nfs41: Process callback's referring call list

If a CB_SEQUENCE referring call triple matches a slot table entry, the
client is still waiting for a response to the original request.  In this
case, return NFS4ERR_DELAY as the response to the callback.

Signed-off-by: Mike Sager <sager@netapp.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

1 files changed, 14 insertions, 5 deletions

diff --git a/fs/nfs/callback_proc.c b/fs/nfs/callback_proc.c
index 631b44c1439b..49c4b548b4d0 100644
--- a/fs/nfs/callback_proc.c
+++ b/fs/nfs/callback_proc.c
@@ -280,17 +280,12 @@ out:
         return status;
 }
 
-/* FIXME: referring calls should be processed */
 unsigned nfs4_callback_sequence(struct cb_sequenceargs *args,
                                 struct cb_sequenceres *res)
 {
         struct nfs_client *clp;
         int i, status;
 
-        for (i = 0; i < args->csa_nrclists; i++)
-                kfree(args->csa_rclists[i].rcl_refcalls);
-        kfree(args->csa_rclists);
-
         status = htonl(NFS4ERR_BADSESSION);
         clp = find_client_with_session(args->csa_addr, 4, &args->csa_sessionid);
         if (clp == NULL)
@@ -301,6 +296,16 @@ unsigned nfs4_callback_sequence(struct cb_sequenceargs *args,
         if (status)
                 goto out_putclient;
 
+        /*
+         * Check for pending referring calls.  If a match is found, a
+         * related callback was received before the response to the original
+         * call.
+         */
+        if (referring_call_exists(clp, args->csa_nrclists, args->csa_rclists)) {
+                status = htonl(NFS4ERR_DELAY);
+                goto out_putclient;
+        }
+
         memcpy(&res->csr_sessionid, &args->csa_sessionid,
                sizeof(res->csr_sessionid));
         res->csr_sequenceid = args->csa_sequenceid;
@@ -311,6 +316,10 @@ unsigned nfs4_callback_sequence(struct cb_sequenceargs *args,
 out_putclient:
         nfs_put_client(clp);
 out:
+        for (i = 0; i < args->csa_nrclists; i++)
+                kfree(args->csa_rclists[i].rcl_refcalls);
+        kfree(args->csa_rclists);
+
         dprintk("%s: exit with status = %d\n", __func__, ntohl(status));
         res->csr_status = status;
         return res->csr_status;