RE: [RFC 8/8] iommu/vt-d: Add set_dev_pasid callback for nested domain

[Tian, Kevin]

> From: Liu, Yi L <yi.l.liu@xxxxxxxxx>
> Sent: Tuesday, September 26, 2023 5:27 PM
> 
> From: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
> 
> This allows the upper layers to set a nested type domain to a PASID of a
> device if the PASID feature is supported by the IOMMU hardware.
> 
> Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
> Signed-off-by: Yi Liu <yi.l.liu@xxxxxxxxx>
> ---
>  drivers/iommu/intel/nested.c | 47
> ++++++++++++++++++++++++++++++++++++
>  1 file changed, 47 insertions(+)

pasid can be attached to either user hwpt or kernel hwpt.

We should also introduce a set_dev_pasid callback for non-nest domain ops.