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Date:   Thu, 4 Nov 2021 18:35:59 +0100
From:   Christoph Hellwig <hch@lst.de>
To:     "Darrick J. Wong" <djwong@kernel.org>
Cc:     Christoph Hellwig <hch@lst.de>, Eric Sandeen <sandeen@sandeen.net>,
        Dan Williams <dan.j.williams@intel.com>,
        Mike Snitzer <snitzer@redhat.com>,
        Ira Weiny <ira.weiny@intel.com>, dm-devel@redhat.com,
        linux-xfs@vger.kernel.org, nvdimm@lists.linux.dev,
        linux-s390@vger.kernel.org, linux-fsdevel@vger.kernel.org,
        linux-erofs@lists.ozlabs.org, linux-ext4@vger.kernel.org,
        virtualization@lists.linux-foundation.org
Subject: Re: futher decouple DAX from block devices
Message-ID: <20211104173559.GB31740@lst.de>
References: <20211018044054.1779424-1-hch@lst.de> <21ff4333-e567-2819-3ae0-6a2e83ec7ce6@sandeen.net> <20211104081740.GA23111@lst.de> <20211104173417.GJ2237511@magnolia>
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On Thu, Nov 04, 2021 at 10:34:17AM -0700, Darrick J. Wong wrote:
> /me wonders, are block devices going away?  Will mkfs.xfs have to learn
> how to talk to certain chardevs?  I guess jffs2 and others already do
> that kind of thing... but I suppose I can wait for the real draft to
> show up to ramble further. ;)

Right now I've mostly been looking into the kernel side.  An no, I
do not expect /dev/pmem* to go away as you'll still need it for a
not DAX aware file system and/or application (such as mkfs initially).

But yes, just pointing mkfs to the chardev should be doable with very
little work.  We can point it to a regular file after all.