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