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