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Date:   Thu, 14 Feb 2019 12:08:40 -0800
From:   Matthew Wilcox <willy@infradead.org>
To:     Dan Williams <dan.j.williams@intel.com>
Cc:     Jerome Glisse <jglisse@redhat.com>,
        Michal Hocko <mhocko@kernel.org>,
        lsf-pc@lists.linux-foundation.org,
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        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        linux-nvdimm <linux-nvdimm@lists.01.org>
Subject: Re: [Lsf-pc] [LSF/MM TOPIC] The end of the DAX experiment
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On Thu, Feb 14, 2019 at 11:31:24AM -0800, Dan Williams wrote:
> On Thu, Feb 14, 2019 at 11:10 AM Jerome Glisse <jglisse@redhat.com> wrote:
> > I am just again working on my struct page mapping patchset as well as
> > the generic page write protection that sits on top. I hope to be able
> > to post the v2 in couple weeks. You can always look at my posting last
> > year to see more details.
> 
> Yes, I have that in mind as one of the contenders. However, it's not
> clear to me that its a suitable fit for filesystem-reflink. Others
> have floated the 'page proxy' idea, so it would be good to discuss the
> merits of the general approaches.

... and my preferred option of putting pfn entries in the page cache.
Or is that what you meant by "page proxy"?