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 void __fw_free_buf(struct kref *ref)
 222 {
 223         struct firmware_buf *buf = to_fwbuf(ref);
 224         struct firmware_cache *fwc = buf->fwc;
 225
 226         pr_debug("%s: fw-%s buf=%p data=%p size=%u\n",
 227                  __func__, buf->fw_id, buf, buf->data,
 228                  (unsigned int)buf->size);
 229
 230         list_del(&buf->list);
 231         spin_unlock(&fwc->lock);
 232
 233 #ifdef CONFIG_FW_LOADER_USER_HELPER
 234         if (buf->is_paged_buf) {
 235                 int i;
 236                 vunmap(buf->data);
 237                 for (i = 0; i < buf->nr_pages; i++)
 238                         __free_page(buf->pages[i]);
 239                 kfree(buf->pages);
 240         } else
 241 #endif
 242                 vfree(buf->data);
 243         kfree(buf);
 244 }
 245
 246 static void fw_free_buf(struct firmware_buf *buf)
 247 {
 248         struct firmware_cache *fwc = buf->fwc;
 249         spin_lock(&fwc->lock);
 250         if (!kref_put(&buf->ref, __fw_free_buf))
 251                 spin_unlock(&fwc->lock);
 252 }
 253
 254 /* direct firmware loading support */
 255 static char fw_path_para[256];
 256 static const char * const fw_path[] = {
 257         fw_path_para,
 258         "/lib/firmware/updates/" UTS_RELEASE,
 259         "/lib/firmware/updates",
 260         "/lib/firmware/" UTS_RELEASE,
 261         "/lib/firmware"
 262 };
 263
 264 /*
 265  * Typical usage is that passing 'firmware_class.path=$CUSTOMIZED_PATH'
 266  * from kernel command line because firmware_class is generally built in
 267  * kernel instead of module.
 268  */
 269 module_param_string(path, fw_path_para, sizeof(fw_path_para), 0644);
 270 MODULE_PARM_DESC(path, "customized firmware image search path with a higher priority than default path");
 271
 272 /* Don't inline this: 'struct kstat' is biggish */
 273 static noinline_for_stack long fw_file_size(struct file *file)
 274 {
 275         struct kstat st;
 276         if (vfs_getattr(&file->f_path, &st))
 277                 return -1;
 278         if (!S_ISREG(st.mode))
 279                 return -1;
 280         if (st.size != (long)st.size)
 281                 return -1;
 282         return st.size;
 283 }
 284
 285 static int fw_read_file_contents(struct file *file, struct firmware_buf *fw_buf)
 286 {
 287         long size;
 288         char *buf;
 289         int rc;
 290
 291         size = fw_file_size(file);
 292         if (size <= 0)
 293                 return -EINVAL;
 294         buf = vmalloc(size);
 295         if (!buf)
 296                 return -ENOMEM;
 297         rc = kernel_read(file, 0, buf, size);
 298         if (rc != size) {
 299                 if (rc > 0)
 300                         rc = -EIO;
 301                 vfree(buf);
 302                 return rc;
 303         }
 304         fw_buf->data = buf;
 305         fw_buf->size = size;
 306         return 0;
 307 }
 308
 309 static int fw_get_filesystem_firmware(struct device *device,
 310                                        struct firmware_buf *buf)
 311 {
 312         int i;
 313         int rc = -ENOENT;
 314         char *path = __getname();
 315
 316         for (i = 0; i < ARRAY_SIZE(fw_path); i++) {
 317                 struct file *file;
 318
 319                 /* skip the unset customized path */
 320                 if (!fw_path[i][0])
 321                         continue;
 322
 323                 snprintf(path, PATH_MAX, "%s/%s", fw_path[i], buf->fw_id);
 324
 325                 file = filp_open(path, O_RDONLY, 0);
 326                 if (IS_ERR(file))
 327                         continue;
 328                 rc = fw_read_file_contents(file, buf);
 329                 fput(file);
 330                 if (rc)
 331                         dev_warn(device, "firmware, attempted to load %s, but failed with error %d\n",
 332                                 path, rc);
 333                 else
 334                         break;
 335         }
 336         __putname(path);
 337
 338         if (!rc) {
 339                 dev_dbg(device, "firmware: direct-loading firmware %s\n",
 340                         buf->fw_id);
 341                 mutex_lock(&fw_lock);
 342                 set_bit(FW_STATUS_DONE, &buf->status);
 343                 complete_all(&buf->completion);
 344                 mutex_unlock(&fw_lock);
 345         }
 346
 347         return rc;
 348 }
 349
 350 /* firmware holds the ownership of pages */
 351 static void firmware_free_data(const struct firmware *fw)
 352 {
 353         /* Loaded directly? */
 354         if (!fw->priv) {
 355                 vfree(fw->data);
 356                 return;
 357         }
 358         fw_free_buf(fw->priv);
 359 }
 360
 361 /* store the pages buffer info firmware from buf */
 362 static void fw_set_page_data(struct firmware_buf *buf, struct firmware *fw)
 363 {
 364         fw->priv = buf;
 365 #ifdef CONFIG_FW_LOADER_USER_HELPER
 366         fw->pages = buf->pages;
 367 #endif
 368         fw->size = buf->size;
 369         fw->data = buf->data;
 370
 371         pr_debug("%s: fw-%s buf=%p data=%p size=%u\n",
 372                  __func__, buf->fw_id, buf, buf->data,
 373                  (unsigned int)buf->size);
 374 }
 375
 376 #ifdef CONFIG_PM_SLEEP
 377 static void fw_name_devm_release(struct device *dev, void *res)
 378 {
 379         struct fw_name_devm *fwn = res;
 380
 381         if (fwn->magic == (unsigned long)&fw_cache)
 382                 pr_debug("%s: fw_name-%s devm-%p released\n",
 383                                 __func__, fwn->name, res);
 384 }
 385
 386 static int fw_devm_match(struct device *dev, void *res,
 387                 void *match_data)
 388 {
 389         struct fw_name_devm *fwn = res;
 390
 391         return (fwn->magic == (unsigned long)&fw_cache) &&
 392                 !strcmp(fwn->name, match_data);
 393 }
 394
 395 static struct fw_name_devm *fw_find_devm_name(struct device *dev,
 396                 const char *name)
 397 {
 398         struct fw_name_devm *fwn;
 399
 400         fwn = devres_find(dev, fw_name_devm_release,
 401                           fw_devm_match, (void *)name);
 402         return fwn;
 403 }
 404
 405 /* add firmware name into devres list */
 406 static int fw_add_devm_name(struct device *dev, const char *name)
 407 {
 408         struct fw_name_devm *fwn;
 409
 410         fwn = fw_find_devm_name(dev, name);
 411         if (fwn)
 412                 return 1;
 413
 414         fwn = devres_alloc(fw_name_devm_release, sizeof(struct fw_name_devm) +
 415                            strlen(name) + 1, GFP_KERNEL);
 416         if (!fwn)
 417                 return -ENOMEM;
 418
 419         fwn->magic = (unsigned long)&fw_cache;
 420         strcpy(fwn->name, name);
 421         devres_add(dev, fwn);
 422
 423         return 0;
 424 }
 425 #else
 426 static int fw_add_devm_name(struct device *dev, const char *name)
 427 {
 428         return 0;
 429 }
 430 #endif
 431
 432
 433 /*
 434  * user-mode helper code
 435  */
 436 #ifdef CONFIG_FW_LOADER_USER_HELPER
 437 struct firmware_priv {
 438         struct delayed_work timeout_work;
 439         bool nowait;
 440         struct device dev;
 441         struct firmware_buf *buf;
 442         struct firmware *fw;
 443 };
 444
 445 static struct firmware_priv *to_firmware_priv(struct device *dev)
 446 {
 447         return container_of(dev, struct firmware_priv, dev);
 448 }
 449
 450 static void __fw_load_abort(struct firmware_buf *buf)
 451 {
 452         /*
 453          * There is a small window in which user can write to 'loading'
 454          * between loading done and disappearance of 'loading'
 455          */
 456         if (test_bit(FW_STATUS_DONE, &buf->status))
 457                 return;
 458
 459         list_del_init(&buf->pending_list);
 460         set_bit(FW_STATUS_ABORT, &buf->status);
 461         complete_all(&buf->completion);
 462 }
 463
 464 static void fw_load_abort(struct firmware_priv *fw_priv)
 465 {
 466         struct firmware_buf *buf = fw_priv->buf;
 467
 468         __fw_load_abort(buf);
 469
 470         /* avoid user action after loading abort */
 471         fw_priv->buf = NULL;
 472 }
 473
 474 #define is_fw_load_aborted(buf) \
 475         test_bit(FW_STATUS_ABORT, &(buf)->status)
 476
 477 static LIST_HEAD(pending_fw_head);
 478
 479 /* reboot notifier for avoid deadlock with usermode_lock */
 480 static int fw_shutdown_notify(struct notifier_block *unused1,
 481                               unsigned long unused2, void *unused3)
 482 {
 483         mutex_lock(&fw_lock);
 484         while (!list_empty(&pending_fw_head))
 485                 __fw_load_abort(list_first_entry(&pending_fw_head,
 486                                                struct firmware_buf,
 487                                                pending_list));
 488         mutex_unlock(&fw_lock);
 489         return NOTIFY_DONE;
 490 }
 491
 492 static struct notifier_block fw_shutdown_nb = {
 493         .notifier_call = fw_shutdown_notify,
 494 };
 495
 496 static ssize_t timeout_show(struct class *class, struct class_attribute *attr,
 497                             char *buf)
 498 {
 499         return sprintf(buf, "%d\n", loading_timeout);
 500 }
 501
 502 /**
 503  * firmware_timeout_store - set number of seconds to wait for firmware
 504  * @class: device class pointer
 505  * @attr: device attribute pointer
 506  * @buf: buffer to scan for timeout value
 507  * @count: number of bytes in @buf
 508  *
 509  *      Sets the number of seconds to wait for the firmware.  Once
 510  *      this expires an error will be returned to the driver and no
 511  *      firmware will be provided.
 512  *
 513  *      Note: zero means 'wait forever'.
 514  **/
 515 static ssize_t timeout_store(struct class *class, struct class_attribute *attr,
 516                              const char *buf, size_t count)
 517 {
 518         loading_timeout = simple_strtol(buf, NULL, 10);
 519         if (loading_timeout < 0)
 520                 loading_timeout = 0;
 521
 522         return count;
 523 }
 524
 525 static struct class_attribute firmware_class_attrs[] = {
 526         __ATTR_RW(timeout),
 527         __ATTR_NULL
 528 };
 529
 530 static void fw_dev_release(struct device *dev)
 531 {
 532         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 533
 534         kfree(fw_priv);
 535 }
 536
 537 static int firmware_uevent(struct device *dev, struct kobj_uevent_env *env)
 538 {
 539         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 540
 541         if (add_uevent_var(env, "FIRMWARE=%s", fw_priv->buf->fw_id))
 542                 return -ENOMEM;
 543         if (add_uevent_var(env, "TIMEOUT=%i", loading_timeout))
 544                 return -ENOMEM;
 545         if (add_uevent_var(env, "ASYNC=%d", fw_priv->nowait))
 546                 return -ENOMEM;
 547
 548         return 0;
 549 }
 550
 551 static struct class firmware_class = {
 552         .name           = "firmware",
 553         .class_attrs    = firmware_class_attrs,
 554         .dev_uevent     = firmware_uevent,
 555         .dev_release    = fw_dev_release,
 556 };
 557
 558 static ssize_t firmware_loading_show(struct device *dev,
 559                                      struct device_attribute *attr, char *buf)
 560 {
 561         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 562         int loading = 0;
 563
 564         mutex_lock(&fw_lock);
 565         if (fw_priv->buf)
 566                 loading = test_bit(FW_STATUS_LOADING, &fw_priv->buf->status);
 567         mutex_unlock(&fw_lock);
 568
 569         return sprintf(buf, "%d\n", loading);
 570 }
 571
 572 /* Some architectures don't have PAGE_KERNEL_RO */
 573 #ifndef PAGE_KERNEL_RO
 574 #define PAGE_KERNEL_RO PAGE_KERNEL
 575 #endif
 576
 577 /* one pages buffer should be mapped/unmapped only once */
 578 static int fw_map_pages_buf(struct firmware_buf *buf)
 579 {
 580         if (!buf->is_paged_buf)
 581                 return 0;
 582
 583         if (buf->data)
 584                 vunmap(buf->data);
 585         buf->data = vmap(buf->pages, buf->nr_pages, 0, PAGE_KERNEL_RO);
 586         if (!buf->data)
 587                 return -ENOMEM;
 588         return 0;
 589 }
 590
 591 /**
 592  * firmware_loading_store - set value in the 'loading' control file
 593  * @dev: device pointer
 594  * @attr: device attribute pointer
 595  * @buf: buffer to scan for loading control value
 596  * @count: number of bytes in @buf
 597  *
 598  *      The relevant values are:
 599  *
 600  *       1: Start a load, discarding any previous partial load.
 601  *       0: Conclude the load and hand the data to the driver code.
 602  *      -1: Conclude the load with an error and discard any written data.
 603  **/
 604 static ssize_t firmware_loading_store(struct device *dev,
 605                                       struct device_attribute *attr,
 606                                       const char *buf, size_t count)
 607 {
 608         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 609         struct firmware_buf *fw_buf;
 610         int loading = simple_strtol(buf, NULL, 10);
 611         int i;
 612
 613         mutex_lock(&fw_lock);
 614         fw_buf = fw_priv->buf;
 615         if (!fw_buf)
 616                 goto out;
 617
 618         switch (loading) {
 619         case 1:
 620                 /* discarding any previous partial load */
 621                 if (!test_bit(FW_STATUS_DONE, &fw_buf->status)) {
 622                         for (i = 0; i < fw_buf->nr_pages; i++)
 623                                 __free_page(fw_buf->pages[i]);
 624                         kfree(fw_buf->pages);
 625                         fw_buf->pages = NULL;
 626                         fw_buf->page_array_size = 0;
 627                         fw_buf->nr_pages = 0;
 628                         set_bit(FW_STATUS_LOADING, &fw_buf->status);
 629                 }
 630                 break;
 631         case 0:
 632                 if (test_bit(FW_STATUS_LOADING, &fw_buf->status)) {
 633                         set_bit(FW_STATUS_DONE, &fw_buf->status);
 634                         clear_bit(FW_STATUS_LOADING, &fw_buf->status);
 635
 636                         /*
 637                          * Several loading requests may be pending on
 638                          * one same firmware buf, so let all requests
 639                          * see the mapped 'buf->data' once the loading
 640                          * is completed.
 641                          * */
 642                         fw_map_pages_buf(fw_buf);
 643                         list_del_init(&fw_buf->pending_list);
 644                         complete_all(&fw_buf->completion);
 645                         break;
 646                 }
 647                 /* fallthrough */
 648         default:
 649                 dev_err(dev, "%s: unexpected value (%d)\n", __func__, loading);
 650                 /* fallthrough */
 651         case -1:
 652                 fw_load_abort(fw_priv);
 653                 break;
 654         }
 655 out:
 656         mutex_unlock(&fw_lock);
 657         return count;
 658 }
 659
 660 static DEVICE_ATTR(loading, 0644, firmware_loading_show, firmware_loading_store);
 661
 662 static ssize_t firmware_data_read(struct file *filp, struct kobject *kobj,
 663                                   struct bin_attribute *bin_attr,
 664                                   char *buffer, loff_t offset, size_t count)
 665 {
 666         struct device *dev = kobj_to_dev(kobj);
 667         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 668         struct firmware_buf *buf;
 669         ssize_t ret_count;
 670
 671         mutex_lock(&fw_lock);
 672         buf = fw_priv->buf;
 673         if (!buf || test_bit(FW_STATUS_DONE, &buf->status)) {
 674                 ret_count = -ENODEV;
 675                 goto out;
 676         }
 677         if (offset > buf->size) {
 678                 ret_count = 0;
 679                 goto out;
 680         }
 681         if (count > buf->size - offset)
 682                 count = buf->size - offset;
 683
 684         ret_count = count;
 685
 686         while (count) {
 687                 void *page_data;
 688                 int page_nr = offset >> PAGE_SHIFT;
 689                 int page_ofs = offset & (PAGE_SIZE-1);
 690                 int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
 691
 692                 page_data = kmap(buf->pages[page_nr]);
 693
 694                 memcpy(buffer, page_data + page_ofs, page_cnt);
 695
 696                 kunmap(buf->pages[page_nr]);
 697                 buffer += page_cnt;
 698                 offset += page_cnt;
 699                 count -= page_cnt;
 700         }
 701 out:
 702         mutex_unlock(&fw_lock);
 703         return ret_count;
 704 }
 705
 706 static int fw_realloc_buffer(struct firmware_priv *fw_priv, int min_size)
 707 {
 708         struct firmware_buf *buf = fw_priv->buf;
 709         int pages_needed = ALIGN(min_size, PAGE_SIZE) >> PAGE_SHIFT;
 710
 711         /* If the array of pages is too small, grow it... */
 712         if (buf->page_array_size < pages_needed) {
 713                 int new_array_size = max(pages_needed,
 714                                          buf->page_array_size * 2);
 715                 struct page **new_pages;
 716
 717                 new_pages = kmalloc(new_array_size * sizeof(void *),
 718                                     GFP_KERNEL);
 719                 if (!new_pages) {
 720                         fw_load_abort(fw_priv);
 721                         return -ENOMEM;
 722                 }
 723                 memcpy(new_pages, buf->pages,
 724                        buf->page_array_size * sizeof(void *));
 725                 memset(&new_pages[buf->page_array_size], 0, sizeof(void *) *
 726                        (new_array_size - buf->page_array_size));
 727                 kfree(buf->pages);
 728                 buf->pages = new_pages;
 729                 buf->page_array_size = new_array_size;
 730         }
 731
 732         while (buf->nr_pages < pages_needed) {
 733                 buf->pages[buf->nr_pages] =
 734                         alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
 735
 736                 if (!buf->pages[buf->nr_pages]) {
 737                         fw_load_abort(fw_priv);
 738                         return -ENOMEM;
 739                 }
 740                 buf->nr_pages++;
 741         }
 742         return 0;
 743 }
 744
 745 /**
 746  * firmware_data_write - write method for firmware
 747  * @filp: open sysfs file
 748  * @kobj: kobject for the device
 749  * @bin_attr: bin_attr structure
 750  * @buffer: buffer being written
 751  * @offset: buffer offset for write in total data store area
 752  * @count: buffer size
 753  *
 754  *      Data written to the 'data' attribute will be later handed to
 755  *      the driver as a firmware image.
 756  **/
 757 static ssize_t firmware_data_write(struct file *filp, struct kobject *kobj,
 758                                    struct bin_attribute *bin_attr,
 759                                    char *buffer, loff_t offset, size_t count)
 760 {
 761         struct device *dev = kobj_to_dev(kobj);
 762         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 763         struct firmware_buf *buf;
 764         ssize_t retval;
 765
 766         if (!capable(CAP_SYS_RAWIO))
 767                 return -EPERM;
 768
 769         mutex_lock(&fw_lock);
 770         buf = fw_priv->buf;
 771         if (!buf || test_bit(FW_STATUS_DONE, &buf->status)) {
 772                 retval = -ENODEV;
 773                 goto out;
 774         }
 775
 776         retval = fw_realloc_buffer(fw_priv, offset + count);
 777         if (retval)
 778                 goto out;
 779
 780         retval = count;
 781
 782         while (count) {
 783                 void *page_data;
 784                 int page_nr = offset >> PAGE_SHIFT;
 785                 int page_ofs = offset & (PAGE_SIZE - 1);
 786                 int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
 787
 788                 page_data = kmap(buf->pages[page_nr]);
 789
 790                 memcpy(page_data + page_ofs, buffer, page_cnt);
 791
 792                 kunmap(buf->pages[page_nr]);
 793                 buffer += page_cnt;
 794                 offset += page_cnt;
 795                 count -= page_cnt;
 796         }
 797
 798         buf->size = max_t(size_t, offset, buf->size);
 799 out:
 800         mutex_unlock(&fw_lock);
 801         return retval;
 802 }
 803
 804 static struct bin_attribute firmware_attr_data = {
 805         .attr = { .name = "data", .mode = 0644 },
 806         .size = 0,
 807         .read = firmware_data_read,
 808         .write = firmware_data_write,
 809 };
 810
 811 static void firmware_class_timeout_work(struct work_struct *work)
 812 {
 813         struct firmware_priv *fw_priv = container_of(work,
 814                         struct firmware_priv, timeout_work.work);
 815
 816         mutex_lock(&fw_lock);
 817         fw_load_abort(fw_priv);
 818         mutex_unlock(&fw_lock);
 819 }
 820
 821 static struct firmware_priv *
 822 fw_create_instance(struct firmware *firmware, const char *fw_name,
 823                    struct device *device, bool uevent, bool nowait)
 824 {
 825         struct firmware_priv *fw_priv;
 826         struct device *f_dev;
 827
 828         fw_priv = kzalloc(sizeof(*fw_priv), GFP_KERNEL);
 829         if (!fw_priv) {
 830                 dev_err(device, "%s: kmalloc failed\n", __func__);
 831                 fw_priv = ERR_PTR(-ENOMEM);
 832                 goto exit;
 833         }
 834
 835         fw_priv->nowait = nowait;
 836         fw_priv->fw = firmware;
 837         INIT_DELAYED_WORK(&fw_priv->timeout_work,
 838                 firmware_class_timeout_work);
 839
 840         f_dev = &fw_priv->dev;
 841
 842         device_initialize(f_dev);
 843         dev_set_name(f_dev, "%s", fw_name);
 844         f_dev->parent = device;
 845         f_dev->class = &firmware_class;
 846 exit:
 847         return fw_priv;
 848 }
 849
 850 /* load a firmware via user helper */
 851 static int _request_firmware_load(struct firmware_priv *fw_priv, bool uevent,
 852                                   long timeout)
 853 {
 854         int retval = 0;
 855         struct device *f_dev = &fw_priv->dev;
 856         struct firmware_buf *buf = fw_priv->buf;
 857
 858         /* fall back on userspace loading */
 859         buf->is_paged_buf = true;
 860
 861         dev_set_uevent_suppress(f_dev, true);
 862
 863         retval = device_add(f_dev);
 864         if (retval) {
 865                 dev_err(f_dev, "%s: device_register failed\n", __func__);
 866                 goto err_put_dev;
 867         }
 868
 869         retval = device_create_bin_file(f_dev, &firmware_attr_data);
 870         if (retval) {
 871                 dev_err(f_dev, "%s: sysfs_create_bin_file failed\n", __func__);
 872                 goto err_del_dev;
 873         }
 874
 875         mutex_lock(&fw_lock);
 876         list_add(&buf->pending_list, &pending_fw_head);
 877         mutex_unlock(&fw_lock);
 878
 879         retval = device_create_file(f_dev, &dev_attr_loading);
 880         if (retval) {
 881                 mutex_lock(&fw_lock);
 882                 list_del_init(&buf->pending_list);
 883                 mutex_unlock(&fw_lock);
 884                 dev_err(f_dev, "%s: device_create_file failed\n", __func__);
 885                 goto err_del_bin_attr;
 886         }
 887
 888         if (uevent) {
 889                 buf->need_uevent = true;
 890                 dev_set_uevent_suppress(f_dev, false);
 891                 dev_dbg(f_dev, "firmware: requesting %s\n", buf->fw_id);
 892                 if (timeout != MAX_SCHEDULE_TIMEOUT)
 893                         schedule_delayed_work(&fw_priv->timeout_work, timeout);
 894
 895                 kobject_uevent(&fw_priv->dev.kobj, KOBJ_ADD);
 896         }
 897
 898         wait_for_completion(&buf->completion);
 899
 900         cancel_delayed_work_sync(&fw_priv->timeout_work);
 901
 902         device_remove_file(f_dev, &dev_attr_loading);
 903 err_del_bin_attr:
 904         device_remove_bin_file(f_dev, &firmware_attr_data);
 905 err_del_dev:
 906         device_del(f_dev);
 907 err_put_dev:
 908         put_device(f_dev);
 909         return retval;
 910 }
 911
 912 static int fw_load_from_user_helper(struct firmware *firmware,
 913                                     const char *name, struct device *device,
 914                                     bool uevent, bool nowait, long timeout)
 915 {
 916         struct firmware_priv *fw_priv;
 917
 918         fw_priv = fw_create_instance(firmware, name, device, uevent, nowait);
 919         if (IS_ERR(fw_priv))
 920                 return PTR_ERR(fw_priv);
 921
 922         fw_priv->buf = firmware->priv;
 923         return _request_firmware_load(fw_priv, uevent, timeout);
 924 }
 925
 926 #ifdef CONFIG_PM_SLEEP
 927 /* kill pending requests without uevent to avoid blocking suspend */
 928 static void kill_requests_without_uevent(void)
 929 {
 930         struct firmware_buf *buf;
 931         struct firmware_buf *next;
 932
 933         mutex_lock(&fw_lock);
 934         list_for_each_entry_safe(buf, next, &pending_fw_head, pending_list) {
 935                 if (!buf->need_uevent)
 936                          __fw_load_abort(buf);
 937         }
 938         mutex_unlock(&fw_lock);
 939 }
 940 #endif
 941
 942 #else /* CONFIG_FW_LOADER_USER_HELPER */
 943 static inline int
 944 fw_load_from_user_helper(struct firmware *firmware, const char *name,
 945                          struct device *device, bool uevent, bool nowait,
 946                          long timeout)
 947 {
 948         return -ENOENT;
 949 }
 950
 951 /* No abort during direct loading */
 952 #define is_fw_load_aborted(buf) false
 953
 954 #ifdef CONFIG_PM_SLEEP
 955 static inline void kill_requests_without_uevent(void) { }
 956 #endif
 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                                 bool skip_cache)
1027 {
1028         struct firmware_buf *buf = fw->priv;
1029
1030         mutex_lock(&fw_lock);
1031         if (!buf->size || is_fw_load_aborted(buf)) {
1032                 mutex_unlock(&fw_lock);
1033                 return -ENOENT;
1034         }
1035
1036         /*
1037          * add firmware name into devres list so that we can auto cache
1038          * and uncache firmware for device.
1039          *
1040          * device may has been deleted already, but the problem
1041          * should be fixed in devres or driver core.
1042          */
1043         if (device && !skip_cache)
1044                 fw_add_devm_name(device, buf->fw_id);
1045
1046         /*
1047          * After caching firmware image is started, let it piggyback
1048          * on request firmware.
1049          */
1050         if (buf->fwc->state == FW_LOADER_START_CACHE) {
1051                 if (fw_cache_piggyback_on_request(buf->fw_id))
1052                         kref_get(&buf->ref);
1053         }
1054
1055         /* pass the pages buffer to driver at the last minute */
1056         fw_set_page_data(buf, fw);
1057         mutex_unlock(&fw_lock);
1058         return 0;
1059 }
1060
1061 /* called from request_firmware() and request_firmware_work_func() */
1062 static int
1063 _request_firmware(const struct firmware **firmware_p, const char *name,
1064                   struct device *device, bool uevent, bool nowait)
1065 {
1066         struct firmware *fw;
1067         long timeout;
1068         int ret;
1069
1070         if (!firmware_p)
1071                 return -EINVAL;
1072
1073         ret = _request_firmware_prepare(&fw, name, device);
1074         if (ret <= 0) /* error or already assigned */
1075                 goto out;
1076
1077         ret = 0;
1078         timeout = firmware_loading_timeout();
1079         if (nowait) {
1080                 timeout = usermodehelper_read_lock_wait(timeout);
1081                 if (!timeout) {
1082                         dev_dbg(device, "firmware: %s loading timed out\n",
1083                                 name);
1084                         ret = -EBUSY;
1085                         goto out;
1086                 }
1087         } else {
1088                 ret = usermodehelper_read_trylock();
1089                 if (WARN_ON(ret)) {
1090                         dev_err(device, "firmware: %s will not be loaded\n",
1091                                 name);
1092                         goto out;
1093                 }
1094         }
1095
1096         ret = fw_get_filesystem_firmware(device, fw->priv);
1097         if (ret) {
1098                 dev_warn(device, "Direct firmware load failed with error %d\n",
1099                          ret);
1100                 dev_warn(device, "Falling back to user helper\n");
1101                 ret = fw_load_from_user_helper(fw, name, device,
1102                                                uevent, nowait, timeout);
1103         }
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 #ifdef CONFIG_PM_SLEEP
1251 static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
1252
1253 /**
1254  * cache_firmware - cache one firmware image in kernel memory space
1255  * @fw_name: the firmware image name
1256  *
1257  * Cache firmware in kernel memory so that drivers can use it when
1258  * system isn't ready for them to request firmware image from userspace.
1259  * Once it returns successfully, driver can use request_firmware or its
1260  * nowait version to get the cached firmware without any interacting
1261  * with userspace
1262  *
1263  * Return 0 if the firmware image has been cached successfully
1264  * Return !0 otherwise
1265  *
1266  */
1267 static int cache_firmware(const char *fw_name)
1268 {
1269         int ret;
1270         const struct firmware *fw;
1271
1272         pr_debug("%s: %s\n", __func__, fw_name);
1273
1274         ret = request_firmware(&fw, fw_name, NULL);
1275         if (!ret)
1276                 kfree(fw);
1277
1278         pr_debug("%s: %s ret=%d\n", __func__, fw_name, ret);
1279
1280         return ret;
1281 }
1282
1283 static struct firmware_buf *fw_lookup_buf(const char *fw_name)
1284 {
1285         struct firmware_buf *tmp;
1286         struct firmware_cache *fwc = &fw_cache;
1287
1288         spin_lock(&fwc->lock);
1289         tmp = __fw_lookup_buf(fw_name);
1290         spin_unlock(&fwc->lock);
1291
1292         return tmp;
1293 }
1294
1295 /**
1296  * uncache_firmware - remove one cached firmware image
1297  * @fw_name: the firmware image name
1298  *
1299  * Uncache one firmware image which has been cached successfully
1300  * before.
1301  *
1302  * Return 0 if the firmware cache has been removed successfully
1303  * Return !0 otherwise
1304  *
1305  */
1306 static int uncache_firmware(const char *fw_name)
1307 {
1308         struct firmware_buf *buf;
1309         struct firmware fw;
1310
1311         pr_debug("%s: %s\n", __func__, fw_name);
1312
1313         if (fw_get_builtin_firmware(&fw, fw_name))
1314                 return 0;
1315
1316         buf = fw_lookup_buf(fw_name);
1317         if (buf) {
1318                 fw_free_buf(buf);
1319                 return 0;
1320         }
1321
1322         return -EINVAL;
1323 }
1324
1325 static struct fw_cache_entry *alloc_fw_cache_entry(const char *name)
1326 {
1327         struct fw_cache_entry *fce;
1328
1329         fce = kzalloc(sizeof(*fce) + strlen(name) + 1, GFP_ATOMIC);
1330         if (!fce)
1331                 goto exit;
1332
1333         strcpy(fce->name, name);
1334 exit:
1335         return fce;
1336 }
1337
1338 static int __fw_entry_found(const char *name)
1339 {
1340         struct firmware_cache *fwc = &fw_cache;
1341         struct fw_cache_entry *fce;
1342
1343         list_for_each_entry(fce, &fwc->fw_names, list) {
1344                 if (!strcmp(fce->name, name))
1345                         return 1;
1346         }
1347         return 0;
1348 }
1349
1350 static int fw_cache_piggyback_on_request(const char *name)
1351 {
1352         struct firmware_cache *fwc = &fw_cache;
1353         struct fw_cache_entry *fce;
1354         int ret = 0;
1355
1356         spin_lock(&fwc->name_lock);
1357         if (__fw_entry_found(name))
1358                 goto found;
1359
1360         fce = alloc_fw_cache_entry(name);
1361         if (fce) {
1362                 ret = 1;
1363                 list_add(&fce->list, &fwc->fw_names);
1364                 pr_debug("%s: fw: %s\n", __func__, name);
1365         }
1366 found:
1367         spin_unlock(&fwc->name_lock);
1368         return ret;
1369 }
1370
1371 static void free_fw_cache_entry(struct fw_cache_entry *fce)
1372 {
1373         kfree(fce);
1374 }
1375
1376 static void __async_dev_cache_fw_image(void *fw_entry,
1377                                        async_cookie_t cookie)
1378 {
1379         struct fw_cache_entry *fce = fw_entry;
1380         struct firmware_cache *fwc = &fw_cache;
1381         int ret;
1382
1383         ret = cache_firmware(fce->name);
1384         if (ret) {
1385                 spin_lock(&fwc->name_lock);
1386                 list_del(&fce->list);
1387                 spin_unlock(&fwc->name_lock);
1388
1389                 free_fw_cache_entry(fce);
1390         }
1391 }
1392
1393 /* called with dev->devres_lock held */
1394 static void dev_create_fw_entry(struct device *dev, void *res,
1395                                 void *data)
1396 {
1397         struct fw_name_devm *fwn = res;
1398         const char *fw_name = fwn->name;
1399         struct list_head *head = data;
1400         struct fw_cache_entry *fce;
1401
1402         fce = alloc_fw_cache_entry(fw_name);
1403         if (fce)
1404                 list_add(&fce->list, head);
1405 }
1406
1407 static int devm_name_match(struct device *dev, void *res,
1408                            void *match_data)
1409 {
1410         struct fw_name_devm *fwn = res;
1411         return (fwn->magic == (unsigned long)match_data);
1412 }
1413
1414 static void dev_cache_fw_image(struct device *dev, void *data)
1415 {
1416         LIST_HEAD(todo);
1417         struct fw_cache_entry *fce;
1418         struct fw_cache_entry *fce_next;
1419         struct firmware_cache *fwc = &fw_cache;
1420
1421         devres_for_each_res(dev, fw_name_devm_release,
1422                             devm_name_match, &fw_cache,
1423                             dev_create_fw_entry, &todo);
1424
1425         list_for_each_entry_safe(fce, fce_next, &todo, list) {
1426                 list_del(&fce->list);
1427
1428                 spin_lock(&fwc->name_lock);
1429                 /* only one cache entry for one firmware */
1430                 if (!__fw_entry_found(fce->name)) {
1431                         list_add(&fce->list, &fwc->fw_names);
1432                 } else {
1433                         free_fw_cache_entry(fce);
1434                         fce = NULL;
1435                 }
1436                 spin_unlock(&fwc->name_lock);
1437
1438                 if (fce)
1439                         async_schedule_domain(__async_dev_cache_fw_image,
1440                                               (void *)fce,
1441                                               &fw_cache_domain);
1442         }
1443 }
1444
1445 static void __device_uncache_fw_images(void)
1446 {
1447         struct firmware_cache *fwc = &fw_cache;
1448         struct fw_cache_entry *fce;
1449
1450         spin_lock(&fwc->name_lock);
1451         while (!list_empty(&fwc->fw_names)) {
1452                 fce = list_entry(fwc->fw_names.next,
1453                                 struct fw_cache_entry, list);
1454                 list_del(&fce->list);
1455                 spin_unlock(&fwc->name_lock);
1456
1457                 uncache_firmware(fce->name);
1458                 free_fw_cache_entry(fce);
1459
1460                 spin_lock(&fwc->name_lock);
1461         }
1462         spin_unlock(&fwc->name_lock);
1463 }
1464
1465 /**
1466  * device_cache_fw_images - cache devices' firmware
1467  *
1468  * If one device called request_firmware or its nowait version
1469  * successfully before, the firmware names are recored into the
1470  * device's devres link list, so device_cache_fw_images can call
1471  * cache_firmware() to cache these firmwares for the device,
1472  * then the device driver can load its firmwares easily at
1473  * time when system is not ready to complete loading firmware.
1474  */
1475 static void device_cache_fw_images(void)
1476 {
1477         struct firmware_cache *fwc = &fw_cache;
1478         int old_timeout;
1479         DEFINE_WAIT(wait);
1480
1481         pr_debug("%s\n", __func__);
1482
1483         /* cancel uncache work */
1484         cancel_delayed_work_sync(&fwc->work);
1485
1486         /*
1487          * use small loading timeout for caching devices' firmware
1488          * because all these firmware images have been loaded
1489          * successfully at lease once, also system is ready for
1490          * completing firmware loading now. The maximum size of
1491          * firmware in current distributions is about 2M bytes,
1492          * so 10 secs should be enough.
1493          */
1494         old_timeout = loading_timeout;
1495         loading_timeout = 10;
1496
1497         mutex_lock(&fw_lock);
1498         fwc->state = FW_LOADER_START_CACHE;
1499         dpm_for_each_dev(NULL, dev_cache_fw_image);
1500         mutex_unlock(&fw_lock);
1501
1502         /* wait for completion of caching firmware for all devices */
1503         async_synchronize_full_domain(&fw_cache_domain);
1504
1505         loading_timeout = old_timeout;
1506 }
1507
1508 /**
1509  * device_uncache_fw_images - uncache devices' firmware
1510  *
1511  * uncache all firmwares which have been cached successfully
1512  * by device_uncache_fw_images earlier
1513  */
1514 static void device_uncache_fw_images(void)
1515 {
1516         pr_debug("%s\n", __func__);
1517         __device_uncache_fw_images();
1518 }
1519
1520 static void device_uncache_fw_images_work(struct work_struct *work)
1521 {
1522         device_uncache_fw_images();
1523 }
1524
1525 /**
1526  * device_uncache_fw_images_delay - uncache devices firmwares
1527  * @delay: number of milliseconds to delay uncache device firmwares
1528  *
1529  * uncache all devices's firmwares which has been cached successfully
1530  * by device_cache_fw_images after @delay milliseconds.
1531  */
1532 static void device_uncache_fw_images_delay(unsigned long delay)
1533 {
1534         schedule_delayed_work(&fw_cache.work,
1535                         msecs_to_jiffies(delay));
1536 }
1537
1538 static int fw_pm_notify(struct notifier_block *notify_block,
1539                         unsigned long mode, void *unused)
1540 {
1541         switch (mode) {
1542         case PM_HIBERNATION_PREPARE:
1543         case PM_SUSPEND_PREPARE:
1544                 kill_requests_without_uevent();
1545                 device_cache_fw_images();
1546                 break;
1547
1548         case PM_POST_SUSPEND:
1549         case PM_POST_HIBERNATION:
1550         case PM_POST_RESTORE:
1551                 /*
1552                  * In case that system sleep failed and syscore_suspend is
1553                  * not called.
1554                  */
1555                 mutex_lock(&fw_lock);
1556                 fw_cache.state = FW_LOADER_NO_CACHE;
1557                 mutex_unlock(&fw_lock);
1558
1559                 device_uncache_fw_images_delay(10 * MSEC_PER_SEC);
1560                 break;
1561         }
1562
1563         return 0;
1564 }
1565
1566 /* stop caching firmware once syscore_suspend is reached */
1567 static int fw_suspend(void)
1568 {
1569         fw_cache.state = FW_LOADER_NO_CACHE;
1570         return 0;
1571 }
1572
1573 static struct syscore_ops fw_syscore_ops = {
1574         .suspend = fw_suspend,
1575 };
1576 #else
1577 static int fw_cache_piggyback_on_request(const char *name)
1578 {
1579         return 0;
1580 }
1581 #endif
1582
1583 static void __init fw_cache_init(void)
1584 {
1585         spin_lock_init(&fw_cache.lock);
1586         INIT_LIST_HEAD(&fw_cache.head);
1587         fw_cache.state = FW_LOADER_NO_CACHE;
1588
1589 #ifdef CONFIG_PM_SLEEP
1590         spin_lock_init(&fw_cache.name_lock);
1591         INIT_LIST_HEAD(&fw_cache.fw_names);
1592
1593         INIT_DELAYED_WORK(&fw_cache.work,
1594                           device_uncache_fw_images_work);
1595
1596         fw_cache.pm_notify.notifier_call = fw_pm_notify;
1597         register_pm_notifier(&fw_cache.pm_notify);
1598
1599         register_syscore_ops(&fw_syscore_ops);
1600 #endif
1601 }
1602
1603 static int __init firmware_class_init(void)
1604 {
1605         fw_cache_init();
1606 #ifdef CONFIG_FW_LOADER_USER_HELPER
1607         register_reboot_notifier(&fw_shutdown_nb);
1608         return class_register(&firmware_class);
1609 #else
1610         return 0;
1611 #endif
1612 }
1613
1614 static void __exit firmware_class_exit(void)
1615 {
1616 #ifdef CONFIG_PM_SLEEP
1617         unregister_syscore_ops(&fw_syscore_ops);
1618         unregister_pm_notifier(&fw_cache.pm_notify);
1619 #endif
1620 #ifdef CONFIG_FW_LOADER_USER_HELPER
1621         unregister_reboot_notifier(&fw_shutdown_nb);
1622         class_unregister(&firmware_class);
1623 #endif
1624 }
1625
1626 fs_initcall(firmware_class_init);
1627 module_exit(firmware_class_exit);