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   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
  36MODULE_AUTHOR("Manuel Estrada Sainz");
  37MODULE_DESCRIPTION("Multi purpose firmware loading support");
  38MODULE_LICENSE("GPL");
  39
  40/* Builtin firmware support */
  41
  42#ifdef CONFIG_FW_LOADER
  43
  44extern struct builtin_fw __start_builtin_fw[];
  45extern struct builtin_fw __end_builtin_fw[];
  46
  47static 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
  62static 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
  75static inline bool fw_get_builtin_firmware(struct firmware *fw, const char *name)
  76{
  77	return false;
  78}
  79
  80static inline bool fw_is_builtin_firmware(const struct firmware *fw)
  81{
  82	return false;
  83}
  84#endif
  85
  86enum {
  87	FW_STATUS_LOADING,
  88	FW_STATUS_DONE,
  89	FW_STATUS_ABORT,
  90};
  91
  92static int loading_timeout = 60;	/* In seconds */
  93
  94static 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
 108struct 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
 130struct 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
 149struct fw_cache_entry {
 150	struct list_head list;
 151	char name[];
 152};
 153
 154struct 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
 164static 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 */
 168static DEFINE_MUTEX(fw_lock);
 169
 170static struct firmware_cache fw_cache;
 171
 172static 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
 195static 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
 206static 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
 230static 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
 256static 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 */
 265static char fw_path_para[256];
 266static 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 */
 279module_param_string(path, fw_path_para, sizeof(fw_path_para), 0644);
 280MODULE_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 */
 283static 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
 295static 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
 319static 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 */
 361static 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 */
 372static 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
 387static 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
 396static 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
 405static 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 */
 416static 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
 436static 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
 447struct 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
 455static struct firmware_priv *to_firmware_priv(struct device *dev)
 456{
 457	return container_of(dev, struct firmware_priv, dev);
 458}
 459
 460static 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
 474static 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
 487static LIST_HEAD(pending_fw_head);
 488
 489/* reboot notifier for avoid deadlock with usermode_lock */
 490static 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
 502static struct notifier_block fw_shutdown_nb = {
 503	.notifier_call = fw_shutdown_notify,
 504};
 505
 506static 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 **/
 525static 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
 535static struct class_attribute firmware_class_attrs[] = {
 536	__ATTR_RW(timeout),
 537	__ATTR_NULL
 538};
 539
 540static 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
 547static 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
 561static 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
 568static 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 */
 588static 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 **/
 614static 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	}
 667out:
 668	mutex_unlock(&fw_lock);
 669	return count;
 670}
 671
 672static DEVICE_ATTR(loading, 0644, firmware_loading_show, firmware_loading_store);
 673
 674static 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	}
 713out:
 714	mutex_unlock(&fw_lock);
 715	return ret_count;
 716}
 717
 718static 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 **/
 769static 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);
 811out:
 812	mutex_unlock(&fw_lock);
 813	return retval;
 814}
 815
 816static 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
 823static 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
 833static struct firmware_priv *
 834fw_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;
 858exit:
 859	return fw_priv;
 860}
 861
 862/* load a firmware via user helper */
 863static 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);
 918err_del_bin_attr:
 919	device_remove_bin_file(f_dev, &firmware_attr_data);
 920err_del_dev:
 921	device_del(f_dev);
 922err_put_dev:
 923	put_device(f_dev);
 924	return retval;
 925}
 926
 927static 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 */
 943static 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 */
 958static inline int
 959fw_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
 970static 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) */
 977static 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 */
 999static 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
1040static 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() */
1078static 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 **/
1159int
1160request_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}
1172EXPORT_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 **/
1186int 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}
1195EXPORT_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 **/
1202void 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}
1210EXPORT_SYMBOL(release_firmware);
1211
1212/* Async support */
1213struct 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
1223static 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 **/
1262int
1263request_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}
1292EXPORT_SYMBOL(request_firmware_nowait);
1293
1294#ifdef CONFIG_PM_SLEEP
1295static 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 */
1311static 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
1327static 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 */
1350static 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
1369static 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);
1378exit:
1379	return fce;
1380}
1381
1382static 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
1394static 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	}
1410found:
1411	spin_unlock(&fwc->name_lock);
1412	return ret;
1413}
1414
1415static void free_fw_cache_entry(struct fw_cache_entry *fce)
1416{
1417	kfree(fce);
1418}
1419
1420static 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 */
1438static 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
1451static 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
1458static 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
1489static 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 */
1519static 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 */
1558static void device_uncache_fw_images(void)
1559{
1560	pr_debug("%s\n", __func__);
1561	__device_uncache_fw_images();
1562}
1563
1564static 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 */
1576static 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
1582static 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 */
1612static int fw_suspend(void)
1613{
1614	fw_cache.state = FW_LOADER_NO_CACHE;
1615	return 0;
1616}
1617
1618static struct syscore_ops fw_syscore_ops = {
1619	.suspend = fw_suspend,
1620};
1621#else
1622static int fw_cache_piggyback_on_request(const char *name)
1623{
1624	return 0;
1625}
1626#endif
1627
1628static 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
1648static 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
1659static 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
1671fs_initcall(firmware_class_init);
1672module_exit(firmware_class_exit);