net: add skb_pop_rcv_encapsulation

This function is used by UDP encapsulation protocols in RX when
crossing encapsulation boundary. If ip_summed is set to
CHECKSUM_UNNECESSARY and encapsulation is not set, change to
CHECKSUM_NONE since the checksum has not been validated within the
encapsulation. Clears csum_valid by the same rationale.

Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Tom Herbert 2014-06-14 23:24:28 -07:00 committed by David S. Miller
parent bbdff225ed
commit e5eb4e30a5
1 changed files with 12 additions and 0 deletions

View File

@ -1854,6 +1854,18 @@ static inline int pskb_network_may_pull(struct sk_buff *skb, unsigned int len)
return pskb_may_pull(skb, skb_network_offset(skb) + len);
}
static inline void skb_pop_rcv_encapsulation(struct sk_buff *skb)
{
/* Only continue with checksum unnecessary if device indicated
* it is valid across encapsulation (skb->encapsulation was set).
*/
if (skb->ip_summed == CHECKSUM_UNNECESSARY && !skb->encapsulation)
skb->ip_summed = CHECKSUM_NONE;
skb->encapsulation = 0;
skb->csum_valid = 0;
}
/*
* CPUs often take a performance hit when accessing unaligned memory
* locations. The actual performance hit varies, it can be small if the