diff options
Diffstat (limited to 'fs/btrfs/ctree.c')
| -rw-r--r-- | fs/btrfs/ctree.c | 69 |
1 files changed, 48 insertions, 21 deletions
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c index 362879da4f0d..0abed1a0caa7 100644 --- a/fs/btrfs/ctree.c +++ b/fs/btrfs/ctree.c @@ -1866,7 +1866,6 @@ static void root_sub_used(struct btrfs_root *root, u32 size) /* given a node and slot number, this reads the blocks it points to. The * extent buffer is returned with a reference taken (but unlocked). - * NULL is returned on error. */ static noinline struct extent_buffer *read_node_slot(struct btrfs_root *root, struct extent_buffer *parent, int slot) @@ -1874,19 +1873,16 @@ static noinline struct extent_buffer *read_node_slot(struct btrfs_root *root, int level = btrfs_header_level(parent); struct extent_buffer *eb; - if (slot < 0) - return NULL; - if (slot >= btrfs_header_nritems(parent)) - return NULL; + if (slot < 0 || slot >= btrfs_header_nritems(parent)) + return ERR_PTR(-ENOENT); BUG_ON(level == 0); eb = read_tree_block(root, btrfs_node_blockptr(parent, slot), btrfs_node_ptr_generation(parent, slot)); - if (IS_ERR(eb) || !extent_buffer_uptodate(eb)) { - if (!IS_ERR(eb)) - free_extent_buffer(eb); - eb = NULL; + if (!IS_ERR(eb) && !extent_buffer_uptodate(eb)) { + free_extent_buffer(eb); + eb = ERR_PTR(-EIO); } return eb; @@ -1939,8 +1935,8 @@ static noinline int balance_level(struct btrfs_trans_handle *trans, /* promote the child to a root */ child = read_node_slot(root, mid, 0); - if (!child) { - ret = -EROFS; + if (IS_ERR(child)) { + ret = PTR_ERR(child); btrfs_handle_fs_error(root->fs_info, ret, NULL); goto enospc; } @@ -1978,6 +1974,9 @@ static noinline int balance_level(struct btrfs_trans_handle *trans, return 0; left = read_node_slot(root, parent, pslot - 1); + if (IS_ERR(left)) + left = NULL; + if (left) { btrfs_tree_lock(left); btrfs_set_lock_blocking(left); @@ -1988,7 +1987,11 @@ static noinline int balance_level(struct btrfs_trans_handle *trans, goto enospc; } } + right = read_node_slot(root, parent, pslot + 1); + if (IS_ERR(right)) + right = NULL; + if (right) { btrfs_tree_lock(right); btrfs_set_lock_blocking(right); @@ -2143,6 +2146,8 @@ static noinline int push_nodes_for_insert(struct btrfs_trans_handle *trans, return 1; left = read_node_slot(root, parent, pslot - 1); + if (IS_ERR(left)) + left = NULL; /* first, try to make some room in the middle buffer */ if (left) { @@ -2193,6 +2198,8 @@ static noinline int push_nodes_for_insert(struct btrfs_trans_handle *trans, free_extent_buffer(left); } right = read_node_slot(root, parent, pslot + 1); + if (IS_ERR(right)) + right = NULL; /* * then try to empty the right most buffer into the middle @@ -3781,7 +3788,11 @@ static int push_leaf_right(struct btrfs_trans_handle *trans, struct btrfs_root btrfs_assert_tree_locked(path->nodes[1]); right = read_node_slot(root, upper, slot + 1); - if (right == NULL) + /* + * slot + 1 is not valid or we fail to read the right node, + * no big deal, just return. + */ + if (IS_ERR(right)) return 1; btrfs_tree_lock(right); @@ -4011,7 +4022,11 @@ static int push_leaf_left(struct btrfs_trans_handle *trans, struct btrfs_root btrfs_assert_tree_locked(path->nodes[1]); left = read_node_slot(root, path->nodes[1], slot - 1); - if (left == NULL) + /* + * slot - 1 is not valid or we fail to read the left node, + * no big deal, just return. + */ + if (IS_ERR(left)) return 1; btrfs_tree_lock(left); @@ -5218,7 +5233,10 @@ find_next_key: } btrfs_set_path_blocking(path); cur = read_node_slot(root, cur, slot); - BUG_ON(!cur); /* -ENOMEM */ + if (IS_ERR(cur)) { + ret = PTR_ERR(cur); + goto out; + } btrfs_tree_read_lock(cur); @@ -5237,15 +5255,21 @@ out: return ret; } -static void tree_move_down(struct btrfs_root *root, +static int tree_move_down(struct btrfs_root *root, struct btrfs_path *path, int *level, int root_level) { + struct extent_buffer *eb; + BUG_ON(*level == 0); - path->nodes[*level - 1] = read_node_slot(root, path->nodes[*level], - path->slots[*level]); + eb = read_node_slot(root, path->nodes[*level], path->slots[*level]); + if (IS_ERR(eb)) + return PTR_ERR(eb); + + path->nodes[*level - 1] = eb; path->slots[*level - 1] = 0; (*level)--; + return 0; } static int tree_move_next_or_upnext(struct btrfs_root *root, @@ -5290,8 +5314,7 @@ static int tree_advance(struct btrfs_root *root, if (*level == 0 || !allow_down) { ret = tree_move_next_or_upnext(root, path, level, root_level); } else { - tree_move_down(root, path, level, root_level); - ret = 0; + ret = tree_move_down(root, path, level, root_level); } if (ret >= 0) { if (*level == 0) @@ -5465,8 +5488,10 @@ int btrfs_compare_trees(struct btrfs_root *left_root, left_root_level, advance_left != ADVANCE_ONLY_NEXT, &left_key); - if (ret < 0) + if (ret == -1) left_end_reached = ADVANCE; + else if (ret < 0) + goto out; advance_left = 0; } if (advance_right && !right_end_reached) { @@ -5474,8 +5499,10 @@ int btrfs_compare_trees(struct btrfs_root *left_root, right_root_level, advance_right != ADVANCE_ONLY_NEXT, &right_key); - if (ret < 0) + if (ret == -1) right_end_reached = ADVANCE; + else if (ret < 0) + goto out; advance_right = 0; } |