filter: constify sk_run_filter()

sk_run_filter() doesnt write on skb, change its prototype to reflect
this.

Fix two af_packet comments.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet
2010-12-06 20:50:09 +00:00
committed by David S. Miller
parent 38f49e8801
commit 62ab081213
4 changed files with 22 additions and 20 deletions

View File

@@ -517,7 +517,8 @@ out_free:
return err;
}
static inline unsigned int run_filter(struct sk_buff *skb, struct sock *sk,
static inline unsigned int run_filter(const struct sk_buff *skb,
const struct sock *sk,
unsigned int res)
{
struct sk_filter *filter;
@@ -532,15 +533,15 @@ static inline unsigned int run_filter(struct sk_buff *skb, struct sock *sk,
}
/*
This function makes lazy skb cloning in hope that most of packets
are discarded by BPF.
Note tricky part: we DO mangle shared skb! skb->data, skb->len
and skb->cb are mangled. It works because (and until) packets
falling here are owned by current CPU. Output packets are cloned
by dev_queue_xmit_nit(), input packets are processed by net_bh
sequencially, so that if we return skb to original state on exit,
we will not harm anyone.
* This function makes lazy skb cloning in hope that most of packets
* are discarded by BPF.
*
* Note tricky part: we DO mangle shared skb! skb->data, skb->len
* and skb->cb are mangled. It works because (and until) packets
* falling here are owned by current CPU. Output packets are cloned
* by dev_queue_xmit_nit(), input packets are processed by net_bh
* sequencially, so that if we return skb to original state on exit,
* we will not harm anyone.
*/
static int packet_rcv(struct sk_buff *skb, struct net_device *dev,
@@ -566,11 +567,11 @@ static int packet_rcv(struct sk_buff *skb, struct net_device *dev,
if (dev->header_ops) {
/* The device has an explicit notion of ll header,
exported to higher levels.
Otherwise, the device hides datails of it frame
structure, so that corresponding packet head
never delivered to user.
* exported to higher levels.
*
* Otherwise, the device hides details of its frame
* structure, so that corresponding packet head is
* never delivered to user.
*/
if (sk->sk_type != SOCK_DGRAM)
skb_push(skb, skb->data - skb_mac_header(skb));