diff mbox series

[v7,2/9] iommufd: Add IOMMU_HWPT_INVALIDATE

Message ID 20231221153948.119007-3-yi.l.liu@intel.com
State New
Headers show
Series Add iommufd nesting (part 2/2) | expand

Commit Message

Yi Liu Dec. 21, 2023, 3:39 p.m. UTC
In nested translation, the stage-1 page table is user-managed but cached
by the IOMMU hardware, so an update on present page table entries in the
stage-1 page table should be followed with a cache invalidation.

Add an IOMMU_HWPT_INVALIDATE ioctl to support such a cache invalidation.
It takes hwpt_id to specify the iommu_domain, and a multi-entry array to
support multiple invalidation requests in one ioctl.

This also adds the cache invalidation data structure for Intel VT-d to have
a complete story. Intel iommu driver support will be added in later patch.

Co-developed-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
Signed-off-by: Yi Liu <yi.l.liu@intel.com>
---
 drivers/iommu/iommufd/hw_pagetable.c    |  36 +++++++++
 drivers/iommu/iommufd/iommufd_private.h |  10 +++
 drivers/iommu/iommufd/main.c            |   3 +
 include/uapi/linux/iommufd.h            | 100 ++++++++++++++++++++++++
 4 files changed, 149 insertions(+)

Comments

Tian, Kevin Dec. 22, 2023, 3:19 a.m. UTC | #1
> From: Liu, Yi L <yi.l.liu@intel.com>
> Sent: Thursday, December 21, 2023 11:40 PM
> +
> +int iommufd_hwpt_invalidate(struct iommufd_ucmd *ucmd)
> +{
> +	struct iommu_hwpt_invalidate *cmd = ucmd->cmd;
> +	struct iommu_user_data_array data_array = {
> +		.type = cmd->req_type,
> +		.uptr = u64_to_user_ptr(cmd->reqs_uptr),
> +		.entry_len = cmd->req_len,
> +		.entry_num = cmd->req_num,
> +	};
> +	struct iommufd_hw_pagetable *hwpt;
> +	u32 done_num = 0;
> +	int rc;
> +
> +	if (cmd->req_num && (!cmd->reqs_uptr || !cmd->req_len)) {
> +		rc = -EINVAL;
> +		goto out;
> +	}

miss a check on the __reserved field.

> @@ -323,6 +323,7 @@ union ucmd_buffer {
>  	struct iommu_hwpt_alloc hwpt;
>  	struct iommu_hwpt_get_dirty_bitmap get_dirty_bitmap;
>  	struct iommu_hwpt_set_dirty_tracking set_dirty_tracking;
> +	struct iommu_hwpt_invalidate cache;

this should be in alphabetic order. I gave this comment in v6 too:

https://lore.kernel.org/linux-iommu/BN9PR11MB5276D8406BF08B853329288C8CB4A@BN9PR11MB5276.namprd11.prod.outlook.com/

> +/**
> + * enum iommu_hwpt_invalidate_data_type - IOMMU HWPT Cache
> Invalidation
> + *                                        Data Type
> + * @IOMMU_HWPT_INVALIDATE_DATA_VTD_S1: Invalidation data for
> VTD_S1
> + */
> +enum iommu_hwpt_invalidate_data_type {
> +	IOMMU_HWPT_INVALIDATE_DATA_VTD_S1,
> +};

Defining DATA_VTD_S1 at this point is fine, if there is no usage on
DATA_NONE. But following vtd specific definitions should be moved
to the later vtd specific patches. they are not used by the common
code anyway.

> +
> +/**
> + * enum iommu_hwpt_vtd_s1_invalidate_flags - Flags for Intel VT-d
> + *                                           stage-1 cache invalidation
> + * @IOMMU_VTD_INV_FLAGS_LEAF: The LEAF flag indicates whether only
> the
> + *                            leaf PTE caching needs to be invalidated
> + *                            and other paging structure caches can be
> + *                            preserved.

"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 - Result of invalidation

"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 addresses to be invalidated. It needs
> + *        to be 4KB aligned.

'of the range'

> + * @npages: Number of contiguous 4K pages to be invalidated.
> + * @flags: Combination of enum iommu_hwpt_vtd_s1_invalidate_flags
> + * @inv_error: One of enum iommu_hwpt_vtd_s1_invalidate_error

'@hw_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.

here should clarify that the invalidation applies to device TLB automatically
for VT-d.

> + *
> + * @inv_error is meaningful only if the request is handled by kernel. This
> + * can be known by checking struct iommu_hwpt_invalidate::req_num
> output.
> + * @inv_error only covers the errors detected by hardware after submitting
> the
> + * invalidation. The software detected errors would go through the normal
> + * ioctl errno.
> + */
> +struct iommu_hwpt_vtd_s1_invalidate {
> +	__aligned_u64 addr;
> +	__aligned_u64 npages;
> +	__u32 flags;
> +	__u32 inv_error;
> +};
> +
> +/**
> + * struct iommu_hwpt_invalidate - ioctl(IOMMU_HWPT_INVALIDATE)
> + * @size: sizeof(struct iommu_hwpt_invalidate)
> + * @hwpt_id: HWPT ID of a nested HWPT for cache invalidation
> + * @reqs_uptr: User pointer to an array having @req_num of cache
> invalidation
> + *             requests. The request entries in the array are of fixed width
> + *             @req_len, and contain a user data structure for invalidation
> + *             request specific to the given hardware page table.

Just:

'User pointer to an array of driver-specific cache invalidation requests'

> + * @req_type: One of enum iommu_hwpt_invalidate_data_type, defining
> the data
> + *            type of all the entries in the invalidation request array. It
> + *            should be a type supported by the hwpt pointed by @hwpt_id.
> + * @req_len: Length (in bytes) of a request entry in the request array
> + * @req_num: Input the number of cache invalidation requests in the array.
> + *           Output the number of requests successfully handled by kernel.
> + * @__reserved: Must be 0.
> + *
> + * Invalidate the iommu cache for user-managed page table. Modifications
> on a
> + * user-managed page table should be followed by this operation to sync
> cache.
> + * Each ioctl can support one or more cache invalidation requests in the
> array
> + * that has a total size of @req_len * @req_num.
> + *
> + * An empty invalidation request array by setting @req_num==0 is allowed,
> and
> + * @req_len and @reqs_uptr would be ignored in this case. This can be
> used to
> + * check if the given @req_type is supported or not by kernel.
> + */
> +struct iommu_hwpt_invalidate {
> +	__u32 size;
> +	__u32 hwpt_id;
> +	__aligned_u64 reqs_uptr;
> +	__u32 req_type;
> +	__u32 req_len;
> +	__u32 req_num;
> +	__u32 __reserved;
> +};
> +#define IOMMU_HWPT_INVALIDATE _IO(IOMMUFD_TYPE,
> IOMMUFD_CMD_HWPT_INVALIDATE)
>  #endif
> --
> 2.34.1
Yi Liu Dec. 26, 2023, 4 a.m. UTC | #2
On 2023/12/22 11:19, Tian, Kevin wrote:
>> From: Liu, Yi L <yi.l.liu@intel.com>
>> Sent: Thursday, December 21, 2023 11:40 PM
>> +
>> +int iommufd_hwpt_invalidate(struct iommufd_ucmd *ucmd)
>> +{
>> +	struct iommu_hwpt_invalidate *cmd = ucmd->cmd;
>> +	struct iommu_user_data_array data_array = {
>> +		.type = cmd->req_type,
>> +		.uptr = u64_to_user_ptr(cmd->reqs_uptr),
>> +		.entry_len = cmd->req_len,
>> +		.entry_num = cmd->req_num,
>> +	};
>> +	struct iommufd_hw_pagetable *hwpt;
>> +	u32 done_num = 0;
>> +	int rc;
>> +
>> +	if (cmd->req_num && (!cmd->reqs_uptr || !cmd->req_len)) {
>> +		rc = -EINVAL;
>> +		goto out;
>> +	}
> 
> miss a check on the __reserved field.

done.

> 
>> @@ -323,6 +323,7 @@ union ucmd_buffer {
>>   	struct iommu_hwpt_alloc hwpt;
>>   	struct iommu_hwpt_get_dirty_bitmap get_dirty_bitmap;
>>   	struct iommu_hwpt_set_dirty_tracking set_dirty_tracking;
>> +	struct iommu_hwpt_invalidate cache;
> 
> this should be in alphabetic order. I gave this comment in v6 too:
> 
> https://lore.kernel.org/linux-iommu/BN9PR11MB5276D8406BF08B853329288C8CB4A@BN9PR11MB5276.namprd11.prod.outlook.com/

oops, I did miss it. sigh, I paid too much attention to the error code
discussion in the end. :( I've revisited the comments and should have
done now.

>> +/**
>> + * enum iommu_hwpt_invalidate_data_type - IOMMU HWPT Cache
>> Invalidation
>> + *                                        Data Type
>> + * @IOMMU_HWPT_INVALIDATE_DATA_VTD_S1: Invalidation data for
>> VTD_S1
>> + */
>> +enum iommu_hwpt_invalidate_data_type {
>> +	IOMMU_HWPT_INVALIDATE_DATA_VTD_S1,
>> +};
> 
> Defining DATA_VTD_S1 at this point is fine, if there is no usage on
> DATA_NONE. But following vtd specific definitions should be moved
> to the later vtd specific patches. they are not used by the common
> code anyway.

sure.

>> +
>> +/**
>> + * enum iommu_hwpt_vtd_s1_invalidate_flags - Flags for Intel VT-d
>> + *                                           stage-1 cache invalidation
>> + * @IOMMU_VTD_INV_FLAGS_LEAF: The LEAF flag indicates whether only
>> the
>> + *                            leaf PTE caching needs to be invalidated
>> + *                            and other paging structure caches can be
>> + *                            preserved.
> 
> "indicates whether the invalidation applies to all-levels page structure
> cache or just the leaf PTE cache"

done.

>> + */
>> +enum iommu_hwpt_vtd_s1_invalidate_flags {
>> +	IOMMU_VTD_INV_FLAGS_LEAF = 1 << 0,
>> +};
>> +
>> +/**
>> + * enum iommu_hwpt_vtd_s1_invalidate_error - Result of invalidation
> 
> "hardware error of invalidation"

done.

> 
>> + * @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 addresses to be invalidated. It needs
>> + *        to be 4KB aligned.
> 
> 'of the range'

done.

> 
>> + * @npages: Number of contiguous 4K pages to be invalidated.
>> + * @flags: Combination of enum iommu_hwpt_vtd_s1_invalidate_flags
>> + * @inv_error: One of enum iommu_hwpt_vtd_s1_invalidate_error
> 
> '@hw_error'

done.

>> + *
>> + * 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.
> 
> here should clarify that the invalidation applies to device TLB automatically
> for VT-d.

done.

>> + *
>> + * @inv_error is meaningful only if the request is handled by kernel. This
>> + * can be known by checking struct iommu_hwpt_invalidate::req_num
>> output.
>> + * @inv_error only covers the errors detected by hardware after submitting
>> the
>> + * invalidation. The software detected errors would go through the normal
>> + * ioctl errno.
>> + */
>> +struct iommu_hwpt_vtd_s1_invalidate {
>> +	__aligned_u64 addr;
>> +	__aligned_u64 npages;
>> +	__u32 flags;
>> +	__u32 inv_error;
>> +};
>> +
>> +/**
>> + * struct iommu_hwpt_invalidate - ioctl(IOMMU_HWPT_INVALIDATE)
>> + * @size: sizeof(struct iommu_hwpt_invalidate)
>> + * @hwpt_id: HWPT ID of a nested HWPT for cache invalidation
>> + * @reqs_uptr: User pointer to an array having @req_num of cache
>> invalidation
>> + *             requests. The request entries in the array are of fixed width
>> + *             @req_len, and contain a user data structure for invalidation
>> + *             request specific to the given hardware page table.
> 
> Just:
> 
> 'User pointer to an array of driver-specific cache invalidation requests'

done.

>> + * @req_type: One of enum iommu_hwpt_invalidate_data_type, defining
>> the data
>> + *            type of all the entries in the invalidation request array. It
>> + *            should be a type supported by the hwpt pointed by @hwpt_id.
>> + * @req_len: Length (in bytes) of a request entry in the request array
>> + * @req_num: Input the number of cache invalidation requests in the array.

s/req_len/entry_len, s/req_num/entry_num per the comments in last version.

>> + *           Output the number of requests successfully handled by kernel.
>> + * @__reserved: Must be 0.
>> + *
>> + * Invalidate the iommu cache for user-managed page table. Modifications
>> on a
>> + * user-managed page table should be followed by this operation to sync
>> cache.
>> + * Each ioctl can support one or more cache invalidation requests in the
>> array
>> + * that has a total size of @req_len * @req_num.
>> + *
>> + * An empty invalidation request array by setting @req_num==0 is allowed,
>> and
>> + * @req_len and @reqs_uptr would be ignored in this case. This can be
>> used to
>> + * check if the given @req_type is supported or not by kernel.
>> + */
>> +struct iommu_hwpt_invalidate {
>> +	__u32 size;
>> +	__u32 hwpt_id;
>> +	__aligned_u64 reqs_uptr;
>> +	__u32 req_type;
>> +	__u32 req_len;
>> +	__u32 req_num;
>> +	__u32 __reserved;
>> +};
>> +#define IOMMU_HWPT_INVALIDATE _IO(IOMMUFD_TYPE,
>> IOMMUFD_CMD_HWPT_INVALIDATE)
>>   #endif
>> --
>> 2.34.1
>
diff mbox series

Patch

diff --git a/drivers/iommu/iommufd/hw_pagetable.c b/drivers/iommu/iommufd/hw_pagetable.c
index cbb5df0a6c32..6389a9809c7b 100644
--- a/drivers/iommu/iommufd/hw_pagetable.c
+++ b/drivers/iommu/iommufd/hw_pagetable.c
@@ -371,3 +371,39 @@  int iommufd_hwpt_get_dirty_bitmap(struct iommufd_ucmd *ucmd)
 	iommufd_put_object(ucmd->ictx, &hwpt_paging->common.obj);
 	return rc;
 }
+
+int iommufd_hwpt_invalidate(struct iommufd_ucmd *ucmd)
+{
+	struct iommu_hwpt_invalidate *cmd = ucmd->cmd;
+	struct iommu_user_data_array data_array = {
+		.type = cmd->req_type,
+		.uptr = u64_to_user_ptr(cmd->reqs_uptr),
+		.entry_len = cmd->req_len,
+		.entry_num = cmd->req_num,
+	};
+	struct iommufd_hw_pagetable *hwpt;
+	u32 done_num = 0;
+	int rc;
+
+	if (cmd->req_num && (!cmd->reqs_uptr || !cmd->req_len)) {
+		rc = -EINVAL;
+		goto out;
+	}
+
+	hwpt = iommufd_get_hwpt_nested(ucmd, cmd->hwpt_id);
+	if (IS_ERR(hwpt)) {
+		rc = PTR_ERR(hwpt);
+		goto out;
+	}
+
+	rc = hwpt->domain->ops->cache_invalidate_user(hwpt->domain,
+						      &data_array);
+	done_num = data_array.entry_num;
+
+	iommufd_put_object(ucmd->ictx, &hwpt->obj);
+out:
+	cmd->req_num = done_num;
+	if (iommufd_ucmd_respond(ucmd, sizeof(*cmd)))
+		return -EFAULT;
+	return rc;
+}
diff --git a/drivers/iommu/iommufd/iommufd_private.h b/drivers/iommu/iommufd/iommufd_private.h
index abae041e256f..991f864d1f9b 100644
--- a/drivers/iommu/iommufd/iommufd_private.h
+++ b/drivers/iommu/iommufd/iommufd_private.h
@@ -328,6 +328,15 @@  iommufd_get_hwpt_paging(struct iommufd_ucmd *ucmd, u32 id)
 					       IOMMUFD_OBJ_HWPT_PAGING),
 			    struct iommufd_hwpt_paging, common.obj);
 }
+
+static inline struct iommufd_hw_pagetable *
+iommufd_get_hwpt_nested(struct iommufd_ucmd *ucmd, u32 id)
+{
+	return container_of(iommufd_get_object(ucmd->ictx, id,
+					       IOMMUFD_OBJ_HWPT_NESTED),
+			    struct iommufd_hw_pagetable, obj);
+}
+
 int iommufd_hwpt_set_dirty_tracking(struct iommufd_ucmd *ucmd);
 int iommufd_hwpt_get_dirty_bitmap(struct iommufd_ucmd *ucmd);
 
@@ -345,6 +354,7 @@  void iommufd_hwpt_paging_abort(struct iommufd_object *obj);
 void iommufd_hwpt_nested_destroy(struct iommufd_object *obj);
 void iommufd_hwpt_nested_abort(struct iommufd_object *obj);
 int iommufd_hwpt_alloc(struct iommufd_ucmd *ucmd);
+int iommufd_hwpt_invalidate(struct iommufd_ucmd *ucmd);
 
 static inline void iommufd_hw_pagetable_put(struct iommufd_ctx *ictx,
 					    struct iommufd_hw_pagetable *hwpt)
diff --git a/drivers/iommu/iommufd/main.c b/drivers/iommu/iommufd/main.c
index c9091e46d208..e4f6dfc3474f 100644
--- a/drivers/iommu/iommufd/main.c
+++ b/drivers/iommu/iommufd/main.c
@@ -323,6 +323,7 @@  union ucmd_buffer {
 	struct iommu_hwpt_alloc hwpt;
 	struct iommu_hwpt_get_dirty_bitmap get_dirty_bitmap;
 	struct iommu_hwpt_set_dirty_tracking set_dirty_tracking;
+	struct iommu_hwpt_invalidate cache;
 	struct iommu_ioas_alloc alloc;
 	struct iommu_ioas_allow_iovas allow_iovas;
 	struct iommu_ioas_copy ioas_copy;
@@ -362,6 +363,8 @@  static const struct iommufd_ioctl_op iommufd_ioctl_ops[] = {
 		 struct iommu_hwpt_get_dirty_bitmap, data),
 	IOCTL_OP(IOMMU_HWPT_SET_DIRTY_TRACKING, iommufd_hwpt_set_dirty_tracking,
 		 struct iommu_hwpt_set_dirty_tracking, __reserved),
+	IOCTL_OP(IOMMU_HWPT_INVALIDATE, iommufd_hwpt_invalidate,
+		 struct iommu_hwpt_invalidate, __reserved),
 	IOCTL_OP(IOMMU_IOAS_ALLOC, iommufd_ioas_alloc_ioctl,
 		 struct iommu_ioas_alloc, out_ioas_id),
 	IOCTL_OP(IOMMU_IOAS_ALLOW_IOVAS, iommufd_ioas_allow_iovas,
diff --git a/include/uapi/linux/iommufd.h b/include/uapi/linux/iommufd.h
index 0b2bc6252e2c..e501ef4f7ec1 100644
--- a/include/uapi/linux/iommufd.h
+++ b/include/uapi/linux/iommufd.h
@@ -49,6 +49,7 @@  enum {
 	IOMMUFD_CMD_GET_HW_INFO,
 	IOMMUFD_CMD_HWPT_SET_DIRTY_TRACKING,
 	IOMMUFD_CMD_HWPT_GET_DIRTY_BITMAP,
+	IOMMUFD_CMD_HWPT_INVALIDATE,
 };
 
 /**
@@ -613,4 +614,103 @@  struct iommu_hwpt_get_dirty_bitmap {
 #define IOMMU_HWPT_GET_DIRTY_BITMAP _IO(IOMMUFD_TYPE, \
 					IOMMUFD_CMD_HWPT_GET_DIRTY_BITMAP)
 
+/**
+ * enum iommu_hwpt_invalidate_data_type - IOMMU HWPT Cache Invalidation
+ *                                        Data Type
+ * @IOMMU_HWPT_INVALIDATE_DATA_VTD_S1: Invalidation data for VTD_S1
+ */
+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: The LEAF flag indicates whether only the
+ *                            leaf PTE caching needs to be invalidated
+ *                            and other paging structure caches can be
+ *                            preserved.
+ */
+enum iommu_hwpt_vtd_s1_invalidate_flags {
+	IOMMU_VTD_INV_FLAGS_LEAF = 1 << 0,
+};
+
+/**
+ * enum iommu_hwpt_vtd_s1_invalidate_error - Result 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 addresses 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
+ * @inv_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.
+ *
+ * @inv_error is meaningful only if the request is handled by kernel. This
+ * can be known by checking struct iommu_hwpt_invalidate::req_num output.
+ * @inv_error only covers the errors detected by hardware after submitting the
+ * invalidation. The software detected errors would go through the normal
+ * ioctl errno.
+ */
+struct iommu_hwpt_vtd_s1_invalidate {
+	__aligned_u64 addr;
+	__aligned_u64 npages;
+	__u32 flags;
+	__u32 inv_error;
+};
+
+/**
+ * struct iommu_hwpt_invalidate - ioctl(IOMMU_HWPT_INVALIDATE)
+ * @size: sizeof(struct iommu_hwpt_invalidate)
+ * @hwpt_id: HWPT ID of a nested HWPT for cache invalidation
+ * @reqs_uptr: User pointer to an array having @req_num of cache invalidation
+ *             requests. The request entries in the array are of fixed width
+ *             @req_len, and contain a user data structure for invalidation
+ *             request specific to the given hardware page table.
+ * @req_type: One of enum iommu_hwpt_invalidate_data_type, defining the data
+ *            type of all the entries in the invalidation request array. It
+ *            should be a type supported by the hwpt pointed by @hwpt_id.
+ * @req_len: Length (in bytes) of a request entry in the request array
+ * @req_num: Input the number of cache invalidation requests in the array.
+ *           Output the number of requests successfully handled by kernel.
+ * @__reserved: Must be 0.
+ *
+ * Invalidate the iommu cache for user-managed page table. Modifications on a
+ * user-managed page table should be followed by this operation to sync cache.
+ * Each ioctl can support one or more cache invalidation requests in the array
+ * that has a total size of @req_len * @req_num.
+ *
+ * An empty invalidation request array by setting @req_num==0 is allowed, and
+ * @req_len and @reqs_uptr would be ignored in this case. This can be used to
+ * check if the given @req_type is supported or not by kernel.
+ */
+struct iommu_hwpt_invalidate {
+	__u32 size;
+	__u32 hwpt_id;
+	__aligned_u64 reqs_uptr;
+	__u32 req_type;
+	__u32 req_len;
+	__u32 req_num;
+	__u32 __reserved;
+};
+#define IOMMU_HWPT_INVALIDATE _IO(IOMMUFD_TYPE, IOMMUFD_CMD_HWPT_INVALIDATE)
 #endif