aha/net/8021q/vlan_core.c
Herbert Xu 86911732d3 gro: Avoid copying headers of unmerged packets
Unfortunately simplicity isn't always the best.  The fraginfo
interface turned out to be suboptimal.  The problem was quite
obvious.  For every packet, we have to copy the headers from
the frags structure into skb->head, even though for 99% of the
packets this part is immediately thrown away after the merge.

LRO didn't have this problem because it directly read the headers
from the frags structure.

This patch attempts to address this by creating an interface
that allows GRO to access the headers in the first frag without
having to copy it.  Because all drivers that use frags place the
headers in the first frag this optimisation should be enough.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
2009-01-29 16:33:03 -08:00

118 lines
2.7 KiB
C

#include <linux/skbuff.h>
#include <linux/netdevice.h>
#include <linux/if_vlan.h>
#include "vlan.h"
/* VLAN rx hw acceleration helper. This acts like netif_{rx,receive_skb}(). */
int __vlan_hwaccel_rx(struct sk_buff *skb, struct vlan_group *grp,
u16 vlan_tci, int polling)
{
if (skb_bond_should_drop(skb))
goto drop;
skb->vlan_tci = vlan_tci;
skb->dev = vlan_group_get_device(grp, vlan_tci & VLAN_VID_MASK);
if (!skb->dev)
goto drop;
return (polling ? netif_receive_skb(skb) : netif_rx(skb));
drop:
dev_kfree_skb_any(skb);
return NET_RX_DROP;
}
EXPORT_SYMBOL(__vlan_hwaccel_rx);
int vlan_hwaccel_do_receive(struct sk_buff *skb)
{
struct net_device *dev = skb->dev;
struct net_device_stats *stats;
skb->dev = vlan_dev_info(dev)->real_dev;
netif_nit_deliver(skb);
skb->dev = dev;
skb->priority = vlan_get_ingress_priority(dev, skb->vlan_tci);
skb->vlan_tci = 0;
stats = &dev->stats;
stats->rx_packets++;
stats->rx_bytes += skb->len;
switch (skb->pkt_type) {
case PACKET_BROADCAST:
break;
case PACKET_MULTICAST:
stats->multicast++;
break;
case PACKET_OTHERHOST:
/* Our lower layer thinks this is not local, let's make sure.
* This allows the VLAN to have a different MAC than the
* underlying device, and still route correctly. */
if (!compare_ether_addr(eth_hdr(skb)->h_dest,
dev->dev_addr))
skb->pkt_type = PACKET_HOST;
break;
};
return 0;
}
struct net_device *vlan_dev_real_dev(const struct net_device *dev)
{
return vlan_dev_info(dev)->real_dev;
}
EXPORT_SYMBOL(vlan_dev_real_dev);
u16 vlan_dev_vlan_id(const struct net_device *dev)
{
return vlan_dev_info(dev)->vlan_id;
}
EXPORT_SYMBOL(vlan_dev_vlan_id);
static int vlan_gro_common(struct napi_struct *napi, struct vlan_group *grp,
unsigned int vlan_tci, struct sk_buff *skb)
{
struct sk_buff *p;
if (skb_bond_should_drop(skb))
goto drop;
skb->vlan_tci = vlan_tci;
skb->dev = vlan_group_get_device(grp, vlan_tci & VLAN_VID_MASK);
if (!skb->dev)
goto drop;
for (p = napi->gro_list; p; p = p->next) {
NAPI_GRO_CB(p)->same_flow = p->dev == skb->dev;
NAPI_GRO_CB(p)->flush = 0;
}
return dev_gro_receive(napi, skb);
drop:
return 2;
}
int vlan_gro_receive(struct napi_struct *napi, struct vlan_group *grp,
unsigned int vlan_tci, struct sk_buff *skb)
{
skb_gro_reset_offset(skb);
return napi_skb_finish(vlan_gro_common(napi, grp, vlan_tci, skb), skb);
}
EXPORT_SYMBOL(vlan_gro_receive);
int vlan_gro_frags(struct napi_struct *napi, struct vlan_group *grp,
unsigned int vlan_tci, struct napi_gro_fraginfo *info)
{
struct sk_buff *skb = napi_fraginfo_skb(napi, info);
if (!skb)
return NET_RX_DROP;
return napi_frags_finish(napi, skb,
vlan_gro_common(napi, grp, vlan_tci, skb));
}
EXPORT_SYMBOL(vlan_gro_frags);