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, 16 insertions, 11 deletions

diff --git a/net/bridge/br_input.c b/net/bridge/br_input.c
index 88e4aa9cb1f9..e2160792e1bc 100644
--- a/net/bridge/br_input.c
+++ b/net/bridge/br_input.c
@@ -139,21 +139,22 @@ static inline int is_link_local(const unsigned char *dest)
  * Return NULL if skb is handled
  * note: already called with rcu_read_lock
  */
-struct sk_buff *br_handle_frame(struct sk_buff *skb)
+rx_handler_result_t br_handle_frame(struct sk_buff **pskb)
 {
         struct net_bridge_port *p;
+        struct sk_buff *skb = *pskb;
         const unsigned char *dest = eth_hdr(skb)->h_dest;
         br_should_route_hook_t *rhook;
 
         if (unlikely(skb->pkt_type == PACKET_LOOPBACK))
-                return skb;
+                return RX_HANDLER_PASS;
 
         if (!is_valid_ether_addr(eth_hdr(skb)->h_source))
                 goto drop;
 
         skb = skb_share_check(skb, GFP_ATOMIC);
         if (!skb)
-                return NULL;
+                return RX_HANDLER_CONSUMED;
 
         p = br_port_get_rcu(skb->dev);
 
@@ -167,10 +168,12 @@ struct sk_buff *br_handle_frame(struct sk_buff *skb)
                         goto forward;
 
                 if (NF_HOOK(NFPROTO_BRIDGE, NF_BR_LOCAL_IN, skb, skb->dev,
-                            NULL, br_handle_local_finish))
-                        return NULL;    /* frame consumed by filter */
-                else
-                        return skb;     /* continue processing */
+                            NULL, br_handle_local_finish)) {
+                        return RX_HANDLER_CONSUMED; /* consumed by filter */
+                } else {
+                        *pskb = skb;
+                        return RX_HANDLER_PASS; /* continue processing */
+                }
         }
 
 forward:
@@ -178,8 +181,10 @@ forward:
         case BR_STATE_FORWARDING:
                 rhook = rcu_dereference(br_should_route_hook);
                 if (rhook) {
-                        if ((*rhook)(skb))
-                                return skb;
+                        if ((*rhook)(skb)) {
+                                *pskb = skb;
+                                return RX_HANDLER_PASS;
+                        }
                         dest = eth_hdr(skb)->h_dest;
                 }
                 /* fall through */
@@ -194,5 +199,5 @@ forward:
 drop:
                 kfree_skb(skb);
         }
-        return NULL;
+        return RX_HANDLER_CONSUMED;
 }
diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h
index f7afc364d777..19e2f46ed086 100644
--- a/net/bridge/br_private.h
+++ b/net/bridge/br_private.h
@@ -379,7 +379,7 @@ extern void br_features_recompute(struct net_bridge *br);
 
 /* br_input.c */
 extern int br_handle_frame_finish(struct sk_buff *skb);
-extern struct sk_buff *br_handle_frame(struct sk_buff *skb);
+extern rx_handler_result_t br_handle_frame(struct sk_buff **pskb);
 
 /* br_ioctl.c */
 extern int br_dev_ioctl(struct net_device *dev, struct ifreq *rq, int cmd);