +} + +sector_t dmz_start_block(struct dmz_metadata *zmd, struct dm_zone *zone) +{ + unsigned int zone_id = dmz_dev_zone_id(zmd, zone); + + return (sector_t)zone_id << zmd->zone_nr_blocks_shift; +} + +unsigned int dmz_zone_nr_blocks(struct dmz_metadata *zmd) +{ + return zmd->zone_nr_blocks; +} + +unsigned int dmz_zone_nr_blocks_shift(struct dmz_metadata *zmd) +{ + return zmd->zone_nr_blocks_shift; +} + +unsigned int dmz_zone_nr_sectors(struct dmz_metadata *zmd) +{ + return zmd->zone_nr_sectors; +} + +unsigned int dmz_zone_nr_sectors_shift(struct dmz_metadata *zmd) +{ + return zmd->zone_nr_sectors_shift; +} + +unsigned int dmz_nr_zones(struct dmz_metadata *zmd) +{ + return zmd->nr_zones; +} + +unsigned int dmz_nr_chunks(struct dmz_metadata *zmd) +{ + return zmd->nr_chunks; +} + +unsigned int dmz_nr_rnd_zones(struct dmz_metadata *zmd, int idx) +{ + return zmd->dev[idx].nr_rnd; +} + +unsigned int dmz_nr_unmap_rnd_zones(struct dmz_metadata *zmd, int idx) +{ + return atomic_read(&zmd->dev[idx].unmap_nr_rnd); +} + +unsigned int dmz_nr_cache_zones(struct dmz_metadata *zmd) +{ + return zmd->nr_cache; +} + +unsigned int dmz_nr_unmap_cache_zones(struct dmz_metadata *zmd) +{ + return atomic_read(&zmd->unmap_nr_cache); +} + +unsigned int dmz_nr_seq_zones(struct dmz_metadata *zmd, int idx) +{ + return zmd->dev[idx].nr_seq; +} + +unsigned int dmz_nr_unmap_seq_zones(struct dmz_metadata *zmd, int idx) +{ + return atomic_read(&zmd->dev[idx].unmap_nr_seq); +} + +static struct dm_zone *dmz_get(struct dmz_metadata *zmd, unsigned int zone_id) +{ + return xa_load(&zmd->zones, zone_id); +} + +static struct dm_zone *dmz_insert(struct dmz_metadata *zmd, + unsigned int zone_id, struct dmz_dev *dev) +{ + struct dm_zone *zone = kzalloc(sizeof(struct dm_zone), GFP_KERNEL); + + if (!zone) + return ERR_PTR(-ENOMEM); + + if (xa_insert(&zmd->zones, zone_id, zone, GFP_KERNEL)) { + kfree(zone); + return ERR_PTR(-EBUSY); + } + + INIT_LIST_HEAD(&zone->link); + atomic_set(&zone->refcount, 0); + zone->id = zone_id; + zone->chunk = DMZ_MAP_UNMAPPED; + zone->dev = dev; + + return zone; +} + +const char *dmz_metadata_label(struct dmz_metadata *zmd) +{ + return (const char *)zmd->label; +} + +bool dmz_check_dev(struct dmz_metadata *zmd) +{ + unsigned int i; + + for (i = 0; i < zmd->nr_devs; i++) { + if (!dmz_check_bdev(&zmd->dev[i])) + return false; + } + return true; +} + +bool dmz_dev_is_dying(struct dmz_metadata *zmd) +{ + unsigned int i; + + for (i = 0; i < zmd->nr_devs; i++) { + if (dmz_bdev_is_dying(&zmd->dev[i])) + return true; + } + return false; +} + +/* + * 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 state 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 dmz_dev *dev = zmd->sb[zmd->mblk_primary].dev; + struct bio *bio; + + if (dmz_bdev_is_dying(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, 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; + struct dmz_dev *dev = zmd->sb[zmd->mblk_primary].dev; + + /* 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(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) +{ + struct dmz_dev *dev = zmd->sb[set].dev; + sector_t block = zmd->sb[set].block + mblk->no; + struct bio *bio; + + if (dmz_bdev_is_dying(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, 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_dev *dev, int op, + sector_t block, struct page *page) +{ + struct bio *bio; + int ret; + + if (WARN_ON(!dev)) + return -EIO; + + if (dmz_bdev_is_dying(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, 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(dev); + return ret; +} + +/* + * Write super block of the specified metadata set. + */ +static int dmz_write_sb(struct dmz_metadata *zmd, unsigned int set) +{ + struct dmz_mblock *mblk = zmd->sb[set].mblk; + struct dmz_super *sb = zmd->sb[set].sb; + struct dmz_dev *dev = zmd->sb[set].dev; + sector_t sb_block; + u64 sb_gen = zmd->sb_gen + 1; + int ret; + + sb->magic = cpu_to_le32(DMZ_MAGIC); + + sb->version = cpu_to_le32(zmd->sb_version); + if (zmd->sb_version > 1) { + BUILD_BUG_ON(UUID_SIZE != 16); + export_uuid(sb->dmz_uuid, &zmd->uuid); + memcpy(sb->dmz_label, zmd->label, BDEVNAME_SIZE); + export_uuid(sb->dev_uuid, &dev->uuid); + } + + sb->gen = cpu_to_le64(sb_gen); + + /* + * The metadata always references the absolute block address, + * ie relative to the entire block range, not the per-device + * block address. + */ + sb_block = zmd->sb[set].zone->id << zmd->zone_nr_blocks_shift; + sb->sb_block = cpu_to_le64(sb_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(dev, REQ_OP_WRITE, zmd->sb[set].block, + mblk->page); + if (ret == 0) + ret = blkdev_issue_flush(dev->bdev, GFP_NOIO); + + 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 dmz_dev *dev = zmd->sb[set].dev; + 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(dev); + ret = -EIO; + } + nr_mblks_submitted--; + } + + /* Flush drive cache (this will also sync data) */ + if (ret == 0) + ret = blkdev_issue_flush(dev->bdev, GFP_NOIO); + + 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; + struct dmz_dev *dev; + 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); + dev = zmd->sb[zmd->mblk_primary].dev; + + /* + * 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(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(dev->bdev, GFP_NOIO); + 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(dev)) + ret = -EIO; + goto out; +} + +/* + * Check super block. + */ +static int dmz_check_sb(struct dmz_metadata *zmd, struct dmz_sb *dsb, + bool tertiary) +{ + struct dmz_super *sb = dsb->sb; + struct dmz_dev *dev = dsb->dev; + unsigned int nr_meta_zones, nr_data_zones; + u32 crc, stored_crc; + u64 gen, sb_block; + + 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; + } + + zmd->sb_version = le32_to_cpu(sb->version); + if (zmd->sb_version > DMZ_META_VER) { + dmz_dev_err(dev, "Invalid meta version (needed %d, got %d)", + DMZ_META_VER, zmd->sb_version); + return -EINVAL; + } + if (zmd->sb_version < 2 && tertiary) { + dmz_dev_err(dev, "Tertiary superblocks are not supported"); + return -EINVAL; + } + + 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; + } + + sb_block = le64_to_cpu(sb->sb_block); + if (sb_block != (u64)dsb->zone->id << zmd->zone_nr_blocks_shift ) { + dmz_dev_err(dev, "Invalid superblock position " + "(is %llu expected %llu)", + sb_block, + (u64)dsb->zone->id << zmd->zone_nr_blocks_shift); + return -EINVAL; + } + if (zmd->sb_version > 1) { + uuid_t sb_uuid; + + import_uuid(&sb_uuid, sb->dmz_uuid); + if (uuid_is_null(&sb_uuid)) { + dmz_dev_err(dev, "NULL DM-Zoned uuid"); + return -ENXIO; + } else if (uuid_is_null(&zmd->uuid)) { + uuid_copy(&zmd->uuid, &sb_uuid); + } else if (!uuid_equal(&zmd->uuid, &sb_uuid)) { + dmz_dev_err(dev, "mismatching DM-Zoned uuid, " + "is %pUl expected %pUl", + &sb_uuid, &zmd->uuid); + return -ENXIO; + } + if (!strlen(zmd->label)) + memcpy(zmd->label, sb->dmz_label, BDEVNAME_SIZE); + else if (memcmp(zmd->label, sb->dmz_label, BDEVNAME_SIZE)) { + dmz_dev_err(dev, "mismatching DM-Zoned label, " + "is %s expected %s", + sb->dmz_label, zmd->label); + return -ENXIO; + } + import_uuid(&dev->uuid, sb->dev_uuid); + if (uuid_is_null(&dev->uuid)) { + dmz_dev_err(dev, "NULL device uuid"); + return -ENXIO; + } + + if (tertiary) { + /* + * Generation number should be 0, but it doesn't + * really matter if it isn't. + */ + if (gen != 0) + dmz_dev_warn(dev, "Invalid generation %llu", + gen); + return 0; + } + } + + nr_meta_zones = (le32_to_cpu(sb->nr_meta_blocks) + zmd->zone_nr_blocks - 1) + >> zmd->zone_nr_blocks_shift; + if (!nr_meta_zones || + (zmd->nr_devs <= 1 && nr_meta_zones >= zmd->nr_rnd_zones) || + (zmd->nr_devs > 1 && nr_meta_zones >= zmd->nr_cache_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, struct dmz_sb *sb, int set) +{ + dmz_zmd_debug(zmd, "read superblock set %d dev %s block %llu", + set, sb->dev->name, sb->block); + + return dmz_rdwr_block(sb->dev, REQ_OP_READ, + sb->block, sb->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->zone_nr_blocks; + struct dmz_mblock *mblk; + unsigned int zone_id = zmd->sb[0].zone->id; + 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; + zmd->sb[1].zone = dmz_get(zmd, zone_id + 1); + zmd->sb[1].dev = zmd->sb[0].dev; + for (i = 1; i < zmd->nr_rnd_zones; i++) { + if (dmz_read_sb(zmd, &zmd->sb[1], 1) != 0) + break; + if (le32_to_cpu(zmd->sb[1].sb->magic) == DMZ_MAGIC) + return 0; + zmd->sb[1].block += zone_nr_blocks; + zmd->sb[1].zone = dmz_get(zmd, zone_id + i); + } + + dmz_free_mblock(zmd, mblk); + zmd->sb[1].mblk = NULL; + zmd->sb[1].zone = NULL; + zmd->sb[1].dev = NULL; + + return -EIO; +} + +/* + * Read a super block from disk. + */ +static int dmz_get_sb(struct dmz_metadata *zmd, struct dmz_sb *sb, int set) +{ + struct dmz_mblock *mblk; + int ret; + + /* Allocate a block */ + mblk = dmz_alloc_mblock(zmd, 0); + if (!mblk) + return -ENOMEM; + + sb->mblk = mblk; + sb->sb = mblk->data; + + /* Read super block */ + ret = dmz_read_sb(zmd, sb, set); + if (ret) { + dmz_free_mblock(zmd, mblk); + sb->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->sb[dst_set].dev, + "Metadata set %u invalid: recovering", dst_set); + + if (dst_set == 0) + zmd->sb[0].block = dmz_start_block(zmd, zmd->sb[0].zone); + else + zmd->sb[1].block = dmz_start_block(zmd, zmd->sb[1].zone); + + 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->sb[src_set].dev, REQ_OP_READ, + zmd->sb[src_set].block + i, page); + if (ret) + goto out; + ret = dmz_rdwr_block(zmd->sb[dst_set].dev, 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; + + if (!zmd->sb[0].zone) { + dmz_zmd_err(zmd, "Primary super block zone not set"); + return -ENXIO; + } + + /* Read and check the primary super block */ + zmd->sb[0].block = dmz_start_block(zmd, zmd->sb[0].zone); + zmd->sb[0].dev = zmd->sb[0].zone->dev; + ret = dmz_get_sb(zmd, &zmd->sb[0], 0); + if (ret) { + dmz_dev_err(zmd->sb[0].dev, "Read primary super block failed"); + return ret; + } + + ret = dmz_check_sb(zmd, &zmd->sb[0], false); + + /* Read and check secondary super block */ + if (ret == 0) { + sb_good[0] = true; + if (!zmd->sb[1].zone) { + unsigned int zone_id = + zmd->sb[0].zone->id + zmd->nr_meta_zones; + + zmd->sb[1].zone = dmz_get(zmd, zone_id); + } + zmd->sb[1].block = dmz_start_block(zmd, zmd->sb[1].zone); + zmd->sb[1].dev = zmd->sb[0].dev; + ret = dmz_get_sb(zmd, &zmd->sb[1], 1); + } else + ret = dmz_lookup_secondary_sb(zmd); + + if (ret) { + dmz_dev_err(zmd->sb[1].dev, "Read secondary super block failed"); + return ret; + } + + ret = dmz_check_sb(zmd, &zmd->sb[1], false); + if (ret == 0) + sb_good[1] = true; + + /* Use highest generation sb first */ + if (!sb_good[0] && !sb_good[1]) { + dmz_zmd_err(zmd, "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 (ret) { + dmz_dev_err(zmd->sb[0].dev, + "Recovery of superblock 0 failed"); + return -EIO; + } + } + + 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->sb[1].dev, + "Recovery of superblock 1 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->sb[zmd->mblk_primary].dev, + "Using super block %u (gen %llu)", + zmd->mblk_primary, zmd->sb_gen); + + if (zmd->sb_version > 1) { + int i; + struct dmz_sb *sb; + + sb = kzalloc(sizeof(struct dmz_sb), GFP_KERNEL); + if (!sb) + return -ENOMEM; + for (i = 1; i < zmd->nr_devs; i++) { + sb->block = 0; + sb->zone = dmz_get(zmd, zmd->dev[i].zone_offset); + sb->dev = &zmd->dev[i]; + if (!dmz_is_meta(sb->zone)) { + dmz_dev_err(sb->dev, + "Tertiary super block zone %u not marked as metadata zone", + sb->zone->id); + ret = -EINVAL; + goto out_kfree; + } + ret = dmz_get_sb(zmd, sb, i + 1); + if (ret) { + dmz_dev_err(sb->dev, + "Read tertiary super block failed"); + dmz_free_mblock(zmd, sb->mblk); + goto out_kfree; + } + ret = dmz_check_sb(zmd, sb, true); + dmz_free_mblock(zmd, sb->mblk); + if (ret == -EINVAL) + goto out_kfree; + } + out_kfree: + kfree(sb); + } + return ret; +} + +/* + * Initialize a zone descriptor. + */ +static int dmz_init_zone(struct blk_zone *blkz, unsigned int num, void *data) +{ + struct dmz_dev *dev = data; + struct dmz_metadata *zmd = dev->metadata; + int idx = num + dev->zone_offset; + struct dm_zone *zone; + + zone = dmz_insert(zmd, idx, dev); + if (IS_ERR(zone)) + return PTR_ERR(zone); + + if (blkz->len != zmd->zone_nr_sectors) { + if (zmd->sb_version > 1) { + /* Ignore the eventual runt (smaller) zone */ + set_bit(DMZ_OFFLINE, &zone->flags); + return 0; + } else if (blkz->start + blkz->len == dev->capacity) + return 0; + return -ENXIO; + } + + /* + * Devices that have zones with a capacity smaller than the zone size + * (e.g. NVMe zoned namespaces) are not supported. + */ + if (blkz->capacity != blkz->len) + return -ENXIO; + + switch (blkz->type) { + case BLK_ZONE_TYPE_CONVENTIONAL: + set_bit(DMZ_RND, &zone->flags); + break; + case BLK_ZONE_TYPE_SEQWRITE_REQ: + case BLK_ZONE_TYPE_SEQWRITE_PREF: + set_bit(DMZ_SEQ, &zone->flags); + break; + default: + return -ENXIO; + } + + if (dmz_is_rnd(zone)) + zone->wp_block = 0; + else + zone->wp_block = dmz_sect2blk(blkz->wp - blkz->start); + + 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); + else { + zmd->nr_useable_zones++; + if (dmz_is_rnd(zone)) { + zmd->nr_rnd_zones++; + if (zmd->nr_devs == 1 && !zmd->sb[0].zone) { + /* Primary super block zone */ + zmd->sb[0].zone = zone; + } + } + if (zmd->nr_devs > 1 && num == 0) { + /* + * Tertiary superblock zones are always at the + * start of the zoned devices, so mark them + * as metadata zone. + */ + set_bit(DMZ_META, &zone->flags); + } + } + return 0; +} + +static int dmz_emulate_zones(struct dmz_metadata *zmd, struct dmz_dev *dev) +{ + int idx; + sector_t zone_offset = 0; + + for(idx = 0; idx < dev->nr_zones; idx++) { + struct dm_zone *zone; + + zone = dmz_insert(zmd, idx, dev); + if (IS_ERR(zone)) + return PTR_ERR(zone); + set_bit(DMZ_CACHE, &zone->flags); + zone->wp_block = 0; + zmd->nr_cache_zones++; + zmd->nr_useable_zones++; + if (dev->capacity - zone_offset < zmd->zone_nr_sectors) { + /* Disable runt zone */ + set_bit(DMZ_OFFLINE, &zone->flags); + break; + } + zone_offset += zmd->zone_nr_sectors; + } + return 0; +} + +/* + * Free zones descriptors. + */ +static void dmz_drop_zones(struct dmz_metadata *zmd) +{ + int idx; + + for(idx = 0; idx < zmd->nr_zones; idx++) { + struct dm_zone *zone = xa_load(&zmd->zones, idx); + + kfree(zone); + xa_erase(&zmd->zones, idx); + } + xa_destroy(&zmd->zones); +} + +/* + * Allocate and initialize zone descriptors using the zone + * information from disk. + */ +static int dmz_init_zones(struct dmz_metadata *zmd) +{ + int i, ret; + struct dmz_dev *zoned_dev = &zmd->dev[0]; + + /* Init */ + zmd->zone_nr_sectors = zmd->dev[0].zone_nr_sectors; + zmd->zone_nr_sectors_shift = ilog2(zmd->zone_nr_sectors); + zmd->zone_nr_blocks = dmz_sect2blk(zmd->zone_nr_sectors); + zmd->zone_nr_blocks_shift = ilog2(zmd->zone_nr_blocks); + zmd->zone_bitmap_size = zmd->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, zmd->zone_nr_blocks, + DMZ_BLOCK_SIZE_BITS); + + /* Allocate zone array */ + zmd->nr_zones = 0; + for (i = 0; i < zmd->nr_devs; i++) { + struct dmz_dev *dev = &zmd->dev[i]; + + dev->metadata = zmd; + zmd->nr_zones += dev->nr_zones; + + atomic_set(&dev->unmap_nr_rnd, 0); + INIT_LIST_HEAD(&dev->unmap_rnd_list); + INIT_LIST_HEAD(&dev->map_rnd_list); + + atomic_set(&dev->unmap_nr_seq, 0); + INIT_LIST_HEAD(&dev->unmap_seq_list); + INIT_LIST_HEAD(&dev->map_seq_list); + } + + if (!zmd->nr_zones) { + DMERR("(%s): No zones found", zmd->devname); + return -ENXIO; + } + xa_init(&zmd->zones); + + DMDEBUG("(%s): Using %zu B for zone information", + zmd->devname, sizeof(struct dm_zone) * zmd->nr_zones); + + if (zmd->nr_devs > 1) { + ret = dmz_emulate_zones(zmd, &zmd->dev[0]); + if (ret < 0) { + DMDEBUG("(%s): Failed to emulate zones, error %d", + zmd->devname, ret); + dmz_drop_zones(zmd); + return ret; + } + + /* + * Primary superblock zone is always at zone 0 when multiple + * drives are present. + */ + zmd->sb[0].zone = dmz_get(zmd, 0); + + for (i = 1; i < zmd->nr_devs; i++) { + zoned_dev = &zmd->dev[i]; + + ret = blkdev_report_zones(zoned_dev->bdev, 0, + BLK_ALL_ZONES, + dmz_init_zone, zoned_dev); + if (ret < 0) { + DMDEBUG("(%s): Failed to report zones, error %d", + zmd->devname, ret); + dmz_drop_zones(zmd); + return ret; + } + } + return 0; + } + + /* + * 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. + */ + ret = blkdev_report_zones(zoned_dev->bdev, 0, BLK_ALL_ZONES, + dmz_init_zone, zoned_dev); + if (ret < 0) { + DMDEBUG("(%s): Failed to report zones, error %d", + zmd->devname, ret); + dmz_drop_zones(zmd); + return ret; + } + + return 0; +} + +static int dmz_update_zone_cb(struct blk_zone *blkz, unsigned int idx, + void *data) +{ + struct dm_zone *zone = data; + + 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; +} + +/* + * Update a zone information. + */ +static int dmz_update_zone(struct dmz_metadata *zmd, struct dm_zone *zone) +{ + struct dmz_dev *dev = zone->dev; + unsigned int noio_flag; + int ret; + + if (dev->flags & DMZ_BDEV_REGULAR) + return 0; + + /* + * Get zone information from disk. Since blkdev_report_zones() uses + * GFP_KERNEL by default for memory allocations, set the per-task + * PF_MEMALLOC_NOIO flag so that all allocations are done as if + * GFP_NOIO was specified. + */ + noio_flag = memalloc_noio_save(); + ret = blkdev_report_zones(dev->bdev, dmz_start_sect(zmd, zone), 1, + dmz_update_zone_cb, zone); + memalloc_noio_restore(noio_flag); + + if (ret == 0) + ret = -EIO; + if (ret < 0) { + dmz_dev_err(dev, "Get zone %u report failed", + zone->id); + dmz_check_bdev(dev); + return ret; + } + + 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) +{ + struct dmz_dev *dev = zone->dev; + unsigned int wp = 0; + int ret; + + wp = zone->wp_block; + ret = dmz_update_zone(zmd, zone); + if (ret) + return ret; + + dmz_dev_warn(dev, "Processing zone %u write error (zone wp %u/%u)", + zone->id, zone->wp_block, wp); + + if (zone->wp_block < wp) { + dmz_invalidate_blocks(zmd, zone, zone->wp_block, + wp - zone->wp_block); + } + + return 0; +} + +/* + * 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 = zone->dev; + + ret = blkdev_zone_mgmt(dev->bdev, REQ_OP_ZONE_RESET, + dmz_start_sect(zmd, zone), + zmd->zone_nr_sectors, GFP_NOIO); + if (ret) { + dmz_dev_err(dev, "Reset zone %u failed %d", + zone->id, 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 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 >= zmd->nr_zones) { + dmz_zmd_err(zmd, "Chunk %u mapping: invalid data zone ID %u", + chunk, dzone_id); + return -EIO; + } + + dzone = dmz_get(zmd, dzone_id); + if (!dzone) { + dmz_zmd_err(zmd, "Chunk %u mapping: data zone %u not present", + chunk, dzone_id); + return -EIO; + } + set_bit(DMZ_DATA, &dzone->flags); + dzone->chunk = chunk; + dmz_get_zone_weight(zmd, dzone); + + if (dmz_is_cache(dzone)) + list_add_tail(&dzone->link, &zmd->map_cache_list); + else if (dmz_is_rnd(dzone)) + list_add_tail(&dzone->link, &dzone->dev->map_rnd_list); + else + list_add_tail(&dzone->link, &dzone->dev->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 >= zmd->nr_zones) { + dmz_zmd_err(zmd, "Chunk %u mapping: invalid buffer zone ID %u", + chunk, bzone_id); + return -EIO; + } + + bzone = dmz_get(zmd, bzone_id); + if (!bzone) { + dmz_zmd_err(zmd, "Chunk %u mapping: buffer zone %u not present", + chunk, bzone_id); + return -EIO; + } + if (!dmz_is_rnd(bzone) && !dmz_is_cache(bzone)) { + dmz_zmd_err(zmd, "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); + if (dmz_is_cache(bzone)) + list_add_tail(&bzone->link, &zmd->map_cache_list); + else + list_add_tail(&bzone->link, &bzone->dev->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 < zmd->nr_zones; i++) { + dzone = dmz_get(zmd, i); + if (!dzone) + continue; + if (dmz_is_meta(dzone)) + continue; + if (dmz_is_offline(dzone)) + continue; + + if (dmz_is_cache(dzone)) + zmd->nr_cache++; + else if (dmz_is_rnd(dzone)) + dzone->dev->nr_rnd++; + else + dzone->dev->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_cache(dzone)) { + list_add_tail(&dzone->link, &zmd->unmap_cache_list); + atomic_inc(&zmd->unmap_nr_cache); + } else if (dmz_is_rnd(dzone)) { + list_add_tail(&dzone->link, + &dzone->dev->unmap_rnd_list); + atomic_inc(&dzone->dev->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); + set_bit(DMZ_RESERVED, &dzone->flags); + atomic_inc(&zmd->nr_reserved_seq_zones); + dzone->dev->nr_seq--; + } else { + list_add_tail(&dzone->link, + &dzone->dev->unmap_seq_list); + atomic_inc(&dzone->dev->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, &zone->dev->map_seq_list); + } else if (dmz_is_cache(zone)) { + /* LRU rotate cache zone */ + list_add_tail(&zone->link, &zmd->map_cache_list); + } else { + /* LRU rotate random zone */ + list_add_tail(&zone->link, &zone->dev->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); + set_bit(DMZ_RECLAIM_TERMINATE, &zone->flags); + wait_on_bit_timeout(&zone->flags, DMZ_RECLAIM, TASK_UNINTERRUPTIBLE, HZ); + clear_bit(DMZ_RECLAIM_TERMINATE, &zone->flags); + dmz_lock_metadata(zmd); + dmz_lock_map(zmd); +} + +/* + * Select a cache or random write zone for reclaim. + */ +static struct dm_zone *dmz_get_rnd_zone_for_reclaim(struct dmz_metadata *zmd, + unsigned int idx, bool idle) +{ + struct dm_zone *dzone = NULL; + struct dm_zone *zone, *maxw_z = NULL; + struct list_head *zone_list; + + /* If we have cache zones select from the cache zone list */ + if (zmd->nr_cache) { + zone_list = &zmd->map_cache_list; + /* Try to relaim random zones, too, when idle */ + if (idle && list_empty(zone_list)) + zone_list = &zmd->dev[idx].map_rnd_list; + } else + zone_list = &zmd->dev[idx].map_rnd_list; + + /* + * Find the buffer zone with the heaviest weight or the first (oldest) + * data zone that can be reclaimed. + */ + list_for_each_entry(zone, zone_list, link) { + if (dmz_is_buf(zone)) { + dzone = zone->bzone; + if (dmz_is_rnd(dzone) && dzone->dev->dev_idx != idx) + continue; + if (!maxw_z || maxw_z->weight < dzone->weight) + maxw_z = dzone; + } else { + dzone = zone; + if (dmz_lock_zone_reclaim(dzone)) + return dzone; + } + } + + if (maxw_z && dmz_lock_zone_reclaim(maxw_z)) + return maxw_z; + + /* + * If we come here, none of the zones inspected could be locked for + * reclaim. Try again, being more aggressive, that is, find the + * first zone that can be reclaimed regardless of its weitght. + */ + list_for_each_entry(zone, zone_list, link) { + if (dmz_is_buf(zone)) { + dzone = zone->bzone; + if (dmz_is_rnd(dzone) && dzone->dev->dev_idx != idx) + continue; + } 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, + unsigned int idx) +{ + struct dm_zone *zone; + + list_for_each_entry(zone, &zmd->dev[idx].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, + unsigned int dev_idx, bool idle) +{ + struct dm_zone *zone = NULL; + + /* + * 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, dev_idx); + if (!zone) + zone = dmz_get_rnd_zone_for_reclaim(zmd, dev_idx, idle); + 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; + int alloc_flags = zmd->nr_cache ? DMZ_ALLOC_CACHE : DMZ_ALLOC_RND; + + 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; + + /* Allocate a random zone */ + dzone = dmz_alloc_zone(zmd, 0, alloc_flags); + if (!dzone) { + if (dmz_dev_is_dying(zmd)) { + 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) { + dzone = ERR_PTR(-EIO); + goto out; + } + 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; + int alloc_flags = zmd->nr_cache ? DMZ_ALLOC_CACHE : DMZ_ALLOC_RND; + + dmz_lock_map(zmd); +again: + bzone = dzone->bzone; + if (bzone) + goto out; + + /* Allocate a random zone */ + bzone = dmz_alloc_zone(zmd, 0, alloc_flags); + if (!bzone) { + if (dmz_dev_is_dying(zmd)) { + 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, dzone->id, bzone->id); + + set_bit(DMZ_BUF, &bzone->flags); + bzone->chunk = dzone->chunk; + bzone->bzone = dzone; + dzone->bzone = bzone; + if (dmz_is_cache(bzone)) + list_add_tail(&bzone->link, &zmd->map_cache_list); + else + list_add_tail(&bzone->link, &bzone->dev->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 int dev_idx, + unsigned long flags) +{ + struct list_head *list; + struct dm_zone *zone; + int i; + + /* Schedule reclaim to ensure free zones are available */ + if (!(flags & DMZ_ALLOC_RECLAIM)) { + for (i = 0; i < zmd->nr_devs; i++) + dmz_schedule_reclaim(zmd->dev[i].reclaim); + } + + i = 0; +again: + if (flags & DMZ_ALLOC_CACHE) + list = &zmd->unmap_cache_list; + else if (flags & DMZ_ALLOC_RND) + list = &zmd->dev[dev_idx].unmap_rnd_list; + else + list = &zmd->dev[dev_idx].unmap_seq_list; + + if (list_empty(list)) { + /* + * No free zone: return NULL if this is for not reclaim. + */ + if (!(flags & DMZ_ALLOC_RECLAIM)) + return NULL; + /* + * Try to allocate from other devices + */ + if (i < zmd->nr_devs) { + dev_idx = (dev_idx + 1) % zmd->nr_devs; + i++; + goto again; + } + + /* + * Fallback to the reserved sequential zones + */ + zone = list_first_entry_or_null(&zmd->reserved_seq_zones_list, + struct dm_zone, link); + if (zone) { + 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_cache(zone)) + atomic_dec(&zmd->unmap_nr_cache); + else if (dmz_is_rnd(zone)) + atomic_dec(&zone->dev->unmap_nr_rnd); + else + atomic_dec(&zone->dev->unmap_nr_seq); + + if (dmz_is_offline(zone)) { + dmz_zmd_warn(zmd, "Zone %u is offline", zone->id); + zone = NULL; + goto again; + } + if (dmz_is_meta(zone)) { + dmz_zmd_warn(zmd, "Zone %u has metadata", zone->id); + 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_cache(zone)) { + list_add_tail(&zone->link, &zmd->unmap_cache_list); + atomic_inc(&zmd->unmap_nr_cache); + } else if (dmz_is_rnd(zone)) { + list_add_tail(&zone->link, &zone->dev->unmap_rnd_list); + atomic_inc(&zone->dev->unmap_nr_rnd); + } else if (dmz_is_reserved(zone)) { + list_add_tail(&zone->link, &zmd->reserved_seq_zones_list); + atomic_inc(&zmd->nr_reserved_seq_zones); + } else { + list_add_tail(&zone->link, &zone->dev->unmap_seq_list); + atomic_inc(&zone->dev->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, dzone->id, + DMZ_MAP_UNMAPPED); + dzone->chunk = chunk; + if (dmz_is_cache(dzone)) + list_add_tail(&dzone->link, &zmd->map_cache_list); + else if (dmz_is_rnd(dzone)) + list_add_tail(&dzone->link, &dzone->dev->map_rnd_list); + else + list_add_tail(&dzone->link, &dzone->dev->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 = zone->bzone->id; + 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)(zone->id * 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->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->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->zone_nr_blocks; + struct dmz_mblock *mblk; + unsigned int n = 0; + + dmz_zmd_debug(zmd, "=> VALIDATE zone %u, block %llu, %u blocks", + zone->id, (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_zmd_warn(zmd, "Zone %u: weight %u should be <= %u", + zone->id, 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_zmd_debug(zmd, "=> INVALIDATE zone %u, block %llu, %u blocks", + zone->id, (u64)chunk_block, nr_blocks); + + WARN_ON(chunk_block + nr_blocks > zmd->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_zmd_warn(zmd, "Zone %u: weight %u should be >= %u", + zone->id, 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->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->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->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->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->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->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_zmd_warn(zmd, "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_zmd_warn(zmd, "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); +} + +static void dmz_print_dev(struct dmz_metadata *zmd, int num) +{ + struct dmz_dev *dev = &zmd->dev[num]; + + if (bdev_zoned_model(dev->bdev) == BLK_ZONED_NONE) + dmz_dev_info(dev, "Regular block device"); + else + dmz_dev_info(dev, "Host-%s zoned block device", + bdev_zoned_model(dev->bdev) == BLK_ZONED_HA ? + "aware" : "managed"); + if (zmd->sb_version > 1) { + sector_t sector_offset = + dev->zone_offset << zmd->zone_nr_sectors_shift; + + dmz_dev_info(dev, " %llu 512-byte logical sectors (offset %llu)", + (u64)dev->capacity, (u64)sector_offset); + dmz_dev_info(dev, " %u zones of %llu 512-byte logical sectors (offset %llu)", + dev->nr_zones, (u64)zmd->zone_nr_sectors, + (u64)dev->zone_offset); + } else { + 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)zmd->zone_nr_sectors); + } +} + +/* + * Initialize the zoned metadata. + */ +int dmz_ctr_metadata(struct dmz_dev *dev, int num_dev, + struct dmz_metadata **metadata, + const char *devname) +{ + struct dmz_metadata *zmd; + unsigned int i; + struct dm_zone *zone; + int ret; + + zmd = kzalloc(sizeof(struct dmz_metadata), GFP_KERNEL); + if (!zmd) + return -ENOMEM; + + strcpy(zmd->devname, devname); + zmd->dev = dev; + zmd->nr_devs = num_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_cache, 0); + INIT_LIST_HEAD(&zmd->unmap_cache_list); + INIT_LIST_HEAD(&zmd->map_cache_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 */ + for (i = 0; i < zmd->nr_meta_zones << 1; i++) { + zone = dmz_get(zmd, zmd->sb[0].zone->id + i); + if (!zone) { + dmz_zmd_err(zmd, + "metadata zone %u not present", i); + ret = -ENXIO; + goto err; + } + if (!dmz_is_rnd(zone) && !dmz_is_cache(zone)) { + dmz_zmd_err(zmd, + "metadata zone %d is not random", i); + ret = -ENXIO; + 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_zmd_err(zmd, "Register metadata cache shrinker failed"); + goto err; + } + + dmz_zmd_info(zmd, "DM-Zoned metadata version %d", zmd->sb_version); + for (i = 0; i < zmd->nr_devs; i++) + dmz_print_dev(zmd, i); + + dmz_zmd_info(zmd, " %u zones of %llu 512-byte logical sectors", + zmd->nr_zones, (u64)zmd->zone_nr_sectors); + dmz_zmd_debug(zmd, " %u metadata zones", + zmd->nr_meta_zones * 2); + dmz_zmd_debug(zmd, " %u data zones for %u chunks", + zmd->nr_data_zones, zmd->nr_chunks); + dmz_zmd_debug(zmd, " %u cache zones (%u unmapped)", + zmd->nr_cache, atomic_read(&zmd->unmap_nr_cache)); + for (i = 0; i < zmd->nr_devs; i++) { + dmz_zmd_debug(zmd, " %u random zones (%u unmapped)", + dmz_nr_rnd_zones(zmd, i), + dmz_nr_unmap_rnd_zones(zmd, i)); + dmz_zmd_debug(zmd, " %u sequential zones (%u unmapped)", + dmz_nr_seq_zones(zmd, i), + dmz_nr_unmap_seq_zones(zmd, i)); + } + dmz_zmd_debug(zmd, " %u reserved sequential data zones", + zmd->nr_reserved_seq); + dmz_zmd_debug(zmd, "Format:"); + dmz_zmd_debug(zmd, "%u metadata blocks per set (%u max cache)", + zmd->nr_meta_blocks, zmd->max_nr_mblks); + dmz_zmd_debug(zmd, " %u data zone mapping blocks", + zmd->nr_map_blocks); + dmz_zmd_debug(zmd, " %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 dm_zone *zone; + sector_t wp_block; + unsigned int i; + int ret; + + /* Check zones */ + for (i = 0; i < zmd->nr_zones; i++) { + zone = dmz_get(zmd, i); + if (!zone) { + dmz_zmd_err(zmd, "Unable to get zone %u", i); + return -EIO; + } + wp_block = zone->wp_block; + + ret = dmz_update_zone(zmd, zone); + if (ret) { + dmz_zmd_err(zmd, "Broken zone %u", i); + return ret; + } + + if (dmz_is_offline(zone)) { + dmz_zmd_warn(zmd, "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_zmd_err(zmd, "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, + zmd->zone_nr_blocks - zone->wp_block); + } + } + + return 0; +} |