rhine_tx_desc
static char desc1[TX_RING_SIZE * sizeof (struct rhine_tx_desc) + 32];
static char desc2[TX_RING_SIZE * sizeof (struct rhine_tx_desc) + 32];
tp->tx_ring = (struct rhine_tx_desc *) bus_to_virt (j);
struct rhine_tx_desc *tx_ring;