iommufd/selftest: Test IOMMU_HWPT_ALLOC_DIRTY_TRACKING

In order to selftest the iommu domain dirty enforcing implement the
mock_domain necessary support and add a new dev_flags to test that the
hwpt_alloc/attach_device fails as expected.

Expand the existing mock_domain fixture with a enforce_dirty test that
exercises the hwpt_alloc and device attachment.

Link: https://lore.kernel.org/r/20231024135109.73787-15-joao.m.martins@oracle.com
Signed-off-by: Joao Martins <joao.m.martins@oracle.com>
Reviewed-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

1 files changed, 36 insertions, 1 deletions

diff --git a/drivers/iommu/iommufd/selftest.c b/drivers/iommu/iommufd/selftest.c
index bd3704b28bfb..78362f2334f5 100644
--- a/drivers/iommu/iommufd/selftest.c
+++ b/drivers/iommu/iommufd/selftest.c
@@ -119,6 +119,11 @@ static void mock_domain_blocking_free(struct iommu_domain *domain)
 static int mock_domain_nop_attach(struct iommu_domain *domain,
 				  struct device *dev)
 {
+	struct mock_dev *mdev = container_of(dev, struct mock_dev, dev);
+
+	if (domain->dirty_ops && (mdev->flags & MOCK_FLAGS_DEVICE_NO_DIRTY))
+		return -EINVAL;
+
 	return 0;
 }
 
@@ -147,6 +152,25 @@ static void *mock_domain_hw_info(struct device *dev, u32 *length, u32 *type)
 	return info;
 }
 
+static int mock_domain_set_dirty_tracking(struct iommu_domain *domain,
+					  bool enable)
+{
+	return 0;
+}
+
+static int mock_domain_read_and_clear_dirty(struct iommu_domain *domain,
+					    unsigned long iova, size_t size,
+					    unsigned long flags,
+					    struct iommu_dirty_bitmap *dirty)
+{
+	return 0;
+}
+
+const struct iommu_dirty_ops dirty_ops = {
+	.set_dirty_tracking = mock_domain_set_dirty_tracking,
+	.read_and_clear_dirty = mock_domain_read_and_clear_dirty,
+};
+
 static const struct iommu_ops mock_ops;
 
 static struct iommu_domain *mock_domain_alloc(unsigned int iommu_domain_type)
@@ -174,12 +198,20 @@ static struct iommu_domain *mock_domain_alloc(unsigned int iommu_domain_type)
 static struct iommu_domain *
 mock_domain_alloc_user(struct device *dev, u32 flags)
 {
+	struct mock_dev *mdev = container_of(dev, struct mock_dev, dev);
 	struct iommu_domain *domain;
 
-	if (flags & (~IOMMU_HWPT_ALLOC_NEST_PARENT))
+	if (flags &
+	    (~(IOMMU_HWPT_ALLOC_NEST_PARENT | IOMMU_HWPT_ALLOC_DIRTY_TRACKING)))
+		return ERR_PTR(-EOPNOTSUPP);
+
+	if ((flags & IOMMU_HWPT_ALLOC_DIRTY_TRACKING) &&
+	    (mdev->flags & MOCK_FLAGS_DEVICE_NO_DIRTY))
 		return ERR_PTR(-EOPNOTSUPP);
 
 	domain = mock_domain_alloc(IOMMU_DOMAIN_UNMANAGED);
+	if (domain && !(mdev->flags & MOCK_FLAGS_DEVICE_NO_DIRTY))
+		domain->dirty_ops = &dirty_ops;
 	if (!domain)
 		domain = ERR_PTR(-ENOMEM);
 	return domain;
@@ -387,6 +419,9 @@ static struct mock_dev *mock_dev_create(unsigned long dev_flags)
 	struct mock_dev *mdev;
 	int rc;
 
+	if (dev_flags & ~(MOCK_FLAGS_DEVICE_NO_DIRTY))
+		return ERR_PTR(-EINVAL);
+
 	mdev = kzalloc(sizeof(*mdev), GFP_KERNEL);
 	if (!mdev)
 		return ERR_PTR(-ENOMEM);