flowi: Abstract out functions to get flow hash based on flowi

Create __get_hash_from_flowi6 and __get_hash_from_flowi4 to get the
flow keys and hash based on flowi structures. These are called by
__skb_get_hash_flowi6 and __skb_get_hash_flowi4. Also, created
get_hash_from_flowi6 and get_hash_from_flowi4 which can be called
when just the hash value for a flowi is needed.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/flow.h b/include/net/flow.h
index 9e0297c..dafe97c 100644
--- a/include/net/flow.h
+++ b/include/net/flow.h
@@ -10,6 +10,7 @@
 #include <linux/socket.h>
 #include <linux/in6.h>
 #include <linux/atomic.h>
+#include <net/flow_dissector.h>
 
 /*
  * ifindex generation is per-net namespace, and loopback is
@@ -243,4 +244,22 @@
 void flow_cache_flush_deferred(struct net *net);
 extern atomic_t flow_cache_genid;
 
+__u32 __get_hash_from_flowi6(struct flowi6 *fl6, struct flow_keys *keys);
+
+static inline __u32 get_hash_from_flowi6(struct flowi6 *fl6)
+{
+	struct flow_keys keys;
+
+	return __get_hash_from_flowi6(fl6, &keys);
+}
+
+__u32 __get_hash_from_flowi4(struct flowi4 *fl4, struct flow_keys *keys);
+
+static inline __u32 get_hash_from_flowi4(struct flowi4 *fl4)
+{
+	struct flow_keys keys;
+
+	return __get_hash_from_flowi4(fl4, &keys);
+}
+
 #endif