bool mf_are_prereqs_ok(const struct mf_field *, const struct flow *);
void mf_mask_field_and_prereqs(const struct mf_field *, struct flow *mask);
bool mf_are_prereqs_ok(const struct mf_field *, const struct flow *);
void mf_mask_field_and_prereqs(const struct mf_field *, struct flow *mask);