2 * This module provides an interface to trigger and test firmware loading.
4 * It is designed to be used for basic evaluation of the firmware loading
5 * subsystem (for example when validating firmware verification). It lacks
6 * any extra dependencies, and will not normally be loaded by the system
7 * unless explicitly requested by name.
10 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
12 #include <linux/init.h>
13 #include <linux/module.h>
14 #include <linux/printk.h>
15 #include <linux/completion.h>
16 #include <linux/firmware.h>
17 #include <linux/device.h>
19 #include <linux/miscdevice.h>
20 #include <linux/slab.h>
21 #include <linux/uaccess.h>
22 #include <linux/delay.h>
23 #include <linux/kthread.h>
24 #include <linux/vmalloc.h>
26 #define TEST_FIRMWARE_NAME "test-firmware.bin"
27 #define TEST_FIRMWARE_NUM_REQS 4
29 static DEFINE_MUTEX(test_fw_mutex);
30 static const struct firmware *test_firmware;
32 struct test_batched_req {
36 const struct firmware *fw;
38 struct completion completion;
39 struct task_struct *task;
44 * test_config - represents configuration for the test for different triggers
46 * @name: the name of the firmware file to look for
47 * @sync_direct: when the sync trigger is used if this is true
48 * request_firmware_direct() will be used instead.
49 * @send_uevent: whether or not to send a uevent for async requests
50 * @num_requests: number of requests to try per test case. This is trigger
52 * @reqs: stores all requests information
53 * @read_fw_idx: index of thread from which we want to read firmware results
54 * from through the read_fw trigger.
55 * @test_result: a test may use this to collect the result from the call
56 * of the request_firmware*() calls used in their tests. In order of
57 * priority we always keep first any setup error. If no setup errors were
58 * found then we move on to the first error encountered while running the
59 * API. Note that for async calls this typically will be a successful
60 * result (0) unless of course you've used bogus parameters, or the system
61 * is out of memory. In the async case the callback is expected to do a
62 * bit more homework to figure out what happened, unfortunately the only
63 * information passed today on error is the fact that no firmware was
64 * found so we can only assume -ENOENT on async calls if the firmware is
67 * Errors you can expect:
71 * 0: success for sync, for async it means request was sent
72 * -EINVAL: invalid parameters or request
73 * -ENOENT: files not found
77 * -ENOMEM: memory pressure on system
78 * -ENODEV: out of number of devices to test
79 * -EINVAL: an unexpected error has occurred
80 * @req_firmware: if @sync_direct is true this is set to
81 * request_firmware_direct(), otherwise request_firmware()
91 * These below don't belong her but we'll move them once we create
92 * a struct fw_test_device and stuff the misc_dev under there later.
94 struct test_batched_req *reqs;
96 int (*req_firmware)(const struct firmware **fw, const char *name,
97 struct device *device);
100 static struct test_config *test_fw_config;
102 static ssize_t test_fw_misc_read(struct file *f, char __user *buf,
103 size_t size, loff_t *offset)
107 mutex_lock(&test_fw_mutex);
109 rc = simple_read_from_buffer(buf, size, offset,
111 test_firmware->size);
112 mutex_unlock(&test_fw_mutex);
116 static const struct file_operations test_fw_fops = {
117 .owner = THIS_MODULE,
118 .read = test_fw_misc_read,
121 static void __test_release_all_firmware(void)
123 struct test_batched_req *req;
126 if (!test_fw_config->reqs)
129 for (i = 0; i < test_fw_config->num_requests; i++) {
130 req = &test_fw_config->reqs[i];
132 release_firmware(req->fw);
135 vfree(test_fw_config->reqs);
136 test_fw_config->reqs = NULL;
139 static void test_release_all_firmware(void)
141 mutex_lock(&test_fw_mutex);
142 __test_release_all_firmware();
143 mutex_unlock(&test_fw_mutex);
147 static void __test_firmware_config_free(void)
149 __test_release_all_firmware();
150 kfree_const(test_fw_config->name);
151 test_fw_config->name = NULL;
155 * XXX: move to kstrncpy() once merged.
157 * Users should use kfree_const() when freeing these.
159 static int __kstrncpy(char **dst, const char *name, size_t count, gfp_t gfp)
161 *dst = kstrndup(name, count, gfp);
167 static int __test_firmware_config_init(void)
171 ret = __kstrncpy(&test_fw_config->name, TEST_FIRMWARE_NAME,
172 strlen(TEST_FIRMWARE_NAME), GFP_KERNEL);
176 test_fw_config->num_requests = TEST_FIRMWARE_NUM_REQS;
177 test_fw_config->send_uevent = true;
178 test_fw_config->sync_direct = false;
179 test_fw_config->req_firmware = request_firmware;
180 test_fw_config->test_result = 0;
181 test_fw_config->reqs = NULL;
186 __test_firmware_config_free();
190 static ssize_t reset_store(struct device *dev,
191 struct device_attribute *attr,
192 const char *buf, size_t count)
196 mutex_lock(&test_fw_mutex);
198 __test_firmware_config_free();
200 ret = __test_firmware_config_init();
203 pr_err("could not alloc settings for config trigger: %d\n",
212 mutex_unlock(&test_fw_mutex);
216 static DEVICE_ATTR_WO(reset);
218 static ssize_t config_show(struct device *dev,
219 struct device_attribute *attr,
224 mutex_lock(&test_fw_mutex);
226 len += snprintf(buf, PAGE_SIZE,
227 "Custom trigger configuration for: %s\n",
230 if (test_fw_config->name)
231 len += snprintf(buf+len, PAGE_SIZE,
233 test_fw_config->name);
235 len += snprintf(buf+len, PAGE_SIZE,
238 len += snprintf(buf+len, PAGE_SIZE,
239 "num_requests:\t%u\n", test_fw_config->num_requests);
241 len += snprintf(buf+len, PAGE_SIZE,
242 "send_uevent:\t\t%s\n",
243 test_fw_config->send_uevent ?
244 "FW_ACTION_HOTPLUG" :
245 "FW_ACTION_NOHOTPLUG");
246 len += snprintf(buf+len, PAGE_SIZE,
247 "sync_direct:\t\t%s\n",
248 test_fw_config->sync_direct ? "true" : "false");
249 len += snprintf(buf+len, PAGE_SIZE,
250 "read_fw_idx:\t%u\n", test_fw_config->read_fw_idx);
252 mutex_unlock(&test_fw_mutex);
256 static DEVICE_ATTR_RO(config);
258 static ssize_t config_name_store(struct device *dev,
259 struct device_attribute *attr,
260 const char *buf, size_t count)
264 mutex_lock(&test_fw_mutex);
265 kfree_const(test_fw_config->name);
266 ret = __kstrncpy(&test_fw_config->name, buf, count, GFP_KERNEL);
267 mutex_unlock(&test_fw_mutex);
273 * As per sysfs_kf_seq_show() the buf is max PAGE_SIZE.
275 static ssize_t config_test_show_str(char *dst,
280 mutex_lock(&test_fw_mutex);
281 len = snprintf(dst, PAGE_SIZE, "%s\n", src);
282 mutex_unlock(&test_fw_mutex);
287 static int test_dev_config_update_bool(const char *buf, size_t size,
292 mutex_lock(&test_fw_mutex);
293 if (strtobool(buf, cfg) < 0)
297 mutex_unlock(&test_fw_mutex);
303 test_dev_config_show_bool(char *buf,
308 mutex_lock(&test_fw_mutex);
310 mutex_unlock(&test_fw_mutex);
312 return snprintf(buf, PAGE_SIZE, "%d\n", val);
315 static ssize_t test_dev_config_show_int(char *buf, int cfg)
319 mutex_lock(&test_fw_mutex);
321 mutex_unlock(&test_fw_mutex);
323 return snprintf(buf, PAGE_SIZE, "%d\n", val);
326 static int test_dev_config_update_u8(const char *buf, size_t size, u8 *cfg)
331 ret = kstrtol(buf, 10, &new);
338 mutex_lock(&test_fw_mutex);
340 mutex_unlock(&test_fw_mutex);
342 /* Always return full write size even if we didn't consume all */
346 static ssize_t test_dev_config_show_u8(char *buf, u8 cfg)
350 mutex_lock(&test_fw_mutex);
352 mutex_unlock(&test_fw_mutex);
354 return snprintf(buf, PAGE_SIZE, "%u\n", val);
357 static ssize_t config_name_show(struct device *dev,
358 struct device_attribute *attr,
361 return config_test_show_str(buf, test_fw_config->name);
363 static DEVICE_ATTR_RW(config_name);
365 static ssize_t config_num_requests_store(struct device *dev,
366 struct device_attribute *attr,
367 const char *buf, size_t count)
371 mutex_lock(&test_fw_mutex);
372 if (test_fw_config->reqs) {
373 pr_err("Must call release_all_firmware prior to changing config\n");
375 mutex_unlock(&test_fw_mutex);
378 mutex_unlock(&test_fw_mutex);
380 rc = test_dev_config_update_u8(buf, count,
381 &test_fw_config->num_requests);
387 static ssize_t config_num_requests_show(struct device *dev,
388 struct device_attribute *attr,
391 return test_dev_config_show_u8(buf, test_fw_config->num_requests);
393 static DEVICE_ATTR_RW(config_num_requests);
395 static ssize_t config_sync_direct_store(struct device *dev,
396 struct device_attribute *attr,
397 const char *buf, size_t count)
399 int rc = test_dev_config_update_bool(buf, count,
400 &test_fw_config->sync_direct);
403 test_fw_config->req_firmware = test_fw_config->sync_direct ?
404 request_firmware_direct :
409 static ssize_t config_sync_direct_show(struct device *dev,
410 struct device_attribute *attr,
413 return test_dev_config_show_bool(buf, test_fw_config->sync_direct);
415 static DEVICE_ATTR_RW(config_sync_direct);
417 static ssize_t config_send_uevent_store(struct device *dev,
418 struct device_attribute *attr,
419 const char *buf, size_t count)
421 return test_dev_config_update_bool(buf, count,
422 &test_fw_config->send_uevent);
425 static ssize_t config_send_uevent_show(struct device *dev,
426 struct device_attribute *attr,
429 return test_dev_config_show_bool(buf, test_fw_config->send_uevent);
431 static DEVICE_ATTR_RW(config_send_uevent);
433 static ssize_t config_read_fw_idx_store(struct device *dev,
434 struct device_attribute *attr,
435 const char *buf, size_t count)
437 return test_dev_config_update_u8(buf, count,
438 &test_fw_config->read_fw_idx);
441 static ssize_t config_read_fw_idx_show(struct device *dev,
442 struct device_attribute *attr,
445 return test_dev_config_show_u8(buf, test_fw_config->read_fw_idx);
447 static DEVICE_ATTR_RW(config_read_fw_idx);
450 static ssize_t trigger_request_store(struct device *dev,
451 struct device_attribute *attr,
452 const char *buf, size_t count)
457 name = kstrndup(buf, count, GFP_KERNEL);
461 pr_info("loading '%s'\n", name);
463 mutex_lock(&test_fw_mutex);
464 release_firmware(test_firmware);
465 test_firmware = NULL;
466 rc = request_firmware(&test_firmware, name, dev);
468 pr_info("load of '%s' failed: %d\n", name, rc);
471 pr_info("loaded: %zu\n", test_firmware->size);
475 mutex_unlock(&test_fw_mutex);
481 static DEVICE_ATTR_WO(trigger_request);
483 static DECLARE_COMPLETION(async_fw_done);
485 static void trigger_async_request_cb(const struct firmware *fw, void *context)
488 complete(&async_fw_done);
491 static ssize_t trigger_async_request_store(struct device *dev,
492 struct device_attribute *attr,
493 const char *buf, size_t count)
498 name = kstrndup(buf, count, GFP_KERNEL);
502 pr_info("loading '%s'\n", name);
504 mutex_lock(&test_fw_mutex);
505 release_firmware(test_firmware);
506 test_firmware = NULL;
507 rc = request_firmware_nowait(THIS_MODULE, 1, name, dev, GFP_KERNEL,
508 NULL, trigger_async_request_cb);
510 pr_info("async load of '%s' failed: %d\n", name, rc);
514 /* Free 'name' ASAP, to test for race conditions */
517 wait_for_completion(&async_fw_done);
520 pr_info("loaded: %zu\n", test_firmware->size);
523 pr_err("failed to async load firmware\n");
528 mutex_unlock(&test_fw_mutex);
532 static DEVICE_ATTR_WO(trigger_async_request);
534 static ssize_t trigger_custom_fallback_store(struct device *dev,
535 struct device_attribute *attr,
536 const char *buf, size_t count)
541 name = kstrndup(buf, count, GFP_KERNEL);
545 pr_info("loading '%s' using custom fallback mechanism\n", name);
547 mutex_lock(&test_fw_mutex);
548 release_firmware(test_firmware);
549 test_firmware = NULL;
550 rc = request_firmware_nowait(THIS_MODULE, FW_ACTION_NOHOTPLUG, name,
551 dev, GFP_KERNEL, NULL,
552 trigger_async_request_cb);
554 pr_info("async load of '%s' failed: %d\n", name, rc);
558 /* Free 'name' ASAP, to test for race conditions */
561 wait_for_completion(&async_fw_done);
564 pr_info("loaded: %zu\n", test_firmware->size);
567 pr_err("failed to async load firmware\n");
572 mutex_unlock(&test_fw_mutex);
576 static DEVICE_ATTR_WO(trigger_custom_fallback);
578 static int test_fw_run_batch_request(void *data)
580 struct test_batched_req *req = data;
583 test_fw_config->test_result = -EINVAL;
587 req->rc = test_fw_config->req_firmware(&req->fw, req->name, req->dev);
589 pr_info("#%u: batched sync load failed: %d\n",
591 if (!test_fw_config->test_result)
592 test_fw_config->test_result = req->rc;
593 } else if (req->fw) {
595 pr_info("#%u: batched sync loaded %zu\n",
596 req->idx, req->fw->size);
598 complete(&req->completion);
606 * We use a kthread as otherwise the kernel serializes all our sync requests
607 * and we would not be able to mimic batched requests on a sync call. Batched
608 * requests on a sync call can for instance happen on a device driver when
609 * multiple cards are used and firmware loading happens outside of probe.
611 static ssize_t trigger_batched_requests_store(struct device *dev,
612 struct device_attribute *attr,
613 const char *buf, size_t count)
615 struct test_batched_req *req;
619 mutex_lock(&test_fw_mutex);
621 test_fw_config->reqs =
622 vzalloc(array3_size(sizeof(struct test_batched_req),
623 test_fw_config->num_requests, 2));
624 if (!test_fw_config->reqs) {
629 pr_info("batched sync firmware loading '%s' %u times\n",
630 test_fw_config->name, test_fw_config->num_requests);
632 for (i = 0; i < test_fw_config->num_requests; i++) {
633 req = &test_fw_config->reqs[i];
641 req->name = test_fw_config->name;
643 init_completion(&req->completion);
644 req->task = kthread_run(test_fw_run_batch_request, req,
645 "%s-%u", KBUILD_MODNAME, req->idx);
646 if (!req->task || IS_ERR(req->task)) {
647 pr_err("Setting up thread %u failed\n", req->idx);
657 * We require an explicit release to enable more time and delay of
658 * calling release_firmware() to improve our chances of forcing a
659 * batched request. If we instead called release_firmware() right away
660 * then we might miss on an opportunity of having a successful firmware
661 * request pass on the opportunity to be come a batched request.
665 for (i = 0; i < test_fw_config->num_requests; i++) {
666 req = &test_fw_config->reqs[i];
667 if (req->task || req->sent)
668 wait_for_completion(&req->completion);
671 /* Override any worker error if we had a general setup error */
673 test_fw_config->test_result = rc;
676 mutex_unlock(&test_fw_mutex);
680 static DEVICE_ATTR_WO(trigger_batched_requests);
683 * We wait for each callback to return with the lock held, no need to lock here
685 static void trigger_batched_cb(const struct firmware *fw, void *context)
687 struct test_batched_req *req = context;
690 test_fw_config->test_result = -EINVAL;
694 /* forces *some* batched requests to queue up */
701 * Unfortunately the firmware API gives us nothing other than a null FW
702 * if the firmware was not found on async requests. Best we can do is
703 * just assume -ENOENT. A better API would pass the actual return
704 * value to the callback.
706 if (!fw && !test_fw_config->test_result)
707 test_fw_config->test_result = -ENOENT;
709 complete(&req->completion);
713 ssize_t trigger_batched_requests_async_store(struct device *dev,
714 struct device_attribute *attr,
715 const char *buf, size_t count)
717 struct test_batched_req *req;
722 mutex_lock(&test_fw_mutex);
724 test_fw_config->reqs =
725 vzalloc(array3_size(sizeof(struct test_batched_req),
726 test_fw_config->num_requests, 2));
727 if (!test_fw_config->reqs) {
732 pr_info("batched loading '%s' custom fallback mechanism %u times\n",
733 test_fw_config->name, test_fw_config->num_requests);
735 send_uevent = test_fw_config->send_uevent ? FW_ACTION_HOTPLUG :
738 for (i = 0; i < test_fw_config->num_requests; i++) {
739 req = &test_fw_config->reqs[i];
744 req->name = test_fw_config->name;
747 init_completion(&req->completion);
748 rc = request_firmware_nowait(THIS_MODULE, send_uevent,
750 dev, GFP_KERNEL, req,
753 pr_info("#%u: batched async load failed setup: %d\n",
766 * We require an explicit release to enable more time and delay of
767 * calling release_firmware() to improve our chances of forcing a
768 * batched request. If we instead called release_firmware() right away
769 * then we might miss on an opportunity of having a successful firmware
770 * request pass on the opportunity to be come a batched request.
773 for (i = 0; i < test_fw_config->num_requests; i++) {
774 req = &test_fw_config->reqs[i];
776 wait_for_completion(&req->completion);
779 /* Override any worker error if we had a general setup error */
781 test_fw_config->test_result = rc;
784 mutex_unlock(&test_fw_mutex);
788 static DEVICE_ATTR_WO(trigger_batched_requests_async);
790 static ssize_t test_result_show(struct device *dev,
791 struct device_attribute *attr,
794 return test_dev_config_show_int(buf, test_fw_config->test_result);
796 static DEVICE_ATTR_RO(test_result);
798 static ssize_t release_all_firmware_store(struct device *dev,
799 struct device_attribute *attr,
800 const char *buf, size_t count)
802 test_release_all_firmware();
805 static DEVICE_ATTR_WO(release_all_firmware);
807 static ssize_t read_firmware_show(struct device *dev,
808 struct device_attribute *attr,
811 struct test_batched_req *req;
815 mutex_lock(&test_fw_mutex);
817 idx = test_fw_config->read_fw_idx;
818 if (idx >= test_fw_config->num_requests) {
823 if (!test_fw_config->reqs) {
828 req = &test_fw_config->reqs[idx];
830 pr_err("#%u: failed to async load firmware\n", idx);
835 pr_info("#%u: loaded %zu\n", idx, req->fw->size);
837 if (req->fw->size > PAGE_SIZE) {
838 pr_err("Testing interface must use PAGE_SIZE firmware for now\n");
842 memcpy(buf, req->fw->data, req->fw->size);
846 mutex_unlock(&test_fw_mutex);
850 static DEVICE_ATTR_RO(read_firmware);
852 #define TEST_FW_DEV_ATTR(name) &dev_attr_##name.attr
854 static struct attribute *test_dev_attrs[] = {
855 TEST_FW_DEV_ATTR(reset),
857 TEST_FW_DEV_ATTR(config),
858 TEST_FW_DEV_ATTR(config_name),
859 TEST_FW_DEV_ATTR(config_num_requests),
860 TEST_FW_DEV_ATTR(config_sync_direct),
861 TEST_FW_DEV_ATTR(config_send_uevent),
862 TEST_FW_DEV_ATTR(config_read_fw_idx),
864 /* These don't use the config at all - they could be ported! */
865 TEST_FW_DEV_ATTR(trigger_request),
866 TEST_FW_DEV_ATTR(trigger_async_request),
867 TEST_FW_DEV_ATTR(trigger_custom_fallback),
869 /* These use the config and can use the test_result */
870 TEST_FW_DEV_ATTR(trigger_batched_requests),
871 TEST_FW_DEV_ATTR(trigger_batched_requests_async),
873 TEST_FW_DEV_ATTR(release_all_firmware),
874 TEST_FW_DEV_ATTR(test_result),
875 TEST_FW_DEV_ATTR(read_firmware),
879 ATTRIBUTE_GROUPS(test_dev);
881 static struct miscdevice test_fw_misc_device = {
882 .minor = MISC_DYNAMIC_MINOR,
883 .name = "test_firmware",
884 .fops = &test_fw_fops,
885 .groups = test_dev_groups,
888 static int __init test_firmware_init(void)
892 test_fw_config = kzalloc(sizeof(struct test_config), GFP_KERNEL);
896 rc = __test_firmware_config_init();
900 rc = misc_register(&test_fw_misc_device);
902 kfree(test_fw_config);
903 pr_err("could not register misc device: %d\n", rc);
907 pr_warn("interface ready\n");
912 module_init(test_firmware_init);
914 static void __exit test_firmware_exit(void)
916 mutex_lock(&test_fw_mutex);
917 release_firmware(test_firmware);
918 misc_deregister(&test_fw_misc_device);
919 __test_firmware_config_free();
920 kfree(test_fw_config);
921 mutex_unlock(&test_fw_mutex);
923 pr_warn("removed interface\n");
926 module_exit(test_firmware_exit);
928 MODULE_AUTHOR("Kees Cook <keescook@chromium.org>");
929 MODULE_LICENSE("GPL");