On Wed, May 11, 2022 at 10:02:16AM -0700, Jacob Pan wrote: > > > If not global, perhaps we could have a list of pasids (e.g. xarray) > > > attached to the device_domain_info. The TLB flush logic would just go > > > through the list w/o caring what the PASIDs are for. Does it make sense > > > to you? > > > > Sort of, but we shouldn't duplicate xarrays - the group already has > > this xarray - need to find some way to allow access to it from the > > driver. > > > I am not following, here are the PASIDs for devTLB flush which is per > device. Why group? Because group is where the core code stores it. > We could retrieve PASIDs from the device PASID table but xa would be more > efficient. > > > > > > Are you suggesting the dma-iommu API should be called > > > > > iommu_set_dma_pasid instead of iommu_attach_dma_pasid? > > > > > > > > No that API is Ok - the driver ops API should be 'set' not > > > > attach/detach > > > Sounds good, this operation has little in common with > > > domain_ops.dev_attach_pasid() used by SVA domain. So I will add a new > > > domain_ops.dev_set_pasid() > > > > What? No, their should only be one operation, 'dev_set_pasid' and it > > is exactly the same as the SVA operation. It configures things so that > > any existing translation on the PASID is removed and the PASID > > translates according to the given domain. > > > > SVA given domain or UNMANAGED given domain doesn't matter to the > > higher level code. The driver should implement per-domain ops as > > required to get the different behaviors. > Perhaps some code to clarify, we have > sva_domain_ops.dev_attach_pasid() = intel_svm_attach_dev_pasid; > default_domain_ops.dev_attach_pasid() = intel_iommu_attach_dev_pasid; Yes, keep that structure > Consolidate pasid programming into dev_set_pasid() then called by both > intel_svm_attach_dev_pasid() and intel_iommu_attach_dev_pasid(), right? I was only suggesting that really dev_attach_pasid() op is misnamed, it should be called set_dev_pasid() and act like a set, not a paired attach/detach - same as the non-PASID ops. Jason
