From 9bcfcaf5e9cc887eb39236e43bdbe4b4b2572229 Mon Sep 17 00:00:00 2001
From: Stephen Hemminger <shemminger@osdl.org>
Date: Tue, 29 Aug 2006 17:48:57 -0700
Subject: [PATCH] [NETFILTER] bridge: simplify nf_bridge_pad
Do some simple optimization on the nf_bridge_pad() function
and don't use magic constants. Eliminate a double call and
the #ifdef'd code for CONFIG_BRIDGE_NETFILTER.
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
include/linux/netfilter_bridge.h | 16 +++++-----------
net/ipv4/ip_output.c | 15 +++++++--------
2 files changed, 12 insertions(+), 19 deletions(-)
diff --git a/include/linux/netfilter_bridge.h b/include/linux/netfilter_bridge.h
index 274fe4b33155..9a4dd11af86e 100644
--- a/include/linux/netfilter_bridge.h
+++ b/include/linux/netfilter_bridge.h
@@ -5,9 +5,8 @@
*/
#include <linux/netfilter.h>
-#if defined(__KERNEL__) && defined(CONFIG_BRIDGE_NETFILTER)
#include <linux/if_ether.h>
-#endif
+#include <linux/if_vlan.h>
/* Bridge Hooks */
/* After promisc drops, checksum checks. */
@@ -57,16 +56,10 @@ static inline int nf_bridge_maybe_copy_header(struct sk_buff *skb)
/* This is called by the IP fragmenting code and it ensures there is
* enough room for the encapsulating header (if there is one). */
-static inline
-int nf_bridge_pad(struct sk_buff *skb)
+static inline int nf_bridge_pad(const struct sk_buff *skb)
{
- if (skb->protocol == __constant_htons(ETH_P_IP))
- return 0;
- if (skb->nf_bridge) {
- if (skb->protocol == __constant_htons(ETH_P_8021Q))
- return 4;
- }
- return 0;
+ return (skb->nf_bridge && skb->protocol == htons(ETH_P_8021Q))
+ ? VLAN_HLEN : 0;
}
struct bridge_skb_cb {
@@ -78,6 +71,7 @@ struct bridge_skb_cb {
extern int brnf_deferred_hooks;
#else
#define nf_bridge_maybe_copy_header(skb) (0)
+#define nf_bridge_pad(skb) (0)
#endif /* CONFIG_BRIDGE_NETFILTER */
#endif /* __KERNEL__ */
diff --git a/net/ipv4/ip_output.c b/net/ipv4/ip_output.c
index 81b2795a4c20..97aee76fb746 100644
--- a/net/ipv4/ip_output.c
+++ b/net/ipv4/ip_output.c
@@ -426,7 +426,7 @@ int ip_fragment(struct sk_buff *skb, int (*output)(struct sk_buff*))
int ptr;
struct net_device *dev;
struct sk_buff *skb2;
- unsigned int mtu, hlen, left, len, ll_rs;
+ unsigned int mtu, hlen, left, len, ll_rs, pad;
int offset;
__be16 not_last_frag;
struct rtable *rt = (struct rtable*)skb->dst;
@@ -556,14 +556,13 @@ slow_path:
left = skb->len - hlen; /* Space per frame */
ptr = raw + hlen; /* Where to start from */
-#ifdef CONFIG_BRIDGE_NETFILTER
/* for bridged IP traffic encapsulated inside f.e. a vlan header,
- * we need to make room for the encapsulating header */
- ll_rs = LL_RESERVED_SPACE_EXTRA(rt->u.dst.dev, nf_bridge_pad(skb));
- mtu -= nf_bridge_pad(skb);
-#else
- ll_rs = LL_RESERVED_SPACE(rt->u.dst.dev);
-#endif
+ * we need to make room for the encapsulating header
+ */
+ pad = nf_bridge_pad(skb);
+ ll_rs = LL_RESERVED_SPACE_EXTRA(rt->u.dst.dev, pad);
+ mtu -= pad;
+
/*
* Fragment the datagram.
*/
--
2.20.1