Re: [PATCH v2 1/5] iommufd: Add nesting related data structures for Intel VT-d

From: Liu, Jingqi
Date: Wed Mar 15 2023 - 09:51:09 EST



On 3/9/2023 4:22 PM, Yi Liu wrote:
Add the following data structures for corresponding ioctls:
iommu_hwpt_intel_vtd => IOMMU_HWPT_ALLOC
iommu_hw_info_vtd => IOMMU_DEVICE_GET_HW_INFO
iommu_hwpt_invalidate_intel_vtd => IOMMU_HWPT_INVALIDATE

Also, add IOMMU_HW_INFO_TYPE_INTEL_VTD and IOMMU_HWPT_TYPE_VTD_S1 to the
header and corresponding type/size arrays.

Signed-off-by: Yi Liu <yi.l.liu@xxxxxxxxx>
---
drivers/iommu/iommufd/hw_pagetable.c | 7 +-
drivers/iommu/iommufd/main.c | 5 +
include/uapi/linux/iommufd.h | 136 +++++++++++++++++++++++++++
3 files changed, 147 insertions(+), 1 deletion(-)

[...]

+
+/**
+ * struct iommu_hwpt_intel_vtd - Intel VT-d specific user-managed
+ * stage-1 page table info
+ * @flags: Combination of enum iommu_hwpt_intel_vtd_flags
+ * @pgtbl_addr: The base address of the user-managed stage-1 page table.
+ * @pat: Page attribute table data to compute effective memory type
+ * @emt: Extended memory type
+ * @addr_width: The address width of the untranslated addresses that are
+ * subjected to the user-managed stage-1 page table.
+ * @__reserved: Must be 0
+ *
+ * The Intel VT-d specific data for creating hw_pagetable to represent
+ * the user-managed stage-1 page table that is used in nested translation.
+ *
+ * In nested translation, the stage-1 page table locates in the address
+ * space that defined by the corresponding stage-2 page table. Hence the
+ * stage-1 page table base address value should not be higher than the
+ * maximum untranslated address of stage-2 page table.
+ *
+ * The paging level of the stage-1 page table should be compataible with

s/compataible/compatible

+ * the hardware iommu. Otherwise, the allocation would be failed.
+ */
+struct iommu_hwpt_intel_vtd {
+ __u64 flags;
+ __u64 pgtbl_addr;
+ __u32 pat;
+ __u32 emt;
+ __u32 addr_width;
+ __u32 __reserved;
};

[...]

+
+/**
+ * struct iommu_hwpt_invalidate_intel_vtd - Intel VT-d cache invalidation info
+ * @granularity: One of enum iommu_vtd_qi_granularity.
+ * @flags: Combination of enum iommu_hwpt_intel_vtd_invalidate_flags
+ * @__reserved: Must be 0
+ * @addr: The start address of the addresses to be invalidated.
+ * @granule_size: Page/block size of the mapping in bytes. It is used to
+ * compute the invalidation range togehter with @nb_granules.

s/togehter/together

Thanks,
Jingqi