mlxsw: spectrum_router: Handle down of tunnel underlay

When the bound device of a tunnel device is down, encapsulated packets
are not egressed anymore, but tunnel decap still works. Extend
mlxsw_sp_nexthop_rif_update() to take IFF_UP into consideration when
deciding whether a given next hop should be offloaded.

Because the new logic was added to mlxsw_sp_nexthop_rif_update(), this
fixes the case where a newly-added tunnel has a down bound device, which
would previously be fully offloaded. Now the down state of the bound
device is noted and next hops forwarding to such tunnel are not
offloaded.

In addition to that, notice NETDEV_UP and NETDEV_DOWN of a bound device
to force refresh of tunnel encap route offloads.

Signed-off-by: Petr Machata <petrm@mellanox.com>
Reviewed-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

@@ -1466,6 +1466,28 @@ mlxsw_sp_netdevice_ipip_ul_vrf_event(struct mlxsw_sp *mlxsw_sp,
 						   true, true, false, extack);
 }
 
+static int
+mlxsw_sp_netdevice_ipip_ul_up_event(struct mlxsw_sp *mlxsw_sp,
+				    struct mlxsw_sp_ipip_entry *ipip_entry,
+				    struct net_device *ul_dev)
+{
+	return __mlxsw_sp_ipip_entry_update_tunnel(mlxsw_sp, ipip_entry,
+						   false, false, true, NULL);
+}
+
+static int
+mlxsw_sp_netdevice_ipip_ul_down_event(struct mlxsw_sp *mlxsw_sp,
+				      struct mlxsw_sp_ipip_entry *ipip_entry,
+				      struct net_device *ul_dev)
+{
+	/* A down underlay device causes encapsulated packets to not be
+	 * forwarded, but decap still works. So refresh next hops without
+	 * touching anything else.
+	 */
+	return __mlxsw_sp_ipip_entry_update_tunnel(mlxsw_sp, ipip_entry,
+						   false, false, true, NULL);
+}
+
 static int
 mlxsw_sp_netdevice_ipip_ol_change_event(struct mlxsw_sp *mlxsw_sp,
 					struct net_device *ol_dev,
@@ -1604,6 +1626,14 @@ __mlxsw_sp_netdevice_ipip_ul_event(struct mlxsw_sp *mlxsw_sp,
 								    ul_dev,
 								    extack);
 		break;
+
+	case NETDEV_UP:
+		return mlxsw_sp_netdevice_ipip_ul_up_event(mlxsw_sp, ipip_entry,
+							   ul_dev);
+	case NETDEV_DOWN:
+		return mlxsw_sp_netdevice_ipip_ul_down_event(mlxsw_sp,
+							     ipip_entry,
+							     ul_dev);
 	}
 	return 0;
 }
@@ -3297,10 +3327,19 @@ static void mlxsw_sp_nexthop_neigh_fini(struct mlxsw_sp *mlxsw_sp,
 	neigh_release(n);
 }
 
+static bool mlxsw_sp_ipip_netdev_ul_up(struct net_device *ol_dev)
+{
+	struct net_device *ul_dev = __mlxsw_sp_ipip_netdev_ul_dev_get(ol_dev);
+
+	return ul_dev ? (ul_dev->flags & IFF_UP) : true;
+}
+
 static int mlxsw_sp_nexthop_ipip_init(struct mlxsw_sp *mlxsw_sp,
 				      struct mlxsw_sp_nexthop *nh,
 				      struct net_device *ol_dev)
 {
+	bool removing;
+
 	if (!nh->nh_grp->gateway || nh->ipip_entry)
 		return 0;
 
@@ -3308,7 +3347,8 @@ static int mlxsw_sp_nexthop_ipip_init(struct mlxsw_sp *mlxsw_sp,
 	if (!nh->ipip_entry)
 		return -ENOENT;
 
-	__mlxsw_sp_nexthop_neigh_update(nh, false);
+	removing = !mlxsw_sp_ipip_netdev_ul_up(ol_dev);
+	__mlxsw_sp_nexthop_neigh_update(nh, removing);
 	return 0;
 }
 
@@ -3476,9 +3516,22 @@ static void mlxsw_sp_nexthop_rif_update(struct mlxsw_sp *mlxsw_sp,
 					struct mlxsw_sp_rif *rif)
 {
 	struct mlxsw_sp_nexthop *nh;
+	bool removing;
 
 	list_for_each_entry(nh, &rif->nexthop_list, rif_list_node) {
-		__mlxsw_sp_nexthop_neigh_update(nh, false);
+		switch (nh->type) {
+		case MLXSW_SP_NEXTHOP_TYPE_ETH:
+			removing = false;
+			break;
+		case MLXSW_SP_NEXTHOP_TYPE_IPIP:
+			removing = !mlxsw_sp_ipip_netdev_ul_up(rif->dev);
+			break;
+		default:
+			WARN_ON(1);
+			continue;
+		}
+
+		__mlxsw_sp_nexthop_neigh_update(nh, removing);
 		mlxsw_sp_nexthop_group_refresh(mlxsw_sp, nh->nh_grp);
 	}
 }