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         if (is_fw_load_aborted(buf))
 931                 retval = -EAGAIN;
 932         else if (!buf->data)
 933                 retval = -ENOMEM;
 934
 935         device_remove_file(f_dev, &dev_attr_loading);
 936 err_del_bin_attr:
 937         device_remove_bin_file(f_dev, &firmware_attr_data);
 938 err_del_dev:
 939         device_del(f_dev);
 940 err_put_dev:
 941         put_device(f_dev);
 942         return retval;
 943 }
 944
 945 static int fw_load_from_user_helper(struct firmware *firmware,
 946                                     const char *name, struct device *device,
 947                                     unsigned int opt_flags, long timeout)
 948 {
 949         struct firmware_priv *fw_priv;
 950
 951         fw_priv = fw_create_instance(firmware, name, device, opt_flags);
 952         if (IS_ERR(fw_priv))
 953                 return PTR_ERR(fw_priv);
 954
 955         fw_priv->buf = firmware->priv;
 956         return _request_firmware_load(fw_priv, opt_flags, timeout);
 957 }
 958
 959 #ifdef CONFIG_PM_SLEEP
 960 /* kill pending requests without uevent to avoid blocking suspend */
 961 static void kill_requests_without_uevent(void)
 962 {
 963         struct firmware_buf *buf;
 964         struct firmware_buf *next;
 965
 966         mutex_lock(&fw_lock);
 967         list_for_each_entry_safe(buf, next, &pending_fw_head, pending_list) {
 968                 if (!buf->need_uevent)
 969                          __fw_load_abort(buf);
 970         }
 971         mutex_unlock(&fw_lock);
 972 }
 973 #endif
 974
 975 #else /* CONFIG_FW_LOADER_USER_HELPER */
 976 static inline int
 977 fw_load_from_user_helper(struct firmware *firmware, const char *name,
 978                          struct device *device, unsigned int opt_flags,
 979                          long timeout)
 980 {
 981         return -ENOENT;
 982 }
 983
 984 /* No abort during direct loading */
 985 #define is_fw_load_aborted(buf) false
 986
 987 #ifdef CONFIG_PM_SLEEP
 988 static inline void kill_requests_without_uevent(void) { }
 989 #endif
 990
 991 #endif /* CONFIG_FW_LOADER_USER_HELPER */
 992
 993
 994 /* wait until the shared firmware_buf becomes ready (or error) */
 995 static int sync_cached_firmware_buf(struct firmware_buf *buf)
 996 {
 997         int ret = 0;
 998
 999         mutex_lock(&fw_lock);
1000         while (!test_bit(FW_STATUS_DONE, &buf->status)) {
1001                 if (is_fw_load_aborted(buf)) {
1002                         ret = -ENOENT;
1003                         break;
1004                 }
1005                 mutex_unlock(&fw_lock);
1006                 ret = wait_for_completion_interruptible(&buf->completion);
1007                 mutex_lock(&fw_lock);
1008         }
1009         mutex_unlock(&fw_lock);
1010         return ret;
1011 }
1012
1013 /* prepare firmware and firmware_buf structs;
1014  * return 0 if a firmware is already assigned, 1 if need to load one,
1015  * or a negative error code
1016  */
1017 static int
1018 _request_firmware_prepare(struct firmware **firmware_p, const char *name,
1019                           struct device *device)
1020 {
1021         struct firmware *firmware;
1022         struct firmware_buf *buf;
1023         int ret;
1024
1025         *firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
1026         if (!firmware) {
1027                 dev_err(device, "%s: kmalloc(struct firmware) failed\n",
1028                         __func__);
1029                 return -ENOMEM;
1030         }
1031
1032         if (fw_get_builtin_firmware(firmware, name)) {
1033                 dev_dbg(device, "firmware: using built-in firmware %s\n", name);
1034                 return 0; /* assigned */
1035         }
1036
1037         ret = fw_lookup_and_allocate_buf(name, &fw_cache, &buf);
1038
1039         /*
1040          * bind with 'buf' now to avoid warning in failure path
1041          * of requesting firmware.
1042          */
1043         firmware->priv = buf;
1044
1045         if (ret > 0) {
1046                 ret = sync_cached_firmware_buf(buf);
1047                 if (!ret) {
1048                         fw_set_page_data(buf, firmware);
1049                         return 0; /* assigned */
1050                 }
1051         }
1052
1053         if (ret < 0)
1054                 return ret;
1055         return 1; /* need to load */
1056 }
1057
1058 static int assign_firmware_buf(struct firmware *fw, struct device *device,
1059                                unsigned int opt_flags)
1060 {
1061         struct firmware_buf *buf = fw->priv;
1062
1063         mutex_lock(&fw_lock);
1064         if (!buf->size || is_fw_load_aborted(buf)) {
1065                 mutex_unlock(&fw_lock);
1066                 return -ENOENT;
1067         }
1068
1069         /*
1070          * add firmware name into devres list so that we can auto cache
1071          * and uncache firmware for device.
1072          *
1073          * device may has been deleted already, but the problem
1074          * should be fixed in devres or driver core.
1075          */
1076         /* don't cache firmware handled without uevent */
1077         if (device && (opt_flags & FW_OPT_UEVENT))
1078                 fw_add_devm_name(device, buf->fw_id);
1079
1080         /*
1081          * After caching firmware image is started, let it piggyback
1082          * on request firmware.
1083          */
1084         if (buf->fwc->state == FW_LOADER_START_CACHE) {
1085                 if (fw_cache_piggyback_on_request(buf->fw_id))
1086                         kref_get(&buf->ref);
1087         }
1088
1089         /* pass the pages buffer to driver at the last minute */
1090         fw_set_page_data(buf, fw);
1091         mutex_unlock(&fw_lock);
1092         return 0;
1093 }
1094
1095 /* called from request_firmware() and request_firmware_work_func() */
1096 static int
1097 _request_firmware(const struct firmware **firmware_p, const char *name,
1098                   struct device *device, unsigned int opt_flags)
1099 {
1100         struct firmware *fw;
1101         long timeout;
1102         int ret;
1103
1104         if (!firmware_p)
1105                 return -EINVAL;
1106
1107         if (!name || name[0] == '\0')
1108                 return -EINVAL;
1109
1110         ret = _request_firmware_prepare(&fw, name, device);
1111         if (ret <= 0) /* error or already assigned */
1112                 goto out;
1113
1114         ret = 0;
1115         timeout = firmware_loading_timeout();
1116         if (opt_flags & FW_OPT_NOWAIT) {
1117                 timeout = usermodehelper_read_lock_wait(timeout);
1118                 if (!timeout) {
1119                         dev_dbg(device, "firmware: %s loading timed out\n",
1120                                 name);
1121                         ret = -EBUSY;
1122                         goto out;
1123                 }
1124         } else {
1125                 ret = usermodehelper_read_trylock();
1126                 if (WARN_ON(ret)) {
1127                         dev_err(device, "firmware: %s will not be loaded\n",
1128                                 name);
1129                         goto out;
1130                 }
1131         }
1132
1133         ret = fw_get_filesystem_firmware(device, fw->priv);
1134         if (ret) {
1135                 if (!(opt_flags & FW_OPT_NO_WARN))
1136                         dev_warn(device,
1137                                  "Direct firmware load for %s failed with error %d\n",
1138                                  name, ret);
1139                 if (opt_flags & FW_OPT_USERHELPER) {
1140                         dev_warn(device, "Falling back to user helper\n");
1141                         ret = fw_load_from_user_helper(fw, name, device,
1142                                                        opt_flags, timeout);
1143                 }
1144         }
1145
1146         if (!ret)
1147                 ret = assign_firmware_buf(fw, device, opt_flags);
1148
1149         usermodehelper_read_unlock();
1150
1151  out:
1152         if (ret < 0) {
1153                 release_firmware(fw);
1154                 fw = NULL;
1155         }
1156
1157         *firmware_p = fw;
1158         return ret;
1159 }
1160
1161 /**
1162  * request_firmware: - send firmware request and wait for it
1163  * @firmware_p: pointer to firmware image
1164  * @name: name of firmware file
1165  * @device: device for which firmware is being loaded
1166  *
1167  *      @firmware_p will be used to return a firmware image by the name
1168  *      of @name for device @device.
1169  *
1170  *      Should be called from user context where sleeping is allowed.
1171  *
1172  *      @name will be used as $FIRMWARE in the uevent environment and
1173  *      should be distinctive enough not to be confused with any other
1174  *      firmware image for this or any other device.
1175  *
1176  *      Caller must hold the reference count of @device.
1177  *
1178  *      The function can be called safely inside device's suspend and
1179  *      resume callback.
1180  **/
1181 int
1182 request_firmware(const struct firmware **firmware_p, const char *name,
1183                  struct device *device)
1184 {
1185         int ret;
1186
1187         /* Need to pin this module until return */
1188         __module_get(THIS_MODULE);
1189         ret = _request_firmware(firmware_p, name, device,
1190                                 FW_OPT_UEVENT | FW_OPT_FALLBACK);
1191         module_put(THIS_MODULE);
1192         return ret;
1193 }
1194 EXPORT_SYMBOL(request_firmware);
1195
1196 /**
1197  * request_firmware: - load firmware directly without usermode helper
1198  * @firmware_p: pointer to firmware image
1199  * @name: name of firmware file
1200  * @device: device for which firmware is being loaded
1201  *
1202  * This function works pretty much like request_firmware(), but this doesn't
1203  * fall back to usermode helper even if the firmware couldn't be loaded
1204  * directly from fs.  Hence it's useful for loading optional firmwares, which
1205  * aren't always present, without extra long timeouts of udev.
1206  **/
1207 int request_firmware_direct(const struct firmware **firmware_p,
1208                             const char *name, struct device *device)
1209 {
1210         int ret;
1211         __module_get(THIS_MODULE);
1212         ret = _request_firmware(firmware_p, name, device,
1213                                 FW_OPT_UEVENT | FW_OPT_NO_WARN);
1214         module_put(THIS_MODULE);
1215         return ret;
1216 }
1217 EXPORT_SYMBOL_GPL(request_firmware_direct);
1218
1219 /**
1220  * release_firmware: - release the resource associated with a firmware image
1221  * @fw: firmware resource to release
1222  **/
1223 void release_firmware(const struct firmware *fw)
1224 {
1225         if (fw) {
1226                 if (!fw_is_builtin_firmware(fw))
1227                         firmware_free_data(fw);
1228                 kfree(fw);
1229         }
1230 }
1231 EXPORT_SYMBOL(release_firmware);
1232
1233 /* Async support */
1234 struct firmware_work {
1235         struct work_struct work;
1236         struct module *module;
1237         const char *name;
1238         struct device *device;
1239         void *context;
1240         void (*cont)(const struct firmware *fw, void *context);
1241         unsigned int opt_flags;
1242 };
1243
1244 static void request_firmware_work_func(struct work_struct *work)
1245 {
1246         struct firmware_work *fw_work;
1247         const struct firmware *fw;
1248
1249         fw_work = container_of(work, struct firmware_work, work);
1250
1251         _request_firmware(&fw, fw_work->name, fw_work->device,
1252                           fw_work->opt_flags);
1253         fw_work->cont(fw, fw_work->context);
1254         put_device(fw_work->device); /* taken in request_firmware_nowait() */
1255
1256         module_put(fw_work->module);
1257         kfree(fw_work);
1258 }
1259
1260 /**
1261  * request_firmware_nowait - asynchronous version of request_firmware
1262  * @module: module requesting the firmware
1263  * @uevent: sends uevent to copy the firmware image if this flag
1264  *      is non-zero else the firmware copy must be done manually.
1265  * @name: name of firmware file
1266  * @device: device for which firmware is being loaded
1267  * @gfp: allocation flags
1268  * @context: will be passed over to @cont, and
1269  *      @fw may be %NULL if firmware request fails.
1270  * @cont: function will be called asynchronously when the firmware
1271  *      request is over.
1272  *
1273  *      Caller must hold the reference count of @device.
1274  *
1275  *      Asynchronous variant of request_firmware() for user contexts:
1276  *              - sleep for as small periods as possible since it may
1277  *              increase kernel boot time of built-in device drivers
1278  *              requesting firmware in their ->probe() methods, if
1279  *              @gfp is GFP_KERNEL.
1280  *
1281  *              - can't sleep at all if @gfp is GFP_ATOMIC.
1282  **/
1283 int
1284 request_firmware_nowait(
1285         struct module *module, bool uevent,
1286         const char *name, struct device *device, gfp_t gfp, void *context,
1287         void (*cont)(const struct firmware *fw, void *context))
1288 {
1289         struct firmware_work *fw_work;
1290
1291         fw_work = kzalloc(sizeof (struct firmware_work), gfp);
1292         if (!fw_work)
1293                 return -ENOMEM;
1294
1295         fw_work->module = module;
1296         fw_work->name = name;
1297         fw_work->device = device;
1298         fw_work->context = context;
1299         fw_work->cont = cont;
1300         fw_work->opt_flags = FW_OPT_NOWAIT | FW_OPT_FALLBACK |
1301                 (uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER);
1302
1303         if (!try_module_get(module)) {
1304                 kfree(fw_work);
1305                 return -EFAULT;
1306         }
1307
1308         get_device(fw_work->device);
1309         INIT_WORK(&fw_work->work, request_firmware_work_func);
1310         schedule_work(&fw_work->work);
1311         return 0;
1312 }
1313 EXPORT_SYMBOL(request_firmware_nowait);
1314
1315 #ifdef CONFIG_PM_SLEEP
1316 static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
1317
1318 /**
1319  * cache_firmware - cache one firmware image in kernel memory space
1320  * @fw_name: the firmware image name
1321  *
1322  * Cache firmware in kernel memory so that drivers can use it when
1323  * system isn't ready for them to request firmware image from userspace.
1324  * Once it returns successfully, driver can use request_firmware or its
1325  * nowait version to get the cached firmware without any interacting
1326  * with userspace
1327  *
1328  * Return 0 if the firmware image has been cached successfully
1329  * Return !0 otherwise
1330  *
1331  */
1332 static int cache_firmware(const char *fw_name)
1333 {
1334         int ret;
1335         const struct firmware *fw;
1336
1337         pr_debug("%s: %s\n", __func__, fw_name);
1338
1339         ret = request_firmware(&fw, fw_name, NULL);
1340         if (!ret)
1341                 kfree(fw);
1342
1343         pr_debug("%s: %s ret=%d\n", __func__, fw_name, ret);
1344
1345         return ret;
1346 }
1347
1348 static struct firmware_buf *fw_lookup_buf(const char *fw_name)
1349 {
1350         struct firmware_buf *tmp;
1351         struct firmware_cache *fwc = &fw_cache;
1352
1353         spin_lock(&fwc->lock);
1354         tmp = __fw_lookup_buf(fw_name);
1355         spin_unlock(&fwc->lock);
1356
1357         return tmp;
1358 }
1359
1360 /**
1361  * uncache_firmware - remove one cached firmware image
1362  * @fw_name: the firmware image name
1363  *
1364  * Uncache one firmware image which has been cached successfully
1365  * before.
1366  *
1367  * Return 0 if the firmware cache has been removed successfully
1368  * Return !0 otherwise
1369  *
1370  */
1371 static int uncache_firmware(const char *fw_name)
1372 {
1373         struct firmware_buf *buf;
1374         struct firmware fw;
1375
1376         pr_debug("%s: %s\n", __func__, fw_name);
1377
1378         if (fw_get_builtin_firmware(&fw, fw_name))
1379                 return 0;
1380
1381         buf = fw_lookup_buf(fw_name);
1382         if (buf) {
1383                 fw_free_buf(buf);
1384                 return 0;
1385         }
1386
1387         return -EINVAL;
1388 }
1389
1390 static struct fw_cache_entry *alloc_fw_cache_entry(const char *name)
1391 {
1392         struct fw_cache_entry *fce;
1393
1394         fce = kzalloc(sizeof(*fce) + strlen(name) + 1, GFP_ATOMIC);
1395         if (!fce)
1396                 goto exit;
1397
1398         strcpy(fce->name, name);
1399 exit:
1400         return fce;
1401 }
1402
1403 static int __fw_entry_found(const char *name)
1404 {
1405         struct firmware_cache *fwc = &fw_cache;
1406         struct fw_cache_entry *fce;
1407
1408         list_for_each_entry(fce, &fwc->fw_names, list) {
1409                 if (!strcmp(fce->name, name))
1410                         return 1;
1411         }
1412         return 0;
1413 }
1414
1415 static int fw_cache_piggyback_on_request(const char *name)
1416 {
1417         struct firmware_cache *fwc = &fw_cache;
1418         struct fw_cache_entry *fce;
1419         int ret = 0;
1420
1421         spin_lock(&fwc->name_lock);
1422         if (__fw_entry_found(name))
1423                 goto found;
1424
1425         fce = alloc_fw_cache_entry(name);
1426         if (fce) {
1427                 ret = 1;
1428                 list_add(&fce->list, &fwc->fw_names);
1429                 pr_debug("%s: fw: %s\n", __func__, name);
1430         }
1431 found:
1432         spin_unlock(&fwc->name_lock);
1433         return ret;
1434 }
1435
1436 static void free_fw_cache_entry(struct fw_cache_entry *fce)
1437 {
1438         kfree(fce);
1439 }
1440
1441 static void __async_dev_cache_fw_image(void *fw_entry,
1442                                        async_cookie_t cookie)
1443 {
1444         struct fw_cache_entry *fce = fw_entry;
1445         struct firmware_cache *fwc = &fw_cache;
1446         int ret;
1447
1448         ret = cache_firmware(fce->name);
1449         if (ret) {
1450                 spin_lock(&fwc->name_lock);
1451                 list_del(&fce->list);
1452                 spin_unlock(&fwc->name_lock);
1453
1454                 free_fw_cache_entry(fce);
1455         }
1456 }
1457
1458 /* called with dev->devres_lock held */
1459 static void dev_create_fw_entry(struct device *dev, void *res,
1460                                 void *data)
1461 {
1462         struct fw_name_devm *fwn = res;
1463         const char *fw_name = fwn->name;
1464         struct list_head *head = data;
1465         struct fw_cache_entry *fce;
1466
1467         fce = alloc_fw_cache_entry(fw_name);
1468         if (fce)
1469                 list_add(&fce->list, head);
1470 }
1471
1472 static int devm_name_match(struct device *dev, void *res,
1473                            void *match_data)
1474 {
1475         struct fw_name_devm *fwn = res;
1476         return (fwn->magic == (unsigned long)match_data);
1477 }
1478
1479 static void dev_cache_fw_image(struct device *dev, void *data)
1480 {
1481         LIST_HEAD(todo);
1482         struct fw_cache_entry *fce;
1483         struct fw_cache_entry *fce_next;
1484         struct firmware_cache *fwc = &fw_cache;
1485
1486         devres_for_each_res(dev, fw_name_devm_release,
1487                             devm_name_match, &fw_cache,
1488                             dev_create_fw_entry, &todo);
1489
1490         list_for_each_entry_safe(fce, fce_next, &todo, list) {
1491                 list_del(&fce->list);
1492
1493                 spin_lock(&fwc->name_lock);
1494                 /* only one cache entry for one firmware */
1495                 if (!__fw_entry_found(fce->name)) {
1496                         list_add(&fce->list, &fwc->fw_names);
1497                 } else {
1498                         free_fw_cache_entry(fce);
1499                         fce = NULL;
1500                 }
1501                 spin_unlock(&fwc->name_lock);
1502
1503                 if (fce)
1504                         async_schedule_domain(__async_dev_cache_fw_image,
1505                                               (void *)fce,
1506                                               &fw_cache_domain);
1507         }
1508 }
1509
1510 static void __device_uncache_fw_images(void)
1511 {
1512         struct firmware_cache *fwc = &fw_cache;
1513         struct fw_cache_entry *fce;
1514
1515         spin_lock(&fwc->name_lock);
1516         while (!list_empty(&fwc->fw_names)) {
1517                 fce = list_entry(fwc->fw_names.next,
1518                                 struct fw_cache_entry, list);
1519                 list_del(&fce->list);
1520                 spin_unlock(&fwc->name_lock);
1521
1522                 uncache_firmware(fce->name);
1523                 free_fw_cache_entry(fce);
1524
1525                 spin_lock(&fwc->name_lock);
1526         }
1527         spin_unlock(&fwc->name_lock);
1528 }
1529
1530 /**
1531  * device_cache_fw_images - cache devices' firmware
1532  *
1533  * If one device called request_firmware or its nowait version
1534  * successfully before, the firmware names are recored into the
1535  * device's devres link list, so device_cache_fw_images can call
1536  * cache_firmware() to cache these firmwares for the device,
1537  * then the device driver can load its firmwares easily at
1538  * time when system is not ready to complete loading firmware.
1539  */
1540 static void device_cache_fw_images(void)
1541 {
1542         struct firmware_cache *fwc = &fw_cache;
1543         int old_timeout;
1544         DEFINE_WAIT(wait);
1545
1546         pr_debug("%s\n", __func__);
1547
1548         /* cancel uncache work */
1549         cancel_delayed_work_sync(&fwc->work);
1550
1551         /*
1552          * use small loading timeout for caching devices' firmware
1553          * because all these firmware images have been loaded
1554          * successfully at lease once, also system is ready for
1555          * completing firmware loading now. The maximum size of
1556          * firmware in current distributions is about 2M bytes,
1557          * so 10 secs should be enough.
1558          */
1559         old_timeout = loading_timeout;
1560         loading_timeout = 10;
1561
1562         mutex_lock(&fw_lock);
1563         fwc->state = FW_LOADER_START_CACHE;
1564         dpm_for_each_dev(NULL, dev_cache_fw_image);
1565         mutex_unlock(&fw_lock);
1566
1567         /* wait for completion of caching firmware for all devices */
1568         async_synchronize_full_domain(&fw_cache_domain);
1569
1570         loading_timeout = old_timeout;
1571 }
1572
1573 /**
1574  * device_uncache_fw_images - uncache devices' firmware
1575  *
1576  * uncache all firmwares which have been cached successfully
1577  * by device_uncache_fw_images earlier
1578  */
1579 static void device_uncache_fw_images(void)
1580 {
1581         pr_debug("%s\n", __func__);
1582         __device_uncache_fw_images();
1583 }
1584
1585 static void device_uncache_fw_images_work(struct work_struct *work)
1586 {
1587         device_uncache_fw_images();
1588 }
1589
1590 /**
1591  * device_uncache_fw_images_delay - uncache devices firmwares
1592  * @delay: number of milliseconds to delay uncache device firmwares
1593  *
1594  * uncache all devices's firmwares which has been cached successfully
1595  * by device_cache_fw_images after @delay milliseconds.
1596  */
1597 static void device_uncache_fw_images_delay(unsigned long delay)
1598 {
1599         queue_delayed_work(system_power_efficient_wq, &fw_cache.work,
1600                            msecs_to_jiffies(delay));
1601 }
1602
1603 static int fw_pm_notify(struct notifier_block *notify_block,
1604                         unsigned long mode, void *unused)
1605 {
1606         switch (mode) {
1607         case PM_HIBERNATION_PREPARE:
1608         case PM_SUSPEND_PREPARE:
1609         case PM_RESTORE_PREPARE:
1610                 kill_requests_without_uevent();
1611                 device_cache_fw_images();
1612                 break;
1613
1614         case PM_POST_SUSPEND:
1615         case PM_POST_HIBERNATION:
1616         case PM_POST_RESTORE:
1617                 /*
1618                  * In case that system sleep failed and syscore_suspend is
1619                  * not called.
1620                  */
1621                 mutex_lock(&fw_lock);
1622                 fw_cache.state = FW_LOADER_NO_CACHE;
1623                 mutex_unlock(&fw_lock);
1624
1625                 device_uncache_fw_images_delay(10 * MSEC_PER_SEC);
1626                 break;
1627         }
1628
1629         return 0;
1630 }
1631
1632 /* stop caching firmware once syscore_suspend is reached */
1633 static int fw_suspend(void)
1634 {
1635         fw_cache.state = FW_LOADER_NO_CACHE;
1636         return 0;
1637 }
1638
1639 static struct syscore_ops fw_syscore_ops = {
1640         .suspend = fw_suspend,
1641 };
1642 #else
1643 static int fw_cache_piggyback_on_request(const char *name)
1644 {
1645         return 0;
1646 }
1647 #endif
1648
1649 static void __init fw_cache_init(void)
1650 {
1651         spin_lock_init(&fw_cache.lock);
1652         INIT_LIST_HEAD(&fw_cache.head);
1653         fw_cache.state = FW_LOADER_NO_CACHE;
1654
1655 #ifdef CONFIG_PM_SLEEP
1656         spin_lock_init(&fw_cache.name_lock);
1657         INIT_LIST_HEAD(&fw_cache.fw_names);
1658
1659         INIT_DELAYED_WORK(&fw_cache.work,
1660                           device_uncache_fw_images_work);
1661
1662         fw_cache.pm_notify.notifier_call = fw_pm_notify;
1663         register_pm_notifier(&fw_cache.pm_notify);
1664
1665         register_syscore_ops(&fw_syscore_ops);
1666 #endif
1667 }
1668
1669 static int __init firmware_class_init(void)
1670 {
1671         fw_cache_init();
1672 #ifdef CONFIG_FW_LOADER_USER_HELPER
1673         register_reboot_notifier(&fw_shutdown_nb);
1674         return class_register(&firmware_class);
1675 #else
1676         return 0;
1677 #endif
1678 }
1679
1680 static void __exit firmware_class_exit(void)
1681 {
1682 #ifdef CONFIG_PM_SLEEP
1683         unregister_syscore_ops(&fw_syscore_ops);
1684         unregister_pm_notifier(&fw_cache.pm_notify);
1685 #endif
1686 #ifdef CONFIG_FW_LOADER_USER_HELPER
1687         unregister_reboot_notifier(&fw_shutdown_nb);
1688         class_unregister(&firmware_class);
1689 #endif
1690 }
1691
1692 fs_initcall(firmware_class_init);
1693 module_exit(firmware_class_exit);