nfsd: clean up grace period on early exit

If nfsd was shut down before the grace period ended, we could end up
with a freed object still on grace_list.  Thanks to Jeff Moyer for
reporting the resulting list corruption warnings.
Signed-off-by: NJ. Bruce Fields <bfields@citi.umich.edu>
Tested-by: NJeff Moyer <jmoyer@redhat.com>

fs/lockd/svc.c

@@ -181,6 +181,7 @@ lockd(void *vrqstp)
 	}
 	flush_signals(current);
 	cancel_delayed_work_sync(&grace_period_end);
+	locks_end_grace(&lockd_manager);
 	if (nlmsvc_ops)
 		nlmsvc_invalidate_all();
 	nlm_shutdown_hosts();

fs/nfsd/nfs4state.c

@@ -3261,6 +3261,7 @@ nfs4_state_shutdown(void)
 {
 	cancel_rearming_delayed_workqueue(laundry_wq, &laundromat_work);
 	destroy_workqueue(laundry_wq);
+	locks_end_grace(&nfsd4_manager);
 	nfs4_lock_state();
 	nfs4_release_reclaim();
 	__nfs4_state_shutdown();