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