rw_enter
err = rw_enter(&sc->ioctl_rwl, RW_WRITE | RW_INTR);
err = rw_enter(&sc->ioctl_rwl, RW_WRITE | RW_INTR);
error = rw_enter(&sc->sc_rwlock, RW_WRITE | RW_INTR);
return rw_enter(rwl, RW_WRITE);