OK, let's reset this discussion.
On 8/12/25 12:03 PM, Olga Kornievskaia wrote:
> When v3 NLM request finds a conflicting delegation, it triggers
> a delegation recall and nfsd_open fails with EAGAIN. nfsd_open
> then translates EAGAIN into nfserr_jukebox. In nlm_fopen, instead
> of returning nlm_failed for when there is a conflicting delegation,
> drop this NLM request so that the client retries. Once delegation
> is recalled and if a local lock is claimed, a retry would lead to
> nfsd returning a nlm_lck_blocked error or a successful nlm lock.
If this patch "... solves a problem and a fix is needed" then we need a
Fixes: tag so the patch is prioritized and considered for LTS.
> Reviewed-by: Jeff Layton <jlayton@xxxxxxxxxx>
> Signed-off-by: Olga Kornievskaia <okorniev@xxxxxxxxxx>
> ---
> fs/nfsd/lockd.c | 14 ++++++++++++++
> 1 file changed, 14 insertions(+)
>
> diff --git a/fs/nfsd/lockd.c b/fs/nfsd/lockd.c
> index edc9f75dc75c..8fdc769d392e 100644
> --- a/fs/nfsd/lockd.c
> +++ b/fs/nfsd/lockd.c
> @@ -57,6 +57,20 @@ nlm_fopen(struct svc_rqst *rqstp, struct nfs_fh *f, struct file **filp,
> switch (nfserr) {
> case nfs_ok:
> return 0;
> + case nfserr_jukebox:
> + /* this error can indicate a presence of a conflicting
> + * delegation to an NLM lock request. Options are:
> + * (1) For now, drop this request and make the client
> + * retry. When delegation is returned, client's retry will
> + * complete.
> + * (2) NLM4_DENIED as per "spec" signals to the client
> + * that the lock is unavaiable now but client can retry.
> + * Linux client implementation does not. It treats
> + * NLM4_DENIED same as NLM4_FAILED and errors the request.
> + * (3) For the future, treat this as blocked lock and try
> + * to callback when the delegation is returned but might
> + * not have a proper lock request to block on.
> + */
s/unavaiable/unavailable
Since 2020, kernel coding style uses the "fallthrough;" keyword for
switch cases with no "break;".
Although, instead of "fallthrough;", you could simply remove the
nfserr_dropit case in this patch. That would remove the conflict with
Neil's patch (if it were to be postponed until after this one).
> case nfserr_dropit:
> return nlm_drop_reply;
> case nfserr_stale:
--
Chuck Lever
