lockd: NLM grace period shouldn't block NFSv4 opens

NLM locks don't conflict with NFSv4 share reservations, so we're not
going to learn anything new by watiting for them.

They do conflict with NFSv4 locks and with delegations.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
diff --git a/fs/nfsd/nfs4state.c b/fs/nfsd/nfs4state.c
index 43903ab..c0c47a8 100644
--- a/fs/nfsd/nfs4state.c
+++ b/fs/nfsd/nfs4state.c
@@ -4065,7 +4065,8 @@
 		case NFS4_OPEN_CLAIM_FH:
 			/*
 			 * Let's not give out any delegations till everyone's
-			 * had the chance to reclaim theirs....
+			 * had the chance to reclaim theirs, *and* until
+			 * NLM locks have all been reclaimed:
 			 */
 			if (locks_in_grace(clp->net))
 				goto out_no_deleg;
@@ -4440,7 +4441,7 @@
 {
 	if (ONE_STATEID(stateid) && (flags & RD_STATE))
 		return nfs_ok;
-	else if (locks_in_grace(net)) {
+	else if (opens_in_grace(net)) {
 		/* Answer in remaining cases depends on existence of
 		 * conflicting state; so we must wait out the grace period. */
 		return nfserr_grace;
@@ -4459,7 +4460,7 @@
 static inline int
 grace_disallows_io(struct net *net, struct inode *inode)
 {
-	return locks_in_grace(net) && mandatory_lock(inode);
+	return opens_in_grace(net) && mandatory_lock(inode);
 }
 
 /* Returns true iff a is later than b: */
@@ -6578,6 +6579,7 @@
 		return ret;
 	nn->boot_time = get_seconds();
 	nn->grace_ended = false;
+	nn->nfsd4_manager.block_opens = true;
 	locks_start_grace(net, &nn->nfsd4_manager);
 	nfsd4_client_tracking_init(net);
 	printk(KERN_INFO "NFSD: starting %ld-second grace period (net %p)\n",