rdsv3_ib_ring_alloc
avail = rdsv3_ib_ring_alloc(&ic->i_recv_ring, w_nr, &pos);
work_alloc = rdsv3_ib_ring_alloc(&ic->i_send_ring, op->r_count, &pos);
work_alloc = rdsv3_ib_ring_alloc(&ic->i_send_ring, i, &pos);
uint32_t rdsv3_ib_ring_alloc(struct rdsv3_ib_work_ring *ring, uint32_t val,