Commit d96535a1 authored by Tom Herbert's avatar Tom Herbert Committed by David S. Miller
Browse files

net: Infrastructure for checksum unnecessary conversions 



For normal path, added skb_checksum_try_convert which is called
to attempt to convert CHECKSUM_UNNECESSARY to CHECKSUM_COMPLETE. The
primary condition to allow this is that ip_summed is CHECKSUM_NONE
and csum_valid is true, which will be the state after consuming
a CHECKSUM_UNNECESSARY.

For GRO path, added skb_gro_checksum_try_convert which is the GRO
analogue of skb_checksum_try_convert. The primary condition to allow
this is that NAPI_GRO_CB(skb)->csum_cnt == 0 and
NAPI_GRO_CB(skb)->csum_valid is set. This implies that we have consumed
all available CHECKSUM_UNNECESSARY checksums in the GRO path.

Signed-off-by: default avatarTom Herbert <therbert@google.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 5a212329

include/linux/netdevice.h

+20 −0
Original line number Diff line number Diff line
@@ -2233,6 +2233,26 @@ static inline void skb_gro_incr_csum_unnecessary(struct sk_buff *skb) 
#define skb_gro_checksum_simple_validate(skb)				\

	__skb_gro_checksum_validate(skb, 0, false, 0, null_compute_pseudo)



static inline bool __skb_gro_checksum_convert_check(struct sk_buff *skb)

{

	return (NAPI_GRO_CB(skb)->csum_cnt == 0 &&

		!NAPI_GRO_CB(skb)->csum_valid);

}



static inline void __skb_gro_checksum_convert(struct sk_buff *skb,

					      __sum16 check, __wsum pseudo)

{

	NAPI_GRO_CB(skb)->csum = ~pseudo;

	NAPI_GRO_CB(skb)->csum_valid = 1;

}



#define skb_gro_checksum_try_convert(skb, proto, check, compute_pseudo)	\

do {									\

	if (__skb_gro_checksum_convert_check(skb))			\

		__skb_gro_checksum_convert(skb, check,			\

					   compute_pseudo(skb, proto));	\

} while (0)



static inline int dev_hard_header(struct sk_buff *skb, struct net_device *dev,

				  unsigned short type,

				  const void *daddr, const void *saddr,

include/linux/skbuff.h

+20 −0
Original line number Diff line number Diff line
@@ -2942,6 +2942,26 @@ static inline __wsum null_compute_pseudo(struct sk_buff *skb, int proto) 
#define skb_checksum_simple_validate(skb)				\

	__skb_checksum_validate(skb, 0, true, false, 0, null_compute_pseudo)



static inline bool __skb_checksum_convert_check(struct sk_buff *skb)

{

	return (skb->ip_summed == CHECKSUM_NONE &&

		skb->csum_valid && !skb->csum_bad);

}



static inline void __skb_checksum_convert(struct sk_buff *skb,

					  __sum16 check, __wsum pseudo)

{

	skb->csum = ~pseudo;

	skb->ip_summed = CHECKSUM_COMPLETE;

}



#define skb_checksum_try_convert(skb, proto, check, compute_pseudo)	\

do {									\

	if (__skb_checksum_convert_check(skb))				\

		__skb_checksum_convert(skb, check,			\

				       compute_pseudo(skb, proto));	\

} while (0)



#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)

void nf_conntrack_destroy(struct nf_conntrack *nfct);

static inline void nf_conntrack_put(struct nf_conntrack *nfct)

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