CLPSCOM_RING_SIZE
sc->sc_rbuf = kmem_alloc(CLPSCOM_RING_SIZE << 1, KM_SLEEP);
sc->sc_rbavail = CLPSCOM_RING_SIZE;
if (put >= sc->sc_rbuf + (CLPSCOM_RING_SIZE << 1))
sc->sc_rbavail = CLPSCOM_RING_SIZE;
scc = cc = CLPSCOM_RING_SIZE - sc->sc_rbavail;
if (get >= sc->sc_rbuf + (CLPSCOM_RING_SIZE << 1))
get -= (CLPSCOM_RING_SIZE << 1);
if (get >= sc->sc_rbuf + (CLPSCOM_RING_SIZE << 1))