flow_dissector: use a 64bit load/store

[karo-tx-linux.git] / net / core / flow_dissector.c

diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c
index f0516d9280c3563445ca259ff9f6aa759247d00e..0985b9b14b804737888a59591d242a550ddc0556 100644 (file)
--- a/net/core/flow_dissector.c
+++ b/net/core/flow_dissector.c
@@ -8,6 +8,16 @@
 #include <linux/ppp_defs.h>
 #include <net/flow_keys.h>
 
+/* copy saddr & daddr, possibly using 64bit load/store
+ * Equivalent to :     flow->src = iph->saddr;
+ *                     flow->dst = iph->daddr;
+ */
+static void iph_to_flow_copy_addrs(struct flow_keys *flow, const struct iphdr *iph)
+{
+       BUILD_BUG_ON(offsetof(typeof(*flow), dst) !=
+                    offsetof(typeof(*flow), src) + sizeof(flow->src));
+       memcpy(&flow->src, &iph->saddr, sizeof(flow->src) + sizeof(flow->dst));
+}
 
 bool skb_flow_dissect(const struct sk_buff *skb, struct flow_keys *flow)
 {
@@ -31,8 +41,7 @@ ip:
                        ip_proto = 0;
                else
                        ip_proto = iph->protocol;
-               flow->src = iph->saddr;
-               flow->dst = iph->daddr;
+               iph_to_flow_copy_addrs(flow, iph);
                nhoff += iph->ihl * 4;
                break;
        }