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Date:   Mon, 16 Nov 2020 22:16:01 -0500
From:   bfields <bfields@fieldses.org>
To:     Jeff Layton <jlayton@kernel.org>
Cc:     Daire Byrne <daire@dneg.com>,
        Trond Myklebust <trondmy@hammerspace.com>,
        linux-cachefs <linux-cachefs@redhat.com>,
        linux-nfs <linux-nfs@vger.kernel.org>
Subject: Re: Adventures in NFS re-exporting
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On Mon, Nov 16, 2020 at 03:03:15PM -0500, Jeff Layton wrote:
> Another idea might be to add a new fetch_iversion export operation that
> returns a u64. Roll two generic functions -- one to handle the
> xfs/ext4/btrfs case and another for the NFS/AFS/Ceph case (where we just
> fetch it raw). When the op is a NULL pointer, treat it like the
> !IS_I_VERSION case today.

OK, a rough attempt follows, mostly untested.--b.