From 56778b49c9a2cbc32c6b0fbd3ba1a9d64192d3af Mon Sep 17 00:00:00 2001 From: David Gow Date: Tue, 28 Nov 2023 15:24:05 +0800 Subject: kunit: Add a macro to wrap a deferred action function KUnit's deferred action API accepts a void(*)(void *) function pointer which is called when the test is exited. However, we very frequently want to use existing functions which accept a single pointer, but which may not be of type void*. While this is probably dodgy enough to be on the wrong side of the C standard, it's been often used for similar callbacks, and gcc's -Wcast-function-type seems to ignore cases where the only difference is the type of the argument, assuming it's compatible (i.e., they're both pointers to data). However, clang 16 has introduced -Wcast-function-type-strict, which no longer permits any deviation in function pointer type. This seems to be because it'd break CFI, which validates the type of function calls. This rather ruins our attempts to cast functions to defer them, and leaves us with a few options. The one we've chosen is to implement a macro which will generate a wrapper function which accepts a void*, and casts the argument to the appropriate type. For example, if you were trying to wrap: void foo_close(struct foo *handle); you could use: KUNIT_DEFINE_ACTION_WRAPPER(kunit_action_foo_close, foo_close, struct foo *); This would create a new kunit_action_foo_close() function, of type kunit_action_t, which could be passed into kunit_add_action() and similar functions. In addition to defining this macro, update KUnit and its tests to use it. Link: https://github.com/ClangBuiltLinux/linux/issues/1750 Reviewed-by: Nathan Chancellor Tested-by: Nathan Chancellor Acked-by: Daniel Vetter Reviewed-by: Maxime Ripard Signed-off-by: David Gow Signed-off-by: Shuah Khan --- include/kunit/resource.h | 21 +++++++++++++++++++++ 1 file changed, 21 insertions(+) (limited to 'include') diff --git a/include/kunit/resource.h b/include/kunit/resource.h index c7383e90f5c9..4ad69a2642a5 100644 --- a/include/kunit/resource.h +++ b/include/kunit/resource.h @@ -390,6 +390,27 @@ void kunit_remove_resource(struct kunit *test, struct kunit_resource *res); /* A 'deferred action' function to be used with kunit_add_action. */ typedef void (kunit_action_t)(void *); +/** + * KUNIT_DEFINE_ACTION_WRAPPER() - Wrap a function for use as a deferred action. + * + * @wrapper: The name of the new wrapper function define. + * @orig: The original function to wrap. + * @arg_type: The type of the argument accepted by @orig. + * + * Defines a wrapper for a function which accepts a single, pointer-sized + * argument. This wrapper can then be passed to kunit_add_action() and + * similar. This should be used in preference to casting a function + * directly to kunit_action_t, as casting function pointers will break + * control flow integrity (CFI), leading to crashes. + */ +#define KUNIT_DEFINE_ACTION_WRAPPER(wrapper, orig, arg_type) \ + static void wrapper(void *in) \ + { \ + arg_type arg = (arg_type)in; \ + orig(arg); \ + } + + /** * kunit_add_action() - Call a function when the test ends. * @test: Test case to associate the action with. -- cgit From 69dfdce1c5161a37a14720e5f6f62a36e387aa33 Mon Sep 17 00:00:00 2001 From: Rae Moar Date: Wed, 13 Dec 2023 19:44:16 +0000 Subject: kunit: move KUNIT_TABLE out of INIT_DATA Alter the linker section of KUNIT_TABLE to move it out of INIT_DATA and into DATA_DATA. Data for KUnit tests does not need to be in the init section. In order to run tests again after boot the KUnit data cannot be labeled as init data as the kernel could write over it. Add a KUNIT_INIT_TABLE in the next patch for KUnit tests that test init data/functions. Reviewed-by: David Gow Signed-off-by: Rae Moar Signed-off-by: Shuah Khan --- include/asm-generic/vmlinux.lds.h | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'include') diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index bae0fe4d499b..1107905d37fc 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -370,7 +370,8 @@ BRANCH_PROFILE() \ TRACE_PRINTKS() \ BPF_RAW_TP() \ - TRACEPOINT_STR() + TRACEPOINT_STR() \ + KUNIT_TABLE() /* * Data section helpers @@ -699,8 +700,7 @@ THERMAL_TABLE(governor) \ EARLYCON_TABLE() \ LSM_TABLE() \ - EARLY_LSM_TABLE() \ - KUNIT_TABLE() + EARLY_LSM_TABLE() #define INIT_TEXT \ *(.init.text .init.text.*) \ -- cgit From d81f0d7b8b23ec79f80be602ed6129ded27862e8 Mon Sep 17 00:00:00 2001 From: Rae Moar Date: Wed, 13 Dec 2023 19:44:17 +0000 Subject: kunit: add KUNIT_INIT_TABLE to init linker section Add KUNIT_INIT_TABLE to the INIT_DATA linker section. Alter the KUnit macros to create init tests: kunit_test_init_section_suites Update lib/kunit/executor.c to run both the suites in KUNIT_TABLE and KUNIT_INIT_TABLE. Reviewed-by: David Gow Signed-off-by: Rae Moar Signed-off-by: Shuah Khan --- include/asm-generic/vmlinux.lds.h | 9 +++++- include/kunit/test.h | 30 +++++++++++------- include/linux/module.h | 2 ++ kernel/module/main.c | 3 ++ lib/kunit/executor.c | 64 +++++++++++++++++++++++++++++++++++---- lib/kunit/test.c | 26 +++++++++++----- 6 files changed, 109 insertions(+), 25 deletions(-) (limited to 'include') diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h index 1107905d37fc..5dd3a61d673d 100644 --- a/include/asm-generic/vmlinux.lds.h +++ b/include/asm-generic/vmlinux.lds.h @@ -700,7 +700,8 @@ THERMAL_TABLE(governor) \ EARLYCON_TABLE() \ LSM_TABLE() \ - EARLY_LSM_TABLE() + EARLY_LSM_TABLE() \ + KUNIT_INIT_TABLE() #define INIT_TEXT \ *(.init.text .init.text.*) \ @@ -926,6 +927,12 @@ . = ALIGN(8); \ BOUNDED_SECTION_POST_LABEL(.kunit_test_suites, __kunit_suites, _start, _end) +/* Alignment must be consistent with (kunit_suite *) in include/kunit/test.h */ +#define KUNIT_INIT_TABLE() \ + . = ALIGN(8); \ + BOUNDED_SECTION_POST_LABEL(.kunit_init_test_suites, \ + __kunit_init_suites, _start, _end) + #ifdef CONFIG_BLK_DEV_INITRD #define INIT_RAM_FS \ . = ALIGN(4); \ diff --git a/include/kunit/test.h b/include/kunit/test.h index 20ed9f9275c9..fe79cd736e94 100644 --- a/include/kunit/test.h +++ b/include/kunit/test.h @@ -337,6 +337,9 @@ void __kunit_test_suites_exit(struct kunit_suite **suites, int num_suites); void kunit_exec_run_tests(struct kunit_suite_set *suite_set, bool builtin); void kunit_exec_list_tests(struct kunit_suite_set *suite_set, bool include_attr); +struct kunit_suite_set kunit_merge_suite_sets(struct kunit_suite_set init_suite_set, + struct kunit_suite_set suite_set); + #if IS_BUILTIN(CONFIG_KUNIT) int kunit_run_all_tests(void); #else @@ -371,6 +374,11 @@ static inline int kunit_run_all_tests(void) #define kunit_test_suite(suite) kunit_test_suites(&suite) +#define __kunit_init_test_suites(unique_array, ...) \ + static struct kunit_suite *unique_array[] \ + __aligned(sizeof(struct kunit_suite *)) \ + __used __section(".kunit_init_test_suites") = { __VA_ARGS__ } + /** * kunit_test_init_section_suites() - used to register one or more &struct * kunit_suite containing init functions or @@ -378,21 +386,21 @@ static inline int kunit_run_all_tests(void) * * @__suites: a statically allocated list of &struct kunit_suite. * - * This functions identically as kunit_test_suites() except that it suppresses - * modpost warnings for referencing functions marked __init or data marked - * __initdata; this is OK because currently KUnit only runs tests upon boot - * during the init phase or upon loading a module during the init phase. + * This functions similar to kunit_test_suites() except that it compiles the + * list of suites during init phase. + * + * This macro also suffixes the array and suite declarations it makes with + * _probe; so that modpost suppresses warnings about referencing init data + * for symbols named in this manner. * - * NOTE TO KUNIT DEVS: If we ever allow KUnit tests to be run after boot, these - * tests must be excluded. + * Note: these init tests are not able to be run after boot so there is no + * "run" debugfs file generated for these tests. * - * The only thing this macro does that's different from kunit_test_suites is - * that it suffixes the array and suite declarations it makes with _probe; - * modpost suppresses warnings about referencing init data for symbols named in - * this manner. + * Also, do not mark the suite or test case structs with __initdata because + * they will be used after the init phase with debugfs. */ #define kunit_test_init_section_suites(__suites...) \ - __kunit_test_suites(CONCATENATE(__UNIQUE_ID(array), _probe), \ + __kunit_init_test_suites(CONCATENATE(__UNIQUE_ID(array), _probe), \ ##__suites) #define kunit_test_init_section_suite(suite) \ diff --git a/include/linux/module.h b/include/linux/module.h index a98e188cf37b..9cd0009bd050 100644 --- a/include/linux/module.h +++ b/include/linux/module.h @@ -540,6 +540,8 @@ struct module { struct static_call_site *static_call_sites; #endif #if IS_ENABLED(CONFIG_KUNIT) + int num_kunit_init_suites; + struct kunit_suite **kunit_init_suites; int num_kunit_suites; struct kunit_suite **kunit_suites; #endif diff --git a/kernel/module/main.c b/kernel/module/main.c index 98fedfdb8db5..36681911c05a 100644 --- a/kernel/module/main.c +++ b/kernel/module/main.c @@ -2199,6 +2199,9 @@ static int find_module_sections(struct module *mod, struct load_info *info) mod->kunit_suites = section_objs(info, ".kunit_test_suites", sizeof(*mod->kunit_suites), &mod->num_kunit_suites); + mod->kunit_init_suites = section_objs(info, ".kunit_init_test_suites", + sizeof(*mod->kunit_init_suites), + &mod->num_kunit_init_suites); #endif mod->extable = section_objs(info, "__ex_table", diff --git a/lib/kunit/executor.c b/lib/kunit/executor.c index 1236b3cd2fbb..847329c51e91 100644 --- a/lib/kunit/executor.c +++ b/lib/kunit/executor.c @@ -12,6 +12,8 @@ */ extern struct kunit_suite * const __kunit_suites_start[]; extern struct kunit_suite * const __kunit_suites_end[]; +extern struct kunit_suite * const __kunit_init_suites_start[]; +extern struct kunit_suite * const __kunit_init_suites_end[]; static char *action_param; @@ -292,6 +294,33 @@ void kunit_exec_list_tests(struct kunit_suite_set *suite_set, bool include_attr) } } +struct kunit_suite_set kunit_merge_suite_sets(struct kunit_suite_set init_suite_set, + struct kunit_suite_set suite_set) +{ + struct kunit_suite_set total_suite_set = {NULL, NULL}; + struct kunit_suite **total_suite_start = NULL; + size_t init_num_suites, num_suites, suite_size; + + init_num_suites = init_suite_set.end - init_suite_set.start; + num_suites = suite_set.end - suite_set.start; + suite_size = sizeof(suite_set.start); + + /* Allocate memory for array of all kunit suites */ + total_suite_start = kmalloc_array(init_num_suites + num_suites, suite_size, GFP_KERNEL); + if (!total_suite_start) + return total_suite_set; + + /* Append init suites and then all other kunit suites */ + memcpy(total_suite_start, init_suite_set.start, init_num_suites * suite_size); + memcpy(total_suite_start + init_num_suites, suite_set.start, num_suites * suite_size); + + /* Set kunit suite set start and end */ + total_suite_set.start = total_suite_start; + total_suite_set.end = total_suite_start + (init_num_suites + num_suites); + + return total_suite_set; +} + #if IS_BUILTIN(CONFIG_KUNIT) static char *kunit_shutdown; @@ -313,21 +342,41 @@ static void kunit_handle_shutdown(void) int kunit_run_all_tests(void) { - struct kunit_suite_set suite_set = { + struct kunit_suite_set suite_set = {NULL, NULL}; + struct kunit_suite_set filtered_suite_set = {NULL, NULL}; + struct kunit_suite_set init_suite_set = { + __kunit_init_suites_start, __kunit_init_suites_end, + }; + struct kunit_suite_set normal_suite_set = { __kunit_suites_start, __kunit_suites_end, }; + size_t init_num_suites = init_suite_set.end - init_suite_set.start; int err = 0; + + if (init_num_suites > 0) { + suite_set = kunit_merge_suite_sets(init_suite_set, normal_suite_set); + if (!suite_set.start) + goto out; + } else + suite_set = normal_suite_set; + if (!kunit_enabled()) { pr_info("kunit: disabled\n"); - goto out; + goto free_out; } if (filter_glob_param || filter_param) { - suite_set = kunit_filter_suites(&suite_set, filter_glob_param, + filtered_suite_set = kunit_filter_suites(&suite_set, filter_glob_param, filter_param, filter_action_param, &err); + + /* Free original suite set before using filtered suite set */ + if (init_num_suites > 0) + kfree(suite_set.start); + suite_set = filtered_suite_set; + if (err) { pr_err("kunit executor: error filtering suites: %d\n", err); - goto out; + goto free_out; } } @@ -340,9 +389,12 @@ int kunit_run_all_tests(void) else pr_err("kunit executor: unknown action '%s'\n", action_param); - if (filter_glob_param || filter_param) { /* a copy was made of each suite */ +free_out: + if (filter_glob_param || filter_param) kunit_free_suite_set(suite_set); - } + else if (init_num_suites > 0) + /* Don't use kunit_free_suite_set because suites aren't individually allocated */ + kfree(suite_set.start); out: kunit_handle_shutdown(); diff --git a/lib/kunit/test.c b/lib/kunit/test.c index 7deee3701d20..6b60d85ce108 100644 --- a/lib/kunit/test.c +++ b/lib/kunit/test.c @@ -742,28 +742,40 @@ EXPORT_SYMBOL_GPL(__kunit_test_suites_exit); #ifdef CONFIG_MODULES static void kunit_module_init(struct module *mod) { - struct kunit_suite_set suite_set = { + struct kunit_suite_set suite_set, filtered_set; + struct kunit_suite_set normal_suite_set = { mod->kunit_suites, mod->kunit_suites + mod->num_kunit_suites, }; + struct kunit_suite_set init_suite_set = { + mod->kunit_init_suites, mod->kunit_init_suites + mod->num_kunit_init_suites, + }; const char *action = kunit_action(); int err = 0; - suite_set = kunit_filter_suites(&suite_set, + if (mod->num_kunit_init_suites > 0) + suite_set = kunit_merge_suite_sets(init_suite_set, normal_suite_set); + else + suite_set = normal_suite_set; + + filtered_set = kunit_filter_suites(&suite_set, kunit_filter_glob() ?: "*.*", kunit_filter(), kunit_filter_action(), &err); if (err) pr_err("kunit module: error filtering suites: %d\n", err); - mod->kunit_suites = (struct kunit_suite **)suite_set.start; - mod->num_kunit_suites = suite_set.end - suite_set.start; + mod->kunit_suites = (struct kunit_suite **)filtered_set.start; + mod->num_kunit_suites = filtered_set.end - filtered_set.start; + + if (mod->num_kunit_init_suites > 0) + kfree(suite_set.start); if (!action) - kunit_exec_run_tests(&suite_set, false); + kunit_exec_run_tests(&filtered_set, false); else if (!strcmp(action, "list")) - kunit_exec_list_tests(&suite_set, false); + kunit_exec_list_tests(&filtered_set, false); else if (!strcmp(action, "list_attr")) - kunit_exec_list_tests(&suite_set, true); + kunit_exec_list_tests(&filtered_set, true); else pr_err("kunit: unknown action '%s'\n", action); } -- cgit From 6c4ea2f48de9860217ddfedee081d485dbeea7e8 Mon Sep 17 00:00:00 2001 From: Rae Moar Date: Wed, 13 Dec 2023 19:44:19 +0000 Subject: kunit: add is_init test attribute Add is_init test attribute of type bool. Add to_string, get, and filter methods to lib/kunit/attributes.c. Mark each of the tests in the init section with the is_init=true attribute. Add is_init to the attributes documentation. Reviewed-by: David Gow Signed-off-by: Rae Moar Signed-off-by: Shuah Khan --- Documentation/dev-tools/kunit/running_tips.rst | 7 +++ include/kunit/test.h | 1 + lib/kunit/attributes.c | 60 ++++++++++++++++++++++++++ lib/kunit/executor.c | 6 ++- 4 files changed, 73 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/Documentation/dev-tools/kunit/running_tips.rst b/Documentation/dev-tools/kunit/running_tips.rst index 766f9cdea0fa..024e9ad1d1e9 100644 --- a/Documentation/dev-tools/kunit/running_tips.rst +++ b/Documentation/dev-tools/kunit/running_tips.rst @@ -428,3 +428,10 @@ This attribute indicates the name of the module associated with the test. This attribute is automatically saved as a string and is printed for each suite. Tests can also be filtered using this attribute. + +``is_init`` + +This attribute indicates whether the test uses init data or functions. + +This attribute is automatically saved as a boolean and tests can also be +filtered using this attribute. diff --git a/include/kunit/test.h b/include/kunit/test.h index fe79cd736e94..b163b9984b33 100644 --- a/include/kunit/test.h +++ b/include/kunit/test.h @@ -253,6 +253,7 @@ struct kunit_suite { struct dentry *debugfs; struct string_stream *log; int suite_init_err; + bool is_init; }; /* Stores an array of suites, end points one past the end */ diff --git a/lib/kunit/attributes.c b/lib/kunit/attributes.c index 1b512f7e1838..2cf04cc09372 100644 --- a/lib/kunit/attributes.c +++ b/lib/kunit/attributes.c @@ -58,6 +58,16 @@ static const char *attr_enum_to_string(void *attr, const char * const str_list[] return str_list[val]; } +static const char *attr_bool_to_string(void *attr, bool *to_free) +{ + bool val = (bool)attr; + + *to_free = false; + if (val) + return "true"; + return "false"; +} + static const char *attr_speed_to_string(void *attr, bool *to_free) { return attr_enum_to_string(attr, speed_str_list, to_free); @@ -166,6 +176,37 @@ static int attr_string_filter(void *attr, const char *input, int *err) return false; } +static int attr_bool_filter(void *attr, const char *input, int *err) +{ + int i, input_int = -1; + long val = (long)attr; + const char *input_str = NULL; + + for (i = 0; input[i]; i++) { + if (!strchr(op_list, input[i])) { + input_str = input + i; + break; + } + } + + if (!input_str) { + *err = -EINVAL; + pr_err("kunit executor: filter value not found: %s\n", input); + return false; + } + + if (!strcmp(input_str, "true")) + input_int = (int)true; + else if (!strcmp(input_str, "false")) + input_int = (int)false; + else { + *err = -EINVAL; + pr_err("kunit executor: invalid filter input: %s\n", input); + return false; + } + + return int_filter(val, input, input_int, err); +} /* Get Attribute Methods */ @@ -194,6 +235,17 @@ static void *attr_module_get(void *test_or_suite, bool is_test) return (void *) ""; } +static void *attr_is_init_get(void *test_or_suite, bool is_test) +{ + struct kunit_suite *suite = is_test ? NULL : test_or_suite; + struct kunit_case *test = is_test ? test_or_suite : NULL; + + if (test) + return ((void *) NULL); + else + return ((void *) suite->is_init); +} + /* List of all Test Attributes */ static struct kunit_attr kunit_attr_list[] = { @@ -212,6 +264,14 @@ static struct kunit_attr kunit_attr_list[] = { .filter = attr_string_filter, .attr_default = (void *)"", .print = PRINT_SUITE, + }, + { + .name = "is_init", + .get_attr = attr_is_init_get, + .to_string = attr_bool_to_string, + .filter = attr_bool_filter, + .attr_default = (void *)false, + .print = PRINT_SUITE, } }; diff --git a/lib/kunit/executor.c b/lib/kunit/executor.c index 847329c51e91..717b9599036b 100644 --- a/lib/kunit/executor.c +++ b/lib/kunit/executor.c @@ -300,6 +300,7 @@ struct kunit_suite_set kunit_merge_suite_sets(struct kunit_suite_set init_suite_ struct kunit_suite_set total_suite_set = {NULL, NULL}; struct kunit_suite **total_suite_start = NULL; size_t init_num_suites, num_suites, suite_size; + int i = 0; init_num_suites = init_suite_set.end - init_suite_set.start; num_suites = suite_set.end - suite_set.start; @@ -310,8 +311,11 @@ struct kunit_suite_set kunit_merge_suite_sets(struct kunit_suite_set init_suite_ if (!total_suite_start) return total_suite_set; - /* Append init suites and then all other kunit suites */ + /* Append and mark init suites and then append all other kunit suites */ memcpy(total_suite_start, init_suite_set.start, init_num_suites * suite_size); + for (i = 0; i < init_num_suites; i++) + total_suite_start[i]->is_init = true; + memcpy(total_suite_start + init_num_suites, suite_set.start, num_suites * suite_size); /* Set kunit suite set start and end */ -- cgit From d03c720e03bd9bf0b784d80b5d3ede7e2daf3b6e Mon Sep 17 00:00:00 2001 From: "davidgow@google.com" Date: Fri, 15 Dec 2023 15:39:08 +0800 Subject: kunit: Add APIs for managing devices Tests for drivers often require a struct device to pass to other functions. While it's possible to create these with root_device_register(), or to use something like a platform device, this is both a misuse of those APIs, and can be difficult to clean up after, for example, a failed assertion. Add some KUnit-specific functions for registering and unregistering a struct device: - kunit_device_register() - kunit_device_register_with_driver() - kunit_device_unregister() These helpers allocate a on a 'kunit' bus which will either probe the driver passed in (kunit_device_register_with_driver), or will create a stub driver (kunit_device_register) which is cleaned up on test shutdown. Devices are automatically unregistered on test shutdown, but can be manually unregistered earlier with kunit_device_unregister() in order to, for example, test device release code. Reviewed-by: Matti Vaittinen Reviewed-by: Maxime Ripard Signed-off-by: David Gow Reviewed-by: Greg Kroah-Hartman Signed-off-by: Shuah Khan --- Documentation/dev-tools/kunit/api/resource.rst | 9 ++ Documentation/dev-tools/kunit/usage.rst | 50 +++++++ include/kunit/device.h | 80 +++++++++++ lib/kunit/Makefile | 3 +- lib/kunit/device-impl.h | 17 +++ lib/kunit/device.c | 181 +++++++++++++++++++++++++ lib/kunit/kunit-test.c | 134 +++++++++++++++++- lib/kunit/test.c | 3 + 8 files changed, 475 insertions(+), 2 deletions(-) create mode 100644 include/kunit/device.h create mode 100644 lib/kunit/device-impl.h create mode 100644 lib/kunit/device.c (limited to 'include') diff --git a/Documentation/dev-tools/kunit/api/resource.rst b/Documentation/dev-tools/kunit/api/resource.rst index 0a94f831259e..ec6002a6b0db 100644 --- a/Documentation/dev-tools/kunit/api/resource.rst +++ b/Documentation/dev-tools/kunit/api/resource.rst @@ -11,3 +11,12 @@ state on a per-test basis, register custom cleanup actions, and more. .. kernel-doc:: include/kunit/resource.h :internal: + +Managed Devices +--------------- + +Functions for using KUnit-managed struct device and struct device_driver. +Include ``kunit/device.h`` to use these. + +.. kernel-doc:: include/kunit/device.h + :internal: diff --git a/Documentation/dev-tools/kunit/usage.rst b/Documentation/dev-tools/kunit/usage.rst index 9db12e91668e..53c6f7dc8a42 100644 --- a/Documentation/dev-tools/kunit/usage.rst +++ b/Documentation/dev-tools/kunit/usage.rst @@ -797,3 +797,53 @@ structures as shown below: KUnit is not enabled, or if no test is running in the current task, it will do nothing. This compiles down to either a no-op or a static key check, so will have a negligible performance impact when no test is running. + +Managing Fake Devices and Drivers +--------------------------------- + +When testing drivers or code which interacts with drivers, many functions will +require a ``struct device`` or ``struct device_driver``. In many cases, setting +up a real device is not required to test any given function, so a fake device +can be used instead. + +KUnit provides helper functions to create and manage these fake devices, which +are internally of type ``struct kunit_device``, and are attached to a special +``kunit_bus``. These devices support managed device resources (devres), as +described in Documentation/driver-api/driver-model/devres.rst + +To create a KUnit-managed ``struct device_driver``, use ``kunit_driver_create()``, +which will create a driver with the given name, on the ``kunit_bus``. This driver +will automatically be destroyed when the corresponding test finishes, but can also +be manually destroyed with ``driver_unregister()``. + +To create a fake device, use the ``kunit_device_register()``, which will create +and register a device, using a new KUnit-managed driver created with ``kunit_driver_create()``. +To provide a specific, non-KUnit-managed driver, use ``kunit_device_register_with_driver()`` +instead. Like with managed drivers, KUnit-managed fake devices are automatically +cleaned up when the test finishes, but can be manually cleaned up early with +``kunit_device_unregister()``. + +The KUnit devices should be used in preference to ``root_device_register()``, and +instead of ``platform_device_register()`` in cases where the device is not otherwise +a platform device. + +For example: + +.. code-block:: c + + #include + + static void test_my_device(struct kunit *test) + { + struct device *fake_device; + const char *dev_managed_string; + + // Create a fake device. + fake_device = kunit_device_register(test, "my_device"); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, fake_device) + + // Pass it to functions which need a device. + dev_managed_string = devm_kstrdup(fake_device, "Hello, World!"); + + // Everything is cleaned up automatically when the test ends. + } \ No newline at end of file diff --git a/include/kunit/device.h b/include/kunit/device.h new file mode 100644 index 000000000000..2450110ad64e --- /dev/null +++ b/include/kunit/device.h @@ -0,0 +1,80 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * KUnit basic device implementation + * + * Helpers for creating and managing fake devices for KUnit tests. + * + * Copyright (C) 2023, Google LLC. + * Author: David Gow + */ + +#ifndef _KUNIT_DEVICE_H +#define _KUNIT_DEVICE_H + +#if IS_ENABLED(CONFIG_KUNIT) + +#include + +struct device; +struct device_driver; + +/** + * kunit_driver_create() - Create a struct device_driver attached to the kunit_bus + * @test: The test context object. + * @name: The name to give the created driver. + * + * Creates a struct device_driver attached to the kunit_bus, with the name @name. + * This driver will automatically be cleaned up on test exit. + * + * Return: a stub struct device_driver, managed by KUnit, with the name @name. + */ +struct device_driver *kunit_driver_create(struct kunit *test, const char *name); + +/** + * kunit_device_register() - Create a struct device for use in KUnit tests + * @test: The test context object. + * @name: The name to give the created device. + * + * Creates a struct kunit_device (which is a struct device) with the given name, + * and a corresponding driver. The device and driver will be cleaned up on test + * exit, or when kunit_device_unregister is called. See also + * kunit_device_register_with_driver, if you wish to provide your own + * struct device_driver. + * + * Return: a pointer to a struct device which will be cleaned up when the test + * exits, or an error pointer if the device could not be allocated or registered. + */ +struct device *kunit_device_register(struct kunit *test, const char *name); + +/** + * kunit_device_register_with_driver() - Create a struct device for use in KUnit tests + * @test: The test context object. + * @name: The name to give the created device. + * @drv: The struct device_driver to associate with the device. + * + * Creates a struct kunit_device (which is a struct device) with the given + * name, and driver. The device will be cleaned up on test exit, or when + * kunit_device_unregister is called. See also kunit_device_register, if you + * wish KUnit to create and manage a driver for you. + * + * Return: a pointer to a struct device which will be cleaned up when the test + * exits, or an error pointer if the device could not be allocated or registered. + */ +struct device *kunit_device_register_with_driver(struct kunit *test, + const char *name, + const struct device_driver *drv); + +/** + * kunit_device_unregister() - Unregister a KUnit-managed device + * @test: The test context object which created the device + * @dev: The device. + * + * Unregisters and destroys a struct device which was created with + * kunit_device_register or kunit_device_register_with_driver. If KUnit created + * a driver, cleans it up as well. + */ +void kunit_device_unregister(struct kunit *test, struct device *dev); + +#endif + +#endif diff --git a/lib/kunit/Makefile b/lib/kunit/Makefile index 46f75f23dfe4..309659a32a78 100644 --- a/lib/kunit/Makefile +++ b/lib/kunit/Makefile @@ -7,7 +7,8 @@ kunit-objs += test.o \ assert.o \ try-catch.o \ executor.o \ - attributes.o + attributes.o \ + device.o ifeq ($(CONFIG_KUNIT_DEBUGFS),y) kunit-objs += debugfs.o diff --git a/lib/kunit/device-impl.h b/lib/kunit/device-impl.h new file mode 100644 index 000000000000..54bd55836405 --- /dev/null +++ b/lib/kunit/device-impl.h @@ -0,0 +1,17 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * KUnit internal header for device helpers + * + * Header for KUnit-internal driver / bus management. + * + * Copyright (C) 2023, Google LLC. + * Author: David Gow + */ + +#ifndef _KUNIT_DEVICE_IMPL_H +#define _KUNIT_DEVICE_IMPL_H + +// For internal use only -- registers the kunit_bus. +int kunit_bus_init(void); + +#endif //_KUNIT_DEVICE_IMPL_H diff --git a/lib/kunit/device.c b/lib/kunit/device.c new file mode 100644 index 000000000000..1db4305b615a --- /dev/null +++ b/lib/kunit/device.c @@ -0,0 +1,181 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * KUnit-managed device implementation + * + * Implementation of struct kunit_device helpers for fake devices whose + * lifecycle is managed by KUnit. + * + * Copyright (C) 2023, Google LLC. + * Author: David Gow + */ + +#include + +#include +#include +#include + +#include "device-impl.h" + +/* Wrappers for use with kunit_add_action() */ +KUNIT_DEFINE_ACTION_WRAPPER(device_unregister_wrapper, device_unregister, struct device *); +KUNIT_DEFINE_ACTION_WRAPPER(driver_unregister_wrapper, driver_unregister, struct device_driver *); + +/* The root device for the KUnit bus, parent of all kunit_devices. */ +static struct device *kunit_bus_device; + +/* A device owned by a KUnit test. */ +struct kunit_device { + struct device dev; + /* The KUnit test which owns this device. */ + struct kunit *owner; + /* If the driver is managed by KUnit and unique to this device. */ + const struct device_driver *driver; +}; + +#define to_kunit_device(d) container_of_const(d, struct kunit_device, dev) + +static struct bus_type kunit_bus_type = { + .name = "kunit", +}; + +/* Register the 'kunit_bus' used for fake devices. */ +int kunit_bus_init(void) +{ + int error; + + kunit_bus_device = root_device_register("kunit"); + if (!kunit_bus_device) + return -ENOMEM; + + error = bus_register(&kunit_bus_type); + if (error) + bus_unregister(&kunit_bus_type); + return error; +} + +/* Release a 'fake' KUnit device. */ +static void kunit_device_release(struct device *d) +{ + kfree(to_kunit_device(d)); +} + +/** + * Create and register a KUnit-managed struct device_driver on the kunit_bus. + * Returns an error pointer on failure. + */ +struct device_driver *kunit_driver_create(struct kunit *test, const char *name) +{ + struct device_driver *driver; + int err = -ENOMEM; + + driver = kunit_kzalloc(test, sizeof(*driver), GFP_KERNEL); + + if (!driver) + return ERR_PTR(err); + + driver->name = name; + driver->bus = &kunit_bus_type; + driver->owner = THIS_MODULE; + + err = driver_register(driver); + if (err) { + kunit_kfree(test, driver); + return ERR_PTR(err); + } + + kunit_add_action(test, driver_unregister_wrapper, driver); + return driver; +} +EXPORT_SYMBOL_GPL(kunit_driver_create); + +/* Helper which creates a kunit_device, attaches it to the kunit_bus*/ +static struct kunit_device *kunit_device_register_internal(struct kunit *test, + const char *name, + const struct device_driver *drv) +{ + struct kunit_device *kunit_dev; + int err = -ENOMEM; + + kunit_dev = kzalloc(sizeof(*kunit_dev), GFP_KERNEL); + if (!kunit_dev) + return ERR_PTR(err); + + kunit_dev->owner = test; + + err = dev_set_name(&kunit_dev->dev, "%s.%s", test->name, name); + if (err) { + kfree(kunit_dev); + return ERR_PTR(err); + } + + kunit_dev->dev.release = kunit_device_release; + kunit_dev->dev.bus = &kunit_bus_type; + kunit_dev->dev.parent = kunit_bus_device; + + err = device_register(&kunit_dev->dev); + if (err) { + put_device(&kunit_dev->dev); + return ERR_PTR(err); + } + + kunit_add_action(test, device_unregister_wrapper, &kunit_dev->dev); + + return kunit_dev; +} + +/** + * Create and register a new KUnit-managed device, using the user-supplied device_driver. + * On failure, returns an error pointer. + */ +struct device *kunit_device_register_with_driver(struct kunit *test, + const char *name, + const struct device_driver *drv) +{ + struct kunit_device *kunit_dev = kunit_device_register_internal(test, name, drv); + + if (IS_ERR_OR_NULL(kunit_dev)) + return ERR_CAST(kunit_dev); + + return &kunit_dev->dev; +} +EXPORT_SYMBOL_GPL(kunit_device_register_with_driver); + +/** + * Create and register a new KUnit-managed device, including a matching device_driver. + * On failure, returns an error pointer. + */ +struct device *kunit_device_register(struct kunit *test, const char *name) +{ + struct device_driver *drv; + struct kunit_device *dev; + + drv = kunit_driver_create(test, name); + if (IS_ERR(drv)) + return ERR_CAST(drv); + + dev = kunit_device_register_internal(test, name, drv); + if (IS_ERR(dev)) { + kunit_release_action(test, driver_unregister_wrapper, (void *)drv); + return ERR_CAST(dev); + } + + /* Request the driver be freed. */ + dev->driver = drv; + + + return &dev->dev; +} +EXPORT_SYMBOL_GPL(kunit_device_register); + +/* Unregisters a KUnit-managed device early (including the driver, if automatically created). */ +void kunit_device_unregister(struct kunit *test, struct device *dev) +{ + const struct device_driver *driver = to_kunit_device(dev)->driver; + + kunit_release_action(test, device_unregister_wrapper, dev); + if (driver) + kunit_release_action(test, driver_unregister_wrapper, (void *)driver); +} +EXPORT_SYMBOL_GPL(kunit_device_unregister); + diff --git a/lib/kunit/kunit-test.c b/lib/kunit/kunit-test.c index ee6927c60979..c4259d910356 100644 --- a/lib/kunit/kunit-test.c +++ b/lib/kunit/kunit-test.c @@ -5,9 +5,13 @@ * Copyright (C) 2019, Google LLC. * Author: Brendan Higgins */ +#include "linux/gfp_types.h" #include #include +#include +#include + #include "string-stream.h" #include "try-catch-impl.h" @@ -687,6 +691,134 @@ static struct kunit_case kunit_current_test_cases[] = { {} }; +static void test_dev_action(void *priv) +{ + *(void **)priv = (void *)1; +} + +static void kunit_device_test(struct kunit *test) +{ + struct device *test_device; + long action_was_run = 0; + + test_device = kunit_device_register(test, "my_device"); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, test_device); + + // Add an action to verify cleanup. + devm_add_action(test_device, test_dev_action, &action_was_run); + + KUNIT_EXPECT_EQ(test, action_was_run, 0); + + kunit_device_unregister(test, test_device); + + KUNIT_EXPECT_EQ(test, action_was_run, 1); +} + +static void kunit_device_cleanup_test(struct kunit *test) +{ + struct device *test_device; + long action_was_run = 0; + + test_device = kunit_device_register(test, "my_device"); + KUNIT_ASSERT_NOT_NULL(test, test_device); + + /* Add an action to verify cleanup. */ + devm_add_action(test_device, test_dev_action, &action_was_run); + + KUNIT_EXPECT_EQ(test, action_was_run, 0); + + /* Force KUnit to run cleanup early. */ + kunit_cleanup(test); + + KUNIT_EXPECT_EQ(test, action_was_run, 1); +} + +struct driver_test_state { + bool driver_device_probed; + bool driver_device_removed; + long action_was_run; +}; + +static int driver_probe_hook(struct device *dev) +{ + struct kunit *test = kunit_get_current_test(); + struct driver_test_state *state = (struct driver_test_state *)test->priv; + + state->driver_device_probed = true; + return 0; +} + +static int driver_remove_hook(struct device *dev) +{ + struct kunit *test = kunit_get_current_test(); + struct driver_test_state *state = (struct driver_test_state *)test->priv; + + state->driver_device_removed = true; + return 0; +} + +static void kunit_device_driver_test(struct kunit *test) +{ + struct device_driver *test_driver; + struct device *test_device; + struct driver_test_state *test_state = kunit_kzalloc(test, sizeof(*test_state), GFP_KERNEL); + + test->priv = test_state; + test_driver = kunit_driver_create(test, "my_driver"); + + // This can fail with an error pointer. + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, test_driver); + + test_driver->probe = driver_probe_hook; + test_driver->remove = driver_remove_hook; + + test_device = kunit_device_register_with_driver(test, "my_device", test_driver); + + // This can fail with an error pointer. + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, test_device); + + // Make sure the probe function was called. + KUNIT_ASSERT_TRUE(test, test_state->driver_device_probed); + + // Add an action to verify cleanup. + devm_add_action(test_device, test_dev_action, &test_state->action_was_run); + + KUNIT_EXPECT_EQ(test, test_state->action_was_run, 0); + + kunit_device_unregister(test, test_device); + test_device = NULL; + + // Make sure the remove hook was called. + KUNIT_ASSERT_TRUE(test, test_state->driver_device_removed); + + // We're going to test this again. + test_state->driver_device_probed = false; + + // The driver should not automatically be destroyed by + // kunit_device_unregister, so we can re-use it. + test_device = kunit_device_register_with_driver(test, "my_device", test_driver); + + // This can fail with an error pointer. + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, test_device); + + // Probe was called again. + KUNIT_ASSERT_TRUE(test, test_state->driver_device_probed); + + // Everything is automatically freed here. +} + +static struct kunit_case kunit_device_test_cases[] = { + KUNIT_CASE(kunit_device_test), + KUNIT_CASE(kunit_device_cleanup_test), + KUNIT_CASE(kunit_device_driver_test), + {} +}; + +static struct kunit_suite kunit_device_test_suite = { + .name = "kunit_device", + .test_cases = kunit_device_test_cases, +}; + static struct kunit_suite kunit_current_test_suite = { .name = "kunit_current", .test_cases = kunit_current_test_cases, @@ -694,6 +826,6 @@ static struct kunit_suite kunit_current_test_suite = { kunit_test_suites(&kunit_try_catch_test_suite, &kunit_resource_test_suite, &kunit_log_test_suite, &kunit_status_test_suite, - &kunit_current_test_suite); + &kunit_current_test_suite, &kunit_device_test_suite); MODULE_LICENSE("GPL v2"); diff --git a/lib/kunit/test.c b/lib/kunit/test.c index 088489856db8..14a77b2d702a 100644 --- a/lib/kunit/test.c +++ b/lib/kunit/test.c @@ -19,6 +19,7 @@ #include #include "debugfs.h" +#include "device-impl.h" #include "hooks-impl.h" #include "string-stream.h" #include "try-catch-impl.h" @@ -900,6 +901,8 @@ static int __init kunit_init(void) kunit_install_hooks(); kunit_debugfs_init(); + + kunit_bus_init(); #ifdef CONFIG_MODULES return register_module_notifier(&kunit_mod_nb); #else -- cgit From fcbac39b7d5e776bed058281af5d3248b94f1282 Mon Sep 17 00:00:00 2001 From: Richard Fitzgerald Date: Thu, 21 Dec 2023 10:38:56 +0000 Subject: kunit: Allow passing function pointer to kunit_activate_static_stub() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Swap the arguments to typecheck_fn() in kunit_activate_static_stub() so that real_fn_addr can be either the function itself or a pointer to that function. This is useful to simplify redirecting static functions in a module. Having to pass the actual function meant that it must be exported from the module. Either making the 'static' and EXPORT_SYMBOL*() conditional (which makes the code messy), or change it to always exported (which increases the export namespace and prevents the compiler inlining a trivial stub function in non-test builds). With the original definition of kunit_activate_static_stub() the address of real_fn_addr was passed to typecheck_fn() as the type to be passed. This meant that if real_fn_addr was a pointer-to-function it would resolve to a ** instead of a *, giving an error like this: error: initialization of ‘int (**)(int)’ from incompatible pointer type ‘int (*)(int)’ [-Werror=incompatible-pointer-types] kunit_activate_static_stub(test, add_one_fn_ptr, subtract_one); | ^~~~~~~~~~~~ ./include/linux/typecheck.h:21:25: note: in definition of macro ‘typecheck_fn’ 21 | ({ typeof(type) __tmp = function; \ Swapping the arguments to typecheck_fn makes it take the type of a pointer to the replacement function. Either a function or a pointer to function can be assigned to that. For example: static int some_function(int x) { /* whatever */ } int (* some_function_ptr)(int) = some_function; static int replacement(int x) { /* whatever */ } Then: kunit_activate_static_stub(test, some_function, replacement); yields: typecheck_fn(typeof(&replacement), some_function); and: kunit_activate_static_stub(test, some_function_ptr, replacement); yields: typecheck_fn(typeof(&replacement), some_function_ptr); The two typecheck_fn() then resolve to: int (*__tmp)(int) = some_function; and int (*__tmp)(int) = some_function_ptr; Both of these are valid. In the first case the compiler inserts an implicit '&' to take the address of the supplied function, and in the second case the RHS is already a pointer to the same type. Signed-off-by: Richard Fitzgerald Reviewed-by: Rae Moar Reviewed-by: David Gow Signed-off-by: Shuah Khan --- include/kunit/static_stub.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include') diff --git a/include/kunit/static_stub.h b/include/kunit/static_stub.h index 85315c80b303..bf940322dfc0 100644 --- a/include/kunit/static_stub.h +++ b/include/kunit/static_stub.h @@ -93,7 +93,7 @@ void __kunit_activate_static_stub(struct kunit *test, * The redirection can be disabled again with kunit_deactivate_static_stub(). */ #define kunit_activate_static_stub(test, real_fn_addr, replacement_addr) do { \ - typecheck_fn(typeof(&real_fn_addr), replacement_addr); \ + typecheck_fn(typeof(&replacement_addr), real_fn_addr); \ __kunit_activate_static_stub(test, real_fn_addr, replacement_addr); \ } while (0) -- cgit From 7ece381aa72d430ee117958abb5bb23e21d72f1d Mon Sep 17 00:00:00 2001 From: Richard Fitzgerald Date: Wed, 20 Dec 2023 15:52:56 +0000 Subject: kunit: Protect string comparisons against NULL Add NULL checks to KUNIT_BINARY_STR_ASSERTION() so that it will fail cleanly if either pointer is NULL, instead of causing a NULL pointer dereference in the strcmp(). A test failure could be that a string is unexpectedly NULL. This could be trapped by KUNIT_ASSERT_NOT_NULL() but that would terminate the test at that point. It's preferable that the KUNIT_EXPECT_STR*() macros can handle NULL pointers as a failure. Signed-off-by: Richard Fitzgerald Reviewed-by: David Gow Reviewed-by: Muhammad Usama Anjum Signed-off-by: Shuah Khan --- include/kunit/test.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'include') diff --git a/include/kunit/test.h b/include/kunit/test.h index b163b9984b33..c2ce379c329b 100644 --- a/include/kunit/test.h +++ b/include/kunit/test.h @@ -758,7 +758,7 @@ do { \ .right_text = #right, \ }; \ \ - if (likely(strcmp(__left, __right) op 0)) \ + if (likely((__left) && (__right) && (strcmp(__left, __right) op 0))) \ break; \ \ \ -- cgit