On Thu, Mar 23, 2023 at 08:15:44PM +0800, Nanyong Sun wrote: > On 2023/3/23 19:31, Jason Gunthorpe wrote: > > > On Thu, Mar 23, 2023 at 05:22:36PM +0800, Nanyong Sun wrote: > > > > A patch to export that function is alread posted: > > > > > > > > https://lore.kernel.org/linux-iommu/BN9PR11MB52760E9705F2985EACCD5C4A8CBA9@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/T/#u > > > > > > > > But I do not want VDPA to mis-use it unless it also implements all the > > > > ownership stuff properly. > > > > > > > I want to confirm if we need to introduce iommu group logic to vdpa, as "all > > > the ownership stuff" ? > > You have to call iommu_device_claim_dma_owner() > > > > But again, this is all pointless, iommufd takes are of all of this and > > VDPA should switch to it instead of more hacking. > > > > Jason > > . > Yeah, thanks for your suggestion，but as Michael and Jason Wang said, > before iommufd is ready, we may need to make vDPA work well on software > managed MSI platforms. > To achieve that, basically we have two ways: > > 1. export iommu_get_resv_regions, and get regions device by device. > 2. introduce iommu group, get regions by iommu_get_group_resv_regions, which > already exported. I do not think you should dig the hole deeper. If proper iommu support is important to you then you should invest in iommufd conversion. Jason
