kernel-fxtec-pro1x/net/8021q/vlan_core.c
John Fastabend 597a264b1a net: deliver skbs on inactive slaves to exact matches
Currently, the accelerated receive path for VLAN's will
drop packets if the real device is an inactive slave and
is not one of the special pkts tested for in
skb_bond_should_drop().  This behavior is different then
the non-accelerated path and for pkts over a bonded vlan.

For example,

vlanx -> bond0 -> ethx

will be dropped in the vlan path and not delivered to any
packet handlers at all.  However,

bond0 -> vlanx -> ethx

and

bond0 -> ethx

will be delivered to handlers that match the exact dev,
because the VLAN path checks the real_dev which is not a
slave and netif_recv_skb() doesn't drop frames but only
delivers them to exact matches.

This patch adds a sk_buff flag which is used for tagging
skbs that would previously been dropped and allows the
skb to continue to skb_netif_recv().  Here we add
logic to check for the deliver_no_wcard flag and if it
is set only deliver to handlers that match exactly.  This
makes both paths above consistent and gives pkt handlers
a way to identify skbs that come from inactive slaves.
Without this patch in some configurations skbs will be
delivered to handlers with exact matches and in others
be dropped out right in the vlan path.

I have tested the following 4 configurations in failover modes
and load balancing modes.

# bond0 -> ethx

# vlanx -> bond0 -> ethx

# bond0 -> vlanx -> ethx

# bond0 -> ethx
            |
  vlanx -> --

Signed-off-by: John Fastabend <john.r.fastabend@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2010-06-10 22:23:34 -07:00

139 lines
3.4 KiB
C

#include <linux/skbuff.h>
#include <linux/netdevice.h>
#include <linux/if_vlan.h>
#include <linux/netpoll.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 (netpoll_rx(skb))
return NET_RX_DROP;
if (skb_bond_should_drop(skb, ACCESS_ONCE(skb->dev->master)))
skb->deliver_no_wcard = 1;
skb->skb_iif = skb->dev->ifindex;
__vlan_hwaccel_put_tag(skb, 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 vlan_rx_stats *rx_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;
rx_stats = per_cpu_ptr(vlan_dev_info(dev)->vlan_rx_stats,
smp_processor_id());
rx_stats->rx_packets++;
rx_stats->rx_bytes += skb->len;
switch (skb->pkt_type) {
case PACKET_BROADCAST:
break;
case PACKET_MULTICAST:
rx_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 gro_result_t
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, ACCESS_ONCE(skb->dev->master)))
skb->deliver_no_wcard = 1;
skb->skb_iif = skb->dev->ifindex;
__vlan_hwaccel_put_tag(skb, 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 && !compare_ether_header(
skb_mac_header(p), skb_gro_mac_header(skb));
NAPI_GRO_CB(p)->flush = 0;
}
return dev_gro_receive(napi, skb);
drop:
return GRO_DROP;
}
gro_result_t vlan_gro_receive(struct napi_struct *napi, struct vlan_group *grp,
unsigned int vlan_tci, struct sk_buff *skb)
{
if (netpoll_rx_on(skb))
return vlan_hwaccel_receive_skb(skb, grp, vlan_tci)
? GRO_DROP : GRO_NORMAL;
skb_gro_reset_offset(skb);
return napi_skb_finish(vlan_gro_common(napi, grp, vlan_tci, skb), skb);
}
EXPORT_SYMBOL(vlan_gro_receive);
gro_result_t vlan_gro_frags(struct napi_struct *napi, struct vlan_group *grp,
unsigned int vlan_tci)
{
struct sk_buff *skb = napi_frags_skb(napi);
if (!skb)
return GRO_DROP;
if (netpoll_rx_on(skb)) {
skb->protocol = eth_type_trans(skb, skb->dev);
return vlan_hwaccel_receive_skb(skb, grp, vlan_tci)
? GRO_DROP : GRO_NORMAL;
}
return napi_frags_finish(napi, skb,
vlan_gro_common(napi, grp, vlan_tci, skb));
}
EXPORT_SYMBOL(vlan_gro_frags);