XS_RING_SIZE
uint8_t xsr_req[XS_RING_SIZE];
uint8_t xsr_rsp[XS_RING_SIZE];
KASSERT(prod - cons <= XS_RING_SIZE);
return (req ? XS_RING_SIZE - (prod - cons) : prod - cons);
chunk = xs_ring_put(xs, bp, MIN(len, XS_RING_SIZE));
uint32_t prod = xsr->xsr_req_prod & (XS_RING_SIZE - 1);
if (size > XS_RING_SIZE)
left = XS_RING_SIZE - prod;
uint32_t cons = xsr->xsr_rsp_cons & (XS_RING_SIZE - 1);
if (size > XS_RING_SIZE)
left = XS_RING_SIZE - cons;