diff options
Diffstat (limited to 'include/linux/skbuff.h')
| -rw-r--r-- | include/linux/skbuff.h | 40 |
1 files changed, 40 insertions, 0 deletions
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 7deb7ad6591..99846956dff 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -703,6 +703,46 @@ unsigned int skb_find_text(struct sk_buff *skb, unsigned int from, unsigned int to, struct ts_config *config, struct ts_state *state); +/* + * Packet hash types specify the type of hash in skb_set_hash. + * + * Hash types refer to the protocol layer addresses which are used to + * construct a packet's hash. The hashes are used to differentiate or identify + * flows of the protocol layer for the hash type. Hash types are either + * layer-2 (L2), layer-3 (L3), or layer-4 (L4). + * + * Properties of hashes: + * + * 1) Two packets in different flows have different hash values + * 2) Two packets in the same flow should have the same hash value + * + * A hash at a higher layer is considered to be more specific. A driver should + * set the most specific hash possible. + * + * A driver cannot indicate a more specific hash than the layer at which a hash + * was computed. For instance an L3 hash cannot be set as an L4 hash. + * + * A driver may indicate a hash level which is less specific than the + * actual layer the hash was computed on. For instance, a hash computed + * at L4 may be considered an L3 hash. This should only be done if the + * driver can't unambiguously determine that the HW computed the hash at + * the higher layer. Note that the "should" in the second property above + * permits this. + */ +enum pkt_hash_types { + PKT_HASH_TYPE_NONE, /* Undefined type */ + PKT_HASH_TYPE_L2, /* Input: src_MAC, dest_MAC */ + PKT_HASH_TYPE_L3, /* Input: src_IP, dst_IP */ + PKT_HASH_TYPE_L4, /* Input: src_IP, dst_IP, src_port, dst_port */ +}; + +static inline void +skb_set_hash(struct sk_buff *skb, __u32 hash, enum pkt_hash_types type) +{ + skb->l4_rxhash = (type == PKT_HASH_TYPE_L4); + skb->rxhash = hash; +} + void __skb_get_hash(struct sk_buff *skb); static inline __u32 skb_get_hash(struct sk_buff *skb) { |