nfp: flower: add GRE decap classification support

Extend the existing tunnel matching support to include GRE decap
classification. Specifically matching existing tunnel fields for
NVGRE (GRE with protocol field set to TEB).

Signed-off-by: Pieter Jansen van Vuuren <pieter.jansenvanvuuren@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: John Hurley <john.hurley@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 41 insertions, 18 deletions

diff --git a/drivers/net/ethernet/netronome/nfp/flower/offload.c b/drivers/net/ethernet/netronome/nfp/flower/offload.c
index 6b28910442db..6dbe947269c3 100644
--- a/drivers/net/ethernet/netronome/nfp/flower/offload.c
+++ b/drivers/net/ethernet/netronome/nfp/flower/offload.c
@@ -52,8 +52,7 @@
 
 #define NFP_FLOWER_WHITELIST_TUN_DISSECTOR_R \
 	(BIT(FLOW_DISSECTOR_KEY_ENC_CONTROL) | \
-	 BIT(FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS) | \
-	 BIT(FLOW_DISSECTOR_KEY_ENC_PORTS))
+	 BIT(FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS))
 
 #define NFP_FLOWER_MERGE_FIELDS \
 	(NFP_FLOWER_LAYER_PORT | \
@@ -285,27 +284,51 @@ nfp_flower_calculate_key_layers(struct nfp_app *app,
 			return -EOPNOTSUPP;
 		}
 
-		flow_rule_match_enc_ports(rule, &enc_ports);
-		if (enc_ports.mask->dst != cpu_to_be16(~0)) {
-			NL_SET_ERR_MSG_MOD(extack, "unsupported offload: only an exact match L4 destination port is supported");
-			return -EOPNOTSUPP;
-		}
-
 		if (flow_rule_match_key(rule, FLOW_DISSECTOR_KEY_ENC_OPTS))
 			flow_rule_match_enc_opts(rule, &enc_op);
 
 
-		err = nfp_flower_calc_udp_tun_layer(enc_ports.key, enc_op.key,
-						    &key_layer_two, &key_layer,
-						    &key_size, priv, tun_type,
-						    extack);
-		if (err)
-			return err;
+		if (!flow_rule_match_key(rule, FLOW_DISSECTOR_KEY_ENC_PORTS)) {
+			/* check if GRE, which has no enc_ports */
+			if (netif_is_gretap(netdev)) {
+				*tun_type = NFP_FL_TUNNEL_GRE;
+				key_layer |= NFP_FLOWER_LAYER_EXT_META;
+				key_size += sizeof(struct nfp_flower_ext_meta);
+				key_layer_two |= NFP_FLOWER_LAYER2_GRE;
+				key_size +=
+					sizeof(struct nfp_flower_ipv4_gre_tun);
+
+				if (enc_op.key) {
+					NL_SET_ERR_MSG_MOD(extack, "unsupported offload: encap options not supported on GRE tunnels");
+					return -EOPNOTSUPP;
+				}
+			} else {
+				NL_SET_ERR_MSG_MOD(extack, "unsupported offload: an exact match on L4 destination port is required for non-GRE tunnels");
+				return -EOPNOTSUPP;
+			}
+		} else {
+			flow_rule_match_enc_ports(rule, &enc_ports);
+			if (enc_ports.mask->dst != cpu_to_be16(~0)) {
+				NL_SET_ERR_MSG_MOD(extack, "unsupported offload: only an exact match L4 destination port is supported");
+				return -EOPNOTSUPP;
+			}
 
-		/* Ensure the ingress netdev matches the expected tun type. */
-		if (!nfp_fl_netdev_is_tunnel_type(netdev, *tun_type)) {
-			NL_SET_ERR_MSG_MOD(extack, "unsupported offload: ingress netdev does not match the expected tunnel type");
-			return -EOPNOTSUPP;
+			err = nfp_flower_calc_udp_tun_layer(enc_ports.key,
+							    enc_op.key,
+							    &key_layer_two,
+							    &key_layer,
+							    &key_size, priv,
+							    tun_type, extack);
+			if (err)
+				return err;
+
+			/* Ensure the ingress netdev matches the expected
+			 * tun type.
+			 */
+			if (!nfp_fl_netdev_is_tunnel_type(netdev, *tun_type)) {
+				NL_SET_ERR_MSG_MOD(extack, "unsupported offload: ingress netdev does not match the expected tunnel type");
+				return -EOPNOTSUPP;
+			}
 		}
 	}