drivers/base/firmware_class.c

   1 /*
   2  * firmware_class.c - Multi purpose firmware loading support
   3  *
   4  * Copyright (c) 2003 Manuel Estrada Sainz
   5  *
   6  * Please see Documentation/firmware_class/ for more information.
   7  *
   8  */
   9
  10 #include <linux/capability.h>
  11 #include <linux/device.h>
  12 #include <linux/module.h>
  13 #include <linux/init.h>
  14 #include <linux/timer.h>
  15 #include <linux/vmalloc.h>
  16 #include <linux/interrupt.h>
  17 #include <linux/bitops.h>
  18 #include <linux/mutex.h>
  19 #include <linux/workqueue.h>
  20 #include <linux/highmem.h>
  21 #include <linux/firmware.h>
  22 #include <linux/slab.h>
  23 #include <linux/sched.h>
  24 #include <linux/file.h>
  25 #include <linux/list.h>
  26 #include <linux/async.h>
  27 #include <linux/pm.h>
  28 #include <linux/suspend.h>
  29 #include <linux/syscore_ops.h>
  30 #include <linux/reboot.h>
  31 #include <linux/security.h>
  32
  33 #include <generated/utsrelease.h>
  34
  35 #include "base.h"
  36
  37 MODULE_AUTHOR("Manuel Estrada Sainz");
  38 MODULE_DESCRIPTION("Multi purpose firmware loading support");
  39 MODULE_LICENSE("GPL");
  40
  41 /* Builtin firmware support */
  42
  43 #ifdef CONFIG_FW_LOADER
  44
  45 extern struct builtin_fw __start_builtin_fw[];
  46 extern struct builtin_fw __end_builtin_fw[];
  47
  48 static bool fw_get_builtin_firmware(struct firmware *fw, const char *name)
  49 {
  50         struct builtin_fw *b_fw;
  51
  52         for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++) {
  53                 if (strcmp(name, b_fw->name) == 0) {
  54                         fw->size = b_fw->size;
  55                         fw->data = b_fw->data;
  56                         return true;
  57                 }
  58         }
  59
  60         return false;
  61 }
  62
  63 static bool fw_is_builtin_firmware(const struct firmware *fw)
  64 {
  65         struct builtin_fw *b_fw;
  66
  67         for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++)
  68                 if (fw->data == b_fw->data)
  69                         return true;
  70
  71         return false;
  72 }
  73
  74 #else /* Module case - no builtin firmware support */
  75
  76 static inline bool fw_get_builtin_firmware(struct firmware *fw, const char *name)
  77 {
  78         return false;
  79 }
  80
  81 static inline bool fw_is_builtin_firmware(const struct firmware *fw)
  82 {
  83         return false;
  84 }
  85 #endif
  86
  87 enum {
  88         FW_STATUS_LOADING,
  89         FW_STATUS_DONE,
  90         FW_STATUS_ABORT,
  91 };
  92
  93 static int loading_timeout = 60;        /* In seconds */
  94
  95 static inline long firmware_loading_timeout(void)
  96 {
  97         return loading_timeout > 0 ? loading_timeout * HZ : MAX_JIFFY_OFFSET;
  98 }
  99
 100 /* firmware behavior options */
 101 #define FW_OPT_UEVENT   (1U << 0)
 102 #define FW_OPT_NOWAIT   (1U << 1)
 103 #ifdef CONFIG_FW_LOADER_USER_HELPER
 104 #define FW_OPT_USERHELPER       (1U << 2)
 105 #else
 106 #define FW_OPT_USERHELPER       0
 107 #endif
 108 #ifdef CONFIG_FW_LOADER_USER_HELPER_FALLBACK
 109 #define FW_OPT_FALLBACK         FW_OPT_USERHELPER
 110 #else
 111 #define FW_OPT_FALLBACK         0
 112 #endif
 113 #define FW_OPT_NO_WARN  (1U << 3)
 114
 115 struct firmware_cache {
 116         /* firmware_buf instance will be added into the below list */
 117         spinlock_t lock;
 118         struct list_head head;
 119         int state;
 120
 121 #ifdef CONFIG_PM_SLEEP
 122         /*
 123          * Names of firmware images which have been cached successfully
 124          * will be added into the below list so that device uncache
 125          * helper can trace which firmware images have been cached
 126          * before.
 127          */
 128         spinlock_t name_lock;
 129         struct list_head fw_names;
 130
 131         struct delayed_work work;
 132
 133         struct notifier_block   pm_notify;
 134 #endif
 135 };
 136
 137 struct firmware_buf {
 138         struct kref ref;
 139         struct list_head list;
 140         struct completion completion;
 141         struct firmware_cache *fwc;
 142         unsigned long status;
 143         void *data;
 144         size_t size;
 145 #ifdef CONFIG_FW_LOADER_USER_HELPER
 146         bool is_paged_buf;
 147         bool need_uevent;
 148         struct page **pages;
 149         int nr_pages;
 150         int page_array_size;
 151         struct list_head pending_list;
 152 #endif
 153         char fw_id[];
 154 };
 155
 156 struct fw_cache_entry {
 157         struct list_head list;
 158         char name[];
 159 };
 160
 161 struct fw_name_devm {
 162         unsigned long magic;
 163         char name[];
 164 };
 165
 166 #define to_fwbuf(d) container_of(d, struct firmware_buf, ref)
 167
 168 #define FW_LOADER_NO_CACHE      0
 169 #define FW_LOADER_START_CACHE   1
 170
 171 static int fw_cache_piggyback_on_request(const char *name);
 172
 173 /* fw_lock could be moved to 'struct firmware_priv' but since it is just
 174  * guarding for corner cases a global lock should be OK */
 175 static DEFINE_MUTEX(fw_lock);
 176
 177 static struct firmware_cache fw_cache;
 178
 179 static struct firmware_buf *__allocate_fw_buf(const char *fw_name,
 180                                               struct firmware_cache *fwc)
 181 {
 182         struct firmware_buf *buf;
 183
 184         buf = kzalloc(sizeof(*buf) + strlen(fw_name) + 1 , GFP_ATOMIC);
 185
 186         if (!buf)
 187                 return buf;
 188
 189         kref_init(&buf->ref);
 190         strcpy(buf->fw_id, fw_name);
 191         buf->fwc = fwc;
 192         init_completion(&buf->completion);
 193 #ifdef CONFIG_FW_LOADER_USER_HELPER
 194         INIT_LIST_HEAD(&buf->pending_list);
 195 #endif
 196
 197         pr_debug("%s: fw-%s buf=%p\n", __func__, fw_name, buf);
 198
 199         return buf;
 200 }
 201
 202 static struct firmware_buf *__fw_lookup_buf(const char *fw_name)
 203 {
 204         struct firmware_buf *tmp;
 205         struct firmware_cache *fwc = &fw_cache;
 206
 207         list_for_each_entry(tmp, &fwc->head, list)
 208                 if (!strcmp(tmp->fw_id, fw_name))
 209                         return tmp;
 210         return NULL;
 211 }
 212
 213 static int fw_lookup_and_allocate_buf(const char *fw_name,
 214                                       struct firmware_cache *fwc,
 215                                       struct firmware_buf **buf)
 216 {
 217         struct firmware_buf *tmp;
 218
 219         spin_lock(&fwc->lock);
 220         tmp = __fw_lookup_buf(fw_name);
 221         if (tmp) {
 222                 kref_get(&tmp->ref);
 223                 spin_unlock(&fwc->lock);
 224                 *buf = tmp;
 225                 return 1;
 226         }
 227         tmp = __allocate_fw_buf(fw_name, fwc);
 228         if (tmp)
 229                 list_add(&tmp->list, &fwc->head);
 230         spin_unlock(&fwc->lock);
 231
 232         *buf = tmp;
 233
 234         return tmp ? 0 : -ENOMEM;
 235 }
 236
 237 static void __fw_free_buf(struct kref *ref)
 238         __releases(&fwc->lock)
 239 {
 240         struct firmware_buf *buf = to_fwbuf(ref);
 241         struct firmware_cache *fwc = buf->fwc;
 242
 243         pr_debug("%s: fw-%s buf=%p data=%p size=%u\n",
 244                  __func__, buf->fw_id, buf, buf->data,
 245                  (unsigned int)buf->size);
 246
 247         list_del(&buf->list);
 248         spin_unlock(&fwc->lock);
 249
 250 #ifdef CONFIG_FW_LOADER_USER_HELPER
 251         if (buf->is_paged_buf) {
 252                 int i;
 253                 vunmap(buf->data);
 254                 for (i = 0; i < buf->nr_pages; i++)
 255                         __free_page(buf->pages[i]);
 256                 kfree(buf->pages);
 257         } else
 258 #endif
 259                 vfree(buf->data);
 260         kfree(buf);
 261 }
 262
 263 static void fw_free_buf(struct firmware_buf *buf)
 264 {
 265         struct firmware_cache *fwc = buf->fwc;
 266         spin_lock(&fwc->lock);
 267         if (!kref_put(&buf->ref, __fw_free_buf))
 268                 spin_unlock(&fwc->lock);
 269 }
 270
 271 /* direct firmware loading support */
 272 static char fw_path_para[256];
 273 static const char * const fw_path[] = {
 274         fw_path_para,
 275         "/lib/firmware/updates/" UTS_RELEASE,
 276         "/lib/firmware/updates",
 277         "/lib/firmware/" UTS_RELEASE,
 278         "/lib/firmware"
 279 };
 280
 281 /*
 282  * Typical usage is that passing 'firmware_class.path=$CUSTOMIZED_PATH'
 283  * from kernel command line because firmware_class is generally built in
 284  * kernel instead of module.
 285  */
 286 module_param_string(path, fw_path_para, sizeof(fw_path_para), 0644);
 287 MODULE_PARM_DESC(path, "customized firmware image search path with a higher priority than default path");
 288
 289 static int fw_read_file_contents(struct file *file, struct firmware_buf *fw_buf)
 290 {
 291         int size;
 292         char *buf;
 293         int rc;
 294
 295         if (!S_ISREG(file_inode(file)->i_mode))
 296                 return -EINVAL;
 297         size = i_size_read(file_inode(file));
 298         if (size <= 0)
 299                 return -EINVAL;
 300         buf = vmalloc(size);
 301         if (!buf)
 302                 return -ENOMEM;
 303         rc = kernel_read(file, 0, buf, size);
 304         if (rc != size) {
 305                 if (rc > 0)
 306                         rc = -EIO;
 307                 goto fail;
 308         }
 309         rc = security_kernel_fw_from_file(file, buf, size);
 310         if (rc)
 311                 goto fail;
 312         fw_buf->data = buf;
 313         fw_buf->size = size;
 314         return 0;
 315 fail:
 316         vfree(buf);
 317         return rc;
 318 }
 319
 320 static int fw_get_filesystem_firmware(struct device *device,
 321                                        struct firmware_buf *buf)
 322 {
 323         int i;
 324         int rc = -ENOENT;
 325         char *path = __getname();
 326
 327         for (i = 0; i < ARRAY_SIZE(fw_path); i++) {
 328                 struct file *file;
 329
 330                 /* skip the unset customized path */
 331                 if (!fw_path[i][0])
 332                         continue;
 333
 334                 snprintf(path, PATH_MAX, "%s/%s", fw_path[i], buf->fw_id);
 335
 336                 file = filp_open(path, O_RDONLY, 0);
 337                 if (IS_ERR(file))
 338                         continue;
 339                 rc = fw_read_file_contents(file, buf);
 340                 fput(file);
 341                 if (rc)
 342                         dev_warn(device, "firmware, attempted to load %s, but failed with error %d\n",
 343                                 path, rc);
 344                 else
 345                         break;
 346         }
 347         __putname(path);
 348
 349         if (!rc) {
 350                 dev_dbg(device, "firmware: direct-loading firmware %s\n",
 351                         buf->fw_id);
 352                 mutex_lock(&fw_lock);
 353                 set_bit(FW_STATUS_DONE, &buf->status);
 354                 complete_all(&buf->completion);
 355                 mutex_unlock(&fw_lock);
 356         }
 357
 358         return rc;
 359 }
 360
 361 /* firmware holds the ownership of pages */
 362 static void firmware_free_data(const struct firmware *fw)
 363 {
 364         /* Loaded directly? */
 365         if (!fw->priv) {
 366                 vfree(fw->data);
 367                 return;
 368         }
 369         fw_free_buf(fw->priv);
 370 }
 371
 372 /* store the pages buffer info firmware from buf */
 373 static void fw_set_page_data(struct firmware_buf *buf, struct firmware *fw)
 374 {
 375         fw->priv = buf;
 376 #ifdef CONFIG_FW_LOADER_USER_HELPER
 377         fw->pages = buf->pages;
 378 #endif
 379         fw->size = buf->size;
 380         fw->data = buf->data;
 381
 382         pr_debug("%s: fw-%s buf=%p data=%p size=%u\n",
 383                  __func__, buf->fw_id, buf, buf->data,
 384                  (unsigned int)buf->size);
 385 }
 386
 387 #ifdef CONFIG_PM_SLEEP
 388 static void fw_name_devm_release(struct device *dev, void *res)
 389 {
 390         struct fw_name_devm *fwn = res;
 391
 392         if (fwn->magic == (unsigned long)&fw_cache)
 393                 pr_debug("%s: fw_name-%s devm-%p released\n",
 394                                 __func__, fwn->name, res);
 395 }
 396
 397 static int fw_devm_match(struct device *dev, void *res,
 398                 void *match_data)
 399 {
 400         struct fw_name_devm *fwn = res;
 401
 402         return (fwn->magic == (unsigned long)&fw_cache) &&
 403                 !strcmp(fwn->name, match_data);
 404 }
 405
 406 static struct fw_name_devm *fw_find_devm_name(struct device *dev,
 407                 const char *name)
 408 {
 409         struct fw_name_devm *fwn;
 410
 411         fwn = devres_find(dev, fw_name_devm_release,
 412                           fw_devm_match, (void *)name);
 413         return fwn;
 414 }
 415
 416 /* add firmware name into devres list */
 417 static int fw_add_devm_name(struct device *dev, const char *name)
 418 {
 419         struct fw_name_devm *fwn;
 420
 421         fwn = fw_find_devm_name(dev, name);
 422         if (fwn)
 423                 return 1;
 424
 425         fwn = devres_alloc(fw_name_devm_release, sizeof(struct fw_name_devm) +
 426                            strlen(name) + 1, GFP_KERNEL);
 427         if (!fwn)
 428                 return -ENOMEM;
 429
 430         fwn->magic = (unsigned long)&fw_cache;
 431         strcpy(fwn->name, name);
 432         devres_add(dev, fwn);
 433
 434         return 0;
 435 }
 436 #else
 437 static int fw_add_devm_name(struct device *dev, const char *name)
 438 {
 439         return 0;
 440 }
 441 #endif
 442
 443
 444 /*
 445  * user-mode helper code
 446  */
 447 #ifdef CONFIG_FW_LOADER_USER_HELPER
 448 struct firmware_priv {
 449         bool nowait;
 450         struct device dev;
 451         struct firmware_buf *buf;
 452         struct firmware *fw;
 453 };
 454
 455 static struct firmware_priv *to_firmware_priv(struct device *dev)
 456 {
 457         return container_of(dev, struct firmware_priv, dev);
 458 }
 459
 460 static void __fw_load_abort(struct firmware_buf *buf)
 461 {
 462         /*
 463          * There is a small window in which user can write to 'loading'
 464          * between loading done and disappearance of 'loading'
 465          */
 466         if (test_bit(FW_STATUS_DONE, &buf->status))
 467                 return;
 468
 469         list_del_init(&buf->pending_list);
 470         set_bit(FW_STATUS_ABORT, &buf->status);
 471         complete_all(&buf->completion);
 472 }
 473
 474 static void fw_load_abort(struct firmware_priv *fw_priv)
 475 {
 476         struct firmware_buf *buf = fw_priv->buf;
 477
 478         __fw_load_abort(buf);
 479
 480         /* avoid user action after loading abort */
 481         fw_priv->buf = NULL;
 482 }
 483
 484 #define is_fw_load_aborted(buf) \
 485         test_bit(FW_STATUS_ABORT, &(buf)->status)
 486
 487 static LIST_HEAD(pending_fw_head);
 488
 489 /* reboot notifier for avoid deadlock with usermode_lock */
 490 static int fw_shutdown_notify(struct notifier_block *unused1,
 491                               unsigned long unused2, void *unused3)
 492 {
 493         mutex_lock(&fw_lock);
 494         while (!list_empty(&pending_fw_head))
 495                 __fw_load_abort(list_first_entry(&pending_fw_head,
 496                                                struct firmware_buf,
 497                                                pending_list));
 498         mutex_unlock(&fw_lock);
 499         return NOTIFY_DONE;
 500 }
 501
 502 static struct notifier_block fw_shutdown_nb = {
 503         .notifier_call = fw_shutdown_notify,
 504 };
 505
 506 static ssize_t timeout_show(struct class *class, struct class_attribute *attr,
 507                             char *buf)
 508 {
 509         return sprintf(buf, "%d\n", loading_timeout);
 510 }
 511
 512 /**
 513  * firmware_timeout_store - set number of seconds to wait for firmware
 514  * @class: device class pointer
 515  * @attr: device attribute pointer
 516  * @buf: buffer to scan for timeout value
 517  * @count: number of bytes in @buf
 518  *
 519  *      Sets the number of seconds to wait for the firmware.  Once
 520  *      this expires an error will be returned to the driver and no
 521  *      firmware will be provided.
 522  *
 523  *      Note: zero means 'wait forever'.
 524  **/
 525 static ssize_t timeout_store(struct class *class, struct class_attribute *attr,
 526                              const char *buf, size_t count)
 527 {
 528         loading_timeout = simple_strtol(buf, NULL, 10);
 529         if (loading_timeout < 0)
 530                 loading_timeout = 0;
 531
 532         return count;
 533 }
 534
 535 static struct class_attribute firmware_class_attrs[] = {
 536         __ATTR_RW(timeout),
 537         __ATTR_NULL
 538 };
 539
 540 static void fw_dev_release(struct device *dev)
 541 {
 542         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 543
 544         kfree(fw_priv);
 545 }
 546
 547 static int firmware_uevent(struct device *dev, struct kobj_uevent_env *env)
 548 {
 549         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 550
 551         if (add_uevent_var(env, "FIRMWARE=%s", fw_priv->buf->fw_id))
 552                 return -ENOMEM;
 553         if (add_uevent_var(env, "TIMEOUT=%i", loading_timeout))
 554                 return -ENOMEM;
 555         if (add_uevent_var(env, "ASYNC=%d", fw_priv->nowait))
 556                 return -ENOMEM;
 557
 558         return 0;
 559 }
 560
 561 static struct class firmware_class = {
 562         .name           = "firmware",
 563         .class_attrs    = firmware_class_attrs,
 564         .dev_uevent     = firmware_uevent,
 565         .dev_release    = fw_dev_release,
 566 };
 567
 568 static ssize_t firmware_loading_show(struct device *dev,
 569                                      struct device_attribute *attr, char *buf)
 570 {
 571         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 572         int loading = 0;
 573
 574         mutex_lock(&fw_lock);
 575         if (fw_priv->buf)
 576                 loading = test_bit(FW_STATUS_LOADING, &fw_priv->buf->status);
 577         mutex_unlock(&fw_lock);
 578
 579         return sprintf(buf, "%d\n", loading);
 580 }
 581
 582 /* Some architectures don't have PAGE_KERNEL_RO */
 583 #ifndef PAGE_KERNEL_RO
 584 #define PAGE_KERNEL_RO PAGE_KERNEL
 585 #endif
 586
 587 /* one pages buffer should be mapped/unmapped only once */
 588 static int fw_map_pages_buf(struct firmware_buf *buf)
 589 {
 590         if (!buf->is_paged_buf)
 591                 return 0;
 592
 593         vunmap(buf->data);
 594         buf->data = vmap(buf->pages, buf->nr_pages, 0, PAGE_KERNEL_RO);
 595         if (!buf->data)
 596                 return -ENOMEM;
 597         return 0;
 598 }
 599
 600 /**
 601  * firmware_loading_store - set value in the 'loading' control file
 602  * @dev: device pointer
 603  * @attr: device attribute pointer
 604  * @buf: buffer to scan for loading control value
 605  * @count: number of bytes in @buf
 606  *
 607  *      The relevant values are:
 608  *
 609  *       1: Start a load, discarding any previous partial load.
 610  *       0: Conclude the load and hand the data to the driver code.
 611  *      -1: Conclude the load with an error and discard any written data.
 612  **/
 613 static ssize_t firmware_loading_store(struct device *dev,
 614                                       struct device_attribute *attr,
 615                                       const char *buf, size_t count)
 616 {
 617         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 618         struct firmware_buf *fw_buf;
 619         ssize_t written = count;
 620         int loading = simple_strtol(buf, NULL, 10);
 621         int i;
 622
 623         mutex_lock(&fw_lock);
 624         fw_buf = fw_priv->buf;
 625         if (!fw_buf)
 626                 goto out;
 627
 628         switch (loading) {
 629         case 1:
 630                 /* discarding any previous partial load */
 631                 if (!test_bit(FW_STATUS_DONE, &fw_buf->status)) {
 632                         for (i = 0; i < fw_buf->nr_pages; i++)
 633                                 __free_page(fw_buf->pages[i]);
 634                         kfree(fw_buf->pages);
 635                         fw_buf->pages = NULL;
 636                         fw_buf->page_array_size = 0;
 637                         fw_buf->nr_pages = 0;
 638                         set_bit(FW_STATUS_LOADING, &fw_buf->status);
 639                 }
 640                 break;
 641         case 0:
 642                 if (test_bit(FW_STATUS_LOADING, &fw_buf->status)) {
 643                         int rc;
 644
 645                         set_bit(FW_STATUS_DONE, &fw_buf->status);
 646                         clear_bit(FW_STATUS_LOADING, &fw_buf->status);
 647
 648                         /*
 649                          * Several loading requests may be pending on
 650                          * one same firmware buf, so let all requests
 651                          * see the mapped 'buf->data' once the loading
 652                          * is completed.
 653                          * */
 654                         rc = fw_map_pages_buf(fw_buf);
 655                         if (rc)
 656                                 dev_err(dev, "%s: map pages failed\n",
 657                                         __func__);
 658                         else
 659                                 rc = security_kernel_fw_from_file(NULL,
 660                                                 fw_buf->data, fw_buf->size);
 661
 662                         /*
 663                          * Same logic as fw_load_abort, only the DONE bit
 664                          * is ignored and we set ABORT only on failure.
 665                          */
 666                         list_del_init(&fw_buf->pending_list);
 667                         if (rc) {
 668                                 set_bit(FW_STATUS_ABORT, &fw_buf->status);
 669                                 written = rc;
 670                         }
 671                         complete_all(&fw_buf->completion);
 672                         break;
 673                 }
 674                 /* fallthrough */
 675         default:
 676                 dev_err(dev, "%s: unexpected value (%d)\n", __func__, loading);
 677                 /* fallthrough */
 678         case -1:
 679                 fw_load_abort(fw_priv);
 680                 break;
 681         }
 682 out:
 683         mutex_unlock(&fw_lock);
 684         return written;
 685 }
 686
 687 static DEVICE_ATTR(loading, 0644, firmware_loading_show, firmware_loading_store);
 688
 689 static ssize_t firmware_data_read(struct file *filp, struct kobject *kobj,
 690                                   struct bin_attribute *bin_attr,
 691                                   char *buffer, loff_t offset, size_t count)
 692 {
 693         struct device *dev = kobj_to_dev(kobj);
 694         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 695         struct firmware_buf *buf;
 696         ssize_t ret_count;
 697
 698         mutex_lock(&fw_lock);
 699         buf = fw_priv->buf;
 700         if (!buf || test_bit(FW_STATUS_DONE, &buf->status)) {
 701                 ret_count = -ENODEV;
 702                 goto out;
 703         }
 704         if (offset > buf->size) {
 705                 ret_count = 0;
 706                 goto out;
 707         }
 708         if (count > buf->size - offset)
 709                 count = buf->size - offset;
 710
 711         ret_count = count;
 712
 713         while (count) {
 714                 void *page_data;
 715                 int page_nr = offset >> PAGE_SHIFT;
 716                 int page_ofs = offset & (PAGE_SIZE-1);
 717                 int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
 718
 719                 page_data = kmap(buf->pages[page_nr]);
 720
 721                 memcpy(buffer, page_data + page_ofs, page_cnt);
 722
 723                 kunmap(buf->pages[page_nr]);
 724                 buffer += page_cnt;
 725                 offset += page_cnt;
 726                 count -= page_cnt;
 727         }
 728 out:
 729         mutex_unlock(&fw_lock);
 730         return ret_count;
 731 }
 732
 733 static int fw_realloc_buffer(struct firmware_priv *fw_priv, int min_size)
 734 {
 735         struct firmware_buf *buf = fw_priv->buf;
 736         int pages_needed = PAGE_ALIGN(min_size) >> PAGE_SHIFT;
 737
 738         /* If the array of pages is too small, grow it... */
 739         if (buf->page_array_size < pages_needed) {
 740                 int new_array_size = max(pages_needed,
 741                                          buf->page_array_size * 2);
 742                 struct page **new_pages;
 743
 744                 new_pages = kmalloc(new_array_size * sizeof(void *),
 745                                     GFP_KERNEL);
 746                 if (!new_pages) {
 747                         fw_load_abort(fw_priv);
 748                         return -ENOMEM;
 749                 }
 750                 memcpy(new_pages, buf->pages,
 751                        buf->page_array_size * sizeof(void *));
 752                 memset(&new_pages[buf->page_array_size], 0, sizeof(void *) *
 753                        (new_array_size - buf->page_array_size));
 754                 kfree(buf->pages);
 755                 buf->pages = new_pages;
 756                 buf->page_array_size = new_array_size;
 757         }
 758
 759         while (buf->nr_pages < pages_needed) {
 760                 buf->pages[buf->nr_pages] =
 761                         alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
 762
 763                 if (!buf->pages[buf->nr_pages]) {
 764                         fw_load_abort(fw_priv);
 765                         return -ENOMEM;
 766                 }
 767                 buf->nr_pages++;
 768         }
 769         return 0;
 770 }
 771
 772 /**
 773  * firmware_data_write - write method for firmware
 774  * @filp: open sysfs file
 775  * @kobj: kobject for the device
 776  * @bin_attr: bin_attr structure
 777  * @buffer: buffer being written
 778  * @offset: buffer offset for write in total data store area
 779  * @count: buffer size
 780  *
 781  *      Data written to the 'data' attribute will be later handed to
 782  *      the driver as a firmware image.
 783  **/
 784 static ssize_t firmware_data_write(struct file *filp, struct kobject *kobj,
 785                                    struct bin_attribute *bin_attr,
 786                                    char *buffer, loff_t offset, size_t count)
 787 {
 788         struct device *dev = kobj_to_dev(kobj);
 789         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 790         struct firmware_buf *buf;
 791         ssize_t retval;
 792
 793         if (!capable(CAP_SYS_RAWIO))
 794                 return -EPERM;
 795
 796         mutex_lock(&fw_lock);
 797         buf = fw_priv->buf;
 798         if (!buf || test_bit(FW_STATUS_DONE, &buf->status)) {
 799                 retval = -ENODEV;
 800                 goto out;
 801         }
 802
 803         retval = fw_realloc_buffer(fw_priv, offset + count);
 804         if (retval)
 805                 goto out;
 806
 807         retval = count;
 808
 809         while (count) {
 810                 void *page_data;
 811                 int page_nr = offset >> PAGE_SHIFT;
 812                 int page_ofs = offset & (PAGE_SIZE - 1);
 813                 int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
 814
 815                 page_data = kmap(buf->pages[page_nr]);
 816
 817                 memcpy(page_data + page_ofs, buffer, page_cnt);
 818
 819                 kunmap(buf->pages[page_nr]);
 820                 buffer += page_cnt;
 821                 offset += page_cnt;
 822                 count -= page_cnt;
 823         }
 824
 825         buf->size = max_t(size_t, offset, buf->size);
 826 out:
 827         mutex_unlock(&fw_lock);
 828         return retval;
 829 }
 830
 831 static struct bin_attribute firmware_attr_data = {
 832         .attr = { .name = "data", .mode = 0644 },
 833         .size = 0,
 834         .read = firmware_data_read,
 835         .write = firmware_data_write,
 836 };
 837
 838 static struct firmware_priv *
 839 fw_create_instance(struct firmware *firmware, const char *fw_name,
 840                    struct device *device, unsigned int opt_flags)
 841 {
 842         struct firmware_priv *fw_priv;
 843         struct device *f_dev;
 844
 845         fw_priv = kzalloc(sizeof(*fw_priv), GFP_KERNEL);
 846         if (!fw_priv) {
 847                 fw_priv = ERR_PTR(-ENOMEM);
 848                 goto exit;
 849         }
 850
 851         fw_priv->nowait = !!(opt_flags & FW_OPT_NOWAIT);
 852         fw_priv->fw = firmware;
 853         f_dev = &fw_priv->dev;
 854
 855         device_initialize(f_dev);
 856         dev_set_name(f_dev, "%s", fw_name);
 857         f_dev->parent = device;
 858         f_dev->class = &firmware_class;
 859 exit:
 860         return fw_priv;
 861 }
 862
 863 /* load a firmware via user helper */
 864 static int _request_firmware_load(struct firmware_priv *fw_priv,
 865                                   unsigned int opt_flags, long timeout)
 866 {
 867         int retval = 0;
 868         struct device *f_dev = &fw_priv->dev;
 869         struct firmware_buf *buf = fw_priv->buf;
 870
 871         /* fall back on userspace loading */
 872         buf->is_paged_buf = true;
 873
 874         dev_set_uevent_suppress(f_dev, true);
 875
 876         retval = device_add(f_dev);
 877         if (retval) {
 878                 dev_err(f_dev, "%s: device_register failed\n", __func__);
 879                 goto err_put_dev;
 880         }
 881
 882         retval = device_create_bin_file(f_dev, &firmware_attr_data);
 883         if (retval) {
 884                 dev_err(f_dev, "%s: sysfs_create_bin_file failed\n", __func__);
 885                 goto err_del_dev;
 886         }
 887
 888         mutex_lock(&fw_lock);
 889         list_add(&buf->pending_list, &pending_fw_head);
 890         mutex_unlock(&fw_lock);
 891
 892         retval = device_create_file(f_dev, &dev_attr_loading);
 893         if (retval) {
 894                 mutex_lock(&fw_lock);
 895                 list_del_init(&buf->pending_list);
 896                 mutex_unlock(&fw_lock);
 897                 dev_err(f_dev, "%s: device_create_file failed\n", __func__);
 898                 goto err_del_bin_attr;
 899         }
 900
 901         if (opt_flags & FW_OPT_UEVENT) {
 902                 buf->need_uevent = true;
 903                 dev_set_uevent_suppress(f_dev, false);
 904                 dev_dbg(f_dev, "firmware: requesting %s\n", buf->fw_id);
 905                 kobject_uevent(&fw_priv->dev.kobj, KOBJ_ADD);
 906         } else {
 907                 timeout = MAX_JIFFY_OFFSET;
 908         }
 909
 910         retval = wait_for_completion_interruptible_timeout(&buf->completion,
 911                         timeout);
 912         if (retval == -ERESTARTSYS || !retval) {
 913                 mutex_lock(&fw_lock);
 914                 fw_load_abort(fw_priv);
 915                 mutex_unlock(&fw_lock);
 916         }
 917
 918         if (is_fw_load_aborted(buf))
 919                 retval = -EAGAIN;
 920         else if (!buf->data)
 921                 retval = -ENOMEM;
 922
 923         device_remove_file(f_dev, &dev_attr_loading);
 924 err_del_bin_attr:
 925         device_remove_bin_file(f_dev, &firmware_attr_data);
 926 err_del_dev:
 927         device_del(f_dev);
 928 err_put_dev:
 929         put_device(f_dev);
 930         return retval;
 931 }
 932
 933 static int fw_load_from_user_helper(struct firmware *firmware,
 934                                     const char *name, struct device *device,
 935                                     unsigned int opt_flags, long timeout)
 936 {
 937         struct firmware_priv *fw_priv;
 938
 939         fw_priv = fw_create_instance(firmware, name, device, opt_flags);
 940         if (IS_ERR(fw_priv))
 941                 return PTR_ERR(fw_priv);
 942
 943         fw_priv->buf = firmware->priv;
 944         return _request_firmware_load(fw_priv, opt_flags, timeout);
 945 }
 946
 947 #ifdef CONFIG_PM_SLEEP
 948 /* kill pending requests without uevent to avoid blocking suspend */
 949 static void kill_requests_without_uevent(void)
 950 {
 951         struct firmware_buf *buf;
 952         struct firmware_buf *next;
 953
 954         mutex_lock(&fw_lock);
 955         list_for_each_entry_safe(buf, next, &pending_fw_head, pending_list) {
 956                 if (!buf->need_uevent)
 957                          __fw_load_abort(buf);
 958         }
 959         mutex_unlock(&fw_lock);
 960 }
 961 #endif
 962
 963 #else /* CONFIG_FW_LOADER_USER_HELPER */
 964 static inline int
 965 fw_load_from_user_helper(struct firmware *firmware, const char *name,
 966                          struct device *device, unsigned int opt_flags,
 967                          long timeout)
 968 {
 969         return -ENOENT;
 970 }
 971
 972 /* No abort during direct loading */
 973 #define is_fw_load_aborted(buf) false
 974
 975 #ifdef CONFIG_PM_SLEEP
 976 static inline void kill_requests_without_uevent(void) { }
 977 #endif
 978
 979 #endif /* CONFIG_FW_LOADER_USER_HELPER */
 980
 981
 982 /* wait until the shared firmware_buf becomes ready (or error) */
 983 static int sync_cached_firmware_buf(struct firmware_buf *buf)
 984 {
 985         int ret = 0;
 986
 987         mutex_lock(&fw_lock);
 988         while (!test_bit(FW_STATUS_DONE, &buf->status)) {
 989                 if (is_fw_load_aborted(buf)) {
 990                         ret = -ENOENT;
 991                         break;
 992                 }
 993                 mutex_unlock(&fw_lock);
 994                 ret = wait_for_completion_interruptible(&buf->completion);
 995                 mutex_lock(&fw_lock);
 996         }
 997         mutex_unlock(&fw_lock);
 998         return ret;
 999 }
1000
1001 /* prepare firmware and firmware_buf structs;
1002  * return 0 if a firmware is already assigned, 1 if need to load one,
1003  * or a negative error code
1004  */
1005 static int
1006 _request_firmware_prepare(struct firmware **firmware_p, const char *name,
1007                           struct device *device)
1008 {
1009         struct firmware *firmware;
1010         struct firmware_buf *buf;
1011         int ret;
1012
1013         *firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
1014         if (!firmware) {
1015                 dev_err(device, "%s: kmalloc(struct firmware) failed\n",
1016                         __func__);
1017                 return -ENOMEM;
1018         }
1019
1020         if (fw_get_builtin_firmware(firmware, name)) {
1021                 dev_dbg(device, "firmware: using built-in firmware %s\n", name);
1022                 return 0; /* assigned */
1023         }
1024
1025         ret = fw_lookup_and_allocate_buf(name, &fw_cache, &buf);
1026
1027         /*
1028          * bind with 'buf' now to avoid warning in failure path
1029          * of requesting firmware.
1030          */
1031         firmware->priv = buf;
1032
1033         if (ret > 0) {
1034                 ret = sync_cached_firmware_buf(buf);
1035                 if (!ret) {
1036                         fw_set_page_data(buf, firmware);
1037                         return 0; /* assigned */
1038                 }
1039         }
1040
1041         if (ret < 0)
1042                 return ret;
1043         return 1; /* need to load */
1044 }
1045
1046 static int assign_firmware_buf(struct firmware *fw, struct device *device,
1047                                unsigned int opt_flags)
1048 {
1049         struct firmware_buf *buf = fw->priv;
1050
1051         mutex_lock(&fw_lock);
1052         if (!buf->size || is_fw_load_aborted(buf)) {
1053                 mutex_unlock(&fw_lock);
1054                 return -ENOENT;
1055         }
1056
1057         /*
1058          * add firmware name into devres list so that we can auto cache
1059          * and uncache firmware for device.
1060          *
1061          * device may has been deleted already, but the problem
1062          * should be fixed in devres or driver core.
1063          */
1064         /* don't cache firmware handled without uevent */
1065         if (device && (opt_flags & FW_OPT_UEVENT))
1066                 fw_add_devm_name(device, buf->fw_id);
1067
1068         /*
1069          * After caching firmware image is started, let it piggyback
1070          * on request firmware.
1071          */
1072         if (buf->fwc->state == FW_LOADER_START_CACHE) {
1073                 if (fw_cache_piggyback_on_request(buf->fw_id))
1074                         kref_get(&buf->ref);
1075         }
1076
1077         /* pass the pages buffer to driver at the last minute */
1078         fw_set_page_data(buf, fw);
1079         mutex_unlock(&fw_lock);
1080         return 0;
1081 }
1082
1083 /* called from request_firmware() and request_firmware_work_func() */
1084 static int
1085 _request_firmware(const struct firmware **firmware_p, const char *name,
1086                   struct device *device, unsigned int opt_flags)
1087 {
1088         struct firmware *fw;
1089         long timeout;
1090         int ret;
1091
1092         if (!firmware_p)
1093                 return -EINVAL;
1094
1095         if (!name || name[0] == '\0')
1096                 return -EINVAL;
1097
1098         ret = _request_firmware_prepare(&fw, name, device);
1099         if (ret <= 0) /* error or already assigned */
1100                 goto out;
1101
1102         ret = 0;
1103         timeout = firmware_loading_timeout();
1104         if (opt_flags & FW_OPT_NOWAIT) {
1105                 timeout = usermodehelper_read_lock_wait(timeout);
1106                 if (!timeout) {
1107                         dev_dbg(device, "firmware: %s loading timed out\n",
1108                                 name);
1109                         ret = -EBUSY;
1110                         goto out;
1111                 }
1112         } else {
1113                 ret = usermodehelper_read_trylock();
1114                 if (WARN_ON(ret)) {
1115                         dev_err(device, "firmware: %s will not be loaded\n",
1116                                 name);
1117                         goto out;
1118                 }
1119         }
1120
1121         ret = fw_get_filesystem_firmware(device, fw->priv);
1122         if (ret) {
1123                 if (!(opt_flags & FW_OPT_NO_WARN))
1124                         dev_warn(device,
1125                                  "Direct firmware load for %s failed with error %d\n",
1126                                  name, ret);
1127                 if (opt_flags & FW_OPT_USERHELPER) {
1128                         dev_warn(device, "Falling back to user helper\n");
1129                         ret = fw_load_from_user_helper(fw, name, device,
1130                                                        opt_flags, timeout);
1131                 }
1132         }
1133
1134         if (!ret)
1135                 ret = assign_firmware_buf(fw, device, opt_flags);
1136
1137         usermodehelper_read_unlock();
1138
1139  out:
1140         if (ret < 0) {
1141                 release_firmware(fw);
1142                 fw = NULL;
1143         }
1144
1145         *firmware_p = fw;
1146         return ret;
1147 }
1148
1149 /**
1150  * request_firmware: - send firmware request and wait for it
1151  * @firmware_p: pointer to firmware image
1152  * @name: name of firmware file
1153  * @device: device for which firmware is being loaded
1154  *
1155  *      @firmware_p will be used to return a firmware image by the name
1156  *      of @name for device @device.
1157  *
1158  *      Should be called from user context where sleeping is allowed.
1159  *
1160  *      @name will be used as $FIRMWARE in the uevent environment and
1161  *      should be distinctive enough not to be confused with any other
1162  *      firmware image for this or any other device.
1163  *
1164  *      Caller must hold the reference count of @device.
1165  *
1166  *      The function can be called safely inside device's suspend and
1167  *      resume callback.
1168  **/
1169 int
1170 request_firmware(const struct firmware **firmware_p, const char *name,
1171                  struct device *device)
1172 {
1173         int ret;
1174
1175         /* Need to pin this module until return */
1176         __module_get(THIS_MODULE);
1177         ret = _request_firmware(firmware_p, name, device,
1178                                 FW_OPT_UEVENT | FW_OPT_FALLBACK);
1179         module_put(THIS_MODULE);
1180         return ret;
1181 }
1182 EXPORT_SYMBOL(request_firmware);
1183
1184 /**
1185  * request_firmware_direct: - load firmware directly without usermode helper
1186  * @firmware_p: pointer to firmware image
1187  * @name: name of firmware file
1188  * @device: device for which firmware is being loaded
1189  *
1190  * This function works pretty much like request_firmware(), but this doesn't
1191  * fall back to usermode helper even if the firmware couldn't be loaded
1192  * directly from fs.  Hence it's useful for loading optional firmwares, which
1193  * aren't always present, without extra long timeouts of udev.
1194  **/
1195 int request_firmware_direct(const struct firmware **firmware_p,
1196                             const char *name, struct device *device)
1197 {
1198         int ret;
1199         __module_get(THIS_MODULE);
1200         ret = _request_firmware(firmware_p, name, device,
1201                                 FW_OPT_UEVENT | FW_OPT_NO_WARN);
1202         module_put(THIS_MODULE);
1203         return ret;
1204 }
1205 EXPORT_SYMBOL_GPL(request_firmware_direct);
1206
1207 /**
1208  * release_firmware: - release the resource associated with a firmware image
1209  * @fw: firmware resource to release
1210  **/
1211 void release_firmware(const struct firmware *fw)
1212 {
1213         if (fw) {
1214                 if (!fw_is_builtin_firmware(fw))
1215                         firmware_free_data(fw);
1216                 kfree(fw);
1217         }
1218 }
1219 EXPORT_SYMBOL(release_firmware);
1220
1221 /* Async support */
1222 struct firmware_work {
1223         struct work_struct work;
1224         struct module *module;
1225         const char *name;
1226         struct device *device;
1227         void *context;
1228         void (*cont)(const struct firmware *fw, void *context);
1229         unsigned int opt_flags;
1230 };
1231
1232 static void request_firmware_work_func(struct work_struct *work)
1233 {
1234         struct firmware_work *fw_work;
1235         const struct firmware *fw;
1236
1237         fw_work = container_of(work, struct firmware_work, work);
1238
1239         _request_firmware(&fw, fw_work->name, fw_work->device,
1240                           fw_work->opt_flags);
1241         fw_work->cont(fw, fw_work->context);
1242         put_device(fw_work->device); /* taken in request_firmware_nowait() */
1243
1244         module_put(fw_work->module);
1245         kfree(fw_work);
1246 }
1247
1248 /**
1249  * request_firmware_nowait - asynchronous version of request_firmware
1250  * @module: module requesting the firmware
1251  * @uevent: sends uevent to copy the firmware image if this flag
1252  *      is non-zero else the firmware copy must be done manually.
1253  * @name: name of firmware file
1254  * @device: device for which firmware is being loaded
1255  * @gfp: allocation flags
1256  * @context: will be passed over to @cont, and
1257  *      @fw may be %NULL if firmware request fails.
1258  * @cont: function will be called asynchronously when the firmware
1259  *      request is over.
1260  *
1261  *      Caller must hold the reference count of @device.
1262  *
1263  *      Asynchronous variant of request_firmware() for user contexts:
1264  *              - sleep for as small periods as possible since it may
1265  *              increase kernel boot time of built-in device drivers
1266  *              requesting firmware in their ->probe() methods, if
1267  *              @gfp is GFP_KERNEL.
1268  *
1269  *              - can't sleep at all if @gfp is GFP_ATOMIC.
1270  **/
1271 int
1272 request_firmware_nowait(
1273         struct module *module, bool uevent,
1274         const char *name, struct device *device, gfp_t gfp, void *context,
1275         void (*cont)(const struct firmware *fw, void *context))
1276 {
1277         struct firmware_work *fw_work;
1278
1279         fw_work = kzalloc(sizeof (struct firmware_work), gfp);
1280         if (!fw_work)
1281                 return -ENOMEM;
1282
1283         fw_work->module = module;
1284         fw_work->name = name;
1285         fw_work->device = device;
1286         fw_work->context = context;
1287         fw_work->cont = cont;
1288         fw_work->opt_flags = FW_OPT_NOWAIT | FW_OPT_FALLBACK |
1289                 (uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER);
1290
1291         if (!try_module_get(module)) {
1292                 kfree(fw_work);
1293                 return -EFAULT;
1294         }
1295
1296         get_device(fw_work->device);
1297         INIT_WORK(&fw_work->work, request_firmware_work_func);
1298         schedule_work(&fw_work->work);
1299         return 0;
1300 }
1301 EXPORT_SYMBOL(request_firmware_nowait);
1302
1303 #ifdef CONFIG_PM_SLEEP
1304 static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
1305
1306 /**
1307  * cache_firmware - cache one firmware image in kernel memory space
1308  * @fw_name: the firmware image name
1309  *
1310  * Cache firmware in kernel memory so that drivers can use it when
1311  * system isn't ready for them to request firmware image from userspace.
1312  * Once it returns successfully, driver can use request_firmware or its
1313  * nowait version to get the cached firmware without any interacting
1314  * with userspace
1315  *
1316  * Return 0 if the firmware image has been cached successfully
1317  * Return !0 otherwise
1318  *
1319  */
1320 static int cache_firmware(const char *fw_name)
1321 {
1322         int ret;
1323         const struct firmware *fw;
1324
1325         pr_debug("%s: %s\n", __func__, fw_name);
1326
1327         ret = request_firmware(&fw, fw_name, NULL);
1328         if (!ret)
1329                 kfree(fw);
1330
1331         pr_debug("%s: %s ret=%d\n", __func__, fw_name, ret);
1332
1333         return ret;
1334 }
1335
1336 static struct firmware_buf *fw_lookup_buf(const char *fw_name)
1337 {
1338         struct firmware_buf *tmp;
1339         struct firmware_cache *fwc = &fw_cache;
1340
1341         spin_lock(&fwc->lock);
1342         tmp = __fw_lookup_buf(fw_name);
1343         spin_unlock(&fwc->lock);
1344
1345         return tmp;
1346 }
1347
1348 /**
1349  * uncache_firmware - remove one cached firmware image
1350  * @fw_name: the firmware image name
1351  *
1352  * Uncache one firmware image which has been cached successfully
1353  * before.
1354  *
1355  * Return 0 if the firmware cache has been removed successfully
1356  * Return !0 otherwise
1357  *
1358  */
1359 static int uncache_firmware(const char *fw_name)
1360 {
1361         struct firmware_buf *buf;
1362         struct firmware fw;
1363
1364         pr_debug("%s: %s\n", __func__, fw_name);
1365
1366         if (fw_get_builtin_firmware(&fw, fw_name))
1367                 return 0;
1368
1369         buf = fw_lookup_buf(fw_name);
1370         if (buf) {
1371                 fw_free_buf(buf);
1372                 return 0;
1373         }
1374
1375         return -EINVAL;
1376 }
1377
1378 static struct fw_cache_entry *alloc_fw_cache_entry(const char *name)
1379 {
1380         struct fw_cache_entry *fce;
1381
1382         fce = kzalloc(sizeof(*fce) + strlen(name) + 1, GFP_ATOMIC);
1383         if (!fce)
1384                 goto exit;
1385
1386         strcpy(fce->name, name);
1387 exit:
1388         return fce;
1389 }
1390
1391 static int __fw_entry_found(const char *name)
1392 {
1393         struct firmware_cache *fwc = &fw_cache;
1394         struct fw_cache_entry *fce;
1395
1396         list_for_each_entry(fce, &fwc->fw_names, list) {
1397                 if (!strcmp(fce->name, name))
1398                         return 1;
1399         }
1400         return 0;
1401 }
1402
1403 static int fw_cache_piggyback_on_request(const char *name)
1404 {
1405         struct firmware_cache *fwc = &fw_cache;
1406         struct fw_cache_entry *fce;
1407         int ret = 0;
1408
1409         spin_lock(&fwc->name_lock);
1410         if (__fw_entry_found(name))
1411                 goto found;
1412
1413         fce = alloc_fw_cache_entry(name);
1414         if (fce) {
1415                 ret = 1;
1416                 list_add(&fce->list, &fwc->fw_names);
1417                 pr_debug("%s: fw: %s\n", __func__, name);
1418         }
1419 found:
1420         spin_unlock(&fwc->name_lock);
1421         return ret;
1422 }
1423
1424 static void free_fw_cache_entry(struct fw_cache_entry *fce)
1425 {
1426         kfree(fce);
1427 }
1428
1429 static void __async_dev_cache_fw_image(void *fw_entry,
1430                                        async_cookie_t cookie)
1431 {
1432         struct fw_cache_entry *fce = fw_entry;
1433         struct firmware_cache *fwc = &fw_cache;
1434         int ret;
1435
1436         ret = cache_firmware(fce->name);
1437         if (ret) {
1438                 spin_lock(&fwc->name_lock);
1439                 list_del(&fce->list);
1440                 spin_unlock(&fwc->name_lock);
1441
1442                 free_fw_cache_entry(fce);
1443         }
1444 }
1445
1446 /* called with dev->devres_lock held */
1447 static void dev_create_fw_entry(struct device *dev, void *res,
1448                                 void *data)
1449 {
1450         struct fw_name_devm *fwn = res;
1451         const char *fw_name = fwn->name;
1452         struct list_head *head = data;
1453         struct fw_cache_entry *fce;
1454
1455         fce = alloc_fw_cache_entry(fw_name);
1456         if (fce)
1457                 list_add(&fce->list, head);
1458 }
1459
1460 static int devm_name_match(struct device *dev, void *res,
1461                            void *match_data)
1462 {
1463         struct fw_name_devm *fwn = res;
1464         return (fwn->magic == (unsigned long)match_data);
1465 }
1466
1467 static void dev_cache_fw_image(struct device *dev, void *data)
1468 {
1469         LIST_HEAD(todo);
1470         struct fw_cache_entry *fce;
1471         struct fw_cache_entry *fce_next;
1472         struct firmware_cache *fwc = &fw_cache;
1473
1474         devres_for_each_res(dev, fw_name_devm_release,
1475                             devm_name_match, &fw_cache,
1476                             dev_create_fw_entry, &todo);
1477
1478         list_for_each_entry_safe(fce, fce_next, &todo, list) {
1479                 list_del(&fce->list);
1480
1481                 spin_lock(&fwc->name_lock);
1482                 /* only one cache entry for one firmware */
1483                 if (!__fw_entry_found(fce->name)) {
1484                         list_add(&fce->list, &fwc->fw_names);
1485                 } else {
1486                         free_fw_cache_entry(fce);
1487                         fce = NULL;
1488                 }
1489                 spin_unlock(&fwc->name_lock);
1490
1491                 if (fce)
1492                         async_schedule_domain(__async_dev_cache_fw_image,
1493                                               (void *)fce,
1494                                               &fw_cache_domain);
1495         }
1496 }
1497
1498 static void __device_uncache_fw_images(void)
1499 {
1500         struct firmware_cache *fwc = &fw_cache;
1501         struct fw_cache_entry *fce;
1502
1503         spin_lock(&fwc->name_lock);
1504         while (!list_empty(&fwc->fw_names)) {
1505                 fce = list_entry(fwc->fw_names.next,
1506                                 struct fw_cache_entry, list);
1507                 list_del(&fce->list);
1508                 spin_unlock(&fwc->name_lock);
1509
1510                 uncache_firmware(fce->name);
1511                 free_fw_cache_entry(fce);
1512
1513                 spin_lock(&fwc->name_lock);
1514         }
1515         spin_unlock(&fwc->name_lock);
1516 }
1517
1518 /**
1519  * device_cache_fw_images - cache devices' firmware
1520  *
1521  * If one device called request_firmware or its nowait version
1522  * successfully before, the firmware names are recored into the
1523  * device's devres link list, so device_cache_fw_images can call
1524  * cache_firmware() to cache these firmwares for the device,
1525  * then the device driver can load its firmwares easily at
1526  * time when system is not ready to complete loading firmware.
1527  */
1528 static void device_cache_fw_images(void)
1529 {
1530         struct firmware_cache *fwc = &fw_cache;
1531         int old_timeout;
1532         DEFINE_WAIT(wait);
1533
1534         pr_debug("%s\n", __func__);
1535
1536         /* cancel uncache work */
1537         cancel_delayed_work_sync(&fwc->work);
1538
1539         /*
1540          * use small loading timeout for caching devices' firmware
1541          * because all these firmware images have been loaded
1542          * successfully at lease once, also system is ready for
1543          * completing firmware loading now. The maximum size of
1544          * firmware in current distributions is about 2M bytes,
1545          * so 10 secs should be enough.
1546          */
1547         old_timeout = loading_timeout;
1548         loading_timeout = 10;
1549
1550         mutex_lock(&fw_lock);
1551         fwc->state = FW_LOADER_START_CACHE;
1552         dpm_for_each_dev(NULL, dev_cache_fw_image);
1553         mutex_unlock(&fw_lock);
1554
1555         /* wait for completion of caching firmware for all devices */
1556         async_synchronize_full_domain(&fw_cache_domain);
1557
1558         loading_timeout = old_timeout;
1559 }
1560
1561 /**
1562  * device_uncache_fw_images - uncache devices' firmware
1563  *
1564  * uncache all firmwares which have been cached successfully
1565  * by device_uncache_fw_images earlier
1566  */
1567 static void device_uncache_fw_images(void)
1568 {
1569         pr_debug("%s\n", __func__);
1570         __device_uncache_fw_images();
1571 }
1572
1573 static void device_uncache_fw_images_work(struct work_struct *work)
1574 {
1575         device_uncache_fw_images();
1576 }
1577
1578 /**
1579  * device_uncache_fw_images_delay - uncache devices firmwares
1580  * @delay: number of milliseconds to delay uncache device firmwares
1581  *
1582  * uncache all devices's firmwares which has been cached successfully
1583  * by device_cache_fw_images after @delay milliseconds.
1584  */
1585 static void device_uncache_fw_images_delay(unsigned long delay)
1586 {
1587         queue_delayed_work(system_power_efficient_wq, &fw_cache.work,
1588                            msecs_to_jiffies(delay));
1589 }
1590
1591 static int fw_pm_notify(struct notifier_block *notify_block,
1592                         unsigned long mode, void *unused)
1593 {
1594         switch (mode) {
1595         case PM_HIBERNATION_PREPARE:
1596         case PM_SUSPEND_PREPARE:
1597         case PM_RESTORE_PREPARE:
1598                 kill_requests_without_uevent();
1599                 device_cache_fw_images();
1600                 break;
1601
1602         case PM_POST_SUSPEND:
1603         case PM_POST_HIBERNATION:
1604         case PM_POST_RESTORE:
1605                 /*
1606                  * In case that system sleep failed and syscore_suspend is
1607                  * not called.
1608                  */
1609                 mutex_lock(&fw_lock);
1610                 fw_cache.state = FW_LOADER_NO_CACHE;
1611                 mutex_unlock(&fw_lock);
1612
1613                 device_uncache_fw_images_delay(10 * MSEC_PER_SEC);
1614                 break;
1615         }
1616
1617         return 0;
1618 }
1619
1620 /* stop caching firmware once syscore_suspend is reached */
1621 static int fw_suspend(void)
1622 {
1623         fw_cache.state = FW_LOADER_NO_CACHE;
1624         return 0;
1625 }
1626
1627 static struct syscore_ops fw_syscore_ops = {
1628         .suspend = fw_suspend,
1629 };
1630 #else
1631 static int fw_cache_piggyback_on_request(const char *name)
1632 {
1633         return 0;
1634 }
1635 #endif
1636
1637 static void __init fw_cache_init(void)
1638 {
1639         spin_lock_init(&fw_cache.lock);
1640         INIT_LIST_HEAD(&fw_cache.head);
1641         fw_cache.state = FW_LOADER_NO_CACHE;
1642
1643 #ifdef CONFIG_PM_SLEEP
1644         spin_lock_init(&fw_cache.name_lock);
1645         INIT_LIST_HEAD(&fw_cache.fw_names);
1646
1647         INIT_DELAYED_WORK(&fw_cache.work,
1648                           device_uncache_fw_images_work);
1649
1650         fw_cache.pm_notify.notifier_call = fw_pm_notify;
1651         register_pm_notifier(&fw_cache.pm_notify);
1652
1653         register_syscore_ops(&fw_syscore_ops);
1654 #endif
1655 }
1656
1657 static int __init firmware_class_init(void)
1658 {
1659         fw_cache_init();
1660 #ifdef CONFIG_FW_LOADER_USER_HELPER
1661         register_reboot_notifier(&fw_shutdown_nb);
1662         return class_register(&firmware_class);
1663 #else
1664         return 0;
1665 #endif
1666 }
1667
1668 static void __exit firmware_class_exit(void)
1669 {
1670 #ifdef CONFIG_PM_SLEEP
1671         unregister_syscore_ops(&fw_syscore_ops);
1672         unregister_pm_notifier(&fw_cache.pm_notify);
1673 #endif
1674 #ifdef CONFIG_FW_LOADER_USER_HELPER
1675         unregister_reboot_notifier(&fw_shutdown_nb);
1676         class_unregister(&firmware_class);
1677 #endif
1678 }
1679
1680 fs_initcall(firmware_class_init);
1681 module_exit(firmware_class_exit);