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Subject: Re: [PATCH 00/12] block/bio, fs: convert put_page() to
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To:     Christoph Hellwig <hch@infradead.org>
CC:     <john.hubbard@gmail.com>,
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From:   John Hubbard <jhubbard@nvidia.com>
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On 8/6/19 11:34 PM, Christoph Hellwig wrote:
> On Mon, Aug 05, 2019 at 03:54:35PM -0700, John Hubbard wrote:
>> On 7/23/19 11:17 PM, Christoph Hellwig wrote:
...
>>> I think we can do this in a simple and better way.  We have 5 ITER_*
>>> types.  Of those ITER_DISCARD as the name suggests never uses pages, so
>>> we can skip handling it.  ITER_PIPE is rejected =D1=96n the direct I/O =
path,
>>> which leaves us with three.
>>>
>>
>> Hi Christoph,
>>
>> Are you working on anything like this?
>=20
> I was hoping I could steer you towards it.  But if you don't want to do
> it yourself I'll add it to my ever growing todo list.
>=20

Sure, I'm up for this. The bvec-related items are the next logical part
of the gup/dma conversions to work on, and I just wanted to avoid solving t=
he
same problem if you were already in the code.


>> Or on the put_user_bvec() idea?
>=20
> I have a prototype from two month ago:
>=20
> http://git.infradead.org/users/hch/misc.git/shortlog/refs/heads/gup-bvec
>=20
> but that only survived the most basic testing, so it'll need more work,
> which I'm not sure when I'll find time for.
>=20

I'll take a peek, and probably pester you with a few questions if I get
confused. :)

thanks,
--=20
John Hubbard
NVIDIA