diff options
| -rw-r--r-- | fs/btrfs/tree-log.c | 64 |
1 files changed, 60 insertions, 4 deletions
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c index 9c45431..cb5666e 100644 --- a/fs/btrfs/tree-log.c +++ b/fs/btrfs/tree-log.c @@ -1613,6 +1613,9 @@ static bool name_in_log_ref(struct btrfs_root *log_root, * not exist in the FS, it is skipped. fsyncs on directories * do not force down inodes inside that directory, just changes to the * names or unlinks in a directory. + * + * Returns < 0 on error, 0 if the name wasn't replayed (dentry points to a + * non-existing inode) and 1 if the name was replayed. */ static noinline int replay_one_name(struct btrfs_trans_handle *trans, struct btrfs_root *root, @@ -1631,6 +1634,7 @@ static noinline int replay_one_name(struct btrfs_trans_handle *trans, int exists; int ret = 0; bool update_size = (key->type == BTRFS_DIR_INDEX_KEY); + bool name_added = false; dir = read_one_inode(root, key->objectid); if (!dir) @@ -1708,6 +1712,8 @@ out: } kfree(name); iput(dir); + if (!ret && name_added) + ret = 1; return ret; insert: @@ -1723,6 +1729,8 @@ insert: name, name_len, log_type, &log_key); if (ret && ret != -ENOENT && ret != -EEXIST) goto out; + if (!ret) + name_added = true; update_size = false; ret = 0; goto out; @@ -1740,12 +1748,13 @@ static noinline int replay_one_dir_item(struct btrfs_trans_handle *trans, struct extent_buffer *eb, int slot, struct btrfs_key *key) { - int ret; + int ret = 0; u32 item_size = btrfs_item_size_nr(eb, slot); struct btrfs_dir_item *di; int name_len; unsigned long ptr; unsigned long ptr_end; + struct btrfs_path *fixup_path = NULL; ptr = btrfs_item_ptr_offset(eb, slot); ptr_end = ptr + item_size; @@ -1755,12 +1764,59 @@ static noinline int replay_one_dir_item(struct btrfs_trans_handle *trans, return -EIO; name_len = btrfs_dir_name_len(eb, di); ret = replay_one_name(trans, root, path, eb, di, key); - if (ret) - return ret; + if (ret < 0) + break; ptr = (unsigned long)(di + 1); ptr += name_len; + + /* + * If this entry refers to a non-directory (directories can not + * have a link count > 1) and it was added in the transaction + * that was not committed, make sure we fixup the link count of + * the inode it the entry points to. Otherwise something like + * the following would result in a directory pointing to an + * inode with a wrong link that does not account for this dir + * entry: + * + * mkdir testdir + * touch testdir/foo + * touch testdir/bar + * sync + * + * ln testdir/bar testdir/bar_link + * ln testdir/foo testdir/foo_link + * xfs_io -c "fsync" testdir/bar + * + * <power failure> + * + * mount fs, log replay happens + * + * File foo would remain with a link count of 1 when it has two + * entries pointing to it in the directory testdir. This would + * make it impossible to ever delete the parent directory has + * it would result in stale dentries that can never be deleted. + */ + if (ret == 1 && btrfs_dir_type(eb, di) != BTRFS_FT_DIR) { + struct btrfs_key di_key; + + if (!fixup_path) { + fixup_path = btrfs_alloc_path(); + if (!fixup_path) { + ret = -ENOMEM; + break; + } + } + + btrfs_dir_item_key_to_cpu(eb, di, &di_key); + ret = link_to_fixup_dir(trans, root, fixup_path, + di_key.objectid); + if (ret) + break; + } + ret = 0; } - return 0; + btrfs_free_path(fixup_path); + return ret; } /* |
