[IPV6]: Avoid skb_copy/pskb_copy/skb_realloc_headroom on input

This patch replaces unnecessary uses of skb_copy by pskb_expand_head
on the IPv6 input path.

This allows us to remove the double pointers later.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Herbert Xu 2007-10-15 01:29:10 -07:00 committed by David S. Miller
parent f61944efdf
commit 65c8846660

View file

@ -234,22 +234,13 @@ static int ipv6_dest_hao(struct sk_buff **skbp, int optoff)
goto discard;
if (skb_cloned(skb)) {
struct sk_buff *skb2 = skb_copy(skb, GFP_ATOMIC);
struct inet6_skb_parm *opt2;
if (skb2 == NULL)
if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC))
goto discard;
opt2 = IP6CB(skb2);
memcpy(opt2, opt, sizeof(*opt2));
kfree_skb(skb);
/* update all variable using below by copied skbuff */
*skbp = skb = skb2;
hao = (struct ipv6_destopt_hao *)(skb_network_header(skb2) +
hao = (struct ipv6_destopt_hao *)(skb_network_header(skb) +
optoff);
ipv6h = ipv6_hdr(skb2);
ipv6h = ipv6_hdr(skb);
}
if (skb->ip_summed == CHECKSUM_COMPLETE)
@ -464,18 +455,14 @@ looped_back:
Do not damage packets queued somewhere.
*/
if (skb_cloned(skb)) {
struct sk_buff *skb2 = skb_copy(skb, GFP_ATOMIC);
/* the copy is a forwarded packet */
if (skb2 == NULL) {
if (pskb_expand_head(skb, 0, 0, GFP_ATOMIC)) {
IP6_INC_STATS_BH(ip6_dst_idev(skb->dst),
IPSTATS_MIB_OUTDISCARDS);
kfree_skb(skb);
return -1;
}
kfree_skb(skb);
*skbp = skb = skb2;
opt = IP6CB(skb2);
hdr = (struct ipv6_rt_hdr *)skb_transport_header(skb2);
hdr = (struct ipv6_rt_hdr *)skb_transport_header(skb);
}
if (skb->ip_summed == CHECKSUM_COMPLETE)