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                         if (fw_map_pages_buf(fw_buf))
 653                                 dev_err(dev, "%s: map pages failed\n",
 654                                         __func__);
 655                         list_del_init(&fw_buf->pending_list);
 656                         complete_all(&fw_buf->completion);
 657                         break;
 658                 }
 659                 /* fallthrough */
 660         default:
 661                 dev_err(dev, "%s: unexpected value (%d)\n", __func__, loading);
 662                 /* fallthrough */
 663         case -1:
 664                 fw_load_abort(fw_priv);
 665                 break;
 666         }
 667 out:
 668         mutex_unlock(&fw_lock);
 669         return count;
 670 }
 671
 672 static DEVICE_ATTR(loading, 0644, firmware_loading_show, firmware_loading_store);
 673
 674 static ssize_t firmware_data_read(struct file *filp, struct kobject *kobj,
 675                                   struct bin_attribute *bin_attr,
 676                                   char *buffer, loff_t offset, size_t count)
 677 {
 678         struct device *dev = kobj_to_dev(kobj);
 679         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 680         struct firmware_buf *buf;
 681         ssize_t ret_count;
 682
 683         mutex_lock(&fw_lock);
 684         buf = fw_priv->buf;
 685         if (!buf || test_bit(FW_STATUS_DONE, &buf->status)) {
 686                 ret_count = -ENODEV;
 687                 goto out;
 688         }
 689         if (offset > buf->size) {
 690                 ret_count = 0;
 691                 goto out;
 692         }
 693         if (count > buf->size - offset)
 694                 count = buf->size - offset;
 695
 696         ret_count = count;
 697
 698         while (count) {
 699                 void *page_data;
 700                 int page_nr = offset >> PAGE_SHIFT;
 701                 int page_ofs = offset & (PAGE_SIZE-1);
 702                 int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
 703
 704                 page_data = kmap(buf->pages[page_nr]);
 705
 706                 memcpy(buffer, page_data + page_ofs, page_cnt);
 707
 708                 kunmap(buf->pages[page_nr]);
 709                 buffer += page_cnt;
 710                 offset += page_cnt;
 711                 count -= page_cnt;
 712         }
 713 out:
 714         mutex_unlock(&fw_lock);
 715         return ret_count;
 716 }
 717
 718 static int fw_realloc_buffer(struct firmware_priv *fw_priv, int min_size)
 719 {
 720         struct firmware_buf *buf = fw_priv->buf;
 721         int pages_needed = ALIGN(min_size, PAGE_SIZE) >> PAGE_SHIFT;
 722
 723         /* If the array of pages is too small, grow it... */
 724         if (buf->page_array_size < pages_needed) {
 725                 int new_array_size = max(pages_needed,
 726                                          buf->page_array_size * 2);
 727                 struct page **new_pages;
 728
 729                 new_pages = kmalloc(new_array_size * sizeof(void *),
 730                                     GFP_KERNEL);
 731                 if (!new_pages) {
 732                         fw_load_abort(fw_priv);
 733                         return -ENOMEM;
 734                 }
 735                 memcpy(new_pages, buf->pages,
 736                        buf->page_array_size * sizeof(void *));
 737                 memset(&new_pages[buf->page_array_size], 0, sizeof(void *) *
 738                        (new_array_size - buf->page_array_size));
 739                 kfree(buf->pages);
 740                 buf->pages = new_pages;
 741                 buf->page_array_size = new_array_size;
 742         }
 743
 744         while (buf->nr_pages < pages_needed) {
 745                 buf->pages[buf->nr_pages] =
 746                         alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
 747
 748                 if (!buf->pages[buf->nr_pages]) {
 749                         fw_load_abort(fw_priv);
 750                         return -ENOMEM;
 751                 }
 752                 buf->nr_pages++;
 753         }
 754         return 0;
 755 }
 756
 757 /**
 758  * firmware_data_write - write method for firmware
 759  * @filp: open sysfs file
 760  * @kobj: kobject for the device
 761  * @bin_attr: bin_attr structure
 762  * @buffer: buffer being written
 763  * @offset: buffer offset for write in total data store area
 764  * @count: buffer size
 765  *
 766  *      Data written to the 'data' attribute will be later handed to
 767  *      the driver as a firmware image.
 768  **/
 769 static ssize_t firmware_data_write(struct file *filp, struct kobject *kobj,
 770                                    struct bin_attribute *bin_attr,
 771                                    char *buffer, loff_t offset, size_t count)
 772 {
 773         struct device *dev = kobj_to_dev(kobj);
 774         struct firmware_priv *fw_priv = to_firmware_priv(dev);
 775         struct firmware_buf *buf;
 776         ssize_t retval;
 777
 778         if (!capable(CAP_SYS_RAWIO))
 779                 return -EPERM;
 780
 781         mutex_lock(&fw_lock);
 782         buf = fw_priv->buf;
 783         if (!buf || test_bit(FW_STATUS_DONE, &buf->status)) {
 784                 retval = -ENODEV;
 785                 goto out;
 786         }
 787
 788         retval = fw_realloc_buffer(fw_priv, offset + count);
 789         if (retval)
 790                 goto out;
 791
 792         retval = count;
 793
 794         while (count) {
 795                 void *page_data;
 796                 int page_nr = offset >> PAGE_SHIFT;
 797                 int page_ofs = offset & (PAGE_SIZE - 1);
 798                 int page_cnt = min_t(size_t, PAGE_SIZE - page_ofs, count);
 799
 800                 page_data = kmap(buf->pages[page_nr]);
 801
 802                 memcpy(page_data + page_ofs, buffer, page_cnt);
 803
 804                 kunmap(buf->pages[page_nr]);
 805                 buffer += page_cnt;
 806                 offset += page_cnt;
 807                 count -= page_cnt;
 808         }
 809
 810         buf->size = max_t(size_t, offset, buf->size);
 811 out:
 812         mutex_unlock(&fw_lock);
 813         return retval;
 814 }
 815
 816 static struct bin_attribute firmware_attr_data = {
 817         .attr = { .name = "data", .mode = 0644 },
 818         .size = 0,
 819         .read = firmware_data_read,
 820         .write = firmware_data_write,
 821 };
 822
 823 static void firmware_class_timeout_work(struct work_struct *work)
 824 {
 825         struct firmware_priv *fw_priv = container_of(work,
 826                         struct firmware_priv, timeout_work.work);
 827
 828         mutex_lock(&fw_lock);
 829         fw_load_abort(fw_priv);
 830         mutex_unlock(&fw_lock);
 831 }
 832
 833 static struct firmware_priv *
 834 fw_create_instance(struct firmware *firmware, const char *fw_name,
 835                    struct device *device, unsigned int opt_flags)
 836 {
 837         struct firmware_priv *fw_priv;
 838         struct device *f_dev;
 839
 840         fw_priv = kzalloc(sizeof(*fw_priv), GFP_KERNEL);
 841         if (!fw_priv) {
 842                 dev_err(device, "%s: kmalloc failed\n", __func__);
 843                 fw_priv = ERR_PTR(-ENOMEM);
 844                 goto exit;
 845         }
 846
 847         fw_priv->nowait = !!(opt_flags & FW_OPT_NOWAIT);
 848         fw_priv->fw = firmware;
 849         INIT_DELAYED_WORK(&fw_priv->timeout_work,
 850                 firmware_class_timeout_work);
 851
 852         f_dev = &fw_priv->dev;
 853
 854         device_initialize(f_dev);
 855         dev_set_name(f_dev, "%s", fw_name);
 856         f_dev->parent = device;
 857         f_dev->class = &firmware_class;
 858 exit:
 859         return fw_priv;
 860 }
 861
 862 /* load a firmware via user helper */
 863 static int _request_firmware_load(struct firmware_priv *fw_priv,
 864                                   unsigned int opt_flags, long timeout)
 865 {
 866         int retval = 0;
 867         struct device *f_dev = &fw_priv->dev;
 868         struct firmware_buf *buf = fw_priv->buf;
 869
 870         /* fall back on userspace loading */
 871         buf->is_paged_buf = true;
 872
 873         dev_set_uevent_suppress(f_dev, true);
 874
 875         retval = device_add(f_dev);
 876         if (retval) {
 877                 dev_err(f_dev, "%s: device_register failed\n", __func__);
 878                 goto err_put_dev;
 879         }
 880
 881         retval = device_create_bin_file(f_dev, &firmware_attr_data);
 882         if (retval) {
 883                 dev_err(f_dev, "%s: sysfs_create_bin_file failed\n", __func__);
 884                 goto err_del_dev;
 885         }
 886
 887         mutex_lock(&fw_lock);
 888         list_add(&buf->pending_list, &pending_fw_head);
 889         mutex_unlock(&fw_lock);
 890
 891         retval = device_create_file(f_dev, &dev_attr_loading);
 892         if (retval) {
 893                 mutex_lock(&fw_lock);
 894                 list_del_init(&buf->pending_list);
 895                 mutex_unlock(&fw_lock);
 896                 dev_err(f_dev, "%s: device_create_file failed\n", __func__);
 897                 goto err_del_bin_attr;
 898         }
 899
 900         if (opt_flags & FW_OPT_UEVENT) {
 901                 buf->need_uevent = true;
 902                 dev_set_uevent_suppress(f_dev, false);
 903                 dev_dbg(f_dev, "firmware: requesting %s\n", buf->fw_id);
 904                 if (timeout != MAX_SCHEDULE_TIMEOUT)
 905                         queue_delayed_work(system_power_efficient_wq,
 906                                            &fw_priv->timeout_work, timeout);
 907
 908                 kobject_uevent(&fw_priv->dev.kobj, KOBJ_ADD);
 909         }
 910
 911         wait_for_completion(&buf->completion);
 912
 913         cancel_delayed_work_sync(&fw_priv->timeout_work);
 914         if (!buf->data)
 915                 retval = -ENOMEM;
 916
 917         device_remove_file(f_dev, &dev_attr_loading);
 918 err_del_bin_attr:
 919         device_remove_bin_file(f_dev, &firmware_attr_data);
 920 err_del_dev:
 921         device_del(f_dev);
 922 err_put_dev:
 923         put_device(f_dev);
 924         return retval;
 925 }
 926
 927 static int fw_load_from_user_helper(struct firmware *firmware,
 928                                     const char *name, struct device *device,
 929                                     unsigned int opt_flags, long timeout)
 930 {
 931         struct firmware_priv *fw_priv;
 932
 933         fw_priv = fw_create_instance(firmware, name, device, opt_flags);
 934         if (IS_ERR(fw_priv))
 935                 return PTR_ERR(fw_priv);
 936
 937         fw_priv->buf = firmware->priv;
 938         return _request_firmware_load(fw_priv, opt_flags, timeout);
 939 }
 940
 941 #ifdef CONFIG_PM_SLEEP
 942 /* kill pending requests without uevent to avoid blocking suspend */
 943 static void kill_requests_without_uevent(void)
 944 {
 945         struct firmware_buf *buf;
 946         struct firmware_buf *next;
 947
 948         mutex_lock(&fw_lock);
 949         list_for_each_entry_safe(buf, next, &pending_fw_head, pending_list) {
 950                 if (!buf->need_uevent)
 951                          __fw_load_abort(buf);
 952         }
 953         mutex_unlock(&fw_lock);
 954 }
 955 #endif
 956
 957 #else /* CONFIG_FW_LOADER_USER_HELPER */
 958 static inline int
 959 fw_load_from_user_helper(struct firmware *firmware, const char *name,
 960                          struct device *device, unsigned int opt_flags,
 961                          long timeout)
 962 {
 963         return -ENOENT;
 964 }
 965
 966 /* No abort during direct loading */
 967 #define is_fw_load_aborted(buf) false
 968
 969 #ifdef CONFIG_PM_SLEEP
 970 static inline void kill_requests_without_uevent(void) { }
 971 #endif
 972
 973 #endif /* CONFIG_FW_LOADER_USER_HELPER */
 974
 975
 976 /* wait until the shared firmware_buf becomes ready (or error) */
 977 static int sync_cached_firmware_buf(struct firmware_buf *buf)
 978 {
 979         int ret = 0;
 980
 981         mutex_lock(&fw_lock);
 982         while (!test_bit(FW_STATUS_DONE, &buf->status)) {
 983                 if (is_fw_load_aborted(buf)) {
 984                         ret = -ENOENT;
 985                         break;
 986                 }
 987                 mutex_unlock(&fw_lock);
 988                 wait_for_completion(&buf->completion);
 989                 mutex_lock(&fw_lock);
 990         }
 991         mutex_unlock(&fw_lock);
 992         return ret;
 993 }
 994
 995 /* prepare firmware and firmware_buf structs;
 996  * return 0 if a firmware is already assigned, 1 if need to load one,
 997  * or a negative error code
 998  */
 999 static int
1000 _request_firmware_prepare(struct firmware **firmware_p, const char *name,
1001                           struct device *device)
1002 {
1003         struct firmware *firmware;
1004         struct firmware_buf *buf;
1005         int ret;
1006
1007         *firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
1008         if (!firmware) {
1009                 dev_err(device, "%s: kmalloc(struct firmware) failed\n",
1010                         __func__);
1011                 return -ENOMEM;
1012         }
1013
1014         if (fw_get_builtin_firmware(firmware, name)) {
1015                 dev_dbg(device, "firmware: using built-in firmware %s\n", name);
1016                 return 0; /* assigned */
1017         }
1018
1019         ret = fw_lookup_and_allocate_buf(name, &fw_cache, &buf);
1020
1021         /*
1022          * bind with 'buf' now to avoid warning in failure path
1023          * of requesting firmware.
1024          */
1025         firmware->priv = buf;
1026
1027         if (ret > 0) {
1028                 ret = sync_cached_firmware_buf(buf);
1029                 if (!ret) {
1030                         fw_set_page_data(buf, firmware);
1031                         return 0; /* assigned */
1032                 }
1033         }
1034
1035         if (ret < 0)
1036                 return ret;
1037         return 1; /* need to load */
1038 }
1039
1040 static int assign_firmware_buf(struct firmware *fw, struct device *device,
1041                                unsigned int opt_flags)
1042 {
1043         struct firmware_buf *buf = fw->priv;
1044
1045         mutex_lock(&fw_lock);
1046         if (!buf->size || is_fw_load_aborted(buf)) {
1047                 mutex_unlock(&fw_lock);
1048                 return -ENOENT;
1049         }
1050
1051         /*
1052          * add firmware name into devres list so that we can auto cache
1053          * and uncache firmware for device.
1054          *
1055          * device may has been deleted already, but the problem
1056          * should be fixed in devres or driver core.
1057          */
1058         /* don't cache firmware handled without uevent */
1059         if (device && (opt_flags & FW_OPT_UEVENT))
1060                 fw_add_devm_name(device, buf->fw_id);
1061
1062         /*
1063          * After caching firmware image is started, let it piggyback
1064          * on request firmware.
1065          */
1066         if (buf->fwc->state == FW_LOADER_START_CACHE) {
1067                 if (fw_cache_piggyback_on_request(buf->fw_id))
1068                         kref_get(&buf->ref);
1069         }
1070
1071         /* pass the pages buffer to driver at the last minute */
1072         fw_set_page_data(buf, fw);
1073         mutex_unlock(&fw_lock);
1074         return 0;
1075 }
1076
1077 /* called from request_firmware() and request_firmware_work_func() */
1078 static int
1079 _request_firmware(const struct firmware **firmware_p, const char *name,
1080                   struct device *device, unsigned int opt_flags)
1081 {
1082         struct firmware *fw;
1083         long timeout;
1084         int ret;
1085
1086         if (!firmware_p)
1087                 return -EINVAL;
1088
1089         ret = _request_firmware_prepare(&fw, name, device);
1090         if (ret <= 0) /* error or already assigned */
1091                 goto out;
1092
1093         ret = 0;
1094         timeout = firmware_loading_timeout();
1095         if (opt_flags & FW_OPT_NOWAIT) {
1096                 timeout = usermodehelper_read_lock_wait(timeout);
1097                 if (!timeout) {
1098                         dev_dbg(device, "firmware: %s loading timed out\n",
1099                                 name);
1100                         ret = -EBUSY;
1101                         goto out;
1102                 }
1103         } else {
1104                 ret = usermodehelper_read_trylock();
1105                 if (WARN_ON(ret)) {
1106                         dev_err(device, "firmware: %s will not be loaded\n",
1107                                 name);
1108                         goto out;
1109                 }
1110         }
1111
1112         ret = fw_get_filesystem_firmware(device, fw->priv);
1113         if (ret) {
1114                 if (opt_flags & FW_OPT_FALLBACK) {
1115                         dev_warn(device,
1116                                  "Direct firmware load failed with error %d\n",
1117                                  ret);
1118                         dev_warn(device, "Falling back to user helper\n");
1119                         ret = fw_load_from_user_helper(fw, name, device,
1120                                                        opt_flags, timeout);
1121                 }
1122         }
1123
1124         if (!ret)
1125                 ret = assign_firmware_buf(fw, device, opt_flags);
1126
1127         usermodehelper_read_unlock();
1128
1129  out:
1130         if (ret < 0) {
1131                 release_firmware(fw);
1132                 fw = NULL;
1133         }
1134
1135         *firmware_p = fw;
1136         return ret;
1137 }
1138
1139 /**
1140  * request_firmware: - send firmware request and wait for it
1141  * @firmware_p: pointer to firmware image
1142  * @name: name of firmware file
1143  * @device: device for which firmware is being loaded
1144  *
1145  *      @firmware_p will be used to return a firmware image by the name
1146  *      of @name for device @device.
1147  *
1148  *      Should be called from user context where sleeping is allowed.
1149  *
1150  *      @name will be used as $FIRMWARE in the uevent environment and
1151  *      should be distinctive enough not to be confused with any other
1152  *      firmware image for this or any other device.
1153  *
1154  *      Caller must hold the reference count of @device.
1155  *
1156  *      The function can be called safely inside device's suspend and
1157  *      resume callback.
1158  **/
1159 int
1160 request_firmware(const struct firmware **firmware_p, const char *name,
1161                  struct device *device)
1162 {
1163         int ret;
1164
1165         /* Need to pin this module until return */
1166         __module_get(THIS_MODULE);
1167         ret = _request_firmware(firmware_p, name, device,
1168                                 FW_OPT_UEVENT | FW_OPT_FALLBACK);
1169         module_put(THIS_MODULE);
1170         return ret;
1171 }
1172 EXPORT_SYMBOL(request_firmware);
1173
1174 #ifdef CONFIG_FW_LOADER_USER_HELPER
1175 /**
1176  * request_firmware: - load firmware directly without usermode helper
1177  * @firmware_p: pointer to firmware image
1178  * @name: name of firmware file
1179  * @device: device for which firmware is being loaded
1180  *
1181  * This function works pretty much like request_firmware(), but this doesn't
1182  * fall back to usermode helper even if the firmware couldn't be loaded
1183  * directly from fs.  Hence it's useful for loading optional firmwares, which
1184  * aren't always present, without extra long timeouts of udev.
1185  **/
1186 int request_firmware_direct(const struct firmware **firmware_p,
1187                             const char *name, struct device *device)
1188 {
1189         int ret;
1190         __module_get(THIS_MODULE);
1191         ret = _request_firmware(firmware_p, name, device, FW_OPT_UEVENT);
1192         module_put(THIS_MODULE);
1193         return ret;
1194 }
1195 EXPORT_SYMBOL_GPL(request_firmware_direct);
1196 #endif
1197
1198 /**
1199  * release_firmware: - release the resource associated with a firmware image
1200  * @fw: firmware resource to release
1201  **/
1202 void release_firmware(const struct firmware *fw)
1203 {
1204         if (fw) {
1205                 if (!fw_is_builtin_firmware(fw))
1206                         firmware_free_data(fw);
1207                 kfree(fw);
1208         }
1209 }
1210 EXPORT_SYMBOL(release_firmware);
1211
1212 /* Async support */
1213 struct firmware_work {
1214         struct work_struct work;
1215         struct module *module;
1216         const char *name;
1217         struct device *device;
1218         void *context;
1219         void (*cont)(const struct firmware *fw, void *context);
1220         unsigned int opt_flags;
1221 };
1222
1223 static void request_firmware_work_func(struct work_struct *work)
1224 {
1225         struct firmware_work *fw_work;
1226         const struct firmware *fw;
1227
1228         fw_work = container_of(work, struct firmware_work, work);
1229
1230         _request_firmware(&fw, fw_work->name, fw_work->device,
1231                           fw_work->opt_flags);
1232         fw_work->cont(fw, fw_work->context);
1233         put_device(fw_work->device); /* taken in request_firmware_nowait() */
1234
1235         module_put(fw_work->module);
1236         kfree(fw_work);
1237 }
1238
1239 /**
1240  * request_firmware_nowait - asynchronous version of request_firmware
1241  * @module: module requesting the firmware
1242  * @uevent: sends uevent to copy the firmware image if this flag
1243  *      is non-zero else the firmware copy must be done manually.
1244  * @name: name of firmware file
1245  * @device: device for which firmware is being loaded
1246  * @gfp: allocation flags
1247  * @context: will be passed over to @cont, and
1248  *      @fw may be %NULL if firmware request fails.
1249  * @cont: function will be called asynchronously when the firmware
1250  *      request is over.
1251  *
1252  *      Caller must hold the reference count of @device.
1253  *
1254  *      Asynchronous variant of request_firmware() for user contexts:
1255  *              - sleep for as small periods as possible since it may
1256  *              increase kernel boot time of built-in device drivers
1257  *              requesting firmware in their ->probe() methods, if
1258  *              @gfp is GFP_KERNEL.
1259  *
1260  *              - can't sleep at all if @gfp is GFP_ATOMIC.
1261  **/
1262 int
1263 request_firmware_nowait(
1264         struct module *module, bool uevent,
1265         const char *name, struct device *device, gfp_t gfp, void *context,
1266         void (*cont)(const struct firmware *fw, void *context))
1267 {
1268         struct firmware_work *fw_work;
1269
1270         fw_work = kzalloc(sizeof (struct firmware_work), gfp);
1271         if (!fw_work)
1272                 return -ENOMEM;
1273
1274         fw_work->module = module;
1275         fw_work->name = name;
1276         fw_work->device = device;
1277         fw_work->context = context;
1278         fw_work->cont = cont;
1279         fw_work->opt_flags = FW_OPT_NOWAIT | FW_OPT_FALLBACK |
1280                 (uevent ? FW_OPT_UEVENT : 0);
1281
1282         if (!try_module_get(module)) {
1283                 kfree(fw_work);
1284                 return -EFAULT;
1285         }
1286
1287         get_device(fw_work->device);
1288         INIT_WORK(&fw_work->work, request_firmware_work_func);
1289         schedule_work(&fw_work->work);
1290         return 0;
1291 }
1292 EXPORT_SYMBOL(request_firmware_nowait);
1293
1294 #ifdef CONFIG_PM_SLEEP
1295 static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
1296
1297 /**
1298  * cache_firmware - cache one firmware image in kernel memory space
1299  * @fw_name: the firmware image name
1300  *
1301  * Cache firmware in kernel memory so that drivers can use it when
1302  * system isn't ready for them to request firmware image from userspace.
1303  * Once it returns successfully, driver can use request_firmware or its
1304  * nowait version to get the cached firmware without any interacting
1305  * with userspace
1306  *
1307  * Return 0 if the firmware image has been cached successfully
1308  * Return !0 otherwise
1309  *
1310  */
1311 static int cache_firmware(const char *fw_name)
1312 {
1313         int ret;
1314         const struct firmware *fw;
1315
1316         pr_debug("%s: %s\n", __func__, fw_name);
1317
1318         ret = request_firmware(&fw, fw_name, NULL);
1319         if (!ret)
1320                 kfree(fw);
1321
1322         pr_debug("%s: %s ret=%d\n", __func__, fw_name, ret);
1323
1324         return ret;
1325 }
1326
1327 static struct firmware_buf *fw_lookup_buf(const char *fw_name)
1328 {
1329         struct firmware_buf *tmp;
1330         struct firmware_cache *fwc = &fw_cache;
1331
1332         spin_lock(&fwc->lock);
1333         tmp = __fw_lookup_buf(fw_name);
1334         spin_unlock(&fwc->lock);
1335
1336         return tmp;
1337 }
1338
1339 /**
1340  * uncache_firmware - remove one cached firmware image
1341  * @fw_name: the firmware image name
1342  *
1343  * Uncache one firmware image which has been cached successfully
1344  * before.
1345  *
1346  * Return 0 if the firmware cache has been removed successfully
1347  * Return !0 otherwise
1348  *
1349  */
1350 static int uncache_firmware(const char *fw_name)
1351 {
1352         struct firmware_buf *buf;
1353         struct firmware fw;
1354
1355         pr_debug("%s: %s\n", __func__, fw_name);
1356
1357         if (fw_get_builtin_firmware(&fw, fw_name))
1358                 return 0;
1359
1360         buf = fw_lookup_buf(fw_name);
1361         if (buf) {
1362                 fw_free_buf(buf);
1363                 return 0;
1364         }
1365
1366         return -EINVAL;
1367 }
1368
1369 static struct fw_cache_entry *alloc_fw_cache_entry(const char *name)
1370 {
1371         struct fw_cache_entry *fce;
1372
1373         fce = kzalloc(sizeof(*fce) + strlen(name) + 1, GFP_ATOMIC);
1374         if (!fce)
1375                 goto exit;
1376
1377         strcpy(fce->name, name);
1378 exit:
1379         return fce;
1380 }
1381
1382 static int __fw_entry_found(const char *name)
1383 {
1384         struct firmware_cache *fwc = &fw_cache;
1385         struct fw_cache_entry *fce;
1386
1387         list_for_each_entry(fce, &fwc->fw_names, list) {
1388                 if (!strcmp(fce->name, name))
1389                         return 1;
1390         }
1391         return 0;
1392 }
1393
1394 static int fw_cache_piggyback_on_request(const char *name)
1395 {
1396         struct firmware_cache *fwc = &fw_cache;
1397         struct fw_cache_entry *fce;
1398         int ret = 0;
1399
1400         spin_lock(&fwc->name_lock);
1401         if (__fw_entry_found(name))
1402                 goto found;
1403
1404         fce = alloc_fw_cache_entry(name);
1405         if (fce) {
1406                 ret = 1;
1407                 list_add(&fce->list, &fwc->fw_names);
1408                 pr_debug("%s: fw: %s\n", __func__, name);
1409         }
1410 found:
1411         spin_unlock(&fwc->name_lock);
1412         return ret;
1413 }
1414
1415 static void free_fw_cache_entry(struct fw_cache_entry *fce)
1416 {
1417         kfree(fce);
1418 }
1419
1420 static void __async_dev_cache_fw_image(void *fw_entry,
1421                                        async_cookie_t cookie)
1422 {
1423         struct fw_cache_entry *fce = fw_entry;
1424         struct firmware_cache *fwc = &fw_cache;
1425         int ret;
1426
1427         ret = cache_firmware(fce->name);
1428         if (ret) {
1429                 spin_lock(&fwc->name_lock);
1430                 list_del(&fce->list);
1431                 spin_unlock(&fwc->name_lock);
1432
1433                 free_fw_cache_entry(fce);
1434         }
1435 }
1436
1437 /* called with dev->devres_lock held */
1438 static void dev_create_fw_entry(struct device *dev, void *res,
1439                                 void *data)
1440 {
1441         struct fw_name_devm *fwn = res;
1442         const char *fw_name = fwn->name;
1443         struct list_head *head = data;
1444         struct fw_cache_entry *fce;
1445
1446         fce = alloc_fw_cache_entry(fw_name);
1447         if (fce)
1448                 list_add(&fce->list, head);
1449 }
1450
1451 static int devm_name_match(struct device *dev, void *res,
1452                            void *match_data)
1453 {
1454         struct fw_name_devm *fwn = res;
1455         return (fwn->magic == (unsigned long)match_data);
1456 }
1457
1458 static void dev_cache_fw_image(struct device *dev, void *data)
1459 {
1460         LIST_HEAD(todo);
1461         struct fw_cache_entry *fce;
1462         struct fw_cache_entry *fce_next;
1463         struct firmware_cache *fwc = &fw_cache;
1464
1465         devres_for_each_res(dev, fw_name_devm_release,
1466                             devm_name_match, &fw_cache,
1467                             dev_create_fw_entry, &todo);
1468
1469         list_for_each_entry_safe(fce, fce_next, &todo, list) {
1470                 list_del(&fce->list);
1471
1472                 spin_lock(&fwc->name_lock);
1473                 /* only one cache entry for one firmware */
1474                 if (!__fw_entry_found(fce->name)) {
1475                         list_add(&fce->list, &fwc->fw_names);
1476                 } else {
1477                         free_fw_cache_entry(fce);
1478                         fce = NULL;
1479                 }
1480                 spin_unlock(&fwc->name_lock);
1481
1482                 if (fce)
1483                         async_schedule_domain(__async_dev_cache_fw_image,
1484                                               (void *)fce,
1485                                               &fw_cache_domain);
1486         }
1487 }
1488
1489 static void __device_uncache_fw_images(void)
1490 {
1491         struct firmware_cache *fwc = &fw_cache;
1492         struct fw_cache_entry *fce;
1493
1494         spin_lock(&fwc->name_lock);
1495         while (!list_empty(&fwc->fw_names)) {
1496                 fce = list_entry(fwc->fw_names.next,
1497                                 struct fw_cache_entry, list);
1498                 list_del(&fce->list);
1499                 spin_unlock(&fwc->name_lock);
1500
1501                 uncache_firmware(fce->name);
1502                 free_fw_cache_entry(fce);
1503
1504                 spin_lock(&fwc->name_lock);
1505         }
1506         spin_unlock(&fwc->name_lock);
1507 }
1508
1509 /**
1510  * device_cache_fw_images - cache devices' firmware
1511  *
1512  * If one device called request_firmware or its nowait version
1513  * successfully before, the firmware names are recored into the
1514  * device's devres link list, so device_cache_fw_images can call
1515  * cache_firmware() to cache these firmwares for the device,
1516  * then the device driver can load its firmwares easily at
1517  * time when system is not ready to complete loading firmware.
1518  */
1519 static void device_cache_fw_images(void)
1520 {
1521         struct firmware_cache *fwc = &fw_cache;
1522         int old_timeout;
1523         DEFINE_WAIT(wait);
1524
1525         pr_debug("%s\n", __func__);
1526
1527         /* cancel uncache work */
1528         cancel_delayed_work_sync(&fwc->work);
1529
1530         /*
1531          * use small loading timeout for caching devices' firmware
1532          * because all these firmware images have been loaded
1533          * successfully at lease once, also system is ready for
1534          * completing firmware loading now. The maximum size of
1535          * firmware in current distributions is about 2M bytes,
1536          * so 10 secs should be enough.
1537          */
1538         old_timeout = loading_timeout;
1539         loading_timeout = 10;
1540
1541         mutex_lock(&fw_lock);
1542         fwc->state = FW_LOADER_START_CACHE;
1543         dpm_for_each_dev(NULL, dev_cache_fw_image);
1544         mutex_unlock(&fw_lock);
1545
1546         /* wait for completion of caching firmware for all devices */
1547         async_synchronize_full_domain(&fw_cache_domain);
1548
1549         loading_timeout = old_timeout;
1550 }
1551
1552 /**
1553  * device_uncache_fw_images - uncache devices' firmware
1554  *
1555  * uncache all firmwares which have been cached successfully
1556  * by device_uncache_fw_images earlier
1557  */
1558 static void device_uncache_fw_images(void)
1559 {
1560         pr_debug("%s\n", __func__);
1561         __device_uncache_fw_images();
1562 }
1563
1564 static void device_uncache_fw_images_work(struct work_struct *work)
1565 {
1566         device_uncache_fw_images();
1567 }
1568
1569 /**
1570  * device_uncache_fw_images_delay - uncache devices firmwares
1571  * @delay: number of milliseconds to delay uncache device firmwares
1572  *
1573  * uncache all devices's firmwares which has been cached successfully
1574  * by device_cache_fw_images after @delay milliseconds.
1575  */
1576 static void device_uncache_fw_images_delay(unsigned long delay)
1577 {
1578         queue_delayed_work(system_power_efficient_wq, &fw_cache.work,
1579                            msecs_to_jiffies(delay));
1580 }
1581
1582 static int fw_pm_notify(struct notifier_block *notify_block,
1583                         unsigned long mode, void *unused)
1584 {
1585         switch (mode) {
1586         case PM_HIBERNATION_PREPARE:
1587         case PM_SUSPEND_PREPARE:
1588         case PM_RESTORE_PREPARE:
1589                 kill_requests_without_uevent();
1590                 device_cache_fw_images();
1591                 break;
1592
1593         case PM_POST_SUSPEND:
1594         case PM_POST_HIBERNATION:
1595         case PM_POST_RESTORE:
1596                 /*
1597                  * In case that system sleep failed and syscore_suspend is
1598                  * not called.
1599                  */
1600                 mutex_lock(&fw_lock);
1601                 fw_cache.state = FW_LOADER_NO_CACHE;
1602                 mutex_unlock(&fw_lock);
1603
1604                 device_uncache_fw_images_delay(10 * MSEC_PER_SEC);
1605                 break;
1606         }
1607
1608         return 0;
1609 }
1610
1611 /* stop caching firmware once syscore_suspend is reached */
1612 static int fw_suspend(void)
1613 {
1614         fw_cache.state = FW_LOADER_NO_CACHE;
1615         return 0;
1616 }
1617
1618 static struct syscore_ops fw_syscore_ops = {
1619         .suspend = fw_suspend,
1620 };
1621 #else
1622 static int fw_cache_piggyback_on_request(const char *name)
1623 {
1624         return 0;
1625 }
1626 #endif
1627
1628 static void __init fw_cache_init(void)
1629 {
1630         spin_lock_init(&fw_cache.lock);
1631         INIT_LIST_HEAD(&fw_cache.head);
1632         fw_cache.state = FW_LOADER_NO_CACHE;
1633
1634 #ifdef CONFIG_PM_SLEEP
1635         spin_lock_init(&fw_cache.name_lock);
1636         INIT_LIST_HEAD(&fw_cache.fw_names);
1637
1638         INIT_DELAYED_WORK(&fw_cache.work,
1639                           device_uncache_fw_images_work);
1640
1641         fw_cache.pm_notify.notifier_call = fw_pm_notify;
1642         register_pm_notifier(&fw_cache.pm_notify);
1643
1644         register_syscore_ops(&fw_syscore_ops);
1645 #endif
1646 }
1647
1648 static int __init firmware_class_init(void)
1649 {
1650         fw_cache_init();
1651 #ifdef CONFIG_FW_LOADER_USER_HELPER
1652         register_reboot_notifier(&fw_shutdown_nb);
1653         return class_register(&firmware_class);
1654 #else
1655         return 0;
1656 #endif
1657 }
1658
1659 static void __exit firmware_class_exit(void)
1660 {
1661 #ifdef CONFIG_PM_SLEEP
1662         unregister_syscore_ops(&fw_syscore_ops);
1663         unregister_pm_notifier(&fw_cache.pm_notify);
1664 #endif
1665 #ifdef CONFIG_FW_LOADER_USER_HELPER
1666         unregister_reboot_notifier(&fw_shutdown_nb);
1667         class_unregister(&firmware_class);
1668 #endif
1669 }
1670
1671 fs_initcall(firmware_class_init);
1672 module_exit(firmware_class_exit);