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/kernel_read_file.h>
  16 #include <linux/module.h>
  17 #include <linux/init.h>
  18 #include <linux/timer.h>
  19 #include <linux/vmalloc.h>
  20 #include <linux/interrupt.h>
  21 #include <linux/bitops.h>
  22 #include <linux/mutex.h>
  23 #include <linux/workqueue.h>
  24 #include <linux/highmem.h>
  25 #include <linux/firmware.h>
  26 #include <linux/slab.h>
  27 #include <linux/sched.h>
  28 #include <linux/file.h>
  29 #include <linux/list.h>
  30 #include <linux/fs.h>
  31 #include <linux/async.h>
  32 #include <linux/pm.h>
  33 #include <linux/suspend.h>
  34 #include <linux/syscore_ops.h>
  35 #include <linux/reboot.h>
  36 #include <linux/security.h>
  37 #include <linux/xz.h>
  38
  39 #include <generated/utsrelease.h>
  40
  41 #include "../base.h"
  42 #include "firmware.h"
  43 #include "fallback.h"
  44
  45 MODULE_AUTHOR("Manuel Estrada Sainz");
  46 MODULE_DESCRIPTION("Multi purpose firmware loading support");
  47 MODULE_LICENSE("GPL");
  48
  49 struct firmware_cache {
  50         /* firmware_buf instance will be added into the below list */
  51         spinlock_t lock;
  52         struct list_head head;
  53         int state;
  54
  55 #ifdef CONFIG_FW_CACHE
  56         /*
  57          * Names of firmware images which have been cached successfully
  58          * will be added into the below list so that device uncache
  59          * helper can trace which firmware images have been cached
  60          * before.
  61          */
  62         spinlock_t name_lock;
  63         struct list_head fw_names;
  64
  65         struct delayed_work work;
  66
  67         struct notifier_block   pm_notify;
  68 #endif
  69 };
  70
  71 struct fw_cache_entry {
  72         struct list_head list;
  73         const char *name;
  74 };
  75
  76 struct fw_name_devm {
  77         unsigned long magic;
  78         const char *name;
  79 };
  80
  81 static inline struct fw_priv *to_fw_priv(struct kref *ref)
  82 {
  83         return container_of(ref, struct fw_priv, ref);
  84 }
  85
  86 #define FW_LOADER_NO_CACHE      0
  87 #define FW_LOADER_START_CACHE   1
  88
  89 /* fw_lock could be moved to 'struct fw_sysfs' but since it is just
  90  * guarding for corner cases a global lock should be OK */
  91 DEFINE_MUTEX(fw_lock);
  92
  93 static struct firmware_cache fw_cache;
  94
  95 /* Builtin firmware support */
  96
  97 #ifdef CONFIG_FW_LOADER
  98
  99 extern struct builtin_fw __start_builtin_fw[];
 100 extern struct builtin_fw __end_builtin_fw[];
 101
 102 static void fw_copy_to_prealloc_buf(struct firmware *fw,
 103                                     void *buf, size_t size)
 104 {
 105         if (!buf || size < fw->size)
 106                 return;
 107         memcpy(buf, fw->data, fw->size);
 108 }
 109
 110 static bool fw_get_builtin_firmware(struct firmware *fw, const char *name,
 111                                     void *buf, size_t size)
 112 {
 113         struct builtin_fw *b_fw;
 114
 115         for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++) {
 116                 if (strcmp(name, b_fw->name) == 0) {
 117                         fw->size = b_fw->size;
 118                         fw->data = b_fw->data;
 119                         fw_copy_to_prealloc_buf(fw, buf, size);
 120
 121                         return true;
 122                 }
 123         }
 124
 125         return false;
 126 }
 127
 128 static bool fw_is_builtin_firmware(const struct firmware *fw)
 129 {
 130         struct builtin_fw *b_fw;
 131
 132         for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++)
 133                 if (fw->data == b_fw->data)
 134                         return true;
 135
 136         return false;
 137 }
 138
 139 #else /* Module case - no builtin firmware support */
 140
 141 static inline bool fw_get_builtin_firmware(struct firmware *fw,
 142                                            const char *name, void *buf,
 143                                            size_t size)
 144 {
 145         return false;
 146 }
 147
 148 static inline bool fw_is_builtin_firmware(const struct firmware *fw)
 149 {
 150         return false;
 151 }
 152 #endif
 153
 154 static void fw_state_init(struct fw_priv *fw_priv)
 155 {
 156         struct fw_state *fw_st = &fw_priv->fw_st;
 157
 158         init_completion(&fw_st->completion);
 159         fw_st->status = FW_STATUS_UNKNOWN;
 160 }
 161
 162 static inline int fw_state_wait(struct fw_priv *fw_priv)
 163 {
 164         return __fw_state_wait_common(fw_priv, MAX_SCHEDULE_TIMEOUT);
 165 }
 166
 167 static int fw_cache_piggyback_on_request(const char *name);
 168
 169 static struct fw_priv *__allocate_fw_priv(const char *fw_name,
 170                                           struct firmware_cache *fwc,
 171                                           void *dbuf,
 172                                           size_t size,
 173                                           size_t offset,
 174                                           u32 opt_flags)
 175 {
 176         struct fw_priv *fw_priv;
 177
 178         /* For a partial read, the buffer must be preallocated. */
 179         if ((opt_flags & FW_OPT_PARTIAL) && !dbuf)
 180                 return NULL;
 181
 182         /* Only partial reads are allowed to use an offset. */
 183         if (offset != 0 && !(opt_flags & FW_OPT_PARTIAL))
 184                 return NULL;
 185
 186         fw_priv = kzalloc(sizeof(*fw_priv), GFP_ATOMIC);
 187         if (!fw_priv)
 188                 return NULL;
 189
 190         fw_priv->fw_name = kstrdup_const(fw_name, GFP_ATOMIC);
 191         if (!fw_priv->fw_name) {
 192                 kfree(fw_priv);
 193                 return NULL;
 194         }
 195
 196         kref_init(&fw_priv->ref);
 197         fw_priv->fwc = fwc;
 198         fw_priv->data = dbuf;
 199         fw_priv->allocated_size = size;
 200         fw_priv->offset = offset;
 201         fw_priv->opt_flags = opt_flags;
 202         fw_state_init(fw_priv);
 203 #ifdef CONFIG_FW_LOADER_USER_HELPER
 204         INIT_LIST_HEAD(&fw_priv->pending_list);
 205 #endif
 206
 207         pr_debug("%s: fw-%s fw_priv=%p\n", __func__, fw_name, fw_priv);
 208
 209         return fw_priv;
 210 }
 211
 212 static struct fw_priv *__lookup_fw_priv(const char *fw_name)
 213 {
 214         struct fw_priv *tmp;
 215         struct firmware_cache *fwc = &fw_cache;
 216
 217         list_for_each_entry(tmp, &fwc->head, list)
 218                 if (!strcmp(tmp->fw_name, fw_name))
 219                         return tmp;
 220         return NULL;
 221 }
 222
 223 /* Returns 1 for batching firmware requests with the same name */
 224 static int alloc_lookup_fw_priv(const char *fw_name,
 225                                 struct firmware_cache *fwc,
 226                                 struct fw_priv **fw_priv,
 227                                 void *dbuf,
 228                                 size_t size,
 229                                 size_t offset,
 230                                 u32 opt_flags)
 231 {
 232         struct fw_priv *tmp;
 233
 234         spin_lock(&fwc->lock);
 235         /*
 236          * Do not merge requests that are marked to be non-cached or
 237          * are performing partial reads.
 238          */
 239         if (!(opt_flags & (FW_OPT_NOCACHE | FW_OPT_PARTIAL))) {
 240                 tmp = __lookup_fw_priv(fw_name);
 241                 if (tmp) {
 242                         kref_get(&tmp->ref);
 243                         spin_unlock(&fwc->lock);
 244                         *fw_priv = tmp;
 245                         pr_debug("batched request - sharing the same struct fw_priv and lookup for multiple requests\n");
 246                         return 1;
 247                 }
 248         }
 249
 250         tmp = __allocate_fw_priv(fw_name, fwc, dbuf, size, offset, opt_flags);
 251         if (tmp) {
 252                 INIT_LIST_HEAD(&tmp->list);
 253                 if (!(opt_flags & FW_OPT_NOCACHE))
 254                         list_add(&tmp->list, &fwc->head);
 255         }
 256         spin_unlock(&fwc->lock);
 257
 258         *fw_priv = tmp;
 259
 260         return tmp ? 0 : -ENOMEM;
 261 }
 262
 263 static void __free_fw_priv(struct kref *ref)
 264         __releases(&fwc->lock)
 265 {
 266         struct fw_priv *fw_priv = to_fw_priv(ref);
 267         struct firmware_cache *fwc = fw_priv->fwc;
 268
 269         pr_debug("%s: fw-%s fw_priv=%p data=%p size=%u\n",
 270                  __func__, fw_priv->fw_name, fw_priv, fw_priv->data,
 271                  (unsigned int)fw_priv->size);
 272
 273         list_del(&fw_priv->list);
 274         spin_unlock(&fwc->lock);
 275
 276         if (fw_is_paged_buf(fw_priv))
 277                 fw_free_paged_buf(fw_priv);
 278         else if (!fw_priv->allocated_size)
 279                 vfree(fw_priv->data);
 280
 281         kfree_const(fw_priv->fw_name);
 282         kfree(fw_priv);
 283 }
 284
 285 static void free_fw_priv(struct fw_priv *fw_priv)
 286 {
 287         struct firmware_cache *fwc = fw_priv->fwc;
 288         spin_lock(&fwc->lock);
 289         if (!kref_put(&fw_priv->ref, __free_fw_priv))
 290                 spin_unlock(&fwc->lock);
 291 }
 292
 293 #ifdef CONFIG_FW_LOADER_PAGED_BUF
 294 bool fw_is_paged_buf(struct fw_priv *fw_priv)
 295 {
 296         return fw_priv->is_paged_buf;
 297 }
 298
 299 void fw_free_paged_buf(struct fw_priv *fw_priv)
 300 {
 301         int i;
 302
 303         if (!fw_priv->pages)
 304                 return;
 305
 306         vunmap(fw_priv->data);
 307
 308         for (i = 0; i < fw_priv->nr_pages; i++)
 309                 __free_page(fw_priv->pages[i]);
 310         kvfree(fw_priv->pages);
 311         fw_priv->pages = NULL;
 312         fw_priv->page_array_size = 0;
 313         fw_priv->nr_pages = 0;
 314 }
 315
 316 int fw_grow_paged_buf(struct fw_priv *fw_priv, int pages_needed)
 317 {
 318         /* If the array of pages is too small, grow it */
 319         if (fw_priv->page_array_size < pages_needed) {
 320                 int new_array_size = max(pages_needed,
 321                                          fw_priv->page_array_size * 2);
 322                 struct page **new_pages;
 323
 324                 new_pages = kvmalloc_array(new_array_size, sizeof(void *),
 325                                            GFP_KERNEL);
 326                 if (!new_pages)
 327                         return -ENOMEM;
 328                 memcpy(new_pages, fw_priv->pages,
 329                        fw_priv->page_array_size * sizeof(void *));
 330                 memset(&new_pages[fw_priv->page_array_size], 0, sizeof(void *) *
 331                        (new_array_size - fw_priv->page_array_size));
 332                 kvfree(fw_priv->pages);
 333                 fw_priv->pages = new_pages;
 334                 fw_priv->page_array_size = new_array_size;
 335         }
 336
 337         while (fw_priv->nr_pages < pages_needed) {
 338                 fw_priv->pages[fw_priv->nr_pages] =
 339                         alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
 340
 341                 if (!fw_priv->pages[fw_priv->nr_pages])
 342                         return -ENOMEM;
 343                 fw_priv->nr_pages++;
 344         }
 345
 346         return 0;
 347 }
 348
 349 int fw_map_paged_buf(struct fw_priv *fw_priv)
 350 {
 351         /* one pages buffer should be mapped/unmapped only once */
 352         if (!fw_priv->pages)
 353                 return 0;
 354
 355         vunmap(fw_priv->data);
 356         fw_priv->data = vmap(fw_priv->pages, fw_priv->nr_pages, 0,
 357                              PAGE_KERNEL_RO);
 358         if (!fw_priv->data)
 359                 return -ENOMEM;
 360
 361         return 0;
 362 }
 363 #endif
 364
 365 /*
 366  * XZ-compressed firmware support
 367  */
 368 #ifdef CONFIG_FW_LOADER_COMPRESS
 369 /* show an error and return the standard error code */
 370 static int fw_decompress_xz_error(struct device *dev, enum xz_ret xz_ret)
 371 {
 372         if (xz_ret != XZ_STREAM_END) {
 373                 dev_warn(dev, "xz decompression failed (xz_ret=%d)\n", xz_ret);
 374                 return xz_ret == XZ_MEM_ERROR ? -ENOMEM : -EINVAL;
 375         }
 376         return 0;
 377 }
 378
 379 /* single-shot decompression onto the pre-allocated buffer */
 380 static int fw_decompress_xz_single(struct device *dev, struct fw_priv *fw_priv,
 381                                    size_t in_size, const void *in_buffer)
 382 {
 383         struct xz_dec *xz_dec;
 384         struct xz_buf xz_buf;
 385         enum xz_ret xz_ret;
 386
 387         xz_dec = xz_dec_init(XZ_SINGLE, (u32)-1);
 388         if (!xz_dec)
 389                 return -ENOMEM;
 390
 391         xz_buf.in_size = in_size;
 392         xz_buf.in = in_buffer;
 393         xz_buf.in_pos = 0;
 394         xz_buf.out_size = fw_priv->allocated_size;
 395         xz_buf.out = fw_priv->data;
 396         xz_buf.out_pos = 0;
 397
 398         xz_ret = xz_dec_run(xz_dec, &xz_buf);
 399         xz_dec_end(xz_dec);
 400
 401         fw_priv->size = xz_buf.out_pos;
 402         return fw_decompress_xz_error(dev, xz_ret);
 403 }
 404
 405 /* decompression on paged buffer and map it */
 406 static int fw_decompress_xz_pages(struct device *dev, struct fw_priv *fw_priv,
 407                                   size_t in_size, const void *in_buffer)
 408 {
 409         struct xz_dec *xz_dec;
 410         struct xz_buf xz_buf;
 411         enum xz_ret xz_ret;
 412         struct page *page;
 413         int err = 0;
 414
 415         xz_dec = xz_dec_init(XZ_DYNALLOC, (u32)-1);
 416         if (!xz_dec)
 417                 return -ENOMEM;
 418
 419         xz_buf.in_size = in_size;
 420         xz_buf.in = in_buffer;
 421         xz_buf.in_pos = 0;
 422
 423         fw_priv->is_paged_buf = true;
 424         fw_priv->size = 0;
 425         do {
 426                 if (fw_grow_paged_buf(fw_priv, fw_priv->nr_pages + 1)) {
 427                         err = -ENOMEM;
 428                         goto out;
 429                 }
 430
 431                 /* decompress onto the new allocated page */
 432                 page = fw_priv->pages[fw_priv->nr_pages - 1];
 433                 xz_buf.out = kmap(page);
 434                 xz_buf.out_pos = 0;
 435                 xz_buf.out_size = PAGE_SIZE;
 436                 xz_ret = xz_dec_run(xz_dec, &xz_buf);
 437                 kunmap(page);
 438                 fw_priv->size += xz_buf.out_pos;
 439                 /* partial decompression means either end or error */
 440                 if (xz_buf.out_pos != PAGE_SIZE)
 441                         break;
 442         } while (xz_ret == XZ_OK);
 443
 444         err = fw_decompress_xz_error(dev, xz_ret);
 445         if (!err)
 446                 err = fw_map_paged_buf(fw_priv);
 447
 448  out:
 449         xz_dec_end(xz_dec);
 450         return err;
 451 }
 452
 453 static int fw_decompress_xz(struct device *dev, struct fw_priv *fw_priv,
 454                             size_t in_size, const void *in_buffer)
 455 {
 456         /* if the buffer is pre-allocated, we can perform in single-shot mode */
 457         if (fw_priv->data)
 458                 return fw_decompress_xz_single(dev, fw_priv, in_size, in_buffer);
 459         else
 460                 return fw_decompress_xz_pages(dev, fw_priv, in_size, in_buffer);
 461 }
 462 #endif /* CONFIG_FW_LOADER_COMPRESS */
 463
 464 /* direct firmware loading support */
 465 static char fw_path_para[256];
 466 static const char * const fw_path[] = {
 467         fw_path_para,
 468         "/lib/firmware/updates/" UTS_RELEASE,
 469         "/lib/firmware/updates",
 470         "/lib/firmware/" UTS_RELEASE,
 471         "/lib/firmware"
 472 };
 473
 474 /*
 475  * Typical usage is that passing 'firmware_class.path=$CUSTOMIZED_PATH'
 476  * from kernel command line because firmware_class is generally built in
 477  * kernel instead of module.
 478  */
 479 module_param_string(path, fw_path_para, sizeof(fw_path_para), 0644);
 480 MODULE_PARM_DESC(path, "customized firmware image search path with a higher priority than default path");
 481
 482 static int
 483 fw_get_filesystem_firmware(struct device *device, struct fw_priv *fw_priv,
 484                            const char *suffix,
 485                            int (*decompress)(struct device *dev,
 486                                              struct fw_priv *fw_priv,
 487                                              size_t in_size,
 488                                              const void *in_buffer))
 489 {
 490         size_t size;
 491         int i, len;
 492         int rc = -ENOENT;
 493         char *path;
 494         size_t msize = INT_MAX;
 495         void *buffer = NULL;
 496
 497         /* Already populated data member means we're loading into a buffer */
 498         if (!decompress && fw_priv->data) {
 499                 buffer = fw_priv->data;
 500                 msize = fw_priv->allocated_size;
 501         }
 502
 503         path = __getname();
 504         if (!path)
 505                 return -ENOMEM;
 506
 507         for (i = 0; i < ARRAY_SIZE(fw_path); i++) {
 508                 size_t file_size = 0;
 509                 size_t *file_size_ptr = NULL;
 510
 511                 /* skip the unset customized path */
 512                 if (!fw_path[i][0])
 513                         continue;
 514
 515                 len = snprintf(path, PATH_MAX, "%s/%s%s",
 516                                fw_path[i], fw_priv->fw_name, suffix);
 517                 if (len >= PATH_MAX) {
 518                         rc = -ENAMETOOLONG;
 519                         break;
 520                 }
 521
 522                 fw_priv->size = 0;
 523
 524                 /*
 525                  * The total file size is only examined when doing a partial
 526                  * read; the "full read" case needs to fail if the whole
 527                  * firmware was not completely loaded.
 528                  */
 529                 if ((fw_priv->opt_flags & FW_OPT_PARTIAL) && buffer)
 530                         file_size_ptr = &file_size;
 531
 532                 /* load firmware files from the mount namespace of init */
 533                 rc = kernel_read_file_from_path_initns(path, fw_priv->offset,
 534                                                        &buffer, msize,
 535                                                        file_size_ptr,
 536                                                        READING_FIRMWARE);
 537                 if (rc < 0) {
 538                         if (rc != -ENOENT)
 539                                 dev_warn(device, "loading %s failed with error %d\n",
 540                                          path, rc);
 541                         else
 542                                 dev_dbg(device, "loading %s failed for no such file or directory.\n",
 543                                          path);
 544                         continue;
 545                 }
 546                 size = rc;
 547                 rc = 0;
 548
 549                 dev_dbg(device, "Loading firmware from %s\n", path);
 550                 if (decompress) {
 551                         dev_dbg(device, "f/w decompressing %s\n",
 552                                 fw_priv->fw_name);
 553                         rc = decompress(device, fw_priv, size, buffer);
 554                         /* discard the superfluous original content */
 555                         vfree(buffer);
 556                         buffer = NULL;
 557                         if (rc) {
 558                                 fw_free_paged_buf(fw_priv);
 559                                 continue;
 560                         }
 561                 } else {
 562                         dev_dbg(device, "direct-loading %s\n",
 563                                 fw_priv->fw_name);
 564                         if (!fw_priv->data)
 565                                 fw_priv->data = buffer;
 566                         fw_priv->size = size;
 567                 }
 568                 fw_state_done(fw_priv);
 569                 break;
 570         }
 571         __putname(path);
 572
 573         return rc;
 574 }
 575
 576 /* firmware holds the ownership of pages */
 577 static void firmware_free_data(const struct firmware *fw)
 578 {
 579         /* Loaded directly? */
 580         if (!fw->priv) {
 581                 vfree(fw->data);
 582                 return;
 583         }
 584         free_fw_priv(fw->priv);
 585 }
 586
 587 /* store the pages buffer info firmware from buf */
 588 static void fw_set_page_data(struct fw_priv *fw_priv, struct firmware *fw)
 589 {
 590         fw->priv = fw_priv;
 591         fw->size = fw_priv->size;
 592         fw->data = fw_priv->data;
 593
 594         pr_debug("%s: fw-%s fw_priv=%p data=%p size=%u\n",
 595                  __func__, fw_priv->fw_name, fw_priv, fw_priv->data,
 596                  (unsigned int)fw_priv->size);
 597 }
 598
 599 #ifdef CONFIG_FW_CACHE
 600 static void fw_name_devm_release(struct device *dev, void *res)
 601 {
 602         struct fw_name_devm *fwn = res;
 603
 604         if (fwn->magic == (unsigned long)&fw_cache)
 605                 pr_debug("%s: fw_name-%s devm-%p released\n",
 606                                 __func__, fwn->name, res);
 607         kfree_const(fwn->name);
 608 }
 609
 610 static int fw_devm_match(struct device *dev, void *res,
 611                 void *match_data)
 612 {
 613         struct fw_name_devm *fwn = res;
 614
 615         return (fwn->magic == (unsigned long)&fw_cache) &&
 616                 !strcmp(fwn->name, match_data);
 617 }
 618
 619 static struct fw_name_devm *fw_find_devm_name(struct device *dev,
 620                 const char *name)
 621 {
 622         struct fw_name_devm *fwn;
 623
 624         fwn = devres_find(dev, fw_name_devm_release,
 625                           fw_devm_match, (void *)name);
 626         return fwn;
 627 }
 628
 629 static bool fw_cache_is_setup(struct device *dev, const char *name)
 630 {
 631         struct fw_name_devm *fwn;
 632
 633         fwn = fw_find_devm_name(dev, name);
 634         if (fwn)
 635                 return true;
 636
 637         return false;
 638 }
 639
 640 /* add firmware name into devres list */
 641 static int fw_add_devm_name(struct device *dev, const char *name)
 642 {
 643         struct fw_name_devm *fwn;
 644
 645         if (fw_cache_is_setup(dev, name))
 646                 return 0;
 647
 648         fwn = devres_alloc(fw_name_devm_release, sizeof(struct fw_name_devm),
 649                            GFP_KERNEL);
 650         if (!fwn)
 651                 return -ENOMEM;
 652         fwn->name = kstrdup_const(name, GFP_KERNEL);
 653         if (!fwn->name) {
 654                 devres_free(fwn);
 655                 return -ENOMEM;
 656         }
 657
 658         fwn->magic = (unsigned long)&fw_cache;
 659         devres_add(dev, fwn);
 660
 661         return 0;
 662 }
 663 #else
 664 static bool fw_cache_is_setup(struct device *dev, const char *name)
 665 {
 666         return false;
 667 }
 668
 669 static int fw_add_devm_name(struct device *dev, const char *name)
 670 {
 671         return 0;
 672 }
 673 #endif
 674
 675 int assign_fw(struct firmware *fw, struct device *device)
 676 {
 677         struct fw_priv *fw_priv = fw->priv;
 678         int ret;
 679
 680         mutex_lock(&fw_lock);
 681         if (!fw_priv->size || fw_state_is_aborted(fw_priv)) {
 682                 mutex_unlock(&fw_lock);
 683                 return -ENOENT;
 684         }
 685
 686         /*
 687          * add firmware name into devres list so that we can auto cache
 688          * and uncache firmware for device.
 689          *
 690          * device may has been deleted already, but the problem
 691          * should be fixed in devres or driver core.
 692          */
 693         /* don't cache firmware handled without uevent */
 694         if (device && (fw_priv->opt_flags & FW_OPT_UEVENT) &&
 695             !(fw_priv->opt_flags & FW_OPT_NOCACHE)) {
 696                 ret = fw_add_devm_name(device, fw_priv->fw_name);
 697                 if (ret) {
 698                         mutex_unlock(&fw_lock);
 699                         return ret;
 700                 }
 701         }
 702
 703         /*
 704          * After caching firmware image is started, let it piggyback
 705          * on request firmware.
 706          */
 707         if (!(fw_priv->opt_flags & FW_OPT_NOCACHE) &&
 708             fw_priv->fwc->state == FW_LOADER_START_CACHE) {
 709                 if (fw_cache_piggyback_on_request(fw_priv->fw_name))
 710                         kref_get(&fw_priv->ref);
 711         }
 712
 713         /* pass the pages buffer to driver at the last minute */
 714         fw_set_page_data(fw_priv, fw);
 715         mutex_unlock(&fw_lock);
 716         return 0;
 717 }
 718
 719 /* prepare firmware and firmware_buf structs;
 720  * return 0 if a firmware is already assigned, 1 if need to load one,
 721  * or a negative error code
 722  */
 723 static int
 724 _request_firmware_prepare(struct firmware **firmware_p, const char *name,
 725                           struct device *device, void *dbuf, size_t size,
 726                           size_t offset, u32 opt_flags)
 727 {
 728         struct firmware *firmware;
 729         struct fw_priv *fw_priv;
 730         int ret;
 731
 732         *firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
 733         if (!firmware) {
 734                 dev_err(device, "%s: kmalloc(struct firmware) failed\n",
 735                         __func__);
 736                 return -ENOMEM;
 737         }
 738
 739         if (fw_get_builtin_firmware(firmware, name, dbuf, size)) {
 740                 dev_dbg(device, "using built-in %s\n", name);
 741                 return 0; /* assigned */
 742         }
 743
 744         ret = alloc_lookup_fw_priv(name, &fw_cache, &fw_priv, dbuf, size,
 745                                    offset, opt_flags);
 746
 747         /*
 748          * bind with 'priv' now to avoid warning in failure path
 749          * of requesting firmware.
 750          */
 751         firmware->priv = fw_priv;
 752
 753         if (ret > 0) {
 754                 ret = fw_state_wait(fw_priv);
 755                 if (!ret) {
 756                         fw_set_page_data(fw_priv, firmware);
 757                         return 0; /* assigned */
 758                 }
 759         }
 760
 761         if (ret < 0)
 762                 return ret;
 763         return 1; /* need to load */
 764 }
 765
 766 /*
 767  * Batched requests need only one wake, we need to do this step last due to the
 768  * fallback mechanism. The buf is protected with kref_get(), and it won't be
 769  * released until the last user calls release_firmware().
 770  *
 771  * Failed batched requests are possible as well, in such cases we just share
 772  * the struct fw_priv and won't release it until all requests are woken
 773  * and have gone through this same path.
 774  */
 775 static void fw_abort_batch_reqs(struct firmware *fw)
 776 {
 777         struct fw_priv *fw_priv;
 778
 779         /* Loaded directly? */
 780         if (!fw || !fw->priv)
 781                 return;
 782
 783         fw_priv = fw->priv;
 784         if (!fw_state_is_aborted(fw_priv))
 785                 fw_state_aborted(fw_priv);
 786 }
 787
 788 /* called from request_firmware() and request_firmware_work_func() */
 789 static int
 790 _request_firmware(const struct firmware **firmware_p, const char *name,
 791                   struct device *device, void *buf, size_t size,
 792                   size_t offset, u32 opt_flags)
 793 {
 794         struct firmware *fw = NULL;
 795         bool nondirect = false;
 796         int ret;
 797
 798         if (!firmware_p)
 799                 return -EINVAL;
 800
 801         if (!name || name[0] == '\0') {
 802                 ret = -EINVAL;
 803                 goto out;
 804         }
 805
 806         ret = _request_firmware_prepare(&fw, name, device, buf, size,
 807                                         offset, opt_flags);
 808         if (ret <= 0) /* error or already assigned */
 809                 goto out;
 810
 811         ret = fw_get_filesystem_firmware(device, fw->priv, "", NULL);
 812
 813         /* Only full reads can support decompression, platform, and sysfs. */
 814         if (!(opt_flags & FW_OPT_PARTIAL))
 815                 nondirect = true;
 816
 817 #ifdef CONFIG_FW_LOADER_COMPRESS
 818         if (ret == -ENOENT && nondirect)
 819                 ret = fw_get_filesystem_firmware(device, fw->priv, ".xz",
 820                                                  fw_decompress_xz);
 821 #endif
 822         if (ret == -ENOENT && nondirect)
 823                 ret = firmware_fallback_platform(fw->priv);
 824
 825         if (ret) {
 826                 if (!(opt_flags & FW_OPT_NO_WARN))
 827                         dev_warn(device,
 828                                  "Direct firmware load for %s failed with error %d\n",
 829                                  name, ret);
 830                 if (nondirect)
 831                         ret = firmware_fallback_sysfs(fw, name, device,
 832                                                       opt_flags, ret);
 833         } else
 834                 ret = assign_fw(fw, device);
 835
 836  out:
 837         if (ret < 0) {
 838                 fw_abort_batch_reqs(fw);
 839                 release_firmware(fw);
 840                 fw = NULL;
 841         }
 842
 843         *firmware_p = fw;
 844         return ret;
 845 }
 846
 847 /**
 848  * request_firmware() - send firmware request and wait for it
 849  * @firmware_p: pointer to firmware image
 850  * @name: name of firmware file
 851  * @device: device for which firmware is being loaded
 852  *
 853  *      @firmware_p will be used to return a firmware image by the name
 854  *      of @name for device @device.
 855  *
 856  *      Should be called from user context where sleeping is allowed.
 857  *
 858  *      @name will be used as $FIRMWARE in the uevent environment and
 859  *      should be distinctive enough not to be confused with any other
 860  *      firmware image for this or any other device.
 861  *
 862  *      Caller must hold the reference count of @device.
 863  *
 864  *      The function can be called safely inside device's suspend and
 865  *      resume callback.
 866  **/
 867 int
 868 request_firmware(const struct firmware **firmware_p, const char *name,
 869                  struct device *device)
 870 {
 871         int ret;
 872
 873         /* Need to pin this module until return */
 874         __module_get(THIS_MODULE);
 875         ret = _request_firmware(firmware_p, name, device, NULL, 0, 0,
 876                                 FW_OPT_UEVENT);
 877         module_put(THIS_MODULE);
 878         return ret;
 879 }
 880 EXPORT_SYMBOL(request_firmware);
 881
 882 /**
 883  * firmware_request_nowarn() - request for an optional fw module
 884  * @firmware: pointer to firmware image
 885  * @name: name of firmware file
 886  * @device: device for which firmware is being loaded
 887  *
 888  * This function is similar in behaviour to request_firmware(), except it
 889  * doesn't produce warning messages when the file is not found. The sysfs
 890  * fallback mechanism is enabled if direct filesystem lookup fails. However,
 891  * failures to find the firmware file with it are still suppressed. It is
 892  * therefore up to the driver to check for the return value of this call and to
 893  * decide when to inform the users of errors.
 894  **/
 895 int firmware_request_nowarn(const struct firmware **firmware, const char *name,
 896                             struct device *device)
 897 {
 898         int ret;
 899
 900         /* Need to pin this module until return */
 901         __module_get(THIS_MODULE);
 902         ret = _request_firmware(firmware, name, device, NULL, 0, 0,
 903                                 FW_OPT_UEVENT | FW_OPT_NO_WARN);
 904         module_put(THIS_MODULE);
 905         return ret;
 906 }
 907 EXPORT_SYMBOL_GPL(firmware_request_nowarn);
 908
 909 /**
 910  * request_firmware_direct() - load firmware directly without usermode helper
 911  * @firmware_p: pointer to firmware image
 912  * @name: name of firmware file
 913  * @device: device for which firmware is being loaded
 914  *
 915  * This function works pretty much like request_firmware(), but this doesn't
 916  * fall back to usermode helper even if the firmware couldn't be loaded
 917  * directly from fs.  Hence it's useful for loading optional firmwares, which
 918  * aren't always present, without extra long timeouts of udev.
 919  **/
 920 int request_firmware_direct(const struct firmware **firmware_p,
 921                             const char *name, struct device *device)
 922 {
 923         int ret;
 924
 925         __module_get(THIS_MODULE);
 926         ret = _request_firmware(firmware_p, name, device, NULL, 0, 0,
 927                                 FW_OPT_UEVENT | FW_OPT_NO_WARN |
 928                                 FW_OPT_NOFALLBACK_SYSFS);
 929         module_put(THIS_MODULE);
 930         return ret;
 931 }
 932 EXPORT_SYMBOL_GPL(request_firmware_direct);
 933
 934 /**
 935  * firmware_request_platform() - request firmware with platform-fw fallback
 936  * @firmware: pointer to firmware image
 937  * @name: name of firmware file
 938  * @device: device for which firmware is being loaded
 939  *
 940  * This function is similar in behaviour to request_firmware, except that if
 941  * direct filesystem lookup fails, it will fallback to looking for a copy of the
 942  * requested firmware embedded in the platform's main (e.g. UEFI) firmware.
 943  **/
 944 int firmware_request_platform(const struct firmware **firmware,
 945                               const char *name, struct device *device)
 946 {
 947         int ret;
 948
 949         /* Need to pin this module until return */
 950         __module_get(THIS_MODULE);
 951         ret = _request_firmware(firmware, name, device, NULL, 0, 0,
 952                                 FW_OPT_UEVENT | FW_OPT_FALLBACK_PLATFORM);
 953         module_put(THIS_MODULE);
 954         return ret;
 955 }
 956 EXPORT_SYMBOL_GPL(firmware_request_platform);
 957
 958 /**
 959  * firmware_request_cache() - cache firmware for suspend so resume can use it
 960  * @name: name of firmware file
 961  * @device: device for which firmware should be cached for
 962  *
 963  * There are some devices with an optimization that enables the device to not
 964  * require loading firmware on system reboot. This optimization may still
 965  * require the firmware present on resume from suspend. This routine can be
 966  * used to ensure the firmware is present on resume from suspend in these
 967  * situations. This helper is not compatible with drivers which use
 968  * request_firmware_into_buf() or request_firmware_nowait() with no uevent set.
 969  **/
 970 int firmware_request_cache(struct device *device, const char *name)
 971 {
 972         int ret;
 973
 974         mutex_lock(&fw_lock);
 975         ret = fw_add_devm_name(device, name);
 976         mutex_unlock(&fw_lock);
 977
 978         return ret;
 979 }
 980 EXPORT_SYMBOL_GPL(firmware_request_cache);
 981
 982 /**
 983  * request_firmware_into_buf() - load firmware into a previously allocated buffer
 984  * @firmware_p: pointer to firmware image
 985  * @name: name of firmware file
 986  * @device: device for which firmware is being loaded and DMA region allocated
 987  * @buf: address of buffer to load firmware into
 988  * @size: size of buffer
 989  *
 990  * This function works pretty much like request_firmware(), but it doesn't
 991  * allocate a buffer to hold the firmware data. Instead, the firmware
 992  * is loaded directly into the buffer pointed to by @buf and the @firmware_p
 993  * data member is pointed at @buf.
 994  *
 995  * This function doesn't cache firmware either.
 996  */
 997 int
 998 request_firmware_into_buf(const struct firmware **firmware_p, const char *name,
 999                           struct device *device, void *buf, size_t size)
1000 {
1001         int ret;
1002
1003         if (fw_cache_is_setup(device, name))
1004                 return -EOPNOTSUPP;
1005
1006         __module_get(THIS_MODULE);
1007         ret = _request_firmware(firmware_p, name, device, buf, size, 0,
1008                                 FW_OPT_UEVENT | FW_OPT_NOCACHE);
1009         module_put(THIS_MODULE);
1010         return ret;
1011 }
1012 EXPORT_SYMBOL(request_firmware_into_buf);
1013
1014 /**
1015  * request_partial_firmware_into_buf() - load partial firmware into a previously allocated buffer
1016  * @firmware_p: pointer to firmware image
1017  * @name: name of firmware file
1018  * @device: device for which firmware is being loaded and DMA region allocated
1019  * @buf: address of buffer to load firmware into
1020  * @size: size of buffer
1021  * @offset: offset into file to read
1022  *
1023  * This function works pretty much like request_firmware_into_buf except
1024  * it allows a partial read of the file.
1025  */
1026 int
1027 request_partial_firmware_into_buf(const struct firmware **firmware_p,
1028                                   const char *name, struct device *device,
1029                                   void *buf, size_t size, size_t offset)
1030 {
1031         int ret;
1032
1033         if (fw_cache_is_setup(device, name))
1034                 return -EOPNOTSUPP;
1035
1036         __module_get(THIS_MODULE);
1037         ret = _request_firmware(firmware_p, name, device, buf, size, offset,
1038                                 FW_OPT_UEVENT | FW_OPT_NOCACHE |
1039                                 FW_OPT_PARTIAL);
1040         module_put(THIS_MODULE);
1041         return ret;
1042 }
1043 EXPORT_SYMBOL(request_partial_firmware_into_buf);
1044
1045 /**
1046  * release_firmware() - release the resource associated with a firmware image
1047  * @fw: firmware resource to release
1048  **/
1049 void release_firmware(const struct firmware *fw)
1050 {
1051         if (fw) {
1052                 if (!fw_is_builtin_firmware(fw))
1053                         firmware_free_data(fw);
1054                 kfree(fw);
1055         }
1056 }
1057 EXPORT_SYMBOL(release_firmware);
1058
1059 /* Async support */
1060 struct firmware_work {
1061         struct work_struct work;
1062         struct module *module;
1063         const char *name;
1064         struct device *device;
1065         void *context;
1066         void (*cont)(const struct firmware *fw, void *context);
1067         u32 opt_flags;
1068 };
1069
1070 static void request_firmware_work_func(struct work_struct *work)
1071 {
1072         struct firmware_work *fw_work;
1073         const struct firmware *fw;
1074
1075         fw_work = container_of(work, struct firmware_work, work);
1076
1077         _request_firmware(&fw, fw_work->name, fw_work->device, NULL, 0, 0,
1078                           fw_work->opt_flags);
1079         fw_work->cont(fw, fw_work->context);
1080         put_device(fw_work->device); /* taken in request_firmware_nowait() */
1081
1082         module_put(fw_work->module);
1083         kfree_const(fw_work->name);
1084         kfree(fw_work);
1085 }
1086
1087 /**
1088  * request_firmware_nowait() - asynchronous version of request_firmware
1089  * @module: module requesting the firmware
1090  * @uevent: sends uevent to copy the firmware image if this flag
1091  *      is non-zero else the firmware copy must be done manually.
1092  * @name: name of firmware file
1093  * @device: device for which firmware is being loaded
1094  * @gfp: allocation flags
1095  * @context: will be passed over to @cont, and
1096  *      @fw may be %NULL if firmware request fails.
1097  * @cont: function will be called asynchronously when the firmware
1098  *      request is over.
1099  *
1100  *      Caller must hold the reference count of @device.
1101  *
1102  *      Asynchronous variant of request_firmware() for user contexts:
1103  *              - sleep for as small periods as possible since it may
1104  *                increase kernel boot time of built-in device drivers
1105  *                requesting firmware in their ->probe() methods, if
1106  *                @gfp is GFP_KERNEL.
1107  *
1108  *              - can't sleep at all if @gfp is GFP_ATOMIC.
1109  **/
1110 int
1111 request_firmware_nowait(
1112         struct module *module, bool uevent,
1113         const char *name, struct device *device, gfp_t gfp, void *context,
1114         void (*cont)(const struct firmware *fw, void *context))
1115 {
1116         struct firmware_work *fw_work;
1117
1118         fw_work = kzalloc(sizeof(struct firmware_work), gfp);
1119         if (!fw_work)
1120                 return -ENOMEM;
1121
1122         fw_work->module = module;
1123         fw_work->name = kstrdup_const(name, gfp);
1124         if (!fw_work->name) {
1125                 kfree(fw_work);
1126                 return -ENOMEM;
1127         }
1128         fw_work->device = device;
1129         fw_work->context = context;
1130         fw_work->cont = cont;
1131         fw_work->opt_flags = FW_OPT_NOWAIT |
1132                 (uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER);
1133
1134         if (!uevent && fw_cache_is_setup(device, name)) {
1135                 kfree_const(fw_work->name);
1136                 kfree(fw_work);
1137                 return -EOPNOTSUPP;
1138         }
1139
1140         if (!try_module_get(module)) {
1141                 kfree_const(fw_work->name);
1142                 kfree(fw_work);
1143                 return -EFAULT;
1144         }
1145
1146         get_device(fw_work->device);
1147         INIT_WORK(&fw_work->work, request_firmware_work_func);
1148         schedule_work(&fw_work->work);
1149         return 0;
1150 }
1151 EXPORT_SYMBOL(request_firmware_nowait);
1152
1153 #ifdef CONFIG_FW_CACHE
1154 static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
1155
1156 /**
1157  * cache_firmware() - cache one firmware image in kernel memory space
1158  * @fw_name: the firmware image name
1159  *
1160  * Cache firmware in kernel memory so that drivers can use it when
1161  * system isn't ready for them to request firmware image from userspace.
1162  * Once it returns successfully, driver can use request_firmware or its
1163  * nowait version to get the cached firmware without any interacting
1164  * with userspace
1165  *
1166  * Return 0 if the firmware image has been cached successfully
1167  * Return !0 otherwise
1168  *
1169  */
1170 static int cache_firmware(const char *fw_name)
1171 {
1172         int ret;
1173         const struct firmware *fw;
1174
1175         pr_debug("%s: %s\n", __func__, fw_name);
1176
1177         ret = request_firmware(&fw, fw_name, NULL);
1178         if (!ret)
1179                 kfree(fw);
1180
1181         pr_debug("%s: %s ret=%d\n", __func__, fw_name, ret);
1182
1183         return ret;
1184 }
1185
1186 static struct fw_priv *lookup_fw_priv(const char *fw_name)
1187 {
1188         struct fw_priv *tmp;
1189         struct firmware_cache *fwc = &fw_cache;
1190
1191         spin_lock(&fwc->lock);
1192         tmp = __lookup_fw_priv(fw_name);
1193         spin_unlock(&fwc->lock);
1194
1195         return tmp;
1196 }
1197
1198 /**
1199  * uncache_firmware() - remove one cached firmware image
1200  * @fw_name: the firmware image name
1201  *
1202  * Uncache one firmware image which has been cached successfully
1203  * before.
1204  *
1205  * Return 0 if the firmware cache has been removed successfully
1206  * Return !0 otherwise
1207  *
1208  */
1209 static int uncache_firmware(const char *fw_name)
1210 {
1211         struct fw_priv *fw_priv;
1212         struct firmware fw;
1213
1214         pr_debug("%s: %s\n", __func__, fw_name);
1215
1216         if (fw_get_builtin_firmware(&fw, fw_name, NULL, 0))
1217                 return 0;
1218
1219         fw_priv = lookup_fw_priv(fw_name);
1220         if (fw_priv) {
1221                 free_fw_priv(fw_priv);
1222                 return 0;
1223         }
1224
1225         return -EINVAL;
1226 }
1227
1228 static struct fw_cache_entry *alloc_fw_cache_entry(const char *name)
1229 {
1230         struct fw_cache_entry *fce;
1231
1232         fce = kzalloc(sizeof(*fce), GFP_ATOMIC);
1233         if (!fce)
1234                 goto exit;
1235
1236         fce->name = kstrdup_const(name, GFP_ATOMIC);
1237         if (!fce->name) {
1238                 kfree(fce);
1239                 fce = NULL;
1240                 goto exit;
1241         }
1242 exit:
1243         return fce;
1244 }
1245
1246 static int __fw_entry_found(const char *name)
1247 {
1248         struct firmware_cache *fwc = &fw_cache;
1249         struct fw_cache_entry *fce;
1250
1251         list_for_each_entry(fce, &fwc->fw_names, list) {
1252                 if (!strcmp(fce->name, name))
1253                         return 1;
1254         }
1255         return 0;
1256 }
1257
1258 static int fw_cache_piggyback_on_request(const char *name)
1259 {
1260         struct firmware_cache *fwc = &fw_cache;
1261         struct fw_cache_entry *fce;
1262         int ret = 0;
1263
1264         spin_lock(&fwc->name_lock);
1265         if (__fw_entry_found(name))
1266                 goto found;
1267
1268         fce = alloc_fw_cache_entry(name);
1269         if (fce) {
1270                 ret = 1;
1271                 list_add(&fce->list, &fwc->fw_names);
1272                 pr_debug("%s: fw: %s\n", __func__, name);
1273         }
1274 found:
1275         spin_unlock(&fwc->name_lock);
1276         return ret;
1277 }
1278
1279 static void free_fw_cache_entry(struct fw_cache_entry *fce)
1280 {
1281         kfree_const(fce->name);
1282         kfree(fce);
1283 }
1284
1285 static void __async_dev_cache_fw_image(void *fw_entry,
1286                                        async_cookie_t cookie)
1287 {
1288         struct fw_cache_entry *fce = fw_entry;
1289         struct firmware_cache *fwc = &fw_cache;
1290         int ret;
1291
1292         ret = cache_firmware(fce->name);
1293         if (ret) {
1294                 spin_lock(&fwc->name_lock);
1295                 list_del(&fce->list);
1296                 spin_unlock(&fwc->name_lock);
1297
1298                 free_fw_cache_entry(fce);
1299         }
1300 }
1301
1302 /* called with dev->devres_lock held */
1303 static void dev_create_fw_entry(struct device *dev, void *res,
1304                                 void *data)
1305 {
1306         struct fw_name_devm *fwn = res;
1307         const char *fw_name = fwn->name;
1308         struct list_head *head = data;
1309         struct fw_cache_entry *fce;
1310
1311         fce = alloc_fw_cache_entry(fw_name);
1312         if (fce)
1313                 list_add(&fce->list, head);
1314 }
1315
1316 static int devm_name_match(struct device *dev, void *res,
1317                            void *match_data)
1318 {
1319         struct fw_name_devm *fwn = res;
1320         return (fwn->magic == (unsigned long)match_data);
1321 }
1322
1323 static void dev_cache_fw_image(struct device *dev, void *data)
1324 {
1325         LIST_HEAD(todo);
1326         struct fw_cache_entry *fce;
1327         struct fw_cache_entry *fce_next;
1328         struct firmware_cache *fwc = &fw_cache;
1329
1330         devres_for_each_res(dev, fw_name_devm_release,
1331                             devm_name_match, &fw_cache,
1332                             dev_create_fw_entry, &todo);
1333
1334         list_for_each_entry_safe(fce, fce_next, &todo, list) {
1335                 list_del(&fce->list);
1336
1337                 spin_lock(&fwc->name_lock);
1338                 /* only one cache entry for one firmware */
1339                 if (!__fw_entry_found(fce->name)) {
1340                         list_add(&fce->list, &fwc->fw_names);
1341                 } else {
1342                         free_fw_cache_entry(fce);
1343                         fce = NULL;
1344                 }
1345                 spin_unlock(&fwc->name_lock);
1346
1347                 if (fce)
1348                         async_schedule_domain(__async_dev_cache_fw_image,
1349                                               (void *)fce,
1350                                               &fw_cache_domain);
1351         }
1352 }
1353
1354 static void __device_uncache_fw_images(void)
1355 {
1356         struct firmware_cache *fwc = &fw_cache;
1357         struct fw_cache_entry *fce;
1358
1359         spin_lock(&fwc->name_lock);
1360         while (!list_empty(&fwc->fw_names)) {
1361                 fce = list_entry(fwc->fw_names.next,
1362                                 struct fw_cache_entry, list);
1363                 list_del(&fce->list);
1364                 spin_unlock(&fwc->name_lock);
1365
1366                 uncache_firmware(fce->name);
1367                 free_fw_cache_entry(fce);
1368
1369                 spin_lock(&fwc->name_lock);
1370         }
1371         spin_unlock(&fwc->name_lock);
1372 }
1373
1374 /**
1375  * device_cache_fw_images() - cache devices' firmware
1376  *
1377  * If one device called request_firmware or its nowait version
1378  * successfully before, the firmware names are recored into the
1379  * device's devres link list, so device_cache_fw_images can call
1380  * cache_firmware() to cache these firmwares for the device,
1381  * then the device driver can load its firmwares easily at
1382  * time when system is not ready to complete loading firmware.
1383  */
1384 static void device_cache_fw_images(void)
1385 {
1386         struct firmware_cache *fwc = &fw_cache;
1387         DEFINE_WAIT(wait);
1388
1389         pr_debug("%s\n", __func__);
1390
1391         /* cancel uncache work */
1392         cancel_delayed_work_sync(&fwc->work);
1393
1394         fw_fallback_set_cache_timeout();
1395
1396         mutex_lock(&fw_lock);
1397         fwc->state = FW_LOADER_START_CACHE;
1398         dpm_for_each_dev(NULL, dev_cache_fw_image);
1399         mutex_unlock(&fw_lock);
1400
1401         /* wait for completion of caching firmware for all devices */
1402         async_synchronize_full_domain(&fw_cache_domain);
1403
1404         fw_fallback_set_default_timeout();
1405 }
1406
1407 /**
1408  * device_uncache_fw_images() - uncache devices' firmware
1409  *
1410  * uncache all firmwares which have been cached successfully
1411  * by device_uncache_fw_images earlier
1412  */
1413 static void device_uncache_fw_images(void)
1414 {
1415         pr_debug("%s\n", __func__);
1416         __device_uncache_fw_images();
1417 }
1418
1419 static void device_uncache_fw_images_work(struct work_struct *work)
1420 {
1421         device_uncache_fw_images();
1422 }
1423
1424 /**
1425  * device_uncache_fw_images_delay() - uncache devices firmwares
1426  * @delay: number of milliseconds to delay uncache device firmwares
1427  *
1428  * uncache all devices's firmwares which has been cached successfully
1429  * by device_cache_fw_images after @delay milliseconds.
1430  */
1431 static void device_uncache_fw_images_delay(unsigned long delay)
1432 {
1433         queue_delayed_work(system_power_efficient_wq, &fw_cache.work,
1434                            msecs_to_jiffies(delay));
1435 }
1436
1437 static int fw_pm_notify(struct notifier_block *notify_block,
1438                         unsigned long mode, void *unused)
1439 {
1440         switch (mode) {
1441         case PM_HIBERNATION_PREPARE:
1442         case PM_SUSPEND_PREPARE:
1443         case PM_RESTORE_PREPARE:
1444                 /*
1445                  * kill pending fallback requests with a custom fallback
1446                  * to avoid stalling suspend.
1447                  */
1448                 kill_pending_fw_fallback_reqs(true);
1449                 device_cache_fw_images();
1450                 break;
1451
1452         case PM_POST_SUSPEND:
1453         case PM_POST_HIBERNATION:
1454         case PM_POST_RESTORE:
1455                 /*
1456                  * In case that system sleep failed and syscore_suspend is
1457                  * not called.
1458                  */
1459                 mutex_lock(&fw_lock);
1460                 fw_cache.state = FW_LOADER_NO_CACHE;
1461                 mutex_unlock(&fw_lock);
1462
1463                 device_uncache_fw_images_delay(10 * MSEC_PER_SEC);
1464                 break;
1465         }
1466
1467         return 0;
1468 }
1469
1470 /* stop caching firmware once syscore_suspend is reached */
1471 static int fw_suspend(void)
1472 {
1473         fw_cache.state = FW_LOADER_NO_CACHE;
1474         return 0;
1475 }
1476
1477 static struct syscore_ops fw_syscore_ops = {
1478         .suspend = fw_suspend,
1479 };
1480
1481 static int __init register_fw_pm_ops(void)
1482 {
1483         int ret;
1484
1485         spin_lock_init(&fw_cache.name_lock);
1486         INIT_LIST_HEAD(&fw_cache.fw_names);
1487
1488         INIT_DELAYED_WORK(&fw_cache.work,
1489                           device_uncache_fw_images_work);
1490
1491         fw_cache.pm_notify.notifier_call = fw_pm_notify;
1492         ret = register_pm_notifier(&fw_cache.pm_notify);
1493         if (ret)
1494                 return ret;
1495
1496         register_syscore_ops(&fw_syscore_ops);
1497
1498         return ret;
1499 }
1500
1501 static inline void unregister_fw_pm_ops(void)
1502 {
1503         unregister_syscore_ops(&fw_syscore_ops);
1504         unregister_pm_notifier(&fw_cache.pm_notify);
1505 }
1506 #else
1507 static int fw_cache_piggyback_on_request(const char *name)
1508 {
1509         return 0;
1510 }
1511 static inline int register_fw_pm_ops(void)
1512 {
1513         return 0;
1514 }
1515 static inline void unregister_fw_pm_ops(void)
1516 {
1517 }
1518 #endif
1519
1520 static void __init fw_cache_init(void)
1521 {
1522         spin_lock_init(&fw_cache.lock);
1523         INIT_LIST_HEAD(&fw_cache.head);
1524         fw_cache.state = FW_LOADER_NO_CACHE;
1525 }
1526
1527 static int fw_shutdown_notify(struct notifier_block *unused1,
1528                               unsigned long unused2, void *unused3)
1529 {
1530         /*
1531          * Kill all pending fallback requests to avoid both stalling shutdown,
1532          * and avoid a deadlock with the usermode_lock.
1533          */
1534         kill_pending_fw_fallback_reqs(false);
1535
1536         return NOTIFY_DONE;
1537 }
1538
1539 static struct notifier_block fw_shutdown_nb = {
1540         .notifier_call = fw_shutdown_notify,
1541 };
1542
1543 static int __init firmware_class_init(void)
1544 {
1545         int ret;
1546
1547         /* No need to unfold these on exit */
1548         fw_cache_init();
1549
1550         ret = register_fw_pm_ops();
1551         if (ret)
1552                 return ret;
1553
1554         ret = register_reboot_notifier(&fw_shutdown_nb);
1555         if (ret)
1556                 goto out;
1557
1558         return register_sysfs_loader();
1559
1560 out:
1561         unregister_fw_pm_ops();
1562         return ret;
1563 }
1564
1565 static void __exit firmware_class_exit(void)
1566 {
1567         unregister_fw_pm_ops();
1568         unregister_reboot_notifier(&fw_shutdown_nb);
1569         unregister_sysfs_loader();
1570 }
1571
1572 fs_initcall(firmware_class_init);
1573 module_exit(firmware_class_exit);