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Date: Thu, 7 May 2015 08:58:41 -0700
Message-ID: <CA+55aFyK==+bMHMdfaP4EHjUNseoTWu1-pp2M2WyLVN73ig+_g@mail.gmail.com>
Subject: Re: [PATCH v2 00/10] evacuate struct page from the block layer,
 introduce __pfn_t
From: Linus Torvalds <torvalds@linux-foundation.org>
To: Dan Williams <dan.j.williams@intel.com>
Cc: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
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On Thu, May 7, 2015 at 8:40 AM, Dan Williams <dan.j.williams@intel.com> wrote:
>
> blkdev_get(FMODE_EXCL) is the protection in this case.

Ugh. That looks like a horrible nasty big hammer that will bite us
badly some day. Since you'd have to hold it for the whole IO. But I
guess it at least works.

Anyway, I did want to say that while I may not be convinced about the
approach, I think the patches themselves don't look horrible. I
actually like your "__pfn_t". So while I (very obviously) have some
doubts about this approach, it may be that the most convincing
argument is just in the code.

                            Linus
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