On Tue, Aug 09, 2022 at 08:46:13AM +0200, Christoph Hellwig wrote: > - the design seems to ignore DMA ownership. Every time data in > transfered data needs to be transferred to and from the device, > take a look at Documentation/core-api/dma-api.rst and > Documentation/core-api/dma-api-howto.rst. I have this doing appropriate dma_sync_single_for_{device,cpu} if we aren't using coherent memory. Is there more to ownership beyond that?