[NET]: IPV6 checksum offloading in network devices
The existing model for checksum offload does not correctly handle
devices that can offload IPV4 and IPV6 only. The NETIF_F_HW_CSUM flag
implies device can do any arbitrary protocol.
This patch:
* adds NETIF_F_IPV6_CSUM for those devices
* fixes bnx2 and tg3 devices that need it
* add NETIF_F_IPV6_CSUM to ipv6 output (incl GSO)
* fixes assumptions about NETIF_F_ALL_CSUM in nat
* adjusts bridge union of checksumming computation
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/bridge/br_if.c b/net/bridge/br_if.c
index 849deaf..7b4ce91 100644
--- a/net/bridge/br_if.c
+++ b/net/bridge/br_if.c
@@ -368,10 +368,18 @@
list_for_each_entry(p, &br->port_list, list) {
unsigned long feature = p->dev->features;
+ /* if device needs checksumming, downgrade to hw checksumming */
if (checksum & NETIF_F_NO_CSUM && !(feature & NETIF_F_NO_CSUM))
checksum ^= NETIF_F_NO_CSUM | NETIF_F_HW_CSUM;
+
+ /* if device can't do all checksum, downgrade to ipv4/ipv6 */
if (checksum & NETIF_F_HW_CSUM && !(feature & NETIF_F_HW_CSUM))
- checksum ^= NETIF_F_HW_CSUM | NETIF_F_IP_CSUM;
+ checksum ^= NETIF_F_HW_CSUM
+ | NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM;
+
+ if (checksum & NETIF_F_IPV6_CSUM && !(feature & NETIF_F_IPV6_CSUM))
+ checksum &= ~NETIF_F_IPV6_CSUM;
+
if (!(feature & NETIF_F_IP_CSUM))
checksum = 0;
diff --git a/net/core/dev.c b/net/core/dev.c
index ee051bb..a0a46e7 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -1509,9 +1509,11 @@
skb_set_transport_header(skb, skb->csum_start -
skb_headroom(skb));
- if (!(dev->features & NETIF_F_GEN_CSUM) &&
- (!(dev->features & NETIF_F_IP_CSUM) ||
- skb->protocol != htons(ETH_P_IP)))
+ if (!(dev->features & NETIF_F_GEN_CSUM)
+ || ((dev->features & NETIF_F_IP_CSUM)
+ && skb->protocol == htons(ETH_P_IP))
+ || ((dev->features & NETIF_F_IPV6_CSUM)
+ && skb->protocol == htons(ETH_P_IPV6)))
if (skb_checksum_help(skb))
goto out_kfree_skb;
}
@@ -3107,6 +3109,22 @@
}
}
+ /* Fix illegal checksum combinations */
+ if ((dev->features & NETIF_F_HW_CSUM) &&
+ (dev->features & (NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
+ printk(KERN_NOTICE "%s: mixed HW and IP checksum settings.\n",
+ dev->name);
+ dev->features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM);
+ }
+
+ if ((dev->features & NETIF_F_NO_CSUM) &&
+ (dev->features & (NETIF_F_HW_CSUM|NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM))) {
+ printk(KERN_NOTICE "%s: mixed no checksumming and other settings.\n",
+ dev->name);
+ dev->features &= ~(NETIF_F_IP_CSUM|NETIF_F_IPV6_CSUM|NETIF_F_HW_CSUM);
+ }
+
+
/* Fix illegal SG+CSUM combinations. */
if ((dev->features & NETIF_F_SG) &&
!(dev->features & NETIF_F_ALL_CSUM)) {
diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index 041fba3..06c08e5 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -1170,6 +1170,9 @@
int ihl;
int id;
+ if (!(features & NETIF_F_V4_CSUM))
+ features &= ~NETIF_F_SG;
+
if (unlikely(skb_shinfo(skb)->gso_type &
~(SKB_GSO_TCPV4 |
SKB_GSO_UDP |
diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index 34ea454..a7dd343 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -837,7 +837,7 @@
*/
if (transhdrlen &&
length + fragheaderlen <= mtu &&
- rt->u.dst.dev->features & NETIF_F_ALL_CSUM &&
+ rt->u.dst.dev->features & NETIF_F_V4_CSUM &&
!exthdrlen)
csummode = CHECKSUM_PARTIAL;
diff --git a/net/ipv4/netfilter/nf_nat_helper.c b/net/ipv4/netfilter/nf_nat_helper.c
index 15b6e5c..b1aa598 100644
--- a/net/ipv4/netfilter/nf_nat_helper.c
+++ b/net/ipv4/netfilter/nf_nat_helper.c
@@ -178,7 +178,7 @@
datalen = (*pskb)->len - iph->ihl*4;
if ((*pskb)->ip_summed != CHECKSUM_PARTIAL) {
if (!(rt->rt_flags & RTCF_LOCAL) &&
- (*pskb)->dev->features & NETIF_F_ALL_CSUM) {
+ (*pskb)->dev->features & NETIF_F_V4_CSUM) {
(*pskb)->ip_summed = CHECKSUM_PARTIAL;
(*pskb)->csum_start = skb_headroom(*pskb) +
skb_network_offset(*pskb) +
@@ -265,7 +265,7 @@
if ((*pskb)->ip_summed != CHECKSUM_PARTIAL) {
if (!(rt->rt_flags & RTCF_LOCAL) &&
- (*pskb)->dev->features & NETIF_F_ALL_CSUM) {
+ (*pskb)->dev->features & NETIF_F_V4_CSUM) {
(*pskb)->ip_summed = CHECKSUM_PARTIAL;
(*pskb)->csum_start = skb_headroom(*pskb) +
skb_network_offset(*pskb) +
diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c
index b636c38..1c35066 100644
--- a/net/ipv6/ipv6_sockglue.c
+++ b/net/ipv6/ipv6_sockglue.c
@@ -123,7 +123,7 @@
struct ipv6hdr *ipv6h;
struct inet6_protocol *ops;
- if (!(features & NETIF_F_HW_CSUM))
+ if (!(features & NETIF_F_V6_CSUM))
features &= ~NETIF_F_SG;
if (unlikely(skb_shinfo(skb)->gso_type &