diff --git a/fs/btrfs/Makefile b/fs/btrfs/Makefile index 6d1d0b93b1aa..128ce17a80b0 100644 --- a/fs/btrfs/Makefile +++ b/fs/btrfs/Makefile @@ -9,11 +9,12 @@ btrfs-y += super.o ctree.o extent-tree.o print-tree.o root-tree.o dir-item.o \ export.o tree-log.o free-space-cache.o zlib.o lzo.o \ compression.o delayed-ref.o relocation.o delayed-inode.o scrub.o \ reada.o backref.o ulist.o qgroup.o send.o dev-replace.o raid56.o \ - uuid-tree.o props.o hash.o + uuid-tree.o props.o hash.o free-space-tree.o btrfs-$(CONFIG_BTRFS_FS_POSIX_ACL) += acl.o btrfs-$(CONFIG_BTRFS_FS_CHECK_INTEGRITY) += check-integrity.o btrfs-$(CONFIG_BTRFS_FS_RUN_SANITY_TESTS) += tests/free-space-tests.o \ tests/extent-buffer-tests.o tests/btrfs-tests.o \ - tests/extent-io-tests.o tests/inode-tests.o tests/qgroup-tests.o + tests/extent-io-tests.o tests/inode-tests.o tests/qgroup-tests.o \ + tests/free-space-tree-tests.o diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h index d8d3dd468d6d..d79ba0570c55 100644 --- a/fs/btrfs/ctree.h +++ b/fs/btrfs/ctree.h @@ -96,6 +96,9 @@ struct btrfs_ordered_sum; /* for storing items that use the BTRFS_UUID_KEY* types */ #define BTRFS_UUID_TREE_OBJECTID 9ULL +/* tracks free space in block groups. */ +#define BTRFS_FREE_SPACE_TREE_OBJECTID 10ULL + /* for storing balance parameters in the root tree */ #define BTRFS_BALANCE_OBJECTID -4ULL @@ -500,6 +503,8 @@ struct btrfs_super_block { * Compat flags that we support. If any incompat flags are set other than the * ones specified below then we will fail to mount */ +#define BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE (1ULL << 0) + #define BTRFS_FEATURE_INCOMPAT_MIXED_BACKREF (1ULL << 0) #define BTRFS_FEATURE_INCOMPAT_DEFAULT_SUBVOL (1ULL << 1) #define BTRFS_FEATURE_INCOMPAT_MIXED_GROUPS (1ULL << 2) @@ -526,7 +531,10 @@ struct btrfs_super_block { #define BTRFS_FEATURE_COMPAT_SUPP 0ULL #define BTRFS_FEATURE_COMPAT_SAFE_SET 0ULL #define BTRFS_FEATURE_COMPAT_SAFE_CLEAR 0ULL -#define BTRFS_FEATURE_COMPAT_RO_SUPP 0ULL + +#define BTRFS_FEATURE_COMPAT_RO_SUPP \ + (BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE) + #define BTRFS_FEATURE_COMPAT_RO_SAFE_SET 0ULL #define BTRFS_FEATURE_COMPAT_RO_SAFE_CLEAR 0ULL @@ -1088,6 +1096,13 @@ struct btrfs_block_group_item { __le64 flags; } __attribute__ ((__packed__)); +struct btrfs_free_space_info { + __le32 extent_count; + __le32 flags; +} __attribute__ ((__packed__)); + +#define BTRFS_FREE_SPACE_USING_BITMAPS (1ULL << 0) + #define BTRFS_QGROUP_LEVEL_SHIFT 48 static inline u64 btrfs_qgroup_level(u64 qgroupid) { @@ -1296,6 +1311,9 @@ struct btrfs_caching_control { atomic_t count; }; +/* Once caching_thread() finds this much free space, it will wake up waiters. */ +#define CACHING_CTL_WAKE_UP (1024 * 1024 * 2) + struct btrfs_io_ctl { void *cur, *orig; struct page *page; @@ -1321,8 +1339,20 @@ struct btrfs_block_group_cache { u64 delalloc_bytes; u64 bytes_super; u64 flags; - u64 sectorsize; u64 cache_generation; + u32 sectorsize; + + /* + * If the free space extent count exceeds this number, convert the block + * group to bitmaps. + */ + u32 bitmap_high_thresh; + + /* + * If the free space extent count drops below this number, convert the + * block group back to extents. + */ + u32 bitmap_low_thresh; /* * It is just used for the delayed data space allocation because @@ -1378,6 +1408,15 @@ struct btrfs_block_group_cache { struct list_head io_list; struct btrfs_io_ctl io_ctl; + + /* Lock for free space tree operations. */ + struct mutex free_space_lock; + + /* + * Does the block group need to be added to the free space tree? + * Protected by free_space_lock. + */ + int needs_free_space; }; /* delayed seq elem */ @@ -1429,6 +1468,7 @@ struct btrfs_fs_info { struct btrfs_root *csum_root; struct btrfs_root *quota_root; struct btrfs_root *uuid_root; + struct btrfs_root *free_space_root; /* the log root tree is a directory of all the other log roots */ struct btrfs_root *log_root_tree; @@ -2092,6 +2132,27 @@ struct btrfs_ioctl_defrag_range_args { */ #define BTRFS_BLOCK_GROUP_ITEM_KEY 192 +/* + * Every block group is represented in the free space tree by a free space info + * item, which stores some accounting information. It is keyed on + * (block_group_start, FREE_SPACE_INFO, block_group_length). + */ +#define BTRFS_FREE_SPACE_INFO_KEY 198 + +/* + * A free space extent tracks an extent of space that is free in a block group. + * It is keyed on (start, FREE_SPACE_EXTENT, length). + */ +#define BTRFS_FREE_SPACE_EXTENT_KEY 199 + +/* + * When a block group becomes very fragmented, we convert it to use bitmaps + * instead of extents. A free space bitmap is keyed on + * (start, FREE_SPACE_BITMAP, length); the corresponding item is a bitmap with + * (length / sectorsize) bits. + */ +#define BTRFS_FREE_SPACE_BITMAP_KEY 200 + #define BTRFS_DEV_EXTENT_KEY 204 #define BTRFS_DEV_ITEM_KEY 216 #define BTRFS_CHUNK_ITEM_KEY 228 @@ -2184,6 +2245,7 @@ struct btrfs_ioctl_defrag_range_args { #define BTRFS_MOUNT_RESCAN_UUID_TREE (1 << 23) #define BTRFS_MOUNT_FRAGMENT_DATA (1 << 24) #define BTRFS_MOUNT_FRAGMENT_METADATA (1 << 25) +#define BTRFS_MOUNT_FREE_SPACE_TREE (1 << 26) #define BTRFS_DEFAULT_COMMIT_INTERVAL (30) #define BTRFS_DEFAULT_MAX_INLINE (8192) @@ -2506,6 +2568,11 @@ BTRFS_SETGET_FUNCS(disk_block_group_flags, BTRFS_SETGET_STACK_FUNCS(block_group_flags, struct btrfs_block_group_item, flags, 64); +/* struct btrfs_free_space_info */ +BTRFS_SETGET_FUNCS(free_space_extent_count, struct btrfs_free_space_info, + extent_count, 32); +BTRFS_SETGET_FUNCS(free_space_flags, struct btrfs_free_space_info, flags, 32); + /* struct btrfs_inode_ref */ BTRFS_SETGET_FUNCS(inode_ref_name_len, struct btrfs_inode_ref, name_len, 16); BTRFS_SETGET_FUNCS(inode_ref_index, struct btrfs_inode_ref, index, 64); @@ -3573,6 +3640,9 @@ void btrfs_end_write_no_snapshoting(struct btrfs_root *root); void check_system_chunk(struct btrfs_trans_handle *trans, struct btrfs_root *root, const u64 type); +u64 add_new_free_space(struct btrfs_block_group_cache *block_group, + struct btrfs_fs_info *info, u64 start, u64 end); + /* ctree.c */ int btrfs_bin_search(struct extent_buffer *eb, struct btrfs_key *key, int level, int *slot); @@ -3737,6 +3807,7 @@ static inline void free_fs_info(struct btrfs_fs_info *fs_info) kfree(fs_info->csum_root); kfree(fs_info->quota_root); kfree(fs_info->uuid_root); + kfree(fs_info->free_space_root); kfree(fs_info->super_copy); kfree(fs_info->super_for_commit); security_free_mnt_opts(&fs_info->security_opts); @@ -4246,6 +4317,30 @@ static inline void __btrfs_set_fs_incompat(struct btrfs_fs_info *fs_info, } } +#define btrfs_clear_fs_incompat(__fs_info, opt) \ + __btrfs_clear_fs_incompat((__fs_info), BTRFS_FEATURE_INCOMPAT_##opt) + +static inline void __btrfs_clear_fs_incompat(struct btrfs_fs_info *fs_info, + u64 flag) +{ + struct btrfs_super_block *disk_super; + u64 features; + + disk_super = fs_info->super_copy; + features = btrfs_super_incompat_flags(disk_super); + if (features & flag) { + spin_lock(&fs_info->super_lock); + features = btrfs_super_incompat_flags(disk_super); + if (features & flag) { + features &= ~flag; + btrfs_set_super_incompat_flags(disk_super, features); + btrfs_info(fs_info, "clearing %llu feature flag", + flag); + } + spin_unlock(&fs_info->super_lock); + } +} + #define btrfs_fs_incompat(fs_info, opt) \ __btrfs_fs_incompat((fs_info), BTRFS_FEATURE_INCOMPAT_##opt) @@ -4256,6 +4351,64 @@ static inline int __btrfs_fs_incompat(struct btrfs_fs_info *fs_info, u64 flag) return !!(btrfs_super_incompat_flags(disk_super) & flag); } +#define btrfs_set_fs_compat_ro(__fs_info, opt) \ + __btrfs_set_fs_compat_ro((__fs_info), BTRFS_FEATURE_COMPAT_RO_##opt) + +static inline void __btrfs_set_fs_compat_ro(struct btrfs_fs_info *fs_info, + u64 flag) +{ + struct btrfs_super_block *disk_super; + u64 features; + + disk_super = fs_info->super_copy; + features = btrfs_super_compat_ro_flags(disk_super); + if (!(features & flag)) { + spin_lock(&fs_info->super_lock); + features = btrfs_super_compat_ro_flags(disk_super); + if (!(features & flag)) { + features |= flag; + btrfs_set_super_compat_ro_flags(disk_super, features); + btrfs_info(fs_info, "setting %llu ro feature flag", + flag); + } + spin_unlock(&fs_info->super_lock); + } +} + +#define btrfs_clear_fs_compat_ro(__fs_info, opt) \ + __btrfs_clear_fs_compat_ro((__fs_info), BTRFS_FEATURE_COMPAT_RO_##opt) + +static inline void __btrfs_clear_fs_compat_ro(struct btrfs_fs_info *fs_info, + u64 flag) +{ + struct btrfs_super_block *disk_super; + u64 features; + + disk_super = fs_info->super_copy; + features = btrfs_super_compat_ro_flags(disk_super); + if (features & flag) { + spin_lock(&fs_info->super_lock); + features = btrfs_super_compat_ro_flags(disk_super); + if (features & flag) { + features &= ~flag; + btrfs_set_super_compat_ro_flags(disk_super, features); + btrfs_info(fs_info, "clearing %llu ro feature flag", + flag); + } + spin_unlock(&fs_info->super_lock); + } +} + +#define btrfs_fs_compat_ro(fs_info, opt) \ + __btrfs_fs_compat_ro((fs_info), BTRFS_FEATURE_COMPAT_RO_##opt) + +static inline int __btrfs_fs_compat_ro(struct btrfs_fs_info *fs_info, u64 flag) +{ + struct btrfs_super_block *disk_super; + disk_super = fs_info->super_copy; + return !!(btrfs_super_compat_ro_flags(disk_super) & flag); +} + /* * Call btrfs_abort_transaction as early as possible when an error condition is * detected, that way the exact line number is reported. diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c index 843dbd7e8422..823c1ce87e2e 100644 --- a/fs/btrfs/disk-io.c +++ b/fs/btrfs/disk-io.c @@ -42,6 +42,7 @@ #include "locking.h" #include "tree-log.h" #include "free-space-cache.h" +#include "free-space-tree.h" #include "inode-map.h" #include "check-integrity.h" #include "rcu-string.h" @@ -1650,6 +1651,9 @@ struct btrfs_root *btrfs_get_fs_root(struct btrfs_fs_info *fs_info, if (location->objectid == BTRFS_UUID_TREE_OBJECTID) return fs_info->uuid_root ? fs_info->uuid_root : ERR_PTR(-ENOENT); + if (location->objectid == BTRFS_FREE_SPACE_TREE_OBJECTID) + return fs_info->free_space_root ? fs_info->free_space_root : + ERR_PTR(-ENOENT); again: root = btrfs_lookup_fs_root(fs_info, location->objectid); if (root) { @@ -2148,6 +2152,7 @@ static void free_root_pointers(struct btrfs_fs_info *info, int chunk_root) free_root_extent_buffers(info->uuid_root); if (chunk_root) free_root_extent_buffers(info->chunk_root); + free_root_extent_buffers(info->free_space_root); } void btrfs_free_fs_roots(struct btrfs_fs_info *fs_info) @@ -2448,6 +2453,15 @@ static int btrfs_read_roots(struct btrfs_fs_info *fs_info, fs_info->uuid_root = root; } + if (btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) { + location.objectid = BTRFS_FREE_SPACE_TREE_OBJECTID; + root = btrfs_read_tree_root(tree_root, &location); + if (IS_ERR(root)) + return PTR_ERR(root); + set_bit(BTRFS_ROOT_TRACK_DIRTY, &root->state); + fs_info->free_space_root = root; + } + return 0; } @@ -3076,6 +3090,30 @@ retry_root_backup: btrfs_qgroup_rescan_resume(fs_info); + if (btrfs_test_opt(tree_root, CLEAR_CACHE) && + btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) { + pr_info("BTRFS: clearing free space tree\n"); + ret = btrfs_clear_free_space_tree(fs_info); + if (ret) { + pr_warn("BTRFS: failed to clear free space tree %d\n", + ret); + close_ctree(tree_root); + return ret; + } + } + + if (btrfs_test_opt(tree_root, FREE_SPACE_TREE) && + !btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) { + pr_info("BTRFS: creating free space tree\n"); + ret = btrfs_create_free_space_tree(fs_info); + if (ret) { + pr_warn("BTRFS: failed to create free space tree %d\n", + ret); + close_ctree(tree_root); + return ret; + } + } + if (!fs_info->uuid_root) { pr_info("BTRFS: creating UUID tree\n"); ret = btrfs_create_uuid_tree(fs_info); diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index d436117e20dd..0617cb73669d 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -33,6 +33,7 @@ #include "raid56.h" #include "locking.h" #include "free-space-cache.h" +#include "free-space-tree.h" #include "math.h" #include "sysfs.h" #include "qgroup.h" @@ -357,8 +358,8 @@ static void fragment_free_space(struct btrfs_root *root, * we need to check the pinned_extents for any extents that can't be used yet * since their free space will be released as soon as the transaction commits. */ -static u64 add_new_free_space(struct btrfs_block_group_cache *block_group, - struct btrfs_fs_info *info, u64 start, u64 end) +u64 add_new_free_space(struct btrfs_block_group_cache *block_group, + struct btrfs_fs_info *info, u64 start, u64 end) { u64 extent_start, extent_end, size, total_added = 0; int ret; @@ -395,11 +396,10 @@ static u64 add_new_free_space(struct btrfs_block_group_cache *block_group, return total_added; } -static noinline void caching_thread(struct btrfs_work *work) +static int load_extent_tree_free(struct btrfs_caching_control *caching_ctl) { struct btrfs_block_group_cache *block_group; struct btrfs_fs_info *fs_info; - struct btrfs_caching_control *caching_ctl; struct btrfs_root *extent_root; struct btrfs_path *path; struct extent_buffer *leaf; @@ -407,17 +407,16 @@ static noinline void caching_thread(struct btrfs_work *work) u64 total_found = 0; u64 last = 0; u32 nritems; - int ret = -ENOMEM; + int ret; bool wakeup = true; - caching_ctl = container_of(work, struct btrfs_caching_control, work); block_group = caching_ctl->block_group; fs_info = block_group->fs_info; extent_root = fs_info->extent_root; path = btrfs_alloc_path(); if (!path) - goto out; + return -ENOMEM; last = max_t(u64, block_group->key.objectid, BTRFS_SUPER_INFO_OFFSET); @@ -443,15 +442,11 @@ static noinline void caching_thread(struct btrfs_work *work) key.objectid = last; key.offset = 0; key.type = BTRFS_EXTENT_ITEM_KEY; -again: - mutex_lock(&caching_ctl->mutex); - /* need to make sure the commit_root doesn't disappear */ - down_read(&fs_info->commit_root_sem); next: ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0); if (ret < 0) - goto err; + goto out; leaf = path->nodes[0]; nritems = btrfs_header_nritems(leaf); @@ -477,12 +472,14 @@ next: up_read(&fs_info->commit_root_sem); mutex_unlock(&caching_ctl->mutex); cond_resched(); - goto again; + mutex_lock(&caching_ctl->mutex); + down_read(&fs_info->commit_root_sem); + goto next; } ret = btrfs_next_leaf(extent_root, path); if (ret < 0) - goto err; + goto out; if (ret) break; leaf = path->nodes[0]; @@ -521,7 +518,7 @@ next: else last = key.objectid + key.offset; - if (total_found > (1024 * 1024 * 2)) { + if (total_found > CACHING_CTL_WAKE_UP) { total_found = 0; if (wakeup) wake_up(&caching_ctl->wait); @@ -534,9 +531,35 @@ next: total_found += add_new_free_space(block_group, fs_info, last, block_group->key.objectid + block_group->key.offset); + caching_ctl->progress = (u64)-1; + +out: + btrfs_free_path(path); + return ret; +} + +static noinline void caching_thread(struct btrfs_work *work) +{ + struct btrfs_block_group_cache *block_group; + struct btrfs_fs_info *fs_info; + struct btrfs_caching_control *caching_ctl; + int ret; + + caching_ctl = container_of(work, struct btrfs_caching_control, work); + block_group = caching_ctl->block_group; + fs_info = block_group->fs_info; + + mutex_lock(&caching_ctl->mutex); + down_read(&fs_info->commit_root_sem); + + if (btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) + ret = load_free_space_tree(caching_ctl); + else + ret = load_extent_tree_free(caching_ctl); + spin_lock(&block_group->lock); block_group->caching_ctl = NULL; - block_group->cached = BTRFS_CACHE_FINISHED; + block_group->cached = ret ? BTRFS_CACHE_ERROR : BTRFS_CACHE_FINISHED; spin_unlock(&block_group->lock); #ifdef CONFIG_BTRFS_DEBUG @@ -555,20 +578,11 @@ next: #endif caching_ctl->progress = (u64)-1; -err: - btrfs_free_path(path); + up_read(&fs_info->commit_root_sem); - - free_excluded_extents(extent_root, block_group); - + free_excluded_extents(fs_info->extent_root, block_group); mutex_unlock(&caching_ctl->mutex); -out: - if (ret) { - spin_lock(&block_group->lock); - block_group->caching_ctl = NULL; - block_group->cached = BTRFS_CACHE_ERROR; - spin_unlock(&block_group->lock); - } + wake_up(&caching_ctl->wait); put_caching_control(caching_ctl); @@ -680,8 +694,8 @@ static int cache_block_group(struct btrfs_block_group_cache *cache, } } else { /* - * We are not going to do the fast caching, set cached to the - * appropriate value and wakeup any waiters. + * We're either using the free space tree or no caching at all. + * Set cached to the appropriate value and wakeup any waiters. */ spin_lock(&cache->lock); if (load_cache_only) { @@ -6676,6 +6690,13 @@ static int __btrfs_free_extent(struct btrfs_trans_handle *trans, } } + ret = add_to_free_space_tree(trans, root->fs_info, bytenr, + num_bytes); + if (ret) { + btrfs_abort_transaction(trans, extent_root, ret); + goto out; + } + ret = update_block_group(trans, root, bytenr, num_bytes, 0); if (ret) { btrfs_abort_transaction(trans, extent_root, ret); @@ -7687,6 +7708,11 @@ static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans, btrfs_mark_buffer_dirty(path->nodes[0]); btrfs_free_path(path); + ret = remove_from_free_space_tree(trans, fs_info, ins->objectid, + ins->offset); + if (ret) + return ret; + ret = update_block_group(trans, root, ins->objectid, ins->offset, 1); if (ret) { /* -ENOENT, logic error */ btrfs_err(fs_info, "update block group failed for %llu %llu", @@ -7767,6 +7793,11 @@ static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans, btrfs_mark_buffer_dirty(leaf); btrfs_free_path(path); + ret = remove_from_free_space_tree(trans, fs_info, ins->objectid, + num_bytes); + if (ret) + return ret; + ret = update_block_group(trans, root, ins->objectid, root->nodesize, 1); if (ret) { /* -ENOENT, logic error */ @@ -9671,6 +9702,8 @@ btrfs_create_block_group_cache(struct btrfs_root *root, u64 start, u64 size) cache->full_stripe_len = btrfs_full_stripe_len(root, &root->fs_info->mapping_tree, start); + set_free_space_tree_thresholds(cache); + atomic_set(&cache->count, 1); spin_lock_init(&cache->lock); init_rwsem(&cache->data_rwsem); @@ -9682,6 +9715,7 @@ btrfs_create_block_group_cache(struct btrfs_root *root, u64 start, u64 size) INIT_LIST_HEAD(&cache->io_list); btrfs_init_free_space_ctl(cache); atomic_set(&cache->trimming, 0); + mutex_init(&cache->free_space_lock); return cache; } @@ -9892,6 +9926,8 @@ void btrfs_create_pending_block_groups(struct btrfs_trans_handle *trans, key.objectid, key.offset); if (ret) btrfs_abort_transaction(trans, extent_root, ret); + add_block_group_free_space(trans, root->fs_info, block_group); + /* already aborted the transaction if it failed. */ next: list_del_init(&block_group->bg_list); } @@ -9922,6 +9958,7 @@ int btrfs_make_block_group(struct btrfs_trans_handle *trans, cache->flags = type; cache->last_byte_to_unpin = (u64)-1; cache->cached = BTRFS_CACHE_FINISHED; + cache->needs_free_space = 1; ret = exclude_super_stripes(root, cache); if (ret) { /* @@ -10292,6 +10329,10 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans, unlock_chunks(root); + ret = remove_block_group_free_space(trans, root->fs_info, block_group); + if (ret) + goto out; + btrfs_put_block_group(block_group); btrfs_put_block_group(block_group); diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c index 4d62b8230a64..a2356e261531 100644 --- a/fs/btrfs/extent_io.c +++ b/fs/btrfs/extent_io.c @@ -4702,24 +4702,14 @@ struct extent_buffer *btrfs_clone_extent_buffer(struct extent_buffer *src) return new; } -struct extent_buffer *alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info, - u64 start) +struct extent_buffer *__alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info, + u64 start, unsigned long len) { struct extent_buffer *eb; - unsigned long len; unsigned long num_pages; unsigned long i; - if (!fs_info) { - /* - * Called only from tests that don't always have a fs_info - * available, but we know that nodesize is 4096 - */ - len = 4096; - } else { - len = fs_info->tree_root->nodesize; - } - num_pages = num_extent_pages(0, len); + num_pages = num_extent_pages(start, len); eb = __alloc_extent_buffer(fs_info, start, len); if (!eb) @@ -4742,6 +4732,24 @@ err: return NULL; } +struct extent_buffer *alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info, + u64 start) +{ + unsigned long len; + + if (!fs_info) { + /* + * Called only from tests that don't always have a fs_info + * available, but we know that nodesize is 4096 + */ + len = 4096; + } else { + len = fs_info->tree_root->nodesize; + } + + return __alloc_dummy_extent_buffer(fs_info, start, len); +} + static void check_buffer_tree_ref(struct extent_buffer *eb) { int refs; @@ -5497,6 +5505,155 @@ void copy_extent_buffer(struct extent_buffer *dst, struct extent_buffer *src, } } +/* + * The extent buffer bitmap operations are done with byte granularity because + * bitmap items are not guaranteed to be aligned to a word and therefore a + * single word in a bitmap may straddle two pages in the extent buffer. + */ +#define BIT_BYTE(nr) ((nr) / BITS_PER_BYTE) +#define BYTE_MASK ((1 << BITS_PER_BYTE) - 1) +#define BITMAP_FIRST_BYTE_MASK(start) \ + ((BYTE_MASK << ((start) & (BITS_PER_BYTE - 1))) & BYTE_MASK) +#define BITMAP_LAST_BYTE_MASK(nbits) \ + (BYTE_MASK >> (-(nbits) & (BITS_PER_BYTE - 1))) + +/* + * eb_bitmap_offset() - calculate the page and offset of the byte containing the + * given bit number + * @eb: the extent buffer + * @start: offset of the bitmap item in the extent buffer + * @nr: bit number + * @page_index: return index of the page in the extent buffer that contains the + * given bit number + * @page_offset: return offset into the page given by page_index + * + * This helper hides the ugliness of finding the byte in an extent buffer which + * contains a given bit. + */ +static inline void eb_bitmap_offset(struct extent_buffer *eb, + unsigned long start, unsigned long nr, + unsigned long *page_index, + size_t *page_offset) +{ + size_t start_offset = eb->start & ((u64)PAGE_CACHE_SIZE - 1); + size_t byte_offset = BIT_BYTE(nr); + size_t offset; + + /* + * The byte we want is the offset of the extent buffer + the offset of + * the bitmap item in the extent buffer + the offset of the byte in the + * bitmap item. + */ + offset = start_offset + start + byte_offset; + + *page_index = offset >> PAGE_CACHE_SHIFT; + *page_offset = offset & (PAGE_CACHE_SIZE - 1); +} + +/** + * extent_buffer_test_bit - determine whether a bit in a bitmap item is set + * @eb: the extent buffer + * @start: offset of the bitmap item in the extent buffer + * @nr: bit number to test + */ +int extent_buffer_test_bit(struct extent_buffer *eb, unsigned long start, + unsigned long nr) +{ + char *kaddr; + struct page *page; + unsigned long i; + size_t offset; + + eb_bitmap_offset(eb, start, nr, &i, &offset); + page = eb->pages[i]; + WARN_ON(!PageUptodate(page)); + kaddr = page_address(page); + return 1U & (kaddr[offset] >> (nr & (BITS_PER_BYTE - 1))); +} + +/** + * extent_buffer_bitmap_set - set an area of a bitmap + * @eb: the extent buffer + * @start: offset of the bitmap item in the extent buffer + * @pos: bit number of the first bit + * @len: number of bits to set + */ +void extent_buffer_bitmap_set(struct extent_buffer *eb, unsigned long start, + unsigned long pos, unsigned long len) +{ + char *kaddr; + struct page *page; + unsigned long i; + size_t offset; + const unsigned int size = pos + len; + int bits_to_set = BITS_PER_BYTE - (pos % BITS_PER_BYTE); + unsigned int mask_to_set = BITMAP_FIRST_BYTE_MASK(pos); + + eb_bitmap_offset(eb, start, pos, &i, &offset); + page = eb->pages[i]; + WARN_ON(!PageUptodate(page)); + kaddr = page_address(page); + + while (len >= bits_to_set) { + kaddr[offset] |= mask_to_set; + len -= bits_to_set; + bits_to_set = BITS_PER_BYTE; + mask_to_set = ~0U; + if (++offset >= PAGE_CACHE_SIZE && len > 0) { + offset = 0; + page = eb->pages[++i]; + WARN_ON(!PageUptodate(page)); + kaddr = page_address(page); + } + } + if (len) { + mask_to_set &= BITMAP_LAST_BYTE_MASK(size); + kaddr[offset] |= mask_to_set; + } +} + + +/** + * extent_buffer_bitmap_clear - clear an area of a bitmap + * @eb: the extent buffer + * @start: offset of the bitmap item in the extent buffer + * @pos: bit number of the first bit + * @len: number of bits to clear + */ +void extent_buffer_bitmap_clear(struct extent_buffer *eb, unsigned long start, + unsigned long pos, unsigned long len) +{ + char *kaddr; + struct page *page; + unsigned long i; + size_t offset; + const unsigned int size = pos + len; + int bits_to_clear = BITS_PER_BYTE - (pos % BITS_PER_BYTE); + unsigned int mask_to_clear = BITMAP_FIRST_BYTE_MASK(pos); + + eb_bitmap_offset(eb, start, pos, &i, &offset); + page = eb->pages[i]; + WARN_ON(!PageUptodate(page)); + kaddr = page_address(page); + + while (len >= bits_to_clear) { + kaddr[offset] &= ~mask_to_clear; + len -= bits_to_clear; + bits_to_clear = BITS_PER_BYTE; + mask_to_clear = ~0U; + if (++offset >= PAGE_CACHE_SIZE && len > 0) { + offset = 0; + page = eb->pages[++i]; + WARN_ON(!PageUptodate(page)); + kaddr = page_address(page); + } + } + if (len) { + mask_to_clear &= BITMAP_LAST_BYTE_MASK(size); + kaddr[offset] &= ~mask_to_clear; + } +} + static inline bool areas_overlap(unsigned long src, unsigned long dst, unsigned long len) { unsigned long distance = (src > dst) ? src - dst : dst - src; diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h index 254f49157eaf..0377413bd4b9 100644 --- a/fs/btrfs/extent_io.h +++ b/fs/btrfs/extent_io.h @@ -350,8 +350,10 @@ void set_page_extent_mapped(struct page *page); struct extent_buffer *alloc_extent_buffer(struct btrfs_fs_info *fs_info, u64 start); +struct extent_buffer *__alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info, + u64 start, unsigned long len); struct extent_buffer *alloc_dummy_extent_buffer(struct btrfs_fs_info *fs_info, - u64 start); + u64 start); struct extent_buffer *btrfs_clone_extent_buffer(struct extent_buffer *src); struct extent_buffer *find_extent_buffer(struct btrfs_fs_info *fs_info, u64 start); @@ -396,6 +398,12 @@ void memmove_extent_buffer(struct extent_buffer *dst, unsigned long dst_offset, unsigned long src_offset, unsigned long len); void memset_extent_buffer(struct extent_buffer *eb, char c, unsigned long start, unsigned long len); +int extent_buffer_test_bit(struct extent_buffer *eb, unsigned long start, + unsigned long pos); +void extent_buffer_bitmap_set(struct extent_buffer *eb, unsigned long start, + unsigned long pos, unsigned long len); +void extent_buffer_bitmap_clear(struct extent_buffer *eb, unsigned long start, + unsigned long pos, unsigned long len); void clear_extent_buffer_dirty(struct extent_buffer *eb); int set_extent_buffer_dirty(struct extent_buffer *eb); void set_extent_buffer_uptodate(struct extent_buffer *eb); diff --git a/fs/btrfs/free-space-tree.c b/fs/btrfs/free-space-tree.c new file mode 100644 index 000000000000..cbe36dd0d97b --- /dev/null +++ b/fs/btrfs/free-space-tree.c @@ -0,0 +1,1584 @@ +/* + * Copyright (C) 2015 Facebook. All rights reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public + * License v2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public + * License along with this program; if not, write to the + * Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 021110-1307, USA. + */ + +#include +#include +#include "ctree.h" +#include "disk-io.h" +#include "locking.h" +#include "free-space-tree.h" +#include "transaction.h" + +static int __add_block_group_free_space(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + struct btrfs_block_group_cache *block_group, + struct btrfs_path *path); + +void set_free_space_tree_thresholds(struct btrfs_block_group_cache *cache) +{ + u32 bitmap_range; + size_t bitmap_size; + u64 num_bitmaps, total_bitmap_size; + + /* + * We convert to bitmaps when the disk space required for using extents + * exceeds that required for using bitmaps. + */ + bitmap_range = cache->sectorsize * BTRFS_FREE_SPACE_BITMAP_BITS; + num_bitmaps = div_u64(cache->key.offset + bitmap_range - 1, + bitmap_range); + bitmap_size = sizeof(struct btrfs_item) + BTRFS_FREE_SPACE_BITMAP_SIZE; + total_bitmap_size = num_bitmaps * bitmap_size; + cache->bitmap_high_thresh = div_u64(total_bitmap_size, + sizeof(struct btrfs_item)); + + /* + * We allow for a small buffer between the high threshold and low + * threshold to avoid thrashing back and forth between the two formats. + */ + if (cache->bitmap_high_thresh > 100) + cache->bitmap_low_thresh = cache->bitmap_high_thresh - 100; + else + cache->bitmap_low_thresh = 0; +} + +static int add_new_free_space_info(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + struct btrfs_block_group_cache *block_group, + struct btrfs_path *path) +{ + struct btrfs_root *root = fs_info->free_space_root; + struct btrfs_free_space_info *info; + struct btrfs_key key; + struct extent_buffer *leaf; + int ret; + + key.objectid = block_group->key.objectid; + key.type = BTRFS_FREE_SPACE_INFO_KEY; + key.offset = block_group->key.offset; + + ret = btrfs_insert_empty_item(trans, root, path, &key, sizeof(*info)); + if (ret) + goto out; + + leaf = path->nodes[0]; + info = btrfs_item_ptr(leaf, path->slots[0], + struct btrfs_free_space_info); + btrfs_set_free_space_extent_count(leaf, info, 0); + btrfs_set_free_space_flags(leaf, info, 0); + btrfs_mark_buffer_dirty(leaf); + + ret = 0; +out: + btrfs_release_path(path); + return ret; +} + +struct btrfs_free_space_info * +search_free_space_info(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + struct btrfs_block_group_cache *block_group, + struct btrfs_path *path, int cow) +{ + struct btrfs_root *root = fs_info->free_space_root; + struct btrfs_key key; + int ret; + + key.objectid = block_group->key.objectid; + key.type = BTRFS_FREE_SPACE_INFO_KEY; + key.offset = block_group->key.offset; + + ret = btrfs_search_slot(trans, root, &key, path, 0, cow); + if (ret < 0) + return ERR_PTR(ret); + if (ret != 0) { + btrfs_warn(fs_info, "missing free space info for %llu\n", + block_group->key.objectid); + ASSERT(0); + return ERR_PTR(-ENOENT); + } + + return btrfs_item_ptr(path->nodes[0], path->slots[0], + struct btrfs_free_space_info); +} + +/* + * btrfs_search_slot() but we're looking for the greatest key less than the + * passed key. + */ +static int btrfs_search_prev_slot(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_key *key, struct btrfs_path *p, + int ins_len, int cow) +{ + int ret; + + ret = btrfs_search_slot(trans, root, key, p, ins_len, cow); + if (ret < 0) + return ret; + + if (ret == 0) { + ASSERT(0); + return -EIO; + } + + if (p->slots[0] == 0) { + ASSERT(0); + return -EIO; + } + p->slots[0]--; + + return 0; +} + +static inline u32 free_space_bitmap_size(u64 size, u32 sectorsize) +{ + return DIV_ROUND_UP((u32)div_u64(size, sectorsize), BITS_PER_BYTE); +} + +static unsigned long *alloc_bitmap(u32 bitmap_size) +{ + return __vmalloc(bitmap_size, GFP_NOFS | __GFP_HIGHMEM | __GFP_ZERO, + PAGE_KERNEL); +} + +int convert_free_space_to_bitmaps(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + struct btrfs_block_group_cache *block_group, + struct btrfs_path *path) +{ + struct btrfs_root *root = fs_info->free_space_root; + struct btrfs_free_space_info *info; + struct btrfs_key key, found_key; + struct extent_buffer *leaf; + unsigned long *bitmap; + char *bitmap_cursor; + u64 start, end; + u64 bitmap_range, i; + u32 bitmap_size, flags, expected_extent_count; + u32 extent_count = 0; + int done = 0, nr; + int ret; + + bitmap_size = free_space_bitmap_size(block_group->key.offset, + block_group->sectorsize); + bitmap = alloc_bitmap(bitmap_size); + if (!bitmap) { + ret = -ENOMEM; + goto out; + } + + start = block_group->key.objectid; + end = block_group->key.objectid + block_group->key.offset; + + key.objectid = end - 1; + key.type = (u8)-1; + key.offset = (u64)-1; + + while (!done) { + ret = btrfs_search_prev_slot(trans, root, &key, path, -1, 1); + if (ret) + goto out; + + leaf = path->nodes[0]; + nr = 0; + path->slots[0]++; + while (path->slots[0] > 0) { + btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0] - 1); + + if (found_key.type == BTRFS_FREE_SPACE_INFO_KEY) { + ASSERT(found_key.objectid == block_group->key.objectid); + ASSERT(found_key.offset == block_group->key.offset); + done = 1; + break; + } else if (found_key.type == BTRFS_FREE_SPACE_EXTENT_KEY) { + u64 first, last; + + ASSERT(found_key.objectid >= start); + ASSERT(found_key.objectid < end); + ASSERT(found_key.objectid + found_key.offset <= end); + + first = div_u64(found_key.objectid - start, + block_group->sectorsize); + last = div_u64(found_key.objectid + found_key.offset - start, + block_group->sectorsize); + bitmap_set(bitmap, first, last - first); + + extent_count++; + nr++; + path->slots[0]--; + } else { + ASSERT(0); + } + } + + ret = btrfs_del_items(trans, root, path, path->slots[0], nr); + if (ret) + goto out; + btrfs_release_path(path); + } + + info = search_free_space_info(trans, fs_info, block_group, path, 1); + if (IS_ERR(info)) { + ret = PTR_ERR(info); + goto out; + } + leaf = path->nodes[0]; + flags = btrfs_free_space_flags(leaf, info); + flags |= BTRFS_FREE_SPACE_USING_BITMAPS; + btrfs_set_free_space_flags(leaf, info, flags); + expected_extent_count = btrfs_free_space_extent_count(leaf, info); + btrfs_mark_buffer_dirty(leaf); + btrfs_release_path(path); + + if (extent_count != expected_extent_count) { + btrfs_err(fs_info, "incorrect extent count for %llu; counted %u, expected %u", + block_group->key.objectid, extent_count, + expected_extent_count); + ASSERT(0); + ret = -EIO; + goto out; + } + + bitmap_cursor = (char *)bitmap; + bitmap_range = block_group->sectorsize * BTRFS_FREE_SPACE_BITMAP_BITS; + i = start; + while (i < end) { + unsigned long ptr; + u64 extent_size; + u32 data_size; + + extent_size = min(end - i, bitmap_range); + data_size = free_space_bitmap_size(extent_size, + block_group->sectorsize); + + key.objectid = i; + key.type = BTRFS_FREE_SPACE_BITMAP_KEY; + key.offset = extent_size; + + ret = btrfs_insert_empty_item(trans, root, path, &key, + data_size); + if (ret) + goto out; + + leaf = path->nodes[0]; + ptr = btrfs_item_ptr_offset(leaf, path->slots[0]); + write_extent_buffer(leaf, bitmap_cursor, ptr, + data_size); + btrfs_mark_buffer_dirty(leaf); + btrfs_release_path(path); + + i += extent_size; + bitmap_cursor += data_size; + } + + ret = 0; +out: + vfree(bitmap); + if (ret) + btrfs_abort_transaction(trans, root, ret); + return ret; +} + +int convert_free_space_to_extents(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + struct btrfs_block_group_cache *block_group, + struct btrfs_path *path) +{ + struct btrfs_root *root = fs_info->free_space_root; + struct btrfs_free_space_info *info; + struct btrfs_key key, found_key; + struct extent_buffer *leaf; + unsigned long *bitmap; + u64 start, end; + /* Initialize to silence GCC. */ + u64 extent_start = 0; + u64 offset; + u32 bitmap_size, flags, expected_extent_count; + int prev_bit = 0, bit, bitnr; + u32 extent_count = 0; + int done = 0, nr; + int ret; + + bitmap_size = free_space_bitmap_size(block_group->key.offset, + block_group->sectorsize); + bitmap = alloc_bitmap(bitmap_size); + if (!bitmap) { + ret = -ENOMEM; + goto out; + } + + start = block_group->key.objectid; + end = block_group->key.objectid + block_group->key.offset; + + key.objectid = end - 1; + key.type = (u8)-1; + key.offset = (u64)-1; + + while (!done) { + ret = btrfs_search_prev_slot(trans, root, &key, path, -1, 1); + if (ret) + goto out; + + leaf = path->nodes[0]; + nr = 0; + path->slots[0]++; + while (path->slots[0] > 0) { + btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0] - 1); + + if (found_key.type == BTRFS_FREE_SPACE_INFO_KEY) { + ASSERT(found_key.objectid == block_group->key.objectid); + ASSERT(found_key.offset == block_group->key.offset); + done = 1; + break; + } else if (found_key.type == BTRFS_FREE_SPACE_BITMAP_KEY) { + unsigned long ptr; + char *bitmap_cursor; + u32 bitmap_pos, data_size; + + ASSERT(found_key.objectid >= start); + ASSERT(found_key.objectid < end); + ASSERT(found_key.objectid + found_key.offset <= end); + + bitmap_pos = div_u64(found_key.objectid - start, + block_group->sectorsize * + BITS_PER_BYTE); + bitmap_cursor = ((char *)bitmap) + bitmap_pos; + data_size = free_space_bitmap_size(found_key.offset, + block_group->sectorsize); + + ptr = btrfs_item_ptr_offset(leaf, path->slots[0] - 1); + read_extent_buffer(leaf, bitmap_cursor, ptr, + data_size); + + nr++; + path->slots[0]--; + } else { + ASSERT(0); + } + } + + ret = btrfs_del_items(trans, root, path, path->slots[0], nr); + if (ret) + goto out; + btrfs_release_path(path); + } + + info = search_free_space_info(trans, fs_info, block_group, path, 1); + if (IS_ERR(info)) { + ret = PTR_ERR(info); + goto out; + } + leaf = path->nodes[0]; + flags = btrfs_free_space_flags(leaf, info); + flags &= ~BTRFS_FREE_SPACE_USING_BITMAPS; + btrfs_set_free_space_flags(leaf, info, flags); + expected_extent_count = btrfs_free_space_extent_count(leaf, info); + btrfs_mark_buffer_dirty(leaf); + btrfs_release_path(path); + + offset = start; + bitnr = 0; + while (offset < end) { + bit = !!test_bit(bitnr, bitmap); + if (prev_bit == 0 && bit == 1) { + extent_start = offset; + } else if (prev_bit == 1 && bit == 0) { + key.objectid = extent_start; + key.type = BTRFS_FREE_SPACE_EXTENT_KEY; + key.offset = offset - extent_start; + + ret = btrfs_insert_empty_item(trans, root, path, &key, 0); + if (ret) + goto out; + btrfs_release_path(path); + + extent_count++; + } + prev_bit = bit; + offset += block_group->sectorsize; + bitnr++; + } + if (prev_bit == 1) { + key.objectid = extent_start; + key.type = BTRFS_FREE_SPACE_EXTENT_KEY; + key.offset = end - extent_start; + + ret = btrfs_insert_empty_item(trans, root, path, &key, 0); + if (ret) + goto out; + btrfs_release_path(path); + + extent_count++; + } + + if (extent_count != expected_extent_count) { + btrfs_err(fs_info, "incorrect extent count for %llu; counted %u, expected %u", + block_group->key.objectid, extent_count, + expected_extent_count); + ASSERT(0); + ret = -EIO; + goto out; + } + + ret = 0; +out: + vfree(bitmap); + if (ret) + btrfs_abort_transaction(trans, root, ret); + return ret; +} + +static int update_free_space_extent_count(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + struct btrfs_block_group_cache *block_group, + struct btrfs_path *path, + int new_extents) +{ + struct btrfs_free_space_info *info; + u32 flags; + u32 extent_count; + int ret = 0; + + if (new_extents == 0) + return 0; + + info = search_free_space_info(trans, fs_info, block_group, path, 1); + if (IS_ERR(info)) { + ret = PTR_ERR(info); + goto out; + } + flags = btrfs_free_space_flags(path->nodes[0], info); + extent_count = btrfs_free_space_extent_count(path->nodes[0], info); + + extent_count += new_extents; + btrfs_set_free_space_extent_count(path->nodes[0], info, extent_count); + btrfs_mark_buffer_dirty(path->nodes[0]); + btrfs_release_path(path); + + if (!(flags & BTRFS_FREE_SPACE_USING_BITMAPS) && + extent_count > block_group->bitmap_high_thresh) { + ret = convert_free_space_to_bitmaps(trans, fs_info, block_group, + path); + } else if ((flags & BTRFS_FREE_SPACE_USING_BITMAPS) && + extent_count < block_group->bitmap_low_thresh) { + ret = convert_free_space_to_extents(trans, fs_info, block_group, + path); + } + +out: + return ret; +} + +int free_space_test_bit(struct btrfs_block_group_cache *block_group, + struct btrfs_path *path, u64 offset) +{ + struct extent_buffer *leaf; + struct btrfs_key key; + u64 found_start, found_end; + unsigned long ptr, i; + + leaf = path->nodes[0]; + btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); + ASSERT(key.type == BTRFS_FREE_SPACE_BITMAP_KEY); + + found_start = key.objectid; + found_end = key.objectid + key.offset; + ASSERT(offset >= found_start && offset < found_end); + + ptr = btrfs_item_ptr_offset(leaf, path->slots[0]); + i = div_u64(offset - found_start, block_group->sectorsize); + return !!extent_buffer_test_bit(leaf, ptr, i); +} + +static void free_space_set_bits(struct btrfs_block_group_cache *block_group, + struct btrfs_path *path, u64 *start, u64 *size, + int bit) +{ + struct extent_buffer *leaf; + struct btrfs_key key; + u64 end = *start + *size; + u64 found_start, found_end; + unsigned long ptr, first, last; + + leaf = path->nodes[0]; + btrfs_item_key_to_cpu(leaf, &key, path->slots[0]); + ASSERT(key.type == BTRFS_FREE_SPACE_BITMAP_KEY); + + found_start = key.objectid; + found_end = key.objectid + key.offset; + ASSERT(*start >= found_start && *start < found_end); + ASSERT(end > found_start); + + if (end > found_end) + end = found_end; + + ptr = btrfs_item_ptr_offset(leaf, path->slots[0]); + first = div_u64(*start - found_start, block_group->sectorsize); + last = div_u64(end - found_start, block_group->sectorsize); + if (bit) + extent_buffer_bitmap_set(leaf, ptr, first, last - first); + else + extent_buffer_bitmap_clear(leaf, ptr, first, last - first); + btrfs_mark_buffer_dirty(leaf); + + *size -= end - *start; + *start = end; +} + +/* + * We can't use btrfs_next_item() in modify_free_space_bitmap() because + * btrfs_next_leaf() doesn't get the path for writing. We can forgo the fancy + * tree walking in btrfs_next_leaf() anyways because we know exactly what we're + * looking for. + */ +static int free_space_next_bitmap(struct btrfs_trans_handle *trans, + struct btrfs_root *root, struct btrfs_path *p) +{ + struct btrfs_key key; + + if (p->slots[0] + 1 < btrfs_header_nritems(p->nodes[0])) { + p->slots[0]++; + return 0; + } + + btrfs_item_key_to_cpu(p->nodes[0], &key, p->slots[0]); + btrfs_release_path(p); + + key.objectid += key.offset; + key.type = (u8)-1; + key.offset = (u64)-1; + + return btrfs_search_prev_slot(trans, root, &key, p, 0, 1); +} + +/* + * If remove is 1, then we are removing free space, thus clearing bits in the + * bitmap. If remove is 0, then we are adding free space, thus setting bits in + * the bitmap. + */ +static int modify_free_space_bitmap(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + struct btrfs_block_group_cache *block_group, + struct btrfs_path *path, + u64 start, u64 size, int remove) +{ + struct btrfs_root *root = fs_info->free_space_root; + struct btrfs_key key; + u64 end = start + size; + u64 cur_start, cur_size; + int prev_bit, next_bit; + int new_extents; + int ret; + + /* + * Read the bit for the block immediately before the extent of space if + * that block is within the block group. + */ + if (start > block_group->key.objectid) { + u64 prev_block = start - block_group->sectorsize; + + key.objectid = prev_block; + key.type = (u8)-1; + key.offset = (u64)-1; + + ret = btrfs_search_prev_slot(trans, root, &key, path, 0, 1); + if (ret) + goto out; + + prev_bit = free_space_test_bit(block_group, path, prev_block); + + /* The previous block may have been in the previous bitmap. */ + btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); + if (start >= key.objectid + key.offset) { + ret = free_space_next_bitmap(trans, root, path); + if (ret) + goto out; + } + } else { + key.objectid = start; + key.type = (u8)-1; + key.offset = (u64)-1; + + ret = btrfs_search_prev_slot(trans, root, &key, path, 0, 1); + if (ret) + goto out; + + prev_bit = -1; + } + + /* + * Iterate over all of the bitmaps overlapped by the extent of space, + * clearing/setting bits as required. + */ + cur_start = start; + cur_size = size; + while (1) { + free_space_set_bits(block_group, path, &cur_start, &cur_size, + !remove); + if (cur_size == 0) + break; + ret = free_space_next_bitmap(trans, root, path); + if (ret) + goto out; + } + + /* + * Read the bit for the block immediately after the extent of space if + * that block is within the block group. + */ + if (end < block_group->key.objectid + block_group->key.offset) { + /* The next block may be in the next bitmap. */ + btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); + if (end >= key.objectid + key.offset) { + ret = free_space_next_bitmap(trans, root, path); + if (ret) + goto out; + } + + next_bit = free_space_test_bit(block_group, path, end); + } else { + next_bit = -1; + } + + if (remove) { + new_extents = -1; + if (prev_bit == 1) { + /* Leftover on the left. */ + new_extents++; + } + if (next_bit == 1) { + /* Leftover on the right. */ + new_extents++; + } + } else { + new_extents = 1; + if (prev_bit == 1) { + /* Merging with neighbor on the left. */ + new_extents--; + } + if (next_bit == 1) { + /* Merging with neighbor on the right. */ + new_extents--; + } + } + + btrfs_release_path(path); + ret = update_free_space_extent_count(trans, fs_info, block_group, path, + new_extents); + +out: + return ret; +} + +static int remove_free_space_extent(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + struct btrfs_block_group_cache *block_group, + struct btrfs_path *path, + u64 start, u64 size) +{ + struct btrfs_root *root = fs_info->free_space_root; + struct btrfs_key key; + u64 found_start, found_end; + u64 end = start + size; + int new_extents = -1; + int ret; + + key.objectid = start; + key.type = (u8)-1; + key.offset = (u64)-1; + + ret = btrfs_search_prev_slot(trans, root, &key, path, -1, 1); + if (ret) + goto out; + + btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); + + ASSERT(key.type == BTRFS_FREE_SPACE_EXTENT_KEY); + + found_start = key.objectid; + found_end = key.objectid + key.offset; + ASSERT(start >= found_start && end <= found_end); + + /* + * Okay, now that we've found the free space extent which contains the + * free space that we are removing, there are four cases: + * + * 1. We're using the whole extent: delete the key we found and + * decrement the free space extent count. + * 2. We are using part of the extent starting at the beginning: delete + * the key we found and insert a new key representing the leftover at + * the end. There is no net change in the number of extents. + * 3. We are using part of the extent ending at the end: delete the key + * we found and insert a new key representing the leftover at the + * beginning. There is no net change in the number of extents. + * 4. We are using part of the extent in the middle: delete the key we + * found and insert two new keys representing the leftovers on each + * side. Where we used to have one extent, we now have two, so increment + * the extent count. We may need to convert the block group to bitmaps + * as a result. + */ + + /* Delete the existing key (cases 1-4). */ + ret = btrfs_del_item(trans, root, path); + if (ret) + goto out; + + /* Add a key for leftovers at the beginning (cases 3 and 4). */ + if (start > found_start) { + key.objectid = found_start; + key.type = BTRFS_FREE_SPACE_EXTENT_KEY; + key.offset = start - found_start; + + btrfs_release_path(path); + ret = btrfs_insert_empty_item(trans, root, path, &key, 0); + if (ret) + goto out; + new_extents++; + } + + /* Add a key for leftovers at the end (cases 2 and 4). */ + if (end < found_end) { + key.objectid = end; + key.type = BTRFS_FREE_SPACE_EXTENT_KEY; + key.offset = found_end - end; + + btrfs_release_path(path); + ret = btrfs_insert_empty_item(trans, root, path, &key, 0); + if (ret) + goto out; + new_extents++; + } + + btrfs_release_path(path); + ret = update_free_space_extent_count(trans, fs_info, block_group, path, + new_extents); + +out: + return ret; +} + +int __remove_from_free_space_tree(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + struct btrfs_block_group_cache *block_group, + struct btrfs_path *path, u64 start, u64 size) +{ + struct btrfs_free_space_info *info; + u32 flags; + int ret; + + if (block_group->needs_free_space) { + ret = __add_block_group_free_space(trans, fs_info, block_group, + path); + if (ret) + return ret; + } + + info = search_free_space_info(NULL, fs_info, block_group, path, 0); + if (IS_ERR(info)) + return PTR_ERR(info); + flags = btrfs_free_space_flags(path->nodes[0], info); + btrfs_release_path(path); + + if (flags & BTRFS_FREE_SPACE_USING_BITMAPS) { + return modify_free_space_bitmap(trans, fs_info, block_group, + path, start, size, 1); + } else { + return remove_free_space_extent(trans, fs_info, block_group, + path, start, size); + } +} + +int remove_from_free_space_tree(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + u64 start, u64 size) +{ + struct btrfs_block_group_cache *block_group; + struct btrfs_path *path; + int ret; + + if (!btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) + return 0; + + path = btrfs_alloc_path(); + if (!path) { + ret = -ENOMEM; + goto out; + } + + block_group = btrfs_lookup_block_group(fs_info, start); + if (!block_group) { + ASSERT(0); + ret = -ENOENT; + goto out; + } + + mutex_lock(&block_group->free_space_lock); + ret = __remove_from_free_space_tree(trans, fs_info, block_group, path, + start, size); + mutex_unlock(&block_group->free_space_lock); + + btrfs_put_block_group(block_group); +out: + btrfs_free_path(path); + if (ret) + btrfs_abort_transaction(trans, fs_info->free_space_root, ret); + return ret; +} + +static int add_free_space_extent(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + struct btrfs_block_group_cache *block_group, + struct btrfs_path *path, + u64 start, u64 size) +{ + struct btrfs_root *root = fs_info->free_space_root; + struct btrfs_key key, new_key; + u64 found_start, found_end; + u64 end = start + size; + int new_extents = 1; + int ret; + + /* + * We are adding a new extent of free space, but we need to merge + * extents. There are four cases here: + * + * 1. The new extent does not have any immediate neighbors to merge + * with: add the new key and increment the free space extent count. We + * may need to convert the block group to bitmaps as a result. + * 2. The new extent has an immediate neighbor before it: remove the + * previous key and insert a new key combining both of them. There is no + * net change in the number of extents. + * 3. The new extent has an immediate neighbor after it: remove the next + * key and insert a new key combining both of them. There is no net + * change in the number of extents. + * 4. The new extent has immediate neighbors on both sides: remove both + * of the keys and insert a new key combining all of them. Where we used + * to have two extents, we now have one, so decrement the extent count. + */ + + new_key.objectid = start; + new_key.type = BTRFS_FREE_SPACE_EXTENT_KEY; + new_key.offset = size; + + /* Search for a neighbor on the left. */ + if (start == block_group->key.objectid) + goto right; + key.objectid = start - 1; + key.type = (u8)-1; + key.offset = (u64)-1; + + ret = btrfs_search_prev_slot(trans, root, &key, path, -1, 1); + if (ret) + goto out; + + btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); + + if (key.type != BTRFS_FREE_SPACE_EXTENT_KEY) { + ASSERT(key.type == BTRFS_FREE_SPACE_INFO_KEY); + btrfs_release_path(path); + goto right; + } + + found_start = key.objectid; + found_end = key.objectid + key.offset; + ASSERT(found_start >= block_group->key.objectid && + found_end > block_group->key.objectid); + ASSERT(found_start < start && found_end <= start); + + /* + * Delete the neighbor on the left and absorb it into the new key (cases + * 2 and 4). + */ + if (found_end == start) { + ret = btrfs_del_item(trans, root, path); + if (ret) + goto out; + new_key.objectid = found_start; + new_key.offset += key.offset; + new_extents--; + } + btrfs_release_path(path); + +right: + /* Search for a neighbor on the right. */ + if (end == block_group->key.objectid + block_group->key.offset) + goto insert; + key.objectid = end; + key.type = (u8)-1; + key.offset = (u64)-1; + + ret = btrfs_search_prev_slot(trans, root, &key, path, -1, 1); + if (ret) + goto out; + + btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); + + if (key.type != BTRFS_FREE_SPACE_EXTENT_KEY) { + ASSERT(key.type == BTRFS_FREE_SPACE_INFO_KEY); + btrfs_release_path(path); + goto insert; + } + + found_start = key.objectid; + found_end = key.objectid + key.offset; + ASSERT(found_start >= block_group->key.objectid && + found_end > block_group->key.objectid); + ASSERT((found_start < start && found_end <= start) || + (found_start >= end && found_end > end)); + + /* + * Delete the neighbor on the right and absorb it into the new key + * (cases 3 and 4). + */ + if (found_start == end) { + ret = btrfs_del_item(trans, root, path); + if (ret) + goto out; + new_key.offset += key.offset; + new_extents--; + } + btrfs_release_path(path); + +insert: + /* Insert the new key (cases 1-4). */ + ret = btrfs_insert_empty_item(trans, root, path, &new_key, 0); + if (ret) + goto out; + + btrfs_release_path(path); + ret = update_free_space_extent_count(trans, fs_info, block_group, path, + new_extents); + +out: + return ret; +} + +int __add_to_free_space_tree(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + struct btrfs_block_group_cache *block_group, + struct btrfs_path *path, u64 start, u64 size) +{ + struct btrfs_free_space_info *info; + u32 flags; + int ret; + + if (block_group->needs_free_space) { + ret = __add_block_group_free_space(trans, fs_info, block_group, + path); + if (ret) + return ret; + } + + info = search_free_space_info(NULL, fs_info, block_group, path, 0); + if (IS_ERR(info)) + return PTR_ERR(info); + flags = btrfs_free_space_flags(path->nodes[0], info); + btrfs_release_path(path); + + if (flags & BTRFS_FREE_SPACE_USING_BITMAPS) { + return modify_free_space_bitmap(trans, fs_info, block_group, + path, start, size, 0); + } else { + return add_free_space_extent(trans, fs_info, block_group, path, + start, size); + } +} + +int add_to_free_space_tree(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + u64 start, u64 size) +{ + struct btrfs_block_group_cache *block_group; + struct btrfs_path *path; + int ret; + + if (!btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) + return 0; + + path = btrfs_alloc_path(); + if (!path) { + ret = -ENOMEM; + goto out; + } + + block_group = btrfs_lookup_block_group(fs_info, start); + if (!block_group) { + ASSERT(0); + ret = -ENOENT; + goto out; + } + + mutex_lock(&block_group->free_space_lock); + ret = __add_to_free_space_tree(trans, fs_info, block_group, path, start, + size); + mutex_unlock(&block_group->free_space_lock); + + btrfs_put_block_group(block_group); +out: + btrfs_free_path(path); + if (ret) + btrfs_abort_transaction(trans, fs_info->free_space_root, ret); + return ret; +} + +/* + * Populate the free space tree by walking the extent tree. Operations on the + * extent tree that happen as a result of writes to the free space tree will go + * through the normal add/remove hooks. + */ +static int populate_free_space_tree(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + struct btrfs_block_group_cache *block_group) +{ + struct btrfs_root *extent_root = fs_info->extent_root; + struct btrfs_path *path, *path2; + struct btrfs_key key; + u64 start, end; + int ret; + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + path->reada = 1; + + path2 = btrfs_alloc_path(); + if (!path2) { + btrfs_free_path(path); + return -ENOMEM; + } + + ret = add_new_free_space_info(trans, fs_info, block_group, path2); + if (ret) + goto out; + + /* + * Iterate through all of the extent and metadata items in this block + * group, adding the free space between them and the free space at the + * end. Note that EXTENT_ITEM and METADATA_ITEM are less than + * BLOCK_GROUP_ITEM, so an extent may precede the block group that it's + * contained in. + */ + key.objectid = block_group->key.objectid; + key.type = BTRFS_EXTENT_ITEM_KEY; + key.offset = 0; + + ret = btrfs_search_slot_for_read(extent_root, &key, path, 1, 0); + if (ret < 0) + goto out; + ASSERT(ret == 0); + + start = block_group->key.objectid; + end = block_group->key.objectid + block_group->key.offset; + while (1) { + btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); + + if (key.type == BTRFS_EXTENT_ITEM_KEY || + key.type == BTRFS_METADATA_ITEM_KEY) { + if (key.objectid >= end) + break; + + if (start < key.objectid) { + ret = __add_to_free_space_tree(trans, fs_info, + block_group, + path2, start, + key.objectid - + start); + if (ret) + goto out; + } + start = key.objectid; + if (key.type == BTRFS_METADATA_ITEM_KEY) + start += fs_info->tree_root->nodesize; + else + start += key.offset; + } else if (key.type == BTRFS_BLOCK_GROUP_ITEM_KEY) { + if (key.objectid != block_group->key.objectid) + break; + } + + ret = btrfs_next_item(extent_root, path); + if (ret < 0) + goto out; + if (ret) + break; + } + if (start < end) { + ret = __add_to_free_space_tree(trans, fs_info, block_group, + path2, start, end - start); + if (ret) + goto out; + } + + ret = 0; +out: + btrfs_free_path(path2); + btrfs_free_path(path); + return ret; +} + +int btrfs_create_free_space_tree(struct btrfs_fs_info *fs_info) +{ + struct btrfs_trans_handle *trans; + struct btrfs_root *tree_root = fs_info->tree_root; + struct btrfs_root *free_space_root; + struct btrfs_block_group_cache *block_group; + struct rb_node *node; + int ret; + + trans = btrfs_start_transaction(tree_root, 0); + if (IS_ERR(trans)) + return PTR_ERR(trans); + + free_space_root = btrfs_create_tree(trans, fs_info, + BTRFS_FREE_SPACE_TREE_OBJECTID); + if (IS_ERR(free_space_root)) { + ret = PTR_ERR(free_space_root); + goto abort; + } + fs_info->free_space_root = free_space_root; + + node = rb_first(&fs_info->block_group_cache_tree); + while (node) { + block_group = rb_entry(node, struct btrfs_block_group_cache, + cache_node); + ret = populate_free_space_tree(trans, fs_info, block_group); + if (ret) + goto abort; + node = rb_next(node); + } + + btrfs_set_fs_compat_ro(fs_info, FREE_SPACE_TREE); + + ret = btrfs_commit_transaction(trans, tree_root); + if (ret) + return ret; + + return 0; + +abort: + btrfs_abort_transaction(trans, tree_root, ret); + btrfs_end_transaction(trans, tree_root); + return ret; +} + +static int clear_free_space_tree(struct btrfs_trans_handle *trans, + struct btrfs_root *root) +{ + struct btrfs_path *path; + struct btrfs_key key; + int nr; + int ret; + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + path->leave_spinning = 1; + + key.objectid = 0; + key.type = 0; + key.offset = 0; + + while (1) { + ret = btrfs_search_slot(trans, root, &key, path, -1, 1); + if (ret < 0) + goto out; + + nr = btrfs_header_nritems(path->nodes[0]); + if (!nr) + break; + + path->slots[0] = 0; + ret = btrfs_del_items(trans, root, path, 0, nr); + if (ret) + goto out; + + btrfs_release_path(path); + } + + ret = 0; +out: + btrfs_free_path(path); + return ret; +} + +int btrfs_clear_free_space_tree(struct btrfs_fs_info *fs_info) +{ + struct btrfs_trans_handle *trans; + struct btrfs_root *tree_root = fs_info->tree_root; + struct btrfs_root *free_space_root = fs_info->free_space_root; + int ret; + + trans = btrfs_start_transaction(tree_root, 0); + if (IS_ERR(trans)) + return PTR_ERR(trans); + + btrfs_clear_fs_compat_ro(fs_info, FREE_SPACE_TREE); + fs_info->free_space_root = NULL; + + ret = clear_free_space_tree(trans, free_space_root); + if (ret) + goto abort; + + ret = btrfs_del_root(trans, tree_root, &free_space_root->root_key); + if (ret) + goto abort; + + list_del(&free_space_root->dirty_list); + + btrfs_tree_lock(free_space_root->node); + clean_tree_block(trans, tree_root->fs_info, free_space_root->node); + btrfs_tree_unlock(free_space_root->node); + btrfs_free_tree_block(trans, free_space_root, free_space_root->node, + 0, 1); + + free_extent_buffer(free_space_root->node); + free_extent_buffer(free_space_root->commit_root); + kfree(free_space_root); + + ret = btrfs_commit_transaction(trans, tree_root); + if (ret) + return ret; + + return 0; + +abort: + btrfs_abort_transaction(trans, tree_root, ret); + btrfs_end_transaction(trans, tree_root); + return ret; +} + +static int __add_block_group_free_space(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + struct btrfs_block_group_cache *block_group, + struct btrfs_path *path) +{ + u64 start, end; + int ret; + + start = block_group->key.objectid; + end = block_group->key.objectid + block_group->key.offset; + + block_group->needs_free_space = 0; + + ret = add_new_free_space_info(trans, fs_info, block_group, path); + if (ret) + return ret; + + return __add_to_free_space_tree(trans, fs_info, block_group, path, + block_group->key.objectid, + block_group->key.offset); +} + +int add_block_group_free_space(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + struct btrfs_block_group_cache *block_group) +{ + struct btrfs_path *path = NULL; + int ret = 0; + + if (!btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) + return 0; + + mutex_lock(&block_group->free_space_lock); + if (!block_group->needs_free_space) + goto out; + + path = btrfs_alloc_path(); + if (!path) { + ret = -ENOMEM; + goto out; + } + + ret = __add_block_group_free_space(trans, fs_info, block_group, path); + +out: + btrfs_free_path(path); + mutex_unlock(&block_group->free_space_lock); + if (ret) + btrfs_abort_transaction(trans, fs_info->free_space_root, ret); + return ret; +} + +int remove_block_group_free_space(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + struct btrfs_block_group_cache *block_group) +{ + struct btrfs_root *root = fs_info->free_space_root; + struct btrfs_path *path; + struct btrfs_key key, found_key; + struct extent_buffer *leaf; + u64 start, end; + int done = 0, nr; + int ret; + + if (!btrfs_fs_compat_ro(fs_info, FREE_SPACE_TREE)) + return 0; + + if (block_group->needs_free_space) { + /* We never added this block group to the free space tree. */ + return 0; + } + + path = btrfs_alloc_path(); + if (!path) { + ret = -ENOMEM; + goto out; + } + + start = block_group->key.objectid; + end = block_group->key.objectid + block_group->key.offset; + + key.objectid = end - 1; + key.type = (u8)-1; + key.offset = (u64)-1; + + while (!done) { + ret = btrfs_search_prev_slot(trans, root, &key, path, -1, 1); + if (ret) + goto out; + + leaf = path->nodes[0]; + nr = 0; + path->slots[0]++; + while (path->slots[0] > 0) { + btrfs_item_key_to_cpu(leaf, &found_key, path->slots[0] - 1); + + if (found_key.type == BTRFS_FREE_SPACE_INFO_KEY) { + ASSERT(found_key.objectid == block_group->key.objectid); + ASSERT(found_key.offset == block_group->key.offset); + done = 1; + nr++; + path->slots[0]--; + break; + } else if (found_key.type == BTRFS_FREE_SPACE_EXTENT_KEY || + found_key.type == BTRFS_FREE_SPACE_BITMAP_KEY) { + ASSERT(found_key.objectid >= start); + ASSERT(found_key.objectid < end); + ASSERT(found_key.objectid + found_key.offset <= end); + nr++; + path->slots[0]--; + } else { + ASSERT(0); + } + } + + ret = btrfs_del_items(trans, root, path, path->slots[0], nr); + if (ret) + goto out; + btrfs_release_path(path); + } + + ret = 0; +out: + btrfs_free_path(path); + if (ret) + btrfs_abort_transaction(trans, root, ret); + return ret; +} + +static int load_free_space_bitmaps(struct btrfs_caching_control *caching_ctl, + struct btrfs_path *path, + u32 expected_extent_count) +{ + struct btrfs_block_group_cache *block_group; + struct btrfs_fs_info *fs_info; + struct btrfs_root *root; + struct btrfs_key key; + int prev_bit = 0, bit; + /* Initialize to silence GCC. */ + u64 extent_start = 0; + u64 end, offset; + u64 total_found = 0; + u32 extent_count = 0; + int ret; + + block_group = caching_ctl->block_group; + fs_info = block_group->fs_info; + root = fs_info->free_space_root; + + end = block_group->key.objectid + block_group->key.offset; + + while (1) { + ret = btrfs_next_item(root, path); + if (ret < 0) + goto out; + if (ret) + break; + + btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); + + if (key.type == BTRFS_FREE_SPACE_INFO_KEY) + break; + + ASSERT(key.type == BTRFS_FREE_SPACE_BITMAP_KEY); + ASSERT(key.objectid < end && key.objectid + key.offset <= end); + + caching_ctl->progress = key.objectid; + + offset = key.objectid; + while (offset < key.objectid + key.offset) { + bit = free_space_test_bit(block_group, path, offset); + if (prev_bit == 0 && bit == 1) { + extent_start = offset; + } else if (prev_bit == 1 && bit == 0) { + total_found += add_new_free_space(block_group, + fs_info, + extent_start, + offset); + if (total_found > CACHING_CTL_WAKE_UP) { + total_found = 0; + wake_up(&caching_ctl->wait); + } + extent_count++; + } + prev_bit = bit; + offset += block_group->sectorsize; + } + } + if (prev_bit == 1) { + total_found += add_new_free_space(block_group, fs_info, + extent_start, end); + extent_count++; + } + + if (extent_count != expected_extent_count) { + btrfs_err(fs_info, "incorrect extent count for %llu; counted %u, expected %u", + block_group->key.objectid, extent_count, + expected_extent_count); + ASSERT(0); + ret = -EIO; + goto out; + } + + caching_ctl->progress = (u64)-1; + + ret = 0; +out: + return ret; +} + +static int load_free_space_extents(struct btrfs_caching_control *caching_ctl, + struct btrfs_path *path, + u32 expected_extent_count) +{ + struct btrfs_block_group_cache *block_group; + struct btrfs_fs_info *fs_info; + struct btrfs_root *root; + struct btrfs_key key; + u64 end; + u64 total_found = 0; + u32 extent_count = 0; + int ret; + + block_group = caching_ctl->block_group; + fs_info = block_group->fs_info; + root = fs_info->free_space_root; + + end = block_group->key.objectid + block_group->key.offset; + + while (1) { + ret = btrfs_next_item(root, path); + if (ret < 0) + goto out; + if (ret) + break; + + btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); + + if (key.type == BTRFS_FREE_SPACE_INFO_KEY) + break; + + ASSERT(key.type == BTRFS_FREE_SPACE_EXTENT_KEY); + ASSERT(key.objectid < end && key.objectid + key.offset <= end); + + caching_ctl->progress = key.objectid; + + total_found += add_new_free_space(block_group, fs_info, + key.objectid, + key.objectid + key.offset); + if (total_found > CACHING_CTL_WAKE_UP) { + total_found = 0; + wake_up(&caching_ctl->wait); + } + extent_count++; + } + + if (extent_count != expected_extent_count) { + btrfs_err(fs_info, "incorrect extent count for %llu; counted %u, expected %u", + block_group->key.objectid, extent_count, + expected_extent_count); + ASSERT(0); + ret = -EIO; + goto out; + } + + caching_ctl->progress = (u64)-1; + + ret = 0; +out: + return ret; +} + +int load_free_space_tree(struct btrfs_caching_control *caching_ctl) +{ + struct btrfs_block_group_cache *block_group; + struct btrfs_fs_info *fs_info; + struct btrfs_free_space_info *info; + struct btrfs_path *path; + u32 extent_count, flags; + int ret; + + block_group = caching_ctl->block_group; + fs_info = block_group->fs_info; + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + /* + * Just like caching_thread() doesn't want to deadlock on the extent + * tree, we don't want to deadlock on the free space tree. + */ + path->skip_locking = 1; + path->search_commit_root = 1; + path->reada = 1; + + info = search_free_space_info(NULL, fs_info, block_group, path, 0); + if (IS_ERR(info)) { + ret = PTR_ERR(info); + goto out; + } + extent_count = btrfs_free_space_extent_count(path->nodes[0], info); + flags = btrfs_free_space_flags(path->nodes[0], info); + + /* + * We left path pointing to the free space info item, so now + * load_free_space_foo can just iterate through the free space tree from + * there. + */ + if (flags & BTRFS_FREE_SPACE_USING_BITMAPS) + ret = load_free_space_bitmaps(caching_ctl, path, extent_count); + else + ret = load_free_space_extents(caching_ctl, path, extent_count); + +out: + btrfs_free_path(path); + return ret; +} diff --git a/fs/btrfs/free-space-tree.h b/fs/btrfs/free-space-tree.h new file mode 100644 index 000000000000..54ffced3bce8 --- /dev/null +++ b/fs/btrfs/free-space-tree.h @@ -0,0 +1,72 @@ +/* + * Copyright (C) 2015 Facebook. All rights reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public + * License v2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public + * License along with this program; if not, write to the + * Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 021110-1307, USA. + */ + +#ifndef __BTRFS_FREE_SPACE_TREE +#define __BTRFS_FREE_SPACE_TREE + +/* + * The default size for new free space bitmap items. The last bitmap in a block + * group may be truncated, and none of the free space tree code assumes that + * existing bitmaps are this size. + */ +#define BTRFS_FREE_SPACE_BITMAP_SIZE 256 +#define BTRFS_FREE_SPACE_BITMAP_BITS (BTRFS_FREE_SPACE_BITMAP_SIZE * BITS_PER_BYTE) + +void set_free_space_tree_thresholds(struct btrfs_block_group_cache *block_group); +int btrfs_create_free_space_tree(struct btrfs_fs_info *fs_info); +int btrfs_clear_free_space_tree(struct btrfs_fs_info *fs_info); +int load_free_space_tree(struct btrfs_caching_control *caching_ctl); +int add_block_group_free_space(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + struct btrfs_block_group_cache *block_group); +int remove_block_group_free_space(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + struct btrfs_block_group_cache *block_group); +int add_to_free_space_tree(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + u64 start, u64 size); +int remove_from_free_space_tree(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + u64 start, u64 size); + +/* Exposed for testing. */ +struct btrfs_free_space_info * +search_free_space_info(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + struct btrfs_block_group_cache *block_group, + struct btrfs_path *path, int cow); +int __add_to_free_space_tree(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + struct btrfs_block_group_cache *block_group, + struct btrfs_path *path, u64 start, u64 size); +int __remove_from_free_space_tree(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + struct btrfs_block_group_cache *block_group, + struct btrfs_path *path, u64 start, u64 size); +int convert_free_space_to_bitmaps(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + struct btrfs_block_group_cache *block_group, + struct btrfs_path *path); +int convert_free_space_to_extents(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + struct btrfs_block_group_cache *block_group, + struct btrfs_path *path); +int free_space_test_bit(struct btrfs_block_group_cache *block_group, + struct btrfs_path *path, u64 offset); + +#endif diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index 24154e422945..9153d54d27c8 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -295,10 +295,11 @@ enum { Opt_nossd, Opt_ssd_spread, Opt_thread_pool, Opt_noacl, Opt_compress, Opt_compress_type, Opt_compress_force, Opt_compress_force_type, Opt_notreelog, Opt_ratio, Opt_flushoncommit, Opt_discard, - Opt_space_cache, Opt_clear_cache, Opt_user_subvol_rm_allowed, - Opt_enospc_debug, Opt_subvolrootid, Opt_defrag, Opt_inode_cache, - Opt_no_space_cache, Opt_recovery, Opt_skip_balance, - Opt_check_integrity, Opt_check_integrity_including_extent_data, + Opt_space_cache, Opt_space_cache_version, Opt_clear_cache, + Opt_user_subvol_rm_allowed, Opt_enospc_debug, Opt_subvolrootid, + Opt_defrag, Opt_inode_cache, Opt_no_space_cache, Opt_recovery, + Opt_skip_balance, Opt_check_integrity, + Opt_check_integrity_including_extent_data, Opt_check_integrity_print_mask, Opt_fatal_errors, Opt_rescan_uuid_tree, Opt_commit_interval, Opt_barrier, Opt_nodefrag, Opt_nodiscard, Opt_noenospc_debug, Opt_noflushoncommit, Opt_acl, Opt_datacow, @@ -340,6 +341,7 @@ static match_table_t tokens = { {Opt_discard, "discard"}, {Opt_nodiscard, "nodiscard"}, {Opt_space_cache, "space_cache"}, + {Opt_space_cache_version, "space_cache=%s"}, {Opt_clear_cache, "clear_cache"}, {Opt_user_subvol_rm_allowed, "user_subvol_rm_allowed"}, {Opt_enospc_debug, "enospc_debug"}, @@ -383,7 +385,9 @@ int btrfs_parse_options(struct btrfs_root *root, char *options) bool compress_force = false; cache_gen = btrfs_super_cache_generation(root->fs_info->super_copy); - if (cache_gen) + if (btrfs_fs_compat_ro(root->fs_info, FREE_SPACE_TREE)) + btrfs_set_opt(info->mount_opt, FREE_SPACE_TREE); + else if (cache_gen) btrfs_set_opt(info->mount_opt, SPACE_CACHE); if (!options) @@ -617,15 +621,35 @@ int btrfs_parse_options(struct btrfs_root *root, char *options) "turning off discard"); break; case Opt_space_cache: - btrfs_set_and_info(root, SPACE_CACHE, - "enabling disk space caching"); + case Opt_space_cache_version: + if (token == Opt_space_cache || + strcmp(args[0].from, "v1") == 0) { + btrfs_clear_opt(root->fs_info->mount_opt, + FREE_SPACE_TREE); + btrfs_set_and_info(root, SPACE_CACHE, + "enabling disk space caching"); + } else if (strcmp(args[0].from, "v2") == 0) { + btrfs_clear_opt(root->fs_info->mount_opt, + SPACE_CACHE); + btrfs_set_and_info(root, FREE_SPACE_TREE, + "enabling free space tree"); + } else { + ret = -EINVAL; + goto out; + } break; case Opt_rescan_uuid_tree: btrfs_set_opt(info->mount_opt, RESCAN_UUID_TREE); break; case Opt_no_space_cache: - btrfs_clear_and_info(root, SPACE_CACHE, - "disabling disk space caching"); + if (btrfs_test_opt(root, SPACE_CACHE)) { + btrfs_clear_and_info(root, SPACE_CACHE, + "disabling disk space caching"); + } + if (btrfs_test_opt(root, FREE_SPACE_TREE)) { + btrfs_clear_and_info(root, FREE_SPACE_TREE, + "disabling free space tree"); + } break; case Opt_inode_cache: btrfs_set_pending_and_info(info, INODE_MAP_CACHE, @@ -754,8 +778,17 @@ int btrfs_parse_options(struct btrfs_root *root, char *options) } } out: + if (btrfs_fs_compat_ro(root->fs_info, FREE_SPACE_TREE) && + !btrfs_test_opt(root, FREE_SPACE_TREE) && + !btrfs_test_opt(root, CLEAR_CACHE)) { + btrfs_err(root->fs_info, "cannot disable free space tree"); + ret = -EINVAL; + + } if (!ret && btrfs_test_opt(root, SPACE_CACHE)) btrfs_info(root->fs_info, "disk space caching is enabled"); + if (!ret && btrfs_test_opt(root, FREE_SPACE_TREE)) + btrfs_info(root->fs_info, "using free space tree"); kfree(orig); return ret; } @@ -1162,6 +1195,8 @@ static int btrfs_show_options(struct seq_file *seq, struct dentry *dentry) seq_puts(seq, ",noacl"); if (btrfs_test_opt(root, SPACE_CACHE)) seq_puts(seq, ",space_cache"); + else if (btrfs_test_opt(root, FREE_SPACE_TREE)) + seq_puts(seq, ",space_cache=v2"); else seq_puts(seq, ",nospace_cache"); if (btrfs_test_opt(root, RESCAN_UUID_TREE)) @@ -2225,6 +2260,9 @@ static int btrfs_run_sanity_tests(void) if (ret) goto out; ret = btrfs_test_qgroups(); + if (ret) + goto out; + ret = btrfs_test_free_space_tree(); out: btrfs_destroy_test_fs(); return ret; diff --git a/fs/btrfs/tests/btrfs-tests.c b/fs/btrfs/tests/btrfs-tests.c index 9626252ee6b4..b1d920b30070 100644 --- a/fs/btrfs/tests/btrfs-tests.c +++ b/fs/btrfs/tests/btrfs-tests.c @@ -21,6 +21,9 @@ #include #include "btrfs-tests.h" #include "../ctree.h" +#include "../free-space-cache.h" +#include "../free-space-tree.h" +#include "../transaction.h" #include "../volumes.h" #include "../disk-io.h" #include "../qgroup.h" @@ -122,6 +125,9 @@ struct btrfs_fs_info *btrfs_alloc_dummy_fs_info(void) INIT_LIST_HEAD(&fs_info->tree_mod_seq_list); INIT_RADIX_TREE(&fs_info->buffer_radix, GFP_ATOMIC); INIT_RADIX_TREE(&fs_info->fs_roots_radix, GFP_ATOMIC); + extent_io_tree_init(&fs_info->freed_extents[0], NULL); + extent_io_tree_init(&fs_info->freed_extents[1], NULL); + fs_info->pinned_extents = &fs_info->freed_extents[0]; return fs_info; } @@ -169,3 +175,55 @@ void btrfs_free_dummy_root(struct btrfs_root *root) kfree(root); } +struct btrfs_block_group_cache * +btrfs_alloc_dummy_block_group(unsigned long length) +{ + struct btrfs_block_group_cache *cache; + + cache = kzalloc(sizeof(*cache), GFP_NOFS); + if (!cache) + return NULL; + cache->free_space_ctl = kzalloc(sizeof(*cache->free_space_ctl), + GFP_NOFS); + if (!cache->free_space_ctl) { + kfree(cache); + return NULL; + } + cache->fs_info = btrfs_alloc_dummy_fs_info(); + if (!cache->fs_info) { + kfree(cache->free_space_ctl); + kfree(cache); + return NULL; + } + + cache->key.objectid = 0; + cache->key.offset = length; + cache->key.type = BTRFS_BLOCK_GROUP_ITEM_KEY; + cache->sectorsize = 4096; + cache->full_stripe_len = 4096; + + INIT_LIST_HEAD(&cache->list); + INIT_LIST_HEAD(&cache->cluster_list); + INIT_LIST_HEAD(&cache->bg_list); + btrfs_init_free_space_ctl(cache); + mutex_init(&cache->free_space_lock); + + return cache; +} + +void btrfs_free_dummy_block_group(struct btrfs_block_group_cache *cache) +{ + if (!cache) + return; + __btrfs_remove_free_space_cache(cache->free_space_ctl); + kfree(cache->free_space_ctl); + kfree(cache); +} + +void btrfs_init_dummy_trans(struct btrfs_trans_handle *trans) +{ + memset(trans, 0, sizeof(*trans)); + trans->transid = 1; + INIT_LIST_HEAD(&trans->qgroup_ref_list); + trans->type = __TRANS_DUMMY; +} diff --git a/fs/btrfs/tests/btrfs-tests.h b/fs/btrfs/tests/btrfs-tests.h index fd3954224480..054b8c73c951 100644 --- a/fs/btrfs/tests/btrfs-tests.h +++ b/fs/btrfs/tests/btrfs-tests.h @@ -24,17 +24,23 @@ #define test_msg(fmt, ...) pr_info("BTRFS: selftest: " fmt, ##__VA_ARGS__) struct btrfs_root; +struct btrfs_trans_handle; int btrfs_test_free_space_cache(void); int btrfs_test_extent_buffer_operations(void); int btrfs_test_extent_io(void); int btrfs_test_inodes(void); int btrfs_test_qgroups(void); +int btrfs_test_free_space_tree(void); int btrfs_init_test_fs(void); void btrfs_destroy_test_fs(void); struct inode *btrfs_new_test_inode(void); struct btrfs_fs_info *btrfs_alloc_dummy_fs_info(void); void btrfs_free_dummy_root(struct btrfs_root *root); +struct btrfs_block_group_cache * +btrfs_alloc_dummy_block_group(unsigned long length); +void btrfs_free_dummy_block_group(struct btrfs_block_group_cache *cache); +void btrfs_init_dummy_trans(struct btrfs_trans_handle *trans); #else static inline int btrfs_test_free_space_cache(void) { @@ -63,6 +69,10 @@ static inline int btrfs_test_qgroups(void) { return 0; } +static inline int btrfs_test_free_space_tree(void) +{ + return 0; +} #endif #endif diff --git a/fs/btrfs/tests/extent-io-tests.c b/fs/btrfs/tests/extent-io-tests.c index 9e9f2368177d..71ab575e7633 100644 --- a/fs/btrfs/tests/extent-io-tests.c +++ b/fs/btrfs/tests/extent-io-tests.c @@ -18,6 +18,7 @@ #include #include +#include #include "btrfs-tests.h" #include "../extent_io.h" @@ -76,6 +77,8 @@ static int test_find_delalloc(void) u64 found; int ret = -EINVAL; + test_msg("Running find delalloc tests\n"); + inode = btrfs_new_test_inode(); if (!inode) { test_msg("Failed to allocate test inode\n"); @@ -268,8 +271,139 @@ out: return ret; } +static int __test_eb_bitmaps(unsigned long *bitmap, struct extent_buffer *eb, + unsigned long len) +{ + unsigned long i, x; + + memset(bitmap, 0, len); + memset_extent_buffer(eb, 0, 0, len); + if (memcmp_extent_buffer(eb, bitmap, 0, len) != 0) { + test_msg("Bitmap was not zeroed\n"); + return -EINVAL; + } + + bitmap_set(bitmap, 0, len * BITS_PER_BYTE); + extent_buffer_bitmap_set(eb, 0, 0, len * BITS_PER_BYTE); + if (memcmp_extent_buffer(eb, bitmap, 0, len) != 0) { + test_msg("Setting all bits failed\n"); + return -EINVAL; + } + + bitmap_clear(bitmap, 0, len * BITS_PER_BYTE); + extent_buffer_bitmap_clear(eb, 0, 0, len * BITS_PER_BYTE); + if (memcmp_extent_buffer(eb, bitmap, 0, len) != 0) { + test_msg("Clearing all bits failed\n"); + return -EINVAL; + } + + bitmap_set(bitmap, (PAGE_CACHE_SIZE - sizeof(long) / 2) * BITS_PER_BYTE, + sizeof(long) * BITS_PER_BYTE); + extent_buffer_bitmap_set(eb, PAGE_CACHE_SIZE - sizeof(long) / 2, 0, + sizeof(long) * BITS_PER_BYTE); + if (memcmp_extent_buffer(eb, bitmap, 0, len) != 0) { + test_msg("Setting straddling pages failed\n"); + return -EINVAL; + } + + bitmap_set(bitmap, 0, len * BITS_PER_BYTE); + bitmap_clear(bitmap, + (PAGE_CACHE_SIZE - sizeof(long) / 2) * BITS_PER_BYTE, + sizeof(long) * BITS_PER_BYTE); + extent_buffer_bitmap_set(eb, 0, 0, len * BITS_PER_BYTE); + extent_buffer_bitmap_clear(eb, PAGE_CACHE_SIZE - sizeof(long) / 2, 0, + sizeof(long) * BITS_PER_BYTE); + if (memcmp_extent_buffer(eb, bitmap, 0, len) != 0) { + test_msg("Clearing straddling pages failed\n"); + return -EINVAL; + } + + /* + * Generate a wonky pseudo-random bit pattern for the sake of not using + * something repetitive that could miss some hypothetical off-by-n bug. + */ + x = 0; + for (i = 0; i < len / sizeof(long); i++) { + x = (0x19660dULL * (u64)x + 0x3c6ef35fULL) & 0xffffffffUL; + bitmap[i] = x; + } + write_extent_buffer(eb, bitmap, 0, len); + + for (i = 0; i < len * BITS_PER_BYTE; i++) { + int bit, bit1; + + bit = !!test_bit(i, bitmap); + bit1 = !!extent_buffer_test_bit(eb, 0, i); + if (bit1 != bit) { + test_msg("Testing bit pattern failed\n"); + return -EINVAL; + } + + bit1 = !!extent_buffer_test_bit(eb, i / BITS_PER_BYTE, + i % BITS_PER_BYTE); + if (bit1 != bit) { + test_msg("Testing bit pattern with offset failed\n"); + return -EINVAL; + } + } + + return 0; +} + +static int test_eb_bitmaps(void) +{ + unsigned long len = PAGE_CACHE_SIZE * 4; + unsigned long *bitmap; + struct extent_buffer *eb; + int ret; + + test_msg("Running extent buffer bitmap tests\n"); + + bitmap = kmalloc(len, GFP_NOFS); + if (!bitmap) { + test_msg("Couldn't allocate test bitmap\n"); + return -ENOMEM; + } + + eb = __alloc_dummy_extent_buffer(NULL, 0, len); + if (!eb) { + test_msg("Couldn't allocate test extent buffer\n"); + kfree(bitmap); + return -ENOMEM; + } + + ret = __test_eb_bitmaps(bitmap, eb, len); + if (ret) + goto out; + + /* Do it over again with an extent buffer which isn't page-aligned. */ + free_extent_buffer(eb); + eb = __alloc_dummy_extent_buffer(NULL, PAGE_CACHE_SIZE / 2, len); + if (!eb) { + test_msg("Couldn't allocate test extent buffer\n"); + kfree(bitmap); + return -ENOMEM; + } + + ret = __test_eb_bitmaps(bitmap, eb, len); +out: + free_extent_buffer(eb); + kfree(bitmap); + return ret; +} + int btrfs_test_extent_io(void) { - test_msg("Running find delalloc tests\n"); - return test_find_delalloc(); + int ret; + + test_msg("Running extent I/O tests\n"); + + ret = test_find_delalloc(); + if (ret) + goto out; + + ret = test_eb_bitmaps(); +out: + test_msg("Extent I/O tests finished\n"); + return ret; } diff --git a/fs/btrfs/tests/free-space-tests.c b/fs/btrfs/tests/free-space-tests.c index 8b72b005bfb9..cd3e300b9ba5 100644 --- a/fs/btrfs/tests/free-space-tests.c +++ b/fs/btrfs/tests/free-space-tests.c @@ -23,41 +23,6 @@ #include "../free-space-cache.h" #define BITS_PER_BITMAP (PAGE_CACHE_SIZE * 8) -static struct btrfs_block_group_cache *init_test_block_group(void) -{ - struct btrfs_block_group_cache *cache; - - cache = kzalloc(sizeof(*cache), GFP_NOFS); - if (!cache) - return NULL; - cache->free_space_ctl = kzalloc(sizeof(*cache->free_space_ctl), - GFP_NOFS); - if (!cache->free_space_ctl) { - kfree(cache); - return NULL; - } - cache->fs_info = btrfs_alloc_dummy_fs_info(); - if (!cache->fs_info) { - kfree(cache->free_space_ctl); - kfree(cache); - return NULL; - } - - cache->key.objectid = 0; - cache->key.offset = 1024 * 1024 * 1024; - cache->key.type = BTRFS_BLOCK_GROUP_ITEM_KEY; - cache->sectorsize = 4096; - cache->full_stripe_len = 4096; - - spin_lock_init(&cache->lock); - INIT_LIST_HEAD(&cache->list); - INIT_LIST_HEAD(&cache->cluster_list); - INIT_LIST_HEAD(&cache->bg_list); - - btrfs_init_free_space_ctl(cache); - - return cache; -} /* * This test just does basic sanity checking, making sure we can add an exten @@ -891,7 +856,7 @@ int btrfs_test_free_space_cache(void) test_msg("Running btrfs free space cache tests\n"); - cache = init_test_block_group(); + cache = btrfs_alloc_dummy_block_group(1024 * 1024 * 1024); if (!cache) { test_msg("Couldn't run the tests\n"); return 0; @@ -922,9 +887,7 @@ int btrfs_test_free_space_cache(void) ret = test_steal_space_from_bitmap_to_extent(cache); out: - __btrfs_remove_free_space_cache(cache->free_space_ctl); - kfree(cache->free_space_ctl); - kfree(cache); + btrfs_free_dummy_block_group(cache); btrfs_free_dummy_root(root); test_msg("Free space cache tests finished\n"); return ret; diff --git a/fs/btrfs/tests/free-space-tree-tests.c b/fs/btrfs/tests/free-space-tree-tests.c new file mode 100644 index 000000000000..d05fe1ab4808 --- /dev/null +++ b/fs/btrfs/tests/free-space-tree-tests.c @@ -0,0 +1,571 @@ +/* + * Copyright (C) 2015 Facebook. All rights reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public + * License v2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public + * License along with this program; if not, write to the + * Free Software Foundation, Inc., 59 Temple Place - Suite 330, + * Boston, MA 021110-1307, USA. + */ + +#include "btrfs-tests.h" +#include "../ctree.h" +#include "../disk-io.h" +#include "../free-space-tree.h" +#include "../transaction.h" + +struct free_space_extent { + u64 start, length; +}; + +/* + * The test cases align their operations to this in order to hit some of the + * edge cases in the bitmap code. + */ +#define BITMAP_RANGE (BTRFS_FREE_SPACE_BITMAP_BITS * 4096) + +static int __check_free_space_extents(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + struct btrfs_block_group_cache *cache, + struct btrfs_path *path, + struct free_space_extent *extents, + unsigned int num_extents) +{ + struct btrfs_free_space_info *info; + struct btrfs_key key; + int prev_bit = 0, bit; + u64 extent_start = 0, offset, end; + u32 flags, extent_count; + unsigned int i; + int ret; + + info = search_free_space_info(trans, fs_info, cache, path, 0); + if (IS_ERR(info)) { + test_msg("Could not find free space info\n"); + ret = PTR_ERR(info); + goto out; + } + flags = btrfs_free_space_flags(path->nodes[0], info); + extent_count = btrfs_free_space_extent_count(path->nodes[0], info); + + if (extent_count != num_extents) { + test_msg("Extent count is wrong\n"); + ret = -EINVAL; + goto out; + } + if (flags & BTRFS_FREE_SPACE_USING_BITMAPS) { + if (path->slots[0] != 0) + goto invalid; + end = cache->key.objectid + cache->key.offset; + i = 0; + while (++path->slots[0] < btrfs_header_nritems(path->nodes[0])) { + btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); + if (key.type != BTRFS_FREE_SPACE_BITMAP_KEY) + goto invalid; + offset = key.objectid; + while (offset < key.objectid + key.offset) { + bit = free_space_test_bit(cache, path, offset); + if (prev_bit == 0 && bit == 1) { + extent_start = offset; + } else if (prev_bit == 1 && bit == 0) { + if (i >= num_extents) + goto invalid; + if (i >= num_extents || + extent_start != extents[i].start || + offset - extent_start != extents[i].length) + goto invalid; + i++; + } + prev_bit = bit; + offset += cache->sectorsize; + } + } + if (prev_bit == 1) { + if (i >= num_extents || + extent_start != extents[i].start || + end - extent_start != extents[i].length) + goto invalid; + i++; + } + if (i != num_extents) + goto invalid; + } else { + if (btrfs_header_nritems(path->nodes[0]) != num_extents + 1 || + path->slots[0] != 0) + goto invalid; + for (i = 0; i < num_extents; i++) { + path->slots[0]++; + btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]); + if (key.type != BTRFS_FREE_SPACE_EXTENT_KEY || + key.objectid != extents[i].start || + key.offset != extents[i].length) + goto invalid; + } + } + + ret = 0; +out: + btrfs_release_path(path); + return ret; +invalid: + test_msg("Free space tree is invalid\n"); + ret = -EINVAL; + goto out; +} + +static int check_free_space_extents(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + struct btrfs_block_group_cache *cache, + struct btrfs_path *path, + struct free_space_extent *extents, + unsigned int num_extents) +{ + struct btrfs_free_space_info *info; + u32 flags; + int ret; + + info = search_free_space_info(trans, fs_info, cache, path, 0); + if (IS_ERR(info)) { + test_msg("Could not find free space info\n"); + btrfs_release_path(path); + return PTR_ERR(info); + } + flags = btrfs_free_space_flags(path->nodes[0], info); + btrfs_release_path(path); + + ret = __check_free_space_extents(trans, fs_info, cache, path, extents, + num_extents); + if (ret) + return ret; + + /* Flip it to the other format and check that for good measure. */ + if (flags & BTRFS_FREE_SPACE_USING_BITMAPS) { + ret = convert_free_space_to_extents(trans, fs_info, cache, path); + if (ret) { + test_msg("Could not convert to extents\n"); + return ret; + } + } else { + ret = convert_free_space_to_bitmaps(trans, fs_info, cache, path); + if (ret) { + test_msg("Could not convert to bitmaps\n"); + return ret; + } + } + return __check_free_space_extents(trans, fs_info, cache, path, extents, + num_extents); +} + +static int test_empty_block_group(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + struct btrfs_block_group_cache *cache, + struct btrfs_path *path) +{ + struct free_space_extent extents[] = { + {cache->key.objectid, cache->key.offset}, + }; + + return check_free_space_extents(trans, fs_info, cache, path, + extents, ARRAY_SIZE(extents)); +} + +static int test_remove_all(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + struct btrfs_block_group_cache *cache, + struct btrfs_path *path) +{ + struct free_space_extent extents[] = {}; + int ret; + + ret = __remove_from_free_space_tree(trans, fs_info, cache, path, + cache->key.objectid, + cache->key.offset); + if (ret) { + test_msg("Could not remove free space\n"); + return ret; + } + + return check_free_space_extents(trans, fs_info, cache, path, + extents, ARRAY_SIZE(extents)); +} + +static int test_remove_beginning(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + struct btrfs_block_group_cache *cache, + struct btrfs_path *path) +{ + struct free_space_extent extents[] = { + {cache->key.objectid + BITMAP_RANGE, + cache->key.offset - BITMAP_RANGE}, + }; + int ret; + + ret = __remove_from_free_space_tree(trans, fs_info, cache, path, + cache->key.objectid, BITMAP_RANGE); + if (ret) { + test_msg("Could not remove free space\n"); + return ret; + } + + return check_free_space_extents(trans, fs_info, cache, path, + extents, ARRAY_SIZE(extents)); + +} + +static int test_remove_end(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + struct btrfs_block_group_cache *cache, + struct btrfs_path *path) +{ + struct free_space_extent extents[] = { + {cache->key.objectid, cache->key.offset - BITMAP_RANGE}, + }; + int ret; + + ret = __remove_from_free_space_tree(trans, fs_info, cache, path, + cache->key.objectid + + cache->key.offset - BITMAP_RANGE, + BITMAP_RANGE); + if (ret) { + test_msg("Could not remove free space\n"); + return ret; + } + + return check_free_space_extents(trans, fs_info, cache, path, + extents, ARRAY_SIZE(extents)); +} + +static int test_remove_middle(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + struct btrfs_block_group_cache *cache, + struct btrfs_path *path) +{ + struct free_space_extent extents[] = { + {cache->key.objectid, BITMAP_RANGE}, + {cache->key.objectid + 2 * BITMAP_RANGE, + cache->key.offset - 2 * BITMAP_RANGE}, + }; + int ret; + + ret = __remove_from_free_space_tree(trans, fs_info, cache, path, + cache->key.objectid + BITMAP_RANGE, + BITMAP_RANGE); + if (ret) { + test_msg("Could not remove free space\n"); + return ret; + } + + return check_free_space_extents(trans, fs_info, cache, path, + extents, ARRAY_SIZE(extents)); +} + +static int test_merge_left(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + struct btrfs_block_group_cache *cache, + struct btrfs_path *path) +{ + struct free_space_extent extents[] = { + {cache->key.objectid, 2 * BITMAP_RANGE}, + }; + int ret; + + ret = __remove_from_free_space_tree(trans, fs_info, cache, path, + cache->key.objectid, + cache->key.offset); + if (ret) { + test_msg("Could not remove free space\n"); + return ret; + } + + ret = __add_to_free_space_tree(trans, fs_info, cache, path, + cache->key.objectid, BITMAP_RANGE); + if (ret) { + test_msg("Could not add free space\n"); + return ret; + } + + ret = __add_to_free_space_tree(trans, fs_info, cache, path, + cache->key.objectid + BITMAP_RANGE, + BITMAP_RANGE); + if (ret) { + test_msg("Could not add free space\n"); + return ret; + } + + return check_free_space_extents(trans, fs_info, cache, path, + extents, ARRAY_SIZE(extents)); +} + +static int test_merge_right(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + struct btrfs_block_group_cache *cache, + struct btrfs_path *path) +{ + struct free_space_extent extents[] = { + {cache->key.objectid + BITMAP_RANGE, 2 * BITMAP_RANGE}, + }; + int ret; + + ret = __remove_from_free_space_tree(trans, fs_info, cache, path, + cache->key.objectid, + cache->key.offset); + if (ret) { + test_msg("Could not remove free space\n"); + return ret; + } + + ret = __add_to_free_space_tree(trans, fs_info, cache, path, + cache->key.objectid + 2 * BITMAP_RANGE, + BITMAP_RANGE); + if (ret) { + test_msg("Could not add free space\n"); + return ret; + } + + ret = __add_to_free_space_tree(trans, fs_info, cache, path, + cache->key.objectid + BITMAP_RANGE, + BITMAP_RANGE); + if (ret) { + test_msg("Could not add free space\n"); + return ret; + } + + return check_free_space_extents(trans, fs_info, cache, path, + extents, ARRAY_SIZE(extents)); +} + +static int test_merge_both(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + struct btrfs_block_group_cache *cache, + struct btrfs_path *path) +{ + struct free_space_extent extents[] = { + {cache->key.objectid, 3 * BITMAP_RANGE}, + }; + int ret; + + ret = __remove_from_free_space_tree(trans, fs_info, cache, path, + cache->key.objectid, + cache->key.offset); + if (ret) { + test_msg("Could not remove free space\n"); + return ret; + } + + ret = __add_to_free_space_tree(trans, fs_info, cache, path, + cache->key.objectid, BITMAP_RANGE); + if (ret) { + test_msg("Could not add free space\n"); + return ret; + } + + ret = __add_to_free_space_tree(trans, fs_info, cache, path, + cache->key.objectid + 2 * BITMAP_RANGE, + BITMAP_RANGE); + if (ret) { + test_msg("Could not add free space\n"); + return ret; + } + + ret = __add_to_free_space_tree(trans, fs_info, cache, path, + cache->key.objectid + BITMAP_RANGE, + BITMAP_RANGE); + if (ret) { + test_msg("Could not add free space\n"); + return ret; + } + + return check_free_space_extents(trans, fs_info, cache, path, + extents, ARRAY_SIZE(extents)); +} + +static int test_merge_none(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + struct btrfs_block_group_cache *cache, + struct btrfs_path *path) +{ + struct free_space_extent extents[] = { + {cache->key.objectid, BITMAP_RANGE}, + {cache->key.objectid + 2 * BITMAP_RANGE, BITMAP_RANGE}, + {cache->key.objectid + 4 * BITMAP_RANGE, BITMAP_RANGE}, + }; + int ret; + + ret = __remove_from_free_space_tree(trans, fs_info, cache, path, + cache->key.objectid, + cache->key.offset); + if (ret) { + test_msg("Could not remove free space\n"); + return ret; + } + + ret = __add_to_free_space_tree(trans, fs_info, cache, path, + cache->key.objectid, BITMAP_RANGE); + if (ret) { + test_msg("Could not add free space\n"); + return ret; + } + + ret = __add_to_free_space_tree(trans, fs_info, cache, path, + cache->key.objectid + 4 * BITMAP_RANGE, + BITMAP_RANGE); + if (ret) { + test_msg("Could not add free space\n"); + return ret; + } + + ret = __add_to_free_space_tree(trans, fs_info, cache, path, + cache->key.objectid + 2 * BITMAP_RANGE, + BITMAP_RANGE); + if (ret) { + test_msg("Could not add free space\n"); + return ret; + } + + return check_free_space_extents(trans, fs_info, cache, path, + extents, ARRAY_SIZE(extents)); +} + +typedef int (*test_func_t)(struct btrfs_trans_handle *, + struct btrfs_fs_info *, + struct btrfs_block_group_cache *, + struct btrfs_path *); + +static int run_test(test_func_t test_func, int bitmaps) +{ + struct btrfs_root *root = NULL; + struct btrfs_block_group_cache *cache = NULL; + struct btrfs_trans_handle trans; + struct btrfs_path *path = NULL; + int ret; + + root = btrfs_alloc_dummy_root(); + if (IS_ERR(root)) { + test_msg("Couldn't allocate dummy root\n"); + ret = PTR_ERR(root); + goto out; + } + + root->fs_info = btrfs_alloc_dummy_fs_info(); + if (!root->fs_info) { + test_msg("Couldn't allocate dummy fs info\n"); + ret = -ENOMEM; + goto out; + } + + btrfs_set_super_compat_ro_flags(root->fs_info->super_copy, + BTRFS_FEATURE_COMPAT_RO_FREE_SPACE_TREE); + root->fs_info->free_space_root = root; + root->fs_info->tree_root = root; + + root->node = alloc_test_extent_buffer(root->fs_info, 4096); + if (!root->node) { + test_msg("Couldn't allocate dummy buffer\n"); + ret = -ENOMEM; + goto out; + } + btrfs_set_header_level(root->node, 0); + btrfs_set_header_nritems(root->node, 0); + root->alloc_bytenr += 8192; + + cache = btrfs_alloc_dummy_block_group(8 * BITMAP_RANGE); + if (!cache) { + test_msg("Couldn't allocate dummy block group cache\n"); + ret = -ENOMEM; + goto out; + } + cache->bitmap_low_thresh = 0; + cache->bitmap_high_thresh = (u32)-1; + cache->needs_free_space = 1; + + btrfs_init_dummy_trans(&trans); + + path = btrfs_alloc_path(); + if (!path) { + test_msg("Couldn't allocate path\n"); + return -ENOMEM; + } + + ret = add_block_group_free_space(&trans, root->fs_info, cache); + if (ret) { + test_msg("Could not add block group free space\n"); + goto out; + } + + if (bitmaps) { + ret = convert_free_space_to_bitmaps(&trans, root->fs_info, + cache, path); + if (ret) { + test_msg("Could not convert block group to bitmaps\n"); + goto out; + } + } + + ret = test_func(&trans, root->fs_info, cache, path); + if (ret) + goto out; + + ret = remove_block_group_free_space(&trans, root->fs_info, cache); + if (ret) { + test_msg("Could not remove block group free space\n"); + goto out; + } + + if (btrfs_header_nritems(root->node) != 0) { + test_msg("Free space tree has leftover items\n"); + ret = -EINVAL; + goto out; + } + + ret = 0; +out: + btrfs_free_path(path); + btrfs_free_dummy_block_group(cache); + btrfs_free_dummy_root(root); + return ret; +} + +static int run_test_both_formats(test_func_t test_func) +{ + int ret; + + ret = run_test(test_func, 0); + if (ret) + return ret; + return run_test(test_func, 1); +} + +int btrfs_test_free_space_tree(void) +{ + test_func_t tests[] = { + test_empty_block_group, + test_remove_all, + test_remove_beginning, + test_remove_end, + test_remove_middle, + test_merge_left, + test_merge_right, + test_merge_both, + test_merge_none, + }; + int i; + + test_msg("Running free space tree tests\n"); + for (i = 0; i < ARRAY_SIZE(tests); i++) { + int ret = run_test_both_formats(tests[i]); + if (ret) { + test_msg("%pf failed\n", tests[i]); + return ret; + } + } + + return 0; +} diff --git a/fs/btrfs/tests/qgroup-tests.c b/fs/btrfs/tests/qgroup-tests.c index 846d277b1901..8ea5d34bc5a2 100644 --- a/fs/btrfs/tests/qgroup-tests.c +++ b/fs/btrfs/tests/qgroup-tests.c @@ -23,14 +23,6 @@ #include "../qgroup.h" #include "../backref.h" -static void init_dummy_trans(struct btrfs_trans_handle *trans) -{ - memset(trans, 0, sizeof(*trans)); - trans->transid = 1; - INIT_LIST_HEAD(&trans->qgroup_ref_list); - trans->type = __TRANS_DUMMY; -} - static int insert_normal_tree_ref(struct btrfs_root *root, u64 bytenr, u64 num_bytes, u64 parent, u64 root_objectid) { @@ -44,7 +36,7 @@ static int insert_normal_tree_ref(struct btrfs_root *root, u64 bytenr, u32 size = sizeof(*item) + sizeof(*iref) + sizeof(*block_info); int ret; - init_dummy_trans(&trans); + btrfs_init_dummy_trans(&trans); ins.objectid = bytenr; ins.type = BTRFS_EXTENT_ITEM_KEY; @@ -94,7 +86,7 @@ static int add_tree_ref(struct btrfs_root *root, u64 bytenr, u64 num_bytes, u64 refs; int ret; - init_dummy_trans(&trans); + btrfs_init_dummy_trans(&trans); key.objectid = bytenr; key.type = BTRFS_EXTENT_ITEM_KEY; @@ -144,7 +136,7 @@ static int remove_extent_item(struct btrfs_root *root, u64 bytenr, struct btrfs_path *path; int ret; - init_dummy_trans(&trans); + btrfs_init_dummy_trans(&trans); key.objectid = bytenr; key.type = BTRFS_EXTENT_ITEM_KEY; @@ -178,7 +170,7 @@ static int remove_extent_ref(struct btrfs_root *root, u64 bytenr, u64 refs; int ret; - init_dummy_trans(&trans); + btrfs_init_dummy_trans(&trans); key.objectid = bytenr; key.type = BTRFS_EXTENT_ITEM_KEY; @@ -232,7 +224,7 @@ static int test_no_shared_qgroup(struct btrfs_root *root) struct ulist *new_roots = NULL; int ret; - init_dummy_trans(&trans); + btrfs_init_dummy_trans(&trans); test_msg("Qgroup basic add\n"); ret = btrfs_create_qgroup(NULL, fs_info, 5); @@ -326,7 +318,7 @@ static int test_multiple_refs(struct btrfs_root *root) struct ulist *new_roots = NULL; int ret; - init_dummy_trans(&trans); + btrfs_init_dummy_trans(&trans); test_msg("Qgroup multiple refs test\n"); diff --git a/include/trace/events/btrfs.h b/include/trace/events/btrfs.h index b4473dab39d6..d866f21efbbf 100644 --- a/include/trace/events/btrfs.h +++ b/include/trace/events/btrfs.h @@ -45,7 +45,8 @@ struct btrfs_qgroup_operation; { BTRFS_TREE_LOG_OBJECTID, "TREE_LOG" }, \ { BTRFS_QUOTA_TREE_OBJECTID, "QUOTA_TREE" }, \ { BTRFS_TREE_RELOC_OBJECTID, "TREE_RELOC" }, \ - { BTRFS_UUID_TREE_OBJECTID, "UUID_RELOC" }, \ + { BTRFS_UUID_TREE_OBJECTID, "UUID_TREE" }, \ + { BTRFS_FREE_SPACE_TREE_OBJECTID, "FREE_SPACE_TREE" }, \ { BTRFS_DATA_RELOC_TREE_OBJECTID, "DATA_RELOC_TREE" }) #define show_root_type(obj) \