skbuff: Make __skb_set_sw_hash a general function

Move __skb_set_sw_hash to skbuff.h and add __skb_set_hash which is
a common method (between __skb_set_sw_hash and skb_set_hash) to set
the hash in an skbuff.

Also, move skb_clear_hash to be closer to __skb_set_hash.

Signed-off-by: Tom Herbert <[email protected]>
Signed-off-by: David S. Miller <[email protected]>

Author: tomratbert

include/linux/skbuff.h

@@ -937,14 +937,40 @@ enum pkt_hash_types {
 	PKT_HASH_TYPE_L4,	/* Input: src_IP, dst_IP, src_port, dst_port */
 };
 
-static inline void
-skb_set_hash(struct sk_buff *skb, __u32 hash, enum pkt_hash_types type)
+static inline void skb_clear_hash(struct sk_buff *skb)
 {
-	skb->l4_hash = (type == PKT_HASH_TYPE_L4);
+	skb->hash = 0;
 	skb->sw_hash = 0;
+	skb->l4_hash = 0;
+}
+
+static inline void skb_clear_hash_if_not_l4(struct sk_buff *skb)
+{
+	if (!skb->l4_hash)
+		skb_clear_hash(skb);
+}
+
+static inline void
+__skb_set_hash(struct sk_buff *skb, __u32 hash, bool is_sw, bool is_l4)
+{
+	skb->l4_hash = is_l4;
+	skb->sw_hash = is_sw;
 	skb->hash = hash;
 }
 
+static inline void
+skb_set_hash(struct sk_buff *skb, __u32 hash, enum pkt_hash_types type)
+{
+	/* Used by drivers to set hash from HW */
+	__skb_set_hash(skb, hash, false, type == PKT_HASH_TYPE_L4);
+}
+
+static inline void
+__skb_set_sw_hash(struct sk_buff *skb, __u32 hash, bool is_l4)
+{
+	__skb_set_hash(skb, hash, true, is_l4);
+}
+
 void __skb_get_hash(struct sk_buff *skb);
 u32 skb_get_poff(const struct sk_buff *skb);
 u32 __skb_get_poff(const struct sk_buff *skb, void *data,
@@ -1027,19 +1053,6 @@ static inline __u32 skb_get_hash_raw(const struct sk_buff *skb)
 	return skb->hash;
 }
 
-static inline void skb_clear_hash(struct sk_buff *skb)
-{
-	skb->hash = 0;
-	skb->sw_hash = 0;
-	skb->l4_hash = 0;
-}
-
-static inline void skb_clear_hash_if_not_l4(struct sk_buff *skb)
-{
-	if (!skb->l4_hash)
-		skb_clear_hash(skb);
-}
-
 static inline void skb_copy_hash(struct sk_buff *to, const struct sk_buff *from)
 {
 	to->hash = from->hash;

include/net/flow_dissector.h

@@ -167,4 +167,9 @@ struct flow_keys_digest {
 void make_flow_keys_digest(struct flow_keys_digest *digest,
 			   const struct flow_keys *flow);
 
+static inline bool flow_keys_have_l4(struct flow_keys *keys)
+{
+	return (keys->ports.ports || keys->tags.flow_label);
+}
+
 #endif

net/core/flow_dissector.c

@@ -590,15 +590,6 @@ void make_flow_keys_digest(struct flow_keys_digest *digest,
 }
 EXPORT_SYMBOL(make_flow_keys_digest);
 
-static inline void __skb_set_sw_hash(struct sk_buff *skb, u32 hash,
-				     struct flow_keys *keys)
-{
-	if (keys->ports.ports)
-		skb->l4_hash = 1;
-	skb->sw_hash = 1;
-	skb->hash = hash;
-}
-
 /**
  * __skb_get_hash: calculate a flow hash
  * @skb: sk_buff to calculate flow hash from
@@ -619,7 +610,8 @@ void __skb_get_hash(struct sk_buff *skb)
 	if (!hash)
 		return;
 
-	__skb_set_sw_hash(skb, hash, &keys);
+	__skb_set_sw_hash(skb, hash,
+			  flow_keys_have_l4(&keys));
 }
 EXPORT_SYMBOL(__skb_get_hash);
 
@@ -648,7 +640,8 @@ __u32 __skb_get_hash_flowi6(struct sk_buff *skb, struct flowi6 *fl6)
 	keys.tags.flow_label = (__force u32)fl6->flowlabel;
 	keys.basic.ip_proto = fl6->flowi6_proto;
 
-	__skb_set_sw_hash(skb, flow_hash_from_keys(&keys), &keys);
+	__skb_set_sw_hash(skb, flow_hash_from_keys(&keys),
+			  flow_keys_have_l4(&keys));
 
 	return skb->hash;
 }
@@ -668,7 +661,8 @@ __u32 __skb_get_hash_flowi4(struct sk_buff *skb, struct flowi4 *fl4)
 	keys.keyid.keyid = fl4->fl4_gre_key;
 	keys.basic.ip_proto = fl4->flowi4_proto;
 
-	__skb_set_sw_hash(skb, flow_hash_from_keys(&keys), &keys);
+	__skb_set_sw_hash(skb, flow_hash_from_keys(&keys),
+			  flow_keys_have_l4(&keys));
 
 	return skb->hash;
 }