1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * This module provides an interface to trigger and test firmware loading.
4 *
5 * It is designed to be used for basic evaluation of the firmware loading
6 * subsystem (for example when validating firmware verification). It lacks
7 * any extra dependencies, and will not normally be loaded by the system
8 * unless explicitly requested by name.
9 */
10
11 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
12
13 #include <linux/init.h>
14 #include <linux/module.h>
15 #include <linux/printk.h>
16 #include <linux/completion.h>
17 #include <linux/firmware.h>
18 #include <linux/device.h>
19 #include <linux/fs.h>
20 #include <linux/miscdevice.h>
21 #include <linux/sizes.h>
22 #include <linux/slab.h>
23 #include <linux/uaccess.h>
24 #include <linux/delay.h>
25 #include <linux/kthread.h>
26 #include <linux/vmalloc.h>
27
28 #define TEST_FIRMWARE_NAME "test-firmware.bin"
29 #define TEST_FIRMWARE_NUM_REQS 4
30 #define TEST_FIRMWARE_BUF_SIZE SZ_1K
31
32 static DEFINE_MUTEX(test_fw_mutex);
33 static const struct firmware *test_firmware;
34
35 struct test_batched_req {
36 u8 idx;
37 int rc;
38 bool sent;
39 const struct firmware *fw;
40 const char *name;
41 struct completion completion;
42 struct task_struct *task;
43 struct device *dev;
44 };
45
46 /**
47 * test_config - represents configuration for the test for different triggers
48 *
49 * @name: the name of the firmware file to look for
50 * @into_buf: when the into_buf is used if this is true
51 * request_firmware_into_buf() will be used instead.
52 * @sync_direct: when the sync trigger is used if this is true
53 * request_firmware_direct() will be used instead.
54 * @send_uevent: whether or not to send a uevent for async requests
55 * @num_requests: number of requests to try per test case. This is trigger
56 * specific.
57 * @reqs: stores all requests information
58 * @read_fw_idx: index of thread from which we want to read firmware results
59 * from through the read_fw trigger.
60 * @test_result: a test may use this to collect the result from the call
61 * of the request_firmware*() calls used in their tests. In order of
62 * priority we always keep first any setup error. If no setup errors were
63 * found then we move on to the first error encountered while running the
64 * API. Note that for async calls this typically will be a successful
65 * result (0) unless of course you've used bogus parameters, or the system
66 * is out of memory. In the async case the callback is expected to do a
67 * bit more homework to figure out what happened, unfortunately the only
68 * information passed today on error is the fact that no firmware was
69 * found so we can only assume -ENOENT on async calls if the firmware is
70 * NULL.
71 *
72 * Errors you can expect:
73 *
74 * API specific:
75 *
76 * 0: success for sync, for async it means request was sent
77 * -EINVAL: invalid parameters or request
78 * -ENOENT: files not found
79 *
80 * System environment:
81 *
82 * -ENOMEM: memory pressure on system
83 * -ENODEV: out of number of devices to test
84 * -EINVAL: an unexpected error has occurred
85 * @req_firmware: if @sync_direct is true this is set to
86 * request_firmware_direct(), otherwise request_firmware()
87 */
88 struct test_config {
89 char *name;
90 bool into_buf;
91 bool sync_direct;
92 bool send_uevent;
93 u8 num_requests;
94 u8 read_fw_idx;
95
96 /*
97 * These below don't belong her but we'll move them once we create
98 * a struct fw_test_device and stuff the misc_dev under there later.
99 */
100 struct test_batched_req *reqs;
101 int test_result;
102 int (*req_firmware)(const struct firmware **fw, const char *name,
103 struct device *device);
104 };
105
106 static struct test_config *test_fw_config;
107
test_fw_misc_read(struct file * f,char __user * buf,size_t size,loff_t * offset)108 static ssize_t test_fw_misc_read(struct file *f, char __user *buf,
109 size_t size, loff_t *offset)
110 {
111 ssize_t rc = 0;
112
113 mutex_lock(&test_fw_mutex);
114 if (test_firmware)
115 rc = simple_read_from_buffer(buf, size, offset,
116 test_firmware->data,
117 test_firmware->size);
118 mutex_unlock(&test_fw_mutex);
119 return rc;
120 }
121
122 static const struct file_operations test_fw_fops = {
123 .owner = THIS_MODULE,
124 .read = test_fw_misc_read,
125 };
126
__test_release_all_firmware(void)127 static void __test_release_all_firmware(void)
128 {
129 struct test_batched_req *req;
130 u8 i;
131
132 if (!test_fw_config->reqs)
133 return;
134
135 for (i = 0; i < test_fw_config->num_requests; i++) {
136 req = &test_fw_config->reqs[i];
137 if (req->fw)
138 release_firmware(req->fw);
139 }
140
141 vfree(test_fw_config->reqs);
142 test_fw_config->reqs = NULL;
143 }
144
test_release_all_firmware(void)145 static void test_release_all_firmware(void)
146 {
147 mutex_lock(&test_fw_mutex);
148 __test_release_all_firmware();
149 mutex_unlock(&test_fw_mutex);
150 }
151
152
__test_firmware_config_free(void)153 static void __test_firmware_config_free(void)
154 {
155 __test_release_all_firmware();
156 kfree_const(test_fw_config->name);
157 test_fw_config->name = NULL;
158 }
159
160 /*
161 * XXX: move to kstrncpy() once merged.
162 *
163 * Users should use kfree_const() when freeing these.
164 */
__kstrncpy(char ** dst,const char * name,size_t count,gfp_t gfp)165 static int __kstrncpy(char **dst, const char *name, size_t count, gfp_t gfp)
166 {
167 *dst = kstrndup(name, count, gfp);
168 if (!*dst)
169 return -ENOSPC;
170 return count;
171 }
172
__test_firmware_config_init(void)173 static int __test_firmware_config_init(void)
174 {
175 int ret;
176
177 ret = __kstrncpy(&test_fw_config->name, TEST_FIRMWARE_NAME,
178 strlen(TEST_FIRMWARE_NAME), GFP_KERNEL);
179 if (ret < 0)
180 goto out;
181
182 test_fw_config->num_requests = TEST_FIRMWARE_NUM_REQS;
183 test_fw_config->send_uevent = true;
184 test_fw_config->into_buf = false;
185 test_fw_config->sync_direct = false;
186 test_fw_config->req_firmware = request_firmware;
187 test_fw_config->test_result = 0;
188 test_fw_config->reqs = NULL;
189
190 return 0;
191
192 out:
193 __test_firmware_config_free();
194 return ret;
195 }
196
reset_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)197 static ssize_t reset_store(struct device *dev,
198 struct device_attribute *attr,
199 const char *buf, size_t count)
200 {
201 int ret;
202
203 mutex_lock(&test_fw_mutex);
204
205 __test_firmware_config_free();
206
207 ret = __test_firmware_config_init();
208 if (ret < 0) {
209 ret = -ENOMEM;
210 pr_err("could not alloc settings for config trigger: %d\n",
211 ret);
212 goto out;
213 }
214
215 pr_info("reset\n");
216 ret = count;
217
218 out:
219 mutex_unlock(&test_fw_mutex);
220
221 return ret;
222 }
223 static DEVICE_ATTR_WO(reset);
224
config_show(struct device * dev,struct device_attribute * attr,char * buf)225 static ssize_t config_show(struct device *dev,
226 struct device_attribute *attr,
227 char *buf)
228 {
229 int len = 0;
230
231 mutex_lock(&test_fw_mutex);
232
233 len += scnprintf(buf, PAGE_SIZE - len,
234 "Custom trigger configuration for: %s\n",
235 dev_name(dev));
236
237 if (test_fw_config->name)
238 len += scnprintf(buf+len, PAGE_SIZE - len,
239 "name:\t%s\n",
240 test_fw_config->name);
241 else
242 len += scnprintf(buf+len, PAGE_SIZE - len,
243 "name:\tEMTPY\n");
244
245 len += scnprintf(buf+len, PAGE_SIZE - len,
246 "num_requests:\t%u\n", test_fw_config->num_requests);
247
248 len += scnprintf(buf+len, PAGE_SIZE - len,
249 "send_uevent:\t\t%s\n",
250 test_fw_config->send_uevent ?
251 "FW_ACTION_HOTPLUG" :
252 "FW_ACTION_NOHOTPLUG");
253 len += scnprintf(buf+len, PAGE_SIZE - len,
254 "into_buf:\t\t%s\n",
255 test_fw_config->into_buf ? "true" : "false");
256 len += scnprintf(buf+len, PAGE_SIZE - len,
257 "sync_direct:\t\t%s\n",
258 test_fw_config->sync_direct ? "true" : "false");
259 len += scnprintf(buf+len, PAGE_SIZE - len,
260 "read_fw_idx:\t%u\n", test_fw_config->read_fw_idx);
261
262 mutex_unlock(&test_fw_mutex);
263
264 return len;
265 }
266 static DEVICE_ATTR_RO(config);
267
config_name_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)268 static ssize_t config_name_store(struct device *dev,
269 struct device_attribute *attr,
270 const char *buf, size_t count)
271 {
272 int ret;
273
274 mutex_lock(&test_fw_mutex);
275 kfree_const(test_fw_config->name);
276 ret = __kstrncpy(&test_fw_config->name, buf, count, GFP_KERNEL);
277 mutex_unlock(&test_fw_mutex);
278
279 return ret;
280 }
281
282 /*
283 * As per sysfs_kf_seq_show() the buf is max PAGE_SIZE.
284 */
config_test_show_str(char * dst,char * src)285 static ssize_t config_test_show_str(char *dst,
286 char *src)
287 {
288 int len;
289
290 mutex_lock(&test_fw_mutex);
291 len = snprintf(dst, PAGE_SIZE, "%s\n", src);
292 mutex_unlock(&test_fw_mutex);
293
294 return len;
295 }
296
test_dev_config_update_bool(const char * buf,size_t size,bool * cfg)297 static int test_dev_config_update_bool(const char *buf, size_t size,
298 bool *cfg)
299 {
300 int ret;
301
302 mutex_lock(&test_fw_mutex);
303 if (strtobool(buf, cfg) < 0)
304 ret = -EINVAL;
305 else
306 ret = size;
307 mutex_unlock(&test_fw_mutex);
308
309 return ret;
310 }
311
312 static ssize_t
test_dev_config_show_bool(char * buf,bool config)313 test_dev_config_show_bool(char *buf,
314 bool config)
315 {
316 bool val;
317
318 mutex_lock(&test_fw_mutex);
319 val = config;
320 mutex_unlock(&test_fw_mutex);
321
322 return snprintf(buf, PAGE_SIZE, "%d\n", val);
323 }
324
test_dev_config_show_int(char * buf,int cfg)325 static ssize_t test_dev_config_show_int(char *buf, int cfg)
326 {
327 int val;
328
329 mutex_lock(&test_fw_mutex);
330 val = cfg;
331 mutex_unlock(&test_fw_mutex);
332
333 return snprintf(buf, PAGE_SIZE, "%d\n", val);
334 }
335
test_dev_config_update_u8(const char * buf,size_t size,u8 * cfg)336 static int test_dev_config_update_u8(const char *buf, size_t size, u8 *cfg)
337 {
338 int ret;
339 long new;
340
341 ret = kstrtol(buf, 10, &new);
342 if (ret)
343 return ret;
344
345 if (new > U8_MAX)
346 return -EINVAL;
347
348 mutex_lock(&test_fw_mutex);
349 *(u8 *)cfg = new;
350 mutex_unlock(&test_fw_mutex);
351
352 /* Always return full write size even if we didn't consume all */
353 return size;
354 }
355
test_dev_config_show_u8(char * buf,u8 cfg)356 static ssize_t test_dev_config_show_u8(char *buf, u8 cfg)
357 {
358 u8 val;
359
360 mutex_lock(&test_fw_mutex);
361 val = cfg;
362 mutex_unlock(&test_fw_mutex);
363
364 return snprintf(buf, PAGE_SIZE, "%u\n", val);
365 }
366
config_name_show(struct device * dev,struct device_attribute * attr,char * buf)367 static ssize_t config_name_show(struct device *dev,
368 struct device_attribute *attr,
369 char *buf)
370 {
371 return config_test_show_str(buf, test_fw_config->name);
372 }
373 static DEVICE_ATTR_RW(config_name);
374
config_num_requests_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)375 static ssize_t config_num_requests_store(struct device *dev,
376 struct device_attribute *attr,
377 const char *buf, size_t count)
378 {
379 int rc;
380
381 mutex_lock(&test_fw_mutex);
382 if (test_fw_config->reqs) {
383 pr_err("Must call release_all_firmware prior to changing config\n");
384 rc = -EINVAL;
385 mutex_unlock(&test_fw_mutex);
386 goto out;
387 }
388 mutex_unlock(&test_fw_mutex);
389
390 rc = test_dev_config_update_u8(buf, count,
391 &test_fw_config->num_requests);
392
393 out:
394 return rc;
395 }
396
config_num_requests_show(struct device * dev,struct device_attribute * attr,char * buf)397 static ssize_t config_num_requests_show(struct device *dev,
398 struct device_attribute *attr,
399 char *buf)
400 {
401 return test_dev_config_show_u8(buf, test_fw_config->num_requests);
402 }
403 static DEVICE_ATTR_RW(config_num_requests);
404
config_into_buf_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)405 static ssize_t config_into_buf_store(struct device *dev,
406 struct device_attribute *attr,
407 const char *buf, size_t count)
408 {
409 return test_dev_config_update_bool(buf,
410 count,
411 &test_fw_config->into_buf);
412 }
413
config_into_buf_show(struct device * dev,struct device_attribute * attr,char * buf)414 static ssize_t config_into_buf_show(struct device *dev,
415 struct device_attribute *attr,
416 char *buf)
417 {
418 return test_dev_config_show_bool(buf, test_fw_config->into_buf);
419 }
420 static DEVICE_ATTR_RW(config_into_buf);
421
config_sync_direct_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)422 static ssize_t config_sync_direct_store(struct device *dev,
423 struct device_attribute *attr,
424 const char *buf, size_t count)
425 {
426 int rc = test_dev_config_update_bool(buf, count,
427 &test_fw_config->sync_direct);
428
429 if (rc == count)
430 test_fw_config->req_firmware = test_fw_config->sync_direct ?
431 request_firmware_direct :
432 request_firmware;
433 return rc;
434 }
435
config_sync_direct_show(struct device * dev,struct device_attribute * attr,char * buf)436 static ssize_t config_sync_direct_show(struct device *dev,
437 struct device_attribute *attr,
438 char *buf)
439 {
440 return test_dev_config_show_bool(buf, test_fw_config->sync_direct);
441 }
442 static DEVICE_ATTR_RW(config_sync_direct);
443
config_send_uevent_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)444 static ssize_t config_send_uevent_store(struct device *dev,
445 struct device_attribute *attr,
446 const char *buf, size_t count)
447 {
448 return test_dev_config_update_bool(buf, count,
449 &test_fw_config->send_uevent);
450 }
451
config_send_uevent_show(struct device * dev,struct device_attribute * attr,char * buf)452 static ssize_t config_send_uevent_show(struct device *dev,
453 struct device_attribute *attr,
454 char *buf)
455 {
456 return test_dev_config_show_bool(buf, test_fw_config->send_uevent);
457 }
458 static DEVICE_ATTR_RW(config_send_uevent);
459
config_read_fw_idx_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)460 static ssize_t config_read_fw_idx_store(struct device *dev,
461 struct device_attribute *attr,
462 const char *buf, size_t count)
463 {
464 return test_dev_config_update_u8(buf, count,
465 &test_fw_config->read_fw_idx);
466 }
467
config_read_fw_idx_show(struct device * dev,struct device_attribute * attr,char * buf)468 static ssize_t config_read_fw_idx_show(struct device *dev,
469 struct device_attribute *attr,
470 char *buf)
471 {
472 return test_dev_config_show_u8(buf, test_fw_config->read_fw_idx);
473 }
474 static DEVICE_ATTR_RW(config_read_fw_idx);
475
476
trigger_request_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)477 static ssize_t trigger_request_store(struct device *dev,
478 struct device_attribute *attr,
479 const char *buf, size_t count)
480 {
481 int rc;
482 char *name;
483
484 name = kstrndup(buf, count, GFP_KERNEL);
485 if (!name)
486 return -ENOSPC;
487
488 pr_info("loading '%s'\n", name);
489
490 mutex_lock(&test_fw_mutex);
491 release_firmware(test_firmware);
492 test_firmware = NULL;
493 rc = request_firmware(&test_firmware, name, dev);
494 if (rc) {
495 pr_info("load of '%s' failed: %d\n", name, rc);
496 goto out;
497 }
498 pr_info("loaded: %zu\n", test_firmware->size);
499 rc = count;
500
501 out:
502 mutex_unlock(&test_fw_mutex);
503
504 kfree(name);
505
506 return rc;
507 }
508 static DEVICE_ATTR_WO(trigger_request);
509
510 static DECLARE_COMPLETION(async_fw_done);
511
trigger_async_request_cb(const struct firmware * fw,void * context)512 static void trigger_async_request_cb(const struct firmware *fw, void *context)
513 {
514 test_firmware = fw;
515 complete(&async_fw_done);
516 }
517
trigger_async_request_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)518 static ssize_t trigger_async_request_store(struct device *dev,
519 struct device_attribute *attr,
520 const char *buf, size_t count)
521 {
522 int rc;
523 char *name;
524
525 name = kstrndup(buf, count, GFP_KERNEL);
526 if (!name)
527 return -ENOSPC;
528
529 pr_info("loading '%s'\n", name);
530
531 mutex_lock(&test_fw_mutex);
532 release_firmware(test_firmware);
533 test_firmware = NULL;
534 rc = request_firmware_nowait(THIS_MODULE, 1, name, dev, GFP_KERNEL,
535 NULL, trigger_async_request_cb);
536 if (rc) {
537 pr_info("async load of '%s' failed: %d\n", name, rc);
538 kfree(name);
539 goto out;
540 }
541 /* Free 'name' ASAP, to test for race conditions */
542 kfree(name);
543
544 wait_for_completion(&async_fw_done);
545
546 if (test_firmware) {
547 pr_info("loaded: %zu\n", test_firmware->size);
548 rc = count;
549 } else {
550 pr_err("failed to async load firmware\n");
551 rc = -ENOMEM;
552 }
553
554 out:
555 mutex_unlock(&test_fw_mutex);
556
557 return rc;
558 }
559 static DEVICE_ATTR_WO(trigger_async_request);
560
trigger_custom_fallback_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)561 static ssize_t trigger_custom_fallback_store(struct device *dev,
562 struct device_attribute *attr,
563 const char *buf, size_t count)
564 {
565 int rc;
566 char *name;
567
568 name = kstrndup(buf, count, GFP_KERNEL);
569 if (!name)
570 return -ENOSPC;
571
572 pr_info("loading '%s' using custom fallback mechanism\n", name);
573
574 mutex_lock(&test_fw_mutex);
575 release_firmware(test_firmware);
576 test_firmware = NULL;
577 rc = request_firmware_nowait(THIS_MODULE, FW_ACTION_NOHOTPLUG, name,
578 dev, GFP_KERNEL, NULL,
579 trigger_async_request_cb);
580 if (rc) {
581 pr_info("async load of '%s' failed: %d\n", name, rc);
582 kfree(name);
583 goto out;
584 }
585 /* Free 'name' ASAP, to test for race conditions */
586 kfree(name);
587
588 wait_for_completion(&async_fw_done);
589
590 if (test_firmware) {
591 pr_info("loaded: %zu\n", test_firmware->size);
592 rc = count;
593 } else {
594 pr_err("failed to async load firmware\n");
595 rc = -ENODEV;
596 }
597
598 out:
599 mutex_unlock(&test_fw_mutex);
600
601 return rc;
602 }
603 static DEVICE_ATTR_WO(trigger_custom_fallback);
604
test_fw_run_batch_request(void * data)605 static int test_fw_run_batch_request(void *data)
606 {
607 struct test_batched_req *req = data;
608
609 if (!req) {
610 test_fw_config->test_result = -EINVAL;
611 return -EINVAL;
612 }
613
614 if (test_fw_config->into_buf) {
615 void *test_buf;
616
617 test_buf = kzalloc(TEST_FIRMWARE_BUF_SIZE, GFP_KERNEL);
618 if (!test_buf)
619 return -ENOSPC;
620
621 req->rc = request_firmware_into_buf(&req->fw,
622 req->name,
623 req->dev,
624 test_buf,
625 TEST_FIRMWARE_BUF_SIZE);
626 if (!req->fw)
627 kfree(test_buf);
628 } else {
629 req->rc = test_fw_config->req_firmware(&req->fw,
630 req->name,
631 req->dev);
632 }
633
634 if (req->rc) {
635 pr_info("#%u: batched sync load failed: %d\n",
636 req->idx, req->rc);
637 if (!test_fw_config->test_result)
638 test_fw_config->test_result = req->rc;
639 } else if (req->fw) {
640 req->sent = true;
641 pr_info("#%u: batched sync loaded %zu\n",
642 req->idx, req->fw->size);
643 }
644 complete(&req->completion);
645
646 req->task = NULL;
647
648 return 0;
649 }
650
651 /*
652 * We use a kthread as otherwise the kernel serializes all our sync requests
653 * and we would not be able to mimic batched requests on a sync call. Batched
654 * requests on a sync call can for instance happen on a device driver when
655 * multiple cards are used and firmware loading happens outside of probe.
656 */
trigger_batched_requests_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)657 static ssize_t trigger_batched_requests_store(struct device *dev,
658 struct device_attribute *attr,
659 const char *buf, size_t count)
660 {
661 struct test_batched_req *req;
662 int rc;
663 u8 i;
664
665 mutex_lock(&test_fw_mutex);
666
667 test_fw_config->reqs =
668 vzalloc(array3_size(sizeof(struct test_batched_req),
669 test_fw_config->num_requests, 2));
670 if (!test_fw_config->reqs) {
671 rc = -ENOMEM;
672 goto out_unlock;
673 }
674
675 pr_info("batched sync firmware loading '%s' %u times\n",
676 test_fw_config->name, test_fw_config->num_requests);
677
678 for (i = 0; i < test_fw_config->num_requests; i++) {
679 req = &test_fw_config->reqs[i];
680 req->fw = NULL;
681 req->idx = i;
682 req->name = test_fw_config->name;
683 req->dev = dev;
684 init_completion(&req->completion);
685 req->task = kthread_run(test_fw_run_batch_request, req,
686 "%s-%u", KBUILD_MODNAME, req->idx);
687 if (!req->task || IS_ERR(req->task)) {
688 pr_err("Setting up thread %u failed\n", req->idx);
689 req->task = NULL;
690 rc = -ENOMEM;
691 goto out_bail;
692 }
693 }
694
695 rc = count;
696
697 /*
698 * We require an explicit release to enable more time and delay of
699 * calling release_firmware() to improve our chances of forcing a
700 * batched request. If we instead called release_firmware() right away
701 * then we might miss on an opportunity of having a successful firmware
702 * request pass on the opportunity to be come a batched request.
703 */
704
705 out_bail:
706 for (i = 0; i < test_fw_config->num_requests; i++) {
707 req = &test_fw_config->reqs[i];
708 if (req->task || req->sent)
709 wait_for_completion(&req->completion);
710 }
711
712 /* Override any worker error if we had a general setup error */
713 if (rc < 0)
714 test_fw_config->test_result = rc;
715
716 out_unlock:
717 mutex_unlock(&test_fw_mutex);
718
719 return rc;
720 }
721 static DEVICE_ATTR_WO(trigger_batched_requests);
722
723 /*
724 * We wait for each callback to return with the lock held, no need to lock here
725 */
trigger_batched_cb(const struct firmware * fw,void * context)726 static void trigger_batched_cb(const struct firmware *fw, void *context)
727 {
728 struct test_batched_req *req = context;
729
730 if (!req) {
731 test_fw_config->test_result = -EINVAL;
732 return;
733 }
734
735 /* forces *some* batched requests to queue up */
736 if (!req->idx)
737 ssleep(2);
738
739 req->fw = fw;
740
741 /*
742 * Unfortunately the firmware API gives us nothing other than a null FW
743 * if the firmware was not found on async requests. Best we can do is
744 * just assume -ENOENT. A better API would pass the actual return
745 * value to the callback.
746 */
747 if (!fw && !test_fw_config->test_result)
748 test_fw_config->test_result = -ENOENT;
749
750 complete(&req->completion);
751 }
752
753 static
trigger_batched_requests_async_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)754 ssize_t trigger_batched_requests_async_store(struct device *dev,
755 struct device_attribute *attr,
756 const char *buf, size_t count)
757 {
758 struct test_batched_req *req;
759 bool send_uevent;
760 int rc;
761 u8 i;
762
763 mutex_lock(&test_fw_mutex);
764
765 test_fw_config->reqs =
766 vzalloc(array3_size(sizeof(struct test_batched_req),
767 test_fw_config->num_requests, 2));
768 if (!test_fw_config->reqs) {
769 rc = -ENOMEM;
770 goto out;
771 }
772
773 pr_info("batched loading '%s' custom fallback mechanism %u times\n",
774 test_fw_config->name, test_fw_config->num_requests);
775
776 send_uevent = test_fw_config->send_uevent ? FW_ACTION_HOTPLUG :
777 FW_ACTION_NOHOTPLUG;
778
779 for (i = 0; i < test_fw_config->num_requests; i++) {
780 req = &test_fw_config->reqs[i];
781 req->name = test_fw_config->name;
782 req->fw = NULL;
783 req->idx = i;
784 init_completion(&req->completion);
785 rc = request_firmware_nowait(THIS_MODULE, send_uevent,
786 req->name,
787 dev, GFP_KERNEL, req,
788 trigger_batched_cb);
789 if (rc) {
790 pr_info("#%u: batched async load failed setup: %d\n",
791 i, rc);
792 req->rc = rc;
793 goto out_bail;
794 } else
795 req->sent = true;
796 }
797
798 rc = count;
799
800 out_bail:
801
802 /*
803 * We require an explicit release to enable more time and delay of
804 * calling release_firmware() to improve our chances of forcing a
805 * batched request. If we instead called release_firmware() right away
806 * then we might miss on an opportunity of having a successful firmware
807 * request pass on the opportunity to be come a batched request.
808 */
809
810 for (i = 0; i < test_fw_config->num_requests; i++) {
811 req = &test_fw_config->reqs[i];
812 if (req->sent)
813 wait_for_completion(&req->completion);
814 }
815
816 /* Override any worker error if we had a general setup error */
817 if (rc < 0)
818 test_fw_config->test_result = rc;
819
820 out:
821 mutex_unlock(&test_fw_mutex);
822
823 return rc;
824 }
825 static DEVICE_ATTR_WO(trigger_batched_requests_async);
826
test_result_show(struct device * dev,struct device_attribute * attr,char * buf)827 static ssize_t test_result_show(struct device *dev,
828 struct device_attribute *attr,
829 char *buf)
830 {
831 return test_dev_config_show_int(buf, test_fw_config->test_result);
832 }
833 static DEVICE_ATTR_RO(test_result);
834
release_all_firmware_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)835 static ssize_t release_all_firmware_store(struct device *dev,
836 struct device_attribute *attr,
837 const char *buf, size_t count)
838 {
839 test_release_all_firmware();
840 return count;
841 }
842 static DEVICE_ATTR_WO(release_all_firmware);
843
read_firmware_show(struct device * dev,struct device_attribute * attr,char * buf)844 static ssize_t read_firmware_show(struct device *dev,
845 struct device_attribute *attr,
846 char *buf)
847 {
848 struct test_batched_req *req;
849 u8 idx;
850 ssize_t rc = 0;
851
852 mutex_lock(&test_fw_mutex);
853
854 idx = test_fw_config->read_fw_idx;
855 if (idx >= test_fw_config->num_requests) {
856 rc = -ERANGE;
857 goto out;
858 }
859
860 if (!test_fw_config->reqs) {
861 rc = -EINVAL;
862 goto out;
863 }
864
865 req = &test_fw_config->reqs[idx];
866 if (!req->fw) {
867 pr_err("#%u: failed to async load firmware\n", idx);
868 rc = -ENOENT;
869 goto out;
870 }
871
872 pr_info("#%u: loaded %zu\n", idx, req->fw->size);
873
874 if (req->fw->size > PAGE_SIZE) {
875 pr_err("Testing interface must use PAGE_SIZE firmware for now\n");
876 rc = -EINVAL;
877 goto out;
878 }
879 memcpy(buf, req->fw->data, req->fw->size);
880
881 rc = req->fw->size;
882 out:
883 mutex_unlock(&test_fw_mutex);
884
885 return rc;
886 }
887 static DEVICE_ATTR_RO(read_firmware);
888
889 #define TEST_FW_DEV_ATTR(name) &dev_attr_##name.attr
890
891 static struct attribute *test_dev_attrs[] = {
892 TEST_FW_DEV_ATTR(reset),
893
894 TEST_FW_DEV_ATTR(config),
895 TEST_FW_DEV_ATTR(config_name),
896 TEST_FW_DEV_ATTR(config_num_requests),
897 TEST_FW_DEV_ATTR(config_into_buf),
898 TEST_FW_DEV_ATTR(config_sync_direct),
899 TEST_FW_DEV_ATTR(config_send_uevent),
900 TEST_FW_DEV_ATTR(config_read_fw_idx),
901
902 /* These don't use the config at all - they could be ported! */
903 TEST_FW_DEV_ATTR(trigger_request),
904 TEST_FW_DEV_ATTR(trigger_async_request),
905 TEST_FW_DEV_ATTR(trigger_custom_fallback),
906
907 /* These use the config and can use the test_result */
908 TEST_FW_DEV_ATTR(trigger_batched_requests),
909 TEST_FW_DEV_ATTR(trigger_batched_requests_async),
910
911 TEST_FW_DEV_ATTR(release_all_firmware),
912 TEST_FW_DEV_ATTR(test_result),
913 TEST_FW_DEV_ATTR(read_firmware),
914 NULL,
915 };
916
917 ATTRIBUTE_GROUPS(test_dev);
918
919 static struct miscdevice test_fw_misc_device = {
920 .minor = MISC_DYNAMIC_MINOR,
921 .name = "test_firmware",
922 .fops = &test_fw_fops,
923 .groups = test_dev_groups,
924 };
925
test_firmware_init(void)926 static int __init test_firmware_init(void)
927 {
928 int rc;
929
930 test_fw_config = kzalloc(sizeof(struct test_config), GFP_KERNEL);
931 if (!test_fw_config)
932 return -ENOMEM;
933
934 rc = __test_firmware_config_init();
935 if (rc) {
936 kfree(test_fw_config);
937 pr_err("could not init firmware test config: %d\n", rc);
938 return rc;
939 }
940
941 rc = misc_register(&test_fw_misc_device);
942 if (rc) {
943 kfree(test_fw_config);
944 pr_err("could not register misc device: %d\n", rc);
945 return rc;
946 }
947
948 pr_warn("interface ready\n");
949
950 return 0;
951 }
952
953 module_init(test_firmware_init);
954
test_firmware_exit(void)955 static void __exit test_firmware_exit(void)
956 {
957 mutex_lock(&test_fw_mutex);
958 release_firmware(test_firmware);
959 misc_deregister(&test_fw_misc_device);
960 __test_firmware_config_free();
961 kfree(test_fw_config);
962 mutex_unlock(&test_fw_mutex);
963
964 pr_warn("removed interface\n");
965 }
966
967 module_exit(test_firmware_exit);
968
969 MODULE_AUTHOR("Kees Cook <keescook@chromium.org>");
970 MODULE_LICENSE("GPL");
971