dma-buf: Change st-dma-resv.c to use kunit

Modernize the open coded test framework by using kunit.

The kunit tool can be used to build a kernel and run it in a VM with:

$ tools/testing/kunit/kunit.py run --build_dir build_kunit_x86_64 --arch x86_64 --kunitconfig ./drivers/dma-buf/.kunitconfig

Along with the other ways to run kunits.

To make the kunit tool work like this the DMABUF_KUNIT_TEST kconfig must
select DMA_SHARED_BUFFER to get it turned on without building a driver
using it.

Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Christian König <christian.koenig@amd.com>
Link: https://lore.kernel.org/r/1-v1-0a349a394eff+14110-dmabuf_kunit_jgg@nvidia.com

drivers/dma-buf/.kunitconfig

@@ -0,0 +1,2 @@
+CONFIG_KUNIT=y
+CONFIG_DMABUF_KUNIT_TEST=y

drivers/dma-buf/Kconfig

@@ -54,6 +54,14 @@ config DMABUF_SELFTESTS
 	default n
 	depends on DMA_SHARED_BUFFER
 
+config DMABUF_KUNIT_TEST
+	tristate "KUnit tests for DMA-BUF" if !KUNIT_ALL_TESTS
+	depends on KUNIT
+	select DMA_SHARED_BUFFER
+	default KUNIT_ALL_TESTS
+	help
+	   Enable kunit tests for DMA-BUF
+
 menuconfig DMABUF_HEAPS
 	bool "DMA-BUF Userland Memory Heaps"
 	select DMA_SHARED_BUFFER

drivers/dma-buf/Makefile

@@ -11,7 +11,11 @@ dmabuf_selftests-y := \
 	selftest.o \
 	st-dma-fence.o \
 	st-dma-fence-chain.o \
-	st-dma-fence-unwrap.o \
-	st-dma-resv.o
+	st-dma-fence-unwrap.o
 
 obj-$(CONFIG_DMABUF_SELFTESTS)	+= dmabuf_selftests.o
+
+dmabuf_kunit-y := \
+	st-dma-resv.o
+
+obj-$(CONFIG_DMABUF_KUNIT_TEST) += dmabuf_kunit.o

drivers/dma-buf/selftests.h

@@ -13,4 +13,3 @@ selftest(sanitycheck, __sanitycheck__) /* keep first (igt selfcheck) */
 selftest(dma_fence, dma_fence)
 selftest(dma_fence_chain, dma_fence_chain)
 selftest(dma_fence_unwrap, dma_fence_unwrap)
-selftest(dma_resv, dma_resv)

drivers/dma-buf/st-dma-resv.c

@@ -5,13 +5,17 @@
 * Copyright © 2021 Advanced Micro Devices, Inc.
 */
 
+#include <kunit/test.h>
 #include <linux/slab.h>
 #include <linux/spinlock.h>
 #include <linux/dma-resv.h>
 
-#include "selftest.h"
+static DEFINE_SPINLOCK(fence_lock);
 
-static struct spinlock fence_lock;
+struct dma_resv_usage_param {
+	enum dma_resv_usage usage;
+	const char *desc;
+};
 
 static const char *fence_name(struct dma_fence *f)
 {
@@ -35,15 +39,14 @@ static struct dma_fence *alloc_fence(void)
 	return f;
 }
 
-static int sanitycheck(void *arg)
+static void test_sanitycheck(struct kunit *test)
 {
 	struct dma_resv resv;
 	struct dma_fence *f;
 	int r;
 
 	f = alloc_fence();
-	if (!f)
-		return -ENOMEM;
+	KUNIT_ASSERT_NOT_NULL(test, f);
 
 	dma_fence_enable_sw_signaling(f);
 
@@ -53,49 +56,46 @@ static int sanitycheck(void *arg)
 	dma_resv_init(&resv);
 	r = dma_resv_lock(&resv, NULL);
 	if (r)
-		pr_err("Resv locking failed\n");
+		KUNIT_FAIL(test, "Resv locking failed\n");
 	else
 		dma_resv_unlock(&resv);
 	dma_resv_fini(&resv);
-	return r;
 }
 
-static int test_signaling(void *arg)
+static void test_signaling(struct kunit *test)
 {
-	enum dma_resv_usage usage = (unsigned long)arg;
+	const struct dma_resv_usage_param *param = test->param_value;
+	enum dma_resv_usage usage = param->usage;
 	struct dma_resv resv;
 	struct dma_fence *f;
 	int r;
 
 	f = alloc_fence();
-	if (!f)
-		return -ENOMEM;
+	KUNIT_ASSERT_NOT_NULL(test, f);
 
 	dma_fence_enable_sw_signaling(f);
 
 	dma_resv_init(&resv);
 	r = dma_resv_lock(&resv, NULL);
 	if (r) {
-		pr_err("Resv locking failed\n");
+		KUNIT_FAIL(test, "Resv locking failed");
 		goto err_free;
 	}
 
 	r = dma_resv_reserve_fences(&resv, 1);
 	if (r) {
-		pr_err("Resv shared slot allocation failed\n");
+		KUNIT_FAIL(test, "Resv shared slot allocation failed");
 		goto err_unlock;
 	}
 
 	dma_resv_add_fence(&resv, f, usage);
 	if (dma_resv_test_signaled(&resv, usage)) {
-		pr_err("Resv unexpectedly signaled\n");
-		r = -EINVAL;
+		KUNIT_FAIL(test, "Resv unexpectedly signaled");
 		goto err_unlock;
 	}
 	dma_fence_signal(f);
 	if (!dma_resv_test_signaled(&resv, usage)) {
-		pr_err("Resv not reporting signaled\n");
-		r = -EINVAL;
+		KUNIT_FAIL(test, "Resv not reporting signaled");
 		goto err_unlock;
 	}
 err_unlock:
@@ -103,33 +103,32 @@ static int test_signaling(void *arg)
 err_free:
 	dma_resv_fini(&resv);
 	dma_fence_put(f);
-	return r;
 }
 
-static int test_for_each(void *arg)
+static void test_for_each(struct kunit *test)
 {
-	enum dma_resv_usage usage = (unsigned long)arg;
+	const struct dma_resv_usage_param *param = test->param_value;
+	enum dma_resv_usage usage = param->usage;
 	struct dma_resv_iter cursor;
 	struct dma_fence *f, *fence;
 	struct dma_resv resv;
 	int r;
 
 	f = alloc_fence();
-	if (!f)
-		return -ENOMEM;
+	KUNIT_ASSERT_NOT_NULL(test, f);
 
 	dma_fence_enable_sw_signaling(f);
 
 	dma_resv_init(&resv);
 	r = dma_resv_lock(&resv, NULL);
 	if (r) {
-		pr_err("Resv locking failed\n");
+		KUNIT_FAIL(test, "Resv locking failed");
 		goto err_free;
 	}
 
 	r = dma_resv_reserve_fences(&resv, 1);
 	if (r) {
-		pr_err("Resv shared slot allocation failed\n");
+		KUNIT_FAIL(test, "Resv shared slot allocation failed");
 		goto err_unlock;
 	}
 
@@ -138,24 +137,23 @@ static int test_for_each(void *arg)
 	r = -ENOENT;
 	dma_resv_for_each_fence(&cursor, &resv, usage, fence) {
 		if (!r) {
-			pr_err("More than one fence found\n");
-			r = -EINVAL;
+			KUNIT_FAIL(test, "More than one fence found");
 			goto err_unlock;
 		}
 		if (f != fence) {
-			pr_err("Unexpected fence\n");
+			KUNIT_FAIL(test, "Unexpected fence");
 			r = -EINVAL;
 			goto err_unlock;
 		}
 		if (dma_resv_iter_usage(&cursor) != usage) {
-			pr_err("Unexpected fence usage\n");
+			KUNIT_FAIL(test, "Unexpected fence usage");
 			r = -EINVAL;
 			goto err_unlock;
 		}
 		r = 0;
 	}
 	if (r) {
-		pr_err("No fence found\n");
+		KUNIT_FAIL(test, "No fence found");
 		goto err_unlock;
 	}
 	dma_fence_signal(f);
@@ -164,33 +162,32 @@ static int test_for_each(void *arg)
 err_free:
 	dma_resv_fini(&resv);
 	dma_fence_put(f);
-	return r;
 }
 
-static int test_for_each_unlocked(void *arg)
+static void test_for_each_unlocked(struct kunit *test)
 {
-	enum dma_resv_usage usage = (unsigned long)arg;
+	const struct dma_resv_usage_param *param = test->param_value;
+	enum dma_resv_usage usage = param->usage;
 	struct dma_resv_iter cursor;
 	struct dma_fence *f, *fence;
 	struct dma_resv resv;
 	int r;
 
 	f = alloc_fence();
-	if (!f)
-		return -ENOMEM;
+	KUNIT_ASSERT_NOT_NULL(test, f);
 
 	dma_fence_enable_sw_signaling(f);
 
 	dma_resv_init(&resv);
 	r = dma_resv_lock(&resv, NULL);
 	if (r) {
-		pr_err("Resv locking failed\n");
+		KUNIT_FAIL(test, "Resv locking failed");
 		goto err_free;
 	}
 
 	r = dma_resv_reserve_fences(&resv, 1);
 	if (r) {
-		pr_err("Resv shared slot allocation failed\n");
+		KUNIT_FAIL(test, "Resv shared slot allocation failed");
 		dma_resv_unlock(&resv);
 		goto err_free;
 	}
@@ -202,21 +199,20 @@ static int test_for_each_unlocked(void *arg)
 	dma_resv_iter_begin(&cursor, &resv, usage);
 	dma_resv_for_each_fence_unlocked(&cursor, fence) {
 		if (!r) {
-			pr_err("More than one fence found\n");
-			r = -EINVAL;
+			KUNIT_FAIL(test, "More than one fence found");
 			goto err_iter_end;
 		}
 		if (!dma_resv_iter_is_restarted(&cursor)) {
-			pr_err("No restart flag\n");
+			KUNIT_FAIL(test, "No restart flag");
 			goto err_iter_end;
 		}
 		if (f != fence) {
-			pr_err("Unexpected fence\n");
+			KUNIT_FAIL(test, "Unexpected fence");
 			r = -EINVAL;
 			goto err_iter_end;
 		}
 		if (dma_resv_iter_usage(&cursor) != usage) {
-			pr_err("Unexpected fence usage\n");
+			KUNIT_FAIL(test, "Unexpected fence usage");
 			r = -EINVAL;
 			goto err_iter_end;
 		}
@@ -230,40 +226,38 @@ static int test_for_each_unlocked(void *arg)
 			r = 0;
 		}
 	}
-	if (r)
-		pr_err("No fence found\n");
+	KUNIT_EXPECT_EQ(test, r, 0);
 err_iter_end:
 	dma_resv_iter_end(&cursor);
 	dma_fence_signal(f);
 err_free:
 	dma_resv_fini(&resv);
 	dma_fence_put(f);
-	return r;
 }
 
-static int test_get_fences(void *arg)
+static void test_get_fences(struct kunit *test)
 {
-	enum dma_resv_usage usage = (unsigned long)arg;
+	const struct dma_resv_usage_param *param = test->param_value;
+	enum dma_resv_usage usage = param->usage;
 	struct dma_fence *f, **fences = NULL;
 	struct dma_resv resv;
 	int r, i;
 
 	f = alloc_fence();
-	if (!f)
-		return -ENOMEM;
+	KUNIT_ASSERT_NOT_NULL(test, f);
 
 	dma_fence_enable_sw_signaling(f);
 
 	dma_resv_init(&resv);
 	r = dma_resv_lock(&resv, NULL);
 	if (r) {
-		pr_err("Resv locking failed\n");
+		KUNIT_FAIL(test, "Resv locking failed");
 		goto err_resv;
 	}
 
 	r = dma_resv_reserve_fences(&resv, 1);
 	if (r) {
-		pr_err("Resv shared slot allocation failed\n");
+		KUNIT_FAIL(test, "Resv shared slot allocation failed");
 		dma_resv_unlock(&resv);
 		goto err_resv;
 	}
@@ -273,12 +267,12 @@ static int test_get_fences(void *arg)
 
 	r = dma_resv_get_fences(&resv, usage, &i, &fences);
 	if (r) {
-		pr_err("get_fences failed\n");
+		KUNIT_FAIL(test, "get_fences failed");
 		goto err_free;
 	}
 
 	if (i != 1 || fences[0] != f) {
-		pr_err("get_fences returned unexpected fence\n");
+		KUNIT_FAIL(test, "get_fences returned unexpected fence");
 		goto err_free;
 	}
 
@@ -290,27 +284,32 @@ static int test_get_fences(void *arg)
 err_resv:
 	dma_resv_fini(&resv);
 	dma_fence_put(f);
-	return r;
 }
 
-int dma_resv(void)
-{
-	static const struct subtest tests[] = {
-		SUBTEST(sanitycheck),
-		SUBTEST(test_signaling),
-		SUBTEST(test_for_each),
-		SUBTEST(test_for_each_unlocked),
-		SUBTEST(test_get_fences),
-	};
-	enum dma_resv_usage usage;
-	int r;
+static const struct dma_resv_usage_param dma_resv_usage_params[] = {
+	{ DMA_RESV_USAGE_KERNEL, "kernel" },
+	{ DMA_RESV_USAGE_WRITE, "write" },
+	{ DMA_RESV_USAGE_READ, "read" },
+	{ DMA_RESV_USAGE_BOOKKEEP, "bookkeep" },
+};
 
-	spin_lock_init(&fence_lock);
-	for (usage = DMA_RESV_USAGE_KERNEL; usage <= DMA_RESV_USAGE_BOOKKEEP;
-	     ++usage) {
-		r = subtests(tests, (void *)(unsigned long)usage);
-		if (r)
-			return r;
-	}
-	return 0;
-}
+KUNIT_ARRAY_PARAM_DESC(dma_resv_usage, dma_resv_usage_params, desc);
+
+static struct kunit_case dma_resv_cases[] = {
+	KUNIT_CASE(test_sanitycheck),
+	KUNIT_CASE_PARAM(test_signaling, dma_resv_usage_gen_params),
+	KUNIT_CASE_PARAM(test_for_each, dma_resv_usage_gen_params),
+	KUNIT_CASE_PARAM(test_for_each_unlocked, dma_resv_usage_gen_params),
+	KUNIT_CASE_PARAM(test_get_fences, dma_resv_usage_gen_params),
+	{}
+};
+
+static struct kunit_suite dma_resv_test_suite = {
+	.name = "dma-buf-resv",
+	.test_cases = dma_resv_cases,
+};
+
+kunit_test_suite(dma_resv_test_suite);
+
+MODULE_DESCRIPTION("KUnit tests for DMA-BUF");
+MODULE_LICENSE("GPL");