void odp_flow_key_from_flow(struct ofpbuf *, const struct flow *);
int odp_flow_key_to_flow(const struct nlattr *, size_t, struct flow *);
void odp_flow_key_from_flow(struct ofpbuf *, const struct flow *);
int odp_flow_key_to_flow(const struct nlattr *, size_t, struct flow *);