net: Eliminate NETIF_F_GEN_CSUM and NETIF_F_V[46]_CSUM

These netif flags are unnecessary convolutions. It is more
straightforward to just use NETIF_F_HW_CSUM, NETIF_F_IP_CSUM,
and NETIF_F_IPV6_CSUM directly.

This patch also:
    - Cleans up can_checksum_protocol
    - Simplifies netdev_intersect_features

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

8 files changed, 19 insertions, 15 deletions

diff --git a/net/core/dev.c b/net/core/dev.c
index 5a3b5a404642..45b013f27625 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -6467,9 +6467,9 @@ static netdev_features_t netdev_fix_features(struct net_device *dev,
 	/* UFO needs SG and checksumming */
 	if (features & NETIF_F_UFO) {
 		/* maybe split UFO into V4 and V6? */
-		if (!((features & NETIF_F_GEN_CSUM) ||
-		    (features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))
-			    == (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
+		if (!(features & NETIF_F_HW_CSUM) &&
+		    ((features & (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM)) !=
+		     (NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM))) {
 			netdev_dbg(dev,
 				"Dropping NETIF_F_UFO since no checksum offload features.\n");
 			features &= ~NETIF_F_UFO;
@@ -7571,7 +7571,7 @@ static int dev_cpu_callback(struct notifier_block *nfb,
 netdev_features_t netdev_increment_features(netdev_features_t all,
 	netdev_features_t one, netdev_features_t mask)
 {
-	if (mask & NETIF_F_GEN_CSUM)
+	if (mask & NETIF_F_HW_CSUM)
 		mask |= NETIF_F_CSUM_MASK;
 	mask |= NETIF_F_VLAN_CHALLENGED;
 
@@ -7579,8 +7579,8 @@ netdev_features_t netdev_increment_features(netdev_features_t all,
 	all &= one | ~NETIF_F_ALL_FOR_ALL;
 
 	/* If one device supports hw checksumming, set for all. */
-	if (all & NETIF_F_GEN_CSUM)
-		all &= ~(NETIF_F_CSUM_MASK & ~NETIF_F_GEN_CSUM);
+	if (all & NETIF_F_HW_CSUM)
+		all &= ~(NETIF_F_CSUM_MASK & ~NETIF_F_HW_CSUM);
 
 	return all;
 }
diff --git a/net/core/pktgen.c b/net/core/pktgen.c
index de8d5cc5eb24..2be144498bcf 100644
--- a/net/core/pktgen.c
+++ b/net/core/pktgen.c
@@ -2898,7 +2898,7 @@ static struct sk_buff *fill_packet_ipv4(struct net_device *odev,
 
 	if (!(pkt_dev->flags & F_UDPCSUM)) {
 		skb->ip_summed = CHECKSUM_NONE;
-	} else if (odev->features & NETIF_F_V4_CSUM) {
+	} else if (odev->features & (NETIF_F_HW_CSUM | NETIF_F_IP_CSUM)) {
 		skb->ip_summed = CHECKSUM_PARTIAL;
 		skb->csum = 0;
 		udp4_hwcsum(skb, iph->saddr, iph->daddr);
@@ -3032,7 +3032,7 @@ static struct sk_buff *fill_packet_ipv6(struct net_device *odev,
 
 	if (!(pkt_dev->flags & F_UDPCSUM)) {
 		skb->ip_summed = CHECKSUM_NONE;
-	} else if (odev->features & NETIF_F_V6_CSUM) {
+	} else if (odev->features & (NETIF_F_HW_CSUM | NETIF_F_IPV6_CSUM)) {
 		skb->ip_summed = CHECKSUM_PARTIAL;
 		skb->csum_start = skb_transport_header(skb) - skb->head;
 		skb->csum_offset = offsetof(struct udphdr, check);
diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index e0b94cd843d7..568e2bc0d93d 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -911,7 +911,7 @@ static int __ip_append_data(struct sock *sk,
 	 */
 	if (transhdrlen &&
 	    length + fragheaderlen <= mtu &&
-	    rt->dst.dev->features & NETIF_F_V4_CSUM &&
+	    rt->dst.dev->features & (NETIF_F_HW_CSUM | NETIF_F_IP_CSUM) &&
 	    !(flags & MSG_MORE) &&
 	    !exthdrlen)
 		csummode = CHECKSUM_PARTIAL;
diff --git a/net/ipv4/netfilter/nf_nat_l3proto_ipv4.c b/net/ipv4/netfilter/nf_nat_l3proto_ipv4.c
index 5075b7ecd26d..61c7cc22ea68 100644
--- a/net/ipv4/netfilter/nf_nat_l3proto_ipv4.c
+++ b/net/ipv4/netfilter/nf_nat_l3proto_ipv4.c
@@ -132,7 +132,8 @@ static void nf_nat_ipv4_csum_recalc(struct sk_buff *skb,
 
 	if (skb->ip_summed != CHECKSUM_PARTIAL) {
 		if (!(rt->rt_flags & RTCF_LOCAL) &&
-		    (!skb->dev || skb->dev->features & NETIF_F_V4_CSUM)) {
+		    (!skb->dev || skb->dev->features &
+		     (NETIF_F_IP_CSUM | NETIF_F_HW_CSUM))) {
 			skb->ip_summed = CHECKSUM_PARTIAL;
 			skb->csum_start = skb_headroom(skb) +
 					  skb_network_offset(skb) +
diff --git a/net/ipv4/udp.c b/net/ipv4/udp.c
index 0c7b0e61b917..8841e984f8bf 100644
--- a/net/ipv4/udp.c
+++ b/net/ipv4/udp.c
@@ -772,7 +772,8 @@ void udp_set_csum(bool nocheck, struct sk_buff *skb,
 	else if (skb_is_gso(skb))
 		uh->check = ~udp_v4_check(len, saddr, daddr, 0);
 	else if (skb_dst(skb) && skb_dst(skb)->dev &&
-		 (skb_dst(skb)->dev->features & NETIF_F_V4_CSUM)) {
+		 (skb_dst(skb)->dev->features &
+		  (NETIF_F_IP_CSUM | NETIF_F_HW_CSUM))) {
 
 		BUG_ON(skb->ip_summed == CHECKSUM_PARTIAL);
 
diff --git a/net/ipv4/udp_offload.c b/net/ipv4/udp_offload.c
index f9386160cbee..130042660181 100644
--- a/net/ipv4/udp_offload.c
+++ b/net/ipv4/udp_offload.c
@@ -60,8 +60,9 @@ static struct sk_buff *__skb_udp_tunnel_segment(struct sk_buff *skb,
 
 	/* Try to offload checksum if possible */
 	offload_csum = !!(need_csum &&
-			  (skb->dev->features &
-			   (is_ipv6 ? NETIF_F_V6_CSUM : NETIF_F_V4_CSUM)));
+			  ((skb->dev->features & NETIF_F_HW_CSUM) ||
+			   (skb->dev->features & (is_ipv6 ?
+			    NETIF_F_IPV6_CSUM : NETIF_F_IP_CSUM))));
 
 	/* segment inner packet. */
 	enc_features = skb->dev->hw_enc_features & features;
diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index e6a7bd15b9b7..2f748452b4aa 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -1322,7 +1322,7 @@ emsgsize:
 	    headersize == sizeof(struct ipv6hdr) &&
 	    length < mtu - headersize &&
 	    !(flags & MSG_MORE) &&
-	    rt->dst.dev->features & NETIF_F_V6_CSUM)
+	    rt->dst.dev->features & (NETIF_F_IPV6_CSUM | NETIF_F_HW_CSUM))
 		csummode = CHECKSUM_PARTIAL;
 
 	if (sk->sk_type == SOCK_DGRAM || sk->sk_type == SOCK_RAW) {
diff --git a/net/ipv6/netfilter/nf_nat_l3proto_ipv6.c b/net/ipv6/netfilter/nf_nat_l3proto_ipv6.c
index 238e70c3f7b7..6ce309928841 100644
--- a/net/ipv6/netfilter/nf_nat_l3proto_ipv6.c
+++ b/net/ipv6/netfilter/nf_nat_l3proto_ipv6.c
@@ -136,7 +136,8 @@ static void nf_nat_ipv6_csum_recalc(struct sk_buff *skb,
 
 	if (skb->ip_summed != CHECKSUM_PARTIAL) {
 		if (!(rt->rt6i_flags & RTF_LOCAL) &&
-		    (!skb->dev || skb->dev->features & NETIF_F_V6_CSUM)) {
+		    (!skb->dev || skb->dev->features &
+		     (NETIF_F_IPV6_CSUM | NETIF_F_HW_CSUM))) {
 			skb->ip_summed = CHECKSUM_PARTIAL;
 			skb->csum_start = skb_headroom(skb) +
 					  skb_network_offset(skb) +