nfsd: don't use the deferral service, return NFS4ERR_DELAY

On an NFSv4.1 server cache miss that causes an upcall, NFS4ERR_DELAY will be
returned. It is up to the NFSv4.1 client to resend only the operations that
have not been processed.

Initialize rq_usedeferral to 1 in svc_process(). It sill be turned off in
nfsd4_proc_compound() only when NFSv4.1 Sessions are used.

Note: this isn't an adequate solution on its own. It's acceptable as a way
to get some minimal 4.1 up and working, but we're going to have to find a
way to avoid returning DELAY in all common cases before 4.1 can really be
considered ready.

Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[nfsd41: reverse rq_nodeferral negative logic]
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
[sunrpc: initialize rq_usedeferral]
Signed-off-by: Andy Adamson <andros@netapp.com>
Signed-off-by: Benny Halevy <bhalevy@panasas.com>
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

2 files changed, 3 insertions, 1 deletions

diff --git a/net/sunrpc/svc.c b/net/sunrpc/svc.c
index fff09a2d8960..45984cbe1bfa 100644
--- a/net/sunrpc/svc.c
+++ b/net/sunrpc/svc.c
@@ -1023,6 +1023,8 @@ svc_process(struct svc_rqst *rqstp)
         rqstp->rq_res.tail[0].iov_len = 0;
         /* Will be turned off only in gss privacy case: */
         rqstp->rq_splice_ok = 1;
+        /* Will be turned off only when NFSv4 Sessions are used */
+        rqstp->rq_usedeferral = 1;
 
         /* Setup reply header */
         rqstp->rq_xprt->xpt_ops->xpo_prep_reply_hdr(rqstp);
diff --git a/net/sunrpc/svc_xprt.c b/net/sunrpc/svc_xprt.c
index 1e66f2491460..600d0918e3ae 100644
--- a/net/sunrpc/svc_xprt.c
+++ b/net/sunrpc/svc_xprt.c
@@ -974,7 +974,7 @@ static struct cache_deferred_req *svc_defer(struct cache_req *req)
         struct svc_rqst *rqstp = container_of(req, struct svc_rqst, rq_chandle);
         struct svc_deferred_req *dr;
 
-        if (rqstp->rq_arg.page_len)
+        if (rqstp->rq_arg.page_len || !rqstp->rq_usedeferral)
                 return NULL; /* if more than a page, give up FIXME */
         if (rqstp->rq_deferred) {
                 dr = rqstp->rq_deferred;