net: add skb_get_dsfield() helper

skb_get_dsfield(skb) gets dsfield from skb, or -1
if an error was found.

This is basically a wrapper around ipv4_get_dsfield()
and ipv6_get_dsfield().

Used by following patch for fq_codel.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Cc: Ingemar Johansson S <ingemar.s.johansson@ericsson.com>
Cc: Tom Henderson <tomh@tomh.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2021-10-14 10:59:17 -07:00 committed by David S. Miller
parent 19757cebf0
commit 70e939ddea

View File

@ -188,6 +188,23 @@ static inline int INET_ECN_set_ce(struct sk_buff *skb)
return 0;
}
static inline int skb_get_dsfield(struct sk_buff *skb)
{
switch (skb_protocol(skb, true)) {
case cpu_to_be16(ETH_P_IP):
if (!pskb_network_may_pull(skb, sizeof(struct iphdr)))
break;
return ipv4_get_dsfield(ip_hdr(skb));
case cpu_to_be16(ETH_P_IPV6):
if (!pskb_network_may_pull(skb, sizeof(struct ipv6hdr)))
break;
return ipv6_get_dsfield(ipv6_hdr(skb));
}
return -1;
}
static inline int INET_ECN_set_ect1(struct sk_buff *skb)
{
switch (skb_protocol(skb, true)) {