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 #include <linux/security.h>
  32
  33 #include <generated/utsrelease.h>
  34
  35 #include "base.h"
  36
  37 MODULE_AUTHOR("Manuel Estrada Sainz");
  38 MODULE_DESCRIPTION("Multi purpose firmware loading support");
  39 MODULE_LICENSE("GPL");
  40
  41 /* Builtin firmware support */
  42
  43 #ifdef CONFIG_FW_LOADER
  44
  45 extern struct builtin_fw __start_builtin_fw[];
  46 extern struct builtin_fw __end_builtin_fw[];
  47
  48 static bool fw_get_builtin_firmware(struct firmware *fw, const char *name)
  49 {
  50         struct builtin_fw *b_fw;
  51
  52         for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++) {
  53                 if (strcmp(name, b_fw->name) == 0) {
  54                         fw->size = b_fw->size;
  55                         fw->data = b_fw->data;
  56                         return true;
  57                 }
  58         }
  59
  60         return false;
  61 }
  62
  63 static bool fw_is_builtin_firmware(const struct firmware *fw)
  64 {
  65         struct builtin_fw *b_fw;
  66
  67         for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++)
  68                 if (fw->data == b_fw->data)
  69                         return true;
  70
  71         return false;
  72 }
  73
  74 #else /* Module case - no builtin firmware support */
  75
  76 static inline bool fw_get_builtin_firmware(struct firmware *fw, const char *name)
  77 {
  78         return false;
  79 }
  80
  81 static inline bool fw_is_builtin_firmware(const struct firmware *fw)
  82 {
  83         return false;
  84 }
  85 #endif
  86
  87 enum {
  88         FW_STATUS_LOADING,
  89         FW_STATUS_DONE,
  90         FW_STATUS_ABORT,
  91 };
  92
  93 static int loading_timeout = 60;        /* In seconds */
  94
  95 static inline long firmware_loading_timeout(void)
  96 {
  97         return loading_timeout > 0 ? loading_timeout * HZ : MAX_SCHEDULE_TIMEOUT;
  98 }
  99
 100 /* firmware behavior options */
 101 #define FW_OPT_UEVENT   (1U << 0)
 102 #define FW_OPT_NOWAIT   (1U << 1)
 103 #ifdef CONFIG_FW_LOADER_USER_HELPER
 104 #define FW_OPT_USERHELPER       (1U << 2)
 105 #else
 106 #define FW_OPT_USERHELPER       0
 107 #endif
 108 #ifdef CONFIG_FW_LOADER_USER_HELPER_FALLBACK
 109 #define FW_OPT_FALLBACK         FW_OPT_USERHELPER
 110 #else
 111 #define FW_OPT_FALLBACK         0
 112 #endif
 113 #define FW_OPT_NO_WARN  (1U << 3)
 114
 115 struct firmware_cache {
 116         /* firmware_buf instance will be added into the below list */
 117         spinlock_t lock;
 118         struct list_head head;
 119         int state;
 120
 121 #ifdef CONFIG_PM_SLEEP
 122         /*
 123          * Names of firmware images which have been cached successfully
 124          * will be added into the below list so that device uncache
 125          * helper can trace which firmware images have been cached
 126          * before.
 127          */
 128         spinlock_t name_lock;
 129         struct list_head fw_names;
 130
 131         struct delayed_work work;
 132
 133         struct notifier_block   pm_notify;
 134 #endif
 135 };
 136
 137 struct firmware_buf {
 138         struct kref ref;
 139         struct list_head list;
 140         struct completion completion;
 141         struct firmware_cache *fwc;
 142         unsigned long status;
 143         void *data;
 144         size_t size;
 145 #ifdef CONFIG_FW_LOADER_USER_HELPER
 146         bool is_paged_buf;
 147         bool need_uevent;
 148         struct page **pages;
 149         int nr_pages;
 150         int page_array_size;
 151         struct list_head pending_list;
 152 #endif
 153         char fw_id[];
 154 };
 155
 156 struct fw_cache_entry {
 157         struct list_head list;
 158         char name[];
 159 };
 160
 161 struct fw_name_devm {
 162         unsigned long magic;
 163         char name[];
 164 };
 165
 166 #define to_fwbuf(d) container_of(d, struct firmware_buf, ref)
 167
 168 #define FW_LOADER_NO_CACHE      0
 169 #define FW_LOADER_START_CACHE   1
 170
 171 static int fw_cache_piggyback_on_request(const char *name);
 172
 173 /* fw_lock could be moved to 'struct firmware_priv' but since it is just
 174  * guarding for corner cases a global lock should be OK */
 175 static DEFINE_MUTEX(fw_lock);
 176
 177 static struct firmware_cache fw_cache;
 178
 179 static struct firmware_buf *__allocate_fw_buf(const char *fw_name,
 180                                               struct firmware_cache *fwc)
 181 {
 182         struct firmware_buf *buf;
 183
 184         buf = kzalloc(sizeof(*buf) + strlen(fw_name) + 1 , GFP_ATOMIC);
 185
 186         if (!buf)
 187                 return buf;
 188
 189         kref_init(&buf->ref);
 190         strcpy(buf->fw_id, fw_name);
 191         buf->fwc = fwc;
 192         init_completion(&buf->completion);
 193 #ifdef CONFIG_FW_LOADER_USER_HELPER
 194         INIT_LIST_HEAD(&buf->pending_list);
 195 #endif
 196
 197         pr_debug("%s: fw-%s buf=%p\n", __func__, fw_name, buf);
 198
 199         return buf;
 200 }
 201
 202 static struct firmware_buf *__fw_lookup_buf(const char *fw_name)
 203 {
 204         struct firmware_buf *tmp;
 205         struct firmware_cache *fwc = &fw_cache;
 206
 207         list_for_each_entry(tmp, &fwc->head, list)
 208                 if (!strcmp(tmp->fw_id, fw_name))
 209                         return tmp;
 210         return NULL;
 211 }
 212
 213 static int fw_lookup_and_allocate_buf(const char *fw_name,
 214                                       struct firmware_cache *fwc,
 215                                       struct firmware_buf **buf)
 216 {
 217         struct firmware_buf *tmp;
 218
 219         spin_lock(&fwc->lock);
 220         tmp = __fw_lookup_buf(fw_name);
 221         if (tmp) {
 222                 kref_get(&tmp->ref);
 223                 spin_unlock(&fwc->lock);
 224                 *buf = tmp;
 225                 return 1;
 226         }
 227         tmp = __allocate_fw_buf(fw_name, fwc);
 228         if (tmp)
 229                 list_add(&tmp->list, &fwc->head);
 230         spin_unlock(&fwc->lock);
 231
 232         *buf = tmp;
 233
 234         return tmp ? 0 : -ENOMEM;
 235 }
 236
 237 static void __fw_free_buf(struct kref *ref)
 238         __releases(&fwc->lock)
 239 {
 240         struct firmware_buf *buf = to_fwbuf(ref);
 241         struct firmware_cache *fwc = buf->fwc;
 242
 243         pr_debug("%s: fw-%s buf=%p data=%p size=%u\n",
 244                  __func__, buf->fw_id, buf, buf->data,
 245                  (unsigned int)buf->size);
 246
 247         list_del(&buf->list);
 248         spin_unlock(&fwc->lock);
 249
 250 #ifdef CONFIG_FW_LOADER_USER_HELPER
 251         if (buf->is_paged_buf) {
 252                 int i;
 253                 vunmap(buf->data);
 254                 for (i = 0; i < buf->nr_pages; i++)
 255                         __free_page(buf->pages[i]);
 256                 kfree(buf->pages);
 257         } else
 258 #endif
 259                 vfree(buf->data);
 260         kfree(buf);
 261 }
 262
 263 static void fw_free_buf(struct firmware_buf *buf)
 264 {
 265         struct firmware_cache *fwc = buf->fwc;
 266         spin_lock(&fwc->lock);
 267         if (!kref_put(&buf->ref, __fw_free_buf))
 268                 spin_unlock(&fwc->lock);
 269 }
 270
 271 /* direct firmware loading support */
 272 static char fw_path_para[256];
 273 static const char * const fw_path[] = {
 274         fw_path_para,
 275         "/lib/firmware/updates/" UTS_RELEASE,
 276         "/lib/firmware/updates",
 277         "/lib/firmware/" UTS_RELEASE,
 278         "/lib/firmware"
 279 };
 280
 281 /*
 282  * Typical usage is that passing 'firmware_class.path=$CUSTOMIZED_PATH'
 283  * from kernel command line because firmware_class is generally built in
 284  * kernel instead of module.
 285  */
 286 module_param_string(path, fw_path_para, sizeof(fw_path_para), 0644);
 287 MODULE_PARM_DESC(path, "customized firmware image search path with a higher priority than default path");
 288
 289 static int fw_read_file_contents(struct file *file, struct firmware_buf *fw_buf)
 290 {
 291         int size;
 292         char *buf;
 293         int rc;
 294
 295         if (!S_ISREG(file_inode(file)->i_mode))
 296                 return -EINVAL;
 297         size = i_size_read(file_inode(file));
 298         if (size <= 0)
 299                 return -EINVAL;
 300         buf = vmalloc(size);
 301         if (!buf)
 302                 return -ENOMEM;
 303         rc = kernel_read(file, 0, buf, size);
 304         if (rc != size) {
 305                 if (rc > 0)
 306                         rc = -EIO;
 307                 goto fail;
 308         }
 309         rc = security_kernel_fw_from_file(file, buf, size);
 310         if (rc)
 311                 goto fail;
 312         fw_buf->data = buf;
 313         fw_buf->size = size;
 314         return 0;
 315 fail:
 316         vfree(buf);
 317         return rc;
 318 }
 319
 320 static int fw_get_filesystem_firmware(struct device *device,
 321                                        struct firmware_buf *buf)
 322 {
 323         int i;
 324         int rc = -ENOENT;
 325         char *path = __getname();
 326
 327         for (i = 0; i < ARRAY_SIZE(fw_path); i++) {
 328                 struct file *file;
 329
 330                 /* skip the unset customized path */
 331                 if (!fw_path[i][0])
 332                         continue;
 333
 334                 snprintf(path, PATH_MAX, "%s/%s", fw_path[i], buf->fw_id);
 335
 336                 file = filp_open(path, O_RDONLY, 0);
 337                 if (IS_ERR(file))
 338                         continue;
 339                 rc = fw_read_file_contents(file, buf);
 340                 fput(file);
 341                 if (rc)
 342                         dev_warn(device, "firmware, attempted to load %s, but failed with error %d\n",
 343                                 path, rc);
 344                 else
 345                         break;
 346         }
 347         __putname(path);
 348
 349         if (!rc) {
 350                 dev_dbg(device, "firmware: direct-loading firmware %s\n",
 351                         buf->fw_id);
 352                 mutex_lock(&fw_lock);
 353                 set_bit(FW_STATUS_DONE, &buf->status);
 354                 complete_all(&buf->completion);
 355                 mutex_unlock(&fw_lock);
 356         }
 357
 358         return rc;
 359 }
 360
 361 /* firmware holds the ownership of pages */
 362 static void firmware_free_data(const struct firmware *fw)
 363 {
 364         /* Loaded directly? */
 365         if (!fw->priv) {
 366                 vfree(fw->data);
 367                 return;
 368         }
 369         fw_free_buf(fw->priv);
 370 }
 371
 372 /* store the pages buffer info firmware from buf */
 373 static void fw_set_page_data(struct firmware_buf *buf, struct firmware *fw)
 374 {
 375         fw->priv = buf;
 376 #ifdef CONFIG_FW_LOADER_USER_HELPER
 377         fw->pages = buf->pages;
 378 #endif
 379         fw->size = buf->size;
 380         fw->data = buf->data;
 381
 382         pr_debug("%s: fw-%s buf=%p data=%p size=%u\n",
 383                  __func__, buf->fw_id, buf, buf->data,
 384                  (unsigned int)buf->size);
 385 }
 386
 387 #ifdef CONFIG_PM_SLEEP
 388 static void fw_name_devm_release(struct device *dev, void *res)
 389 {
 390         struct fw_name_devm *fwn = res;
 391
 392         if (fwn->magic == (unsigned long)&fw_cache)
 393                 pr_debug("%s: fw_name-%s devm-%p released\n",
 394                                 __func__, fwn->name, res);
 395 }
 396
 397 static int fw_devm_match(struct device *dev, void *res,
 398                 void *match_data)
 399 {
 400         struct fw_name_devm *fwn = res;
 401
 402         return (fwn->magic == (unsigned long)&fw_cache) &&
 403                 !strcmp(fwn->name, match_data);
 404 }
 405
 406 static struct fw_name_devm *fw_find_devm_name(struct device *dev,
 407                 const char *name)
 408 {
 409         struct fw_name_devm *fwn;
 410
 411         fwn = devres_find(dev, fw_name_devm_release,
 412                           fw_devm_match, (void *)name);
 413         return fwn;
 414 }
 415
 416 /* add firmware name into devres list */
 417 static int fw_add_devm_name(struct device *dev, const char *name)
 418 {
 419         struct fw_name_devm *fwn;
 420
 421         fwn = fw_find_devm_name(dev, name);
 422         if (fwn)
 423                 return 1;
 424
 425         fwn = devres_alloc(fw_name_devm_release, sizeof(struct fw_name_devm) +
 426                            strlen(name) + 1, GFP_KERNEL);
 427         if (!fwn)
 428                 return -ENOMEM;
 429
 430         fwn->magic = (unsigned long)&fw_cache;
 431         strcpy(fwn->name, name);
 432         devres_add(dev, fwn);
 433
 434         return 0;
 435 }
 436 #else
 437 static int fw_add_devm_name(struct device *dev, const char *name)
 438 {
 439         return 0;
 440 }
 441 #endif
 442
 443
 444 /*
 445  * user-mode helper code
 446  */
 447 #ifdef CONFIG_FW_LOADER_USER_HELPER
 448 struct firmware_priv {
 449         struct delayed_work timeout_work;
 450         bool nowait;
 451         struct device dev;
 452         struct firmware_buf *buf;
 453         struct firmware *fw;
 454 };
 455
 456 static struct firmware_priv *to_firmware_priv(struct device *dev)
 457 {
 458         return container_of(dev, struct firmware_priv, dev);
 459 }
 460
 461 static void __fw_load_abort(struct firmware_buf *buf)
 462 {
 463         /*
 464          * There is a small window in which user can write to 'loading'
 465          * between loading done and disappearance of 'loading'
 466          */
 467         if (test_bit(FW_STATUS_DONE, &buf->status))
 468                 return;
 469
 470         list_del_init(&buf->pending_list);
 471         set_bit(FW_STATUS_ABORT, &buf->status);
 472         complete_all(&buf->completion);
 473 }
 474
 475 static void fw_load_abort(struct firmware_priv *fw_priv)
 476 {
 477         struct firmware_buf *buf = fw_priv->buf;
 478
 479         __fw_load_abort(buf);
 480
 481         /* avoid user action after loading abort */
 482         fw_priv->buf = NULL;
 483 }
 484
 485 #define is_fw_load_aborted(buf) \
 486         test_bit(FW_STATUS_ABORT, &(buf)->status)
 487
 488 static LIST_HEAD(pending_fw_head);
 489
 490 /* reboot notifier for avoid deadlock with usermode_lock */
 491 static int fw_shutdown_notify(struct notifier_block *unused1,
 492                               unsigned long unused2, void *unused3)
 493 {
 494         mutex_lock(&fw_lock);
 495         while (!list_empty(&pending_fw_head))
 496                 __fw_load_abort(list_first_entry(&pending_fw_head,
 497                                                struct firmware_buf,
 498                                                pending_list));
 499         mutex_unlock(&fw_lock);
 500         return NOTIFY_DONE;
 501 }
 502
 503 static struct notifier_block fw_shutdown_nb = {
 504         .notifier_call = fw_shutdown_notify,
 505 };
 506
 507 static ssize_t timeout_show(struct class *class, struct class_attribute *attr,
 508                             char *buf)
 509 {
 510         return sprintf(buf, "%d\n", loading_timeout);
 511 }
 512
 513 /**
 514  * firmware_timeout_store - set number of seconds to wait for firmware
 515  * @class: device class pointer
 516  * @attr: device attribute pointer
 517  * @buf: buffer to scan for timeout value
 518  * @count: number of bytes in @buf
 519  *
 520  *      Sets the number of seconds to wait for the firmware.  Once
 521  *      this expires an error will be returned to the driver and no
 522  *      firmware will be provided.
 523  *
 524  *      Note: zero means 'wait forever'.
 525  **/
 526 static ssize_t timeout_store(struct class *class, struct class_attribute *attr,
 527                              const char *buf, size_t count)
 528 {
 529         loading_timeout = simple_strtol(buf, NULL, 10);
 530         if (loading_timeout < 0)
 531                 loading_timeout = 0;
 532
 533         return count;
 534 }
 535
 536 static struct class_attribute firmware_class_attrs[] = {
 537         __ATTR_RW(timeout),
 538         __ATTR_NULL
 539 };
 540
 541 static void fw_dev_release(struct device *dev)
 542 {
 543         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 544
 545         kfree(fw_priv);
 546 }
 547
 548 static int firmware_uevent(struct device *dev, struct kobj_uevent_env *env)
 549 {
 550         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 551
 552         if (add_uevent_var(env, "FIRMWARE=%s", fw_priv->buf->fw_id))
 553                 return -ENOMEM;
 554         if (add_uevent_var(env, "TIMEOUT=%i", loading_timeout))
 555                 return -ENOMEM;
 556         if (add_uevent_var(env, "ASYNC=%d", fw_priv->nowait))
 557                 return -ENOMEM;
 558
 559         return 0;
 560 }
 561
 562 static struct class firmware_class = {
 563         .name           = "firmware",
 564         .class_attrs    = firmware_class_attrs,
 565         .dev_uevent     = firmware_uevent,
 566         .dev_release    = fw_dev_release,
 567 };
 568
 569 static ssize_t firmware_loading_show(struct device *dev,
 570                                      struct device_attribute *attr, char *buf)
 571 {
 572         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 573         int loading = 0;
 574
 575         mutex_lock(&fw_lock);
 576         if (fw_priv->buf)
 577                 loading = test_bit(FW_STATUS_LOADING, &fw_priv->buf->status);
 578         mutex_unlock(&fw_lock);
 579
 580         return sprintf(buf, "%d\n", loading);
 581 }
 582
 583 /* Some architectures don't have PAGE_KERNEL_RO */
 584 #ifndef PAGE_KERNEL_RO
 585 #define PAGE_KERNEL_RO PAGE_KERNEL
 586 #endif
 587
 588 /* one pages buffer should be mapped/unmapped only once */
 589 static int fw_map_pages_buf(struct firmware_buf *buf)
 590 {
 591         if (!buf->is_paged_buf)
 592                 return 0;
 593
 594         vunmap(buf->data);
 595         buf->data = vmap(buf->pages, buf->nr_pages, 0, PAGE_KERNEL_RO);
 596         if (!buf->data)
 597                 return -ENOMEM;
 598         return 0;
 599 }
 600
 601 /**
 602  * firmware_loading_store - set value in the 'loading' control file
 603  * @dev: device pointer
 604  * @attr: device attribute pointer
 605  * @buf: buffer to scan for loading control value
 606  * @count: number of bytes in @buf
 607  *
 608  *      The relevant values are:
 609  *
 610  *       1: Start a load, discarding any previous partial load.
 611  *       0: Conclude the load and hand the data to the driver code.
 612  *      -1: Conclude the load with an error and discard any written data.
 613  **/
 614 static ssize_t firmware_loading_store(struct device *dev,
 615                                       struct device_attribute *attr,
 616                                       const char *buf, size_t count)
 617 {
 618         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 619         struct firmware_buf *fw_buf;
 620         ssize_t written = count;
 621         int loading = simple_strtol(buf, NULL, 10);
 622         int i;
 623
 624         mutex_lock(&fw_lock);
 625         fw_buf = fw_priv->buf;
 626         if (!fw_buf)
 627                 goto out;
 628
 629         switch (loading) {
 630         case 1:
 631                 /* discarding any previous partial load */
 632                 if (!test_bit(FW_STATUS_DONE, &fw_buf->status)) {
 633                         for (i = 0; i < fw_buf->nr_pages; i++)
 634                                 __free_page(fw_buf->pages[i]);
 635                         kfree(fw_buf->pages);
 636                         fw_buf->pages = NULL;
 637                         fw_buf->page_array_size = 0;
 638                         fw_buf->nr_pages = 0;
 639                         set_bit(FW_STATUS_LOADING, &fw_buf->status);
 640                 }
 641                 break;
 642         case 0:
 643                 if (test_bit(FW_STATUS_LOADING, &fw_buf->status)) {
 644                         int rc;
 645
 646                         set_bit(FW_STATUS_DONE, &fw_buf->status);
 647                         clear_bit(FW_STATUS_LOADING, &fw_buf->status);
 648
 649                         /*
 650                          * Several loading requests may be pending on
 651                          * one same firmware buf, so let all requests
 652                          * see the mapped 'buf->data' once the loading
 653                          * is completed.
 654                          * */
 655                         rc = fw_map_pages_buf(fw_buf);
 656                         if (rc)
 657                                 dev_err(dev, "%s: map pages failed\n",
 658                                         __func__);
 659                         else
 660                                 rc = security_kernel_fw_from_file(NULL,
 661                                                 fw_buf->data, fw_buf->size);
 662
 663                         /*
 664                          * Same logic as fw_load_abort, only the DONE bit
 665                          * is ignored and we set ABORT only on failure.
 666                          */
 667                         list_del_init(&fw_buf->pending_list);
 668                         if (rc) {
 669                                 set_bit(FW_STATUS_ABORT, &fw_buf->status);
 670                                 written = rc;
 671                         }
 672                         complete_all(&fw_buf->completion);
 673                         break;
 674                 }
 675                 /* fallthrough */
 676         default:
 677                 dev_err(dev, "%s: unexpected value (%d)\n", __func__, loading);
 678                 /* fallthrough */
 679         case -1:
 680                 fw_load_abort(fw_priv);
 681                 break;
 682         }
 683 out:
 684         mutex_unlock(&fw_lock);
 685         return written;
 686 }
 687
 688 static DEVICE_ATTR(loading, 0644, firmware_loading_show, firmware_loading_store);
 689
 690 static ssize_t firmware_data_read(struct file *filp, struct kobject *kobj,
 691                                   struct bin_attribute *bin_attr,
 692                                   char *buffer, loff_t offset, size_t count)
 693 {
 694         struct device *dev = kobj_to_dev(kobj);
 695         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 696         struct firmware_buf *buf;
 697         ssize_t ret_count;
 698
 699         mutex_lock(&fw_lock);
 700         buf = fw_priv->buf;
 701         if (!buf || test_bit(FW_STATUS_DONE, &buf->status)) {
 702                 ret_count = -ENODEV;
 703                 goto out;
 704         }
 705         if (offset > buf->size) {
 706                 ret_count = 0;
 707                 goto out;
 708         }
 709         if (count > buf->size - offset)
 710                 count = buf->size - offset;
 711
 712         ret_count = count;
 713
 714         while (count) {
 715                 void *page_data;
 716                 int page_nr = offset >> PAGE_SHIFT;
 717                 int page_ofs = offset & (PAGE_SIZE-1);
 718                 int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
 719
 720                 page_data = kmap(buf->pages[page_nr]);
 721
 722                 memcpy(buffer, page_data + page_ofs, page_cnt);
 723
 724                 kunmap(buf->pages[page_nr]);
 725                 buffer += page_cnt;
 726                 offset += page_cnt;
 727                 count -= page_cnt;
 728         }
 729 out:
 730         mutex_unlock(&fw_lock);
 731         return ret_count;
 732 }
 733
 734 static int fw_realloc_buffer(struct firmware_priv *fw_priv, int min_size)
 735 {
 736         struct firmware_buf *buf = fw_priv->buf;
 737         int pages_needed = PAGE_ALIGN(min_size) >> PAGE_SHIFT;
 738
 739         /* If the array of pages is too small, grow it... */
 740         if (buf->page_array_size < pages_needed) {
 741                 int new_array_size = max(pages_needed,
 742                                          buf->page_array_size * 2);
 743                 struct page **new_pages;
 744
 745                 new_pages = kmalloc(new_array_size * sizeof(void *),
 746                                     GFP_KERNEL);
 747                 if (!new_pages) {
 748                         fw_load_abort(fw_priv);
 749                         return -ENOMEM;
 750                 }
 751                 memcpy(new_pages, buf->pages,
 752                        buf->page_array_size * sizeof(void *));
 753                 memset(&new_pages[buf->page_array_size], 0, sizeof(void *) *
 754                        (new_array_size - buf->page_array_size));
 755                 kfree(buf->pages);
 756                 buf->pages = new_pages;
 757                 buf->page_array_size = new_array_size;
 758         }
 759
 760         while (buf->nr_pages < pages_needed) {
 761                 buf->pages[buf->nr_pages] =
 762                         alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
 763
 764                 if (!buf->pages[buf->nr_pages]) {
 765                         fw_load_abort(fw_priv);
 766                         return -ENOMEM;
 767                 }
 768                 buf->nr_pages++;
 769         }
 770         return 0;
 771 }
 772
 773 /**
 774  * firmware_data_write - write method for firmware
 775  * @filp: open sysfs file
 776  * @kobj: kobject for the device
 777  * @bin_attr: bin_attr structure
 778  * @buffer: buffer being written
 779  * @offset: buffer offset for write in total data store area
 780  * @count: buffer size
 781  *
 782  *      Data written to the 'data' attribute will be later handed to
 783  *      the driver as a firmware image.
 784  **/
 785 static ssize_t firmware_data_write(struct file *filp, struct kobject *kobj,
 786                                    struct bin_attribute *bin_attr,
 787                                    char *buffer, loff_t offset, size_t count)
 788 {
 789         struct device *dev = kobj_to_dev(kobj);
 790         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 791         struct firmware_buf *buf;
 792         ssize_t retval;
 793
 794         if (!capable(CAP_SYS_RAWIO))
 795                 return -EPERM;
 796
 797         mutex_lock(&fw_lock);
 798         buf = fw_priv->buf;
 799         if (!buf || test_bit(FW_STATUS_DONE, &buf->status)) {
 800                 retval = -ENODEV;
 801                 goto out;
 802         }
 803
 804         retval = fw_realloc_buffer(fw_priv, offset + count);
 805         if (retval)
 806                 goto out;
 807
 808         retval = count;
 809
 810         while (count) {
 811                 void *page_data;
 812                 int page_nr = offset >> PAGE_SHIFT;
 813                 int page_ofs = offset & (PAGE_SIZE - 1);
 814                 int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
 815
 816                 page_data = kmap(buf->pages[page_nr]);
 817
 818                 memcpy(page_data + page_ofs, buffer, page_cnt);
 819
 820                 kunmap(buf->pages[page_nr]);
 821                 buffer += page_cnt;
 822                 offset += page_cnt;
 823                 count -= page_cnt;
 824         }
 825
 826         buf->size = max_t(size_t, offset, buf->size);
 827 out:
 828         mutex_unlock(&fw_lock);
 829         return retval;
 830 }
 831
 832 static struct bin_attribute firmware_attr_data = {
 833         .attr = { .name = "data", .mode = 0644 },
 834         .size = 0,
 835         .read = firmware_data_read,
 836         .write = firmware_data_write,
 837 };
 838
 839 static void firmware_class_timeout_work(struct work_struct *work)
 840 {
 841         struct firmware_priv *fw_priv = container_of(work,
 842                         struct firmware_priv, timeout_work.work);
 843
 844         mutex_lock(&fw_lock);
 845         fw_load_abort(fw_priv);
 846         mutex_unlock(&fw_lock);
 847 }
 848
 849 static struct firmware_priv *
 850 fw_create_instance(struct firmware *firmware, const char *fw_name,
 851                    struct device *device, unsigned int opt_flags)
 852 {
 853         struct firmware_priv *fw_priv;
 854         struct device *f_dev;
 855
 856         fw_priv = kzalloc(sizeof(*fw_priv), GFP_KERNEL);
 857         if (!fw_priv) {
 858                 dev_err(device, "%s: kmalloc failed\n", __func__);
 859                 fw_priv = ERR_PTR(-ENOMEM);
 860                 goto exit;
 861         }
 862
 863         fw_priv->nowait = !!(opt_flags & FW_OPT_NOWAIT);
 864         fw_priv->fw = firmware;
 865         INIT_DELAYED_WORK(&fw_priv->timeout_work,
 866                 firmware_class_timeout_work);
 867
 868         f_dev = &fw_priv->dev;
 869
 870         device_initialize(f_dev);
 871         dev_set_name(f_dev, "%s", fw_name);
 872         f_dev->parent = device;
 873         f_dev->class = &firmware_class;
 874 exit:
 875         return fw_priv;
 876 }
 877
 878 /* load a firmware via user helper */
 879 static int _request_firmware_load(struct firmware_priv *fw_priv,
 880                                   unsigned int opt_flags, long timeout)
 881 {
 882         int retval = 0;
 883         struct device *f_dev = &fw_priv->dev;
 884         struct firmware_buf *buf = fw_priv->buf;
 885
 886         /* fall back on userspace loading */
 887         buf->is_paged_buf = true;
 888
 889         dev_set_uevent_suppress(f_dev, true);
 890
 891         retval = device_add(f_dev);
 892         if (retval) {
 893                 dev_err(f_dev, "%s: device_register failed\n", __func__);
 894                 goto err_put_dev;
 895         }
 896
 897         retval = device_create_bin_file(f_dev, &firmware_attr_data);
 898         if (retval) {
 899                 dev_err(f_dev, "%s: sysfs_create_bin_file failed\n", __func__);
 900                 goto err_del_dev;
 901         }
 902
 903         mutex_lock(&fw_lock);
 904         list_add(&buf->pending_list, &pending_fw_head);
 905         mutex_unlock(&fw_lock);
 906
 907         retval = device_create_file(f_dev, &dev_attr_loading);
 908         if (retval) {
 909                 mutex_lock(&fw_lock);
 910                 list_del_init(&buf->pending_list);
 911                 mutex_unlock(&fw_lock);
 912                 dev_err(f_dev, "%s: device_create_file failed\n", __func__);
 913                 goto err_del_bin_attr;
 914         }
 915
 916         if (opt_flags & FW_OPT_UEVENT) {
 917                 buf->need_uevent = true;
 918                 dev_set_uevent_suppress(f_dev, false);
 919                 dev_dbg(f_dev, "firmware: requesting %s\n", buf->fw_id);
 920                 if (timeout != MAX_SCHEDULE_TIMEOUT)
 921                         queue_delayed_work(system_power_efficient_wq,
 922                                            &fw_priv->timeout_work, timeout);
 923
 924                 kobject_uevent(&fw_priv->dev.kobj, KOBJ_ADD);
 925         }
 926
 927         retval = wait_for_completion_interruptible(&buf->completion);
 928
 929         cancel_delayed_work_sync(&fw_priv->timeout_work);
 930
 931         if (retval == -ERESTARTSYS) {
 932                 mutex_lock(&fw_lock);
 933                 fw_load_abort(fw_priv);
 934                 mutex_unlock(&fw_lock);
 935         }
 936
 937         if (is_fw_load_aborted(buf))
 938                 retval = -EAGAIN;
 939         else if (!buf->data)
 940                 retval = -ENOMEM;
 941
 942         device_remove_file(f_dev, &dev_attr_loading);
 943 err_del_bin_attr:
 944         device_remove_bin_file(f_dev, &firmware_attr_data);
 945 err_del_dev:
 946         device_del(f_dev);
 947 err_put_dev:
 948         put_device(f_dev);
 949         return retval;
 950 }
 951
 952 static int fw_load_from_user_helper(struct firmware *firmware,
 953                                     const char *name, struct device *device,
 954                                     unsigned int opt_flags, long timeout)
 955 {
 956         struct firmware_priv *fw_priv;
 957
 958         fw_priv = fw_create_instance(firmware, name, device, opt_flags);
 959         if (IS_ERR(fw_priv))
 960                 return PTR_ERR(fw_priv);
 961
 962         fw_priv->buf = firmware->priv;
 963         return _request_firmware_load(fw_priv, opt_flags, timeout);
 964 }
 965
 966 #ifdef CONFIG_PM_SLEEP
 967 /* kill pending requests without uevent to avoid blocking suspend */
 968 static void kill_requests_without_uevent(void)
 969 {
 970         struct firmware_buf *buf;
 971         struct firmware_buf *next;
 972
 973         mutex_lock(&fw_lock);
 974         list_for_each_entry_safe(buf, next, &pending_fw_head, pending_list) {
 975                 if (!buf->need_uevent)
 976                          __fw_load_abort(buf);
 977         }
 978         mutex_unlock(&fw_lock);
 979 }
 980 #endif
 981
 982 #else /* CONFIG_FW_LOADER_USER_HELPER */
 983 static inline int
 984 fw_load_from_user_helper(struct firmware *firmware, const char *name,
 985                          struct device *device, unsigned int opt_flags,
 986                          long timeout)
 987 {
 988         return -ENOENT;
 989 }
 990
 991 /* No abort during direct loading */
 992 #define is_fw_load_aborted(buf) false
 993
 994 #ifdef CONFIG_PM_SLEEP
 995 static inline void kill_requests_without_uevent(void) { }
 996 #endif
 997
 998 #endif /* CONFIG_FW_LOADER_USER_HELPER */
 999
1000
1001 /* wait until the shared firmware_buf becomes ready (or error) */
1002 static int sync_cached_firmware_buf(struct firmware_buf *buf)
1003 {
1004         int ret = 0;
1005
1006         mutex_lock(&fw_lock);
1007         while (!test_bit(FW_STATUS_DONE, &buf->status)) {
1008                 if (is_fw_load_aborted(buf)) {
1009                         ret = -ENOENT;
1010                         break;
1011                 }
1012                 mutex_unlock(&fw_lock);
1013                 ret = wait_for_completion_interruptible(&buf->completion);
1014                 mutex_lock(&fw_lock);
1015         }
1016         mutex_unlock(&fw_lock);
1017         return ret;
1018 }
1019
1020 /* prepare firmware and firmware_buf structs;
1021  * return 0 if a firmware is already assigned, 1 if need to load one,
1022  * or a negative error code
1023  */
1024 static int
1025 _request_firmware_prepare(struct firmware **firmware_p, const char *name,
1026                           struct device *device)
1027 {
1028         struct firmware *firmware;
1029         struct firmware_buf *buf;
1030         int ret;
1031
1032         *firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
1033         if (!firmware) {
1034                 dev_err(device, "%s: kmalloc(struct firmware) failed\n",
1035                         __func__);
1036                 return -ENOMEM;
1037         }
1038
1039         if (fw_get_builtin_firmware(firmware, name)) {
1040                 dev_dbg(device, "firmware: using built-in firmware %s\n", name);
1041                 return 0; /* assigned */
1042         }
1043
1044         ret = fw_lookup_and_allocate_buf(name, &fw_cache, &buf);
1045
1046         /*
1047          * bind with 'buf' now to avoid warning in failure path
1048          * of requesting firmware.
1049          */
1050         firmware->priv = buf;
1051
1052         if (ret > 0) {
1053                 ret = sync_cached_firmware_buf(buf);
1054                 if (!ret) {
1055                         fw_set_page_data(buf, firmware);
1056                         return 0; /* assigned */
1057                 }
1058         }
1059
1060         if (ret < 0)
1061                 return ret;
1062         return 1; /* need to load */
1063 }
1064
1065 static int assign_firmware_buf(struct firmware *fw, struct device *device,
1066                                unsigned int opt_flags)
1067 {
1068         struct firmware_buf *buf = fw->priv;
1069
1070         mutex_lock(&fw_lock);
1071         if (!buf->size || is_fw_load_aborted(buf)) {
1072                 mutex_unlock(&fw_lock);
1073                 return -ENOENT;
1074         }
1075
1076         /*
1077          * add firmware name into devres list so that we can auto cache
1078          * and uncache firmware for device.
1079          *
1080          * device may has been deleted already, but the problem
1081          * should be fixed in devres or driver core.
1082          */
1083         /* don't cache firmware handled without uevent */
1084         if (device && (opt_flags & FW_OPT_UEVENT))
1085                 fw_add_devm_name(device, buf->fw_id);
1086
1087         /*
1088          * After caching firmware image is started, let it piggyback
1089          * on request firmware.
1090          */
1091         if (buf->fwc->state == FW_LOADER_START_CACHE) {
1092                 if (fw_cache_piggyback_on_request(buf->fw_id))
1093                         kref_get(&buf->ref);
1094         }
1095
1096         /* pass the pages buffer to driver at the last minute */
1097         fw_set_page_data(buf, fw);
1098         mutex_unlock(&fw_lock);
1099         return 0;
1100 }
1101
1102 /* called from request_firmware() and request_firmware_work_func() */
1103 static int
1104 _request_firmware(const struct firmware **firmware_p, const char *name,
1105                   struct device *device, unsigned int opt_flags)
1106 {
1107         struct firmware *fw;
1108         long timeout;
1109         int ret;
1110
1111         if (!firmware_p)
1112                 return -EINVAL;
1113
1114         if (!name || name[0] == '\0')
1115                 return -EINVAL;
1116
1117         ret = _request_firmware_prepare(&fw, name, device);
1118         if (ret <= 0) /* error or already assigned */
1119                 goto out;
1120
1121         ret = 0;
1122         timeout = firmware_loading_timeout();
1123         if (opt_flags & FW_OPT_NOWAIT) {
1124                 timeout = usermodehelper_read_lock_wait(timeout);
1125                 if (!timeout) {
1126                         dev_dbg(device, "firmware: %s loading timed out\n",
1127                                 name);
1128                         ret = -EBUSY;
1129                         goto out;
1130                 }
1131         } else {
1132                 ret = usermodehelper_read_trylock();
1133                 if (WARN_ON(ret)) {
1134                         dev_err(device, "firmware: %s will not be loaded\n",
1135                                 name);
1136                         goto out;
1137                 }
1138         }
1139
1140         ret = fw_get_filesystem_firmware(device, fw->priv);
1141         if (ret) {
1142                 if (!(opt_flags & FW_OPT_NO_WARN))
1143                         dev_warn(device,
1144                                  "Direct firmware load for %s failed with error %d\n",
1145                                  name, ret);
1146                 if (opt_flags & FW_OPT_USERHELPER) {
1147                         dev_warn(device, "Falling back to user helper\n");
1148                         ret = fw_load_from_user_helper(fw, name, device,
1149                                                        opt_flags, timeout);
1150                 }
1151         }
1152
1153         if (!ret)
1154                 ret = assign_firmware_buf(fw, device, opt_flags);
1155
1156         usermodehelper_read_unlock();
1157
1158  out:
1159         if (ret < 0) {
1160                 release_firmware(fw);
1161                 fw = NULL;
1162         }
1163
1164         *firmware_p = fw;
1165         return ret;
1166 }
1167
1168 /**
1169  * request_firmware: - send firmware request and wait for it
1170  * @firmware_p: pointer to firmware image
1171  * @name: name of firmware file
1172  * @device: device for which firmware is being loaded
1173  *
1174  *      @firmware_p will be used to return a firmware image by the name
1175  *      of @name for device @device.
1176  *
1177  *      Should be called from user context where sleeping is allowed.
1178  *
1179  *      @name will be used as $FIRMWARE in the uevent environment and
1180  *      should be distinctive enough not to be confused with any other
1181  *      firmware image for this or any other device.
1182  *
1183  *      Caller must hold the reference count of @device.
1184  *
1185  *      The function can be called safely inside device's suspend and
1186  *      resume callback.
1187  **/
1188 int
1189 request_firmware(const struct firmware **firmware_p, const char *name,
1190                  struct device *device)
1191 {
1192         int ret;
1193
1194         /* Need to pin this module until return */
1195         __module_get(THIS_MODULE);
1196         ret = _request_firmware(firmware_p, name, device,
1197                                 FW_OPT_UEVENT | FW_OPT_FALLBACK);
1198         module_put(THIS_MODULE);
1199         return ret;
1200 }
1201 EXPORT_SYMBOL(request_firmware);
1202
1203 /**
1204  * request_firmware_direct: - load firmware directly without usermode helper
1205  * @firmware_p: pointer to firmware image
1206  * @name: name of firmware file
1207  * @device: device for which firmware is being loaded
1208  *
1209  * This function works pretty much like request_firmware(), but this doesn't
1210  * fall back to usermode helper even if the firmware couldn't be loaded
1211  * directly from fs.  Hence it's useful for loading optional firmwares, which
1212  * aren't always present, without extra long timeouts of udev.
1213  **/
1214 int request_firmware_direct(const struct firmware **firmware_p,
1215                             const char *name, struct device *device)
1216 {
1217         int ret;
1218         __module_get(THIS_MODULE);
1219         ret = _request_firmware(firmware_p, name, device,
1220                                 FW_OPT_UEVENT | FW_OPT_NO_WARN);
1221         module_put(THIS_MODULE);
1222         return ret;
1223 }
1224 EXPORT_SYMBOL_GPL(request_firmware_direct);
1225
1226 /**
1227  * release_firmware: - release the resource associated with a firmware image
1228  * @fw: firmware resource to release
1229  **/
1230 void release_firmware(const struct firmware *fw)
1231 {
1232         if (fw) {
1233                 if (!fw_is_builtin_firmware(fw))
1234                         firmware_free_data(fw);
1235                 kfree(fw);
1236         }
1237 }
1238 EXPORT_SYMBOL(release_firmware);
1239
1240 /* Async support */
1241 struct firmware_work {
1242         struct work_struct work;
1243         struct module *module;
1244         const char *name;
1245         struct device *device;
1246         void *context;
1247         void (*cont)(const struct firmware *fw, void *context);
1248         unsigned int opt_flags;
1249 };
1250
1251 static void request_firmware_work_func(struct work_struct *work)
1252 {
1253         struct firmware_work *fw_work;
1254         const struct firmware *fw;
1255
1256         fw_work = container_of(work, struct firmware_work, work);
1257
1258         _request_firmware(&fw, fw_work->name, fw_work->device,
1259                           fw_work->opt_flags);
1260         fw_work->cont(fw, fw_work->context);
1261         put_device(fw_work->device); /* taken in request_firmware_nowait() */
1262
1263         module_put(fw_work->module);
1264         kfree(fw_work);
1265 }
1266
1267 /**
1268  * request_firmware_nowait - asynchronous version of request_firmware
1269  * @module: module requesting the firmware
1270  * @uevent: sends uevent to copy the firmware image if this flag
1271  *      is non-zero else the firmware copy must be done manually.
1272  * @name: name of firmware file
1273  * @device: device for which firmware is being loaded
1274  * @gfp: allocation flags
1275  * @context: will be passed over to @cont, and
1276  *      @fw may be %NULL if firmware request fails.
1277  * @cont: function will be called asynchronously when the firmware
1278  *      request is over.
1279  *
1280  *      Caller must hold the reference count of @device.
1281  *
1282  *      Asynchronous variant of request_firmware() for user contexts:
1283  *              - sleep for as small periods as possible since it may
1284  *              increase kernel boot time of built-in device drivers
1285  *              requesting firmware in their ->probe() methods, if
1286  *              @gfp is GFP_KERNEL.
1287  *
1288  *              - can't sleep at all if @gfp is GFP_ATOMIC.
1289  **/
1290 int
1291 request_firmware_nowait(
1292         struct module *module, bool uevent,
1293         const char *name, struct device *device, gfp_t gfp, void *context,
1294         void (*cont)(const struct firmware *fw, void *context))
1295 {
1296         struct firmware_work *fw_work;
1297
1298         fw_work = kzalloc(sizeof (struct firmware_work), gfp);
1299         if (!fw_work)
1300                 return -ENOMEM;
1301
1302         fw_work->module = module;
1303         fw_work->name = name;
1304         fw_work->device = device;
1305         fw_work->context = context;
1306         fw_work->cont = cont;
1307         fw_work->opt_flags = FW_OPT_NOWAIT | FW_OPT_FALLBACK |
1308                 (uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER);
1309
1310         if (!try_module_get(module)) {
1311                 kfree(fw_work);
1312                 return -EFAULT;
1313         }
1314
1315         get_device(fw_work->device);
1316         INIT_WORK(&fw_work->work, request_firmware_work_func);
1317         schedule_work(&fw_work->work);
1318         return 0;
1319 }
1320 EXPORT_SYMBOL(request_firmware_nowait);
1321
1322 #ifdef CONFIG_PM_SLEEP
1323 static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
1324
1325 /**
1326  * cache_firmware - cache one firmware image in kernel memory space
1327  * @fw_name: the firmware image name
1328  *
1329  * Cache firmware in kernel memory so that drivers can use it when
1330  * system isn't ready for them to request firmware image from userspace.
1331  * Once it returns successfully, driver can use request_firmware or its
1332  * nowait version to get the cached firmware without any interacting
1333  * with userspace
1334  *
1335  * Return 0 if the firmware image has been cached successfully
1336  * Return !0 otherwise
1337  *
1338  */
1339 static int cache_firmware(const char *fw_name)
1340 {
1341         int ret;
1342         const struct firmware *fw;
1343
1344         pr_debug("%s: %s\n", __func__, fw_name);
1345
1346         ret = request_firmware(&fw, fw_name, NULL);
1347         if (!ret)
1348                 kfree(fw);
1349
1350         pr_debug("%s: %s ret=%d\n", __func__, fw_name, ret);
1351
1352         return ret;
1353 }
1354
1355 static struct firmware_buf *fw_lookup_buf(const char *fw_name)
1356 {
1357         struct firmware_buf *tmp;
1358         struct firmware_cache *fwc = &fw_cache;
1359
1360         spin_lock(&fwc->lock);
1361         tmp = __fw_lookup_buf(fw_name);
1362         spin_unlock(&fwc->lock);
1363
1364         return tmp;
1365 }
1366
1367 /**
1368  * uncache_firmware - remove one cached firmware image
1369  * @fw_name: the firmware image name
1370  *
1371  * Uncache one firmware image which has been cached successfully
1372  * before.
1373  *
1374  * Return 0 if the firmware cache has been removed successfully
1375  * Return !0 otherwise
1376  *
1377  */
1378 static int uncache_firmware(const char *fw_name)
1379 {
1380         struct firmware_buf *buf;
1381         struct firmware fw;
1382
1383         pr_debug("%s: %s\n", __func__, fw_name);
1384
1385         if (fw_get_builtin_firmware(&fw, fw_name))
1386                 return 0;
1387
1388         buf = fw_lookup_buf(fw_name);
1389         if (buf) {
1390                 fw_free_buf(buf);
1391                 return 0;
1392         }
1393
1394         return -EINVAL;
1395 }
1396
1397 static struct fw_cache_entry *alloc_fw_cache_entry(const char *name)
1398 {
1399         struct fw_cache_entry *fce;
1400
1401         fce = kzalloc(sizeof(*fce) + strlen(name) + 1, GFP_ATOMIC);
1402         if (!fce)
1403                 goto exit;
1404
1405         strcpy(fce->name, name);
1406 exit:
1407         return fce;
1408 }
1409
1410 static int __fw_entry_found(const char *name)
1411 {
1412         struct firmware_cache *fwc = &fw_cache;
1413         struct fw_cache_entry *fce;
1414
1415         list_for_each_entry(fce, &fwc->fw_names, list) {
1416                 if (!strcmp(fce->name, name))
1417                         return 1;
1418         }
1419         return 0;
1420 }
1421
1422 static int fw_cache_piggyback_on_request(const char *name)
1423 {
1424         struct firmware_cache *fwc = &fw_cache;
1425         struct fw_cache_entry *fce;
1426         int ret = 0;
1427
1428         spin_lock(&fwc->name_lock);
1429         if (__fw_entry_found(name))
1430                 goto found;
1431
1432         fce = alloc_fw_cache_entry(name);
1433         if (fce) {
1434                 ret = 1;
1435                 list_add(&fce->list, &fwc->fw_names);
1436                 pr_debug("%s: fw: %s\n", __func__, name);
1437         }
1438 found:
1439         spin_unlock(&fwc->name_lock);
1440         return ret;
1441 }
1442
1443 static void free_fw_cache_entry(struct fw_cache_entry *fce)
1444 {
1445         kfree(fce);
1446 }
1447
1448 static void __async_dev_cache_fw_image(void *fw_entry,
1449                                        async_cookie_t cookie)
1450 {
1451         struct fw_cache_entry *fce = fw_entry;
1452         struct firmware_cache *fwc = &fw_cache;
1453         int ret;
1454
1455         ret = cache_firmware(fce->name);
1456         if (ret) {
1457                 spin_lock(&fwc->name_lock);
1458                 list_del(&fce->list);
1459                 spin_unlock(&fwc->name_lock);
1460
1461                 free_fw_cache_entry(fce);
1462         }
1463 }
1464
1465 /* called with dev->devres_lock held */
1466 static void dev_create_fw_entry(struct device *dev, void *res,
1467                                 void *data)
1468 {
1469         struct fw_name_devm *fwn = res;
1470         const char *fw_name = fwn->name;
1471         struct list_head *head = data;
1472         struct fw_cache_entry *fce;
1473
1474         fce = alloc_fw_cache_entry(fw_name);
1475         if (fce)
1476                 list_add(&fce->list, head);
1477 }
1478
1479 static int devm_name_match(struct device *dev, void *res,
1480                            void *match_data)
1481 {
1482         struct fw_name_devm *fwn = res;
1483         return (fwn->magic == (unsigned long)match_data);
1484 }
1485
1486 static void dev_cache_fw_image(struct device *dev, void *data)
1487 {
1488         LIST_HEAD(todo);
1489         struct fw_cache_entry *fce;
1490         struct fw_cache_entry *fce_next;
1491         struct firmware_cache *fwc = &fw_cache;
1492
1493         devres_for_each_res(dev, fw_name_devm_release,
1494                             devm_name_match, &fw_cache,
1495                             dev_create_fw_entry, &todo);
1496
1497         list_for_each_entry_safe(fce, fce_next, &todo, list) {
1498                 list_del(&fce->list);
1499
1500                 spin_lock(&fwc->name_lock);
1501                 /* only one cache entry for one firmware */
1502                 if (!__fw_entry_found(fce->name)) {
1503                         list_add(&fce->list, &fwc->fw_names);
1504                 } else {
1505                         free_fw_cache_entry(fce);
1506                         fce = NULL;
1507                 }
1508                 spin_unlock(&fwc->name_lock);
1509
1510                 if (fce)
1511                         async_schedule_domain(__async_dev_cache_fw_image,
1512                                               (void *)fce,
1513                                               &fw_cache_domain);
1514         }
1515 }
1516
1517 static void __device_uncache_fw_images(void)
1518 {
1519         struct firmware_cache *fwc = &fw_cache;
1520         struct fw_cache_entry *fce;
1521
1522         spin_lock(&fwc->name_lock);
1523         while (!list_empty(&fwc->fw_names)) {
1524                 fce = list_entry(fwc->fw_names.next,
1525                                 struct fw_cache_entry, list);
1526                 list_del(&fce->list);
1527                 spin_unlock(&fwc->name_lock);
1528
1529                 uncache_firmware(fce->name);
1530                 free_fw_cache_entry(fce);
1531
1532                 spin_lock(&fwc->name_lock);
1533         }
1534         spin_unlock(&fwc->name_lock);
1535 }
1536
1537 /**
1538  * device_cache_fw_images - cache devices' firmware
1539  *
1540  * If one device called request_firmware or its nowait version
1541  * successfully before, the firmware names are recored into the
1542  * device's devres link list, so device_cache_fw_images can call
1543  * cache_firmware() to cache these firmwares for the device,
1544  * then the device driver can load its firmwares easily at
1545  * time when system is not ready to complete loading firmware.
1546  */
1547 static void device_cache_fw_images(void)
1548 {
1549         struct firmware_cache *fwc = &fw_cache;
1550         int old_timeout;
1551         DEFINE_WAIT(wait);
1552
1553         pr_debug("%s\n", __func__);
1554
1555         /* cancel uncache work */
1556         cancel_delayed_work_sync(&fwc->work);
1557
1558         /*
1559          * use small loading timeout for caching devices' firmware
1560          * because all these firmware images have been loaded
1561          * successfully at lease once, also system is ready for
1562          * completing firmware loading now. The maximum size of
1563          * firmware in current distributions is about 2M bytes,
1564          * so 10 secs should be enough.
1565          */
1566         old_timeout = loading_timeout;
1567         loading_timeout = 10;
1568
1569         mutex_lock(&fw_lock);
1570         fwc->state = FW_LOADER_START_CACHE;
1571         dpm_for_each_dev(NULL, dev_cache_fw_image);
1572         mutex_unlock(&fw_lock);
1573
1574         /* wait for completion of caching firmware for all devices */
1575         async_synchronize_full_domain(&fw_cache_domain);
1576
1577         loading_timeout = old_timeout;
1578 }
1579
1580 /**
1581  * device_uncache_fw_images - uncache devices' firmware
1582  *
1583  * uncache all firmwares which have been cached successfully
1584  * by device_uncache_fw_images earlier
1585  */
1586 static void device_uncache_fw_images(void)
1587 {
1588         pr_debug("%s\n", __func__);
1589         __device_uncache_fw_images();
1590 }
1591
1592 static void device_uncache_fw_images_work(struct work_struct *work)
1593 {
1594         device_uncache_fw_images();
1595 }
1596
1597 /**
1598  * device_uncache_fw_images_delay - uncache devices firmwares
1599  * @delay: number of milliseconds to delay uncache device firmwares
1600  *
1601  * uncache all devices's firmwares which has been cached successfully
1602  * by device_cache_fw_images after @delay milliseconds.
1603  */
1604 static void device_uncache_fw_images_delay(unsigned long delay)
1605 {
1606         queue_delayed_work(system_power_efficient_wq, &fw_cache.work,
1607                            msecs_to_jiffies(delay));
1608 }
1609
1610 static int fw_pm_notify(struct notifier_block *notify_block,
1611                         unsigned long mode, void *unused)
1612 {
1613         switch (mode) {
1614         case PM_HIBERNATION_PREPARE:
1615         case PM_SUSPEND_PREPARE:
1616         case PM_RESTORE_PREPARE:
1617                 kill_requests_without_uevent();
1618                 device_cache_fw_images();
1619                 break;
1620
1621         case PM_POST_SUSPEND:
1622         case PM_POST_HIBERNATION:
1623         case PM_POST_RESTORE:
1624                 /*
1625                  * In case that system sleep failed and syscore_suspend is
1626                  * not called.
1627                  */
1628                 mutex_lock(&fw_lock);
1629                 fw_cache.state = FW_LOADER_NO_CACHE;
1630                 mutex_unlock(&fw_lock);
1631
1632                 device_uncache_fw_images_delay(10 * MSEC_PER_SEC);
1633                 break;
1634         }
1635
1636         return 0;
1637 }
1638
1639 /* stop caching firmware once syscore_suspend is reached */
1640 static int fw_suspend(void)
1641 {
1642         fw_cache.state = FW_LOADER_NO_CACHE;
1643         return 0;
1644 }
1645
1646 static struct syscore_ops fw_syscore_ops = {
1647         .suspend = fw_suspend,
1648 };
1649 #else
1650 static int fw_cache_piggyback_on_request(const char *name)
1651 {
1652         return 0;
1653 }
1654 #endif
1655
1656 static void __init fw_cache_init(void)
1657 {
1658         spin_lock_init(&fw_cache.lock);
1659         INIT_LIST_HEAD(&fw_cache.head);
1660         fw_cache.state = FW_LOADER_NO_CACHE;
1661
1662 #ifdef CONFIG_PM_SLEEP
1663         spin_lock_init(&fw_cache.name_lock);
1664         INIT_LIST_HEAD(&fw_cache.fw_names);
1665
1666         INIT_DELAYED_WORK(&fw_cache.work,
1667                           device_uncache_fw_images_work);
1668
1669         fw_cache.pm_notify.notifier_call = fw_pm_notify;
1670         register_pm_notifier(&fw_cache.pm_notify);
1671
1672         register_syscore_ops(&fw_syscore_ops);
1673 #endif
1674 }
1675
1676 static int __init firmware_class_init(void)
1677 {
1678         fw_cache_init();
1679 #ifdef CONFIG_FW_LOADER_USER_HELPER
1680         register_reboot_notifier(&fw_shutdown_nb);
1681         return class_register(&firmware_class);
1682 #else
1683         return 0;
1684 #endif
1685 }
1686
1687 static void __exit firmware_class_exit(void)
1688 {
1689 #ifdef CONFIG_PM_SLEEP
1690         unregister_syscore_ops(&fw_syscore_ops);
1691         unregister_pm_notifier(&fw_cache.pm_notify);
1692 #endif
1693 #ifdef CONFIG_FW_LOADER_USER_HELPER
1694         unregister_reboot_notifier(&fw_shutdown_nb);
1695         class_unregister(&firmware_class);
1696 #endif
1697 }
1698
1699 fs_initcall(firmware_class_init);
1700 module_exit(firmware_class_exit);