vr_ring_t
static vr_result_t vr_alloc_ring(vr_t *vrp, vr_ring_t *r, size_t n);
static void vr_free_ring(vr_ring_t *r, size_t n);
vr_alloc_ring(vr_t *vrp, vr_ring_t *ring, size_t n)
vr_free_ring(vr_ring_t *r, size_t n)
vr_ring_t txring;
vr_ring_t rxring;