On Tue, Feb 22, 2022 at 09:06:48AM +0000, David Laight wrote: > From: Christoph Hellwig > > Sent: 22 February 2022 08:47 > ... > > > Hmm.. for this specific case, What about allocating two buffers > > > for DMA_TO_DEVICE and DMA_FROM_DEVICE at initialization time? > > > > That will work, but I don't see the benefit as you'd still need to call > > dma_sync_single* before and after each data transfer. > > For systems with an iommu that should save all the iommu setup > for every transfer. So does allocating a single buffer as in the patch we are replying to.
