struct sw_flow *chain_lookup(struct sw_chain *, const struct sw_flow_key *);
int chain_insert(struct sw_chain *, struct sw_flow *);
int chain_modify(struct sw_chain *, const struct sw_flow_key *,
struct sw_flow *chain_lookup(struct sw_chain *, const struct sw_flow_key *);
int chain_insert(struct sw_chain *, struct sw_flow *);
int chain_modify(struct sw_chain *, const struct sw_flow_key *,