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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/zstd.h>
  39#include <linux/xz.h>
  40
  41#include <generated/utsrelease.h>
  42
  43#include "../base.h"
  44#include "firmware.h"
  45#include "fallback.h"
  46
  47MODULE_AUTHOR("Manuel Estrada Sainz");
  48MODULE_DESCRIPTION("Multi purpose firmware loading support");
  49MODULE_LICENSE("GPL");
  50
  51struct firmware_cache {
  52	/* firmware_buf instance will be added into the below list */
  53	spinlock_t lock;
  54	struct list_head head;
  55	int state;
  56
  57#ifdef CONFIG_FW_CACHE
  58	/*
  59	 * Names of firmware images which have been cached successfully
  60	 * will be added into the below list so that device uncache
  61	 * helper can trace which firmware images have been cached
  62	 * before.
  63	 */
  64	spinlock_t name_lock;
  65	struct list_head fw_names;
  66
  67	struct delayed_work work;
  68
  69	struct notifier_block   pm_notify;
  70#endif
  71};
  72
  73struct fw_cache_entry {
  74	struct list_head list;
  75	const char *name;
  76};
  77
  78struct fw_name_devm {
  79	unsigned long magic;
  80	const char *name;
  81};
  82
  83static inline struct fw_priv *to_fw_priv(struct kref *ref)
  84{
  85	return container_of(ref, struct fw_priv, ref);
  86}
  87
  88#define	FW_LOADER_NO_CACHE	0
  89#define	FW_LOADER_START_CACHE	1
  90
  91/* fw_lock could be moved to 'struct fw_sysfs' but since it is just
  92 * guarding for corner cases a global lock should be OK */
  93DEFINE_MUTEX(fw_lock);
  94
  95struct firmware_cache fw_cache;
  96bool fw_load_abort_all;
  97
  98void fw_state_init(struct fw_priv *fw_priv)
  99{
 100	struct fw_state *fw_st = &fw_priv->fw_st;
 101
 102	init_completion(&fw_st->completion);
 103	fw_st->status = FW_STATUS_UNKNOWN;
 104}
 105
 106static inline int fw_state_wait(struct fw_priv *fw_priv)
 107{
 108	return __fw_state_wait_common(fw_priv, MAX_SCHEDULE_TIMEOUT);
 109}
 110
 111static void fw_cache_piggyback_on_request(struct fw_priv *fw_priv);
 112
 113static struct fw_priv *__allocate_fw_priv(const char *fw_name,
 114					  struct firmware_cache *fwc,
 115					  void *dbuf,
 116					  size_t size,
 117					  size_t offset,
 118					  u32 opt_flags)
 119{
 120	struct fw_priv *fw_priv;
 121
 122	/* For a partial read, the buffer must be preallocated. */
 123	if ((opt_flags & FW_OPT_PARTIAL) && !dbuf)
 124		return NULL;
 125
 126	/* Only partial reads are allowed to use an offset. */
 127	if (offset != 0 && !(opt_flags & FW_OPT_PARTIAL))
 128		return NULL;
 129
 130	fw_priv = kzalloc(sizeof(*fw_priv), GFP_ATOMIC);
 131	if (!fw_priv)
 132		return NULL;
 133
 134	fw_priv->fw_name = kstrdup_const(fw_name, GFP_ATOMIC);
 135	if (!fw_priv->fw_name) {
 136		kfree(fw_priv);
 137		return NULL;
 138	}
 139
 140	kref_init(&fw_priv->ref);
 141	fw_priv->fwc = fwc;
 142	fw_priv->data = dbuf;
 143	fw_priv->allocated_size = size;
 144	fw_priv->offset = offset;
 145	fw_priv->opt_flags = opt_flags;
 146	fw_state_init(fw_priv);
 147#ifdef CONFIG_FW_LOADER_USER_HELPER
 148	INIT_LIST_HEAD(&fw_priv->pending_list);
 149#endif
 150
 151	pr_debug("%s: fw-%s fw_priv=%p\n", __func__, fw_name, fw_priv);
 152
 153	return fw_priv;
 154}
 155
 156static struct fw_priv *__lookup_fw_priv(const char *fw_name)
 157{
 158	struct fw_priv *tmp;
 159	struct firmware_cache *fwc = &fw_cache;
 160
 161	list_for_each_entry(tmp, &fwc->head, list)
 162		if (!strcmp(tmp->fw_name, fw_name))
 163			return tmp;
 164	return NULL;
 165}
 166
 167/* Returns 1 for batching firmware requests with the same name */
 168int alloc_lookup_fw_priv(const char *fw_name, struct firmware_cache *fwc,
 169			 struct fw_priv **fw_priv, void *dbuf, size_t size,
 170			 size_t offset, u32 opt_flags)
 171{
 172	struct fw_priv *tmp;
 173
 174	spin_lock(&fwc->lock);
 175	/*
 176	 * Do not merge requests that are marked to be non-cached or
 177	 * are performing partial reads.
 178	 */
 179	if (!(opt_flags & (FW_OPT_NOCACHE | FW_OPT_PARTIAL))) {
 180		tmp = __lookup_fw_priv(fw_name);
 181		if (tmp) {
 182			kref_get(&tmp->ref);
 183			spin_unlock(&fwc->lock);
 184			*fw_priv = tmp;
 185			pr_debug("batched request - sharing the same struct fw_priv and lookup for multiple requests\n");
 186			return 1;
 187		}
 188	}
 189
 190	tmp = __allocate_fw_priv(fw_name, fwc, dbuf, size, offset, opt_flags);
 191	if (tmp) {
 192		INIT_LIST_HEAD(&tmp->list);
 193		if (!(opt_flags & FW_OPT_NOCACHE))
 194			list_add(&tmp->list, &fwc->head);
 195	}
 196	spin_unlock(&fwc->lock);
 197
 198	*fw_priv = tmp;
 199
 200	return tmp ? 0 : -ENOMEM;
 201}
 202
 203static void __free_fw_priv(struct kref *ref)
 204	__releases(&fwc->lock)
 205{
 206	struct fw_priv *fw_priv = to_fw_priv(ref);
 207	struct firmware_cache *fwc = fw_priv->fwc;
 208
 209	pr_debug("%s: fw-%s fw_priv=%p data=%p size=%u\n",
 210		 __func__, fw_priv->fw_name, fw_priv, fw_priv->data,
 211		 (unsigned int)fw_priv->size);
 212
 213	list_del(&fw_priv->list);
 214	spin_unlock(&fwc->lock);
 215
 216	if (fw_is_paged_buf(fw_priv))
 217		fw_free_paged_buf(fw_priv);
 218	else if (!fw_priv->allocated_size)
 219		vfree(fw_priv->data);
 220
 221	kfree_const(fw_priv->fw_name);
 222	kfree(fw_priv);
 223}
 224
 225void free_fw_priv(struct fw_priv *fw_priv)
 226{
 227	struct firmware_cache *fwc = fw_priv->fwc;
 228	spin_lock(&fwc->lock);
 229	if (!kref_put(&fw_priv->ref, __free_fw_priv))
 230		spin_unlock(&fwc->lock);
 231}
 232
 233#ifdef CONFIG_FW_LOADER_PAGED_BUF
 234bool fw_is_paged_buf(struct fw_priv *fw_priv)
 235{
 236	return fw_priv->is_paged_buf;
 237}
 238
 239void fw_free_paged_buf(struct fw_priv *fw_priv)
 240{
 241	int i;
 242
 243	if (!fw_priv->pages)
 244		return;
 245
 246	vunmap(fw_priv->data);
 247
 248	for (i = 0; i < fw_priv->nr_pages; i++)
 249		__free_page(fw_priv->pages[i]);
 250	kvfree(fw_priv->pages);
 251	fw_priv->pages = NULL;
 252	fw_priv->page_array_size = 0;
 253	fw_priv->nr_pages = 0;
 254	fw_priv->data = NULL;
 255	fw_priv->size = 0;
 256}
 257
 258int fw_grow_paged_buf(struct fw_priv *fw_priv, int pages_needed)
 259{
 260	/* If the array of pages is too small, grow it */
 261	if (fw_priv->page_array_size < pages_needed) {
 262		int new_array_size = max(pages_needed,
 263					 fw_priv->page_array_size * 2);
 264		struct page **new_pages;
 265
 266		new_pages = kvmalloc_array(new_array_size, sizeof(void *),
 267					   GFP_KERNEL);
 268		if (!new_pages)
 269			return -ENOMEM;
 270		memcpy(new_pages, fw_priv->pages,
 271		       fw_priv->page_array_size * sizeof(void *));
 272		memset(&new_pages[fw_priv->page_array_size], 0, sizeof(void *) *
 273		       (new_array_size - fw_priv->page_array_size));
 274		kvfree(fw_priv->pages);
 275		fw_priv->pages = new_pages;
 276		fw_priv->page_array_size = new_array_size;
 277	}
 278
 279	while (fw_priv->nr_pages < pages_needed) {
 280		fw_priv->pages[fw_priv->nr_pages] =
 281			alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
 282
 283		if (!fw_priv->pages[fw_priv->nr_pages])
 284			return -ENOMEM;
 285		fw_priv->nr_pages++;
 286	}
 287
 288	return 0;
 289}
 290
 291int fw_map_paged_buf(struct fw_priv *fw_priv)
 292{
 293	/* one pages buffer should be mapped/unmapped only once */
 294	if (!fw_priv->pages)
 295		return 0;
 296
 297	vunmap(fw_priv->data);
 298	fw_priv->data = vmap(fw_priv->pages, fw_priv->nr_pages, 0,
 299			     PAGE_KERNEL_RO);
 300	if (!fw_priv->data)
 301		return -ENOMEM;
 302
 303	return 0;
 304}
 305#endif
 306
 307/*
 308 * ZSTD-compressed firmware support
 309 */
 310#ifdef CONFIG_FW_LOADER_COMPRESS_ZSTD
 311static int fw_decompress_zstd(struct device *dev, struct fw_priv *fw_priv,
 312			      size_t in_size, const void *in_buffer)
 313{
 314	size_t len, out_size, workspace_size;
 315	void *workspace, *out_buf;
 316	zstd_dctx *ctx;
 317	int err;
 318
 319	if (fw_priv->allocated_size) {
 320		out_size = fw_priv->allocated_size;
 321		out_buf = fw_priv->data;
 322	} else {
 323		zstd_frame_header params;
 324
 325		if (zstd_get_frame_header(&params, in_buffer, in_size) ||
 326		    params.frameContentSize == ZSTD_CONTENTSIZE_UNKNOWN) {
 327			dev_dbg(dev, "%s: invalid zstd header\n", __func__);
 328			return -EINVAL;
 329		}
 330		out_size = params.frameContentSize;
 331		out_buf = vzalloc(out_size);
 332		if (!out_buf)
 333			return -ENOMEM;
 334	}
 335
 336	workspace_size = zstd_dctx_workspace_bound();
 337	workspace = kvzalloc(workspace_size, GFP_KERNEL);
 338	if (!workspace) {
 339		err = -ENOMEM;
 340		goto error;
 341	}
 342
 343	ctx = zstd_init_dctx(workspace, workspace_size);
 344	if (!ctx) {
 345		dev_dbg(dev, "%s: failed to initialize context\n", __func__);
 346		err = -EINVAL;
 347		goto error;
 348	}
 349
 350	len = zstd_decompress_dctx(ctx, out_buf, out_size, in_buffer, in_size);
 351	if (zstd_is_error(len)) {
 352		dev_dbg(dev, "%s: failed to decompress: %d\n", __func__,
 353			zstd_get_error_code(len));
 354		err = -EINVAL;
 355		goto error;
 356	}
 357
 358	if (!fw_priv->allocated_size)
 359		fw_priv->data = out_buf;
 360	fw_priv->size = len;
 361	err = 0;
 362
 363 error:
 364	kvfree(workspace);
 365	if (err && !fw_priv->allocated_size)
 366		vfree(out_buf);
 367	return err;
 368}
 369#endif /* CONFIG_FW_LOADER_COMPRESS_ZSTD */
 370
 371/*
 372 * XZ-compressed firmware support
 373 */
 374#ifdef CONFIG_FW_LOADER_COMPRESS_XZ
 375/* show an error and return the standard error code */
 376static int fw_decompress_xz_error(struct device *dev, enum xz_ret xz_ret)
 377{
 378	if (xz_ret != XZ_STREAM_END) {
 379		dev_warn(dev, "xz decompression failed (xz_ret=%d)\n", xz_ret);
 380		return xz_ret == XZ_MEM_ERROR ? -ENOMEM : -EINVAL;
 381	}
 382	return 0;
 383}
 384
 385/* single-shot decompression onto the pre-allocated buffer */
 386static int fw_decompress_xz_single(struct device *dev, struct fw_priv *fw_priv,
 387				   size_t in_size, const void *in_buffer)
 388{
 389	struct xz_dec *xz_dec;
 390	struct xz_buf xz_buf;
 391	enum xz_ret xz_ret;
 392
 393	xz_dec = xz_dec_init(XZ_SINGLE, (u32)-1);
 394	if (!xz_dec)
 395		return -ENOMEM;
 396
 397	xz_buf.in_size = in_size;
 398	xz_buf.in = in_buffer;
 399	xz_buf.in_pos = 0;
 400	xz_buf.out_size = fw_priv->allocated_size;
 401	xz_buf.out = fw_priv->data;
 402	xz_buf.out_pos = 0;
 403
 404	xz_ret = xz_dec_run(xz_dec, &xz_buf);
 405	xz_dec_end(xz_dec);
 406
 407	fw_priv->size = xz_buf.out_pos;
 408	return fw_decompress_xz_error(dev, xz_ret);
 409}
 410
 411/* decompression on paged buffer and map it */
 412static int fw_decompress_xz_pages(struct device *dev, struct fw_priv *fw_priv,
 413				  size_t in_size, const void *in_buffer)
 414{
 415	struct xz_dec *xz_dec;
 416	struct xz_buf xz_buf;
 417	enum xz_ret xz_ret;
 418	struct page *page;
 419	int err = 0;
 420
 421	xz_dec = xz_dec_init(XZ_DYNALLOC, (u32)-1);
 422	if (!xz_dec)
 423		return -ENOMEM;
 424
 425	xz_buf.in_size = in_size;
 426	xz_buf.in = in_buffer;
 427	xz_buf.in_pos = 0;
 428
 429	fw_priv->is_paged_buf = true;
 430	fw_priv->size = 0;
 431	do {
 432		if (fw_grow_paged_buf(fw_priv, fw_priv->nr_pages + 1)) {
 433			err = -ENOMEM;
 434			goto out;
 435		}
 436
 437		/* decompress onto the new allocated page */
 438		page = fw_priv->pages[fw_priv->nr_pages - 1];
 439		xz_buf.out = kmap_local_page(page);
 440		xz_buf.out_pos = 0;
 441		xz_buf.out_size = PAGE_SIZE;
 442		xz_ret = xz_dec_run(xz_dec, &xz_buf);
 443		kunmap_local(xz_buf.out);
 444		fw_priv->size += xz_buf.out_pos;
 445		/* partial decompression means either end or error */
 446		if (xz_buf.out_pos != PAGE_SIZE)
 447			break;
 448	} while (xz_ret == XZ_OK);
 449
 450	err = fw_decompress_xz_error(dev, xz_ret);
 451	if (!err)
 452		err = fw_map_paged_buf(fw_priv);
 453
 454 out:
 455	xz_dec_end(xz_dec);
 456	return err;
 457}
 458
 459static int fw_decompress_xz(struct device *dev, struct fw_priv *fw_priv,
 460			    size_t in_size, const void *in_buffer)
 461{
 462	/* if the buffer is pre-allocated, we can perform in single-shot mode */
 463	if (fw_priv->data)
 464		return fw_decompress_xz_single(dev, fw_priv, in_size, in_buffer);
 465	else
 466		return fw_decompress_xz_pages(dev, fw_priv, in_size, in_buffer);
 467}
 468#endif /* CONFIG_FW_LOADER_COMPRESS_XZ */
 469
 470/* direct firmware loading support */
 471static char fw_path_para[256];
 472static const char * const fw_path[] = {
 473	fw_path_para,
 474	"/lib/firmware/updates/" UTS_RELEASE,
 475	"/lib/firmware/updates",
 476	"/lib/firmware/" UTS_RELEASE,
 477	"/lib/firmware"
 478};
 479
 480/*
 481 * Typical usage is that passing 'firmware_class.path=$CUSTOMIZED_PATH'
 482 * from kernel command line because firmware_class is generally built in
 483 * kernel instead of module.
 484 */
 485module_param_string(path, fw_path_para, sizeof(fw_path_para), 0644);
 486MODULE_PARM_DESC(path, "customized firmware image search path with a higher priority than default path");
 487
 488static int
 489fw_get_filesystem_firmware(struct device *device, struct fw_priv *fw_priv,
 490			   const char *suffix,
 491			   int (*decompress)(struct device *dev,
 492					     struct fw_priv *fw_priv,
 493					     size_t in_size,
 494					     const void *in_buffer))
 495{
 496	size_t size;
 497	int i, len, maxlen = 0;
 498	int rc = -ENOENT;
 499	char *path, *nt = NULL;
 500	size_t msize = INT_MAX;
 501	void *buffer = NULL;
 502
 503	/* Already populated data member means we're loading into a buffer */
 504	if (!decompress && fw_priv->data) {
 505		buffer = fw_priv->data;
 506		msize = fw_priv->allocated_size;
 507	}
 508
 509	path = __getname();
 510	if (!path)
 511		return -ENOMEM;
 512
 513	wait_for_initramfs();
 514	for (i = 0; i < ARRAY_SIZE(fw_path); i++) {
 515		size_t file_size = 0;
 516		size_t *file_size_ptr = NULL;
 517
 518		/* skip the unset customized path */
 519		if (!fw_path[i][0])
 520			continue;
 521
 522		/* strip off \n from customized path */
 523		maxlen = strlen(fw_path[i]);
 524		if (i == 0) {
 525			nt = strchr(fw_path[i], '\n');
 526			if (nt)
 527				maxlen = nt - fw_path[i];
 528		}
 529
 530		len = snprintf(path, PATH_MAX, "%.*s/%s%s",
 531			       maxlen, fw_path[i],
 532			       fw_priv->fw_name, suffix);
 533		if (len >= PATH_MAX) {
 534			rc = -ENAMETOOLONG;
 535			break;
 536		}
 537
 538		fw_priv->size = 0;
 539
 540		/*
 541		 * The total file size is only examined when doing a partial
 542		 * read; the "full read" case needs to fail if the whole
 543		 * firmware was not completely loaded.
 544		 */
 545		if ((fw_priv->opt_flags & FW_OPT_PARTIAL) && buffer)
 546			file_size_ptr = &file_size;
 547
 548		/* load firmware files from the mount namespace of init */
 549		rc = kernel_read_file_from_path_initns(path, fw_priv->offset,
 550						       &buffer, msize,
 551						       file_size_ptr,
 552						       READING_FIRMWARE);
 553		if (rc < 0) {
 554			if (!(fw_priv->opt_flags & FW_OPT_NO_WARN)) {
 555				if (rc != -ENOENT)
 556					dev_warn(device,
 557						 "loading %s failed with error %d\n",
 558						 path, rc);
 559				else
 560					dev_dbg(device,
 561						"loading %s failed for no such file or directory.\n",
 562						path);
 563			}
 564			continue;
 565		}
 566		size = rc;
 567		rc = 0;
 568
 569		dev_dbg(device, "Loading firmware from %s\n", path);
 570		if (decompress) {
 571			dev_dbg(device, "f/w decompressing %s\n",
 572				fw_priv->fw_name);
 573			rc = decompress(device, fw_priv, size, buffer);
 574			/* discard the superfluous original content */
 575			vfree(buffer);
 576			buffer = NULL;
 577			if (rc) {
 578				fw_free_paged_buf(fw_priv);
 579				continue;
 580			}
 581		} else {
 582			dev_dbg(device, "direct-loading %s\n",
 583				fw_priv->fw_name);
 584			if (!fw_priv->data)
 585				fw_priv->data = buffer;
 586			fw_priv->size = size;
 587		}
 588		fw_state_done(fw_priv);
 589		break;
 590	}
 591	__putname(path);
 592
 593	return rc;
 594}
 595
 596/* firmware holds the ownership of pages */
 597static void firmware_free_data(const struct firmware *fw)
 598{
 599	/* Loaded directly? */
 600	if (!fw->priv) {
 601		vfree(fw->data);
 602		return;
 603	}
 604	free_fw_priv(fw->priv);
 605}
 606
 607/* store the pages buffer info firmware from buf */
 608static void fw_set_page_data(struct fw_priv *fw_priv, struct firmware *fw)
 609{
 610	fw->priv = fw_priv;
 611	fw->size = fw_priv->size;
 612	fw->data = fw_priv->data;
 613
 614	pr_debug("%s: fw-%s fw_priv=%p data=%p size=%u\n",
 615		 __func__, fw_priv->fw_name, fw_priv, fw_priv->data,
 616		 (unsigned int)fw_priv->size);
 617}
 618
 619#ifdef CONFIG_FW_CACHE
 620static void fw_name_devm_release(struct device *dev, void *res)
 621{
 622	struct fw_name_devm *fwn = res;
 623
 624	if (fwn->magic == (unsigned long)&fw_cache)
 625		pr_debug("%s: fw_name-%s devm-%p released\n",
 626				__func__, fwn->name, res);
 627	kfree_const(fwn->name);
 628}
 629
 630static int fw_devm_match(struct device *dev, void *res,
 631		void *match_data)
 632{
 633	struct fw_name_devm *fwn = res;
 634
 635	return (fwn->magic == (unsigned long)&fw_cache) &&
 636		!strcmp(fwn->name, match_data);
 637}
 638
 639static struct fw_name_devm *fw_find_devm_name(struct device *dev,
 640		const char *name)
 641{
 642	struct fw_name_devm *fwn;
 643
 644	fwn = devres_find(dev, fw_name_devm_release,
 645			  fw_devm_match, (void *)name);
 646	return fwn;
 647}
 648
 649static bool fw_cache_is_setup(struct device *dev, const char *name)
 650{
 651	struct fw_name_devm *fwn;
 652
 653	fwn = fw_find_devm_name(dev, name);
 654	if (fwn)
 655		return true;
 656
 657	return false;
 658}
 659
 660/* add firmware name into devres list */
 661static int fw_add_devm_name(struct device *dev, const char *name)
 662{
 663	struct fw_name_devm *fwn;
 664
 665	if (fw_cache_is_setup(dev, name))
 666		return 0;
 667
 668	fwn = devres_alloc(fw_name_devm_release, sizeof(struct fw_name_devm),
 669			   GFP_KERNEL);
 670	if (!fwn)
 671		return -ENOMEM;
 672	fwn->name = kstrdup_const(name, GFP_KERNEL);
 673	if (!fwn->name) {
 674		devres_free(fwn);
 675		return -ENOMEM;
 676	}
 677
 678	fwn->magic = (unsigned long)&fw_cache;
 679	devres_add(dev, fwn);
 680
 681	return 0;
 682}
 683#else
 684static bool fw_cache_is_setup(struct device *dev, const char *name)
 685{
 686	return false;
 687}
 688
 689static int fw_add_devm_name(struct device *dev, const char *name)
 690{
 691	return 0;
 692}
 693#endif
 694
 695int assign_fw(struct firmware *fw, struct device *device)
 696{
 697	struct fw_priv *fw_priv = fw->priv;
 698	int ret;
 699
 700	mutex_lock(&fw_lock);
 701	if (!fw_priv->size || fw_state_is_aborted(fw_priv)) {
 702		mutex_unlock(&fw_lock);
 703		return -ENOENT;
 704	}
 705
 706	/*
 707	 * add firmware name into devres list so that we can auto cache
 708	 * and uncache firmware for device.
 709	 *
 710	 * device may has been deleted already, but the problem
 711	 * should be fixed in devres or driver core.
 712	 */
 713	/* don't cache firmware handled without uevent */
 714	if (device && (fw_priv->opt_flags & FW_OPT_UEVENT) &&
 715	    !(fw_priv->opt_flags & FW_OPT_NOCACHE)) {
 716		ret = fw_add_devm_name(device, fw_priv->fw_name);
 717		if (ret) {
 718			mutex_unlock(&fw_lock);
 719			return ret;
 720		}
 721	}
 722
 723	/*
 724	 * After caching firmware image is started, let it piggyback
 725	 * on request firmware.
 726	 */
 727	if (!(fw_priv->opt_flags & FW_OPT_NOCACHE) &&
 728	    fw_priv->fwc->state == FW_LOADER_START_CACHE)
 729		fw_cache_piggyback_on_request(fw_priv);
 730
 731	/* pass the pages buffer to driver at the last minute */
 732	fw_set_page_data(fw_priv, fw);
 733	mutex_unlock(&fw_lock);
 734	return 0;
 735}
 736
 737/* prepare firmware and firmware_buf structs;
 738 * return 0 if a firmware is already assigned, 1 if need to load one,
 739 * or a negative error code
 740 */
 741static int
 742_request_firmware_prepare(struct firmware **firmware_p, const char *name,
 743			  struct device *device, void *dbuf, size_t size,
 744			  size_t offset, u32 opt_flags)
 745{
 746	struct firmware *firmware;
 747	struct fw_priv *fw_priv;
 748	int ret;
 749
 750	*firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
 751	if (!firmware) {
 752		dev_err(device, "%s: kmalloc(struct firmware) failed\n",
 753			__func__);
 754		return -ENOMEM;
 755	}
 756
 757	if (firmware_request_builtin_buf(firmware, name, dbuf, size)) {
 758		dev_dbg(device, "using built-in %s\n", name);
 759		return 0; /* assigned */
 760	}
 761
 762	ret = alloc_lookup_fw_priv(name, &fw_cache, &fw_priv, dbuf, size,
 763				   offset, opt_flags);
 764
 765	/*
 766	 * bind with 'priv' now to avoid warning in failure path
 767	 * of requesting firmware.
 768	 */
 769	firmware->priv = fw_priv;
 770
 771	if (ret > 0) {
 772		ret = fw_state_wait(fw_priv);
 773		if (!ret) {
 774			fw_set_page_data(fw_priv, firmware);
 775			return 0; /* assigned */
 776		}
 777	}
 778
 779	if (ret < 0)
 780		return ret;
 781	return 1; /* need to load */
 782}
 783
 784/*
 785 * Batched requests need only one wake, we need to do this step last due to the
 786 * fallback mechanism. The buf is protected with kref_get(), and it won't be
 787 * released until the last user calls release_firmware().
 788 *
 789 * Failed batched requests are possible as well, in such cases we just share
 790 * the struct fw_priv and won't release it until all requests are woken
 791 * and have gone through this same path.
 792 */
 793static void fw_abort_batch_reqs(struct firmware *fw)
 794{
 795	struct fw_priv *fw_priv;
 796
 797	/* Loaded directly? */
 798	if (!fw || !fw->priv)
 799		return;
 800
 801	fw_priv = fw->priv;
 802	mutex_lock(&fw_lock);
 803	if (!fw_state_is_aborted(fw_priv))
 804		fw_state_aborted(fw_priv);
 805	mutex_unlock(&fw_lock);
 806}
 807
 808#if defined(CONFIG_FW_LOADER_DEBUG)
 809#include <crypto/hash.h>
 810#include <crypto/sha2.h>
 811
 812static void fw_log_firmware_info(const struct firmware *fw, const char *name, struct device *device)
 813{
 814	struct shash_desc *shash;
 815	struct crypto_shash *alg;
 816	u8 *sha256buf;
 817	char *outbuf;
 818
 819	alg = crypto_alloc_shash("sha256", 0, 0);
 820	if (IS_ERR(alg))
 821		return;
 822
 823	sha256buf = kmalloc(SHA256_DIGEST_SIZE, GFP_KERNEL);
 824	outbuf = kmalloc(SHA256_BLOCK_SIZE + 1, GFP_KERNEL);
 825	shash = kmalloc(sizeof(*shash) + crypto_shash_descsize(alg), GFP_KERNEL);
 826	if (!sha256buf || !outbuf || !shash)
 827		goto out_free;
 828
 829	shash->tfm = alg;
 830
 831	if (crypto_shash_digest(shash, fw->data, fw->size, sha256buf) < 0)
 832		goto out_shash;
 833
 834	for (int i = 0; i < SHA256_DIGEST_SIZE; i++)
 835		sprintf(&outbuf[i * 2], "%02x", sha256buf[i]);
 836	outbuf[SHA256_BLOCK_SIZE] = 0;
 837	dev_dbg(device, "Loaded FW: %s, sha256: %s\n", name, outbuf);
 838
 839out_shash:
 840	crypto_free_shash(alg);
 841out_free:
 842	kfree(shash);
 843	kfree(outbuf);
 844	kfree(sha256buf);
 845}
 846#else
 847static void fw_log_firmware_info(const struct firmware *fw, const char *name,
 848				 struct device *device)
 849{}
 850#endif
 851
 852/* called from request_firmware() and request_firmware_work_func() */
 853static int
 854_request_firmware(const struct firmware **firmware_p, const char *name,
 855		  struct device *device, void *buf, size_t size,
 856		  size_t offset, u32 opt_flags)
 857{
 858	struct firmware *fw = NULL;
 859	struct cred *kern_cred = NULL;
 860	const struct cred *old_cred;
 861	bool nondirect = false;
 862	int ret;
 863
 864	if (!firmware_p)
 865		return -EINVAL;
 866
 867	if (!name || name[0] == '\0') {
 868		ret = -EINVAL;
 869		goto out;
 870	}
 871
 872	ret = _request_firmware_prepare(&fw, name, device, buf, size,
 873					offset, opt_flags);
 874	if (ret <= 0) /* error or already assigned */
 875		goto out;
 876
 877	/*
 878	 * We are about to try to access the firmware file. Because we may have been
 879	 * called by a driver when serving an unrelated request from userland, we use
 880	 * the kernel credentials to read the file.
 881	 */
 882	kern_cred = prepare_kernel_cred(&init_task);
 883	if (!kern_cred) {
 884		ret = -ENOMEM;
 885		goto out;
 886	}
 887	old_cred = override_creds(kern_cred);
 888
 889	ret = fw_get_filesystem_firmware(device, fw->priv, "", NULL);
 890
 891	/* Only full reads can support decompression, platform, and sysfs. */
 892	if (!(opt_flags & FW_OPT_PARTIAL))
 893		nondirect = true;
 894
 895#ifdef CONFIG_FW_LOADER_COMPRESS_ZSTD
 896	if (ret == -ENOENT && nondirect)
 897		ret = fw_get_filesystem_firmware(device, fw->priv, ".zst",
 898						 fw_decompress_zstd);
 899#endif
 900#ifdef CONFIG_FW_LOADER_COMPRESS_XZ
 901	if (ret == -ENOENT && nondirect)
 902		ret = fw_get_filesystem_firmware(device, fw->priv, ".xz",
 903						 fw_decompress_xz);
 904#endif
 905	if (ret == -ENOENT && nondirect)
 906		ret = firmware_fallback_platform(fw->priv);
 907
 908	if (ret) {
 909		if (!(opt_flags & FW_OPT_NO_WARN))
 910			dev_warn(device,
 911				 "Direct firmware load for %s failed with error %d\n",
 912				 name, ret);
 913		if (nondirect)
 914			ret = firmware_fallback_sysfs(fw, name, device,
 915						      opt_flags, ret);
 916	} else
 917		ret = assign_fw(fw, device);
 918
 919	revert_creds(old_cred);
 920	put_cred(kern_cred);
 921
 922out:
 923	if (ret < 0) {
 924		fw_abort_batch_reqs(fw);
 925		release_firmware(fw);
 926		fw = NULL;
 927	} else {
 928		fw_log_firmware_info(fw, name, device);
 929	}
 930
 931	*firmware_p = fw;
 932	return ret;
 933}
 934
 935/**
 936 * request_firmware() - send firmware request and wait for it
 937 * @firmware_p: pointer to firmware image
 938 * @name: name of firmware file
 939 * @device: device for which firmware is being loaded
 940 *
 941 *      @firmware_p will be used to return a firmware image by the name
 942 *      of @name for device @device.
 943 *
 944 *      Should be called from user context where sleeping is allowed.
 945 *
 946 *      @name will be used as $FIRMWARE in the uevent environment and
 947 *      should be distinctive enough not to be confused with any other
 948 *      firmware image for this or any other device.
 949 *
 950 *	Caller must hold the reference count of @device.
 951 *
 952 *	The function can be called safely inside device's suspend and
 953 *	resume callback.
 954 **/
 955int
 956request_firmware(const struct firmware **firmware_p, const char *name,
 957		 struct device *device)
 958{
 959	int ret;
 960
 961	/* Need to pin this module until return */
 962	__module_get(THIS_MODULE);
 963	ret = _request_firmware(firmware_p, name, device, NULL, 0, 0,
 964				FW_OPT_UEVENT);
 965	module_put(THIS_MODULE);
 966	return ret;
 967}
 968EXPORT_SYMBOL(request_firmware);
 969
 970/**
 971 * firmware_request_nowarn() - request for an optional fw module
 972 * @firmware: pointer to firmware image
 973 * @name: name of firmware file
 974 * @device: device for which firmware is being loaded
 975 *
 976 * This function is similar in behaviour to request_firmware(), except it
 977 * doesn't produce warning messages when the file is not found. The sysfs
 978 * fallback mechanism is enabled if direct filesystem lookup fails. However,
 979 * failures to find the firmware file with it are still suppressed. It is
 980 * therefore up to the driver to check for the return value of this call and to
 981 * decide when to inform the users of errors.
 982 **/
 983int firmware_request_nowarn(const struct firmware **firmware, const char *name,
 984			    struct device *device)
 985{
 986	int ret;
 987
 988	/* Need to pin this module until return */
 989	__module_get(THIS_MODULE);
 990	ret = _request_firmware(firmware, name, device, NULL, 0, 0,
 991				FW_OPT_UEVENT | FW_OPT_NO_WARN);
 992	module_put(THIS_MODULE);
 993	return ret;
 994}
 995EXPORT_SYMBOL_GPL(firmware_request_nowarn);
 996
 997/**
 998 * request_firmware_direct() - load firmware directly without usermode helper
 999 * @firmware_p: pointer to firmware image
1000 * @name: name of firmware file
1001 * @device: device for which firmware is being loaded
1002 *
1003 * This function works pretty much like request_firmware(), but this doesn't
1004 * fall back to usermode helper even if the firmware couldn't be loaded
1005 * directly from fs.  Hence it's useful for loading optional firmwares, which
1006 * aren't always present, without extra long timeouts of udev.
1007 **/
1008int request_firmware_direct(const struct firmware **firmware_p,
1009			    const char *name, struct device *device)
1010{
1011	int ret;
1012
1013	__module_get(THIS_MODULE);
1014	ret = _request_firmware(firmware_p, name, device, NULL, 0, 0,
1015				FW_OPT_UEVENT | FW_OPT_NO_WARN |
1016				FW_OPT_NOFALLBACK_SYSFS);
1017	module_put(THIS_MODULE);
1018	return ret;
1019}
1020EXPORT_SYMBOL_GPL(request_firmware_direct);
1021
1022/**
1023 * firmware_request_platform() - request firmware with platform-fw fallback
1024 * @firmware: pointer to firmware image
1025 * @name: name of firmware file
1026 * @device: device for which firmware is being loaded
1027 *
1028 * This function is similar in behaviour to request_firmware, except that if
1029 * direct filesystem lookup fails, it will fallback to looking for a copy of the
1030 * requested firmware embedded in the platform's main (e.g. UEFI) firmware.
1031 **/
1032int firmware_request_platform(const struct firmware **firmware,
1033			      const char *name, struct device *device)
1034{
1035	int ret;
1036
1037	/* Need to pin this module until return */
1038	__module_get(THIS_MODULE);
1039	ret = _request_firmware(firmware, name, device, NULL, 0, 0,
1040				FW_OPT_UEVENT | FW_OPT_FALLBACK_PLATFORM);
1041	module_put(THIS_MODULE);
1042	return ret;
1043}
1044EXPORT_SYMBOL_GPL(firmware_request_platform);
1045
1046/**
1047 * firmware_request_cache() - cache firmware for suspend so resume can use it
1048 * @name: name of firmware file
1049 * @device: device for which firmware should be cached for
1050 *
1051 * There are some devices with an optimization that enables the device to not
1052 * require loading firmware on system reboot. This optimization may still
1053 * require the firmware present on resume from suspend. This routine can be
1054 * used to ensure the firmware is present on resume from suspend in these
1055 * situations. This helper is not compatible with drivers which use
1056 * request_firmware_into_buf() or request_firmware_nowait() with no uevent set.
1057 **/
1058int firmware_request_cache(struct device *device, const char *name)
1059{
1060	int ret;
1061
1062	mutex_lock(&fw_lock);
1063	ret = fw_add_devm_name(device, name);
1064	mutex_unlock(&fw_lock);
1065
1066	return ret;
1067}
1068EXPORT_SYMBOL_GPL(firmware_request_cache);
1069
1070/**
1071 * request_firmware_into_buf() - load firmware into a previously allocated buffer
1072 * @firmware_p: pointer to firmware image
1073 * @name: name of firmware file
1074 * @device: device for which firmware is being loaded and DMA region allocated
1075 * @buf: address of buffer to load firmware into
1076 * @size: size of buffer
1077 *
1078 * This function works pretty much like request_firmware(), but it doesn't
1079 * allocate a buffer to hold the firmware data. Instead, the firmware
1080 * is loaded directly into the buffer pointed to by @buf and the @firmware_p
1081 * data member is pointed at @buf.
1082 *
1083 * This function doesn't cache firmware either.
1084 */
1085int
1086request_firmware_into_buf(const struct firmware **firmware_p, const char *name,
1087			  struct device *device, void *buf, size_t size)
1088{
1089	int ret;
1090
1091	if (fw_cache_is_setup(device, name))
1092		return -EOPNOTSUPP;
1093
1094	__module_get(THIS_MODULE);
1095	ret = _request_firmware(firmware_p, name, device, buf, size, 0,
1096				FW_OPT_UEVENT | FW_OPT_NOCACHE);
1097	module_put(THIS_MODULE);
1098	return ret;
1099}
1100EXPORT_SYMBOL(request_firmware_into_buf);
1101
1102/**
1103 * request_partial_firmware_into_buf() - load partial firmware into a previously allocated buffer
1104 * @firmware_p: pointer to firmware image
1105 * @name: name of firmware file
1106 * @device: device for which firmware is being loaded and DMA region allocated
1107 * @buf: address of buffer to load firmware into
1108 * @size: size of buffer
1109 * @offset: offset into file to read
1110 *
1111 * This function works pretty much like request_firmware_into_buf except
1112 * it allows a partial read of the file.
1113 */
1114int
1115request_partial_firmware_into_buf(const struct firmware **firmware_p,
1116				  const char *name, struct device *device,
1117				  void *buf, size_t size, size_t offset)
1118{
1119	int ret;
1120
1121	if (fw_cache_is_setup(device, name))
1122		return -EOPNOTSUPP;
1123
1124	__module_get(THIS_MODULE);
1125	ret = _request_firmware(firmware_p, name, device, buf, size, offset,
1126				FW_OPT_UEVENT | FW_OPT_NOCACHE |
1127				FW_OPT_PARTIAL);
1128	module_put(THIS_MODULE);
1129	return ret;
1130}
1131EXPORT_SYMBOL(request_partial_firmware_into_buf);
1132
1133/**
1134 * release_firmware() - release the resource associated with a firmware image
1135 * @fw: firmware resource to release
1136 **/
1137void release_firmware(const struct firmware *fw)
1138{
1139	if (fw) {
1140		if (!firmware_is_builtin(fw))
1141			firmware_free_data(fw);
1142		kfree(fw);
1143	}
1144}
1145EXPORT_SYMBOL(release_firmware);
1146
1147/* Async support */
1148struct firmware_work {
1149	struct work_struct work;
1150	struct module *module;
1151	const char *name;
1152	struct device *device;
1153	void *context;
1154	void (*cont)(const struct firmware *fw, void *context);
1155	u32 opt_flags;
1156};
1157
1158static void request_firmware_work_func(struct work_struct *work)
1159{
1160	struct firmware_work *fw_work;
1161	const struct firmware *fw;
1162
1163	fw_work = container_of(work, struct firmware_work, work);
1164
1165	_request_firmware(&fw, fw_work->name, fw_work->device, NULL, 0, 0,
1166			  fw_work->opt_flags);
1167	fw_work->cont(fw, fw_work->context);
1168	put_device(fw_work->device); /* taken in request_firmware_nowait() */
1169
1170	module_put(fw_work->module);
1171	kfree_const(fw_work->name);
1172	kfree(fw_work);
1173}
1174
1175/**
1176 * request_firmware_nowait() - asynchronous version of request_firmware
1177 * @module: module requesting the firmware
1178 * @uevent: sends uevent to copy the firmware image if this flag
1179 *	is non-zero else the firmware copy must be done manually.
1180 * @name: name of firmware file
1181 * @device: device for which firmware is being loaded
1182 * @gfp: allocation flags
1183 * @context: will be passed over to @cont, and
1184 *	@fw may be %NULL if firmware request fails.
1185 * @cont: function will be called asynchronously when the firmware
1186 *	request is over.
1187 *
1188 *	Caller must hold the reference count of @device.
1189 *
1190 *	Asynchronous variant of request_firmware() for user contexts:
1191 *		- sleep for as small periods as possible since it may
1192 *		  increase kernel boot time of built-in device drivers
1193 *		  requesting firmware in their ->probe() methods, if
1194 *		  @gfp is GFP_KERNEL.
1195 *
1196 *		- can't sleep at all if @gfp is GFP_ATOMIC.
1197 **/
1198int
1199request_firmware_nowait(
1200	struct module *module, bool uevent,
1201	const char *name, struct device *device, gfp_t gfp, void *context,
1202	void (*cont)(const struct firmware *fw, void *context))
1203{
1204	struct firmware_work *fw_work;
1205
1206	fw_work = kzalloc(sizeof(struct firmware_work), gfp);
1207	if (!fw_work)
1208		return -ENOMEM;
1209
1210	fw_work->module = module;
1211	fw_work->name = kstrdup_const(name, gfp);
1212	if (!fw_work->name) {
1213		kfree(fw_work);
1214		return -ENOMEM;
1215	}
1216	fw_work->device = device;
1217	fw_work->context = context;
1218	fw_work->cont = cont;
1219	fw_work->opt_flags = FW_OPT_NOWAIT |
1220		(uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER);
1221
1222	if (!uevent && fw_cache_is_setup(device, name)) {
1223		kfree_const(fw_work->name);
1224		kfree(fw_work);
1225		return -EOPNOTSUPP;
1226	}
1227
1228	if (!try_module_get(module)) {
1229		kfree_const(fw_work->name);
1230		kfree(fw_work);
1231		return -EFAULT;
1232	}
1233
1234	get_device(fw_work->device);
1235	INIT_WORK(&fw_work->work, request_firmware_work_func);
1236	schedule_work(&fw_work->work);
1237	return 0;
1238}
1239EXPORT_SYMBOL(request_firmware_nowait);
1240
1241#ifdef CONFIG_FW_CACHE
1242static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
1243
1244/**
1245 * cache_firmware() - cache one firmware image in kernel memory space
1246 * @fw_name: the firmware image name
1247 *
1248 * Cache firmware in kernel memory so that drivers can use it when
1249 * system isn't ready for them to request firmware image from userspace.
1250 * Once it returns successfully, driver can use request_firmware or its
1251 * nowait version to get the cached firmware without any interacting
1252 * with userspace
1253 *
1254 * Return 0 if the firmware image has been cached successfully
1255 * Return !0 otherwise
1256 *
1257 */
1258static int cache_firmware(const char *fw_name)
1259{
1260	int ret;
1261	const struct firmware *fw;
1262
1263	pr_debug("%s: %s\n", __func__, fw_name);
1264
1265	ret = request_firmware(&fw, fw_name, NULL);
1266	if (!ret)
1267		kfree(fw);
1268
1269	pr_debug("%s: %s ret=%d\n", __func__, fw_name, ret);
1270
1271	return ret;
1272}
1273
1274static struct fw_priv *lookup_fw_priv(const char *fw_name)
1275{
1276	struct fw_priv *tmp;
1277	struct firmware_cache *fwc = &fw_cache;
1278
1279	spin_lock(&fwc->lock);
1280	tmp = __lookup_fw_priv(fw_name);
1281	spin_unlock(&fwc->lock);
1282
1283	return tmp;
1284}
1285
1286/**
1287 * uncache_firmware() - remove one cached firmware image
1288 * @fw_name: the firmware image name
1289 *
1290 * Uncache one firmware image which has been cached successfully
1291 * before.
1292 *
1293 * Return 0 if the firmware cache has been removed successfully
1294 * Return !0 otherwise
1295 *
1296 */
1297static int uncache_firmware(const char *fw_name)
1298{
1299	struct fw_priv *fw_priv;
1300	struct firmware fw;
1301
1302	pr_debug("%s: %s\n", __func__, fw_name);
1303
1304	if (firmware_request_builtin(&fw, fw_name))
1305		return 0;
1306
1307	fw_priv = lookup_fw_priv(fw_name);
1308	if (fw_priv) {
1309		free_fw_priv(fw_priv);
1310		return 0;
1311	}
1312
1313	return -EINVAL;
1314}
1315
1316static struct fw_cache_entry *alloc_fw_cache_entry(const char *name)
1317{
1318	struct fw_cache_entry *fce;
1319
1320	fce = kzalloc(sizeof(*fce), GFP_ATOMIC);
1321	if (!fce)
1322		goto exit;
1323
1324	fce->name = kstrdup_const(name, GFP_ATOMIC);
1325	if (!fce->name) {
1326		kfree(fce);
1327		fce = NULL;
1328		goto exit;
1329	}
1330exit:
1331	return fce;
1332}
1333
1334static int __fw_entry_found(const char *name)
1335{
1336	struct firmware_cache *fwc = &fw_cache;
1337	struct fw_cache_entry *fce;
1338
1339	list_for_each_entry(fce, &fwc->fw_names, list) {
1340		if (!strcmp(fce->name, name))
1341			return 1;
1342	}
1343	return 0;
1344}
1345
1346static void fw_cache_piggyback_on_request(struct fw_priv *fw_priv)
1347{
1348	const char *name = fw_priv->fw_name;
1349	struct firmware_cache *fwc = fw_priv->fwc;
1350	struct fw_cache_entry *fce;
1351
1352	spin_lock(&fwc->name_lock);
1353	if (__fw_entry_found(name))
1354		goto found;
1355
1356	fce = alloc_fw_cache_entry(name);
1357	if (fce) {
1358		list_add(&fce->list, &fwc->fw_names);
1359		kref_get(&fw_priv->ref);
1360		pr_debug("%s: fw: %s\n", __func__, name);
1361	}
1362found:
1363	spin_unlock(&fwc->name_lock);
1364}
1365
1366static void free_fw_cache_entry(struct fw_cache_entry *fce)
1367{
1368	kfree_const(fce->name);
1369	kfree(fce);
1370}
1371
1372static void __async_dev_cache_fw_image(void *fw_entry,
1373				       async_cookie_t cookie)
1374{
1375	struct fw_cache_entry *fce = fw_entry;
1376	struct firmware_cache *fwc = &fw_cache;
1377	int ret;
1378
1379	ret = cache_firmware(fce->name);
1380	if (ret) {
1381		spin_lock(&fwc->name_lock);
1382		list_del(&fce->list);
1383		spin_unlock(&fwc->name_lock);
1384
1385		free_fw_cache_entry(fce);
1386	}
1387}
1388
1389/* called with dev->devres_lock held */
1390static void dev_create_fw_entry(struct device *dev, void *res,
1391				void *data)
1392{
1393	struct fw_name_devm *fwn = res;
1394	const char *fw_name = fwn->name;
1395	struct list_head *head = data;
1396	struct fw_cache_entry *fce;
1397
1398	fce = alloc_fw_cache_entry(fw_name);
1399	if (fce)
1400		list_add(&fce->list, head);
1401}
1402
1403static int devm_name_match(struct device *dev, void *res,
1404			   void *match_data)
1405{
1406	struct fw_name_devm *fwn = res;
1407	return (fwn->magic == (unsigned long)match_data);
1408}
1409
1410static void dev_cache_fw_image(struct device *dev, void *data)
1411{
1412	LIST_HEAD(todo);
1413	struct fw_cache_entry *fce;
1414	struct fw_cache_entry *fce_next;
1415	struct firmware_cache *fwc = &fw_cache;
1416
1417	devres_for_each_res(dev, fw_name_devm_release,
1418			    devm_name_match, &fw_cache,
1419			    dev_create_fw_entry, &todo);
1420
1421	list_for_each_entry_safe(fce, fce_next, &todo, list) {
1422		list_del(&fce->list);
1423
1424		spin_lock(&fwc->name_lock);
1425		/* only one cache entry for one firmware */
1426		if (!__fw_entry_found(fce->name)) {
1427			list_add(&fce->list, &fwc->fw_names);
1428		} else {
1429			free_fw_cache_entry(fce);
1430			fce = NULL;
1431		}
1432		spin_unlock(&fwc->name_lock);
1433
1434		if (fce)
1435			async_schedule_domain(__async_dev_cache_fw_image,
1436					      (void *)fce,
1437					      &fw_cache_domain);
1438	}
1439}
1440
1441static void __device_uncache_fw_images(void)
1442{
1443	struct firmware_cache *fwc = &fw_cache;
1444	struct fw_cache_entry *fce;
1445
1446	spin_lock(&fwc->name_lock);
1447	while (!list_empty(&fwc->fw_names)) {
1448		fce = list_entry(fwc->fw_names.next,
1449				struct fw_cache_entry, list);
1450		list_del(&fce->list);
1451		spin_unlock(&fwc->name_lock);
1452
1453		uncache_firmware(fce->name);
1454		free_fw_cache_entry(fce);
1455
1456		spin_lock(&fwc->name_lock);
1457	}
1458	spin_unlock(&fwc->name_lock);
1459}
1460
1461/**
1462 * device_cache_fw_images() - cache devices' firmware
1463 *
1464 * If one device called request_firmware or its nowait version
1465 * successfully before, the firmware names are recored into the
1466 * device's devres link list, so device_cache_fw_images can call
1467 * cache_firmware() to cache these firmwares for the device,
1468 * then the device driver can load its firmwares easily at
1469 * time when system is not ready to complete loading firmware.
1470 */
1471static void device_cache_fw_images(void)
1472{
1473	struct firmware_cache *fwc = &fw_cache;
1474	DEFINE_WAIT(wait);
1475
1476	pr_debug("%s\n", __func__);
1477
1478	/* cancel uncache work */
1479	cancel_delayed_work_sync(&fwc->work);
1480
1481	fw_fallback_set_cache_timeout();
1482
1483	mutex_lock(&fw_lock);
1484	fwc->state = FW_LOADER_START_CACHE;
1485	dpm_for_each_dev(NULL, dev_cache_fw_image);
1486	mutex_unlock(&fw_lock);
1487
1488	/* wait for completion of caching firmware for all devices */
1489	async_synchronize_full_domain(&fw_cache_domain);
1490
1491	fw_fallback_set_default_timeout();
1492}
1493
1494/**
1495 * device_uncache_fw_images() - uncache devices' firmware
1496 *
1497 * uncache all firmwares which have been cached successfully
1498 * by device_uncache_fw_images earlier
1499 */
1500static void device_uncache_fw_images(void)
1501{
1502	pr_debug("%s\n", __func__);
1503	__device_uncache_fw_images();
1504}
1505
1506static void device_uncache_fw_images_work(struct work_struct *work)
1507{
1508	device_uncache_fw_images();
1509}
1510
1511/**
1512 * device_uncache_fw_images_delay() - uncache devices firmwares
1513 * @delay: number of milliseconds to delay uncache device firmwares
1514 *
1515 * uncache all devices's firmwares which has been cached successfully
1516 * by device_cache_fw_images after @delay milliseconds.
1517 */
1518static void device_uncache_fw_images_delay(unsigned long delay)
1519{
1520	queue_delayed_work(system_power_efficient_wq, &fw_cache.work,
1521			   msecs_to_jiffies(delay));
1522}
1523
1524static int fw_pm_notify(struct notifier_block *notify_block,
1525			unsigned long mode, void *unused)
1526{
1527	switch (mode) {
1528	case PM_HIBERNATION_PREPARE:
1529	case PM_SUSPEND_PREPARE:
1530	case PM_RESTORE_PREPARE:
1531		/*
1532		 * Here, kill pending fallback requests will only kill
1533		 * non-uevent firmware request to avoid stalling suspend.
1534		 */
1535		kill_pending_fw_fallback_reqs(false);
1536		device_cache_fw_images();
1537		break;
1538
1539	case PM_POST_SUSPEND:
1540	case PM_POST_HIBERNATION:
1541	case PM_POST_RESTORE:
1542		/*
1543		 * In case that system sleep failed and syscore_suspend is
1544		 * not called.
1545		 */
1546		mutex_lock(&fw_lock);
1547		fw_cache.state = FW_LOADER_NO_CACHE;
1548		mutex_unlock(&fw_lock);
1549
1550		device_uncache_fw_images_delay(10 * MSEC_PER_SEC);
1551		break;
1552	}
1553
1554	return 0;
1555}
1556
1557/* stop caching firmware once syscore_suspend is reached */
1558static int fw_suspend(void)
1559{
1560	fw_cache.state = FW_LOADER_NO_CACHE;
1561	return 0;
1562}
1563
1564static struct syscore_ops fw_syscore_ops = {
1565	.suspend = fw_suspend,
1566};
1567
1568static int __init register_fw_pm_ops(void)
1569{
1570	int ret;
1571
1572	spin_lock_init(&fw_cache.name_lock);
1573	INIT_LIST_HEAD(&fw_cache.fw_names);
1574
1575	INIT_DELAYED_WORK(&fw_cache.work,
1576			  device_uncache_fw_images_work);
1577
1578	fw_cache.pm_notify.notifier_call = fw_pm_notify;
1579	ret = register_pm_notifier(&fw_cache.pm_notify);
1580	if (ret)
1581		return ret;
1582
1583	register_syscore_ops(&fw_syscore_ops);
1584
1585	return ret;
1586}
1587
1588static inline void unregister_fw_pm_ops(void)
1589{
1590	unregister_syscore_ops(&fw_syscore_ops);
1591	unregister_pm_notifier(&fw_cache.pm_notify);
1592}
1593#else
1594static void fw_cache_piggyback_on_request(struct fw_priv *fw_priv)
1595{
1596}
1597static inline int register_fw_pm_ops(void)
1598{
1599	return 0;
1600}
1601static inline void unregister_fw_pm_ops(void)
1602{
1603}
1604#endif
1605
1606static void __init fw_cache_init(void)
1607{
1608	spin_lock_init(&fw_cache.lock);
1609	INIT_LIST_HEAD(&fw_cache.head);
1610	fw_cache.state = FW_LOADER_NO_CACHE;
1611}
1612
1613static int fw_shutdown_notify(struct notifier_block *unused1,
1614			      unsigned long unused2, void *unused3)
1615{
1616	/*
1617	 * Kill all pending fallback requests to avoid both stalling shutdown,
1618	 * and avoid a deadlock with the usermode_lock.
1619	 */
1620	kill_pending_fw_fallback_reqs(true);
1621
1622	return NOTIFY_DONE;
1623}
1624
1625static struct notifier_block fw_shutdown_nb = {
1626	.notifier_call = fw_shutdown_notify,
1627};
1628
1629static int __init firmware_class_init(void)
1630{
1631	int ret;
1632
1633	/* No need to unfold these on exit */
1634	fw_cache_init();
1635
1636	ret = register_fw_pm_ops();
1637	if (ret)
1638		return ret;
1639
1640	ret = register_reboot_notifier(&fw_shutdown_nb);
1641	if (ret)
1642		goto out;
1643
1644	return register_sysfs_loader();
1645
1646out:
1647	unregister_fw_pm_ops();
1648	return ret;
1649}
1650
1651static void __exit firmware_class_exit(void)
1652{
1653	unregister_fw_pm_ops();
1654	unregister_reboot_notifier(&fw_shutdown_nb);
1655	unregister_sysfs_loader();
1656}
1657
1658fs_initcall(firmware_class_init);
1659module_exit(firmware_class_exit);