Re: [PATCH v4 1/6] iommu: Add a per domain PASID for DMA API

[Jason Gunthorpe]

On Tue, May 31, 2022 at 10:29:55AM -0700, Jacob Pan wrote:

> The reason why I store PASID at IOMMU domain is for IOTLB flush within the
> domain. Device driver is not aware of domain level IOTLB flush. We also
> have iova_cookie for each domain which essentially is for RIDPASID.

You need to make the PASID stuff work generically.

The domain needs to hold a list of all the places it needs to flush
and that list needs to be maintained during attach/detach.

A single PASID on the domain is obviously never going to work
generically.

Jason