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>

fs/dlm/dlm_internal.h

@@ -473,7 +473,6 @@ struct dlm_ls {
 	int			ls_low_nodeid;
 	int			ls_total_weight;
 	int			*ls_node_array;
-	gfp_t			ls_allocation;
 
 	struct dlm_rsb		ls_stub_rsb;	/* for returning errors */
 	struct dlm_lkb		ls_stub_lkb;	/* for returning errors */