+static int btrfs_rename(struct inode * old_dir, struct dentry *old_dentry,
+ struct inode * new_dir,struct dentry *new_dentry)
+{
+ struct btrfs_trans_handle *trans;
+ struct btrfs_root *root = BTRFS_I(old_dir)->root;
+ struct inode *new_inode = new_dentry->d_inode;
+ struct inode *old_inode = old_dentry->d_inode;
+ struct timespec ctime = CURRENT_TIME;
+ struct btrfs_path *path;
+ struct btrfs_dir_item *di;
+ int ret;
+
+ if (S_ISDIR(old_inode->i_mode) && new_inode &&
+ new_inode->i_size > BTRFS_EMPTY_DIR_SIZE) {
+ return -ENOTEMPTY;
+ }
+ mutex_lock(&root->fs_info->fs_mutex);
+ trans = btrfs_start_transaction(root, 1);
+ btrfs_set_trans_block_group(trans, new_dir);
+ path = btrfs_alloc_path();
+ if (!path) {
+ ret = -ENOMEM;
+ goto out_fail;
+ }
+
+ old_dentry->d_inode->i_nlink++;
+ old_dir->i_ctime = old_dir->i_mtime = ctime;
+ new_dir->i_ctime = new_dir->i_mtime = ctime;
+ old_inode->i_ctime = ctime;
+ if (S_ISDIR(old_inode->i_mode) && old_dir != new_dir) {
+ struct btrfs_key *location = &BTRFS_I(new_dir)->location;
+ u64 old_parent_oid;
+ di = btrfs_lookup_dir_item(trans, root, path, old_inode->i_ino,
+ "..", 2, -1);
+ if (IS_ERR(di)) {
+ ret = PTR_ERR(di);
+ goto out_fail;
+ }
+ if (!di) {
+ ret = -ENOENT;
+ goto out_fail;
+ }
+ old_parent_oid = btrfs_disk_key_objectid(&di->location);
+ ret = btrfs_del_item(trans, root, path);
+ if (ret) {
+ ret = -EIO;
+ goto out_fail;
+ }
+ btrfs_release_path(root, path);
+
+ di = btrfs_lookup_dir_index_item(trans, root, path,
+ old_inode->i_ino,
+ old_parent_oid,
+ "..", 2, -1);
+ if (IS_ERR(di)) {
+ ret = PTR_ERR(di);
+ goto out_fail;
+ }
+ if (!di) {
+ ret = -ENOENT;
+ goto out_fail;
+ }
+ ret = btrfs_del_item(trans, root, path);
+ if (ret) {
+ ret = -EIO;
+ goto out_fail;
+ }
+ btrfs_release_path(root, path);
+
+ ret = btrfs_insert_dir_item(trans, root, "..", 2,
+ old_inode->i_ino, location, 0);
+ if (ret)
+ goto out_fail;
+ }
+
+
+ ret = btrfs_add_link(trans, new_dentry, old_inode);
+ if (ret == -EEXIST && new_inode)
+ ret = 0;
+ else if (ret)
+ goto out_fail;
+
+ ret = btrfs_unlink_trans(trans, root, old_dir, old_dentry);
+ if (ret)
+ goto out_fail;
+
+ if (new_inode) {
+ new_inode->i_ctime = CURRENT_TIME;
+ di = btrfs_lookup_dir_index_item(trans, root, path,
+ new_dir->i_ino,
+ new_inode->i_ino,
+ new_dentry->d_name.name,
+ new_dentry->d_name.len, -1);
+ if (di && !IS_ERR(di)) {
+ btrfs_del_item(trans, root, path);
+ btrfs_release_path(root, path);
+ }
+ if (S_ISDIR(new_inode->i_mode))
+ clear_nlink(new_inode);
+ else
+ drop_nlink(new_inode);
+ btrfs_update_inode(trans, root, new_inode);
+ }
+out_fail:
+ btrfs_free_path(path);
+ btrfs_end_transaction(trans, root);
+ mutex_unlock(&root->fs_info->fs_mutex);
+ return ret;
+}
+