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         if (buf->data)
 595                 vunmap(buf->data);
 596         buf->data = vmap(buf->pages, buf->nr_pages, 0, PAGE_KERNEL_RO);
 597         if (!buf->data)
 598                 return -ENOMEM;
 599         return 0;
 600 }
 601
 602 /**
 603  * firmware_loading_store - set value in the 'loading' control file
 604  * @dev: device pointer
 605  * @attr: device attribute pointer
 606  * @buf: buffer to scan for loading control value
 607  * @count: number of bytes in @buf
 608  *
 609  *      The relevant values are:
 610  *
 611  *       1: Start a load, discarding any previous partial load.
 612  *       0: Conclude the load and hand the data to the driver code.
 613  *      -1: Conclude the load with an error and discard any written data.
 614  **/
 615 static ssize_t firmware_loading_store(struct device *dev,
 616                                       struct device_attribute *attr,
 617                                       const char *buf, size_t count)
 618 {
 619         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 620         struct firmware_buf *fw_buf;
 621         ssize_t written = count;
 622         int loading = simple_strtol(buf, NULL, 10);
 623         int i;
 624
 625         mutex_lock(&fw_lock);
 626         fw_buf = fw_priv->buf;
 627         if (!fw_buf)
 628                 goto out;
 629
 630         switch (loading) {
 631         case 1:
 632                 /* discarding any previous partial load */
 633                 if (!test_bit(FW_STATUS_DONE, &fw_buf->status)) {
 634                         for (i = 0; i < fw_buf->nr_pages; i++)
 635                                 __free_page(fw_buf->pages[i]);
 636                         kfree(fw_buf->pages);
 637                         fw_buf->pages = NULL;
 638                         fw_buf->page_array_size = 0;
 639                         fw_buf->nr_pages = 0;
 640                         set_bit(FW_STATUS_LOADING, &fw_buf->status);
 641                 }
 642                 break;
 643         case 0:
 644                 if (test_bit(FW_STATUS_LOADING, &fw_buf->status)) {
 645                         int rc;
 646
 647                         set_bit(FW_STATUS_DONE, &fw_buf->status);
 648                         clear_bit(FW_STATUS_LOADING, &fw_buf->status);
 649
 650                         /*
 651                          * Several loading requests may be pending on
 652                          * one same firmware buf, so let all requests
 653                          * see the mapped 'buf->data' once the loading
 654                          * is completed.
 655                          * */
 656                         rc = fw_map_pages_buf(fw_buf);
 657                         if (rc)
 658                                 dev_err(dev, "%s: map pages failed\n",
 659                                         __func__);
 660                         else
 661                                 rc = security_kernel_fw_from_file(NULL,
 662                                                 fw_buf->data, fw_buf->size);
 663
 664                         /*
 665                          * Same logic as fw_load_abort, only the DONE bit
 666                          * is ignored and we set ABORT only on failure.
 667                          */
 668                         list_del_init(&fw_buf->pending_list);
 669                         if (rc) {
 670                                 set_bit(FW_STATUS_ABORT, &fw_buf->status);
 671                                 written = rc;
 672                         }
 673                         complete_all(&fw_buf->completion);
 674                         break;
 675                 }
 676                 /* fallthrough */
 677         default:
 678                 dev_err(dev, "%s: unexpected value (%d)\n", __func__, loading);
 679                 /* fallthrough */
 680         case -1:
 681                 fw_load_abort(fw_priv);
 682                 break;
 683         }
 684 out:
 685         mutex_unlock(&fw_lock);
 686         return written;
 687 }
 688
 689 static DEVICE_ATTR(loading, 0644, firmware_loading_show, firmware_loading_store);
 690
 691 static ssize_t firmware_data_read(struct file *filp, struct kobject *kobj,
 692                                   struct bin_attribute *bin_attr,
 693                                   char *buffer, loff_t offset, size_t count)
 694 {
 695         struct device *dev = kobj_to_dev(kobj);
 696         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 697         struct firmware_buf *buf;
 698         ssize_t ret_count;
 699
 700         mutex_lock(&fw_lock);
 701         buf = fw_priv->buf;
 702         if (!buf || test_bit(FW_STATUS_DONE, &buf->status)) {
 703                 ret_count = -ENODEV;
 704                 goto out;
 705         }
 706         if (offset > buf->size) {
 707                 ret_count = 0;
 708                 goto out;
 709         }
 710         if (count > buf->size - offset)
 711                 count = buf->size - offset;
 712
 713         ret_count = count;
 714
 715         while (count) {
 716                 void *page_data;
 717                 int page_nr = offset >> PAGE_SHIFT;
 718                 int page_ofs = offset & (PAGE_SIZE-1);
 719                 int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
 720
 721                 page_data = kmap(buf->pages[page_nr]);
 722
 723                 memcpy(buffer, page_data + page_ofs, page_cnt);
 724
 725                 kunmap(buf->pages[page_nr]);
 726                 buffer += page_cnt;
 727                 offset += page_cnt;
 728                 count -= page_cnt;
 729         }
 730 out:
 731         mutex_unlock(&fw_lock);
 732         return ret_count;
 733 }
 734
 735 static int fw_realloc_buffer(struct firmware_priv *fw_priv, int min_size)
 736 {
 737         struct firmware_buf *buf = fw_priv->buf;
 738         int pages_needed = PAGE_ALIGN(min_size) >> PAGE_SHIFT;
 739
 740         /* If the array of pages is too small, grow it... */
 741         if (buf->page_array_size < pages_needed) {
 742                 int new_array_size = max(pages_needed,
 743                                          buf->page_array_size * 2);
 744                 struct page **new_pages;
 745
 746                 new_pages = kmalloc(new_array_size * sizeof(void *),
 747                                     GFP_KERNEL);
 748                 if (!new_pages) {
 749                         fw_load_abort(fw_priv);
 750                         return -ENOMEM;
 751                 }
 752                 memcpy(new_pages, buf->pages,
 753                        buf->page_array_size * sizeof(void *));
 754                 memset(&new_pages[buf->page_array_size], 0, sizeof(void *) *
 755                        (new_array_size - buf->page_array_size));
 756                 kfree(buf->pages);
 757                 buf->pages = new_pages;
 758                 buf->page_array_size = new_array_size;
 759         }
 760
 761         while (buf->nr_pages < pages_needed) {
 762                 buf->pages[buf->nr_pages] =
 763                         alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
 764
 765                 if (!buf->pages[buf->nr_pages]) {
 766                         fw_load_abort(fw_priv);
 767                         return -ENOMEM;
 768                 }
 769                 buf->nr_pages++;
 770         }
 771         return 0;
 772 }
 773
 774 /**
 775  * firmware_data_write - write method for firmware
 776  * @filp: open sysfs file
 777  * @kobj: kobject for the device
 778  * @bin_attr: bin_attr structure
 779  * @buffer: buffer being written
 780  * @offset: buffer offset for write in total data store area
 781  * @count: buffer size
 782  *
 783  *      Data written to the 'data' attribute will be later handed to
 784  *      the driver as a firmware image.
 785  **/
 786 static ssize_t firmware_data_write(struct file *filp, struct kobject *kobj,
 787                                    struct bin_attribute *bin_attr,
 788                                    char *buffer, loff_t offset, size_t count)
 789 {
 790         struct device *dev = kobj_to_dev(kobj);
 791         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 792         struct firmware_buf *buf;
 793         ssize_t retval;
 794
 795         if (!capable(CAP_SYS_RAWIO))
 796                 return -EPERM;
 797
 798         mutex_lock(&fw_lock);
 799         buf = fw_priv->buf;
 800         if (!buf || test_bit(FW_STATUS_DONE, &buf->status)) {
 801                 retval = -ENODEV;
 802                 goto out;
 803         }
 804
 805         retval = fw_realloc_buffer(fw_priv, offset + count);
 806         if (retval)
 807                 goto out;
 808
 809         retval = count;
 810
 811         while (count) {
 812                 void *page_data;
 813                 int page_nr = offset >> PAGE_SHIFT;
 814                 int page_ofs = offset & (PAGE_SIZE - 1);
 815                 int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
 816
 817                 page_data = kmap(buf->pages[page_nr]);
 818
 819                 memcpy(page_data + page_ofs, buffer, page_cnt);
 820
 821                 kunmap(buf->pages[page_nr]);
 822                 buffer += page_cnt;
 823                 offset += page_cnt;
 824                 count -= page_cnt;
 825         }
 826
 827         buf->size = max_t(size_t, offset, buf->size);
 828 out:
 829         mutex_unlock(&fw_lock);
 830         return retval;
 831 }
 832
 833 static struct bin_attribute firmware_attr_data = {
 834         .attr = { .name = "data", .mode = 0644 },
 835         .size = 0,
 836         .read = firmware_data_read,
 837         .write = firmware_data_write,
 838 };
 839
 840 static void firmware_class_timeout_work(struct work_struct *work)
 841 {
 842         struct firmware_priv *fw_priv = container_of(work,
 843                         struct firmware_priv, timeout_work.work);
 844
 845         mutex_lock(&fw_lock);
 846         fw_load_abort(fw_priv);
 847         mutex_unlock(&fw_lock);
 848 }
 849
 850 static struct firmware_priv *
 851 fw_create_instance(struct firmware *firmware, const char *fw_name,
 852                    struct device *device, unsigned int opt_flags)
 853 {
 854         struct firmware_priv *fw_priv;
 855         struct device *f_dev;
 856
 857         fw_priv = kzalloc(sizeof(*fw_priv), GFP_KERNEL);
 858         if (!fw_priv) {
 859                 dev_err(device, "%s: kmalloc failed\n", __func__);
 860                 fw_priv = ERR_PTR(-ENOMEM);
 861                 goto exit;
 862         }
 863
 864         fw_priv->nowait = !!(opt_flags & FW_OPT_NOWAIT);
 865         fw_priv->fw = firmware;
 866         INIT_DELAYED_WORK(&fw_priv->timeout_work,
 867                 firmware_class_timeout_work);
 868
 869         f_dev = &fw_priv->dev;
 870
 871         device_initialize(f_dev);
 872         dev_set_name(f_dev, "%s", fw_name);
 873         f_dev->parent = device;
 874         f_dev->class = &firmware_class;
 875 exit:
 876         return fw_priv;
 877 }
 878
 879 /* load a firmware via user helper */
 880 static int _request_firmware_load(struct firmware_priv *fw_priv,
 881                                   unsigned int opt_flags, long timeout)
 882 {
 883         int retval = 0;
 884         struct device *f_dev = &fw_priv->dev;
 885         struct firmware_buf *buf = fw_priv->buf;
 886
 887         /* fall back on userspace loading */
 888         buf->is_paged_buf = true;
 889
 890         dev_set_uevent_suppress(f_dev, true);
 891
 892         retval = device_add(f_dev);
 893         if (retval) {
 894                 dev_err(f_dev, "%s: device_register failed\n", __func__);
 895                 goto err_put_dev;
 896         }
 897
 898         retval = device_create_bin_file(f_dev, &firmware_attr_data);
 899         if (retval) {
 900                 dev_err(f_dev, "%s: sysfs_create_bin_file failed\n", __func__);
 901                 goto err_del_dev;
 902         }
 903
 904         mutex_lock(&fw_lock);
 905         list_add(&buf->pending_list, &pending_fw_head);
 906         mutex_unlock(&fw_lock);
 907
 908         retval = device_create_file(f_dev, &dev_attr_loading);
 909         if (retval) {
 910                 mutex_lock(&fw_lock);
 911                 list_del_init(&buf->pending_list);
 912                 mutex_unlock(&fw_lock);
 913                 dev_err(f_dev, "%s: device_create_file failed\n", __func__);
 914                 goto err_del_bin_attr;
 915         }
 916
 917         if (opt_flags & FW_OPT_UEVENT) {
 918                 buf->need_uevent = true;
 919                 dev_set_uevent_suppress(f_dev, false);
 920                 dev_dbg(f_dev, "firmware: requesting %s\n", buf->fw_id);
 921                 if (timeout != MAX_SCHEDULE_TIMEOUT)
 922                         queue_delayed_work(system_power_efficient_wq,
 923                                            &fw_priv->timeout_work, timeout);
 924
 925                 kobject_uevent(&fw_priv->dev.kobj, KOBJ_ADD);
 926         }
 927
 928         wait_for_completion(&buf->completion);
 929
 930         cancel_delayed_work_sync(&fw_priv->timeout_work);
 931         if (is_fw_load_aborted(buf))
 932                 retval = -EAGAIN;
 933         else if (!buf->data)
 934                 retval = -ENOMEM;
 935
 936         device_remove_file(f_dev, &dev_attr_loading);
 937 err_del_bin_attr:
 938         device_remove_bin_file(f_dev, &firmware_attr_data);
 939 err_del_dev:
 940         device_del(f_dev);
 941 err_put_dev:
 942         put_device(f_dev);
 943         return retval;
 944 }
 945
 946 static int fw_load_from_user_helper(struct firmware *firmware,
 947                                     const char *name, struct device *device,
 948                                     unsigned int opt_flags, long timeout)
 949 {
 950         struct firmware_priv *fw_priv;
 951
 952         fw_priv = fw_create_instance(firmware, name, device, opt_flags);
 953         if (IS_ERR(fw_priv))
 954                 return PTR_ERR(fw_priv);
 955
 956         fw_priv->buf = firmware->priv;
 957         return _request_firmware_load(fw_priv, opt_flags, timeout);
 958 }
 959
 960 #ifdef CONFIG_PM_SLEEP
 961 /* kill pending requests without uevent to avoid blocking suspend */
 962 static void kill_requests_without_uevent(void)
 963 {
 964         struct firmware_buf *buf;
 965         struct firmware_buf *next;
 966
 967         mutex_lock(&fw_lock);
 968         list_for_each_entry_safe(buf, next, &pending_fw_head, pending_list) {
 969                 if (!buf->need_uevent)
 970                          __fw_load_abort(buf);
 971         }
 972         mutex_unlock(&fw_lock);
 973 }
 974 #endif
 975
 976 #else /* CONFIG_FW_LOADER_USER_HELPER */
 977 static inline int
 978 fw_load_from_user_helper(struct firmware *firmware, const char *name,
 979                          struct device *device, unsigned int opt_flags,
 980                          long timeout)
 981 {
 982         return -ENOENT;
 983 }
 984
 985 /* No abort during direct loading */
 986 #define is_fw_load_aborted(buf) false
 987
 988 #ifdef CONFIG_PM_SLEEP
 989 static inline void kill_requests_without_uevent(void) { }
 990 #endif
 991
 992 #endif /* CONFIG_FW_LOADER_USER_HELPER */
 993
 994
 995 /* wait until the shared firmware_buf becomes ready (or error) */
 996 static int sync_cached_firmware_buf(struct firmware_buf *buf)
 997 {
 998         int ret = 0;
 999
1000         mutex_lock(&fw_lock);
1001         while (!test_bit(FW_STATUS_DONE, &buf->status)) {
1002                 if (is_fw_load_aborted(buf)) {
1003                         ret = -ENOENT;
1004                         break;
1005                 }
1006                 mutex_unlock(&fw_lock);
1007                 wait_for_completion(&buf->completion);
1008                 mutex_lock(&fw_lock);
1009         }
1010         mutex_unlock(&fw_lock);
1011         return ret;
1012 }
1013
1014 /* prepare firmware and firmware_buf structs;
1015  * return 0 if a firmware is already assigned, 1 if need to load one,
1016  * or a negative error code
1017  */
1018 static int
1019 _request_firmware_prepare(struct firmware **firmware_p, const char *name,
1020                           struct device *device)
1021 {
1022         struct firmware *firmware;
1023         struct firmware_buf *buf;
1024         int ret;
1025
1026         *firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
1027         if (!firmware) {
1028                 dev_err(device, "%s: kmalloc(struct firmware) failed\n",
1029                         __func__);
1030                 return -ENOMEM;
1031         }
1032
1033         if (fw_get_builtin_firmware(firmware, name)) {
1034                 dev_dbg(device, "firmware: using built-in firmware %s\n", name);
1035                 return 0; /* assigned */
1036         }
1037
1038         ret = fw_lookup_and_allocate_buf(name, &fw_cache, &buf);
1039
1040         /*
1041          * bind with 'buf' now to avoid warning in failure path
1042          * of requesting firmware.
1043          */
1044         firmware->priv = buf;
1045
1046         if (ret > 0) {
1047                 ret = sync_cached_firmware_buf(buf);
1048                 if (!ret) {
1049                         fw_set_page_data(buf, firmware);
1050                         return 0; /* assigned */
1051                 }
1052         }
1053
1054         if (ret < 0)
1055                 return ret;
1056         return 1; /* need to load */
1057 }
1058
1059 static int assign_firmware_buf(struct firmware *fw, struct device *device,
1060                                unsigned int opt_flags)
1061 {
1062         struct firmware_buf *buf = fw->priv;
1063
1064         mutex_lock(&fw_lock);
1065         if (!buf->size || is_fw_load_aborted(buf)) {
1066                 mutex_unlock(&fw_lock);
1067                 return -ENOENT;
1068         }
1069
1070         /*
1071          * add firmware name into devres list so that we can auto cache
1072          * and uncache firmware for device.
1073          *
1074          * device may has been deleted already, but the problem
1075          * should be fixed in devres or driver core.
1076          */
1077         /* don't cache firmware handled without uevent */
1078         if (device && (opt_flags & FW_OPT_UEVENT))
1079                 fw_add_devm_name(device, buf->fw_id);
1080
1081         /*
1082          * After caching firmware image is started, let it piggyback
1083          * on request firmware.
1084          */
1085         if (buf->fwc->state == FW_LOADER_START_CACHE) {
1086                 if (fw_cache_piggyback_on_request(buf->fw_id))
1087                         kref_get(&buf->ref);
1088         }
1089
1090         /* pass the pages buffer to driver at the last minute */
1091         fw_set_page_data(buf, fw);
1092         mutex_unlock(&fw_lock);
1093         return 0;
1094 }
1095
1096 /* called from request_firmware() and request_firmware_work_func() */
1097 static int
1098 _request_firmware(const struct firmware **firmware_p, const char *name,
1099                   struct device *device, unsigned int opt_flags)
1100 {
1101         struct firmware *fw;
1102         long timeout;
1103         int ret;
1104
1105         if (!firmware_p)
1106                 return -EINVAL;
1107
1108         ret = _request_firmware_prepare(&fw, name, device);
1109         if (ret <= 0) /* error or already assigned */
1110                 goto out;
1111
1112         ret = 0;
1113         timeout = firmware_loading_timeout();
1114         if (opt_flags & FW_OPT_NOWAIT) {
1115                 timeout = usermodehelper_read_lock_wait(timeout);
1116                 if (!timeout) {
1117                         dev_dbg(device, "firmware: %s loading timed out\n",
1118                                 name);
1119                         ret = -EBUSY;
1120                         goto out;
1121                 }
1122         } else {
1123                 ret = usermodehelper_read_trylock();
1124                 if (WARN_ON(ret)) {
1125                         dev_err(device, "firmware: %s will not be loaded\n",
1126                                 name);
1127                         goto out;
1128                 }
1129         }
1130
1131         ret = fw_get_filesystem_firmware(device, fw->priv);
1132         if (ret) {
1133                 if (!(opt_flags & FW_OPT_NO_WARN))
1134                         dev_warn(device,
1135                                  "Direct firmware load for %s failed with error %d\n",
1136                                  name, ret);
1137                 if (opt_flags & FW_OPT_USERHELPER) {
1138                         dev_warn(device, "Falling back to user helper\n");
1139                         ret = fw_load_from_user_helper(fw, name, device,
1140                                                        opt_flags, timeout);
1141                 }
1142         }
1143
1144         if (!ret)
1145                 ret = assign_firmware_buf(fw, device, opt_flags);
1146
1147         usermodehelper_read_unlock();
1148
1149  out:
1150         if (ret < 0) {
1151                 release_firmware(fw);
1152                 fw = NULL;
1153         }
1154
1155         *firmware_p = fw;
1156         return ret;
1157 }
1158
1159 /**
1160  * request_firmware: - send firmware request and wait for it
1161  * @firmware_p: pointer to firmware image
1162  * @name: name of firmware file
1163  * @device: device for which firmware is being loaded
1164  *
1165  *      @firmware_p will be used to return a firmware image by the name
1166  *      of @name for device @device.
1167  *
1168  *      Should be called from user context where sleeping is allowed.
1169  *
1170  *      @name will be used as $FIRMWARE in the uevent environment and
1171  *      should be distinctive enough not to be confused with any other
1172  *      firmware image for this or any other device.
1173  *
1174  *      Caller must hold the reference count of @device.
1175  *
1176  *      The function can be called safely inside device's suspend and
1177  *      resume callback.
1178  **/
1179 int
1180 request_firmware(const struct firmware **firmware_p, const char *name,
1181                  struct device *device)
1182 {
1183         int ret;
1184
1185         /* Need to pin this module until return */
1186         __module_get(THIS_MODULE);
1187         ret = _request_firmware(firmware_p, name, device,
1188                                 FW_OPT_UEVENT | FW_OPT_FALLBACK);
1189         module_put(THIS_MODULE);
1190         return ret;
1191 }
1192 EXPORT_SYMBOL(request_firmware);
1193
1194 /**
1195  * request_firmware: - load firmware directly without usermode helper
1196  * @firmware_p: pointer to firmware image
1197  * @name: name of firmware file
1198  * @device: device for which firmware is being loaded
1199  *
1200  * This function works pretty much like request_firmware(), but this doesn't
1201  * fall back to usermode helper even if the firmware couldn't be loaded
1202  * directly from fs.  Hence it's useful for loading optional firmwares, which
1203  * aren't always present, without extra long timeouts of udev.
1204  **/
1205 int request_firmware_direct(const struct firmware **firmware_p,
1206                             const char *name, struct device *device)
1207 {
1208         int ret;
1209         __module_get(THIS_MODULE);
1210         ret = _request_firmware(firmware_p, name, device,
1211                                 FW_OPT_UEVENT | FW_OPT_NO_WARN);
1212         module_put(THIS_MODULE);
1213         return ret;
1214 }
1215 EXPORT_SYMBOL_GPL(request_firmware_direct);
1216
1217 /**
1218  * release_firmware: - release the resource associated with a firmware image
1219  * @fw: firmware resource to release
1220  **/
1221 void release_firmware(const struct firmware *fw)
1222 {
1223         if (fw) {
1224                 if (!fw_is_builtin_firmware(fw))
1225                         firmware_free_data(fw);
1226                 kfree(fw);
1227         }
1228 }
1229 EXPORT_SYMBOL(release_firmware);
1230
1231 /* Async support */
1232 struct firmware_work {
1233         struct work_struct work;
1234         struct module *module;
1235         const char *name;
1236         struct device *device;
1237         void *context;
1238         void (*cont)(const struct firmware *fw, void *context);
1239         unsigned int opt_flags;
1240 };
1241
1242 static void request_firmware_work_func(struct work_struct *work)
1243 {
1244         struct firmware_work *fw_work;
1245         const struct firmware *fw;
1246
1247         fw_work = container_of(work, struct firmware_work, work);
1248
1249         _request_firmware(&fw, fw_work->name, fw_work->device,
1250                           fw_work->opt_flags);
1251         fw_work->cont(fw, fw_work->context);
1252         put_device(fw_work->device); /* taken in request_firmware_nowait() */
1253
1254         module_put(fw_work->module);
1255         kfree(fw_work);
1256 }
1257
1258 /**
1259  * request_firmware_nowait - asynchronous version of request_firmware
1260  * @module: module requesting the firmware
1261  * @uevent: sends uevent to copy the firmware image if this flag
1262  *      is non-zero else the firmware copy must be done manually.
1263  * @name: name of firmware file
1264  * @device: device for which firmware is being loaded
1265  * @gfp: allocation flags
1266  * @context: will be passed over to @cont, and
1267  *      @fw may be %NULL if firmware request fails.
1268  * @cont: function will be called asynchronously when the firmware
1269  *      request is over.
1270  *
1271  *      Caller must hold the reference count of @device.
1272  *
1273  *      Asynchronous variant of request_firmware() for user contexts:
1274  *              - sleep for as small periods as possible since it may
1275  *              increase kernel boot time of built-in device drivers
1276  *              requesting firmware in their ->probe() methods, if
1277  *              @gfp is GFP_KERNEL.
1278  *
1279  *              - can't sleep at all if @gfp is GFP_ATOMIC.
1280  **/
1281 int
1282 request_firmware_nowait(
1283         struct module *module, bool uevent,
1284         const char *name, struct device *device, gfp_t gfp, void *context,
1285         void (*cont)(const struct firmware *fw, void *context))
1286 {
1287         struct firmware_work *fw_work;
1288
1289         fw_work = kzalloc(sizeof (struct firmware_work), gfp);
1290         if (!fw_work)
1291                 return -ENOMEM;
1292
1293         fw_work->module = module;
1294         fw_work->name = name;
1295         fw_work->device = device;
1296         fw_work->context = context;
1297         fw_work->cont = cont;
1298         fw_work->opt_flags = FW_OPT_NOWAIT | FW_OPT_FALLBACK |
1299                 (uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER);
1300
1301         if (!try_module_get(module)) {
1302                 kfree(fw_work);
1303                 return -EFAULT;
1304         }
1305
1306         get_device(fw_work->device);
1307         INIT_WORK(&fw_work->work, request_firmware_work_func);
1308         schedule_work(&fw_work->work);
1309         return 0;
1310 }
1311 EXPORT_SYMBOL(request_firmware_nowait);
1312
1313 #ifdef CONFIG_PM_SLEEP
1314 static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
1315
1316 /**
1317  * cache_firmware - cache one firmware image in kernel memory space
1318  * @fw_name: the firmware image name
1319  *
1320  * Cache firmware in kernel memory so that drivers can use it when
1321  * system isn't ready for them to request firmware image from userspace.
1322  * Once it returns successfully, driver can use request_firmware or its
1323  * nowait version to get the cached firmware without any interacting
1324  * with userspace
1325  *
1326  * Return 0 if the firmware image has been cached successfully
1327  * Return !0 otherwise
1328  *
1329  */
1330 static int cache_firmware(const char *fw_name)
1331 {
1332         int ret;
1333         const struct firmware *fw;
1334
1335         pr_debug("%s: %s\n", __func__, fw_name);
1336
1337         ret = request_firmware(&fw, fw_name, NULL);
1338         if (!ret)
1339                 kfree(fw);
1340
1341         pr_debug("%s: %s ret=%d\n", __func__, fw_name, ret);
1342
1343         return ret;
1344 }
1345
1346 static struct firmware_buf *fw_lookup_buf(const char *fw_name)
1347 {
1348         struct firmware_buf *tmp;
1349         struct firmware_cache *fwc = &fw_cache;
1350
1351         spin_lock(&fwc->lock);
1352         tmp = __fw_lookup_buf(fw_name);
1353         spin_unlock(&fwc->lock);
1354
1355         return tmp;
1356 }
1357
1358 /**
1359  * uncache_firmware - remove one cached firmware image
1360  * @fw_name: the firmware image name
1361  *
1362  * Uncache one firmware image which has been cached successfully
1363  * before.
1364  *
1365  * Return 0 if the firmware cache has been removed successfully
1366  * Return !0 otherwise
1367  *
1368  */
1369 static int uncache_firmware(const char *fw_name)
1370 {
1371         struct firmware_buf *buf;
1372         struct firmware fw;
1373
1374         pr_debug("%s: %s\n", __func__, fw_name);
1375
1376         if (fw_get_builtin_firmware(&fw, fw_name))
1377                 return 0;
1378
1379         buf = fw_lookup_buf(fw_name);
1380         if (buf) {
1381                 fw_free_buf(buf);
1382                 return 0;
1383         }
1384
1385         return -EINVAL;
1386 }
1387
1388 static struct fw_cache_entry *alloc_fw_cache_entry(const char *name)
1389 {
1390         struct fw_cache_entry *fce;
1391
1392         fce = kzalloc(sizeof(*fce) + strlen(name) + 1, GFP_ATOMIC);
1393         if (!fce)
1394                 goto exit;
1395
1396         strcpy(fce->name, name);
1397 exit:
1398         return fce;
1399 }
1400
1401 static int __fw_entry_found(const char *name)
1402 {
1403         struct firmware_cache *fwc = &fw_cache;
1404         struct fw_cache_entry *fce;
1405
1406         list_for_each_entry(fce, &fwc->fw_names, list) {
1407                 if (!strcmp(fce->name, name))
1408                         return 1;
1409         }
1410         return 0;
1411 }
1412
1413 static int fw_cache_piggyback_on_request(const char *name)
1414 {
1415         struct firmware_cache *fwc = &fw_cache;
1416         struct fw_cache_entry *fce;
1417         int ret = 0;
1418
1419         spin_lock(&fwc->name_lock);
1420         if (__fw_entry_found(name))
1421                 goto found;
1422
1423         fce = alloc_fw_cache_entry(name);
1424         if (fce) {
1425                 ret = 1;
1426                 list_add(&fce->list, &fwc->fw_names);
1427                 pr_debug("%s: fw: %s\n", __func__, name);
1428         }
1429 found:
1430         spin_unlock(&fwc->name_lock);
1431         return ret;
1432 }
1433
1434 static void free_fw_cache_entry(struct fw_cache_entry *fce)
1435 {
1436         kfree(fce);
1437 }
1438
1439 static void __async_dev_cache_fw_image(void *fw_entry,
1440                                        async_cookie_t cookie)
1441 {
1442         struct fw_cache_entry *fce = fw_entry;
1443         struct firmware_cache *fwc = &fw_cache;
1444         int ret;
1445
1446         ret = cache_firmware(fce->name);
1447         if (ret) {
1448                 spin_lock(&fwc->name_lock);
1449                 list_del(&fce->list);
1450                 spin_unlock(&fwc->name_lock);
1451
1452                 free_fw_cache_entry(fce);
1453         }
1454 }
1455
1456 /* called with dev->devres_lock held */
1457 static void dev_create_fw_entry(struct device *dev, void *res,
1458                                 void *data)
1459 {
1460         struct fw_name_devm *fwn = res;
1461         const char *fw_name = fwn->name;
1462         struct list_head *head = data;
1463         struct fw_cache_entry *fce;
1464
1465         fce = alloc_fw_cache_entry(fw_name);
1466         if (fce)
1467                 list_add(&fce->list, head);
1468 }
1469
1470 static int devm_name_match(struct device *dev, void *res,
1471                            void *match_data)
1472 {
1473         struct fw_name_devm *fwn = res;
1474         return (fwn->magic == (unsigned long)match_data);
1475 }
1476
1477 static void dev_cache_fw_image(struct device *dev, void *data)
1478 {
1479         LIST_HEAD(todo);
1480         struct fw_cache_entry *fce;
1481         struct fw_cache_entry *fce_next;
1482         struct firmware_cache *fwc = &fw_cache;
1483
1484         devres_for_each_res(dev, fw_name_devm_release,
1485                             devm_name_match, &fw_cache,
1486                             dev_create_fw_entry, &todo);
1487
1488         list_for_each_entry_safe(fce, fce_next, &todo, list) {
1489                 list_del(&fce->list);
1490
1491                 spin_lock(&fwc->name_lock);
1492                 /* only one cache entry for one firmware */
1493                 if (!__fw_entry_found(fce->name)) {
1494                         list_add(&fce->list, &fwc->fw_names);
1495                 } else {
1496                         free_fw_cache_entry(fce);
1497                         fce = NULL;
1498                 }
1499                 spin_unlock(&fwc->name_lock);
1500
1501                 if (fce)
1502                         async_schedule_domain(__async_dev_cache_fw_image,
1503                                               (void *)fce,
1504                                               &fw_cache_domain);
1505         }
1506 }
1507
1508 static void __device_uncache_fw_images(void)
1509 {
1510         struct firmware_cache *fwc = &fw_cache;
1511         struct fw_cache_entry *fce;
1512
1513         spin_lock(&fwc->name_lock);
1514         while (!list_empty(&fwc->fw_names)) {
1515                 fce = list_entry(fwc->fw_names.next,
1516                                 struct fw_cache_entry, list);
1517                 list_del(&fce->list);
1518                 spin_unlock(&fwc->name_lock);
1519
1520                 uncache_firmware(fce->name);
1521                 free_fw_cache_entry(fce);
1522
1523                 spin_lock(&fwc->name_lock);
1524         }
1525         spin_unlock(&fwc->name_lock);
1526 }
1527
1528 /**
1529  * device_cache_fw_images - cache devices' firmware
1530  *
1531  * If one device called request_firmware or its nowait version
1532  * successfully before, the firmware names are recored into the
1533  * device's devres link list, so device_cache_fw_images can call
1534  * cache_firmware() to cache these firmwares for the device,
1535  * then the device driver can load its firmwares easily at
1536  * time when system is not ready to complete loading firmware.
1537  */
1538 static void device_cache_fw_images(void)
1539 {
1540         struct firmware_cache *fwc = &fw_cache;
1541         int old_timeout;
1542         DEFINE_WAIT(wait);
1543
1544         pr_debug("%s\n", __func__);
1545
1546         /* cancel uncache work */
1547         cancel_delayed_work_sync(&fwc->work);
1548
1549         /*
1550          * use small loading timeout for caching devices' firmware
1551          * because all these firmware images have been loaded
1552          * successfully at lease once, also system is ready for
1553          * completing firmware loading now. The maximum size of
1554          * firmware in current distributions is about 2M bytes,
1555          * so 10 secs should be enough.
1556          */
1557         old_timeout = loading_timeout;
1558         loading_timeout = 10;
1559
1560         mutex_lock(&fw_lock);
1561         fwc->state = FW_LOADER_START_CACHE;
1562         dpm_for_each_dev(NULL, dev_cache_fw_image);
1563         mutex_unlock(&fw_lock);
1564
1565         /* wait for completion of caching firmware for all devices */
1566         async_synchronize_full_domain(&fw_cache_domain);
1567
1568         loading_timeout = old_timeout;
1569 }
1570
1571 /**
1572  * device_uncache_fw_images - uncache devices' firmware
1573  *
1574  * uncache all firmwares which have been cached successfully
1575  * by device_uncache_fw_images earlier
1576  */
1577 static void device_uncache_fw_images(void)
1578 {
1579         pr_debug("%s\n", __func__);
1580         __device_uncache_fw_images();
1581 }
1582
1583 static void device_uncache_fw_images_work(struct work_struct *work)
1584 {
1585         device_uncache_fw_images();
1586 }
1587
1588 /**
1589  * device_uncache_fw_images_delay - uncache devices firmwares
1590  * @delay: number of milliseconds to delay uncache device firmwares
1591  *
1592  * uncache all devices's firmwares which has been cached successfully
1593  * by device_cache_fw_images after @delay milliseconds.
1594  */
1595 static void device_uncache_fw_images_delay(unsigned long delay)
1596 {
1597         queue_delayed_work(system_power_efficient_wq, &fw_cache.work,
1598                            msecs_to_jiffies(delay));
1599 }
1600
1601 static int fw_pm_notify(struct notifier_block *notify_block,
1602                         unsigned long mode, void *unused)
1603 {
1604         switch (mode) {
1605         case PM_HIBERNATION_PREPARE:
1606         case PM_SUSPEND_PREPARE:
1607         case PM_RESTORE_PREPARE:
1608                 kill_requests_without_uevent();
1609                 device_cache_fw_images();
1610                 break;
1611
1612         case PM_POST_SUSPEND:
1613         case PM_POST_HIBERNATION:
1614         case PM_POST_RESTORE:
1615                 /*
1616                  * In case that system sleep failed and syscore_suspend is
1617                  * not called.
1618                  */
1619                 mutex_lock(&fw_lock);
1620                 fw_cache.state = FW_LOADER_NO_CACHE;
1621                 mutex_unlock(&fw_lock);
1622
1623                 device_uncache_fw_images_delay(10 * MSEC_PER_SEC);
1624                 break;
1625         }
1626
1627         return 0;
1628 }
1629
1630 /* stop caching firmware once syscore_suspend is reached */
1631 static int fw_suspend(void)
1632 {
1633         fw_cache.state = FW_LOADER_NO_CACHE;
1634         return 0;
1635 }
1636
1637 static struct syscore_ops fw_syscore_ops = {
1638         .suspend = fw_suspend,
1639 };
1640 #else
1641 static int fw_cache_piggyback_on_request(const char *name)
1642 {
1643         return 0;
1644 }
1645 #endif
1646
1647 static void __init fw_cache_init(void)
1648 {
1649         spin_lock_init(&fw_cache.lock);
1650         INIT_LIST_HEAD(&fw_cache.head);
1651         fw_cache.state = FW_LOADER_NO_CACHE;
1652
1653 #ifdef CONFIG_PM_SLEEP
1654         spin_lock_init(&fw_cache.name_lock);
1655         INIT_LIST_HEAD(&fw_cache.fw_names);
1656
1657         INIT_DELAYED_WORK(&fw_cache.work,
1658                           device_uncache_fw_images_work);
1659
1660         fw_cache.pm_notify.notifier_call = fw_pm_notify;
1661         register_pm_notifier(&fw_cache.pm_notify);
1662
1663         register_syscore_ops(&fw_syscore_ops);
1664 #endif
1665 }
1666
1667 static int __init firmware_class_init(void)
1668 {
1669         fw_cache_init();
1670 #ifdef CONFIG_FW_LOADER_USER_HELPER
1671         register_reboot_notifier(&fw_shutdown_nb);
1672         return class_register(&firmware_class);
1673 #else
1674         return 0;
1675 #endif
1676 }
1677
1678 static void __exit firmware_class_exit(void)
1679 {
1680 #ifdef CONFIG_PM_SLEEP
1681         unregister_syscore_ops(&fw_syscore_ops);
1682         unregister_pm_notifier(&fw_cache.pm_notify);
1683 #endif
1684 #ifdef CONFIG_FW_LOADER_USER_HELPER
1685         unregister_reboot_notifier(&fw_shutdown_nb);
1686         class_unregister(&firmware_class);
1687 #endif
1688 }
1689
1690 fs_initcall(firmware_class_init);
1691 module_exit(firmware_class_exit);