openvswitch: Refactor ovs_nla_fill_match().

Refactor the ovs_nla_fill_match() function into separate netlink
serialization functions ovs_nla_put_{unmasked_key,mask}(). Modify
ovs_nla_put_flow() to handle attribute nesting and expose the 'is_mask'
parameter - all callers need to nest the flow, and callers have better
knowledge about whether it is serializing a mask or not.

Signed-off-by: Joe Stringer <joestringer@nicira.com>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

net/openvswitch/datapath.c

@@ -461,10 +461,8 @@ static int queue_userspace_packet(struct datapath *dp, struct sk_buff *skb,
 			     0, upcall_info->cmd);
 	upcall->dp_ifindex = dp_ifindex;
 
-	nla = nla_nest_start(user_skb, OVS_PACKET_ATTR_KEY);
-	err = ovs_nla_put_flow(key, key, user_skb);
+	err = ovs_nla_put_key(key, key, OVS_PACKET_ATTR_KEY, false, user_skb);
 	BUG_ON(err);
-	nla_nest_end(user_skb, nla);
 
 	if (upcall_info->userdata)
 		__nla_put(user_skb, OVS_PACKET_ATTR_USERDATA,
@@ -675,37 +673,6 @@ static size_t ovs_flow_cmd_msg_size(const struct sw_flow_actions *acts)
 		+ nla_total_size(acts->actions_len); /* OVS_FLOW_ATTR_ACTIONS */
 }
 
-/* Called with ovs_mutex or RCU read lock. */
-static int ovs_flow_cmd_fill_match(const struct sw_flow *flow,
-				   struct sk_buff *skb)
-{
-	struct nlattr *nla;
-	int err;
-
-	/* Fill flow key. */
-	nla = nla_nest_start(skb, OVS_FLOW_ATTR_KEY);
-	if (!nla)
-		return -EMSGSIZE;
-
-	err = ovs_nla_put_flow(&flow->unmasked_key, &flow->unmasked_key, skb);
-	if (err)
-		return err;
-
-	nla_nest_end(skb, nla);
-
-	/* Fill flow mask. */
-	nla = nla_nest_start(skb, OVS_FLOW_ATTR_MASK);
-	if (!nla)
-		return -EMSGSIZE;
-
-	err = ovs_nla_put_flow(&flow->key, &flow->mask->key, skb);
-	if (err)
-		return err;
-
-	nla_nest_end(skb, nla);
-	return 0;
-}
-
 /* Called with ovs_mutex or RCU read lock. */
 static int ovs_flow_cmd_fill_stats(const struct sw_flow *flow,
 				   struct sk_buff *skb)
@@ -787,7 +754,11 @@ static int ovs_flow_cmd_fill_info(const struct sw_flow *flow, int dp_ifindex,
 
 	ovs_header->dp_ifindex = dp_ifindex;
 
-	err = ovs_flow_cmd_fill_match(flow, skb);
+	err = ovs_nla_put_unmasked_key(flow, skb);
+	if (err)
+		goto error;
+
+	err = ovs_nla_put_mask(flow, skb);
 	if (err)
 		goto error;
 

net/openvswitch/flow_netlink.c

@@ -1216,12 +1216,12 @@ int ovs_nla_get_flow_metadata(const struct nlattr *attr,
 	return metadata_from_nlattrs(&match, &attrs, a, false, log);
 }
 
-int ovs_nla_put_flow(const struct sw_flow_key *swkey,
-		     const struct sw_flow_key *output, struct sk_buff *skb)
+static int __ovs_nla_put_key(const struct sw_flow_key *swkey,
+			     const struct sw_flow_key *output, bool is_mask,
+			     struct sk_buff *skb)
 {
 	struct ovs_key_ethernet *eth_key;
 	struct nlattr *nla, *encap;
-	bool is_mask = (swkey != output);
 
 	if (nla_put_u32(skb, OVS_KEY_ATTR_RECIRC_ID, output->recirc_id))
 		goto nla_put_failure;
@@ -1431,6 +1431,38 @@ nla_put_failure:
 	return -EMSGSIZE;
 }
 
+int ovs_nla_put_key(const struct sw_flow_key *swkey,
+		    const struct sw_flow_key *output, int attr, bool is_mask,
+		    struct sk_buff *skb)
+{
+	int err;
+	struct nlattr *nla;
+
+	nla = nla_nest_start(skb, attr);
+	if (!nla)
+		return -EMSGSIZE;
+	err = __ovs_nla_put_key(swkey, output, is_mask, skb);
+	if (err)
+		return err;
+	nla_nest_end(skb, nla);
+
+	return 0;
+}
+
+/* Called with ovs_mutex or RCU read lock. */
+int ovs_nla_put_unmasked_key(const struct sw_flow *flow, struct sk_buff *skb)
+{
+	return ovs_nla_put_key(&flow->unmasked_key, &flow->unmasked_key,
+				OVS_FLOW_ATTR_KEY, false, skb);
+}
+
+/* Called with ovs_mutex or RCU read lock. */
+int ovs_nla_put_mask(const struct sw_flow *flow, struct sk_buff *skb)
+{
+	return ovs_nla_put_key(&flow->key, &flow->mask->key,
+				OVS_FLOW_ATTR_MASK, true, skb);
+}
+
 #define MAX_ACTIONS_BUFSIZE	(32 * 1024)
 
 static struct sw_flow_actions *nla_alloc_flow_actions(int size, bool log)

net/openvswitch/flow_netlink.h

@@ -43,11 +43,14 @@ size_t ovs_key_attr_size(void);
 void ovs_match_init(struct sw_flow_match *match,
 		    struct sw_flow_key *key, struct sw_flow_mask *mask);
 
-int ovs_nla_put_flow(const struct sw_flow_key *,
-		     const struct sw_flow_key *, struct sk_buff *);
+int ovs_nla_put_key(const struct sw_flow_key *, const struct sw_flow_key *,
+		    int attr, bool is_mask, struct sk_buff *);
 int ovs_nla_get_flow_metadata(const struct nlattr *, struct sw_flow_key *,
 			      bool log);
 
+int ovs_nla_put_unmasked_key(const struct sw_flow *flow, struct sk_buff *skb);
+int ovs_nla_put_mask(const struct sw_flow *flow, struct sk_buff *skb);
+
 int ovs_nla_get_match(struct sw_flow_match *, const struct nlattr *key,
 		      const struct nlattr *mask, bool log);
 int ovs_nla_put_egress_tunnel_key(struct sk_buff *,