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Date: Mon, 4 May 2009 07:08:41 -0400
From: Christoph Hellwig <hch@infradead.org>
To: Johannes Weiner <hannes@cmpxchg.org>
Cc: Andrew Morton <akpm@linux-foundation.org>,
       Magnus Damm <magnus.damm@gmail.com>, linux-media@vger.kernel.org,
       Hans Verkuil <hverkuil@xs4all.nl>, Paul Mundt <lethal@linux-sh.org>,
       linux-mm@kvack.org, linux-kernel@vger.kernel.org
Subject: Re: [patch 3/3] mm: introduce follow_pfn()
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References: <20090501181449.GA8912@cmpxchg.org> <1241430874-12667-3-git-send-email-hannes@cmpxchg.org>
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On Mon, May 04, 2009 at 11:54:34AM +0200, Johannes Weiner wrote:
> Analoguous to follow_phys(), add a helper that looks up the PFN
> instead.  It also only allows IO mappings or PFN mappings.

A kerneldoc describing what it does and the limitations would be
extremly helpful.