On Mon, Aug 16, 2021 at 02:03:56PM +0800, Shiyang Ruan wrote: > Some operations, such as comparing a range of data in two files under > fsdax mode, requires nested iomap_begin()/iomap_end() on two files. > Thus, we introduce iomap_iter2() to accept two iteraters to operate > action on two files. We really should not need both. We should be able to be in two nested loops, just operating on the part that both cover (for which a helper might be useful).