Symbol: USABLE_TX_BD
sys/dev/netif/bce/if_bce.c
3977
txr->max_tx_bd = USABLE_TX_BD(txr);
sys/dev/netif/bce/if_bce.c
978
ifq_set_maxlen(&ifp->if_snd, USABLE_TX_BD(&sc->tx_rings[0]));