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#include <linux/netdevice.h>
#include <linux/if_vlan.h>
#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,38)
#ifndef HAVE_CAN_CHECKSUM_PROTOCOL
static bool can_checksum_protocol(netdev_features_t features, __be16 protocol)
{
return ((features & NETIF_F_GEN_CSUM) ||
((features & NETIF_F_V4_CSUM) &&
protocol == htons(ETH_P_IP)) ||
((features & NETIF_F_V6_CSUM) &&
protocol == htons(ETH_P_IPV6)) ||
((features & NETIF_F_FCOE_CRC) &&
protocol == htons(ETH_P_FCOE)));
}
#endif
static inline int illegal_highdma(struct net_device *dev, struct sk_buff *skb)
{
#ifdef CONFIG_HIGHMEM
int i;
if (dev->features & NETIF_F_HIGHDMA)
return 0;
for (i = 0; i < skb_shinfo(skb)->nr_frags; i++)
if (PageHighMem(skb_shinfo(skb)->frags[i].page))
return 1;
#endif
return 0;
}
static netdev_features_t harmonize_features(struct sk_buff *skb,
__be16 protocol,
netdev_features_t features)
{
if (!can_checksum_protocol(features, protocol)) {
features &= ~NETIF_F_ALL_CSUM;
features &= ~NETIF_F_SG;
} else if (illegal_highdma(skb->dev, skb)) {
features &= ~NETIF_F_SG;
}
return features;
}
netdev_features_t rpl_netif_skb_features(struct sk_buff *skb)
{
unsigned long vlan_features = skb->dev->vlan_features;
__be16 protocol = skb->protocol;
netdev_features_t features = skb->dev->features;
if (protocol == htons(ETH_P_8021Q)) {
struct vlan_ethhdr *veh = (struct vlan_ethhdr *)skb->data;
protocol = veh->h_vlan_encapsulated_proto;
} else if (!vlan_tx_tag_present(skb)) {
return harmonize_features(skb, protocol, features);
}
features &= (vlan_features | NETIF_F_HW_VLAN_TX);
if (protocol != htons(ETH_P_8021Q)) {
return harmonize_features(skb, protocol, features);
} else {
features &= NETIF_F_SG | NETIF_F_HIGHDMA | NETIF_F_FRAGLIST |
NETIF_F_GEN_CSUM | NETIF_F_HW_VLAN_TX;
return harmonize_features(skb, protocol, features);
}
}
struct sk_buff *rpl_skb_gso_segment(struct sk_buff *skb,
netdev_features_t features)
{
int vlan_depth = ETH_HLEN;
__be16 type = skb->protocol;
__be16 skb_proto;
struct sk_buff *skb_gso;
while (type == htons(ETH_P_8021Q)) {
struct vlan_hdr *vh;
if (unlikely(!pskb_may_pull(skb, vlan_depth + VLAN_HLEN)))
return ERR_PTR(-EINVAL);
vh = (struct vlan_hdr *)(skb->data + vlan_depth);
type = vh->h_vlan_encapsulated_proto;
vlan_depth += VLAN_HLEN;
}
/* this hack needed to get regular skb_gso_segment() */
#undef skb_gso_segment
skb_proto = skb->protocol;
skb->protocol = type;
skb_gso = skb_gso_segment(skb, features);
skb->protocol = skb_proto;
return skb_gso;
}
#endif /* kernel version < 2.6.38 */
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