Introduce IOMMU_HWPT_DATA_AMD_V2 data type for AMD IOMMU v2 page table,
which is used for stage-1 in nested translation. The data structure
contains information necessary for setting up the AMD HW-vIOMMU support.

Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
---
 include/uapi/linux/iommufd.h | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)

diff --git a/include/uapi/linux/iommufd.h b/include/uapi/linux/iommufd.h
index 9901b9f4abe2..b28ec5947571 100644
--- a/include/uapi/linux/iommufd.h
+++ b/include/uapi/linux/iommufd.h
@@ -389,14 +389,39 @@ struct iommu_hwpt_vtd_s1 {
 	__u32 __reserved;
 };
 
+/**
+ * struct iommu_hwpt_amd_v2 - AMD IOMMU specific user-managed
+ *                            v2 I/O page table data
+ * @gcr3: GCR3 guest physical ddress
+ * @flags.glx: GCR3 table levels
+ * @flags.giov: GIOV mode
+ * @flags.guest_paging_mode: Guest v2 page table paging mode
+ * @flags.reserved : Must be 0
+ * @gdom_id: Guest domain ID
+ * @__reserved: Must be 0
+ */
+struct iommu_hwpt_amd_v2 {
+	__aligned_u64 gcr3;
+	struct {
+		__aligned_u64 glx  : 1,
+			      giov : 1,
+			      guest_paging_mode : 2,
+			      reserved : 60;
+	} flags;
+	__u32 gdom_id;
+	__u32 __reserved;
+};
+
 /**
  * enum iommu_hwpt_data_type - IOMMU HWPT Data Type
  * @IOMMU_HWPT_DATA_NONE: no data
  * @IOMMU_HWPT_DATA_VTD_S1: Intel VT-d stage-1 page table
+ * @IOMMU_HWPT_DATA_AMD_V2: AMD IOMMUv2 page table
  */
 enum iommu_hwpt_data_type {
 	IOMMU_HWPT_DATA_NONE,
 	IOMMU_HWPT_DATA_VTD_S1,
+	IOMMU_HWPT_DATA_AMD_V2,
 };
 
 /**
-- 
2.34.1

On Thu, Jan 11, 2024 at 06:06:44PM -0600, Suravee Suthikulpanit wrote:
> Introduce IOMMU_HWPT_DATA_AMD_V2 data type for AMD IOMMU v2 page table,
> which is used for stage-1 in nested translation. The data structure
> contains information necessary for setting up the AMD HW-vIOMMU support.
> 
> Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
> ---
>  include/uapi/linux/iommufd.h | 25 +++++++++++++++++++++++++
>  1 file changed, 25 insertions(+)
> 
> diff --git a/include/uapi/linux/iommufd.h b/include/uapi/linux/iommufd.h
> index 9901b9f4abe2..b28ec5947571 100644
> --- a/include/uapi/linux/iommufd.h
> +++ b/include/uapi/linux/iommufd.h
> @@ -389,14 +389,39 @@ struct iommu_hwpt_vtd_s1 {
>  	__u32 __reserved;
>  };
>  
> +/**
> + * struct iommu_hwpt_amd_v2 - AMD IOMMU specific user-managed
> + *                            v2 I/O page table data
> + * @gcr3: GCR3 guest physical ddress
> + * @flags.glx: GCR3 table levels
> + * @flags.giov: GIOV mode
> + * @flags.guest_paging_mode: Guest v2 page table paging mode
> + * @flags.reserved : Must be 0
> + * @gdom_id: Guest domain ID
> + * @__reserved: Must be 0
> + */
> +struct iommu_hwpt_amd_v2 {
> +	__aligned_u64 gcr3;
> +	struct {
> +		__aligned_u64 glx  : 1,
> +			      giov : 1,
> +			      guest_paging_mode : 2,
> +			      reserved : 60;
> +	} flags;

IIRC you should not put bitfileds in UAPI headers..

I suggest this should just be something like:

__aligned_u64 dte[3];

And you actually just copy bits directly from the vDTE to the pDTE.

Jason

> From: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
> Sent: Friday, January 12, 2024 8:07 AM
> 
> +/**
> + * struct iommu_hwpt_amd_v2 - AMD IOMMU specific user-managed
> + *                            v2 I/O page table data
> + * @gcr3: GCR3 guest physical ddress
> + * @flags.glx: GCR3 table levels
> + * @flags.giov: GIOV mode
> + * @flags.guest_paging_mode: Guest v2 page table paging mode
> + * @flags.reserved : Must be 0
> + * @gdom_id: Guest domain ID
> + * @__reserved: Must be 0
> + */
> +struct iommu_hwpt_amd_v2 {
> +	__aligned_u64 gcr3;
> +	struct {
> +		__aligned_u64 glx  : 1,
> +			      giov : 1,

My impression was that giov allows non-PASID requests to be treated
as if tagged with pasid#0. kind of a prerequisite for enabling nested
translation? how does it work if guest disables it?

> +			      guest_paging_mode : 2,
> +			      reserved : 60;
> +	} flags;
> +	__u32 gdom_id;

this is not used in this series.