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Date: Mon, 19 Dec 2016 14:11:49 -0700
From: Ross Zwisler <ross.zwisler@linux.intel.com>
To: Nicholas Piggin <npiggin@gmail.com>,
        Dave Chinner <david@fromorbit.com>, Jan Kara <jack@suse.cz>,
        Jeff Moyer <jmoyer@redhat.com>,
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Cc: Dave Chinner <david@fromorbit.com>, Yumei Huang <yuhuang@redhat.com>,
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        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
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        Andrew Morton <akpm@linux-foundation.org>
Subject: Re: DAX mapping detection (was: Re: [PATCH] Fix region lost in
 /proc/self/smaps)
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References: <20160912213435.GD30497@dastard>
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 <20160914073902.GQ22388@dastard>
 <20160914201936.08315277@roar.ozlabs.ibm.com>
 <20160915023133.GR22388@dastard>
 <20160915134945.0aaa4f5a@roar.ozlabs.ibm.com>
 <20160915103210.GT22388@dastard>
 <20160915214222.505f4888@roar.ozlabs.ibm.com>
 <20160915223350.GU22388@dastard>
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On Fri, Sep 16, 2016 at 03:54:05PM +1000, Nicholas Piggin wrote:
<>
> Definitely the first step would be your simple preallocated per
> inode approach until it is shown to be insufficient.

Reviving this thread a few months later...

Dave, we're interested in taking a serious look at what it would take to get
PMEM_IMMUTABLE working.  Do you still hold the opinion that this is (or could
become, with some amount of work) a workable solution?

We're happy to do the grunt work for this feature, but we will probably need
guidance from someone with more XFS experience.  With you out on extended leave
the first half of 2017, who would be the best person to ask for this guidance?
Darrick?

Thanks,
- Ross