net: introduce rx_handler results and logic around that

This patch allows rx_handlers to better signalize what to do next to
it's caller. That makes skb->deliver_no_wcard no longer needed.

kernel-doc for rx_handler_result is taken from Nicolas' patch.

Signed-off-by: Jiri Pirko <jpirko@redhat.com>
Reviewed-by: Nicolas de Pesloüan <nicolas.2p.debian@free.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 18 insertions, 15 deletions

diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index 04119b1..27c413a 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -1480,20 +1480,23 @@ static bool bond_should_deliver_exact_match(struct sk_buff *skb,
 	return false;
 }
 
-static struct sk_buff *bond_handle_frame(struct sk_buff *skb)
+static rx_handler_result_t bond_handle_frame(struct sk_buff **pskb)
 {
+	struct sk_buff *skb = *pskb;
 	struct slave *slave;
 	struct net_device *bond_dev;
 	struct bonding *bond;
 
-	skb = skb_share_check(skb, GFP_ATOMIC);
-	if (unlikely(!skb))
-		return NULL;
-
 	slave = bond_slave_get_rcu(skb->dev);
 	bond_dev = ACCESS_ONCE(slave->dev->master);
 	if (unlikely(!bond_dev))
-		return skb;
+		return RX_HANDLER_PASS;
+
+	skb = skb_share_check(skb, GFP_ATOMIC);
+	if (unlikely(!skb))
+		return RX_HANDLER_CONSUMED;
+
+	*pskb = skb;
 
 	bond = netdev_priv(bond_dev);
 
@@ -1501,8 +1504,7 @@ static struct sk_buff *bond_handle_frame(struct sk_buff *skb)
 		slave->dev->last_rx = jiffies;
 
 	if (bond_should_deliver_exact_match(skb, slave, bond)) {
-		skb->deliver_no_wcard = 1;
-		return skb;
+		return RX_HANDLER_EXACT;
 	}
 
 	skb->dev = bond_dev;
@@ -1514,12 +1516,12 @@ static struct sk_buff *bond_handle_frame(struct sk_buff *skb)
 		if (unlikely(skb_cow_head(skb,
 					  skb->data - skb_mac_header(skb)))) {
 			kfree_skb(skb);
-			return NULL;
+			return RX_HANDLER_CONSUMED;
 		}
 		memcpy(eth_hdr(skb)->h_dest, bond_dev->dev_addr, ETH_ALEN);
 	}
 
-	return skb;
+	return RX_HANDLER_ANOTHER;
 }
 
 /* enslave device <slave> to bond device <master> */
diff --git a/drivers/net/macvlan.c b/drivers/net/macvlan.c
index 497991b..5b37d3c 100644
--- a/drivers/net/macvlan.c
+++ b/drivers/net/macvlan.c
@@ -152,9 +152,10 @@ static void macvlan_broadcast(struct sk_buff *skb,
 }
 
 /* called under rcu_read_lock() from netif_receive_skb */
-static struct sk_buff *macvlan_handle_frame(struct sk_buff *skb)
+static rx_handler_result_t macvlan_handle_frame(struct sk_buff **pskb)
 {
 	struct macvlan_port *port;
+	struct sk_buff *skb = *pskb;
 	const struct ethhdr *eth = eth_hdr(skb);
 	const struct macvlan_dev *vlan;
 	const struct macvlan_dev *src;
@@ -184,7 +185,7 @@ static struct sk_buff *macvlan_handle_frame(struct sk_buff *skb)
 			 */
 			macvlan_broadcast(skb, port, src->dev,
 					  MACVLAN_MODE_VEPA);
-		return skb;
+		return RX_HANDLER_PASS;
 	}
 
 	if (port->passthru)
@@ -192,12 +193,12 @@ static struct sk_buff *macvlan_handle_frame(struct sk_buff *skb)
 	else
 		vlan = macvlan_hash_lookup(port, eth->h_dest);
 	if (vlan == NULL)
-		return skb;
+		return RX_HANDLER_PASS;
 
 	dev = vlan->dev;
 	if (unlikely(!(dev->flags & IFF_UP))) {
 		kfree_skb(skb);
-		return NULL;
+		return RX_HANDLER_CONSUMED;
 	}
 	len = skb->len + ETH_HLEN;
 	skb = skb_share_check(skb, GFP_ATOMIC);
@@ -211,7 +212,7 @@ static struct sk_buff *macvlan_handle_frame(struct sk_buff *skb)
 
 out:
 	macvlan_count_rx(vlan, len, ret == NET_RX_SUCCESS, 0);
-	return NULL;
+	return RX_HANDLER_CONSUMED;
 }
 
 static int macvlan_queue_xmit(struct sk_buff *skb, struct net_device *dev)