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Date:   Thu, 29 Aug 2019 02:32:38 -0700
From:   Christoph Hellwig <hch@infradead.org>
To:     Dan Williams <dan.j.williams@intel.com>
Cc:     Dave Chinner <david@fromorbit.com>,
        Vivek Goyal <vgoyal@redhat.com>,
        Christoph Hellwig <hch@infradead.org>,
        Miklos Szeredi <miklos@szeredi.hu>,
        linux-nvdimm <linux-nvdimm@lists.01.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        "Dr. David Alan Gilbert" <dgilbert@redhat.com>,
        virtio-fs@redhat.com, Stefan Hajnoczi <stefanha@redhat.com>,
        linux-fsdevel <linux-fsdevel@vger.kernel.org>
Subject: Re: [PATCH 01/19] dax: remove block device dependencies
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On Wed, Aug 28, 2019 at 05:04:11PM -0700, Dan Williams wrote:
> Agree. In retrospect it was my laziness in the dax-device
> implementation to expect the block-device to be available.
> 
> It looks like fs_dax_get_by_bdev() is an intercept point where a
> dax_device could be dynamically created to represent the subset range
> indicated by the block-device partition. That would open up more
> cleanup opportunities.

That seems like a decent short-term plan.  But in the long I'd just let
dax call into the partition table parser directly, as we might want to
support partitions without first having to create a block device on top
of the dax device.  Same for the badblocks handling story.