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Subject: Re: Adventures in NFS re-exporting
Date:   Mon, 28 Sep 2020 17:42:28 +0000
From:   Frank van der Linden <fllinden@amazon.com>
To:     Chuck Lever <chuck.lever@oracle.com>
CC:     Daire Byrne <daire@dneg.com>, Bruce Fields <bfields@fieldses.org>,
        "Linux NFS Mailing List" <linux-nfs@vger.kernel.org>,
        linux-cachefs <linux-cachefs@redhat.com>
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On Mon, Sep 28, 2020 at 12:08:09PM -0400, Chuck Lever wrote:
> 
> 
> > On Sep 28, 2020, at 11:49 AM, Frank van der Linden <fllinden@amazon.com> wrote:
> >
> > Bruce - if you want me to 'formally' submit a version of the patch, let me
> > know. Just disabling the cache for v4, which comes down to reverting a few
> > commits, is probably simpler - I'd be able to test that too.
> 
> I'd be interested in seeing that. From what I saw, the mechanics of
> unhooking the cache from NFSv4 simply involve reverting patches, but
> there appear to be some recent changes that depend on the open
> filecache that might be difficult to deal with, like
> 
> b66ae6dd0c30 ("nfsd: Pass the nfsd_file as arguments to nfsd4_clone_file_range()")

Hm, yes, I missed nf_rwsem being added to the struct.

Probably easier to keep nfsd_file, and have v4 use just straight alloc/free
functions for it that don't touch the cache at all.

- Frank