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Date:   Tue, 17 Nov 2020 10:26:36 -0500
To:     Jeff Layton <jlayton@kernel.org>
Cc:     "J. Bruce Fields" <bfields@redhat.com>,
        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: [PATCH 2/4] nfsd: pre/post attr is using wrong change attribute
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From:   bfields@fieldses.org (J. Bruce Fields)
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On Tue, Nov 17, 2020 at 07:34:49AM -0500, Jeff Layton wrote:
> I don't think I described what I was thinking well. Let me try again...
> 
> There should be no need to change the code in iversion.h -- I think we
> can do this in a way that's confined to just nfsd/export code.
> 
> What I would suggest is to have nfsd4_change_attribute call the
> fetch_iversion op if it exists, instead of checking IS_I_VERSION and
> doing the stuff in that block. If fetch_iversion is NULL, then just use
> the ctime.
> 
> Then, you just need to make sure that the filesystems' export_ops have
> an appropriate fetch_iversion vector. xfs, ext4 and btrfs can just call
> inode_query_iversion, and NFS and Ceph can call inode_peek_iversion_raw.
> The rest of the filesystems can leave fetch_iversion as NULL (since we
> don't want to use it on them).

Thanks for your patience, that makes sense, I'll try it.

--b.