lib/test_firmware.c

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