diff options
| author | Jesse Gross <jesse@nicira.com> | 2010-10-29 12:14:53 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2010-11-15 09:22:52 -0800 |
| commit | e1e78db628b33c657944865e3bca01ee59cc5b80 (patch) | |
| tree | 98649d2224fbd76f9783905be498c5b70a63f50a /net/core/dev.c | |
| parent | 410989f65151557701ce86875b141e694281dd6c (diff) | |
| download | lwn-e1e78db628b33c657944865e3bca01ee59cc5b80.tar.gz lwn-e1e78db628b33c657944865e3bca01ee59cc5b80.zip | |
offloading: Make scatter/gather more tolerant of vlans.
When checking if it is necessary to linearize a packet, we currently
use vlan_features if the packet contains either an in-band or out-
of-band vlan tag. However, in-band tags aren't special in any way
for scatter/gather since they are part of the packet buffer and are
simply more data to DMA. Therefore, only use vlan_features for out-
of-band tags, which could potentially have some interaction with
scatter/gather.
Signed-off-by: Jesse Gross <jesse@nicira.com>
CC: Ben Hutchings <bhutchings@solarflare.com>
Reviewed-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/core/dev.c')
| -rw-r--r-- | net/core/dev.c | 19 |
1 files changed, 12 insertions, 7 deletions
diff --git a/net/core/dev.c b/net/core/dev.c index 5968c822c999..0b403d503311 100644 --- a/net/core/dev.c +++ b/net/core/dev.c @@ -1976,15 +1976,20 @@ static inline void skb_orphan_try(struct sk_buff *skb) static inline int skb_needs_linearize(struct sk_buff *skb, struct net_device *dev) { - int features = dev->features; + if (skb_is_nonlinear(skb)) { + int features = dev->features; - if (skb->protocol == htons(ETH_P_8021Q) || vlan_tx_tag_present(skb)) - features &= dev->vlan_features; + if (vlan_tx_tag_present(skb)) + features &= dev->vlan_features; - return skb_is_nonlinear(skb) && - ((skb_has_frag_list(skb) && !(features & NETIF_F_FRAGLIST)) || - (skb_shinfo(skb)->nr_frags && (!(features & NETIF_F_SG) || - illegal_highdma(dev, skb)))); + return (skb_has_frag_list(skb) && + !(features & NETIF_F_FRAGLIST)) || + (skb_shinfo(skb)->nr_frags && + (!(features & NETIF_F_SG) || + illegal_highdma(dev, skb))); + } + + return 0; } int dev_hard_start_xmit(struct sk_buff *skb, struct net_device *dev, |