2 * kmod stress test driver
4 * Copyright (C) 2017 Luis R. Rodriguez <mcgrof@kernel.org>
6 * This program is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License as published by the Free
8 * Software Foundation; either version 2 of the License, or at your option any
9 * later version; or, when distributed separately from the Linux kernel or
10 * when incorporated into other software packages, subject to the following
13 * This program is free software; you can redistribute it and/or modify it
14 * under the terms of copyleft-next (version 0.3.1 or later) as published
15 * at http://copyleft-next.org/.
17 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
20 * This driver provides an interface to trigger and test the kernel's
21 * module loader through a series of configurations and a few triggers.
22 * To test this driver use the following script as root:
24 * tools/testing/selftests/kmod/kmod.sh --help
27 #include <linux/kernel.h>
28 #include <linux/module.h>
29 #include <linux/kmod.h>
30 #include <linux/printk.h>
31 #include <linux/kthread.h>
32 #include <linux/sched.h>
34 #include <linux/miscdevice.h>
35 #include <linux/vmalloc.h>
36 #include <linux/slab.h>
37 #include <linux/device.h>
39 #define TEST_START_NUM_THREADS 50
40 #define TEST_START_DRIVER "test_module"
41 #define TEST_START_TEST_FS "xfs"
42 #define TEST_START_TEST_CASE TEST_KMOD_DRIVER
45 static bool force_init_test = false;
46 module_param(force_init_test, bool_enable_only, 0644);
47 MODULE_PARM_DESC(force_init_test,
48 "Force kicking a test immediately after driver loads");
51 * For device allocation / registration
53 static DEFINE_MUTEX(reg_dev_mutex);
54 static LIST_HEAD(reg_test_devs);
57 * num_test_devs actually represents the *next* ID of the next
58 * device we will allow to create.
60 static int num_test_devs;
63 * enum kmod_test_case - linker table test case
65 * If you add a test case, please be sure to review if you need to se
66 * @need_mod_put for your tests case.
68 * @TEST_KMOD_DRIVER: stress tests request_module()
69 * @TEST_KMOD_FS_TYPE: stress tests get_fs_type()
72 __TEST_KMOD_INVALID = 0,
83 unsigned int num_threads;
84 enum kmod_test_case test_case;
88 struct kmod_test_device;
91 * kmod_test_device_info - thread info
93 * @ret_sync: return value if request_module() is used, sync request for
95 * @fs_sync: return value of get_fs_type() for @TEST_KMOD_FS_TYPE
96 * @thread_idx: thread ID
97 * @test_dev: test device test is being performed under
98 * @need_mod_put: Some tests (get_fs_type() is one) requires putting the module
99 * (module_put(fs_sync->owner)) when done, otherwise you will not be able
100 * to unload the respective modules and re-test. We use this to keep
101 * accounting of when we need this and to help out in case we need to
102 * error out and deal with module_put() on error.
104 struct kmod_test_device_info {
106 struct file_system_type *fs_sync;
107 struct task_struct *task_sync;
108 unsigned int thread_idx;
109 struct kmod_test_device *test_dev;
114 * kmod_test_device - test device to help test kmod
116 * @dev_idx: unique ID for test device
117 * @config: configuration for the test
118 * @misc_dev: we use a misc device under the hood
119 * @dev: pointer to misc_dev's own struct device
120 * @config_mutex: protects configuration of test
121 * @trigger_mutex: the test trigger can only be fired once at a time
122 * @thread_lock: protects @done count, and the @info per each thread
123 * @done: number of threads which have completed or failed
124 * @test_is_oom: when we run out of memory, use this to halt moving forward
125 * @kthreads_done: completion used to signal when all work is done
126 * @list: needed to be part of the reg_test_devs
127 * @info: array of info for each thread
129 struct kmod_test_device {
131 struct test_config config;
132 struct miscdevice misc_dev;
134 struct mutex config_mutex;
135 struct mutex trigger_mutex;
136 struct mutex thread_mutex;
141 struct completion kthreads_done;
142 struct list_head list;
144 struct kmod_test_device_info *info;
147 static const char *test_case_str(enum kmod_test_case test_case)
150 case TEST_KMOD_DRIVER:
151 return "TEST_KMOD_DRIVER";
152 case TEST_KMOD_FS_TYPE:
153 return "TEST_KMOD_FS_TYPE";
159 static struct miscdevice *dev_to_misc_dev(struct device *dev)
161 return dev_get_drvdata(dev);
164 static struct kmod_test_device *misc_dev_to_test_dev(struct miscdevice *misc_dev)
166 return container_of(misc_dev, struct kmod_test_device, misc_dev);
169 static struct kmod_test_device *dev_to_test_dev(struct device *dev)
171 struct miscdevice *misc_dev;
173 misc_dev = dev_to_misc_dev(dev);
175 return misc_dev_to_test_dev(misc_dev);
178 /* Must run with thread_mutex held */
179 static void kmod_test_done_check(struct kmod_test_device *test_dev,
182 struct test_config *config = &test_dev->config;
185 dev_dbg(test_dev->dev, "Done thread count: %u\n", test_dev->done);
187 if (test_dev->done == config->num_threads) {
188 dev_info(test_dev->dev, "Done: %u threads have all run now\n",
190 dev_info(test_dev->dev, "Last thread to run: %u\n", idx);
191 complete(&test_dev->kthreads_done);
195 static void test_kmod_put_module(struct kmod_test_device_info *info)
197 struct kmod_test_device *test_dev = info->test_dev;
198 struct test_config *config = &test_dev->config;
200 if (!info->need_mod_put)
203 switch (config->test_case) {
204 case TEST_KMOD_DRIVER:
206 case TEST_KMOD_FS_TYPE:
207 if (info->fs_sync && info->fs_sync->owner)
208 module_put(info->fs_sync->owner);
214 info->need_mod_put = true;
217 static int run_request(void *data)
219 struct kmod_test_device_info *info = data;
220 struct kmod_test_device *test_dev = info->test_dev;
221 struct test_config *config = &test_dev->config;
223 switch (config->test_case) {
224 case TEST_KMOD_DRIVER:
225 info->ret_sync = request_module("%s", config->test_driver);
227 case TEST_KMOD_FS_TYPE:
228 info->fs_sync = get_fs_type(config->test_fs);
229 info->need_mod_put = true;
232 /* __trigger_config_run() already checked for test sanity */
237 dev_dbg(test_dev->dev, "Ran thread %u\n", info->thread_idx);
239 test_kmod_put_module(info);
241 mutex_lock(&test_dev->thread_mutex);
242 info->task_sync = NULL;
243 kmod_test_done_check(test_dev, info->thread_idx);
244 mutex_unlock(&test_dev->thread_mutex);
249 static int tally_work_test(struct kmod_test_device_info *info)
251 struct kmod_test_device *test_dev = info->test_dev;
252 struct test_config *config = &test_dev->config;
255 switch (config->test_case) {
256 case TEST_KMOD_DRIVER:
258 * Only capture errors, if one is found that's
261 if (info->ret_sync != 0)
262 err_ret = info->ret_sync;
263 dev_info(test_dev->dev,
264 "Sync thread %d return status: %d\n",
265 info->thread_idx, info->ret_sync);
267 case TEST_KMOD_FS_TYPE:
268 /* For now we make this simple */
271 dev_info(test_dev->dev, "Sync thread %u fs: %s\n",
272 info->thread_idx, info->fs_sync ? config->test_fs :
283 * XXX: add result option to display if all errors did not match.
284 * For now we just keep any error code if one was found.
286 * If this ran it means *all* tasks were created fine and we
287 * are now just collecting results.
289 * Only propagate errors, do not override with a subsequent sucess case.
291 static void tally_up_work(struct kmod_test_device *test_dev)
293 struct test_config *config = &test_dev->config;
294 struct kmod_test_device_info *info;
299 mutex_lock(&test_dev->thread_mutex);
301 dev_info(test_dev->dev, "Results:\n");
303 for (idx=0; idx < config->num_threads; idx++) {
304 info = &test_dev->info[idx];
305 ret = tally_work_test(info);
311 * Note: request_module() returns 256 for a module not found even
312 * though modprobe itself returns 1.
314 config->test_result = err_ret;
316 mutex_unlock(&test_dev->thread_mutex);
319 static int try_one_request(struct kmod_test_device *test_dev, unsigned int idx)
321 struct kmod_test_device_info *info = &test_dev->info[idx];
322 int fail_ret = -ENOMEM;
324 mutex_lock(&test_dev->thread_mutex);
326 info->thread_idx = idx;
327 info->test_dev = test_dev;
328 info->task_sync = kthread_run(run_request, info, "%s-%u",
329 KBUILD_MODNAME, idx);
331 if (!info->task_sync || IS_ERR(info->task_sync)) {
332 test_dev->test_is_oom = true;
333 dev_err(test_dev->dev, "Setting up thread %u failed\n", idx);
334 info->task_sync = NULL;
337 dev_dbg(test_dev->dev, "Kicked off thread %u\n", idx);
339 mutex_unlock(&test_dev->thread_mutex);
344 info->ret_sync = fail_ret;
345 mutex_unlock(&test_dev->thread_mutex);
350 static void test_dev_kmod_stop_tests(struct kmod_test_device *test_dev)
352 struct test_config *config = &test_dev->config;
353 struct kmod_test_device_info *info;
356 dev_info(test_dev->dev, "Ending request_module() tests\n");
358 mutex_lock(&test_dev->thread_mutex);
360 for (i=0; i < config->num_threads; i++) {
361 info = &test_dev->info[i];
362 if (info->task_sync && !IS_ERR(info->task_sync)) {
363 dev_info(test_dev->dev,
364 "Stopping still-running thread %i\n", i);
365 kthread_stop(info->task_sync);
369 * info->task_sync is well protected, it can only be
370 * NULL or a pointer to a struct. If its NULL we either
371 * never ran, or we did and we completed the work. Completed
372 * tasks *always* put the module for us. This is a sanity
373 * check -- just in case.
375 if (info->task_sync && info->need_mod_put)
376 test_kmod_put_module(info);
379 mutex_unlock(&test_dev->thread_mutex);
383 * Only wait *iff* we did not run into any errors during all of our thread
384 * set up. If run into any issues we stop threads and just bail out with
385 * an error to the trigger. This also means we don't need any tally work
386 * for any threads which fail.
388 static int try_requests(struct kmod_test_device *test_dev)
390 struct test_config *config = &test_dev->config;
393 bool any_error = false;
395 for (idx=0; idx < config->num_threads; idx++) {
396 if (test_dev->test_is_oom) {
401 ret = try_one_request(test_dev, idx);
409 test_dev->test_is_oom = false;
410 dev_info(test_dev->dev,
411 "No errors were found while initializing threads\n");
412 wait_for_completion(&test_dev->kthreads_done);
413 tally_up_work(test_dev);
415 test_dev->test_is_oom = true;
416 dev_info(test_dev->dev,
417 "At least one thread failed to start, stop all work\n");
418 test_dev_kmod_stop_tests(test_dev);
425 static int run_test_driver(struct kmod_test_device *test_dev)
427 struct test_config *config = &test_dev->config;
429 dev_info(test_dev->dev, "Test case: %s (%u)\n",
430 test_case_str(config->test_case),
432 dev_info(test_dev->dev, "Test driver to load: %s\n",
433 config->test_driver);
434 dev_info(test_dev->dev, "Number of threads to run: %u\n",
435 config->num_threads);
436 dev_info(test_dev->dev, "Thread IDs will range from 0 - %u\n",
437 config->num_threads - 1);
439 return try_requests(test_dev);
442 static int run_test_fs_type(struct kmod_test_device *test_dev)
444 struct test_config *config = &test_dev->config;
446 dev_info(test_dev->dev, "Test case: %s (%u)\n",
447 test_case_str(config->test_case),
449 dev_info(test_dev->dev, "Test filesystem to load: %s\n",
451 dev_info(test_dev->dev, "Number of threads to run: %u\n",
452 config->num_threads);
453 dev_info(test_dev->dev, "Thread IDs will range from 0 - %u\n",
454 config->num_threads - 1);
456 return try_requests(test_dev);
459 static ssize_t config_show(struct device *dev,
460 struct device_attribute *attr,
463 struct kmod_test_device *test_dev = dev_to_test_dev(dev);
464 struct test_config *config = &test_dev->config;
467 mutex_lock(&test_dev->config_mutex);
469 len += snprintf(buf, PAGE_SIZE,
470 "Custom trigger configuration for: %s\n",
473 len += snprintf(buf+len, PAGE_SIZE - len,
474 "Number of threads:\t%u\n",
475 config->num_threads);
477 len += snprintf(buf+len, PAGE_SIZE - len,
478 "Test_case:\t%s (%u)\n",
479 test_case_str(config->test_case),
482 if (config->test_driver)
483 len += snprintf(buf+len, PAGE_SIZE - len,
485 config->test_driver);
487 len += snprintf(buf+len, PAGE_SIZE - len,
491 len += snprintf(buf+len, PAGE_SIZE - len,
495 len += snprintf(buf+len, PAGE_SIZE - len,
498 mutex_unlock(&test_dev->config_mutex);
502 static DEVICE_ATTR_RO(config);
505 * This ensures we don't allow kicking threads through if our configuration
508 static int __trigger_config_run(struct kmod_test_device *test_dev)
510 struct test_config *config = &test_dev->config;
514 switch (config->test_case) {
515 case TEST_KMOD_DRIVER:
516 return run_test_driver(test_dev);
517 case TEST_KMOD_FS_TYPE:
518 return run_test_fs_type(test_dev);
520 dev_warn(test_dev->dev,
521 "Invalid test case requested: %u\n",
527 static int trigger_config_run(struct kmod_test_device *test_dev)
529 struct test_config *config = &test_dev->config;
532 mutex_lock(&test_dev->trigger_mutex);
533 mutex_lock(&test_dev->config_mutex);
535 ret = __trigger_config_run(test_dev);
538 dev_info(test_dev->dev, "General test result: %d\n",
539 config->test_result);
542 * We must return 0 after a trigger even unless something went
543 * wrong with the setup of the test. If the test setup went fine
544 * then userspace must just check the result of config->test_result.
545 * One issue with relying on the return from a call in the kernel
546 * is if the kernel returns a possitive value using this trigger
547 * will not return the value to userspace, it would be lost.
549 * By not relying on capturing the return value of tests we are using
550 * through the trigger it also us to run tests with set -e and only
551 * fail when something went wrong with the driver upon trigger
557 mutex_unlock(&test_dev->config_mutex);
558 mutex_unlock(&test_dev->trigger_mutex);
564 trigger_config_store(struct device *dev,
565 struct device_attribute *attr,
566 const char *buf, size_t count)
568 struct kmod_test_device *test_dev = dev_to_test_dev(dev);
571 if (test_dev->test_is_oom)
574 /* For all intents and purposes we don't care what userspace
575 * sent this trigger, we care only that we were triggered.
576 * We treat the return value only for caputuring issues with
577 * the test setup. At this point all the test variables should
578 * have been allocated so typically this should never fail.
580 ret = trigger_config_run(test_dev);
581 if (unlikely(ret < 0))
585 * Note: any return > 0 will be treated as success
586 * and the error value will not be available to userspace.
587 * Do not rely on trying to send to userspace a test value
588 * return value as possitive return errors will be lost.
590 if (WARN_ON(ret > 0))
597 static DEVICE_ATTR_WO(trigger_config);
600 * XXX: move to kstrncpy() once merged.
602 * Users should use kfree_const() when freeing these.
604 static int __kstrncpy(char **dst, const char *name, size_t count, gfp_t gfp)
606 *dst = kstrndup(name, count, gfp);
612 static int config_copy_test_driver_name(struct test_config *config,
616 return __kstrncpy(&config->test_driver, name, count, GFP_KERNEL);
620 static int config_copy_test_fs(struct test_config *config, const char *name,
623 return __kstrncpy(&config->test_fs, name, count, GFP_KERNEL);
626 static void __kmod_config_free(struct test_config *config)
631 kfree_const(config->test_driver);
632 config->test_driver = NULL;
634 kfree_const(config->test_fs);
635 config->test_fs = NULL;
638 static void kmod_config_free(struct kmod_test_device *test_dev)
640 struct test_config *config;
645 config = &test_dev->config;
647 mutex_lock(&test_dev->config_mutex);
648 __kmod_config_free(config);
649 mutex_unlock(&test_dev->config_mutex);
652 static ssize_t config_test_driver_store(struct device *dev,
653 struct device_attribute *attr,
654 const char *buf, size_t count)
656 struct kmod_test_device *test_dev = dev_to_test_dev(dev);
657 struct test_config *config = &test_dev->config;
660 mutex_lock(&test_dev->config_mutex);
662 kfree_const(config->test_driver);
663 config->test_driver = NULL;
665 copied = config_copy_test_driver_name(config, buf, count);
666 mutex_unlock(&test_dev->config_mutex);
672 * As per sysfs_kf_seq_show() the buf is max PAGE_SIZE.
674 static ssize_t config_test_show_str(struct mutex *config_mutex,
680 mutex_lock(config_mutex);
681 len = snprintf(dst, PAGE_SIZE, "%s\n", src);
682 mutex_unlock(config_mutex);
687 static ssize_t config_test_driver_show(struct device *dev,
688 struct device_attribute *attr,
691 struct kmod_test_device *test_dev = dev_to_test_dev(dev);
692 struct test_config *config = &test_dev->config;
694 return config_test_show_str(&test_dev->config_mutex, buf,
695 config->test_driver);
697 static DEVICE_ATTR_RW(config_test_driver);
699 static ssize_t config_test_fs_store(struct device *dev,
700 struct device_attribute *attr,
701 const char *buf, size_t count)
703 struct kmod_test_device *test_dev = dev_to_test_dev(dev);
704 struct test_config *config = &test_dev->config;
707 mutex_lock(&test_dev->config_mutex);
709 kfree_const(config->test_fs);
710 config->test_fs = NULL;
712 copied = config_copy_test_fs(config, buf, count);
713 mutex_unlock(&test_dev->config_mutex);
718 static ssize_t config_test_fs_show(struct device *dev,
719 struct device_attribute *attr,
722 struct kmod_test_device *test_dev = dev_to_test_dev(dev);
723 struct test_config *config = &test_dev->config;
725 return config_test_show_str(&test_dev->config_mutex, buf,
728 static DEVICE_ATTR_RW(config_test_fs);
730 static int trigger_config_run_type(struct kmod_test_device *test_dev,
731 enum kmod_test_case test_case,
732 const char *test_str)
735 struct test_config *config = &test_dev->config;
737 mutex_lock(&test_dev->config_mutex);
740 case TEST_KMOD_DRIVER:
741 kfree_const(config->test_driver);
742 config->test_driver = NULL;
743 copied = config_copy_test_driver_name(config, test_str,
746 case TEST_KMOD_FS_TYPE:
747 kfree_const(config->test_fs);
748 config->test_fs = NULL;
749 copied = config_copy_test_fs(config, test_str,
753 mutex_unlock(&test_dev->config_mutex);
757 config->test_case = test_case;
759 mutex_unlock(&test_dev->config_mutex);
761 if (copied <= 0 || copied != strlen(test_str)) {
762 test_dev->test_is_oom = true;
766 test_dev->test_is_oom = false;
768 return trigger_config_run(test_dev);
771 static void free_test_dev_info(struct kmod_test_device *test_dev)
773 vfree(test_dev->info);
774 test_dev->info = NULL;
777 static int kmod_config_sync_info(struct kmod_test_device *test_dev)
779 struct test_config *config = &test_dev->config;
781 free_test_dev_info(test_dev);
783 vzalloc(array_size(sizeof(struct kmod_test_device_info),
784 config->num_threads));
792 * Old kernels may not have this, if you want to port this code to
793 * test it on older kernels.
795 #ifdef get_kmod_umh_limit
796 static unsigned int kmod_init_test_thread_limit(void)
798 return get_kmod_umh_limit();
801 static unsigned int kmod_init_test_thread_limit(void)
803 return TEST_START_NUM_THREADS;
807 static int __kmod_config_init(struct kmod_test_device *test_dev)
809 struct test_config *config = &test_dev->config;
810 int ret = -ENOMEM, copied;
812 __kmod_config_free(config);
814 copied = config_copy_test_driver_name(config, TEST_START_DRIVER,
815 strlen(TEST_START_DRIVER));
816 if (copied != strlen(TEST_START_DRIVER))
819 copied = config_copy_test_fs(config, TEST_START_TEST_FS,
820 strlen(TEST_START_TEST_FS));
821 if (copied != strlen(TEST_START_TEST_FS))
824 config->num_threads = kmod_init_test_thread_limit();
825 config->test_result = 0;
826 config->test_case = TEST_START_TEST_CASE;
828 ret = kmod_config_sync_info(test_dev);
832 test_dev->test_is_oom = false;
837 test_dev->test_is_oom = true;
838 WARN_ON(test_dev->test_is_oom);
840 __kmod_config_free(config);
845 static ssize_t reset_store(struct device *dev,
846 struct device_attribute *attr,
847 const char *buf, size_t count)
849 struct kmod_test_device *test_dev = dev_to_test_dev(dev);
852 mutex_lock(&test_dev->trigger_mutex);
853 mutex_lock(&test_dev->config_mutex);
855 ret = __kmod_config_init(test_dev);
858 dev_err(dev, "could not alloc settings for config trigger: %d\n",
863 dev_info(dev, "reset\n");
867 mutex_unlock(&test_dev->config_mutex);
868 mutex_unlock(&test_dev->trigger_mutex);
872 static DEVICE_ATTR_WO(reset);
874 static int test_dev_config_update_uint_sync(struct kmod_test_device *test_dev,
875 const char *buf, size_t size,
876 unsigned int *config,
877 int (*test_sync)(struct kmod_test_device *test_dev))
881 unsigned int old_val;
883 ret = kstrtoul(buf, 10, &new);
890 mutex_lock(&test_dev->config_mutex);
893 *(unsigned int *)config = new;
895 ret = test_sync(test_dev);
897 *(unsigned int *)config = old_val;
899 ret = test_sync(test_dev);
902 mutex_unlock(&test_dev->config_mutex);
906 mutex_unlock(&test_dev->config_mutex);
907 /* Always return full write size even if we didn't consume all */
911 static int test_dev_config_update_uint_range(struct kmod_test_device *test_dev,
912 const char *buf, size_t size,
913 unsigned int *config,
920 ret = kstrtoul(buf, 10, &new);
924 if (new < min || new > max)
927 mutex_lock(&test_dev->config_mutex);
929 mutex_unlock(&test_dev->config_mutex);
931 /* Always return full write size even if we didn't consume all */
935 static int test_dev_config_update_int(struct kmod_test_device *test_dev,
936 const char *buf, size_t size,
942 ret = kstrtol(buf, 10, &new);
946 if (new < INT_MIN || new > INT_MAX)
949 mutex_lock(&test_dev->config_mutex);
951 mutex_unlock(&test_dev->config_mutex);
952 /* Always return full write size even if we didn't consume all */
956 static ssize_t test_dev_config_show_int(struct kmod_test_device *test_dev,
962 mutex_lock(&test_dev->config_mutex);
964 mutex_unlock(&test_dev->config_mutex);
966 return snprintf(buf, PAGE_SIZE, "%d\n", val);
969 static ssize_t test_dev_config_show_uint(struct kmod_test_device *test_dev,
975 mutex_lock(&test_dev->config_mutex);
977 mutex_unlock(&test_dev->config_mutex);
979 return snprintf(buf, PAGE_SIZE, "%u\n", val);
982 static ssize_t test_result_store(struct device *dev,
983 struct device_attribute *attr,
984 const char *buf, size_t count)
986 struct kmod_test_device *test_dev = dev_to_test_dev(dev);
987 struct test_config *config = &test_dev->config;
989 return test_dev_config_update_int(test_dev, buf, count,
990 &config->test_result);
993 static ssize_t config_num_threads_store(struct device *dev,
994 struct device_attribute *attr,
995 const char *buf, size_t count)
997 struct kmod_test_device *test_dev = dev_to_test_dev(dev);
998 struct test_config *config = &test_dev->config;
1000 return test_dev_config_update_uint_sync(test_dev, buf, count,
1001 &config->num_threads,
1002 kmod_config_sync_info);
1005 static ssize_t config_num_threads_show(struct device *dev,
1006 struct device_attribute *attr,
1009 struct kmod_test_device *test_dev = dev_to_test_dev(dev);
1010 struct test_config *config = &test_dev->config;
1012 return test_dev_config_show_int(test_dev, buf, config->num_threads);
1014 static DEVICE_ATTR_RW(config_num_threads);
1016 static ssize_t config_test_case_store(struct device *dev,
1017 struct device_attribute *attr,
1018 const char *buf, size_t count)
1020 struct kmod_test_device *test_dev = dev_to_test_dev(dev);
1021 struct test_config *config = &test_dev->config;
1023 return test_dev_config_update_uint_range(test_dev, buf, count,
1025 __TEST_KMOD_INVALID + 1,
1026 __TEST_KMOD_MAX - 1);
1029 static ssize_t config_test_case_show(struct device *dev,
1030 struct device_attribute *attr,
1033 struct kmod_test_device *test_dev = dev_to_test_dev(dev);
1034 struct test_config *config = &test_dev->config;
1036 return test_dev_config_show_uint(test_dev, buf, config->test_case);
1038 static DEVICE_ATTR_RW(config_test_case);
1040 static ssize_t test_result_show(struct device *dev,
1041 struct device_attribute *attr,
1044 struct kmod_test_device *test_dev = dev_to_test_dev(dev);
1045 struct test_config *config = &test_dev->config;
1047 return test_dev_config_show_int(test_dev, buf, config->test_result);
1049 static DEVICE_ATTR_RW(test_result);
1051 #define TEST_KMOD_DEV_ATTR(name) &dev_attr_##name.attr
1053 static struct attribute *test_dev_attrs[] = {
1054 TEST_KMOD_DEV_ATTR(trigger_config),
1055 TEST_KMOD_DEV_ATTR(config),
1056 TEST_KMOD_DEV_ATTR(reset),
1058 TEST_KMOD_DEV_ATTR(config_test_driver),
1059 TEST_KMOD_DEV_ATTR(config_test_fs),
1060 TEST_KMOD_DEV_ATTR(config_num_threads),
1061 TEST_KMOD_DEV_ATTR(config_test_case),
1062 TEST_KMOD_DEV_ATTR(test_result),
1067 ATTRIBUTE_GROUPS(test_dev);
1069 static int kmod_config_init(struct kmod_test_device *test_dev)
1073 mutex_lock(&test_dev->config_mutex);
1074 ret = __kmod_config_init(test_dev);
1075 mutex_unlock(&test_dev->config_mutex);
1080 static struct kmod_test_device *alloc_test_dev_kmod(int idx)
1083 struct kmod_test_device *test_dev;
1084 struct miscdevice *misc_dev;
1086 test_dev = vzalloc(sizeof(struct kmod_test_device));
1090 mutex_init(&test_dev->config_mutex);
1091 mutex_init(&test_dev->trigger_mutex);
1092 mutex_init(&test_dev->thread_mutex);
1094 init_completion(&test_dev->kthreads_done);
1096 ret = kmod_config_init(test_dev);
1098 pr_err("Cannot alloc kmod_config_init()\n");
1102 test_dev->dev_idx = idx;
1103 misc_dev = &test_dev->misc_dev;
1105 misc_dev->minor = MISC_DYNAMIC_MINOR;
1106 misc_dev->name = kasprintf(GFP_KERNEL, "test_kmod%d", idx);
1107 if (!misc_dev->name) {
1108 pr_err("Cannot alloc misc_dev->name\n");
1109 goto err_out_free_config;
1111 misc_dev->groups = test_dev_groups;
1115 err_out_free_config:
1116 free_test_dev_info(test_dev);
1117 kmod_config_free(test_dev);
1125 static void free_test_dev_kmod(struct kmod_test_device *test_dev)
1128 kfree_const(test_dev->misc_dev.name);
1129 test_dev->misc_dev.name = NULL;
1130 free_test_dev_info(test_dev);
1131 kmod_config_free(test_dev);
1137 static struct kmod_test_device *register_test_dev_kmod(void)
1139 struct kmod_test_device *test_dev = NULL;
1142 mutex_lock(®_dev_mutex);
1144 /* int should suffice for number of devices, test for wrap */
1145 if (num_test_devs + 1 == INT_MAX) {
1146 pr_err("reached limit of number of test devices\n");
1150 test_dev = alloc_test_dev_kmod(num_test_devs);
1154 ret = misc_register(&test_dev->misc_dev);
1156 pr_err("could not register misc device: %d\n", ret);
1157 free_test_dev_kmod(test_dev);
1161 test_dev->dev = test_dev->misc_dev.this_device;
1162 list_add_tail(&test_dev->list, ®_test_devs);
1163 dev_info(test_dev->dev, "interface ready\n");
1168 mutex_unlock(®_dev_mutex);
1174 static int __init test_kmod_init(void)
1176 struct kmod_test_device *test_dev;
1179 test_dev = register_test_dev_kmod();
1181 pr_err("Cannot add first test kmod device\n");
1186 * With some work we might be able to gracefully enable
1187 * testing with this driver built-in, for now this seems
1188 * rather risky. For those willing to try have at it,
1189 * and enable the below. Good luck! If that works, try
1190 * lowering the init level for more fun.
1192 if (force_init_test) {
1193 ret = trigger_config_run_type(test_dev,
1194 TEST_KMOD_DRIVER, "tun");
1197 ret = trigger_config_run_type(test_dev,
1198 TEST_KMOD_FS_TYPE, "btrfs");
1205 late_initcall(test_kmod_init);
1208 void unregister_test_dev_kmod(struct kmod_test_device *test_dev)
1210 mutex_lock(&test_dev->trigger_mutex);
1211 mutex_lock(&test_dev->config_mutex);
1213 test_dev_kmod_stop_tests(test_dev);
1215 dev_info(test_dev->dev, "removing interface\n");
1216 misc_deregister(&test_dev->misc_dev);
1218 mutex_unlock(&test_dev->config_mutex);
1219 mutex_unlock(&test_dev->trigger_mutex);
1221 free_test_dev_kmod(test_dev);
1224 static void __exit test_kmod_exit(void)
1226 struct kmod_test_device *test_dev, *tmp;
1228 mutex_lock(®_dev_mutex);
1229 list_for_each_entry_safe(test_dev, tmp, ®_test_devs, list) {
1230 list_del(&test_dev->list);
1231 unregister_test_dev_kmod(test_dev);
1233 mutex_unlock(®_dev_mutex);
1235 module_exit(test_kmod_exit);
1237 MODULE_AUTHOR("Luis R. Rodriguez <mcgrof@kernel.org>");
1238 MODULE_LICENSE("GPL");