sch_choke: add choke_skb_cb

Better document choke skb->cb[] use, like we did in netem and sfb

This adds a compile time check to make sure we dont exhaust skb->cb[]
space.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
CC: Stephen Hemminger <shemminger@vyatta.com>
CC: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2011-02-24 17:45:41 +00:00 committed by David S. Miller
parent 250a65f782
commit 26f70e1202
1 changed files with 13 additions and 2 deletions

View File

@ -219,14 +219,25 @@ static bool choke_match_flow(struct sk_buff *skb1,
return *ports1 == *ports2;
}
struct choke_skb_cb {
u16 classid;
};
static inline struct choke_skb_cb *choke_skb_cb(const struct sk_buff *skb)
{
BUILD_BUG_ON(sizeof(skb->cb) <
sizeof(struct qdisc_skb_cb) + sizeof(struct choke_skb_cb));
return (struct choke_skb_cb *)qdisc_skb_cb(skb)->data;
}
static inline void choke_set_classid(struct sk_buff *skb, u16 classid)
{
*(unsigned int *)(qdisc_skb_cb(skb)->data) = classid;
choke_skb_cb(skb)->classid = classid;
}
static u16 choke_get_classid(const struct sk_buff *skb)
{
return *(unsigned int *)(qdisc_skb_cb(skb)->data);
return choke_skb_cb(skb)->classid;
}
/*