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Date:   Mon, 28 Mar 2022 23:16:56 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Qu Wenruo <quwenruo.btrfs@gmx.com>
Cc:     Sweet Tea Dorminy <sweettea-kernel@dorminy.me>,
        Christoph Hellwig <hch@infradead.org>,
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Subject: Re: [PATCH RFC 2/2] btrfs: do data read repair in synchronous mode
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On Sat, Mar 26, 2022 at 08:13:33AM +0800, Qu Wenruo wrote:
> > I'm not understanding the reason why each bvec can only have one page...
> > as far as I know, a bvec could have any number of contiguous pages,
> > making it infeasible for x86_64 too, but maybe I'm missing some
> > constraint in their construction to make it one-to-one.
> 
> Btrfs doesn't utilize that multi-page bvec at all.

That is not true.  multi-page bvec are automatically created by
bio_add_page which is used by btrfs everywhere.