mlxsw: spectrum_flower: Fail in case user specifies multiple mirror actions

The ASIC can only mirror a packet to one port, but when user is trying
to set more than one mirror action, it doesn't fail.

Add a check if more than one mirror action was specified per rule and if so,
fail for not being supported.

Fixes: d0d13c18 ("mlxsw: spectrum_acl: Add support for mirror action")
Signed-off-by: Danielle Ratson <danieller@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

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

@@ -21,6 +21,7 @@ static int mlxsw_sp_flower_parse_actions(struct mlxsw_sp *mlxsw_sp,
 					 struct netlink_ext_ack *extack)
 {
 	const struct flow_action_entry *act;
+	int mirror_act_count = 0;
 	int err, i;
 
 	if (!flow_action_has_entries(flow_action))
@@ -105,6 +106,11 @@ static int mlxsw_sp_flower_parse_actions(struct mlxsw_sp *mlxsw_sp,
 		case FLOW_ACTION_MIRRED: {
 			struct net_device *out_dev = act->dev;
 
+			if (mirror_act_count++) {
+				NL_SET_ERR_MSG_MOD(extack, "Multiple mirror actions per rule are not supported");
+				return -EOPNOTSUPP;
+			}
+
 			err = mlxsw_sp_acl_rulei_act_mirror(mlxsw_sp, rulei,
 							    block, out_dev,
 							    extack);