nfp: flower: remove unused tun_mask variable

The tunnel dest IP is required for separate offload to the NFP. It is
already verified that a dest IP must be present and must be an exact
match in the flower rule. Therefore, we can just extract the IP from the
generated offload rule and remove the unused mask variable. The function
is then no longer required to return the IP separately.

Because tun_dst is localised to tunnel matches, move the declaration to
the tunnel if branch.
Signed-off-by: John Hurley <john.hurley@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/ethernet/netronome/nfp/flower/match.c

@@ -218,7 +218,7 @@ nfp_flower_compile_ipv6(struct nfp_flower_ipv6 *frame,
 static void
 nfp_flower_compile_vxlan(struct nfp_flower_vxlan *frame,
 			 struct tc_cls_flower_offload *flow,
-			 bool mask_version, __be32 *tun_dst)
+			 bool mask_version)
 {
 	struct fl_flow_key *target = mask_version ? flow->mask : flow->key;
 	struct flow_dissector_key_ipv4_addrs *vxlan_ips;
@@ -246,7 +246,6 @@ nfp_flower_compile_vxlan(struct nfp_flower_vxlan *frame,
 					     target);
 		frame->ip_src = vxlan_ips->src;
 		frame->ip_dst = vxlan_ips->dst;
-		*tun_dst = vxlan_ips->dst;
 	}
 }
 
@@ -256,7 +255,6 @@ int nfp_flower_compile_flow_match(struct tc_cls_flower_offload *flow,
 				  struct nfp_fl_payload *nfp_flow)
 {
 	enum nfp_flower_tun_type tun_type = NFP_FL_TUNNEL_NONE;
-	__be32 tun_dst, tun_dst_mask = 0;
 	struct nfp_repr *netdev_repr;
 	int err;
 	u8 *ext;
@@ -342,12 +340,15 @@ int nfp_flower_compile_flow_match(struct tc_cls_flower_offload *flow,
 	}
 
 	if (key_ls->key_layer & NFP_FLOWER_LAYER_VXLAN) {
+		__be32 tun_dst;
+
 		/* Populate Exact VXLAN Data. */
 		nfp_flower_compile_vxlan((struct nfp_flower_vxlan *)ext,
-					 flow, false, &tun_dst);
+					 flow, false);
 		/* Populate Mask VXLAN Data. */
 		nfp_flower_compile_vxlan((struct nfp_flower_vxlan *)msk,
-					 flow, true, &tun_dst_mask);
+					 flow, true);
+		tun_dst = ((struct nfp_flower_vxlan *)ext)->ip_dst;
 		ext += sizeof(struct nfp_flower_vxlan);
 		msk += sizeof(struct nfp_flower_vxlan);