On Thu, Mar 10, 2016 at 11:10:10AM +0800, Jike Song wrote: > > >> Is it supposed to be the caller who should set > >> up IOMMU by DMA api such as dma_map_page(), after calling > >> vgpu_dma_do_translate()? > >> > > > > Don't think you need to call dma_map_page here. Once you have the pfn > > available > > to your GPU kernel driver, you can just go ahead to setup the mapping as you > > normally do such as calling pci_map_sg and its friends. > > > > Technically it's definitely OK to call DMA API from the caller rather than > here, > however personally I think it is a bit counter-intuitive: IOMMU page tables > should be constructed within the VFIO IOMMU driver. >
Hi Jike, For vGPU, what we have is just a virtual device and a fake IOMMU group, therefore the actual interaction with the real GPU should be managed by the GPU vendor driver. With the default TYPE1 IOMMU, it works with the vfio-pci as it owns the device. Thanks, Neo > -- > Thanks, > Jike >
