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   1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * main.c - Multi purpose firmware loading support
   4 *
   5 * Copyright (c) 2003 Manuel Estrada Sainz
   6 *
   7 * Please see Documentation/driver-api/firmware/ for more information.
   8 *
   9 */
  10
  11#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  12
  13#include <linux/capability.h>
  14#include <linux/device.h>
  15#include <linux/kernel_read_file.h>
  16#include <linux/module.h>
  17#include <linux/init.h>
  18#include <linux/initrd.h>
  19#include <linux/timer.h>
  20#include <linux/vmalloc.h>
  21#include <linux/interrupt.h>
  22#include <linux/bitops.h>
  23#include <linux/mutex.h>
  24#include <linux/workqueue.h>
  25#include <linux/highmem.h>
  26#include <linux/firmware.h>
  27#include <linux/slab.h>
  28#include <linux/sched.h>
  29#include <linux/file.h>
  30#include <linux/list.h>
  31#include <linux/fs.h>
  32#include <linux/async.h>
  33#include <linux/pm.h>
  34#include <linux/suspend.h>
  35#include <linux/syscore_ops.h>
  36#include <linux/reboot.h>
  37#include <linux/security.h>
  38#include <linux/xz.h>
  39
  40#include <generated/utsrelease.h>
  41
  42#include "../base.h"
  43#include "firmware.h"
  44#include "fallback.h"
  45
  46MODULE_AUTHOR("Manuel Estrada Sainz");
  47MODULE_DESCRIPTION("Multi purpose firmware loading support");
  48MODULE_LICENSE("GPL");
  49
  50struct firmware_cache {
  51	/* firmware_buf instance will be added into the below list */
  52	spinlock_t lock;
  53	struct list_head head;
  54	int state;
  55
  56#ifdef CONFIG_FW_CACHE
  57	/*
  58	 * Names of firmware images which have been cached successfully
  59	 * will be added into the below list so that device uncache
  60	 * helper can trace which firmware images have been cached
  61	 * before.
  62	 */
  63	spinlock_t name_lock;
  64	struct list_head fw_names;
  65
  66	struct delayed_work work;
  67
  68	struct notifier_block   pm_notify;
  69#endif
  70};
  71
  72struct fw_cache_entry {
  73	struct list_head list;
  74	const char *name;
  75};
  76
  77struct fw_name_devm {
  78	unsigned long magic;
  79	const char *name;
  80};
  81
  82static inline struct fw_priv *to_fw_priv(struct kref *ref)
  83{
  84	return container_of(ref, struct fw_priv, ref);
  85}
  86
  87#define	FW_LOADER_NO_CACHE	0
  88#define	FW_LOADER_START_CACHE	1
  89
  90/* fw_lock could be moved to 'struct fw_sysfs' but since it is just
  91 * guarding for corner cases a global lock should be OK */
  92DEFINE_MUTEX(fw_lock);
  93
  94static struct firmware_cache fw_cache;
  95
  96/* Builtin firmware support */
  97
  98#ifdef CONFIG_FW_LOADER
  99
 100extern struct builtin_fw __start_builtin_fw[];
 101extern struct builtin_fw __end_builtin_fw[];
 102
 103static void fw_copy_to_prealloc_buf(struct firmware *fw,
 104				    void *buf, size_t size)
 105{
 106	if (!buf || size < fw->size)
 107		return;
 108	memcpy(buf, fw->data, fw->size);
 109}
 110
 111static bool fw_get_builtin_firmware(struct firmware *fw, const char *name,
 112				    void *buf, size_t size)
 113{
 114	struct builtin_fw *b_fw;
 115
 116	for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++) {
 117		if (strcmp(name, b_fw->name) == 0) {
 118			fw->size = b_fw->size;
 119			fw->data = b_fw->data;
 120			fw_copy_to_prealloc_buf(fw, buf, size);
 121
 122			return true;
 123		}
 124	}
 125
 126	return false;
 127}
 128
 129static bool fw_is_builtin_firmware(const struct firmware *fw)
 130{
 131	struct builtin_fw *b_fw;
 132
 133	for (b_fw = __start_builtin_fw; b_fw != __end_builtin_fw; b_fw++)
 134		if (fw->data == b_fw->data)
 135			return true;
 136
 137	return false;
 138}
 139
 140#else /* Module case - no builtin firmware support */
 141
 142static inline bool fw_get_builtin_firmware(struct firmware *fw,
 143					   const char *name, void *buf,
 144					   size_t size)
 145{
 146	return false;
 147}
 148
 149static inline bool fw_is_builtin_firmware(const struct firmware *fw)
 150{
 151	return false;
 152}
 153#endif
 154
 155static void fw_state_init(struct fw_priv *fw_priv)
 156{
 157	struct fw_state *fw_st = &fw_priv->fw_st;
 158
 159	init_completion(&fw_st->completion);
 160	fw_st->status = FW_STATUS_UNKNOWN;
 161}
 162
 163static inline int fw_state_wait(struct fw_priv *fw_priv)
 164{
 165	return __fw_state_wait_common(fw_priv, MAX_SCHEDULE_TIMEOUT);
 166}
 167
 168static void fw_cache_piggyback_on_request(struct fw_priv *fw_priv);
 169
 170static struct fw_priv *__allocate_fw_priv(const char *fw_name,
 171					  struct firmware_cache *fwc,
 172					  void *dbuf,
 173					  size_t size,
 174					  size_t offset,
 175					  u32 opt_flags)
 176{
 177	struct fw_priv *fw_priv;
 178
 179	/* For a partial read, the buffer must be preallocated. */
 180	if ((opt_flags & FW_OPT_PARTIAL) && !dbuf)
 181		return NULL;
 182
 183	/* Only partial reads are allowed to use an offset. */
 184	if (offset != 0 && !(opt_flags & FW_OPT_PARTIAL))
 185		return NULL;
 186
 187	fw_priv = kzalloc(sizeof(*fw_priv), GFP_ATOMIC);
 188	if (!fw_priv)
 189		return NULL;
 190
 191	fw_priv->fw_name = kstrdup_const(fw_name, GFP_ATOMIC);
 192	if (!fw_priv->fw_name) {
 193		kfree(fw_priv);
 194		return NULL;
 195	}
 196
 197	kref_init(&fw_priv->ref);
 198	fw_priv->fwc = fwc;
 199	fw_priv->data = dbuf;
 200	fw_priv->allocated_size = size;
 201	fw_priv->offset = offset;
 202	fw_priv->opt_flags = opt_flags;
 203	fw_state_init(fw_priv);
 204#ifdef CONFIG_FW_LOADER_USER_HELPER
 205	INIT_LIST_HEAD(&fw_priv->pending_list);
 206#endif
 207
 208	pr_debug("%s: fw-%s fw_priv=%p\n", __func__, fw_name, fw_priv);
 209
 210	return fw_priv;
 211}
 212
 213static struct fw_priv *__lookup_fw_priv(const char *fw_name)
 214{
 215	struct fw_priv *tmp;
 216	struct firmware_cache *fwc = &fw_cache;
 217
 218	list_for_each_entry(tmp, &fwc->head, list)
 219		if (!strcmp(tmp->fw_name, fw_name))
 220			return tmp;
 221	return NULL;
 222}
 223
 224/* Returns 1 for batching firmware requests with the same name */
 225static int alloc_lookup_fw_priv(const char *fw_name,
 226				struct firmware_cache *fwc,
 227				struct fw_priv **fw_priv,
 228				void *dbuf,
 229				size_t size,
 230				size_t offset,
 231				u32 opt_flags)
 232{
 233	struct fw_priv *tmp;
 234
 235	spin_lock(&fwc->lock);
 236	/*
 237	 * Do not merge requests that are marked to be non-cached or
 238	 * are performing partial reads.
 239	 */
 240	if (!(opt_flags & (FW_OPT_NOCACHE | FW_OPT_PARTIAL))) {
 241		tmp = __lookup_fw_priv(fw_name);
 242		if (tmp) {
 243			kref_get(&tmp->ref);
 244			spin_unlock(&fwc->lock);
 245			*fw_priv = tmp;
 246			pr_debug("batched request - sharing the same struct fw_priv and lookup for multiple requests\n");
 247			return 1;
 248		}
 249	}
 250
 251	tmp = __allocate_fw_priv(fw_name, fwc, dbuf, size, offset, opt_flags);
 252	if (tmp) {
 253		INIT_LIST_HEAD(&tmp->list);
 254		if (!(opt_flags & FW_OPT_NOCACHE))
 255			list_add(&tmp->list, &fwc->head);
 256	}
 257	spin_unlock(&fwc->lock);
 258
 259	*fw_priv = tmp;
 260
 261	return tmp ? 0 : -ENOMEM;
 262}
 263
 264static void __free_fw_priv(struct kref *ref)
 265	__releases(&fwc->lock)
 266{
 267	struct fw_priv *fw_priv = to_fw_priv(ref);
 268	struct firmware_cache *fwc = fw_priv->fwc;
 269
 270	pr_debug("%s: fw-%s fw_priv=%p data=%p size=%u\n",
 271		 __func__, fw_priv->fw_name, fw_priv, fw_priv->data,
 272		 (unsigned int)fw_priv->size);
 273
 274	list_del(&fw_priv->list);
 275	spin_unlock(&fwc->lock);
 276
 277	if (fw_is_paged_buf(fw_priv))
 278		fw_free_paged_buf(fw_priv);
 279	else if (!fw_priv->allocated_size)
 280		vfree(fw_priv->data);
 281
 282	kfree_const(fw_priv->fw_name);
 283	kfree(fw_priv);
 284}
 285
 286static void free_fw_priv(struct fw_priv *fw_priv)
 287{
 288	struct firmware_cache *fwc = fw_priv->fwc;
 289	spin_lock(&fwc->lock);
 290	if (!kref_put(&fw_priv->ref, __free_fw_priv))
 291		spin_unlock(&fwc->lock);
 292}
 293
 294#ifdef CONFIG_FW_LOADER_PAGED_BUF
 295bool fw_is_paged_buf(struct fw_priv *fw_priv)
 296{
 297	return fw_priv->is_paged_buf;
 298}
 299
 300void fw_free_paged_buf(struct fw_priv *fw_priv)
 301{
 302	int i;
 303
 304	if (!fw_priv->pages)
 305		return;
 306
 307	vunmap(fw_priv->data);
 308
 309	for (i = 0; i < fw_priv->nr_pages; i++)
 310		__free_page(fw_priv->pages[i]);
 311	kvfree(fw_priv->pages);
 312	fw_priv->pages = NULL;
 313	fw_priv->page_array_size = 0;
 314	fw_priv->nr_pages = 0;
 315}
 316
 317int fw_grow_paged_buf(struct fw_priv *fw_priv, int pages_needed)
 318{
 319	/* If the array of pages is too small, grow it */
 320	if (fw_priv->page_array_size < pages_needed) {
 321		int new_array_size = max(pages_needed,
 322					 fw_priv->page_array_size * 2);
 323		struct page **new_pages;
 324
 325		new_pages = kvmalloc_array(new_array_size, sizeof(void *),
 326					   GFP_KERNEL);
 327		if (!new_pages)
 328			return -ENOMEM;
 329		memcpy(new_pages, fw_priv->pages,
 330		       fw_priv->page_array_size * sizeof(void *));
 331		memset(&new_pages[fw_priv->page_array_size], 0, sizeof(void *) *
 332		       (new_array_size - fw_priv->page_array_size));
 333		kvfree(fw_priv->pages);
 334		fw_priv->pages = new_pages;
 335		fw_priv->page_array_size = new_array_size;
 336	}
 337
 338	while (fw_priv->nr_pages < pages_needed) {
 339		fw_priv->pages[fw_priv->nr_pages] =
 340			alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
 341
 342		if (!fw_priv->pages[fw_priv->nr_pages])
 343			return -ENOMEM;
 344		fw_priv->nr_pages++;
 345	}
 346
 347	return 0;
 348}
 349
 350int fw_map_paged_buf(struct fw_priv *fw_priv)
 351{
 352	/* one pages buffer should be mapped/unmapped only once */
 353	if (!fw_priv->pages)
 354		return 0;
 355
 356	vunmap(fw_priv->data);
 357	fw_priv->data = vmap(fw_priv->pages, fw_priv->nr_pages, 0,
 358			     PAGE_KERNEL_RO);
 359	if (!fw_priv->data)
 360		return -ENOMEM;
 361
 362	return 0;
 363}
 364#endif
 365
 366/*
 367 * XZ-compressed firmware support
 368 */
 369#ifdef CONFIG_FW_LOADER_COMPRESS
 370/* show an error and return the standard error code */
 371static int fw_decompress_xz_error(struct device *dev, enum xz_ret xz_ret)
 372{
 373	if (xz_ret != XZ_STREAM_END) {
 374		dev_warn(dev, "xz decompression failed (xz_ret=%d)\n", xz_ret);
 375		return xz_ret == XZ_MEM_ERROR ? -ENOMEM : -EINVAL;
 376	}
 377	return 0;
 378}
 379
 380/* single-shot decompression onto the pre-allocated buffer */
 381static int fw_decompress_xz_single(struct device *dev, struct fw_priv *fw_priv,
 382				   size_t in_size, const void *in_buffer)
 383{
 384	struct xz_dec *xz_dec;
 385	struct xz_buf xz_buf;
 386	enum xz_ret xz_ret;
 387
 388	xz_dec = xz_dec_init(XZ_SINGLE, (u32)-1);
 389	if (!xz_dec)
 390		return -ENOMEM;
 391
 392	xz_buf.in_size = in_size;
 393	xz_buf.in = in_buffer;
 394	xz_buf.in_pos = 0;
 395	xz_buf.out_size = fw_priv->allocated_size;
 396	xz_buf.out = fw_priv->data;
 397	xz_buf.out_pos = 0;
 398
 399	xz_ret = xz_dec_run(xz_dec, &xz_buf);
 400	xz_dec_end(xz_dec);
 401
 402	fw_priv->size = xz_buf.out_pos;
 403	return fw_decompress_xz_error(dev, xz_ret);
 404}
 405
 406/* decompression on paged buffer and map it */
 407static int fw_decompress_xz_pages(struct device *dev, struct fw_priv *fw_priv,
 408				  size_t in_size, const void *in_buffer)
 409{
 410	struct xz_dec *xz_dec;
 411	struct xz_buf xz_buf;
 412	enum xz_ret xz_ret;
 413	struct page *page;
 414	int err = 0;
 415
 416	xz_dec = xz_dec_init(XZ_DYNALLOC, (u32)-1);
 417	if (!xz_dec)
 418		return -ENOMEM;
 419
 420	xz_buf.in_size = in_size;
 421	xz_buf.in = in_buffer;
 422	xz_buf.in_pos = 0;
 423
 424	fw_priv->is_paged_buf = true;
 425	fw_priv->size = 0;
 426	do {
 427		if (fw_grow_paged_buf(fw_priv, fw_priv->nr_pages + 1)) {
 428			err = -ENOMEM;
 429			goto out;
 430		}
 431
 432		/* decompress onto the new allocated page */
 433		page = fw_priv->pages[fw_priv->nr_pages - 1];
 434		xz_buf.out = kmap(page);
 435		xz_buf.out_pos = 0;
 436		xz_buf.out_size = PAGE_SIZE;
 437		xz_ret = xz_dec_run(xz_dec, &xz_buf);
 438		kunmap(page);
 439		fw_priv->size += xz_buf.out_pos;
 440		/* partial decompression means either end or error */
 441		if (xz_buf.out_pos != PAGE_SIZE)
 442			break;
 443	} while (xz_ret == XZ_OK);
 444
 445	err = fw_decompress_xz_error(dev, xz_ret);
 446	if (!err)
 447		err = fw_map_paged_buf(fw_priv);
 448
 449 out:
 450	xz_dec_end(xz_dec);
 451	return err;
 452}
 453
 454static int fw_decompress_xz(struct device *dev, struct fw_priv *fw_priv,
 455			    size_t in_size, const void *in_buffer)
 456{
 457	/* if the buffer is pre-allocated, we can perform in single-shot mode */
 458	if (fw_priv->data)
 459		return fw_decompress_xz_single(dev, fw_priv, in_size, in_buffer);
 460	else
 461		return fw_decompress_xz_pages(dev, fw_priv, in_size, in_buffer);
 462}
 463#endif /* CONFIG_FW_LOADER_COMPRESS */
 464
 465/* direct firmware loading support */
 466static char fw_path_para[256];
 467static const char * const fw_path[] = {
 468	fw_path_para,
 469	"/lib/firmware/updates/" UTS_RELEASE,
 470	"/lib/firmware/updates",
 471	"/lib/firmware/" UTS_RELEASE,
 472	"/lib/firmware"
 473};
 474
 475/*
 476 * Typical usage is that passing 'firmware_class.path=$CUSTOMIZED_PATH'
 477 * from kernel command line because firmware_class is generally built in
 478 * kernel instead of module.
 479 */
 480module_param_string(path, fw_path_para, sizeof(fw_path_para), 0644);
 481MODULE_PARM_DESC(path, "customized firmware image search path with a higher priority than default path");
 482
 483static int
 484fw_get_filesystem_firmware(struct device *device, struct fw_priv *fw_priv,
 485			   const char *suffix,
 486			   int (*decompress)(struct device *dev,
 487					     struct fw_priv *fw_priv,
 488					     size_t in_size,
 489					     const void *in_buffer))
 490{
 491	size_t size;
 492	int i, len;
 493	int rc = -ENOENT;
 494	char *path;
 495	size_t msize = INT_MAX;
 496	void *buffer = NULL;
 497
 498	/* Already populated data member means we're loading into a buffer */
 499	if (!decompress && fw_priv->data) {
 500		buffer = fw_priv->data;
 501		msize = fw_priv->allocated_size;
 502	}
 503
 504	path = __getname();
 505	if (!path)
 506		return -ENOMEM;
 507
 508	wait_for_initramfs();
 509	for (i = 0; i < ARRAY_SIZE(fw_path); i++) {
 510		size_t file_size = 0;
 511		size_t *file_size_ptr = NULL;
 512
 513		/* skip the unset customized path */
 514		if (!fw_path[i][0])
 515			continue;
 516
 517		len = snprintf(path, PATH_MAX, "%s/%s%s",
 518			       fw_path[i], fw_priv->fw_name, suffix);
 519		if (len >= PATH_MAX) {
 520			rc = -ENAMETOOLONG;
 521			break;
 522		}
 523
 524		fw_priv->size = 0;
 525
 526		/*
 527		 * The total file size is only examined when doing a partial
 528		 * read; the "full read" case needs to fail if the whole
 529		 * firmware was not completely loaded.
 530		 */
 531		if ((fw_priv->opt_flags & FW_OPT_PARTIAL) && buffer)
 532			file_size_ptr = &file_size;
 533
 534		/* load firmware files from the mount namespace of init */
 535		rc = kernel_read_file_from_path_initns(path, fw_priv->offset,
 536						       &buffer, msize,
 537						       file_size_ptr,
 538						       READING_FIRMWARE);
 539		if (rc < 0) {
 540			if (rc != -ENOENT)
 541				dev_warn(device, "loading %s failed with error %d\n",
 542					 path, rc);
 543			else
 544				dev_dbg(device, "loading %s failed for no such file or directory.\n",
 545					 path);
 546			continue;
 547		}
 548		size = rc;
 549		rc = 0;
 550
 551		dev_dbg(device, "Loading firmware from %s\n", path);
 552		if (decompress) {
 553			dev_dbg(device, "f/w decompressing %s\n",
 554				fw_priv->fw_name);
 555			rc = decompress(device, fw_priv, size, buffer);
 556			/* discard the superfluous original content */
 557			vfree(buffer);
 558			buffer = NULL;
 559			if (rc) {
 560				fw_free_paged_buf(fw_priv);
 561				continue;
 562			}
 563		} else {
 564			dev_dbg(device, "direct-loading %s\n",
 565				fw_priv->fw_name);
 566			if (!fw_priv->data)
 567				fw_priv->data = buffer;
 568			fw_priv->size = size;
 569		}
 570		fw_state_done(fw_priv);
 571		break;
 572	}
 573	__putname(path);
 574
 575	return rc;
 576}
 577
 578/* firmware holds the ownership of pages */
 579static void firmware_free_data(const struct firmware *fw)
 580{
 581	/* Loaded directly? */
 582	if (!fw->priv) {
 583		vfree(fw->data);
 584		return;
 585	}
 586	free_fw_priv(fw->priv);
 587}
 588
 589/* store the pages buffer info firmware from buf */
 590static void fw_set_page_data(struct fw_priv *fw_priv, struct firmware *fw)
 591{
 592	fw->priv = fw_priv;
 593	fw->size = fw_priv->size;
 594	fw->data = fw_priv->data;
 595
 596	pr_debug("%s: fw-%s fw_priv=%p data=%p size=%u\n",
 597		 __func__, fw_priv->fw_name, fw_priv, fw_priv->data,
 598		 (unsigned int)fw_priv->size);
 599}
 600
 601#ifdef CONFIG_FW_CACHE
 602static void fw_name_devm_release(struct device *dev, void *res)
 603{
 604	struct fw_name_devm *fwn = res;
 605
 606	if (fwn->magic == (unsigned long)&fw_cache)
 607		pr_debug("%s: fw_name-%s devm-%p released\n",
 608				__func__, fwn->name, res);
 609	kfree_const(fwn->name);
 610}
 611
 612static int fw_devm_match(struct device *dev, void *res,
 613		void *match_data)
 614{
 615	struct fw_name_devm *fwn = res;
 616
 617	return (fwn->magic == (unsigned long)&fw_cache) &&
 618		!strcmp(fwn->name, match_data);
 619}
 620
 621static struct fw_name_devm *fw_find_devm_name(struct device *dev,
 622		const char *name)
 623{
 624	struct fw_name_devm *fwn;
 625
 626	fwn = devres_find(dev, fw_name_devm_release,
 627			  fw_devm_match, (void *)name);
 628	return fwn;
 629}
 630
 631static bool fw_cache_is_setup(struct device *dev, const char *name)
 632{
 633	struct fw_name_devm *fwn;
 634
 635	fwn = fw_find_devm_name(dev, name);
 636	if (fwn)
 637		return true;
 638
 639	return false;
 640}
 641
 642/* add firmware name into devres list */
 643static int fw_add_devm_name(struct device *dev, const char *name)
 644{
 645	struct fw_name_devm *fwn;
 646
 647	if (fw_cache_is_setup(dev, name))
 648		return 0;
 649
 650	fwn = devres_alloc(fw_name_devm_release, sizeof(struct fw_name_devm),
 651			   GFP_KERNEL);
 652	if (!fwn)
 653		return -ENOMEM;
 654	fwn->name = kstrdup_const(name, GFP_KERNEL);
 655	if (!fwn->name) {
 656		devres_free(fwn);
 657		return -ENOMEM;
 658	}
 659
 660	fwn->magic = (unsigned long)&fw_cache;
 661	devres_add(dev, fwn);
 662
 663	return 0;
 664}
 665#else
 666static bool fw_cache_is_setup(struct device *dev, const char *name)
 667{
 668	return false;
 669}
 670
 671static int fw_add_devm_name(struct device *dev, const char *name)
 672{
 673	return 0;
 674}
 675#endif
 676
 677int assign_fw(struct firmware *fw, struct device *device)
 678{
 679	struct fw_priv *fw_priv = fw->priv;
 680	int ret;
 681
 682	mutex_lock(&fw_lock);
 683	if (!fw_priv->size || fw_state_is_aborted(fw_priv)) {
 684		mutex_unlock(&fw_lock);
 685		return -ENOENT;
 686	}
 687
 688	/*
 689	 * add firmware name into devres list so that we can auto cache
 690	 * and uncache firmware for device.
 691	 *
 692	 * device may has been deleted already, but the problem
 693	 * should be fixed in devres or driver core.
 694	 */
 695	/* don't cache firmware handled without uevent */
 696	if (device && (fw_priv->opt_flags & FW_OPT_UEVENT) &&
 697	    !(fw_priv->opt_flags & FW_OPT_NOCACHE)) {
 698		ret = fw_add_devm_name(device, fw_priv->fw_name);
 699		if (ret) {
 700			mutex_unlock(&fw_lock);
 701			return ret;
 702		}
 703	}
 704
 705	/*
 706	 * After caching firmware image is started, let it piggyback
 707	 * on request firmware.
 708	 */
 709	if (!(fw_priv->opt_flags & FW_OPT_NOCACHE) &&
 710	    fw_priv->fwc->state == FW_LOADER_START_CACHE)
 711		fw_cache_piggyback_on_request(fw_priv);
 712
 713	/* pass the pages buffer to driver at the last minute */
 714	fw_set_page_data(fw_priv, fw);
 715	mutex_unlock(&fw_lock);
 716	return 0;
 717}
 718
 719/* prepare firmware and firmware_buf structs;
 720 * return 0 if a firmware is already assigned, 1 if need to load one,
 721 * or a negative error code
 722 */
 723static int
 724_request_firmware_prepare(struct firmware **firmware_p, const char *name,
 725			  struct device *device, void *dbuf, size_t size,
 726			  size_t offset, u32 opt_flags)
 727{
 728	struct firmware *firmware;
 729	struct fw_priv *fw_priv;
 730	int ret;
 731
 732	*firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
 733	if (!firmware) {
 734		dev_err(device, "%s: kmalloc(struct firmware) failed\n",
 735			__func__);
 736		return -ENOMEM;
 737	}
 738
 739	if (fw_get_builtin_firmware(firmware, name, dbuf, size)) {
 740		dev_dbg(device, "using built-in %s\n", name);
 741		return 0; /* assigned */
 742	}
 743
 744	ret = alloc_lookup_fw_priv(name, &fw_cache, &fw_priv, dbuf, size,
 745				   offset, opt_flags);
 746
 747	/*
 748	 * bind with 'priv' now to avoid warning in failure path
 749	 * of requesting firmware.
 750	 */
 751	firmware->priv = fw_priv;
 752
 753	if (ret > 0) {
 754		ret = fw_state_wait(fw_priv);
 755		if (!ret) {
 756			fw_set_page_data(fw_priv, firmware);
 757			return 0; /* assigned */
 758		}
 759	}
 760
 761	if (ret < 0)
 762		return ret;
 763	return 1; /* need to load */
 764}
 765
 766/*
 767 * Batched requests need only one wake, we need to do this step last due to the
 768 * fallback mechanism. The buf is protected with kref_get(), and it won't be
 769 * released until the last user calls release_firmware().
 770 *
 771 * Failed batched requests are possible as well, in such cases we just share
 772 * the struct fw_priv and won't release it until all requests are woken
 773 * and have gone through this same path.
 774 */
 775static void fw_abort_batch_reqs(struct firmware *fw)
 776{
 777	struct fw_priv *fw_priv;
 778
 779	/* Loaded directly? */
 780	if (!fw || !fw->priv)
 781		return;
 782
 783	fw_priv = fw->priv;
 784	mutex_lock(&fw_lock);
 785	if (!fw_state_is_aborted(fw_priv))
 786		fw_state_aborted(fw_priv);
 787	mutex_unlock(&fw_lock);
 788}
 789
 790/* called from request_firmware() and request_firmware_work_func() */
 791static int
 792_request_firmware(const struct firmware **firmware_p, const char *name,
 793		  struct device *device, void *buf, size_t size,
 794		  size_t offset, u32 opt_flags)
 795{
 796	struct firmware *fw = NULL;
 797	bool nondirect = false;
 798	int ret;
 799
 800	if (!firmware_p)
 801		return -EINVAL;
 802
 803	if (!name || name[0] == '\0') {
 804		ret = -EINVAL;
 805		goto out;
 806	}
 807
 808	ret = _request_firmware_prepare(&fw, name, device, buf, size,
 809					offset, opt_flags);
 810	if (ret <= 0) /* error or already assigned */
 811		goto out;
 812
 813	ret = fw_get_filesystem_firmware(device, fw->priv, "", NULL);
 814
 815	/* Only full reads can support decompression, platform, and sysfs. */
 816	if (!(opt_flags & FW_OPT_PARTIAL))
 817		nondirect = true;
 818
 819#ifdef CONFIG_FW_LOADER_COMPRESS
 820	if (ret == -ENOENT && nondirect)
 821		ret = fw_get_filesystem_firmware(device, fw->priv, ".xz",
 822						 fw_decompress_xz);
 823#endif
 824	if (ret == -ENOENT && nondirect)
 825		ret = firmware_fallback_platform(fw->priv);
 826
 827	if (ret) {
 828		if (!(opt_flags & FW_OPT_NO_WARN))
 829			dev_warn(device,
 830				 "Direct firmware load for %s failed with error %d\n",
 831				 name, ret);
 832		if (nondirect)
 833			ret = firmware_fallback_sysfs(fw, name, device,
 834						      opt_flags, ret);
 835	} else
 836		ret = assign_fw(fw, device);
 837
 838 out:
 839	if (ret < 0) {
 840		fw_abort_batch_reqs(fw);
 841		release_firmware(fw);
 842		fw = NULL;
 843	}
 844
 845	*firmware_p = fw;
 846	return ret;
 847}
 848
 849/**
 850 * request_firmware() - send firmware request and wait for it
 851 * @firmware_p: pointer to firmware image
 852 * @name: name of firmware file
 853 * @device: device for which firmware is being loaded
 854 *
 855 *      @firmware_p will be used to return a firmware image by the name
 856 *      of @name for device @device.
 857 *
 858 *      Should be called from user context where sleeping is allowed.
 859 *
 860 *      @name will be used as $FIRMWARE in the uevent environment and
 861 *      should be distinctive enough not to be confused with any other
 862 *      firmware image for this or any other device.
 863 *
 864 *	Caller must hold the reference count of @device.
 865 *
 866 *	The function can be called safely inside device's suspend and
 867 *	resume callback.
 868 **/
 869int
 870request_firmware(const struct firmware **firmware_p, const char *name,
 871		 struct device *device)
 872{
 873	int ret;
 874
 875	/* Need to pin this module until return */
 876	__module_get(THIS_MODULE);
 877	ret = _request_firmware(firmware_p, name, device, NULL, 0, 0,
 878				FW_OPT_UEVENT);
 879	module_put(THIS_MODULE);
 880	return ret;
 881}
 882EXPORT_SYMBOL(request_firmware);
 883
 884/**
 885 * firmware_request_nowarn() - request for an optional fw module
 886 * @firmware: pointer to firmware image
 887 * @name: name of firmware file
 888 * @device: device for which firmware is being loaded
 889 *
 890 * This function is similar in behaviour to request_firmware(), except it
 891 * doesn't produce warning messages when the file is not found. The sysfs
 892 * fallback mechanism is enabled if direct filesystem lookup fails. However,
 893 * failures to find the firmware file with it are still suppressed. It is
 894 * therefore up to the driver to check for the return value of this call and to
 895 * decide when to inform the users of errors.
 896 **/
 897int firmware_request_nowarn(const struct firmware **firmware, const char *name,
 898			    struct device *device)
 899{
 900	int ret;
 901
 902	/* Need to pin this module until return */
 903	__module_get(THIS_MODULE);
 904	ret = _request_firmware(firmware, name, device, NULL, 0, 0,
 905				FW_OPT_UEVENT | FW_OPT_NO_WARN);
 906	module_put(THIS_MODULE);
 907	return ret;
 908}
 909EXPORT_SYMBOL_GPL(firmware_request_nowarn);
 910
 911/**
 912 * request_firmware_direct() - load firmware directly without usermode helper
 913 * @firmware_p: pointer to firmware image
 914 * @name: name of firmware file
 915 * @device: device for which firmware is being loaded
 916 *
 917 * This function works pretty much like request_firmware(), but this doesn't
 918 * fall back to usermode helper even if the firmware couldn't be loaded
 919 * directly from fs.  Hence it's useful for loading optional firmwares, which
 920 * aren't always present, without extra long timeouts of udev.
 921 **/
 922int request_firmware_direct(const struct firmware **firmware_p,
 923			    const char *name, struct device *device)
 924{
 925	int ret;
 926
 927	__module_get(THIS_MODULE);
 928	ret = _request_firmware(firmware_p, name, device, NULL, 0, 0,
 929				FW_OPT_UEVENT | FW_OPT_NO_WARN |
 930				FW_OPT_NOFALLBACK_SYSFS);
 931	module_put(THIS_MODULE);
 932	return ret;
 933}
 934EXPORT_SYMBOL_GPL(request_firmware_direct);
 935
 936/**
 937 * firmware_request_platform() - request firmware with platform-fw fallback
 938 * @firmware: pointer to firmware image
 939 * @name: name of firmware file
 940 * @device: device for which firmware is being loaded
 941 *
 942 * This function is similar in behaviour to request_firmware, except that if
 943 * direct filesystem lookup fails, it will fallback to looking for a copy of the
 944 * requested firmware embedded in the platform's main (e.g. UEFI) firmware.
 945 **/
 946int firmware_request_platform(const struct firmware **firmware,
 947			      const char *name, struct device *device)
 948{
 949	int ret;
 950
 951	/* Need to pin this module until return */
 952	__module_get(THIS_MODULE);
 953	ret = _request_firmware(firmware, name, device, NULL, 0, 0,
 954				FW_OPT_UEVENT | FW_OPT_FALLBACK_PLATFORM);
 955	module_put(THIS_MODULE);
 956	return ret;
 957}
 958EXPORT_SYMBOL_GPL(firmware_request_platform);
 959
 960/**
 961 * firmware_request_cache() - cache firmware for suspend so resume can use it
 962 * @name: name of firmware file
 963 * @device: device for which firmware should be cached for
 964 *
 965 * There are some devices with an optimization that enables the device to not
 966 * require loading firmware on system reboot. This optimization may still
 967 * require the firmware present on resume from suspend. This routine can be
 968 * used to ensure the firmware is present on resume from suspend in these
 969 * situations. This helper is not compatible with drivers which use
 970 * request_firmware_into_buf() or request_firmware_nowait() with no uevent set.
 971 **/
 972int firmware_request_cache(struct device *device, const char *name)
 973{
 974	int ret;
 975
 976	mutex_lock(&fw_lock);
 977	ret = fw_add_devm_name(device, name);
 978	mutex_unlock(&fw_lock);
 979
 980	return ret;
 981}
 982EXPORT_SYMBOL_GPL(firmware_request_cache);
 983
 984/**
 985 * request_firmware_into_buf() - load firmware into a previously allocated buffer
 986 * @firmware_p: pointer to firmware image
 987 * @name: name of firmware file
 988 * @device: device for which firmware is being loaded and DMA region allocated
 989 * @buf: address of buffer to load firmware into
 990 * @size: size of buffer
 991 *
 992 * This function works pretty much like request_firmware(), but it doesn't
 993 * allocate a buffer to hold the firmware data. Instead, the firmware
 994 * is loaded directly into the buffer pointed to by @buf and the @firmware_p
 995 * data member is pointed at @buf.
 996 *
 997 * This function doesn't cache firmware either.
 998 */
 999int
1000request_firmware_into_buf(const struct firmware **firmware_p, const char *name,
1001			  struct device *device, void *buf, size_t size)
1002{
1003	int ret;
1004
1005	if (fw_cache_is_setup(device, name))
1006		return -EOPNOTSUPP;
1007
1008	__module_get(THIS_MODULE);
1009	ret = _request_firmware(firmware_p, name, device, buf, size, 0,
1010				FW_OPT_UEVENT | FW_OPT_NOCACHE);
1011	module_put(THIS_MODULE);
1012	return ret;
1013}
1014EXPORT_SYMBOL(request_firmware_into_buf);
1015
1016/**
1017 * request_partial_firmware_into_buf() - load partial firmware into a previously allocated buffer
1018 * @firmware_p: pointer to firmware image
1019 * @name: name of firmware file
1020 * @device: device for which firmware is being loaded and DMA region allocated
1021 * @buf: address of buffer to load firmware into
1022 * @size: size of buffer
1023 * @offset: offset into file to read
1024 *
1025 * This function works pretty much like request_firmware_into_buf except
1026 * it allows a partial read of the file.
1027 */
1028int
1029request_partial_firmware_into_buf(const struct firmware **firmware_p,
1030				  const char *name, struct device *device,
1031				  void *buf, size_t size, size_t offset)
1032{
1033	int ret;
1034
1035	if (fw_cache_is_setup(device, name))
1036		return -EOPNOTSUPP;
1037
1038	__module_get(THIS_MODULE);
1039	ret = _request_firmware(firmware_p, name, device, buf, size, offset,
1040				FW_OPT_UEVENT | FW_OPT_NOCACHE |
1041				FW_OPT_PARTIAL);
1042	module_put(THIS_MODULE);
1043	return ret;
1044}
1045EXPORT_SYMBOL(request_partial_firmware_into_buf);
1046
1047/**
1048 * release_firmware() - release the resource associated with a firmware image
1049 * @fw: firmware resource to release
1050 **/
1051void release_firmware(const struct firmware *fw)
1052{
1053	if (fw) {
1054		if (!fw_is_builtin_firmware(fw))
1055			firmware_free_data(fw);
1056		kfree(fw);
1057	}
1058}
1059EXPORT_SYMBOL(release_firmware);
1060
1061/* Async support */
1062struct firmware_work {
1063	struct work_struct work;
1064	struct module *module;
1065	const char *name;
1066	struct device *device;
1067	void *context;
1068	void (*cont)(const struct firmware *fw, void *context);
1069	u32 opt_flags;
1070};
1071
1072static void request_firmware_work_func(struct work_struct *work)
1073{
1074	struct firmware_work *fw_work;
1075	const struct firmware *fw;
1076
1077	fw_work = container_of(work, struct firmware_work, work);
1078
1079	_request_firmware(&fw, fw_work->name, fw_work->device, NULL, 0, 0,
1080			  fw_work->opt_flags);
1081	fw_work->cont(fw, fw_work->context);
1082	put_device(fw_work->device); /* taken in request_firmware_nowait() */
1083
1084	module_put(fw_work->module);
1085	kfree_const(fw_work->name);
1086	kfree(fw_work);
1087}
1088
1089/**
1090 * request_firmware_nowait() - asynchronous version of request_firmware
1091 * @module: module requesting the firmware
1092 * @uevent: sends uevent to copy the firmware image if this flag
1093 *	is non-zero else the firmware copy must be done manually.
1094 * @name: name of firmware file
1095 * @device: device for which firmware is being loaded
1096 * @gfp: allocation flags
1097 * @context: will be passed over to @cont, and
1098 *	@fw may be %NULL if firmware request fails.
1099 * @cont: function will be called asynchronously when the firmware
1100 *	request is over.
1101 *
1102 *	Caller must hold the reference count of @device.
1103 *
1104 *	Asynchronous variant of request_firmware() for user contexts:
1105 *		- sleep for as small periods as possible since it may
1106 *		  increase kernel boot time of built-in device drivers
1107 *		  requesting firmware in their ->probe() methods, if
1108 *		  @gfp is GFP_KERNEL.
1109 *
1110 *		- can't sleep at all if @gfp is GFP_ATOMIC.
1111 **/
1112int
1113request_firmware_nowait(
1114	struct module *module, bool uevent,
1115	const char *name, struct device *device, gfp_t gfp, void *context,
1116	void (*cont)(const struct firmware *fw, void *context))
1117{
1118	struct firmware_work *fw_work;
1119
1120	fw_work = kzalloc(sizeof(struct firmware_work), gfp);
1121	if (!fw_work)
1122		return -ENOMEM;
1123
1124	fw_work->module = module;
1125	fw_work->name = kstrdup_const(name, gfp);
1126	if (!fw_work->name) {
1127		kfree(fw_work);
1128		return -ENOMEM;
1129	}
1130	fw_work->device = device;
1131	fw_work->context = context;
1132	fw_work->cont = cont;
1133	fw_work->opt_flags = FW_OPT_NOWAIT |
1134		(uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER);
1135
1136	if (!uevent && fw_cache_is_setup(device, name)) {
1137		kfree_const(fw_work->name);
1138		kfree(fw_work);
1139		return -EOPNOTSUPP;
1140	}
1141
1142	if (!try_module_get(module)) {
1143		kfree_const(fw_work->name);
1144		kfree(fw_work);
1145		return -EFAULT;
1146	}
1147
1148	get_device(fw_work->device);
1149	INIT_WORK(&fw_work->work, request_firmware_work_func);
1150	schedule_work(&fw_work->work);
1151	return 0;
1152}
1153EXPORT_SYMBOL(request_firmware_nowait);
1154
1155#ifdef CONFIG_FW_CACHE
1156static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
1157
1158/**
1159 * cache_firmware() - cache one firmware image in kernel memory space
1160 * @fw_name: the firmware image name
1161 *
1162 * Cache firmware in kernel memory so that drivers can use it when
1163 * system isn't ready for them to request firmware image from userspace.
1164 * Once it returns successfully, driver can use request_firmware or its
1165 * nowait version to get the cached firmware without any interacting
1166 * with userspace
1167 *
1168 * Return 0 if the firmware image has been cached successfully
1169 * Return !0 otherwise
1170 *
1171 */
1172static int cache_firmware(const char *fw_name)
1173{
1174	int ret;
1175	const struct firmware *fw;
1176
1177	pr_debug("%s: %s\n", __func__, fw_name);
1178
1179	ret = request_firmware(&fw, fw_name, NULL);
1180	if (!ret)
1181		kfree(fw);
1182
1183	pr_debug("%s: %s ret=%d\n", __func__, fw_name, ret);
1184
1185	return ret;
1186}
1187
1188static struct fw_priv *lookup_fw_priv(const char *fw_name)
1189{
1190	struct fw_priv *tmp;
1191	struct firmware_cache *fwc = &fw_cache;
1192
1193	spin_lock(&fwc->lock);
1194	tmp = __lookup_fw_priv(fw_name);
1195	spin_unlock(&fwc->lock);
1196
1197	return tmp;
1198}
1199
1200/**
1201 * uncache_firmware() - remove one cached firmware image
1202 * @fw_name: the firmware image name
1203 *
1204 * Uncache one firmware image which has been cached successfully
1205 * before.
1206 *
1207 * Return 0 if the firmware cache has been removed successfully
1208 * Return !0 otherwise
1209 *
1210 */
1211static int uncache_firmware(const char *fw_name)
1212{
1213	struct fw_priv *fw_priv;
1214	struct firmware fw;
1215
1216	pr_debug("%s: %s\n", __func__, fw_name);
1217
1218	if (fw_get_builtin_firmware(&fw, fw_name, NULL, 0))
1219		return 0;
1220
1221	fw_priv = lookup_fw_priv(fw_name);
1222	if (fw_priv) {
1223		free_fw_priv(fw_priv);
1224		return 0;
1225	}
1226
1227	return -EINVAL;
1228}
1229
1230static struct fw_cache_entry *alloc_fw_cache_entry(const char *name)
1231{
1232	struct fw_cache_entry *fce;
1233
1234	fce = kzalloc(sizeof(*fce), GFP_ATOMIC);
1235	if (!fce)
1236		goto exit;
1237
1238	fce->name = kstrdup_const(name, GFP_ATOMIC);
1239	if (!fce->name) {
1240		kfree(fce);
1241		fce = NULL;
1242		goto exit;
1243	}
1244exit:
1245	return fce;
1246}
1247
1248static int __fw_entry_found(const char *name)
1249{
1250	struct firmware_cache *fwc = &fw_cache;
1251	struct fw_cache_entry *fce;
1252
1253	list_for_each_entry(fce, &fwc->fw_names, list) {
1254		if (!strcmp(fce->name, name))
1255			return 1;
1256	}
1257	return 0;
1258}
1259
1260static void fw_cache_piggyback_on_request(struct fw_priv *fw_priv)
1261{
1262	const char *name = fw_priv->fw_name;
1263	struct firmware_cache *fwc = fw_priv->fwc;
1264	struct fw_cache_entry *fce;
1265
1266	spin_lock(&fwc->name_lock);
1267	if (__fw_entry_found(name))
1268		goto found;
1269
1270	fce = alloc_fw_cache_entry(name);
1271	if (fce) {
1272		list_add(&fce->list, &fwc->fw_names);
1273		kref_get(&fw_priv->ref);
1274		pr_debug("%s: fw: %s\n", __func__, name);
1275	}
1276found:
1277	spin_unlock(&fwc->name_lock);
1278}
1279
1280static void free_fw_cache_entry(struct fw_cache_entry *fce)
1281{
1282	kfree_const(fce->name);
1283	kfree(fce);
1284}
1285
1286static void __async_dev_cache_fw_image(void *fw_entry,
1287				       async_cookie_t cookie)
1288{
1289	struct fw_cache_entry *fce = fw_entry;
1290	struct firmware_cache *fwc = &fw_cache;
1291	int ret;
1292
1293	ret = cache_firmware(fce->name);
1294	if (ret) {
1295		spin_lock(&fwc->name_lock);
1296		list_del(&fce->list);
1297		spin_unlock(&fwc->name_lock);
1298
1299		free_fw_cache_entry(fce);
1300	}
1301}
1302
1303/* called with dev->devres_lock held */
1304static void dev_create_fw_entry(struct device *dev, void *res,
1305				void *data)
1306{
1307	struct fw_name_devm *fwn = res;
1308	const char *fw_name = fwn->name;
1309	struct list_head *head = data;
1310	struct fw_cache_entry *fce;
1311
1312	fce = alloc_fw_cache_entry(fw_name);
1313	if (fce)
1314		list_add(&fce->list, head);
1315}
1316
1317static int devm_name_match(struct device *dev, void *res,
1318			   void *match_data)
1319{
1320	struct fw_name_devm *fwn = res;
1321	return (fwn->magic == (unsigned long)match_data);
1322}
1323
1324static void dev_cache_fw_image(struct device *dev, void *data)
1325{
1326	LIST_HEAD(todo);
1327	struct fw_cache_entry *fce;
1328	struct fw_cache_entry *fce_next;
1329	struct firmware_cache *fwc = &fw_cache;
1330
1331	devres_for_each_res(dev, fw_name_devm_release,
1332			    devm_name_match, &fw_cache,
1333			    dev_create_fw_entry, &todo);
1334
1335	list_for_each_entry_safe(fce, fce_next, &todo, list) {
1336		list_del(&fce->list);
1337
1338		spin_lock(&fwc->name_lock);
1339		/* only one cache entry for one firmware */
1340		if (!__fw_entry_found(fce->name)) {
1341			list_add(&fce->list, &fwc->fw_names);
1342		} else {
1343			free_fw_cache_entry(fce);
1344			fce = NULL;
1345		}
1346		spin_unlock(&fwc->name_lock);
1347
1348		if (fce)
1349			async_schedule_domain(__async_dev_cache_fw_image,
1350					      (void *)fce,
1351					      &fw_cache_domain);
1352	}
1353}
1354
1355static void __device_uncache_fw_images(void)
1356{
1357	struct firmware_cache *fwc = &fw_cache;
1358	struct fw_cache_entry *fce;
1359
1360	spin_lock(&fwc->name_lock);
1361	while (!list_empty(&fwc->fw_names)) {
1362		fce = list_entry(fwc->fw_names.next,
1363				struct fw_cache_entry, list);
1364		list_del(&fce->list);
1365		spin_unlock(&fwc->name_lock);
1366
1367		uncache_firmware(fce->name);
1368		free_fw_cache_entry(fce);
1369
1370		spin_lock(&fwc->name_lock);
1371	}
1372	spin_unlock(&fwc->name_lock);
1373}
1374
1375/**
1376 * device_cache_fw_images() - cache devices' firmware
1377 *
1378 * If one device called request_firmware or its nowait version
1379 * successfully before, the firmware names are recored into the
1380 * device's devres link list, so device_cache_fw_images can call
1381 * cache_firmware() to cache these firmwares for the device,
1382 * then the device driver can load its firmwares easily at
1383 * time when system is not ready to complete loading firmware.
1384 */
1385static void device_cache_fw_images(void)
1386{
1387	struct firmware_cache *fwc = &fw_cache;
1388	DEFINE_WAIT(wait);
1389
1390	pr_debug("%s\n", __func__);
1391
1392	/* cancel uncache work */
1393	cancel_delayed_work_sync(&fwc->work);
1394
1395	fw_fallback_set_cache_timeout();
1396
1397	mutex_lock(&fw_lock);
1398	fwc->state = FW_LOADER_START_CACHE;
1399	dpm_for_each_dev(NULL, dev_cache_fw_image);
1400	mutex_unlock(&fw_lock);
1401
1402	/* wait for completion of caching firmware for all devices */
1403	async_synchronize_full_domain(&fw_cache_domain);
1404
1405	fw_fallback_set_default_timeout();
1406}
1407
1408/**
1409 * device_uncache_fw_images() - uncache devices' firmware
1410 *
1411 * uncache all firmwares which have been cached successfully
1412 * by device_uncache_fw_images earlier
1413 */
1414static void device_uncache_fw_images(void)
1415{
1416	pr_debug("%s\n", __func__);
1417	__device_uncache_fw_images();
1418}
1419
1420static void device_uncache_fw_images_work(struct work_struct *work)
1421{
1422	device_uncache_fw_images();
1423}
1424
1425/**
1426 * device_uncache_fw_images_delay() - uncache devices firmwares
1427 * @delay: number of milliseconds to delay uncache device firmwares
1428 *
1429 * uncache all devices's firmwares which has been cached successfully
1430 * by device_cache_fw_images after @delay milliseconds.
1431 */
1432static void device_uncache_fw_images_delay(unsigned long delay)
1433{
1434	queue_delayed_work(system_power_efficient_wq, &fw_cache.work,
1435			   msecs_to_jiffies(delay));
1436}
1437
1438static int fw_pm_notify(struct notifier_block *notify_block,
1439			unsigned long mode, void *unused)
1440{
1441	switch (mode) {
1442	case PM_HIBERNATION_PREPARE:
1443	case PM_SUSPEND_PREPARE:
1444	case PM_RESTORE_PREPARE:
1445		/*
1446		 * kill pending fallback requests with a custom fallback
1447		 * to avoid stalling suspend.
1448		 */
1449		kill_pending_fw_fallback_reqs(true);
1450		device_cache_fw_images();
1451		break;
1452
1453	case PM_POST_SUSPEND:
1454	case PM_POST_HIBERNATION:
1455	case PM_POST_RESTORE:
1456		/*
1457		 * In case that system sleep failed and syscore_suspend is
1458		 * not called.
1459		 */
1460		mutex_lock(&fw_lock);
1461		fw_cache.state = FW_LOADER_NO_CACHE;
1462		mutex_unlock(&fw_lock);
1463
1464		device_uncache_fw_images_delay(10 * MSEC_PER_SEC);
1465		break;
1466	}
1467
1468	return 0;
1469}
1470
1471/* stop caching firmware once syscore_suspend is reached */
1472static int fw_suspend(void)
1473{
1474	fw_cache.state = FW_LOADER_NO_CACHE;
1475	return 0;
1476}
1477
1478static struct syscore_ops fw_syscore_ops = {
1479	.suspend = fw_suspend,
1480};
1481
1482static int __init register_fw_pm_ops(void)
1483{
1484	int ret;
1485
1486	spin_lock_init(&fw_cache.name_lock);
1487	INIT_LIST_HEAD(&fw_cache.fw_names);
1488
1489	INIT_DELAYED_WORK(&fw_cache.work,
1490			  device_uncache_fw_images_work);
1491
1492	fw_cache.pm_notify.notifier_call = fw_pm_notify;
1493	ret = register_pm_notifier(&fw_cache.pm_notify);
1494	if (ret)
1495		return ret;
1496
1497	register_syscore_ops(&fw_syscore_ops);
1498
1499	return ret;
1500}
1501
1502static inline void unregister_fw_pm_ops(void)
1503{
1504	unregister_syscore_ops(&fw_syscore_ops);
1505	unregister_pm_notifier(&fw_cache.pm_notify);
1506}
1507#else
1508static void fw_cache_piggyback_on_request(struct fw_priv *fw_priv)
1509{
1510}
1511static inline int register_fw_pm_ops(void)
1512{
1513	return 0;
1514}
1515static inline void unregister_fw_pm_ops(void)
1516{
1517}
1518#endif
1519
1520static void __init fw_cache_init(void)
1521{
1522	spin_lock_init(&fw_cache.lock);
1523	INIT_LIST_HEAD(&fw_cache.head);
1524	fw_cache.state = FW_LOADER_NO_CACHE;
1525}
1526
1527static int fw_shutdown_notify(struct notifier_block *unused1,
1528			      unsigned long unused2, void *unused3)
1529{
1530	/*
1531	 * Kill all pending fallback requests to avoid both stalling shutdown,
1532	 * and avoid a deadlock with the usermode_lock.
1533	 */
1534	kill_pending_fw_fallback_reqs(false);
1535
1536	return NOTIFY_DONE;
1537}
1538
1539static struct notifier_block fw_shutdown_nb = {
1540	.notifier_call = fw_shutdown_notify,
1541};
1542
1543static int __init firmware_class_init(void)
1544{
1545	int ret;
1546
1547	/* No need to unfold these on exit */
1548	fw_cache_init();
1549
1550	ret = register_fw_pm_ops();
1551	if (ret)
1552		return ret;
1553
1554	ret = register_reboot_notifier(&fw_shutdown_nb);
1555	if (ret)
1556		goto out;
1557
1558	return register_sysfs_loader();
1559
1560out:
1561	unregister_fw_pm_ops();
1562	return ret;
1563}
1564
1565static void __exit firmware_class_exit(void)
1566{
1567	unregister_fw_pm_ops();
1568	unregister_reboot_notifier(&fw_shutdown_nb);
1569	unregister_sysfs_loader();
1570}
1571
1572fs_initcall(firmware_class_init);
1573module_exit(firmware_class_exit);