NICVF_RCV_BUF_ALIGN_BYTES
#define GET_RBUF_INFO(x) ((struct rbuf_info *)((x) - NICVF_RCV_BUF_ALIGN_BYTES))
m_adj(mbuf, NICVF_RCV_BUF_ALIGN_BYTES);
*rbuf = segs[0].ds_addr + NICVF_RCV_BUF_ALIGN_BYTES;
sizeof(struct rbdr_entry_t), NICVF_RCV_BUF_ALIGN_BYTES);
rbdr->dma_size = buf_size - NICVF_RCV_BUF_ALIGN_BYTES;
NICVF_RCV_BUF_ALIGN_BYTES, /* alignment */
(NICVF_ALIGNED_ADDR((addr), NICVF_RCV_BUF_ALIGN_BYTES) - (addr))