On Wed, Jun 13, 2018 at 07:06:41PM +0800, Ming Lei wrote: > > before bio_alloc_pages) that can be switched to something that just creates > > a > > single bvec. > > Yes, multipage bvec shouldn't break any driver or fs.
It probably isn't broken, at least I didn't see assumptions of the same number of segments. However the current poking into the bio internals as a bad idea for a couple of reasons. First because it requires touching bcache for any of these changes, second because it won't get merging of pages into a single bio segment for bіos built by bch_bio_map or bch_bio_alloc_pages, and third bcache is the last user of bio_for_each_chunk_all in your branch, which I'd like to kill off to keep the number of iterators down.
