DPTR_ALIGN
buffer = PTR_ALIGN(priv->tx_align[q], DPTR_ALIGN) +
entry / num_tx_desc * DPTR_ALIGN;
len = PTR_ALIGN(skb->data, DPTR_ALIGN) - skb->data;
len = DPTR_ALIGN;
priv->tx_align[q] = kmalloc(DPTR_ALIGN * priv->num_tx_ring[q] +
DPTR_ALIGN - 1, GFP_KERNEL);