drm/ttm/tests: Add tests for ttm_tt

Test initialization, creation and destruction of ttm_tt instances.
Export ttm_tt_destroy and ttm_tt_create symbols for testing purposes.
Signed-off-by: Karolina Stolarek <karolina.stolarek@intel.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Tested-by: Amaranath Somalapuram <Amaranath.Somalapuram@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/4459cb89c666bfa377753ae18d0c8917131638e8.1701257386.git.karolina.stolarek@intel.comSigned-off-by: Christian König <christian.koenig@amd.com>

drivers/gpu/drm/ttm/tests/Makefile

@@ -4,4 +4,5 @@ obj-$(CONFIG_DRM_TTM_KUNIT_TEST) += \
         ttm_device_test.o \
         ttm_pool_test.o \
         ttm_resource_test.o \
+        ttm_tt_test.o \
         ttm_kunit_helpers.o

drivers/gpu/drm/ttm/tests/ttm_kunit_helpers.c

@@ -2,9 +2,29 @@
 /*
  * Copyright © 2023 Intel Corporation
  */
+#include <drm/ttm/ttm_tt.h>
+
 #include "ttm_kunit_helpers.h"
 
+static struct ttm_tt *ttm_tt_simple_create(struct ttm_buffer_object *bo,
+					   uint32_t page_flags)
+{
+	struct ttm_tt *tt;
+
+	tt = kzalloc(sizeof(*tt), GFP_KERNEL);
+	ttm_tt_init(tt, bo, page_flags, ttm_cached, 0);
+
+	return tt;
+}
+
+static void ttm_tt_simple_destroy(struct ttm_device *bdev, struct ttm_tt *ttm)
+{
+	kfree(ttm);
+}
+
 struct ttm_device_funcs ttm_dev_funcs = {
+	.ttm_tt_create = ttm_tt_simple_create,
+	.ttm_tt_destroy = ttm_tt_simple_destroy,
 };
 EXPORT_SYMBOL_GPL(ttm_dev_funcs);
 

drivers/gpu/drm/ttm/tests/ttm_tt_test.c

+// SPDX-License-Identifier: GPL-2.0 AND MIT
+/*
+ * Copyright © 2023 Intel Corporation
+ */
+#include <linux/shmem_fs.h>
+#include <drm/ttm/ttm_tt.h>
+
+#include "ttm_kunit_helpers.h"
+
+#define BO_SIZE		SZ_4K
+
+struct ttm_tt_test_case {
+	const char *description;
+	uint32_t size;
+	uint32_t extra_pages_num;
+};
+
+static int ttm_tt_test_init(struct kunit *test)
+{
+	struct ttm_test_devices *priv;
+
+	priv = kunit_kzalloc(test, sizeof(*priv), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_NULL(test, priv);
+
+	priv = ttm_test_devices_all(test);
+	test->priv = priv;
+
+	return 0;
+}
+
+static const struct ttm_tt_test_case ttm_tt_init_basic_cases[] = {
+	{
+		.description = "Page-aligned size",
+		.size = SZ_4K,
+	},
+	{
+		.description = "Extra pages requested",
+		.size = SZ_4K,
+		.extra_pages_num = 1,
+	},
+};
+
+static void ttm_tt_init_case_desc(const struct ttm_tt_test_case *t,
+				  char *desc)
+{
+	strscpy(desc, t->description, KUNIT_PARAM_DESC_SIZE);
+}
+
+KUNIT_ARRAY_PARAM(ttm_tt_init_basic, ttm_tt_init_basic_cases,
+		  ttm_tt_init_case_desc);
+
+static void ttm_tt_init_basic(struct kunit *test)
+{
+	const struct ttm_tt_test_case *params = test->param_value;
+	struct ttm_buffer_object *bo;
+	struct ttm_tt *tt;
+	uint32_t page_flags = TTM_TT_FLAG_ZERO_ALLOC;
+	enum ttm_caching caching = ttm_cached;
+	uint32_t extra_pages = params->extra_pages_num;
+	int num_pages = params->size >> PAGE_SHIFT;
+	int err;
+
+	tt = kunit_kzalloc(test, sizeof(*tt), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_NULL(test, tt);
+
+	bo = ttm_bo_kunit_init(test, test->priv, params->size);
+
+	err = ttm_tt_init(tt, bo, page_flags, caching, extra_pages);
+	KUNIT_ASSERT_EQ(test, err, 0);
+
+	KUNIT_ASSERT_EQ(test, tt->num_pages, num_pages + extra_pages);
+
+	KUNIT_ASSERT_EQ(test, tt->page_flags, page_flags);
+	KUNIT_ASSERT_EQ(test, tt->caching, caching);
+
+	KUNIT_ASSERT_NULL(test, tt->dma_address);
+	KUNIT_ASSERT_NULL(test, tt->swap_storage);
+}
+
+static void ttm_tt_init_misaligned(struct kunit *test)
+{
+	struct ttm_buffer_object *bo;
+	struct ttm_tt *tt;
+	enum ttm_caching caching = ttm_cached;
+	uint32_t size = SZ_8K;
+	int num_pages = (size + SZ_4K) >> PAGE_SHIFT;
+	int err;
+
+	tt = kunit_kzalloc(test, sizeof(*tt), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_NULL(test, tt);
+
+	bo = ttm_bo_kunit_init(test, test->priv, size);
+
+	/* Make the object size misaligned */
+	bo->base.size += 1;
+
+	err = ttm_tt_init(tt, bo, 0, caching, 0);
+	KUNIT_ASSERT_EQ(test, err, 0);
+
+	KUNIT_ASSERT_EQ(test, tt->num_pages, num_pages);
+}
+
+static void ttm_tt_fini_basic(struct kunit *test)
+{
+	struct ttm_buffer_object *bo;
+	struct ttm_tt *tt;
+	enum ttm_caching caching = ttm_cached;
+	int err;
+
+	tt = kunit_kzalloc(test, sizeof(*tt), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_NULL(test, tt);
+
+	bo = ttm_bo_kunit_init(test, test->priv, BO_SIZE);
+
+	err = ttm_tt_init(tt, bo, 0, caching, 0);
+	KUNIT_ASSERT_EQ(test, err, 0);
+	KUNIT_ASSERT_NOT_NULL(test, tt->pages);
+
+	ttm_tt_fini(tt);
+	KUNIT_ASSERT_NULL(test, tt->pages);
+}
+
+static void ttm_tt_fini_sg(struct kunit *test)
+{
+	struct ttm_buffer_object *bo;
+	struct ttm_tt *tt;
+	enum ttm_caching caching = ttm_cached;
+	int err;
+
+	tt = kunit_kzalloc(test, sizeof(*tt), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_NULL(test, tt);
+
+	bo = ttm_bo_kunit_init(test, test->priv, BO_SIZE);
+
+	err = ttm_sg_tt_init(tt, bo, 0, caching);
+	KUNIT_ASSERT_EQ(test, err, 0);
+	KUNIT_ASSERT_NOT_NULL(test, tt->dma_address);
+
+	ttm_tt_fini(tt);
+	KUNIT_ASSERT_NULL(test, tt->dma_address);
+}
+
+static void ttm_tt_fini_shmem(struct kunit *test)
+{
+	struct ttm_buffer_object *bo;
+	struct ttm_tt *tt;
+	struct file *shmem;
+	enum ttm_caching caching = ttm_cached;
+	int err;
+
+	tt = kunit_kzalloc(test, sizeof(*tt), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_NULL(test, tt);
+
+	bo = ttm_bo_kunit_init(test, test->priv, BO_SIZE);
+
+	err = ttm_tt_init(tt, bo, 0, caching, 0);
+	KUNIT_ASSERT_EQ(test, err, 0);
+
+	shmem = shmem_file_setup("ttm swap", BO_SIZE, 0);
+	tt->swap_storage = shmem;
+
+	ttm_tt_fini(tt);
+	KUNIT_ASSERT_NULL(test, tt->swap_storage);
+}
+
+static void ttm_tt_create_basic(struct kunit *test)
+{
+	struct ttm_buffer_object *bo;
+	int err;
+
+	bo = ttm_bo_kunit_init(test, test->priv, BO_SIZE);
+	bo->type = ttm_bo_type_device;
+
+	dma_resv_lock(bo->base.resv, NULL);
+	err = ttm_tt_create(bo, false);
+	dma_resv_unlock(bo->base.resv);
+
+	KUNIT_EXPECT_EQ(test, err, 0);
+	KUNIT_EXPECT_NOT_NULL(test, bo->ttm);
+
+	/* Free manually, as it was allocated outside of KUnit */
+	kfree(bo->ttm);
+}
+
+static void ttm_tt_create_invalid_bo_type(struct kunit *test)
+{
+	struct ttm_buffer_object *bo;
+	int err;
+
+	bo = ttm_bo_kunit_init(test, test->priv, BO_SIZE);
+	bo->type = ttm_bo_type_sg + 1;
+
+	dma_resv_lock(bo->base.resv, NULL);
+	err = ttm_tt_create(bo, false);
+	dma_resv_unlock(bo->base.resv);
+
+	KUNIT_EXPECT_EQ(test, err, -EINVAL);
+	KUNIT_EXPECT_NULL(test, bo->ttm);
+}
+
+static void ttm_tt_create_ttm_exists(struct kunit *test)
+{
+	struct ttm_buffer_object *bo;
+	struct ttm_tt *tt;
+	enum ttm_caching caching = ttm_cached;
+	int err;
+
+	tt = kunit_kzalloc(test, sizeof(*tt), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_NULL(test, tt);
+
+	bo = ttm_bo_kunit_init(test, test->priv, BO_SIZE);
+
+	err = ttm_tt_init(tt, bo, 0, caching, 0);
+	KUNIT_ASSERT_EQ(test, err, 0);
+	bo->ttm = tt;
+
+	dma_resv_lock(bo->base.resv, NULL);
+	err = ttm_tt_create(bo, false);
+	dma_resv_unlock(bo->base.resv);
+
+	/* Expect to keep the previous TTM */
+	KUNIT_ASSERT_EQ(test, err, 0);
+	KUNIT_ASSERT_PTR_EQ(test, tt, bo->ttm);
+}
+
+static struct ttm_tt *ttm_tt_null_create(struct ttm_buffer_object *bo,
+					 uint32_t page_flags)
+{
+	return NULL;
+}
+
+static struct ttm_device_funcs ttm_dev_empty_funcs = {
+	.ttm_tt_create = ttm_tt_null_create,
+};
+
+static void ttm_tt_create_failed(struct kunit *test)
+{
+	const struct ttm_test_devices *devs = test->priv;
+	struct ttm_buffer_object *bo;
+	int err;
+
+	bo = ttm_bo_kunit_init(test, test->priv, BO_SIZE);
+
+	/* Update ttm_device_funcs so we don't alloc ttm_tt */
+	devs->ttm_dev->funcs = &ttm_dev_empty_funcs;
+
+	dma_resv_lock(bo->base.resv, NULL);
+	err = ttm_tt_create(bo, false);
+	dma_resv_unlock(bo->base.resv);
+
+	KUNIT_ASSERT_EQ(test, err, -ENOMEM);
+}
+
+static void ttm_tt_destroy_basic(struct kunit *test)
+{
+	const struct ttm_test_devices *devs = test->priv;
+	struct ttm_buffer_object *bo;
+	int err;
+
+	bo = ttm_bo_kunit_init(test, test->priv, BO_SIZE);
+
+	dma_resv_lock(bo->base.resv, NULL);
+	err = ttm_tt_create(bo, false);
+	dma_resv_unlock(bo->base.resv);
+
+	KUNIT_ASSERT_EQ(test, err, 0);
+	KUNIT_ASSERT_NOT_NULL(test, bo->ttm);
+
+	ttm_tt_destroy(devs->ttm_dev, bo->ttm);
+}
+
+static struct kunit_case ttm_tt_test_cases[] = {
+	KUNIT_CASE_PARAM(ttm_tt_init_basic, ttm_tt_init_basic_gen_params),
+	KUNIT_CASE(ttm_tt_init_misaligned),
+	KUNIT_CASE(ttm_tt_fini_basic),
+	KUNIT_CASE(ttm_tt_fini_sg),
+	KUNIT_CASE(ttm_tt_fini_shmem),
+	KUNIT_CASE(ttm_tt_create_basic),
+	KUNIT_CASE(ttm_tt_create_invalid_bo_type),
+	KUNIT_CASE(ttm_tt_create_ttm_exists),
+	KUNIT_CASE(ttm_tt_create_failed),
+	KUNIT_CASE(ttm_tt_destroy_basic),
+	{}
+};
+
+static struct kunit_suite ttm_tt_test_suite = {
+	.name = "ttm_tt",
+	.init = ttm_tt_test_init,
+	.exit = ttm_test_devices_fini,
+	.test_cases = ttm_tt_test_cases,
+};
+
+kunit_test_suites(&ttm_tt_test_suite);
+
+MODULE_LICENSE("GPL");

drivers/gpu/drm/ttm/ttm_tt.c

@@ -36,6 +36,7 @@
 #include <linux/file.h>
 #include <linux/module.h>
 #include <drm/drm_cache.h>
+#include <drm/drm_util.h>
 #include <drm/ttm/ttm_bo.h>
 #include <drm/ttm/ttm_tt.h>
 
@@ -91,6 +92,7 @@ int ttm_tt_create(struct ttm_buffer_object *bo, bool zero_alloc)
 
 	return 0;
 }
+EXPORT_SYMBOL_FOR_TESTS_ONLY(ttm_tt_create);
 
 /*
  * Allocates storage for pointers to the pages that back the ttm.
@@ -129,6 +131,7 @@ void ttm_tt_destroy(struct ttm_device *bdev, struct ttm_tt *ttm)
 {
 	bdev->funcs->ttm_tt_destroy(bdev, ttm);
 }
+EXPORT_SYMBOL_FOR_TESTS_ONLY(ttm_tt_destroy);
 
 static void ttm_tt_init_fields(struct ttm_tt *ttm,
 			       struct ttm_buffer_object *bo,