datapath: Free up flow_extract() return value for reporting errors.

[sliver-openvswitch.git] / datapath / flow.c

diff --git a/datapath/flow.c b/datapath/flow.c
index a64152b..5e362e3 100644 (file)
--- a/datapath/flow.c
+++ b/datapath/flow.c
@@ -219,21 +219,28 @@ static __be16 parse_ethertype(struct sk_buff *skb)
        return llc->ethertype;
 }
 
-/* Parses the Ethernet frame in 'skb', which was received on 'in_port',
- * and initializes 'key' to match.  Returns 1 if 'skb' contains an IP
- * fragment, 0 otherwise. */
+/**
+ * flow_extract - extracts a flow key from an Ethernet frame.
+ * @skb: sk_buff that contains the frame, with skb->data pointing to the
+ * Ethernet header
+ * @in_port: port number on which @skb was received.
+ * @key: output flow key
+ *
+ * The caller must ensure that skb->len >= ETH_HLEN.
+ *
+ * Sets OVS_CB(skb)->is_frag to %true if @skb is an IPv4 fragment, otherwise to
+ * %false.
+ */
 int flow_extract(struct sk_buff *skb, u16 in_port, struct odp_flow_key *key)
 {
        struct ethhdr *eth;
-       int retval = 0;
 
        memset(key, 0, sizeof *key);
        key->tun_id = OVS_CB(skb)->tun_id;
        key->in_port = in_port;
        key->dl_vlan = htons(ODP_VLAN_NONE);
+       OVS_CB(skb)->is_frag = false;
 
-       if (skb->len < sizeof *eth)
-               return 0;
        if (!pskb_may_pull(skb, min(skb->len, 64u)))
                return 0;
 
@@ -302,7 +309,7 @@ int flow_extract(struct sk_buff *skb, u16 in_port, struct odp_flow_key *key)
                                }
                        }
                } else {
-                       retval = 1;
+                       OVS_CB(skb)->is_frag = true;
                }
        } else if (key->dl_type == htons(ETH_P_ARP) && arphdr_ok(skb)) {
                struct arp_eth_header *arp;
@@ -328,7 +335,7 @@ int flow_extract(struct sk_buff *skb, u16 in_port, struct odp_flow_key *key)
        } else {
                skb_reset_transport_header(skb);
        }
-       return retval;
+       return 0;
 }
 
 u32 flow_hash(const struct odp_flow_key *key)