ext4_ext_try_to_merge_right
merge_done = ext4_ext_try_to_merge_right(inode, path, ex - 1);
(void) ext4_ext_try_to_merge_right(inode, path, ex);
ext4_ext_try_to_merge_right(inode,
ext4_ext_try_to_merge_right(inode, path,