nfsd4: allow nfs4 state startup to fail

The failure here is pretty unlikely, but we should handle it anyway.
Signed-off-by: J. Bruce Fields <bfields@citi.umich.edu>

fs/nfsd/nfs4state.c

@@ -4004,7 +4004,7 @@ set_max_delegations(void)
 
 /* initialization to perform when the nfsd service is started: */
 
-static void
+static int
 __nfs4_state_start(void)
 {
 	unsigned long grace_time;
@@ -4016,19 +4016,26 @@ __nfs4_state_start(void)
 	printk(KERN_INFO "NFSD: starting %ld-second grace period\n",
 	       grace_time/HZ);
 	laundry_wq = create_singlethread_workqueue("nfsd4");
+	if (laundry_wq == NULL)
+		return -ENOMEM;
 	queue_delayed_work(laundry_wq, &laundromat_work, grace_time);
 	set_max_delegations();
+	return 0;
 }
 
-void
+int
 nfs4_state_start(void)
 {
+	int ret;
+
 	if (nfs4_init)
-		return;
+		return 0;
 	nfsd4_load_reboot_recovery_data();
-	__nfs4_state_start();
+	ret = __nfs4_state_start();
+	if (ret)
+		return ret;
 	nfs4_init = 1;
-	return;
+	return 0;
 }
 
 time_t

fs/nfsd/nfssvc.c

@@ -411,7 +411,9 @@ nfsd_svc(unsigned short port, int nrservs)
 	error =	nfsd_racache_init(2*nrservs);
 	if (error<0)
 		goto out;
-	nfs4_state_start();
+	error = nfs4_state_start();
+	if (error)
+		goto out;
 
 	nfsd_reset_versions();
 

include/linux/nfsd/nfsd.h

@@ -166,7 +166,7 @@ extern int nfsd_max_blksize;
 extern unsigned int max_delegations;
 int nfs4_state_init(void);
 void nfsd4_free_slabs(void);
-void nfs4_state_start(void);
+int nfs4_state_start(void);
 void nfs4_state_shutdown(void);
 time_t nfs4_lease_time(void);
 void nfs4_reset_lease(time_t leasetime);
@@ -174,7 +174,7 @@ int nfs4_reset_recoverydir(char *recdir);
 #else
 static inline int nfs4_state_init(void) { return 0; }
 static inline void nfsd4_free_slabs(void) { }
-static inline void nfs4_state_start(void) { }
+static inline int nfs4_state_start(void) { }
 static inline void nfs4_state_shutdown(void) { }
 static inline time_t nfs4_lease_time(void) { return 0; }
 static inline void nfs4_reset_lease(time_t leasetime) { }