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Date:   Thu, 15 Aug 2019 11:51:02 -0300
From:   Jason Gunthorpe <jgg@ziepe.ca>
To:     Jan Kara <jack@suse.cz>
Cc:     John Hubbard <jhubbard@nvidia.com>,
        Ira Weiny <ira.weiny@intel.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Christoph Hellwig <hch@infradead.org>,
        Dan Williams <dan.j.williams@intel.com>,
        Dave Chinner <david@fromorbit.com>,
        =?utf-8?B?SsOpcsO0bWU=?= Glisse <jglisse@redhat.com>,
        LKML <linux-kernel@vger.kernel.org>, linux-mm@kvack.org,
        linux-fsdevel@vger.kernel.org, linux-rdma@vger.kernel.org
Subject: Re: [RFC PATCH 2/2] mm/gup: introduce vaddr_pin_pages_remote()
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On Thu, Aug 15, 2019 at 03:35:10PM +0200, Jan Kara wrote:

> > 3) ODP case - GUP references to pages serving as DMA buffers, MMU notifiers
> >    used to synchronize with page_mkclean() and munmap() => normal page
> >    references are fine.
> 
> I want to add that I'd like to convert users in cases 1) and 2) from using
> GUP to using differently named function. Users in case 3) can stay as they
> are for now although ultimately I'd like to denote such use cases in a
> special way as well...

3) users also want a special function and path, right now it is called
hmm_range_fault() but perhaps it would be good to harmonize it more
with the GUP infrastructure?

I'm not quite sure what the best plan for that is yet.

Jason