RX_RING_MAXSIZE
struct be_rxd be_rxd[RX_RING_MAXSIZE];
struct happy_meal_rxd happy_meal_rxd[RX_RING_MAXSIZE];
&rxbase[(elem+RX_RING_SIZE)&(RX_RING_MAXSIZE-1)];
#define NEXT_RX(num) (((num) + 1) & (RX_RING_MAXSIZE - 1))
#define PREV_RX(num) (((num) - 1) & (RX_RING_MAXSIZE - 1))
struct qe_rxd qe_rxd[RX_RING_MAXSIZE];