kernel/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_JIFFY_OFFSET;
  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         bool nowait;
 450         struct device dev;
 451         struct firmware_buf *buf;
 452         struct firmware *fw;
 453 };
 454
 455 static struct firmware_priv *to_firmware_priv(struct device *dev)
 456 {
 457         return container_of(dev, struct firmware_priv, dev);
 458 }
 459
 460 static void __fw_load_abort(struct firmware_buf *buf)
 461 {
 462         /*
 463          * There is a small window in which user can write to 'loading'
 464          * between loading done and disappearance of 'loading'
 465          */
 466         if (test_bit(FW_STATUS_DONE, &buf->status))
 467                 return;
 468
 469         list_del_init(&buf->pending_list);
 470         set_bit(FW_STATUS_ABORT, &buf->status);
 471         complete_all(&buf->completion);
 472 }
 473
 474 static void fw_load_abort(struct firmware_priv *fw_priv)
 475 {
 476         struct firmware_buf *buf = fw_priv->buf;
 477
 478         __fw_load_abort(buf);
 479
 480         /* avoid user action after loading abort */
 481         fw_priv->buf = NULL;
 482 }
 483
 484 #define is_fw_load_aborted(buf) \
 485         test_bit(FW_STATUS_ABORT, &(buf)->status)
 486
 487 static LIST_HEAD(pending_fw_head);
 488
 489 /* reboot notifier for avoid deadlock with usermode_lock */
 490 static int fw_shutdown_notify(struct notifier_block *unused1,
 491                               unsigned long unused2, void *unused3)
 492 {
 493         mutex_lock(&fw_lock);
 494         while (!list_empty(&pending_fw_head))
 495                 __fw_load_abort(list_first_entry(&pending_fw_head,
 496                                                struct firmware_buf,
 497                                                pending_list));
 498         mutex_unlock(&fw_lock);
 499         return NOTIFY_DONE;
 500 }
 501
 502 static struct notifier_block fw_shutdown_nb = {
 503         .notifier_call = fw_shutdown_notify,
 504 };
 505
 506 static ssize_t timeout_show(struct class *class, struct class_attribute *attr,
 507                             char *buf)
 508 {
 509         return sprintf(buf, "%d\n", loading_timeout);
 510 }
 511
 512 /**
 513  * firmware_timeout_store - set number of seconds to wait for firmware
 514  * @class: device class pointer
 515  * @attr: device attribute pointer
 516  * @buf: buffer to scan for timeout value
 517  * @count: number of bytes in @buf
 518  *
 519  *      Sets the number of seconds to wait for the firmware.  Once
 520  *      this expires an error will be returned to the driver and no
 521  *      firmware will be provided.
 522  *
 523  *      Note: zero means 'wait forever'.
 524  **/
 525 static ssize_t timeout_store(struct class *class, struct class_attribute *attr,
 526                              const char *buf, size_t count)
 527 {
 528         loading_timeout = simple_strtol(buf, NULL, 10);
 529         if (loading_timeout < 0)
 530                 loading_timeout = 0;
 531
 532         return count;
 533 }
 534
 535 static struct class_attribute firmware_class_attrs[] = {
 536         __ATTR_RW(timeout),
 537         __ATTR_NULL
 538 };
 539
 540 static void fw_dev_release(struct device *dev)
 541 {
 542         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 543
 544         kfree(fw_priv);
 545 }
 546
 547 static int do_firmware_uevent(struct firmware_priv *fw_priv, struct kobj_uevent_env *env)
 548 {
 549         if (add_uevent_var(env, "FIRMWARE=%s", fw_priv->buf->fw_id))
 550                 return -ENOMEM;
 551         if (add_uevent_var(env, "TIMEOUT=%i", loading_timeout))
 552                 return -ENOMEM;
 553         if (add_uevent_var(env, "ASYNC=%d", fw_priv->nowait))
 554                 return -ENOMEM;
 555
 556         return 0;
 557 }
 558
 559 static int firmware_uevent(struct device *dev, struct kobj_uevent_env *env)
 560 {
 561         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 562         int err = 0;
 563
 564         mutex_lock(&fw_lock);
 565         if (fw_priv->buf)
 566                 err = do_firmware_uevent(fw_priv, env);
 567         mutex_unlock(&fw_lock);
 568         return err;
 569 }
 570
 571 static struct class firmware_class = {
 572         .name           = "firmware",
 573         .class_attrs    = firmware_class_attrs,
 574         .dev_uevent     = firmware_uevent,
 575         .dev_release    = fw_dev_release,
 576 };
 577
 578 static ssize_t firmware_loading_show(struct device *dev,
 579                                      struct device_attribute *attr, char *buf)
 580 {
 581         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 582         int loading = 0;
 583
 584         mutex_lock(&fw_lock);
 585         if (fw_priv->buf)
 586                 loading = test_bit(FW_STATUS_LOADING, &fw_priv->buf->status);
 587         mutex_unlock(&fw_lock);
 588
 589         return sprintf(buf, "%d\n", loading);
 590 }
 591
 592 /* Some architectures don't have PAGE_KERNEL_RO */
 593 #ifndef PAGE_KERNEL_RO
 594 #define PAGE_KERNEL_RO PAGE_KERNEL
 595 #endif
 596
 597 /* one pages buffer should be mapped/unmapped only once */
 598 static int fw_map_pages_buf(struct firmware_buf *buf)
 599 {
 600         if (!buf->is_paged_buf)
 601                 return 0;
 602
 603         vunmap(buf->data);
 604         buf->data = vmap(buf->pages, buf->nr_pages, 0, PAGE_KERNEL_RO);
 605         if (!buf->data)
 606                 return -ENOMEM;
 607         return 0;
 608 }
 609
 610 /**
 611  * firmware_loading_store - set value in the 'loading' control file
 612  * @dev: device pointer
 613  * @attr: device attribute pointer
 614  * @buf: buffer to scan for loading control value
 615  * @count: number of bytes in @buf
 616  *
 617  *      The relevant values are:
 618  *
 619  *       1: Start a load, discarding any previous partial load.
 620  *       0: Conclude the load and hand the data to the driver code.
 621  *      -1: Conclude the load with an error and discard any written data.
 622  **/
 623 static ssize_t firmware_loading_store(struct device *dev,
 624                                       struct device_attribute *attr,
 625                                       const char *buf, size_t count)
 626 {
 627         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 628         struct firmware_buf *fw_buf;
 629         ssize_t written = count;
 630         int loading = simple_strtol(buf, NULL, 10);
 631         int i;
 632
 633         mutex_lock(&fw_lock);
 634         fw_buf = fw_priv->buf;
 635         if (!fw_buf)
 636                 goto out;
 637
 638         switch (loading) {
 639         case 1:
 640                 /* discarding any previous partial load */
 641                 if (!test_bit(FW_STATUS_DONE, &fw_buf->status)) {
 642                         for (i = 0; i < fw_buf->nr_pages; i++)
 643                                 __free_page(fw_buf->pages[i]);
 644                         kfree(fw_buf->pages);
 645                         fw_buf->pages = NULL;
 646                         fw_buf->page_array_size = 0;
 647                         fw_buf->nr_pages = 0;
 648                         set_bit(FW_STATUS_LOADING, &fw_buf->status);
 649                 }
 650                 break;
 651         case 0:
 652                 if (test_bit(FW_STATUS_LOADING, &fw_buf->status)) {
 653                         int rc;
 654
 655                         set_bit(FW_STATUS_DONE, &fw_buf->status);
 656                         clear_bit(FW_STATUS_LOADING, &fw_buf->status);
 657
 658                         /*
 659                          * Several loading requests may be pending on
 660                          * one same firmware buf, so let all requests
 661                          * see the mapped 'buf->data' once the loading
 662                          * is completed.
 663                          * */
 664                         rc = fw_map_pages_buf(fw_buf);
 665                         if (rc)
 666                                 dev_err(dev, "%s: map pages failed\n",
 667                                         __func__);
 668                         else
 669                                 rc = security_kernel_fw_from_file(NULL,
 670                                                 fw_buf->data, fw_buf->size);
 671
 672                         /*
 673                          * Same logic as fw_load_abort, only the DONE bit
 674                          * is ignored and we set ABORT only on failure.
 675                          */
 676                         list_del_init(&fw_buf->pending_list);
 677                         if (rc) {
 678                                 set_bit(FW_STATUS_ABORT, &fw_buf->status);
 679                                 written = rc;
 680                         }
 681                         complete_all(&fw_buf->completion);
 682                         break;
 683                 }
 684                 /* fallthrough */
 685         default:
 686                 dev_err(dev, "%s: unexpected value (%d)\n", __func__, loading);
 687                 /* fallthrough */
 688         case -1:
 689                 fw_load_abort(fw_priv);
 690                 break;
 691         }
 692 out:
 693         mutex_unlock(&fw_lock);
 694         return written;
 695 }
 696
 697 static DEVICE_ATTR(loading, 0644, firmware_loading_show, firmware_loading_store);
 698
 699 static ssize_t firmware_data_read(struct file *filp, struct kobject *kobj,
 700                                   struct bin_attribute *bin_attr,
 701                                   char *buffer, loff_t offset, size_t count)
 702 {
 703         struct device *dev = kobj_to_dev(kobj);
 704         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 705         struct firmware_buf *buf;
 706         ssize_t ret_count;
 707
 708         mutex_lock(&fw_lock);
 709         buf = fw_priv->buf;
 710         if (!buf || test_bit(FW_STATUS_DONE, &buf->status)) {
 711                 ret_count = -ENODEV;
 712                 goto out;
 713         }
 714         if (offset > buf->size) {
 715                 ret_count = 0;
 716                 goto out;
 717         }
 718         if (count > buf->size - offset)
 719                 count = buf->size - offset;
 720
 721         ret_count = count;
 722
 723         while (count) {
 724                 void *page_data;
 725                 int page_nr = offset >> PAGE_SHIFT;
 726                 int page_ofs = offset & (PAGE_SIZE-1);
 727                 int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
 728
 729                 page_data = kmap(buf->pages[page_nr]);
 730
 731                 memcpy(buffer, page_data + page_ofs, page_cnt);
 732
 733                 kunmap(buf->pages[page_nr]);
 734                 buffer += page_cnt;
 735                 offset += page_cnt;
 736                 count -= page_cnt;
 737         }
 738 out:
 739         mutex_unlock(&fw_lock);
 740         return ret_count;
 741 }
 742
 743 static int fw_realloc_buffer(struct firmware_priv *fw_priv, int min_size)
 744 {
 745         struct firmware_buf *buf = fw_priv->buf;
 746         int pages_needed = PAGE_ALIGN(min_size) >> PAGE_SHIFT;
 747
 748         /* If the array of pages is too small, grow it... */
 749         if (buf->page_array_size < pages_needed) {
 750                 int new_array_size = max(pages_needed,
 751                                          buf->page_array_size * 2);
 752                 struct page **new_pages;
 753
 754                 new_pages = kmalloc(new_array_size * sizeof(void *),
 755                                     GFP_KERNEL);
 756                 if (!new_pages) {
 757                         fw_load_abort(fw_priv);
 758                         return -ENOMEM;
 759                 }
 760                 memcpy(new_pages, buf->pages,
 761                        buf->page_array_size * sizeof(void *));
 762                 memset(&new_pages[buf->page_array_size], 0, sizeof(void *) *
 763                        (new_array_size - buf->page_array_size));
 764                 kfree(buf->pages);
 765                 buf->pages = new_pages;
 766                 buf->page_array_size = new_array_size;
 767         }
 768
 769         while (buf->nr_pages < pages_needed) {
 770                 buf->pages[buf->nr_pages] =
 771                         alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
 772
 773                 if (!buf->pages[buf->nr_pages]) {
 774                         fw_load_abort(fw_priv);
 775                         return -ENOMEM;
 776                 }
 777                 buf->nr_pages++;
 778         }
 779         return 0;
 780 }
 781
 782 /**
 783  * firmware_data_write - write method for firmware
 784  * @filp: open sysfs file
 785  * @kobj: kobject for the device
 786  * @bin_attr: bin_attr structure
 787  * @buffer: buffer being written
 788  * @offset: buffer offset for write in total data store area
 789  * @count: buffer size
 790  *
 791  *      Data written to the 'data' attribute will be later handed to
 792  *      the driver as a firmware image.
 793  **/
 794 static ssize_t firmware_data_write(struct file *filp, struct kobject *kobj,
 795                                    struct bin_attribute *bin_attr,
 796                                    char *buffer, loff_t offset, size_t count)
 797 {
 798         struct device *dev = kobj_to_dev(kobj);
 799         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 800         struct firmware_buf *buf;
 801         ssize_t retval;
 802
 803         if (!capable(CAP_SYS_RAWIO))
 804                 return -EPERM;
 805
 806         mutex_lock(&fw_lock);
 807         buf = fw_priv->buf;
 808         if (!buf || test_bit(FW_STATUS_DONE, &buf->status)) {
 809                 retval = -ENODEV;
 810                 goto out;
 811         }
 812
 813         retval = fw_realloc_buffer(fw_priv, offset + count);
 814         if (retval)
 815                 goto out;
 816
 817         retval = count;
 818
 819         while (count) {
 820                 void *page_data;
 821                 int page_nr = offset >> PAGE_SHIFT;
 822                 int page_ofs = offset & (PAGE_SIZE - 1);
 823                 int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
 824
 825                 page_data = kmap(buf->pages[page_nr]);
 826
 827                 memcpy(page_data + page_ofs, buffer, page_cnt);
 828
 829                 kunmap(buf->pages[page_nr]);
 830                 buffer += page_cnt;
 831                 offset += page_cnt;
 832                 count -= page_cnt;
 833         }
 834
 835         buf->size = max_t(size_t, offset, buf->size);
 836 out:
 837         mutex_unlock(&fw_lock);
 838         return retval;
 839 }
 840
 841 static struct bin_attribute firmware_attr_data = {
 842         .attr = { .name = "data", .mode = 0644 },
 843         .size = 0,
 844         .read = firmware_data_read,
 845         .write = firmware_data_write,
 846 };
 847
 848 static struct attribute *fw_dev_attrs[] = {
 849         &dev_attr_loading.attr,
 850         NULL
 851 };
 852
 853 static struct bin_attribute *fw_dev_bin_attrs[] = {
 854         &firmware_attr_data,
 855         NULL
 856 };
 857
 858 static const struct attribute_group fw_dev_attr_group = {
 859         .attrs = fw_dev_attrs,
 860         .bin_attrs = fw_dev_bin_attrs,
 861 };
 862
 863 static const struct attribute_group *fw_dev_attr_groups[] = {
 864         &fw_dev_attr_group,
 865         NULL
 866 };
 867
 868 static struct firmware_priv *
 869 fw_create_instance(struct firmware *firmware, const char *fw_name,
 870                    struct device *device, unsigned int opt_flags)
 871 {
 872         struct firmware_priv *fw_priv;
 873         struct device *f_dev;
 874
 875         fw_priv = kzalloc(sizeof(*fw_priv), GFP_KERNEL);
 876         if (!fw_priv) {
 877                 fw_priv = ERR_PTR(-ENOMEM);
 878                 goto exit;
 879         }
 880
 881         fw_priv->nowait = !!(opt_flags & FW_OPT_NOWAIT);
 882         fw_priv->fw = firmware;
 883         f_dev = &fw_priv->dev;
 884
 885         device_initialize(f_dev);
 886         dev_set_name(f_dev, "%s", fw_name);
 887         f_dev->parent = device;
 888         f_dev->class = &firmware_class;
 889         f_dev->groups = fw_dev_attr_groups;
 890 exit:
 891         return fw_priv;
 892 }
 893
 894 /* load a firmware via user helper */
 895 static int _request_firmware_load(struct firmware_priv *fw_priv,
 896                                   unsigned int opt_flags, long timeout)
 897 {
 898         int retval = 0;
 899         struct device *f_dev = &fw_priv->dev;
 900         struct firmware_buf *buf = fw_priv->buf;
 901
 902         /* fall back on userspace loading */
 903         buf->is_paged_buf = true;
 904
 905         dev_set_uevent_suppress(f_dev, true);
 906
 907         retval = device_add(f_dev);
 908         if (retval) {
 909                 dev_err(f_dev, "%s: device_register failed\n", __func__);
 910                 goto err_put_dev;
 911         }
 912
 913         mutex_lock(&fw_lock);
 914         list_add(&buf->pending_list, &pending_fw_head);
 915         mutex_unlock(&fw_lock);
 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                 kobject_uevent(&fw_priv->dev.kobj, KOBJ_ADD);
 922         } else {
 923                 timeout = MAX_JIFFY_OFFSET;
 924         }
 925
 926         retval = wait_for_completion_interruptible_timeout(&buf->completion,
 927                         timeout);
 928         if (retval == -ERESTARTSYS || !retval) {
 929                 mutex_lock(&fw_lock);
 930                 fw_load_abort(fw_priv);
 931                 mutex_unlock(&fw_lock);
 932         } else if (retval > 0) {
 933                 retval = 0;
 934         }
 935
 936         if (is_fw_load_aborted(buf))
 937                 retval = -EAGAIN;
 938         else if (!buf->data)
 939                 retval = -ENOMEM;
 940
 941         device_del(f_dev);
 942 err_put_dev:
 943         put_device(f_dev);
 944         return retval;
 945 }
 946
 947 static int fw_load_from_user_helper(struct firmware *firmware,
 948                                     const char *name, struct device *device,
 949                                     unsigned int opt_flags, long timeout)
 950 {
 951         struct firmware_priv *fw_priv;
 952
 953         fw_priv = fw_create_instance(firmware, name, device, opt_flags);
 954         if (IS_ERR(fw_priv))
 955                 return PTR_ERR(fw_priv);
 956
 957         fw_priv->buf = firmware->priv;
 958         return _request_firmware_load(fw_priv, opt_flags, timeout);
 959 }
 960
 961 #ifdef CONFIG_PM_SLEEP
 962 /* kill pending requests without uevent to avoid blocking suspend */
 963 static void kill_requests_without_uevent(void)
 964 {
 965         struct firmware_buf *buf;
 966         struct firmware_buf *next;
 967
 968         mutex_lock(&fw_lock);
 969         list_for_each_entry_safe(buf, next, &pending_fw_head, pending_list) {
 970                 if (!buf->need_uevent)
 971                          __fw_load_abort(buf);
 972         }
 973         mutex_unlock(&fw_lock);
 974 }
 975 #endif
 976
 977 #else /* CONFIG_FW_LOADER_USER_HELPER */
 978 static inline int
 979 fw_load_from_user_helper(struct firmware *firmware, const char *name,
 980                          struct device *device, unsigned int opt_flags,
 981                          long timeout)
 982 {
 983         return -ENOENT;
 984 }
 985
 986 /* No abort during direct loading */
 987 #define is_fw_load_aborted(buf) false
 988
 989 #ifdef CONFIG_PM_SLEEP
 990 static inline void kill_requests_without_uevent(void) { }
 991 #endif
 992
 993 #endif /* CONFIG_FW_LOADER_USER_HELPER */
 994
 995
 996 /* wait until the shared firmware_buf becomes ready (or error) */
 997 static int sync_cached_firmware_buf(struct firmware_buf *buf)
 998 {
 999         int ret = 0;
1000
1001         mutex_lock(&fw_lock);
1002         while (!test_bit(FW_STATUS_DONE, &buf->status)) {
1003                 if (is_fw_load_aborted(buf)) {
1004                         ret = -ENOENT;
1005                         break;
1006                 }
1007                 mutex_unlock(&fw_lock);
1008                 ret = wait_for_completion_interruptible(&buf->completion);
1009                 mutex_lock(&fw_lock);
1010         }
1011         mutex_unlock(&fw_lock);
1012         return ret;
1013 }
1014
1015 /* prepare firmware and firmware_buf structs;
1016  * return 0 if a firmware is already assigned, 1 if need to load one,
1017  * or a negative error code
1018  */
1019 static int
1020 _request_firmware_prepare(struct firmware **firmware_p, const char *name,
1021                           struct device *device)
1022 {
1023         struct firmware *firmware;
1024         struct firmware_buf *buf;
1025         int ret;
1026
1027         *firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
1028         if (!firmware) {
1029                 dev_err(device, "%s: kmalloc(struct firmware) failed\n",
1030                         __func__);
1031                 return -ENOMEM;
1032         }
1033
1034         if (fw_get_builtin_firmware(firmware, name)) {
1035                 dev_dbg(device, "firmware: using built-in firmware %s\n", name);
1036                 return 0; /* assigned */
1037         }
1038
1039         ret = fw_lookup_and_allocate_buf(name, &fw_cache, &buf);
1040
1041         /*
1042          * bind with 'buf' now to avoid warning in failure path
1043          * of requesting firmware.
1044          */
1045         firmware->priv = buf;
1046
1047         if (ret > 0) {
1048                 ret = sync_cached_firmware_buf(buf);
1049                 if (!ret) {
1050                         fw_set_page_data(buf, firmware);
1051                         return 0; /* assigned */
1052                 }
1053         }
1054
1055         if (ret < 0)
1056                 return ret;
1057         return 1; /* need to load */
1058 }
1059
1060 static int assign_firmware_buf(struct firmware *fw, struct device *device,
1061                                unsigned int opt_flags)
1062 {
1063         struct firmware_buf *buf = fw->priv;
1064
1065         mutex_lock(&fw_lock);
1066         if (!buf->size || is_fw_load_aborted(buf)) {
1067                 mutex_unlock(&fw_lock);
1068                 return -ENOENT;
1069         }
1070
1071         /*
1072          * add firmware name into devres list so that we can auto cache
1073          * and uncache firmware for device.
1074          *
1075          * device may has been deleted already, but the problem
1076          * should be fixed in devres or driver core.
1077          */
1078         /* don't cache firmware handled without uevent */
1079         if (device && (opt_flags & FW_OPT_UEVENT))
1080                 fw_add_devm_name(device, buf->fw_id);
1081
1082         /*
1083          * After caching firmware image is started, let it piggyback
1084          * on request firmware.
1085          */
1086         if (buf->fwc->state == FW_LOADER_START_CACHE) {
1087                 if (fw_cache_piggyback_on_request(buf->fw_id))
1088                         kref_get(&buf->ref);
1089         }
1090
1091         /* pass the pages buffer to driver at the last minute */
1092         fw_set_page_data(buf, fw);
1093         mutex_unlock(&fw_lock);
1094         return 0;
1095 }
1096
1097 /* called from request_firmware() and request_firmware_work_func() */
1098 static int
1099 _request_firmware(const struct firmware **firmware_p, const char *name,
1100                   struct device *device, unsigned int opt_flags)
1101 {
1102         struct firmware *fw;
1103         long timeout;
1104         int ret;
1105
1106         if (!firmware_p)
1107                 return -EINVAL;
1108
1109         if (!name || name[0] == '\0')
1110                 return -EINVAL;
1111
1112         ret = _request_firmware_prepare(&fw, name, device);
1113         if (ret <= 0) /* error or already assigned */
1114                 goto out;
1115
1116         ret = 0;
1117         timeout = firmware_loading_timeout();
1118         if (opt_flags & FW_OPT_NOWAIT) {
1119                 timeout = usermodehelper_read_lock_wait(timeout);
1120                 if (!timeout) {
1121                         dev_dbg(device, "firmware: %s loading timed out\n",
1122                                 name);
1123                         ret = -EBUSY;
1124                         goto out;
1125                 }
1126         } else {
1127                 ret = usermodehelper_read_trylock();
1128                 if (WARN_ON(ret)) {
1129                         dev_err(device, "firmware: %s will not be loaded\n",
1130                                 name);
1131                         goto out;
1132                 }
1133         }
1134
1135         ret = fw_get_filesystem_firmware(device, fw->priv);
1136         if (ret) {
1137                 if (!(opt_flags & FW_OPT_NO_WARN))
1138                         dev_warn(device,
1139                                  "Direct firmware load for %s failed with error %d\n",
1140                                  name, ret);
1141                 if (opt_flags & FW_OPT_USERHELPER) {
1142                         dev_warn(device, "Falling back to user helper\n");
1143                         ret = fw_load_from_user_helper(fw, name, device,
1144                                                        opt_flags, timeout);
1145                 }
1146         }
1147
1148         if (!ret)
1149                 ret = assign_firmware_buf(fw, device, opt_flags);
1150
1151         usermodehelper_read_unlock();
1152
1153  out:
1154         if (ret < 0) {
1155                 release_firmware(fw);
1156                 fw = NULL;
1157         }
1158
1159         *firmware_p = fw;
1160         return ret;
1161 }
1162
1163 /**
1164  * request_firmware: - send firmware request and wait for it
1165  * @firmware_p: pointer to firmware image
1166  * @name: name of firmware file
1167  * @device: device for which firmware is being loaded
1168  *
1169  *      @firmware_p will be used to return a firmware image by the name
1170  *      of @name for device @device.
1171  *
1172  *      Should be called from user context where sleeping is allowed.
1173  *
1174  *      @name will be used as $FIRMWARE in the uevent environment and
1175  *      should be distinctive enough not to be confused with any other
1176  *      firmware image for this or any other device.
1177  *
1178  *      Caller must hold the reference count of @device.
1179  *
1180  *      The function can be called safely inside device's suspend and
1181  *      resume callback.
1182  **/
1183 int
1184 request_firmware(const struct firmware **firmware_p, const char *name,
1185                  struct device *device)
1186 {
1187         int ret;
1188
1189         /* Need to pin this module until return */
1190         __module_get(THIS_MODULE);
1191         ret = _request_firmware(firmware_p, name, device,
1192                                 FW_OPT_UEVENT | FW_OPT_FALLBACK);
1193         module_put(THIS_MODULE);
1194         return ret;
1195 }
1196 EXPORT_SYMBOL(request_firmware);
1197
1198 /**
1199  * request_firmware_direct: - load firmware directly without usermode helper
1200  * @firmware_p: pointer to firmware image
1201  * @name: name of firmware file
1202  * @device: device for which firmware is being loaded
1203  *
1204  * This function works pretty much like request_firmware(), but this doesn't
1205  * fall back to usermode helper even if the firmware couldn't be loaded
1206  * directly from fs.  Hence it's useful for loading optional firmwares, which
1207  * aren't always present, without extra long timeouts of udev.
1208  **/
1209 int request_firmware_direct(const struct firmware **firmware_p,
1210                             const char *name, struct device *device)
1211 {
1212         int ret;
1213
1214         __module_get(THIS_MODULE);
1215         ret = _request_firmware(firmware_p, name, device,
1216                                 FW_OPT_UEVENT | FW_OPT_NO_WARN);
1217         module_put(THIS_MODULE);
1218         return ret;
1219 }
1220 EXPORT_SYMBOL_GPL(request_firmware_direct);
1221
1222 /**
1223  * release_firmware: - release the resource associated with a firmware image
1224  * @fw: firmware resource to release
1225  **/
1226 void release_firmware(const struct firmware *fw)
1227 {
1228         if (fw) {
1229                 if (!fw_is_builtin_firmware(fw))
1230                         firmware_free_data(fw);
1231                 kfree(fw);
1232         }
1233 }
1234 EXPORT_SYMBOL(release_firmware);
1235
1236 /* Async support */
1237 struct firmware_work {
1238         struct work_struct work;
1239         struct module *module;
1240         const char *name;
1241         struct device *device;
1242         void *context;
1243         void (*cont)(const struct firmware *fw, void *context);
1244         unsigned int opt_flags;
1245 };
1246
1247 static void request_firmware_work_func(struct work_struct *work)
1248 {
1249         struct firmware_work *fw_work;
1250         const struct firmware *fw;
1251
1252         fw_work = container_of(work, struct firmware_work, work);
1253
1254         _request_firmware(&fw, fw_work->name, fw_work->device,
1255                           fw_work->opt_flags);
1256         fw_work->cont(fw, fw_work->context);
1257         put_device(fw_work->device); /* taken in request_firmware_nowait() */
1258
1259         module_put(fw_work->module);
1260         kfree(fw_work);
1261 }
1262
1263 /**
1264  * request_firmware_nowait - asynchronous version of request_firmware
1265  * @module: module requesting the firmware
1266  * @uevent: sends uevent to copy the firmware image if this flag
1267  *      is non-zero else the firmware copy must be done manually.
1268  * @name: name of firmware file
1269  * @device: device for which firmware is being loaded
1270  * @gfp: allocation flags
1271  * @context: will be passed over to @cont, and
1272  *      @fw may be %NULL if firmware request fails.
1273  * @cont: function will be called asynchronously when the firmware
1274  *      request is over.
1275  *
1276  *      Caller must hold the reference count of @device.
1277  *
1278  *      Asynchronous variant of request_firmware() for user contexts:
1279  *              - sleep for as small periods as possible since it may
1280  *              increase kernel boot time of built-in device drivers
1281  *              requesting firmware in their ->probe() methods, if
1282  *              @gfp is GFP_KERNEL.
1283  *
1284  *              - can't sleep at all if @gfp is GFP_ATOMIC.
1285  **/
1286 int
1287 request_firmware_nowait(
1288         struct module *module, bool uevent,
1289         const char *name, struct device *device, gfp_t gfp, void *context,
1290         void (*cont)(const struct firmware *fw, void *context))
1291 {
1292         struct firmware_work *fw_work;
1293
1294         fw_work = kzalloc(sizeof(struct firmware_work), gfp);
1295         if (!fw_work)
1296                 return -ENOMEM;
1297
1298         fw_work->module = module;
1299         fw_work->name = name;
1300         fw_work->device = device;
1301         fw_work->context = context;
1302         fw_work->cont = cont;
1303         fw_work->opt_flags = FW_OPT_NOWAIT | FW_OPT_FALLBACK |
1304                 (uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER);
1305
1306         if (!try_module_get(module)) {
1307                 kfree(fw_work);
1308                 return -EFAULT;
1309         }
1310
1311         get_device(fw_work->device);
1312         INIT_WORK(&fw_work->work, request_firmware_work_func);
1313         schedule_work(&fw_work->work);
1314         return 0;
1315 }
1316 EXPORT_SYMBOL(request_firmware_nowait);
1317
1318 #ifdef CONFIG_PM_SLEEP
1319 static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
1320
1321 /**
1322  * cache_firmware - cache one firmware image in kernel memory space
1323  * @fw_name: the firmware image name
1324  *
1325  * Cache firmware in kernel memory so that drivers can use it when
1326  * system isn't ready for them to request firmware image from userspace.
1327  * Once it returns successfully, driver can use request_firmware or its
1328  * nowait version to get the cached firmware without any interacting
1329  * with userspace
1330  *
1331  * Return 0 if the firmware image has been cached successfully
1332  * Return !0 otherwise
1333  *
1334  */
1335 static int cache_firmware(const char *fw_name)
1336 {
1337         int ret;
1338         const struct firmware *fw;
1339
1340         pr_debug("%s: %s\n", __func__, fw_name);
1341
1342         ret = request_firmware(&fw, fw_name, NULL);
1343         if (!ret)
1344                 kfree(fw);
1345
1346         pr_debug("%s: %s ret=%d\n", __func__, fw_name, ret);
1347
1348         return ret;
1349 }
1350
1351 static struct firmware_buf *fw_lookup_buf(const char *fw_name)
1352 {
1353         struct firmware_buf *tmp;
1354         struct firmware_cache *fwc = &fw_cache;
1355
1356         spin_lock(&fwc->lock);
1357         tmp = __fw_lookup_buf(fw_name);
1358         spin_unlock(&fwc->lock);
1359
1360         return tmp;
1361 }
1362
1363 /**
1364  * uncache_firmware - remove one cached firmware image
1365  * @fw_name: the firmware image name
1366  *
1367  * Uncache one firmware image which has been cached successfully
1368  * before.
1369  *
1370  * Return 0 if the firmware cache has been removed successfully
1371  * Return !0 otherwise
1372  *
1373  */
1374 static int uncache_firmware(const char *fw_name)
1375 {
1376         struct firmware_buf *buf;
1377         struct firmware fw;
1378
1379         pr_debug("%s: %s\n", __func__, fw_name);
1380
1381         if (fw_get_builtin_firmware(&fw, fw_name))
1382                 return 0;
1383
1384         buf = fw_lookup_buf(fw_name);
1385         if (buf) {
1386                 fw_free_buf(buf);
1387                 return 0;
1388         }
1389
1390         return -EINVAL;
1391 }
1392
1393 static struct fw_cache_entry *alloc_fw_cache_entry(const char *name)
1394 {
1395         struct fw_cache_entry *fce;
1396
1397         fce = kzalloc(sizeof(*fce) + strlen(name) + 1, GFP_ATOMIC);
1398         if (!fce)
1399                 goto exit;
1400
1401         strcpy(fce->name, name);
1402 exit:
1403         return fce;
1404 }
1405
1406 static int __fw_entry_found(const char *name)
1407 {
1408         struct firmware_cache *fwc = &fw_cache;
1409         struct fw_cache_entry *fce;
1410
1411         list_for_each_entry(fce, &fwc->fw_names, list) {
1412                 if (!strcmp(fce->name, name))
1413                         return 1;
1414         }
1415         return 0;
1416 }
1417
1418 static int fw_cache_piggyback_on_request(const char *name)
1419 {
1420         struct firmware_cache *fwc = &fw_cache;
1421         struct fw_cache_entry *fce;
1422         int ret = 0;
1423
1424         spin_lock(&fwc->name_lock);
1425         if (__fw_entry_found(name))
1426                 goto found;
1427
1428         fce = alloc_fw_cache_entry(name);
1429         if (fce) {
1430                 ret = 1;
1431                 list_add(&fce->list, &fwc->fw_names);
1432                 pr_debug("%s: fw: %s\n", __func__, name);
1433         }
1434 found:
1435         spin_unlock(&fwc->name_lock);
1436         return ret;
1437 }
1438
1439 static void free_fw_cache_entry(struct fw_cache_entry *fce)
1440 {
1441         kfree(fce);
1442 }
1443
1444 static void __async_dev_cache_fw_image(void *fw_entry,
1445                                        async_cookie_t cookie)
1446 {
1447         struct fw_cache_entry *fce = fw_entry;
1448         struct firmware_cache *fwc = &fw_cache;
1449         int ret;
1450
1451         ret = cache_firmware(fce->name);
1452         if (ret) {
1453                 spin_lock(&fwc->name_lock);
1454                 list_del(&fce->list);
1455                 spin_unlock(&fwc->name_lock);
1456
1457                 free_fw_cache_entry(fce);
1458         }
1459 }
1460
1461 /* called with dev->devres_lock held */
1462 static void dev_create_fw_entry(struct device *dev, void *res,
1463                                 void *data)
1464 {
1465         struct fw_name_devm *fwn = res;
1466         const char *fw_name = fwn->name;
1467         struct list_head *head = data;
1468         struct fw_cache_entry *fce;
1469
1470         fce = alloc_fw_cache_entry(fw_name);
1471         if (fce)
1472                 list_add(&fce->list, head);
1473 }
1474
1475 static int devm_name_match(struct device *dev, void *res,
1476                            void *match_data)
1477 {
1478         struct fw_name_devm *fwn = res;
1479         return (fwn->magic == (unsigned long)match_data);
1480 }
1481
1482 static void dev_cache_fw_image(struct device *dev, void *data)
1483 {
1484         LIST_HEAD(todo);
1485         struct fw_cache_entry *fce;
1486         struct fw_cache_entry *fce_next;
1487         struct firmware_cache *fwc = &fw_cache;
1488
1489         devres_for_each_res(dev, fw_name_devm_release,
1490                             devm_name_match, &fw_cache,
1491                             dev_create_fw_entry, &todo);
1492
1493         list_for_each_entry_safe(fce, fce_next, &todo, list) {
1494                 list_del(&fce->list);
1495
1496                 spin_lock(&fwc->name_lock);
1497                 /* only one cache entry for one firmware */
1498                 if (!__fw_entry_found(fce->name)) {
1499                         list_add(&fce->list, &fwc->fw_names);
1500                 } else {
1501                         free_fw_cache_entry(fce);
1502                         fce = NULL;
1503                 }
1504                 spin_unlock(&fwc->name_lock);
1505
1506                 if (fce)
1507                         async_schedule_domain(__async_dev_cache_fw_image,
1508                                               (void *)fce,
1509                                               &fw_cache_domain);
1510         }
1511 }
1512
1513 static void __device_uncache_fw_images(void)
1514 {
1515         struct firmware_cache *fwc = &fw_cache;
1516         struct fw_cache_entry *fce;
1517
1518         spin_lock(&fwc->name_lock);
1519         while (!list_empty(&fwc->fw_names)) {
1520                 fce = list_entry(fwc->fw_names.next,
1521                                 struct fw_cache_entry, list);
1522                 list_del(&fce->list);
1523                 spin_unlock(&fwc->name_lock);
1524
1525                 uncache_firmware(fce->name);
1526                 free_fw_cache_entry(fce);
1527
1528                 spin_lock(&fwc->name_lock);
1529         }
1530         spin_unlock(&fwc->name_lock);
1531 }
1532
1533 /**
1534  * device_cache_fw_images - cache devices' firmware
1535  *
1536  * If one device called request_firmware or its nowait version
1537  * successfully before, the firmware names are recored into the
1538  * device's devres link list, so device_cache_fw_images can call
1539  * cache_firmware() to cache these firmwares for the device,
1540  * then the device driver can load its firmwares easily at
1541  * time when system is not ready to complete loading firmware.
1542  */
1543 static void device_cache_fw_images(void)
1544 {
1545         struct firmware_cache *fwc = &fw_cache;
1546         int old_timeout;
1547         DEFINE_WAIT(wait);
1548
1549         pr_debug("%s\n", __func__);
1550
1551         /* cancel uncache work */
1552         cancel_delayed_work_sync(&fwc->work);
1553
1554         /*
1555          * use small loading timeout for caching devices' firmware
1556          * because all these firmware images have been loaded
1557          * successfully at lease once, also system is ready for
1558          * completing firmware loading now. The maximum size of
1559          * firmware in current distributions is about 2M bytes,
1560          * so 10 secs should be enough.
1561          */
1562         old_timeout = loading_timeout;
1563         loading_timeout = 10;
1564
1565         mutex_lock(&fw_lock);
1566         fwc->state = FW_LOADER_START_CACHE;
1567         dpm_for_each_dev(NULL, dev_cache_fw_image);
1568         mutex_unlock(&fw_lock);
1569
1570         /* wait for completion of caching firmware for all devices */
1571         async_synchronize_full_domain(&fw_cache_domain);
1572
1573         loading_timeout = old_timeout;
1574 }
1575
1576 /**
1577  * device_uncache_fw_images - uncache devices' firmware
1578  *
1579  * uncache all firmwares which have been cached successfully
1580  * by device_uncache_fw_images earlier
1581  */
1582 static void device_uncache_fw_images(void)
1583 {
1584         pr_debug("%s\n", __func__);
1585         __device_uncache_fw_images();
1586 }
1587
1588 static void device_uncache_fw_images_work(struct work_struct *work)
1589 {
1590         device_uncache_fw_images();
1591 }
1592
1593 /**
1594  * device_uncache_fw_images_delay - uncache devices firmwares
1595  * @delay: number of milliseconds to delay uncache device firmwares
1596  *
1597  * uncache all devices's firmwares which has been cached successfully
1598  * by device_cache_fw_images after @delay milliseconds.
1599  */
1600 static void device_uncache_fw_images_delay(unsigned long delay)
1601 {
1602         queue_delayed_work(system_power_efficient_wq, &fw_cache.work,
1603                            msecs_to_jiffies(delay));
1604 }
1605
1606 static int fw_pm_notify(struct notifier_block *notify_block,
1607                         unsigned long mode, void *unused)
1608 {
1609         switch (mode) {
1610         case PM_HIBERNATION_PREPARE:
1611         case PM_SUSPEND_PREPARE:
1612         case PM_RESTORE_PREPARE:
1613                 kill_requests_without_uevent();
1614                 device_cache_fw_images();
1615                 break;
1616
1617         case PM_POST_SUSPEND:
1618         case PM_POST_HIBERNATION:
1619         case PM_POST_RESTORE:
1620                 /*
1621                  * In case that system sleep failed and syscore_suspend is
1622                  * not called.
1623                  */
1624                 mutex_lock(&fw_lock);
1625                 fw_cache.state = FW_LOADER_NO_CACHE;
1626                 mutex_unlock(&fw_lock);
1627
1628                 device_uncache_fw_images_delay(10 * MSEC_PER_SEC);
1629                 break;
1630         }
1631
1632         return 0;
1633 }
1634
1635 /* stop caching firmware once syscore_suspend is reached */
1636 static int fw_suspend(void)
1637 {
1638         fw_cache.state = FW_LOADER_NO_CACHE;
1639         return 0;
1640 }
1641
1642 static struct syscore_ops fw_syscore_ops = {
1643         .suspend = fw_suspend,
1644 };
1645 #else
1646 static int fw_cache_piggyback_on_request(const char *name)
1647 {
1648         return 0;
1649 }
1650 #endif
1651
1652 static void __init fw_cache_init(void)
1653 {
1654         spin_lock_init(&fw_cache.lock);
1655         INIT_LIST_HEAD(&fw_cache.head);
1656         fw_cache.state = FW_LOADER_NO_CACHE;
1657
1658 #ifdef CONFIG_PM_SLEEP
1659         spin_lock_init(&fw_cache.name_lock);
1660         INIT_LIST_HEAD(&fw_cache.fw_names);
1661
1662         INIT_DELAYED_WORK(&fw_cache.work,
1663                           device_uncache_fw_images_work);
1664
1665         fw_cache.pm_notify.notifier_call = fw_pm_notify;
1666         register_pm_notifier(&fw_cache.pm_notify);
1667
1668         register_syscore_ops(&fw_syscore_ops);
1669 #endif
1670 }
1671
1672 static int __init firmware_class_init(void)
1673 {
1674         fw_cache_init();
1675 #ifdef CONFIG_FW_LOADER_USER_HELPER
1676         register_reboot_notifier(&fw_shutdown_nb);
1677         return class_register(&firmware_class);
1678 #else
1679         return 0;
1680 #endif
1681 }
1682
1683 static void __exit firmware_class_exit(void)
1684 {
1685 #ifdef CONFIG_PM_SLEEP
1686         unregister_syscore_ops(&fw_syscore_ops);
1687         unregister_pm_notifier(&fw_cache.pm_notify);
1688 #endif
1689 #ifdef CONFIG_FW_LOADER_USER_HELPER
1690         unregister_reboot_notifier(&fw_shutdown_nb);
1691         class_unregister(&firmware_class);
1692 #endif
1693 }
1694
1695 fs_initcall(firmware_class_init);
1696 module_exit(firmware_class_exit);