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Subject: Re: [PATCH v4 0/8] block: prepare for multipage bvecs
To: Ming Lei <ming.lei@canonical.com>, Jens Axboe <axboe@fb.com>,
        linux-kernel@vger.kernel.org
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From: Jens Axboe <axboe@kernel.dk>
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Date: Thu, 14 Apr 2016 08:11:03 -0600
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On 04/14/2016 05:46 AM, Ming Lei wrote:
> Hi,
>
> Interests[1] have been shown in multipage bvecs, so this patchset
> try to prepare for the support and do two things:
>
> 1) the 1st 4 patches use bvec iterator to implement iterate_bvec(),
> then we can drop the non-standard way for iterating bvec, which
> can be thought as a good cleanup for lib/iov_iter.c
>
> 2) remove BIO_MAX_SECTORS & BIO_MAX_SIZE, and now there is only
> one user for each. Once multipage bvecs is introduced, one bio
> may hold lots of sectors, and we should always use sort of BIO_MAX_VECS
> which should be introduced in future and is similiar with current
> BIO_MAX_PAGES.
>
> xfstests(-a auto) have been run over ext4/xfs and no regression found
> by this patchset.

We've had too many disasters in the block layer the last few series, I'm 
making the 4.7 round a nice and small one. I don't mind taking prep 
patches for the multipage bvecs, if they are simple and clean, but 
that's about the extent of it.

Just a heads up.

-- 
Jens Axboe