diff options
Diffstat (limited to 'ctree.c')
| -rw-r--r-- | ctree.c | 53 |
1 files changed, 52 insertions, 1 deletions
@@ -1147,7 +1147,6 @@ int btrfs_insert_empty_item(struct btrfs_trans_handle *trans, struct btrfs_root BUG(); ret = btrfs_search_slot(trans, root, cpu_key, path, data_size, 1); if (ret == 0) { - btrfs_release_path(root, path); return -EEXIST; } if (ret < 0) @@ -1369,6 +1368,58 @@ int btrfs_del_item(struct btrfs_trans_handle *trans, struct btrfs_root *root, return ret; } +int btrfs_extend_item(struct btrfs_trans_handle *trans, struct btrfs_root + *root, struct btrfs_path *path, u32 data_size) +{ + int ret = 0; + int slot; + int slot_orig; + struct btrfs_leaf *leaf; + struct btrfs_buffer *leaf_buf; + u32 nritems; + unsigned int data_end; + unsigned int old_data; + unsigned int old_size; + int i; + + slot_orig = path->slots[0]; + leaf_buf = path->nodes[0]; + leaf = &leaf_buf->leaf; + + nritems = btrfs_header_nritems(&leaf->header); + data_end = leaf_data_end(root, leaf); + + if (btrfs_leaf_free_space(root, leaf) < data_size) + BUG(); + slot = path->slots[0]; + old_data = btrfs_item_end(leaf->items + slot); + + BUG_ON(slot < 0); + BUG_ON(slot >= nritems); + + /* + * item0..itemN ... dataN.offset..dataN.size .. data0.size + */ + /* first correct the data pointers */ + for (i = slot; i < nritems; i++) { + u32 ioff = btrfs_item_offset(leaf->items + i); + btrfs_set_item_offset(leaf->items + i, + ioff - data_size); + } + /* shift the data */ + memmove(btrfs_leaf_data(leaf) + data_end - data_size, + btrfs_leaf_data(leaf) + data_end, old_data - data_end); + data_end = old_data; + old_size = btrfs_item_size(leaf->items + slot); + btrfs_set_item_size(leaf->items + slot, old_size + data_size); + + ret = 0; + if (btrfs_leaf_free_space(root, leaf) < 0) + BUG(); + check_leaf(root, path, 0); + return ret; +} + /* * walk up the tree as far as required to find the next leaf. * returns 0 if it found something or 1 if there are no greater leaves. |