From 0af3d00bad38d3bb9912a60928ad0669f17bdb76 Mon Sep 17 00:00:00 2001 From: Josef Bacik Date: Mon, 21 Jun 2010 14:48:16 -0400 Subject: [PATCH] Btrfs: create special free space cache inode In order to save free space cache, we need an inode to hold the data, and we need a special item to point at the right inode for the right block group. So first, create a special item that will point to the right inode, and the number of extent entries we will have and the number of bitmaps we will have. We truncate and pre-allocate space everytime to make sure it's uptodate. This feature will be turned on as soon as you mount with -o space_cache, however it is safe to boot into old kernels, they will just generate the cache the old fashion way. When you boot back into a newer kernel we will notice that we modified and not the cache and automatically discard the cache. Signed-off-by: Josef Bacik --- fs/btrfs/ctree.h | 74 +++++++++++- fs/btrfs/disk-io.c | 3 +- fs/btrfs/extent-tree.c | 231 +++++++++++++++++++++++++++++++++++- fs/btrfs/free-space-cache.c | 155 ++++++++++++++++++++++++ fs/btrfs/free-space-cache.h | 11 ++ fs/btrfs/inode.c | 95 ++++++++++++--- fs/btrfs/relocation.c | 91 +++++++++++++- fs/btrfs/super.c | 7 +- fs/btrfs/transaction.c | 43 +++++-- fs/btrfs/transaction.h | 4 + 10 files changed, 668 insertions(+), 46 deletions(-) diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index eaf286abad17..46f52e1beade 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -99,6 +99,9 @@ struct btrfs_ordered_sum; */ #define BTRFS_EXTENT_CSUM_OBJECTID -10ULL +/* For storing free space cache */ +#define BTRFS_FREE_SPACE_OBJECTID -11ULL + /* dummy objectid represents multiple objectids */ #define BTRFS_MULTIPLE_OBJECTIDS -255ULL @@ -265,6 +268,22 @@ struct btrfs_chunk { /* additional stripes go here */ } __attribute__ ((__packed__)); +#define BTRFS_FREE_SPACE_EXTENT 1 +#define BTRFS_FREE_SPACE_BITMAP 2 + +struct btrfs_free_space_entry { + __le64 offset; + __le64 bytes; + u8 type; +} __attribute__ ((__packed__)); + +struct btrfs_free_space_header { + struct btrfs_disk_key location; + __le64 generation; + __le64 num_entries; + __le64 num_bitmaps; +} __attribute__ ((__packed__)); + static inline unsigned long btrfs_chunk_item_size(int num_stripes) { BUG_ON(num_stripes == 0); @@ -365,8 +384,10 @@ struct btrfs_super_block { char label[BTRFS_LABEL_SIZE]; + __le64 cache_generation; + /* future expansion */ - __le64 reserved[32]; + __le64 reserved[31]; u8 sys_chunk_array[BTRFS_SYSTEM_CHUNK_ARRAY_SIZE]; } __attribute__ ((__packed__)); @@ -375,12 +396,12 @@ struct btrfs_super_block { * ones specified below then we will fail to mount */ #define BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF (1ULL << 0) -#define BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL (2ULL << 0) +#define BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL (1ULL << 1) #define BTRFS_FEATURE_COMPAT_SUPP 0ULL #define BTRFS_FEATURE_COMPAT_RO_SUPP 0ULL -#define BTRFS_FEATURE_INCOMPAT_SUPP \ - (BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF | \ +#define BTRFS_FEATURE_INCOMPAT_SUPP \ + (BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF | \ BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL) /* @@ -750,6 +771,14 @@ enum btrfs_caching_type { BTRFS_CACHE_FINISHED = 2, }; +enum btrfs_disk_cache_state { + BTRFS_DC_WRITTEN = 0, + BTRFS_DC_ERROR = 1, + BTRFS_DC_CLEAR = 2, + BTRFS_DC_SETUP = 3, + BTRFS_DC_NEED_WRITE = 4, +}; + struct btrfs_caching_control { struct list_head list; struct mutex mutex; @@ -763,6 +792,7 @@ struct btrfs_block_group_cache { struct btrfs_key key; struct btrfs_block_group_item item; struct btrfs_fs_info *fs_info; + struct inode *inode; spinlock_t lock; u64 pinned; u64 reserved; @@ -773,8 +803,11 @@ struct btrfs_block_group_cache { int extents_thresh; int free_extents; int total_bitmaps; - int ro; - int dirty; + int ro:1; + int dirty:1; + int iref:1; + + int disk_cache_state; /* cache tracking stuff */ int cached; @@ -1192,6 +1225,7 @@ struct btrfs_root { #define BTRFS_MOUNT_NOSSD (1 << 9) #define BTRFS_MOUNT_DISCARD (1 << 10) #define BTRFS_MOUNT_FORCE_COMPRESS (1 << 11) +#define BTRFS_MOUNT_SPACE_CACHE (1 << 12) #define btrfs_clear_opt(o, opt) ((o) &= ~BTRFS_MOUNT_##opt) #define btrfs_set_opt(o, opt) ((o) |= BTRFS_MOUNT_##opt) @@ -1665,6 +1699,27 @@ static inline void btrfs_set_dir_item_key(struct extent_buffer *eb, write_eb_member(eb, item, struct btrfs_dir_item, location, key); } +BTRFS_SETGET_FUNCS(free_space_entries, struct btrfs_free_space_header, + num_entries, 64); +BTRFS_SETGET_FUNCS(free_space_bitmaps, struct btrfs_free_space_header, + num_bitmaps, 64); +BTRFS_SETGET_FUNCS(free_space_generation, struct btrfs_free_space_header, + generation, 64); + +static inline void btrfs_free_space_key(struct extent_buffer *eb, + struct btrfs_free_space_header *h, + struct btrfs_disk_key *key) +{ + read_eb_member(eb, h, struct btrfs_free_space_header, location, key); +} + +static inline void btrfs_set_free_space_key(struct extent_buffer *eb, + struct btrfs_free_space_header *h, + struct btrfs_disk_key *key) +{ + write_eb_member(eb, h, struct btrfs_free_space_header, location, key); +} + /* struct btrfs_disk_key */ BTRFS_SETGET_STACK_FUNCS(disk_key_objectid, struct btrfs_disk_key, objectid, 64); @@ -1876,6 +1931,8 @@ BTRFS_SETGET_STACK_FUNCS(super_incompat_flags, struct btrfs_super_block, incompat_flags, 64); BTRFS_SETGET_STACK_FUNCS(super_csum_type, struct btrfs_super_block, csum_type, 16); +BTRFS_SETGET_STACK_FUNCS(super_cache_generation, struct btrfs_super_block, + cache_generation, 64); static inline int btrfs_super_csum_size(struct btrfs_super_block *s) { @@ -2115,6 +2172,7 @@ int btrfs_set_block_group_ro(struct btrfs_root *root, struct btrfs_block_group_cache *cache); int btrfs_set_block_group_rw(struct btrfs_root *root, struct btrfs_block_group_cache *cache); +void btrfs_put_block_group_cache(struct btrfs_fs_info *info); /* ctree.c */ int btrfs_bin_search(struct extent_buffer *eb, struct btrfs_key *key, int level, int *slot); @@ -2426,6 +2484,10 @@ void btrfs_run_delayed_iputs(struct btrfs_root *root); int btrfs_prealloc_file_range(struct inode *inode, int mode, u64 start, u64 num_bytes, u64 min_size, loff_t actual_len, u64 *alloc_hint); +int btrfs_prealloc_file_range_trans(struct inode *inode, + struct btrfs_trans_handle *trans, int mode, + u64 start, u64 num_bytes, u64 min_size, + loff_t actual_len, u64 *alloc_hint); extern const struct dentry_operations btrfs_dentry_operations; /* ioctl.c */ diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 64f10082f048..45cf64fc1e3e 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -1685,7 +1685,6 @@ struct btrfs_root *open_ctree(struct super_block *sb, __setup_root(4096, 4096, 4096, 4096, tree_root, fs_info, BTRFS_ROOT_TREE_OBJECTID); - bh = btrfs_read_dev_super(fs_devices->latest_bdev); if (!bh) goto fail_iput; @@ -1993,6 +1992,7 @@ struct btrfs_root *open_ctree(struct super_block *sb, if (!(sb->s_flags & MS_RDONLY)) { down_read(&fs_info->cleanup_work_sem); btrfs_orphan_cleanup(fs_info->fs_root); + btrfs_orphan_cleanup(fs_info->tree_root); up_read(&fs_info->cleanup_work_sem); } @@ -2421,6 +2421,7 @@ int close_ctree(struct btrfs_root *root) fs_info->closing = 1; smp_mb(); + btrfs_put_block_group_cache(fs_info); if (!(fs_info->sb->s_flags & MS_RDONLY)) { ret = btrfs_commit_super(root); if (ret) diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 32d094002a57..aab40fb3faed 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -2688,6 +2688,109 @@ next_block_group(struct btrfs_root *root, return cache; } +static int cache_save_setup(struct btrfs_block_group_cache *block_group, + struct btrfs_trans_handle *trans, + struct btrfs_path *path) +{ + struct btrfs_root *root = block_group->fs_info->tree_root; + struct inode *inode = NULL; + u64 alloc_hint = 0; + int num_pages = 0; + int retries = 0; + int ret = 0; + + /* + * If this block group is smaller than 100 megs don't bother caching the + * block group. + */ + if (block_group->key.offset < (100 * 1024 * 1024)) { + spin_lock(&block_group->lock); + block_group->disk_cache_state = BTRFS_DC_WRITTEN; + spin_unlock(&block_group->lock); + return 0; + } + +again: + inode = lookup_free_space_inode(root, block_group, path); + if (IS_ERR(inode) && PTR_ERR(inode) != -ENOENT) { + ret = PTR_ERR(inode); + btrfs_release_path(root, path); + goto out; + } + + if (IS_ERR(inode)) { + BUG_ON(retries); + retries++; + + if (block_group->ro) + goto out_free; + + ret = create_free_space_inode(root, trans, block_group, path); + if (ret) + goto out_free; + goto again; + } + + /* + * We want to set the generation to 0, that way if anything goes wrong + * from here on out we know not to trust this cache when we load up next + * time. + */ + BTRFS_I(inode)->generation = 0; + ret = btrfs_update_inode(trans, root, inode); + WARN_ON(ret); + + if (i_size_read(inode) > 0) { + ret = btrfs_truncate_free_space_cache(root, trans, path, + inode); + if (ret) + goto out_put; + } + + spin_lock(&block_group->lock); + if (block_group->cached != BTRFS_CACHE_FINISHED) { + spin_unlock(&block_group->lock); + goto out_put; + } + spin_unlock(&block_group->lock); + + num_pages = (int)div64_u64(block_group->key.offset, 1024 * 1024 * 1024); + if (!num_pages) + num_pages = 1; + + /* + * Just to make absolutely sure we have enough space, we're going to + * preallocate 12 pages worth of space for each block group. In + * practice we ought to use at most 8, but we need extra space so we can + * add our header and have a terminator between the extents and the + * bitmaps. + */ + num_pages *= 16; + num_pages *= PAGE_CACHE_SIZE; + + ret = btrfs_check_data_free_space(inode, num_pages); + if (ret) + goto out_put; + + ret = btrfs_prealloc_file_range_trans(inode, trans, 0, 0, num_pages, + num_pages, num_pages, + &alloc_hint); + btrfs_free_reserved_data_space(inode, num_pages); +out_put: + iput(inode); +out_free: + btrfs_release_path(root, path); +out: + spin_lock(&block_group->lock); + if (ret) + block_group->disk_cache_state = BTRFS_DC_ERROR; + else + block_group->disk_cache_state = BTRFS_DC_SETUP; + spin_unlock(&block_group->lock); + + return ret; +} + int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans, struct btrfs_root *root) { @@ -2700,6 +2803,25 @@ int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans, if (!path) return -ENOMEM; +again: + while (1) { + cache = btrfs_lookup_first_block_group(root->fs_info, last); + while (cache) { + if (cache->disk_cache_state == BTRFS_DC_CLEAR) + break; + cache = next_block_group(root, cache); + } + if (!cache) { + if (last == 0) + break; + last = 0; + continue; + } + err = cache_save_setup(cache, trans, path); + last = cache->key.objectid + cache->key.offset; + btrfs_put_block_group(cache); + } + while (1) { if (last == 0) { err = btrfs_run_delayed_refs(trans, root, @@ -2709,6 +2831,11 @@ int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans, cache = btrfs_lookup_first_block_group(root->fs_info, last); while (cache) { + if (cache->disk_cache_state == BTRFS_DC_CLEAR) { + btrfs_put_block_group(cache); + goto again; + } + if (cache->dirty) break; cache = next_block_group(root, cache); @@ -2883,11 +3010,16 @@ int btrfs_check_data_free_space(struct inode *inode, u64 bytes) struct btrfs_space_info *data_sinfo; struct btrfs_root *root = BTRFS_I(inode)->root; u64 used; - int ret = 0, committed = 0; + int ret = 0, committed = 0, alloc_chunk = 1; /* make sure bytes are sectorsize aligned */ bytes = (bytes + root->sectorsize - 1) & ~((u64)root->sectorsize - 1); + if (root == root->fs_info->tree_root) { + alloc_chunk = 0; + committed = 1; + } + data_sinfo = BTRFS_I(inode)->space_info; if (!data_sinfo) goto alloc; @@ -2906,7 +3038,7 @@ again: * if we don't have enough free bytes in this space then we need * to alloc a new chunk. */ - if (!data_sinfo->full) { + if (!data_sinfo->full && alloc_chunk) { u64 alloc_target; data_sinfo->force_alloc = 1; @@ -3777,12 +3909,12 @@ static int update_block_group(struct btrfs_trans_handle *trans, struct btrfs_root *root, u64 bytenr, u64 num_bytes, int alloc) { - struct btrfs_block_group_cache *cache; + struct btrfs_block_group_cache *cache = NULL; struct btrfs_fs_info *info = root->fs_info; - int factor; u64 total = num_bytes; u64 old_val; u64 byte_in_group; + int factor; /* block accounting for super block */ spin_lock(&info->delalloc_lock); @@ -3804,11 +3936,17 @@ static int update_block_group(struct btrfs_trans_handle *trans, factor = 2; else factor = 1; + byte_in_group = bytenr - cache->key.objectid; WARN_ON(byte_in_group > cache->key.offset); spin_lock(&cache->space_info->lock); spin_lock(&cache->lock); + + if (btrfs_super_cache_generation(&info->super_copy) != 0 && + cache->disk_cache_state < BTRFS_DC_CLEAR) + cache->disk_cache_state = BTRFS_DC_CLEAR; + cache->dirty = 1; old_val = btrfs_block_group_used(&cache->item); num_bytes = min(total, cache->key.offset - byte_in_group); @@ -7814,6 +7952,40 @@ out: return ret; } +void btrfs_put_block_group_cache(struct btrfs_fs_info *info) +{ + struct btrfs_block_group_cache *block_group; + u64 last = 0; + + while (1) { + struct inode *inode; + + block_group = btrfs_lookup_first_block_group(info, last); + while (block_group) { + spin_lock(&block_group->lock); + if (block_group->iref) + break; + spin_unlock(&block_group->lock); + block_group = next_block_group(info->tree_root, + block_group); + } + if (!block_group) { + if (last == 0) + break; + last = 0; + continue; + } + + inode = block_group->inode; + block_group->iref = 0; + block_group->inode = NULL; + spin_unlock(&block_group->lock); + iput(inode); + last = block_group->key.objectid + block_group->key.offset; + btrfs_put_block_group(block_group); + } +} + int btrfs_free_block_groups(struct btrfs_fs_info *info) { struct btrfs_block_group_cache *block_group; @@ -7897,6 +8069,8 @@ int btrfs_read_block_groups(struct btrfs_root *root) struct btrfs_key key; struct btrfs_key found_key; struct extent_buffer *leaf; + int need_clear = 0; + u64 cache_gen; root = info->extent_root; key.objectid = 0; @@ -7906,6 +8080,11 @@ int btrfs_read_block_groups(struct btrfs_root *root) if (!path) return -ENOMEM; + cache_gen = btrfs_super_cache_generation(&root->fs_info->super_copy); + if (cache_gen != 0 && + btrfs_super_generation(&root->fs_info->super_copy) != cache_gen) + need_clear = 1; + while (1) { ret = find_first_block_group(root, path, &key); if (ret > 0) @@ -7928,6 +8107,9 @@ int btrfs_read_block_groups(struct btrfs_root *root) INIT_LIST_HEAD(&cache->list); INIT_LIST_HEAD(&cache->cluster_list); + if (need_clear) + cache->disk_cache_state = BTRFS_DC_CLEAR; + /* * we only want to have 32k of ram per block group for keeping * track of free space, and if we pass 1/2 of that we want to @@ -8032,6 +8214,7 @@ int btrfs_make_block_group(struct btrfs_trans_handle *trans, cache->key.offset = size; cache->key.type = BTRFS_BLOCK_GROUP_ITEM_KEY; cache->sectorsize = root->sectorsize; + cache->fs_info = root->fs_info; /* * we only want to have 32k of ram per block group for keeping track @@ -8088,7 +8271,9 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans, struct btrfs_path *path; struct btrfs_block_group_cache *block_group; struct btrfs_free_cluster *cluster; + struct btrfs_root *tree_root = root->fs_info->tree_root; struct btrfs_key key; + struct inode *inode; int ret; root = root->fs_info->extent_root; @@ -8097,8 +8282,6 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans, BUG_ON(!block_group); BUG_ON(!block_group->ro); - memcpy(&key, &block_group->key, sizeof(key)); - /* make sure this block group isn't part of an allocation cluster */ cluster = &root->fs_info->data_alloc_cluster; spin_lock(&cluster->refill_lock); @@ -8117,6 +8300,40 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans, path = btrfs_alloc_path(); BUG_ON(!path); + inode = lookup_free_space_inode(root, block_group, path); + if (!IS_ERR(inode)) { + btrfs_orphan_add(trans, inode); + clear_nlink(inode); + /* One for the block groups ref */ + spin_lock(&block_group->lock); + if (block_group->iref) { + block_group->iref = 0; + block_group->inode = NULL; + spin_unlock(&block_group->lock); + iput(inode); + } else { + spin_unlock(&block_group->lock); + } + /* One for our lookup ref */ + iput(inode); + } + + key.objectid = BTRFS_FREE_SPACE_OBJECTID; + key.offset = block_group->key.objectid; + key.type = 0; + + ret = btrfs_search_slot(trans, tree_root, &key, path, -1, 1); + if (ret < 0) + goto out; + if (ret > 0) + btrfs_release_path(tree_root, path); + if (ret == 0) { + ret = btrfs_del_item(trans, tree_root, path); + if (ret) + goto out; + btrfs_release_path(tree_root, path); + } + spin_lock(&root->fs_info->block_group_cache_lock); rb_erase(&block_group->cache_node, &root->fs_info->block_group_cache_tree); @@ -8140,6 +8357,8 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans, block_group->space_info->bytes_readonly -= block_group->key.offset; spin_unlock(&block_group->space_info->lock); + memcpy(&key, &block_group->key, sizeof(key)); + btrfs_clear_space_info_full(root->fs_info); btrfs_put_block_group(block_group); diff --git a/fs/btrfs/free-space-cache.c b/fs/btrfs/free-space-cache.c index f488fac04d99..05efcc7061a7 100644 --- a/fs/btrfs/free-space-cache.c +++ b/fs/btrfs/free-space-cache.c @@ -23,10 +23,165 @@ #include "ctree.h" #include "free-space-cache.h" #include "transaction.h" +#include "disk-io.h" #define BITS_PER_BITMAP (PAGE_CACHE_SIZE * 8) #define MAX_CACHE_BYTES_PER_GIG (32 * 1024) +struct inode *lookup_free_space_inode(struct btrfs_root *root, + struct btrfs_block_group_cache + *block_group, struct btrfs_path *path) +{ + struct btrfs_key key; + struct btrfs_key location; + struct btrfs_disk_key disk_key; + struct btrfs_free_space_header *header; + struct extent_buffer *leaf; + struct inode *inode = NULL; + int ret; + + spin_lock(&block_group->lock); + if (block_group->inode) + inode = igrab(block_group->inode); + spin_unlock(&block_group->lock); + if (inode) + return inode; + + key.objectid = BTRFS_FREE_SPACE_OBJECTID; + key.offset = block_group->key.objectid; + key.type = 0; + + ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); + if (ret < 0) + return ERR_PTR(ret); + if (ret > 0) { + btrfs_release_path(root, path); + return ERR_PTR(-ENOENT); + } + + leaf = path->nodes[0]; + header = btrfs_item_ptr(leaf, path->slots[0], + struct btrfs_free_space_header); + btrfs_free_space_key(leaf, header, &disk_key); + btrfs_disk_key_to_cpu(&location, &disk_key); + btrfs_release_path(root, path); + + inode = btrfs_iget(root->fs_info->sb, &location, root, NULL); + if (!inode) + return ERR_PTR(-ENOENT); + if (IS_ERR(inode)) + return inode; + if (is_bad_inode(inode)) { + iput(inode); + return ERR_PTR(-ENOENT); + } + + spin_lock(&block_group->lock); + if (!root->fs_info->closing) { + block_group->inode = igrab(inode); + block_group->iref = 1; + } + spin_unlock(&block_group->lock); + + return inode; +} + +int create_free_space_inode(struct btrfs_root *root, + struct btrfs_trans_handle *trans, + struct btrfs_block_group_cache *block_group, + struct btrfs_path *path) +{ + struct btrfs_key key; + struct btrfs_disk_key disk_key; + struct btrfs_free_space_header *header; + struct btrfs_inode_item *inode_item; + struct extent_buffer *leaf; + u64 objectid; + int ret; + + ret = btrfs_find_free_objectid(trans, root, 0, &objectid); + if (ret < 0) + return ret; + + ret = btrfs_insert_empty_inode(trans, root, path, objectid); + if (ret) + return ret; + + leaf = path->nodes[0]; + inode_item = btrfs_item_ptr(leaf, path->slots[0], + struct btrfs_inode_item); + btrfs_item_key(leaf, &disk_key, path->slots[0]); + memset_extent_buffer(leaf, 0, (unsigned long)inode_item, + sizeof(*inode_item)); + btrfs_set_inode_generation(leaf, inode_item, trans->transid); + btrfs_set_inode_size(leaf, inode_item, 0); + btrfs_set_inode_nbytes(leaf, inode_item, 0); + btrfs_set_inode_uid(leaf, inode_item, 0); + btrfs_set_inode_gid(leaf, inode_item, 0); + btrfs_set_inode_mode(leaf, inode_item, S_IFREG | 0600); + btrfs_set_inode_flags(leaf, inode_item, BTRFS_INODE_NOCOMPRESS | + BTRFS_INODE_PREALLOC | BTRFS_INODE_NODATASUM); + btrfs_set_inode_nlink(leaf, inode_item, 1); + btrfs_set_inode_transid(leaf, inode_item, trans->transid); + btrfs_set_inode_block_group(leaf, inode_item, + block_group->key.objectid); + btrfs_mark_buffer_dirty(leaf); + btrfs_release_path(root, path); + + key.objectid = BTRFS_FREE_SPACE_OBJECTID; + key.offset = block_group->key.objectid; + key.type = 0; + + ret = btrfs_insert_empty_item(trans, root, path, &key, + sizeof(struct btrfs_free_space_header)); + if (ret < 0) { + btrfs_release_path(root, path); + return ret; + } + leaf = path->nodes[0]; + header = btrfs_item_ptr(leaf, path->slots[0], + struct btrfs_free_space_header); + memset_extent_buffer(leaf, 0, (unsigned long)header, sizeof(*header)); + btrfs_set_free_space_key(leaf, header, &disk_key); + btrfs_mark_buffer_dirty(leaf); + btrfs_release_path(root, path); + + return 0; +} + +int btrfs_truncate_free_space_cache(struct btrfs_root *root, + struct btrfs_trans_handle *trans, + struct btrfs_path *path, + struct inode *inode) +{ + loff_t oldsize; + int ret = 0; + + trans->block_rsv = root->orphan_block_rsv; + ret = btrfs_block_rsv_check(trans, root, + root->orphan_block_rsv, + 0, 5); + if (ret) + return ret; + + oldsize = i_size_read(inode); + btrfs_i_size_write(inode, 0); + truncate_pagecache(inode, oldsize, 0); + + /* + * We don't need an orphan item because truncating the free space cache + * will never be split across transactions. + */ + ret = btrfs_truncate_inode_items(trans, root, inode, + 0, BTRFS_EXTENT_DATA_KEY); + if (ret) { + WARN_ON(1); + return ret; + } + + return btrfs_update_inode(trans, root, inode); +} + static inline unsigned long offset_to_bit(u64 bitmap_start, u64 sectorsize, u64 offset) { diff --git a/fs/btrfs/free-space-cache.h b/fs/btrfs/free-space-cache.h index 890a8e79011b..45be29e5f01e 100644 --- a/fs/btrfs/free-space-cache.h +++ b/fs/btrfs/free-space-cache.h @@ -27,6 +27,17 @@ struct btrfs_free_space { struct list_head list; }; +struct inode *lookup_free_space_inode(struct btrfs_root *root, + struct btrfs_block_group_cache + *block_group, struct btrfs_path *path); +int create_free_space_inode(struct btrfs_root *root, + struct btrfs_trans_handle *trans, + struct btrfs_block_group_cache *block_group, + struct btrfs_path *path); +int btrfs_truncate_free_space_cache(struct btrfs_root *root, + struct btrfs_trans_handle *trans, + struct btrfs_path *path, + struct inode *inode); int btrfs_add_free_space(struct btrfs_block_group_cache *block_group, u64 bytenr, u64 size); int btrfs_remove_free_space(struct btrfs_block_group_cache *block_group, diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index c03864406af3..1af1ea88e8a8 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -1700,6 +1700,7 @@ static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end) ordered_extent->len); BUG_ON(ret); } else { + BUG_ON(root == root->fs_info->tree_root); ret = insert_reserved_file_extent(trans, inode, ordered_extent->file_offset, ordered_extent->start, @@ -3196,7 +3197,7 @@ int btrfs_truncate_inode_items(struct btrfs_trans_handle *trans, BUG_ON(new_size > 0 && min_type != BTRFS_EXTENT_DATA_KEY); - if (root->ref_cows) + if (root->ref_cows || root == root->fs_info->tree_root) btrfs_drop_extent_cache(inode, new_size & (~mask), (u64)-1, 0); path = btrfs_alloc_path(); @@ -3344,7 +3345,8 @@ delete: } else { break; } - if (found_extent && root->ref_cows) { + if (found_extent && (root->ref_cows || + root == root->fs_info->tree_root)) { btrfs_set_path_blocking(path); ret = btrfs_free_extent(trans, root, extent_start, extent_num_bytes, 0, @@ -3675,7 +3677,8 @@ void btrfs_evict_inode(struct inode *inode) int ret; truncate_inode_pages(&inode->i_data, 0); - if (inode->i_nlink && btrfs_root_refs(&root->root_item) != 0) + if (inode->i_nlink && (btrfs_root_refs(&root->root_item) != 0 || + root == root->fs_info->tree_root)) goto no_delete; if (is_bad_inode(inode)) { @@ -3888,7 +3891,14 @@ static void inode_tree_del(struct inode *inode) } spin_unlock(&root->inode_lock); - if (empty && btrfs_root_refs(&root->root_item) == 0) { + /* + * Free space cache has inodes in the tree root, but the tree root has a + * root_refs of 0, so this could end up dropping the tree root as a + * snapshot, so we need the extra !root->fs_info->tree_root check to + * make sure we don't drop it. + */ + if (empty && btrfs_root_refs(&root->root_item) == 0 && + root != root->fs_info->tree_root) { synchronize_srcu(&root->fs_info->subvol_srcu); spin_lock(&root->inode_lock); empty = RB_EMPTY_ROOT(&root->inode_tree); @@ -4282,14 +4292,24 @@ int btrfs_write_inode(struct inode *inode, struct writeback_control *wbc) struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_trans_handle *trans; int ret = 0; + bool nolock = false; if (BTRFS_I(inode)->dummy_inode) return 0; + smp_mb(); + nolock = (root->fs_info->closing && root == root->fs_info->tree_root); + if (wbc->sync_mode == WB_SYNC_ALL) { - trans = btrfs_join_transaction(root, 1); + if (nolock) + trans = btrfs_join_transaction_nolock(root, 1); + else + trans = btrfs_join_transaction(root, 1); btrfs_set_trans_block_group(trans, inode); - ret = btrfs_commit_transaction(trans, root); + if (nolock) + ret = btrfs_end_transaction_nolock(trans, root); + else + ret = btrfs_commit_transaction(trans, root); } return ret; } @@ -6308,6 +6328,21 @@ void btrfs_destroy_inode(struct inode *inode) spin_unlock(&root->fs_info->ordered_extent_lock); } + if (root == root->fs_info->tree_root) { + struct btrfs_block_group_cache *block_group; + + block_group = btrfs_lookup_block_group(root->fs_info, + BTRFS_I(inode)->block_group); + if (block_group && block_group->inode == inode) { + spin_lock(&block_group->lock); + block_group->inode = NULL; + spin_unlock(&block_group->lock); + btrfs_put_block_group(block_group); + } else if (block_group) { + btrfs_put_block_group(block_group); + } + } + spin_lock(&root->orphan_lock); if (!list_empty(&BTRFS_I(inode)->i_orphan)) { printk(KERN_INFO "BTRFS: inode %lu still on the orphan list\n", @@ -6340,7 +6375,8 @@ int btrfs_drop_inode(struct inode *inode) { struct btrfs_root *root = BTRFS_I(inode)->root; - if (btrfs_root_refs(&root->root_item) == 0) + if (btrfs_root_refs(&root->root_item) == 0 && + root != root->fs_info->tree_root) return 1; else return generic_drop_inode(inode); @@ -6757,27 +6793,33 @@ out_unlock: return err; } -int btrfs_prealloc_file_range(struct inode *inode, int mode, - u64 start, u64 num_bytes, u64 min_size, - loff_t actual_len, u64 *alloc_hint) +static int __btrfs_prealloc_file_range(struct inode *inode, int mode, + u64 start, u64 num_bytes, u64 min_size, + loff_t actual_len, u64 *alloc_hint, + struct btrfs_trans_handle *trans) { - struct btrfs_trans_handle *trans; struct btrfs_root *root = BTRFS_I(inode)->root; struct btrfs_key ins; u64 cur_offset = start; int ret = 0; + bool own_trans = true; + if (trans) + own_trans = false; while (num_bytes > 0) { - trans = btrfs_start_transaction(root, 3); - if (IS_ERR(trans)) { - ret = PTR_ERR(trans); - break; + if (own_trans) { + trans = btrfs_start_transaction(root, 3); + if (IS_ERR(trans)) { + ret = PTR_ERR(trans); + break; + } } ret = btrfs_reserve_extent(trans, root, num_bytes, min_size, 0, *alloc_hint, (u64)-1, &ins, 1); if (ret) { - btrfs_end_transaction(trans, root); + if (own_trans) + btrfs_end_transaction(trans, root); break; } @@ -6810,11 +6852,30 @@ int btrfs_prealloc_file_range(struct inode *inode, int mode, ret = btrfs_update_inode(trans, root, inode); BUG_ON(ret); - btrfs_end_transaction(trans, root); + if (own_trans) + btrfs_end_transaction(trans, root); } return ret; } +int btrfs_prealloc_file_range(struct inode *inode, int mode, + u64 start, u64 num_bytes, u64 min_size, + loff_t actual_len, u64 *alloc_hint) +{ + return __btrfs_prealloc_file_range(inode, mode, start, num_bytes, + min_size, actual_len, alloc_hint, + NULL); +} + +int btrfs_prealloc_file_range_trans(struct inode *inode, + struct btrfs_trans_handle *trans, int mode, + u64 start, u64 num_bytes, u64 min_size, + loff_t actual_len, u64 *alloc_hint) +{ + return __btrfs_prealloc_file_range(inode, mode, start, num_bytes, + min_size, actual_len, alloc_hint, trans); +} + static long btrfs_fallocate(struct inode *inode, int mode, loff_t offset, loff_t len) { diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c index b37d723b9d4a..af339eee55b8 100644 --- a/fs/btrfs/relocation.c +++ b/fs/btrfs/relocation.c @@ -29,6 +29,7 @@ #include "locking.h" #include "btrfs_inode.h" #include "async-thread.h" +#include "free-space-cache.h" /* * backref_node, mapping_node and tree_block start with this @@ -3191,6 +3192,54 @@ static int block_use_full_backref(struct reloc_control *rc, return ret; } +static int delete_block_group_cache(struct btrfs_fs_info *fs_info, + struct inode *inode, u64 ino) +{ + struct btrfs_key key; + struct btrfs_path *path; + struct btrfs_root *root = fs_info->tree_root; + struct btrfs_trans_handle *trans; + unsigned long nr; + int ret = 0; + + if (inode) + goto truncate; + + key.objectid = ino; + key.type = BTRFS_INODE_ITEM_KEY; + key.offset = 0; + + inode = btrfs_iget(fs_info->sb, &key, root, NULL); + if (!inode || IS_ERR(inode) || is_bad_inode(inode)) { + if (inode && !IS_ERR(inode)) + iput(inode); + return -ENOENT; + } + +truncate: + path = btrfs_alloc_path(); + if (!path) { + ret = -ENOMEM; + goto out; + } + + trans = btrfs_join_transaction(root, 0); + if (IS_ERR(trans)) { + btrfs_free_path(path); + goto out; + } + + ret = btrfs_truncate_free_space_cache(root, trans, path, inode); + + btrfs_free_path(path); + nr = trans->blocks_used; + btrfs_end_transaction(trans, root); + btrfs_btree_balance_dirty(root, nr); +out: + iput(inode); + return ret; +} + /* * helper to add tree blocks for backref of type BTRFS_EXTENT_DATA_REF_KEY * this function scans fs tree to find blocks reference the data extent @@ -3217,15 +3266,27 @@ static int find_data_references(struct reloc_control *rc, int counted; int ret; - path = btrfs_alloc_path(); - if (!path) - return -ENOMEM; - ref_root = btrfs_extent_data_ref_root(leaf, ref); ref_objectid = btrfs_extent_data_ref_objectid(leaf, ref); ref_offset = btrfs_extent_data_ref_offset(leaf, ref); ref_count = btrfs_extent_data_ref_count(leaf, ref); + /* + * This is an extent belonging to the free space cache, lets just delete + * it and redo the search. + */ + if (ref_root == BTRFS_ROOT_TREE_OBJECTID) { + ret = delete_block_group_cache(rc->extent_root->fs_info, + NULL, ref_objectid); + if (ret != -ENOENT) + return ret; + ret = 0; + } + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + root = read_fs_root(rc->extent_root->fs_info, ref_root); if (IS_ERR(root)) { err = PTR_ERR(root); @@ -3860,6 +3921,8 @@ int btrfs_relocate_block_group(struct btrfs_root *extent_root, u64 group_start) { struct btrfs_fs_info *fs_info = extent_root->fs_info; struct reloc_control *rc; + struct inode *inode; + struct btrfs_path *path; int ret; int rw = 0; int err = 0; @@ -3882,6 +3945,26 @@ int btrfs_relocate_block_group(struct btrfs_root *extent_root, u64 group_start) rw = 1; } + path = btrfs_alloc_path(); + if (!path) { + err = -ENOMEM; + goto out; + } + + inode = lookup_free_space_inode(fs_info->tree_root, rc->block_group, + path); + btrfs_free_path(path); + + if (!IS_ERR(inode)) + ret = delete_block_group_cache(fs_info, inode, 0); + else + ret = PTR_ERR(inode); + + if (ret && ret != -ENOENT) { + err = ret; + goto out; + } + rc->data_inode = create_reloc_inode(fs_info, rc->block_group); if (IS_ERR(rc->data_inode)) { err = PTR_ERR(rc->data_inode); diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index 1776dbd8dc98..5c23eb8d6ba3 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -68,7 +68,7 @@ enum { Opt_nodatacow, Opt_max_inline, Opt_alloc_start, Opt_nobarrier, Opt_ssd, Opt_nossd, Opt_ssd_spread, Opt_thread_pool, Opt_noacl, Opt_compress, Opt_compress_force, Opt_notreelog, Opt_ratio, Opt_flushoncommit, - Opt_discard, Opt_err, + Opt_discard, Opt_space_cache, Opt_err, }; static match_table_t tokens = { @@ -92,6 +92,7 @@ static match_table_t tokens = { {Opt_flushoncommit, "flushoncommit"}, {Opt_ratio, "metadata_ratio=%d"}, {Opt_discard, "discard"}, + {Opt_space_cache, "space_cache"}, {Opt_err, NULL}, }; @@ -235,6 +236,10 @@ int btrfs_parse_options(struct btrfs_root *root, char *options) case Opt_discard: btrfs_set_opt(info->mount_opt, DISCARD); break; + case Opt_space_cache: + printk(KERN_INFO "btrfs: enabling disk space caching\n"); + btrfs_set_opt(info->mount_opt, SPACE_CACHE); + break; case Opt_err: printk(KERN_INFO "btrfs: unrecognized mount option " "'%s'\n", p); diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c index 66e4c66cc63b..e7144c48ed79 100644 --- a/fs/btrfs/transaction.c +++ b/fs/btrfs/transaction.c @@ -163,6 +163,7 @@ enum btrfs_trans_type { TRANS_START, TRANS_JOIN, TRANS_USERSPACE, + TRANS_JOIN_NOLOCK, }; static int may_wait_transaction(struct btrfs_root *root, int type) @@ -186,7 +187,8 @@ again: if (!h) return ERR_PTR(-ENOMEM); - mutex_lock(&root->fs_info->trans_mutex); + if (type != TRANS_JOIN_NOLOCK) + mutex_lock(&root->fs_info->trans_mutex); if (may_wait_transaction(root, type)) wait_current_trans(root); @@ -195,7 +197,8 @@ again: cur_trans = root->fs_info->running_transaction; cur_trans->use_count++; - mutex_unlock(&root->fs_info->trans_mutex); + if (type != TRANS_JOIN_NOLOCK) + mutex_unlock(&root->fs_info->trans_mutex); h->transid = cur_trans->transid; h->transaction = cur_trans; @@ -224,9 +227,11 @@ again: } } - mutex_lock(&root->fs_info->trans_mutex); + if (type != TRANS_JOIN_NOLOCK) + mutex_lock(&root->fs_info->trans_mutex); record_root_in_trans(h, root); - mutex_unlock(&root->fs_info->trans_mutex); + if (type != TRANS_JOIN_NOLOCK) + mutex_unlock(&root->fs_info->trans_mutex); if (!current->journal_info && type != TRANS_USERSPACE) current->journal_info = h; @@ -244,6 +249,12 @@ struct btrfs_trans_handle *btrfs_join_transaction(struct btrfs_root *root, return start_transaction(root, 0, TRANS_JOIN); } +struct btrfs_trans_handle *btrfs_join_transaction_nolock(struct btrfs_root *root, + int num_blocks) +{ + return start_transaction(root, 0, TRANS_JOIN_NOLOCK); +} + struct btrfs_trans_handle *btrfs_start_ioctl_transaction(struct btrfs_root *r, int num_blocks) { @@ -348,7 +359,7 @@ int btrfs_should_end_transaction(struct btrfs_trans_handle *trans, } static int __btrfs_end_transaction(struct btrfs_trans_handle *trans, - struct btrfs_root *root, int throttle) + struct btrfs_root *root, int throttle, int lock) { struct btrfs_transaction *cur_trans = trans->transaction; struct btrfs_fs_info *info = root->fs_info; @@ -376,18 +387,19 @@ static int __btrfs_end_transaction(struct btrfs_trans_handle *trans, btrfs_trans_release_metadata(trans, root); - if (!root->fs_info->open_ioctl_trans && + if (lock && !root->fs_info->open_ioctl_trans && should_end_transaction(trans, root)) trans->transaction->blocked = 1; - if (cur_trans->blocked && !cur_trans->in_commit) { + if (lock && cur_trans->blocked && !cur_trans->in_commit) { if (throttle) return btrfs_commit_transaction(trans, root); else wake_up_process(info->transaction_kthread); } - mutex_lock(&info->trans_mutex); + if (lock) + mutex_lock(&info->trans_mutex); WARN_ON(cur_trans != info->running_transaction); WARN_ON(cur_trans->num_writers < 1); cur_trans->num_writers--; @@ -395,7 +407,8 @@ static int __btrfs_end_transaction(struct btrfs_trans_handle *trans, if (waitqueue_active(&cur_trans->writer_wait)) wake_up(&cur_trans->writer_wait); put_transaction(cur_trans); - mutex_unlock(&info->trans_mutex); + if (lock) + mutex_unlock(&info->trans_mutex); if (current->journal_info == trans) current->journal_info = NULL; @@ -411,13 +424,19 @@ static int __btrfs_end_transaction(struct btrfs_trans_handle *trans, int btrfs_end_transaction(struct btrfs_trans_handle *trans, struct btrfs_root *root) { - return __btrfs_end_transaction(trans, root, 0); + return __btrfs_end_transaction(trans, root, 0, 1); } int btrfs_end_transaction_throttle(struct btrfs_trans_handle *trans, struct btrfs_root *root) { - return __btrfs_end_transaction(trans, root, 1); + return __btrfs_end_transaction(trans, root, 1, 1); +} + +int btrfs_end_transaction_nolock(struct btrfs_trans_handle *trans, + struct btrfs_root *root) +{ + return __btrfs_end_transaction(trans, root, 0, 0); } /* @@ -966,6 +985,8 @@ static void update_super_roots(struct btrfs_root *root) super->root = root_item->bytenr; super->generation = root_item->generation; super->root_level = root_item->level; + if (super->cache_generation != 0 || btrfs_test_opt(root, SPACE_CACHE)) + super->cache_generation = root_item->generation; } int btrfs_transaction_in_commit(struct btrfs_fs_info *info) diff --git a/fs/btrfs/transaction.h b/fs/btrfs/transaction.h index e104986d0bfd..15f83e1c1ef7 100644 --- a/fs/btrfs/transaction.h +++ b/fs/btrfs/transaction.h @@ -87,10 +87,14 @@ static inline void btrfs_set_inode_last_trans(struct btrfs_trans_handle *trans, int btrfs_end_transaction(struct btrfs_trans_handle *trans, struct btrfs_root *root); +int btrfs_end_transaction_nolock(struct btrfs_trans_handle *trans, + struct btrfs_root *root); struct btrfs_trans_handle *btrfs_start_transaction(struct btrfs_root *root, int num_items); struct btrfs_trans_handle *btrfs_join_transaction(struct btrfs_root *root, int num_blocks); +struct btrfs_trans_handle *btrfs_join_transaction_nolock(struct btrfs_root *root, + int num_blocks); struct btrfs_trans_handle *btrfs_start_ioctl_transaction(struct btrfs_root *r, int num_blocks); int btrfs_write_and_wait_transaction(struct btrfs_trans_handle *trans, -- 2.20.1