NFSv4: The NFSv4.0 client must send RENEW calls if it holds a delegation

RFC3530 states that if the client holds a delegation, then it is obliged
to continue to send RENEW calls once every lease period in order to allow
the server to return NFS4ERR_CB_PATH_DOWN if the callback path is
unreachable.

This is not required for NFSv4.1, since the server can at any time set
the SEQ4_STATUS_CB_PATH_DOWN_SESSION in any SEQUENCE operation.

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

1 files changed, 9 insertions, 3 deletions

diff --git a/fs/nfs/nfs4renewd.c b/fs/nfs/nfs4renewd.c
index df8e7f3ca56d..dc484c0eae7f 100644
--- a/fs/nfs/nfs4renewd.c
+++ b/fs/nfs/nfs4renewd.c
@@ -60,6 +60,7 @@ nfs4_renew_state(struct work_struct *work)
 	struct rpc_cred *cred;
 	long lease;
 	unsigned long last, now;
+	unsigned renew_flags = 0;
 
 	ops = clp->cl_mvops->state_renewal_ops;
 	dprintk("%s: start\n", __func__);
@@ -72,18 +73,23 @@ nfs4_renew_state(struct work_struct *work)
 	last = clp->cl_last_renewal;
 	now = jiffies;
 	/* Are we close to a lease timeout? */
-	if (time_after(now, last + lease/3)) {
+	if (time_after(now, last + lease/3))
+		renew_flags |= NFS4_RENEW_TIMEOUT;
+	if (nfs_delegations_present(clp))
+		renew_flags |= NFS4_RENEW_DELEGATION_CB;
+
+	if (renew_flags != 0) {
 		cred = ops->get_state_renewal_cred_locked(clp);
 		spin_unlock(&clp->cl_lock);
 		if (cred == NULL) {
-			if (!nfs_delegations_present(clp)) {
+			if (!(renew_flags & NFS4_RENEW_DELEGATION_CB)) {
 				set_bit(NFS4CLNT_LEASE_EXPIRED, &clp->cl_state);
 				goto out;
 			}
 			nfs_expire_all_delegations(clp);
 		} else {
 			/* Queue an asynchronous RENEW. */
-			ops->sched_state_renewal(clp, cred);
+			ops->sched_state_renewal(clp, cred, renew_flags);
 			put_rpccred(cred);
 			goto out_exp;
 		}