Let's skip entire non-exist area to speed up truncate_hole by
using get_next_page_offset.
Signed-off-by: NWeichao Guo <guoweichao@huawei.com>
Reviewed-by: NChao Yu <yuchao0@huawei.com>
Signed-off-by: NJaegeuk Kim <jaegeuk@kernel.org>