Adding upstream version 5.10.209.upstream/5.10.209upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

14 files changed, 2013 insertions, 0 deletions

diff --git a/lib/kunit/Kconfig b/lib/kunit/Kconfig
new file mode 100644
index 000000000..00909e6a2
--- /dev/null
+++ b/lib/kunit/Kconfig
@@ -0,0 +1,61 @@
+#
+# KUnit base configuration
+#
+
+menuconfig KUNIT
+	tristate "KUnit - Enable support for unit tests"
+	help
+	  Enables support for kernel unit tests (KUnit), a lightweight unit
+	  testing and mocking framework for the Linux kernel. These tests are
+	  able to be run locally on a developer's workstation without a VM or
+	  special hardware when using UML. Can also be used on most other
+	  architectures. For more information, please see
+	  Documentation/dev-tools/kunit/.
+
+if KUNIT
+
+config KUNIT_DEBUGFS
+	bool "KUnit - Enable /sys/kernel/debug/kunit debugfs representation" if !KUNIT_ALL_TESTS
+	default KUNIT_ALL_TESTS
+	help
+	  Enable debugfs representation for kunit.  Currently this consists
+	  of /sys/kernel/debug/kunit/<test_suite>/results files for each
+	  test suite, which allow users to see results of the last test suite
+	  run that occurred.
+
+config KUNIT_TEST
+	tristate "KUnit test for KUnit" if !KUNIT_ALL_TESTS
+	default KUNIT_ALL_TESTS
+	help
+	  Enables the unit tests for the KUnit test framework. These tests test
+	  the KUnit test framework itself; the tests are both written using
+	  KUnit and test KUnit. This option should only be enabled for testing
+	  purposes by developers interested in testing that KUnit works as
+	  expected.
+
+config KUNIT_EXAMPLE_TEST
+	tristate "Example test for KUnit" if !KUNIT_ALL_TESTS
+	default KUNIT_ALL_TESTS
+	help
+	  Enables an example unit test that illustrates some of the basic
+	  features of KUnit. This test only exists to help new users understand
+	  what KUnit is and how it is used. Please refer to the example test
+	  itself, lib/kunit/example-test.c, for more information. This option
+	  is intended for curious hackers who would like to understand how to
+	  use KUnit for kernel development.
+
+config KUNIT_ALL_TESTS
+	tristate "All KUnit tests with satisfied dependencies"
+	help
+	  Enables all KUnit tests, if they can be enabled.
+	  KUnit tests run during boot and output the results to the debug log
+	  in TAP format (http://testanything.org/). Only useful for kernel devs
+	  running the KUnit test harness, and not intended for inclusion into a
+	  production build.
+
+	  For more information on KUnit and unit tests in general please refer
+	  to the KUnit documentation in Documentation/dev-tools/kunit/.
+
+	  If unsure, say N.
+
+endif # KUNIT
diff --git a/lib/kunit/Makefile b/lib/kunit/Makefile
new file mode 100644
index 000000000..c49f4ffb6
--- /dev/null
+++ b/lib/kunit/Makefile
@@ -0,0 +1,20 @@
+obj-$(CONFIG_KUNIT) +=			kunit.o
+
+kunit-objs +=				test.o \
+					string-stream.o \
+					assert.o \
+					try-catch.o \
+					executor.o
+
+ifeq ($(CONFIG_KUNIT_DEBUGFS),y)
+kunit-objs +=				debugfs.o
+endif
+
+obj-$(CONFIG_KUNIT_TEST) +=		kunit-test.o
+
+# string-stream-test compiles built-in only.
+ifeq ($(CONFIG_KUNIT_TEST),y)
+obj-$(CONFIG_KUNIT_TEST) +=		string-stream-test.o
+endif
+
+obj-$(CONFIG_KUNIT_EXAMPLE_TEST) +=	kunit-example-test.o
diff --git a/lib/kunit/assert.c b/lib/kunit/assert.c
new file mode 100644
index 000000000..33acdaa28
--- /dev/null
+++ b/lib/kunit/assert.c
@@ -0,0 +1,152 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Assertion and expectation serialization API.
+ *
+ * Copyright (C) 2019, Google LLC.
+ * Author: Brendan Higgins <brendanhiggins@google.com>
+ */
+#include <kunit/assert.h>
+#include <kunit/test.h>
+
+#include "string-stream.h"
+
+void kunit_base_assert_format(const struct kunit_assert *assert,
+			      struct string_stream *stream)
+{
+	const char *expect_or_assert = NULL;
+
+	switch (assert->type) {
+	case KUNIT_EXPECTATION:
+		expect_or_assert = "EXPECTATION";
+		break;
+	case KUNIT_ASSERTION:
+		expect_or_assert = "ASSERTION";
+		break;
+	}
+
+	string_stream_add(stream, "%s FAILED at %s:%d\n",
+			 expect_or_assert, assert->file, assert->line);
+}
+EXPORT_SYMBOL_GPL(kunit_base_assert_format);
+
+void kunit_assert_print_msg(const struct kunit_assert *assert,
+			    struct string_stream *stream)
+{
+	if (assert->message.fmt)
+		string_stream_add(stream, "\n%pV", &assert->message);
+}
+EXPORT_SYMBOL_GPL(kunit_assert_print_msg);
+
+void kunit_fail_assert_format(const struct kunit_assert *assert,
+			      struct string_stream *stream)
+{
+	kunit_base_assert_format(assert, stream);
+	string_stream_add(stream, "%pV", &assert->message);
+}
+EXPORT_SYMBOL_GPL(kunit_fail_assert_format);
+
+void kunit_unary_assert_format(const struct kunit_assert *assert,
+			       struct string_stream *stream)
+{
+	struct kunit_unary_assert *unary_assert = container_of(
+			assert, struct kunit_unary_assert, assert);
+
+	kunit_base_assert_format(assert, stream);
+	if (unary_assert->expected_true)
+		string_stream_add(stream,
+				  KUNIT_SUBTEST_INDENT "Expected %s to be true, but is false\n",
+				  unary_assert->condition);
+	else
+		string_stream_add(stream,
+				  KUNIT_SUBTEST_INDENT "Expected %s to be false, but is true\n",
+				  unary_assert->condition);
+	kunit_assert_print_msg(assert, stream);
+}
+EXPORT_SYMBOL_GPL(kunit_unary_assert_format);
+
+void kunit_ptr_not_err_assert_format(const struct kunit_assert *assert,
+				     struct string_stream *stream)
+{
+	struct kunit_ptr_not_err_assert *ptr_assert = container_of(
+			assert, struct kunit_ptr_not_err_assert, assert);
+
+	kunit_base_assert_format(assert, stream);
+	if (!ptr_assert->value) {
+		string_stream_add(stream,
+				  KUNIT_SUBTEST_INDENT "Expected %s is not null, but is\n",
+				  ptr_assert->text);
+	} else if (IS_ERR(ptr_assert->value)) {
+		string_stream_add(stream,
+				  KUNIT_SUBTEST_INDENT "Expected %s is not error, but is: %ld\n",
+				  ptr_assert->text,
+				  PTR_ERR(ptr_assert->value));
+	}
+	kunit_assert_print_msg(assert, stream);
+}
+EXPORT_SYMBOL_GPL(kunit_ptr_not_err_assert_format);
+
+void kunit_binary_assert_format(const struct kunit_assert *assert,
+				struct string_stream *stream)
+{
+	struct kunit_binary_assert *binary_assert = container_of(
+			assert, struct kunit_binary_assert, assert);
+
+	kunit_base_assert_format(assert, stream);
+	string_stream_add(stream,
+			  KUNIT_SUBTEST_INDENT "Expected %s %s %s, but\n",
+			  binary_assert->left_text,
+			  binary_assert->operation,
+			  binary_assert->right_text);
+	string_stream_add(stream, KUNIT_SUBSUBTEST_INDENT "%s == %lld\n",
+			  binary_assert->left_text,
+			  binary_assert->left_value);
+	string_stream_add(stream, KUNIT_SUBSUBTEST_INDENT "%s == %lld",
+			  binary_assert->right_text,
+			  binary_assert->right_value);
+	kunit_assert_print_msg(assert, stream);
+}
+EXPORT_SYMBOL_GPL(kunit_binary_assert_format);
+
+void kunit_binary_ptr_assert_format(const struct kunit_assert *assert,
+				    struct string_stream *stream)
+{
+	struct kunit_binary_ptr_assert *binary_assert = container_of(
+			assert, struct kunit_binary_ptr_assert, assert);
+
+	kunit_base_assert_format(assert, stream);
+	string_stream_add(stream,
+			  KUNIT_SUBTEST_INDENT "Expected %s %s %s, but\n",
+			  binary_assert->left_text,
+			  binary_assert->operation,
+			  binary_assert->right_text);
+	string_stream_add(stream, KUNIT_SUBSUBTEST_INDENT "%s == %px\n",
+			  binary_assert->left_text,
+			  binary_assert->left_value);
+	string_stream_add(stream, KUNIT_SUBSUBTEST_INDENT "%s == %px",
+			  binary_assert->right_text,
+			  binary_assert->right_value);
+	kunit_assert_print_msg(assert, stream);
+}
+EXPORT_SYMBOL_GPL(kunit_binary_ptr_assert_format);
+
+void kunit_binary_str_assert_format(const struct kunit_assert *assert,
+				    struct string_stream *stream)
+{
+	struct kunit_binary_str_assert *binary_assert = container_of(
+			assert, struct kunit_binary_str_assert, assert);
+
+	kunit_base_assert_format(assert, stream);
+	string_stream_add(stream,
+			  KUNIT_SUBTEST_INDENT "Expected %s %s %s, but\n",
+			  binary_assert->left_text,
+			  binary_assert->operation,
+			  binary_assert->right_text);
+	string_stream_add(stream, KUNIT_SUBSUBTEST_INDENT "%s == %s\n",
+			  binary_assert->left_text,
+			  binary_assert->left_value);
+	string_stream_add(stream, KUNIT_SUBSUBTEST_INDENT "%s == %s",
+			  binary_assert->right_text,
+			  binary_assert->right_value);
+	kunit_assert_print_msg(assert, stream);
+}
+EXPORT_SYMBOL_GPL(kunit_binary_str_assert_format);
diff --git a/lib/kunit/debugfs.c b/lib/kunit/debugfs.c
new file mode 100644
index 000000000..9214c493d
--- /dev/null
+++ b/lib/kunit/debugfs.c
@@ -0,0 +1,116 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2020, Oracle and/or its affiliates.
+ *    Author: Alan Maguire <alan.maguire@oracle.com>
+ */
+
+#include <linux/debugfs.h>
+#include <linux/module.h>
+
+#include <kunit/test.h>
+
+#include "string-stream.h"
+
+#define KUNIT_DEBUGFS_ROOT             "kunit"
+#define KUNIT_DEBUGFS_RESULTS          "results"
+
+/*
+ * Create a debugfs representation of test suites:
+ *
+ * Path						Semantics
+ * /sys/kernel/debug/kunit/<testsuite>/results	Show results of last run for
+ *						testsuite
+ *
+ */
+
+static struct dentry *debugfs_rootdir;
+
+void kunit_debugfs_cleanup(void)
+{
+	debugfs_remove_recursive(debugfs_rootdir);
+}
+
+void kunit_debugfs_init(void)
+{
+	if (!debugfs_rootdir)
+		debugfs_rootdir = debugfs_create_dir(KUNIT_DEBUGFS_ROOT, NULL);
+}
+
+static void debugfs_print_result(struct seq_file *seq,
+				 struct kunit_suite *suite,
+				 struct kunit_case *test_case)
+{
+	if (!test_case || !test_case->log)
+		return;
+
+	seq_printf(seq, "%s", test_case->log);
+}
+
+/*
+ * /sys/kernel/debug/kunit/<testsuite>/results shows all results for testsuite.
+ */
+static int debugfs_print_results(struct seq_file *seq, void *v)
+{
+	struct kunit_suite *suite = (struct kunit_suite *)seq->private;
+	bool success = kunit_suite_has_succeeded(suite);
+	struct kunit_case *test_case;
+
+	if (!suite || !suite->log)
+		return 0;
+
+	seq_printf(seq, "%s", suite->log);
+
+	kunit_suite_for_each_test_case(suite, test_case)
+		debugfs_print_result(seq, suite, test_case);
+
+	seq_printf(seq, "%s %d - %s\n",
+		   kunit_status_to_string(success), 1, suite->name);
+	return 0;
+}
+
+static int debugfs_release(struct inode *inode, struct file *file)
+{
+	return single_release(inode, file);
+}
+
+static int debugfs_results_open(struct inode *inode, struct file *file)
+{
+	struct kunit_suite *suite;
+
+	suite = (struct kunit_suite *)inode->i_private;
+
+	return single_open(file, debugfs_print_results, suite);
+}
+
+static const struct file_operations debugfs_results_fops = {
+	.open = debugfs_results_open,
+	.read = seq_read,
+	.llseek = seq_lseek,
+	.release = debugfs_release,
+};
+
+void kunit_debugfs_create_suite(struct kunit_suite *suite)
+{
+	struct kunit_case *test_case;
+
+	/* Allocate logs before creating debugfs representation. */
+	suite->log = kzalloc(KUNIT_LOG_SIZE, GFP_KERNEL);
+	kunit_suite_for_each_test_case(suite, test_case)
+		test_case->log = kzalloc(KUNIT_LOG_SIZE, GFP_KERNEL);
+
+	suite->debugfs = debugfs_create_dir(suite->name, debugfs_rootdir);
+
+	debugfs_create_file(KUNIT_DEBUGFS_RESULTS, S_IFREG | 0444,
+			    suite->debugfs,
+			    suite, &debugfs_results_fops);
+}
+
+void kunit_debugfs_destroy_suite(struct kunit_suite *suite)
+{
+	struct kunit_case *test_case;
+
+	debugfs_remove_recursive(suite->debugfs);
+	kfree(suite->log);
+	kunit_suite_for_each_test_case(suite, test_case)
+		kfree(test_case->log);
+}
diff --git a/lib/kunit/debugfs.h b/lib/kunit/debugfs.h
new file mode 100644
index 000000000..dcc7d7556
--- /dev/null
+++ b/lib/kunit/debugfs.h
@@ -0,0 +1,30 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2020, Oracle and/or its affiliates.
+ */
+
+#ifndef _KUNIT_DEBUGFS_H
+#define _KUNIT_DEBUGFS_H
+
+#include <kunit/test.h>
+
+#ifdef CONFIG_KUNIT_DEBUGFS
+
+void kunit_debugfs_create_suite(struct kunit_suite *suite);
+void kunit_debugfs_destroy_suite(struct kunit_suite *suite);
+void kunit_debugfs_init(void);
+void kunit_debugfs_cleanup(void);
+
+#else
+
+static inline void kunit_debugfs_create_suite(struct kunit_suite *suite) { }
+
+static inline void kunit_debugfs_destroy_suite(struct kunit_suite *suite) { }
+
+static inline void kunit_debugfs_init(void) { }
+
+static inline void kunit_debugfs_cleanup(void) { }
+
+#endif /* CONFIG_KUNIT_DEBUGFS */
+
+#endif /* _KUNIT_DEBUGFS_H */
diff --git a/lib/kunit/executor.c b/lib/kunit/executor.c
new file mode 100644
index 000000000..a95742a4e
--- /dev/null
+++ b/lib/kunit/executor.c
@@ -0,0 +1,43 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <kunit/test.h>
+
+/*
+ * These symbols point to the .kunit_test_suites section and are defined in
+ * include/asm-generic/vmlinux.lds.h, and consequently must be extern.
+ */
+extern struct kunit_suite * const * const __kunit_suites_start[];
+extern struct kunit_suite * const * const __kunit_suites_end[];
+
+#if IS_BUILTIN(CONFIG_KUNIT)
+
+static void kunit_print_tap_header(void)
+{
+	struct kunit_suite * const * const *suites, * const *subsuite;
+	int num_of_suites = 0;
+
+	for (suites = __kunit_suites_start;
+	     suites < __kunit_suites_end;
+	     suites++)
+		for (subsuite = *suites; *subsuite != NULL; subsuite++)
+			num_of_suites++;
+
+	pr_info("TAP version 14\n");
+	pr_info("1..%d\n", num_of_suites);
+}
+
+int kunit_run_all_tests(void)
+{
+	struct kunit_suite * const * const *suites;
+
+	kunit_print_tap_header();
+
+	for (suites = __kunit_suites_start;
+	     suites < __kunit_suites_end;
+	     suites++)
+			__kunit_test_suites_init(*suites);
+
+	return 0;
+}
+
+#endif /* IS_BUILTIN(CONFIG_KUNIT) */
diff --git a/lib/kunit/kunit-example-test.c b/lib/kunit/kunit-example-test.c
new file mode 100644
index 000000000..be1164ecc
--- /dev/null
+++ b/lib/kunit/kunit-example-test.c
@@ -0,0 +1,90 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Example KUnit test to show how to use KUnit.
+ *
+ * Copyright (C) 2019, Google LLC.
+ * Author: Brendan Higgins <brendanhiggins@google.com>
+ */
+
+#include <kunit/test.h>
+
+/*
+ * This is the most fundamental element of KUnit, the test case. A test case
+ * makes a set EXPECTATIONs and ASSERTIONs about the behavior of some code; if
+ * any expectations or assertions are not met, the test fails; otherwise, the
+ * test passes.
+ *
+ * In KUnit, a test case is just a function with the signature
+ * `void (*)(struct kunit *)`. `struct kunit` is a context object that stores
+ * information about the current test.
+ */
+static void example_simple_test(struct kunit *test)
+{
+	/*
+	 * This is an EXPECTATION; it is how KUnit tests things. When you want
+	 * to test a piece of code, you set some expectations about what the
+	 * code should do. KUnit then runs the test and verifies that the code's
+	 * behavior matched what was expected.
+	 */
+	KUNIT_EXPECT_EQ(test, 1 + 1, 2);
+}
+
+/*
+ * This is run once before each test case, see the comment on
+ * example_test_suite for more information.
+ */
+static int example_test_init(struct kunit *test)
+{
+	kunit_info(test, "initializing\n");
+
+	return 0;
+}
+
+/*
+ * Here we make a list of all the test cases we want to add to the test suite
+ * below.
+ */
+static struct kunit_case example_test_cases[] = {
+	/*
+	 * This is a helper to create a test case object from a test case
+	 * function; its exact function is not important to understand how to
+	 * use KUnit, just know that this is how you associate test cases with a
+	 * test suite.
+	 */
+	KUNIT_CASE(example_simple_test),
+	{}
+};
+
+/*
+ * This defines a suite or grouping of tests.
+ *
+ * Test cases are defined as belonging to the suite by adding them to
+ * `kunit_cases`.
+ *
+ * Often it is desirable to run some function which will set up things which
+ * will be used by every test; this is accomplished with an `init` function
+ * which runs before each test case is invoked. Similarly, an `exit` function
+ * may be specified which runs after every test case and can be used to for
+ * cleanup. For clarity, running tests in a test suite would behave as follows:
+ *
+ * suite.init(test);
+ * suite.test_case[0](test);
+ * suite.exit(test);
+ * suite.init(test);
+ * suite.test_case[1](test);
+ * suite.exit(test);
+ * ...;
+ */
+static struct kunit_suite example_test_suite = {
+	.name = "example",
+	.init = example_test_init,
+	.test_cases = example_test_cases,
+};
+
+/*
+ * This registers the above test suite telling KUnit that this is a suite of
+ * tests that need to be run.
+ */
+kunit_test_suites(&example_test_suite);
+
+MODULE_LICENSE("GPL v2");
diff --git a/lib/kunit/kunit-test.c b/lib/kunit/kunit-test.c
new file mode 100644
index 000000000..69f902440
--- /dev/null
+++ b/lib/kunit/kunit-test.c
@@ -0,0 +1,443 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * KUnit test for core test infrastructure.
+ *
+ * Copyright (C) 2019, Google LLC.
+ * Author: Brendan Higgins <brendanhiggins@google.com>
+ */
+#include <kunit/test.h>
+
+#include "try-catch-impl.h"
+
+struct kunit_try_catch_test_context {
+	struct kunit_try_catch *try_catch;
+	bool function_called;
+};
+
+static void kunit_test_successful_try(void *data)
+{
+	struct kunit *test = data;
+	struct kunit_try_catch_test_context *ctx = test->priv;
+
+	ctx->function_called = true;
+}
+
+static void kunit_test_no_catch(void *data)
+{
+	struct kunit *test = data;
+
+	KUNIT_FAIL(test, "Catch should not be called\n");
+}
+
+static void kunit_test_try_catch_successful_try_no_catch(struct kunit *test)
+{
+	struct kunit_try_catch_test_context *ctx = test->priv;
+	struct kunit_try_catch *try_catch = ctx->try_catch;
+
+	kunit_try_catch_init(try_catch,
+			     test,
+			     kunit_test_successful_try,
+			     kunit_test_no_catch);
+	kunit_try_catch_run(try_catch, test);
+
+	KUNIT_EXPECT_TRUE(test, ctx->function_called);
+}
+
+static void kunit_test_unsuccessful_try(void *data)
+{
+	struct kunit *test = data;
+	struct kunit_try_catch_test_context *ctx = test->priv;
+	struct kunit_try_catch *try_catch = ctx->try_catch;
+
+	kunit_try_catch_throw(try_catch);
+	KUNIT_FAIL(test, "This line should never be reached\n");
+}
+
+static void kunit_test_catch(void *data)
+{
+	struct kunit *test = data;
+	struct kunit_try_catch_test_context *ctx = test->priv;
+
+	ctx->function_called = true;
+}
+
+static void kunit_test_try_catch_unsuccessful_try_does_catch(struct kunit *test)
+{
+	struct kunit_try_catch_test_context *ctx = test->priv;
+	struct kunit_try_catch *try_catch = ctx->try_catch;
+
+	kunit_try_catch_init(try_catch,
+			     test,
+			     kunit_test_unsuccessful_try,
+			     kunit_test_catch);
+	kunit_try_catch_run(try_catch, test);
+
+	KUNIT_EXPECT_TRUE(test, ctx->function_called);
+}
+
+static int kunit_try_catch_test_init(struct kunit *test)
+{
+	struct kunit_try_catch_test_context *ctx;
+
+	ctx = kunit_kzalloc(test, sizeof(*ctx), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+	test->priv = ctx;
+
+	ctx->try_catch = kunit_kmalloc(test,
+				       sizeof(*ctx->try_catch),
+				       GFP_KERNEL);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx->try_catch);
+
+	return 0;
+}
+
+static struct kunit_case kunit_try_catch_test_cases[] = {
+	KUNIT_CASE(kunit_test_try_catch_successful_try_no_catch),
+	KUNIT_CASE(kunit_test_try_catch_unsuccessful_try_does_catch),
+	{}
+};
+
+static struct kunit_suite kunit_try_catch_test_suite = {
+	.name = "kunit-try-catch-test",
+	.init = kunit_try_catch_test_init,
+	.test_cases = kunit_try_catch_test_cases,
+};
+
+/*
+ * Context for testing test managed resources
+ * is_resource_initialized is used to test arbitrary resources
+ */
+struct kunit_test_resource_context {
+	struct kunit test;
+	bool is_resource_initialized;
+	int allocate_order[2];
+	int free_order[2];
+};
+
+static int fake_resource_init(struct kunit_resource *res, void *context)
+{
+	struct kunit_test_resource_context *ctx = context;
+
+	res->data = &ctx->is_resource_initialized;
+	ctx->is_resource_initialized = true;
+	return 0;
+}
+
+static void fake_resource_free(struct kunit_resource *res)
+{
+	bool *is_resource_initialized = res->data;
+
+	*is_resource_initialized = false;
+}
+
+static void kunit_resource_test_init_resources(struct kunit *test)
+{
+	struct kunit_test_resource_context *ctx = test->priv;
+
+	kunit_init_test(&ctx->test, "testing_test_init_test", NULL);
+
+	KUNIT_EXPECT_TRUE(test, list_empty(&ctx->test.resources));
+}
+
+static void kunit_resource_test_alloc_resource(struct kunit *test)
+{
+	struct kunit_test_resource_context *ctx = test->priv;
+	struct kunit_resource *res;
+	kunit_resource_free_t free = fake_resource_free;
+
+	res = kunit_alloc_and_get_resource(&ctx->test,
+					   fake_resource_init,
+					   fake_resource_free,
+					   GFP_KERNEL,
+					   ctx);
+
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, res);
+	KUNIT_EXPECT_PTR_EQ(test,
+			    &ctx->is_resource_initialized,
+			    (bool *)res->data);
+	KUNIT_EXPECT_TRUE(test, list_is_last(&res->node, &ctx->test.resources));
+	KUNIT_EXPECT_PTR_EQ(test, free, res->free);
+
+	kunit_put_resource(res);
+}
+
+/*
+ * Note: tests below use kunit_alloc_and_get_resource(), so as a consequence
+ * they have a reference to the associated resource that they must release
+ * via kunit_put_resource().  In normal operation, users will only
+ * have to do this for cases where they use kunit_find_resource(), and the
+ * kunit_alloc_resource() function will be used (which does not take a
+ * resource reference).
+ */
+static void kunit_resource_test_destroy_resource(struct kunit *test)
+{
+	struct kunit_test_resource_context *ctx = test->priv;
+	struct kunit_resource *res = kunit_alloc_and_get_resource(
+			&ctx->test,
+			fake_resource_init,
+			fake_resource_free,
+			GFP_KERNEL,
+			ctx);
+
+	kunit_put_resource(res);
+
+	KUNIT_ASSERT_FALSE(test,
+			   kunit_destroy_resource(&ctx->test,
+						  kunit_resource_instance_match,
+						  res->data));
+
+	KUNIT_EXPECT_FALSE(test, ctx->is_resource_initialized);
+	KUNIT_EXPECT_TRUE(test, list_empty(&ctx->test.resources));
+}
+
+static void kunit_resource_test_cleanup_resources(struct kunit *test)
+{
+	int i;
+	struct kunit_test_resource_context *ctx = test->priv;
+	struct kunit_resource *resources[5];
+
+	for (i = 0; i < ARRAY_SIZE(resources); i++) {
+		resources[i] = kunit_alloc_and_get_resource(&ctx->test,
+							    fake_resource_init,
+							    fake_resource_free,
+							    GFP_KERNEL,
+							    ctx);
+		kunit_put_resource(resources[i]);
+	}
+
+	kunit_cleanup(&ctx->test);
+
+	KUNIT_EXPECT_TRUE(test, list_empty(&ctx->test.resources));
+}
+
+static void kunit_resource_test_mark_order(int order_array[],
+					   size_t order_size,
+					   int key)
+{
+	int i;
+
+	for (i = 0; i < order_size && order_array[i]; i++)
+		;
+
+	order_array[i] = key;
+}
+
+#define KUNIT_RESOURCE_TEST_MARK_ORDER(ctx, order_field, key)		       \
+		kunit_resource_test_mark_order(ctx->order_field,	       \
+					       ARRAY_SIZE(ctx->order_field),   \
+					       key)
+
+static int fake_resource_2_init(struct kunit_resource *res, void *context)
+{
+	struct kunit_test_resource_context *ctx = context;
+
+	KUNIT_RESOURCE_TEST_MARK_ORDER(ctx, allocate_order, 2);
+
+	res->data = ctx;
+
+	return 0;
+}
+
+static void fake_resource_2_free(struct kunit_resource *res)
+{
+	struct kunit_test_resource_context *ctx = res->data;
+
+	KUNIT_RESOURCE_TEST_MARK_ORDER(ctx, free_order, 2);
+}
+
+static int fake_resource_1_init(struct kunit_resource *res, void *context)
+{
+	struct kunit_test_resource_context *ctx = context;
+	struct kunit_resource *res2;
+
+	res2 = kunit_alloc_and_get_resource(&ctx->test,
+					    fake_resource_2_init,
+					    fake_resource_2_free,
+					    GFP_KERNEL,
+					    ctx);
+
+	KUNIT_RESOURCE_TEST_MARK_ORDER(ctx, allocate_order, 1);
+
+	res->data = ctx;
+
+	kunit_put_resource(res2);
+
+	return 0;
+}
+
+static void fake_resource_1_free(struct kunit_resource *res)
+{
+	struct kunit_test_resource_context *ctx = res->data;
+
+	KUNIT_RESOURCE_TEST_MARK_ORDER(ctx, free_order, 1);
+}
+
+/*
+ * TODO(brendanhiggins@google.com): replace the arrays that keep track of the
+ * order of allocation and freeing with strict mocks using the IN_SEQUENCE macro
+ * to assert allocation and freeing order when the feature becomes available.
+ */
+static void kunit_resource_test_proper_free_ordering(struct kunit *test)
+{
+	struct kunit_test_resource_context *ctx = test->priv;
+	struct kunit_resource *res;
+
+	/* fake_resource_1 allocates a fake_resource_2 in its init. */
+	res = kunit_alloc_and_get_resource(&ctx->test,
+					   fake_resource_1_init,
+					   fake_resource_1_free,
+					   GFP_KERNEL,
+					   ctx);
+
+	/*
+	 * Since fake_resource_2_init calls KUNIT_RESOURCE_TEST_MARK_ORDER
+	 * before returning to fake_resource_1_init, it should be the first to
+	 * put its key in the allocate_order array.
+	 */
+	KUNIT_EXPECT_EQ(test, ctx->allocate_order[0], 2);
+	KUNIT_EXPECT_EQ(test, ctx->allocate_order[1], 1);
+
+	kunit_put_resource(res);
+
+	kunit_cleanup(&ctx->test);
+
+	/*
+	 * Because fake_resource_2 finishes allocation before fake_resource_1,
+	 * fake_resource_1 should be freed first since it could depend on
+	 * fake_resource_2.
+	 */
+	KUNIT_EXPECT_EQ(test, ctx->free_order[0], 1);
+	KUNIT_EXPECT_EQ(test, ctx->free_order[1], 2);
+}
+
+static void kunit_resource_test_static(struct kunit *test)
+{
+	struct kunit_test_resource_context ctx;
+	struct kunit_resource res;
+
+	KUNIT_EXPECT_EQ(test, kunit_add_resource(test, NULL, NULL, &res, &ctx),
+			0);
+
+	KUNIT_EXPECT_PTR_EQ(test, res.data, (void *)&ctx);
+
+	kunit_cleanup(test);
+
+	KUNIT_EXPECT_TRUE(test, list_empty(&test->resources));
+}
+
+static void kunit_resource_test_named(struct kunit *test)
+{
+	struct kunit_resource res1, res2, *found = NULL;
+	struct kunit_test_resource_context ctx;
+
+	KUNIT_EXPECT_EQ(test,
+			kunit_add_named_resource(test, NULL, NULL, &res1,
+						 "resource_1", &ctx),
+			0);
+	KUNIT_EXPECT_PTR_EQ(test, res1.data, (void *)&ctx);
+
+	KUNIT_EXPECT_EQ(test,
+			kunit_add_named_resource(test, NULL, NULL, &res1,
+						 "resource_1", &ctx),
+			-EEXIST);
+
+	KUNIT_EXPECT_EQ(test,
+			kunit_add_named_resource(test, NULL, NULL, &res2,
+						 "resource_2", &ctx),
+			0);
+
+	found = kunit_find_named_resource(test, "resource_1");
+
+	KUNIT_EXPECT_PTR_EQ(test, found, &res1);
+
+	if (found)
+		kunit_put_resource(&res1);
+
+	KUNIT_EXPECT_EQ(test, kunit_destroy_named_resource(test, "resource_2"),
+			0);
+
+	kunit_cleanup(test);
+
+	KUNIT_EXPECT_TRUE(test, list_empty(&test->resources));
+}
+
+static int kunit_resource_test_init(struct kunit *test)
+{
+	struct kunit_test_resource_context *ctx =
+			kzalloc(sizeof(*ctx), GFP_KERNEL);
+
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
+	test->priv = ctx;
+
+	kunit_init_test(&ctx->test, "test_test_context", NULL);
+
+	return 0;
+}
+
+static void kunit_resource_test_exit(struct kunit *test)
+{
+	struct kunit_test_resource_context *ctx = test->priv;
+
+	kunit_cleanup(&ctx->test);
+	kfree(ctx);
+}
+
+static struct kunit_case kunit_resource_test_cases[] = {
+	KUNIT_CASE(kunit_resource_test_init_resources),
+	KUNIT_CASE(kunit_resource_test_alloc_resource),
+	KUNIT_CASE(kunit_resource_test_destroy_resource),
+	KUNIT_CASE(kunit_resource_test_cleanup_resources),
+	KUNIT_CASE(kunit_resource_test_proper_free_ordering),
+	KUNIT_CASE(kunit_resource_test_static),
+	KUNIT_CASE(kunit_resource_test_named),
+	{}
+};
+
+static struct kunit_suite kunit_resource_test_suite = {
+	.name = "kunit-resource-test",
+	.init = kunit_resource_test_init,
+	.exit = kunit_resource_test_exit,
+	.test_cases = kunit_resource_test_cases,
+};
+
+static void kunit_log_test(struct kunit *test);
+
+static struct kunit_case kunit_log_test_cases[] = {
+	KUNIT_CASE(kunit_log_test),
+	{}
+};
+
+static struct kunit_suite kunit_log_test_suite = {
+	.name = "kunit-log-test",
+	.test_cases = kunit_log_test_cases,
+};
+
+static void kunit_log_test(struct kunit *test)
+{
+	struct kunit_suite *suite = &kunit_log_test_suite;
+
+	kunit_log(KERN_INFO, test, "put this in log.");
+	kunit_log(KERN_INFO, test, "this too.");
+	kunit_log(KERN_INFO, suite, "add to suite log.");
+	kunit_log(KERN_INFO, suite, "along with this.");
+
+#ifdef CONFIG_KUNIT_DEBUGFS
+	KUNIT_EXPECT_NOT_ERR_OR_NULL(test,
+				     strstr(test->log, "put this in log."));
+	KUNIT_EXPECT_NOT_ERR_OR_NULL(test,
+				     strstr(test->log, "this too."));
+	KUNIT_EXPECT_NOT_ERR_OR_NULL(test,
+				     strstr(suite->log, "add to suite log."));
+	KUNIT_EXPECT_NOT_ERR_OR_NULL(test,
+				     strstr(suite->log, "along with this."));
+#else
+	KUNIT_EXPECT_PTR_EQ(test, test->log, (char *)NULL);
+	KUNIT_EXPECT_PTR_EQ(test, suite->log, (char *)NULL);
+#endif
+}
+
+kunit_test_suites(&kunit_try_catch_test_suite, &kunit_resource_test_suite,
+		  &kunit_log_test_suite);
+
+MODULE_LICENSE("GPL v2");
diff --git a/lib/kunit/string-stream-test.c b/lib/kunit/string-stream-test.c
new file mode 100644
index 000000000..110f3a993
--- /dev/null
+++ b/lib/kunit/string-stream-test.c
@@ -0,0 +1,53 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * KUnit test for struct string_stream.
+ *
+ * Copyright (C) 2019, Google LLC.
+ * Author: Brendan Higgins <brendanhiggins@google.com>
+ */
+
+#include <kunit/test.h>
+#include <linux/slab.h>
+
+#include "string-stream.h"
+
+static void string_stream_test_empty_on_creation(struct kunit *test)
+{
+	struct string_stream *stream = alloc_string_stream(test, GFP_KERNEL);
+
+	KUNIT_EXPECT_TRUE(test, string_stream_is_empty(stream));
+}
+
+static void string_stream_test_not_empty_after_add(struct kunit *test)
+{
+	struct string_stream *stream = alloc_string_stream(test, GFP_KERNEL);
+
+	string_stream_add(stream, "Foo");
+
+	KUNIT_EXPECT_FALSE(test, string_stream_is_empty(stream));
+}
+
+static void string_stream_test_get_string(struct kunit *test)
+{
+	struct string_stream *stream = alloc_string_stream(test, GFP_KERNEL);
+	char *output;
+
+	string_stream_add(stream, "Foo");
+	string_stream_add(stream, " %s", "bar");
+
+	output = string_stream_get_string(stream);
+	KUNIT_ASSERT_STREQ(test, output, "Foo bar");
+}
+
+static struct kunit_case string_stream_test_cases[] = {
+	KUNIT_CASE(string_stream_test_empty_on_creation),
+	KUNIT_CASE(string_stream_test_not_empty_after_add),
+	KUNIT_CASE(string_stream_test_get_string),
+	{}
+};
+
+static struct kunit_suite string_stream_test_suite = {
+	.name = "string-stream-test",
+	.test_cases = string_stream_test_cases
+};
+kunit_test_suites(&string_stream_test_suite);
diff --git a/lib/kunit/string-stream.c b/lib/kunit/string-stream.c
new file mode 100644
index 000000000..141789ca8
--- /dev/null
+++ b/lib/kunit/string-stream.c
@@ -0,0 +1,216 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * C++ stream style string builder used in KUnit for building messages.
+ *
+ * Copyright (C) 2019, Google LLC.
+ * Author: Brendan Higgins <brendanhiggins@google.com>
+ */
+
+#include <kunit/test.h>
+#include <linux/list.h>
+#include <linux/slab.h>
+
+#include "string-stream.h"
+
+struct string_stream_fragment_alloc_context {
+	struct kunit *test;
+	int len;
+	gfp_t gfp;
+};
+
+static int string_stream_fragment_init(struct kunit_resource *res,
+				       void *context)
+{
+	struct string_stream_fragment_alloc_context *ctx = context;
+	struct string_stream_fragment *frag;
+
+	frag = kunit_kzalloc(ctx->test, sizeof(*frag), ctx->gfp);
+	if (!frag)
+		return -ENOMEM;
+
+	frag->test = ctx->test;
+	frag->fragment = kunit_kmalloc(ctx->test, ctx->len, ctx->gfp);
+	if (!frag->fragment)
+		return -ENOMEM;
+
+	res->data = frag;
+
+	return 0;
+}
+
+static void string_stream_fragment_free(struct kunit_resource *res)
+{
+	struct string_stream_fragment *frag = res->data;
+
+	list_del(&frag->node);
+	kunit_kfree(frag->test, frag->fragment);
+	kunit_kfree(frag->test, frag);
+}
+
+static struct string_stream_fragment *alloc_string_stream_fragment(
+		struct kunit *test, int len, gfp_t gfp)
+{
+	struct string_stream_fragment_alloc_context context = {
+		.test = test,
+		.len = len,
+		.gfp = gfp
+	};
+
+	return kunit_alloc_resource(test,
+				    string_stream_fragment_init,
+				    string_stream_fragment_free,
+				    gfp,
+				    &context);
+}
+
+static int string_stream_fragment_destroy(struct string_stream_fragment *frag)
+{
+	return kunit_destroy_resource(frag->test,
+				      kunit_resource_instance_match,
+				      frag);
+}
+
+int string_stream_vadd(struct string_stream *stream,
+		       const char *fmt,
+		       va_list args)
+{
+	struct string_stream_fragment *frag_container;
+	int len;
+	va_list args_for_counting;
+
+	/* Make a copy because `vsnprintf` could change it */
+	va_copy(args_for_counting, args);
+
+	/* Need space for null byte. */
+	len = vsnprintf(NULL, 0, fmt, args_for_counting) + 1;
+
+	va_end(args_for_counting);
+
+	frag_container = alloc_string_stream_fragment(stream->test,
+						      len,
+						      stream->gfp);
+	if (!frag_container)
+		return -ENOMEM;
+
+	len = vsnprintf(frag_container->fragment, len, fmt, args);
+	spin_lock(&stream->lock);
+	stream->length += len;
+	list_add_tail(&frag_container->node, &stream->fragments);
+	spin_unlock(&stream->lock);
+
+	return 0;
+}
+
+int string_stream_add(struct string_stream *stream, const char *fmt, ...)
+{
+	va_list args;
+	int result;
+
+	va_start(args, fmt);
+	result = string_stream_vadd(stream, fmt, args);
+	va_end(args);
+
+	return result;
+}
+
+static void string_stream_clear(struct string_stream *stream)
+{
+	struct string_stream_fragment *frag_container, *frag_container_safe;
+
+	spin_lock(&stream->lock);
+	list_for_each_entry_safe(frag_container,
+				 frag_container_safe,
+				 &stream->fragments,
+				 node) {
+		string_stream_fragment_destroy(frag_container);
+	}
+	stream->length = 0;
+	spin_unlock(&stream->lock);
+}
+
+char *string_stream_get_string(struct string_stream *stream)
+{
+	struct string_stream_fragment *frag_container;
+	size_t buf_len = stream->length + 1; /* +1 for null byte. */
+	char *buf;
+
+	buf = kunit_kzalloc(stream->test, buf_len, stream->gfp);
+	if (!buf)
+		return NULL;
+
+	spin_lock(&stream->lock);
+	list_for_each_entry(frag_container, &stream->fragments, node)
+		strlcat(buf, frag_container->fragment, buf_len);
+	spin_unlock(&stream->lock);
+
+	return buf;
+}
+
+int string_stream_append(struct string_stream *stream,
+			 struct string_stream *other)
+{
+	const char *other_content;
+
+	other_content = string_stream_get_string(other);
+
+	if (!other_content)
+		return -ENOMEM;
+
+	return string_stream_add(stream, other_content);
+}
+
+bool string_stream_is_empty(struct string_stream *stream)
+{
+	return list_empty(&stream->fragments);
+}
+
+struct string_stream_alloc_context {
+	struct kunit *test;
+	gfp_t gfp;
+};
+
+static int string_stream_init(struct kunit_resource *res, void *context)
+{
+	struct string_stream *stream;
+	struct string_stream_alloc_context *ctx = context;
+
+	stream = kunit_kzalloc(ctx->test, sizeof(*stream), ctx->gfp);
+	if (!stream)
+		return -ENOMEM;
+
+	res->data = stream;
+	stream->gfp = ctx->gfp;
+	stream->test = ctx->test;
+	INIT_LIST_HEAD(&stream->fragments);
+	spin_lock_init(&stream->lock);
+
+	return 0;
+}
+
+static void string_stream_free(struct kunit_resource *res)
+{
+	struct string_stream *stream = res->data;
+
+	string_stream_clear(stream);
+}
+
+struct string_stream *alloc_string_stream(struct kunit *test, gfp_t gfp)
+{
+	struct string_stream_alloc_context context = {
+		.test = test,
+		.gfp = gfp
+	};
+
+	return kunit_alloc_resource(test,
+				    string_stream_init,
+				    string_stream_free,
+				    gfp,
+				    &context);
+}
+
+int string_stream_destroy(struct string_stream *stream)
+{
+	return kunit_destroy_resource(stream->test,
+				      kunit_resource_instance_match,
+				      stream);
+}
diff --git a/lib/kunit/string-stream.h b/lib/kunit/string-stream.h
new file mode 100644
index 000000000..fe98a00b7
--- /dev/null
+++ b/lib/kunit/string-stream.h
@@ -0,0 +1,51 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * C++ stream style string builder used in KUnit for building messages.
+ *
+ * Copyright (C) 2019, Google LLC.
+ * Author: Brendan Higgins <brendanhiggins@google.com>
+ */
+
+#ifndef _KUNIT_STRING_STREAM_H
+#define _KUNIT_STRING_STREAM_H
+
+#include <linux/spinlock.h>
+#include <linux/types.h>
+#include <stdarg.h>
+
+struct string_stream_fragment {
+	struct kunit *test;
+	struct list_head node;
+	char *fragment;
+};
+
+struct string_stream {
+	size_t length;
+	struct list_head fragments;
+	/* length and fragments are protected by this lock */
+	spinlock_t lock;
+	struct kunit *test;
+	gfp_t gfp;
+};
+
+struct kunit;
+
+struct string_stream *alloc_string_stream(struct kunit *test, gfp_t gfp);
+
+int __printf(2, 3) string_stream_add(struct string_stream *stream,
+				     const char *fmt, ...);
+
+int string_stream_vadd(struct string_stream *stream,
+		       const char *fmt,
+		       va_list args);
+
+char *string_stream_get_string(struct string_stream *stream);
+
+int string_stream_append(struct string_stream *stream,
+			 struct string_stream *other);
+
+bool string_stream_is_empty(struct string_stream *stream);
+
+int string_stream_destroy(struct string_stream *stream);
+
+#endif /* _KUNIT_STRING_STREAM_H */
diff --git a/lib/kunit/test.c b/lib/kunit/test.c
new file mode 100644
index 000000000..750704abe
--- /dev/null
+++ b/lib/kunit/test.c
@@ -0,0 +1,614 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Base unit test (KUnit) API.
+ *
+ * Copyright (C) 2019, Google LLC.
+ * Author: Brendan Higgins <brendanhiggins@google.com>
+ */
+
+#include <kunit/test.h>
+#include <linux/kernel.h>
+#include <linux/kref.h>
+#include <linux/sched/debug.h>
+#include <linux/sched.h>
+
+#include "debugfs.h"
+#include "string-stream.h"
+#include "try-catch-impl.h"
+
+/*
+ * Append formatted message to log, size of which is limited to
+ * KUNIT_LOG_SIZE bytes (including null terminating byte).
+ */
+void kunit_log_append(char *log, const char *fmt, ...)
+{
+	char line[KUNIT_LOG_SIZE];
+	va_list args;
+	int len_left;
+
+	if (!log)
+		return;
+
+	len_left = KUNIT_LOG_SIZE - strlen(log) - 1;
+	if (len_left <= 0)
+		return;
+
+	va_start(args, fmt);
+	vsnprintf(line, sizeof(line), fmt, args);
+	va_end(args);
+
+	strncat(log, line, len_left);
+}
+EXPORT_SYMBOL_GPL(kunit_log_append);
+
+size_t kunit_suite_num_test_cases(struct kunit_suite *suite)
+{
+	struct kunit_case *test_case;
+	size_t len = 0;
+
+	kunit_suite_for_each_test_case(suite, test_case)
+		len++;
+
+	return len;
+}
+EXPORT_SYMBOL_GPL(kunit_suite_num_test_cases);
+
+static void kunit_print_subtest_start(struct kunit_suite *suite)
+{
+	kunit_log(KERN_INFO, suite, KUNIT_SUBTEST_INDENT "# Subtest: %s",
+		  suite->name);
+	kunit_log(KERN_INFO, suite, KUNIT_SUBTEST_INDENT "1..%zd",
+		  kunit_suite_num_test_cases(suite));
+}
+
+static void kunit_print_ok_not_ok(void *test_or_suite,
+				  bool is_test,
+				  bool is_ok,
+				  size_t test_number,
+				  const char *description)
+{
+	struct kunit_suite *suite = is_test ? NULL : test_or_suite;
+	struct kunit *test = is_test ? test_or_suite : NULL;
+
+	/*
+	 * We do not log the test suite results as doing so would
+	 * mean debugfs display would consist of the test suite
+	 * description and status prior to individual test results.
+	 * Hence directly printk the suite status, and we will
+	 * separately seq_printf() the suite status for the debugfs
+	 * representation.
+	 */
+	if (suite)
+		pr_info("%s %zd - %s\n",
+			kunit_status_to_string(is_ok),
+			test_number, description);
+	else
+		kunit_log(KERN_INFO, test, KUNIT_SUBTEST_INDENT "%s %zd - %s",
+			  kunit_status_to_string(is_ok),
+			  test_number, description);
+}
+
+bool kunit_suite_has_succeeded(struct kunit_suite *suite)
+{
+	const struct kunit_case *test_case;
+
+	kunit_suite_for_each_test_case(suite, test_case) {
+		if (!test_case->success)
+			return false;
+	}
+
+	return true;
+}
+EXPORT_SYMBOL_GPL(kunit_suite_has_succeeded);
+
+static void kunit_print_subtest_end(struct kunit_suite *suite)
+{
+	static size_t kunit_suite_counter = 1;
+
+	kunit_print_ok_not_ok((void *)suite, false,
+			      kunit_suite_has_succeeded(suite),
+			      kunit_suite_counter++,
+			      suite->name);
+}
+
+unsigned int kunit_test_case_num(struct kunit_suite *suite,
+				 struct kunit_case *test_case)
+{
+	struct kunit_case *tc;
+	unsigned int i = 1;
+
+	kunit_suite_for_each_test_case(suite, tc) {
+		if (tc == test_case)
+			return i;
+		i++;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(kunit_test_case_num);
+
+static void kunit_print_string_stream(struct kunit *test,
+				      struct string_stream *stream)
+{
+	struct string_stream_fragment *fragment;
+	char *buf;
+
+	if (string_stream_is_empty(stream))
+		return;
+
+	buf = string_stream_get_string(stream);
+	if (!buf) {
+		kunit_err(test,
+			  "Could not allocate buffer, dumping stream:\n");
+		list_for_each_entry(fragment, &stream->fragments, node) {
+			kunit_err(test, "%s", fragment->fragment);
+		}
+		kunit_err(test, "\n");
+	} else {
+		kunit_err(test, "%s", buf);
+		kunit_kfree(test, buf);
+	}
+}
+
+static void kunit_fail(struct kunit *test, struct kunit_assert *assert)
+{
+	struct string_stream *stream;
+
+	kunit_set_failure(test);
+
+	stream = alloc_string_stream(test, GFP_KERNEL);
+	if (!stream) {
+		WARN(true,
+		     "Could not allocate stream to print failed assertion in %s:%d\n",
+		     assert->file,
+		     assert->line);
+		return;
+	}
+
+	assert->format(assert, stream);
+
+	kunit_print_string_stream(test, stream);
+
+	WARN_ON(string_stream_destroy(stream));
+}
+
+static void __noreturn kunit_abort(struct kunit *test)
+{
+	kunit_try_catch_throw(&test->try_catch); /* Does not return. */
+
+	/*
+	 * Throw could not abort from test.
+	 *
+	 * XXX: we should never reach this line! As kunit_try_catch_throw is
+	 * marked __noreturn.
+	 */
+	WARN_ONCE(true, "Throw could not abort from test!\n");
+}
+
+void kunit_do_assertion(struct kunit *test,
+			struct kunit_assert *assert,
+			bool pass,
+			const char *fmt, ...)
+{
+	va_list args;
+
+	if (pass)
+		return;
+
+	va_start(args, fmt);
+
+	assert->message.fmt = fmt;
+	assert->message.va = &args;
+
+	kunit_fail(test, assert);
+
+	va_end(args);
+
+	if (assert->type == KUNIT_ASSERTION)
+		kunit_abort(test);
+}
+EXPORT_SYMBOL_GPL(kunit_do_assertion);
+
+void kunit_init_test(struct kunit *test, const char *name, char *log)
+{
+	spin_lock_init(&test->lock);
+	INIT_LIST_HEAD(&test->resources);
+	test->name = name;
+	test->log = log;
+	if (test->log)
+		test->log[0] = '\0';
+	test->success = true;
+}
+EXPORT_SYMBOL_GPL(kunit_init_test);
+
+/*
+ * Initializes and runs test case. Does not clean up or do post validations.
+ */
+static void kunit_run_case_internal(struct kunit *test,
+				    struct kunit_suite *suite,
+				    struct kunit_case *test_case)
+{
+	if (suite->init) {
+		int ret;
+
+		ret = suite->init(test);
+		if (ret) {
+			kunit_err(test, "failed to initialize: %d\n", ret);
+			kunit_set_failure(test);
+			return;
+		}
+	}
+
+	test_case->run_case(test);
+}
+
+static void kunit_case_internal_cleanup(struct kunit *test)
+{
+	kunit_cleanup(test);
+}
+
+/*
+ * Performs post validations and cleanup after a test case was run.
+ * XXX: Should ONLY BE CALLED AFTER kunit_run_case_internal!
+ */
+static void kunit_run_case_cleanup(struct kunit *test,
+				   struct kunit_suite *suite)
+{
+	if (suite->exit)
+		suite->exit(test);
+
+	kunit_case_internal_cleanup(test);
+}
+
+struct kunit_try_catch_context {
+	struct kunit *test;
+	struct kunit_suite *suite;
+	struct kunit_case *test_case;
+};
+
+static void kunit_try_run_case(void *data)
+{
+	struct kunit_try_catch_context *ctx = data;
+	struct kunit *test = ctx->test;
+	struct kunit_suite *suite = ctx->suite;
+	struct kunit_case *test_case = ctx->test_case;
+
+#if (IS_ENABLED(CONFIG_KASAN) && IS_ENABLED(CONFIG_KUNIT))
+	current->kunit_test = test;
+#endif /* IS_ENABLED(CONFIG_KASAN) && IS_ENABLED(CONFIG_KUNIT) */
+
+	/*
+	 * kunit_run_case_internal may encounter a fatal error; if it does,
+	 * abort will be called, this thread will exit, and finally the parent
+	 * thread will resume control and handle any necessary clean up.
+	 */
+	kunit_run_case_internal(test, suite, test_case);
+	/* This line may never be reached. */
+	kunit_run_case_cleanup(test, suite);
+}
+
+static void kunit_catch_run_case(void *data)
+{
+	struct kunit_try_catch_context *ctx = data;
+	struct kunit *test = ctx->test;
+	struct kunit_suite *suite = ctx->suite;
+	int try_exit_code = kunit_try_catch_get_result(&test->try_catch);
+
+	if (try_exit_code) {
+		kunit_set_failure(test);
+		/*
+		 * Test case could not finish, we have no idea what state it is
+		 * in, so don't do clean up.
+		 */
+		if (try_exit_code == -ETIMEDOUT) {
+			kunit_err(test, "test case timed out\n");
+		/*
+		 * Unknown internal error occurred preventing test case from
+		 * running, so there is nothing to clean up.
+		 */
+		} else {
+			kunit_err(test, "internal error occurred preventing test case from running: %d\n",
+				  try_exit_code);
+		}
+		return;
+	}
+
+	/*
+	 * Test case was run, but aborted. It is the test case's business as to
+	 * whether it failed or not, we just need to clean up.
+	 */
+	kunit_run_case_cleanup(test, suite);
+}
+
+/*
+ * Performs all logic to run a test case. It also catches most errors that
+ * occur in a test case and reports them as failures.
+ */
+static void kunit_run_case_catch_errors(struct kunit_suite *suite,
+					struct kunit_case *test_case)
+{
+	struct kunit_try_catch_context context;
+	struct kunit_try_catch *try_catch;
+	struct kunit test;
+
+	kunit_init_test(&test, test_case->name, test_case->log);
+	try_catch = &test.try_catch;
+
+	kunit_try_catch_init(try_catch,
+			     &test,
+			     kunit_try_run_case,
+			     kunit_catch_run_case);
+	context.test = &test;
+	context.suite = suite;
+	context.test_case = test_case;
+	kunit_try_catch_run(try_catch, &context);
+
+	test_case->success = test.success;
+
+	kunit_print_ok_not_ok(&test, true, test_case->success,
+			      kunit_test_case_num(suite, test_case),
+			      test_case->name);
+}
+
+int kunit_run_tests(struct kunit_suite *suite)
+{
+	struct kunit_case *test_case;
+
+	kunit_print_subtest_start(suite);
+
+	kunit_suite_for_each_test_case(suite, test_case)
+		kunit_run_case_catch_errors(suite, test_case);
+
+	kunit_print_subtest_end(suite);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(kunit_run_tests);
+
+static void kunit_init_suite(struct kunit_suite *suite)
+{
+	kunit_debugfs_create_suite(suite);
+}
+
+int __kunit_test_suites_init(struct kunit_suite * const * const suites)
+{
+	unsigned int i;
+
+	for (i = 0; suites[i] != NULL; i++) {
+		kunit_init_suite(suites[i]);
+		kunit_run_tests(suites[i]);
+	}
+	return 0;
+}
+EXPORT_SYMBOL_GPL(__kunit_test_suites_init);
+
+static void kunit_exit_suite(struct kunit_suite *suite)
+{
+	kunit_debugfs_destroy_suite(suite);
+}
+
+void __kunit_test_suites_exit(struct kunit_suite **suites)
+{
+	unsigned int i;
+
+	for (i = 0; suites[i] != NULL; i++)
+		kunit_exit_suite(suites[i]);
+}
+EXPORT_SYMBOL_GPL(__kunit_test_suites_exit);
+
+/*
+ * Used for static resources and when a kunit_resource * has been created by
+ * kunit_alloc_resource().  When an init function is supplied, @data is passed
+ * into the init function; otherwise, we simply set the resource data field to
+ * the data value passed in.
+ */
+int kunit_add_resource(struct kunit *test,
+		       kunit_resource_init_t init,
+		       kunit_resource_free_t free,
+		       struct kunit_resource *res,
+		       void *data)
+{
+	int ret = 0;
+
+	res->free = free;
+	kref_init(&res->refcount);
+
+	if (init) {
+		ret = init(res, data);
+		if (ret)
+			return ret;
+	} else {
+		res->data = data;
+	}
+
+	spin_lock(&test->lock);
+	list_add_tail(&res->node, &test->resources);
+	/* refcount for list is established by kref_init() */
+	spin_unlock(&test->lock);
+
+	return ret;
+}
+EXPORT_SYMBOL_GPL(kunit_add_resource);
+
+int kunit_add_named_resource(struct kunit *test,
+			     kunit_resource_init_t init,
+			     kunit_resource_free_t free,
+			     struct kunit_resource *res,
+			     const char *name,
+			     void *data)
+{
+	struct kunit_resource *existing;
+
+	if (!name)
+		return -EINVAL;
+
+	existing = kunit_find_named_resource(test, name);
+	if (existing) {
+		kunit_put_resource(existing);
+		return -EEXIST;
+	}
+
+	res->name = name;
+
+	return kunit_add_resource(test, init, free, res, data);
+}
+EXPORT_SYMBOL_GPL(kunit_add_named_resource);
+
+struct kunit_resource *kunit_alloc_and_get_resource(struct kunit *test,
+						    kunit_resource_init_t init,
+						    kunit_resource_free_t free,
+						    gfp_t internal_gfp,
+						    void *data)
+{
+	struct kunit_resource *res;
+	int ret;
+
+	res = kzalloc(sizeof(*res), internal_gfp);
+	if (!res)
+		return NULL;
+
+	ret = kunit_add_resource(test, init, free, res, data);
+	if (!ret) {
+		/*
+		 * bump refcount for get; kunit_resource_put() should be called
+		 * when done.
+		 */
+		kunit_get_resource(res);
+		return res;
+	}
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(kunit_alloc_and_get_resource);
+
+void kunit_remove_resource(struct kunit *test, struct kunit_resource *res)
+{
+	spin_lock(&test->lock);
+	list_del(&res->node);
+	spin_unlock(&test->lock);
+	kunit_put_resource(res);
+}
+EXPORT_SYMBOL_GPL(kunit_remove_resource);
+
+int kunit_destroy_resource(struct kunit *test, kunit_resource_match_t match,
+			   void *match_data)
+{
+	struct kunit_resource *res = kunit_find_resource(test, match,
+							 match_data);
+
+	if (!res)
+		return -ENOENT;
+
+	kunit_remove_resource(test, res);
+
+	/* We have a reference also via _find(); drop it. */
+	kunit_put_resource(res);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(kunit_destroy_resource);
+
+struct kunit_kmalloc_params {
+	size_t size;
+	gfp_t gfp;
+};
+
+static int kunit_kmalloc_init(struct kunit_resource *res, void *context)
+{
+	struct kunit_kmalloc_params *params = context;
+
+	res->data = kmalloc(params->size, params->gfp);
+	if (!res->data)
+		return -ENOMEM;
+
+	return 0;
+}
+
+static void kunit_kmalloc_free(struct kunit_resource *res)
+{
+	kfree(res->data);
+}
+
+void *kunit_kmalloc(struct kunit *test, size_t size, gfp_t gfp)
+{
+	struct kunit_kmalloc_params params = {
+		.size = size,
+		.gfp = gfp
+	};
+
+	return kunit_alloc_resource(test,
+				    kunit_kmalloc_init,
+				    kunit_kmalloc_free,
+				    gfp,
+				    &params);
+}
+EXPORT_SYMBOL_GPL(kunit_kmalloc);
+
+void kunit_kfree(struct kunit *test, const void *ptr)
+{
+	struct kunit_resource *res;
+
+	res = kunit_find_resource(test, kunit_resource_instance_match,
+				  (void *)ptr);
+
+	/*
+	 * Removing the resource from the list of resources drops the
+	 * reference count to 1; the final put will trigger the free.
+	 */
+	kunit_remove_resource(test, res);
+
+	kunit_put_resource(res);
+
+}
+EXPORT_SYMBOL_GPL(kunit_kfree);
+
+void kunit_cleanup(struct kunit *test)
+{
+	struct kunit_resource *res;
+
+	/*
+	 * test->resources is a stack - each allocation must be freed in the
+	 * reverse order from which it was added since one resource may depend
+	 * on another for its entire lifetime.
+	 * Also, we cannot use the normal list_for_each constructs, even the
+	 * safe ones because *arbitrary* nodes may be deleted when
+	 * kunit_resource_free is called; the list_for_each_safe variants only
+	 * protect against the current node being deleted, not the next.
+	 */
+	while (true) {
+		spin_lock(&test->lock);
+		if (list_empty(&test->resources)) {
+			spin_unlock(&test->lock);
+			break;
+		}
+		res = list_last_entry(&test->resources,
+				      struct kunit_resource,
+				      node);
+		/*
+		 * Need to unlock here as a resource may remove another
+		 * resource, and this can't happen if the test->lock
+		 * is held.
+		 */
+		spin_unlock(&test->lock);
+		kunit_remove_resource(test, res);
+	}
+#if (IS_ENABLED(CONFIG_KASAN) && IS_ENABLED(CONFIG_KUNIT))
+	current->kunit_test = NULL;
+#endif /* IS_ENABLED(CONFIG_KASAN) && IS_ENABLED(CONFIG_KUNIT)*/
+}
+EXPORT_SYMBOL_GPL(kunit_cleanup);
+
+static int __init kunit_init(void)
+{
+	kunit_debugfs_init();
+
+	return 0;
+}
+late_initcall(kunit_init);
+
+static void __exit kunit_exit(void)
+{
+	kunit_debugfs_cleanup();
+}
+module_exit(kunit_exit);
+
+MODULE_LICENSE("GPL v2");
diff --git a/lib/kunit/try-catch-impl.h b/lib/kunit/try-catch-impl.h
new file mode 100644
index 000000000..203ba6a5e
--- /dev/null
+++ b/lib/kunit/try-catch-impl.h
@@ -0,0 +1,27 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Internal kunit try catch implementation to be shared with tests.
+ *
+ * Copyright (C) 2019, Google LLC.
+ * Author: Brendan Higgins <brendanhiggins@google.com>
+ */
+
+#ifndef _KUNIT_TRY_CATCH_IMPL_H
+#define _KUNIT_TRY_CATCH_IMPL_H
+
+#include <kunit/try-catch.h>
+#include <linux/types.h>
+
+struct kunit;
+
+static inline void kunit_try_catch_init(struct kunit_try_catch *try_catch,
+					struct kunit *test,
+					kunit_try_catch_func_t try,
+					kunit_try_catch_func_t catch)
+{
+	try_catch->test = test;
+	try_catch->try = try;
+	try_catch->catch = catch;
+}
+
+#endif /* _KUNIT_TRY_CATCH_IMPL_H */
diff --git a/lib/kunit/try-catch.c b/lib/kunit/try-catch.c
new file mode 100644
index 000000000..71e5c5853
--- /dev/null
+++ b/lib/kunit/try-catch.c
@@ -0,0 +1,97 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * An API to allow a function, that may fail, to be executed, and recover in a
+ * controlled manner.
+ *
+ * Copyright (C) 2019, Google LLC.
+ * Author: Brendan Higgins <brendanhiggins@google.com>
+ */
+
+#include <kunit/test.h>
+#include <linux/completion.h>
+#include <linux/kernel.h>
+#include <linux/kthread.h>
+
+#include "try-catch-impl.h"
+
+void __noreturn kunit_try_catch_throw(struct kunit_try_catch *try_catch)
+{
+	try_catch->try_result = -EFAULT;
+	complete_and_exit(try_catch->try_completion, -EFAULT);
+}
+EXPORT_SYMBOL_GPL(kunit_try_catch_throw);
+
+static int kunit_generic_run_threadfn_adapter(void *data)
+{
+	struct kunit_try_catch *try_catch = data;
+
+	try_catch->try(try_catch->context);
+
+	complete_and_exit(try_catch->try_completion, 0);
+}
+
+static unsigned long kunit_test_timeout(void)
+{
+	/*
+	 * TODO(brendanhiggins@google.com): We should probably have some type of
+	 * variable timeout here. The only question is what that timeout value
+	 * should be.
+	 *
+	 * The intention has always been, at some point, to be able to label
+	 * tests with some type of size bucket (unit/small, integration/medium,
+	 * large/system/end-to-end, etc), where each size bucket would get a
+	 * default timeout value kind of like what Bazel does:
+	 * https://docs.bazel.build/versions/master/be/common-definitions.html#test.size
+	 * There is still some debate to be had on exactly how we do this. (For
+	 * one, we probably want to have some sort of test runner level
+	 * timeout.)
+	 *
+	 * For more background on this topic, see:
+	 * https://mike-bland.com/2011/11/01/small-medium-large.html
+	 *
+	 * If tests timeout due to exceeding sysctl_hung_task_timeout_secs,
+	 * the task will be killed and an oops generated.
+	 */
+	return 300 * msecs_to_jiffies(MSEC_PER_SEC); /* 5 min */
+}
+
+void kunit_try_catch_run(struct kunit_try_catch *try_catch, void *context)
+{
+	DECLARE_COMPLETION_ONSTACK(try_completion);
+	struct kunit *test = try_catch->test;
+	struct task_struct *task_struct;
+	int exit_code, time_remaining;
+
+	try_catch->context = context;
+	try_catch->try_completion = &try_completion;
+	try_catch->try_result = 0;
+	task_struct = kthread_run(kunit_generic_run_threadfn_adapter,
+				  try_catch,
+				  "kunit_try_catch_thread");
+	if (IS_ERR(task_struct)) {
+		try_catch->catch(try_catch->context);
+		return;
+	}
+
+	time_remaining = wait_for_completion_timeout(&try_completion,
+						     kunit_test_timeout());
+	if (time_remaining == 0) {
+		kunit_err(test, "try timed out\n");
+		try_catch->try_result = -ETIMEDOUT;
+	}
+
+	exit_code = try_catch->try_result;
+
+	if (!exit_code)
+		return;
+
+	if (exit_code == -EFAULT)
+		try_catch->try_result = 0;
+	else if (exit_code == -EINTR)
+		kunit_err(test, "wake_up_process() was never called\n");
+	else if (exit_code)
+		kunit_err(test, "Unknown error: %d\n", exit_code);
+
+	try_catch->catch(try_catch->context);
+}
+EXPORT_SYMBOL_GPL(kunit_try_catch_run);