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Date: Fri, 23 Nov 2018 10:19:34 +0800
From: Ming Lei <ming.lei@redhat.com>
To: Christoph Hellwig <hch@lst.de>
Cc: Jens Axboe <axboe@kernel.dk>, linux-block@vger.kernel.org,
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Subject: Re: [PATCH V11 12/19] block: allow bio_for_each_segment_all() to
 iterate over multi-page bvec
Message-ID: <20181123021933.GB20110@ming.t460p>
References: <20181121032327.8434-1-ming.lei@redhat.com>
 <20181121032327.8434-13-ming.lei@redhat.com>
 <20181122110315.GA30369@lst.de>
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On Thu, Nov 22, 2018 at 12:03:15PM +0100, Christoph Hellwig wrote:
> > +/* used for chunk_for_each_segment */
> > +static inline void bvec_next_segment(const struct bio_vec *bvec,
> > +				     struct bvec_iter_all *iter_all)
> 
> FYI, chunk_for_each_segment doesn't exist anymore, this is
> bvec_for_each_segment now.  Not sure the comment helps much, though.

OK, will remove the comment.

> 
> > +{
> > +	struct bio_vec *bv = &iter_all->bv;
> > +
> > +	if (bv->bv_page) {
> > +		bv->bv_page += 1;
> 
> I think this needs to use nth_page() given that with discontigmem
> page structures might not be allocated contigously.

Good catch!

Thanks,
Ming