diff options
| -rw-r--r-- | fs/btrfs/btrfs_inode.h | 6 | ||||
| -rw-r--r-- | fs/btrfs/inode.c | 17 | ||||
| -rw-r--r-- | fs/btrfs/tree-log.c | 228 |
3 files changed, 188 insertions, 63 deletions
diff --git a/fs/btrfs/btrfs_inode.h b/fs/btrfs/btrfs_inode.h index b16c13d51be0..d5b438706b77 100644 --- a/fs/btrfs/btrfs_inode.h +++ b/fs/btrfs/btrfs_inode.h @@ -148,12 +148,6 @@ struct btrfs_inode { u64 last_unlink_trans; /* - * Track the transaction id of the last transaction used to create a - * hard link for the inode. This is used by the log tree (fsync). - */ - u64 last_link_trans; - - /* * Number of bytes outstanding that are going to need csums. This is * used in ENOSPC accounting. */ diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index fb237ffbda1a..fcc23e14a86c 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -3689,21 +3689,6 @@ cache_index: * inode is not a directory, logging its parent unnecessarily. */ BTRFS_I(inode)->last_unlink_trans = BTRFS_I(inode)->last_trans; - /* - * Similar reasoning for last_link_trans, needs to be set otherwise - * for a case like the following: - * - * mkdir A - * touch foo - * ln foo A/bar - * echo 2 > /proc/sys/vm/drop_caches - * fsync foo - * <power failure> - * - * Would result in link bar and directory A not existing after the power - * failure. - */ - BTRFS_I(inode)->last_link_trans = BTRFS_I(inode)->last_trans; path->slots[0]++; if (inode->i_nlink != 1 || @@ -6655,7 +6640,6 @@ static int btrfs_link(struct dentry *old_dentry, struct inode *dir, if (err) goto fail; } - BTRFS_I(inode)->last_link_trans = trans->transid; d_instantiate(dentry, inode); ret = btrfs_log_new_name(trans, BTRFS_I(inode), NULL, parent, true, NULL); @@ -9192,7 +9176,6 @@ struct inode *btrfs_alloc_inode(struct super_block *sb) ei->index_cnt = (u64)-1; ei->dir_index = 0; ei->last_unlink_trans = 0; - ei->last_link_trans = 0; ei->last_log_commit = 0; spin_lock_init(&ei->lock); diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c index 67cd144e6be1..6adcd8a2c5c7 100644 --- a/fs/btrfs/tree-log.c +++ b/fs/btrfs/tree-log.c @@ -5832,6 +5832,190 @@ out: return ret; } +static int log_new_ancestors(struct btrfs_trans_handle *trans, + struct btrfs_root *root, + struct btrfs_path *path, + struct btrfs_log_ctx *ctx) +{ + struct btrfs_key found_key; + + btrfs_item_key_to_cpu(path->nodes[0], &found_key, path->slots[0]); + + while (true) { + struct btrfs_fs_info *fs_info = root->fs_info; + const u64 last_committed = fs_info->last_trans_committed; + struct extent_buffer *leaf = path->nodes[0]; + int slot = path->slots[0]; + struct btrfs_key search_key; + struct inode *inode; + int ret = 0; + + btrfs_release_path(path); + + search_key.objectid = found_key.offset; + search_key.type = BTRFS_INODE_ITEM_KEY; + search_key.offset = 0; + inode = btrfs_iget(fs_info->sb, &search_key, root, NULL); + if (IS_ERR(inode)) + return PTR_ERR(inode); + + if (BTRFS_I(inode)->generation > last_committed) + ret = btrfs_log_inode(trans, root, BTRFS_I(inode), + LOG_INODE_EXISTS, + 0, LLONG_MAX, ctx); + iput(inode); + if (ret) + return ret; + + if (search_key.objectid == BTRFS_FIRST_FREE_OBJECTID) + break; + + search_key.type = BTRFS_INODE_REF_KEY; + ret = btrfs_search_slot(NULL, root, &search_key, path, 0, 0); + if (ret < 0) + return ret; + + leaf = path->nodes[0]; + slot = path->slots[0]; + if (slot >= btrfs_header_nritems(leaf)) { + ret = btrfs_next_leaf(root, path); + if (ret < 0) + return ret; + else if (ret > 0) + return -ENOENT; + leaf = path->nodes[0]; + slot = path->slots[0]; + } + + btrfs_item_key_to_cpu(leaf, &found_key, slot); + if (found_key.objectid != search_key.objectid || + found_key.type != BTRFS_INODE_REF_KEY) + return -ENOENT; + } + return 0; +} + +static int log_new_ancestors_fast(struct btrfs_trans_handle *trans, + struct btrfs_inode *inode, + struct dentry *parent, + struct btrfs_log_ctx *ctx) +{ + struct btrfs_root *root = inode->root; + struct btrfs_fs_info *fs_info = root->fs_info; + struct dentry *old_parent = NULL; + struct super_block *sb = inode->vfs_inode.i_sb; + int ret = 0; + + while (true) { + if (!parent || d_really_is_negative(parent) || + sb != parent->d_sb) + break; + + inode = BTRFS_I(d_inode(parent)); + if (root != inode->root) + break; + + if (inode->generation > fs_info->last_trans_committed) { + ret = btrfs_log_inode(trans, root, inode, + LOG_INODE_EXISTS, 0, LLONG_MAX, ctx); + if (ret) + break; + } + if (IS_ROOT(parent)) + break; + + parent = dget_parent(parent); + dput(old_parent); + old_parent = parent; + } + dput(old_parent); + + return ret; +} + +static int log_all_new_ancestors(struct btrfs_trans_handle *trans, + struct btrfs_inode *inode, + struct dentry *parent, + struct btrfs_log_ctx *ctx) +{ + struct btrfs_root *root = inode->root; + const u64 ino = btrfs_ino(inode); + struct btrfs_path *path; + struct btrfs_key search_key; + int ret; + + /* + * For a single hard link case, go through a fast path that does not + * need to iterate the fs/subvolume tree. + */ + if (inode->vfs_inode.i_nlink < 2) + return log_new_ancestors_fast(trans, inode, parent, ctx); + + path = btrfs_alloc_path(); + if (!path) + return -ENOMEM; + + search_key.objectid = ino; + search_key.type = BTRFS_INODE_REF_KEY; + search_key.offset = 0; +again: + ret = btrfs_search_slot(NULL, root, &search_key, path, 0, 0); + if (ret < 0) + goto out; + if (ret == 0) + path->slots[0]++; + + while (true) { + struct extent_buffer *leaf = path->nodes[0]; + int slot = path->slots[0]; + struct btrfs_key found_key; + + if (slot >= btrfs_header_nritems(leaf)) { + ret = btrfs_next_leaf(root, path); + if (ret < 0) + goto out; + else if (ret > 0) + break; + continue; + } + + btrfs_item_key_to_cpu(leaf, &found_key, slot); + if (found_key.objectid != ino || + found_key.type > BTRFS_INODE_EXTREF_KEY) + break; + + /* + * Don't deal with extended references because they are rare + * cases and too complex to deal with (we would need to keep + * track of which subitem we are processing for each item in + * this loop, etc). So just return some error to fallback to + * a transaction commit. + */ + if (found_key.type == BTRFS_INODE_EXTREF_KEY) { + ret = -EMLINK; + goto out; + } + + /* + * Logging ancestors needs to do more searches on the fs/subvol + * tree, so it releases the path as needed to avoid deadlocks. + * Keep track of the last inode ref key and resume from that key + * after logging all new ancestors for the current hard link. + */ + memcpy(&search_key, &found_key, sizeof(search_key)); + + ret = log_new_ancestors(trans, root, path, ctx); + if (ret) + goto out; + btrfs_release_path(path); + goto again; + } + ret = 0; +out: + btrfs_free_path(path); + return ret; +} + /* * helper function around btrfs_log_inode to make sure newly created * parent directories also end up in the log. A minimal inode and backref @@ -5849,11 +6033,9 @@ static int btrfs_log_inode_parent(struct btrfs_trans_handle *trans, struct btrfs_root *root = inode->root; struct btrfs_fs_info *fs_info = root->fs_info; struct super_block *sb; - struct dentry *old_parent = NULL; int ret = 0; u64 last_committed = fs_info->last_trans_committed; bool log_dentries = false; - struct btrfs_inode *orig_inode = inode; sb = inode->vfs_inode.i_sb; @@ -5959,54 +6141,20 @@ static int btrfs_log_inode_parent(struct btrfs_trans_handle *trans, * and has a link count of 2. */ if (inode->last_unlink_trans > last_committed) { - ret = btrfs_log_all_parents(trans, orig_inode, ctx); + ret = btrfs_log_all_parents(trans, inode, ctx); if (ret) goto end_trans; } - /* - * If a new hard link was added to the inode in the current transaction - * and its link count is now greater than 1, we need to fallback to a - * transaction commit, otherwise we can end up not logging all its new - * parents for all the hard links. Here just from the dentry used to - * fsync, we can not visit the ancestor inodes for all the other hard - * links to figure out if any is new, so we fallback to a transaction - * commit (instead of adding a lot of complexity of scanning a btree, - * since this scenario is not a common use case). - */ - if (inode->vfs_inode.i_nlink > 1 && - inode->last_link_trans > last_committed) { - ret = -EMLINK; + ret = log_all_new_ancestors(trans, inode, parent, ctx); + if (ret) goto end_trans; - } - - while (1) { - if (!parent || d_really_is_negative(parent) || sb != parent->d_sb) - break; - - inode = BTRFS_I(d_inode(parent)); - if (root != inode->root) - break; - if (inode->generation > last_committed) { - ret = btrfs_log_inode(trans, root, inode, - LOG_INODE_EXISTS, 0, LLONG_MAX, ctx); - if (ret) - goto end_trans; - } - if (IS_ROOT(parent)) - break; - - parent = dget_parent(parent); - dput(old_parent); - old_parent = parent; - } if (log_dentries) - ret = log_new_dir_dentries(trans, root, orig_inode, ctx); + ret = log_new_dir_dentries(trans, root, inode, ctx); else ret = 0; end_trans: - dput(old_parent); if (ret < 0) { btrfs_set_log_full_commit(trans); ret = 1; |