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Date:   Thu, 23 Sep 2021 15:32:39 -0400
From:   "J. Bruce Fields" <bfields@fieldses.org>
To:     dai.ngo@oracle.com
Cc:     chuck.lever@oracle.com, linux-nfs@vger.kernel.org,
        linux-fsdevel@vger.kernel.org
Subject: Re: [PATCH v3 2/3] nfsd: Initial implementation of NFSv4 Courteous
 Server
Message-ID: <20210923193239.GD18334@fieldses.org>
References: <20210916182212.81608-1-dai.ngo@oracle.com>
 <20210916182212.81608-3-dai.ngo@oracle.com>
 <20210923013458.GE22937@fieldses.org>
 <9e33d9b7-5947-488d-343f-80c86a27fd84@oracle.com>
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On Thu, Sep 23, 2021 at 10:09:35AM -0700, dai.ngo@oracle.com wrote:
> On 9/22/21 6:34 PM, J. Bruce Fields wrote:
> >On Thu, Sep 16, 2021 at 02:22:11PM -0400, Dai Ngo wrote:
> >>+/*
> >>+ * If the conflict happens due to a NFSv4 request then check for
> >>+ * courtesy client and set rq_conflict_client so that upper layer
> >>+ * can destroy the conflict client and retry the call.
> >>+ */
> >I think we need a different approach.
> 
> I think nfsd_check_courtesy_client is used to handle conflict with
> delegation. So instead of using rq_conflict_client to let the caller
> knows and destroy the courtesy client as the current patch does, we
> can ask the laundromat thread to do the destroy.

I can't see right now why that wouldn't work.

> In that case,
> nfs4_get_vfs_file in nfsd4_process_open2 will either return no error
> since the the laufromat destroyed the courtesy client or it gets
> get nfserr_jukebox which causes the NFS client to retry. By the time
> the retry comes the courtesy client should already be destroyed.

Make sure this works for local (non-NFS) lease breakers as well.  I
think that mainly means making sure the !O_NONBLOCK case of
__break_lease works.

--b.