drivers/base/firmware_class.c

   1 /*
   2  * firmware_class.c - Multi purpose firmware loading support
   3  *
   4  * Copyright (c) 2003 Manuel Estrada Sainz
   5  *
   6  * Please see Documentation/firmware_class/ for more information.
   7  *
   8  */
   9
  10 #include <linux/capability.h>
  11 #include <linux/device.h>
  12 #include <linux/module.h>
  13 #include <linux/init.h>
  14 #include <linux/timer.h>
  15 #include <linux/vmalloc.h>
  16 #include <linux/interrupt.h>
  17 #include <linux/bitops.h>
  18 #include <linux/mutex.h>
  19 #include <linux/workqueue.h>
  20 #include <linux/highmem.h>
  21 #include <linux/firmware.h>
  22 #include <linux/slab.h>
  23 #include <linux/sched.h>
  24 #include <linux/file.h>
  25 #include <linux/list.h>
  26 #include <linux/async.h>
  27 #include <linux/pm.h>
  28 #include <linux/suspend.h>
  29 #include <linux/syscore_ops.h>
  30 #include <linux/reboot.h>
  31
  32 #include <generated/utsrelease.h>
  33
  34 #include "base.h"
  35
  36 MODULE_AUTHOR("Manuel Estrada Sainz");
  37 MODULE_DESCRIPTION("Multi purpose firmware loading support");
  38 MODULE_LICENSE("GPL");
  39
  40 /* Builtin firmware support */
  41
  42 #ifdef CONFIG_FW_LOADER
  43
  44 extern struct builtin_fw __start_builtin_fw[];
  45 extern struct builtin_fw __end_builtin_fw[];
  46
  47 static bool fw_get_builtin_firmware(struct firmware *fw, const char *name)
  48 {
  49         struct builtin_fw *b_fw;
  50
  51         for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++) {
  52                 if (strcmp(name, b_fw->name) == 0) {
  53                         fw->size = b_fw->size;
  54                         fw->data = b_fw->data;
  55                         return true;
  56                 }
  57         }
  58
  59         return false;
  60 }
  61
  62 static bool fw_is_builtin_firmware(const struct firmware *fw)
  63 {
  64         struct builtin_fw *b_fw;
  65
  66         for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++)
  67                 if (fw->data == b_fw->data)
  68                         return true;
  69
  70         return false;
  71 }
  72
  73 #else /* Module case - no builtin firmware support */
  74
  75 static inline bool fw_get_builtin_firmware(struct firmware *fw, const char *name)
  76 {
  77         return false;
  78 }
  79
  80 static inline bool fw_is_builtin_firmware(const struct firmware *fw)
  81 {
  82         return false;
  83 }
  84 #endif
  85
  86 enum {
  87         FW_STATUS_LOADING,
  88         FW_STATUS_DONE,
  89         FW_STATUS_ABORT,
  90 };
  91
  92 static int loading_timeout = 60;        /* In seconds */
  93
  94 static inline long firmware_loading_timeout(void)
  95 {
  96         return loading_timeout > 0 ? loading_timeout * HZ : MAX_SCHEDULE_TIMEOUT;
  97 }
  98
  99 struct firmware_cache {
 100         /* firmware_buf instance will be added into the below list */
 101         spinlock_t lock;
 102         struct list_head head;
 103         int state;
 104
 105 #ifdef CONFIG_PM_SLEEP
 106         /*
 107          * Names of firmware images which have been cached successfully
 108          * will be added into the below list so that device uncache
 109          * helper can trace which firmware images have been cached
 110          * before.
 111          */
 112         spinlock_t name_lock;
 113         struct list_head fw_names;
 114
 115         struct delayed_work work;
 116
 117         struct notifier_block   pm_notify;
 118 #endif
 119 };
 120
 121 struct firmware_buf {
 122         struct kref ref;
 123         struct list_head list;
 124         struct completion completion;
 125         struct firmware_cache *fwc;
 126         unsigned long status;
 127         void *data;
 128         size_t size;
 129 #ifdef CONFIG_FW_LOADER_USER_HELPER
 130         bool is_paged_buf;
 131         bool need_uevent;
 132         struct page **pages;
 133         int nr_pages;
 134         int page_array_size;
 135         struct list_head pending_list;
 136 #endif
 137         char fw_id[];
 138 };
 139
 140 struct fw_cache_entry {
 141         struct list_head list;
 142         char name[];
 143 };
 144
 145 struct fw_name_devm {
 146         unsigned long magic;
 147         char name[];
 148 };
 149
 150 #define to_fwbuf(d) container_of(d, struct firmware_buf, ref)
 151
 152 #define FW_LOADER_NO_CACHE      0
 153 #define FW_LOADER_START_CACHE   1
 154
 155 static int fw_cache_piggyback_on_request(const char *name);
 156
 157 /* fw_lock could be moved to 'struct firmware_priv' but since it is just
 158  * guarding for corner cases a global lock should be OK */
 159 static DEFINE_MUTEX(fw_lock);
 160
 161 static struct firmware_cache fw_cache;
 162
 163 static struct firmware_buf *__allocate_fw_buf(const char *fw_name,
 164                                               struct firmware_cache *fwc)
 165 {
 166         struct firmware_buf *buf;
 167
 168         buf = kzalloc(sizeof(*buf) + strlen(fw_name) + 1 , GFP_ATOMIC);
 169
 170         if (!buf)
 171                 return buf;
 172
 173         kref_init(&buf->ref);
 174         strcpy(buf->fw_id, fw_name);
 175         buf->fwc = fwc;
 176         init_completion(&buf->completion);
 177 #ifdef CONFIG_FW_LOADER_USER_HELPER
 178         INIT_LIST_HEAD(&buf->pending_list);
 179 #endif
 180
 181         pr_debug("%s: fw-%s buf=%p\n", __func__, fw_name, buf);
 182
 183         return buf;
 184 }
 185
 186 static struct firmware_buf *__fw_lookup_buf(const char *fw_name)
 187 {
 188         struct firmware_buf *tmp;
 189         struct firmware_cache *fwc = &fw_cache;
 190
 191         list_for_each_entry(tmp, &fwc->head, list)
 192                 if (!strcmp(tmp->fw_id, fw_name))
 193                         return tmp;
 194         return NULL;
 195 }
 196
 197 static int fw_lookup_and_allocate_buf(const char *fw_name,
 198                                       struct firmware_cache *fwc,
 199                                       struct firmware_buf **buf)
 200 {
 201         struct firmware_buf *tmp;
 202
 203         spin_lock(&fwc->lock);
 204         tmp = __fw_lookup_buf(fw_name);
 205         if (tmp) {
 206                 kref_get(&tmp->ref);
 207                 spin_unlock(&fwc->lock);
 208                 *buf = tmp;
 209                 return 1;
 210         }
 211         tmp = __allocate_fw_buf(fw_name, fwc);
 212         if (tmp)
 213                 list_add(&tmp->list, &fwc->head);
 214         spin_unlock(&fwc->lock);
 215
 216         *buf = tmp;
 217
 218         return tmp ? 0 : -ENOMEM;
 219 }
 220
 221 static struct firmware_buf *fw_lookup_buf(const char *fw_name)
 222 {
 223         struct firmware_buf *tmp;
 224         struct firmware_cache *fwc = &fw_cache;
 225
 226         spin_lock(&fwc->lock);
 227         tmp = __fw_lookup_buf(fw_name);
 228         spin_unlock(&fwc->lock);
 229
 230         return tmp;
 231 }
 232
 233 static void __fw_free_buf(struct kref *ref)
 234 {
 235         struct firmware_buf *buf = to_fwbuf(ref);
 236         struct firmware_cache *fwc = buf->fwc;
 237
 238         pr_debug("%s: fw-%s buf=%p data=%p size=%u\n",
 239                  __func__, buf->fw_id, buf, buf->data,
 240                  (unsigned int)buf->size);
 241
 242         list_del(&buf->list);
 243         spin_unlock(&fwc->lock);
 244
 245 #ifdef CONFIG_FW_LOADER_USER_HELPER
 246         if (buf->is_paged_buf) {
 247                 int i;
 248                 vunmap(buf->data);
 249                 for (i = 0; i < buf->nr_pages; i++)
 250                         __free_page(buf->pages[i]);
 251                 kfree(buf->pages);
 252         } else
 253 #endif
 254                 vfree(buf->data);
 255         kfree(buf);
 256 }
 257
 258 static void fw_free_buf(struct firmware_buf *buf)
 259 {
 260         struct firmware_cache *fwc = buf->fwc;
 261         spin_lock(&fwc->lock);
 262         if (!kref_put(&buf->ref, __fw_free_buf))
 263                 spin_unlock(&fwc->lock);
 264 }
 265
 266 /* direct firmware loading support */
 267 static char fw_path_para[256];
 268 static const char * const fw_path[] = {
 269         fw_path_para,
 270         "/lib/firmware/updates/" UTS_RELEASE,
 271         "/lib/firmware/updates",
 272         "/lib/firmware/" UTS_RELEASE,
 273         "/lib/firmware"
 274 };
 275
 276 /*
 277  * Typical usage is that passing 'firmware_class.path=$CUSTOMIZED_PATH'
 278  * from kernel command line because firmware_class is generally built in
 279  * kernel instead of module.
 280  */
 281 module_param_string(path, fw_path_para, sizeof(fw_path_para), 0644);
 282 MODULE_PARM_DESC(path, "customized firmware image search path with a higher priority than default path");
 283
 284 /* Don't inline this: 'struct kstat' is biggish */
 285 static noinline_for_stack long fw_file_size(struct file *file)
 286 {
 287         struct kstat st;
 288         if (vfs_getattr(&file->f_path, &st))
 289                 return -1;
 290         if (!S_ISREG(st.mode))
 291                 return -1;
 292         if (st.size != (long)st.size)
 293                 return -1;
 294         return st.size;
 295 }
 296
 297 static bool fw_read_file_contents(struct file *file, struct firmware_buf *fw_buf)
 298 {
 299         long size;
 300         char *buf;
 301
 302         size = fw_file_size(file);
 303         if (size <= 0)
 304                 return false;
 305         buf = vmalloc(size);
 306         if (!buf)
 307                 return false;
 308         if (kernel_read(file, 0, buf, size) != size) {
 309                 vfree(buf);
 310                 return false;
 311         }
 312         fw_buf->data = buf;
 313         fw_buf->size = size;
 314         return true;
 315 }
 316
 317 static bool fw_get_filesystem_firmware(struct device *device,
 318                                        struct firmware_buf *buf)
 319 {
 320         int i;
 321         bool success = false;
 322         char *path = __getname();
 323
 324         for (i = 0; i < ARRAY_SIZE(fw_path); i++) {
 325                 struct file *file;
 326
 327                 /* skip the unset customized path */
 328                 if (!fw_path[i][0])
 329                         continue;
 330
 331                 snprintf(path, PATH_MAX, "%s/%s", fw_path[i], buf->fw_id);
 332
 333                 file = filp_open(path, O_RDONLY, 0);
 334                 if (IS_ERR(file))
 335                         continue;
 336                 success = fw_read_file_contents(file, buf);
 337                 fput(file);
 338                 if (success)
 339                         break;
 340         }
 341         __putname(path);
 342
 343         if (success) {
 344                 dev_dbg(device, "firmware: direct-loading firmware %s\n",
 345                         buf->fw_id);
 346                 mutex_lock(&fw_lock);
 347                 set_bit(FW_STATUS_DONE, &buf->status);
 348                 complete_all(&buf->completion);
 349                 mutex_unlock(&fw_lock);
 350         }
 351
 352         return success;
 353 }
 354
 355 /* firmware holds the ownership of pages */
 356 static void firmware_free_data(const struct firmware *fw)
 357 {
 358         /* Loaded directly? */
 359         if (!fw->priv) {
 360                 vfree(fw->data);
 361                 return;
 362         }
 363         fw_free_buf(fw->priv);
 364 }
 365
 366 /* store the pages buffer info firmware from buf */
 367 static void fw_set_page_data(struct firmware_buf *buf, struct firmware *fw)
 368 {
 369         fw->priv = buf;
 370 #ifdef CONFIG_FW_LOADER_USER_HELPER
 371         fw->pages = buf->pages;
 372 #endif
 373         fw->size = buf->size;
 374         fw->data = buf->data;
 375
 376         pr_debug("%s: fw-%s buf=%p data=%p size=%u\n",
 377                  __func__, buf->fw_id, buf, buf->data,
 378                  (unsigned int)buf->size);
 379 }
 380
 381 #ifdef CONFIG_PM_SLEEP
 382 static void fw_name_devm_release(struct device *dev, void *res)
 383 {
 384         struct fw_name_devm *fwn = res;
 385
 386         if (fwn->magic == (unsigned long)&fw_cache)
 387                 pr_debug("%s: fw_name-%s devm-%p released\n",
 388                                 __func__, fwn->name, res);
 389 }
 390
 391 static int fw_devm_match(struct device *dev, void *res,
 392                 void *match_data)
 393 {
 394         struct fw_name_devm *fwn = res;
 395
 396         return (fwn->magic == (unsigned long)&fw_cache) &&
 397                 !strcmp(fwn->name, match_data);
 398 }
 399
 400 static struct fw_name_devm *fw_find_devm_name(struct device *dev,
 401                 const char *name)
 402 {
 403         struct fw_name_devm *fwn;
 404
 405         fwn = devres_find(dev, fw_name_devm_release,
 406                           fw_devm_match, (void *)name);
 407         return fwn;
 408 }
 409
 410 /* add firmware name into devres list */
 411 static int fw_add_devm_name(struct device *dev, const char *name)
 412 {
 413         struct fw_name_devm *fwn;
 414
 415         fwn = fw_find_devm_name(dev, name);
 416         if (fwn)
 417                 return 1;
 418
 419         fwn = devres_alloc(fw_name_devm_release, sizeof(struct fw_name_devm) +
 420                            strlen(name) + 1, GFP_KERNEL);
 421         if (!fwn)
 422                 return -ENOMEM;
 423
 424         fwn->magic = (unsigned long)&fw_cache;
 425         strcpy(fwn->name, name);
 426         devres_add(dev, fwn);
 427
 428         return 0;
 429 }
 430 #else
 431 static int fw_add_devm_name(struct device *dev, const char *name)
 432 {
 433         return 0;
 434 }
 435 #endif
 436
 437
 438 /*
 439  * user-mode helper code
 440  */
 441 #ifdef CONFIG_FW_LOADER_USER_HELPER
 442 struct firmware_priv {
 443         struct delayed_work timeout_work;
 444         bool nowait;
 445         struct device dev;
 446         struct firmware_buf *buf;
 447         struct firmware *fw;
 448 };
 449
 450 static struct firmware_priv *to_firmware_priv(struct device *dev)
 451 {
 452         return container_of(dev, struct firmware_priv, dev);
 453 }
 454
 455 static void __fw_load_abort(struct firmware_buf *buf)
 456 {
 457         /*
 458          * There is a small window in which user can write to 'loading'
 459          * between loading done and disappearance of 'loading'
 460          */
 461         if (test_bit(FW_STATUS_DONE, &buf->status))
 462                 return;
 463
 464         list_del_init(&buf->pending_list);
 465         set_bit(FW_STATUS_ABORT, &buf->status);
 466         complete_all(&buf->completion);
 467 }
 468
 469 static void fw_load_abort(struct firmware_priv *fw_priv)
 470 {
 471         struct firmware_buf *buf = fw_priv->buf;
 472
 473         __fw_load_abort(buf);
 474
 475         /* avoid user action after loading abort */
 476         fw_priv->buf = NULL;
 477 }
 478
 479 #define is_fw_load_aborted(buf) \
 480         test_bit(FW_STATUS_ABORT, &(buf)->status)
 481
 482 static LIST_HEAD(pending_fw_head);
 483
 484 /* reboot notifier for avoid deadlock with usermode_lock */
 485 static int fw_shutdown_notify(struct notifier_block *unused1,
 486                               unsigned long unused2, void *unused3)
 487 {
 488         mutex_lock(&fw_lock);
 489         while (!list_empty(&pending_fw_head))
 490                 __fw_load_abort(list_first_entry(&pending_fw_head,
 491                                                struct firmware_buf,
 492                                                pending_list));
 493         mutex_unlock(&fw_lock);
 494         return NOTIFY_DONE;
 495 }
 496
 497 static struct notifier_block fw_shutdown_nb = {
 498         .notifier_call = fw_shutdown_notify,
 499 };
 500
 501 static ssize_t firmware_timeout_show(struct class *class,
 502                                      struct class_attribute *attr,
 503                                      char *buf)
 504 {
 505         return sprintf(buf, "%d\n", loading_timeout);
 506 }
 507
 508 /**
 509  * firmware_timeout_store - set number of seconds to wait for firmware
 510  * @class: device class pointer
 511  * @attr: device attribute pointer
 512  * @buf: buffer to scan for timeout value
 513  * @count: number of bytes in @buf
 514  *
 515  *      Sets the number of seconds to wait for the firmware.  Once
 516  *      this expires an error will be returned to the driver and no
 517  *      firmware will be provided.
 518  *
 519  *      Note: zero means 'wait forever'.
 520  **/
 521 static ssize_t firmware_timeout_store(struct class *class,
 522                                       struct class_attribute *attr,
 523                                       const char *buf, size_t count)
 524 {
 525         loading_timeout = simple_strtol(buf, NULL, 10);
 526         if (loading_timeout < 0)
 527                 loading_timeout = 0;
 528
 529         return count;
 530 }
 531
 532 static struct class_attribute firmware_class_attrs[] = {
 533         __ATTR(timeout, S_IWUSR | S_IRUGO,
 534                 firmware_timeout_show, firmware_timeout_store),
 535         __ATTR_NULL
 536 };
 537
 538 static void fw_dev_release(struct device *dev)
 539 {
 540         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 541
 542         kfree(fw_priv);
 543 }
 544
 545 static int firmware_uevent(struct device *dev, struct kobj_uevent_env *env)
 546 {
 547         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 548
 549         if (add_uevent_var(env, "FIRMWARE=%s", fw_priv->buf->fw_id))
 550                 return -ENOMEM;
 551         if (add_uevent_var(env, "TIMEOUT=%i", loading_timeout))
 552                 return -ENOMEM;
 553         if (add_uevent_var(env, "ASYNC=%d", fw_priv->nowait))
 554                 return -ENOMEM;
 555
 556         return 0;
 557 }
 558
 559 static struct class firmware_class = {
 560         .name           = "firmware",
 561         .class_attrs    = firmware_class_attrs,
 562         .dev_uevent     = firmware_uevent,
 563         .dev_release    = fw_dev_release,
 564 };
 565
 566 static ssize_t firmware_loading_show(struct device *dev,
 567                                      struct device_attribute *attr, char *buf)
 568 {
 569         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 570         int loading = 0;
 571
 572         mutex_lock(&fw_lock);
 573         if (fw_priv->buf)
 574                 loading = test_bit(FW_STATUS_LOADING, &fw_priv->buf->status);
 575         mutex_unlock(&fw_lock);
 576
 577         return sprintf(buf, "%d\n", loading);
 578 }
 579
 580 /* Some architectures don't have PAGE_KERNEL_RO */
 581 #ifndef PAGE_KERNEL_RO
 582 #define PAGE_KERNEL_RO PAGE_KERNEL
 583 #endif
 584
 585 /* one pages buffer should be mapped/unmapped only once */
 586 static int fw_map_pages_buf(struct firmware_buf *buf)
 587 {
 588         if (!buf->is_paged_buf)
 589                 return 0;
 590
 591         if (buf->data)
 592                 vunmap(buf->data);
 593         buf->data = vmap(buf->pages, buf->nr_pages, 0, PAGE_KERNEL_RO);
 594         if (!buf->data)
 595                 return -ENOMEM;
 596         return 0;
 597 }
 598
 599 /**
 600  * firmware_loading_store - set value in the 'loading' control file
 601  * @dev: device pointer
 602  * @attr: device attribute pointer
 603  * @buf: buffer to scan for loading control value
 604  * @count: number of bytes in @buf
 605  *
 606  *      The relevant values are:
 607  *
 608  *       1: Start a load, discarding any previous partial load.
 609  *       0: Conclude the load and hand the data to the driver code.
 610  *      -1: Conclude the load with an error and discard any written data.
 611  **/
 612 static ssize_t firmware_loading_store(struct device *dev,
 613                                       struct device_attribute *attr,
 614                                       const char *buf, size_t count)
 615 {
 616         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 617         struct firmware_buf *fw_buf;
 618         int loading = simple_strtol(buf, NULL, 10);
 619         int i;
 620
 621         mutex_lock(&fw_lock);
 622         fw_buf = fw_priv->buf;
 623         if (!fw_buf)
 624                 goto out;
 625
 626         switch (loading) {
 627         case 1:
 628                 /* discarding any previous partial load */
 629                 if (!test_bit(FW_STATUS_DONE, &fw_buf->status)) {
 630                         for (i = 0; i < fw_buf->nr_pages; i++)
 631                                 __free_page(fw_buf->pages[i]);
 632                         kfree(fw_buf->pages);
 633                         fw_buf->pages = NULL;
 634                         fw_buf->page_array_size = 0;
 635                         fw_buf->nr_pages = 0;
 636                         set_bit(FW_STATUS_LOADING, &fw_buf->status);
 637                 }
 638                 break;
 639         case 0:
 640                 if (test_bit(FW_STATUS_LOADING, &fw_buf->status)) {
 641                         set_bit(FW_STATUS_DONE, &fw_buf->status);
 642                         clear_bit(FW_STATUS_LOADING, &fw_buf->status);
 643
 644                         /*
 645                          * Several loading requests may be pending on
 646                          * one same firmware buf, so let all requests
 647                          * see the mapped 'buf->data' once the loading
 648                          * is completed.
 649                          * */
 650                         fw_map_pages_buf(fw_buf);
 651                         list_del_init(&fw_buf->pending_list);
 652                         complete_all(&fw_buf->completion);
 653                         break;
 654                 }
 655                 /* fallthrough */
 656         default:
 657                 dev_err(dev, "%s: unexpected value (%d)\n", __func__, loading);
 658                 /* fallthrough */
 659         case -1:
 660                 fw_load_abort(fw_priv);
 661                 break;
 662         }
 663 out:
 664         mutex_unlock(&fw_lock);
 665         return count;
 666 }
 667
 668 static DEVICE_ATTR(loading, 0644, firmware_loading_show, firmware_loading_store);
 669
 670 static ssize_t firmware_data_read(struct file *filp, struct kobject *kobj,
 671                                   struct bin_attribute *bin_attr,
 672                                   char *buffer, loff_t offset, size_t count)
 673 {
 674         struct device *dev = kobj_to_dev(kobj);
 675         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 676         struct firmware_buf *buf;
 677         ssize_t ret_count;
 678
 679         mutex_lock(&fw_lock);
 680         buf = fw_priv->buf;
 681         if (!buf || test_bit(FW_STATUS_DONE, &buf->status)) {
 682                 ret_count = -ENODEV;
 683                 goto out;
 684         }
 685         if (offset > buf->size) {
 686                 ret_count = 0;
 687                 goto out;
 688         }
 689         if (count > buf->size - offset)
 690                 count = buf->size - offset;
 691
 692         ret_count = count;
 693
 694         while (count) {
 695                 void *page_data;
 696                 int page_nr = offset >> PAGE_SHIFT;
 697                 int page_ofs = offset & (PAGE_SIZE-1);
 698                 int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
 699
 700                 page_data = kmap(buf->pages[page_nr]);
 701
 702                 memcpy(buffer, page_data + page_ofs, page_cnt);
 703
 704                 kunmap(buf->pages[page_nr]);
 705                 buffer += page_cnt;
 706                 offset += page_cnt;
 707                 count -= page_cnt;
 708         }
 709 out:
 710         mutex_unlock(&fw_lock);
 711         return ret_count;
 712 }
 713
 714 static int fw_realloc_buffer(struct firmware_priv *fw_priv, int min_size)
 715 {
 716         struct firmware_buf *buf = fw_priv->buf;
 717         int pages_needed = ALIGN(min_size, PAGE_SIZE) >> PAGE_SHIFT;
 718
 719         /* If the array of pages is too small, grow it... */
 720         if (buf->page_array_size < pages_needed) {
 721                 int new_array_size = max(pages_needed,
 722                                          buf->page_array_size * 2);
 723                 struct page **new_pages;
 724
 725                 new_pages = kmalloc(new_array_size * sizeof(void *),
 726                                     GFP_KERNEL);
 727                 if (!new_pages) {
 728                         fw_load_abort(fw_priv);
 729                         return -ENOMEM;
 730                 }
 731                 memcpy(new_pages, buf->pages,
 732                        buf->page_array_size * sizeof(void *));
 733                 memset(&new_pages[buf->page_array_size], 0, sizeof(void *) *
 734                        (new_array_size - buf->page_array_size));
 735                 kfree(buf->pages);
 736                 buf->pages = new_pages;
 737                 buf->page_array_size = new_array_size;
 738         }
 739
 740         while (buf->nr_pages < pages_needed) {
 741                 buf->pages[buf->nr_pages] =
 742                         alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
 743
 744                 if (!buf->pages[buf->nr_pages]) {
 745                         fw_load_abort(fw_priv);
 746                         return -ENOMEM;
 747                 }
 748                 buf->nr_pages++;
 749         }
 750         return 0;
 751 }
 752
 753 /**
 754  * firmware_data_write - write method for firmware
 755  * @filp: open sysfs file
 756  * @kobj: kobject for the device
 757  * @bin_attr: bin_attr structure
 758  * @buffer: buffer being written
 759  * @offset: buffer offset for write in total data store area
 760  * @count: buffer size
 761  *
 762  *      Data written to the 'data' attribute will be later handed to
 763  *      the driver as a firmware image.
 764  **/
 765 static ssize_t firmware_data_write(struct file *filp, struct kobject *kobj,
 766                                    struct bin_attribute *bin_attr,
 767                                    char *buffer, loff_t offset, size_t count)
 768 {
 769         struct device *dev = kobj_to_dev(kobj);
 770         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 771         struct firmware_buf *buf;
 772         ssize_t retval;
 773
 774         if (!capable(CAP_SYS_RAWIO))
 775                 return -EPERM;
 776
 777         mutex_lock(&fw_lock);
 778         buf = fw_priv->buf;
 779         if (!buf || test_bit(FW_STATUS_DONE, &buf->status)) {
 780                 retval = -ENODEV;
 781                 goto out;
 782         }
 783
 784         retval = fw_realloc_buffer(fw_priv, offset + count);
 785         if (retval)
 786                 goto out;
 787
 788         retval = count;
 789
 790         while (count) {
 791                 void *page_data;
 792                 int page_nr = offset >> PAGE_SHIFT;
 793                 int page_ofs = offset & (PAGE_SIZE - 1);
 794                 int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
 795
 796                 page_data = kmap(buf->pages[page_nr]);
 797
 798                 memcpy(page_data + page_ofs, buffer, page_cnt);
 799
 800                 kunmap(buf->pages[page_nr]);
 801                 buffer += page_cnt;
 802                 offset += page_cnt;
 803                 count -= page_cnt;
 804         }
 805
 806         buf->size = max_t(size_t, offset, buf->size);
 807 out:
 808         mutex_unlock(&fw_lock);
 809         return retval;
 810 }
 811
 812 static struct bin_attribute firmware_attr_data = {
 813         .attr = { .name = "data", .mode = 0644 },
 814         .size = 0,
 815         .read = firmware_data_read,
 816         .write = firmware_data_write,
 817 };
 818
 819 static void firmware_class_timeout_work(struct work_struct *work)
 820 {
 821         struct firmware_priv *fw_priv = container_of(work,
 822                         struct firmware_priv, timeout_work.work);
 823
 824         mutex_lock(&fw_lock);
 825         fw_load_abort(fw_priv);
 826         mutex_unlock(&fw_lock);
 827 }
 828
 829 static struct firmware_priv *
 830 fw_create_instance(struct firmware *firmware, const char *fw_name,
 831                    struct device *device, bool uevent, bool nowait)
 832 {
 833         struct firmware_priv *fw_priv;
 834         struct device *f_dev;
 835
 836         fw_priv = kzalloc(sizeof(*fw_priv), GFP_KERNEL);
 837         if (!fw_priv) {
 838                 dev_err(device, "%s: kmalloc failed\n", __func__);
 839                 fw_priv = ERR_PTR(-ENOMEM);
 840                 goto exit;
 841         }
 842
 843         fw_priv->nowait = nowait;
 844         fw_priv->fw = firmware;
 845         INIT_DELAYED_WORK(&fw_priv->timeout_work,
 846                 firmware_class_timeout_work);
 847
 848         f_dev = &fw_priv->dev;
 849
 850         device_initialize(f_dev);
 851         dev_set_name(f_dev, "%s", fw_name);
 852         f_dev->parent = device;
 853         f_dev->class = &firmware_class;
 854 exit:
 855         return fw_priv;
 856 }
 857
 858 /* load a firmware via user helper */
 859 static int _request_firmware_load(struct firmware_priv *fw_priv, bool uevent,
 860                                   long timeout)
 861 {
 862         int retval = 0;
 863         struct device *f_dev = &fw_priv->dev;
 864         struct firmware_buf *buf = fw_priv->buf;
 865
 866         /* fall back on userspace loading */
 867         buf->is_paged_buf = true;
 868
 869         dev_set_uevent_suppress(f_dev, true);
 870
 871         retval = device_add(f_dev);
 872         if (retval) {
 873                 dev_err(f_dev, "%s: device_register failed\n", __func__);
 874                 goto err_put_dev;
 875         }
 876
 877         retval = device_create_bin_file(f_dev, &firmware_attr_data);
 878         if (retval) {
 879                 dev_err(f_dev, "%s: sysfs_create_bin_file failed\n", __func__);
 880                 goto err_del_dev;
 881         }
 882
 883         retval = device_create_file(f_dev, &dev_attr_loading);
 884         if (retval) {
 885                 dev_err(f_dev, "%s: device_create_file failed\n", __func__);
 886                 goto err_del_bin_attr;
 887         }
 888
 889         if (uevent) {
 890                 buf->need_uevent = true;
 891                 dev_set_uevent_suppress(f_dev, false);
 892                 dev_dbg(f_dev, "firmware: requesting %s\n", buf->fw_id);
 893                 if (timeout != MAX_SCHEDULE_TIMEOUT)
 894                         schedule_delayed_work(&fw_priv->timeout_work, timeout);
 895
 896                 kobject_uevent(&fw_priv->dev.kobj, KOBJ_ADD);
 897         }
 898
 899         mutex_lock(&fw_lock);
 900         list_add(&buf->pending_list, &pending_fw_head);
 901         mutex_unlock(&fw_lock);
 902
 903         wait_for_completion(&buf->completion);
 904
 905         cancel_delayed_work_sync(&fw_priv->timeout_work);
 906
 907         device_remove_file(f_dev, &dev_attr_loading);
 908 err_del_bin_attr:
 909         device_remove_bin_file(f_dev, &firmware_attr_data);
 910 err_del_dev:
 911         device_del(f_dev);
 912 err_put_dev:
 913         put_device(f_dev);
 914         return retval;
 915 }
 916
 917 static int fw_load_from_user_helper(struct firmware *firmware,
 918                                     const char *name, struct device *device,
 919                                     bool uevent, bool nowait, long timeout)
 920 {
 921         struct firmware_priv *fw_priv;
 922
 923         fw_priv = fw_create_instance(firmware, name, device, uevent, nowait);
 924         if (IS_ERR(fw_priv))
 925                 return PTR_ERR(fw_priv);
 926
 927         fw_priv->buf = firmware->priv;
 928         return _request_firmware_load(fw_priv, uevent, timeout);
 929 }
 930
 931 #ifdef CONFIG_PM_SLEEP
 932 /* kill pending requests without uevent to avoid blocking suspend */
 933 static void kill_requests_without_uevent(void)
 934 {
 935         struct firmware_buf *buf;
 936         struct firmware_buf *next;
 937
 938         mutex_lock(&fw_lock);
 939         list_for_each_entry_safe(buf, next, &pending_fw_head, pending_list) {
 940                 if (!buf->need_uevent)
 941                          __fw_load_abort(buf);
 942         }
 943         mutex_unlock(&fw_lock);
 944 }
 945 #endif
 946
 947 #else /* CONFIG_FW_LOADER_USER_HELPER */
 948 static inline int
 949 fw_load_from_user_helper(struct firmware *firmware, const char *name,
 950                          struct device *device, bool uevent, bool nowait,
 951                          long timeout)
 952 {
 953         return -ENOENT;
 954 }
 955
 956 /* No abort during direct loading */
 957 #define is_fw_load_aborted(buf) false
 958
 959 #ifdef CONFIG_PM_SLEEP
 960 static inline void kill_requests_without_uevent(void) { }
 961 #endif
 962
 963 #endif /* CONFIG_FW_LOADER_USER_HELPER */
 964
 965
 966 /* wait until the shared firmware_buf becomes ready (or error) */
 967 static int sync_cached_firmware_buf(struct firmware_buf *buf)
 968 {
 969         int ret = 0;
 970
 971         mutex_lock(&fw_lock);
 972         while (!test_bit(FW_STATUS_DONE, &buf->status)) {
 973                 if (is_fw_load_aborted(buf)) {
 974                         ret = -ENOENT;
 975                         break;
 976                 }
 977                 mutex_unlock(&fw_lock);
 978                 wait_for_completion(&buf->completion);
 979                 mutex_lock(&fw_lock);
 980         }
 981         mutex_unlock(&fw_lock);
 982         return ret;
 983 }
 984
 985 /* prepare firmware and firmware_buf structs;
 986  * return 0 if a firmware is already assigned, 1 if need to load one,
 987  * or a negative error code
 988  */
 989 static int
 990 _request_firmware_prepare(struct firmware **firmware_p, const char *name,
 991                           struct device *device)
 992 {
 993         struct firmware *firmware;
 994         struct firmware_buf *buf;
 995         int ret;
 996
 997         *firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
 998         if (!firmware) {
 999                 dev_err(device, "%s: kmalloc(struct firmware) failed\n",
1000                         __func__);
1001                 return -ENOMEM;
1002         }
1003
1004         if (fw_get_builtin_firmware(firmware, name)) {
1005                 dev_dbg(device, "firmware: using built-in firmware %s\n", name);
1006                 return 0; /* assigned */
1007         }
1008
1009         ret = fw_lookup_and_allocate_buf(name, &fw_cache, &buf);
1010
1011         /*
1012          * bind with 'buf' now to avoid warning in failure path
1013          * of requesting firmware.
1014          */
1015         firmware->priv = buf;
1016
1017         if (ret > 0) {
1018                 ret = sync_cached_firmware_buf(buf);
1019                 if (!ret) {
1020                         fw_set_page_data(buf, firmware);
1021                         return 0; /* assigned */
1022                 }
1023         }
1024
1025         if (ret < 0)
1026                 return ret;
1027         return 1; /* need to load */
1028 }
1029
1030 static int assign_firmware_buf(struct firmware *fw, struct device *device,
1031                                 bool skip_cache)
1032 {
1033         struct firmware_buf *buf = fw->priv;
1034
1035         mutex_lock(&fw_lock);
1036         if (!buf->size || is_fw_load_aborted(buf)) {
1037                 mutex_unlock(&fw_lock);
1038                 return -ENOENT;
1039         }
1040
1041         /*
1042          * add firmware name into devres list so that we can auto cache
1043          * and uncache firmware for device.
1044          *
1045          * device may has been deleted already, but the problem
1046          * should be fixed in devres or driver core.
1047          */
1048         if (device && !skip_cache)
1049                 fw_add_devm_name(device, buf->fw_id);
1050
1051         /*
1052          * After caching firmware image is started, let it piggyback
1053          * on request firmware.
1054          */
1055         if (buf->fwc->state == FW_LOADER_START_CACHE) {
1056                 if (fw_cache_piggyback_on_request(buf->fw_id))
1057                         kref_get(&buf->ref);
1058         }
1059
1060         /* pass the pages buffer to driver at the last minute */
1061         fw_set_page_data(buf, fw);
1062         mutex_unlock(&fw_lock);
1063         return 0;
1064 }
1065
1066 /* called from request_firmware() and request_firmware_work_func() */
1067 static int
1068 _request_firmware(const struct firmware **firmware_p, const char *name,
1069                   struct device *device, bool uevent, bool nowait)
1070 {
1071         struct firmware *fw;
1072         long timeout;
1073         int ret;
1074
1075         if (!firmware_p)
1076                 return -EINVAL;
1077
1078         ret = _request_firmware_prepare(&fw, name, device);
1079         if (ret <= 0) /* error or already assigned */
1080                 goto out;
1081
1082         ret = 0;
1083         timeout = firmware_loading_timeout();
1084         if (nowait) {
1085                 timeout = usermodehelper_read_lock_wait(timeout);
1086                 if (!timeout) {
1087                         dev_dbg(device, "firmware: %s loading timed out\n",
1088                                 name);
1089                         ret = -EBUSY;
1090                         goto out;
1091                 }
1092         } else {
1093                 ret = usermodehelper_read_trylock();
1094                 if (WARN_ON(ret)) {
1095                         dev_err(device, "firmware: %s will not be loaded\n",
1096                                 name);
1097                         goto out;
1098                 }
1099         }
1100
1101         if (!fw_get_filesystem_firmware(device, fw->priv))
1102                 ret = fw_load_from_user_helper(fw, name, device,
1103                                                uevent, nowait, timeout);
1104
1105         /* don't cache firmware handled without uevent */
1106         if (!ret)
1107                 ret = assign_firmware_buf(fw, device, !uevent);
1108
1109         usermodehelper_read_unlock();
1110
1111  out:
1112         if (ret < 0) {
1113                 release_firmware(fw);
1114                 fw = NULL;
1115         }
1116
1117         *firmware_p = fw;
1118         return ret;
1119 }
1120
1121 /**
1122  * request_firmware: - send firmware request and wait for it
1123  * @firmware_p: pointer to firmware image
1124  * @name: name of firmware file
1125  * @device: device for which firmware is being loaded
1126  *
1127  *      @firmware_p will be used to return a firmware image by the name
1128  *      of @name for device @device.
1129  *
1130  *      Should be called from user context where sleeping is allowed.
1131  *
1132  *      @name will be used as $FIRMWARE in the uevent environment and
1133  *      should be distinctive enough not to be confused with any other
1134  *      firmware image for this or any other device.
1135  *
1136  *      Caller must hold the reference count of @device.
1137  *
1138  *      The function can be called safely inside device's suspend and
1139  *      resume callback.
1140  **/
1141 int
1142 request_firmware(const struct firmware **firmware_p, const char *name,
1143                  struct device *device)
1144 {
1145         int ret;
1146
1147         /* Need to pin this module until return */
1148         __module_get(THIS_MODULE);
1149         ret = _request_firmware(firmware_p, name, device, true, false);
1150         module_put(THIS_MODULE);
1151         return ret;
1152 }
1153 EXPORT_SYMBOL(request_firmware);
1154
1155 /**
1156  * release_firmware: - release the resource associated with a firmware image
1157  * @fw: firmware resource to release
1158  **/
1159 void release_firmware(const struct firmware *fw)
1160 {
1161         if (fw) {
1162                 if (!fw_is_builtin_firmware(fw))
1163                         firmware_free_data(fw);
1164                 kfree(fw);
1165         }
1166 }
1167 EXPORT_SYMBOL(release_firmware);
1168
1169 /* Async support */
1170 struct firmware_work {
1171         struct work_struct work;
1172         struct module *module;
1173         const char *name;
1174         struct device *device;
1175         void *context;
1176         void (*cont)(const struct firmware *fw, void *context);
1177         bool uevent;
1178 };
1179
1180 static void request_firmware_work_func(struct work_struct *work)
1181 {
1182         struct firmware_work *fw_work;
1183         const struct firmware *fw;
1184
1185         fw_work = container_of(work, struct firmware_work, work);
1186
1187         _request_firmware(&fw, fw_work->name, fw_work->device,
1188                           fw_work->uevent, true);
1189         fw_work->cont(fw, fw_work->context);
1190         put_device(fw_work->device); /* taken in request_firmware_nowait() */
1191
1192         module_put(fw_work->module);
1193         kfree(fw_work);
1194 }
1195
1196 /**
1197  * request_firmware_nowait - asynchronous version of request_firmware
1198  * @module: module requesting the firmware
1199  * @uevent: sends uevent to copy the firmware image if this flag
1200  *      is non-zero else the firmware copy must be done manually.
1201  * @name: name of firmware file
1202  * @device: device for which firmware is being loaded
1203  * @gfp: allocation flags
1204  * @context: will be passed over to @cont, and
1205  *      @fw may be %NULL if firmware request fails.
1206  * @cont: function will be called asynchronously when the firmware
1207  *      request is over.
1208  *
1209  *      Caller must hold the reference count of @device.
1210  *
1211  *      Asynchronous variant of request_firmware() for user contexts:
1212  *              - sleep for as small periods as possible since it may
1213  *              increase kernel boot time of built-in device drivers
1214  *              requesting firmware in their ->probe() methods, if
1215  *              @gfp is GFP_KERNEL.
1216  *
1217  *              - can't sleep at all if @gfp is GFP_ATOMIC.
1218  **/
1219 int
1220 request_firmware_nowait(
1221         struct module *module, bool uevent,
1222         const char *name, struct device *device, gfp_t gfp, void *context,
1223         void (*cont)(const struct firmware *fw, void *context))
1224 {
1225         struct firmware_work *fw_work;
1226
1227         fw_work = kzalloc(sizeof (struct firmware_work), gfp);
1228         if (!fw_work)
1229                 return -ENOMEM;
1230
1231         fw_work->module = module;
1232         fw_work->name = name;
1233         fw_work->device = device;
1234         fw_work->context = context;
1235         fw_work->cont = cont;
1236         fw_work->uevent = uevent;
1237
1238         if (!try_module_get(module)) {
1239                 kfree(fw_work);
1240                 return -EFAULT;
1241         }
1242
1243         get_device(fw_work->device);
1244         INIT_WORK(&fw_work->work, request_firmware_work_func);
1245         schedule_work(&fw_work->work);
1246         return 0;
1247 }
1248 EXPORT_SYMBOL(request_firmware_nowait);
1249
1250 /**
1251  * cache_firmware - cache one firmware image in kernel memory space
1252  * @fw_name: the firmware image name
1253  *
1254  * Cache firmware in kernel memory so that drivers can use it when
1255  * system isn't ready for them to request firmware image from userspace.
1256  * Once it returns successfully, driver can use request_firmware or its
1257  * nowait version to get the cached firmware without any interacting
1258  * with userspace
1259  *
1260  * Return 0 if the firmware image has been cached successfully
1261  * Return !0 otherwise
1262  *
1263  */
1264 static int cache_firmware(const char *fw_name)
1265 {
1266         int ret;
1267         const struct firmware *fw;
1268
1269         pr_debug("%s: %s\n", __func__, fw_name);
1270
1271         ret = request_firmware(&fw, fw_name, NULL);
1272         if (!ret)
1273                 kfree(fw);
1274
1275         pr_debug("%s: %s ret=%d\n", __func__, fw_name, ret);
1276
1277         return ret;
1278 }
1279
1280 /**
1281  * uncache_firmware - remove one cached firmware image
1282  * @fw_name: the firmware image name
1283  *
1284  * Uncache one firmware image which has been cached successfully
1285  * before.
1286  *
1287  * Return 0 if the firmware cache has been removed successfully
1288  * Return !0 otherwise
1289  *
1290  */
1291 static int uncache_firmware(const char *fw_name)
1292 {
1293         struct firmware_buf *buf;
1294         struct firmware fw;
1295
1296         pr_debug("%s: %s\n", __func__, fw_name);
1297
1298         if (fw_get_builtin_firmware(&fw, fw_name))
1299                 return 0;
1300
1301         buf = fw_lookup_buf(fw_name);
1302         if (buf) {
1303                 fw_free_buf(buf);
1304                 return 0;
1305         }
1306
1307         return -EINVAL;
1308 }
1309
1310 #ifdef CONFIG_PM_SLEEP
1311 static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
1312
1313 static struct fw_cache_entry *alloc_fw_cache_entry(const char *name)
1314 {
1315         struct fw_cache_entry *fce;
1316
1317         fce = kzalloc(sizeof(*fce) + strlen(name) + 1, GFP_ATOMIC);
1318         if (!fce)
1319                 goto exit;
1320
1321         strcpy(fce->name, name);
1322 exit:
1323         return fce;
1324 }
1325
1326 static int __fw_entry_found(const char *name)
1327 {
1328         struct firmware_cache *fwc = &fw_cache;
1329         struct fw_cache_entry *fce;
1330
1331         list_for_each_entry(fce, &fwc->fw_names, list) {
1332                 if (!strcmp(fce->name, name))
1333                         return 1;
1334         }
1335         return 0;
1336 }
1337
1338 static int fw_cache_piggyback_on_request(const char *name)
1339 {
1340         struct firmware_cache *fwc = &fw_cache;
1341         struct fw_cache_entry *fce;
1342         int ret = 0;
1343
1344         spin_lock(&fwc->name_lock);
1345         if (__fw_entry_found(name))
1346                 goto found;
1347
1348         fce = alloc_fw_cache_entry(name);
1349         if (fce) {
1350                 ret = 1;
1351                 list_add(&fce->list, &fwc->fw_names);
1352                 pr_debug("%s: fw: %s\n", __func__, name);
1353         }
1354 found:
1355         spin_unlock(&fwc->name_lock);
1356         return ret;
1357 }
1358
1359 static void free_fw_cache_entry(struct fw_cache_entry *fce)
1360 {
1361         kfree(fce);
1362 }
1363
1364 static void __async_dev_cache_fw_image(void *fw_entry,
1365                                        async_cookie_t cookie)
1366 {
1367         struct fw_cache_entry *fce = fw_entry;
1368         struct firmware_cache *fwc = &fw_cache;
1369         int ret;
1370
1371         ret = cache_firmware(fce->name);
1372         if (ret) {
1373                 spin_lock(&fwc->name_lock);
1374                 list_del(&fce->list);
1375                 spin_unlock(&fwc->name_lock);
1376
1377                 free_fw_cache_entry(fce);
1378         }
1379 }
1380
1381 /* called with dev->devres_lock held */
1382 static void dev_create_fw_entry(struct device *dev, void *res,
1383                                 void *data)
1384 {
1385         struct fw_name_devm *fwn = res;
1386         const char *fw_name = fwn->name;
1387         struct list_head *head = data;
1388         struct fw_cache_entry *fce;
1389
1390         fce = alloc_fw_cache_entry(fw_name);
1391         if (fce)
1392                 list_add(&fce->list, head);
1393 }
1394
1395 static int devm_name_match(struct device *dev, void *res,
1396                            void *match_data)
1397 {
1398         struct fw_name_devm *fwn = res;
1399         return (fwn->magic == (unsigned long)match_data);
1400 }
1401
1402 static void dev_cache_fw_image(struct device *dev, void *data)
1403 {
1404         LIST_HEAD(todo);
1405         struct fw_cache_entry *fce;
1406         struct fw_cache_entry *fce_next;
1407         struct firmware_cache *fwc = &fw_cache;
1408
1409         devres_for_each_res(dev, fw_name_devm_release,
1410                             devm_name_match, &fw_cache,
1411                             dev_create_fw_entry, &todo);
1412
1413         list_for_each_entry_safe(fce, fce_next, &todo, list) {
1414                 list_del(&fce->list);
1415
1416                 spin_lock(&fwc->name_lock);
1417                 /* only one cache entry for one firmware */
1418                 if (!__fw_entry_found(fce->name)) {
1419                         list_add(&fce->list, &fwc->fw_names);
1420                 } else {
1421                         free_fw_cache_entry(fce);
1422                         fce = NULL;
1423                 }
1424                 spin_unlock(&fwc->name_lock);
1425
1426                 if (fce)
1427                         async_schedule_domain(__async_dev_cache_fw_image,
1428                                               (void *)fce,
1429                                               &fw_cache_domain);
1430         }
1431 }
1432
1433 static void __device_uncache_fw_images(void)
1434 {
1435         struct firmware_cache *fwc = &fw_cache;
1436         struct fw_cache_entry *fce;
1437
1438         spin_lock(&fwc->name_lock);
1439         while (!list_empty(&fwc->fw_names)) {
1440                 fce = list_entry(fwc->fw_names.next,
1441                                 struct fw_cache_entry, list);
1442                 list_del(&fce->list);
1443                 spin_unlock(&fwc->name_lock);
1444
1445                 uncache_firmware(fce->name);
1446                 free_fw_cache_entry(fce);
1447
1448                 spin_lock(&fwc->name_lock);
1449         }
1450         spin_unlock(&fwc->name_lock);
1451 }
1452
1453 /**
1454  * device_cache_fw_images - cache devices' firmware
1455  *
1456  * If one device called request_firmware or its nowait version
1457  * successfully before, the firmware names are recored into the
1458  * device's devres link list, so device_cache_fw_images can call
1459  * cache_firmware() to cache these firmwares for the device,
1460  * then the device driver can load its firmwares easily at
1461  * time when system is not ready to complete loading firmware.
1462  */
1463 static void device_cache_fw_images(void)
1464 {
1465         struct firmware_cache *fwc = &fw_cache;
1466         int old_timeout;
1467         DEFINE_WAIT(wait);
1468
1469         pr_debug("%s\n", __func__);
1470
1471         /* cancel uncache work */
1472         cancel_delayed_work_sync(&fwc->work);
1473
1474         /*
1475          * use small loading timeout for caching devices' firmware
1476          * because all these firmware images have been loaded
1477          * successfully at lease once, also system is ready for
1478          * completing firmware loading now. The maximum size of
1479          * firmware in current distributions is about 2M bytes,
1480          * so 10 secs should be enough.
1481          */
1482         old_timeout = loading_timeout;
1483         loading_timeout = 10;
1484
1485         mutex_lock(&fw_lock);
1486         fwc->state = FW_LOADER_START_CACHE;
1487         dpm_for_each_dev(NULL, dev_cache_fw_image);
1488         mutex_unlock(&fw_lock);
1489
1490         /* wait for completion of caching firmware for all devices */
1491         async_synchronize_full_domain(&fw_cache_domain);
1492
1493         loading_timeout = old_timeout;
1494 }
1495
1496 /**
1497  * device_uncache_fw_images - uncache devices' firmware
1498  *
1499  * uncache all firmwares which have been cached successfully
1500  * by device_uncache_fw_images earlier
1501  */
1502 static void device_uncache_fw_images(void)
1503 {
1504         pr_debug("%s\n", __func__);
1505         __device_uncache_fw_images();
1506 }
1507
1508 static void device_uncache_fw_images_work(struct work_struct *work)
1509 {
1510         device_uncache_fw_images();
1511 }
1512
1513 /**
1514  * device_uncache_fw_images_delay - uncache devices firmwares
1515  * @delay: number of milliseconds to delay uncache device firmwares
1516  *
1517  * uncache all devices's firmwares which has been cached successfully
1518  * by device_cache_fw_images after @delay milliseconds.
1519  */
1520 static void device_uncache_fw_images_delay(unsigned long delay)
1521 {
1522         schedule_delayed_work(&fw_cache.work,
1523                         msecs_to_jiffies(delay));
1524 }
1525
1526 static int fw_pm_notify(struct notifier_block *notify_block,
1527                         unsigned long mode, void *unused)
1528 {
1529         switch (mode) {
1530         case PM_HIBERNATION_PREPARE:
1531         case PM_SUSPEND_PREPARE:
1532                 kill_requests_without_uevent();
1533                 device_cache_fw_images();
1534                 break;
1535
1536         case PM_POST_SUSPEND:
1537         case PM_POST_HIBERNATION:
1538         case PM_POST_RESTORE:
1539                 /*
1540                  * In case that system sleep failed and syscore_suspend is
1541                  * not called.
1542                  */
1543                 mutex_lock(&fw_lock);
1544                 fw_cache.state = FW_LOADER_NO_CACHE;
1545                 mutex_unlock(&fw_lock);
1546
1547                 device_uncache_fw_images_delay(10 * MSEC_PER_SEC);
1548                 break;
1549         }
1550
1551         return 0;
1552 }
1553
1554 /* stop caching firmware once syscore_suspend is reached */
1555 static int fw_suspend(void)
1556 {
1557         fw_cache.state = FW_LOADER_NO_CACHE;
1558         return 0;
1559 }
1560
1561 static struct syscore_ops fw_syscore_ops = {
1562         .suspend = fw_suspend,
1563 };
1564 #else
1565 static int fw_cache_piggyback_on_request(const char *name)
1566 {
1567         return 0;
1568 }
1569 #endif
1570
1571 static void __init fw_cache_init(void)
1572 {
1573         spin_lock_init(&fw_cache.lock);
1574         INIT_LIST_HEAD(&fw_cache.head);
1575         fw_cache.state = FW_LOADER_NO_CACHE;
1576
1577 #ifdef CONFIG_PM_SLEEP
1578         spin_lock_init(&fw_cache.name_lock);
1579         INIT_LIST_HEAD(&fw_cache.fw_names);
1580
1581         INIT_DELAYED_WORK(&fw_cache.work,
1582                           device_uncache_fw_images_work);
1583
1584         fw_cache.pm_notify.notifier_call = fw_pm_notify;
1585         register_pm_notifier(&fw_cache.pm_notify);
1586
1587         register_syscore_ops(&fw_syscore_ops);
1588 #endif
1589 }
1590
1591 static int __init firmware_class_init(void)
1592 {
1593         fw_cache_init();
1594 #ifdef CONFIG_FW_LOADER_USER_HELPER
1595         register_reboot_notifier(&fw_shutdown_nb);
1596         return class_register(&firmware_class);
1597 #else
1598         return 0;
1599 #endif
1600 }
1601
1602 static void __exit firmware_class_exit(void)
1603 {
1604 #ifdef CONFIG_PM_SLEEP
1605         unregister_syscore_ops(&fw_syscore_ops);
1606         unregister_pm_notifier(&fw_cache.pm_notify);
1607 #endif
1608 #ifdef CONFIG_FW_LOADER_USER_HELPER
1609         unregister_reboot_notifier(&fw_shutdown_nb);
1610         class_unregister(&firmware_class);
1611 #endif
1612 }
1613
1614 fs_initcall(firmware_class_init);
1615 module_exit(firmware_class_exit);