bnxt_en: don't try to offload VLAN 'modify' action

bnxt offload code currently supports only 'push' and 'pop' operation: let
.ndo_setup_tc() return -EOPNOTSUPP if VLAN 'modify' action is configured.

Fixes: 2ae7408fedfe ("bnxt_en: bnxt: add TC flower filter offload support")
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Acked-by: Sathya Perla <sathya.perla@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/broadcom/bnxt/bnxt_tc.c

@@ -75,17 +75,23 @@ static int bnxt_tc_parse_redir(struct bnxt *bp,
 	return 0;
 }
 
-static void bnxt_tc_parse_vlan(struct bnxt *bp,
-			       struct bnxt_tc_actions *actions,
-			       const struct tc_action *tc_act)
+static int bnxt_tc_parse_vlan(struct bnxt *bp,
+			      struct bnxt_tc_actions *actions,
+			      const struct tc_action *tc_act)
 {
-	if (tcf_vlan_action(tc_act) == TCA_VLAN_ACT_POP) {
+	switch (tcf_vlan_action(tc_act)) {
+	case TCA_VLAN_ACT_POP:
 		actions->flags |= BNXT_TC_ACTION_FLAG_POP_VLAN;
-	} else if (tcf_vlan_action(tc_act) == TCA_VLAN_ACT_PUSH) {
+		break;
+	case TCA_VLAN_ACT_PUSH:
 		actions->flags |= BNXT_TC_ACTION_FLAG_PUSH_VLAN;
 		actions->push_vlan_tci = htons(tcf_vlan_push_vid(tc_act));
 		actions->push_vlan_tpid = tcf_vlan_push_proto(tc_act);
+		break;
+	default:
+		return -EOPNOTSUPP;
 	}
+	return 0;
 }
 
 static int bnxt_tc_parse_tunnel_set(struct bnxt *bp,
@@ -134,7 +140,9 @@ static int bnxt_tc_parse_actions(struct bnxt *bp,
 
 		/* Push/pop VLAN */
 		if (is_tcf_vlan(tc_act)) {
-			bnxt_tc_parse_vlan(bp, actions, tc_act);
+			rc = bnxt_tc_parse_vlan(bp, actions, tc_act);
+			if (rc)
+				return rc;
 			continue;
 		}