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 04119b1e7cdb..27c413aa15da 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 497991bd3b64..5b37d3c191e4 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)