vsw_lookup_port
extern vsw_port_t *vsw_lookup_port(vsw_t *vswp, int p_instance);
portp = vsw_lookup_port(vswp, cport_num);
if ((port = vsw_lookup_port(vswp, p_instance)) == NULL) {
vsw_port_t *vsw_lookup_port(vsw_t *vswp, int p_instance);