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Date:   Thu, 4 Nov 2021 09:17:40 +0100
From:   Christoph Hellwig <hch@lst.de>
To:     Eric Sandeen <sandeen@sandeen.net>
Cc:     Christoph Hellwig <hch@lst.de>,
        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: <20211104081740.GA23111@lst.de>
References: <20211018044054.1779424-1-hch@lst.de> <21ff4333-e567-2819-3ae0-6a2e83ec7ce6@sandeen.net>
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On Wed, Nov 03, 2021 at 12:59:31PM -0500, Eric Sandeen wrote:
> Christoph, can I ask what the end game looks like, here? If dax is completely
> decoupled from block devices, are there user-visible changes?

Yes.

> If I want to
> run fs-dax on a pmem device - what do I point mkfs at, if not a block device?

The rough plan is to use the device dax character devices.  I'll hopefully
have a draft version in the next days.