On Sun, Feb 26, 2017 at 2:22 AM, Christoph Hellwig <hch@xxxxxxxxxxxxx> wrote: >> +static inline unsigned bio_segments_all(struct bio *bio) >> +{ >> + WARN_ON_ONCE(bio_flagged(bio, BIO_CLONED)); >> + >> + return bio->bi_vcnt; >> +} > > I don't think this helpers really adds any benefit. IMO the first benefit is that misusing of .bi_vcnt can be warned, and another one is that we have to introduce this helper if multipage bvec is supported. Thanks, Ming Lei