Reference to Documentation/DMA-API-HOWTO.txt,
Streaming DMA mappings which are usually mapped for one DMA transfer,
Network card DMA ring descriptors should use Consistent DMA mappings.
Signed-off-by: NHuazhong Tan <tanhuazhong@huawei.com>
Signed-off-by: NPeng Li <lipeng321@huawei.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>