net: Allow GRO to use and set levels of checksum unnecessary

Allow GRO path to "consume" checksums provided in CHECKSUM_UNNECESSARY
and to report new checksums verfied for use in fallback to normal
path.

Change GRO checksum path to track csum_level using a csum_cnt field
in NAPI_GRO_CB. On GRO initialization, if ip_summed is
CHECKSUM_UNNECESSARY set NAPI_GRO_CB(skb)->csum_cnt to
skb->csum_level + 1. For each checksum verified, decrement
NAPI_GRO_CB(skb)->csum_cnt while its greater than zero. If a checksum
is verfied and NAPI_GRO_CB(skb)->csum_cnt == 0, we have verified a
deeper checksum than originally indicated in skbuf so increment
csum_level (or initialize to CHECKSUM_UNNECESSARY if ip_summed is
CHECKSUM_NONE or CHECKSUM_COMPLETE).

Signed-off-by: Tom Herbert <therbert@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Tom Herbert
2014-08-27 21:26:56 -07:00
committed by David S. Miller
parent 77cffe23c1
commit 662880f442
4 changed files with 33 additions and 29 deletions

View File

@@ -3962,13 +3962,6 @@ static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff
gro_list_prepare(napi, skb);
if (skb->ip_summed == CHECKSUM_COMPLETE) {
NAPI_GRO_CB(skb)->csum = skb->csum;
NAPI_GRO_CB(skb)->csum_valid = 1;
} else {
NAPI_GRO_CB(skb)->csum_valid = 0;
}
rcu_read_lock();
list_for_each_entry_rcu(ptype, head, list) {
if (ptype->type != type || !ptype->callbacks.gro_receive)
@@ -3980,7 +3973,22 @@ static enum gro_result dev_gro_receive(struct napi_struct *napi, struct sk_buff
NAPI_GRO_CB(skb)->flush = 0;
NAPI_GRO_CB(skb)->free = 0;
NAPI_GRO_CB(skb)->udp_mark = 0;
NAPI_GRO_CB(skb)->encapsulation = 0;
/* Setup for GRO checksum validation */
switch (skb->ip_summed) {
case CHECKSUM_COMPLETE:
NAPI_GRO_CB(skb)->csum = skb->csum;
NAPI_GRO_CB(skb)->csum_valid = 1;
NAPI_GRO_CB(skb)->csum_cnt = 0;
break;
case CHECKSUM_UNNECESSARY:
NAPI_GRO_CB(skb)->csum_cnt = skb->csum_level + 1;
NAPI_GRO_CB(skb)->csum_valid = 0;
break;
default:
NAPI_GRO_CB(skb)->csum_cnt = 0;
NAPI_GRO_CB(skb)->csum_valid = 0;
}
pp = ptype->callbacks.gro_receive(&napi->gro_list, skb);
break;