[PATCH v8 08/14] iommufd/selftest: Require vdev_id when attaching to a nested domain

[Nicolin Chen <nicolinc@nvidia.com>]

When attaching a device to a vIOMMU-based nested domain, vdev_id must be
present. Add a piece of code hard-requesting it, preparing for a vEVENTQ
support in the following patch. Then, update the TEST_F.

A HWPT-based nested domain will return a NULL new_viommu, thus no such a
vDEVICE requirement.

Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Nicolin Chen <nicolinc@nvidia.com>
---
 drivers/iommu/iommufd/selftest.c        | 24 ++++++++++++++++++++++++
 tools/testing/selftests/iommu/iommufd.c |  5 +++++
 2 files changed, 29 insertions(+)

diff --git a/drivers/iommu/iommufd/selftest.c b/drivers/iommu/iommufd/selftest.c
index d40deb0a4f06..ba84bacbce2e 100644
--- a/drivers/iommu/iommufd/selftest.c
+++ b/drivers/iommu/iommufd/selftest.c
@@ -161,7 +161,10 @@ enum selftest_obj_type {
 
 struct mock_dev {
 	struct device dev;
+	struct mock_viommu *viommu;
+	struct rw_semaphore viommu_rwsem;
 	unsigned long flags;
+	unsigned long vdev_id;
 	int id;
 	u32 cache[MOCK_DEV_CACHE_NUM];
 };
@@ -193,10 +196,30 @@ static int mock_domain_nop_attach(struct iommu_domain *domain,
 				  struct device *dev)
 {
 	struct mock_dev *mdev = to_mock_dev(dev);
+	struct mock_viommu *new_viommu = NULL;
+	unsigned long vdev_id = 0;
+	int rc;
 
 	if (domain->dirty_ops && (mdev->flags & MOCK_FLAGS_DEVICE_NO_DIRTY))
 		return -EINVAL;
 
+	iommu_group_mutex_assert(dev);
+	if (domain->type == IOMMU_DOMAIN_NESTED) {
+		new_viommu = to_mock_nested(domain)->mock_viommu;
+		if (new_viommu) {
+			rc = iommufd_viommu_get_vdev_id(&new_viommu->core, dev,
+							&vdev_id);
+			if (rc)
+				return rc;
+		}
+	}
+	if (new_viommu != mdev->viommu) {
+		down_write(&mdev->viommu_rwsem);
+		mdev->viommu = new_viommu;
+		mdev->vdev_id = vdev_id;
+		up_write(&mdev->viommu_rwsem);
+	}
+
 	return 0;
 }
 
@@ -850,6 +873,7 @@ static struct mock_dev *mock_dev_create(unsigned long dev_flags)
 	if (!mdev)
 		return ERR_PTR(-ENOMEM);
 
+	init_rwsem(&mdev->viommu_rwsem);
 	device_initialize(&mdev->dev);
 	mdev->flags = dev_flags;
 	mdev->dev.release = mock_dev_release;
diff --git a/tools/testing/selftests/iommu/iommufd.c b/tools/testing/selftests/iommu/iommufd.c
index a1b2b657999d..212e5d62e13d 100644
--- a/tools/testing/selftests/iommu/iommufd.c
+++ b/tools/testing/selftests/iommu/iommufd.c
@@ -2736,6 +2736,7 @@ TEST_F(iommufd_viommu, viommu_alloc_nested_iopf)
 	uint32_t iopf_hwpt_id;
 	uint32_t fault_id;
 	uint32_t fault_fd;
+	uint32_t vdev_id;
 
 	if (self->device_id) {
 		test_ioctl_fault_alloc(&fault_id, &fault_fd);
@@ -2752,6 +2753,10 @@ TEST_F(iommufd_viommu, viommu_alloc_nested_iopf)
 			&iopf_hwpt_id, IOMMU_HWPT_DATA_SELFTEST, &data,
 			sizeof(data));
 
+		/* Must allocate vdevice before attaching to a nested hwpt */
+		test_err_mock_domain_replace(ENOENT, self->stdev_id,
+					     iopf_hwpt_id);
+		test_cmd_vdevice_alloc(viommu_id, dev_id, 0x99, &vdev_id);
 		test_cmd_mock_domain_replace(self->stdev_id, iopf_hwpt_id);
 		EXPECT_ERRNO(EBUSY,
 			     _test_ioctl_destroy(self->fd, iopf_hwpt_id));
-- 
2.43.0