iavf: add RSS support for GTP protocol via ethtool

Extend the iavf driver to support Receive Side Scaling (RSS)
configuration for GTP (GPRS Tunneling Protocol) flows using ethtool.

The implementation introduces new RSS flow segment headers and hash field
definitions for various GTP encapsulations, including:

  - GTPC
  - GTPU (IP, Extension Header, Uplink, Downlink)
  - TEID-based hashing

The ethtool interface is updated to parse and apply these new flow types
and hash fields, enabling fine-grained traffic distribution for GTP-based
mobile workloads.

This enhancement improves performance and scalability for virtualized
network functions (VNFs) and user plane functions (UPFs) in 5G and LTE
deployments.

Reviewed-by: Jedrzej Jagielski <jedrzej.jagielski@intel.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

1 files changed, 96 insertions, 23 deletions

diff --git a/drivers/net/ethernet/intel/iavf/iavf_adv_rss.c b/drivers/net/ethernet/intel/iavf/iavf_adv_rss.c
index a9e1da35e248..4d12dfe1b481 100644
--- a/drivers/net/ethernet/intel/iavf/iavf_adv_rss.c
+++ b/drivers/net/ethernet/intel/iavf/iavf_adv_rss.c
@@ -91,6 +91,55 @@ iavf_fill_adv_rss_sctp_hdr(struct virtchnl_proto_hdr *hdr, u64 hash_flds)
 }
 
 /**
+ * iavf_fill_adv_rss_gtp_hdr - Fill GTP-related RSS protocol headers
+ * @proto_hdrs: pointer to the virtchnl protocol headers structure to populate
+ * @packet_hdrs: bitmask of packet header types to configure
+ * @hash_flds: RSS hash field configuration
+ *
+ * This function populates the virtchnl protocol header structure with
+ * appropriate GTP-related header types based on the specified packet_hdrs.
+ * It supports GTPC, GTPU with extension headers, and uplink/downlink PDU
+ * types. For certain GTPU types, it also appends an IPv4 header to enable
+ * hashing on the destination IP address.
+ *
+ * Return: 0 on success or -EOPNOTSUPP if the packet_hdrs value is unsupported.
+ */
+static int
+iavf_fill_adv_rss_gtp_hdr(struct virtchnl_proto_hdrs *proto_hdrs,
+			  u32 packet_hdrs, u64 hash_flds)
+{
+	struct virtchnl_proto_hdr *hdr;
+
+	hdr = &proto_hdrs->proto_hdr[proto_hdrs->count - 1];
+
+	switch (packet_hdrs & IAVF_ADV_RSS_FLOW_SEG_HDR_GTP) {
+	case IAVF_ADV_RSS_FLOW_SEG_HDR_GTPC_TEID:
+	case IAVF_ADV_RSS_FLOW_SEG_HDR_GTPC:
+		VIRTCHNL_SET_PROTO_HDR_TYPE(hdr, GTPC);
+		break;
+	case IAVF_ADV_RSS_FLOW_SEG_HDR_GTPU_EH:
+		VIRTCHNL_SET_PROTO_HDR_TYPE(hdr, GTPU_EH);
+		break;
+	case IAVF_ADV_RSS_FLOW_SEG_HDR_GTPU_UP:
+		VIRTCHNL_SET_PROTO_HDR_TYPE(hdr, GTPU_EH_PDU_UP);
+		hdr = &proto_hdrs->proto_hdr[proto_hdrs->count++];
+		iavf_fill_adv_rss_ip4_hdr(hdr, IAVF_ADV_RSS_HASH_FLD_IPV4_DA);
+		break;
+	case IAVF_ADV_RSS_FLOW_SEG_HDR_GTPU_DWN:
+		VIRTCHNL_SET_PROTO_HDR_TYPE(hdr, GTPU_EH_PDU_DWN);
+		fallthrough;
+	case IAVF_ADV_RSS_FLOW_SEG_HDR_GTPU_IP:
+		hdr = &proto_hdrs->proto_hdr[proto_hdrs->count++];
+		iavf_fill_adv_rss_ip4_hdr(hdr, IAVF_ADV_RSS_HASH_FLD_IPV4_DA);
+		break;
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	return 0;
+}
+
+/**
  * iavf_fill_adv_rss_cfg_msg - fill the RSS configuration into virtchnl message
  * @rss_cfg: the virtchnl message to be filled with RSS configuration setting
  * @packet_hdrs: the RSS configuration protocol header types
@@ -103,6 +152,8 @@ int
 iavf_fill_adv_rss_cfg_msg(struct virtchnl_rss_cfg *rss_cfg,
 			  u32 packet_hdrs, u64 hash_flds, bool symm)
 {
+	const u32 packet_l3_hdrs = packet_hdrs & IAVF_ADV_RSS_FLOW_SEG_HDR_L3;
+	const u32 packet_l4_hdrs = packet_hdrs & IAVF_ADV_RSS_FLOW_SEG_HDR_L4;
 	struct virtchnl_proto_hdrs *proto_hdrs = &rss_cfg->proto_hdrs;
 	struct virtchnl_proto_hdr *hdr;
 
@@ -113,31 +164,41 @@ iavf_fill_adv_rss_cfg_msg(struct virtchnl_rss_cfg *rss_cfg,
 
 	proto_hdrs->tunnel_level = 0;	/* always outer layer */
 
-	hdr = &proto_hdrs->proto_hdr[proto_hdrs->count++];
-	switch (packet_hdrs & IAVF_ADV_RSS_FLOW_SEG_HDR_L3) {
-	case IAVF_ADV_RSS_FLOW_SEG_HDR_IPV4:
-		iavf_fill_adv_rss_ip4_hdr(hdr, hash_flds);
-		break;
-	case IAVF_ADV_RSS_FLOW_SEG_HDR_IPV6:
-		iavf_fill_adv_rss_ip6_hdr(hdr, hash_flds);
-		break;
-	default:
-		return -EINVAL;
+	if (packet_l3_hdrs) {
+		hdr = &proto_hdrs->proto_hdr[proto_hdrs->count++];
+		switch (packet_l3_hdrs) {
+		case IAVF_ADV_RSS_FLOW_SEG_HDR_IPV4:
+			iavf_fill_adv_rss_ip4_hdr(hdr, hash_flds);
+			break;
+		case IAVF_ADV_RSS_FLOW_SEG_HDR_IPV6:
+			iavf_fill_adv_rss_ip6_hdr(hdr, hash_flds);
+			break;
+		default:
+			return -EINVAL;
+		}
 	}
 
-	hdr = &proto_hdrs->proto_hdr[proto_hdrs->count++];
-	switch (packet_hdrs & IAVF_ADV_RSS_FLOW_SEG_HDR_L4) {
-	case IAVF_ADV_RSS_FLOW_SEG_HDR_TCP:
-		iavf_fill_adv_rss_tcp_hdr(hdr, hash_flds);
-		break;
-	case IAVF_ADV_RSS_FLOW_SEG_HDR_UDP:
-		iavf_fill_adv_rss_udp_hdr(hdr, hash_flds);
-		break;
-	case IAVF_ADV_RSS_FLOW_SEG_HDR_SCTP:
-		iavf_fill_adv_rss_sctp_hdr(hdr, hash_flds);
-		break;
-	default:
-		return -EINVAL;
+	if (packet_l4_hdrs) {
+		hdr = &proto_hdrs->proto_hdr[proto_hdrs->count++];
+		switch (packet_l4_hdrs) {
+		case IAVF_ADV_RSS_FLOW_SEG_HDR_TCP:
+			iavf_fill_adv_rss_tcp_hdr(hdr, hash_flds);
+			break;
+		case IAVF_ADV_RSS_FLOW_SEG_HDR_UDP:
+			iavf_fill_adv_rss_udp_hdr(hdr, hash_flds);
+			break;
+		case IAVF_ADV_RSS_FLOW_SEG_HDR_SCTP:
+			iavf_fill_adv_rss_sctp_hdr(hdr, hash_flds);
+			break;
+		default:
+			return -EINVAL;
+		}
+	}
+
+	if (packet_hdrs & IAVF_ADV_RSS_FLOW_SEG_HDR_GTP) {
+		hdr = &proto_hdrs->proto_hdr[proto_hdrs->count++];
+		if (iavf_fill_adv_rss_gtp_hdr(proto_hdrs, packet_hdrs, hash_flds))
+			return -EINVAL;
 	}
 
 	return 0;
@@ -186,6 +247,8 @@ iavf_print_adv_rss_cfg(struct iavf_adapter *adapter, struct iavf_adv_rss *rss,
 		proto = "UDP";
 	else if (packet_hdrs & IAVF_ADV_RSS_FLOW_SEG_HDR_SCTP)
 		proto = "SCTP";
+	else if (packet_hdrs & IAVF_ADV_RSS_FLOW_SEG_HDR_GTP)
+		proto = "GTP";
 	else
 		return;
 
@@ -211,6 +274,16 @@ iavf_print_adv_rss_cfg(struct iavf_adapter *adapter, struct iavf_adv_rss *rss,
 			 IAVF_ADV_RSS_HASH_FLD_UDP_DST_PORT |
 			 IAVF_ADV_RSS_HASH_FLD_SCTP_DST_PORT))
 		strcat(hash_opt, "dst port,");
+	if (hash_flds & IAVF_ADV_RSS_HASH_FLD_GTPC_TEID)
+		strcat(hash_opt, "gtp-c,");
+	if (hash_flds & IAVF_ADV_RSS_HASH_FLD_GTPU_IP_TEID)
+		strcat(hash_opt, "gtp-u ip,");
+	if (hash_flds & IAVF_ADV_RSS_HASH_FLD_GTPU_EH_TEID)
+		strcat(hash_opt, "gtp-u ext,");
+	if (hash_flds & IAVF_ADV_RSS_HASH_FLD_GTPU_UP_TEID)
+		strcat(hash_opt, "gtp-u ul,");
+	if (hash_flds & IAVF_ADV_RSS_HASH_FLD_GTPU_DWN_TEID)
+		strcat(hash_opt, "gtp-u dl,");
 
 	if (!action)
 		action = "";