+ if (destoff > inode->i_size) {
+ ret = btrfs_cont_expand(inode, inode->i_size, destoff);
+ if (ret)
+ goto out_unlock;
+ }
+
+ /* truncate page cache pages from target inode range */
+ truncate_inode_pages_range(&inode->i_data, destoff,
+ PAGE_CACHE_ALIGN(destoff + len) - 1);
+