Merge refs/heads/ieee80211-wifi from master.kernel.org:/pub/scm/linux/kernel/git...

[linux-2.6] / net / ipv4 / ip_input.c

diff --git a/net/ipv4/ip_input.c b/net/ipv4/ip_input.c
index 322b082ede1ecaa58545ea34017d4873e9524c96..473d0f2b2e0d6b5a4252f7c825ea870a2afc2c91 100644 (file)
--- a/net/ipv4/ip_input.c
+++ b/net/ipv4/ip_input.c
@@ -150,7 +150,7 @@
  *     SNMP management statistics
  */
 
-DEFINE_SNMP_STAT(struct ipstats_mib, ip_statistics);
+DEFINE_SNMP_STAT(struct ipstats_mib, ip_statistics) __read_mostly;
 
 /*
  *     Process Router Attention IP option
@@ -279,18 +279,70 @@ int ip_local_deliver(struct sk_buff *skb)
                       ip_local_deliver_finish);
 }
 
-static inline int ip_rcv_finish(struct sk_buff *skb)
+static inline int ip_rcv_options(struct sk_buff *skb)
 {
+       struct ip_options *opt;
+       struct iphdr *iph;
        struct net_device *dev = skb->dev;
+
+       /* It looks as overkill, because not all
+          IP options require packet mangling.
+          But it is the easiest for now, especially taking
+          into account that combination of IP options
+          and running sniffer is extremely rare condition.
+                                             --ANK (980813)
+       */
+       if (skb_cow(skb, skb_headroom(skb))) {
+               IP_INC_STATS_BH(IPSTATS_MIB_INDISCARDS);
+               goto drop;
+       }
+
+       iph = skb->nh.iph;
+
+       if (ip_options_compile(NULL, skb)) {
+               IP_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS);
+               goto drop;
+       }
+
+       opt = &(IPCB(skb)->opt);
+       if (unlikely(opt->srr)) {
+               struct in_device *in_dev = in_dev_get(dev);
+               if (in_dev) {
+                       if (!IN_DEV_SOURCE_ROUTE(in_dev)) {
+                               if (IN_DEV_LOG_MARTIANS(in_dev) &&
+                                   net_ratelimit())
+                                       printk(KERN_INFO "source route option "
+                                              "%u.%u.%u.%u -> %u.%u.%u.%u\n",
+                                              NIPQUAD(iph->saddr),
+                                              NIPQUAD(iph->daddr));
+                               in_dev_put(in_dev);
+                               goto drop;
+                       }
+
+                       in_dev_put(in_dev);
+               }
+
+               if (ip_options_rcv_srr(skb))
+                       goto drop;
+       }
+
+       return 0;
+drop:
+       return -1;
+}
+
+static inline int ip_rcv_finish(struct sk_buff *skb)
+{
        struct iphdr *iph = skb->nh.iph;
-       int err;
 
        /*
         *      Initialise the virtual path cache for the packet. It describes
         *      how the packet travels inside Linux networking.
         */ 
-       if (skb->dst == NULL) {
-               if ((err = ip_route_input(skb, iph->daddr, iph->saddr, iph->tos, dev))) {
+       if (likely(skb->dst == NULL)) {
+               int err = ip_route_input(skb, iph->daddr, iph->saddr, iph->tos,
+                                        skb->dev);
+               if (unlikely(err)) {
                        if (err == -EHOSTUNREACH)
                                IP_INC_STATS_BH(IPSTATS_MIB_INADDRERRORS);
                        goto drop; 
@@ -298,7 +350,7 @@ static inline int ip_rcv_finish(struct sk_buff *skb)
        }
 
 #ifdef CONFIG_NET_CLS_ROUTE
-       if (skb->dst->tclassid) {
+       if (unlikely(skb->dst->tclassid)) {
                struct ip_rt_acct *st = ip_rt_acct + 256*smp_processor_id();
                u32 idx = skb->dst->tclassid;
                st[idx&0xFF].o_packets++;
@@ -308,48 +360,11 @@ static inline int ip_rcv_finish(struct sk_buff *skb)
        }
 #endif
 
-       if (iph->ihl > 5) {
-               struct ip_options *opt;
-
-               /* It looks as overkill, because not all
-                  IP options require packet mangling.
-                  But it is the easiest for now, especially taking
-                  into account that combination of IP options
-                  and running sniffer is extremely rare condition.
-                                                     --ANK (980813)
-               */
-
-               if (skb_cow(skb, skb_headroom(skb))) {
-                       IP_INC_STATS_BH(IPSTATS_MIB_INDISCARDS);
-                       goto drop;
-               }
-               iph = skb->nh.iph;
-
-               if (ip_options_compile(NULL, skb))
-                       goto inhdr_error;
-
-               opt = &(IPCB(skb)->opt);
-               if (opt->srr) {
-                       struct in_device *in_dev = in_dev_get(dev);
-                       if (in_dev) {
-                               if (!IN_DEV_SOURCE_ROUTE(in_dev)) {
-                                       if (IN_DEV_LOG_MARTIANS(in_dev) && net_ratelimit())
-                                               printk(KERN_INFO "source route option %u.%u.%u.%u -> %u.%u.%u.%u\n",
-                                                      NIPQUAD(iph->saddr), NIPQUAD(iph->daddr));
-                                       in_dev_put(in_dev);
-                                       goto drop;
-                               }
-                               in_dev_put(in_dev);
-                       }
-                       if (ip_options_rcv_srr(skb))
-                               goto drop;
-               }
-       }
+       if (iph->ihl > 5 && ip_rcv_options(skb))
+               goto drop;
 
        return dst_input(skb);
 
-inhdr_error:
-       IP_INC_STATS_BH(IPSTATS_MIB_INHDRERRORS);
 drop:
         kfree_skb(skb);
         return NET_RX_DROP;
@@ -400,7 +415,7 @@ int ip_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt,
 
        iph = skb->nh.iph;
 
-       if (ip_fast_csum((u8 *)iph, iph->ihl) != 0)
+       if (unlikely(ip_fast_csum((u8 *)iph, iph->ihl)))
                goto inhdr_error;
 
        len = ntohs(iph->tot_len);
@@ -427,5 +442,4 @@ out:
         return NET_RX_DROP;
 }
 
-EXPORT_SYMBOL(ip_rcv);
 EXPORT_SYMBOL(ip_statistics);