On Mon, May 28, 2018 at 10:30:43AM +0800, Ming Lei wrote: > I hate the conversion too, but looks it can't be avoided since > bio_for_each_segment_all() has to be changed. I guess you mean what is currently bio_for_each_page_all in your tree which now takes a bvec_iter_all agument? We could just try to hide the bia variable initially under an unlike to be used name, and then slowly move to the proper bio_for_each_page_all API unhiding it with the rename. But I think your current bio_for_each_segment_all should just go away. All three users really should be using better abstractions.