[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/drivers/net/bnx2.c b/drivers/net/bnx2.c
index ce3ed67..0f4f76f 100644
--- a/drivers/net/bnx2.c
+++ b/drivers/net/bnx2.c
@@ -6490,10 +6490,10 @@
memcpy(dev->perm_addr, bp->mac_addr, 6);
bp->name = board_info[ent->driver_data].name;
+ dev->features |= NETIF_F_IP_CSUM | NETIF_F_SG;
if (CHIP_NUM(bp) == CHIP_NUM_5709)
- dev->features |= NETIF_F_HW_CSUM | NETIF_F_SG;
- else
- dev->features |= NETIF_F_IP_CSUM | NETIF_F_SG;
+ dev->features |= NETIF_F_IPV6_CSUM;
+
#ifdef BCM_VLAN
dev->features |= NETIF_F_HW_VLAN_TX | NETIF_F_HW_VLAN_RX;
#endif
diff --git a/drivers/net/tg3.c b/drivers/net/tg3.c
index 2f31841..3a43426 100644
--- a/drivers/net/tg3.c
+++ b/drivers/net/tg3.c
@@ -11944,12 +11944,11 @@
* checksumming.
*/
if ((tp->tg3_flags & TG3_FLAG_BROKEN_CHECKSUMS) == 0) {
+ dev->features |= NETIF_F_IP_CSUM | NETIF_F_SG;
if (GET_ASIC_REV(tp->pci_chip_rev_id) == ASIC_REV_5755 ||
GET_ASIC_REV(tp->pci_chip_rev_id) == ASIC_REV_5787)
- dev->features |= NETIF_F_HW_CSUM;
- else
- dev->features |= NETIF_F_IP_CSUM;
- dev->features |= NETIF_F_SG;
+ dev->features |= NETIF_F_IPV6_CSUM;
+
tp->tg3_flags |= TG3_FLAG_RX_CHECKSUMS;
} else
tp->tg3_flags &= ~TG3_FLAG_RX_CHECKSUMS;
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index e7913ee..7a8f22f 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -314,9 +314,10 @@
/* Net device features */
unsigned long features;
#define NETIF_F_SG 1 /* Scatter/gather IO. */
-#define NETIF_F_IP_CSUM 2 /* Can checksum only TCP/UDP over IPv4. */
+#define NETIF_F_IP_CSUM 2 /* Can checksum TCP/UDP over IPv4. */
#define NETIF_F_NO_CSUM 4 /* Does not require checksum. F.e. loopack. */
#define NETIF_F_HW_CSUM 8 /* Can checksum all the packets. */
+#define NETIF_F_IPV6_CSUM 16 /* Can checksum TCP/UDP over IPV6 */
#define NETIF_F_HIGHDMA 32 /* Can DMA to high memory. */
#define NETIF_F_FRAGLIST 64 /* Scatter/gather IO. */
#define NETIF_F_HW_VLAN_TX 128 /* Transmit VLAN hw acceleration */
@@ -338,8 +339,11 @@
/* List of features with software fallbacks. */
#define NETIF_F_GSO_SOFTWARE (NETIF_F_TSO | NETIF_F_TSO_ECN | NETIF_F_TSO6)
+
#define NETIF_F_GEN_CSUM (NETIF_F_NO_CSUM | NETIF_F_HW_CSUM)
-#define NETIF_F_ALL_CSUM (NETIF_F_IP_CSUM | NETIF_F_GEN_CSUM)
+#define NETIF_F_V4_CSUM (NETIF_F_GEN_CSUM | NETIF_F_IP_CSUM)
+#define NETIF_F_V6_CSUM (NETIF_F_GEN_CSUM | NETIF_F_IPV6_CSUM)
+#define NETIF_F_ALL_CSUM (NETIF_F_V4_CSUM | NETIF_F_V6_CSUM)
struct net_device *next_sched;
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 &