net/mlx5e: Disallow tc redirect offload cases we don't support

After changing the parent_id to be the same for both NICs of same
the hardware device, netdev_port_same_parent_id now returns true for
more cases (all the lower devices in the hierarchy are on the same
hardware device).

If merged eswitch isn't enabled, these cases aren't supported, so disallow
them.
Signed-off-by: NPaul Blakey <paulb@mellanox.com>
Reviewed-by: NRoi Dayan <roid@mellanox.com>
Signed-off-by: NSaeed Mahameed <saeedm@mellanox.com>

drivers/net/ethernet/mellanox/mlx5/core/en/tc_tun.c

@@ -5,6 +5,7 @@
 #include <net/gre.h>
 #include <net/geneve.h>
 #include "en/tc_tun.h"
+#include "en_tc.h"
 
 struct mlx5e_tc_tunnel *mlx5e_get_tc_tun(struct net_device *tunnel_dev)
 {
@@ -47,7 +48,8 @@ static int get_route_and_out_devs(struct mlx5e_priv *priv,
 		*route_dev = dev;
 		if (is_vlan_dev(*route_dev))
 			*out_dev = uplink_dev;
-		else if (mlx5e_eswitch_rep(dev))
+		else if (mlx5e_eswitch_rep(dev) &&
+			 mlx5e_is_valid_eswitch_fwd_dev(priv, dev))
 			*out_dev = *route_dev;
 		else
 			return -EOPNOTSUPP;

drivers/net/ethernet/mellanox/mlx5/core/en_tc.c

@@ -2802,6 +2802,16 @@ static int add_vlan_pop_action(struct mlx5e_priv *priv,
 	return err;
 }
 
+bool mlx5e_is_valid_eswitch_fwd_dev(struct mlx5e_priv *priv,
+				    struct net_device *out_dev)
+{
+	if (is_merged_eswitch_dev(priv, out_dev))
+		return true;
+
+	return mlx5e_eswitch_rep(out_dev) &&
+	       same_hw_devs(priv, netdev_priv(out_dev));
+}
+
 static int parse_tc_fdb_actions(struct mlx5e_priv *priv,
 				struct flow_action *flow_action,
 				struct mlx5e_tc_flow *flow,
@@ -2867,9 +2877,7 @@ static int parse_tc_fdb_actions(struct mlx5e_priv *priv,
 
 			action |= MLX5_FLOW_CONTEXT_ACTION_FWD_DEST |
 				  MLX5_FLOW_CONTEXT_ACTION_COUNT;
-			if (netdev_port_same_parent_id(priv->netdev,
-						       out_dev) ||
-			    is_merged_eswitch_dev(priv, out_dev)) {
+			if (netdev_port_same_parent_id(priv->netdev, out_dev)) {
 				struct mlx5_eswitch *esw = priv->mdev->priv.eswitch;
 				struct net_device *uplink_dev = mlx5_eswitch_uplink_get_proto_dev(esw, REP_ETH);
 				struct net_device *uplink_upper = netdev_master_upper_dev_get(uplink_dev);
@@ -2886,6 +2894,7 @@ static int parse_tc_fdb_actions(struct mlx5e_priv *priv,
 					if (err)
 						return err;
 				}
+
 				if (is_vlan_dev(parse_attr->filter_dev)) {
 					err = add_vlan_pop_action(priv, attr,
 								  &action);
@@ -2893,8 +2902,13 @@ static int parse_tc_fdb_actions(struct mlx5e_priv *priv,
 						return err;
 				}
 
-				if (!mlx5e_eswitch_rep(out_dev))
+				if (!mlx5e_is_valid_eswitch_fwd_dev(priv, out_dev)) {
+					NL_SET_ERR_MSG_MOD(extack,
+							   "devices are not on same switch HW, can't offload forwarding");
+					pr_err("devices %s %s not on same switch HW, can't offload forwarding\n",
+					       priv->netdev->name, out_dev->name);
 					return -EOPNOTSUPP;
+				}
 
 				out_priv = netdev_priv(out_dev);
 				rpriv = out_priv->ppriv;

drivers/net/ethernet/mellanox/mlx5/core/en_tc.h

@@ -74,6 +74,9 @@ int mlx5e_tc_num_filters(struct mlx5e_priv *priv, int flags);
 
 void mlx5e_tc_reoffload_flows_work(struct work_struct *work);
 
+bool mlx5e_is_valid_eswitch_fwd_dev(struct mlx5e_priv *priv,
+				    struct net_device *out_dev);
+
 #else /* CONFIG_MLX5_ESWITCH */
 static inline int  mlx5e_tc_nic_init(struct mlx5e_priv *priv) { return 0; }
 static inline void mlx5e_tc_nic_cleanup(struct mlx5e_priv *priv) {}