drivers/base/firmware_loader/main.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  * main.c - Multi purpose firmware loading support
   4  *
   5  * Copyright (c) 2003 Manuel Estrada Sainz
   6  *
   7  * Please see Documentation/driver-api/firmware/ for more information.
   8  *
   9  */
  10
  11 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  12
  13 #include <linux/capability.h>
  14 #include <linux/device.h>
  15 #include <linux/module.h>
  16 #include <linux/init.h>
  17 #include <linux/timer.h>
  18 #include <linux/vmalloc.h>
  19 #include <linux/interrupt.h>
  20 #include <linux/bitops.h>
  21 #include <linux/mutex.h>
  22 #include <linux/workqueue.h>
  23 #include <linux/highmem.h>
  24 #include <linux/firmware.h>
  25 #include <linux/slab.h>
  26 #include <linux/sched.h>
  27 #include <linux/file.h>
  28 #include <linux/list.h>
  29 #include <linux/fs.h>
  30 #include <linux/async.h>
  31 #include <linux/pm.h>
  32 #include <linux/suspend.h>
  33 #include <linux/syscore_ops.h>
  34 #include <linux/reboot.h>
  35 #include <linux/security.h>
  36 #include <linux/xz.h>
  37
  38 #include <generated/utsrelease.h>
  39
  40 #include "../base.h"
  41 #include "firmware.h"
  42 #include "fallback.h"
  43
  44 MODULE_AUTHOR("Manuel Estrada Sainz");
  45 MODULE_DESCRIPTION("Multi purpose firmware loading support");
  46 MODULE_LICENSE("GPL");
  47
  48 struct firmware_cache {
  49         /* firmware_buf instance will be added into the below list */
  50         spinlock_t lock;
  51         struct list_head head;
  52         int state;
  53
  54 #ifdef CONFIG_FW_CACHE
  55         /*
  56          * Names of firmware images which have been cached successfully
  57          * will be added into the below list so that device uncache
  58          * helper can trace which firmware images have been cached
  59          * before.
  60          */
  61         spinlock_t name_lock;
  62         struct list_head fw_names;
  63
  64         struct delayed_work work;
  65
  66         struct notifier_block   pm_notify;
  67 #endif
  68 };
  69
  70 struct fw_cache_entry {
  71         struct list_head list;
  72         const char *name;
  73 };
  74
  75 struct fw_name_devm {
  76         unsigned long magic;
  77         const char *name;
  78 };
  79
  80 static inline struct fw_priv *to_fw_priv(struct kref *ref)
  81 {
  82         return container_of(ref, struct fw_priv, ref);
  83 }
  84
  85 #define FW_LOADER_NO_CACHE      0
  86 #define FW_LOADER_START_CACHE   1
  87
  88 /* fw_lock could be moved to 'struct fw_sysfs' but since it is just
  89  * guarding for corner cases a global lock should be OK */
  90 DEFINE_MUTEX(fw_lock);
  91
  92 static struct firmware_cache fw_cache;
  93
  94 /* Builtin firmware support */
  95
  96 #ifdef CONFIG_FW_LOADER
  97
  98 extern struct builtin_fw __start_builtin_fw[];
  99 extern struct builtin_fw __end_builtin_fw[];
 100
 101 static void fw_copy_to_prealloc_buf(struct firmware *fw,
 102                                     void *buf, size_t size)
 103 {
 104         if (!buf || size < fw->size)
 105                 return;
 106         memcpy(buf, fw->data, fw->size);
 107 }
 108
 109 static bool fw_get_builtin_firmware(struct firmware *fw, const char *name,
 110                                     void *buf, size_t size)
 111 {
 112         struct builtin_fw *b_fw;
 113
 114         for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++) {
 115                 if (strcmp(name, b_fw->name) == 0) {
 116                         fw->size = b_fw->size;
 117                         fw->data = b_fw->data;
 118                         fw_copy_to_prealloc_buf(fw, buf, size);
 119
 120                         return true;
 121                 }
 122         }
 123
 124         return false;
 125 }
 126
 127 static bool fw_is_builtin_firmware(const struct firmware *fw)
 128 {
 129         struct builtin_fw *b_fw;
 130
 131         for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++)
 132                 if (fw->data == b_fw->data)
 133                         return true;
 134
 135         return false;
 136 }
 137
 138 #else /* Module case - no builtin firmware support */
 139
 140 static inline bool fw_get_builtin_firmware(struct firmware *fw,
 141                                            const char *name, void *buf,
 142                                            size_t size)
 143 {
 144         return false;
 145 }
 146
 147 static inline bool fw_is_builtin_firmware(const struct firmware *fw)
 148 {
 149         return false;
 150 }
 151 #endif
 152
 153 static void fw_state_init(struct fw_priv *fw_priv)
 154 {
 155         struct fw_state *fw_st = &fw_priv->fw_st;
 156
 157         init_completion(&fw_st->completion);
 158         fw_st->status = FW_STATUS_UNKNOWN;
 159 }
 160
 161 static inline int fw_state_wait(struct fw_priv *fw_priv)
 162 {
 163         return __fw_state_wait_common(fw_priv, MAX_SCHEDULE_TIMEOUT);
 164 }
 165
 166 static int fw_cache_piggyback_on_request(const char *name);
 167
 168 static struct fw_priv *__allocate_fw_priv(const char *fw_name,
 169                                           struct firmware_cache *fwc,
 170                                           void *dbuf, size_t size)
 171 {
 172         struct fw_priv *fw_priv;
 173
 174         fw_priv = kzalloc(sizeof(*fw_priv), GFP_ATOMIC);
 175         if (!fw_priv)
 176                 return NULL;
 177
 178         fw_priv->fw_name = kstrdup_const(fw_name, GFP_ATOMIC);
 179         if (!fw_priv->fw_name) {
 180                 kfree(fw_priv);
 181                 return NULL;
 182         }
 183
 184         kref_init(&fw_priv->ref);
 185         fw_priv->fwc = fwc;
 186         fw_priv->data = dbuf;
 187         fw_priv->allocated_size = size;
 188         fw_state_init(fw_priv);
 189 #ifdef CONFIG_FW_LOADER_USER_HELPER
 190         INIT_LIST_HEAD(&fw_priv->pending_list);
 191 #endif
 192
 193         pr_debug("%s: fw-%s fw_priv=%p\n", __func__, fw_name, fw_priv);
 194
 195         return fw_priv;
 196 }
 197
 198 static struct fw_priv *__lookup_fw_priv(const char *fw_name)
 199 {
 200         struct fw_priv *tmp;
 201         struct firmware_cache *fwc = &fw_cache;
 202
 203         list_for_each_entry(tmp, &fwc->head, list)
 204                 if (!strcmp(tmp->fw_name, fw_name))
 205                         return tmp;
 206         return NULL;
 207 }
 208
 209 /* Returns 1 for batching firmware requests with the same name */
 210 static int alloc_lookup_fw_priv(const char *fw_name,
 211                                 struct firmware_cache *fwc,
 212                                 struct fw_priv **fw_priv, void *dbuf,
 213                                 size_t size, u32 opt_flags)
 214 {
 215         struct fw_priv *tmp;
 216
 217         spin_lock(&fwc->lock);
 218         if (!(opt_flags & FW_OPT_NOCACHE)) {
 219                 tmp = __lookup_fw_priv(fw_name);
 220                 if (tmp) {
 221                         kref_get(&tmp->ref);
 222                         spin_unlock(&fwc->lock);
 223                         *fw_priv = tmp;
 224                         pr_debug("batched request - sharing the same struct fw_priv and lookup for multiple requests\n");
 225                         return 1;
 226                 }
 227         }
 228
 229         tmp = __allocate_fw_priv(fw_name, fwc, dbuf, size);
 230         if (tmp) {
 231                 INIT_LIST_HEAD(&tmp->list);
 232                 if (!(opt_flags & FW_OPT_NOCACHE))
 233                         list_add(&tmp->list, &fwc->head);
 234         }
 235         spin_unlock(&fwc->lock);
 236
 237         *fw_priv = tmp;
 238
 239         return tmp ? 0 : -ENOMEM;
 240 }
 241
 242 static void __free_fw_priv(struct kref *ref)
 243         __releases(&fwc->lock)
 244 {
 245         struct fw_priv *fw_priv = to_fw_priv(ref);
 246         struct firmware_cache *fwc = fw_priv->fwc;
 247
 248         pr_debug("%s: fw-%s fw_priv=%p data=%p size=%u\n",
 249                  __func__, fw_priv->fw_name, fw_priv, fw_priv->data,
 250                  (unsigned int)fw_priv->size);
 251
 252         list_del(&fw_priv->list);
 253         spin_unlock(&fwc->lock);
 254
 255         if (fw_is_paged_buf(fw_priv))
 256                 fw_free_paged_buf(fw_priv);
 257         else if (!fw_priv->allocated_size)
 258                 vfree(fw_priv->data);
 259
 260         kfree_const(fw_priv->fw_name);
 261         kfree(fw_priv);
 262 }
 263
 264 static void free_fw_priv(struct fw_priv *fw_priv)
 265 {
 266         struct firmware_cache *fwc = fw_priv->fwc;
 267         spin_lock(&fwc->lock);
 268         if (!kref_put(&fw_priv->ref, __free_fw_priv))
 269                 spin_unlock(&fwc->lock);
 270 }
 271
 272 #ifdef CONFIG_FW_LOADER_PAGED_BUF
 273 bool fw_is_paged_buf(struct fw_priv *fw_priv)
 274 {
 275         return fw_priv->is_paged_buf;
 276 }
 277
 278 void fw_free_paged_buf(struct fw_priv *fw_priv)
 279 {
 280         int i;
 281
 282         if (!fw_priv->pages)
 283                 return;
 284
 285         vunmap(fw_priv->data);
 286
 287         for (i = 0; i < fw_priv->nr_pages; i++)
 288                 __free_page(fw_priv->pages[i]);
 289         kvfree(fw_priv->pages);
 290         fw_priv->pages = NULL;
 291         fw_priv->page_array_size = 0;
 292         fw_priv->nr_pages = 0;
 293 }
 294
 295 int fw_grow_paged_buf(struct fw_priv *fw_priv, int pages_needed)
 296 {
 297         /* If the array of pages is too small, grow it */
 298         if (fw_priv->page_array_size < pages_needed) {
 299                 int new_array_size = max(pages_needed,
 300                                          fw_priv->page_array_size * 2);
 301                 struct page **new_pages;
 302
 303                 new_pages = kvmalloc_array(new_array_size, sizeof(void *),
 304                                            GFP_KERNEL);
 305                 if (!new_pages)
 306                         return -ENOMEM;
 307                 memcpy(new_pages, fw_priv->pages,
 308                        fw_priv->page_array_size * sizeof(void *));
 309                 memset(&new_pages[fw_priv->page_array_size], 0, sizeof(void *) *
 310                        (new_array_size - fw_priv->page_array_size));
 311                 kvfree(fw_priv->pages);
 312                 fw_priv->pages = new_pages;
 313                 fw_priv->page_array_size = new_array_size;
 314         }
 315
 316         while (fw_priv->nr_pages < pages_needed) {
 317                 fw_priv->pages[fw_priv->nr_pages] =
 318                         alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
 319
 320                 if (!fw_priv->pages[fw_priv->nr_pages])
 321                         return -ENOMEM;
 322                 fw_priv->nr_pages++;
 323         }
 324
 325         return 0;
 326 }
 327
 328 int fw_map_paged_buf(struct fw_priv *fw_priv)
 329 {
 330         /* one pages buffer should be mapped/unmapped only once */
 331         if (!fw_priv->pages)
 332                 return 0;
 333
 334         vunmap(fw_priv->data);
 335         fw_priv->data = vmap(fw_priv->pages, fw_priv->nr_pages, 0,
 336                              PAGE_KERNEL_RO);
 337         if (!fw_priv->data)
 338                 return -ENOMEM;
 339
 340         return 0;
 341 }
 342 #endif
 343
 344 /*
 345  * XZ-compressed firmware support
 346  */
 347 #ifdef CONFIG_FW_LOADER_COMPRESS
 348 /* show an error and return the standard error code */
 349 static int fw_decompress_xz_error(struct device *dev, enum xz_ret xz_ret)
 350 {
 351         if (xz_ret != XZ_STREAM_END) {
 352                 dev_warn(dev, "xz decompression failed (xz_ret=%d)\n", xz_ret);
 353                 return xz_ret == XZ_MEM_ERROR ? -ENOMEM : -EINVAL;
 354         }
 355         return 0;
 356 }
 357
 358 /* single-shot decompression onto the pre-allocated buffer */
 359 static int fw_decompress_xz_single(struct device *dev, struct fw_priv *fw_priv,
 360                                    size_t in_size, const void *in_buffer)
 361 {
 362         struct xz_dec *xz_dec;
 363         struct xz_buf xz_buf;
 364         enum xz_ret xz_ret;
 365
 366         xz_dec = xz_dec_init(XZ_SINGLE, (u32)-1);
 367         if (!xz_dec)
 368                 return -ENOMEM;
 369
 370         xz_buf.in_size = in_size;
 371         xz_buf.in = in_buffer;
 372         xz_buf.in_pos = 0;
 373         xz_buf.out_size = fw_priv->allocated_size;
 374         xz_buf.out = fw_priv->data;
 375         xz_buf.out_pos = 0;
 376
 377         xz_ret = xz_dec_run(xz_dec, &xz_buf);
 378         xz_dec_end(xz_dec);
 379
 380         fw_priv->size = xz_buf.out_pos;
 381         return fw_decompress_xz_error(dev, xz_ret);
 382 }
 383
 384 /* decompression on paged buffer and map it */
 385 static int fw_decompress_xz_pages(struct device *dev, struct fw_priv *fw_priv,
 386                                   size_t in_size, const void *in_buffer)
 387 {
 388         struct xz_dec *xz_dec;
 389         struct xz_buf xz_buf;
 390         enum xz_ret xz_ret;
 391         struct page *page;
 392         int err = 0;
 393
 394         xz_dec = xz_dec_init(XZ_DYNALLOC, (u32)-1);
 395         if (!xz_dec)
 396                 return -ENOMEM;
 397
 398         xz_buf.in_size = in_size;
 399         xz_buf.in = in_buffer;
 400         xz_buf.in_pos = 0;
 401
 402         fw_priv->is_paged_buf = true;
 403         fw_priv->size = 0;
 404         do {
 405                 if (fw_grow_paged_buf(fw_priv, fw_priv->nr_pages + 1)) {
 406                         err = -ENOMEM;
 407                         goto out;
 408                 }
 409
 410                 /* decompress onto the new allocated page */
 411                 page = fw_priv->pages[fw_priv->nr_pages - 1];
 412                 xz_buf.out = kmap(page);
 413                 xz_buf.out_pos = 0;
 414                 xz_buf.out_size = PAGE_SIZE;
 415                 xz_ret = xz_dec_run(xz_dec, &xz_buf);
 416                 kunmap(page);
 417                 fw_priv->size += xz_buf.out_pos;
 418                 /* partial decompression means either end or error */
 419                 if (xz_buf.out_pos != PAGE_SIZE)
 420                         break;
 421         } while (xz_ret == XZ_OK);
 422
 423         err = fw_decompress_xz_error(dev, xz_ret);
 424         if (!err)
 425                 err = fw_map_paged_buf(fw_priv);
 426
 427  out:
 428         xz_dec_end(xz_dec);
 429         return err;
 430 }
 431
 432 static int fw_decompress_xz(struct device *dev, struct fw_priv *fw_priv,
 433                             size_t in_size, const void *in_buffer)
 434 {
 435         /* if the buffer is pre-allocated, we can perform in single-shot mode */
 436         if (fw_priv->data)
 437                 return fw_decompress_xz_single(dev, fw_priv, in_size, in_buffer);
 438         else
 439                 return fw_decompress_xz_pages(dev, fw_priv, in_size, in_buffer);
 440 }
 441 #endif /* CONFIG_FW_LOADER_COMPRESS */
 442
 443 /* direct firmware loading support */
 444 static char fw_path_para[256];
 445 static const char * const fw_path[] = {
 446         fw_path_para,
 447         "/lib/firmware/updates/" UTS_RELEASE,
 448         "/lib/firmware/updates",
 449         "/lib/firmware/" UTS_RELEASE,
 450         "/lib/firmware"
 451 };
 452
 453 /*
 454  * Typical usage is that passing 'firmware_class.path=$CUSTOMIZED_PATH'
 455  * from kernel command line because firmware_class is generally built in
 456  * kernel instead of module.
 457  */
 458 module_param_string(path, fw_path_para, sizeof(fw_path_para), 0644);
 459 MODULE_PARM_DESC(path, "customized firmware image search path with a higher priority than default path");
 460
 461 static int
 462 fw_get_filesystem_firmware(struct device *device, struct fw_priv *fw_priv,
 463                            const char *suffix,
 464                            int (*decompress)(struct device *dev,
 465                                              struct fw_priv *fw_priv,
 466                                              size_t in_size,
 467                                              const void *in_buffer))
 468 {
 469         loff_t size;
 470         int i, len;
 471         int rc = -ENOENT;
 472         char *path;
 473         size_t msize = INT_MAX;
 474         void *buffer = NULL;
 475
 476         /* Already populated data member means we're loading into a buffer */
 477         if (!decompress && fw_priv->data) {
 478                 buffer = fw_priv->data;
 479                 msize = fw_priv->allocated_size;
 480         }
 481
 482         path = __getname();
 483         if (!path)
 484                 return -ENOMEM;
 485
 486         for (i = 0; i < ARRAY_SIZE(fw_path); i++) {
 487                 /* skip the unset customized path */
 488                 if (!fw_path[i][0])
 489                         continue;
 490
 491                 len = snprintf(path, PATH_MAX, "%s/%s%s",
 492                                fw_path[i], fw_priv->fw_name, suffix);
 493                 if (len >= PATH_MAX) {
 494                         rc = -ENAMETOOLONG;
 495                         break;
 496                 }
 497
 498                 fw_priv->size = 0;
 499
 500                 /* load firmware files from the mount namespace of init */
 501                 rc = kernel_read_file_from_path_initns(path, &buffer,
 502                                                        &size, msize,
 503                                                        READING_FIRMWARE);
 504                 if (rc) {
 505                         if (rc != -ENOENT)
 506                                 dev_warn(device, "loading %s failed with error %d\n",
 507                                          path, rc);
 508                         else
 509                                 dev_dbg(device, "loading %s failed for no such file or directory.\n",
 510                                          path);
 511                         continue;
 512                 }
 513                 dev_dbg(device, "Loading firmware from %s\n", path);
 514                 if (decompress) {
 515                         dev_dbg(device, "f/w decompressing %s\n",
 516                                 fw_priv->fw_name);
 517                         rc = decompress(device, fw_priv, size, buffer);
 518                         /* discard the superfluous original content */
 519                         vfree(buffer);
 520                         buffer = NULL;
 521                         if (rc) {
 522                                 fw_free_paged_buf(fw_priv);
 523                                 continue;
 524                         }
 525                 } else {
 526                         dev_dbg(device, "direct-loading %s\n",
 527                                 fw_priv->fw_name);
 528                         if (!fw_priv->data)
 529                                 fw_priv->data = buffer;
 530                         fw_priv->size = size;
 531                 }
 532                 fw_state_done(fw_priv);
 533                 break;
 534         }
 535         __putname(path);
 536
 537         return rc;
 538 }
 539
 540 /* firmware holds the ownership of pages */
 541 static void firmware_free_data(const struct firmware *fw)
 542 {
 543         /* Loaded directly? */
 544         if (!fw->priv) {
 545                 vfree(fw->data);
 546                 return;
 547         }
 548         free_fw_priv(fw->priv);
 549 }
 550
 551 /* store the pages buffer info firmware from buf */
 552 static void fw_set_page_data(struct fw_priv *fw_priv, struct firmware *fw)
 553 {
 554         fw->priv = fw_priv;
 555         fw->size = fw_priv->size;
 556         fw->data = fw_priv->data;
 557
 558         pr_debug("%s: fw-%s fw_priv=%p data=%p size=%u\n",
 559                  __func__, fw_priv->fw_name, fw_priv, fw_priv->data,
 560                  (unsigned int)fw_priv->size);
 561 }
 562
 563 #ifdef CONFIG_FW_CACHE
 564 static void fw_name_devm_release(struct device *dev, void *res)
 565 {
 566         struct fw_name_devm *fwn = res;
 567
 568         if (fwn->magic == (unsigned long)&fw_cache)
 569                 pr_debug("%s: fw_name-%s devm-%p released\n",
 570                                 __func__, fwn->name, res);
 571         kfree_const(fwn->name);
 572 }
 573
 574 static int fw_devm_match(struct device *dev, void *res,
 575                 void *match_data)
 576 {
 577         struct fw_name_devm *fwn = res;
 578
 579         return (fwn->magic == (unsigned long)&fw_cache) &&
 580                 !strcmp(fwn->name, match_data);
 581 }
 582
 583 static struct fw_name_devm *fw_find_devm_name(struct device *dev,
 584                 const char *name)
 585 {
 586         struct fw_name_devm *fwn;
 587
 588         fwn = devres_find(dev, fw_name_devm_release,
 589                           fw_devm_match, (void *)name);
 590         return fwn;
 591 }
 592
 593 static bool fw_cache_is_setup(struct device *dev, const char *name)
 594 {
 595         struct fw_name_devm *fwn;
 596
 597         fwn = fw_find_devm_name(dev, name);
 598         if (fwn)
 599                 return true;
 600
 601         return false;
 602 }
 603
 604 /* add firmware name into devres list */
 605 static int fw_add_devm_name(struct device *dev, const char *name)
 606 {
 607         struct fw_name_devm *fwn;
 608
 609         if (fw_cache_is_setup(dev, name))
 610                 return 0;
 611
 612         fwn = devres_alloc(fw_name_devm_release, sizeof(struct fw_name_devm),
 613                            GFP_KERNEL);
 614         if (!fwn)
 615                 return -ENOMEM;
 616         fwn->name = kstrdup_const(name, GFP_KERNEL);
 617         if (!fwn->name) {
 618                 devres_free(fwn);
 619                 return -ENOMEM;
 620         }
 621
 622         fwn->magic = (unsigned long)&fw_cache;
 623         devres_add(dev, fwn);
 624
 625         return 0;
 626 }
 627 #else
 628 static bool fw_cache_is_setup(struct device *dev, const char *name)
 629 {
 630         return false;
 631 }
 632
 633 static int fw_add_devm_name(struct device *dev, const char *name)
 634 {
 635         return 0;
 636 }
 637 #endif
 638
 639 int assign_fw(struct firmware *fw, struct device *device, u32 opt_flags)
 640 {
 641         struct fw_priv *fw_priv = fw->priv;
 642         int ret;
 643
 644         mutex_lock(&fw_lock);
 645         if (!fw_priv->size || fw_state_is_aborted(fw_priv)) {
 646                 mutex_unlock(&fw_lock);
 647                 return -ENOENT;
 648         }
 649
 650         /*
 651          * add firmware name into devres list so that we can auto cache
 652          * and uncache firmware for device.
 653          *
 654          * device may has been deleted already, but the problem
 655          * should be fixed in devres or driver core.
 656          */
 657         /* don't cache firmware handled without uevent */
 658         if (device && (opt_flags & FW_OPT_UEVENT) &&
 659             !(opt_flags & FW_OPT_NOCACHE)) {
 660                 ret = fw_add_devm_name(device, fw_priv->fw_name);
 661                 if (ret) {
 662                         mutex_unlock(&fw_lock);
 663                         return ret;
 664                 }
 665         }
 666
 667         /*
 668          * After caching firmware image is started, let it piggyback
 669          * on request firmware.
 670          */
 671         if (!(opt_flags & FW_OPT_NOCACHE) &&
 672             fw_priv->fwc->state == FW_LOADER_START_CACHE) {
 673                 if (fw_cache_piggyback_on_request(fw_priv->fw_name))
 674                         kref_get(&fw_priv->ref);
 675         }
 676
 677         /* pass the pages buffer to driver at the last minute */
 678         fw_set_page_data(fw_priv, fw);
 679         mutex_unlock(&fw_lock);
 680         return 0;
 681 }
 682
 683 /* prepare firmware and firmware_buf structs;
 684  * return 0 if a firmware is already assigned, 1 if need to load one,
 685  * or a negative error code
 686  */
 687 static int
 688 _request_firmware_prepare(struct firmware **firmware_p, const char *name,
 689                           struct device *device, void *dbuf, size_t size,
 690                           u32 opt_flags)
 691 {
 692         struct firmware *firmware;
 693         struct fw_priv *fw_priv;
 694         int ret;
 695
 696         *firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
 697         if (!firmware) {
 698                 dev_err(device, "%s: kmalloc(struct firmware) failed\n",
 699                         __func__);
 700                 return -ENOMEM;
 701         }
 702
 703         if (fw_get_builtin_firmware(firmware, name, dbuf, size)) {
 704                 dev_dbg(device, "using built-in %s\n", name);
 705                 return 0; /* assigned */
 706         }
 707
 708         ret = alloc_lookup_fw_priv(name, &fw_cache, &fw_priv, dbuf, size,
 709                                   opt_flags);
 710
 711         /*
 712          * bind with 'priv' now to avoid warning in failure path
 713          * of requesting firmware.
 714          */
 715         firmware->priv = fw_priv;
 716
 717         if (ret > 0) {
 718                 ret = fw_state_wait(fw_priv);
 719                 if (!ret) {
 720                         fw_set_page_data(fw_priv, firmware);
 721                         return 0; /* assigned */
 722                 }
 723         }
 724
 725         if (ret < 0)
 726                 return ret;
 727         return 1; /* need to load */
 728 }
 729
 730 /*
 731  * Batched requests need only one wake, we need to do this step last due to the
 732  * fallback mechanism. The buf is protected with kref_get(), and it won't be
 733  * released until the last user calls release_firmware().
 734  *
 735  * Failed batched requests are possible as well, in such cases we just share
 736  * the struct fw_priv and won't release it until all requests are woken
 737  * and have gone through this same path.
 738  */
 739 static void fw_abort_batch_reqs(struct firmware *fw)
 740 {
 741         struct fw_priv *fw_priv;
 742
 743         /* Loaded directly? */
 744         if (!fw || !fw->priv)
 745                 return;
 746
 747         fw_priv = fw->priv;
 748         if (!fw_state_is_aborted(fw_priv))
 749                 fw_state_aborted(fw_priv);
 750 }
 751
 752 /* called from request_firmware() and request_firmware_work_func() */
 753 static int
 754 _request_firmware(const struct firmware **firmware_p, const char *name,
 755                   struct device *device, void *buf, size_t size,
 756                   u32 opt_flags)
 757 {
 758         struct firmware *fw = NULL;
 759         int ret;
 760
 761         if (!firmware_p)
 762                 return -EINVAL;
 763
 764         if (!name || name[0] == '\0') {
 765                 ret = -EINVAL;
 766                 goto out;
 767         }
 768
 769         ret = _request_firmware_prepare(&fw, name, device, buf, size,
 770                                         opt_flags);
 771         if (ret <= 0) /* error or already assigned */
 772                 goto out;
 773
 774         ret = fw_get_filesystem_firmware(device, fw->priv, "", NULL);
 775 #ifdef CONFIG_FW_LOADER_COMPRESS
 776         if (ret == -ENOENT)
 777                 ret = fw_get_filesystem_firmware(device, fw->priv, ".xz",
 778                                                  fw_decompress_xz);
 779 #endif
 780
 781         if (ret == -ENOENT)
 782                 ret = firmware_fallback_platform(fw->priv, opt_flags);
 783
 784         if (ret) {
 785                 if (!(opt_flags & FW_OPT_NO_WARN))
 786                         dev_warn(device,
 787                                  "Direct firmware load for %s failed with error %d\n",
 788                                  name, ret);
 789                 ret = firmware_fallback_sysfs(fw, name, device, opt_flags, ret);
 790         } else
 791                 ret = assign_fw(fw, device, opt_flags);
 792
 793  out:
 794         if (ret < 0) {
 795                 fw_abort_batch_reqs(fw);
 796                 release_firmware(fw);
 797                 fw = NULL;
 798         }
 799
 800         *firmware_p = fw;
 801         return ret;
 802 }
 803
 804 /**
 805  * request_firmware() - send firmware request and wait for it
 806  * @firmware_p: pointer to firmware image
 807  * @name: name of firmware file
 808  * @device: device for which firmware is being loaded
 809  *
 810  *      @firmware_p will be used to return a firmware image by the name
 811  *      of @name for device @device.
 812  *
 813  *      Should be called from user context where sleeping is allowed.
 814  *
 815  *      @name will be used as $FIRMWARE in the uevent environment and
 816  *      should be distinctive enough not to be confused with any other
 817  *      firmware image for this or any other device.
 818  *
 819  *      Caller must hold the reference count of @device.
 820  *
 821  *      The function can be called safely inside device's suspend and
 822  *      resume callback.
 823  **/
 824 int
 825 request_firmware(const struct firmware **firmware_p, const char *name,
 826                  struct device *device)
 827 {
 828         int ret;
 829
 830         /* Need to pin this module until return */
 831         __module_get(THIS_MODULE);
 832         ret = _request_firmware(firmware_p, name, device, NULL, 0,
 833                                 FW_OPT_UEVENT);
 834         module_put(THIS_MODULE);
 835         return ret;
 836 }
 837 EXPORT_SYMBOL(request_firmware);
 838
 839 /**
 840  * firmware_request_nowarn() - request for an optional fw module
 841  * @firmware: pointer to firmware image
 842  * @name: name of firmware file
 843  * @device: device for which firmware is being loaded
 844  *
 845  * This function is similar in behaviour to request_firmware(), except it
 846  * doesn't produce warning messages when the file is not found. The sysfs
 847  * fallback mechanism is enabled if direct filesystem lookup fails. However,
 848  * failures to find the firmware file with it are still suppressed. It is
 849  * therefore up to the driver to check for the return value of this call and to
 850  * decide when to inform the users of errors.
 851  **/
 852 int firmware_request_nowarn(const struct firmware **firmware, const char *name,
 853                             struct device *device)
 854 {
 855         int ret;
 856
 857         /* Need to pin this module until return */
 858         __module_get(THIS_MODULE);
 859         ret = _request_firmware(firmware, name, device, NULL, 0,
 860                                 FW_OPT_UEVENT | FW_OPT_NO_WARN);
 861         module_put(THIS_MODULE);
 862         return ret;
 863 }
 864 EXPORT_SYMBOL_GPL(firmware_request_nowarn);
 865
 866 /**
 867  * request_firmware_direct() - load firmware directly without usermode helper
 868  * @firmware_p: pointer to firmware image
 869  * @name: name of firmware file
 870  * @device: device for which firmware is being loaded
 871  *
 872  * This function works pretty much like request_firmware(), but this doesn't
 873  * fall back to usermode helper even if the firmware couldn't be loaded
 874  * directly from fs.  Hence it's useful for loading optional firmwares, which
 875  * aren't always present, without extra long timeouts of udev.
 876  **/
 877 int request_firmware_direct(const struct firmware **firmware_p,
 878                             const char *name, struct device *device)
 879 {
 880         int ret;
 881
 882         __module_get(THIS_MODULE);
 883         ret = _request_firmware(firmware_p, name, device, NULL, 0,
 884                                 FW_OPT_UEVENT | FW_OPT_NO_WARN |
 885                                 FW_OPT_NOFALLBACK_SYSFS);
 886         module_put(THIS_MODULE);
 887         return ret;
 888 }
 889 EXPORT_SYMBOL_GPL(request_firmware_direct);
 890
 891 /**
 892  * firmware_request_platform() - request firmware with platform-fw fallback
 893  * @firmware: pointer to firmware image
 894  * @name: name of firmware file
 895  * @device: device for which firmware is being loaded
 896  *
 897  * This function is similar in behaviour to request_firmware, except that if
 898  * direct filesystem lookup fails, it will fallback to looking for a copy of the
 899  * requested firmware embedded in the platform's main (e.g. UEFI) firmware.
 900  **/
 901 int firmware_request_platform(const struct firmware **firmware,
 902                               const char *name, struct device *device)
 903 {
 904         int ret;
 905
 906         /* Need to pin this module until return */
 907         __module_get(THIS_MODULE);
 908         ret = _request_firmware(firmware, name, device, NULL, 0,
 909                                 FW_OPT_UEVENT | FW_OPT_FALLBACK_PLATFORM);
 910         module_put(THIS_MODULE);
 911         return ret;
 912 }
 913 EXPORT_SYMBOL_GPL(firmware_request_platform);
 914
 915 /**
 916  * firmware_request_cache() - cache firmware for suspend so resume can use it
 917  * @name: name of firmware file
 918  * @device: device for which firmware should be cached for
 919  *
 920  * There are some devices with an optimization that enables the device to not
 921  * require loading firmware on system reboot. This optimization may still
 922  * require the firmware present on resume from suspend. This routine can be
 923  * used to ensure the firmware is present on resume from suspend in these
 924  * situations. This helper is not compatible with drivers which use
 925  * request_firmware_into_buf() or request_firmware_nowait() with no uevent set.
 926  **/
 927 int firmware_request_cache(struct device *device, const char *name)
 928 {
 929         int ret;
 930
 931         mutex_lock(&fw_lock);
 932         ret = fw_add_devm_name(device, name);
 933         mutex_unlock(&fw_lock);
 934
 935         return ret;
 936 }
 937 EXPORT_SYMBOL_GPL(firmware_request_cache);
 938
 939 /**
 940  * request_firmware_into_buf() - load firmware into a previously allocated buffer
 941  * @firmware_p: pointer to firmware image
 942  * @name: name of firmware file
 943  * @device: device for which firmware is being loaded and DMA region allocated
 944  * @buf: address of buffer to load firmware into
 945  * @size: size of buffer
 946  *
 947  * This function works pretty much like request_firmware(), but it doesn't
 948  * allocate a buffer to hold the firmware data. Instead, the firmware
 949  * is loaded directly into the buffer pointed to by @buf and the @firmware_p
 950  * data member is pointed at @buf.
 951  *
 952  * This function doesn't cache firmware either.
 953  */
 954 int
 955 request_firmware_into_buf(const struct firmware **firmware_p, const char *name,
 956                           struct device *device, void *buf, size_t size)
 957 {
 958         int ret;
 959
 960         if (fw_cache_is_setup(device, name))
 961                 return -EOPNOTSUPP;
 962
 963         __module_get(THIS_MODULE);
 964         ret = _request_firmware(firmware_p, name, device, buf, size,
 965                                 FW_OPT_UEVENT | FW_OPT_NOCACHE);
 966         module_put(THIS_MODULE);
 967         return ret;
 968 }
 969 EXPORT_SYMBOL(request_firmware_into_buf);
 970
 971 /**
 972  * release_firmware() - release the resource associated with a firmware image
 973  * @fw: firmware resource to release
 974  **/
 975 void release_firmware(const struct firmware *fw)
 976 {
 977         if (fw) {
 978                 if (!fw_is_builtin_firmware(fw))
 979                         firmware_free_data(fw);
 980                 kfree(fw);
 981         }
 982 }
 983 EXPORT_SYMBOL(release_firmware);
 984
 985 /* Async support */
 986 struct firmware_work {
 987         struct work_struct work;
 988         struct module *module;
 989         const char *name;
 990         struct device *device;
 991         void *context;
 992         void (*cont)(const struct firmware *fw, void *context);
 993         u32 opt_flags;
 994 };
 995
 996 static void request_firmware_work_func(struct work_struct *work)
 997 {
 998         struct firmware_work *fw_work;
 999         const struct firmware *fw;
1000
1001         fw_work = container_of(work, struct firmware_work, work);
1002
1003         _request_firmware(&fw, fw_work->name, fw_work->device, NULL, 0,
1004                           fw_work->opt_flags);
1005         fw_work->cont(fw, fw_work->context);
1006         put_device(fw_work->device); /* taken in request_firmware_nowait() */
1007
1008         module_put(fw_work->module);
1009         kfree_const(fw_work->name);
1010         kfree(fw_work);
1011 }
1012
1013 /**
1014  * request_firmware_nowait() - asynchronous version of request_firmware
1015  * @module: module requesting the firmware
1016  * @uevent: sends uevent to copy the firmware image if this flag
1017  *      is non-zero else the firmware copy must be done manually.
1018  * @name: name of firmware file
1019  * @device: device for which firmware is being loaded
1020  * @gfp: allocation flags
1021  * @context: will be passed over to @cont, and
1022  *      @fw may be %NULL if firmware request fails.
1023  * @cont: function will be called asynchronously when the firmware
1024  *      request is over.
1025  *
1026  *      Caller must hold the reference count of @device.
1027  *
1028  *      Asynchronous variant of request_firmware() for user contexts:
1029  *              - sleep for as small periods as possible since it may
1030  *                increase kernel boot time of built-in device drivers
1031  *                requesting firmware in their ->probe() methods, if
1032  *                @gfp is GFP_KERNEL.
1033  *
1034  *              - can't sleep at all if @gfp is GFP_ATOMIC.
1035  **/
1036 int
1037 request_firmware_nowait(
1038         struct module *module, bool uevent,
1039         const char *name, struct device *device, gfp_t gfp, void *context,
1040         void (*cont)(const struct firmware *fw, void *context))
1041 {
1042         struct firmware_work *fw_work;
1043
1044         fw_work = kzalloc(sizeof(struct firmware_work), gfp);
1045         if (!fw_work)
1046                 return -ENOMEM;
1047
1048         fw_work->module = module;
1049         fw_work->name = kstrdup_const(name, gfp);
1050         if (!fw_work->name) {
1051                 kfree(fw_work);
1052                 return -ENOMEM;
1053         }
1054         fw_work->device = device;
1055         fw_work->context = context;
1056         fw_work->cont = cont;
1057         fw_work->opt_flags = FW_OPT_NOWAIT |
1058                 (uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER);
1059
1060         if (!uevent && fw_cache_is_setup(device, name)) {
1061                 kfree_const(fw_work->name);
1062                 kfree(fw_work);
1063                 return -EOPNOTSUPP;
1064         }
1065
1066         if (!try_module_get(module)) {
1067                 kfree_const(fw_work->name);
1068                 kfree(fw_work);
1069                 return -EFAULT;
1070         }
1071
1072         get_device(fw_work->device);
1073         INIT_WORK(&fw_work->work, request_firmware_work_func);
1074         schedule_work(&fw_work->work);
1075         return 0;
1076 }
1077 EXPORT_SYMBOL(request_firmware_nowait);
1078
1079 #ifdef CONFIG_FW_CACHE
1080 static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
1081
1082 /**
1083  * cache_firmware() - cache one firmware image in kernel memory space
1084  * @fw_name: the firmware image name
1085  *
1086  * Cache firmware in kernel memory so that drivers can use it when
1087  * system isn't ready for them to request firmware image from userspace.
1088  * Once it returns successfully, driver can use request_firmware or its
1089  * nowait version to get the cached firmware without any interacting
1090  * with userspace
1091  *
1092  * Return 0 if the firmware image has been cached successfully
1093  * Return !0 otherwise
1094  *
1095  */
1096 static int cache_firmware(const char *fw_name)
1097 {
1098         int ret;
1099         const struct firmware *fw;
1100
1101         pr_debug("%s: %s\n", __func__, fw_name);
1102
1103         ret = request_firmware(&fw, fw_name, NULL);
1104         if (!ret)
1105                 kfree(fw);
1106
1107         pr_debug("%s: %s ret=%d\n", __func__, fw_name, ret);
1108
1109         return ret;
1110 }
1111
1112 static struct fw_priv *lookup_fw_priv(const char *fw_name)
1113 {
1114         struct fw_priv *tmp;
1115         struct firmware_cache *fwc = &fw_cache;
1116
1117         spin_lock(&fwc->lock);
1118         tmp = __lookup_fw_priv(fw_name);
1119         spin_unlock(&fwc->lock);
1120
1121         return tmp;
1122 }
1123
1124 /**
1125  * uncache_firmware() - remove one cached firmware image
1126  * @fw_name: the firmware image name
1127  *
1128  * Uncache one firmware image which has been cached successfully
1129  * before.
1130  *
1131  * Return 0 if the firmware cache has been removed successfully
1132  * Return !0 otherwise
1133  *
1134  */
1135 static int uncache_firmware(const char *fw_name)
1136 {
1137         struct fw_priv *fw_priv;
1138         struct firmware fw;
1139
1140         pr_debug("%s: %s\n", __func__, fw_name);
1141
1142         if (fw_get_builtin_firmware(&fw, fw_name, NULL, 0))
1143                 return 0;
1144
1145         fw_priv = lookup_fw_priv(fw_name);
1146         if (fw_priv) {
1147                 free_fw_priv(fw_priv);
1148                 return 0;
1149         }
1150
1151         return -EINVAL;
1152 }
1153
1154 static struct fw_cache_entry *alloc_fw_cache_entry(const char *name)
1155 {
1156         struct fw_cache_entry *fce;
1157
1158         fce = kzalloc(sizeof(*fce), GFP_ATOMIC);
1159         if (!fce)
1160                 goto exit;
1161
1162         fce->name = kstrdup_const(name, GFP_ATOMIC);
1163         if (!fce->name) {
1164                 kfree(fce);
1165                 fce = NULL;
1166                 goto exit;
1167         }
1168 exit:
1169         return fce;
1170 }
1171
1172 static int __fw_entry_found(const char *name)
1173 {
1174         struct firmware_cache *fwc = &fw_cache;
1175         struct fw_cache_entry *fce;
1176
1177         list_for_each_entry(fce, &fwc->fw_names, list) {
1178                 if (!strcmp(fce->name, name))
1179                         return 1;
1180         }
1181         return 0;
1182 }
1183
1184 static int fw_cache_piggyback_on_request(const char *name)
1185 {
1186         struct firmware_cache *fwc = &fw_cache;
1187         struct fw_cache_entry *fce;
1188         int ret = 0;
1189
1190         spin_lock(&fwc->name_lock);
1191         if (__fw_entry_found(name))
1192                 goto found;
1193
1194         fce = alloc_fw_cache_entry(name);
1195         if (fce) {
1196                 ret = 1;
1197                 list_add(&fce->list, &fwc->fw_names);
1198                 pr_debug("%s: fw: %s\n", __func__, name);
1199         }
1200 found:
1201         spin_unlock(&fwc->name_lock);
1202         return ret;
1203 }
1204
1205 static void free_fw_cache_entry(struct fw_cache_entry *fce)
1206 {
1207         kfree_const(fce->name);
1208         kfree(fce);
1209 }
1210
1211 static void __async_dev_cache_fw_image(void *fw_entry,
1212                                        async_cookie_t cookie)
1213 {
1214         struct fw_cache_entry *fce = fw_entry;
1215         struct firmware_cache *fwc = &fw_cache;
1216         int ret;
1217
1218         ret = cache_firmware(fce->name);
1219         if (ret) {
1220                 spin_lock(&fwc->name_lock);
1221                 list_del(&fce->list);
1222                 spin_unlock(&fwc->name_lock);
1223
1224                 free_fw_cache_entry(fce);
1225         }
1226 }
1227
1228 /* called with dev->devres_lock held */
1229 static void dev_create_fw_entry(struct device *dev, void *res,
1230                                 void *data)
1231 {
1232         struct fw_name_devm *fwn = res;
1233         const char *fw_name = fwn->name;
1234         struct list_head *head = data;
1235         struct fw_cache_entry *fce;
1236
1237         fce = alloc_fw_cache_entry(fw_name);
1238         if (fce)
1239                 list_add(&fce->list, head);
1240 }
1241
1242 static int devm_name_match(struct device *dev, void *res,
1243                            void *match_data)
1244 {
1245         struct fw_name_devm *fwn = res;
1246         return (fwn->magic == (unsigned long)match_data);
1247 }
1248
1249 static void dev_cache_fw_image(struct device *dev, void *data)
1250 {
1251         LIST_HEAD(todo);
1252         struct fw_cache_entry *fce;
1253         struct fw_cache_entry *fce_next;
1254         struct firmware_cache *fwc = &fw_cache;
1255
1256         devres_for_each_res(dev, fw_name_devm_release,
1257                             devm_name_match, &fw_cache,
1258                             dev_create_fw_entry, &todo);
1259
1260         list_for_each_entry_safe(fce, fce_next, &todo, list) {
1261                 list_del(&fce->list);
1262
1263                 spin_lock(&fwc->name_lock);
1264                 /* only one cache entry for one firmware */
1265                 if (!__fw_entry_found(fce->name)) {
1266                         list_add(&fce->list, &fwc->fw_names);
1267                 } else {
1268                         free_fw_cache_entry(fce);
1269                         fce = NULL;
1270                 }
1271                 spin_unlock(&fwc->name_lock);
1272
1273                 if (fce)
1274                         async_schedule_domain(__async_dev_cache_fw_image,
1275                                               (void *)fce,
1276                                               &fw_cache_domain);
1277         }
1278 }
1279
1280 static void __device_uncache_fw_images(void)
1281 {
1282         struct firmware_cache *fwc = &fw_cache;
1283         struct fw_cache_entry *fce;
1284
1285         spin_lock(&fwc->name_lock);
1286         while (!list_empty(&fwc->fw_names)) {
1287                 fce = list_entry(fwc->fw_names.next,
1288                                 struct fw_cache_entry, list);
1289                 list_del(&fce->list);
1290                 spin_unlock(&fwc->name_lock);
1291
1292                 uncache_firmware(fce->name);
1293                 free_fw_cache_entry(fce);
1294
1295                 spin_lock(&fwc->name_lock);
1296         }
1297         spin_unlock(&fwc->name_lock);
1298 }
1299
1300 /**
1301  * device_cache_fw_images() - cache devices' firmware
1302  *
1303  * If one device called request_firmware or its nowait version
1304  * successfully before, the firmware names are recored into the
1305  * device's devres link list, so device_cache_fw_images can call
1306  * cache_firmware() to cache these firmwares for the device,
1307  * then the device driver can load its firmwares easily at
1308  * time when system is not ready to complete loading firmware.
1309  */
1310 static void device_cache_fw_images(void)
1311 {
1312         struct firmware_cache *fwc = &fw_cache;
1313         DEFINE_WAIT(wait);
1314
1315         pr_debug("%s\n", __func__);
1316
1317         /* cancel uncache work */
1318         cancel_delayed_work_sync(&fwc->work);
1319
1320         fw_fallback_set_cache_timeout();
1321
1322         mutex_lock(&fw_lock);
1323         fwc->state = FW_LOADER_START_CACHE;
1324         dpm_for_each_dev(NULL, dev_cache_fw_image);
1325         mutex_unlock(&fw_lock);
1326
1327         /* wait for completion of caching firmware for all devices */
1328         async_synchronize_full_domain(&fw_cache_domain);
1329
1330         fw_fallback_set_default_timeout();
1331 }
1332
1333 /**
1334  * device_uncache_fw_images() - uncache devices' firmware
1335  *
1336  * uncache all firmwares which have been cached successfully
1337  * by device_uncache_fw_images earlier
1338  */
1339 static void device_uncache_fw_images(void)
1340 {
1341         pr_debug("%s\n", __func__);
1342         __device_uncache_fw_images();
1343 }
1344
1345 static void device_uncache_fw_images_work(struct work_struct *work)
1346 {
1347         device_uncache_fw_images();
1348 }
1349
1350 /**
1351  * device_uncache_fw_images_delay() - uncache devices firmwares
1352  * @delay: number of milliseconds to delay uncache device firmwares
1353  *
1354  * uncache all devices's firmwares which has been cached successfully
1355  * by device_cache_fw_images after @delay milliseconds.
1356  */
1357 static void device_uncache_fw_images_delay(unsigned long delay)
1358 {
1359         queue_delayed_work(system_power_efficient_wq, &fw_cache.work,
1360                            msecs_to_jiffies(delay));
1361 }
1362
1363 static int fw_pm_notify(struct notifier_block *notify_block,
1364                         unsigned long mode, void *unused)
1365 {
1366         switch (mode) {
1367         case PM_HIBERNATION_PREPARE:
1368         case PM_SUSPEND_PREPARE:
1369         case PM_RESTORE_PREPARE:
1370                 /*
1371                  * kill pending fallback requests with a custom fallback
1372                  * to avoid stalling suspend.
1373                  */
1374                 kill_pending_fw_fallback_reqs(true);
1375                 device_cache_fw_images();
1376                 break;
1377
1378         case PM_POST_SUSPEND:
1379         case PM_POST_HIBERNATION:
1380         case PM_POST_RESTORE:
1381                 /*
1382                  * In case that system sleep failed and syscore_suspend is
1383                  * not called.
1384                  */
1385                 mutex_lock(&fw_lock);
1386                 fw_cache.state = FW_LOADER_NO_CACHE;
1387                 mutex_unlock(&fw_lock);
1388
1389                 device_uncache_fw_images_delay(10 * MSEC_PER_SEC);
1390                 break;
1391         }
1392
1393         return 0;
1394 }
1395
1396 /* stop caching firmware once syscore_suspend is reached */
1397 static int fw_suspend(void)
1398 {
1399         fw_cache.state = FW_LOADER_NO_CACHE;
1400         return 0;
1401 }
1402
1403 static struct syscore_ops fw_syscore_ops = {
1404         .suspend = fw_suspend,
1405 };
1406
1407 static int __init register_fw_pm_ops(void)
1408 {
1409         int ret;
1410
1411         spin_lock_init(&fw_cache.name_lock);
1412         INIT_LIST_HEAD(&fw_cache.fw_names);
1413
1414         INIT_DELAYED_WORK(&fw_cache.work,
1415                           device_uncache_fw_images_work);
1416
1417         fw_cache.pm_notify.notifier_call = fw_pm_notify;
1418         ret = register_pm_notifier(&fw_cache.pm_notify);
1419         if (ret)
1420                 return ret;
1421
1422         register_syscore_ops(&fw_syscore_ops);
1423
1424         return ret;
1425 }
1426
1427 static inline void unregister_fw_pm_ops(void)
1428 {
1429         unregister_syscore_ops(&fw_syscore_ops);
1430         unregister_pm_notifier(&fw_cache.pm_notify);
1431 }
1432 #else
1433 static int fw_cache_piggyback_on_request(const char *name)
1434 {
1435         return 0;
1436 }
1437 static inline int register_fw_pm_ops(void)
1438 {
1439         return 0;
1440 }
1441 static inline void unregister_fw_pm_ops(void)
1442 {
1443 }
1444 #endif
1445
1446 static void __init fw_cache_init(void)
1447 {
1448         spin_lock_init(&fw_cache.lock);
1449         INIT_LIST_HEAD(&fw_cache.head);
1450         fw_cache.state = FW_LOADER_NO_CACHE;
1451 }
1452
1453 static int fw_shutdown_notify(struct notifier_block *unused1,
1454                               unsigned long unused2, void *unused3)
1455 {
1456         /*
1457          * Kill all pending fallback requests to avoid both stalling shutdown,
1458          * and avoid a deadlock with the usermode_lock.
1459          */
1460         kill_pending_fw_fallback_reqs(false);
1461
1462         return NOTIFY_DONE;
1463 }
1464
1465 static struct notifier_block fw_shutdown_nb = {
1466         .notifier_call = fw_shutdown_notify,
1467 };
1468
1469 static int __init firmware_class_init(void)
1470 {
1471         int ret;
1472
1473         /* No need to unfold these on exit */
1474         fw_cache_init();
1475
1476         ret = register_fw_pm_ops();
1477         if (ret)
1478                 return ret;
1479
1480         ret = register_reboot_notifier(&fw_shutdown_nb);
1481         if (ret)
1482                 goto out;
1483
1484         return register_sysfs_loader();
1485
1486 out:
1487         unregister_fw_pm_ops();
1488         return ret;
1489 }
1490
1491 static void __exit firmware_class_exit(void)
1492 {
1493         unregister_fw_pm_ops();
1494         unregister_reboot_notifier(&fw_shutdown_nb);
1495         unregister_sysfs_loader();
1496 }
1497
1498 fs_initcall(firmware_class_init);
1499 module_exit(firmware_class_exit);