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 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(config_name, 0644, config_name_show, config_name_store);
 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                 goto out;
 375         }
 376         mutex_unlock(&test_fw_mutex);
 377
 378         rc = test_dev_config_update_u8(buf, count,
 379                                        &test_fw_config->num_requests);
 380
 381 out:
 382         return rc;
 383 }
 384
 385 static ssize_t config_num_requests_show(struct device *dev,
 386                                         struct device_attribute *attr,
 387                                         char *buf)
 388 {
 389         return test_dev_config_show_u8(buf, test_fw_config->num_requests);
 390 }
 391 static DEVICE_ATTR(config_num_requests, 0644, config_num_requests_show,
 392                    config_num_requests_store);
 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(config_sync_direct, 0644, config_sync_direct_show,
 415                    config_sync_direct_store);
 416
 417 static ssize_t config_send_uevent_store(struct device *dev,
 418                                         struct device_attribute *attr,
 419                                         const char *buf, size_t count)
 420 {
 421         return test_dev_config_update_bool(buf, count,
 422                                            &test_fw_config->send_uevent);
 423 }
 424
 425 static ssize_t config_send_uevent_show(struct device *dev,
 426                                        struct device_attribute *attr,
 427                                        char *buf)
 428 {
 429         return test_dev_config_show_bool(buf, test_fw_config->send_uevent);
 430 }
 431 static DEVICE_ATTR(config_send_uevent, 0644, config_send_uevent_show,
 432                    config_send_uevent_store);
 433
 434 static ssize_t config_read_fw_idx_store(struct device *dev,
 435                                         struct device_attribute *attr,
 436                                         const char *buf, size_t count)
 437 {
 438         return test_dev_config_update_u8(buf, count,
 439                                          &test_fw_config->read_fw_idx);
 440 }
 441
 442 static ssize_t config_read_fw_idx_show(struct device *dev,
 443                                        struct device_attribute *attr,
 444                                        char *buf)
 445 {
 446         return test_dev_config_show_u8(buf, test_fw_config->read_fw_idx);
 447 }
 448 static DEVICE_ATTR(config_read_fw_idx, 0644, config_read_fw_idx_show,
 449                    config_read_fw_idx_store);
 450
 451
 452 static ssize_t trigger_request_store(struct device *dev,
 453                                      struct device_attribute *attr,
 454                                      const char *buf, size_t count)
 455 {
 456         int rc;
 457         char *name;
 458
 459         name = kstrndup(buf, count, GFP_KERNEL);
 460         if (!name)
 461                 return -ENOSPC;
 462
 463         pr_info("loading '%s'\n", name);
 464
 465         mutex_lock(&test_fw_mutex);
 466         release_firmware(test_firmware);
 467         test_firmware = NULL;
 468         rc = request_firmware(&test_firmware, name, dev);
 469         if (rc) {
 470                 pr_info("load of '%s' failed: %d\n", name, rc);
 471                 goto out;
 472         }
 473         pr_info("loaded: %zu\n", test_firmware->size);
 474         rc = count;
 475
 476 out:
 477         mutex_unlock(&test_fw_mutex);
 478
 479         kfree(name);
 480
 481         return rc;
 482 }
 483 static DEVICE_ATTR_WO(trigger_request);
 484
 485 static DECLARE_COMPLETION(async_fw_done);
 486
 487 static void trigger_async_request_cb(const struct firmware *fw, void *context)
 488 {
 489         test_firmware = fw;
 490         complete(&async_fw_done);
 491 }
 492
 493 static ssize_t trigger_async_request_store(struct device *dev,
 494                                            struct device_attribute *attr,
 495                                            const char *buf, size_t count)
 496 {
 497         int rc;
 498         char *name;
 499
 500         name = kstrndup(buf, count, GFP_KERNEL);
 501         if (!name)
 502                 return -ENOSPC;
 503
 504         pr_info("loading '%s'\n", name);
 505
 506         mutex_lock(&test_fw_mutex);
 507         release_firmware(test_firmware);
 508         test_firmware = NULL;
 509         rc = request_firmware_nowait(THIS_MODULE, 1, name, dev, GFP_KERNEL,
 510                                      NULL, trigger_async_request_cb);
 511         if (rc) {
 512                 pr_info("async load of '%s' failed: %d\n", name, rc);
 513                 kfree(name);
 514                 goto out;
 515         }
 516         /* Free 'name' ASAP, to test for race conditions */
 517         kfree(name);
 518
 519         wait_for_completion(&async_fw_done);
 520
 521         if (test_firmware) {
 522                 pr_info("loaded: %zu\n", test_firmware->size);
 523                 rc = count;
 524         } else {
 525                 pr_err("failed to async load firmware\n");
 526                 rc = -ENODEV;
 527         }
 528
 529 out:
 530         mutex_unlock(&test_fw_mutex);
 531
 532         return rc;
 533 }
 534 static DEVICE_ATTR_WO(trigger_async_request);
 535
 536 static ssize_t trigger_custom_fallback_store(struct device *dev,
 537                                              struct device_attribute *attr,
 538                                              const char *buf, size_t count)
 539 {
 540         int rc;
 541         char *name;
 542
 543         name = kstrndup(buf, count, GFP_KERNEL);
 544         if (!name)
 545                 return -ENOSPC;
 546
 547         pr_info("loading '%s' using custom fallback mechanism\n", name);
 548
 549         mutex_lock(&test_fw_mutex);
 550         release_firmware(test_firmware);
 551         test_firmware = NULL;
 552         rc = request_firmware_nowait(THIS_MODULE, FW_ACTION_NOHOTPLUG, name,
 553                                      dev, GFP_KERNEL, NULL,
 554                                      trigger_async_request_cb);
 555         if (rc) {
 556                 pr_info("async load of '%s' failed: %d\n", name, rc);
 557                 kfree(name);
 558                 goto out;
 559         }
 560         /* Free 'name' ASAP, to test for race conditions */
 561         kfree(name);
 562
 563         wait_for_completion(&async_fw_done);
 564
 565         if (test_firmware) {
 566                 pr_info("loaded: %zu\n", test_firmware->size);
 567                 rc = count;
 568         } else {
 569                 pr_err("failed to async load firmware\n");
 570                 rc = -ENODEV;
 571         }
 572
 573 out:
 574         mutex_unlock(&test_fw_mutex);
 575
 576         return rc;
 577 }
 578 static DEVICE_ATTR_WO(trigger_custom_fallback);
 579
 580 static int test_fw_run_batch_request(void *data)
 581 {
 582         struct test_batched_req *req = data;
 583
 584         if (!req) {
 585                 test_fw_config->test_result = -EINVAL;
 586                 return -EINVAL;
 587         }
 588
 589         req->rc = test_fw_config->req_firmware(&req->fw, req->name, req->dev);
 590         if (req->rc) {
 591                 pr_info("#%u: batched sync load failed: %d\n",
 592                         req->idx, req->rc);
 593                 if (!test_fw_config->test_result)
 594                         test_fw_config->test_result = req->rc;
 595         } else if (req->fw) {
 596                 req->sent = true;
 597                 pr_info("#%u: batched sync loaded %zu\n",
 598                         req->idx, req->fw->size);
 599         }
 600         complete(&req->completion);
 601
 602         req->task = NULL;
 603
 604         return 0;
 605 }
 606
 607 /*
 608  * We use a kthread as otherwise the kernel serializes all our sync requests
 609  * and we would not be able to mimic batched requests on a sync call. Batched
 610  * requests on a sync call can for instance happen on a device driver when
 611  * multiple cards are used and firmware loading happens outside of probe.
 612  */
 613 static ssize_t trigger_batched_requests_store(struct device *dev,
 614                                               struct device_attribute *attr,
 615                                               const char *buf, size_t count)
 616 {
 617         struct test_batched_req *req;
 618         int rc;
 619         u8 i;
 620
 621         mutex_lock(&test_fw_mutex);
 622
 623         test_fw_config->reqs = vzalloc(sizeof(struct test_batched_req) *
 624                                        test_fw_config->num_requests * 2);
 625         if (!test_fw_config->reqs) {
 626                 rc = -ENOMEM;
 627                 goto out_unlock;
 628         }
 629
 630         pr_info("batched sync firmware loading '%s' %u times\n",
 631                 test_fw_config->name, test_fw_config->num_requests);
 632
 633         for (i = 0; i < test_fw_config->num_requests; i++) {
 634                 req = &test_fw_config->reqs[i];
 635                 if (!req) {
 636                         WARN_ON(1);
 637                         rc = -ENOMEM;
 638                         goto out_bail;
 639                 }
 640                 req->fw = NULL;
 641                 req->idx = i;
 642                 req->name = test_fw_config->name;
 643                 req->dev = dev;
 644                 init_completion(&req->completion);
 645                 req->task = kthread_run(test_fw_run_batch_request, req,
 646                                              "%s-%u", KBUILD_MODNAME, req->idx);
 647                 if (!req->task || IS_ERR(req->task)) {
 648                         pr_err("Setting up thread %u failed\n", req->idx);
 649                         req->task = NULL;
 650                         rc = -ENOMEM;
 651                         goto out_bail;
 652                 }
 653         }
 654
 655         rc = count;
 656
 657         /*
 658          * We require an explicit release to enable more time and delay of
 659          * calling release_firmware() to improve our chances of forcing a
 660          * batched request. If we instead called release_firmware() right away
 661          * then we might miss on an opportunity of having a successful firmware
 662          * request pass on the opportunity to be come a batched request.
 663          */
 664
 665 out_bail:
 666         for (i = 0; i < test_fw_config->num_requests; i++) {
 667                 req = &test_fw_config->reqs[i];
 668                 if (req->task || req->sent)
 669                         wait_for_completion(&req->completion);
 670         }
 671
 672         /* Override any worker error if we had a general setup error */
 673         if (rc < 0)
 674                 test_fw_config->test_result = rc;
 675
 676 out_unlock:
 677         mutex_unlock(&test_fw_mutex);
 678
 679         return rc;
 680 }
 681 static DEVICE_ATTR_WO(trigger_batched_requests);
 682
 683 /*
 684  * We wait for each callback to return with the lock held, no need to lock here
 685  */
 686 static void trigger_batched_cb(const struct firmware *fw, void *context)
 687 {
 688         struct test_batched_req *req = context;
 689
 690         if (!req) {
 691                 test_fw_config->test_result = -EINVAL;
 692                 return;
 693         }
 694
 695         /* forces *some* batched requests to queue up */
 696         if (!req->idx)
 697                 ssleep(2);
 698
 699         req->fw = fw;
 700
 701         /*
 702          * Unfortunately the firmware API gives us nothing other than a null FW
 703          * if the firmware was not found on async requests.  Best we can do is
 704          * just assume -ENOENT. A better API would pass the actual return
 705          * value to the callback.
 706          */
 707         if (!fw && !test_fw_config->test_result)
 708                 test_fw_config->test_result = -ENOENT;
 709
 710         complete(&req->completion);
 711 }
 712
 713 static
 714 ssize_t trigger_batched_requests_async_store(struct device *dev,
 715                                              struct device_attribute *attr,
 716                                              const char *buf, size_t count)
 717 {
 718         struct test_batched_req *req;
 719         bool send_uevent;
 720         int rc;
 721         u8 i;
 722
 723         mutex_lock(&test_fw_mutex);
 724
 725         test_fw_config->reqs = vzalloc(sizeof(struct test_batched_req) *
 726                                        test_fw_config->num_requests * 2);
 727         if (!test_fw_config->reqs) {
 728                 rc = -ENOMEM;
 729                 goto out;
 730         }
 731
 732         pr_info("batched loading '%s' custom fallback mechanism %u times\n",
 733                 test_fw_config->name, test_fw_config->num_requests);
 734
 735         send_uevent = test_fw_config->send_uevent ? FW_ACTION_HOTPLUG :
 736                 FW_ACTION_NOHOTPLUG;
 737
 738         for (i = 0; i < test_fw_config->num_requests; i++) {
 739                 req = &test_fw_config->reqs[i];
 740                 if (!req) {
 741                         WARN_ON(1);
 742                         goto out_bail;
 743                 }
 744                 req->name = test_fw_config->name;
 745                 req->fw = NULL;
 746                 req->idx = i;
 747                 init_completion(&req->completion);
 748                 rc = request_firmware_nowait(THIS_MODULE, send_uevent,
 749                                              req->name,
 750                                              dev, GFP_KERNEL, req,
 751                                              trigger_batched_cb);
 752                 if (rc) {
 753                         pr_info("#%u: batched async load failed setup: %d\n",
 754                                 i, rc);
 755                         req->rc = rc;
 756                         goto out_bail;
 757                 } else
 758                         req->sent = true;
 759         }
 760
 761         rc = count;
 762
 763 out_bail:
 764
 765         /*
 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.
 771          */
 772
 773         for (i = 0; i < test_fw_config->num_requests; i++) {
 774                 req = &test_fw_config->reqs[i];
 775                 if (req->sent)
 776                         wait_for_completion(&req->completion);
 777         }
 778
 779         /* Override any worker error if we had a general setup error */
 780         if (rc < 0)
 781                 test_fw_config->test_result = rc;
 782
 783 out:
 784         mutex_unlock(&test_fw_mutex);
 785
 786         return rc;
 787 }
 788 static DEVICE_ATTR_WO(trigger_batched_requests_async);
 789
 790 static ssize_t test_result_show(struct device *dev,
 791                                 struct device_attribute *attr,
 792                                 char *buf)
 793 {
 794         return test_dev_config_show_int(buf, test_fw_config->test_result);
 795 }
 796 static DEVICE_ATTR_RO(test_result);
 797
 798 static ssize_t release_all_firmware_store(struct device *dev,
 799                                           struct device_attribute *attr,
 800                                           const char *buf, size_t count)
 801 {
 802         test_release_all_firmware();
 803         return count;
 804 }
 805 static DEVICE_ATTR_WO(release_all_firmware);
 806
 807 static ssize_t read_firmware_show(struct device *dev,
 808                                   struct device_attribute *attr,
 809                                   char *buf)
 810 {
 811         struct test_batched_req *req;
 812         u8 idx;
 813         ssize_t rc = 0;
 814
 815         mutex_lock(&test_fw_mutex);
 816
 817         idx = test_fw_config->read_fw_idx;
 818         if (idx >= test_fw_config->num_requests) {
 819                 rc = -ERANGE;
 820                 goto out;
 821         }
 822
 823         if (!test_fw_config->reqs) {
 824                 rc = -EINVAL;
 825                 goto out;
 826         }
 827
 828         req = &test_fw_config->reqs[idx];
 829         if (!req->fw) {
 830                 pr_err("#%u: failed to async load firmware\n", idx);
 831                 rc = -ENOENT;
 832                 goto out;
 833         }
 834
 835         pr_info("#%u: loaded %zu\n", idx, req->fw->size);
 836
 837         if (req->fw->size > PAGE_SIZE) {
 838                 pr_err("Testing interface must use PAGE_SIZE firmware for now\n");
 839                 rc = -EINVAL;
 840         }
 841         memcpy(buf, req->fw->data, req->fw->size);
 842
 843         rc = req->fw->size;
 844 out:
 845         mutex_unlock(&test_fw_mutex);
 846
 847         return rc;
 848 }
 849 static DEVICE_ATTR_RO(read_firmware);
 850
 851 #define TEST_FW_DEV_ATTR(name)          &dev_attr_##name.attr
 852
 853 static struct attribute *test_dev_attrs[] = {
 854         TEST_FW_DEV_ATTR(reset),
 855
 856         TEST_FW_DEV_ATTR(config),
 857         TEST_FW_DEV_ATTR(config_name),
 858         TEST_FW_DEV_ATTR(config_num_requests),
 859         TEST_FW_DEV_ATTR(config_sync_direct),
 860         TEST_FW_DEV_ATTR(config_send_uevent),
 861         TEST_FW_DEV_ATTR(config_read_fw_idx),
 862
 863         /* These don't use the config at all - they could be ported! */
 864         TEST_FW_DEV_ATTR(trigger_request),
 865         TEST_FW_DEV_ATTR(trigger_async_request),
 866         TEST_FW_DEV_ATTR(trigger_custom_fallback),
 867
 868         /* These use the config and can use the test_result */
 869         TEST_FW_DEV_ATTR(trigger_batched_requests),
 870         TEST_FW_DEV_ATTR(trigger_batched_requests_async),
 871
 872         TEST_FW_DEV_ATTR(release_all_firmware),
 873         TEST_FW_DEV_ATTR(test_result),
 874         TEST_FW_DEV_ATTR(read_firmware),
 875         NULL,
 876 };
 877
 878 ATTRIBUTE_GROUPS(test_dev);
 879
 880 static struct miscdevice test_fw_misc_device = {
 881         .minor          = MISC_DYNAMIC_MINOR,
 882         .name           = "test_firmware",
 883         .fops           = &test_fw_fops,
 884         .groups         = test_dev_groups,
 885 };
 886
 887 static int __init test_firmware_init(void)
 888 {
 889         int rc;
 890
 891         test_fw_config = kzalloc(sizeof(struct test_config), GFP_KERNEL);
 892         if (!test_fw_config)
 893                 return -ENOMEM;
 894
 895         rc = __test_firmware_config_init();
 896         if (rc)
 897                 return rc;
 898
 899         rc = misc_register(&test_fw_misc_device);
 900         if (rc) {
 901                 kfree(test_fw_config);
 902                 pr_err("could not register misc device: %d\n", rc);
 903                 return rc;
 904         }
 905
 906         pr_warn("interface ready\n");
 907
 908         return 0;
 909 }
 910
 911 module_init(test_firmware_init);
 912
 913 static void __exit test_firmware_exit(void)
 914 {
 915         mutex_lock(&test_fw_mutex);
 916         release_firmware(test_firmware);
 917         misc_deregister(&test_fw_misc_device);
 918         __test_firmware_config_free();
 919         kfree(test_fw_config);
 920         mutex_unlock(&test_fw_mutex);
 921
 922         pr_warn("removed interface\n");
 923 }
 924
 925 module_exit(test_firmware_exit);
 926
 927 MODULE_AUTHOR("Kees Cook <keescook@chromium.org>");
 928 MODULE_LICENSE("GPL");