Re: [PATCH V11 17/19] block: document usage of bio iterator helpers

[Christoph Hellwig]

On Wed, Nov 21, 2018 at 09:45:25AM +0200, Nikolay Borisov wrote:
> > +	bio_for_each_segment_all()
> > +	bio_first_bvec_all()
> > +	bio_first_page_all()
> > +	bio_last_bvec_all()
> > +
> > +* The following helpers iterate over single-page bvecs. The passed 'struct
> > +bio_vec' will contain a single-page IO vector during the iteration
> > +
> > +	bio_for_each_segment()
> > +	bio_for_each_segment_all()
> > +
> > +* The following helpers iterate over single-page bvecs. The passed 'struct
> > +bio_vec' will contain a single-page IO vector during the iteration
> > +
> > +	bio_for_each_bvec()
> 
> Just put this helper right below the above 2, no need to repeat the
> explanation. Also I'd suggest introducing another catch-all sentence
> "All other helpers are assumed to iterate multipage bio vecs" and
> perhaps give an example with 1-2 helpers.

Well, I think the second explanation is wrong - bio_for_each_bvec
iterates over the whole bvecs, not just single page.