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Subject: Re: [PATCH 00/12] block/bio, fs: convert put_page() to
 put_user_page*()
To:     Christoph Hellwig <hch@infradead.org>
CC:     <john.hubbard@gmail.com>,
        Andrew Morton <akpm@linux-foundation.org>,
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 <20190724061750.GA19397@infradead.org>
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From:   John Hubbard <jhubbard@nvidia.com>
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Date:   Tue, 6 Aug 2019 23:38:59 -0700
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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

From mboxrd@z Thu Jan  1 00:00:00 1970
From: John Hubbard <jhubbard@nvidia.com>
Subject: Re: [PATCH 00/12] block/bio, fs: convert put_page() to
	put_user_page*()
Date: Tue, 6 Aug 2019 23:38:59 -0700
Message-ID: <3ab1e69f-88c6-3e16-444d-cab78c3bf1d1@nvidia.com>
References: <20190724042518.14363-1-jhubbard@nvidia.com>
	<20190724061750.GA19397@infradead.org>
	<c35aa2bf-c830-9e57-78ca-9ce6fb6cb53b@nvidia.com>
	<20190807063448.GA6002@infradead.org>
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To: Christoph Hellwig <hch@infradead.org>
Cc: kvm@vger.kernel.org, "Michael S . Tsirkin" <mst@redhat.com>, virtualization@lists.linux-foundation.org, linux-mm@kvack.org, Christoph Hellwig <hch@lst.de>, linux-cifs@vger.kernel.org, Miklos Szeredi <miklos@szeredi.hu>, linux-rdma@vger.kernel.org, Matthew Wilcox <willy@infradead.org>, Jason Gunthorpe <jgg@ziepe.ca>, v9fs-developer@lists.sourceforge.net, Eric Van Hensbergen <ericvh@gmail.com>, john.hubbard@gmail.com, linux-block@vger.kernel.org, Alexander Viro <viro@zeniv.linux.org.uk>, ceph-devel@vger.kernel.org, Trond Myklebust <trond.myklebust@hammerspace.com>, Jens Axboe <axboe@kernel.dk>, linux-nfs@vger.kernel.org, netdev@vger.kernel.org, samba-technical@lists.samba.org, LKML <linux-kernel@vger.kernel.org>, "David S . Miller" <davem@davemloft.net>, linux-fsdevel@vger.kernel.org, Andrew Morton <akpm@linux-foundation.org>, Anna Schumaker <anna.schumaker@netapp.com>
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