[PATCH net-next,1/3] hv_netvsc: Change the hash level variable to bit flags

[Haiyang Zhang <haiyangz@exchange.microsoft.com>]

From: Haiyang Zhang <haiyangz@microsoft.com>

This simplifies the logic and make it easier to add more
options.

Signed-off-by: Haiyang Zhang <haiyangz@microsoft.com>
---
 drivers/net/hyperv/hyperv_net.h | 11 +++++--
 drivers/net/hyperv/netvsc_drv.c | 73 ++++++++++++++++++++++++++++-------------
 2 files changed, 59 insertions(+), 25 deletions(-)

diff --git a/drivers/net/hyperv/hyperv_net.h b/drivers/net/hyperv/hyperv_net.h
index 6f550e15a41c..a81335e8ebe8 100644
--- a/drivers/net/hyperv/hyperv_net.h
+++ b/drivers/net/hyperv/hyperv_net.h
@@ -704,6 +704,14 @@ struct netvsc_reconfig {
 	u32 event;
 };
 
+/* L4 hash bits for different protocols */
+#define HV_TCP4_L4HASH 1
+#define HV_TCP6_L4HASH 2
+#define HV_UDP4_L4HASH 4
+#define HV_UDP6_L4HASH 8
+#define HV_DEFAULT_L4HASH (HV_TCP4_L4HASH | HV_TCP6_L4HASH | HV_UDP4_L4HASH | \
+			   HV_UDP6_L4HASH)
+
 /* The context of the netvsc device  */
 struct net_device_context {
 	/* point back to our device context */
@@ -726,10 +734,9 @@ struct net_device_context {
 	u32 tx_send_table[VRSS_SEND_TAB_SIZE];
 
 	/* Ethtool settings */
-	bool udp4_l4_hash;
-	bool udp6_l4_hash;
 	u8 duplex;
 	u32 speed;
+	u32 l4_hash; /* L4 hash settings */
 	struct netvsc_ethtool_stats eth_stats;
 
 	/* State to manage the associated VF interface. */
diff --git a/drivers/net/hyperv/netvsc_drv.c b/drivers/net/hyperv/netvsc_drv.c
index dfb986421ec6..9bc7dbab9506 100644
--- a/drivers/net/hyperv/netvsc_drv.c
+++ b/drivers/net/hyperv/netvsc_drv.c
@@ -203,7 +203,7 @@ static inline u32 netvsc_get_hash(
 	const struct net_device_context *ndc)
 {
 	struct flow_keys flow;
-	u32 hash;
+	u32 hash, pkt_proto = 0;
 	static u32 hashrnd __read_mostly;
 
 	net_get_random_once(&hashrnd, sizeof(hashrnd));
@@ -211,11 +211,25 @@ static inline u32 netvsc_get_hash(
 	if (!skb_flow_dissect_flow_keys(skb, &flow, 0))
 		return 0;
 
-	if (flow.basic.ip_proto == IPPROTO_TCP ||
-	    (flow.basic.ip_proto == IPPROTO_UDP &&
-	     ((flow.basic.n_proto == htons(ETH_P_IP) && ndc->udp4_l4_hash) ||
-	      (flow.basic.n_proto == htons(ETH_P_IPV6) &&
-	       ndc->udp6_l4_hash)))) {
+	switch (flow.basic.ip_proto) {
+	case IPPROTO_TCP:
+		if (flow.basic.n_proto == htons(ETH_P_IP))
+			pkt_proto = HV_TCP4_L4HASH;
+		else if (flow.basic.n_proto == htons(ETH_P_IPV6))
+			pkt_proto = HV_TCP6_L4HASH;
+
+		break;
+
+	case IPPROTO_UDP:
+		if (flow.basic.n_proto == htons(ETH_P_IP))
+			pkt_proto = HV_UDP4_L4HASH;
+		else if (flow.basic.n_proto == htons(ETH_P_IPV6))
+			pkt_proto = HV_UDP6_L4HASH;
+
+		break;
+	}
+
+	if (pkt_proto & ndc->l4_hash) {
 		return skb_get_hash(skb);
 	} else {
 		if (flow.basic.n_proto == htons(ETH_P_IP))
@@ -898,8 +912,7 @@ static void netvsc_init_settings(struct net_device *dev)
 {
 	struct net_device_context *ndc = netdev_priv(dev);
 
-	ndc->udp4_l4_hash = true;
-	ndc->udp6_l4_hash = true;
+	ndc->l4_hash = HV_DEFAULT_L4HASH;
 
 	ndc->speed = SPEED_UNKNOWN;
 	ndc->duplex = DUPLEX_FULL;
@@ -1245,23 +1258,25 @@ static int
 netvsc_get_rss_hash_opts(struct net_device_context *ndc,
 			 struct ethtool_rxnfc *info)
 {
+	const u32 l4_flag = RXH_L4_B_0_1 | RXH_L4_B_2_3;
+
 	info->data = RXH_IP_SRC | RXH_IP_DST;
 
 	switch (info->flow_type) {
 	case TCP_V4_FLOW:
 	case TCP_V6_FLOW:
-		info->data |= RXH_L4_B_0_1 | RXH_L4_B_2_3;
+		info->data |= l4_flag;
 		break;
 
 	case UDP_V4_FLOW:
-		if (ndc->udp4_l4_hash)
-			info->data |= RXH_L4_B_0_1 | RXH_L4_B_2_3;
+		if (ndc->l4_hash & HV_UDP4_L4HASH)
+			info->data |= l4_flag;
 
 		break;
 
 	case UDP_V6_FLOW:
-		if (ndc->udp6_l4_hash)
-			info->data |= RXH_L4_B_0_1 | RXH_L4_B_2_3;
+		if (ndc->l4_hash & HV_UDP6_L4HASH)
+			info->data |= l4_flag;
 
 		break;
 
@@ -1302,23 +1317,35 @@ static int netvsc_set_rss_hash_opts(struct net_device_context *ndc,
 {
 	if (info->data == (RXH_IP_SRC | RXH_IP_DST |
 			   RXH_L4_B_0_1 | RXH_L4_B_2_3)) {
-		if (info->flow_type == UDP_V4_FLOW)
-			ndc->udp4_l4_hash = true;
-		else if (info->flow_type == UDP_V6_FLOW)
-			ndc->udp6_l4_hash = true;
-		else
+		switch (info->flow_type) {
+		case UDP_V4_FLOW:
+			ndc->l4_hash |= HV_UDP4_L4HASH;
+			break;
+
+		case UDP_V6_FLOW:
+			ndc->l4_hash |= HV_UDP6_L4HASH;
+			break;
+
+		default:
 			return -EOPNOTSUPP;
+		}
 
 		return 0;
 	}
 
 	if (info->data == (RXH_IP_SRC | RXH_IP_DST)) {
-		if (info->flow_type == UDP_V4_FLOW)
-			ndc->udp4_l4_hash = false;
-		else if (info->flow_type == UDP_V6_FLOW)
-			ndc->udp6_l4_hash = false;
-		else
+		switch (info->flow_type) {
+		case UDP_V4_FLOW:
+			ndc->l4_hash &= ~HV_UDP4_L4HASH;
+			break;
+
+		case UDP_V6_FLOW:
+			ndc->l4_hash &= ~HV_UDP6_L4HASH;
+			break;
+
+		default:
 			return -EOPNOTSUPP;
+		}
 
 		return 0;
 	}
-- 
2.14.1