dma_alloc_coherent allocates memory that can be used by the cpu and the
device at the same time, calls to pci_dma_sync_* are not required, and in
fact actively harmful on some architectures like arm.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>