dlm: always use GFP_NOFS

Replace all GFP_KERNEL and ls_allocation with GFP_NOFS.
ls_allocation would be GFP_KERNEL for userland lockspaces
and GFP_NOFS for file system lockspaces.

It was discovered that any lockspaces on the system can
affect all others by triggering memory reclaim in the
file system which could in turn call back into the dlm
to acquire locks, deadlocking dlm threads that were
shared by all lockspaces, like dlm_recv.

Signed-off-by: David Teigland <teigland@redhat.com>
diff --git a/fs/dlm/lowcomms.c b/fs/dlm/lowcomms.c
index 70736eb..52cab16 100644
--- a/fs/dlm/lowcomms.c
+++ b/fs/dlm/lowcomms.c
@@ -1060,7 +1060,7 @@
 		if (dlm_our_addr(&sas, i))
 			break;
 
-		addr = kmalloc(sizeof(*addr), GFP_KERNEL);
+		addr = kmalloc(sizeof(*addr), GFP_NOFS);
 		if (!addr)
 			break;
 		memcpy(addr, &sas, sizeof(*addr));
@@ -1099,7 +1099,7 @@
 	struct sockaddr_storage localaddr;
 	struct sctp_event_subscribe subscribe;
 	int result = -EINVAL, num = 1, i, addr_len;
-	struct connection *con = nodeid2con(0, GFP_KERNEL);
+	struct connection *con = nodeid2con(0, GFP_NOFS);
 	int bufsize = NEEDED_RMEM;
 
 	if (!con)
@@ -1171,7 +1171,7 @@
 static int tcp_listen_for_all(void)
 {
 	struct socket *sock = NULL;
-	struct connection *con = nodeid2con(0, GFP_KERNEL);
+	struct connection *con = nodeid2con(0, GFP_NOFS);
 	int result = -EINVAL;
 
 	if (!con)