diff options
Diffstat (limited to 'drivers/md')
| -rw-r--r-- | drivers/md/Kconfig | 17 | ||||
| -rw-r--r-- | drivers/md/Makefile | 2 | ||||
| -rw-r--r-- | drivers/md/dm-zoned-metadata.c | 2509 | ||||
| -rw-r--r-- | drivers/md/dm-zoned-reclaim.c | 570 | ||||
| -rw-r--r-- | drivers/md/dm-zoned-target.c | 967 | ||||
| -rw-r--r-- | drivers/md/dm-zoned.h | 228 |
6 files changed, 4293 insertions, 0 deletions
diff --git a/drivers/md/Kconfig b/drivers/md/Kconfig index 906103c168ea..4a249ee86364 100644 --- a/drivers/md/Kconfig +++ b/drivers/md/Kconfig @@ -521,6 +521,23 @@ config DM_INTEGRITY To compile this code as a module, choose M here: the module will be called dm-integrity. +config DM_ZONED + tristate "Drive-managed zoned block device target support" + depends on BLK_DEV_DM + depends on BLK_DEV_ZONED + ---help--- + This device-mapper target takes a host-managed or host-aware zoned + block device and exposes most of its capacity as a regular block + device (drive-managed zoned block device) without any write + constraints. This is mainly intended for use with file systems that + do not natively support zoned block devices but still want to + benefit from the increased capacity offered by SMR disks. Other uses + by applications using raw block devices (for example object stores) + are also possible. + + To compile this code as a module, choose M here: the module will + be called dm-zoned. + If unsure, say N. endif # MD diff --git a/drivers/md/Makefile b/drivers/md/Makefile index 913720bd81c1..786ec9e86d65 100644 --- a/drivers/md/Makefile +++ b/drivers/md/Makefile @@ -20,6 +20,7 @@ dm-era-y += dm-era-target.o dm-verity-y += dm-verity-target.o md-mod-y += md.o bitmap.o raid456-y += raid5.o raid5-cache.o raid5-ppl.o +dm-zoned-y += dm-zoned-target.o dm-zoned-metadata.o dm-zoned-reclaim.o # Note: link order is important. All raid personalities # and must come before md.o, as they each initialise @@ -60,6 +61,7 @@ obj-$(CONFIG_DM_CACHE_SMQ) += dm-cache-smq.o obj-$(CONFIG_DM_ERA) += dm-era.o obj-$(CONFIG_DM_LOG_WRITES) += dm-log-writes.o obj-$(CONFIG_DM_INTEGRITY) += dm-integrity.o +obj-$(CONFIG_DM_ZONED) += dm-zoned.o ifeq ($(CONFIG_DM_UEVENT),y) dm-mod-objs += dm-uevent.o diff --git a/drivers/md/dm-zoned-metadata.c b/drivers/md/dm-zoned-metadata.c new file mode 100644 index 000000000000..4618441cc412 --- /dev/null +++ b/drivers/md/dm-zoned-metadata.c @@ -0,0 +1,2509 @@ +/* + * 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; + atomic_t ref; + unsigned long state; + struct page *page; + void *data; +}; + +/* + * Metadata block state flags. + */ +enum { + DMZ_META_DIRTY, + DMZ_META_READING, + DMZ_META_WRITING, + DMZ_META_ERROR, +}; + +/* + * Super block information (one per metadata set). + */ +struct dmz_sb { + sector_t block; + struct dmz_mblock *mblk; + struct dmz_super *sb; +}; + +/* + * In-memory metadata. + */ +struct dmz_metadata { + struct dmz_dev *dev; + + sector_t zone_bitmap_size; + unsigned int zone_nr_bitmap_blocks; + + unsigned int nr_bitmap_blocks; + unsigned int nr_map_blocks; + + unsigned int nr_useable_zones; + unsigned int nr_meta_blocks; + unsigned int nr_meta_zones; + unsigned int nr_data_zones; + unsigned int nr_rnd_zones; + unsigned int nr_reserved_seq; + unsigned int nr_chunks; + + /* Zone information array */ + struct dm_zone *zones; + + struct dm_zone *sb_zone; + struct dmz_sb sb[2]; + unsigned int mblk_primary; + u64 sb_gen; + unsigned int min_nr_mblks; + unsigned int max_nr_mblks; + atomic_t nr_mblks; + struct rw_semaphore mblk_sem; + struct mutex mblk_flush_lock; + spinlock_t mblk_lock; + struct rb_root mblk_rbtree; + struct list_head mblk_lru_list; + struct list_head mblk_dirty_list; + struct shrinker mblk_shrinker; + + /* Zone allocation management */ + struct mutex map_lock; + struct dmz_mblock **map_mblk; + unsigned int nr_rnd; + atomic_t unmap_nr_rnd; + struct list_head unmap_rnd_list; + struct list_head map_rnd_list; + + unsigned int nr_seq; + atomic_t unmap_nr_seq; + struct list_head unmap_seq_list; + struct list_head map_seq_list; + + atomic_t nr_reserved_seq_zones; + struct list_head reserved_seq_zones_list; + + wait_queue_head_t free_wq; +}; + +/* + * Various accessors + */ +unsigned int dmz_id(struct dmz_metadata *zmd, struct dm_zone *zone) +{ + return ((unsigned int)(zone - zmd->zones)); +} + +sector_t dmz_start_sect(struct dmz_metadata *zmd, struct dm_zone *zone) +{ + return dmz_id(zmd, zone) << zmd->dev->zone_nr_sectors_shift; +} + +sector_t dmz_start_block(struct dmz_metadata *zmd, struct dm_zone *zone) +{ + return 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); + atomic_set(&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. + */ +static struct dmz_mblock *dmz_lookup_mblock(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) + 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 a metadata block from disk. + */ +static struct dmz_mblock *dmz_fetch_mblock(struct dmz_metadata *zmd, + sector_t mblk_no) +{ + struct dmz_mblock *mblk; + sector_t block = zmd->sb[zmd->mblk_primary].block + mblk_no; + struct bio *bio; + + /* Get block and insert it */ + mblk = dmz_alloc_mblock(zmd, mblk_no); + if (!mblk) + return NULL; + + spin_lock(&zmd->mblk_lock); + atomic_inc(&mblk->ref); + set_bit(DMZ_META_READING, &mblk->state); + dmz_insert_mblock(zmd, mblk); + spin_unlock(&zmd->mblk_lock); + + bio = bio_alloc(GFP_NOIO, 1); + if (!bio) { + dmz_free_mblock(zmd, mblk); + return NULL; + } + + bio->bi_iter.bi_sector = dmz_blk2sect(block); + bio->bi_bdev = 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); + + if (atomic_dec_and_test(&mblk->ref)) { + 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_lookup_mblock(zmd, mblk_no); + if (mblk) { + /* Cache hit: remove block from LRU list */ + if (atomic_inc_return(&mblk->ref) == 1 && + !test_bit(DMZ_META_DIRTY, &mblk->state)) + list_del_init(&mblk->link); + } + spin_unlock(&zmd->mblk_lock); + + if (!mblk) { + /* Cache miss: read the block from disk */ + mblk = dmz_fetch_mblock(zmd, mblk_no); + if (!mblk) + return ERR_PTR(-ENOMEM); + } + + /* Wait for on-going read I/O and check for error */ + wait_on_bit_io(&mblk->state, DMZ_META_READING, + TASK_UNINTERRUPTIBLE); + if (test_bit(DMZ_META_ERROR, &mblk->state)) { + dmz_release_mblock(zmd, mblk); + return ERR_PTR(-EIO); + } + + return mblk; +} + +/* + * Mark a metadata block dirty. + */ +static void dmz_dirty_mblock(struct dmz_metadata *zmd, struct dmz_mblock *mblk) +{ + spin_lock(&zmd->mblk_lock); + if (!test_and_set_bit(DMZ_META_DIRTY, &mblk->state)) + list_add_tail(&mblk->link, &zmd->mblk_dirty_list); + spin_unlock(&zmd->mblk_lock); +} + +/* + * Issue a metadata block write BIO. + */ +static void dmz_write_mblock(struct dmz_metadata *zmd, struct dmz_mblock *mblk, + unsigned int set) +{ + sector_t block = zmd->sb[set].block + mblk->no; + struct bio *bio; + + bio = bio_alloc(GFP_NOIO, 1); + if (!bio) { + set_bit(DMZ_META_ERROR, &mblk->state); + return; + } + + set_bit(DMZ_META_WRITING, &mblk->state); + + bio->bi_iter.bi_sector = dmz_blk2sect(block); + bio->bi_bdev = zmd->dev->bdev; + bio->bi_private = mblk; + bio->bi_end_io = dmz_mblock_bio_end_io; + bio_set_op_attrs(bio, REQ_OP_WRITE, REQ_META | REQ_PRIO); + bio_add_page(bio, mblk->page, DMZ_BLOCK_SIZE, 0); + submit_bio(bio); +} + +/* + * Read/write a metadata block. + */ +static int dmz_rdwr_block(struct dmz_metadata *zmd, int op, sector_t block, + struct page *page) +{ + struct bio *bio; + int ret; + + bio = bio_alloc(GFP_NOIO, 1); + if (!bio) + return -ENOMEM; + + bio->bi_iter.bi_sector = dmz_blk2sect(block); + bio->bi_bdev = zmd->dev->bdev; + bio_set_op_attrs(bio, op, REQ_SYNC | REQ_META | REQ_PRIO); + bio_add_page(bio, page, DMZ_BLOCK_SIZE, 0); + ret = submit_bio_wait(bio); + bio_put(bio); + + return ret; +} + +/* + * Write super block of the specified metadata set. + */ +static int dmz_write_sb(struct dmz_metadata *zmd, unsigned int set) +{ + sector_t block = zmd->sb[set].block; + struct dmz_mblock *mblk = zmd->sb[set].mblk; + struct dmz_super *sb = zmd->sb[set].sb; + u64 sb_gen = zmd->sb_gen + 1; + int ret; + + sb->magic = cpu_to_le32(DMZ_MAGIC); + sb->version = cpu_to_le32(DMZ_META_VER); + + sb->gen = cpu_to_le64(sb_gen); + + sb->sb_block = cpu_to_le64(block); + sb->nr_meta_blocks = cpu_to_le32(zmd->nr_meta_blocks); + sb->nr_reserved_seq = cpu_to_le32(zmd->nr_reserved_seq); + sb->nr_chunks = cpu_to_le32(zmd->nr_chunks); + + sb->nr_map_blocks = cpu_to_le32(zmd->nr_map_blocks); + sb->nr_bitmap_blocks = cpu_to_le32(zmd->nr_bitmap_blocks); + + sb->crc = 0; + sb->crc = cpu_to_le32(crc32_le(sb_gen, (unsigned char *)sb, DMZ_BLOCK_SIZE)); + + ret = dmz_rdwr_block(zmd, REQ_OP_WRITE, block, mblk->page); + if (ret == 0) + ret = blkdev_issue_flush(zmd->dev->bdev, GFP_KERNEL, NULL); + + return ret; +} + +/* + * Write dirty metadata blocks to the specified set. + */ +static int dmz_write_dirty_mblocks(struct dmz_metadata *zmd, + struct list_head *write_list, + unsigned int set) +{ + struct dmz_mblock *mblk; + struct blk_plug plug; + int ret = 0; + + /* Issue writes */ + blk_start_plug(&plug); + list_for_each_entry(mblk, write_list, link) + dmz_write_mblock(zmd, mblk, set); + blk_finish_plug(&plug); + + /* Wait for completion */ + list_for_each_entry(mblk, write_list, link) { + wait_on_bit_io(&mblk->state, DMZ_META_WRITING, + TASK_UNINTERRUPTIBLE); + if (test_bit(DMZ_META_ERROR, &mblk->state)) { + clear_bit(DMZ_META_ERROR, &mblk->state); + ret = -EIO; + } + } + + /* Flush drive cache (this will also sync data) */ + if (ret == 0) + ret = blkdev_issue_flush(zmd->dev->bdev, GFP_KERNEL, NULL); + + return ret; +} + +/* + * Log dirty metadata blocks. + */ +static int dmz_log_dirty_mblocks(struct dmz_metadata *zmd, + struct list_head *write_list) +{ + unsigned int log_set = zmd->mblk_primary ^ 0x1; + int ret; + + /* Write dirty blocks to the log */ + ret = dmz_write_dirty_mblocks(zmd, write_list, log_set); + if (ret) + return ret; + + /* + * No error so far: now validate the log by updating the + * log index super block generation. + */ + ret = dmz_write_sb(zmd, log_set); + if (ret) + return ret; + + return 0; +} + +/* + * Flush dirty metadata blocks. + */ +int dmz_flush_metadata(struct dmz_metadata *zmd) +{ + struct dmz_mblock *mblk; + struct list_head write_list; + int ret; + + if (WARN_ON(!zmd)) + return 0; + + INIT_LIST_HEAD(&write_list); + + /* + * Make sure that metadata blocks are stable before logging: take + * the write lock on the metadata semaphore to prevent target BIOs + * from modifying metadata. + */ + down_write(&zmd->mblk_sem); + + /* + * This is called from the target flush work and reclaim work. + * Concurrent execution is not allowed. + */ + dmz_lock_flush(zmd); + + /* Get dirty blocks */ + spin_lock(&zmd->mblk_lock); + list_splice_init(&zmd->mblk_dirty_list, &write_list); + spin_unlock(&zmd->mblk_lock); + + /* If there are no dirty metadata blocks, just flush the device cache */ + if (list_empty(&write_list)) { + ret = blkdev_issue_flush(zmd->dev->bdev, GFP_KERNEL, NULL); + goto out; + } + + /* + * The primary metadata set is still clean. Keep it this way until + * all updates are successful in the secondary set. That is, use + * the secondary set as a log. + */ + ret = dmz_log_dirty_mblocks(zmd, &write_list); + if (ret) + goto out; + + /* + * The log is on disk. It is now safe to update in place + * in the primary metadata set. + */ + ret = dmz_write_dirty_mblocks(zmd, &write_list, zmd->mblk_primary); + if (ret) + goto out; + + ret = dmz_write_sb(zmd, zmd->mblk_primary); + if (ret) + goto out; + + while (!list_empty(&write_list)) { + mblk = list_first_entry(&write_list, struct dmz_mblock, link); + list_del_init(&mblk->link); + + spin_lock(&zmd->mblk_lock); + clear_bit(DMZ_META_DIRTY, &mblk->state); + if (atomic_read(&mblk->ref) == 0) + list_add_tail(&mblk->link, &zmd->mblk_lru_list); + spin_unlock(&zmd->mblk_lock); + } + + zmd->sb_gen++; +out: + if (ret && !list_empty(&write_list)) { + spin_lock(&zmd->mblk_lock); + list_splice(&write_list, &zmd->mblk_dirty_list); + spin_unlock(&zmd->mblk_lock); + } + + dmz_unlock_flush(zmd); + up_write(&zmd->mblk_sem); + + return ret; +} + +/* + * Check super block. + */ +static int dmz_check_sb(struct dmz_metadata *zmd, struct dmz_super *sb) +{ + unsigned int nr_meta_zones, nr_data_zones; + struct dmz_dev *dev = zmd->dev; + u32 crc, stored_crc; + u64 gen; + + gen = le64_to_cpu(sb->gen); + stored_crc = le32_to_cpu(sb->crc); + sb->crc = 0; + crc = crc32_le(gen, (unsigned char *)sb, DMZ_BLOCK_SIZE); + if (crc != stored_crc) { + dmz_dev_err(dev, "Invalid checksum (needed 0x%08x, got 0x%08x)", + crc, stored_crc); + return -ENXIO; + } + + if (le32_to_cpu(sb->magic) != DMZ_MAGIC) { + dmz_dev_err(dev, "Invalid meta magic (needed 0x%08x, got 0x%08x)", + DMZ_MAGIC, le32_to_cpu(sb->magic)); + return -ENXIO; + } + + if (le32_to_cpu(sb->version) != DMZ_META_VER) { + dmz_dev_err(dev, "Invalid meta version (needed %d, got %d)", + DMZ_META_VER, le32_to_cpu(sb->version)); + return -ENXIO; + } + + nr_meta_zones = (le32_to_cpu(sb->nr_meta_blocks) + dev->zone_nr_blocks - 1) + >> dev->zone_nr_blocks_shift; + if (!nr_meta_zones || + nr_meta_zones >= zmd->nr_rnd_zones) { + dmz_dev_err(dev, "Invalid number of metadata blocks"); + return -ENXIO; + } + + if (!le32_to_cpu(sb->nr_reserved_seq) || + le32_to_cpu(sb->nr_reserved_seq) >= (zmd->nr_useable_zones - nr_meta_zones)) { + dmz_dev_err(dev, "Invalid number of reserved sequential zones"); + return -ENXIO; + } + + nr_data_zones = zmd->nr_useable_zones - + (nr_meta_zones * 2 + le32_to_cpu(sb->nr_reserved_seq)); + if (le32_to_cpu(sb->nr_chunks) > nr_data_zones) { + dmz_dev_err(dev, "Invalid number of chunks %u / %u", + le32_to_cpu(sb->nr_chunks), nr_data_zones); + return -ENXIO; + } + + /* OK */ + zmd->nr_meta_blocks = le32_to_cpu(sb->nr_meta_blocks); + zmd->nr_reserved_seq = le32_to_cpu(sb->nr_reserved_seq); + zmd->nr_chunks = le32_to_cpu(sb->nr_chunks); + zmd->nr_map_blocks = le32_to_cpu(sb->nr_map_blocks); + zmd->nr_bitmap_blocks = le32_to_cpu(sb->nr_bitmap_blocks); + zmd->nr_meta_zones = nr_meta_zones; + zmd->nr_data_zones = nr_data_zones; + + return 0; +} + +/* + * Read the first or second super block from disk. + */ +static int dmz_read_sb(struct dmz_metadata *zmd, unsigned int set) +{ + return dmz_rdwr_block(zmd, REQ_OP_READ, zmd->sb[set].block, + zmd->sb[set].mblk->page); +} + +/* + * Determine the position of the secondary super blocks on disk. + * This is used only if a corruption of the primary super block + * is detected. + */ +static int dmz_lookup_secondary_sb(struct dmz_metadata *zmd) +{ + unsigned int zone_nr_blocks = zmd->dev->zone_nr_blocks; + struct dmz_mblock *mblk; + int i; + + /* Allocate a block */ + mblk = dmz_alloc_mblock(zmd, 0); + if (!mblk) + return -ENOMEM; + + zmd->sb[1].mblk = mblk; + zmd->sb[1].sb = mblk->data; + + /* Bad first super block: search for the second one */ + zmd->sb[1].block = zmd->sb[0].block + zone_nr_blocks; + for (i = 0; i < zmd->nr_rnd_zones - 1; i++) { + if (dmz_read_sb(zmd, 1) != 0) + break; + if (le32_to_cpu(zmd->sb[1].sb->magic) == DMZ_MAGIC) + return 0; + zmd->sb[1].block += zone_nr_blocks; + } + + dmz_free_mblock(zmd, mblk); + zmd->sb[1].mblk = NULL; + + return -EIO; +} + +/* + * Read the first or second super block from disk. + */ +static int dmz_get_sb(struct dmz_metadata *zmd, unsigned int set) +{ + struct dmz_mblock *mblk; + int ret; + + /* Allocate a block */ + mblk = dmz_alloc_mblock(zmd, 0); + if (!mblk) + return -ENOMEM; + + zmd->sb[set].mblk = mblk; + zmd->sb[set].sb = mblk->data; + + /* Read super block */ + ret = dmz_read_sb(zmd, set); + if (ret) { + dmz_free_mblock(zmd, mblk); + zmd->sb[set].mblk = NULL; + return ret; + } + + return 0; +} + +/* + * Recover a metadata set. + */ +static int dmz_recover_mblocks(struct dmz_metadata *zmd, unsigned int dst_set) +{ + unsigned int src_set = dst_set ^ 0x1; + struct page *page; + int i, ret; + + dmz_dev_warn(zmd->dev, "Metadata set %u invalid: recovering", dst_set); + + if (dst_set == 0) + zmd->sb[0].block = dmz_start_block(zmd, zmd->sb_zone); + else { + zmd->sb[1].block = zmd->sb[0].block + + (zmd->nr_meta_zones << zmd->dev->zone_nr_blocks_shift); + } + + page = alloc_page(GFP_KERNEL); + if (!page) + return -ENOMEM; + + /* Copy metadata blocks */ + for (i = 1; i < zmd->nr_meta_blocks; i++) { + ret = dmz_rdwr_block(zmd, REQ_OP_READ, + zmd->sb[src_set].block + i, page); + if (ret) + goto out; + ret = dmz_rdwr_block(zmd, REQ_OP_WRITE, + zmd->sb[dst_set].block + i, page); + if (ret) + goto out; + } + + /* Finalize with the super block */ + if (!zmd->sb[dst_set].mblk) { + zmd->sb[dst_set].mblk = dmz_alloc_mblock(zmd, 0); + if (!zmd->sb[dst_set].mblk) { + ret = -ENOMEM; + goto out; + } + zmd->sb[dst_set].sb = zmd->sb[dst_set].mblk->data; + } + + ret = dmz_write_sb(zmd, dst_set); +out: + __free_pages(page, 0); + + return ret; +} + +/* + * Get super block from disk. + */ +static int dmz_load_sb(struct dmz_metadata *zmd) +{ + bool sb_good[2] = {false, false}; + u64 sb_gen[2] = {0, 0}; + int ret; + + /* Read and check the primary super block */ + zmd->sb[0].block = dmz_start_block(zmd, zmd->sb_zone); + ret = dmz_get_sb(zmd, 0); + if (ret) { + dmz_dev_err(zmd->dev, "Read primary super block failed"); + return ret; + } + + ret = dmz_check_sb(zmd, zmd->sb[0].sb); + + /* Read and check secondary super block */ + if (ret == 0) { + sb_good[0] = true; + zmd->sb[1].block = zmd->sb[0].block + + (zmd->nr_meta_zones << zmd->dev->zone_nr_blocks_shift); + ret = dmz_get_sb(zmd, 1); + } else + ret = dmz_lookup_secondary_sb(zmd); + + if (ret) { + dmz_dev_err(zmd->dev, "Read secondary super block failed"); + return ret; + } + + ret = dmz_check_sb(zmd, zmd->sb[1].sb); + if (ret == 0) + sb_good[1] = true; + + /* Use highest generation sb first */ + if (!sb_good[0] && !sb_good[1]) { + dmz_dev_err(zmd->dev, "No valid super block found"); + return -EIO; + } + + if (sb_good[0]) + sb_gen[0] = le64_to_cpu(zmd->sb[0].sb->gen); + else + ret = dmz_recover_mblocks(zmd, 0); + + if (sb_good[1]) + sb_gen[1] = le64_to_cpu(zmd->sb[1].sb->gen); + else + ret = dmz_recover_mblocks(zmd, 1); + + if (ret) { + dmz_dev_err(zmd->dev, "Recovery failed"); + return -EIO; + } + + if (sb_gen[0] >= sb_gen[1]) { + zmd->sb_gen = sb_gen[0]; + zmd->mblk_primary = 0; + } else { + zmd->sb_gen = sb_gen[1]; + zmd->mblk_primary = 1; + } + + dmz_dev_debug(zmd->dev, "Using super block %u (gen %llu)", + zmd->mblk_primary, zmd->sb_gen); + + return 0; +} + +/* + * Initialize a zone descriptor. + */ +static int dmz_init_zone(struct dmz_metadata *zmd, struct dm_zone *zone, + struct blk_zone *blkz) +{ + struct dmz_dev *dev = zmd->dev; + + /* Ignore the eventual last runt (smaller) zone */ + if (blkz->len != dev->zone_nr_sectors) { + if (blkz->start + blkz->len == dev->capacity) + return 0; + return -ENXIO; + } + + INIT_LIST_HEAD(&zone->link); + atomic_set(&zone->refcount, 0); + zone->chunk = DMZ_MAP_UNMAPPED; + + if (blkz->type == BLK_ZONE_TYPE_CONVENTIONAL) { + set_bit(DMZ_RND, &zone->flags); + zmd->nr_rnd_zones++; + } else if (blkz->type == BLK_ZONE_TYPE_SEQWRITE_REQ || + blkz->type == BLK_ZONE_TYPE_SEQWRITE_PREF) { + set_bit(DMZ_SEQ, &zone->flags); + } else + return -ENXIO; + + if (blkz->cond == BLK_ZONE_COND_OFFLINE) + set_bit(DMZ_OFFLINE, &zone->flags); + else if (blkz->cond == BLK_ZONE_COND_READONLY) + set_bit(DMZ_READ_ONLY, &zone->flags); + + if (dmz_is_rnd(zone)) + zone->wp_block = 0; + else + zone->wp_block = dmz_sect2blk(blkz->wp - blkz->start); + + if (!dmz_is_offline(zone) && !dmz_is_readonly(zone)) { + zmd->nr_useable_zones++; + if (dmz_is_rnd(zone)) { + zmd->nr_rnd_zones++; + if (!zmd->sb_zone) { + /* Super block zone */ + zmd->sb_zone = zone; + } + } + } + + return 0; +} + +/* + * Free zones descriptors. + */ +static void dmz_drop_zones(struct dmz_metadata *zmd) +{ + kfree(zmd->zones); + zmd->zones = NULL; +} + +/* + * The size of a zone report in number of zones. + * This results in 4096*64B=256KB report zones commands. + */ +#define DMZ_REPORT_NR_ZONES 4096 + +/* + * Allocate and initialize zone descriptors using the zone + * information from disk. + */ +static int dmz_init_zones(struct dmz_metadata *zmd) +{ + struct dmz_dev *dev = zmd->dev; + struct dm_zone *zone; + struct blk_zone *blkz; + unsigned int nr_blkz; + sector_t sector = 0; + int i, ret = 0; + + /* Init */ + zmd->zone_bitmap_size = dev->zone_nr_blocks >> 3; + zmd->zone_nr_bitmap_blocks = zmd->zone_bitmap_size >> DMZ_BLOCK_SHIFT; + + /* Allocate zone array */ + zmd->zones = kcalloc(dev->nr_zones, sizeof(struct dm_zone), GFP_KERNEL); + if (!zmd->zones) + return -ENOMEM; + + dmz_dev_info(dev, "Using %zu B for zone information", + sizeof(struct dm_zone) * dev->nr_zones); + + /* Get zone information */ + nr_blkz = DMZ_REPORT_NR_ZONES; + blkz = kcalloc(nr_blkz, sizeof(struct blk_zone), GFP_KERNEL); + if (!blkz) { + ret = -ENOMEM; + goto out; + } + + /* + * Get zone information and initialize zone descriptors. + * At the same time, determine where the super block + * should be: first block of the first randomly writable + * zone. + */ + zone = zmd->zones; + while (sector < dev->capacity) { + /* Get zone information */ + nr_blkz = DMZ_REPORT_NR_ZONES; + ret = blkdev_report_zones(dev->bdev, sector, blkz, + &nr_blkz, GFP_KERNEL); + if (ret) { + dmz_dev_err(dev, "Report zones failed %d", ret); + goto out; + } + |