diff options
Diffstat (limited to 'fs/btrfs/backref.c')
-rw-r--r-- | fs/btrfs/backref.c | 126 |
1 files changed, 72 insertions, 54 deletions
diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c index 633c701a287d..f4e90748940a 100644 --- a/fs/btrfs/backref.c +++ b/fs/btrfs/backref.c @@ -116,6 +116,7 @@ add_parent: * to a logical address */ static int __resolve_indirect_ref(struct btrfs_fs_info *fs_info, + int search_commit_root, struct __prelim_ref *ref, struct ulist *parents) { @@ -131,6 +132,7 @@ static int __resolve_indirect_ref(struct btrfs_fs_info *fs_info, path = btrfs_alloc_path(); if (!path) return -ENOMEM; + path->search_commit_root = !!search_commit_root; root_key.objectid = ref->root_id; root_key.type = BTRFS_ROOT_ITEM_KEY; @@ -188,6 +190,7 @@ out: * resolve all indirect backrefs from the list */ static int __resolve_indirect_refs(struct btrfs_fs_info *fs_info, + int search_commit_root, struct list_head *head) { int err; @@ -212,7 +215,8 @@ static int __resolve_indirect_refs(struct btrfs_fs_info *fs_info, continue; if (ref->count == 0) continue; - err = __resolve_indirect_ref(fs_info, ref, parents); + err = __resolve_indirect_ref(fs_info, search_commit_root, + ref, parents); if (err) { if (ret == 0) ret = err; @@ -583,9 +587,10 @@ static int find_parent_nodes(struct btrfs_trans_handle *trans, struct btrfs_path *path; struct btrfs_key info_key = { 0 }; struct btrfs_delayed_ref_root *delayed_refs = NULL; - struct btrfs_delayed_ref_head *head = NULL; + struct btrfs_delayed_ref_head *head; int info_level = 0; int ret; + int search_commit_root = (trans == BTRFS_BACKREF_SEARCH_COMMIT_ROOT); struct list_head prefs_delayed; struct list_head prefs; struct __prelim_ref *ref; @@ -600,6 +605,7 @@ static int find_parent_nodes(struct btrfs_trans_handle *trans, path = btrfs_alloc_path(); if (!path) return -ENOMEM; + path->search_commit_root = !!search_commit_root; /* * grab both a lock on the path and a lock on the delayed ref head. @@ -607,38 +613,46 @@ static int find_parent_nodes(struct btrfs_trans_handle *trans, * at a specified point in time */ again: + head = NULL; + ret = btrfs_search_slot(trans, fs_info->extent_root, &key, path, 0, 0); if (ret < 0) goto out; BUG_ON(ret == 0); - /* - * look if there are updates for this ref queued and lock the head - */ - delayed_refs = &trans->transaction->delayed_refs; - spin_lock(&delayed_refs->lock); - head = btrfs_find_delayed_ref_head(trans, bytenr); - if (head) { - if (!mutex_trylock(&head->mutex)) { - atomic_inc(&head->node.refs); - spin_unlock(&delayed_refs->lock); - - btrfs_release_path(path); - - /* - * Mutex was contended, block until it's - * released and try again - */ - mutex_lock(&head->mutex); - mutex_unlock(&head->mutex); - btrfs_put_delayed_ref(&head->node); - goto again; + if (trans != BTRFS_BACKREF_SEARCH_COMMIT_ROOT) { + /* + * look if there are updates for this ref queued and lock the + * head + */ + delayed_refs = &trans->transaction->delayed_refs; + spin_lock(&delayed_refs->lock); + head = btrfs_find_delayed_ref_head(trans, bytenr); + if (head) { + if (!mutex_trylock(&head->mutex)) { + atomic_inc(&head->node.refs); + spin_unlock(&delayed_refs->lock); + + btrfs_release_path(path); + + /* + * Mutex was contended, block until it's + * released and try again + */ + mutex_lock(&head->mutex); + mutex_unlock(&head->mutex); + btrfs_put_delayed_ref(&head->node); + goto again; + } + ret = __add_delayed_refs(head, seq, &info_key, + &prefs_delayed); + if (ret) { + spin_unlock(&delayed_refs->lock); + goto out; + } } - ret = __add_delayed_refs(head, seq, &info_key, &prefs_delayed); - if (ret) - goto out; + spin_unlock(&delayed_refs->lock); } - spin_unlock(&delayed_refs->lock); if (path->slots[0]) { struct extent_buffer *leaf; @@ -675,7 +689,7 @@ again: if (ret) goto out; - ret = __resolve_indirect_refs(fs_info, &prefs); + ret = __resolve_indirect_refs(fs_info, search_commit_root, &prefs); if (ret) goto out; @@ -892,6 +906,8 @@ static char *iref_to_path(struct btrfs_root *fs_root, struct btrfs_path *path, if (eb != eb_in) free_extent_buffer(eb); ret = inode_ref_info(parent, 0, fs_root, path, &found_key); + if (ret > 0) + ret = -ENOENT; if (ret) break; next_inum = found_key.offset; @@ -1068,8 +1084,7 @@ int tree_backref_for_extent(unsigned long *ptr, struct extent_buffer *eb, return 0; } -static int iterate_leaf_refs(struct btrfs_fs_info *fs_info, - struct btrfs_path *path, u64 logical, +static int iterate_leaf_refs(struct btrfs_fs_info *fs_info, u64 logical, u64 orig_extent_item_objectid, u64 extent_item_pos, u64 root, iterate_extent_inodes_t *iterate, void *ctx) @@ -1137,35 +1152,38 @@ static int iterate_leaf_refs(struct btrfs_fs_info *fs_info, * calls iterate() for every inode that references the extent identified by * the given parameters. * when the iterator function returns a non-zero value, iteration stops. - * path is guaranteed to be in released state when iterate() is called. */ int iterate_extent_inodes(struct btrfs_fs_info *fs_info, - struct btrfs_path *path, u64 extent_item_objectid, u64 extent_item_pos, + int search_commit_root, iterate_extent_inodes_t *iterate, void *ctx) { int ret; struct list_head data_refs = LIST_HEAD_INIT(data_refs); struct list_head shared_refs = LIST_HEAD_INIT(shared_refs); struct btrfs_trans_handle *trans; - struct ulist *refs; - struct ulist *roots; + struct ulist *refs = NULL; + struct ulist *roots = NULL; struct ulist_node *ref_node = NULL; struct ulist_node *root_node = NULL; struct seq_list seq_elem; - struct btrfs_delayed_ref_root *delayed_refs; - - trans = btrfs_join_transaction(fs_info->extent_root); - if (IS_ERR(trans)) - return PTR_ERR(trans); + struct btrfs_delayed_ref_root *delayed_refs = NULL; pr_debug("resolving all inodes for extent %llu\n", extent_item_objectid); - delayed_refs = &trans->transaction->delayed_refs; - spin_lock(&delayed_refs->lock); - btrfs_get_delayed_seq(delayed_refs, &seq_elem); - spin_unlock(&delayed_refs->lock); + if (search_commit_root) { + trans = BTRFS_BACKREF_SEARCH_COMMIT_ROOT; + } else { + trans = btrfs_join_transaction(fs_info->extent_root); + if (IS_ERR(trans)) + return PTR_ERR(trans); + + delayed_refs = &trans->transaction->delayed_refs; + spin_lock(&delayed_refs->lock); + btrfs_get_delayed_seq(delayed_refs, &seq_elem); + spin_unlock(&delayed_refs->lock); + } ret = btrfs_find_all_leafs(trans, fs_info, extent_item_objectid, extent_item_pos, seq_elem.seq, @@ -1182,7 +1200,7 @@ int iterate_extent_inodes(struct btrfs_fs_info *fs_info, while (!ret && (root_node = ulist_next(roots, root_node))) { pr_debug("root %llu references leaf %llu\n", root_node->val, ref_node->val); - ret = iterate_leaf_refs(fs_info, path, ref_node->val, + ret = iterate_leaf_refs(fs_info, ref_node->val, extent_item_objectid, extent_item_pos, root_node->val, iterate, ctx); @@ -1192,8 +1210,11 @@ int iterate_extent_inodes(struct btrfs_fs_info *fs_info, ulist_free(refs); ulist_free(roots); out: - btrfs_put_delayed_seq(delayed_refs, &seq_elem); - btrfs_end_transaction(trans, fs_info->extent_root); + if (!search_commit_root) { + btrfs_put_delayed_seq(delayed_refs, &seq_elem); + btrfs_end_transaction(trans, fs_info->extent_root); + } + return ret; } @@ -1204,6 +1225,7 @@ int iterate_inodes_from_logical(u64 logical, struct btrfs_fs_info *fs_info, int ret; u64 extent_item_pos; struct btrfs_key found_key; + int search_commit_root = path->search_commit_root; ret = extent_from_logical(fs_info, logical, path, &found_key); @@ -1214,8 +1236,9 @@ int iterate_inodes_from_logical(u64 logical, struct btrfs_fs_info *fs_info, return ret; extent_item_pos = logical - found_key.objectid; - ret = iterate_extent_inodes(fs_info, path, found_key.objectid, - extent_item_pos, iterate, ctx); + ret = iterate_extent_inodes(fs_info, found_key.objectid, + extent_item_pos, search_commit_root, + iterate, ctx); return ret; } @@ -1336,12 +1359,6 @@ int paths_from_inode(u64 inum, struct inode_fs_paths *ipath) inode_to_path, ipath); } -/* - * allocates space to return multiple file system paths for an inode. - * total_bytes to allocate are passed, note that space usable for actual path - * information will be total_bytes - sizeof(struct inode_fs_paths). - * the returned pointer must be freed with free_ipath() in the end. - */ struct btrfs_data_container *init_data_container(u32 total_bytes) { struct btrfs_data_container *data; @@ -1397,5 +1414,6 @@ struct inode_fs_paths *init_ipath(s32 total_bytes, struct btrfs_root *fs_root, void free_ipath(struct inode_fs_paths *ipath) { + kfree(ipath->fspath); kfree(ipath); } |