Commit 54ce69e3 authored by Nicolin Chen's avatar Nicolin Chen Committed by Jason Gunthorpe
Browse files

iommufd: Allow hwpt_id to carry viommu_id for IOMMU_HWPT_INVALIDATE 

With a vIOMMU object, use space can flush any IOMMU related cache that can
be directed via a vIOMMU object. It is similar to the IOMMU_HWPT_INVALIDATE
uAPI, but can cover a wider range than IOTLB, e.g. device/desciprtor cache.

Allow hwpt_id of the iommu_hwpt_invalidate structure to carry a viommu_id,
and reuse the IOMMU_HWPT_INVALIDATE uAPI for vIOMMU invalidations. Drivers
can define different structures for vIOMMU invalidations v.s. HWPT ones.

Since both the HWPT-based and vIOMMU-based invalidation pathways check own
cache invalidation op, remove the WARN_ON_ONCE in the allocator.

Update the uAPI, kdoc, and selftest case accordingly.

Link: https://patch.msgid.link/r/b411e2245e303b8a964f39f49453a5dff280968f.1730836308.git.nicolinc@nvidia.com


Reviewed-by: default avatarJason Gunthorpe <jgg@nvidia.com>
Reviewed-by: default avatarKevin Tian <kevin.tian@intel.com>
Signed-off-by: default avatarNicolin Chen <nicolinc@nvidia.com>
Signed-off-by: default avatarJason Gunthorpe <jgg@nvidia.com>
parent 67db79dc

drivers/iommu/iommufd/hw_pagetable.c

+31 −9
Original line number Diff line number Diff line
@@ -251,8 +251,7 @@ iommufd_hwpt_nested_alloc(struct iommufd_ctx *ictx, 
	}

	hwpt->domain->owner = ops;



	if (WARN_ON_ONCE(hwpt->domain->type != IOMMU_DOMAIN_NESTED ||

			 !hwpt->domain->ops->cache_invalidate_user)) {

	if (WARN_ON_ONCE(hwpt->domain->type != IOMMU_DOMAIN_NESTED)) {

		rc = -EINVAL;

		goto out_abort;

	}
@@ -483,7 +482,7 @@ int iommufd_hwpt_invalidate(struct iommufd_ucmd *ucmd) 
		.entry_len = cmd->entry_len,

		.entry_num = cmd->entry_num,

	};

	struct iommufd_hw_pagetable *hwpt;

	struct iommufd_object *pt_obj;

	u32 done_num = 0;

	int rc;
@@ -497,17 +496,40 @@ int iommufd_hwpt_invalidate(struct iommufd_ucmd *ucmd) 
		goto out;

	}



	hwpt = iommufd_get_hwpt_nested(ucmd, cmd->hwpt_id);

	if (IS_ERR(hwpt)) {

		rc = PTR_ERR(hwpt);

	pt_obj = iommufd_get_object(ucmd->ictx, cmd->hwpt_id, IOMMUFD_OBJ_ANY);

	if (IS_ERR(pt_obj)) {

		rc = PTR_ERR(pt_obj);

		goto out;

	}

	if (pt_obj->type == IOMMUFD_OBJ_HWPT_NESTED) {

		struct iommufd_hw_pagetable *hwpt =

			container_of(pt_obj, struct iommufd_hw_pagetable, obj);



		if (!hwpt->domain->ops ||

		    !hwpt->domain->ops->cache_invalidate_user) {

			rc = -EOPNOTSUPP;

			goto out_put_pt;

		}

		rc = hwpt->domain->ops->cache_invalidate_user(hwpt->domain,

							      &data_array);

	} else if (pt_obj->type == IOMMUFD_OBJ_VIOMMU) {

		struct iommufd_viommu *viommu =

			container_of(pt_obj, struct iommufd_viommu, obj);



		if (!viommu->ops || !viommu->ops->cache_invalidate) {

			rc = -EOPNOTSUPP;

			goto out_put_pt;

		}

		rc = viommu->ops->cache_invalidate(viommu, &data_array);

	} else {

		rc = -EINVAL;

		goto out_put_pt;

	}



	done_num = data_array.entry_num;



	iommufd_put_object(ucmd->ictx, &hwpt->obj);

out_put_pt:

	iommufd_put_object(ucmd->ictx, pt_obj);

out:

	cmd->entry_num = done_num;

	if (iommufd_ucmd_respond(ucmd, sizeof(*cmd)))

include/uapi/linux/iommufd.h

+6 −3
Original line number Diff line number Diff line
@@ -700,7 +700,7 @@ struct iommu_hwpt_vtd_s1_invalidate { 
/**

 * struct iommu_hwpt_invalidate - ioctl(IOMMU_HWPT_INVALIDATE)

 * @size: sizeof(struct iommu_hwpt_invalidate)

 * @hwpt_id: ID of a nested HWPT for cache invalidation

 * @hwpt_id: ID of a nested HWPT or a vIOMMU, for cache invalidation

 * @data_uptr: User pointer to an array of driver-specific cache invalidation

 *             data.

 * @data_type: One of enum iommu_hwpt_invalidate_data_type, defining the data
@@ -711,8 +711,11 @@ struct iommu_hwpt_vtd_s1_invalidate { 
 *             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.

 * Invalidate iommu cache for user-managed page table or vIOMMU. Modifications

 * on a user-managed page table should be followed by this operation, if a HWPT

 * is passed in via @hwpt_id. Other caches, such as device cache or descriptor

 * cache can be flushed if a vIOMMU is passed in via the @hwpt_id field.

 *

 * Each ioctl can support one or more cache invalidation requests in the array

 * that has a total size of @entry_len * @entry_num.

 *

tools/testing/selftests/iommu/iommufd.c

+2 −2
Original line number Diff line number Diff line
@@ -367,9 +367,9 @@ TEST_F(iommufd_ioas, alloc_hwpt_nested) 
		EXPECT_ERRNO(EBUSY,

			     _test_ioctl_destroy(self->fd, parent_hwpt_id));



		/* hwpt_invalidate only supports a user-managed hwpt (nested) */

		/* hwpt_invalidate does not support a parent hwpt */

		num_inv = 1;

		test_err_hwpt_invalidate(ENOENT, parent_hwpt_id, inv_reqs,

		test_err_hwpt_invalidate(EINVAL, parent_hwpt_id, inv_reqs,

					 IOMMU_HWPT_INVALIDATE_DATA_SELFTEST,

					 sizeof(*inv_reqs), &num_inv);

		assert(!num_inv);