diff options
Diffstat (limited to 'root-tree.c')
| -rw-r--r-- | root-tree.c | 37 |
1 files changed, 37 insertions, 0 deletions
diff --git a/root-tree.c b/root-tree.c index ef2190fc..ba380bd4 100644 --- a/root-tree.c +++ b/root-tree.c @@ -69,6 +69,7 @@ int btrfs_update_root(struct btrfs_trans_handle *trans, struct btrfs_root int ret; int slot; unsigned long ptr; + u32 old_len; path = btrfs_alloc_path(); BUG_ON(!path); @@ -79,6 +80,42 @@ int btrfs_update_root(struct btrfs_trans_handle *trans, struct btrfs_root l = path->nodes[0]; slot = path->slots[0]; ptr = btrfs_item_ptr_offset(l, slot); + old_len = btrfs_item_size_nr(l, slot); + + /* + * If this is the first time we update the root item which originated + * from an older kernel, we need to enlarge the item size to make room + * for the added fields. + */ + if (old_len < sizeof(*item)) { + btrfs_release_path(root, path); + ret = btrfs_search_slot(trans, root, key, path, + -1, 1); + if (ret < 0) { + goto out; + } + + ret = btrfs_del_item(trans, root, path); + if (ret < 0) { + goto out; + } + btrfs_release_path(root, path); + ret = btrfs_insert_empty_item(trans, root, path, + key, sizeof(*item)); + if (ret < 0) { + goto out; + } + l = path->nodes[0]; + slot = path->slots[0]; + ptr = btrfs_item_ptr_offset(l, slot); + } + + /* + * Update generation_v2 so at the next mount we know the new root + * fields are valid. + */ + btrfs_set_root_generation_v2(item, btrfs_root_generation(item)); + write_extent_buffer(l, item, ptr, sizeof(*item)); btrfs_mark_buffer_dirty(path->nodes[0]); out: |