vlan: Enable software emulation for vlan accleration.
Currently users of hardware vlan accleration need to know whether
the device supports it before generating packets. However, vlan
acceleration will soon be available in a more flexible manner so
knowing ahead of time becomes much more difficult. This adds
a software fallback path for vlan packets on devices without the
necessary offloading support, similar to other types of hardware
accleration.
Signed-off-by: Jesse Gross <jesse@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/netdevice.h b/include/linux/netdevice.h
index 880d565..2861565 100644
--- a/include/linux/netdevice.h
+++ b/include/linux/netdevice.h
@@ -2248,9 +2248,17 @@
static inline int netif_needs_gso(struct net_device *dev, struct sk_buff *skb)
{
- return skb_is_gso(skb) &&
- (!skb_gso_ok(skb, dev->features) ||
- unlikely(skb->ip_summed != CHECKSUM_PARTIAL));
+ if (skb_is_gso(skb)) {
+ int features = dev->features;
+
+ if (skb->protocol == htons(ETH_P_8021Q) || skb->vlan_tci)
+ features &= dev->vlan_features;
+
+ return (!skb_gso_ok(skb, features) ||
+ unlikely(skb->ip_summed != CHECKSUM_PARTIAL));
+ }
+
+ return 0;
}
static inline void netif_set_gso_max_size(struct net_device *dev,
diff --git a/net/core/dev.c b/net/core/dev.c
index 4c3ac53..1bfd96b 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -1694,7 +1694,12 @@
static bool dev_can_checksum(struct net_device *dev, struct sk_buff *skb)
{
- if (can_checksum_protocol(dev->features, skb->protocol))
+ int features = dev->features;
+
+ if (vlan_tx_tag_present(skb))
+ features &= dev->vlan_features;
+
+ if (can_checksum_protocol(features, skb->protocol))
return true;
if (skb->protocol == htons(ETH_P_8021Q)) {
@@ -1793,6 +1798,16 @@
__be16 type = skb->protocol;
int err;
+ if (type == htons(ETH_P_8021Q)) {
+ struct vlan_ethhdr *veh;
+
+ if (unlikely(!pskb_may_pull(skb, VLAN_ETH_HLEN)))
+ return ERR_PTR(-EINVAL);
+
+ veh = (struct vlan_ethhdr *)skb->data;
+ type = veh->h_vlan_encapsulated_proto;
+ }
+
skb_reset_mac_header(skb);
skb->mac_len = skb->network_header - skb->mac_header;
__skb_pull(skb, skb->mac_len);
@@ -1964,9 +1979,14 @@
static inline int skb_needs_linearize(struct sk_buff *skb,
struct net_device *dev)
{
+ int features = dev->features;
+
+ if (skb->protocol == htons(ETH_P_8021Q) || vlan_tx_tag_present(skb))
+ features &= dev->vlan_features;
+
return skb_is_nonlinear(skb) &&
- ((skb_has_frag_list(skb) && !(dev->features & NETIF_F_FRAGLIST)) ||
- (skb_shinfo(skb)->nr_frags && (!(dev->features & NETIF_F_SG) ||
+ ((skb_has_frag_list(skb) && !(features & NETIF_F_FRAGLIST)) ||
+ (skb_shinfo(skb)->nr_frags && (!(features & NETIF_F_SG) ||
illegal_highdma(dev, skb))));
}
@@ -1989,6 +2009,15 @@
skb_orphan_try(skb);
+ if (vlan_tx_tag_present(skb) &&
+ !(dev->features & NETIF_F_HW_VLAN_TX)) {
+ skb = __vlan_put_tag(skb, vlan_tx_tag_get(skb));
+ if (unlikely(!skb))
+ goto out;
+
+ skb->vlan_tci = 0;
+ }
+
if (netif_needs_gso(dev, skb)) {
if (unlikely(dev_gso_segment(skb)))
goto out_kfree_skb;
@@ -2050,6 +2079,7 @@
skb->destructor = DEV_GSO_CB(skb)->destructor;
out_kfree_skb:
kfree_skb(skb);
+out:
return rc;
}