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Date:   Fri, 9 Sep 2022 19:11:41 +0100
From:   Matthew Wilcox <willy@infradead.org>
To:     Dan Williams <dan.j.williams@intel.com>
Cc:     Jason Gunthorpe <jgg@nvidia.com>, akpm@linux-foundation.org,
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        John Hubbard <jhubbard@nvidia.com>, linux-mm@kvack.org,
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Subject: Re: [PATCH 00/13] Fix the DAX-gup mistake
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On Thu, Sep 08, 2022 at 12:27:06PM -0700, Dan Williams wrote:
> This thread is mainly about DAX slowly reinventing _mapcount that gets
> managed in all the right places for a normal_page. Longer term I think
> we either need to get back to the page-less DAX experiment and find a
> way to unwind some of this page usage creep, or cut over to finally
> making DAX-pages be normal pages and delete most of the special case
> handling in fs/dax.c. I am open to discussing the former, but I think
> the latter is more likely.

I'm still very much in favour of the former.  I've started on replacing
scatterlist with phyr, but haven't got very far yet.