[Intel-gfx] [PATCH 16/16] drm/i915: Add selftests for object allocation, phys

[Chris Wilson]

The phys object is a rarely used device (only very old machines require
a chunk of physically contiguous pages for a few hardware interactions).
As such, it is not exercised by CI and to combat that we want to add a
test that exercises the phys object on all platforms.

Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
---
 drivers/gpu/drm/i915/i915_gem.c            | 168 +++++++++++++++++++++++++++++
 drivers/gpu/drm/i915/i915_mock_selftests.h |   1 +
 2 files changed, 169 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c
index 9794dd655877..1ab5fdae2d47 100644
--- a/drivers/gpu/drm/i915/i915_gem.c
+++ b/drivers/gpu/drm/i915/i915_gem.c
@@ -4949,3 +4949,171 @@ i915_gem_object_get_dma_address(struct drm_i915_gem_object *obj,
 	sg = i915_gem_object_get_sg(obj, n, &offset);
 	return sg_dma_address(sg) + (offset << PAGE_SHIFT);
 }
+
+#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST)
+#include <linux/pm_runtime.h>
+
+#include "i915_selftest.h"
+
+static struct drm_driver mock_driver = {
+	.name = "mock",
+	.driver_features = DRIVER_GEM,
+
+	.gem_close_object = i915_gem_close_object,
+	.gem_free_object_unlocked = i915_gem_free_object,
+};
+
+struct mock_object {
+	struct drm_i915_gem_object base;
+};
+
+static void release_dev(struct device *dev)
+{
+	struct pci_dev *pdev = to_pci_dev(dev);
+
+	kfree(pdev);
+}
+
+static struct drm_i915_private *mock_gem_device(void)
+{
+	struct drm_i915_private *i915;
+	struct pci_dev *pdev;
+	int err;
+
+	i915 = kzalloc(sizeof(*i915), GFP_TEMPORARY);
+	if (!i915)
+		return NULL;
+
+	pdev = kzalloc(sizeof(*pdev), GFP_TEMPORARY);
+	if (!pdev) {
+		kfree(i915);
+		return NULL;
+	}
+
+	device_initialize(&pdev->dev);
+	pdev->dev.release = release_dev;
+	dev_set_name(&pdev->dev, "mock");
+	dma_coerce_mask_and_coherent(&pdev->dev, DMA_BIT_MASK(32));
+
+	pm_runtime_dont_use_autosuspend(&pdev->dev);
+	pm_runtime_get_sync(&pdev->dev);
+	pci_set_drvdata(pdev, i915);
+
+	err = drm_dev_init(&i915->drm, &mock_driver, &pdev->dev);
+	if (err) {
+		pr_err("Failed to initialise mock GEM device: err=%d\n", err);
+		put_device(&pdev->dev);
+		kfree(i915);
+		return NULL;
+	}
+	i915->drm.pdev = pdev;
+	i915->drm.dev_private = i915;
+
+	mkwrite_device_info(i915)->gen = -1;
+
+	spin_lock_init(&i915->mm.object_stat_lock);
+
+	INIT_WORK(&i915->mm.free_work, __i915_gem_free_work);
+	init_llist_head(&i915->mm.free_list);
+
+	i915->objects = KMEM_CACHE(mock_object, SLAB_HWCACHE_ALIGN);
+	if (!i915->objects)
+		goto err_device;
+
+	return i915;
+
+err_device:
+	kfree(i915);
+	return NULL;
+}
+
+static void mock_device_free(struct drm_i915_private *i915)
+{
+	struct pci_dev *pdev = i915->drm.pdev;
+
+	rcu_barrier();
+	while (flush_work(&i915->mm.free_work))
+		rcu_barrier();
+
+	drm_dev_unref(&i915->drm);
+	put_device(&pdev->dev);
+}
+
+static int igt_gem_object(void *ignore)
+{
+	struct drm_i915_gem_object *obj;
+	struct drm_i915_private *i915;
+	int err = -ENOMEM;
+
+	i915 = mock_gem_device();
+	if (!i915)
+		goto out;
+
+	obj = i915_gem_object_create(i915, 4096);
+	if (IS_ERR(obj)) {
+		err = PTR_ERR(obj);
+		pr_err("i915_gem_object_create failed, err=%d\n", err);
+		goto out_device;
+	}
+
+	err = 0;
+	i915_gem_object_put(obj);
+out_device:
+	mock_device_free(i915);
+out:
+	return err;
+}
+
+static int igt_phys_object(void *ignore)
+{
+	struct drm_i915_gem_object *obj;
+	struct drm_i915_private *i915;
+	int err = -ENOMEM;
+
+	i915 = mock_gem_device();
+	if (!i915)
+		goto out;
+
+	obj = i915_gem_object_create(i915, 4096);
+	if (IS_ERR(obj)) {
+		err = PTR_ERR(obj);
+		pr_err("i915_gem_object_create failed, err=%d\n", err);
+		goto out_device;
+	}
+
+	err = -EINVAL;
+	mutex_lock(&i915->drm.struct_mutex);
+	err = i915_gem_object_attach_phys(obj, PAGE_SIZE);
+	mutex_unlock(&i915->drm.struct_mutex);
+	if (err) {
+		pr_err("i915_gem_object_attach_phys failed, err=%d\n", err);
+		goto err;
+	}
+
+	if (obj->ops != &i915_gem_phys_ops) {
+		pr_err("i915_gem_object_attach_phys did not create a phys object\n");
+		goto err;
+	}
+
+	/* Make the object work during teardown */
+	obj->mm.dirty = true;
+
+	err = 0;
+err:
+	i915_gem_object_put(obj);
+out_device:
+	mock_device_free(i915);
+out:
+	return err;
+}
+
+int i915_gem_object_selftests(void)
+{
+	static const struct i915_subtest tests[] = {
+		SUBTEST(igt_gem_object),
+		SUBTEST(igt_phys_object),
+	};
+
+	return i915_subtests(tests, NULL);
+}
+#endif
diff --git a/drivers/gpu/drm/i915/i915_mock_selftests.h b/drivers/gpu/drm/i915/i915_mock_selftests.h
index 9ff379b18c20..34f32f777b34 100644
--- a/drivers/gpu/drm/i915/i915_mock_selftests.h
+++ b/drivers/gpu/drm/i915/i915_mock_selftests.h
@@ -8,6 +8,7 @@
  *
  * Tests are executed in reverse order by igt/drv_selftest
  */
+selftest(objects, i915_gem_object_selftests)
 selftest(requests, i915_gem_request_selftest)
 selftest(breadcrumbs, intel_breadcrumbs_selftest)
 selftest(sanitycheck, i915_mock_sanitycheck) /* keep last */
-- 
2.11.0