mlxsw: spectrum_router: Add gateway indication to nexthop group

The next patch is going to generalize the way in which we store routes.
Instead of attaching a nexthop group only to gatewayed routes, one will
be attached to each route, in a similar way to the way the FIB code
stores its routes.

The above means that any function operating on a nexthop group cannot
assume the group represents only gatewayed nexthops. One such function
is the one that refreshes a nexthop group and updates the adjacency
table following nexthop changes.

For a nexthop group that doesn't represent any gateways this function
would essentially be a NOP, but it would be useful if it did update the
action associated with any route using it. This will allow us to later
consolidate code paths when a nexthop changes following NH_{ADD,DEL}
events.
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/mellanox/mlxsw/spectrum_router.c

@@ -1121,7 +1121,8 @@ struct mlxsw_sp_nexthop_group {
 	struct rhash_head ht_node;
 	struct list_head fib_list; /* list of fib entries that use this group */
 	struct mlxsw_sp_nexthop_group_key key;
-	u8 adj_index_valid:1;
+	u8 adj_index_valid:1,
+	   gateway:1; /* routes using the group use a gateway */
 	u32 adj_index;
 	u16 ecmp_size;
 	u16 count;
@@ -1292,6 +1293,11 @@ mlxsw_sp_nexthop_group_refresh(struct mlxsw_sp *mlxsw_sp,
 	int i;
 	int err;
 
+	if (!nh_grp->gateway) {
+		mlxsw_sp_nexthop_fib_entries_update(mlxsw_sp, nh_grp);
+		return;
+	}
+
 	for (i = 0; i < nh_grp->count; i++) {
 		nh = &nh_grp->nexthops[i];
 
@@ -1505,6 +1511,7 @@ mlxsw_sp_nexthop_group_create(struct mlxsw_sp *mlxsw_sp, struct fib_info *fi)
 	if (!nh_grp)
 		return ERR_PTR(-ENOMEM);
 	INIT_LIST_HEAD(&nh_grp->fib_list);
+	nh_grp->gateway = fi->fib_nh->nh_scope == RT_SCOPE_LINK;
 	nh_grp->count = fi->fib_nhs;
 	nh_grp->key.fi = fi;
 	for (i = 0; i < nh_grp->count; i++) {