main.c

   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/sha2.h>
 810
 811static void fw_log_firmware_info(const struct firmware *fw, const char *name, struct device *device)
 812{
 813	u8 digest[SHA256_DIGEST_SIZE];
 814
 815	sha256(fw->data, fw->size, digest);
 816	dev_dbg(device, "Loaded FW: %s, sha256: %*phN\n",
 817		name, SHA256_DIGEST_SIZE, digest);
 818}
 819#else
 820static void fw_log_firmware_info(const struct firmware *fw, const char *name,
 821				 struct device *device)
 822{}
 823#endif
 824
 825/* called from request_firmware() and request_firmware_work_func() */
 826static int
 827_request_firmware(const struct firmware **firmware_p, const char *name,
 828		  struct device *device, void *buf, size_t size,
 829		  size_t offset, u32 opt_flags)
 830{
 831	struct firmware *fw = NULL;
 832	bool nondirect = false;
 833	int ret;
 834
 835	if (!firmware_p)
 836		return -EINVAL;
 837
 838	if (!name || name[0] == '\0') {
 839		ret = -EINVAL;
 840		goto out;
 841	}
 842
 843
 844	/*
 845	 * Reject firmware file names with ".." path components.
 846	 * There are drivers that construct firmware file names from
 847	 * device-supplied strings, and we don't want some device to be
 848	 * able to tell us "I would like to be sent my firmware from
 849	 * ../../../etc/shadow, please".
 850	 *
 851	 * This intentionally only looks at the firmware name, not at
 852	 * the firmware base directory or at symlink contents.
 853	 */
 854	if (name_contains_dotdot(name)) {
 855		dev_warn(device,
 856			 "Firmware load for '%s' refused, path contains '..' component\n",
 857			 name);
 858		ret = -EINVAL;
 859		goto out;
 860	}
 861
 862	ret = _request_firmware_prepare(&fw, name, device, buf, size,
 863					offset, opt_flags);
 864	if (ret <= 0) /* error or already assigned */
 865		goto out;
 866
 867	/*
 868	 * We are about to try to access the firmware file. Because we may have been
 869	 * called by a driver when serving an unrelated request from userland, we use
 870	 * the kernel credentials to read the file.
 871	 */
 872	scoped_with_kernel_creds() {
 873		ret = fw_get_filesystem_firmware(device, fw->priv, "", NULL);
 874
 875		/* Only full reads can support decompression, platform, and sysfs. */
 876		if (!(opt_flags & FW_OPT_PARTIAL))
 877			nondirect = true;
 878
 879#ifdef CONFIG_FW_LOADER_COMPRESS_ZSTD
 880		if (ret == -ENOENT && nondirect)
 881			ret = fw_get_filesystem_firmware(device, fw->priv, ".zst",
 882							 fw_decompress_zstd);
 883#endif
 884#ifdef CONFIG_FW_LOADER_COMPRESS_XZ
 885		if (ret == -ENOENT && nondirect)
 886			ret = fw_get_filesystem_firmware(device, fw->priv, ".xz",
 887							 fw_decompress_xz);
 888#endif
 889		if (ret == -ENOENT && nondirect)
 890			ret = firmware_fallback_platform(fw->priv);
 891
 892		if (ret) {
 893			if (!(opt_flags & FW_OPT_NO_WARN))
 894				dev_warn(device,
 895					 "Direct firmware load for %s failed with error %d\n",
 896					 name, ret);
 897			if (nondirect)
 898				ret = firmware_fallback_sysfs(fw, name, device,
 899							      opt_flags, ret);
 900		} else {
 901			ret = assign_fw(fw, device);
 902		}
 903	}
 904
 905out:
 906	if (ret < 0) {
 907		fw_abort_batch_reqs(fw);
 908		release_firmware(fw);
 909		fw = NULL;
 910	} else {
 911		fw_log_firmware_info(fw, name, device);
 912	}
 913
 914	*firmware_p = fw;
 915	return ret;
 916}
 917
 918/**
 919 * request_firmware() - send firmware request and wait for it
 920 * @firmware_p: pointer to firmware image
 921 * @name: name of firmware file
 922 * @device: device for which firmware is being loaded
 923 *
 924 *      @firmware_p will be used to return a firmware image by the name
 925 *      of @name for device @device.
 926 *
 927 *      Should be called from user context where sleeping is allowed.
 928 *
 929 *      @name will be used as $FIRMWARE in the uevent environment and
 930 *      should be distinctive enough not to be confused with any other
 931 *      firmware image for this or any other device.
 932 *	It must not contain any ".." path components - "foo/bar..bin" is
 933 *	allowed, but "foo/../bar.bin" is not.
 934 *
 935 *	Caller must hold the reference count of @device.
 936 *
 937 *	The function can be called safely inside device's suspend and
 938 *	resume callback.
 939 **/
 940int
 941request_firmware(const struct firmware **firmware_p, const char *name,
 942		 struct device *device)
 943{
 944	int ret;
 945
 946	/* Need to pin this module until return */
 947	__module_get(THIS_MODULE);
 948	ret = _request_firmware(firmware_p, name, device, NULL, 0, 0,
 949				FW_OPT_UEVENT);
 950	module_put(THIS_MODULE);
 951	return ret;
 952}
 953EXPORT_SYMBOL(request_firmware);
 954
 955/**
 956 * firmware_request_nowarn() - request for an optional fw module
 957 * @firmware: pointer to firmware image
 958 * @name: name of firmware file
 959 * @device: device for which firmware is being loaded
 960 *
 961 * This function is similar in behaviour to request_firmware(), except it
 962 * doesn't produce warning messages when the file is not found. The sysfs
 963 * fallback mechanism is enabled if direct filesystem lookup fails. However,
 964 * failures to find the firmware file with it are still suppressed. It is
 965 * therefore up to the driver to check for the return value of this call and to
 966 * decide when to inform the users of errors.
 967 **/
 968int firmware_request_nowarn(const struct firmware **firmware, const char *name,
 969			    struct device *device)
 970{
 971	int ret;
 972
 973	/* Need to pin this module until return */
 974	__module_get(THIS_MODULE);
 975	ret = _request_firmware(firmware, name, device, NULL, 0, 0,
 976				FW_OPT_UEVENT | FW_OPT_NO_WARN);
 977	module_put(THIS_MODULE);
 978	return ret;
 979}
 980EXPORT_SYMBOL_GPL(firmware_request_nowarn);
 981
 982/**
 983 * request_firmware_direct() - load firmware directly without usermode helper
 984 * @firmware_p: pointer to firmware image
 985 * @name: name of firmware file
 986 * @device: device for which firmware is being loaded
 987 *
 988 * This function works pretty much like request_firmware(), but this doesn't
 989 * fall back to usermode helper even if the firmware couldn't be loaded
 990 * directly from fs.  Hence it's useful for loading optional firmwares, which
 991 * aren't always present, without extra long timeouts of udev.
 992 **/
 993int request_firmware_direct(const struct firmware **firmware_p,
 994			    const char *name, struct device *device)
 995{
 996	int ret;
 997
 998	__module_get(THIS_MODULE);
 999	ret = _request_firmware(firmware_p, name, device, NULL, 0, 0,
1000				FW_OPT_UEVENT | FW_OPT_NO_WARN |
1001				FW_OPT_NOFALLBACK_SYSFS);
1002	module_put(THIS_MODULE);
1003	return ret;
1004}
1005EXPORT_SYMBOL_GPL(request_firmware_direct);
1006
1007/**
1008 * firmware_request_platform() - request firmware with platform-fw fallback
1009 * @firmware: pointer to firmware image
1010 * @name: name of firmware file
1011 * @device: device for which firmware is being loaded
1012 *
1013 * This function is similar in behaviour to request_firmware, except that if
1014 * direct filesystem lookup fails, it will fallback to looking for a copy of the
1015 * requested firmware embedded in the platform's main (e.g. UEFI) firmware.
1016 **/
1017int firmware_request_platform(const struct firmware **firmware,
1018			      const char *name, struct device *device)
1019{
1020	int ret;
1021
1022	/* Need to pin this module until return */
1023	__module_get(THIS_MODULE);
1024	ret = _request_firmware(firmware, name, device, NULL, 0, 0,
1025				FW_OPT_UEVENT | FW_OPT_FALLBACK_PLATFORM);
1026	module_put(THIS_MODULE);
1027	return ret;
1028}
1029EXPORT_SYMBOL_GPL(firmware_request_platform);
1030
1031/**
1032 * firmware_request_cache() - cache firmware for suspend so resume can use it
1033 * @device: device for which firmware should be cached for
1034 * @name: name of firmware file
1035 *
1036 * There are some devices with an optimization that enables the device to not
1037 * require loading firmware on system reboot. This optimization may still
1038 * require the firmware present on resume from suspend. This routine can be
1039 * used to ensure the firmware is present on resume from suspend in these
1040 * situations. This helper is not compatible with drivers which use
1041 * request_firmware_into_buf() or request_firmware_nowait() with no uevent set.
1042 **/
1043int firmware_request_cache(struct device *device, const char *name)
1044{
1045	int ret;
1046
1047	mutex_lock(&fw_lock);
1048	ret = fw_add_devm_name(device, name);
1049	mutex_unlock(&fw_lock);
1050
1051	return ret;
1052}
1053EXPORT_SYMBOL_GPL(firmware_request_cache);
1054
1055/**
1056 * request_firmware_into_buf() - load firmware into a previously allocated buffer
1057 * @firmware_p: pointer to firmware image
1058 * @name: name of firmware file
1059 * @device: device for which firmware is being loaded and DMA region allocated
1060 * @buf: address of buffer to load firmware into
1061 * @size: size of buffer
1062 *
1063 * This function works pretty much like request_firmware(), but it doesn't
1064 * allocate a buffer to hold the firmware data. Instead, the firmware
1065 * is loaded directly into the buffer pointed to by @buf and the @firmware_p
1066 * data member is pointed at @buf.
1067 *
1068 * This function doesn't cache firmware either.
1069 */
1070int
1071request_firmware_into_buf(const struct firmware **firmware_p, const char *name,
1072			  struct device *device, void *buf, size_t size)
1073{
1074	int ret;
1075
1076	if (fw_cache_is_setup(device, name))
1077		return -EOPNOTSUPP;
1078
1079	__module_get(THIS_MODULE);
1080	ret = _request_firmware(firmware_p, name, device, buf, size, 0,
1081				FW_OPT_UEVENT | FW_OPT_NOCACHE);
1082	module_put(THIS_MODULE);
1083	return ret;
1084}
1085EXPORT_SYMBOL(request_firmware_into_buf);
1086
1087/**
1088 * request_partial_firmware_into_buf() - load partial firmware into a previously allocated buffer
1089 * @firmware_p: pointer to firmware image
1090 * @name: name of firmware file
1091 * @device: device for which firmware is being loaded and DMA region allocated
1092 * @buf: address of buffer to load firmware into
1093 * @size: size of buffer
1094 * @offset: offset into file to read
1095 *
1096 * This function works pretty much like request_firmware_into_buf except
1097 * it allows a partial read of the file.
1098 */
1099int
1100request_partial_firmware_into_buf(const struct firmware **firmware_p,
1101				  const char *name, struct device *device,
1102				  void *buf, size_t size, size_t offset)
1103{
1104	int ret;
1105
1106	if (fw_cache_is_setup(device, name))
1107		return -EOPNOTSUPP;
1108
1109	__module_get(THIS_MODULE);
1110	ret = _request_firmware(firmware_p, name, device, buf, size, offset,
1111				FW_OPT_UEVENT | FW_OPT_NOCACHE |
1112				FW_OPT_PARTIAL);
1113	module_put(THIS_MODULE);
1114	return ret;
1115}
1116EXPORT_SYMBOL(request_partial_firmware_into_buf);
1117
1118/**
1119 * release_firmware() - release the resource associated with a firmware image
1120 * @fw: firmware resource to release
1121 **/
1122void release_firmware(const struct firmware *fw)
1123{
1124	if (fw) {
1125		if (!firmware_is_builtin(fw))
1126			firmware_free_data(fw);
1127		kfree(fw);
1128	}
1129}
1130EXPORT_SYMBOL(release_firmware);
1131
1132/* Async support */
1133struct firmware_work {
1134	struct work_struct work;
1135	struct module *module;
1136	const char *name;
1137	struct device *device;
1138	void *context;
1139	void (*cont)(const struct firmware *fw, void *context);
1140	u32 opt_flags;
1141};
1142
1143static void request_firmware_work_func(struct work_struct *work)
1144{
1145	struct firmware_work *fw_work;
1146	const struct firmware *fw;
1147
1148	fw_work = container_of(work, struct firmware_work, work);
1149
1150	_request_firmware(&fw, fw_work->name, fw_work->device, NULL, 0, 0,
1151			  fw_work->opt_flags);
1152	fw_work->cont(fw, fw_work->context);
1153	put_device(fw_work->device); /* taken in request_firmware_nowait() */
1154
1155	module_put(fw_work->module);
1156	kfree_const(fw_work->name);
1157	kfree(fw_work);
1158}
1159
1160
1161static int _request_firmware_nowait(
1162	struct module *module, bool uevent,
1163	const char *name, struct device *device, gfp_t gfp, void *context,
1164	void (*cont)(const struct firmware *fw, void *context), bool nowarn)
1165{
1166	struct firmware_work *fw_work;
1167
1168	fw_work = kzalloc(sizeof(struct firmware_work), gfp);
1169	if (!fw_work)
1170		return -ENOMEM;
1171
1172	fw_work->module = module;
1173	fw_work->name = kstrdup_const(name, gfp);
1174	if (!fw_work->name) {
1175		kfree(fw_work);
1176		return -ENOMEM;
1177	}
1178	fw_work->device = device;
1179	fw_work->context = context;
1180	fw_work->cont = cont;
1181	fw_work->opt_flags = FW_OPT_NOWAIT |
1182		(uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER) |
1183		(nowarn ? FW_OPT_NO_WARN : 0);
1184
1185	if (!uevent && fw_cache_is_setup(device, name)) {
1186		kfree_const(fw_work->name);
1187		kfree(fw_work);
1188		return -EOPNOTSUPP;
1189	}
1190
1191	if (!try_module_get(module)) {
1192		kfree_const(fw_work->name);
1193		kfree(fw_work);
1194		return -EFAULT;
1195	}
1196
1197	get_device(fw_work->device);
1198	INIT_WORK(&fw_work->work, request_firmware_work_func);
1199	schedule_work(&fw_work->work);
1200	return 0;
1201}
1202
1203/**
1204 * request_firmware_nowait() - asynchronous version of request_firmware
1205 * @module: module requesting the firmware
1206 * @uevent: sends uevent to copy the firmware image if this flag
1207 *	is non-zero else the firmware copy must be done manually.
1208 * @name: name of firmware file
1209 * @device: device for which firmware is being loaded
1210 * @gfp: allocation flags
1211 * @context: will be passed over to @cont, and
1212 *	@fw may be %NULL if firmware request fails.
1213 * @cont: function will be called asynchronously when the firmware
1214 *	request is over.
1215 *
1216 *	Caller must hold the reference count of @device.
1217 *
1218 *	Asynchronous variant of request_firmware() for user contexts:
1219 *		- sleep for as small periods as possible since it may
1220 *		  increase kernel boot time of built-in device drivers
1221 *		  requesting firmware in their ->probe() methods, if
1222 *		  @gfp is GFP_KERNEL.
1223 *
1224 *		- can't sleep at all if @gfp is GFP_ATOMIC.
1225 **/
1226int request_firmware_nowait(
1227	struct module *module, bool uevent,
1228	const char *name, struct device *device, gfp_t gfp, void *context,
1229	void (*cont)(const struct firmware *fw, void *context))
1230{
1231	return _request_firmware_nowait(module, uevent, name, device, gfp,
1232					context, cont, false);
1233
1234}
1235EXPORT_SYMBOL(request_firmware_nowait);
1236
1237/**
1238 * firmware_request_nowait_nowarn() - async version of request_firmware_nowarn
1239 * @module: module requesting the firmware
1240 * @name: name of firmware file
1241 * @device: device for which firmware is being loaded
1242 * @gfp: allocation flags
1243 * @context: will be passed over to @cont, and
1244 *	@fw may be %NULL if firmware request fails.
1245 * @cont: function will be called asynchronously when the firmware
1246 *	request is over.
1247 *
1248 * Similar in function to request_firmware_nowait(), but doesn't print a warning
1249 * when the firmware file could not be found and always sends a uevent to copy
1250 * the firmware image.
1251 */
1252int firmware_request_nowait_nowarn(
1253	struct module *module, const char *name,
1254	struct device *device, gfp_t gfp, void *context,
1255	void (*cont)(const struct firmware *fw, void *context))
1256{
1257	return _request_firmware_nowait(module, FW_ACTION_UEVENT, name, device,
1258					gfp, context, cont, true);
1259}
1260EXPORT_SYMBOL_GPL(firmware_request_nowait_nowarn);
1261
1262#ifdef CONFIG_FW_CACHE
1263static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
1264
1265/**
1266 * cache_firmware() - cache one firmware image in kernel memory space
1267 * @fw_name: the firmware image name
1268 *
1269 * Cache firmware in kernel memory so that drivers can use it when
1270 * system isn't ready for them to request firmware image from userspace.
1271 * Once it returns successfully, driver can use request_firmware or its
1272 * nowait version to get the cached firmware without any interacting
1273 * with userspace
1274 *
1275 * Return 0 if the firmware image has been cached successfully
1276 * Return !0 otherwise
1277 *
1278 */
1279static int cache_firmware(const char *fw_name)
1280{
1281	int ret;
1282	const struct firmware *fw;
1283
1284	pr_debug("%s: %s\n", __func__, fw_name);
1285
1286	ret = request_firmware(&fw, fw_name, NULL);
1287	if (!ret)
1288		kfree(fw);
1289
1290	pr_debug("%s: %s ret=%d\n", __func__, fw_name, ret);
1291
1292	return ret;
1293}
1294
1295static struct fw_priv *lookup_fw_priv(const char *fw_name)
1296{
1297	struct fw_priv *tmp;
1298	struct firmware_cache *fwc = &fw_cache;
1299
1300	spin_lock(&fwc->lock);
1301	tmp = __lookup_fw_priv(fw_name);
1302	spin_unlock(&fwc->lock);
1303
1304	return tmp;
1305}
1306
1307/**
1308 * uncache_firmware() - remove one cached firmware image
1309 * @fw_name: the firmware image name
1310 *
1311 * Uncache one firmware image which has been cached successfully
1312 * before.
1313 *
1314 * Return 0 if the firmware cache has been removed successfully
1315 * Return !0 otherwise
1316 *
1317 */
1318static int uncache_firmware(const char *fw_name)
1319{
1320	struct fw_priv *fw_priv;
1321	struct firmware fw;
1322
1323	pr_debug("%s: %s\n", __func__, fw_name);
1324
1325	if (firmware_request_builtin(&fw, fw_name))
1326		return 0;
1327
1328	fw_priv = lookup_fw_priv(fw_name);
1329	if (fw_priv) {
1330		free_fw_priv(fw_priv);
1331		return 0;
1332	}
1333
1334	return -EINVAL;
1335}
1336
1337static struct fw_cache_entry *alloc_fw_cache_entry(const char *name)
1338{
1339	struct fw_cache_entry *fce;
1340
1341	fce = kzalloc(sizeof(*fce), GFP_ATOMIC);
1342	if (!fce)
1343		goto exit;
1344
1345	fce->name = kstrdup_const(name, GFP_ATOMIC);
1346	if (!fce->name) {
1347		kfree(fce);
1348		fce = NULL;
1349		goto exit;
1350	}
1351exit:
1352	return fce;
1353}
1354
1355static int __fw_entry_found(const char *name)
1356{
1357	struct firmware_cache *fwc = &fw_cache;
1358	struct fw_cache_entry *fce;
1359
1360	list_for_each_entry(fce, &fwc->fw_names, list) {
1361		if (!strcmp(fce->name, name))
1362			return 1;
1363	}
1364	return 0;
1365}
1366
1367static void fw_cache_piggyback_on_request(struct fw_priv *fw_priv)
1368{
1369	const char *name = fw_priv->fw_name;
1370	struct firmware_cache *fwc = fw_priv->fwc;
1371	struct fw_cache_entry *fce;
1372
1373	spin_lock(&fwc->name_lock);
1374	if (__fw_entry_found(name))
1375		goto found;
1376
1377	fce = alloc_fw_cache_entry(name);
1378	if (fce) {
1379		list_add(&fce->list, &fwc->fw_names);
1380		kref_get(&fw_priv->ref);
1381		pr_debug("%s: fw: %s\n", __func__, name);
1382	}
1383found:
1384	spin_unlock(&fwc->name_lock);
1385}
1386
1387static void free_fw_cache_entry(struct fw_cache_entry *fce)
1388{
1389	kfree_const(fce->name);
1390	kfree(fce);
1391}
1392
1393static void __async_dev_cache_fw_image(void *fw_entry,
1394				       async_cookie_t cookie)
1395{
1396	struct fw_cache_entry *fce = fw_entry;
1397	struct firmware_cache *fwc = &fw_cache;
1398	int ret;
1399
1400	ret = cache_firmware(fce->name);
1401	if (ret) {
1402		spin_lock(&fwc->name_lock);
1403		list_del(&fce->list);
1404		spin_unlock(&fwc->name_lock);
1405
1406		free_fw_cache_entry(fce);
1407	}
1408}
1409
1410/* called with dev->devres_lock held */
1411static void dev_create_fw_entry(struct device *dev, void *res,
1412				void *data)
1413{
1414	struct fw_name_devm *fwn = res;
1415	const char *fw_name = fwn->name;
1416	struct list_head *head = data;
1417	struct fw_cache_entry *fce;
1418
1419	fce = alloc_fw_cache_entry(fw_name);
1420	if (fce)
1421		list_add(&fce->list, head);
1422}
1423
1424static int devm_name_match(struct device *dev, void *res,
1425			   void *match_data)
1426{
1427	struct fw_name_devm *fwn = res;
1428	return (fwn->magic == (unsigned long)match_data);
1429}
1430
1431static void dev_cache_fw_image(struct device *dev, void *data)
1432{
1433	LIST_HEAD(todo);
1434	struct fw_cache_entry *fce;
1435	struct fw_cache_entry *fce_next;
1436	struct firmware_cache *fwc = &fw_cache;
1437
1438	devres_for_each_res(dev, fw_name_devm_release,
1439			    devm_name_match, &fw_cache,
1440			    dev_create_fw_entry, &todo);
1441
1442	list_for_each_entry_safe(fce, fce_next, &todo, list) {
1443		list_del(&fce->list);
1444
1445		spin_lock(&fwc->name_lock);
1446		/* only one cache entry for one firmware */
1447		if (!__fw_entry_found(fce->name)) {
1448			list_add(&fce->list, &fwc->fw_names);
1449		} else {
1450			free_fw_cache_entry(fce);
1451			fce = NULL;
1452		}
1453		spin_unlock(&fwc->name_lock);
1454
1455		if (fce)
1456			async_schedule_domain(__async_dev_cache_fw_image,
1457					      (void *)fce,
1458					      &fw_cache_domain);
1459	}
1460}
1461
1462static void __device_uncache_fw_images(void)
1463{
1464	struct firmware_cache *fwc = &fw_cache;
1465	struct fw_cache_entry *fce;
1466
1467	spin_lock(&fwc->name_lock);
1468	while (!list_empty(&fwc->fw_names)) {
1469		fce = list_entry(fwc->fw_names.next,
1470				struct fw_cache_entry, list);
1471		list_del(&fce->list);
1472		spin_unlock(&fwc->name_lock);
1473
1474		uncache_firmware(fce->name);
1475		free_fw_cache_entry(fce);
1476
1477		spin_lock(&fwc->name_lock);
1478	}
1479	spin_unlock(&fwc->name_lock);
1480}
1481
1482/**
1483 * device_cache_fw_images() - cache devices' firmware
1484 *
1485 * If one device called request_firmware or its nowait version
1486 * successfully before, the firmware names are recored into the
1487 * device's devres link list, so device_cache_fw_images can call
1488 * cache_firmware() to cache these firmwares for the device,
1489 * then the device driver can load its firmwares easily at
1490 * time when system is not ready to complete loading firmware.
1491 */
1492static void device_cache_fw_images(void)
1493{
1494	struct firmware_cache *fwc = &fw_cache;
1495	DEFINE_WAIT(wait);
1496
1497	pr_debug("%s\n", __func__);
1498
1499	/* cancel uncache work */
1500	cancel_delayed_work_sync(&fwc->work);
1501
1502	fw_fallback_set_cache_timeout();
1503
1504	mutex_lock(&fw_lock);
1505	fwc->state = FW_LOADER_START_CACHE;
1506	dpm_for_each_dev(NULL, dev_cache_fw_image);
1507	mutex_unlock(&fw_lock);
1508
1509	/* wait for completion of caching firmware for all devices */
1510	async_synchronize_full_domain(&fw_cache_domain);
1511
1512	fw_fallback_set_default_timeout();
1513}
1514
1515/**
1516 * device_uncache_fw_images() - uncache devices' firmware
1517 *
1518 * uncache all firmwares which have been cached successfully
1519 * by device_uncache_fw_images earlier
1520 */
1521static void device_uncache_fw_images(void)
1522{
1523	pr_debug("%s\n", __func__);
1524	__device_uncache_fw_images();
1525}
1526
1527static void device_uncache_fw_images_work(struct work_struct *work)
1528{
1529	device_uncache_fw_images();
1530}
1531
1532/**
1533 * device_uncache_fw_images_delay() - uncache devices firmwares
1534 * @delay: number of milliseconds to delay uncache device firmwares
1535 *
1536 * uncache all devices's firmwares which has been cached successfully
1537 * by device_cache_fw_images after @delay milliseconds.
1538 */
1539static void device_uncache_fw_images_delay(unsigned long delay)
1540{
1541	queue_delayed_work(system_power_efficient_wq, &fw_cache.work,
1542			   msecs_to_jiffies(delay));
1543}
1544
1545static int fw_pm_notify(struct notifier_block *notify_block,
1546			unsigned long mode, void *unused)
1547{
1548	switch (mode) {
1549	case PM_HIBERNATION_PREPARE:
1550	case PM_SUSPEND_PREPARE:
1551	case PM_RESTORE_PREPARE:
1552		/*
1553		 * Here, kill pending fallback requests will only kill
1554		 * non-uevent firmware request to avoid stalling suspend.
1555		 */
1556		kill_pending_fw_fallback_reqs(false);
1557		device_cache_fw_images();
1558		break;
1559
1560	case PM_POST_SUSPEND:
1561	case PM_POST_HIBERNATION:
1562	case PM_POST_RESTORE:
1563		/*
1564		 * In case that system sleep failed and syscore_suspend is
1565		 * not called.
1566		 */
1567		mutex_lock(&fw_lock);
1568		fw_cache.state = FW_LOADER_NO_CACHE;
1569		mutex_unlock(&fw_lock);
1570
1571		device_uncache_fw_images_delay(10 * MSEC_PER_SEC);
1572		break;
1573	}
1574
1575	return 0;
1576}
1577
1578/* stop caching firmware once syscore_suspend is reached */
1579static int fw_suspend(void *data)
1580{
1581	fw_cache.state = FW_LOADER_NO_CACHE;
1582	return 0;
1583}
1584
1585static const struct syscore_ops fw_syscore_ops = {
1586	.suspend = fw_suspend,
1587};
1588
1589static struct syscore fw_syscore = {
1590	.ops = &fw_syscore_ops,
1591};
1592
1593static int __init register_fw_pm_ops(void)
1594{
1595	int ret;
1596
1597	spin_lock_init(&fw_cache.name_lock);
1598	INIT_LIST_HEAD(&fw_cache.fw_names);
1599
1600	INIT_DELAYED_WORK(&fw_cache.work,
1601			  device_uncache_fw_images_work);
1602
1603	fw_cache.pm_notify.notifier_call = fw_pm_notify;
1604	ret = register_pm_notifier(&fw_cache.pm_notify);
1605	if (ret)
1606		return ret;
1607
1608	register_syscore(&fw_syscore);
1609
1610	return ret;
1611}
1612
1613static inline void unregister_fw_pm_ops(void)
1614{
1615	unregister_syscore(&fw_syscore);
1616	unregister_pm_notifier(&fw_cache.pm_notify);
1617}
1618#else
1619static void fw_cache_piggyback_on_request(struct fw_priv *fw_priv)
1620{
1621}
1622static inline int register_fw_pm_ops(void)
1623{
1624	return 0;
1625}
1626static inline void unregister_fw_pm_ops(void)
1627{
1628}
1629#endif
1630
1631static void __init fw_cache_init(void)
1632{
1633	spin_lock_init(&fw_cache.lock);
1634	INIT_LIST_HEAD(&fw_cache.head);
1635	fw_cache.state = FW_LOADER_NO_CACHE;
1636}
1637
1638static int fw_shutdown_notify(struct notifier_block *unused1,
1639			      unsigned long unused2, void *unused3)
1640{
1641	/*
1642	 * Kill all pending fallback requests to avoid both stalling shutdown,
1643	 * and avoid a deadlock with the usermode_lock.
1644	 */
1645	kill_pending_fw_fallback_reqs(true);
1646
1647	return NOTIFY_DONE;
1648}
1649
1650static struct notifier_block fw_shutdown_nb = {
1651	.notifier_call = fw_shutdown_notify,
1652};
1653
1654static int __init firmware_class_init(void)
1655{
1656	int ret;
1657
1658	/* No need to unfold these on exit */
1659	fw_cache_init();
1660
1661	ret = register_fw_pm_ops();
1662	if (ret)
1663		return ret;
1664
1665	ret = register_reboot_notifier(&fw_shutdown_nb);
1666	if (ret)
1667		goto out;
1668
1669	return register_sysfs_loader();
1670
1671out:
1672	unregister_fw_pm_ops();
1673	return ret;
1674}
1675
1676static void __exit firmware_class_exit(void)
1677{
1678	unregister_fw_pm_ops();
1679	unregister_reboot_notifier(&fw_shutdown_nb);
1680	unregister_sysfs_loader();
1681}
1682
1683fs_initcall(firmware_class_init);
1684module_exit(firmware_class_exit);