NFSv4: return all delegations we hold if the server issues a

   NFS4ERR_CB_PATH_DOWN error.

fs/nfs/delegation.c

@@ -193,6 +193,30 @@ void nfs_return_all_delegations(struct super_block *sb)
 	spin_unlock(&clp->cl_lock);
 }
 
+/*
+ * Return all delegations following an NFS4ERR_CB_PATH_DOWN error.
+ */
+void nfs_handle_cb_pathdown(struct nfs4_client *clp)
+{
+	struct nfs_delegation *delegation;
+	struct inode *inode;
+
+	if (clp == NULL)
+		return;
+restart:
+	spin_lock(&clp->cl_lock);
+	list_for_each_entry(delegation, &clp->cl_delegations, super_list) {
+		inode = igrab(delegation->inode);
+		if (inode == NULL)
+			continue;
+		spin_unlock(&clp->cl_lock);
+		nfs_inode_return_delegation(inode);
+		iput(inode);
+		goto restart;
+	}
+	spin_unlock(&clp->cl_lock);
+}
+
 struct recall_threadargs {
 	struct inode *inode;
 	struct nfs4_client *clp;

fs/nfs/delegation.h

@@ -30,6 +30,7 @@ int nfs_async_inode_return_delegation(struct inode *inode, const nfs4_stateid *s
 
 struct inode *nfs_delegation_find_inode(struct nfs4_client *clp, const struct nfs_fh *fhandle);
 void nfs_return_all_delegations(struct super_block *sb);
+void nfs_handle_cb_pathdown(struct nfs4_client *clp);
 
 void nfs_delegation_mark_reclaim(struct nfs4_client *clp);
 void nfs_delegation_reap_unclaimed(struct nfs4_client *clp);

fs/nfs/nfs4proc.c

@@ -1940,9 +1940,11 @@ renew_done(struct rpc_task *task)
 	if (task->tk_status < 0) {
 		switch (task->tk_status) {
 			case -NFS4ERR_STALE_CLIENTID:
+			case -NFS4ERR_EXPIRED:
+			case -NFS4ERR_CB_PATH_DOWN:
 				nfs4_schedule_state_recovery(clp);
-				return;
 		}
+		return;
 	}
 	spin_lock(&clp->cl_lock);
 	if (time_before(clp->cl_last_renewal,timestamp))
@@ -1975,11 +1977,13 @@ nfs4_proc_renew(struct nfs4_client *clp)
 	int status;
 
 	status = rpc_call_sync(clp->cl_rpcclient, &msg, 0);
+	if (status < 0)
+		return status;
 	spin_lock(&clp->cl_lock);
 	if (time_before(clp->cl_last_renewal,now))
 		clp->cl_last_renewal = now;
 	spin_unlock(&clp->cl_lock);
-	return status;
+	return 0;
 }
 
 /*

fs/nfs/nfs4state.c

@@ -842,7 +842,7 @@ static int reclaimer(void *ptr)
 	struct reclaimer_args *args = (struct reclaimer_args *)ptr;
 	struct nfs4_client *clp = args->clp;
 	struct nfs4_state_owner *sp;
-	int status;
+	int status = 0;
 
 	daemonize("%u.%u.%u.%u-reclaim", NIPQUAD(clp->cl_addr));
 	allow_signal(SIGKILL);
@@ -858,7 +858,7 @@ static int reclaimer(void *ptr)
 		goto out;
 restart_loop:
 	status = nfs4_proc_renew(clp);
-	if (status == 0)
+	if (status == 0 || status == -NFS4ERR_CB_PATH_DOWN)
 		goto out;
 	status = nfs4_init_client(clp);
 	if (status)
@@ -881,6 +881,8 @@ static int reclaimer(void *ptr)
 	unlock_kernel();
 	wake_up_all(&clp->cl_waitq);
 	rpc_wake_up(&clp->cl_rpcwaitq);
+	if (status == -NFS4ERR_CB_PATH_DOWN)
+		nfs_handle_cb_pathdown(clp);
 	nfs4_put_client(clp);
 	return 0;
 out_error: