[PATCH v10 09/10] iommufd: Add data structure for Intel VT-d stage-1 cache invalidation

[Yi Liu]

This adds the data structure invalidating caches for the nested domain
allocated with IOMMU_HWPT_DATA_VTD_S1 type.

Reviewed-by: Kevin Tian <kevin.tian@xxxxxxxxx>
Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx>
Signed-off-by: Yi Liu <yi.l.liu@xxxxxxxxx>
---
 include/uapi/linux/iommufd.h | 58 ++++++++++++++++++++++++++++++++++++
 1 file changed, 58 insertions(+)

diff --git a/include/uapi/linux/iommufd.h b/include/uapi/linux/iommufd.h
index 824560c50ec6..37c778055201 100644
--- a/include/uapi/linux/iommufd.h
+++ b/include/uapi/linux/iommufd.h
@@ -623,6 +623,64 @@ enum iommu_hwpt_invalidate_data_type {
 	IOMMU_HWPT_INVALIDATE_DATA_VTD_S1,
 };
 
+/**
+ * enum iommu_hwpt_vtd_s1_invalidate_flags - Flags for Intel VT-d
+ *                                           stage-1 cache invalidation
+ * @IOMMU_VTD_INV_FLAGS_LEAF: Indicates whether the invalidation applies
+ *                            to all-levels page structure cache or just
+ *                            the leaf PTE cache.
+ */
+enum iommu_hwpt_vtd_s1_invalidate_flags {
+	IOMMU_VTD_INV_FLAGS_LEAF = 1 << 0,
+};
+
+/**
+ * enum iommu_hwpt_vtd_s1_invalidate_error - Hardware error of invalidation
+ * @IOMMU_HWPT_INVALIDATE_VTD_S1_ICE: Invalidation Completion Error, details
+ *                                    refer to 11.4.7.1 Fault Status Register
+ *                                    of VT-d specification.
+ * @IOMMU_HWPT_INVALIDATE_VTD_S1_ITE: Invalidation Time-out Error, details
+ *                                    refer to 11.4.7.1 Fault Status Register
+ *                                    of VT-d specification.
+ */
+enum iommu_hwpt_vtd_s1_invalidate_error {
+	IOMMU_HWPT_INVALIDATE_VTD_S1_ICE = 1 << 0,
+	IOMMU_HWPT_INVALIDATE_VTD_S1_ITE = 1 << 1,
+};
+
+/**
+ * struct iommu_hwpt_vtd_s1_invalidate - Intel VT-d cache invalidation
+ *                                       (IOMMU_HWPT_INVALIDATE_DATA_VTD_S1)
+ * @addr: The start address of the range to be invalidated. It needs to
+ *        be 4KB aligned.
+ * @npages: Number of contiguous 4K pages to be invalidated.
+ * @flags: Combination of enum iommu_hwpt_vtd_s1_invalidate_flags
+ * @hw_error: One of enum iommu_hwpt_vtd_s1_invalidate_error
+ *
+ * The Intel VT-d specific invalidation data for user-managed stage-1 cache
+ * invalidation in nested translation. Userspace uses this structure to
+ * tell the impacted cache scope after modifying the stage-1 page table.
+ *
+ * Invalidating all the caches related to the page table by setting @addr
+ * to be 0 and @npages to be U64_MAX.
+ *
+ * The device TLB will be invalidated automatically if ATS is enabled.
+ *
+ * An entry is considered 'handled' after it passes the audit and submitted
+ * to the IOMMU by the underlying driver. Check the @entry_num output of
+ * struct iommu_hwpt_invalidate for the number of handled entries. A 'handled'
+ * request may still fail in hardware for various reasons, e.g. due to timeout
+ * on waiting for device response upon a device TLB invalidation request. In
+ * such case the hardware error info is reported in the @hw_error field of the
+ * handled entry.
+ */
+struct iommu_hwpt_vtd_s1_invalidate {
+	__aligned_u64 addr;
+	__aligned_u64 npages;
+	__u32 flags;
+	__u32 hw_error;
+};
+
 /**
  * struct iommu_hwpt_invalidate - ioctl(IOMMU_HWPT_INVALIDATE)
  * @size: sizeof(struct iommu_hwpt_invalidate)
-- 
2.34.1