On May 10, 2018, at 12:40 AM, Christoph Hellwig wrote: > > On Wed, May 09, 2018 at 08:12:43AM -0700, Matthew Wilcox wrote: >> (page, len, off) is a bit weird to me. Usually we do (page, off, len). > > That's what I'd usually do, too. But this odd convention is what > bio_add_page uses, so I decided to stick to that instead of having two > different conventions in one family of functions. Would it make sense to change the bio_add_page() and bio_add_pc_page() to use the more common convention instead of continuing the spread of this non-standard calling convention? This is doubly problematic since "off" and "len" are both unsigned int values so it is easy to get them mixed up, and just reordering the bio_add_page() arguments would not generate any errors. One option would be to rename this function bio_page_add() so there are build errors or first add bio_page_add() and mark bio_add_page() deprecated and allow some short time for transition? There are about 50 uses under drivers/ and 50 uses under fs/. Cheers, Andreas