diff options
| -rw-r--r-- | fs/btrfs/tree-log.c | 72 |
1 files changed, 62 insertions, 10 deletions
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c index 5a91c74a721b..8202761306c9 100644 --- a/fs/btrfs/tree-log.c +++ b/fs/btrfs/tree-log.c @@ -5644,8 +5644,46 @@ static void free_conflicting_inodes(struct btrfs_log_ctx *ctx) } } +static int conflicting_inode_is_dir(struct btrfs_root *root, u64 ino, + struct btrfs_path *path) +{ + struct btrfs_key key; + int ret; + + key.objectid = ino; + key.type = BTRFS_INODE_ITEM_KEY; + key.offset = 0; + + path->search_commit_root = 1; + path->skip_locking = 1; + + ret = btrfs_search_slot(NULL, root, &key, path, 0, 0); + if (WARN_ON_ONCE(ret > 0)) { + /* + * We have previously found the inode through the commit root + * so this should not happen. If it does, just error out and + * fallback to a transaction commit. + */ + ret = -ENOENT; + } else if (ret == 0) { + struct btrfs_inode_item *item; + + item = btrfs_item_ptr(path->nodes[0], path->slots[0], + struct btrfs_inode_item); + if (S_ISDIR(btrfs_inode_mode(path->nodes[0], item))) + ret = 1; + } + + btrfs_release_path(path); + path->search_commit_root = 0; + path->skip_locking = 0; + + return ret; +} + static int add_conflicting_inode(struct btrfs_trans_handle *trans, struct btrfs_root *root, + struct btrfs_path *path, u64 ino, u64 parent, struct btrfs_log_ctx *ctx) { @@ -5665,15 +5703,23 @@ static int add_conflicting_inode(struct btrfs_trans_handle *trans, inode = btrfs_iget(root->fs_info->sb, ino, root); /* * If the other inode that had a conflicting dir entry was deleted in - * the current transaction, we need to log its parent directory. - * We can't simply ignore it and let the current inode's reference cause - * an unlink of the conflicting inode when replaying the log - because - * the conflicting inode may be a deleted subvolume/snapshot or it may - * be a directory that had subvolumes/snapshots inside it (or had one - * or more subdirectories with subvolumes/snapshots, etc). If that's the - * case, then when logging the parent directory we will fallback to a - * transaction commit because the parent directory will have a - * last_unlink_trans that matches the current transaction. + * the current transaction then we either: + * + * 1) Log the parent directory (later after adding it to the list) if + * the inode is a directory. This is because it may be a deleted + * subvolume/snapshot or it may be a regular directory that had + * deleted subvolumes/snapshots (or subdirectories that had them), + * and at the moment we can't deal with dropping subvolumes/snapshots + * during log replay. So we just log the parent, which will result in + * a fallback to a transaction commit if we are dealing with those + * cases (last_unlink_trans will match the current transaction); + * + * 2) Do nothing if it's not a directory. During log replay we simply + * unlink the conflicting dentry from the parent directory and then + * add the dentry for our inode. Like this we can avoid logging the + * parent directory (and maybe fallback to a transaction commit in + * case it has a last_unlink_trans == trans->transid, due to moving + * some inode from it to some other directory). */ if (IS_ERR(inode)) { int ret = PTR_ERR(inode); @@ -5681,6 +5727,12 @@ static int add_conflicting_inode(struct btrfs_trans_handle *trans, if (ret != -ENOENT) return ret; + ret = conflicting_inode_is_dir(root, ino, path); + /* Not a directory or we got an error. */ + if (ret <= 0) + return ret; + + /* Conflicting inode is a directory, so we'll log its parent. */ ino_elem = kmalloc(sizeof(*ino_elem), GFP_NOFS); if (!ino_elem) return -ENOMEM; @@ -5919,7 +5971,7 @@ again: ins_nr = 0; btrfs_release_path(path); - ret = add_conflicting_inode(trans, root, + ret = add_conflicting_inode(trans, root, path, other_ino, other_parent, ctx); if (ret) |