1 // SPDX-License-Identifier: GPL-2.0
3 * main.c - Multi purpose firmware loading support
5 * Copyright (c) 2003 Manuel Estrada Sainz
7 * Please see Documentation/driver-api/firmware/ for more information.
11 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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>
32 #include <linux/async.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>
41 #include <generated/utsrelease.h>
47 MODULE_AUTHOR("Manuel Estrada Sainz");
48 MODULE_DESCRIPTION("Multi purpose firmware loading support");
49 MODULE_LICENSE("GPL");
51 struct firmware_cache {
52 /* firmware_buf instance will be added into the below list */
54 struct list_head head;
57 #ifdef CONFIG_FW_CACHE
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
65 struct list_head fw_names;
67 struct delayed_work work;
69 struct notifier_block pm_notify;
73 struct fw_cache_entry {
74 struct list_head list;
83 static inline struct fw_priv *to_fw_priv(struct kref *ref)
85 return container_of(ref, struct fw_priv, ref);
88 #define FW_LOADER_NO_CACHE 0
89 #define FW_LOADER_START_CACHE 1
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 */
93 DEFINE_MUTEX(fw_lock);
95 struct firmware_cache fw_cache;
97 void fw_state_init(struct fw_priv *fw_priv)
99 struct fw_state *fw_st = &fw_priv->fw_st;
101 init_completion(&fw_st->completion);
102 fw_st->status = FW_STATUS_UNKNOWN;
105 static inline int fw_state_wait(struct fw_priv *fw_priv)
107 return __fw_state_wait_common(fw_priv, MAX_SCHEDULE_TIMEOUT);
110 static void fw_cache_piggyback_on_request(struct fw_priv *fw_priv);
112 static struct fw_priv *__allocate_fw_priv(const char *fw_name,
113 struct firmware_cache *fwc,
119 struct fw_priv *fw_priv;
121 /* For a partial read, the buffer must be preallocated. */
122 if ((opt_flags & FW_OPT_PARTIAL) && !dbuf)
125 /* Only partial reads are allowed to use an offset. */
126 if (offset != 0 && !(opt_flags & FW_OPT_PARTIAL))
129 fw_priv = kzalloc(sizeof(*fw_priv), GFP_ATOMIC);
133 fw_priv->fw_name = kstrdup_const(fw_name, GFP_ATOMIC);
134 if (!fw_priv->fw_name) {
139 kref_init(&fw_priv->ref);
141 fw_priv->data = dbuf;
142 fw_priv->allocated_size = size;
143 fw_priv->offset = offset;
144 fw_priv->opt_flags = opt_flags;
145 fw_state_init(fw_priv);
146 #ifdef CONFIG_FW_LOADER_USER_HELPER
147 INIT_LIST_HEAD(&fw_priv->pending_list);
150 pr_debug("%s: fw-%s fw_priv=%p\n", __func__, fw_name, fw_priv);
155 static struct fw_priv *__lookup_fw_priv(const char *fw_name)
158 struct firmware_cache *fwc = &fw_cache;
160 list_for_each_entry(tmp, &fwc->head, list)
161 if (!strcmp(tmp->fw_name, fw_name))
166 /* Returns 1 for batching firmware requests with the same name */
167 int alloc_lookup_fw_priv(const char *fw_name, struct firmware_cache *fwc,
168 struct fw_priv **fw_priv, void *dbuf, size_t size,
169 size_t offset, u32 opt_flags)
173 spin_lock(&fwc->lock);
175 * Do not merge requests that are marked to be non-cached or
176 * are performing partial reads.
178 if (!(opt_flags & (FW_OPT_NOCACHE | FW_OPT_PARTIAL))) {
179 tmp = __lookup_fw_priv(fw_name);
182 spin_unlock(&fwc->lock);
184 pr_debug("batched request - sharing the same struct fw_priv and lookup for multiple requests\n");
189 tmp = __allocate_fw_priv(fw_name, fwc, dbuf, size, offset, opt_flags);
191 INIT_LIST_HEAD(&tmp->list);
192 if (!(opt_flags & FW_OPT_NOCACHE))
193 list_add(&tmp->list, &fwc->head);
195 spin_unlock(&fwc->lock);
199 return tmp ? 0 : -ENOMEM;
202 static void __free_fw_priv(struct kref *ref)
203 __releases(&fwc->lock)
205 struct fw_priv *fw_priv = to_fw_priv(ref);
206 struct firmware_cache *fwc = fw_priv->fwc;
208 pr_debug("%s: fw-%s fw_priv=%p data=%p size=%u\n",
209 __func__, fw_priv->fw_name, fw_priv, fw_priv->data,
210 (unsigned int)fw_priv->size);
212 list_del(&fw_priv->list);
213 spin_unlock(&fwc->lock);
215 if (fw_is_paged_buf(fw_priv))
216 fw_free_paged_buf(fw_priv);
217 else if (!fw_priv->allocated_size)
218 vfree(fw_priv->data);
220 kfree_const(fw_priv->fw_name);
224 void free_fw_priv(struct fw_priv *fw_priv)
226 struct firmware_cache *fwc = fw_priv->fwc;
227 spin_lock(&fwc->lock);
228 if (!kref_put(&fw_priv->ref, __free_fw_priv))
229 spin_unlock(&fwc->lock);
232 #ifdef CONFIG_FW_LOADER_PAGED_BUF
233 bool fw_is_paged_buf(struct fw_priv *fw_priv)
235 return fw_priv->is_paged_buf;
238 void fw_free_paged_buf(struct fw_priv *fw_priv)
245 vunmap(fw_priv->data);
247 for (i = 0; i < fw_priv->nr_pages; i++)
248 __free_page(fw_priv->pages[i]);
249 kvfree(fw_priv->pages);
250 fw_priv->pages = NULL;
251 fw_priv->page_array_size = 0;
252 fw_priv->nr_pages = 0;
253 fw_priv->data = NULL;
257 int fw_grow_paged_buf(struct fw_priv *fw_priv, int pages_needed)
259 /* If the array of pages is too small, grow it */
260 if (fw_priv->page_array_size < pages_needed) {
261 int new_array_size = max(pages_needed,
262 fw_priv->page_array_size * 2);
263 struct page **new_pages;
265 new_pages = kvmalloc_array(new_array_size, sizeof(void *),
269 memcpy(new_pages, fw_priv->pages,
270 fw_priv->page_array_size * sizeof(void *));
271 memset(&new_pages[fw_priv->page_array_size], 0, sizeof(void *) *
272 (new_array_size - fw_priv->page_array_size));
273 kvfree(fw_priv->pages);
274 fw_priv->pages = new_pages;
275 fw_priv->page_array_size = new_array_size;
278 while (fw_priv->nr_pages < pages_needed) {
279 fw_priv->pages[fw_priv->nr_pages] =
280 alloc_page(GFP_KERNEL | __GFP_HIGHMEM);
282 if (!fw_priv->pages[fw_priv->nr_pages])
290 int fw_map_paged_buf(struct fw_priv *fw_priv)
292 /* one pages buffer should be mapped/unmapped only once */
296 vunmap(fw_priv->data);
297 fw_priv->data = vmap(fw_priv->pages, fw_priv->nr_pages, 0,
307 * ZSTD-compressed firmware support
309 #ifdef CONFIG_FW_LOADER_COMPRESS_ZSTD
310 static int fw_decompress_zstd(struct device *dev, struct fw_priv *fw_priv,
311 size_t in_size, const void *in_buffer)
313 size_t len, out_size, workspace_size;
314 void *workspace, *out_buf;
318 if (fw_priv->allocated_size) {
319 out_size = fw_priv->allocated_size;
320 out_buf = fw_priv->data;
322 zstd_frame_header params;
324 if (zstd_get_frame_header(¶ms, in_buffer, in_size) ||
325 params.frameContentSize == ZSTD_CONTENTSIZE_UNKNOWN) {
326 dev_dbg(dev, "%s: invalid zstd header\n", __func__);
329 out_size = params.frameContentSize;
330 out_buf = vzalloc(out_size);
335 workspace_size = zstd_dctx_workspace_bound();
336 workspace = kvzalloc(workspace_size, GFP_KERNEL);
342 ctx = zstd_init_dctx(workspace, workspace_size);
344 dev_dbg(dev, "%s: failed to initialize context\n", __func__);
349 len = zstd_decompress_dctx(ctx, out_buf, out_size, in_buffer, in_size);
350 if (zstd_is_error(len)) {
351 dev_dbg(dev, "%s: failed to decompress: %d\n", __func__,
352 zstd_get_error_code(len));
357 if (!fw_priv->allocated_size)
358 fw_priv->data = out_buf;
364 if (err && !fw_priv->allocated_size)
368 #endif /* CONFIG_FW_LOADER_COMPRESS_ZSTD */
371 * XZ-compressed firmware support
373 #ifdef CONFIG_FW_LOADER_COMPRESS_XZ
374 /* show an error and return the standard error code */
375 static int fw_decompress_xz_error(struct device *dev, enum xz_ret xz_ret)
377 if (xz_ret != XZ_STREAM_END) {
378 dev_warn(dev, "xz decompression failed (xz_ret=%d)\n", xz_ret);
379 return xz_ret == XZ_MEM_ERROR ? -ENOMEM : -EINVAL;
384 /* single-shot decompression onto the pre-allocated buffer */
385 static int fw_decompress_xz_single(struct device *dev, struct fw_priv *fw_priv,
386 size_t in_size, const void *in_buffer)
388 struct xz_dec *xz_dec;
389 struct xz_buf xz_buf;
392 xz_dec = xz_dec_init(XZ_SINGLE, (u32)-1);
396 xz_buf.in_size = in_size;
397 xz_buf.in = in_buffer;
399 xz_buf.out_size = fw_priv->allocated_size;
400 xz_buf.out = fw_priv->data;
403 xz_ret = xz_dec_run(xz_dec, &xz_buf);
406 fw_priv->size = xz_buf.out_pos;
407 return fw_decompress_xz_error(dev, xz_ret);
410 /* decompression on paged buffer and map it */
411 static int fw_decompress_xz_pages(struct device *dev, struct fw_priv *fw_priv,
412 size_t in_size, const void *in_buffer)
414 struct xz_dec *xz_dec;
415 struct xz_buf xz_buf;
420 xz_dec = xz_dec_init(XZ_DYNALLOC, (u32)-1);
424 xz_buf.in_size = in_size;
425 xz_buf.in = in_buffer;
428 fw_priv->is_paged_buf = true;
431 if (fw_grow_paged_buf(fw_priv, fw_priv->nr_pages + 1)) {
436 /* decompress onto the new allocated page */
437 page = fw_priv->pages[fw_priv->nr_pages - 1];
438 xz_buf.out = kmap_local_page(page);
440 xz_buf.out_size = PAGE_SIZE;
441 xz_ret = xz_dec_run(xz_dec, &xz_buf);
442 kunmap_local(xz_buf.out);
443 fw_priv->size += xz_buf.out_pos;
444 /* partial decompression means either end or error */
445 if (xz_buf.out_pos != PAGE_SIZE)
447 } while (xz_ret == XZ_OK);
449 err = fw_decompress_xz_error(dev, xz_ret);
451 err = fw_map_paged_buf(fw_priv);
458 static int fw_decompress_xz(struct device *dev, struct fw_priv *fw_priv,
459 size_t in_size, const void *in_buffer)
461 /* if the buffer is pre-allocated, we can perform in single-shot mode */
463 return fw_decompress_xz_single(dev, fw_priv, in_size, in_buffer);
465 return fw_decompress_xz_pages(dev, fw_priv, in_size, in_buffer);
467 #endif /* CONFIG_FW_LOADER_COMPRESS_XZ */
469 /* direct firmware loading support */
470 static char fw_path_para[256];
471 static const char * const fw_path[] = {
473 "/lib/firmware/updates/" UTS_RELEASE,
474 "/lib/firmware/updates",
475 "/lib/firmware/" UTS_RELEASE,
480 * Typical usage is that passing 'firmware_class.path=$CUSTOMIZED_PATH'
481 * from kernel command line because firmware_class is generally built in
482 * kernel instead of module.
484 module_param_string(path, fw_path_para, sizeof(fw_path_para), 0644);
485 MODULE_PARM_DESC(path, "customized firmware image search path with a higher priority than default path");
488 fw_get_filesystem_firmware(struct device *device, struct fw_priv *fw_priv,
490 int (*decompress)(struct device *dev,
491 struct fw_priv *fw_priv,
493 const void *in_buffer))
496 int i, len, maxlen = 0;
498 char *path, *nt = NULL;
499 size_t msize = INT_MAX;
502 /* Already populated data member means we're loading into a buffer */
503 if (!decompress && fw_priv->data) {
504 buffer = fw_priv->data;
505 msize = fw_priv->allocated_size;
512 wait_for_initramfs();
513 for (i = 0; i < ARRAY_SIZE(fw_path); i++) {
514 size_t file_size = 0;
515 size_t *file_size_ptr = NULL;
517 /* skip the unset customized path */
521 /* strip off \n from customized path */
522 maxlen = strlen(fw_path[i]);
524 nt = strchr(fw_path[i], '\n');
526 maxlen = nt - fw_path[i];
529 len = snprintf(path, PATH_MAX, "%.*s/%s%s",
531 fw_priv->fw_name, suffix);
532 if (len >= PATH_MAX) {
540 * The total file size is only examined when doing a partial
541 * read; the "full read" case needs to fail if the whole
542 * firmware was not completely loaded.
544 if ((fw_priv->opt_flags & FW_OPT_PARTIAL) && buffer)
545 file_size_ptr = &file_size;
547 /* load firmware files from the mount namespace of init */
548 rc = kernel_read_file_from_path_initns(path, fw_priv->offset,
554 dev_warn(device, "loading %s failed with error %d\n",
557 dev_dbg(device, "loading %s failed for no such file or directory.\n",
564 dev_dbg(device, "Loading firmware from %s\n", path);
566 dev_dbg(device, "f/w decompressing %s\n",
568 rc = decompress(device, fw_priv, size, buffer);
569 /* discard the superfluous original content */
573 fw_free_paged_buf(fw_priv);
577 dev_dbg(device, "direct-loading %s\n",
580 fw_priv->data = buffer;
581 fw_priv->size = size;
583 fw_state_done(fw_priv);
591 /* firmware holds the ownership of pages */
592 static void firmware_free_data(const struct firmware *fw)
594 /* Loaded directly? */
599 free_fw_priv(fw->priv);
602 /* store the pages buffer info firmware from buf */
603 static void fw_set_page_data(struct fw_priv *fw_priv, struct firmware *fw)
606 fw->size = fw_priv->size;
607 fw->data = fw_priv->data;
609 pr_debug("%s: fw-%s fw_priv=%p data=%p size=%u\n",
610 __func__, fw_priv->fw_name, fw_priv, fw_priv->data,
611 (unsigned int)fw_priv->size);
614 #ifdef CONFIG_FW_CACHE
615 static void fw_name_devm_release(struct device *dev, void *res)
617 struct fw_name_devm *fwn = res;
619 if (fwn->magic == (unsigned long)&fw_cache)
620 pr_debug("%s: fw_name-%s devm-%p released\n",
621 __func__, fwn->name, res);
622 kfree_const(fwn->name);
625 static int fw_devm_match(struct device *dev, void *res,
628 struct fw_name_devm *fwn = res;
630 return (fwn->magic == (unsigned long)&fw_cache) &&
631 !strcmp(fwn->name, match_data);
634 static struct fw_name_devm *fw_find_devm_name(struct device *dev,
637 struct fw_name_devm *fwn;
639 fwn = devres_find(dev, fw_name_devm_release,
640 fw_devm_match, (void *)name);
644 static bool fw_cache_is_setup(struct device *dev, const char *name)
646 struct fw_name_devm *fwn;
648 fwn = fw_find_devm_name(dev, name);
655 /* add firmware name into devres list */
656 static int fw_add_devm_name(struct device *dev, const char *name)
658 struct fw_name_devm *fwn;
660 if (fw_cache_is_setup(dev, name))
663 fwn = devres_alloc(fw_name_devm_release, sizeof(struct fw_name_devm),
667 fwn->name = kstrdup_const(name, GFP_KERNEL);
673 fwn->magic = (unsigned long)&fw_cache;
674 devres_add(dev, fwn);
679 static bool fw_cache_is_setup(struct device *dev, const char *name)
684 static int fw_add_devm_name(struct device *dev, const char *name)
690 int assign_fw(struct firmware *fw, struct device *device)
692 struct fw_priv *fw_priv = fw->priv;
695 mutex_lock(&fw_lock);
696 if (!fw_priv->size || fw_state_is_aborted(fw_priv)) {
697 mutex_unlock(&fw_lock);
702 * add firmware name into devres list so that we can auto cache
703 * and uncache firmware for device.
705 * device may has been deleted already, but the problem
706 * should be fixed in devres or driver core.
708 /* don't cache firmware handled without uevent */
709 if (device && (fw_priv->opt_flags & FW_OPT_UEVENT) &&
710 !(fw_priv->opt_flags & FW_OPT_NOCACHE)) {
711 ret = fw_add_devm_name(device, fw_priv->fw_name);
713 mutex_unlock(&fw_lock);
719 * After caching firmware image is started, let it piggyback
720 * on request firmware.
722 if (!(fw_priv->opt_flags & FW_OPT_NOCACHE) &&
723 fw_priv->fwc->state == FW_LOADER_START_CACHE)
724 fw_cache_piggyback_on_request(fw_priv);
726 /* pass the pages buffer to driver at the last minute */
727 fw_set_page_data(fw_priv, fw);
728 mutex_unlock(&fw_lock);
732 /* prepare firmware and firmware_buf structs;
733 * return 0 if a firmware is already assigned, 1 if need to load one,
734 * or a negative error code
737 _request_firmware_prepare(struct firmware **firmware_p, const char *name,
738 struct device *device, void *dbuf, size_t size,
739 size_t offset, u32 opt_flags)
741 struct firmware *firmware;
742 struct fw_priv *fw_priv;
745 *firmware_p = firmware = kzalloc(sizeof(*firmware), GFP_KERNEL);
747 dev_err(device, "%s: kmalloc(struct firmware) failed\n",
752 if (firmware_request_builtin_buf(firmware, name, dbuf, size)) {
753 dev_dbg(device, "using built-in %s\n", name);
754 return 0; /* assigned */
757 ret = alloc_lookup_fw_priv(name, &fw_cache, &fw_priv, dbuf, size,
761 * bind with 'priv' now to avoid warning in failure path
762 * of requesting firmware.
764 firmware->priv = fw_priv;
767 ret = fw_state_wait(fw_priv);
769 fw_set_page_data(fw_priv, firmware);
770 return 0; /* assigned */
776 return 1; /* need to load */
780 * Batched requests need only one wake, we need to do this step last due to the
781 * fallback mechanism. The buf is protected with kref_get(), and it won't be
782 * released until the last user calls release_firmware().
784 * Failed batched requests are possible as well, in such cases we just share
785 * the struct fw_priv and won't release it until all requests are woken
786 * and have gone through this same path.
788 static void fw_abort_batch_reqs(struct firmware *fw)
790 struct fw_priv *fw_priv;
792 /* Loaded directly? */
793 if (!fw || !fw->priv)
797 mutex_lock(&fw_lock);
798 if (!fw_state_is_aborted(fw_priv))
799 fw_state_aborted(fw_priv);
800 mutex_unlock(&fw_lock);
803 #if defined(CONFIG_FW_LOADER_DEBUG)
804 #include <crypto/hash.h>
805 #include <crypto/sha2.h>
807 static void fw_log_firmware_info(const struct firmware *fw, const char *name, struct device *device)
809 struct shash_desc *shash;
810 struct crypto_shash *alg;
814 alg = crypto_alloc_shash("sha256", 0, 0);
818 sha256buf = kmalloc(SHA256_DIGEST_SIZE, GFP_KERNEL);
819 outbuf = kmalloc(SHA256_BLOCK_SIZE + 1, GFP_KERNEL);
820 shash = kmalloc(sizeof(*shash) + crypto_shash_descsize(alg), GFP_KERNEL);
821 if (!sha256buf || !outbuf || !shash)
826 if (crypto_shash_digest(shash, fw->data, fw->size, sha256buf) < 0)
829 for (int i = 0; i < SHA256_DIGEST_SIZE; i++)
830 sprintf(&outbuf[i * 2], "%02x", sha256buf[i]);
831 outbuf[SHA256_BLOCK_SIZE] = 0;
832 dev_dbg(device, "Loaded FW: %s, sha256: %s\n", name, outbuf);
835 crypto_free_shash(alg);
842 static void fw_log_firmware_info(const struct firmware *fw, const char *name,
843 struct device *device)
847 /* called from request_firmware() and request_firmware_work_func() */
849 _request_firmware(const struct firmware **firmware_p, const char *name,
850 struct device *device, void *buf, size_t size,
851 size_t offset, u32 opt_flags)
853 struct firmware *fw = NULL;
854 struct cred *kern_cred = NULL;
855 const struct cred *old_cred;
856 bool nondirect = false;
862 if (!name || name[0] == '\0') {
867 ret = _request_firmware_prepare(&fw, name, device, buf, size,
869 if (ret <= 0) /* error or already assigned */
873 * We are about to try to access the firmware file. Because we may have been
874 * called by a driver when serving an unrelated request from userland, we use
875 * the kernel credentials to read the file.
877 kern_cred = prepare_kernel_cred(&init_task);
882 old_cred = override_creds(kern_cred);
884 ret = fw_get_filesystem_firmware(device, fw->priv, "", NULL);
886 /* Only full reads can support decompression, platform, and sysfs. */
887 if (!(opt_flags & FW_OPT_PARTIAL))
890 #ifdef CONFIG_FW_LOADER_COMPRESS_ZSTD
891 if (ret == -ENOENT && nondirect)
892 ret = fw_get_filesystem_firmware(device, fw->priv, ".zst",
895 #ifdef CONFIG_FW_LOADER_COMPRESS_XZ
896 if (ret == -ENOENT && nondirect)
897 ret = fw_get_filesystem_firmware(device, fw->priv, ".xz",
900 if (ret == -ENOENT && nondirect)
901 ret = firmware_fallback_platform(fw->priv);
904 if (!(opt_flags & FW_OPT_NO_WARN))
906 "Direct firmware load for %s failed with error %d\n",
909 ret = firmware_fallback_sysfs(fw, name, device,
912 ret = assign_fw(fw, device);
914 revert_creds(old_cred);
919 fw_abort_batch_reqs(fw);
920 release_firmware(fw);
923 fw_log_firmware_info(fw, name, device);
931 * request_firmware() - send firmware request and wait for it
932 * @firmware_p: pointer to firmware image
933 * @name: name of firmware file
934 * @device: device for which firmware is being loaded
936 * @firmware_p will be used to return a firmware image by the name
937 * of @name for device @device.
939 * Should be called from user context where sleeping is allowed.
941 * @name will be used as $FIRMWARE in the uevent environment and
942 * should be distinctive enough not to be confused with any other
943 * firmware image for this or any other device.
945 * Caller must hold the reference count of @device.
947 * The function can be called safely inside device's suspend and
951 request_firmware(const struct firmware **firmware_p, const char *name,
952 struct device *device)
956 /* Need to pin this module until return */
957 __module_get(THIS_MODULE);
958 ret = _request_firmware(firmware_p, name, device, NULL, 0, 0,
960 module_put(THIS_MODULE);
963 EXPORT_SYMBOL(request_firmware);
966 * firmware_request_nowarn() - request for an optional fw module
967 * @firmware: pointer to firmware image
968 * @name: name of firmware file
969 * @device: device for which firmware is being loaded
971 * This function is similar in behaviour to request_firmware(), except it
972 * doesn't produce warning messages when the file is not found. The sysfs
973 * fallback mechanism is enabled if direct filesystem lookup fails. However,
974 * failures to find the firmware file with it are still suppressed. It is
975 * therefore up to the driver to check for the return value of this call and to
976 * decide when to inform the users of errors.
978 int firmware_request_nowarn(const struct firmware **firmware, const char *name,
979 struct device *device)
983 /* Need to pin this module until return */
984 __module_get(THIS_MODULE);
985 ret = _request_firmware(firmware, name, device, NULL, 0, 0,
986 FW_OPT_UEVENT | FW_OPT_NO_WARN);
987 module_put(THIS_MODULE);
990 EXPORT_SYMBOL_GPL(firmware_request_nowarn);
993 * request_firmware_direct() - load firmware directly without usermode helper
994 * @firmware_p: pointer to firmware image
995 * @name: name of firmware file
996 * @device: device for which firmware is being loaded
998 * This function works pretty much like request_firmware(), but this doesn't
999 * fall back to usermode helper even if the firmware couldn't be loaded
1000 * directly from fs. Hence it's useful for loading optional firmwares, which
1001 * aren't always present, without extra long timeouts of udev.
1003 int request_firmware_direct(const struct firmware **firmware_p,
1004 const char *name, struct device *device)
1008 __module_get(THIS_MODULE);
1009 ret = _request_firmware(firmware_p, name, device, NULL, 0, 0,
1010 FW_OPT_UEVENT | FW_OPT_NO_WARN |
1011 FW_OPT_NOFALLBACK_SYSFS);
1012 module_put(THIS_MODULE);
1015 EXPORT_SYMBOL_GPL(request_firmware_direct);
1018 * firmware_request_platform() - request firmware with platform-fw fallback
1019 * @firmware: pointer to firmware image
1020 * @name: name of firmware file
1021 * @device: device for which firmware is being loaded
1023 * This function is similar in behaviour to request_firmware, except that if
1024 * direct filesystem lookup fails, it will fallback to looking for a copy of the
1025 * requested firmware embedded in the platform's main (e.g. UEFI) firmware.
1027 int firmware_request_platform(const struct firmware **firmware,
1028 const char *name, struct device *device)
1032 /* Need to pin this module until return */
1033 __module_get(THIS_MODULE);
1034 ret = _request_firmware(firmware, name, device, NULL, 0, 0,
1035 FW_OPT_UEVENT | FW_OPT_FALLBACK_PLATFORM);
1036 module_put(THIS_MODULE);
1039 EXPORT_SYMBOL_GPL(firmware_request_platform);
1042 * firmware_request_cache() - cache firmware for suspend so resume can use it
1043 * @name: name of firmware file
1044 * @device: device for which firmware should be cached for
1046 * There are some devices with an optimization that enables the device to not
1047 * require loading firmware on system reboot. This optimization may still
1048 * require the firmware present on resume from suspend. This routine can be
1049 * used to ensure the firmware is present on resume from suspend in these
1050 * situations. This helper is not compatible with drivers which use
1051 * request_firmware_into_buf() or request_firmware_nowait() with no uevent set.
1053 int firmware_request_cache(struct device *device, const char *name)
1057 mutex_lock(&fw_lock);
1058 ret = fw_add_devm_name(device, name);
1059 mutex_unlock(&fw_lock);
1063 EXPORT_SYMBOL_GPL(firmware_request_cache);
1066 * request_firmware_into_buf() - load firmware into a previously allocated buffer
1067 * @firmware_p: pointer to firmware image
1068 * @name: name of firmware file
1069 * @device: device for which firmware is being loaded and DMA region allocated
1070 * @buf: address of buffer to load firmware into
1071 * @size: size of buffer
1073 * This function works pretty much like request_firmware(), but it doesn't
1074 * allocate a buffer to hold the firmware data. Instead, the firmware
1075 * is loaded directly into the buffer pointed to by @buf and the @firmware_p
1076 * data member is pointed at @buf.
1078 * This function doesn't cache firmware either.
1081 request_firmware_into_buf(const struct firmware **firmware_p, const char *name,
1082 struct device *device, void *buf, size_t size)
1086 if (fw_cache_is_setup(device, name))
1089 __module_get(THIS_MODULE);
1090 ret = _request_firmware(firmware_p, name, device, buf, size, 0,
1091 FW_OPT_UEVENT | FW_OPT_NOCACHE);
1092 module_put(THIS_MODULE);
1095 EXPORT_SYMBOL(request_firmware_into_buf);
1098 * request_partial_firmware_into_buf() - load partial firmware into a previously allocated buffer
1099 * @firmware_p: pointer to firmware image
1100 * @name: name of firmware file
1101 * @device: device for which firmware is being loaded and DMA region allocated
1102 * @buf: address of buffer to load firmware into
1103 * @size: size of buffer
1104 * @offset: offset into file to read
1106 * This function works pretty much like request_firmware_into_buf except
1107 * it allows a partial read of the file.
1110 request_partial_firmware_into_buf(const struct firmware **firmware_p,
1111 const char *name, struct device *device,
1112 void *buf, size_t size, size_t offset)
1116 if (fw_cache_is_setup(device, name))
1119 __module_get(THIS_MODULE);
1120 ret = _request_firmware(firmware_p, name, device, buf, size, offset,
1121 FW_OPT_UEVENT | FW_OPT_NOCACHE |
1123 module_put(THIS_MODULE);
1126 EXPORT_SYMBOL(request_partial_firmware_into_buf);
1129 * release_firmware() - release the resource associated with a firmware image
1130 * @fw: firmware resource to release
1132 void release_firmware(const struct firmware *fw)
1135 if (!firmware_is_builtin(fw))
1136 firmware_free_data(fw);
1140 EXPORT_SYMBOL(release_firmware);
1143 struct firmware_work {
1144 struct work_struct work;
1145 struct module *module;
1147 struct device *device;
1149 void (*cont)(const struct firmware *fw, void *context);
1153 static void request_firmware_work_func(struct work_struct *work)
1155 struct firmware_work *fw_work;
1156 const struct firmware *fw;
1158 fw_work = container_of(work, struct firmware_work, work);
1160 _request_firmware(&fw, fw_work->name, fw_work->device, NULL, 0, 0,
1161 fw_work->opt_flags);
1162 fw_work->cont(fw, fw_work->context);
1163 put_device(fw_work->device); /* taken in request_firmware_nowait() */
1165 module_put(fw_work->module);
1166 kfree_const(fw_work->name);
1171 * request_firmware_nowait() - asynchronous version of request_firmware
1172 * @module: module requesting the firmware
1173 * @uevent: sends uevent to copy the firmware image if this flag
1174 * is non-zero else the firmware copy must be done manually.
1175 * @name: name of firmware file
1176 * @device: device for which firmware is being loaded
1177 * @gfp: allocation flags
1178 * @context: will be passed over to @cont, and
1179 * @fw may be %NULL if firmware request fails.
1180 * @cont: function will be called asynchronously when the firmware
1183 * Caller must hold the reference count of @device.
1185 * Asynchronous variant of request_firmware() for user contexts:
1186 * - sleep for as small periods as possible since it may
1187 * increase kernel boot time of built-in device drivers
1188 * requesting firmware in their ->probe() methods, if
1189 * @gfp is GFP_KERNEL.
1191 * - can't sleep at all if @gfp is GFP_ATOMIC.
1194 request_firmware_nowait(
1195 struct module *module, bool uevent,
1196 const char *name, struct device *device, gfp_t gfp, void *context,
1197 void (*cont)(const struct firmware *fw, void *context))
1199 struct firmware_work *fw_work;
1201 fw_work = kzalloc(sizeof(struct firmware_work), gfp);
1205 fw_work->module = module;
1206 fw_work->name = kstrdup_const(name, gfp);
1207 if (!fw_work->name) {
1211 fw_work->device = device;
1212 fw_work->context = context;
1213 fw_work->cont = cont;
1214 fw_work->opt_flags = FW_OPT_NOWAIT |
1215 (uevent ? FW_OPT_UEVENT : FW_OPT_USERHELPER);
1217 if (!uevent && fw_cache_is_setup(device, name)) {
1218 kfree_const(fw_work->name);
1223 if (!try_module_get(module)) {
1224 kfree_const(fw_work->name);
1229 get_device(fw_work->device);
1230 INIT_WORK(&fw_work->work, request_firmware_work_func);
1231 schedule_work(&fw_work->work);
1234 EXPORT_SYMBOL(request_firmware_nowait);
1236 #ifdef CONFIG_FW_CACHE
1237 static ASYNC_DOMAIN_EXCLUSIVE(fw_cache_domain);
1240 * cache_firmware() - cache one firmware image in kernel memory space
1241 * @fw_name: the firmware image name
1243 * Cache firmware in kernel memory so that drivers can use it when
1244 * system isn't ready for them to request firmware image from userspace.
1245 * Once it returns successfully, driver can use request_firmware or its
1246 * nowait version to get the cached firmware without any interacting
1249 * Return 0 if the firmware image has been cached successfully
1250 * Return !0 otherwise
1253 static int cache_firmware(const char *fw_name)
1256 const struct firmware *fw;
1258 pr_debug("%s: %s\n", __func__, fw_name);
1260 ret = request_firmware(&fw, fw_name, NULL);
1264 pr_debug("%s: %s ret=%d\n", __func__, fw_name, ret);
1269 static struct fw_priv *lookup_fw_priv(const char *fw_name)
1271 struct fw_priv *tmp;
1272 struct firmware_cache *fwc = &fw_cache;
1274 spin_lock(&fwc->lock);
1275 tmp = __lookup_fw_priv(fw_name);
1276 spin_unlock(&fwc->lock);
1282 * uncache_firmware() - remove one cached firmware image
1283 * @fw_name: the firmware image name
1285 * Uncache one firmware image which has been cached successfully
1288 * Return 0 if the firmware cache has been removed successfully
1289 * Return !0 otherwise
1292 static int uncache_firmware(const char *fw_name)
1294 struct fw_priv *fw_priv;
1297 pr_debug("%s: %s\n", __func__, fw_name);
1299 if (firmware_request_builtin(&fw, fw_name))
1302 fw_priv = lookup_fw_priv(fw_name);
1304 free_fw_priv(fw_priv);
1311 static struct fw_cache_entry *alloc_fw_cache_entry(const char *name)
1313 struct fw_cache_entry *fce;
1315 fce = kzalloc(sizeof(*fce), GFP_ATOMIC);
1319 fce->name = kstrdup_const(name, GFP_ATOMIC);
1329 static int __fw_entry_found(const char *name)
1331 struct firmware_cache *fwc = &fw_cache;
1332 struct fw_cache_entry *fce;
1334 list_for_each_entry(fce, &fwc->fw_names, list) {
1335 if (!strcmp(fce->name, name))
1341 static void fw_cache_piggyback_on_request(struct fw_priv *fw_priv)
1343 const char *name = fw_priv->fw_name;
1344 struct firmware_cache *fwc = fw_priv->fwc;
1345 struct fw_cache_entry *fce;
1347 spin_lock(&fwc->name_lock);
1348 if (__fw_entry_found(name))
1351 fce = alloc_fw_cache_entry(name);
1353 list_add(&fce->list, &fwc->fw_names);
1354 kref_get(&fw_priv->ref);
1355 pr_debug("%s: fw: %s\n", __func__, name);
1358 spin_unlock(&fwc->name_lock);
1361 static void free_fw_cache_entry(struct fw_cache_entry *fce)
1363 kfree_const(fce->name);
1367 static void __async_dev_cache_fw_image(void *fw_entry,
1368 async_cookie_t cookie)
1370 struct fw_cache_entry *fce = fw_entry;
1371 struct firmware_cache *fwc = &fw_cache;
1374 ret = cache_firmware(fce->name);
1376 spin_lock(&fwc->name_lock);
1377 list_del(&fce->list);
1378 spin_unlock(&fwc->name_lock);
1380 free_fw_cache_entry(fce);
1384 /* called with dev->devres_lock held */
1385 static void dev_create_fw_entry(struct device *dev, void *res,
1388 struct fw_name_devm *fwn = res;
1389 const char *fw_name = fwn->name;
1390 struct list_head *head = data;
1391 struct fw_cache_entry *fce;
1393 fce = alloc_fw_cache_entry(fw_name);
1395 list_add(&fce->list, head);
1398 static int devm_name_match(struct device *dev, void *res,
1401 struct fw_name_devm *fwn = res;
1402 return (fwn->magic == (unsigned long)match_data);
1405 static void dev_cache_fw_image(struct device *dev, void *data)
1408 struct fw_cache_entry *fce;
1409 struct fw_cache_entry *fce_next;
1410 struct firmware_cache *fwc = &fw_cache;
1412 devres_for_each_res(dev, fw_name_devm_release,
1413 devm_name_match, &fw_cache,
1414 dev_create_fw_entry, &todo);
1416 list_for_each_entry_safe(fce, fce_next, &todo, list) {
1417 list_del(&fce->list);
1419 spin_lock(&fwc->name_lock);
1420 /* only one cache entry for one firmware */
1421 if (!__fw_entry_found(fce->name)) {
1422 list_add(&fce->list, &fwc->fw_names);
1424 free_fw_cache_entry(fce);
1427 spin_unlock(&fwc->name_lock);
1430 async_schedule_domain(__async_dev_cache_fw_image,
1436 static void __device_uncache_fw_images(void)
1438 struct firmware_cache *fwc = &fw_cache;
1439 struct fw_cache_entry *fce;
1441 spin_lock(&fwc->name_lock);
1442 while (!list_empty(&fwc->fw_names)) {
1443 fce = list_entry(fwc->fw_names.next,
1444 struct fw_cache_entry, list);
1445 list_del(&fce->list);
1446 spin_unlock(&fwc->name_lock);
1448 uncache_firmware(fce->name);
1449 free_fw_cache_entry(fce);
1451 spin_lock(&fwc->name_lock);
1453 spin_unlock(&fwc->name_lock);
1457 * device_cache_fw_images() - cache devices' firmware
1459 * If one device called request_firmware or its nowait version
1460 * successfully before, the firmware names are recored into the
1461 * device's devres link list, so device_cache_fw_images can call
1462 * cache_firmware() to cache these firmwares for the device,
1463 * then the device driver can load its firmwares easily at
1464 * time when system is not ready to complete loading firmware.
1466 static void device_cache_fw_images(void)
1468 struct firmware_cache *fwc = &fw_cache;
1471 pr_debug("%s\n", __func__);
1473 /* cancel uncache work */
1474 cancel_delayed_work_sync(&fwc->work);
1476 fw_fallback_set_cache_timeout();
1478 mutex_lock(&fw_lock);
1479 fwc->state = FW_LOADER_START_CACHE;
1480 dpm_for_each_dev(NULL, dev_cache_fw_image);
1481 mutex_unlock(&fw_lock);
1483 /* wait for completion of caching firmware for all devices */
1484 async_synchronize_full_domain(&fw_cache_domain);
1486 fw_fallback_set_default_timeout();
1490 * device_uncache_fw_images() - uncache devices' firmware
1492 * uncache all firmwares which have been cached successfully
1493 * by device_uncache_fw_images earlier
1495 static void device_uncache_fw_images(void)
1497 pr_debug("%s\n", __func__);
1498 __device_uncache_fw_images();
1501 static void device_uncache_fw_images_work(struct work_struct *work)
1503 device_uncache_fw_images();
1507 * device_uncache_fw_images_delay() - uncache devices firmwares
1508 * @delay: number of milliseconds to delay uncache device firmwares
1510 * uncache all devices's firmwares which has been cached successfully
1511 * by device_cache_fw_images after @delay milliseconds.
1513 static void device_uncache_fw_images_delay(unsigned long delay)
1515 queue_delayed_work(system_power_efficient_wq, &fw_cache.work,
1516 msecs_to_jiffies(delay));
1519 static int fw_pm_notify(struct notifier_block *notify_block,
1520 unsigned long mode, void *unused)
1523 case PM_HIBERNATION_PREPARE:
1524 case PM_SUSPEND_PREPARE:
1525 case PM_RESTORE_PREPARE:
1527 * kill pending fallback requests with a custom fallback
1528 * to avoid stalling suspend.
1530 kill_pending_fw_fallback_reqs(true);
1531 device_cache_fw_images();
1534 case PM_POST_SUSPEND:
1535 case PM_POST_HIBERNATION:
1536 case PM_POST_RESTORE:
1538 * In case that system sleep failed and syscore_suspend is
1541 mutex_lock(&fw_lock);
1542 fw_cache.state = FW_LOADER_NO_CACHE;
1543 mutex_unlock(&fw_lock);
1545 device_uncache_fw_images_delay(10 * MSEC_PER_SEC);
1552 /* stop caching firmware once syscore_suspend is reached */
1553 static int fw_suspend(void)
1555 fw_cache.state = FW_LOADER_NO_CACHE;
1559 static struct syscore_ops fw_syscore_ops = {
1560 .suspend = fw_suspend,
1563 static int __init register_fw_pm_ops(void)
1567 spin_lock_init(&fw_cache.name_lock);
1568 INIT_LIST_HEAD(&fw_cache.fw_names);
1570 INIT_DELAYED_WORK(&fw_cache.work,
1571 device_uncache_fw_images_work);
1573 fw_cache.pm_notify.notifier_call = fw_pm_notify;
1574 ret = register_pm_notifier(&fw_cache.pm_notify);
1578 register_syscore_ops(&fw_syscore_ops);
1583 static inline void unregister_fw_pm_ops(void)
1585 unregister_syscore_ops(&fw_syscore_ops);
1586 unregister_pm_notifier(&fw_cache.pm_notify);
1589 static void fw_cache_piggyback_on_request(struct fw_priv *fw_priv)
1592 static inline int register_fw_pm_ops(void)
1596 static inline void unregister_fw_pm_ops(void)
1601 static void __init fw_cache_init(void)
1603 spin_lock_init(&fw_cache.lock);
1604 INIT_LIST_HEAD(&fw_cache.head);
1605 fw_cache.state = FW_LOADER_NO_CACHE;
1608 static int fw_shutdown_notify(struct notifier_block *unused1,
1609 unsigned long unused2, void *unused3)
1612 * Kill all pending fallback requests to avoid both stalling shutdown,
1613 * and avoid a deadlock with the usermode_lock.
1615 kill_pending_fw_fallback_reqs(false);
1620 static struct notifier_block fw_shutdown_nb = {
1621 .notifier_call = fw_shutdown_notify,
1624 static int __init firmware_class_init(void)
1628 /* No need to unfold these on exit */
1631 ret = register_fw_pm_ops();
1635 ret = register_reboot_notifier(&fw_shutdown_nb);
1639 return register_sysfs_loader();
1642 unregister_fw_pm_ops();
1646 static void __exit firmware_class_exit(void)
1648 unregister_fw_pm_ops();
1649 unregister_reboot_notifier(&fw_shutdown_nb);
1650 unregister_sysfs_loader();
1653 fs_initcall(firmware_class_init);
1654 module_exit(firmware_class_exit);